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Security: Add hook to calculate context based on a negative dentry.
[mirror_ubuntu-bionic-kernel.git] / security / selinux / hooks.c
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 /* Check whether a task can use an open file descriptor to
1551 access an inode in a given way. Check access to the
1552 descriptor itself, and then use dentry_has_perm to
1553 check a particular permission to the file.
1554 Access to the descriptor is implicitly granted if it
1555 has the same SID as the process. If av is zero, then
1556 access to the file is not checked, e.g. for cases
1557 where only the descriptor is affected like seek. */
1558 static int file_has_perm(const struct cred *cred,
1559 struct file *file,
1560 u32 av)
1561 {
1562 struct file_security_struct *fsec = file->f_security;
1563 struct inode *inode = file_inode(file);
1564 struct common_audit_data ad;
1565 u32 sid = cred_sid(cred);
1566 int rc;
1567
1568 ad.type = LSM_AUDIT_DATA_PATH;
1569 ad.u.path = file->f_path;
1570
1571 if (sid != fsec->sid) {
1572 rc = avc_has_perm(sid, fsec->sid,
1573 SECCLASS_FD,
1574 FD__USE,
1575 &ad);
1576 if (rc)
1577 goto out;
1578 }
1579
1580 /* av is zero if only checking access to the descriptor. */
1581 rc = 0;
1582 if (av)
1583 rc = inode_has_perm(cred, inode, av, &ad, 0);
1584
1585 out:
1586 return rc;
1587 }
1588
1589 /* Check whether a task can create a file. */
1590 static int may_create(struct inode *dir,
1591 struct dentry *dentry,
1592 u16 tclass)
1593 {
1594 const struct task_security_struct *tsec = current_security();
1595 struct inode_security_struct *dsec;
1596 struct superblock_security_struct *sbsec;
1597 u32 sid, newsid;
1598 struct common_audit_data ad;
1599 int rc;
1600
1601 dsec = dir->i_security;
1602 sbsec = dir->i_sb->s_security;
1603
1604 sid = tsec->sid;
1605 newsid = tsec->create_sid;
1606
1607 ad.type = LSM_AUDIT_DATA_DENTRY;
1608 ad.u.dentry = dentry;
1609
1610 rc = avc_has_perm(sid, dsec->sid, SECCLASS_DIR,
1611 DIR__ADD_NAME | DIR__SEARCH,
1612 &ad);
1613 if (rc)
1614 return rc;
1615
1616 if (!newsid || !(sbsec->flags & SE_SBLABELSUPP)) {
1617 rc = security_transition_sid(sid, dsec->sid, tclass,
1618 &dentry->d_name, &newsid);
1619 if (rc)
1620 return rc;
1621 }
1622
1623 rc = avc_has_perm(sid, newsid, tclass, FILE__CREATE, &ad);
1624 if (rc)
1625 return rc;
1626
1627 return avc_has_perm(newsid, sbsec->sid,
1628 SECCLASS_FILESYSTEM,
1629 FILESYSTEM__ASSOCIATE, &ad);
1630 }
1631
1632 /* Check whether a task can create a key. */
1633 static int may_create_key(u32 ksid,
1634 struct task_struct *ctx)
1635 {
1636 u32 sid = task_sid(ctx);
1637
1638 return avc_has_perm(sid, ksid, SECCLASS_KEY, KEY__CREATE, NULL);
1639 }
1640
1641 #define MAY_LINK 0
1642 #define MAY_UNLINK 1
1643 #define MAY_RMDIR 2
1644
1645 /* Check whether a task can link, unlink, or rmdir a file/directory. */
1646 static int may_link(struct inode *dir,
1647 struct dentry *dentry,
1648 int kind)
1649
1650 {
1651 struct inode_security_struct *dsec, *isec;
1652 struct common_audit_data ad;
1653 u32 sid = current_sid();
1654 u32 av;
1655 int rc;
1656
1657 dsec = dir->i_security;
1658 isec = dentry->d_inode->i_security;
1659
1660 ad.type = LSM_AUDIT_DATA_DENTRY;
1661 ad.u.dentry = dentry;
1662
1663 av = DIR__SEARCH;
1664 av |= (kind ? DIR__REMOVE_NAME : DIR__ADD_NAME);
1665 rc = avc_has_perm(sid, dsec->sid, SECCLASS_DIR, av, &ad);
1666 if (rc)
1667 return rc;
1668
1669 switch (kind) {
1670 case MAY_LINK:
1671 av = FILE__LINK;
1672 break;
1673 case MAY_UNLINK:
1674 av = FILE__UNLINK;
1675 break;
1676 case MAY_RMDIR:
1677 av = DIR__RMDIR;
1678 break;
1679 default:
1680 printk(KERN_WARNING "SELinux: %s: unrecognized kind %d\n",
1681 __func__, kind);
1682 return 0;
1683 }
1684
1685 rc = avc_has_perm(sid, isec->sid, isec->sclass, av, &ad);
1686 return rc;
1687 }
1688
1689 static inline int may_rename(struct inode *old_dir,
1690 struct dentry *old_dentry,
1691 struct inode *new_dir,
1692 struct dentry *new_dentry)
1693 {
1694 struct inode_security_struct *old_dsec, *new_dsec, *old_isec, *new_isec;
1695 struct common_audit_data ad;
1696 u32 sid = current_sid();
1697 u32 av;
1698 int old_is_dir, new_is_dir;
1699 int rc;
1700
1701 old_dsec = old_dir->i_security;
1702 old_isec = old_dentry->d_inode->i_security;
1703 old_is_dir = S_ISDIR(old_dentry->d_inode->i_mode);
1704 new_dsec = new_dir->i_security;
1705
1706 ad.type = LSM_AUDIT_DATA_DENTRY;
1707
1708 ad.u.dentry = old_dentry;
1709 rc = avc_has_perm(sid, old_dsec->sid, SECCLASS_DIR,
1710 DIR__REMOVE_NAME | DIR__SEARCH, &ad);
1711 if (rc)
1712 return rc;
1713 rc = avc_has_perm(sid, old_isec->sid,
1714 old_isec->sclass, FILE__RENAME, &ad);
1715 if (rc)
1716 return rc;
1717 if (old_is_dir && new_dir != old_dir) {
1718 rc = avc_has_perm(sid, old_isec->sid,
1719 old_isec->sclass, DIR__REPARENT, &ad);
1720 if (rc)
1721 return rc;
1722 }
1723
1724 ad.u.dentry = new_dentry;
1725 av = DIR__ADD_NAME | DIR__SEARCH;
1726 if (new_dentry->d_inode)
1727 av |= DIR__REMOVE_NAME;
1728 rc = avc_has_perm(sid, new_dsec->sid, SECCLASS_DIR, av, &ad);
1729 if (rc)
1730 return rc;
1731 if (new_dentry->d_inode) {
1732 new_isec = new_dentry->d_inode->i_security;
1733 new_is_dir = S_ISDIR(new_dentry->d_inode->i_mode);
1734 rc = avc_has_perm(sid, new_isec->sid,
1735 new_isec->sclass,
1736 (new_is_dir ? DIR__RMDIR : FILE__UNLINK), &ad);
1737 if (rc)
1738 return rc;
1739 }
1740
1741 return 0;
1742 }
1743
1744 /* Check whether a task can perform a filesystem operation. */
1745 static int superblock_has_perm(const struct cred *cred,
1746 struct super_block *sb,
1747 u32 perms,
1748 struct common_audit_data *ad)
1749 {
1750 struct superblock_security_struct *sbsec;
1751 u32 sid = cred_sid(cred);
1752
1753 sbsec = sb->s_security;
1754 return avc_has_perm(sid, sbsec->sid, SECCLASS_FILESYSTEM, perms, ad);
1755 }
1756
1757 /* Convert a Linux mode and permission mask to an access vector. */
1758 static inline u32 file_mask_to_av(int mode, int mask)
1759 {
1760 u32 av = 0;
1761
1762 if (!S_ISDIR(mode)) {
1763 if (mask & MAY_EXEC)
1764 av |= FILE__EXECUTE;
1765 if (mask & MAY_READ)
1766 av |= FILE__READ;
1767
1768 if (mask & MAY_APPEND)
1769 av |= FILE__APPEND;
1770 else if (mask & MAY_WRITE)
1771 av |= FILE__WRITE;
1772
1773 } else {
1774 if (mask & MAY_EXEC)
1775 av |= DIR__SEARCH;
1776 if (mask & MAY_WRITE)
1777 av |= DIR__WRITE;
1778 if (mask & MAY_READ)
1779 av |= DIR__READ;
1780 }
1781
1782 return av;
1783 }
1784
1785 /* Convert a Linux file to an access vector. */
1786 static inline u32 file_to_av(struct file *file)
1787 {
1788 u32 av = 0;
1789
1790 if (file->f_mode & FMODE_READ)
1791 av |= FILE__READ;
1792 if (file->f_mode & FMODE_WRITE) {
1793 if (file->f_flags & O_APPEND)
1794 av |= FILE__APPEND;
1795 else
1796 av |= FILE__WRITE;
1797 }
1798 if (!av) {
1799 /*
1800 * Special file opened with flags 3 for ioctl-only use.
1801 */
1802 av = FILE__IOCTL;
1803 }
1804
1805 return av;
1806 }
1807
1808 /*
1809 * Convert a file to an access vector and include the correct open
1810 * open permission.
1811 */
1812 static inline u32 open_file_to_av(struct file *file)
1813 {
1814 u32 av = file_to_av(file);
1815
1816 if (selinux_policycap_openperm)
1817 av |= FILE__OPEN;
1818
1819 return av;
1820 }
1821
1822 /* Hook functions begin here. */
1823
1824 static int selinux_ptrace_access_check(struct task_struct *child,
1825 unsigned int mode)
1826 {
1827 int rc;
1828
1829 rc = cap_ptrace_access_check(child, mode);
1830 if (rc)
1831 return rc;
1832
1833 if (mode & PTRACE_MODE_READ) {
1834 u32 sid = current_sid();
1835 u32 csid = task_sid(child);
1836 return avc_has_perm(sid, csid, SECCLASS_FILE, FILE__READ, NULL);
1837 }
1838
1839 return current_has_perm(child, PROCESS__PTRACE);
1840 }
1841
1842 static int selinux_ptrace_traceme(struct task_struct *parent)
1843 {
1844 int rc;
1845
1846 rc = cap_ptrace_traceme(parent);
1847 if (rc)
1848 return rc;
1849
1850 return task_has_perm(parent, current, PROCESS__PTRACE);
1851 }
1852
1853 static int selinux_capget(struct task_struct *target, kernel_cap_t *effective,
1854 kernel_cap_t *inheritable, kernel_cap_t *permitted)
1855 {
1856 int error;
1857
1858 error = current_has_perm(target, PROCESS__GETCAP);
1859 if (error)
1860 return error;
1861
1862 return cap_capget(target, effective, inheritable, permitted);
1863 }
1864
1865 static int selinux_capset(struct cred *new, const struct cred *old,
1866 const kernel_cap_t *effective,
1867 const kernel_cap_t *inheritable,
1868 const kernel_cap_t *permitted)
1869 {
1870 int error;
1871
1872 error = cap_capset(new, old,
1873 effective, inheritable, permitted);
1874 if (error)
1875 return error;
1876
1877 return cred_has_perm(old, new, PROCESS__SETCAP);
1878 }
1879
1880 /*
1881 * (This comment used to live with the selinux_task_setuid hook,
1882 * which was removed).
1883 *
1884 * Since setuid only affects the current process, and since the SELinux
1885 * controls are not based on the Linux identity attributes, SELinux does not
1886 * need to control this operation. However, SELinux does control the use of
1887 * the CAP_SETUID and CAP_SETGID capabilities using the capable hook.
1888 */
1889
1890 static int selinux_capable(const struct cred *cred, struct user_namespace *ns,
1891 int cap, int audit)
1892 {
1893 int rc;
1894
1895 rc = cap_capable(cred, ns, cap, audit);
1896 if (rc)
1897 return rc;
1898
1899 return cred_has_capability(cred, cap, audit);
1900 }
1901
1902 static int selinux_quotactl(int cmds, int type, int id, struct super_block *sb)
1903 {
1904 const struct cred *cred = current_cred();
1905 int rc = 0;
1906
1907 if (!sb)
1908 return 0;
1909
1910 switch (cmds) {
1911 case Q_SYNC:
1912 case Q_QUOTAON:
1913 case Q_QUOTAOFF:
1914 case Q_SETINFO:
1915 case Q_SETQUOTA:
1916 rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAMOD, NULL);
1917 break;
1918 case Q_GETFMT:
1919 case Q_GETINFO:
1920 case Q_GETQUOTA:
1921 rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAGET, NULL);
1922 break;
1923 default:
1924 rc = 0; /* let the kernel handle invalid cmds */
1925 break;
1926 }
1927 return rc;
1928 }
1929
1930 static int selinux_quota_on(struct dentry *dentry)
1931 {
1932 const struct cred *cred = current_cred();
1933
1934 return dentry_has_perm(cred, dentry, FILE__QUOTAON);
1935 }
1936
1937 static int selinux_syslog(int type)
1938 {
1939 int rc;
1940
1941 switch (type) {
1942 case SYSLOG_ACTION_READ_ALL: /* Read last kernel messages */
1943 case SYSLOG_ACTION_SIZE_BUFFER: /* Return size of the log buffer */
1944 rc = task_has_system(current, SYSTEM__SYSLOG_READ);
1945 break;
1946 case SYSLOG_ACTION_CONSOLE_OFF: /* Disable logging to console */
1947 case SYSLOG_ACTION_CONSOLE_ON: /* Enable logging to console */
1948 /* Set level of messages printed to console */
1949 case SYSLOG_ACTION_CONSOLE_LEVEL:
1950 rc = task_has_system(current, SYSTEM__SYSLOG_CONSOLE);
1951 break;
1952 case SYSLOG_ACTION_CLOSE: /* Close log */
1953 case SYSLOG_ACTION_OPEN: /* Open log */
1954 case SYSLOG_ACTION_READ: /* Read from log */
1955 case SYSLOG_ACTION_READ_CLEAR: /* Read/clear last kernel messages */
1956 case SYSLOG_ACTION_CLEAR: /* Clear ring buffer */
1957 default:
1958 rc = task_has_system(current, SYSTEM__SYSLOG_MOD);
1959 break;
1960 }
1961 return rc;
1962 }
1963
1964 /*
1965 * Check that a process has enough memory to allocate a new virtual
1966 * mapping. 0 means there is enough memory for the allocation to
1967 * succeed and -ENOMEM implies there is not.
1968 *
1969 * Do not audit the selinux permission check, as this is applied to all
1970 * processes that allocate mappings.
1971 */
1972 static int selinux_vm_enough_memory(struct mm_struct *mm, long pages)
1973 {
1974 int rc, cap_sys_admin = 0;
1975
1976 rc = selinux_capable(current_cred(), &init_user_ns, CAP_SYS_ADMIN,
1977 SECURITY_CAP_NOAUDIT);
1978 if (rc == 0)
1979 cap_sys_admin = 1;
1980
1981 return __vm_enough_memory(mm, pages, cap_sys_admin);
1982 }
1983
1984 /* binprm security operations */
1985
1986 static int selinux_bprm_set_creds(struct linux_binprm *bprm)
1987 {
1988 const struct task_security_struct *old_tsec;
1989 struct task_security_struct *new_tsec;
1990 struct inode_security_struct *isec;
1991 struct common_audit_data ad;
1992 struct inode *inode = file_inode(bprm->file);
1993 int rc;
1994
1995 rc = cap_bprm_set_creds(bprm);
1996 if (rc)
1997 return rc;
1998
1999 /* SELinux context only depends on initial program or script and not
2000 * the script interpreter */
2001 if (bprm->cred_prepared)
2002 return 0;
2003
2004 old_tsec = current_security();
2005 new_tsec = bprm->cred->security;
2006 isec = inode->i_security;
2007
2008 /* Default to the current task SID. */
2009 new_tsec->sid = old_tsec->sid;
2010 new_tsec->osid = old_tsec->sid;
2011
2012 /* Reset fs, key, and sock SIDs on execve. */
2013 new_tsec->create_sid = 0;
2014 new_tsec->keycreate_sid = 0;
2015 new_tsec->sockcreate_sid = 0;
2016
2017 if (old_tsec->exec_sid) {
2018 new_tsec->sid = old_tsec->exec_sid;
2019 /* Reset exec SID on execve. */
2020 new_tsec->exec_sid = 0;
2021
2022 /*
2023 * Minimize confusion: if no_new_privs and a transition is
2024 * explicitly requested, then fail the exec.
2025 */
2026 if (bprm->unsafe & LSM_UNSAFE_NO_NEW_PRIVS)
2027 return -EPERM;
2028 } else {
2029 /* Check for a default transition on this program. */
2030 rc = security_transition_sid(old_tsec->sid, isec->sid,
2031 SECCLASS_PROCESS, NULL,
2032 &new_tsec->sid);
2033 if (rc)
2034 return rc;
2035 }
2036
2037 ad.type = LSM_AUDIT_DATA_PATH;
2038 ad.u.path = bprm->file->f_path;
2039
2040 if ((bprm->file->f_path.mnt->mnt_flags & MNT_NOSUID) ||
2041 (bprm->unsafe & LSM_UNSAFE_NO_NEW_PRIVS))
2042 new_tsec->sid = old_tsec->sid;
2043
2044 if (new_tsec->sid == old_tsec->sid) {
2045 rc = avc_has_perm(old_tsec->sid, isec->sid,
2046 SECCLASS_FILE, FILE__EXECUTE_NO_TRANS, &ad);
2047 if (rc)
2048 return rc;
2049 } else {
2050 /* Check permissions for the transition. */
2051 rc = avc_has_perm(old_tsec->sid, new_tsec->sid,
2052 SECCLASS_PROCESS, PROCESS__TRANSITION, &ad);
2053 if (rc)
2054 return rc;
2055
2056 rc = avc_has_perm(new_tsec->sid, isec->sid,
2057 SECCLASS_FILE, FILE__ENTRYPOINT, &ad);
2058 if (rc)
2059 return rc;
2060
2061 /* Check for shared state */
2062 if (bprm->unsafe & LSM_UNSAFE_SHARE) {
2063 rc = avc_has_perm(old_tsec->sid, new_tsec->sid,
2064 SECCLASS_PROCESS, PROCESS__SHARE,
2065 NULL);
2066 if (rc)
2067 return -EPERM;
2068 }
2069
2070 /* Make sure that anyone attempting to ptrace over a task that
2071 * changes its SID has the appropriate permit */
2072 if (bprm->unsafe &
2073 (LSM_UNSAFE_PTRACE | LSM_UNSAFE_PTRACE_CAP)) {
2074 struct task_struct *tracer;
2075 struct task_security_struct *sec;
2076 u32 ptsid = 0;
2077
2078 rcu_read_lock();
2079 tracer = ptrace_parent(current);
2080 if (likely(tracer != NULL)) {
2081 sec = __task_cred(tracer)->security;
2082 ptsid = sec->sid;
2083 }
2084 rcu_read_unlock();
2085
2086 if (ptsid != 0) {
2087 rc = avc_has_perm(ptsid, new_tsec->sid,
2088 SECCLASS_PROCESS,
2089 PROCESS__PTRACE, NULL);
2090 if (rc)
2091 return -EPERM;
2092 }
2093 }
2094
2095 /* Clear any possibly unsafe personality bits on exec: */
2096 bprm->per_clear |= PER_CLEAR_ON_SETID;
2097 }
2098
2099 return 0;
2100 }
2101
2102 static int selinux_bprm_secureexec(struct linux_binprm *bprm)
2103 {
2104 const struct task_security_struct *tsec = current_security();
2105 u32 sid, osid;
2106 int atsecure = 0;
2107
2108 sid = tsec->sid;
2109 osid = tsec->osid;
2110
2111 if (osid != sid) {
2112 /* Enable secure mode for SIDs transitions unless
2113 the noatsecure permission is granted between
2114 the two SIDs, i.e. ahp returns 0. */
2115 atsecure = avc_has_perm(osid, sid,
2116 SECCLASS_PROCESS,
2117 PROCESS__NOATSECURE, NULL);
2118 }
2119
2120 return (atsecure || cap_bprm_secureexec(bprm));
2121 }
2122
2123 static int match_file(const void *p, struct file *file, unsigned fd)
2124 {
2125 return file_has_perm(p, file, file_to_av(file)) ? fd + 1 : 0;
2126 }
2127
2128 /* Derived from fs/exec.c:flush_old_files. */
2129 static inline void flush_unauthorized_files(const struct cred *cred,
2130 struct files_struct *files)
2131 {
2132 struct file *file, *devnull = NULL;
2133 struct tty_struct *tty;
2134 int drop_tty = 0;
2135 unsigned n;
2136
2137 tty = get_current_tty();
2138 if (tty) {
2139 spin_lock(&tty_files_lock);
2140 if (!list_empty(&tty->tty_files)) {
2141 struct tty_file_private *file_priv;
2142
2143 /* Revalidate access to controlling tty.
