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vfs: kill FS_REVAL_DOT by adding a d_weak_revalidate dentry op
[deliverable/linux.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/tcp.h> /* struct or_callable used in sock_rcv_skb */
55 #include <net/net_namespace.h>
56 #include <net/netlabel.h>
57 #include <linux/uaccess.h>
58 #include <asm/ioctls.h>
59 #include <linux/atomic.h>
60 #include <linux/bitops.h>
61 #include <linux/interrupt.h>
62 #include <linux/netdevice.h> /* for network interface checks */
63 #include <linux/netlink.h>
64 #include <linux/tcp.h>
65 #include <linux/udp.h>
66 #include <linux/dccp.h>
67 #include <linux/quota.h>
68 #include <linux/un.h> /* for Unix socket types */
69 #include <net/af_unix.h> /* for Unix socket types */
70 #include <linux/parser.h>
71 #include <linux/nfs_mount.h>
72 #include <net/ipv6.h>
73 #include <linux/hugetlb.h>
74 #include <linux/personality.h>
75 #include <linux/audit.h>
76 #include <linux/string.h>
77 #include <linux/selinux.h>
78 #include <linux/mutex.h>
79 #include <linux/posix-timers.h>
80 #include <linux/syslog.h>
81 #include <linux/user_namespace.h>
82 #include <linux/export.h>
83 #include <linux/msg.h>
84 #include <linux/shm.h>
85
86 #include "avc.h"
87 #include "objsec.h"
88 #include "netif.h"
89 #include "netnode.h"
90 #include "netport.h"
91 #include "xfrm.h"
92 #include "netlabel.h"
93 #include "audit.h"
94 #include "avc_ss.h"
95
96 #define NUM_SEL_MNT_OPTS 5
97
98 extern struct security_operations *security_ops;
99
100 /* SECMARK reference count */
101 static atomic_t selinux_secmark_refcount = ATOMIC_INIT(0);
102
103 #ifdef CONFIG_SECURITY_SELINUX_DEVELOP
104 int selinux_enforcing;
105
106 static int __init enforcing_setup(char *str)
107 {
108 unsigned long enforcing;
109 if (!strict_strtoul(str, 0, &enforcing))
110 selinux_enforcing = enforcing ? 1 : 0;
111 return 1;
112 }
113 __setup("enforcing=", enforcing_setup);
114 #endif
115
116 #ifdef CONFIG_SECURITY_SELINUX_BOOTPARAM
117 int selinux_enabled = CONFIG_SECURITY_SELINUX_BOOTPARAM_VALUE;
118
119 static int __init selinux_enabled_setup(char *str)
120 {
121 unsigned long enabled;
122 if (!strict_strtoul(str, 0, &enabled))
123 selinux_enabled = enabled ? 1 : 0;
124 return 1;
125 }
126 __setup("selinux=", selinux_enabled_setup);
127 #else
128 int selinux_enabled = 1;
129 #endif
130
131 static struct kmem_cache *sel_inode_cache;
132
133 /**
134 * selinux_secmark_enabled - Check to see if SECMARK is currently enabled
135 *
136 * Description:
137 * This function checks the SECMARK reference counter to see if any SECMARK
138 * targets are currently configured, if the reference counter is greater than
139 * zero SECMARK is considered to be enabled. Returns true (1) if SECMARK is
140 * enabled, false (0) if SECMARK is disabled.
141 *
142 */
143 static int selinux_secmark_enabled(void)
144 {
145 return (atomic_read(&selinux_secmark_refcount) > 0);
146 }
147
148 /*
149 * initialise the security for the init task
150 */
151 static void cred_init_security(void)
152 {
153 struct cred *cred = (struct cred *) current->real_cred;
154 struct task_security_struct *tsec;
155
156 tsec = kzalloc(sizeof(struct task_security_struct), GFP_KERNEL);
157 if (!tsec)
158 panic("SELinux: Failed to initialize initial task.\n");
159
160 tsec->osid = tsec->sid = SECINITSID_KERNEL;
161 cred->security = tsec;
162 }
163
164 /*
165 * get the security ID of a set of credentials
166 */
167 static inline u32 cred_sid(const struct cred *cred)
168 {
169 const struct task_security_struct *tsec;
170
171 tsec = cred->security;
172 return tsec->sid;
173 }
174
175 /*
176 * get the objective security ID of a task
177 */
178 static inline u32 task_sid(const struct task_struct *task)
179 {
180 u32 sid;
181
182 rcu_read_lock();
183 sid = cred_sid(__task_cred(task));
184 rcu_read_unlock();
185 return sid;
186 }
187
188 /*
189 * get the subjective security ID of the current task
190 */
191 static inline u32 current_sid(void)
192 {
193 const struct task_security_struct *tsec = current_security();
194
195 return tsec->sid;
196 }
197
198 /* Allocate and free functions for each kind of security blob. */
199
200 static int inode_alloc_security(struct inode *inode)
201 {
202 struct inode_security_struct *isec;
203 u32 sid = current_sid();
204
205 isec = kmem_cache_zalloc(sel_inode_cache, GFP_NOFS);
206 if (!isec)
207 return -ENOMEM;
208
209 mutex_init(&isec->lock);
210 INIT_LIST_HEAD(&isec->list);
211 isec->inode = inode;
212 isec->sid = SECINITSID_UNLABELED;
213 isec->sclass = SECCLASS_FILE;
214 isec->task_sid = sid;
215 inode->i_security = isec;
216
217 return 0;
218 }
219
220 static void inode_free_security(struct inode *inode)
221 {
222 struct inode_security_struct *isec = inode->i_security;
223 struct superblock_security_struct *sbsec = inode->i_sb->s_security;
224
225 spin_lock(&sbsec->isec_lock);
226 if (!list_empty(&isec->list))
227 list_del_init(&isec->list);
228 spin_unlock(&sbsec->isec_lock);
229
230 inode->i_security = NULL;
231 kmem_cache_free(sel_inode_cache, isec);
232 }
233
234 static int file_alloc_security(struct file *file)
235 {
236 struct file_security_struct *fsec;
237 u32 sid = current_sid();
238
239 fsec = kzalloc(sizeof(struct file_security_struct), GFP_KERNEL);
240 if (!fsec)
241 return -ENOMEM;
242
243 fsec->sid = sid;
244 fsec->fown_sid = sid;
245 file->f_security = fsec;
246
247 return 0;
248 }
249
250 static void file_free_security(struct file *file)
251 {
252 struct file_security_struct *fsec = file->f_security;
253 file->f_security = NULL;
254 kfree(fsec);
255 }
256
257 static int superblock_alloc_security(struct super_block *sb)
258 {
259 struct superblock_security_struct *sbsec;
260
261 sbsec = kzalloc(sizeof(struct superblock_security_struct), GFP_KERNEL);
262 if (!sbsec)
263 return -ENOMEM;
264
265 mutex_init(&sbsec->lock);
266 INIT_LIST_HEAD(&sbsec->isec_head);
267 spin_lock_init(&sbsec->isec_lock);
268 sbsec->sb = sb;
269 sbsec->sid = SECINITSID_UNLABELED;
270 sbsec->def_sid = SECINITSID_FILE;
271 sbsec->mntpoint_sid = SECINITSID_UNLABELED;
272 sb->s_security = sbsec;
273
274 return 0;
275 }
276
277 static void superblock_free_security(struct super_block *sb)
278 {
279 struct superblock_security_struct *sbsec = sb->s_security;
280 sb->s_security = NULL;
281 kfree(sbsec);
282 }
283
284 /* The file system's label must be initialized prior to use. */
285
286 static const char *labeling_behaviors[6] = {
287 "uses xattr",
288 "uses transition SIDs",
289 "uses task SIDs",
290 "uses genfs_contexts",
291 "not configured for labeling",
292 "uses mountpoint labeling",
293 };
294
295 static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dentry);
296
297 static inline int inode_doinit(struct inode *inode)
298 {
299 return inode_doinit_with_dentry(inode, NULL);
300 }
301
302 enum {
303 Opt_error = -1,
304 Opt_context = 1,
305 Opt_fscontext = 2,
306 Opt_defcontext = 3,
307 Opt_rootcontext = 4,
308 Opt_labelsupport = 5,
309 };
310
311 static const match_table_t tokens = {
312 {Opt_context, CONTEXT_STR "%s"},
313 {Opt_fscontext, FSCONTEXT_STR "%s"},
314 {Opt_defcontext, DEFCONTEXT_STR "%s"},
315 {Opt_rootcontext, ROOTCONTEXT_STR "%s"},
316 {Opt_labelsupport, LABELSUPP_STR},
317 {Opt_error, NULL},
318 };
319
320 #define SEL_MOUNT_FAIL_MSG "SELinux: duplicate or incompatible mount options\n"
321
322 static int may_context_mount_sb_relabel(u32 sid,
323 struct superblock_security_struct *sbsec,
324 const struct cred *cred)
325 {
326 const struct task_security_struct *tsec = cred->security;
327 int rc;
328
329 rc = avc_has_perm(tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM,
330 FILESYSTEM__RELABELFROM, NULL);
331 if (rc)
332 return rc;
333
334 rc = avc_has_perm(tsec->sid, sid, SECCLASS_FILESYSTEM,
335 FILESYSTEM__RELABELTO, NULL);
336 return rc;
337 }
338
339 static int may_context_mount_inode_relabel(u32 sid,
340 struct superblock_security_struct *sbsec,
341 const struct cred *cred)
342 {
343 const struct task_security_struct *tsec = cred->security;
344 int rc;
345 rc = avc_has_perm(tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM,
346 FILESYSTEM__RELABELFROM, NULL);
347 if (rc)
348 return rc;
349
350 rc = avc_has_perm(sid, sbsec->sid, SECCLASS_FILESYSTEM,
351 FILESYSTEM__ASSOCIATE, NULL);
352 return rc;
353 }
354
355 static int sb_finish_set_opts(struct super_block *sb)
356 {
357 struct superblock_security_struct *sbsec = sb->s_security;
358 struct dentry *root = sb->s_root;
359 struct inode *root_inode = root->d_inode;
360 int rc = 0;
361
362 if (sbsec->behavior == SECURITY_FS_USE_XATTR) {
363 /* Make sure that the xattr handler exists and that no
364 error other than -ENODATA is returned by getxattr on
365 the root directory. -ENODATA is ok, as this may be
366 the first boot of the SELinux kernel before we have
367 assigned xattr values to the filesystem. */
368 if (!root_inode->i_op->getxattr) {
369 printk(KERN_WARNING "SELinux: (dev %s, type %s) has no "
370 "xattr support\n", sb->s_id, sb->s_type->name);
371 rc = -EOPNOTSUPP;
372 goto out;
373 }
374 rc = root_inode->i_op->getxattr(root, XATTR_NAME_SELINUX, NULL, 0);
375 if (rc < 0 && rc != -ENODATA) {
376 if (rc == -EOPNOTSUPP)
377 printk(KERN_WARNING "SELinux: (dev %s, type "
378 "%s) has no security xattr handler\n",
379 sb->s_id, sb->s_type->name);
380 else
381 printk(KERN_WARNING "SELinux: (dev %s, type "
382 "%s) getxattr errno %d\n", sb->s_id,
383 sb->s_type->name, -rc);
384 goto out;
385 }
386 }
387
388 sbsec->flags |= (SE_SBINITIALIZED | SE_SBLABELSUPP);
389
390 if (sbsec->behavior > ARRAY_SIZE(labeling_behaviors))
391 printk(KERN_ERR "SELinux: initialized (dev %s, type %s), unknown behavior\n",
392 sb->s_id, sb->s_type->name);
393 else
394 printk(KERN_DEBUG "SELinux: initialized (dev %s, type %s), %s\n",
395 sb->s_id, sb->s_type->name,
396 labeling_behaviors[sbsec->behavior-1]);
397
398 if (sbsec->behavior == SECURITY_FS_USE_GENFS ||
399 sbsec->behavior == SECURITY_FS_USE_MNTPOINT ||
400 sbsec->behavior == SECURITY_FS_USE_NONE ||
401 sbsec->behavior > ARRAY_SIZE(labeling_behaviors))
402 sbsec->flags &= ~SE_SBLABELSUPP;
403
404 /* Special handling for sysfs. Is genfs but also has setxattr handler*/
405 if (strncmp(sb->s_type->name, "sysfs", sizeof("sysfs")) == 0)
406 sbsec->flags |= SE_SBLABELSUPP;
407
408 /* Initialize the root inode. */
409 rc = inode_doinit_with_dentry(root_inode, root);
410
411 /* Initialize any other inodes associated with the superblock, e.g.
412 inodes created prior to initial policy load or inodes created
413 during get_sb by a pseudo filesystem that directly
414 populates itself. */
415 spin_lock(&sbsec->isec_lock);
416 next_inode:
417 if (!list_empty(&sbsec->isec_head)) {
418 struct inode_security_struct *isec =
419 list_entry(sbsec->isec_head.next,
420 struct inode_security_struct, list);
421 struct inode *inode = isec->inode;
422 spin_unlock(&sbsec->isec_lock);
423 inode = igrab(inode);
424 if (inode) {
425 if (!IS_PRIVATE(inode))
426 inode_doinit(inode);
427 iput(inode);
428 }
429 spin_lock(&sbsec->isec_lock);
430 list_del_init(&isec->list);
431 goto next_inode;
432 }
433 spin_unlock(&sbsec->isec_lock);
434 out:
435 return rc;
436 }
437
438 /*
439 * This function should allow an FS to ask what it's mount security
440 * options were so it can use those later for submounts, displaying
441 * mount options, or whatever.
442 */
443 static int selinux_get_mnt_opts(const struct super_block *sb,
444 struct security_mnt_opts *opts)
445 {
446 int rc = 0, i;
447 struct superblock_security_struct *sbsec = sb->s_security;
448 char *context = NULL;
449 u32 len;
450 char tmp;
451
452 security_init_mnt_opts(opts);
453
454 if (!(sbsec->flags & SE_SBINITIALIZED))
455 return -EINVAL;
456
457 if (!ss_initialized)
458 return -EINVAL;
459
460 tmp = sbsec->flags & SE_MNTMASK;
461 /* count the number of mount options for this sb */
462 for (i = 0; i < 8; i++) {
463 if (tmp & 0x01)
464 opts->num_mnt_opts++;
465 tmp >>= 1;
466 }
467 /* Check if the Label support flag is set */
468 if (sbsec->flags & SE_SBLABELSUPP)
469 opts->num_mnt_opts++;
470
471 opts->mnt_opts = kcalloc(opts->num_mnt_opts, sizeof(char *), GFP_ATOMIC);
472 if (!opts->mnt_opts) {
473 rc = -ENOMEM;
474 goto out_free;
475 }
476
477 opts->mnt_opts_flags = kcalloc(opts->num_mnt_opts, sizeof(int), GFP_ATOMIC);
478 if (!opts->mnt_opts_flags) {
479 rc = -ENOMEM;
480 goto out_free;
481 }
482
483 i = 0;
484 if (sbsec->flags & FSCONTEXT_MNT) {
485 rc = security_sid_to_context(sbsec->sid, &context, &len);
486 if (rc)
487 goto out_free;
488 opts->mnt_opts[i] = context;
489 opts->mnt_opts_flags[i++] = FSCONTEXT_MNT;
490 }
491 if (sbsec->flags & CONTEXT_MNT) {
492 rc = security_sid_to_context(sbsec->mntpoint_sid, &context, &len);
493 if (rc)
494 goto out_free;
495 opts->mnt_opts[i] = context;
496 opts->mnt_opts_flags[i++] = CONTEXT_MNT;
497 }
498 if (sbsec->flags & DEFCONTEXT_MNT) {
499 rc = security_sid_to_context(sbsec->def_sid, &context, &len);
500 if (rc)
501 goto out_free;
502 opts->mnt_opts[i] = context;
503 opts->mnt_opts_flags[i++] = DEFCONTEXT_MNT;
504 }
505 if (sbsec->flags & ROOTCONTEXT_MNT) {
506 struct inode *root = sbsec->sb->s_root->d_inode;
507 struct inode_security_struct *isec = root->i_security;
508
509 rc = security_sid_to_context(isec->sid, &context, &len);
510 if (rc)
511 goto out_free;
512 opts->mnt_opts[i] = context;
513 opts->mnt_opts_flags[i++] = ROOTCONTEXT_MNT;
514 }
515 if (sbsec->flags & SE_SBLABELSUPP) {
516 opts->mnt_opts[i] = NULL;
517 opts->mnt_opts_flags[i++] = SE_SBLABELSUPP;
518 }
519
520 BUG_ON(i != opts->num_mnt_opts);
521
522 return 0;
523
524 out_free:
525 security_free_mnt_opts(opts);
526 return rc;
527 }
528
529 static int bad_option(struct superblock_security_struct *sbsec, char flag,
530 u32 old_sid, u32 new_sid)
531 {
532 char mnt_flags = sbsec->flags & SE_MNTMASK;
533
534 /* check if the old mount command had the same options */
535 if (sbsec->flags & SE_SBINITIALIZED)
536 if (!(sbsec->flags & flag) ||
537 (old_sid != new_sid))
538 return 1;
539
540 /* check if we were passed the same options twice,
541 * aka someone passed context=a,context=b
542 */
543 if (!(sbsec->flags & SE_SBINITIALIZED))
544 if (mnt_flags & flag)
545 return 1;
546 return 0;
547 }
548
549 /*
550 * Allow filesystems with binary mount data to explicitly set mount point
551 * labeling information.
552 */
553 static int selinux_set_mnt_opts(struct super_block *sb,
554 struct security_mnt_opts *opts)
555 {
556 const struct cred *cred = current_cred();
557 int rc = 0, i;
558 struct superblock_security_struct *sbsec = sb->s_security;
559 const char *name = sb->s_type->name;
560 struct inode *inode = sbsec->sb->s_root->d_inode;
561 struct inode_security_struct *root_isec = inode->i_security;
562 u32 fscontext_sid = 0, context_sid = 0, rootcontext_sid = 0;
563 u32 defcontext_sid = 0;
564 char **mount_options = opts->mnt_opts;
565 int *flags = opts->mnt_opts_flags;
566 int num_opts = opts->num_mnt_opts;
567
568 mutex_lock(&sbsec->lock);
569
570 if (!ss_initialized) {
571 if (!num_opts) {
572 /* Defer initialization until selinux_complete_init,
573 after the initial policy is loaded and the security
574 server is ready to handle calls. */
575 goto out;
576 }
577 rc = -EINVAL;
578 printk(KERN_WARNING "SELinux: Unable to set superblock options "
579 "before the security server is initialized\n");
580 goto out;
581 }
582
583 /*
584 * Binary mount data FS will come through this function twice. Once
585 * from an explicit call and once from the generic calls from the vfs.
586 * Since the generic VFS calls will not contain any security mount data
587 * we need to skip the double mount verification.
588 *
589 * This does open a hole in which we will not notice if the first
590 * mount using this sb set explict options and a second mount using
591 * this sb does not set any security options. (The first options
592 * will be used for both mounts)
593 */
594 if ((sbsec->flags & SE_SBINITIALIZED) && (sb->s_type->fs_flags & FS_BINARY_MOUNTDATA)
595 && (num_opts == 0))
596 goto out;
597
598 /*
599 * parse the mount options, check if they are valid sids.
600 * also check if someone is trying to mount the same sb more
601 * than once with different security options.
602 */
603 for (i = 0; i < num_opts; i++) {
604 u32 sid;
605
606 if (flags[i] == SE_SBLABELSUPP)
607 continue;
608 rc = security_context_to_sid(mount_options[i],
609 strlen(mount_options[i]), &sid);
610 if (rc) {
611 printk(KERN_WARNING "SELinux: security_context_to_sid"
612 "(%s) failed for (dev %s, type %s) errno=%d\n",
613 mount_options[i], sb->s_id, name, rc);
614 goto out;
615 }
616 switch (flags[i]) {
617 case FSCONTEXT_MNT:
618 fscontext_sid = sid;
619
620 if (bad_option(sbsec, FSCONTEXT_MNT, sbsec->sid,
621 fscontext_sid))
622 goto out_double_mount;
623
624 sbsec->flags |= FSCONTEXT_MNT;
625 break;
626 case CONTEXT_MNT:
627 context_sid = sid;
628
629 if (bad_option(sbsec, CONTEXT_MNT, sbsec->mntpoint_sid,
630 context_sid))
631 goto out_double_mount;
632
633 sbsec->flags |= CONTEXT_MNT;
634 break;
635 case ROOTCONTEXT_MNT:
636 rootcontext_sid = sid;
637
638 if (bad_option(sbsec, ROOTCONTEXT_MNT, root_isec->sid,
639 rootcontext_sid))
640 goto out_double_mount;
641
642 sbsec->flags |= ROOTCONTEXT_MNT;
643
644 break;
645 case DEFCONTEXT_MNT:
646 defcontext_sid = sid;
647
648 if (bad_option(sbsec, DEFCONTEXT_MNT, sbsec->def_sid,
649 defcontext_sid))
650 goto out_double_mount;
651
652 sbsec->flags |= DEFCONTEXT_MNT;
653
654 break;
655 default:
656 rc = -EINVAL;
657 goto out;
658 }
659 }
660
661 if (sbsec->flags & SE_SBINITIALIZED) {
662 /* previously mounted with options, but not on this attempt? */
663 if ((sbsec->flags & SE_MNTMASK) && !num_opts)
664 goto out_double_mount;
665 rc = 0;
666 goto out;
667 }
668
669 if (strcmp(sb->s_type->name, "proc") == 0)
670 sbsec->flags |= SE_SBPROC;
671
672 /* Determine the labeling behavior to use for this filesystem type. */
673 rc = security_fs_use((sbsec->flags & SE_SBPROC) ? "proc" : sb->s_type->name, &sbsec->behavior, &sbsec->sid);
674 if (rc) {
675 printk(KERN_WARNING "%s: security_fs_use(%s) returned %d\n",
676 __func__, sb->s_type->name, rc);
677 goto out;
678 }
679
680 /* sets the context of the superblock for the fs being mounted. */
681 if (fscontext_sid) {
682 rc = may_context_mount_sb_relabel(fscontext_sid, sbsec, cred);
683 if (rc)
684 goto out;
685
686 sbsec->sid = fscontext_sid;
687 }
688
689 /*
690 * Switch to using mount point labeling behavior.
691 * sets the label used on all file below the mountpoint, and will set
692 * the superblock context if not already set.
