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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/security.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/sock.h>
55#include <net/tcp.h> /* struct or_callable used in sock_rcv_skb */
56#include <net/inet_connection_sock.h>
57#include <net/net_namespace.h>
58#include <net/netlabel.h>
59#include <linux/uaccess.h>
60#include <asm/ioctls.h>
61#include <linux/atomic.h>
62#include <linux/bitops.h>
63#include <linux/interrupt.h>
64#include <linux/netdevice.h> /* for network interface checks */
65#include <net/netlink.h>
66#include <linux/tcp.h>
67#include <linux/udp.h>
68#include <linux/dccp.h>
69#include <linux/quota.h>
70#include <linux/un.h> /* for Unix socket types */
71#include <net/af_unix.h> /* for Unix socket types */
72#include <linux/parser.h>
73#include <linux/nfs_mount.h>
74#include <net/ipv6.h>
75#include <linux/hugetlb.h>
76#include <linux/personality.h>
77#include <linux/audit.h>
78#include <linux/string.h>
79#include <linux/selinux.h>
80#include <linux/mutex.h>
81#include <linux/posix-timers.h>
82#include <linux/syslog.h>
83#include <linux/user_namespace.h>
84#include <linux/export.h>
85#include <linux/msg.h>
86#include <linux/shm.h>
87
88#include "avc.h"
89#include "objsec.h"
90#include "netif.h"
91#include "netnode.h"
92#include "netport.h"
93#include "xfrm.h"
94#include "netlabel.h"
95#include "audit.h"
96#include "avc_ss.h"
97
98extern struct security_operations *security_ops;
99
100/* SECMARK reference count */
101static atomic_t selinux_secmark_refcount = ATOMIC_INIT(0);
102
103#ifdef CONFIG_SECURITY_SELINUX_DEVELOP
104int selinux_enforcing;
105
106static int __init enforcing_setup(char *str)
107{
108 unsigned long enforcing;
109 if (!kstrtoul(str, 0, &enforcing))
110 selinux_enforcing = enforcing ? 1 : 0;
111 return 1;
112}
113__setup("enforcing=", enforcing_setup);
114#endif
115
116#ifdef CONFIG_SECURITY_SELINUX_BOOTPARAM
117int selinux_enabled = CONFIG_SECURITY_SELINUX_BOOTPARAM_VALUE;
118
119static int __init selinux_enabled_setup(char *str)
120{
121 unsigned long enabled;
122 if (!kstrtoul(str, 0, &enabled))
123 selinux_enabled = enabled ? 1 : 0;
124 return 1;
125}
126__setup("selinux=", selinux_enabled_setup);
127#else
128int selinux_enabled = 1;
129#endif
130
131static struct kmem_cache *sel_inode_cache;
132
133/**
134 * selinux_secmark_enabled - Check to see if SECMARK is currently enabled
135 *
136 * Description:
137 * This function checks the SECMARK reference counter to see if any SECMARK
138 * targets are currently configured, if the reference counter is greater than
139 * zero SECMARK is considered to be enabled. Returns true (1) if SECMARK is
140 * enabled, false (0) if SECMARK is disabled. If the always_check_network
141 * policy capability is enabled, SECMARK is always considered enabled.
142 *
143 */
144static int selinux_secmark_enabled(void)
145{
146 return (selinux_policycap_alwaysnetwork || atomic_read(&selinux_secmark_refcount));
147}
148
149/**
150 * selinux_peerlbl_enabled - Check to see if peer labeling is currently enabled
151 *
152 * Description:
153 * This function checks if NetLabel or labeled IPSEC is enabled. Returns true
154 * (1) if any are enabled or false (0) if neither are enabled. If the
155 * always_check_network policy capability is enabled, peer labeling
156 * is always considered enabled.
157 *
158 */
159static int selinux_peerlbl_enabled(void)
160{
161 return (selinux_policycap_alwaysnetwork || netlbl_enabled() || selinux_xfrm_enabled());
162}
163
164/*
165 * initialise the security for the init task
166 */
167static void cred_init_security(void)
168{
169 struct cred *cred = (struct cred *) current->real_cred;
170 struct task_security_struct *tsec;
171
172 tsec = kzalloc(sizeof(struct task_security_struct), GFP_KERNEL);
173 if (!tsec)
174 panic("SELinux: Failed to initialize initial task.\n");
175
176 tsec->osid = tsec->sid = SECINITSID_KERNEL;
177 cred->security = tsec;
178}
179
180/*
181 * get the security ID of a set of credentials
182 */
183static inline u32 cred_sid(const struct cred *cred)
184{
185 const struct task_security_struct *tsec;
186
187 tsec = cred->security;
188 return tsec->sid;
189}
190
191/*
192 * get the objective security ID of a task
193 */
194static inline u32 task_sid(const struct task_struct *task)
195{
196 u32 sid;
197
198 rcu_read_lock();
199 sid = cred_sid(__task_cred(task));
200 rcu_read_unlock();
201 return sid;
202}
203
204/*
205 * get the subjective security ID of the current task
206 */
207static inline u32 current_sid(void)
208{
209 const struct task_security_struct *tsec = current_security();
210
211 return tsec->sid;
212}
213
214/* Allocate and free functions for each kind of security blob. */
215
216static int inode_alloc_security(struct inode *inode)
217{
218 struct inode_security_struct *isec;
219 u32 sid = current_sid();
220
221 isec = kmem_cache_zalloc(sel_inode_cache, GFP_NOFS);
222 if (!isec)
223 return -ENOMEM;
224
225 mutex_init(&isec->lock);
226 INIT_LIST_HEAD(&isec->list);
227 isec->inode = inode;
228 isec->sid = SECINITSID_UNLABELED;
229 isec->sclass = SECCLASS_FILE;
230 isec->task_sid = sid;
231 inode->i_security = isec;
232
233 return 0;
234}
235
236static void inode_free_rcu(struct rcu_head *head)
237{
238 struct inode_security_struct *isec;
239
240 isec = container_of(head, struct inode_security_struct, rcu);
241 kmem_cache_free(sel_inode_cache, isec);
242}
243
244static void inode_free_security(struct inode *inode)
245{
246 struct inode_security_struct *isec = inode->i_security;
247 struct superblock_security_struct *sbsec = inode->i_sb->s_security;
248
249 spin_lock(&sbsec->isec_lock);
250 if (!list_empty(&isec->list))
251 list_del_init(&isec->list);
252 spin_unlock(&sbsec->isec_lock);
253
254 /*
255 * The inode may still be referenced in a path walk and
256 * a call to selinux_inode_permission() can be made
257 * after inode_free_security() is called. Ideally, the VFS
258 * wouldn't do this, but fixing that is a much harder
259 * job. For now, simply free the i_security via RCU, and
260 * leave the current inode->i_security pointer intact.
261 * The inode will be freed after the RCU grace period too.
262 */
263 call_rcu(&isec->rcu, inode_free_rcu);
264}
265
266static int file_alloc_security(struct file *file)
267{
268 struct file_security_struct *fsec;
269 u32 sid = current_sid();
270
271 fsec = kzalloc(sizeof(struct file_security_struct), GFP_KERNEL);
272 if (!fsec)
273 return -ENOMEM;
274
275 fsec->sid = sid;
276 fsec->fown_sid = sid;
277 file->f_security = fsec;
278
279 return 0;
280}
281
282static void file_free_security(struct file *file)
283{
284 struct file_security_struct *fsec = file->f_security;
285 file->f_security = NULL;
286 kfree(fsec);
287}
288
289static int superblock_alloc_security(struct super_block *sb)
290{
291 struct superblock_security_struct *sbsec;
292
293 sbsec = kzalloc(sizeof(struct superblock_security_struct), GFP_KERNEL);
294 if (!sbsec)
295 return -ENOMEM;
296
297 mutex_init(&sbsec->lock);
298 INIT_LIST_HEAD(&sbsec->isec_head);
299 spin_lock_init(&sbsec->isec_lock);
300 sbsec->sb = sb;
301 sbsec->sid = SECINITSID_UNLABELED;
302 sbsec->def_sid = SECINITSID_FILE;
303 sbsec->mntpoint_sid = SECINITSID_UNLABELED;
304 sb->s_security = sbsec;
305
306 return 0;
307}
308
309static void superblock_free_security(struct super_block *sb)
310{
311 struct superblock_security_struct *sbsec = sb->s_security;
312 sb->s_security = NULL;
313 kfree(sbsec);
314}
315
316/* The file system's label must be initialized prior to use. */
317
318static const char *labeling_behaviors[7] = {
319 "uses xattr",
320 "uses transition SIDs",
321 "uses task SIDs",
322 "uses genfs_contexts",
323 "not configured for labeling",
324 "uses mountpoint labeling",
325 "uses native labeling",
326};
327
328static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dentry);
329
330static inline int inode_doinit(struct inode *inode)
331{
332 return inode_doinit_with_dentry(inode, NULL);
333}
334
335enum {
336 Opt_error = -1,
337 Opt_context = 1,
338 Opt_fscontext = 2,
339 Opt_defcontext = 3,
340 Opt_rootcontext = 4,
341 Opt_labelsupport = 5,
342 Opt_nextmntopt = 6,
343};
344
345#define NUM_SEL_MNT_OPTS (Opt_nextmntopt - 1)
346
347static const match_table_t tokens = {
348 {Opt_context, CONTEXT_STR "%s"},
349 {Opt_fscontext, FSCONTEXT_STR "%s"},
350 {Opt_defcontext, DEFCONTEXT_STR "%s"},
351 {Opt_rootcontext, ROOTCONTEXT_STR "%s"},
352 {Opt_labelsupport, LABELSUPP_STR},
353 {Opt_error, NULL},
354};
355
356#define SEL_MOUNT_FAIL_MSG "SELinux: duplicate or incompatible mount options\n"
357
358static int may_context_mount_sb_relabel(u32 sid,
359 struct superblock_security_struct *sbsec,
360 const struct cred *cred)
361{
362 const struct task_security_struct *tsec = cred->security;
363 int rc;
364
365 rc = avc_has_perm(tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM,
366 FILESYSTEM__RELABELFROM, NULL);
367 if (rc)
368 return rc;
369
370 rc = avc_has_perm(tsec->sid, sid, SECCLASS_FILESYSTEM,
371 FILESYSTEM__RELABELTO, NULL);
372 return rc;
373}
374
375static int may_context_mount_inode_relabel(u32 sid,
376 struct superblock_security_struct *sbsec,
377 const struct cred *cred)
378{
379 const struct task_security_struct *tsec = cred->security;
380 int rc;
381 rc = avc_has_perm(tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM,
382 FILESYSTEM__RELABELFROM, NULL);
383 if (rc)
384 return rc;
385
386 rc = avc_has_perm(sid, sbsec->sid, SECCLASS_FILESYSTEM,
387 FILESYSTEM__ASSOCIATE, NULL);
388 return rc;
389}
390
391static int selinux_is_sblabel_mnt(struct super_block *sb)
392{
393 struct superblock_security_struct *sbsec = sb->s_security;
394
395 if (sbsec->behavior == SECURITY_FS_USE_XATTR ||
396 sbsec->behavior == SECURITY_FS_USE_TRANS ||
397 sbsec->behavior == SECURITY_FS_USE_TASK)
398 return 1;
399
400 /* Special handling for sysfs. Is genfs but also has setxattr handler*/
401 if (strncmp(sb->s_type->name, "sysfs", sizeof("sysfs")) == 0)
402 return 1;
403
404 /*
405 * Special handling for rootfs. Is genfs but supports
406 * setting SELinux context on in-core inodes.
407 */
408 if (strncmp(sb->s_type->name, "rootfs", sizeof("rootfs")) == 0)
409 return 1;
410
411 return 0;
412}
413
414static int sb_finish_set_opts(struct super_block *sb)
415{
416 struct superblock_security_struct *sbsec = sb->s_security;
417 struct dentry *root = sb->s_root;
418 struct inode *root_inode = root->d_inode;
419 int rc = 0;
420
421 if (sbsec->behavior == SECURITY_FS_USE_XATTR) {
422 /* Make sure that the xattr handler exists and that no
423 error other than -ENODATA is returned by getxattr on
424 the root directory. -ENODATA is ok, as this may be
425 the first boot of the SELinux kernel before we have
426 assigned xattr values to the filesystem. */
427 if (!root_inode->i_op->getxattr) {
428 printk(KERN_WARNING "SELinux: (dev %s, type %s) has no "
429 "xattr support\n", sb->s_id, sb->s_type->name);
430 rc = -EOPNOTSUPP;
431 goto out;
432 }
433 rc = root_inode->i_op->getxattr(root, XATTR_NAME_SELINUX, NULL, 0);
434 if (rc < 0 && rc != -ENODATA) {
435 if (rc == -EOPNOTSUPP)
436 printk(KERN_WARNING "SELinux: (dev %s, type "
437 "%s) has no security xattr handler\n",
438 sb->s_id, sb->s_type->name);
439 else
440 printk(KERN_WARNING "SELinux: (dev %s, type "
441 "%s) getxattr errno %d\n", sb->s_id,
442 sb->s_type->name, -rc);
443 goto out;
444 }
445 }
446
447 if (sbsec->behavior > ARRAY_SIZE(labeling_behaviors))
448 printk(KERN_ERR "SELinux: initialized (dev %s, type %s), unknown behavior\n",
449 sb->s_id, sb->s_type->name);
450 else
451 printk(KERN_DEBUG "SELinux: initialized (dev %s, type %s), %s\n",
452 sb->s_id, sb->s_type->name,
453 labeling_behaviors[sbsec->behavior-1]);
454
455 sbsec->flags |= SE_SBINITIALIZED;
456 if (selinux_is_sblabel_mnt(sb))
457 sbsec->flags |= SBLABEL_MNT;
458
459 /* Initialize the root inode. */
460 rc = inode_doinit_with_dentry(root_inode, root);
461
462 /* Initialize any other inodes associated with the superblock, e.g.
463 inodes created prior to initial policy load or inodes created
464 during get_sb by a pseudo filesystem that directly
465 populates itself. */
466 spin_lock(&sbsec->isec_lock);
467next_inode:
468 if (!list_empty(&sbsec->isec_head)) {
469 struct inode_security_struct *isec =
470 list_entry(sbsec->isec_head.next,
471 struct inode_security_struct, list);
472 struct inode *inode = isec->inode;
473 spin_unlock(&sbsec->isec_lock);
474 inode = igrab(inode);
475 if (inode) {
476 if (!IS_PRIVATE(inode))
477 inode_doinit(inode);
478 iput(inode);
479 }
480 spin_lock(&sbsec->isec_lock);
481 list_del_init(&isec->list);
482 goto next_inode;
483 }
484 spin_unlock(&sbsec->isec_lock);
485out:
486 return rc;
487}
488
489/*
490 * This function should allow an FS to ask what it's mount security
491 * options were so it can use those later for submounts, displaying
492 * mount options, or whatever.
493 */
494static int selinux_get_mnt_opts(const struct super_block *sb,
495 struct security_mnt_opts *opts)
496{
497 int rc = 0, i;
498 struct superblock_security_struct *sbsec = sb->s_security;
499 char *context = NULL;
500 u32 len;
501 char tmp;
502
503 security_init_mnt_opts(opts);
504
505 if (!(sbsec->flags & SE_SBINITIALIZED))
506 return -EINVAL;
507
508 if (!ss_initialized)
509 return -EINVAL;
510
511 /* make sure we always check enough bits to cover the mask */
512 BUILD_BUG_ON(SE_MNTMASK >= (1 << NUM_SEL_MNT_OPTS));
513
514 tmp = sbsec->flags & SE_MNTMASK;
515 /* count the number of mount options for this sb */
516 for (i = 0; i < NUM_SEL_MNT_OPTS; i++) {
517 if (tmp & 0x01)
518 opts->num_mnt_opts++;
519 tmp >>= 1;
520 }
521 /* Check if the Label support flag is set */
522 if (sbsec->flags & SBLABEL_MNT)
523 opts->num_mnt_opts++;
524
525 opts->mnt_opts = kcalloc(opts->num_mnt_opts, sizeof(char *), GFP_ATOMIC);
526 if (!opts->mnt_opts) {
527 rc = -ENOMEM;
528 goto out_free;
529 }
530
531 opts->mnt_opts_flags = kcalloc(opts->num_mnt_opts, sizeof(int), GFP_ATOMIC);
532 if (!opts->mnt_opts_flags) {
533 rc = -ENOMEM;
534 goto out_free;
535 }
536
537 i = 0;
538 if (sbsec->flags & FSCONTEXT_MNT) {
539 rc = security_sid_to_context(sbsec->sid, &context, &len);
540 if (rc)
541 goto out_free;
542 opts->mnt_opts[i] = context;
543 opts->mnt_opts_flags[i++] = FSCONTEXT_MNT;
544 }
545 if (sbsec->flags & CONTEXT_MNT) {
546 rc = security_sid_to_context(sbsec->mntpoint_sid, &context, &len);
547 if (rc)
548 goto out_free;
549 opts->mnt_opts[i] = context;
550 opts->mnt_opts_flags[i++] = CONTEXT_MNT;
551 }
552 if (sbsec->flags & DEFCONTEXT_MNT) {
553 rc = security_sid_to_context(sbsec->def_sid, &context, &len);
554 if (rc)
555 goto out_free;
556 opts->mnt_opts[i] = context;
557 opts->mnt_opts_flags[i++] = DEFCONTEXT_MNT;
558 }
559 if (sbsec->flags & ROOTCONTEXT_MNT) {
560 struct inode *root = sbsec->sb->s_root->d_inode;
561 struct inode_security_struct *isec = root->i_security;
562
563 rc = security_sid_to_context(isec->sid, &context, &len);
564 if (rc)
565 goto out_free;
566 opts->mnt_opts[i] = context;
567 opts->mnt_opts_flags[i++] = ROOTCONTEXT_MNT;
568 }
569 if (sbsec->flags & SBLABEL_MNT) {
570 opts->mnt_opts[i] = NULL;
571 opts->mnt_opts_flags[i++] = SBLABEL_MNT;
572 }
573
574 BUG_ON(i != opts->num_mnt_opts);
575
576 return 0;
577
578out_free:
579 security_free_mnt_opts(opts);
580 return rc;
581}
582
583static int bad_option(struct superblock_security_struct *sbsec, char flag,
584 u32 old_sid, u32 new_sid)
585{
586 char mnt_flags = sbsec->flags & SE_MNTMASK;
587
588 /* check if the old mount command had the same options */
589 if (sbsec->flags & SE_SBINITIALIZED)
590 if (!(sbsec->flags & flag) ||
591 (old_sid != new_sid))
592 return 1;
593
594 /* check if we were passed the same options twice,
595 * aka someone passed context=a,context=b
596 */
597 if (!(sbsec->flags & SE_SBINITIALIZED))
598 if (mnt_flags & flag)
599 return 1;
600 return 0;
601}
602
603/*
604 * Allow filesystems with binary mount data to explicitly set mount point
605 * labeling information.
606 */
607static int selinux_set_mnt_opts(struct super_block *sb,
608 struct security_mnt_opts *opts,
609 unsigned long kern_flags,
610 unsigned long *set_kern_flags)
611{
612 const struct cred *cred = current_cred();
613 int rc = 0, i;
614 struct superblock_security_struct *sbsec = sb->s_security;
615 const char *name = sb->s_type->name;
616 struct inode *inode = sbsec->sb->s_root->d_inode;
617 struct inode_security_struct *root_isec = inode->i_security;
618 u32 fscontext_sid = 0, context_sid = 0, rootcontext_sid = 0;
619 u32 defcontext_sid = 0;
620 char **mount_options = opts->mnt_opts;
621 int *flags = opts->mnt_opts_flags;
622 int num_opts = opts->num_mnt_opts;
623
624 mutex_lock(&sbsec->lock);
625
626 if (!ss_initialized) {
627 if (!num_opts) {
628 /* Defer initialization until selinux_complete_init,
629 after the initial policy is loaded and the security
630 server is ready to handle calls. */
631 goto out;
632 }
633 rc = -EINVAL;
634 printk(KERN_WARNING "SELinux: Unable to set superblock options "
635 "before the security server is initialized\n");
636 goto out;
637 }
638 if (kern_flags && !set_kern_flags) {
639 /* Specifying internal flags without providing a place to
640 * place the results is not allowed */
641 rc = -EINVAL;
642 goto out;
643 }
644
645 /*
646 * Binary mount data FS will come through this function twice. Once
647 * from an explicit call and once from the generic calls from the vfs.
648 * Since the generic VFS calls will not contain any security mount data
649 * we need to skip the double mount verification.
650 *
651 * This does open a hole in which we will not notice if the first
652 * mount using this sb set explict options and a second mount using
653 * this sb does not set any security options. (The first options
654 * will be used for both mounts)
655 */
656 if ((sbsec->flags & SE_SBINITIALIZED) && (sb->s_type->fs_flags & FS_BINARY_MOUNTDATA)
657 && (num_opts == 0))
658 goto out;
659
660 /*
661 * parse the mount options, check if they are valid sids.
662 * also check if someone is trying to mount the same sb more
663 * than once with different security options.
664 */
665 for (i = 0; i < num_opts; i++) {
666 u32 sid;
667
668 if (flags[i] == SBLABEL_MNT)
669 continue;
670 rc = security_context_to_sid(mount_options[i],
671 strlen(mount_options[i]), &sid, GFP_KERNEL);
672 if (rc) {
673 printk(KERN_WARNING "SELinux: security_context_to_sid"
674 "(%s) failed for (dev %s, type %s) errno=%d\n",
675 mount_options[i], sb->s_id, name, rc);
676 goto out;
677 }
678 switch (flags[i]) {
679 case FSCONTEXT_MNT:
680 fscontext_sid = sid;
681
682 if (bad_option(sbsec, FSCONTEXT_MNT, sbsec->sid,
683 fscontext_sid))
684 goto out_double_mount;
685
686 sbsec->flags |= FSCONTEXT_MNT;
687 break;
688 case CONTEXT_MNT:
689 context_sid = sid;
690
691 if (bad_option(sbsec, CONTEXT_MNT, sbsec->mntpoint_sid,
692 context_sid))
693 goto out_double_mount;
694
695 sbsec->flags |= CONTEXT_MNT;
696 break;
697 case ROOTCONTEXT_MNT:
698 rootcontext_sid = sid;
699
700 if (bad_option(sbsec, ROOTCONTEXT_MNT, root_isec->sid,
701 rootcontext_sid))
702 goto out_double_mount;
703
704 sbsec->flags |= ROOTCONTEXT_MNT;
705
706 break;
707 case DEFCONTEXT_MNT:
708 defcontext_sid = sid;
709
710 if (bad_option(sbsec, DEFCONTEXT_MNT, sbsec->def_sid,
711 defcontext_sid))
712 goto out_double_mount;
713
714 sbsec->flags |= DEFCONTEXT_MNT;
715
716 break;
717 default:
718 rc = -EINVAL;
719 goto out;
720 }
721 }
722
723 if (sbsec->flags & SE_SBINITIALIZED) {
724 /* previously mounted with options, but not on this attempt? */
725 if ((sbsec->flags & SE_MNTMASK) && !num_opts)
726 goto out_double_mount;
727 rc = 0;
728 goto out;
729 }
730
731 if (strcmp(sb->s_type->name, "proc") == 0)
732 sbsec->flags |= SE_SBPROC;
733
734 if (!sbsec->behavior) {
735 /*
736 * Determine the labeling behavior to use for this
737 * filesystem type.
738 */
739 rc = security_fs_use(sb);
740 if (rc) {
741 printk(KERN_WARNING
742 "%s: security_fs_use(%s) returned %d\n",
743 __func__, sb->s_type->name, rc);
744 goto out;
745 }
746 }
747 /* sets the context of the superblock for the fs being mounted. */
748 if (fscontext_sid) {
749 rc = may_context_mount_sb_relabel(fscontext_sid, sbsec, cred);
750 if (rc)
751 goto out;
752
753 sbsec->sid = fscontext_sid;
754 }
755
756 /*
757 * Switch to using mount point labeling behavior.
758 * sets the label used on all file below the mountpoint, and will set
759 * the superblock context if not already set.
