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vmcore: calculate vmcore file size from buffer size and total size of vmcore objects
[linux-2.6.git] / security / selinux / hooks.c
blobdb1fca990a2468a4ac292f50daba582df4dc113e
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/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 #define NUM_SEL_MNT_OPTS 5
98
99 extern struct security_operations *security_ops;
100
101 /* SECMARK reference count */
102 static atomic_t selinux_secmark_refcount = ATOMIC_INIT(0);
103
104 #ifdef CONFIG_SECURITY_SELINUX_DEVELOP
105 int selinux_enforcing;
106
107 static int __init enforcing_setup(char *str)
108 {
109 unsigned long enforcing;
110 if (!strict_strtoul(str, 0, &enforcing))
111 selinux_enforcing = enforcing ? 1 : 0;
112 return 1;
113 }
114 __setup("enforcing=", enforcing_setup);
115 #endif
116
117 #ifdef CONFIG_SECURITY_SELINUX_BOOTPARAM
118 int selinux_enabled = CONFIG_SECURITY_SELINUX_BOOTPARAM_VALUE;
119
120 static int __init selinux_enabled_setup(char *str)
121 {
122 unsigned long enabled;
123 if (!strict_strtoul(str, 0, &enabled))
124 selinux_enabled = enabled ? 1 : 0;
125 return 1;
126 }
127 __setup("selinux=", selinux_enabled_setup);
128 #else
129 int selinux_enabled = 1;
130 #endif
131
132 static struct kmem_cache *sel_inode_cache;
133
134 /**
135 * selinux_secmark_enabled - Check to see if SECMARK is currently enabled
136 *
137 * Description:
138 * This function checks the SECMARK reference counter to see if any SECMARK
139 * targets are currently configured, if the reference counter is greater than
140 * zero SECMARK is considered to be enabled. Returns true (1) if SECMARK is
141 * enabled, false (0) if SECMARK is disabled.
142 *
143 */
144 static int selinux_secmark_enabled(void)
145 {
146 return (atomic_read(&selinux_secmark_refcount) > 0);
147 }
148
149 /*
150 * initialise the security for the init task
151 */
152 static void cred_init_security(void)
153 {
154 struct cred *cred = (struct cred *) current->real_cred;
155 struct task_security_struct *tsec;
156
157 tsec = kzalloc(sizeof(struct task_security_struct), GFP_KERNEL);
158 if (!tsec)
159 panic("SELinux: Failed to initialize initial task.\n");
160
161 tsec->osid = tsec->sid = SECINITSID_KERNEL;
162 cred->security = tsec;
163 }
164
165 /*
166 * get the security ID of a set of credentials
167 */
168 static inline u32 cred_sid(const struct cred *cred)
169 {
170 const struct task_security_struct *tsec;
171
172 tsec = cred->security;
173 return tsec->sid;
174 }
175
176 /*
177 * get the objective security ID of a task
178 */
179 static inline u32 task_sid(const struct task_struct *task)
180 {
181 u32 sid;
182
183 rcu_read_lock();
184 sid = cred_sid(__task_cred(task));
185 rcu_read_unlock();
186 return sid;
187 }
188
189 /*
190 * get the subjective security ID of the current task
191 */
192 static inline u32 current_sid(void)
193 {
194 const struct task_security_struct *tsec = current_security();
195
196 return tsec->sid;
197 }
198
199 /* Allocate and free functions for each kind of security blob. */
200
201 static int inode_alloc_security(struct inode *inode)
202 {
203 struct inode_security_struct *isec;
204 u32 sid = current_sid();
205
206 isec = kmem_cache_zalloc(sel_inode_cache, GFP_NOFS);
207 if (!isec)
208 return -ENOMEM;
209
210 mutex_init(&isec->lock);
211 INIT_LIST_HEAD(&isec->list);
212 isec->inode = inode;
213 isec->sid = SECINITSID_UNLABELED;
214 isec->sclass = SECCLASS_FILE;
215 isec->task_sid = sid;
216 inode->i_security = isec;
217
218 return 0;
219 }
220
221 static void inode_free_security(struct inode *inode)
222 {
223 struct inode_security_struct *isec = inode->i_security;
224 struct superblock_security_struct *sbsec = inode->i_sb->s_security;
225
226 spin_lock(&sbsec->isec_lock);
227 if (!list_empty(&isec->list))
228 list_del_init(&isec->list);
229 spin_unlock(&sbsec->isec_lock);
230
231 inode->i_security = NULL;
232 kmem_cache_free(sel_inode_cache, isec);
233 }
234
235 static int file_alloc_security(struct file *file)
236 {
237 struct file_security_struct *fsec;
238 u32 sid = current_sid();
239
240 fsec = kzalloc(sizeof(struct file_security_struct), GFP_KERNEL);
241 if (!fsec)
242 return -ENOMEM;
243
244 fsec->sid = sid;
245 fsec->fown_sid = sid;
246 file->f_security = fsec;
247
248 return 0;
249 }
250
251 static void file_free_security(struct file *file)
252 {
253 struct file_security_struct *fsec = file->f_security;
254 file->f_security = NULL;
255 kfree(fsec);
256 }
257
258 static int superblock_alloc_security(struct super_block *sb)
259 {
260 struct superblock_security_struct *sbsec;
261
262 sbsec = kzalloc(sizeof(struct superblock_security_struct), GFP_KERNEL);
263 if (!sbsec)
264 return -ENOMEM;
265
266 mutex_init(&sbsec->lock);
267 INIT_LIST_HEAD(&sbsec->isec_head);
268 spin_lock_init(&sbsec->isec_lock);
269 sbsec->sb = sb;
270 sbsec->sid = SECINITSID_UNLABELED;
271 sbsec->def_sid = SECINITSID_FILE;
272 sbsec->mntpoint_sid = SECINITSID_UNLABELED;
273 sb->s_security = sbsec;
274
275 return 0;
276 }
277
278 static void superblock_free_security(struct super_block *sb)
279 {
280 struct superblock_security_struct *sbsec = sb->s_security;
281 sb->s_security = NULL;
282 kfree(sbsec);
283 }
284
285 /* The file system's label must be initialized prior to use. */
286
287 static const char *labeling_behaviors[6] = {
288 "uses xattr",
289 "uses transition SIDs",
290 "uses task SIDs",
291 "uses genfs_contexts",
292 "not configured for labeling",
293 "uses mountpoint labeling",
294 };
295
296 static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dentry);
297
298 static inline int inode_doinit(struct inode *inode)
299 {
300 return inode_doinit_with_dentry(inode, NULL);
301 }
302
303 enum {
304 Opt_error = -1,
305 Opt_context = 1,
306 Opt_fscontext = 2,
307 Opt_defcontext = 3,
308 Opt_rootcontext = 4,
309 Opt_labelsupport = 5,
310 };
311
312 static const match_table_t tokens = {
313 {Opt_context, CONTEXT_STR "%s"},
314 {Opt_fscontext, FSCONTEXT_STR "%s"},
315 {Opt_defcontext, DEFCONTEXT_STR "%s"},
316 {Opt_rootcontext, ROOTCONTEXT_STR "%s"},
317 {Opt_labelsupport, LABELSUPP_STR},
318 {Opt_error, NULL},
319 };
320
321 #define SEL_MOUNT_FAIL_MSG "SELinux: duplicate or incompatible mount options\n"
322
323 static int may_context_mount_sb_relabel(u32 sid,
324 struct superblock_security_struct *sbsec,
325 const struct cred *cred)
326 {
327 const struct task_security_struct *tsec = cred->security;
328 int rc;
329
330 rc = avc_has_perm(tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM,
331 FILESYSTEM__RELABELFROM, NULL);
332 if (rc)
333 return rc;
334
335 rc = avc_has_perm(tsec->sid, sid, SECCLASS_FILESYSTEM,
336 FILESYSTEM__RELABELTO, NULL);
337 return rc;
338 }
339
340 static int may_context_mount_inode_relabel(u32 sid,
341 struct superblock_security_struct *sbsec,
342 const struct cred *cred)
343 {
344 const struct task_security_struct *tsec = cred->security;
345 int rc;
346 rc = avc_has_perm(tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM,
347 FILESYSTEM__RELABELFROM, NULL);
348 if (rc)
349 return rc;
350
351 rc = avc_has_perm(sid, sbsec->sid, SECCLASS_FILESYSTEM,
352 FILESYSTEM__ASSOCIATE, NULL);
353 return rc;
354 }
355
356 static int sb_finish_set_opts(struct super_block *sb)
357 {
358 struct superblock_security_struct *sbsec = sb->s_security;
359 struct dentry *root = sb->s_root;
360 struct inode *root_inode = root->d_inode;
361 int rc = 0;
362
363 if (sbsec->behavior == SECURITY_FS_USE_XATTR) {
364 /* Make sure that the xattr handler exists and that no
365 error other than -ENODATA is returned by getxattr on
366 the root directory. -ENODATA is ok, as this may be
367 the first boot of the SELinux kernel before we have
368 assigned xattr values to the filesystem. */
369 if (!root_inode->i_op->getxattr) {
370 printk(KERN_WARNING "SELinux: (dev %s, type %s) has no "
371 "xattr support\n", sb->s_id, sb->s_type->name);
372 rc = -EOPNOTSUPP;
373 goto out;
374 }
375 rc = root_inode->i_op->getxattr(root, XATTR_NAME_SELINUX, NULL, 0);
376 if (rc < 0 && rc != -ENODATA) {
377 if (rc == -EOPNOTSUPP)
378 printk(KERN_WARNING "SELinux: (dev %s, type "
379 "%s) has no security xattr handler\n",
380 sb->s_id, sb->s_type->name);
381 else
382 printk(KERN_WARNING "SELinux: (dev %s, type "
383 "%s) getxattr errno %d\n", sb->s_id,
384 sb->s_type->name, -rc);
385 goto out;
386 }
387 }
388
389 sbsec->flags |= (SE_SBINITIALIZED | SE_SBLABELSUPP);
390
391 if (sbsec->behavior > ARRAY_SIZE(labeling_behaviors))
392 printk(KERN_ERR "SELinux: initialized (dev %s, type %s), unknown behavior\n",
393 sb->s_id, sb->s_type->name);
394 else
395 printk(KERN_DEBUG "SELinux: initialized (dev %s, type %s), %s\n",
396 sb->s_id, sb->s_type->name,
397 labeling_behaviors[sbsec->behavior-1]);
398
399 if (sbsec->behavior == SECURITY_FS_USE_GENFS ||
400 sbsec->behavior == SECURITY_FS_USE_MNTPOINT ||
401 sbsec->behavior == SECURITY_FS_USE_NONE ||
402 sbsec->behavior > ARRAY_SIZE(labeling_behaviors))
403 sbsec->flags &= ~SE_SBLABELSUPP;
404
405 /* Special handling for sysfs. Is genfs but also has setxattr handler*/
406 if (strncmp(sb->s_type->name, "sysfs", sizeof("sysfs")) == 0)
407 sbsec->flags |= SE_SBLABELSUPP;
408
409 /* Initialize the root inode. */
410 rc = inode_doinit_with_dentry(root_inode, root);
411
412 /* Initialize any other inodes associated with the superblock, e.g.
413 inodes created prior to initial policy load or inodes created
414 during get_sb by a pseudo filesystem that directly
415 populates itself. */
416 spin_lock(&sbsec->isec_lock);
417 next_inode:
418 if (!list_empty(&sbsec->isec_head)) {
419 struct inode_security_struct *isec =
420 list_entry(sbsec->isec_head.next,
421 struct inode_security_struct, list);
422 struct inode *inode = isec->inode;
423 spin_unlock(&sbsec->isec_lock);
424 inode = igrab(inode);
425 if (inode) {
426 if (!IS_PRIVATE(inode))
427 inode_doinit(inode);
428 iput(inode);
429 }
430 spin_lock(&sbsec->isec_lock);
431 list_del_init(&isec->list);
432 goto next_inode;
433 }
434 spin_unlock(&sbsec->isec_lock);
435 out:
436 return rc;
437 }
438
439 /*
440 * This function should allow an FS to ask what it's mount security
441 * options were so it can use those later for submounts, displaying
442 * mount options, or whatever.
443 */
444 static int selinux_get_mnt_opts(const struct super_block *sb,
445 struct security_mnt_opts *opts)
446 {
447 int rc = 0, i;
448 struct superblock_security_struct *sbsec = sb->s_security;
449 char *context = NULL;
450 u32 len;
451 char tmp;
452
453 security_init_mnt_opts(opts);
454
455 if (!(sbsec->flags & SE_SBINITIALIZED))
456 return -EINVAL;
457
458 if (!ss_initialized)
459 return -EINVAL;
460
461 tmp = sbsec->flags & SE_MNTMASK;
462 /* count the number of mount options for this sb */
463 for (i = 0; i < 8; i++) {
464 if (tmp & 0x01)
465 opts->num_mnt_opts++;
466 tmp >>= 1;
467 }
468 /* Check if the Label support flag is set */
469 if (sbsec->flags & SE_SBLABELSUPP)
470 opts->num_mnt_opts++;
471
472 opts->mnt_opts = kcalloc(opts->num_mnt_opts, sizeof(char *), GFP_ATOMIC);
473 if (!opts->mnt_opts) {
474 rc = -ENOMEM;
475 goto out_free;
476 }
477
478 opts->mnt_opts_flags = kcalloc(opts->num_mnt_opts, sizeof(int), GFP_ATOMIC);
479 if (!opts->mnt_opts_flags) {
480 rc = -ENOMEM;
481 goto out_free;
482 }
483
484 i = 0;
485 if (sbsec->flags & FSCONTEXT_MNT) {
486 rc = security_sid_to_context(sbsec->sid, &context, &len);
487 if (rc)
488 goto out_free;
489 opts->mnt_opts[i] = context;
490 opts->mnt_opts_flags[i++] = FSCONTEXT_MNT;
491 }
492 if (sbsec->flags & CONTEXT_MNT) {
493 rc = security_sid_to_context(sbsec->mntpoint_sid, &context, &len);
494 if (rc)
495 goto out_free;
496 opts->mnt_opts[i] = context;
497 opts->mnt_opts_flags[i++] = CONTEXT_MNT;
498 }
499 if (sbsec->flags & DEFCONTEXT_MNT) {
500 rc = security_sid_to_context(sbsec->def_sid, &context, &len);
501 if (rc)
502 goto out_free;
503 opts->mnt_opts[i] = context;
504 opts->mnt_opts_flags[i++] = DEFCONTEXT_MNT;
505 }
506 if (sbsec->flags & ROOTCONTEXT_MNT) {
507 struct inode *root = sbsec->sb->s_root->d_inode;
508 struct inode_security_struct *isec = root->i_security;
509
510 rc = security_sid_to_context(isec->sid, &context, &len);
511 if (rc)
512 goto out_free;
513 opts->mnt_opts[i] = context;
514 opts->mnt_opts_flags[i++] = ROOTCONTEXT_MNT;
515 }
516 if (sbsec->flags & SE_SBLABELSUPP) {
517 opts->mnt_opts[i] = NULL;
518 opts->mnt_opts_flags[i++] = SE_SBLABELSUPP;
519 }
520
521 BUG_ON(i != opts->num_mnt_opts);
522
523 return 0;
524
525 out_free:
526 security_free_mnt_opts(opts);
527 return rc;
528 }
529
530 static int bad_option(struct superblock_security_struct *sbsec, char flag,
531 u32 old_sid, u32 new_sid)
532 {
533 char mnt_flags = sbsec->flags & SE_MNTMASK;
534
535 /* check if the old mount command had the same options */
536 if (sbsec->flags & SE_SBINITIALIZED)
537 if (!(sbsec->flags & flag) ||
538 (old_sid != new_sid))
539 return 1;
540
541 /* check if we were passed the same options twice,
542 * aka someone passed context=a,context=b
543 */
544 if (!(sbsec->flags & SE_SBINITIALIZED))
545 if (mnt_flags & flag)
546 return 1;
547 return 0;
548 }
549
550 /*
551 * Allow filesystems with binary mount data to explicitly set mount point
552 * labeling information.
553 */
554 static int selinux_set_mnt_opts(struct super_block *sb,
555 struct security_mnt_opts *opts)
556 {
557 const struct cred *cred = current_cred();
558 int rc = 0, i;
559 struct superblock_security_struct *sbsec = sb->s_security;
560 const char *name = sb->s_type->name;
561 struct inode *inode = sbsec->sb->s_root->d_inode;
562 struct inode_security_struct *root_isec = inode->i_security;
563 u32 fscontext_sid = 0, context_sid = 0, rootcontext_sid = 0;
564 u32 defcontext_sid = 0;
565 char **mount_options = opts->mnt_opts;
566 int *flags = opts->mnt_opts_flags;
567 int num_opts = opts->num_mnt_opts;
568
569 mutex_lock(&sbsec->lock);
570
571 if (!ss_initialized) {
572 if (!num_opts) {
573 /* Defer initialization until selinux_complete_init,
574 after the initial policy is loaded and the security
575 server is ready to handle calls. */
576 goto out;
577 }
578 rc = -EINVAL;
579 printk(KERN_WARNING "SELinux: Unable to set superblock options "
580 "before the security server is initialized\n");
581 goto out;
582 }
583
584 /*
585 * Binary mount data FS will come through this function twice. Once
586 * from an explicit call and once from the generic calls from the vfs.
587 * Since the generic VFS calls will not contain any security mount data
588 * we need to skip the double mount verification.
589 *
590 * This does open a hole in which we will not notice if the first
591 * mount using this sb set explict options and a second mount using
592 * this sb does not set any security options. (The first options
593 * will be used for both mounts)
594 */
595 if ((sbsec->flags & SE_SBINITIALIZED) && (sb->s_type->fs_flags & FS_BINARY_MOUNTDATA)
596 && (num_opts == 0))
597 goto out;
598
599 /*
600 * parse the mount options, check if they are valid sids.
601 * also check if someone is trying to mount the same sb more
602 * than once with different security options.
603 */
604 for (i = 0; i < num_opts; i++) {
605 u32 sid;
606
607 if (flags[i] == SE_SBLABELSUPP)
608 continue;
609 rc = security_context_to_sid(mount_options[i],
610 strlen(mount_options[i]), &sid);
611 if (rc) {
612 printk(KERN_WARNING "SELinux: security_context_to_sid"
613 "(%s) failed for (dev %s, type %s) errno=%d\n",
614 mount_options[i], sb->s_id, name, rc);
615 goto out;
616 }
617 switch (flags[i]) {
618 case FSCONTEXT_MNT:
619 fscontext_sid = sid;
620
621 if (bad_option(sbsec, FSCONTEXT_MNT, sbsec->sid,
622 fscontext_sid))
623 goto out_double_mount;
624
625 sbsec->flags |= FSCONTEXT_MNT;
626 break;
627 case CONTEXT_MNT:
628 context_sid = sid;
629
630 if (bad_option(sbsec, CONTEXT_MNT, sbsec->mntpoint_sid,
631 context_sid))
632 goto out_double_mount;
633
634 sbsec->flags |= CONTEXT_MNT;
635 break;
636 case ROOTCONTEXT_MNT:
637 rootcontext_sid = sid;
638
639 if (bad_option(sbsec, ROOTCONTEXT_MNT, root_isec->sid,
640 rootcontext_sid))
641 goto out_double_mount;
642
643 sbsec->flags |= ROOTCONTEXT_MNT;
644
645 break;
646 case DEFCONTEXT_MNT:
647 defcontext_sid = sid;
648
649 if (bad_option(sbsec, DEFCONTEXT_MNT, sbsec->def_sid,
650 defcontext_sid))
651 goto out_double_mount;
652
653 sbsec->flags |= DEFCONTEXT_MNT;
654
655 break;
656 default:
657 rc = -EINVAL;
658 goto out;
659 }
660 }
661
662 if (sbsec->flags & SE_SBINITIALIZED) {
663 /* previously mounted with options, but not on this attempt? */
664 if ((sbsec->flags & SE_MNTMASK) && !num_opts)
665 goto out_double_mount;
666 rc = 0;
667 goto out;
668 }
669
670 if (strcmp(sb->s_type->name, "proc") == 0)
671 sbsec->flags |= SE_SBPROC;
672
673 /* Determine the labeling behavior to use for this filesystem type. */
674 rc = security_fs_use((sbsec->flags & SE_SBPROC) ? "proc" : sb->s_type->name, &sbsec->behavior, &sbsec->sid);
675 if (rc) {
676 printk(KERN_WARNING "%s: security_fs_use(%s) returned %d\n",
677 __func__, sb->s_type->name, rc);
678 goto out;
679 }
680
681 /* sets the context of the superblock for the fs being mounted. */
682 if (fscontext_sid) {
683 rc = may_context_mount_sb_relabel(fscontext_sid, sbsec, cred);
684 if (rc)
685 goto out;
686
687 sbsec->sid = fscontext_sid;
688 }
689
690 /*
691 * Switch to using mount point labeling behavior.
692 * sets the label used on all file below the mountpoint, and will set
693 * the superblock context if not already set.