693 */
694 if (context_sid) {
695 if (!fscontext_sid) {
696 rc = may_context_mount_sb_relabel(context_sid, sbsec,
697 cred);
698 if (rc)
699 goto out;
700 sbsec->sid = context_sid;
701 } else {
702 rc = may_context_mount_inode_relabel(context_sid, sbsec,
703 cred);
704 if (rc)
705 goto out;
706 }
707 if (!rootcontext_sid)
708 rootcontext_sid = context_sid;
709
710 sbsec->mntpoint_sid = context_sid;
711 sbsec->behavior = SECURITY_FS_USE_MNTPOINT;
712 }
713
714 if (rootcontext_sid) {
715 rc = may_context_mount_inode_relabel(rootcontext_sid, sbsec,
716 cred);
717 if (rc)
718 goto out;
719
720 root_isec->sid = rootcontext_sid;
721 root_isec->initialized = 1;
722 }
723
724 if (defcontext_sid) {
725 if (sbsec->behavior != SECURITY_FS_USE_XATTR) {
726 rc = -EINVAL;
727 printk(KERN_WARNING "SELinux: defcontext option is "
728 "invalid for this filesystem type\n");
729 goto out;
730 }
731
732 if (defcontext_sid != sbsec->def_sid) {
733 rc = may_context_mount_inode_relabel(defcontext_sid,
734 sbsec, cred);
735 if (rc)
736 goto out;
737 }
738
739 sbsec->def_sid = defcontext_sid;
740 }
741
742 rc = sb_finish_set_opts(sb);
743 out:
744 mutex_unlock(&sbsec->lock);
745 return rc;
746 out_double_mount:
747 rc = -EINVAL;
748 printk(KERN_WARNING "SELinux: mount invalid. Same superblock, different "
749 "security settings for (dev %s, type %s)\n", sb->s_id, name);
750 goto out;
751 }
752
753 static void selinux_sb_clone_mnt_opts(const struct super_block *oldsb,
754 struct super_block *newsb)
755 {
756 const struct superblock_security_struct *oldsbsec = oldsb->s_security;
757 struct superblock_security_struct *newsbsec = newsb->s_security;
758
759 int set_fscontext = (oldsbsec->flags & FSCONTEXT_MNT);
760 int set_context = (oldsbsec->flags & CONTEXT_MNT);
761 int set_rootcontext = (oldsbsec->flags & ROOTCONTEXT_MNT);
762
763 /*
764 * if the parent was able to be mounted it clearly had no special lsm
765 * mount options. thus we can safely deal with this superblock later
766 */
767 if (!ss_initialized)
768 return;
769
770 /* how can we clone if the old one wasn't set up?? */
771 BUG_ON(!(oldsbsec->flags & SE_SBINITIALIZED));
772
773 /* if fs is reusing a sb, just let its options stand... */
774 if (newsbsec->flags & SE_SBINITIALIZED)
775 return;
776
777 mutex_lock(&newsbsec->lock);
778
779 newsbsec->flags = oldsbsec->flags;
780
781 newsbsec->sid = oldsbsec->sid;
782 newsbsec->def_sid = oldsbsec->def_sid;
783 newsbsec->behavior = oldsbsec->behavior;
784
785 if (set_context) {
786 u32 sid = oldsbsec->mntpoint_sid;
787
788 if (!set_fscontext)
789 newsbsec->sid = sid;
790 if (!set_rootcontext) {
791 struct inode *newinode = newsb->s_root->d_inode;
792 struct inode_security_struct *newisec = newinode->i_security;
793 newisec->sid = sid;
794 }
795 newsbsec->mntpoint_sid = sid;
796 }
797 if (set_rootcontext) {
798 const struct inode *oldinode = oldsb->s_root->d_inode;
799 const struct inode_security_struct *oldisec = oldinode->i_security;
800 struct inode *newinode = newsb->s_root->d_inode;
801 struct inode_security_struct *newisec = newinode->i_security;
802
803 newisec->sid = oldisec->sid;
804 }
805
806 sb_finish_set_opts(newsb);
807 mutex_unlock(&newsbsec->lock);
808 }
809
810 static int selinux_parse_opts_str(char *options,
811 struct security_mnt_opts *opts)
812 {
813 char *p;
814 char *context = NULL, *defcontext = NULL;
815 char *fscontext = NULL, *rootcontext = NULL;
816 int rc, num_mnt_opts = 0;
817
818 opts->num_mnt_opts = 0;
819
820 /* Standard string-based options. */
821 while ((p = strsep(&options, "|")) != NULL) {
822 int token;
823 substring_t args[MAX_OPT_ARGS];
824
825 if (!*p)
826 continue;
827
828 token = match_token(p, tokens, args);
829
830 switch (token) {
831 case Opt_context:
832 if (context || defcontext) {
833 rc = -EINVAL;
834 printk(KERN_WARNING SEL_MOUNT_FAIL_MSG);
835 goto out_err;
836 }
837 context = match_strdup(&args[0]);
838 if (!context) {
839 rc = -ENOMEM;
840 goto out_err;
841 }
842 break;
843
844 case Opt_fscontext:
845 if (fscontext) {
846 rc = -EINVAL;
847 printk(KERN_WARNING SEL_MOUNT_FAIL_MSG);
848 goto out_err;
849 }
850 fscontext = match_strdup(&args[0]);
851 if (!fscontext) {
852 rc = -ENOMEM;
853 goto out_err;
854 }
855 break;
856
857 case Opt_rootcontext:
858 if (rootcontext) {
859 rc = -EINVAL;
860 printk(KERN_WARNING SEL_MOUNT_FAIL_MSG);
861 goto out_err;
862 }
863 rootcontext = match_strdup(&args[0]);
864 if (!rootcontext) {
865 rc = -ENOMEM;
866 goto out_err;
867 }
868 break;
869
870 case Opt_defcontext:
871 if (context || defcontext) {
872 rc = -EINVAL;
873 printk(KERN_WARNING SEL_MOUNT_FAIL_MSG);
874 goto out_err;
875 }
876 defcontext = match_strdup(&args[0]);
877 if (!defcontext) {
878 rc = -ENOMEM;
879 goto out_err;
880 }
881 break;
882 case Opt_labelsupport:
883 break;
884 default:
885 rc = -EINVAL;
886 printk(KERN_WARNING "SELinux: unknown mount option\n");
887 goto out_err;
888
889 }
890 }
891
892 rc = -ENOMEM;
893 opts->mnt_opts = kcalloc(NUM_SEL_MNT_OPTS, sizeof(char *), GFP_ATOMIC);
894 if (!opts->mnt_opts)
895 goto out_err;
896
897 opts->mnt_opts_flags = kcalloc(NUM_SEL_MNT_OPTS, sizeof(int), GFP_ATOMIC);
898 if (!opts->mnt_opts_flags) {
899 kfree(opts->mnt_opts);
900 goto out_err;
901 }
902
903 if (fscontext) {
904 opts->mnt_opts[num_mnt_opts] = fscontext;
905 opts->mnt_opts_flags[num_mnt_opts++] = FSCONTEXT_MNT;
906 }
907 if (context) {
908 opts->mnt_opts[num_mnt_opts] = context;
909 opts->mnt_opts_flags[num_mnt_opts++] = CONTEXT_MNT;
910 }
911 if (rootcontext) {
912 opts->mnt_opts[num_mnt_opts] = rootcontext;
913 opts->mnt_opts_flags[num_mnt_opts++] = ROOTCONTEXT_MNT;
914 }
915 if (defcontext) {
916 opts->mnt_opts[num_mnt_opts] = defcontext;
917 opts->mnt_opts_flags[num_mnt_opts++] = DEFCONTEXT_MNT;
918 }
919
920 opts->num_mnt_opts = num_mnt_opts;
921 return 0;
922
923 out_err:
924 kfree(context);
925 kfree(defcontext);
926 kfree(fscontext);
927 kfree(rootcontext);
928 return rc;
929 }
930 /*
931 * string mount options parsing and call set the sbsec
932 */
933 static int superblock_doinit(struct super_block *sb, void *data)
934 {
935 int rc = 0;
936 char *options = data;
937 struct security_mnt_opts opts;
938
939 security_init_mnt_opts(&opts);
940
941 if (!data)
942 goto out;
943
944 BUG_ON(sb->s_type->fs_flags & FS_BINARY_MOUNTDATA);
945
946 rc = selinux_parse_opts_str(options, &opts);
947 if (rc)
948 goto out_err;
949
950 out:
951 rc = selinux_set_mnt_opts(sb, &opts);
952
953 out_err:
954 security_free_mnt_opts(&opts);
955 return rc;
956 }
957
958 static void selinux_write_opts(struct seq_file *m,
959 struct security_mnt_opts *opts)
960 {
961 int i;
962 char *prefix;
963
964 for (i = 0; i < opts->num_mnt_opts; i++) {
965 char *has_comma;
966
967 if (opts->mnt_opts[i])
968 has_comma = strchr(opts->mnt_opts[i], ',');
969 else
970 has_comma = NULL;
971
972 switch (opts->mnt_opts_flags[i]) {
973 case CONTEXT_MNT:
974 prefix = CONTEXT_STR;
975 break;
976 case FSCONTEXT_MNT:
977 prefix = FSCONTEXT_STR;
978 break;
979 case ROOTCONTEXT_MNT:
980 prefix = ROOTCONTEXT_STR;
981 break;
982 case DEFCONTEXT_MNT:
983 prefix = DEFCONTEXT_STR;
984 break;
985 case SE_SBLABELSUPP:
986 seq_putc(m, ',');
987 seq_puts(m, LABELSUPP_STR);
988 continue;
989 default:
990 BUG();
991 return;
992 };
993 /* we need a comma before each option */
994 seq_putc(m, ',');
995 seq_puts(m, prefix);
996 if (has_comma)
997 seq_putc(m, '\"');
998 seq_puts(m, opts->mnt_opts[i]);
999 if (has_comma)
1000 seq_putc(m, '\"');
1001 }
1002 }
1003
1004 static int selinux_sb_show_options(struct seq_file *m, struct super_block *sb)
1005 {
1006 struct security_mnt_opts opts;
1007 int rc;
1008
1009 rc = selinux_get_mnt_opts(sb, &opts);
1010 if (rc) {
1011 /* before policy load we may get EINVAL, don't show anything */
1012 if (rc == -EINVAL)
1013 rc = 0;
1014 return rc;
1015 }
1016
1017 selinux_write_opts(m, &opts);
1018
1019 security_free_mnt_opts(&opts);
1020
1021 return rc;
1022 }
1023
1024 static inline u16 inode_mode_to_security_class(umode_t mode)
1025 {
1026 switch (mode & S_IFMT) {
1027 case S_IFSOCK:
1028 return SECCLASS_SOCK_FILE;
1029 case S_IFLNK:
1030 return SECCLASS_LNK_FILE;
1031 case S_IFREG:
1032 return SECCLASS_FILE;
1033 case S_IFBLK:
1034 return SECCLASS_BLK_FILE;
1035 case S_IFDIR:
1036 return SECCLASS_DIR;
1037 case S_IFCHR:
1038 return SECCLASS_CHR_FILE;
1039 case S_IFIFO:
1040 return SECCLASS_FIFO_FILE;
1041
1042 }
1043
1044 return SECCLASS_FILE;
1045 }
1046
1047 static inline int default_protocol_stream(int protocol)
1048 {
1049 return (protocol == IPPROTO_IP || protocol == IPPROTO_TCP);
1050 }
1051
1052 static inline int default_protocol_dgram(int protocol)
1053 {
1054 return (protocol == IPPROTO_IP || protocol == IPPROTO_UDP);
1055 }
1056
1057 static inline u16 socket_type_to_security_class(int family, int type, int protocol)
1058 {
1059 switch (family) {
1060 case PF_UNIX:
1061 switch (type) {
1062 case SOCK_STREAM:
1063 case SOCK_SEQPACKET:
1064 return SECCLASS_UNIX_STREAM_SOCKET;
1065 case SOCK_DGRAM:
1066 return SECCLASS_UNIX_DGRAM_SOCKET;
1067 }
1068 break;
1069 case PF_INET:
1070 case PF_INET6:
1071 switch (type) {
1072 case SOCK_STREAM:
1073 if (default_protocol_stream(protocol))
1074 return SECCLASS_TCP_SOCKET;
1075 else
1076 return SECCLASS_RAWIP_SOCKET;
1077 case SOCK_DGRAM:
1078 if (default_protocol_dgram(protocol))
1079 return SECCLASS_UDP_SOCKET;
1080 else
1081 return SECCLASS_RAWIP_SOCKET;
1082 case SOCK_DCCP:
1083 return SECCLASS_DCCP_SOCKET;
1084 default:
1085 return SECCLASS_RAWIP_SOCKET;
1086 }
1087 break;
1088 case PF_NETLINK:
1089 switch (protocol) {
1090 case NETLINK_ROUTE:
1091 return SECCLASS_NETLINK_ROUTE_SOCKET;
1092 case NETLINK_FIREWALL:
1093 return SECCLASS_NETLINK_FIREWALL_SOCKET;
1094 case NETLINK_SOCK_DIAG:
1095 return SECCLASS_NETLINK_TCPDIAG_SOCKET;
1096 case NETLINK_NFLOG:
1097 return SECCLASS_NETLINK_NFLOG_SOCKET;
1098 case NETLINK_XFRM:
1099 return SECCLASS_NETLINK_XFRM_SOCKET;
1100 case NETLINK_SELINUX:
1101 return SECCLASS_NETLINK_SELINUX_SOCKET;
1102 case NETLINK_AUDIT:
1103 return SECCLASS_NETLINK_AUDIT_SOCKET;
1104 case NETLINK_IP6_FW:
1105 return SECCLASS_NETLINK_IP6FW_SOCKET;
1106 case NETLINK_DNRTMSG:
1107 return SECCLASS_NETLINK_DNRT_SOCKET;
1108 case NETLINK_KOBJECT_UEVENT:
1109 return SECCLASS_NETLINK_KOBJECT_UEVENT_SOCKET;
1110 default:
1111 return SECCLASS_NETLINK_SOCKET;
1112 }
1113 case PF_PACKET:
1114 return SECCLASS_PACKET_SOCKET;
1115 case PF_KEY:
1116 return SECCLASS_KEY_SOCKET;
1117 case PF_APPLETALK:
1118 return SECCLASS_APPLETALK_SOCKET;
1119 }
1120
1121 return SECCLASS_SOCKET;
1122 }
1123
1124 #ifdef CONFIG_PROC_FS
1125 static int selinux_proc_get_sid(struct dentry *dentry,
1126 u16 tclass,
1127 u32 *sid)
1128 {
1129 int rc;
1130 char *buffer, *path;
1131
1132 buffer = (char *)__get_free_page(GFP_KERNEL);
1133 if (!buffer)
1134 return -ENOMEM;
1135
1136 path = dentry_path_raw(dentry, buffer, PAGE_SIZE);
1137 if (IS_ERR(path))
1138 rc = PTR_ERR(path);
1139 else {
1140 /* each process gets a /proc/PID/ entry. Strip off the
1141 * PID part to get a valid selinux labeling.
1142 * e.g. /proc/1/net/rpc/nfs -> /net/rpc/nfs */
1143 while (path[1] >= '0' && path[1] <= '9') {
1144 path[1] = '/';
1145 path++;
1146 }
1147 rc = security_genfs_sid("proc", path, tclass, sid);
1148 }
1149 free_page((unsigned long)buffer);
1150 return rc;
1151 }
1152 #else
1153 static int selinux_proc_get_sid(struct dentry *dentry,
1154 u16 tclass,
1155 u32 *sid)
1156 {
1157 return -EINVAL;
1158 }
1159 #endif
1160
1161 /* The inode's security attributes must be initialized before first use. */
1162 static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dentry)
1163 {
1164 struct superblock_security_struct *sbsec = NULL;
1165 struct inode_security_struct *isec = inode->i_security;
1166 u32 sid;
1167 struct dentry *dentry;
1168 #define INITCONTEXTLEN 255
1169 char *context = NULL;
1170 unsigned len = 0;
1171 int rc = 0;
1172
1173 if (isec->initialized)
1174 goto out;
1175
1176 mutex_lock(&isec->lock);
1177 if (isec->initialized)
1178 goto out_unlock;
1179
1180 sbsec = inode->i_sb->s_security;
1181 if (!(sbsec->flags & SE_SBINITIALIZED)) {
1182 /* Defer initialization until selinux_complete_init,
1183 after the initial policy is loaded and the security
1184 server is ready to handle calls. */
1185 spin_lock(&sbsec->isec_lock);
1186 if (list_empty(&isec->list))
1187 list_add(&isec->list, &sbsec->isec_head);
1188 spin_unlock(&sbsec->isec_lock);
1189 goto out_unlock;
1190 }
1191
1192 switch (sbsec->behavior) {
1193 case SECURITY_FS_USE_XATTR:
1194 if (!inode->i_op->getxattr) {
1195 isec->sid = sbsec->def_sid;
1196 break;
1197 }
1198
1199 /* Need a dentry, since the xattr API requires one.
1200 Life would be simpler if we could just pass the inode. */
1201 if (opt_dentry) {
1202 /* Called from d_instantiate or d_splice_alias. */
1203 dentry = dget(opt_dentry);
1204 } else {
1205 /* Called from selinux_complete_init, try to find a dentry. */
1206 dentry = d_find_alias(inode);
1207 }
1208 if (!dentry) {
1209 /*
1210 * this is can be hit on boot when a file is accessed
1211 * before the policy is loaded. When we load policy we
1212 * may find inodes that have no dentry on the
1213 * sbsec->isec_head list. No reason to complain as these
1214 * will get fixed up the next time we go through
1215 * inode_doinit with a dentry, before these inodes could
1216 * be used again by userspace.
1217 */
1218 goto out_unlock;
1219 }
1220
1221 len = INITCONTEXTLEN;
1222 context = kmalloc(len+1, GFP_NOFS);
1223 if (!context) {
1224 rc = -ENOMEM;
1225 dput(dentry);
1226 goto out_unlock;
1227 }
1228 context[len] = '\0';
1229 rc = inode->i_op->getxattr(dentry, XATTR_NAME_SELINUX,
1230 context, len);
1231 if (rc == -ERANGE) {
1232 kfree(context);
1233
1234 /* Need a larger buffer. Query for the right size. */
1235 rc = inode->i_op->getxattr(dentry, XATTR_NAME_SELINUX,
1236 NULL, 0);
1237 if (rc < 0) {
1238 dput(dentry);
1239 goto out_unlock;
1240 }
1241 len = rc;
1242 context = kmalloc(len+1, GFP_NOFS);
1243 if (!context) {
1244 rc = -ENOMEM;
1245 dput(dentry);
1246 goto out_unlock;
1247 }
1248 context[len] = '\0';
1249 rc = inode->i_op->getxattr(dentry,
1250 XATTR_NAME_SELINUX,
1251 context, len);
1252 }
1253 dput(dentry);
1254 if (rc < 0) {
1255 if (rc != -ENODATA) {
1256 printk(KERN_WARNING "SELinux: %s: getxattr returned "
1257 "%d for dev=%s ino=%ld\n", __func__,
1258 -rc, inode->i_sb->s_id, inode->i_ino);
1259 kfree(context);
1260 goto out_unlock;
1261 }
1262 /* Map ENODATA to the default file SID */
1263 sid = sbsec->def_sid;
1264 rc = 0;
1265 } else {
1266 rc = security_context_to_sid_default(context, rc, &sid,
1267 sbsec->def_sid,
1268 GFP_NOFS);
1269 if (rc) {
1270 char *dev = inode->i_sb->s_id;
1271 unsigned long ino = inode->i_ino;
1272
1273 if (rc == -EINVAL) {
1274 if (printk_ratelimit())
1275 printk(KERN_NOTICE "SELinux: inode=%lu on dev=%s was found to have an invalid "
1276 "context=%s. This indicates you may need to relabel the inode or the "
1277 "filesystem in question.\n", ino, dev, context);
1278 } else {
1279 printk(KERN_WARNING "SELinux: %s: context_to_sid(%s) "
1280 "returned %d for dev=%s ino=%ld\n",
1281 __func__, context, -rc, dev, ino);
1282 }
1283 kfree(context);
1284 /* Leave with the unlabeled SID */
1285 rc = 0;
1286 break;
1287 }
1288 }
1289 kfree(context);
1290 isec->sid = sid;
1291 break;
1292 case SECURITY_FS_USE_TASK:
1293 isec->sid = isec->task_sid;
1294 break;
1295 case SECURITY_FS_USE_TRANS:
1296 /* Default to the fs SID. */
1297 isec->sid = sbsec->sid;
1298
1299 /* Try to obtain a transition SID. */
1300 isec->sclass = inode_mode_to_security_class(inode->i_mode);
1301 rc = security_transition_sid(isec->task_sid, sbsec->sid,
1302 isec->sclass, NULL, &sid);
1303 if (rc)
1304 goto out_unlock;
1305 isec->sid = sid;
1306 break;
1307 case SECURITY_FS_USE_MNTPOINT:
1308 isec->sid = sbsec->mntpoint_sid;
1309 break;
1310 default:
1311 /* Default to the fs superblock SID. */
1312 isec->sid = sbsec->sid;
1313
1314 if ((sbsec->flags & SE_SBPROC) && !S_ISLNK(inode->i_mode)) {
1315 if (opt_dentry) {
1316 isec->sclass = inode_mode_to_security_class(inode->i_mode);
1317 rc = selinux_proc_get_sid(opt_dentry,
1318 isec->sclass,
1319 &sid);
1320 if (rc)
1321 goto out_unlock;
1322 isec->sid = sid;
1323 }
1324 }
1325 break;
1326 }
1327
1328 isec->initialized = 1;
1329
1330 out_unlock:
1331 mutex_unlock(&isec->lock);
1332 out:
1333 if (isec->sclass == SECCLASS_FILE)
1334 isec->sclass = inode_mode_to_security_class(inode->i_mode);
1335 return rc;
1336 }
1337
1338 /* Convert a Linux signal to an access vector. */
1339 static inline u32 signal_to_av(int sig)
1340 {
1341 u32 perm = 0;
1342
1343 switch (sig) {
1344 case SIGCHLD:
1345 /* Commonly granted from child to parent. */
1346 perm = PROCESS__SIGCHLD;
1347 break;
1348 case SIGKILL:
1349 /* Cannot be caught or ignored */
1350 perm = PROCESS__SIGKILL;
1351 break;
1352 case SIGSTOP:
1353 /* Cannot be caught or ignored */
1354 perm = PROCESS__SIGSTOP;
1355 break;
1356 default:
1357 /* All other signals. */
1358 perm = PROCESS__SIGNAL;
1359 break;
1360 }
1361
1362 return perm;
1363 }
1364
1365 /*
1366 * Check permission between a pair of credentials
1367 * fork check, ptrace check, etc.
1368 */
1369 static int cred_has_perm(const struct cred *actor,
1370 const struct cred *target,
1371 u32 perms)
1372 {
1373 u32 asid = cred_sid(actor), tsid = cred_sid(target);
1374
1375 return avc_has_perm(asid, tsid, SECCLASS_PROCESS, perms, NULL);
1376 }
1377
1378 /*
1379 * Check permission between a pair of tasks, e.g. signal checks,
1380 * fork check, ptrace check, etc.
1381 * tsk1 is the actor and tsk2 is the target
1382 * - this uses the default subjective creds of tsk1
1383 */
1384 static int task_has_perm(const struct task_struct *tsk1,
1385 const struct task_struct *tsk2,
1386 u32 perms)
1387 {
1388 const struct task_security_struct *__tsec1, *__tsec2;
1389 u32 sid1, sid2;
1390
1391 rcu_read_lock();
1392 __tsec1 = __task_cred(tsk1)->security; sid1 = __tsec1->sid;
1393 __tsec2 = __task_cred(tsk2)->security; sid2 = __tsec2->sid;
1394 rcu_read_unlock();
1395 return avc_has_perm(sid1, sid2, SECCLASS_PROCESS, perms, NULL);
1396 }
1397
1398 /*
1399 * Check permission between current and another task, e.g. signal checks,
1400 * fork check, ptrace check, etc.
1401 * current is the actor and tsk2 is the target
1402 * - this uses current's subjective creds
1403 */
1404 static int current_has_perm(const struct task_struct *tsk,
1405 u32 perms)
1406 {
1407 u32 sid, tsid;
1408
1409 sid = current_sid();
1410 tsid = task_sid(tsk);
1411 return avc_has_perm(sid, tsid, SECCLASS_PROCESS, perms, NULL);
1412 }
1413
1414 #if CAP_LAST_CAP > 63
1415 #error Fix SELinux to handle capabilities > 63.
1416 #endif
1417
1418 /* Check whether a task is allowed to use a capability. */
1419 static int cred_has_capability(const struct cred *cred,
1420 int cap, int audit)
1421 {
1422 struct common_audit_data ad;
1423 struct av_decision avd;
1424 u16 sclass;
1425 u32 sid = cred_sid(cred);
1426 u32 av = CAP_TO_MASK(cap);
1427 int rc;
1428
1429 ad.type = LSM_AUDIT_DATA_CAP;
1430 ad.u.cap = cap;
1431
1432 switch (CAP_TO_INDEX(cap)) {
1433 case 0:
1434 sclass = SECCLASS_CAPABILITY;
1435 break;
1436 case 1:
1437 sclass = SECCLASS_CAPABILITY2;
1438 break;
1439 default:
1440 printk(KERN_ERR
1441 "SELinux: out of range capability %d\n", cap);
1442 BUG();
1443 return -EINVAL;
1444 }
1445
1446 rc = avc_has_perm_noaudit(sid, sid, sclass, av, 0, &avd);
1447 if (audit == SECURITY_CAP_AUDIT) {
1448 int rc2 = avc_audit(sid, sid, sclass, av, &avd, rc, &ad, 0);
1449 if (rc2)
1450 return rc2;
1451 }
1452 return rc;
1453 }
1454
1455 /* Check whether a task is allowed to use a system operation. */
1456 static int task_has_system(struct task_struct *tsk,
1457 u32 perms)
1458 {
1459 u32 sid = task_sid(tsk);
1460
1461 return avc_has_perm(sid, SECINITSID_KERNEL,
1462 SECCLASS_SYSTEM, perms, NULL);
1463 }
1464
1465 /* Check whether a task has a particular permission to an inode.
1466 The 'adp' parameter is optional and allows other audit
1467 data to be passed (e.g. the dentry). */
1468 static int inode_has_perm(const struct cred *cred,
1469 struct inode *inode,
1470 u32 perms,
1471 struct common_audit_data *adp,
1472 unsigned flags)
1473 {
1474 struct inode_security_struct *isec;
1475 u32 sid;
1476
1477 validate_creds(cred);
1478
1479 if (unlikely(IS_PRIVATE(inode)))
1480 return 0;
1481
1482 sid = cred_sid(cred);
1483 isec = inode->i_security;
1484
1485 return avc_has_perm_flags(sid, isec->sid, isec->sclass, perms, adp, flags);
1486 }
1487
1488 /* Same as inode_has_perm, but pass explicit audit data containing
1489 the dentry to help the auditing code to more easily generate the
1490 pathname if needed. */
1491 static inline int dentry_has_perm(const struct cred *cred,
1492 struct dentry *dentry,
1493 u32 av)
1494 {
1495 struct inode *inode = dentry->d_inode;
1496 struct common_audit_data ad;
1497
1498 ad.type = LSM_AUDIT_DATA_DENTRY;
1499 ad.u.dentry = dentry;
1500 return inode_has_perm(cred, inode, av, &ad, 0);
1501 }
1502
1503 /* Same as inode_has_perm, but pass explicit audit data containing
1504 the path to help the auditing code to more easily generate the
1505 pathname if needed. */
1506 static inline int path_has_perm(const struct cred *cred,
1507 struct path *path,
1508 u32 av)
1509 {
1510 struct inode *inode = path->dentry->d_inode;
1511 struct common_audit_data ad;
1512
1513 ad.type = LSM_AUDIT_DATA_PATH;
1514 ad.u.path = *path;
1515 return inode_has_perm(cred, inode, av, &ad, 0);
1516 }
1517
1518 /* Check whether a task can use an open file descriptor to
1519 access an inode in a given way. Check access to the
1520 descriptor itself, and then use dentry_has_perm to
1521 check a particular permission to the file.