760 */
761 if (kern_flags & SECURITY_LSM_NATIVE_LABELS && !context_sid) {
762 sbsec->behavior = SECURITY_FS_USE_NATIVE;
763 *set_kern_flags |= SECURITY_LSM_NATIVE_LABELS;
764 }
765
766 if (context_sid) {
767 if (!fscontext_sid) {
768 rc = may_context_mount_sb_relabel(context_sid, sbsec,
769 cred);
770 if (rc)
771 goto out;
772 sbsec->sid = context_sid;
773 } else {
774 rc = may_context_mount_inode_relabel(context_sid, sbsec,
775 cred);
776 if (rc)
777 goto out;
778 }
779 if (!rootcontext_sid)
780 rootcontext_sid = context_sid;
781
782 sbsec->mntpoint_sid = context_sid;
783 sbsec->behavior = SECURITY_FS_USE_MNTPOINT;
784 }
785
786 if (rootcontext_sid) {
787 rc = may_context_mount_inode_relabel(rootcontext_sid, sbsec,
788 cred);
789 if (rc)
790 goto out;
791
792 root_isec->sid = rootcontext_sid;
793 root_isec->initialized = 1;
794 }
795
796 if (defcontext_sid) {
797 if (sbsec->behavior != SECURITY_FS_USE_XATTR &&
798 sbsec->behavior != SECURITY_FS_USE_NATIVE) {
799 rc = -EINVAL;
800 printk(KERN_WARNING "SELinux: defcontext option is "
801 "invalid for this filesystem type\n");
802 goto out;
803 }
804
805 if (defcontext_sid != sbsec->def_sid) {
806 rc = may_context_mount_inode_relabel(defcontext_sid,
807 sbsec, cred);
808 if (rc)
809 goto out;
810 }
811
812 sbsec->def_sid = defcontext_sid;
813 }
814
815 rc = sb_finish_set_opts(sb);
816out:
817 mutex_unlock(&sbsec->lock);
818 return rc;
819out_double_mount:
820 rc = -EINVAL;
821 printk(KERN_WARNING "SELinux: mount invalid. Same superblock, different "
822 "security settings for (dev %s, type %s)\n", sb->s_id, name);
823 goto out;
824}
825
826static int selinux_cmp_sb_context(const struct super_block *oldsb,
827 const struct super_block *newsb)
828{
829 struct superblock_security_struct *old = oldsb->s_security;
830 struct superblock_security_struct *new = newsb->s_security;
831 char oldflags = old->flags & SE_MNTMASK;
832 char newflags = new->flags & SE_MNTMASK;
833
834 if (oldflags != newflags)
835 goto mismatch;
836 if ((oldflags & FSCONTEXT_MNT) && old->sid != new->sid)
837 goto mismatch;
838 if ((oldflags & CONTEXT_MNT) && old->mntpoint_sid != new->mntpoint_sid)
839 goto mismatch;
840 if ((oldflags & DEFCONTEXT_MNT) && old->def_sid != new->def_sid)
841 goto mismatch;
842 if (oldflags & ROOTCONTEXT_MNT) {
843 struct inode_security_struct *oldroot = oldsb->s_root->d_inode->i_security;
844 struct inode_security_struct *newroot = newsb->s_root->d_inode->i_security;
845 if (oldroot->sid != newroot->sid)
846 goto mismatch;
847 }
848 return 0;
849mismatch:
850 printk(KERN_WARNING "SELinux: mount invalid. Same superblock, "
851 "different security settings for (dev %s, "
852 "type %s)\n", newsb->s_id, newsb->s_type->name);
853 return -EBUSY;
854}
855
856static int selinux_sb_clone_mnt_opts(const struct super_block *oldsb,
857 struct super_block *newsb)
858{
859 const struct superblock_security_struct *oldsbsec = oldsb->s_security;
860 struct superblock_security_struct *newsbsec = newsb->s_security;
861
862 int set_fscontext = (oldsbsec->flags & FSCONTEXT_MNT);
863 int set_context = (oldsbsec->flags & CONTEXT_MNT);
864 int set_rootcontext = (oldsbsec->flags & ROOTCONTEXT_MNT);
865
866 /*
867 * if the parent was able to be mounted it clearly had no special lsm
868 * mount options. thus we can safely deal with this superblock later
869 */
870 if (!ss_initialized)
871 return 0;
872
873 /* how can we clone if the old one wasn't set up?? */
874 BUG_ON(!(oldsbsec->flags & SE_SBINITIALIZED));
875
876 /* if fs is reusing a sb, make sure that the contexts match */
877 if (newsbsec->flags & SE_SBINITIALIZED)
878 return selinux_cmp_sb_context(oldsb, newsb);
879
880 mutex_lock(&newsbsec->lock);
881
882 newsbsec->flags = oldsbsec->flags;
883
884 newsbsec->sid = oldsbsec->sid;
885 newsbsec->def_sid = oldsbsec->def_sid;
886 newsbsec->behavior = oldsbsec->behavior;
887
888 if (set_context) {
889 u32 sid = oldsbsec->mntpoint_sid;
890
891 if (!set_fscontext)
892 newsbsec->sid = sid;
893 if (!set_rootcontext) {
894 struct inode *newinode = newsb->s_root->d_inode;
895 struct inode_security_struct *newisec = newinode->i_security;
896 newisec->sid = sid;
897 }
898 newsbsec->mntpoint_sid = sid;
899 }
900 if (set_rootcontext) {
901 const struct inode *oldinode = oldsb->s_root->d_inode;
902 const struct inode_security_struct *oldisec = oldinode->i_security;
903 struct inode *newinode = newsb->s_root->d_inode;
904 struct inode_security_struct *newisec = newinode->i_security;
905
906 newisec->sid = oldisec->sid;
907 }
908
909 sb_finish_set_opts(newsb);
910 mutex_unlock(&newsbsec->lock);
911 return 0;
912}
913
914static int selinux_parse_opts_str(char *options,
915 struct security_mnt_opts *opts)
916{
917 char *p;
918 char *context = NULL, *defcontext = NULL;
919 char *fscontext = NULL, *rootcontext = NULL;
920 int rc, num_mnt_opts = 0;
921
922 opts->num_mnt_opts = 0;
923
924 /* Standard string-based options. */
925 while ((p = strsep(&options, "|")) != NULL) {
926 int token;
927 substring_t args[MAX_OPT_ARGS];
928
929 if (!*p)
930 continue;
931
932 token = match_token(p, tokens, args);
933
934 switch (token) {
935 case Opt_context:
936 if (context || defcontext) {
937 rc = -EINVAL;
938 printk(KERN_WARNING SEL_MOUNT_FAIL_MSG);
939 goto out_err;
940 }
941 context = match_strdup(&args[0]);
942 if (!context) {
943 rc = -ENOMEM;
944 goto out_err;
945 }
946 break;
947
948 case Opt_fscontext:
949 if (fscontext) {
950 rc = -EINVAL;
951 printk(KERN_WARNING SEL_MOUNT_FAIL_MSG);
952 goto out_err;
953 }
954 fscontext = match_strdup(&args[0]);
955 if (!fscontext) {
956 rc = -ENOMEM;
957 goto out_err;
958 }
959 break;
960
961 case Opt_rootcontext:
962 if (rootcontext) {
963 rc = -EINVAL;
964 printk(KERN_WARNING SEL_MOUNT_FAIL_MSG);
965 goto out_err;
966 }
967 rootcontext = match_strdup(&args[0]);
968 if (!rootcontext) {
969 rc = -ENOMEM;
970 goto out_err;
971 }
972 break;
973
974 case Opt_defcontext:
975 if (context || defcontext) {
976 rc = -EINVAL;
977 printk(KERN_WARNING SEL_MOUNT_FAIL_MSG);
978 goto out_err;
979 }
980 defcontext = match_strdup(&args[0]);
981 if (!defcontext) {
982 rc = -ENOMEM;
983 goto out_err;
984 }
985 break;
986 case Opt_labelsupport:
987 break;
988 default:
989 rc = -EINVAL;
990 printk(KERN_WARNING "SELinux: unknown mount option\n");
991 goto out_err;
992
993 }
994 }
995
996 rc = -ENOMEM;
997 opts->mnt_opts = kcalloc(NUM_SEL_MNT_OPTS, sizeof(char *), GFP_ATOMIC);
998 if (!opts->mnt_opts)
999 goto out_err;
1000
1001 opts->mnt_opts_flags = kcalloc(NUM_SEL_MNT_OPTS, sizeof(int), GFP_ATOMIC);
1002 if (!opts->mnt_opts_flags) {
1003 kfree(opts->mnt_opts);
1004 goto out_err;
1005 }
1006
1007 if (fscontext) {
1008 opts->mnt_opts[num_mnt_opts] = fscontext;
1009 opts->mnt_opts_flags[num_mnt_opts++] = FSCONTEXT_MNT;
1010 }
1011 if (context) {
1012 opts->mnt_opts[num_mnt_opts] = context;
1013 opts->mnt_opts_flags[num_mnt_opts++] = CONTEXT_MNT;
1014 }
1015 if (rootcontext) {
1016 opts->mnt_opts[num_mnt_opts] = rootcontext;
1017 opts->mnt_opts_flags[num_mnt_opts++] = ROOTCONTEXT_MNT;
1018 }
1019 if (defcontext) {
1020 opts->mnt_opts[num_mnt_opts] = defcontext;
1021 opts->mnt_opts_flags[num_mnt_opts++] = DEFCONTEXT_MNT;
1022 }
1023
1024 opts->num_mnt_opts = num_mnt_opts;
1025 return 0;
1026
1027out_err:
1028 kfree(context);
1029 kfree(defcontext);
1030 kfree(fscontext);
1031 kfree(rootcontext);
1032 return rc;
1033}
1034/*
1035 * string mount options parsing and call set the sbsec
1036 */
1037static int superblock_doinit(struct super_block *sb, void *data)
1038{
1039 int rc = 0;
1040 char *options = data;
1041 struct security_mnt_opts opts;
1042
1043 security_init_mnt_opts(&opts);
1044
1045 if (!data)
1046 goto out;
1047
1048 BUG_ON(sb->s_type->fs_flags & FS_BINARY_MOUNTDATA);
1049
1050 rc = selinux_parse_opts_str(options, &opts);
1051 if (rc)
1052 goto out_err;
1053
1054out:
1055 rc = selinux_set_mnt_opts(sb, &opts, 0, NULL);
1056
1057out_err:
1058 security_free_mnt_opts(&opts);
1059 return rc;
1060}
1061
1062static void selinux_write_opts(struct seq_file *m,
1063 struct security_mnt_opts *opts)
1064{
1065 int i;
1066 char *prefix;
1067
1068 for (i = 0; i < opts->num_mnt_opts; i++) {
1069 char *has_comma;
1070
1071 if (opts->mnt_opts[i])
1072 has_comma = strchr(opts->mnt_opts[i], ',');
1073 else
1074 has_comma = NULL;
1075
1076 switch (opts->mnt_opts_flags[i]) {
1077 case CONTEXT_MNT:
1078 prefix = CONTEXT_STR;
1079 break;
1080 case FSCONTEXT_MNT:
1081 prefix = FSCONTEXT_STR;
1082 break;
1083 case ROOTCONTEXT_MNT:
1084 prefix = ROOTCONTEXT_STR;
1085 break;
1086 case DEFCONTEXT_MNT:
1087 prefix = DEFCONTEXT_STR;
1088 break;
1089 case SBLABEL_MNT:
1090 seq_putc(m, ',');
1091 seq_puts(m, LABELSUPP_STR);
1092 continue;
1093 default:
1094 BUG();
1095 return;
1096 };
1097 /* we need a comma before each option */
1098 seq_putc(m, ',');
1099 seq_puts(m, prefix);
1100 if (has_comma)
1101 seq_putc(m, '\"');
1102 seq_puts(m, opts->mnt_opts[i]);
1103 if (has_comma)
1104 seq_putc(m, '\"');
1105 }
1106}
1107
1108static int selinux_sb_show_options(struct seq_file *m, struct super_block *sb)
1109{
1110 struct security_mnt_opts opts;
1111 int rc;
1112
1113 rc = selinux_get_mnt_opts(sb, &opts);
1114 if (rc) {
1115 /* before policy load we may get EINVAL, don't show anything */
1116 if (rc == -EINVAL)
1117 rc = 0;
1118 return rc;
1119 }
1120
1121 selinux_write_opts(m, &opts);
1122
1123 security_free_mnt_opts(&opts);
1124
1125 return rc;
1126}
1127
1128static inline u16 inode_mode_to_security_class(umode_t mode)
1129{
1130 switch (mode & S_IFMT) {
1131 case S_IFSOCK:
1132 return SECCLASS_SOCK_FILE;
1133 case S_IFLNK:
1134 return SECCLASS_LNK_FILE;
1135 case S_IFREG:
1136 return SECCLASS_FILE;
1137 case S_IFBLK:
1138 return SECCLASS_BLK_FILE;
1139 case S_IFDIR:
1140 return SECCLASS_DIR;
1141 case S_IFCHR:
1142 return SECCLASS_CHR_FILE;
1143 case S_IFIFO:
1144 return SECCLASS_FIFO_FILE;
1145
1146 }
1147
1148 return SECCLASS_FILE;
1149}
1150
1151static inline int default_protocol_stream(int protocol)
1152{
1153 return (protocol == IPPROTO_IP || protocol == IPPROTO_TCP);
1154}
1155
1156static inline int default_protocol_dgram(int protocol)
1157{
1158 return (protocol == IPPROTO_IP || protocol == IPPROTO_UDP);
1159}
1160
1161static inline u16 socket_type_to_security_class(int family, int type, int protocol)
1162{
1163 switch (family) {
1164 case PF_UNIX:
1165 switch (type) {
1166 case SOCK_STREAM:
1167 case SOCK_SEQPACKET:
1168 return SECCLASS_UNIX_STREAM_SOCKET;
1169 case SOCK_DGRAM:
1170 return SECCLASS_UNIX_DGRAM_SOCKET;
1171 }
1172 break;
1173 case PF_INET:
1174 case PF_INET6:
1175 switch (type) {
1176 case SOCK_STREAM:
1177 if (default_protocol_stream(protocol))
1178 return SECCLASS_TCP_SOCKET;
1179 else
1180 return SECCLASS_RAWIP_SOCKET;
1181 case SOCK_DGRAM:
1182 if (default_protocol_dgram(protocol))
1183 return SECCLASS_UDP_SOCKET;
1184 else
1185 return SECCLASS_RAWIP_SOCKET;
1186 case SOCK_DCCP:
1187 return SECCLASS_DCCP_SOCKET;
1188 default:
1189 return SECCLASS_RAWIP_SOCKET;
1190 }
1191 break;
1192 case PF_NETLINK:
1193 switch (protocol) {
1194 case NETLINK_ROUTE:
1195 return SECCLASS_NETLINK_ROUTE_SOCKET;
1196 case NETLINK_FIREWALL:
1197 return SECCLASS_NETLINK_FIREWALL_SOCKET;
1198 case NETLINK_SOCK_DIAG:
1199 return SECCLASS_NETLINK_TCPDIAG_SOCKET;
1200 case NETLINK_NFLOG:
1201 return SECCLASS_NETLINK_NFLOG_SOCKET;
1202 case NETLINK_XFRM:
1203 return SECCLASS_NETLINK_XFRM_SOCKET;
1204 case NETLINK_SELINUX:
1205 return SECCLASS_NETLINK_SELINUX_SOCKET;
1206 case NETLINK_AUDIT:
1207 return SECCLASS_NETLINK_AUDIT_SOCKET;
1208 case NETLINK_IP6_FW:
1209 return SECCLASS_NETLINK_IP6FW_SOCKET;
1210 case NETLINK_DNRTMSG:
1211 return SECCLASS_NETLINK_DNRT_SOCKET;
1212 case NETLINK_KOBJECT_UEVENT:
1213 return SECCLASS_NETLINK_KOBJECT_UEVENT_SOCKET;
1214 default:
1215 return SECCLASS_NETLINK_SOCKET;
1216 }
1217 case PF_PACKET:
1218 return SECCLASS_PACKET_SOCKET;
1219 case PF_KEY:
1220 return SECCLASS_KEY_SOCKET;
1221 case PF_APPLETALK:
1222 return SECCLASS_APPLETALK_SOCKET;
1223 }
1224
1225 return SECCLASS_SOCKET;
1226}
1227
1228#ifdef CONFIG_PROC_FS
1229static int selinux_proc_get_sid(struct dentry *dentry,
1230 u16 tclass,
1231 u32 *sid)
1232{
1233 int rc;
1234 char *buffer, *path;
1235
1236 buffer = (char *)__get_free_page(GFP_KERNEL);
1237 if (!buffer)
1238 return -ENOMEM;
1239
1240 path = dentry_path_raw(dentry, buffer, PAGE_SIZE);
1241 if (IS_ERR(path))
1242 rc = PTR_ERR(path);
1243 else {
1244 /* each process gets a /proc/PID/ entry. Strip off the
1245 * PID part to get a valid selinux labeling.
1246 * e.g. /proc/1/net/rpc/nfs -> /net/rpc/nfs */
1247 while (path[1] >= '0' && path[1] <= '9') {
1248 path[1] = '/';
1249 path++;
1250 }
1251 rc = security_genfs_sid("proc", path, tclass, sid);
1252 }
1253 free_page((unsigned long)buffer);
1254 return rc;
1255}
1256#else
1257static int selinux_proc_get_sid(struct dentry *dentry,
1258 u16 tclass,
1259 u32 *sid)
1260{
1261 return -EINVAL;
1262}
1263#endif
1264
1265/* The inode's security attributes must be initialized before first use. */
1266static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dentry)
1267{
1268 struct superblock_security_struct *sbsec = NULL;
1269 struct inode_security_struct *isec = inode->i_security;
1270 u32 sid;
1271 struct dentry *dentry;
1272#define INITCONTEXTLEN 255
1273 char *context = NULL;
1274 unsigned len = 0;
1275 int rc = 0;
1276
1277 if (isec->initialized)
1278 goto out;
1279
1280 mutex_lock(&isec->lock);
1281 if (isec->initialized)
1282 goto out_unlock;
1283
1284 sbsec = inode->i_sb->s_security;
1285 if (!(sbsec->flags & SE_SBINITIALIZED)) {
1286 /* Defer initialization until selinux_complete_init,
1287 after the initial policy is loaded and the security
1288 server is ready to handle calls. */
1289 spin_lock(&sbsec->isec_lock);
1290 if (list_empty(&isec->list))
1291 list_add(&isec->list, &sbsec->isec_head);
1292 spin_unlock(&sbsec->isec_lock);
1293 goto out_unlock;
1294 }
1295
1296 switch (sbsec->behavior) {
1297 case SECURITY_FS_USE_NATIVE:
1298 break;
1299 case SECURITY_FS_USE_XATTR:
1300 if (!inode->i_op->getxattr) {
1301 isec->sid = sbsec->def_sid;
1302 break;
1303 }
1304
1305 /* Need a dentry, since the xattr API requires one.
1306 Life would be simpler if we could just pass the inode. */
1307 if (opt_dentry) {
1308 /* Called from d_instantiate or d_splice_alias. */
1309 dentry = dget(opt_dentry);
1310 } else {
1311 /* Called from selinux_complete_init, try to find a dentry. */
1312 dentry = d_find_alias(inode);
1313 }
1314 if (!dentry) {
1315 /*
1316 * this is can be hit on boot when a file is accessed
1317 * before the policy is loaded. When we load policy we
1318 * may find inodes that have no dentry on the
1319 * sbsec->isec_head list. No reason to complain as these
1320 * will get fixed up the next time we go through
1321 * inode_doinit with a dentry, before these inodes could
1322 * be used again by userspace.
1323 */
1324 goto out_unlock;
1325 }
1326
1327 len = INITCONTEXTLEN;
1328 context = kmalloc(len+1, GFP_NOFS);
1329 if (!context) {
1330 rc = -ENOMEM;
1331 dput(dentry);
1332 goto out_unlock;
1333 }
1334 context[len] = '\0';
1335 rc = inode->i_op->getxattr(dentry, XATTR_NAME_SELINUX,
1336 context, len);
1337 if (rc == -ERANGE) {
1338 kfree(context);
1339
1340 /* Need a larger buffer. Query for the right size. */
1341 rc = inode->i_op->getxattr(dentry, XATTR_NAME_SELINUX,
1342 NULL, 0);
1343 if (rc < 0) {
1344 dput(dentry);
1345 goto out_unlock;
1346 }
1347 len = rc;
1348 context = kmalloc(len+1, GFP_NOFS);
1349 if (!context) {
1350 rc = -ENOMEM;
1351 dput(dentry);
1352 goto out_unlock;
1353 }
1354 context[len] = '\0';
1355 rc = inode->i_op->getxattr(dentry,
1356 XATTR_NAME_SELINUX,
1357 context, len);
1358 }
1359 dput(dentry);
1360 if (rc < 0) {
1361 if (rc != -ENODATA) {
1362 printk(KERN_WARNING "SELinux: %s: getxattr returned "
1363 "%d for dev=%s ino=%ld\n", __func__,
1364 -rc, inode->i_sb->s_id, inode->i_ino);
1365 kfree(context);
1366 goto out_unlock;
1367 }
1368 /* Map ENODATA to the default file SID */
1369 sid = sbsec->def_sid;
1370 rc = 0;
1371 } else {
1372 rc = security_context_to_sid_default(context, rc, &sid,
1373 sbsec->def_sid,
1374 GFP_NOFS);
1375 if (rc) {
1376 char *dev = inode->i_sb->s_id;
1377 unsigned long ino = inode->i_ino;
1378
1379 if (rc == -EINVAL) {
1380 if (printk_ratelimit())
1381 printk(KERN_NOTICE "SELinux: inode=%lu on dev=%s was found to have an invalid "
1382 "context=%s. This indicates you may need to relabel the inode or the "
1383 "filesystem in question.\n", ino, dev, context);
1384 } else {
1385 printk(KERN_WARNING "SELinux: %s: context_to_sid(%s) "
1386 "returned %d for dev=%s ino=%ld\n",
1387 __func__, context, -rc, dev, ino);
1388 }
1389 kfree(context);
1390 /* Leave with the unlabeled SID */
1391 rc = 0;
1392 break;
1393 }
1394 }
1395 kfree(context);
1396 isec->sid = sid;
1397 break;
1398 case SECURITY_FS_USE_TASK:
1399 isec->sid = isec->task_sid;
1400 break;
1401 case SECURITY_FS_USE_TRANS:
1402 /* Default to the fs SID. */
1403 isec->sid = sbsec->sid;
1404
1405 /* Try to obtain a transition SID. */
1406 isec->sclass = inode_mode_to_security_class(inode->i_mode);
1407 rc = security_transition_sid(isec->task_sid, sbsec->sid,
1408 isec->sclass, NULL, &sid);
1409 if (rc)
1410 goto out_unlock;
1411 isec->sid = sid;
1412 break;
1413 case SECURITY_FS_USE_MNTPOINT:
1414 isec->sid = sbsec->mntpoint_sid;
1415 break;
1416 default:
1417 /* Default to the fs superblock SID. */
1418 isec->sid = sbsec->sid;
1419
1420 if ((sbsec->flags & SE_SBPROC) && !S_ISLNK(inode->i_mode)) {
1421 /* We must have a dentry to determine the label on
1422 * procfs inodes */
1423 if (opt_dentry)
1424 /* Called from d_instantiate or
1425 * d_splice_alias. */
1426 dentry = dget(opt_dentry);
1427 else
1428 /* Called from selinux_complete_init, try to
1429 * find a dentry. */
1430 dentry = d_find_alias(inode);
1431 /*
1432 * This can be hit on boot when a file is accessed
1433 * before the policy is loaded. When we load policy we
1434 * may find inodes that have no dentry on the
1435 * sbsec->isec_head list. No reason to complain as
1436 * these will get fixed up the next time we go through
1437 * inode_doinit() with a dentry, before these inodes
1438 * could be used again by userspace.
1439 */
1440 if (!dentry)
1441 goto out_unlock;
1442 isec->sclass = inode_mode_to_security_class(inode->i_mode);
1443 rc = selinux_proc_get_sid(dentry, isec->sclass, &sid);
1444 dput(dentry);
1445 if (rc)
1446 goto out_unlock;
1447 isec->sid = sid;
1448 }
1449 break;
1450 }
1451
1452 isec->initialized = 1;
1453
1454out_unlock:
1455 mutex_unlock(&isec->lock);
1456out:
1457 if (isec->sclass == SECCLASS_FILE)
1458 isec->sclass = inode_mode_to_security_class(inode->i_mode);
1459 return rc;
1460}
1461
1462/* Convert a Linux signal to an access vector. */
1463static inline u32 signal_to_av(int sig)
1464{
1465 u32 perm = 0;
1466
1467 switch (sig) {
1468 case SIGCHLD:
1469 /* Commonly granted from child to parent. */
1470 perm = PROCESS__SIGCHLD;
1471 break;
1472 case SIGKILL:
1473 /* Cannot be caught or ignored */
1474 perm = PROCESS__SIGKILL;
1475 break;
1476 case SIGSTOP:
1477 /* Cannot be caught or ignored */
1478 perm = PROCESS__SIGSTOP;
1479 break;
1480 default:
1481 /* All other signals. */
1482 perm = PROCESS__SIGNAL;
1483 break;
1484 }
1485
1486 return perm;
1487}
1488
1489/*
1490 * Check permission between a pair of credentials
1491 * fork check, ptrace check, etc.
1492 */
1493static int cred_has_perm(const struct cred *actor,
1494 const struct cred *target,
1495 u32 perms)
1496{
1497 u32 asid = cred_sid(actor), tsid = cred_sid(target);
1498
1499 return avc_has_perm(asid, tsid, SECCLASS_PROCESS, perms, NULL);
1500}
1501
1502/*
1503 * Check permission between a pair of tasks, e.g. signal checks,
1504 * fork check, ptrace check, etc.
1505 * tsk1 is the actor and tsk2 is the target
1506 * - this uses the default subjective creds of tsk1
1507 */
1508static int task_has_perm(const struct task_struct *tsk1,
1509 const struct task_struct *tsk2,
1510 u32 perms)
1511{
1512 const struct task_security_struct *__tsec1, *__tsec2;
1513 u32 sid1, sid2;
1514
1515 rcu_read_lock();
1516 __tsec1 = __task_cred(tsk1)->security; sid1 = __tsec1->sid;
1517 __tsec2 = __task_cred(tsk2)->security; sid2 = __tsec2->sid;
1518 rcu_read_unlock();
1519 return avc_has_perm(sid1, sid2, SECCLASS_PROCESS, perms, NULL);
1520}
1521
1522/*
1523 * Check permission between current and another task, e.g. signal checks,
1524 * fork check, ptrace check, etc.
1525 * current is the actor and tsk2 is the target
1526 * - this uses current's subjective creds
1527 */
1528static int current_has_perm(const struct task_struct *tsk,
1529 u32 perms)
1530{
1531 u32 sid, tsid;
1532
1533 sid = current_sid();
1534 tsid = task_sid(tsk);
1535 return avc_has_perm(sid, tsid, SECCLASS_PROCESS, perms, NULL);
1536}
1537
1538#if CAP_LAST_CAP > 63
1539#error Fix SELinux to handle capabilities > 63.
1540#endif
1541
1542/* Check whether a task is allowed to use a capability. */
1543static int cred_has_capability(const struct cred *cred,
1544 int cap, int audit)
1545{
1546 struct common_audit_data ad;
1547 struct av_decision avd;
1548 u16 sclass;
1549 u32 sid = cred_sid(cred);
1550 u32 av = CAP_TO_MASK(cap);
1551 int rc;
1552
1553 ad.type = LSM_AUDIT_DATA_CAP;
1554 ad.u.cap = cap;
1555
1556 switch (CAP_TO_INDEX(cap)) {
1557 case 0:
1558 sclass = SECCLASS_CAPABILITY;
1559 break;
1560 case 1:
1561 sclass = SECCLASS_CAPABILITY2;
1562 break;
1563 default:
1564 printk(KERN_ERR
1565 "SELinux: out of range capability %d\n", cap);
1566 BUG();
1567 return -EINVAL;
1568 }
1569
1570 rc = avc_has_perm_noaudit(sid, sid, sclass, av, 0, &avd);
1571 if (audit == SECURITY_CAP_AUDIT) {
1572 int rc2 = avc_audit(sid, sid, sclass, av, &avd, rc, &ad);
1573 if (rc2)
1574 return rc2;
1575 }
1576 return rc;
1577}
1578
1579/* Check whether a task is allowed to use a system operation. */
1580static int task_has_system(struct task_struct *tsk,
1581 u32 perms)
1582{
1583 u32 sid = task_sid(tsk);
1584
1585 return avc_has_perm(sid, SECINITSID_KERNEL,
1586 SECCLASS_SYSTEM, perms, NULL);
1587}
1588
1589/* Check whether a task has a particular permission to an inode.