2144 Use path_has_perm on the tty path directly rather
2145 than using file_has_perm, as this particular open
2146 file may belong to another process and we are only
2147 interested in the inode-based check here. */
2148 file_priv = list_first_entry(&tty->tty_files,
2149 struct tty_file_private, list);
2150 file = file_priv->file;
2151 if (path_has_perm(cred, &file->f_path, FILE__READ | FILE__WRITE))
2152 drop_tty = 1;
2153 }
2154 spin_unlock(&tty_files_lock);
2155 tty_kref_put(tty);
2156 }
2157 /* Reset controlling tty. */
2158 if (drop_tty)
2159 no_tty();
2160
2161 /* Revalidate access to inherited open files. */
2162 n = iterate_fd(files, 0, match_file, cred);
2163 if (!n) /* none found? */
2164 return;
2165
2166 devnull = dentry_open(&selinux_null, O_RDWR, cred);
2167 if (IS_ERR(devnull))
2168 devnull = NULL;
2169 /* replace all the matching ones with this */
2170 do {
2171 replace_fd(n - 1, devnull, 0);
2172 } while ((n = iterate_fd(files, n, match_file, cred)) != 0);
2173 if (devnull)
2174 fput(devnull);
2175 }
2176
2177 /*
2178 * Prepare a process for imminent new credential changes due to exec
2179 */
2180 static void selinux_bprm_committing_creds(struct linux_binprm *bprm)
2181 {
2182 struct task_security_struct *new_tsec;
2183 struct rlimit *rlim, *initrlim;
2184 int rc, i;
2185
2186 new_tsec = bprm->cred->security;
2187 if (new_tsec->sid == new_tsec->osid)
2188 return;
2189
2190 /* Close files for which the new task SID is not authorized. */
2191 flush_unauthorized_files(bprm->cred, current->files);
2192
2193 /* Always clear parent death signal on SID transitions. */
2194 current->pdeath_signal = 0;
2195
2196 /* Check whether the new SID can inherit resource limits from the old
2197 * SID. If not, reset all soft limits to the lower of the current
2198 * task's hard limit and the init task's soft limit.
2199 *
2200 * Note that the setting of hard limits (even to lower them) can be
2201 * controlled by the setrlimit check. The inclusion of the init task's
2202 * soft limit into the computation is to avoid resetting soft limits
2203 * higher than the default soft limit for cases where the default is
2204 * lower than the hard limit, e.g. RLIMIT_CORE or RLIMIT_STACK.
2205 */
2206 rc = avc_has_perm(new_tsec->osid, new_tsec->sid, SECCLASS_PROCESS,
2207 PROCESS__RLIMITINH, NULL);
2208 if (rc) {
2209 /* protect against do_prlimit() */
2210 task_lock(current);
2211 for (i = 0; i < RLIM_NLIMITS; i++) {
2212 rlim = current->signal->rlim + i;
2213 initrlim = init_task.signal->rlim + i;
2214 rlim->rlim_cur = min(rlim->rlim_max, initrlim->rlim_cur);
2215 }
2216 task_unlock(current);
2217 update_rlimit_cpu(current, rlimit(RLIMIT_CPU));
2218 }
2219 }
2220
2221 /*
2222 * Clean up the process immediately after the installation of new credentials
2223 * due to exec
2224 */
2225 static void selinux_bprm_committed_creds(struct linux_binprm *bprm)
2226 {
2227 const struct task_security_struct *tsec = current_security();
2228 struct itimerval itimer;
2229 u32 osid, sid;
2230 int rc, i;
2231
2232 osid = tsec->osid;
2233 sid = tsec->sid;
2234
2235 if (sid == osid)
2236 return;
2237
2238 /* Check whether the new SID can inherit signal state from the old SID.
2239 * If not, clear itimers to avoid subsequent signal generation and
2240 * flush and unblock signals.
2241 *
2242 * This must occur _after_ the task SID has been updated so that any
2243 * kill done after the flush will be checked against the new SID.
2244 */
2245 rc = avc_has_perm(osid, sid, SECCLASS_PROCESS, PROCESS__SIGINH, NULL);
2246 if (rc) {
2247 memset(&itimer, 0, sizeof itimer);
2248 for (i = 0; i < 3; i++)
2249 do_setitimer(i, &itimer, NULL);
2250 spin_lock_irq(&current->sighand->siglock);
2251 if (!(current->signal->flags & SIGNAL_GROUP_EXIT)) {
2252 __flush_signals(current);
2253 flush_signal_handlers(current, 1);
2254 sigemptyset(&current->blocked);
2255 }
2256 spin_unlock_irq(&current->sighand->siglock);
2257 }
2258
2259 /* Wake up the parent if it is waiting so that it can recheck
2260 * wait permission to the new task SID. */
2261 read_lock(&tasklist_lock);
2262 __wake_up_parent(current, current->real_parent);
2263 read_unlock(&tasklist_lock);
2264 }
2265
2266 /* superblock security operations */
2267
2268 static int selinux_sb_alloc_security(struct super_block *sb)
2269 {
2270 return superblock_alloc_security(sb);
2271 }
2272
2273 static void selinux_sb_free_security(struct super_block *sb)
2274 {
2275 superblock_free_security(sb);
2276 }
2277
2278 static inline int match_prefix(char *prefix, int plen, char *option, int olen)
2279 {
2280 if (plen > olen)
2281 return 0;
2282
2283 return !memcmp(prefix, option, plen);
2284 }
2285
2286 static inline int selinux_option(char *option, int len)
2287 {
2288 return (match_prefix(CONTEXT_STR, sizeof(CONTEXT_STR)-1, option, len) ||
2289 match_prefix(FSCONTEXT_STR, sizeof(FSCONTEXT_STR)-1, option, len) ||
2290 match_prefix(DEFCONTEXT_STR, sizeof(DEFCONTEXT_STR)-1, option, len) ||
2291 match_prefix(ROOTCONTEXT_STR, sizeof(ROOTCONTEXT_STR)-1, option, len) ||
2292 match_prefix(LABELSUPP_STR, sizeof(LABELSUPP_STR)-1, option, len));
2293 }
2294
2295 static inline void take_option(char **to, char *from, int *first, int len)
2296 {
2297 if (!*first) {
2298 **to = ',';
2299 *to += 1;
2300 } else
2301 *first = 0;
2302 memcpy(*to, from, len);
2303 *to += len;
2304 }
2305
2306 static inline void take_selinux_option(char **to, char *from, int *first,
2307 int len)
2308 {
2309 int current_size = 0;
2310
2311 if (!*first) {
2312 **to = '|';
2313 *to += 1;
2314 } else
2315 *first = 0;
2316
2317 while (current_size < len) {
2318 if (*from != '"') {
2319 **to = *from;
2320 *to += 1;
2321 }
2322 from += 1;
2323 current_size += 1;
2324 }
2325 }
2326
2327 static int selinux_sb_copy_data(char *orig, char *copy)
2328 {
2329 int fnosec, fsec, rc = 0;
2330 char *in_save, *in_curr, *in_end;
2331 char *sec_curr, *nosec_save, *nosec;
2332 int open_quote = 0;
2333
2334 in_curr = orig;
2335 sec_curr = copy;
2336
2337 nosec = (char *)get_zeroed_page(GFP_KERNEL);
2338 if (!nosec) {
2339 rc = -ENOMEM;
2340 goto out;
2341 }
2342
2343 nosec_save = nosec;
2344 fnosec = fsec = 1;
2345 in_save = in_end = orig;
2346
2347 do {
2348 if (*in_end == '"')
2349 open_quote = !open_quote;
2350 if ((*in_end == ',' && open_quote == 0) ||
2351 *in_end == '\0') {
2352 int len = in_end - in_curr;
2353
2354 if (selinux_option(in_curr, len))
2355 take_selinux_option(&sec_curr, in_curr, &fsec, len);
2356 else
2357 take_option(&nosec, in_curr, &fnosec, len);
2358
2359 in_curr = in_end + 1;
2360 }
2361 } while (*in_end++);
2362
2363 strcpy(in_save, nosec_save);
2364 free_page((unsigned long)nosec_save);
2365 out:
2366 return rc;
2367 }
2368
2369 static int selinux_sb_remount(struct super_block *sb, void *data)
2370 {
2371 int rc, i, *flags;
2372 struct security_mnt_opts opts;
2373 char *secdata, **mount_options;
2374 struct superblock_security_struct *sbsec = sb->s_security;
2375
2376 if (!(sbsec->flags & SE_SBINITIALIZED))
2377 return 0;
2378
2379 if (!data)
2380 return 0;
2381
2382 if (sb->s_type->fs_flags & FS_BINARY_MOUNTDATA)
2383 return 0;
2384
2385 security_init_mnt_opts(&opts);
2386 secdata = alloc_secdata();
2387 if (!secdata)
2388 return -ENOMEM;
2389 rc = selinux_sb_copy_data(data, secdata);
2390 if (rc)
2391 goto out_free_secdata;
2392
2393 rc = selinux_parse_opts_str(secdata, &opts);
2394 if (rc)
2395 goto out_free_secdata;
2396
2397 mount_options = opts.mnt_opts;
2398 flags = opts.mnt_opts_flags;
2399
2400 for (i = 0; i < opts.num_mnt_opts; i++) {
2401 u32 sid;
2402 size_t len;
2403
2404 if (flags[i] == SE_SBLABELSUPP)
2405 continue;
2406 len = strlen(mount_options[i]);
2407 rc = security_context_to_sid(mount_options[i], len, &sid);
2408 if (rc) {
2409 printk(KERN_WARNING "SELinux: security_context_to_sid"
2410 "(%s) failed for (dev %s, type %s) errno=%d\n",
2411 mount_options[i], sb->s_id, sb->s_type->name, rc);
2412 goto out_free_opts;
2413 }
2414 rc = -EINVAL;
2415 switch (flags[i]) {
2416 case FSCONTEXT_MNT:
2417 if (bad_option(sbsec, FSCONTEXT_MNT, sbsec->sid, sid))
2418 goto out_bad_option;
2419 break;
2420 case CONTEXT_MNT:
2421 if (bad_option(sbsec, CONTEXT_MNT, sbsec->mntpoint_sid, sid))
2422 goto out_bad_option;
2423 break;
2424 case ROOTCONTEXT_MNT: {
2425 struct inode_security_struct *root_isec;
2426 root_isec = sb->s_root->d_inode->i_security;
2427
2428 if (bad_option(sbsec, ROOTCONTEXT_MNT, root_isec->sid, sid))
2429 goto out_bad_option;
2430 break;
2431 }
2432 case DEFCONTEXT_MNT:
2433 if (bad_option(sbsec, DEFCONTEXT_MNT, sbsec->def_sid, sid))
2434 goto out_bad_option;
2435 break;
2436 default:
2437 goto out_free_opts;
2438 }
2439 }
2440
2441 rc = 0;
2442 out_free_opts:
2443 security_free_mnt_opts(&opts);
2444 out_free_secdata:
2445 free_secdata(secdata);
2446 return rc;
2447 out_bad_option:
2448 printk(KERN_WARNING "SELinux: unable to change security options "
2449 "during remount (dev %s, type=%s)\n", sb->s_id,
2450 sb->s_type->name);
2451 goto out_free_opts;
2452 }
2453
2454 static int selinux_sb_kern_mount(struct super_block *sb, int flags, void *data)
2455 {
2456 const struct cred *cred = current_cred();
2457 struct common_audit_data ad;
2458 int rc;
2459
2460 rc = superblock_doinit(sb, data);
2461 if (rc)
2462 return rc;
2463
2464 /* Allow all mounts performed by the kernel */
2465 if (flags & MS_KERNMOUNT)
2466 return 0;
2467
2468 ad.type = LSM_AUDIT_DATA_DENTRY;
2469 ad.u.dentry = sb->s_root;
2470 return superblock_has_perm(cred, sb, FILESYSTEM__MOUNT, &ad);
2471 }
2472
2473 static int selinux_sb_statfs(struct dentry *dentry)
2474 {
2475 const struct cred *cred = current_cred();
2476 struct common_audit_data ad;
2477
2478 ad.type = LSM_AUDIT_DATA_DENTRY;
2479 ad.u.dentry = dentry->d_sb->s_root;
2480 return superblock_has_perm(cred, dentry->d_sb, FILESYSTEM__GETATTR, &ad);
2481 }
2482
2483 static int selinux_mount(const char *dev_name,
2484 struct path *path,
2485 const char *type,
2486 unsigned long flags,
2487 void *data)
2488 {
2489 const struct cred *cred = current_cred();
2490
2491 if (flags & MS_REMOUNT)
2492 return superblock_has_perm(cred, path->dentry->d_sb,
2493 FILESYSTEM__REMOUNT, NULL);
2494 else
2495 return path_has_perm(cred, path, FILE__MOUNTON);
2496 }
2497
2498 static int selinux_umount(struct vfsmount *mnt, int flags)
2499 {
2500 const struct cred *cred = current_cred();
2501
2502 return superblock_has_perm(cred, mnt->mnt_sb,
2503 FILESYSTEM__UNMOUNT, NULL);
2504 }
2505
2506 /* inode security operations */
2507
2508 static int selinux_inode_alloc_security(struct inode *inode)
2509 {
2510 return inode_alloc_security(inode);
2511 }
2512
2513 static void selinux_inode_free_security(struct inode *inode)
2514 {
2515 inode_free_security(inode);
2516 }
2517
2518 static int selinux_dentry_init_security(struct dentry *dentry, int mode,
2519 struct qstr *name, void **ctx,
2520 u32 *ctxlen)
2521 {
2522 const struct cred *cred = current_cred();
2523 struct task_security_struct *tsec;
2524 struct inode_security_struct *dsec;
2525 struct superblock_security_struct *sbsec;
2526 struct inode *dir = dentry->d_parent->d_inode;
2527 u32 newsid;
2528 int rc;
2529
2530 tsec = cred->security;
2531 dsec = dir->i_security;
2532 sbsec = dir->i_sb->s_security;
2533
2534 if (tsec->create_sid && sbsec->behavior != SECURITY_FS_USE_MNTPOINT) {
2535 newsid = tsec->create_sid;
2536 } else {
2537 rc = security_transition_sid(tsec->sid, dsec->sid,
2538 inode_mode_to_security_class(mode),
2539 name,
2540 &newsid);
2541 if (rc) {
2542 printk(KERN_WARNING
2543 "%s: security_transition_sid failed, rc=%d\n",
2544 __func__, -rc);
2545 return rc;
2546 }
2547 }
2548
2549 return security_sid_to_context(newsid, (char **)ctx, ctxlen);
2550 }
2551
2552 static int selinux_inode_init_security(struct inode *inode, struct inode *dir,
2553 const struct qstr *qstr, char **name,
2554 void **value, size_t *len)
2555 {
2556 const struct task_security_struct *tsec = current_security();
2557 struct inode_security_struct *dsec;
2558 struct superblock_security_struct *sbsec;
2559 u32 sid, newsid, clen;
2560 int rc;
2561 char *namep = NULL, *context;
2562
2563 dsec = dir->i_security;
2564 sbsec = dir->i_sb->s_security;
2565
2566 sid = tsec->sid;
2567 newsid = tsec->create_sid;
2568
2569 if ((sbsec->flags & SE_SBINITIALIZED) &&
2570 (sbsec->behavior == SECURITY_FS_USE_MNTPOINT))
2571 newsid = sbsec->mntpoint_sid;
2572 else if (!newsid || !(sbsec->flags & SE_SBLABELSUPP)) {
2573 rc = security_transition_sid(sid, dsec->sid,
2574 inode_mode_to_security_class(inode->i_mode),
2575 qstr, &newsid);
2576 if (rc) {
2577 printk(KERN_WARNING "%s: "
2578 "security_transition_sid failed, rc=%d (dev=%s "
2579 "ino=%ld)\n",
2580 __func__,
2581 -rc, inode->i_sb->s_id, inode->i_ino);
2582 return rc;
2583 }
2584 }
2585
2586 /* Possibly defer initialization to selinux_complete_init. */
2587 if (sbsec->flags & SE_SBINITIALIZED) {
2588 struct inode_security_struct *isec = inode->i_security;
2589 isec->sclass = inode_mode_to_security_class(inode->i_mode);
2590 isec->sid = newsid;
2591 isec->initialized = 1;
2592 }
2593
2594 if (!ss_initialized || !(sbsec->flags & SE_SBLABELSUPP))
2595 return -EOPNOTSUPP;
2596
2597 if (name) {
2598 namep = kstrdup(XATTR_SELINUX_SUFFIX, GFP_NOFS);
2599 if (!namep)
2600 return -ENOMEM;
2601 *name = namep;
2602 }
2603
2604 if (value && len) {
2605 rc = security_sid_to_context_force(newsid, &context, &clen);
2606 if (rc) {
2607 kfree(namep);
2608 return rc;
2609 }
2610 *value = context;
2611 *len = clen;
2612 }
2613
2614 return 0;
2615 }
2616
2617 static int selinux_inode_create(struct inode *dir, struct dentry *dentry, umode_t mode)
2618 {
2619 return may_create(dir, dentry, SECCLASS_FILE);
2620 }
2621
2622 static int selinux_inode_link(struct dentry *old_dentry, struct inode *dir, struct dentry *new_dentry)
2623 {
2624 return may_link(dir, old_dentry, MAY_LINK);
2625 }
2626
2627 static int selinux_inode_unlink(struct inode *dir, struct dentry *dentry)
2628 {
2629 return may_link(dir, dentry, MAY_UNLINK);
2630 }
2631
2632 static int selinux_inode_symlink(struct inode *dir, struct dentry *dentry, const char *name)
2633 {
2634 return may_create(dir, dentry, SECCLASS_LNK_FILE);
2635 }
2636
2637 static int selinux_inode_mkdir(struct inode *dir, struct dentry *dentry, umode_t mask)
2638 {
2639 return may_create(dir, dentry, SECCLASS_DIR);
2640 }
2641
2642 static int selinux_inode_rmdir(struct inode *dir, struct dentry *dentry)
2643 {
2644 return may_link(dir, dentry, MAY_RMDIR);
2645 }
2646
2647 static int selinux_inode_mknod(struct inode *dir, struct dentry *dentry, umode_t mode, dev_t dev)
2648 {
2649 return may_create(dir, dentry, inode_mode_to_security_class(mode));
2650 }
2651
2652 static int selinux_inode_rename(struct inode *old_inode, struct dentry *old_dentry,
2653 struct inode *new_inode, struct dentry *new_dentry)
2654 {
2655 return may_rename(old_inode, old_dentry, new_inode, new_dentry);
2656 }
2657
2658 static int selinux_inode_readlink(struct dentry *dentry)
2659 {
2660 const struct cred *cred = current_cred();
2661
2662 return dentry_has_perm(cred, dentry, FILE__READ);
2663 }
2664
2665 static int selinux_inode_follow_link(struct dentry *dentry, struct nameidata *nameidata)
2666 {
2667 const struct cred *cred = current_cred();
2668
2669 return dentry_has_perm(cred, dentry, FILE__READ);
2670 }
2671
2672 static noinline int audit_inode_permission(struct inode *inode,
2673 u32 perms, u32 audited, u32 denied,
2674 unsigned flags)
2675 {
2676 struct common_audit_data ad;
2677 struct inode_security_struct *isec = inode->i_security;
2678 int rc;
2679
2680 ad.type = LSM_AUDIT_DATA_INODE;
2681 ad.u.inode = inode;
2682
2683 rc = slow_avc_audit(current_sid(), isec->sid, isec->sclass, perms,
2684 audited, denied, &ad, flags);
2685 if (rc)
2686 return rc;
2687 return 0;
2688 }
2689
2690 static int selinux_inode_permission(struct inode *inode, int mask)
2691 {
2692 const struct cred *cred = current_cred();
2693 u32 perms;
2694 bool from_access;
2695 unsigned flags = mask & MAY_NOT_BLOCK;
2696 struct inode_security_struct *isec;
2697 u32 sid;
2698 struct av_decision avd;
2699 int rc, rc2;
2700 u32 audited, denied;
2701
2702 from_access = mask & MAY_ACCESS;
2703 mask &= (MAY_READ|MAY_WRITE|MAY_EXEC|MAY_APPEND);
2704
2705 /* No permission to check. Existence test. */
2706 if (!mask)
2707 return 0;
2708
2709 validate_creds(cred);
2710
2711 if (unlikely(IS_PRIVATE(inode)))
2712 return 0;
2713
2714 perms = file_mask_to_av(inode->i_mode, mask);
2715
2716 sid = cred_sid(cred);
2717 isec = inode->i_security;
2718
2719 rc = avc_has_perm_noaudit(sid, isec->sid, isec->sclass, perms, 0, &avd);
2720 audited = avc_audit_required(perms, &avd, rc,
2721 from_access ? FILE__AUDIT_ACCESS : 0,
2722 &denied);
2723 if (likely(!audited))
2724 return rc;
2725
2726 rc2 = audit_inode_permission(inode, perms, audited, denied, flags);
2727 if (rc2)
2728 return rc2;
2729 return rc;
2730 }
2731
2732 static int selinux_inode_setattr(struct dentry *dentry, struct iattr *iattr)
2733 {
2734 const struct cred *cred = current_cred();
2735 unsigned int ia_valid = iattr->ia_valid;
2736 __u32 av = FILE__WRITE;
2737
2738 /* ATTR_FORCE is just used for ATTR_KILL_S[UG]ID. */
2739 if (ia_valid & ATTR_FORCE) {
2740 ia_valid &= ~(ATTR_KILL_SUID | ATTR_KILL_SGID | ATTR_MODE |
2741 ATTR_FORCE);
2742 if (!ia_valid)
2743 return 0;
2744 }
2745
2746 if (ia_valid & (ATTR_MODE | ATTR_UID | ATTR_GID |
2747 ATTR_ATIME_SET | ATTR_MTIME_SET | ATTR_TIMES_SET))
2748 return dentry_has_perm(cred, dentry, FILE__SETATTR);
2749
2750 if (selinux_policycap_openperm && (ia_valid & ATTR_SIZE))
2751 av |= FILE__OPEN;
2752
2753 return dentry_has_perm(cred, dentry, av);
2754 }
2755
2756 static int selinux_inode_getattr(struct vfsmount *mnt, struct dentry *dentry)
2757 {
2758 const struct cred *cred = current_cred();
2759 struct path path;
2760
2761 path.dentry = dentry;
2762 path.mnt = mnt;
2763
2764 return path_has_perm(cred, &path, FILE__GETATTR);
2765 }
2766
2767 static int selinux_inode_setotherxattr(struct dentry *dentry, const char *name)
2768 {
2769 const struct cred *cred = current_cred();
2770
2771 if (!strncmp(name, XATTR_SECURITY_PREFIX,
2772 sizeof XATTR_SECURITY_PREFIX - 1)) {
2773 if (!strcmp(name, XATTR_NAME_CAPS)) {
2774 if (!capable(CAP_SETFCAP))
2775 return -EPERM;
2776 } else if (!capable(CAP_SYS_ADMIN)) {
2777 /* A different attribute in the security namespace.
