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workqueue: use mod_delayed_work() instead of cancel + queue
[linux-2.6/libata-dev.git] / security / selinux / hooks.c
blob6c77f63c759198ead061712fb3bad1166c4ace2a
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->f_path.dentry->d_inode;
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 = bprm->file->f_path.dentry->d_inode;
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 /* Derived from fs/exec.c:flush_old_files. */
2092 static inline void flush_unauthorized_files(const struct cred *cred,
2093 struct files_struct *files)
2094 {
2095 struct file *file, *devnull = NULL;
2096 struct tty_struct *tty;
2097 struct fdtable *fdt;
2098 long j = -1;
2099 int drop_tty = 0;
2100
2101 tty = get_current_tty();
2102 if (tty) {
2103 spin_lock(&tty_files_lock);
2104 if (!list_empty(&tty->tty_files)) {
2105 struct tty_file_private *file_priv;
2106
2107 /* Revalidate access to controlling tty.
2108 Use path_has_perm on the tty path directly rather
2109 than using file_has_perm, as this particular open
2110 file may belong to another process and we are only
2111 interested in the inode-based check here. */
2112 file_priv = list_first_entry(&tty->tty_files,
2113 struct tty_file_private, list);
2114 file = file_priv->file;
2115 if (path_has_perm(cred, &file->f_path, FILE__READ | FILE__WRITE))
2116 drop_tty = 1;
2117 }
2118 spin_unlock(&tty_files_lock);
2119 tty_kref_put(tty);
2120 }
2121 /* Reset controlling tty. */
2122 if (drop_tty)
2123 no_tty();
2124
2125 /* Revalidate access to inherited open files. */
2126 spin_lock(&files->file_lock);
2127 for (;;) {
2128 unsigned long set, i;
2129 int fd;
2130
2131 j++;
2132 i = j * BITS_PER_LONG;
2133 fdt = files_fdtable(files);
2134 if (i >= fdt->max_fds)
2135 break;
2136 set = fdt->open_fds[j];
2137 if (!set)
2138 continue;
2139 spin_unlock(&files->file_lock);
2140 for ( ; set ; i++, set >>= 1) {
2141 if (set & 1) {
2142 file = fget(i);
2143 if (!file)
2144 continue;
2145 if (file_has_perm(cred,
2146 file,
2147 file_to_av(file))) {
2148 sys_close(i);
2149 fd = get_unused_fd();
2150 if (fd != i) {
2151 if (fd >= 0)
2152 put_unused_fd(fd);
2153 fput(file);
2154 continue;
2155 }
2156 if (devnull) {
2157 get_file(devnull);
2158 } else {
2159 devnull = dentry_open(
2160 &selinux_null,
2161 O_RDWR, cred);
2162 if (IS_ERR(devnull)) {
2163 devnull = NULL;
2164 put_unused_fd(fd);
2165 fput(file);
2166 continue;
2167 }
2168 }
2169 fd_install(fd, devnull);
2170 }
2171 fput(file);
2172 }
2173 }
2174 spin_lock(&files->file_lock);
2175
2176 }
2177 spin_unlock(&files->file_lock);
2178 }
2179
2180 /*
2181 * Prepare a process for imminent new credential changes due to exec
2182 */
2183 static void selinux_bprm_committing_creds(struct linux_binprm *bprm)
2184 {
2185 struct task_security_struct *new_tsec;
2186 struct rlimit *rlim, *initrlim;
2187 int rc, i;
2188
2189 new_tsec = bprm->cred->security;
2190 if (new_tsec->sid == new_tsec->osid)
2191 return;
2192
2193 /* Close files for which the new task SID is not authorized. */
2194 flush_unauthorized_files(bprm->cred, current->files);
2195
2196 /* Always clear parent death signal on SID transitions. */
2197 current->pdeath_signal = 0;
2198
2199 /* Check whether the new SID can inherit resource limits from the old
2200 * SID. If not, reset all soft limits to the lower of the current
2201 * task's hard limit and the init task's soft limit.
2202 *
2203 * Note that the setting of hard limits (even to lower them) can be
2204 * controlled by the setrlimit check. The inclusion of the init task's
2205 * soft limit into the computation is to avoid resetting soft limits
2206 * higher than the default soft limit for cases where the default is
2207 * lower than the hard limit, e.g. RLIMIT_CORE or RLIMIT_STACK.
2208 */
2209 rc = avc_has_perm(new_tsec->osid, new_tsec->sid, SECCLASS_PROCESS,
2210 PROCESS__RLIMITINH, NULL);
2211 if (rc) {
2212 /* protect against do_prlimit() */
2213 task_lock(current);
2214 for (i = 0; i < RLIM_NLIMITS; i++) {
2215 rlim = current->signal->rlim + i;
2216 initrlim = init_task.signal->rlim + i;
2217 rlim->rlim_cur = min(rlim->rlim_max, initrlim->rlim_cur);
2218 }
2219 task_unlock(current);
2220 update_rlimit_cpu(current, rlimit(RLIMIT_CPU));
2221 }
2222 }
2223
2224 /*
2225 * Clean up the process immediately after the installation of new credentials
2226 * due to exec
2227 */
2228 static void selinux_bprm_committed_creds(struct linux_binprm *bprm)
2229 {
2230 const struct task_security_struct *tsec = current_security();
2231 struct itimerval itimer;
2232 u32 osid, sid;
2233 int rc, i;
2234
2235 osid = tsec->osid;
2236 sid = tsec->sid;
2237
2238 if (sid == osid)
2239 return;
2240
2241 /* Check whether the new SID can inherit signal state from the old SID.
2242 * If not, clear itimers to avoid subsequent signal generation and
2243 * flush and unblock signals.
2244 *
2245 * This must occur _after_ the task SID has been updated so that any
2246 * kill done after the flush will be checked against the new SID.