1522 Access to the descriptor is implicitly granted if it
1523 has the same SID as the process. If av is zero, then
1524 access to the file is not checked, e.g. for cases
1525 where only the descriptor is affected like seek. */
1526 static int file_has_perm(const struct cred *cred,
1527 struct file *file,
1528 u32 av)
1529 {
1530 struct file_security_struct *fsec = file->f_security;
1531 struct inode *inode = file_inode(file);
1532 struct common_audit_data ad;
1533 u32 sid = cred_sid(cred);
1534 int rc;
1535
1536 ad.type = LSM_AUDIT_DATA_PATH;
1537 ad.u.path = file->f_path;
1538
1539 if (sid != fsec->sid) {
1540 rc = avc_has_perm(sid, fsec->sid,
1541 SECCLASS_FD,
1542 FD__USE,
1543 &ad);
1544 if (rc)
1545 goto out;
1546 }
1547
1548 /* av is zero if only checking access to the descriptor. */
1549 rc = 0;
1550 if (av)
1551 rc = inode_has_perm(cred, inode, av, &ad, 0);
1552
1553 out:
1554 return rc;
1555 }
1556
1557 /* Check whether a task can create a file. */
1558 static int may_create(struct inode *dir,
1559 struct dentry *dentry,
1560 u16 tclass)
1561 {
1562 const struct task_security_struct *tsec = current_security();
1563 struct inode_security_struct *dsec;
1564 struct superblock_security_struct *sbsec;
1565 u32 sid, newsid;
1566 struct common_audit_data ad;
1567 int rc;
1568
1569 dsec = dir->i_security;
1570 sbsec = dir->i_sb->s_security;
1571
1572 sid = tsec->sid;
1573 newsid = tsec->create_sid;
1574
1575 ad.type = LSM_AUDIT_DATA_DENTRY;
1576 ad.u.dentry = dentry;
1577
1578 rc = avc_has_perm(sid, dsec->sid, SECCLASS_DIR,
1579 DIR__ADD_NAME | DIR__SEARCH,
1580 &ad);
1581 if (rc)
1582 return rc;
1583
1584 if (!newsid || !(sbsec->flags & SE_SBLABELSUPP)) {
1585 rc = security_transition_sid(sid, dsec->sid, tclass,
1586 &dentry->d_name, &newsid);
1587 if (rc)
1588 return rc;
1589 }
1590
1591 rc = avc_has_perm(sid, newsid, tclass, FILE__CREATE, &ad);
1592 if (rc)
1593 return rc;
1594
1595 return avc_has_perm(newsid, sbsec->sid,
1596 SECCLASS_FILESYSTEM,
1597 FILESYSTEM__ASSOCIATE, &ad);
1598 }
1599
1600 /* Check whether a task can create a key. */
1601 static int may_create_key(u32 ksid,
1602 struct task_struct *ctx)
1603 {
1604 u32 sid = task_sid(ctx);
1605
1606 return avc_has_perm(sid, ksid, SECCLASS_KEY, KEY__CREATE, NULL);
1607 }
1608
1609 #define MAY_LINK 0
1610 #define MAY_UNLINK 1
1611 #define MAY_RMDIR 2
1612
1613 /* Check whether a task can link, unlink, or rmdir a file/directory. */
1614 static int may_link(struct inode *dir,
1615 struct dentry *dentry,
1616 int kind)
1617
1618 {
1619 struct inode_security_struct *dsec, *isec;
1620 struct common_audit_data ad;
1621 u32 sid = current_sid();
1622 u32 av;
1623 int rc;
1624
1625 dsec = dir->i_security;
1626 isec = dentry->d_inode->i_security;
1627
1628 ad.type = LSM_AUDIT_DATA_DENTRY;
1629 ad.u.dentry = dentry;
1630
1631 av = DIR__SEARCH;
1632 av |= (kind ? DIR__REMOVE_NAME : DIR__ADD_NAME);
1633 rc = avc_has_perm(sid, dsec->sid, SECCLASS_DIR, av, &ad);
1634 if (rc)
1635 return rc;
1636
1637 switch (kind) {
1638 case MAY_LINK:
1639 av = FILE__LINK;
1640 break;
1641 case MAY_UNLINK:
1642 av = FILE__UNLINK;
1643 break;
1644 case MAY_RMDIR:
1645 av = DIR__RMDIR;
1646 break;
1647 default:
1648 printk(KERN_WARNING "SELinux: %s: unrecognized kind %d\n",
1649 __func__, kind);
1650 return 0;
1651 }
1652
1653 rc = avc_has_perm(sid, isec->sid, isec->sclass, av, &ad);
1654 return rc;
1655 }
1656
1657 static inline int may_rename(struct inode *old_dir,
1658 struct dentry *old_dentry,
1659 struct inode *new_dir,
1660 struct dentry *new_dentry)
1661 {
1662 struct inode_security_struct *old_dsec, *new_dsec, *old_isec, *new_isec;
1663 struct common_audit_data ad;
1664 u32 sid = current_sid();
1665 u32 av;
1666 int old_is_dir, new_is_dir;
1667 int rc;
1668
1669 old_dsec = old_dir->i_security;
1670 old_isec = old_dentry->d_inode->i_security;
1671 old_is_dir = S_ISDIR(old_dentry->d_inode->i_mode);
1672 new_dsec = new_dir->i_security;
1673
1674 ad.type = LSM_AUDIT_DATA_DENTRY;
1675
1676 ad.u.dentry = old_dentry;
1677 rc = avc_has_perm(sid, old_dsec->sid, SECCLASS_DIR,
1678 DIR__REMOVE_NAME | DIR__SEARCH, &ad);
1679 if (rc)
1680 return rc;
1681 rc = avc_has_perm(sid, old_isec->sid,
1682 old_isec->sclass, FILE__RENAME, &ad);
1683 if (rc)
1684 return rc;
1685 if (old_is_dir && new_dir != old_dir) {
1686 rc = avc_has_perm(sid, old_isec->sid,
1687 old_isec->sclass, DIR__REPARENT, &ad);
1688 if (rc)
1689 return rc;
1690 }
1691
1692 ad.u.dentry = new_dentry;
1693 av = DIR__ADD_NAME | DIR__SEARCH;
1694 if (new_dentry->d_inode)
1695 av |= DIR__REMOVE_NAME;
1696 rc = avc_has_perm(sid, new_dsec->sid, SECCLASS_DIR, av, &ad);
1697 if (rc)
1698 return rc;
1699 if (new_dentry->d_inode) {
1700 new_isec = new_dentry->d_inode->i_security;
1701 new_is_dir = S_ISDIR(new_dentry->d_inode->i_mode);
1702 rc = avc_has_perm(sid, new_isec->sid,
1703 new_isec->sclass,
1704 (new_is_dir ? DIR__RMDIR : FILE__UNLINK), &ad);
1705 if (rc)
1706 return rc;
1707 }
1708
1709 return 0;
1710 }
1711
1712 /* Check whether a task can perform a filesystem operation. */
1713 static int superblock_has_perm(const struct cred *cred,
1714 struct super_block *sb,
1715 u32 perms,
1716 struct common_audit_data *ad)
1717 {
1718 struct superblock_security_struct *sbsec;
1719 u32 sid = cred_sid(cred);
1720
1721 sbsec = sb->s_security;
1722 return avc_has_perm(sid, sbsec->sid, SECCLASS_FILESYSTEM, perms, ad);
1723 }
1724
1725 /* Convert a Linux mode and permission mask to an access vector. */
1726 static inline u32 file_mask_to_av(int mode, int mask)
1727 {
1728 u32 av = 0;
1729
1730 if (!S_ISDIR(mode)) {
1731 if (mask & MAY_EXEC)
1732 av |= FILE__EXECUTE;
1733 if (mask & MAY_READ)
1734 av |= FILE__READ;
1735
1736 if (mask & MAY_APPEND)
1737 av |= FILE__APPEND;
1738 else if (mask & MAY_WRITE)
1739 av |= FILE__WRITE;
1740
1741 } else {
1742 if (mask & MAY_EXEC)
1743 av |= DIR__SEARCH;
1744 if (mask & MAY_WRITE)
1745 av |= DIR__WRITE;
1746 if (mask & MAY_READ)
1747 av |= DIR__READ;
1748 }
1749
1750 return av;
1751 }
1752
1753 /* Convert a Linux file to an access vector. */
1754 static inline u32 file_to_av(struct file *file)
1755 {
1756 u32 av = 0;
1757
1758 if (file->f_mode & FMODE_READ)
1759 av |= FILE__READ;
1760 if (file->f_mode & FMODE_WRITE) {
1761 if (file->f_flags & O_APPEND)
1762 av |= FILE__APPEND;
1763 else
1764 av |= FILE__WRITE;
1765 }
1766 if (!av) {
1767 /*
1768 * Special file opened with flags 3 for ioctl-only use.
1769 */
1770 av = FILE__IOCTL;
1771 }
1772
1773 return av;
1774 }
1775
1776 /*
1777 * Convert a file to an access vector and include the correct open
1778 * open permission.
1779 */
1780 static inline u32 open_file_to_av(struct file *file)
1781 {
1782 u32 av = file_to_av(file);
1783
1784 if (selinux_policycap_openperm)
1785 av |= FILE__OPEN;
1786
1787 return av;
1788 }
1789
1790 /* Hook functions begin here. */
1791
1792 static int selinux_ptrace_access_check(struct task_struct *child,
1793 unsigned int mode)
1794 {
1795 int rc;
1796
1797 rc = cap_ptrace_access_check(child, mode);
1798 if (rc)
1799 return rc;
1800
1801 if (mode & PTRACE_MODE_READ) {
1802 u32 sid = current_sid();
1803 u32 csid = task_sid(child);
1804 return avc_has_perm(sid, csid, SECCLASS_FILE, FILE__READ, NULL);
1805 }
1806
1807 return current_has_perm(child, PROCESS__PTRACE);
1808 }
1809
1810 static int selinux_ptrace_traceme(struct task_struct *parent)
1811 {
1812 int rc;
1813
1814 rc = cap_ptrace_traceme(parent);
1815 if (rc)
1816 return rc;
1817
1818 return task_has_perm(parent, current, PROCESS__PTRACE);
1819 }
1820
1821 static int selinux_capget(struct task_struct *target, kernel_cap_t *effective,
1822 kernel_cap_t *inheritable, kernel_cap_t *permitted)
1823 {
1824 int error;
1825
1826 error = current_has_perm(target, PROCESS__GETCAP);
1827 if (error)
1828 return error;
1829
1830 return cap_capget(target, effective, inheritable, permitted);
1831 }
1832
1833 static int selinux_capset(struct cred *new, const struct cred *old,
1834 const kernel_cap_t *effective,
1835 const kernel_cap_t *inheritable,
1836 const kernel_cap_t *permitted)
1837 {
1838 int error;
1839
1840 error = cap_capset(new, old,
1841 effective, inheritable, permitted);
1842 if (error)
1843 return error;
1844
1845 return cred_has_perm(old, new, PROCESS__SETCAP);
1846 }
1847
1848 /*
1849 * (This comment used to live with the selinux_task_setuid hook,
1850 * which was removed).
1851 *
1852 * Since setuid only affects the current process, and since the SELinux
1853 * controls are not based on the Linux identity attributes, SELinux does not
1854 * need to control this operation. However, SELinux does control the use of
1855 * the CAP_SETUID and CAP_SETGID capabilities using the capable hook.
1856 */
1857
1858 static int selinux_capable(const struct cred *cred, struct user_namespace *ns,
1859 int cap, int audit)
1860 {
1861 int rc;
1862
1863 rc = cap_capable(cred, ns, cap, audit);
1864 if (rc)
1865 return rc;
1866
1867 return cred_has_capability(cred, cap, audit);
1868 }
1869
1870 static int selinux_quotactl(int cmds, int type, int id, struct super_block *sb)
1871 {
1872 const struct cred *cred = current_cred();
1873 int rc = 0;
1874
1875 if (!sb)
1876 return 0;
1877
1878 switch (cmds) {
1879 case Q_SYNC:
1880 case Q_QUOTAON:
1881 case Q_QUOTAOFF:
1882 case Q_SETINFO:
1883 case Q_SETQUOTA:
1884 rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAMOD, NULL);
1885 break;
1886 case Q_GETFMT:
1887 case Q_GETINFO:
1888 case Q_GETQUOTA:
1889 rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAGET, NULL);
1890 break;
1891 default:
1892 rc = 0; /* let the kernel handle invalid cmds */
1893 break;
1894 }
1895 return rc;
1896 }
1897
1898 static int selinux_quota_on(struct dentry *dentry)
1899 {
1900 const struct cred *cred = current_cred();
1901
1902 return dentry_has_perm(cred, dentry, FILE__QUOTAON);
1903 }
1904
1905 static int selinux_syslog(int type)
1906 {
1907 int rc;
1908
1909 switch (type) {
1910 case SYSLOG_ACTION_READ_ALL: /* Read last kernel messages */
1911 case SYSLOG_ACTION_SIZE_BUFFER: /* Return size of the log buffer */
1912 rc = task_has_system(current, SYSTEM__SYSLOG_READ);
1913 break;
1914 case SYSLOG_ACTION_CONSOLE_OFF: /* Disable logging to console */
1915 case SYSLOG_ACTION_CONSOLE_ON: /* Enable logging to console */
1916 /* Set level of messages printed to console */
1917 case SYSLOG_ACTION_CONSOLE_LEVEL:
1918 rc = task_has_system(current, SYSTEM__SYSLOG_CONSOLE);
1919 break;
1920 case SYSLOG_ACTION_CLOSE: /* Close log */
1921 case SYSLOG_ACTION_OPEN: /* Open log */
1922 case SYSLOG_ACTION_READ: /* Read from log */
1923 case SYSLOG_ACTION_READ_CLEAR: /* Read/clear last kernel messages */
1924 case SYSLOG_ACTION_CLEAR: /* Clear ring buffer */
1925 default:
1926 rc = task_has_system(current, SYSTEM__SYSLOG_MOD);
1927 break;
1928 }
1929 return rc;
1930 }
1931
1932 /*
1933 * Check that a process has enough memory to allocate a new virtual
1934 * mapping. 0 means there is enough memory for the allocation to
1935 * succeed and -ENOMEM implies there is not.
1936 *
1937 * Do not audit the selinux permission check, as this is applied to all
1938 * processes that allocate mappings.
1939 */
1940 static int selinux_vm_enough_memory(struct mm_struct *mm, long pages)
1941 {
1942 int rc, cap_sys_admin = 0;
1943
1944 rc = selinux_capable(current_cred(), &init_user_ns, CAP_SYS_ADMIN,
1945 SECURITY_CAP_NOAUDIT);
1946 if (rc == 0)
1947 cap_sys_admin = 1;
1948
1949 return __vm_enough_memory(mm, pages, cap_sys_admin);
1950 }
1951
1952 /* binprm security operations */
1953
1954 static int selinux_bprm_set_creds(struct linux_binprm *bprm)
1955 {
1956 const struct task_security_struct *old_tsec;
1957 struct task_security_struct *new_tsec;
1958 struct inode_security_struct *isec;
1959 struct common_audit_data ad;
1960 struct inode *inode = file_inode(bprm->file);
1961 int rc;
1962
1963 rc = cap_bprm_set_creds(bprm);
1964 if (rc)
1965 return rc;
1966
1967 /* SELinux context only depends on initial program or script and not
1968 * the script interpreter */
1969 if (bprm->cred_prepared)
1970 return 0;
1971
1972 old_tsec = current_security();
1973 new_tsec = bprm->cred->security;
1974 isec = inode->i_security;
1975
1976 /* Default to the current task SID. */
1977 new_tsec->sid = old_tsec->sid;
1978 new_tsec->osid = old_tsec->sid;
1979
1980 /* Reset fs, key, and sock SIDs on execve. */
1981 new_tsec->create_sid = 0;
1982 new_tsec->keycreate_sid = 0;
1983 new_tsec->sockcreate_sid = 0;
1984
1985 if (old_tsec->exec_sid) {
1986 new_tsec->sid = old_tsec->exec_sid;
1987 /* Reset exec SID on execve. */
1988 new_tsec->exec_sid = 0;
1989
1990 /*
1991 * Minimize confusion: if no_new_privs and a transition is
1992 * explicitly requested, then fail the exec.
1993 */
1994 if (bprm->unsafe & LSM_UNSAFE_NO_NEW_PRIVS)
1995 return -EPERM;
1996 } else {
1997 /* Check for a default transition on this program. */
1998 rc = security_transition_sid(old_tsec->sid, isec->sid,
1999 SECCLASS_PROCESS, NULL,
2000 &new_tsec->sid);
2001 if (rc)
2002 return rc;
2003 }
2004
2005 ad.type = LSM_AUDIT_DATA_PATH;
2006 ad.u.path = bprm->file->f_path;
2007
2008 if ((bprm->file->f_path.mnt->mnt_flags & MNT_NOSUID) ||
2009 (bprm->unsafe & LSM_UNSAFE_NO_NEW_PRIVS))
2010 new_tsec->sid = old_tsec->sid;
2011
2012 if (new_tsec->sid == old_tsec->sid) {
2013 rc = avc_has_perm(old_tsec->sid, isec->sid,
2014 SECCLASS_FILE, FILE__EXECUTE_NO_TRANS, &ad);
2015 if (rc)
2016 return rc;
2017 } else {
2018 /* Check permissions for the transition. */
2019 rc = avc_has_perm(old_tsec->sid, new_tsec->sid,
2020 SECCLASS_PROCESS, PROCESS__TRANSITION, &ad);
2021 if (rc)
2022 return rc;
2023
2024 rc = avc_has_perm(new_tsec->sid, isec->sid,
2025 SECCLASS_FILE, FILE__ENTRYPOINT, &ad);
2026 if (rc)
2027 return rc;
2028
2029 /* Check for shared state */
2030 if (bprm->unsafe & LSM_UNSAFE_SHARE) {
2031 rc = avc_has_perm(old_tsec->sid, new_tsec->sid,
2032 SECCLASS_PROCESS, PROCESS__SHARE,
2033 NULL);
2034 if (rc)
2035 return -EPERM;
2036 }
2037
2038 /* Make sure that anyone attempting to ptrace over a task that
2039 * changes its SID has the appropriate permit */
2040 if (bprm->unsafe &
2041 (LSM_UNSAFE_PTRACE | LSM_UNSAFE_PTRACE_CAP)) {
2042 struct task_struct *tracer;
2043 struct task_security_struct *sec;
2044 u32 ptsid = 0;
2045
2046 rcu_read_lock();
2047 tracer = ptrace_parent(current);
2048 if (likely(tracer != NULL)) {
2049 sec = __task_cred(tracer)->security;
2050 ptsid = sec->sid;
2051 }
2052 rcu_read_unlock();
2053
2054 if (ptsid != 0) {
2055 rc = avc_has_perm(ptsid, new_tsec->sid,
2056 SECCLASS_PROCESS,
2057 PROCESS__PTRACE, NULL);
2058 if (rc)
2059 return -EPERM;
2060 }
2061 }
2062
2063 /* Clear any possibly unsafe personality bits on exec: */
2064 bprm->per_clear |= PER_CLEAR_ON_SETID;
2065 }
2066
2067 return 0;
2068 }
2069
2070 static int selinux_bprm_secureexec(struct linux_binprm *bprm)
2071 {
2072 const struct task_security_struct *tsec = current_security();
2073 u32 sid, osid;
2074 int atsecure = 0;
2075
2076 sid = tsec->sid;
2077 osid = tsec->osid;
2078
2079 if (osid != sid) {
2080 /* Enable secure mode for SIDs transitions unless
2081 the noatsecure permission is granted between
2082 the two SIDs, i.e. ahp returns 0. */
2083 atsecure = avc_has_perm(osid, sid,
2084 SECCLASS_PROCESS,
2085 PROCESS__NOATSECURE, NULL);
2086 }
2087
2088 return (atsecure || cap_bprm_secureexec(bprm));
2089 }
2090
2091 static int match_file(const void *p, struct file *file, unsigned fd)
2092 {
2093 return file_has_perm(p, file, file_to_av(file)) ? fd + 1 : 0;
2094 }
2095
2096 /* Derived from fs/exec.c:flush_old_files. */
2097 static inline void flush_unauthorized_files(const struct cred *cred,
2098 struct files_struct *files)
2099 {
2100 struct file *file, *devnull = NULL;
2101 struct tty_struct *tty;
2102 int drop_tty = 0;
2103 unsigned n;
2104
2105 tty = get_current_tty();
2106 if (tty) {
2107 spin_lock(&tty_files_lock);
2108 if (!list_empty(&tty->tty_files)) {
2109 struct tty_file_private *file_priv;
2110
2111 /* Revalidate access to controlling tty.
2112 Use path_has_perm on the tty path directly rather
2113 than using file_has_perm, as this particular open
2114 file may belong to another process and we are only
2115 interested in the inode-based check here. */
2116 file_priv = list_first_entry(&tty->tty_files,
2117 struct tty_file_private, list);
2118 file = file_priv->file;
2119 if (path_has_perm(cred, &file->f_path, FILE__READ | FILE__WRITE))
2120 drop_tty = 1;
2121 }
2122 spin_unlock(&tty_files_lock);
2123 tty_kref_put(tty);
2124 }
2125 /* Reset controlling tty. */
2126 if (drop_tty)
2127 no_tty();
2128
2129 /* Revalidate access to inherited open files. */
2130 n = iterate_fd(files, 0, match_file, cred);
2131 if (!n) /* none found? */
2132 return;
2133
2134 devnull = dentry_open(&selinux_null, O_RDWR, cred);
2135 if (IS_ERR(devnull))
2136 devnull = NULL;
2137 /* replace all the matching ones with this */
2138 do {
2139 replace_fd(n - 1, devnull, 0);
2140 } while ((n = iterate_fd(files, n, match_file, cred)) != 0);
2141 if (devnull)
2142 fput(devnull);
2143 }
2144
2145 /*
2146 * Prepare a process for imminent new credential changes due to exec
2147 */
2148 static void selinux_bprm_committing_creds(struct linux_binprm *bprm)
2149 {
2150 struct task_security_struct *new_tsec;
2151 struct rlimit *rlim, *initrlim;
2152 int rc, i;
2153
2154 new_tsec = bprm->cred->security;
2155 if (new_tsec->sid == new_tsec->osid)
2156 return;
2157
2158 /* Close files for which the new task SID is not authorized. */
2159 flush_unauthorized_files(bprm->cred, current->files);
2160
2161 /* Always clear parent death signal on SID transitions. */
2162 current->pdeath_signal = 0;
2163
2164 /* Check whether the new SID can inherit resource limits from the old
2165 * SID. If not, reset all soft limits to the lower of the current
2166 * task's hard limit and the init task's soft limit.
2167 *
2168 * Note that the setting of hard limits (even to lower them) can be
2169 * controlled by the setrlimit check. The inclusion of the init task's
2170 * soft limit into the computation is to avoid resetting soft limits
2171 * higher than the default soft limit for cases where the default is
2172 * lower than the hard limit, e.g. RLIMIT_CORE or RLIMIT_STACK.
2173 */
2174 rc = avc_has_perm(new_tsec->osid, new_tsec->sid, SECCLASS_PROCESS,
2175 PROCESS__RLIMITINH, NULL);
2176 if (rc) {
2177 /* protect against do_prlimit() */
2178 task_lock(current);
2179 for (i = 0; i < RLIM_NLIMITS; i++) {
2180 rlim = current->signal->rlim + i;
2181 initrlim = init_task.signal->rlim + i;
2182 rlim->rlim_cur = min(rlim->rlim_max, initrlim->rlim_cur);
2183 }
2184 task_unlock(current);
2185 update_rlimit_cpu(current, rlimit(RLIMIT_CPU));
2186 }
2187 }
2188
2189 /*
2190 * Clean up the process immediately after the installation of new credentials
2191 * due to exec
2192 */
2193 static void selinux_bprm_committed_creds(struct linux_binprm *bprm)
2194 {
2195 const struct task_security_struct *tsec = current_security();
2196 struct itimerval itimer;
2197 u32 osid, sid;
2198 int rc, i;
2199
2200 osid = tsec->osid;
2201 sid = tsec->sid;
2202
2203 if (sid == osid)
2204 return;
2205
2206 /* Check whether the new SID can inherit signal state from the old SID.
2207 * If not, clear itimers to avoid subsequent signal generation and
2208 * flush and unblock signals.
2209 *
2210 * This must occur _after_ the task SID has been updated so that any
2211 * kill done after the flush will be checked against the new SID.