694 */
695 if (context_sid) {
696 if (!fscontext_sid) {
697 rc = may_context_mount_sb_relabel(context_sid, sbsec,
698 cred);
699 if (rc)
700 goto out;
701 sbsec->sid = context_sid;
702 } else {
703 rc = may_context_mount_inode_relabel(context_sid, sbsec,
704 cred);
705 if (rc)
706 goto out;
707 }
708 if (!rootcontext_sid)
709 rootcontext_sid = context_sid;
710
711 sbsec->mntpoint_sid = context_sid;
712 sbsec->behavior = SECURITY_FS_USE_MNTPOINT;
713 }
714
715 if (rootcontext_sid) {
716 rc = may_context_mount_inode_relabel(rootcontext_sid, sbsec,
717 cred);
718 if (rc)
719 goto out;
720
721 root_isec->sid = rootcontext_sid;
722 root_isec->initialized = 1;
723 }
724
725 if (defcontext_sid) {
726 if (sbsec->behavior != SECURITY_FS_USE_XATTR) {
727 rc = -EINVAL;
728 printk(KERN_WARNING "SELinux: defcontext option is "
729 "invalid for this filesystem type\n");
730 goto out;
731 }
732
733 if (defcontext_sid != sbsec->def_sid) {
734 rc = may_context_mount_inode_relabel(defcontext_sid,
735 sbsec, cred);
736 if (rc)
737 goto out;
738 }
739
740 sbsec->def_sid = defcontext_sid;
741 }
742
743 rc = sb_finish_set_opts(sb);
744 out:
745 mutex_unlock(&sbsec->lock);
746 return rc;
747 out_double_mount:
748 rc = -EINVAL;
749 printk(KERN_WARNING "SELinux: mount invalid. Same superblock, different "
750 "security settings for (dev %s, type %s)\n", sb->s_id, name);
751 goto out;
752 }
753
754 static int selinux_cmp_sb_context(const struct super_block *oldsb,
755 const struct super_block *newsb)
756 {
757 struct superblock_security_struct *old = oldsb->s_security;
758 struct superblock_security_struct *new = newsb->s_security;
759 char oldflags = old->flags & SE_MNTMASK;
760 char newflags = new->flags & SE_MNTMASK;
761
762 if (oldflags != newflags)
763 goto mismatch;
764 if ((oldflags & FSCONTEXT_MNT) && old->sid != new->sid)
765 goto mismatch;
766 if ((oldflags & CONTEXT_MNT) && old->mntpoint_sid != new->mntpoint_sid)
767 goto mismatch;
768 if ((oldflags & DEFCONTEXT_MNT) && old->def_sid != new->def_sid)
769 goto mismatch;
770 if (oldflags & ROOTCONTEXT_MNT) {
771 struct inode_security_struct *oldroot = oldsb->s_root->d_inode->i_security;
772 struct inode_security_struct *newroot = newsb->s_root->d_inode->i_security;
773 if (oldroot->sid != newroot->sid)
774 goto mismatch;
775 }
776 return 0;
777 mismatch:
778 printk(KERN_WARNING "SELinux: mount invalid. Same superblock, "
779 "different security settings for (dev %s, "
780 "type %s)\n", newsb->s_id, newsb->s_type->name);
781 return -EBUSY;
782 }
783
784 static int selinux_sb_clone_mnt_opts(const struct super_block *oldsb,
785 struct super_block *newsb)
786 {
787 const struct superblock_security_struct *oldsbsec = oldsb->s_security;
788 struct superblock_security_struct *newsbsec = newsb->s_security;
789
790 int set_fscontext = (oldsbsec->flags & FSCONTEXT_MNT);
791 int set_context = (oldsbsec->flags & CONTEXT_MNT);
792 int set_rootcontext = (oldsbsec->flags & ROOTCONTEXT_MNT);
793
794 /*
795 * if the parent was able to be mounted it clearly had no special lsm
796 * mount options. thus we can safely deal with this superblock later
797 */
798 if (!ss_initialized)
799 return 0;
800
801 /* how can we clone if the old one wasn't set up?? */
802 BUG_ON(!(oldsbsec->flags & SE_SBINITIALIZED));
803
804 /* if fs is reusing a sb, make sure that the contexts match */
805 if (newsbsec->flags & SE_SBINITIALIZED)
806 return selinux_cmp_sb_context(oldsb, newsb);
807
808 mutex_lock(&newsbsec->lock);
809
810 newsbsec->flags = oldsbsec->flags;
811
812 newsbsec->sid = oldsbsec->sid;
813 newsbsec->def_sid = oldsbsec->def_sid;
814 newsbsec->behavior = oldsbsec->behavior;
815
816 if (set_context) {
817 u32 sid = oldsbsec->mntpoint_sid;
818
819 if (!set_fscontext)
820 newsbsec->sid = sid;
821 if (!set_rootcontext) {
822 struct inode *newinode = newsb->s_root->d_inode;
823 struct inode_security_struct *newisec = newinode->i_security;
824 newisec->sid = sid;
825 }
826 newsbsec->mntpoint_sid = sid;
827 }
828 if (set_rootcontext) {
829 const struct inode *oldinode = oldsb->s_root->d_inode;
830 const struct inode_security_struct *oldisec = oldinode->i_security;
831 struct inode *newinode = newsb->s_root->d_inode;
832 struct inode_security_struct *newisec = newinode->i_security;
833
834 newisec->sid = oldisec->sid;
835 }
836
837 sb_finish_set_opts(newsb);
838 mutex_unlock(&newsbsec->lock);
839 return 0;
840 }
841
842 static int selinux_parse_opts_str(char *options,
843 struct security_mnt_opts *opts)
844 {
845 char *p;
846 char *context = NULL, *defcontext = NULL;
847 char *fscontext = NULL, *rootcontext = NULL;
848 int rc, num_mnt_opts = 0;
849
850 opts->num_mnt_opts = 0;
851
852 /* Standard string-based options. */
853 while ((p = strsep(&options, "|")) != NULL) {
854 int token;
855 substring_t args[MAX_OPT_ARGS];
856
857 if (!*p)
858 continue;
859
860 token = match_token(p, tokens, args);
861
862 switch (token) {
863 case Opt_context:
864 if (context || defcontext) {
865 rc = -EINVAL;
866 printk(KERN_WARNING SEL_MOUNT_FAIL_MSG);
867 goto out_err;
868 }
869 context = match_strdup(&args[0]);
870 if (!context) {
871 rc = -ENOMEM;
872 goto out_err;
873 }
874 break;
875
876 case Opt_fscontext:
877 if (fscontext) {
878 rc = -EINVAL;
879 printk(KERN_WARNING SEL_MOUNT_FAIL_MSG);
880 goto out_err;
881 }
882 fscontext = match_strdup(&args[0]);
883 if (!fscontext) {
884 rc = -ENOMEM;
885 goto out_err;
886 }
887 break;
888
889 case Opt_rootcontext:
890 if (rootcontext) {
891 rc = -EINVAL;
892 printk(KERN_WARNING SEL_MOUNT_FAIL_MSG);
893 goto out_err;
894 }
895 rootcontext = match_strdup(&args[0]);
896 if (!rootcontext) {
897 rc = -ENOMEM;
898 goto out_err;
899 }
900 break;
901
902 case Opt_defcontext:
903 if (context || defcontext) {
904 rc = -EINVAL;
905 printk(KERN_WARNING SEL_MOUNT_FAIL_MSG);
906 goto out_err;
907 }
908 defcontext = match_strdup(&args[0]);
909 if (!defcontext) {
910 rc = -ENOMEM;
911 goto out_err;
912 }
913 break;
914 case Opt_labelsupport:
915 break;
916 default:
917 rc = -EINVAL;
918 printk(KERN_WARNING "SELinux: unknown mount option\n");
919 goto out_err;
920
921 }
922 }
923
924 rc = -ENOMEM;
925 opts->mnt_opts = kcalloc(NUM_SEL_MNT_OPTS, sizeof(char *), GFP_ATOMIC);
926 if (!opts->mnt_opts)
927 goto out_err;
928
929 opts->mnt_opts_flags = kcalloc(NUM_SEL_MNT_OPTS, sizeof(int), GFP_ATOMIC);
930 if (!opts->mnt_opts_flags) {
931 kfree(opts->mnt_opts);
932 goto out_err;
933 }
934
935 if (fscontext) {
936 opts->mnt_opts[num_mnt_opts] = fscontext;
937 opts->mnt_opts_flags[num_mnt_opts++] = FSCONTEXT_MNT;
938 }
939 if (context) {
940 opts->mnt_opts[num_mnt_opts] = context;
941 opts->mnt_opts_flags[num_mnt_opts++] = CONTEXT_MNT;
942 }
943 if (rootcontext) {
944 opts->mnt_opts[num_mnt_opts] = rootcontext;
945 opts->mnt_opts_flags[num_mnt_opts++] = ROOTCONTEXT_MNT;
946 }
947 if (defcontext) {
948 opts->mnt_opts[num_mnt_opts] = defcontext;
949 opts->mnt_opts_flags[num_mnt_opts++] = DEFCONTEXT_MNT;
950 }
951
952 opts->num_mnt_opts = num_mnt_opts;
953 return 0;
954
955 out_err:
956 kfree(context);
957 kfree(defcontext);
958 kfree(fscontext);
959 kfree(rootcontext);
960 return rc;
961 }
962 /*
963 * string mount options parsing and call set the sbsec
964 */
965 static int superblock_doinit(struct super_block *sb, void *data)
966 {
967 int rc = 0;
968 char *options = data;
969 struct security_mnt_opts opts;
970
971 security_init_mnt_opts(&opts);
972
973 if (!data)
974 goto out;
975
976 BUG_ON(sb->s_type->fs_flags & FS_BINARY_MOUNTDATA);
977
978 rc = selinux_parse_opts_str(options, &opts);
979 if (rc)
980 goto out_err;
981
982 out:
983 rc = selinux_set_mnt_opts(sb, &opts);
984
985 out_err:
986 security_free_mnt_opts(&opts);
987 return rc;
988 }
989
990 static void selinux_write_opts(struct seq_file *m,
991 struct security_mnt_opts *opts)
992 {
993 int i;
994 char *prefix;
995
996 for (i = 0; i < opts->num_mnt_opts; i++) {
997 char *has_comma;
998
999 if (opts->mnt_opts[i])
1000 has_comma = strchr(opts->mnt_opts[i], ',');
1001 else
1002 has_comma = NULL;
1003
1004 switch (opts->mnt_opts_flags[i]) {
1005 case CONTEXT_MNT:
1006 prefix = CONTEXT_STR;
1007 break;
1008 case FSCONTEXT_MNT:
1009 prefix = FSCONTEXT_STR;
1010 break;
1011 case ROOTCONTEXT_MNT:
1012 prefix = ROOTCONTEXT_STR;
1013 break;
1014 case DEFCONTEXT_MNT:
1015 prefix = DEFCONTEXT_STR;
1016 break;
1017 case SE_SBLABELSUPP:
1018 seq_putc(m, ',');
1019 seq_puts(m, LABELSUPP_STR);
1020 continue;
1021 default:
1022 BUG();
1023 return;
1024 };
1025 /* we need a comma before each option */
1026 seq_putc(m, ',');
1027 seq_puts(m, prefix);
1028 if (has_comma)
1029 seq_putc(m, '\"');
1030 seq_puts(m, opts->mnt_opts[i]);
1031 if (has_comma)
1032 seq_putc(m, '\"');
1033 }
1034 }
1035
1036 static int selinux_sb_show_options(struct seq_file *m, struct super_block *sb)
1037 {
1038 struct security_mnt_opts opts;
1039 int rc;
1040
1041 rc = selinux_get_mnt_opts(sb, &opts);
1042 if (rc) {
1043 /* before policy load we may get EINVAL, don't show anything */
1044 if (rc == -EINVAL)
1045 rc = 0;
1046 return rc;
1047 }
1048
1049 selinux_write_opts(m, &opts);
1050
1051 security_free_mnt_opts(&opts);
1052
1053 return rc;
1054 }
1055
1056 static inline u16 inode_mode_to_security_class(umode_t mode)
1057 {
1058 switch (mode & S_IFMT) {
1059 case S_IFSOCK:
1060 return SECCLASS_SOCK_FILE;
1061 case S_IFLNK:
1062 return SECCLASS_LNK_FILE;
1063 case S_IFREG:
1064 return SECCLASS_FILE;
1065 case S_IFBLK:
1066 return SECCLASS_BLK_FILE;
1067 case S_IFDIR:
1068 return SECCLASS_DIR;
1069 case S_IFCHR:
1070 return SECCLASS_CHR_FILE;
1071 case S_IFIFO:
1072 return SECCLASS_FIFO_FILE;
1073
1074 }
1075
1076 return SECCLASS_FILE;
1077 }
1078
1079 static inline int default_protocol_stream(int protocol)
1080 {
1081 return (protocol == IPPROTO_IP || protocol == IPPROTO_TCP);
1082 }
1083
1084 static inline int default_protocol_dgram(int protocol)
1085 {
1086 return (protocol == IPPROTO_IP || protocol == IPPROTO_UDP);
1087 }
1088
1089 static inline u16 socket_type_to_security_class(int family, int type, int protocol)
1090 {
1091 switch (family) {
1092 case PF_UNIX:
1093 switch (type) {
1094 case SOCK_STREAM:
1095 case SOCK_SEQPACKET:
1096 return SECCLASS_UNIX_STREAM_SOCKET;
1097 case SOCK_DGRAM:
1098 return SECCLASS_UNIX_DGRAM_SOCKET;
1099 }
1100 break;
1101 case PF_INET:
1102 case PF_INET6:
1103 switch (type) {
1104 case SOCK_STREAM:
1105 if (default_protocol_stream(protocol))
1106 return SECCLASS_TCP_SOCKET;
1107 else
1108 return SECCLASS_RAWIP_SOCKET;
1109 case SOCK_DGRAM:
1110 if (default_protocol_dgram(protocol))
1111 return SECCLASS_UDP_SOCKET;
1112 else
1113 return SECCLASS_RAWIP_SOCKET;
1114 case SOCK_DCCP:
1115 return SECCLASS_DCCP_SOCKET;
1116 default:
1117 return SECCLASS_RAWIP_SOCKET;
1118 }
1119 break;
1120 case PF_NETLINK:
1121 switch (protocol) {
1122 case NETLINK_ROUTE:
1123 return SECCLASS_NETLINK_ROUTE_SOCKET;
1124 case NETLINK_FIREWALL:
1125 return SECCLASS_NETLINK_FIREWALL_SOCKET;
1126 case NETLINK_SOCK_DIAG:
1127 return SECCLASS_NETLINK_TCPDIAG_SOCKET;
1128 case NETLINK_NFLOG:
1129 return SECCLASS_NETLINK_NFLOG_SOCKET;
1130 case NETLINK_XFRM:
1131 return SECCLASS_NETLINK_XFRM_SOCKET;
1132 case NETLINK_SELINUX:
1133 return SECCLASS_NETLINK_SELINUX_SOCKET;
1134 case NETLINK_AUDIT:
1135 return SECCLASS_NETLINK_AUDIT_SOCKET;
1136 case NETLINK_IP6_FW:
1137 return SECCLASS_NETLINK_IP6FW_SOCKET;
1138 case NETLINK_DNRTMSG:
1139 return SECCLASS_NETLINK_DNRT_SOCKET;
1140 case NETLINK_KOBJECT_UEVENT:
1141 return SECCLASS_NETLINK_KOBJECT_UEVENT_SOCKET;
1142 default:
1143 return SECCLASS_NETLINK_SOCKET;
1144 }
1145 case PF_PACKET:
1146 return SECCLASS_PACKET_SOCKET;
1147 case PF_KEY:
1148 return SECCLASS_KEY_SOCKET;
1149 case PF_APPLETALK:
1150 return SECCLASS_APPLETALK_SOCKET;
1151 }
1152
1153 return SECCLASS_SOCKET;
1154 }
1155
1156 #ifdef CONFIG_PROC_FS
1157 static int selinux_proc_get_sid(struct dentry *dentry,
1158 u16 tclass,
1159 u32 *sid)
1160 {
1161 int rc;
1162 char *buffer, *path;
1163
1164 buffer = (char *)__get_free_page(GFP_KERNEL);
1165 if (!buffer)
1166 return -ENOMEM;
1167
1168 path = dentry_path_raw(dentry, buffer, PAGE_SIZE);
1169 if (IS_ERR(path))
1170 rc = PTR_ERR(path);
1171 else {
1172 /* each process gets a /proc/PID/ entry. Strip off the
1173 * PID part to get a valid selinux labeling.
1174 * e.g. /proc/1/net/rpc/nfs -> /net/rpc/nfs */
1175 while (path[1] >= '0' && path[1] <= '9') {
1176 path[1] = '/';
1177 path++;
1178 }
1179 rc = security_genfs_sid("proc", path, tclass, sid);
1180 }
1181 free_page((unsigned long)buffer);
1182 return rc;
1183 }
1184 #else
1185 static int selinux_proc_get_sid(struct dentry *dentry,
1186 u16 tclass,
1187 u32 *sid)
1188 {
1189 return -EINVAL;
1190 }
1191 #endif
1192
1193 /* The inode's security attributes must be initialized before first use. */
1194 static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dentry)
1195 {
1196 struct superblock_security_struct *sbsec = NULL;
1197 struct inode_security_struct *isec = inode->i_security;
1198 u32 sid;
1199 struct dentry *dentry;
1200 #define INITCONTEXTLEN 255
1201 char *context = NULL;
1202 unsigned len = 0;
1203 int rc = 0;
1204
1205 if (isec->initialized)
1206 goto out;
1207
1208 mutex_lock(&isec->lock);
1209 if (isec->initialized)
1210 goto out_unlock;
1211
1212 sbsec = inode->i_sb->s_security;
1213 if (!(sbsec->flags & SE_SBINITIALIZED)) {
1214 /* Defer initialization until selinux_complete_init,
1215 after the initial policy is loaded and the security
1216 server is ready to handle calls. */
1217 spin_lock(&sbsec->isec_lock);
1218 if (list_empty(&isec->list))
1219 list_add(&isec->list, &sbsec->isec_head);
1220 spin_unlock(&sbsec->isec_lock);
1221 goto out_unlock;
1222 }
1223
1224 switch (sbsec->behavior) {
1225 case SECURITY_FS_USE_XATTR:
1226 if (!inode->i_op->getxattr) {
1227 isec->sid = sbsec->def_sid;
1228 break;
1229 }
1230
1231 /* Need a dentry, since the xattr API requires one.
1232 Life would be simpler if we could just pass the inode. */
1233 if (opt_dentry) {
1234 /* Called from d_instantiate or d_splice_alias. */
1235 dentry = dget(opt_dentry);
1236 } else {
1237 /* Called from selinux_complete_init, try to find a dentry. */
1238 dentry = d_find_alias(inode);
1239 }
1240 if (!dentry) {
1241 /*
1242 * this is can be hit on boot when a file is accessed
1243 * before the policy is loaded. When we load policy we
1244 * may find inodes that have no dentry on the
1245 * sbsec->isec_head list. No reason to complain as these
1246 * will get fixed up the next time we go through
1247 * inode_doinit with a dentry, before these inodes could
1248 * be used again by userspace.
1249 */
1250 goto out_unlock;
1251 }
1252
1253 len = INITCONTEXTLEN;
1254 context = kmalloc(len+1, GFP_NOFS);
1255 if (!context) {
1256 rc = -ENOMEM;
1257 dput(dentry);
1258 goto out_unlock;
1259 }
1260 context[len] = '\0';
1261 rc = inode->i_op->getxattr(dentry, XATTR_NAME_SELINUX,
1262 context, len);
1263 if (rc == -ERANGE) {
1264 kfree(context);
1265
1266 /* Need a larger buffer. Query for the right size. */
1267 rc = inode->i_op->getxattr(dentry, XATTR_NAME_SELINUX,
1268 NULL, 0);
1269 if (rc < 0) {
1270 dput(dentry);
1271 goto out_unlock;
1272 }
1273 len = rc;
1274 context = kmalloc(len+1, GFP_NOFS);
1275 if (!context) {
1276 rc = -ENOMEM;
1277 dput(dentry);
1278 goto out_unlock;
1279 }
1280 context[len] = '\0';
1281 rc = inode->i_op->getxattr(dentry,
1282 XATTR_NAME_SELINUX,
1283 context, len);
1284 }
1285 dput(dentry);
1286 if (rc < 0) {
1287 if (rc != -ENODATA) {
1288 printk(KERN_WARNING "SELinux: %s: getxattr returned "
1289 "%d for dev=%s ino=%ld\n", __func__,
1290 -rc, inode->i_sb->s_id, inode->i_ino);
1291 kfree(context);
1292 goto out_unlock;
1293 }
1294 /* Map ENODATA to the default file SID */
1295 sid = sbsec->def_sid;
1296 rc = 0;
1297 } else {
1298 rc = security_context_to_sid_default(context, rc, &sid,
1299 sbsec->def_sid,
1300 GFP_NOFS);
1301 if (rc) {
1302 char *dev = inode->i_sb->s_id;
1303 unsigned long ino = inode->i_ino;
1304
1305 if (rc == -EINVAL) {
1306 if (printk_ratelimit())
1307 printk(KERN_NOTICE "SELinux: inode=%lu on dev=%s was found to have an invalid "
1308 "context=%s. This indicates you may need to relabel the inode or the "
1309 "filesystem in question.\n", ino, dev, context);
1310 } else {
1311 printk(KERN_WARNING "SELinux: %s: context_to_sid(%s) "
1312 "returned %d for dev=%s ino=%ld\n",
1313 __func__, context, -rc, dev, ino);
1314 }
1315 kfree(context);
1316 /* Leave with the unlabeled SID */
1317 rc = 0;
1318 break;
1319 }
1320 }
1321 kfree(context);
1322 isec->sid = sid;
1323 break;
1324 case SECURITY_FS_USE_TASK:
1325 isec->sid = isec->task_sid;
1326 break;
1327 case SECURITY_FS_USE_TRANS:
1328 /* Default to the fs SID. */
1329 isec->sid = sbsec->sid;
1330
1331 /* Try to obtain a transition SID. */
1332 isec->sclass = inode_mode_to_security_class(inode->i_mode);
1333 rc = security_transition_sid(isec->task_sid, sbsec->sid,
1334 isec->sclass, NULL, &sid);
1335 if (rc)
1336 goto out_unlock;
1337 isec->sid = sid;
1338 break;
1339 case SECURITY_FS_USE_MNTPOINT:
1340 isec->sid = sbsec->mntpoint_sid;
1341 break;
1342 default:
1343 /* Default to the fs superblock SID. */
1344 isec->sid = sbsec->sid;
1345
1346 if ((sbsec->flags & SE_SBPROC) && !S_ISLNK(inode->i_mode)) {
1347 if (opt_dentry) {
1348 isec->sclass = inode_mode_to_security_class(inode->i_mode);
1349 rc = selinux_proc_get_sid(opt_dentry,
1350 isec->sclass,
1351 &sid);
1352 if (rc)
1353 goto out_unlock;
1354 isec->sid = sid;
1355 }
1356 }
1357 break;
1358 }
1359
1360 isec->initialized = 1;
1361
1362 out_unlock:
1363 mutex_unlock(&isec->lock);
1364 out:
1365 if (isec->sclass == SECCLASS_FILE)
1366 isec->sclass = inode_mode_to_security_class(inode->i_mode);
1367 return rc;
1368 }
1369
1370 /* Convert a Linux signal to an access vector. */
1371 static inline u32 signal_to_av(int sig)
1372 {
1373 u32 perm = 0;
1374
1375 switch (sig) {
1376 case SIGCHLD:
1377 /* Commonly granted from child to parent. */
1378 perm = PROCESS__SIGCHLD;
1379 break;
1380 case SIGKILL:
1381 /* Cannot be caught or ignored */
1382 perm = PROCESS__SIGKILL;
1383 break;
1384 case SIGSTOP:
1385 /* Cannot be caught or ignored */
1386 perm = PROCESS__SIGSTOP;
1387 break;
1388 default:
1389 /* All other signals. */
1390 perm = PROCESS__SIGNAL;
1391 break;
1392 }
1393
1394 return perm;
1395 }
1396
1397 /*
1398 * Check permission between a pair of credentials
1399 * fork check, ptrace check, etc.
1400 */
1401 static int cred_has_perm(const struct cred *actor,
1402 const struct cred *target,
1403 u32 perms)
1404 {
1405 u32 asid = cred_sid(actor), tsid = cred_sid(target);
1406
1407 return avc_has_perm(asid, tsid, SECCLASS_PROCESS, perms, NULL);
1408 }
1409
1410 /*
1411 * Check permission between a pair of tasks, e.g. signal checks,
1412 * fork check, ptrace check, etc.
1413 * tsk1 is the actor and tsk2 is the target
1414 * - this uses the default subjective creds of tsk1
1415 */
1416 static int task_has_perm(const struct task_struct *tsk1,
1417 const struct task_struct *tsk2,
1418 u32 perms)
1419 {
1420 const struct task_security_struct *__tsec1, *__tsec2;
1421 u32 sid1, sid2;
1422
1423 rcu_read_lock();
1424 __tsec1 = __task_cred(tsk1)->security; sid1 = __tsec1->sid;
1425 __tsec2 = __task_cred(tsk2)->security; sid2 = __tsec2->sid;
1426 rcu_read_unlock();
1427 return avc_has_perm(sid1, sid2, SECCLASS_PROCESS, perms, NULL);
1428 }
1429
1430 /*
1431 * Check permission between current and another task, e.g. signal checks,
1432 * fork check, ptrace check, etc.
1433 * current is the actor and tsk2 is the target
1434 * - this uses current's subjective creds
1435 */
1436 static int current_has_perm(const struct task_struct *tsk,
1437 u32 perms)
1438 {
1439 u32 sid, tsid;
1440
1441 sid = current_sid();
1442 tsid = task_sid(tsk);
1443 return avc_has_perm(sid, tsid, SECCLASS_PROCESS, perms, NULL);
1444 }
1445
1446 #if CAP_LAST_CAP > 63
1447 #error Fix SELinux to handle capabilities > 63.
1448 #endif
1449
1450 /* Check whether a task is allowed to use a capability. */
1451 static int cred_has_capability(const struct cred *cred,
1452 int cap, int audit)
1453 {
1454 struct common_audit_data ad;
1455 struct av_decision avd;
1456 u16 sclass;
1457 u32 sid = cred_sid(cred);
1458 u32 av = CAP_TO_MASK(cap);
1459 int rc;
1460
1461 ad.type = LSM_AUDIT_DATA_CAP;
1462 ad.u.cap = cap;
1463
1464 switch (CAP_TO_INDEX(cap)) {
1465 case 0:
1466 sclass = SECCLASS_CAPABILITY;
1467 break;
1468 case 1:
1469 sclass = SECCLASS_CAPABILITY2;
1470 break;
1471 default:
1472 printk(KERN_ERR
1473 "SELinux: out of range capability %d\n", cap);
1474 BUG();
1475 return -EINVAL;
1476 }
1477
1478 rc = avc_has_perm_noaudit(sid, sid, sclass, av, 0, &avd);
1479 if (audit == SECURITY_CAP_AUDIT) {
1480 int rc2 = avc_audit(sid, sid, sclass, av, &avd, rc, &ad, 0);
1481 if (rc2)
1482 return rc2;
1483 }
1484 return rc;
1485 }
1486
1487 /* Check whether a task is allowed to use a system operation. */
1488 static int task_has_system(struct task_struct *tsk,
1489 u32 perms)
1490 {
1491 u32 sid = task_sid(tsk);
1492
1493 return avc_has_perm(sid, SECINITSID_KERNEL,
1494 SECCLASS_SYSTEM, perms, NULL);
1495 }
1496
1497 /* Check whether a task has a particular permission to an inode.
1498 The 'adp' parameter is optional and allows other audit
1499 data to be passed (e.g. the dentry). */
1500 static int inode_has_perm(const struct cred *cred,
1501 struct inode *inode,
1502 u32 perms,
1503 struct common_audit_data *adp,
1504 unsigned flags)
1505 {
1506 struct inode_security_struct *isec;
1507 u32 sid;
1508
1509 validate_creds(cred);
1510
1511 if (unlikely(IS_PRIVATE(inode)))
1512 return 0;
1513
1514 sid = cred_sid(cred);
1515 isec = inode->i_security;
1516
1517 return avc_has_perm_flags(sid, isec->sid, isec->sclass, perms, adp, flags);
1518 }
1519
1520 /* Same as inode_has_perm, but pass explicit audit data containing
1521 the dentry to help the auditing code to more easily generate the
1522 pathname if needed. */
1523 static inline int dentry_has_perm(const struct cred *cred,
1524 struct dentry *dentry,
1525 u32 av)
1526 {
1527 struct inode *inode = dentry->d_inode;
1528 struct common_audit_data ad;
1529
1530 ad.type = LSM_AUDIT_DATA_DENTRY;
1531 ad.u.dentry = dentry;
1532 return inode_has_perm(cred, inode, av, &ad, 0);
1533 }
1534
1535 /* Same as inode_has_perm, but pass explicit audit data containing
1536 the path to help the auditing code to more easily generate the
1537 pathname if needed. */
1538 static inline int path_has_perm(const struct cred *cred,
1539 struct path *path,
1540 u32 av)
1541 {
1542 struct inode *inode = path->dentry->d_inode;
1543 struct common_audit_data ad;
1544
1545 ad.type = LSM_AUDIT_DATA_PATH;
1546 ad.u.path = *path;
1547 return inode_has_perm(cred, inode, av, &ad, 0);
1548 }
1549
1550 /* Same as path_has_perm, but uses the inode from the file struct. */
1551 static inline int file_path_has_perm(const struct cred *cred,
1552 struct file *file,
1553 u32 av)
1554 {
1555 struct common_audit_data ad;
1556
1557 ad.type = LSM_AUDIT_DATA_PATH;
1558 ad.u.path = file->f_path;
1559 return inode_has_perm(cred, file_inode(file), av, &ad, 0);
1560 }
1561
1562 /* Check whether a task can use an open file descriptor to
1563 access an inode in a given way. Check access to the
1564 descriptor itself, and then use dentry_has_perm to
1565 check a particular permission to the file.