2247 */
2248 rc = avc_has_perm(osid, sid, SECCLASS_PROCESS, PROCESS__SIGINH, NULL);
2249 if (rc) {
2250 memset(&itimer, 0, sizeof itimer);
2251 for (i = 0; i < 3; i++)
2252 do_setitimer(i, &itimer, NULL);
2253 spin_lock_irq(&current->sighand->siglock);
2254 if (!(current->signal->flags & SIGNAL_GROUP_EXIT)) {
2255 __flush_signals(current);
2256 flush_signal_handlers(current, 1);
2257 sigemptyset(&current->blocked);
2258 }
2259 spin_unlock_irq(&current->sighand->siglock);
2260 }
2261
2262 /* Wake up the parent if it is waiting so that it can recheck
2263 * wait permission to the new task SID. */
2264 read_lock(&tasklist_lock);
2265 __wake_up_parent(current, current->real_parent);
2266 read_unlock(&tasklist_lock);
2267 }
2268
2269 /* superblock security operations */
2270
2271 static int selinux_sb_alloc_security(struct super_block *sb)
2272 {
2273 return superblock_alloc_security(sb);
2274 }
2275
2276 static void selinux_sb_free_security(struct super_block *sb)
2277 {
2278 superblock_free_security(sb);
2279 }
2280
2281 static inline int match_prefix(char *prefix, int plen, char *option, int olen)
2282 {
2283 if (plen > olen)
2284 return 0;
2285
2286 return !memcmp(prefix, option, plen);
2287 }
2288
2289 static inline int selinux_option(char *option, int len)
2290 {
2291 return (match_prefix(CONTEXT_STR, sizeof(CONTEXT_STR)-1, option, len) ||
2292 match_prefix(FSCONTEXT_STR, sizeof(FSCONTEXT_STR)-1, option, len) ||
2293 match_prefix(DEFCONTEXT_STR, sizeof(DEFCONTEXT_STR)-1, option, len) ||
2294 match_prefix(ROOTCONTEXT_STR, sizeof(ROOTCONTEXT_STR)-1, option, len) ||
2295 match_prefix(LABELSUPP_STR, sizeof(LABELSUPP_STR)-1, option, len));
2296 }
2297
2298 static inline void take_option(char **to, char *from, int *first, int len)
2299 {
2300 if (!*first) {
2301 **to = ',';
2302 *to += 1;
2303 } else
2304 *first = 0;
2305 memcpy(*to, from, len);
2306 *to += len;
2307 }
2308
2309 static inline void take_selinux_option(char **to, char *from, int *first,
2310 int len)
2311 {
2312 int current_size = 0;
2313
2314 if (!*first) {
2315 **to = '|';
2316 *to += 1;
2317 } else
2318 *first = 0;
2319
2320 while (current_size < len) {
2321 if (*from != '"') {
2322 **to = *from;
2323 *to += 1;
2324 }
2325 from += 1;
2326 current_size += 1;
2327 }
2328 }
2329
2330 static int selinux_sb_copy_data(char *orig, char *copy)
2331 {
2332 int fnosec, fsec, rc = 0;
2333 char *in_save, *in_curr, *in_end;
2334 char *sec_curr, *nosec_save, *nosec;
2335 int open_quote = 0;
2336
2337 in_curr = orig;
2338 sec_curr = copy;
2339
2340 nosec = (char *)get_zeroed_page(GFP_KERNEL);
2341 if (!nosec) {
2342 rc = -ENOMEM;
2343 goto out;
2344 }
2345
2346 nosec_save = nosec;
2347 fnosec = fsec = 1;
2348 in_save = in_end = orig;
2349
2350 do {
2351 if (*in_end == '"')
2352 open_quote = !open_quote;
2353 if ((*in_end == ',' && open_quote == 0) ||
2354 *in_end == '\0') {
2355 int len = in_end - in_curr;
2356
2357 if (selinux_option(in_curr, len))
2358 take_selinux_option(&sec_curr, in_curr, &fsec, len);
2359 else
2360 take_option(&nosec, in_curr, &fnosec, len);
2361
2362 in_curr = in_end + 1;
2363 }
2364 } while (*in_end++);
2365
2366 strcpy(in_save, nosec_save);
2367 free_page((unsigned long)nosec_save);
2368 out:
2369 return rc;
2370 }
2371
2372 static int selinux_sb_remount(struct super_block *sb, void *data)
2373 {
2374 int rc, i, *flags;
2375 struct security_mnt_opts opts;
2376 char *secdata, **mount_options;
2377 struct superblock_security_struct *sbsec = sb->s_security;
2378
2379 if (!(sbsec->flags & SE_SBINITIALIZED))
2380 return 0;
2381
2382 if (!data)
2383 return 0;
2384
2385 if (sb->s_type->fs_flags & FS_BINARY_MOUNTDATA)
2386 return 0;
2387
2388 security_init_mnt_opts(&opts);
2389 secdata = alloc_secdata();
2390 if (!secdata)
2391 return -ENOMEM;
2392 rc = selinux_sb_copy_data(data, secdata);
2393 if (rc)
2394 goto out_free_secdata;
2395
2396 rc = selinux_parse_opts_str(secdata, &opts);
2397 if (rc)
2398 goto out_free_secdata;
2399
2400 mount_options = opts.mnt_opts;
2401 flags = opts.mnt_opts_flags;
2402
2403 for (i = 0; i < opts.num_mnt_opts; i++) {
2404 u32 sid;
2405 size_t len;
2406
2407 if (flags[i] == SE_SBLABELSUPP)
2408 continue;
2409 len = strlen(mount_options[i]);
2410 rc = security_context_to_sid(mount_options[i], len, &sid);
2411 if (rc) {
2412 printk(KERN_WARNING "SELinux: security_context_to_sid"
2413 "(%s) failed for (dev %s, type %s) errno=%d\n",
2414 mount_options[i], sb->s_id, sb->s_type->name, rc);
2415 goto out_free_opts;
2416 }
2417 rc = -EINVAL;
2418 switch (flags[i]) {
2419 case FSCONTEXT_MNT:
2420 if (bad_option(sbsec, FSCONTEXT_MNT, sbsec->sid, sid))
2421 goto out_bad_option;
2422 break;
2423 case CONTEXT_MNT:
2424 if (bad_option(sbsec, CONTEXT_MNT, sbsec->mntpoint_sid, sid))
2425 goto out_bad_option;
2426 break;
2427 case ROOTCONTEXT_MNT: {
2428 struct inode_security_struct *root_isec;
2429 root_isec = sb->s_root->d_inode->i_security;
2430
2431 if (bad_option(sbsec, ROOTCONTEXT_MNT, root_isec->sid, sid))
2432 goto out_bad_option;
2433 break;
2434 }
2435 case DEFCONTEXT_MNT:
2436 if (bad_option(sbsec, DEFCONTEXT_MNT, sbsec->def_sid, sid))
2437 goto out_bad_option;
2438 break;
2439 default:
2440 goto out_free_opts;
2441 }
2442 }
2443
2444 rc = 0;
2445 out_free_opts:
2446 security_free_mnt_opts(&opts);
2447 out_free_secdata:
2448 free_secdata(secdata);
2449 return rc;
2450 out_bad_option:
2451 printk(KERN_WARNING "SELinux: unable to change security options "
2452 "during remount (dev %s, type=%s)\n", sb->s_id,
2453 sb->s_type->name);
2454 goto out_free_opts;
2455 }
2456
2457 static int selinux_sb_kern_mount(struct super_block *sb, int flags, void *data)
2458 {
2459 const struct cred *cred = current_cred();
2460 struct common_audit_data ad;
2461 int rc;
2462
2463 rc = superblock_doinit(sb, data);
2464 if (rc)
2465 return rc;
2466
2467 /* Allow all mounts performed by the kernel */
2468 if (flags & MS_KERNMOUNT)
2469 return 0;
2470
2471 ad.type = LSM_AUDIT_DATA_DENTRY;
2472 ad.u.dentry = sb->s_root;
2473 return superblock_has_perm(cred, sb, FILESYSTEM__MOUNT, &ad);
2474 }
2475
2476 static int selinux_sb_statfs(struct dentry *dentry)
2477 {
2478 const struct cred *cred = current_cred();
2479 struct common_audit_data ad;
2480
2481 ad.type = LSM_AUDIT_DATA_DENTRY;
2482 ad.u.dentry = dentry->d_sb->s_root;
2483 return superblock_has_perm(cred, dentry->d_sb, FILESYSTEM__GETATTR, &ad);
2484 }
2485
2486 static int selinux_mount(char *dev_name,
2487 struct path *path,
2488 char *type,
2489 unsigned long flags,
2490 void *data)
2491 {
2492 const struct cred *cred = current_cred();
2493
2494 if (flags & MS_REMOUNT)
2495 return superblock_has_perm(cred, path->dentry->d_sb,
2496 FILESYSTEM__REMOUNT, NULL);
2497 else
2498 return path_has_perm(cred, path, FILE__MOUNTON);
2499 }
2500
2501 static int selinux_umount(struct vfsmount *mnt, int flags)
2502 {
2503 const struct cred *cred = current_cred();
2504
2505 return superblock_has_perm(cred, mnt->mnt_sb,
2506 FILESYSTEM__UNMOUNT, NULL);