2212 */
2213 rc = avc_has_perm(osid, sid, SECCLASS_PROCESS, PROCESS__SIGINH, NULL);
2214 if (rc) {
2215 memset(&itimer, 0, sizeof itimer);
2216 for (i = 0; i < 3; i++)
2217 do_setitimer(i, &itimer, NULL);
2218 spin_lock_irq(&current->sighand->siglock);
2219 if (!(current->signal->flags & SIGNAL_GROUP_EXIT)) {
2220 __flush_signals(current);
2221 flush_signal_handlers(current, 1);
2222 sigemptyset(&current->blocked);
2223 }
2224 spin_unlock_irq(&current->sighand->siglock);
2225 }
2226
2227 /* Wake up the parent if it is waiting so that it can recheck
2228 * wait permission to the new task SID. */
2229 read_lock(&tasklist_lock);
2230 __wake_up_parent(current, current->real_parent);
2231 read_unlock(&tasklist_lock);
2232 }
2233
2234 /* superblock security operations */
2235
2236 static int selinux_sb_alloc_security(struct super_block *sb)
2237 {
2238 return superblock_alloc_security(sb);
2239 }
2240
2241 static void selinux_sb_free_security(struct super_block *sb)
2242 {
2243 superblock_free_security(sb);
2244 }
2245
2246 static inline int match_prefix(char *prefix, int plen, char *option, int olen)
2247 {
2248 if (plen > olen)
2249 return 0;
2250
2251 return !memcmp(prefix, option, plen);
2252 }
2253
2254 static inline int selinux_option(char *option, int len)
2255 {
2256 return (match_prefix(CONTEXT_STR, sizeof(CONTEXT_STR)-1, option, len) ||
2257 match_prefix(FSCONTEXT_STR, sizeof(FSCONTEXT_STR)-1, option, len) ||
2258 match_prefix(DEFCONTEXT_STR, sizeof(DEFCONTEXT_STR)-1, option, len) ||
2259 match_prefix(ROOTCONTEXT_STR, sizeof(ROOTCONTEXT_STR)-1, option, len) ||
2260 match_prefix(LABELSUPP_STR, sizeof(LABELSUPP_STR)-1, option, len));
2261 }
2262
2263 static inline void take_option(char **to, char *from, int *first, int len)
2264 {
2265 if (!*first) {
2266 **to = ',';
2267 *to += 1;
2268 } else
2269 *first = 0;
2270 memcpy(*to, from, len);
2271 *to += len;
2272 }
2273
2274 static inline void take_selinux_option(char **to, char *from, int *first,
2275 int len)
2276 {
2277 int current_size = 0;
2278
2279 if (!*first) {
2280 **to = '|';
2281 *to += 1;
2282 } else
2283 *first = 0;
2284
2285 while (current_size < len) {
2286 if (*from != '"') {
2287 **to = *from;
2288 *to += 1;
2289 }
2290 from += 1;
2291 current_size += 1;
2292 }
2293 }
2294
2295 static int selinux_sb_copy_data(char *orig, char *copy)
2296 {
2297 int fnosec, fsec, rc = 0;
2298 char *in_save, *in_curr, *in_end;
2299 char *sec_curr, *nosec_save, *nosec;
2300 int open_quote = 0;
2301
2302 in_curr = orig;
2303 sec_curr = copy;
2304
2305 nosec = (char *)get_zeroed_page(GFP_KERNEL);
2306 if (!nosec) {
2307 rc = -ENOMEM;
2308 goto out;
2309 }
2310
2311 nosec_save = nosec;
2312 fnosec = fsec = 1;
2313 in_save = in_end = orig;
2314
2315 do {
2316 if (*in_end == '"')
2317 open_quote = !open_quote;
2318 if ((*in_end == ',' && open_quote == 0) ||
2319 *in_end == '\0') {
2320 int len = in_end - in_curr;
2321
2322 if (selinux_option(in_curr, len))
2323 take_selinux_option(&sec_curr, in_curr, &fsec, len);
2324 else
2325 take_option(&nosec, in_curr, &fnosec, len);
2326
2327 in_curr = in_end + 1;
2328 }
2329 } while (*in_end++);
2330
2331 strcpy(in_save, nosec_save);
2332 free_page((unsigned long)nosec_save);
2333 out:
2334 return rc;
2335 }
2336
2337 static int selinux_sb_remount(struct super_block *sb, void *data)
2338 {
2339 int rc, i, *flags;
2340 struct security_mnt_opts opts;
2341 char *secdata, **mount_options;
2342 struct superblock_security_struct *sbsec = sb->s_security;
2343
2344 if (!(sbsec->flags & SE_SBINITIALIZED))
2345 return 0;
2346
2347 if (!data)
2348 return 0;
2349
2350 if (sb->s_type->fs_flags & FS_BINARY_MOUNTDATA)
2351 return 0;
2352
2353 security_init_mnt_opts(&opts);
2354 secdata = alloc_secdata();
2355 if (!secdata)
2356 return -ENOMEM;
2357 rc = selinux_sb_copy_data(data, secdata);
2358 if (rc)
2359 goto out_free_secdata;
2360
2361 rc = selinux_parse_opts_str(secdata, &opts);
2362 if (rc)
2363 goto out_free_secdata;
2364
2365 mount_options = opts.mnt_opts;
2366 flags = opts.mnt_opts_flags;
2367
2368 for (i = 0; i < opts.num_mnt_opts; i++) {
2369 u32 sid;
2370 size_t len;
2371
2372 if (flags[i] == SE_SBLABELSUPP)
2373 continue;
2374 len = strlen(mount_options[i]);
2375 rc = security_context_to_sid(mount_options[i], len, &sid);
2376 if (rc) {
2377 printk(KERN_WARNING "SELinux: security_context_to_sid"
2378 "(%s) failed for (dev %s, type %s) errno=%d\n",
2379 mount_options[i], sb->s_id, sb->s_type->name, rc);
2380 goto out_free_opts;
2381 }
2382 rc = -EINVAL;
2383 switch (flags[i]) {
2384 case FSCONTEXT_MNT:
2385 if (bad_option(sbsec, FSCONTEXT_MNT, sbsec->sid, sid))
2386 goto out_bad_option;
2387 break;
2388 case CONTEXT_MNT:
2389 if (bad_option(sbsec, CONTEXT_MNT, sbsec->mntpoint_sid, sid))
2390 goto out_bad_option;
2391 break;
2392 case ROOTCONTEXT_MNT: {
2393 struct inode_security_struct *root_isec;
2394 root_isec = sb->s_root->d_inode->i_security;
2395
2396 if (bad_option(sbsec, ROOTCONTEXT_MNT, root_isec->sid, sid))
2397 goto out_bad_option;
2398 break;
2399 }
2400 case DEFCONTEXT_MNT:
2401 if (bad_option(sbsec, DEFCONTEXT_MNT, sbsec->def_sid, sid))
2402 goto out_bad_option;
2403 break;
2404 default:
2405 goto out_free_opts;
2406 }
2407 }
2408
2409 rc = 0;
2410 out_free_opts:
2411 security_free_mnt_opts(&opts);
2412 out_free_secdata:
2413 free_secdata(secdata);
2414 return rc;
2415 out_bad_option:
2416 printk(KERN_WARNING "SELinux: unable to change security options "
2417 "during remount (dev %s, type=%s)\n", sb->s_id,
2418 sb->s_type->name);
2419 goto out_free_opts;
2420 }
2421
2422 static int selinux_sb_kern_mount(struct super_block *sb, int flags, void *data)
2423 {
2424 const struct cred *cred = current_cred();
2425 struct common_audit_data ad;
2426 int rc;
2427
2428 rc = superblock_doinit(sb, data);
2429 if (rc)
2430 return rc;
2431
2432 /* Allow all mounts performed by the kernel */
2433 if (flags & MS_KERNMOUNT)
2434 return 0;
2435
2436 ad.type = LSM_AUDIT_DATA_DENTRY;
2437 ad.u.dentry = sb->s_root;
2438 return superblock_has_perm(cred, sb, FILESYSTEM__MOUNT, &ad);
2439 }
2440
2441 static int selinux_sb_statfs(struct dentry *dentry)
2442 {
2443 const struct cred *cred = current_cred();
2444 struct common_audit_data ad;
2445
2446 ad.type = LSM_AUDIT_DATA_DENTRY;
2447 ad.u.dentry = dentry->d_sb->s_root;
2448 return superblock_has_perm(cred, dentry->d_sb, FILESYSTEM__GETATTR, &ad);
2449 }
2450
2451 static int selinux_mount(const char *dev_name,
2452 struct path *path,
2453 const char *type,
2454 unsigned long flags,
2455 void *data)
2456 {
2457 const struct cred *cred = current_cred();
2458
2459 if (flags & MS_REMOUNT)
2460 return superblock_has_perm(cred, path->dentry->d_sb,
2461 FILESYSTEM__REMOUNT, NULL);
2462 else
2463 return path_has_perm(cred, path, FILE__MOUNTON);
2464 }
2465
2466 static int selinux_umount(struct vfsmount *mnt, int flags)
2467 {
2468 const struct cred *cred = current_cred();
2469
2470 return superblock_has_perm(cred, mnt->mnt_sb,
2471 FILESYSTEM__UNMOUNT, NULL);
2472 }
2473
2474 /* inode security operations */
2475
2476 static int selinux_inode_alloc_security(struct inode *inode)
2477 {
2478 return inode_alloc_security(inode);
2479 }
2480
2481 static void selinux_inode_free_security(struct inode *inode)
2482 {
2483 inode_free_security(inode);
2484 }
2485
2486 static int selinux_inode_init_security(struct inode *inode, struct inode *dir,
2487 const struct qstr *qstr, char **name,
2488 void **value, size_t *len)
2489 {
2490 const struct task_security_struct *tsec = current_security();
2491 struct inode_security_struct *dsec;
2492 struct superblock_security_struct *sbsec;
2493 u32 sid, newsid, clen;
2494 int rc;
2495 char *namep = NULL, *context;
2496
2497 dsec = dir->i_security;
2498 sbsec = dir->i_sb->s_security;
2499
2500 sid = tsec->sid;
2501 newsid = tsec->create_sid;
2502
2503 if ((sbsec->flags & SE_SBINITIALIZED) &&
2504 (sbsec->behavior == SECURITY_FS_USE_MNTPOINT))
2505 newsid = sbsec->mntpoint_sid;
2506 else if (!newsid || !(sbsec->flags & SE_SBLABELSUPP)) {
2507 rc = security_transition_sid(sid, dsec->sid,
2508 inode_mode_to_security_class(inode->i_mode),
2509 qstr, &newsid);
2510 if (rc) {
2511 printk(KERN_WARNING "%s: "
2512 "security_transition_sid failed, rc=%d (dev=%s "
2513 "ino=%ld)\n",
2514 __func__,
2515 -rc, inode->i_sb->s_id, inode->i_ino);
2516 return rc;
2517 }
2518 }
2519
2520 /* Possibly defer initialization to selinux_complete_init. */
2521 if (sbsec->flags & SE_SBINITIALIZED) {
2522 struct inode_security_struct *isec = inode->i_security;
2523 isec->sclass = inode_mode_to_security_class(inode->i_mode);
2524 isec->sid = newsid;
2525 isec->initialized = 1;
2526 }
2527
2528 if (!ss_initialized || !(sbsec->flags & SE_SBLABELSUPP))
2529 return -EOPNOTSUPP;
2530
2531 if (name) {
2532 namep = kstrdup(XATTR_SELINUX_SUFFIX, GFP_NOFS);
2533 if (!namep)
2534 return -ENOMEM;
2535 *name = namep;
2536 }
2537
2538 if (value && len) {
2539 rc = security_sid_to_context_force(newsid, &context, &clen);
2540 if (rc) {
2541 kfree(namep);
2542 return rc;
2543 }
2544 *value = context;
2545 *len = clen;
2546 }
2547
2548 return 0;
2549 }
2550
2551 static int selinux_inode_create(struct inode *dir, struct dentry *dentry, umode_t mode)
2552 {
2553 return may_create(dir, dentry, SECCLASS_FILE);
2554 }
2555
2556 static int selinux_inode_link(struct dentry *old_dentry, struct inode *dir, struct dentry *new_dentry)
2557 {
2558 return may_link(dir, old_dentry, MAY_LINK);
2559 }
2560
2561 static int selinux_inode_unlink(struct inode *dir, struct dentry *dentry)
2562 {
2563 return may_link(dir, dentry, MAY_UNLINK);
2564 }
2565
2566 static int selinux_inode_symlink(struct inode *dir, struct dentry *dentry, const char *name)
2567 {
2568 return may_create(dir, dentry, SECCLASS_LNK_FILE);
2569 }
2570
2571 static int selinux_inode_mkdir(struct inode *dir, struct dentry *dentry, umode_t mask)
2572 {
2573 return may_create(dir, dentry, SECCLASS_DIR);
2574 }
2575
2576 static int selinux_inode_rmdir(struct inode *dir, struct dentry *dentry)
2577 {
2578 return may_link(dir, dentry, MAY_RMDIR);
2579 }
2580
2581 static int selinux_inode_mknod(struct inode *dir, struct dentry *dentry, umode_t mode, dev_t dev)
2582 {
2583 return may_create(dir, dentry, inode_mode_to_security_class(mode));
2584 }
2585
2586 static int selinux_inode_rename(struct inode *old_inode, struct dentry *old_dentry,
2587 struct inode *new_inode, struct dentry *new_dentry)
2588 {
2589 return may_rename(old_inode, old_dentry, new_inode, new_dentry);
2590 }
2591
2592 static int selinux_inode_readlink(struct dentry *dentry)
2593 {
2594 const struct cred *cred = current_cred();
2595
2596 return dentry_has_perm(cred, dentry, FILE__READ);
2597 }
2598
2599 static int selinux_inode_follow_link(struct dentry *dentry, struct nameidata *nameidata)
2600 {
2601 const struct cred *cred = current_cred();
2602
2603 return dentry_has_perm(cred, dentry, FILE__READ);
2604 }
2605
2606 static noinline int audit_inode_permission(struct inode *inode,
2607 u32 perms, u32 audited, u32 denied,
2608 unsigned flags)
2609 {
2610 struct common_audit_data ad;
2611 struct inode_security_struct *isec = inode->i_security;
2612 int rc;
2613
2614 ad.type = LSM_AUDIT_DATA_INODE;
2615 ad.u.inode = inode;
2616
2617 rc = slow_avc_audit(current_sid(), isec->sid, isec->sclass, perms,
2618 audited, denied, &ad, flags);
2619 if (rc)
2620 return rc;
2621 return 0;
2622 }
2623
2624 static int selinux_inode_permission(struct inode *inode, int mask)
2625 {
2626 const struct cred *cred = current_cred();
2627 u32 perms;
2628 bool from_access;
2629 unsigned flags = mask & MAY_NOT_BLOCK;
2630 struct inode_security_struct *isec;
2631 u32 sid;
2632 struct av_decision avd;
2633 int rc, rc2;
2634 u32 audited, denied;
2635
2636 from_access = mask & MAY_ACCESS;
2637 mask &= (MAY_READ|MAY_WRITE|MAY_EXEC|MAY_APPEND);
2638
2639 /* No permission to check. Existence test. */
2640 if (!mask)
2641 return 0;
2642
2643 validate_creds(cred);
2644
2645 if (unlikely(IS_PRIVATE(inode)))
2646 return 0;
2647
2648 perms = file_mask_to_av(inode->i_mode, mask);
2649
2650 sid = cred_sid(cred);
2651 isec = inode->i_security;
2652
2653 rc = avc_has_perm_noaudit(sid, isec->sid, isec->sclass, perms, 0, &avd);
2654 audited = avc_audit_required(perms, &avd, rc,
2655 from_access ? FILE__AUDIT_ACCESS : 0,
2656 &denied);
2657 if (likely(!audited))
2658 return rc;
2659
2660 rc2 = audit_inode_permission(inode, perms, audited, denied, flags);
2661 if (rc2)
2662 return rc2;
2663 return rc;
2664 }
2665
2666 static int selinux_inode_setattr(struct dentry *dentry, struct iattr *iattr)
2667 {
2668 const struct cred *cred = current_cred();
2669 unsigned int ia_valid = iattr->ia_valid;
2670 __u32 av = FILE__WRITE;
2671
2672 /* ATTR_FORCE is just used for ATTR_KILL_S[UG]ID. */
2673 if (ia_valid & ATTR_FORCE) {
2674 ia_valid &= ~(ATTR_KILL_SUID | ATTR_KILL_SGID | ATTR_MODE |
2675 ATTR_FORCE);
2676 if (!ia_valid)
2677 return 0;
2678 }
2679
2680 if (ia_valid & (ATTR_MODE | ATTR_UID | ATTR_GID |
2681 ATTR_ATIME_SET | ATTR_MTIME_SET | ATTR_TIMES_SET))
2682 return dentry_has_perm(cred, dentry, FILE__SETATTR);
2683
2684 if (selinux_policycap_openperm && (ia_valid & ATTR_SIZE))
2685 av |= FILE__OPEN;
2686
2687 return dentry_has_perm(cred, dentry, av);
2688 }
2689
2690 static int selinux_inode_getattr(struct vfsmount *mnt, struct dentry *dentry)
2691 {
2692 const struct cred *cred = current_cred();
2693 struct path path;
2694
2695 path.dentry = dentry;
2696 path.mnt = mnt;
2697
2698 return path_has_perm(cred, &path, FILE__GETATTR);
2699 }
2700
2701 static int selinux_inode_setotherxattr(struct dentry *dentry, const char *name)
2702 {
2703 const struct cred *cred = current_cred();
2704
2705 if (!strncmp(name, XATTR_SECURITY_PREFIX,
2706 sizeof XATTR_SECURITY_PREFIX - 1)) {
2707 if (!strcmp(name, XATTR_NAME_CAPS)) {
2708 if (!capable(CAP_SETFCAP))
2709 return -EPERM;
2710 } else if (!capable(CAP_SYS_ADMIN)) {
2711 /* A different attribute in the security namespace.
2712 Restrict to administrator. */
2713 return -EPERM;
2714 }
2715 }
2716
2717 /* Not an attribute we recognize, so just check the
2718 ordinary setattr permission. */
2719 return dentry_has_perm(cred, dentry, FILE__SETATTR);
2720 }
2721
2722 static int selinux_inode_setxattr(struct dentry *dentry, const char *name,
2723 const void *value, size_t size, int flags)
2724 {
2725 struct inode *inode = dentry->d_inode;
2726 struct inode_security_struct *isec = inode->i_security;
2727 struct superblock_security_struct *sbsec;
2728 struct common_audit_data ad;
2729 u32 newsid, sid = current_sid();
2730 int rc = 0;
2731
2732 if (strcmp(name, XATTR_NAME_SELINUX))
2733 return selinux_inode_setotherxattr(dentry, name);
2734
2735 sbsec = inode->i_sb->s_security;
2736 if (!(sbsec->flags & SE_SBLABELSUPP))
2737 return -EOPNOTSUPP;
2738
2739 if (!inode_owner_or_capable(inode))
2740 return -EPERM;
2741
2742 ad.type = LSM_AUDIT_DATA_DENTRY;
2743 ad.u.dentry = dentry;
2744
2745 rc = avc_has_perm(sid, isec->sid, isec->sclass,
2746 FILE__RELABELFROM, &ad);
2747 if (rc)
2748 return rc;
2749
2750 rc = security_context_to_sid(value, size, &newsid);
2751 if (rc == -EINVAL) {
2752 if (!capable(CAP_MAC_ADMIN)) {
2753 struct audit_buffer *ab;
2754 size_t audit_size;
2755 const char *str;
2756
2757 /* We strip a nul only if it is at the end, otherwise the
2758 * context contains a nul and we should audit that */
2759 if (value) {
2760 str = value;
2761 if (str[size - 1] == '\0')
2762 audit_size = size - 1;
2763 else
2764 audit_size = size;
2765 } else {
2766 str = "";
2767 audit_size = 0;
2768 }
2769 ab = audit_log_start(current->audit_context, GFP_ATOMIC, AUDIT_SELINUX_ERR);
2770 audit_log_format(ab, "op=setxattr invalid_context=");
2771 audit_log_n_untrustedstring(ab, value, audit_size);
2772 audit_log_end(ab);
2773
2774 return rc;
2775 }
2776 rc = security_context_to_sid_force(value, size, &newsid);
2777 }
2778 if (rc)
2779 return rc;
2780
2781 rc = avc_has_perm(sid, newsid, isec->sclass,
2782 FILE__RELABELTO, &ad);
2783 if (rc)
2784 return rc;
2785
2786 rc = security_validate_transition(isec->sid, newsid, sid,
2787 isec->sclass);
2788 if (rc)
2789 return rc;
2790
2791 return avc_has_perm(newsid,
2792 sbsec->sid,
2793 SECCLASS_FILESYSTEM,
2794 FILESYSTEM__ASSOCIATE,
2795 &ad);
2796 }
2797
2798 static void selinux_inode_post_setxattr(struct dentry *dentry, const char *name,
2799 const void *value, size_t size,
2800 int flags)
2801 {
2802 struct inode *inode = dentry->d_inode;
2803 struct inode_security_struct *isec = inode->i_security;
2804 u32 newsid;
2805 int rc;
2806
2807 if (strcmp(name, XATTR_NAME_SELINUX)) {
2808 /* Not an attribute we recognize, so nothing to do. */
2809 return;
2810 }
2811
2812 rc = security_context_to_sid_force(value, size, &newsid);
2813 if (rc) {
2814 printk(KERN_ERR "SELinux: unable to map context to SID"
2815 "for (%s, %lu), rc=%d\n",
2816 inode->i_sb->s_id, inode->i_ino, -rc);
2817 return;
2818 }
2819
2820 isec->sid = newsid;
2821 return;
2822 }
2823
2824 static int selinux_inode_getxattr(struct dentry *dentry, const char *name)
2825 {
2826 const struct cred *cred = current_cred();
2827
2828 return dentry_has_perm(cred, dentry, FILE__GETATTR);
2829 }
2830
2831 static int selinux_inode_listxattr(struct dentry *dentry)
2832 {
2833 const struct cred *cred = current_cred();
2834
2835 return dentry_has_perm(cred, dentry, FILE__GETATTR);
2836 }
2837
2838 static int selinux_inode_removexattr(struct dentry *dentry, const char *name)
2839 {
2840 if (strcmp(name, XATTR_NAME_SELINUX))
2841 return selinux_inode_setotherxattr(dentry, name);
2842
2843 /* No one is allowed to remove a SELinux security label.
2844 You can change the label, but all data must be labeled. */
2845 return -EACCES;
2846 }
2847
2848 /*
2849 * Copy the inode security context value to the user.
2850 *
2851 * Permission check is handled by selinux_inode_getxattr hook.
2852 */
2853 static int selinux_inode_getsecurity(const struct inode *inode, const char *name, void **buffer, bool alloc)
2854 {
2855 u32 size;
2856 int error;
2857 char *context = NULL;
2858 struct inode_security_struct *isec = inode->i_security;
2859
2860 if (strcmp(name, XATTR_SELINUX_SUFFIX))
2861 return -EOPNOTSUPP;
2862
2863 /*
2864 * If the caller has CAP_MAC_ADMIN, then get the raw context
2865 * value even if it is not defined by current policy; otherwise,
2866 * use the in-core value under current policy.
2867 * Use the non-auditing forms of the permission checks since
2868 * getxattr may be called by unprivileged processes commonly
2869 * and lack of permission just means that we fall back to the
2870 * in-core context value, not a denial.
2871 */
2872 error = selinux_capable(current_cred(), &init_user_ns, CAP_MAC_ADMIN,
2873 SECURITY_CAP_NOAUDIT);
2874 if (!error)
2875 error = security_sid_to_context_force(isec->sid, &context,
2876 &size);
2877 else
2878 error = security_sid_to_context(isec->sid, &context, &size);
2879 if (error)
2880 return error;
2881 error = size;
2882 if (alloc) {
2883 *buffer = context;
2884 goto out_nofree;
2885 }
2886 kfree(context);
2887 out_nofree:
2888 return error;
2889 }
2890
2891 static int selinux_inode_setsecurity(struct inode *inode, const char *name,
2892 const void *value, size_t size, int flags)
2893 {
2894 struct inode_security_struct *isec = inode->i_security;
2895 u32 newsid;
2896 int rc;
2897
2898 if (strcmp(name, XATTR_SELINUX_SUFFIX))
2899 return -EOPNOTSUPP;
2900
2901 if (!value || !size)
2902 return -EACCES;
2903
2904 rc = security_context_to_sid((void *)value, size, &newsid);
2905 if (rc)
2906 return rc;
2907
2908 isec->sid = newsid;
2909 isec->initialized = 1;
2910 return 0;
2911 }
2912
2913 static int selinux_inode_listsecurity(struct inode *inode, char *buffer, size_t buffer_size)
2914 {
2915 const int len = sizeof(XATTR_NAME_SELINUX);
2916 if (buffer && len <= buffer_size)
2917 memcpy(buffer, XATTR_NAME_SELINUX, len);
2918 return len;
2919 }
2920
2921 static void selinux_inode_getsecid(const struct inode *inode, u32 *secid)
2922 {
2923 struct inode_security_struct *isec = inode->i_security;
2924 *secid = isec->sid;
2925 }
2926
2927 /* file security operations */
2928
2929 static int selinux_revalidate_file_permission(struct file *file, int mask)
2930 {
2931 const struct cred *cred = current_cred();
2932 struct inode *inode = file_inode(file);
2933
2934 /* file_mask_to_av won't add FILE__WRITE if MAY_APPEND is set */
2935 if ((file->f_flags & O_APPEND) && (mask & MAY_WRITE))
2936 mask |= MAY_APPEND;
2937
2938 return file_has_perm(cred, file,
2939 file_mask_to_av(inode->i_mode, mask));
2940 }
2941
2942 static int selinux_file_permission(struct file *file, int mask)
2943 {
2944 struct inode *inode = file_inode(file);
2945 struct file_security_struct *fsec = file->f_security;
2946 struct inode_security_struct *isec = inode->i_security;
2947 u32 sid = current_sid();
2948
2949 if (!mask)
2950 /* No permission to check. Existence test. */
2951 return 0;
2952
2953 if (sid == fsec->sid && fsec->isid == isec->sid &&
2954 fsec->pseqno == avc_policy_seqno())
2955 /* No change since file_open check. */
2956 return 0;
2957
2958 return selinux_revalidate_file_permission(file, mask);
2959 }
2960
2961 static int selinux_file_alloc_security(struct file *file)
2962 {
2963 return file_alloc_security(file);
2964 }
2965
2966 static void selinux_file_free_security(struct file *file)
2967 {
2968 file_free_security(file);
2969 }
2970
2971 static int selinux_file_ioctl(struct file *file, unsigned int cmd,
2972 unsigned long arg)
2973 {
2974 const struct cred *cred = current_cred();
2975 int error = 0;
2976
2977 switch (cmd) {
2978 case FIONREAD:
2979 /* fall through */
2980 case FIBMAP:
2981 /* fall through */
2982 case FIGETBSZ:
2983 /* fall through */
2984 case FS_IOC_GETFLAGS:
2985 /* fall through */
2986 case FS_IOC_GETVERSION:
2987 error = file_has_perm(cred, file, FILE__GETATTR);
2988 break;
2989
2990 case FS_IOC_SETFLAGS:
2991 /* fall through */
2992 case FS_IOC_SETVERSION:
2993 error = file_has_perm(cred, file, FILE__SETATTR);
2994 break;
2995
2996 /* sys_ioctl() checks */
2997 case FIONBIO:
2998 /* fall through */
2999 case FIOASYNC:
3000 error = file_has_perm(cred, file, 0);
3001 break;
3002
3003 case KDSKBENT:
3004 case KDSKBSENT:
3005 error = cred_has_capability(cred, CAP_SYS_TTY_CONFIG,
3006 SECURITY_CAP_AUDIT);
3007 break;
3008
3009 /* default case assumes that the command will go
3010 * to the file's ioctl() function.
