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1/*
2 * NSA Security-Enhanced Linux (SELinux) security module
3 *
4 * This file contains the SELinux hook function implementations.
5 *
6 * Authors: Stephen Smalley, <sds@tycho.nsa.gov>
7 * Chris Vance, <cvance@nai.com>
8 * Wayne Salamon, <wsalamon@nai.com>
9 * James Morris <jmorris@redhat.com>
10 *
11 * Copyright (C) 2001,2002 Networks Associates Technology, Inc.
12 * Copyright (C) 2003-2008 Red Hat, Inc., James Morris <jmorris@redhat.com>
13 * Eric Paris <eparis@redhat.com>
14 * Copyright (C) 2004-2005 Trusted Computer Solutions, Inc.
15 * <dgoeddel@trustedcs.com>
16 * Copyright (C) 2006, 2007, 2009 Hewlett-Packard Development Company, L.P.
17 * Paul Moore <paul@paul-moore.com>
18 * Copyright (C) 2007 Hitachi Software Engineering Co., Ltd.
19 * Yuichi Nakamura <ynakam@hitachisoft.jp>
20 * Copyright (C) 2016 Mellanox Technologies
21 *
22 * This program is free software; you can redistribute it and/or modify
23 * it under the terms of the GNU General Public License version 2,
24 * as published by the Free Software Foundation.
25 */
26
27#include <linux/init.h>
28#include <linux/kd.h>
29#include <linux/kernel.h>
30#include <linux/tracehook.h>
31#include <linux/errno.h>
32#include <linux/sched/signal.h>
33#include <linux/sched/task.h>
34#include <linux/lsm_hooks.h>
35#include <linux/xattr.h>
36#include <linux/capability.h>
37#include <linux/unistd.h>
38#include <linux/mm.h>
39#include <linux/mman.h>
40#include <linux/slab.h>
41#include <linux/pagemap.h>
42#include <linux/proc_fs.h>
43#include <linux/swap.h>
44#include <linux/spinlock.h>
45#include <linux/syscalls.h>
46#include <linux/dcache.h>
47#include <linux/file.h>
48#include <linux/fdtable.h>
49#include <linux/namei.h>
50#include <linux/mount.h>
51#include <linux/netfilter_ipv4.h>
52#include <linux/netfilter_ipv6.h>
53#include <linux/tty.h>
54#include <net/icmp.h>
55#include <net/ip.h> /* for local_port_range[] */
56#include <net/tcp.h> /* struct or_callable used in sock_rcv_skb */
57#include <net/inet_connection_sock.h>
58#include <net/net_namespace.h>
59#include <net/netlabel.h>
60#include <linux/uaccess.h>
61#include <asm/ioctls.h>
62#include <linux/atomic.h>
63#include <linux/bitops.h>
64#include <linux/interrupt.h>
65#include <linux/netdevice.h> /* for network interface checks */
66#include <net/netlink.h>
67#include <linux/tcp.h>
68#include <linux/udp.h>
69#include <linux/dccp.h>
70#include <linux/sctp.h>
71#include <net/sctp/structs.h>
72#include <linux/quota.h>
73#include <linux/un.h> /* for Unix socket types */
74#include <net/af_unix.h> /* for Unix socket types */
75#include <linux/parser.h>
76#include <linux/nfs_mount.h>
77#include <net/ipv6.h>
78#include <linux/hugetlb.h>
79#include <linux/personality.h>
80#include <linux/audit.h>
81#include <linux/string.h>
82#include <linux/selinux.h>
83#include <linux/mutex.h>
84#include <linux/posix-timers.h>
85#include <linux/syslog.h>
86#include <linux/user_namespace.h>
87#include <linux/export.h>
88#include <linux/msg.h>
89#include <linux/shm.h>
90#include <linux/bpf.h>
91
92#include "avc.h"
93#include "objsec.h"
94#include "netif.h"
95#include "netnode.h"
96#include "netport.h"
97#include "ibpkey.h"
98#include "xfrm.h"
99#include "netlabel.h"
100#include "audit.h"
101#include "avc_ss.h"
102
103struct selinux_state selinux_state;
104
105/* SECMARK reference count */
106static atomic_t selinux_secmark_refcount = ATOMIC_INIT(0);
107
108#ifdef CONFIG_SECURITY_SELINUX_DEVELOP
109static int selinux_enforcing_boot;
110
111static int __init enforcing_setup(char *str)
112{
113 unsigned long enforcing;
114 if (!kstrtoul(str, 0, &enforcing))
115 selinux_enforcing_boot = enforcing ? 1 : 0;
116 return 1;
117}
118__setup("enforcing=", enforcing_setup);
119#else
120#define selinux_enforcing_boot 1
121#endif
122
123#ifdef CONFIG_SECURITY_SELINUX_BOOTPARAM
124int selinux_enabled = CONFIG_SECURITY_SELINUX_BOOTPARAM_VALUE;
125
126static int __init selinux_enabled_setup(char *str)
127{
128 unsigned long enabled;
129 if (!kstrtoul(str, 0, &enabled))
130 selinux_enabled = enabled ? 1 : 0;
131 return 1;
132}
133__setup("selinux=", selinux_enabled_setup);
134#else
135int selinux_enabled = 1;
136#endif
137
138static unsigned int selinux_checkreqprot_boot =
139 CONFIG_SECURITY_SELINUX_CHECKREQPROT_VALUE;
140
141static int __init checkreqprot_setup(char *str)
142{
143 unsigned long checkreqprot;
144
145 if (!kstrtoul(str, 0, &checkreqprot))
146 selinux_checkreqprot_boot = checkreqprot ? 1 : 0;
147 return 1;
148}
149__setup("checkreqprot=", checkreqprot_setup);
150
151static struct kmem_cache *sel_inode_cache;
152static struct kmem_cache *file_security_cache;
153
154/**
155 * selinux_secmark_enabled - Check to see if SECMARK is currently enabled
156 *
157 * Description:
158 * This function checks the SECMARK reference counter to see if any SECMARK
159 * targets are currently configured, if the reference counter is greater than
160 * zero SECMARK is considered to be enabled. Returns true (1) if SECMARK is
161 * enabled, false (0) if SECMARK is disabled. If the always_check_network
162 * policy capability is enabled, SECMARK is always considered enabled.
163 *
164 */
165static int selinux_secmark_enabled(void)
166{
167 return (selinux_policycap_alwaysnetwork() ||
168 atomic_read(&selinux_secmark_refcount));
169}
170
171/**
172 * selinux_peerlbl_enabled - Check to see if peer labeling is currently enabled
173 *
174 * Description:
175 * This function checks if NetLabel or labeled IPSEC is enabled. Returns true
176 * (1) if any are enabled or false (0) if neither are enabled. If the
177 * always_check_network policy capability is enabled, peer labeling
178 * is always considered enabled.
179 *
180 */
181static int selinux_peerlbl_enabled(void)
182{
183 return (selinux_policycap_alwaysnetwork() ||
184 netlbl_enabled() || selinux_xfrm_enabled());
185}
186
187static int selinux_netcache_avc_callback(u32 event)
188{
189 if (event == AVC_CALLBACK_RESET) {
190 sel_netif_flush();
191 sel_netnode_flush();
192 sel_netport_flush();
193 synchronize_net();
194 }
195 return 0;
196}
197
198static int selinux_lsm_notifier_avc_callback(u32 event)
199{
200 if (event == AVC_CALLBACK_RESET) {
201 sel_ib_pkey_flush();
202 call_lsm_notifier(LSM_POLICY_CHANGE, NULL);
203 }
204
205 return 0;
206}
207
208/*
209 * initialise the security for the init task
210 */
211static void cred_init_security(void)
212{
213 struct cred *cred = (struct cred *) current->real_cred;
214 struct task_security_struct *tsec;
215
216 tsec = kzalloc(sizeof(struct task_security_struct), GFP_KERNEL);
217 if (!tsec)
218 panic("SELinux: Failed to initialize initial task.\n");
219
220 tsec->osid = tsec->sid = SECINITSID_KERNEL;
221 cred->security = tsec;
222}
223
224/*
225 * get the security ID of a set of credentials
226 */
227static inline u32 cred_sid(const struct cred *cred)
228{
229 const struct task_security_struct *tsec;
230
231 tsec = cred->security;
232 return tsec->sid;
233}
234
235/*
236 * get the objective security ID of a task
237 */
238static inline u32 task_sid(const struct task_struct *task)
239{
240 u32 sid;
241
242 rcu_read_lock();
243 sid = cred_sid(__task_cred(task));
244 rcu_read_unlock();
245 return sid;
246}
247
248/* Allocate and free functions for each kind of security blob. */
249
250static int inode_alloc_security(struct inode *inode)
251{
252 struct inode_security_struct *isec;
253 u32 sid = current_sid();
254
255 isec = kmem_cache_zalloc(sel_inode_cache, GFP_NOFS);
256 if (!isec)
257 return -ENOMEM;
258
259 spin_lock_init(&isec->lock);
260 INIT_LIST_HEAD(&isec->list);
261 isec->inode = inode;
262 isec->sid = SECINITSID_UNLABELED;
263 isec->sclass = SECCLASS_FILE;
264 isec->task_sid = sid;
265 isec->initialized = LABEL_INVALID;
266 inode->i_security = isec;
267
268 return 0;
269}
270
271static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dentry);
272
273/*
274 * Try reloading inode security labels that have been marked as invalid. The
275 * @may_sleep parameter indicates when sleeping and thus reloading labels is
276 * allowed; when set to false, returns -ECHILD when the label is
277 * invalid. The @opt_dentry parameter should be set to a dentry of the inode;
278 * when no dentry is available, set it to NULL instead.
279 */
280static int __inode_security_revalidate(struct inode *inode,
281 struct dentry *opt_dentry,
282 bool may_sleep)
283{
284 struct inode_security_struct *isec = inode->i_security;
285
286 might_sleep_if(may_sleep);
287
288 if (selinux_state.initialized &&
289 isec->initialized != LABEL_INITIALIZED) {
290 if (!may_sleep)
291 return -ECHILD;
292
293 /*
294 * Try reloading the inode security label. This will fail if
295 * @opt_dentry is NULL and no dentry for this inode can be
296 * found; in that case, continue using the old label.
297 */
298 inode_doinit_with_dentry(inode, opt_dentry);
299 }
300 return 0;
301}
302
303static struct inode_security_struct *inode_security_novalidate(struct inode *inode)
304{
305 return inode->i_security;
306}
307
308static struct inode_security_struct *inode_security_rcu(struct inode *inode, bool rcu)
309{
310 int error;
311
312 error = __inode_security_revalidate(inode, NULL, !rcu);
313 if (error)
314 return ERR_PTR(error);
315 return inode->i_security;
316}
317
318/*
319 * Get the security label of an inode.
320 */
321static struct inode_security_struct *inode_security(struct inode *inode)
322{
323 __inode_security_revalidate(inode, NULL, true);
324 return inode->i_security;
325}
326
327static struct inode_security_struct *backing_inode_security_novalidate(struct dentry *dentry)
328{
329 struct inode *inode = d_backing_inode(dentry);
330
331 return inode->i_security;
332}
333
334/*
335 * Get the security label of a dentry's backing inode.
336 */
337static struct inode_security_struct *backing_inode_security(struct dentry *dentry)
338{
339 struct inode *inode = d_backing_inode(dentry);
340
341 __inode_security_revalidate(inode, dentry, true);
342 return inode->i_security;
343}
344
345static void inode_free_rcu(struct rcu_head *head)
346{
347 struct inode_security_struct *isec;
348
349 isec = container_of(head, struct inode_security_struct, rcu);
350 kmem_cache_free(sel_inode_cache, isec);
351}
352
353static void inode_free_security(struct inode *inode)
354{
355 struct inode_security_struct *isec = inode->i_security;
356 struct superblock_security_struct *sbsec = inode->i_sb->s_security;
357
358 /*
359 * As not all inode security structures are in a list, we check for
360 * empty list outside of the lock to make sure that we won't waste
361 * time taking a lock doing nothing.
362 *
363 * The list_del_init() function can be safely called more than once.
364 * It should not be possible for this function to be called with
365 * concurrent list_add(), but for better safety against future changes
366 * in the code, we use list_empty_careful() here.
367 */
368 if (!list_empty_careful(&isec->list)) {
369 spin_lock(&sbsec->isec_lock);
370 list_del_init(&isec->list);
371 spin_unlock(&sbsec->isec_lock);
372 }
373
374 /*
375 * The inode may still be referenced in a path walk and
376 * a call to selinux_inode_permission() can be made
377 * after inode_free_security() is called. Ideally, the VFS
378 * wouldn't do this, but fixing that is a much harder
379 * job. For now, simply free the i_security via RCU, and
380 * leave the current inode->i_security pointer intact.
381 * The inode will be freed after the RCU grace period too.
382 */
383 call_rcu(&isec->rcu, inode_free_rcu);
384}
385
386static int file_alloc_security(struct file *file)
387{
388 struct file_security_struct *fsec;
389 u32 sid = current_sid();
390
391 fsec = kmem_cache_zalloc(file_security_cache, GFP_KERNEL);
392 if (!fsec)
393 return -ENOMEM;
394
395 fsec->sid = sid;
396 fsec->fown_sid = sid;
397 file->f_security = fsec;
398
399 return 0;
400}
401
402static void file_free_security(struct file *file)
403{
404 struct file_security_struct *fsec = file->f_security;
405 file->f_security = NULL;
406 kmem_cache_free(file_security_cache, fsec);
407}
408
409static int superblock_alloc_security(struct super_block *sb)
410{
411 struct superblock_security_struct *sbsec;
412
413 sbsec = kzalloc(sizeof(struct superblock_security_struct), GFP_KERNEL);
414 if (!sbsec)
415 return -ENOMEM;
416
417 mutex_init(&sbsec->lock);
418 INIT_LIST_HEAD(&sbsec->isec_head);
419 spin_lock_init(&sbsec->isec_lock);
420 sbsec->sb = sb;
421 sbsec->sid = SECINITSID_UNLABELED;
422 sbsec->def_sid = SECINITSID_FILE;
423 sbsec->mntpoint_sid = SECINITSID_UNLABELED;
424 sb->s_security = sbsec;
425
426 return 0;
427}
428
429static void superblock_free_security(struct super_block *sb)
430{
431 struct superblock_security_struct *sbsec = sb->s_security;
432 sb->s_security = NULL;
433 kfree(sbsec);
434}
435
436static inline int inode_doinit(struct inode *inode)
437{
438 return inode_doinit_with_dentry(inode, NULL);
439}
440
441enum {
442 Opt_error = -1,
443 Opt_context = 1,
444 Opt_fscontext = 2,
445 Opt_defcontext = 3,
446 Opt_rootcontext = 4,
447 Opt_labelsupport = 5,
448 Opt_nextmntopt = 6,
449};
450
451#define NUM_SEL_MNT_OPTS (Opt_nextmntopt - 1)
452
453static const match_table_t tokens = {
454 {Opt_context, CONTEXT_STR "%s"},
455 {Opt_fscontext, FSCONTEXT_STR "%s"},
456 {Opt_defcontext, DEFCONTEXT_STR "%s"},
457 {Opt_rootcontext, ROOTCONTEXT_STR "%s"},
458 {Opt_labelsupport, LABELSUPP_STR},
459 {Opt_error, NULL},
460};
461
462#define SEL_MOUNT_FAIL_MSG "SELinux: duplicate or incompatible mount options\n"
463
464static int may_context_mount_sb_relabel(u32 sid,
465 struct superblock_security_struct *sbsec,
466 const struct cred *cred)
467{
468 const struct task_security_struct *tsec = cred->security;
469 int rc;
470
471 rc = avc_has_perm(&selinux_state,
472 tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM,
473 FILESYSTEM__RELABELFROM, NULL);
474 if (rc)
475 return rc;
476
477 rc = avc_has_perm(&selinux_state,
478 tsec->sid, sid, SECCLASS_FILESYSTEM,
479 FILESYSTEM__RELABELTO, NULL);
480 return rc;
481}
482
483static int may_context_mount_inode_relabel(u32 sid,
484 struct superblock_security_struct *sbsec,
485 const struct cred *cred)
486{
487 const struct task_security_struct *tsec = cred->security;
488 int rc;
489 rc = avc_has_perm(&selinux_state,
490 tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM,
491 FILESYSTEM__RELABELFROM, NULL);
492 if (rc)
493 return rc;
494
495 rc = avc_has_perm(&selinux_state,
496 sid, sbsec->sid, SECCLASS_FILESYSTEM,
497 FILESYSTEM__ASSOCIATE, NULL);
498 return rc;
499}
500
501static int selinux_is_sblabel_mnt(struct super_block *sb)
502{
503 struct superblock_security_struct *sbsec = sb->s_security;
504
505 return sbsec->behavior == SECURITY_FS_USE_XATTR ||
506 sbsec->behavior == SECURITY_FS_USE_TRANS ||
507 sbsec->behavior == SECURITY_FS_USE_TASK ||
508 sbsec->behavior == SECURITY_FS_USE_NATIVE ||
509 /* Special handling. Genfs but also in-core setxattr handler */
510 !strcmp(sb->s_type->name, "sysfs") ||
511 !strcmp(sb->s_type->name, "pstore") ||
512 !strcmp(sb->s_type->name, "debugfs") ||
513 !strcmp(sb->s_type->name, "tracefs") ||
514 !strcmp(sb->s_type->name, "rootfs") ||
515 (selinux_policycap_cgroupseclabel() &&
516 (!strcmp(sb->s_type->name, "cgroup") ||
517 !strcmp(sb->s_type->name, "cgroup2")));
518}
519
520static int sb_finish_set_opts(struct super_block *sb)
521{
522 struct superblock_security_struct *sbsec = sb->s_security;
523 struct dentry *root = sb->s_root;
524 struct inode *root_inode = d_backing_inode(root);
525 int rc = 0;
526
527 if (sbsec->behavior == SECURITY_FS_USE_XATTR) {
528 /* Make sure that the xattr handler exists and that no
529 error other than -ENODATA is returned by getxattr on
530 the root directory. -ENODATA is ok, as this may be
531 the first boot of the SELinux kernel before we have
532 assigned xattr values to the filesystem. */
533 if (!(root_inode->i_opflags & IOP_XATTR)) {
534 printk(KERN_WARNING "SELinux: (dev %s, type %s) has no "
535 "xattr support\n", sb->s_id, sb->s_type->name);
536 rc = -EOPNOTSUPP;
537 goto out;
538 }
539
540 rc = __vfs_getxattr(root, root_inode, XATTR_NAME_SELINUX, NULL, 0);
541 if (rc < 0 && rc != -ENODATA) {
542 if (rc == -EOPNOTSUPP)
543 printk(KERN_WARNING "SELinux: (dev %s, type "
544 "%s) has no security xattr handler\n",
545 sb->s_id, sb->s_type->name);
546 else
547 printk(KERN_WARNING "SELinux: (dev %s, type "
548 "%s) getxattr errno %d\n", sb->s_id,
549 sb->s_type->name, -rc);
550 goto out;
551 }
552 }
553
554 sbsec->flags |= SE_SBINITIALIZED;
555
556 /*
557 * Explicitly set or clear SBLABEL_MNT. It's not sufficient to simply
558 * leave the flag untouched because sb_clone_mnt_opts might be handing
559 * us a superblock that needs the flag to be cleared.
560 */
561 if (selinux_is_sblabel_mnt(sb))
562 sbsec->flags |= SBLABEL_MNT;
563 else
564 sbsec->flags &= ~SBLABEL_MNT;
565
566 /* Initialize the root inode. */
567 rc = inode_doinit_with_dentry(root_inode, root);
568
569 /* Initialize any other inodes associated with the superblock, e.g.
570 inodes created prior to initial policy load or inodes created
571 during get_sb by a pseudo filesystem that directly
572 populates itself. */
573 spin_lock(&sbsec->isec_lock);
574next_inode:
575 if (!list_empty(&sbsec->isec_head)) {
576 struct inode_security_struct *isec =
577 list_entry(sbsec->isec_head.next,
578 struct inode_security_struct, list);
579 struct inode *inode = isec->inode;
580 list_del_init(&isec->list);
581 spin_unlock(&sbsec->isec_lock);
582 inode = igrab(inode);
583 if (inode) {
584 if (!IS_PRIVATE(inode))
585 inode_doinit(inode);
586 iput(inode);
587 }
588 spin_lock(&sbsec->isec_lock);
589 goto next_inode;
590 }
591 spin_unlock(&sbsec->isec_lock);
592out:
593 return rc;
594}
595
596/*
597 * This function should allow an FS to ask what it's mount security
598 * options were so it can use those later for submounts, displaying
599 * mount options, or whatever.
600 */
601static int selinux_get_mnt_opts(const struct super_block *sb,
602 struct security_mnt_opts *opts)
603{
604 int rc = 0, i;
605 struct superblock_security_struct *sbsec = sb->s_security;
606 char *context = NULL;
607 u32 len;
608 char tmp;
609
610 security_init_mnt_opts(opts);
611
612 if (!(sbsec->flags & SE_SBINITIALIZED))
613 return -EINVAL;
614
615 if (!selinux_state.initialized)
616 return -EINVAL;
617
618 /* make sure we always check enough bits to cover the mask */
619 BUILD_BUG_ON(SE_MNTMASK >= (1 << NUM_SEL_MNT_OPTS));
620
621 tmp = sbsec->flags & SE_MNTMASK;
622 /* count the number of mount options for this sb */
623 for (i = 0; i < NUM_SEL_MNT_OPTS; i++) {
624 if (tmp & 0x01)
625 opts->num_mnt_opts++;
626 tmp >>= 1;
627 }
628 /* Check if the Label support flag is set */
629 if (sbsec->flags & SBLABEL_MNT)
630 opts->num_mnt_opts++;
631
632 opts->mnt_opts = kcalloc(opts->num_mnt_opts, sizeof(char *), GFP_ATOMIC);
633 if (!opts->mnt_opts) {
634 rc = -ENOMEM;
635 goto out_free;
636 }
637
638 opts->mnt_opts_flags = kcalloc(opts->num_mnt_opts, sizeof(int), GFP_ATOMIC);
639 if (!opts->mnt_opts_flags) {
640 rc = -ENOMEM;
641 goto out_free;
642 }
643
644 i = 0;
645 if (sbsec->flags & FSCONTEXT_MNT) {
646 rc = security_sid_to_context(&selinux_state, sbsec->sid,
647 &context, &len);
648 if (rc)
649 goto out_free;
650 opts->mnt_opts[i] = context;
651 opts->mnt_opts_flags[i++] = FSCONTEXT_MNT;
652 }
653 if (sbsec->flags & CONTEXT_MNT) {
654 rc = security_sid_to_context(&selinux_state,
655 sbsec->mntpoint_sid,
656 &context, &len);
657 if (rc)
658 goto out_free;
659 opts->mnt_opts[i] = context;
660 opts->mnt_opts_flags[i++] = CONTEXT_MNT;
661 }
662 if (sbsec->flags & DEFCONTEXT_MNT) {
663 rc = security_sid_to_context(&selinux_state, sbsec->def_sid,
664 &context, &len);
665 if (rc)
666 goto out_free;
667 opts->mnt_opts[i] = context;
668 opts->mnt_opts_flags[i++] = DEFCONTEXT_MNT;
669 }
670 if (sbsec->flags & ROOTCONTEXT_MNT) {
671 struct dentry *root = sbsec->sb->s_root;
672 struct inode_security_struct *isec = backing_inode_security(root);
673
674 rc = security_sid_to_context(&selinux_state, isec->sid,
675 &context, &len);
676 if (rc)
677 goto out_free;
678 opts->mnt_opts[i] = context;
679 opts->mnt_opts_flags[i++] = ROOTCONTEXT_MNT;
680 }
681 if (sbsec->flags & SBLABEL_MNT) {
682 opts->mnt_opts[i] = NULL;
683 opts->mnt_opts_flags[i++] = SBLABEL_MNT;
684 }
685
686 BUG_ON(i != opts->num_mnt_opts);
687
688 return 0;
689
690out_free:
691 security_free_mnt_opts(opts);
692 return rc;
693}
694
695static int bad_option(struct superblock_security_struct *sbsec, char flag,
696 u32 old_sid, u32 new_sid)
697{
698 char mnt_flags = sbsec->flags & SE_MNTMASK;
699
700 /* check if the old mount command had the same options */
701 if (sbsec->flags & SE_SBINITIALIZED)
702 if (!(sbsec->flags & flag) ||
703 (old_sid != new_sid))
704 return 1;
705
706 /* check if we were passed the same options twice,
707 * aka someone passed context=a,context=b
708 */
709 if (!(sbsec->flags & SE_SBINITIALIZED))
710 if (mnt_flags & flag)
711 return 1;
712 return 0;
713}
714
715/*
716 * Allow filesystems with binary mount data to explicitly set mount point
717 * labeling information.
718 */
719static int selinux_set_mnt_opts(struct super_block *sb,
720 struct security_mnt_opts *opts,
721 unsigned long kern_flags,
722 unsigned long *set_kern_flags)
723{
724 const struct cred *cred = current_cred();
725 int rc = 0, i;
726 struct superblock_security_struct *sbsec = sb->s_security;
727 const char *name = sb->s_type->name;
728 struct dentry *root = sbsec->sb->s_root;
729 struct inode_security_struct *root_isec;
730 u32 fscontext_sid = 0, context_sid = 0, rootcontext_sid = 0;
731 u32 defcontext_sid = 0;
732 char **mount_options = opts->mnt_opts;
733 int *flags = opts->mnt_opts_flags;
734 int num_opts = opts->num_mnt_opts;
735
736 mutex_lock(&sbsec->lock);
737
738 if (!selinux_state.initialized) {
739 if (!num_opts) {
740 /* Defer initialization until selinux_complete_init,
741 after the initial policy is loaded and the security
742 server is ready to handle calls. */
743 goto out;
744 }
745 rc = -EINVAL;
746 printk(KERN_WARNING "SELinux: Unable to set superblock options "
747 "before the security server is initialized\n");
748 goto out;
749 }
750 if (kern_flags && !set_kern_flags) {
751 /* Specifying internal flags without providing a place to
752 * place the results is not allowed */
753 rc = -EINVAL;
754 goto out;
755 }
756
757 /*
758 * Binary mount data FS will come through this function twice. Once
759 * from an explicit call and once from the generic calls from the vfs.
760 * Since the generic VFS calls will not contain any security mount data
761 * we need to skip the double mount verification.
762 *
763 * This does open a hole in which we will not notice if the first
764 * mount using this sb set explict options and a second mount using
765 * this sb does not set any security options. (The first options
766 * will be used for both mounts)
767 */
768 if ((sbsec->flags & SE_SBINITIALIZED) && (sb->s_type->fs_flags & FS_BINARY_MOUNTDATA)
769 && (num_opts == 0))
770 goto out;
771
772 root_isec = backing_inode_security_novalidate(root);
773
774 /*
775 * parse the mount options, check if they are valid sids.
776 * also check if someone is trying to mount the same sb more
777 * than once with different security options.
778 */
779 for (i = 0; i < num_opts; i++) {
780 u32 sid;
781
782 if (flags[i] == SBLABEL_MNT)
783 continue;
784 rc = security_context_str_to_sid(&selinux_state,
785 mount_options[i], &sid,
786 GFP_KERNEL);
787 if (rc) {
788 printk(KERN_WARNING "SELinux: security_context_str_to_sid"
789 "(%s) failed for (dev %s, type %s) errno=%d\n",
790 mount_options[i], sb->s_id, name, rc);
791 goto out;
792 }
793 switch (flags[i]) {
794 case FSCONTEXT_MNT:
795 fscontext_sid = sid;
796
797 if (bad_option(sbsec, FSCONTEXT_MNT, sbsec->sid,
798 fscontext_sid))
799 goto out_double_mount;
800
801 sbsec->flags |= FSCONTEXT_MNT;
802 break;
803 case CONTEXT_MNT:
804 context_sid = sid;
805
806 if (bad_option(sbsec, CONTEXT_MNT, sbsec->mntpoint_sid,
807 context_sid))
808 goto out_double_mount;
809
810 sbsec->flags |= CONTEXT_MNT;
811 break;
812 case ROOTCONTEXT_MNT:
813 rootcontext_sid = sid;
814
815 if (bad_option(sbsec, ROOTCONTEXT_MNT, root_isec->sid,
816 rootcontext_sid))
817 goto out_double_mount;
818
819 sbsec->flags |= ROOTCONTEXT_MNT;
820
821 break;
822 case DEFCONTEXT_MNT:
823 defcontext_sid = sid;
824
825 if (bad_option(sbsec, DEFCONTEXT_MNT, sbsec->def_sid,
826 defcontext_sid))
827 goto out_double_mount;
828
829 sbsec->flags |= DEFCONTEXT_MNT;
830
831 break;
832 default:
833 rc = -EINVAL;
834 goto out;
835 }
836 }
837
838 if (sbsec->flags & SE_SBINITIALIZED) {
839 /* previously mounted with options, but not on this attempt? */
840 if ((sbsec->flags & SE_MNTMASK) && !num_opts)
841 goto out_double_mount;
842 rc = 0;
843 goto out;
844 }
845
846 if (strcmp(sb->s_type->name, "proc") == 0)
847 sbsec->flags |= SE_SBPROC | SE_SBGENFS;
848
849 if (!strcmp(sb->s_type->name, "debugfs") ||
850 !strcmp(sb->s_type->name, "tracefs") ||
851 !strcmp(sb->s_type->name, "sysfs") ||
852 !strcmp(sb->s_type->name, "pstore") ||
853 !strcmp(sb->s_type->name, "cgroup") ||
854 !strcmp(sb->s_type->name, "cgroup2"))
855 sbsec->flags |= SE_SBGENFS;
856
857 if (!sbsec->behavior) {
858 /*
859 * Determine the labeling behavior to use for this
860 * filesystem type.
861 */
862 rc = security_fs_use(&selinux_state, sb);
863 if (rc) {
864 printk(KERN_WARNING
865 "%s: security_fs_use(%s) returned %d\n",
866 __func__, sb->s_type->name, rc);
867 goto out;
868 }
869 }
870
871 /*
872 * If this is a user namespace mount and the filesystem type is not
873 * explicitly whitelisted, then no contexts are allowed on the command
874 * line and security labels must be ignored.
875 */
876 if (sb->s_user_ns != &init_user_ns &&
877 strcmp(sb->s_type->name, "tmpfs") &&
878 strcmp(sb->s_type->name, "ramfs") &&
879 strcmp(sb->s_type->name, "devpts")) {
880 if (context_sid || fscontext_sid || rootcontext_sid ||
881 defcontext_sid) {
882 rc = -EACCES;
883 goto out;
884 }
885 if (sbsec->behavior == SECURITY_FS_USE_XATTR) {
886 sbsec->behavior = SECURITY_FS_USE_MNTPOINT;
887 rc = security_transition_sid(&selinux_state,
888 current_sid(),
889 current_sid(),
890 SECCLASS_FILE, NULL,
891 &sbsec->mntpoint_sid);
892 if (rc)
893 goto out;
894 }
895 goto out_set_opts;
896 }
897
898 /* sets the context of the superblock for the fs being mounted. */
899 if (fscontext_sid) {
900 rc = may_context_mount_sb_relabel(fscontext_sid, sbsec, cred);
901 if (rc)
902 goto out;
903
904 sbsec->sid = fscontext_sid;
905 }
906
907 /*
908 * Switch to using mount point labeling behavior.
909 * sets the label used on all file below the mountpoint, and will set
910 * the superblock context if not already set.
911 */
912 if (kern_flags & SECURITY_LSM_NATIVE_LABELS && !context_sid) {
913 sbsec->behavior = SECURITY_FS_USE_NATIVE;
914 *set_kern_flags |= SECURITY_LSM_NATIVE_LABELS;
915 }
916
917 if (context_sid) {
918 if (!fscontext_sid) {
919 rc = may_context_mount_sb_relabel(context_sid, sbsec,
920 cred);
921 if (rc)
922 goto out;
923 sbsec->sid = context_sid;
924 } else {
925 rc = may_context_mount_inode_relabel(context_sid, sbsec,
926 cred);
927 if (rc)
928 goto out;
929 }
930 if (!rootcontext_sid)
931 rootcontext_sid = context_sid;
932
933 sbsec->mntpoint_sid = context_sid;
934 sbsec->behavior = SECURITY_FS_USE_MNTPOINT;
935 }
936
937 if (rootcontext_sid) {
938 rc = may_context_mount_inode_relabel(rootcontext_sid, sbsec,
939 cred);
940 if (rc)
941 goto out;
942
943 root_isec->sid = rootcontext_sid;
944 root_isec->initialized = LABEL_INITIALIZED;
945 }
946
947 if (defcontext_sid) {
948 if (sbsec->behavior != SECURITY_FS_USE_XATTR &&
949 sbsec->behavior != SECURITY_FS_USE_NATIVE) {
950 rc = -EINVAL;
951 printk(KERN_WARNING "SELinux: defcontext option is "
952 "invalid for this filesystem type\n");
953 goto out;
954 }
955
956 if (defcontext_sid != sbsec->def_sid) {
957 rc = may_context_mount_inode_relabel(defcontext_sid,
958 sbsec, cred);
959 if (rc)
960 goto out;
961 }
962
963 sbsec->def_sid = defcontext_sid;
964 }
965
966out_set_opts:
967 rc = sb_finish_set_opts(sb);
968out:
969 mutex_unlock(&sbsec->lock);
970 return rc;
971out_double_mount:
972 rc = -EINVAL;
973 printk(KERN_WARNING "SELinux: mount invalid. Same superblock, different "
974 "security settings for (dev %s, type %s)\n", sb->s_id, name);
975 goto out;
976}
977
978static int selinux_cmp_sb_context(const struct super_block *oldsb,
979 const struct super_block *newsb)
980{
981 struct superblock_security_struct *old = oldsb->s_security;
982 struct superblock_security_struct *new = newsb->s_security;
983 char oldflags = old->flags & SE_MNTMASK;
984 char newflags = new->flags & SE_MNTMASK;
985
986 if (oldflags != newflags)
987 goto mismatch;
988 if ((oldflags & FSCONTEXT_MNT) && old->sid != new->sid)
989 goto mismatch;
990 if ((oldflags & CONTEXT_MNT) && old->mntpoint_sid != new->mntpoint_sid)
991 goto mismatch;
992 if ((oldflags & DEFCONTEXT_MNT) && old->def_sid != new->def_sid)
993 goto mismatch;
994 if (oldflags & ROOTCONTEXT_MNT) {
995 struct inode_security_struct *oldroot = backing_inode_security(oldsb->s_root);
996 struct inode_security_struct *newroot = backing_inode_security(newsb->s_root);
997 if (oldroot->sid != newroot->sid)
998 goto mismatch;
999 }
1000 return 0;
1001mismatch:
1002 printk(KERN_WARNING "SELinux: mount invalid. Same superblock, "
1003 "different security settings for (dev %s, "
1004 "type %s)\n", newsb->s_id, newsb->s_type->name);
1005 return -EBUSY;
1006}
1007
1008static int selinux_sb_clone_mnt_opts(const struct super_block *oldsb,
1009 struct super_block *newsb,
1010 unsigned long kern_flags,
1011 unsigned long *set_kern_flags)
1012{
1013 int rc = 0;
1014 const struct superblock_security_struct *oldsbsec = oldsb->s_security;
1015 struct superblock_security_struct *newsbsec = newsb->s_security;
1016
1017 int set_fscontext = (oldsbsec->flags & FSCONTEXT_MNT);
1018 int set_context = (oldsbsec->flags & CONTEXT_MNT);
1019 int set_rootcontext = (oldsbsec->flags & ROOTCONTEXT_MNT);
1020
1021 /*
1022 * if the parent was able to be mounted it clearly had no special lsm
1023 * mount options. thus we can safely deal with this superblock later
1024 */
1025 if (!selinux_state.initialized)
1026 return 0;
1027
1028 /*
1029 * Specifying internal flags without providing a place to
1030 * place the results is not allowed.
1031 */
1032 if (kern_flags && !set_kern_flags)
1033 return -EINVAL;
1034
1035 /* how can we clone if the old one wasn't set up?? */
1036 BUG_ON(!(oldsbsec->flags & SE_SBINITIALIZED));
1037
1038 /* if fs is reusing a sb, make sure that the contexts match */
1039 if (newsbsec->flags & SE_SBINITIALIZED)
1040 return selinux_cmp_sb_context(oldsb, newsb);
1041
1042 mutex_lock(&newsbsec->lock);
1043
1044 newsbsec->flags = oldsbsec->flags;
1045
1046 newsbsec->sid = oldsbsec->sid;
1047 newsbsec->def_sid = oldsbsec->def_sid;
1048 newsbsec->behavior = oldsbsec->behavior;
1049
1050 if (newsbsec->behavior == SECURITY_FS_USE_NATIVE &&
1051 !(kern_flags & SECURITY_LSM_NATIVE_LABELS) && !set_context) {
1052 rc = security_fs_use(&selinux_state, newsb);
1053 if (rc)
1054 goto out;
1055 }
1056
1057 if (kern_flags & SECURITY_LSM_NATIVE_LABELS && !set_context) {
1058 newsbsec->behavior = SECURITY_FS_USE_NATIVE;
1059 *set_kern_flags |= SECURITY_LSM_NATIVE_LABELS;
1060 }
1061
1062 if (set_context) {
1063 u32 sid = oldsbsec->mntpoint_sid;
1064
1065 if (!set_fscontext)
1066 newsbsec->sid = sid;
1067 if (!set_rootcontext) {
1068 struct inode_security_struct *newisec = backing_inode_security(newsb->s_root);
1069 newisec->sid = sid;
1070 }
1071 newsbsec->mntpoint_sid = sid;
1072 }
1073 if (set_rootcontext) {
1074 const struct inode_security_struct *oldisec = backing_inode_security(oldsb->s_root);
1075 struct inode_security_struct *newisec = backing_inode_security(newsb->s_root);
1076
1077 newisec->sid = oldisec->sid;
1078 }
1079
1080 sb_finish_set_opts(newsb);
1081out:
1082 mutex_unlock(&newsbsec->lock);
1083 return rc;
1084}
1085
1086static int selinux_parse_opts_str(char *options,
1087 struct security_mnt_opts *opts)
1088{
1089 char *p;
1090 char *context = NULL, *defcontext = NULL;
1091 char *fscontext = NULL, *rootcontext = NULL;
1092 int rc, num_mnt_opts = 0;
1093
1094 opts->num_mnt_opts = 0;
1095
1096 /* Standard string-based options. */
1097 while ((p = strsep(&options, "|")) != NULL) {
1098 int token;
1099 substring_t args[MAX_OPT_ARGS];
1100
1101 if (!*p)
1102 continue;
1103
1104 token = match_token(p, tokens, args);
1105
1106 switch (token) {
1107 case Opt_context:
1108 if (context || defcontext) {
1109 rc = -EINVAL;
1110 printk(KERN_WARNING SEL_MOUNT_FAIL_MSG);
1111 goto out_err;
1112 }
1113 context = match_strdup(&args[0]);
1114 if (!context) {
1115 rc = -ENOMEM;
1116 goto out_err;
1117 }
1118 break;
1119
1120 case Opt_fscontext:
1121 if (fscontext) {
1122 rc = -EINVAL;
1123 printk(KERN_WARNING SEL_MOUNT_FAIL_MSG);
1124 goto out_err;
1125 }
1126 fscontext = match_strdup(&args[0]);
1127 if (!fscontext) {
1128 rc = -ENOMEM;
1129 goto out_err;
1130 }
1131 break;
1132
1133 case Opt_rootcontext:
1134 if (rootcontext) {
1135 rc = -EINVAL;
1136 printk(KERN_WARNING SEL_MOUNT_FAIL_MSG);
1137 goto out_err;
1138 }
1139 rootcontext = match_strdup(&args[0]);
1140 if (!rootcontext) {
1141 rc = -ENOMEM;
1142 goto out_err;
1143 }
1144 break;
1145
1146 case Opt_defcontext:
1147 if (context || defcontext) {
1148 rc = -EINVAL;
1149 printk(KERN_WARNING SEL_MOUNT_FAIL_MSG);
1150 goto out_err;
1151 }
1152 defcontext = match_strdup(&args[0]);
1153 if (!defcontext) {
1154 rc = -ENOMEM;
1155 goto out_err;
1156 }
1157 break;
1158 case Opt_labelsupport:
1159 break;
1160 default:
1161 rc = -EINVAL;
1162 printk(KERN_WARNING "SELinux: unknown mount option\n");
1163 goto out_err;
1164
1165 }
1166 }
1167
1168 rc = -ENOMEM;
1169 opts->mnt_opts = kcalloc(NUM_SEL_MNT_OPTS, sizeof(char *), GFP_KERNEL);
1170 if (!opts->mnt_opts)
1171 goto out_err;
1172
1173 opts->mnt_opts_flags = kcalloc(NUM_SEL_MNT_OPTS, sizeof(int),
1174 GFP_KERNEL);
1175 if (!opts->mnt_opts_flags)
1176 goto out_err;
1177
1178 if (fscontext) {
1179 opts->mnt_opts[num_mnt_opts] = fscontext;
1180 opts->mnt_opts_flags[num_mnt_opts++] = FSCONTEXT_MNT;
1181 }
1182 if (context) {
1183 opts->mnt_opts[num_mnt_opts] = context;
1184 opts->mnt_opts_flags[num_mnt_opts++] = CONTEXT_MNT;
1185 }
1186 if (rootcontext) {
1187 opts->mnt_opts[num_mnt_opts] = rootcontext;
1188 opts->mnt_opts_flags[num_mnt_opts++] = ROOTCONTEXT_MNT;
1189 }
1190 if (defcontext) {
1191 opts->mnt_opts[num_mnt_opts] = defcontext;
1192 opts->mnt_opts_flags[num_mnt_opts++] = DEFCONTEXT_MNT;
1193 }
1194
1195 opts->num_mnt_opts = num_mnt_opts;
1196 return 0;
1197
1198out_err:
1199 security_free_mnt_opts(opts);
1200 kfree(context);
1201 kfree(defcontext);
1202 kfree(fscontext);
1203 kfree(rootcontext);
1204 return rc;
1205}
1206/*
1207 * string mount options parsing and call set the sbsec
1208 */
1209static int superblock_doinit(struct super_block *sb, void *data)
1210{
1211 int rc = 0;
1212 char *options = data;
1213 struct security_mnt_opts opts;
1214
1215 security_init_mnt_opts(&opts);
1216
1217 if (!data)
1218 goto out;
1219
1220 BUG_ON(sb->s_type->fs_flags & FS_BINARY_MOUNTDATA);
1221
1222 rc = selinux_parse_opts_str(options, &opts);
1223 if (rc)
1224 goto out_err;
1225
1226out:
1227 rc = selinux_set_mnt_opts(sb, &opts, 0, NULL);
1228
1229out_err:
1230 security_free_mnt_opts(&opts);
1231 return rc;
1232}
1233
1234static void selinux_write_opts(struct seq_file *m,
1235 struct security_mnt_opts *opts)
1236{
1237 int i;
1238 char *prefix;
1239
1240 for (i = 0; i < opts->num_mnt_opts; i++) {
1241 char *has_comma;
1242
1243 if (opts->mnt_opts[i])
1244 has_comma = strchr(opts->mnt_opts[i], ',');
1245 else
1246 has_comma = NULL;
1247
1248 switch (opts->mnt_opts_flags[i]) {
1249 case CONTEXT_MNT:
1250 prefix = CONTEXT_STR;
1251 break;
1252 case FSCONTEXT_MNT:
1253 prefix = FSCONTEXT_STR;
1254 break;
1255 case ROOTCONTEXT_MNT:
1256 prefix = ROOTCONTEXT_STR;
1257 break;
1258 case DEFCONTEXT_MNT:
1259 prefix = DEFCONTEXT_STR;
1260 break;
1261 case SBLABEL_MNT:
1262 seq_putc(m, ',');
1263 seq_puts(m, LABELSUPP_STR);
1264 continue;
1265 default:
1266 BUG();
1267 return;
1268 };
1269 /* we need a comma before each option */
1270 seq_putc(m, ',');
1271 seq_puts(m, prefix);
1272 if (has_comma)
1273 seq_putc(m, '\"');
1274 seq_escape(m, opts->mnt_opts[i], "\"\n\\");
1275 if (has_comma)
1276 seq_putc(m, '\"');
1277 }
1278}
1279
1280static int selinux_sb_show_options(struct seq_file *m, struct super_block *sb)
1281{
1282 struct security_mnt_opts opts;
1283 int rc;
1284
1285 rc = selinux_get_mnt_opts(sb, &opts);
1286 if (rc) {
1287 /* before policy load we may get EINVAL, don't show anything */
1288 if (rc == -EINVAL)
1289 rc = 0;
1290 return rc;
1291 }
1292
1293 selinux_write_opts(m, &opts);
1294
1295 security_free_mnt_opts(&opts);
1296
1297 return rc;
1298}
1299
1300static inline u16 inode_mode_to_security_class(umode_t mode)
1301{
1302 switch (mode & S_IFMT) {
1303 case S_IFSOCK:
1304 return SECCLASS_SOCK_FILE;
1305 case S_IFLNK:
1306 return SECCLASS_LNK_FILE;
1307 case S_IFREG:
1308 return SECCLASS_FILE;
1309 case S_IFBLK:
1310 return SECCLASS_BLK_FILE;
1311 case S_IFDIR:
1312 return SECCLASS_DIR;
1313 case S_IFCHR:
1314 return SECCLASS_CHR_FILE;
1315 case S_IFIFO:
1316 return SECCLASS_FIFO_FILE;
1317
1318 }
1319
1320 return SECCLASS_FILE;
1321}
1322
1323static inline int default_protocol_stream(int protocol)
1324{
1325 return (protocol == IPPROTO_IP || protocol == IPPROTO_TCP);
1326}
1327
1328static inline int default_protocol_dgram(int protocol)
1329{
1330 return (protocol == IPPROTO_IP || protocol == IPPROTO_UDP);
1331}
1332
1333static inline u16 socket_type_to_security_class(int family, int type, int protocol)
1334{
1335 int extsockclass = selinux_policycap_extsockclass();
1336
1337 switch (family) {
1338 case PF_UNIX:
1339 switch (type) {
1340 case SOCK_STREAM:
1341 case SOCK_SEQPACKET:
1342 return SECCLASS_UNIX_STREAM_SOCKET;
1343 case SOCK_DGRAM:
1344 case SOCK_RAW:
1345 return SECCLASS_UNIX_DGRAM_SOCKET;
1346 }
1347 break;
1348 case PF_INET:
1349 case PF_INET6:
1350 switch (type) {
1351 case SOCK_STREAM:
1352 case SOCK_SEQPACKET:
1353 if (default_protocol_stream(protocol))
1354 return SECCLASS_TCP_SOCKET;
1355 else if (extsockclass && protocol == IPPROTO_SCTP)
1356 return SECCLASS_SCTP_SOCKET;
1357 else
1358 return SECCLASS_RAWIP_SOCKET;
1359 case SOCK_DGRAM:
1360 if (default_protocol_dgram(protocol))
1361 return SECCLASS_UDP_SOCKET;
1362 else if (extsockclass && (protocol == IPPROTO_ICMP ||
1363 protocol == IPPROTO_ICMPV6))
1364 return SECCLASS_ICMP_SOCKET;
1365 else
1366 return SECCLASS_RAWIP_SOCKET;
1367 case SOCK_DCCP:
1368 return SECCLASS_DCCP_SOCKET;
1369 default:
1370 return SECCLASS_RAWIP_SOCKET;
1371 }
1372 break;
1373 case PF_NETLINK:
1374 switch (protocol) {
1375 case NETLINK_ROUTE:
1376 return SECCLASS_NETLINK_ROUTE_SOCKET;
1377 case NETLINK_SOCK_DIAG:
1378 return SECCLASS_NETLINK_TCPDIAG_SOCKET;
1379 case NETLINK_NFLOG:
1380 return SECCLASS_NETLINK_NFLOG_SOCKET;
1381 case NETLINK_XFRM:
1382 return SECCLASS_NETLINK_XFRM_SOCKET;
1383 case NETLINK_SELINUX:
1384 return SECCLASS_NETLINK_SELINUX_SOCKET;
1385 case NETLINK_ISCSI:
1386 return SECCLASS_NETLINK_ISCSI_SOCKET;
1387 case NETLINK_AUDIT:
1388 return SECCLASS_NETLINK_AUDIT_SOCKET;
1389 case NETLINK_FIB_LOOKUP:
1390 return SECCLASS_NETLINK_FIB_LOOKUP_SOCKET;
1391 case NETLINK_CONNECTOR:
1392 return SECCLASS_NETLINK_CONNECTOR_SOCKET;
1393 case NETLINK_NETFILTER:
1394 return SECCLASS_NETLINK_NETFILTER_SOCKET;
1395 case NETLINK_DNRTMSG:
1396 return SECCLASS_NETLINK_DNRT_SOCKET;
1397 case NETLINK_KOBJECT_UEVENT:
1398 return SECCLASS_NETLINK_KOBJECT_UEVENT_SOCKET;
1399 case NETLINK_GENERIC:
1400 return SECCLASS_NETLINK_GENERIC_SOCKET;
1401 case NETLINK_SCSITRANSPORT:
1402 return SECCLASS_NETLINK_SCSITRANSPORT_SOCKET;
1403 case NETLINK_RDMA:
1404 return SECCLASS_NETLINK_RDMA_SOCKET;
1405 case NETLINK_CRYPTO:
1406 return SECCLASS_NETLINK_CRYPTO_SOCKET;
1407 default:
1408 return SECCLASS_NETLINK_SOCKET;
1409 }
1410 case PF_PACKET:
1411 return SECCLASS_PACKET_SOCKET;
1412 case PF_KEY:
1413 return SECCLASS_KEY_SOCKET;
1414 case PF_APPLETALK:
1415 return SECCLASS_APPLETALK_SOCKET;
1416 }
1417
1418 if (extsockclass) {
1419 switch (family) {
1420 case PF_AX25:
1421 return SECCLASS_AX25_SOCKET;
1422 case PF_IPX:
1423 return SECCLASS_IPX_SOCKET;
1424 case PF_NETROM:
1425 return SECCLASS_NETROM_SOCKET;
1426 case PF_ATMPVC:
1427 return SECCLASS_ATMPVC_SOCKET;
1428 case PF_X25:
1429 return SECCLASS_X25_SOCKET;
1430 case PF_ROSE:
1431 return SECCLASS_ROSE_SOCKET;
1432 case PF_DECnet:
1433 return SECCLASS_DECNET_SOCKET;
1434 case PF_ATMSVC:
1435 return SECCLASS_ATMSVC_SOCKET;
1436 case PF_RDS:
1437 return SECCLASS_RDS_SOCKET;
1438 case PF_IRDA:
1439 return SECCLASS_IRDA_SOCKET;
1440 case PF_PPPOX:
1441 return SECCLASS_PPPOX_SOCKET;
1442 case PF_LLC:
1443 return SECCLASS_LLC_SOCKET;
1444 case PF_CAN:
1445 return SECCLASS_CAN_SOCKET;
1446 case PF_TIPC:
1447 return SECCLASS_TIPC_SOCKET;
1448 case PF_BLUETOOTH:
1449 return SECCLASS_BLUETOOTH_SOCKET;
1450 case PF_IUCV:
1451 return SECCLASS_IUCV_SOCKET;
1452 case PF_RXRPC:
1453 return SECCLASS_RXRPC_SOCKET;
1454 case PF_ISDN:
1455 return SECCLASS_ISDN_SOCKET;
1456 case PF_PHONET:
1457 return SECCLASS_PHONET_SOCKET;
1458 case PF_IEEE802154:
1459 return SECCLASS_IEEE802154_SOCKET;
1460 case PF_CAIF:
1461 return SECCLASS_CAIF_SOCKET;
1462 case PF_ALG:
1463 return SECCLASS_ALG_SOCKET;
1464 case PF_NFC:
1465 return SECCLASS_NFC_SOCKET;
1466 case PF_VSOCK:
1467 return SECCLASS_VSOCK_SOCKET;
1468 case PF_KCM:
1469 return SECCLASS_KCM_SOCKET;
1470 case PF_QIPCRTR:
1471 return SECCLASS_QIPCRTR_SOCKET;
1472 case PF_SMC:
1473 return SECCLASS_SMC_SOCKET;
1474#if PF_MAX > 44
1475#error New address family defined, please update this function.
1476#endif
1477 }
1478 }
1479
1480 return SECCLASS_SOCKET;
1481}
1482
1483static int selinux_genfs_get_sid(struct dentry *dentry,
1484 u16 tclass,
1485 u16 flags,
1486 u32 *sid)
1487{
1488 int rc;
1489 struct super_block *sb = dentry->d_sb;
1490 char *buffer, *path;
1491
1492 buffer = (char *)__get_free_page(GFP_KERNEL);
1493 if (!buffer)
1494 return -ENOMEM;
1495
1496 path = dentry_path_raw(dentry, buffer, PAGE_SIZE);
1497 if (IS_ERR(path))
1498 rc = PTR_ERR(path);
1499 else {
1500 if (flags & SE_SBPROC) {
1501 /* each process gets a /proc/PID/ entry. Strip off the
1502 * PID part to get a valid selinux labeling.
1503 * e.g. /proc/1/net/rpc/nfs -> /net/rpc/nfs */
1504 while (path[1] >= '0' && path[1] <= '9') {
1505 path[1] = '/';
1506 path++;
1507 }
1508 }
1509 rc = security_genfs_sid(&selinux_state, sb->s_type->name,
1510 path, tclass, sid);
1511 }
1512 free_page((unsigned long)buffer);
1513 return rc;
1514}
1515
1516/* The inode's security attributes must be initialized before first use. */
1517static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dentry)
1518{
1519 struct superblock_security_struct *sbsec = NULL;
1520 struct inode_security_struct *isec = inode->i_security;
1521 u32 task_sid, sid = 0;
1522 u16 sclass;
1523 struct dentry *dentry;
1524#define INITCONTEXTLEN 255
1525 char *context = NULL;
1526 unsigned len = 0;
1527 int rc = 0;
1528
1529 if (isec->initialized == LABEL_INITIALIZED)
1530 return 0;
1531
1532 spin_lock(&isec->lock);
1533 if (isec->initialized == LABEL_INITIALIZED)
1534 goto out_unlock;
1535
1536 if (isec->sclass == SECCLASS_FILE)
1537 isec->sclass = inode_mode_to_security_class(inode->i_mode);
1538
1539 sbsec = inode->i_sb->s_security;
1540 if (!(sbsec->flags & SE_SBINITIALIZED)) {
1541 /* Defer initialization until selinux_complete_init,
1542 after the initial policy is loaded and the security
1543 server is ready to handle calls. */
1544 spin_lock(&sbsec->isec_lock);
1545 if (list_empty(&isec->list))
1546 list_add(&isec->list, &sbsec->isec_head);
1547 spin_unlock(&sbsec->isec_lock);
1548 goto out_unlock;
1549 }
1550
1551 sclass = isec->sclass;
1552 task_sid = isec->task_sid;
1553 sid = isec->sid;
1554 isec->initialized = LABEL_PENDING;
1555 spin_unlock(&isec->lock);
1556
1557 switch (sbsec->behavior) {
1558 case SECURITY_FS_USE_NATIVE:
1559 break;
1560 case SECURITY_FS_USE_XATTR:
1561 if (!(inode->i_opflags & IOP_XATTR)) {
1562 sid = sbsec->def_sid;
1563 break;
1564 }
1565 /* Need a dentry, since the xattr API requires one.
1566 Life would be simpler if we could just pass the inode. */
1567 if (opt_dentry) {
1568 /* Called from d_instantiate or d_splice_alias. */
1569 dentry = dget(opt_dentry);
1570 } else {
1571 /*
1572 * Called from selinux_complete_init, try to find a dentry.
1573 * Some filesystems really want a connected one, so try
1574 * that first. We could split SECURITY_FS_USE_XATTR in
1575 * two, depending upon that...
1576 */
1577 dentry = d_find_alias(inode);
1578 if (!dentry)
1579 dentry = d_find_any_alias(inode);
1580 }
1581 if (!dentry) {
1582 /*
1583 * this is can be hit on boot when a file is accessed
1584 * before the policy is loaded. When we load policy we
1585 * may find inodes that have no dentry on the
1586 * sbsec->isec_head list. No reason to complain as these
1587 * will get fixed up the next time we go through
1588 * inode_doinit with a dentry, before these inodes could
1589 * be used again by userspace.
1590 */
1591 goto out;
1592 }
1593
1594 len = INITCONTEXTLEN;
1595 context = kmalloc(len+1, GFP_NOFS);
1596 if (!context) {
1597 rc = -ENOMEM;
1598 dput(dentry);
1599 goto out;
1600 }
1601 context[len] = '\0';
1602 rc = __vfs_getxattr(dentry, inode, XATTR_NAME_SELINUX, context, len);
1603 if (rc == -ERANGE) {
1604 kfree(context);
1605
1606 /* Need a larger buffer. Query for the right size. */
1607 rc = __vfs_getxattr(dentry, inode, XATTR_NAME_SELINUX, NULL, 0);
1608 if (rc < 0) {
1609 dput(dentry);
1610 goto out;
1611 }
1612 len = rc;
1613 context = kmalloc(len+1, GFP_NOFS);
1614 if (!context) {
1615 rc = -ENOMEM;
1616 dput(dentry);
1617 goto out;
1618 }
1619 context[len] = '\0';
1620 rc = __vfs_getxattr(dentry, inode, XATTR_NAME_SELINUX, context, len);
1621 }
1622 dput(dentry);
1623 if (rc < 0) {
1624 if (rc != -ENODATA) {
1625 printk(KERN_WARNING "SELinux: %s: getxattr returned "
1626 "%d for dev=%s ino=%ld\n", __func__,
1627 -rc, inode->i_sb->s_id, inode->i_ino);
1628 kfree(context);
1629 goto out;
1630 }
1631 /* Map ENODATA to the default file SID */
1632 sid = sbsec->def_sid;
1633 rc = 0;
1634 } else {
1635 rc = security_context_to_sid_default(&selinux_state,
1636 context, rc, &sid,
1637 sbsec->def_sid,
1638 GFP_NOFS);
1639 if (rc) {
1640 char *dev = inode->i_sb->s_id;
1641 unsigned long ino = inode->i_ino;
1642
1643 if (rc == -EINVAL) {
1644 if (printk_ratelimit())
1645 printk(KERN_NOTICE "SELinux: inode=%lu on dev=%s was found to have an invalid "
1646 "context=%s. This indicates you may need to relabel the inode or the "
1647 "filesystem in question.\n", ino, dev, context);
1648 } else {
1649 printk(KERN_WARNING "SELinux: %s: context_to_sid(%s) "
1650 "returned %d for dev=%s ino=%ld\n",
1651 __func__, context, -rc, dev, ino);
1652 }
1653 kfree(context);
1654 /* Leave with the unlabeled SID */
1655 rc = 0;
1656 break;
1657 }
1658 }
1659 kfree(context);
1660 break;
1661 case SECURITY_FS_USE_TASK:
1662 sid = task_sid;
1663 break;
1664 case SECURITY_FS_USE_TRANS:
1665 /* Default to the fs SID. */
1666 sid = sbsec->sid;
1667
1668 /* Try to obtain a transition SID. */
1669 rc = security_transition_sid(&selinux_state, task_sid, sid,
1670 sclass, NULL, &sid);
1671 if (rc)
1672 goto out;
1673 break;
1674 case SECURITY_FS_USE_MNTPOINT:
1675 sid = sbsec->mntpoint_sid;
1676 break;
1677 default:
1678 /* Default to the fs superblock SID. */
1679 sid = sbsec->sid;
1680
1681 if ((sbsec->flags & SE_SBGENFS) && !S_ISLNK(inode->i_mode)) {
1682 /* We must have a dentry to determine the label on
1683 * procfs inodes */
1684 if (opt_dentry) {
1685 /* Called from d_instantiate or
1686 * d_splice_alias. */
1687 dentry = dget(opt_dentry);
1688 } else {
1689 /* Called from selinux_complete_init, try to
1690 * find a dentry. Some filesystems really want
1691 * a connected one, so try that first.
1692 */
1693 dentry = d_find_alias(inode);
1694 if (!dentry)
1695 dentry = d_find_any_alias(inode);
1696 }
1697 /*
1698 * This can be hit on boot when a file is accessed
1699 * before the policy is loaded. When we load policy we
1700 * may find inodes that have no dentry on the
1701 * sbsec->isec_head list. No reason to complain as
1702 * these will get fixed up the next time we go through
1703 * inode_doinit() with a dentry, before these inodes
1704 * could be used again by userspace.
1705 */
1706 if (!dentry)
1707 goto out;
1708 rc = selinux_genfs_get_sid(dentry, sclass,
1709 sbsec->flags, &sid);
1710 dput(dentry);
1711 if (rc)
1712 goto out;
1713 }
1714 break;
1715 }
1716
1717out:
1718 spin_lock(&isec->lock);
1719 if (isec->initialized == LABEL_PENDING) {
1720 if (!sid || rc) {
1721 isec->initialized = LABEL_INVALID;
1722 goto out_unlock;
1723 }
1724
1725 isec->initialized = LABEL_INITIALIZED;
1726 isec->sid = sid;
1727 }
1728
1729out_unlock:
1730 spin_unlock(&isec->lock);
1731 return rc;
1732}
1733
1734/* Convert a Linux signal to an access vector. */
1735static inline u32 signal_to_av(int sig)
1736{
1737 u32 perm = 0;
1738
1739 switch (sig) {
1740 case SIGCHLD:
1741 /* Commonly granted from child to parent. */
1742 perm = PROCESS__SIGCHLD;
1743 break;
1744 case SIGKILL:
1745 /* Cannot be caught or ignored */
1746 perm = PROCESS__SIGKILL;
1747 break;
1748 case SIGSTOP:
1749 /* Cannot be caught or ignored */
1750 perm = PROCESS__SIGSTOP;
1751 break;
1752 default:
1753 /* All other signals. */
1754 perm = PROCESS__SIGNAL;
1755 break;
1756 }
1757
1758 return perm;
1759}
1760
1761#if CAP_LAST_CAP > 63
1762#error Fix SELinux to handle capabilities > 63.