2507 }
2508
2509 /* inode security operations */
2510
2511 static int selinux_inode_alloc_security(struct inode *inode)
2512 {
2513 return inode_alloc_security(inode);
2514 }
2515
2516 static void selinux_inode_free_security(struct inode *inode)
2517 {
2518 inode_free_security(inode);
2519 }
2520
2521 static int selinux_inode_init_security(struct inode *inode, struct inode *dir,
2522 const struct qstr *qstr, char **name,
2523 void **value, size_t *len)
2524 {
2525 const struct task_security_struct *tsec = current_security();
2526 struct inode_security_struct *dsec;
2527 struct superblock_security_struct *sbsec;
2528 u32 sid, newsid, clen;
2529 int rc;
2530 char *namep = NULL, *context;
2531
2532 dsec = dir->i_security;
2533 sbsec = dir->i_sb->s_security;
2534
2535 sid = tsec->sid;
2536 newsid = tsec->create_sid;
2537
2538 if ((sbsec->flags & SE_SBINITIALIZED) &&
2539 (sbsec->behavior == SECURITY_FS_USE_MNTPOINT))
2540 newsid = sbsec->mntpoint_sid;
2541 else if (!newsid || !(sbsec->flags & SE_SBLABELSUPP)) {
2542 rc = security_transition_sid(sid, dsec->sid,
2543 inode_mode_to_security_class(inode->i_mode),
2544 qstr, &newsid);
2545 if (rc) {
2546 printk(KERN_WARNING "%s: "
2547 "security_transition_sid failed, rc=%d (dev=%s "
2548 "ino=%ld)\n",
2549 __func__,
2550 -rc, inode->i_sb->s_id, inode->i_ino);
2551 return rc;
2552 }
2553 }
2554
2555 /* Possibly defer initialization to selinux_complete_init. */
2556 if (sbsec->flags & SE_SBINITIALIZED) {
2557 struct inode_security_struct *isec = inode->i_security;
2558 isec->sclass = inode_mode_to_security_class(inode->i_mode);
2559 isec->sid = newsid;
2560 isec->initialized = 1;
2561 }
2562
2563 if (!ss_initialized || !(sbsec->flags & SE_SBLABELSUPP))
2564 return -EOPNOTSUPP;
2565
2566 if (name) {
2567 namep = kstrdup(XATTR_SELINUX_SUFFIX, GFP_NOFS);
2568 if (!namep)
2569 return -ENOMEM;
2570 *name = namep;
2571 }
2572
2573 if (value && len) {
2574 rc = security_sid_to_context_force(newsid, &context, &clen);
2575 if (rc) {
2576 kfree(namep);
2577 return rc;
2578 }
2579 *value = context;
2580 *len = clen;
2581 }
2582
2583 return 0;
2584 }
2585
2586 static int selinux_inode_create(struct inode *dir, struct dentry *dentry, umode_t mode)
2587 {
2588 return may_create(dir, dentry, SECCLASS_FILE);
2589 }
2590
2591 static int selinux_inode_link(struct dentry *old_dentry, struct inode *dir, struct dentry *new_dentry)
2592 {
2593 return may_link(dir, old_dentry, MAY_LINK);
2594 }
2595
2596 static int selinux_inode_unlink(struct inode *dir, struct dentry *dentry)
2597 {
2598 return may_link(dir, dentry, MAY_UNLINK);
2599 }
2600
2601 static int selinux_inode_symlink(struct inode *dir, struct dentry *dentry, const char *name)
2602 {
2603 return may_create(dir, dentry, SECCLASS_LNK_FILE);
2604 }
2605
2606 static int selinux_inode_mkdir(struct inode *dir, struct dentry *dentry, umode_t mask)
2607 {
2608 return may_create(dir, dentry, SECCLASS_DIR);
2609 }
2610
2611 static int selinux_inode_rmdir(struct inode *dir, struct dentry *dentry)
2612 {
2613 return may_link(dir, dentry, MAY_RMDIR);
2614 }
2615
2616 static int selinux_inode_mknod(struct inode *dir, struct dentry *dentry, umode_t mode, dev_t dev)
2617 {
2618 return may_create(dir, dentry, inode_mode_to_security_class(mode));
2619 }
2620
2621 static int selinux_inode_rename(struct inode *old_inode, struct dentry *old_dentry,
2622 struct inode *new_inode, struct dentry *new_dentry)
2623 {
2624 return may_rename(old_inode, old_dentry, new_inode, new_dentry);
2625 }
2626
2627 static int selinux_inode_readlink(struct dentry *dentry)
2628 {
2629 const struct cred *cred = current_cred();
2630
2631 return dentry_has_perm(cred, dentry, FILE__READ);
2632 }
2633
2634 static int selinux_inode_follow_link(struct dentry *dentry, struct nameidata *nameidata)
2635 {
2636 const struct cred *cred = current_cred();
2637
2638 return dentry_has_perm(cred, dentry, FILE__READ);
2639 }
2640
2641 static noinline int audit_inode_permission(struct inode *inode,
2642 u32 perms, u32 audited, u32 denied,
2643 unsigned flags)
2644 {
2645 struct common_audit_data ad;
2646 struct inode_security_struct *isec = inode->i_security;
2647 int rc;
2648
2649 ad.type = LSM_AUDIT_DATA_INODE;
2650 ad.u.inode = inode;
2651
2652 rc = slow_avc_audit(current_sid(), isec->sid, isec->sclass, perms,
2653 audited, denied, &ad, flags);
2654 if (rc)
2655 return rc;
2656 return 0;
2657 }
2658
2659 static int selinux_inode_permission(struct inode *inode, int mask)
2660 {
2661 const struct cred *cred = current_cred();
2662 u32 perms;
2663 bool from_access;
2664 unsigned flags = mask & MAY_NOT_BLOCK;
2665 struct inode_security_struct *isec;
2666 u32 sid;
2667 struct av_decision avd;
2668 int rc, rc2;
2669 u32 audited, denied;
2670
2671 from_access = mask & MAY_ACCESS;
2672 mask &= (MAY_READ|MAY_WRITE|MAY_EXEC|MAY_APPEND);
2673
2674 /* No permission to check. Existence test. */
2675 if (!mask)
2676 return 0;
2677
2678 validate_creds(cred);
2679
2680 if (unlikely(IS_PRIVATE(inode)))
2681 return 0;
2682
2683 perms = file_mask_to_av(inode->i_mode, mask);
2684
2685 sid = cred_sid(cred);
2686 isec = inode->i_security;
2687
2688 rc = avc_has_perm_noaudit(sid, isec->sid, isec->sclass, perms, 0, &avd);
2689 audited = avc_audit_required(perms, &avd, rc,
2690 from_access ? FILE__AUDIT_ACCESS : 0,
2691 &denied);
2692 if (likely(!audited))
2693 return rc;
2694
2695 rc2 = audit_inode_permission(inode, perms, audited, denied, flags);
2696 if (rc2)
2697 return rc2;
2698 return rc;
2699 }
2700
2701 static int selinux_inode_setattr(struct dentry *dentry, struct iattr *iattr)
2702 {
2703 const struct cred *cred = current_cred();
2704 unsigned int ia_valid = iattr->ia_valid;
2705 __u32 av = FILE__WRITE;
2706
2707 /* ATTR_FORCE is just used for ATTR_KILL_S[UG]ID. */
2708 if (ia_valid & ATTR_FORCE) {
2709 ia_valid &= ~(ATTR_KILL_SUID | ATTR_KILL_SGID | ATTR_MODE |
2710 ATTR_FORCE);
2711 if (!ia_valid)
2712 return 0;
2713 }
2714
2715 if (ia_valid & (ATTR_MODE | ATTR_UID | ATTR_GID |
2716 ATTR_ATIME_SET | ATTR_MTIME_SET | ATTR_TIMES_SET))
2717 return dentry_has_perm(cred, dentry, FILE__SETATTR);
2718
2719 if (selinux_policycap_openperm && (ia_valid & ATTR_SIZE))
2720 av |= FILE__OPEN;
2721
2722 return dentry_has_perm(cred, dentry, av);
2723 }
2724
2725 static int selinux_inode_getattr(struct vfsmount *mnt, struct dentry *dentry)
2726 {
2727 const struct cred *cred = current_cred();
2728 struct path path;
2729
2730 path.dentry = dentry;
2731 path.mnt = mnt;
2732
2733 return path_has_perm(cred, &path, FILE__GETATTR);
2734 }
2735
2736 static int selinux_inode_setotherxattr(struct dentry *dentry, const char *name)
2737 {
2738 const struct cred *cred = current_cred();
2739
2740 if (!strncmp(name, XATTR_SECURITY_PREFIX,
2741 sizeof XATTR_SECURITY_PREFIX - 1)) {
2742 if (!strcmp(name, XATTR_NAME_CAPS)) {
2743 if (!capable(CAP_SETFCAP))
2744 return -EPERM;
2745 } else if (!capable(CAP_SYS_ADMIN)) {
2746 /* A different attribute in the security namespace.