1566 Access to the descriptor is implicitly granted if it
1567 has the same SID as the process. If av is zero, then
1568 access to the file is not checked, e.g. for cases
1569 where only the descriptor is affected like seek. */
1570 static int file_has_perm(const struct cred *cred,
1571 struct file *file,
1572 u32 av)
1573 {
1574 struct file_security_struct *fsec = file->f_security;
1575 struct inode *inode = file_inode(file);
1576 struct common_audit_data ad;
1577 u32 sid = cred_sid(cred);
1578 int rc;
1579
1580 ad.type = LSM_AUDIT_DATA_PATH;
1581 ad.u.path = file->f_path;
1582
1583 if (sid != fsec->sid) {
1584 rc = avc_has_perm(sid, fsec->sid,
1585 SECCLASS_FD,
1586 FD__USE,
1587 &ad);
1588 if (rc)
1589 goto out;
1590 }
1591
1592 /* av is zero if only checking access to the descriptor. */
1593 rc = 0;
1594 if (av)
1595 rc = inode_has_perm(cred, inode, av, &ad, 0);
1596
1597 out:
1598 return rc;
1599 }
1600
1601 /* Check whether a task can create a file. */
1602 static int may_create(struct inode *dir,
1603 struct dentry *dentry,
1604 u16 tclass)
1605 {
1606 const struct task_security_struct *tsec = current_security();
1607 struct inode_security_struct *dsec;
1608 struct superblock_security_struct *sbsec;
1609 u32 sid, newsid;
1610 struct common_audit_data ad;
1611 int rc;
1612
1613 dsec = dir->i_security;
1614 sbsec = dir->i_sb->s_security;
1615
1616 sid = tsec->sid;
1617 newsid = tsec->create_sid;
1618
1619 ad.type = LSM_AUDIT_DATA_DENTRY;
1620 ad.u.dentry = dentry;
1621
1622 rc = avc_has_perm(sid, dsec->sid, SECCLASS_DIR,
1623 DIR__ADD_NAME | DIR__SEARCH,
1624 &ad);
1625 if (rc)
1626 return rc;
1627
1628 if (!newsid || !(sbsec->flags & SE_SBLABELSUPP)) {
1629 rc = security_transition_sid(sid, dsec->sid, tclass,
1630 &dentry->d_name, &newsid);
1631 if (rc)
1632 return rc;
1633 }
1634
1635 rc = avc_has_perm(sid, newsid, tclass, FILE__CREATE, &ad);
1636 if (rc)
1637 return rc;
1638
1639 return avc_has_perm(newsid, sbsec->sid,
1640 SECCLASS_FILESYSTEM,
1641 FILESYSTEM__ASSOCIATE, &ad);
1642 }
1643
1644 /* Check whether a task can create a key. */
1645 static int may_create_key(u32 ksid,
1646 struct task_struct *ctx)
1647 {
1648 u32 sid = task_sid(ctx);
1649
1650 return avc_has_perm(sid, ksid, SECCLASS_KEY, KEY__CREATE, NULL);
1651 }
1652
1653 #define MAY_LINK 0
1654 #define MAY_UNLINK 1
1655 #define MAY_RMDIR 2
1656
1657 /* Check whether a task can link, unlink, or rmdir a file/directory. */
1658 static int may_link(struct inode *dir,
1659 struct dentry *dentry,
1660 int kind)
1661
1662 {
1663 struct inode_security_struct *dsec, *isec;
1664 struct common_audit_data ad;
1665 u32 sid = current_sid();
1666 u32 av;
1667 int rc;
1668
1669 dsec = dir->i_security;
1670 isec = dentry->d_inode->i_security;
1671
1672 ad.type = LSM_AUDIT_DATA_DENTRY;
1673 ad.u.dentry = dentry;
1674
1675 av = DIR__SEARCH;
1676 av |= (kind ? DIR__REMOVE_NAME : DIR__ADD_NAME);
1677 rc = avc_has_perm(sid, dsec->sid, SECCLASS_DIR, av, &ad);
1678 if (rc)
1679 return rc;
1680
1681 switch (kind) {
1682 case MAY_LINK:
1683 av = FILE__LINK;
1684 break;
1685 case MAY_UNLINK:
1686 av = FILE__UNLINK;
1687 break;
1688 case MAY_RMDIR:
1689 av = DIR__RMDIR;
1690 break;
1691 default:
1692 printk(KERN_WARNING "SELinux: %s: unrecognized kind %d\n",
1693 __func__, kind);
1694 return 0;
1695 }
1696
1697 rc = avc_has_perm(sid, isec->sid, isec->sclass, av, &ad);
1698 return rc;
1699 }
1700
1701 static inline int may_rename(struct inode *old_dir,
1702 struct dentry *old_dentry,
1703 struct inode *new_dir,
1704 struct dentry *new_dentry)
1705 {
1706 struct inode_security_struct *old_dsec, *new_dsec, *old_isec, *new_isec;
1707 struct common_audit_data ad;
1708 u32 sid = current_sid();
1709 u32 av;
1710 int old_is_dir, new_is_dir;
1711 int rc;
1712
1713 old_dsec = old_dir->i_security;
1714 old_isec = old_dentry->d_inode->i_security;
1715 old_is_dir = S_ISDIR(old_dentry->d_inode->i_mode);
1716 new_dsec = new_dir->i_security;
1717
1718 ad.type = LSM_AUDIT_DATA_DENTRY;
1719
1720 ad.u.dentry = old_dentry;
1721 rc = avc_has_perm(sid, old_dsec->sid, SECCLASS_DIR,
1722 DIR__REMOVE_NAME | DIR__SEARCH, &ad);
1723 if (rc)
1724 return rc;
1725 rc = avc_has_perm(sid, old_isec->sid,
1726 old_isec->sclass, FILE__RENAME, &ad);
1727 if (rc)
1728 return rc;
1729 if (old_is_dir && new_dir != old_dir) {
1730 rc = avc_has_perm(sid, old_isec->sid,
1731 old_isec->sclass, DIR__REPARENT, &ad);
1732 if (rc)
1733 return rc;
1734 }
1735
1736 ad.u.dentry = new_dentry;
1737 av = DIR__ADD_NAME | DIR__SEARCH;
1738 if (new_dentry->d_inode)
1739 av |= DIR__REMOVE_NAME;
1740 rc = avc_has_perm(sid, new_dsec->sid, SECCLASS_DIR, av, &ad);
1741 if (rc)
1742 return rc;
1743 if (new_dentry->d_inode) {
1744 new_isec = new_dentry->d_inode->i_security;
1745 new_is_dir = S_ISDIR(new_dentry->d_inode->i_mode);
1746 rc = avc_has_perm(sid, new_isec->sid,
1747 new_isec->sclass,
1748 (new_is_dir ? DIR__RMDIR : FILE__UNLINK), &ad);
1749 if (rc)
1750 return rc;
1751 }
1752
1753 return 0;
1754 }
1755
1756 /* Check whether a task can perform a filesystem operation. */
1757 static int superblock_has_perm(const struct cred *cred,
1758 struct super_block *sb,
1759 u32 perms,
1760 struct common_audit_data *ad)
1761 {
1762 struct superblock_security_struct *sbsec;
1763 u32 sid = cred_sid(cred);
1764
1765 sbsec = sb->s_security;
1766 return avc_has_perm(sid, sbsec->sid, SECCLASS_FILESYSTEM, perms, ad);
1767 }
1768
1769 /* Convert a Linux mode and permission mask to an access vector. */
1770 static inline u32 file_mask_to_av(int mode, int mask)
1771 {
1772 u32 av = 0;
1773
1774 if (!S_ISDIR(mode)) {
1775 if (mask & MAY_EXEC)
1776 av |= FILE__EXECUTE;
1777 if (mask & MAY_READ)
1778 av |= FILE__READ;
1779
1780 if (mask & MAY_APPEND)
1781 av |= FILE__APPEND;
1782 else if (mask & MAY_WRITE)
1783 av |= FILE__WRITE;
1784
1785 } else {
1786 if (mask & MAY_EXEC)
1787 av |= DIR__SEARCH;
1788 if (mask & MAY_WRITE)
1789 av |= DIR__WRITE;
1790 if (mask & MAY_READ)
1791 av |= DIR__READ;
1792 }
1793
1794 return av;
1795 }
1796
1797 /* Convert a Linux file to an access vector. */
1798 static inline u32 file_to_av(struct file *file)
1799 {
1800 u32 av = 0;
1801
1802 if (file->f_mode & FMODE_READ)
1803 av |= FILE__READ;
1804 if (file->f_mode & FMODE_WRITE) {
1805 if (file->f_flags & O_APPEND)
1806 av |= FILE__APPEND;
1807 else
1808 av |= FILE__WRITE;
1809 }
1810 if (!av) {
1811 /*
1812 * Special file opened with flags 3 for ioctl-only use.
1813 */
1814 av = FILE__IOCTL;
1815 }
1816
1817 return av;
1818 }
1819
1820 /*
1821 * Convert a file to an access vector and include the correct open
1822 * open permission.
1823 */
1824 static inline u32 open_file_to_av(struct file *file)
1825 {
1826 u32 av = file_to_av(file);
1827
1828 if (selinux_policycap_openperm)
1829 av |= FILE__OPEN;
1830
1831 return av;
1832 }
1833
1834 /* Hook functions begin here. */
1835
1836 static int selinux_ptrace_access_check(struct task_struct *child,
1837 unsigned int mode)
1838 {
1839 int rc;
1840
1841 rc = cap_ptrace_access_check(child, mode);
1842 if (rc)
1843 return rc;
1844
1845 if (mode & PTRACE_MODE_READ) {
1846 u32 sid = current_sid();
1847 u32 csid = task_sid(child);
1848 return avc_has_perm(sid, csid, SECCLASS_FILE, FILE__READ, NULL);
1849 }
1850
1851 return current_has_perm(child, PROCESS__PTRACE);
1852 }
1853
1854 static int selinux_ptrace_traceme(struct task_struct *parent)
1855 {
1856 int rc;
1857
1858 rc = cap_ptrace_traceme(parent);
1859 if (rc)
1860 return rc;
1861
1862 return task_has_perm(parent, current, PROCESS__PTRACE);
1863 }
1864
1865 static int selinux_capget(struct task_struct *target, kernel_cap_t *effective,
1866 kernel_cap_t *inheritable, kernel_cap_t *permitted)
1867 {
1868 int error;
1869
1870 error = current_has_perm(target, PROCESS__GETCAP);
1871 if (error)
1872 return error;
1873
1874 return cap_capget(target, effective, inheritable, permitted);
1875 }
1876
1877 static int selinux_capset(struct cred *new, const struct cred *old,
1878 const kernel_cap_t *effective,
1879 const kernel_cap_t *inheritable,
1880 const kernel_cap_t *permitted)
1881 {
1882 int error;
1883
1884 error = cap_capset(new, old,
1885 effective, inheritable, permitted);
1886 if (error)
1887 return error;
1888
1889 return cred_has_perm(old, new, PROCESS__SETCAP);
1890 }
1891
1892 /*
1893 * (This comment used to live with the selinux_task_setuid hook,
1894 * which was removed).
1895 *
1896 * Since setuid only affects the current process, and since the SELinux
1897 * controls are not based on the Linux identity attributes, SELinux does not
1898 * need to control this operation. However, SELinux does control the use of
1899 * the CAP_SETUID and CAP_SETGID capabilities using the capable hook.
1900 */
1901
1902 static int selinux_capable(const struct cred *cred, struct user_namespace *ns,
1903 int cap, int audit)
1904 {
1905 int rc;
1906
1907 rc = cap_capable(cred, ns, cap, audit);
1908 if (rc)
1909 return rc;
1910
1911 return cred_has_capability(cred, cap, audit);
1912 }
1913
1914 static int selinux_quotactl(int cmds, int type, int id, struct super_block *sb)
1915 {
1916 const struct cred *cred = current_cred();
1917 int rc = 0;
1918
1919 if (!sb)
1920 return 0;
1921
1922 switch (cmds) {
1923 case Q_SYNC:
1924 case Q_QUOTAON:
1925 case Q_QUOTAOFF:
1926 case Q_SETINFO:
1927 case Q_SETQUOTA:
1928 rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAMOD, NULL);
1929 break;
1930 case Q_GETFMT:
1931 case Q_GETINFO:
1932 case Q_GETQUOTA:
1933 rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAGET, NULL);
1934 break;
1935 default:
1936 rc = 0; /* let the kernel handle invalid cmds */
1937 break;
1938 }
1939 return rc;
1940 }
1941
1942 static int selinux_quota_on(struct dentry *dentry)
1943 {
1944 const struct cred *cred = current_cred();
1945
1946 return dentry_has_perm(cred, dentry, FILE__QUOTAON);
1947 }
1948
1949 static int selinux_syslog(int type)
1950 {
1951 int rc;
1952
1953 switch (type) {
1954 case SYSLOG_ACTION_READ_ALL: /* Read last kernel messages */
1955 case SYSLOG_ACTION_SIZE_BUFFER: /* Return size of the log buffer */
1956 rc = task_has_system(current, SYSTEM__SYSLOG_READ);
1957 break;
1958 case SYSLOG_ACTION_CONSOLE_OFF: /* Disable logging to console */
1959 case SYSLOG_ACTION_CONSOLE_ON: /* Enable logging to console */
1960 /* Set level of messages printed to console */
1961 case SYSLOG_ACTION_CONSOLE_LEVEL:
1962 rc = task_has_system(current, SYSTEM__SYSLOG_CONSOLE);
1963 break;
1964 case SYSLOG_ACTION_CLOSE: /* Close log */
1965 case SYSLOG_ACTION_OPEN: /* Open log */
1966 case SYSLOG_ACTION_READ: /* Read from log */
1967 case SYSLOG_ACTION_READ_CLEAR: /* Read/clear last kernel messages */
1968 case SYSLOG_ACTION_CLEAR: /* Clear ring buffer */
1969 default:
1970 rc = task_has_system(current, SYSTEM__SYSLOG_MOD);
1971 break;
1972 }
1973 return rc;
1974 }
1975
1976 /*
1977 * Check that a process has enough memory to allocate a new virtual
1978 * mapping. 0 means there is enough memory for the allocation to
1979 * succeed and -ENOMEM implies there is not.
1980 *
1981 * Do not audit the selinux permission check, as this is applied to all
1982 * processes that allocate mappings.
1983 */
1984 static int selinux_vm_enough_memory(struct mm_struct *mm, long pages)
1985 {
1986 int rc, cap_sys_admin = 0;
1987
1988 rc = selinux_capable(current_cred(), &init_user_ns, CAP_SYS_ADMIN,
1989 SECURITY_CAP_NOAUDIT);
1990 if (rc == 0)
1991 cap_sys_admin = 1;
1992
1993 return __vm_enough_memory(mm, pages, cap_sys_admin);
1994 }
1995
1996 /* binprm security operations */
1997
1998 static int selinux_bprm_set_creds(struct linux_binprm *bprm)
1999 {
2000 const struct task_security_struct *old_tsec;
2001 struct task_security_struct *new_tsec;
2002 struct inode_security_struct *isec;
2003 struct common_audit_data ad;
2004 struct inode *inode = file_inode(bprm->file);
2005 int rc;
2006
2007 rc = cap_bprm_set_creds(bprm);
2008 if (rc)
2009 return rc;
2010
2011 /* SELinux context only depends on initial program or script and not
2012 * the script interpreter */
2013 if (bprm->cred_prepared)
2014 return 0;
2015
2016 old_tsec = current_security();
2017 new_tsec = bprm->cred->security;
2018 isec = inode->i_security;
2019
2020 /* Default to the current task SID. */
2021 new_tsec->sid = old_tsec->sid;
2022 new_tsec->osid = old_tsec->sid;
2023
2024 /* Reset fs, key, and sock SIDs on execve. */
2025 new_tsec->create_sid = 0;
2026 new_tsec->keycreate_sid = 0;
2027 new_tsec->sockcreate_sid = 0;
2028
2029 if (old_tsec->exec_sid) {
2030 new_tsec->sid = old_tsec->exec_sid;
2031 /* Reset exec SID on execve. */
2032 new_tsec->exec_sid = 0;
2033
2034 /*
2035 * Minimize confusion: if no_new_privs and a transition is
2036 * explicitly requested, then fail the exec.
2037 */
2038 if (bprm->unsafe & LSM_UNSAFE_NO_NEW_PRIVS)
2039 return -EPERM;
2040 } else {
2041 /* Check for a default transition on this program. */
2042 rc = security_transition_sid(old_tsec->sid, isec->sid,
2043 SECCLASS_PROCESS, NULL,
2044 &new_tsec->sid);
2045 if (rc)
2046 return rc;
2047 }
2048
2049 ad.type = LSM_AUDIT_DATA_PATH;
2050 ad.u.path = bprm->file->f_path;
2051
2052 if ((bprm->file->f_path.mnt->mnt_flags & MNT_NOSUID) ||
2053 (bprm->unsafe & LSM_UNSAFE_NO_NEW_PRIVS))
2054 new_tsec->sid = old_tsec->sid;
2055
2056 if (new_tsec->sid == old_tsec->sid) {
2057 rc = avc_has_perm(old_tsec->sid, isec->sid,
2058 SECCLASS_FILE, FILE__EXECUTE_NO_TRANS, &ad);
2059 if (rc)
2060 return rc;
2061 } else {
2062 /* Check permissions for the transition. */
2063 rc = avc_has_perm(old_tsec->sid, new_tsec->sid,
2064 SECCLASS_PROCESS, PROCESS__TRANSITION, &ad);
2065 if (rc)
2066 return rc;
2067
2068 rc = avc_has_perm(new_tsec->sid, isec->sid,
2069 SECCLASS_FILE, FILE__ENTRYPOINT, &ad);
2070 if (rc)
2071 return rc;
2072
2073 /* Check for shared state */
2074 if (bprm->unsafe & LSM_UNSAFE_SHARE) {
2075 rc = avc_has_perm(old_tsec->sid, new_tsec->sid,
2076 SECCLASS_PROCESS, PROCESS__SHARE,
2077 NULL);
2078 if (rc)
2079 return -EPERM;
2080 }
2081
2082 /* Make sure that anyone attempting to ptrace over a task that
2083 * changes its SID has the appropriate permit */
2084 if (bprm->unsafe &
2085 (LSM_UNSAFE_PTRACE | LSM_UNSAFE_PTRACE_CAP)) {
2086 struct task_struct *tracer;
2087 struct task_security_struct *sec;
2088 u32 ptsid = 0;
2089
2090 rcu_read_lock();
2091 tracer = ptrace_parent(current);
2092 if (likely(tracer != NULL)) {
2093 sec = __task_cred(tracer)->security;
2094 ptsid = sec->sid;
2095 }
2096 rcu_read_unlock();
2097
2098 if (ptsid != 0) {
2099 rc = avc_has_perm(ptsid, new_tsec->sid,
2100 SECCLASS_PROCESS,
2101 PROCESS__PTRACE, NULL);
2102 if (rc)
2103 return -EPERM;
2104 }
2105 }
2106
2107 /* Clear any possibly unsafe personality bits on exec: */
2108 bprm->per_clear |= PER_CLEAR_ON_SETID;
2109 }
2110
2111 return 0;
2112 }
2113
2114 static int selinux_bprm_secureexec(struct linux_binprm *bprm)
2115 {
2116 const struct task_security_struct *tsec = current_security();
2117 u32 sid, osid;
2118 int atsecure = 0;
2119
2120 sid = tsec->sid;
2121 osid = tsec->osid;
2122
2123 if (osid != sid) {
2124 /* Enable secure mode for SIDs transitions unless
2125 the noatsecure permission is granted between
2126 the two SIDs, i.e. ahp returns 0. */
2127 atsecure = avc_has_perm(osid, sid,
2128 SECCLASS_PROCESS,
2129 PROCESS__NOATSECURE, NULL);
2130 }
2131
2132 return (atsecure || cap_bprm_secureexec(bprm));
2133 }
2134
2135 static int match_file(const void *p, struct file *file, unsigned fd)
2136 {
2137 return file_has_perm(p, file, file_to_av(file)) ? fd + 1 : 0;
2138 }
2139
2140 /* Derived from fs/exec.c:flush_old_files. */
2141 static inline void flush_unauthorized_files(const struct cred *cred,
2142 struct files_struct *files)
2143 {
2144 struct file *file, *devnull = NULL;
2145 struct tty_struct *tty;
2146 int drop_tty = 0;
2147 unsigned n;
2148
2149 tty = get_current_tty();
2150 if (tty) {
2151 spin_lock(&tty_files_lock);
2152 if (!list_empty(&tty->tty_files)) {
2153 struct tty_file_private *file_priv;
2154
2155 /* Revalidate access to controlling tty.
2156 Use file_path_has_perm on the tty path directly
2157 rather than using file_has_perm, as this particular
2158 open file may belong to another process and we are
2159 only interested in the inode-based check here. */
2160 file_priv = list_first_entry(&tty->tty_files,
2161 struct tty_file_private, list);
2162 file = file_priv->file;
2163 if (file_path_has_perm(cred, file, FILE__READ | FILE__WRITE))
2164 drop_tty = 1;
2165 }
2166 spin_unlock(&tty_files_lock);
2167 tty_kref_put(tty);
2168 }
2169 /* Reset controlling tty. */
2170 if (drop_tty)
2171 no_tty();
2172
2173 /* Revalidate access to inherited open files. */
2174 n = iterate_fd(files, 0, match_file, cred);
2175 if (!n) /* none found? */
2176 return;
2177
2178 devnull = dentry_open(&selinux_null, O_RDWR, cred);
2179 if (IS_ERR(devnull))
2180 devnull = NULL;
2181 /* replace all the matching ones with this */
2182 do {
2183 replace_fd(n - 1, devnull, 0);
2184 } while ((n = iterate_fd(files, n, match_file, cred)) != 0);
2185 if (devnull)
2186 fput(devnull);
2187 }
2188
2189 /*
2190 * Prepare a process for imminent new credential changes due to exec
2191 */
2192 static void selinux_bprm_committing_creds(struct linux_binprm *bprm)
2193 {
2194 struct task_security_struct *new_tsec;
2195 struct rlimit *rlim, *initrlim;
2196 int rc, i;
2197
2198 new_tsec = bprm->cred->security;
2199 if (new_tsec->sid == new_tsec->osid)
2200 return;
2201
2202 /* Close files for which the new task SID is not authorized. */
2203 flush_unauthorized_files(bprm->cred, current->files);
2204
2205 /* Always clear parent death signal on SID transitions. */
2206 current->pdeath_signal = 0;
2207
2208 /* Check whether the new SID can inherit resource limits from the old
2209 * SID. If not, reset all soft limits to the lower of the current
2210 * task's hard limit and the init task's soft limit.
2211 *
2212 * Note that the setting of hard limits (even to lower them) can be
2213 * controlled by the setrlimit check. The inclusion of the init task's
2214 * soft limit into the computation is to avoid resetting soft limits
2215 * higher than the default soft limit for cases where the default is
2216 * lower than the hard limit, e.g. RLIMIT_CORE or RLIMIT_STACK.
2217 */
2218 rc = avc_has_perm(new_tsec->osid, new_tsec->sid, SECCLASS_PROCESS,
2219 PROCESS__RLIMITINH, NULL);
2220 if (rc) {
2221 /* protect against do_prlimit() */
2222 task_lock(current);
2223 for (i = 0; i < RLIM_NLIMITS; i++) {
2224 rlim = current->signal->rlim + i;
2225 initrlim = init_task.signal->rlim + i;
2226 rlim->rlim_cur = min(rlim->rlim_max, initrlim->rlim_cur);
2227 }
2228 task_unlock(current);
2229 update_rlimit_cpu(current, rlimit(RLIMIT_CPU));
2230 }
2231 }
2232
2233 /*
2234 * Clean up the process immediately after the installation of new credentials
2235 * due to exec
2236 */
2237 static void selinux_bprm_committed_creds(struct linux_binprm *bprm)
2238 {
2239 const struct task_security_struct *tsec = current_security();
2240 struct itimerval itimer;
2241 u32 osid, sid;
2242 int rc, i;
2243
2244 osid = tsec->osid;
2245 sid = tsec->sid;
2246
2247 if (sid == osid)
2248 return;
2249
2250 /* Check whether the new SID can inherit signal state from the old SID.
2251 * If not, clear itimers to avoid subsequent signal generation and
2252 * flush and unblock signals.
2253 *
2254 * This must occur _after_ the task SID has been updated so that any
2255 * kill done after the flush will be checked against the new SID.