1763#endif
1764
1765/* Check whether a task is allowed to use a capability. */
1766static int cred_has_capability(const struct cred *cred,
1767 int cap, int audit, bool initns)
1768{
1769 struct common_audit_data ad;
1770 struct av_decision avd;
1771 u16 sclass;
1772 u32 sid = cred_sid(cred);
1773 u32 av = CAP_TO_MASK(cap);
1774 int rc;
1775
1776 ad.type = LSM_AUDIT_DATA_CAP;
1777 ad.u.cap = cap;
1778
1779 switch (CAP_TO_INDEX(cap)) {
1780 case 0:
1781 sclass = initns ? SECCLASS_CAPABILITY : SECCLASS_CAP_USERNS;
1782 break;
1783 case 1:
1784 sclass = initns ? SECCLASS_CAPABILITY2 : SECCLASS_CAP2_USERNS;
1785 break;
1786 default:
1787 printk(KERN_ERR
1788 "SELinux: out of range capability %d\n", cap);
1789 BUG();
1790 return -EINVAL;
1791 }
1792
1793 rc = avc_has_perm_noaudit(&selinux_state,
1794 sid, sid, sclass, av, 0, &avd);
1795 if (audit == SECURITY_CAP_AUDIT) {
1796 int rc2 = avc_audit(&selinux_state,
1797 sid, sid, sclass, av, &avd, rc, &ad, 0);
1798 if (rc2)
1799 return rc2;
1800 }
1801 return rc;
1802}
1803
1804/* Check whether a task has a particular permission to an inode.
1805 The 'adp' parameter is optional and allows other audit
1806 data to be passed (e.g. the dentry). */
1807static int inode_has_perm(const struct cred *cred,
1808 struct inode *inode,
1809 u32 perms,
1810 struct common_audit_data *adp)
1811{
1812 struct inode_security_struct *isec;
1813 u32 sid;
1814
1815 validate_creds(cred);
1816
1817 if (unlikely(IS_PRIVATE(inode)))
1818 return 0;
1819
1820 sid = cred_sid(cred);
1821 isec = inode->i_security;
1822
1823 return avc_has_perm(&selinux_state,
1824 sid, isec->sid, isec->sclass, perms, adp);
1825}
1826
1827/* Same as inode_has_perm, but pass explicit audit data containing
1828 the dentry to help the auditing code to more easily generate the
1829 pathname if needed. */
1830static inline int dentry_has_perm(const struct cred *cred,
1831 struct dentry *dentry,
1832 u32 av)
1833{
1834 struct inode *inode = d_backing_inode(dentry);
1835 struct common_audit_data ad;
1836
1837 ad.type = LSM_AUDIT_DATA_DENTRY;
1838 ad.u.dentry = dentry;
1839 __inode_security_revalidate(inode, dentry, true);
1840 return inode_has_perm(cred, inode, av, &ad);
1841}
1842
1843/* Same as inode_has_perm, but pass explicit audit data containing
1844 the path to help the auditing code to more easily generate the
1845 pathname if needed. */
1846static inline int path_has_perm(const struct cred *cred,
1847 const struct path *path,
1848 u32 av)
1849{
1850 struct inode *inode = d_backing_inode(path->dentry);
1851 struct common_audit_data ad;
1852
1853 ad.type = LSM_AUDIT_DATA_PATH;
1854 ad.u.path = *path;
1855 __inode_security_revalidate(inode, path->dentry, true);
1856 return inode_has_perm(cred, inode, av, &ad);
1857}
1858
1859/* Same as path_has_perm, but uses the inode from the file struct. */
1860static inline int file_path_has_perm(const struct cred *cred,
1861 struct file *file,
1862 u32 av)
1863{
1864 struct common_audit_data ad;
1865
1866 ad.type = LSM_AUDIT_DATA_FILE;
1867 ad.u.file = file;
1868 return inode_has_perm(cred, file_inode(file), av, &ad);
1869}
1870
1871#ifdef CONFIG_BPF_SYSCALL
1872static int bpf_fd_pass(struct file *file, u32 sid);
1873#endif
1874
1875/* Check whether a task can use an open file descriptor to
1876 access an inode in a given way. Check access to the
1877 descriptor itself, and then use dentry_has_perm to
1878 check a particular permission to the file.
1879 Access to the descriptor is implicitly granted if it
1880 has the same SID as the process. If av is zero, then
1881 access to the file is not checked, e.g. for cases
1882 where only the descriptor is affected like seek. */
1883static int file_has_perm(const struct cred *cred,
1884 struct file *file,
1885 u32 av)
1886{
1887 struct file_security_struct *fsec = file->f_security;
1888 struct inode *inode = file_inode(file);
1889 struct common_audit_data ad;
1890 u32 sid = cred_sid(cred);
1891 int rc;
1892
1893 ad.type = LSM_AUDIT_DATA_FILE;
1894 ad.u.file = file;
1895
1896 if (sid != fsec->sid) {
1897 rc = avc_has_perm(&selinux_state,
1898 sid, fsec->sid,
1899 SECCLASS_FD,
1900 FD__USE,
1901 &ad);
1902 if (rc)
1903 goto out;
1904 }
1905
1906#ifdef CONFIG_BPF_SYSCALL
1907 rc = bpf_fd_pass(file, cred_sid(cred));
1908 if (rc)
1909 return rc;
1910#endif
1911
1912 /* av is zero if only checking access to the descriptor. */
1913 rc = 0;
1914 if (av)
1915 rc = inode_has_perm(cred, inode, av, &ad);
1916
1917out:
1918 return rc;
1919}
1920
1921/*
1922 * Determine the label for an inode that might be unioned.
1923 */
1924static int
1925selinux_determine_inode_label(const struct task_security_struct *tsec,
1926 struct inode *dir,
1927 const struct qstr *name, u16 tclass,
1928 u32 *_new_isid)
1929{
1930 const struct superblock_security_struct *sbsec = dir->i_sb->s_security;
1931
1932 if ((sbsec->flags & SE_SBINITIALIZED) &&
1933 (sbsec->behavior == SECURITY_FS_USE_MNTPOINT)) {
1934 *_new_isid = sbsec->mntpoint_sid;
1935 } else if ((sbsec->flags & SBLABEL_MNT) &&
1936 tsec->create_sid) {
1937 *_new_isid = tsec->create_sid;
1938 } else {
1939 const struct inode_security_struct *dsec = inode_security(dir);
1940 return security_transition_sid(&selinux_state, tsec->sid,
1941 dsec->sid, tclass,
1942 name, _new_isid);
1943 }
1944
1945 return 0;
1946}
1947
1948/* Check whether a task can create a file. */
1949static int may_create(struct inode *dir,
1950 struct dentry *dentry,
1951 u16 tclass)
1952{
1953 const struct task_security_struct *tsec = current_security();
1954 struct inode_security_struct *dsec;
1955 struct superblock_security_struct *sbsec;
1956 u32 sid, newsid;
1957 struct common_audit_data ad;
1958 int rc;
1959
1960 dsec = inode_security(dir);
1961 sbsec = dir->i_sb->s_security;
1962
1963 sid = tsec->sid;
1964
1965 ad.type = LSM_AUDIT_DATA_DENTRY;
1966 ad.u.dentry = dentry;
1967
1968 rc = avc_has_perm(&selinux_state,
1969 sid, dsec->sid, SECCLASS_DIR,
1970 DIR__ADD_NAME | DIR__SEARCH,
1971 &ad);
1972 if (rc)
1973 return rc;
1974
1975 rc = selinux_determine_inode_label(current_security(), dir,
1976 &dentry->d_name, tclass, &newsid);
1977 if (rc)
1978 return rc;
1979
1980 rc = avc_has_perm(&selinux_state,
1981 sid, newsid, tclass, FILE__CREATE, &ad);
1982 if (rc)
1983 return rc;
1984
1985 return avc_has_perm(&selinux_state,
1986 newsid, sbsec->sid,
1987 SECCLASS_FILESYSTEM,
1988 FILESYSTEM__ASSOCIATE, &ad);
1989}
1990
1991#define MAY_LINK 0
1992#define MAY_UNLINK 1
1993#define MAY_RMDIR 2
1994
1995/* Check whether a task can link, unlink, or rmdir a file/directory. */
1996static int may_link(struct inode *dir,
1997 struct dentry *dentry,
1998 int kind)
1999
2000{
2001 struct inode_security_struct *dsec, *isec;
2002 struct common_audit_data ad;
2003 u32 sid = current_sid();
2004 u32 av;
2005 int rc;
2006
2007 dsec = inode_security(dir);
2008 isec = backing_inode_security(dentry);
2009
2010 ad.type = LSM_AUDIT_DATA_DENTRY;
2011 ad.u.dentry = dentry;
2012
2013 av = DIR__SEARCH;
2014 av |= (kind ? DIR__REMOVE_NAME : DIR__ADD_NAME);
2015 rc = avc_has_perm(&selinux_state,
2016 sid, dsec->sid, SECCLASS_DIR, av, &ad);
2017 if (rc)
2018 return rc;
2019
2020 switch (kind) {
2021 case MAY_LINK:
2022 av = FILE__LINK;
2023 break;
2024 case MAY_UNLINK:
2025 av = FILE__UNLINK;
2026 break;
2027 case MAY_RMDIR:
2028 av = DIR__RMDIR;
2029 break;
2030 default:
2031 printk(KERN_WARNING "SELinux: %s: unrecognized kind %d\n",
2032 __func__, kind);
2033 return 0;
2034 }
2035
2036 rc = avc_has_perm(&selinux_state,
2037 sid, isec->sid, isec->sclass, av, &ad);
2038 return rc;
2039}
2040
2041static inline int may_rename(struct inode *old_dir,
2042 struct dentry *old_dentry,
2043 struct inode *new_dir,
2044 struct dentry *new_dentry)
2045{
2046 struct inode_security_struct *old_dsec, *new_dsec, *old_isec, *new_isec;
2047 struct common_audit_data ad;
2048 u32 sid = current_sid();
2049 u32 av;
2050 int old_is_dir, new_is_dir;
2051 int rc;
2052
2053 old_dsec = inode_security(old_dir);
2054 old_isec = backing_inode_security(old_dentry);
2055 old_is_dir = d_is_dir(old_dentry);
2056 new_dsec = inode_security(new_dir);
2057
2058 ad.type = LSM_AUDIT_DATA_DENTRY;
2059
2060 ad.u.dentry = old_dentry;
2061 rc = avc_has_perm(&selinux_state,
2062 sid, old_dsec->sid, SECCLASS_DIR,
2063 DIR__REMOVE_NAME | DIR__SEARCH, &ad);
2064 if (rc)
2065 return rc;
2066 rc = avc_has_perm(&selinux_state,
2067 sid, old_isec->sid,
2068 old_isec->sclass, FILE__RENAME, &ad);
2069 if (rc)
2070 return rc;
2071 if (old_is_dir && new_dir != old_dir) {
2072 rc = avc_has_perm(&selinux_state,
2073 sid, old_isec->sid,
2074 old_isec->sclass, DIR__REPARENT, &ad);
2075 if (rc)
2076 return rc;
2077 }
2078
2079 ad.u.dentry = new_dentry;
2080 av = DIR__ADD_NAME | DIR__SEARCH;
2081 if (d_is_positive(new_dentry))
2082 av |= DIR__REMOVE_NAME;
2083 rc = avc_has_perm(&selinux_state,
2084 sid, new_dsec->sid, SECCLASS_DIR, av, &ad);
2085 if (rc)
2086 return rc;
2087 if (d_is_positive(new_dentry)) {
2088 new_isec = backing_inode_security(new_dentry);
2089 new_is_dir = d_is_dir(new_dentry);
2090 rc = avc_has_perm(&selinux_state,
2091 sid, new_isec->sid,
2092 new_isec->sclass,
2093 (new_is_dir ? DIR__RMDIR : FILE__UNLINK), &ad);
2094 if (rc)
2095 return rc;
2096 }
2097
2098 return 0;
2099}
2100
2101/* Check whether a task can perform a filesystem operation. */
2102static int superblock_has_perm(const struct cred *cred,
2103 struct super_block *sb,
2104 u32 perms,
2105 struct common_audit_data *ad)
2106{
2107 struct superblock_security_struct *sbsec;
2108 u32 sid = cred_sid(cred);
2109
2110 sbsec = sb->s_security;
2111 return avc_has_perm(&selinux_state,
2112 sid, sbsec->sid, SECCLASS_FILESYSTEM, perms, ad);
2113}
2114
2115/* Convert a Linux mode and permission mask to an access vector. */
2116static inline u32 file_mask_to_av(int mode, int mask)
2117{
2118 u32 av = 0;
2119
2120 if (!S_ISDIR(mode)) {
2121 if (mask & MAY_EXEC)
2122 av |= FILE__EXECUTE;
2123 if (mask & MAY_READ)
2124 av |= FILE__READ;
2125
2126 if (mask & MAY_APPEND)
2127 av |= FILE__APPEND;
2128 else if (mask & MAY_WRITE)
2129 av |= FILE__WRITE;
2130
2131 } else {
2132 if (mask & MAY_EXEC)
2133 av |= DIR__SEARCH;
2134 if (mask & MAY_WRITE)
2135 av |= DIR__WRITE;
2136 if (mask & MAY_READ)
2137 av |= DIR__READ;
2138 }
2139
2140 return av;
2141}
2142
2143/* Convert a Linux file to an access vector. */
2144static inline u32 file_to_av(struct file *file)
2145{
2146 u32 av = 0;
2147
2148 if (file->f_mode & FMODE_READ)
2149 av |= FILE__READ;
2150 if (file->f_mode & FMODE_WRITE) {
2151 if (file->f_flags & O_APPEND)
2152 av |= FILE__APPEND;
2153 else
2154 av |= FILE__WRITE;
2155 }
2156 if (!av) {
2157 /*
2158 * Special file opened with flags 3 for ioctl-only use.
2159 */
2160 av = FILE__IOCTL;
2161 }
2162
2163 return av;
2164}
2165
2166/*
2167 * Convert a file to an access vector and include the correct open
2168 * open permission.
2169 */
2170static inline u32 open_file_to_av(struct file *file)
2171{
2172 u32 av = file_to_av(file);
2173 struct inode *inode = file_inode(file);
2174
2175 if (selinux_policycap_openperm() &&
2176 inode->i_sb->s_magic != SOCKFS_MAGIC)
2177 av |= FILE__OPEN;
2178
2179 return av;
2180}
2181
2182/* Hook functions begin here. */
2183
2184static int selinux_binder_set_context_mgr(struct task_struct *mgr)
2185{
2186 u32 mysid = current_sid();
2187 u32 mgrsid = task_sid(mgr);
2188
2189 return avc_has_perm(&selinux_state,
2190 mysid, mgrsid, SECCLASS_BINDER,
2191 BINDER__SET_CONTEXT_MGR, NULL);
2192}
2193
2194static int selinux_binder_transaction(struct task_struct *from,
2195 struct task_struct *to)
2196{
2197 u32 mysid = current_sid();
2198 u32 fromsid = task_sid(from);
2199 u32 tosid = task_sid(to);
2200 int rc;
2201
2202 if (mysid != fromsid) {
2203 rc = avc_has_perm(&selinux_state,
2204 mysid, fromsid, SECCLASS_BINDER,
2205 BINDER__IMPERSONATE, NULL);
2206 if (rc)
2207 return rc;
2208 }
2209
2210 return avc_has_perm(&selinux_state,
2211 fromsid, tosid, SECCLASS_BINDER, BINDER__CALL,
2212 NULL);
2213}
2214
2215static int selinux_binder_transfer_binder(struct task_struct *from,
2216 struct task_struct *to)
2217{
2218 u32 fromsid = task_sid(from);
2219 u32 tosid = task_sid(to);
2220
2221 return avc_has_perm(&selinux_state,
2222 fromsid, tosid, SECCLASS_BINDER, BINDER__TRANSFER,
2223 NULL);
2224}
2225
2226static int selinux_binder_transfer_file(struct task_struct *from,
2227 struct task_struct *to,
2228 struct file *file)
2229{
2230 u32 sid = task_sid(to);
2231 struct file_security_struct *fsec = file->f_security;
2232 struct dentry *dentry = file->f_path.dentry;
2233 struct inode_security_struct *isec;
2234 struct common_audit_data ad;
2235 int rc;
2236
2237 ad.type = LSM_AUDIT_DATA_PATH;
2238 ad.u.path = file->f_path;
2239
2240 if (sid != fsec->sid) {
2241 rc = avc_has_perm(&selinux_state,
2242 sid, fsec->sid,
2243 SECCLASS_FD,
2244 FD__USE,
2245 &ad);
2246 if (rc)
2247 return rc;
2248 }
2249
2250#ifdef CONFIG_BPF_SYSCALL
2251 rc = bpf_fd_pass(file, sid);
2252 if (rc)
2253 return rc;
2254#endif
2255
2256 if (unlikely(IS_PRIVATE(d_backing_inode(dentry))))
2257 return 0;
2258
2259 isec = backing_inode_security(dentry);
2260 return avc_has_perm(&selinux_state,
2261 sid, isec->sid, isec->sclass, file_to_av(file),
2262 &ad);
2263}
2264
2265static int selinux_ptrace_access_check(struct task_struct *child,
2266 unsigned int mode)
2267{
2268 u32 sid = current_sid();
2269 u32 csid = task_sid(child);
2270
2271 if (mode & PTRACE_MODE_READ)
2272 return avc_has_perm(&selinux_state,
2273 sid, csid, SECCLASS_FILE, FILE__READ, NULL);
2274
2275 return avc_has_perm(&selinux_state,
2276 sid, csid, SECCLASS_PROCESS, PROCESS__PTRACE, NULL);
2277}
2278
2279static int selinux_ptrace_traceme(struct task_struct *parent)
2280{
2281 return avc_has_perm(&selinux_state,
2282 task_sid(parent), current_sid(), SECCLASS_PROCESS,
2283 PROCESS__PTRACE, NULL);
2284}
2285
2286static int selinux_capget(struct task_struct *target, kernel_cap_t *effective,
2287 kernel_cap_t *inheritable, kernel_cap_t *permitted)
2288{
2289 return avc_has_perm(&selinux_state,
2290 current_sid(), task_sid(target), SECCLASS_PROCESS,
2291 PROCESS__GETCAP, NULL);
2292}
2293
2294static int selinux_capset(struct cred *new, const struct cred *old,
2295 const kernel_cap_t *effective,
2296 const kernel_cap_t *inheritable,
2297 const kernel_cap_t *permitted)
2298{
2299 return avc_has_perm(&selinux_state,
2300 cred_sid(old), cred_sid(new), SECCLASS_PROCESS,
2301 PROCESS__SETCAP, NULL);
2302}
2303
2304/*
2305 * (This comment used to live with the selinux_task_setuid hook,
2306 * which was removed).
2307 *
2308 * Since setuid only affects the current process, and since the SELinux
2309 * controls are not based on the Linux identity attributes, SELinux does not
2310 * need to control this operation. However, SELinux does control the use of
2311 * the CAP_SETUID and CAP_SETGID capabilities using the capable hook.
2312 */
2313
2314static int selinux_capable(const struct cred *cred, struct user_namespace *ns,
2315 int cap, int audit)
2316{
2317 return cred_has_capability(cred, cap, audit, ns == &init_user_ns);
2318}
2319
2320static int selinux_quotactl(int cmds, int type, int id, struct super_block *sb)
2321{
2322 const struct cred *cred = current_cred();
2323 int rc = 0;
2324
2325 if (!sb)
2326 return 0;
2327
2328 switch (cmds) {
2329 case Q_SYNC:
2330 case Q_QUOTAON:
2331 case Q_QUOTAOFF:
2332 case Q_SETINFO:
2333 case Q_SETQUOTA:
2334 rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAMOD, NULL);
2335 break;
2336 case Q_GETFMT:
2337 case Q_GETINFO:
2338 case Q_GETQUOTA:
2339 rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAGET, NULL);
2340 break;
2341 default:
2342 rc = 0; /* let the kernel handle invalid cmds */
2343 break;
2344 }
2345 return rc;
2346}
2347
2348static int selinux_quota_on(struct dentry *dentry)
2349{
2350 const struct cred *cred = current_cred();
2351
2352 return dentry_has_perm(cred, dentry, FILE__QUOTAON);
2353}
2354
2355static int selinux_syslog(int type)
2356{
2357 switch (type) {
2358 case SYSLOG_ACTION_READ_ALL: /* Read last kernel messages */
2359 case SYSLOG_ACTION_SIZE_BUFFER: /* Return size of the log buffer */
2360 return avc_has_perm(&selinux_state,
2361 current_sid(), SECINITSID_KERNEL,
2362 SECCLASS_SYSTEM, SYSTEM__SYSLOG_READ, NULL);
2363 case SYSLOG_ACTION_CONSOLE_OFF: /* Disable logging to console */
2364 case SYSLOG_ACTION_CONSOLE_ON: /* Enable logging to console */
2365 /* Set level of messages printed to console */
2366 case SYSLOG_ACTION_CONSOLE_LEVEL:
2367 return avc_has_perm(&selinux_state,
2368 current_sid(), SECINITSID_KERNEL,
2369 SECCLASS_SYSTEM, SYSTEM__SYSLOG_CONSOLE,
2370 NULL);
2371 }
2372 /* All other syslog types */
2373 return avc_has_perm(&selinux_state,
2374 current_sid(), SECINITSID_KERNEL,
2375 SECCLASS_SYSTEM, SYSTEM__SYSLOG_MOD, NULL);
2376}
2377
2378/*
2379 * Check that a process has enough memory to allocate a new virtual
2380 * mapping. 0 means there is enough memory for the allocation to
2381 * succeed and -ENOMEM implies there is not.
2382 *
2383 * Do not audit the selinux permission check, as this is applied to all
2384 * processes that allocate mappings.
2385 */
2386static int selinux_vm_enough_memory(struct mm_struct *mm, long pages)
2387{
2388 int rc, cap_sys_admin = 0;
2389
2390 rc = cred_has_capability(current_cred(), CAP_SYS_ADMIN,
2391 SECURITY_CAP_NOAUDIT, true);
2392 if (rc == 0)
2393 cap_sys_admin = 1;
2394
2395 return cap_sys_admin;
2396}
2397
2398/* binprm security operations */
2399
2400static u32 ptrace_parent_sid(void)
2401{
2402 u32 sid = 0;
2403 struct task_struct *tracer;
2404
2405 rcu_read_lock();
2406 tracer = ptrace_parent(current);
2407 if (tracer)
2408 sid = task_sid(tracer);
2409 rcu_read_unlock();
2410
2411 return sid;
2412}
2413
2414static int check_nnp_nosuid(const struct linux_binprm *bprm,
2415 const struct task_security_struct *old_tsec,
2416 const struct task_security_struct *new_tsec)
2417{
2418 int nnp = (bprm->unsafe & LSM_UNSAFE_NO_NEW_PRIVS);
2419 int nosuid = !mnt_may_suid(bprm->file->f_path.mnt);
2420 int rc;
2421 u32 av;
2422
2423 if (!nnp && !nosuid)
2424 return 0; /* neither NNP nor nosuid */
2425
2426 if (new_tsec->sid == old_tsec->sid)
2427 return 0; /* No change in credentials */
2428
2429 /*
2430 * If the policy enables the nnp_nosuid_transition policy capability,
2431 * then we permit transitions under NNP or nosuid if the
2432 * policy allows the corresponding permission between
2433 * the old and new contexts.
2434 */
2435 if (selinux_policycap_nnp_nosuid_transition()) {
2436 av = 0;
2437 if (nnp)
2438 av |= PROCESS2__NNP_TRANSITION;
2439 if (nosuid)
2440 av |= PROCESS2__NOSUID_TRANSITION;
2441 rc = avc_has_perm(&selinux_state,
2442 old_tsec->sid, new_tsec->sid,
2443 SECCLASS_PROCESS2, av, NULL);
2444 if (!rc)
2445 return 0;
2446 }
2447
2448 /*
2449 * We also permit NNP or nosuid transitions to bounded SIDs,
2450 * i.e. SIDs that are guaranteed to only be allowed a subset
2451 * of the permissions of the current SID.
2452 */
2453 rc = security_bounded_transition(&selinux_state, old_tsec->sid,
2454 new_tsec->sid);
2455 if (!rc)
2456 return 0;
2457
2458 /*
2459 * On failure, preserve the errno values for NNP vs nosuid.
2460 * NNP: Operation not permitted for caller.
2461 * nosuid: Permission denied to file.
2462 */
2463 if (nnp)
2464 return -EPERM;
2465 return -EACCES;
2466}
2467
2468static int selinux_bprm_set_creds(struct linux_binprm *bprm)
2469{
2470 const struct task_security_struct *old_tsec;
2471 struct task_security_struct *new_tsec;
2472 struct inode_security_struct *isec;
2473 struct common_audit_data ad;
2474 struct inode *inode = file_inode(bprm->file);
2475 int rc;
2476
2477 /* SELinux context only depends on initial program or script and not
2478 * the script interpreter */
2479 if (bprm->called_set_creds)
2480 return 0;
2481
2482 old_tsec = current_security();
2483 new_tsec = bprm->cred->security;
2484 isec = inode_security(inode);
2485
2486 /* Default to the current task SID. */
2487 new_tsec->sid = old_tsec->sid;
2488 new_tsec->osid = old_tsec->sid;
2489
2490 /* Reset fs, key, and sock SIDs on execve. */
2491 new_tsec->create_sid = 0;
2492 new_tsec->keycreate_sid = 0;
2493 new_tsec->sockcreate_sid = 0;
2494
2495 if (old_tsec->exec_sid) {
2496 new_tsec->sid = old_tsec->exec_sid;
2497 /* Reset exec SID on execve. */
2498 new_tsec->exec_sid = 0;
2499
2500 /* Fail on NNP or nosuid if not an allowed transition. */
2501 rc = check_nnp_nosuid(bprm, old_tsec, new_tsec);
2502 if (rc)
2503 return rc;
2504 } else {
2505 /* Check for a default transition on this program. */
2506 rc = security_transition_sid(&selinux_state, old_tsec->sid,
2507 isec->sid, SECCLASS_PROCESS, NULL,
2508 &new_tsec->sid);
2509 if (rc)
2510 return rc;
2511
2512 /*
2513 * Fallback to old SID on NNP or nosuid if not an allowed
2514 * transition.
2515 */
2516 rc = check_nnp_nosuid(bprm, old_tsec, new_tsec);
2517 if (rc)
2518 new_tsec->sid = old_tsec->sid;
2519 }
2520
2521 ad.type = LSM_AUDIT_DATA_FILE;
2522 ad.u.file = bprm->file;
2523
2524 if (new_tsec->sid == old_tsec->sid) {
2525 rc = avc_has_perm(&selinux_state,
2526 old_tsec->sid, isec->sid,
2527 SECCLASS_FILE, FILE__EXECUTE_NO_TRANS, &ad);
2528 if (rc)
2529 return rc;
2530 } else {
2531 /* Check permissions for the transition. */
2532 rc = avc_has_perm(&selinux_state,
2533 old_tsec->sid, new_tsec->sid,
2534 SECCLASS_PROCESS, PROCESS__TRANSITION, &ad);
2535 if (rc)
2536 return rc;
2537
2538 rc = avc_has_perm(&selinux_state,
2539 new_tsec->sid, isec->sid,
2540 SECCLASS_FILE, FILE__ENTRYPOINT, &ad);
2541 if (rc)
2542 return rc;
2543
2544 /* Check for shared state */
2545 if (bprm->unsafe & LSM_UNSAFE_SHARE) {
2546 rc = avc_has_perm(&selinux_state,
2547 old_tsec->sid, new_tsec->sid,
2548 SECCLASS_PROCESS, PROCESS__SHARE,
2549 NULL);
2550 if (rc)
2551 return -EPERM;
2552 }
2553
2554 /* Make sure that anyone attempting to ptrace over a task that
2555 * changes its SID has the appropriate permit */
2556 if (bprm->unsafe & LSM_UNSAFE_PTRACE) {
2557 u32 ptsid = ptrace_parent_sid();
2558 if (ptsid != 0) {
2559 rc = avc_has_perm(&selinux_state,
2560 ptsid, new_tsec->sid,
2561 SECCLASS_PROCESS,
2562 PROCESS__PTRACE, NULL);
2563 if (rc)
2564 return -EPERM;
2565 }
2566 }
2567
2568 /* Clear any possibly unsafe personality bits on exec: */
2569 bprm->per_clear |= PER_CLEAR_ON_SETID;
2570
2571 /* Enable secure mode for SIDs transitions unless
2572 the noatsecure permission is granted between
2573 the two SIDs, i.e. ahp returns 0. */
2574 rc = avc_has_perm(&selinux_state,
2575 old_tsec->sid, new_tsec->sid,
2576 SECCLASS_PROCESS, PROCESS__NOATSECURE,
2577 NULL);
2578 bprm->secureexec |= !!rc;
2579 }
2580
2581 return 0;
2582}
2583
2584static int match_file(const void *p, struct file *file, unsigned fd)
2585{
2586 return file_has_perm(p, file, file_to_av(file)) ? fd + 1 : 0;
2587}
2588
2589/* Derived from fs/exec.c:flush_old_files. */
2590static inline void flush_unauthorized_files(const struct cred *cred,
2591 struct files_struct *files)
2592{
2593 struct file *file, *devnull = NULL;
2594 struct tty_struct *tty;
2595 int drop_tty = 0;
2596 unsigned n;
2597
2598 tty = get_current_tty();
2599 if (tty) {
2600 spin_lock(&tty->files_lock);
2601 if (!list_empty(&tty->tty_files)) {
2602 struct tty_file_private *file_priv;
2603
2604 /* Revalidate access to controlling tty.
2605 Use file_path_has_perm on the tty path directly
2606 rather than using file_has_perm, as this particular
2607 open file may belong to another process and we are
2608 only interested in the inode-based check here. */
2609 file_priv = list_first_entry(&tty->tty_files,
2610 struct tty_file_private, list);
2611 file = file_priv->file;
2612 if (file_path_has_perm(cred, file, FILE__READ | FILE__WRITE))
2613 drop_tty = 1;
2614 }
2615 spin_unlock(&tty->files_lock);
2616 tty_kref_put(tty);
2617 }
2618 /* Reset controlling tty. */
2619 if (drop_tty)
2620 no_tty();
2621
2622 /* Revalidate access to inherited open files. */
2623 n = iterate_fd(files, 0, match_file, cred);
2624 if (!n) /* none found? */
2625 return;
2626
2627 devnull = dentry_open(&selinux_null, O_RDWR, cred);
2628 if (IS_ERR(devnull))
2629 devnull = NULL;
2630 /* replace all the matching ones with this */
2631 do {
2632 replace_fd(n - 1, devnull, 0);
2633 } while ((n = iterate_fd(files, n, match_file, cred)) != 0);
2634 if (devnull)
2635 fput(devnull);
2636}
2637
2638/*
2639 * Prepare a process for imminent new credential changes due to exec
2640 */
2641static void selinux_bprm_committing_creds(struct linux_binprm *bprm)
2642{
2643 struct task_security_struct *new_tsec;
2644 struct rlimit *rlim, *initrlim;
2645 int rc, i;
2646
2647 new_tsec = bprm->cred->security;
2648 if (new_tsec->sid == new_tsec->osid)
2649 return;
2650
2651 /* Close files for which the new task SID is not authorized. */
2652 flush_unauthorized_files(bprm->cred, current->files);
2653
2654 /* Always clear parent death signal on SID transitions. */
2655 current->pdeath_signal = 0;
2656
2657 /* Check whether the new SID can inherit resource limits from the old
2658 * SID. If not, reset all soft limits to the lower of the current
2659 * task's hard limit and the init task's soft limit.
2660 *
2661 * Note that the setting of hard limits (even to lower them) can be
2662 * controlled by the setrlimit check. The inclusion of the init task's
2663 * soft limit into the computation is to avoid resetting soft limits
2664 * higher than the default soft limit for cases where the default is
2665 * lower than the hard limit, e.g. RLIMIT_CORE or RLIMIT_STACK.
2666 */
2667 rc = avc_has_perm(&selinux_state,
2668 new_tsec->osid, new_tsec->sid, SECCLASS_PROCESS,
2669 PROCESS__RLIMITINH, NULL);
2670 if (rc) {
2671 /* protect against do_prlimit() */
2672 task_lock(current);
2673 for (i = 0; i < RLIM_NLIMITS; i++) {
2674 rlim = current->signal->rlim + i;
2675 initrlim = init_task.signal->rlim + i;
2676 rlim->rlim_cur = min(rlim->rlim_max, initrlim->rlim_cur);
2677 }
2678 task_unlock(current);
2679 if (IS_ENABLED(CONFIG_POSIX_TIMERS))
2680 update_rlimit_cpu(current, rlimit(RLIMIT_CPU));
2681 }
2682}
2683
2684/*
2685 * Clean up the process immediately after the installation of new credentials
2686 * due to exec
2687 */
2688static void selinux_bprm_committed_creds(struct linux_binprm *bprm)
2689{
2690 const struct task_security_struct *tsec = current_security();
2691 struct itimerval itimer;
2692 u32 osid, sid;
2693 int rc, i;
2694
2695 osid = tsec->osid;
2696 sid = tsec->sid;
2697
2698 if (sid == osid)
2699 return;
2700
2701 /* Check whether the new SID can inherit signal state from the old SID.
2702 * If not, clear itimers to avoid subsequent signal generation and
2703 * flush and unblock signals.
2704 *
2705 * This must occur _after_ the task SID has been updated so that any
2706 * kill done after the flush will be checked against the new SID.
2707 */
2708 rc = avc_has_perm(&selinux_state,
2709 osid, sid, SECCLASS_PROCESS, PROCESS__SIGINH, NULL);
2710 if (rc) {
2711 if (IS_ENABLED(CONFIG_POSIX_TIMERS)) {
2712 memset(&itimer, 0, sizeof itimer);
2713 for (i = 0; i < 3; i++)
2714 do_setitimer(i, &itimer, NULL);
2715 }
2716 spin_lock_irq(¤t->sighand->siglock);
2717 if (!fatal_signal_pending(current)) {
2718 flush_sigqueue(¤t->pending);
2719 flush_sigqueue(¤t->signal->shared_pending);
2720 flush_signal_handlers(current, 1);
2721 sigemptyset(¤t->blocked);
2722 recalc_sigpending();
2723 }
2724 spin_unlock_irq(¤t->sighand->siglock);
2725 }
2726
2727 /* Wake up the parent if it is waiting so that it can recheck
2728 * wait permission to the new task SID. */
2729 read_lock(&tasklist_lock);
2730 __wake_up_parent(current, current->real_parent);
2731 read_unlock(&tasklist_lock);
2732}
2733
2734/* superblock security operations */
2735
2736static int selinux_sb_alloc_security(struct super_block *sb)
2737{
2738 return superblock_alloc_security(sb);
2739}
2740
2741static void selinux_sb_free_security(struct super_block *sb)
2742{
2743 superblock_free_security(sb);
2744}
2745
2746static inline int match_prefix(char *prefix, int plen, char *option, int olen)
2747{
2748 if (plen > olen)
2749 return 0;
2750
2751 return !memcmp(prefix, option, plen);
2752}
2753
2754static inline int selinux_option(char *option, int len)
2755{
2756 return (match_prefix(CONTEXT_STR, sizeof(CONTEXT_STR)-1, option, len) ||
2757 match_prefix(FSCONTEXT_STR, sizeof(FSCONTEXT_STR)-1, option, len) ||
2758 match_prefix(DEFCONTEXT_STR, sizeof(DEFCONTEXT_STR)-1, option, len) ||
2759 match_prefix(ROOTCONTEXT_STR, sizeof(ROOTCONTEXT_STR)-1, option, len) ||
2760 match_prefix(LABELSUPP_STR, sizeof(LABELSUPP_STR)-1, option, len));
2761}
2762
2763static inline void take_option(char **to, char *from, int *first, int len)
2764{
2765 if (!*first) {
2766 **to = ',';
2767 *to += 1;
2768 } else
2769 *first = 0;
2770 memcpy(*to, from, len);
2771 *to += len;
2772}
2773
2774static inline void take_selinux_option(char **to, char *from, int *first,
2775 int len)
2776{
2777 int current_size = 0;
2778
2779 if (!*first) {
2780 **to = '|';
2781 *to += 1;
2782 } else
2783 *first = 0;
2784
2785 while (current_size < len) {
2786 if (*from != '"') {
2787 **to = *from;
2788 *to += 1;
2789 }
2790 from += 1;
2791 current_size += 1;
2792 }
2793}
2794
2795static int selinux_sb_copy_data(char *orig, char *copy)
2796{
2797 int fnosec, fsec, rc = 0;
2798 char *in_save, *in_curr, *in_end;
2799 char *sec_curr, *nosec_save, *nosec;
2800 int open_quote = 0;
2801
2802 in_curr = orig;
2803 sec_curr = copy;
2804
2805 nosec = (char *)get_zeroed_page(GFP_KERNEL);
2806 if (!nosec) {
2807 rc = -ENOMEM;
2808 goto out;
2809 }
2810
2811 nosec_save = nosec;
2812 fnosec = fsec = 1;
2813 in_save = in_end = orig;
2814
2815 do {
2816 if (*in_end == '"')
2817 open_quote = !open_quote;
2818 if ((*in_end == ',' && open_quote == 0) ||
2819 *in_end == '\0') {
2820 int len = in_end - in_curr;
2821
2822 if (selinux_option(in_curr, len))
2823 take_selinux_option(&sec_curr, in_curr, &fsec, len);
2824 else
2825 take_option(&nosec, in_curr, &fnosec, len);
2826
2827 in_curr = in_end + 1;
2828 }
2829 } while (*in_end++);
2830
2831 strcpy(in_save, nosec_save);
2832 free_page((unsigned long)nosec_save);
2833out:
2834 return rc;
2835}
2836
2837static int selinux_sb_remount(struct super_block *sb, void *data)
2838{
2839 int rc, i, *flags;
2840 struct security_mnt_opts opts;
2841 char *secdata, **mount_options;
2842 struct superblock_security_struct *sbsec = sb->s_security;
2843
2844 if (!(sbsec->flags & SE_SBINITIALIZED))
2845 return 0;
2846
2847 if (!data)
2848 return 0;
2849
2850 if (sb->s_type->fs_flags & FS_BINARY_MOUNTDATA)
2851 return 0;
2852
2853 security_init_mnt_opts(&opts);
2854 secdata = alloc_secdata();
2855 if (!secdata)
2856 return -ENOMEM;
2857 rc = selinux_sb_copy_data(data, secdata);
2858 if (rc)
2859 goto out_free_secdata;
2860
2861 rc = selinux_parse_opts_str(secdata, &opts);
2862 if (rc)
2863 goto out_free_secdata;
2864
2865 mount_options = opts.mnt_opts;
2866 flags = opts.mnt_opts_flags;
2867
2868 for (i = 0; i < opts.num_mnt_opts; i++) {
2869 u32 sid;
2870
2871 if (flags[i] == SBLABEL_MNT)
2872 continue;
2873 rc = security_context_str_to_sid(&selinux_state,
2874 mount_options[i], &sid,
2875 GFP_KERNEL);
2876 if (rc) {
2877 printk(KERN_WARNING "SELinux: security_context_str_to_sid"
2878 "(%s) failed for (dev %s, type %s) errno=%d\n",
2879 mount_options[i], sb->s_id, sb->s_type->name, rc);
2880 goto out_free_opts;
2881 }
2882 rc = -EINVAL;
2883 switch (flags[i]) {
2884 case FSCONTEXT_MNT:
2885 if (bad_option(sbsec, FSCONTEXT_MNT, sbsec->sid, sid))
2886 goto out_bad_option;
2887 break;
2888 case CONTEXT_MNT:
2889 if (bad_option(sbsec, CONTEXT_MNT, sbsec->mntpoint_sid, sid))
2890 goto out_bad_option;
2891 break;
2892 case ROOTCONTEXT_MNT: {
2893 struct inode_security_struct *root_isec;
2894 root_isec = backing_inode_security(sb->s_root);
2895
2896 if (bad_option(sbsec, ROOTCONTEXT_MNT, root_isec->sid, sid))
2897 goto out_bad_option;
2898 break;
2899 }
2900 case DEFCONTEXT_MNT:
2901 if (bad_option(sbsec, DEFCONTEXT_MNT, sbsec->def_sid, sid))
2902 goto out_bad_option;
2903 break;
2904 default:
2905 goto out_free_opts;
2906 }
2907 }
2908
2909 rc = 0;
2910out_free_opts:
2911 security_free_mnt_opts(&opts);
2912out_free_secdata:
2913 free_secdata(secdata);
2914 return rc;
2915out_bad_option:
2916 printk(KERN_WARNING "SELinux: unable to change security options "
2917 "during remount (dev %s, type=%s)\n", sb->s_id,
2918 sb->s_type->name);
2919 goto out_free_opts;
2920}
2921
2922static int selinux_sb_kern_mount(struct super_block *sb, int flags, void *data)
2923{
2924 const struct cred *cred = current_cred();
2925 struct common_audit_data ad;
2926 int rc;
2927
2928 rc = superblock_doinit(sb, data);
2929 if (rc)
2930 return rc;
2931
2932 /* Allow all mounts performed by the kernel */
2933 if (flags & MS_KERNMOUNT)
2934 return 0;
2935
2936 ad.type = LSM_AUDIT_DATA_DENTRY;
2937 ad.u.dentry = sb->s_root;
2938 return superblock_has_perm(cred, sb, FILESYSTEM__MOUNT, &ad);
2939}
2940
2941static int selinux_sb_statfs(struct dentry *dentry)
2942{
2943 const struct cred *cred = current_cred();
2944 struct common_audit_data ad;
2945
2946 ad.type = LSM_AUDIT_DATA_DENTRY;
2947 ad.u.dentry = dentry->d_sb->s_root;
2948 return superblock_has_perm(cred, dentry->d_sb, FILESYSTEM__GETATTR, &ad);
2949}
2950
2951static int selinux_mount(const char *dev_name,
2952 const struct path *path,
2953 const char *type,
2954 unsigned long flags,
2955 void *data)
2956{
2957 const struct cred *cred = current_cred();
2958
2959 if (flags & MS_REMOUNT)
2960 return superblock_has_perm(cred, path->dentry->d_sb,
2961 FILESYSTEM__REMOUNT, NULL);
2962 else
2963 return path_has_perm(cred, path, FILE__MOUNTON);
2964}
2965
2966static int selinux_umount(struct vfsmount *mnt, int flags)
2967{
2968 const struct cred *cred = current_cred();
2969
2970 return superblock_has_perm(cred, mnt->mnt_sb,
2971 FILESYSTEM__UNMOUNT, NULL);
2972}
2973
2974/* inode security operations */
2975
2976static int selinux_inode_alloc_security(struct inode *inode)
2977{
2978 return inode_alloc_security(inode);
2979}
2980
2981static void selinux_inode_free_security(struct inode *inode)
2982{
2983 inode_free_security(inode);
2984}
2985
2986static int selinux_dentry_init_security(struct dentry *dentry, int mode,
2987 const struct qstr *name, void **ctx,
2988 u32 *ctxlen)
2989{
2990 u32 newsid;
2991 int rc;
2992
2993 rc = selinux_determine_inode_label(current_security(),
2994 d_inode(dentry->d_parent), name,
2995 inode_mode_to_security_class(mode),
2996 &newsid);
2997 if (rc)
2998 return rc;
2999
3000 return security_sid_to_context(&selinux_state, newsid, (char **)ctx,
3001 ctxlen);
3002}
3003
3004static int selinux_dentry_create_files_as(struct dentry *dentry, int mode,
3005 struct qstr *name,
3006 const struct cred *old,
3007 struct cred *new)
3008{
3009 u32 newsid;
3010 int rc;
3011 struct task_security_struct *tsec;
3012
3013 rc = selinux_determine_inode_label(old->security,
3014 d_inode(dentry->d_parent), name,
3015 inode_mode_to_security_class(mode),
3016 &newsid);
3017 if (rc)
3018 return rc;
3019
3020 tsec = new->security;
3021 tsec->create_sid = newsid;
3022 return 0;
3023}
3024
3025static int selinux_inode_init_security(struct inode *inode, struct inode *dir,
3026 const struct qstr *qstr,
3027 const char **name,
3028 void **value, size_t *len)
3029{
3030 const struct task_security_struct *tsec = current_security();
3031 struct superblock_security_struct *sbsec;
3032 u32 newsid, clen;
3033 int rc;
3034 char *context;
3035
3036 sbsec = dir->i_sb->s_security;
3037
3038 newsid = tsec->create_sid;
3039
3040 rc = selinux_determine_inode_label(current_security(),
3041 dir, qstr,
3042 inode_mode_to_security_class(inode->i_mode),
3043 &newsid);
3044 if (rc)
3045 return rc;
3046
3047 /* Possibly defer initialization to selinux_complete_init. */
3048 if (sbsec->flags & SE_SBINITIALIZED) {
3049 struct inode_security_struct *isec = inode->i_security;
3050 isec->sclass = inode_mode_to_security_class(inode->i_mode);
3051 isec->sid = newsid;
3052 isec->initialized = LABEL_INITIALIZED;
3053 }
3054
3055 if (!selinux_state.initialized || !(sbsec->flags & SBLABEL_MNT))
3056 return -EOPNOTSUPP;
3057
3058 if (name)
3059 *name = XATTR_SELINUX_SUFFIX;
3060
3061 if (value && len) {
3062 rc = security_sid_to_context_force(&selinux_state, newsid,
3063 &context, &clen);
3064 if (rc)
3065 return rc;
3066 *value = context;
3067 *len = clen;
3068 }
3069
3070 return 0;
3071}
3072
3073static int selinux_inode_create(struct inode *dir, struct dentry *dentry, umode_t mode)
3074{
3075 return may_create(dir, dentry, SECCLASS_FILE);
3076}
3077
3078static int selinux_inode_link(struct dentry *old_dentry, struct inode *dir, struct dentry *new_dentry)
3079{
3080 return may_link(dir, old_dentry, MAY_LINK);
3081}
3082
3083static int selinux_inode_unlink(struct inode *dir, struct dentry *dentry)
3084{
3085 return may_link(dir, dentry, MAY_UNLINK);
3086}
3087
3088static int selinux_inode_symlink(struct inode *dir, struct dentry *dentry, const char *name)
3089{
3090 return may_create(dir, dentry, SECCLASS_LNK_FILE);
3091}
3092
3093static int selinux_inode_mkdir(struct inode *dir, struct dentry *dentry, umode_t mask)
3094{
3095 return may_create(dir, dentry, SECCLASS_DIR);
3096}
3097
3098static int selinux_inode_rmdir(struct inode *dir, struct dentry *dentry)
3099{
3100 return may_link(dir, dentry, MAY_RMDIR);
3101}
3102
3103static int selinux_inode_mknod(struct inode *dir, struct dentry *dentry, umode_t mode, dev_t dev)
3104{
3105 return may_create(dir, dentry, inode_mode_to_security_class(mode));
3106}
3107
3108static int selinux_inode_rename(struct inode *old_inode, struct dentry *old_dentry,
3109 struct inode *new_inode, struct dentry *new_dentry)
3110{
3111 return may_rename(old_inode, old_dentry, new_inode, new_dentry);
3112}
3113
3114static int selinux_inode_readlink(struct dentry *dentry)
3115{
3116 const struct cred *cred = current_cred();
3117
3118 return dentry_has_perm(cred, dentry, FILE__READ);
3119}
3120
3121static int selinux_inode_follow_link(struct dentry *dentry, struct inode *inode,
3122 bool rcu)
3123{
3124 const struct cred *cred = current_cred();
3125 struct common_audit_data ad;
3126 struct inode_security_struct *isec;
3127 u32 sid;
3128
3129 validate_creds(cred);
3130
3131 ad.type = LSM_AUDIT_DATA_DENTRY;
3132 ad.u.dentry = dentry;
3133 sid = cred_sid(cred);
3134 isec = inode_security_rcu(inode, rcu);
3135 if (IS_ERR(isec))
3136 return PTR_ERR(isec);
3137
3138 return avc_has_perm_flags(&selinux_state,
3139 sid, isec->sid, isec->sclass, FILE__READ, &ad,
3140 rcu ? MAY_NOT_BLOCK : 0);
3141}
3142
3143static noinline int audit_inode_permission(struct inode *inode,
3144 u32 perms, u32 audited, u32 denied,
3145 int result,
3146 unsigned flags)
3147{
3148 struct common_audit_data ad;
3149 struct inode_security_struct *isec = inode->i_security;
3150 int rc;
3151
3152 ad.type = LSM_AUDIT_DATA_INODE;
3153 ad.u.inode = inode;
3154
3155 rc = slow_avc_audit(&selinux_state,
3156 current_sid(), isec->sid, isec->sclass, perms,
3157 audited, denied, result, &ad, flags);
3158 if (rc)
3159 return rc;
3160 return 0;
3161}
3162
3163static int selinux_inode_permission(struct inode *inode, int mask)
3164{
3165 const struct cred *cred = current_cred();
3166 u32 perms;
3167 bool from_access;
3168 unsigned flags = mask & MAY_NOT_BLOCK;
3169 struct inode_security_struct *isec;
3170 u32 sid;
3171 struct av_decision avd;
3172 int rc, rc2;
3173 u32 audited, denied;
3174
3175 from_access = mask & MAY_ACCESS;
3176 mask &= (MAY_READ|MAY_WRITE|MAY_EXEC|MAY_APPEND);
3177
3178 /* No permission to check. Existence test. */
3179 if (!mask)
3180 return 0;
3181
3182 validate_creds(cred);
3183
3184 if (unlikely(IS_PRIVATE(inode)))
3185 return 0;
3186
3187 perms = file_mask_to_av(inode->i_mode, mask);
3188
3189 sid = cred_sid(cred);
3190 isec = inode_security_rcu(inode, flags & MAY_NOT_BLOCK);
3191 if (IS_ERR(isec))
3192 return PTR_ERR(isec);
3193
3194 rc = avc_has_perm_noaudit(&selinux_state,
3195 sid, isec->sid, isec->sclass, perms, 0, &avd);
3196 audited = avc_audit_required(perms, &avd, rc,
3197 from_access ? FILE__AUDIT_ACCESS : 0,
3198 &denied);
3199 if (likely(!audited))
3200 return rc;
3201
3202 rc2 = audit_inode_permission(inode, perms, audited, denied, rc, flags);
3203 if (rc2)
3204 return rc2;
3205 return rc;
3206}
3207
3208static int selinux_inode_setattr(struct dentry *dentry, struct iattr *iattr)
3209{
3210 const struct cred *cred = current_cred();
3211 struct inode *inode = d_backing_inode(dentry);
3212 unsigned int ia_valid = iattr->ia_valid;
3213 __u32 av = FILE__WRITE;
3214
3215 /* ATTR_FORCE is just used for ATTR_KILL_S[UG]ID. */
3216 if (ia_valid & ATTR_FORCE) {
3217 ia_valid &= ~(ATTR_KILL_SUID | ATTR_KILL_SGID | ATTR_MODE |
3218 ATTR_FORCE);
3219 if (!ia_valid)
3220 return 0;
3221 }
3222
3223 if (ia_valid & (ATTR_MODE | ATTR_UID | ATTR_GID |
3224 ATTR_ATIME_SET | ATTR_MTIME_SET | ATTR_TIMES_SET))
3225 return dentry_has_perm(cred, dentry, FILE__SETATTR);
3226
3227 if (selinux_policycap_openperm() &&
3228 inode->i_sb->s_magic != SOCKFS_MAGIC &&
3229 (ia_valid & ATTR_SIZE) &&
3230 !(ia_valid & ATTR_FILE))
3231 av |= FILE__OPEN;
3232
3233 return dentry_has_perm(cred, dentry, av);
3234}
3235
3236static int selinux_inode_getattr(const struct path *path)
3237{
3238 return path_has_perm(current_cred(), path, FILE__GETATTR);
3239}
3240
3241static bool has_cap_mac_admin(bool audit)
3242{
3243 const struct cred *cred = current_cred();
3244 int cap_audit = audit ? SECURITY_CAP_AUDIT : SECURITY_CAP_NOAUDIT;
3245
3246 if (cap_capable(cred, &init_user_ns, CAP_MAC_ADMIN, cap_audit))
3247 return false;
3248 if (cred_has_capability(cred, CAP_MAC_ADMIN, cap_audit, true))
3249 return false;
3250 return true;
3251}
3252
3253static int selinux_inode_setxattr(struct dentry *dentry, const char *name,
3254 const void *value, size_t size, int flags)
3255{
3256 struct inode *inode = d_backing_inode(dentry);
3257 struct inode_security_struct *isec;
3258 struct superblock_security_struct *sbsec;
3259 struct common_audit_data ad;
3260 u32 newsid, sid = current_sid();
3261 int rc = 0;
3262
3263 if (strcmp(name, XATTR_NAME_SELINUX)) {
3264 rc = cap_inode_setxattr(dentry, name, value, size, flags);
3265 if (rc)
3266 return rc;
3267
3268 /* Not an attribute we recognize, so just check the
3269 ordinary setattr permission. */
3270 return dentry_has_perm(current_cred(), dentry, FILE__SETATTR);
3271 }
3272
3273 sbsec = inode->i_sb->s_security;
3274 if (!(sbsec->flags & SBLABEL_MNT))
3275 return -EOPNOTSUPP;
3276
3277 if (!inode_owner_or_capable(inode))
3278 return -EPERM;
3279
3280 ad.type = LSM_AUDIT_DATA_DENTRY;
3281 ad.u.dentry = dentry;
3282
3283 isec = backing_inode_security(dentry);
3284 rc = avc_has_perm(&selinux_state,
3285 sid, isec->sid, isec->sclass,
3286 FILE__RELABELFROM, &ad);
3287 if (rc)
3288 return rc;
3289
3290 rc = security_context_to_sid(&selinux_state, value, size, &newsid,
3291 GFP_KERNEL);
3292 if (rc == -EINVAL) {
3293 if (!has_cap_mac_admin(true)) {
3294 struct audit_buffer *ab;
3295 size_t audit_size;
3296
3297 /* We strip a nul only if it is at the end, otherwise the
3298 * context contains a nul and we should audit that */
3299 if (value) {
3300 const char *str = value;
3301
3302 if (str[size - 1] == '\0')
3303 audit_size = size - 1;
3304 else
3305 audit_size = size;
3306 } else {
3307 audit_size = 0;
3308 }
3309 ab = audit_log_start(current->audit_context, GFP_ATOMIC, AUDIT_SELINUX_ERR);
3310 audit_log_format(ab, "op=setxattr invalid_context=");
3311 audit_log_n_untrustedstring(ab, value, audit_size);
3312 audit_log_end(ab);
3313
3314 return rc;
3315 }
3316 rc = security_context_to_sid_force(&selinux_state, value,
3317 size, &newsid);
3318 }
3319 if (rc)
3320 return rc;
3321
3322 rc = avc_has_perm(&selinux_state,
3323 sid, newsid, isec->sclass,
3324 FILE__RELABELTO, &ad);
3325 if (rc)
3326 return rc;
3327
3328 rc = security_validate_transition(&selinux_state, isec->sid, newsid,
3329 sid, isec->sclass);
3330 if (rc)
3331 return rc;
3332
3333 return avc_has_perm(&selinux_state,
3334 newsid,
3335 sbsec->sid,
3336 SECCLASS_FILESYSTEM,
3337 FILESYSTEM__ASSOCIATE,
3338 &ad);
3339}
3340
3341static void selinux_inode_post_setxattr(struct dentry *dentry, const char *name,
3342 const void *value, size_t size,
3343 int flags)
3344{
3345 struct inode *inode = d_backing_inode(dentry);
3346 struct inode_security_struct *isec;
3347 u32 newsid;
3348 int rc;
3349
3350 if (strcmp(name, XATTR_NAME_SELINUX)) {
3351 /* Not an attribute we recognize, so nothing to do. */
3352 return;
3353 }
3354
3355 rc = security_context_to_sid_force(&selinux_state, value, size,
3356 &newsid);
3357 if (rc) {
3358 printk(KERN_ERR "SELinux: unable to map context to SID"
3359 "for (%s, %lu), rc=%d\n",
3360 inode->i_sb->s_id, inode->i_ino, -rc);
3361 return;
3362 }
3363
3364 isec = backing_inode_security(dentry);
3365 spin_lock(&isec->lock);
3366 isec->sclass = inode_mode_to_security_class(inode->i_mode);
3367 isec->sid = newsid;
3368 isec->initialized = LABEL_INITIALIZED;
3369 spin_unlock(&isec->lock);
3370
3371 return;
3372}
3373
3374static int selinux_inode_getxattr(struct dentry *dentry, const char *name)
3375{
3376 const struct cred *cred = current_cred();
3377
3378 return dentry_has_perm(cred, dentry, FILE__GETATTR);
3379}
3380
3381static int selinux_inode_listxattr(struct dentry *dentry)
3382{
3383 const struct cred *cred = current_cred();
3384
3385 return dentry_has_perm(cred, dentry, FILE__GETATTR);
3386}
3387
3388static int selinux_inode_removexattr(struct dentry *dentry, const char *name)
3389{
3390 if (strcmp(name, XATTR_NAME_SELINUX)) {
3391 int rc = cap_inode_removexattr(dentry, name);
3392 if (rc)
3393 return rc;
3394
3395 /* Not an attribute we recognize, so just check the
3396 ordinary setattr permission. */
3397 return dentry_has_perm(current_cred(), dentry, FILE__SETATTR);
3398 }
3399
3400 /* No one is allowed to remove a SELinux security label.
3401 You can change the label, but all data must be labeled. */
3402 return -EACCES;
3403}
3404
3405/*
3406 * Copy the inode security context value to the user.
3407 *
3408 * Permission check is handled by selinux_inode_getxattr hook.
3409 */
3410static int selinux_inode_getsecurity(struct inode *inode, const char *name, void **buffer, bool alloc)
3411{
3412 u32 size;
3413 int error;
3414 char *context = NULL;
3415 struct inode_security_struct *isec;
3416
3417 if (strcmp(name, XATTR_SELINUX_SUFFIX))
3418 return -EOPNOTSUPP;
3419
3420 /*
3421 * If the caller has CAP_MAC_ADMIN, then get the raw context
3422 * value even if it is not defined by current policy; otherwise,
3423 * use the in-core value under current policy.
3424 * Use the non-auditing forms of the permission checks since
3425 * getxattr may be called by unprivileged processes commonly
3426 * and lack of permission just means that we fall back to the
3427 * in-core context value, not a denial.
3428 */
3429 isec = inode_security(inode);
3430 if (has_cap_mac_admin(false))
3431 error = security_sid_to_context_force(&selinux_state,
3432 isec->sid, &context,
3433 &size);
3434 else
3435 error = security_sid_to_context(&selinux_state, isec->sid,
3436 &context, &size);
3437 if (error)
3438 return error;
3439 error = size;
3440 if (alloc) {
3441 *buffer = context;
3442 goto out_nofree;
3443 }
3444 kfree(context);
3445out_nofree:
3446 return error;
3447}
3448
3449static int selinux_inode_setsecurity(struct inode *inode, const char *name,
3450 const void *value, size_t size, int flags)
3451{
3452 struct inode_security_struct *isec = inode_security_novalidate(inode);
3453 u32 newsid;
3454 int rc;
3455
3456 if (strcmp(name, XATTR_SELINUX_SUFFIX))
3457 return -EOPNOTSUPP;
3458
3459 if (!value || !size)
3460 return -EACCES;
3461
3462 rc = security_context_to_sid(&selinux_state, value, size, &newsid,
3463 GFP_KERNEL);
3464 if (rc)
3465 return rc;
3466
3467 spin_lock(&isec->lock);
3468 isec->sclass = inode_mode_to_security_class(inode->i_mode);
3469 isec->sid = newsid;
3470 isec->initialized = LABEL_INITIALIZED;
3471 spin_unlock(&isec->lock);
3472 return 0;
3473}
3474
3475static int selinux_inode_listsecurity(struct inode *inode, char *buffer, size_t buffer_size)
3476{
3477 const int len = sizeof(XATTR_NAME_SELINUX);
3478 if (buffer && len <= buffer_size)
3479 memcpy(buffer, XATTR_NAME_SELINUX, len);
3480 return len;
3481}
3482
3483static void selinux_inode_getsecid(struct inode *inode, u32 *secid)
3484{
3485 struct inode_security_struct *isec = inode_security_novalidate(inode);
3486 *secid = isec->sid;
3487}
3488
3489static int selinux_inode_copy_up(struct dentry *src, struct cred **new)
3490{
3491 u32 sid;
3492 struct task_security_struct *tsec;
3493 struct cred *new_creds = *new;
3494
3495 if (new_creds == NULL) {
3496 new_creds = prepare_creds();
3497 if (!new_creds)
3498 return -ENOMEM;
3499 }
3500
3501 tsec = new_creds->security;
3502 /* Get label from overlay inode and set it in create_sid */
3503 selinux_inode_getsecid(d_inode(src), &sid);
3504 tsec->create_sid = sid;
3505 *new = new_creds;
3506 return 0;
3507}
3508
3509static int selinux_inode_copy_up_xattr(const char *name)
3510{
3511 /* The copy_up hook above sets the initial context on an inode, but we
3512 * don't then want to overwrite it by blindly copying all the lower
3513 * xattrs up. Instead, we have to filter out SELinux-related xattrs.
3514 */
3515 if (strcmp(name, XATTR_NAME_SELINUX) == 0)
3516 return 1; /* Discard */
3517 /*
3518 * Any other attribute apart from SELINUX is not claimed, supported
3519 * by selinux.
