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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@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 mutex_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 inode->i_security = isec;
241
242 return 0;
243}
244
245static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dentry);
246
247/*
248 * Try reloading inode security labels that have been marked as invalid. The
249 * @may_sleep parameter indicates when sleeping and thus reloading labels is
250 * allowed; when set to false, returns ERR_PTR(-ECHILD) when the label is
251 * invalid. The @opt_dentry parameter should be set to a dentry of the inode;
252 * when no dentry is available, set it to NULL instead.
253 */
254static int __inode_security_revalidate(struct inode *inode,
255 struct dentry *opt_dentry,
256 bool may_sleep)
257{
258 struct inode_security_struct *isec = inode->i_security;
259
260 might_sleep_if(may_sleep);
261
262 if (isec->initialized == LABEL_INVALID) {
263 if (!may_sleep)
264 return -ECHILD;
265
266 /*
267 * Try reloading the inode security label. This will fail if
268 * @opt_dentry is NULL and no dentry for this inode can be
269 * found; in that case, continue using the old label.
270 */
271 inode_doinit_with_dentry(inode, opt_dentry);
272 }
273 return 0;
274}
275
276static struct inode_security_struct *inode_security_novalidate(struct inode *inode)
277{
278 return inode->i_security;
279}
280
281static struct inode_security_struct *inode_security_rcu(struct inode *inode, bool rcu)
282{
283 int error;
284
285 error = __inode_security_revalidate(inode, NULL, !rcu);
286 if (error)
287 return ERR_PTR(error);
288 return inode->i_security;
289}
290
291/*
292 * Get the security label of an inode.
293 */
294static struct inode_security_struct *inode_security(struct inode *inode)
295{
296 __inode_security_revalidate(inode, NULL, true);
297 return inode->i_security;
298}
299
300/*
301 * Get the security label of a dentry's backing inode.
302 */
303static struct inode_security_struct *backing_inode_security(struct dentry *dentry)
304{
305 struct inode *inode = d_backing_inode(dentry);
306
307 __inode_security_revalidate(inode, dentry, true);
308 return inode->i_security;
309}
310
311static void inode_free_rcu(struct rcu_head *head)
312{
313 struct inode_security_struct *isec;
314
315 isec = container_of(head, struct inode_security_struct, rcu);
316 kmem_cache_free(sel_inode_cache, isec);
317}
318
319static void inode_free_security(struct inode *inode)
320{
321 struct inode_security_struct *isec = inode->i_security;
322 struct superblock_security_struct *sbsec = inode->i_sb->s_security;
323
324 /*
325 * As not all inode security structures are in a list, we check for
326 * empty list outside of the lock to make sure that we won't waste
327 * time taking a lock doing nothing.
328 *
329 * The list_del_init() function can be safely called more than once.
330 * It should not be possible for this function to be called with
331 * concurrent list_add(), but for better safety against future changes
332 * in the code, we use list_empty_careful() here.
333 */
334 if (!list_empty_careful(&isec->list)) {
335 spin_lock(&sbsec->isec_lock);
336 list_del_init(&isec->list);
337 spin_unlock(&sbsec->isec_lock);
338 }
339
340 /*
341 * The inode may still be referenced in a path walk and
342 * a call to selinux_inode_permission() can be made
343 * after inode_free_security() is called. Ideally, the VFS
344 * wouldn't do this, but fixing that is a much harder
345 * job. For now, simply free the i_security via RCU, and
346 * leave the current inode->i_security pointer intact.
347 * The inode will be freed after the RCU grace period too.
348 */
349 call_rcu(&isec->rcu, inode_free_rcu);
350}
351
352static int file_alloc_security(struct file *file)
353{
354 struct file_security_struct *fsec;
355 u32 sid = current_sid();
356
357 fsec = kmem_cache_zalloc(file_security_cache, GFP_KERNEL);
358 if (!fsec)
359 return -ENOMEM;
360
361 fsec->sid = sid;
362 fsec->fown_sid = sid;
363 file->f_security = fsec;
364
365 return 0;
366}
367
368static void file_free_security(struct file *file)
369{
370 struct file_security_struct *fsec = file->f_security;
371 file->f_security = NULL;
372 kmem_cache_free(file_security_cache, fsec);
373}
374
375static int superblock_alloc_security(struct super_block *sb)
376{
377 struct superblock_security_struct *sbsec;
378
379 sbsec = kzalloc(sizeof(struct superblock_security_struct), GFP_KERNEL);
380 if (!sbsec)
381 return -ENOMEM;
382
383 mutex_init(&sbsec->lock);
384 INIT_LIST_HEAD(&sbsec->isec_head);
385 spin_lock_init(&sbsec->isec_lock);
386 sbsec->sb = sb;
387 sbsec->sid = SECINITSID_UNLABELED;
388 sbsec->def_sid = SECINITSID_FILE;
389 sbsec->mntpoint_sid = SECINITSID_UNLABELED;
390 sb->s_security = sbsec;
391
392 return 0;
393}
394
395static void superblock_free_security(struct super_block *sb)
396{
397 struct superblock_security_struct *sbsec = sb->s_security;
398 sb->s_security = NULL;
399 kfree(sbsec);
400}
401
402/* The file system's label must be initialized prior to use. */
403
404static const char *labeling_behaviors[7] = {
405 "uses xattr",
406 "uses transition SIDs",
407 "uses task SIDs",
408 "uses genfs_contexts",
409 "not configured for labeling",
410 "uses mountpoint labeling",
411 "uses native labeling",
412};
413
414static inline int inode_doinit(struct inode *inode)
415{
416 return inode_doinit_with_dentry(inode, NULL);
417}
418
419enum {
420 Opt_error = -1,
421 Opt_context = 1,
422 Opt_fscontext = 2,
423 Opt_defcontext = 3,
424 Opt_rootcontext = 4,
425 Opt_labelsupport = 5,
426 Opt_nextmntopt = 6,
427};
428
429#define NUM_SEL_MNT_OPTS (Opt_nextmntopt - 1)
430
431static const match_table_t tokens = {
432 {Opt_context, CONTEXT_STR "%s"},
433 {Opt_fscontext, FSCONTEXT_STR "%s"},
434 {Opt_defcontext, DEFCONTEXT_STR "%s"},
435 {Opt_rootcontext, ROOTCONTEXT_STR "%s"},
436 {Opt_labelsupport, LABELSUPP_STR},
437 {Opt_error, NULL},
438};
439
440#define SEL_MOUNT_FAIL_MSG "SELinux: duplicate or incompatible mount options\n"
441
442static int may_context_mount_sb_relabel(u32 sid,
443 struct superblock_security_struct *sbsec,
444 const struct cred *cred)
445{
446 const struct task_security_struct *tsec = cred->security;
447 int rc;
448
449 rc = avc_has_perm(tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM,
450 FILESYSTEM__RELABELFROM, NULL);
451 if (rc)
452 return rc;
453
454 rc = avc_has_perm(tsec->sid, sid, SECCLASS_FILESYSTEM,
455 FILESYSTEM__RELABELTO, NULL);
456 return rc;
457}
458
459static int may_context_mount_inode_relabel(u32 sid,
460 struct superblock_security_struct *sbsec,
461 const struct cred *cred)
462{
463 const struct task_security_struct *tsec = cred->security;
464 int rc;
465 rc = avc_has_perm(tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM,
466 FILESYSTEM__RELABELFROM, NULL);
467 if (rc)
468 return rc;
469
470 rc = avc_has_perm(sid, sbsec->sid, SECCLASS_FILESYSTEM,
471 FILESYSTEM__ASSOCIATE, NULL);
472 return rc;
473}
474
475static int selinux_is_sblabel_mnt(struct super_block *sb)
476{
477 struct superblock_security_struct *sbsec = sb->s_security;
478
479 return sbsec->behavior == SECURITY_FS_USE_XATTR ||
480 sbsec->behavior == SECURITY_FS_USE_TRANS ||
481 sbsec->behavior == SECURITY_FS_USE_TASK ||
482 sbsec->behavior == SECURITY_FS_USE_NATIVE ||
483 /* Special handling. Genfs but also in-core setxattr handler */
484 !strcmp(sb->s_type->name, "sysfs") ||
485 !strcmp(sb->s_type->name, "pstore") ||
486 !strcmp(sb->s_type->name, "debugfs") ||
487 !strcmp(sb->s_type->name, "rootfs");
488}
489
490static int sb_finish_set_opts(struct super_block *sb)
491{
492 struct superblock_security_struct *sbsec = sb->s_security;
493 struct dentry *root = sb->s_root;
494 struct inode *root_inode = d_backing_inode(root);
495 int rc = 0;
496
497 if (sbsec->behavior == SECURITY_FS_USE_XATTR) {
498 /* Make sure that the xattr handler exists and that no
499 error other than -ENODATA is returned by getxattr on
500 the root directory. -ENODATA is ok, as this may be
501 the first boot of the SELinux kernel before we have
502 assigned xattr values to the filesystem. */
503 if (!root_inode->i_op->getxattr) {
504 printk(KERN_WARNING "SELinux: (dev %s, type %s) has no "
505 "xattr support\n", sb->s_id, sb->s_type->name);
506 rc = -EOPNOTSUPP;
507 goto out;
508 }
509 rc = root_inode->i_op->getxattr(root, XATTR_NAME_SELINUX, NULL, 0);
510 if (rc < 0 && rc != -ENODATA) {
511 if (rc == -EOPNOTSUPP)
512 printk(KERN_WARNING "SELinux: (dev %s, type "
513 "%s) has no security xattr handler\n",
514 sb->s_id, sb->s_type->name);
515 else
516 printk(KERN_WARNING "SELinux: (dev %s, type "
517 "%s) getxattr errno %d\n", sb->s_id,
518 sb->s_type->name, -rc);
519 goto out;
520 }
521 }
522
523 if (sbsec->behavior > ARRAY_SIZE(labeling_behaviors))
524 printk(KERN_ERR "SELinux: initialized (dev %s, type %s), unknown behavior\n",
525 sb->s_id, sb->s_type->name);
526
527 sbsec->flags |= SE_SBINITIALIZED;
528 if (selinux_is_sblabel_mnt(sb))
529 sbsec->flags |= SBLABEL_MNT;
530
531 /* Initialize the root inode. */
532 rc = inode_doinit_with_dentry(root_inode, root);
533
534 /* Initialize any other inodes associated with the superblock, e.g.
535 inodes created prior to initial policy load or inodes created
536 during get_sb by a pseudo filesystem that directly
537 populates itself. */
538 spin_lock(&sbsec->isec_lock);
539next_inode:
540 if (!list_empty(&sbsec->isec_head)) {
541 struct inode_security_struct *isec =
542 list_entry(sbsec->isec_head.next,
543 struct inode_security_struct, list);
544 struct inode *inode = isec->inode;
545 list_del_init(&isec->list);
546 spin_unlock(&sbsec->isec_lock);
547 inode = igrab(inode);
548 if (inode) {
549 if (!IS_PRIVATE(inode))
550 inode_doinit(inode);
551 iput(inode);
552 }
553 spin_lock(&sbsec->isec_lock);
554 goto next_inode;
555 }
556 spin_unlock(&sbsec->isec_lock);
557out:
558 return rc;
559}
560
561/*
562 * This function should allow an FS to ask what it's mount security
563 * options were so it can use those later for submounts, displaying
564 * mount options, or whatever.
565 */
566static int selinux_get_mnt_opts(const struct super_block *sb,
567 struct security_mnt_opts *opts)
568{
569 int rc = 0, i;
570 struct superblock_security_struct *sbsec = sb->s_security;
571 char *context = NULL;
572 u32 len;
573 char tmp;
574
575 security_init_mnt_opts(opts);
576
577 if (!(sbsec->flags & SE_SBINITIALIZED))
578 return -EINVAL;
579
580 if (!ss_initialized)
581 return -EINVAL;
582
583 /* make sure we always check enough bits to cover the mask */
584 BUILD_BUG_ON(SE_MNTMASK >= (1 << NUM_SEL_MNT_OPTS));
585
586 tmp = sbsec->flags & SE_MNTMASK;
587 /* count the number of mount options for this sb */
588 for (i = 0; i < NUM_SEL_MNT_OPTS; i++) {
589 if (tmp & 0x01)
590 opts->num_mnt_opts++;
591 tmp >>= 1;
592 }
593 /* Check if the Label support flag is set */
594 if (sbsec->flags & SBLABEL_MNT)
595 opts->num_mnt_opts++;
596
597 opts->mnt_opts = kcalloc(opts->num_mnt_opts, sizeof(char *), GFP_ATOMIC);
598 if (!opts->mnt_opts) {
599 rc = -ENOMEM;
600 goto out_free;
601 }
602
603 opts->mnt_opts_flags = kcalloc(opts->num_mnt_opts, sizeof(int), GFP_ATOMIC);
604 if (!opts->mnt_opts_flags) {
605 rc = -ENOMEM;
606 goto out_free;
607 }
608
609 i = 0;
610 if (sbsec->flags & FSCONTEXT_MNT) {
611 rc = security_sid_to_context(sbsec->sid, &context, &len);
612 if (rc)
613 goto out_free;
614 opts->mnt_opts[i] = context;
615 opts->mnt_opts_flags[i++] = FSCONTEXT_MNT;
616 }
617 if (sbsec->flags & CONTEXT_MNT) {
618 rc = security_sid_to_context(sbsec->mntpoint_sid, &context, &len);
619 if (rc)
620 goto out_free;
621 opts->mnt_opts[i] = context;
622 opts->mnt_opts_flags[i++] = CONTEXT_MNT;
623 }
624 if (sbsec->flags & DEFCONTEXT_MNT) {
625 rc = security_sid_to_context(sbsec->def_sid, &context, &len);
626 if (rc)
627 goto out_free;
628 opts->mnt_opts[i] = context;
629 opts->mnt_opts_flags[i++] = DEFCONTEXT_MNT;
630 }
631 if (sbsec->flags & ROOTCONTEXT_MNT) {
632 struct dentry *root = sbsec->sb->s_root;
633 struct inode_security_struct *isec = backing_inode_security(root);
634
635 rc = security_sid_to_context(isec->sid, &context, &len);
636 if (rc)
637 goto out_free;
638 opts->mnt_opts[i] = context;
639 opts->mnt_opts_flags[i++] = ROOTCONTEXT_MNT;
640 }
641 if (sbsec->flags & SBLABEL_MNT) {
642 opts->mnt_opts[i] = NULL;
643 opts->mnt_opts_flags[i++] = SBLABEL_MNT;
644 }
645
646 BUG_ON(i != opts->num_mnt_opts);
647
648 return 0;
649
650out_free:
651 security_free_mnt_opts(opts);
652 return rc;
653}
654
655static int bad_option(struct superblock_security_struct *sbsec, char flag,
656 u32 old_sid, u32 new_sid)
657{
658 char mnt_flags = sbsec->flags & SE_MNTMASK;
659
660 /* check if the old mount command had the same options */
661 if (sbsec->flags & SE_SBINITIALIZED)
662 if (!(sbsec->flags & flag) ||
663 (old_sid != new_sid))
664 return 1;
665
666 /* check if we were passed the same options twice,
667 * aka someone passed context=a,context=b
668 */
669 if (!(sbsec->flags & SE_SBINITIALIZED))
670 if (mnt_flags & flag)
671 return 1;
672 return 0;
673}
674
675/*
676 * Allow filesystems with binary mount data to explicitly set mount point
677 * labeling information.
678 */
679static int selinux_set_mnt_opts(struct super_block *sb,
680 struct security_mnt_opts *opts,
681 unsigned long kern_flags,
682 unsigned long *set_kern_flags)
683{
684 const struct cred *cred = current_cred();
685 int rc = 0, i;
686 struct superblock_security_struct *sbsec = sb->s_security;
687 const char *name = sb->s_type->name;
688 struct dentry *root = sbsec->sb->s_root;
689 struct inode_security_struct *root_isec = backing_inode_security(root);
690 u32 fscontext_sid = 0, context_sid = 0, rootcontext_sid = 0;
691 u32 defcontext_sid = 0;
692 char **mount_options = opts->mnt_opts;
693 int *flags = opts->mnt_opts_flags;
694 int num_opts = opts->num_mnt_opts;
695
696 mutex_lock(&sbsec->lock);
697
698 if (!ss_initialized) {
699 if (!num_opts) {
700 /* Defer initialization until selinux_complete_init,
701 after the initial policy is loaded and the security
702 server is ready to handle calls. */
703 goto out;
704 }
705 rc = -EINVAL;
706 printk(KERN_WARNING "SELinux: Unable to set superblock options "
707 "before the security server is initialized\n");
708 goto out;
709 }
710 if (kern_flags && !set_kern_flags) {
711 /* Specifying internal flags without providing a place to
712 * place the results is not allowed */
713 rc = -EINVAL;
714 goto out;
715 }
716
717 /*
718 * Binary mount data FS will come through this function twice. Once
719 * from an explicit call and once from the generic calls from the vfs.
720 * Since the generic VFS calls will not contain any security mount data
721 * we need to skip the double mount verification.
722 *
723 * This does open a hole in which we will not notice if the first
724 * mount using this sb set explict options and a second mount using
725 * this sb does not set any security options. (The first options
726 * will be used for both mounts)
727 */
728 if ((sbsec->flags & SE_SBINITIALIZED) && (sb->s_type->fs_flags & FS_BINARY_MOUNTDATA)
729 && (num_opts == 0))
730 goto out;
731
732 /*
733 * parse the mount options, check if they are valid sids.
734 * also check if someone is trying to mount the same sb more
735 * than once with different security options.
736 */
737 for (i = 0; i < num_opts; i++) {
738 u32 sid;
739
740 if (flags[i] == SBLABEL_MNT)
741 continue;
742 rc = security_context_str_to_sid(mount_options[i], &sid, GFP_KERNEL);
743 if (rc) {
744 printk(KERN_WARNING "SELinux: security_context_str_to_sid"
745 "(%s) failed for (dev %s, type %s) errno=%d\n",
746 mount_options[i], sb->s_id, name, rc);
747 goto out;
748 }
749 switch (flags[i]) {
750 case FSCONTEXT_MNT:
751 fscontext_sid = sid;
752
753 if (bad_option(sbsec, FSCONTEXT_MNT, sbsec->sid,
754 fscontext_sid))
755 goto out_double_mount;
756
757 sbsec->flags |= FSCONTEXT_MNT;
758 break;
759 case CONTEXT_MNT:
760 context_sid = sid;
761
762 if (bad_option(sbsec, CONTEXT_MNT, sbsec->mntpoint_sid,
763 context_sid))
764 goto out_double_mount;
765
766 sbsec->flags |= CONTEXT_MNT;
767 break;
768 case ROOTCONTEXT_MNT:
769 rootcontext_sid = sid;
770
771 if (bad_option(sbsec, ROOTCONTEXT_MNT, root_isec->sid,
772 rootcontext_sid))
773 goto out_double_mount;
774
775 sbsec->flags |= ROOTCONTEXT_MNT;
776
777 break;
778 case DEFCONTEXT_MNT:
779 defcontext_sid = sid;
780
781 if (bad_option(sbsec, DEFCONTEXT_MNT, sbsec->def_sid,
782 defcontext_sid))
783 goto out_double_mount;
784
785 sbsec->flags |= DEFCONTEXT_MNT;
786
787 break;
788 default:
789 rc = -EINVAL;
790 goto out;
791 }
792 }
793
794 if (sbsec->flags & SE_SBINITIALIZED) {
795 /* previously mounted with options, but not on this attempt? */
796 if ((sbsec->flags & SE_MNTMASK) && !num_opts)
797 goto out_double_mount;
798 rc = 0;
799 goto out;
800 }
801
802 if (strcmp(sb->s_type->name, "proc") == 0)
803 sbsec->flags |= SE_SBPROC | SE_SBGENFS;
804
805 if (!strcmp(sb->s_type->name, "debugfs") ||
806 !strcmp(sb->s_type->name, "sysfs") ||
807 !strcmp(sb->s_type->name, "pstore"))
808 sbsec->flags |= SE_SBGENFS;
809
810 if (!sbsec->behavior) {
811 /*
812 * Determine the labeling behavior to use for this
813 * filesystem type.
814 */
815 rc = security_fs_use(sb);
816 if (rc) {
817 printk(KERN_WARNING
818 "%s: security_fs_use(%s) returned %d\n",
819 __func__, sb->s_type->name, rc);
820 goto out;
821 }
822 }
823 /* sets the context of the superblock for the fs being mounted. */
824 if (fscontext_sid) {
825 rc = may_context_mount_sb_relabel(fscontext_sid, sbsec, cred);
826 if (rc)
827 goto out;
828
829 sbsec->sid = fscontext_sid;
830 }
831
832 /*
833 * Switch to using mount point labeling behavior.
834 * sets the label used on all file below the mountpoint, and will set
835 * the superblock context if not already set.