1590 The 'adp' parameter is optional and allows other audit
1591 data to be passed (e.g. the dentry). */
1592static int inode_has_perm(const struct cred *cred,
1593 struct inode *inode,
1594 u32 perms,
1595 struct common_audit_data *adp)
1596{
1597 struct inode_security_struct *isec;
1598 u32 sid;
1599
1600 validate_creds(cred);
1601
1602 if (unlikely(IS_PRIVATE(inode)))
1603 return 0;
1604
1605 sid = cred_sid(cred);
1606 isec = inode->i_security;
1607
1608 return avc_has_perm(sid, isec->sid, isec->sclass, perms, adp);
1609}
1610
1611/* Same as inode_has_perm, but pass explicit audit data containing
1612 the dentry to help the auditing code to more easily generate the
1613 pathname if needed. */
1614static inline int dentry_has_perm(const struct cred *cred,
1615 struct dentry *dentry,
1616 u32 av)
1617{
1618 struct inode *inode = dentry->d_inode;
1619 struct common_audit_data ad;
1620
1621 ad.type = LSM_AUDIT_DATA_DENTRY;
1622 ad.u.dentry = dentry;
1623 return inode_has_perm(cred, inode, av, &ad);
1624}
1625
1626/* Same as inode_has_perm, but pass explicit audit data containing
1627 the path to help the auditing code to more easily generate the
1628 pathname if needed. */
1629static inline int path_has_perm(const struct cred *cred,
1630 struct path *path,
1631 u32 av)
1632{
1633 struct inode *inode = path->dentry->d_inode;
1634 struct common_audit_data ad;
1635
1636 ad.type = LSM_AUDIT_DATA_PATH;
1637 ad.u.path = *path;
1638 return inode_has_perm(cred, inode, av, &ad);
1639}
1640
1641/* Same as path_has_perm, but uses the inode from the file struct. */
1642static inline int file_path_has_perm(const struct cred *cred,
1643 struct file *file,
1644 u32 av)
1645{
1646 struct common_audit_data ad;
1647
1648 ad.type = LSM_AUDIT_DATA_PATH;
1649 ad.u.path = file->f_path;
1650 return inode_has_perm(cred, file_inode(file), av, &ad);
1651}
1652
1653/* Check whether a task can use an open file descriptor to
1654 access an inode in a given way. Check access to the
1655 descriptor itself, and then use dentry_has_perm to
1656 check a particular permission to the file.
1657 Access to the descriptor is implicitly granted if it
1658 has the same SID as the process. If av is zero, then
1659 access to the file is not checked, e.g. for cases
1660 where only the descriptor is affected like seek. */
1661static int file_has_perm(const struct cred *cred,
1662 struct file *file,
1663 u32 av)
1664{
1665 struct file_security_struct *fsec = file->f_security;
1666 struct inode *inode = file_inode(file);
1667 struct common_audit_data ad;
1668 u32 sid = cred_sid(cred);
1669 int rc;
1670
1671 ad.type = LSM_AUDIT_DATA_PATH;
1672 ad.u.path = file->f_path;
1673
1674 if (sid != fsec->sid) {
1675 rc = avc_has_perm(sid, fsec->sid,
1676 SECCLASS_FD,
1677 FD__USE,
1678 &ad);
1679 if (rc)
1680 goto out;
1681 }
1682
1683 /* av is zero if only checking access to the descriptor. */
1684 rc = 0;
1685 if (av)
1686 rc = inode_has_perm(cred, inode, av, &ad);
1687
1688out:
1689 return rc;
1690}
1691
1692/* Check whether a task can create a file. */
1693static int may_create(struct inode *dir,
1694 struct dentry *dentry,
1695 u16 tclass)
1696{
1697 const struct task_security_struct *tsec = current_security();
1698 struct inode_security_struct *dsec;
1699 struct superblock_security_struct *sbsec;
1700 u32 sid, newsid;
1701 struct common_audit_data ad;
1702 int rc;
1703
1704 dsec = dir->i_security;
1705 sbsec = dir->i_sb->s_security;
1706
1707 sid = tsec->sid;
1708 newsid = tsec->create_sid;
1709
1710 ad.type = LSM_AUDIT_DATA_DENTRY;
1711 ad.u.dentry = dentry;
1712
1713 rc = avc_has_perm(sid, dsec->sid, SECCLASS_DIR,
1714 DIR__ADD_NAME | DIR__SEARCH,
1715 &ad);
1716 if (rc)
1717 return rc;
1718
1719 if (!newsid || !(sbsec->flags & SBLABEL_MNT)) {
1720 rc = security_transition_sid(sid, dsec->sid, tclass,
1721 &dentry->d_name, &newsid);
1722 if (rc)
1723 return rc;
1724 }
1725
1726 rc = avc_has_perm(sid, newsid, tclass, FILE__CREATE, &ad);
1727 if (rc)
1728 return rc;
1729
1730 return avc_has_perm(newsid, sbsec->sid,
1731 SECCLASS_FILESYSTEM,
1732 FILESYSTEM__ASSOCIATE, &ad);
1733}
1734
1735/* Check whether a task can create a key. */
1736static int may_create_key(u32 ksid,
1737 struct task_struct *ctx)
1738{
1739 u32 sid = task_sid(ctx);
1740
1741 return avc_has_perm(sid, ksid, SECCLASS_KEY, KEY__CREATE, NULL);
1742}
1743
1744#define MAY_LINK 0
1745#define MAY_UNLINK 1
1746#define MAY_RMDIR 2
1747
1748/* Check whether a task can link, unlink, or rmdir a file/directory. */
1749static int may_link(struct inode *dir,
1750 struct dentry *dentry,
1751 int kind)
1752
1753{
1754 struct inode_security_struct *dsec, *isec;
1755 struct common_audit_data ad;
1756 u32 sid = current_sid();
1757 u32 av;
1758 int rc;
1759
1760 dsec = dir->i_security;
1761 isec = dentry->d_inode->i_security;
1762
1763 ad.type = LSM_AUDIT_DATA_DENTRY;
1764 ad.u.dentry = dentry;
1765
1766 av = DIR__SEARCH;
1767 av |= (kind ? DIR__REMOVE_NAME : DIR__ADD_NAME);
1768 rc = avc_has_perm(sid, dsec->sid, SECCLASS_DIR, av, &ad);
1769 if (rc)
1770 return rc;
1771
1772 switch (kind) {
1773 case MAY_LINK:
1774 av = FILE__LINK;
1775 break;
1776 case MAY_UNLINK:
1777 av = FILE__UNLINK;
1778 break;
1779 case MAY_RMDIR:
1780 av = DIR__RMDIR;
1781 break;
1782 default:
1783 printk(KERN_WARNING "SELinux: %s: unrecognized kind %d\n",
1784 __func__, kind);
1785 return 0;
1786 }
1787
1788 rc = avc_has_perm(sid, isec->sid, isec->sclass, av, &ad);
1789 return rc;
1790}
1791
1792static inline int may_rename(struct inode *old_dir,
1793 struct dentry *old_dentry,
1794 struct inode *new_dir,
1795 struct dentry *new_dentry)
1796{
1797 struct inode_security_struct *old_dsec, *new_dsec, *old_isec, *new_isec;
1798 struct common_audit_data ad;
1799 u32 sid = current_sid();
1800 u32 av;
1801 int old_is_dir, new_is_dir;
1802 int rc;
1803
1804 old_dsec = old_dir->i_security;
1805 old_isec = old_dentry->d_inode->i_security;
1806 old_is_dir = S_ISDIR(old_dentry->d_inode->i_mode);
1807 new_dsec = new_dir->i_security;
1808
1809 ad.type = LSM_AUDIT_DATA_DENTRY;
1810
1811 ad.u.dentry = old_dentry;
1812 rc = avc_has_perm(sid, old_dsec->sid, SECCLASS_DIR,
1813 DIR__REMOVE_NAME | DIR__SEARCH, &ad);
1814 if (rc)
1815 return rc;
1816 rc = avc_has_perm(sid, old_isec->sid,
1817 old_isec->sclass, FILE__RENAME, &ad);
1818 if (rc)
1819 return rc;
1820 if (old_is_dir && new_dir != old_dir) {
1821 rc = avc_has_perm(sid, old_isec->sid,
1822 old_isec->sclass, DIR__REPARENT, &ad);
1823 if (rc)
1824 return rc;
1825 }
1826
1827 ad.u.dentry = new_dentry;
1828 av = DIR__ADD_NAME | DIR__SEARCH;
1829 if (new_dentry->d_inode)
1830 av |= DIR__REMOVE_NAME;
1831 rc = avc_has_perm(sid, new_dsec->sid, SECCLASS_DIR, av, &ad);
1832 if (rc)
1833 return rc;
1834 if (new_dentry->d_inode) {
1835 new_isec = new_dentry->d_inode->i_security;
1836 new_is_dir = S_ISDIR(new_dentry->d_inode->i_mode);
1837 rc = avc_has_perm(sid, new_isec->sid,
1838 new_isec->sclass,
1839 (new_is_dir ? DIR__RMDIR : FILE__UNLINK), &ad);
1840 if (rc)
1841 return rc;
1842 }
1843
1844 return 0;
1845}
1846
1847/* Check whether a task can perform a filesystem operation. */
1848static int superblock_has_perm(const struct cred *cred,
1849 struct super_block *sb,
1850 u32 perms,
1851 struct common_audit_data *ad)
1852{
1853 struct superblock_security_struct *sbsec;
1854 u32 sid = cred_sid(cred);
1855
1856 sbsec = sb->s_security;
1857 return avc_has_perm(sid, sbsec->sid, SECCLASS_FILESYSTEM, perms, ad);
1858}
1859
1860/* Convert a Linux mode and permission mask to an access vector. */
1861static inline u32 file_mask_to_av(int mode, int mask)
1862{
1863 u32 av = 0;
1864
1865 if (!S_ISDIR(mode)) {
1866 if (mask & MAY_EXEC)
1867 av |= FILE__EXECUTE;
1868 if (mask & MAY_READ)
1869 av |= FILE__READ;
1870
1871 if (mask & MAY_APPEND)
1872 av |= FILE__APPEND;
1873 else if (mask & MAY_WRITE)
1874 av |= FILE__WRITE;
1875
1876 } else {
1877 if (mask & MAY_EXEC)
1878 av |= DIR__SEARCH;
1879 if (mask & MAY_WRITE)
1880 av |= DIR__WRITE;
1881 if (mask & MAY_READ)
1882 av |= DIR__READ;
1883 }
1884
1885 return av;
1886}
1887
1888/* Convert a Linux file to an access vector. */
1889static inline u32 file_to_av(struct file *file)
1890{
1891 u32 av = 0;
1892
1893 if (file->f_mode & FMODE_READ)
1894 av |= FILE__READ;
1895 if (file->f_mode & FMODE_WRITE) {
1896 if (file->f_flags & O_APPEND)
1897 av |= FILE__APPEND;
1898 else
1899 av |= FILE__WRITE;
1900 }
1901 if (!av) {
1902 /*
1903 * Special file opened with flags 3 for ioctl-only use.
1904 */
1905 av = FILE__IOCTL;
1906 }
1907
1908 return av;
1909}
1910
1911/*
1912 * Convert a file to an access vector and include the correct open
1913 * open permission.
1914 */
1915static inline u32 open_file_to_av(struct file *file)
1916{
1917 u32 av = file_to_av(file);
1918
1919 if (selinux_policycap_openperm)
1920 av |= FILE__OPEN;
1921
1922 return av;
1923}
1924
1925/* Hook functions begin here. */
1926
1927static int selinux_ptrace_access_check(struct task_struct *child,
1928 unsigned int mode)
1929{
1930 int rc;
1931
1932 rc = cap_ptrace_access_check(child, mode);
1933 if (rc)
1934 return rc;
1935
1936 if (mode & PTRACE_MODE_READ) {
1937 u32 sid = current_sid();
1938 u32 csid = task_sid(child);
1939 return avc_has_perm(sid, csid, SECCLASS_FILE, FILE__READ, NULL);
1940 }
1941
1942 return current_has_perm(child, PROCESS__PTRACE);
1943}
1944
1945static int selinux_ptrace_traceme(struct task_struct *parent)
1946{
1947 int rc;
1948
1949 rc = cap_ptrace_traceme(parent);
1950 if (rc)
1951 return rc;
1952
1953 return task_has_perm(parent, current, PROCESS__PTRACE);
1954}
1955
1956static int selinux_capget(struct task_struct *target, kernel_cap_t *effective,
1957 kernel_cap_t *inheritable, kernel_cap_t *permitted)
1958{
1959 int error;
1960
1961 error = current_has_perm(target, PROCESS__GETCAP);
1962 if (error)
1963 return error;
1964
1965 return cap_capget(target, effective, inheritable, permitted);
1966}
1967
1968static int selinux_capset(struct cred *new, const struct cred *old,
1969 const kernel_cap_t *effective,
1970 const kernel_cap_t *inheritable,
1971 const kernel_cap_t *permitted)
1972{
1973 int error;
1974
1975 error = cap_capset(new, old,
1976 effective, inheritable, permitted);
1977 if (error)
1978 return error;
1979
1980 return cred_has_perm(old, new, PROCESS__SETCAP);
1981}
1982
1983/*
1984 * (This comment used to live with the selinux_task_setuid hook,
1985 * which was removed).
1986 *
1987 * Since setuid only affects the current process, and since the SELinux
1988 * controls are not based on the Linux identity attributes, SELinux does not
1989 * need to control this operation. However, SELinux does control the use of
1990 * the CAP_SETUID and CAP_SETGID capabilities using the capable hook.
1991 */
1992
1993static int selinux_capable(const struct cred *cred, struct user_namespace *ns,
1994 int cap, int audit)
1995{
1996 int rc;
1997
1998 rc = cap_capable(cred, ns, cap, audit);
1999 if (rc)
2000 return rc;
2001
2002 return cred_has_capability(cred, cap, audit);
2003}
2004
2005static int selinux_quotactl(int cmds, int type, int id, struct super_block *sb)
2006{
2007 const struct cred *cred = current_cred();
2008 int rc = 0;
2009
2010 if (!sb)
2011 return 0;
2012
2013 switch (cmds) {
2014 case Q_SYNC:
2015 case Q_QUOTAON:
2016 case Q_QUOTAOFF:
2017 case Q_SETINFO:
2018 case Q_SETQUOTA:
2019 rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAMOD, NULL);
2020 break;
2021 case Q_GETFMT:
2022 case Q_GETINFO:
2023 case Q_GETQUOTA:
2024 rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAGET, NULL);
2025 break;
2026 default:
2027 rc = 0; /* let the kernel handle invalid cmds */
2028 break;
2029 }
2030 return rc;
2031}
2032
2033static int selinux_quota_on(struct dentry *dentry)
2034{
2035 const struct cred *cred = current_cred();
2036
2037 return dentry_has_perm(cred, dentry, FILE__QUOTAON);
2038}
2039
2040static int selinux_syslog(int type)
2041{
2042 int rc;
2043
2044 switch (type) {
2045 case SYSLOG_ACTION_READ_ALL: /* Read last kernel messages */
2046 case SYSLOG_ACTION_SIZE_BUFFER: /* Return size of the log buffer */
2047 rc = task_has_system(current, SYSTEM__SYSLOG_READ);
2048 break;
2049 case SYSLOG_ACTION_CONSOLE_OFF: /* Disable logging to console */
2050 case SYSLOG_ACTION_CONSOLE_ON: /* Enable logging to console */
2051 /* Set level of messages printed to console */
2052 case SYSLOG_ACTION_CONSOLE_LEVEL:
2053 rc = task_has_system(current, SYSTEM__SYSLOG_CONSOLE);
2054 break;
2055 case SYSLOG_ACTION_CLOSE: /* Close log */
2056 case SYSLOG_ACTION_OPEN: /* Open log */
2057 case SYSLOG_ACTION_READ: /* Read from log */
2058 case SYSLOG_ACTION_READ_CLEAR: /* Read/clear last kernel messages */
2059 case SYSLOG_ACTION_CLEAR: /* Clear ring buffer */
2060 default:
2061 rc = task_has_system(current, SYSTEM__SYSLOG_MOD);
2062 break;
2063 }
2064 return rc;
2065}
2066
2067/*
2068 * Check that a process has enough memory to allocate a new virtual
2069 * mapping. 0 means there is enough memory for the allocation to
2070 * succeed and -ENOMEM implies there is not.
2071 *
2072 * Do not audit the selinux permission check, as this is applied to all
2073 * processes that allocate mappings.
2074 */
2075static int selinux_vm_enough_memory(struct mm_struct *mm, long pages)
2076{
2077 int rc, cap_sys_admin = 0;
2078
2079 rc = selinux_capable(current_cred(), &init_user_ns, CAP_SYS_ADMIN,
2080 SECURITY_CAP_NOAUDIT);
2081 if (rc == 0)
2082 cap_sys_admin = 1;
2083
2084 return __vm_enough_memory(mm, pages, cap_sys_admin);
2085}
2086
2087/* binprm security operations */
2088
2089static int selinux_bprm_set_creds(struct linux_binprm *bprm)
2090{
2091 const struct task_security_struct *old_tsec;
2092 struct task_security_struct *new_tsec;
2093 struct inode_security_struct *isec;
2094 struct common_audit_data ad;
2095 struct inode *inode = file_inode(bprm->file);
2096 int rc;
2097
2098 rc = cap_bprm_set_creds(bprm);
2099 if (rc)
2100 return rc;
2101
2102 /* SELinux context only depends on initial program or script and not
2103 * the script interpreter */
2104 if (bprm->cred_prepared)
2105 return 0;
2106
2107 old_tsec = current_security();
2108 new_tsec = bprm->cred->security;
2109 isec = inode->i_security;
2110
2111 /* Default to the current task SID. */
2112 new_tsec->sid = old_tsec->sid;
2113 new_tsec->osid = old_tsec->sid;
2114
2115 /* Reset fs, key, and sock SIDs on execve. */
2116 new_tsec->create_sid = 0;
2117 new_tsec->keycreate_sid = 0;
2118 new_tsec->sockcreate_sid = 0;
2119
2120 if (old_tsec->exec_sid) {
2121 new_tsec->sid = old_tsec->exec_sid;
2122 /* Reset exec SID on execve. */
2123 new_tsec->exec_sid = 0;
2124
2125 /*
2126 * Minimize confusion: if no_new_privs and a transition is
2127 * explicitly requested, then fail the exec.
2128 */
2129 if (bprm->unsafe & LSM_UNSAFE_NO_NEW_PRIVS)
2130 return -EPERM;
2131 } else {
2132 /* Check for a default transition on this program. */
2133 rc = security_transition_sid(old_tsec->sid, isec->sid,
2134 SECCLASS_PROCESS, NULL,
2135 &new_tsec->sid);
2136 if (rc)
2137 return rc;
2138 }
2139
2140 ad.type = LSM_AUDIT_DATA_PATH;
2141 ad.u.path = bprm->file->f_path;
2142
2143 if ((bprm->file->f_path.mnt->mnt_flags & MNT_NOSUID) ||
2144 (bprm->unsafe & LSM_UNSAFE_NO_NEW_PRIVS))
2145 new_tsec->sid = old_tsec->sid;
2146
2147 if (new_tsec->sid == old_tsec->sid) {
2148 rc = avc_has_perm(old_tsec->sid, isec->sid,
2149 SECCLASS_FILE, FILE__EXECUTE_NO_TRANS, &ad);
2150 if (rc)
2151 return rc;
2152 } else {
2153 /* Check permissions for the transition. */
2154 rc = avc_has_perm(old_tsec->sid, new_tsec->sid,
2155 SECCLASS_PROCESS, PROCESS__TRANSITION, &ad);
2156 if (rc)
2157 return rc;
2158
2159 rc = avc_has_perm(new_tsec->sid, isec->sid,
2160 SECCLASS_FILE, FILE__ENTRYPOINT, &ad);
2161 if (rc)
2162 return rc;
2163
2164 /* Check for shared state */
2165 if (bprm->unsafe & LSM_UNSAFE_SHARE) {
2166 rc = avc_has_perm(old_tsec->sid, new_tsec->sid,
2167 SECCLASS_PROCESS, PROCESS__SHARE,
2168 NULL);
2169 if (rc)
2170 return -EPERM;
2171 }
2172
2173 /* Make sure that anyone attempting to ptrace over a task that
2174 * changes its SID has the appropriate permit */
2175 if (bprm->unsafe &
2176 (LSM_UNSAFE_PTRACE | LSM_UNSAFE_PTRACE_CAP)) {
2177 struct task_struct *tracer;
2178 struct task_security_struct *sec;
2179 u32 ptsid = 0;
2180
2181 rcu_read_lock();
2182 tracer = ptrace_parent(current);
2183 if (likely(tracer != NULL)) {
2184 sec = __task_cred(tracer)->security;
2185 ptsid = sec->sid;
2186 }
2187 rcu_read_unlock();
2188
2189 if (ptsid != 0) {
2190 rc = avc_has_perm(ptsid, new_tsec->sid,
2191 SECCLASS_PROCESS,
2192 PROCESS__PTRACE, NULL);
2193 if (rc)
2194 return -EPERM;
2195 }
2196 }
2197
2198 /* Clear any possibly unsafe personality bits on exec: */
2199 bprm->per_clear |= PER_CLEAR_ON_SETID;
2200 }
2201
2202 return 0;
2203}
2204
2205static int selinux_bprm_secureexec(struct linux_binprm *bprm)
2206{
2207 const struct task_security_struct *tsec = current_security();
2208 u32 sid, osid;
2209 int atsecure = 0;
2210
2211 sid = tsec->sid;
2212 osid = tsec->osid;
2213
2214 if (osid != sid) {
2215 /* Enable secure mode for SIDs transitions unless
2216 the noatsecure permission is granted between
2217 the two SIDs, i.e. ahp returns 0. */
2218 atsecure = avc_has_perm(osid, sid,
2219 SECCLASS_PROCESS,
2220 PROCESS__NOATSECURE, NULL);
2221 }
2222
2223 return (atsecure || cap_bprm_secureexec(bprm));
2224}
2225
2226static int match_file(const void *p, struct file *file, unsigned fd)
2227{
2228 return file_has_perm(p, file, file_to_av(file)) ? fd + 1 : 0;
2229}
2230
2231/* Derived from fs/exec.c:flush_old_files. */
2232static inline void flush_unauthorized_files(const struct cred *cred,
2233 struct files_struct *files)
2234{
2235 struct file *file, *devnull = NULL;
2236 struct tty_struct *tty;
2237 int drop_tty = 0;
2238 unsigned n;
2239
2240 tty = get_current_tty();
2241 if (tty) {
2242 spin_lock(&tty_files_lock);
2243 if (!list_empty(&tty->tty_files)) {
2244 struct tty_file_private *file_priv;
2245
2246 /* Revalidate access to controlling tty.
2247 Use file_path_has_perm on the tty path directly
2248 rather than using file_has_perm, as this particular
2249 open file may belong to another process and we are
2250 only interested in the inode-based check here. */
2251 file_priv = list_first_entry(&tty->tty_files,
2252 struct tty_file_private, list);
2253 file = file_priv->file;
2254 if (file_path_has_perm(cred, file, FILE__READ | FILE__WRITE))
2255 drop_tty = 1;
2256 }
2257 spin_unlock(&tty_files_lock);
2258 tty_kref_put(tty);
2259 }
2260 /* Reset controlling tty. */
2261 if (drop_tty)
2262 no_tty();
2263
2264 /* Revalidate access to inherited open files. */
2265 n = iterate_fd(files, 0, match_file, cred);
2266 if (!n) /* none found? */
2267 return;
2268
2269 devnull = dentry_open(&selinux_null, O_RDWR, cred);
2270 if (IS_ERR(devnull))
2271 devnull = NULL;
2272 /* replace all the matching ones with this */
2273 do {
2274 replace_fd(n - 1, devnull, 0);
2275 } while ((n = iterate_fd(files, n, match_file, cred)) != 0);
2276 if (devnull)
2277 fput(devnull);
2278}
2279
2280/*
2281 * Prepare a process for imminent new credential changes due to exec
2282 */
2283static void selinux_bprm_committing_creds(struct linux_binprm *bprm)
2284{
2285 struct task_security_struct *new_tsec;
2286 struct rlimit *rlim, *initrlim;
2287 int rc, i;
2288
2289 new_tsec = bprm->cred->security;
2290 if (new_tsec->sid == new_tsec->osid)
2291 return;
2292
2293 /* Close files for which the new task SID is not authorized. */
2294 flush_unauthorized_files(bprm->cred, current->files);
2295
2296 /* Always clear parent death signal on SID transitions. */
2297 current->pdeath_signal = 0;
2298
2299 /* Check whether the new SID can inherit resource limits from the old
2300 * SID. If not, reset all soft limits to the lower of the current
2301 * task's hard limit and the init task's soft limit.
2302 *
2303 * Note that the setting of hard limits (even to lower them) can be
2304 * controlled by the setrlimit check. The inclusion of the init task's
2305 * soft limit into the computation is to avoid resetting soft limits
2306 * higher than the default soft limit for cases where the default is
2307 * lower than the hard limit, e.g. RLIMIT_CORE or RLIMIT_STACK.
2308 */
2309 rc = avc_has_perm(new_tsec->osid, new_tsec->sid, SECCLASS_PROCESS,
2310 PROCESS__RLIMITINH, NULL);
2311 if (rc) {
2312 /* protect against do_prlimit() */
2313 task_lock(current);
2314 for (i = 0; i < RLIM_NLIMITS; i++) {
2315 rlim = current->signal->rlim + i;
2316 initrlim = init_task.signal->rlim + i;
2317 rlim->rlim_cur = min(rlim->rlim_max, initrlim->rlim_cur);
2318 }
2319 task_unlock(current);
2320 update_rlimit_cpu(current, rlimit(RLIMIT_CPU));
2321 }
2322}
2323
2324/*
2325 * Clean up the process immediately after the installation of new credentials
2326 * due to exec
2327 */
2328static void selinux_bprm_committed_creds(struct linux_binprm *bprm)
2329{
2330 const struct task_security_struct *tsec = current_security();
2331 struct itimerval itimer;
2332 u32 osid, sid;
2333 int rc, i;
2334
2335 osid = tsec->osid;
2336 sid = tsec->sid;
2337
2338 if (sid == osid)
2339 return;
2340
2341 /* Check whether the new SID can inherit signal state from the old SID.
2342 * If not, clear itimers to avoid subsequent signal generation and
2343 * flush and unblock signals.
2344 *
2345 * This must occur _after_ the task SID has been updated so that any
2346 * kill done after the flush will be checked against the new SID.