3520 */
3521 return -EOPNOTSUPP;
3522}
3523
3524/* file security operations */
3525
3526static int selinux_revalidate_file_permission(struct file *file, int mask)
3527{
3528 const struct cred *cred = current_cred();
3529 struct inode *inode = file_inode(file);
3530
3531 /* file_mask_to_av won't add FILE__WRITE if MAY_APPEND is set */
3532 if ((file->f_flags & O_APPEND) && (mask & MAY_WRITE))
3533 mask |= MAY_APPEND;
3534
3535 return file_has_perm(cred, file,
3536 file_mask_to_av(inode->i_mode, mask));
3537}
3538
3539static int selinux_file_permission(struct file *file, int mask)
3540{
3541 struct inode *inode = file_inode(file);
3542 struct file_security_struct *fsec = file->f_security;
3543 struct inode_security_struct *isec;
3544 u32 sid = current_sid();
3545
3546 if (!mask)
3547 /* No permission to check. Existence test. */
3548 return 0;
3549
3550 isec = inode_security(inode);
3551 if (sid == fsec->sid && fsec->isid == isec->sid &&
3552 fsec->pseqno == avc_policy_seqno(&selinux_state))
3553 /* No change since file_open check. */
3554 return 0;
3555
3556 return selinux_revalidate_file_permission(file, mask);
3557}
3558
3559static int selinux_file_alloc_security(struct file *file)
3560{
3561 return file_alloc_security(file);
3562}
3563
3564static void selinux_file_free_security(struct file *file)
3565{
3566 file_free_security(file);
3567}
3568
3569/*
3570 * Check whether a task has the ioctl permission and cmd
3571 * operation to an inode.
3572 */
3573static int ioctl_has_perm(const struct cred *cred, struct file *file,
3574 u32 requested, u16 cmd)
3575{
3576 struct common_audit_data ad;
3577 struct file_security_struct *fsec = file->f_security;
3578 struct inode *inode = file_inode(file);
3579 struct inode_security_struct *isec;
3580 struct lsm_ioctlop_audit ioctl;
3581 u32 ssid = cred_sid(cred);
3582 int rc;
3583 u8 driver = cmd >> 8;
3584 u8 xperm = cmd & 0xff;
3585
3586 ad.type = LSM_AUDIT_DATA_IOCTL_OP;
3587 ad.u.op = &ioctl;
3588 ad.u.op->cmd = cmd;
3589 ad.u.op->path = file->f_path;
3590
3591 if (ssid != fsec->sid) {
3592 rc = avc_has_perm(&selinux_state,
3593 ssid, fsec->sid,
3594 SECCLASS_FD,
3595 FD__USE,
3596 &ad);
3597 if (rc)
3598 goto out;
3599 }
3600
3601 if (unlikely(IS_PRIVATE(inode)))
3602 return 0;
3603
3604 isec = inode_security(inode);
3605 rc = avc_has_extended_perms(&selinux_state,
3606 ssid, isec->sid, isec->sclass,
3607 requested, driver, xperm, &ad);
3608out:
3609 return rc;
3610}
3611
3612static int selinux_file_ioctl(struct file *file, unsigned int cmd,
3613 unsigned long arg)
3614{
3615 const struct cred *cred = current_cred();
3616 int error = 0;
3617
3618 switch (cmd) {
3619 case FIONREAD:
3620 /* fall through */
3621 case FIBMAP:
3622 /* fall through */
3623 case FIGETBSZ:
3624 /* fall through */
3625 case FS_IOC_GETFLAGS:
3626 /* fall through */
3627 case FS_IOC_GETVERSION:
3628 error = file_has_perm(cred, file, FILE__GETATTR);
3629 break;
3630
3631 case FS_IOC_SETFLAGS:
3632 /* fall through */
3633 case FS_IOC_SETVERSION:
3634 error = file_has_perm(cred, file, FILE__SETATTR);
3635 break;
3636
3637 /* sys_ioctl() checks */
3638 case FIONBIO:
3639 /* fall through */
3640 case FIOASYNC:
3641 error = file_has_perm(cred, file, 0);
3642 break;
3643
3644 case KDSKBENT:
3645 case KDSKBSENT:
3646 error = cred_has_capability(cred, CAP_SYS_TTY_CONFIG,
3647 SECURITY_CAP_AUDIT, true);
3648 break;
3649
3650 /* default case assumes that the command will go
3651 * to the file's ioctl() function.
3652 */
3653 default:
3654 error = ioctl_has_perm(cred, file, FILE__IOCTL, (u16) cmd);
3655 }
3656 return error;
3657}
3658
3659static int default_noexec;
3660
3661static int file_map_prot_check(struct file *file, unsigned long prot, int shared)
3662{
3663 const struct cred *cred = current_cred();
3664 u32 sid = cred_sid(cred);
3665 int rc = 0;
3666
3667 if (default_noexec &&
3668 (prot & PROT_EXEC) && (!file || IS_PRIVATE(file_inode(file)) ||
3669 (!shared && (prot & PROT_WRITE)))) {
3670 /*
3671 * We are making executable an anonymous mapping or a
3672 * private file mapping that will also be writable.
3673 * This has an additional check.
3674 */
3675 rc = avc_has_perm(&selinux_state,
3676 sid, sid, SECCLASS_PROCESS,
3677 PROCESS__EXECMEM, NULL);
3678 if (rc)
3679 goto error;
3680 }
3681
3682 if (file) {
3683 /* read access is always possible with a mapping */
3684 u32 av = FILE__READ;
3685
3686 /* write access only matters if the mapping is shared */
3687 if (shared && (prot & PROT_WRITE))
3688 av |= FILE__WRITE;
3689
3690 if (prot & PROT_EXEC)
3691 av |= FILE__EXECUTE;
3692
3693 return file_has_perm(cred, file, av);
3694 }
3695
3696error:
3697 return rc;
3698}
3699
3700static int selinux_mmap_addr(unsigned long addr)
3701{
3702 int rc = 0;
3703
3704 if (addr < CONFIG_LSM_MMAP_MIN_ADDR) {
3705 u32 sid = current_sid();
3706 rc = avc_has_perm(&selinux_state,
3707 sid, sid, SECCLASS_MEMPROTECT,
3708 MEMPROTECT__MMAP_ZERO, NULL);
3709 }
3710
3711 return rc;
3712}
3713
3714static int selinux_mmap_file(struct file *file, unsigned long reqprot,
3715 unsigned long prot, unsigned long flags)
3716{
3717 struct common_audit_data ad;
3718 int rc;
3719
3720 if (file) {
3721 ad.type = LSM_AUDIT_DATA_FILE;
3722 ad.u.file = file;
3723 rc = inode_has_perm(current_cred(), file_inode(file),
3724 FILE__MAP, &ad);
3725 if (rc)
3726 return rc;
3727 }
3728
3729 if (selinux_state.checkreqprot)
3730 prot = reqprot;
3731
3732 return file_map_prot_check(file, prot,
3733 (flags & MAP_TYPE) == MAP_SHARED);
3734}
3735
3736static int selinux_file_mprotect(struct vm_area_struct *vma,
3737 unsigned long reqprot,
3738 unsigned long prot)
3739{
3740 const struct cred *cred = current_cred();
3741 u32 sid = cred_sid(cred);
3742
3743 if (selinux_state.checkreqprot)
3744 prot = reqprot;
3745
3746 if (default_noexec &&
3747 (prot & PROT_EXEC) && !(vma->vm_flags & VM_EXEC)) {
3748 int rc = 0;
3749 if (vma->vm_start >= vma->vm_mm->start_brk &&
3750 vma->vm_end <= vma->vm_mm->brk) {
3751 rc = avc_has_perm(&selinux_state,
3752 sid, sid, SECCLASS_PROCESS,
3753 PROCESS__EXECHEAP, NULL);
3754 } else if (!vma->vm_file &&
3755 ((vma->vm_start <= vma->vm_mm->start_stack &&
3756 vma->vm_end >= vma->vm_mm->start_stack) ||
3757 vma_is_stack_for_current(vma))) {
3758 rc = avc_has_perm(&selinux_state,
3759 sid, sid, SECCLASS_PROCESS,
3760 PROCESS__EXECSTACK, NULL);
3761 } else if (vma->vm_file && vma->anon_vma) {
3762 /*
3763 * We are making executable a file mapping that has
3764 * had some COW done. Since pages might have been
3765 * written, check ability to execute the possibly
3766 * modified content. This typically should only
3767 * occur for text relocations.
3768 */
3769 rc = file_has_perm(cred, vma->vm_file, FILE__EXECMOD);
3770 }
3771 if (rc)
3772 return rc;
3773 }
3774
3775 return file_map_prot_check(vma->vm_file, prot, vma->vm_flags&VM_SHARED);
3776}
3777
3778static int selinux_file_lock(struct file *file, unsigned int cmd)
3779{
3780 const struct cred *cred = current_cred();
3781
3782 return file_has_perm(cred, file, FILE__LOCK);
3783}
3784
3785static int selinux_file_fcntl(struct file *file, unsigned int cmd,
3786 unsigned long arg)
3787{
3788 const struct cred *cred = current_cred();
3789 int err = 0;
3790
3791 switch (cmd) {
3792 case F_SETFL:
3793 if ((file->f_flags & O_APPEND) && !(arg & O_APPEND)) {
3794 err = file_has_perm(cred, file, FILE__WRITE);
3795 break;
3796 }
3797 /* fall through */
3798 case F_SETOWN:
3799 case F_SETSIG:
3800 case F_GETFL:
3801 case F_GETOWN:
3802 case F_GETSIG:
3803 case F_GETOWNER_UIDS:
3804 /* Just check FD__USE permission */
3805 err = file_has_perm(cred, file, 0);
3806 break;
3807 case F_GETLK:
3808 case F_SETLK:
3809 case F_SETLKW:
3810 case F_OFD_GETLK:
3811 case F_OFD_SETLK:
3812 case F_OFD_SETLKW:
3813#if BITS_PER_LONG == 32
3814 case F_GETLK64:
3815 case F_SETLK64:
3816 case F_SETLKW64:
3817#endif
3818 err = file_has_perm(cred, file, FILE__LOCK);
3819 break;
3820 }
3821
3822 return err;
3823}
3824
3825static void selinux_file_set_fowner(struct file *file)
3826{
3827 struct file_security_struct *fsec;
3828
3829 fsec = file->f_security;
3830 fsec->fown_sid = current_sid();
3831}
3832
3833static int selinux_file_send_sigiotask(struct task_struct *tsk,
3834 struct fown_struct *fown, int signum)
3835{
3836 struct file *file;
3837 u32 sid = task_sid(tsk);
3838 u32 perm;
3839 struct file_security_struct *fsec;
3840
3841 /* struct fown_struct is never outside the context of a struct file */
3842 file = container_of(fown, struct file, f_owner);
3843
3844 fsec = file->f_security;
3845
3846 if (!signum)
3847 perm = signal_to_av(SIGIO); /* as per send_sigio_to_task */
3848 else
3849 perm = signal_to_av(signum);
3850
3851 return avc_has_perm(&selinux_state,
3852 fsec->fown_sid, sid,
3853 SECCLASS_PROCESS, perm, NULL);
3854}
3855
3856static int selinux_file_receive(struct file *file)
3857{
3858 const struct cred *cred = current_cred();
3859
3860 return file_has_perm(cred, file, file_to_av(file));
3861}
3862
3863static int selinux_file_open(struct file *file, const struct cred *cred)
3864{
3865 struct file_security_struct *fsec;
3866 struct inode_security_struct *isec;
3867
3868 fsec = file->f_security;
3869 isec = inode_security(file_inode(file));
3870 /*
3871 * Save inode label and policy sequence number
3872 * at open-time so that selinux_file_permission
3873 * can determine whether revalidation is necessary.
3874 * Task label is already saved in the file security
3875 * struct as its SID.
3876 */
3877 fsec->isid = isec->sid;
3878 fsec->pseqno = avc_policy_seqno(&selinux_state);
3879 /*
3880 * Since the inode label or policy seqno may have changed
3881 * between the selinux_inode_permission check and the saving
3882 * of state above, recheck that access is still permitted.
3883 * Otherwise, access might never be revalidated against the
3884 * new inode label or new policy.
3885 * This check is not redundant - do not remove.
3886 */
3887 return file_path_has_perm(cred, file, open_file_to_av(file));
3888}
3889
3890/* task security operations */
3891
3892static int selinux_task_alloc(struct task_struct *task,
3893 unsigned long clone_flags)
3894{
3895 u32 sid = current_sid();
3896
3897 return avc_has_perm(&selinux_state,
3898 sid, sid, SECCLASS_PROCESS, PROCESS__FORK, NULL);
3899}
3900
3901/*
3902 * allocate the SELinux part of blank credentials
3903 */
3904static int selinux_cred_alloc_blank(struct cred *cred, gfp_t gfp)
3905{
3906 struct task_security_struct *tsec;
3907
3908 tsec = kzalloc(sizeof(struct task_security_struct), gfp);
3909 if (!tsec)
3910 return -ENOMEM;
3911
3912 cred->security = tsec;
3913 return 0;
3914}
3915
3916/*
3917 * detach and free the LSM part of a set of credentials
3918 */
3919static void selinux_cred_free(struct cred *cred)
3920{
3921 struct task_security_struct *tsec = cred->security;
3922
3923 /*
3924 * cred->security == NULL if security_cred_alloc_blank() or
3925 * security_prepare_creds() returned an error.
3926 */
3927 BUG_ON(cred->security && (unsigned long) cred->security < PAGE_SIZE);
3928 cred->security = (void *) 0x7UL;
3929 kfree(tsec);
3930}
3931
3932/*
3933 * prepare a new set of credentials for modification
3934 */
3935static int selinux_cred_prepare(struct cred *new, const struct cred *old,
3936 gfp_t gfp)
3937{
3938 const struct task_security_struct *old_tsec;
3939 struct task_security_struct *tsec;
3940
3941 old_tsec = old->security;
3942
3943 tsec = kmemdup(old_tsec, sizeof(struct task_security_struct), gfp);
3944 if (!tsec)
3945 return -ENOMEM;
3946
3947 new->security = tsec;
3948 return 0;
3949}
3950
3951/*
3952 * transfer the SELinux data to a blank set of creds
3953 */
3954static void selinux_cred_transfer(struct cred *new, const struct cred *old)
3955{
3956 const struct task_security_struct *old_tsec = old->security;
3957 struct task_security_struct *tsec = new->security;
3958
3959 *tsec = *old_tsec;
3960}
3961
3962static void selinux_cred_getsecid(const struct cred *c, u32 *secid)
3963{
3964 *secid = cred_sid(c);
3965}
3966
3967/*
3968 * set the security data for a kernel service
3969 * - all the creation contexts are set to unlabelled
3970 */
3971static int selinux_kernel_act_as(struct cred *new, u32 secid)
3972{
3973 struct task_security_struct *tsec = new->security;
3974 u32 sid = current_sid();
3975 int ret;
3976
3977 ret = avc_has_perm(&selinux_state,
3978 sid, secid,
3979 SECCLASS_KERNEL_SERVICE,
3980 KERNEL_SERVICE__USE_AS_OVERRIDE,
3981 NULL);
3982 if (ret == 0) {
3983 tsec->sid = secid;
3984 tsec->create_sid = 0;
3985 tsec->keycreate_sid = 0;
3986 tsec->sockcreate_sid = 0;
3987 }
3988 return ret;
3989}
3990
3991/*
3992 * set the file creation context in a security record to the same as the
3993 * objective context of the specified inode
3994 */
3995static int selinux_kernel_create_files_as(struct cred *new, struct inode *inode)
3996{
3997 struct inode_security_struct *isec = inode_security(inode);
3998 struct task_security_struct *tsec = new->security;
3999 u32 sid = current_sid();
4000 int ret;
4001
4002 ret = avc_has_perm(&selinux_state,
4003 sid, isec->sid,
4004 SECCLASS_KERNEL_SERVICE,
4005 KERNEL_SERVICE__CREATE_FILES_AS,
4006 NULL);
4007
4008 if (ret == 0)
4009 tsec->create_sid = isec->sid;
4010 return ret;
4011}
4012
4013static int selinux_kernel_module_request(char *kmod_name)
4014{
4015 struct common_audit_data ad;
4016
4017 ad.type = LSM_AUDIT_DATA_KMOD;
4018 ad.u.kmod_name = kmod_name;
4019
4020 return avc_has_perm(&selinux_state,
4021 current_sid(), SECINITSID_KERNEL, SECCLASS_SYSTEM,
4022 SYSTEM__MODULE_REQUEST, &ad);
4023}
4024
4025static int selinux_kernel_module_from_file(struct file *file)
4026{
4027 struct common_audit_data ad;
4028 struct inode_security_struct *isec;
4029 struct file_security_struct *fsec;
4030 u32 sid = current_sid();
4031 int rc;
4032
4033 /* init_module */
4034 if (file == NULL)
4035 return avc_has_perm(&selinux_state,
4036 sid, sid, SECCLASS_SYSTEM,
4037 SYSTEM__MODULE_LOAD, NULL);
4038
4039 /* finit_module */
4040
4041 ad.type = LSM_AUDIT_DATA_FILE;
4042 ad.u.file = file;
4043
4044 fsec = file->f_security;
4045 if (sid != fsec->sid) {
4046 rc = avc_has_perm(&selinux_state,
4047 sid, fsec->sid, SECCLASS_FD, FD__USE, &ad);
4048 if (rc)
4049 return rc;
4050 }
4051
4052 isec = inode_security(file_inode(file));
4053 return avc_has_perm(&selinux_state,
4054 sid, isec->sid, SECCLASS_SYSTEM,
4055 SYSTEM__MODULE_LOAD, &ad);
4056}
4057
4058static int selinux_kernel_read_file(struct file *file,
4059 enum kernel_read_file_id id)
4060{
4061 int rc = 0;
4062
4063 switch (id) {
4064 case READING_MODULE:
4065 rc = selinux_kernel_module_from_file(file);
4066 break;
4067 default:
4068 break;
4069 }
4070
4071 return rc;
4072}
4073
4074static int selinux_task_setpgid(struct task_struct *p, pid_t pgid)
4075{
4076 return avc_has_perm(&selinux_state,
4077 current_sid(), task_sid(p), SECCLASS_PROCESS,
4078 PROCESS__SETPGID, NULL);
4079}
4080
4081static int selinux_task_getpgid(struct task_struct *p)
4082{
4083 return avc_has_perm(&selinux_state,
4084 current_sid(), task_sid(p), SECCLASS_PROCESS,
4085 PROCESS__GETPGID, NULL);
4086}
4087
4088static int selinux_task_getsid(struct task_struct *p)
4089{
4090 return avc_has_perm(&selinux_state,
4091 current_sid(), task_sid(p), SECCLASS_PROCESS,
4092 PROCESS__GETSESSION, NULL);
4093}
4094
4095static void selinux_task_getsecid(struct task_struct *p, u32 *secid)
4096{
4097 *secid = task_sid(p);
4098}
4099
4100static int selinux_task_setnice(struct task_struct *p, int nice)
4101{
4102 return avc_has_perm(&selinux_state,
4103 current_sid(), task_sid(p), SECCLASS_PROCESS,
4104 PROCESS__SETSCHED, NULL);
4105}
4106
4107static int selinux_task_setioprio(struct task_struct *p, int ioprio)
4108{
4109 return avc_has_perm(&selinux_state,
4110 current_sid(), task_sid(p), SECCLASS_PROCESS,
4111 PROCESS__SETSCHED, NULL);
4112}
4113
4114static int selinux_task_getioprio(struct task_struct *p)
4115{
4116 return avc_has_perm(&selinux_state,
4117 current_sid(), task_sid(p), SECCLASS_PROCESS,
4118 PROCESS__GETSCHED, NULL);
4119}
4120
4121static int selinux_task_prlimit(const struct cred *cred, const struct cred *tcred,
4122 unsigned int flags)
4123{
4124 u32 av = 0;
4125
4126 if (!flags)
4127 return 0;
4128 if (flags & LSM_PRLIMIT_WRITE)
4129 av |= PROCESS__SETRLIMIT;
4130 if (flags & LSM_PRLIMIT_READ)
4131 av |= PROCESS__GETRLIMIT;
4132 return avc_has_perm(&selinux_state,
4133 cred_sid(cred), cred_sid(tcred),
4134 SECCLASS_PROCESS, av, NULL);
4135}
4136
4137static int selinux_task_setrlimit(struct task_struct *p, unsigned int resource,
4138 struct rlimit *new_rlim)
4139{
4140 struct rlimit *old_rlim = p->signal->rlim + resource;
4141
4142 /* Control the ability to change the hard limit (whether
4143 lowering or raising it), so that the hard limit can
4144 later be used as a safe reset point for the soft limit
4145 upon context transitions. See selinux_bprm_committing_creds. */
4146 if (old_rlim->rlim_max != new_rlim->rlim_max)
4147 return avc_has_perm(&selinux_state,
4148 current_sid(), task_sid(p),
4149 SECCLASS_PROCESS, PROCESS__SETRLIMIT, NULL);
4150
4151 return 0;
4152}
4153
4154static int selinux_task_setscheduler(struct task_struct *p)
4155{
4156 return avc_has_perm(&selinux_state,
4157 current_sid(), task_sid(p), SECCLASS_PROCESS,
4158 PROCESS__SETSCHED, NULL);
4159}
4160
4161static int selinux_task_getscheduler(struct task_struct *p)
4162{
4163 return avc_has_perm(&selinux_state,
4164 current_sid(), task_sid(p), SECCLASS_PROCESS,
4165 PROCESS__GETSCHED, NULL);
4166}
4167
4168static int selinux_task_movememory(struct task_struct *p)
4169{
4170 return avc_has_perm(&selinux_state,
4171 current_sid(), task_sid(p), SECCLASS_PROCESS,
4172 PROCESS__SETSCHED, NULL);
4173}
4174
4175static int selinux_task_kill(struct task_struct *p, struct siginfo *info,
4176 int sig, const struct cred *cred)
4177{
4178 u32 secid;
4179 u32 perm;
4180
4181 if (!sig)
4182 perm = PROCESS__SIGNULL; /* null signal; existence test */
4183 else
4184 perm = signal_to_av(sig);
4185 if (!cred)
4186 secid = current_sid();
4187 else
4188 secid = cred_sid(cred);
4189 return avc_has_perm(&selinux_state,
4190 secid, task_sid(p), SECCLASS_PROCESS, perm, NULL);
4191}
4192
4193static void selinux_task_to_inode(struct task_struct *p,
4194 struct inode *inode)
4195{
4196 struct inode_security_struct *isec = inode->i_security;
4197 u32 sid = task_sid(p);
4198
4199 spin_lock(&isec->lock);
4200 isec->sclass = inode_mode_to_security_class(inode->i_mode);
4201 isec->sid = sid;
4202 isec->initialized = LABEL_INITIALIZED;
4203 spin_unlock(&isec->lock);
4204}
4205
4206/* Returns error only if unable to parse addresses */
4207static int selinux_parse_skb_ipv4(struct sk_buff *skb,
4208 struct common_audit_data *ad, u8 *proto)
4209{
4210 int offset, ihlen, ret = -EINVAL;
4211 struct iphdr _iph, *ih;
4212
4213 offset = skb_network_offset(skb);
4214 ih = skb_header_pointer(skb, offset, sizeof(_iph), &_iph);
4215 if (ih == NULL)
4216 goto out;
4217
4218 ihlen = ih->ihl * 4;
4219 if (ihlen < sizeof(_iph))
4220 goto out;
4221
4222 ad->u.net->v4info.saddr = ih->saddr;
4223 ad->u.net->v4info.daddr = ih->daddr;
4224 ret = 0;
4225
4226 if (proto)
4227 *proto = ih->protocol;
4228
4229 switch (ih->protocol) {
4230 case IPPROTO_TCP: {
4231 struct tcphdr _tcph, *th;
4232
4233 if (ntohs(ih->frag_off) & IP_OFFSET)
4234 break;
4235
4236 offset += ihlen;
4237 th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph);
4238 if (th == NULL)
4239 break;
4240
4241 ad->u.net->sport = th->source;
4242 ad->u.net->dport = th->dest;
4243 break;
4244 }
4245
4246 case IPPROTO_UDP: {
4247 struct udphdr _udph, *uh;
4248
4249 if (ntohs(ih->frag_off) & IP_OFFSET)
4250 break;
4251
4252 offset += ihlen;
4253 uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph);
4254 if (uh == NULL)
4255 break;
4256
4257 ad->u.net->sport = uh->source;
4258 ad->u.net->dport = uh->dest;
4259 break;
4260 }
4261
4262 case IPPROTO_DCCP: {
4263 struct dccp_hdr _dccph, *dh;
4264
4265 if (ntohs(ih->frag_off) & IP_OFFSET)
4266 break;
4267
4268 offset += ihlen;
4269 dh = skb_header_pointer(skb, offset, sizeof(_dccph), &_dccph);
4270 if (dh == NULL)
4271 break;
4272
4273 ad->u.net->sport = dh->dccph_sport;
4274 ad->u.net->dport = dh->dccph_dport;
4275 break;
4276 }
4277
4278#if IS_ENABLED(CONFIG_IP_SCTP)
4279 case IPPROTO_SCTP: {
4280 struct sctphdr _sctph, *sh;
4281
4282 if (ntohs(ih->frag_off) & IP_OFFSET)
4283 break;
4284
4285 offset += ihlen;
4286 sh = skb_header_pointer(skb, offset, sizeof(_sctph), &_sctph);
4287 if (sh == NULL)
4288 break;
4289
4290 ad->u.net->sport = sh->source;
4291 ad->u.net->dport = sh->dest;
4292 break;
4293 }
4294#endif
4295 default:
4296 break;
4297 }
4298out:
4299 return ret;
4300}
4301
4302#if IS_ENABLED(CONFIG_IPV6)
4303
4304/* Returns error only if unable to parse addresses */
4305static int selinux_parse_skb_ipv6(struct sk_buff *skb,
4306 struct common_audit_data *ad, u8 *proto)
4307{
4308 u8 nexthdr;
4309 int ret = -EINVAL, offset;
4310 struct ipv6hdr _ipv6h, *ip6;
4311 __be16 frag_off;
4312
4313 offset = skb_network_offset(skb);
4314 ip6 = skb_header_pointer(skb, offset, sizeof(_ipv6h), &_ipv6h);
4315 if (ip6 == NULL)
4316 goto out;
4317
4318 ad->u.net->v6info.saddr = ip6->saddr;
4319 ad->u.net->v6info.daddr = ip6->daddr;
4320 ret = 0;
4321
4322 nexthdr = ip6->nexthdr;
4323 offset += sizeof(_ipv6h);
4324 offset = ipv6_skip_exthdr(skb, offset, &nexthdr, &frag_off);
4325 if (offset < 0)
4326 goto out;
4327
4328 if (proto)
4329 *proto = nexthdr;
4330
4331 switch (nexthdr) {
4332 case IPPROTO_TCP: {
4333 struct tcphdr _tcph, *th;
4334
4335 th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph);
4336 if (th == NULL)
4337 break;
4338
4339 ad->u.net->sport = th->source;
4340 ad->u.net->dport = th->dest;
4341 break;
4342 }
4343
4344 case IPPROTO_UDP: {
4345 struct udphdr _udph, *uh;
4346
4347 uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph);
4348 if (uh == NULL)
4349 break;
4350
4351 ad->u.net->sport = uh->source;
4352 ad->u.net->dport = uh->dest;
4353 break;
4354 }
4355
4356 case IPPROTO_DCCP: {
4357 struct dccp_hdr _dccph, *dh;
4358
4359 dh = skb_header_pointer(skb, offset, sizeof(_dccph), &_dccph);
4360 if (dh == NULL)
4361 break;
4362
4363 ad->u.net->sport = dh->dccph_sport;
4364 ad->u.net->dport = dh->dccph_dport;
4365 break;
4366 }
4367
4368#if IS_ENABLED(CONFIG_IP_SCTP)
4369 case IPPROTO_SCTP: {
4370 struct sctphdr _sctph, *sh;
4371
4372 sh = skb_header_pointer(skb, offset, sizeof(_sctph), &_sctph);
4373 if (sh == NULL)
4374 break;
4375
4376 ad->u.net->sport = sh->source;
4377 ad->u.net->dport = sh->dest;
4378 break;
4379 }
4380#endif
4381 /* includes fragments */
4382 default:
4383 break;
4384 }
4385out:
4386 return ret;
4387}
4388
4389#endif /* IPV6 */
4390
4391static int selinux_parse_skb(struct sk_buff *skb, struct common_audit_data *ad,
4392 char **_addrp, int src, u8 *proto)
4393{
4394 char *addrp;
4395 int ret;
4396
4397 switch (ad->u.net->family) {
4398 case PF_INET:
4399 ret = selinux_parse_skb_ipv4(skb, ad, proto);
4400 if (ret)
4401 goto parse_error;
4402 addrp = (char *)(src ? &ad->u.net->v4info.saddr :
4403 &ad->u.net->v4info.daddr);
4404 goto okay;
4405
4406#if IS_ENABLED(CONFIG_IPV6)
4407 case PF_INET6:
4408 ret = selinux_parse_skb_ipv6(skb, ad, proto);
4409 if (ret)
4410 goto parse_error;
4411 addrp = (char *)(src ? &ad->u.net->v6info.saddr :
4412 &ad->u.net->v6info.daddr);
4413 goto okay;
4414#endif /* IPV6 */
4415 default:
4416 addrp = NULL;
4417 goto okay;
4418 }
4419
4420parse_error:
4421 printk(KERN_WARNING
4422 "SELinux: failure in selinux_parse_skb(),"
4423 " unable to parse packet\n");
4424 return ret;
4425
4426okay:
4427 if (_addrp)
4428 *_addrp = addrp;
4429 return 0;
4430}
4431
4432/**
4433 * selinux_skb_peerlbl_sid - Determine the peer label of a packet
4434 * @skb: the packet
4435 * @family: protocol family
4436 * @sid: the packet's peer label SID
4437 *
4438 * Description:
4439 * Check the various different forms of network peer labeling and determine
4440 * the peer label/SID for the packet; most of the magic actually occurs in
4441 * the security server function security_net_peersid_cmp(). The function
4442 * returns zero if the value in @sid is valid (although it may be SECSID_NULL)
4443 * or -EACCES if @sid is invalid due to inconsistencies with the different
4444 * peer labels.
4445 *
4446 */
4447static int selinux_skb_peerlbl_sid(struct sk_buff *skb, u16 family, u32 *sid)
4448{
4449 int err;
4450 u32 xfrm_sid;
4451 u32 nlbl_sid;
4452 u32 nlbl_type;
4453
4454 err = selinux_xfrm_skb_sid(skb, &xfrm_sid);
4455 if (unlikely(err))
4456 return -EACCES;
4457 err = selinux_netlbl_skbuff_getsid(skb, family, &nlbl_type, &nlbl_sid);
4458 if (unlikely(err))
4459 return -EACCES;
4460
4461 err = security_net_peersid_resolve(&selinux_state, nlbl_sid,
4462 nlbl_type, xfrm_sid, sid);
4463 if (unlikely(err)) {
4464 printk(KERN_WARNING
4465 "SELinux: failure in selinux_skb_peerlbl_sid(),"
4466 " unable to determine packet's peer label\n");
4467 return -EACCES;
4468 }
4469
4470 return 0;
4471}
4472
4473/**
4474 * selinux_conn_sid - Determine the child socket label for a connection
4475 * @sk_sid: the parent socket's SID
4476 * @skb_sid: the packet's SID
4477 * @conn_sid: the resulting connection SID
4478 *
4479 * If @skb_sid is valid then the user:role:type information from @sk_sid is
4480 * combined with the MLS information from @skb_sid in order to create
4481 * @conn_sid. If @skb_sid is not valid then then @conn_sid is simply a copy
4482 * of @sk_sid. Returns zero on success, negative values on failure.
4483 *
4484 */
4485static int selinux_conn_sid(u32 sk_sid, u32 skb_sid, u32 *conn_sid)
4486{
4487 int err = 0;
4488
4489 if (skb_sid != SECSID_NULL)
4490 err = security_sid_mls_copy(&selinux_state, sk_sid, skb_sid,
4491 conn_sid);
4492 else
4493 *conn_sid = sk_sid;
4494
4495 return err;
4496}
4497
4498/* socket security operations */
4499
4500static int socket_sockcreate_sid(const struct task_security_struct *tsec,
4501 u16 secclass, u32 *socksid)
4502{
4503 if (tsec->sockcreate_sid > SECSID_NULL) {
4504 *socksid = tsec->sockcreate_sid;
4505 return 0;
4506 }
4507
4508 return security_transition_sid(&selinux_state, tsec->sid, tsec->sid,
4509 secclass, NULL, socksid);
4510}
4511
4512static int sock_has_perm(struct sock *sk, u32 perms)
4513{
4514 struct sk_security_struct *sksec = sk->sk_security;
4515 struct common_audit_data ad;
4516 struct lsm_network_audit net = {0,};
4517
4518 if (sksec->sid == SECINITSID_KERNEL)
4519 return 0;
4520
4521 ad.type = LSM_AUDIT_DATA_NET;
4522 ad.u.net = &net;
4523 ad.u.net->sk = sk;
4524
4525 return avc_has_perm(&selinux_state,
4526 current_sid(), sksec->sid, sksec->sclass, perms,
4527 &ad);
4528}
4529
4530static int selinux_socket_create(int family, int type,
4531 int protocol, int kern)
4532{
4533 const struct task_security_struct *tsec = current_security();
4534 u32 newsid;
4535 u16 secclass;
4536 int rc;
4537
4538 if (kern)
4539 return 0;
4540
4541 secclass = socket_type_to_security_class(family, type, protocol);
4542 rc = socket_sockcreate_sid(tsec, secclass, &newsid);
4543 if (rc)
4544 return rc;
4545
4546 return avc_has_perm(&selinux_state,
4547 tsec->sid, newsid, secclass, SOCKET__CREATE, NULL);
4548}
4549
4550static int selinux_socket_post_create(struct socket *sock, int family,
4551 int type, int protocol, int kern)
4552{
4553 const struct task_security_struct *tsec = current_security();
4554 struct inode_security_struct *isec = inode_security_novalidate(SOCK_INODE(sock));
4555 struct sk_security_struct *sksec;
4556 u16 sclass = socket_type_to_security_class(family, type, protocol);
4557 u32 sid = SECINITSID_KERNEL;
4558 int err = 0;
4559
4560 if (!kern) {
4561 err = socket_sockcreate_sid(tsec, sclass, &sid);
4562 if (err)
4563 return err;
4564 }
4565
4566 isec->sclass = sclass;
4567 isec->sid = sid;
4568 isec->initialized = LABEL_INITIALIZED;
4569
4570 if (sock->sk) {
4571 sksec = sock->sk->sk_security;
4572 sksec->sclass = sclass;
4573 sksec->sid = sid;
4574 /* Allows detection of the first association on this socket */
4575 if (sksec->sclass == SECCLASS_SCTP_SOCKET)
4576 sksec->sctp_assoc_state = SCTP_ASSOC_UNSET;
4577
4578 err = selinux_netlbl_socket_post_create(sock->sk, family);
4579 }
4580
4581 return err;
4582}
4583
4584/* Range of port numbers used to automatically bind.
4585 Need to determine whether we should perform a name_bind
4586 permission check between the socket and the port number. */
4587
4588static int selinux_socket_bind(struct socket *sock, struct sockaddr *address, int addrlen)
4589{
4590 struct sock *sk = sock->sk;
4591 struct sk_security_struct *sksec = sk->sk_security;
4592 u16 family;
4593 int err;
4594
4595 err = sock_has_perm(sk, SOCKET__BIND);
4596 if (err)
4597 goto out;
4598
4599 /* If PF_INET or PF_INET6, check name_bind permission for the port. */
4600 family = sk->sk_family;
4601 if (family == PF_INET || family == PF_INET6) {
4602 char *addrp;
4603 struct common_audit_data ad;
4604 struct lsm_network_audit net = {0,};
4605 struct sockaddr_in *addr4 = NULL;
4606 struct sockaddr_in6 *addr6 = NULL;
4607 u16 family_sa = address->sa_family;
4608 unsigned short snum;
4609 u32 sid, node_perm;
4610
4611 /*
4612 * sctp_bindx(3) calls via selinux_sctp_bind_connect()
4613 * that validates multiple binding addresses. Because of this
4614 * need to check address->sa_family as it is possible to have
4615 * sk->sk_family = PF_INET6 with addr->sa_family = AF_INET.
4616 */
4617 switch (family_sa) {
4618 case AF_UNSPEC:
4619 case AF_INET:
4620 if (addrlen < sizeof(struct sockaddr_in))
4621 return -EINVAL;
4622 addr4 = (struct sockaddr_in *)address;
4623 if (family_sa == AF_UNSPEC) {
4624 /* see __inet_bind(), we only want to allow
4625 * AF_UNSPEC if the address is INADDR_ANY
4626 */
4627 if (addr4->sin_addr.s_addr != htonl(INADDR_ANY))
4628 goto err_af;
4629 family_sa = AF_INET;
4630 }
4631 snum = ntohs(addr4->sin_port);
4632 addrp = (char *)&addr4->sin_addr.s_addr;
4633 break;
4634 case AF_INET6:
4635 if (addrlen < SIN6_LEN_RFC2133)
4636 return -EINVAL;
4637 addr6 = (struct sockaddr_in6 *)address;
4638 snum = ntohs(addr6->sin6_port);
4639 addrp = (char *)&addr6->sin6_addr.s6_addr;
4640 break;
4641 default:
4642 goto err_af;
4643 }
4644
4645 ad.type = LSM_AUDIT_DATA_NET;
4646 ad.u.net = &net;
4647 ad.u.net->sport = htons(snum);
4648 ad.u.net->family = family_sa;
4649
4650 if (snum) {
4651 int low, high;
4652
4653 inet_get_local_port_range(sock_net(sk), &low, &high);
4654
4655 if (snum < max(inet_prot_sock(sock_net(sk)), low) ||
4656 snum > high) {
4657 err = sel_netport_sid(sk->sk_protocol,
4658 snum, &sid);
4659 if (err)
4660 goto out;
4661 err = avc_has_perm(&selinux_state,
4662 sksec->sid, sid,
4663 sksec->sclass,
4664 SOCKET__NAME_BIND, &ad);
4665 if (err)
4666 goto out;
4667 }
4668 }
4669
4670 switch (sksec->sclass) {
4671 case SECCLASS_TCP_SOCKET:
4672 node_perm = TCP_SOCKET__NODE_BIND;
4673 break;
4674
4675 case SECCLASS_UDP_SOCKET:
4676 node_perm = UDP_SOCKET__NODE_BIND;
4677 break;
4678
4679 case SECCLASS_DCCP_SOCKET:
4680 node_perm = DCCP_SOCKET__NODE_BIND;
4681 break;
4682
4683 case SECCLASS_SCTP_SOCKET:
4684 node_perm = SCTP_SOCKET__NODE_BIND;
4685 break;
4686
4687 default:
4688 node_perm = RAWIP_SOCKET__NODE_BIND;
4689 break;
4690 }
4691
4692 err = sel_netnode_sid(addrp, family_sa, &sid);
4693 if (err)
4694 goto out;
4695
4696 if (family_sa == AF_INET)
4697 ad.u.net->v4info.saddr = addr4->sin_addr.s_addr;
4698 else
4699 ad.u.net->v6info.saddr = addr6->sin6_addr;
4700
4701 err = avc_has_perm(&selinux_state,
4702 sksec->sid, sid,
4703 sksec->sclass, node_perm, &ad);
4704 if (err)
4705 goto out;
4706 }
4707out:
4708 return err;
4709err_af:
4710 /* Note that SCTP services expect -EINVAL, others -EAFNOSUPPORT. */
4711 if (sksec->sclass == SECCLASS_SCTP_SOCKET)
4712 return -EINVAL;
4713 return -EAFNOSUPPORT;
4714}
4715
4716/* This supports connect(2) and SCTP connect services such as sctp_connectx(3)
4717 * and sctp_sendmsg(3) as described in Documentation/security/LSM-sctp.txt
4718 */
4719static int selinux_socket_connect_helper(struct socket *sock,
4720 struct sockaddr *address, int addrlen)
4721{
4722 struct sock *sk = sock->sk;
4723 struct sk_security_struct *sksec = sk->sk_security;
4724 int err;
4725
4726 err = sock_has_perm(sk, SOCKET__CONNECT);
4727 if (err)
4728 return err;
4729
4730 /*
4731 * If a TCP, DCCP or SCTP socket, check name_connect permission
4732 * for the port.
4733 */
4734 if (sksec->sclass == SECCLASS_TCP_SOCKET ||
4735 sksec->sclass == SECCLASS_DCCP_SOCKET ||
4736 sksec->sclass == SECCLASS_SCTP_SOCKET) {
4737 struct common_audit_data ad;
4738 struct lsm_network_audit net = {0,};
4739 struct sockaddr_in *addr4 = NULL;
4740 struct sockaddr_in6 *addr6 = NULL;
4741 unsigned short snum;
4742 u32 sid, perm;
4743
4744 /* sctp_connectx(3) calls via selinux_sctp_bind_connect()
4745 * that validates multiple connect addresses. Because of this
4746 * need to check address->sa_family as it is possible to have
4747 * sk->sk_family = PF_INET6 with addr->sa_family = AF_INET.
4748 */
4749 switch (address->sa_family) {
4750 case AF_INET:
4751 addr4 = (struct sockaddr_in *)address;
4752 if (addrlen < sizeof(struct sockaddr_in))
4753 return -EINVAL;
4754 snum = ntohs(addr4->sin_port);
4755 break;
4756 case AF_INET6:
4757 addr6 = (struct sockaddr_in6 *)address;
4758 if (addrlen < SIN6_LEN_RFC2133)
4759 return -EINVAL;
4760 snum = ntohs(addr6->sin6_port);
4761 break;
4762 default:
4763 /* Note that SCTP services expect -EINVAL, whereas
4764 * others expect -EAFNOSUPPORT.
4765 */
4766 if (sksec->sclass == SECCLASS_SCTP_SOCKET)
4767 return -EINVAL;
4768 else
4769 return -EAFNOSUPPORT;
4770 }
4771
4772 err = sel_netport_sid(sk->sk_protocol, snum, &sid);
4773 if (err)
4774 return err;
4775
4776 switch (sksec->sclass) {
4777 case SECCLASS_TCP_SOCKET:
4778 perm = TCP_SOCKET__NAME_CONNECT;
4779 break;
4780 case SECCLASS_DCCP_SOCKET:
4781 perm = DCCP_SOCKET__NAME_CONNECT;
4782 break;
4783 case SECCLASS_SCTP_SOCKET:
4784 perm = SCTP_SOCKET__NAME_CONNECT;
4785 break;
4786 }
4787
4788 ad.type = LSM_AUDIT_DATA_NET;
4789 ad.u.net = &net;
4790 ad.u.net->dport = htons(snum);
4791 ad.u.net->family = address->sa_family;
4792 err = avc_has_perm(&selinux_state,
4793 sksec->sid, sid, sksec->sclass, perm, &ad);
4794 if (err)
4795 return err;
4796 }
4797
4798 return 0;
4799}
4800
4801/* Supports connect(2), see comments in selinux_socket_connect_helper() */
4802static int selinux_socket_connect(struct socket *sock,
4803 struct sockaddr *address, int addrlen)
4804{
4805 int err;
4806 struct sock *sk = sock->sk;
4807
4808 err = selinux_socket_connect_helper(sock, address, addrlen);
4809 if (err)
4810 return err;
4811
4812 return selinux_netlbl_socket_connect(sk, address);
4813}
4814
4815static int selinux_socket_listen(struct socket *sock, int backlog)
4816{
4817 return sock_has_perm(sock->sk, SOCKET__LISTEN);
4818}
4819
4820static int selinux_socket_accept(struct socket *sock, struct socket *newsock)
4821{
4822 int err;
4823 struct inode_security_struct *isec;
4824 struct inode_security_struct *newisec;
4825 u16 sclass;
4826 u32 sid;
4827
4828 err = sock_has_perm(sock->sk, SOCKET__ACCEPT);
4829 if (err)
4830 return err;
4831
4832 isec = inode_security_novalidate(SOCK_INODE(sock));
4833 spin_lock(&isec->lock);
4834 sclass = isec->sclass;
4835 sid = isec->sid;
4836 spin_unlock(&isec->lock);
4837
4838 newisec = inode_security_novalidate(SOCK_INODE(newsock));
4839 newisec->sclass = sclass;
4840 newisec->sid = sid;
4841 newisec->initialized = LABEL_INITIALIZED;
4842
4843 return 0;
4844}
4845
4846static int selinux_socket_sendmsg(struct socket *sock, struct msghdr *msg,
4847 int size)
4848{
4849 return sock_has_perm(sock->sk, SOCKET__WRITE);
4850}
4851
4852static int selinux_socket_recvmsg(struct socket *sock, struct msghdr *msg,
4853 int size, int flags)
4854{
4855 return sock_has_perm(sock->sk, SOCKET__READ);
4856}
4857
4858static int selinux_socket_getsockname(struct socket *sock)
4859{
4860 return sock_has_perm(sock->sk, SOCKET__GETATTR);
4861}
4862
4863static int selinux_socket_getpeername(struct socket *sock)
4864{
4865 return sock_has_perm(sock->sk, SOCKET__GETATTR);
4866}
4867
4868static int selinux_socket_setsockopt(struct socket *sock, int level, int optname)
4869{
4870 int err;
4871
4872 err = sock_has_perm(sock->sk, SOCKET__SETOPT);
4873 if (err)
4874 return err;
4875
4876 return selinux_netlbl_socket_setsockopt(sock, level, optname);
4877}
4878
4879static int selinux_socket_getsockopt(struct socket *sock, int level,
4880 int optname)
4881{
4882 return sock_has_perm(sock->sk, SOCKET__GETOPT);
4883}
4884
4885static int selinux_socket_shutdown(struct socket *sock, int how)
4886{
4887 return sock_has_perm(sock->sk, SOCKET__SHUTDOWN);
4888}
4889
4890static int selinux_socket_unix_stream_connect(struct sock *sock,
4891 struct sock *other,
4892 struct sock *newsk)
4893{
4894 struct sk_security_struct *sksec_sock = sock->sk_security;
4895 struct sk_security_struct *sksec_other = other->sk_security;
4896 struct sk_security_struct *sksec_new = newsk->sk_security;
4897 struct common_audit_data ad;
4898 struct lsm_network_audit net = {0,};
4899 int err;
4900
4901 ad.type = LSM_AUDIT_DATA_NET;
4902 ad.u.net = &net;
4903 ad.u.net->sk = other;
4904
4905 err = avc_has_perm(&selinux_state,
4906 sksec_sock->sid, sksec_other->sid,
4907 sksec_other->sclass,
4908 UNIX_STREAM_SOCKET__CONNECTTO, &ad);
4909 if (err)
4910 return err;
4911
4912 /* server child socket */
4913 sksec_new->peer_sid = sksec_sock->sid;
4914 err = security_sid_mls_copy(&selinux_state, sksec_other->sid,
4915 sksec_sock->sid, &sksec_new->sid);
4916 if (err)
4917 return err;
4918
4919 /* connecting socket */
4920 sksec_sock->peer_sid = sksec_new->sid;
4921
4922 return 0;
4923}
4924
4925static int selinux_socket_unix_may_send(struct socket *sock,
4926 struct socket *other)
4927{
4928 struct sk_security_struct *ssec = sock->sk->sk_security;
4929 struct sk_security_struct *osec = other->sk->sk_security;
4930 struct common_audit_data ad;
4931 struct lsm_network_audit net = {0,};
4932
4933 ad.type = LSM_AUDIT_DATA_NET;
4934 ad.u.net = &net;
4935 ad.u.net->sk = other->sk;
4936
4937 return avc_has_perm(&selinux_state,
4938 ssec->sid, osec->sid, osec->sclass, SOCKET__SENDTO,
4939 &ad);
4940}
4941
4942static int selinux_inet_sys_rcv_skb(struct net *ns, int ifindex,
4943 char *addrp, u16 family, u32 peer_sid,
4944 struct common_audit_data *ad)
4945{
4946 int err;
4947 u32 if_sid;
4948 u32 node_sid;
4949
4950 err = sel_netif_sid(ns, ifindex, &if_sid);
4951 if (err)
4952 return err;
4953 err = avc_has_perm(&selinux_state,
4954 peer_sid, if_sid,
4955 SECCLASS_NETIF, NETIF__INGRESS, ad);
4956 if (err)
4957 return err;
4958
4959 err = sel_netnode_sid(addrp, family, &node_sid);
4960 if (err)
4961 return err;
4962 return avc_has_perm(&selinux_state,
4963 peer_sid, node_sid,
4964 SECCLASS_NODE, NODE__RECVFROM, ad);
4965}
4966
4967static int selinux_sock_rcv_skb_compat(struct sock *sk, struct sk_buff *skb,
4968 u16 family)
4969{
4970 int err = 0;
4971 struct sk_security_struct *sksec = sk->sk_security;
4972 u32 sk_sid = sksec->sid;
4973 struct common_audit_data ad;
4974 struct lsm_network_audit net = {0,};
4975 char *addrp;
4976
4977 ad.type = LSM_AUDIT_DATA_NET;
4978 ad.u.net = &net;
4979 ad.u.net->netif = skb->skb_iif;
4980 ad.u.net->family = family;
4981 err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL);
4982 if (err)
4983 return err;
4984
4985 if (selinux_secmark_enabled()) {
4986 err = avc_has_perm(&selinux_state,
4987 sk_sid, skb->secmark, SECCLASS_PACKET,
4988 PACKET__RECV, &ad);
4989 if (err)
4990 return err;
4991 }
4992
4993 err = selinux_netlbl_sock_rcv_skb(sksec, skb, family, &ad);
4994 if (err)
4995 return err;
4996 err = selinux_xfrm_sock_rcv_skb(sksec->sid, skb, &ad);
4997
4998 return err;
4999}
5000
5001static int selinux_socket_sock_rcv_skb(struct sock *sk, struct sk_buff *skb)
5002{
5003 int err;
5004 struct sk_security_struct *sksec = sk->sk_security;
5005 u16 family = sk->sk_family;
5006 u32 sk_sid = sksec->sid;
5007 struct common_audit_data ad;
5008 struct lsm_network_audit net = {0,};
5009 char *addrp;
5010 u8 secmark_active;
5011 u8 peerlbl_active;
5012
5013 if (family != PF_INET && family != PF_INET6)
5014 return 0;
5015
5016 /* Handle mapped IPv4 packets arriving via IPv6 sockets */
5017 if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
5018 family = PF_INET;
5019
5020 /* If any sort of compatibility mode is enabled then handoff processing
5021 * to the selinux_sock_rcv_skb_compat() function to deal with the
5022 * special handling. We do this in an attempt to keep this function
5023 * as fast and as clean as possible. */
5024 if (!selinux_policycap_netpeer())
5025 return selinux_sock_rcv_skb_compat(sk, skb, family);
5026
5027 secmark_active = selinux_secmark_enabled();
5028 peerlbl_active = selinux_peerlbl_enabled();
5029 if (!secmark_active && !peerlbl_active)
5030 return 0;
5031
5032 ad.type = LSM_AUDIT_DATA_NET;
5033 ad.u.net = &net;
5034 ad.u.net->netif = skb->skb_iif;
5035 ad.u.net->family = family;
5036 err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL);
5037 if (err)
5038 return err;
5039
5040 if (peerlbl_active) {
5041 u32 peer_sid;
5042
5043 err = selinux_skb_peerlbl_sid(skb, family, &peer_sid);
5044 if (err)
5045 return err;
5046 err = selinux_inet_sys_rcv_skb(sock_net(sk), skb->skb_iif,
5047 addrp, family, peer_sid, &ad);
5048 if (err) {
5049 selinux_netlbl_err(skb, family, err, 0);
5050 return err;
5051 }
5052 err = avc_has_perm(&selinux_state,
5053 sk_sid, peer_sid, SECCLASS_PEER,
5054 PEER__RECV, &ad);
5055 if (err) {
5056 selinux_netlbl_err(skb, family, err, 0);
5057 return err;
5058 }
5059 }
5060
5061 if (secmark_active) {
5062 err = avc_has_perm(&selinux_state,
5063 sk_sid, skb->secmark, SECCLASS_PACKET,
5064 PACKET__RECV, &ad);
5065 if (err)
5066 return err;
5067 }
5068
5069 return err;
5070}
5071
5072static int selinux_socket_getpeersec_stream(struct socket *sock, char __user *optval,
5073 int __user *optlen, unsigned len)
5074{
5075 int err = 0;
5076 char *scontext;
5077 u32 scontext_len;
5078 struct sk_security_struct *sksec = sock->sk->sk_security;
5079 u32 peer_sid = SECSID_NULL;
5080
5081 if (sksec->sclass == SECCLASS_UNIX_STREAM_SOCKET ||
5082 sksec->sclass == SECCLASS_TCP_SOCKET ||
5083 sksec->sclass == SECCLASS_SCTP_SOCKET)
5084 peer_sid = sksec->peer_sid;
5085 if (peer_sid == SECSID_NULL)
5086 return -ENOPROTOOPT;
5087
5088 err = security_sid_to_context(&selinux_state, peer_sid, &scontext,
5089 &scontext_len);
5090 if (err)
5091 return err;
5092
5093 if (scontext_len > len) {
5094 err = -ERANGE;
5095 goto out_len;
5096 }
5097
5098 if (copy_to_user(optval, scontext, scontext_len))
5099 err = -EFAULT;
5100
5101out_len:
5102 if (put_user(scontext_len, optlen))
5103 err = -EFAULT;
5104 kfree(scontext);
5105 return err;
5106}
5107
5108static int selinux_socket_getpeersec_dgram(struct socket *sock, struct sk_buff *skb, u32 *secid)
5109{
5110 u32 peer_secid = SECSID_NULL;
5111 u16 family;
5112 struct inode_security_struct *isec;
5113
5114 if (skb && skb->protocol == htons(ETH_P_IP))
5115 family = PF_INET;
5116 else if (skb && skb->protocol == htons(ETH_P_IPV6))
5117 family = PF_INET6;
5118 else if (sock)
5119 family = sock->sk->sk_family;
5120 else
5121 goto out;
5122
5123 if (sock && family == PF_UNIX) {
5124 isec = inode_security_novalidate(SOCK_INODE(sock));
5125 peer_secid = isec->sid;
5126 } else if (skb)
5127 selinux_skb_peerlbl_sid(skb, family, &peer_secid);
5128
5129out:
5130 *secid = peer_secid;
5131 if (peer_secid == SECSID_NULL)
5132 return -EINVAL;
5133 return 0;
5134}
5135
5136static int selinux_sk_alloc_security(struct sock *sk, int family, gfp_t priority)
5137{
5138 struct sk_security_struct *sksec;
5139
5140 sksec = kzalloc(sizeof(*sksec), priority);
5141 if (!sksec)
5142 return -ENOMEM;
5143
5144 sksec->peer_sid = SECINITSID_UNLABELED;
5145 sksec->sid = SECINITSID_UNLABELED;
5146 sksec->sclass = SECCLASS_SOCKET;
5147 selinux_netlbl_sk_security_reset(sksec);
5148 sk->sk_security = sksec;
5149
5150 return 0;
5151}
5152
5153static void selinux_sk_free_security(struct sock *sk)
5154{
5155 struct sk_security_struct *sksec = sk->sk_security;
5156
5157 sk->sk_security = NULL;
5158 selinux_netlbl_sk_security_free(sksec);
5159 kfree(sksec);
5160}
5161
5162static void selinux_sk_clone_security(const struct sock *sk, struct sock *newsk)
5163{
5164 struct sk_security_struct *sksec = sk->sk_security;
5165 struct sk_security_struct *newsksec = newsk->sk_security;
5166
5167 newsksec->sid = sksec->sid;
5168 newsksec->peer_sid = sksec->peer_sid;
5169 newsksec->sclass = sksec->sclass;
5170
5171 selinux_netlbl_sk_security_reset(newsksec);
5172}
5173
5174static void selinux_sk_getsecid(struct sock *sk, u32 *secid)
5175{
5176 if (!sk)
5177 *secid = SECINITSID_ANY_SOCKET;
5178 else {
5179 struct sk_security_struct *sksec = sk->sk_security;
5180
5181 *secid = sksec->sid;
5182 }
5183}
5184
5185static void selinux_sock_graft(struct sock *sk, struct socket *parent)
5186{
5187 struct inode_security_struct *isec =
5188 inode_security_novalidate(SOCK_INODE(parent));
5189 struct sk_security_struct *sksec = sk->sk_security;
5190
5191 if (sk->sk_family == PF_INET || sk->sk_family == PF_INET6 ||
5192 sk->sk_family == PF_UNIX)
5193 isec->sid = sksec->sid;
5194 sksec->sclass = isec->sclass;
5195}
5196
5197/* Called whenever SCTP receives an INIT chunk. This happens when an incoming
5198 * connect(2), sctp_connectx(3) or sctp_sendmsg(3) (with no association
5199 * already present).
5200 */
5201static int selinux_sctp_assoc_request(struct sctp_endpoint *ep,
5202 struct sk_buff *skb)
5203{
5204 struct sk_security_struct *sksec = ep->base.sk->sk_security;
5205 struct common_audit_data ad;
5206 struct lsm_network_audit net = {0,};
5207 u8 peerlbl_active;
5208 u32 peer_sid = SECINITSID_UNLABELED;
5209 u32 conn_sid;
5210 int err = 0;
5211
5212 if (!selinux_policycap_extsockclass())
5213 return 0;
5214
5215 peerlbl_active = selinux_peerlbl_enabled();
5216
5217 if (peerlbl_active) {
5218 /* This will return peer_sid = SECSID_NULL if there are
5219 * no peer labels, see security_net_peersid_resolve().
5220 */
5221 err = selinux_skb_peerlbl_sid(skb, ep->base.sk->sk_family,
5222 &peer_sid);
5223 if (err)
5224 return err;
5225
5226 if (peer_sid == SECSID_NULL)
5227 peer_sid = SECINITSID_UNLABELED;
5228 }
5229
5230 if (sksec->sctp_assoc_state == SCTP_ASSOC_UNSET) {
5231 sksec->sctp_assoc_state = SCTP_ASSOC_SET;
5232
5233 /* Here as first association on socket. As the peer SID
5234 * was allowed by peer recv (and the netif/node checks),
5235 * then it is approved by policy and used as the primary
5236 * peer SID for getpeercon(3).
5237 */
5238 sksec->peer_sid = peer_sid;
5239 } else if (sksec->peer_sid != peer_sid) {
5240 /* Other association peer SIDs are checked to enforce
5241 * consistency among the peer SIDs.
5242 */
5243 ad.type = LSM_AUDIT_DATA_NET;
5244 ad.u.net = &net;
5245 ad.u.net->sk = ep->base.sk;
5246 err = avc_has_perm(&selinux_state,
5247 sksec->peer_sid, peer_sid, sksec->sclass,
5248 SCTP_SOCKET__ASSOCIATION, &ad);
5249 if (err)
5250 return err;
5251 }
5252
5253 /* Compute the MLS component for the connection and store
5254 * the information in ep. This will be used by SCTP TCP type
5255 * sockets and peeled off connections as they cause a new
5256 * socket to be generated. selinux_sctp_sk_clone() will then
5257 * plug this into the new socket.
5258 */
5259 err = selinux_conn_sid(sksec->sid, peer_sid, &conn_sid);
5260 if (err)
5261 return err;
5262
5263 ep->secid = conn_sid;
5264 ep->peer_secid = peer_sid;
5265
5266 /* Set any NetLabel labels including CIPSO/CALIPSO options. */
5267 return selinux_netlbl_sctp_assoc_request(ep, skb);
5268}
5269
5270/* Check if sctp IPv4/IPv6 addresses are valid for binding or connecting
5271 * based on their @optname.
5272 */
5273static int selinux_sctp_bind_connect(struct sock *sk, int optname,
5274 struct sockaddr *address,
5275 int addrlen)
5276{
5277 int len, err = 0, walk_size = 0;
5278 void *addr_buf;
5279 struct sockaddr *addr;
5280 struct socket *sock;
5281
5282 if (!selinux_policycap_extsockclass())
5283 return 0;
5284
5285 /* Process one or more addresses that may be IPv4 or IPv6 */
5286 sock = sk->sk_socket;
5287 addr_buf = address;
5288
5289 while (walk_size < addrlen) {
5290 addr = addr_buf;
5291 switch (addr->sa_family) {
5292 case AF_UNSPEC:
5293 case AF_INET:
5294 len = sizeof(struct sockaddr_in);
5295 break;
5296 case AF_INET6:
5297 len = sizeof(struct sockaddr_in6);
5298 break;
5299 default:
5300 return -EINVAL;
5301 }
5302
5303 err = -EINVAL;
5304 switch (optname) {
5305 /* Bind checks */
5306 case SCTP_PRIMARY_ADDR:
5307 case SCTP_SET_PEER_PRIMARY_ADDR:
5308 case SCTP_SOCKOPT_BINDX_ADD:
5309 err = selinux_socket_bind(sock, addr, len);
5310 break;
5311 /* Connect checks */
5312 case SCTP_SOCKOPT_CONNECTX:
5313 case SCTP_PARAM_SET_PRIMARY:
5314 case SCTP_PARAM_ADD_IP:
5315 case SCTP_SENDMSG_CONNECT:
5316 err = selinux_socket_connect_helper(sock, addr, len);
5317 if (err)
5318 return err;
5319
5320 /* As selinux_sctp_bind_connect() is called by the
5321 * SCTP protocol layer, the socket is already locked,
5322 * therefore selinux_netlbl_socket_connect_locked() is
5323 * is called here. The situations handled are:
5324 * sctp_connectx(3), sctp_sendmsg(3), sendmsg(2),
5325 * whenever a new IP address is added or when a new
5326 * primary address is selected.
5327 * Note that an SCTP connect(2) call happens before
5328 * the SCTP protocol layer and is handled via
5329 * selinux_socket_connect().
5330 */
5331 err = selinux_netlbl_socket_connect_locked(sk, addr);
5332 break;
5333 }
5334
5335 if (err)
5336 return err;
5337
5338 addr_buf += len;
5339 walk_size += len;
5340 }
5341
5342 return 0;
5343}
5344
5345/* Called whenever a new socket is created by accept(2) or sctp_peeloff(3). */
5346static void selinux_sctp_sk_clone(struct sctp_endpoint *ep, struct sock *sk,
5347 struct sock *newsk)
5348{
5349 struct sk_security_struct *sksec = sk->sk_security;
5350 struct sk_security_struct *newsksec = newsk->sk_security;
5351
5352 /* If policy does not support SECCLASS_SCTP_SOCKET then call
5353 * the non-sctp clone version.