836 */
837 if (kern_flags & SECURITY_LSM_NATIVE_LABELS && !context_sid) {
838 sbsec->behavior = SECURITY_FS_USE_NATIVE;
839 *set_kern_flags |= SECURITY_LSM_NATIVE_LABELS;
840 }
841
842 if (context_sid) {
843 if (!fscontext_sid) {
844 rc = may_context_mount_sb_relabel(context_sid, sbsec,
845 cred);
846 if (rc)
847 goto out;
848 sbsec->sid = context_sid;
849 } else {
850 rc = may_context_mount_inode_relabel(context_sid, sbsec,
851 cred);
852 if (rc)
853 goto out;
854 }
855 if (!rootcontext_sid)
856 rootcontext_sid = context_sid;
857
858 sbsec->mntpoint_sid = context_sid;
859 sbsec->behavior = SECURITY_FS_USE_MNTPOINT;
860 }
861
862 if (rootcontext_sid) {
863 rc = may_context_mount_inode_relabel(rootcontext_sid, sbsec,
864 cred);
865 if (rc)
866 goto out;
867
868 root_isec->sid = rootcontext_sid;
869 root_isec->initialized = LABEL_INITIALIZED;
870 }
871
872 if (defcontext_sid) {
873 if (sbsec->behavior != SECURITY_FS_USE_XATTR &&
874 sbsec->behavior != SECURITY_FS_USE_NATIVE) {
875 rc = -EINVAL;
876 printk(KERN_WARNING "SELinux: defcontext option is "
877 "invalid for this filesystem type\n");
878 goto out;
879 }
880
881 if (defcontext_sid != sbsec->def_sid) {
882 rc = may_context_mount_inode_relabel(defcontext_sid,
883 sbsec, cred);
884 if (rc)
885 goto out;
886 }
887
888 sbsec->def_sid = defcontext_sid;
889 }
890
891 rc = sb_finish_set_opts(sb);
892out:
893 mutex_unlock(&sbsec->lock);
894 return rc;
895out_double_mount:
896 rc = -EINVAL;
897 printk(KERN_WARNING "SELinux: mount invalid. Same superblock, different "
898 "security settings for (dev %s, type %s)\n", sb->s_id, name);
899 goto out;
900}
901
902static int selinux_cmp_sb_context(const struct super_block *oldsb,
903 const struct super_block *newsb)
904{
905 struct superblock_security_struct *old = oldsb->s_security;
906 struct superblock_security_struct *new = newsb->s_security;
907 char oldflags = old->flags & SE_MNTMASK;
908 char newflags = new->flags & SE_MNTMASK;
909
910 if (oldflags != newflags)
911 goto mismatch;
912 if ((oldflags & FSCONTEXT_MNT) && old->sid != new->sid)
913 goto mismatch;
914 if ((oldflags & CONTEXT_MNT) && old->mntpoint_sid != new->mntpoint_sid)
915 goto mismatch;
916 if ((oldflags & DEFCONTEXT_MNT) && old->def_sid != new->def_sid)
917 goto mismatch;
918 if (oldflags & ROOTCONTEXT_MNT) {
919 struct inode_security_struct *oldroot = backing_inode_security(oldsb->s_root);
920 struct inode_security_struct *newroot = backing_inode_security(newsb->s_root);
921 if (oldroot->sid != newroot->sid)
922 goto mismatch;
923 }
924 return 0;
925mismatch:
926 printk(KERN_WARNING "SELinux: mount invalid. Same superblock, "
927 "different security settings for (dev %s, "
928 "type %s)\n", newsb->s_id, newsb->s_type->name);
929 return -EBUSY;
930}
931
932static int selinux_sb_clone_mnt_opts(const struct super_block *oldsb,
933 struct super_block *newsb)
934{
935 const struct superblock_security_struct *oldsbsec = oldsb->s_security;
936 struct superblock_security_struct *newsbsec = newsb->s_security;
937
938 int set_fscontext = (oldsbsec->flags & FSCONTEXT_MNT);
939 int set_context = (oldsbsec->flags & CONTEXT_MNT);
940 int set_rootcontext = (oldsbsec->flags & ROOTCONTEXT_MNT);
941
942 /*
943 * if the parent was able to be mounted it clearly had no special lsm
944 * mount options. thus we can safely deal with this superblock later
945 */
946 if (!ss_initialized)
947 return 0;
948
949 /* how can we clone if the old one wasn't set up?? */
950 BUG_ON(!(oldsbsec->flags & SE_SBINITIALIZED));
951
952 /* if fs is reusing a sb, make sure that the contexts match */
953 if (newsbsec->flags & SE_SBINITIALIZED)
954 return selinux_cmp_sb_context(oldsb, newsb);
955
956 mutex_lock(&newsbsec->lock);
957
958 newsbsec->flags = oldsbsec->flags;
959
960 newsbsec->sid = oldsbsec->sid;
961 newsbsec->def_sid = oldsbsec->def_sid;
962 newsbsec->behavior = oldsbsec->behavior;
963
964 if (set_context) {
965 u32 sid = oldsbsec->mntpoint_sid;
966
967 if (!set_fscontext)
968 newsbsec->sid = sid;
969 if (!set_rootcontext) {
970 struct inode_security_struct *newisec = backing_inode_security(newsb->s_root);
971 newisec->sid = sid;
972 }
973 newsbsec->mntpoint_sid = sid;
974 }
975 if (set_rootcontext) {
976 const struct inode_security_struct *oldisec = backing_inode_security(oldsb->s_root);
977 struct inode_security_struct *newisec = backing_inode_security(newsb->s_root);
978
979 newisec->sid = oldisec->sid;
980 }
981
982 sb_finish_set_opts(newsb);
983 mutex_unlock(&newsbsec->lock);
984 return 0;
985}
986
987static int selinux_parse_opts_str(char *options,
988 struct security_mnt_opts *opts)
989{
990 char *p;
991 char *context = NULL, *defcontext = NULL;
992 char *fscontext = NULL, *rootcontext = NULL;
993 int rc, num_mnt_opts = 0;
994
995 opts->num_mnt_opts = 0;
996
997 /* Standard string-based options. */
998 while ((p = strsep(&options, "|")) != NULL) {
999 int token;
1000 substring_t args[MAX_OPT_ARGS];
1001
1002 if (!*p)
1003 continue;
1004
1005 token = match_token(p, tokens, args);
1006
1007 switch (token) {
1008 case Opt_context:
1009 if (context || defcontext) {
1010 rc = -EINVAL;
1011 printk(KERN_WARNING SEL_MOUNT_FAIL_MSG);
1012 goto out_err;
1013 }
1014 context = match_strdup(&args[0]);
1015 if (!context) {
1016 rc = -ENOMEM;
1017 goto out_err;
1018 }
1019 break;
1020
1021 case Opt_fscontext:
1022 if (fscontext) {
1023 rc = -EINVAL;
1024 printk(KERN_WARNING SEL_MOUNT_FAIL_MSG);
1025 goto out_err;
1026 }
1027 fscontext = match_strdup(&args[0]);
1028 if (!fscontext) {
1029 rc = -ENOMEM;
1030 goto out_err;
1031 }
1032 break;
1033
1034 case Opt_rootcontext:
1035 if (rootcontext) {
1036 rc = -EINVAL;
1037 printk(KERN_WARNING SEL_MOUNT_FAIL_MSG);
1038 goto out_err;
1039 }
1040 rootcontext = match_strdup(&args[0]);
1041 if (!rootcontext) {
1042 rc = -ENOMEM;
1043 goto out_err;
1044 }
1045 break;
1046
1047 case Opt_defcontext:
1048 if (context || defcontext) {
1049 rc = -EINVAL;
1050 printk(KERN_WARNING SEL_MOUNT_FAIL_MSG);
1051 goto out_err;
1052 }
1053 defcontext = match_strdup(&args[0]);
1054 if (!defcontext) {
1055 rc = -ENOMEM;
1056 goto out_err;
1057 }
1058 break;
1059 case Opt_labelsupport:
1060 break;
1061 default:
1062 rc = -EINVAL;
1063 printk(KERN_WARNING "SELinux: unknown mount option\n");
1064 goto out_err;
1065
1066 }
1067 }
1068
1069 rc = -ENOMEM;
1070 opts->mnt_opts = kcalloc(NUM_SEL_MNT_OPTS, sizeof(char *), GFP_ATOMIC);
1071 if (!opts->mnt_opts)
1072 goto out_err;
1073
1074 opts->mnt_opts_flags = kcalloc(NUM_SEL_MNT_OPTS, sizeof(int), GFP_ATOMIC);
1075 if (!opts->mnt_opts_flags) {
1076 kfree(opts->mnt_opts);
1077 goto out_err;
1078 }
1079
1080 if (fscontext) {
1081 opts->mnt_opts[num_mnt_opts] = fscontext;
1082 opts->mnt_opts_flags[num_mnt_opts++] = FSCONTEXT_MNT;
1083 }
1084 if (context) {
1085 opts->mnt_opts[num_mnt_opts] = context;
1086 opts->mnt_opts_flags[num_mnt_opts++] = CONTEXT_MNT;
1087 }
1088 if (rootcontext) {
1089 opts->mnt_opts[num_mnt_opts] = rootcontext;
1090 opts->mnt_opts_flags[num_mnt_opts++] = ROOTCONTEXT_MNT;
1091 }
1092 if (defcontext) {
1093 opts->mnt_opts[num_mnt_opts] = defcontext;
1094 opts->mnt_opts_flags[num_mnt_opts++] = DEFCONTEXT_MNT;
1095 }
1096
1097 opts->num_mnt_opts = num_mnt_opts;
1098 return 0;
1099
1100out_err:
1101 kfree(context);
1102 kfree(defcontext);
1103 kfree(fscontext);
1104 kfree(rootcontext);
1105 return rc;
1106}
1107/*
1108 * string mount options parsing and call set the sbsec
1109 */
1110static int superblock_doinit(struct super_block *sb, void *data)
1111{
1112 int rc = 0;
1113 char *options = data;
1114 struct security_mnt_opts opts;
1115
1116 security_init_mnt_opts(&opts);
1117
1118 if (!data)
1119 goto out;
1120
1121 BUG_ON(sb->s_type->fs_flags & FS_BINARY_MOUNTDATA);
1122
1123 rc = selinux_parse_opts_str(options, &opts);
1124 if (rc)
1125 goto out_err;
1126
1127out:
1128 rc = selinux_set_mnt_opts(sb, &opts, 0, NULL);
1129
1130out_err:
1131 security_free_mnt_opts(&opts);
1132 return rc;
1133}
1134
1135static void selinux_write_opts(struct seq_file *m,
1136 struct security_mnt_opts *opts)
1137{
1138 int i;
1139 char *prefix;
1140
1141 for (i = 0; i < opts->num_mnt_opts; i++) {
1142 char *has_comma;
1143
1144 if (opts->mnt_opts[i])
1145 has_comma = strchr(opts->mnt_opts[i], ',');
1146 else
1147 has_comma = NULL;
1148
1149 switch (opts->mnt_opts_flags[i]) {
1150 case CONTEXT_MNT:
1151 prefix = CONTEXT_STR;
1152 break;
1153 case FSCONTEXT_MNT:
1154 prefix = FSCONTEXT_STR;
1155 break;
1156 case ROOTCONTEXT_MNT:
1157 prefix = ROOTCONTEXT_STR;
1158 break;
1159 case DEFCONTEXT_MNT:
1160 prefix = DEFCONTEXT_STR;
1161 break;
1162 case SBLABEL_MNT:
1163 seq_putc(m, ',');
1164 seq_puts(m, LABELSUPP_STR);
1165 continue;
1166 default:
1167 BUG();
1168 return;
1169 };
1170 /* we need a comma before each option */
1171 seq_putc(m, ',');
1172 seq_puts(m, prefix);
1173 if (has_comma)
1174 seq_putc(m, '\"');
1175 seq_escape(m, opts->mnt_opts[i], "\"\n\\");
1176 if (has_comma)
1177 seq_putc(m, '\"');
1178 }
1179}
1180
1181static int selinux_sb_show_options(struct seq_file *m, struct super_block *sb)
1182{
1183 struct security_mnt_opts opts;
1184 int rc;
1185
1186 rc = selinux_get_mnt_opts(sb, &opts);
1187 if (rc) {
1188 /* before policy load we may get EINVAL, don't show anything */
1189 if (rc == -EINVAL)
1190 rc = 0;
1191 return rc;
1192 }
1193
1194 selinux_write_opts(m, &opts);
1195
1196 security_free_mnt_opts(&opts);
1197
1198 return rc;
1199}
1200
1201static inline u16 inode_mode_to_security_class(umode_t mode)
1202{
1203 switch (mode & S_IFMT) {
1204 case S_IFSOCK:
1205 return SECCLASS_SOCK_FILE;
1206 case S_IFLNK:
1207 return SECCLASS_LNK_FILE;
1208 case S_IFREG:
1209 return SECCLASS_FILE;
1210 case S_IFBLK:
1211 return SECCLASS_BLK_FILE;
1212 case S_IFDIR:
1213 return SECCLASS_DIR;
1214 case S_IFCHR:
1215 return SECCLASS_CHR_FILE;
1216 case S_IFIFO:
1217 return SECCLASS_FIFO_FILE;
1218
1219 }
1220
1221 return SECCLASS_FILE;
1222}
1223
1224static inline int default_protocol_stream(int protocol)
1225{
1226 return (protocol == IPPROTO_IP || protocol == IPPROTO_TCP);
1227}
1228
1229static inline int default_protocol_dgram(int protocol)
1230{
1231 return (protocol == IPPROTO_IP || protocol == IPPROTO_UDP);
1232}
1233
1234static inline u16 socket_type_to_security_class(int family, int type, int protocol)
1235{
1236 switch (family) {
1237 case PF_UNIX:
1238 switch (type) {
1239 case SOCK_STREAM:
1240 case SOCK_SEQPACKET:
1241 return SECCLASS_UNIX_STREAM_SOCKET;
1242 case SOCK_DGRAM:
1243 return SECCLASS_UNIX_DGRAM_SOCKET;
1244 }
1245 break;
1246 case PF_INET:
1247 case PF_INET6:
1248 switch (type) {
1249 case SOCK_STREAM:
1250 if (default_protocol_stream(protocol))
1251 return SECCLASS_TCP_SOCKET;
1252 else
1253 return SECCLASS_RAWIP_SOCKET;
1254 case SOCK_DGRAM:
1255 if (default_protocol_dgram(protocol))
1256 return SECCLASS_UDP_SOCKET;
1257 else
1258 return SECCLASS_RAWIP_SOCKET;
1259 case SOCK_DCCP:
1260 return SECCLASS_DCCP_SOCKET;
1261 default:
1262 return SECCLASS_RAWIP_SOCKET;
1263 }
1264 break;
1265 case PF_NETLINK:
1266 switch (protocol) {
1267 case NETLINK_ROUTE:
1268 return SECCLASS_NETLINK_ROUTE_SOCKET;
1269 case NETLINK_SOCK_DIAG:
1270 return SECCLASS_NETLINK_TCPDIAG_SOCKET;
1271 case NETLINK_NFLOG:
1272 return SECCLASS_NETLINK_NFLOG_SOCKET;
1273 case NETLINK_XFRM:
1274 return SECCLASS_NETLINK_XFRM_SOCKET;
1275 case NETLINK_SELINUX:
1276 return SECCLASS_NETLINK_SELINUX_SOCKET;
1277 case NETLINK_ISCSI:
1278 return SECCLASS_NETLINK_ISCSI_SOCKET;
1279 case NETLINK_AUDIT:
1280 return SECCLASS_NETLINK_AUDIT_SOCKET;
1281 case NETLINK_FIB_LOOKUP:
1282 return SECCLASS_NETLINK_FIB_LOOKUP_SOCKET;
1283 case NETLINK_CONNECTOR:
1284 return SECCLASS_NETLINK_CONNECTOR_SOCKET;
1285 case NETLINK_NETFILTER:
1286 return SECCLASS_NETLINK_NETFILTER_SOCKET;
1287 case NETLINK_DNRTMSG:
1288 return SECCLASS_NETLINK_DNRT_SOCKET;
1289 case NETLINK_KOBJECT_UEVENT:
1290 return SECCLASS_NETLINK_KOBJECT_UEVENT_SOCKET;
1291 case NETLINK_GENERIC:
1292 return SECCLASS_NETLINK_GENERIC_SOCKET;
1293 case NETLINK_SCSITRANSPORT:
1294 return SECCLASS_NETLINK_SCSITRANSPORT_SOCKET;
1295 case NETLINK_RDMA:
1296 return SECCLASS_NETLINK_RDMA_SOCKET;
1297 case NETLINK_CRYPTO:
1298 return SECCLASS_NETLINK_CRYPTO_SOCKET;
1299 default:
1300 return SECCLASS_NETLINK_SOCKET;
1301 }
1302 case PF_PACKET:
1303 return SECCLASS_PACKET_SOCKET;
1304 case PF_KEY:
1305 return SECCLASS_KEY_SOCKET;
1306 case PF_APPLETALK:
1307 return SECCLASS_APPLETALK_SOCKET;
1308 }
1309
1310 return SECCLASS_SOCKET;
1311}
1312
1313static int selinux_genfs_get_sid(struct dentry *dentry,
1314 u16 tclass,
1315 u16 flags,
1316 u32 *sid)
1317{
1318 int rc;
1319 struct super_block *sb = dentry->d_inode->i_sb;
1320 char *buffer, *path;
1321
1322 buffer = (char *)__get_free_page(GFP_KERNEL);
1323 if (!buffer)
1324 return -ENOMEM;
1325
1326 path = dentry_path_raw(dentry, buffer, PAGE_SIZE);
1327 if (IS_ERR(path))
1328 rc = PTR_ERR(path);
1329 else {
1330 if (flags & SE_SBPROC) {
1331 /* each process gets a /proc/PID/ entry. Strip off the
1332 * PID part to get a valid selinux labeling.
1333 * e.g. /proc/1/net/rpc/nfs -> /net/rpc/nfs */
1334 while (path[1] >= '0' && path[1] <= '9') {
1335 path[1] = '/';
1336 path++;
1337 }
1338 }
1339 rc = security_genfs_sid(sb->s_type->name, path, tclass, sid);
1340 }
1341 free_page((unsigned long)buffer);
1342 return rc;
1343}
1344
1345/* The inode's security attributes must be initialized before first use. */
1346static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dentry)
1347{
1348 struct superblock_security_struct *sbsec = NULL;
1349 struct inode_security_struct *isec = inode->i_security;
1350 u32 sid;
1351 struct dentry *dentry;
1352#define INITCONTEXTLEN 255
1353 char *context = NULL;
1354 unsigned len = 0;
1355 int rc = 0;
1356
1357 if (isec->initialized == LABEL_INITIALIZED)
1358 goto out;
1359
1360 mutex_lock(&isec->lock);
1361 if (isec->initialized == LABEL_INITIALIZED)
1362 goto out_unlock;
1363
1364 sbsec = inode->i_sb->s_security;
1365 if (!(sbsec->flags & SE_SBINITIALIZED)) {
1366 /* Defer initialization until selinux_complete_init,
1367 after the initial policy is loaded and the security
1368 server is ready to handle calls. */
1369 spin_lock(&sbsec->isec_lock);
1370 if (list_empty(&isec->list))
1371 list_add(&isec->list, &sbsec->isec_head);
1372 spin_unlock(&sbsec->isec_lock);
1373 goto out_unlock;
1374 }
1375
1376 switch (sbsec->behavior) {
1377 case SECURITY_FS_USE_NATIVE:
1378 break;
1379 case SECURITY_FS_USE_XATTR:
1380 if (!inode->i_op->getxattr) {
1381 isec->sid = sbsec->def_sid;
1382 break;
1383 }
1384
1385 /* Need a dentry, since the xattr API requires one.
1386 Life would be simpler if we could just pass the inode. */
1387 if (opt_dentry) {
1388 /* Called from d_instantiate or d_splice_alias. */
1389 dentry = dget(opt_dentry);
1390 } else {
1391 /* Called from selinux_complete_init, try to find a dentry. */
1392 dentry = d_find_alias(inode);
1393 }
1394 if (!dentry) {
1395 /*
1396 * this is can be hit on boot when a file is accessed
1397 * before the policy is loaded. When we load policy we
1398 * may find inodes that have no dentry on the
1399 * sbsec->isec_head list. No reason to complain as these
1400 * will get fixed up the next time we go through
1401 * inode_doinit with a dentry, before these inodes could
1402 * be used again by userspace.
1403 */
1404 goto out_unlock;
1405 }
1406
1407 len = INITCONTEXTLEN;
1408 context = kmalloc(len+1, GFP_NOFS);
1409 if (!context) {
1410 rc = -ENOMEM;
1411 dput(dentry);
1412 goto out_unlock;
1413 }
1414 context[len] = '\0';
1415 rc = inode->i_op->getxattr(dentry, XATTR_NAME_SELINUX,
1416 context, len);
1417 if (rc == -ERANGE) {
1418 kfree(context);
1419
1420 /* Need a larger buffer. Query for the right size. */
1421 rc = inode->i_op->getxattr(dentry, XATTR_NAME_SELINUX,
1422 NULL, 0);
1423 if (rc < 0) {
1424 dput(dentry);
1425 goto out_unlock;
1426 }
1427 len = rc;
1428 context = kmalloc(len+1, GFP_NOFS);
1429 if (!context) {
1430 rc = -ENOMEM;
1431 dput(dentry);
1432 goto out_unlock;
1433 }
1434 context[len] = '\0';
1435 rc = inode->i_op->getxattr(dentry,
1436 XATTR_NAME_SELINUX,
1437 context, len);
1438 }
1439 dput(dentry);
1440 if (rc < 0) {
1441 if (rc != -ENODATA) {
1442 printk(KERN_WARNING "SELinux: %s: getxattr returned "
1443 "%d for dev=%s ino=%ld\n", __func__,
1444 -rc, inode->i_sb->s_id, inode->i_ino);
1445 kfree(context);
1446 goto out_unlock;
1447 }
1448 /* Map ENODATA to the default file SID */
1449 sid = sbsec->def_sid;
1450 rc = 0;
1451 } else {
1452 rc = security_context_to_sid_default(context, rc, &sid,
1453 sbsec->def_sid,
1454 GFP_NOFS);
1455 if (rc) {
1456 char *dev = inode->i_sb->s_id;
1457 unsigned long ino = inode->i_ino;
1458
1459 if (rc == -EINVAL) {
1460 if (printk_ratelimit())
1461 printk(KERN_NOTICE "SELinux: inode=%lu on dev=%s was found to have an invalid "
1462 "context=%s. This indicates you may need to relabel the inode or the "
1463 "filesystem in question.\n", ino, dev, context);
1464 } else {
1465 printk(KERN_WARNING "SELinux: %s: context_to_sid(%s) "
1466 "returned %d for dev=%s ino=%ld\n",
1467 __func__, context, -rc, dev, ino);
1468 }
1469 kfree(context);
1470 /* Leave with the unlabeled SID */
1471 rc = 0;
1472 break;
1473 }
1474 }
1475 kfree(context);
1476 isec->sid = sid;
1477 break;
1478 case SECURITY_FS_USE_TASK:
1479 isec->sid = isec->task_sid;
1480 break;
1481 case SECURITY_FS_USE_TRANS:
1482 /* Default to the fs SID. */
1483 isec->sid = sbsec->sid;
1484
1485 /* Try to obtain a transition SID. */
1486 isec->sclass = inode_mode_to_security_class(inode->i_mode);
1487 rc = security_transition_sid(isec->task_sid, sbsec->sid,
1488 isec->sclass, NULL, &sid);
1489 if (rc)
1490 goto out_unlock;
1491 isec->sid = sid;
1492 break;
1493 case SECURITY_FS_USE_MNTPOINT:
1494 isec->sid = sbsec->mntpoint_sid;
1495 break;
1496 default:
1497 /* Default to the fs superblock SID. */
1498 isec->sid = sbsec->sid;
1499
1500 if ((sbsec->flags & SE_SBGENFS) && !S_ISLNK(inode->i_mode)) {
1501 /* We must have a dentry to determine the label on
1502 * procfs inodes */
1503 if (opt_dentry)
1504 /* Called from d_instantiate or
1505 * d_splice_alias. */
1506 dentry = dget(opt_dentry);
1507 else
1508 /* Called from selinux_complete_init, try to
1509 * find a dentry. */
1510 dentry = d_find_alias(inode);
1511 /*
1512 * This can be hit on boot when a file is accessed
1513 * before the policy is loaded. When we load policy we
1514 * may find inodes that have no dentry on the
1515 * sbsec->isec_head list. No reason to complain as
1516 * these will get fixed up the next time we go through
1517 * inode_doinit() with a dentry, before these inodes
1518 * could be used again by userspace.
1519 */
1520 if (!dentry)
1521 goto out_unlock;
1522 isec->sclass = inode_mode_to_security_class(inode->i_mode);
1523 rc = selinux_genfs_get_sid(dentry, isec->sclass,
1524 sbsec->flags, &sid);
1525 dput(dentry);
1526 if (rc)
1527 goto out_unlock;
1528 isec->sid = sid;
1529 }
1530 break;
1531 }
1532
1533 isec->initialized = LABEL_INITIALIZED;
1534
1535out_unlock:
1536 mutex_unlock(&isec->lock);
1537out:
1538 if (isec->sclass == SECCLASS_FILE)
1539 isec->sclass = inode_mode_to_security_class(inode->i_mode);
1540 return rc;
1541}
1542
1543/* Convert a Linux signal to an access vector. */
1544static inline u32 signal_to_av(int sig)
1545{
1546 u32 perm = 0;
1547
1548 switch (sig) {
1549 case SIGCHLD:
1550 /* Commonly granted from child to parent. */
1551 perm = PROCESS__SIGCHLD;
1552 break;
1553 case SIGKILL:
1554 /* Cannot be caught or ignored */
1555 perm = PROCESS__SIGKILL;
1556 break;
1557 case SIGSTOP:
1558 /* Cannot be caught or ignored */
1559 perm = PROCESS__SIGSTOP;
1560 break;
1561 default:
1562 /* All other signals. */
1563 perm = PROCESS__SIGNAL;
1564 break;
1565 }
1566
1567 return perm;
1568}
1569
1570/*
1571 * Check permission between a pair of credentials
1572 * fork check, ptrace check, etc.
1573 */
1574static int cred_has_perm(const struct cred *actor,
1575 const struct cred *target,
1576 u32 perms)
1577{
1578 u32 asid = cred_sid(actor), tsid = cred_sid(target);
1579
1580 return avc_has_perm(asid, tsid, SECCLASS_PROCESS, perms, NULL);
1581}
1582
1583/*
1584 * Check permission between a pair of tasks, e.g. signal checks,
1585 * fork check, ptrace check, etc.
1586 * tsk1 is the actor and tsk2 is the target
1587 * - this uses the default subjective creds of tsk1
1588 */
1589static int task_has_perm(const struct task_struct *tsk1,
1590 const struct task_struct *tsk2,
1591 u32 perms)
1592{
1593 const struct task_security_struct *__tsec1, *__tsec2;
1594 u32 sid1, sid2;
1595
1596 rcu_read_lock();
1597 __tsec1 = __task_cred(tsk1)->security; sid1 = __tsec1->sid;
1598 __tsec2 = __task_cred(tsk2)->security; sid2 = __tsec2->sid;
1599 rcu_read_unlock();
1600 return avc_has_perm(sid1, sid2, SECCLASS_PROCESS, perms, NULL);
1601}
1602
1603/*
1604 * Check permission between current and another task, e.g. signal checks,
1605 * fork check, ptrace check, etc.
1606 * current is the actor and tsk2 is the target
1607 * - this uses current's subjective creds
1608 */
1609static int current_has_perm(const struct task_struct *tsk,
1610 u32 perms)
1611{
1612 u32 sid, tsid;
1613
1614 sid = current_sid();
1615 tsid = task_sid(tsk);
1616 return avc_has_perm(sid, tsid, SECCLASS_PROCESS, perms, NULL);
1617}
1618
1619#if CAP_LAST_CAP > 63
1620#error Fix SELinux to handle capabilities > 63.
1621#endif
1622
1623/* Check whether a task is allowed to use a capability. */
1624static int cred_has_capability(const struct cred *cred,
1625 int cap, int audit)
1626{
1627 struct common_audit_data ad;
1628 struct av_decision avd;
1629 u16 sclass;
1630 u32 sid = cred_sid(cred);
1631 u32 av = CAP_TO_MASK(cap);
1632 int rc;
1633
1634 ad.type = LSM_AUDIT_DATA_CAP;
1635 ad.u.cap = cap;
1636
1637 switch (CAP_TO_INDEX(cap)) {
1638 case 0:
1639 sclass = SECCLASS_CAPABILITY;
1640 break;
1641 case 1:
1642 sclass = SECCLASS_CAPABILITY2;
1643 break;
1644 default:
1645 printk(KERN_ERR
1646 "SELinux: out of range capability %d\n", cap);
1647 BUG();
1648 return -EINVAL;
1649 }
1650
1651 rc = avc_has_perm_noaudit(sid, sid, sclass, av, 0, &avd);
1652 if (audit == SECURITY_CAP_AUDIT) {
1653 int rc2 = avc_audit(sid, sid, sclass, av, &avd, rc, &ad, 0);
1654 if (rc2)
1655 return rc2;
1656 }
1657 return rc;
1658}
1659
1660/* Check whether a task is allowed to use a system operation. */
1661static int task_has_system(struct task_struct *tsk,
1662 u32 perms)
1663{
1664 u32 sid = task_sid(tsk);
1665
1666 return avc_has_perm(sid, SECINITSID_KERNEL,
1667 SECCLASS_SYSTEM, perms, NULL);
1668}
1669
1670/* Check whether a task has a particular permission to an inode.
1671 The 'adp' parameter is optional and allows other audit
1672 data to be passed (e.g. the dentry). */
1673static int inode_has_perm(const struct cred *cred,
1674 struct inode *inode,
1675 u32 perms,
1676 struct common_audit_data *adp)
1677{
1678 struct inode_security_struct *isec;
1679 u32 sid;
1680
1681 validate_creds(cred);
1682
1683 if (unlikely(IS_PRIVATE(inode)))
1684 return 0;
1685
1686 sid = cred_sid(cred);
1687 isec = inode->i_security;
1688
1689 return avc_has_perm(sid, isec->sid, isec->sclass, perms, adp);
1690}
1691
1692/* Same as inode_has_perm, but pass explicit audit data containing
1693 the dentry to help the auditing code to more easily generate the
1694 pathname if needed. */
1695static inline int dentry_has_perm(const struct cred *cred,
1696 struct dentry *dentry,
1697 u32 av)
1698{
1699 struct inode *inode = d_backing_inode(dentry);
1700 struct common_audit_data ad;
1701
1702 ad.type = LSM_AUDIT_DATA_DENTRY;
1703 ad.u.dentry = dentry;
1704 __inode_security_revalidate(inode, dentry, true);
1705 return inode_has_perm(cred, inode, av, &ad);
1706}
1707
1708/* Same as inode_has_perm, but pass explicit audit data containing
1709 the path to help the auditing code to more easily generate the
1710 pathname if needed. */
1711static inline int path_has_perm(const struct cred *cred,
1712 const struct path *path,
1713 u32 av)
1714{
1715 struct inode *inode = d_backing_inode(path->dentry);
1716 struct common_audit_data ad;
1717
1718 ad.type = LSM_AUDIT_DATA_PATH;
1719 ad.u.path = *path;
1720 __inode_security_revalidate(inode, path->dentry, true);
1721 return inode_has_perm(cred, inode, av, &ad);
1722}
1723
1724/* Same as path_has_perm, but uses the inode from the file struct. */
1725static inline int file_path_has_perm(const struct cred *cred,
1726 struct file *file,
1727 u32 av)
1728{
1729 struct common_audit_data ad;
1730
1731 ad.type = LSM_AUDIT_DATA_PATH;
1732 ad.u.path = file->f_path;
1733 return inode_has_perm(cred, file_inode(file), av, &ad);
1734}
1735
1736/* Check whether a task can use an open file descriptor to
1737 access an inode in a given way. Check access to the
1738 descriptor itself, and then use dentry_has_perm to
1739 check a particular permission to the file.
1740 Access to the descriptor is implicitly granted if it
1741 has the same SID as the process. If av is zero, then
1742 access to the file is not checked, e.g. for cases
1743 where only the descriptor is affected like seek. */
1744static int file_has_perm(const struct cred *cred,
1745 struct file *file,
1746 u32 av)
1747{
1748 struct file_security_struct *fsec = file->f_security;
1749 struct inode *inode = file_inode(file);
1750 struct common_audit_data ad;
1751 u32 sid = cred_sid(cred);
1752 int rc;
1753
1754 ad.type = LSM_AUDIT_DATA_PATH;
1755 ad.u.path = file->f_path;
1756
1757 if (sid != fsec->sid) {
1758 rc = avc_has_perm(sid, fsec->sid,
1759 SECCLASS_FD,
1760 FD__USE,
1761 &ad);
1762 if (rc)
1763 goto out;
1764 }
1765
1766 /* av is zero if only checking access to the descriptor. */
1767 rc = 0;
1768 if (av)
1769 rc = inode_has_perm(cred, inode, av, &ad);
1770
1771out:
1772 return rc;
1773}
1774
1775/*
1776 * Determine the label for an inode that might be unioned.