2778 Restrict to administrator. */
2779 return -EPERM;
2780 }
2781 }
2782
2783 /* Not an attribute we recognize, so just check the
2784 ordinary setattr permission. */
2785 return dentry_has_perm(cred, dentry, FILE__SETATTR);
2786 }
2787
2788 static int selinux_inode_setxattr(struct dentry *dentry, const char *name,
2789 const void *value, size_t size, int flags)
2790 {
2791 struct inode *inode = dentry->d_inode;
2792 struct inode_security_struct *isec = inode->i_security;
2793 struct superblock_security_struct *sbsec;
2794 struct common_audit_data ad;
2795 u32 newsid, sid = current_sid();
2796 int rc = 0;
2797
2798 if (strcmp(name, XATTR_NAME_SELINUX))
2799 return selinux_inode_setotherxattr(dentry, name);
2800
2801 sbsec = inode->i_sb->s_security;
2802 if (!(sbsec->flags & SE_SBLABELSUPP))
2803 return -EOPNOTSUPP;
2804
2805 if (!inode_owner_or_capable(inode))
2806 return -EPERM;
2807
2808 ad.type = LSM_AUDIT_DATA_DENTRY;
2809 ad.u.dentry = dentry;
2810
2811 rc = avc_has_perm(sid, isec->sid, isec->sclass,
2812 FILE__RELABELFROM, &ad);
2813 if (rc)
2814 return rc;
2815
2816 rc = security_context_to_sid(value, size, &newsid);
2817 if (rc == -EINVAL) {
2818 if (!capable(CAP_MAC_ADMIN)) {
2819 struct audit_buffer *ab;
2820 size_t audit_size;
2821 const char *str;
2822
2823 /* We strip a nul only if it is at the end, otherwise the
2824 * context contains a nul and we should audit that */
2825 if (value) {
2826 str = value;
2827 if (str[size - 1] == '\0')
2828 audit_size = size - 1;
2829 else
2830 audit_size = size;
2831 } else {
2832 str = "";
2833 audit_size = 0;
2834 }
2835 ab = audit_log_start(current->audit_context, GFP_ATOMIC, AUDIT_SELINUX_ERR);
2836 audit_log_format(ab, "op=setxattr invalid_context=");
2837 audit_log_n_untrustedstring(ab, value, audit_size);
2838 audit_log_end(ab);
2839
2840 return rc;
2841 }
2842 rc = security_context_to_sid_force(value, size, &newsid);
2843 }
2844 if (rc)
2845 return rc;
2846
2847 rc = avc_has_perm(sid, newsid, isec->sclass,
2848 FILE__RELABELTO, &ad);
2849 if (rc)
2850 return rc;
2851
2852 rc = security_validate_transition(isec->sid, newsid, sid,
2853 isec->sclass);
2854 if (rc)
2855 return rc;
2856
2857 return avc_has_perm(newsid,
2858 sbsec->sid,
2859 SECCLASS_FILESYSTEM,
2860 FILESYSTEM__ASSOCIATE,
2861 &ad);
2862 }
2863
2864 static void selinux_inode_post_setxattr(struct dentry *dentry, const char *name,
2865 const void *value, size_t size,
2866 int flags)
2867 {
2868 struct inode *inode = dentry->d_inode;
2869 struct inode_security_struct *isec = inode->i_security;
2870 u32 newsid;
2871 int rc;
2872
2873 if (strcmp(name, XATTR_NAME_SELINUX)) {
2874 /* Not an attribute we recognize, so nothing to do. */
2875 return;
2876 }
2877
2878 rc = security_context_to_sid_force(value, size, &newsid);
2879 if (rc) {
2880 printk(KERN_ERR "SELinux: unable to map context to SID"
2881 "for (%s, %lu), rc=%d\n",
2882 inode->i_sb->s_id, inode->i_ino, -rc);
2883 return;
2884 }
2885
2886 isec->sid = newsid;
2887 return;
2888 }
2889
2890 static int selinux_inode_getxattr(struct dentry *dentry, const char *name)
2891 {
2892 const struct cred *cred = current_cred();
2893
2894 return dentry_has_perm(cred, dentry, FILE__GETATTR);
2895 }
2896
2897 static int selinux_inode_listxattr(struct dentry *dentry)
2898 {
2899 const struct cred *cred = current_cred();
2900
2901 return dentry_has_perm(cred, dentry, FILE__GETATTR);
2902 }
2903
2904 static int selinux_inode_removexattr(struct dentry *dentry, const char *name)
2905 {
2906 if (strcmp(name, XATTR_NAME_SELINUX))
2907 return selinux_inode_setotherxattr(dentry, name);
2908
2909 /* No one is allowed to remove a SELinux security label.
2910 You can change the label, but all data must be labeled. */
2911 return -EACCES;
2912 }
2913
2914 /*
2915 * Copy the inode security context value to the user.
2916 *
2917 * Permission check is handled by selinux_inode_getxattr hook.
2918 */
2919 static int selinux_inode_getsecurity(const struct inode *inode, const char *name, void **buffer, bool alloc)
2920 {
2921 u32 size;
2922 int error;
2923 char *context = NULL;
2924 struct inode_security_struct *isec = inode->i_security;
2925
2926 if (strcmp(name, XATTR_SELINUX_SUFFIX))
2927 return -EOPNOTSUPP;
2928
2929 /*
2930 * If the caller has CAP_MAC_ADMIN, then get the raw context
2931 * value even if it is not defined by current policy; otherwise,
2932 * use the in-core value under current policy.
2933 * Use the non-auditing forms of the permission checks since
2934 * getxattr may be called by unprivileged processes commonly
2935 * and lack of permission just means that we fall back to the
2936 * in-core context value, not a denial.
2937 */
2938 error = selinux_capable(current_cred(), &init_user_ns, CAP_MAC_ADMIN,
2939 SECURITY_CAP_NOAUDIT);
2940 if (!error)
2941 error = security_sid_to_context_force(isec->sid, &context,
2942 &size);
2943 else
2944 error = security_sid_to_context(isec->sid, &context, &size);
2945 if (error)
2946 return error;
2947 error = size;
2948 if (alloc) {
2949 *buffer = context;
2950 goto out_nofree;
2951 }
2952 kfree(context);
2953 out_nofree:
2954 return error;
2955 }
2956
2957 static int selinux_inode_setsecurity(struct inode *inode, const char *name,
2958 const void *value, size_t size, int flags)
2959 {
2960 struct inode_security_struct *isec = inode->i_security;
2961 u32 newsid;
2962 int rc;
2963
2964 if (strcmp(name, XATTR_SELINUX_SUFFIX))
2965 return -EOPNOTSUPP;
2966
2967 if (!value || !size)
2968 return -EACCES;
2969
2970 rc = security_context_to_sid((void *)value, size, &newsid);
2971 if (rc)
2972 return rc;
2973
2974 isec->sid = newsid;
2975 isec->initialized = 1;
2976 return 0;
2977 }
2978
2979 static int selinux_inode_listsecurity(struct inode *inode, char *buffer, size_t buffer_size)
2980 {
2981 const int len = sizeof(XATTR_NAME_SELINUX);
2982 if (buffer && len <= buffer_size)
2983 memcpy(buffer, XATTR_NAME_SELINUX, len);
2984 return len;
2985 }
2986
2987 static void selinux_inode_getsecid(const struct inode *inode, u32 *secid)
2988 {
2989 struct inode_security_struct *isec = inode->i_security;
2990 *secid = isec->sid;
2991 }
2992
2993 /* file security operations */
2994
2995 static int selinux_revalidate_file_permission(struct file *file, int mask)
2996 {
2997 const struct cred *cred = current_cred();
2998 struct inode *inode = file_inode(file);
2999
3000 /* file_mask_to_av won't add FILE__WRITE if MAY_APPEND is set */
3001 if ((file->f_flags & O_APPEND) && (mask & MAY_WRITE))
3002 mask |= MAY_APPEND;
3003
3004 return file_has_perm(cred, file,
3005 file_mask_to_av(inode->i_mode, mask));
3006 }
3007
3008 static int selinux_file_permission(struct file *file, int mask)
3009 {
3010 struct inode *inode = file_inode(file);
3011 struct file_security_struct *fsec = file->f_security;
3012 struct inode_security_struct *isec = inode->i_security;
3013 u32 sid = current_sid();
3014
3015 if (!mask)
3016 /* No permission to check. Existence test. */
3017 return 0;
3018
3019 if (sid == fsec->sid && fsec->isid == isec->sid &&
3020 fsec->pseqno == avc_policy_seqno())
3021 /* No change since file_open check. */
3022 return 0;
3023
3024 return selinux_revalidate_file_permission(file, mask);
3025 }
3026
3027 static int selinux_file_alloc_security(struct file *file)
3028 {
3029 return file_alloc_security(file);
3030 }
3031
3032 static void selinux_file_free_security(struct file *file)
3033 {
3034 file_free_security(file);
3035 }
3036
3037 static int selinux_file_ioctl(struct file *file, unsigned int cmd,
3038 unsigned long arg)
3039 {
3040 const struct cred *cred = current_cred();
3041 int error = 0;
3042
3043 switch (cmd) {
3044 case FIONREAD:
3045 /* fall through */
3046 case FIBMAP:
3047 /* fall through */
3048 case FIGETBSZ:
3049 /* fall through */
3050 case FS_IOC_GETFLAGS:
3051 /* fall through */
3052 case FS_IOC_GETVERSION:
3053 error = file_has_perm(cred, file, FILE__GETATTR);
3054 break;
3055
3056 case FS_IOC_SETFLAGS:
3057 /* fall through */
3058 case FS_IOC_SETVERSION:
3059 error = file_has_perm(cred, file, FILE__SETATTR);
3060 break;
3061
3062 /* sys_ioctl() checks */
3063 case FIONBIO:
3064 /* fall through */
3065 case FIOASYNC:
3066 error = file_has_perm(cred, file, 0);
3067 break;
3068
3069 case KDSKBENT:
3070 case KDSKBSENT:
3071 error = cred_has_capability(cred, CAP_SYS_TTY_CONFIG,
3072 SECURITY_CAP_AUDIT);
3073 break;
3074
3075 /* default case assumes that the command will go
3076 * to the file's ioctl() function.
3077 */
3078 default:
3079 error = file_has_perm(cred, file, FILE__IOCTL);
3080 }
3081 return error;
3082 }
3083
3084 static int default_noexec;
3085
3086 static int file_map_prot_check(struct file *file, unsigned long prot, int shared)
3087 {
3088 const struct cred *cred = current_cred();
3089 int rc = 0;
3090
3091 if (default_noexec &&
3092 (prot & PROT_EXEC) && (!file || (!shared && (prot & PROT_WRITE)))) {
3093 /*
3094 * We are making executable an anonymous mapping or a
3095 * private file mapping that will also be writable.
3096 * This has an additional check.
3097 */
3098 rc = cred_has_perm(cred, cred, PROCESS__EXECMEM);
3099 if (rc)
3100 goto error;
3101 }
3102
3103 if (file) {
3104 /* read access is always possible with a mapping */
3105 u32 av = FILE__READ;
3106
3107 /* write access only matters if the mapping is shared */
3108 if (shared && (prot & PROT_WRITE))
3109 av |= FILE__WRITE;
3110
3111 if (prot & PROT_EXEC)
3112 av |= FILE__EXECUTE;
3113
3114 return file_has_perm(cred, file, av);
3115 }
3116
3117 error:
3118 return rc;
3119 }
3120
3121 static int selinux_mmap_addr(unsigned long addr)
3122 {
3123 int rc = 0;
3124 u32 sid = current_sid();
3125
3126 /*
3127 * notice that we are intentionally putting the SELinux check before
3128 * the secondary cap_file_mmap check. This is such a likely attempt
3129 * at bad behaviour/exploit that we always want to get the AVC, even
3130 * if DAC would have also denied the operation.
3131 */
3132 if (addr < CONFIG_LSM_MMAP_MIN_ADDR) {
3133 rc = avc_has_perm(sid, sid, SECCLASS_MEMPROTECT,
3134 MEMPROTECT__MMAP_ZERO, NULL);
3135 if (rc)
3136 return rc;
3137 }
3138
3139 /* do DAC check on address space usage */
3140 return cap_mmap_addr(addr);
3141 }
3142
3143 static int selinux_mmap_file(struct file *file, unsigned long reqprot,
3144 unsigned long prot, unsigned long flags)
3145 {
3146 if (selinux_checkreqprot)
3147 prot = reqprot;
3148
3149 return file_map_prot_check(file, prot,
3150 (flags & MAP_TYPE) == MAP_SHARED);
3151 }
3152
3153 static int selinux_file_mprotect(struct vm_area_struct *vma,
3154 unsigned long reqprot,
3155 unsigned long prot)
3156 {
3157 const struct cred *cred = current_cred();
3158
3159 if (selinux_checkreqprot)
3160 prot = reqprot;
3161
3162 if (default_noexec &&
3163 (prot & PROT_EXEC) && !(vma->vm_flags & VM_EXEC)) {
3164 int rc = 0;
3165 if (vma->vm_start >= vma->vm_mm->start_brk &&
3166 vma->vm_end <= vma->vm_mm->brk) {
3167 rc = cred_has_perm(cred, cred, PROCESS__EXECHEAP);
3168 } else if (!vma->vm_file &&
3169 vma->vm_start <= vma->vm_mm->start_stack &&
3170 vma->vm_end >= vma->vm_mm->start_stack) {
3171 rc = current_has_perm(current, PROCESS__EXECSTACK);
3172 } else if (vma->vm_file && vma->anon_vma) {
3173 /*
3174 * We are making executable a file mapping that has
3175 * had some COW done. Since pages might have been
3176 * written, check ability to execute the possibly
3177 * modified content. This typically should only
3178 * occur for text relocations.