2256 */
2257 rc = avc_has_perm(osid, sid, SECCLASS_PROCESS, PROCESS__SIGINH, NULL);
2258 if (rc) {
2259 memset(&itimer, 0, sizeof itimer);
2260 for (i = 0; i < 3; i++)
2261 do_setitimer(i, &itimer, NULL);
2262 spin_lock_irq(&current->sighand->siglock);
2263 if (!(current->signal->flags & SIGNAL_GROUP_EXIT)) {
2264 __flush_signals(current);
2265 flush_signal_handlers(current, 1);
2266 sigemptyset(&current->blocked);
2267 }
2268 spin_unlock_irq(&current->sighand->siglock);
2269 }
2270
2271 /* Wake up the parent if it is waiting so that it can recheck
2272 * wait permission to the new task SID. */
2273 read_lock(&tasklist_lock);
2274 __wake_up_parent(current, current->real_parent);
2275 read_unlock(&tasklist_lock);
2276 }
2277
2278 /* superblock security operations */
2279
2280 static int selinux_sb_alloc_security(struct super_block *sb)
2281 {
2282 return superblock_alloc_security(sb);
2283 }
2284
2285 static void selinux_sb_free_security(struct super_block *sb)
2286 {
2287 superblock_free_security(sb);
2288 }
2289
2290 static inline int match_prefix(char *prefix, int plen, char *option, int olen)
2291 {
2292 if (plen > olen)
2293 return 0;
2294
2295 return !memcmp(prefix, option, plen);
2296 }
2297
2298 static inline int selinux_option(char *option, int len)
2299 {
2300 return (match_prefix(CONTEXT_STR, sizeof(CONTEXT_STR)-1, option, len) ||
2301 match_prefix(FSCONTEXT_STR, sizeof(FSCONTEXT_STR)-1, option, len) ||
2302 match_prefix(DEFCONTEXT_STR, sizeof(DEFCONTEXT_STR)-1, option, len) ||
2303 match_prefix(ROOTCONTEXT_STR, sizeof(ROOTCONTEXT_STR)-1, option, len) ||
2304 match_prefix(LABELSUPP_STR, sizeof(LABELSUPP_STR)-1, option, len));
2305 }
2306
2307 static inline void take_option(char **to, char *from, int *first, int len)
2308 {
2309 if (!*first) {
2310 **to = ',';
2311 *to += 1;
2312 } else
2313 *first = 0;
2314 memcpy(*to, from, len);
2315 *to += len;
2316 }
2317
2318 static inline void take_selinux_option(char **to, char *from, int *first,
2319 int len)
2320 {
2321 int current_size = 0;
2322
2323 if (!*first) {
2324 **to = '|';
2325 *to += 1;
2326 } else
2327 *first = 0;
2328
2329 while (current_size < len) {
2330 if (*from != '"') {
2331 **to = *from;
2332 *to += 1;
2333 }
2334 from += 1;
2335 current_size += 1;
2336 }
2337 }
2338
2339 static int selinux_sb_copy_data(char *orig, char *copy)
2340 {
2341 int fnosec, fsec, rc = 0;
2342 char *in_save, *in_curr, *in_end;
2343 char *sec_curr, *nosec_save, *nosec;
2344 int open_quote = 0;
2345
2346 in_curr = orig;
2347 sec_curr = copy;
2348
2349 nosec = (char *)get_zeroed_page(GFP_KERNEL);
2350 if (!nosec) {
2351 rc = -ENOMEM;
2352 goto out;
2353 }
2354
2355 nosec_save = nosec;
2356 fnosec = fsec = 1;
2357 in_save = in_end = orig;
2358
2359 do {
2360 if (*in_end == '"')
2361 open_quote = !open_quote;
2362 if ((*in_end == ',' && open_quote == 0) ||
2363 *in_end == '\0') {
2364 int len = in_end - in_curr;
2365
2366 if (selinux_option(in_curr, len))
2367 take_selinux_option(&sec_curr, in_curr, &fsec, len);
2368 else
2369 take_option(&nosec, in_curr, &fnosec, len);
2370
2371 in_curr = in_end + 1;
2372 }
2373 } while (*in_end++);
2374
2375 strcpy(in_save, nosec_save);
2376 free_page((unsigned long)nosec_save);
2377 out:
2378 return rc;
2379 }
2380
2381 static int selinux_sb_remount(struct super_block *sb, void *data)
2382 {
2383 int rc, i, *flags;
2384 struct security_mnt_opts opts;
2385 char *secdata, **mount_options;
2386 struct superblock_security_struct *sbsec = sb->s_security;
2387
2388 if (!(sbsec->flags & SE_SBINITIALIZED))
2389 return 0;
2390
2391 if (!data)
2392 return 0;
2393
2394 if (sb->s_type->fs_flags & FS_BINARY_MOUNTDATA)
2395 return 0;
2396
2397 security_init_mnt_opts(&opts);
2398 secdata = alloc_secdata();
2399 if (!secdata)
2400 return -ENOMEM;
2401 rc = selinux_sb_copy_data(data, secdata);
2402 if (rc)
2403 goto out_free_secdata;
2404
2405 rc = selinux_parse_opts_str(secdata, &opts);
2406 if (rc)
2407 goto out_free_secdata;
2408
2409 mount_options = opts.mnt_opts;
2410 flags = opts.mnt_opts_flags;
2411
2412 for (i = 0; i < opts.num_mnt_opts; i++) {
2413 u32 sid;
2414 size_t len;
2415
2416 if (flags[i] == SE_SBLABELSUPP)
2417 continue;
2418 len = strlen(mount_options[i]);
2419 rc = security_context_to_sid(mount_options[i], len, &sid);
2420 if (rc) {
2421 printk(KERN_WARNING "SELinux: security_context_to_sid"
2422 "(%s) failed for (dev %s, type %s) errno=%d\n",
2423 mount_options[i], sb->s_id, sb->s_type->name, rc);
2424 goto out_free_opts;
2425 }
2426 rc = -EINVAL;
2427 switch (flags[i]) {
2428 case FSCONTEXT_MNT:
2429 if (bad_option(sbsec, FSCONTEXT_MNT, sbsec->sid, sid))
2430 goto out_bad_option;
2431 break;
2432 case CONTEXT_MNT:
2433 if (bad_option(sbsec, CONTEXT_MNT, sbsec->mntpoint_sid, sid))
2434 goto out_bad_option;
2435 break;
2436 case ROOTCONTEXT_MNT: {
2437 struct inode_security_struct *root_isec;
2438 root_isec = sb->s_root->d_inode->i_security;
2439
2440 if (bad_option(sbsec, ROOTCONTEXT_MNT, root_isec->sid, sid))
2441 goto out_bad_option;
2442 break;
2443 }
2444 case DEFCONTEXT_MNT:
2445 if (bad_option(sbsec, DEFCONTEXT_MNT, sbsec->def_sid, sid))
2446 goto out_bad_option;
2447 break;
2448 default:
2449 goto out_free_opts;
2450 }
2451 }
2452
2453 rc = 0;
2454 out_free_opts:
2455 security_free_mnt_opts(&opts);
2456 out_free_secdata:
2457 free_secdata(secdata);
2458 return rc;
2459 out_bad_option:
2460 printk(KERN_WARNING "SELinux: unable to change security options "
2461 "during remount (dev %s, type=%s)\n", sb->s_id,
2462 sb->s_type->name);
2463 goto out_free_opts;
2464 }
2465
2466 static int selinux_sb_kern_mount(struct super_block *sb, int flags, void *data)
2467 {
2468 const struct cred *cred = current_cred();
2469 struct common_audit_data ad;
2470 int rc;
2471
2472 rc = superblock_doinit(sb, data);
2473 if (rc)
2474 return rc;
2475
2476 /* Allow all mounts performed by the kernel */
2477 if (flags & MS_KERNMOUNT)
2478 return 0;
2479
2480 ad.type = LSM_AUDIT_DATA_DENTRY;
2481 ad.u.dentry = sb->s_root;
2482 return superblock_has_perm(cred, sb, FILESYSTEM__MOUNT, &ad);
2483 }
2484
2485 static int selinux_sb_statfs(struct dentry *dentry)
2486 {
2487 const struct cred *cred = current_cred();
2488 struct common_audit_data ad;
2489
2490 ad.type = LSM_AUDIT_DATA_DENTRY;
2491 ad.u.dentry = dentry->d_sb->s_root;
2492 return superblock_has_perm(cred, dentry->d_sb, FILESYSTEM__GETATTR, &ad);
2493 }
2494
2495 static int selinux_mount(const char *dev_name,
2496 struct path *path,
2497 const char *type,
2498 unsigned long flags,
2499 void *data)
2500 {
2501 const struct cred *cred = current_cred();
2502
2503 if (flags & MS_REMOUNT)
2504 return superblock_has_perm(cred, path->dentry->d_sb,
2505 FILESYSTEM__REMOUNT, NULL);
2506 else
2507 return path_has_perm(cred, path, FILE__MOUNTON);
2508 }
2509
2510 static int selinux_umount(struct vfsmount *mnt, int flags)
2511 {
2512 const struct cred *cred = current_cred();
2513
2514 return superblock_has_perm(cred, mnt->mnt_sb,
2515 FILESYSTEM__UNMOUNT, NULL);
2516 }
2517
2518 /* inode security operations */
2519
2520 static int selinux_inode_alloc_security(struct inode *inode)
2521 {
2522 return inode_alloc_security(inode);
2523 }
2524
2525 static void selinux_inode_free_security(struct inode *inode)
2526 {
2527 inode_free_security(inode);
2528 }
2529
2530 static int selinux_inode_init_security(struct inode *inode, struct inode *dir,
2531 const struct qstr *qstr, char **name,
2532 void **value, size_t *len)
2533 {
2534 const struct task_security_struct *tsec = current_security();
2535 struct inode_security_struct *dsec;
2536 struct superblock_security_struct *sbsec;
2537 u32 sid, newsid, clen;
2538 int rc;
2539 char *namep = NULL, *context;
2540
2541 dsec = dir->i_security;
2542 sbsec = dir->i_sb->s_security;
2543
2544 sid = tsec->sid;
2545 newsid = tsec->create_sid;
2546
2547 if ((sbsec->flags & SE_SBINITIALIZED) &&
2548 (sbsec->behavior == SECURITY_FS_USE_MNTPOINT))
2549 newsid = sbsec->mntpoint_sid;
2550 else if (!newsid || !(sbsec->flags & SE_SBLABELSUPP)) {
2551 rc = security_transition_sid(sid, dsec->sid,
2552 inode_mode_to_security_class(inode->i_mode),
2553 qstr, &newsid);
2554 if (rc) {
2555 printk(KERN_WARNING "%s: "
2556 "security_transition_sid failed, rc=%d (dev=%s "
2557 "ino=%ld)\n",
2558 __func__,
2559 -rc, inode->i_sb->s_id, inode->i_ino);
2560 return rc;
2561 }
2562 }
2563
2564 /* Possibly defer initialization to selinux_complete_init. */
2565 if (sbsec->flags & SE_SBINITIALIZED) {
2566 struct inode_security_struct *isec = inode->i_security;
2567 isec->sclass = inode_mode_to_security_class(inode->i_mode);
2568 isec->sid = newsid;
2569 isec->initialized = 1;
2570 }
2571
2572 if (!ss_initialized || !(sbsec->flags & SE_SBLABELSUPP))
2573 return -EOPNOTSUPP;
2574
2575 if (name) {
2576 namep = kstrdup(XATTR_SELINUX_SUFFIX, GFP_NOFS);
2577 if (!namep)
2578 return -ENOMEM;
2579 *name = namep;
2580 }
2581
2582 if (value && len) {
2583 rc = security_sid_to_context_force(newsid, &context, &clen);
2584 if (rc) {
2585 kfree(namep);
2586 return rc;
2587 }
2588 *value = context;
2589 *len = clen;
2590 }
2591
2592 return 0;
2593 }
2594
2595 static int selinux_inode_create(struct inode *dir, struct dentry *dentry, umode_t mode)
2596 {
2597 return may_create(dir, dentry, SECCLASS_FILE);
2598 }
2599
2600 static int selinux_inode_link(struct dentry *old_dentry, struct inode *dir, struct dentry *new_dentry)
2601 {
2602 return may_link(dir, old_dentry, MAY_LINK);
2603 }
2604
2605 static int selinux_inode_unlink(struct inode *dir, struct dentry *dentry)
2606 {
2607 return may_link(dir, dentry, MAY_UNLINK);
2608 }
2609
2610 static int selinux_inode_symlink(struct inode *dir, struct dentry *dentry, const char *name)
2611 {
2612 return may_create(dir, dentry, SECCLASS_LNK_FILE);
2613 }
2614
2615 static int selinux_inode_mkdir(struct inode *dir, struct dentry *dentry, umode_t mask)
2616 {
2617 return may_create(dir, dentry, SECCLASS_DIR);
2618 }
2619
2620 static int selinux_inode_rmdir(struct inode *dir, struct dentry *dentry)
2621 {
2622 return may_link(dir, dentry, MAY_RMDIR);
2623 }
2624
2625 static int selinux_inode_mknod(struct inode *dir, struct dentry *dentry, umode_t mode, dev_t dev)
2626 {
2627 return may_create(dir, dentry, inode_mode_to_security_class(mode));
2628 }
2629
2630 static int selinux_inode_rename(struct inode *old_inode, struct dentry *old_dentry,
2631 struct inode *new_inode, struct dentry *new_dentry)
2632 {
2633 return may_rename(old_inode, old_dentry, new_inode, new_dentry);
2634 }
2635
2636 static int selinux_inode_readlink(struct dentry *dentry)
2637 {
2638 const struct cred *cred = current_cred();
2639
2640 return dentry_has_perm(cred, dentry, FILE__READ);
2641 }
2642
2643 static int selinux_inode_follow_link(struct dentry *dentry, struct nameidata *nameidata)
2644 {
2645 const struct cred *cred = current_cred();
2646
2647 return dentry_has_perm(cred, dentry, FILE__READ);
2648 }
2649
2650 static noinline int audit_inode_permission(struct inode *inode,
2651 u32 perms, u32 audited, u32 denied,
2652 unsigned flags)
2653 {
2654 struct common_audit_data ad;
2655 struct inode_security_struct *isec = inode->i_security;
2656 int rc;
2657
2658 ad.type = LSM_AUDIT_DATA_INODE;
2659 ad.u.inode = inode;
2660
2661 rc = slow_avc_audit(current_sid(), isec->sid, isec->sclass, perms,
2662 audited, denied, &ad, flags);
2663 if (rc)
2664 return rc;
2665 return 0;
2666 }
2667
2668 static int selinux_inode_permission(struct inode *inode, int mask)
2669 {
2670 const struct cred *cred = current_cred();
2671 u32 perms;
2672 bool from_access;
2673 unsigned flags = mask & MAY_NOT_BLOCK;
2674 struct inode_security_struct *isec;
2675 u32 sid;
2676 struct av_decision avd;
2677 int rc, rc2;
2678 u32 audited, denied;
2679
2680 from_access = mask & MAY_ACCESS;
2681 mask &= (MAY_READ|MAY_WRITE|MAY_EXEC|MAY_APPEND);
2682
2683 /* No permission to check. Existence test. */
2684 if (!mask)
2685 return 0;
2686
2687 validate_creds(cred);
2688
2689 if (unlikely(IS_PRIVATE(inode)))
2690 return 0;
2691
2692 perms = file_mask_to_av(inode->i_mode, mask);
2693
2694 sid = cred_sid(cred);
2695 isec = inode->i_security;
2696
2697 rc = avc_has_perm_noaudit(sid, isec->sid, isec->sclass, perms, 0, &avd);
2698 audited = avc_audit_required(perms, &avd, rc,
2699 from_access ? FILE__AUDIT_ACCESS : 0,
2700 &denied);
2701 if (likely(!audited))
2702 return rc;
2703
2704 rc2 = audit_inode_permission(inode, perms, audited, denied, flags);
2705 if (rc2)
2706 return rc2;
2707 return rc;
2708 }
2709
2710 static int selinux_inode_setattr(struct dentry *dentry, struct iattr *iattr)
2711 {
2712 const struct cred *cred = current_cred();
2713 unsigned int ia_valid = iattr->ia_valid;
2714 __u32 av = FILE__WRITE;
2715
2716 /* ATTR_FORCE is just used for ATTR_KILL_S[UG]ID. */
2717 if (ia_valid & ATTR_FORCE) {
2718 ia_valid &= ~(ATTR_KILL_SUID | ATTR_KILL_SGID | ATTR_MODE |
2719 ATTR_FORCE);
2720 if (!ia_valid)
2721 return 0;
2722 }
2723
2724 if (ia_valid & (ATTR_MODE | ATTR_UID | ATTR_GID |
2725 ATTR_ATIME_SET | ATTR_MTIME_SET | ATTR_TIMES_SET))
2726 return dentry_has_perm(cred, dentry, FILE__SETATTR);
2727
2728 if (selinux_policycap_openperm && (ia_valid & ATTR_SIZE))
2729 av |= FILE__OPEN;
2730
2731 return dentry_has_perm(cred, dentry, av);
2732 }
2733
2734 static int selinux_inode_getattr(struct vfsmount *mnt, struct dentry *dentry)
2735 {
2736 const struct cred *cred = current_cred();
2737 struct path path;
2738
2739 path.dentry = dentry;
2740 path.mnt = mnt;
2741
2742 return path_has_perm(cred, &path, FILE__GETATTR);
2743 }
2744
2745 static int selinux_inode_setotherxattr(struct dentry *dentry, const char *name)
2746 {
2747 const struct cred *cred = current_cred();
2748
2749 if (!strncmp(name, XATTR_SECURITY_PREFIX,
2750 sizeof XATTR_SECURITY_PREFIX - 1)) {
2751 if (!strcmp(name, XATTR_NAME_CAPS)) {
2752 if (!capable(CAP_SETFCAP))
2753 return -EPERM;
2754 } else if (!capable(CAP_SYS_ADMIN)) {
2755 /* A different attribute in the security namespace.
2756 Restrict to administrator. */
2757 return -EPERM;
2758 }
2759 }
2760
2761 /* Not an attribute we recognize, so just check the
2762 ordinary setattr permission. */
2763 return dentry_has_perm(cred, dentry, FILE__SETATTR);
2764 }
2765
2766 static int selinux_inode_setxattr(struct dentry *dentry, const char *name,
2767 const void *value, size_t size, int flags)
2768 {
2769 struct inode *inode = dentry->d_inode;
2770 struct inode_security_struct *isec = inode->i_security;
2771 struct superblock_security_struct *sbsec;
2772 struct common_audit_data ad;
2773 u32 newsid, sid = current_sid();
2774 int rc = 0;
2775
2776 if (strcmp(name, XATTR_NAME_SELINUX))
2777 return selinux_inode_setotherxattr(dentry, name);
2778
2779 sbsec = inode->i_sb->s_security;
2780 if (!(sbsec->flags & SE_SBLABELSUPP))
2781 return -EOPNOTSUPP;
2782
2783 if (!inode_owner_or_capable(inode))
2784 return -EPERM;
2785
2786 ad.type = LSM_AUDIT_DATA_DENTRY;
2787 ad.u.dentry = dentry;
2788
2789 rc = avc_has_perm(sid, isec->sid, isec->sclass,
2790 FILE__RELABELFROM, &ad);
2791 if (rc)
2792 return rc;
2793
2794 rc = security_context_to_sid(value, size, &newsid);
2795 if (rc == -EINVAL) {
2796 if (!capable(CAP_MAC_ADMIN)) {
2797 struct audit_buffer *ab;
2798 size_t audit_size;
2799 const char *str;
2800
2801 /* We strip a nul only if it is at the end, otherwise the
2802 * context contains a nul and we should audit that */
2803 if (value) {
2804 str = value;
2805 if (str[size - 1] == '\0')
2806 audit_size = size - 1;
2807 else
2808 audit_size = size;
2809 } else {
2810 str = "";
2811 audit_size = 0;
2812 }
2813 ab = audit_log_start(current->audit_context, GFP_ATOMIC, AUDIT_SELINUX_ERR);
2814 audit_log_format(ab, "op=setxattr invalid_context=");
2815 audit_log_n_untrustedstring(ab, value, audit_size);
2816 audit_log_end(ab);
2817
2818 return rc;
2819 }
2820 rc = security_context_to_sid_force(value, size, &newsid);
2821 }
2822 if (rc)
2823 return rc;
2824
2825 rc = avc_has_perm(sid, newsid, isec->sclass,
2826 FILE__RELABELTO, &ad);
2827 if (rc)
2828 return rc;
2829
2830 rc = security_validate_transition(isec->sid, newsid, sid,
2831 isec->sclass);
2832 if (rc)
2833 return rc;
2834
2835 return avc_has_perm(newsid,
2836 sbsec->sid,
2837 SECCLASS_FILESYSTEM,
2838 FILESYSTEM__ASSOCIATE,
2839 &ad);
2840 }
2841
2842 static void selinux_inode_post_setxattr(struct dentry *dentry, const char *name,
2843 const void *value, size_t size,
2844 int flags)
2845 {
2846 struct inode *inode = dentry->d_inode;
2847 struct inode_security_struct *isec = inode->i_security;
2848 u32 newsid;
2849 int rc;
2850
2851 if (strcmp(name, XATTR_NAME_SELINUX)) {
2852 /* Not an attribute we recognize, so nothing to do. */
2853 return;
2854 }
2855
2856 rc = security_context_to_sid_force(value, size, &newsid);
2857 if (rc) {
2858 printk(KERN_ERR "SELinux: unable to map context to SID"
2859 "for (%s, %lu), rc=%d\n",
2860 inode->i_sb->s_id, inode->i_ino, -rc);
2861 return;
2862 }
2863
2864 isec->sid = newsid;
2865 return;
2866 }
2867
2868 static int selinux_inode_getxattr(struct dentry *dentry, const char *name)
2869 {
2870 const struct cred *cred = current_cred();
2871
2872 return dentry_has_perm(cred, dentry, FILE__GETATTR);
2873 }
2874
2875 static int selinux_inode_listxattr(struct dentry *dentry)
2876 {
2877 const struct cred *cred = current_cred();
2878
2879 return dentry_has_perm(cred, dentry, FILE__GETATTR);
2880 }
2881
2882 static int selinux_inode_removexattr(struct dentry *dentry, const char *name)
2883 {
2884 if (strcmp(name, XATTR_NAME_SELINUX))
2885 return selinux_inode_setotherxattr(dentry, name);
2886
2887 /* No one is allowed to remove a SELinux security label.
2888 You can change the label, but all data must be labeled. */
2889 return -EACCES;
2890 }
2891
2892 /*
2893 * Copy the inode security context value to the user.
2894 *
2895 * Permission check is handled by selinux_inode_getxattr hook.
2896 */
2897 static int selinux_inode_getsecurity(const struct inode *inode, const char *name, void **buffer, bool alloc)
2898 {
2899 u32 size;
2900 int error;
2901 char *context = NULL;
2902 struct inode_security_struct *isec = inode->i_security;
2903
2904 if (strcmp(name, XATTR_SELINUX_SUFFIX))
2905 return -EOPNOTSUPP;
2906
2907 /*
2908 * If the caller has CAP_MAC_ADMIN, then get the raw context
2909 * value even if it is not defined by current policy; otherwise,
2910 * use the in-core value under current policy.
2911 * Use the non-auditing forms of the permission checks since
2912 * getxattr may be called by unprivileged processes commonly
2913 * and lack of permission just means that we fall back to the
2914 * in-core context value, not a denial.
2915 */
2916 error = selinux_capable(current_cred(), &init_user_ns, CAP_MAC_ADMIN,
2917 SECURITY_CAP_NOAUDIT);
2918 if (!error)
2919 error = security_sid_to_context_force(isec->sid, &context,
2920 &size);
2921 else
2922 error = security_sid_to_context(isec->sid, &context, &size);
2923 if (error)
2924 return error;
2925 error = size;
2926 if (alloc) {
2927 *buffer = context;
2928 goto out_nofree;
2929 }
2930 kfree(context);
2931 out_nofree:
2932 return error;
2933 }
2934
2935 static int selinux_inode_setsecurity(struct inode *inode, const char *name,
2936 const void *value, size_t size, int flags)
2937 {
2938 struct inode_security_struct *isec = inode->i_security;
2939 u32 newsid;
2940 int rc;
2941
2942 if (strcmp(name, XATTR_SELINUX_SUFFIX))
2943 return -EOPNOTSUPP;
2944
2945 if (!value || !size)
2946 return -EACCES;
2947
2948 rc = security_context_to_sid((void *)value, size, &newsid);
2949 if (rc)
2950 return rc;
2951
2952 isec->sid = newsid;
2953 isec->initialized = 1;
2954 return 0;
2955 }
2956
2957 static int selinux_inode_listsecurity(struct inode *inode, char *buffer, size_t buffer_size)
2958 {
2959 const int len = sizeof(XATTR_NAME_SELINUX);
2960 if (buffer && len <= buffer_size)
2961 memcpy(buffer, XATTR_NAME_SELINUX, len);
2962 return len;
2963 }
2964
2965 static void selinux_inode_getsecid(const struct inode *inode, u32 *secid)
2966 {
2967 struct inode_security_struct *isec = inode->i_security;
2968 *secid = isec->sid;
2969 }
2970
2971 /* file security operations */
2972
2973 static int selinux_revalidate_file_permission(struct file *file, int mask)
2974 {
2975 const struct cred *cred = current_cred();
2976 struct inode *inode = file_inode(file);
2977
2978 /* file_mask_to_av won't add FILE__WRITE if MAY_APPEND is set */
2979 if ((file->f_flags & O_APPEND) && (mask & MAY_WRITE))
2980 mask |= MAY_APPEND;
2981
2982 return file_has_perm(cred, file,
2983 file_mask_to_av(inode->i_mode, mask));
2984 }
2985
2986 static int selinux_file_permission(struct file *file, int mask)
2987 {
2988 struct inode *inode = file_inode(file);
2989 struct file_security_struct *fsec = file->f_security;
2990 struct inode_security_struct *isec = inode->i_security;
2991 u32 sid = current_sid();
2992
2993 if (!mask)
2994 /* No permission to check. Existence test. */
2995 return 0;
2996
2997 if (sid == fsec->sid && fsec->isid == isec->sid &&
2998 fsec->pseqno == avc_policy_seqno())
2999 /* No change since file_open check. */
3000 return 0;
3001
3002 return selinux_revalidate_file_permission(file, mask);
3003 }
3004
3005 static int selinux_file_alloc_security(struct file *file)
3006 {
3007 return file_alloc_security(file);
3008 }
3009
3010 static void selinux_file_free_security(struct file *file)
3011 {
3012 file_free_security(file);
3013 }
3014
3015 static int selinux_file_ioctl(struct file *file, unsigned int cmd,
3016 unsigned long arg)
3017 {
3018 const struct cred *cred = current_cred();
3019 int error = 0;
3020
3021 switch (cmd) {
3022 case FIONREAD:
3023 /* fall through */
3024 case FIBMAP:
3025 /* fall through */
3026 case FIGETBSZ:
3027 /* fall through */
3028 case FS_IOC_GETFLAGS:
3029 /* fall through */
3030 case FS_IOC_GETVERSION:
3031 error = file_has_perm(cred, file, FILE__GETATTR);
3032 break;
3033
3034 case FS_IOC_SETFLAGS:
3035 /* fall through */
3036 case FS_IOC_SETVERSION:
3037 error = file_has_perm(cred, file, FILE__SETATTR);
3038 break;
3039
3040 /* sys_ioctl() checks */
3041 case FIONBIO:
3042 /* fall through */
3043 case FIOASYNC:
3044 error = file_has_perm(cred, file, 0);
3045 break;
3046
3047 case KDSKBENT:
3048 case KDSKBSENT:
3049 error = cred_has_capability(cred, CAP_SYS_TTY_CONFIG,
3050 SECURITY_CAP_AUDIT);
3051 break;
3052
3053 /* default case assumes that the command will go
3054 * to the file's ioctl() function.