1777 */
1778static int selinux_determine_inode_label(struct inode *dir,
1779 const struct qstr *name,
1780 u16 tclass,
1781 u32 *_new_isid)
1782{
1783 const struct superblock_security_struct *sbsec = dir->i_sb->s_security;
1784 const struct inode_security_struct *dsec = inode_security(dir);
1785 const struct task_security_struct *tsec = current_security();
1786
1787 if ((sbsec->flags & SE_SBINITIALIZED) &&
1788 (sbsec->behavior == SECURITY_FS_USE_MNTPOINT)) {
1789 *_new_isid = sbsec->mntpoint_sid;
1790 } else if ((sbsec->flags & SBLABEL_MNT) &&
1791 tsec->create_sid) {
1792 *_new_isid = tsec->create_sid;
1793 } else {
1794 return security_transition_sid(tsec->sid, dsec->sid, tclass,
1795 name, _new_isid);
1796 }
1797
1798 return 0;
1799}
1800
1801/* Check whether a task can create a file. */
1802static int may_create(struct inode *dir,
1803 struct dentry *dentry,
1804 u16 tclass)
1805{
1806 const struct task_security_struct *tsec = current_security();
1807 struct inode_security_struct *dsec;
1808 struct superblock_security_struct *sbsec;
1809 u32 sid, newsid;
1810 struct common_audit_data ad;
1811 int rc;
1812
1813 dsec = inode_security(dir);
1814 sbsec = dir->i_sb->s_security;
1815
1816 sid = tsec->sid;
1817
1818 ad.type = LSM_AUDIT_DATA_DENTRY;
1819 ad.u.dentry = dentry;
1820
1821 rc = avc_has_perm(sid, dsec->sid, SECCLASS_DIR,
1822 DIR__ADD_NAME | DIR__SEARCH,
1823 &ad);
1824 if (rc)
1825 return rc;
1826
1827 rc = selinux_determine_inode_label(dir, &dentry->d_name, tclass,
1828 &newsid);
1829 if (rc)
1830 return rc;
1831
1832 rc = avc_has_perm(sid, newsid, tclass, FILE__CREATE, &ad);
1833 if (rc)
1834 return rc;
1835
1836 return avc_has_perm(newsid, sbsec->sid,
1837 SECCLASS_FILESYSTEM,
1838 FILESYSTEM__ASSOCIATE, &ad);
1839}
1840
1841/* Check whether a task can create a key. */
1842static int may_create_key(u32 ksid,
1843 struct task_struct *ctx)
1844{
1845 u32 sid = task_sid(ctx);
1846
1847 return avc_has_perm(sid, ksid, SECCLASS_KEY, KEY__CREATE, NULL);
1848}
1849
1850#define MAY_LINK 0
1851#define MAY_UNLINK 1
1852#define MAY_RMDIR 2
1853
1854/* Check whether a task can link, unlink, or rmdir a file/directory. */
1855static int may_link(struct inode *dir,
1856 struct dentry *dentry,
1857 int kind)
1858
1859{
1860 struct inode_security_struct *dsec, *isec;
1861 struct common_audit_data ad;
1862 u32 sid = current_sid();
1863 u32 av;
1864 int rc;
1865
1866 dsec = inode_security(dir);
1867 isec = backing_inode_security(dentry);
1868
1869 ad.type = LSM_AUDIT_DATA_DENTRY;
1870 ad.u.dentry = dentry;
1871
1872 av = DIR__SEARCH;
1873 av |= (kind ? DIR__REMOVE_NAME : DIR__ADD_NAME);
1874 rc = avc_has_perm(sid, dsec->sid, SECCLASS_DIR, av, &ad);
1875 if (rc)
1876 return rc;
1877
1878 switch (kind) {
1879 case MAY_LINK:
1880 av = FILE__LINK;
1881 break;
1882 case MAY_UNLINK:
1883 av = FILE__UNLINK;
1884 break;
1885 case MAY_RMDIR:
1886 av = DIR__RMDIR;
1887 break;
1888 default:
1889 printk(KERN_WARNING "SELinux: %s: unrecognized kind %d\n",
1890 __func__, kind);
1891 return 0;
1892 }
1893
1894 rc = avc_has_perm(sid, isec->sid, isec->sclass, av, &ad);
1895 return rc;
1896}
1897
1898static inline int may_rename(struct inode *old_dir,
1899 struct dentry *old_dentry,
1900 struct inode *new_dir,
1901 struct dentry *new_dentry)
1902{
1903 struct inode_security_struct *old_dsec, *new_dsec, *old_isec, *new_isec;
1904 struct common_audit_data ad;
1905 u32 sid = current_sid();
1906 u32 av;
1907 int old_is_dir, new_is_dir;
1908 int rc;
1909
1910 old_dsec = inode_security(old_dir);
1911 old_isec = backing_inode_security(old_dentry);
1912 old_is_dir = d_is_dir(old_dentry);
1913 new_dsec = inode_security(new_dir);
1914
1915 ad.type = LSM_AUDIT_DATA_DENTRY;
1916
1917 ad.u.dentry = old_dentry;
1918 rc = avc_has_perm(sid, old_dsec->sid, SECCLASS_DIR,
1919 DIR__REMOVE_NAME | DIR__SEARCH, &ad);
1920 if (rc)
1921 return rc;
1922 rc = avc_has_perm(sid, old_isec->sid,
1923 old_isec->sclass, FILE__RENAME, &ad);
1924 if (rc)
1925 return rc;
1926 if (old_is_dir && new_dir != old_dir) {
1927 rc = avc_has_perm(sid, old_isec->sid,
1928 old_isec->sclass, DIR__REPARENT, &ad);
1929 if (rc)
1930 return rc;
1931 }
1932
1933 ad.u.dentry = new_dentry;
1934 av = DIR__ADD_NAME | DIR__SEARCH;
1935 if (d_is_positive(new_dentry))
1936 av |= DIR__REMOVE_NAME;
1937 rc = avc_has_perm(sid, new_dsec->sid, SECCLASS_DIR, av, &ad);
1938 if (rc)
1939 return rc;
1940 if (d_is_positive(new_dentry)) {
1941 new_isec = backing_inode_security(new_dentry);
1942 new_is_dir = d_is_dir(new_dentry);
1943 rc = avc_has_perm(sid, new_isec->sid,
1944 new_isec->sclass,
1945 (new_is_dir ? DIR__RMDIR : FILE__UNLINK), &ad);
1946 if (rc)
1947 return rc;
1948 }
1949
1950 return 0;
1951}
1952
1953/* Check whether a task can perform a filesystem operation. */
1954static int superblock_has_perm(const struct cred *cred,
1955 struct super_block *sb,
1956 u32 perms,
1957 struct common_audit_data *ad)
1958{
1959 struct superblock_security_struct *sbsec;
1960 u32 sid = cred_sid(cred);
1961
1962 sbsec = sb->s_security;
1963 return avc_has_perm(sid, sbsec->sid, SECCLASS_FILESYSTEM, perms, ad);
1964}
1965
1966/* Convert a Linux mode and permission mask to an access vector. */
1967static inline u32 file_mask_to_av(int mode, int mask)
1968{
1969 u32 av = 0;
1970
1971 if (!S_ISDIR(mode)) {
1972 if (mask & MAY_EXEC)
1973 av |= FILE__EXECUTE;
1974 if (mask & MAY_READ)
1975 av |= FILE__READ;
1976
1977 if (mask & MAY_APPEND)
1978 av |= FILE__APPEND;
1979 else if (mask & MAY_WRITE)
1980 av |= FILE__WRITE;
1981
1982 } else {
1983 if (mask & MAY_EXEC)
1984 av |= DIR__SEARCH;
1985 if (mask & MAY_WRITE)
1986 av |= DIR__WRITE;
1987 if (mask & MAY_READ)
1988 av |= DIR__READ;
1989 }
1990
1991 return av;
1992}
1993
1994/* Convert a Linux file to an access vector. */
1995static inline u32 file_to_av(struct file *file)
1996{
1997 u32 av = 0;
1998
1999 if (file->f_mode & FMODE_READ)
2000 av |= FILE__READ;
2001 if (file->f_mode & FMODE_WRITE) {
2002 if (file->f_flags & O_APPEND)
2003 av |= FILE__APPEND;
2004 else
2005 av |= FILE__WRITE;
2006 }
2007 if (!av) {
2008 /*
2009 * Special file opened with flags 3 for ioctl-only use.
2010 */
2011 av = FILE__IOCTL;
2012 }
2013
2014 return av;
2015}
2016
2017/*
2018 * Convert a file to an access vector and include the correct open
2019 * open permission.
2020 */
2021static inline u32 open_file_to_av(struct file *file)
2022{
2023 u32 av = file_to_av(file);
2024
2025 if (selinux_policycap_openperm)
2026 av |= FILE__OPEN;
2027
2028 return av;
2029}
2030
2031/* Hook functions begin here. */
2032
2033static int selinux_binder_set_context_mgr(struct task_struct *mgr)
2034{
2035 u32 mysid = current_sid();
2036 u32 mgrsid = task_sid(mgr);
2037
2038 return avc_has_perm(mysid, mgrsid, SECCLASS_BINDER,
2039 BINDER__SET_CONTEXT_MGR, NULL);
2040}
2041
2042static int selinux_binder_transaction(struct task_struct *from,
2043 struct task_struct *to)
2044{
2045 u32 mysid = current_sid();
2046 u32 fromsid = task_sid(from);
2047 u32 tosid = task_sid(to);
2048 int rc;
2049
2050 if (mysid != fromsid) {
2051 rc = avc_has_perm(mysid, fromsid, SECCLASS_BINDER,
2052 BINDER__IMPERSONATE, NULL);
2053 if (rc)
2054 return rc;
2055 }
2056
2057 return avc_has_perm(fromsid, tosid, SECCLASS_BINDER, BINDER__CALL,
2058 NULL);
2059}
2060
2061static int selinux_binder_transfer_binder(struct task_struct *from,
2062 struct task_struct *to)
2063{
2064 u32 fromsid = task_sid(from);
2065 u32 tosid = task_sid(to);
2066
2067 return avc_has_perm(fromsid, tosid, SECCLASS_BINDER, BINDER__TRANSFER,
2068 NULL);
2069}
2070
2071static int selinux_binder_transfer_file(struct task_struct *from,
2072 struct task_struct *to,
2073 struct file *file)
2074{
2075 u32 sid = task_sid(to);
2076 struct file_security_struct *fsec = file->f_security;
2077 struct dentry *dentry = file->f_path.dentry;
2078 struct inode_security_struct *isec = backing_inode_security(dentry);
2079 struct common_audit_data ad;
2080 int rc;
2081
2082 ad.type = LSM_AUDIT_DATA_PATH;
2083 ad.u.path = file->f_path;
2084
2085 if (sid != fsec->sid) {
2086 rc = avc_has_perm(sid, fsec->sid,
2087 SECCLASS_FD,
2088 FD__USE,
2089 &ad);
2090 if (rc)
2091 return rc;
2092 }
2093
2094 if (unlikely(IS_PRIVATE(d_backing_inode(dentry))))
2095 return 0;
2096
2097 return avc_has_perm(sid, isec->sid, isec->sclass, file_to_av(file),
2098 &ad);
2099}
2100
2101static int selinux_ptrace_access_check(struct task_struct *child,
2102 unsigned int mode)
2103{
2104 if (mode & PTRACE_MODE_READ) {
2105 u32 sid = current_sid();
2106 u32 csid = task_sid(child);
2107 return avc_has_perm(sid, csid, SECCLASS_FILE, FILE__READ, NULL);
2108 }
2109
2110 return current_has_perm(child, PROCESS__PTRACE);
2111}
2112
2113static int selinux_ptrace_traceme(struct task_struct *parent)
2114{
2115 return task_has_perm(parent, current, PROCESS__PTRACE);
2116}
2117
2118static int selinux_capget(struct task_struct *target, kernel_cap_t *effective,
2119 kernel_cap_t *inheritable, kernel_cap_t *permitted)
2120{
2121 return current_has_perm(target, PROCESS__GETCAP);
2122}
2123
2124static int selinux_capset(struct cred *new, const struct cred *old,
2125 const kernel_cap_t *effective,
2126 const kernel_cap_t *inheritable,
2127 const kernel_cap_t *permitted)
2128{
2129 return cred_has_perm(old, new, PROCESS__SETCAP);
2130}
2131
2132/*
2133 * (This comment used to live with the selinux_task_setuid hook,
2134 * which was removed).
2135 *
2136 * Since setuid only affects the current process, and since the SELinux
2137 * controls are not based on the Linux identity attributes, SELinux does not
2138 * need to control this operation. However, SELinux does control the use of
2139 * the CAP_SETUID and CAP_SETGID capabilities using the capable hook.
2140 */
2141
2142static int selinux_capable(const struct cred *cred, struct user_namespace *ns,
2143 int cap, int audit)
2144{
2145 return cred_has_capability(cred, cap, audit);
2146}
2147
2148static int selinux_quotactl(int cmds, int type, int id, struct super_block *sb)
2149{
2150 const struct cred *cred = current_cred();
2151 int rc = 0;
2152
2153 if (!sb)
2154 return 0;
2155
2156 switch (cmds) {
2157 case Q_SYNC:
2158 case Q_QUOTAON:
2159 case Q_QUOTAOFF:
2160 case Q_SETINFO:
2161 case Q_SETQUOTA:
2162 rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAMOD, NULL);
2163 break;
2164 case Q_GETFMT:
2165 case Q_GETINFO:
2166 case Q_GETQUOTA:
2167 rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAGET, NULL);
2168 break;
2169 default:
2170 rc = 0; /* let the kernel handle invalid cmds */
2171 break;
2172 }
2173 return rc;
2174}
2175
2176static int selinux_quota_on(struct dentry *dentry)
2177{
2178 const struct cred *cred = current_cred();
2179
2180 return dentry_has_perm(cred, dentry, FILE__QUOTAON);
2181}
2182
2183static int selinux_syslog(int type)
2184{
2185 int rc;
2186
2187 switch (type) {
2188 case SYSLOG_ACTION_READ_ALL: /* Read last kernel messages */
2189 case SYSLOG_ACTION_SIZE_BUFFER: /* Return size of the log buffer */
2190 rc = task_has_system(current, SYSTEM__SYSLOG_READ);
2191 break;
2192 case SYSLOG_ACTION_CONSOLE_OFF: /* Disable logging to console */
2193 case SYSLOG_ACTION_CONSOLE_ON: /* Enable logging to console */
2194 /* Set level of messages printed to console */
2195 case SYSLOG_ACTION_CONSOLE_LEVEL:
2196 rc = task_has_system(current, SYSTEM__SYSLOG_CONSOLE);
2197 break;
2198 case SYSLOG_ACTION_CLOSE: /* Close log */
2199 case SYSLOG_ACTION_OPEN: /* Open log */
2200 case SYSLOG_ACTION_READ: /* Read from log */
2201 case SYSLOG_ACTION_READ_CLEAR: /* Read/clear last kernel messages */
2202 case SYSLOG_ACTION_CLEAR: /* Clear ring buffer */
2203 default:
2204 rc = task_has_system(current, SYSTEM__SYSLOG_MOD);
2205 break;
2206 }
2207 return rc;
2208}
2209
2210/*
2211 * Check that a process has enough memory to allocate a new virtual
2212 * mapping. 0 means there is enough memory for the allocation to
2213 * succeed and -ENOMEM implies there is not.
2214 *
2215 * Do not audit the selinux permission check, as this is applied to all
2216 * processes that allocate mappings.
2217 */
2218static int selinux_vm_enough_memory(struct mm_struct *mm, long pages)
2219{
2220 int rc, cap_sys_admin = 0;
2221
2222 rc = cred_has_capability(current_cred(), CAP_SYS_ADMIN,
2223 SECURITY_CAP_NOAUDIT);
2224 if (rc == 0)
2225 cap_sys_admin = 1;
2226
2227 return cap_sys_admin;
2228}
2229
2230/* binprm security operations */
2231
2232static int check_nnp_nosuid(const struct linux_binprm *bprm,
2233 const struct task_security_struct *old_tsec,
2234 const struct task_security_struct *new_tsec)
2235{
2236 int nnp = (bprm->unsafe & LSM_UNSAFE_NO_NEW_PRIVS);
2237 int nosuid = (bprm->file->f_path.mnt->mnt_flags & MNT_NOSUID);
2238 int rc;
2239
2240 if (!nnp && !nosuid)
2241 return 0; /* neither NNP nor nosuid */
2242
2243 if (new_tsec->sid == old_tsec->sid)
2244 return 0; /* No change in credentials */
2245
2246 /*
2247 * The only transitions we permit under NNP or nosuid
2248 * are transitions to bounded SIDs, i.e. SIDs that are
2249 * guaranteed to only be allowed a subset of the permissions
2250 * of the current SID.
2251 */
2252 rc = security_bounded_transition(old_tsec->sid, new_tsec->sid);
2253 if (rc) {
2254 /*
2255 * On failure, preserve the errno values for NNP vs nosuid.
2256 * NNP: Operation not permitted for caller.
2257 * nosuid: Permission denied to file.
2258 */
2259 if (nnp)
2260 return -EPERM;
2261 else
2262 return -EACCES;
2263 }
2264 return 0;
2265}
2266
2267static int selinux_bprm_set_creds(struct linux_binprm *bprm)
2268{
2269 const struct task_security_struct *old_tsec;
2270 struct task_security_struct *new_tsec;
2271 struct inode_security_struct *isec;
2272 struct common_audit_data ad;
2273 struct inode *inode = file_inode(bprm->file);
2274 int rc;
2275
2276 /* SELinux context only depends on initial program or script and not
2277 * the script interpreter */
2278 if (bprm->cred_prepared)
2279 return 0;
2280
2281 old_tsec = current_security();
2282 new_tsec = bprm->cred->security;
2283 isec = inode_security(inode);
2284
2285 /* Default to the current task SID. */
2286 new_tsec->sid = old_tsec->sid;
2287 new_tsec->osid = old_tsec->sid;
2288
2289 /* Reset fs, key, and sock SIDs on execve. */
2290 new_tsec->create_sid = 0;
2291 new_tsec->keycreate_sid = 0;
2292 new_tsec->sockcreate_sid = 0;
2293
2294 if (old_tsec->exec_sid) {
2295 new_tsec->sid = old_tsec->exec_sid;
2296 /* Reset exec SID on execve. */
2297 new_tsec->exec_sid = 0;
2298
2299 /* Fail on NNP or nosuid if not an allowed transition. */
2300 rc = check_nnp_nosuid(bprm, old_tsec, new_tsec);
2301 if (rc)
2302 return rc;
2303 } else {
2304 /* Check for a default transition on this program. */
2305 rc = security_transition_sid(old_tsec->sid, isec->sid,
2306 SECCLASS_PROCESS, NULL,
2307 &new_tsec->sid);
2308 if (rc)
2309 return rc;
2310
2311 /*
2312 * Fallback to old SID on NNP or nosuid if not an allowed
2313 * transition.
2314 */
2315 rc = check_nnp_nosuid(bprm, old_tsec, new_tsec);
2316 if (rc)
2317 new_tsec->sid = old_tsec->sid;
2318 }
2319
2320 ad.type = LSM_AUDIT_DATA_PATH;
2321 ad.u.path = bprm->file->f_path;
2322
2323 if (new_tsec->sid == old_tsec->sid) {
2324 rc = avc_has_perm(old_tsec->sid, isec->sid,
2325 SECCLASS_FILE, FILE__EXECUTE_NO_TRANS, &ad);
2326 if (rc)
2327 return rc;
2328 } else {
2329 /* Check permissions for the transition. */
2330 rc = avc_has_perm(old_tsec->sid, new_tsec->sid,
2331 SECCLASS_PROCESS, PROCESS__TRANSITION, &ad);
2332 if (rc)
2333 return rc;
2334
2335 rc = avc_has_perm(new_tsec->sid, isec->sid,
2336 SECCLASS_FILE, FILE__ENTRYPOINT, &ad);
2337 if (rc)
2338 return rc;
2339
2340 /* Check for shared state */
2341 if (bprm->unsafe & LSM_UNSAFE_SHARE) {
2342 rc = avc_has_perm(old_tsec->sid, new_tsec->sid,
2343 SECCLASS_PROCESS, PROCESS__SHARE,
2344 NULL);
2345 if (rc)
2346 return -EPERM;
2347 }
2348
2349 /* Make sure that anyone attempting to ptrace over a task that
2350 * changes its SID has the appropriate permit */
2351 if (bprm->unsafe &
2352 (LSM_UNSAFE_PTRACE | LSM_UNSAFE_PTRACE_CAP)) {
2353 struct task_struct *tracer;
2354 struct task_security_struct *sec;
2355 u32 ptsid = 0;
2356
2357 rcu_read_lock();
2358 tracer = ptrace_parent(current);
2359 if (likely(tracer != NULL)) {
2360 sec = __task_cred(tracer)->security;
2361 ptsid = sec->sid;
2362 }
2363 rcu_read_unlock();
2364
2365 if (ptsid != 0) {
2366 rc = avc_has_perm(ptsid, new_tsec->sid,
2367 SECCLASS_PROCESS,
2368 PROCESS__PTRACE, NULL);
2369 if (rc)
2370 return -EPERM;
2371 }
2372 }
2373
2374 /* Clear any possibly unsafe personality bits on exec: */
2375 bprm->per_clear |= PER_CLEAR_ON_SETID;
2376 }
2377
2378 return 0;
2379}
2380
2381static int selinux_bprm_secureexec(struct linux_binprm *bprm)
2382{
2383 const struct task_security_struct *tsec = current_security();
2384 u32 sid, osid;
2385 int atsecure = 0;
2386
2387 sid = tsec->sid;
2388 osid = tsec->osid;
2389
2390 if (osid != sid) {
2391 /* Enable secure mode for SIDs transitions unless
2392 the noatsecure permission is granted between
2393 the two SIDs, i.e. ahp returns 0. */
2394 atsecure = avc_has_perm(osid, sid,
2395 SECCLASS_PROCESS,
2396 PROCESS__NOATSECURE, NULL);
2397 }
2398
2399 return !!atsecure;
2400}
2401
2402static int match_file(const void *p, struct file *file, unsigned fd)
2403{
2404 return file_has_perm(p, file, file_to_av(file)) ? fd + 1 : 0;
2405}
2406
2407/* Derived from fs/exec.c:flush_old_files. */
2408static inline void flush_unauthorized_files(const struct cred *cred,
2409 struct files_struct *files)
2410{
2411 struct file *file, *devnull = NULL;
2412 struct tty_struct *tty;
2413 int drop_tty = 0;
2414 unsigned n;
2415
2416 tty = get_current_tty();
2417 if (tty) {
2418 spin_lock(&tty->files_lock);
2419 if (!list_empty(&tty->tty_files)) {
2420 struct tty_file_private *file_priv;
2421
2422 /* Revalidate access to controlling tty.
2423 Use file_path_has_perm on the tty path directly
2424 rather than using file_has_perm, as this particular
2425 open file may belong to another process and we are
2426 only interested in the inode-based check here. */
2427 file_priv = list_first_entry(&tty->tty_files,
2428 struct tty_file_private, list);
2429 file = file_priv->file;
2430 if (file_path_has_perm(cred, file, FILE__READ | FILE__WRITE))
2431 drop_tty = 1;
2432 }
2433 spin_unlock(&tty->files_lock);
2434 tty_kref_put(tty);
2435 }
2436 /* Reset controlling tty. */
2437 if (drop_tty)
2438 no_tty();
2439
2440 /* Revalidate access to inherited open files. */
2441 n = iterate_fd(files, 0, match_file, cred);
2442 if (!n) /* none found? */
2443 return;
2444
2445 devnull = dentry_open(&selinux_null, O_RDWR, cred);
2446 if (IS_ERR(devnull))
2447 devnull = NULL;
2448 /* replace all the matching ones with this */
2449 do {
2450 replace_fd(n - 1, devnull, 0);
2451 } while ((n = iterate_fd(files, n, match_file, cred)) != 0);
2452 if (devnull)
2453 fput(devnull);
2454}
2455
2456/*
2457 * Prepare a process for imminent new credential changes due to exec
2458 */
2459static void selinux_bprm_committing_creds(struct linux_binprm *bprm)
2460{
2461 struct task_security_struct *new_tsec;
2462 struct rlimit *rlim, *initrlim;
2463 int rc, i;
2464
2465 new_tsec = bprm->cred->security;
2466 if (new_tsec->sid == new_tsec->osid)
2467 return;
2468
2469 /* Close files for which the new task SID is not authorized. */
2470 flush_unauthorized_files(bprm->cred, current->files);
2471
2472 /* Always clear parent death signal on SID transitions. */
2473 current->pdeath_signal = 0;
2474
2475 /* Check whether the new SID can inherit resource limits from the old
2476 * SID. If not, reset all soft limits to the lower of the current
2477 * task's hard limit and the init task's soft limit.
2478 *
2479 * Note that the setting of hard limits (even to lower them) can be
2480 * controlled by the setrlimit check. The inclusion of the init task's
2481 * soft limit into the computation is to avoid resetting soft limits
2482 * higher than the default soft limit for cases where the default is
2483 * lower than the hard limit, e.g. RLIMIT_CORE or RLIMIT_STACK.
2484 */
2485 rc = avc_has_perm(new_tsec->osid, new_tsec->sid, SECCLASS_PROCESS,
2486 PROCESS__RLIMITINH, NULL);
2487 if (rc) {
2488 /* protect against do_prlimit() */
2489 task_lock(current);
2490 for (i = 0; i < RLIM_NLIMITS; i++) {
2491 rlim = current->signal->rlim + i;
2492 initrlim = init_task.signal->rlim + i;
2493 rlim->rlim_cur = min(rlim->rlim_max, initrlim->rlim_cur);
2494 }
2495 task_unlock(current);
2496 update_rlimit_cpu(current, rlimit(RLIMIT_CPU));
2497 }
2498}
2499
2500/*
2501 * Clean up the process immediately after the installation of new credentials
2502 * due to exec
2503 */
2504static void selinux_bprm_committed_creds(struct linux_binprm *bprm)
2505{
2506 const struct task_security_struct *tsec = current_security();
2507 struct itimerval itimer;
2508 u32 osid, sid;
2509 int rc, i;
2510
2511 osid = tsec->osid;
2512 sid = tsec->sid;
2513
2514 if (sid == osid)
2515 return;
2516
2517 /* Check whether the new SID can inherit signal state from the old SID.
2518 * If not, clear itimers to avoid subsequent signal generation and
2519 * flush and unblock signals.
2520 *
2521 * This must occur _after_ the task SID has been updated so that any
2522 * kill done after the flush will be checked against the new SID.