3179 */
3180 rc = file_has_perm(cred, vma->vm_file, FILE__EXECMOD);
3181 }
3182 if (rc)
3183 return rc;
3184 }
3185
3186 return file_map_prot_check(vma->vm_file, prot, vma->vm_flags&VM_SHARED);
3187 }
3188
3189 static int selinux_file_lock(struct file *file, unsigned int cmd)
3190 {
3191 const struct cred *cred = current_cred();
3192
3193 return file_has_perm(cred, file, FILE__LOCK);
3194 }
3195
3196 static int selinux_file_fcntl(struct file *file, unsigned int cmd,
3197 unsigned long arg)
3198 {
3199 const struct cred *cred = current_cred();
3200 int err = 0;
3201
3202 switch (cmd) {
3203 case F_SETFL:
3204 if ((file->f_flags & O_APPEND) && !(arg & O_APPEND)) {
3205 err = file_has_perm(cred, file, FILE__WRITE);
3206 break;
3207 }
3208 /* fall through */
3209 case F_SETOWN:
3210 case F_SETSIG:
3211 case F_GETFL:
3212 case F_GETOWN:
3213 case F_GETSIG:
3214 case F_GETOWNER_UIDS:
3215 /* Just check FD__USE permission */
3216 err = file_has_perm(cred, file, 0);
3217 break;
3218 case F_GETLK:
3219 case F_SETLK:
3220 case F_SETLKW:
3221 #if BITS_PER_LONG == 32
3222 case F_GETLK64:
3223 case F_SETLK64:
3224 case F_SETLKW64:
3225 #endif
3226 err = file_has_perm(cred, file, FILE__LOCK);
3227 break;
3228 }
3229
3230 return err;
3231 }
3232
3233 static int selinux_file_set_fowner(struct file *file)
3234 {
3235 struct file_security_struct *fsec;
3236
3237 fsec = file->f_security;
3238 fsec->fown_sid = current_sid();
3239
3240 return 0;
3241 }
3242
3243 static int selinux_file_send_sigiotask(struct task_struct *tsk,
3244 struct fown_struct *fown, int signum)
3245 {
3246 struct file *file;
3247 u32 sid = task_sid(tsk);
3248 u32 perm;
3249 struct file_security_struct *fsec;
3250
3251 /* struct fown_struct is never outside the context of a struct file */
3252 file = container_of(fown, struct file, f_owner);
3253
3254 fsec = file->f_security;
3255
3256 if (!signum)
3257 perm = signal_to_av(SIGIO); /* as per send_sigio_to_task */
3258 else
3259 perm = signal_to_av(signum);
3260
3261 return avc_has_perm(fsec->fown_sid, sid,
3262 SECCLASS_PROCESS, perm, NULL);
3263 }
3264
3265 static int selinux_file_receive(struct file *file)
3266 {
3267 const struct cred *cred = current_cred();
3268
3269 return file_has_perm(cred, file, file_to_av(file));
3270 }
3271
3272 static int selinux_file_open(struct file *file, const struct cred *cred)
3273 {
3274 struct file_security_struct *fsec;
3275 struct inode_security_struct *isec;
3276
3277 fsec = file->f_security;
3278 isec = file_inode(file)->i_security;
3279 /*
3280 * Save inode label and policy sequence number
3281 * at open-time so that selinux_file_permission
3282 * can determine whether revalidation is necessary.
3283 * Task label is already saved in the file security
3284 * struct as its SID.
3285 */
3286 fsec->isid = isec->sid;
3287 fsec->pseqno = avc_policy_seqno();
3288 /*
3289 * Since the inode label or policy seqno may have changed
3290 * between the selinux_inode_permission check and the saving
3291 * of state above, recheck that access is still permitted.
3292 * Otherwise, access might never be revalidated against the
3293 * new inode label or new policy.
3294 * This check is not redundant - do not remove.
3295 */
3296 return path_has_perm(cred, &file->f_path, open_file_to_av(file));
3297 }
3298
3299 /* task security operations */
3300
3301 static int selinux_task_create(unsigned long clone_flags)
3302 {
3303 return current_has_perm(current, PROCESS__FORK);
3304 }
3305
3306 /*
3307 * allocate the SELinux part of blank credentials
3308 */
3309 static int selinux_cred_alloc_blank(struct cred *cred, gfp_t gfp)
3310 {
3311 struct task_security_struct *tsec;
3312
3313 tsec = kzalloc(sizeof(struct task_security_struct), gfp);
3314 if (!tsec)
3315 return -ENOMEM;
3316
3317 cred->security = tsec;
3318 return 0;
3319 }
3320
3321 /*
3322 * detach and free the LSM part of a set of credentials
3323 */
3324 static void selinux_cred_free(struct cred *cred)
3325 {
3326 struct task_security_struct *tsec = cred->security;
3327
3328 /*
3329 * cred->security == NULL if security_cred_alloc_blank() or
3330 * security_prepare_creds() returned an error.
3331 */
3332 BUG_ON(cred->security && (unsigned long) cred->security < PAGE_SIZE);
3333 cred->security = (void *) 0x7UL;
3334 kfree(tsec);
3335 }
3336
3337 /*
3338 * prepare a new set of credentials for modification
3339 */
3340 static int selinux_cred_prepare(struct cred *new, const struct cred *old,
3341 gfp_t gfp)
3342 {
3343 const struct task_security_struct *old_tsec;
3344 struct task_security_struct *tsec;
3345
3346 old_tsec = old->security;
3347
3348 tsec = kmemdup(old_tsec, sizeof(struct task_security_struct), gfp);
3349 if (!tsec)
3350 return -ENOMEM;
3351
3352 new->security = tsec;
3353 return 0;
3354 }
3355
3356 /*
3357 * transfer the SELinux data to a blank set of creds
3358 */
3359 static void selinux_cred_transfer(struct cred *new, const struct cred *old)
3360 {
3361 const struct task_security_struct *old_tsec = old->security;
3362 struct task_security_struct *tsec = new->security;
3363
3364 *tsec = *old_tsec;
3365 }
3366
3367 /*
3368 * set the security data for a kernel service
3369 * - all the creation contexts are set to unlabelled
3370 */
3371 static int selinux_kernel_act_as(struct cred *new, u32 secid)
3372 {
3373 struct task_security_struct *tsec = new->security;
3374 u32 sid = current_sid();
3375 int ret;
3376
3377 ret = avc_has_perm(sid, secid,
3378 SECCLASS_KERNEL_SERVICE,
3379 KERNEL_SERVICE__USE_AS_OVERRIDE,
3380 NULL);
3381 if (ret == 0) {
3382 tsec->sid = secid;
3383 tsec->create_sid = 0;
3384 tsec->keycreate_sid = 0;
3385 tsec->sockcreate_sid = 0;
3386 }
3387 return ret;
3388 }
3389
3390 /*
3391 * set the file creation context in a security record to the same as the
3392 * objective context of the specified inode
3393 */
3394 static int selinux_kernel_create_files_as(struct cred *new, struct inode *inode)
3395 {
3396 struct inode_security_struct *isec = inode->i_security;
3397 struct task_security_struct *tsec = new->security;
3398 u32 sid = current_sid();
3399 int ret;
3400
3401 ret = avc_has_perm(sid, isec->sid,
3402 SECCLASS_KERNEL_SERVICE,
3403 KERNEL_SERVICE__CREATE_FILES_AS,
3404 NULL);
3405
3406 if (ret == 0)
3407 tsec->create_sid = isec->sid;
3408 return ret;
3409 }
3410
3411 static int selinux_kernel_module_request(char *kmod_name)
3412 {
3413 u32 sid;
3414 struct common_audit_data ad;
3415
3416 sid = task_sid(current);
3417
3418 ad.type = LSM_AUDIT_DATA_KMOD;
3419 ad.u.kmod_name = kmod_name;
3420
3421 return avc_has_perm(sid, SECINITSID_KERNEL, SECCLASS_SYSTEM,
3422 SYSTEM__MODULE_REQUEST, &ad);
3423 }
3424
3425 static int selinux_task_setpgid(struct task_struct *p, pid_t pgid)
3426 {
3427 return current_has_perm(p, PROCESS__SETPGID);
3428 }
3429
3430 static int selinux_task_getpgid(struct task_struct *p)
3431 {
3432 return current_has_perm(p, PROCESS__GETPGID);
3433 }
3434
3435 static int selinux_task_getsid(struct task_struct *p)
3436 {
3437 return current_has_perm(p, PROCESS__GETSESSION);
3438 }
3439
3440 static void selinux_task_getsecid(struct task_struct *p, u32 *secid)
3441 {
3442 *secid = task_sid(p);
3443 }
3444
3445 static int selinux_task_setnice(struct task_struct *p, int nice)
3446 {
3447 int rc;
3448
3449 rc = cap_task_setnice(p, nice);
3450 if (rc)
3451 return rc;
3452
3453 return current_has_perm(p, PROCESS__SETSCHED);
3454 }
3455
3456 static int selinux_task_setioprio(struct task_struct *p, int ioprio)
3457 {
3458 int rc;
3459
3460 rc = cap_task_setioprio(p, ioprio);
3461 if (rc)
3462 return rc;
3463
3464 return current_has_perm(p, PROCESS__SETSCHED);
3465 }
3466
3467 static int selinux_task_getioprio(struct task_struct *p)
3468 {
3469 return current_has_perm(p, PROCESS__GETSCHED);
3470 }
3471
3472 static int selinux_task_setrlimit(struct task_struct *p, unsigned int resource,
3473 struct rlimit *new_rlim)
3474 {
3475 struct rlimit *old_rlim = p->signal->rlim + resource;
3476
3477 /* Control the ability to change the hard limit (whether
3478 lowering or raising it), so that the hard limit can
3479 later be used as a safe reset point for the soft limit
3480 upon context transitions. See selinux_bprm_committing_creds. */
3481 if (old_rlim->rlim_max != new_rlim->rlim_max)
3482 return current_has_perm(p, PROCESS__SETRLIMIT);
3483
3484 return 0;
3485 }
3486
3487 static int selinux_task_setscheduler(struct task_struct *p)
3488 {
3489 int rc;
3490
3491 rc = cap_task_setscheduler(p);
3492 if (rc)
3493 return rc;
3494
3495 return current_has_perm(p, PROCESS__SETSCHED);
3496 }
3497
3498 static int selinux_task_getscheduler(struct task_struct *p)
3499 {
3500 return current_has_perm(p, PROCESS__GETSCHED);
3501 }
3502
3503 static int selinux_task_movememory(struct task_struct *p)
3504 {
3505 return current_has_perm(p, PROCESS__SETSCHED);
3506 }
3507
3508 static int selinux_task_kill(struct task_struct *p, struct siginfo *info,
3509 int sig, u32 secid)
3510 {
3511 u32 perm;
3512 int rc;
3513
3514 if (!sig)
3515 perm = PROCESS__SIGNULL; /* null signal; existence test */
3516 else
3517 perm = signal_to_av(sig);
3518 if (secid)
3519 rc = avc_has_perm(secid, task_sid(p),
3520 SECCLASS_PROCESS, perm, NULL);
3521 else
3522 rc = current_has_perm(p, perm);
3523 return rc;
3524 }
3525
3526 static int selinux_task_wait(struct task_struct *p)
3527 {
3528 return task_has_perm(p, current, PROCESS__SIGCHLD);
3529 }
3530
3531 static void selinux_task_to_inode(struct task_struct *p,
3532 struct inode *inode)
3533 {
3534 struct inode_security_struct *isec = inode->i_security;
3535 u32 sid = task_sid(p);
3536
3537 isec->sid = sid;
3538 isec->initialized = 1;
3539 }
3540
3541 /* Returns error only if unable to parse addresses */
3542 static int selinux_parse_skb_ipv4(struct sk_buff *skb,
3543 struct common_audit_data *ad, u8 *proto)
3544 {
3545 int offset, ihlen, ret = -EINVAL;
3546 struct iphdr _iph, *ih;
3547
3548 offset = skb_network_offset(skb);
3549 ih = skb_header_pointer(skb, offset, sizeof(_iph), &_iph);
3550 if (ih == NULL)
3551 goto out;
3552
3553 ihlen = ih->ihl * 4;
3554 if (ihlen < sizeof(_iph))
3555 goto out;
3556
3557 ad->u.net->v4info.saddr = ih->saddr;
3558 ad->u.net->v4info.daddr = ih->daddr;
3559 ret = 0;
3560
3561 if (proto)
3562 *proto = ih->protocol;
3563
3564 switch (ih->protocol) {
3565 case IPPROTO_TCP: {
3566 struct tcphdr _tcph, *th;
3567
3568 if (ntohs(ih->frag_off) & IP_OFFSET)
3569 break;
3570
3571 offset += ihlen;
3572 th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph);
3573 if (th == NULL)
3574 break;
3575
3576 ad->u.net->sport = th->source;
3577 ad->u.net->dport = th->dest;
3578 break;
3579 }
3580
3581 case IPPROTO_UDP: {
3582 struct udphdr _udph, *uh;
3583
3584 if (ntohs(ih->frag_off) & IP_OFFSET)
3585 break;
3586
3587 offset += ihlen;
3588 uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph);
3589 if (uh == NULL)
3590 break;
3591
3592 ad->u.net->sport = uh->source;
3593 ad->u.net->dport = uh->dest;
3594 break;
3595 }
3596
3597 case IPPROTO_DCCP: {
3598 struct dccp_hdr _dccph, *dh;
3599
3600 if (ntohs(ih->frag_off) & IP_OFFSET)
3601 break;
3602
3603 offset += ihlen;
3604 dh = skb_header_pointer(skb, offset, sizeof(_dccph), &_dccph);
3605 if (dh == NULL)
3606 break;
3607
3608 ad->u.net->sport = dh->dccph_sport;
3609 ad->u.net->dport = dh->dccph_dport;
3610 break;
3611 }
3612
3613 default:
3614 break;
3615 }
3616 out:
3617 return ret;
3618 }
3619
3620 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
3621
3622 /* Returns error only if unable to parse addresses */
3623 static int selinux_parse_skb_ipv6(struct sk_buff *skb,
3624 struct common_audit_data *ad, u8 *proto)
3625 {
3626 u8 nexthdr;
3627 int ret = -EINVAL, offset;
3628 struct ipv6hdr _ipv6h, *ip6;
3629 __be16 frag_off;
3630
3631 offset = skb_network_offset(skb);
3632 ip6 = skb_header_pointer(skb, offset, sizeof(_ipv6h), &_ipv6h);
3633 if (ip6 == NULL)
3634 goto out;
3635
3636 ad->u.net->v6info.saddr = ip6->saddr;
3637 ad->u.net->v6info.daddr = ip6->daddr;
3638 ret = 0;
3639
3640 nexthdr = ip6->nexthdr;
3641 offset += sizeof(_ipv6h);
3642 offset = ipv6_skip_exthdr(skb, offset, &nexthdr, &frag_off);
3643 if (offset < 0)
3644 goto out;
3645
3646 if (proto)
3647 *proto = nexthdr;
3648
3649 switch (nexthdr) {
3650 case IPPROTO_TCP: {
3651 struct tcphdr _tcph, *th;
3652
3653 th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph);
3654 if (th == NULL)
3655 break;
3656
3657 ad->u.net->sport = th->source;
3658 ad->u.net->dport = th->dest;
3659 break;
3660 }
3661
3662 case IPPROTO_UDP: {
3663 struct udphdr _udph, *uh;
3664
3665 uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph);
3666 if (uh == NULL)
3667 break;
3668
3669 ad->u.net->sport = uh->source;
3670 ad->u.net->dport = uh->dest;
3671 break;
3672 }
3673
3674 case IPPROTO_DCCP: {
3675 struct dccp_hdr _dccph, *dh;
3676
3677 dh = skb_header_pointer(skb, offset, sizeof(_dccph), &_dccph);
3678 if (dh == NULL)
3679 break;
3680
3681 ad->u.net->sport = dh->dccph_sport;
3682 ad->u.net->dport = dh->dccph_dport;
3683 break;
3684 }
3685
3686 /* includes fragments */
3687 default:
3688 break;
3689 }
3690 out:
3691 return ret;
3692 }
3693
3694 #endif /* IPV6 */
3695
3696 static int selinux_parse_skb(struct sk_buff *skb, struct common_audit_data *ad,
3697 char **_addrp, int src, u8 *proto)
3698 {
3699 char *addrp;
3700 int ret;
3701
3702 switch (ad->u.net->family) {
3703 case PF_INET:
3704 ret = selinux_parse_skb_ipv4(skb, ad, proto);
3705 if (ret)
3706 goto parse_error;
3707 addrp = (char *)(src ? &ad->u.net->v4info.saddr :
3708 &ad->u.net->v4info.daddr);
3709 goto okay;
3710
3711 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
3712 case PF_INET6:
3713 ret = selinux_parse_skb_ipv6(skb, ad, proto);
3714 if (ret)
3715 goto parse_error;
3716 addrp = (char *)(src ? &ad->u.net->v6info.saddr :
3717 &ad->u.net->v6info.daddr);
3718 goto okay;
3719 #endif /* IPV6 */
3720 default:
3721 addrp = NULL;
3722 goto okay;
3723 }
3724
3725 parse_error:
3726 printk(KERN_WARNING
3727 "SELinux: failure in selinux_parse_skb(),"
3728 " unable to parse packet\n");
3729 return ret;
3730
3731 okay:
3732 if (_addrp)
3733 *_addrp = addrp;
3734 return 0;
3735 }
3736
3737 /**
3738 * selinux_skb_peerlbl_sid - Determine the peer label of a packet
3739 * @skb: the packet
3740 * @family: protocol family
3741 * @sid: the packet's peer label SID
3742 *
3743 * Description:
3744 * Check the various different forms of network peer labeling and determine
3745 * the peer label/SID for the packet; most of the magic actually occurs in
3746 * the security server function security_net_peersid_cmp(). The function
3747 * returns zero if the value in @sid is valid (although it may be SECSID_NULL)
3748 * or -EACCES if @sid is invalid due to inconsistencies with the different
3749 * peer labels.
3750 *
3751 */
3752 static int selinux_skb_peerlbl_sid(struct sk_buff *skb, u16 family, u32 *sid)
3753 {
3754 int err;
3755 u32 xfrm_sid;
3756 u32 nlbl_sid;
3757 u32 nlbl_type;
3758
3759 selinux_skb_xfrm_sid(skb, &xfrm_sid);
3760 selinux_netlbl_skbuff_getsid(skb, family, &nlbl_type, &nlbl_sid);
3761
3762 err = security_net_peersid_resolve(nlbl_sid, nlbl_type, xfrm_sid, sid);
3763 if (unlikely(err)) {
3764 printk(KERN_WARNING
3765 "SELinux: failure in selinux_skb_peerlbl_sid(),"
3766 " unable to determine packet's peer label\n");
3767 return -EACCES;
3768 }
3769
3770 return 0;
3771 }
3772
3773 /* socket security operations */
3774
3775 static int socket_sockcreate_sid(const struct task_security_struct *tsec,
3776 u16 secclass, u32 *socksid)
3777 {
3778 if (tsec->sockcreate_sid > SECSID_NULL) {
3779 *socksid = tsec->sockcreate_sid;
3780 return 0;
3781 }
3782
3783 return security_transition_sid(tsec->sid, tsec->sid, secclass, NULL,
3784 socksid);
3785 }
3786
3787 static int sock_has_perm(struct task_struct *task, struct sock *sk, u32 perms)
3788 {
3789 struct sk_security_struct *sksec = sk->sk_security;
3790 struct common_audit_data ad;
3791 struct lsm_network_audit net = {0,};
3792 u32 tsid = task_sid(task);
3793
3794 if (sksec->sid == SECINITSID_KERNEL)
3795 return 0;
3796
3797 ad.type = LSM_AUDIT_DATA_NET;
3798 ad.u.net = &net;
3799 ad.u.net->sk = sk;
3800
3801 return avc_has_perm(tsid, sksec->sid, sksec->sclass, perms, &ad);
3802 }
3803
3804 static int selinux_socket_create(int family, int type,
3805 int protocol, int kern)
3806 {
3807 const struct task_security_struct *tsec = current_security();
3808 u32 newsid;
3809 u16 secclass;
3810 int rc;
3811
3812 if (kern)
3813 return 0;
3814
3815 secclass = socket_type_to_security_class(family, type, protocol);
3816 rc = socket_sockcreate_sid(tsec, secclass, &newsid);
3817 if (rc)
3818 return rc;
3819
3820 return avc_has_perm(tsec->sid, newsid, secclass, SOCKET__CREATE, NULL);
3821 }
3822
3823 static int selinux_socket_post_create(struct socket *sock, int family,
3824 int type, int protocol, int kern)
3825 {
3826 const struct task_security_struct *tsec = current_security();
3827 struct inode_security_struct *isec = SOCK_INODE(sock)->i_security;
3828 struct sk_security_struct *sksec;
3829 int err = 0;
3830
3831 isec->sclass = socket_type_to_security_class(family, type, protocol);
3832
3833 if (kern)
3834 isec->sid = SECINITSID_KERNEL;
3835 else {
3836 err = socket_sockcreate_sid(tsec, isec->sclass, &(isec->sid));
3837 if (err)
3838 return err;
3839 }
3840
3841 isec->initialized = 1;
3842
3843 if (sock->sk) {
3844 sksec = sock->sk->sk_security;
3845 sksec->sid = isec->sid;
3846 sksec->sclass = isec->sclass;
3847 err = selinux_netlbl_socket_post_create(sock->sk, family);
3848 }
3849
3850 return err;
3851 }
3852
3853 /* Range of port numbers used to automatically bind.