3011 */
3012 default:
3013 error = file_has_perm(cred, file, FILE__IOCTL);
3014 }
3015 return error;
3016 }
3017
3018 static int default_noexec;
3019
3020 static int file_map_prot_check(struct file *file, unsigned long prot, int shared)
3021 {
3022 const struct cred *cred = current_cred();
3023 int rc = 0;
3024
3025 if (default_noexec &&
3026 (prot & PROT_EXEC) && (!file || (!shared && (prot & PROT_WRITE)))) {
3027 /*
3028 * We are making executable an anonymous mapping or a
3029 * private file mapping that will also be writable.
3030 * This has an additional check.
3031 */
3032 rc = cred_has_perm(cred, cred, PROCESS__EXECMEM);
3033 if (rc)
3034 goto error;
3035 }
3036
3037 if (file) {
3038 /* read access is always possible with a mapping */
3039 u32 av = FILE__READ;
3040
3041 /* write access only matters if the mapping is shared */
3042 if (shared && (prot & PROT_WRITE))
3043 av |= FILE__WRITE;
3044
3045 if (prot & PROT_EXEC)
3046 av |= FILE__EXECUTE;
3047
3048 return file_has_perm(cred, file, av);
3049 }
3050
3051 error:
3052 return rc;
3053 }
3054
3055 static int selinux_mmap_addr(unsigned long addr)
3056 {
3057 int rc = 0;
3058 u32 sid = current_sid();
3059
3060 /*
3061 * notice that we are intentionally putting the SELinux check before
3062 * the secondary cap_file_mmap check. This is such a likely attempt
3063 * at bad behaviour/exploit that we always want to get the AVC, even
3064 * if DAC would have also denied the operation.
3065 */
3066 if (addr < CONFIG_LSM_MMAP_MIN_ADDR) {
3067 rc = avc_has_perm(sid, sid, SECCLASS_MEMPROTECT,
3068 MEMPROTECT__MMAP_ZERO, NULL);
3069 if (rc)
3070 return rc;
3071 }
3072
3073 /* do DAC check on address space usage */
3074 return cap_mmap_addr(addr);
3075 }
3076
3077 static int selinux_mmap_file(struct file *file, unsigned long reqprot,
3078 unsigned long prot, unsigned long flags)
3079 {
3080 if (selinux_checkreqprot)
3081 prot = reqprot;
3082
3083 return file_map_prot_check(file, prot,
3084 (flags & MAP_TYPE) == MAP_SHARED);
3085 }
3086
3087 static int selinux_file_mprotect(struct vm_area_struct *vma,
3088 unsigned long reqprot,
3089 unsigned long prot)
3090 {
3091 const struct cred *cred = current_cred();
3092
3093 if (selinux_checkreqprot)
3094 prot = reqprot;
3095
3096 if (default_noexec &&
3097 (prot & PROT_EXEC) && !(vma->vm_flags & VM_EXEC)) {
3098 int rc = 0;
3099 if (vma->vm_start >= vma->vm_mm->start_brk &&
3100 vma->vm_end <= vma->vm_mm->brk) {
3101 rc = cred_has_perm(cred, cred, PROCESS__EXECHEAP);
3102 } else if (!vma->vm_file &&
3103 vma->vm_start <= vma->vm_mm->start_stack &&
3104 vma->vm_end >= vma->vm_mm->start_stack) {
3105 rc = current_has_perm(current, PROCESS__EXECSTACK);
3106 } else if (vma->vm_file && vma->anon_vma) {
3107 /*
3108 * We are making executable a file mapping that has
3109 * had some COW done. Since pages might have been
3110 * written, check ability to execute the possibly
3111 * modified content. This typically should only
3112 * occur for text relocations.
3113 */
3114 rc = file_has_perm(cred, vma->vm_file, FILE__EXECMOD);
3115 }
3116 if (rc)
3117 return rc;
3118 }
3119
3120 return file_map_prot_check(vma->vm_file, prot, vma->vm_flags&VM_SHARED);
3121 }
3122
3123 static int selinux_file_lock(struct file *file, unsigned int cmd)
3124 {
3125 const struct cred *cred = current_cred();
3126
3127 return file_has_perm(cred, file, FILE__LOCK);
3128 }
3129
3130 static int selinux_file_fcntl(struct file *file, unsigned int cmd,
3131 unsigned long arg)
3132 {
3133 const struct cred *cred = current_cred();
3134 int err = 0;
3135
3136 switch (cmd) {
3137 case F_SETFL:
3138 if (!file->f_path.dentry || !file->f_path.dentry->d_inode) {
3139 err = -EINVAL;
3140 break;
3141 }
3142
3143 if ((file->f_flags & O_APPEND) && !(arg & O_APPEND)) {
3144 err = file_has_perm(cred, file, FILE__WRITE);
3145 break;
3146 }
3147 /* fall through */
3148 case F_SETOWN:
3149 case F_SETSIG:
3150 case F_GETFL:
3151 case F_GETOWN:
3152 case F_GETSIG:
3153 case F_GETOWNER_UIDS:
3154 /* Just check FD__USE permission */
3155 err = file_has_perm(cred, file, 0);
3156 break;
3157 case F_GETLK:
3158 case F_SETLK:
3159 case F_SETLKW:
3160 #if BITS_PER_LONG == 32
3161 case F_GETLK64:
3162 case F_SETLK64:
3163 case F_SETLKW64:
3164 #endif
3165 if (!file->f_path.dentry || !file->f_path.dentry->d_inode) {
3166 err = -EINVAL;
3167 break;
3168 }
3169 err = file_has_perm(cred, file, FILE__LOCK);
3170 break;
3171 }
3172
3173 return err;
3174 }
3175
3176 static int selinux_file_set_fowner(struct file *file)
3177 {
3178 struct file_security_struct *fsec;
3179
3180 fsec = file->f_security;
3181 fsec->fown_sid = current_sid();
3182
3183 return 0;
3184 }
3185
3186 static int selinux_file_send_sigiotask(struct task_struct *tsk,
3187 struct fown_struct *fown, int signum)
3188 {
3189 struct file *file;
3190 u32 sid = task_sid(tsk);
3191 u32 perm;
3192 struct file_security_struct *fsec;
3193
3194 /* struct fown_struct is never outside the context of a struct file */
3195 file = container_of(fown, struct file, f_owner);
3196
3197 fsec = file->f_security;
3198
3199 if (!signum)
3200 perm = signal_to_av(SIGIO); /* as per send_sigio_to_task */
3201 else
3202 perm = signal_to_av(signum);
3203
3204 return avc_has_perm(fsec->fown_sid, sid,
3205 SECCLASS_PROCESS, perm, NULL);
3206 }
3207
3208 static int selinux_file_receive(struct file *file)
3209 {
3210 const struct cred *cred = current_cred();
3211
3212 return file_has_perm(cred, file, file_to_av(file));
3213 }
3214
3215 static int selinux_file_open(struct file *file, const struct cred *cred)
3216 {
3217 struct file_security_struct *fsec;
3218 struct inode_security_struct *isec;
3219
3220 fsec = file->f_security;
3221 isec = file_inode(file)->i_security;
3222 /*
3223 * Save inode label and policy sequence number
3224 * at open-time so that selinux_file_permission
3225 * can determine whether revalidation is necessary.
3226 * Task label is already saved in the file security
3227 * struct as its SID.
3228 */
3229 fsec->isid = isec->sid;
3230 fsec->pseqno = avc_policy_seqno();
3231 /*
3232 * Since the inode label or policy seqno may have changed
3233 * between the selinux_inode_permission check and the saving
3234 * of state above, recheck that access is still permitted.
3235 * Otherwise, access might never be revalidated against the
3236 * new inode label or new policy.
3237 * This check is not redundant - do not remove.
3238 */
3239 return path_has_perm(cred, &file->f_path, open_file_to_av(file));
3240 }
3241
3242 /* task security operations */
3243
3244 static int selinux_task_create(unsigned long clone_flags)
3245 {
3246 return current_has_perm(current, PROCESS__FORK);
3247 }
3248
3249 /*
3250 * allocate the SELinux part of blank credentials
3251 */
3252 static int selinux_cred_alloc_blank(struct cred *cred, gfp_t gfp)
3253 {
3254 struct task_security_struct *tsec;
3255
3256 tsec = kzalloc(sizeof(struct task_security_struct), gfp);
3257 if (!tsec)
3258 return -ENOMEM;
3259
3260 cred->security = tsec;
3261 return 0;
3262 }
3263
3264 /*
3265 * detach and free the LSM part of a set of credentials
3266 */
3267 static void selinux_cred_free(struct cred *cred)
3268 {
3269 struct task_security_struct *tsec = cred->security;
3270
3271 /*
3272 * cred->security == NULL if security_cred_alloc_blank() or
3273 * security_prepare_creds() returned an error.
3274 */
3275 BUG_ON(cred->security && (unsigned long) cred->security < PAGE_SIZE);
3276 cred->security = (void *) 0x7UL;
3277 kfree(tsec);
3278 }
3279
3280 /*
3281 * prepare a new set of credentials for modification
3282 */
3283 static int selinux_cred_prepare(struct cred *new, const struct cred *old,
3284 gfp_t gfp)
3285 {
3286 const struct task_security_struct *old_tsec;
3287 struct task_security_struct *tsec;
3288
3289 old_tsec = old->security;
3290
3291 tsec = kmemdup(old_tsec, sizeof(struct task_security_struct), gfp);
3292 if (!tsec)
3293 return -ENOMEM;
3294
3295 new->security = tsec;
3296 return 0;
3297 }
3298
3299 /*
3300 * transfer the SELinux data to a blank set of creds
3301 */
3302 static void selinux_cred_transfer(struct cred *new, const struct cred *old)
3303 {
3304 const struct task_security_struct *old_tsec = old->security;
3305 struct task_security_struct *tsec = new->security;
3306
3307 *tsec = *old_tsec;
3308 }
3309
3310 /*
3311 * set the security data for a kernel service
3312 * - all the creation contexts are set to unlabelled
3313 */
3314 static int selinux_kernel_act_as(struct cred *new, u32 secid)
3315 {
3316 struct task_security_struct *tsec = new->security;
3317 u32 sid = current_sid();
3318 int ret;
3319
3320 ret = avc_has_perm(sid, secid,
3321 SECCLASS_KERNEL_SERVICE,
3322 KERNEL_SERVICE__USE_AS_OVERRIDE,
3323 NULL);
3324 if (ret == 0) {
3325 tsec->sid = secid;
3326 tsec->create_sid = 0;
3327 tsec->keycreate_sid = 0;
3328 tsec->sockcreate_sid = 0;
3329 }
3330 return ret;
3331 }
3332
3333 /*
3334 * set the file creation context in a security record to the same as the
3335 * objective context of the specified inode
3336 */
3337 static int selinux_kernel_create_files_as(struct cred *new, struct inode *inode)
3338 {
3339 struct inode_security_struct *isec = inode->i_security;
3340 struct task_security_struct *tsec = new->security;
3341 u32 sid = current_sid();
3342 int ret;
3343
3344 ret = avc_has_perm(sid, isec->sid,
3345 SECCLASS_KERNEL_SERVICE,
3346 KERNEL_SERVICE__CREATE_FILES_AS,
3347 NULL);
3348
3349 if (ret == 0)
3350 tsec->create_sid = isec->sid;
3351 return ret;
3352 }
3353
3354 static int selinux_kernel_module_request(char *kmod_name)
3355 {
3356 u32 sid;
3357 struct common_audit_data ad;
3358
3359 sid = task_sid(current);
3360
3361 ad.type = LSM_AUDIT_DATA_KMOD;
3362 ad.u.kmod_name = kmod_name;
3363
3364 return avc_has_perm(sid, SECINITSID_KERNEL, SECCLASS_SYSTEM,
3365 SYSTEM__MODULE_REQUEST, &ad);
3366 }
3367
3368 static int selinux_task_setpgid(struct task_struct *p, pid_t pgid)
3369 {
3370 return current_has_perm(p, PROCESS__SETPGID);
3371 }
3372
3373 static int selinux_task_getpgid(struct task_struct *p)
3374 {
3375 return current_has_perm(p, PROCESS__GETPGID);
3376 }
3377
3378 static int selinux_task_getsid(struct task_struct *p)
3379 {
3380 return current_has_perm(p, PROCESS__GETSESSION);
3381 }
3382
3383 static void selinux_task_getsecid(struct task_struct *p, u32 *secid)
3384 {
3385 *secid = task_sid(p);
3386 }
3387
3388 static int selinux_task_setnice(struct task_struct *p, int nice)
3389 {
3390 int rc;
3391
3392 rc = cap_task_setnice(p, nice);
3393 if (rc)
3394 return rc;
3395
3396 return current_has_perm(p, PROCESS__SETSCHED);
3397 }
3398
3399 static int selinux_task_setioprio(struct task_struct *p, int ioprio)
3400 {
3401 int rc;
3402
3403 rc = cap_task_setioprio(p, ioprio);
3404 if (rc)
3405 return rc;
3406
3407 return current_has_perm(p, PROCESS__SETSCHED);
3408 }
3409
3410 static int selinux_task_getioprio(struct task_struct *p)
3411 {
3412 return current_has_perm(p, PROCESS__GETSCHED);
3413 }
3414
3415 static int selinux_task_setrlimit(struct task_struct *p, unsigned int resource,
3416 struct rlimit *new_rlim)
3417 {
3418 struct rlimit *old_rlim = p->signal->rlim + resource;
3419
3420 /* Control the ability to change the hard limit (whether
3421 lowering or raising it), so that the hard limit can
3422 later be used as a safe reset point for the soft limit
3423 upon context transitions. See selinux_bprm_committing_creds. */
3424 if (old_rlim->rlim_max != new_rlim->rlim_max)
3425 return current_has_perm(p, PROCESS__SETRLIMIT);
3426
3427 return 0;
3428 }
3429
3430 static int selinux_task_setscheduler(struct task_struct *p)
3431 {
3432 int rc;
3433
3434 rc = cap_task_setscheduler(p);
3435 if (rc)
3436 return rc;
3437
3438 return current_has_perm(p, PROCESS__SETSCHED);
3439 }
3440
3441 static int selinux_task_getscheduler(struct task_struct *p)
3442 {
3443 return current_has_perm(p, PROCESS__GETSCHED);
3444 }
3445
3446 static int selinux_task_movememory(struct task_struct *p)
3447 {
3448 return current_has_perm(p, PROCESS__SETSCHED);
3449 }
3450
3451 static int selinux_task_kill(struct task_struct *p, struct siginfo *info,
3452 int sig, u32 secid)
3453 {
3454 u32 perm;
3455 int rc;
3456
3457 if (!sig)
3458 perm = PROCESS__SIGNULL; /* null signal; existence test */
3459 else
3460 perm = signal_to_av(sig);
3461 if (secid)
3462 rc = avc_has_perm(secid, task_sid(p),
3463 SECCLASS_PROCESS, perm, NULL);
3464 else
3465 rc = current_has_perm(p, perm);
3466 return rc;
3467 }
3468
3469 static int selinux_task_wait(struct task_struct *p)
3470 {
3471 return task_has_perm(p, current, PROCESS__SIGCHLD);
3472 }
3473
3474 static void selinux_task_to_inode(struct task_struct *p,
3475 struct inode *inode)
3476 {
3477 struct inode_security_struct *isec = inode->i_security;
3478 u32 sid = task_sid(p);
3479
3480 isec->sid = sid;
3481 isec->initialized = 1;
3482 }
3483
3484 /* Returns error only if unable to parse addresses */
3485 static int selinux_parse_skb_ipv4(struct sk_buff *skb,
3486 struct common_audit_data *ad, u8 *proto)
3487 {
3488 int offset, ihlen, ret = -EINVAL;
3489 struct iphdr _iph, *ih;
3490
3491 offset = skb_network_offset(skb);
3492 ih = skb_header_pointer(skb, offset, sizeof(_iph), &_iph);
3493 if (ih == NULL)
3494 goto out;
3495
3496 ihlen = ih->ihl * 4;
3497 if (ihlen < sizeof(_iph))
3498 goto out;
3499
3500 ad->u.net->v4info.saddr = ih->saddr;
3501 ad->u.net->v4info.daddr = ih->daddr;
3502 ret = 0;
3503
3504 if (proto)
3505 *proto = ih->protocol;
3506
3507 switch (ih->protocol) {
3508 case IPPROTO_TCP: {
3509 struct tcphdr _tcph, *th;
3510
3511 if (ntohs(ih->frag_off) & IP_OFFSET)
3512 break;
3513
3514 offset += ihlen;
3515 th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph);
3516 if (th == NULL)
3517 break;
3518
3519 ad->u.net->sport = th->source;
3520 ad->u.net->dport = th->dest;
3521 break;
3522 }
3523
3524 case IPPROTO_UDP: {
3525 struct udphdr _udph, *uh;
3526
3527 if (ntohs(ih->frag_off) & IP_OFFSET)
3528 break;
3529
3530 offset += ihlen;
3531 uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph);
3532 if (uh == NULL)
3533 break;
3534
3535 ad->u.net->sport = uh->source;
3536 ad->u.net->dport = uh->dest;
3537 break;
3538 }
3539
3540 case IPPROTO_DCCP: {
3541 struct dccp_hdr _dccph, *dh;
3542
3543 if (ntohs(ih->frag_off) & IP_OFFSET)
3544 break;
3545
3546 offset += ihlen;
3547 dh = skb_header_pointer(skb, offset, sizeof(_dccph), &_dccph);
3548 if (dh == NULL)
3549 break;
3550
3551 ad->u.net->sport = dh->dccph_sport;
3552 ad->u.net->dport = dh->dccph_dport;
3553 break;
3554 }
3555
3556 default:
3557 break;
3558 }
3559 out:
3560 return ret;
3561 }
3562
3563 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
3564
3565 /* Returns error only if unable to parse addresses */
3566 static int selinux_parse_skb_ipv6(struct sk_buff *skb,
3567 struct common_audit_data *ad, u8 *proto)
3568 {
3569 u8 nexthdr;
3570 int ret = -EINVAL, offset;
3571 struct ipv6hdr _ipv6h, *ip6;
3572 __be16 frag_off;
3573
3574 offset = skb_network_offset(skb);
3575 ip6 = skb_header_pointer(skb, offset, sizeof(_ipv6h), &_ipv6h);
3576 if (ip6 == NULL)
3577 goto out;
3578
3579 ad->u.net->v6info.saddr = ip6->saddr;
3580 ad->u.net->v6info.daddr = ip6->daddr;
3581 ret = 0;
3582
3583 nexthdr = ip6->nexthdr;
3584 offset += sizeof(_ipv6h);
3585 offset = ipv6_skip_exthdr(skb, offset, &nexthdr, &frag_off);
3586 if (offset < 0)
3587 goto out;
3588
3589 if (proto)
3590 *proto = nexthdr;
3591
3592 switch (nexthdr) {
3593 case IPPROTO_TCP: {
3594 struct tcphdr _tcph, *th;
3595
3596 th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph);
3597 if (th == NULL)
3598 break;
3599
3600 ad->u.net->sport = th->source;
3601 ad->u.net->dport = th->dest;
3602 break;
3603 }
3604
3605 case IPPROTO_UDP: {
3606 struct udphdr _udph, *uh;
3607
3608 uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph);
3609 if (uh == NULL)
3610 break;
3611
3612 ad->u.net->sport = uh->source;
3613 ad->u.net->dport = uh->dest;
3614 break;
3615 }
3616
3617 case IPPROTO_DCCP: {
3618 struct dccp_hdr _dccph, *dh;
3619
3620 dh = skb_header_pointer(skb, offset, sizeof(_dccph), &_dccph);
3621 if (dh == NULL)
3622 break;
3623
3624 ad->u.net->sport = dh->dccph_sport;
3625 ad->u.net->dport = dh->dccph_dport;
3626 break;
3627 }
3628
3629 /* includes fragments */
3630 default:
3631 break;
3632 }
3633 out:
3634 return ret;
3635 }
3636
3637 #endif /* IPV6 */
3638
3639 static int selinux_parse_skb(struct sk_buff *skb, struct common_audit_data *ad,
3640 char **_addrp, int src, u8 *proto)
3641 {
3642 char *addrp;
3643 int ret;
3644
3645 switch (ad->u.net->family) {
3646 case PF_INET:
3647 ret = selinux_parse_skb_ipv4(skb, ad, proto);
3648 if (ret)
3649 goto parse_error;
3650 addrp = (char *)(src ? &ad->u.net->v4info.saddr :
3651 &ad->u.net->v4info.daddr);
3652 goto okay;
3653
3654 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
3655 case PF_INET6:
3656 ret = selinux_parse_skb_ipv6(skb, ad, proto);
3657 if (ret)
3658 goto parse_error;
3659 addrp = (char *)(src ? &ad->u.net->v6info.saddr :
3660 &ad->u.net->v6info.daddr);
3661 goto okay;
3662 #endif /* IPV6 */
3663 default:
3664 addrp = NULL;
3665 goto okay;
3666 }
3667
3668 parse_error:
3669 printk(KERN_WARNING
3670 "SELinux: failure in selinux_parse_skb(),"
3671 " unable to parse packet\n");
3672 return ret;
3673
3674 okay:
3675 if (_addrp)
3676 *_addrp = addrp;
3677 return 0;
3678 }
3679
3680 /**
3681 * selinux_skb_peerlbl_sid - Determine the peer label of a packet
3682 * @skb: the packet
3683 * @family: protocol family
3684 * @sid: the packet's peer label SID
3685 *
3686 * Description:
3687 * Check the various different forms of network peer labeling and determine
3688 * the peer label/SID for the packet; most of the magic actually occurs in
3689 * the security server function security_net_peersid_cmp(). The function
3690 * returns zero if the value in @sid is valid (although it may be SECSID_NULL)
3691 * or -EACCES if @sid is invalid due to inconsistencies with the different
3692 * peer labels.
3693 *
3694 */
3695 static int selinux_skb_peerlbl_sid(struct sk_buff *skb, u16 family, u32 *sid)
3696 {
3697 int err;
3698 u32 xfrm_sid;
3699 u32 nlbl_sid;
3700 u32 nlbl_type;
3701
3702 selinux_skb_xfrm_sid(skb, &xfrm_sid);
3703 selinux_netlbl_skbuff_getsid(skb, family, &nlbl_type, &nlbl_sid);
3704
3705 err = security_net_peersid_resolve(nlbl_sid, nlbl_type, xfrm_sid, sid);
3706 if (unlikely(err)) {
3707 printk(KERN_WARNING
3708 "SELinux: failure in selinux_skb_peerlbl_sid(),"
3709 " unable to determine packet's peer label\n");
3710 return -EACCES;
3711 }
3712
3713 return 0;
3714 }
3715
3716 /* socket security operations */
3717
3718 static int socket_sockcreate_sid(const struct task_security_struct *tsec,
3719 u16 secclass, u32 *socksid)
3720 {
3721 if (tsec->sockcreate_sid > SECSID_NULL) {
3722 *socksid = tsec->sockcreate_sid;
3723 return 0;
3724 }
3725
3726 return security_transition_sid(tsec->sid, tsec->sid, secclass, NULL,
3727 socksid);
3728 }
3729
3730 static int sock_has_perm(struct task_struct *task, struct sock *sk, u32 perms)
3731 {
3732 struct sk_security_struct *sksec = sk->sk_security;
3733 struct common_audit_data ad;
3734 struct lsm_network_audit net = {0,};
3735 u32 tsid = task_sid(task);
3736
3737 if (sksec->sid == SECINITSID_KERNEL)
3738 return 0;
3739
3740 ad.type = LSM_AUDIT_DATA_NET;
3741 ad.u.net = &net;
3742 ad.u.net->sk = sk;
3743
3744 return avc_has_perm(tsid, sksec->sid, sksec->sclass, perms, &ad);
3745 }
3746
3747 static int selinux_socket_create(int family, int type,
3748 int protocol, int kern)
3749 {
3750 const struct task_security_struct *tsec = current_security();
3751 u32 newsid;
3752 u16 secclass;
3753 int rc;
3754
3755 if (kern)
3756 return 0;
3757
3758 secclass = socket_type_to_security_class(family, type, protocol);
3759 rc = socket_sockcreate_sid(tsec, secclass, &newsid);
3760 if (rc)
3761 return rc;
3762
3763 return avc_has_perm(tsec->sid, newsid, secclass, SOCKET__CREATE, NULL);
3764 }
3765
3766 static int selinux_socket_post_create(struct socket *sock, int family,
3767 int type, int protocol, int kern)
3768 {
3769 const struct task_security_struct *tsec = current_security();
3770 struct inode_security_struct *isec = SOCK_INODE(sock)->i_security;
3771 struct sk_security_struct *sksec;
3772 int err = 0;
3773
3774 isec->sclass = socket_type_to_security_class(family, type, protocol);
3775
3776 if (kern)
3777 isec->sid = SECINITSID_KERNEL;
3778 else {
3779 err = socket_sockcreate_sid(tsec, isec->sclass, &(isec->sid));
3780 if (err)
3781 return err;
3782 }
3783
3784 isec->initialized = 1;
3785
3786 if (sock->sk) {
3787 sksec = sock->sk->sk_security;
3788 sksec->sid = isec->sid;
3789 sksec->sclass = isec->sclass;
3790 err = selinux_netlbl_socket_post_create(sock->sk, family);
3791 }
3792
3793 return err;
3794 }
3795
3796 /* Range of port numbers used to automatically bind.