2747 Restrict to administrator. */
2748 return -EPERM;
2749 }
2750 }
2751
2752 /* Not an attribute we recognize, so just check the
2753 ordinary setattr permission. */
2754 return dentry_has_perm(cred, dentry, FILE__SETATTR);
2755 }
2756
2757 static int selinux_inode_setxattr(struct dentry *dentry, const char *name,
2758 const void *value, size_t size, int flags)
2759 {
2760 struct inode *inode = dentry->d_inode;
2761 struct inode_security_struct *isec = inode->i_security;
2762 struct superblock_security_struct *sbsec;
2763 struct common_audit_data ad;
2764 u32 newsid, sid = current_sid();
2765 int rc = 0;
2766
2767 if (strcmp(name, XATTR_NAME_SELINUX))
2768 return selinux_inode_setotherxattr(dentry, name);
2769
2770 sbsec = inode->i_sb->s_security;
2771 if (!(sbsec->flags & SE_SBLABELSUPP))
2772 return -EOPNOTSUPP;
2773
2774 if (!inode_owner_or_capable(inode))
2775 return -EPERM;
2776
2777 ad.type = LSM_AUDIT_DATA_DENTRY;
2778 ad.u.dentry = dentry;
2779
2780 rc = avc_has_perm(sid, isec->sid, isec->sclass,
2781 FILE__RELABELFROM, &ad);
2782 if (rc)
2783 return rc;
2784
2785 rc = security_context_to_sid(value, size, &newsid);
2786 if (rc == -EINVAL) {
2787 if (!capable(CAP_MAC_ADMIN)) {
2788 struct audit_buffer *ab;
2789 size_t audit_size;
2790 const char *str;
2791
2792 /* We strip a nul only if it is at the end, otherwise the
2793 * context contains a nul and we should audit that */
2794 if (value) {
2795 str = value;
2796 if (str[size - 1] == '\0')
2797 audit_size = size - 1;
2798 else
2799 audit_size = size;
2800 } else {
2801 str = "";
2802 audit_size = 0;
2803 }
2804 ab = audit_log_start(current->audit_context, GFP_ATOMIC, AUDIT_SELINUX_ERR);
2805 audit_log_format(ab, "op=setxattr invalid_context=");
2806 audit_log_n_untrustedstring(ab, value, audit_size);
2807 audit_log_end(ab);
2808
2809 return rc;
2810 }
2811 rc = security_context_to_sid_force(value, size, &newsid);
2812 }
2813 if (rc)
2814 return rc;
2815
2816 rc = avc_has_perm(sid, newsid, isec->sclass,
2817 FILE__RELABELTO, &ad);
2818 if (rc)
2819 return rc;
2820
2821 rc = security_validate_transition(isec->sid, newsid, sid,
2822 isec->sclass);
2823 if (rc)
2824 return rc;
2825
2826 return avc_has_perm(newsid,
2827 sbsec->sid,
2828 SECCLASS_FILESYSTEM,
2829 FILESYSTEM__ASSOCIATE,
2830 &ad);
2831 }
2832
2833 static void selinux_inode_post_setxattr(struct dentry *dentry, const char *name,
2834 const void *value, size_t size,
2835 int flags)
2836 {
2837 struct inode *inode = dentry->d_inode;
2838 struct inode_security_struct *isec = inode->i_security;
2839 u32 newsid;
2840 int rc;
2841
2842 if (strcmp(name, XATTR_NAME_SELINUX)) {
2843 /* Not an attribute we recognize, so nothing to do. */
2844 return;
2845 }
2846
2847 rc = security_context_to_sid_force(value, size, &newsid);
2848 if (rc) {
2849 printk(KERN_ERR "SELinux: unable to map context to SID"
2850 "for (%s, %lu), rc=%d\n",
2851 inode->i_sb->s_id, inode->i_ino, -rc);
2852 return;
2853 }
2854
2855 isec->sid = newsid;
2856 return;
2857 }
2858
2859 static int selinux_inode_getxattr(struct dentry *dentry, const char *name)
2860 {
2861 const struct cred *cred = current_cred();
2862
2863 return dentry_has_perm(cred, dentry, FILE__GETATTR);
2864 }
2865
2866 static int selinux_inode_listxattr(struct dentry *dentry)
2867 {
2868 const struct cred *cred = current_cred();
2869
2870 return dentry_has_perm(cred, dentry, FILE__GETATTR);
2871 }
2872
2873 static int selinux_inode_removexattr(struct dentry *dentry, const char *name)
2874 {
2875 if (strcmp(name, XATTR_NAME_SELINUX))
2876 return selinux_inode_setotherxattr(dentry, name);
2877
2878 /* No one is allowed to remove a SELinux security label.
2879 You can change the label, but all data must be labeled. */
2880 return -EACCES;
2881 }
2882
2883 /*
2884 * Copy the inode security context value to the user.
2885 *
2886 * Permission check is handled by selinux_inode_getxattr hook.
2887 */
2888 static int selinux_inode_getsecurity(const struct inode *inode, const char *name, void **buffer, bool alloc)
2889 {
2890 u32 size;
2891 int error;
2892 char *context = NULL;
2893 struct inode_security_struct *isec = inode->i_security;
2894
2895 if (strcmp(name, XATTR_SELINUX_SUFFIX))
2896 return -EOPNOTSUPP;
2897
2898 /*
2899 * If the caller has CAP_MAC_ADMIN, then get the raw context
2900 * value even if it is not defined by current policy; otherwise,
2901 * use the in-core value under current policy.
2902 * Use the non-auditing forms of the permission checks since
2903 * getxattr may be called by unprivileged processes commonly
2904 * and lack of permission just means that we fall back to the
2905 * in-core context value, not a denial.