5354 */
5355 if (!selinux_policycap_extsockclass())
5356 return selinux_sk_clone_security(sk, newsk);
5357
5358 newsksec->sid = ep->secid;
5359 newsksec->peer_sid = ep->peer_secid;
5360 newsksec->sclass = sksec->sclass;
5361 selinux_netlbl_sctp_sk_clone(sk, newsk);
5362}
5363
5364static int selinux_inet_conn_request(struct sock *sk, struct sk_buff *skb,
5365 struct request_sock *req)
5366{
5367 struct sk_security_struct *sksec = sk->sk_security;
5368 int err;
5369 u16 family = req->rsk_ops->family;
5370 u32 connsid;
5371 u32 peersid;
5372
5373 err = selinux_skb_peerlbl_sid(skb, family, &peersid);
5374 if (err)
5375 return err;
5376 err = selinux_conn_sid(sksec->sid, peersid, &connsid);
5377 if (err)
5378 return err;
5379 req->secid = connsid;
5380 req->peer_secid = peersid;
5381
5382 return selinux_netlbl_inet_conn_request(req, family);
5383}
5384
5385static void selinux_inet_csk_clone(struct sock *newsk,
5386 const struct request_sock *req)
5387{
5388 struct sk_security_struct *newsksec = newsk->sk_security;
5389
5390 newsksec->sid = req->secid;
5391 newsksec->peer_sid = req->peer_secid;
5392 /* NOTE: Ideally, we should also get the isec->sid for the
5393 new socket in sync, but we don't have the isec available yet.
5394 So we will wait until sock_graft to do it, by which
5395 time it will have been created and available. */
5396
5397 /* We don't need to take any sort of lock here as we are the only
5398 * thread with access to newsksec */
5399 selinux_netlbl_inet_csk_clone(newsk, req->rsk_ops->family);
5400}
5401
5402static void selinux_inet_conn_established(struct sock *sk, struct sk_buff *skb)
5403{
5404 u16 family = sk->sk_family;
5405 struct sk_security_struct *sksec = sk->sk_security;
5406
5407 /* handle mapped IPv4 packets arriving via IPv6 sockets */
5408 if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
5409 family = PF_INET;
5410
5411 selinux_skb_peerlbl_sid(skb, family, &sksec->peer_sid);
5412}
5413
5414static int selinux_secmark_relabel_packet(u32 sid)
5415{
5416 const struct task_security_struct *__tsec;
5417 u32 tsid;
5418
5419 __tsec = current_security();
5420 tsid = __tsec->sid;
5421
5422 return avc_has_perm(&selinux_state,
5423 tsid, sid, SECCLASS_PACKET, PACKET__RELABELTO,
5424 NULL);
5425}
5426
5427static void selinux_secmark_refcount_inc(void)
5428{
5429 atomic_inc(&selinux_secmark_refcount);
5430}
5431
5432static void selinux_secmark_refcount_dec(void)
5433{
5434 atomic_dec(&selinux_secmark_refcount);
5435}
5436
5437static void selinux_req_classify_flow(const struct request_sock *req,
5438 struct flowi *fl)
5439{
5440 fl->flowi_secid = req->secid;
5441}
5442
5443static int selinux_tun_dev_alloc_security(void **security)
5444{
5445 struct tun_security_struct *tunsec;
5446
5447 tunsec = kzalloc(sizeof(*tunsec), GFP_KERNEL);
5448 if (!tunsec)
5449 return -ENOMEM;
5450 tunsec->sid = current_sid();
5451
5452 *security = tunsec;
5453 return 0;
5454}
5455
5456static void selinux_tun_dev_free_security(void *security)
5457{
5458 kfree(security);
5459}
5460
5461static int selinux_tun_dev_create(void)
5462{
5463 u32 sid = current_sid();
5464
5465 /* we aren't taking into account the "sockcreate" SID since the socket
5466 * that is being created here is not a socket in the traditional sense,
5467 * instead it is a private sock, accessible only to the kernel, and
5468 * representing a wide range of network traffic spanning multiple
5469 * connections unlike traditional sockets - check the TUN driver to
5470 * get a better understanding of why this socket is special */
5471
5472 return avc_has_perm(&selinux_state,
5473 sid, sid, SECCLASS_TUN_SOCKET, TUN_SOCKET__CREATE,
5474 NULL);
5475}
5476
5477static int selinux_tun_dev_attach_queue(void *security)
5478{
5479 struct tun_security_struct *tunsec = security;
5480
5481 return avc_has_perm(&selinux_state,
5482 current_sid(), tunsec->sid, SECCLASS_TUN_SOCKET,
5483 TUN_SOCKET__ATTACH_QUEUE, NULL);
5484}
5485
5486static int selinux_tun_dev_attach(struct sock *sk, void *security)
5487{
5488 struct tun_security_struct *tunsec = security;
5489 struct sk_security_struct *sksec = sk->sk_security;
5490
5491 /* we don't currently perform any NetLabel based labeling here and it
5492 * isn't clear that we would want to do so anyway; while we could apply
5493 * labeling without the support of the TUN user the resulting labeled
5494 * traffic from the other end of the connection would almost certainly
5495 * cause confusion to the TUN user that had no idea network labeling
5496 * protocols were being used */
5497
5498 sksec->sid = tunsec->sid;
5499 sksec->sclass = SECCLASS_TUN_SOCKET;
5500
5501 return 0;
5502}
5503
5504static int selinux_tun_dev_open(void *security)
5505{
5506 struct tun_security_struct *tunsec = security;
5507 u32 sid = current_sid();
5508 int err;
5509
5510 err = avc_has_perm(&selinux_state,
5511 sid, tunsec->sid, SECCLASS_TUN_SOCKET,
5512 TUN_SOCKET__RELABELFROM, NULL);
5513 if (err)
5514 return err;
5515 err = avc_has_perm(&selinux_state,
5516 sid, sid, SECCLASS_TUN_SOCKET,
5517 TUN_SOCKET__RELABELTO, NULL);
5518 if (err)
5519 return err;
5520 tunsec->sid = sid;
5521
5522 return 0;
5523}
5524
5525static int selinux_nlmsg_perm(struct sock *sk, struct sk_buff *skb)
5526{
5527 int err = 0;
5528 u32 perm;
5529 struct nlmsghdr *nlh;
5530 struct sk_security_struct *sksec = sk->sk_security;
5531
5532 if (skb->len < NLMSG_HDRLEN) {
5533 err = -EINVAL;
5534 goto out;
5535 }
5536 nlh = nlmsg_hdr(skb);
5537
5538 err = selinux_nlmsg_lookup(sksec->sclass, nlh->nlmsg_type, &perm);
5539 if (err) {
5540 if (err == -EINVAL) {
5541 pr_warn_ratelimited("SELinux: unrecognized netlink"
5542 " message: protocol=%hu nlmsg_type=%hu sclass=%s"
5543 " pig=%d comm=%s\n",
5544 sk->sk_protocol, nlh->nlmsg_type,
5545 secclass_map[sksec->sclass - 1].name,
5546 task_pid_nr(current), current->comm);
5547 if (!enforcing_enabled(&selinux_state) ||
5548 security_get_allow_unknown(&selinux_state))
5549 err = 0;
5550 }
5551
5552 /* Ignore */
5553 if (err == -ENOENT)
5554 err = 0;
5555 goto out;
5556 }
5557
5558 err = sock_has_perm(sk, perm);
5559out:
5560 return err;
5561}
5562
5563#ifdef CONFIG_NETFILTER
5564
5565static unsigned int selinux_ip_forward(struct sk_buff *skb,
5566 const struct net_device *indev,
5567 u16 family)
5568{
5569 int err;
5570 char *addrp;
5571 u32 peer_sid;
5572 struct common_audit_data ad;
5573 struct lsm_network_audit net = {0,};
5574 u8 secmark_active;
5575 u8 netlbl_active;
5576 u8 peerlbl_active;
5577
5578 if (!selinux_policycap_netpeer())
5579 return NF_ACCEPT;
5580
5581 secmark_active = selinux_secmark_enabled();
5582 netlbl_active = netlbl_enabled();
5583 peerlbl_active = selinux_peerlbl_enabled();
5584 if (!secmark_active && !peerlbl_active)
5585 return NF_ACCEPT;
5586
5587 if (selinux_skb_peerlbl_sid(skb, family, &peer_sid) != 0)
5588 return NF_DROP;
5589
5590 ad.type = LSM_AUDIT_DATA_NET;
5591 ad.u.net = &net;
5592 ad.u.net->netif = indev->ifindex;
5593 ad.u.net->family = family;
5594 if (selinux_parse_skb(skb, &ad, &addrp, 1, NULL) != 0)
5595 return NF_DROP;
5596
5597 if (peerlbl_active) {
5598 err = selinux_inet_sys_rcv_skb(dev_net(indev), indev->ifindex,
5599 addrp, family, peer_sid, &ad);
5600 if (err) {
5601 selinux_netlbl_err(skb, family, err, 1);
5602 return NF_DROP;
5603 }
5604 }
5605
5606 if (secmark_active)
5607 if (avc_has_perm(&selinux_state,
5608 peer_sid, skb->secmark,
5609 SECCLASS_PACKET, PACKET__FORWARD_IN, &ad))
5610 return NF_DROP;
5611
5612 if (netlbl_active)
5613 /* we do this in the FORWARD path and not the POST_ROUTING
5614 * path because we want to make sure we apply the necessary
5615 * labeling before IPsec is applied so we can leverage AH
5616 * protection */
5617 if (selinux_netlbl_skbuff_setsid(skb, family, peer_sid) != 0)
5618 return NF_DROP;
5619
5620 return NF_ACCEPT;
5621}
5622
5623static unsigned int selinux_ipv4_forward(void *priv,
5624 struct sk_buff *skb,
5625 const struct nf_hook_state *state)
5626{
5627 return selinux_ip_forward(skb, state->in, PF_INET);
5628}
5629
5630#if IS_ENABLED(CONFIG_IPV6)
5631static unsigned int selinux_ipv6_forward(void *priv,
5632 struct sk_buff *skb,
5633 const struct nf_hook_state *state)
5634{
5635 return selinux_ip_forward(skb, state->in, PF_INET6);
5636}
5637#endif /* IPV6 */
5638
5639static unsigned int selinux_ip_output(struct sk_buff *skb,
5640 u16 family)
5641{
5642 struct sock *sk;
5643 u32 sid;
5644
5645 if (!netlbl_enabled())
5646 return NF_ACCEPT;
5647
5648 /* we do this in the LOCAL_OUT path and not the POST_ROUTING path
5649 * because we want to make sure we apply the necessary labeling
5650 * before IPsec is applied so we can leverage AH protection */
5651 sk = skb->sk;
5652 if (sk) {
5653 struct sk_security_struct *sksec;
5654
5655 if (sk_listener(sk))
5656 /* if the socket is the listening state then this
5657 * packet is a SYN-ACK packet which means it needs to
5658 * be labeled based on the connection/request_sock and
5659 * not the parent socket. unfortunately, we can't
5660 * lookup the request_sock yet as it isn't queued on
5661 * the parent socket until after the SYN-ACK is sent.
5662 * the "solution" is to simply pass the packet as-is
5663 * as any IP option based labeling should be copied
5664 * from the initial connection request (in the IP
5665 * layer). it is far from ideal, but until we get a
5666 * security label in the packet itself this is the
5667 * best we can do. */
5668 return NF_ACCEPT;
5669
5670 /* standard practice, label using the parent socket */
5671 sksec = sk->sk_security;
5672 sid = sksec->sid;
5673 } else
5674 sid = SECINITSID_KERNEL;
5675 if (selinux_netlbl_skbuff_setsid(skb, family, sid) != 0)
5676 return NF_DROP;
5677
5678 return NF_ACCEPT;
5679}
5680
5681static unsigned int selinux_ipv4_output(void *priv,
5682 struct sk_buff *skb,
5683 const struct nf_hook_state *state)
5684{
5685 return selinux_ip_output(skb, PF_INET);
5686}
5687
5688#if IS_ENABLED(CONFIG_IPV6)
5689static unsigned int selinux_ipv6_output(void *priv,
5690 struct sk_buff *skb,
5691 const struct nf_hook_state *state)
5692{
5693 return selinux_ip_output(skb, PF_INET6);
5694}
5695#endif /* IPV6 */
5696
5697static unsigned int selinux_ip_postroute_compat(struct sk_buff *skb,
5698 int ifindex,
5699 u16 family)
5700{
5701 struct sock *sk = skb_to_full_sk(skb);
5702 struct sk_security_struct *sksec;
5703 struct common_audit_data ad;
5704 struct lsm_network_audit net = {0,};
5705 char *addrp;
5706 u8 proto;
5707
5708 if (sk == NULL)
5709 return NF_ACCEPT;
5710 sksec = sk->sk_security;
5711
5712 ad.type = LSM_AUDIT_DATA_NET;
5713 ad.u.net = &net;
5714 ad.u.net->netif = ifindex;
5715 ad.u.net->family = family;
5716 if (selinux_parse_skb(skb, &ad, &addrp, 0, &proto))
5717 return NF_DROP;
5718
5719 if (selinux_secmark_enabled())
5720 if (avc_has_perm(&selinux_state,
5721 sksec->sid, skb->secmark,
5722 SECCLASS_PACKET, PACKET__SEND, &ad))
5723 return NF_DROP_ERR(-ECONNREFUSED);
5724
5725 if (selinux_xfrm_postroute_last(sksec->sid, skb, &ad, proto))
5726 return NF_DROP_ERR(-ECONNREFUSED);
5727
5728 return NF_ACCEPT;
5729}
5730
5731static unsigned int selinux_ip_postroute(struct sk_buff *skb,
5732 const struct net_device *outdev,
5733 u16 family)
5734{
5735 u32 secmark_perm;
5736 u32 peer_sid;
5737 int ifindex = outdev->ifindex;
5738 struct sock *sk;
5739 struct common_audit_data ad;
5740 struct lsm_network_audit net = {0,};
5741 char *addrp;
5742 u8 secmark_active;
5743 u8 peerlbl_active;
5744
5745 /* If any sort of compatibility mode is enabled then handoff processing
5746 * to the selinux_ip_postroute_compat() function to deal with the
5747 * special handling. We do this in an attempt to keep this function
5748 * as fast and as clean as possible. */
5749 if (!selinux_policycap_netpeer())
5750 return selinux_ip_postroute_compat(skb, ifindex, family);
5751
5752 secmark_active = selinux_secmark_enabled();
5753 peerlbl_active = selinux_peerlbl_enabled();
5754 if (!secmark_active && !peerlbl_active)
5755 return NF_ACCEPT;
5756
5757 sk = skb_to_full_sk(skb);
5758
5759#ifdef CONFIG_XFRM
5760 /* If skb->dst->xfrm is non-NULL then the packet is undergoing an IPsec
5761 * packet transformation so allow the packet to pass without any checks
5762 * since we'll have another chance to perform access control checks
5763 * when the packet is on it's final way out.
5764 * NOTE: there appear to be some IPv6 multicast cases where skb->dst
5765 * is NULL, in this case go ahead and apply access control.
5766 * NOTE: if this is a local socket (skb->sk != NULL) that is in the
5767 * TCP listening state we cannot wait until the XFRM processing
5768 * is done as we will miss out on the SA label if we do;
5769 * unfortunately, this means more work, but it is only once per
5770 * connection. */
5771 if (skb_dst(skb) != NULL && skb_dst(skb)->xfrm != NULL &&
5772 !(sk && sk_listener(sk)))
5773 return NF_ACCEPT;
5774#endif
5775
5776 if (sk == NULL) {
5777 /* Without an associated socket the packet is either coming
5778 * from the kernel or it is being forwarded; check the packet
5779 * to determine which and if the packet is being forwarded
5780 * query the packet directly to determine the security label. */
5781 if (skb->skb_iif) {
5782 secmark_perm = PACKET__FORWARD_OUT;
5783 if (selinux_skb_peerlbl_sid(skb, family, &peer_sid))
5784 return NF_DROP;
5785 } else {
5786 secmark_perm = PACKET__SEND;
5787 peer_sid = SECINITSID_KERNEL;
5788 }
5789 } else if (sk_listener(sk)) {
5790 /* Locally generated packet but the associated socket is in the
5791 * listening state which means this is a SYN-ACK packet. In
5792 * this particular case the correct security label is assigned
5793 * to the connection/request_sock but unfortunately we can't
5794 * query the request_sock as it isn't queued on the parent
5795 * socket until after the SYN-ACK packet is sent; the only
5796 * viable choice is to regenerate the label like we do in
5797 * selinux_inet_conn_request(). See also selinux_ip_output()
5798 * for similar problems. */
5799 u32 skb_sid;
5800 struct sk_security_struct *sksec;
5801
5802 sksec = sk->sk_security;
5803 if (selinux_skb_peerlbl_sid(skb, family, &skb_sid))
5804 return NF_DROP;
5805 /* At this point, if the returned skb peerlbl is SECSID_NULL
5806 * and the packet has been through at least one XFRM
5807 * transformation then we must be dealing with the "final"
5808 * form of labeled IPsec packet; since we've already applied
5809 * all of our access controls on this packet we can safely
5810 * pass the packet. */
5811 if (skb_sid == SECSID_NULL) {
5812 switch (family) {
5813 case PF_INET:
5814 if (IPCB(skb)->flags & IPSKB_XFRM_TRANSFORMED)
5815 return NF_ACCEPT;
5816 break;
5817 case PF_INET6:
5818 if (IP6CB(skb)->flags & IP6SKB_XFRM_TRANSFORMED)
5819 return NF_ACCEPT;
5820 break;
5821 default:
5822 return NF_DROP_ERR(-ECONNREFUSED);
5823 }
5824 }
5825 if (selinux_conn_sid(sksec->sid, skb_sid, &peer_sid))
5826 return NF_DROP;
5827 secmark_perm = PACKET__SEND;
5828 } else {
5829 /* Locally generated packet, fetch the security label from the
5830 * associated socket. */
5831 struct sk_security_struct *sksec = sk->sk_security;
5832 peer_sid = sksec->sid;
5833 secmark_perm = PACKET__SEND;
5834 }
5835
5836 ad.type = LSM_AUDIT_DATA_NET;
5837 ad.u.net = &net;
5838 ad.u.net->netif = ifindex;
5839 ad.u.net->family = family;
5840 if (selinux_parse_skb(skb, &ad, &addrp, 0, NULL))
5841 return NF_DROP;
5842
5843 if (secmark_active)
5844 if (avc_has_perm(&selinux_state,
5845 peer_sid, skb->secmark,
5846 SECCLASS_PACKET, secmark_perm, &ad))
5847 return NF_DROP_ERR(-ECONNREFUSED);
5848
5849 if (peerlbl_active) {
5850 u32 if_sid;
5851 u32 node_sid;
5852
5853 if (sel_netif_sid(dev_net(outdev), ifindex, &if_sid))
5854 return NF_DROP;
5855 if (avc_has_perm(&selinux_state,
5856 peer_sid, if_sid,
5857 SECCLASS_NETIF, NETIF__EGRESS, &ad))
5858 return NF_DROP_ERR(-ECONNREFUSED);
5859
5860 if (sel_netnode_sid(addrp, family, &node_sid))
5861 return NF_DROP;
5862 if (avc_has_perm(&selinux_state,
5863 peer_sid, node_sid,
5864 SECCLASS_NODE, NODE__SENDTO, &ad))
5865 return NF_DROP_ERR(-ECONNREFUSED);
5866 }
5867
5868 return NF_ACCEPT;
5869}
5870
5871static unsigned int selinux_ipv4_postroute(void *priv,
5872 struct sk_buff *skb,
5873 const struct nf_hook_state *state)
5874{
5875 return selinux_ip_postroute(skb, state->out, PF_INET);
5876}
5877
5878#if IS_ENABLED(CONFIG_IPV6)
5879static unsigned int selinux_ipv6_postroute(void *priv,
5880 struct sk_buff *skb,
5881 const struct nf_hook_state *state)
5882{
5883 return selinux_ip_postroute(skb, state->out, PF_INET6);
5884}
5885#endif /* IPV6 */
5886
5887#endif /* CONFIG_NETFILTER */
5888
5889static int selinux_netlink_send(struct sock *sk, struct sk_buff *skb)
5890{
5891 return selinux_nlmsg_perm(sk, skb);
5892}
5893
5894static int ipc_alloc_security(struct kern_ipc_perm *perm,
5895 u16 sclass)
5896{
5897 struct ipc_security_struct *isec;
5898
5899 isec = kzalloc(sizeof(struct ipc_security_struct), GFP_KERNEL);
5900 if (!isec)
5901 return -ENOMEM;
5902
5903 isec->sclass = sclass;
5904 isec->sid = current_sid();
5905 perm->security = isec;
5906
5907 return 0;
5908}
5909
5910static void ipc_free_security(struct kern_ipc_perm *perm)
5911{
5912 struct ipc_security_struct *isec = perm->security;
5913 perm->security = NULL;
5914 kfree(isec);
5915}
5916
5917static int msg_msg_alloc_security(struct msg_msg *msg)
5918{
5919 struct msg_security_struct *msec;
5920
5921 msec = kzalloc(sizeof(struct msg_security_struct), GFP_KERNEL);
5922 if (!msec)
5923 return -ENOMEM;
5924
5925 msec->sid = SECINITSID_UNLABELED;
5926 msg->security = msec;
5927
5928 return 0;
5929}
5930
5931static void msg_msg_free_security(struct msg_msg *msg)
5932{
5933 struct msg_security_struct *msec = msg->security;
5934
5935 msg->security = NULL;
5936 kfree(msec);
5937}
5938
5939static int ipc_has_perm(struct kern_ipc_perm *ipc_perms,
5940 u32 perms)
5941{
5942 struct ipc_security_struct *isec;
5943 struct common_audit_data ad;
5944 u32 sid = current_sid();
5945
5946 isec = ipc_perms->security;
5947
5948 ad.type = LSM_AUDIT_DATA_IPC;
5949 ad.u.ipc_id = ipc_perms->key;
5950
5951 return avc_has_perm(&selinux_state,
5952 sid, isec->sid, isec->sclass, perms, &ad);
5953}
5954
5955static int selinux_msg_msg_alloc_security(struct msg_msg *msg)
5956{
5957 return msg_msg_alloc_security(msg);
5958}
5959
5960static void selinux_msg_msg_free_security(struct msg_msg *msg)
5961{
5962 msg_msg_free_security(msg);
5963}
5964
5965/* message queue security operations */
5966static int selinux_msg_queue_alloc_security(struct kern_ipc_perm *msq)
5967{
5968 struct ipc_security_struct *isec;
5969 struct common_audit_data ad;
5970 u32 sid = current_sid();
5971 int rc;
5972
5973 rc = ipc_alloc_security(msq, SECCLASS_MSGQ);
5974 if (rc)
5975 return rc;
5976
5977 isec = msq->security;
5978
5979 ad.type = LSM_AUDIT_DATA_IPC;
5980 ad.u.ipc_id = msq->key;
5981
5982 rc = avc_has_perm(&selinux_state,
5983 sid, isec->sid, SECCLASS_MSGQ,
5984 MSGQ__CREATE, &ad);
5985 if (rc) {
5986 ipc_free_security(msq);
5987 return rc;
5988 }
5989 return 0;
5990}
5991
5992static void selinux_msg_queue_free_security(struct kern_ipc_perm *msq)
5993{
5994 ipc_free_security(msq);
5995}
5996
5997static int selinux_msg_queue_associate(struct kern_ipc_perm *msq, int msqflg)
5998{
5999 struct ipc_security_struct *isec;
6000 struct common_audit_data ad;
6001 u32 sid = current_sid();
6002
6003 isec = msq->security;
6004
6005 ad.type = LSM_AUDIT_DATA_IPC;
6006 ad.u.ipc_id = msq->key;
6007
6008 return avc_has_perm(&selinux_state,
6009 sid, isec->sid, SECCLASS_MSGQ,
6010 MSGQ__ASSOCIATE, &ad);
6011}
6012
6013static int selinux_msg_queue_msgctl(struct kern_ipc_perm *msq, int cmd)
6014{
6015 int err;
6016 int perms;
6017
6018 switch (cmd) {
6019 case IPC_INFO:
6020 case MSG_INFO:
6021 /* No specific object, just general system-wide information. */
6022 return avc_has_perm(&selinux_state,
6023 current_sid(), SECINITSID_KERNEL,
6024 SECCLASS_SYSTEM, SYSTEM__IPC_INFO, NULL);
6025 case IPC_STAT:
6026 case MSG_STAT:
6027 case MSG_STAT_ANY:
6028 perms = MSGQ__GETATTR | MSGQ__ASSOCIATE;
6029 break;
6030 case IPC_SET:
6031 perms = MSGQ__SETATTR;
6032 break;
6033 case IPC_RMID:
6034 perms = MSGQ__DESTROY;
6035 break;
6036 default:
6037 return 0;
6038 }
6039
6040 err = ipc_has_perm(msq, perms);
6041 return err;
6042}
6043
6044static int selinux_msg_queue_msgsnd(struct kern_ipc_perm *msq, struct msg_msg *msg, int msqflg)
6045{
6046 struct ipc_security_struct *isec;
6047 struct msg_security_struct *msec;
6048 struct common_audit_data ad;
6049 u32 sid = current_sid();
6050 int rc;
6051
6052 isec = msq->security;
6053 msec = msg->security;
6054
6055 /*
6056 * First time through, need to assign label to the message
6057 */
6058 if (msec->sid == SECINITSID_UNLABELED) {
6059 /*
6060 * Compute new sid based on current process and
6061 * message queue this message will be stored in
6062 */
6063 rc = security_transition_sid(&selinux_state, sid, isec->sid,
6064 SECCLASS_MSG, NULL, &msec->sid);
6065 if (rc)
6066 return rc;
6067 }
6068
6069 ad.type = LSM_AUDIT_DATA_IPC;
6070 ad.u.ipc_id = msq->key;
6071
6072 /* Can this process write to the queue? */
6073 rc = avc_has_perm(&selinux_state,
6074 sid, isec->sid, SECCLASS_MSGQ,
6075 MSGQ__WRITE, &ad);
6076 if (!rc)
6077 /* Can this process send the message */
6078 rc = avc_has_perm(&selinux_state,
6079 sid, msec->sid, SECCLASS_MSG,
6080 MSG__SEND, &ad);
6081 if (!rc)
6082 /* Can the message be put in the queue? */
6083 rc = avc_has_perm(&selinux_state,
6084 msec->sid, isec->sid, SECCLASS_MSGQ,
6085 MSGQ__ENQUEUE, &ad);
6086
6087 return rc;
6088}
6089
6090static int selinux_msg_queue_msgrcv(struct kern_ipc_perm *msq, struct msg_msg *msg,
6091 struct task_struct *target,
6092 long type, int mode)
6093{
6094 struct ipc_security_struct *isec;
6095 struct msg_security_struct *msec;
6096 struct common_audit_data ad;
6097 u32 sid = task_sid(target);
6098 int rc;
6099
6100 isec = msq->security;
6101 msec = msg->security;
6102
6103 ad.type = LSM_AUDIT_DATA_IPC;
6104 ad.u.ipc_id = msq->key;
6105
6106 rc = avc_has_perm(&selinux_state,
6107 sid, isec->sid,
6108 SECCLASS_MSGQ, MSGQ__READ, &ad);
6109 if (!rc)
6110 rc = avc_has_perm(&selinux_state,
6111 sid, msec->sid,
6112 SECCLASS_MSG, MSG__RECEIVE, &ad);
6113 return rc;
6114}
6115
6116/* Shared Memory security operations */
6117static int selinux_shm_alloc_security(struct kern_ipc_perm *shp)
6118{
6119 struct ipc_security_struct *isec;
6120 struct common_audit_data ad;
6121 u32 sid = current_sid();
6122 int rc;
6123
6124 rc = ipc_alloc_security(shp, SECCLASS_SHM);
6125 if (rc)
6126 return rc;
6127
6128 isec = shp->security;
6129
6130 ad.type = LSM_AUDIT_DATA_IPC;
6131 ad.u.ipc_id = shp->key;
6132
6133 rc = avc_has_perm(&selinux_state,
6134 sid, isec->sid, SECCLASS_SHM,
6135 SHM__CREATE, &ad);
6136 if (rc) {
6137 ipc_free_security(shp);
6138 return rc;
6139 }
6140 return 0;
6141}
6142
6143static void selinux_shm_free_security(struct kern_ipc_perm *shp)
6144{
6145 ipc_free_security(shp);
6146}
6147
6148static int selinux_shm_associate(struct kern_ipc_perm *shp, int shmflg)
6149{
6150 struct ipc_security_struct *isec;
6151 struct common_audit_data ad;
6152 u32 sid = current_sid();
6153
6154 isec = shp->security;
6155
6156 ad.type = LSM_AUDIT_DATA_IPC;
6157 ad.u.ipc_id = shp->key;
6158
6159 return avc_has_perm(&selinux_state,
6160 sid, isec->sid, SECCLASS_SHM,
6161 SHM__ASSOCIATE, &ad);
6162}
6163
6164/* Note, at this point, shp is locked down */
6165static int selinux_shm_shmctl(struct kern_ipc_perm *shp, int cmd)
6166{
6167 int perms;
6168 int err;
6169
6170 switch (cmd) {
6171 case IPC_INFO:
6172 case SHM_INFO:
6173 /* No specific object, just general system-wide information. */
6174 return avc_has_perm(&selinux_state,
6175 current_sid(), SECINITSID_KERNEL,
6176 SECCLASS_SYSTEM, SYSTEM__IPC_INFO, NULL);
6177 case IPC_STAT:
6178 case SHM_STAT:
6179 case SHM_STAT_ANY:
6180 perms = SHM__GETATTR | SHM__ASSOCIATE;
6181 break;
6182 case IPC_SET:
6183 perms = SHM__SETATTR;
6184 break;
6185 case SHM_LOCK:
6186 case SHM_UNLOCK:
6187 perms = SHM__LOCK;
6188 break;
6189 case IPC_RMID:
6190 perms = SHM__DESTROY;
6191 break;
6192 default:
6193 return 0;
6194 }
6195
6196 err = ipc_has_perm(shp, perms);
6197 return err;
6198}
6199
6200static int selinux_shm_shmat(struct kern_ipc_perm *shp,
6201 char __user *shmaddr, int shmflg)
6202{
6203 u32 perms;
6204
6205 if (shmflg & SHM_RDONLY)
6206 perms = SHM__READ;
6207 else
6208 perms = SHM__READ | SHM__WRITE;
6209
6210 return ipc_has_perm(shp, perms);
6211}
6212
6213/* Semaphore security operations */
6214static int selinux_sem_alloc_security(struct kern_ipc_perm *sma)
6215{
6216 struct ipc_security_struct *isec;
6217 struct common_audit_data ad;
6218 u32 sid = current_sid();
6219 int rc;
6220
6221 rc = ipc_alloc_security(sma, SECCLASS_SEM);
6222 if (rc)
6223 return rc;
6224
6225 isec = sma->security;
6226
6227 ad.type = LSM_AUDIT_DATA_IPC;
6228 ad.u.ipc_id = sma->key;
6229
6230 rc = avc_has_perm(&selinux_state,
6231 sid, isec->sid, SECCLASS_SEM,
6232 SEM__CREATE, &ad);
6233 if (rc) {
6234 ipc_free_security(sma);
6235 return rc;
6236 }
6237 return 0;
6238}
6239
6240static void selinux_sem_free_security(struct kern_ipc_perm *sma)
6241{
6242 ipc_free_security(sma);
6243}
6244
6245static int selinux_sem_associate(struct kern_ipc_perm *sma, int semflg)
6246{
6247 struct ipc_security_struct *isec;
6248 struct common_audit_data ad;
6249 u32 sid = current_sid();
6250
6251 isec = sma->security;
6252
6253 ad.type = LSM_AUDIT_DATA_IPC;
6254 ad.u.ipc_id = sma->key;
6255
6256 return avc_has_perm(&selinux_state,
6257 sid, isec->sid, SECCLASS_SEM,
6258 SEM__ASSOCIATE, &ad);
6259}
6260
6261/* Note, at this point, sma is locked down */
6262static int selinux_sem_semctl(struct kern_ipc_perm *sma, int cmd)
6263{
6264 int err;
6265 u32 perms;
6266
6267 switch (cmd) {
6268 case IPC_INFO:
6269 case SEM_INFO:
6270 /* No specific object, just general system-wide information. */
6271 return avc_has_perm(&selinux_state,
6272 current_sid(), SECINITSID_KERNEL,
6273 SECCLASS_SYSTEM, SYSTEM__IPC_INFO, NULL);
6274 case GETPID:
6275 case GETNCNT:
6276 case GETZCNT:
6277 perms = SEM__GETATTR;
6278 break;
6279 case GETVAL:
6280 case GETALL:
6281 perms = SEM__READ;
6282 break;
6283 case SETVAL:
6284 case SETALL:
6285 perms = SEM__WRITE;
6286 break;
6287 case IPC_RMID:
6288 perms = SEM__DESTROY;
6289 break;
6290 case IPC_SET:
6291 perms = SEM__SETATTR;
6292 break;
6293 case IPC_STAT:
6294 case SEM_STAT:
6295 case SEM_STAT_ANY:
6296 perms = SEM__GETATTR | SEM__ASSOCIATE;
6297 break;
6298 default:
6299 return 0;
6300 }
6301
6302 err = ipc_has_perm(sma, perms);
6303 return err;
6304}
6305
6306static int selinux_sem_semop(struct kern_ipc_perm *sma,
6307 struct sembuf *sops, unsigned nsops, int alter)
6308{
6309 u32 perms;
6310
6311 if (alter)
6312 perms = SEM__READ | SEM__WRITE;
6313 else
6314 perms = SEM__READ;
6315
6316 return ipc_has_perm(sma, perms);
6317}
6318
6319static int selinux_ipc_permission(struct kern_ipc_perm *ipcp, short flag)
6320{
6321 u32 av = 0;
6322
6323 av = 0;
6324 if (flag & S_IRUGO)
6325 av |= IPC__UNIX_READ;
6326 if (flag & S_IWUGO)
6327 av |= IPC__UNIX_WRITE;
6328
6329 if (av == 0)
6330 return 0;
6331
6332 return ipc_has_perm(ipcp, av);
6333}
6334
6335static void selinux_ipc_getsecid(struct kern_ipc_perm *ipcp, u32 *secid)
6336{
6337 struct ipc_security_struct *isec = ipcp->security;
6338 *secid = isec->sid;
6339}
6340
6341static void selinux_d_instantiate(struct dentry *dentry, struct inode *inode)
6342{
6343 if (inode)
6344 inode_doinit_with_dentry(inode, dentry);
6345}
6346
6347static int selinux_getprocattr(struct task_struct *p,
6348 char *name, char **value)
6349{
6350 const struct task_security_struct *__tsec;
6351 u32 sid;
6352 int error;
6353 unsigned len;
6354
6355 rcu_read_lock();
6356 __tsec = __task_cred(p)->security;
6357
6358 if (current != p) {
6359 error = avc_has_perm(&selinux_state,
6360 current_sid(), __tsec->sid,
6361 SECCLASS_PROCESS, PROCESS__GETATTR, NULL);
6362 if (error)
6363 goto bad;
6364 }
6365
6366 if (!strcmp(name, "current"))
6367 sid = __tsec->sid;
6368 else if (!strcmp(name, "prev"))
6369 sid = __tsec->osid;
6370 else if (!strcmp(name, "exec"))
6371 sid = __tsec->exec_sid;
6372 else if (!strcmp(name, "fscreate"))
6373 sid = __tsec->create_sid;
6374 else if (!strcmp(name, "keycreate"))
6375 sid = __tsec->keycreate_sid;
6376 else if (!strcmp(name, "sockcreate"))
6377 sid = __tsec->sockcreate_sid;
6378 else {
6379 error = -EINVAL;
6380 goto bad;
6381 }
6382 rcu_read_unlock();
6383
6384 if (!sid)
6385 return 0;
6386
6387 error = security_sid_to_context(&selinux_state, sid, value, &len);
6388 if (error)
6389 return error;
6390 return len;
6391
6392bad:
6393 rcu_read_unlock();
6394 return error;
6395}
6396
6397static int selinux_setprocattr(const char *name, void *value, size_t size)
6398{
6399 struct task_security_struct *tsec;
6400 struct cred *new;
6401 u32 mysid = current_sid(), sid = 0, ptsid;
6402 int error;
6403 char *str = value;
6404
6405 /*
6406 * Basic control over ability to set these attributes at all.
6407 */
6408 if (!strcmp(name, "exec"))
6409 error = avc_has_perm(&selinux_state,
6410 mysid, mysid, SECCLASS_PROCESS,
6411 PROCESS__SETEXEC, NULL);
6412 else if (!strcmp(name, "fscreate"))
6413 error = avc_has_perm(&selinux_state,
6414 mysid, mysid, SECCLASS_PROCESS,
6415 PROCESS__SETFSCREATE, NULL);
6416 else if (!strcmp(name, "keycreate"))
6417 error = avc_has_perm(&selinux_state,
6418 mysid, mysid, SECCLASS_PROCESS,
6419 PROCESS__SETKEYCREATE, NULL);
6420 else if (!strcmp(name, "sockcreate"))
6421 error = avc_has_perm(&selinux_state,
6422 mysid, mysid, SECCLASS_PROCESS,
6423 PROCESS__SETSOCKCREATE, NULL);
6424 else if (!strcmp(name, "current"))
6425 error = avc_has_perm(&selinux_state,
6426 mysid, mysid, SECCLASS_PROCESS,
6427 PROCESS__SETCURRENT, NULL);
6428 else
6429 error = -EINVAL;
6430 if (error)
6431 return error;
6432
6433 /* Obtain a SID for the context, if one was specified. */
6434 if (size && str[0] && str[0] != '\n') {
6435 if (str[size-1] == '\n') {
6436 str[size-1] = 0;
6437 size--;
6438 }
6439 error = security_context_to_sid(&selinux_state, value, size,
6440 &sid, GFP_KERNEL);
6441 if (error == -EINVAL && !strcmp(name, "fscreate")) {
6442 if (!has_cap_mac_admin(true)) {
6443 struct audit_buffer *ab;
6444 size_t audit_size;
6445
6446 /* We strip a nul only if it is at the end, otherwise the
6447 * context contains a nul and we should audit that */
6448 if (str[size - 1] == '\0')
6449 audit_size = size - 1;
6450 else
6451 audit_size = size;
6452 ab = audit_log_start(current->audit_context, GFP_ATOMIC, AUDIT_SELINUX_ERR);
6453 audit_log_format(ab, "op=fscreate invalid_context=");
6454 audit_log_n_untrustedstring(ab, value, audit_size);
6455 audit_log_end(ab);
6456
6457 return error;
6458 }
6459 error = security_context_to_sid_force(
6460 &selinux_state,
6461 value, size, &sid);
6462 }
6463 if (error)
6464 return error;
6465 }
6466
6467 new = prepare_creds();
6468 if (!new)
6469 return -ENOMEM;
6470
6471 /* Permission checking based on the specified context is
6472 performed during the actual operation (execve,
6473 open/mkdir/...), when we know the full context of the
6474 operation. See selinux_bprm_set_creds for the execve
6475 checks and may_create for the file creation checks. The
6476 operation will then fail if the context is not permitted. */
6477 tsec = new->security;
6478 if (!strcmp(name, "exec")) {
6479 tsec->exec_sid = sid;
6480 } else if (!strcmp(name, "fscreate")) {
6481 tsec->create_sid = sid;
6482 } else if (!strcmp(name, "keycreate")) {
6483 error = avc_has_perm(&selinux_state,
6484 mysid, sid, SECCLASS_KEY, KEY__CREATE,
6485 NULL);
6486 if (error)
6487 goto abort_change;
6488 tsec->keycreate_sid = sid;
6489 } else if (!strcmp(name, "sockcreate")) {
6490 tsec->sockcreate_sid = sid;
6491 } else if (!strcmp(name, "current")) {
6492 error = -EINVAL;
6493 if (sid == 0)
6494 goto abort_change;
6495
6496 /* Only allow single threaded processes to change context */
6497 error = -EPERM;
6498 if (!current_is_single_threaded()) {
6499 error = security_bounded_transition(&selinux_state,
6500 tsec->sid, sid);
6501 if (error)
6502 goto abort_change;
6503 }
6504
6505 /* Check permissions for the transition. */
6506 error = avc_has_perm(&selinux_state,
6507 tsec->sid, sid, SECCLASS_PROCESS,
6508 PROCESS__DYNTRANSITION, NULL);
6509 if (error)
6510 goto abort_change;
6511
6512 /* Check for ptracing, and update the task SID if ok.
6513 Otherwise, leave SID unchanged and fail. */
6514 ptsid = ptrace_parent_sid();
6515 if (ptsid != 0) {
6516 error = avc_has_perm(&selinux_state,
6517 ptsid, sid, SECCLASS_PROCESS,
6518 PROCESS__PTRACE, NULL);
6519 if (error)
6520 goto abort_change;
6521 }
6522
6523 tsec->sid = sid;
6524 } else {
6525 error = -EINVAL;
6526 goto abort_change;
6527 }
6528
6529 commit_creds(new);
6530 return size;
6531
6532abort_change:
6533 abort_creds(new);
6534 return error;
6535}
6536
6537static int selinux_ismaclabel(const char *name)
6538{
6539 return (strcmp(name, XATTR_SELINUX_SUFFIX) == 0);
6540}
6541
6542static int selinux_secid_to_secctx(u32 secid, char **secdata, u32 *seclen)
6543{
6544 return security_sid_to_context(&selinux_state, secid,
6545 secdata, seclen);
6546}
6547
6548static int selinux_secctx_to_secid(const char *secdata, u32 seclen, u32 *secid)
6549{
6550 return security_context_to_sid(&selinux_state, secdata, seclen,
6551 secid, GFP_KERNEL);
6552}
6553
6554static void selinux_release_secctx(char *secdata, u32 seclen)
6555{
6556 kfree(secdata);
6557}
6558
6559static void selinux_inode_invalidate_secctx(struct inode *inode)
6560{
6561 struct inode_security_struct *isec = inode->i_security;
6562
6563 spin_lock(&isec->lock);
6564 isec->initialized = LABEL_INVALID;
6565 spin_unlock(&isec->lock);
6566}
6567
6568/*
6569 * called with inode->i_mutex locked
6570 */
6571static int selinux_inode_notifysecctx(struct inode *inode, void *ctx, u32 ctxlen)
6572{
6573 return selinux_inode_setsecurity(inode, XATTR_SELINUX_SUFFIX, ctx, ctxlen, 0);
6574}
6575
6576/*
6577 * called with inode->i_mutex locked
6578 */
6579static int selinux_inode_setsecctx(struct dentry *dentry, void *ctx, u32 ctxlen)
6580{
6581 return __vfs_setxattr_noperm(dentry, XATTR_NAME_SELINUX, ctx, ctxlen, 0);
6582}
6583
6584static int selinux_inode_getsecctx(struct inode *inode, void **ctx, u32 *ctxlen)
6585{
6586 int len = 0;
6587 len = selinux_inode_getsecurity(inode, XATTR_SELINUX_SUFFIX,
6588 ctx, true);
6589 if (len < 0)
6590 return len;
6591 *ctxlen = len;
6592 return 0;
6593}
6594#ifdef CONFIG_KEYS
6595
6596static int selinux_key_alloc(struct key *k, const struct cred *cred,
6597 unsigned long flags)
6598{
6599 const struct task_security_struct *tsec;
6600 struct key_security_struct *ksec;
6601
6602 ksec = kzalloc(sizeof(struct key_security_struct), GFP_KERNEL);
6603 if (!ksec)
6604 return -ENOMEM;
6605
6606 tsec = cred->security;
6607 if (tsec->keycreate_sid)
6608 ksec->sid = tsec->keycreate_sid;
6609 else
6610 ksec->sid = tsec->sid;
6611
6612 k->security = ksec;
6613 return 0;
6614}
6615
6616static void selinux_key_free(struct key *k)
6617{
6618 struct key_security_struct *ksec = k->security;
6619
6620 k->security = NULL;
6621 kfree(ksec);
6622}
6623
6624static int selinux_key_permission(key_ref_t key_ref,
6625 const struct cred *cred,
6626 unsigned perm)
6627{
6628 struct key *key;
6629 struct key_security_struct *ksec;
6630 u32 sid;
6631
6632 /* if no specific permissions are requested, we skip the
6633 permission check. No serious, additional covert channels
6634 appear to be created. */
6635 if (perm == 0)
6636 return 0;
6637
6638 sid = cred_sid(cred);
6639
6640 key = key_ref_to_ptr(key_ref);
6641 ksec = key->security;
6642
6643 return avc_has_perm(&selinux_state,
6644 sid, ksec->sid, SECCLASS_KEY, perm, NULL);
6645}
6646
6647static int selinux_key_getsecurity(struct key *key, char **_buffer)
6648{
6649 struct key_security_struct *ksec = key->security;
6650 char *context = NULL;
6651 unsigned len;
6652 int rc;
6653
6654 rc = security_sid_to_context(&selinux_state, ksec->sid,
6655 &context, &len);
6656 if (!rc)
6657 rc = len;
6658 *_buffer = context;
6659 return rc;
6660}
6661#endif
6662
6663#ifdef CONFIG_SECURITY_INFINIBAND
6664static int selinux_ib_pkey_access(void *ib_sec, u64 subnet_prefix, u16 pkey_val)
6665{
6666 struct common_audit_data ad;
6667 int err;
6668 u32 sid = 0;
6669 struct ib_security_struct *sec = ib_sec;
6670 struct lsm_ibpkey_audit ibpkey;
6671
6672 err = sel_ib_pkey_sid(subnet_prefix, pkey_val, &sid);
6673 if (err)
6674 return err;
6675
6676 ad.type = LSM_AUDIT_DATA_IBPKEY;
6677 ibpkey.subnet_prefix = subnet_prefix;
6678 ibpkey.pkey = pkey_val;
6679 ad.u.ibpkey = &ibpkey;
6680 return avc_has_perm(&selinux_state,
6681 sec->sid, sid,
6682 SECCLASS_INFINIBAND_PKEY,
6683 INFINIBAND_PKEY__ACCESS, &ad);
6684}
6685
6686static int selinux_ib_endport_manage_subnet(void *ib_sec, const char *dev_name,
6687 u8 port_num)
6688{
6689 struct common_audit_data ad;
6690 int err;
6691 u32 sid = 0;
6692 struct ib_security_struct *sec = ib_sec;
6693 struct lsm_ibendport_audit ibendport;
6694
6695 err = security_ib_endport_sid(&selinux_state, dev_name, port_num,
6696 &sid);
6697
6698 if (err)
6699 return err;
6700
6701 ad.type = LSM_AUDIT_DATA_IBENDPORT;
6702 strncpy(ibendport.dev_name, dev_name, sizeof(ibendport.dev_name));
6703 ibendport.port = port_num;
6704 ad.u.ibendport = &ibendport;
6705 return avc_has_perm(&selinux_state,
6706 sec->sid, sid,
6707 SECCLASS_INFINIBAND_ENDPORT,
6708 INFINIBAND_ENDPORT__MANAGE_SUBNET, &ad);
6709}
6710
6711static int selinux_ib_alloc_security(void **ib_sec)
6712{
6713 struct ib_security_struct *sec;
6714
6715 sec = kzalloc(sizeof(*sec), GFP_KERNEL);
6716 if (!sec)
6717 return -ENOMEM;
6718 sec->sid = current_sid();
6719
6720 *ib_sec = sec;
6721 return 0;
6722}
6723
6724static void selinux_ib_free_security(void *ib_sec)
6725{
6726 kfree(ib_sec);
6727}
6728#endif
6729
6730#ifdef CONFIG_BPF_SYSCALL
6731static int selinux_bpf(int cmd, union bpf_attr *attr,
6732 unsigned int size)
6733{
6734 u32 sid = current_sid();
6735 int ret;
6736
6737 switch (cmd) {
6738 case BPF_MAP_CREATE:
6739 ret = avc_has_perm(&selinux_state,
6740 sid, sid, SECCLASS_BPF, BPF__MAP_CREATE,
6741 NULL);
6742 break;
6743 case BPF_PROG_LOAD:
6744 ret = avc_has_perm(&selinux_state,
6745 sid, sid, SECCLASS_BPF, BPF__PROG_LOAD,
6746 NULL);
6747 break;
6748 default:
6749 ret = 0;
6750 break;
6751 }
6752
6753 return ret;
6754}
6755
6756static u32 bpf_map_fmode_to_av(fmode_t fmode)
6757{
6758 u32 av = 0;
6759
6760 if (fmode & FMODE_READ)
6761 av |= BPF__MAP_READ;
6762 if (fmode & FMODE_WRITE)
6763 av |= BPF__MAP_WRITE;
6764 return av;
6765}
6766
6767/* This function will check the file pass through unix socket or binder to see
6768 * if it is a bpf related object. And apply correspinding checks on the bpf
6769 * object based on the type. The bpf maps and programs, not like other files and
6770 * socket, are using a shared anonymous inode inside the kernel as their inode.
6771 * So checking that inode cannot identify if the process have privilege to
6772 * access the bpf object and that's why we have to add this additional check in
6773 * selinux_file_receive and selinux_binder_transfer_files.