2523 */
2524 rc = avc_has_perm(osid, sid, SECCLASS_PROCESS, PROCESS__SIGINH, NULL);
2525 if (rc) {
2526 memset(&itimer, 0, sizeof itimer);
2527 for (i = 0; i < 3; i++)
2528 do_setitimer(i, &itimer, NULL);
2529 spin_lock_irq(¤t->sighand->siglock);
2530 if (!fatal_signal_pending(current)) {
2531 flush_sigqueue(¤t->pending);
2532 flush_sigqueue(¤t->signal->shared_pending);
2533 flush_signal_handlers(current, 1);
2534 sigemptyset(¤t->blocked);
2535 recalc_sigpending();
2536 }
2537 spin_unlock_irq(¤t->sighand->siglock);
2538 }
2539
2540 /* Wake up the parent if it is waiting so that it can recheck
2541 * wait permission to the new task SID. */
2542 read_lock(&tasklist_lock);
2543 __wake_up_parent(current, current->real_parent);
2544 read_unlock(&tasklist_lock);
2545}
2546
2547/* superblock security operations */
2548
2549static int selinux_sb_alloc_security(struct super_block *sb)
2550{
2551 return superblock_alloc_security(sb);
2552}
2553
2554static void selinux_sb_free_security(struct super_block *sb)
2555{
2556 superblock_free_security(sb);
2557}
2558
2559static inline int match_prefix(char *prefix, int plen, char *option, int olen)
2560{
2561 if (plen > olen)
2562 return 0;
2563
2564 return !memcmp(prefix, option, plen);
2565}
2566
2567static inline int selinux_option(char *option, int len)
2568{
2569 return (match_prefix(CONTEXT_STR, sizeof(CONTEXT_STR)-1, option, len) ||
2570 match_prefix(FSCONTEXT_STR, sizeof(FSCONTEXT_STR)-1, option, len) ||
2571 match_prefix(DEFCONTEXT_STR, sizeof(DEFCONTEXT_STR)-1, option, len) ||
2572 match_prefix(ROOTCONTEXT_STR, sizeof(ROOTCONTEXT_STR)-1, option, len) ||
2573 match_prefix(LABELSUPP_STR, sizeof(LABELSUPP_STR)-1, option, len));
2574}
2575
2576static inline void take_option(char **to, char *from, int *first, int len)
2577{
2578 if (!*first) {
2579 **to = ',';
2580 *to += 1;
2581 } else
2582 *first = 0;
2583 memcpy(*to, from, len);
2584 *to += len;
2585}
2586
2587static inline void take_selinux_option(char **to, char *from, int *first,
2588 int len)
2589{
2590 int current_size = 0;
2591
2592 if (!*first) {
2593 **to = '|';
2594 *to += 1;
2595 } else
2596 *first = 0;
2597
2598 while (current_size < len) {
2599 if (*from != '"') {
2600 **to = *from;
2601 *to += 1;
2602 }
2603 from += 1;
2604 current_size += 1;
2605 }
2606}
2607
2608static int selinux_sb_copy_data(char *orig, char *copy)
2609{
2610 int fnosec, fsec, rc = 0;
2611 char *in_save, *in_curr, *in_end;
2612 char *sec_curr, *nosec_save, *nosec;
2613 int open_quote = 0;
2614
2615 in_curr = orig;
2616 sec_curr = copy;
2617
2618 nosec = (char *)get_zeroed_page(GFP_KERNEL);
2619 if (!nosec) {
2620 rc = -ENOMEM;
2621 goto out;
2622 }
2623
2624 nosec_save = nosec;
2625 fnosec = fsec = 1;
2626 in_save = in_end = orig;
2627
2628 do {
2629 if (*in_end == '"')
2630 open_quote = !open_quote;
2631 if ((*in_end == ',' && open_quote == 0) ||
2632 *in_end == '\0') {
2633 int len = in_end - in_curr;
2634
2635 if (selinux_option(in_curr, len))
2636 take_selinux_option(&sec_curr, in_curr, &fsec, len);
2637 else
2638 take_option(&nosec, in_curr, &fnosec, len);
2639
2640 in_curr = in_end + 1;
2641 }
2642 } while (*in_end++);
2643
2644 strcpy(in_save, nosec_save);
2645 free_page((unsigned long)nosec_save);
2646out:
2647 return rc;
2648}
2649
2650static int selinux_sb_remount(struct super_block *sb, void *data)
2651{
2652 int rc, i, *flags;
2653 struct security_mnt_opts opts;
2654 char *secdata, **mount_options;
2655 struct superblock_security_struct *sbsec = sb->s_security;
2656
2657 if (!(sbsec->flags & SE_SBINITIALIZED))
2658 return 0;
2659
2660 if (!data)
2661 return 0;
2662
2663 if (sb->s_type->fs_flags & FS_BINARY_MOUNTDATA)
2664 return 0;
2665
2666 security_init_mnt_opts(&opts);
2667 secdata = alloc_secdata();
2668 if (!secdata)
2669 return -ENOMEM;
2670 rc = selinux_sb_copy_data(data, secdata);
2671 if (rc)
2672 goto out_free_secdata;
2673
2674 rc = selinux_parse_opts_str(secdata, &opts);
2675 if (rc)
2676 goto out_free_secdata;
2677
2678 mount_options = opts.mnt_opts;
2679 flags = opts.mnt_opts_flags;
2680
2681 for (i = 0; i < opts.num_mnt_opts; i++) {
2682 u32 sid;
2683
2684 if (flags[i] == SBLABEL_MNT)
2685 continue;
2686 rc = security_context_str_to_sid(mount_options[i], &sid, GFP_KERNEL);
2687 if (rc) {
2688 printk(KERN_WARNING "SELinux: security_context_str_to_sid"
2689 "(%s) failed for (dev %s, type %s) errno=%d\n",
2690 mount_options[i], sb->s_id, sb->s_type->name, rc);
2691 goto out_free_opts;
2692 }
2693 rc = -EINVAL;
2694 switch (flags[i]) {
2695 case FSCONTEXT_MNT:
2696 if (bad_option(sbsec, FSCONTEXT_MNT, sbsec->sid, sid))
2697 goto out_bad_option;
2698 break;
2699 case CONTEXT_MNT:
2700 if (bad_option(sbsec, CONTEXT_MNT, sbsec->mntpoint_sid, sid))
2701 goto out_bad_option;
2702 break;
2703 case ROOTCONTEXT_MNT: {
2704 struct inode_security_struct *root_isec;
2705 root_isec = backing_inode_security(sb->s_root);
2706
2707 if (bad_option(sbsec, ROOTCONTEXT_MNT, root_isec->sid, sid))
2708 goto out_bad_option;
2709 break;
2710 }
2711 case DEFCONTEXT_MNT:
2712 if (bad_option(sbsec, DEFCONTEXT_MNT, sbsec->def_sid, sid))
2713 goto out_bad_option;
2714 break;
2715 default:
2716 goto out_free_opts;
2717 }
2718 }
2719
2720 rc = 0;
2721out_free_opts:
2722 security_free_mnt_opts(&opts);
2723out_free_secdata:
2724 free_secdata(secdata);
2725 return rc;
2726out_bad_option:
2727 printk(KERN_WARNING "SELinux: unable to change security options "
2728 "during remount (dev %s, type=%s)\n", sb->s_id,
2729 sb->s_type->name);
2730 goto out_free_opts;
2731}
2732
2733static int selinux_sb_kern_mount(struct super_block *sb, int flags, void *data)
2734{
2735 const struct cred *cred = current_cred();
2736 struct common_audit_data ad;
2737 int rc;
2738
2739 rc = superblock_doinit(sb, data);
2740 if (rc)
2741 return rc;
2742
2743 /* Allow all mounts performed by the kernel */
2744 if (flags & MS_KERNMOUNT)
2745 return 0;
2746
2747 ad.type = LSM_AUDIT_DATA_DENTRY;
2748 ad.u.dentry = sb->s_root;
2749 return superblock_has_perm(cred, sb, FILESYSTEM__MOUNT, &ad);
2750}
2751
2752static int selinux_sb_statfs(struct dentry *dentry)
2753{
2754 const struct cred *cred = current_cred();
2755 struct common_audit_data ad;
2756
2757 ad.type = LSM_AUDIT_DATA_DENTRY;
2758 ad.u.dentry = dentry->d_sb->s_root;
2759 return superblock_has_perm(cred, dentry->d_sb, FILESYSTEM__GETATTR, &ad);
2760}
2761
2762static int selinux_mount(const char *dev_name,
2763 struct path *path,
2764 const char *type,
2765 unsigned long flags,
2766 void *data)
2767{
2768 const struct cred *cred = current_cred();
2769
2770 if (flags & MS_REMOUNT)
2771 return superblock_has_perm(cred, path->dentry->d_sb,
2772 FILESYSTEM__REMOUNT, NULL);
2773 else
2774 return path_has_perm(cred, path, FILE__MOUNTON);
2775}
2776
2777static int selinux_umount(struct vfsmount *mnt, int flags)
2778{
2779 const struct cred *cred = current_cred();
2780
2781 return superblock_has_perm(cred, mnt->mnt_sb,
2782 FILESYSTEM__UNMOUNT, NULL);
2783}
2784
2785/* inode security operations */
2786
2787static int selinux_inode_alloc_security(struct inode *inode)
2788{
2789 return inode_alloc_security(inode);
2790}
2791
2792static void selinux_inode_free_security(struct inode *inode)
2793{
2794 inode_free_security(inode);
2795}
2796
2797static int selinux_dentry_init_security(struct dentry *dentry, int mode,
2798 struct qstr *name, void **ctx,
2799 u32 *ctxlen)
2800{
2801 u32 newsid;
2802 int rc;
2803
2804 rc = selinux_determine_inode_label(d_inode(dentry->d_parent), name,
2805 inode_mode_to_security_class(mode),
2806 &newsid);
2807 if (rc)
2808 return rc;
2809
2810 return security_sid_to_context(newsid, (char **)ctx, ctxlen);
2811}
2812
2813static int selinux_inode_init_security(struct inode *inode, struct inode *dir,
2814 const struct qstr *qstr,
2815 const char **name,
2816 void **value, size_t *len)
2817{
2818 const struct task_security_struct *tsec = current_security();
2819 struct superblock_security_struct *sbsec;
2820 u32 sid, newsid, clen;
2821 int rc;
2822 char *context;
2823
2824 sbsec = dir->i_sb->s_security;
2825
2826 sid = tsec->sid;
2827 newsid = tsec->create_sid;
2828
2829 rc = selinux_determine_inode_label(
2830 dir, qstr,
2831 inode_mode_to_security_class(inode->i_mode),
2832 &newsid);
2833 if (rc)
2834 return rc;
2835
2836 /* Possibly defer initialization to selinux_complete_init. */
2837 if (sbsec->flags & SE_SBINITIALIZED) {
2838 struct inode_security_struct *isec = inode->i_security;
2839 isec->sclass = inode_mode_to_security_class(inode->i_mode);
2840 isec->sid = newsid;
2841 isec->initialized = LABEL_INITIALIZED;
2842 }
2843
2844 if (!ss_initialized || !(sbsec->flags & SBLABEL_MNT))
2845 return -EOPNOTSUPP;
2846
2847 if (name)
2848 *name = XATTR_SELINUX_SUFFIX;
2849
2850 if (value && len) {
2851 rc = security_sid_to_context_force(newsid, &context, &clen);
2852 if (rc)
2853 return rc;
2854 *value = context;
2855 *len = clen;
2856 }
2857
2858 return 0;
2859}
2860
2861static int selinux_inode_create(struct inode *dir, struct dentry *dentry, umode_t mode)
2862{
2863 return may_create(dir, dentry, SECCLASS_FILE);
2864}
2865
2866static int selinux_inode_link(struct dentry *old_dentry, struct inode *dir, struct dentry *new_dentry)
2867{
2868 return may_link(dir, old_dentry, MAY_LINK);
2869}
2870
2871static int selinux_inode_unlink(struct inode *dir, struct dentry *dentry)
2872{
2873 return may_link(dir, dentry, MAY_UNLINK);
2874}
2875
2876static int selinux_inode_symlink(struct inode *dir, struct dentry *dentry, const char *name)
2877{
2878 return may_create(dir, dentry, SECCLASS_LNK_FILE);
2879}
2880
2881static int selinux_inode_mkdir(struct inode *dir, struct dentry *dentry, umode_t mask)
2882{
2883 return may_create(dir, dentry, SECCLASS_DIR);
2884}
2885
2886static int selinux_inode_rmdir(struct inode *dir, struct dentry *dentry)
2887{
2888 return may_link(dir, dentry, MAY_RMDIR);
2889}
2890
2891static int selinux_inode_mknod(struct inode *dir, struct dentry *dentry, umode_t mode, dev_t dev)
2892{
2893 return may_create(dir, dentry, inode_mode_to_security_class(mode));
2894}
2895
2896static int selinux_inode_rename(struct inode *old_inode, struct dentry *old_dentry,
2897 struct inode *new_inode, struct dentry *new_dentry)
2898{
2899 return may_rename(old_inode, old_dentry, new_inode, new_dentry);
2900}
2901
2902static int selinux_inode_readlink(struct dentry *dentry)
2903{
2904 const struct cred *cred = current_cred();
2905
2906 return dentry_has_perm(cred, dentry, FILE__READ);
2907}
2908
2909static int selinux_inode_follow_link(struct dentry *dentry, struct inode *inode,
2910 bool rcu)
2911{
2912 const struct cred *cred = current_cred();
2913 struct common_audit_data ad;
2914 struct inode_security_struct *isec;
2915 u32 sid;
2916
2917 validate_creds(cred);
2918
2919 ad.type = LSM_AUDIT_DATA_DENTRY;
2920 ad.u.dentry = dentry;
2921 sid = cred_sid(cred);
2922 isec = inode_security_rcu(inode, rcu);
2923 if (IS_ERR(isec))
2924 return PTR_ERR(isec);
2925
2926 return avc_has_perm_flags(sid, isec->sid, isec->sclass, FILE__READ, &ad,
2927 rcu ? MAY_NOT_BLOCK : 0);
2928}
2929
2930static noinline int audit_inode_permission(struct inode *inode,
2931 u32 perms, u32 audited, u32 denied,
2932 int result,
2933 unsigned flags)
2934{
2935 struct common_audit_data ad;
2936 struct inode_security_struct *isec = inode->i_security;
2937 int rc;
2938
2939 ad.type = LSM_AUDIT_DATA_INODE;
2940 ad.u.inode = inode;
2941
2942 rc = slow_avc_audit(current_sid(), isec->sid, isec->sclass, perms,
2943 audited, denied, result, &ad, flags);
2944 if (rc)
2945 return rc;
2946 return 0;
2947}
2948
2949static int selinux_inode_permission(struct inode *inode, int mask)
2950{
2951 const struct cred *cred = current_cred();
2952 u32 perms;
2953 bool from_access;
2954 unsigned flags = mask & MAY_NOT_BLOCK;
2955 struct inode_security_struct *isec;
2956 u32 sid;
2957 struct av_decision avd;
2958 int rc, rc2;
2959 u32 audited, denied;
2960
2961 from_access = mask & MAY_ACCESS;
2962 mask &= (MAY_READ|MAY_WRITE|MAY_EXEC|MAY_APPEND);
2963
2964 /* No permission to check. Existence test. */
2965 if (!mask)
2966 return 0;
2967
2968 validate_creds(cred);
2969
2970 if (unlikely(IS_PRIVATE(inode)))
2971 return 0;
2972
2973 perms = file_mask_to_av(inode->i_mode, mask);
2974
2975 sid = cred_sid(cred);
2976 isec = inode_security_rcu(inode, flags & MAY_NOT_BLOCK);
2977 if (IS_ERR(isec))
2978 return PTR_ERR(isec);
2979
2980 rc = avc_has_perm_noaudit(sid, isec->sid, isec->sclass, perms, 0, &avd);
2981 audited = avc_audit_required(perms, &avd, rc,
2982 from_access ? FILE__AUDIT_ACCESS : 0,
2983 &denied);
2984 if (likely(!audited))
2985 return rc;
2986
2987 rc2 = audit_inode_permission(inode, perms, audited, denied, rc, flags);
2988 if (rc2)
2989 return rc2;
2990 return rc;
2991}
2992
2993static int selinux_inode_setattr(struct dentry *dentry, struct iattr *iattr)
2994{
2995 const struct cred *cred = current_cred();
2996 unsigned int ia_valid = iattr->ia_valid;
2997 __u32 av = FILE__WRITE;
2998
2999 /* ATTR_FORCE is just used for ATTR_KILL_S[UG]ID. */
3000 if (ia_valid & ATTR_FORCE) {
3001 ia_valid &= ~(ATTR_KILL_SUID | ATTR_KILL_SGID | ATTR_MODE |
3002 ATTR_FORCE);
3003 if (!ia_valid)
3004 return 0;
3005 }
3006
3007 if (ia_valid & (ATTR_MODE | ATTR_UID | ATTR_GID |
3008 ATTR_ATIME_SET | ATTR_MTIME_SET | ATTR_TIMES_SET))
3009 return dentry_has_perm(cred, dentry, FILE__SETATTR);
3010
3011 if (selinux_policycap_openperm && (ia_valid & ATTR_SIZE)
3012 && !(ia_valid & ATTR_FILE))
3013 av |= FILE__OPEN;
3014
3015 return dentry_has_perm(cred, dentry, av);
3016}
3017
3018static int selinux_inode_getattr(const struct path *path)
3019{
3020 return path_has_perm(current_cred(), path, FILE__GETATTR);
3021}
3022
3023static int selinux_inode_setotherxattr(struct dentry *dentry, const char *name)
3024{
3025 const struct cred *cred = current_cred();
3026
3027 if (!strncmp(name, XATTR_SECURITY_PREFIX,
3028 sizeof XATTR_SECURITY_PREFIX - 1)) {
3029 if (!strcmp(name, XATTR_NAME_CAPS)) {
3030 if (!capable(CAP_SETFCAP))
3031 return -EPERM;
3032 } else if (!capable(CAP_SYS_ADMIN)) {
3033 /* A different attribute in the security namespace.
3034 Restrict to administrator. */
3035 return -EPERM;
3036 }
3037 }
3038
3039 /* Not an attribute we recognize, so just check the
3040 ordinary setattr permission. */
3041 return dentry_has_perm(cred, dentry, FILE__SETATTR);
3042}
3043
3044static int selinux_inode_setxattr(struct dentry *dentry, const char *name,
3045 const void *value, size_t size, int flags)
3046{
3047 struct inode *inode = d_backing_inode(dentry);
3048 struct inode_security_struct *isec = backing_inode_security(dentry);
3049 struct superblock_security_struct *sbsec;
3050 struct common_audit_data ad;
3051 u32 newsid, sid = current_sid();
3052 int rc = 0;
3053
3054 if (strcmp(name, XATTR_NAME_SELINUX))
3055 return selinux_inode_setotherxattr(dentry, name);
3056
3057 sbsec = inode->i_sb->s_security;
3058 if (!(sbsec->flags & SBLABEL_MNT))
3059 return -EOPNOTSUPP;
3060
3061 if (!inode_owner_or_capable(inode))
3062 return -EPERM;
3063
3064 ad.type = LSM_AUDIT_DATA_DENTRY;
3065 ad.u.dentry = dentry;
3066
3067 rc = avc_has_perm(sid, isec->sid, isec->sclass,
3068 FILE__RELABELFROM, &ad);
3069 if (rc)
3070 return rc;
3071
3072 rc = security_context_to_sid(value, size, &newsid, GFP_KERNEL);
3073 if (rc == -EINVAL) {
3074 if (!capable(CAP_MAC_ADMIN)) {
3075 struct audit_buffer *ab;
3076 size_t audit_size;
3077 const char *str;
3078
3079 /* We strip a nul only if it is at the end, otherwise the
3080 * context contains a nul and we should audit that */
3081 if (value) {
3082 str = value;
3083 if (str[size - 1] == '\0')
3084 audit_size = size - 1;
3085 else
3086 audit_size = size;
3087 } else {
3088 str = "";
3089 audit_size = 0;
3090 }
3091 ab = audit_log_start(current->audit_context, GFP_ATOMIC, AUDIT_SELINUX_ERR);
3092 audit_log_format(ab, "op=setxattr invalid_context=");
3093 audit_log_n_untrustedstring(ab, value, audit_size);
3094 audit_log_end(ab);
3095
3096 return rc;
3097 }
3098 rc = security_context_to_sid_force(value, size, &newsid);
3099 }
3100 if (rc)
3101 return rc;
3102
3103 rc = avc_has_perm(sid, newsid, isec->sclass,
3104 FILE__RELABELTO, &ad);
3105 if (rc)
3106 return rc;
3107
3108 rc = security_validate_transition(isec->sid, newsid, sid,
3109 isec->sclass);
3110 if (rc)
3111 return rc;
3112
3113 return avc_has_perm(newsid,
3114 sbsec->sid,
3115 SECCLASS_FILESYSTEM,
3116 FILESYSTEM__ASSOCIATE,
3117 &ad);
3118}
3119
3120static void selinux_inode_post_setxattr(struct dentry *dentry, const char *name,
3121 const void *value, size_t size,
3122 int flags)
3123{
3124 struct inode *inode = d_backing_inode(dentry);
3125 struct inode_security_struct *isec = backing_inode_security(dentry);
3126 u32 newsid;
3127 int rc;
3128
3129 if (strcmp(name, XATTR_NAME_SELINUX)) {
3130 /* Not an attribute we recognize, so nothing to do. */
3131 return;
3132 }
3133
3134 rc = security_context_to_sid_force(value, size, &newsid);
3135 if (rc) {
3136 printk(KERN_ERR "SELinux: unable to map context to SID"
3137 "for (%s, %lu), rc=%d\n",
3138 inode->i_sb->s_id, inode->i_ino, -rc);
3139 return;
3140 }
3141
3142 isec->sclass = inode_mode_to_security_class(inode->i_mode);
3143 isec->sid = newsid;
3144 isec->initialized = LABEL_INITIALIZED;
3145
3146 return;
3147}
3148
3149static int selinux_inode_getxattr(struct dentry *dentry, const char *name)
3150{
3151 const struct cred *cred = current_cred();
3152
3153 return dentry_has_perm(cred, dentry, FILE__GETATTR);
3154}
3155
3156static int selinux_inode_listxattr(struct dentry *dentry)
3157{
3158 const struct cred *cred = current_cred();
3159
3160 return dentry_has_perm(cred, dentry, FILE__GETATTR);
3161}
3162
3163static int selinux_inode_removexattr(struct dentry *dentry, const char *name)
3164{
3165 if (strcmp(name, XATTR_NAME_SELINUX))
3166 return selinux_inode_setotherxattr(dentry, name);
3167
3168 /* No one is allowed to remove a SELinux security label.
3169 You can change the label, but all data must be labeled. */
3170 return -EACCES;
3171}
3172
3173/*
3174 * Copy the inode security context value to the user.
3175 *
3176 * Permission check is handled by selinux_inode_getxattr hook.
3177 */
3178static int selinux_inode_getsecurity(struct inode *inode, const char *name, void **buffer, bool alloc)
3179{
3180 u32 size;
3181 int error;
3182 char *context = NULL;
3183 struct inode_security_struct *isec = inode_security(inode);
3184
3185 if (strcmp(name, XATTR_SELINUX_SUFFIX))
3186 return -EOPNOTSUPP;
3187
3188 /*
3189 * If the caller has CAP_MAC_ADMIN, then get the raw context
3190 * value even if it is not defined by current policy; otherwise,
3191 * use the in-core value under current policy.
3192 * Use the non-auditing forms of the permission checks since
3193 * getxattr may be called by unprivileged processes commonly
3194 * and lack of permission just means that we fall back to the
3195 * in-core context value, not a denial.
3196 */
3197 error = cap_capable(current_cred(), &init_user_ns, CAP_MAC_ADMIN,
3198 SECURITY_CAP_NOAUDIT);
3199 if (!error)
3200 error = cred_has_capability(current_cred(), CAP_MAC_ADMIN,
3201 SECURITY_CAP_NOAUDIT);
3202 if (!error)
3203 error = security_sid_to_context_force(isec->sid, &context,
3204 &size);
3205 else
3206 error = security_sid_to_context(isec->sid, &context, &size);
3207 if (error)
3208 return error;
3209 error = size;
3210 if (alloc) {
3211 *buffer = context;
3212 goto out_nofree;
3213 }
3214 kfree(context);
3215out_nofree:
3216 return error;
3217}
3218
3219static int selinux_inode_setsecurity(struct inode *inode, const char *name,
3220 const void *value, size_t size, int flags)
3221{
3222 struct inode_security_struct *isec = inode_security(inode);
3223 u32 newsid;
3224 int rc;
3225
3226 if (strcmp(name, XATTR_SELINUX_SUFFIX))
3227 return -EOPNOTSUPP;
3228
3229 if (!value || !size)
3230 return -EACCES;
3231
3232 rc = security_context_to_sid(value, size, &newsid, GFP_KERNEL);
3233 if (rc)
3234 return rc;
3235
3236 isec->sclass = inode_mode_to_security_class(inode->i_mode);
3237 isec->sid = newsid;
3238 isec->initialized = LABEL_INITIALIZED;
3239 return 0;
3240}
3241
3242static int selinux_inode_listsecurity(struct inode *inode, char *buffer, size_t buffer_size)
3243{
3244 const int len = sizeof(XATTR_NAME_SELINUX);
3245 if (buffer && len <= buffer_size)
3246 memcpy(buffer, XATTR_NAME_SELINUX, len);
3247 return len;
3248}
3249
3250static void selinux_inode_getsecid(struct inode *inode, u32 *secid)
3251{
3252 struct inode_security_struct *isec = inode_security_novalidate(inode);
3253 *secid = isec->sid;
3254}
3255
3256/* file security operations */
3257
3258static int selinux_revalidate_file_permission(struct file *file, int mask)
3259{
3260 const struct cred *cred = current_cred();
3261 struct inode *inode = file_inode(file);
3262
3263 /* file_mask_to_av won't add FILE__WRITE if MAY_APPEND is set */
3264 if ((file->f_flags & O_APPEND) && (mask & MAY_WRITE))
3265 mask |= MAY_APPEND;
3266
3267 return file_has_perm(cred, file,
3268 file_mask_to_av(inode->i_mode, mask));
3269}
3270
3271static int selinux_file_permission(struct file *file, int mask)
3272{
3273 struct inode *inode = file_inode(file);
3274 struct file_security_struct *fsec = file->f_security;
3275 struct inode_security_struct *isec;
3276 u32 sid = current_sid();
3277
3278 if (!mask)
3279 /* No permission to check. Existence test. */
3280 return 0;
3281
3282 isec = inode_security(inode);
3283 if (sid == fsec->sid && fsec->isid == isec->sid &&
3284 fsec->pseqno == avc_policy_seqno())
3285 /* No change since file_open check. */
3286 return 0;
3287
3288 return selinux_revalidate_file_permission(file, mask);
3289}
3290
3291static int selinux_file_alloc_security(struct file *file)
3292{
3293 return file_alloc_security(file);
3294}
3295
3296static void selinux_file_free_security(struct file *file)
3297{
3298 file_free_security(file);
3299}
3300
3301/*
3302 * Check whether a task has the ioctl permission and cmd
3303 * operation to an inode.
3304 */
3305static int ioctl_has_perm(const struct cred *cred, struct file *file,
3306 u32 requested, u16 cmd)
3307{
3308 struct common_audit_data ad;
3309 struct file_security_struct *fsec = file->f_security;
3310 struct inode *inode = file_inode(file);
3311 struct inode_security_struct *isec = inode_security(inode);
3312 struct lsm_ioctlop_audit ioctl;
3313 u32 ssid = cred_sid(cred);
3314 int rc;
3315 u8 driver = cmd >> 8;
3316 u8 xperm = cmd & 0xff;
3317
3318 ad.type = LSM_AUDIT_DATA_IOCTL_OP;
3319 ad.u.op = &ioctl;
3320 ad.u.op->cmd = cmd;
3321 ad.u.op->path = file->f_path;
3322
3323 if (ssid != fsec->sid) {
3324 rc = avc_has_perm(ssid, fsec->sid,
3325 SECCLASS_FD,
3326 FD__USE,
3327 &ad);
3328 if (rc)
3329 goto out;
3330 }
3331
3332 if (unlikely(IS_PRIVATE(inode)))
3333 return 0;
3334
3335 rc = avc_has_extended_perms(ssid, isec->sid, isec->sclass,
3336 requested, driver, xperm, &ad);
3337out:
3338 return rc;
3339}
3340
3341static int selinux_file_ioctl(struct file *file, unsigned int cmd,
3342 unsigned long arg)
3343{
3344 const struct cred *cred = current_cred();
3345 int error = 0;
3346
3347 switch (cmd) {
3348 case FIONREAD:
3349 /* fall through */
3350 case FIBMAP:
3351 /* fall through */
3352 case FIGETBSZ:
3353 /* fall through */
3354 case FS_IOC_GETFLAGS:
3355 /* fall through */
3356 case FS_IOC_GETVERSION:
3357 error = file_has_perm(cred, file, FILE__GETATTR);
3358 break;
3359
3360 case FS_IOC_SETFLAGS:
3361 /* fall through */
3362 case FS_IOC_SETVERSION:
3363 error = file_has_perm(cred, file, FILE__SETATTR);
3364 break;
3365
3366 /* sys_ioctl() checks */
3367 case FIONBIO:
3368 /* fall through */
3369 case FIOASYNC:
3370 error = file_has_perm(cred, file, 0);
3371 break;
3372
3373 case KDSKBENT:
3374 case KDSKBSENT:
3375 error = cred_has_capability(cred, CAP_SYS_TTY_CONFIG,
3376 SECURITY_CAP_AUDIT);
3377 break;
3378
3379 /* default case assumes that the command will go
3380 * to the file's ioctl() function.