3055 */
3056 default:
3057 error = file_has_perm(cred, file, FILE__IOCTL);
3058 }
3059 return error;
3060 }
3061
3062 static int default_noexec;
3063
3064 static int file_map_prot_check(struct file *file, unsigned long prot, int shared)
3065 {
3066 const struct cred *cred = current_cred();
3067 int rc = 0;
3068
3069 if (default_noexec &&
3070 (prot & PROT_EXEC) && (!file || (!shared && (prot & PROT_WRITE)))) {
3071 /*
3072 * We are making executable an anonymous mapping or a
3073 * private file mapping that will also be writable.
3074 * This has an additional check.
3075 */
3076 rc = cred_has_perm(cred, cred, PROCESS__EXECMEM);
3077 if (rc)
3078 goto error;
3079 }
3080
3081 if (file) {
3082 /* read access is always possible with a mapping */
3083 u32 av = FILE__READ;
3084
3085 /* write access only matters if the mapping is shared */
3086 if (shared && (prot & PROT_WRITE))
3087 av |= FILE__WRITE;
3088
3089 if (prot & PROT_EXEC)
3090 av |= FILE__EXECUTE;
3091
3092 return file_has_perm(cred, file, av);
3093 }
3094
3095 error:
3096 return rc;
3097 }
3098
3099 static int selinux_mmap_addr(unsigned long addr)
3100 {
3101 int rc = 0;
3102 u32 sid = current_sid();
3103
3104 /*
3105 * notice that we are intentionally putting the SELinux check before
3106 * the secondary cap_file_mmap check. This is such a likely attempt
3107 * at bad behaviour/exploit that we always want to get the AVC, even
3108 * if DAC would have also denied the operation.
3109 */
3110 if (addr < CONFIG_LSM_MMAP_MIN_ADDR) {
3111 rc = avc_has_perm(sid, sid, SECCLASS_MEMPROTECT,
3112 MEMPROTECT__MMAP_ZERO, NULL);
3113 if (rc)
3114 return rc;
3115 }
3116
3117 /* do DAC check on address space usage */
3118 return cap_mmap_addr(addr);
3119 }
3120
3121 static int selinux_mmap_file(struct file *file, unsigned long reqprot,
3122 unsigned long prot, unsigned long flags)
3123 {
3124 if (selinux_checkreqprot)
3125 prot = reqprot;
3126
3127 return file_map_prot_check(file, prot,
3128 (flags & MAP_TYPE) == MAP_SHARED);
3129 }
3130
3131 static int selinux_file_mprotect(struct vm_area_struct *vma,
3132 unsigned long reqprot,
3133 unsigned long prot)
3134 {
3135 const struct cred *cred = current_cred();
3136
3137 if (selinux_checkreqprot)
3138 prot = reqprot;
3139
3140 if (default_noexec &&
3141 (prot & PROT_EXEC) && !(vma->vm_flags & VM_EXEC)) {
3142 int rc = 0;
3143 if (vma->vm_start >= vma->vm_mm->start_brk &&
3144 vma->vm_end <= vma->vm_mm->brk) {
3145 rc = cred_has_perm(cred, cred, PROCESS__EXECHEAP);
3146 } else if (!vma->vm_file &&
3147 vma->vm_start <= vma->vm_mm->start_stack &&
3148 vma->vm_end >= vma->vm_mm->start_stack) {
3149 rc = current_has_perm(current, PROCESS__EXECSTACK);
3150 } else if (vma->vm_file && vma->anon_vma) {
3151 /*
3152 * We are making executable a file mapping that has
3153 * had some COW done. Since pages might have been
3154 * written, check ability to execute the possibly
3155 * modified content. This typically should only
3156 * occur for text relocations.
3157 */
3158 rc = file_has_perm(cred, vma->vm_file, FILE__EXECMOD);
3159 }
3160 if (rc)
3161 return rc;
3162 }
3163
3164 return file_map_prot_check(vma->vm_file, prot, vma->vm_flags&VM_SHARED);
3165 }
3166
3167 static int selinux_file_lock(struct file *file, unsigned int cmd)
3168 {
3169 const struct cred *cred = current_cred();
3170
3171 return file_has_perm(cred, file, FILE__LOCK);
3172 }
3173
3174 static int selinux_file_fcntl(struct file *file, unsigned int cmd,
3175 unsigned long arg)
3176 {
3177 const struct cred *cred = current_cred();
3178 int err = 0;
3179
3180 switch (cmd) {
3181 case F_SETFL:
3182 if ((file->f_flags & O_APPEND) && !(arg & O_APPEND)) {
3183 err = file_has_perm(cred, file, FILE__WRITE);
3184 break;
3185 }
3186 /* fall through */
3187 case F_SETOWN:
3188 case F_SETSIG:
3189 case F_GETFL:
3190 case F_GETOWN:
3191 case F_GETSIG:
3192 case F_GETOWNER_UIDS:
3193 /* Just check FD__USE permission */
3194 err = file_has_perm(cred, file, 0);
3195 break;
3196 case F_GETLK:
3197 case F_SETLK:
3198 case F_SETLKW:
3199 #if BITS_PER_LONG == 32
3200 case F_GETLK64:
3201 case F_SETLK64:
3202 case F_SETLKW64:
3203 #endif
3204 err = file_has_perm(cred, file, FILE__LOCK);
3205 break;
3206 }
3207
3208 return err;
3209 }
3210
3211 static int selinux_file_set_fowner(struct file *file)
3212 {
3213 struct file_security_struct *fsec;
3214
3215 fsec = file->f_security;
3216 fsec->fown_sid = current_sid();
3217
3218 return 0;
3219 }
3220
3221 static int selinux_file_send_sigiotask(struct task_struct *tsk,
3222 struct fown_struct *fown, int signum)
3223 {
3224 struct file *file;
3225 u32 sid = task_sid(tsk);
3226 u32 perm;
3227 struct file_security_struct *fsec;
3228
3229 /* struct fown_struct is never outside the context of a struct file */
3230 file = container_of(fown, struct file, f_owner);
3231
3232 fsec = file->f_security;
3233
3234 if (!signum)
3235 perm = signal_to_av(SIGIO); /* as per send_sigio_to_task */
3236 else
3237 perm = signal_to_av(signum);
3238
3239 return avc_has_perm(fsec->fown_sid, sid,
3240 SECCLASS_PROCESS, perm, NULL);
3241 }
3242
3243 static int selinux_file_receive(struct file *file)
3244 {
3245 const struct cred *cred = current_cred();
3246
3247 return file_has_perm(cred, file, file_to_av(file));
3248 }
3249
3250 static int selinux_file_open(struct file *file, const struct cred *cred)
3251 {
3252 struct file_security_struct *fsec;
3253 struct inode_security_struct *isec;
3254
3255 fsec = file->f_security;
3256 isec = file_inode(file)->i_security;
3257 /*
3258 * Save inode label and policy sequence number
3259 * at open-time so that selinux_file_permission
3260 * can determine whether revalidation is necessary.
3261 * Task label is already saved in the file security
3262 * struct as its SID.
3263 */
3264 fsec->isid = isec->sid;
3265 fsec->pseqno = avc_policy_seqno();
3266 /*
3267 * Since the inode label or policy seqno may have changed
3268 * between the selinux_inode_permission check and the saving
3269 * of state above, recheck that access is still permitted.
3270 * Otherwise, access might never be revalidated against the
3271 * new inode label or new policy.
3272 * This check is not redundant - do not remove.
3273 */
3274 return file_path_has_perm(cred, file, open_file_to_av(file));
3275 }
3276
3277 /* task security operations */
3278
3279 static int selinux_task_create(unsigned long clone_flags)
3280 {
3281 return current_has_perm(current, PROCESS__FORK);
3282 }
3283
3284 /*
3285 * allocate the SELinux part of blank credentials
3286 */
3287 static int selinux_cred_alloc_blank(struct cred *cred, gfp_t gfp)
3288 {
3289 struct task_security_struct *tsec;
3290
3291 tsec = kzalloc(sizeof(struct task_security_struct), gfp);
3292 if (!tsec)
3293 return -ENOMEM;
3294
3295 cred->security = tsec;
3296 return 0;
3297 }
3298
3299 /*
3300 * detach and free the LSM part of a set of credentials
3301 */
3302 static void selinux_cred_free(struct cred *cred)
3303 {
3304 struct task_security_struct *tsec = cred->security;
3305
3306 /*
3307 * cred->security == NULL if security_cred_alloc_blank() or
3308 * security_prepare_creds() returned an error.
3309 */
3310 BUG_ON(cred->security && (unsigned long) cred->security < PAGE_SIZE);
3311 cred->security = (void *) 0x7UL;
3312 kfree(tsec);
3313 }
3314
3315 /*
3316 * prepare a new set of credentials for modification
3317 */
3318 static int selinux_cred_prepare(struct cred *new, const struct cred *old,
3319 gfp_t gfp)
3320 {
3321 const struct task_security_struct *old_tsec;
3322 struct task_security_struct *tsec;
3323
3324 old_tsec = old->security;
3325
3326 tsec = kmemdup(old_tsec, sizeof(struct task_security_struct), gfp);
3327 if (!tsec)
3328 return -ENOMEM;
3329
3330 new->security = tsec;
3331 return 0;
3332 }
3333
3334 /*
3335 * transfer the SELinux data to a blank set of creds
3336 */
3337 static void selinux_cred_transfer(struct cred *new, const struct cred *old)
3338 {
3339 const struct task_security_struct *old_tsec = old->security;
3340 struct task_security_struct *tsec = new->security;
3341
3342 *tsec = *old_tsec;
3343 }
3344
3345 /*
3346 * set the security data for a kernel service
3347 * - all the creation contexts are set to unlabelled
3348 */
3349 static int selinux_kernel_act_as(struct cred *new, u32 secid)
3350 {
3351 struct task_security_struct *tsec = new->security;
3352 u32 sid = current_sid();
3353 int ret;
3354
3355 ret = avc_has_perm(sid, secid,
3356 SECCLASS_KERNEL_SERVICE,
3357 KERNEL_SERVICE__USE_AS_OVERRIDE,
3358 NULL);
3359 if (ret == 0) {
3360 tsec->sid = secid;
3361 tsec->create_sid = 0;
3362 tsec->keycreate_sid = 0;
3363 tsec->sockcreate_sid = 0;
3364 }
3365 return ret;
3366 }
3367
3368 /*
3369 * set the file creation context in a security record to the same as the
3370 * objective context of the specified inode
3371 */
3372 static int selinux_kernel_create_files_as(struct cred *new, struct inode *inode)
3373 {
3374 struct inode_security_struct *isec = inode->i_security;
3375 struct task_security_struct *tsec = new->security;
3376 u32 sid = current_sid();
3377 int ret;
3378
3379 ret = avc_has_perm(sid, isec->sid,
3380 SECCLASS_KERNEL_SERVICE,
3381 KERNEL_SERVICE__CREATE_FILES_AS,
3382 NULL);
3383
3384 if (ret == 0)
3385 tsec->create_sid = isec->sid;
3386 return ret;
3387 }
3388
3389 static int selinux_kernel_module_request(char *kmod_name)
3390 {
3391 u32 sid;
3392 struct common_audit_data ad;
3393
3394 sid = task_sid(current);
3395
3396 ad.type = LSM_AUDIT_DATA_KMOD;
3397 ad.u.kmod_name = kmod_name;
3398
3399 return avc_has_perm(sid, SECINITSID_KERNEL, SECCLASS_SYSTEM,
3400 SYSTEM__MODULE_REQUEST, &ad);
3401 }
3402
3403 static int selinux_task_setpgid(struct task_struct *p, pid_t pgid)
3404 {
3405 return current_has_perm(p, PROCESS__SETPGID);
3406 }
3407
3408 static int selinux_task_getpgid(struct task_struct *p)
3409 {
3410 return current_has_perm(p, PROCESS__GETPGID);
3411 }
3412
3413 static int selinux_task_getsid(struct task_struct *p)
3414 {
3415 return current_has_perm(p, PROCESS__GETSESSION);
3416 }
3417
3418 static void selinux_task_getsecid(struct task_struct *p, u32 *secid)
3419 {
3420 *secid = task_sid(p);
3421 }
3422
3423 static int selinux_task_setnice(struct task_struct *p, int nice)
3424 {
3425 int rc;
3426
3427 rc = cap_task_setnice(p, nice);
3428 if (rc)
3429 return rc;
3430
3431 return current_has_perm(p, PROCESS__SETSCHED);
3432 }
3433
3434 static int selinux_task_setioprio(struct task_struct *p, int ioprio)
3435 {
3436 int rc;
3437
3438 rc = cap_task_setioprio(p, ioprio);
3439 if (rc)
3440 return rc;
3441
3442 return current_has_perm(p, PROCESS__SETSCHED);
3443 }
3444
3445 static int selinux_task_getioprio(struct task_struct *p)
3446 {
3447 return current_has_perm(p, PROCESS__GETSCHED);
3448 }
3449
3450 static int selinux_task_setrlimit(struct task_struct *p, unsigned int resource,
3451 struct rlimit *new_rlim)
3452 {
3453 struct rlimit *old_rlim = p->signal->rlim + resource;
3454
3455 /* Control the ability to change the hard limit (whether
3456 lowering or raising it), so that the hard limit can
3457 later be used as a safe reset point for the soft limit
3458 upon context transitions. See selinux_bprm_committing_creds. */
3459 if (old_rlim->rlim_max != new_rlim->rlim_max)
3460 return current_has_perm(p, PROCESS__SETRLIMIT);
3461
3462 return 0;
3463 }
3464
3465 static int selinux_task_setscheduler(struct task_struct *p)
3466 {
3467 int rc;
3468
3469 rc = cap_task_setscheduler(p);
3470 if (rc)
3471 return rc;
3472
3473 return current_has_perm(p, PROCESS__SETSCHED);
3474 }
3475
3476 static int selinux_task_getscheduler(struct task_struct *p)
3477 {
3478 return current_has_perm(p, PROCESS__GETSCHED);
3479 }
3480
3481 static int selinux_task_movememory(struct task_struct *p)
3482 {
3483 return current_has_perm(p, PROCESS__SETSCHED);
3484 }
3485
3486 static int selinux_task_kill(struct task_struct *p, struct siginfo *info,
3487 int sig, u32 secid)
3488 {
3489 u32 perm;
3490 int rc;
3491
3492 if (!sig)
3493 perm = PROCESS__SIGNULL; /* null signal; existence test */
3494 else
3495 perm = signal_to_av(sig);
3496 if (secid)
3497 rc = avc_has_perm(secid, task_sid(p),
3498 SECCLASS_PROCESS, perm, NULL);
3499 else
3500 rc = current_has_perm(p, perm);
3501 return rc;
3502 }
3503
3504 static int selinux_task_wait(struct task_struct *p)
3505 {
3506 return task_has_perm(p, current, PROCESS__SIGCHLD);
3507 }
3508
3509 static void selinux_task_to_inode(struct task_struct *p,
3510 struct inode *inode)
3511 {
3512 struct inode_security_struct *isec = inode->i_security;
3513 u32 sid = task_sid(p);
3514
3515 isec->sid = sid;
3516 isec->initialized = 1;
3517 }
3518
3519 /* Returns error only if unable to parse addresses */
3520 static int selinux_parse_skb_ipv4(struct sk_buff *skb,
3521 struct common_audit_data *ad, u8 *proto)
3522 {
3523 int offset, ihlen, ret = -EINVAL;
3524 struct iphdr _iph, *ih;
3525
3526 offset = skb_network_offset(skb);
3527 ih = skb_header_pointer(skb, offset, sizeof(_iph), &_iph);
3528 if (ih == NULL)
3529 goto out;
3530
3531 ihlen = ih->ihl * 4;
3532 if (ihlen < sizeof(_iph))
3533 goto out;
3534
3535 ad->u.net->v4info.saddr = ih->saddr;
3536 ad->u.net->v4info.daddr = ih->daddr;
3537 ret = 0;
3538
3539 if (proto)
3540 *proto = ih->protocol;
3541
3542 switch (ih->protocol) {
3543 case IPPROTO_TCP: {
3544 struct tcphdr _tcph, *th;
3545
3546 if (ntohs(ih->frag_off) & IP_OFFSET)
3547 break;
3548
3549 offset += ihlen;
3550 th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph);
3551 if (th == NULL)
3552 break;
3553
3554 ad->u.net->sport = th->source;
3555 ad->u.net->dport = th->dest;
3556 break;
3557 }
3558
3559 case IPPROTO_UDP: {
3560 struct udphdr _udph, *uh;
3561
3562 if (ntohs(ih->frag_off) & IP_OFFSET)
3563 break;
3564
3565 offset += ihlen;
3566 uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph);
3567 if (uh == NULL)
3568 break;
3569
3570 ad->u.net->sport = uh->source;
3571 ad->u.net->dport = uh->dest;
3572 break;
3573 }
3574
3575 case IPPROTO_DCCP: {
3576 struct dccp_hdr _dccph, *dh;
3577
3578 if (ntohs(ih->frag_off) & IP_OFFSET)
3579 break;
3580
3581 offset += ihlen;
3582 dh = skb_header_pointer(skb, offset, sizeof(_dccph), &_dccph);
3583 if (dh == NULL)
3584 break;
3585
3586 ad->u.net->sport = dh->dccph_sport;
3587 ad->u.net->dport = dh->dccph_dport;
3588 break;
3589 }
3590
3591 default:
3592 break;
3593 }
3594 out:
3595 return ret;
3596 }
3597
3598 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
3599
3600 /* Returns error only if unable to parse addresses */
3601 static int selinux_parse_skb_ipv6(struct sk_buff *skb,
3602 struct common_audit_data *ad, u8 *proto)
3603 {
3604 u8 nexthdr;
3605 int ret = -EINVAL, offset;
3606 struct ipv6hdr _ipv6h, *ip6;
3607 __be16 frag_off;
3608
3609 offset = skb_network_offset(skb);
3610 ip6 = skb_header_pointer(skb, offset, sizeof(_ipv6h), &_ipv6h);
3611 if (ip6 == NULL)
3612 goto out;
3613
3614 ad->u.net->v6info.saddr = ip6->saddr;
3615 ad->u.net->v6info.daddr = ip6->daddr;
3616 ret = 0;
3617
3618 nexthdr = ip6->nexthdr;
3619 offset += sizeof(_ipv6h);
3620 offset = ipv6_skip_exthdr(skb, offset, &nexthdr, &frag_off);
3621 if (offset < 0)
3622 goto out;
3623
3624 if (proto)
3625 *proto = nexthdr;
3626
3627 switch (nexthdr) {
3628 case IPPROTO_TCP: {
3629 struct tcphdr _tcph, *th;
3630
3631 th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph);
3632 if (th == NULL)
3633 break;
3634
3635 ad->u.net->sport = th->source;
3636 ad->u.net->dport = th->dest;
3637 break;
3638 }
3639
3640 case IPPROTO_UDP: {
3641 struct udphdr _udph, *uh;
3642
3643 uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph);
3644 if (uh == NULL)
3645 break;
3646
3647 ad->u.net->sport = uh->source;
3648 ad->u.net->dport = uh->dest;
3649 break;
3650 }
3651
3652 case IPPROTO_DCCP: {
3653 struct dccp_hdr _dccph, *dh;
3654
3655 dh = skb_header_pointer(skb, offset, sizeof(_dccph), &_dccph);
3656 if (dh == NULL)
3657 break;
3658
3659 ad->u.net->sport = dh->dccph_sport;
3660 ad->u.net->dport = dh->dccph_dport;
3661 break;
3662 }
3663
3664 /* includes fragments */
3665 default:
3666 break;
3667 }
3668 out:
3669 return ret;
3670 }
3671
3672 #endif /* IPV6 */
3673
3674 static int selinux_parse_skb(struct sk_buff *skb, struct common_audit_data *ad,
3675 char **_addrp, int src, u8 *proto)
3676 {
3677 char *addrp;
3678 int ret;
3679
3680 switch (ad->u.net->family) {
3681 case PF_INET:
3682 ret = selinux_parse_skb_ipv4(skb, ad, proto);
3683 if (ret)
3684 goto parse_error;
3685 addrp = (char *)(src ? &ad->u.net->v4info.saddr :
3686 &ad->u.net->v4info.daddr);
3687 goto okay;
3688
3689 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
3690 case PF_INET6:
3691 ret = selinux_parse_skb_ipv6(skb, ad, proto);
3692 if (ret)
3693 goto parse_error;
3694 addrp = (char *)(src ? &ad->u.net->v6info.saddr :
3695 &ad->u.net->v6info.daddr);
3696 goto okay;
3697 #endif /* IPV6 */
3698 default:
3699 addrp = NULL;
3700 goto okay;
3701 }
3702
3703 parse_error:
3704 printk(KERN_WARNING
3705 "SELinux: failure in selinux_parse_skb(),"
3706 " unable to parse packet\n");
3707 return ret;
3708
3709 okay:
3710 if (_addrp)
3711 *_addrp = addrp;
3712 return 0;
3713 }
3714
3715 /**
3716 * selinux_skb_peerlbl_sid - Determine the peer label of a packet
3717 * @skb: the packet
3718 * @family: protocol family
3719 * @sid: the packet's peer label SID
3720 *
3721 * Description:
3722 * Check the various different forms of network peer labeling and determine
3723 * the peer label/SID for the packet; most of the magic actually occurs in
3724 * the security server function security_net_peersid_cmp(). The function
3725 * returns zero if the value in @sid is valid (although it may be SECSID_NULL)
3726 * or -EACCES if @sid is invalid due to inconsistencies with the different
3727 * peer labels.
3728 *
3729 */
3730 static int selinux_skb_peerlbl_sid(struct sk_buff *skb, u16 family, u32 *sid)
3731 {
3732 int err;
3733 u32 xfrm_sid;
3734 u32 nlbl_sid;
3735 u32 nlbl_type;
3736
3737 selinux_skb_xfrm_sid(skb, &xfrm_sid);
3738 selinux_netlbl_skbuff_getsid(skb, family, &nlbl_type, &nlbl_sid);
3739
3740 err = security_net_peersid_resolve(nlbl_sid, nlbl_type, xfrm_sid, sid);
3741 if (unlikely(err)) {
3742 printk(KERN_WARNING
3743 "SELinux: failure in selinux_skb_peerlbl_sid(),"
3744 " unable to determine packet's peer label\n");
3745 return -EACCES;
3746 }
3747
3748 return 0;
3749 }
3750
3751 /* socket security operations */
3752
3753 static int socket_sockcreate_sid(const struct task_security_struct *tsec,
3754 u16 secclass, u32 *socksid)
3755 {
3756 if (tsec->sockcreate_sid > SECSID_NULL) {
3757 *socksid = tsec->sockcreate_sid;
3758 return 0;
3759 }
3760
3761 return security_transition_sid(tsec->sid, tsec->sid, secclass, NULL,
3762 socksid);
3763 }
3764
3765 static int sock_has_perm(struct task_struct *task, struct sock *sk, u32 perms)
3766 {
3767 struct sk_security_struct *sksec = sk->sk_security;
3768 struct common_audit_data ad;
3769 struct lsm_network_audit net = {0,};
3770 u32 tsid = task_sid(task);
3771
3772 if (sksec->sid == SECINITSID_KERNEL)
3773 return 0;
3774
3775 ad.type = LSM_AUDIT_DATA_NET;
3776 ad.u.net = &net;
3777 ad.u.net->sk = sk;
3778
3779 return avc_has_perm(tsid, sksec->sid, sksec->sclass, perms, &ad);
3780 }
3781
3782 static int selinux_socket_create(int family, int type,
3783 int protocol, int kern)
3784 {
3785 const struct task_security_struct *tsec = current_security();
3786 u32 newsid;
3787 u16 secclass;
3788 int rc;
3789
3790 if (kern)
3791 return 0;
3792
3793 secclass = socket_type_to_security_class(family, type, protocol);
3794 rc = socket_sockcreate_sid(tsec, secclass, &newsid);
3795 if (rc)
3796 return rc;
3797
3798 return avc_has_perm(tsec->sid, newsid, secclass, SOCKET__CREATE, NULL);
3799 }
3800
3801 static int selinux_socket_post_create(struct socket *sock, int family,
3802 int type, int protocol, int kern)
3803 {
3804 const struct task_security_struct *tsec = current_security();
3805 struct inode_security_struct *isec = SOCK_INODE(sock)->i_security;
3806 struct sk_security_struct *sksec;
3807 int err = 0;
3808
3809 isec->sclass = socket_type_to_security_class(family, type, protocol);
3810
3811 if (kern)
3812 isec->sid = SECINITSID_KERNEL;
3813 else {
3814 err = socket_sockcreate_sid(tsec, isec->sclass, &(isec->sid));
3815 if (err)
3816 return err;
3817 }
3818
3819 isec->initialized = 1;
3820
3821 if (sock->sk) {
3822 sksec = sock->sk->sk_security;
3823 sksec->sid = isec->sid;
3824 sksec->sclass = isec->sclass;
3825 err = selinux_netlbl_socket_post_create(sock->sk, family);
3826 }
3827
3828 return err;
3829 }
3830
3831 /* Range of port numbers used to automatically bind.