6774 */
6775static int bpf_fd_pass(struct file *file, u32 sid)
6776{
6777 struct bpf_security_struct *bpfsec;
6778 struct bpf_prog *prog;
6779 struct bpf_map *map;
6780 int ret;
6781
6782 if (file->f_op == &bpf_map_fops) {
6783 map = file->private_data;
6784 bpfsec = map->security;
6785 ret = avc_has_perm(&selinux_state,
6786 sid, bpfsec->sid, SECCLASS_BPF,
6787 bpf_map_fmode_to_av(file->f_mode), NULL);
6788 if (ret)
6789 return ret;
6790 } else if (file->f_op == &bpf_prog_fops) {
6791 prog = file->private_data;
6792 bpfsec = prog->aux->security;
6793 ret = avc_has_perm(&selinux_state,
6794 sid, bpfsec->sid, SECCLASS_BPF,
6795 BPF__PROG_RUN, NULL);
6796 if (ret)
6797 return ret;
6798 }
6799 return 0;
6800}
6801
6802static int selinux_bpf_map(struct bpf_map *map, fmode_t fmode)
6803{
6804 u32 sid = current_sid();
6805 struct bpf_security_struct *bpfsec;
6806
6807 bpfsec = map->security;
6808 return avc_has_perm(&selinux_state,
6809 sid, bpfsec->sid, SECCLASS_BPF,
6810 bpf_map_fmode_to_av(fmode), NULL);
6811}
6812
6813static int selinux_bpf_prog(struct bpf_prog *prog)
6814{
6815 u32 sid = current_sid();
6816 struct bpf_security_struct *bpfsec;
6817
6818 bpfsec = prog->aux->security;
6819 return avc_has_perm(&selinux_state,
6820 sid, bpfsec->sid, SECCLASS_BPF,
6821 BPF__PROG_RUN, NULL);
6822}
6823
6824static int selinux_bpf_map_alloc(struct bpf_map *map)
6825{
6826 struct bpf_security_struct *bpfsec;
6827
6828 bpfsec = kzalloc(sizeof(*bpfsec), GFP_KERNEL);
6829 if (!bpfsec)
6830 return -ENOMEM;
6831
6832 bpfsec->sid = current_sid();
6833 map->security = bpfsec;
6834
6835 return 0;
6836}
6837
6838static void selinux_bpf_map_free(struct bpf_map *map)
6839{
6840 struct bpf_security_struct *bpfsec = map->security;
6841
6842 map->security = NULL;
6843 kfree(bpfsec);
6844}
6845
6846static int selinux_bpf_prog_alloc(struct bpf_prog_aux *aux)
6847{
6848 struct bpf_security_struct *bpfsec;
6849
6850 bpfsec = kzalloc(sizeof(*bpfsec), GFP_KERNEL);
6851 if (!bpfsec)
6852 return -ENOMEM;
6853
6854 bpfsec->sid = current_sid();
6855 aux->security = bpfsec;
6856
6857 return 0;
6858}
6859
6860static void selinux_bpf_prog_free(struct bpf_prog_aux *aux)
6861{
6862 struct bpf_security_struct *bpfsec = aux->security;
6863
6864 aux->security = NULL;
6865 kfree(bpfsec);
6866}
6867#endif
6868
6869static struct security_hook_list selinux_hooks[] __lsm_ro_after_init = {
6870 LSM_HOOK_INIT(binder_set_context_mgr, selinux_binder_set_context_mgr),
6871 LSM_HOOK_INIT(binder_transaction, selinux_binder_transaction),
6872 LSM_HOOK_INIT(binder_transfer_binder, selinux_binder_transfer_binder),
6873 LSM_HOOK_INIT(binder_transfer_file, selinux_binder_transfer_file),
6874
6875 LSM_HOOK_INIT(ptrace_access_check, selinux_ptrace_access_check),
6876 LSM_HOOK_INIT(ptrace_traceme, selinux_ptrace_traceme),
6877 LSM_HOOK_INIT(capget, selinux_capget),
6878 LSM_HOOK_INIT(capset, selinux_capset),
6879 LSM_HOOK_INIT(capable, selinux_capable),
6880 LSM_HOOK_INIT(quotactl, selinux_quotactl),
6881 LSM_HOOK_INIT(quota_on, selinux_quota_on),
6882 LSM_HOOK_INIT(syslog, selinux_syslog),
6883 LSM_HOOK_INIT(vm_enough_memory, selinux_vm_enough_memory),
6884
6885 LSM_HOOK_INIT(netlink_send, selinux_netlink_send),
6886
6887 LSM_HOOK_INIT(bprm_set_creds, selinux_bprm_set_creds),
6888 LSM_HOOK_INIT(bprm_committing_creds, selinux_bprm_committing_creds),
6889 LSM_HOOK_INIT(bprm_committed_creds, selinux_bprm_committed_creds),
6890
6891 LSM_HOOK_INIT(sb_alloc_security, selinux_sb_alloc_security),
6892 LSM_HOOK_INIT(sb_free_security, selinux_sb_free_security),
6893 LSM_HOOK_INIT(sb_copy_data, selinux_sb_copy_data),
6894 LSM_HOOK_INIT(sb_remount, selinux_sb_remount),
6895 LSM_HOOK_INIT(sb_kern_mount, selinux_sb_kern_mount),
6896 LSM_HOOK_INIT(sb_show_options, selinux_sb_show_options),
6897 LSM_HOOK_INIT(sb_statfs, selinux_sb_statfs),
6898 LSM_HOOK_INIT(sb_mount, selinux_mount),
6899 LSM_HOOK_INIT(sb_umount, selinux_umount),
6900 LSM_HOOK_INIT(sb_set_mnt_opts, selinux_set_mnt_opts),
6901 LSM_HOOK_INIT(sb_clone_mnt_opts, selinux_sb_clone_mnt_opts),
6902 LSM_HOOK_INIT(sb_parse_opts_str, selinux_parse_opts_str),
6903
6904 LSM_HOOK_INIT(dentry_init_security, selinux_dentry_init_security),
6905 LSM_HOOK_INIT(dentry_create_files_as, selinux_dentry_create_files_as),
6906
6907 LSM_HOOK_INIT(inode_alloc_security, selinux_inode_alloc_security),
6908 LSM_HOOK_INIT(inode_free_security, selinux_inode_free_security),
6909 LSM_HOOK_INIT(inode_init_security, selinux_inode_init_security),
6910 LSM_HOOK_INIT(inode_create, selinux_inode_create),
6911 LSM_HOOK_INIT(inode_link, selinux_inode_link),
6912 LSM_HOOK_INIT(inode_unlink, selinux_inode_unlink),
6913 LSM_HOOK_INIT(inode_symlink, selinux_inode_symlink),
6914 LSM_HOOK_INIT(inode_mkdir, selinux_inode_mkdir),
6915 LSM_HOOK_INIT(inode_rmdir, selinux_inode_rmdir),
6916 LSM_HOOK_INIT(inode_mknod, selinux_inode_mknod),
6917 LSM_HOOK_INIT(inode_rename, selinux_inode_rename),
6918 LSM_HOOK_INIT(inode_readlink, selinux_inode_readlink),
6919 LSM_HOOK_INIT(inode_follow_link, selinux_inode_follow_link),
6920 LSM_HOOK_INIT(inode_permission, selinux_inode_permission),
6921 LSM_HOOK_INIT(inode_setattr, selinux_inode_setattr),
6922 LSM_HOOK_INIT(inode_getattr, selinux_inode_getattr),
6923 LSM_HOOK_INIT(inode_setxattr, selinux_inode_setxattr),
6924 LSM_HOOK_INIT(inode_post_setxattr, selinux_inode_post_setxattr),
6925 LSM_HOOK_INIT(inode_getxattr, selinux_inode_getxattr),
6926 LSM_HOOK_INIT(inode_listxattr, selinux_inode_listxattr),
6927 LSM_HOOK_INIT(inode_removexattr, selinux_inode_removexattr),
6928 LSM_HOOK_INIT(inode_getsecurity, selinux_inode_getsecurity),
6929 LSM_HOOK_INIT(inode_setsecurity, selinux_inode_setsecurity),
6930 LSM_HOOK_INIT(inode_listsecurity, selinux_inode_listsecurity),
6931 LSM_HOOK_INIT(inode_getsecid, selinux_inode_getsecid),
6932 LSM_HOOK_INIT(inode_copy_up, selinux_inode_copy_up),
6933 LSM_HOOK_INIT(inode_copy_up_xattr, selinux_inode_copy_up_xattr),
6934
6935 LSM_HOOK_INIT(file_permission, selinux_file_permission),
6936 LSM_HOOK_INIT(file_alloc_security, selinux_file_alloc_security),
6937 LSM_HOOK_INIT(file_free_security, selinux_file_free_security),
6938 LSM_HOOK_INIT(file_ioctl, selinux_file_ioctl),
6939 LSM_HOOK_INIT(mmap_file, selinux_mmap_file),
6940 LSM_HOOK_INIT(mmap_addr, selinux_mmap_addr),
6941 LSM_HOOK_INIT(file_mprotect, selinux_file_mprotect),
6942 LSM_HOOK_INIT(file_lock, selinux_file_lock),
6943 LSM_HOOK_INIT(file_fcntl, selinux_file_fcntl),
6944 LSM_HOOK_INIT(file_set_fowner, selinux_file_set_fowner),
6945 LSM_HOOK_INIT(file_send_sigiotask, selinux_file_send_sigiotask),
6946 LSM_HOOK_INIT(file_receive, selinux_file_receive),
6947
6948 LSM_HOOK_INIT(file_open, selinux_file_open),
6949
6950 LSM_HOOK_INIT(task_alloc, selinux_task_alloc),
6951 LSM_HOOK_INIT(cred_alloc_blank, selinux_cred_alloc_blank),
6952 LSM_HOOK_INIT(cred_free, selinux_cred_free),
6953 LSM_HOOK_INIT(cred_prepare, selinux_cred_prepare),
6954 LSM_HOOK_INIT(cred_transfer, selinux_cred_transfer),
6955 LSM_HOOK_INIT(cred_getsecid, selinux_cred_getsecid),
6956 LSM_HOOK_INIT(kernel_act_as, selinux_kernel_act_as),
6957 LSM_HOOK_INIT(kernel_create_files_as, selinux_kernel_create_files_as),
6958 LSM_HOOK_INIT(kernel_module_request, selinux_kernel_module_request),
6959 LSM_HOOK_INIT(kernel_read_file, selinux_kernel_read_file),
6960 LSM_HOOK_INIT(task_setpgid, selinux_task_setpgid),
6961 LSM_HOOK_INIT(task_getpgid, selinux_task_getpgid),
6962 LSM_HOOK_INIT(task_getsid, selinux_task_getsid),
6963 LSM_HOOK_INIT(task_getsecid, selinux_task_getsecid),
6964 LSM_HOOK_INIT(task_setnice, selinux_task_setnice),
6965 LSM_HOOK_INIT(task_setioprio, selinux_task_setioprio),
6966 LSM_HOOK_INIT(task_getioprio, selinux_task_getioprio),
6967 LSM_HOOK_INIT(task_prlimit, selinux_task_prlimit),
6968 LSM_HOOK_INIT(task_setrlimit, selinux_task_setrlimit),
6969 LSM_HOOK_INIT(task_setscheduler, selinux_task_setscheduler),
6970 LSM_HOOK_INIT(task_getscheduler, selinux_task_getscheduler),
6971 LSM_HOOK_INIT(task_movememory, selinux_task_movememory),
6972 LSM_HOOK_INIT(task_kill, selinux_task_kill),
6973 LSM_HOOK_INIT(task_to_inode, selinux_task_to_inode),
6974
6975 LSM_HOOK_INIT(ipc_permission, selinux_ipc_permission),
6976 LSM_HOOK_INIT(ipc_getsecid, selinux_ipc_getsecid),
6977
6978 LSM_HOOK_INIT(msg_msg_alloc_security, selinux_msg_msg_alloc_security),
6979 LSM_HOOK_INIT(msg_msg_free_security, selinux_msg_msg_free_security),
6980
6981 LSM_HOOK_INIT(msg_queue_alloc_security,
6982 selinux_msg_queue_alloc_security),
6983 LSM_HOOK_INIT(msg_queue_free_security, selinux_msg_queue_free_security),
6984 LSM_HOOK_INIT(msg_queue_associate, selinux_msg_queue_associate),
6985 LSM_HOOK_INIT(msg_queue_msgctl, selinux_msg_queue_msgctl),
6986 LSM_HOOK_INIT(msg_queue_msgsnd, selinux_msg_queue_msgsnd),
6987 LSM_HOOK_INIT(msg_queue_msgrcv, selinux_msg_queue_msgrcv),
6988
6989 LSM_HOOK_INIT(shm_alloc_security, selinux_shm_alloc_security),
6990 LSM_HOOK_INIT(shm_free_security, selinux_shm_free_security),
6991 LSM_HOOK_INIT(shm_associate, selinux_shm_associate),
6992 LSM_HOOK_INIT(shm_shmctl, selinux_shm_shmctl),
6993 LSM_HOOK_INIT(shm_shmat, selinux_shm_shmat),
6994
6995 LSM_HOOK_INIT(sem_alloc_security, selinux_sem_alloc_security),
6996 LSM_HOOK_INIT(sem_free_security, selinux_sem_free_security),
6997 LSM_HOOK_INIT(sem_associate, selinux_sem_associate),
6998 LSM_HOOK_INIT(sem_semctl, selinux_sem_semctl),
6999 LSM_HOOK_INIT(sem_semop, selinux_sem_semop),
7000
7001 LSM_HOOK_INIT(d_instantiate, selinux_d_instantiate),
7002
7003 LSM_HOOK_INIT(getprocattr, selinux_getprocattr),
7004 LSM_HOOK_INIT(setprocattr, selinux_setprocattr),
7005
7006 LSM_HOOK_INIT(ismaclabel, selinux_ismaclabel),
7007 LSM_HOOK_INIT(secid_to_secctx, selinux_secid_to_secctx),
7008 LSM_HOOK_INIT(secctx_to_secid, selinux_secctx_to_secid),
7009 LSM_HOOK_INIT(release_secctx, selinux_release_secctx),
7010 LSM_HOOK_INIT(inode_invalidate_secctx, selinux_inode_invalidate_secctx),
7011 LSM_HOOK_INIT(inode_notifysecctx, selinux_inode_notifysecctx),
7012 LSM_HOOK_INIT(inode_setsecctx, selinux_inode_setsecctx),
7013 LSM_HOOK_INIT(inode_getsecctx, selinux_inode_getsecctx),
7014
7015 LSM_HOOK_INIT(unix_stream_connect, selinux_socket_unix_stream_connect),
7016 LSM_HOOK_INIT(unix_may_send, selinux_socket_unix_may_send),
7017
7018 LSM_HOOK_INIT(socket_create, selinux_socket_create),
7019 LSM_HOOK_INIT(socket_post_create, selinux_socket_post_create),
7020 LSM_HOOK_INIT(socket_bind, selinux_socket_bind),
7021 LSM_HOOK_INIT(socket_connect, selinux_socket_connect),
7022 LSM_HOOK_INIT(socket_listen, selinux_socket_listen),
7023 LSM_HOOK_INIT(socket_accept, selinux_socket_accept),
7024 LSM_HOOK_INIT(socket_sendmsg, selinux_socket_sendmsg),
7025 LSM_HOOK_INIT(socket_recvmsg, selinux_socket_recvmsg),
7026 LSM_HOOK_INIT(socket_getsockname, selinux_socket_getsockname),
7027 LSM_HOOK_INIT(socket_getpeername, selinux_socket_getpeername),
7028 LSM_HOOK_INIT(socket_getsockopt, selinux_socket_getsockopt),
7029 LSM_HOOK_INIT(socket_setsockopt, selinux_socket_setsockopt),
7030 LSM_HOOK_INIT(socket_shutdown, selinux_socket_shutdown),
7031 LSM_HOOK_INIT(socket_sock_rcv_skb, selinux_socket_sock_rcv_skb),
7032 LSM_HOOK_INIT(socket_getpeersec_stream,
7033 selinux_socket_getpeersec_stream),
7034 LSM_HOOK_INIT(socket_getpeersec_dgram, selinux_socket_getpeersec_dgram),
7035 LSM_HOOK_INIT(sk_alloc_security, selinux_sk_alloc_security),
7036 LSM_HOOK_INIT(sk_free_security, selinux_sk_free_security),
7037 LSM_HOOK_INIT(sk_clone_security, selinux_sk_clone_security),
7038 LSM_HOOK_INIT(sk_getsecid, selinux_sk_getsecid),
7039 LSM_HOOK_INIT(sock_graft, selinux_sock_graft),
7040 LSM_HOOK_INIT(sctp_assoc_request, selinux_sctp_assoc_request),
7041 LSM_HOOK_INIT(sctp_sk_clone, selinux_sctp_sk_clone),
7042 LSM_HOOK_INIT(sctp_bind_connect, selinux_sctp_bind_connect),
7043 LSM_HOOK_INIT(inet_conn_request, selinux_inet_conn_request),
7044 LSM_HOOK_INIT(inet_csk_clone, selinux_inet_csk_clone),
7045 LSM_HOOK_INIT(inet_conn_established, selinux_inet_conn_established),
7046 LSM_HOOK_INIT(secmark_relabel_packet, selinux_secmark_relabel_packet),
7047 LSM_HOOK_INIT(secmark_refcount_inc, selinux_secmark_refcount_inc),
7048 LSM_HOOK_INIT(secmark_refcount_dec, selinux_secmark_refcount_dec),
7049 LSM_HOOK_INIT(req_classify_flow, selinux_req_classify_flow),
7050 LSM_HOOK_INIT(tun_dev_alloc_security, selinux_tun_dev_alloc_security),
7051 LSM_HOOK_INIT(tun_dev_free_security, selinux_tun_dev_free_security),
7052 LSM_HOOK_INIT(tun_dev_create, selinux_tun_dev_create),
7053 LSM_HOOK_INIT(tun_dev_attach_queue, selinux_tun_dev_attach_queue),
7054 LSM_HOOK_INIT(tun_dev_attach, selinux_tun_dev_attach),
7055 LSM_HOOK_INIT(tun_dev_open, selinux_tun_dev_open),
7056#ifdef CONFIG_SECURITY_INFINIBAND
7057 LSM_HOOK_INIT(ib_pkey_access, selinux_ib_pkey_access),
7058 LSM_HOOK_INIT(ib_endport_manage_subnet,
7059 selinux_ib_endport_manage_subnet),
7060 LSM_HOOK_INIT(ib_alloc_security, selinux_ib_alloc_security),
7061 LSM_HOOK_INIT(ib_free_security, selinux_ib_free_security),
7062#endif
7063#ifdef CONFIG_SECURITY_NETWORK_XFRM
7064 LSM_HOOK_INIT(xfrm_policy_alloc_security, selinux_xfrm_policy_alloc),
7065 LSM_HOOK_INIT(xfrm_policy_clone_security, selinux_xfrm_policy_clone),
7066 LSM_HOOK_INIT(xfrm_policy_free_security, selinux_xfrm_policy_free),
7067 LSM_HOOK_INIT(xfrm_policy_delete_security, selinux_xfrm_policy_delete),
7068 LSM_HOOK_INIT(xfrm_state_alloc, selinux_xfrm_state_alloc),
7069 LSM_HOOK_INIT(xfrm_state_alloc_acquire,
7070 selinux_xfrm_state_alloc_acquire),
7071 LSM_HOOK_INIT(xfrm_state_free_security, selinux_xfrm_state_free),
7072 LSM_HOOK_INIT(xfrm_state_delete_security, selinux_xfrm_state_delete),
7073 LSM_HOOK_INIT(xfrm_policy_lookup, selinux_xfrm_policy_lookup),
7074 LSM_HOOK_INIT(xfrm_state_pol_flow_match,
7075 selinux_xfrm_state_pol_flow_match),
7076 LSM_HOOK_INIT(xfrm_decode_session, selinux_xfrm_decode_session),
7077#endif
7078
7079#ifdef CONFIG_KEYS
7080 LSM_HOOK_INIT(key_alloc, selinux_key_alloc),
7081 LSM_HOOK_INIT(key_free, selinux_key_free),
7082 LSM_HOOK_INIT(key_permission, selinux_key_permission),
7083 LSM_HOOK_INIT(key_getsecurity, selinux_key_getsecurity),
7084#endif
7085
7086#ifdef CONFIG_AUDIT
7087 LSM_HOOK_INIT(audit_rule_init, selinux_audit_rule_init),
7088 LSM_HOOK_INIT(audit_rule_known, selinux_audit_rule_known),
7089 LSM_HOOK_INIT(audit_rule_match, selinux_audit_rule_match),
7090 LSM_HOOK_INIT(audit_rule_free, selinux_audit_rule_free),
7091#endif
7092
7093#ifdef CONFIG_BPF_SYSCALL
7094 LSM_HOOK_INIT(bpf, selinux_bpf),
7095 LSM_HOOK_INIT(bpf_map, selinux_bpf_map),
7096 LSM_HOOK_INIT(bpf_prog, selinux_bpf_prog),
7097 LSM_HOOK_INIT(bpf_map_alloc_security, selinux_bpf_map_alloc),
7098 LSM_HOOK_INIT(bpf_prog_alloc_security, selinux_bpf_prog_alloc),
7099 LSM_HOOK_INIT(bpf_map_free_security, selinux_bpf_map_free),
7100 LSM_HOOK_INIT(bpf_prog_free_security, selinux_bpf_prog_free),
7101#endif
7102};
7103
7104static __init int selinux_init(void)
7105{
7106 if (!security_module_enable("selinux")) {
7107 selinux_enabled = 0;
7108 return 0;
7109 }
7110
7111 if (!selinux_enabled) {
7112 printk(KERN_INFO "SELinux: Disabled at boot.\n");
7113 return 0;
7114 }
7115
7116 printk(KERN_INFO "SELinux: Initializing.\n");
7117
7118 memset(&selinux_state, 0, sizeof(selinux_state));
7119 enforcing_set(&selinux_state, selinux_enforcing_boot);
7120 selinux_state.checkreqprot = selinux_checkreqprot_boot;
7121 selinux_ss_init(&selinux_state.ss);
7122 selinux_avc_init(&selinux_state.avc);
7123
7124 /* Set the security state for the initial task. */
7125 cred_init_security();
7126
7127 default_noexec = !(VM_DATA_DEFAULT_FLAGS & VM_EXEC);
7128
7129 sel_inode_cache = kmem_cache_create("selinux_inode_security",
7130 sizeof(struct inode_security_struct),
7131 0, SLAB_PANIC, NULL);
7132 file_security_cache = kmem_cache_create("selinux_file_security",
7133 sizeof(struct file_security_struct),
7134 0, SLAB_PANIC, NULL);
7135 avc_init();
7136
7137 avtab_cache_init();
7138
7139 ebitmap_cache_init();
7140
7141 hashtab_cache_init();
7142
7143 security_add_hooks(selinux_hooks, ARRAY_SIZE(selinux_hooks), "selinux");
7144
7145 if (avc_add_callback(selinux_netcache_avc_callback, AVC_CALLBACK_RESET))
7146 panic("SELinux: Unable to register AVC netcache callback\n");
7147
7148 if (avc_add_callback(selinux_lsm_notifier_avc_callback, AVC_CALLBACK_RESET))
7149 panic("SELinux: Unable to register AVC LSM notifier callback\n");
7150
7151 if (selinux_enforcing_boot)
7152 printk(KERN_DEBUG "SELinux: Starting in enforcing mode\n");
7153 else
7154 printk(KERN_DEBUG "SELinux: Starting in permissive mode\n");
7155
7156 return 0;
7157}
7158
7159static void delayed_superblock_init(struct super_block *sb, void *unused)
7160{
7161 superblock_doinit(sb, NULL);
7162}
7163
7164void selinux_complete_init(void)
7165{
7166 printk(KERN_DEBUG "SELinux: Completing initialization.\n");
7167
7168 /* Set up any superblocks initialized prior to the policy load. */
7169 printk(KERN_DEBUG "SELinux: Setting up existing superblocks.\n");
7170 iterate_supers(delayed_superblock_init, NULL);
7171}
7172
7173/* SELinux requires early initialization in order to label
7174 all processes and objects when they are created. */
7175security_initcall(selinux_init);
7176
7177#if defined(CONFIG_NETFILTER)
7178
7179static const struct nf_hook_ops selinux_nf_ops[] = {
7180 {
7181 .hook = selinux_ipv4_postroute,
7182 .pf = NFPROTO_IPV4,
7183 .hooknum = NF_INET_POST_ROUTING,
7184 .priority = NF_IP_PRI_SELINUX_LAST,
7185 },
7186 {
7187 .hook = selinux_ipv4_forward,
7188 .pf = NFPROTO_IPV4,
7189 .hooknum = NF_INET_FORWARD,
7190 .priority = NF_IP_PRI_SELINUX_FIRST,
7191 },
7192 {
7193 .hook = selinux_ipv4_output,
7194 .pf = NFPROTO_IPV4,
7195 .hooknum = NF_INET_LOCAL_OUT,
7196 .priority = NF_IP_PRI_SELINUX_FIRST,
7197 },
7198#if IS_ENABLED(CONFIG_IPV6)
7199 {
7200 .hook = selinux_ipv6_postroute,
7201 .pf = NFPROTO_IPV6,
7202 .hooknum = NF_INET_POST_ROUTING,
7203 .priority = NF_IP6_PRI_SELINUX_LAST,
7204 },
7205 {
7206 .hook = selinux_ipv6_forward,
7207 .pf = NFPROTO_IPV6,
7208 .hooknum = NF_INET_FORWARD,
7209 .priority = NF_IP6_PRI_SELINUX_FIRST,
7210 },
7211 {
7212 .hook = selinux_ipv6_output,
7213 .pf = NFPROTO_IPV6,
7214 .hooknum = NF_INET_LOCAL_OUT,
7215 .priority = NF_IP6_PRI_SELINUX_FIRST,
7216 },
7217#endif /* IPV6 */
7218};
7219
7220static int __net_init selinux_nf_register(struct net *net)
7221{
7222 return nf_register_net_hooks(net, selinux_nf_ops,
7223 ARRAY_SIZE(selinux_nf_ops));
7224}
7225
7226static void __net_exit selinux_nf_unregister(struct net *net)
7227{
7228 nf_unregister_net_hooks(net, selinux_nf_ops,
7229 ARRAY_SIZE(selinux_nf_ops));
7230}
7231
7232static struct pernet_operations selinux_net_ops = {
7233 .init = selinux_nf_register,
7234 .exit = selinux_nf_unregister,
7235};
7236
7237static int __init selinux_nf_ip_init(void)
7238{
7239 int err;
7240
7241 if (!selinux_enabled)
7242 return 0;
7243
7244 printk(KERN_DEBUG "SELinux: Registering netfilter hooks\n");
7245
7246 err = register_pernet_subsys(&selinux_net_ops);
7247 if (err)
7248 panic("SELinux: register_pernet_subsys: error %d\n", err);
7249
7250 return 0;
7251}
7252__initcall(selinux_nf_ip_init);
7253
7254#ifdef CONFIG_SECURITY_SELINUX_DISABLE
7255static void selinux_nf_ip_exit(void)
7256{
7257 printk(KERN_DEBUG "SELinux: Unregistering netfilter hooks\n");
7258
7259 unregister_pernet_subsys(&selinux_net_ops);
7260}
7261#endif
7262
7263#else /* CONFIG_NETFILTER */
7264
7265#ifdef CONFIG_SECURITY_SELINUX_DISABLE
7266#define selinux_nf_ip_exit()
7267#endif
7268
7269#endif /* CONFIG_NETFILTER */
7270
7271#ifdef CONFIG_SECURITY_SELINUX_DISABLE
7272int selinux_disable(struct selinux_state *state)
7273{
7274 if (state->initialized) {
7275 /* Not permitted after initial policy load. */
7276 return -EINVAL;
7277 }
7278
7279 if (state->disabled) {
7280 /* Only do this once. */
7281 return -EINVAL;
7282 }
7283
7284 state->disabled = 1;
7285
7286 printk(KERN_INFO "SELinux: Disabled at runtime.\n");
7287
7288 selinux_enabled = 0;
7289
7290 security_delete_hooks(selinux_hooks, ARRAY_SIZE(selinux_hooks));
7291
7292 /* Try to destroy the avc node cache */
7293 avc_disable();
7294
7295 /* Unregister netfilter hooks. */
7296 selinux_nf_ip_exit();
7297
7298 /* Unregister selinuxfs. */
7299 exit_sel_fs();
7300
7301 return 0;
7302}
7303#endif
1/*
2 * NSA Security-Enhanced Linux (SELinux) security module
3 *
4 * This file contains the SELinux hook function implementations.
5 *
6 * Authors: Stephen Smalley, <sds@epoch.ncsc.mil>
7 * Chris Vance, <cvance@nai.com>
8 * Wayne Salamon, <wsalamon@nai.com>
9 * James Morris <jmorris@redhat.com>
10 *
11 * Copyright (C) 2001,2002 Networks Associates Technology, Inc.
12 * Copyright (C) 2003-2008 Red Hat, Inc., James Morris <jmorris@redhat.com>
13 * Eric Paris <eparis@redhat.com>
14 * Copyright (C) 2004-2005 Trusted Computer Solutions, Inc.
15 * <dgoeddel@trustedcs.com>
16 * Copyright (C) 2006, 2007, 2009 Hewlett-Packard Development Company, L.P.
17 * Paul Moore <paul@paul-moore.com>
18 * Copyright (C) 2007 Hitachi Software Engineering Co., Ltd.
19 * Yuichi Nakamura <ynakam@hitachisoft.jp>
20 *
21 * This program is free software; you can redistribute it and/or modify
22 * it under the terms of the GNU General Public License version 2,
23 * as published by the Free Software Foundation.
24 */
25
26#include <linux/init.h>
27#include <linux/kd.h>
28#include <linux/kernel.h>
29#include <linux/tracehook.h>
30#include <linux/errno.h>
31#include <linux/sched.h>
32#include <linux/lsm_hooks.h>
33#include <linux/xattr.h>
34#include <linux/capability.h>
35#include <linux/unistd.h>
36#include <linux/mm.h>
37#include <linux/mman.h>
38#include <linux/slab.h>
39#include <linux/pagemap.h>
40#include <linux/proc_fs.h>
41#include <linux/swap.h>
42#include <linux/spinlock.h>
43#include <linux/syscalls.h>
44#include <linux/dcache.h>
45#include <linux/file.h>
46#include <linux/fdtable.h>
47#include <linux/namei.h>
48#include <linux/mount.h>
49#include <linux/netfilter_ipv4.h>
50#include <linux/netfilter_ipv6.h>
51#include <linux/tty.h>
52#include <net/icmp.h>
53#include <net/ip.h> /* for local_port_range[] */
54#include <net/tcp.h> /* struct or_callable used in sock_rcv_skb */
55#include <net/inet_connection_sock.h>
56#include <net/net_namespace.h>
57#include <net/netlabel.h>
58#include <linux/uaccess.h>
59#include <asm/ioctls.h>
60#include <linux/atomic.h>
61#include <linux/bitops.h>
62#include <linux/interrupt.h>
63#include <linux/netdevice.h> /* for network interface checks */
64#include <net/netlink.h>
65#include <linux/tcp.h>
66#include <linux/udp.h>
67#include <linux/dccp.h>
68#include <linux/quota.h>
69#include <linux/un.h> /* for Unix socket types */
70#include <net/af_unix.h> /* for Unix socket types */
71#include <linux/parser.h>
72#include <linux/nfs_mount.h>
73#include <net/ipv6.h>
74#include <linux/hugetlb.h>
75#include <linux/personality.h>
76#include <linux/audit.h>
77#include <linux/string.h>
78#include <linux/selinux.h>
79#include <linux/mutex.h>
80#include <linux/posix-timers.h>
81#include <linux/syslog.h>
82#include <linux/user_namespace.h>
83#include <linux/export.h>
84#include <linux/msg.h>
85#include <linux/shm.h>
86
87#include "avc.h"
88#include "objsec.h"
89#include "netif.h"
90#include "netnode.h"
91#include "netport.h"
92#include "xfrm.h"
93#include "netlabel.h"
94#include "audit.h"
95#include "avc_ss.h"
96
97/* SECMARK reference count */
98static atomic_t selinux_secmark_refcount = ATOMIC_INIT(0);
99
100#ifdef CONFIG_SECURITY_SELINUX_DEVELOP
101int selinux_enforcing;
102
103static int __init enforcing_setup(char *str)
104{
105 unsigned long enforcing;
106 if (!kstrtoul(str, 0, &enforcing))
107 selinux_enforcing = enforcing ? 1 : 0;
108 return 1;
109}
110__setup("enforcing=", enforcing_setup);
111#endif
112
113#ifdef CONFIG_SECURITY_SELINUX_BOOTPARAM
114int selinux_enabled = CONFIG_SECURITY_SELINUX_BOOTPARAM_VALUE;
115
116static int __init selinux_enabled_setup(char *str)
117{
118 unsigned long enabled;
119 if (!kstrtoul(str, 0, &enabled))
120 selinux_enabled = enabled ? 1 : 0;
121 return 1;
122}
123__setup("selinux=", selinux_enabled_setup);
124#else
125int selinux_enabled = 1;
126#endif
127
128static struct kmem_cache *sel_inode_cache;
129static struct kmem_cache *file_security_cache;
130
131/**
132 * selinux_secmark_enabled - Check to see if SECMARK is currently enabled
133 *
134 * Description:
135 * This function checks the SECMARK reference counter to see if any SECMARK
136 * targets are currently configured, if the reference counter is greater than
137 * zero SECMARK is considered to be enabled. Returns true (1) if SECMARK is
138 * enabled, false (0) if SECMARK is disabled. If the always_check_network
139 * policy capability is enabled, SECMARK is always considered enabled.
140 *
141 */
142static int selinux_secmark_enabled(void)
143{
144 return (selinux_policycap_alwaysnetwork || atomic_read(&selinux_secmark_refcount));
145}
146
147/**
148 * selinux_peerlbl_enabled - Check to see if peer labeling is currently enabled
149 *
150 * Description:
151 * This function checks if NetLabel or labeled IPSEC is enabled. Returns true
152 * (1) if any are enabled or false (0) if neither are enabled. If the
153 * always_check_network policy capability is enabled, peer labeling
154 * is always considered enabled.
155 *
156 */
157static int selinux_peerlbl_enabled(void)
158{
159 return (selinux_policycap_alwaysnetwork || netlbl_enabled() || selinux_xfrm_enabled());
160}
161
162static int selinux_netcache_avc_callback(u32 event)
163{
164 if (event == AVC_CALLBACK_RESET) {
165 sel_netif_flush();
166 sel_netnode_flush();
167 sel_netport_flush();
168 synchronize_net();
169 }
170 return 0;
171}
172
173/*
174 * initialise the security for the init task
175 */
176static void cred_init_security(void)
177{
178 struct cred *cred = (struct cred *) current->real_cred;
179 struct task_security_struct *tsec;
180
181 tsec = kzalloc(sizeof(struct task_security_struct), GFP_KERNEL);
182 if (!tsec)
183 panic("SELinux: Failed to initialize initial task.\n");
184
185 tsec->osid = tsec->sid = SECINITSID_KERNEL;
186 cred->security = tsec;
187}
188
189/*
190 * get the security ID of a set of credentials
191 */
192static inline u32 cred_sid(const struct cred *cred)
193{
194 const struct task_security_struct *tsec;
195
196 tsec = cred->security;
197 return tsec->sid;
198}
199
200/*
201 * get the objective security ID of a task
202 */
203static inline u32 task_sid(const struct task_struct *task)
204{
205 u32 sid;
206
207 rcu_read_lock();
208 sid = cred_sid(__task_cred(task));
209 rcu_read_unlock();
210 return sid;
211}
212
213/*
214 * get the subjective security ID of the current task
215 */
216static inline u32 current_sid(void)
217{
218 const struct task_security_struct *tsec = current_security();
219
220 return tsec->sid;
221}
222
223/* Allocate and free functions for each kind of security blob. */
224
225static int inode_alloc_security(struct inode *inode)
226{
227 struct inode_security_struct *isec;
228 u32 sid = current_sid();
229
230 isec = kmem_cache_zalloc(sel_inode_cache, GFP_NOFS);
231 if (!isec)
232 return -ENOMEM;
233
234 spin_lock_init(&isec->lock);
235 INIT_LIST_HEAD(&isec->list);
236 isec->inode = inode;
237 isec->sid = SECINITSID_UNLABELED;
238 isec->sclass = SECCLASS_FILE;
239 isec->task_sid = sid;
240 isec->initialized = LABEL_INVALID;
241 inode->i_security = isec;
242
243 return 0;
244}
245
246static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dentry);
247
248/*
249 * Try reloading inode security labels that have been marked as invalid. The
250 * @may_sleep parameter indicates when sleeping and thus reloading labels is
251 * allowed; when set to false, returns -ECHILD when the label is
252 * invalid. The @opt_dentry parameter should be set to a dentry of the inode;
253 * when no dentry is available, set it to NULL instead.
254 */
255static int __inode_security_revalidate(struct inode *inode,
256 struct dentry *opt_dentry,
257 bool may_sleep)
258{
259 struct inode_security_struct *isec = inode->i_security;
260
261 might_sleep_if(may_sleep);
262
263 if (ss_initialized && isec->initialized != LABEL_INITIALIZED) {
264 if (!may_sleep)
265 return -ECHILD;
266
267 /*
268 * Try reloading the inode security label. This will fail if
269 * @opt_dentry is NULL and no dentry for this inode can be
270 * found; in that case, continue using the old label.
271 */
272 inode_doinit_with_dentry(inode, opt_dentry);
273 }
274 return 0;
275}
276
277static struct inode_security_struct *inode_security_novalidate(struct inode *inode)
278{
279 return inode->i_security;
280}
281
282static struct inode_security_struct *inode_security_rcu(struct inode *inode, bool rcu)
283{
284 int error;
285
286 error = __inode_security_revalidate(inode, NULL, !rcu);
287 if (error)
288 return ERR_PTR(error);
289 return inode->i_security;
290}
291
292/*
293 * Get the security label of an inode.
294 */
295static struct inode_security_struct *inode_security(struct inode *inode)
296{
297 __inode_security_revalidate(inode, NULL, true);
298 return inode->i_security;
299}
300
301static struct inode_security_struct *backing_inode_security_novalidate(struct dentry *dentry)
302{
303 struct inode *inode = d_backing_inode(dentry);
304
305 return inode->i_security;
306}
307
308/*
309 * Get the security label of a dentry's backing inode.
310 */
311static struct inode_security_struct *backing_inode_security(struct dentry *dentry)
312{
313 struct inode *inode = d_backing_inode(dentry);
314
315 __inode_security_revalidate(inode, dentry, true);
316 return inode->i_security;
317}
318
319static void inode_free_rcu(struct rcu_head *head)
320{
321 struct inode_security_struct *isec;
322
323 isec = container_of(head, struct inode_security_struct, rcu);
324 kmem_cache_free(sel_inode_cache, isec);
325}
326
327static void inode_free_security(struct inode *inode)
328{
329 struct inode_security_struct *isec = inode->i_security;
330 struct superblock_security_struct *sbsec = inode->i_sb->s_security;
331
332 /*
333 * As not all inode security structures are in a list, we check for
334 * empty list outside of the lock to make sure that we won't waste
335 * time taking a lock doing nothing.
336 *
337 * The list_del_init() function can be safely called more than once.
338 * It should not be possible for this function to be called with
339 * concurrent list_add(), but for better safety against future changes
340 * in the code, we use list_empty_careful() here.
341 */
342 if (!list_empty_careful(&isec->list)) {
343 spin_lock(&sbsec->isec_lock);
344 list_del_init(&isec->list);
345 spin_unlock(&sbsec->isec_lock);
346 }
347
348 /*
349 * The inode may still be referenced in a path walk and
350 * a call to selinux_inode_permission() can be made
351 * after inode_free_security() is called. Ideally, the VFS
352 * wouldn't do this, but fixing that is a much harder
353 * job. For now, simply free the i_security via RCU, and
354 * leave the current inode->i_security pointer intact.
355 * The inode will be freed after the RCU grace period too.
356 */
357 call_rcu(&isec->rcu, inode_free_rcu);
358}
359
360static int file_alloc_security(struct file *file)
361{
362 struct file_security_struct *fsec;
363 u32 sid = current_sid();
364
365 fsec = kmem_cache_zalloc(file_security_cache, GFP_KERNEL);
366 if (!fsec)
367 return -ENOMEM;
368
369 fsec->sid = sid;
370 fsec->fown_sid = sid;
371 file->f_security = fsec;
372
373 return 0;
374}
375
376static void file_free_security(struct file *file)
377{
378 struct file_security_struct *fsec = file->f_security;
379 file->f_security = NULL;
380 kmem_cache_free(file_security_cache, fsec);
381}
382
383static int superblock_alloc_security(struct super_block *sb)
384{
385 struct superblock_security_struct *sbsec;
386
387 sbsec = kzalloc(sizeof(struct superblock_security_struct), GFP_KERNEL);
388 if (!sbsec)
389 return -ENOMEM;
390
391 mutex_init(&sbsec->lock);
392 INIT_LIST_HEAD(&sbsec->isec_head);
393 spin_lock_init(&sbsec->isec_lock);
394 sbsec->sb = sb;
395 sbsec->sid = SECINITSID_UNLABELED;
396 sbsec->def_sid = SECINITSID_FILE;
397 sbsec->mntpoint_sid = SECINITSID_UNLABELED;
398 sb->s_security = sbsec;
399
400 return 0;
401}
402
403static void superblock_free_security(struct super_block *sb)
404{
405 struct superblock_security_struct *sbsec = sb->s_security;
406 sb->s_security = NULL;
407 kfree(sbsec);
408}
409
410/* The file system's label must be initialized prior to use. */
411
412static const char *labeling_behaviors[7] = {
413 "uses xattr",
414 "uses transition SIDs",
415 "uses task SIDs",
416 "uses genfs_contexts",
417 "not configured for labeling",
418 "uses mountpoint labeling",
419 "uses native labeling",
420};
421
422static inline int inode_doinit(struct inode *inode)
423{
424 return inode_doinit_with_dentry(inode, NULL);
425}
426
427enum {
428 Opt_error = -1,
429 Opt_context = 1,
430 Opt_fscontext = 2,
431 Opt_defcontext = 3,
432 Opt_rootcontext = 4,
433 Opt_labelsupport = 5,
434 Opt_nextmntopt = 6,
435};
436
437#define NUM_SEL_MNT_OPTS (Opt_nextmntopt - 1)
438
439static const match_table_t tokens = {
440 {Opt_context, CONTEXT_STR "%s"},
441 {Opt_fscontext, FSCONTEXT_STR "%s"},
442 {Opt_defcontext, DEFCONTEXT_STR "%s"},
443 {Opt_rootcontext, ROOTCONTEXT_STR "%s"},
444 {Opt_labelsupport, LABELSUPP_STR},
445 {Opt_error, NULL},
446};
447
448#define SEL_MOUNT_FAIL_MSG "SELinux: duplicate or incompatible mount options\n"
449
450static int may_context_mount_sb_relabel(u32 sid,
451 struct superblock_security_struct *sbsec,
452 const struct cred *cred)
453{
454 const struct task_security_struct *tsec = cred->security;
455 int rc;
456
457 rc = avc_has_perm(tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM,
458 FILESYSTEM__RELABELFROM, NULL);
459 if (rc)
460 return rc;
461
462 rc = avc_has_perm(tsec->sid, sid, SECCLASS_FILESYSTEM,
463 FILESYSTEM__RELABELTO, NULL);
464 return rc;
465}
466
467static int may_context_mount_inode_relabel(u32 sid,
468 struct superblock_security_struct *sbsec,
469 const struct cred *cred)
470{
471 const struct task_security_struct *tsec = cred->security;
472 int rc;
473 rc = avc_has_perm(tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM,
474 FILESYSTEM__RELABELFROM, NULL);
475 if (rc)
476 return rc;
477
478 rc = avc_has_perm(sid, sbsec->sid, SECCLASS_FILESYSTEM,
479 FILESYSTEM__ASSOCIATE, NULL);
480 return rc;
481}
482
483static int selinux_is_sblabel_mnt(struct super_block *sb)
484{
485 struct superblock_security_struct *sbsec = sb->s_security;
486
487 return sbsec->behavior == SECURITY_FS_USE_XATTR ||
488 sbsec->behavior == SECURITY_FS_USE_TRANS ||
489 sbsec->behavior == SECURITY_FS_USE_TASK ||
490 sbsec->behavior == SECURITY_FS_USE_NATIVE ||
491 /* Special handling. Genfs but also in-core setxattr handler */
492 !strcmp(sb->s_type->name, "sysfs") ||
493 !strcmp(sb->s_type->name, "pstore") ||
494 !strcmp(sb->s_type->name, "debugfs") ||
495 !strcmp(sb->s_type->name, "rootfs");
496}
497
498static int sb_finish_set_opts(struct super_block *sb)
499{
500 struct superblock_security_struct *sbsec = sb->s_security;
501 struct dentry *root = sb->s_root;
502 struct inode *root_inode = d_backing_inode(root);
503 int rc = 0;
504
505 if (sbsec->behavior == SECURITY_FS_USE_XATTR) {
506 /* Make sure that the xattr handler exists and that no
507 error other than -ENODATA is returned by getxattr on
508 the root directory. -ENODATA is ok, as this may be
509 the first boot of the SELinux kernel before we have
510 assigned xattr values to the filesystem. */
511 if (!(root_inode->i_opflags & IOP_XATTR)) {
512 printk(KERN_WARNING "SELinux: (dev %s, type %s) has no "
513 "xattr support\n", sb->s_id, sb->s_type->name);
514 rc = -EOPNOTSUPP;
515 goto out;
516 }
517
518 rc = __vfs_getxattr(root, root_inode, XATTR_NAME_SELINUX, NULL, 0);
519 if (rc < 0 && rc != -ENODATA) {
520 if (rc == -EOPNOTSUPP)
521 printk(KERN_WARNING "SELinux: (dev %s, type "
522 "%s) has no security xattr handler\n",
523 sb->s_id, sb->s_type->name);
524 else
525 printk(KERN_WARNING "SELinux: (dev %s, type "
526 "%s) getxattr errno %d\n", sb->s_id,
527 sb->s_type->name, -rc);
528 goto out;
529 }
530 }
531
532 if (sbsec->behavior > ARRAY_SIZE(labeling_behaviors))
533 printk(KERN_ERR "SELinux: initialized (dev %s, type %s), unknown behavior\n",
534 sb->s_id, sb->s_type->name);
535
536 sbsec->flags |= SE_SBINITIALIZED;
537 if (selinux_is_sblabel_mnt(sb))
538 sbsec->flags |= SBLABEL_MNT;
539
540 /* Initialize the root inode. */
541 rc = inode_doinit_with_dentry(root_inode, root);
542
543 /* Initialize any other inodes associated with the superblock, e.g.
544 inodes created prior to initial policy load or inodes created
545 during get_sb by a pseudo filesystem that directly
546 populates itself. */
547 spin_lock(&sbsec->isec_lock);
548next_inode:
549 if (!list_empty(&sbsec->isec_head)) {
550 struct inode_security_struct *isec =
551 list_entry(sbsec->isec_head.next,
552 struct inode_security_struct, list);
553 struct inode *inode = isec->inode;
554 list_del_init(&isec->list);
555 spin_unlock(&sbsec->isec_lock);
556 inode = igrab(inode);
557 if (inode) {
558 if (!IS_PRIVATE(inode))
559 inode_doinit(inode);
560 iput(inode);
561 }
562 spin_lock(&sbsec->isec_lock);
563 goto next_inode;
564 }
565 spin_unlock(&sbsec->isec_lock);
566out:
567 return rc;
568}
569
570/*
571 * This function should allow an FS to ask what it's mount security
572 * options were so it can use those later for submounts, displaying
573 * mount options, or whatever.
574 */
575static int selinux_get_mnt_opts(const struct super_block *sb,
576 struct security_mnt_opts *opts)
577{
578 int rc = 0, i;
579 struct superblock_security_struct *sbsec = sb->s_security;
580 char *context = NULL;
581 u32 len;
582 char tmp;
583
584 security_init_mnt_opts(opts);
585
586 if (!(sbsec->flags & SE_SBINITIALIZED))
587 return -EINVAL;
588
589 if (!ss_initialized)
590 return -EINVAL;
591
592 /* make sure we always check enough bits to cover the mask */
593 BUILD_BUG_ON(SE_MNTMASK >= (1 << NUM_SEL_MNT_OPTS));
594
595 tmp = sbsec->flags & SE_MNTMASK;
596 /* count the number of mount options for this sb */
597 for (i = 0; i < NUM_SEL_MNT_OPTS; i++) {
598 if (tmp & 0x01)
599 opts->num_mnt_opts++;
600 tmp >>= 1;
601 }
602 /* Check if the Label support flag is set */
603 if (sbsec->flags & SBLABEL_MNT)
604 opts->num_mnt_opts++;
605
606 opts->mnt_opts = kcalloc(opts->num_mnt_opts, sizeof(char *), GFP_ATOMIC);
607 if (!opts->mnt_opts) {
608 rc = -ENOMEM;
609 goto out_free;
610 }
611
612 opts->mnt_opts_flags = kcalloc(opts->num_mnt_opts, sizeof(int), GFP_ATOMIC);
613 if (!opts->mnt_opts_flags) {
614 rc = -ENOMEM;
615 goto out_free;
616 }
617
618 i = 0;
619 if (sbsec->flags & FSCONTEXT_MNT) {
620 rc = security_sid_to_context(sbsec->sid, &context, &len);
621 if (rc)
622 goto out_free;
623 opts->mnt_opts[i] = context;
624 opts->mnt_opts_flags[i++] = FSCONTEXT_MNT;
625 }
626 if (sbsec->flags & CONTEXT_MNT) {
627 rc = security_sid_to_context(sbsec->mntpoint_sid, &context, &len);
628 if (rc)
629 goto out_free;
630 opts->mnt_opts[i] = context;
631 opts->mnt_opts_flags[i++] = CONTEXT_MNT;
632 }
633 if (sbsec->flags & DEFCONTEXT_MNT) {
634 rc = security_sid_to_context(sbsec->def_sid, &context, &len);
635 if (rc)
636 goto out_free;
637 opts->mnt_opts[i] = context;
638 opts->mnt_opts_flags[i++] = DEFCONTEXT_MNT;
639 }
640 if (sbsec->flags & ROOTCONTEXT_MNT) {
641 struct dentry *root = sbsec->sb->s_root;
642 struct inode_security_struct *isec = backing_inode_security(root);
643
644 rc = security_sid_to_context(isec->sid, &context, &len);
645 if (rc)
646 goto out_free;
647 opts->mnt_opts[i] = context;
648 opts->mnt_opts_flags[i++] = ROOTCONTEXT_MNT;
649 }
650 if (sbsec->flags & SBLABEL_MNT) {
651 opts->mnt_opts[i] = NULL;
652 opts->mnt_opts_flags[i++] = SBLABEL_MNT;
653 }
654
655 BUG_ON(i != opts->num_mnt_opts);
656
657 return 0;
658
659out_free:
660 security_free_mnt_opts(opts);
661 return rc;
662}
663
664static int bad_option(struct superblock_security_struct *sbsec, char flag,
665 u32 old_sid, u32 new_sid)
666{
667 char mnt_flags = sbsec->flags & SE_MNTMASK;
668
669 /* check if the old mount command had the same options */
670 if (sbsec->flags & SE_SBINITIALIZED)
671 if (!(sbsec->flags & flag) ||
672 (old_sid != new_sid))
673 return 1;
674
675 /* check if we were passed the same options twice,
676 * aka someone passed context=a,context=b
677 */
678 if (!(sbsec->flags & SE_SBINITIALIZED))
679 if (mnt_flags & flag)
680 return 1;
681 return 0;
682}
683
684/*
685 * Allow filesystems with binary mount data to explicitly set mount point
686 * labeling information.
687 */
688static int selinux_set_mnt_opts(struct super_block *sb,
689 struct security_mnt_opts *opts,
690 unsigned long kern_flags,
691 unsigned long *set_kern_flags)
692{
693 const struct cred *cred = current_cred();
694 int rc = 0, i;
695 struct superblock_security_struct *sbsec = sb->s_security;
696 const char *name = sb->s_type->name;
697 struct dentry *root = sbsec->sb->s_root;
698 struct inode_security_struct *root_isec;
699 u32 fscontext_sid = 0, context_sid = 0, rootcontext_sid = 0;
700 u32 defcontext_sid = 0;
701 char **mount_options = opts->mnt_opts;
702 int *flags = opts->mnt_opts_flags;
703 int num_opts = opts->num_mnt_opts;
704
705 mutex_lock(&sbsec->lock);
706
707 if (!ss_initialized) {
708 if (!num_opts) {
709 /* Defer initialization until selinux_complete_init,
710 after the initial policy is loaded and the security
711 server is ready to handle calls. */
712 goto out;
713 }
714 rc = -EINVAL;
715 printk(KERN_WARNING "SELinux: Unable to set superblock options "
716 "before the security server is initialized\n");
717 goto out;
718 }
719 if (kern_flags && !set_kern_flags) {
720 /* Specifying internal flags without providing a place to
721 * place the results is not allowed */
722 rc = -EINVAL;
723 goto out;
724 }
725
726 /*
727 * Binary mount data FS will come through this function twice. Once
728 * from an explicit call and once from the generic calls from the vfs.
729 * Since the generic VFS calls will not contain any security mount data
730 * we need to skip the double mount verification.
731 *
732 * This does open a hole in which we will not notice if the first
733 * mount using this sb set explict options and a second mount using
734 * this sb does not set any security options. (The first options
735 * will be used for both mounts)
736 */
737 if ((sbsec->flags & SE_SBINITIALIZED) && (sb->s_type->fs_flags & FS_BINARY_MOUNTDATA)
738 && (num_opts == 0))
739 goto out;
740
741 root_isec = backing_inode_security_novalidate(root);
742
743 /*
744 * parse the mount options, check if they are valid sids.
745 * also check if someone is trying to mount the same sb more
746 * than once with different security options.
747 */
748 for (i = 0; i < num_opts; i++) {
749 u32 sid;
750
751 if (flags[i] == SBLABEL_MNT)
752 continue;
753 rc = security_context_str_to_sid(mount_options[i], &sid, GFP_KERNEL);
754 if (rc) {
755 printk(KERN_WARNING "SELinux: security_context_str_to_sid"
756 "(%s) failed for (dev %s, type %s) errno=%d\n",
757 mount_options[i], sb->s_id, name, rc);
758 goto out;
759 }
760 switch (flags[i]) {
761 case FSCONTEXT_MNT:
762 fscontext_sid = sid;
763
764 if (bad_option(sbsec, FSCONTEXT_MNT, sbsec->sid,
765 fscontext_sid))
766 goto out_double_mount;
767
768 sbsec->flags |= FSCONTEXT_MNT;
769 break;
770 case CONTEXT_MNT:
771 context_sid = sid;
772
773 if (bad_option(sbsec, CONTEXT_MNT, sbsec->mntpoint_sid,
774 context_sid))
775 goto out_double_mount;
776
777 sbsec->flags |= CONTEXT_MNT;
778 break;
779 case ROOTCONTEXT_MNT:
780 rootcontext_sid = sid;
781
782 if (bad_option(sbsec, ROOTCONTEXT_MNT, root_isec->sid,
783 rootcontext_sid))
784 goto out_double_mount;
785
786 sbsec->flags |= ROOTCONTEXT_MNT;
787
788 break;
789 case DEFCONTEXT_MNT:
790 defcontext_sid = sid;
791
792 if (bad_option(sbsec, DEFCONTEXT_MNT, sbsec->def_sid,
793 defcontext_sid))
794 goto out_double_mount;
795
796 sbsec->flags |= DEFCONTEXT_MNT;
797
798 break;
799 default:
800 rc = -EINVAL;
801 goto out;
802 }
803 }
804
805 if (sbsec->flags & SE_SBINITIALIZED) {
806 /* previously mounted with options, but not on this attempt? */
807 if ((sbsec->flags & SE_MNTMASK) && !num_opts)
808 goto out_double_mount;
809 rc = 0;
810 goto out;
811 }
812
813 if (strcmp(sb->s_type->name, "proc") == 0)
814 sbsec->flags |= SE_SBPROC | SE_SBGENFS;
815
816 if (!strcmp(sb->s_type->name, "debugfs") ||
817 !strcmp(sb->s_type->name, "sysfs") ||
818 !strcmp(sb->s_type->name, "pstore"))
819 sbsec->flags |= SE_SBGENFS;
820
821 if (!sbsec->behavior) {
822 /*
823 * Determine the labeling behavior to use for this
824 * filesystem type.
825 */
826 rc = security_fs_use(sb);
827 if (rc) {
828 printk(KERN_WARNING
829 "%s: security_fs_use(%s) returned %d\n",
830 __func__, sb->s_type->name, rc);
831 goto out;
832 }
833 }
834
835 /*
836 * If this is a user namespace mount, no contexts are allowed
837 * on the command line and security labels must be ignored.
838 */
839 if (sb->s_user_ns != &init_user_ns) {
840 if (context_sid || fscontext_sid || rootcontext_sid ||
841 defcontext_sid) {
842 rc = -EACCES;
843 goto out;
844 }
845 if (sbsec->behavior == SECURITY_FS_USE_XATTR) {
846 sbsec->behavior = SECURITY_FS_USE_MNTPOINT;
847 rc = security_transition_sid(current_sid(), current_sid(),
848 SECCLASS_FILE, NULL,
849 &sbsec->mntpoint_sid);
850 if (rc)
851 goto out;
852 }
853 goto out_set_opts;
854 }
855
856 /* sets the context of the superblock for the fs being mounted. */
857 if (fscontext_sid) {
858 rc = may_context_mount_sb_relabel(fscontext_sid, sbsec, cred);
859 if (rc)
860 goto out;
861
862 sbsec->sid = fscontext_sid;
863 }
864
865 /*
866 * Switch to using mount point labeling behavior.
867 * sets the label used on all file below the mountpoint, and will set
868 * the superblock context if not already set.
869 */
870 if (kern_flags & SECURITY_LSM_NATIVE_LABELS && !context_sid) {
871 sbsec->behavior = SECURITY_FS_USE_NATIVE;
872 *set_kern_flags |= SECURITY_LSM_NATIVE_LABELS;
873 }
874
875 if (context_sid) {
876 if (!fscontext_sid) {
877 rc = may_context_mount_sb_relabel(context_sid, sbsec,
878 cred);
879 if (rc)
880 goto out;
881 sbsec->sid = context_sid;
882 } else {
883 rc = may_context_mount_inode_relabel(context_sid, sbsec,
884 cred);
885 if (rc)
886 goto out;
887 }
888 if (!rootcontext_sid)
889 rootcontext_sid = context_sid;
890
891 sbsec->mntpoint_sid = context_sid;
892 sbsec->behavior = SECURITY_FS_USE_MNTPOINT;
893 }
894
895 if (rootcontext_sid) {
896 rc = may_context_mount_inode_relabel(rootcontext_sid, sbsec,
897 cred);
898 if (rc)
899 goto out;
900
901 root_isec->sid = rootcontext_sid;
902 root_isec->initialized = LABEL_INITIALIZED;
903 }
904
905 if (defcontext_sid) {
906 if (sbsec->behavior != SECURITY_FS_USE_XATTR &&
907 sbsec->behavior != SECURITY_FS_USE_NATIVE) {
908 rc = -EINVAL;
909 printk(KERN_WARNING "SELinux: defcontext option is "
910 "invalid for this filesystem type\n");
911 goto out;
912 }
913
914 if (defcontext_sid != sbsec->def_sid) {
915 rc = may_context_mount_inode_relabel(defcontext_sid,
916 sbsec, cred);
917 if (rc)
918 goto out;
919 }
920
921 sbsec->def_sid = defcontext_sid;
922 }
923
924out_set_opts:
925 rc = sb_finish_set_opts(sb);
926out:
927 mutex_unlock(&sbsec->lock);
928 return rc;
929out_double_mount:
930 rc = -EINVAL;
931 printk(KERN_WARNING "SELinux: mount invalid. Same superblock, different "
932 "security settings for (dev %s, type %s)\n", sb->s_id, name);
933 goto out;
934}
935
936static int selinux_cmp_sb_context(const struct super_block *oldsb,
937 const struct super_block *newsb)
938{
939 struct superblock_security_struct *old = oldsb->s_security;
940 struct superblock_security_struct *new = newsb->s_security;
941 char oldflags = old->flags & SE_MNTMASK;
942 char newflags = new->flags & SE_MNTMASK;
943
944 if (oldflags != newflags)
945 goto mismatch;
946 if ((oldflags & FSCONTEXT_MNT) && old->sid != new->sid)
947 goto mismatch;
948 if ((oldflags & CONTEXT_MNT) && old->mntpoint_sid != new->mntpoint_sid)
949 goto mismatch;
950 if ((oldflags & DEFCONTEXT_MNT) && old->def_sid != new->def_sid)
951 goto mismatch;
952 if (oldflags & ROOTCONTEXT_MNT) {
953 struct inode_security_struct *oldroot = backing_inode_security(oldsb->s_root);
954 struct inode_security_struct *newroot = backing_inode_security(newsb->s_root);
955 if (oldroot->sid != newroot->sid)
956 goto mismatch;
957 }
958 return 0;
959mismatch:
960 printk(KERN_WARNING "SELinux: mount invalid. Same superblock, "
961 "different security settings for (dev %s, "
962 "type %s)\n", newsb->s_id, newsb->s_type->name);
963 return -EBUSY;
964}
965
966static int selinux_sb_clone_mnt_opts(const struct super_block *oldsb,
967 struct super_block *newsb)
968{
969 const struct superblock_security_struct *oldsbsec = oldsb->s_security;
970 struct superblock_security_struct *newsbsec = newsb->s_security;
971
972 int set_fscontext = (oldsbsec->flags & FSCONTEXT_MNT);
973 int set_context = (oldsbsec->flags & CONTEXT_MNT);
974 int set_rootcontext = (oldsbsec->flags & ROOTCONTEXT_MNT);
975
976 /*
977 * if the parent was able to be mounted it clearly had no special lsm
978 * mount options. thus we can safely deal with this superblock later
979 */
980 if (!ss_initialized)
981 return 0;
982
983 /* how can we clone if the old one wasn't set up?? */
984 BUG_ON(!(oldsbsec->flags & SE_SBINITIALIZED));
985
986 /* if fs is reusing a sb, make sure that the contexts match */
987 if (newsbsec->flags & SE_SBINITIALIZED)
988 return selinux_cmp_sb_context(oldsb, newsb);
989
990 mutex_lock(&newsbsec->lock);
991
992 newsbsec->flags = oldsbsec->flags;
993
994 newsbsec->sid = oldsbsec->sid;
995 newsbsec->def_sid = oldsbsec->def_sid;
996 newsbsec->behavior = oldsbsec->behavior;
997
998 if (set_context) {
999 u32 sid = oldsbsec->mntpoint_sid;
1000
1001 if (!set_fscontext)
1002 newsbsec->sid = sid;
1003 if (!set_rootcontext) {
1004 struct inode_security_struct *newisec = backing_inode_security(newsb->s_root);
1005 newisec->sid = sid;
1006 }
1007 newsbsec->mntpoint_sid = sid;
1008 }
1009 if (set_rootcontext) {
1010 const struct inode_security_struct *oldisec = backing_inode_security(oldsb->s_root);
1011 struct inode_security_struct *newisec = backing_inode_security(newsb->s_root);
1012
1013 newisec->sid = oldisec->sid;
1014 }
1015
1016 sb_finish_set_opts(newsb);
1017 mutex_unlock(&newsbsec->lock);
1018 return 0;
1019}
1020
1021static int selinux_parse_opts_str(char *options,
1022 struct security_mnt_opts *opts)
1023{
1024 char *p;
1025 char *context = NULL, *defcontext = NULL;
1026 char *fscontext = NULL, *rootcontext = NULL;
1027 int rc, num_mnt_opts = 0;
1028
1029 opts->num_mnt_opts = 0;
1030
1031 /* Standard string-based options. */
1032 while ((p = strsep(&options, "|")) != NULL) {
1033 int token;
1034 substring_t args[MAX_OPT_ARGS];
1035
1036 if (!*p)
1037 continue;
1038
1039 token = match_token(p, tokens, args);
1040
1041 switch (token) {
1042 case Opt_context:
1043 if (context || defcontext) {
1044 rc = -EINVAL;
1045 printk(KERN_WARNING SEL_MOUNT_FAIL_MSG);
1046 goto out_err;
1047 }
1048 context = match_strdup(&args[0]);
1049 if (!context) {
1050 rc = -ENOMEM;
1051 goto out_err;
1052 }
1053 break;
1054
1055 case Opt_fscontext:
1056 if (fscontext) {
1057 rc = -EINVAL;
1058 printk(KERN_WARNING SEL_MOUNT_FAIL_MSG);
1059 goto out_err;
1060 }
1061 fscontext = match_strdup(&args[0]);
1062 if (!fscontext) {
1063 rc = -ENOMEM;
1064 goto out_err;
1065 }
1066 break;
1067
1068 case Opt_rootcontext:
1069 if (rootcontext) {
1070 rc = -EINVAL;
1071 printk(KERN_WARNING SEL_MOUNT_FAIL_MSG);
1072 goto out_err;
1073 }
1074 rootcontext = match_strdup(&args[0]);
1075 if (!rootcontext) {
1076 rc = -ENOMEM;
1077 goto out_err;
1078 }
1079 break;
1080
1081 case Opt_defcontext:
1082 if (context || defcontext) {
1083 rc = -EINVAL;
1084 printk(KERN_WARNING SEL_MOUNT_FAIL_MSG);
1085 goto out_err;
1086 }
1087 defcontext = match_strdup(&args[0]);
1088 if (!defcontext) {
1089 rc = -ENOMEM;
1090 goto out_err;
1091 }
1092 break;
1093 case Opt_labelsupport:
1094 break;
1095 default:
1096 rc = -EINVAL;
1097 printk(KERN_WARNING "SELinux: unknown mount option\n");
1098 goto out_err;
1099
1100 }
1101 }
1102
1103 rc = -ENOMEM;
1104 opts->mnt_opts = kcalloc(NUM_SEL_MNT_OPTS, sizeof(char *), GFP_KERNEL);
1105 if (!opts->mnt_opts)
1106 goto out_err;
1107
1108 opts->mnt_opts_flags = kcalloc(NUM_SEL_MNT_OPTS, sizeof(int),
1109 GFP_KERNEL);
1110 if (!opts->mnt_opts_flags) {
1111 kfree(opts->mnt_opts);
1112 goto out_err;
1113 }
1114
1115 if (fscontext) {
1116 opts->mnt_opts[num_mnt_opts] = fscontext;
1117 opts->mnt_opts_flags[num_mnt_opts++] = FSCONTEXT_MNT;
1118 }
1119 if (context) {
1120 opts->mnt_opts[num_mnt_opts] = context;
1121 opts->mnt_opts_flags[num_mnt_opts++] = CONTEXT_MNT;
1122 }
1123 if (rootcontext) {
1124 opts->mnt_opts[num_mnt_opts] = rootcontext;
1125 opts->mnt_opts_flags[num_mnt_opts++] = ROOTCONTEXT_MNT;
1126 }
1127 if (defcontext) {
1128 opts->mnt_opts[num_mnt_opts] = defcontext;
1129 opts->mnt_opts_flags[num_mnt_opts++] = DEFCONTEXT_MNT;
1130 }
1131
1132 opts->num_mnt_opts = num_mnt_opts;
1133 return 0;
1134
1135out_err:
1136 kfree(context);
1137 kfree(defcontext);
1138 kfree(fscontext);
1139 kfree(rootcontext);
1140 return rc;
1141}
1142/*
1143 * string mount options parsing and call set the sbsec
1144 */
1145static int superblock_doinit(struct super_block *sb, void *data)
1146{
1147 int rc = 0;
1148 char *options = data;
1149 struct security_mnt_opts opts;
1150
1151 security_init_mnt_opts(&opts);
1152
1153 if (!data)
1154 goto out;
1155
1156 BUG_ON(sb->s_type->fs_flags & FS_BINARY_MOUNTDATA);
1157
1158 rc = selinux_parse_opts_str(options, &opts);
1159 if (rc)
1160 goto out_err;
1161
1162out:
1163 rc = selinux_set_mnt_opts(sb, &opts, 0, NULL);
1164
1165out_err:
1166 security_free_mnt_opts(&opts);
1167 return rc;
1168}
1169
1170static void selinux_write_opts(struct seq_file *m,
1171 struct security_mnt_opts *opts)
1172{
1173 int i;
1174 char *prefix;
1175
1176 for (i = 0; i < opts->num_mnt_opts; i++) {
1177 char *has_comma;
1178
1179 if (opts->mnt_opts[i])
1180 has_comma = strchr(opts->mnt_opts[i], ',');
1181 else
1182 has_comma = NULL;
1183
1184 switch (opts->mnt_opts_flags[i]) {
1185 case CONTEXT_MNT:
1186 prefix = CONTEXT_STR;
1187 break;
1188 case FSCONTEXT_MNT:
1189 prefix = FSCONTEXT_STR;
1190 break;
1191 case ROOTCONTEXT_MNT:
1192 prefix = ROOTCONTEXT_STR;
1193 break;
1194 case DEFCONTEXT_MNT:
1195 prefix = DEFCONTEXT_STR;
1196 break;
1197 case SBLABEL_MNT:
1198 seq_putc(m, ',');
1199 seq_puts(m, LABELSUPP_STR);
1200 continue;
1201 default:
1202 BUG();
1203 return;
1204 };
1205 /* we need a comma before each option */
1206 seq_putc(m, ',');
1207 seq_puts(m, prefix);
1208 if (has_comma)
1209 seq_putc(m, '\"');
1210 seq_escape(m, opts->mnt_opts[i], "\"\n\\");
1211 if (has_comma)
1212 seq_putc(m, '\"');
1213 }
1214}
1215
1216static int selinux_sb_show_options(struct seq_file *m, struct super_block *sb)
1217{
1218 struct security_mnt_opts opts;
1219 int rc;
1220
1221 rc = selinux_get_mnt_opts(sb, &opts);
1222 if (rc) {
1223 /* before policy load we may get EINVAL, don't show anything */
1224 if (rc == -EINVAL)
1225 rc = 0;
1226 return rc;
1227 }
1228
1229 selinux_write_opts(m, &opts);
1230
1231 security_free_mnt_opts(&opts);
1232
1233 return rc;
1234}
1235
1236static inline u16 inode_mode_to_security_class(umode_t mode)
1237{
1238 switch (mode & S_IFMT) {
1239 case S_IFSOCK:
1240 return SECCLASS_SOCK_FILE;
1241 case S_IFLNK:
1242 return SECCLASS_LNK_FILE;
1243 case S_IFREG:
1244 return SECCLASS_FILE;
1245 case S_IFBLK:
1246 return SECCLASS_BLK_FILE;
1247 case S_IFDIR:
1248 return SECCLASS_DIR;
1249 case S_IFCHR:
1250 return SECCLASS_CHR_FILE;
1251 case S_IFIFO:
1252 return SECCLASS_FIFO_FILE;
1253
1254 }
1255
1256 return SECCLASS_FILE;
1257}
1258
1259static inline int default_protocol_stream(int protocol)
1260{
1261 return (protocol == IPPROTO_IP || protocol == IPPROTO_TCP);
1262}
1263
1264static inline int default_protocol_dgram(int protocol)
1265{
1266 return (protocol == IPPROTO_IP || protocol == IPPROTO_UDP);
1267}
1268
1269static inline u16 socket_type_to_security_class(int family, int type, int protocol)
1270{
1271 switch (family) {
1272 case PF_UNIX:
1273 switch (type) {
1274 case SOCK_STREAM:
1275 case SOCK_SEQPACKET:
1276 return SECCLASS_UNIX_STREAM_SOCKET;
1277 case SOCK_DGRAM:
1278 return SECCLASS_UNIX_DGRAM_SOCKET;
1279 }
1280 break;
1281 case PF_INET:
1282 case PF_INET6:
1283 switch (type) {
1284 case SOCK_STREAM:
1285 if (default_protocol_stream(protocol))
1286 return SECCLASS_TCP_SOCKET;
1287 else
1288 return SECCLASS_RAWIP_SOCKET;
1289 case SOCK_DGRAM:
1290 if (default_protocol_dgram(protocol))
1291 return SECCLASS_UDP_SOCKET;
1292 else
1293 return SECCLASS_RAWIP_SOCKET;
1294 case SOCK_DCCP:
1295 return SECCLASS_DCCP_SOCKET;
1296 default:
1297 return SECCLASS_RAWIP_SOCKET;
1298 }
1299 break;
1300 case PF_NETLINK:
1301 switch (protocol) {
1302 case NETLINK_ROUTE:
1303 return SECCLASS_NETLINK_ROUTE_SOCKET;
1304 case NETLINK_SOCK_DIAG:
1305 return SECCLASS_NETLINK_TCPDIAG_SOCKET;
1306 case NETLINK_NFLOG:
1307 return SECCLASS_NETLINK_NFLOG_SOCKET;
1308 case NETLINK_XFRM:
1309 return SECCLASS_NETLINK_XFRM_SOCKET;
1310 case NETLINK_SELINUX:
1311 return SECCLASS_NETLINK_SELINUX_SOCKET;
1312 case NETLINK_ISCSI:
1313 return SECCLASS_NETLINK_ISCSI_SOCKET;
1314 case NETLINK_AUDIT:
1315 return SECCLASS_NETLINK_AUDIT_SOCKET;
1316 case NETLINK_FIB_LOOKUP:
1317 return SECCLASS_NETLINK_FIB_LOOKUP_SOCKET;
1318 case NETLINK_CONNECTOR:
1319 return SECCLASS_NETLINK_CONNECTOR_SOCKET;
1320 case NETLINK_NETFILTER:
1321 return SECCLASS_NETLINK_NETFILTER_SOCKET;
1322 case NETLINK_DNRTMSG:
1323 return SECCLASS_NETLINK_DNRT_SOCKET;
1324 case NETLINK_KOBJECT_UEVENT:
1325 return SECCLASS_NETLINK_KOBJECT_UEVENT_SOCKET;
1326 case NETLINK_GENERIC:
1327 return SECCLASS_NETLINK_GENERIC_SOCKET;
1328 case NETLINK_SCSITRANSPORT:
1329 return SECCLASS_NETLINK_SCSITRANSPORT_SOCKET;
1330 case NETLINK_RDMA:
1331 return SECCLASS_NETLINK_RDMA_SOCKET;
1332 case NETLINK_CRYPTO:
1333 return SECCLASS_NETLINK_CRYPTO_SOCKET;
1334 default:
1335 return SECCLASS_NETLINK_SOCKET;
1336 }
1337 case PF_PACKET:
1338 return SECCLASS_PACKET_SOCKET;
1339 case PF_KEY:
1340 return SECCLASS_KEY_SOCKET;
1341 case PF_APPLETALK:
1342 return SECCLASS_APPLETALK_SOCKET;
1343 }
1344
1345 return SECCLASS_SOCKET;
1346}
1347
1348static int selinux_genfs_get_sid(struct dentry *dentry,
1349 u16 tclass,
1350 u16 flags,
1351 u32 *sid)
1352{
1353 int rc;
1354 struct super_block *sb = dentry->d_sb;
1355 char *buffer, *path;
1356
1357 buffer = (char *)__get_free_page(GFP_KERNEL);
1358 if (!buffer)
1359 return -ENOMEM;
1360
1361 path = dentry_path_raw(dentry, buffer, PAGE_SIZE);
1362 if (IS_ERR(path))
1363 rc = PTR_ERR(path);
1364 else {
1365 if (flags & SE_SBPROC) {
1366 /* each process gets a /proc/PID/ entry. Strip off the
1367 * PID part to get a valid selinux labeling.