3381 */
3382 default:
3383 error = ioctl_has_perm(cred, file, FILE__IOCTL, (u16) cmd);
3384 }
3385 return error;
3386}
3387
3388static int default_noexec;
3389
3390static int file_map_prot_check(struct file *file, unsigned long prot, int shared)
3391{
3392 const struct cred *cred = current_cred();
3393 int rc = 0;
3394
3395 if (default_noexec &&
3396 (prot & PROT_EXEC) && (!file || IS_PRIVATE(file_inode(file)) ||
3397 (!shared && (prot & PROT_WRITE)))) {
3398 /*
3399 * We are making executable an anonymous mapping or a
3400 * private file mapping that will also be writable.
3401 * This has an additional check.
3402 */
3403 rc = cred_has_perm(cred, cred, PROCESS__EXECMEM);
3404 if (rc)
3405 goto error;
3406 }
3407
3408 if (file) {
3409 /* read access is always possible with a mapping */
3410 u32 av = FILE__READ;
3411
3412 /* write access only matters if the mapping is shared */
3413 if (shared && (prot & PROT_WRITE))
3414 av |= FILE__WRITE;
3415
3416 if (prot & PROT_EXEC)
3417 av |= FILE__EXECUTE;
3418
3419 return file_has_perm(cred, file, av);
3420 }
3421
3422error:
3423 return rc;
3424}
3425
3426static int selinux_mmap_addr(unsigned long addr)
3427{
3428 int rc = 0;
3429
3430 if (addr < CONFIG_LSM_MMAP_MIN_ADDR) {
3431 u32 sid = current_sid();
3432 rc = avc_has_perm(sid, sid, SECCLASS_MEMPROTECT,
3433 MEMPROTECT__MMAP_ZERO, NULL);
3434 }
3435
3436 return rc;
3437}
3438
3439static int selinux_mmap_file(struct file *file, unsigned long reqprot,
3440 unsigned long prot, unsigned long flags)
3441{
3442 if (selinux_checkreqprot)
3443 prot = reqprot;
3444
3445 return file_map_prot_check(file, prot,
3446 (flags & MAP_TYPE) == MAP_SHARED);
3447}
3448
3449static int selinux_file_mprotect(struct vm_area_struct *vma,
3450 unsigned long reqprot,
3451 unsigned long prot)
3452{
3453 const struct cred *cred = current_cred();
3454
3455 if (selinux_checkreqprot)
3456 prot = reqprot;
3457
3458 if (default_noexec &&
3459 (prot & PROT_EXEC) && !(vma->vm_flags & VM_EXEC)) {
3460 int rc = 0;
3461 if (vma->vm_start >= vma->vm_mm->start_brk &&
3462 vma->vm_end <= vma->vm_mm->brk) {
3463 rc = cred_has_perm(cred, cred, PROCESS__EXECHEAP);
3464 } else if (!vma->vm_file &&
3465 vma->vm_start <= vma->vm_mm->start_stack &&
3466 vma->vm_end >= vma->vm_mm->start_stack) {
3467 rc = current_has_perm(current, PROCESS__EXECSTACK);
3468 } else if (vma->vm_file && vma->anon_vma) {
3469 /*
3470 * We are making executable a file mapping that has
3471 * had some COW done. Since pages might have been
3472 * written, check ability to execute the possibly
3473 * modified content. This typically should only
3474 * occur for text relocations.
3475 */
3476 rc = file_has_perm(cred, vma->vm_file, FILE__EXECMOD);
3477 }
3478 if (rc)
3479 return rc;
3480 }
3481
3482 return file_map_prot_check(vma->vm_file, prot, vma->vm_flags&VM_SHARED);
3483}
3484
3485static int selinux_file_lock(struct file *file, unsigned int cmd)
3486{
3487 const struct cred *cred = current_cred();
3488
3489 return file_has_perm(cred, file, FILE__LOCK);
3490}
3491
3492static int selinux_file_fcntl(struct file *file, unsigned int cmd,
3493 unsigned long arg)
3494{
3495 const struct cred *cred = current_cred();
3496 int err = 0;
3497
3498 switch (cmd) {
3499 case F_SETFL:
3500 if ((file->f_flags & O_APPEND) && !(arg & O_APPEND)) {
3501 err = file_has_perm(cred, file, FILE__WRITE);
3502 break;
3503 }
3504 /* fall through */
3505 case F_SETOWN:
3506 case F_SETSIG:
3507 case F_GETFL:
3508 case F_GETOWN:
3509 case F_GETSIG:
3510 case F_GETOWNER_UIDS:
3511 /* Just check FD__USE permission */
3512 err = file_has_perm(cred, file, 0);
3513 break;
3514 case F_GETLK:
3515 case F_SETLK:
3516 case F_SETLKW:
3517 case F_OFD_GETLK:
3518 case F_OFD_SETLK:
3519 case F_OFD_SETLKW:
3520#if BITS_PER_LONG == 32
3521 case F_GETLK64:
3522 case F_SETLK64:
3523 case F_SETLKW64:
3524#endif
3525 err = file_has_perm(cred, file, FILE__LOCK);
3526 break;
3527 }
3528
3529 return err;
3530}
3531
3532static void selinux_file_set_fowner(struct file *file)
3533{
3534 struct file_security_struct *fsec;
3535
3536 fsec = file->f_security;
3537 fsec->fown_sid = current_sid();
3538}
3539
3540static int selinux_file_send_sigiotask(struct task_struct *tsk,
3541 struct fown_struct *fown, int signum)
3542{
3543 struct file *file;
3544 u32 sid = task_sid(tsk);
3545 u32 perm;
3546 struct file_security_struct *fsec;
3547
3548 /* struct fown_struct is never outside the context of a struct file */
3549 file = container_of(fown, struct file, f_owner);
3550
3551 fsec = file->f_security;
3552
3553 if (!signum)
3554 perm = signal_to_av(SIGIO); /* as per send_sigio_to_task */
3555 else
3556 perm = signal_to_av(signum);
3557
3558 return avc_has_perm(fsec->fown_sid, sid,
3559 SECCLASS_PROCESS, perm, NULL);
3560}
3561
3562static int selinux_file_receive(struct file *file)
3563{
3564 const struct cred *cred = current_cred();
3565
3566 return file_has_perm(cred, file, file_to_av(file));
3567}
3568
3569static int selinux_file_open(struct file *file, const struct cred *cred)
3570{
3571 struct file_security_struct *fsec;
3572 struct inode_security_struct *isec;
3573
3574 fsec = file->f_security;
3575 isec = inode_security(file_inode(file));
3576 /*
3577 * Save inode label and policy sequence number
3578 * at open-time so that selinux_file_permission
3579 * can determine whether revalidation is necessary.
3580 * Task label is already saved in the file security
3581 * struct as its SID.
3582 */
3583 fsec->isid = isec->sid;
3584 fsec->pseqno = avc_policy_seqno();
3585 /*
3586 * Since the inode label or policy seqno may have changed
3587 * between the selinux_inode_permission check and the saving
3588 * of state above, recheck that access is still permitted.
3589 * Otherwise, access might never be revalidated against the
3590 * new inode label or new policy.
3591 * This check is not redundant - do not remove.
3592 */
3593 return file_path_has_perm(cred, file, open_file_to_av(file));
3594}
3595
3596/* task security operations */
3597
3598static int selinux_task_create(unsigned long clone_flags)
3599{
3600 return current_has_perm(current, PROCESS__FORK);
3601}
3602
3603/*
3604 * allocate the SELinux part of blank credentials
3605 */
3606static int selinux_cred_alloc_blank(struct cred *cred, gfp_t gfp)
3607{
3608 struct task_security_struct *tsec;
3609
3610 tsec = kzalloc(sizeof(struct task_security_struct), gfp);
3611 if (!tsec)
3612 return -ENOMEM;
3613
3614 cred->security = tsec;
3615 return 0;
3616}
3617
3618/*
3619 * detach and free the LSM part of a set of credentials
3620 */
3621static void selinux_cred_free(struct cred *cred)
3622{
3623 struct task_security_struct *tsec = cred->security;
3624
3625 /*
3626 * cred->security == NULL if security_cred_alloc_blank() or
3627 * security_prepare_creds() returned an error.
3628 */
3629 BUG_ON(cred->security && (unsigned long) cred->security < PAGE_SIZE);
3630 cred->security = (void *) 0x7UL;
3631 kfree(tsec);
3632}
3633
3634/*
3635 * prepare a new set of credentials for modification
3636 */
3637static int selinux_cred_prepare(struct cred *new, const struct cred *old,
3638 gfp_t gfp)
3639{
3640 const struct task_security_struct *old_tsec;
3641 struct task_security_struct *tsec;
3642
3643 old_tsec = old->security;
3644
3645 tsec = kmemdup(old_tsec, sizeof(struct task_security_struct), gfp);
3646 if (!tsec)
3647 return -ENOMEM;
3648
3649 new->security = tsec;
3650 return 0;
3651}
3652
3653/*
3654 * transfer the SELinux data to a blank set of creds
3655 */
3656static void selinux_cred_transfer(struct cred *new, const struct cred *old)
3657{
3658 const struct task_security_struct *old_tsec = old->security;
3659 struct task_security_struct *tsec = new->security;
3660
3661 *tsec = *old_tsec;
3662}
3663
3664/*
3665 * set the security data for a kernel service
3666 * - all the creation contexts are set to unlabelled
3667 */
3668static int selinux_kernel_act_as(struct cred *new, u32 secid)
3669{
3670 struct task_security_struct *tsec = new->security;
3671 u32 sid = current_sid();
3672 int ret;
3673
3674 ret = avc_has_perm(sid, secid,
3675 SECCLASS_KERNEL_SERVICE,
3676 KERNEL_SERVICE__USE_AS_OVERRIDE,
3677 NULL);
3678 if (ret == 0) {
3679 tsec->sid = secid;
3680 tsec->create_sid = 0;
3681 tsec->keycreate_sid = 0;
3682 tsec->sockcreate_sid = 0;
3683 }
3684 return ret;
3685}
3686
3687/*
3688 * set the file creation context in a security record to the same as the
3689 * objective context of the specified inode
3690 */
3691static int selinux_kernel_create_files_as(struct cred *new, struct inode *inode)
3692{
3693 struct inode_security_struct *isec = inode_security(inode);
3694 struct task_security_struct *tsec = new->security;
3695 u32 sid = current_sid();
3696 int ret;
3697
3698 ret = avc_has_perm(sid, isec->sid,
3699 SECCLASS_KERNEL_SERVICE,
3700 KERNEL_SERVICE__CREATE_FILES_AS,
3701 NULL);
3702
3703 if (ret == 0)
3704 tsec->create_sid = isec->sid;
3705 return ret;
3706}
3707
3708static int selinux_kernel_module_request(char *kmod_name)
3709{
3710 u32 sid;
3711 struct common_audit_data ad;
3712
3713 sid = task_sid(current);
3714
3715 ad.type = LSM_AUDIT_DATA_KMOD;
3716 ad.u.kmod_name = kmod_name;
3717
3718 return avc_has_perm(sid, SECINITSID_KERNEL, SECCLASS_SYSTEM,
3719 SYSTEM__MODULE_REQUEST, &ad);
3720}
3721
3722static int selinux_task_setpgid(struct task_struct *p, pid_t pgid)
3723{
3724 return current_has_perm(p, PROCESS__SETPGID);
3725}
3726
3727static int selinux_task_getpgid(struct task_struct *p)
3728{
3729 return current_has_perm(p, PROCESS__GETPGID);
3730}
3731
3732static int selinux_task_getsid(struct task_struct *p)
3733{
3734 return current_has_perm(p, PROCESS__GETSESSION);
3735}
3736
3737static void selinux_task_getsecid(struct task_struct *p, u32 *secid)
3738{
3739 *secid = task_sid(p);
3740}
3741
3742static int selinux_task_setnice(struct task_struct *p, int nice)
3743{
3744 return current_has_perm(p, PROCESS__SETSCHED);
3745}
3746
3747static int selinux_task_setioprio(struct task_struct *p, int ioprio)
3748{
3749 return current_has_perm(p, PROCESS__SETSCHED);
3750}
3751
3752static int selinux_task_getioprio(struct task_struct *p)
3753{
3754 return current_has_perm(p, PROCESS__GETSCHED);
3755}
3756
3757static int selinux_task_setrlimit(struct task_struct *p, unsigned int resource,
3758 struct rlimit *new_rlim)
3759{
3760 struct rlimit *old_rlim = p->signal->rlim + resource;
3761
3762 /* Control the ability to change the hard limit (whether
3763 lowering or raising it), so that the hard limit can
3764 later be used as a safe reset point for the soft limit
3765 upon context transitions. See selinux_bprm_committing_creds. */
3766 if (old_rlim->rlim_max != new_rlim->rlim_max)
3767 return current_has_perm(p, PROCESS__SETRLIMIT);
3768
3769 return 0;
3770}
3771
3772static int selinux_task_setscheduler(struct task_struct *p)
3773{
3774 return current_has_perm(p, PROCESS__SETSCHED);
3775}
3776
3777static int selinux_task_getscheduler(struct task_struct *p)
3778{
3779 return current_has_perm(p, PROCESS__GETSCHED);
3780}
3781
3782static int selinux_task_movememory(struct task_struct *p)
3783{
3784 return current_has_perm(p, PROCESS__SETSCHED);
3785}
3786
3787static int selinux_task_kill(struct task_struct *p, struct siginfo *info,
3788 int sig, u32 secid)
3789{
3790 u32 perm;
3791 int rc;
3792
3793 if (!sig)
3794 perm = PROCESS__SIGNULL; /* null signal; existence test */
3795 else
3796 perm = signal_to_av(sig);
3797 if (secid)
3798 rc = avc_has_perm(secid, task_sid(p),
3799 SECCLASS_PROCESS, perm, NULL);
3800 else
3801 rc = current_has_perm(p, perm);
3802 return rc;
3803}
3804
3805static int selinux_task_wait(struct task_struct *p)
3806{
3807 return task_has_perm(p, current, PROCESS__SIGCHLD);
3808}
3809
3810static void selinux_task_to_inode(struct task_struct *p,
3811 struct inode *inode)
3812{
3813 struct inode_security_struct *isec = inode->i_security;
3814 u32 sid = task_sid(p);
3815
3816 isec->sid = sid;
3817 isec->initialized = LABEL_INITIALIZED;
3818}
3819
3820/* Returns error only if unable to parse addresses */
3821static int selinux_parse_skb_ipv4(struct sk_buff *skb,
3822 struct common_audit_data *ad, u8 *proto)
3823{
3824 int offset, ihlen, ret = -EINVAL;
3825 struct iphdr _iph, *ih;
3826
3827 offset = skb_network_offset(skb);
3828 ih = skb_header_pointer(skb, offset, sizeof(_iph), &_iph);
3829 if (ih == NULL)
3830 goto out;
3831
3832 ihlen = ih->ihl * 4;
3833 if (ihlen < sizeof(_iph))
3834 goto out;
3835
3836 ad->u.net->v4info.saddr = ih->saddr;
3837 ad->u.net->v4info.daddr = ih->daddr;
3838 ret = 0;
3839
3840 if (proto)
3841 *proto = ih->protocol;
3842
3843 switch (ih->protocol) {
3844 case IPPROTO_TCP: {
3845 struct tcphdr _tcph, *th;
3846
3847 if (ntohs(ih->frag_off) & IP_OFFSET)
3848 break;
3849
3850 offset += ihlen;
3851 th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph);
3852 if (th == NULL)
3853 break;
3854
3855 ad->u.net->sport = th->source;
3856 ad->u.net->dport = th->dest;
3857 break;
3858 }
3859
3860 case IPPROTO_UDP: {
3861 struct udphdr _udph, *uh;
3862
3863 if (ntohs(ih->frag_off) & IP_OFFSET)
3864 break;
3865
3866 offset += ihlen;
3867 uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph);
3868 if (uh == NULL)
3869 break;
3870
3871 ad->u.net->sport = uh->source;
3872 ad->u.net->dport = uh->dest;
3873 break;
3874 }
3875
3876 case IPPROTO_DCCP: {
3877 struct dccp_hdr _dccph, *dh;
3878
3879 if (ntohs(ih->frag_off) & IP_OFFSET)
3880 break;
3881
3882 offset += ihlen;
3883 dh = skb_header_pointer(skb, offset, sizeof(_dccph), &_dccph);
3884 if (dh == NULL)
3885 break;
3886
3887 ad->u.net->sport = dh->dccph_sport;
3888 ad->u.net->dport = dh->dccph_dport;
3889 break;
3890 }
3891
3892 default:
3893 break;
3894 }
3895out:
3896 return ret;
3897}
3898
3899#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
3900
3901/* Returns error only if unable to parse addresses */
3902static int selinux_parse_skb_ipv6(struct sk_buff *skb,
3903 struct common_audit_data *ad, u8 *proto)
3904{
3905 u8 nexthdr;
3906 int ret = -EINVAL, offset;
3907 struct ipv6hdr _ipv6h, *ip6;
3908 __be16 frag_off;
3909
3910 offset = skb_network_offset(skb);
3911 ip6 = skb_header_pointer(skb, offset, sizeof(_ipv6h), &_ipv6h);
3912 if (ip6 == NULL)
3913 goto out;
3914
3915 ad->u.net->v6info.saddr = ip6->saddr;
3916 ad->u.net->v6info.daddr = ip6->daddr;
3917 ret = 0;
3918
3919 nexthdr = ip6->nexthdr;
3920 offset += sizeof(_ipv6h);
3921 offset = ipv6_skip_exthdr(skb, offset, &nexthdr, &frag_off);
3922 if (offset < 0)
3923 goto out;
3924
3925 if (proto)
3926 *proto = nexthdr;
3927
3928 switch (nexthdr) {
3929 case IPPROTO_TCP: {
3930 struct tcphdr _tcph, *th;
3931
3932 th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph);
3933 if (th == NULL)
3934 break;
3935
3936 ad->u.net->sport = th->source;
3937 ad->u.net->dport = th->dest;
3938 break;
3939 }
3940
3941 case IPPROTO_UDP: {
3942 struct udphdr _udph, *uh;
3943
3944 uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph);
3945 if (uh == NULL)
3946 break;
3947
3948 ad->u.net->sport = uh->source;
3949 ad->u.net->dport = uh->dest;
3950 break;
3951 }
3952
3953 case IPPROTO_DCCP: {
3954 struct dccp_hdr _dccph, *dh;
3955
3956 dh = skb_header_pointer(skb, offset, sizeof(_dccph), &_dccph);
3957 if (dh == NULL)
3958 break;
3959
3960 ad->u.net->sport = dh->dccph_sport;
3961 ad->u.net->dport = dh->dccph_dport;
3962 break;
3963 }
3964
3965 /* includes fragments */
3966 default:
3967 break;
3968 }
3969out:
3970 return ret;
3971}
3972
3973#endif /* IPV6 */
3974
3975static int selinux_parse_skb(struct sk_buff *skb, struct common_audit_data *ad,
3976 char **_addrp, int src, u8 *proto)
3977{
3978 char *addrp;
3979 int ret;
3980
3981 switch (ad->u.net->family) {
3982 case PF_INET:
3983 ret = selinux_parse_skb_ipv4(skb, ad, proto);
3984 if (ret)
3985 goto parse_error;
3986 addrp = (char *)(src ? &ad->u.net->v4info.saddr :
3987 &ad->u.net->v4info.daddr);
3988 goto okay;
3989
3990#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
3991 case PF_INET6:
3992 ret = selinux_parse_skb_ipv6(skb, ad, proto);
3993 if (ret)
3994 goto parse_error;
3995 addrp = (char *)(src ? &ad->u.net->v6info.saddr :
3996 &ad->u.net->v6info.daddr);
3997 goto okay;
3998#endif /* IPV6 */
3999 default:
4000 addrp = NULL;
4001 goto okay;
4002 }
4003
4004parse_error:
4005 printk(KERN_WARNING
4006 "SELinux: failure in selinux_parse_skb(),"
4007 " unable to parse packet\n");
4008 return ret;
4009
4010okay:
4011 if (_addrp)
4012 *_addrp = addrp;
4013 return 0;
4014}
4015
4016/**
4017 * selinux_skb_peerlbl_sid - Determine the peer label of a packet
4018 * @skb: the packet
4019 * @family: protocol family
4020 * @sid: the packet's peer label SID
4021 *
4022 * Description:
4023 * Check the various different forms of network peer labeling and determine
4024 * the peer label/SID for the packet; most of the magic actually occurs in
4025 * the security server function security_net_peersid_cmp(). The function
4026 * returns zero if the value in @sid is valid (although it may be SECSID_NULL)
4027 * or -EACCES if @sid is invalid due to inconsistencies with the different
4028 * peer labels.
4029 *
4030 */
4031static int selinux_skb_peerlbl_sid(struct sk_buff *skb, u16 family, u32 *sid)
4032{
4033 int err;
4034 u32 xfrm_sid;
4035 u32 nlbl_sid;
4036 u32 nlbl_type;
4037
4038 err = selinux_xfrm_skb_sid(skb, &xfrm_sid);
4039 if (unlikely(err))
4040 return -EACCES;
4041 err = selinux_netlbl_skbuff_getsid(skb, family, &nlbl_type, &nlbl_sid);
4042 if (unlikely(err))
4043 return -EACCES;
4044
4045 err = security_net_peersid_resolve(nlbl_sid, nlbl_type, xfrm_sid, sid);
4046 if (unlikely(err)) {
4047 printk(KERN_WARNING
4048 "SELinux: failure in selinux_skb_peerlbl_sid(),"
4049 " unable to determine packet's peer label\n");
4050 return -EACCES;
4051 }
4052
4053 return 0;
4054}
4055
4056/**
4057 * selinux_conn_sid - Determine the child socket label for a connection
4058 * @sk_sid: the parent socket's SID
4059 * @skb_sid: the packet's SID
4060 * @conn_sid: the resulting connection SID
4061 *
4062 * If @skb_sid is valid then the user:role:type information from @sk_sid is
4063 * combined with the MLS information from @skb_sid in order to create
4064 * @conn_sid. If @skb_sid is not valid then then @conn_sid is simply a copy
4065 * of @sk_sid. Returns zero on success, negative values on failure.
4066 *
4067 */
4068static int selinux_conn_sid(u32 sk_sid, u32 skb_sid, u32 *conn_sid)
4069{
4070 int err = 0;
4071
4072 if (skb_sid != SECSID_NULL)
4073 err = security_sid_mls_copy(sk_sid, skb_sid, conn_sid);
4074 else
4075 *conn_sid = sk_sid;
4076
4077 return err;
4078}
4079
4080/* socket security operations */
4081
4082static int socket_sockcreate_sid(const struct task_security_struct *tsec,
4083 u16 secclass, u32 *socksid)
4084{
4085 if (tsec->sockcreate_sid > SECSID_NULL) {
4086 *socksid = tsec->sockcreate_sid;
4087 return 0;
4088 }
4089
4090 return security_transition_sid(tsec->sid, tsec->sid, secclass, NULL,
4091 socksid);
4092}
4093
4094static int sock_has_perm(struct task_struct *task, struct sock *sk, u32 perms)
4095{
4096 struct sk_security_struct *sksec = sk->sk_security;
4097 struct common_audit_data ad;
4098 struct lsm_network_audit net = {0,};
4099 u32 tsid = task_sid(task);
4100
4101 if (sksec->sid == SECINITSID_KERNEL)
4102 return 0;
4103
4104 ad.type = LSM_AUDIT_DATA_NET;
4105 ad.u.net = &net;
4106 ad.u.net->sk = sk;
4107
4108 return avc_has_perm(tsid, sksec->sid, sksec->sclass, perms, &ad);
4109}
4110
4111static int selinux_socket_create(int family, int type,
4112 int protocol, int kern)
4113{
4114 const struct task_security_struct *tsec = current_security();
4115 u32 newsid;
4116 u16 secclass;
4117 int rc;
4118
4119 if (kern)
4120 return 0;
4121
4122 secclass = socket_type_to_security_class(family, type, protocol);
4123 rc = socket_sockcreate_sid(tsec, secclass, &newsid);
4124 if (rc)
4125 return rc;
4126
4127 return avc_has_perm(tsec->sid, newsid, secclass, SOCKET__CREATE, NULL);
4128}
4129
4130static int selinux_socket_post_create(struct socket *sock, int family,
4131 int type, int protocol, int kern)
4132{
4133 const struct task_security_struct *tsec = current_security();
4134 struct inode_security_struct *isec = inode_security_novalidate(SOCK_INODE(sock));
4135 struct sk_security_struct *sksec;
4136 int err = 0;
4137
4138 isec->sclass = socket_type_to_security_class(family, type, protocol);
4139
4140 if (kern)
4141 isec->sid = SECINITSID_KERNEL;
4142 else {
4143 err = socket_sockcreate_sid(tsec, isec->sclass, &(isec->sid));
4144 if (err)
4145 return err;
4146 }
4147
4148 isec->initialized = LABEL_INITIALIZED;
4149
4150 if (sock->sk) {
4151 sksec = sock->sk->sk_security;
4152 sksec->sid = isec->sid;
4153 sksec->sclass = isec->sclass;
4154 err = selinux_netlbl_socket_post_create(sock->sk, family);
4155 }
4156
4157 return err;
4158}
4159
4160/* Range of port numbers used to automatically bind.
4161 Need to determine whether we should perform a name_bind
4162 permission check between the socket and the port number. */
4163
4164static int selinux_socket_bind(struct socket *sock, struct sockaddr *address, int addrlen)
4165{
4166 struct sock *sk = sock->sk;
4167 u16 family;
4168 int err;
4169
4170 err = sock_has_perm(current, sk, SOCKET__BIND);
4171 if (err)
4172 goto out;
4173
4174 /*
4175 * If PF_INET or PF_INET6, check name_bind permission for the port.
4176 * Multiple address binding for SCTP is not supported yet: we just
4177 * check the first address now.