3797 Need to determine whether we should perform a name_bind
3798 permission check between the socket and the port number. */
3799
3800 static int selinux_socket_bind(struct socket *sock, struct sockaddr *address, int addrlen)
3801 {
3802 struct sock *sk = sock->sk;
3803 u16 family;
3804 int err;
3805
3806 err = sock_has_perm(current, sk, SOCKET__BIND);
3807 if (err)
3808 goto out;
3809
3810 /*
3811 * If PF_INET or PF_INET6, check name_bind permission for the port.
3812 * Multiple address binding for SCTP is not supported yet: we just
3813 * check the first address now.
3814 */
3815 family = sk->sk_family;
3816 if (family == PF_INET || family == PF_INET6) {
3817 char *addrp;
3818 struct sk_security_struct *sksec = sk->sk_security;
3819 struct common_audit_data ad;
3820 struct lsm_network_audit net = {0,};
3821 struct sockaddr_in *addr4 = NULL;
3822 struct sockaddr_in6 *addr6 = NULL;
3823 unsigned short snum;
3824 u32 sid, node_perm;
3825
3826 if (family == PF_INET) {
3827 addr4 = (struct sockaddr_in *)address;
3828 snum = ntohs(addr4->sin_port);
3829 addrp = (char *)&addr4->sin_addr.s_addr;
3830 } else {
3831 addr6 = (struct sockaddr_in6 *)address;
3832 snum = ntohs(addr6->sin6_port);
3833 addrp = (char *)&addr6->sin6_addr.s6_addr;
3834 }
3835
3836 if (snum) {
3837 int low, high;
3838
3839 inet_get_local_port_range(&low, &high);
3840
3841 if (snum < max(PROT_SOCK, low) || snum > high) {
3842 err = sel_netport_sid(sk->sk_protocol,
3843 snum, &sid);
3844 if (err)
3845 goto out;
3846 ad.type = LSM_AUDIT_DATA_NET;
3847 ad.u.net = &net;
3848 ad.u.net->sport = htons(snum);
3849 ad.u.net->family = family;
3850 err = avc_has_perm(sksec->sid, sid,
3851 sksec->sclass,
3852 SOCKET__NAME_BIND, &ad);
3853 if (err)
3854 goto out;
3855 }
3856 }
3857
3858 switch (sksec->sclass) {
3859 case SECCLASS_TCP_SOCKET:
3860 node_perm = TCP_SOCKET__NODE_BIND;
3861 break;
3862
3863 case SECCLASS_UDP_SOCKET:
3864 node_perm = UDP_SOCKET__NODE_BIND;
3865 break;
3866
3867 case SECCLASS_DCCP_SOCKET:
3868 node_perm = DCCP_SOCKET__NODE_BIND;
3869 break;
3870
3871 default:
3872 node_perm = RAWIP_SOCKET__NODE_BIND;
3873 break;
3874 }
3875
3876 err = sel_netnode_sid(addrp, family, &sid);
3877 if (err)
3878 goto out;
3879
3880 ad.type = LSM_AUDIT_DATA_NET;
3881 ad.u.net = &net;
3882 ad.u.net->sport = htons(snum);
3883 ad.u.net->family = family;
3884
3885 if (family == PF_INET)
3886 ad.u.net->v4info.saddr = addr4->sin_addr.s_addr;
3887 else
3888 ad.u.net->v6info.saddr = addr6->sin6_addr;
3889
3890 err = avc_has_perm(sksec->sid, sid,
3891 sksec->sclass, node_perm, &ad);
3892 if (err)
3893 goto out;
3894 }
3895 out:
3896 return err;
3897 }
3898
3899 static int selinux_socket_connect(struct socket *sock, struct sockaddr *address, int addrlen)
3900 {
3901 struct sock *sk = sock->sk;
3902 struct sk_security_struct *sksec = sk->sk_security;
3903 int err;
3904
3905 err = sock_has_perm(current, sk, SOCKET__CONNECT);
3906 if (err)
3907 return err;
3908
3909 /*
3910 * If a TCP or DCCP socket, check name_connect permission for the port.
3911 */
3912 if (sksec->sclass == SECCLASS_TCP_SOCKET ||
3913 sksec->sclass == SECCLASS_DCCP_SOCKET) {
3914 struct common_audit_data ad;
3915 struct lsm_network_audit net = {0,};
3916 struct sockaddr_in *addr4 = NULL;
3917 struct sockaddr_in6 *addr6 = NULL;
3918 unsigned short snum;
3919 u32 sid, perm;
3920
3921 if (sk->sk_family == PF_INET) {
3922 addr4 = (struct sockaddr_in *)address;
3923 if (addrlen < sizeof(struct sockaddr_in))
3924 return -EINVAL;
3925 snum = ntohs(addr4->sin_port);
3926 } else {
3927 addr6 = (struct sockaddr_in6 *)address;
3928 if (addrlen < SIN6_LEN_RFC2133)
3929 return -EINVAL;
3930 snum = ntohs(addr6->sin6_port);
3931 }
3932
3933 err = sel_netport_sid(sk->sk_protocol, snum, &sid);
3934 if (err)
3935 goto out;
3936
3937 perm = (sksec->sclass == SECCLASS_TCP_SOCKET) ?
3938 TCP_SOCKET__NAME_CONNECT : DCCP_SOCKET__NAME_CONNECT;
3939
3940 ad.type = LSM_AUDIT_DATA_NET;
3941 ad.u.net = &net;
3942 ad.u.net->dport = htons(snum);
3943 ad.u.net->family = sk->sk_family;
3944 err = avc_has_perm(sksec->sid, sid, sksec->sclass, perm, &ad);
3945 if (err)
3946 goto out;
3947 }
3948
3949 err = selinux_netlbl_socket_connect(sk, address);
3950
3951 out:
3952 return err;
3953 }
3954
3955 static int selinux_socket_listen(struct socket *sock, int backlog)
3956 {
3957 return sock_has_perm(current, sock->sk, SOCKET__LISTEN);
3958 }
3959
3960 static int selinux_socket_accept(struct socket *sock, struct socket *newsock)
3961 {
3962 int err;
3963 struct inode_security_struct *isec;
3964 struct inode_security_struct *newisec;
3965
3966 err = sock_has_perm(current, sock->sk, SOCKET__ACCEPT);
3967 if (err)
3968 return err;
3969
3970 newisec = SOCK_INODE(newsock)->i_security;
3971
3972 isec = SOCK_INODE(sock)->i_security;
3973 newisec->sclass = isec->sclass;
3974 newisec->sid = isec->sid;
3975 newisec->initialized = 1;
3976
3977 return 0;
3978 }
3979
3980 static int selinux_socket_sendmsg(struct socket *sock, struct msghdr *msg,
3981 int size)
3982 {
3983 return sock_has_perm(current, sock->sk, SOCKET__WRITE);
3984 }
3985
3986 static int selinux_socket_recvmsg(struct socket *sock, struct msghdr *msg,
3987 int size, int flags)
3988 {
3989 return sock_has_perm(current, sock->sk, SOCKET__READ);
3990 }
3991
3992 static int selinux_socket_getsockname(struct socket *sock)
3993 {
3994 return sock_has_perm(current, sock->sk, SOCKET__GETATTR);
3995 }
3996
3997 static int selinux_socket_getpeername(struct socket *sock)
3998 {
3999 return sock_has_perm(current, sock->sk, SOCKET__GETATTR);
4000 }
4001
4002 static int selinux_socket_setsockopt(struct socket *sock, int level, int optname)
4003 {
4004 int err;
4005
4006 err = sock_has_perm(current, sock->sk, SOCKET__SETOPT);
4007 if (err)
4008 return err;
4009
4010 return selinux_netlbl_socket_setsockopt(sock, level, optname);
4011 }
4012
4013 static int selinux_socket_getsockopt(struct socket *sock, int level,
4014 int optname)
4015 {
4016 return sock_has_perm(current, sock->sk, SOCKET__GETOPT);
4017 }
4018
4019 static int selinux_socket_shutdown(struct socket *sock, int how)
4020 {
4021 return sock_has_perm(current, sock->sk, SOCKET__SHUTDOWN);
4022 }
4023
4024 static int selinux_socket_unix_stream_connect(struct sock *sock,
4025 struct sock *other,
4026 struct sock *newsk)
4027 {
4028 struct sk_security_struct *sksec_sock = sock->sk_security;
4029 struct sk_security_struct *sksec_other = other->sk_security;
4030 struct sk_security_struct *sksec_new = newsk->sk_security;
4031 struct common_audit_data ad;
4032 struct lsm_network_audit net = {0,};
4033 int err;
4034
4035 ad.type = LSM_AUDIT_DATA_NET;
4036 ad.u.net = &net;
4037 ad.u.net->sk = other;
4038
4039 err = avc_has_perm(sksec_sock->sid, sksec_other->sid,
4040 sksec_other->sclass,
4041 UNIX_STREAM_SOCKET__CONNECTTO, &ad);
4042 if (err)
4043 return err;
4044
4045 /* server child socket */
4046 sksec_new->peer_sid = sksec_sock->sid;
4047 err = security_sid_mls_copy(sksec_other->sid, sksec_sock->sid,
4048 &sksec_new->sid);
4049 if (err)
4050 return err;
4051
4052 /* connecting socket */
4053 sksec_sock->peer_sid = sksec_new->sid;
4054
4055 return 0;
4056 }
4057
4058 static int selinux_socket_unix_may_send(struct socket *sock,
4059 struct socket *other)
4060 {
4061 struct sk_security_struct *ssec = sock->sk->sk_security;
4062 struct sk_security_struct *osec = other->sk->sk_security;
4063 struct common_audit_data ad;
4064 struct lsm_network_audit net = {0,};
4065
4066 ad.type = LSM_AUDIT_DATA_NET;
4067 ad.u.net = &net;
4068 ad.u.net->sk = other->sk;
4069
4070 return avc_has_perm(ssec->sid, osec->sid, osec->sclass, SOCKET__SENDTO,
4071 &ad);
4072 }
4073
4074 static int selinux_inet_sys_rcv_skb(int ifindex, char *addrp, u16 family,
4075 u32 peer_sid,
4076 struct common_audit_data *ad)
4077 {
4078 int err;
4079 u32 if_sid;
4080 u32 node_sid;
4081
4082 err = sel_netif_sid(ifindex, &if_sid);
4083 if (err)
4084 return err;
4085 err = avc_has_perm(peer_sid, if_sid,
4086 SECCLASS_NETIF, NETIF__INGRESS, ad);
4087 if (err)
4088 return err;
4089
4090 err = sel_netnode_sid(addrp, family, &node_sid);
4091 if (err)
4092 return err;
4093 return avc_has_perm(peer_sid, node_sid,
4094 SECCLASS_NODE, NODE__RECVFROM, ad);
4095 }
4096
4097 static int selinux_sock_rcv_skb_compat(struct sock *sk, struct sk_buff *skb,
4098 u16 family)
4099 {
4100 int err = 0;
4101 struct sk_security_struct *sksec = sk->sk_security;
4102 u32 sk_sid = sksec->sid;
4103 struct common_audit_data ad;
4104 struct lsm_network_audit net = {0,};
4105 char *addrp;
4106
4107 ad.type = LSM_AUDIT_DATA_NET;
4108 ad.u.net = &net;
4109 ad.u.net->netif = skb->skb_iif;
4110 ad.u.net->family = family;
4111 err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL);
4112 if (err)
4113 return err;
4114
4115 if (selinux_secmark_enabled()) {
4116 err = avc_has_perm(sk_sid, skb->secmark, SECCLASS_PACKET,
4117 PACKET__RECV, &ad);
4118 if (err)
4119 return err;
4120 }
4121
4122 err = selinux_netlbl_sock_rcv_skb(sksec, skb, family, &ad);
4123 if (err)
4124 return err;
4125 err = selinux_xfrm_sock_rcv_skb(sksec->sid, skb, &ad);
4126
4127 return err;
4128 }
4129
4130 static int selinux_socket_sock_rcv_skb(struct sock *sk, struct sk_buff *skb)
4131 {
4132 int err;
4133 struct sk_security_struct *sksec = sk->sk_security;
4134 u16 family = sk->sk_family;
4135 u32 sk_sid = sksec->sid;
4136 struct common_audit_data ad;
4137 struct lsm_network_audit net = {0,};
4138 char *addrp;
4139 u8 secmark_active;
4140 u8 peerlbl_active;
4141
4142 if (family != PF_INET && family != PF_INET6)
4143 return 0;
4144
4145 /* Handle mapped IPv4 packets arriving via IPv6 sockets */
4146 if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
4147 family = PF_INET;
4148
4149 /* If any sort of compatibility mode is enabled then handoff processing
4150 * to the selinux_sock_rcv_skb_compat() function to deal with the
4151 * special handling. We do this in an attempt to keep this function
4152 * as fast and as clean as possible. */
4153 if (!selinux_policycap_netpeer)
4154 return selinux_sock_rcv_skb_compat(sk, skb, family);
4155
4156 secmark_active = selinux_secmark_enabled();
4157 peerlbl_active = netlbl_enabled() || selinux_xfrm_enabled();
4158 if (!secmark_active && !peerlbl_active)
4159 return 0;
4160
4161 ad.type = LSM_AUDIT_DATA_NET;
4162 ad.u.net = &net;
4163 ad.u.net->netif = skb->skb_iif;
4164 ad.u.net->family = family;
4165 err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL);
4166 if (err)
4167 return err;
4168
4169 if (peerlbl_active) {
4170 u32 peer_sid;
4171
4172 err = selinux_skb_peerlbl_sid(skb, family, &peer_sid);
4173 if (err)
4174 return err;
4175 err = selinux_inet_sys_rcv_skb(skb->skb_iif, addrp, family,
4176 peer_sid, &ad);
4177 if (err) {
4178 selinux_netlbl_err(skb, err, 0);
4179 return err;
4180 }
4181 err = avc_has_perm(sk_sid, peer_sid, SECCLASS_PEER,
4182 PEER__RECV, &ad);
4183 if (err)
4184 selinux_netlbl_err(skb, err, 0);
4185 }
4186
4187 if (secmark_active) {
4188 err = avc_has_perm(sk_sid, skb->secmark, SECCLASS_PACKET,
4189 PACKET__RECV, &ad);
4190 if (err)
4191 return err;
4192 }
4193
4194 return err;
4195 }
4196
4197 static int selinux_socket_getpeersec_stream(struct socket *sock, char __user *optval,
4198 int __user *optlen, unsigned len)
4199 {
4200 int err = 0;
4201 char *scontext;
4202 u32 scontext_len;
4203 struct sk_security_struct *sksec = sock->sk->sk_security;
4204 u32 peer_sid = SECSID_NULL;
4205
4206 if (sksec->sclass == SECCLASS_UNIX_STREAM_SOCKET ||
4207 sksec->sclass == SECCLASS_TCP_SOCKET)
4208 peer_sid = sksec->peer_sid;
4209 if (peer_sid == SECSID_NULL)
4210 return -ENOPROTOOPT;
4211
4212 err = security_sid_to_context(peer_sid, &scontext, &scontext_len);
4213 if (err)
4214 return err;
4215
4216 if (scontext_len > len) {
4217 err = -ERANGE;
4218 goto out_len;
4219 }
4220
4221 if (copy_to_user(optval, scontext, scontext_len))
4222 err = -EFAULT;
4223
4224 out_len:
4225 if (put_user(scontext_len, optlen))
4226 err = -EFAULT;
4227 kfree(scontext);
4228 return err;
4229 }
4230
4231 static int selinux_socket_getpeersec_dgram(struct socket *sock, struct sk_buff *skb, u32 *secid)
4232 {
4233 u32 peer_secid = SECSID_NULL;
4234 u16 family;
4235
4236 if (skb && skb->protocol == htons(ETH_P_IP))
4237 family = PF_INET;
4238 else if (skb && skb->protocol == htons(ETH_P_IPV6))
4239 family = PF_INET6;
4240 else if (sock)
4241 family = sock->sk->sk_family;
4242 else
4243 goto out;
4244
4245 if (sock && family == PF_UNIX)
4246 selinux_inode_getsecid(SOCK_INODE(sock), &peer_secid);
4247 else if (skb)
4248 selinux_skb_peerlbl_sid(skb, family, &peer_secid);
4249
4250 out:
4251 *secid = peer_secid;
4252 if (peer_secid == SECSID_NULL)
4253 return -EINVAL;
4254 return 0;
4255 }
4256
4257 static int selinux_sk_alloc_security(struct sock *sk, int family, gfp_t priority)
4258 {
4259 struct sk_security_struct *sksec;
4260
4261 sksec = kzalloc(sizeof(*sksec), priority);
4262 if (!sksec)
4263 return -ENOMEM;
4264
4265 sksec->peer_sid = SECINITSID_UNLABELED;
4266 sksec->sid = SECINITSID_UNLABELED;
4267 selinux_netlbl_sk_security_reset(sksec);
4268 sk->sk_security = sksec;
4269
4270 return 0;
4271 }
4272
4273 static void selinux_sk_free_security(struct sock *sk)
4274 {
4275 struct sk_security_struct *sksec = sk->sk_security;
4276
4277 sk->sk_security = NULL;
4278 selinux_netlbl_sk_security_free(sksec);
4279 kfree(sksec);
4280 }
4281
4282 static void selinux_sk_clone_security(const struct sock *sk, struct sock *newsk)
4283 {
4284 struct sk_security_struct *sksec = sk->sk_security;
4285 struct sk_security_struct *newsksec = newsk->sk_security;
4286
4287 newsksec->sid = sksec->sid;
4288 newsksec->peer_sid = sksec->peer_sid;
4289 newsksec->sclass = sksec->sclass;
4290
4291 selinux_netlbl_sk_security_reset(newsksec);
4292 }
4293
4294 static void selinux_sk_getsecid(struct sock *sk, u32 *secid)
4295 {
4296 if (!sk)
4297 *secid = SECINITSID_ANY_SOCKET;
4298 else {
4299 struct sk_security_struct *sksec = sk->sk_security;
4300
4301 *secid = sksec->sid;
4302 }
4303 }
4304
4305 static void selinux_sock_graft(struct sock *sk, struct socket *parent)
4306 {
4307 struct inode_security_struct *isec = SOCK_INODE(parent)->i_security;
4308 struct sk_security_struct *sksec = sk->sk_security;
4309
4310 if (sk->sk_family == PF_INET || sk->sk_family == PF_INET6 ||
4311 sk->sk_family == PF_UNIX)
4312 isec->sid = sksec->sid;
4313 sksec->sclass = isec->sclass;
4314 }
4315
4316 static int selinux_inet_conn_request(struct sock *sk, struct sk_buff *skb,
4317 struct request_sock *req)
4318 {
4319 struct sk_security_struct *sksec = sk->sk_security;
4320 int err;
4321 u16 family = sk->sk_family;
4322 u32 newsid;
4323 u32 peersid;
4324
4325 /* handle mapped IPv4 packets arriving via IPv6 sockets */
4326 if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
4327 family = PF_INET;
4328
4329 err = selinux_skb_peerlbl_sid(skb, family, &peersid);
4330 if (err)
4331 return err;
4332 if (peersid == SECSID_NULL) {
4333 req->secid = sksec->sid;
4334 req->peer_secid = SECSID_NULL;
4335 } else {
4336 err = security_sid_mls_copy(sksec->sid, peersid, &newsid);
4337 if (err)
4338 return err;
4339 req->secid = newsid;
4340 req->peer_secid = peersid;
4341 }
4342
4343 return selinux_netlbl_inet_conn_request(req, family);
4344 }
4345
4346 static void selinux_inet_csk_clone(struct sock *newsk,
4347 const struct request_sock *req)
4348 {
4349 struct sk_security_struct *newsksec = newsk->sk_security;
4350
4351 newsksec->sid = req->secid;
4352 newsksec->peer_sid = req->peer_secid;
4353 /* NOTE: Ideally, we should also get the isec->sid for the
4354 new socket in sync, but we don't have the isec available yet.