2347 */
2348 rc = avc_has_perm(osid, sid, SECCLASS_PROCESS, PROCESS__SIGINH, NULL);
2349 if (rc) {
2350 memset(&itimer, 0, sizeof itimer);
2351 for (i = 0; i < 3; i++)
2352 do_setitimer(i, &itimer, NULL);
2353 spin_lock_irq(¤t->sighand->siglock);
2354 if (!(current->signal->flags & SIGNAL_GROUP_EXIT)) {
2355 __flush_signals(current);
2356 flush_signal_handlers(current, 1);
2357 sigemptyset(¤t->blocked);
2358 }
2359 spin_unlock_irq(¤t->sighand->siglock);
2360 }
2361
2362 /* Wake up the parent if it is waiting so that it can recheck
2363 * wait permission to the new task SID. */
2364 read_lock(&tasklist_lock);
2365 __wake_up_parent(current, current->real_parent);
2366 read_unlock(&tasklist_lock);
2367}
2368
2369/* superblock security operations */
2370
2371static int selinux_sb_alloc_security(struct super_block *sb)
2372{
2373 return superblock_alloc_security(sb);
2374}
2375
2376static void selinux_sb_free_security(struct super_block *sb)
2377{
2378 superblock_free_security(sb);
2379}
2380
2381static inline int match_prefix(char *prefix, int plen, char *option, int olen)
2382{
2383 if (plen > olen)
2384 return 0;
2385
2386 return !memcmp(prefix, option, plen);
2387}
2388
2389static inline int selinux_option(char *option, int len)
2390{
2391 return (match_prefix(CONTEXT_STR, sizeof(CONTEXT_STR)-1, option, len) ||
2392 match_prefix(FSCONTEXT_STR, sizeof(FSCONTEXT_STR)-1, option, len) ||
2393 match_prefix(DEFCONTEXT_STR, sizeof(DEFCONTEXT_STR)-1, option, len) ||
2394 match_prefix(ROOTCONTEXT_STR, sizeof(ROOTCONTEXT_STR)-1, option, len) ||
2395 match_prefix(LABELSUPP_STR, sizeof(LABELSUPP_STR)-1, option, len));
2396}
2397
2398static inline void take_option(char **to, char *from, int *first, int len)
2399{
2400 if (!*first) {
2401 **to = ',';
2402 *to += 1;
2403 } else
2404 *first = 0;
2405 memcpy(*to, from, len);
2406 *to += len;
2407}
2408
2409static inline void take_selinux_option(char **to, char *from, int *first,
2410 int len)
2411{
2412 int current_size = 0;
2413
2414 if (!*first) {
2415 **to = '|';
2416 *to += 1;
2417 } else
2418 *first = 0;
2419
2420 while (current_size < len) {
2421 if (*from != '"') {
2422 **to = *from;
2423 *to += 1;
2424 }
2425 from += 1;
2426 current_size += 1;
2427 }
2428}
2429
2430static int selinux_sb_copy_data(char *orig, char *copy)
2431{
2432 int fnosec, fsec, rc = 0;
2433 char *in_save, *in_curr, *in_end;
2434 char *sec_curr, *nosec_save, *nosec;
2435 int open_quote = 0;
2436
2437 in_curr = orig;
2438 sec_curr = copy;
2439
2440 nosec = (char *)get_zeroed_page(GFP_KERNEL);
2441 if (!nosec) {
2442 rc = -ENOMEM;
2443 goto out;
2444 }
2445
2446 nosec_save = nosec;
2447 fnosec = fsec = 1;
2448 in_save = in_end = orig;
2449
2450 do {
2451 if (*in_end == '"')
2452 open_quote = !open_quote;
2453 if ((*in_end == ',' && open_quote == 0) ||
2454 *in_end == '\0') {
2455 int len = in_end - in_curr;
2456
2457 if (selinux_option(in_curr, len))
2458 take_selinux_option(&sec_curr, in_curr, &fsec, len);
2459 else
2460 take_option(&nosec, in_curr, &fnosec, len);
2461
2462 in_curr = in_end + 1;
2463 }
2464 } while (*in_end++);
2465
2466 strcpy(in_save, nosec_save);
2467 free_page((unsigned long)nosec_save);
2468out:
2469 return rc;
2470}
2471
2472static int selinux_sb_remount(struct super_block *sb, void *data)
2473{
2474 int rc, i, *flags;
2475 struct security_mnt_opts opts;
2476 char *secdata, **mount_options;
2477 struct superblock_security_struct *sbsec = sb->s_security;
2478
2479 if (!(sbsec->flags & SE_SBINITIALIZED))
2480 return 0;
2481
2482 if (!data)
2483 return 0;
2484
2485 if (sb->s_type->fs_flags & FS_BINARY_MOUNTDATA)
2486 return 0;
2487
2488 security_init_mnt_opts(&opts);
2489 secdata = alloc_secdata();
2490 if (!secdata)
2491 return -ENOMEM;
2492 rc = selinux_sb_copy_data(data, secdata);
2493 if (rc)
2494 goto out_free_secdata;
2495
2496 rc = selinux_parse_opts_str(secdata, &opts);
2497 if (rc)
2498 goto out_free_secdata;
2499
2500 mount_options = opts.mnt_opts;
2501 flags = opts.mnt_opts_flags;
2502
2503 for (i = 0; i < opts.num_mnt_opts; i++) {
2504 u32 sid;
2505 size_t len;
2506
2507 if (flags[i] == SBLABEL_MNT)
2508 continue;
2509 len = strlen(mount_options[i]);
2510 rc = security_context_to_sid(mount_options[i], len, &sid,
2511 GFP_KERNEL);
2512 if (rc) {
2513 printk(KERN_WARNING "SELinux: security_context_to_sid"
2514 "(%s) failed for (dev %s, type %s) errno=%d\n",
2515 mount_options[i], sb->s_id, sb->s_type->name, rc);
2516 goto out_free_opts;
2517 }
2518 rc = -EINVAL;
2519 switch (flags[i]) {
2520 case FSCONTEXT_MNT:
2521 if (bad_option(sbsec, FSCONTEXT_MNT, sbsec->sid, sid))
2522 goto out_bad_option;
2523 break;
2524 case CONTEXT_MNT:
2525 if (bad_option(sbsec, CONTEXT_MNT, sbsec->mntpoint_sid, sid))
2526 goto out_bad_option;
2527 break;
2528 case ROOTCONTEXT_MNT: {
2529 struct inode_security_struct *root_isec;
2530 root_isec = sb->s_root->d_inode->i_security;
2531
2532 if (bad_option(sbsec, ROOTCONTEXT_MNT, root_isec->sid, sid))
2533 goto out_bad_option;
2534 break;
2535 }
2536 case DEFCONTEXT_MNT:
2537 if (bad_option(sbsec, DEFCONTEXT_MNT, sbsec->def_sid, sid))
2538 goto out_bad_option;
2539 break;
2540 default:
2541 goto out_free_opts;
2542 }
2543 }
2544
2545 rc = 0;
2546out_free_opts:
2547 security_free_mnt_opts(&opts);
2548out_free_secdata:
2549 free_secdata(secdata);
2550 return rc;
2551out_bad_option:
2552 printk(KERN_WARNING "SELinux: unable to change security options "
2553 "during remount (dev %s, type=%s)\n", sb->s_id,
2554 sb->s_type->name);
2555 goto out_free_opts;
2556}
2557
2558static int selinux_sb_kern_mount(struct super_block *sb, int flags, void *data)
2559{
2560 const struct cred *cred = current_cred();
2561 struct common_audit_data ad;
2562 int rc;
2563
2564 rc = superblock_doinit(sb, data);
2565 if (rc)
2566 return rc;
2567
2568 /* Allow all mounts performed by the kernel */
2569 if (flags & MS_KERNMOUNT)
2570 return 0;
2571
2572 ad.type = LSM_AUDIT_DATA_DENTRY;
2573 ad.u.dentry = sb->s_root;
2574 return superblock_has_perm(cred, sb, FILESYSTEM__MOUNT, &ad);
2575}
2576
2577static int selinux_sb_statfs(struct dentry *dentry)
2578{
2579 const struct cred *cred = current_cred();
2580 struct common_audit_data ad;
2581
2582 ad.type = LSM_AUDIT_DATA_DENTRY;
2583 ad.u.dentry = dentry->d_sb->s_root;
2584 return superblock_has_perm(cred, dentry->d_sb, FILESYSTEM__GETATTR, &ad);
2585}
2586
2587static int selinux_mount(const char *dev_name,
2588 struct path *path,
2589 const char *type,
2590 unsigned long flags,
2591 void *data)
2592{
2593 const struct cred *cred = current_cred();
2594
2595 if (flags & MS_REMOUNT)
2596 return superblock_has_perm(cred, path->dentry->d_sb,
2597 FILESYSTEM__REMOUNT, NULL);
2598 else
2599 return path_has_perm(cred, path, FILE__MOUNTON);
2600}
2601
2602static int selinux_umount(struct vfsmount *mnt, int flags)
2603{
2604 const struct cred *cred = current_cred();
2605
2606 return superblock_has_perm(cred, mnt->mnt_sb,
2607 FILESYSTEM__UNMOUNT, NULL);
2608}
2609
2610/* inode security operations */
2611
2612static int selinux_inode_alloc_security(struct inode *inode)
2613{
2614 return inode_alloc_security(inode);
2615}
2616
2617static void selinux_inode_free_security(struct inode *inode)
2618{
2619 inode_free_security(inode);
2620}
2621
2622static int selinux_dentry_init_security(struct dentry *dentry, int mode,
2623 struct qstr *name, void **ctx,
2624 u32 *ctxlen)
2625{
2626 const struct cred *cred = current_cred();
2627 struct task_security_struct *tsec;
2628 struct inode_security_struct *dsec;
2629 struct superblock_security_struct *sbsec;
2630 struct inode *dir = dentry->d_parent->d_inode;
2631 u32 newsid;
2632 int rc;
2633
2634 tsec = cred->security;
2635 dsec = dir->i_security;
2636 sbsec = dir->i_sb->s_security;
2637
2638 if (tsec->create_sid && sbsec->behavior != SECURITY_FS_USE_MNTPOINT) {
2639 newsid = tsec->create_sid;
2640 } else {
2641 rc = security_transition_sid(tsec->sid, dsec->sid,
2642 inode_mode_to_security_class(mode),
2643 name,
2644 &newsid);
2645 if (rc) {
2646 printk(KERN_WARNING
2647 "%s: security_transition_sid failed, rc=%d\n",
2648 __func__, -rc);
2649 return rc;
2650 }
2651 }
2652
2653 return security_sid_to_context(newsid, (char **)ctx, ctxlen);
2654}
2655
2656static int selinux_inode_init_security(struct inode *inode, struct inode *dir,
2657 const struct qstr *qstr,
2658 const char **name,
2659 void **value, size_t *len)
2660{
2661 const struct task_security_struct *tsec = current_security();
2662 struct inode_security_struct *dsec;
2663 struct superblock_security_struct *sbsec;
2664 u32 sid, newsid, clen;
2665 int rc;
2666 char *context;
2667
2668 dsec = dir->i_security;
2669 sbsec = dir->i_sb->s_security;
2670
2671 sid = tsec->sid;
2672 newsid = tsec->create_sid;
2673
2674 if ((sbsec->flags & SE_SBINITIALIZED) &&
2675 (sbsec->behavior == SECURITY_FS_USE_MNTPOINT))
2676 newsid = sbsec->mntpoint_sid;
2677 else if (!newsid || !(sbsec->flags & SBLABEL_MNT)) {
2678 rc = security_transition_sid(sid, dsec->sid,
2679 inode_mode_to_security_class(inode->i_mode),
2680 qstr, &newsid);
2681 if (rc) {
2682 printk(KERN_WARNING "%s: "
2683 "security_transition_sid failed, rc=%d (dev=%s "
2684 "ino=%ld)\n",
2685 __func__,
2686 -rc, inode->i_sb->s_id, inode->i_ino);
2687 return rc;
2688 }
2689 }
2690
2691 /* Possibly defer initialization to selinux_complete_init. */
2692 if (sbsec->flags & SE_SBINITIALIZED) {
2693 struct inode_security_struct *isec = inode->i_security;
2694 isec->sclass = inode_mode_to_security_class(inode->i_mode);
2695 isec->sid = newsid;
2696 isec->initialized = 1;
2697 }
2698
2699 if (!ss_initialized || !(sbsec->flags & SBLABEL_MNT))
2700 return -EOPNOTSUPP;
2701
2702 if (name)
2703 *name = XATTR_SELINUX_SUFFIX;
2704
2705 if (value && len) {
2706 rc = security_sid_to_context_force(newsid, &context, &clen);
2707 if (rc)
2708 return rc;
2709 *value = context;
2710 *len = clen;
2711 }
2712
2713 return 0;
2714}
2715
2716static int selinux_inode_create(struct inode *dir, struct dentry *dentry, umode_t mode)
2717{
2718 return may_create(dir, dentry, SECCLASS_FILE);
2719}
2720
2721static int selinux_inode_link(struct dentry *old_dentry, struct inode *dir, struct dentry *new_dentry)
2722{
2723 return may_link(dir, old_dentry, MAY_LINK);
2724}
2725
2726static int selinux_inode_unlink(struct inode *dir, struct dentry *dentry)
2727{
2728 return may_link(dir, dentry, MAY_UNLINK);
2729}
2730
2731static int selinux_inode_symlink(struct inode *dir, struct dentry *dentry, const char *name)
2732{
2733 return may_create(dir, dentry, SECCLASS_LNK_FILE);
2734}
2735
2736static int selinux_inode_mkdir(struct inode *dir, struct dentry *dentry, umode_t mask)
2737{
2738 return may_create(dir, dentry, SECCLASS_DIR);
2739}
2740
2741static int selinux_inode_rmdir(struct inode *dir, struct dentry *dentry)
2742{
2743 return may_link(dir, dentry, MAY_RMDIR);
2744}
2745
2746static int selinux_inode_mknod(struct inode *dir, struct dentry *dentry, umode_t mode, dev_t dev)
2747{
2748 return may_create(dir, dentry, inode_mode_to_security_class(mode));
2749}
2750
2751static int selinux_inode_rename(struct inode *old_inode, struct dentry *old_dentry,
2752 struct inode *new_inode, struct dentry *new_dentry)
2753{
2754 return may_rename(old_inode, old_dentry, new_inode, new_dentry);
2755}
2756
2757static int selinux_inode_readlink(struct dentry *dentry)
2758{
2759 const struct cred *cred = current_cred();
2760
2761 return dentry_has_perm(cred, dentry, FILE__READ);
2762}
2763
2764static int selinux_inode_follow_link(struct dentry *dentry, struct nameidata *nameidata)
2765{
2766 const struct cred *cred = current_cred();
2767
2768 return dentry_has_perm(cred, dentry, FILE__READ);
2769}
2770
2771static noinline int audit_inode_permission(struct inode *inode,
2772 u32 perms, u32 audited, u32 denied,
2773 unsigned flags)
2774{
2775 struct common_audit_data ad;
2776 struct inode_security_struct *isec = inode->i_security;
2777 int rc;
2778
2779 ad.type = LSM_AUDIT_DATA_INODE;
2780 ad.u.inode = inode;
2781
2782 rc = slow_avc_audit(current_sid(), isec->sid, isec->sclass, perms,
2783 audited, denied, &ad, flags);
2784 if (rc)
2785 return rc;
2786 return 0;
2787}
2788
2789static int selinux_inode_permission(struct inode *inode, int mask)
2790{
2791 const struct cred *cred = current_cred();
2792 u32 perms;
2793 bool from_access;
2794 unsigned flags = mask & MAY_NOT_BLOCK;
2795 struct inode_security_struct *isec;
2796 u32 sid;
2797 struct av_decision avd;
2798 int rc, rc2;
2799 u32 audited, denied;
2800
2801 from_access = mask & MAY_ACCESS;
2802 mask &= (MAY_READ|MAY_WRITE|MAY_EXEC|MAY_APPEND);
2803
2804 /* No permission to check. Existence test. */
2805 if (!mask)
2806 return 0;
2807
2808 validate_creds(cred);
2809
2810 if (unlikely(IS_PRIVATE(inode)))
2811 return 0;
2812
2813 perms = file_mask_to_av(inode->i_mode, mask);
2814
2815 sid = cred_sid(cred);
2816 isec = inode->i_security;
2817
2818 rc = avc_has_perm_noaudit(sid, isec->sid, isec->sclass, perms, 0, &avd);
2819 audited = avc_audit_required(perms, &avd, rc,
2820 from_access ? FILE__AUDIT_ACCESS : 0,
2821 &denied);
2822 if (likely(!audited))
2823 return rc;
2824
2825 rc2 = audit_inode_permission(inode, perms, audited, denied, flags);
2826 if (rc2)
2827 return rc2;
2828 return rc;
2829}
2830
2831static int selinux_inode_setattr(struct dentry *dentry, struct iattr *iattr)
2832{
2833 const struct cred *cred = current_cred();
2834 unsigned int ia_valid = iattr->ia_valid;
2835 __u32 av = FILE__WRITE;
2836
2837 /* ATTR_FORCE is just used for ATTR_KILL_S[UG]ID. */
2838 if (ia_valid & ATTR_FORCE) {
2839 ia_valid &= ~(ATTR_KILL_SUID | ATTR_KILL_SGID | ATTR_MODE |
2840 ATTR_FORCE);
2841 if (!ia_valid)
2842 return 0;
2843 }
2844
2845 if (ia_valid & (ATTR_MODE | ATTR_UID | ATTR_GID |
2846 ATTR_ATIME_SET | ATTR_MTIME_SET | ATTR_TIMES_SET))
2847 return dentry_has_perm(cred, dentry, FILE__SETATTR);
2848
2849 if (selinux_policycap_openperm && (ia_valid & ATTR_SIZE))
2850 av |= FILE__OPEN;
2851
2852 return dentry_has_perm(cred, dentry, av);
2853}
2854
2855static int selinux_inode_getattr(struct vfsmount *mnt, struct dentry *dentry)
2856{
2857 const struct cred *cred = current_cred();
2858 struct path path;
2859
2860 path.dentry = dentry;
2861 path.mnt = mnt;
2862
2863 return path_has_perm(cred, &path, FILE__GETATTR);
2864}
2865
2866static int selinux_inode_setotherxattr(struct dentry *dentry, const char *name)
2867{
2868 const struct cred *cred = current_cred();
2869
2870 if (!strncmp(name, XATTR_SECURITY_PREFIX,
2871 sizeof XATTR_SECURITY_PREFIX - 1)) {
2872 if (!strcmp(name, XATTR_NAME_CAPS)) {
2873 if (!capable(CAP_SETFCAP))
2874 return -EPERM;
2875 } else if (!capable(CAP_SYS_ADMIN)) {
2876 /* A different attribute in the security namespace.
2877 Restrict to administrator. */
2878 return -EPERM;
2879 }
2880 }
2881
2882 /* Not an attribute we recognize, so just check the
2883 ordinary setattr permission. */
2884 return dentry_has_perm(cred, dentry, FILE__SETATTR);
2885}
2886
2887static int selinux_inode_setxattr(struct dentry *dentry, const char *name,
2888 const void *value, size_t size, int flags)
2889{
2890 struct inode *inode = dentry->d_inode;
2891 struct inode_security_struct *isec = inode->i_security;
2892 struct superblock_security_struct *sbsec;
2893 struct common_audit_data ad;
2894 u32 newsid, sid = current_sid();
2895 int rc = 0;
2896
2897 if (strcmp(name, XATTR_NAME_SELINUX))
2898 return selinux_inode_setotherxattr(dentry, name);
2899
2900 sbsec = inode->i_sb->s_security;
2901 if (!(sbsec->flags & SBLABEL_MNT))
2902 return -EOPNOTSUPP;
2903
2904 if (!inode_owner_or_capable(inode))
2905 return -EPERM;
2906
2907 ad.type = LSM_AUDIT_DATA_DENTRY;
2908 ad.u.dentry = dentry;
2909
2910 rc = avc_has_perm(sid, isec->sid, isec->sclass,
2911 FILE__RELABELFROM, &ad);
2912 if (rc)
2913 return rc;
2914
2915 rc = security_context_to_sid(value, size, &newsid, GFP_KERNEL);
2916 if (rc == -EINVAL) {
2917 if (!capable(CAP_MAC_ADMIN)) {
2918 struct audit_buffer *ab;
2919 size_t audit_size;
2920 const char *str;
2921
2922 /* We strip a nul only if it is at the end, otherwise the
2923 * context contains a nul and we should audit that */
2924 if (value) {
2925 str = value;
2926 if (str[size - 1] == '\0')
2927 audit_size = size - 1;
2928 else
2929 audit_size = size;
2930 } else {
2931 str = "";
2932 audit_size = 0;
2933 }
2934 ab = audit_log_start(current->audit_context, GFP_ATOMIC, AUDIT_SELINUX_ERR);
2935 audit_log_format(ab, "op=setxattr invalid_context=");
2936 audit_log_n_untrustedstring(ab, value, audit_size);
2937 audit_log_end(ab);
2938
2939 return rc;
2940 }
2941 rc = security_context_to_sid_force(value, size, &newsid);
2942 }
2943 if (rc)
2944 return rc;
2945
2946 rc = avc_has_perm(sid, newsid, isec->sclass,
2947 FILE__RELABELTO, &ad);
2948 if (rc)
2949 return rc;
2950
2951 rc = security_validate_transition(isec->sid, newsid, sid,
2952 isec->sclass);
2953 if (rc)
2954 return rc;
2955
2956 return avc_has_perm(newsid,
2957 sbsec->sid,
2958 SECCLASS_FILESYSTEM,
2959 FILESYSTEM__ASSOCIATE,
2960 &ad);
2961}
2962
2963static void selinux_inode_post_setxattr(struct dentry *dentry, const char *name,
2964 const void *value, size_t size,
2965 int flags)
2966{
2967 struct inode *inode = dentry->d_inode;
2968 struct inode_security_struct *isec = inode->i_security;
2969 u32 newsid;
2970 int rc;
2971
2972 if (strcmp(name, XATTR_NAME_SELINUX)) {
2973 /* Not an attribute we recognize, so nothing to do. */
2974 return;
2975 }
2976
2977 rc = security_context_to_sid_force(value, size, &newsid);
2978 if (rc) {
2979 printk(KERN_ERR "SELinux: unable to map context to SID"
2980 "for (%s, %lu), rc=%d\n",
2981 inode->i_sb->s_id, inode->i_ino, -rc);
2982 return;
2983 }
2984
2985 isec->sclass = inode_mode_to_security_class(inode->i_mode);
2986 isec->sid = newsid;
2987 isec->initialized = 1;
2988
2989 return;
2990}
2991
2992static int selinux_inode_getxattr(struct dentry *dentry, const char *name)
2993{
2994 const struct cred *cred = current_cred();
2995
2996 return dentry_has_perm(cred, dentry, FILE__GETATTR);
2997}
2998
2999static int selinux_inode_listxattr(struct dentry *dentry)
3000{
3001 const struct cred *cred = current_cred();
3002
3003 return dentry_has_perm(cred, dentry, FILE__GETATTR);
3004}
3005
3006static int selinux_inode_removexattr(struct dentry *dentry, const char *name)
3007{
3008 if (strcmp(name, XATTR_NAME_SELINUX))
3009 return selinux_inode_setotherxattr(dentry, name);
3010
3011 /* No one is allowed to remove a SELinux security label.
3012 You can change the label, but all data must be labeled. */
3013 return -EACCES;
3014}
3015
3016/*
3017 * Copy the inode security context value to the user.
3018 *
3019 * Permission check is handled by selinux_inode_getxattr hook.
3020 */
3021static int selinux_inode_getsecurity(const struct inode *inode, const char *name, void **buffer, bool alloc)
3022{
3023 u32 size;
3024 int error;
3025 char *context = NULL;
3026 struct inode_security_struct *isec = inode->i_security;
3027
3028 if (strcmp(name, XATTR_SELINUX_SUFFIX))
3029 return -EOPNOTSUPP;
3030
3031 /*
3032 * If the caller has CAP_MAC_ADMIN, then get the raw context
3033 * value even if it is not defined by current policy; otherwise,
3034 * use the in-core value under current policy.
3035 * Use the non-auditing forms of the permission checks since
3036 * getxattr may be called by unprivileged processes commonly
3037 * and lack of permission just means that we fall back to the
3038 * in-core context value, not a denial.
3039 */
3040 error = selinux_capable(current_cred(), &init_user_ns, CAP_MAC_ADMIN,
3041 SECURITY_CAP_NOAUDIT);
3042 if (!error)
3043 error = security_sid_to_context_force(isec->sid, &context,
3044 &size);
3045 else
3046 error = security_sid_to_context(isec->sid, &context, &size);
3047 if (error)
3048 return error;
3049 error = size;
3050 if (alloc) {
3051 *buffer = context;
3052 goto out_nofree;
3053 }
3054 kfree(context);
3055out_nofree:
3056 return error;
3057}
3058
3059static int selinux_inode_setsecurity(struct inode *inode, const char *name,
3060 const void *value, size_t size, int flags)
3061{
3062 struct inode_security_struct *isec = inode->i_security;
3063 u32 newsid;
3064 int rc;
3065
3066 if (strcmp(name, XATTR_SELINUX_SUFFIX))
3067 return -EOPNOTSUPP;
3068
3069 if (!value || !size)
3070 return -EACCES;
3071
3072 rc = security_context_to_sid((void *)value, size, &newsid, GFP_KERNEL);
3073 if (rc)
3074 return rc;
3075
3076 isec->sclass = inode_mode_to_security_class(inode->i_mode);
3077 isec->sid = newsid;
3078 isec->initialized = 1;
3079 return 0;
3080}
3081
3082static int selinux_inode_listsecurity(struct inode *inode, char *buffer, size_t buffer_size)
3083{
3084 const int len = sizeof(XATTR_NAME_SELINUX);
3085 if (buffer && len <= buffer_size)
3086 memcpy(buffer, XATTR_NAME_SELINUX, len);
3087 return len;
3088}
3089
3090static void selinux_inode_getsecid(const struct inode *inode, u32 *secid)
3091{
3092 struct inode_security_struct *isec = inode->i_security;
3093 *secid = isec->sid;
3094}
3095
3096/* file security operations */
3097
3098static int selinux_revalidate_file_permission(struct file *file, int mask)
3099{
3100 const struct cred *cred = current_cred();
3101 struct inode *inode = file_inode(file);
3102
3103 /* file_mask_to_av won't add FILE__WRITE if MAY_APPEND is set */
3104 if ((file->f_flags & O_APPEND) && (mask & MAY_WRITE))
3105 mask |= MAY_APPEND;
3106
3107 return file_has_perm(cred, file,
3108 file_mask_to_av(inode->i_mode, mask));
3109}
3110
3111static int selinux_file_permission(struct file *file, int mask)
3112{
3113 struct inode *inode = file_inode(file);
3114 struct file_security_struct *fsec = file->f_security;
3115 struct inode_security_struct *isec = inode->i_security;
3116 u32 sid = current_sid();
3117
3118 if (!mask)
3119 /* No permission to check. Existence test. */
3120 return 0;
3121
3122 if (sid == fsec->sid && fsec->isid == isec->sid &&
3123 fsec->pseqno == avc_policy_seqno())
3124 /* No change since file_open check. */
3125 return 0;
3126
3127 return selinux_revalidate_file_permission(file, mask);
3128}
3129
3130static int selinux_file_alloc_security(struct file *file)
3131{
3132 return file_alloc_security(file);
3133}
3134
3135static void selinux_file_free_security(struct file *file)
3136{
3137 file_free_security(file);
3138}
3139
3140static int selinux_file_ioctl(struct file *file, unsigned int cmd,
3141 unsigned long arg)
3142{
3143 const struct cred *cred = current_cred();
3144 int error = 0;
3145
3146 switch (cmd) {
3147 case FIONREAD:
3148 /* fall through */
3149 case FIBMAP:
3150 /* fall through */
3151 case FIGETBSZ:
3152 /* fall through */
3153 case FS_IOC_GETFLAGS:
3154 /* fall through */
3155 case FS_IOC_GETVERSION:
3156 error = file_has_perm(cred, file, FILE__GETATTR);
3157 break;
3158
3159 case FS_IOC_SETFLAGS:
3160 /* fall through */
3161 case FS_IOC_SETVERSION:
3162 error = file_has_perm(cred, file, FILE__SETATTR);
3163 break;
3164
3165 /* sys_ioctl() checks */
3166 case FIONBIO:
3167 /* fall through */
3168 case FIOASYNC:
3169 error = file_has_perm(cred, file, 0);
3170 break;
3171
3172 case KDSKBENT:
3173 case KDSKBSENT:
3174 error = cred_has_capability(cred, CAP_SYS_TTY_CONFIG,
3175 SECURITY_CAP_AUDIT);
3176 break;
3177
3178 /* default case assumes that the command will go
3179 * to the file's ioctl() function.