2906 */
2907 error = selinux_capable(current_cred(), &init_user_ns, CAP_MAC_ADMIN,
2908 SECURITY_CAP_NOAUDIT);
2909 if (!error)
2910 error = security_sid_to_context_force(isec->sid, &context,
2911 &size);
2912 else
2913 error = security_sid_to_context(isec->sid, &context, &size);
2914 if (error)
2915 return error;
2916 error = size;
2917 if (alloc) {
2918 *buffer = context;
2919 goto out_nofree;
2920 }
2921 kfree(context);
2922 out_nofree:
2923 return error;
2924 }
2925
2926 static int selinux_inode_setsecurity(struct inode *inode, const char *name,
2927 const void *value, size_t size, int flags)
2928 {
2929 struct inode_security_struct *isec = inode->i_security;
2930 u32 newsid;
2931 int rc;
2932
2933 if (strcmp(name, XATTR_SELINUX_SUFFIX))
2934 return -EOPNOTSUPP;
2935
2936 if (!value || !size)
2937 return -EACCES;
2938
2939 rc = security_context_to_sid((void *)value, size, &newsid);
2940 if (rc)
2941 return rc;
2942
2943 isec->sid = newsid;
2944 isec->initialized = 1;
2945 return 0;
2946 }
2947
2948 static int selinux_inode_listsecurity(struct inode *inode, char *buffer, size_t buffer_size)
2949 {
2950 const int len = sizeof(XATTR_NAME_SELINUX);
2951 if (buffer && len <= buffer_size)
2952 memcpy(buffer, XATTR_NAME_SELINUX, len);
2953 return len;
2954 }
2955
2956 static void selinux_inode_getsecid(const struct inode *inode, u32 *secid)
2957 {
2958 struct inode_security_struct *isec = inode->i_security;
2959 *secid = isec->sid;
2960 }
2961
2962 /* file security operations */
2963
2964 static int selinux_revalidate_file_permission(struct file *file, int mask)
2965 {
2966 const struct cred *cred = current_cred();
2967 struct inode *inode = file->f_path.dentry->d_inode;
2968
2969 /* file_mask_to_av won't add FILE__WRITE if MAY_APPEND is set */
2970 if ((file->f_flags & O_APPEND) && (mask & MAY_WRITE))
2971 mask |= MAY_APPEND;
2972
2973 return file_has_perm(cred, file,
2974 file_mask_to_av(inode->i_mode, mask));
2975 }
2976
2977 static int selinux_file_permission(struct file *file, int mask)
2978 {
2979 struct inode *inode = file->f_path.dentry->d_inode;
2980 struct file_security_struct *fsec = file->f_security;
2981 struct inode_security_struct *isec = inode->i_security;
2982 u32 sid = current_sid();
2983
2984 if (!mask)
2985 /* No permission to check. Existence test. */
2986 return 0;
2987
2988 if (sid == fsec->sid && fsec->isid == isec->sid &&
2989 fsec->pseqno == avc_policy_seqno())
2990 /* No change since file_open check. */
2991 return 0;
2992
2993 return selinux_revalidate_file_permission(file, mask);
2994 }
2995
2996 static int selinux_file_alloc_security(struct file *file)
2997 {
2998 return file_alloc_security(file);
2999 }
3000
3001 static void selinux_file_free_security(struct file *file)
3002 {
3003 file_free_security(file);
3004 }
3005
3006 static int selinux_file_ioctl(struct file *file, unsigned int cmd,
3007 unsigned long arg)
3008 {
3009 const struct cred *cred = current_cred();
3010 int error = 0;
3011
3012 switch (cmd) {
3013 case FIONREAD:
3014 /* fall through */
3015 case FIBMAP:
3016 /* fall through */
3017 case FIGETBSZ:
3018 /* fall through */
3019 case FS_IOC_GETFLAGS:
3020 /* fall through */
3021 case FS_IOC_GETVERSION:
3022 error = file_has_perm(cred, file, FILE__GETATTR);
3023 break;
3024
3025 case FS_IOC_SETFLAGS:
3026 /* fall through */
3027 case FS_IOC_SETVERSION:
3028 error = file_has_perm(cred, file, FILE__SETATTR);
3029 break;
3030
3031 /* sys_ioctl() checks */
3032 case FIONBIO:
3033 /* fall through */
3034 case FIOASYNC:
3035 error = file_has_perm(cred, file, 0);
3036 break;
3037
3038 case KDSKBENT:
3039 case KDSKBSENT:
3040 error = cred_has_capability(cred, CAP_SYS_TTY_CONFIG,
3041 SECURITY_CAP_AUDIT);
3042 break;
3043
3044 /* default case assumes that the command will go
3045 * to the file's ioctl() function.
3046 */
3047 default:
3048 error = file_has_perm(cred, file, FILE__IOCTL);
3049 }
3050 return error;
3051 }
3052
3053 static int default_noexec;
3054
3055 static int file_map_prot_check(struct file *file, unsigned long prot, int shared)
3056 {
3057 const struct cred *cred = current_cred();
3058 int rc = 0;
3059
3060 if (default_noexec &&
3061 (prot & PROT_EXEC) && (!file || (!shared && (prot & PROT_WRITE)))) {
3062 /*
3063 * We are making executable an anonymous mapping or a
3064 * private file mapping that will also be writable.
3065 * This has an additional check.
3066 */
3067 rc = cred_has_perm(cred, cred, PROCESS__EXECMEM);
3068 if (rc)
3069 goto error;
3070 }
3071
3072 if (file) {
3073 /* read access is always possible with a mapping */
3074 u32 av = FILE__READ;
3075
3076 /* write access only matters if the mapping is shared */
3077 if (shared && (prot & PROT_WRITE))
3078 av |= FILE__WRITE;
3079
3080 if (prot & PROT_EXEC)
3081 av |= FILE__EXECUTE;
3082
3083 return file_has_perm(cred, file, av);
3084 }
3085
3086 error:
3087 return rc;
3088 }
3089
3090 static int selinux_mmap_addr(unsigned long addr)
3091 {
3092 int rc = 0;
3093 u32 sid = current_sid();
3094
3095 /*
3096 * notice that we are intentionally putting the SELinux check before
3097 * the secondary cap_file_mmap check. This is such a likely attempt
3098 * at bad behaviour/exploit that we always want to get the AVC, even
3099 * if DAC would have also denied the operation.
3100 */
3101 if (addr < CONFIG_LSM_MMAP_MIN_ADDR) {
3102 rc = avc_has_perm(sid, sid, SECCLASS_MEMPROTECT,
3103 MEMPROTECT__MMAP_ZERO, NULL);
3104 if (rc)
3105 return rc;
3106 }
3107
3108 /* do DAC check on address space usage */
3109 return cap_mmap_addr(addr);
3110 }
3111
3112 static int selinux_mmap_file(struct file *file, unsigned long reqprot,
3113 unsigned long prot, unsigned long flags)
3114 {
3115 if (selinux_checkreqprot)
3116 prot = reqprot;
3117
3118 return file_map_prot_check(file, prot,
3119 (flags & MAP_TYPE) == MAP_SHARED);
3120 }
3121
3122 static int selinux_file_mprotect(struct vm_area_struct *vma,
3123 unsigned long reqprot,
3124 unsigned long prot)
3125 {
3126 const struct cred *cred = current_cred();
3127
3128 if (selinux_checkreqprot)
3129 prot = reqprot;
3130
3131 if (default_noexec &&
3132 (prot & PROT_EXEC) && !(vma->vm_flags & VM_EXEC)) {
3133 int rc = 0;
3134 if (vma->vm_start >= vma->vm_mm->start_brk &&
3135 vma->vm_end <= vma->vm_mm->brk) {
3136 rc = cred_has_perm(cred, cred, PROCESS__EXECHEAP);
3137 } else if (!vma->vm_file &&
3138 vma->vm_start <= vma->vm_mm->start_stack &&
3139 vma->vm_end >= vma->vm_mm->start_stack) {
3140 rc = current_has_perm(current, PROCESS__EXECSTACK);
3141 } else if (vma->vm_file && vma->anon_vma) {
3142 /*
3143 * We are making executable a file mapping that has
3144 * had some COW done. Since pages might have been
3145 * written, check ability to execute the possibly
3146 * modified content. This typically should only
3147 * occur for text relocations.