4355 So we will wait until sock_graft to do it, by which
4356 time it will have been created and available. */
4357
4358 /* We don't need to take any sort of lock here as we are the only
4359 * thread with access to newsksec */
4360 selinux_netlbl_inet_csk_clone(newsk, req->rsk_ops->family);
4361 }
4362
4363 static void selinux_inet_conn_established(struct sock *sk, struct sk_buff *skb)
4364 {
4365 u16 family = sk->sk_family;
4366 struct sk_security_struct *sksec = sk->sk_security;
4367
4368 /* handle mapped IPv4 packets arriving via IPv6 sockets */
4369 if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
4370 family = PF_INET;
4371
4372 selinux_skb_peerlbl_sid(skb, family, &sksec->peer_sid);
4373 }
4374
4375 static int selinux_secmark_relabel_packet(u32 sid)
4376 {
4377 const struct task_security_struct *__tsec;
4378 u32 tsid;
4379
4380 __tsec = current_security();
4381 tsid = __tsec->sid;
4382
4383 return avc_has_perm(tsid, sid, SECCLASS_PACKET, PACKET__RELABELTO, NULL);
4384 }
4385
4386 static void selinux_secmark_refcount_inc(void)
4387 {
4388 atomic_inc(&selinux_secmark_refcount);
4389 }
4390
4391 static void selinux_secmark_refcount_dec(void)
4392 {
4393 atomic_dec(&selinux_secmark_refcount);
4394 }
4395
4396 static void selinux_req_classify_flow(const struct request_sock *req,
4397 struct flowi *fl)
4398 {
4399 fl->flowi_secid = req->secid;
4400 }
4401
4402 static int selinux_tun_dev_create(void)
4403 {
4404 u32 sid = current_sid();
4405
4406 /* we aren't taking into account the "sockcreate" SID since the socket
4407 * that is being created here is not a socket in the traditional sense,
4408 * instead it is a private sock, accessible only to the kernel, and
4409 * representing a wide range of network traffic spanning multiple
4410 * connections unlike traditional sockets - check the TUN driver to
4411 * get a better understanding of why this socket is special */
4412
4413 return avc_has_perm(sid, sid, SECCLASS_TUN_SOCKET, TUN_SOCKET__CREATE,
4414 NULL);
4415 }
4416
4417 static void selinux_tun_dev_post_create(struct sock *sk)
4418 {
4419 struct sk_security_struct *sksec = sk->sk_security;
4420
4421 /* we don't currently perform any NetLabel based labeling here and it
4422 * isn't clear that we would want to do so anyway; while we could apply
4423 * labeling without the support of the TUN user the resulting labeled
4424 * traffic from the other end of the connection would almost certainly
4425 * cause confusion to the TUN user that had no idea network labeling
4426 * protocols were being used */
4427
4428 /* see the comments in selinux_tun_dev_create() about why we don't use
4429 * the sockcreate SID here */
4430
4431 sksec->sid = current_sid();
4432 sksec->sclass = SECCLASS_TUN_SOCKET;
4433 }
4434
4435 static int selinux_tun_dev_attach(struct sock *sk)
4436 {
4437 struct sk_security_struct *sksec = sk->sk_security;
4438 u32 sid = current_sid();
4439 int err;
4440
4441 err = avc_has_perm(sid, sksec->sid, SECCLASS_TUN_SOCKET,
4442 TUN_SOCKET__RELABELFROM, NULL);
4443 if (err)
4444 return err;
4445 err = avc_has_perm(sid, sid, SECCLASS_TUN_SOCKET,
4446 TUN_SOCKET__RELABELTO, NULL);
4447 if (err)
4448 return err;
4449
4450 sksec->sid = sid;
4451
4452 return 0;
4453 }
4454
4455 static int selinux_nlmsg_perm(struct sock *sk, struct sk_buff *skb)
4456 {
4457 int err = 0;
4458 u32 perm;
4459 struct nlmsghdr *nlh;
4460 struct sk_security_struct *sksec = sk->sk_security;
4461
4462 if (skb->len < NLMSG_SPACE(0)) {
4463 err = -EINVAL;
4464 goto out;
4465 }
4466 nlh = nlmsg_hdr(skb);
4467
4468 err = selinux_nlmsg_lookup(sksec->sclass, nlh->nlmsg_type, &perm);
4469 if (err) {
4470 if (err == -EINVAL) {
4471 audit_log(current->audit_context, GFP_KERNEL, AUDIT_SELINUX_ERR,
4472 "SELinux: unrecognized netlink message"
4473 " type=%hu for sclass=%hu\n",
4474 nlh->nlmsg_type, sksec->sclass);
4475 if (!selinux_enforcing || security_get_allow_unknown())
4476 err = 0;
4477 }
4478
4479 /* Ignore */
4480 if (err == -ENOENT)
4481 err = 0;
4482 goto out;
4483 }
4484
4485 err = sock_has_perm(current, sk, perm);
4486 out:
4487 return err;
4488 }
4489
4490 #ifdef CONFIG_NETFILTER
4491
4492 static unsigned int selinux_ip_forward(struct sk_buff *skb, int ifindex,
4493 u16 family)
4494 {
4495 int err;
4496 char *addrp;
4497 u32 peer_sid;
4498 struct common_audit_data ad;
4499 struct lsm_network_audit net = {0,};
4500 u8 secmark_active;
4501 u8 netlbl_active;
4502 u8 peerlbl_active;
4503
4504 if (!selinux_policycap_netpeer)
4505 return NF_ACCEPT;
4506
4507 secmark_active = selinux_secmark_enabled();
4508 netlbl_active = netlbl_enabled();
4509 peerlbl_active = netlbl_active || selinux_xfrm_enabled();
4510 if (!secmark_active && !peerlbl_active)
4511 return NF_ACCEPT;
4512
4513 if (selinux_skb_peerlbl_sid(skb, family, &peer_sid) != 0)
4514 return NF_DROP;
4515
4516 ad.type = LSM_AUDIT_DATA_NET;
4517 ad.u.net = &net;
4518 ad.u.net->netif = ifindex;
4519 ad.u.net->family = family;
4520 if (selinux_parse_skb(skb, &ad, &addrp, 1, NULL) != 0)
4521 return NF_DROP;
4522
4523 if (peerlbl_active) {
4524 err = selinux_inet_sys_rcv_skb(ifindex, addrp, family,
4525 peer_sid, &ad);
4526 if (err) {
4527 selinux_netlbl_err(skb, err, 1);
4528 return NF_DROP;
4529 }
4530 }
4531
4532 if (secmark_active)
4533 if (avc_has_perm(peer_sid, skb->secmark,
4534 SECCLASS_PACKET, PACKET__FORWARD_IN, &ad))
4535 return NF_DROP;
4536
4537 if (netlbl_active)
4538 /* we do this in the FORWARD path and not the POST_ROUTING
4539 * path because we want to make sure we apply the necessary
4540 * labeling before IPsec is applied so we can leverage AH
4541 * protection */
4542 if (selinux_netlbl_skbuff_setsid(skb, family, peer_sid) != 0)
4543 return NF_DROP;
4544
4545 return NF_ACCEPT;
4546 }
4547
4548 static unsigned int selinux_ipv4_forward(unsigned int hooknum,
4549 struct sk_buff *skb,
4550 const struct net_device *in,
4551 const struct net_device *out,
4552 int (*okfn)(struct sk_buff *))
4553 {
4554 return selinux_ip_forward(skb, in->ifindex, PF_INET);
4555 }
4556
4557 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
4558 static unsigned int selinux_ipv6_forward(unsigned int hooknum,
4559 struct sk_buff *skb,
4560 const struct net_device *in,
4561 const struct net_device *out,
4562 int (*okfn)(struct sk_buff *))
4563 {
4564 return selinux_ip_forward(skb, in->ifindex, PF_INET6);
4565 }
4566 #endif /* IPV6 */
4567
4568 static unsigned int selinux_ip_output(struct sk_buff *skb,
4569 u16 family)
4570 {
4571 u32 sid;
4572
4573 if (!netlbl_enabled())
4574 return NF_ACCEPT;
4575
4576 /* we do this in the LOCAL_OUT path and not the POST_ROUTING path
4577 * because we want to make sure we apply the necessary labeling
4578 * before IPsec is applied so we can leverage AH protection */
4579 if (skb->sk) {
4580 struct sk_security_struct *sksec = skb->sk->sk_security;
4581 sid = sksec->sid;
4582 } else
4583 sid = SECINITSID_KERNEL;
4584 if (selinux_netlbl_skbuff_setsid(skb, family, sid) != 0)
4585 return NF_DROP;
4586
4587 return NF_ACCEPT;
4588 }
4589
4590 static unsigned int selinux_ipv4_output(unsigned int hooknum,
4591 struct sk_buff *skb,
4592 const struct net_device *in,
4593 const struct net_device *out,
4594 int (*okfn)(struct sk_buff *))
4595 {
4596 return selinux_ip_output(skb, PF_INET);
4597 }
4598
4599 static unsigned int selinux_ip_postroute_compat(struct sk_buff *skb,
4600 int ifindex,
4601 u16 family)
4602 {
4603 struct sock *sk = skb->sk;
4604 struct sk_security_struct *sksec;
4605 struct common_audit_data ad;
4606 struct lsm_network_audit net = {0,};
4607 char *addrp;
4608 u8 proto;
4609
4610 if (sk == NULL)
4611 return NF_ACCEPT;
4612 sksec = sk->sk_security;
4613
4614 ad.type = LSM_AUDIT_DATA_NET;
4615 ad.u.net = &net;
4616 ad.u.net->netif = ifindex;
4617 ad.u.net->family = family;
4618 if (selinux_parse_skb(skb, &ad, &addrp, 0, &proto))
4619 return NF_DROP;
4620
4621 if (selinux_secmark_enabled())
4622 if (avc_has_perm(sksec->sid, skb->secmark,
4623 SECCLASS_PACKET, PACKET__SEND, &ad))
4624 return NF_DROP_ERR(-ECONNREFUSED);
4625
4626 if (selinux_xfrm_postroute_last(sksec->sid, skb, &ad, proto))
4627 return NF_DROP_ERR(-ECONNREFUSED);
4628
4629 return NF_ACCEPT;
4630 }
4631
4632 static unsigned int selinux_ip_postroute(struct sk_buff *skb, int ifindex,
4633 u16 family)
4634 {
4635 u32 secmark_perm;
4636 u32 peer_sid;
4637 struct sock *sk;
4638 struct common_audit_data ad;
4639 struct lsm_network_audit net = {0,};
4640 char *addrp;
4641 u8 secmark_active;
4642 u8 peerlbl_active;
4643
4644 /* If any sort of compatibility mode is enabled then handoff processing
4645 * to the selinux_ip_postroute_compat() function to deal with the
4646 * special handling. We do this in an attempt to keep this function
4647 * as fast and as clean as possible. */
4648 if (!selinux_policycap_netpeer)
4649 return selinux_ip_postroute_compat(skb, ifindex, family);
4650 #ifdef CONFIG_XFRM
4651 /* If skb->dst->xfrm is non-NULL then the packet is undergoing an IPsec
4652 * packet transformation so allow the packet to pass without any checks
4653 * since we'll have another chance to perform access control checks
4654 * when the packet is on it's final way out.
4655 * NOTE: there appear to be some IPv6 multicast cases where skb->dst
4656 * is NULL, in this case go ahead and apply access control. */
4657 if (skb_dst(skb) != NULL && skb_dst(skb)->xfrm != NULL)
4658 return NF_ACCEPT;
4659 #endif
4660 secmark_active = selinux_secmark_enabled();
4661 peerlbl_active = netlbl_enabled() || selinux_xfrm_enabled();
4662 if (!secmark_active && !peerlbl_active)
4663 return NF_ACCEPT;
4664
4665 /* if the packet is being forwarded then get the peer label from the
4666 * packet itself; otherwise check to see if it is from a local
4667 * application or the kernel, if from an application get the peer label
4668 * from the sending socket, otherwise use the kernel's sid */
4669 sk = skb->sk;
4670 if (sk == NULL) {
4671 if (skb->skb_iif) {
4672 secmark_perm = PACKET__FORWARD_OUT;
4673 if (selinux_skb_peerlbl_sid(skb, family, &peer_sid))
4674 return NF_DROP;
4675 } else {
4676 secmark_perm = PACKET__SEND;
4677 peer_sid = SECINITSID_KERNEL;
4678 }
4679 } else {
4680 struct sk_security_struct *sksec = sk->sk_security;
4681 peer_sid = sksec->sid;
4682 secmark_perm = PACKET__SEND;
4683 }
4684
4685 ad.type = LSM_AUDIT_DATA_NET;
4686 ad.u.net = &net;
4687 ad.u.net->netif = ifindex;
4688 ad.u.net->family = family;
4689 if (selinux_parse_skb(skb, &ad, &addrp, 0, NULL))
4690 return NF_DROP;
4691
4692 if (secmark_active)
4693 if (avc_has_perm(peer_sid, skb->secmark,
4694 SECCLASS_PACKET, secmark_perm, &ad))
4695 return NF_DROP_ERR(-ECONNREFUSED);
4696
4697 if (peerlbl_active) {
4698 u32 if_sid;
4699 u32 node_sid;
4700
4701 if (sel_netif_sid(ifindex, &if_sid))
4702 return NF_DROP;
4703 if (avc_has_perm(peer_sid, if_sid,
4704 SECCLASS_NETIF, NETIF__EGRESS, &ad))
4705 return NF_DROP_ERR(-ECONNREFUSED);
4706
4707 if (sel_netnode_sid(addrp, family, &node_sid))
4708 return NF_DROP;
4709 if (avc_has_perm(peer_sid, node_sid,
4710 SECCLASS_NODE, NODE__SENDTO, &ad))
4711 return NF_DROP_ERR(-ECONNREFUSED);
4712 }
4713
4714 return NF_ACCEPT;
4715 }
4716
4717 static unsigned int selinux_ipv4_postroute(unsigned int hooknum,
4718 struct sk_buff *skb,
4719 const struct net_device *in,
4720 const struct net_device *out,
4721 int (*okfn)(struct sk_buff *))
4722 {
4723 return selinux_ip_postroute(skb, out->ifindex, PF_INET);
4724 }
4725
4726 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
4727 static unsigned int selinux_ipv6_postroute(unsigned int hooknum,
4728 struct sk_buff *skb,
4729 const struct net_device *in,
4730 const struct net_device *out,
4731 int (*okfn)(struct sk_buff *))
4732 {
4733 return selinux_ip_postroute(skb, out->ifindex, PF_INET6);
4734 }
4735 #endif /* IPV6 */
4736
4737 #endif /* CONFIG_NETFILTER */
4738
4739 static int selinux_netlink_send(struct sock *sk, struct sk_buff *skb)
4740 {
4741 int err;
4742
4743 err = cap_netlink_send(sk, skb);
4744 if (err)
4745 return err;
4746
4747 return selinux_nlmsg_perm(sk, skb);
4748 }
4749
4750 static int ipc_alloc_security(struct task_struct *task,
4751 struct kern_ipc_perm *perm,
4752 u16 sclass)
4753 {
4754 struct ipc_security_struct *isec;
4755 u32 sid;
4756
4757 isec = kzalloc(sizeof(struct ipc_security_struct), GFP_KERNEL);
4758 if (!isec)
4759 return -ENOMEM;
4760
4761 sid = task_sid(task);
4762 isec->sclass = sclass;
4763 isec->sid = sid;
4764 perm->security = isec;
4765
4766 return 0;
4767 }
4768
4769 static void ipc_free_security(struct kern_ipc_perm *perm)
4770 {
4771 struct ipc_security_struct *isec = perm->security;
4772 perm->security = NULL;
4773 kfree(isec);
4774 }
4775
4776 static int msg_msg_alloc_security(struct msg_msg *msg)
4777 {
4778 struct msg_security_struct *msec;
4779
4780 msec = kzalloc(sizeof(struct msg_security_struct), GFP_KERNEL);
4781 if (!msec)
4782 return -ENOMEM;
4783
4784 msec->sid = SECINITSID_UNLABELED;
4785 msg->security = msec;
4786
4787 return 0;
4788 }
4789
4790 static void msg_msg_free_security(struct msg_msg *msg)
4791 {
4792 struct msg_security_struct *msec = msg->security;
4793
4794 msg->security = NULL;
4795 kfree(msec);
4796 }
4797
4798 static int ipc_has_perm(struct kern_ipc_perm *ipc_perms,
4799 u32 perms)
4800 {
4801 struct ipc_security_struct *isec;
4802 struct common_audit_data ad;
4803 u32 sid = current_sid();
4804
4805 isec = ipc_perms->security;
4806
4807 ad.type = LSM_AUDIT_DATA_IPC;
4808 ad.u.ipc_id = ipc_perms->key;
4809
4810 return avc_has_perm(sid, isec->sid, isec->sclass, perms, &ad);
4811 }
4812
4813 static int selinux_msg_msg_alloc_security(struct msg_msg *msg)
4814 {
4815 return msg_msg_alloc_security(msg);
4816 }
4817
4818 static void selinux_msg_msg_free_security(struct msg_msg *msg)
4819 {
4820 msg_msg_free_security(msg);
4821 }
4822
4823 /* message queue security operations */
4824 static int selinux_msg_queue_alloc_security(struct msg_queue *msq)
4825 {
4826 struct ipc_security_struct *isec;
4827 struct common_audit_data ad;
4828 u32 sid = current_sid();
4829 int rc;
4830
4831 rc = ipc_alloc_security(current, &msq->q_perm, SECCLASS_MSGQ);
4832 if (rc)
4833 return rc;
4834
4835 isec = msq->q_perm.security;
4836
4837 ad.type = LSM_AUDIT_DATA_IPC;
4838 ad.u.ipc_id = msq->q_perm.key;
4839
4840 rc = avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
4841 MSGQ__CREATE, &ad);
4842 if (rc) {
4843 ipc_free_security(&msq->q_perm);
4844 return rc;
4845 }
4846 return 0;
4847 }
4848
4849 static void selinux_msg_queue_free_security(struct msg_queue *msq)
4850 {
4851 ipc_free_security(&msq->q_perm);
4852 }
4853
4854 static int selinux_msg_queue_associate(struct msg_queue *msq, int msqflg)
4855 {
4856 struct ipc_security_struct *isec;
4857 struct common_audit_data ad;
4858 u32 sid = current_sid();
4859
4860 isec = msq->q_perm.security;
4861
4862 ad.type = LSM_AUDIT_DATA_IPC;
4863 ad.u.ipc_id = msq->q_perm.key;
4864
4865 return avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
4866 MSGQ__ASSOCIATE, &ad);
4867 }
4868
4869 static int selinux_msg_queue_msgctl(struct msg_queue *msq, int cmd)
4870 {
4871 int err;
4872 int perms;
4873
4874 switch (cmd) {
4875 case IPC_INFO:
4876 case MSG_INFO:
4877 /* No specific object, just general system-wide information. */
4878 return task_has_system(current, SYSTEM__IPC_INFO);
4879 case IPC_STAT:
4880 case MSG_STAT:
4881 perms = MSGQ__GETATTR | MSGQ__ASSOCIATE;
4882 break;
4883 case IPC_SET:
4884 perms = MSGQ__SETATTR;
4885 break;
4886 case IPC_RMID:
4887 perms = MSGQ__DESTROY;
4888 break;
4889 default:
4890 return 0;
4891 }
4892
4893 err = ipc_has_perm(&msq->q_perm, perms);
4894 return err;
4895 }
4896
4897 static int selinux_msg_queue_msgsnd(struct msg_queue *msq, struct msg_msg *msg, int msqflg)
4898 {
4899 struct ipc_security_struct *isec;
4900 struct msg_security_struct *msec;
4901 struct common_audit_data ad;
4902 u32 sid = current_sid();
4903 int rc;
4904
4905 isec = msq->q_perm.security;
4906 msec = msg->security;
4907
4908 /*
4909 * First time through, need to assign label to the message
4910 */
4911 if (msec->sid == SECINITSID_UNLABELED) {
4912 /*
4913 * Compute new sid based on current process and
4914 * message queue this message will be stored in
4915 */
4916 rc = security_transition_sid(sid, isec->sid, SECCLASS_MSG,
4917 NULL, &msec->sid);
4918 if (rc)
4919 return rc;
4920 }
4921
4922 ad.type = LSM_AUDIT_DATA_IPC;
4923 ad.u.ipc_id = msq->q_perm.key;
4924
4925 /* Can this process write to the queue? */
4926 rc = avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
4927 MSGQ__WRITE, &ad);
4928 if (!rc)
4929 /* Can this process send the message */
4930 rc = avc_has_perm(sid, msec->sid, SECCLASS_MSG,
4931 MSG__SEND, &ad);
4932 if (!rc)
4933 /* Can the message be put in the queue? */
4934 rc = avc_has_perm(msec->sid, isec->sid, SECCLASS_MSGQ,
4935 MSGQ__ENQUEUE, &ad);
4936
4937 return rc;
4938 }
4939
4940 static int selinux_msg_queue_msgrcv(struct msg_queue *msq, struct msg_msg *msg,
4941 struct task_struct *target,
4942 long type, int mode)
4943 {
4944 struct ipc_security_struct *isec;
4945 struct msg_security_struct *msec;
4946 struct common_audit_data ad;
4947 u32 sid = task_sid(target);
4948 int rc;
4949
4950 isec = msq->q_perm.security;
4951 msec = msg->security;
4952
4953 ad.type = LSM_AUDIT_DATA_IPC;
4954 ad.u.ipc_id = msq->q_perm.key;
4955
4956 rc = avc_has_perm(sid, isec->sid,
4957 SECCLASS_MSGQ, MSGQ__READ, &ad);
4958 if (!rc)
4959 rc = avc_has_perm(sid, msec->sid,
4960 SECCLASS_MSG, MSG__RECEIVE, &ad);
4961 return rc;
4962 }
4963
4964 /* Shared Memory security operations */
4965 static int selinux_shm_alloc_security(struct shmid_kernel *shp)
4966 {
4967 struct ipc_security_struct *isec;
4968 struct common_audit_data ad;
4969 u32 sid = current_sid();
4970 int rc;
4971
4972 rc = ipc_alloc_security(current, &shp->shm_perm, SECCLASS_SHM);
4973 if (rc)
4974 return rc;
4975
4976 isec = shp->shm_perm.security;
4977
4978 ad.type = LSM_AUDIT_DATA_IPC;
4979 ad.u.ipc_id = shp->shm_perm.key;
4980
4981 rc = avc_has_perm(sid, isec->sid, SECCLASS_SHM,
4982 SHM__CREATE, &ad);
4983 if (rc) {
4984 ipc_free_security(&shp->shm_perm);
4985 return rc;
4986 }
4987 return 0;
4988 }
4989
4990 static void selinux_shm_free_security(struct shmid_kernel *shp)
4991 {
4992 ipc_free_security(&shp->shm_perm);
4993 }
4994
4995 static int selinux_shm_associate(struct shmid_kernel *shp, int shmflg)
4996 {
4997 struct ipc_security_struct *isec;
4998 struct common_audit_data ad;
4999 u32 sid = current_sid();
5000
5001 isec = shp->shm_perm.security;
5002
5003 ad.type = LSM_AUDIT_DATA_IPC;
5004 ad.u.ipc_id = shp->shm_perm.key;
5005
5006 return avc_has_perm(sid, isec->sid, SECCLASS_SHM,
5007 SHM__ASSOCIATE, &ad);
5008 }
5009
5010 /* Note, at this point, shp is locked down */
5011 static int selinux_shm_shmctl(struct shmid_kernel *shp, int cmd)
5012 {
5013 int perms;
5014 int err;
5015
5016 switch (cmd) {
5017 case IPC_INFO:
5018 case SHM_INFO:
5019 /* No specific object, just general system-wide information. */
5020 return task_has_system(current, SYSTEM__IPC_INFO);
5021 case IPC_STAT:
5022 case SHM_STAT:
5023 perms = SHM__GETATTR | SHM__ASSOCIATE;
5024 break;
5025 case IPC_SET:
5026 perms = SHM__SETATTR;
5027 break;
5028 case SHM_LOCK:
5029 case SHM_UNLOCK:
5030 perms = SHM__LOCK;
5031 break;
5032 case IPC_RMID:
5033 perms = SHM__DESTROY;
5034 break;
5035 default:
5036 return 0;
5037 }
5038
5039 err = ipc_has_perm(&shp->shm_perm, perms);
5040 return err;
5041 }
5042
5043 static int selinux_shm_shmat(struct shmid_kernel *shp,
5044 char __user *shmaddr, int shmflg)
5045 {
5046 u32 perms;
5047
5048 if (shmflg & SHM_RDONLY)
5049 perms = SHM__READ;
5050 else
5051 perms = SHM__READ | SHM__WRITE;
5052
5053 return ipc_has_perm(&shp->shm_perm, perms);
5054 }
5055
5056 /* Semaphore security operations */
5057 static int selinux_sem_alloc_security(struct sem_array *sma)
5058 {
5059 struct ipc_security_struct *isec;
5060 struct common_audit_data ad;
5061 u32 sid = current_sid();
5062 int rc;
5063
5064 rc = ipc_alloc_security(current, &sma->sem_perm, SECCLASS_SEM);
5065 if (rc)
5066 return rc;
5067
5068 isec = sma->sem_perm.security;
5069
5070 ad.type = LSM_AUDIT_DATA_IPC;
5071 ad.u.ipc_id = sma->sem_perm.key;
5072
5073 rc = avc_has_perm(sid, isec->sid, SECCLASS_SEM,
5074 SEM__CREATE, &ad);
5075 if (rc) {
5076 ipc_free_security(&sma->sem_perm);
5077 return rc;
5078 }
5079 return 0;
5080 }
5081
5082 static void selinux_sem_free_security(struct sem_array *sma)
5083 {
5084 ipc_free_security(&sma->sem_perm);
5085 }
5086
5087 static int selinux_sem_associate(struct sem_array *sma, int semflg)
5088 {
5089 struct ipc_security_struct *isec;
5090 struct common_audit_data ad;
5091 u32 sid = current_sid();
5092
5093 isec = sma->sem_perm.security;
5094
5095 ad.type = LSM_AUDIT_DATA_IPC;
5096 ad.u.ipc_id = sma->sem_perm.key;
5097
5098 return avc_has_perm(sid, isec->sid, SECCLASS_SEM,
5099 SEM__ASSOCIATE, &ad);
5100 }
5101
5102 /* Note, at this point, sma is locked down */
5103 static int selinux_sem_semctl(struct sem_array *sma, int cmd)
5104 {
5105 int err;
5106 u32 perms;
5107
5108 switch (cmd) {
5109 case IPC_INFO:
5110 case SEM_INFO:
5111 /* No specific object, just general system-wide information. */
5112 return task_has_system(current, SYSTEM__IPC_INFO);
5113 case GETPID:
5114 case GETNCNT:
5115 case GETZCNT:
5116 perms = SEM__GETATTR;
5117 break;
5118 case GETVAL:
5119 case GETALL:
5120 perms = SEM__READ;
5121 break;
5122 case SETVAL:
5123 case SETALL:
5124 perms = SEM__WRITE;
5125 break;
5126 case IPC_RMID:
5127 perms = SEM__DESTROY;
5128 break;
5129 case IPC_SET:
5130 perms = SEM__SETATTR;
5131 break;
5132 case IPC_STAT:
5133 case SEM_STAT:
5134 perms = SEM__GETATTR | SEM__ASSOCIATE;
5135 break;
5136 default:
5137 return 0;
5138 }
5139
5140 err = ipc_has_perm(&sma->sem_perm, perms);
5141 return err;
5142 }
5143
5144 static int selinux_sem_semop(struct sem_array *sma,
5145 struct sembuf *sops, unsigned nsops, int alter)
5146 {
5147 u32 perms;
5148
5149 if (alter)
5150 perms = SEM__READ | SEM__WRITE;
5151 else
5152 perms = SEM__READ;
5153
5154 return ipc_has_perm(&sma->sem_perm, perms);
5155 }
5156
5157 static int selinux_ipc_permission(struct kern_ipc_perm *ipcp, short flag)
5158 {
5159 u32 av = 0;
5160
5161 av = 0;
5162 if (flag & S_IRUGO)
5163 av |= IPC__UNIX_READ;
5164 if (flag & S_IWUGO)
5165 av |= IPC__UNIX_WRITE;
5166
5167 if (av == 0)
5168 return 0;
5169
5170 return ipc_has_perm(ipcp, av);
5171 }
5172
5173 static void selinux_ipc_getsecid(struct kern_ipc_perm *ipcp, u32 *secid)
5174 {
5175 struct ipc_security_struct *isec = ipcp->security;
5176 *secid = isec->sid;
5177 }
5178
5179 static void selinux_d_instantiate(struct dentry *dentry, struct inode *inode)
5180 {
5181 if (inode)
5182 inode_doinit_with_dentry(inode, dentry);
5183 }
5184
5185 static int selinux_getprocattr(struct task_struct *p,
5186 char *name, char **value)
5187 {
5188 const struct task_security_struct *__tsec;
5189 u32 sid;
5190 int error;
5191 unsigned len;
5192
5193 if (current != p) {
5194 error = current_has_perm(p, PROCESS__GETATTR);
5195 if (error)
5196 return error;
5197 }
5198
5199 rcu_read_lock();
5200 __tsec = __task_cred(p)->security;
5201
5202 if (!strcmp(name, "current"))
5203 sid = __tsec->sid;
5204 else if (!strcmp(name, "prev"))
5205 sid = __tsec->osid;
5206 else if (!strcmp(name, "exec"))
5207 sid = __tsec->exec_sid;
5208 else if (!strcmp(name, "fscreate"))
5209 sid = __tsec->create_sid;
5210 else if (!strcmp(name, "keycreate"))
5211 sid = __tsec->keycreate_sid;
5212 else if (!strcmp(name, "sockcreate"))
5213 sid = __tsec->sockcreate_sid;
5214 else
5215 goto invalid;
5216 rcu_read_unlock();
5217
5218 if (!sid)
5219 return 0;
5220
5221 error = security_sid_to_context(sid, value, &len);
5222 if (error)
5223 return error;
5224 return len;
5225
5226 invalid:
5227 rcu_read_unlock();
5228 return -EINVAL;
5229 }
5230
5231 static int selinux_setprocattr(struct task_struct *p,
5232 char *name, void *value, size_t size)
5233 {
5234 struct task_security_struct *tsec;
5235 struct task_struct *tracer;
5236 struct cred *new;
5237 u32 sid = 0, ptsid;
5238 int error;
5239 char *str = value;
5240
5241 if (current != p) {
5242 /* SELinux only allows a process to change its own
5243 security attributes. */
5244 return -EACCES;
5245 }
5246
5247 /*
5248 * Basic control over ability to set these attributes at all.