3180 */
3181 default:
3182 error = file_has_perm(cred, file, FILE__IOCTL);
3183 }
3184 return error;
3185}
3186
3187static int default_noexec;
3188
3189static int file_map_prot_check(struct file *file, unsigned long prot, int shared)
3190{
3191 const struct cred *cred = current_cred();
3192 int rc = 0;
3193
3194 if (default_noexec &&
3195 (prot & PROT_EXEC) && (!file || (!shared && (prot & PROT_WRITE)))) {
3196 /*
3197 * We are making executable an anonymous mapping or a
3198 * private file mapping that will also be writable.
3199 * This has an additional check.
3200 */
3201 rc = cred_has_perm(cred, cred, PROCESS__EXECMEM);
3202 if (rc)
3203 goto error;
3204 }
3205
3206 if (file) {
3207 /* read access is always possible with a mapping */
3208 u32 av = FILE__READ;
3209
3210 /* write access only matters if the mapping is shared */
3211 if (shared && (prot & PROT_WRITE))
3212 av |= FILE__WRITE;
3213
3214 if (prot & PROT_EXEC)
3215 av |= FILE__EXECUTE;
3216
3217 return file_has_perm(cred, file, av);
3218 }
3219
3220error:
3221 return rc;
3222}
3223
3224static int selinux_mmap_addr(unsigned long addr)
3225{
3226 int rc;
3227
3228 /* do DAC check on address space usage */
3229 rc = cap_mmap_addr(addr);
3230 if (rc)
3231 return rc;
3232
3233 if (addr < CONFIG_LSM_MMAP_MIN_ADDR) {
3234 u32 sid = current_sid();
3235 rc = avc_has_perm(sid, sid, SECCLASS_MEMPROTECT,
3236 MEMPROTECT__MMAP_ZERO, NULL);
3237 }
3238
3239 return rc;
3240}
3241
3242static int selinux_mmap_file(struct file *file, unsigned long reqprot,
3243 unsigned long prot, unsigned long flags)
3244{
3245 if (selinux_checkreqprot)
3246 prot = reqprot;
3247
3248 return file_map_prot_check(file, prot,
3249 (flags & MAP_TYPE) == MAP_SHARED);
3250}
3251
3252static int selinux_file_mprotect(struct vm_area_struct *vma,
3253 unsigned long reqprot,
3254 unsigned long prot)
3255{
3256 const struct cred *cred = current_cred();
3257
3258 if (selinux_checkreqprot)
3259 prot = reqprot;
3260
3261 if (default_noexec &&
3262 (prot & PROT_EXEC) && !(vma->vm_flags & VM_EXEC)) {
3263 int rc = 0;
3264 if (vma->vm_start >= vma->vm_mm->start_brk &&
3265 vma->vm_end <= vma->vm_mm->brk) {
3266 rc = cred_has_perm(cred, cred, PROCESS__EXECHEAP);
3267 } else if (!vma->vm_file &&
3268 vma->vm_start <= vma->vm_mm->start_stack &&
3269 vma->vm_end >= vma->vm_mm->start_stack) {
3270 rc = current_has_perm(current, PROCESS__EXECSTACK);
3271 } else if (vma->vm_file && vma->anon_vma) {
3272 /*
3273 * We are making executable a file mapping that has
3274 * had some COW done. Since pages might have been
3275 * written, check ability to execute the possibly
3276 * modified content. This typically should only
3277 * occur for text relocations.
3278 */
3279 rc = file_has_perm(cred, vma->vm_file, FILE__EXECMOD);
3280 }
3281 if (rc)
3282 return rc;
3283 }
3284
3285 return file_map_prot_check(vma->vm_file, prot, vma->vm_flags&VM_SHARED);
3286}
3287
3288static int selinux_file_lock(struct file *file, unsigned int cmd)
3289{
3290 const struct cred *cred = current_cred();
3291
3292 return file_has_perm(cred, file, FILE__LOCK);
3293}
3294
3295static int selinux_file_fcntl(struct file *file, unsigned int cmd,
3296 unsigned long arg)
3297{
3298 const struct cred *cred = current_cred();
3299 int err = 0;
3300
3301 switch (cmd) {
3302 case F_SETFL:
3303 if ((file->f_flags & O_APPEND) && !(arg & O_APPEND)) {
3304 err = file_has_perm(cred, file, FILE__WRITE);
3305 break;
3306 }
3307 /* fall through */
3308 case F_SETOWN:
3309 case F_SETSIG:
3310 case F_GETFL:
3311 case F_GETOWN:
3312 case F_GETSIG:
3313 case F_GETOWNER_UIDS:
3314 /* Just check FD__USE permission */
3315 err = file_has_perm(cred, file, 0);
3316 break;
3317 case F_GETLK:
3318 case F_SETLK:
3319 case F_SETLKW:
3320 case F_OFD_GETLK:
3321 case F_OFD_SETLK:
3322 case F_OFD_SETLKW:
3323#if BITS_PER_LONG == 32
3324 case F_GETLK64:
3325 case F_SETLK64:
3326 case F_SETLKW64:
3327#endif
3328 err = file_has_perm(cred, file, FILE__LOCK);
3329 break;
3330 }
3331
3332 return err;
3333}
3334
3335static int selinux_file_set_fowner(struct file *file)
3336{
3337 struct file_security_struct *fsec;
3338
3339 fsec = file->f_security;
3340 fsec->fown_sid = current_sid();
3341
3342 return 0;
3343}
3344
3345static int selinux_file_send_sigiotask(struct task_struct *tsk,
3346 struct fown_struct *fown, int signum)
3347{
3348 struct file *file;
3349 u32 sid = task_sid(tsk);
3350 u32 perm;
3351 struct file_security_struct *fsec;
3352
3353 /* struct fown_struct is never outside the context of a struct file */
3354 file = container_of(fown, struct file, f_owner);
3355
3356 fsec = file->f_security;
3357
3358 if (!signum)
3359 perm = signal_to_av(SIGIO); /* as per send_sigio_to_task */
3360 else
3361 perm = signal_to_av(signum);
3362
3363 return avc_has_perm(fsec->fown_sid, sid,
3364 SECCLASS_PROCESS, perm, NULL);
3365}
3366
3367static int selinux_file_receive(struct file *file)
3368{
3369 const struct cred *cred = current_cred();
3370
3371 return file_has_perm(cred, file, file_to_av(file));
3372}
3373
3374static int selinux_file_open(struct file *file, const struct cred *cred)
3375{
3376 struct file_security_struct *fsec;
3377 struct inode_security_struct *isec;
3378
3379 fsec = file->f_security;
3380 isec = file_inode(file)->i_security;
3381 /*
3382 * Save inode label and policy sequence number
3383 * at open-time so that selinux_file_permission
3384 * can determine whether revalidation is necessary.
3385 * Task label is already saved in the file security
3386 * struct as its SID.
3387 */
3388 fsec->isid = isec->sid;
3389 fsec->pseqno = avc_policy_seqno();
3390 /*
3391 * Since the inode label or policy seqno may have changed
3392 * between the selinux_inode_permission check and the saving
3393 * of state above, recheck that access is still permitted.
3394 * Otherwise, access might never be revalidated against the
3395 * new inode label or new policy.
3396 * This check is not redundant - do not remove.
3397 */
3398 return file_path_has_perm(cred, file, open_file_to_av(file));
3399}
3400
3401/* task security operations */
3402
3403static int selinux_task_create(unsigned long clone_flags)
3404{
3405 return current_has_perm(current, PROCESS__FORK);
3406}
3407
3408/*
3409 * allocate the SELinux part of blank credentials
3410 */
3411static int selinux_cred_alloc_blank(struct cred *cred, gfp_t gfp)
3412{
3413 struct task_security_struct *tsec;
3414
3415 tsec = kzalloc(sizeof(struct task_security_struct), gfp);
3416 if (!tsec)
3417 return -ENOMEM;
3418
3419 cred->security = tsec;
3420 return 0;
3421}
3422
3423/*
3424 * detach and free the LSM part of a set of credentials
3425 */
3426static void selinux_cred_free(struct cred *cred)
3427{
3428 struct task_security_struct *tsec = cred->security;
3429
3430 /*
3431 * cred->security == NULL if security_cred_alloc_blank() or
3432 * security_prepare_creds() returned an error.
3433 */
3434 BUG_ON(cred->security && (unsigned long) cred->security < PAGE_SIZE);
3435 cred->security = (void *) 0x7UL;
3436 kfree(tsec);
3437}
3438
3439/*
3440 * prepare a new set of credentials for modification
3441 */
3442static int selinux_cred_prepare(struct cred *new, const struct cred *old,
3443 gfp_t gfp)
3444{
3445 const struct task_security_struct *old_tsec;
3446 struct task_security_struct *tsec;
3447
3448 old_tsec = old->security;
3449
3450 tsec = kmemdup(old_tsec, sizeof(struct task_security_struct), gfp);
3451 if (!tsec)
3452 return -ENOMEM;
3453
3454 new->security = tsec;
3455 return 0;
3456}
3457
3458/*
3459 * transfer the SELinux data to a blank set of creds
3460 */
3461static void selinux_cred_transfer(struct cred *new, const struct cred *old)
3462{
3463 const struct task_security_struct *old_tsec = old->security;
3464 struct task_security_struct *tsec = new->security;
3465
3466 *tsec = *old_tsec;
3467}
3468
3469/*
3470 * set the security data for a kernel service
3471 * - all the creation contexts are set to unlabelled
3472 */
3473static int selinux_kernel_act_as(struct cred *new, u32 secid)
3474{
3475 struct task_security_struct *tsec = new->security;
3476 u32 sid = current_sid();
3477 int ret;
3478
3479 ret = avc_has_perm(sid, secid,
3480 SECCLASS_KERNEL_SERVICE,
3481 KERNEL_SERVICE__USE_AS_OVERRIDE,
3482 NULL);
3483 if (ret == 0) {
3484 tsec->sid = secid;
3485 tsec->create_sid = 0;
3486 tsec->keycreate_sid = 0;
3487 tsec->sockcreate_sid = 0;
3488 }
3489 return ret;
3490}
3491
3492/*
3493 * set the file creation context in a security record to the same as the
3494 * objective context of the specified inode
3495 */
3496static int selinux_kernel_create_files_as(struct cred *new, struct inode *inode)
3497{
3498 struct inode_security_struct *isec = inode->i_security;
3499 struct task_security_struct *tsec = new->security;
3500 u32 sid = current_sid();
3501 int ret;
3502
3503 ret = avc_has_perm(sid, isec->sid,
3504 SECCLASS_KERNEL_SERVICE,
3505 KERNEL_SERVICE__CREATE_FILES_AS,
3506 NULL);
3507
3508 if (ret == 0)
3509 tsec->create_sid = isec->sid;
3510 return ret;
3511}
3512
3513static int selinux_kernel_module_request(char *kmod_name)
3514{
3515 u32 sid;
3516 struct common_audit_data ad;
3517
3518 sid = task_sid(current);
3519
3520 ad.type = LSM_AUDIT_DATA_KMOD;
3521 ad.u.kmod_name = kmod_name;
3522
3523 return avc_has_perm(sid, SECINITSID_KERNEL, SECCLASS_SYSTEM,
3524 SYSTEM__MODULE_REQUEST, &ad);
3525}
3526
3527static int selinux_task_setpgid(struct task_struct *p, pid_t pgid)
3528{
3529 return current_has_perm(p, PROCESS__SETPGID);
3530}
3531
3532static int selinux_task_getpgid(struct task_struct *p)
3533{
3534 return current_has_perm(p, PROCESS__GETPGID);
3535}
3536
3537static int selinux_task_getsid(struct task_struct *p)
3538{
3539 return current_has_perm(p, PROCESS__GETSESSION);
3540}
3541
3542static void selinux_task_getsecid(struct task_struct *p, u32 *secid)
3543{
3544 *secid = task_sid(p);
3545}
3546
3547static int selinux_task_setnice(struct task_struct *p, int nice)
3548{
3549 int rc;
3550
3551 rc = cap_task_setnice(p, nice);
3552 if (rc)
3553 return rc;
3554
3555 return current_has_perm(p, PROCESS__SETSCHED);
3556}
3557
3558static int selinux_task_setioprio(struct task_struct *p, int ioprio)
3559{
3560 int rc;
3561
3562 rc = cap_task_setioprio(p, ioprio);
3563 if (rc)
3564 return rc;
3565
3566 return current_has_perm(p, PROCESS__SETSCHED);
3567}
3568
3569static int selinux_task_getioprio(struct task_struct *p)
3570{
3571 return current_has_perm(p, PROCESS__GETSCHED);
3572}
3573
3574static int selinux_task_setrlimit(struct task_struct *p, unsigned int resource,
3575 struct rlimit *new_rlim)
3576{
3577 struct rlimit *old_rlim = p->signal->rlim + resource;
3578
3579 /* Control the ability to change the hard limit (whether
3580 lowering or raising it), so that the hard limit can
3581 later be used as a safe reset point for the soft limit
3582 upon context transitions. See selinux_bprm_committing_creds. */
3583 if (old_rlim->rlim_max != new_rlim->rlim_max)
3584 return current_has_perm(p, PROCESS__SETRLIMIT);
3585
3586 return 0;
3587}
3588
3589static int selinux_task_setscheduler(struct task_struct *p)
3590{
3591 int rc;
3592
3593 rc = cap_task_setscheduler(p);
3594 if (rc)
3595 return rc;
3596
3597 return current_has_perm(p, PROCESS__SETSCHED);
3598}
3599
3600static int selinux_task_getscheduler(struct task_struct *p)
3601{
3602 return current_has_perm(p, PROCESS__GETSCHED);
3603}
3604
3605static int selinux_task_movememory(struct task_struct *p)
3606{
3607 return current_has_perm(p, PROCESS__SETSCHED);
3608}
3609
3610static int selinux_task_kill(struct task_struct *p, struct siginfo *info,
3611 int sig, u32 secid)
3612{
3613 u32 perm;
3614 int rc;
3615
3616 if (!sig)
3617 perm = PROCESS__SIGNULL; /* null signal; existence test */
3618 else
3619 perm = signal_to_av(sig);
3620 if (secid)
3621 rc = avc_has_perm(secid, task_sid(p),
3622 SECCLASS_PROCESS, perm, NULL);
3623 else
3624 rc = current_has_perm(p, perm);
3625 return rc;
3626}
3627
3628static int selinux_task_wait(struct task_struct *p)
3629{
3630 return task_has_perm(p, current, PROCESS__SIGCHLD);
3631}
3632
3633static void selinux_task_to_inode(struct task_struct *p,
3634 struct inode *inode)
3635{
3636 struct inode_security_struct *isec = inode->i_security;
3637 u32 sid = task_sid(p);
3638
3639 isec->sid = sid;
3640 isec->initialized = 1;
3641}
3642
3643/* Returns error only if unable to parse addresses */
3644static int selinux_parse_skb_ipv4(struct sk_buff *skb,
3645 struct common_audit_data *ad, u8 *proto)
3646{
3647 int offset, ihlen, ret = -EINVAL;
3648 struct iphdr _iph, *ih;
3649
3650 offset = skb_network_offset(skb);
3651 ih = skb_header_pointer(skb, offset, sizeof(_iph), &_iph);
3652 if (ih == NULL)
3653 goto out;
3654
3655 ihlen = ih->ihl * 4;
3656 if (ihlen < sizeof(_iph))
3657 goto out;
3658
3659 ad->u.net->v4info.saddr = ih->saddr;
3660 ad->u.net->v4info.daddr = ih->daddr;
3661 ret = 0;
3662
3663 if (proto)
3664 *proto = ih->protocol;
3665
3666 switch (ih->protocol) {
3667 case IPPROTO_TCP: {
3668 struct tcphdr _tcph, *th;
3669
3670 if (ntohs(ih->frag_off) & IP_OFFSET)
3671 break;
3672
3673 offset += ihlen;
3674 th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph);
3675 if (th == NULL)
3676 break;
3677
3678 ad->u.net->sport = th->source;
3679 ad->u.net->dport = th->dest;
3680 break;
3681 }
3682
3683 case IPPROTO_UDP: {
3684 struct udphdr _udph, *uh;
3685
3686 if (ntohs(ih->frag_off) & IP_OFFSET)
3687 break;
3688
3689 offset += ihlen;
3690 uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph);
3691 if (uh == NULL)
3692 break;
3693
3694 ad->u.net->sport = uh->source;
3695 ad->u.net->dport = uh->dest;
3696 break;
3697 }
3698
3699 case IPPROTO_DCCP: {
3700 struct dccp_hdr _dccph, *dh;
3701
3702 if (ntohs(ih->frag_off) & IP_OFFSET)
3703 break;
3704
3705 offset += ihlen;
3706 dh = skb_header_pointer(skb, offset, sizeof(_dccph), &_dccph);
3707 if (dh == NULL)
3708 break;
3709
3710 ad->u.net->sport = dh->dccph_sport;
3711 ad->u.net->dport = dh->dccph_dport;
3712 break;
3713 }
3714
3715 default:
3716 break;
3717 }
3718out:
3719 return ret;
3720}
3721
3722#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
3723
3724/* Returns error only if unable to parse addresses */
3725static int selinux_parse_skb_ipv6(struct sk_buff *skb,
3726 struct common_audit_data *ad, u8 *proto)
3727{
3728 u8 nexthdr;
3729 int ret = -EINVAL, offset;
3730 struct ipv6hdr _ipv6h, *ip6;
3731 __be16 frag_off;
3732
3733 offset = skb_network_offset(skb);
3734 ip6 = skb_header_pointer(skb, offset, sizeof(_ipv6h), &_ipv6h);
3735 if (ip6 == NULL)
3736 goto out;
3737
3738 ad->u.net->v6info.saddr = ip6->saddr;
3739 ad->u.net->v6info.daddr = ip6->daddr;
3740 ret = 0;
3741
3742 nexthdr = ip6->nexthdr;
3743 offset += sizeof(_ipv6h);
3744 offset = ipv6_skip_exthdr(skb, offset, &nexthdr, &frag_off);
3745 if (offset < 0)
3746 goto out;
3747
3748 if (proto)
3749 *proto = nexthdr;
3750
3751 switch (nexthdr) {
3752 case IPPROTO_TCP: {
3753 struct tcphdr _tcph, *th;
3754
3755 th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph);
3756 if (th == NULL)
3757 break;
3758
3759 ad->u.net->sport = th->source;
3760 ad->u.net->dport = th->dest;
3761 break;
3762 }
3763
3764 case IPPROTO_UDP: {
3765 struct udphdr _udph, *uh;
3766
3767 uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph);
3768 if (uh == NULL)
3769 break;
3770
3771 ad->u.net->sport = uh->source;
3772 ad->u.net->dport = uh->dest;
3773 break;
3774 }
3775
3776 case IPPROTO_DCCP: {
3777 struct dccp_hdr _dccph, *dh;
3778
3779 dh = skb_header_pointer(skb, offset, sizeof(_dccph), &_dccph);
3780 if (dh == NULL)
3781 break;
3782
3783 ad->u.net->sport = dh->dccph_sport;
3784 ad->u.net->dport = dh->dccph_dport;
3785 break;
3786 }
3787
3788 /* includes fragments */
3789 default:
3790 break;
3791 }
3792out:
3793 return ret;
3794}
3795
3796#endif /* IPV6 */
3797
3798static int selinux_parse_skb(struct sk_buff *skb, struct common_audit_data *ad,
3799 char **_addrp, int src, u8 *proto)
3800{
3801 char *addrp;
3802 int ret;
3803
3804 switch (ad->u.net->family) {
3805 case PF_INET:
3806 ret = selinux_parse_skb_ipv4(skb, ad, proto);
3807 if (ret)
3808 goto parse_error;
3809 addrp = (char *)(src ? &ad->u.net->v4info.saddr :
3810 &ad->u.net->v4info.daddr);
3811 goto okay;
3812
3813#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
3814 case PF_INET6:
3815 ret = selinux_parse_skb_ipv6(skb, ad, proto);
3816 if (ret)
3817 goto parse_error;
3818 addrp = (char *)(src ? &ad->u.net->v6info.saddr :
3819 &ad->u.net->v6info.daddr);
3820 goto okay;
3821#endif /* IPV6 */
3822 default:
3823 addrp = NULL;
3824 goto okay;
3825 }
3826
3827parse_error:
3828 printk(KERN_WARNING
3829 "SELinux: failure in selinux_parse_skb(),"
3830 " unable to parse packet\n");
3831 return ret;
3832
3833okay:
3834 if (_addrp)
3835 *_addrp = addrp;
3836 return 0;
3837}
3838
3839/**
3840 * selinux_skb_peerlbl_sid - Determine the peer label of a packet
3841 * @skb: the packet
3842 * @family: protocol family
3843 * @sid: the packet's peer label SID
3844 *
3845 * Description:
3846 * Check the various different forms of network peer labeling and determine
3847 * the peer label/SID for the packet; most of the magic actually occurs in
3848 * the security server function security_net_peersid_cmp(). The function
3849 * returns zero if the value in @sid is valid (although it may be SECSID_NULL)
3850 * or -EACCES if @sid is invalid due to inconsistencies with the different
3851 * peer labels.
3852 *
3853 */
3854static int selinux_skb_peerlbl_sid(struct sk_buff *skb, u16 family, u32 *sid)
3855{
3856 int err;
3857 u32 xfrm_sid;
3858 u32 nlbl_sid;
3859 u32 nlbl_type;
3860
3861 err = selinux_xfrm_skb_sid(skb, &xfrm_sid);
3862 if (unlikely(err))
3863 return -EACCES;
3864 err = selinux_netlbl_skbuff_getsid(skb, family, &nlbl_type, &nlbl_sid);
3865 if (unlikely(err))
3866 return -EACCES;
3867
3868 err = security_net_peersid_resolve(nlbl_sid, nlbl_type, xfrm_sid, sid);
3869 if (unlikely(err)) {
3870 printk(KERN_WARNING
3871 "SELinux: failure in selinux_skb_peerlbl_sid(),"
3872 " unable to determine packet's peer label\n");
3873 return -EACCES;
3874 }
3875
3876 return 0;
3877}
3878
3879/**
3880 * selinux_conn_sid - Determine the child socket label for a connection
3881 * @sk_sid: the parent socket's SID
3882 * @skb_sid: the packet's SID
3883 * @conn_sid: the resulting connection SID
3884 *
3885 * If @skb_sid is valid then the user:role:type information from @sk_sid is
3886 * combined with the MLS information from @skb_sid in order to create
3887 * @conn_sid. If @skb_sid is not valid then then @conn_sid is simply a copy
3888 * of @sk_sid. Returns zero on success, negative values on failure.
3889 *
3890 */
3891static int selinux_conn_sid(u32 sk_sid, u32 skb_sid, u32 *conn_sid)
3892{
3893 int err = 0;
3894
3895 if (skb_sid != SECSID_NULL)
3896 err = security_sid_mls_copy(sk_sid, skb_sid, conn_sid);
3897 else
3898 *conn_sid = sk_sid;
3899
3900 return err;
3901}
3902
3903/* socket security operations */
3904
3905static int socket_sockcreate_sid(const struct task_security_struct *tsec,
3906 u16 secclass, u32 *socksid)
3907{
3908 if (tsec->sockcreate_sid > SECSID_NULL) {
3909 *socksid = tsec->sockcreate_sid;
3910 return 0;
3911 }
3912
3913 return security_transition_sid(tsec->sid, tsec->sid, secclass, NULL,
3914 socksid);
3915}
3916
3917static int sock_has_perm(struct task_struct *task, struct sock *sk, u32 perms)
3918{
3919 struct sk_security_struct *sksec = sk->sk_security;
3920 struct common_audit_data ad;
3921 struct lsm_network_audit net = {0,};
3922 u32 tsid = task_sid(task);
3923
3924 if (sksec->sid == SECINITSID_KERNEL)
3925 return 0;
3926
3927 ad.type = LSM_AUDIT_DATA_NET;
3928 ad.u.net = &net;
3929 ad.u.net->sk = sk;
3930
3931 return avc_has_perm(tsid, sksec->sid, sksec->sclass, perms, &ad);
3932}
3933
3934static int selinux_socket_create(int family, int type,
3935 int protocol, int kern)
3936{
3937 const struct task_security_struct *tsec = current_security();
3938 u32 newsid;
3939 u16 secclass;
3940 int rc;
3941
3942 if (kern)
3943 return 0;
3944
3945 secclass = socket_type_to_security_class(family, type, protocol);
3946 rc = socket_sockcreate_sid(tsec, secclass, &newsid);
3947 if (rc)
3948 return rc;
3949
3950 return avc_has_perm(tsec->sid, newsid, secclass, SOCKET__CREATE, NULL);
3951}
3952
3953static int selinux_socket_post_create(struct socket *sock, int family,
3954 int type, int protocol, int kern)
3955{
3956 const struct task_security_struct *tsec = current_security();
3957 struct inode_security_struct *isec = SOCK_INODE(sock)->i_security;
3958 struct sk_security_struct *sksec;
3959 int err = 0;
3960
3961 isec->sclass = socket_type_to_security_class(family, type, protocol);
3962
3963 if (kern)
3964 isec->sid = SECINITSID_KERNEL;
3965 else {
3966 err = socket_sockcreate_sid(tsec, isec->sclass, &(isec->sid));
3967 if (err)
3968 return err;
3969 }
3970
3971 isec->initialized = 1;
3972
3973 if (sock->sk) {
3974 sksec = sock->sk->sk_security;
3975 sksec->sid = isec->sid;
3976 sksec->sclass = isec->sclass;
3977 err = selinux_netlbl_socket_post_create(sock->sk, family);
3978 }
3979
3980 return err;
3981}
3982
3983/* Range of port numbers used to automatically bind.