3832 Need to determine whether we should perform a name_bind
3833 permission check between the socket and the port number. */
3834
3835 static int selinux_socket_bind(struct socket *sock, struct sockaddr *address, int addrlen)
3836 {
3837 struct sock *sk = sock->sk;
3838 u16 family;
3839 int err;
3840
3841 err = sock_has_perm(current, sk, SOCKET__BIND);
3842 if (err)
3843 goto out;
3844
3845 /*
3846 * If PF_INET or PF_INET6, check name_bind permission for the port.
3847 * Multiple address binding for SCTP is not supported yet: we just
3848 * check the first address now.
3849 */
3850 family = sk->sk_family;
3851 if (family == PF_INET || family == PF_INET6) {
3852 char *addrp;
3853 struct sk_security_struct *sksec = sk->sk_security;
3854 struct common_audit_data ad;
3855 struct lsm_network_audit net = {0,};
3856 struct sockaddr_in *addr4 = NULL;
3857 struct sockaddr_in6 *addr6 = NULL;
3858 unsigned short snum;
3859 u32 sid, node_perm;
3860
3861 if (family == PF_INET) {
3862 addr4 = (struct sockaddr_in *)address;
3863 snum = ntohs(addr4->sin_port);
3864 addrp = (char *)&addr4->sin_addr.s_addr;
3865 } else {
3866 addr6 = (struct sockaddr_in6 *)address;
3867 snum = ntohs(addr6->sin6_port);
3868 addrp = (char *)&addr6->sin6_addr.s6_addr;
3869 }
3870
3871 if (snum) {
3872 int low, high;
3873
3874 inet_get_local_port_range(&low, &high);
3875
3876 if (snum < max(PROT_SOCK, low) || snum > high) {
3877 err = sel_netport_sid(sk->sk_protocol,
3878 snum, &sid);
3879 if (err)
3880 goto out;
3881 ad.type = LSM_AUDIT_DATA_NET;
3882 ad.u.net = &net;
3883 ad.u.net->sport = htons(snum);
3884 ad.u.net->family = family;
3885 err = avc_has_perm(sksec->sid, sid,
3886 sksec->sclass,
3887 SOCKET__NAME_BIND, &ad);
3888 if (err)
3889 goto out;
3890 }
3891 }
3892
3893 switch (sksec->sclass) {
3894 case SECCLASS_TCP_SOCKET:
3895 node_perm = TCP_SOCKET__NODE_BIND;
3896 break;
3897
3898 case SECCLASS_UDP_SOCKET:
3899 node_perm = UDP_SOCKET__NODE_BIND;
3900 break;
3901
3902 case SECCLASS_DCCP_SOCKET:
3903 node_perm = DCCP_SOCKET__NODE_BIND;
3904 break;
3905
3906 default:
3907 node_perm = RAWIP_SOCKET__NODE_BIND;
3908 break;
3909 }
3910
3911 err = sel_netnode_sid(addrp, family, &sid);
3912 if (err)
3913 goto out;
3914
3915 ad.type = LSM_AUDIT_DATA_NET;
3916 ad.u.net = &net;
3917 ad.u.net->sport = htons(snum);
3918 ad.u.net->family = family;
3919
3920 if (family == PF_INET)
3921 ad.u.net->v4info.saddr = addr4->sin_addr.s_addr;
3922 else
3923 ad.u.net->v6info.saddr = addr6->sin6_addr;
3924
3925 err = avc_has_perm(sksec->sid, sid,
3926 sksec->sclass, node_perm, &ad);
3927 if (err)
3928 goto out;
3929 }
3930 out:
3931 return err;
3932 }
3933
3934 static int selinux_socket_connect(struct socket *sock, struct sockaddr *address, int addrlen)
3935 {
3936 struct sock *sk = sock->sk;
3937 struct sk_security_struct *sksec = sk->sk_security;
3938 int err;
3939
3940 err = sock_has_perm(current, sk, SOCKET__CONNECT);
3941 if (err)
3942 return err;
3943
3944 /*
3945 * If a TCP or DCCP socket, check name_connect permission for the port.
3946 */
3947 if (sksec->sclass == SECCLASS_TCP_SOCKET ||
3948 sksec->sclass == SECCLASS_DCCP_SOCKET) {
3949 struct common_audit_data ad;
3950 struct lsm_network_audit net = {0,};
3951 struct sockaddr_in *addr4 = NULL;
3952 struct sockaddr_in6 *addr6 = NULL;
3953 unsigned short snum;
3954 u32 sid, perm;
3955
3956 if (sk->sk_family == PF_INET) {
3957 addr4 = (struct sockaddr_in *)address;
3958 if (addrlen < sizeof(struct sockaddr_in))
3959 return -EINVAL;
3960 snum = ntohs(addr4->sin_port);
3961 } else {
3962 addr6 = (struct sockaddr_in6 *)address;
3963 if (addrlen < SIN6_LEN_RFC2133)
3964 return -EINVAL;
3965 snum = ntohs(addr6->sin6_port);
3966 }
3967
3968 err = sel_netport_sid(sk->sk_protocol, snum, &sid);
3969 if (err)
3970 goto out;
3971
3972 perm = (sksec->sclass == SECCLASS_TCP_SOCKET) ?
3973 TCP_SOCKET__NAME_CONNECT : DCCP_SOCKET__NAME_CONNECT;
3974
3975 ad.type = LSM_AUDIT_DATA_NET;
3976 ad.u.net = &net;
3977 ad.u.net->dport = htons(snum);
3978 ad.u.net->family = sk->sk_family;
3979 err = avc_has_perm(sksec->sid, sid, sksec->sclass, perm, &ad);
3980 if (err)
3981 goto out;
3982 }
3983
3984 err = selinux_netlbl_socket_connect(sk, address);
3985
3986 out:
3987 return err;
3988 }
3989
3990 static int selinux_socket_listen(struct socket *sock, int backlog)
3991 {
3992 return sock_has_perm(current, sock->sk, SOCKET__LISTEN);
3993 }
3994
3995 static int selinux_socket_accept(struct socket *sock, struct socket *newsock)
3996 {
3997 int err;
3998 struct inode_security_struct *isec;
3999 struct inode_security_struct *newisec;
4000
4001 err = sock_has_perm(current, sock->sk, SOCKET__ACCEPT);
4002 if (err)
4003 return err;
4004
4005 newisec = SOCK_INODE(newsock)->i_security;
4006
4007 isec = SOCK_INODE(sock)->i_security;
4008 newisec->sclass = isec->sclass;
4009 newisec->sid = isec->sid;
4010 newisec->initialized = 1;
4011
4012 return 0;
4013 }
4014
4015 static int selinux_socket_sendmsg(struct socket *sock, struct msghdr *msg,
4016 int size)
4017 {
4018 return sock_has_perm(current, sock->sk, SOCKET__WRITE);
4019 }
4020
4021 static int selinux_socket_recvmsg(struct socket *sock, struct msghdr *msg,
4022 int size, int flags)
4023 {
4024 return sock_has_perm(current, sock->sk, SOCKET__READ);
4025 }
4026
4027 static int selinux_socket_getsockname(struct socket *sock)
4028 {
4029 return sock_has_perm(current, sock->sk, SOCKET__GETATTR);
4030 }
4031
4032 static int selinux_socket_getpeername(struct socket *sock)
4033 {
4034 return sock_has_perm(current, sock->sk, SOCKET__GETATTR);
4035 }
4036
4037 static int selinux_socket_setsockopt(struct socket *sock, int level, int optname)
4038 {
4039 int err;
4040
4041 err = sock_has_perm(current, sock->sk, SOCKET__SETOPT);
4042 if (err)
4043 return err;
4044
4045 return selinux_netlbl_socket_setsockopt(sock, level, optname);
4046 }
4047
4048 static int selinux_socket_getsockopt(struct socket *sock, int level,
4049 int optname)
4050 {
4051 return sock_has_perm(current, sock->sk, SOCKET__GETOPT);
4052 }
4053
4054 static int selinux_socket_shutdown(struct socket *sock, int how)
4055 {
4056 return sock_has_perm(current, sock->sk, SOCKET__SHUTDOWN);
4057 }
4058
4059 static int selinux_socket_unix_stream_connect(struct sock *sock,
4060 struct sock *other,
4061 struct sock *newsk)
4062 {
4063 struct sk_security_struct *sksec_sock = sock->sk_security;
4064 struct sk_security_struct *sksec_other = other->sk_security;
4065 struct sk_security_struct *sksec_new = newsk->sk_security;
4066 struct common_audit_data ad;
4067 struct lsm_network_audit net = {0,};
4068 int err;
4069
4070 ad.type = LSM_AUDIT_DATA_NET;
4071 ad.u.net = &net;
4072 ad.u.net->sk = other;
4073
4074 err = avc_has_perm(sksec_sock->sid, sksec_other->sid,
4075 sksec_other->sclass,
4076 UNIX_STREAM_SOCKET__CONNECTTO, &ad);
4077 if (err)
4078 return err;
4079
4080 /* server child socket */
4081 sksec_new->peer_sid = sksec_sock->sid;
4082 err = security_sid_mls_copy(sksec_other->sid, sksec_sock->sid,
4083 &sksec_new->sid);
4084 if (err)
4085 return err;
4086
4087 /* connecting socket */
4088 sksec_sock->peer_sid = sksec_new->sid;
4089
4090 return 0;
4091 }
4092
4093 static int selinux_socket_unix_may_send(struct socket *sock,
4094 struct socket *other)
4095 {
4096 struct sk_security_struct *ssec = sock->sk->sk_security;
4097 struct sk_security_struct *osec = other->sk->sk_security;
4098 struct common_audit_data ad;
4099 struct lsm_network_audit net = {0,};
4100
4101 ad.type = LSM_AUDIT_DATA_NET;
4102 ad.u.net = &net;
4103 ad.u.net->sk = other->sk;
4104
4105 return avc_has_perm(ssec->sid, osec->sid, osec->sclass, SOCKET__SENDTO,
4106 &ad);
4107 }
4108
4109 static int selinux_inet_sys_rcv_skb(int ifindex, char *addrp, u16 family,
4110 u32 peer_sid,
4111 struct common_audit_data *ad)
4112 {
4113 int err;
4114 u32 if_sid;
4115 u32 node_sid;
4116
4117 err = sel_netif_sid(ifindex, &if_sid);
4118 if (err)
4119 return err;
4120 err = avc_has_perm(peer_sid, if_sid,
4121 SECCLASS_NETIF, NETIF__INGRESS, ad);
4122 if (err)
4123 return err;
4124
4125 err = sel_netnode_sid(addrp, family, &node_sid);
4126 if (err)
4127 return err;
4128 return avc_has_perm(peer_sid, node_sid,
4129 SECCLASS_NODE, NODE__RECVFROM, ad);
4130 }
4131
4132 static int selinux_sock_rcv_skb_compat(struct sock *sk, struct sk_buff *skb,
4133 u16 family)
4134 {
4135 int err = 0;
4136 struct sk_security_struct *sksec = sk->sk_security;
4137 u32 sk_sid = sksec->sid;
4138 struct common_audit_data ad;
4139 struct lsm_network_audit net = {0,};
4140 char *addrp;
4141
4142 ad.type = LSM_AUDIT_DATA_NET;
4143 ad.u.net = &net;
4144 ad.u.net->netif = skb->skb_iif;
4145 ad.u.net->family = family;
4146 err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL);
4147 if (err)
4148 return err;
4149
4150 if (selinux_secmark_enabled()) {
4151 err = avc_has_perm(sk_sid, skb->secmark, SECCLASS_PACKET,
4152 PACKET__RECV, &ad);
4153 if (err)
4154 return err;
4155 }
4156
4157 err = selinux_netlbl_sock_rcv_skb(sksec, skb, family, &ad);
4158 if (err)
4159 return err;
4160 err = selinux_xfrm_sock_rcv_skb(sksec->sid, skb, &ad);
4161
4162 return err;
4163 }
4164
4165 static int selinux_socket_sock_rcv_skb(struct sock *sk, struct sk_buff *skb)
4166 {
4167 int err;
4168 struct sk_security_struct *sksec = sk->sk_security;
4169 u16 family = sk->sk_family;
4170 u32 sk_sid = sksec->sid;
4171 struct common_audit_data ad;
4172 struct lsm_network_audit net = {0,};
4173 char *addrp;
4174 u8 secmark_active;
4175 u8 peerlbl_active;
4176
4177 if (family != PF_INET && family != PF_INET6)
4178 return 0;
4179
4180 /* Handle mapped IPv4 packets arriving via IPv6 sockets */
4181 if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
4182 family = PF_INET;
4183
4184 /* If any sort of compatibility mode is enabled then handoff processing
4185 * to the selinux_sock_rcv_skb_compat() function to deal with the
4186 * special handling. We do this in an attempt to keep this function
4187 * as fast and as clean as possible. */
4188 if (!selinux_policycap_netpeer)
4189 return selinux_sock_rcv_skb_compat(sk, skb, family);
4190
4191 secmark_active = selinux_secmark_enabled();
4192 peerlbl_active = netlbl_enabled() || selinux_xfrm_enabled();
4193 if (!secmark_active && !peerlbl_active)
4194 return 0;
4195
4196 ad.type = LSM_AUDIT_DATA_NET;
4197 ad.u.net = &net;
4198 ad.u.net->netif = skb->skb_iif;
4199 ad.u.net->family = family;
4200 err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL);
4201 if (err)
4202 return err;
4203
4204 if (peerlbl_active) {
4205 u32 peer_sid;
4206
4207 err = selinux_skb_peerlbl_sid(skb, family, &peer_sid);
4208 if (err)
4209 return err;
4210 err = selinux_inet_sys_rcv_skb(skb->skb_iif, addrp, family,
4211 peer_sid, &ad);
4212 if (err) {
4213 selinux_netlbl_err(skb, err, 0);
4214 return err;
4215 }
4216 err = avc_has_perm(sk_sid, peer_sid, SECCLASS_PEER,
4217 PEER__RECV, &ad);
4218 if (err)
4219 selinux_netlbl_err(skb, err, 0);
4220 }
4221
4222 if (secmark_active) {
4223 err = avc_has_perm(sk_sid, skb->secmark, SECCLASS_PACKET,
4224 PACKET__RECV, &ad);
4225 if (err)
4226 return err;
4227 }
4228
4229 return err;
4230 }
4231
4232 static int selinux_socket_getpeersec_stream(struct socket *sock, char __user *optval,
4233 int __user *optlen, unsigned len)
4234 {
4235 int err = 0;
4236 char *scontext;
4237 u32 scontext_len;
4238 struct sk_security_struct *sksec = sock->sk->sk_security;
4239 u32 peer_sid = SECSID_NULL;
4240
4241 if (sksec->sclass == SECCLASS_UNIX_STREAM_SOCKET ||
4242 sksec->sclass == SECCLASS_TCP_SOCKET)
4243 peer_sid = sksec->peer_sid;
4244 if (peer_sid == SECSID_NULL)
4245 return -ENOPROTOOPT;
4246
4247 err = security_sid_to_context(peer_sid, &scontext, &scontext_len);
4248 if (err)
4249 return err;
4250
4251 if (scontext_len > len) {
4252 err = -ERANGE;
4253 goto out_len;
4254 }
4255
4256 if (copy_to_user(optval, scontext, scontext_len))
4257 err = -EFAULT;
4258
4259 out_len:
4260 if (put_user(scontext_len, optlen))
4261 err = -EFAULT;
4262 kfree(scontext);
4263 return err;
4264 }
4265
4266 static int selinux_socket_getpeersec_dgram(struct socket *sock, struct sk_buff *skb, u32 *secid)
4267 {
4268 u32 peer_secid = SECSID_NULL;
4269 u16 family;
4270
4271 if (skb && skb->protocol == htons(ETH_P_IP))
4272 family = PF_INET;
4273 else if (skb && skb->protocol == htons(ETH_P_IPV6))
4274 family = PF_INET6;
4275 else if (sock)
4276 family = sock->sk->sk_family;
4277 else
4278 goto out;
4279
4280 if (sock && family == PF_UNIX)
4281 selinux_inode_getsecid(SOCK_INODE(sock), &peer_secid);
4282 else if (skb)
4283 selinux_skb_peerlbl_sid(skb, family, &peer_secid);
4284
4285 out:
4286 *secid = peer_secid;
4287 if (peer_secid == SECSID_NULL)
4288 return -EINVAL;
4289 return 0;
4290 }
4291
4292 static int selinux_sk_alloc_security(struct sock *sk, int family, gfp_t priority)
4293 {
4294 struct sk_security_struct *sksec;
4295
4296 sksec = kzalloc(sizeof(*sksec), priority);
4297 if (!sksec)
4298 return -ENOMEM;
4299
4300 sksec->peer_sid = SECINITSID_UNLABELED;
4301 sksec->sid = SECINITSID_UNLABELED;
4302 selinux_netlbl_sk_security_reset(sksec);
4303 sk->sk_security = sksec;
4304
4305 return 0;
4306 }
4307
4308 static void selinux_sk_free_security(struct sock *sk)
4309 {
4310 struct sk_security_struct *sksec = sk->sk_security;
4311
4312 sk->sk_security = NULL;
4313 selinux_netlbl_sk_security_free(sksec);
4314 kfree(sksec);
4315 }
4316
4317 static void selinux_sk_clone_security(const struct sock *sk, struct sock *newsk)
4318 {
4319 struct sk_security_struct *sksec = sk->sk_security;
4320 struct sk_security_struct *newsksec = newsk->sk_security;
4321
4322 newsksec->sid = sksec->sid;
4323 newsksec->peer_sid = sksec->peer_sid;
4324 newsksec->sclass = sksec->sclass;
4325
4326 selinux_netlbl_sk_security_reset(newsksec);
4327 }
4328
4329 static void selinux_sk_getsecid(struct sock *sk, u32 *secid)
4330 {
4331 if (!sk)
4332 *secid = SECINITSID_ANY_SOCKET;
4333 else {
4334 struct sk_security_struct *sksec = sk->sk_security;
4335
4336 *secid = sksec->sid;
4337 }
4338 }
4339
4340 static void selinux_sock_graft(struct sock *sk, struct socket *parent)
4341 {
4342 struct inode_security_struct *isec = SOCK_INODE(parent)->i_security;
4343 struct sk_security_struct *sksec = sk->sk_security;
4344
4345 if (sk->sk_family == PF_INET || sk->sk_family == PF_INET6 ||
4346 sk->sk_family == PF_UNIX)
4347 isec->sid = sksec->sid;
4348 sksec->sclass = isec->sclass;
4349 }
4350
4351 static int selinux_inet_conn_request(struct sock *sk, struct sk_buff *skb,
4352 struct request_sock *req)
4353 {
4354 struct sk_security_struct *sksec = sk->sk_security;
4355 int err;
4356 u16 family = sk->sk_family;
4357 u32 newsid;
4358 u32 peersid;
4359
4360 /* handle mapped IPv4 packets arriving via IPv6 sockets */
4361 if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
4362 family = PF_INET;
4363
4364 err = selinux_skb_peerlbl_sid(skb, family, &peersid);
4365 if (err)
4366 return err;
4367 if (peersid == SECSID_NULL) {
4368 req->secid = sksec->sid;
4369 req->peer_secid = SECSID_NULL;
4370 } else {
4371 err = security_sid_mls_copy(sksec->sid, peersid, &newsid);
4372 if (err)
4373 return err;
4374 req->secid = newsid;
4375 req->peer_secid = peersid;
4376 }
4377
4378 return selinux_netlbl_inet_conn_request(req, family);
4379 }
4380
4381 static void selinux_inet_csk_clone(struct sock *newsk,
4382 const struct request_sock *req)
4383 {
4384 struct sk_security_struct *newsksec = newsk->sk_security;
4385
4386 newsksec->sid = req->secid;
4387 newsksec->peer_sid = req->peer_secid;
4388 /* NOTE: Ideally, we should also get the isec->sid for the
4389 new socket in sync, but we don't have the isec available yet.