1368 * e.g. /proc/1/net/rpc/nfs -> /net/rpc/nfs */
1369 while (path[1] >= '0' && path[1] <= '9') {
1370 path[1] = '/';
1371 path++;
1372 }
1373 }
1374 rc = security_genfs_sid(sb->s_type->name, path, tclass, sid);
1375 }
1376 free_page((unsigned long)buffer);
1377 return rc;
1378}
1379
1380/* The inode's security attributes must be initialized before first use. */
1381static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dentry)
1382{
1383 struct superblock_security_struct *sbsec = NULL;
1384 struct inode_security_struct *isec = inode->i_security;
1385 u32 task_sid, sid = 0;
1386 u16 sclass;
1387 struct dentry *dentry;
1388#define INITCONTEXTLEN 255
1389 char *context = NULL;
1390 unsigned len = 0;
1391 int rc = 0;
1392
1393 if (isec->initialized == LABEL_INITIALIZED)
1394 return 0;
1395
1396 spin_lock(&isec->lock);
1397 if (isec->initialized == LABEL_INITIALIZED)
1398 goto out_unlock;
1399
1400 if (isec->sclass == SECCLASS_FILE)
1401 isec->sclass = inode_mode_to_security_class(inode->i_mode);
1402
1403 sbsec = inode->i_sb->s_security;
1404 if (!(sbsec->flags & SE_SBINITIALIZED)) {
1405 /* Defer initialization until selinux_complete_init,
1406 after the initial policy is loaded and the security
1407 server is ready to handle calls. */
1408 spin_lock(&sbsec->isec_lock);
1409 if (list_empty(&isec->list))
1410 list_add(&isec->list, &sbsec->isec_head);
1411 spin_unlock(&sbsec->isec_lock);
1412 goto out_unlock;
1413 }
1414
1415 sclass = isec->sclass;
1416 task_sid = isec->task_sid;
1417 sid = isec->sid;
1418 isec->initialized = LABEL_PENDING;
1419 spin_unlock(&isec->lock);
1420
1421 switch (sbsec->behavior) {
1422 case SECURITY_FS_USE_NATIVE:
1423 break;
1424 case SECURITY_FS_USE_XATTR:
1425 if (!(inode->i_opflags & IOP_XATTR)) {
1426 sid = sbsec->def_sid;
1427 break;
1428 }
1429 /* Need a dentry, since the xattr API requires one.
1430 Life would be simpler if we could just pass the inode. */
1431 if (opt_dentry) {
1432 /* Called from d_instantiate or d_splice_alias. */
1433 dentry = dget(opt_dentry);
1434 } else {
1435 /* Called from selinux_complete_init, try to find a dentry. */
1436 dentry = d_find_alias(inode);
1437 }
1438 if (!dentry) {
1439 /*
1440 * this is can be hit on boot when a file is accessed
1441 * before the policy is loaded. When we load policy we
1442 * may find inodes that have no dentry on the
1443 * sbsec->isec_head list. No reason to complain as these
1444 * will get fixed up the next time we go through
1445 * inode_doinit with a dentry, before these inodes could
1446 * be used again by userspace.
1447 */
1448 goto out;
1449 }
1450
1451 len = INITCONTEXTLEN;
1452 context = kmalloc(len+1, GFP_NOFS);
1453 if (!context) {
1454 rc = -ENOMEM;
1455 dput(dentry);
1456 goto out;
1457 }
1458 context[len] = '\0';
1459 rc = __vfs_getxattr(dentry, inode, XATTR_NAME_SELINUX, context, len);
1460 if (rc == -ERANGE) {
1461 kfree(context);
1462
1463 /* Need a larger buffer. Query for the right size. */
1464 rc = __vfs_getxattr(dentry, inode, XATTR_NAME_SELINUX, NULL, 0);
1465 if (rc < 0) {
1466 dput(dentry);
1467 goto out;
1468 }
1469 len = rc;
1470 context = kmalloc(len+1, GFP_NOFS);
1471 if (!context) {
1472 rc = -ENOMEM;
1473 dput(dentry);
1474 goto out;
1475 }
1476 context[len] = '\0';
1477 rc = __vfs_getxattr(dentry, inode, XATTR_NAME_SELINUX, context, len);
1478 }
1479 dput(dentry);
1480 if (rc < 0) {
1481 if (rc != -ENODATA) {
1482 printk(KERN_WARNING "SELinux: %s: getxattr returned "
1483 "%d for dev=%s ino=%ld\n", __func__,
1484 -rc, inode->i_sb->s_id, inode->i_ino);
1485 kfree(context);
1486 goto out;
1487 }
1488 /* Map ENODATA to the default file SID */
1489 sid = sbsec->def_sid;
1490 rc = 0;
1491 } else {
1492 rc = security_context_to_sid_default(context, rc, &sid,
1493 sbsec->def_sid,
1494 GFP_NOFS);
1495 if (rc) {
1496 char *dev = inode->i_sb->s_id;
1497 unsigned long ino = inode->i_ino;
1498
1499 if (rc == -EINVAL) {
1500 if (printk_ratelimit())
1501 printk(KERN_NOTICE "SELinux: inode=%lu on dev=%s was found to have an invalid "
1502 "context=%s. This indicates you may need to relabel the inode or the "
1503 "filesystem in question.\n", ino, dev, context);
1504 } else {
1505 printk(KERN_WARNING "SELinux: %s: context_to_sid(%s) "
1506 "returned %d for dev=%s ino=%ld\n",
1507 __func__, context, -rc, dev, ino);
1508 }
1509 kfree(context);
1510 /* Leave with the unlabeled SID */
1511 rc = 0;
1512 break;
1513 }
1514 }
1515 kfree(context);
1516 break;
1517 case SECURITY_FS_USE_TASK:
1518 sid = task_sid;
1519 break;
1520 case SECURITY_FS_USE_TRANS:
1521 /* Default to the fs SID. */
1522 sid = sbsec->sid;
1523
1524 /* Try to obtain a transition SID. */
1525 rc = security_transition_sid(task_sid, sid, sclass, NULL, &sid);
1526 if (rc)
1527 goto out;
1528 break;
1529 case SECURITY_FS_USE_MNTPOINT:
1530 sid = sbsec->mntpoint_sid;
1531 break;
1532 default:
1533 /* Default to the fs superblock SID. */
1534 sid = sbsec->sid;
1535
1536 if ((sbsec->flags & SE_SBGENFS) && !S_ISLNK(inode->i_mode)) {
1537 /* We must have a dentry to determine the label on
1538 * procfs inodes */
1539 if (opt_dentry)
1540 /* Called from d_instantiate or
1541 * d_splice_alias. */
1542 dentry = dget(opt_dentry);
1543 else
1544 /* Called from selinux_complete_init, try to
1545 * find a dentry. */
1546 dentry = d_find_alias(inode);
1547 /*
1548 * This can be hit on boot when a file is accessed
1549 * before the policy is loaded. When we load policy we
1550 * may find inodes that have no dentry on the
1551 * sbsec->isec_head list. No reason to complain as
1552 * these will get fixed up the next time we go through
1553 * inode_doinit() with a dentry, before these inodes
1554 * could be used again by userspace.
1555 */
1556 if (!dentry)
1557 goto out;
1558 rc = selinux_genfs_get_sid(dentry, sclass,
1559 sbsec->flags, &sid);
1560 dput(dentry);
1561 if (rc)
1562 goto out;
1563 }
1564 break;
1565 }
1566
1567out:
1568 spin_lock(&isec->lock);
1569 if (isec->initialized == LABEL_PENDING) {
1570 if (!sid || rc) {
1571 isec->initialized = LABEL_INVALID;
1572 goto out_unlock;
1573 }
1574
1575 isec->initialized = LABEL_INITIALIZED;
1576 isec->sid = sid;
1577 }
1578
1579out_unlock:
1580 spin_unlock(&isec->lock);
1581 return rc;
1582}
1583
1584/* Convert a Linux signal to an access vector. */
1585static inline u32 signal_to_av(int sig)
1586{
1587 u32 perm = 0;
1588
1589 switch (sig) {
1590 case SIGCHLD:
1591 /* Commonly granted from child to parent. */
1592 perm = PROCESS__SIGCHLD;
1593 break;
1594 case SIGKILL:
1595 /* Cannot be caught or ignored */
1596 perm = PROCESS__SIGKILL;
1597 break;
1598 case SIGSTOP:
1599 /* Cannot be caught or ignored */
1600 perm = PROCESS__SIGSTOP;
1601 break;
1602 default:
1603 /* All other signals. */
1604 perm = PROCESS__SIGNAL;
1605 break;
1606 }
1607
1608 return perm;
1609}
1610
1611/*
1612 * Check permission between a pair of credentials
1613 * fork check, ptrace check, etc.
1614 */
1615static int cred_has_perm(const struct cred *actor,
1616 const struct cred *target,
1617 u32 perms)
1618{
1619 u32 asid = cred_sid(actor), tsid = cred_sid(target);
1620
1621 return avc_has_perm(asid, tsid, SECCLASS_PROCESS, perms, NULL);
1622}
1623
1624/*
1625 * Check permission between a pair of tasks, e.g. signal checks,
1626 * fork check, ptrace check, etc.
1627 * tsk1 is the actor and tsk2 is the target
1628 * - this uses the default subjective creds of tsk1
1629 */
1630static int task_has_perm(const struct task_struct *tsk1,
1631 const struct task_struct *tsk2,
1632 u32 perms)
1633{
1634 const struct task_security_struct *__tsec1, *__tsec2;
1635 u32 sid1, sid2;
1636
1637 rcu_read_lock();
1638 __tsec1 = __task_cred(tsk1)->security; sid1 = __tsec1->sid;
1639 __tsec2 = __task_cred(tsk2)->security; sid2 = __tsec2->sid;
1640 rcu_read_unlock();
1641 return avc_has_perm(sid1, sid2, SECCLASS_PROCESS, perms, NULL);
1642}
1643
1644/*
1645 * Check permission between current and another task, e.g. signal checks,
1646 * fork check, ptrace check, etc.
1647 * current is the actor and tsk2 is the target
1648 * - this uses current's subjective creds
1649 */
1650static int current_has_perm(const struct task_struct *tsk,
1651 u32 perms)
1652{
1653 u32 sid, tsid;
1654
1655 sid = current_sid();
1656 tsid = task_sid(tsk);
1657 return avc_has_perm(sid, tsid, SECCLASS_PROCESS, perms, NULL);
1658}
1659
1660#if CAP_LAST_CAP > 63
1661#error Fix SELinux to handle capabilities > 63.
1662#endif
1663
1664/* Check whether a task is allowed to use a capability. */
1665static int cred_has_capability(const struct cred *cred,
1666 int cap, int audit, bool initns)
1667{
1668 struct common_audit_data ad;
1669 struct av_decision avd;
1670 u16 sclass;
1671 u32 sid = cred_sid(cred);
1672 u32 av = CAP_TO_MASK(cap);
1673 int rc;
1674
1675 ad.type = LSM_AUDIT_DATA_CAP;
1676 ad.u.cap = cap;
1677
1678 switch (CAP_TO_INDEX(cap)) {
1679 case 0:
1680 sclass = initns ? SECCLASS_CAPABILITY : SECCLASS_CAP_USERNS;
1681 break;
1682 case 1:
1683 sclass = initns ? SECCLASS_CAPABILITY2 : SECCLASS_CAP2_USERNS;
1684 break;
1685 default:
1686 printk(KERN_ERR
1687 "SELinux: out of range capability %d\n", cap);
1688 BUG();
1689 return -EINVAL;
1690 }
1691
1692 rc = avc_has_perm_noaudit(sid, sid, sclass, av, 0, &avd);
1693 if (audit == SECURITY_CAP_AUDIT) {
1694 int rc2 = avc_audit(sid, sid, sclass, av, &avd, rc, &ad, 0);
1695 if (rc2)
1696 return rc2;
1697 }
1698 return rc;
1699}
1700
1701/* Check whether a task is allowed to use a system operation. */
1702static int task_has_system(struct task_struct *tsk,
1703 u32 perms)
1704{
1705 u32 sid = task_sid(tsk);
1706
1707 return avc_has_perm(sid, SECINITSID_KERNEL,
1708 SECCLASS_SYSTEM, perms, NULL);
1709}
1710
1711/* Check whether a task has a particular permission to an inode.
1712 The 'adp' parameter is optional and allows other audit
1713 data to be passed (e.g. the dentry). */
1714static int inode_has_perm(const struct cred *cred,
1715 struct inode *inode,
1716 u32 perms,
1717 struct common_audit_data *adp)
1718{
1719 struct inode_security_struct *isec;
1720 u32 sid;
1721
1722 validate_creds(cred);
1723
1724 if (unlikely(IS_PRIVATE(inode)))
1725 return 0;
1726
1727 sid = cred_sid(cred);
1728 isec = inode->i_security;
1729
1730 return avc_has_perm(sid, isec->sid, isec->sclass, perms, adp);
1731}
1732
1733/* Same as inode_has_perm, but pass explicit audit data containing
1734 the dentry to help the auditing code to more easily generate the
1735 pathname if needed. */
1736static inline int dentry_has_perm(const struct cred *cred,
1737 struct dentry *dentry,
1738 u32 av)
1739{
1740 struct inode *inode = d_backing_inode(dentry);
1741 struct common_audit_data ad;
1742
1743 ad.type = LSM_AUDIT_DATA_DENTRY;
1744 ad.u.dentry = dentry;
1745 __inode_security_revalidate(inode, dentry, true);
1746 return inode_has_perm(cred, inode, av, &ad);
1747}
1748
1749/* Same as inode_has_perm, but pass explicit audit data containing
1750 the path to help the auditing code to more easily generate the
1751 pathname if needed. */
1752static inline int path_has_perm(const struct cred *cred,
1753 const struct path *path,
1754 u32 av)
1755{
1756 struct inode *inode = d_backing_inode(path->dentry);
1757 struct common_audit_data ad;
1758
1759 ad.type = LSM_AUDIT_DATA_PATH;
1760 ad.u.path = *path;
1761 __inode_security_revalidate(inode, path->dentry, true);
1762 return inode_has_perm(cred, inode, av, &ad);
1763}
1764
1765/* Same as path_has_perm, but uses the inode from the file struct. */
1766static inline int file_path_has_perm(const struct cred *cred,
1767 struct file *file,
1768 u32 av)
1769{
1770 struct common_audit_data ad;
1771
1772 ad.type = LSM_AUDIT_DATA_FILE;
1773 ad.u.file = file;
1774 return inode_has_perm(cred, file_inode(file), av, &ad);
1775}
1776
1777/* Check whether a task can use an open file descriptor to
1778 access an inode in a given way. Check access to the
1779 descriptor itself, and then use dentry_has_perm to
1780 check a particular permission to the file.
1781 Access to the descriptor is implicitly granted if it
1782 has the same SID as the process. If av is zero, then
1783 access to the file is not checked, e.g. for cases
1784 where only the descriptor is affected like seek. */
1785static int file_has_perm(const struct cred *cred,
1786 struct file *file,
1787 u32 av)
1788{
1789 struct file_security_struct *fsec = file->f_security;
1790 struct inode *inode = file_inode(file);
1791 struct common_audit_data ad;
1792 u32 sid = cred_sid(cred);
1793 int rc;
1794
1795 ad.type = LSM_AUDIT_DATA_FILE;
1796 ad.u.file = file;
1797
1798 if (sid != fsec->sid) {
1799 rc = avc_has_perm(sid, fsec->sid,
1800 SECCLASS_FD,
1801 FD__USE,
1802 &ad);
1803 if (rc)
1804 goto out;
1805 }
1806
1807 /* av is zero if only checking access to the descriptor. */
1808 rc = 0;
1809 if (av)
1810 rc = inode_has_perm(cred, inode, av, &ad);
1811
1812out:
1813 return rc;
1814}
1815
1816/*
1817 * Determine the label for an inode that might be unioned.
1818 */
1819static int
1820selinux_determine_inode_label(const struct task_security_struct *tsec,
1821 struct inode *dir,
1822 const struct qstr *name, u16 tclass,
1823 u32 *_new_isid)
1824{
1825 const struct superblock_security_struct *sbsec = dir->i_sb->s_security;
1826
1827 if ((sbsec->flags & SE_SBINITIALIZED) &&
1828 (sbsec->behavior == SECURITY_FS_USE_MNTPOINT)) {
1829 *_new_isid = sbsec->mntpoint_sid;
1830 } else if ((sbsec->flags & SBLABEL_MNT) &&
1831 tsec->create_sid) {
1832 *_new_isid = tsec->create_sid;
1833 } else {
1834 const struct inode_security_struct *dsec = inode_security(dir);
1835 return security_transition_sid(tsec->sid, dsec->sid, tclass,
1836 name, _new_isid);
1837 }
1838
1839 return 0;
1840}
1841
1842/* Check whether a task can create a file. */
1843static int may_create(struct inode *dir,
1844 struct dentry *dentry,
1845 u16 tclass)
1846{
1847 const struct task_security_struct *tsec = current_security();
1848 struct inode_security_struct *dsec;
1849 struct superblock_security_struct *sbsec;
1850 u32 sid, newsid;
1851 struct common_audit_data ad;
1852 int rc;
1853
1854 dsec = inode_security(dir);
1855 sbsec = dir->i_sb->s_security;
1856
1857 sid = tsec->sid;
1858
1859 ad.type = LSM_AUDIT_DATA_DENTRY;
1860 ad.u.dentry = dentry;
1861
1862 rc = avc_has_perm(sid, dsec->sid, SECCLASS_DIR,
1863 DIR__ADD_NAME | DIR__SEARCH,
1864 &ad);
1865 if (rc)
1866 return rc;
1867
1868 rc = selinux_determine_inode_label(current_security(), dir,
1869 &dentry->d_name, tclass, &newsid);
1870 if (rc)
1871 return rc;
1872
1873 rc = avc_has_perm(sid, newsid, tclass, FILE__CREATE, &ad);
1874 if (rc)
1875 return rc;
1876
1877 return avc_has_perm(newsid, sbsec->sid,
1878 SECCLASS_FILESYSTEM,
1879 FILESYSTEM__ASSOCIATE, &ad);
1880}
1881
1882/* Check whether a task can create a key. */
1883static int may_create_key(u32 ksid,
1884 struct task_struct *ctx)
1885{
1886 u32 sid = task_sid(ctx);
1887
1888 return avc_has_perm(sid, ksid, SECCLASS_KEY, KEY__CREATE, NULL);
1889}
1890
1891#define MAY_LINK 0
1892#define MAY_UNLINK 1
1893#define MAY_RMDIR 2
1894
1895/* Check whether a task can link, unlink, or rmdir a file/directory. */
1896static int may_link(struct inode *dir,
1897 struct dentry *dentry,
1898 int kind)
1899
1900{
1901 struct inode_security_struct *dsec, *isec;
1902 struct common_audit_data ad;
1903 u32 sid = current_sid();
1904 u32 av;
1905 int rc;
1906
1907 dsec = inode_security(dir);
1908 isec = backing_inode_security(dentry);
1909
1910 ad.type = LSM_AUDIT_DATA_DENTRY;
1911 ad.u.dentry = dentry;
1912
1913 av = DIR__SEARCH;
1914 av |= (kind ? DIR__REMOVE_NAME : DIR__ADD_NAME);
1915 rc = avc_has_perm(sid, dsec->sid, SECCLASS_DIR, av, &ad);
1916 if (rc)
1917 return rc;
1918
1919 switch (kind) {
1920 case MAY_LINK:
1921 av = FILE__LINK;
1922 break;
1923 case MAY_UNLINK:
1924 av = FILE__UNLINK;
1925 break;
1926 case MAY_RMDIR:
1927 av = DIR__RMDIR;
1928 break;
1929 default:
1930 printk(KERN_WARNING "SELinux: %s: unrecognized kind %d\n",
1931 __func__, kind);
1932 return 0;
1933 }
1934
1935 rc = avc_has_perm(sid, isec->sid, isec->sclass, av, &ad);
1936 return rc;
1937}
1938
1939static inline int may_rename(struct inode *old_dir,
1940 struct dentry *old_dentry,
1941 struct inode *new_dir,
1942 struct dentry *new_dentry)
1943{
1944 struct inode_security_struct *old_dsec, *new_dsec, *old_isec, *new_isec;
1945 struct common_audit_data ad;
1946 u32 sid = current_sid();
1947 u32 av;
1948 int old_is_dir, new_is_dir;
1949 int rc;
1950
1951 old_dsec = inode_security(old_dir);
1952 old_isec = backing_inode_security(old_dentry);
1953 old_is_dir = d_is_dir(old_dentry);
1954 new_dsec = inode_security(new_dir);
1955
1956 ad.type = LSM_AUDIT_DATA_DENTRY;
1957
1958 ad.u.dentry = old_dentry;
1959 rc = avc_has_perm(sid, old_dsec->sid, SECCLASS_DIR,
1960 DIR__REMOVE_NAME | DIR__SEARCH, &ad);
1961 if (rc)
1962 return rc;
1963 rc = avc_has_perm(sid, old_isec->sid,
1964 old_isec->sclass, FILE__RENAME, &ad);
1965 if (rc)
1966 return rc;
1967 if (old_is_dir && new_dir != old_dir) {
1968 rc = avc_has_perm(sid, old_isec->sid,
1969 old_isec->sclass, DIR__REPARENT, &ad);
1970 if (rc)
1971 return rc;
1972 }
1973
1974 ad.u.dentry = new_dentry;
1975 av = DIR__ADD_NAME | DIR__SEARCH;
1976 if (d_is_positive(new_dentry))
1977 av |= DIR__REMOVE_NAME;
1978 rc = avc_has_perm(sid, new_dsec->sid, SECCLASS_DIR, av, &ad);
1979 if (rc)
1980 return rc;
1981 if (d_is_positive(new_dentry)) {
1982 new_isec = backing_inode_security(new_dentry);
1983 new_is_dir = d_is_dir(new_dentry);
1984 rc = avc_has_perm(sid, new_isec->sid,
1985 new_isec->sclass,
1986 (new_is_dir ? DIR__RMDIR : FILE__UNLINK), &ad);
1987 if (rc)
1988 return rc;
1989 }
1990
1991 return 0;
1992}
1993
1994/* Check whether a task can perform a filesystem operation. */
1995static int superblock_has_perm(const struct cred *cred,
1996 struct super_block *sb,
1997 u32 perms,
1998 struct common_audit_data *ad)
1999{
2000 struct superblock_security_struct *sbsec;
2001 u32 sid = cred_sid(cred);
2002
2003 sbsec = sb->s_security;
2004 return avc_has_perm(sid, sbsec->sid, SECCLASS_FILESYSTEM, perms, ad);
2005}
2006
2007/* Convert a Linux mode and permission mask to an access vector. */
2008static inline u32 file_mask_to_av(int mode, int mask)
2009{
2010 u32 av = 0;
2011
2012 if (!S_ISDIR(mode)) {
2013 if (mask & MAY_EXEC)
2014 av |= FILE__EXECUTE;
2015 if (mask & MAY_READ)
2016 av |= FILE__READ;
2017
2018 if (mask & MAY_APPEND)
2019 av |= FILE__APPEND;
2020 else if (mask & MAY_WRITE)
2021 av |= FILE__WRITE;
2022
2023 } else {
2024 if (mask & MAY_EXEC)
2025 av |= DIR__SEARCH;
2026 if (mask & MAY_WRITE)
2027 av |= DIR__WRITE;
2028 if (mask & MAY_READ)
2029 av |= DIR__READ;
2030 }
2031
2032 return av;
2033}
2034
2035/* Convert a Linux file to an access vector. */
2036static inline u32 file_to_av(struct file *file)
2037{
2038 u32 av = 0;
2039
2040 if (file->f_mode & FMODE_READ)
2041 av |= FILE__READ;
2042 if (file->f_mode & FMODE_WRITE) {
2043 if (file->f_flags & O_APPEND)
2044 av |= FILE__APPEND;
2045 else
2046 av |= FILE__WRITE;
2047 }
2048 if (!av) {
2049 /*
2050 * Special file opened with flags 3 for ioctl-only use.
2051 */
2052 av = FILE__IOCTL;
2053 }
2054
2055 return av;
2056}
2057
2058/*
2059 * Convert a file to an access vector and include the correct open
2060 * open permission.
2061 */
2062static inline u32 open_file_to_av(struct file *file)
2063{
2064 u32 av = file_to_av(file);
2065
2066 if (selinux_policycap_openperm)
2067 av |= FILE__OPEN;
2068
2069 return av;
2070}
2071
2072/* Hook functions begin here. */
2073
2074static int selinux_binder_set_context_mgr(struct task_struct *mgr)
2075{
2076 u32 mysid = current_sid();
2077 u32 mgrsid = task_sid(mgr);
2078
2079 return avc_has_perm(mysid, mgrsid, SECCLASS_BINDER,
2080 BINDER__SET_CONTEXT_MGR, NULL);
2081}
2082
2083static int selinux_binder_transaction(struct task_struct *from,
2084 struct task_struct *to)
2085{
2086 u32 mysid = current_sid();
2087 u32 fromsid = task_sid(from);
2088 u32 tosid = task_sid(to);
2089 int rc;
2090
2091 if (mysid != fromsid) {
2092 rc = avc_has_perm(mysid, fromsid, SECCLASS_BINDER,
2093 BINDER__IMPERSONATE, NULL);
2094 if (rc)
2095 return rc;
2096 }
2097
2098 return avc_has_perm(fromsid, tosid, SECCLASS_BINDER, BINDER__CALL,
2099 NULL);
2100}
2101
2102static int selinux_binder_transfer_binder(struct task_struct *from,
2103 struct task_struct *to)
2104{
2105 u32 fromsid = task_sid(from);
2106 u32 tosid = task_sid(to);
2107
2108 return avc_has_perm(fromsid, tosid, SECCLASS_BINDER, BINDER__TRANSFER,
2109 NULL);
2110}
2111
2112static int selinux_binder_transfer_file(struct task_struct *from,
2113 struct task_struct *to,
2114 struct file *file)
2115{
2116 u32 sid = task_sid(to);
2117 struct file_security_struct *fsec = file->f_security;
2118 struct dentry *dentry = file->f_path.dentry;
2119 struct inode_security_struct *isec;
2120 struct common_audit_data ad;
2121 int rc;
2122
2123 ad.type = LSM_AUDIT_DATA_PATH;
2124 ad.u.path = file->f_path;
2125
2126 if (sid != fsec->sid) {
2127 rc = avc_has_perm(sid, fsec->sid,
2128 SECCLASS_FD,
2129 FD__USE,
2130 &ad);
2131 if (rc)
2132 return rc;
2133 }
2134
2135 if (unlikely(IS_PRIVATE(d_backing_inode(dentry))))
2136 return 0;
2137
2138 isec = backing_inode_security(dentry);
2139 return avc_has_perm(sid, isec->sid, isec->sclass, file_to_av(file),
2140 &ad);
2141}
2142
2143static int selinux_ptrace_access_check(struct task_struct *child,
2144 unsigned int mode)
2145{
2146 if (mode & PTRACE_MODE_READ) {
2147 u32 sid = current_sid();
2148 u32 csid = task_sid(child);
2149 return avc_has_perm(sid, csid, SECCLASS_FILE, FILE__READ, NULL);
2150 }
2151
2152 return current_has_perm(child, PROCESS__PTRACE);
2153}
2154
2155static int selinux_ptrace_traceme(struct task_struct *parent)
2156{
2157 return task_has_perm(parent, current, PROCESS__PTRACE);
2158}
2159
2160static int selinux_capget(struct task_struct *target, kernel_cap_t *effective,
2161 kernel_cap_t *inheritable, kernel_cap_t *permitted)
2162{
2163 return current_has_perm(target, PROCESS__GETCAP);
2164}
2165
2166static int selinux_capset(struct cred *new, const struct cred *old,
2167 const kernel_cap_t *effective,
2168 const kernel_cap_t *inheritable,
2169 const kernel_cap_t *permitted)
2170{
2171 return cred_has_perm(old, new, PROCESS__SETCAP);
2172}
2173
2174/*
2175 * (This comment used to live with the selinux_task_setuid hook,
2176 * which was removed).
2177 *
2178 * Since setuid only affects the current process, and since the SELinux
2179 * controls are not based on the Linux identity attributes, SELinux does not
2180 * need to control this operation. However, SELinux does control the use of
2181 * the CAP_SETUID and CAP_SETGID capabilities using the capable hook.
2182 */
2183
2184static int selinux_capable(const struct cred *cred, struct user_namespace *ns,
2185 int cap, int audit)
2186{
2187 return cred_has_capability(cred, cap, audit, ns == &init_user_ns);
2188}
2189
2190static int selinux_quotactl(int cmds, int type, int id, struct super_block *sb)
2191{
2192 const struct cred *cred = current_cred();
2193 int rc = 0;
2194
2195 if (!sb)
2196 return 0;
2197
2198 switch (cmds) {
2199 case Q_SYNC:
2200 case Q_QUOTAON:
2201 case Q_QUOTAOFF:
2202 case Q_SETINFO:
2203 case Q_SETQUOTA:
2204 rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAMOD, NULL);
2205 break;
2206 case Q_GETFMT:
2207 case Q_GETINFO:
2208 case Q_GETQUOTA:
2209 rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAGET, NULL);
2210 break;
2211 default:
2212 rc = 0; /* let the kernel handle invalid cmds */
2213 break;
2214 }
2215 return rc;
2216}
2217
2218static int selinux_quota_on(struct dentry *dentry)
2219{
2220 const struct cred *cred = current_cred();
2221
2222 return dentry_has_perm(cred, dentry, FILE__QUOTAON);
2223}
2224
2225static int selinux_syslog(int type)
2226{
2227 int rc;
2228
2229 switch (type) {
2230 case SYSLOG_ACTION_READ_ALL: /* Read last kernel messages */
2231 case SYSLOG_ACTION_SIZE_BUFFER: /* Return size of the log buffer */
2232 rc = task_has_system(current, SYSTEM__SYSLOG_READ);
2233 break;
2234 case SYSLOG_ACTION_CONSOLE_OFF: /* Disable logging to console */
2235 case SYSLOG_ACTION_CONSOLE_ON: /* Enable logging to console */
2236 /* Set level of messages printed to console */
2237 case SYSLOG_ACTION_CONSOLE_LEVEL:
2238 rc = task_has_system(current, SYSTEM__SYSLOG_CONSOLE);
2239 break;
2240 case SYSLOG_ACTION_CLOSE: /* Close log */
2241 case SYSLOG_ACTION_OPEN: /* Open log */
2242 case SYSLOG_ACTION_READ: /* Read from log */
2243 case SYSLOG_ACTION_READ_CLEAR: /* Read/clear last kernel messages */
2244 case SYSLOG_ACTION_CLEAR: /* Clear ring buffer */
2245 default:
2246 rc = task_has_system(current, SYSTEM__SYSLOG_MOD);
2247 break;
2248 }
2249 return rc;
2250}
2251
2252/*
2253 * Check that a process has enough memory to allocate a new virtual
2254 * mapping. 0 means there is enough memory for the allocation to
2255 * succeed and -ENOMEM implies there is not.
2256 *
2257 * Do not audit the selinux permission check, as this is applied to all
2258 * processes that allocate mappings.
2259 */
2260static int selinux_vm_enough_memory(struct mm_struct *mm, long pages)
2261{
2262 int rc, cap_sys_admin = 0;
2263
2264 rc = cred_has_capability(current_cred(), CAP_SYS_ADMIN,
2265 SECURITY_CAP_NOAUDIT, true);
2266 if (rc == 0)
2267 cap_sys_admin = 1;
2268
2269 return cap_sys_admin;
2270}
2271
2272/* binprm security operations */
2273
2274static u32 ptrace_parent_sid(struct task_struct *task)
2275{
2276 u32 sid = 0;
2277 struct task_struct *tracer;
2278
2279 rcu_read_lock();
2280 tracer = ptrace_parent(task);
2281 if (tracer)
2282 sid = task_sid(tracer);
2283 rcu_read_unlock();
2284
2285 return sid;
2286}
2287
2288static int check_nnp_nosuid(const struct linux_binprm *bprm,
2289 const struct task_security_struct *old_tsec,
2290 const struct task_security_struct *new_tsec)
2291{
2292 int nnp = (bprm->unsafe & LSM_UNSAFE_NO_NEW_PRIVS);
2293 int nosuid = !mnt_may_suid(bprm->file->f_path.mnt);
2294 int rc;
2295
2296 if (!nnp && !nosuid)
2297 return 0; /* neither NNP nor nosuid */
2298
2299 if (new_tsec->sid == old_tsec->sid)
2300 return 0; /* No change in credentials */
2301
2302 /*
2303 * The only transitions we permit under NNP or nosuid
2304 * are transitions to bounded SIDs, i.e. SIDs that are
2305 * guaranteed to only be allowed a subset of the permissions
2306 * of the current SID.
2307 */
2308 rc = security_bounded_transition(old_tsec->sid, new_tsec->sid);
2309 if (rc) {
2310 /*
2311 * On failure, preserve the errno values for NNP vs nosuid.
2312 * NNP: Operation not permitted for caller.
2313 * nosuid: Permission denied to file.
2314 */
2315 if (nnp)
2316 return -EPERM;
2317 else
2318 return -EACCES;
2319 }
2320 return 0;
2321}
2322
2323static int selinux_bprm_set_creds(struct linux_binprm *bprm)
2324{
2325 const struct task_security_struct *old_tsec;
2326 struct task_security_struct *new_tsec;
2327 struct inode_security_struct *isec;
2328 struct common_audit_data ad;
2329 struct inode *inode = file_inode(bprm->file);
2330 int rc;
2331
2332 /* SELinux context only depends on initial program or script and not
2333 * the script interpreter */
2334 if (bprm->cred_prepared)
2335 return 0;
2336
2337 old_tsec = current_security();
2338 new_tsec = bprm->cred->security;
2339 isec = inode_security(inode);
2340
2341 /* Default to the current task SID. */
2342 new_tsec->sid = old_tsec->sid;
2343 new_tsec->osid = old_tsec->sid;
2344
2345 /* Reset fs, key, and sock SIDs on execve. */
2346 new_tsec->create_sid = 0;
2347 new_tsec->keycreate_sid = 0;
2348 new_tsec->sockcreate_sid = 0;
2349
2350 if (old_tsec->exec_sid) {
2351 new_tsec->sid = old_tsec->exec_sid;
2352 /* Reset exec SID on execve. */
2353 new_tsec->exec_sid = 0;
2354
2355 /* Fail on NNP or nosuid if not an allowed transition. */
2356 rc = check_nnp_nosuid(bprm, old_tsec, new_tsec);
2357 if (rc)
2358 return rc;
2359 } else {
2360 /* Check for a default transition on this program. */
2361 rc = security_transition_sid(old_tsec->sid, isec->sid,
2362 SECCLASS_PROCESS, NULL,
2363 &new_tsec->sid);
2364 if (rc)
2365 return rc;
2366
2367 /*
2368 * Fallback to old SID on NNP or nosuid if not an allowed
2369 * transition.
2370 */
2371 rc = check_nnp_nosuid(bprm, old_tsec, new_tsec);
2372 if (rc)
2373 new_tsec->sid = old_tsec->sid;
2374 }
2375
2376 ad.type = LSM_AUDIT_DATA_FILE;
2377 ad.u.file = bprm->file;
2378
2379 if (new_tsec->sid == old_tsec->sid) {
2380 rc = avc_has_perm(old_tsec->sid, isec->sid,
2381 SECCLASS_FILE, FILE__EXECUTE_NO_TRANS, &ad);
2382 if (rc)
2383 return rc;
2384 } else {
2385 /* Check permissions for the transition. */
2386 rc = avc_has_perm(old_tsec->sid, new_tsec->sid,
2387 SECCLASS_PROCESS, PROCESS__TRANSITION, &ad);
2388 if (rc)
2389 return rc;
2390
2391 rc = avc_has_perm(new_tsec->sid, isec->sid,
2392 SECCLASS_FILE, FILE__ENTRYPOINT, &ad);
2393 if (rc)
2394 return rc;
2395
2396 /* Check for shared state */
2397 if (bprm->unsafe & LSM_UNSAFE_SHARE) {
2398 rc = avc_has_perm(old_tsec->sid, new_tsec->sid,
2399 SECCLASS_PROCESS, PROCESS__SHARE,
2400 NULL);
2401 if (rc)
2402 return -EPERM;
2403 }
2404
2405 /* Make sure that anyone attempting to ptrace over a task that
2406 * changes its SID has the appropriate permit */
2407 if (bprm->unsafe &
2408 (LSM_UNSAFE_PTRACE | LSM_UNSAFE_PTRACE_CAP)) {
2409 u32 ptsid = ptrace_parent_sid(current);
2410 if (ptsid != 0) {
2411 rc = avc_has_perm(ptsid, new_tsec->sid,
2412 SECCLASS_PROCESS,
2413 PROCESS__PTRACE, NULL);
2414 if (rc)
2415 return -EPERM;
2416 }
2417 }
2418
2419 /* Clear any possibly unsafe personality bits on exec: */
2420 bprm->per_clear |= PER_CLEAR_ON_SETID;
2421 }
2422
2423 return 0;
2424}
2425
2426static int selinux_bprm_secureexec(struct linux_binprm *bprm)
2427{
2428 const struct task_security_struct *tsec = current_security();
2429 u32 sid, osid;
2430 int atsecure = 0;
2431
2432 sid = tsec->sid;
2433 osid = tsec->osid;
2434
2435 if (osid != sid) {
2436 /* Enable secure mode for SIDs transitions unless
2437 the noatsecure permission is granted between
2438 the two SIDs, i.e. ahp returns 0. */
2439 atsecure = avc_has_perm(osid, sid,
2440 SECCLASS_PROCESS,
2441 PROCESS__NOATSECURE, NULL);
2442 }
2443
2444 return !!atsecure;
2445}
2446
2447static int match_file(const void *p, struct file *file, unsigned fd)
2448{
2449 return file_has_perm(p, file, file_to_av(file)) ? fd + 1 : 0;
2450}
2451
2452/* Derived from fs/exec.c:flush_old_files. */
2453static inline void flush_unauthorized_files(const struct cred *cred,
2454 struct files_struct *files)
2455{
2456 struct file *file, *devnull = NULL;
2457 struct tty_struct *tty;
2458 int drop_tty = 0;
2459 unsigned n;
2460
2461 tty = get_current_tty();
2462 if (tty) {
2463 spin_lock(&tty->files_lock);
2464 if (!list_empty(&tty->tty_files)) {
2465 struct tty_file_private *file_priv;
2466
2467 /* Revalidate access to controlling tty.
2468 Use file_path_has_perm on the tty path directly
2469 rather than using file_has_perm, as this particular
2470 open file may belong to another process and we are
2471 only interested in the inode-based check here. */
2472 file_priv = list_first_entry(&tty->tty_files,
2473 struct tty_file_private, list);
2474 file = file_priv->file;
2475 if (file_path_has_perm(cred, file, FILE__READ | FILE__WRITE))
2476 drop_tty = 1;
2477 }
2478 spin_unlock(&tty->files_lock);
2479 tty_kref_put(tty);
2480 }
2481 /* Reset controlling tty. */
2482 if (drop_tty)
2483 no_tty();
2484
2485 /* Revalidate access to inherited open files. */
2486 n = iterate_fd(files, 0, match_file, cred);
2487 if (!n) /* none found? */
2488 return;
2489
2490 devnull = dentry_open(&selinux_null, O_RDWR, cred);
2491 if (IS_ERR(devnull))
2492 devnull = NULL;
2493 /* replace all the matching ones with this */
2494 do {
2495 replace_fd(n - 1, devnull, 0);
2496 } while ((n = iterate_fd(files, n, match_file, cred)) != 0);
2497 if (devnull)
2498 fput(devnull);
2499}
2500
2501/*
2502 * Prepare a process for imminent new credential changes due to exec
2503 */
2504static void selinux_bprm_committing_creds(struct linux_binprm *bprm)
2505{
2506 struct task_security_struct *new_tsec;
2507 struct rlimit *rlim, *initrlim;
2508 int rc, i;
2509
2510 new_tsec = bprm->cred->security;
2511 if (new_tsec->sid == new_tsec->osid)
2512 return;
2513
2514 /* Close files for which the new task SID is not authorized. */
2515 flush_unauthorized_files(bprm->cred, current->files);
2516
2517 /* Always clear parent death signal on SID transitions. */
2518 current->pdeath_signal = 0;
2519
2520 /* Check whether the new SID can inherit resource limits from the old
2521 * SID. If not, reset all soft limits to the lower of the current
2522 * task's hard limit and the init task's soft limit.
2523 *
2524 * Note that the setting of hard limits (even to lower them) can be
2525 * controlled by the setrlimit check. The inclusion of the init task's
2526 * soft limit into the computation is to avoid resetting soft limits
2527 * higher than the default soft limit for cases where the default is
2528 * lower than the hard limit, e.g. RLIMIT_CORE or RLIMIT_STACK.
2529 */
2530 rc = avc_has_perm(new_tsec->osid, new_tsec->sid, SECCLASS_PROCESS,
2531 PROCESS__RLIMITINH, NULL);
2532 if (rc) {
2533 /* protect against do_prlimit() */
2534 task_lock(current);
2535 for (i = 0; i < RLIM_NLIMITS; i++) {
2536 rlim = current->signal->rlim + i;
2537 initrlim = init_task.signal->rlim + i;
2538 rlim->rlim_cur = min(rlim->rlim_max, initrlim->rlim_cur);
2539 }
2540 task_unlock(current);
2541 if (IS_ENABLED(CONFIG_POSIX_TIMERS))
2542 update_rlimit_cpu(current, rlimit(RLIMIT_CPU));
2543 }
2544}
2545
2546/*
2547 * Clean up the process immediately after the installation of new credentials
2548 * due to exec
2549 */
2550static void selinux_bprm_committed_creds(struct linux_binprm *bprm)
2551{
2552 const struct task_security_struct *tsec = current_security();
2553 struct itimerval itimer;
2554 u32 osid, sid;
2555 int rc, i;
2556
2557 osid = tsec->osid;
2558 sid = tsec->sid;
2559
2560 if (sid == osid)
2561 return;
2562
2563 /* Check whether the new SID can inherit signal state from the old SID.
2564 * If not, clear itimers to avoid subsequent signal generation and
2565 * flush and unblock signals.
2566 *
2567 * This must occur _after_ the task SID has been updated so that any
2568 * kill done after the flush will be checked against the new SID.
2569 */
2570 rc = avc_has_perm(osid, sid, SECCLASS_PROCESS, PROCESS__SIGINH, NULL);
2571 if (rc) {
2572 if (IS_ENABLED(CONFIG_POSIX_TIMERS)) {
2573 memset(&itimer, 0, sizeof itimer);
2574 for (i = 0; i < 3; i++)
2575 do_setitimer(i, &itimer, NULL);
2576 }
2577 spin_lock_irq(¤t->sighand->siglock);
2578 if (!fatal_signal_pending(current)) {
2579 flush_sigqueue(¤t->pending);
2580 flush_sigqueue(¤t->signal->shared_pending);
2581 flush_signal_handlers(current, 1);
2582 sigemptyset(¤t->blocked);
2583 recalc_sigpending();
2584 }
2585 spin_unlock_irq(¤t->sighand->siglock);
2586 }
2587
2588 /* Wake up the parent if it is waiting so that it can recheck
2589 * wait permission to the new task SID. */
2590 read_lock(&tasklist_lock);
2591 __wake_up_parent(current, current->real_parent);
2592 read_unlock(&tasklist_lock);
2593}
2594
2595/* superblock security operations */
2596
2597static int selinux_sb_alloc_security(struct super_block *sb)
2598{
2599 return superblock_alloc_security(sb);
2600}
2601
2602static void selinux_sb_free_security(struct super_block *sb)
2603{
2604 superblock_free_security(sb);
2605}
2606
2607static inline int match_prefix(char *prefix, int plen, char *option, int olen)
2608{
2609 if (plen > olen)
2610 return 0;
2611
2612 return !memcmp(prefix, option, plen);
2613}
2614
2615static inline int selinux_option(char *option, int len)
2616{
2617 return (match_prefix(CONTEXT_STR, sizeof(CONTEXT_STR)-1, option, len) ||
2618 match_prefix(FSCONTEXT_STR, sizeof(FSCONTEXT_STR)-1, option, len) ||
2619 match_prefix(DEFCONTEXT_STR, sizeof(DEFCONTEXT_STR)-1, option, len) ||
2620 match_prefix(ROOTCONTEXT_STR, sizeof(ROOTCONTEXT_STR)-1, option, len) ||
2621 match_prefix(LABELSUPP_STR, sizeof(LABELSUPP_STR)-1, option, len));
2622}
2623
2624static inline void take_option(char **to, char *from, int *first, int len)
2625{
2626 if (!*first) {
2627 **to = ',';
2628 *to += 1;
2629 } else
2630 *first = 0;
2631 memcpy(*to, from, len);
2632 *to += len;
2633}
2634
2635static inline void take_selinux_option(char **to, char *from, int *first,
2636 int len)
2637{
2638 int current_size = 0;
2639
2640 if (!*first) {
2641 **to = '|';
2642 *to += 1;
2643 } else
2644 *first = 0;
2645
2646 while (current_size < len) {
2647 if (*from != '"') {
2648 **to = *from;
2649 *to += 1;
2650 }
2651 from += 1;
2652 current_size += 1;
2653 }
2654}
2655
2656static int selinux_sb_copy_data(char *orig, char *copy)
2657{
2658 int fnosec, fsec, rc = 0;
2659 char *in_save, *in_curr, *in_end;
2660 char *sec_curr, *nosec_save, *nosec;
2661 int open_quote = 0;
2662
2663 in_curr = orig;
2664 sec_curr = copy;
2665
2666 nosec = (char *)get_zeroed_page(GFP_KERNEL);
2667 if (!nosec) {
2668 rc = -ENOMEM;
2669 goto out;
2670 }
2671
2672 nosec_save = nosec;
2673 fnosec = fsec = 1;
2674 in_save = in_end = orig;
2675
2676 do {
2677 if (*in_end == '"')
2678 open_quote = !open_quote;
2679 if ((*in_end == ',' && open_quote == 0) ||
2680 *in_end == '\0') {
2681 int len = in_end - in_curr;
2682
2683 if (selinux_option(in_curr, len))
2684 take_selinux_option(&sec_curr, in_curr, &fsec, len);
2685 else
2686 take_option(&nosec, in_curr, &fnosec, len);
2687
2688 in_curr = in_end + 1;
2689 }
2690 } while (*in_end++);
2691
2692 strcpy(in_save, nosec_save);
2693 free_page((unsigned long)nosec_save);
2694out:
2695 return rc;
2696}
2697
2698static int selinux_sb_remount(struct super_block *sb, void *data)
2699{
2700 int rc, i, *flags;
2701 struct security_mnt_opts opts;
2702 char *secdata, **mount_options;
2703 struct superblock_security_struct *sbsec = sb->s_security;
2704
2705 if (!(sbsec->flags & SE_SBINITIALIZED))
2706 return 0;
2707
2708 if (!data)
2709 return 0;
2710
2711 if (sb->s_type->fs_flags & FS_BINARY_MOUNTDATA)
2712 return 0;
2713
2714 security_init_mnt_opts(&opts);
2715 secdata = alloc_secdata();
2716 if (!secdata)
2717 return -ENOMEM;
2718 rc = selinux_sb_copy_data(data, secdata);
2719 if (rc)
2720 goto out_free_secdata;
2721
2722 rc = selinux_parse_opts_str(secdata, &opts);
2723 if (rc)
2724 goto out_free_secdata;
2725
2726 mount_options = opts.mnt_opts;
2727 flags = opts.mnt_opts_flags;
2728
2729 for (i = 0; i < opts.num_mnt_opts; i++) {
2730 u32 sid;
2731
2732 if (flags[i] == SBLABEL_MNT)
2733 continue;
2734 rc = security_context_str_to_sid(mount_options[i], &sid, GFP_KERNEL);
2735 if (rc) {
2736 printk(KERN_WARNING "SELinux: security_context_str_to_sid"
2737 "(%s) failed for (dev %s, type %s) errno=%d\n",
2738 mount_options[i], sb->s_id, sb->s_type->name, rc);
2739 goto out_free_opts;
2740 }
2741 rc = -EINVAL;
2742 switch (flags[i]) {
2743 case FSCONTEXT_MNT:
2744 if (bad_option(sbsec, FSCONTEXT_MNT, sbsec->sid, sid))
2745 goto out_bad_option;
2746 break;
2747 case CONTEXT_MNT:
2748 if (bad_option(sbsec, CONTEXT_MNT, sbsec->mntpoint_sid, sid))
2749 goto out_bad_option;
2750 break;
2751 case ROOTCONTEXT_MNT: {
2752 struct inode_security_struct *root_isec;
2753 root_isec = backing_inode_security(sb->s_root);
2754
2755 if (bad_option(sbsec, ROOTCONTEXT_MNT, root_isec->sid, sid))
2756 goto out_bad_option;
2757 break;
2758 }
2759 case DEFCONTEXT_MNT:
2760 if (bad_option(sbsec, DEFCONTEXT_MNT, sbsec->def_sid, sid))
2761 goto out_bad_option;
2762 break;
2763 default:
2764 goto out_free_opts;
2765 }
2766 }
2767
2768 rc = 0;
2769out_free_opts:
2770 security_free_mnt_opts(&opts);
2771out_free_secdata:
2772 free_secdata(secdata);
2773 return rc;
2774out_bad_option:
2775 printk(KERN_WARNING "SELinux: unable to change security options "
2776 "during remount (dev %s, type=%s)\n", sb->s_id,
2777 sb->s_type->name);
2778 goto out_free_opts;
2779}
2780
2781static int selinux_sb_kern_mount(struct super_block *sb, int flags, void *data)
2782{
2783 const struct cred *cred = current_cred();
2784 struct common_audit_data ad;
2785 int rc;
2786
2787 rc = superblock_doinit(sb, data);
2788 if (rc)
2789 return rc;
2790
2791 /* Allow all mounts performed by the kernel */
2792 if (flags & MS_KERNMOUNT)
2793 return 0;
2794
2795 ad.type = LSM_AUDIT_DATA_DENTRY;
2796 ad.u.dentry = sb->s_root;
2797 return superblock_has_perm(cred, sb, FILESYSTEM__MOUNT, &ad);
2798}
2799
2800static int selinux_sb_statfs(struct dentry *dentry)
2801{
2802 const struct cred *cred = current_cred();
2803 struct common_audit_data ad;
2804
2805 ad.type = LSM_AUDIT_DATA_DENTRY;
2806 ad.u.dentry = dentry->d_sb->s_root;
2807 return superblock_has_perm(cred, dentry->d_sb, FILESYSTEM__GETATTR, &ad);
2808}
2809
2810static int selinux_mount(const char *dev_name,
2811 const struct path *path,
2812 const char *type,
2813 unsigned long flags,
2814 void *data)
2815{
2816 const struct cred *cred = current_cred();
2817
2818 if (flags & MS_REMOUNT)
2819 return superblock_has_perm(cred, path->dentry->d_sb,
2820 FILESYSTEM__REMOUNT, NULL);
2821 else
2822 return path_has_perm(cred, path, FILE__MOUNTON);
2823}
2824
2825static int selinux_umount(struct vfsmount *mnt, int flags)
2826{
2827 const struct cred *cred = current_cred();
2828
2829 return superblock_has_perm(cred, mnt->mnt_sb,
2830 FILESYSTEM__UNMOUNT, NULL);
2831}
2832
2833/* inode security operations */
2834
2835static int selinux_inode_alloc_security(struct inode *inode)
2836{
2837 return inode_alloc_security(inode);
2838}
2839
2840static void selinux_inode_free_security(struct inode *inode)
2841{
2842 inode_free_security(inode);
2843}
2844
2845static int selinux_dentry_init_security(struct dentry *dentry, int mode,
2846 const struct qstr *name, void **ctx,
2847 u32 *ctxlen)
2848{
2849 u32 newsid;
2850 int rc;
2851
2852 rc = selinux_determine_inode_label(current_security(),
2853 d_inode(dentry->d_parent), name,
2854 inode_mode_to_security_class(mode),
2855 &newsid);
2856 if (rc)
2857 return rc;
2858
2859 return security_sid_to_context(newsid, (char **)ctx, ctxlen);
2860}
2861
2862static int selinux_dentry_create_files_as(struct dentry *dentry, int mode,
2863 struct qstr *name,
2864 const struct cred *old,
2865 struct cred *new)
2866{
2867 u32 newsid;
2868 int rc;
2869 struct task_security_struct *tsec;
2870
2871 rc = selinux_determine_inode_label(old->security,
2872 d_inode(dentry->d_parent), name,
2873 inode_mode_to_security_class(mode),
2874 &newsid);
2875 if (rc)
2876 return rc;
2877
2878 tsec = new->security;
2879 tsec->create_sid = newsid;
2880 return 0;
2881}
2882
2883static int selinux_inode_init_security(struct inode *inode, struct inode *dir,
2884 const struct qstr *qstr,
2885 const char **name,
2886 void **value, size_t *len)
2887{
2888 const struct task_security_struct *tsec = current_security();
2889 struct superblock_security_struct *sbsec;
2890 u32 sid, newsid, clen;
2891 int rc;
2892 char *context;
2893
2894 sbsec = dir->i_sb->s_security;
2895
2896 sid = tsec->sid;
2897 newsid = tsec->create_sid;
2898
2899 rc = selinux_determine_inode_label(current_security(),
2900 dir, qstr,
2901 inode_mode_to_security_class(inode->i_mode),
2902 &newsid);
2903 if (rc)
2904 return rc;
2905
2906 /* Possibly defer initialization to selinux_complete_init. */
2907 if (sbsec->flags & SE_SBINITIALIZED) {
2908 struct inode_security_struct *isec = inode->i_security;
2909 isec->sclass = inode_mode_to_security_class(inode->i_mode);
2910 isec->sid = newsid;
2911 isec->initialized = LABEL_INITIALIZED;
2912 }
2913
2914 if (!ss_initialized || !(sbsec->flags & SBLABEL_MNT))
2915 return -EOPNOTSUPP;
2916
2917 if (name)
2918 *name = XATTR_SELINUX_SUFFIX;
2919
2920 if (value && len) {
2921 rc = security_sid_to_context_force(newsid, &context, &clen);
2922 if (rc)
2923 return rc;
2924 *value = context;
2925 *len = clen;
2926 }
2927
2928 return 0;
2929}
2930
2931static int selinux_inode_create(struct inode *dir, struct dentry *dentry, umode_t mode)
2932{
2933 return may_create(dir, dentry, SECCLASS_FILE);
2934}
2935
2936static int selinux_inode_link(struct dentry *old_dentry, struct inode *dir, struct dentry *new_dentry)
2937{
2938 return may_link(dir, old_dentry, MAY_LINK);
2939}
2940
2941static int selinux_inode_unlink(struct inode *dir, struct dentry *dentry)
2942{
2943 return may_link(dir, dentry, MAY_UNLINK);
2944}
2945
2946static int selinux_inode_symlink(struct inode *dir, struct dentry *dentry, const char *name)
2947{
2948 return may_create(dir, dentry, SECCLASS_LNK_FILE);
2949}
2950
2951static int selinux_inode_mkdir(struct inode *dir, struct dentry *dentry, umode_t mask)
2952{
2953 return may_create(dir, dentry, SECCLASS_DIR);
2954}
2955
2956static int selinux_inode_rmdir(struct inode *dir, struct dentry *dentry)
2957{
2958 return may_link(dir, dentry, MAY_RMDIR);
2959}
2960
2961static int selinux_inode_mknod(struct inode *dir, struct dentry *dentry, umode_t mode, dev_t dev)
2962{
2963 return may_create(dir, dentry, inode_mode_to_security_class(mode));
2964}
2965
2966static int selinux_inode_rename(struct inode *old_inode, struct dentry *old_dentry,
2967 struct inode *new_inode, struct dentry *new_dentry)
2968{
2969 return may_rename(old_inode, old_dentry, new_inode, new_dentry);
2970}
2971
2972static int selinux_inode_readlink(struct dentry *dentry)
2973{
2974 const struct cred *cred = current_cred();
2975
2976 return dentry_has_perm(cred, dentry, FILE__READ);
2977}
2978
2979static int selinux_inode_follow_link(struct dentry *dentry, struct inode *inode,
2980 bool rcu)
2981{
2982 const struct cred *cred = current_cred();
2983 struct common_audit_data ad;
2984 struct inode_security_struct *isec;
2985 u32 sid;
2986
2987 validate_creds(cred);
2988
2989 ad.type = LSM_AUDIT_DATA_DENTRY;
2990 ad.u.dentry = dentry;
2991 sid = cred_sid(cred);
2992 isec = inode_security_rcu(inode, rcu);
2993 if (IS_ERR(isec))
2994 return PTR_ERR(isec);
2995
2996 return avc_has_perm_flags(sid, isec->sid, isec->sclass, FILE__READ, &ad,
2997 rcu ? MAY_NOT_BLOCK : 0);
2998}
2999
3000static noinline int audit_inode_permission(struct inode *inode,
3001 u32 perms, u32 audited, u32 denied,
3002 int result,
3003 unsigned flags)
3004{
3005 struct common_audit_data ad;
3006 struct inode_security_struct *isec = inode->i_security;
3007 int rc;
3008
3009 ad.type = LSM_AUDIT_DATA_INODE;
3010 ad.u.inode = inode;
3011
3012 rc = slow_avc_audit(current_sid(), isec->sid, isec->sclass, perms,
3013 audited, denied, result, &ad, flags);
3014 if (rc)
3015 return rc;
3016 return 0;
3017}
3018
3019static int selinux_inode_permission(struct inode *inode, int mask)
3020{
3021 const struct cred *cred = current_cred();
3022 u32 perms;
3023 bool from_access;
3024 unsigned flags = mask & MAY_NOT_BLOCK;
3025 struct inode_security_struct *isec;
3026 u32 sid;
3027 struct av_decision avd;
3028 int rc, rc2;
3029 u32 audited, denied;
3030
3031 from_access = mask & MAY_ACCESS;
3032 mask &= (MAY_READ|MAY_WRITE|MAY_EXEC|MAY_APPEND);
3033
3034 /* No permission to check. Existence test. */
3035 if (!mask)
3036 return 0;
3037
3038 validate_creds(cred);
3039
3040 if (unlikely(IS_PRIVATE(inode)))
3041 return 0;
3042
3043 perms = file_mask_to_av(inode->i_mode, mask);
3044
3045 sid = cred_sid(cred);
3046 isec = inode_security_rcu(inode, flags & MAY_NOT_BLOCK);
3047 if (IS_ERR(isec))
3048 return PTR_ERR(isec);
3049
3050 rc = avc_has_perm_noaudit(sid, isec->sid, isec->sclass, perms, 0, &avd);
3051 audited = avc_audit_required(perms, &avd, rc,
3052 from_access ? FILE__AUDIT_ACCESS : 0,
3053 &denied);
3054 if (likely(!audited))
3055 return rc;
3056
3057 rc2 = audit_inode_permission(inode, perms, audited, denied, rc, flags);
3058 if (rc2)
3059 return rc2;
3060 return rc;
3061}
3062
3063static int selinux_inode_setattr(struct dentry *dentry, struct iattr *iattr)
3064{
3065 const struct cred *cred = current_cred();
3066 unsigned int ia_valid = iattr->ia_valid;
3067 __u32 av = FILE__WRITE;
3068
3069 /* ATTR_FORCE is just used for ATTR_KILL_S[UG]ID. */
3070 if (ia_valid & ATTR_FORCE) {
3071 ia_valid &= ~(ATTR_KILL_SUID | ATTR_KILL_SGID | ATTR_MODE |
3072 ATTR_FORCE);
3073 if (!ia_valid)
3074 return 0;
3075 }
3076
3077 if (ia_valid & (ATTR_MODE | ATTR_UID | ATTR_GID |
3078 ATTR_ATIME_SET | ATTR_MTIME_SET | ATTR_TIMES_SET))
3079 return dentry_has_perm(cred, dentry, FILE__SETATTR);
3080
3081 if (selinux_policycap_openperm && (ia_valid & ATTR_SIZE)
3082 && !(ia_valid & ATTR_FILE))
3083 av |= FILE__OPEN;
3084
3085 return dentry_has_perm(cred, dentry, av);
3086}
3087
3088static int selinux_inode_getattr(const struct path *path)
3089{
3090 return path_has_perm(current_cred(), path, FILE__GETATTR);
3091}
3092
3093static int selinux_inode_setotherxattr(struct dentry *dentry, const char *name)
3094{
3095 const struct cred *cred = current_cred();
3096
3097 if (!strncmp(name, XATTR_SECURITY_PREFIX,
3098 sizeof XATTR_SECURITY_PREFIX - 1)) {
3099 if (!strcmp(name, XATTR_NAME_CAPS)) {
3100 if (!capable(CAP_SETFCAP))
3101 return -EPERM;
3102 } else if (!capable(CAP_SYS_ADMIN)) {
3103 /* A different attribute in the security namespace.