3984 Need to determine whether we should perform a name_bind
3985 permission check between the socket and the port number. */
3986
3987static int selinux_socket_bind(struct socket *sock, struct sockaddr *address, int addrlen)
3988{
3989 struct sock *sk = sock->sk;
3990 u16 family;
3991 int err;
3992
3993 err = sock_has_perm(current, sk, SOCKET__BIND);
3994 if (err)
3995 goto out;
3996
3997 /*
3998 * If PF_INET or PF_INET6, check name_bind permission for the port.
3999 * Multiple address binding for SCTP is not supported yet: we just
4000 * check the first address now.
4001 */
4002 family = sk->sk_family;
4003 if (family == PF_INET || family == PF_INET6) {
4004 char *addrp;
4005 struct sk_security_struct *sksec = sk->sk_security;
4006 struct common_audit_data ad;
4007 struct lsm_network_audit net = {0,};
4008 struct sockaddr_in *addr4 = NULL;
4009 struct sockaddr_in6 *addr6 = NULL;
4010 unsigned short snum;
4011 u32 sid, node_perm;
4012
4013 if (family == PF_INET) {
4014 addr4 = (struct sockaddr_in *)address;
4015 snum = ntohs(addr4->sin_port);
4016 addrp = (char *)&addr4->sin_addr.s_addr;
4017 } else {
4018 addr6 = (struct sockaddr_in6 *)address;
4019 snum = ntohs(addr6->sin6_port);
4020 addrp = (char *)&addr6->sin6_addr.s6_addr;
4021 }
4022
4023 if (snum) {
4024 int low, high;
4025
4026 inet_get_local_port_range(sock_net(sk), &low, &high);
4027
4028 if (snum < max(PROT_SOCK, low) || snum > high) {
4029 err = sel_netport_sid(sk->sk_protocol,
4030 snum, &sid);
4031 if (err)
4032 goto out;
4033 ad.type = LSM_AUDIT_DATA_NET;
4034 ad.u.net = &net;
4035 ad.u.net->sport = htons(snum);
4036 ad.u.net->family = family;
4037 err = avc_has_perm(sksec->sid, sid,
4038 sksec->sclass,
4039 SOCKET__NAME_BIND, &ad);
4040 if (err)
4041 goto out;
4042 }
4043 }
4044
4045 switch (sksec->sclass) {
4046 case SECCLASS_TCP_SOCKET:
4047 node_perm = TCP_SOCKET__NODE_BIND;
4048 break;
4049
4050 case SECCLASS_UDP_SOCKET:
4051 node_perm = UDP_SOCKET__NODE_BIND;
4052 break;
4053
4054 case SECCLASS_DCCP_SOCKET:
4055 node_perm = DCCP_SOCKET__NODE_BIND;
4056 break;
4057
4058 default:
4059 node_perm = RAWIP_SOCKET__NODE_BIND;
4060 break;
4061 }
4062
4063 err = sel_netnode_sid(addrp, family, &sid);
4064 if (err)
4065 goto out;
4066
4067 ad.type = LSM_AUDIT_DATA_NET;
4068 ad.u.net = &net;
4069 ad.u.net->sport = htons(snum);
4070 ad.u.net->family = family;
4071
4072 if (family == PF_INET)
4073 ad.u.net->v4info.saddr = addr4->sin_addr.s_addr;
4074 else
4075 ad.u.net->v6info.saddr = addr6->sin6_addr;
4076
4077 err = avc_has_perm(sksec->sid, sid,
4078 sksec->sclass, node_perm, &ad);
4079 if (err)
4080 goto out;
4081 }
4082out:
4083 return err;
4084}
4085
4086static int selinux_socket_connect(struct socket *sock, struct sockaddr *address, int addrlen)
4087{
4088 struct sock *sk = sock->sk;
4089 struct sk_security_struct *sksec = sk->sk_security;
4090 int err;
4091
4092 err = sock_has_perm(current, sk, SOCKET__CONNECT);
4093 if (err)
4094 return err;
4095
4096 /*
4097 * If a TCP or DCCP socket, check name_connect permission for the port.
4098 */
4099 if (sksec->sclass == SECCLASS_TCP_SOCKET ||
4100 sksec->sclass == SECCLASS_DCCP_SOCKET) {
4101 struct common_audit_data ad;
4102 struct lsm_network_audit net = {0,};
4103 struct sockaddr_in *addr4 = NULL;
4104 struct sockaddr_in6 *addr6 = NULL;
4105 unsigned short snum;
4106 u32 sid, perm;
4107
4108 if (sk->sk_family == PF_INET) {
4109 addr4 = (struct sockaddr_in *)address;
4110 if (addrlen < sizeof(struct sockaddr_in))
4111 return -EINVAL;
4112 snum = ntohs(addr4->sin_port);
4113 } else {
4114 addr6 = (struct sockaddr_in6 *)address;
4115 if (addrlen < SIN6_LEN_RFC2133)
4116 return -EINVAL;
4117 snum = ntohs(addr6->sin6_port);
4118 }
4119
4120 err = sel_netport_sid(sk->sk_protocol, snum, &sid);
4121 if (err)
4122 goto out;
4123
4124 perm = (sksec->sclass == SECCLASS_TCP_SOCKET) ?
4125 TCP_SOCKET__NAME_CONNECT : DCCP_SOCKET__NAME_CONNECT;
4126
4127 ad.type = LSM_AUDIT_DATA_NET;
4128 ad.u.net = &net;
4129 ad.u.net->dport = htons(snum);
4130 ad.u.net->family = sk->sk_family;
4131 err = avc_has_perm(sksec->sid, sid, sksec->sclass, perm, &ad);
4132 if (err)
4133 goto out;
4134 }
4135
4136 err = selinux_netlbl_socket_connect(sk, address);
4137
4138out:
4139 return err;
4140}
4141
4142static int selinux_socket_listen(struct socket *sock, int backlog)
4143{
4144 return sock_has_perm(current, sock->sk, SOCKET__LISTEN);
4145}
4146
4147static int selinux_socket_accept(struct socket *sock, struct socket *newsock)
4148{
4149 int err;
4150 struct inode_security_struct *isec;
4151 struct inode_security_struct *newisec;
4152
4153 err = sock_has_perm(current, sock->sk, SOCKET__ACCEPT);
4154 if (err)
4155 return err;
4156
4157 newisec = SOCK_INODE(newsock)->i_security;
4158
4159 isec = SOCK_INODE(sock)->i_security;
4160 newisec->sclass = isec->sclass;
4161 newisec->sid = isec->sid;
4162 newisec->initialized = 1;
4163
4164 return 0;
4165}
4166
4167static int selinux_socket_sendmsg(struct socket *sock, struct msghdr *msg,
4168 int size)
4169{
4170 return sock_has_perm(current, sock->sk, SOCKET__WRITE);
4171}
4172
4173static int selinux_socket_recvmsg(struct socket *sock, struct msghdr *msg,
4174 int size, int flags)
4175{
4176 return sock_has_perm(current, sock->sk, SOCKET__READ);
4177}
4178
4179static int selinux_socket_getsockname(struct socket *sock)
4180{
4181 return sock_has_perm(current, sock->sk, SOCKET__GETATTR);
4182}
4183
4184static int selinux_socket_getpeername(struct socket *sock)
4185{
4186 return sock_has_perm(current, sock->sk, SOCKET__GETATTR);
4187}
4188
4189static int selinux_socket_setsockopt(struct socket *sock, int level, int optname)
4190{
4191 int err;
4192
4193 err = sock_has_perm(current, sock->sk, SOCKET__SETOPT);
4194 if (err)
4195 return err;
4196
4197 return selinux_netlbl_socket_setsockopt(sock, level, optname);
4198}
4199
4200static int selinux_socket_getsockopt(struct socket *sock, int level,
4201 int optname)
4202{
4203 return sock_has_perm(current, sock->sk, SOCKET__GETOPT);
4204}
4205
4206static int selinux_socket_shutdown(struct socket *sock, int how)
4207{
4208 return sock_has_perm(current, sock->sk, SOCKET__SHUTDOWN);
4209}
4210
4211static int selinux_socket_unix_stream_connect(struct sock *sock,
4212 struct sock *other,
4213 struct sock *newsk)
4214{
4215 struct sk_security_struct *sksec_sock = sock->sk_security;
4216 struct sk_security_struct *sksec_other = other->sk_security;
4217 struct sk_security_struct *sksec_new = newsk->sk_security;
4218 struct common_audit_data ad;
4219 struct lsm_network_audit net = {0,};
4220 int err;
4221
4222 ad.type = LSM_AUDIT_DATA_NET;
4223 ad.u.net = &net;
4224 ad.u.net->sk = other;
4225
4226 err = avc_has_perm(sksec_sock->sid, sksec_other->sid,
4227 sksec_other->sclass,
4228 UNIX_STREAM_SOCKET__CONNECTTO, &ad);
4229 if (err)
4230 return err;
4231
4232 /* server child socket */
4233 sksec_new->peer_sid = sksec_sock->sid;
4234 err = security_sid_mls_copy(sksec_other->sid, sksec_sock->sid,
4235 &sksec_new->sid);
4236 if (err)
4237 return err;
4238
4239 /* connecting socket */
4240 sksec_sock->peer_sid = sksec_new->sid;
4241
4242 return 0;
4243}
4244
4245static int selinux_socket_unix_may_send(struct socket *sock,
4246 struct socket *other)
4247{
4248 struct sk_security_struct *ssec = sock->sk->sk_security;
4249 struct sk_security_struct *osec = other->sk->sk_security;
4250 struct common_audit_data ad;
4251 struct lsm_network_audit net = {0,};
4252
4253 ad.type = LSM_AUDIT_DATA_NET;
4254 ad.u.net = &net;
4255 ad.u.net->sk = other->sk;
4256
4257 return avc_has_perm(ssec->sid, osec->sid, osec->sclass, SOCKET__SENDTO,
4258 &ad);
4259}
4260
4261static int selinux_inet_sys_rcv_skb(int ifindex, char *addrp, u16 family,
4262 u32 peer_sid,
4263 struct common_audit_data *ad)
4264{
4265 int err;
4266 u32 if_sid;
4267 u32 node_sid;
4268
4269 err = sel_netif_sid(ifindex, &if_sid);
4270 if (err)
4271 return err;
4272 err = avc_has_perm(peer_sid, if_sid,
4273 SECCLASS_NETIF, NETIF__INGRESS, ad);
4274 if (err)
4275 return err;
4276
4277 err = sel_netnode_sid(addrp, family, &node_sid);
4278 if (err)
4279 return err;
4280 return avc_has_perm(peer_sid, node_sid,
4281 SECCLASS_NODE, NODE__RECVFROM, ad);
4282}
4283
4284static int selinux_sock_rcv_skb_compat(struct sock *sk, struct sk_buff *skb,
4285 u16 family)
4286{
4287 int err = 0;
4288 struct sk_security_struct *sksec = sk->sk_security;
4289 u32 sk_sid = sksec->sid;
4290 struct common_audit_data ad;
4291 struct lsm_network_audit net = {0,};
4292 char *addrp;
4293
4294 ad.type = LSM_AUDIT_DATA_NET;
4295 ad.u.net = &net;
4296 ad.u.net->netif = skb->skb_iif;
4297 ad.u.net->family = family;
4298 err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL);
4299 if (err)
4300 return err;
4301
4302 if (selinux_secmark_enabled()) {
4303 err = avc_has_perm(sk_sid, skb->secmark, SECCLASS_PACKET,
4304 PACKET__RECV, &ad);
4305 if (err)
4306 return err;
4307 }
4308
4309 err = selinux_netlbl_sock_rcv_skb(sksec, skb, family, &ad);
4310 if (err)
4311 return err;
4312 err = selinux_xfrm_sock_rcv_skb(sksec->sid, skb, &ad);
4313
4314 return err;
4315}
4316
4317static int selinux_socket_sock_rcv_skb(struct sock *sk, struct sk_buff *skb)
4318{
4319 int err;
4320 struct sk_security_struct *sksec = sk->sk_security;
4321 u16 family = sk->sk_family;
4322 u32 sk_sid = sksec->sid;
4323 struct common_audit_data ad;
4324 struct lsm_network_audit net = {0,};
4325 char *addrp;
4326 u8 secmark_active;
4327 u8 peerlbl_active;
4328
4329 if (family != PF_INET && family != PF_INET6)
4330 return 0;
4331
4332 /* Handle mapped IPv4 packets arriving via IPv6 sockets */
4333 if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
4334 family = PF_INET;
4335
4336 /* If any sort of compatibility mode is enabled then handoff processing
4337 * to the selinux_sock_rcv_skb_compat() function to deal with the
4338 * special handling. We do this in an attempt to keep this function
4339 * as fast and as clean as possible. */
4340 if (!selinux_policycap_netpeer)
4341 return selinux_sock_rcv_skb_compat(sk, skb, family);
4342
4343 secmark_active = selinux_secmark_enabled();
4344 peerlbl_active = selinux_peerlbl_enabled();
4345 if (!secmark_active && !peerlbl_active)
4346 return 0;
4347
4348 ad.type = LSM_AUDIT_DATA_NET;
4349 ad.u.net = &net;
4350 ad.u.net->netif = skb->skb_iif;
4351 ad.u.net->family = family;
4352 err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL);
4353 if (err)
4354 return err;
4355
4356 if (peerlbl_active) {
4357 u32 peer_sid;
4358
4359 err = selinux_skb_peerlbl_sid(skb, family, &peer_sid);
4360 if (err)
4361 return err;
4362 err = selinux_inet_sys_rcv_skb(skb->skb_iif, addrp, family,
4363 peer_sid, &ad);
4364 if (err) {
4365 selinux_netlbl_err(skb, err, 0);
4366 return err;
4367 }
4368 err = avc_has_perm(sk_sid, peer_sid, SECCLASS_PEER,
4369 PEER__RECV, &ad);
4370 if (err) {
4371 selinux_netlbl_err(skb, err, 0);
4372 return err;
4373 }
4374 }
4375
4376 if (secmark_active) {
4377 err = avc_has_perm(sk_sid, skb->secmark, SECCLASS_PACKET,
4378 PACKET__RECV, &ad);
4379 if (err)
4380 return err;
4381 }
4382
4383 return err;
4384}
4385
4386static int selinux_socket_getpeersec_stream(struct socket *sock, char __user *optval,
4387 int __user *optlen, unsigned len)
4388{
4389 int err = 0;
4390 char *scontext;
4391 u32 scontext_len;
4392 struct sk_security_struct *sksec = sock->sk->sk_security;
4393 u32 peer_sid = SECSID_NULL;
4394
4395 if (sksec->sclass == SECCLASS_UNIX_STREAM_SOCKET ||
4396 sksec->sclass == SECCLASS_TCP_SOCKET)
4397 peer_sid = sksec->peer_sid;
4398 if (peer_sid == SECSID_NULL)
4399 return -ENOPROTOOPT;
4400
4401 err = security_sid_to_context(peer_sid, &scontext, &scontext_len);
4402 if (err)
4403 return err;
4404
4405 if (scontext_len > len) {
4406 err = -ERANGE;
4407 goto out_len;
4408 }
4409
4410 if (copy_to_user(optval, scontext, scontext_len))
4411 err = -EFAULT;
4412
4413out_len:
4414 if (put_user(scontext_len, optlen))
4415 err = -EFAULT;
4416 kfree(scontext);
4417 return err;
4418}
4419
4420static int selinux_socket_getpeersec_dgram(struct socket *sock, struct sk_buff *skb, u32 *secid)
4421{
4422 u32 peer_secid = SECSID_NULL;
4423 u16 family;
4424
4425 if (skb && skb->protocol == htons(ETH_P_IP))
4426 family = PF_INET;
4427 else if (skb && skb->protocol == htons(ETH_P_IPV6))
4428 family = PF_INET6;
4429 else if (sock)
4430 family = sock->sk->sk_family;
4431 else
4432 goto out;
4433
4434 if (sock && family == PF_UNIX)
4435 selinux_inode_getsecid(SOCK_INODE(sock), &peer_secid);
4436 else if (skb)
4437 selinux_skb_peerlbl_sid(skb, family, &peer_secid);
4438
4439out:
4440 *secid = peer_secid;
4441 if (peer_secid == SECSID_NULL)
4442 return -EINVAL;
4443 return 0;
4444}
4445
4446static int selinux_sk_alloc_security(struct sock *sk, int family, gfp_t priority)
4447{
4448 struct sk_security_struct *sksec;
4449
4450 sksec = kzalloc(sizeof(*sksec), priority);
4451 if (!sksec)
4452 return -ENOMEM;
4453
4454 sksec->peer_sid = SECINITSID_UNLABELED;
4455 sksec->sid = SECINITSID_UNLABELED;
4456 selinux_netlbl_sk_security_reset(sksec);
4457 sk->sk_security = sksec;
4458
4459 return 0;
4460}
4461
4462static void selinux_sk_free_security(struct sock *sk)
4463{
4464 struct sk_security_struct *sksec = sk->sk_security;
4465
4466 sk->sk_security = NULL;
4467 selinux_netlbl_sk_security_free(sksec);
4468 kfree(sksec);
4469}
4470
4471static void selinux_sk_clone_security(const struct sock *sk, struct sock *newsk)
4472{
4473 struct sk_security_struct *sksec = sk->sk_security;
4474 struct sk_security_struct *newsksec = newsk->sk_security;
4475
4476 newsksec->sid = sksec->sid;
4477 newsksec->peer_sid = sksec->peer_sid;
4478 newsksec->sclass = sksec->sclass;
4479
4480 selinux_netlbl_sk_security_reset(newsksec);
4481}
4482
4483static void selinux_sk_getsecid(struct sock *sk, u32 *secid)
4484{
4485 if (!sk)
4486 *secid = SECINITSID_ANY_SOCKET;
4487 else {
4488 struct sk_security_struct *sksec = sk->sk_security;
4489
4490 *secid = sksec->sid;
4491 }
4492}
4493
4494static void selinux_sock_graft(struct sock *sk, struct socket *parent)
4495{
4496 struct inode_security_struct *isec = SOCK_INODE(parent)->i_security;
4497 struct sk_security_struct *sksec = sk->sk_security;
4498
4499 if (sk->sk_family == PF_INET || sk->sk_family == PF_INET6 ||
4500 sk->sk_family == PF_UNIX)
4501 isec->sid = sksec->sid;
4502 sksec->sclass = isec->sclass;
4503}
4504
4505static int selinux_inet_conn_request(struct sock *sk, struct sk_buff *skb,
4506 struct request_sock *req)
4507{
4508 struct sk_security_struct *sksec = sk->sk_security;
4509 int err;
4510 u16 family = req->rsk_ops->family;
4511 u32 connsid;
4512 u32 peersid;
4513
4514 err = selinux_skb_peerlbl_sid(skb, family, &peersid);
4515 if (err)
4516 return err;
4517 err = selinux_conn_sid(sksec->sid, peersid, &connsid);
4518 if (err)
4519 return err;
4520 req->secid = connsid;
4521 req->peer_secid = peersid;
4522
4523 return selinux_netlbl_inet_conn_request(req, family);
4524}
4525
4526static void selinux_inet_csk_clone(struct sock *newsk,
4527 const struct request_sock *req)
4528{
4529 struct sk_security_struct *newsksec = newsk->sk_security;
4530
4531 newsksec->sid = req->secid;
4532 newsksec->peer_sid = req->peer_secid;
4533 /* NOTE: Ideally, we should also get the isec->sid for the
4534 new socket in sync, but we don't have the isec available yet.
4535 So we will wait until sock_graft to do it, by which
4536 time it will have been created and available. */
4537
4538 /* We don't need to take any sort of lock here as we are the only
4539 * thread with access to newsksec */
4540 selinux_netlbl_inet_csk_clone(newsk, req->rsk_ops->family);
4541}
4542
4543static void selinux_inet_conn_established(struct sock *sk, struct sk_buff *skb)
4544{
4545 u16 family = sk->sk_family;
4546 struct sk_security_struct *sksec = sk->sk_security;
4547
4548 /* handle mapped IPv4 packets arriving via IPv6 sockets */
4549 if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
4550 family = PF_INET;
4551
4552 selinux_skb_peerlbl_sid(skb, family, &sksec->peer_sid);
4553}
4554
4555static void selinux_skb_owned_by(struct sk_buff *skb, struct sock *sk)
4556{
4557 skb_set_owner_w(skb, sk);
4558}
4559
4560static int selinux_secmark_relabel_packet(u32 sid)
4561{
4562 const struct task_security_struct *__tsec;
4563 u32 tsid;
4564
4565 __tsec = current_security();
4566 tsid = __tsec->sid;
4567
4568 return avc_has_perm(tsid, sid, SECCLASS_PACKET, PACKET__RELABELTO, NULL);
4569}
4570
4571static void selinux_secmark_refcount_inc(void)
4572{
4573 atomic_inc(&selinux_secmark_refcount);
4574}
4575
4576static void selinux_secmark_refcount_dec(void)
4577{
4578 atomic_dec(&selinux_secmark_refcount);
4579}
4580
4581static void selinux_req_classify_flow(const struct request_sock *req,
4582 struct flowi *fl)
4583{
4584 fl->flowi_secid = req->secid;
4585}
4586
4587static int selinux_tun_dev_alloc_security(void **security)
4588{
4589 struct tun_security_struct *tunsec;
4590
4591 tunsec = kzalloc(sizeof(*tunsec), GFP_KERNEL);
4592 if (!tunsec)
4593 return -ENOMEM;
4594 tunsec->sid = current_sid();
4595
4596 *security = tunsec;
4597 return 0;
4598}
4599
4600static void selinux_tun_dev_free_security(void *security)
4601{
4602 kfree(security);
4603}
4604
4605static int selinux_tun_dev_create(void)
4606{
4607 u32 sid = current_sid();
4608
4609 /* we aren't taking into account the "sockcreate" SID since the socket
4610 * that is being created here is not a socket in the traditional sense,
4611 * instead it is a private sock, accessible only to the kernel, and
4612 * representing a wide range of network traffic spanning multiple
4613 * connections unlike traditional sockets - check the TUN driver to
4614 * get a better understanding of why this socket is special */
4615
4616 return avc_has_perm(sid, sid, SECCLASS_TUN_SOCKET, TUN_SOCKET__CREATE,
4617 NULL);
4618}
4619
4620static int selinux_tun_dev_attach_queue(void *security)
4621{
4622 struct tun_security_struct *tunsec = security;
4623
4624 return avc_has_perm(current_sid(), tunsec->sid, SECCLASS_TUN_SOCKET,
4625 TUN_SOCKET__ATTACH_QUEUE, NULL);
4626}
4627
4628static int selinux_tun_dev_attach(struct sock *sk, void *security)
4629{
4630 struct tun_security_struct *tunsec = security;
4631 struct sk_security_struct *sksec = sk->sk_security;
4632
4633 /* we don't currently perform any NetLabel based labeling here and it
4634 * isn't clear that we would want to do so anyway; while we could apply
4635 * labeling without the support of the TUN user the resulting labeled
4636 * traffic from the other end of the connection would almost certainly
4637 * cause confusion to the TUN user that had no idea network labeling
4638 * protocols were being used */
4639
4640 sksec->sid = tunsec->sid;
4641 sksec->sclass = SECCLASS_TUN_SOCKET;
4642
4643 return 0;
4644}
4645
4646static int selinux_tun_dev_open(void *security)
4647{
4648 struct tun_security_struct *tunsec = security;
4649 u32 sid = current_sid();
4650 int err;
4651
4652 err = avc_has_perm(sid, tunsec->sid, SECCLASS_TUN_SOCKET,
4653 TUN_SOCKET__RELABELFROM, NULL);
4654 if (err)
4655 return err;
4656 err = avc_has_perm(sid, sid, SECCLASS_TUN_SOCKET,
4657 TUN_SOCKET__RELABELTO, NULL);
4658 if (err)
4659 return err;
4660 tunsec->sid = sid;
4661
4662 return 0;
4663}
4664
4665static int selinux_nlmsg_perm(struct sock *sk, struct sk_buff *skb)
4666{
4667 int err = 0;
4668 u32 perm;
4669 struct nlmsghdr *nlh;
4670 struct sk_security_struct *sksec = sk->sk_security;
4671
4672 if (skb->len < NLMSG_HDRLEN) {
4673 err = -EINVAL;
4674 goto out;
4675 }
4676 nlh = nlmsg_hdr(skb);
4677
4678 err = selinux_nlmsg_lookup(sksec->sclass, nlh->nlmsg_type, &perm);
4679 if (err) {
4680 if (err == -EINVAL) {
4681 audit_log(current->audit_context, GFP_KERNEL, AUDIT_SELINUX_ERR,
4682 "SELinux: unrecognized netlink message"
4683 " type=%hu for sclass=%hu\n",
4684 nlh->nlmsg_type, sksec->sclass);
4685 if (!selinux_enforcing || security_get_allow_unknown())
4686 err = 0;
4687 }
4688
4689 /* Ignore */
4690 if (err == -ENOENT)
4691 err = 0;
4692 goto out;
4693 }
4694
4695 err = sock_has_perm(current, sk, perm);
4696out:
4697 return err;
4698}
4699
4700#ifdef CONFIG_NETFILTER
4701
4702static unsigned int selinux_ip_forward(struct sk_buff *skb, int ifindex,
4703 u16 family)
4704{
4705 int err;
4706 char *addrp;
4707 u32 peer_sid;
4708 struct common_audit_data ad;
4709 struct lsm_network_audit net = {0,};
4710 u8 secmark_active;
4711 u8 netlbl_active;
4712 u8 peerlbl_active;
4713
4714 if (!selinux_policycap_netpeer)
4715 return NF_ACCEPT;
4716
4717 secmark_active = selinux_secmark_enabled();
4718 netlbl_active = netlbl_enabled();
4719 peerlbl_active = selinux_peerlbl_enabled();
4720 if (!secmark_active && !peerlbl_active)
4721 return NF_ACCEPT;
4722
4723 if (selinux_skb_peerlbl_sid(skb, family, &peer_sid) != 0)
4724 return NF_DROP;
4725
4726 ad.type = LSM_AUDIT_DATA_NET;
4727 ad.u.net = &net;
4728 ad.u.net->netif = ifindex;
4729 ad.u.net->family = family;
4730 if (selinux_parse_skb(skb, &ad, &addrp, 1, NULL) != 0)
4731 return NF_DROP;
4732
4733 if (peerlbl_active) {
4734 err = selinux_inet_sys_rcv_skb(ifindex, addrp, family,
4735 peer_sid, &ad);
4736 if (err) {
4737 selinux_netlbl_err(skb, err, 1);
4738 return NF_DROP;
4739 }
4740 }
4741
4742 if (secmark_active)
4743 if (avc_has_perm(peer_sid, skb->secmark,
4744 SECCLASS_PACKET, PACKET__FORWARD_IN, &ad))
4745 return NF_DROP;
4746
4747 if (netlbl_active)
4748 /* we do this in the FORWARD path and not the POST_ROUTING
4749 * path because we want to make sure we apply the necessary
4750 * labeling before IPsec is applied so we can leverage AH
4751 * protection */
4752 if (selinux_netlbl_skbuff_setsid(skb, family, peer_sid) != 0)
4753 return NF_DROP;
4754
4755 return NF_ACCEPT;
4756}
4757
4758static unsigned int selinux_ipv4_forward(const struct nf_hook_ops *ops,
4759 struct sk_buff *skb,
4760 const struct net_device *in,
4761 const struct net_device *out,
4762 int (*okfn)(struct sk_buff *))
4763{
4764 return selinux_ip_forward(skb, in->ifindex, PF_INET);
4765}
4766
4767#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
4768static unsigned int selinux_ipv6_forward(const struct nf_hook_ops *ops,
4769 struct sk_buff *skb,
4770 const struct net_device *in,
4771 const struct net_device *out,
4772 int (*okfn)(struct sk_buff *))
4773{
4774 return selinux_ip_forward(skb, in->ifindex, PF_INET6);
4775}
4776#endif /* IPV6 */
4777
4778static unsigned int selinux_ip_output(struct sk_buff *skb,
4779 u16 family)
4780{
4781 struct sock *sk;
4782 u32 sid;
4783
4784 if (!netlbl_enabled())
4785 return NF_ACCEPT;
4786
4787 /* we do this in the LOCAL_OUT path and not the POST_ROUTING path
4788 * because we want to make sure we apply the necessary labeling
4789 * before IPsec is applied so we can leverage AH protection */
4790 sk = skb->sk;
4791 if (sk) {
4792 struct sk_security_struct *sksec;
4793
4794 if (sk->sk_state == TCP_LISTEN)
4795 /* if the socket is the listening state then this
4796 * packet is a SYN-ACK packet which means it needs to
4797 * be labeled based on the connection/request_sock and
4798 * not the parent socket. unfortunately, we can't
4799 * lookup the request_sock yet as it isn't queued on
4800 * the parent socket until after the SYN-ACK is sent.