3854 Need to determine whether we should perform a name_bind
3855 permission check between the socket and the port number. */
3856
3857 static int selinux_socket_bind(struct socket *sock, struct sockaddr *address, int addrlen)
3858 {
3859 struct sock *sk = sock->sk;
3860 u16 family;
3861 int err;
3862
3863 err = sock_has_perm(current, sk, SOCKET__BIND);
3864 if (err)
3865 goto out;
3866
3867 /*
3868 * If PF_INET or PF_INET6, check name_bind permission for the port.
3869 * Multiple address binding for SCTP is not supported yet: we just
3870 * check the first address now.
3871 */
3872 family = sk->sk_family;
3873 if (family == PF_INET || family == PF_INET6) {
3874 char *addrp;
3875 struct sk_security_struct *sksec = sk->sk_security;
3876 struct common_audit_data ad;
3877 struct lsm_network_audit net = {0,};
3878 struct sockaddr_in *addr4 = NULL;
3879 struct sockaddr_in6 *addr6 = NULL;
3880 unsigned short snum;
3881 u32 sid, node_perm;
3882
3883 if (family == PF_INET) {
3884 addr4 = (struct sockaddr_in *)address;
3885 snum = ntohs(addr4->sin_port);
3886 addrp = (char *)&addr4->sin_addr.s_addr;
3887 } else {
3888 addr6 = (struct sockaddr_in6 *)address;
3889 snum = ntohs(addr6->sin6_port);
3890 addrp = (char *)&addr6->sin6_addr.s6_addr;
3891 }
3892
3893 if (snum) {
3894 int low, high;
3895
3896 inet_get_local_port_range(&low, &high);
3897
3898 if (snum < max(PROT_SOCK, low) || snum > high) {
3899 err = sel_netport_sid(sk->sk_protocol,
3900 snum, &sid);
3901 if (err)
3902 goto out;
3903 ad.type = LSM_AUDIT_DATA_NET;
3904 ad.u.net = &net;
3905 ad.u.net->sport = htons(snum);
3906 ad.u.net->family = family;
3907 err = avc_has_perm(sksec->sid, sid,
3908 sksec->sclass,
3909 SOCKET__NAME_BIND, &ad);
3910 if (err)
3911 goto out;
3912 }
3913 }
3914
3915 switch (sksec->sclass) {
3916 case SECCLASS_TCP_SOCKET:
3917 node_perm = TCP_SOCKET__NODE_BIND;
3918 break;
3919
3920 case SECCLASS_UDP_SOCKET:
3921 node_perm = UDP_SOCKET__NODE_BIND;
3922 break;
3923
3924 case SECCLASS_DCCP_SOCKET:
3925 node_perm = DCCP_SOCKET__NODE_BIND;
3926 break;
3927
3928 default:
3929 node_perm = RAWIP_SOCKET__NODE_BIND;
3930 break;
3931 }
3932
3933 err = sel_netnode_sid(addrp, family, &sid);
3934 if (err)
3935 goto out;
3936
3937 ad.type = LSM_AUDIT_DATA_NET;
3938 ad.u.net = &net;
3939 ad.u.net->sport = htons(snum);
3940 ad.u.net->family = family;
3941
3942 if (family == PF_INET)
3943 ad.u.net->v4info.saddr = addr4->sin_addr.s_addr;
3944 else
3945 ad.u.net->v6info.saddr = addr6->sin6_addr;
3946
3947 err = avc_has_perm(sksec->sid, sid,
3948 sksec->sclass, node_perm, &ad);
3949 if (err)
3950 goto out;
3951 }
3952 out:
3953 return err;
3954 }
3955
3956 static int selinux_socket_connect(struct socket *sock, struct sockaddr *address, int addrlen)
3957 {
3958 struct sock *sk = sock->sk;
3959 struct sk_security_struct *sksec = sk->sk_security;
3960 int err;
3961
3962 err = sock_has_perm(current, sk, SOCKET__CONNECT);
3963 if (err)
3964 return err;
3965
3966 /*
3967 * If a TCP or DCCP socket, check name_connect permission for the port.
3968 */
3969 if (sksec->sclass == SECCLASS_TCP_SOCKET ||
3970 sksec->sclass == SECCLASS_DCCP_SOCKET) {
3971 struct common_audit_data ad;
3972 struct lsm_network_audit net = {0,};
3973 struct sockaddr_in *addr4 = NULL;
3974 struct sockaddr_in6 *addr6 = NULL;
3975 unsigned short snum;
3976 u32 sid, perm;
3977
3978 if (sk->sk_family == PF_INET) {
3979 addr4 = (struct sockaddr_in *)address;
3980 if (addrlen < sizeof(struct sockaddr_in))
3981 return -EINVAL;
3982 snum = ntohs(addr4->sin_port);
3983 } else {
3984 addr6 = (struct sockaddr_in6 *)address;
3985 if (addrlen < SIN6_LEN_RFC2133)
3986 return -EINVAL;
3987 snum = ntohs(addr6->sin6_port);
3988 }
3989
3990 err = sel_netport_sid(sk->sk_protocol, snum, &sid);
3991 if (err)
3992 goto out;
3993
3994 perm = (sksec->sclass == SECCLASS_TCP_SOCKET) ?
3995 TCP_SOCKET__NAME_CONNECT : DCCP_SOCKET__NAME_CONNECT;
3996
3997 ad.type = LSM_AUDIT_DATA_NET;
3998 ad.u.net = &net;
3999 ad.u.net->dport = htons(snum);
4000 ad.u.net->family = sk->sk_family;
4001 err = avc_has_perm(sksec->sid, sid, sksec->sclass, perm, &ad);
4002 if (err)
4003 goto out;
4004 }
4005
4006 err = selinux_netlbl_socket_connect(sk, address);
4007
4008 out:
4009 return err;
4010 }
4011
4012 static int selinux_socket_listen(struct socket *sock, int backlog)
4013 {
4014 return sock_has_perm(current, sock->sk, SOCKET__LISTEN);
4015 }
4016
4017 static int selinux_socket_accept(struct socket *sock, struct socket *newsock)
4018 {
4019 int err;
4020 struct inode_security_struct *isec;
4021 struct inode_security_struct *newisec;
4022
4023 err = sock_has_perm(current, sock->sk, SOCKET__ACCEPT);
4024 if (err)
4025 return err;
4026
4027 newisec = SOCK_INODE(newsock)->i_security;
4028
4029 isec = SOCK_INODE(sock)->i_security;
4030 newisec->sclass = isec->sclass;
4031 newisec->sid = isec->sid;
4032 newisec->initialized = 1;
4033
4034 return 0;
4035 }
4036
4037 static int selinux_socket_sendmsg(struct socket *sock, struct msghdr *msg,
4038 int size)
4039 {
4040 return sock_has_perm(current, sock->sk, SOCKET__WRITE);
4041 }
4042
4043 static int selinux_socket_recvmsg(struct socket *sock, struct msghdr *msg,
4044 int size, int flags)
4045 {
4046 return sock_has_perm(current, sock->sk, SOCKET__READ);
4047 }
4048
4049 static int selinux_socket_getsockname(struct socket *sock)
4050 {
4051 return sock_has_perm(current, sock->sk, SOCKET__GETATTR);
4052 }
4053
4054 static int selinux_socket_getpeername(struct socket *sock)
4055 {
4056 return sock_has_perm(current, sock->sk, SOCKET__GETATTR);
4057 }
4058
4059 static int selinux_socket_setsockopt(struct socket *sock, int level, int optname)
4060 {
4061 int err;
4062
4063 err = sock_has_perm(current, sock->sk, SOCKET__SETOPT);
4064 if (err)
4065 return err;
4066
4067 return selinux_netlbl_socket_setsockopt(sock, level, optname);
4068 }
4069
4070 static int selinux_socket_getsockopt(struct socket *sock, int level,
4071 int optname)
4072 {
4073 return sock_has_perm(current, sock->sk, SOCKET__GETOPT);
4074 }
4075
4076 static int selinux_socket_shutdown(struct socket *sock, int how)
4077 {
4078 return sock_has_perm(current, sock->sk, SOCKET__SHUTDOWN);
4079 }
4080
4081 static int selinux_socket_unix_stream_connect(struct sock *sock,
4082 struct sock *other,
4083 struct sock *newsk)
4084 {
4085 struct sk_security_struct *sksec_sock = sock->sk_security;
4086 struct sk_security_struct *sksec_other = other->sk_security;
4087 struct sk_security_struct *sksec_new = newsk->sk_security;
4088 struct common_audit_data ad;
4089 struct lsm_network_audit net = {0,};
4090 int err;
4091
4092 ad.type = LSM_AUDIT_DATA_NET;
4093 ad.u.net = &net;
4094 ad.u.net->sk = other;
4095
4096 err = avc_has_perm(sksec_sock->sid, sksec_other->sid,
4097 sksec_other->sclass,
4098 UNIX_STREAM_SOCKET__CONNECTTO, &ad);
4099 if (err)
4100 return err;
4101
4102 /* server child socket */
4103 sksec_new->peer_sid = sksec_sock->sid;
4104 err = security_sid_mls_copy(sksec_other->sid, sksec_sock->sid,
4105 &sksec_new->sid);
4106 if (err)
4107 return err;
4108
4109 /* connecting socket */
4110 sksec_sock->peer_sid = sksec_new->sid;
4111
4112 return 0;
4113 }
4114
4115 static int selinux_socket_unix_may_send(struct socket *sock,
4116 struct socket *other)
4117 {
4118 struct sk_security_struct *ssec = sock->sk->sk_security;
4119 struct sk_security_struct *osec = other->sk->sk_security;
4120 struct common_audit_data ad;
4121 struct lsm_network_audit net = {0,};
4122
4123 ad.type = LSM_AUDIT_DATA_NET;
4124 ad.u.net = &net;
4125 ad.u.net->sk = other->sk;
4126
4127 return avc_has_perm(ssec->sid, osec->sid, osec->sclass, SOCKET__SENDTO,
4128 &ad);
4129 }
4130
4131 static int selinux_inet_sys_rcv_skb(int ifindex, char *addrp, u16 family,
4132 u32 peer_sid,
4133 struct common_audit_data *ad)
4134 {
4135 int err;
4136 u32 if_sid;
4137 u32 node_sid;
4138
4139 err = sel_netif_sid(ifindex, &if_sid);
4140 if (err)
4141 return err;
4142 err = avc_has_perm(peer_sid, if_sid,
4143 SECCLASS_NETIF, NETIF__INGRESS, ad);
4144 if (err)
4145 return err;
4146
4147 err = sel_netnode_sid(addrp, family, &node_sid);
4148 if (err)
4149 return err;
4150 return avc_has_perm(peer_sid, node_sid,
4151 SECCLASS_NODE, NODE__RECVFROM, ad);
4152 }
4153
4154 static int selinux_sock_rcv_skb_compat(struct sock *sk, struct sk_buff *skb,
4155 u16 family)
4156 {
4157 int err = 0;
4158 struct sk_security_struct *sksec = sk->sk_security;
4159 u32 sk_sid = sksec->sid;
4160 struct common_audit_data ad;
4161 struct lsm_network_audit net = {0,};
4162 char *addrp;
4163
4164 ad.type = LSM_AUDIT_DATA_NET;
4165 ad.u.net = &net;
4166 ad.u.net->netif = skb->skb_iif;
4167 ad.u.net->family = family;
4168 err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL);
4169 if (err)
4170 return err;
4171
4172 if (selinux_secmark_enabled()) {
4173 err = avc_has_perm(sk_sid, skb->secmark, SECCLASS_PACKET,
4174 PACKET__RECV, &ad);
4175 if (err)
4176 return err;
4177 }
4178
4179 err = selinux_netlbl_sock_rcv_skb(sksec, skb, family, &ad);
4180 if (err)
4181 return err;
4182 err = selinux_xfrm_sock_rcv_skb(sksec->sid, skb, &ad);
4183
4184 return err;
4185 }
4186
4187 static int selinux_socket_sock_rcv_skb(struct sock *sk, struct sk_buff *skb)
4188 {
4189 int err;
4190 struct sk_security_struct *sksec = sk->sk_security;
4191 u16 family = sk->sk_family;
4192 u32 sk_sid = sksec->sid;
4193 struct common_audit_data ad;
4194 struct lsm_network_audit net = {0,};
4195 char *addrp;
4196 u8 secmark_active;
4197 u8 peerlbl_active;
4198
4199 if (family != PF_INET && family != PF_INET6)
4200 return 0;
4201
4202 /* Handle mapped IPv4 packets arriving via IPv6 sockets */
4203 if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
4204 family = PF_INET;
4205
4206 /* If any sort of compatibility mode is enabled then handoff processing
4207 * to the selinux_sock_rcv_skb_compat() function to deal with the
4208 * special handling. We do this in an attempt to keep this function
4209 * as fast and as clean as possible. */
4210 if (!selinux_policycap_netpeer)
4211 return selinux_sock_rcv_skb_compat(sk, skb, family);
4212
4213 secmark_active = selinux_secmark_enabled();
4214 peerlbl_active = netlbl_enabled() || selinux_xfrm_enabled();
4215 if (!secmark_active && !peerlbl_active)
4216 return 0;
4217
4218 ad.type = LSM_AUDIT_DATA_NET;
4219 ad.u.net = &net;
4220 ad.u.net->netif = skb->skb_iif;
4221 ad.u.net->family = family;
4222 err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL);
4223 if (err)
4224 return err;
4225
4226 if (peerlbl_active) {
4227 u32 peer_sid;
4228
4229 err = selinux_skb_peerlbl_sid(skb, family, &peer_sid);
4230 if (err)
4231 return err;
4232 err = selinux_inet_sys_rcv_skb(skb->skb_iif, addrp, family,
4233 peer_sid, &ad);
4234 if (err) {
4235 selinux_netlbl_err(skb, err, 0);
4236 return err;
4237 }
4238 err = avc_has_perm(sk_sid, peer_sid, SECCLASS_PEER,
4239 PEER__RECV, &ad);
4240 if (err)
4241 selinux_netlbl_err(skb, err, 0);
4242 }
4243
4244 if (secmark_active) {
4245 err = avc_has_perm(sk_sid, skb->secmark, SECCLASS_PACKET,
4246 PACKET__RECV, &ad);
4247 if (err)
4248 return err;
4249 }
4250
4251 return err;
4252 }
4253
4254 static int selinux_socket_getpeersec_stream(struct socket *sock, char __user *optval,
4255 int __user *optlen, unsigned len)
4256 {
4257 int err = 0;
4258 char *scontext;
4259 u32 scontext_len;
4260 struct sk_security_struct *sksec = sock->sk->sk_security;
4261 u32 peer_sid = SECSID_NULL;
4262
4263 if (sksec->sclass == SECCLASS_UNIX_STREAM_SOCKET ||
4264 sksec->sclass == SECCLASS_TCP_SOCKET)
4265 peer_sid = sksec->peer_sid;
4266 if (peer_sid == SECSID_NULL)
4267 return -ENOPROTOOPT;
4268
4269 err = security_sid_to_context(peer_sid, &scontext, &scontext_len);
4270 if (err)
4271 return err;
4272
4273 if (scontext_len > len) {
4274 err = -ERANGE;
4275 goto out_len;
4276 }
4277
4278 if (copy_to_user(optval, scontext, scontext_len))
4279 err = -EFAULT;
4280
4281 out_len:
4282 if (put_user(scontext_len, optlen))
4283 err = -EFAULT;
4284 kfree(scontext);
4285 return err;
4286 }
4287
4288 static int selinux_socket_getpeersec_dgram(struct socket *sock, struct sk_buff *skb, u32 *secid)
4289 {
4290 u32 peer_secid = SECSID_NULL;
4291 u16 family;
4292
4293 if (skb && skb->protocol == htons(ETH_P_IP))
4294 family = PF_INET;
4295 else if (skb && skb->protocol == htons(ETH_P_IPV6))
4296 family = PF_INET6;
4297 else if (sock)
4298 family = sock->sk->sk_family;
4299 else
4300 goto out;
4301
4302 if (sock && family == PF_UNIX)
4303 selinux_inode_getsecid(SOCK_INODE(sock), &peer_secid);
4304 else if (skb)
4305 selinux_skb_peerlbl_sid(skb, family, &peer_secid);
4306
4307 out:
4308 *secid = peer_secid;
4309 if (peer_secid == SECSID_NULL)
4310 return -EINVAL;
4311 return 0;
4312 }
4313
4314 static int selinux_sk_alloc_security(struct sock *sk, int family, gfp_t priority)
4315 {
4316 struct sk_security_struct *sksec;
4317
4318 sksec = kzalloc(sizeof(*sksec), priority);
4319 if (!sksec)
4320 return -ENOMEM;
4321
4322 sksec->peer_sid = SECINITSID_UNLABELED;
4323 sksec->sid = SECINITSID_UNLABELED;
4324 selinux_netlbl_sk_security_reset(sksec);
4325 sk->sk_security = sksec;
4326
4327 return 0;
4328 }
4329
4330 static void selinux_sk_free_security(struct sock *sk)
4331 {
4332 struct sk_security_struct *sksec = sk->sk_security;
4333
4334 sk->sk_security = NULL;
4335 selinux_netlbl_sk_security_free(sksec);
4336 kfree(sksec);
4337 }
4338
4339 static void selinux_sk_clone_security(const struct sock *sk, struct sock *newsk)
4340 {
4341 struct sk_security_struct *sksec = sk->sk_security;
4342 struct sk_security_struct *newsksec = newsk->sk_security;
4343
4344 newsksec->sid = sksec->sid;
4345 newsksec->peer_sid = sksec->peer_sid;
4346 newsksec->sclass = sksec->sclass;
4347
4348 selinux_netlbl_sk_security_reset(newsksec);
4349 }
4350
4351 static void selinux_sk_getsecid(struct sock *sk, u32 *secid)
4352 {
4353 if (!sk)
4354 *secid = SECINITSID_ANY_SOCKET;
4355 else {
4356 struct sk_security_struct *sksec = sk->sk_security;
4357
4358 *secid = sksec->sid;
4359 }
4360 }
4361
4362 static void selinux_sock_graft(struct sock *sk, struct socket *parent)
4363 {
4364 struct inode_security_struct *isec = SOCK_INODE(parent)->i_security;
4365 struct sk_security_struct *sksec = sk->sk_security;
4366
4367 if (sk->sk_family == PF_INET || sk->sk_family == PF_INET6 ||
4368 sk->sk_family == PF_UNIX)
4369 isec->sid = sksec->sid;
4370 sksec->sclass = isec->sclass;
4371 }
4372
4373 static int selinux_inet_conn_request(struct sock *sk, struct sk_buff *skb,
4374 struct request_sock *req)
4375 {
4376 struct sk_security_struct *sksec = sk->sk_security;
4377 int err;
4378 u16 family = sk->sk_family;
4379 u32 newsid;
4380 u32 peersid;
4381
4382 /* handle mapped IPv4 packets arriving via IPv6 sockets */
4383 if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
4384 family = PF_INET;
4385
4386 err = selinux_skb_peerlbl_sid(skb, family, &peersid);
4387 if (err)
4388 return err;
4389 if (peersid == SECSID_NULL) {
4390 req->secid = sksec->sid;
4391 req->peer_secid = SECSID_NULL;
4392 } else {
4393 err = security_sid_mls_copy(sksec->sid, peersid, &newsid);
4394 if (err)
4395 return err;
4396 req->secid = newsid;
4397 req->peer_secid = peersid;
4398 }
4399
4400 return selinux_netlbl_inet_conn_request(req, family);
4401 }
4402
4403 static void selinux_inet_csk_clone(struct sock *newsk,
4404 const struct request_sock *req)
4405 {
4406 struct sk_security_struct *newsksec = newsk->sk_security;
4407
4408 newsksec->sid = req->secid;
4409 newsksec->peer_sid = req->peer_secid;
4410 /* NOTE: Ideally, we should also get the isec->sid for the
4411 new socket in sync, but we don't have the isec available yet.