4178 */
4179 family = sk->sk_family;
4180 if (family == PF_INET || family == PF_INET6) {
4181 char *addrp;
4182 struct sk_security_struct *sksec = sk->sk_security;
4183 struct common_audit_data ad;
4184 struct lsm_network_audit net = {0,};
4185 struct sockaddr_in *addr4 = NULL;
4186 struct sockaddr_in6 *addr6 = NULL;
4187 unsigned short snum;
4188 u32 sid, node_perm;
4189
4190 if (family == PF_INET) {
4191 addr4 = (struct sockaddr_in *)address;
4192 snum = ntohs(addr4->sin_port);
4193 addrp = (char *)&addr4->sin_addr.s_addr;
4194 } else {
4195 addr6 = (struct sockaddr_in6 *)address;
4196 snum = ntohs(addr6->sin6_port);
4197 addrp = (char *)&addr6->sin6_addr.s6_addr;
4198 }
4199
4200 if (snum) {
4201 int low, high;
4202
4203 inet_get_local_port_range(sock_net(sk), &low, &high);
4204
4205 if (snum < max(PROT_SOCK, low) || snum > high) {
4206 err = sel_netport_sid(sk->sk_protocol,
4207 snum, &sid);
4208 if (err)
4209 goto out;
4210 ad.type = LSM_AUDIT_DATA_NET;
4211 ad.u.net = &net;
4212 ad.u.net->sport = htons(snum);
4213 ad.u.net->family = family;
4214 err = avc_has_perm(sksec->sid, sid,
4215 sksec->sclass,
4216 SOCKET__NAME_BIND, &ad);
4217 if (err)
4218 goto out;
4219 }
4220 }
4221
4222 switch (sksec->sclass) {
4223 case SECCLASS_TCP_SOCKET:
4224 node_perm = TCP_SOCKET__NODE_BIND;
4225 break;
4226
4227 case SECCLASS_UDP_SOCKET:
4228 node_perm = UDP_SOCKET__NODE_BIND;
4229 break;
4230
4231 case SECCLASS_DCCP_SOCKET:
4232 node_perm = DCCP_SOCKET__NODE_BIND;
4233 break;
4234
4235 default:
4236 node_perm = RAWIP_SOCKET__NODE_BIND;
4237 break;
4238 }
4239
4240 err = sel_netnode_sid(addrp, family, &sid);
4241 if (err)
4242 goto out;
4243
4244 ad.type = LSM_AUDIT_DATA_NET;
4245 ad.u.net = &net;
4246 ad.u.net->sport = htons(snum);
4247 ad.u.net->family = family;
4248
4249 if (family == PF_INET)
4250 ad.u.net->v4info.saddr = addr4->sin_addr.s_addr;
4251 else
4252 ad.u.net->v6info.saddr = addr6->sin6_addr;
4253
4254 err = avc_has_perm(sksec->sid, sid,
4255 sksec->sclass, node_perm, &ad);
4256 if (err)
4257 goto out;
4258 }
4259out:
4260 return err;
4261}
4262
4263static int selinux_socket_connect(struct socket *sock, struct sockaddr *address, int addrlen)
4264{
4265 struct sock *sk = sock->sk;
4266 struct sk_security_struct *sksec = sk->sk_security;
4267 int err;
4268
4269 err = sock_has_perm(current, sk, SOCKET__CONNECT);
4270 if (err)
4271 return err;
4272
4273 /*
4274 * If a TCP or DCCP socket, check name_connect permission for the port.
4275 */
4276 if (sksec->sclass == SECCLASS_TCP_SOCKET ||
4277 sksec->sclass == SECCLASS_DCCP_SOCKET) {
4278 struct common_audit_data ad;
4279 struct lsm_network_audit net = {0,};
4280 struct sockaddr_in *addr4 = NULL;
4281 struct sockaddr_in6 *addr6 = NULL;
4282 unsigned short snum;
4283 u32 sid, perm;
4284
4285 if (sk->sk_family == PF_INET) {
4286 addr4 = (struct sockaddr_in *)address;
4287 if (addrlen < sizeof(struct sockaddr_in))
4288 return -EINVAL;
4289 snum = ntohs(addr4->sin_port);
4290 } else {
4291 addr6 = (struct sockaddr_in6 *)address;
4292 if (addrlen < SIN6_LEN_RFC2133)
4293 return -EINVAL;
4294 snum = ntohs(addr6->sin6_port);
4295 }
4296
4297 err = sel_netport_sid(sk->sk_protocol, snum, &sid);
4298 if (err)
4299 goto out;
4300
4301 perm = (sksec->sclass == SECCLASS_TCP_SOCKET) ?
4302 TCP_SOCKET__NAME_CONNECT : DCCP_SOCKET__NAME_CONNECT;
4303
4304 ad.type = LSM_AUDIT_DATA_NET;
4305 ad.u.net = &net;
4306 ad.u.net->dport = htons(snum);
4307 ad.u.net->family = sk->sk_family;
4308 err = avc_has_perm(sksec->sid, sid, sksec->sclass, perm, &ad);
4309 if (err)
4310 goto out;
4311 }
4312
4313 err = selinux_netlbl_socket_connect(sk, address);
4314
4315out:
4316 return err;
4317}
4318
4319static int selinux_socket_listen(struct socket *sock, int backlog)
4320{
4321 return sock_has_perm(current, sock->sk, SOCKET__LISTEN);
4322}
4323
4324static int selinux_socket_accept(struct socket *sock, struct socket *newsock)
4325{
4326 int err;
4327 struct inode_security_struct *isec;
4328 struct inode_security_struct *newisec;
4329
4330 err = sock_has_perm(current, sock->sk, SOCKET__ACCEPT);
4331 if (err)
4332 return err;
4333
4334 newisec = inode_security_novalidate(SOCK_INODE(newsock));
4335
4336 isec = inode_security_novalidate(SOCK_INODE(sock));
4337 newisec->sclass = isec->sclass;
4338 newisec->sid = isec->sid;
4339 newisec->initialized = LABEL_INITIALIZED;
4340
4341 return 0;
4342}
4343
4344static int selinux_socket_sendmsg(struct socket *sock, struct msghdr *msg,
4345 int size)
4346{
4347 return sock_has_perm(current, sock->sk, SOCKET__WRITE);
4348}
4349
4350static int selinux_socket_recvmsg(struct socket *sock, struct msghdr *msg,
4351 int size, int flags)
4352{
4353 return sock_has_perm(current, sock->sk, SOCKET__READ);
4354}
4355
4356static int selinux_socket_getsockname(struct socket *sock)
4357{
4358 return sock_has_perm(current, sock->sk, SOCKET__GETATTR);
4359}
4360
4361static int selinux_socket_getpeername(struct socket *sock)
4362{
4363 return sock_has_perm(current, sock->sk, SOCKET__GETATTR);
4364}
4365
4366static int selinux_socket_setsockopt(struct socket *sock, int level, int optname)
4367{
4368 int err;
4369
4370 err = sock_has_perm(current, sock->sk, SOCKET__SETOPT);
4371 if (err)
4372 return err;
4373
4374 return selinux_netlbl_socket_setsockopt(sock, level, optname);
4375}
4376
4377static int selinux_socket_getsockopt(struct socket *sock, int level,
4378 int optname)
4379{
4380 return sock_has_perm(current, sock->sk, SOCKET__GETOPT);
4381}
4382
4383static int selinux_socket_shutdown(struct socket *sock, int how)
4384{
4385 return sock_has_perm(current, sock->sk, SOCKET__SHUTDOWN);
4386}
4387
4388static int selinux_socket_unix_stream_connect(struct sock *sock,
4389 struct sock *other,
4390 struct sock *newsk)
4391{
4392 struct sk_security_struct *sksec_sock = sock->sk_security;
4393 struct sk_security_struct *sksec_other = other->sk_security;
4394 struct sk_security_struct *sksec_new = newsk->sk_security;
4395 struct common_audit_data ad;
4396 struct lsm_network_audit net = {0,};
4397 int err;
4398
4399 ad.type = LSM_AUDIT_DATA_NET;
4400 ad.u.net = &net;
4401 ad.u.net->sk = other;
4402
4403 err = avc_has_perm(sksec_sock->sid, sksec_other->sid,
4404 sksec_other->sclass,
4405 UNIX_STREAM_SOCKET__CONNECTTO, &ad);
4406 if (err)
4407 return err;
4408
4409 /* server child socket */
4410 sksec_new->peer_sid = sksec_sock->sid;
4411 err = security_sid_mls_copy(sksec_other->sid, sksec_sock->sid,
4412 &sksec_new->sid);
4413 if (err)
4414 return err;
4415
4416 /* connecting socket */
4417 sksec_sock->peer_sid = sksec_new->sid;
4418
4419 return 0;
4420}
4421
4422static int selinux_socket_unix_may_send(struct socket *sock,
4423 struct socket *other)
4424{
4425 struct sk_security_struct *ssec = sock->sk->sk_security;
4426 struct sk_security_struct *osec = other->sk->sk_security;
4427 struct common_audit_data ad;
4428 struct lsm_network_audit net = {0,};
4429
4430 ad.type = LSM_AUDIT_DATA_NET;
4431 ad.u.net = &net;
4432 ad.u.net->sk = other->sk;
4433
4434 return avc_has_perm(ssec->sid, osec->sid, osec->sclass, SOCKET__SENDTO,
4435 &ad);
4436}
4437
4438static int selinux_inet_sys_rcv_skb(struct net *ns, int ifindex,
4439 char *addrp, u16 family, u32 peer_sid,
4440 struct common_audit_data *ad)
4441{
4442 int err;
4443 u32 if_sid;
4444 u32 node_sid;
4445
4446 err = sel_netif_sid(ns, ifindex, &if_sid);
4447 if (err)
4448 return err;
4449 err = avc_has_perm(peer_sid, if_sid,
4450 SECCLASS_NETIF, NETIF__INGRESS, ad);
4451 if (err)
4452 return err;
4453
4454 err = sel_netnode_sid(addrp, family, &node_sid);
4455 if (err)
4456 return err;
4457 return avc_has_perm(peer_sid, node_sid,
4458 SECCLASS_NODE, NODE__RECVFROM, ad);
4459}
4460
4461static int selinux_sock_rcv_skb_compat(struct sock *sk, struct sk_buff *skb,
4462 u16 family)
4463{
4464 int err = 0;
4465 struct sk_security_struct *sksec = sk->sk_security;
4466 u32 sk_sid = sksec->sid;
4467 struct common_audit_data ad;
4468 struct lsm_network_audit net = {0,};
4469 char *addrp;
4470
4471 ad.type = LSM_AUDIT_DATA_NET;
4472 ad.u.net = &net;
4473 ad.u.net->netif = skb->skb_iif;
4474 ad.u.net->family = family;
4475 err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL);
4476 if (err)
4477 return err;
4478
4479 if (selinux_secmark_enabled()) {
4480 err = avc_has_perm(sk_sid, skb->secmark, SECCLASS_PACKET,
4481 PACKET__RECV, &ad);
4482 if (err)
4483 return err;
4484 }
4485
4486 err = selinux_netlbl_sock_rcv_skb(sksec, skb, family, &ad);
4487 if (err)
4488 return err;
4489 err = selinux_xfrm_sock_rcv_skb(sksec->sid, skb, &ad);
4490
4491 return err;
4492}
4493
4494static int selinux_socket_sock_rcv_skb(struct sock *sk, struct sk_buff *skb)
4495{
4496 int err;
4497 struct sk_security_struct *sksec = sk->sk_security;
4498 u16 family = sk->sk_family;
4499 u32 sk_sid = sksec->sid;
4500 struct common_audit_data ad;
4501 struct lsm_network_audit net = {0,};
4502 char *addrp;
4503 u8 secmark_active;
4504 u8 peerlbl_active;
4505
4506 if (family != PF_INET && family != PF_INET6)
4507 return 0;
4508
4509 /* Handle mapped IPv4 packets arriving via IPv6 sockets */
4510 if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
4511 family = PF_INET;
4512
4513 /* If any sort of compatibility mode is enabled then handoff processing
4514 * to the selinux_sock_rcv_skb_compat() function to deal with the
4515 * special handling. We do this in an attempt to keep this function
4516 * as fast and as clean as possible. */
4517 if (!selinux_policycap_netpeer)
4518 return selinux_sock_rcv_skb_compat(sk, skb, family);
4519
4520 secmark_active = selinux_secmark_enabled();
4521 peerlbl_active = selinux_peerlbl_enabled();
4522 if (!secmark_active && !peerlbl_active)
4523 return 0;
4524
4525 ad.type = LSM_AUDIT_DATA_NET;
4526 ad.u.net = &net;
4527 ad.u.net->netif = skb->skb_iif;
4528 ad.u.net->family = family;
4529 err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL);
4530 if (err)
4531 return err;
4532
4533 if (peerlbl_active) {
4534 u32 peer_sid;
4535
4536 err = selinux_skb_peerlbl_sid(skb, family, &peer_sid);
4537 if (err)
4538 return err;
4539 err = selinux_inet_sys_rcv_skb(sock_net(sk), skb->skb_iif,
4540 addrp, family, peer_sid, &ad);
4541 if (err) {
4542 selinux_netlbl_err(skb, err, 0);
4543 return err;
4544 }
4545 err = avc_has_perm(sk_sid, peer_sid, SECCLASS_PEER,
4546 PEER__RECV, &ad);
4547 if (err) {
4548 selinux_netlbl_err(skb, err, 0);
4549 return err;
4550 }
4551 }
4552
4553 if (secmark_active) {
4554 err = avc_has_perm(sk_sid, skb->secmark, SECCLASS_PACKET,
4555 PACKET__RECV, &ad);
4556 if (err)
4557 return err;
4558 }
4559
4560 return err;
4561}
4562
4563static int selinux_socket_getpeersec_stream(struct socket *sock, char __user *optval,
4564 int __user *optlen, unsigned len)
4565{
4566 int err = 0;
4567 char *scontext;
4568 u32 scontext_len;
4569 struct sk_security_struct *sksec = sock->sk->sk_security;
4570 u32 peer_sid = SECSID_NULL;
4571
4572 if (sksec->sclass == SECCLASS_UNIX_STREAM_SOCKET ||
4573 sksec->sclass == SECCLASS_TCP_SOCKET)
4574 peer_sid = sksec->peer_sid;
4575 if (peer_sid == SECSID_NULL)
4576 return -ENOPROTOOPT;
4577
4578 err = security_sid_to_context(peer_sid, &scontext, &scontext_len);
4579 if (err)
4580 return err;
4581
4582 if (scontext_len > len) {
4583 err = -ERANGE;
4584 goto out_len;
4585 }
4586
4587 if (copy_to_user(optval, scontext, scontext_len))
4588 err = -EFAULT;
4589
4590out_len:
4591 if (put_user(scontext_len, optlen))
4592 err = -EFAULT;
4593 kfree(scontext);
4594 return err;
4595}
4596
4597static int selinux_socket_getpeersec_dgram(struct socket *sock, struct sk_buff *skb, u32 *secid)
4598{
4599 u32 peer_secid = SECSID_NULL;
4600 u16 family;
4601
4602 if (skb && skb->protocol == htons(ETH_P_IP))
4603 family = PF_INET;
4604 else if (skb && skb->protocol == htons(ETH_P_IPV6))
4605 family = PF_INET6;
4606 else if (sock)
4607 family = sock->sk->sk_family;
4608 else
4609 goto out;
4610
4611 if (sock && family == PF_UNIX)
4612 selinux_inode_getsecid(SOCK_INODE(sock), &peer_secid);
4613 else if (skb)
4614 selinux_skb_peerlbl_sid(skb, family, &peer_secid);
4615
4616out:
4617 *secid = peer_secid;
4618 if (peer_secid == SECSID_NULL)
4619 return -EINVAL;
4620 return 0;
4621}
4622
4623static int selinux_sk_alloc_security(struct sock *sk, int family, gfp_t priority)
4624{
4625 struct sk_security_struct *sksec;
4626
4627 sksec = kzalloc(sizeof(*sksec), priority);
4628 if (!sksec)
4629 return -ENOMEM;
4630
4631 sksec->peer_sid = SECINITSID_UNLABELED;
4632 sksec->sid = SECINITSID_UNLABELED;
4633 sksec->sclass = SECCLASS_SOCKET;
4634 selinux_netlbl_sk_security_reset(sksec);
4635 sk->sk_security = sksec;
4636
4637 return 0;
4638}
4639
4640static void selinux_sk_free_security(struct sock *sk)
4641{
4642 struct sk_security_struct *sksec = sk->sk_security;
4643
4644 sk->sk_security = NULL;
4645 selinux_netlbl_sk_security_free(sksec);
4646 kfree(sksec);
4647}
4648
4649static void selinux_sk_clone_security(const struct sock *sk, struct sock *newsk)
4650{
4651 struct sk_security_struct *sksec = sk->sk_security;
4652 struct sk_security_struct *newsksec = newsk->sk_security;
4653
4654 newsksec->sid = sksec->sid;
4655 newsksec->peer_sid = sksec->peer_sid;
4656 newsksec->sclass = sksec->sclass;
4657
4658 selinux_netlbl_sk_security_reset(newsksec);
4659}
4660
4661static void selinux_sk_getsecid(struct sock *sk, u32 *secid)
4662{
4663 if (!sk)
4664 *secid = SECINITSID_ANY_SOCKET;
4665 else {
4666 struct sk_security_struct *sksec = sk->sk_security;
4667
4668 *secid = sksec->sid;
4669 }
4670}
4671
4672static void selinux_sock_graft(struct sock *sk, struct socket *parent)
4673{
4674 struct inode_security_struct *isec =
4675 inode_security_novalidate(SOCK_INODE(parent));
4676 struct sk_security_struct *sksec = sk->sk_security;
4677
4678 if (sk->sk_family == PF_INET || sk->sk_family == PF_INET6 ||
4679 sk->sk_family == PF_UNIX)
4680 isec->sid = sksec->sid;
4681 sksec->sclass = isec->sclass;
4682}
4683
4684static int selinux_inet_conn_request(struct sock *sk, struct sk_buff *skb,
4685 struct request_sock *req)
4686{
4687 struct sk_security_struct *sksec = sk->sk_security;
4688 int err;
4689 u16 family = req->rsk_ops->family;
4690 u32 connsid;
4691 u32 peersid;
4692
4693 err = selinux_skb_peerlbl_sid(skb, family, &peersid);
4694 if (err)
4695 return err;
4696 err = selinux_conn_sid(sksec->sid, peersid, &connsid);
4697 if (err)
4698 return err;
4699 req->secid = connsid;
4700 req->peer_secid = peersid;
4701
4702 return selinux_netlbl_inet_conn_request(req, family);
4703}
4704
4705static void selinux_inet_csk_clone(struct sock *newsk,
4706 const struct request_sock *req)
4707{
4708 struct sk_security_struct *newsksec = newsk->sk_security;
4709
4710 newsksec->sid = req->secid;
4711 newsksec->peer_sid = req->peer_secid;
4712 /* NOTE: Ideally, we should also get the isec->sid for the
4713 new socket in sync, but we don't have the isec available yet.
4714 So we will wait until sock_graft to do it, by which
4715 time it will have been created and available. */
4716
4717 /* We don't need to take any sort of lock here as we are the only
4718 * thread with access to newsksec */
4719 selinux_netlbl_inet_csk_clone(newsk, req->rsk_ops->family);
4720}
4721
4722static void selinux_inet_conn_established(struct sock *sk, struct sk_buff *skb)
4723{
4724 u16 family = sk->sk_family;
4725 struct sk_security_struct *sksec = sk->sk_security;
4726
4727 /* handle mapped IPv4 packets arriving via IPv6 sockets */
4728 if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
4729 family = PF_INET;
4730
4731 selinux_skb_peerlbl_sid(skb, family, &sksec->peer_sid);
4732}
4733
4734static int selinux_secmark_relabel_packet(u32 sid)
4735{
4736 const struct task_security_struct *__tsec;
4737 u32 tsid;
4738
4739 __tsec = current_security();
4740 tsid = __tsec->sid;
4741
4742 return avc_has_perm(tsid, sid, SECCLASS_PACKET, PACKET__RELABELTO, NULL);
4743}
4744
4745static void selinux_secmark_refcount_inc(void)
4746{
4747 atomic_inc(&selinux_secmark_refcount);
4748}
4749
4750static void selinux_secmark_refcount_dec(void)
4751{
4752 atomic_dec(&selinux_secmark_refcount);
4753}
4754
4755static void selinux_req_classify_flow(const struct request_sock *req,
4756 struct flowi *fl)
4757{
4758 fl->flowi_secid = req->secid;
4759}
4760
4761static int selinux_tun_dev_alloc_security(void **security)
4762{
4763 struct tun_security_struct *tunsec;
4764
4765 tunsec = kzalloc(sizeof(*tunsec), GFP_KERNEL);
4766 if (!tunsec)
4767 return -ENOMEM;
4768 tunsec->sid = current_sid();
4769
4770 *security = tunsec;
4771 return 0;
4772}
4773
4774static void selinux_tun_dev_free_security(void *security)
4775{
4776 kfree(security);
4777}
4778
4779static int selinux_tun_dev_create(void)
4780{
4781 u32 sid = current_sid();
4782
4783 /* we aren't taking into account the "sockcreate" SID since the socket
4784 * that is being created here is not a socket in the traditional sense,
4785 * instead it is a private sock, accessible only to the kernel, and
4786 * representing a wide range of network traffic spanning multiple
4787 * connections unlike traditional sockets - check the TUN driver to
4788 * get a better understanding of why this socket is special */
4789
4790 return avc_has_perm(sid, sid, SECCLASS_TUN_SOCKET, TUN_SOCKET__CREATE,
4791 NULL);
4792}
4793
4794static int selinux_tun_dev_attach_queue(void *security)
4795{
4796 struct tun_security_struct *tunsec = security;
4797
4798 return avc_has_perm(current_sid(), tunsec->sid, SECCLASS_TUN_SOCKET,
4799 TUN_SOCKET__ATTACH_QUEUE, NULL);
4800}
4801
4802static int selinux_tun_dev_attach(struct sock *sk, void *security)
4803{
4804 struct tun_security_struct *tunsec = security;
4805 struct sk_security_struct *sksec = sk->sk_security;
4806
4807 /* we don't currently perform any NetLabel based labeling here and it
4808 * isn't clear that we would want to do so anyway; while we could apply
4809 * labeling without the support of the TUN user the resulting labeled
4810 * traffic from the other end of the connection would almost certainly
4811 * cause confusion to the TUN user that had no idea network labeling
4812 * protocols were being used */
4813
4814 sksec->sid = tunsec->sid;
4815 sksec->sclass = SECCLASS_TUN_SOCKET;
4816
4817 return 0;
4818}
4819
4820static int selinux_tun_dev_open(void *security)
4821{
4822 struct tun_security_struct *tunsec = security;
4823 u32 sid = current_sid();
4824 int err;
4825
4826 err = avc_has_perm(sid, tunsec->sid, SECCLASS_TUN_SOCKET,
4827 TUN_SOCKET__RELABELFROM, NULL);
4828 if (err)
4829 return err;
4830 err = avc_has_perm(sid, sid, SECCLASS_TUN_SOCKET,
4831 TUN_SOCKET__RELABELTO, NULL);
4832 if (err)
4833 return err;
4834 tunsec->sid = sid;
4835
4836 return 0;
4837}
4838
4839static int selinux_nlmsg_perm(struct sock *sk, struct sk_buff *skb)
4840{
4841 int err = 0;
4842 u32 perm;
4843 struct nlmsghdr *nlh;
4844 struct sk_security_struct *sksec = sk->sk_security;
4845
4846 if (skb->len < NLMSG_HDRLEN) {
4847 err = -EINVAL;
4848 goto out;
4849 }
4850 nlh = nlmsg_hdr(skb);
4851
4852 err = selinux_nlmsg_lookup(sksec->sclass, nlh->nlmsg_type, &perm);
4853 if (err) {
4854 if (err == -EINVAL) {
4855 pr_warn_ratelimited("SELinux: unrecognized netlink"
4856 " message: protocol=%hu nlmsg_type=%hu sclass=%s"
4857 " pig=%d comm=%s\n",
4858 sk->sk_protocol, nlh->nlmsg_type,
4859 secclass_map[sksec->sclass - 1].name,
4860 task_pid_nr(current), current->comm);
4861 if (!selinux_enforcing || security_get_allow_unknown())
4862 err = 0;
4863 }
4864
4865 /* Ignore */
4866 if (err == -ENOENT)
4867 err = 0;
4868 goto out;
4869 }
4870
4871 err = sock_has_perm(current, sk, perm);
4872out:
4873 return err;
4874}
4875
4876#ifdef CONFIG_NETFILTER
4877
4878static unsigned int selinux_ip_forward(struct sk_buff *skb,
4879 const struct net_device *indev,
4880 u16 family)
4881{
4882 int err;
4883 char *addrp;
4884 u32 peer_sid;
4885 struct common_audit_data ad;
4886 struct lsm_network_audit net = {0,};
4887 u8 secmark_active;
4888 u8 netlbl_active;
4889 u8 peerlbl_active;
4890
4891 if (!selinux_policycap_netpeer)
4892 return NF_ACCEPT;
4893
4894 secmark_active = selinux_secmark_enabled();
4895 netlbl_active = netlbl_enabled();
4896 peerlbl_active = selinux_peerlbl_enabled();
4897 if (!secmark_active && !peerlbl_active)
4898 return NF_ACCEPT;
4899
4900 if (selinux_skb_peerlbl_sid(skb, family, &peer_sid) != 0)
4901 return NF_DROP;
4902
4903 ad.type = LSM_AUDIT_DATA_NET;
4904 ad.u.net = &net;
4905 ad.u.net->netif = indev->ifindex;
4906 ad.u.net->family = family;
4907 if (selinux_parse_skb(skb, &ad, &addrp, 1, NULL) != 0)
4908 return NF_DROP;
4909
4910 if (peerlbl_active) {
4911 err = selinux_inet_sys_rcv_skb(dev_net(indev), indev->ifindex,
4912 addrp, family, peer_sid, &ad);
4913 if (err) {
4914 selinux_netlbl_err(skb, err, 1);
4915 return NF_DROP;
4916 }
4917 }
4918
4919 if (secmark_active)
4920 if (avc_has_perm(peer_sid, skb->secmark,
4921 SECCLASS_PACKET, PACKET__FORWARD_IN, &ad))
4922 return NF_DROP;
4923
4924 if (netlbl_active)
4925 /* we do this in the FORWARD path and not the POST_ROUTING
4926 * path because we want to make sure we apply the necessary
4927 * labeling before IPsec is applied so we can leverage AH
4928 * protection */
4929 if (selinux_netlbl_skbuff_setsid(skb, family, peer_sid) != 0)
4930 return NF_DROP;
4931
4932 return NF_ACCEPT;
4933}
4934
4935static unsigned int selinux_ipv4_forward(void *priv,
4936 struct sk_buff *skb,
4937 const struct nf_hook_state *state)
4938{
4939 return selinux_ip_forward(skb, state->in, PF_INET);
4940}
4941
4942#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
4943static unsigned int selinux_ipv6_forward(void *priv,
4944 struct sk_buff *skb,
4945 const struct nf_hook_state *state)
4946{
4947 return selinux_ip_forward(skb, state->in, PF_INET6);
4948}
4949#endif /* IPV6 */
4950
4951static unsigned int selinux_ip_output(struct sk_buff *skb,
4952 u16 family)
4953{
4954 struct sock *sk;
4955 u32 sid;
4956
4957 if (!netlbl_enabled())
4958 return NF_ACCEPT;
4959
4960 /* we do this in the LOCAL_OUT path and not the POST_ROUTING path
4961 * because we want to make sure we apply the necessary labeling
4962 * before IPsec is applied so we can leverage AH protection */
4963 sk = skb->sk;
4964 if (sk) {
4965 struct sk_security_struct *sksec;
4966
4967 if (sk_listener(sk))
4968 /* if the socket is the listening state then this
4969 * packet is a SYN-ACK packet which means it needs to
4970 * be labeled based on the connection/request_sock and
4971 * not the parent socket. unfortunately, we can't
4972 * lookup the request_sock yet as it isn't queued on
4973 * the parent socket until after the SYN-ACK is sent.