3104 Restrict to administrator. */
3105 return -EPERM;
3106 }
3107 }
3108
3109 /* Not an attribute we recognize, so just check the
3110 ordinary setattr permission. */
3111 return dentry_has_perm(cred, dentry, FILE__SETATTR);
3112}
3113
3114static int selinux_inode_setxattr(struct dentry *dentry, const char *name,
3115 const void *value, size_t size, int flags)
3116{
3117 struct inode *inode = d_backing_inode(dentry);
3118 struct inode_security_struct *isec;
3119 struct superblock_security_struct *sbsec;
3120 struct common_audit_data ad;
3121 u32 newsid, sid = current_sid();
3122 int rc = 0;
3123
3124 if (strcmp(name, XATTR_NAME_SELINUX))
3125 return selinux_inode_setotherxattr(dentry, name);
3126
3127 sbsec = inode->i_sb->s_security;
3128 if (!(sbsec->flags & SBLABEL_MNT))
3129 return -EOPNOTSUPP;
3130
3131 if (!inode_owner_or_capable(inode))
3132 return -EPERM;
3133
3134 ad.type = LSM_AUDIT_DATA_DENTRY;
3135 ad.u.dentry = dentry;
3136
3137 isec = backing_inode_security(dentry);
3138 rc = avc_has_perm(sid, isec->sid, isec->sclass,
3139 FILE__RELABELFROM, &ad);
3140 if (rc)
3141 return rc;
3142
3143 rc = security_context_to_sid(value, size, &newsid, GFP_KERNEL);
3144 if (rc == -EINVAL) {
3145 if (!capable(CAP_MAC_ADMIN)) {
3146 struct audit_buffer *ab;
3147 size_t audit_size;
3148 const char *str;
3149
3150 /* We strip a nul only if it is at the end, otherwise the
3151 * context contains a nul and we should audit that */
3152 if (value) {
3153 str = value;
3154 if (str[size - 1] == '\0')
3155 audit_size = size - 1;
3156 else
3157 audit_size = size;
3158 } else {
3159 str = "";
3160 audit_size = 0;
3161 }
3162 ab = audit_log_start(current->audit_context, GFP_ATOMIC, AUDIT_SELINUX_ERR);
3163 audit_log_format(ab, "op=setxattr invalid_context=");
3164 audit_log_n_untrustedstring(ab, value, audit_size);
3165 audit_log_end(ab);
3166
3167 return rc;
3168 }
3169 rc = security_context_to_sid_force(value, size, &newsid);
3170 }
3171 if (rc)
3172 return rc;
3173
3174 rc = avc_has_perm(sid, newsid, isec->sclass,
3175 FILE__RELABELTO, &ad);
3176 if (rc)
3177 return rc;
3178
3179 rc = security_validate_transition(isec->sid, newsid, sid,
3180 isec->sclass);
3181 if (rc)
3182 return rc;
3183
3184 return avc_has_perm(newsid,
3185 sbsec->sid,
3186 SECCLASS_FILESYSTEM,
3187 FILESYSTEM__ASSOCIATE,
3188 &ad);
3189}
3190
3191static void selinux_inode_post_setxattr(struct dentry *dentry, const char *name,
3192 const void *value, size_t size,
3193 int flags)
3194{
3195 struct inode *inode = d_backing_inode(dentry);
3196 struct inode_security_struct *isec;
3197 u32 newsid;
3198 int rc;
3199
3200 if (strcmp(name, XATTR_NAME_SELINUX)) {
3201 /* Not an attribute we recognize, so nothing to do. */
3202 return;
3203 }
3204
3205 rc = security_context_to_sid_force(value, size, &newsid);
3206 if (rc) {
3207 printk(KERN_ERR "SELinux: unable to map context to SID"
3208 "for (%s, %lu), rc=%d\n",
3209 inode->i_sb->s_id, inode->i_ino, -rc);
3210 return;
3211 }
3212
3213 isec = backing_inode_security(dentry);
3214 spin_lock(&isec->lock);
3215 isec->sclass = inode_mode_to_security_class(inode->i_mode);
3216 isec->sid = newsid;
3217 isec->initialized = LABEL_INITIALIZED;
3218 spin_unlock(&isec->lock);
3219
3220 return;
3221}
3222
3223static int selinux_inode_getxattr(struct dentry *dentry, const char *name)
3224{
3225 const struct cred *cred = current_cred();
3226
3227 return dentry_has_perm(cred, dentry, FILE__GETATTR);
3228}
3229
3230static int selinux_inode_listxattr(struct dentry *dentry)
3231{
3232 const struct cred *cred = current_cred();
3233
3234 return dentry_has_perm(cred, dentry, FILE__GETATTR);
3235}
3236
3237static int selinux_inode_removexattr(struct dentry *dentry, const char *name)
3238{
3239 if (strcmp(name, XATTR_NAME_SELINUX))
3240 return selinux_inode_setotherxattr(dentry, name);
3241
3242 /* No one is allowed to remove a SELinux security label.
3243 You can change the label, but all data must be labeled. */
3244 return -EACCES;
3245}
3246
3247/*
3248 * Copy the inode security context value to the user.
3249 *
3250 * Permission check is handled by selinux_inode_getxattr hook.
3251 */
3252static int selinux_inode_getsecurity(struct inode *inode, const char *name, void **buffer, bool alloc)
3253{
3254 u32 size;
3255 int error;
3256 char *context = NULL;
3257 struct inode_security_struct *isec;
3258
3259 if (strcmp(name, XATTR_SELINUX_SUFFIX))
3260 return -EOPNOTSUPP;
3261
3262 /*
3263 * If the caller has CAP_MAC_ADMIN, then get the raw context
3264 * value even if it is not defined by current policy; otherwise,
3265 * use the in-core value under current policy.
3266 * Use the non-auditing forms of the permission checks since
3267 * getxattr may be called by unprivileged processes commonly
3268 * and lack of permission just means that we fall back to the
3269 * in-core context value, not a denial.
3270 */
3271 error = cap_capable(current_cred(), &init_user_ns, CAP_MAC_ADMIN,
3272 SECURITY_CAP_NOAUDIT);
3273 if (!error)
3274 error = cred_has_capability(current_cred(), CAP_MAC_ADMIN,
3275 SECURITY_CAP_NOAUDIT, true);
3276 isec = inode_security(inode);
3277 if (!error)
3278 error = security_sid_to_context_force(isec->sid, &context,
3279 &size);
3280 else
3281 error = security_sid_to_context(isec->sid, &context, &size);
3282 if (error)
3283 return error;
3284 error = size;
3285 if (alloc) {
3286 *buffer = context;
3287 goto out_nofree;
3288 }
3289 kfree(context);
3290out_nofree:
3291 return error;
3292}
3293
3294static int selinux_inode_setsecurity(struct inode *inode, const char *name,
3295 const void *value, size_t size, int flags)
3296{
3297 struct inode_security_struct *isec = inode_security_novalidate(inode);
3298 u32 newsid;
3299 int rc;
3300
3301 if (strcmp(name, XATTR_SELINUX_SUFFIX))
3302 return -EOPNOTSUPP;
3303
3304 if (!value || !size)
3305 return -EACCES;
3306
3307 rc = security_context_to_sid(value, size, &newsid, GFP_KERNEL);
3308 if (rc)
3309 return rc;
3310
3311 spin_lock(&isec->lock);
3312 isec->sclass = inode_mode_to_security_class(inode->i_mode);
3313 isec->sid = newsid;
3314 isec->initialized = LABEL_INITIALIZED;
3315 spin_unlock(&isec->lock);
3316 return 0;
3317}
3318
3319static int selinux_inode_listsecurity(struct inode *inode, char *buffer, size_t buffer_size)
3320{
3321 const int len = sizeof(XATTR_NAME_SELINUX);
3322 if (buffer && len <= buffer_size)
3323 memcpy(buffer, XATTR_NAME_SELINUX, len);
3324 return len;
3325}
3326
3327static void selinux_inode_getsecid(struct inode *inode, u32 *secid)
3328{
3329 struct inode_security_struct *isec = inode_security_novalidate(inode);
3330 *secid = isec->sid;
3331}
3332
3333static int selinux_inode_copy_up(struct dentry *src, struct cred **new)
3334{
3335 u32 sid;
3336 struct task_security_struct *tsec;
3337 struct cred *new_creds = *new;
3338
3339 if (new_creds == NULL) {
3340 new_creds = prepare_creds();
3341 if (!new_creds)
3342 return -ENOMEM;
3343 }
3344
3345 tsec = new_creds->security;
3346 /* Get label from overlay inode and set it in create_sid */
3347 selinux_inode_getsecid(d_inode(src), &sid);
3348 tsec->create_sid = sid;
3349 *new = new_creds;
3350 return 0;
3351}
3352
3353static int selinux_inode_copy_up_xattr(const char *name)
3354{
3355 /* The copy_up hook above sets the initial context on an inode, but we
3356 * don't then want to overwrite it by blindly copying all the lower
3357 * xattrs up. Instead, we have to filter out SELinux-related xattrs.
3358 */
3359 if (strcmp(name, XATTR_NAME_SELINUX) == 0)
3360 return 1; /* Discard */
3361 /*
3362 * Any other attribute apart from SELINUX is not claimed, supported
3363 * by selinux.
3364 */
3365 return -EOPNOTSUPP;
3366}
3367
3368/* file security operations */
3369
3370static int selinux_revalidate_file_permission(struct file *file, int mask)
3371{
3372 const struct cred *cred = current_cred();
3373 struct inode *inode = file_inode(file);
3374
3375 /* file_mask_to_av won't add FILE__WRITE if MAY_APPEND is set */
3376 if ((file->f_flags & O_APPEND) && (mask & MAY_WRITE))
3377 mask |= MAY_APPEND;
3378
3379 return file_has_perm(cred, file,
3380 file_mask_to_av(inode->i_mode, mask));
3381}
3382
3383static int selinux_file_permission(struct file *file, int mask)
3384{
3385 struct inode *inode = file_inode(file);
3386 struct file_security_struct *fsec = file->f_security;
3387 struct inode_security_struct *isec;
3388 u32 sid = current_sid();
3389
3390 if (!mask)
3391 /* No permission to check. Existence test. */
3392 return 0;
3393
3394 isec = inode_security(inode);
3395 if (sid == fsec->sid && fsec->isid == isec->sid &&
3396 fsec->pseqno == avc_policy_seqno())
3397 /* No change since file_open check. */
3398 return 0;
3399
3400 return selinux_revalidate_file_permission(file, mask);
3401}
3402
3403static int selinux_file_alloc_security(struct file *file)
3404{
3405 return file_alloc_security(file);
3406}
3407
3408static void selinux_file_free_security(struct file *file)
3409{
3410 file_free_security(file);
3411}
3412
3413/*
3414 * Check whether a task has the ioctl permission and cmd
3415 * operation to an inode.
3416 */
3417static int ioctl_has_perm(const struct cred *cred, struct file *file,
3418 u32 requested, u16 cmd)
3419{
3420 struct common_audit_data ad;
3421 struct file_security_struct *fsec = file->f_security;
3422 struct inode *inode = file_inode(file);
3423 struct inode_security_struct *isec;
3424 struct lsm_ioctlop_audit ioctl;
3425 u32 ssid = cred_sid(cred);
3426 int rc;
3427 u8 driver = cmd >> 8;
3428 u8 xperm = cmd & 0xff;
3429
3430 ad.type = LSM_AUDIT_DATA_IOCTL_OP;
3431 ad.u.op = &ioctl;
3432 ad.u.op->cmd = cmd;
3433 ad.u.op->path = file->f_path;
3434
3435 if (ssid != fsec->sid) {
3436 rc = avc_has_perm(ssid, fsec->sid,
3437 SECCLASS_FD,
3438 FD__USE,
3439 &ad);
3440 if (rc)
3441 goto out;
3442 }
3443
3444 if (unlikely(IS_PRIVATE(inode)))
3445 return 0;
3446
3447 isec = inode_security(inode);
3448 rc = avc_has_extended_perms(ssid, isec->sid, isec->sclass,
3449 requested, driver, xperm, &ad);
3450out:
3451 return rc;
3452}
3453
3454static int selinux_file_ioctl(struct file *file, unsigned int cmd,
3455 unsigned long arg)
3456{
3457 const struct cred *cred = current_cred();
3458 int error = 0;
3459
3460 switch (cmd) {
3461 case FIONREAD:
3462 /* fall through */
3463 case FIBMAP:
3464 /* fall through */
3465 case FIGETBSZ:
3466 /* fall through */
3467 case FS_IOC_GETFLAGS:
3468 /* fall through */
3469 case FS_IOC_GETVERSION:
3470 error = file_has_perm(cred, file, FILE__GETATTR);
3471 break;
3472
3473 case FS_IOC_SETFLAGS:
3474 /* fall through */
3475 case FS_IOC_SETVERSION:
3476 error = file_has_perm(cred, file, FILE__SETATTR);
3477 break;
3478
3479 /* sys_ioctl() checks */
3480 case FIONBIO:
3481 /* fall through */
3482 case FIOASYNC:
3483 error = file_has_perm(cred, file, 0);
3484 break;
3485
3486 case KDSKBENT:
3487 case KDSKBSENT:
3488 error = cred_has_capability(cred, CAP_SYS_TTY_CONFIG,
3489 SECURITY_CAP_AUDIT, true);
3490 break;
3491
3492 /* default case assumes that the command will go
3493 * to the file's ioctl() function.
3494 */
3495 default:
3496 error = ioctl_has_perm(cred, file, FILE__IOCTL, (u16) cmd);
3497 }
3498 return error;
3499}
3500
3501static int default_noexec;
3502
3503static int file_map_prot_check(struct file *file, unsigned long prot, int shared)
3504{
3505 const struct cred *cred = current_cred();
3506 int rc = 0;
3507
3508 if (default_noexec &&
3509 (prot & PROT_EXEC) && (!file || IS_PRIVATE(file_inode(file)) ||
3510 (!shared && (prot & PROT_WRITE)))) {
3511 /*
3512 * We are making executable an anonymous mapping or a
3513 * private file mapping that will also be writable.
3514 * This has an additional check.
3515 */
3516 rc = cred_has_perm(cred, cred, PROCESS__EXECMEM);
3517 if (rc)
3518 goto error;
3519 }
3520
3521 if (file) {
3522 /* read access is always possible with a mapping */
3523 u32 av = FILE__READ;
3524
3525 /* write access only matters if the mapping is shared */
3526 if (shared && (prot & PROT_WRITE))
3527 av |= FILE__WRITE;
3528
3529 if (prot & PROT_EXEC)
3530 av |= FILE__EXECUTE;
3531
3532 return file_has_perm(cred, file, av);
3533 }
3534
3535error:
3536 return rc;
3537}
3538
3539static int selinux_mmap_addr(unsigned long addr)
3540{
3541 int rc = 0;
3542
3543 if (addr < CONFIG_LSM_MMAP_MIN_ADDR) {
3544 u32 sid = current_sid();
3545 rc = avc_has_perm(sid, sid, SECCLASS_MEMPROTECT,
3546 MEMPROTECT__MMAP_ZERO, NULL);
3547 }
3548
3549 return rc;
3550}
3551
3552static int selinux_mmap_file(struct file *file, unsigned long reqprot,
3553 unsigned long prot, unsigned long flags)
3554{
3555 if (selinux_checkreqprot)
3556 prot = reqprot;
3557
3558 return file_map_prot_check(file, prot,
3559 (flags & MAP_TYPE) == MAP_SHARED);
3560}
3561
3562static int selinux_file_mprotect(struct vm_area_struct *vma,
3563 unsigned long reqprot,
3564 unsigned long prot)
3565{
3566 const struct cred *cred = current_cred();
3567
3568 if (selinux_checkreqprot)
3569 prot = reqprot;
3570
3571 if (default_noexec &&
3572 (prot & PROT_EXEC) && !(vma->vm_flags & VM_EXEC)) {
3573 int rc = 0;
3574 if (vma->vm_start >= vma->vm_mm->start_brk &&
3575 vma->vm_end <= vma->vm_mm->brk) {
3576 rc = cred_has_perm(cred, cred, PROCESS__EXECHEAP);
3577 } else if (!vma->vm_file &&
3578 ((vma->vm_start <= vma->vm_mm->start_stack &&
3579 vma->vm_end >= vma->vm_mm->start_stack) ||
3580 vma_is_stack_for_current(vma))) {
3581 rc = current_has_perm(current, PROCESS__EXECSTACK);
3582 } else if (vma->vm_file && vma->anon_vma) {
3583 /*
3584 * We are making executable a file mapping that has
3585 * had some COW done. Since pages might have been
3586 * written, check ability to execute the possibly
3587 * modified content. This typically should only
3588 * occur for text relocations.
3589 */
3590 rc = file_has_perm(cred, vma->vm_file, FILE__EXECMOD);
3591 }
3592 if (rc)
3593 return rc;
3594 }
3595
3596 return file_map_prot_check(vma->vm_file, prot, vma->vm_flags&VM_SHARED);
3597}
3598
3599static int selinux_file_lock(struct file *file, unsigned int cmd)
3600{
3601 const struct cred *cred = current_cred();
3602
3603 return file_has_perm(cred, file, FILE__LOCK);
3604}
3605
3606static int selinux_file_fcntl(struct file *file, unsigned int cmd,
3607 unsigned long arg)
3608{
3609 const struct cred *cred = current_cred();
3610 int err = 0;
3611
3612 switch (cmd) {
3613 case F_SETFL:
3614 if ((file->f_flags & O_APPEND) && !(arg & O_APPEND)) {
3615 err = file_has_perm(cred, file, FILE__WRITE);
3616 break;
3617 }
3618 /* fall through */
3619 case F_SETOWN:
3620 case F_SETSIG:
3621 case F_GETFL:
3622 case F_GETOWN:
3623 case F_GETSIG:
3624 case F_GETOWNER_UIDS:
3625 /* Just check FD__USE permission */
3626 err = file_has_perm(cred, file, 0);
3627 break;
3628 case F_GETLK:
3629 case F_SETLK:
3630 case F_SETLKW:
3631 case F_OFD_GETLK:
3632 case F_OFD_SETLK:
3633 case F_OFD_SETLKW:
3634#if BITS_PER_LONG == 32
3635 case F_GETLK64:
3636 case F_SETLK64:
3637 case F_SETLKW64:
3638#endif
3639 err = file_has_perm(cred, file, FILE__LOCK);
3640 break;
3641 }
3642
3643 return err;
3644}
3645
3646static void selinux_file_set_fowner(struct file *file)
3647{
3648 struct file_security_struct *fsec;
3649
3650 fsec = file->f_security;
3651 fsec->fown_sid = current_sid();
3652}
3653
3654static int selinux_file_send_sigiotask(struct task_struct *tsk,
3655 struct fown_struct *fown, int signum)
3656{
3657 struct file *file;
3658 u32 sid = task_sid(tsk);
3659 u32 perm;
3660 struct file_security_struct *fsec;
3661
3662 /* struct fown_struct is never outside the context of a struct file */
3663 file = container_of(fown, struct file, f_owner);
3664
3665 fsec = file->f_security;
3666
3667 if (!signum)
3668 perm = signal_to_av(SIGIO); /* as per send_sigio_to_task */
3669 else
3670 perm = signal_to_av(signum);
3671
3672 return avc_has_perm(fsec->fown_sid, sid,
3673 SECCLASS_PROCESS, perm, NULL);
3674}
3675
3676static int selinux_file_receive(struct file *file)
3677{
3678 const struct cred *cred = current_cred();
3679
3680 return file_has_perm(cred, file, file_to_av(file));
3681}
3682
3683static int selinux_file_open(struct file *file, const struct cred *cred)
3684{
3685 struct file_security_struct *fsec;
3686 struct inode_security_struct *isec;
3687
3688 fsec = file->f_security;
3689 isec = inode_security(file_inode(file));
3690 /*
3691 * Save inode label and policy sequence number
3692 * at open-time so that selinux_file_permission
3693 * can determine whether revalidation is necessary.
3694 * Task label is already saved in the file security
3695 * struct as its SID.
3696 */
3697 fsec->isid = isec->sid;
3698 fsec->pseqno = avc_policy_seqno();
3699 /*
3700 * Since the inode label or policy seqno may have changed
3701 * between the selinux_inode_permission check and the saving
3702 * of state above, recheck that access is still permitted.
3703 * Otherwise, access might never be revalidated against the
3704 * new inode label or new policy.
3705 * This check is not redundant - do not remove.
3706 */
3707 return file_path_has_perm(cred, file, open_file_to_av(file));
3708}
3709
3710/* task security operations */
3711
3712static int selinux_task_create(unsigned long clone_flags)
3713{
3714 return current_has_perm(current, PROCESS__FORK);
3715}
3716
3717/*
3718 * allocate the SELinux part of blank credentials
3719 */
3720static int selinux_cred_alloc_blank(struct cred *cred, gfp_t gfp)
3721{
3722 struct task_security_struct *tsec;
3723
3724 tsec = kzalloc(sizeof(struct task_security_struct), gfp);
3725 if (!tsec)
3726 return -ENOMEM;
3727
3728 cred->security = tsec;
3729 return 0;
3730}
3731
3732/*
3733 * detach and free the LSM part of a set of credentials
3734 */
3735static void selinux_cred_free(struct cred *cred)
3736{
3737 struct task_security_struct *tsec = cred->security;
3738
3739 /*
3740 * cred->security == NULL if security_cred_alloc_blank() or
3741 * security_prepare_creds() returned an error.
3742 */
3743 BUG_ON(cred->security && (unsigned long) cred->security < PAGE_SIZE);
3744 cred->security = (void *) 0x7UL;
3745 kfree(tsec);
3746}
3747
3748/*
3749 * prepare a new set of credentials for modification
3750 */
3751static int selinux_cred_prepare(struct cred *new, const struct cred *old,
3752 gfp_t gfp)
3753{
3754 const struct task_security_struct *old_tsec;
3755 struct task_security_struct *tsec;
3756
3757 old_tsec = old->security;
3758
3759 tsec = kmemdup(old_tsec, sizeof(struct task_security_struct), gfp);
3760 if (!tsec)
3761 return -ENOMEM;
3762
3763 new->security = tsec;
3764 return 0;
3765}
3766
3767/*
3768 * transfer the SELinux data to a blank set of creds
3769 */
3770static void selinux_cred_transfer(struct cred *new, const struct cred *old)
3771{
3772 const struct task_security_struct *old_tsec = old->security;
3773 struct task_security_struct *tsec = new->security;
3774
3775 *tsec = *old_tsec;
3776}
3777
3778/*
3779 * set the security data for a kernel service
3780 * - all the creation contexts are set to unlabelled
3781 */
3782static int selinux_kernel_act_as(struct cred *new, u32 secid)
3783{
3784 struct task_security_struct *tsec = new->security;
3785 u32 sid = current_sid();
3786 int ret;
3787
3788 ret = avc_has_perm(sid, secid,
3789 SECCLASS_KERNEL_SERVICE,
3790 KERNEL_SERVICE__USE_AS_OVERRIDE,
3791 NULL);
3792 if (ret == 0) {
3793 tsec->sid = secid;
3794 tsec->create_sid = 0;
3795 tsec->keycreate_sid = 0;
3796 tsec->sockcreate_sid = 0;
3797 }
3798 return ret;
3799}
3800
3801/*
3802 * set the file creation context in a security record to the same as the
3803 * objective context of the specified inode
3804 */
3805static int selinux_kernel_create_files_as(struct cred *new, struct inode *inode)
3806{
3807 struct inode_security_struct *isec = inode_security(inode);
3808 struct task_security_struct *tsec = new->security;
3809 u32 sid = current_sid();
3810 int ret;
3811
3812 ret = avc_has_perm(sid, isec->sid,
3813 SECCLASS_KERNEL_SERVICE,
3814 KERNEL_SERVICE__CREATE_FILES_AS,
3815 NULL);
3816
3817 if (ret == 0)
3818 tsec->create_sid = isec->sid;
3819 return ret;
3820}
3821
3822static int selinux_kernel_module_request(char *kmod_name)
3823{
3824 u32 sid;
3825 struct common_audit_data ad;
3826
3827 sid = task_sid(current);
3828
3829 ad.type = LSM_AUDIT_DATA_KMOD;
3830 ad.u.kmod_name = kmod_name;
3831
3832 return avc_has_perm(sid, SECINITSID_KERNEL, SECCLASS_SYSTEM,
3833 SYSTEM__MODULE_REQUEST, &ad);
3834}
3835
3836static int selinux_kernel_module_from_file(struct file *file)
3837{
3838 struct common_audit_data ad;
3839 struct inode_security_struct *isec;
3840 struct file_security_struct *fsec;
3841 u32 sid = current_sid();
3842 int rc;
3843
3844 /* init_module */
3845 if (file == NULL)
3846 return avc_has_perm(sid, sid, SECCLASS_SYSTEM,
3847 SYSTEM__MODULE_LOAD, NULL);
3848
3849 /* finit_module */
3850
3851 ad.type = LSM_AUDIT_DATA_FILE;
3852 ad.u.file = file;
3853
3854 fsec = file->f_security;
3855 if (sid != fsec->sid) {
3856 rc = avc_has_perm(sid, fsec->sid, SECCLASS_FD, FD__USE, &ad);
3857 if (rc)
3858 return rc;
3859 }
3860
3861 isec = inode_security(file_inode(file));
3862 return avc_has_perm(sid, isec->sid, SECCLASS_SYSTEM,
3863 SYSTEM__MODULE_LOAD, &ad);
3864}
3865
3866static int selinux_kernel_read_file(struct file *file,
3867 enum kernel_read_file_id id)
3868{
3869 int rc = 0;
3870
3871 switch (id) {
3872 case READING_MODULE:
3873 rc = selinux_kernel_module_from_file(file);
3874 break;
3875 default:
3876 break;
3877 }
3878
3879 return rc;
3880}
3881
3882static int selinux_task_setpgid(struct task_struct *p, pid_t pgid)
3883{
3884 return current_has_perm(p, PROCESS__SETPGID);
3885}
3886
3887static int selinux_task_getpgid(struct task_struct *p)
3888{
3889 return current_has_perm(p, PROCESS__GETPGID);
3890}
3891
3892static int selinux_task_getsid(struct task_struct *p)
3893{
3894 return current_has_perm(p, PROCESS__GETSESSION);
3895}
3896
3897static void selinux_task_getsecid(struct task_struct *p, u32 *secid)
3898{
3899 *secid = task_sid(p);
3900}
3901
3902static int selinux_task_setnice(struct task_struct *p, int nice)
3903{
3904 return current_has_perm(p, PROCESS__SETSCHED);
3905}
3906
3907static int selinux_task_setioprio(struct task_struct *p, int ioprio)
3908{
3909 return current_has_perm(p, PROCESS__SETSCHED);
3910}
3911
3912static int selinux_task_getioprio(struct task_struct *p)
3913{
3914 return current_has_perm(p, PROCESS__GETSCHED);
3915}
3916
3917static int selinux_task_setrlimit(struct task_struct *p, unsigned int resource,
3918 struct rlimit *new_rlim)
3919{
3920 struct rlimit *old_rlim = p->signal->rlim + resource;
3921
3922 /* Control the ability to change the hard limit (whether
3923 lowering or raising it), so that the hard limit can
3924 later be used as a safe reset point for the soft limit
3925 upon context transitions. See selinux_bprm_committing_creds. */
3926 if (old_rlim->rlim_max != new_rlim->rlim_max)
3927 return current_has_perm(p, PROCESS__SETRLIMIT);
3928
3929 return 0;
3930}
3931
3932static int selinux_task_setscheduler(struct task_struct *p)
3933{
3934 return current_has_perm(p, PROCESS__SETSCHED);
3935}
3936
3937static int selinux_task_getscheduler(struct task_struct *p)
3938{
3939 return current_has_perm(p, PROCESS__GETSCHED);
3940}
3941
3942static int selinux_task_movememory(struct task_struct *p)
3943{
3944 return current_has_perm(p, PROCESS__SETSCHED);
3945}
3946
3947static int selinux_task_kill(struct task_struct *p, struct siginfo *info,
3948 int sig, u32 secid)
3949{
3950 u32 perm;
3951 int rc;
3952
3953 if (!sig)
3954 perm = PROCESS__SIGNULL; /* null signal; existence test */
3955 else
3956 perm = signal_to_av(sig);
3957 if (secid)
3958 rc = avc_has_perm(secid, task_sid(p),
3959 SECCLASS_PROCESS, perm, NULL);
3960 else
3961 rc = current_has_perm(p, perm);
3962 return rc;
3963}
3964
3965static int selinux_task_wait(struct task_struct *p)
3966{
3967 return task_has_perm(p, current, PROCESS__SIGCHLD);
3968}
3969
3970static void selinux_task_to_inode(struct task_struct *p,
3971 struct inode *inode)
3972{
3973 struct inode_security_struct *isec = inode->i_security;
3974 u32 sid = task_sid(p);
3975
3976 spin_lock(&isec->lock);
3977 isec->sclass = inode_mode_to_security_class(inode->i_mode);
3978 isec->sid = sid;
3979 isec->initialized = LABEL_INITIALIZED;
3980 spin_unlock(&isec->lock);
3981}
3982
3983/* Returns error only if unable to parse addresses */
3984static int selinux_parse_skb_ipv4(struct sk_buff *skb,
3985 struct common_audit_data *ad, u8 *proto)
3986{
3987 int offset, ihlen, ret = -EINVAL;
3988 struct iphdr _iph, *ih;
3989
3990 offset = skb_network_offset(skb);
3991 ih = skb_header_pointer(skb, offset, sizeof(_iph), &_iph);
3992 if (ih == NULL)
3993 goto out;
3994
3995 ihlen = ih->ihl * 4;
3996 if (ihlen < sizeof(_iph))
3997 goto out;
3998
3999 ad->u.net->v4info.saddr = ih->saddr;
4000 ad->u.net->v4info.daddr = ih->daddr;
4001 ret = 0;
4002
4003 if (proto)
4004 *proto = ih->protocol;
4005
4006 switch (ih->protocol) {
4007 case IPPROTO_TCP: {
4008 struct tcphdr _tcph, *th;
4009
4010 if (ntohs(ih->frag_off) & IP_OFFSET)
4011 break;
4012
4013 offset += ihlen;
4014 th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph);
4015 if (th == NULL)
4016 break;
4017
4018 ad->u.net->sport = th->source;
4019 ad->u.net->dport = th->dest;
4020 break;
4021 }
4022
4023 case IPPROTO_UDP: {
4024 struct udphdr _udph, *uh;
4025
4026 if (ntohs(ih->frag_off) & IP_OFFSET)
4027 break;
4028
4029 offset += ihlen;
4030 uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph);
4031 if (uh == NULL)
4032 break;
4033
4034 ad->u.net->sport = uh->source;
4035 ad->u.net->dport = uh->dest;
4036 break;
4037 }
4038
4039 case IPPROTO_DCCP: {
4040 struct dccp_hdr _dccph, *dh;
4041
4042 if (ntohs(ih->frag_off) & IP_OFFSET)
4043 break;
4044
4045 offset += ihlen;
4046 dh = skb_header_pointer(skb, offset, sizeof(_dccph), &_dccph);
4047 if (dh == NULL)
4048 break;
4049
4050 ad->u.net->sport = dh->dccph_sport;
4051 ad->u.net->dport = dh->dccph_dport;
4052 break;
4053 }
4054
4055 default:
4056 break;
4057 }
4058out:
4059 return ret;
4060}
4061
4062#if IS_ENABLED(CONFIG_IPV6)
4063
4064/* Returns error only if unable to parse addresses */
4065static int selinux_parse_skb_ipv6(struct sk_buff *skb,
4066 struct common_audit_data *ad, u8 *proto)
4067{
4068 u8 nexthdr;
4069 int ret = -EINVAL, offset;
4070 struct ipv6hdr _ipv6h, *ip6;
4071 __be16 frag_off;
4072
4073 offset = skb_network_offset(skb);
4074 ip6 = skb_header_pointer(skb, offset, sizeof(_ipv6h), &_ipv6h);
4075 if (ip6 == NULL)
4076 goto out;
4077
4078 ad->u.net->v6info.saddr = ip6->saddr;
4079 ad->u.net->v6info.daddr = ip6->daddr;
4080 ret = 0;
4081
4082 nexthdr = ip6->nexthdr;
4083 offset += sizeof(_ipv6h);
4084 offset = ipv6_skip_exthdr(skb, offset, &nexthdr, &frag_off);
4085 if (offset < 0)
4086 goto out;
4087
4088 if (proto)
4089 *proto = nexthdr;
4090
4091 switch (nexthdr) {
4092 case IPPROTO_TCP: {
4093 struct tcphdr _tcph, *th;
4094
4095 th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph);
4096 if (th == NULL)
4097 break;
4098
4099 ad->u.net->sport = th->source;
4100 ad->u.net->dport = th->dest;
4101 break;
4102 }
4103
4104 case IPPROTO_UDP: {
4105 struct udphdr _udph, *uh;
4106
4107 uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph);
4108 if (uh == NULL)
4109 break;
4110
4111 ad->u.net->sport = uh->source;
4112 ad->u.net->dport = uh->dest;
4113 break;
4114 }
4115
4116 case IPPROTO_DCCP: {
4117 struct dccp_hdr _dccph, *dh;
4118
4119 dh = skb_header_pointer(skb, offset, sizeof(_dccph), &_dccph);
4120 if (dh == NULL)
4121 break;
4122
4123 ad->u.net->sport = dh->dccph_sport;
4124 ad->u.net->dport = dh->dccph_dport;
4125 break;
4126 }
4127
4128 /* includes fragments */
4129 default:
4130 break;
4131 }
4132out:
4133 return ret;
4134}
4135
4136#endif /* IPV6 */
4137
4138static int selinux_parse_skb(struct sk_buff *skb, struct common_audit_data *ad,
4139 char **_addrp, int src, u8 *proto)
4140{
4141 char *addrp;
4142 int ret;
4143
4144 switch (ad->u.net->family) {
4145 case PF_INET:
4146 ret = selinux_parse_skb_ipv4(skb, ad, proto);
4147 if (ret)
4148 goto parse_error;
4149 addrp = (char *)(src ? &ad->u.net->v4info.saddr :
4150 &ad->u.net->v4info.daddr);
4151 goto okay;
4152
4153#if IS_ENABLED(CONFIG_IPV6)
4154 case PF_INET6:
4155 ret = selinux_parse_skb_ipv6(skb, ad, proto);
4156 if (ret)
4157 goto parse_error;
4158 addrp = (char *)(src ? &ad->u.net->v6info.saddr :
4159 &ad->u.net->v6info.daddr);
4160 goto okay;
4161#endif /* IPV6 */
4162 default:
4163 addrp = NULL;
4164 goto okay;
4165 }
4166
4167parse_error:
4168 printk(KERN_WARNING
4169 "SELinux: failure in selinux_parse_skb(),"
4170 " unable to parse packet\n");
4171 return ret;
4172
4173okay:
4174 if (_addrp)
4175 *_addrp = addrp;
4176 return 0;
4177}
4178
4179/**
4180 * selinux_skb_peerlbl_sid - Determine the peer label of a packet
4181 * @skb: the packet
4182 * @family: protocol family
4183 * @sid: the packet's peer label SID
4184 *
4185 * Description:
4186 * Check the various different forms of network peer labeling and determine
4187 * the peer label/SID for the packet; most of the magic actually occurs in
4188 * the security server function security_net_peersid_cmp(). The function
4189 * returns zero if the value in @sid is valid (although it may be SECSID_NULL)
4190 * or -EACCES if @sid is invalid due to inconsistencies with the different
4191 * peer labels.
4192 *
4193 */
4194static int selinux_skb_peerlbl_sid(struct sk_buff *skb, u16 family, u32 *sid)
4195{
4196 int err;
4197 u32 xfrm_sid;
4198 u32 nlbl_sid;
4199 u32 nlbl_type;
4200
4201 err = selinux_xfrm_skb_sid(skb, &xfrm_sid);
4202 if (unlikely(err))
4203 return -EACCES;
4204 err = selinux_netlbl_skbuff_getsid(skb, family, &nlbl_type, &nlbl_sid);
4205 if (unlikely(err))
4206 return -EACCES;
4207
4208 err = security_net_peersid_resolve(nlbl_sid, nlbl_type, xfrm_sid, sid);
4209 if (unlikely(err)) {
4210 printk(KERN_WARNING
4211 "SELinux: failure in selinux_skb_peerlbl_sid(),"
4212 " unable to determine packet's peer label\n");
4213 return -EACCES;
4214 }
4215
4216 return 0;
4217}
4218
4219/**
4220 * selinux_conn_sid - Determine the child socket label for a connection
4221 * @sk_sid: the parent socket's SID
4222 * @skb_sid: the packet's SID
4223 * @conn_sid: the resulting connection SID
4224 *
4225 * If @skb_sid is valid then the user:role:type information from @sk_sid is
4226 * combined with the MLS information from @skb_sid in order to create
4227 * @conn_sid. If @skb_sid is not valid then then @conn_sid is simply a copy
4228 * of @sk_sid. Returns zero on success, negative values on failure.
4229 *
4230 */
4231static int selinux_conn_sid(u32 sk_sid, u32 skb_sid, u32 *conn_sid)
4232{
4233 int err = 0;
4234
4235 if (skb_sid != SECSID_NULL)
4236 err = security_sid_mls_copy(sk_sid, skb_sid, conn_sid);
4237 else
4238 *conn_sid = sk_sid;
4239
4240 return err;
4241}
4242
4243/* socket security operations */
4244
4245static int socket_sockcreate_sid(const struct task_security_struct *tsec,
4246 u16 secclass, u32 *socksid)
4247{
4248 if (tsec->sockcreate_sid > SECSID_NULL) {
4249 *socksid = tsec->sockcreate_sid;
4250 return 0;
4251 }
4252
4253 return security_transition_sid(tsec->sid, tsec->sid, secclass, NULL,
4254 socksid);
4255}
4256
4257static int sock_has_perm(struct task_struct *task, struct sock *sk, u32 perms)
4258{
4259 struct sk_security_struct *sksec = sk->sk_security;
4260 struct common_audit_data ad;
4261 struct lsm_network_audit net = {0,};
4262 u32 tsid = task_sid(task);
4263
4264 if (sksec->sid == SECINITSID_KERNEL)
4265 return 0;
4266
4267 ad.type = LSM_AUDIT_DATA_NET;
4268 ad.u.net = &net;
4269 ad.u.net->sk = sk;
4270
4271 return avc_has_perm(tsid, sksec->sid, sksec->sclass, perms, &ad);
4272}
4273
4274static int selinux_socket_create(int family, int type,
4275 int protocol, int kern)
4276{
4277 const struct task_security_struct *tsec = current_security();
4278 u32 newsid;
4279 u16 secclass;
4280 int rc;
4281
4282 if (kern)
4283 return 0;
4284
4285 secclass = socket_type_to_security_class(family, type, protocol);
4286 rc = socket_sockcreate_sid(tsec, secclass, &newsid);
4287 if (rc)
4288 return rc;
4289
4290 return avc_has_perm(tsec->sid, newsid, secclass, SOCKET__CREATE, NULL);
4291}
4292
4293static int selinux_socket_post_create(struct socket *sock, int family,
4294 int type, int protocol, int kern)
4295{
4296 const struct task_security_struct *tsec = current_security();
4297 struct inode_security_struct *isec = inode_security_novalidate(SOCK_INODE(sock));
4298 struct sk_security_struct *sksec;
4299 u16 sclass = socket_type_to_security_class(family, type, protocol);
4300 u32 sid = SECINITSID_KERNEL;
4301 int err = 0;
4302
4303 if (!kern) {
4304 err = socket_sockcreate_sid(tsec, sclass, &sid);
4305 if (err)
4306 return err;
4307 }
4308
4309 isec->sclass = sclass;
4310 isec->sid = sid;
4311 isec->initialized = LABEL_INITIALIZED;
4312
4313 if (sock->sk) {
4314 sksec = sock->sk->sk_security;
4315 sksec->sclass = sclass;
4316 sksec->sid = sid;
4317 err = selinux_netlbl_socket_post_create(sock->sk, family);
4318 }
4319
4320 return err;
4321}
4322
4323/* Range of port numbers used to automatically bind.
4324 Need to determine whether we should perform a name_bind
4325 permission check between the socket and the port number. */
4326
4327static int selinux_socket_bind(struct socket *sock, struct sockaddr *address, int addrlen)
4328{
4329 struct sock *sk = sock->sk;
4330 u16 family;
4331 int err;
4332
4333 err = sock_has_perm(current, sk, SOCKET__BIND);
4334 if (err)
4335 goto out;
4336
4337 /*
4338 * If PF_INET or PF_INET6, check name_bind permission for the port.
4339 * Multiple address binding for SCTP is not supported yet: we just
4340 * check the first address now.
4341 */
4342 family = sk->sk_family;
4343 if (family == PF_INET || family == PF_INET6) {
4344 char *addrp;
4345 struct sk_security_struct *sksec = sk->sk_security;
4346 struct common_audit_data ad;
4347 struct lsm_network_audit net = {0,};
4348 struct sockaddr_in *addr4 = NULL;
4349 struct sockaddr_in6 *addr6 = NULL;
4350 unsigned short snum;
4351 u32 sid, node_perm;
4352
4353 if (family == PF_INET) {
4354 addr4 = (struct sockaddr_in *)address;
4355 snum = ntohs(addr4->sin_port);
4356 addrp = (char *)&addr4->sin_addr.s_addr;
4357 } else {
4358 addr6 = (struct sockaddr_in6 *)address;
4359 snum = ntohs(addr6->sin6_port);
4360 addrp = (char *)&addr6->sin6_addr.s6_addr;
4361 }
4362
4363 if (snum) {
4364 int low, high;
4365
4366 inet_get_local_port_range(sock_net(sk), &low, &high);
4367
4368 if (snum < max(PROT_SOCK, low) || snum > high) {
4369 err = sel_netport_sid(sk->sk_protocol,
4370 snum, &sid);
4371 if (err)
4372 goto out;
4373 ad.type = LSM_AUDIT_DATA_NET;
4374 ad.u.net = &net;
4375 ad.u.net->sport = htons(snum);
4376 ad.u.net->family = family;
4377 err = avc_has_perm(sksec->sid, sid,
4378 sksec->sclass,
4379 SOCKET__NAME_BIND, &ad);
4380 if (err)
4381 goto out;
4382 }
4383 }
4384
4385 switch (sksec->sclass) {
4386 case SECCLASS_TCP_SOCKET:
4387 node_perm = TCP_SOCKET__NODE_BIND;
4388 break;
4389
4390 case SECCLASS_UDP_SOCKET:
4391 node_perm = UDP_SOCKET__NODE_BIND;
4392 break;
4393
4394 case SECCLASS_DCCP_SOCKET:
4395 node_perm = DCCP_SOCKET__NODE_BIND;
4396 break;
4397
4398 default:
4399 node_perm = RAWIP_SOCKET__NODE_BIND;
4400 break;
4401 }
4402
4403 err = sel_netnode_sid(addrp, family, &sid);
4404 if (err)
4405 goto out;
4406
4407 ad.type = LSM_AUDIT_DATA_NET;
4408 ad.u.net = &net;
4409 ad.u.net->sport = htons(snum);
4410 ad.u.net->family = family;
4411
4412 if (family == PF_INET)
4413 ad.u.net->v4info.saddr = addr4->sin_addr.s_addr;
4414 else
4415 ad.u.net->v6info.saddr = addr6->sin6_addr;
4416
4417 err = avc_has_perm(sksec->sid, sid,
4418 sksec->sclass, node_perm, &ad);
4419 if (err)
4420 goto out;
4421 }
4422out:
4423 return err;
4424}
4425
4426static int selinux_socket_connect(struct socket *sock, struct sockaddr *address, int addrlen)
4427{
4428 struct sock *sk = sock->sk;
4429 struct sk_security_struct *sksec = sk->sk_security;
4430 int err;
4431
4432 err = sock_has_perm(current, sk, SOCKET__CONNECT);
4433 if (err)
4434 return err;
4435
4436 /*
4437 * If a TCP or DCCP socket, check name_connect permission for the port.
4438 */
4439 if (sksec->sclass == SECCLASS_TCP_SOCKET ||
4440 sksec->sclass == SECCLASS_DCCP_SOCKET) {
4441 struct common_audit_data ad;
4442 struct lsm_network_audit net = {0,};
4443 struct sockaddr_in *addr4 = NULL;
4444 struct sockaddr_in6 *addr6 = NULL;
4445 unsigned short snum;
4446 u32 sid, perm;
4447
4448 if (sk->sk_family == PF_INET) {
4449 addr4 = (struct sockaddr_in *)address;
4450 if (addrlen < sizeof(struct sockaddr_in))
4451 return -EINVAL;
4452 snum = ntohs(addr4->sin_port);
4453 } else {
4454 addr6 = (struct sockaddr_in6 *)address;
4455 if (addrlen < SIN6_LEN_RFC2133)
4456 return -EINVAL;
4457 snum = ntohs(addr6->sin6_port);
4458 }
4459
4460 err = sel_netport_sid(sk->sk_protocol, snum, &sid);
4461 if (err)
4462 goto out;
4463
4464 perm = (sksec->sclass == SECCLASS_TCP_SOCKET) ?
4465 TCP_SOCKET__NAME_CONNECT : DCCP_SOCKET__NAME_CONNECT;
4466
4467 ad.type = LSM_AUDIT_DATA_NET;
4468 ad.u.net = &net;
4469 ad.u.net->dport = htons(snum);
4470 ad.u.net->family = sk->sk_family;
4471 err = avc_has_perm(sksec->sid, sid, sksec->sclass, perm, &ad);
4472 if (err)
4473 goto out;
4474 }
4475
4476 err = selinux_netlbl_socket_connect(sk, address);
4477
4478out:
4479 return err;
4480}
4481
4482static int selinux_socket_listen(struct socket *sock, int backlog)
4483{
4484 return sock_has_perm(current, sock->sk, SOCKET__LISTEN);
4485}
4486
4487static int selinux_socket_accept(struct socket *sock, struct socket *newsock)
4488{
4489 int err;
4490 struct inode_security_struct *isec;
4491 struct inode_security_struct *newisec;
4492 u16 sclass;
4493 u32 sid;
4494
4495 err = sock_has_perm(current, sock->sk, SOCKET__ACCEPT);
4496 if (err)
4497 return err;
4498
4499 isec = inode_security_novalidate(SOCK_INODE(sock));
4500 spin_lock(&isec->lock);
4501 sclass = isec->sclass;
4502 sid = isec->sid;
4503 spin_unlock(&isec->lock);
4504
4505 newisec = inode_security_novalidate(SOCK_INODE(newsock));
4506 newisec->sclass = sclass;
4507 newisec->sid = sid;
4508 newisec->initialized = LABEL_INITIALIZED;
4509
4510 return 0;
4511}
4512
4513static int selinux_socket_sendmsg(struct socket *sock, struct msghdr *msg,
4514 int size)
4515{
4516 return sock_has_perm(current, sock->sk, SOCKET__WRITE);
4517}
4518
4519static int selinux_socket_recvmsg(struct socket *sock, struct msghdr *msg,
4520 int size, int flags)
4521{
4522 return sock_has_perm(current, sock->sk, SOCKET__READ);
4523}
4524
4525static int selinux_socket_getsockname(struct socket *sock)
4526{
4527 return sock_has_perm(current, sock->sk, SOCKET__GETATTR);
4528}
4529
4530static int selinux_socket_getpeername(struct socket *sock)
4531{
4532 return sock_has_perm(current, sock->sk, SOCKET__GETATTR);
4533}
4534
4535static int selinux_socket_setsockopt(struct socket *sock, int level, int optname)
4536{
4537 int err;
4538
4539 err = sock_has_perm(current, sock->sk, SOCKET__SETOPT);
4540 if (err)
4541 return err;
4542
4543 return selinux_netlbl_socket_setsockopt(sock, level, optname);
4544}
4545
4546static int selinux_socket_getsockopt(struct socket *sock, int level,
4547 int optname)
4548{
4549 return sock_has_perm(current, sock->sk, SOCKET__GETOPT);
4550}
4551
4552static int selinux_socket_shutdown(struct socket *sock, int how)
4553{
4554 return sock_has_perm(current, sock->sk, SOCKET__SHUTDOWN);
4555}
4556
4557static int selinux_socket_unix_stream_connect(struct sock *sock,
4558 struct sock *other,
4559 struct sock *newsk)
4560{
4561 struct sk_security_struct *sksec_sock = sock->sk_security;
4562 struct sk_security_struct *sksec_other = other->sk_security;
4563 struct sk_security_struct *sksec_new = newsk->sk_security;
4564 struct common_audit_data ad;
4565 struct lsm_network_audit net = {0,};
4566 int err;
4567
4568 ad.type = LSM_AUDIT_DATA_NET;
4569 ad.u.net = &net;
4570 ad.u.net->sk = other;
4571
4572 err = avc_has_perm(sksec_sock->sid, sksec_other->sid,
4573 sksec_other->sclass,
4574 UNIX_STREAM_SOCKET__CONNECTTO, &ad);
4575 if (err)
4576 return err;
4577
4578 /* server child socket */
4579 sksec_new->peer_sid = sksec_sock->sid;
4580 err = security_sid_mls_copy(sksec_other->sid, sksec_sock->sid,
4581 &sksec_new->sid);
4582 if (err)
4583 return err;
4584
4585 /* connecting socket */
4586 sksec_sock->peer_sid = sksec_new->sid;
4587
4588 return 0;
4589}
4590
4591static int selinux_socket_unix_may_send(struct socket *sock,
4592 struct socket *other)
4593{
4594 struct sk_security_struct *ssec = sock->sk->sk_security;
4595 struct sk_security_struct *osec = other->sk->sk_security;
4596 struct common_audit_data ad;
4597 struct lsm_network_audit net = {0,};
4598
4599 ad.type = LSM_AUDIT_DATA_NET;
4600 ad.u.net = &net;
4601 ad.u.net->sk = other->sk;
4602
4603 return avc_has_perm(ssec->sid, osec->sid, osec->sclass, SOCKET__SENDTO,
4604 &ad);
4605}
4606
4607static int selinux_inet_sys_rcv_skb(struct net *ns, int ifindex,
4608 char *addrp, u16 family, u32 peer_sid,
4609 struct common_audit_data *ad)
4610{
4611 int err;
4612 u32 if_sid;
4613 u32 node_sid;
4614
4615 err = sel_netif_sid(ns, ifindex, &if_sid);
4616 if (err)
4617 return err;
4618 err = avc_has_perm(peer_sid, if_sid,
4619 SECCLASS_NETIF, NETIF__INGRESS, ad);
4620 if (err)
4621 return err;
4622
4623 err = sel_netnode_sid(addrp, family, &node_sid);
4624 if (err)
4625 return err;
4626 return avc_has_perm(peer_sid, node_sid,
4627 SECCLASS_NODE, NODE__RECVFROM, ad);
4628}
4629
4630static int selinux_sock_rcv_skb_compat(struct sock *sk, struct sk_buff *skb,
4631 u16 family)
4632{
4633 int err = 0;
4634 struct sk_security_struct *sksec = sk->sk_security;
4635 u32 sk_sid = sksec->sid;
4636 struct common_audit_data ad;
4637 struct lsm_network_audit net = {0,};
4638 char *addrp;
4639
4640 ad.type = LSM_AUDIT_DATA_NET;
4641 ad.u.net = &net;
4642 ad.u.net->netif = skb->skb_iif;
4643 ad.u.net->family = family;
4644 err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL);
4645 if (err)
4646 return err;
4647
4648 if (selinux_secmark_enabled()) {
4649 err = avc_has_perm(sk_sid, skb->secmark, SECCLASS_PACKET,
4650 PACKET__RECV, &ad);
4651 if (err)
4652 return err;
4653 }
4654
4655 err = selinux_netlbl_sock_rcv_skb(sksec, skb, family, &ad);
4656 if (err)
4657 return err;
4658 err = selinux_xfrm_sock_rcv_skb(sksec->sid, skb, &ad);
4659
4660 return err;
4661}
4662
4663static int selinux_socket_sock_rcv_skb(struct sock *sk, struct sk_buff *skb)
4664{
4665 int err;
4666 struct sk_security_struct *sksec = sk->sk_security;
4667 u16 family = sk->sk_family;
4668 u32 sk_sid = sksec->sid;
4669 struct common_audit_data ad;
4670 struct lsm_network_audit net = {0,};
4671 char *addrp;
4672 u8 secmark_active;
4673 u8 peerlbl_active;
4674
4675 if (family != PF_INET && family != PF_INET6)
4676 return 0;
4677
4678 /* Handle mapped IPv4 packets arriving via IPv6 sockets */
4679 if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
4680 family = PF_INET;
4681
4682 /* If any sort of compatibility mode is enabled then handoff processing
4683 * to the selinux_sock_rcv_skb_compat() function to deal with the
4684 * special handling. We do this in an attempt to keep this function
4685 * as fast and as clean as possible. */
4686 if (!selinux_policycap_netpeer)
4687 return selinux_sock_rcv_skb_compat(sk, skb, family);
4688
4689 secmark_active = selinux_secmark_enabled();
4690 peerlbl_active = selinux_peerlbl_enabled();
4691 if (!secmark_active && !peerlbl_active)
4692 return 0;
4693
4694 ad.type = LSM_AUDIT_DATA_NET;
4695 ad.u.net = &net;
4696 ad.u.net->netif = skb->skb_iif;
4697 ad.u.net->family = family;
4698 err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL);
4699 if (err)
4700 return err;
4701
4702 if (peerlbl_active) {
4703 u32 peer_sid;
4704
4705 err = selinux_skb_peerlbl_sid(skb, family, &peer_sid);
4706 if (err)
4707 return err;
4708 err = selinux_inet_sys_rcv_skb(sock_net(sk), skb->skb_iif,
4709 addrp, family, peer_sid, &ad);
4710 if (err) {
4711 selinux_netlbl_err(skb, family, err, 0);
4712 return err;
4713 }
4714 err = avc_has_perm(sk_sid, peer_sid, SECCLASS_PEER,
4715 PEER__RECV, &ad);
4716 if (err) {
4717 selinux_netlbl_err(skb, family, err, 0);
4718 return err;
4719 }
4720 }
4721
4722 if (secmark_active) {
4723 err = avc_has_perm(sk_sid, skb->secmark, SECCLASS_PACKET,
4724 PACKET__RECV, &ad);
4725 if (err)
4726 return err;
4727 }
4728
4729 return err;
4730}
4731
4732static int selinux_socket_getpeersec_stream(struct socket *sock, char __user *optval,
4733 int __user *optlen, unsigned len)
4734{
4735 int err = 0;
4736 char *scontext;
4737 u32 scontext_len;
4738 struct sk_security_struct *sksec = sock->sk->sk_security;
4739 u32 peer_sid = SECSID_NULL;
4740
4741 if (sksec->sclass == SECCLASS_UNIX_STREAM_SOCKET ||
4742 sksec->sclass == SECCLASS_TCP_SOCKET)
4743 peer_sid = sksec->peer_sid;
4744 if (peer_sid == SECSID_NULL)
4745 return -ENOPROTOOPT;
4746
4747 err = security_sid_to_context(peer_sid, &scontext, &scontext_len);
4748 if (err)
4749 return err;
4750
4751 if (scontext_len > len) {
4752 err = -ERANGE;
4753 goto out_len;
4754 }
4755
4756 if (copy_to_user(optval, scontext, scontext_len))
4757 err = -EFAULT;
4758
4759out_len:
4760 if (put_user(scontext_len, optlen))
4761 err = -EFAULT;
4762 kfree(scontext);
4763 return err;
4764}
4765
4766static int selinux_socket_getpeersec_dgram(struct socket *sock, struct sk_buff *skb, u32 *secid)
4767{
4768 u32 peer_secid = SECSID_NULL;
4769 u16 family;
4770 struct inode_security_struct *isec;
4771
4772 if (skb && skb->protocol == htons(ETH_P_IP))
4773 family = PF_INET;
4774 else if (skb && skb->protocol == htons(ETH_P_IPV6))
4775 family = PF_INET6;
4776 else if (sock)
4777 family = sock->sk->sk_family;
4778 else
4779 goto out;
4780
4781 if (sock && family == PF_UNIX) {
4782 isec = inode_security_novalidate(SOCK_INODE(sock));
4783 peer_secid = isec->sid;
4784 } else if (skb)
4785 selinux_skb_peerlbl_sid(skb, family, &peer_secid);
4786
4787out:
4788 *secid = peer_secid;
4789 if (peer_secid == SECSID_NULL)
4790 return -EINVAL;
4791 return 0;
4792}
4793
4794static int selinux_sk_alloc_security(struct sock *sk, int family, gfp_t priority)
4795{
4796 struct sk_security_struct *sksec;
4797
4798 sksec = kzalloc(sizeof(*sksec), priority);
4799 if (!sksec)
4800 return -ENOMEM;
4801
4802 sksec->peer_sid = SECINITSID_UNLABELED;
4803 sksec->sid = SECINITSID_UNLABELED;
4804 sksec->sclass = SECCLASS_SOCKET;
4805 selinux_netlbl_sk_security_reset(sksec);
4806 sk->sk_security = sksec;
4807
4808 return 0;
4809}
4810
4811static void selinux_sk_free_security(struct sock *sk)
4812{
4813 struct sk_security_struct *sksec = sk->sk_security;
4814
4815 sk->sk_security = NULL;
4816 selinux_netlbl_sk_security_free(sksec);
4817 kfree(sksec);
4818}
4819
4820static void selinux_sk_clone_security(const struct sock *sk, struct sock *newsk)
4821{
4822 struct sk_security_struct *sksec = sk->sk_security;
4823 struct sk_security_struct *newsksec = newsk->sk_security;
4824
4825 newsksec->sid = sksec->sid;
4826 newsksec->peer_sid = sksec->peer_sid;
4827 newsksec->sclass = sksec->sclass;
4828
4829 selinux_netlbl_sk_security_reset(newsksec);
4830}
4831
4832static void selinux_sk_getsecid(struct sock *sk, u32 *secid)
4833{
4834 if (!sk)
4835 *secid = SECINITSID_ANY_SOCKET;
4836 else {
4837 struct sk_security_struct *sksec = sk->sk_security;
4838
4839 *secid = sksec->sid;
4840 }
4841}
4842
4843static void selinux_sock_graft(struct sock *sk, struct socket *parent)
4844{
4845 struct inode_security_struct *isec =
4846 inode_security_novalidate(SOCK_INODE(parent));
4847 struct sk_security_struct *sksec = sk->sk_security;
4848
4849 if (sk->sk_family == PF_INET || sk->sk_family == PF_INET6 ||
4850 sk->sk_family == PF_UNIX)
4851 isec->sid = sksec->sid;
4852 sksec->sclass = isec->sclass;
4853}
4854
4855static int selinux_inet_conn_request(struct sock *sk, struct sk_buff *skb,
4856 struct request_sock *req)
4857{
4858 struct sk_security_struct *sksec = sk->sk_security;
4859 int err;
4860 u16 family = req->rsk_ops->family;
4861 u32 connsid;
4862 u32 peersid;
4863
4864 err = selinux_skb_peerlbl_sid(skb, family, &peersid);
4865 if (err)
4866 return err;
4867 err = selinux_conn_sid(sksec->sid, peersid, &connsid);
4868 if (err)
4869 return err;
4870 req->secid = connsid;
4871 req->peer_secid = peersid;
4872
4873 return selinux_netlbl_inet_conn_request(req, family);
4874}
4875
4876static void selinux_inet_csk_clone(struct sock *newsk,
4877 const struct request_sock *req)
4878{
4879 struct sk_security_struct *newsksec = newsk->sk_security;
4880
4881 newsksec->sid = req->secid;
4882 newsksec->peer_sid = req->peer_secid;
4883 /* NOTE: Ideally, we should also get the isec->sid for the
4884 new socket in sync, but we don't have the isec available yet.