4412 So we will wait until sock_graft to do it, by which
4413 time it will have been created and available. */
4414
4415 /* We don't need to take any sort of lock here as we are the only
4416 * thread with access to newsksec */
4417 selinux_netlbl_inet_csk_clone(newsk, req->rsk_ops->family);
4418 }
4419
4420 static void selinux_inet_conn_established(struct sock *sk, struct sk_buff *skb)
4421 {
4422 u16 family = sk->sk_family;
4423 struct sk_security_struct *sksec = sk->sk_security;
4424
4425 /* handle mapped IPv4 packets arriving via IPv6 sockets */
4426 if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
4427 family = PF_INET;
4428
4429 selinux_skb_peerlbl_sid(skb, family, &sksec->peer_sid);
4430 }
4431
4432 static void selinux_skb_owned_by(struct sk_buff *skb, struct sock *sk)
4433 {
4434 skb_set_owner_w(skb, sk);
4435 }
4436
4437 static int selinux_secmark_relabel_packet(u32 sid)
4438 {
4439 const struct task_security_struct *__tsec;
4440 u32 tsid;
4441
4442 __tsec = current_security();
4443 tsid = __tsec->sid;
4444
4445 return avc_has_perm(tsid, sid, SECCLASS_PACKET, PACKET__RELABELTO, NULL);
4446 }
4447
4448 static void selinux_secmark_refcount_inc(void)
4449 {
4450 atomic_inc(&selinux_secmark_refcount);
4451 }
4452
4453 static void selinux_secmark_refcount_dec(void)
4454 {
4455 atomic_dec(&selinux_secmark_refcount);
4456 }
4457
4458 static void selinux_req_classify_flow(const struct request_sock *req,
4459 struct flowi *fl)
4460 {
4461 fl->flowi_secid = req->secid;
4462 }
4463
4464 static int selinux_tun_dev_alloc_security(void **security)
4465 {
4466 struct tun_security_struct *tunsec;
4467
4468 tunsec = kzalloc(sizeof(*tunsec), GFP_KERNEL);
4469 if (!tunsec)
4470 return -ENOMEM;
4471 tunsec->sid = current_sid();
4472
4473 *security = tunsec;
4474 return 0;
4475 }
4476
4477 static void selinux_tun_dev_free_security(void *security)
4478 {
4479 kfree(security);
4480 }
4481
4482 static int selinux_tun_dev_create(void)
4483 {
4484 u32 sid = current_sid();
4485
4486 /* we aren't taking into account the "sockcreate" SID since the socket
4487 * that is being created here is not a socket in the traditional sense,
4488 * instead it is a private sock, accessible only to the kernel, and
4489 * representing a wide range of network traffic spanning multiple
4490 * connections unlike traditional sockets - check the TUN driver to
4491 * get a better understanding of why this socket is special */
4492
4493 return avc_has_perm(sid, sid, SECCLASS_TUN_SOCKET, TUN_SOCKET__CREATE,
4494 NULL);
4495 }
4496
4497 static int selinux_tun_dev_attach_queue(void *security)
4498 {
4499 struct tun_security_struct *tunsec = security;
4500
4501 return avc_has_perm(current_sid(), tunsec->sid, SECCLASS_TUN_SOCKET,
4502 TUN_SOCKET__ATTACH_QUEUE, NULL);
4503 }
4504
4505 static int selinux_tun_dev_attach(struct sock *sk, void *security)
4506 {
4507 struct tun_security_struct *tunsec = security;
4508 struct sk_security_struct *sksec = sk->sk_security;
4509
4510 /* we don't currently perform any NetLabel based labeling here and it
4511 * isn't clear that we would want to do so anyway; while we could apply
4512 * labeling without the support of the TUN user the resulting labeled
4513 * traffic from the other end of the connection would almost certainly
4514 * cause confusion to the TUN user that had no idea network labeling
4515 * protocols were being used */
4516
4517 sksec->sid = tunsec->sid;
4518 sksec->sclass = SECCLASS_TUN_SOCKET;
4519
4520 return 0;
4521 }
4522
4523 static int selinux_tun_dev_open(void *security)
4524 {
4525 struct tun_security_struct *tunsec = security;
4526 u32 sid = current_sid();
4527 int err;
4528
4529 err = avc_has_perm(sid, tunsec->sid, SECCLASS_TUN_SOCKET,
4530 TUN_SOCKET__RELABELFROM, NULL);
4531 if (err)
4532 return err;
4533 err = avc_has_perm(sid, sid, SECCLASS_TUN_SOCKET,
4534 TUN_SOCKET__RELABELTO, NULL);
4535 if (err)
4536 return err;
4537 tunsec->sid = sid;
4538
4539 return 0;
4540 }
4541
4542 static int selinux_nlmsg_perm(struct sock *sk, struct sk_buff *skb)
4543 {
4544 int err = 0;
4545 u32 perm;
4546 struct nlmsghdr *nlh;
4547 struct sk_security_struct *sksec = sk->sk_security;
4548
4549 if (skb->len < NLMSG_HDRLEN) {
4550 err = -EINVAL;
4551 goto out;
4552 }
4553 nlh = nlmsg_hdr(skb);
4554
4555 err = selinux_nlmsg_lookup(sksec->sclass, nlh->nlmsg_type, &perm);
4556 if (err) {
4557 if (err == -EINVAL) {
4558 audit_log(current->audit_context, GFP_KERNEL, AUDIT_SELINUX_ERR,
4559 "SELinux: unrecognized netlink message"
4560 " type=%hu for sclass=%hu\n",
4561 nlh->nlmsg_type, sksec->sclass);
4562 if (!selinux_enforcing || security_get_allow_unknown())
4563 err = 0;
4564 }
4565
4566 /* Ignore */
4567 if (err == -ENOENT)
4568 err = 0;
4569 goto out;
4570 }
4571
4572 err = sock_has_perm(current, sk, perm);
4573 out:
4574 return err;
4575 }
4576
4577 #ifdef CONFIG_NETFILTER
4578
4579 static unsigned int selinux_ip_forward(struct sk_buff *skb, int ifindex,
4580 u16 family)
4581 {
4582 int err;
4583 char *addrp;
4584 u32 peer_sid;
4585 struct common_audit_data ad;
4586 struct lsm_network_audit net = {0,};
4587 u8 secmark_active;
4588 u8 netlbl_active;
4589 u8 peerlbl_active;
4590
4591 if (!selinux_policycap_netpeer)
4592 return NF_ACCEPT;
4593
4594 secmark_active = selinux_secmark_enabled();
4595 netlbl_active = netlbl_enabled();
4596 peerlbl_active = netlbl_active || selinux_xfrm_enabled();
4597 if (!secmark_active && !peerlbl_active)
4598 return NF_ACCEPT;
4599
4600 if (selinux_skb_peerlbl_sid(skb, family, &peer_sid) != 0)
4601 return NF_DROP;
4602
4603 ad.type = LSM_AUDIT_DATA_NET;
4604 ad.u.net = &net;
4605 ad.u.net->netif = ifindex;
4606 ad.u.net->family = family;
4607 if (selinux_parse_skb(skb, &ad, &addrp, 1, NULL) != 0)
4608 return NF_DROP;
4609
4610 if (peerlbl_active) {
4611 err = selinux_inet_sys_rcv_skb(ifindex, addrp, family,
4612 peer_sid, &ad);
4613 if (err) {
4614 selinux_netlbl_err(skb, err, 1);
4615 return NF_DROP;
4616 }
4617 }
4618
4619 if (secmark_active)
4620 if (avc_has_perm(peer_sid, skb->secmark,
4621 SECCLASS_PACKET, PACKET__FORWARD_IN, &ad))
4622 return NF_DROP;
4623
4624 if (netlbl_active)
4625 /* we do this in the FORWARD path and not the POST_ROUTING
4626 * path because we want to make sure we apply the necessary
4627 * labeling before IPsec is applied so we can leverage AH
4628 * protection */
4629 if (selinux_netlbl_skbuff_setsid(skb, family, peer_sid) != 0)
4630 return NF_DROP;
4631
4632 return NF_ACCEPT;
4633 }
4634
4635 static unsigned int selinux_ipv4_forward(unsigned int hooknum,
4636 struct sk_buff *skb,
4637 const struct net_device *in,
4638 const struct net_device *out,
4639 int (*okfn)(struct sk_buff *))
4640 {
4641 return selinux_ip_forward(skb, in->ifindex, PF_INET);
4642 }
4643
4644 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
4645 static unsigned int selinux_ipv6_forward(unsigned int hooknum,
4646 struct sk_buff *skb,
4647 const struct net_device *in,
4648 const struct net_device *out,
4649 int (*okfn)(struct sk_buff *))
4650 {
4651 return selinux_ip_forward(skb, in->ifindex, PF_INET6);
4652 }
4653 #endif /* IPV6 */
4654
4655 static unsigned int selinux_ip_output(struct sk_buff *skb,
4656 u16 family)
4657 {
4658 u32 sid;
4659
4660 if (!netlbl_enabled())
4661 return NF_ACCEPT;
4662
4663 /* we do this in the LOCAL_OUT path and not the POST_ROUTING path
4664 * because we want to make sure we apply the necessary labeling
4665 * before IPsec is applied so we can leverage AH protection */
4666 if (skb->sk) {
4667 struct sk_security_struct *sksec = skb->sk->sk_security;
4668 sid = sksec->sid;
4669 } else
4670 sid = SECINITSID_KERNEL;
4671 if (selinux_netlbl_skbuff_setsid(skb, family, sid) != 0)
4672 return NF_DROP;
4673
4674 return NF_ACCEPT;
4675 }
4676
4677 static unsigned int selinux_ipv4_output(unsigned int hooknum,
4678 struct sk_buff *skb,
4679 const struct net_device *in,
4680 const struct net_device *out,
4681 int (*okfn)(struct sk_buff *))
4682 {
4683 return selinux_ip_output(skb, PF_INET);
4684 }
4685
4686 static unsigned int selinux_ip_postroute_compat(struct sk_buff *skb,
4687 int ifindex,
4688 u16 family)
4689 {
4690 struct sock *sk = skb->sk;
4691 struct sk_security_struct *sksec;
4692 struct common_audit_data ad;
4693 struct lsm_network_audit net = {0,};
4694 char *addrp;
4695 u8 proto;
4696
4697 if (sk == NULL)
4698 return NF_ACCEPT;
4699 sksec = sk->sk_security;
4700
4701 ad.type = LSM_AUDIT_DATA_NET;
4702 ad.u.net = &net;
4703 ad.u.net->netif = ifindex;
4704 ad.u.net->family = family;
4705 if (selinux_parse_skb(skb, &ad, &addrp, 0, &proto))
4706 return NF_DROP;
4707
4708 if (selinux_secmark_enabled())
4709 if (avc_has_perm(sksec->sid, skb->secmark,
4710 SECCLASS_PACKET, PACKET__SEND, &ad))
4711 return NF_DROP_ERR(-ECONNREFUSED);
4712
4713 if (selinux_xfrm_postroute_last(sksec->sid, skb, &ad, proto))
4714 return NF_DROP_ERR(-ECONNREFUSED);
4715
4716 return NF_ACCEPT;
4717 }
4718
4719 static unsigned int selinux_ip_postroute(struct sk_buff *skb, int ifindex,
4720 u16 family)
4721 {
4722 u32 secmark_perm;
4723 u32 peer_sid;
4724 struct sock *sk;
4725 struct common_audit_data ad;
4726 struct lsm_network_audit net = {0,};
4727 char *addrp;
4728 u8 secmark_active;
4729 u8 peerlbl_active;
4730
4731 /* If any sort of compatibility mode is enabled then handoff processing
4732 * to the selinux_ip_postroute_compat() function to deal with the
4733 * special handling. We do this in an attempt to keep this function
4734 * as fast and as clean as possible. */
4735 if (!selinux_policycap_netpeer)
4736 return selinux_ip_postroute_compat(skb, ifindex, family);
4737 #ifdef CONFIG_XFRM
4738 /* If skb->dst->xfrm is non-NULL then the packet is undergoing an IPsec
4739 * packet transformation so allow the packet to pass without any checks
4740 * since we'll have another chance to perform access control checks
4741 * when the packet is on it's final way out.