4974 * the "solution" is to simply pass the packet as-is
4975 * as any IP option based labeling should be copied
4976 * from the initial connection request (in the IP
4977 * layer). it is far from ideal, but until we get a
4978 * security label in the packet itself this is the
4979 * best we can do. */
4980 return NF_ACCEPT;
4981
4982 /* standard practice, label using the parent socket */
4983 sksec = sk->sk_security;
4984 sid = sksec->sid;
4985 } else
4986 sid = SECINITSID_KERNEL;
4987 if (selinux_netlbl_skbuff_setsid(skb, family, sid) != 0)
4988 return NF_DROP;
4989
4990 return NF_ACCEPT;
4991}
4992
4993static unsigned int selinux_ipv4_output(void *priv,
4994 struct sk_buff *skb,
4995 const struct nf_hook_state *state)
4996{
4997 return selinux_ip_output(skb, PF_INET);
4998}
4999
5000static unsigned int selinux_ip_postroute_compat(struct sk_buff *skb,
5001 int ifindex,
5002 u16 family)
5003{
5004 struct sock *sk = skb_to_full_sk(skb);
5005 struct sk_security_struct *sksec;
5006 struct common_audit_data ad;
5007 struct lsm_network_audit net = {0,};
5008 char *addrp;
5009 u8 proto;
5010
5011 if (sk == NULL)
5012 return NF_ACCEPT;
5013 sksec = sk->sk_security;
5014
5015 ad.type = LSM_AUDIT_DATA_NET;
5016 ad.u.net = &net;
5017 ad.u.net->netif = ifindex;
5018 ad.u.net->family = family;
5019 if (selinux_parse_skb(skb, &ad, &addrp, 0, &proto))
5020 return NF_DROP;
5021
5022 if (selinux_secmark_enabled())
5023 if (avc_has_perm(sksec->sid, skb->secmark,
5024 SECCLASS_PACKET, PACKET__SEND, &ad))
5025 return NF_DROP_ERR(-ECONNREFUSED);
5026
5027 if (selinux_xfrm_postroute_last(sksec->sid, skb, &ad, proto))
5028 return NF_DROP_ERR(-ECONNREFUSED);
5029
5030 return NF_ACCEPT;
5031}
5032
5033static unsigned int selinux_ip_postroute(struct sk_buff *skb,
5034 const struct net_device *outdev,
5035 u16 family)
5036{
5037 u32 secmark_perm;
5038 u32 peer_sid;
5039 int ifindex = outdev->ifindex;
5040 struct sock *sk;
5041 struct common_audit_data ad;
5042 struct lsm_network_audit net = {0,};
5043 char *addrp;
5044 u8 secmark_active;
5045 u8 peerlbl_active;
5046
5047 /* If any sort of compatibility mode is enabled then handoff processing
5048 * to the selinux_ip_postroute_compat() function to deal with the
5049 * special handling. We do this in an attempt to keep this function
5050 * as fast and as clean as possible. */
5051 if (!selinux_policycap_netpeer)
5052 return selinux_ip_postroute_compat(skb, ifindex, family);
5053
5054 secmark_active = selinux_secmark_enabled();
5055 peerlbl_active = selinux_peerlbl_enabled();
5056 if (!secmark_active && !peerlbl_active)
5057 return NF_ACCEPT;
5058
5059 sk = skb_to_full_sk(skb);
5060
5061#ifdef CONFIG_XFRM
5062 /* If skb->dst->xfrm is non-NULL then the packet is undergoing an IPsec
5063 * packet transformation so allow the packet to pass without any checks
5064 * since we'll have another chance to perform access control checks
5065 * when the packet is on it's final way out.
5066 * NOTE: there appear to be some IPv6 multicast cases where skb->dst
5067 * is NULL, in this case go ahead and apply access control.
5068 * NOTE: if this is a local socket (skb->sk != NULL) that is in the
5069 * TCP listening state we cannot wait until the XFRM processing
5070 * is done as we will miss out on the SA label if we do;
5071 * unfortunately, this means more work, but it is only once per
5072 * connection. */
5073 if (skb_dst(skb) != NULL && skb_dst(skb)->xfrm != NULL &&
5074 !(sk && sk_listener(sk)))
5075 return NF_ACCEPT;
5076#endif
5077
5078 if (sk == NULL) {
5079 /* Without an associated socket the packet is either coming
5080 * from the kernel or it is being forwarded; check the packet
5081 * to determine which and if the packet is being forwarded
5082 * query the packet directly to determine the security label. */
5083 if (skb->skb_iif) {
5084 secmark_perm = PACKET__FORWARD_OUT;
5085 if (selinux_skb_peerlbl_sid(skb, family, &peer_sid))
5086 return NF_DROP;
5087 } else {
5088 secmark_perm = PACKET__SEND;
5089 peer_sid = SECINITSID_KERNEL;
5090 }
5091 } else if (sk_listener(sk)) {
5092 /* Locally generated packet but the associated socket is in the
5093 * listening state which means this is a SYN-ACK packet. In
5094 * this particular case the correct security label is assigned
5095 * to the connection/request_sock but unfortunately we can't
5096 * query the request_sock as it isn't queued on the parent
5097 * socket until after the SYN-ACK packet is sent; the only
5098 * viable choice is to regenerate the label like we do in
5099 * selinux_inet_conn_request(). See also selinux_ip_output()
5100 * for similar problems. */
5101 u32 skb_sid;
5102 struct sk_security_struct *sksec;
5103
5104 sksec = sk->sk_security;
5105 if (selinux_skb_peerlbl_sid(skb, family, &skb_sid))
5106 return NF_DROP;
5107 /* At this point, if the returned skb peerlbl is SECSID_NULL
5108 * and the packet has been through at least one XFRM
5109 * transformation then we must be dealing with the "final"
5110 * form of labeled IPsec packet; since we've already applied
5111 * all of our access controls on this packet we can safely
5112 * pass the packet. */
5113 if (skb_sid == SECSID_NULL) {
5114 switch (family) {
5115 case PF_INET:
5116 if (IPCB(skb)->flags & IPSKB_XFRM_TRANSFORMED)
5117 return NF_ACCEPT;
5118 break;
5119 case PF_INET6:
5120 if (IP6CB(skb)->flags & IP6SKB_XFRM_TRANSFORMED)
5121 return NF_ACCEPT;
5122 break;
5123 default:
5124 return NF_DROP_ERR(-ECONNREFUSED);
5125 }
5126 }
5127 if (selinux_conn_sid(sksec->sid, skb_sid, &peer_sid))
5128 return NF_DROP;
5129 secmark_perm = PACKET__SEND;
5130 } else {
5131 /* Locally generated packet, fetch the security label from the
5132 * associated socket. */
5133 struct sk_security_struct *sksec = sk->sk_security;
5134 peer_sid = sksec->sid;
5135 secmark_perm = PACKET__SEND;
5136 }
5137
5138 ad.type = LSM_AUDIT_DATA_NET;
5139 ad.u.net = &net;
5140 ad.u.net->netif = ifindex;
5141 ad.u.net->family = family;
5142 if (selinux_parse_skb(skb, &ad, &addrp, 0, NULL))
5143 return NF_DROP;
5144
5145 if (secmark_active)
5146 if (avc_has_perm(peer_sid, skb->secmark,
5147 SECCLASS_PACKET, secmark_perm, &ad))
5148 return NF_DROP_ERR(-ECONNREFUSED);
5149
5150 if (peerlbl_active) {
5151 u32 if_sid;
5152 u32 node_sid;
5153
5154 if (sel_netif_sid(dev_net(outdev), ifindex, &if_sid))
5155 return NF_DROP;
5156 if (avc_has_perm(peer_sid, if_sid,
5157 SECCLASS_NETIF, NETIF__EGRESS, &ad))
5158 return NF_DROP_ERR(-ECONNREFUSED);
5159
5160 if (sel_netnode_sid(addrp, family, &node_sid))
5161 return NF_DROP;
5162 if (avc_has_perm(peer_sid, node_sid,
5163 SECCLASS_NODE, NODE__SENDTO, &ad))
5164 return NF_DROP_ERR(-ECONNREFUSED);
5165 }
5166
5167 return NF_ACCEPT;
5168}
5169
5170static unsigned int selinux_ipv4_postroute(void *priv,
5171 struct sk_buff *skb,
5172 const struct nf_hook_state *state)
5173{
5174 return selinux_ip_postroute(skb, state->out, PF_INET);
5175}
5176
5177#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
5178static unsigned int selinux_ipv6_postroute(void *priv,
5179 struct sk_buff *skb,
5180 const struct nf_hook_state *state)
5181{
5182 return selinux_ip_postroute(skb, state->out, PF_INET6);
5183}
5184#endif /* IPV6 */
5185
5186#endif /* CONFIG_NETFILTER */
5187
5188static int selinux_netlink_send(struct sock *sk, struct sk_buff *skb)
5189{
5190 return selinux_nlmsg_perm(sk, skb);
5191}
5192
5193static int ipc_alloc_security(struct task_struct *task,
5194 struct kern_ipc_perm *perm,
5195 u16 sclass)
5196{
5197 struct ipc_security_struct *isec;
5198 u32 sid;
5199
5200 isec = kzalloc(sizeof(struct ipc_security_struct), GFP_KERNEL);
5201 if (!isec)
5202 return -ENOMEM;
5203
5204 sid = task_sid(task);
5205 isec->sclass = sclass;
5206 isec->sid = sid;
5207 perm->security = isec;
5208
5209 return 0;
5210}
5211
5212static void ipc_free_security(struct kern_ipc_perm *perm)
5213{
5214 struct ipc_security_struct *isec = perm->security;
5215 perm->security = NULL;
5216 kfree(isec);
5217}
5218
5219static int msg_msg_alloc_security(struct msg_msg *msg)
5220{
5221 struct msg_security_struct *msec;
5222
5223 msec = kzalloc(sizeof(struct msg_security_struct), GFP_KERNEL);
5224 if (!msec)
5225 return -ENOMEM;
5226
5227 msec->sid = SECINITSID_UNLABELED;
5228 msg->security = msec;
5229
5230 return 0;
5231}
5232
5233static void msg_msg_free_security(struct msg_msg *msg)
5234{
5235 struct msg_security_struct *msec = msg->security;
5236
5237 msg->security = NULL;
5238 kfree(msec);
5239}
5240
5241static int ipc_has_perm(struct kern_ipc_perm *ipc_perms,
5242 u32 perms)
5243{
5244 struct ipc_security_struct *isec;
5245 struct common_audit_data ad;
5246 u32 sid = current_sid();
5247
5248 isec = ipc_perms->security;
5249
5250 ad.type = LSM_AUDIT_DATA_IPC;
5251 ad.u.ipc_id = ipc_perms->key;
5252
5253 return avc_has_perm(sid, isec->sid, isec->sclass, perms, &ad);
5254}
5255
5256static int selinux_msg_msg_alloc_security(struct msg_msg *msg)
5257{
5258 return msg_msg_alloc_security(msg);
5259}
5260
5261static void selinux_msg_msg_free_security(struct msg_msg *msg)
5262{
5263 msg_msg_free_security(msg);
5264}
5265
5266/* message queue security operations */
5267static int selinux_msg_queue_alloc_security(struct msg_queue *msq)
5268{
5269 struct ipc_security_struct *isec;
5270 struct common_audit_data ad;
5271 u32 sid = current_sid();
5272 int rc;
5273
5274 rc = ipc_alloc_security(current, &msq->q_perm, SECCLASS_MSGQ);
5275 if (rc)
5276 return rc;
5277
5278 isec = msq->q_perm.security;
5279
5280 ad.type = LSM_AUDIT_DATA_IPC;
5281 ad.u.ipc_id = msq->q_perm.key;
5282
5283 rc = avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
5284 MSGQ__CREATE, &ad);
5285 if (rc) {
5286 ipc_free_security(&msq->q_perm);
5287 return rc;
5288 }
5289 return 0;
5290}
5291
5292static void selinux_msg_queue_free_security(struct msg_queue *msq)
5293{
5294 ipc_free_security(&msq->q_perm);
5295}
5296
5297static int selinux_msg_queue_associate(struct msg_queue *msq, int msqflg)
5298{
5299 struct ipc_security_struct *isec;
5300 struct common_audit_data ad;
5301 u32 sid = current_sid();
5302
5303 isec = msq->q_perm.security;
5304
5305 ad.type = LSM_AUDIT_DATA_IPC;
5306 ad.u.ipc_id = msq->q_perm.key;
5307
5308 return avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
5309 MSGQ__ASSOCIATE, &ad);
5310}
5311
5312static int selinux_msg_queue_msgctl(struct msg_queue *msq, int cmd)
5313{
5314 int err;
5315 int perms;
5316
5317 switch (cmd) {
5318 case IPC_INFO:
5319 case MSG_INFO:
5320 /* No specific object, just general system-wide information. */
5321 return task_has_system(current, SYSTEM__IPC_INFO);
5322 case IPC_STAT:
5323 case MSG_STAT:
5324 perms = MSGQ__GETATTR | MSGQ__ASSOCIATE;
5325 break;
5326 case IPC_SET:
5327 perms = MSGQ__SETATTR;
5328 break;
5329 case IPC_RMID:
5330 perms = MSGQ__DESTROY;
5331 break;
5332 default:
5333 return 0;
5334 }
5335
5336 err = ipc_has_perm(&msq->q_perm, perms);
5337 return err;
5338}
5339
5340static int selinux_msg_queue_msgsnd(struct msg_queue *msq, struct msg_msg *msg, int msqflg)
5341{
5342 struct ipc_security_struct *isec;
5343 struct msg_security_struct *msec;
5344 struct common_audit_data ad;
5345 u32 sid = current_sid();
5346 int rc;
5347
5348 isec = msq->q_perm.security;
5349 msec = msg->security;
5350
5351 /*
5352 * First time through, need to assign label to the message
5353 */
5354 if (msec->sid == SECINITSID_UNLABELED) {
5355 /*
5356 * Compute new sid based on current process and
5357 * message queue this message will be stored in
5358 */
5359 rc = security_transition_sid(sid, isec->sid, SECCLASS_MSG,
5360 NULL, &msec->sid);
5361 if (rc)
5362 return rc;
5363 }
5364
5365 ad.type = LSM_AUDIT_DATA_IPC;
5366 ad.u.ipc_id = msq->q_perm.key;
5367
5368 /* Can this process write to the queue? */
5369 rc = avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
5370 MSGQ__WRITE, &ad);
5371 if (!rc)
5372 /* Can this process send the message */
5373 rc = avc_has_perm(sid, msec->sid, SECCLASS_MSG,
5374 MSG__SEND, &ad);
5375 if (!rc)
5376 /* Can the message be put in the queue? */
5377 rc = avc_has_perm(msec->sid, isec->sid, SECCLASS_MSGQ,
5378 MSGQ__ENQUEUE, &ad);
5379
5380 return rc;
5381}
5382
5383static int selinux_msg_queue_msgrcv(struct msg_queue *msq, struct msg_msg *msg,
5384 struct task_struct *target,
5385 long type, int mode)
5386{
5387 struct ipc_security_struct *isec;
5388 struct msg_security_struct *msec;
5389 struct common_audit_data ad;
5390 u32 sid = task_sid(target);
5391 int rc;
5392
5393 isec = msq->q_perm.security;
5394 msec = msg->security;
5395
5396 ad.type = LSM_AUDIT_DATA_IPC;
5397 ad.u.ipc_id = msq->q_perm.key;
5398
5399 rc = avc_has_perm(sid, isec->sid,
5400 SECCLASS_MSGQ, MSGQ__READ, &ad);
5401 if (!rc)
5402 rc = avc_has_perm(sid, msec->sid,
5403 SECCLASS_MSG, MSG__RECEIVE, &ad);
5404 return rc;
5405}
5406
5407/* Shared Memory security operations */
5408static int selinux_shm_alloc_security(struct shmid_kernel *shp)
5409{
5410 struct ipc_security_struct *isec;
5411 struct common_audit_data ad;
5412 u32 sid = current_sid();
5413 int rc;
5414
5415 rc = ipc_alloc_security(current, &shp->shm_perm, SECCLASS_SHM);
5416 if (rc)
5417 return rc;
5418
5419 isec = shp->shm_perm.security;
5420
5421 ad.type = LSM_AUDIT_DATA_IPC;
5422 ad.u.ipc_id = shp->shm_perm.key;
5423
5424 rc = avc_has_perm(sid, isec->sid, SECCLASS_SHM,
5425 SHM__CREATE, &ad);
5426 if (rc) {
5427 ipc_free_security(&shp->shm_perm);
5428 return rc;
5429 }
5430 return 0;
5431}
5432
5433static void selinux_shm_free_security(struct shmid_kernel *shp)
5434{
5435 ipc_free_security(&shp->shm_perm);
5436}
5437
5438static int selinux_shm_associate(struct shmid_kernel *shp, int shmflg)
5439{
5440 struct ipc_security_struct *isec;
5441 struct common_audit_data ad;
5442 u32 sid = current_sid();
5443
5444 isec = shp->shm_perm.security;
5445
5446 ad.type = LSM_AUDIT_DATA_IPC;
5447 ad.u.ipc_id = shp->shm_perm.key;
5448
5449 return avc_has_perm(sid, isec->sid, SECCLASS_SHM,
5450 SHM__ASSOCIATE, &ad);
5451}
5452
5453/* Note, at this point, shp is locked down */
5454static int selinux_shm_shmctl(struct shmid_kernel *shp, int cmd)
5455{
5456 int perms;
5457 int err;
5458
5459 switch (cmd) {
5460 case IPC_INFO:
5461 case SHM_INFO:
5462 /* No specific object, just general system-wide information. */
5463 return task_has_system(current, SYSTEM__IPC_INFO);
5464 case IPC_STAT:
5465 case SHM_STAT:
5466 perms = SHM__GETATTR | SHM__ASSOCIATE;
5467 break;
5468 case IPC_SET:
5469 perms = SHM__SETATTR;
5470 break;
5471 case SHM_LOCK:
5472 case SHM_UNLOCK:
5473 perms = SHM__LOCK;
5474 break;
5475 case IPC_RMID:
5476 perms = SHM__DESTROY;
5477 break;
5478 default:
5479 return 0;
5480 }
5481
5482 err = ipc_has_perm(&shp->shm_perm, perms);
5483 return err;
5484}
5485
5486static int selinux_shm_shmat(struct shmid_kernel *shp,
5487 char __user *shmaddr, int shmflg)
5488{
5489 u32 perms;
5490
5491 if (shmflg & SHM_RDONLY)
5492 perms = SHM__READ;
5493 else
5494 perms = SHM__READ | SHM__WRITE;
5495
5496 return ipc_has_perm(&shp->shm_perm, perms);
5497}
5498
5499/* Semaphore security operations */
5500static int selinux_sem_alloc_security(struct sem_array *sma)
5501{
5502 struct ipc_security_struct *isec;
5503 struct common_audit_data ad;
5504 u32 sid = current_sid();
5505 int rc;
5506
5507 rc = ipc_alloc_security(current, &sma->sem_perm, SECCLASS_SEM);
5508 if (rc)
5509 return rc;
5510
5511 isec = sma->sem_perm.security;
5512
5513 ad.type = LSM_AUDIT_DATA_IPC;
5514 ad.u.ipc_id = sma->sem_perm.key;
5515
5516 rc = avc_has_perm(sid, isec->sid, SECCLASS_SEM,
5517 SEM__CREATE, &ad);
5518 if (rc) {
5519 ipc_free_security(&sma->sem_perm);
5520 return rc;
5521 }
5522 return 0;
5523}
5524
5525static void selinux_sem_free_security(struct sem_array *sma)
5526{
5527 ipc_free_security(&sma->sem_perm);
5528}
5529
5530static int selinux_sem_associate(struct sem_array *sma, int semflg)
5531{
5532 struct ipc_security_struct *isec;
5533 struct common_audit_data ad;
5534 u32 sid = current_sid();
5535
5536 isec = sma->sem_perm.security;
5537
5538 ad.type = LSM_AUDIT_DATA_IPC;
5539 ad.u.ipc_id = sma->sem_perm.key;
5540
5541 return avc_has_perm(sid, isec->sid, SECCLASS_SEM,
5542 SEM__ASSOCIATE, &ad);
5543}
5544
5545/* Note, at this point, sma is locked down */
5546static int selinux_sem_semctl(struct sem_array *sma, int cmd)
5547{
5548 int err;
5549 u32 perms;
5550
5551 switch (cmd) {
5552 case IPC_INFO:
5553 case SEM_INFO:
5554 /* No specific object, just general system-wide information. */
5555 return task_has_system(current, SYSTEM__IPC_INFO);
5556 case GETPID:
5557 case GETNCNT:
5558 case GETZCNT:
5559 perms = SEM__GETATTR;
5560 break;
5561 case GETVAL:
5562 case GETALL:
5563 perms = SEM__READ;
5564 break;
5565 case SETVAL:
5566 case SETALL:
5567 perms = SEM__WRITE;
5568 break;
5569 case IPC_RMID:
5570 perms = SEM__DESTROY;
5571 break;
5572 case IPC_SET:
5573 perms = SEM__SETATTR;
5574 break;
5575 case IPC_STAT:
5576 case SEM_STAT:
5577 perms = SEM__GETATTR | SEM__ASSOCIATE;
5578 break;
5579 default:
5580 return 0;
5581 }
5582
5583 err = ipc_has_perm(&sma->sem_perm, perms);
5584 return err;
5585}
5586
5587static int selinux_sem_semop(struct sem_array *sma,
5588 struct sembuf *sops, unsigned nsops, int alter)
5589{
5590 u32 perms;
5591
5592 if (alter)
5593 perms = SEM__READ | SEM__WRITE;
5594 else
5595 perms = SEM__READ;
5596
5597 return ipc_has_perm(&sma->sem_perm, perms);
5598}
5599
5600static int selinux_ipc_permission(struct kern_ipc_perm *ipcp, short flag)
5601{
5602 u32 av = 0;
5603
5604 av = 0;
5605 if (flag & S_IRUGO)
5606 av |= IPC__UNIX_READ;
5607 if (flag & S_IWUGO)
5608 av |= IPC__UNIX_WRITE;
5609
5610 if (av == 0)
5611 return 0;
5612
5613 return ipc_has_perm(ipcp, av);
5614}
5615
5616static void selinux_ipc_getsecid(struct kern_ipc_perm *ipcp, u32 *secid)
5617{
5618 struct ipc_security_struct *isec = ipcp->security;
5619 *secid = isec->sid;
5620}
5621
5622static void selinux_d_instantiate(struct dentry *dentry, struct inode *inode)
5623{
5624 if (inode)
5625 inode_doinit_with_dentry(inode, dentry);
5626}
5627
5628static int selinux_getprocattr(struct task_struct *p,
5629 char *name, char **value)
5630{
5631 const struct task_security_struct *__tsec;
5632 u32 sid;
5633 int error;
5634 unsigned len;
5635
5636 if (current != p) {
5637 error = current_has_perm(p, PROCESS__GETATTR);
5638 if (error)
5639 return error;
5640 }
5641
5642 rcu_read_lock();
5643 __tsec = __task_cred(p)->security;
5644
5645 if (!strcmp(name, "current"))
5646 sid = __tsec->sid;
5647 else if (!strcmp(name, "prev"))
5648 sid = __tsec->osid;
5649 else if (!strcmp(name, "exec"))
5650 sid = __tsec->exec_sid;
5651 else if (!strcmp(name, "fscreate"))
5652 sid = __tsec->create_sid;
5653 else if (!strcmp(name, "keycreate"))
5654 sid = __tsec->keycreate_sid;
5655 else if (!strcmp(name, "sockcreate"))
5656 sid = __tsec->sockcreate_sid;
5657 else
5658 goto invalid;
5659 rcu_read_unlock();
5660
5661 if (!sid)
5662 return 0;
5663
5664 error = security_sid_to_context(sid, value, &len);
5665 if (error)
5666 return error;
5667 return len;
5668
5669invalid:
5670 rcu_read_unlock();
5671 return -EINVAL;
5672}
5673
5674static int selinux_setprocattr(struct task_struct *p,
5675 char *name, void *value, size_t size)
5676{
5677 struct task_security_struct *tsec;
5678 struct task_struct *tracer;
5679 struct cred *new;
5680 u32 sid = 0, ptsid;
5681 int error;
5682 char *str = value;
5683
5684 if (current != p) {
5685 /* SELinux only allows a process to change its own
5686 security attributes. */
5687 return -EACCES;
5688 }
5689
5690 /*
5691 * Basic control over ability to set these attributes at all.
5692 * current == p, but we'll pass them separately in case the
5693 * above restriction is ever removed.
5694 */
5695 if (!strcmp(name, "exec"))
5696 error = current_has_perm(p, PROCESS__SETEXEC);
5697 else if (!strcmp(name, "fscreate"))
5698 error = current_has_perm(p, PROCESS__SETFSCREATE);
5699 else if (!strcmp(name, "keycreate"))
5700 error = current_has_perm(p, PROCESS__SETKEYCREATE);
5701 else if (!strcmp(name, "sockcreate"))
5702 error = current_has_perm(p, PROCESS__SETSOCKCREATE);
5703 else if (!strcmp(name, "current"))
5704 error = current_has_perm(p, PROCESS__SETCURRENT);
5705 else
5706 error = -EINVAL;
5707 if (error)
5708 return error;
5709
5710 /* Obtain a SID for the context, if one was specified. */
5711 if (size && str[1] && str[1] != '\n') {
5712 if (str[size-1] == '\n') {
5713 str[size-1] = 0;
5714 size--;
5715 }
5716 error = security_context_to_sid(value, size, &sid, GFP_KERNEL);
5717 if (error == -EINVAL && !strcmp(name, "fscreate")) {
5718 if (!capable(CAP_MAC_ADMIN)) {
5719 struct audit_buffer *ab;
5720 size_t audit_size;
5721
5722 /* We strip a nul only if it is at the end, otherwise the
5723 * context contains a nul and we should audit that */
5724 if (str[size - 1] == '\0')
5725 audit_size = size - 1;
5726 else
5727 audit_size = size;
5728 ab = audit_log_start(current->audit_context, GFP_ATOMIC, AUDIT_SELINUX_ERR);
5729 audit_log_format(ab, "op=fscreate invalid_context=");
5730 audit_log_n_untrustedstring(ab, value, audit_size);
5731 audit_log_end(ab);
5732
5733 return error;
5734 }
5735 error = security_context_to_sid_force(value, size,
5736 &sid);
5737 }
5738 if (error)
5739 return error;
5740 }
5741
5742 new = prepare_creds();
5743 if (!new)
5744 return -ENOMEM;
5745
5746 /* Permission checking based on the specified context is
5747 performed during the actual operation (execve,
5748 open/mkdir/...), when we know the full context of the
5749 operation. See selinux_bprm_set_creds for the execve
5750 checks and may_create for the file creation checks. The
5751 operation will then fail if the context is not permitted. */
5752 tsec = new->security;
5753 if (!strcmp(name, "exec")) {
5754 tsec->exec_sid = sid;
5755 } else if (!strcmp(name, "fscreate")) {
5756 tsec->create_sid = sid;
5757 } else if (!strcmp(name, "keycreate")) {
5758 error = may_create_key(sid, p);
5759 if (error)
5760 goto abort_change;
5761 tsec->keycreate_sid = sid;
5762 } else if (!strcmp(name, "sockcreate")) {
5763 tsec->sockcreate_sid = sid;
5764 } else if (!strcmp(name, "current")) {
5765 error = -EINVAL;
5766 if (sid == 0)
5767 goto abort_change;
5768
5769 /* Only allow single threaded processes to change context */
5770 error = -EPERM;
5771 if (!current_is_single_threaded()) {
5772 error = security_bounded_transition(tsec->sid, sid);
5773 if (error)
5774 goto abort_change;
5775 }
5776
5777 /* Check permissions for the transition. */
5778 error = avc_has_perm(tsec->sid, sid, SECCLASS_PROCESS,
5779 PROCESS__DYNTRANSITION, NULL);
5780 if (error)
5781 goto abort_change;
5782
5783 /* Check for ptracing, and update the task SID if ok.