4390 So we will wait until sock_graft to do it, by which
4391 time it will have been created and available. */
4392
4393 /* We don't need to take any sort of lock here as we are the only
4394 * thread with access to newsksec */
4395 selinux_netlbl_inet_csk_clone(newsk, req->rsk_ops->family);
4396 }
4397
4398 static void selinux_inet_conn_established(struct sock *sk, struct sk_buff *skb)
4399 {
4400 u16 family = sk->sk_family;
4401 struct sk_security_struct *sksec = sk->sk_security;
4402
4403 /* handle mapped IPv4 packets arriving via IPv6 sockets */
4404 if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
4405 family = PF_INET;
4406
4407 selinux_skb_peerlbl_sid(skb, family, &sksec->peer_sid);
4408 }
4409
4410 static void selinux_skb_owned_by(struct sk_buff *skb, struct sock *sk)
4411 {
4412 skb_set_owner_w(skb, sk);
4413 }
4414
4415 static int selinux_secmark_relabel_packet(u32 sid)
4416 {
4417 const struct task_security_struct *__tsec;
4418 u32 tsid;
4419
4420 __tsec = current_security();
4421 tsid = __tsec->sid;
4422
4423 return avc_has_perm(tsid, sid, SECCLASS_PACKET, PACKET__RELABELTO, NULL);
4424 }
4425
4426 static void selinux_secmark_refcount_inc(void)
4427 {
4428 atomic_inc(&selinux_secmark_refcount);
4429 }
4430
4431 static void selinux_secmark_refcount_dec(void)
4432 {
4433 atomic_dec(&selinux_secmark_refcount);
4434 }
4435
4436 static void selinux_req_classify_flow(const struct request_sock *req,
4437 struct flowi *fl)
4438 {
4439 fl->flowi_secid = req->secid;
4440 }
4441
4442 static int selinux_tun_dev_alloc_security(void **security)
4443 {
4444 struct tun_security_struct *tunsec;
4445
4446 tunsec = kzalloc(sizeof(*tunsec), GFP_KERNEL);
4447 if (!tunsec)
4448 return -ENOMEM;
4449 tunsec->sid = current_sid();
4450
4451 *security = tunsec;
4452 return 0;
4453 }
4454
4455 static void selinux_tun_dev_free_security(void *security)
4456 {
4457 kfree(security);
4458 }
4459
4460 static int selinux_tun_dev_create(void)
4461 {
4462 u32 sid = current_sid();
4463
4464 /* we aren't taking into account the "sockcreate" SID since the socket
4465 * that is being created here is not a socket in the traditional sense,
4466 * instead it is a private sock, accessible only to the kernel, and
4467 * representing a wide range of network traffic spanning multiple
4468 * connections unlike traditional sockets - check the TUN driver to
4469 * get a better understanding of why this socket is special */
4470
4471 return avc_has_perm(sid, sid, SECCLASS_TUN_SOCKET, TUN_SOCKET__CREATE,
4472 NULL);
4473 }
4474
4475 static int selinux_tun_dev_attach_queue(void *security)
4476 {
4477 struct tun_security_struct *tunsec = security;
4478
4479 return avc_has_perm(current_sid(), tunsec->sid, SECCLASS_TUN_SOCKET,
4480 TUN_SOCKET__ATTACH_QUEUE, NULL);
4481 }
4482
4483 static int selinux_tun_dev_attach(struct sock *sk, void *security)
4484 {
4485 struct tun_security_struct *tunsec = security;
4486 struct sk_security_struct *sksec = sk->sk_security;
4487
4488 /* we don't currently perform any NetLabel based labeling here and it
4489 * isn't clear that we would want to do so anyway; while we could apply
4490 * labeling without the support of the TUN user the resulting labeled
4491 * traffic from the other end of the connection would almost certainly
4492 * cause confusion to the TUN user that had no idea network labeling
4493 * protocols were being used */
4494
4495 sksec->sid = tunsec->sid;
4496 sksec->sclass = SECCLASS_TUN_SOCKET;
4497
4498 return 0;
4499 }
4500
4501 static int selinux_tun_dev_open(void *security)
4502 {
4503 struct tun_security_struct *tunsec = security;
4504 u32 sid = current_sid();
4505 int err;
4506
4507 err = avc_has_perm(sid, tunsec->sid, SECCLASS_TUN_SOCKET,
4508 TUN_SOCKET__RELABELFROM, NULL);
4509 if (err)
4510 return err;
4511 err = avc_has_perm(sid, sid, SECCLASS_TUN_SOCKET,
4512 TUN_SOCKET__RELABELTO, NULL);
4513 if (err)
4514 return err;
4515 tunsec->sid = sid;
4516
4517 return 0;
4518 }
4519
4520 static int selinux_nlmsg_perm(struct sock *sk, struct sk_buff *skb)
4521 {
4522 int err = 0;
4523 u32 perm;
4524 struct nlmsghdr *nlh;
4525 struct sk_security_struct *sksec = sk->sk_security;
4526
4527 if (skb->len < NLMSG_HDRLEN) {
4528 err = -EINVAL;
4529 goto out;
4530 }
4531 nlh = nlmsg_hdr(skb);
4532
4533 err = selinux_nlmsg_lookup(sksec->sclass, nlh->nlmsg_type, &perm);
4534 if (err) {
4535 if (err == -EINVAL) {
4536 audit_log(current->audit_context, GFP_KERNEL, AUDIT_SELINUX_ERR,
4537 "SELinux: unrecognized netlink message"
4538 " type=%hu for sclass=%hu\n",
4539 nlh->nlmsg_type, sksec->sclass);
4540 if (!selinux_enforcing || security_get_allow_unknown())
4541 err = 0;
4542 }
4543
4544 /* Ignore */
4545 if (err == -ENOENT)
4546 err = 0;
4547 goto out;
4548 }
4549
4550 err = sock_has_perm(current, sk, perm);
4551 out:
4552 return err;
4553 }
4554
4555 #ifdef CONFIG_NETFILTER
4556
4557 static unsigned int selinux_ip_forward(struct sk_buff *skb, int ifindex,
4558 u16 family)
4559 {
4560 int err;
4561 char *addrp;
4562 u32 peer_sid;
4563 struct common_audit_data ad;
4564 struct lsm_network_audit net = {0,};
4565 u8 secmark_active;
4566 u8 netlbl_active;
4567 u8 peerlbl_active;
4568
4569 if (!selinux_policycap_netpeer)
4570 return NF_ACCEPT;
4571
4572 secmark_active = selinux_secmark_enabled();
4573 netlbl_active = netlbl_enabled();
4574 peerlbl_active = netlbl_active || selinux_xfrm_enabled();
4575 if (!secmark_active && !peerlbl_active)
4576 return NF_ACCEPT;
4577
4578 if (selinux_skb_peerlbl_sid(skb, family, &peer_sid) != 0)
4579 return NF_DROP;
4580
4581 ad.type = LSM_AUDIT_DATA_NET;
4582 ad.u.net = &net;
4583 ad.u.net->netif = ifindex;
4584 ad.u.net->family = family;
4585 if (selinux_parse_skb(skb, &ad, &addrp, 1, NULL) != 0)
4586 return NF_DROP;
4587
4588 if (peerlbl_active) {
4589 err = selinux_inet_sys_rcv_skb(ifindex, addrp, family,
4590 peer_sid, &ad);
4591 if (err) {
4592 selinux_netlbl_err(skb, err, 1);
4593 return NF_DROP;
4594 }
4595 }
4596
4597 if (secmark_active)
4598 if (avc_has_perm(peer_sid, skb->secmark,
4599 SECCLASS_PACKET, PACKET__FORWARD_IN, &ad))
4600 return NF_DROP;
4601
4602 if (netlbl_active)
4603 /* we do this in the FORWARD path and not the POST_ROUTING
4604 * path because we want to make sure we apply the necessary
4605 * labeling before IPsec is applied so we can leverage AH
4606 * protection */
4607 if (selinux_netlbl_skbuff_setsid(skb, family, peer_sid) != 0)
4608 return NF_DROP;
4609
4610 return NF_ACCEPT;
4611 }
4612
4613 static unsigned int selinux_ipv4_forward(unsigned int hooknum,
4614 struct sk_buff *skb,
4615 const struct net_device *in,
4616 const struct net_device *out,
4617 int (*okfn)(struct sk_buff *))
4618 {
4619 return selinux_ip_forward(skb, in->ifindex, PF_INET);
4620 }
4621
4622 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
4623 static unsigned int selinux_ipv6_forward(unsigned int hooknum,
4624 struct sk_buff *skb,
4625 const struct net_device *in,
4626 const struct net_device *out,
4627 int (*okfn)(struct sk_buff *))
4628 {
4629 return selinux_ip_forward(skb, in->ifindex, PF_INET6);
4630 }
4631 #endif /* IPV6 */
4632
4633 static unsigned int selinux_ip_output(struct sk_buff *skb,
4634 u16 family)
4635 {
4636 u32 sid;
4637
4638 if (!netlbl_enabled())
4639 return NF_ACCEPT;
4640
4641 /* we do this in the LOCAL_OUT path and not the POST_ROUTING path
4642 * because we want to make sure we apply the necessary labeling
4643 * before IPsec is applied so we can leverage AH protection */
4644 if (skb->sk) {
4645 struct sk_security_struct *sksec = skb->sk->sk_security;
4646 sid = sksec->sid;
4647 } else
4648 sid = SECINITSID_KERNEL;
4649 if (selinux_netlbl_skbuff_setsid(skb, family, sid) != 0)
4650 return NF_DROP;
4651
4652 return NF_ACCEPT;
4653 }
4654
4655 static unsigned int selinux_ipv4_output(unsigned int hooknum,
4656 struct sk_buff *skb,
4657 const struct net_device *in,
4658 const struct net_device *out,
4659 int (*okfn)(struct sk_buff *))
4660 {
4661 return selinux_ip_output(skb, PF_INET);
4662 }
4663
4664 static unsigned int selinux_ip_postroute_compat(struct sk_buff *skb,
4665 int ifindex,
4666 u16 family)
4667 {
4668 struct sock *sk = skb->sk;
4669 struct sk_security_struct *sksec;
4670 struct common_audit_data ad;
4671 struct lsm_network_audit net = {0,};
4672 char *addrp;
4673 u8 proto;
4674
4675 if (sk == NULL)
4676 return NF_ACCEPT;
4677 sksec = sk->sk_security;
4678
4679 ad.type = LSM_AUDIT_DATA_NET;
4680 ad.u.net = &net;
4681 ad.u.net->netif = ifindex;
4682 ad.u.net->family = family;
4683 if (selinux_parse_skb(skb, &ad, &addrp, 0, &proto))
4684 return NF_DROP;
4685
4686 if (selinux_secmark_enabled())
4687 if (avc_has_perm(sksec->sid, skb->secmark,
4688 SECCLASS_PACKET, PACKET__SEND, &ad))
4689 return NF_DROP_ERR(-ECONNREFUSED);
4690
4691 if (selinux_xfrm_postroute_last(sksec->sid, skb, &ad, proto))
4692 return NF_DROP_ERR(-ECONNREFUSED);
4693
4694 return NF_ACCEPT;
4695 }
4696
4697 static unsigned int selinux_ip_postroute(struct sk_buff *skb, int ifindex,
4698 u16 family)
4699 {
4700 u32 secmark_perm;
4701 u32 peer_sid;
4702 struct sock *sk;
4703 struct common_audit_data ad;
4704 struct lsm_network_audit net = {0,};
4705 char *addrp;
4706 u8 secmark_active;
4707 u8 peerlbl_active;
4708
4709 /* If any sort of compatibility mode is enabled then handoff processing
4710 * to the selinux_ip_postroute_compat() function to deal with the
4711 * special handling. We do this in an attempt to keep this function
4712 * as fast and as clean as possible. */
4713 if (!selinux_policycap_netpeer)
4714 return selinux_ip_postroute_compat(skb, ifindex, family);
4715 #ifdef CONFIG_XFRM
4716 /* If skb->dst->xfrm is non-NULL then the packet is undergoing an IPsec
4717 * packet transformation so allow the packet to pass without any checks
4718 * since we'll have another chance to perform access control checks
4719 * when the packet is on it's final way out.
4720 * NOTE: there appear to be some IPv6 multicast cases where skb->dst
4721 * is NULL, in this case go ahead and apply access control. */
4722 if (skb_dst(skb) != NULL && skb_dst(skb)->xfrm != NULL)
4723 return NF_ACCEPT;
4724 #endif
4725 secmark_active = selinux_secmark_enabled();
4726 peerlbl_active = netlbl_enabled() || selinux_xfrm_enabled();
4727 if (!secmark_active && !peerlbl_active)
4728 return NF_ACCEPT;
4729
4730 /* if the packet is being forwarded then get the peer label from the
4731 * packet itself; otherwise check to see if it is from a local
4732 * application or the kernel, if from an application get the peer label
4733 * from the sending socket, otherwise use the kernel's sid */
4734 sk = skb->sk;
4735 if (sk == NULL) {
4736 if (skb->skb_iif) {
4737 secmark_perm = PACKET__FORWARD_OUT;
4738 if (selinux_skb_peerlbl_sid(skb, family, &peer_sid))
4739 return NF_DROP;
4740 } else {
4741 secmark_perm = PACKET__SEND;
4742 peer_sid = SECINITSID_KERNEL;
4743 }
4744 } else {
4745 struct sk_security_struct *sksec = sk->sk_security;
4746 peer_sid = sksec->sid;
4747 secmark_perm = PACKET__SEND;
4748 }
4749
4750 ad.type = LSM_AUDIT_DATA_NET;
4751 ad.u.net = &net;
4752 ad.u.net->netif = ifindex;
4753 ad.u.net->family = family;
4754 if (selinux_parse_skb(skb, &ad, &addrp, 0, NULL))
4755 return NF_DROP;
4756
4757 if (secmark_active)
4758 if (avc_has_perm(peer_sid, skb->secmark,
4759 SECCLASS_PACKET, secmark_perm, &ad))
4760 return NF_DROP_ERR(-ECONNREFUSED);
4761
4762 if (peerlbl_active) {
4763 u32 if_sid;
4764 u32 node_sid;
4765
4766 if (sel_netif_sid(ifindex, &if_sid))
4767 return NF_DROP;
4768 if (avc_has_perm(peer_sid, if_sid,
4769 SECCLASS_NETIF, NETIF__EGRESS, &ad))
4770 return NF_DROP_ERR(-ECONNREFUSED);
4771
4772 if (sel_netnode_sid(addrp, family, &node_sid))
4773 return NF_DROP;
4774 if (avc_has_perm(peer_sid, node_sid,
4775 SECCLASS_NODE, NODE__SENDTO, &ad))
4776 return NF_DROP_ERR(-ECONNREFUSED);
4777 }
4778
4779 return NF_ACCEPT;
4780 }
4781
4782 static unsigned int selinux_ipv4_postroute(unsigned int hooknum,
4783 struct sk_buff *skb,
4784 const struct net_device *in,
4785 const struct net_device *out,
4786 int (*okfn)(struct sk_buff *))
4787 {
4788 return selinux_ip_postroute(skb, out->ifindex, PF_INET);
4789 }
4790
4791 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
4792 static unsigned int selinux_ipv6_postroute(unsigned int hooknum,
4793 struct sk_buff *skb,
4794 const struct net_device *in,
4795 const struct net_device *out,
4796 int (*okfn)(struct sk_buff *))
4797 {
4798 return selinux_ip_postroute(skb, out->ifindex, PF_INET6);
4799 }
4800 #endif /* IPV6 */
4801
4802 #endif /* CONFIG_NETFILTER */
4803
4804 static int selinux_netlink_send(struct sock *sk, struct sk_buff *skb)
4805 {
4806 int err;
4807
4808 err = cap_netlink_send(sk, skb);
4809 if (err)
4810 return err;
4811
4812 return selinux_nlmsg_perm(sk, skb);
4813 }
4814
4815 static int ipc_alloc_security(struct task_struct *task,
4816 struct kern_ipc_perm *perm,
4817 u16 sclass)
4818 {
4819 struct ipc_security_struct *isec;
4820 u32 sid;
4821
4822 isec = kzalloc(sizeof(struct ipc_security_struct), GFP_KERNEL);
4823 if (!isec)
4824 return -ENOMEM;
4825
4826 sid = task_sid(task);
4827 isec->sclass = sclass;
4828 isec->sid = sid;
4829 perm->security = isec;
4830
4831 return 0;
4832 }
4833
4834 static void ipc_free_security(struct kern_ipc_perm *perm)
4835 {
4836 struct ipc_security_struct *isec = perm->security;
4837 perm->security = NULL;
4838 kfree(isec);
4839 }
4840
4841 static int msg_msg_alloc_security(struct msg_msg *msg)
4842 {
4843 struct msg_security_struct *msec;
4844
4845 msec = kzalloc(sizeof(struct msg_security_struct), GFP_KERNEL);
4846 if (!msec)
4847 return -ENOMEM;
4848
4849 msec->sid = SECINITSID_UNLABELED;
4850 msg->security = msec;
4851
4852 return 0;
4853 }
4854
4855 static void msg_msg_free_security(struct msg_msg *msg)
4856 {
4857 struct msg_security_struct *msec = msg->security;
4858
4859 msg->security = NULL;
4860 kfree(msec);
4861 }
4862
4863 static int ipc_has_perm(struct kern_ipc_perm *ipc_perms,
4864 u32 perms)
4865 {
4866 struct ipc_security_struct *isec;
4867 struct common_audit_data ad;
4868 u32 sid = current_sid();
4869
4870 isec = ipc_perms->security;
4871
4872 ad.type = LSM_AUDIT_DATA_IPC;
4873 ad.u.ipc_id = ipc_perms->key;
4874
4875 return avc_has_perm(sid, isec->sid, isec->sclass, perms, &ad);
4876 }
4877
4878 static int selinux_msg_msg_alloc_security(struct msg_msg *msg)
4879 {
4880 return msg_msg_alloc_security(msg);
4881 }
4882
4883 static void selinux_msg_msg_free_security(struct msg_msg *msg)
4884 {
4885 msg_msg_free_security(msg);
4886 }
4887
4888 /* message queue security operations */
4889 static int selinux_msg_queue_alloc_security(struct msg_queue *msq)
4890 {
4891 struct ipc_security_struct *isec;
4892 struct common_audit_data ad;
4893 u32 sid = current_sid();
4894 int rc;
4895
4896 rc = ipc_alloc_security(current, &msq->q_perm, SECCLASS_MSGQ);
4897 if (rc)
4898 return rc;
4899
4900 isec = msq->q_perm.security;
4901
4902 ad.type = LSM_AUDIT_DATA_IPC;
4903 ad.u.ipc_id = msq->q_perm.key;
4904
4905 rc = avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
4906 MSGQ__CREATE, &ad);
4907 if (rc) {
4908 ipc_free_security(&msq->q_perm);
4909 return rc;
4910 }
4911 return 0;
4912 }
4913
4914 static void selinux_msg_queue_free_security(struct msg_queue *msq)
4915 {
4916 ipc_free_security(&msq->q_perm);
4917 }
4918
4919 static int selinux_msg_queue_associate(struct msg_queue *msq, int msqflg)
4920 {
4921 struct ipc_security_struct *isec;
4922 struct common_audit_data ad;
4923 u32 sid = current_sid();
4924
4925 isec = msq->q_perm.security;
4926
4927 ad.type = LSM_AUDIT_DATA_IPC;
4928 ad.u.ipc_id = msq->q_perm.key;
4929
4930 return avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
4931 MSGQ__ASSOCIATE, &ad);
4932 }
4933
4934 static int selinux_msg_queue_msgctl(struct msg_queue *msq, int cmd)
4935 {
4936 int err;
4937 int perms;
4938
4939 switch (cmd) {
4940 case IPC_INFO:
4941 case MSG_INFO:
4942 /* No specific object, just general system-wide information. */
4943 return task_has_system(current, SYSTEM__IPC_INFO);
4944 case IPC_STAT:
4945 case MSG_STAT:
4946 perms = MSGQ__GETATTR | MSGQ__ASSOCIATE;
4947 break;
4948 case IPC_SET:
4949 perms = MSGQ__SETATTR;
4950 break;
4951 case IPC_RMID:
4952 perms = MSGQ__DESTROY;
4953 break;
4954 default:
4955 return 0;
4956 }
4957
4958 err = ipc_has_perm(&msq->q_perm, perms);
4959 return err;
4960 }
4961
4962 static int selinux_msg_queue_msgsnd(struct msg_queue *msq, struct msg_msg *msg, int msqflg)
4963 {
4964 struct ipc_security_struct *isec;
4965 struct msg_security_struct *msec;
4966 struct common_audit_data ad;
4967 u32 sid = current_sid();
4968 int rc;
4969
4970 isec = msq->q_perm.security;
4971 msec = msg->security;
4972
4973 /*
4974 * First time through, need to assign label to the message
4975 */
4976 if (msec->sid == SECINITSID_UNLABELED) {
4977 /*
4978 * Compute new sid based on current process and
4979 * message queue this message will be stored in
4980 */
4981 rc = security_transition_sid(sid, isec->sid, SECCLASS_MSG,
4982 NULL, &msec->sid);
4983 if (rc)
4984 return rc;
4985 }
4986
4987 ad.type = LSM_AUDIT_DATA_IPC;
4988 ad.u.ipc_id = msq->q_perm.key;
4989
4990 /* Can this process write to the queue? */
4991 rc = avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
4992 MSGQ__WRITE, &ad);
4993 if (!rc)
4994 /* Can this process send the message */
4995 rc = avc_has_perm(sid, msec->sid, SECCLASS_MSG,
4996 MSG__SEND, &ad);
4997 if (!rc)
4998 /* Can the message be put in the queue? */
4999 rc = avc_has_perm(msec->sid, isec->sid, SECCLASS_MSGQ,
5000 MSGQ__ENQUEUE, &ad);
5001
5002 return rc;
5003 }
5004
5005 static int selinux_msg_queue_msgrcv(struct msg_queue *msq, struct msg_msg *msg,
5006 struct task_struct *target,
5007 long type, int mode)
5008 {
5009 struct ipc_security_struct *isec;
5010 struct msg_security_struct *msec;
5011 struct common_audit_data ad;
5012 u32 sid = task_sid(target);
5013 int rc;
5014
5015 isec = msq->q_perm.security;
5016 msec = msg->security;
5017
5018 ad.type = LSM_AUDIT_DATA_IPC;
5019 ad.u.ipc_id = msq->q_perm.key;
5020
5021 rc = avc_has_perm(sid, isec->sid,
5022 SECCLASS_MSGQ, MSGQ__READ, &ad);
5023 if (!rc)
5024 rc = avc_has_perm(sid, msec->sid,
5025 SECCLASS_MSG, MSG__RECEIVE, &ad);
5026 return rc;
5027 }
5028
5029 /* Shared Memory security operations */
5030 static int selinux_shm_alloc_security(struct shmid_kernel *shp)
5031 {
5032 struct ipc_security_struct *isec;
5033 struct common_audit_data ad;
5034 u32 sid = current_sid();
5035 int rc;
5036
5037 rc = ipc_alloc_security(current, &shp->shm_perm, SECCLASS_SHM);
5038 if (rc)
5039 return rc;
5040
5041 isec = shp->shm_perm.security;
5042
5043 ad.type = LSM_AUDIT_DATA_IPC;
5044 ad.u.ipc_id = shp->shm_perm.key;
5045
5046 rc = avc_has_perm(sid, isec->sid, SECCLASS_SHM,
5047 SHM__CREATE, &ad);
5048 if (rc) {
5049 ipc_free_security(&shp->shm_perm);
5050 return rc;
5051 }
5052 return 0;
5053 }
5054
5055 static void selinux_shm_free_security(struct shmid_kernel *shp)
5056 {
5057 ipc_free_security(&shp->shm_perm);
5058 }
5059
5060 static int selinux_shm_associate(struct shmid_kernel *shp, int shmflg)
5061 {
5062 struct ipc_security_struct *isec;
5063 struct common_audit_data ad;
5064 u32 sid = current_sid();
5065
5066 isec = shp->shm_perm.security;
5067
5068 ad.type = LSM_AUDIT_DATA_IPC;
5069 ad.u.ipc_id = shp->shm_perm.key;
5070
5071 return avc_has_perm(sid, isec->sid, SECCLASS_SHM,
5072 SHM__ASSOCIATE, &ad);
5073 }
5074
5075 /* Note, at this point, shp is locked down */
5076 static int selinux_shm_shmctl(struct shmid_kernel *shp, int cmd)
5077 {
5078 int perms;
5079 int err;
5080
5081 switch (cmd) {
5082 case IPC_INFO:
5083 case SHM_INFO:
5084 /* No specific object, just general system-wide information. */
5085 return task_has_system(current, SYSTEM__IPC_INFO);
5086 case IPC_STAT:
5087 case SHM_STAT:
5088 perms = SHM__GETATTR | SHM__ASSOCIATE;
5089 break;
5090 case IPC_SET:
5091 perms = SHM__SETATTR;
5092 break;
5093 case SHM_LOCK:
5094 case SHM_UNLOCK:
5095 perms = SHM__LOCK;
5096 break;
5097 case IPC_RMID:
5098 perms = SHM__DESTROY;
5099 break;
5100 default:
5101 return 0;
5102 }
5103
5104 err = ipc_has_perm(&shp->shm_perm, perms);
5105 return err;
5106 }
5107
5108 static int selinux_shm_shmat(struct shmid_kernel *shp,
5109 char __user *shmaddr, int shmflg)
5110 {
5111 u32 perms;
5112
5113 if (shmflg & SHM_RDONLY)
5114 perms = SHM__READ;
5115 else
5116 perms = SHM__READ | SHM__WRITE;
5117
5118 return ipc_has_perm(&shp->shm_perm, perms);
5119 }
5120
5121 /* Semaphore security operations */
5122 static int selinux_sem_alloc_security(struct sem_array *sma)
5123 {
5124 struct ipc_security_struct *isec;
5125 struct common_audit_data ad;
5126 u32 sid = current_sid();
5127 int rc;
5128
5129 rc = ipc_alloc_security(current, &sma->sem_perm, SECCLASS_SEM);
5130 if (rc)
5131 return rc;
5132
5133 isec = sma->sem_perm.security;
5134
5135 ad.type = LSM_AUDIT_DATA_IPC;
5136 ad.u.ipc_id = sma->sem_perm.key;
5137
5138 rc = avc_has_perm(sid, isec->sid, SECCLASS_SEM,
5139 SEM__CREATE, &ad);
5140 if (rc) {
5141 ipc_free_security(&sma->sem_perm);
5142 return rc;
5143 }
5144 return 0;
5145 }
5146
5147 static void selinux_sem_free_security(struct sem_array *sma)
5148 {
5149 ipc_free_security(&sma->sem_perm);
5150 }
5151
5152 static int selinux_sem_associate(struct sem_array *sma, int semflg)
5153 {
5154 struct ipc_security_struct *isec;
5155 struct common_audit_data ad;
5156 u32 sid = current_sid();
5157
5158 isec = sma->sem_perm.security;
5159
5160 ad.type = LSM_AUDIT_DATA_IPC;
5161 ad.u.ipc_id = sma->sem_perm.key;
5162
5163 return avc_has_perm(sid, isec->sid, SECCLASS_SEM,
5164 SEM__ASSOCIATE, &ad);
5165 }
5166
5167 /* Note, at this point, sma is locked down */
5168 static int selinux_sem_semctl(struct sem_array *sma, int cmd)
5169 {
5170 int err;
5171 u32 perms;
5172
5173 switch (cmd) {
5174 case IPC_INFO:
5175 case SEM_INFO:
5176 /* No specific object, just general system-wide information. */
5177 return task_has_system(current, SYSTEM__IPC_INFO);
5178 case GETPID:
5179 case GETNCNT:
5180 case GETZCNT:
5181 perms = SEM__GETATTR;
5182 break;
5183 case GETVAL:
5184 case GETALL:
5185 perms = SEM__READ;
5186 break;
5187 case SETVAL:
5188 case SETALL:
5189 perms = SEM__WRITE;
5190 break;
5191 case IPC_RMID:
5192 perms = SEM__DESTROY;
5193 break;
5194 case IPC_SET:
5195 perms = SEM__SETATTR;
5196 break;
5197 case IPC_STAT:
5198 case SEM_STAT:
5199 perms = SEM__GETATTR | SEM__ASSOCIATE;
5200 break;
5201 default:
5202 return 0;
5203 }
5204
5205 err = ipc_has_perm(&sma->sem_perm, perms);
5206 return err;
5207 }
5208
5209 static int selinux_sem_semop(struct sem_array *sma,
5210 struct sembuf *sops, unsigned nsops, int alter)
5211 {
5212 u32 perms;
5213
5214 if (alter)
5215 perms = SEM__READ | SEM__WRITE;
5216 else
5217 perms = SEM__READ;
5218
5219 return ipc_has_perm(&sma->sem_perm, perms);
5220 }
5221
5222 static int selinux_ipc_permission(struct kern_ipc_perm *ipcp, short flag)
5223 {
5224 u32 av = 0;
5225
5226 av = 0;
5227 if (flag & S_IRUGO)
5228 av |= IPC__UNIX_READ;
5229 if (flag & S_IWUGO)
5230 av |= IPC__UNIX_WRITE;
5231
5232 if (av == 0)
5233 return 0;
5234
5235 return ipc_has_perm(ipcp, av);
5236 }
5237
5238 static void selinux_ipc_getsecid(struct kern_ipc_perm *ipcp, u32 *secid)
5239 {
5240 struct ipc_security_struct *isec = ipcp->security;
5241 *secid = isec->sid;
5242 }
5243
5244 static void selinux_d_instantiate(struct dentry *dentry, struct inode *inode)
5245 {
5246 if (inode)
5247 inode_doinit_with_dentry(inode, dentry);
5248 }
5249
5250 static int selinux_getprocattr(struct task_struct *p,
5251 char *name, char **value)
5252 {
5253 const struct task_security_struct *__tsec;
5254 u32 sid;
5255 int error;
5256 unsigned len;
5257
5258 if (current != p) {
5259 error = current_has_perm(p, PROCESS__GETATTR);
5260 if (error)
5261 return error;
5262 }
5263
5264 rcu_read_lock();
5265 __tsec = __task_cred(p)->security;
5266
5267 if (!strcmp(name, "current"))
5268 sid = __tsec->sid;
5269 else if (!strcmp(name, "prev"))
5270 sid = __tsec->osid;
5271 else if (!strcmp(name, "exec"))
5272 sid = __tsec->exec_sid;
5273 else if (!strcmp(name, "fscreate"))
5274 sid = __tsec->create_sid;
5275 else if (!strcmp(name, "keycreate"))
5276 sid = __tsec->keycreate_sid;
5277 else if (!strcmp(name, "sockcreate"))
5278 sid = __tsec->sockcreate_sid;
5279 else
5280 goto invalid;
5281 rcu_read_unlock();
5282
5283 if (!sid)
5284 return 0;
5285
5286 error = security_sid_to_context(sid, value, &len);
5287 if (error)
5288 return error;
5289 return len;
5290
5291 invalid:
5292 rcu_read_unlock();
5293 return -EINVAL;
5294 }
5295
5296 static int selinux_setprocattr(struct task_struct *p,
5297 char *name, void *value, size_t size)
5298 {
5299 struct task_security_struct *tsec;
5300 struct task_struct *tracer;
5301 struct cred *new;
5302 u32 sid = 0, ptsid;
5303 int error;
5304 char *str = value;
5305
5306 if (current != p) {
5307 /* SELinux only allows a process to change its own
5308 security attributes. */
5309 return -EACCES;
5310 }
5311
5312 /*
5313 * Basic control over ability to set these attributes at all.