4885 So we will wait until sock_graft to do it, by which
4886 time it will have been created and available. */
4887
4888 /* We don't need to take any sort of lock here as we are the only
4889 * thread with access to newsksec */
4890 selinux_netlbl_inet_csk_clone(newsk, req->rsk_ops->family);
4891}
4892
4893static void selinux_inet_conn_established(struct sock *sk, struct sk_buff *skb)
4894{
4895 u16 family = sk->sk_family;
4896 struct sk_security_struct *sksec = sk->sk_security;
4897
4898 /* handle mapped IPv4 packets arriving via IPv6 sockets */
4899 if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
4900 family = PF_INET;
4901
4902 selinux_skb_peerlbl_sid(skb, family, &sksec->peer_sid);
4903}
4904
4905static int selinux_secmark_relabel_packet(u32 sid)
4906{
4907 const struct task_security_struct *__tsec;
4908 u32 tsid;
4909
4910 __tsec = current_security();
4911 tsid = __tsec->sid;
4912
4913 return avc_has_perm(tsid, sid, SECCLASS_PACKET, PACKET__RELABELTO, NULL);
4914}
4915
4916static void selinux_secmark_refcount_inc(void)
4917{
4918 atomic_inc(&selinux_secmark_refcount);
4919}
4920
4921static void selinux_secmark_refcount_dec(void)
4922{
4923 atomic_dec(&selinux_secmark_refcount);
4924}
4925
4926static void selinux_req_classify_flow(const struct request_sock *req,
4927 struct flowi *fl)
4928{
4929 fl->flowi_secid = req->secid;
4930}
4931
4932static int selinux_tun_dev_alloc_security(void **security)
4933{
4934 struct tun_security_struct *tunsec;
4935
4936 tunsec = kzalloc(sizeof(*tunsec), GFP_KERNEL);
4937 if (!tunsec)
4938 return -ENOMEM;
4939 tunsec->sid = current_sid();
4940
4941 *security = tunsec;
4942 return 0;
4943}
4944
4945static void selinux_tun_dev_free_security(void *security)
4946{
4947 kfree(security);
4948}
4949
4950static int selinux_tun_dev_create(void)
4951{
4952 u32 sid = current_sid();
4953
4954 /* we aren't taking into account the "sockcreate" SID since the socket
4955 * that is being created here is not a socket in the traditional sense,
4956 * instead it is a private sock, accessible only to the kernel, and
4957 * representing a wide range of network traffic spanning multiple
4958 * connections unlike traditional sockets - check the TUN driver to
4959 * get a better understanding of why this socket is special */
4960
4961 return avc_has_perm(sid, sid, SECCLASS_TUN_SOCKET, TUN_SOCKET__CREATE,
4962 NULL);
4963}
4964
4965static int selinux_tun_dev_attach_queue(void *security)
4966{
4967 struct tun_security_struct *tunsec = security;
4968
4969 return avc_has_perm(current_sid(), tunsec->sid, SECCLASS_TUN_SOCKET,
4970 TUN_SOCKET__ATTACH_QUEUE, NULL);
4971}
4972
4973static int selinux_tun_dev_attach(struct sock *sk, void *security)
4974{
4975 struct tun_security_struct *tunsec = security;
4976 struct sk_security_struct *sksec = sk->sk_security;
4977
4978 /* we don't currently perform any NetLabel based labeling here and it
4979 * isn't clear that we would want to do so anyway; while we could apply
4980 * labeling without the support of the TUN user the resulting labeled
4981 * traffic from the other end of the connection would almost certainly
4982 * cause confusion to the TUN user that had no idea network labeling
4983 * protocols were being used */
4984
4985 sksec->sid = tunsec->sid;
4986 sksec->sclass = SECCLASS_TUN_SOCKET;
4987
4988 return 0;
4989}
4990
4991static int selinux_tun_dev_open(void *security)
4992{
4993 struct tun_security_struct *tunsec = security;
4994 u32 sid = current_sid();
4995 int err;
4996
4997 err = avc_has_perm(sid, tunsec->sid, SECCLASS_TUN_SOCKET,
4998 TUN_SOCKET__RELABELFROM, NULL);
4999 if (err)
5000 return err;
5001 err = avc_has_perm(sid, sid, SECCLASS_TUN_SOCKET,
5002 TUN_SOCKET__RELABELTO, NULL);
5003 if (err)
5004 return err;
5005 tunsec->sid = sid;
5006
5007 return 0;
5008}
5009
5010static int selinux_nlmsg_perm(struct sock *sk, struct sk_buff *skb)
5011{
5012 int err = 0;
5013 u32 perm;
5014 struct nlmsghdr *nlh;
5015 struct sk_security_struct *sksec = sk->sk_security;
5016
5017 if (skb->len < NLMSG_HDRLEN) {
5018 err = -EINVAL;
5019 goto out;
5020 }
5021 nlh = nlmsg_hdr(skb);
5022
5023 err = selinux_nlmsg_lookup(sksec->sclass, nlh->nlmsg_type, &perm);
5024 if (err) {
5025 if (err == -EINVAL) {
5026 pr_warn_ratelimited("SELinux: unrecognized netlink"
5027 " message: protocol=%hu nlmsg_type=%hu sclass=%s"
5028 " pig=%d comm=%s\n",
5029 sk->sk_protocol, nlh->nlmsg_type,
5030 secclass_map[sksec->sclass - 1].name,
5031 task_pid_nr(current), current->comm);
5032 if (!selinux_enforcing || security_get_allow_unknown())
5033 err = 0;
5034 }
5035
5036 /* Ignore */
5037 if (err == -ENOENT)
5038 err = 0;
5039 goto out;
5040 }
5041
5042 err = sock_has_perm(current, sk, perm);
5043out:
5044 return err;
5045}
5046
5047#ifdef CONFIG_NETFILTER
5048
5049static unsigned int selinux_ip_forward(struct sk_buff *skb,
5050 const struct net_device *indev,
5051 u16 family)
5052{
5053 int err;
5054 char *addrp;
5055 u32 peer_sid;
5056 struct common_audit_data ad;
5057 struct lsm_network_audit net = {0,};
5058 u8 secmark_active;
5059 u8 netlbl_active;
5060 u8 peerlbl_active;
5061
5062 if (!selinux_policycap_netpeer)
5063 return NF_ACCEPT;
5064
5065 secmark_active = selinux_secmark_enabled();
5066 netlbl_active = netlbl_enabled();
5067 peerlbl_active = selinux_peerlbl_enabled();
5068 if (!secmark_active && !peerlbl_active)
5069 return NF_ACCEPT;
5070
5071 if (selinux_skb_peerlbl_sid(skb, family, &peer_sid) != 0)
5072 return NF_DROP;
5073
5074 ad.type = LSM_AUDIT_DATA_NET;
5075 ad.u.net = &net;
5076 ad.u.net->netif = indev->ifindex;
5077 ad.u.net->family = family;
5078 if (selinux_parse_skb(skb, &ad, &addrp, 1, NULL) != 0)
5079 return NF_DROP;
5080
5081 if (peerlbl_active) {
5082 err = selinux_inet_sys_rcv_skb(dev_net(indev), indev->ifindex,
5083 addrp, family, peer_sid, &ad);
5084 if (err) {
5085 selinux_netlbl_err(skb, family, err, 1);
5086 return NF_DROP;
5087 }
5088 }
5089
5090 if (secmark_active)
5091 if (avc_has_perm(peer_sid, skb->secmark,
5092 SECCLASS_PACKET, PACKET__FORWARD_IN, &ad))
5093 return NF_DROP;
5094
5095 if (netlbl_active)
5096 /* we do this in the FORWARD path and not the POST_ROUTING
5097 * path because we want to make sure we apply the necessary
5098 * labeling before IPsec is applied so we can leverage AH
5099 * protection */
5100 if (selinux_netlbl_skbuff_setsid(skb, family, peer_sid) != 0)
5101 return NF_DROP;
5102
5103 return NF_ACCEPT;
5104}
5105
5106static unsigned int selinux_ipv4_forward(void *priv,
5107 struct sk_buff *skb,
5108 const struct nf_hook_state *state)
5109{
5110 return selinux_ip_forward(skb, state->in, PF_INET);
5111}
5112
5113#if IS_ENABLED(CONFIG_IPV6)
5114static unsigned int selinux_ipv6_forward(void *priv,
5115 struct sk_buff *skb,
5116 const struct nf_hook_state *state)
5117{
5118 return selinux_ip_forward(skb, state->in, PF_INET6);
5119}
5120#endif /* IPV6 */
5121
5122static unsigned int selinux_ip_output(struct sk_buff *skb,
5123 u16 family)
5124{
5125 struct sock *sk;
5126 u32 sid;
5127
5128 if (!netlbl_enabled())
5129 return NF_ACCEPT;
5130
5131 /* we do this in the LOCAL_OUT path and not the POST_ROUTING path
5132 * because we want to make sure we apply the necessary labeling
5133 * before IPsec is applied so we can leverage AH protection */
5134 sk = skb->sk;
5135 if (sk) {
5136 struct sk_security_struct *sksec;
5137
5138 if (sk_listener(sk))
5139 /* if the socket is the listening state then this
5140 * packet is a SYN-ACK packet which means it needs to
5141 * be labeled based on the connection/request_sock and
5142 * not the parent socket. unfortunately, we can't
5143 * lookup the request_sock yet as it isn't queued on
5144 * the parent socket until after the SYN-ACK is sent.
5145 * the "solution" is to simply pass the packet as-is
5146 * as any IP option based labeling should be copied
5147 * from the initial connection request (in the IP
5148 * layer). it is far from ideal, but until we get a
5149 * security label in the packet itself this is the
5150 * best we can do. */
5151 return NF_ACCEPT;
5152
5153 /* standard practice, label using the parent socket */
5154 sksec = sk->sk_security;
5155 sid = sksec->sid;
5156 } else
5157 sid = SECINITSID_KERNEL;
5158 if (selinux_netlbl_skbuff_setsid(skb, family, sid) != 0)
5159 return NF_DROP;
5160
5161 return NF_ACCEPT;
5162}
5163
5164static unsigned int selinux_ipv4_output(void *priv,
5165 struct sk_buff *skb,
5166 const struct nf_hook_state *state)
5167{
5168 return selinux_ip_output(skb, PF_INET);
5169}
5170
5171#if IS_ENABLED(CONFIG_IPV6)
5172static unsigned int selinux_ipv6_output(void *priv,
5173 struct sk_buff *skb,
5174 const struct nf_hook_state *state)
5175{
5176 return selinux_ip_output(skb, PF_INET6);
5177}
5178#endif /* IPV6 */
5179
5180static unsigned int selinux_ip_postroute_compat(struct sk_buff *skb,
5181 int ifindex,
5182 u16 family)
5183{
5184 struct sock *sk = skb_to_full_sk(skb);
5185 struct sk_security_struct *sksec;
5186 struct common_audit_data ad;
5187 struct lsm_network_audit net = {0,};
5188 char *addrp;
5189 u8 proto;
5190
5191 if (sk == NULL)
5192 return NF_ACCEPT;
5193 sksec = sk->sk_security;
5194
5195 ad.type = LSM_AUDIT_DATA_NET;
5196 ad.u.net = &net;
5197 ad.u.net->netif = ifindex;
5198 ad.u.net->family = family;
5199 if (selinux_parse_skb(skb, &ad, &addrp, 0, &proto))
5200 return NF_DROP;
5201
5202 if (selinux_secmark_enabled())
5203 if (avc_has_perm(sksec->sid, skb->secmark,
5204 SECCLASS_PACKET, PACKET__SEND, &ad))
5205 return NF_DROP_ERR(-ECONNREFUSED);
5206
5207 if (selinux_xfrm_postroute_last(sksec->sid, skb, &ad, proto))
5208 return NF_DROP_ERR(-ECONNREFUSED);
5209
5210 return NF_ACCEPT;
5211}
5212
5213static unsigned int selinux_ip_postroute(struct sk_buff *skb,
5214 const struct net_device *outdev,
5215 u16 family)
5216{
5217 u32 secmark_perm;
5218 u32 peer_sid;
5219 int ifindex = outdev->ifindex;
5220 struct sock *sk;
5221 struct common_audit_data ad;
5222 struct lsm_network_audit net = {0,};
5223 char *addrp;
5224 u8 secmark_active;
5225 u8 peerlbl_active;
5226
5227 /* If any sort of compatibility mode is enabled then handoff processing
5228 * to the selinux_ip_postroute_compat() function to deal with the
5229 * special handling. We do this in an attempt to keep this function
5230 * as fast and as clean as possible. */
5231 if (!selinux_policycap_netpeer)
5232 return selinux_ip_postroute_compat(skb, ifindex, family);
5233
5234 secmark_active = selinux_secmark_enabled();
5235 peerlbl_active = selinux_peerlbl_enabled();
5236 if (!secmark_active && !peerlbl_active)
5237 return NF_ACCEPT;
5238
5239 sk = skb_to_full_sk(skb);
5240
5241#ifdef CONFIG_XFRM
5242 /* If skb->dst->xfrm is non-NULL then the packet is undergoing an IPsec
5243 * packet transformation so allow the packet to pass without any checks
5244 * since we'll have another chance to perform access control checks
5245 * when the packet is on it's final way out.
5246 * NOTE: there appear to be some IPv6 multicast cases where skb->dst
5247 * is NULL, in this case go ahead and apply access control.
5248 * NOTE: if this is a local socket (skb->sk != NULL) that is in the
5249 * TCP listening state we cannot wait until the XFRM processing
5250 * is done as we will miss out on the SA label if we do;
5251 * unfortunately, this means more work, but it is only once per
5252 * connection. */
5253 if (skb_dst(skb) != NULL && skb_dst(skb)->xfrm != NULL &&
5254 !(sk && sk_listener(sk)))
5255 return NF_ACCEPT;
5256#endif
5257
5258 if (sk == NULL) {
5259 /* Without an associated socket the packet is either coming
5260 * from the kernel or it is being forwarded; check the packet
5261 * to determine which and if the packet is being forwarded
5262 * query the packet directly to determine the security label. */
5263 if (skb->skb_iif) {
5264 secmark_perm = PACKET__FORWARD_OUT;
5265 if (selinux_skb_peerlbl_sid(skb, family, &peer_sid))
5266 return NF_DROP;
5267 } else {
5268 secmark_perm = PACKET__SEND;
5269 peer_sid = SECINITSID_KERNEL;
5270 }
5271 } else if (sk_listener(sk)) {
5272 /* Locally generated packet but the associated socket is in the
5273 * listening state which means this is a SYN-ACK packet. In
5274 * this particular case the correct security label is assigned
5275 * to the connection/request_sock but unfortunately we can't
5276 * query the request_sock as it isn't queued on the parent
5277 * socket until after the SYN-ACK packet is sent; the only
5278 * viable choice is to regenerate the label like we do in
5279 * selinux_inet_conn_request(). See also selinux_ip_output()
5280 * for similar problems. */
5281 u32 skb_sid;
5282 struct sk_security_struct *sksec;
5283
5284 sksec = sk->sk_security;
5285 if (selinux_skb_peerlbl_sid(skb, family, &skb_sid))
5286 return NF_DROP;
5287 /* At this point, if the returned skb peerlbl is SECSID_NULL
5288 * and the packet has been through at least one XFRM
5289 * transformation then we must be dealing with the "final"
5290 * form of labeled IPsec packet; since we've already applied
5291 * all of our access controls on this packet we can safely
5292 * pass the packet. */
5293 if (skb_sid == SECSID_NULL) {
5294 switch (family) {
5295 case PF_INET:
5296 if (IPCB(skb)->flags & IPSKB_XFRM_TRANSFORMED)
5297 return NF_ACCEPT;
5298 break;
5299 case PF_INET6:
5300 if (IP6CB(skb)->flags & IP6SKB_XFRM_TRANSFORMED)
5301 return NF_ACCEPT;
5302 break;
5303 default:
5304 return NF_DROP_ERR(-ECONNREFUSED);
5305 }
5306 }
5307 if (selinux_conn_sid(sksec->sid, skb_sid, &peer_sid))
5308 return NF_DROP;
5309 secmark_perm = PACKET__SEND;
5310 } else {
5311 /* Locally generated packet, fetch the security label from the
5312 * associated socket. */
5313 struct sk_security_struct *sksec = sk->sk_security;
5314 peer_sid = sksec->sid;
5315 secmark_perm = PACKET__SEND;
5316 }
5317
5318 ad.type = LSM_AUDIT_DATA_NET;
5319 ad.u.net = &net;
5320 ad.u.net->netif = ifindex;
5321 ad.u.net->family = family;
5322 if (selinux_parse_skb(skb, &ad, &addrp, 0, NULL))
5323 return NF_DROP;
5324
5325 if (secmark_active)
5326 if (avc_has_perm(peer_sid, skb->secmark,
5327 SECCLASS_PACKET, secmark_perm, &ad))
5328 return NF_DROP_ERR(-ECONNREFUSED);
5329
5330 if (peerlbl_active) {
5331 u32 if_sid;
5332 u32 node_sid;
5333
5334 if (sel_netif_sid(dev_net(outdev), ifindex, &if_sid))
5335 return NF_DROP;
5336 if (avc_has_perm(peer_sid, if_sid,
5337 SECCLASS_NETIF, NETIF__EGRESS, &ad))
5338 return NF_DROP_ERR(-ECONNREFUSED);
5339
5340 if (sel_netnode_sid(addrp, family, &node_sid))
5341 return NF_DROP;
5342 if (avc_has_perm(peer_sid, node_sid,
5343 SECCLASS_NODE, NODE__SENDTO, &ad))
5344 return NF_DROP_ERR(-ECONNREFUSED);
5345 }
5346
5347 return NF_ACCEPT;
5348}
5349
5350static unsigned int selinux_ipv4_postroute(void *priv,
5351 struct sk_buff *skb,
5352 const struct nf_hook_state *state)
5353{
5354 return selinux_ip_postroute(skb, state->out, PF_INET);
5355}
5356
5357#if IS_ENABLED(CONFIG_IPV6)
5358static unsigned int selinux_ipv6_postroute(void *priv,
5359 struct sk_buff *skb,
5360 const struct nf_hook_state *state)
5361{
5362 return selinux_ip_postroute(skb, state->out, PF_INET6);
5363}
5364#endif /* IPV6 */
5365
5366#endif /* CONFIG_NETFILTER */
5367
5368static int selinux_netlink_send(struct sock *sk, struct sk_buff *skb)
5369{
5370 return selinux_nlmsg_perm(sk, skb);
5371}
5372
5373static int ipc_alloc_security(struct task_struct *task,
5374 struct kern_ipc_perm *perm,
5375 u16 sclass)
5376{
5377 struct ipc_security_struct *isec;
5378 u32 sid;
5379
5380 isec = kzalloc(sizeof(struct ipc_security_struct), GFP_KERNEL);
5381 if (!isec)
5382 return -ENOMEM;
5383
5384 sid = task_sid(task);
5385 isec->sclass = sclass;
5386 isec->sid = sid;
5387 perm->security = isec;
5388
5389 return 0;
5390}
5391
5392static void ipc_free_security(struct kern_ipc_perm *perm)
5393{
5394 struct ipc_security_struct *isec = perm->security;
5395 perm->security = NULL;
5396 kfree(isec);
5397}
5398
5399static int msg_msg_alloc_security(struct msg_msg *msg)
5400{
5401 struct msg_security_struct *msec;
5402
5403 msec = kzalloc(sizeof(struct msg_security_struct), GFP_KERNEL);
5404 if (!msec)
5405 return -ENOMEM;
5406
5407 msec->sid = SECINITSID_UNLABELED;
5408 msg->security = msec;
5409
5410 return 0;
5411}
5412
5413static void msg_msg_free_security(struct msg_msg *msg)
5414{
5415 struct msg_security_struct *msec = msg->security;
5416
5417 msg->security = NULL;
5418 kfree(msec);
5419}
5420
5421static int ipc_has_perm(struct kern_ipc_perm *ipc_perms,
5422 u32 perms)
5423{
5424 struct ipc_security_struct *isec;
5425 struct common_audit_data ad;
5426 u32 sid = current_sid();
5427
5428 isec = ipc_perms->security;
5429
5430 ad.type = LSM_AUDIT_DATA_IPC;
5431 ad.u.ipc_id = ipc_perms->key;
5432
5433 return avc_has_perm(sid, isec->sid, isec->sclass, perms, &ad);
5434}
5435
5436static int selinux_msg_msg_alloc_security(struct msg_msg *msg)
5437{
5438 return msg_msg_alloc_security(msg);
5439}
5440
5441static void selinux_msg_msg_free_security(struct msg_msg *msg)
5442{
5443 msg_msg_free_security(msg);
5444}
5445
5446/* message queue security operations */
5447static int selinux_msg_queue_alloc_security(struct msg_queue *msq)
5448{
5449 struct ipc_security_struct *isec;
5450 struct common_audit_data ad;
5451 u32 sid = current_sid();
5452 int rc;
5453
5454 rc = ipc_alloc_security(current, &msq->q_perm, SECCLASS_MSGQ);
5455 if (rc)
5456 return rc;
5457
5458 isec = msq->q_perm.security;
5459
5460 ad.type = LSM_AUDIT_DATA_IPC;
5461 ad.u.ipc_id = msq->q_perm.key;
5462
5463 rc = avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
5464 MSGQ__CREATE, &ad);
5465 if (rc) {
5466 ipc_free_security(&msq->q_perm);
5467 return rc;
5468 }
5469 return 0;
5470}
5471
5472static void selinux_msg_queue_free_security(struct msg_queue *msq)
5473{
5474 ipc_free_security(&msq->q_perm);
5475}
5476
5477static int selinux_msg_queue_associate(struct msg_queue *msq, int msqflg)
5478{
5479 struct ipc_security_struct *isec;
5480 struct common_audit_data ad;
5481 u32 sid = current_sid();
5482
5483 isec = msq->q_perm.security;
5484
5485 ad.type = LSM_AUDIT_DATA_IPC;
5486 ad.u.ipc_id = msq->q_perm.key;
5487
5488 return avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
5489 MSGQ__ASSOCIATE, &ad);
5490}
5491
5492static int selinux_msg_queue_msgctl(struct msg_queue *msq, int cmd)
5493{
5494 int err;
5495 int perms;
5496
5497 switch (cmd) {
5498 case IPC_INFO:
5499 case MSG_INFO:
5500 /* No specific object, just general system-wide information. */
5501 return task_has_system(current, SYSTEM__IPC_INFO);
5502 case IPC_STAT:
5503 case MSG_STAT:
5504 perms = MSGQ__GETATTR | MSGQ__ASSOCIATE;
5505 break;
5506 case IPC_SET:
5507 perms = MSGQ__SETATTR;
5508 break;
5509 case IPC_RMID:
5510 perms = MSGQ__DESTROY;
5511 break;
5512 default:
5513 return 0;
5514 }
5515
5516 err = ipc_has_perm(&msq->q_perm, perms);
5517 return err;
5518}
5519
5520static int selinux_msg_queue_msgsnd(struct msg_queue *msq, struct msg_msg *msg, int msqflg)
5521{
5522 struct ipc_security_struct *isec;
5523 struct msg_security_struct *msec;
5524 struct common_audit_data ad;
5525 u32 sid = current_sid();
5526 int rc;
5527
5528 isec = msq->q_perm.security;
5529 msec = msg->security;
5530
5531 /*
5532 * First time through, need to assign label to the message
5533 */
5534 if (msec->sid == SECINITSID_UNLABELED) {
5535 /*
5536 * Compute new sid based on current process and
5537 * message queue this message will be stored in
5538 */
5539 rc = security_transition_sid(sid, isec->sid, SECCLASS_MSG,
5540 NULL, &msec->sid);
5541 if (rc)
5542 return rc;
5543 }
5544
5545 ad.type = LSM_AUDIT_DATA_IPC;
5546 ad.u.ipc_id = msq->q_perm.key;
5547
5548 /* Can this process write to the queue? */
5549 rc = avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
5550 MSGQ__WRITE, &ad);
5551 if (!rc)
5552 /* Can this process send the message */
5553 rc = avc_has_perm(sid, msec->sid, SECCLASS_MSG,
5554 MSG__SEND, &ad);
5555 if (!rc)
5556 /* Can the message be put in the queue? */
5557 rc = avc_has_perm(msec->sid, isec->sid, SECCLASS_MSGQ,
5558 MSGQ__ENQUEUE, &ad);
5559
5560 return rc;
5561}
5562
5563static int selinux_msg_queue_msgrcv(struct msg_queue *msq, struct msg_msg *msg,
5564 struct task_struct *target,
5565 long type, int mode)
5566{
5567 struct ipc_security_struct *isec;
5568 struct msg_security_struct *msec;
5569 struct common_audit_data ad;
5570 u32 sid = task_sid(target);
5571 int rc;
5572
5573 isec = msq->q_perm.security;
5574 msec = msg->security;
5575
5576 ad.type = LSM_AUDIT_DATA_IPC;
5577 ad.u.ipc_id = msq->q_perm.key;
5578
5579 rc = avc_has_perm(sid, isec->sid,
5580 SECCLASS_MSGQ, MSGQ__READ, &ad);
5581 if (!rc)
5582 rc = avc_has_perm(sid, msec->sid,
5583 SECCLASS_MSG, MSG__RECEIVE, &ad);
5584 return rc;
5585}
5586
5587/* Shared Memory security operations */
5588static int selinux_shm_alloc_security(struct shmid_kernel *shp)
5589{
5590 struct ipc_security_struct *isec;
5591 struct common_audit_data ad;
5592 u32 sid = current_sid();
5593 int rc;
5594
5595 rc = ipc_alloc_security(current, &shp->shm_perm, SECCLASS_SHM);
5596 if (rc)
5597 return rc;
5598
5599 isec = shp->shm_perm.security;
5600
5601 ad.type = LSM_AUDIT_DATA_IPC;
5602 ad.u.ipc_id = shp->shm_perm.key;
5603
5604 rc = avc_has_perm(sid, isec->sid, SECCLASS_SHM,
5605 SHM__CREATE, &ad);
5606 if (rc) {
5607 ipc_free_security(&shp->shm_perm);
5608 return rc;
5609 }
5610 return 0;
5611}
5612
5613static void selinux_shm_free_security(struct shmid_kernel *shp)
5614{
5615 ipc_free_security(&shp->shm_perm);
5616}
5617
5618static int selinux_shm_associate(struct shmid_kernel *shp, int shmflg)
5619{
5620 struct ipc_security_struct *isec;
5621 struct common_audit_data ad;
5622 u32 sid = current_sid();
5623
5624 isec = shp->shm_perm.security;
5625
5626 ad.type = LSM_AUDIT_DATA_IPC;
5627 ad.u.ipc_id = shp->shm_perm.key;
5628
5629 return avc_has_perm(sid, isec->sid, SECCLASS_SHM,
5630 SHM__ASSOCIATE, &ad);
5631}
5632
5633/* Note, at this point, shp is locked down */
5634static int selinux_shm_shmctl(struct shmid_kernel *shp, int cmd)
5635{
5636 int perms;
5637 int err;
5638
5639 switch (cmd) {
5640 case IPC_INFO:
5641 case SHM_INFO:
5642 /* No specific object, just general system-wide information. */
5643 return task_has_system(current, SYSTEM__IPC_INFO);
5644 case IPC_STAT:
5645 case SHM_STAT:
5646 perms = SHM__GETATTR | SHM__ASSOCIATE;
5647 break;
5648 case IPC_SET:
5649 perms = SHM__SETATTR;
5650 break;
5651 case SHM_LOCK:
5652 case SHM_UNLOCK:
5653 perms = SHM__LOCK;
5654 break;
5655 case IPC_RMID:
5656 perms = SHM__DESTROY;
5657 break;
5658 default:
5659 return 0;
5660 }
5661
5662 err = ipc_has_perm(&shp->shm_perm, perms);
5663 return err;
5664}
5665
5666static int selinux_shm_shmat(struct shmid_kernel *shp,
5667 char __user *shmaddr, int shmflg)
5668{
5669 u32 perms;
5670
5671 if (shmflg & SHM_RDONLY)
5672 perms = SHM__READ;
5673 else
5674 perms = SHM__READ | SHM__WRITE;
5675
5676 return ipc_has_perm(&shp->shm_perm, perms);
5677}
5678
5679/* Semaphore security operations */
5680static int selinux_sem_alloc_security(struct sem_array *sma)
5681{
5682 struct ipc_security_struct *isec;
5683 struct common_audit_data ad;
5684 u32 sid = current_sid();
5685 int rc;
5686
5687 rc = ipc_alloc_security(current, &sma->sem_perm, SECCLASS_SEM);
5688 if (rc)
5689 return rc;
5690
5691 isec = sma->sem_perm.security;
5692
5693 ad.type = LSM_AUDIT_DATA_IPC;
5694 ad.u.ipc_id = sma->sem_perm.key;
5695
5696 rc = avc_has_perm(sid, isec->sid, SECCLASS_SEM,
5697 SEM__CREATE, &ad);
5698 if (rc) {
5699 ipc_free_security(&sma->sem_perm);
5700 return rc;
5701 }
5702 return 0;
5703}
5704
5705static void selinux_sem_free_security(struct sem_array *sma)
5706{
5707 ipc_free_security(&sma->sem_perm);
5708}
5709
5710static int selinux_sem_associate(struct sem_array *sma, int semflg)
5711{
5712 struct ipc_security_struct *isec;
5713 struct common_audit_data ad;
5714 u32 sid = current_sid();
5715
5716 isec = sma->sem_perm.security;
5717
5718 ad.type = LSM_AUDIT_DATA_IPC;
5719 ad.u.ipc_id = sma->sem_perm.key;
5720
5721 return avc_has_perm(sid, isec->sid, SECCLASS_SEM,
5722 SEM__ASSOCIATE, &ad);
5723}
5724
5725/* Note, at this point, sma is locked down */
5726static int selinux_sem_semctl(struct sem_array *sma, int cmd)
5727{
5728 int err;
5729 u32 perms;
5730
5731 switch (cmd) {
5732 case IPC_INFO:
5733 case SEM_INFO:
5734 /* No specific object, just general system-wide information. */
5735 return task_has_system(current, SYSTEM__IPC_INFO);
5736 case GETPID:
5737 case GETNCNT:
5738 case GETZCNT:
5739 perms = SEM__GETATTR;
5740 break;
5741 case GETVAL:
5742 case GETALL:
5743 perms = SEM__READ;
5744 break;
5745 case SETVAL:
5746 case SETALL:
5747 perms = SEM__WRITE;
5748 break;
5749 case IPC_RMID:
5750 perms = SEM__DESTROY;
5751 break;
5752 case IPC_SET:
5753 perms = SEM__SETATTR;
5754 break;
5755 case IPC_STAT:
5756 case SEM_STAT:
5757 perms = SEM__GETATTR | SEM__ASSOCIATE;
5758 break;
5759 default:
5760 return 0;
5761 }
5762
5763 err = ipc_has_perm(&sma->sem_perm, perms);
5764 return err;
5765}
5766
5767static int selinux_sem_semop(struct sem_array *sma,
5768 struct sembuf *sops, unsigned nsops, int alter)
5769{
5770 u32 perms;
5771
5772 if (alter)
5773 perms = SEM__READ | SEM__WRITE;
5774 else
5775 perms = SEM__READ;
5776
5777 return ipc_has_perm(&sma->sem_perm, perms);
5778}
5779
5780static int selinux_ipc_permission(struct kern_ipc_perm *ipcp, short flag)
5781{
5782 u32 av = 0;
5783
5784 av = 0;
5785 if (flag & S_IRUGO)
5786 av |= IPC__UNIX_READ;
5787 if (flag & S_IWUGO)
5788 av |= IPC__UNIX_WRITE;
5789
5790 if (av == 0)
5791 return 0;
5792
5793 return ipc_has_perm(ipcp, av);
5794}
5795
5796static void selinux_ipc_getsecid(struct kern_ipc_perm *ipcp, u32 *secid)
5797{
5798 struct ipc_security_struct *isec = ipcp->security;
5799 *secid = isec->sid;
5800}
5801
5802static void selinux_d_instantiate(struct dentry *dentry, struct inode *inode)
5803{
5804 if (inode)
5805 inode_doinit_with_dentry(inode, dentry);
5806}
5807
5808static int selinux_getprocattr(struct task_struct *p,
5809 char *name, char **value)
5810{
5811 const struct task_security_struct *__tsec;
5812 u32 sid;
5813 int error;
5814 unsigned len;
5815
5816 if (current != p) {
5817 error = current_has_perm(p, PROCESS__GETATTR);
5818 if (error)
5819 return error;
5820 }
5821
5822 rcu_read_lock();
5823 __tsec = __task_cred(p)->security;
5824
5825 if (!strcmp(name, "current"))
5826 sid = __tsec->sid;
5827 else if (!strcmp(name, "prev"))
5828 sid = __tsec->osid;
5829 else if (!strcmp(name, "exec"))
5830 sid = __tsec->exec_sid;
5831 else if (!strcmp(name, "fscreate"))
5832 sid = __tsec->create_sid;
5833 else if (!strcmp(name, "keycreate"))
5834 sid = __tsec->keycreate_sid;
5835 else if (!strcmp(name, "sockcreate"))
5836 sid = __tsec->sockcreate_sid;
5837 else
5838 goto invalid;
5839 rcu_read_unlock();
5840
5841 if (!sid)
5842 return 0;
5843
5844 error = security_sid_to_context(sid, value, &len);
5845 if (error)
5846 return error;
5847 return len;
5848
5849invalid:
5850 rcu_read_unlock();
5851 return -EINVAL;
5852}
5853
5854static int selinux_setprocattr(struct task_struct *p,
5855 char *name, void *value, size_t size)
5856{
5857 struct task_security_struct *tsec;
5858 struct cred *new;
5859 u32 sid = 0, ptsid;
5860 int error;
5861 char *str = value;
5862
5863 if (current != p) {
5864 /* SELinux only allows a process to change its own
5865 security attributes. */
5866 return -EACCES;
5867 }
5868
5869 /*
5870 * Basic control over ability to set these attributes at all.
5871 * current == p, but we'll pass them separately in case the
5872 * above restriction is ever removed.
5873 */
5874 if (!strcmp(name, "exec"))
5875 error = current_has_perm(p, PROCESS__SETEXEC);
5876 else if (!strcmp(name, "fscreate"))
5877 error = current_has_perm(p, PROCESS__SETFSCREATE);
5878 else if (!strcmp(name, "keycreate"))
5879 error = current_has_perm(p, PROCESS__SETKEYCREATE);
5880 else if (!strcmp(name, "sockcreate"))
5881 error = current_has_perm(p, PROCESS__SETSOCKCREATE);
5882 else if (!strcmp(name, "current"))
5883 error = current_has_perm(p, PROCESS__SETCURRENT);
5884 else
5885 error = -EINVAL;
5886 if (error)
5887 return error;
5888
5889 /* Obtain a SID for the context, if one was specified. */
5890 if (size && str[0] && str[0] != '\n') {
5891 if (str[size-1] == '\n') {
5892 str[size-1] = 0;
5893 size--;
5894 }
5895 error = security_context_to_sid(value, size, &sid, GFP_KERNEL);
5896 if (error == -EINVAL && !strcmp(name, "fscreate")) {
5897 if (!capable(CAP_MAC_ADMIN)) {
5898 struct audit_buffer *ab;
5899 size_t audit_size;
5900
5901 /* We strip a nul only if it is at the end, otherwise the
5902 * context contains a nul and we should audit that */
5903 if (str[size - 1] == '\0')
5904 audit_size = size - 1;
5905 else
5906 audit_size = size;
5907 ab = audit_log_start(current->audit_context, GFP_ATOMIC, AUDIT_SELINUX_ERR);
5908 audit_log_format(ab, "op=fscreate invalid_context=");
5909 audit_log_n_untrustedstring(ab, value, audit_size);
5910 audit_log_end(ab);
5911
5912 return error;
5913 }
5914 error = security_context_to_sid_force(value, size,
5915 &sid);
5916 }
5917 if (error)
5918 return error;
5919 }
5920
5921 new = prepare_creds();
5922 if (!new)
5923 return -ENOMEM;
5924
5925 /* Permission checking based on the specified context is
5926 performed during the actual operation (execve,
5927 open/mkdir/...), when we know the full context of the
5928 operation. See selinux_bprm_set_creds for the execve
5929 checks and may_create for the file creation checks. The
5930 operation will then fail if the context is not permitted. */
5931 tsec = new->security;
5932 if (!strcmp(name, "exec")) {
5933 tsec->exec_sid = sid;
5934 } else if (!strcmp(name, "fscreate")) {
5935 tsec->create_sid = sid;
5936 } else if (!strcmp(name, "keycreate")) {
5937 error = may_create_key(sid, p);
5938 if (error)
5939 goto abort_change;
5940 tsec->keycreate_sid = sid;
5941 } else if (!strcmp(name, "sockcreate")) {
5942 tsec->sockcreate_sid = sid;
5943 } else if (!strcmp(name, "current")) {
5944 error = -EINVAL;
5945 if (sid == 0)
5946 goto abort_change;
5947
5948 /* Only allow single threaded processes to change context */
5949 error = -EPERM;
5950 if (!current_is_single_threaded()) {
5951 error = security_bounded_transition(tsec->sid, sid);
5952 if (error)
5953 goto abort_change;
5954 }
5955
5956 /* Check permissions for the transition. */
5957 error = avc_has_perm(tsec->sid, sid, SECCLASS_PROCESS,
5958 PROCESS__DYNTRANSITION, NULL);
5959 if (error)
5960 goto abort_change;
5961
5962 /* Check for ptracing, and update the task SID if ok.
5963 Otherwise, leave SID unchanged and fail. */
5964 ptsid = ptrace_parent_sid(p);
5965 if (ptsid != 0) {
5966 error = avc_has_perm(ptsid, sid, SECCLASS_PROCESS,
5967 PROCESS__PTRACE, NULL);
5968 if (error)
5969 goto abort_change;
5970 }
5971
5972 tsec->sid = sid;
5973 } else {
5974 error = -EINVAL;
5975 goto abort_change;
5976 }
5977
5978 commit_creds(new);
5979 return size;
5980
5981abort_change:
5982 abort_creds(new);
5983 return error;
5984}
5985
5986static int selinux_ismaclabel(const char *name)
5987{
5988 return (strcmp(name, XATTR_SELINUX_SUFFIX) == 0);
5989}
5990
5991static int selinux_secid_to_secctx(u32 secid, char **secdata, u32 *seclen)
5992{
5993 return security_sid_to_context(secid, secdata, seclen);
5994}
5995
5996static int selinux_secctx_to_secid(const char *secdata, u32 seclen, u32 *secid)
5997{
5998 return security_context_to_sid(secdata, seclen, secid, GFP_KERNEL);
5999}
6000
6001static void selinux_release_secctx(char *secdata, u32 seclen)
6002{
6003 kfree(secdata);
6004}
6005
6006static void selinux_inode_invalidate_secctx(struct inode *inode)
6007{
6008 struct inode_security_struct *isec = inode->i_security;
6009
6010 spin_lock(&isec->lock);
6011 isec->initialized = LABEL_INVALID;
6012 spin_unlock(&isec->lock);
6013}
6014
6015/*
6016 * called with inode->i_mutex locked
6017 */
6018static int selinux_inode_notifysecctx(struct inode *inode, void *ctx, u32 ctxlen)
6019{
6020 return selinux_inode_setsecurity(inode, XATTR_SELINUX_SUFFIX, ctx, ctxlen, 0);
6021}
6022
6023/*
6024 * called with inode->i_mutex locked
6025 */
6026static int selinux_inode_setsecctx(struct dentry *dentry, void *ctx, u32 ctxlen)
6027{
6028 return __vfs_setxattr_noperm(dentry, XATTR_NAME_SELINUX, ctx, ctxlen, 0);
6029}
6030
6031static int selinux_inode_getsecctx(struct inode *inode, void **ctx, u32 *ctxlen)
6032{
6033 int len = 0;
6034 len = selinux_inode_getsecurity(inode, XATTR_SELINUX_SUFFIX,
6035 ctx, true);
6036 if (len < 0)
6037 return len;
6038 *ctxlen = len;
6039 return 0;
6040}
6041#ifdef CONFIG_KEYS
6042
6043static int selinux_key_alloc(struct key *k, const struct cred *cred,
6044 unsigned long flags)
6045{
6046 const struct task_security_struct *tsec;
6047 struct key_security_struct *ksec;
6048
6049 ksec = kzalloc(sizeof(struct key_security_struct), GFP_KERNEL);
6050 if (!ksec)
6051 return -ENOMEM;
6052
6053 tsec = cred->security;
6054 if (tsec->keycreate_sid)
6055 ksec->sid = tsec->keycreate_sid;
6056 else
6057 ksec->sid = tsec->sid;
6058
6059 k->security = ksec;
6060 return 0;
6061}
6062
6063static void selinux_key_free(struct key *k)
6064{
6065 struct key_security_struct *ksec = k->security;
6066
6067 k->security = NULL;
6068 kfree(ksec);
6069}
6070
6071static int selinux_key_permission(key_ref_t key_ref,
6072 const struct cred *cred,
6073 unsigned perm)
6074{
6075 struct key *key;
6076 struct key_security_struct *ksec;
6077 u32 sid;
6078
6079 /* if no specific permissions are requested, we skip the
6080 permission check. No serious, additional covert channels
6081 appear to be created. */
6082 if (perm == 0)
6083 return 0;
6084
6085 sid = cred_sid(cred);
6086
6087 key = key_ref_to_ptr(key_ref);
6088 ksec = key->security;
6089
6090 return avc_has_perm(sid, ksec->sid, SECCLASS_KEY, perm, NULL);
6091}
6092
6093static int selinux_key_getsecurity(struct key *key, char **_buffer)
6094{
6095 struct key_security_struct *ksec = key->security;
6096 char *context = NULL;
6097 unsigned len;
6098 int rc;
6099
6100 rc = security_sid_to_context(ksec->sid, &context, &len);
6101 if (!rc)
6102 rc = len;
6103 *_buffer = context;
6104 return rc;
6105}
6106
6107#endif
6108
6109static struct security_hook_list selinux_hooks[] = {
6110 LSM_HOOK_INIT(binder_set_context_mgr, selinux_binder_set_context_mgr),
6111 LSM_HOOK_INIT(binder_transaction, selinux_binder_transaction),
6112 LSM_HOOK_INIT(binder_transfer_binder, selinux_binder_transfer_binder),
6113 LSM_HOOK_INIT(binder_transfer_file, selinux_binder_transfer_file),
6114
6115 LSM_HOOK_INIT(ptrace_access_check, selinux_ptrace_access_check),
6116 LSM_HOOK_INIT(ptrace_traceme, selinux_ptrace_traceme),
6117 LSM_HOOK_INIT(capget, selinux_capget),
6118 LSM_HOOK_INIT(capset, selinux_capset),
6119 LSM_HOOK_INIT(capable, selinux_capable),
6120 LSM_HOOK_INIT(quotactl, selinux_quotactl),
6121 LSM_HOOK_INIT(quota_on, selinux_quota_on),
6122 LSM_HOOK_INIT(syslog, selinux_syslog),
6123 LSM_HOOK_INIT(vm_enough_memory, selinux_vm_enough_memory),
6124
6125 LSM_HOOK_INIT(netlink_send, selinux_netlink_send),
6126
6127 LSM_HOOK_INIT(bprm_set_creds, selinux_bprm_set_creds),
6128 LSM_HOOK_INIT(bprm_committing_creds, selinux_bprm_committing_creds),
6129 LSM_HOOK_INIT(bprm_committed_creds, selinux_bprm_committed_creds),
6130 LSM_HOOK_INIT(bprm_secureexec, selinux_bprm_secureexec),
6131
6132 LSM_HOOK_INIT(sb_alloc_security, selinux_sb_alloc_security),
6133 LSM_HOOK_INIT(sb_free_security, selinux_sb_free_security),
6134 LSM_HOOK_INIT(sb_copy_data, selinux_sb_copy_data),
6135 LSM_HOOK_INIT(sb_remount, selinux_sb_remount),
6136 LSM_HOOK_INIT(sb_kern_mount, selinux_sb_kern_mount),
6137 LSM_HOOK_INIT(sb_show_options, selinux_sb_show_options),
6138 LSM_HOOK_INIT(sb_statfs, selinux_sb_statfs),
6139 LSM_HOOK_INIT(sb_mount, selinux_mount),
6140 LSM_HOOK_INIT(sb_umount, selinux_umount),
6141 LSM_HOOK_INIT(sb_set_mnt_opts, selinux_set_mnt_opts),
6142 LSM_HOOK_INIT(sb_clone_mnt_opts, selinux_sb_clone_mnt_opts),
6143 LSM_HOOK_INIT(sb_parse_opts_str, selinux_parse_opts_str),
6144
6145 LSM_HOOK_INIT(dentry_init_security, selinux_dentry_init_security),
6146 LSM_HOOK_INIT(dentry_create_files_as, selinux_dentry_create_files_as),
6147
6148 LSM_HOOK_INIT(inode_alloc_security, selinux_inode_alloc_security),
6149 LSM_HOOK_INIT(inode_free_security, selinux_inode_free_security),
6150 LSM_HOOK_INIT(inode_init_security, selinux_inode_init_security),
6151 LSM_HOOK_INIT(inode_create, selinux_inode_create),
6152 LSM_HOOK_INIT(inode_link, selinux_inode_link),
6153 LSM_HOOK_INIT(inode_unlink, selinux_inode_unlink),
6154 LSM_HOOK_INIT(inode_symlink, selinux_inode_symlink),
6155 LSM_HOOK_INIT(inode_mkdir, selinux_inode_mkdir),
6156 LSM_HOOK_INIT(inode_rmdir, selinux_inode_rmdir),
6157 LSM_HOOK_INIT(inode_mknod, selinux_inode_mknod),
6158 LSM_HOOK_INIT(inode_rename, selinux_inode_rename),
6159 LSM_HOOK_INIT(inode_readlink, selinux_inode_readlink),
6160 LSM_HOOK_INIT(inode_follow_link, selinux_inode_follow_link),
6161 LSM_HOOK_INIT(inode_permission, selinux_inode_permission),
6162 LSM_HOOK_INIT(inode_setattr, selinux_inode_setattr),
6163 LSM_HOOK_INIT(inode_getattr, selinux_inode_getattr),
6164 LSM_HOOK_INIT(inode_setxattr, selinux_inode_setxattr),
6165 LSM_HOOK_INIT(inode_post_setxattr, selinux_inode_post_setxattr),
6166 LSM_HOOK_INIT(inode_getxattr, selinux_inode_getxattr),
6167 LSM_HOOK_INIT(inode_listxattr, selinux_inode_listxattr),
6168 LSM_HOOK_INIT(inode_removexattr, selinux_inode_removexattr),
6169 LSM_HOOK_INIT(inode_getsecurity, selinux_inode_getsecurity),
6170 LSM_HOOK_INIT(inode_setsecurity, selinux_inode_setsecurity),
6171 LSM_HOOK_INIT(inode_listsecurity, selinux_inode_listsecurity),
6172 LSM_HOOK_INIT(inode_getsecid, selinux_inode_getsecid),
6173 LSM_HOOK_INIT(inode_copy_up, selinux_inode_copy_up),
6174 LSM_HOOK_INIT(inode_copy_up_xattr, selinux_inode_copy_up_xattr),
6175
6176 LSM_HOOK_INIT(file_permission, selinux_file_permission),
6177 LSM_HOOK_INIT(file_alloc_security, selinux_file_alloc_security),
6178 LSM_HOOK_INIT(file_free_security, selinux_file_free_security),
6179 LSM_HOOK_INIT(file_ioctl, selinux_file_ioctl),
6180 LSM_HOOK_INIT(mmap_file, selinux_mmap_file),
6181 LSM_HOOK_INIT(mmap_addr, selinux_mmap_addr),
6182 LSM_HOOK_INIT(file_mprotect, selinux_file_mprotect),
6183 LSM_HOOK_INIT(file_lock, selinux_file_lock),
6184 LSM_HOOK_INIT(file_fcntl, selinux_file_fcntl),
6185 LSM_HOOK_INIT(file_set_fowner, selinux_file_set_fowner),
6186 LSM_HOOK_INIT(file_send_sigiotask, selinux_file_send_sigiotask),
6187 LSM_HOOK_INIT(file_receive, selinux_file_receive),
6188
6189 LSM_HOOK_INIT(file_open, selinux_file_open),
6190
6191 LSM_HOOK_INIT(task_create, selinux_task_create),
6192 LSM_HOOK_INIT(cred_alloc_blank, selinux_cred_alloc_blank),
6193 LSM_HOOK_INIT(cred_free, selinux_cred_free),
6194 LSM_HOOK_INIT(cred_prepare, selinux_cred_prepare),
6195 LSM_HOOK_INIT(cred_transfer, selinux_cred_transfer),
6196 LSM_HOOK_INIT(kernel_act_as, selinux_kernel_act_as),
6197 LSM_HOOK_INIT(kernel_create_files_as, selinux_kernel_create_files_as),
6198 LSM_HOOK_INIT(kernel_module_request, selinux_kernel_module_request),
6199 LSM_HOOK_INIT(kernel_read_file, selinux_kernel_read_file),
6200 LSM_HOOK_INIT(task_setpgid, selinux_task_setpgid),
6201 LSM_HOOK_INIT(task_getpgid, selinux_task_getpgid),
6202 LSM_HOOK_INIT(task_getsid, selinux_task_getsid),
6203 LSM_HOOK_INIT(task_getsecid, selinux_task_getsecid),
6204 LSM_HOOK_INIT(task_setnice, selinux_task_setnice),
6205 LSM_HOOK_INIT(task_setioprio, selinux_task_setioprio),
6206 LSM_HOOK_INIT(task_getioprio, selinux_task_getioprio),
6207 LSM_HOOK_INIT(task_setrlimit, selinux_task_setrlimit),
6208 LSM_HOOK_INIT(task_setscheduler, selinux_task_setscheduler),
6209 LSM_HOOK_INIT(task_getscheduler, selinux_task_getscheduler),
6210 LSM_HOOK_INIT(task_movememory, selinux_task_movememory),
6211 LSM_HOOK_INIT(task_kill, selinux_task_kill),
6212 LSM_HOOK_INIT(task_wait, selinux_task_wait),
6213 LSM_HOOK_INIT(task_to_inode, selinux_task_to_inode),
6214
6215 LSM_HOOK_INIT(ipc_permission, selinux_ipc_permission),
6216 LSM_HOOK_INIT(ipc_getsecid, selinux_ipc_getsecid),
6217
6218 LSM_HOOK_INIT(msg_msg_alloc_security, selinux_msg_msg_alloc_security),
6219 LSM_HOOK_INIT(msg_msg_free_security, selinux_msg_msg_free_security),
6220
6221 LSM_HOOK_INIT(msg_queue_alloc_security,
6222 selinux_msg_queue_alloc_security),
6223 LSM_HOOK_INIT(msg_queue_free_security, selinux_msg_queue_free_security),
6224 LSM_HOOK_INIT(msg_queue_associate, selinux_msg_queue_associate),
6225 LSM_HOOK_INIT(msg_queue_msgctl, selinux_msg_queue_msgctl),
6226 LSM_HOOK_INIT(msg_queue_msgsnd, selinux_msg_queue_msgsnd),
6227 LSM_HOOK_INIT(msg_queue_msgrcv, selinux_msg_queue_msgrcv),
6228
6229 LSM_HOOK_INIT(shm_alloc_security, selinux_shm_alloc_security),
6230 LSM_HOOK_INIT(shm_free_security, selinux_shm_free_security),
6231 LSM_HOOK_INIT(shm_associate, selinux_shm_associate),
6232 LSM_HOOK_INIT(shm_shmctl, selinux_shm_shmctl),
6233 LSM_HOOK_INIT(shm_shmat, selinux_shm_shmat),
6234
6235 LSM_HOOK_INIT(sem_alloc_security, selinux_sem_alloc_security),
6236 LSM_HOOK_INIT(sem_free_security, selinux_sem_free_security),
6237 LSM_HOOK_INIT(sem_associate, selinux_sem_associate),
6238 LSM_HOOK_INIT(sem_semctl, selinux_sem_semctl),
6239 LSM_HOOK_INIT(sem_semop, selinux_sem_semop),
6240
6241 LSM_HOOK_INIT(d_instantiate, selinux_d_instantiate),
6242
6243 LSM_HOOK_INIT(getprocattr, selinux_getprocattr),
6244 LSM_HOOK_INIT(setprocattr, selinux_setprocattr),
6245
6246 LSM_HOOK_INIT(ismaclabel, selinux_ismaclabel),
6247 LSM_HOOK_INIT(secid_to_secctx, selinux_secid_to_secctx),
6248 LSM_HOOK_INIT(secctx_to_secid, selinux_secctx_to_secid),
6249 LSM_HOOK_INIT(release_secctx, selinux_release_secctx),
6250 LSM_HOOK_INIT(inode_invalidate_secctx, selinux_inode_invalidate_secctx),
6251 LSM_HOOK_INIT(inode_notifysecctx, selinux_inode_notifysecctx),
6252 LSM_HOOK_INIT(inode_setsecctx, selinux_inode_setsecctx),
6253 LSM_HOOK_INIT(inode_getsecctx, selinux_inode_getsecctx),
6254
6255 LSM_HOOK_INIT(unix_stream_connect, selinux_socket_unix_stream_connect),
6256 LSM_HOOK_INIT(unix_may_send, selinux_socket_unix_may_send),
6257
6258 LSM_HOOK_INIT(socket_create, selinux_socket_create),
6259 LSM_HOOK_INIT(socket_post_create, selinux_socket_post_create),
6260 LSM_HOOK_INIT(socket_bind, selinux_socket_bind),
6261 LSM_HOOK_INIT(socket_connect, selinux_socket_connect),
6262 LSM_HOOK_INIT(socket_listen, selinux_socket_listen),
6263 LSM_HOOK_INIT(socket_accept, selinux_socket_accept),
6264 LSM_HOOK_INIT(socket_sendmsg, selinux_socket_sendmsg),
6265 LSM_HOOK_INIT(socket_recvmsg, selinux_socket_recvmsg),
6266 LSM_HOOK_INIT(socket_getsockname, selinux_socket_getsockname),
6267 LSM_HOOK_INIT(socket_getpeername, selinux_socket_getpeername),
6268 LSM_HOOK_INIT(socket_getsockopt, selinux_socket_getsockopt),
6269 LSM_HOOK_INIT(socket_setsockopt, selinux_socket_setsockopt),
6270 LSM_HOOK_INIT(socket_shutdown, selinux_socket_shutdown),
6271 LSM_HOOK_INIT(socket_sock_rcv_skb, selinux_socket_sock_rcv_skb),
6272 LSM_HOOK_INIT(socket_getpeersec_stream,
6273 selinux_socket_getpeersec_stream),
6274 LSM_HOOK_INIT(socket_getpeersec_dgram, selinux_socket_getpeersec_dgram),
6275 LSM_HOOK_INIT(sk_alloc_security, selinux_sk_alloc_security),
6276 LSM_HOOK_INIT(sk_free_security, selinux_sk_free_security),
6277 LSM_HOOK_INIT(sk_clone_security, selinux_sk_clone_security),
6278 LSM_HOOK_INIT(sk_getsecid, selinux_sk_getsecid),
6279 LSM_HOOK_INIT(sock_graft, selinux_sock_graft),
6280 LSM_HOOK_INIT(inet_conn_request, selinux_inet_conn_request),
6281 LSM_HOOK_INIT(inet_csk_clone, selinux_inet_csk_clone),
6282 LSM_HOOK_INIT(inet_conn_established, selinux_inet_conn_established),
6283 LSM_HOOK_INIT(secmark_relabel_packet, selinux_secmark_relabel_packet),
6284 LSM_HOOK_INIT(secmark_refcount_inc, selinux_secmark_refcount_inc),
6285 LSM_HOOK_INIT(secmark_refcount_dec, selinux_secmark_refcount_dec),
6286 LSM_HOOK_INIT(req_classify_flow, selinux_req_classify_flow),
6287 LSM_HOOK_INIT(tun_dev_alloc_security, selinux_tun_dev_alloc_security),
6288 LSM_HOOK_INIT(tun_dev_free_security, selinux_tun_dev_free_security),
6289 LSM_HOOK_INIT(tun_dev_create, selinux_tun_dev_create),
6290 LSM_HOOK_INIT(tun_dev_attach_queue, selinux_tun_dev_attach_queue),
6291 LSM_HOOK_INIT(tun_dev_attach, selinux_tun_dev_attach),
6292 LSM_HOOK_INIT(tun_dev_open, selinux_tun_dev_open),
6293
6294#ifdef CONFIG_SECURITY_NETWORK_XFRM
6295 LSM_HOOK_INIT(xfrm_policy_alloc_security, selinux_xfrm_policy_alloc),
6296 LSM_HOOK_INIT(xfrm_policy_clone_security, selinux_xfrm_policy_clone),
6297 LSM_HOOK_INIT(xfrm_policy_free_security, selinux_xfrm_policy_free),
6298 LSM_HOOK_INIT(xfrm_policy_delete_security, selinux_xfrm_policy_delete),
6299 LSM_HOOK_INIT(xfrm_state_alloc, selinux_xfrm_state_alloc),
6300 LSM_HOOK_INIT(xfrm_state_alloc_acquire,
6301 selinux_xfrm_state_alloc_acquire),
6302 LSM_HOOK_INIT(xfrm_state_free_security, selinux_xfrm_state_free),
6303 LSM_HOOK_INIT(xfrm_state_delete_security, selinux_xfrm_state_delete),
6304 LSM_HOOK_INIT(xfrm_policy_lookup, selinux_xfrm_policy_lookup),
6305 LSM_HOOK_INIT(xfrm_state_pol_flow_match,
6306 selinux_xfrm_state_pol_flow_match),
6307 LSM_HOOK_INIT(xfrm_decode_session, selinux_xfrm_decode_session),
6308#endif
6309
6310#ifdef CONFIG_KEYS
6311 LSM_HOOK_INIT(key_alloc, selinux_key_alloc),
6312 LSM_HOOK_INIT(key_free, selinux_key_free),
6313 LSM_HOOK_INIT(key_permission, selinux_key_permission),
6314 LSM_HOOK_INIT(key_getsecurity, selinux_key_getsecurity),
6315#endif
6316
6317#ifdef CONFIG_AUDIT
6318 LSM_HOOK_INIT(audit_rule_init, selinux_audit_rule_init),
6319 LSM_HOOK_INIT(audit_rule_known, selinux_audit_rule_known),
6320 LSM_HOOK_INIT(audit_rule_match, selinux_audit_rule_match),
6321 LSM_HOOK_INIT(audit_rule_free, selinux_audit_rule_free),
6322#endif
6323};
6324
6325static __init int selinux_init(void)
6326{
6327 if (!security_module_enable("selinux")) {
6328 selinux_enabled = 0;
6329 return 0;
6330 }
6331
6332 if (!selinux_enabled) {
6333 printk(KERN_INFO "SELinux: Disabled at boot.\n");
6334 return 0;
6335 }
6336
6337 printk(KERN_INFO "SELinux: Initializing.\n");
6338
6339 /* Set the security state for the initial task. */
6340 cred_init_security();
6341
6342 default_noexec = !(VM_DATA_DEFAULT_FLAGS & VM_EXEC);
6343
6344 sel_inode_cache = kmem_cache_create("selinux_inode_security",
6345 sizeof(struct inode_security_struct),
6346 0, SLAB_PANIC, NULL);
6347 file_security_cache = kmem_cache_create("selinux_file_security",
6348 sizeof(struct file_security_struct),
6349 0, SLAB_PANIC, NULL);
6350 avc_init();
6351
6352 security_add_hooks(selinux_hooks, ARRAY_SIZE(selinux_hooks));
6353
6354 if (avc_add_callback(selinux_netcache_avc_callback, AVC_CALLBACK_RESET))
6355 panic("SELinux: Unable to register AVC netcache callback\n");
6356
6357 if (selinux_enforcing)
6358 printk(KERN_DEBUG "SELinux: Starting in enforcing mode\n");
6359 else
6360 printk(KERN_DEBUG "SELinux: Starting in permissive mode\n");
6361
6362 return 0;
6363}
6364
6365static void delayed_superblock_init(struct super_block *sb, void *unused)
6366{
6367 superblock_doinit(sb, NULL);
6368}
6369
6370void selinux_complete_init(void)
6371{
6372 printk(KERN_DEBUG "SELinux: Completing initialization.\n");
6373
6374 /* Set up any superblocks initialized prior to the policy load. */
6375 printk(KERN_DEBUG "SELinux: Setting up existing superblocks.\n");
6376 iterate_supers(delayed_superblock_init, NULL);
6377}
6378
6379/* SELinux requires early initialization in order to label
6380 all processes and objects when they are created. */
6381security_initcall(selinux_init);
6382
6383#if defined(CONFIG_NETFILTER)
6384
6385static struct nf_hook_ops selinux_nf_ops[] = {
6386 {
6387 .hook = selinux_ipv4_postroute,
6388 .pf = NFPROTO_IPV4,
6389 .hooknum = NF_INET_POST_ROUTING,
6390 .priority = NF_IP_PRI_SELINUX_LAST,
6391 },
6392 {
6393 .hook = selinux_ipv4_forward,
6394 .pf = NFPROTO_IPV4,
6395 .hooknum = NF_INET_FORWARD,
6396 .priority = NF_IP_PRI_SELINUX_FIRST,
6397 },
6398 {
6399 .hook = selinux_ipv4_output,
6400 .pf = NFPROTO_IPV4,
6401 .hooknum = NF_INET_LOCAL_OUT,
6402 .priority = NF_IP_PRI_SELINUX_FIRST,
6403 },
6404#if IS_ENABLED(CONFIG_IPV6)
6405 {
6406 .hook = selinux_ipv6_postroute,
6407 .pf = NFPROTO_IPV6,
6408 .hooknum = NF_INET_POST_ROUTING,
6409 .priority = NF_IP6_PRI_SELINUX_LAST,
6410 },
6411 {
6412 .hook = selinux_ipv6_forward,
6413 .pf = NFPROTO_IPV6,
6414 .hooknum = NF_INET_FORWARD,
6415 .priority = NF_IP6_PRI_SELINUX_FIRST,
6416 },
6417 {
6418 .hook = selinux_ipv6_output,
6419 .pf = NFPROTO_IPV6,
6420 .hooknum = NF_INET_LOCAL_OUT,
6421 .priority = NF_IP6_PRI_SELINUX_FIRST,
6422 },
6423#endif /* IPV6 */
6424};
6425
6426static int __init selinux_nf_ip_init(void)
6427{
6428 int err;
6429
6430 if (!selinux_enabled)
6431 return 0;
6432
6433 printk(KERN_DEBUG "SELinux: Registering netfilter hooks\n");
6434
6435 err = nf_register_hooks(selinux_nf_ops, ARRAY_SIZE(selinux_nf_ops));
6436 if (err)
6437 panic("SELinux: nf_register_hooks: error %d\n", err);
6438
6439 return 0;
6440}
6441
6442__initcall(selinux_nf_ip_init);
6443
6444#ifdef CONFIG_SECURITY_SELINUX_DISABLE
6445static void selinux_nf_ip_exit(void)
6446{
6447 printk(KERN_DEBUG "SELinux: Unregistering netfilter hooks\n");
6448
6449 nf_unregister_hooks(selinux_nf_ops, ARRAY_SIZE(selinux_nf_ops));
6450}
6451#endif
6452
6453#else /* CONFIG_NETFILTER */
6454
6455#ifdef CONFIG_SECURITY_SELINUX_DISABLE
6456#define selinux_nf_ip_exit()
6457#endif
6458
6459#endif /* CONFIG_NETFILTER */
6460
6461#ifdef CONFIG_SECURITY_SELINUX_DISABLE
6462static int selinux_disabled;
6463
6464int selinux_disable(void)
6465{
6466 if (ss_initialized) {
6467 /* Not permitted after initial policy load. */
6468 return -EINVAL;
6469 }
6470
6471 if (selinux_disabled) {
6472 /* Only do this once. */
6473 return -EINVAL;
6474 }
6475
6476 printk(KERN_INFO "SELinux: Disabled at runtime.\n");
6477
6478 selinux_disabled = 1;
6479 selinux_enabled = 0;
6480
6481 security_delete_hooks(selinux_hooks, ARRAY_SIZE(selinux_hooks));
6482
6483 /* Try to destroy the avc node cache */
6484 avc_disable();
6485
6486 /* Unregister netfilter hooks. */
6487 selinux_nf_ip_exit();
6488
6489 /* Unregister selinuxfs. */
6490 exit_sel_fs();
6491
6492 return 0;
6493}
6494#endif