5784 Otherwise, leave SID unchanged and fail. */
5785 ptsid = 0;
5786 rcu_read_lock();
5787 tracer = ptrace_parent(p);
5788 if (tracer)
5789 ptsid = task_sid(tracer);
5790 rcu_read_unlock();
5791
5792 if (tracer) {
5793 error = avc_has_perm(ptsid, sid, SECCLASS_PROCESS,
5794 PROCESS__PTRACE, NULL);
5795 if (error)
5796 goto abort_change;
5797 }
5798
5799 tsec->sid = sid;
5800 } else {
5801 error = -EINVAL;
5802 goto abort_change;
5803 }
5804
5805 commit_creds(new);
5806 return size;
5807
5808abort_change:
5809 abort_creds(new);
5810 return error;
5811}
5812
5813static int selinux_ismaclabel(const char *name)
5814{
5815 return (strcmp(name, XATTR_SELINUX_SUFFIX) == 0);
5816}
5817
5818static int selinux_secid_to_secctx(u32 secid, char **secdata, u32 *seclen)
5819{
5820 return security_sid_to_context(secid, secdata, seclen);
5821}
5822
5823static int selinux_secctx_to_secid(const char *secdata, u32 seclen, u32 *secid)
5824{
5825 return security_context_to_sid(secdata, seclen, secid, GFP_KERNEL);
5826}
5827
5828static void selinux_release_secctx(char *secdata, u32 seclen)
5829{
5830 kfree(secdata);
5831}
5832
5833static void selinux_inode_invalidate_secctx(struct inode *inode)
5834{
5835 struct inode_security_struct *isec = inode->i_security;
5836
5837 mutex_lock(&isec->lock);
5838 isec->initialized = LABEL_INVALID;
5839 mutex_unlock(&isec->lock);
5840}
5841
5842/*
5843 * called with inode->i_mutex locked
5844 */
5845static int selinux_inode_notifysecctx(struct inode *inode, void *ctx, u32 ctxlen)
5846{
5847 return selinux_inode_setsecurity(inode, XATTR_SELINUX_SUFFIX, ctx, ctxlen, 0);
5848}
5849
5850/*
5851 * called with inode->i_mutex locked
5852 */
5853static int selinux_inode_setsecctx(struct dentry *dentry, void *ctx, u32 ctxlen)
5854{
5855 return __vfs_setxattr_noperm(dentry, XATTR_NAME_SELINUX, ctx, ctxlen, 0);
5856}
5857
5858static int selinux_inode_getsecctx(struct inode *inode, void **ctx, u32 *ctxlen)
5859{
5860 int len = 0;
5861 len = selinux_inode_getsecurity(inode, XATTR_SELINUX_SUFFIX,
5862 ctx, true);
5863 if (len < 0)
5864 return len;
5865 *ctxlen = len;
5866 return 0;
5867}
5868#ifdef CONFIG_KEYS
5869
5870static int selinux_key_alloc(struct key *k, const struct cred *cred,
5871 unsigned long flags)
5872{
5873 const struct task_security_struct *tsec;
5874 struct key_security_struct *ksec;
5875
5876 ksec = kzalloc(sizeof(struct key_security_struct), GFP_KERNEL);
5877 if (!ksec)
5878 return -ENOMEM;
5879
5880 tsec = cred->security;
5881 if (tsec->keycreate_sid)
5882 ksec->sid = tsec->keycreate_sid;
5883 else
5884 ksec->sid = tsec->sid;
5885
5886 k->security = ksec;
5887 return 0;
5888}
5889
5890static void selinux_key_free(struct key *k)
5891{
5892 struct key_security_struct *ksec = k->security;
5893
5894 k->security = NULL;
5895 kfree(ksec);
5896}
5897
5898static int selinux_key_permission(key_ref_t key_ref,
5899 const struct cred *cred,
5900 unsigned perm)
5901{
5902 struct key *key;
5903 struct key_security_struct *ksec;
5904 u32 sid;
5905
5906 /* if no specific permissions are requested, we skip the
5907 permission check. No serious, additional covert channels
5908 appear to be created. */
5909 if (perm == 0)
5910 return 0;
5911
5912 sid = cred_sid(cred);
5913
5914 key = key_ref_to_ptr(key_ref);
5915 ksec = key->security;
5916
5917 return avc_has_perm(sid, ksec->sid, SECCLASS_KEY, perm, NULL);
5918}
5919
5920static int selinux_key_getsecurity(struct key *key, char **_buffer)
5921{
5922 struct key_security_struct *ksec = key->security;
5923 char *context = NULL;
5924 unsigned len;
5925 int rc;
5926
5927 rc = security_sid_to_context(ksec->sid, &context, &len);
5928 if (!rc)
5929 rc = len;
5930 *_buffer = context;
5931 return rc;
5932}
5933
5934#endif
5935
5936static struct security_hook_list selinux_hooks[] = {
5937 LSM_HOOK_INIT(binder_set_context_mgr, selinux_binder_set_context_mgr),
5938 LSM_HOOK_INIT(binder_transaction, selinux_binder_transaction),
5939 LSM_HOOK_INIT(binder_transfer_binder, selinux_binder_transfer_binder),
5940 LSM_HOOK_INIT(binder_transfer_file, selinux_binder_transfer_file),
5941
5942 LSM_HOOK_INIT(ptrace_access_check, selinux_ptrace_access_check),
5943 LSM_HOOK_INIT(ptrace_traceme, selinux_ptrace_traceme),
5944 LSM_HOOK_INIT(capget, selinux_capget),
5945 LSM_HOOK_INIT(capset, selinux_capset),
5946 LSM_HOOK_INIT(capable, selinux_capable),
5947 LSM_HOOK_INIT(quotactl, selinux_quotactl),
5948 LSM_HOOK_INIT(quota_on, selinux_quota_on),
5949 LSM_HOOK_INIT(syslog, selinux_syslog),
5950 LSM_HOOK_INIT(vm_enough_memory, selinux_vm_enough_memory),
5951
5952 LSM_HOOK_INIT(netlink_send, selinux_netlink_send),
5953
5954 LSM_HOOK_INIT(bprm_set_creds, selinux_bprm_set_creds),
5955 LSM_HOOK_INIT(bprm_committing_creds, selinux_bprm_committing_creds),
5956 LSM_HOOK_INIT(bprm_committed_creds, selinux_bprm_committed_creds),
5957 LSM_HOOK_INIT(bprm_secureexec, selinux_bprm_secureexec),
5958
5959 LSM_HOOK_INIT(sb_alloc_security, selinux_sb_alloc_security),
5960 LSM_HOOK_INIT(sb_free_security, selinux_sb_free_security),
5961 LSM_HOOK_INIT(sb_copy_data, selinux_sb_copy_data),
5962 LSM_HOOK_INIT(sb_remount, selinux_sb_remount),
5963 LSM_HOOK_INIT(sb_kern_mount, selinux_sb_kern_mount),
5964 LSM_HOOK_INIT(sb_show_options, selinux_sb_show_options),
5965 LSM_HOOK_INIT(sb_statfs, selinux_sb_statfs),
5966 LSM_HOOK_INIT(sb_mount, selinux_mount),
5967 LSM_HOOK_INIT(sb_umount, selinux_umount),
5968 LSM_HOOK_INIT(sb_set_mnt_opts, selinux_set_mnt_opts),
5969 LSM_HOOK_INIT(sb_clone_mnt_opts, selinux_sb_clone_mnt_opts),
5970 LSM_HOOK_INIT(sb_parse_opts_str, selinux_parse_opts_str),
5971
5972 LSM_HOOK_INIT(dentry_init_security, selinux_dentry_init_security),
5973
5974 LSM_HOOK_INIT(inode_alloc_security, selinux_inode_alloc_security),
5975 LSM_HOOK_INIT(inode_free_security, selinux_inode_free_security),
5976 LSM_HOOK_INIT(inode_init_security, selinux_inode_init_security),
5977 LSM_HOOK_INIT(inode_create, selinux_inode_create),
5978 LSM_HOOK_INIT(inode_link, selinux_inode_link),
5979 LSM_HOOK_INIT(inode_unlink, selinux_inode_unlink),
5980 LSM_HOOK_INIT(inode_symlink, selinux_inode_symlink),
5981 LSM_HOOK_INIT(inode_mkdir, selinux_inode_mkdir),
5982 LSM_HOOK_INIT(inode_rmdir, selinux_inode_rmdir),
5983 LSM_HOOK_INIT(inode_mknod, selinux_inode_mknod),
5984 LSM_HOOK_INIT(inode_rename, selinux_inode_rename),
5985 LSM_HOOK_INIT(inode_readlink, selinux_inode_readlink),
5986 LSM_HOOK_INIT(inode_follow_link, selinux_inode_follow_link),
5987 LSM_HOOK_INIT(inode_permission, selinux_inode_permission),
5988 LSM_HOOK_INIT(inode_setattr, selinux_inode_setattr),
5989 LSM_HOOK_INIT(inode_getattr, selinux_inode_getattr),
5990 LSM_HOOK_INIT(inode_setxattr, selinux_inode_setxattr),
5991 LSM_HOOK_INIT(inode_post_setxattr, selinux_inode_post_setxattr),
5992 LSM_HOOK_INIT(inode_getxattr, selinux_inode_getxattr),
5993 LSM_HOOK_INIT(inode_listxattr, selinux_inode_listxattr),
5994 LSM_HOOK_INIT(inode_removexattr, selinux_inode_removexattr),
5995 LSM_HOOK_INIT(inode_getsecurity, selinux_inode_getsecurity),
5996 LSM_HOOK_INIT(inode_setsecurity, selinux_inode_setsecurity),
5997 LSM_HOOK_INIT(inode_listsecurity, selinux_inode_listsecurity),
5998 LSM_HOOK_INIT(inode_getsecid, selinux_inode_getsecid),
5999
6000 LSM_HOOK_INIT(file_permission, selinux_file_permission),
6001 LSM_HOOK_INIT(file_alloc_security, selinux_file_alloc_security),
6002 LSM_HOOK_INIT(file_free_security, selinux_file_free_security),
6003 LSM_HOOK_INIT(file_ioctl, selinux_file_ioctl),
6004 LSM_HOOK_INIT(mmap_file, selinux_mmap_file),
6005 LSM_HOOK_INIT(mmap_addr, selinux_mmap_addr),
6006 LSM_HOOK_INIT(file_mprotect, selinux_file_mprotect),
6007 LSM_HOOK_INIT(file_lock, selinux_file_lock),
6008 LSM_HOOK_INIT(file_fcntl, selinux_file_fcntl),
6009 LSM_HOOK_INIT(file_set_fowner, selinux_file_set_fowner),
6010 LSM_HOOK_INIT(file_send_sigiotask, selinux_file_send_sigiotask),
6011 LSM_HOOK_INIT(file_receive, selinux_file_receive),
6012
6013 LSM_HOOK_INIT(file_open, selinux_file_open),
6014
6015 LSM_HOOK_INIT(task_create, selinux_task_create),
6016 LSM_HOOK_INIT(cred_alloc_blank, selinux_cred_alloc_blank),
6017 LSM_HOOK_INIT(cred_free, selinux_cred_free),
6018 LSM_HOOK_INIT(cred_prepare, selinux_cred_prepare),
6019 LSM_HOOK_INIT(cred_transfer, selinux_cred_transfer),
6020 LSM_HOOK_INIT(kernel_act_as, selinux_kernel_act_as),
6021 LSM_HOOK_INIT(kernel_create_files_as, selinux_kernel_create_files_as),
6022 LSM_HOOK_INIT(kernel_module_request, selinux_kernel_module_request),
6023 LSM_HOOK_INIT(task_setpgid, selinux_task_setpgid),
6024 LSM_HOOK_INIT(task_getpgid, selinux_task_getpgid),
6025 LSM_HOOK_INIT(task_getsid, selinux_task_getsid),
6026 LSM_HOOK_INIT(task_getsecid, selinux_task_getsecid),
6027 LSM_HOOK_INIT(task_setnice, selinux_task_setnice),
6028 LSM_HOOK_INIT(task_setioprio, selinux_task_setioprio),
6029 LSM_HOOK_INIT(task_getioprio, selinux_task_getioprio),
6030 LSM_HOOK_INIT(task_setrlimit, selinux_task_setrlimit),
6031 LSM_HOOK_INIT(task_setscheduler, selinux_task_setscheduler),
6032 LSM_HOOK_INIT(task_getscheduler, selinux_task_getscheduler),
6033 LSM_HOOK_INIT(task_movememory, selinux_task_movememory),
6034 LSM_HOOK_INIT(task_kill, selinux_task_kill),
6035 LSM_HOOK_INIT(task_wait, selinux_task_wait),
6036 LSM_HOOK_INIT(task_to_inode, selinux_task_to_inode),
6037
6038 LSM_HOOK_INIT(ipc_permission, selinux_ipc_permission),
6039 LSM_HOOK_INIT(ipc_getsecid, selinux_ipc_getsecid),
6040
6041 LSM_HOOK_INIT(msg_msg_alloc_security, selinux_msg_msg_alloc_security),
6042 LSM_HOOK_INIT(msg_msg_free_security, selinux_msg_msg_free_security),
6043
6044 LSM_HOOK_INIT(msg_queue_alloc_security,
6045 selinux_msg_queue_alloc_security),
6046 LSM_HOOK_INIT(msg_queue_free_security, selinux_msg_queue_free_security),
6047 LSM_HOOK_INIT(msg_queue_associate, selinux_msg_queue_associate),
6048 LSM_HOOK_INIT(msg_queue_msgctl, selinux_msg_queue_msgctl),
6049 LSM_HOOK_INIT(msg_queue_msgsnd, selinux_msg_queue_msgsnd),
6050 LSM_HOOK_INIT(msg_queue_msgrcv, selinux_msg_queue_msgrcv),
6051
6052 LSM_HOOK_INIT(shm_alloc_security, selinux_shm_alloc_security),
6053 LSM_HOOK_INIT(shm_free_security, selinux_shm_free_security),
6054 LSM_HOOK_INIT(shm_associate, selinux_shm_associate),
6055 LSM_HOOK_INIT(shm_shmctl, selinux_shm_shmctl),
6056 LSM_HOOK_INIT(shm_shmat, selinux_shm_shmat),
6057
6058 LSM_HOOK_INIT(sem_alloc_security, selinux_sem_alloc_security),
6059 LSM_HOOK_INIT(sem_free_security, selinux_sem_free_security),
6060 LSM_HOOK_INIT(sem_associate, selinux_sem_associate),
6061 LSM_HOOK_INIT(sem_semctl, selinux_sem_semctl),
6062 LSM_HOOK_INIT(sem_semop, selinux_sem_semop),
6063
6064 LSM_HOOK_INIT(d_instantiate, selinux_d_instantiate),
6065
6066 LSM_HOOK_INIT(getprocattr, selinux_getprocattr),
6067 LSM_HOOK_INIT(setprocattr, selinux_setprocattr),
6068
6069 LSM_HOOK_INIT(ismaclabel, selinux_ismaclabel),
6070 LSM_HOOK_INIT(secid_to_secctx, selinux_secid_to_secctx),
6071 LSM_HOOK_INIT(secctx_to_secid, selinux_secctx_to_secid),
6072 LSM_HOOK_INIT(release_secctx, selinux_release_secctx),
6073 LSM_HOOK_INIT(inode_invalidate_secctx, selinux_inode_invalidate_secctx),
6074 LSM_HOOK_INIT(inode_notifysecctx, selinux_inode_notifysecctx),
6075 LSM_HOOK_INIT(inode_setsecctx, selinux_inode_setsecctx),
6076 LSM_HOOK_INIT(inode_getsecctx, selinux_inode_getsecctx),
6077
6078 LSM_HOOK_INIT(unix_stream_connect, selinux_socket_unix_stream_connect),
6079 LSM_HOOK_INIT(unix_may_send, selinux_socket_unix_may_send),
6080
6081 LSM_HOOK_INIT(socket_create, selinux_socket_create),
6082 LSM_HOOK_INIT(socket_post_create, selinux_socket_post_create),
6083 LSM_HOOK_INIT(socket_bind, selinux_socket_bind),
6084 LSM_HOOK_INIT(socket_connect, selinux_socket_connect),
6085 LSM_HOOK_INIT(socket_listen, selinux_socket_listen),
6086 LSM_HOOK_INIT(socket_accept, selinux_socket_accept),
6087 LSM_HOOK_INIT(socket_sendmsg, selinux_socket_sendmsg),
6088 LSM_HOOK_INIT(socket_recvmsg, selinux_socket_recvmsg),
6089 LSM_HOOK_INIT(socket_getsockname, selinux_socket_getsockname),
6090 LSM_HOOK_INIT(socket_getpeername, selinux_socket_getpeername),
6091 LSM_HOOK_INIT(socket_getsockopt, selinux_socket_getsockopt),
6092 LSM_HOOK_INIT(socket_setsockopt, selinux_socket_setsockopt),
6093 LSM_HOOK_INIT(socket_shutdown, selinux_socket_shutdown),
6094 LSM_HOOK_INIT(socket_sock_rcv_skb, selinux_socket_sock_rcv_skb),
6095 LSM_HOOK_INIT(socket_getpeersec_stream,
6096 selinux_socket_getpeersec_stream),
6097 LSM_HOOK_INIT(socket_getpeersec_dgram, selinux_socket_getpeersec_dgram),
6098 LSM_HOOK_INIT(sk_alloc_security, selinux_sk_alloc_security),
6099 LSM_HOOK_INIT(sk_free_security, selinux_sk_free_security),
6100 LSM_HOOK_INIT(sk_clone_security, selinux_sk_clone_security),
6101 LSM_HOOK_INIT(sk_getsecid, selinux_sk_getsecid),
6102 LSM_HOOK_INIT(sock_graft, selinux_sock_graft),
6103 LSM_HOOK_INIT(inet_conn_request, selinux_inet_conn_request),
6104 LSM_HOOK_INIT(inet_csk_clone, selinux_inet_csk_clone),
6105 LSM_HOOK_INIT(inet_conn_established, selinux_inet_conn_established),
6106 LSM_HOOK_INIT(secmark_relabel_packet, selinux_secmark_relabel_packet),
6107 LSM_HOOK_INIT(secmark_refcount_inc, selinux_secmark_refcount_inc),
6108 LSM_HOOK_INIT(secmark_refcount_dec, selinux_secmark_refcount_dec),
6109 LSM_HOOK_INIT(req_classify_flow, selinux_req_classify_flow),
6110 LSM_HOOK_INIT(tun_dev_alloc_security, selinux_tun_dev_alloc_security),
6111 LSM_HOOK_INIT(tun_dev_free_security, selinux_tun_dev_free_security),
6112 LSM_HOOK_INIT(tun_dev_create, selinux_tun_dev_create),
6113 LSM_HOOK_INIT(tun_dev_attach_queue, selinux_tun_dev_attach_queue),
6114 LSM_HOOK_INIT(tun_dev_attach, selinux_tun_dev_attach),
6115 LSM_HOOK_INIT(tun_dev_open, selinux_tun_dev_open),
6116
6117#ifdef CONFIG_SECURITY_NETWORK_XFRM
6118 LSM_HOOK_INIT(xfrm_policy_alloc_security, selinux_xfrm_policy_alloc),
6119 LSM_HOOK_INIT(xfrm_policy_clone_security, selinux_xfrm_policy_clone),
6120 LSM_HOOK_INIT(xfrm_policy_free_security, selinux_xfrm_policy_free),
6121 LSM_HOOK_INIT(xfrm_policy_delete_security, selinux_xfrm_policy_delete),
6122 LSM_HOOK_INIT(xfrm_state_alloc, selinux_xfrm_state_alloc),
6123 LSM_HOOK_INIT(xfrm_state_alloc_acquire,
6124 selinux_xfrm_state_alloc_acquire),
6125 LSM_HOOK_INIT(xfrm_state_free_security, selinux_xfrm_state_free),
6126 LSM_HOOK_INIT(xfrm_state_delete_security, selinux_xfrm_state_delete),
6127 LSM_HOOK_INIT(xfrm_policy_lookup, selinux_xfrm_policy_lookup),
6128 LSM_HOOK_INIT(xfrm_state_pol_flow_match,
6129 selinux_xfrm_state_pol_flow_match),
6130 LSM_HOOK_INIT(xfrm_decode_session, selinux_xfrm_decode_session),
6131#endif
6132
6133#ifdef CONFIG_KEYS
6134 LSM_HOOK_INIT(key_alloc, selinux_key_alloc),
6135 LSM_HOOK_INIT(key_free, selinux_key_free),
6136 LSM_HOOK_INIT(key_permission, selinux_key_permission),
6137 LSM_HOOK_INIT(key_getsecurity, selinux_key_getsecurity),
6138#endif
6139
6140#ifdef CONFIG_AUDIT
6141 LSM_HOOK_INIT(audit_rule_init, selinux_audit_rule_init),
6142 LSM_HOOK_INIT(audit_rule_known, selinux_audit_rule_known),
6143 LSM_HOOK_INIT(audit_rule_match, selinux_audit_rule_match),
6144 LSM_HOOK_INIT(audit_rule_free, selinux_audit_rule_free),
6145#endif
6146};
6147
6148static __init int selinux_init(void)
6149{
6150 if (!security_module_enable("selinux")) {
6151 selinux_enabled = 0;
6152 return 0;
6153 }
6154
6155 if (!selinux_enabled) {
6156 printk(KERN_INFO "SELinux: Disabled at boot.\n");
6157 return 0;
6158 }
6159
6160 printk(KERN_INFO "SELinux: Initializing.\n");
6161
6162 /* Set the security state for the initial task. */
6163 cred_init_security();
6164
6165 default_noexec = !(VM_DATA_DEFAULT_FLAGS & VM_EXEC);
6166
6167 sel_inode_cache = kmem_cache_create("selinux_inode_security",
6168 sizeof(struct inode_security_struct),
6169 0, SLAB_PANIC, NULL);
6170 file_security_cache = kmem_cache_create("selinux_file_security",
6171 sizeof(struct file_security_struct),
6172 0, SLAB_PANIC, NULL);
6173 avc_init();
6174
6175 security_add_hooks(selinux_hooks, ARRAY_SIZE(selinux_hooks));
6176
6177 if (avc_add_callback(selinux_netcache_avc_callback, AVC_CALLBACK_RESET))
6178 panic("SELinux: Unable to register AVC netcache callback\n");
6179
6180 if (selinux_enforcing)
6181 printk(KERN_DEBUG "SELinux: Starting in enforcing mode\n");
6182 else
6183 printk(KERN_DEBUG "SELinux: Starting in permissive mode\n");
6184
6185 return 0;
6186}
6187
6188static void delayed_superblock_init(struct super_block *sb, void *unused)
6189{
6190 superblock_doinit(sb, NULL);
6191}
6192
6193void selinux_complete_init(void)
6194{
6195 printk(KERN_DEBUG "SELinux: Completing initialization.\n");
6196
6197 /* Set up any superblocks initialized prior to the policy load. */
6198 printk(KERN_DEBUG "SELinux: Setting up existing superblocks.\n");
6199 iterate_supers(delayed_superblock_init, NULL);
6200}
6201
6202/* SELinux requires early initialization in order to label
6203 all processes and objects when they are created. */
6204security_initcall(selinux_init);
6205
6206#if defined(CONFIG_NETFILTER)
6207
6208static struct nf_hook_ops selinux_nf_ops[] = {
6209 {
6210 .hook = selinux_ipv4_postroute,
6211 .pf = NFPROTO_IPV4,
6212 .hooknum = NF_INET_POST_ROUTING,
6213 .priority = NF_IP_PRI_SELINUX_LAST,
6214 },
6215 {
6216 .hook = selinux_ipv4_forward,
6217 .pf = NFPROTO_IPV4,
6218 .hooknum = NF_INET_FORWARD,
6219 .priority = NF_IP_PRI_SELINUX_FIRST,
6220 },
6221 {
6222 .hook = selinux_ipv4_output,
6223 .pf = NFPROTO_IPV4,
6224 .hooknum = NF_INET_LOCAL_OUT,
6225 .priority = NF_IP_PRI_SELINUX_FIRST,
6226 },
6227#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
6228 {
6229 .hook = selinux_ipv6_postroute,
6230 .pf = NFPROTO_IPV6,
6231 .hooknum = NF_INET_POST_ROUTING,
6232 .priority = NF_IP6_PRI_SELINUX_LAST,
6233 },
6234 {
6235 .hook = selinux_ipv6_forward,
6236 .pf = NFPROTO_IPV6,
6237 .hooknum = NF_INET_FORWARD,
6238 .priority = NF_IP6_PRI_SELINUX_FIRST,
6239 },
6240#endif /* IPV6 */
6241};
6242
6243static int __init selinux_nf_ip_init(void)
6244{
6245 int err;
6246
6247 if (!selinux_enabled)
6248 return 0;
6249
6250 printk(KERN_DEBUG "SELinux: Registering netfilter hooks\n");
6251
6252 err = nf_register_hooks(selinux_nf_ops, ARRAY_SIZE(selinux_nf_ops));
6253 if (err)
6254 panic("SELinux: nf_register_hooks: error %d\n", err);
6255
6256 return 0;
6257}
6258
6259__initcall(selinux_nf_ip_init);
6260
6261#ifdef CONFIG_SECURITY_SELINUX_DISABLE
6262static void selinux_nf_ip_exit(void)
6263{
6264 printk(KERN_DEBUG "SELinux: Unregistering netfilter hooks\n");
6265
6266 nf_unregister_hooks(selinux_nf_ops, ARRAY_SIZE(selinux_nf_ops));
6267}
6268#endif
6269
6270#else /* CONFIG_NETFILTER */
6271
6272#ifdef CONFIG_SECURITY_SELINUX_DISABLE
6273#define selinux_nf_ip_exit()
6274#endif
6275
6276#endif /* CONFIG_NETFILTER */
6277
6278#ifdef CONFIG_SECURITY_SELINUX_DISABLE
6279static int selinux_disabled;
6280
6281int selinux_disable(void)
6282{
6283 if (ss_initialized) {
6284 /* Not permitted after initial policy load. */
6285 return -EINVAL;
6286 }
6287
6288 if (selinux_disabled) {
6289 /* Only do this once. */
6290 return -EINVAL;
6291 }
6292
6293 printk(KERN_INFO "SELinux: Disabled at runtime.\n");
6294
6295 selinux_disabled = 1;
6296 selinux_enabled = 0;
6297
6298 security_delete_hooks(selinux_hooks, ARRAY_SIZE(selinux_hooks));
6299
6300 /* Try to destroy the avc node cache */
6301 avc_disable();
6302
6303 /* Unregister netfilter hooks. */
6304 selinux_nf_ip_exit();
6305
6306 /* Unregister selinuxfs. */
6307 exit_sel_fs();
6308
6309 return 0;
6310}
6311#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