3148 */
3149 rc = file_has_perm(cred, vma->vm_file, FILE__EXECMOD);
3150 }
3151 if (rc)
3152 return rc;
3153 }
3154
3155 return file_map_prot_check(vma->vm_file, prot, vma->vm_flags&VM_SHARED);
3156 }
3157
3158 static int selinux_file_lock(struct file *file, unsigned int cmd)
3159 {
3160 const struct cred *cred = current_cred();
3161
3162 return file_has_perm(cred, file, FILE__LOCK);
3163 }
3164
3165 static int selinux_file_fcntl(struct file *file, unsigned int cmd,
3166 unsigned long arg)
3167 {
3168 const struct cred *cred = current_cred();
3169 int err = 0;
3170
3171 switch (cmd) {
3172 case F_SETFL:
3173 if (!file->f_path.dentry || !file->f_path.dentry->d_inode) {
3174 err = -EINVAL;
3175 break;
3176 }
3177
3178 if ((file->f_flags & O_APPEND) && !(arg & O_APPEND)) {
3179 err = file_has_perm(cred, file, FILE__WRITE);
3180 break;
3181 }
3182 /* fall through */
3183 case F_SETOWN:
3184 case F_SETSIG:
3185 case F_GETFL:
3186 case F_GETOWN:
3187 case F_GETSIG:
3188 case F_GETOWNER_UIDS:
3189 /* Just check FD__USE permission */
3190 err = file_has_perm(cred, file, 0);
3191 break;
3192 case F_GETLK:
3193 case F_SETLK:
3194 case F_SETLKW:
3195 #if BITS_PER_LONG == 32
3196 case F_GETLK64:
3197 case F_SETLK64:
3198 case F_SETLKW64:
3199 #endif
3200 if (!file->f_path.dentry || !file->f_path.dentry->d_inode) {
3201 err = -EINVAL;
3202 break;
3203 }
3204 err = file_has_perm(cred, file, FILE__LOCK);
3205 break;
3206 }
3207
3208 return err;
3209 }
3210
3211 static int selinux_file_set_fowner(struct file *file)
3212 {
3213 struct file_security_struct *fsec;
3214
3215 fsec = file->f_security;
3216 fsec->fown_sid = current_sid();
3217
3218 return 0;
3219 }
3220
3221 static int selinux_file_send_sigiotask(struct task_struct *tsk,
3222 struct fown_struct *fown, int signum)
3223 {
3224 struct file *file;
3225 u32 sid = task_sid(tsk);
3226 u32 perm;
3227 struct file_security_struct *fsec;
3228
3229 /* struct fown_struct is never outside the context of a struct file */
3230 file = container_of(fown, struct file, f_owner);
3231
3232 fsec = file->f_security;
3233
3234 if (!signum)
3235 perm = signal_to_av(SIGIO); /* as per send_sigio_to_task */
3236 else
3237 perm = signal_to_av(signum);
3238
3239 return avc_has_perm(fsec->fown_sid, sid,
3240 SECCLASS_PROCESS, perm, NULL);
3241 }
3242
3243 static int selinux_file_receive(struct file *file)
3244 {
3245 const struct cred *cred = current_cred();
3246
3247 return file_has_perm(cred, file, file_to_av(file));
3248 }
3249
3250 static int selinux_file_open(struct file *file, const struct cred *cred)
3251 {
3252 struct file_security_struct *fsec;
3253 struct inode_security_struct *isec;
3254
3255 fsec = file->f_security;
3256 isec = file->f_path.dentry->d_inode->i_security;
3257 /*
3258 * Save inode label and policy sequence number
3259 * at open-time so that selinux_file_permission
3260 * can determine whether revalidation is necessary.
3261 * Task label is already saved in the file security
3262 * struct as its SID.
3263 */
3264 fsec->isid = isec->sid;
3265 fsec->pseqno = avc_policy_seqno();
3266 /*
3267 * Since the inode label or policy seqno may have changed
3268 * between the selinux_inode_permission check and the saving
3269 * of state above, recheck that access is still permitted.
3270 * Otherwise, access might never be revalidated against the
3271 * new inode label or new policy.
3272 * This check is not redundant - do not remove.
3273 */
3274 return path_has_perm(cred, &file->f_path, open_file_to_av(file));
3275 }
3276
3277 /* task security operations */
3278
3279 static int selinux_task_create(unsigned long clone_flags)
3280 {
3281 return current_has_perm(current, PROCESS__FORK);
3282 }
3283
3284 /*
3285 * allocate the SELinux part of blank credentials
3286 */
3287 static int selinux_cred_alloc_blank(struct cred *cred, gfp_t gfp)
3288 {
3289 struct task_security_struct *tsec;
3290
3291 tsec = kzalloc(sizeof(struct task_security_struct), gfp);
3292 if (!tsec)
3293 return -ENOMEM;
3294
3295 cred->security = tsec;
3296 return 0;
3297 }
3298
3299 /*
3300 * detach and free the LSM part of a set of credentials
3301 */
3302 static void selinux_cred_free(struct cred *cred)
3303 {
3304 struct task_security_struct *tsec = cred->security;
3305
3306 /*
3307 * cred->security == NULL if security_cred_alloc_blank() or
3308 * security_prepare_creds() returned an error.
3309 */
3310 BUG_ON(cred->security && (unsigned long) cred->security < PAGE_SIZE);
3311 cred->security = (void *) 0x7UL;
3312 kfree(tsec);
3313 }
3314
3315 /*
3316 * prepare a new set of credentials for modification
3317 */
3318 static int selinux_cred_prepare(struct cred *new, const struct cred *old,
3319 gfp_t gfp)
3320 {
3321 const struct task_security_struct *old_tsec;
3322 struct task_security_struct *tsec;
3323
3324 old_tsec = old->security;
3325
3326 tsec = kmemdup(old_tsec, sizeof(struct task_security_struct), gfp);
3327 if (!tsec)
3328 return -ENOMEM;
3329
3330 new->security = tsec;
3331 return 0;
3332 }
3333
3334 /*
3335 * transfer the SELinux data to a blank set of creds
3336 */
3337 static void selinux_cred_transfer(struct cred *new, const struct cred *old)
3338 {
3339 const struct task_security_struct *old_tsec = old->security;
3340 struct task_security_struct *tsec = new->security;
3341
3342 *tsec = *old_tsec;
3343 }
3344
3345 /*
3346 * set the security data for a kernel service
3347 * - all the creation contexts are set to unlabelled
3348 */
3349 static int selinux_kernel_act_as(struct cred *new, u32 secid)
3350 {
3351 struct task_security_struct *tsec = new->security;
3352 u32 sid = current_sid();
3353 int ret;
3354
3355 ret = avc_has_perm(sid, secid,
3356 SECCLASS_KERNEL_SERVICE,
3357 KERNEL_SERVICE__USE_AS_OVERRIDE,
3358 NULL);
3359 if (ret == 0) {
3360 tsec->sid = secid;
3361 tsec->create_sid = 0;
3362 tsec->keycreate_sid = 0;
3363 tsec->sockcreate_sid = 0;
3364 }
3365 return ret;
3366 }
3367
3368 /*
3369 * set the file creation context in a security record to the same as the
3370 * objective context of the specified inode
3371 */
3372 static int selinux_kernel_create_files_as(struct cred *new, struct inode *inode)
3373 {
3374 struct inode_security_struct *isec = inode->i_security;
3375 struct task_security_struct *tsec = new->security;
3376 u32 sid = current_sid();
3377 int ret;
3378
3379 ret = avc_has_perm(sid, isec->sid,
3380 SECCLASS_KERNEL_SERVICE,
3381 KERNEL_SERVICE__CREATE_FILES_AS,
3382 NULL);
3383