4742 * NOTE: there appear to be some IPv6 multicast cases where skb->dst
4743 * is NULL, in this case go ahead and apply access control. */
4744 if (skb_dst(skb) != NULL && skb_dst(skb)->xfrm != NULL)
4745 return NF_ACCEPT;
4746 #endif
4747 secmark_active = selinux_secmark_enabled();
4748 peerlbl_active = netlbl_enabled() || selinux_xfrm_enabled();
4749 if (!secmark_active && !peerlbl_active)
4750 return NF_ACCEPT;
4751
4752 /* if the packet is being forwarded then get the peer label from the
4753 * packet itself; otherwise check to see if it is from a local
4754 * application or the kernel, if from an application get the peer label
4755 * from the sending socket, otherwise use the kernel's sid */
4756 sk = skb->sk;
4757 if (sk == NULL) {
4758 if (skb->skb_iif) {
4759 secmark_perm = PACKET__FORWARD_OUT;
4760 if (selinux_skb_peerlbl_sid(skb, family, &peer_sid))
4761 return NF_DROP;
4762 } else {
4763 secmark_perm = PACKET__SEND;
4764 peer_sid = SECINITSID_KERNEL;
4765 }
4766 } else {
4767 struct sk_security_struct *sksec = sk->sk_security;
4768 peer_sid = sksec->sid;
4769 secmark_perm = PACKET__SEND;
4770 }
4771
4772 ad.type = LSM_AUDIT_DATA_NET;
4773 ad.u.net = &net;
4774 ad.u.net->netif = ifindex;
4775 ad.u.net->family = family;
4776 if (selinux_parse_skb(skb, &ad, &addrp, 0, NULL))
4777 return NF_DROP;
4778
4779 if (secmark_active)
4780 if (avc_has_perm(peer_sid, skb->secmark,
4781 SECCLASS_PACKET, secmark_perm, &ad))
4782 return NF_DROP_ERR(-ECONNREFUSED);
4783
4784 if (peerlbl_active) {
4785 u32 if_sid;
4786 u32 node_sid;
4787
4788 if (sel_netif_sid(ifindex, &if_sid))
4789 return NF_DROP;
4790 if (avc_has_perm(peer_sid, if_sid,
4791 SECCLASS_NETIF, NETIF__EGRESS, &ad))
4792 return NF_DROP_ERR(-ECONNREFUSED);
4793
4794 if (sel_netnode_sid(addrp, family, &node_sid))
4795 return NF_DROP;
4796 if (avc_has_perm(peer_sid, node_sid,
4797 SECCLASS_NODE, NODE__SENDTO, &ad))
4798 return NF_DROP_ERR(-ECONNREFUSED);
4799 }
4800
4801 return NF_ACCEPT;
4802 }
4803
4804 static unsigned int selinux_ipv4_postroute(unsigned int hooknum,
4805 struct sk_buff *skb,
4806 const struct net_device *in,
4807 const struct net_device *out,
4808 int (*okfn)(struct sk_buff *))
4809 {
4810 return selinux_ip_postroute(skb, out->ifindex, PF_INET);
4811 }
4812
4813 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
4814 static unsigned int selinux_ipv6_postroute(unsigned int hooknum,
4815 struct sk_buff *skb,
4816 const struct net_device *in,
4817 const struct net_device *out,
4818 int (*okfn)(struct sk_buff *))
4819 {
4820 return selinux_ip_postroute(skb, out->ifindex, PF_INET6);
4821 }
4822 #endif /* IPV6 */
4823
4824 #endif /* CONFIG_NETFILTER */
4825
4826 static int selinux_netlink_send(struct sock *sk, struct sk_buff *skb)
4827 {
4828 int err;
4829
4830 err = cap_netlink_send(sk, skb);
4831 if (err)
4832 return err;
4833
4834 return selinux_nlmsg_perm(sk, skb);
4835 }
4836
4837 static int ipc_alloc_security(struct task_struct *task,
4838 struct kern_ipc_perm *perm,
4839 u16 sclass)
4840 {
4841 struct ipc_security_struct *isec;
4842 u32 sid;
4843
4844 isec = kzalloc(sizeof(struct ipc_security_struct), GFP_KERNEL);
4845 if (!isec)
4846 return -ENOMEM;
4847
4848 sid = task_sid(task);
4849 isec->sclass = sclass;
4850 isec->sid = sid;
4851 perm->security = isec;
4852
4853 return 0;
4854 }
4855
4856 static void ipc_free_security(struct kern_ipc_perm *perm)
4857 {
4858 struct ipc_security_struct *isec = perm->security;
4859 perm->security = NULL;
4860 kfree(isec);
4861 }
4862
4863 static int msg_msg_alloc_security(struct msg_msg *msg)
4864 {
4865 struct msg_security_struct *msec;
4866
4867 msec = kzalloc(sizeof(struct msg_security_struct), GFP_KERNEL);
4868 if (!msec)
4869 return -ENOMEM;
4870
4871 msec->sid = SECINITSID_UNLABELED;
4872 msg->security = msec;
4873
4874 return 0;
4875 }
4876
4877 static void msg_msg_free_security(struct msg_msg *msg)
4878 {
4879 struct msg_security_struct *msec = msg->security;
4880
4881 msg->security = NULL;
4882 kfree(msec);
4883 }
4884
4885 static int ipc_has_perm(struct kern_ipc_perm *ipc_perms,
4886 u32 perms)
4887 {
4888 struct ipc_security_struct *isec;
4889 struct common_audit_data ad;
4890 u32 sid = current_sid();
4891
4892 isec = ipc_perms->security;
4893
4894 ad.type = LSM_AUDIT_DATA_IPC;
4895 ad.u.ipc_id = ipc_perms->key;
4896
4897 return avc_has_perm(sid, isec->sid, isec->sclass, perms, &ad);
4898 }
4899
4900 static int selinux_msg_msg_alloc_security(struct msg_msg *msg)
4901 {
4902 return msg_msg_alloc_security(msg);
4903 }
4904
4905 static void selinux_msg_msg_free_security(struct msg_msg *msg)
4906 {
4907 msg_msg_free_security(msg);
4908 }
4909
4910 /* message queue security operations */
4911 static int selinux_msg_queue_alloc_security(struct msg_queue *msq)
4912 {
4913 struct ipc_security_struct *isec;
4914 struct common_audit_data ad;
4915 u32 sid = current_sid();
4916 int rc;
4917
4918 rc = ipc_alloc_security(current, &msq->q_perm, SECCLASS_MSGQ);
4919 if (rc)
4920 return rc;
4921
4922 isec = msq->q_perm.security;
4923
4924 ad.type = LSM_AUDIT_DATA_IPC;
4925 ad.u.ipc_id = msq->q_perm.key;
4926
4927 rc = avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
4928 MSGQ__CREATE, &ad);
4929 if (rc) {
4930 ipc_free_security(&msq->q_perm);
4931 return rc;
4932 }
4933 return 0;
4934 }
4935
4936 static void selinux_msg_queue_free_security(struct msg_queue *msq)
4937 {
4938 ipc_free_security(&msq->q_perm);
4939 }
4940
4941 static int selinux_msg_queue_associate(struct msg_queue *msq, int msqflg)
4942 {
4943 struct ipc_security_struct *isec;
4944 struct common_audit_data ad;
4945 u32 sid = current_sid();
4946
4947 isec = msq->q_perm.security;
4948
4949 ad.type = LSM_AUDIT_DATA_IPC;
4950 ad.u.ipc_id = msq->q_perm.key;
4951
4952 return avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
4953 MSGQ__ASSOCIATE, &ad);
4954 }
4955
4956 static int selinux_msg_queue_msgctl(struct msg_queue *msq, int cmd)
4957 {
4958 int err;
4959 int perms;
4960
4961 switch (cmd) {
4962 case IPC_INFO:
4963 case MSG_INFO:
4964 /* No specific object, just general system-wide information. */
4965 return task_has_system(current, SYSTEM__IPC_INFO);
4966 case IPC_STAT:
4967 case MSG_STAT:
4968 perms = MSGQ__GETATTR | MSGQ__ASSOCIATE;
4969 break;
4970 case IPC_SET:
4971 perms = MSGQ__SETATTR;
4972 break;
4973 case IPC_RMID:
4974 perms = MSGQ__DESTROY;
4975 break;
4976 default:
4977 return 0;
4978 }
4979
4980 err = ipc_has_perm(&msq->q_perm, perms);
4981 return err;
4982 }
4983
4984 static int selinux_msg_queue_msgsnd(struct msg_queue *msq, struct msg_msg *msg, int msqflg)
4985 {
4986 struct ipc_security_struct *isec;
4987 struct msg_security_struct *msec;
4988 struct common_audit_data ad;
4989 u32 sid = current_sid();
4990 int rc;
4991
4992 isec = msq->q_perm.security;
4993 msec = msg->security;
4994
4995 /*
4996 * First time through, need to assign label to the message
4997 */
4998 if (msec->sid == SECINITSID_UNLABELED) {
4999 /*
5000 * Compute new sid based on current process and
5001 * message queue this message will be stored in
5002 */
5003 rc = security_transition_sid(sid, isec->sid, SECCLASS_MSG,
5004 NULL, &msec->sid);
5005 if (rc)
5006 return rc;
5007 }
5008
5009 ad.type = LSM_AUDIT_DATA_IPC;
5010 ad.u.ipc_id = msq->q_perm.key;
5011
5012 /* Can this process write to the queue? */
5013 rc = avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
5014 MSGQ__WRITE, &ad);
5015 if (!rc)
5016 /* Can this process send the message */
5017 rc = avc_has_perm(sid, msec->sid, SECCLASS_MSG,
5018 MSG__SEND, &ad);
5019 if (!rc)
5020 /* Can the message be put in the queue? */
5021 rc = avc_has_perm(msec->sid, isec->sid, SECCLASS_MSGQ,
5022 MSGQ__ENQUEUE, &ad);
5023
5024 return rc;
5025 }
5026
5027 static int selinux_msg_queue_msgrcv(struct msg_queue *msq, struct msg_msg *msg,
5028 struct task_struct *target,
5029 long type, int mode)
5030 {
5031 struct ipc_security_struct *isec;
5032 struct msg_security_struct *msec;
5033 struct common_audit_data ad;
5034 u32 sid = task_sid(target);
5035 int rc;
5036
5037 isec = msq->q_perm.security;
5038 msec = msg->security;
5039
5040 ad.type = LSM_AUDIT_DATA_IPC;
5041 ad.u.ipc_id = msq->q_perm.key;
5042
5043 rc = avc_has_perm(sid, isec->sid,
5044 SECCLASS_MSGQ, MSGQ__READ, &ad);
5045 if (!rc)
5046 rc = avc_has_perm(sid, msec->sid,
5047 SECCLASS_MSG, MSG__RECEIVE, &ad);
5048 return rc;
5049 }
5050
5051 /* Shared Memory security operations */
5052 static int selinux_shm_alloc_security(struct shmid_kernel *shp)
5053 {
5054 struct ipc_security_struct *isec;
5055 struct common_audit_data ad;
5056 u32 sid = current_sid();
5057 int rc;
5058
5059 rc = ipc_alloc_security(current, &shp->shm_perm, SECCLASS_SHM);
5060 if (rc)
5061 return rc;
5062
5063 isec = shp->shm_perm.security;
5064
5065 ad.type = LSM_AUDIT_DATA_IPC;
5066 ad.u.ipc_id = shp->shm_perm.key;
5067
5068 rc = avc_has_perm(sid, isec->sid, SECCLASS_SHM,
5069 SHM__CREATE, &ad);
5070 if (rc) {
5071 ipc_free_security(&shp->shm_perm);
5072 return rc;
5073 }
5074 return 0;
5075 }
5076
5077 static void selinux_shm_free_security(struct shmid_kernel *shp)
5078 {
5079 ipc_free_security(&shp->shm_perm);
5080 }
5081
5082 static int selinux_shm_associate(struct shmid_kernel *shp, int shmflg)
5083 {
5084 struct ipc_security_struct *isec;
5085 struct common_audit_data ad;
5086 u32 sid = current_sid();
5087
5088 isec = shp->shm_perm.security;
5089
5090 ad.type = LSM_AUDIT_DATA_IPC;
5091 ad.u.ipc_id = shp->shm_perm.key;
5092
5093 return avc_has_perm(sid, isec->sid, SECCLASS_SHM,
5094 SHM__ASSOCIATE, &ad);
5095 }
5096
5097 /* Note, at this point, shp is locked down */
5098 static int selinux_shm_shmctl(struct shmid_kernel *shp, int cmd)
5099 {
5100 int perms;
5101 int err;
5102
5103 switch (cmd) {
5104 case IPC_INFO:
5105 case SHM_INFO:
5106 /* No specific object, just general system-wide information. */
5107 return task_has_system(current, SYSTEM__IPC_INFO);
5108 case IPC_STAT:
5109 case SHM_STAT:
5110 perms = SHM__GETATTR | SHM__ASSOCIATE;
5111 break;
5112 case IPC_SET:
5113 perms = SHM__SETATTR;
5114 break;
5115 case SHM_LOCK:
5116 case SHM_UNLOCK:
5117 perms = SHM__LOCK;
5118 break;
5119 case IPC_RMID:
5120 perms = SHM__DESTROY;
5121 break;
5122 default:
5123 return 0;
5124 }
5125
5126 err = ipc_has_perm(&shp->shm_perm, perms);
5127 return err;
5128 }
5129
5130 static int selinux_shm_shmat(struct shmid_kernel *shp,
5131 char __user *shmaddr, int shmflg)
5132 {
5133 u32 perms;
5134
5135 if (shmflg & SHM_RDONLY)
5136 perms = SHM__READ;
5137 else
5138 perms = SHM__READ | SHM__WRITE;
5139
5140 return ipc_has_perm(&shp->shm_perm, perms);
5141 }
5142
5143 /* Semaphore security operations */
5144 static int selinux_sem_alloc_security(struct sem_array *sma)
5145 {
5146 struct ipc_security_struct *isec;
5147 struct common_audit_data ad;
5148 u32 sid = current_sid();
5149 int rc;
5150
5151 rc = ipc_alloc_security(current, &sma->sem_perm, SECCLASS_SEM);
5152 if (rc)
5153 return rc;
5154
5155 isec = sma->sem_perm.security;
5156
5157 ad.type = LSM_AUDIT_DATA_IPC;
5158 ad.u.ipc_id = sma->sem_perm.key;
5159
5160 rc = avc_has_perm(sid, isec->sid, SECCLASS_SEM,
5161 SEM__CREATE, &ad);
5162 if (rc) {
5163 ipc_free_security(&sma->sem_perm);
5164 return rc;
5165 }
5166 return 0;
5167 }
5168
5169 static void selinux_sem_free_security(struct sem_array *sma)
5170 {
5171 ipc_free_security(&sma->sem_perm);
5172 }
5173
5174 static int selinux_sem_associate(struct sem_array *sma, int semflg)
5175 {
5176 struct ipc_security_struct *isec;
5177 struct common_audit_data ad;
5178 u32 sid = current_sid();
5179
5180 isec = sma->sem_perm.security;
5181
5182 ad.type = LSM_AUDIT_DATA_IPC;
5183 ad.u.ipc_id = sma->sem_perm.key;
5184
5185 return avc_has_perm(sid, isec->sid, SECCLASS_SEM,
5186 SEM__ASSOCIATE, &ad);
5187 }
5188
5189 /* Note, at this point, sma is locked down */
5190 static int selinux_sem_semctl(struct sem_array *sma, int cmd)
5191 {
5192 int err;
5193 u32 perms;
5194
5195 switch (cmd) {
5196 case IPC_INFO:
5197 case SEM_INFO:
5198 /* No specific object, just general system-wide information. */
5199 return task_has_system(current, SYSTEM__IPC_INFO);
5200 case GETPID:
5201 case GETNCNT:
5202 case GETZCNT:
5203 perms = SEM__GETATTR;
5204 break;
5205 case GETVAL:
5206 case GETALL:
5207 perms = SEM__READ;
5208 break;
5209 case SETVAL:
5210 case SETALL:
5211 perms = SEM__WRITE;
5212 break;
5213 case IPC_RMID:
5214 perms = SEM__DESTROY;
5215 break;
5216 case IPC_SET:
5217 perms = SEM__SETATTR;
5218 break;
5219 case IPC_STAT:
5220 case SEM_STAT:
5221 perms = SEM__GETATTR | SEM__ASSOCIATE;
5222 break;
5223 default:
5224 return 0;
5225 }
5226
5227 err = ipc_has_perm(&sma->sem_perm, perms);
5228 return err;
5229 }
5230
5231 static int selinux_sem_semop(struct sem_array *sma,
5232 struct sembuf *sops, unsigned nsops, int alter)
5233 {
5234 u32 perms;
5235
5236 if (alter)
5237 perms = SEM__READ | SEM__WRITE;
5238 else
5239 perms = SEM__READ;
5240
5241 return ipc_has_perm(&sma->sem_perm, perms);
5242 }
5243
5244 static int selinux_ipc_permission(struct kern_ipc_perm *ipcp, short flag)
5245 {
5246 u32 av = 0;
5247
5248 av = 0;
5249 if (flag & S_IRUGO)
5250 av |= IPC__UNIX_READ;
5251 if (flag & S_IWUGO)
5252 av |= IPC__UNIX_WRITE;
5253
5254 if (av == 0)
5255 return 0;
5256
5257 return ipc_has_perm(ipcp, av);
5258 }
5259
5260 static void selinux_ipc_getsecid(struct kern_ipc_perm *ipcp, u32 *secid)
5261 {
5262 struct ipc_security_struct *isec = ipcp->security;
5263 *secid = isec->sid;
5264 }
5265
5266 static void selinux_d_instantiate(struct dentry *dentry, struct inode *inode)
5267 {
5268 if (inode)
5269 inode_doinit_with_dentry(inode, dentry);
5270 }
5271
5272 static int selinux_getprocattr(struct task_struct *p,
5273 char *name, char **value)
5274 {
5275 const struct task_security_struct *__tsec;
5276 u32 sid;
5277 int error;
5278 unsigned len;
5279
5280 if (current != p) {
5281 error = current_has_perm(p, PROCESS__GETATTR);
5282 if (error)
5283 return error;
5284 }
5285
5286 rcu_read_lock();
5287 __tsec = __task_cred(p)->security;
5288
5289 if (!strcmp(name, "current"))
5290 sid = __tsec->sid;
5291 else if (!strcmp(name, "prev"))
5292 sid = __tsec->osid;
5293 else if (!strcmp(name, "exec"))
5294 sid = __tsec->exec_sid;
5295 else if (!strcmp(name, "fscreate"))
5296 sid = __tsec->create_sid;
5297 else if (!strcmp(name, "keycreate"))
5298 sid = __tsec->keycreate_sid;
5299 else if (!strcmp(name, "sockcreate"))
5300 sid = __tsec->sockcreate_sid;
5301 else
5302 goto invalid;
5303 rcu_read_unlock();
5304
5305 if (!sid)
5306 return 0;
5307
5308 error = security_sid_to_context(sid, value, &len);
5309 if (error)
5310 return error;
5311 return len;
5312
5313 invalid:
5314 rcu_read_unlock();
5315 return -EINVAL;
5316 }
5317
5318 static int selinux_setprocattr(struct task_struct *p,
5319 char *name, void *value, size_t size)
5320 {
5321 struct task_security_struct *tsec;
5322 struct task_struct *tracer;
5323 struct cred *new;
5324 u32 sid = 0, ptsid;
5325 int error;
5326 char *str = value;
5327
5328 if (current != p) {
5329 /* SELinux only allows a process to change its own
5330 security attributes. */
5331 return -EACCES;
5332 }
5333
5334 /*
5335 * Basic control over ability to set these attributes at all.
5336 * current == p, but we'll pass them separately in case the
5337 * above restriction is ever removed.
5338 */
5339 if (!strcmp(name, "exec"))
5340 error = current_has_perm(p, PROCESS__SETEXEC);
5341 else if (!strcmp(name, "fscreate"))
5342 error = current_has_perm(p, PROCESS__SETFSCREATE);
5343 else if (!strcmp(name, "keycreate"))
5344 error = current_has_perm(p, PROCESS__SETKEYCREATE);
5345 else if (!strcmp(name, "sockcreate"))
5346 error = current_has_perm(p, PROCESS__SETSOCKCREATE);
5347 else if (!strcmp(name, "current"))
5348 error = current_has_perm(p, PROCESS__SETCURRENT);
5349 else
5350 error = -EINVAL;
5351 if (error)
5352 return error;
5353
5354 /* Obtain a SID for the context, if one was specified. */
5355 if (size && str[1] && str[1] != '\n') {
5356 if (str[size-1] == '\n') {
5357 str[size-1] = 0;
5358 size--;
5359 }
5360 error = security_context_to_sid(value, size, &sid);
5361 if (error == -EINVAL && !strcmp(name, "fscreate")) {
5362 if (!capable(CAP_MAC_ADMIN)) {
5363 struct audit_buffer *ab;
5364 size_t audit_size;
5365
5366 /* We strip a nul only if it is at the end, otherwise the
5367 * context contains a nul and we should audit that */
5368 if (str[size - 1] == '\0')
5369 audit_size = size - 1;
5370 else
5371 audit_size = size;
5372 ab = audit_log_start(current->audit_context, GFP_ATOMIC, AUDIT_SELINUX_ERR);
5373 audit_log_format(ab, "op=fscreate invalid_context=");
5374 audit_log_n_untrustedstring(ab, value, audit_size);
5375 audit_log_end(ab);
5376
5377 return error;
5378 }
5379 error = security_context_to_sid_force(value, size,
5380 &sid);
5381 }
5382 if (error)
5383 return error;
5384 }
5385
5386 new = prepare_creds();
5387 if (!new)
5388 return -ENOMEM;
5389
5390 /* Permission checking based on the specified context is
5391 performed during the actual operation (execve,
5392 open/mkdir/...), when we know the full context of the
5393 operation. See selinux_bprm_set_creds for the execve
5394 checks and may_create for the file creation checks. The
5395 operation will then fail if the context is not permitted. */
5396 tsec = new->security;
5397 if (!strcmp(name, "exec")) {
5398 tsec->exec_sid = sid;
5399 } else if (!strcmp(name, "fscreate")) {
5400 tsec->create_sid = sid;
5401 } else if (!strcmp(name, "keycreate")) {
5402 error = may_create_key(sid, p);
5403 if (error)
5404 goto abort_change;
5405 tsec->keycreate_sid = sid;
5406 } else if (!strcmp(name, "sockcreate")) {
5407 tsec->sockcreate_sid = sid;
5408 } else if (!strcmp(name, "current")) {
5409 error = -EINVAL;
5410 if (sid == 0)
5411 goto abort_change;
5412
5413 /* Only allow single threaded processes to change context */
5414 error = -EPERM;
5415 if (!current_is_single_threaded()) {
5416 error = security_bounded_transition(tsec->sid, sid);
5417 if (error)
5418 goto abort_change;
5419 }
5420
5421 /* Check permissions for the transition. */
5422 error = avc_has_perm(tsec->sid, sid, SECCLASS_PROCESS,
5423 PROCESS__DYNTRANSITION, NULL);
5424 if (error)
5425 goto abort_change;
5426
5427 /* Check for ptracing, and update the task SID if ok.