5249 * current == p, but we'll pass them separately in case the
5250 * above restriction is ever removed.
5251 */
5252 if (!strcmp(name, "exec"))
5253 error = current_has_perm(p, PROCESS__SETEXEC);
5254 else if (!strcmp(name, "fscreate"))
5255 error = current_has_perm(p, PROCESS__SETFSCREATE);
5256 else if (!strcmp(name, "keycreate"))
5257 error = current_has_perm(p, PROCESS__SETKEYCREATE);
5258 else if (!strcmp(name, "sockcreate"))
5259 error = current_has_perm(p, PROCESS__SETSOCKCREATE);
5260 else if (!strcmp(name, "current"))
5261 error = current_has_perm(p, PROCESS__SETCURRENT);
5262 else
5263 error = -EINVAL;
5264 if (error)
5265 return error;
5266
5267 /* Obtain a SID for the context, if one was specified. */
5268 if (size && str[1] && str[1] != '\n') {
5269 if (str[size-1] == '\n') {
5270 str[size-1] = 0;
5271 size--;
5272 }
5273 error = security_context_to_sid(value, size, &sid);
5274 if (error == -EINVAL && !strcmp(name, "fscreate")) {
5275 if (!capable(CAP_MAC_ADMIN)) {
5276 struct audit_buffer *ab;
5277 size_t audit_size;
5278
5279 /* We strip a nul only if it is at the end, otherwise the
5280 * context contains a nul and we should audit that */
5281 if (str[size - 1] == '\0')
5282 audit_size = size - 1;
5283 else
5284 audit_size = size;
5285 ab = audit_log_start(current->audit_context, GFP_ATOMIC, AUDIT_SELINUX_ERR);
5286 audit_log_format(ab, "op=fscreate invalid_context=");
5287 audit_log_n_untrustedstring(ab, value, audit_size);
5288 audit_log_end(ab);
5289
5290 return error;
5291 }
5292 error = security_context_to_sid_force(value, size,
5293 &sid);
5294 }
5295 if (error)
5296 return error;
5297 }
5298
5299 new = prepare_creds();
5300 if (!new)
5301 return -ENOMEM;
5302
5303 /* Permission checking based on the specified context is
5304 performed during the actual operation (execve,
5305 open/mkdir/...), when we know the full context of the
5306 operation. See selinux_bprm_set_creds for the execve
5307 checks and may_create for the file creation checks. The
5308 operation will then fail if the context is not permitted. */
5309 tsec = new->security;
5310 if (!strcmp(name, "exec")) {
5311 tsec->exec_sid = sid;
5312 } else if (!strcmp(name, "fscreate")) {
5313 tsec->create_sid = sid;
5314 } else if (!strcmp(name, "keycreate")) {
5315 error = may_create_key(sid, p);
5316 if (error)
5317 goto abort_change;
5318 tsec->keycreate_sid = sid;
5319 } else if (!strcmp(name, "sockcreate")) {
5320 tsec->sockcreate_sid = sid;
5321 } else if (!strcmp(name, "current")) {
5322 error = -EINVAL;
5323 if (sid == 0)
5324 goto abort_change;
5325
5326 /* Only allow single threaded processes to change context */
5327 error = -EPERM;
5328 if (!current_is_single_threaded()) {
5329 error = security_bounded_transition(tsec->sid, sid);
5330 if (error)
5331 goto abort_change;
5332 }
5333
5334 /* Check permissions for the transition. */
5335 error = avc_has_perm(tsec->sid, sid, SECCLASS_PROCESS,
5336 PROCESS__DYNTRANSITION, NULL);
5337 if (error)
5338 goto abort_change;
5339
5340 /* Check for ptracing, and update the task SID if ok.
5341 Otherwise, leave SID unchanged and fail. */
5342 ptsid = 0;
5343 task_lock(p);
5344 tracer = ptrace_parent(p);
5345 if (tracer)
5346 ptsid = task_sid(tracer);
5347 task_unlock(p);
5348
5349 if (tracer) {
5350 error = avc_has_perm(ptsid, sid, SECCLASS_PROCESS,
5351 PROCESS__PTRACE, NULL);
5352 if (error)
5353 goto abort_change;
5354 }
5355
5356 tsec->sid = sid;
5357 } else {
5358 error = -EINVAL;
5359 goto abort_change;
5360 }
5361
5362 commit_creds(new);
5363 return size;
5364
5365 abort_change:
5366 abort_creds(new);
5367 return error;
5368 }
5369
5370 static int selinux_secid_to_secctx(u32 secid, char **secdata, u32 *seclen)
5371 {
5372 return security_sid_to_context(secid, secdata, seclen);
5373 }
5374
5375 static int selinux_secctx_to_secid(const char *secdata, u32 seclen, u32 *secid)
5376 {
5377 return security_context_to_sid(secdata, seclen, secid);
5378 }
5379
5380 static void selinux_release_secctx(char *secdata, u32 seclen)
5381 {
5382 kfree(secdata);
5383 }
5384
5385 /*
5386 * called with inode->i_mutex locked
5387 */
5388 static int selinux_inode_notifysecctx(struct inode *inode, void *ctx, u32 ctxlen)
5389 {
5390 return selinux_inode_setsecurity(inode, XATTR_SELINUX_SUFFIX, ctx, ctxlen, 0);
5391 }
5392
5393 /*
5394 * called with inode->i_mutex locked
5395 */
5396 static int selinux_inode_setsecctx(struct dentry *dentry, void *ctx, u32 ctxlen)
5397 {
5398 return __vfs_setxattr_noperm(dentry, XATTR_NAME_SELINUX, ctx, ctxlen, 0);
5399 }
5400
5401 static int selinux_inode_getsecctx(struct inode *inode, void **ctx, u32 *ctxlen)
5402 {
5403 int len = 0;
5404 len = selinux_inode_getsecurity(inode, XATTR_SELINUX_SUFFIX,
5405 ctx, true);
5406 if (len < 0)
5407 return len;
5408 *ctxlen = len;
5409 return 0;
5410 }
5411 #ifdef CONFIG_KEYS
5412
5413 static int selinux_key_alloc(struct key *k, const struct cred *cred,
5414 unsigned long flags)
5415 {
5416 const struct task_security_struct *tsec;
5417 struct key_security_struct *ksec;
5418
5419 ksec = kzalloc(sizeof(struct key_security_struct), GFP_KERNEL);
5420 if (!ksec)
5421 return -ENOMEM;
5422
5423 tsec = cred->security;
5424 if (tsec->keycreate_sid)
5425 ksec->sid = tsec->keycreate_sid;
5426 else
5427 ksec->sid = tsec->sid;
5428
5429 k->security = ksec;
5430 return 0;
5431 }
5432
5433 static void selinux_key_free(struct key *k)
5434 {
5435 struct key_security_struct *ksec = k->security;
5436
5437 k->security = NULL;
5438 kfree(ksec);
5439 }
5440
5441 static int selinux_key_permission(key_ref_t key_ref,
5442 const struct cred *cred,
5443 key_perm_t perm)
5444 {
5445 struct key *key;
5446 struct key_security_struct *ksec;
5447 u32 sid;
5448
5449 /* if no specific permissions are requested, we skip the
5450 permission check. No serious, additional covert channels
5451 appear to be created. */
5452 if (perm == 0)
5453 return 0;
5454
5455 sid = cred_sid(cred);
5456
5457 key = key_ref_to_ptr(key_ref);
5458 ksec = key->security;
5459
5460 return avc_has_perm(sid, ksec->sid, SECCLASS_KEY, perm, NULL);
5461 }
5462
5463 static int selinux_key_getsecurity(struct key *key, char **_buffer)
5464 {
5465 struct key_security_struct *ksec = key->security;
5466 char *context = NULL;
5467 unsigned len;
5468 int rc;
5469
5470 rc = security_sid_to_context(ksec->sid, &context, &len);
5471 if (!rc)
5472 rc = len;
5473 *_buffer = context;
5474 return rc;
5475 }
5476
5477 #endif
5478
5479 static struct security_operations selinux_ops = {
5480 .name = "selinux",
5481
5482 .ptrace_access_check = selinux_ptrace_access_check,
5483 .ptrace_traceme = selinux_ptrace_traceme,
5484 .capget = selinux_capget,
5485 .capset = selinux_capset,
5486 .capable = selinux_capable,
5487 .quotactl = selinux_quotactl,
5488 .quota_on = selinux_quota_on,
5489 .syslog = selinux_syslog,
5490 .vm_enough_memory = selinux_vm_enough_memory,
5491
5492 .netlink_send = selinux_netlink_send,
5493
5494 .bprm_set_creds = selinux_bprm_set_creds,
5495 .bprm_committing_creds = selinux_bprm_committing_creds,
5496 .bprm_committed_creds = selinux_bprm_committed_creds,
5497 .bprm_secureexec = selinux_bprm_secureexec,
5498
5499 .sb_alloc_security = selinux_sb_alloc_security,
5500 .sb_free_security = selinux_sb_free_security,
5501 .sb_copy_data = selinux_sb_copy_data,
5502 .sb_remount = selinux_sb_remount,
5503 .sb_kern_mount = selinux_sb_kern_mount,
5504 .sb_show_options = selinux_sb_show_options,
5505 .sb_statfs = selinux_sb_statfs,
5506 .sb_mount = selinux_mount,
5507 .sb_umount = selinux_umount,
5508 .sb_set_mnt_opts = selinux_set_mnt_opts,
5509 .sb_clone_mnt_opts = selinux_sb_clone_mnt_opts,
5510 .sb_parse_opts_str = selinux_parse_opts_str,
5511
5512
5513 .inode_alloc_security = selinux_inode_alloc_security,
5514 .inode_free_security = selinux_inode_free_security,
5515 .inode_init_security = selinux_inode_init_security,
5516 .inode_create = selinux_inode_create,
5517 .inode_link = selinux_inode_link,
5518 .inode_unlink = selinux_inode_unlink,
5519 .inode_symlink = selinux_inode_symlink,
5520 .inode_mkdir = selinux_inode_mkdir,
5521 .inode_rmdir = selinux_inode_rmdir,
5522 .inode_mknod = selinux_inode_mknod,
5523 .inode_rename = selinux_inode_rename,
5524 .inode_readlink = selinux_inode_readlink,
5525 .inode_follow_link = selinux_inode_follow_link,
5526 .inode_permission = selinux_inode_permission,
5527 .inode_setattr = selinux_inode_setattr,
5528 .inode_getattr = selinux_inode_getattr,
5529 .inode_setxattr = selinux_inode_setxattr,
5530 .inode_post_setxattr = selinux_inode_post_setxattr,
5531 .inode_getxattr = selinux_inode_getxattr,
5532 .inode_listxattr = selinux_inode_listxattr,
5533 .inode_removexattr = selinux_inode_removexattr,
5534 .inode_getsecurity = selinux_inode_getsecurity,
5535 .inode_setsecurity = selinux_inode_setsecurity,
5536 .inode_listsecurity = selinux_inode_listsecurity,
5537 .inode_getsecid = selinux_inode_getsecid,
5538
5539 .file_permission = selinux_file_permission,
5540 .file_alloc_security = selinux_file_alloc_security,
5541 .file_free_security = selinux_file_free_security,
5542 .file_ioctl = selinux_file_ioctl,
5543 .mmap_file = selinux_mmap_file,
5544 .mmap_addr = selinux_mmap_addr,
5545 .file_mprotect = selinux_file_mprotect,
5546 .file_lock = selinux_file_lock,
5547 .file_fcntl = selinux_file_fcntl,
5548 .file_set_fowner = selinux_file_set_fowner,
5549 .file_send_sigiotask = selinux_file_send_sigiotask,
5550 .file_receive = selinux_file_receive,
5551
5552 .file_open = selinux_file_open,
5553
5554 .task_create = selinux_task_create,
5555 .cred_alloc_blank = selinux_cred_alloc_blank,
5556 .cred_free = selinux_cred_free,
5557 .cred_prepare = selinux_cred_prepare,
5558 .cred_transfer = selinux_cred_transfer,
5559 .kernel_act_as = selinux_kernel_act_as,
5560 .kernel_create_files_as = selinux_kernel_create_files_as,
5561 .kernel_module_request = selinux_kernel_module_request,
5562 .task_setpgid = selinux_task_setpgid,
5563 .task_getpgid = selinux_task_getpgid,
5564 .task_getsid = selinux_task_getsid,
5565 .task_getsecid = selinux_task_getsecid,
5566 .task_setnice = selinux_task_setnice,
5567 .task_setioprio = selinux_task_setioprio,
5568 .task_getioprio = selinux_task_getioprio,
5569 .task_setrlimit = selinux_task_setrlimit,
5570 .task_setscheduler = selinux_task_setscheduler,
5571 .task_getscheduler = selinux_task_getscheduler,
5572 .task_movememory = selinux_task_movememory,
5573 .task_kill = selinux_task_kill,
5574 .task_wait = selinux_task_wait,
5575 .task_to_inode = selinux_task_to_inode,
5576
5577 .ipc_permission = selinux_ipc_permission,
5578 .ipc_getsecid = selinux_ipc_getsecid,
5579
5580 .msg_msg_alloc_security = selinux_msg_msg_alloc_security,
5581 .msg_msg_free_security = selinux_msg_msg_free_security,
5582
5583 .msg_queue_alloc_security = selinux_msg_queue_alloc_security,
5584 .msg_queue_free_security = selinux_msg_queue_free_security,
5585 .msg_queue_associate = selinux_msg_queue_associate,
5586 .msg_queue_msgctl = selinux_msg_queue_msgctl,
5587 .msg_queue_msgsnd = selinux_msg_queue_msgsnd,
5588 .msg_queue_msgrcv = selinux_msg_queue_msgrcv,
5589
5590 .shm_alloc_security = selinux_shm_alloc_security,
5591 .shm_free_security = selinux_shm_free_security,
5592 .shm_associate = selinux_shm_associate,
5593 .shm_shmctl = selinux_shm_shmctl,
5594 .shm_shmat = selinux_shm_shmat,
5595
5596 .sem_alloc_security = selinux_sem_alloc_security,
5597 .sem_free_security = selinux_sem_free_security,
5598 .sem_associate = selinux_sem_associate,
5599 .sem_semctl = selinux_sem_semctl,
5600 .sem_semop = selinux_sem_semop,
5601
5602 .d_instantiate = selinux_d_instantiate,
5603
5604 .getprocattr = selinux_getprocattr,
5605 .setprocattr = selinux_setprocattr,
5606
5607 .secid_to_secctx = selinux_secid_to_secctx,
5608 .secctx_to_secid = selinux_secctx_to_secid,
5609 .release_secctx = selinux_release_secctx,
5610 .inode_notifysecctx = selinux_inode_notifysecctx,
5611 .inode_setsecctx = selinux_inode_setsecctx,
5612 .inode_getsecctx = selinux_inode_getsecctx,
5613
5614 .unix_stream_connect = selinux_socket_unix_stream_connect,
5615 .unix_may_send = selinux_socket_unix_may_send,
5616
5617 .socket_create = selinux_socket_create,
5618 .socket_post_create = selinux_socket_post_create,
5619 .socket_bind = selinux_socket_bind,
5620 .socket_connect = selinux_socket_connect,
5621 .socket_listen = selinux_socket_listen,
5622 .socket_accept = selinux_socket_accept,
5623 .socket_sendmsg = selinux_socket_sendmsg,
5624 .socket_recvmsg = selinux_socket_recvmsg,
5625 .socket_getsockname = selinux_socket_getsockname,
5626 .socket_getpeername = selinux_socket_getpeername,
5627 .socket_getsockopt = selinux_socket_getsockopt,
5628 .socket_setsockopt = selinux_socket_setsockopt,
5629 .socket_shutdown = selinux_socket_shutdown,
5630 .socket_sock_rcv_skb = selinux_socket_sock_rcv_skb,
5631 .socket_getpeersec_stream = selinux_socket_getpeersec_stream,
5632 .socket_getpeersec_dgram = selinux_socket_getpeersec_dgram,
5633 .sk_alloc_security = selinux_sk_alloc_security,
5634 .sk_free_security = selinux_sk_free_security,
5635 .sk_clone_security = selinux_sk_clone_security,
5636 .sk_getsecid = selinux_sk_getsecid,
5637 .sock_graft = selinux_sock_graft,
5638 .inet_conn_request = selinux_inet_conn_request,
5639 .inet_csk_clone = selinux_inet_csk_clone,
5640 .inet_conn_established = selinux_inet_conn_established,
5641 .secmark_relabel_packet = selinux_secmark_relabel_packet,
5642 .secmark_refcount_inc = selinux_secmark_refcount_inc,
5643 .secmark_refcount_dec = selinux_secmark_refcount_dec,
5644 .req_classify_flow = selinux_req_classify_flow,
5645 .tun_dev_create = selinux_tun_dev_create,
5646 .tun_dev_post_create = selinux_tun_dev_post_create,
5647 .tun_dev_attach = selinux_tun_dev_attach,
5648
5649 #ifdef CONFIG_SECURITY_NETWORK_XFRM
5650 .xfrm_policy_alloc_security = selinux_xfrm_policy_alloc,
5651 .xfrm_policy_clone_security = selinux_xfrm_policy_clone,
5652 .xfrm_policy_free_security = selinux_xfrm_policy_free,
5653 .xfrm_policy_delete_security = selinux_xfrm_policy_delete,
5654 .xfrm_state_alloc_security = selinux_xfrm_state_alloc,
5655 .xfrm_state_free_security = selinux_xfrm_state_free,
5656 .xfrm_state_delete_security = selinux_xfrm_state_delete,
5657 .xfrm_policy_lookup = selinux_xfrm_policy_lookup,
5658 .xfrm_state_pol_flow_match = selinux_xfrm_state_pol_flow_match,
5659 .xfrm_decode_session = selinux_xfrm_decode_session,
5660 #endif
5661
5662 #ifdef CONFIG_KEYS
5663 .key_alloc = selinux_key_alloc,
5664 .key_free = selinux_key_free,
5665 .key_permission = selinux_key_permission,
5666 .key_getsecurity = selinux_key_getsecurity,
5667 #endif
5668
5669 #ifdef CONFIG_AUDIT
5670 .audit_rule_init = selinux_audit_rule_init,
5671 .audit_rule_known = selinux_audit_rule_known,
5672 .audit_rule_match = selinux_audit_rule_match,
5673 .audit_rule_free = selinux_audit_rule_free,
5674 #endif
5675 };
5676
5677 static __init int selinux_init(void)
5678 {
5679 if (!security_module_enable(&selinux_ops)) {
5680 selinux_enabled = 0;
5681 return 0;
5682 }
5683
5684 if (!selinux_enabled) {
5685 printk(KERN_INFO "SELinux: Disabled at boot.\n");
5686 return 0;
5687 }
5688
5689 printk(KERN_INFO "SELinux: Initializing.\n");
5690
5691 /* Set the security state for the initial task. */
5692 cred_init_security();
5693
5694 default_noexec = !(VM_DATA_DEFAULT_FLAGS & VM_EXEC);
5695
5696 sel_inode_cache = kmem_cache_create("selinux_inode_security",
5697 sizeof(struct inode_security_struct),
5698 0, SLAB_PANIC, NULL);
5699 avc_init();
5700
5701 if (register_security(&selinux_ops))
5702 panic("SELinux: Unable to register with kernel.\n");
5703
5704 if (selinux_enforcing)
5705 printk(KERN_DEBUG "SELinux: Starting in enforcing mode\n");
5706 else
5707 printk(KERN_DEBUG "SELinux: Starting in permissive mode\n");
5708
5709 return 0;
5710 }
5711
5712 static void delayed_superblock_init(struct super_block *sb, void *unused)
5713 {
5714 superblock_doinit(sb, NULL);
5715 }
5716
5717 void selinux_complete_init(void)
5718 {
5719 printk(KERN_DEBUG "SELinux: Completing initialization.\n");
5720
5721 /* Set up any superblocks initialized prior to the policy load. */
5722 printk(KERN_DEBUG "SELinux: Setting up existing superblocks.\n");
5723 iterate_supers(delayed_superblock_init, NULL);
5724 }
5725
5726 /* SELinux requires early initialization in order to label
5727 all processes and objects when they are created. */
5728 security_initcall(selinux_init);
5729
5730 #if defined(CONFIG_NETFILTER)
5731
5732 static struct nf_hook_ops selinux_ipv4_ops[] = {
5733 {
5734 .hook = selinux_ipv4_postroute,
5735 .owner = THIS_MODULE,
5736 .pf = NFPROTO_IPV4,
5737 .hooknum = NF_INET_POST_ROUTING,
5738 .priority = NF_IP_PRI_SELINUX_LAST,
5739 },
5740 {
5741 .hook = selinux_ipv4_forward,
5742 .owner = THIS_MODULE,
5743 .pf = NFPROTO_IPV4,
5744 .hooknum = NF_INET_FORWARD,
5745 .priority = NF_IP_PRI_SELINUX_FIRST,
5746 },
5747 {
5748 .hook = selinux_ipv4_output,
5749 .owner = THIS_MODULE,
5750 .pf = NFPROTO_IPV4,
5751 .hooknum = NF_INET_LOCAL_OUT,
5752 .priority = NF_IP_PRI_SELINUX_FIRST,
5753 }
5754 };
5755
5756 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
5757
5758 static struct nf_hook_ops selinux_ipv6_ops[] = {
5759 {
5760 .hook = selinux_ipv6_postroute,
5761 .owner = THIS_MODULE,
5762 .pf = NFPROTO_IPV6,
5763 .hooknum = NF_INET_POST_ROUTING,
5764 .priority = NF_IP6_PRI_SELINUX_LAST,
5765 },
5766 {
5767 .hook = selinux_ipv6_forward,
5768 .owner = THIS_MODULE,
5769 .pf = NFPROTO_IPV6,
5770 .hooknum = NF_INET_FORWARD,
5771 .priority = NF_IP6_PRI_SELINUX_FIRST,
5772 }
5773 };
5774
5775 #endif /* IPV6 */
5776
5777 static int __init selinux_nf_ip_init(void)
5778 {
5779 int err = 0;
5780
5781 if (!selinux_enabled)
5782 goto out;
5783
5784 printk(KERN_DEBUG "SELinux: Registering netfilter hooks\n");
5785
5786 err = nf_register_hooks(selinux_ipv4_ops, ARRAY_SIZE(selinux_ipv4_ops));
5787 if (err)
5788 panic("SELinux: nf_register_hooks for IPv4: error %d\n", err);
5789
5790 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
5791 err = nf_register_hooks(selinux_ipv6_ops, ARRAY_SIZE(selinux_ipv6_ops));
5792 if (err)
5793 panic("SELinux: nf_register_hooks for IPv6: error %d\n", err);
5794 #endif /* IPV6 */
5795
5796 out:
5797 return err;
5798 }
5799
5800 __initcall(selinux_nf_ip_init);
5801
5802 #ifdef CONFIG_SECURITY_SELINUX_DISABLE
5803 static void selinux_nf_ip_exit(void)
5804 {
5805 printk(KERN_DEBUG "SELinux: Unregistering netfilter hooks\n");
5806
5807 nf_unregister_hooks(selinux_ipv4_ops, ARRAY_SIZE(selinux_ipv4_ops));
5808 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
5809 nf_unregister_hooks(selinux_ipv6_ops, ARRAY_SIZE(selinux_ipv6_ops));
5810 #endif /* IPV6 */
5811 }
5812 #endif
5813
5814 #else /* CONFIG_NETFILTER */
5815
5816 #ifdef CONFIG_SECURITY_SELINUX_DISABLE
5817 #define selinux_nf_ip_exit()
5818 #endif
5819
5820 #endif /* CONFIG_NETFILTER */
5821
5822 #ifdef CONFIG_SECURITY_SELINUX_DISABLE
5823 static int selinux_disabled;
5824
5825 int selinux_disable(void)
5826 {
5827 if (ss_initialized) {
5828 /* Not permitted after initial policy load. */
5829 return -EINVAL;
5830 }
5831
5832 if (selinux_disabled) {
5833 /* Only do this once. */
5834 return -EINVAL;
5835 }
5836
5837 printk(KERN_INFO "SELinux: Disabled at runtime.\n");
5838
5839 selinux_disabled = 1;
5840 selinux_enabled = 0;
5841
5842 reset_security_ops();
5843
5844 /* Try to destroy the avc node cache */
5845 avc_disable();
5846
5847 /* Unregister netfilter hooks. */
5848 selinux_nf_ip_exit();
5849
5850 /* Unregister selinuxfs. */
5851 exit_sel_fs();
5852
5853 return 0;
5854 }
5855 #endif
Linux kernel - Deliverables
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