3384 if (ret == 0)
3385 tsec->create_sid = isec->sid;
3386 return ret;
3387 }
3388
3389 static int selinux_kernel_module_request(char *kmod_name)
3390 {
3391 u32 sid;
3392 struct common_audit_data ad;
3393
3394 sid = task_sid(current);
3395
3396 ad.type = LSM_AUDIT_DATA_KMOD;
3397 ad.u.kmod_name = kmod_name;
3398
3399 return avc_has_perm(sid, SECINITSID_KERNEL, SECCLASS_SYSTEM,
3400 SYSTEM__MODULE_REQUEST, &ad);
3401 }
3402
3403 static int selinux_task_setpgid(struct task_struct *p, pid_t pgid)
3404 {
3405 return current_has_perm(p, PROCESS__SETPGID);
3406 }
3407
3408 static int selinux_task_getpgid(struct task_struct *p)
3409 {
3410 return current_has_perm(p, PROCESS__GETPGID);
3411 }
3412
3413 static int selinux_task_getsid(struct task_struct *p)
3414 {
3415 return current_has_perm(p, PROCESS__GETSESSION);
3416 }
3417
3418 static void selinux_task_getsecid(struct task_struct *p, u32 *secid)
3419 {
3420 *secid = task_sid(p);
3421 }
3422
3423 static int selinux_task_setnice(struct task_struct *p, int nice)
3424 {
3425 int rc;
3426
3427 rc = cap_task_setnice(p, nice);
3428 if (rc)
3429 return rc;
3430
3431 return current_has_perm(p, PROCESS__SETSCHED);
3432 }
3433
3434 static int selinux_task_setioprio(struct task_struct *p, int ioprio)
3435 {
3436 int rc;
3437
3438 rc = cap_task_setioprio(p, ioprio);
3439 if (rc)
3440 return rc;
3441
3442 return current_has_perm(p, PROCESS__SETSCHED);
3443 }
3444
3445 static int selinux_task_getioprio(struct task_struct *p)
3446 {
3447 return current_has_perm(p, PROCESS__GETSCHED);
3448 }
3449
3450 static int selinux_task_setrlimit(struct task_struct *p, unsigned int resource,
3451 struct rlimit *new_rlim)
3452 {
3453 struct rlimit *old_rlim = p->signal->rlim + resource;
3454
3455 /* Control the ability to change the hard limit (whether
3456 lowering or raising it), so that the hard limit can
3457 later be used as a safe reset point for the soft limit
3458 upon context transitions. See selinux_bprm_committing_creds. */
3459 if (old_rlim->rlim_max != new_rlim->rlim_max)
3460 return current_has_perm(p, PROCESS__SETRLIMIT);
3461
3462 return 0;
3463 }
3464
3465 static int selinux_task_setscheduler(struct task_struct *p)
3466 {
3467 int rc;
3468
3469 rc = cap_task_setscheduler(p);
3470 if (rc)
3471 return rc;
3472
3473 return current_has_perm(p, PROCESS__SETSCHED);
3474 }
3475
3476 static int selinux_task_getscheduler(struct task_struct *p)
3477 {
3478 return current_has_perm(p, PROCESS__GETSCHED);
3479 }
3480
3481 static int selinux_task_movememory(struct task_struct *p)
3482 {
3483 return current_has_perm(p, PROCESS__SETSCHED);
3484 }
3485
3486 static int selinux_task_kill(struct task_struct *p, struct siginfo *info,
3487 int sig, u32 secid)
3488 {
3489 u32 perm;
3490 int rc;
3491
3492 if (!sig)
3493 perm = PROCESS__SIGNULL; /* null signal; existence test */
3494 else
3495 perm = signal_to_av(sig);
3496 if (secid)
3497 rc = avc_has_perm(secid, task_sid(p),
3498 SECCLASS_PROCESS, perm, NULL);
3499 else
3500 rc = current_has_perm(p, perm);
3501 return rc;
3502 }
3503
3504 static int selinux_task_wait(struct task_struct *p)
3505 {
3506 return task_has_perm(p, current, PROCESS__SIGCHLD);
3507 }
3508
3509 static void selinux_task_to_inode(struct task_struct *p,
3510 struct inode *inode)
3511 {
3512 struct inode_security_struct *isec = inode->i_security;
3513 u32 sid = task_sid(p);
3514
3515 isec->sid = sid;
3516 isec->initialized = 1;
3517 }
3518
3519 /* Returns error only if unable to parse addresses */
3520 static int selinux_parse_skb_ipv4(struct sk_buff *skb,
3521 struct common_audit_data *ad, u8 *proto)
3522 {
3523 int offset, ihlen, ret = -EINVAL;
3524 struct iphdr _iph, *ih;
3525
3526 offset = skb_network_offset(skb);
3527 ih = skb_header_pointer(skb, offset, sizeof(_iph), &_iph);
3528 if (ih == NULL)
3529 goto out;
3530
3531 ihlen = ih->ihl * 4;
3532 if (ihlen < sizeof(_iph))
3533 goto out;
3534
3535 ad->u.net->v4info.saddr = ih->saddr;
3536 ad->u.net->v4info.daddr = ih->daddr;
3537 ret = 0;
3538
3539 if (proto)
3540 *proto = ih->protocol;
3541
3542 switch (ih->protocol) {
3543 case IPPROTO_TCP: {
3544 struct tcphdr _tcph, *th;
3545
3546 if (ntohs(ih->frag_off) & IP_OFFSET)
3547 break;
3548
3549 offset += ihlen;
3550 th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph);
3551 if (th == NULL)
3552 break;
3553
3554 ad->u.net->sport = th->source;
3555 ad->u.net->dport = th->dest;
3556 break;
3557 }
3558
3559 case IPPROTO_UDP: {
3560 struct udphdr _udph, *uh;
3561
3562 if (ntohs(ih->frag_off) & IP_OFFSET)
3563 break;
3564
3565 offset += ihlen;
3566 uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph);
3567 if (uh == NULL)
3568 break;
3569
3570 ad->u.net->sport = uh->source;
3571 ad->u.net->dport = uh->dest;
3572 break;
3573 }
3574
3575 case IPPROTO_DCCP: {
3576 struct dccp_hdr _dccph, *dh;
3577
3578 if (ntohs(ih->frag_off) & IP_OFFSET)
3579 break;
3580
3581 offset += ihlen;
3582 dh = skb_header_pointer(skb, offset, sizeof(_dccph), &_dccph);
3583 if (dh == NULL)
3584 break;
3585
3586 ad->u.net->sport = dh->dccph_sport;
3587 ad->u.net->dport = dh->dccph_dport;
3588 break;
3589 }
3590
3591 default:
3592 break;
3593 }
3594 out:
3595 return ret;
3596 }
3597
3598 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
3599
3600 /* Returns error only if unable to parse addresses */
3601 static int selinux_parse_skb_ipv6(struct sk_buff *skb,
3602 struct common_audit_data *ad, u8 *proto)
3603 {
3604 u8 nexthdr;
3605 int ret = -EINVAL, offset;
3606 struct ipv6hdr _ipv6h, *ip6;
3607 __be16 frag_off;
3608
3609 offset = skb_network_offset(skb);
3610 ip6 = skb_header_pointer(skb, offset, sizeof(_ipv6h), &_ipv6h);
3611 if (ip6 == NULL)
3612 goto out;
3613
3614 ad->u.net->v6info.saddr = ip6->saddr;
3615 ad->u.net->v6info.daddr = ip6->daddr;
3616 ret = 0;
3617
3618 nexthdr = ip6->nexthdr;
3619 offset += sizeof(_ipv6h);
3620 offset = ipv6_skip_exthdr(skb, offset, &nexthdr, &frag_off);
3621 if (offset < 0)
3622 goto out;
3623
3624 if (proto)
3625 *proto = nexthdr;
3626
3627 switch (nexthdr) {
3628 case IPPROTO_TCP: {
3629 struct tcphdr _tcph, *th;
3630
3631 th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph);
3632 if (th == NULL)
3633 break;
3634
3635 ad->u.net->sport = th->source;
3636 ad->u.net->dport = th->dest;
3637 break;
3638 }
3639
3640 case IPPROTO_UDP: {
3641 struct udphdr _udph, *uh;
3642
3643 uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph);
3644 if (uh == NULL)