5428 Otherwise, leave SID unchanged and fail. */
5429 ptsid = 0;
5430 task_lock(p);
5431 tracer = ptrace_parent(p);
5432 if (tracer)
5433 ptsid = task_sid(tracer);
5434 task_unlock(p);
5435
5436 if (tracer) {
5437 error = avc_has_perm(ptsid, sid, SECCLASS_PROCESS,
5438 PROCESS__PTRACE, NULL);
5439 if (error)
5440 goto abort_change;
5441 }
5442
5443 tsec->sid = sid;
5444 } else {
5445 error = -EINVAL;
5446 goto abort_change;
5447 }
5448
5449 commit_creds(new);
5450 return size;
5451
5452 abort_change:
5453 abort_creds(new);
5454 return error;
5455 }
5456
5457 static int selinux_secid_to_secctx(u32 secid, char **secdata, u32 *seclen)
5458 {
5459 return security_sid_to_context(secid, secdata, seclen);
5460 }
5461
5462 static int selinux_secctx_to_secid(const char *secdata, u32 seclen, u32 *secid)
5463 {
5464 return security_context_to_sid(secdata, seclen, secid);
5465 }
5466
5467 static void selinux_release_secctx(char *secdata, u32 seclen)
5468 {
5469 kfree(secdata);
5470 }
5471
5472 /*
5473 * called with inode->i_mutex locked
5474 */
5475 static int selinux_inode_notifysecctx(struct inode *inode, void *ctx, u32 ctxlen)
5476 {
5477 return selinux_inode_setsecurity(inode, XATTR_SELINUX_SUFFIX, ctx, ctxlen, 0);
5478 }
5479
5480 /*
5481 * called with inode->i_mutex locked
5482 */
5483 static int selinux_inode_setsecctx(struct dentry *dentry, void *ctx, u32 ctxlen)
5484 {
5485 return __vfs_setxattr_noperm(dentry, XATTR_NAME_SELINUX, ctx, ctxlen, 0);
5486 }
5487
5488 static int selinux_inode_getsecctx(struct inode *inode, void **ctx, u32 *ctxlen)
5489 {
5490 int len = 0;
5491 len = selinux_inode_getsecurity(inode, XATTR_SELINUX_SUFFIX,
5492 ctx, true);
5493 if (len < 0)
5494 return len;
5495 *ctxlen = len;
5496 return 0;
5497 }
5498 #ifdef CONFIG_KEYS
5499
5500 static int selinux_key_alloc(struct key *k, const struct cred *cred,
5501 unsigned long flags)
5502 {
5503 const struct task_security_struct *tsec;
5504 struct key_security_struct *ksec;
5505
5506 ksec = kzalloc(sizeof(struct key_security_struct), GFP_KERNEL);
5507 if (!ksec)
5508 return -ENOMEM;
5509
5510 tsec = cred->security;
5511 if (tsec->keycreate_sid)
5512 ksec->sid = tsec->keycreate_sid;
5513 else
5514 ksec->sid = tsec->sid;
5515
5516 k->security = ksec;
5517 return 0;
5518 }
5519
5520 static void selinux_key_free(struct key *k)
5521 {
5522 struct key_security_struct *ksec = k->security;
5523
5524 k->security = NULL;
5525 kfree(ksec);
5526 }
5527
5528 static int selinux_key_permission(key_ref_t key_ref,
5529 const struct cred *cred,
5530 key_perm_t perm)
5531 {
5532 struct key *key;
5533 struct key_security_struct *ksec;
5534 u32 sid;
5535
5536 /* if no specific permissions are requested, we skip the
5537 permission check. No serious, additional covert channels
5538 appear to be created. */
5539 if (perm == 0)
5540 return 0;
5541
5542 sid = cred_sid(cred);
5543
5544 key = key_ref_to_ptr(key_ref);
5545 ksec = key->security;
5546
5547 return avc_has_perm(sid, ksec->sid, SECCLASS_KEY, perm, NULL);
5548 }
5549
5550 static int selinux_key_getsecurity(struct key *key, char **_buffer)
5551 {
5552 struct key_security_struct *ksec = key->security;
5553 char *context = NULL;
5554 unsigned len;
5555 int rc;
5556
5557 rc = security_sid_to_context(ksec->sid, &context, &len);
5558 if (!rc)
5559 rc = len;
5560 *_buffer = context;
5561 return rc;
5562 }
5563
5564 #endif
5565
5566 static struct security_operations selinux_ops = {
5567 .name = "selinux",
5568
5569 .ptrace_access_check = selinux_ptrace_access_check,
5570 .ptrace_traceme = selinux_ptrace_traceme,
5571 .capget = selinux_capget,
5572 .capset = selinux_capset,
5573 .capable = selinux_capable,
5574 .quotactl = selinux_quotactl,
5575 .quota_on = selinux_quota_on,
5576 .syslog = selinux_syslog,
5577 .vm_enough_memory = selinux_vm_enough_memory,
5578
5579 .netlink_send = selinux_netlink_send,
5580
5581 .bprm_set_creds = selinux_bprm_set_creds,
5582 .bprm_committing_creds = selinux_bprm_committing_creds,
5583 .bprm_committed_creds = selinux_bprm_committed_creds,
5584 .bprm_secureexec = selinux_bprm_secureexec,
5585
5586 .sb_alloc_security = selinux_sb_alloc_security,
5587 .sb_free_security = selinux_sb_free_security,
5588 .sb_copy_data = selinux_sb_copy_data,
5589 .sb_remount = selinux_sb_remount,
5590 .sb_kern_mount = selinux_sb_kern_mount,
5591 .sb_show_options = selinux_sb_show_options,
5592 .sb_statfs = selinux_sb_statfs,
5593 .sb_mount = selinux_mount,
5594 .sb_umount = selinux_umount,
5595 .sb_set_mnt_opts = selinux_set_mnt_opts,
5596 .sb_clone_mnt_opts = selinux_sb_clone_mnt_opts,
5597 .sb_parse_opts_str = selinux_parse_opts_str,
5598
5599 .dentry_init_security = selinux_dentry_init_security,
5600
5601 .inode_alloc_security = selinux_inode_alloc_security,
5602 .inode_free_security = selinux_inode_free_security,
5603 .inode_init_security = selinux_inode_init_security,
5604 .inode_create = selinux_inode_create,
5605 .inode_link = selinux_inode_link,
5606 .inode_unlink = selinux_inode_unlink,
5607 .inode_symlink = selinux_inode_symlink,
5608 .inode_mkdir = selinux_inode_mkdir,
5609 .inode_rmdir = selinux_inode_rmdir,
5610 .inode_mknod = selinux_inode_mknod,
5611 .inode_rename = selinux_inode_rename,
5612 .inode_readlink = selinux_inode_readlink,
5613 .inode_follow_link = selinux_inode_follow_link,
5614 .inode_permission = selinux_inode_permission,
5615 .inode_setattr = selinux_inode_setattr,
5616 .inode_getattr = selinux_inode_getattr,
5617 .inode_setxattr = selinux_inode_setxattr,
5618 .inode_post_setxattr = selinux_inode_post_setxattr,
5619 .inode_getxattr = selinux_inode_getxattr,
5620 .inode_listxattr = selinux_inode_listxattr,
5621 .inode_removexattr = selinux_inode_removexattr,
5622 .inode_getsecurity = selinux_inode_getsecurity,
5623 .inode_setsecurity = selinux_inode_setsecurity,
5624 .inode_listsecurity = selinux_inode_listsecurity,
5625 .inode_getsecid = selinux_inode_getsecid,
5626
5627 .file_permission = selinux_file_permission,
5628 .file_alloc_security = selinux_file_alloc_security,
5629 .file_free_security = selinux_file_free_security,
5630 .file_ioctl = selinux_file_ioctl,
5631 .mmap_file = selinux_mmap_file,
5632 .mmap_addr = selinux_mmap_addr,
5633 .file_mprotect = selinux_file_mprotect,
5634 .file_lock = selinux_file_lock,
5635 .file_fcntl = selinux_file_fcntl,
5636 .file_set_fowner = selinux_file_set_fowner,
5637 .file_send_sigiotask = selinux_file_send_sigiotask,
5638 .file_receive = selinux_file_receive,
5639
5640 .file_open = selinux_file_open,
5641
5642 .task_create = selinux_task_create,
5643 .cred_alloc_blank = selinux_cred_alloc_blank,
5644 .cred_free = selinux_cred_free,
5645 .cred_prepare = selinux_cred_prepare,
5646 .cred_transfer = selinux_cred_transfer,
5647 .kernel_act_as = selinux_kernel_act_as,
5648 .kernel_create_files_as = selinux_kernel_create_files_as,
5649 .kernel_module_request = selinux_kernel_module_request,
5650 .task_setpgid = selinux_task_setpgid,
5651 .task_getpgid = selinux_task_getpgid,
5652 .task_getsid = selinux_task_getsid,
5653 .task_getsecid = selinux_task_getsecid,
5654 .task_setnice = selinux_task_setnice,
5655 .task_setioprio = selinux_task_setioprio,
5656 .task_getioprio = selinux_task_getioprio,
5657 .task_setrlimit = selinux_task_setrlimit,
5658 .task_setscheduler = selinux_task_setscheduler,
5659 .task_getscheduler = selinux_task_getscheduler,
5660 .task_movememory = selinux_task_movememory,
5661 .task_kill = selinux_task_kill,
5662 .task_wait = selinux_task_wait,
5663 .task_to_inode = selinux_task_to_inode,
5664
5665 .ipc_permission = selinux_ipc_permission,
5666 .ipc_getsecid = selinux_ipc_getsecid,
5667
5668 .msg_msg_alloc_security = selinux_msg_msg_alloc_security,
5669 .msg_msg_free_security = selinux_msg_msg_free_security,
5670
5671 .msg_queue_alloc_security = selinux_msg_queue_alloc_security,
5672 .msg_queue_free_security = selinux_msg_queue_free_security,
5673 .msg_queue_associate = selinux_msg_queue_associate,
5674 .msg_queue_msgctl = selinux_msg_queue_msgctl,
5675 .msg_queue_msgsnd = selinux_msg_queue_msgsnd,
5676 .msg_queue_msgrcv = selinux_msg_queue_msgrcv,
5677
5678 .shm_alloc_security = selinux_shm_alloc_security,
5679 .shm_free_security = selinux_shm_free_security,
5680 .shm_associate = selinux_shm_associate,
5681 .shm_shmctl = selinux_shm_shmctl,
5682 .shm_shmat = selinux_shm_shmat,
5683
5684 .sem_alloc_security = selinux_sem_alloc_security,
5685 .sem_free_security = selinux_sem_free_security,
5686 .sem_associate = selinux_sem_associate,
5687 .sem_semctl = selinux_sem_semctl,
5688 .sem_semop = selinux_sem_semop,
5689
5690 .d_instantiate = selinux_d_instantiate,
5691
5692 .getprocattr = selinux_getprocattr,
5693 .setprocattr = selinux_setprocattr,
5694
5695 .secid_to_secctx = selinux_secid_to_secctx,
5696 .secctx_to_secid = selinux_secctx_to_secid,
5697 .release_secctx = selinux_release_secctx,
5698 .inode_notifysecctx = selinux_inode_notifysecctx,
5699 .inode_setsecctx = selinux_inode_setsecctx,
5700 .inode_getsecctx = selinux_inode_getsecctx,
5701
5702 .unix_stream_connect = selinux_socket_unix_stream_connect,
5703 .unix_may_send = selinux_socket_unix_may_send,
5704
5705 .socket_create = selinux_socket_create,
5706 .socket_post_create = selinux_socket_post_create,
5707 .socket_bind = selinux_socket_bind,
5708 .socket_connect = selinux_socket_connect,
5709 .socket_listen = selinux_socket_listen,
5710 .socket_accept = selinux_socket_accept,
5711 .socket_sendmsg = selinux_socket_sendmsg,
5712 .socket_recvmsg = selinux_socket_recvmsg,
5713 .socket_getsockname = selinux_socket_getsockname,
5714 .socket_getpeername = selinux_socket_getpeername,
5715 .socket_getsockopt = selinux_socket_getsockopt,
5716 .socket_setsockopt = selinux_socket_setsockopt,
5717 .socket_shutdown = selinux_socket_shutdown,
5718 .socket_sock_rcv_skb = selinux_socket_sock_rcv_skb,
5719 .socket_getpeersec_stream = selinux_socket_getpeersec_stream,
5720 .socket_getpeersec_dgram = selinux_socket_getpeersec_dgram,
5721 .sk_alloc_security = selinux_sk_alloc_security,
5722 .sk_free_security = selinux_sk_free_security,
5723 .sk_clone_security = selinux_sk_clone_security,
5724 .sk_getsecid = selinux_sk_getsecid,
5725 .sock_graft = selinux_sock_graft,
5726 .inet_conn_request = selinux_inet_conn_request,
5727 .inet_csk_clone = selinux_inet_csk_clone,
5728 .inet_conn_established = selinux_inet_conn_established,
5729 .secmark_relabel_packet = selinux_secmark_relabel_packet,
5730 .secmark_refcount_inc = selinux_secmark_refcount_inc,
5731 .secmark_refcount_dec = selinux_secmark_refcount_dec,
5732 .req_classify_flow = selinux_req_classify_flow,
5733 .tun_dev_alloc_security = selinux_tun_dev_alloc_security,
5734 .tun_dev_free_security = selinux_tun_dev_free_security,
5735 .tun_dev_create = selinux_tun_dev_create,
5736 .tun_dev_attach_queue = selinux_tun_dev_attach_queue,
5737 .tun_dev_attach = selinux_tun_dev_attach,
5738 .tun_dev_open = selinux_tun_dev_open,
5739 .skb_owned_by = selinux_skb_owned_by,
5740
5741 #ifdef CONFIG_SECURITY_NETWORK_XFRM
5742 .xfrm_policy_alloc_security = selinux_xfrm_policy_alloc,
5743 .xfrm_policy_clone_security = selinux_xfrm_policy_clone,
5744 .xfrm_policy_free_security = selinux_xfrm_policy_free,
5745 .xfrm_policy_delete_security = selinux_xfrm_policy_delete,
5746 .xfrm_state_alloc_security = selinux_xfrm_state_alloc,
5747 .xfrm_state_free_security = selinux_xfrm_state_free,
5748 .xfrm_state_delete_security = selinux_xfrm_state_delete,
5749 .xfrm_policy_lookup = selinux_xfrm_policy_lookup,
5750 .xfrm_state_pol_flow_match = selinux_xfrm_state_pol_flow_match,
5751 .xfrm_decode_session = selinux_xfrm_decode_session,
5752 #endif
5753
5754 #ifdef CONFIG_KEYS
5755 .key_alloc = selinux_key_alloc,
5756 .key_free = selinux_key_free,
5757 .key_permission = selinux_key_permission,
5758 .key_getsecurity = selinux_key_getsecurity,
5759 #endif
5760
5761 #ifdef CONFIG_AUDIT
5762 .audit_rule_init = selinux_audit_rule_init,
5763 .audit_rule_known = selinux_audit_rule_known,
5764 .audit_rule_match = selinux_audit_rule_match,
5765 .audit_rule_free = selinux_audit_rule_free,
5766 #endif
5767 };
5768
5769 static __init int selinux_init(void)
5770 {
5771 if (!security_module_enable(&selinux_ops)) {
5772 selinux_enabled = 0;
5773 return 0;
5774 }
5775
5776 if (!selinux_enabled) {
5777 printk(KERN_INFO "SELinux: Disabled at boot.\n");
5778 return 0;
5779 }
5780
5781 printk(KERN_INFO "SELinux: Initializing.\n");
5782
5783 /* Set the security state for the initial task. */
5784 cred_init_security();
5785
5786 default_noexec = !(VM_DATA_DEFAULT_FLAGS & VM_EXEC);
5787
5788 sel_inode_cache = kmem_cache_create("selinux_inode_security",
5789 sizeof(struct inode_security_struct),
5790 0, SLAB_PANIC, NULL);
5791 avc_init();
5792
5793 if (register_security(&selinux_ops))
5794 panic("SELinux: Unable to register with kernel.\n");
5795
5796 if (selinux_enforcing)
5797 printk(KERN_DEBUG "SELinux: Starting in enforcing mode\n");
5798 else
5799 printk(KERN_DEBUG "SELinux: Starting in permissive mode\n");
5800
5801 return 0;
5802 }
5803
5804 static void delayed_superblock_init(struct super_block *sb, void *unused)
5805 {
5806 superblock_doinit(sb, NULL);
5807 }
5808
5809 void selinux_complete_init(void)
5810 {
5811 printk(KERN_DEBUG "SELinux: Completing initialization.\n");
5812
5813 /* Set up any superblocks initialized prior to the policy load. */
5814 printk(KERN_DEBUG "SELinux: Setting up existing superblocks.\n");
5815 iterate_supers(delayed_superblock_init, NULL);
5816 }
5817
5818 /* SELinux requires early initialization in order to label
5819 all processes and objects when they are created. */
5820 security_initcall(selinux_init);
5821
5822 #if defined(CONFIG_NETFILTER)
5823
5824 static struct nf_hook_ops selinux_ipv4_ops[] = {
5825 {
5826 .hook = selinux_ipv4_postroute,
5827 .owner = THIS_MODULE,
5828 .pf = NFPROTO_IPV4,
5829 .hooknum = NF_INET_POST_ROUTING,
5830 .priority = NF_IP_PRI_SELINUX_LAST,
5831 },
5832 {
5833 .hook = selinux_ipv4_forward,
5834 .owner = THIS_MODULE,
5835 .pf = NFPROTO_IPV4,
5836 .hooknum = NF_INET_FORWARD,
5837 .priority = NF_IP_PRI_SELINUX_FIRST,
5838 },
5839 {
5840 .hook = selinux_ipv4_output,
5841 .owner = THIS_MODULE,
5842 .pf = NFPROTO_IPV4,
5843 .hooknum = NF_INET_LOCAL_OUT,
5844 .priority = NF_IP_PRI_SELINUX_FIRST,
5845 }
5846 };
5847
5848 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
5849
5850 static struct nf_hook_ops selinux_ipv6_ops[] = {
5851 {
5852 .hook = selinux_ipv6_postroute,
5853 .owner = THIS_MODULE,
5854 .pf = NFPROTO_IPV6,
5855 .hooknum = NF_INET_POST_ROUTING,
5856 .priority = NF_IP6_PRI_SELINUX_LAST,
5857 },
5858 {
5859 .hook = selinux_ipv6_forward,
5860 .owner = THIS_MODULE,
5861 .pf = NFPROTO_IPV6,
5862 .hooknum = NF_INET_FORWARD,
5863 .priority = NF_IP6_PRI_SELINUX_FIRST,
5864 }
5865 };
5866
5867 #endif /* IPV6 */
5868
5869 static int __init selinux_nf_ip_init(void)
5870 {
5871 int err = 0;
5872
5873 if (!selinux_enabled)
5874 goto out;
5875
5876 printk(KERN_DEBUG "SELinux: Registering netfilter hooks\n");
5877
5878 err = nf_register_hooks(selinux_ipv4_ops, ARRAY_SIZE(selinux_ipv4_ops));
5879 if (err)
5880 panic("SELinux: nf_register_hooks for IPv4: error %d\n", err);
5881
5882 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
5883 err = nf_register_hooks(selinux_ipv6_ops, ARRAY_SIZE(selinux_ipv6_ops));
5884 if (err)
5885 panic("SELinux: nf_register_hooks for IPv6: error %d\n", err);
5886 #endif /* IPV6 */
5887
5888 out:
5889 return err;
5890 }
5891
5892 __initcall(selinux_nf_ip_init);
5893
5894 #ifdef CONFIG_SECURITY_SELINUX_DISABLE
5895 static void selinux_nf_ip_exit(void)
5896 {
5897 printk(KERN_DEBUG "SELinux: Unregistering netfilter hooks\n");
5898
5899 nf_unregister_hooks(selinux_ipv4_ops, ARRAY_SIZE(selinux_ipv4_ops));
5900 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
5901 nf_unregister_hooks(selinux_ipv6_ops, ARRAY_SIZE(selinux_ipv6_ops));
5902 #endif /* IPV6 */
5903 }
5904 #endif
5905
5906 #else /* CONFIG_NETFILTER */
5907
5908 #ifdef CONFIG_SECURITY_SELINUX_DISABLE
5909 #define selinux_nf_ip_exit()
5910 #endif
5911
5912 #endif /* CONFIG_NETFILTER */
5913
5914 #ifdef CONFIG_SECURITY_SELINUX_DISABLE
5915 static int selinux_disabled;
5916
5917 int selinux_disable(void)
5918 {
5919 if (ss_initialized) {
5920 /* Not permitted after initial policy load. */
5921 return -EINVAL;
5922 }
5923
5924 if (selinux_disabled) {
5925 /* Only do this once. */
5926 return -EINVAL;
5927 }
5928
5929 printk(KERN_INFO "SELinux: Disabled at runtime.\n");
5930
5931 selinux_disabled = 1;
5932 selinux_enabled = 0;
5933
5934 reset_security_ops();
5935
5936 /* Try to destroy the avc node cache */
5937 avc_disable();
5938
5939 /* Unregister netfilter hooks. */
5940 selinux_nf_ip_exit();
5941
5942 /* Unregister selinuxfs. */
5943 exit_sel_fs();
5944
5945 return 0;
5946 }
5947 #endif
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