5314 * current == p, but we'll pass them separately in case the
5315 * above restriction is ever removed.
5316 */
5317 if (!strcmp(name, "exec"))
5318 error = current_has_perm(p, PROCESS__SETEXEC);
5319 else if (!strcmp(name, "fscreate"))
5320 error = current_has_perm(p, PROCESS__SETFSCREATE);
5321 else if (!strcmp(name, "keycreate"))
5322 error = current_has_perm(p, PROCESS__SETKEYCREATE);
5323 else if (!strcmp(name, "sockcreate"))
5324 error = current_has_perm(p, PROCESS__SETSOCKCREATE);
5325 else if (!strcmp(name, "current"))
5326 error = current_has_perm(p, PROCESS__SETCURRENT);
5327 else
5328 error = -EINVAL;
5329 if (error)
5330 return error;
5331
5332 /* Obtain a SID for the context, if one was specified. */
5333 if (size && str[1] && str[1] != '\n') {
5334 if (str[size-1] == '\n') {
5335 str[size-1] = 0;
5336 size--;
5337 }
5338 error = security_context_to_sid(value, size, &sid);
5339 if (error == -EINVAL && !strcmp(name, "fscreate")) {
5340 if (!capable(CAP_MAC_ADMIN)) {
5341 struct audit_buffer *ab;
5342 size_t audit_size;
5343
5344 /* We strip a nul only if it is at the end, otherwise the
5345 * context contains a nul and we should audit that */
5346 if (str[size - 1] == '\0')
5347 audit_size = size - 1;
5348 else
5349 audit_size = size;
5350 ab = audit_log_start(current->audit_context, GFP_ATOMIC, AUDIT_SELINUX_ERR);
5351 audit_log_format(ab, "op=fscreate invalid_context=");
5352 audit_log_n_untrustedstring(ab, value, audit_size);
5353 audit_log_end(ab);
5354
5355 return error;
5356 }
5357 error = security_context_to_sid_force(value, size,
5358 &sid);
5359 }
5360 if (error)
5361 return error;
5362 }
5363
5364 new = prepare_creds();
5365 if (!new)
5366 return -ENOMEM;
5367
5368 /* Permission checking based on the specified context is
5369 performed during the actual operation (execve,
5370 open/mkdir/...), when we know the full context of the
5371 operation. See selinux_bprm_set_creds for the execve
5372 checks and may_create for the file creation checks. The
5373 operation will then fail if the context is not permitted. */
5374 tsec = new->security;
5375 if (!strcmp(name, "exec")) {
5376 tsec->exec_sid = sid;
5377 } else if (!strcmp(name, "fscreate")) {
5378 tsec->create_sid = sid;
5379 } else if (!strcmp(name, "keycreate")) {
5380 error = may_create_key(sid, p);
5381 if (error)
5382 goto abort_change;
5383 tsec->keycreate_sid = sid;
5384 } else if (!strcmp(name, "sockcreate")) {
5385 tsec->sockcreate_sid = sid;
5386 } else if (!strcmp(name, "current")) {
5387 error = -EINVAL;
5388 if (sid == 0)
5389 goto abort_change;
5390
5391 /* Only allow single threaded processes to change context */
5392 error = -EPERM;
5393 if (!current_is_single_threaded()) {
5394 error = security_bounded_transition(tsec->sid, sid);
5395 if (error)
5396 goto abort_change;
5397 }
5398
5399 /* Check permissions for the transition. */
5400 error = avc_has_perm(tsec->sid, sid, SECCLASS_PROCESS,
5401 PROCESS__DYNTRANSITION, NULL);
5402 if (error)
5403 goto abort_change;
5404
5405 /* Check for ptracing, and update the task SID if ok.
5406 Otherwise, leave SID unchanged and fail. */
5407 ptsid = 0;
5408 task_lock(p);
5409 tracer = ptrace_parent(p);
5410 if (tracer)
5411 ptsid = task_sid(tracer);
5412 task_unlock(p);
5413
5414 if (tracer) {
5415 error = avc_has_perm(ptsid, sid, SECCLASS_PROCESS,
5416 PROCESS__PTRACE, NULL);
5417 if (error)
5418 goto abort_change;
5419 }
5420
5421 tsec->sid = sid;
5422 } else {
5423 error = -EINVAL;
5424 goto abort_change;
5425 }
5426
5427 commit_creds(new);
5428 return size;
5429
5430 abort_change:
5431 abort_creds(new);
5432 return error;
5433 }
5434
5435 static int selinux_secid_to_secctx(u32 secid, char **secdata, u32 *seclen)
5436 {
5437 return security_sid_to_context(secid, secdata, seclen);
5438 }
5439
5440 static int selinux_secctx_to_secid(const char *secdata, u32 seclen, u32 *secid)
5441 {
5442 return security_context_to_sid(secdata, seclen, secid);
5443 }
5444
5445 static void selinux_release_secctx(char *secdata, u32 seclen)
5446 {
5447 kfree(secdata);
5448 }
5449
5450 /*
5451 * called with inode->i_mutex locked
5452 */
5453 static int selinux_inode_notifysecctx(struct inode *inode, void *ctx, u32 ctxlen)
5454 {
5455 return selinux_inode_setsecurity(inode, XATTR_SELINUX_SUFFIX, ctx, ctxlen, 0);
5456 }
5457
5458 /*
5459 * called with inode->i_mutex locked
5460 */
5461 static int selinux_inode_setsecctx(struct dentry *dentry, void *ctx, u32 ctxlen)
5462 {
5463 return __vfs_setxattr_noperm(dentry, XATTR_NAME_SELINUX, ctx, ctxlen, 0);
5464 }
5465
5466 static int selinux_inode_getsecctx(struct inode *inode, void **ctx, u32 *ctxlen)
5467 {
5468 int len = 0;
5469 len = selinux_inode_getsecurity(inode, XATTR_SELINUX_SUFFIX,
5470 ctx, true);
5471 if (len < 0)
5472 return len;
5473 *ctxlen = len;
5474 return 0;
5475 }
5476 #ifdef CONFIG_KEYS
5477
5478 static int selinux_key_alloc(struct key *k, const struct cred *cred,
5479 unsigned long flags)
5480 {
5481 const struct task_security_struct *tsec;
5482 struct key_security_struct *ksec;
5483
5484 ksec = kzalloc(sizeof(struct key_security_struct), GFP_KERNEL);
5485 if (!ksec)
5486 return -ENOMEM;
5487
5488 tsec = cred->security;
5489 if (tsec->keycreate_sid)
5490 ksec->sid = tsec->keycreate_sid;
5491 else
5492 ksec->sid = tsec->sid;
5493
5494 k->security = ksec;
5495 return 0;
5496 }
5497
5498 static void selinux_key_free(struct key *k)
5499 {
5500 struct key_security_struct *ksec = k->security;
5501
5502 k->security = NULL;
5503 kfree(ksec);
5504 }
5505
5506 static int selinux_key_permission(key_ref_t key_ref,
5507 const struct cred *cred,
5508 key_perm_t perm)
5509 {
5510 struct key *key;
5511 struct key_security_struct *ksec;
5512 u32 sid;
5513
5514 /* if no specific permissions are requested, we skip the
5515 permission check. No serious, additional covert channels
5516 appear to be created. */
5517 if (perm == 0)
5518 return 0;
5519
5520 sid = cred_sid(cred);
5521
5522 key = key_ref_to_ptr(key_ref);
5523 ksec = key->security;
5524
5525 return avc_has_perm(sid, ksec->sid, SECCLASS_KEY, perm, NULL);
5526 }
5527
5528 static int selinux_key_getsecurity(struct key *key, char **_buffer)
5529 {
5530 struct key_security_struct *ksec = key->security;
5531 char *context = NULL;
5532 unsigned len;
5533 int rc;
5534
5535 rc = security_sid_to_context(ksec->sid, &context, &len);
5536 if (!rc)
5537 rc = len;
5538 *_buffer = context;
5539 return rc;
5540 }
5541
5542 #endif
5543
5544 static struct security_operations selinux_ops = {
5545 .name = "selinux",
5546
5547 .ptrace_access_check = selinux_ptrace_access_check,
5548 .ptrace_traceme = selinux_ptrace_traceme,
5549 .capget = selinux_capget,
5550 .capset = selinux_capset,
5551 .capable = selinux_capable,
5552 .quotactl = selinux_quotactl,
5553 .quota_on = selinux_quota_on,
5554 .syslog = selinux_syslog,
5555 .vm_enough_memory = selinux_vm_enough_memory,
5556
5557 .netlink_send = selinux_netlink_send,
5558
5559 .bprm_set_creds = selinux_bprm_set_creds,
5560 .bprm_committing_creds = selinux_bprm_committing_creds,
5561 .bprm_committed_creds = selinux_bprm_committed_creds,
5562 .bprm_secureexec = selinux_bprm_secureexec,
5563
5564 .sb_alloc_security = selinux_sb_alloc_security,
5565 .sb_free_security = selinux_sb_free_security,
5566 .sb_copy_data = selinux_sb_copy_data,
5567 .sb_remount = selinux_sb_remount,
5568 .sb_kern_mount = selinux_sb_kern_mount,
5569 .sb_show_options = selinux_sb_show_options,
5570 .sb_statfs = selinux_sb_statfs,
5571 .sb_mount = selinux_mount,
5572 .sb_umount = selinux_umount,
5573 .sb_set_mnt_opts = selinux_set_mnt_opts,
5574 .sb_clone_mnt_opts = selinux_sb_clone_mnt_opts,
5575 .sb_parse_opts_str = selinux_parse_opts_str,
5576
5577
5578 .inode_alloc_security = selinux_inode_alloc_security,
5579 .inode_free_security = selinux_inode_free_security,
5580 .inode_init_security = selinux_inode_init_security,
5581 .inode_create = selinux_inode_create,
5582 .inode_link = selinux_inode_link,
5583 .inode_unlink = selinux_inode_unlink,
5584 .inode_symlink = selinux_inode_symlink,
5585 .inode_mkdir = selinux_inode_mkdir,
5586 .inode_rmdir = selinux_inode_rmdir,
5587 .inode_mknod = selinux_inode_mknod,
5588 .inode_rename = selinux_inode_rename,
5589 .inode_readlink = selinux_inode_readlink,
5590 .inode_follow_link = selinux_inode_follow_link,
5591 .inode_permission = selinux_inode_permission,
5592 .inode_setattr = selinux_inode_setattr,
5593 .inode_getattr = selinux_inode_getattr,
5594 .inode_setxattr = selinux_inode_setxattr,
5595 .inode_post_setxattr = selinux_inode_post_setxattr,
5596 .inode_getxattr = selinux_inode_getxattr,
5597 .inode_listxattr = selinux_inode_listxattr,
5598 .inode_removexattr = selinux_inode_removexattr,
5599 .inode_getsecurity = selinux_inode_getsecurity,
5600 .inode_setsecurity = selinux_inode_setsecurity,
5601 .inode_listsecurity = selinux_inode_listsecurity,
5602 .inode_getsecid = selinux_inode_getsecid,
5603
5604 .file_permission = selinux_file_permission,
5605 .file_alloc_security = selinux_file_alloc_security,
5606 .file_free_security = selinux_file_free_security,
5607 .file_ioctl = selinux_file_ioctl,
5608 .mmap_file = selinux_mmap_file,
5609 .mmap_addr = selinux_mmap_addr,
5610 .file_mprotect = selinux_file_mprotect,
5611 .file_lock = selinux_file_lock,
5612 .file_fcntl = selinux_file_fcntl,
5613 .file_set_fowner = selinux_file_set_fowner,
5614 .file_send_sigiotask = selinux_file_send_sigiotask,
5615 .file_receive = selinux_file_receive,
5616
5617 .file_open = selinux_file_open,
5618
5619 .task_create = selinux_task_create,
5620 .cred_alloc_blank = selinux_cred_alloc_blank,
5621 .cred_free = selinux_cred_free,
5622 .cred_prepare = selinux_cred_prepare,
5623 .cred_transfer = selinux_cred_transfer,
5624 .kernel_act_as = selinux_kernel_act_as,
5625 .kernel_create_files_as = selinux_kernel_create_files_as,
5626 .kernel_module_request = selinux_kernel_module_request,
5627 .task_setpgid = selinux_task_setpgid,
5628 .task_getpgid = selinux_task_getpgid,
5629 .task_getsid = selinux_task_getsid,
5630 .task_getsecid = selinux_task_getsecid,
5631 .task_setnice = selinux_task_setnice,
5632 .task_setioprio = selinux_task_setioprio,
5633 .task_getioprio = selinux_task_getioprio,
5634 .task_setrlimit = selinux_task_setrlimit,
5635 .task_setscheduler = selinux_task_setscheduler,
5636 .task_getscheduler = selinux_task_getscheduler,
5637 .task_movememory = selinux_task_movememory,
5638 .task_kill = selinux_task_kill,
5639 .task_wait = selinux_task_wait,
5640 .task_to_inode = selinux_task_to_inode,
5641
5642 .ipc_permission = selinux_ipc_permission,
5643 .ipc_getsecid = selinux_ipc_getsecid,
5644
5645 .msg_msg_alloc_security = selinux_msg_msg_alloc_security,
5646 .msg_msg_free_security = selinux_msg_msg_free_security,
5647
5648 .msg_queue_alloc_security = selinux_msg_queue_alloc_security,
5649 .msg_queue_free_security = selinux_msg_queue_free_security,
5650 .msg_queue_associate = selinux_msg_queue_associate,
5651 .msg_queue_msgctl = selinux_msg_queue_msgctl,
5652 .msg_queue_msgsnd = selinux_msg_queue_msgsnd,
5653 .msg_queue_msgrcv = selinux_msg_queue_msgrcv,
5654
5655 .shm_alloc_security = selinux_shm_alloc_security,
5656 .shm_free_security = selinux_shm_free_security,
5657 .shm_associate = selinux_shm_associate,
5658 .shm_shmctl = selinux_shm_shmctl,
5659 .shm_shmat = selinux_shm_shmat,
5660
5661 .sem_alloc_security = selinux_sem_alloc_security,
5662 .sem_free_security = selinux_sem_free_security,
5663 .sem_associate = selinux_sem_associate,
5664 .sem_semctl = selinux_sem_semctl,
5665 .sem_semop = selinux_sem_semop,
5666
5667 .d_instantiate = selinux_d_instantiate,
5668
5669 .getprocattr = selinux_getprocattr,
5670 .setprocattr = selinux_setprocattr,
5671
5672 .secid_to_secctx = selinux_secid_to_secctx,
5673 .secctx_to_secid = selinux_secctx_to_secid,
5674 .release_secctx = selinux_release_secctx,
5675 .inode_notifysecctx = selinux_inode_notifysecctx,
5676 .inode_setsecctx = selinux_inode_setsecctx,
5677 .inode_getsecctx = selinux_inode_getsecctx,
5678
5679 .unix_stream_connect = selinux_socket_unix_stream_connect,
5680 .unix_may_send = selinux_socket_unix_may_send,
5681
5682 .socket_create = selinux_socket_create,
5683 .socket_post_create = selinux_socket_post_create,
5684 .socket_bind = selinux_socket_bind,
5685 .socket_connect = selinux_socket_connect,
5686 .socket_listen = selinux_socket_listen,
5687 .socket_accept = selinux_socket_accept,
5688 .socket_sendmsg = selinux_socket_sendmsg,
5689 .socket_recvmsg = selinux_socket_recvmsg,
5690 .socket_getsockname = selinux_socket_getsockname,
5691 .socket_getpeername = selinux_socket_getpeername,
5692 .socket_getsockopt = selinux_socket_getsockopt,
5693 .socket_setsockopt = selinux_socket_setsockopt,
5694 .socket_shutdown = selinux_socket_shutdown,
5695 .socket_sock_rcv_skb = selinux_socket_sock_rcv_skb,
5696 .socket_getpeersec_stream = selinux_socket_getpeersec_stream,
5697 .socket_getpeersec_dgram = selinux_socket_getpeersec_dgram,
5698 .sk_alloc_security = selinux_sk_alloc_security,
5699 .sk_free_security = selinux_sk_free_security,
5700 .sk_clone_security = selinux_sk_clone_security,
5701 .sk_getsecid = selinux_sk_getsecid,
5702 .sock_graft = selinux_sock_graft,
5703 .inet_conn_request = selinux_inet_conn_request,
5704 .inet_csk_clone = selinux_inet_csk_clone,
5705 .inet_conn_established = selinux_inet_conn_established,
5706 .secmark_relabel_packet = selinux_secmark_relabel_packet,
5707 .secmark_refcount_inc = selinux_secmark_refcount_inc,
5708 .secmark_refcount_dec = selinux_secmark_refcount_dec,
5709 .req_classify_flow = selinux_req_classify_flow,
5710 .tun_dev_alloc_security = selinux_tun_dev_alloc_security,
5711 .tun_dev_free_security = selinux_tun_dev_free_security,
5712 .tun_dev_create = selinux_tun_dev_create,
5713 .tun_dev_attach_queue = selinux_tun_dev_attach_queue,
5714 .tun_dev_attach = selinux_tun_dev_attach,
5715 .tun_dev_open = selinux_tun_dev_open,
5716 .skb_owned_by = selinux_skb_owned_by,
5717
5718 #ifdef CONFIG_SECURITY_NETWORK_XFRM
5719 .xfrm_policy_alloc_security = selinux_xfrm_policy_alloc,
5720 .xfrm_policy_clone_security = selinux_xfrm_policy_clone,
5721 .xfrm_policy_free_security = selinux_xfrm_policy_free,
5722 .xfrm_policy_delete_security = selinux_xfrm_policy_delete,
5723 .xfrm_state_alloc_security = selinux_xfrm_state_alloc,
5724 .xfrm_state_free_security = selinux_xfrm_state_free,
5725 .xfrm_state_delete_security = selinux_xfrm_state_delete,
5726 .xfrm_policy_lookup = selinux_xfrm_policy_lookup,
5727 .xfrm_state_pol_flow_match = selinux_xfrm_state_pol_flow_match,
5728 .xfrm_decode_session = selinux_xfrm_decode_session,
5729 #endif
5730
5731 #ifdef CONFIG_KEYS
5732 .key_alloc = selinux_key_alloc,
5733 .key_free = selinux_key_free,
5734 .key_permission = selinux_key_permission,
5735 .key_getsecurity = selinux_key_getsecurity,
5736 #endif
5737
5738 #ifdef CONFIG_AUDIT
5739 .audit_rule_init = selinux_audit_rule_init,
5740 .audit_rule_known = selinux_audit_rule_known,
5741 .audit_rule_match = selinux_audit_rule_match,
5742 .audit_rule_free = selinux_audit_rule_free,
5743 #endif
5744 };
5745
5746 static __init int selinux_init(void)
5747 {
5748 if (!security_module_enable(&selinux_ops)) {
5749 selinux_enabled = 0;
5750 return 0;
5751 }
5752
5753 if (!selinux_enabled) {
5754 printk(KERN_INFO "SELinux: Disabled at boot.\n");
5755 return 0;
5756 }
5757
5758 printk(KERN_INFO "SELinux: Initializing.\n");
5759
5760 /* Set the security state for the initial task. */
5761 cred_init_security();
5762
5763 default_noexec = !(VM_DATA_DEFAULT_FLAGS & VM_EXEC);
5764
5765 sel_inode_cache = kmem_cache_create("selinux_inode_security",
5766 sizeof(struct inode_security_struct),
5767 0, SLAB_PANIC, NULL);
5768 avc_init();
5769
5770 if (register_security(&selinux_ops))
5771 panic("SELinux: Unable to register with kernel.\n");
5772
5773 if (selinux_enforcing)
5774 printk(KERN_DEBUG "SELinux: Starting in enforcing mode\n");
5775 else
5776 printk(KERN_DEBUG "SELinux: Starting in permissive mode\n");
5777
5778 return 0;
5779 }
5780
5781 static void delayed_superblock_init(struct super_block *sb, void *unused)
5782 {
5783 superblock_doinit(sb, NULL);
5784 }
5785
5786 void selinux_complete_init(void)
5787 {
5788 printk(KERN_DEBUG "SELinux: Completing initialization.\n");
5789
5790 /* Set up any superblocks initialized prior to the policy load. */
5791 printk(KERN_DEBUG "SELinux: Setting up existing superblocks.\n");
5792 iterate_supers(delayed_superblock_init, NULL);
5793 }
5794
5795 /* SELinux requires early initialization in order to label
5796 all processes and objects when they are created. */
5797 security_initcall(selinux_init);
5798
5799 #if defined(CONFIG_NETFILTER)
5800
5801 static struct nf_hook_ops selinux_ipv4_ops[] = {
5802 {
5803 .hook = selinux_ipv4_postroute,
5804 .owner = THIS_MODULE,
5805 .pf = NFPROTO_IPV4,
5806 .hooknum = NF_INET_POST_ROUTING,
5807 .priority = NF_IP_PRI_SELINUX_LAST,
5808 },
5809 {
5810 .hook = selinux_ipv4_forward,
5811 .owner = THIS_MODULE,
5812 .pf = NFPROTO_IPV4,
5813 .hooknum = NF_INET_FORWARD,
5814 .priority = NF_IP_PRI_SELINUX_FIRST,
5815 },
5816 {
5817 .hook = selinux_ipv4_output,
5818 .owner = THIS_MODULE,
5819 .pf = NFPROTO_IPV4,
5820 .hooknum = NF_INET_LOCAL_OUT,
5821 .priority = NF_IP_PRI_SELINUX_FIRST,
5822 }
5823 };
5824
5825 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
5826
5827 static struct nf_hook_ops selinux_ipv6_ops[] = {
5828 {
5829 .hook = selinux_ipv6_postroute,
5830 .owner = THIS_MODULE,
5831 .pf = NFPROTO_IPV6,
5832 .hooknum = NF_INET_POST_ROUTING,
5833 .priority = NF_IP6_PRI_SELINUX_LAST,
5834 },
5835 {
5836 .hook = selinux_ipv6_forward,
5837 .owner = THIS_MODULE,
5838 .pf = NFPROTO_IPV6,
5839 .hooknum = NF_INET_FORWARD,
5840 .priority = NF_IP6_PRI_SELINUX_FIRST,
5841 }
5842 };
5843
5844 #endif /* IPV6 */
5845
5846 static int __init selinux_nf_ip_init(void)
5847 {
5848 int err = 0;
5849
5850 if (!selinux_enabled)
5851 goto out;
5852
5853 printk(KERN_DEBUG "SELinux: Registering netfilter hooks\n");
5854
5855 err = nf_register_hooks(selinux_ipv4_ops, ARRAY_SIZE(selinux_ipv4_ops));
5856 if (err)
5857 panic("SELinux: nf_register_hooks for IPv4: error %d\n", err);
5858
5859 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
5860 err = nf_register_hooks(selinux_ipv6_ops, ARRAY_SIZE(selinux_ipv6_ops));
5861 if (err)
5862 panic("SELinux: nf_register_hooks for IPv6: error %d\n", err);
5863 #endif /* IPV6 */
5864
5865 out:
5866 return err;
5867 }
5868
5869 __initcall(selinux_nf_ip_init);
5870
5871 #ifdef CONFIG_SECURITY_SELINUX_DISABLE
5872 static void selinux_nf_ip_exit(void)
5873 {
5874 printk(KERN_DEBUG "SELinux: Unregistering netfilter hooks\n");
5875
5876 nf_unregister_hooks(selinux_ipv4_ops, ARRAY_SIZE(selinux_ipv4_ops));
5877 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
5878 nf_unregister_hooks(selinux_ipv6_ops, ARRAY_SIZE(selinux_ipv6_ops));
5879 #endif /* IPV6 */
5880 }
5881 #endif
5882
5883 #else /* CONFIG_NETFILTER */
5884
5885 #ifdef CONFIG_SECURITY_SELINUX_DISABLE
5886 #define selinux_nf_ip_exit()
5887 #endif
5888
5889 #endif /* CONFIG_NETFILTER */
5890
5891 #ifdef CONFIG_SECURITY_SELINUX_DISABLE
5892 static int selinux_disabled;
5893
5894 int selinux_disable(void)
5895 {
5896 if (ss_initialized) {
5897 /* Not permitted after initial policy load. */
5898 return -EINVAL;
5899 }
5900
5901 if (selinux_disabled) {
5902 /* Only do this once. */
5903 return -EINVAL;
5904 }
5905
5906 printk(KERN_INFO "SELinux: Disabled at runtime.\n");
5907
5908 selinux_disabled = 1;
5909 selinux_enabled = 0;
5910
5911 reset_security_ops();
5912
5913 /* Try to destroy the avc node cache */
5914 avc_disable();
5915
5916 /* Unregister netfilter hooks. */
5917 selinux_nf_ip_exit();
5918
5919 /* Unregister selinuxfs. */
5920 exit_sel_fs();
5921
5922 return 0;
5923 }
5924 #endif
Linus' kernel tree