4801 * the "solution" is to simply pass the packet as-is
4802 * as any IP option based labeling should be copied
4803 * from the initial connection request (in the IP
4804 * layer). it is far from ideal, but until we get a
4805 * security label in the packet itself this is the
4806 * best we can do. */
4807 return NF_ACCEPT;
4808
4809 /* standard practice, label using the parent socket */
4810 sksec = sk->sk_security;
4811 sid = sksec->sid;
4812 } else
4813 sid = SECINITSID_KERNEL;
4814 if (selinux_netlbl_skbuff_setsid(skb, family, sid) != 0)
4815 return NF_DROP;
4816
4817 return NF_ACCEPT;
4818}
4819
4820static unsigned int selinux_ipv4_output(const struct nf_hook_ops *ops,
4821 struct sk_buff *skb,
4822 const struct net_device *in,
4823 const struct net_device *out,
4824 int (*okfn)(struct sk_buff *))
4825{
4826 return selinux_ip_output(skb, PF_INET);
4827}
4828
4829static unsigned int selinux_ip_postroute_compat(struct sk_buff *skb,
4830 int ifindex,
4831 u16 family)
4832{
4833 struct sock *sk = skb->sk;
4834 struct sk_security_struct *sksec;
4835 struct common_audit_data ad;
4836 struct lsm_network_audit net = {0,};
4837 char *addrp;
4838 u8 proto;
4839
4840 if (sk == NULL)
4841 return NF_ACCEPT;
4842 sksec = sk->sk_security;
4843
4844 ad.type = LSM_AUDIT_DATA_NET;
4845 ad.u.net = &net;
4846 ad.u.net->netif = ifindex;
4847 ad.u.net->family = family;
4848 if (selinux_parse_skb(skb, &ad, &addrp, 0, &proto))
4849 return NF_DROP;
4850
4851 if (selinux_secmark_enabled())
4852 if (avc_has_perm(sksec->sid, skb->secmark,
4853 SECCLASS_PACKET, PACKET__SEND, &ad))
4854 return NF_DROP_ERR(-ECONNREFUSED);
4855
4856 if (selinux_xfrm_postroute_last(sksec->sid, skb, &ad, proto))
4857 return NF_DROP_ERR(-ECONNREFUSED);
4858
4859 return NF_ACCEPT;
4860}
4861
4862static unsigned int selinux_ip_postroute(struct sk_buff *skb, int ifindex,
4863 u16 family)
4864{
4865 u32 secmark_perm;
4866 u32 peer_sid;
4867 struct sock *sk;
4868 struct common_audit_data ad;
4869 struct lsm_network_audit net = {0,};
4870 char *addrp;
4871 u8 secmark_active;
4872 u8 peerlbl_active;
4873
4874 /* If any sort of compatibility mode is enabled then handoff processing
4875 * to the selinux_ip_postroute_compat() function to deal with the
4876 * special handling. We do this in an attempt to keep this function
4877 * as fast and as clean as possible. */
4878 if (!selinux_policycap_netpeer)
4879 return selinux_ip_postroute_compat(skb, ifindex, family);
4880
4881 secmark_active = selinux_secmark_enabled();
4882 peerlbl_active = selinux_peerlbl_enabled();
4883 if (!secmark_active && !peerlbl_active)
4884 return NF_ACCEPT;
4885
4886 sk = skb->sk;
4887
4888#ifdef CONFIG_XFRM
4889 /* If skb->dst->xfrm is non-NULL then the packet is undergoing an IPsec
4890 * packet transformation so allow the packet to pass without any checks
4891 * since we'll have another chance to perform access control checks
4892 * when the packet is on it's final way out.
4893 * NOTE: there appear to be some IPv6 multicast cases where skb->dst
4894 * is NULL, in this case go ahead and apply access control.
4895 * NOTE: if this is a local socket (skb->sk != NULL) that is in the
4896 * TCP listening state we cannot wait until the XFRM processing
4897 * is done as we will miss out on the SA label if we do;
4898 * unfortunately, this means more work, but it is only once per
4899 * connection. */
4900 if (skb_dst(skb) != NULL && skb_dst(skb)->xfrm != NULL &&
4901 !(sk != NULL && sk->sk_state == TCP_LISTEN))
4902 return NF_ACCEPT;
4903#endif
4904
4905 if (sk == NULL) {
4906 /* Without an associated socket the packet is either coming
4907 * from the kernel or it is being forwarded; check the packet
4908 * to determine which and if the packet is being forwarded
4909 * query the packet directly to determine the security label. */
4910 if (skb->skb_iif) {
4911 secmark_perm = PACKET__FORWARD_OUT;
4912 if (selinux_skb_peerlbl_sid(skb, family, &peer_sid))
4913 return NF_DROP;
4914 } else {
4915 secmark_perm = PACKET__SEND;
4916 peer_sid = SECINITSID_KERNEL;
4917 }
4918 } else if (sk->sk_state == TCP_LISTEN) {
4919 /* Locally generated packet but the associated socket is in the
4920 * listening state which means this is a SYN-ACK packet. In
4921 * this particular case the correct security label is assigned
4922 * to the connection/request_sock but unfortunately we can't
4923 * query the request_sock as it isn't queued on the parent
4924 * socket until after the SYN-ACK packet is sent; the only
4925 * viable choice is to regenerate the label like we do in
4926 * selinux_inet_conn_request(). See also selinux_ip_output()
4927 * for similar problems. */
4928 u32 skb_sid;
4929 struct sk_security_struct *sksec = sk->sk_security;
4930 if (selinux_skb_peerlbl_sid(skb, family, &skb_sid))
4931 return NF_DROP;
4932 /* At this point, if the returned skb peerlbl is SECSID_NULL
4933 * and the packet has been through at least one XFRM
4934 * transformation then we must be dealing with the "final"
4935 * form of labeled IPsec packet; since we've already applied
4936 * all of our access controls on this packet we can safely
4937 * pass the packet. */
4938 if (skb_sid == SECSID_NULL) {
4939 switch (family) {
4940 case PF_INET:
4941 if (IPCB(skb)->flags & IPSKB_XFRM_TRANSFORMED)
4942 return NF_ACCEPT;
4943 break;
4944 case PF_INET6:
4945 if (IP6CB(skb)->flags & IP6SKB_XFRM_TRANSFORMED)
4946 return NF_ACCEPT;
4947 default:
4948 return NF_DROP_ERR(-ECONNREFUSED);
4949 }
4950 }
4951 if (selinux_conn_sid(sksec->sid, skb_sid, &peer_sid))
4952 return NF_DROP;
4953 secmark_perm = PACKET__SEND;
4954 } else {
4955 /* Locally generated packet, fetch the security label from the
4956 * associated socket. */
4957 struct sk_security_struct *sksec = sk->sk_security;
4958 peer_sid = sksec->sid;
4959 secmark_perm = PACKET__SEND;
4960 }
4961
4962 ad.type = LSM_AUDIT_DATA_NET;
4963 ad.u.net = &net;
4964 ad.u.net->netif = ifindex;
4965 ad.u.net->family = family;
4966 if (selinux_parse_skb(skb, &ad, &addrp, 0, NULL))
4967 return NF_DROP;
4968
4969 if (secmark_active)
4970 if (avc_has_perm(peer_sid, skb->secmark,
4971 SECCLASS_PACKET, secmark_perm, &ad))
4972 return NF_DROP_ERR(-ECONNREFUSED);
4973
4974 if (peerlbl_active) {
4975 u32 if_sid;
4976 u32 node_sid;
4977
4978 if (sel_netif_sid(ifindex, &if_sid))
4979 return NF_DROP;
4980 if (avc_has_perm(peer_sid, if_sid,
4981 SECCLASS_NETIF, NETIF__EGRESS, &ad))
4982 return NF_DROP_ERR(-ECONNREFUSED);
4983
4984 if (sel_netnode_sid(addrp, family, &node_sid))
4985 return NF_DROP;
4986 if (avc_has_perm(peer_sid, node_sid,
4987 SECCLASS_NODE, NODE__SENDTO, &ad))
4988 return NF_DROP_ERR(-ECONNREFUSED);
4989 }
4990
4991 return NF_ACCEPT;
4992}
4993
4994static unsigned int selinux_ipv4_postroute(const struct nf_hook_ops *ops,
4995 struct sk_buff *skb,
4996 const struct net_device *in,
4997 const struct net_device *out,
4998 int (*okfn)(struct sk_buff *))
4999{
5000 return selinux_ip_postroute(skb, out->ifindex, PF_INET);
5001}
5002
5003#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
5004static unsigned int selinux_ipv6_postroute(const struct nf_hook_ops *ops,
5005 struct sk_buff *skb,
5006 const struct net_device *in,
5007 const struct net_device *out,
5008 int (*okfn)(struct sk_buff *))
5009{
5010 return selinux_ip_postroute(skb, out->ifindex, PF_INET6);
5011}
5012#endif /* IPV6 */
5013
5014#endif /* CONFIG_NETFILTER */
5015
5016static int selinux_netlink_send(struct sock *sk, struct sk_buff *skb)
5017{
5018 int err;
5019
5020 err = cap_netlink_send(sk, skb);
5021 if (err)
5022 return err;
5023
5024 return selinux_nlmsg_perm(sk, skb);
5025}
5026
5027static int ipc_alloc_security(struct task_struct *task,
5028 struct kern_ipc_perm *perm,
5029 u16 sclass)
5030{
5031 struct ipc_security_struct *isec;
5032 u32 sid;
5033
5034 isec = kzalloc(sizeof(struct ipc_security_struct), GFP_KERNEL);
5035 if (!isec)
5036 return -ENOMEM;
5037
5038 sid = task_sid(task);
5039 isec->sclass = sclass;
5040 isec->sid = sid;
5041 perm->security = isec;
5042
5043 return 0;
5044}
5045
5046static void ipc_free_security(struct kern_ipc_perm *perm)
5047{
5048 struct ipc_security_struct *isec = perm->security;
5049 perm->security = NULL;
5050 kfree(isec);
5051}
5052
5053static int msg_msg_alloc_security(struct msg_msg *msg)
5054{
5055 struct msg_security_struct *msec;
5056
5057 msec = kzalloc(sizeof(struct msg_security_struct), GFP_KERNEL);
5058 if (!msec)
5059 return -ENOMEM;
5060
5061 msec->sid = SECINITSID_UNLABELED;
5062 msg->security = msec;
5063
5064 return 0;
5065}
5066
5067static void msg_msg_free_security(struct msg_msg *msg)
5068{
5069 struct msg_security_struct *msec = msg->security;
5070
5071 msg->security = NULL;
5072 kfree(msec);
5073}
5074
5075static int ipc_has_perm(struct kern_ipc_perm *ipc_perms,
5076 u32 perms)
5077{
5078 struct ipc_security_struct *isec;
5079 struct common_audit_data ad;
5080 u32 sid = current_sid();
5081
5082 isec = ipc_perms->security;
5083
5084 ad.type = LSM_AUDIT_DATA_IPC;
5085 ad.u.ipc_id = ipc_perms->key;
5086
5087 return avc_has_perm(sid, isec->sid, isec->sclass, perms, &ad);
5088}
5089
5090static int selinux_msg_msg_alloc_security(struct msg_msg *msg)
5091{
5092 return msg_msg_alloc_security(msg);
5093}
5094
5095static void selinux_msg_msg_free_security(struct msg_msg *msg)
5096{
5097 msg_msg_free_security(msg);
5098}
5099
5100/* message queue security operations */
5101static int selinux_msg_queue_alloc_security(struct msg_queue *msq)
5102{
5103 struct ipc_security_struct *isec;
5104 struct common_audit_data ad;
5105 u32 sid = current_sid();
5106 int rc;
5107
5108 rc = ipc_alloc_security(current, &msq->q_perm, SECCLASS_MSGQ);
5109 if (rc)
5110 return rc;
5111
5112 isec = msq->q_perm.security;
5113
5114 ad.type = LSM_AUDIT_DATA_IPC;
5115 ad.u.ipc_id = msq->q_perm.key;
5116
5117 rc = avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
5118 MSGQ__CREATE, &ad);
5119 if (rc) {
5120 ipc_free_security(&msq->q_perm);
5121 return rc;
5122 }
5123 return 0;
5124}
5125
5126static void selinux_msg_queue_free_security(struct msg_queue *msq)
5127{
5128 ipc_free_security(&msq->q_perm);
5129}
5130
5131static int selinux_msg_queue_associate(struct msg_queue *msq, int msqflg)
5132{
5133 struct ipc_security_struct *isec;
5134 struct common_audit_data ad;
5135 u32 sid = current_sid();
5136
5137 isec = msq->q_perm.security;
5138
5139 ad.type = LSM_AUDIT_DATA_IPC;
5140 ad.u.ipc_id = msq->q_perm.key;
5141
5142 return avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
5143 MSGQ__ASSOCIATE, &ad);
5144}
5145
5146static int selinux_msg_queue_msgctl(struct msg_queue *msq, int cmd)
5147{
5148 int err;
5149 int perms;
5150
5151 switch (cmd) {
5152 case IPC_INFO:
5153 case MSG_INFO:
5154 /* No specific object, just general system-wide information. */
5155 return task_has_system(current, SYSTEM__IPC_INFO);
5156 case IPC_STAT:
5157 case MSG_STAT:
5158 perms = MSGQ__GETATTR | MSGQ__ASSOCIATE;
5159 break;
5160 case IPC_SET:
5161 perms = MSGQ__SETATTR;
5162 break;
5163 case IPC_RMID:
5164 perms = MSGQ__DESTROY;
5165 break;
5166 default:
5167 return 0;
5168 }
5169
5170 err = ipc_has_perm(&msq->q_perm, perms);
5171 return err;
5172}
5173
5174static int selinux_msg_queue_msgsnd(struct msg_queue *msq, struct msg_msg *msg, int msqflg)
5175{
5176 struct ipc_security_struct *isec;
5177 struct msg_security_struct *msec;
5178 struct common_audit_data ad;
5179 u32 sid = current_sid();
5180 int rc;
5181
5182 isec = msq->q_perm.security;
5183 msec = msg->security;
5184
5185 /*
5186 * First time through, need to assign label to the message
5187 */
5188 if (msec->sid == SECINITSID_UNLABELED) {
5189 /*
5190 * Compute new sid based on current process and
5191 * message queue this message will be stored in
5192 */
5193 rc = security_transition_sid(sid, isec->sid, SECCLASS_MSG,
5194 NULL, &msec->sid);
5195 if (rc)
5196 return rc;
5197 }
5198
5199 ad.type = LSM_AUDIT_DATA_IPC;
5200 ad.u.ipc_id = msq->q_perm.key;
5201
5202 /* Can this process write to the queue? */
5203 rc = avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
5204 MSGQ__WRITE, &ad);
5205 if (!rc)
5206 /* Can this process send the message */
5207 rc = avc_has_perm(sid, msec->sid, SECCLASS_MSG,
5208 MSG__SEND, &ad);
5209 if (!rc)
5210 /* Can the message be put in the queue? */
5211 rc = avc_has_perm(msec->sid, isec->sid, SECCLASS_MSGQ,
5212 MSGQ__ENQUEUE, &ad);
5213
5214 return rc;
5215}
5216
5217static int selinux_msg_queue_msgrcv(struct msg_queue *msq, struct msg_msg *msg,
5218 struct task_struct *target,
5219 long type, int mode)
5220{
5221 struct ipc_security_struct *isec;
5222 struct msg_security_struct *msec;
5223 struct common_audit_data ad;
5224 u32 sid = task_sid(target);
5225 int rc;
5226
5227 isec = msq->q_perm.security;
5228 msec = msg->security;
5229
5230 ad.type = LSM_AUDIT_DATA_IPC;
5231 ad.u.ipc_id = msq->q_perm.key;
5232
5233 rc = avc_has_perm(sid, isec->sid,
5234 SECCLASS_MSGQ, MSGQ__READ, &ad);
5235 if (!rc)
5236 rc = avc_has_perm(sid, msec->sid,
5237 SECCLASS_MSG, MSG__RECEIVE, &ad);
5238 return rc;
5239}
5240
5241/* Shared Memory security operations */
5242static int selinux_shm_alloc_security(struct shmid_kernel *shp)
5243{
5244 struct ipc_security_struct *isec;
5245 struct common_audit_data ad;
5246 u32 sid = current_sid();
5247 int rc;
5248
5249 rc = ipc_alloc_security(current, &shp->shm_perm, SECCLASS_SHM);
5250 if (rc)
5251 return rc;
5252
5253 isec = shp->shm_perm.security;
5254
5255 ad.type = LSM_AUDIT_DATA_IPC;
5256 ad.u.ipc_id = shp->shm_perm.key;
5257
5258 rc = avc_has_perm(sid, isec->sid, SECCLASS_SHM,
5259 SHM__CREATE, &ad);
5260 if (rc) {
5261 ipc_free_security(&shp->shm_perm);
5262 return rc;
5263 }
5264 return 0;
5265}
5266
5267static void selinux_shm_free_security(struct shmid_kernel *shp)
5268{
5269 ipc_free_security(&shp->shm_perm);
5270}
5271
5272static int selinux_shm_associate(struct shmid_kernel *shp, int shmflg)
5273{
5274 struct ipc_security_struct *isec;
5275 struct common_audit_data ad;
5276 u32 sid = current_sid();
5277
5278 isec = shp->shm_perm.security;
5279
5280 ad.type = LSM_AUDIT_DATA_IPC;
5281 ad.u.ipc_id = shp->shm_perm.key;
5282
5283 return avc_has_perm(sid, isec->sid, SECCLASS_SHM,
5284 SHM__ASSOCIATE, &ad);
5285}
5286
5287/* Note, at this point, shp is locked down */
5288static int selinux_shm_shmctl(struct shmid_kernel *shp, int cmd)
5289{
5290 int perms;
5291 int err;
5292
5293 switch (cmd) {
5294 case IPC_INFO:
5295 case SHM_INFO:
5296 /* No specific object, just general system-wide information. */
5297 return task_has_system(current, SYSTEM__IPC_INFO);
5298 case IPC_STAT:
5299 case SHM_STAT:
5300 perms = SHM__GETATTR | SHM__ASSOCIATE;
5301 break;
5302 case IPC_SET:
5303 perms = SHM__SETATTR;
5304 break;
5305 case SHM_LOCK:
5306 case SHM_UNLOCK:
5307 perms = SHM__LOCK;
5308 break;
5309 case IPC_RMID:
5310 perms = SHM__DESTROY;
5311 break;
5312 default:
5313 return 0;
5314 }
5315
5316 err = ipc_has_perm(&shp->shm_perm, perms);
5317 return err;
5318}
5319
5320static int selinux_shm_shmat(struct shmid_kernel *shp,
5321 char __user *shmaddr, int shmflg)
5322{
5323 u32 perms;
5324
5325 if (shmflg & SHM_RDONLY)
5326 perms = SHM__READ;
5327 else
5328 perms = SHM__READ | SHM__WRITE;
5329
5330 return ipc_has_perm(&shp->shm_perm, perms);
5331}
5332
5333/* Semaphore security operations */
5334static int selinux_sem_alloc_security(struct sem_array *sma)
5335{
5336 struct ipc_security_struct *isec;
5337 struct common_audit_data ad;
5338 u32 sid = current_sid();
5339 int rc;
5340
5341 rc = ipc_alloc_security(current, &sma->sem_perm, SECCLASS_SEM);
5342 if (rc)
5343 return rc;
5344
5345 isec = sma->sem_perm.security;
5346
5347 ad.type = LSM_AUDIT_DATA_IPC;
5348 ad.u.ipc_id = sma->sem_perm.key;
5349
5350 rc = avc_has_perm(sid, isec->sid, SECCLASS_SEM,
5351 SEM__CREATE, &ad);
5352 if (rc) {
5353 ipc_free_security(&sma->sem_perm);
5354 return rc;
5355 }
5356 return 0;
5357}
5358
5359static void selinux_sem_free_security(struct sem_array *sma)
5360{
5361 ipc_free_security(&sma->sem_perm);
5362}
5363
5364static int selinux_sem_associate(struct sem_array *sma, int semflg)
5365{
5366 struct ipc_security_struct *isec;
5367 struct common_audit_data ad;
5368 u32 sid = current_sid();
5369
5370 isec = sma->sem_perm.security;
5371
5372 ad.type = LSM_AUDIT_DATA_IPC;
5373 ad.u.ipc_id = sma->sem_perm.key;
5374
5375 return avc_has_perm(sid, isec->sid, SECCLASS_SEM,
5376 SEM__ASSOCIATE, &ad);
5377}
5378
5379/* Note, at this point, sma is locked down */
5380static int selinux_sem_semctl(struct sem_array *sma, int cmd)
5381{
5382 int err;
5383 u32 perms;
5384
5385 switch (cmd) {
5386 case IPC_INFO:
5387 case SEM_INFO:
5388 /* No specific object, just general system-wide information. */
5389 return task_has_system(current, SYSTEM__IPC_INFO);
5390 case GETPID:
5391 case GETNCNT:
5392 case GETZCNT:
5393 perms = SEM__GETATTR;
5394 break;
5395 case GETVAL:
5396 case GETALL:
5397 perms = SEM__READ;
5398 break;
5399 case SETVAL:
5400 case SETALL:
5401 perms = SEM__WRITE;
5402 break;
5403 case IPC_RMID:
5404 perms = SEM__DESTROY;
5405 break;
5406 case IPC_SET:
5407 perms = SEM__SETATTR;
5408 break;
5409 case IPC_STAT:
5410 case SEM_STAT:
5411 perms = SEM__GETATTR | SEM__ASSOCIATE;
5412 break;
5413 default:
5414 return 0;
5415 }
5416
5417 err = ipc_has_perm(&sma->sem_perm, perms);
5418 return err;
5419}
5420
5421static int selinux_sem_semop(struct sem_array *sma,
5422 struct sembuf *sops, unsigned nsops, int alter)
5423{
5424 u32 perms;
5425
5426 if (alter)
5427 perms = SEM__READ | SEM__WRITE;
5428 else
5429 perms = SEM__READ;
5430
5431 return ipc_has_perm(&sma->sem_perm, perms);
5432}
5433
5434static int selinux_ipc_permission(struct kern_ipc_perm *ipcp, short flag)
5435{
5436 u32 av = 0;
5437
5438 av = 0;
5439 if (flag & S_IRUGO)
5440 av |= IPC__UNIX_READ;
5441 if (flag & S_IWUGO)
5442 av |= IPC__UNIX_WRITE;
5443
5444 if (av == 0)
5445 return 0;
5446
5447 return ipc_has_perm(ipcp, av);
5448}
5449
5450static void selinux_ipc_getsecid(struct kern_ipc_perm *ipcp, u32 *secid)
5451{
5452 struct ipc_security_struct *isec = ipcp->security;
5453 *secid = isec->sid;
5454}
5455
5456static void selinux_d_instantiate(struct dentry *dentry, struct inode *inode)
5457{
5458 if (inode)
5459 inode_doinit_with_dentry(inode, dentry);
5460}
5461
5462static int selinux_getprocattr(struct task_struct *p,
5463 char *name, char **value)
5464{
5465 const struct task_security_struct *__tsec;
5466 u32 sid;
5467 int error;
5468 unsigned len;
5469
5470 if (current != p) {
5471 error = current_has_perm(p, PROCESS__GETATTR);
5472 if (error)
5473 return error;
5474 }
5475
5476 rcu_read_lock();
5477 __tsec = __task_cred(p)->security;
5478
5479 if (!strcmp(name, "current"))
5480 sid = __tsec->sid;
5481 else if (!strcmp(name, "prev"))
5482 sid = __tsec->osid;
5483 else if (!strcmp(name, "exec"))
5484 sid = __tsec->exec_sid;
5485 else if (!strcmp(name, "fscreate"))
5486 sid = __tsec->create_sid;
5487 else if (!strcmp(name, "keycreate"))
5488 sid = __tsec->keycreate_sid;
5489 else if (!strcmp(name, "sockcreate"))
5490 sid = __tsec->sockcreate_sid;
5491 else
5492 goto invalid;
5493 rcu_read_unlock();
5494
5495 if (!sid)
5496 return 0;
5497
5498 error = security_sid_to_context(sid, value, &len);
5499 if (error)
5500 return error;
5501 return len;
5502
5503invalid:
5504 rcu_read_unlock();
5505 return -EINVAL;
5506}
5507
5508static int selinux_setprocattr(struct task_struct *p,
5509 char *name, void *value, size_t size)
5510{
5511 struct task_security_struct *tsec;
5512 struct task_struct *tracer;
5513 struct cred *new;
5514 u32 sid = 0, ptsid;
5515 int error;
5516 char *str = value;
5517
5518 if (current != p) {
5519 /* SELinux only allows a process to change its own
5520 security attributes. */
5521 return -EACCES;
5522 }
5523
5524 /*
5525 * Basic control over ability to set these attributes at all.
5526 * current == p, but we'll pass them separately in case the
5527 * above restriction is ever removed.
5528 */
5529 if (!strcmp(name, "exec"))
5530 error = current_has_perm(p, PROCESS__SETEXEC);
5531 else if (!strcmp(name, "fscreate"))
5532 error = current_has_perm(p, PROCESS__SETFSCREATE);
5533 else if (!strcmp(name, "keycreate"))
5534 error = current_has_perm(p, PROCESS__SETKEYCREATE);
5535 else if (!strcmp(name, "sockcreate"))
5536 error = current_has_perm(p, PROCESS__SETSOCKCREATE);
5537 else if (!strcmp(name, "current"))
5538 error = current_has_perm(p, PROCESS__SETCURRENT);
5539 else
5540 error = -EINVAL;
5541 if (error)
5542 return error;
5543
5544 /* Obtain a SID for the context, if one was specified. */
5545 if (size && str[1] && str[1] != '\n') {
5546 if (str[size-1] == '\n') {
5547 str[size-1] = 0;
5548 size--;
5549 }
5550 error = security_context_to_sid(value, size, &sid, GFP_KERNEL);
5551 if (error == -EINVAL && !strcmp(name, "fscreate")) {
5552 if (!capable(CAP_MAC_ADMIN)) {
5553 struct audit_buffer *ab;
5554 size_t audit_size;
5555
5556 /* We strip a nul only if it is at the end, otherwise the
5557 * context contains a nul and we should audit that */
5558 if (str[size - 1] == '\0')
5559 audit_size = size - 1;
5560 else
5561 audit_size = size;
5562 ab = audit_log_start(current->audit_context, GFP_ATOMIC, AUDIT_SELINUX_ERR);
5563 audit_log_format(ab, "op=fscreate invalid_context=");
5564 audit_log_n_untrustedstring(ab, value, audit_size);
5565 audit_log_end(ab);
5566
5567 return error;
5568 }
5569 error = security_context_to_sid_force(value, size,
5570 &sid);
5571 }
5572 if (error)
5573 return error;
5574 }
5575
5576 new = prepare_creds();
5577 if (!new)
5578 return -ENOMEM;
5579
5580 /* Permission checking based on the specified context is
5581 performed during the actual operation (execve,
5582 open/mkdir/...), when we know the full context of the
5583 operation. See selinux_bprm_set_creds for the execve
5584 checks and may_create for the file creation checks. The
5585 operation will then fail if the context is not permitted. */
5586 tsec = new->security;
5587 if (!strcmp(name, "exec")) {
5588 tsec->exec_sid = sid;
5589 } else if (!strcmp(name, "fscreate")) {
5590 tsec->create_sid = sid;
5591 } else if (!strcmp(name, "keycreate")) {
5592 error = may_create_key(sid, p);
5593 if (error)
5594 goto abort_change;
5595 tsec->keycreate_sid = sid;
5596 } else if (!strcmp(name, "sockcreate")) {
5597 tsec->sockcreate_sid = sid;
5598 } else if (!strcmp(name, "current")) {
5599 error = -EINVAL;
5600 if (sid == 0)
5601 goto abort_change;
5602
5603 /* Only allow single threaded processes to change context */
5604 error = -EPERM;
5605 if (!current_is_single_threaded()) {
5606 error = security_bounded_transition(tsec->sid, sid);
5607 if (error)
5608 goto abort_change;
5609 }
5610
5611 /* Check permissions for the transition. */
5612 error = avc_has_perm(tsec->sid, sid, SECCLASS_PROCESS,
5613 PROCESS__DYNTRANSITION, NULL);
5614 if (error)
5615 goto abort_change;
5616
5617 /* Check for ptracing, and update the task SID if ok.
5618 Otherwise, leave SID unchanged and fail. */
5619 ptsid = 0;
5620 rcu_read_lock();
5621 tracer = ptrace_parent(p);
5622 if (tracer)
5623 ptsid = task_sid(tracer);
5624 rcu_read_unlock();
5625
5626 if (tracer) {
5627 error = avc_has_perm(ptsid, sid, SECCLASS_PROCESS,
5628 PROCESS__PTRACE, NULL);
5629 if (error)
5630 goto abort_change;
5631 }
5632
5633 tsec->sid = sid;
5634 } else {
5635 error = -EINVAL;
5636 goto abort_change;
5637 }
5638
5639 commit_creds(new);
5640 return size;
5641
5642abort_change:
5643 abort_creds(new);
5644 return error;
5645}
5646
5647static int selinux_ismaclabel(const char *name)
5648{
5649 return (strcmp(name, XATTR_SELINUX_SUFFIX) == 0);
5650}
5651
5652static int selinux_secid_to_secctx(u32 secid, char **secdata, u32 *seclen)
5653{
5654 return security_sid_to_context(secid, secdata, seclen);
5655}
5656
5657static int selinux_secctx_to_secid(const char *secdata, u32 seclen, u32 *secid)
5658{
5659 return security_context_to_sid(secdata, seclen, secid, GFP_KERNEL);
5660}
5661
5662static void selinux_release_secctx(char *secdata, u32 seclen)
5663{
5664 kfree(secdata);
5665}
5666
5667/*
5668 * called with inode->i_mutex locked
5669 */
5670static int selinux_inode_notifysecctx(struct inode *inode, void *ctx, u32 ctxlen)
5671{
5672 return selinux_inode_setsecurity(inode, XATTR_SELINUX_SUFFIX, ctx, ctxlen, 0);
5673}
5674
5675/*
5676 * called with inode->i_mutex locked
5677 */
5678static int selinux_inode_setsecctx(struct dentry *dentry, void *ctx, u32 ctxlen)
5679{
5680 return __vfs_setxattr_noperm(dentry, XATTR_NAME_SELINUX, ctx, ctxlen, 0);
5681}
5682
5683static int selinux_inode_getsecctx(struct inode *inode, void **ctx, u32 *ctxlen)
5684{
5685 int len = 0;
5686 len = selinux_inode_getsecurity(inode, XATTR_SELINUX_SUFFIX,
5687 ctx, true);
5688 if (len < 0)
5689 return len;
5690 *ctxlen = len;
5691 return 0;
5692}
5693#ifdef CONFIG_KEYS
5694
5695static int selinux_key_alloc(struct key *k, const struct cred *cred,
5696 unsigned long flags)
5697{
5698 const struct task_security_struct *tsec;
5699 struct key_security_struct *ksec;
5700
5701 ksec = kzalloc(sizeof(struct key_security_struct), GFP_KERNEL);
5702 if (!ksec)
5703 return -ENOMEM;
5704
5705 tsec = cred->security;
5706 if (tsec->keycreate_sid)
5707 ksec->sid = tsec->keycreate_sid;
5708 else
5709 ksec->sid = tsec->sid;
5710
5711 k->security = ksec;
5712 return 0;
5713}
5714
5715static void selinux_key_free(struct key *k)
5716{
5717 struct key_security_struct *ksec = k->security;
5718
5719 k->security = NULL;
5720 kfree(ksec);
5721}
5722
5723static int selinux_key_permission(key_ref_t key_ref,
5724 const struct cred *cred,
5725 key_perm_t perm)
5726{
5727 struct key *key;
5728 struct key_security_struct *ksec;
5729 u32 sid;
5730
5731 /* if no specific permissions are requested, we skip the
5732 permission check. No serious, additional covert channels
5733 appear to be created. */
5734 if (perm == 0)
5735 return 0;
5736
5737 sid = cred_sid(cred);
5738
5739 key = key_ref_to_ptr(key_ref);
5740 ksec = key->security;
5741
5742 return avc_has_perm(sid, ksec->sid, SECCLASS_KEY, perm, NULL);
5743}
5744
5745static int selinux_key_getsecurity(struct key *key, char **_buffer)
5746{
5747 struct key_security_struct *ksec = key->security;
5748 char *context = NULL;
5749 unsigned len;
5750 int rc;
5751
5752 rc = security_sid_to_context(ksec->sid, &context, &len);
5753 if (!rc)
5754 rc = len;
5755 *_buffer = context;
5756 return rc;
5757}
5758
5759#endif
5760
5761static struct security_operations selinux_ops = {
5762 .name = "selinux",
5763
5764 .ptrace_access_check = selinux_ptrace_access_check,
5765 .ptrace_traceme = selinux_ptrace_traceme,
5766 .capget = selinux_capget,
5767 .capset = selinux_capset,
5768 .capable = selinux_capable,
5769 .quotactl = selinux_quotactl,
5770 .quota_on = selinux_quota_on,
5771 .syslog = selinux_syslog,
5772 .vm_enough_memory = selinux_vm_enough_memory,
5773
5774 .netlink_send = selinux_netlink_send,
5775
5776 .bprm_set_creds = selinux_bprm_set_creds,
5777 .bprm_committing_creds = selinux_bprm_committing_creds,
5778 .bprm_committed_creds = selinux_bprm_committed_creds,
5779 .bprm_secureexec = selinux_bprm_secureexec,
5780
5781 .sb_alloc_security = selinux_sb_alloc_security,
5782 .sb_free_security = selinux_sb_free_security,
5783 .sb_copy_data = selinux_sb_copy_data,
5784 .sb_remount = selinux_sb_remount,
5785 .sb_kern_mount = selinux_sb_kern_mount,
5786 .sb_show_options = selinux_sb_show_options,
5787 .sb_statfs = selinux_sb_statfs,
5788 .sb_mount = selinux_mount,
5789 .sb_umount = selinux_umount,
5790 .sb_set_mnt_opts = selinux_set_mnt_opts,
5791 .sb_clone_mnt_opts = selinux_sb_clone_mnt_opts,
5792 .sb_parse_opts_str = selinux_parse_opts_str,
5793
5794 .dentry_init_security = selinux_dentry_init_security,
5795
5796 .inode_alloc_security = selinux_inode_alloc_security,
5797 .inode_free_security = selinux_inode_free_security,
5798 .inode_init_security = selinux_inode_init_security,
5799 .inode_create = selinux_inode_create,
5800 .inode_link = selinux_inode_link,
5801 .inode_unlink = selinux_inode_unlink,
5802 .inode_symlink = selinux_inode_symlink,
5803 .inode_mkdir = selinux_inode_mkdir,
5804 .inode_rmdir = selinux_inode_rmdir,
5805 .inode_mknod = selinux_inode_mknod,
5806 .inode_rename = selinux_inode_rename,
5807 .inode_readlink = selinux_inode_readlink,
5808 .inode_follow_link = selinux_inode_follow_link,
5809 .inode_permission = selinux_inode_permission,
5810 .inode_setattr = selinux_inode_setattr,
5811 .inode_getattr = selinux_inode_getattr,
5812 .inode_setxattr = selinux_inode_setxattr,
5813 .inode_post_setxattr = selinux_inode_post_setxattr,
5814 .inode_getxattr = selinux_inode_getxattr,
5815 .inode_listxattr = selinux_inode_listxattr,
5816 .inode_removexattr = selinux_inode_removexattr,
5817 .inode_getsecurity = selinux_inode_getsecurity,
5818 .inode_setsecurity = selinux_inode_setsecurity,
5819 .inode_listsecurity = selinux_inode_listsecurity,
5820 .inode_getsecid = selinux_inode_getsecid,
5821
5822 .file_permission = selinux_file_permission,
5823 .file_alloc_security = selinux_file_alloc_security,
5824 .file_free_security = selinux_file_free_security,
5825 .file_ioctl = selinux_file_ioctl,
5826 .mmap_file = selinux_mmap_file,
5827 .mmap_addr = selinux_mmap_addr,
5828 .file_mprotect = selinux_file_mprotect,
5829 .file_lock = selinux_file_lock,
5830 .file_fcntl = selinux_file_fcntl,
5831 .file_set_fowner = selinux_file_set_fowner,
5832 .file_send_sigiotask = selinux_file_send_sigiotask,
5833 .file_receive = selinux_file_receive,
5834
5835 .file_open = selinux_file_open,
5836
5837 .task_create = selinux_task_create,
5838 .cred_alloc_blank = selinux_cred_alloc_blank,
5839 .cred_free = selinux_cred_free,
5840 .cred_prepare = selinux_cred_prepare,
5841 .cred_transfer = selinux_cred_transfer,
5842 .kernel_act_as = selinux_kernel_act_as,
5843 .kernel_create_files_as = selinux_kernel_create_files_as,
5844 .kernel_module_request = selinux_kernel_module_request,
5845 .task_setpgid = selinux_task_setpgid,
5846 .task_getpgid = selinux_task_getpgid,
5847 .task_getsid = selinux_task_getsid,
5848 .task_getsecid = selinux_task_getsecid,
5849 .task_setnice = selinux_task_setnice,
5850 .task_setioprio = selinux_task_setioprio,
5851 .task_getioprio = selinux_task_getioprio,
5852 .task_setrlimit = selinux_task_setrlimit,
5853 .task_setscheduler = selinux_task_setscheduler,
5854 .task_getscheduler = selinux_task_getscheduler,
5855 .task_movememory = selinux_task_movememory,
5856 .task_kill = selinux_task_kill,
5857 .task_wait = selinux_task_wait,
5858 .task_to_inode = selinux_task_to_inode,
5859
5860 .ipc_permission = selinux_ipc_permission,
5861 .ipc_getsecid = selinux_ipc_getsecid,
5862
5863 .msg_msg_alloc_security = selinux_msg_msg_alloc_security,
5864 .msg_msg_free_security = selinux_msg_msg_free_security,
5865
5866 .msg_queue_alloc_security = selinux_msg_queue_alloc_security,
5867 .msg_queue_free_security = selinux_msg_queue_free_security,
5868 .msg_queue_associate = selinux_msg_queue_associate,
5869 .msg_queue_msgctl = selinux_msg_queue_msgctl,
5870 .msg_queue_msgsnd = selinux_msg_queue_msgsnd,
5871 .msg_queue_msgrcv = selinux_msg_queue_msgrcv,
5872
5873 .shm_alloc_security = selinux_shm_alloc_security,
5874 .shm_free_security = selinux_shm_free_security,
5875 .shm_associate = selinux_shm_associate,
5876 .shm_shmctl = selinux_shm_shmctl,
5877 .shm_shmat = selinux_shm_shmat,
5878
5879 .sem_alloc_security = selinux_sem_alloc_security,
5880 .sem_free_security = selinux_sem_free_security,
5881 .sem_associate = selinux_sem_associate,
5882 .sem_semctl = selinux_sem_semctl,
5883 .sem_semop = selinux_sem_semop,
5884
5885 .d_instantiate = selinux_d_instantiate,
5886
5887 .getprocattr = selinux_getprocattr,
5888 .setprocattr = selinux_setprocattr,
5889
5890 .ismaclabel = selinux_ismaclabel,
5891 .secid_to_secctx = selinux_secid_to_secctx,
5892 .secctx_to_secid = selinux_secctx_to_secid,
5893 .release_secctx = selinux_release_secctx,
5894 .inode_notifysecctx = selinux_inode_notifysecctx,
5895 .inode_setsecctx = selinux_inode_setsecctx,
5896 .inode_getsecctx = selinux_inode_getsecctx,
5897
5898 .unix_stream_connect = selinux_socket_unix_stream_connect,
5899 .unix_may_send = selinux_socket_unix_may_send,
5900
5901 .socket_create = selinux_socket_create,
5902 .socket_post_create = selinux_socket_post_create,
5903 .socket_bind = selinux_socket_bind,
5904 .socket_connect = selinux_socket_connect,
5905 .socket_listen = selinux_socket_listen,
5906 .socket_accept = selinux_socket_accept,
5907 .socket_sendmsg = selinux_socket_sendmsg,
5908 .socket_recvmsg = selinux_socket_recvmsg,
5909 .socket_getsockname = selinux_socket_getsockname,
5910 .socket_getpeername = selinux_socket_getpeername,
5911 .socket_getsockopt = selinux_socket_getsockopt,
5912 .socket_setsockopt = selinux_socket_setsockopt,
5913 .socket_shutdown = selinux_socket_shutdown,
5914 .socket_sock_rcv_skb = selinux_socket_sock_rcv_skb,
5915 .socket_getpeersec_stream = selinux_socket_getpeersec_stream,
5916 .socket_getpeersec_dgram = selinux_socket_getpeersec_dgram,
5917 .sk_alloc_security = selinux_sk_alloc_security,
5918 .sk_free_security = selinux_sk_free_security,
5919 .sk_clone_security = selinux_sk_clone_security,
5920 .sk_getsecid = selinux_sk_getsecid,
5921 .sock_graft = selinux_sock_graft,
5922 .inet_conn_request = selinux_inet_conn_request,
5923 .inet_csk_clone = selinux_inet_csk_clone,
5924 .inet_conn_established = selinux_inet_conn_established,
5925 .secmark_relabel_packet = selinux_secmark_relabel_packet,
5926 .secmark_refcount_inc = selinux_secmark_refcount_inc,
5927 .secmark_refcount_dec = selinux_secmark_refcount_dec,
5928 .req_classify_flow = selinux_req_classify_flow,
5929 .tun_dev_alloc_security = selinux_tun_dev_alloc_security,
5930 .tun_dev_free_security = selinux_tun_dev_free_security,
5931 .tun_dev_create = selinux_tun_dev_create,
5932 .tun_dev_attach_queue = selinux_tun_dev_attach_queue,
5933 .tun_dev_attach = selinux_tun_dev_attach,
5934 .tun_dev_open = selinux_tun_dev_open,
5935 .skb_owned_by = selinux_skb_owned_by,
5936
5937#ifdef CONFIG_SECURITY_NETWORK_XFRM
5938 .xfrm_policy_alloc_security = selinux_xfrm_policy_alloc,
5939 .xfrm_policy_clone_security = selinux_xfrm_policy_clone,
5940 .xfrm_policy_free_security = selinux_xfrm_policy_free,
5941 .xfrm_policy_delete_security = selinux_xfrm_policy_delete,
5942 .xfrm_state_alloc = selinux_xfrm_state_alloc,
5943 .xfrm_state_alloc_acquire = selinux_xfrm_state_alloc_acquire,
5944 .xfrm_state_free_security = selinux_xfrm_state_free,
5945 .xfrm_state_delete_security = selinux_xfrm_state_delete,
5946 .xfrm_policy_lookup = selinux_xfrm_policy_lookup,
5947 .xfrm_state_pol_flow_match = selinux_xfrm_state_pol_flow_match,
5948 .xfrm_decode_session = selinux_xfrm_decode_session,
5949#endif
5950
5951#ifdef CONFIG_KEYS
5952 .key_alloc = selinux_key_alloc,
5953 .key_free = selinux_key_free,
5954 .key_permission = selinux_key_permission,
5955 .key_getsecurity = selinux_key_getsecurity,
5956#endif
5957
5958#ifdef CONFIG_AUDIT
5959 .audit_rule_init = selinux_audit_rule_init,
5960 .audit_rule_known = selinux_audit_rule_known,
5961 .audit_rule_match = selinux_audit_rule_match,
5962 .audit_rule_free = selinux_audit_rule_free,
5963#endif
5964};
5965
5966static __init int selinux_init(void)
5967{
5968 if (!security_module_enable(&selinux_ops)) {
5969 selinux_enabled = 0;
5970 return 0;
5971 }
5972
5973 if (!selinux_enabled) {
5974 printk(KERN_INFO "SELinux: Disabled at boot.\n");
5975 return 0;
5976 }
5977
5978 printk(KERN_INFO "SELinux: Initializing.\n");
5979
5980 /* Set the security state for the initial task. */
5981 cred_init_security();
5982
5983 default_noexec = !(VM_DATA_DEFAULT_FLAGS & VM_EXEC);
5984
5985 sel_inode_cache = kmem_cache_create("selinux_inode_security",
5986 sizeof(struct inode_security_struct),
5987 0, SLAB_PANIC, NULL);
5988 avc_init();
5989
5990 if (register_security(&selinux_ops))
5991 panic("SELinux: Unable to register with kernel.\n");
5992
5993 if (selinux_enforcing)
5994 printk(KERN_DEBUG "SELinux: Starting in enforcing mode\n");
5995 else
5996 printk(KERN_DEBUG "SELinux: Starting in permissive mode\n");
5997
5998 return 0;
5999}
6000
6001static void delayed_superblock_init(struct super_block *sb, void *unused)
6002{
6003 superblock_doinit(sb, NULL);
6004}
6005
6006void selinux_complete_init(void)
6007{
6008 printk(KERN_DEBUG "SELinux: Completing initialization.\n");
6009
6010 /* Set up any superblocks initialized prior to the policy load. */
6011 printk(KERN_DEBUG "SELinux: Setting up existing superblocks.\n");
6012 iterate_supers(delayed_superblock_init, NULL);
6013}
6014
6015/* SELinux requires early initialization in order to label
6016 all processes and objects when they are created. */
6017security_initcall(selinux_init);
6018
6019#if defined(CONFIG_NETFILTER)
6020
6021static struct nf_hook_ops selinux_ipv4_ops[] = {
6022 {
6023 .hook = selinux_ipv4_postroute,
6024 .owner = THIS_MODULE,
6025 .pf = NFPROTO_IPV4,
6026 .hooknum = NF_INET_POST_ROUTING,
6027 .priority = NF_IP_PRI_SELINUX_LAST,
6028 },
6029 {
6030 .hook = selinux_ipv4_forward,
6031 .owner = THIS_MODULE,
6032 .pf = NFPROTO_IPV4,
6033 .hooknum = NF_INET_FORWARD,
6034 .priority = NF_IP_PRI_SELINUX_FIRST,
6035 },
6036 {
6037 .hook = selinux_ipv4_output,
6038 .owner = THIS_MODULE,
6039 .pf = NFPROTO_IPV4,
6040 .hooknum = NF_INET_LOCAL_OUT,
6041 .priority = NF_IP_PRI_SELINUX_FIRST,
6042 }
6043};
6044
6045#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
6046
6047static struct nf_hook_ops selinux_ipv6_ops[] = {
6048 {
6049 .hook = selinux_ipv6_postroute,
6050 .owner = THIS_MODULE,
6051 .pf = NFPROTO_IPV6,
6052 .hooknum = NF_INET_POST_ROUTING,
6053 .priority = NF_IP6_PRI_SELINUX_LAST,
6054 },
6055 {
6056 .hook = selinux_ipv6_forward,
6057 .owner = THIS_MODULE,
6058 .pf = NFPROTO_IPV6,
6059 .hooknum = NF_INET_FORWARD,
6060 .priority = NF_IP6_PRI_SELINUX_FIRST,
6061 }
6062};
6063
6064#endif /* IPV6 */
6065
6066static int __init selinux_nf_ip_init(void)
6067{
6068 int err = 0;
6069
6070 if (!selinux_enabled)
6071 goto out;
6072
6073 printk(KERN_DEBUG "SELinux: Registering netfilter hooks\n");
6074
6075 err = nf_register_hooks(selinux_ipv4_ops, ARRAY_SIZE(selinux_ipv4_ops));
6076 if (err)
6077 panic("SELinux: nf_register_hooks for IPv4: error %d\n", err);
6078
6079#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
6080 err = nf_register_hooks(selinux_ipv6_ops, ARRAY_SIZE(selinux_ipv6_ops));
6081 if (err)
6082 panic("SELinux: nf_register_hooks for IPv6: error %d\n", err);
6083#endif /* IPV6 */
6084
6085out:
6086 return err;
6087}
6088
6089__initcall(selinux_nf_ip_init);
6090
6091#ifdef CONFIG_SECURITY_SELINUX_DISABLE
6092static void selinux_nf_ip_exit(void)
6093{
6094 printk(KERN_DEBUG "SELinux: Unregistering netfilter hooks\n");
6095
6096 nf_unregister_hooks(selinux_ipv4_ops, ARRAY_SIZE(selinux_ipv4_ops));
6097#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
6098 nf_unregister_hooks(selinux_ipv6_ops, ARRAY_SIZE(selinux_ipv6_ops));
6099#endif /* IPV6 */
6100}
6101#endif
6102
6103#else /* CONFIG_NETFILTER */
6104
6105#ifdef CONFIG_SECURITY_SELINUX_DISABLE
6106#define selinux_nf_ip_exit()
6107#endif
6108
6109#endif /* CONFIG_NETFILTER */
6110
6111#ifdef CONFIG_SECURITY_SELINUX_DISABLE
6112static int selinux_disabled;
6113
6114int selinux_disable(void)
6115{
6116 if (ss_initialized) {
6117 /* Not permitted after initial policy load. */
6118 return -EINVAL;
6119 }
6120
6121 if (selinux_disabled) {
6122 /* Only do this once. */
6123 return -EINVAL;
6124 }
6125
6126 printk(KERN_INFO "SELinux: Disabled at runtime.\n");
6127
6128 selinux_disabled = 1;
6129 selinux_enabled = 0;
6130
6131 reset_security_ops();
6132
6133 /* Try to destroy the avc node cache */
6134 avc_disable();
6135
6136 /* Unregister netfilter hooks. */
6137 selinux_nf_ip_exit();
6138
6139 /* Unregister selinuxfs. */
6140 exit_sel_fs();
6141
6142 return 0;
6143}
6144#endif