3645 break;
3646
3647 ad->u.net->sport = uh->source;
3648 ad->u.net->dport = uh->dest;
3649 break;
3650 }
3651
3652 case IPPROTO_DCCP: {
3653 struct dccp_hdr _dccph, *dh;
3654
3655 dh = skb_header_pointer(skb, offset, sizeof(_dccph), &_dccph);
3656 if (dh == NULL)
3657 break;
3658
3659 ad->u.net->sport = dh->dccph_sport;
3660 ad->u.net->dport = dh->dccph_dport;
3661 break;
3662 }
3663
3664 /* includes fragments */
3665 default:
3666 break;
3667 }
3668 out:
3669 return ret;
3670 }
3671
3672 #endif /* IPV6 */
3673
3674 static int selinux_parse_skb(struct sk_buff *skb, struct common_audit_data *ad,
3675 char **_addrp, int src, u8 *proto)
3676 {
3677 char *addrp;
3678 int ret;
3679
3680 switch (ad->u.net->family) {
3681 case PF_INET:
3682 ret = selinux_parse_skb_ipv4(skb, ad, proto);
3683 if (ret)
3684 goto parse_error;
3685 addrp = (char *)(src ? &ad->u.net->v4info.saddr :
3686 &ad->u.net->v4info.daddr);
3687 goto okay;
3688
3689 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
3690 case PF_INET6:
3691 ret = selinux_parse_skb_ipv6(skb, ad, proto);
3692 if (ret)
3693 goto parse_error;
3694 addrp = (char *)(src ? &ad->u.net->v6info.saddr :
3695 &ad->u.net->v6info.daddr);
3696 goto okay;
3697 #endif /* IPV6 */
3698 default:
3699 addrp = NULL;
3700 goto okay;
3701 }
3702
3703 parse_error:
3704 printk(KERN_WARNING
3705 "SELinux: failure in selinux_parse_skb(),"
3706 " unable to parse packet\n");
3707 return ret;
3708
3709 okay:
3710 if (_addrp)
3711 *_addrp = addrp;
3712 return 0;
3713 }
3714
3715 /**
3716 * selinux_skb_peerlbl_sid - Determine the peer label of a packet
3717 * @skb: the packet
3718 * @family: protocol family
3719 * @sid: the packet's peer label SID
3720 *
3721 * Description:
3722 * Check the various different forms of network peer labeling and determine
3723 * the peer label/SID for the packet; most of the magic actually occurs in
3724 * the security server function security_net_peersid_cmp(). The function
3725 * returns zero if the value in @sid is valid (although it may be SECSID_NULL)
3726 * or -EACCES if @sid is invalid due to inconsistencies with the different
3727 * peer labels.
3728 *
3729 */
3730 static int selinux_skb_peerlbl_sid(struct sk_buff *skb, u16 family, u32 *sid)
3731 {
3732 int err;
3733 u32 xfrm_sid;
3734 u32 nlbl_sid;
3735 u32 nlbl_type;
3736
3737 selinux_skb_xfrm_sid(skb, &xfrm_sid);
3738 selinux_netlbl_skbuff_getsid(skb, family, &nlbl_type, &nlbl_sid);
3739
3740 err = security_net_peersid_resolve(nlbl_sid, nlbl_type, xfrm_sid, sid);
3741 if (unlikely(err)) {
3742 printk(KERN_WARNING
3743 "SELinux: failure in selinux_skb_peerlbl_sid(),"
3744 " unable to determine packet's peer label\n");
3745 return -EACCES;
3746 }
3747
3748 return 0;
3749 }
3750
3751 /* socket security operations */
3752
3753 static int socket_sockcreate_sid(const struct task_security_struct *tsec,
3754 u16 secclass, u32 *socksid)
3755 {
3756 if (tsec->sockcreate_sid > SECSID_NULL) {
3757 *socksid = tsec->sockcreate_sid;
3758 return 0;
3759 }
3760
3761 return security_transition_sid(tsec->sid, tsec->sid, secclass, NULL,
3762 socksid);
3763 }
3764
3765 static int sock_has_perm(struct task_struct *task, struct sock *sk, u32 perms)
3766 {
3767 struct sk_security_struct *sksec = sk->sk_security;
3768 struct common_audit_data ad;
3769 struct lsm_network_audit net = {0,};
3770 u32 tsid = task_sid(task);
3771
3772 if (sksec->sid == SECINITSID_KERNEL)
3773 return 0;
3774
3775 ad.type = LSM_AUDIT_DATA_NET;
3776 ad.u.net = &net;
3777 ad.u.net->sk = sk;
3778
3779 return avc_has_perm(tsid, sksec->sid, sksec->sclass, perms, &ad);
3780 }
3781
3782 static int selinux_socket_create(int family, int type,
3783 int protocol, int kern)
3784 {
3785 const struct task_security_struct *tsec = current_security();
3786 u32 newsid;
3787 u16 secclass;
3788 int rc;
3789
3790 if (kern)
3791 return 0;
3792
3793 secclass = socket_type_to_security_class(family, type, protocol);
3794 rc = socket_sockcreate_sid(tsec, secclass, &newsid);
3795 if (rc)
3796 return rc;
3797
3798 return avc_has_perm(tsec->sid, newsid, secclass, SOCKET__CREATE, NULL);
3799 }
3800
3801 static int selinux_socket_post_create(struct socket *sock, int family,
3802 int type, int protocol, int kern)
3803 {
3804 const struct task_security_struct *tsec = current_security();
3805 struct inode_security_struct *isec = SOCK_INODE(sock)->i_security;
3806 struct sk_security_struct *sksec;
3807 int err = 0;
3808
3809 isec->sclass = socket_type_to_security_class(family, type, protocol);
3810
3811 if (kern)
3812 isec->sid = SECINITSID_KERNEL;
3813 else {
3814 err = socket_sockcreate_sid(tsec, isec->sclass, &(isec->sid));
3815 if (err)
3816 return err;
3817 }
3818
3819 isec->initialized = 1;
3820
3821 if (sock->sk) {
3822 sksec = sock->sk->sk_security;
3823 sksec->sid = isec->sid;
3824 sksec->sclass = isec->sclass;
3825 err = selinux_netlbl_socket_post_create(sock->sk, family);
3826 }
3827
3828 return err;
3829 }
3830
3831 /* Range of port numbers used to automatically bind.
3832 Need to determine whether we should perform a name_bind
3833 permission check between the socket and the port number. */
3834
3835 static int selinux_socket_bind(struct socket *sock, struct sockaddr *address, int addrlen)
3836 {
3837 struct sock *sk = sock->sk;
3838 u16 family;
3839 int err;
3840
3841 err = sock_has_perm(current, sk, SOCKET__BIND);
3842 if (err)
3843 goto out;
3844
3845 /*
3846 * If PF_INET or PF_INET6, check name_bind permission for the port.
3847 * Multiple address binding for SCTP is not supported yet: we just
3848 * check the first address now.
3849 */
3850 family = sk->sk_family;
3851 if (family == PF_INET || family == PF_INET6) {
3852 char *addrp;
3853 struct sk_security_struct *sksec = sk->sk_security;
3854 struct common_audit_data ad;
3855 struct lsm_network_audit net = {0,};
3856 struct sockaddr_in *addr4 = NULL;
3857 struct sockaddr_in6 *addr6 = NULL;
3858 unsigned short snum;
3859 u32 sid, node_perm;
3860
3861 if (family == PF_INET) {
3862 addr4 = (struct sockaddr_in *)address;
3863 snum = ntohs(addr4->sin_port);
3864 addrp = (char *)&addr4->sin_addr.s_addr;
3865 } else {
3866 addr6 = (struct sockaddr_in6 *)address;
3867 snum = ntohs(addr6->sin6_port);
3868 addrp = (char *)&addr6->sin6_addr.s6_addr;
3869 }
3870
3871 if (snum) {
3872 int low, high;
3873
3874 inet_get_local_port_range(&low, &high);
3875
3876 if (snum < max(PROT_SOCK, low) || snum > high) {
3877 err = sel_netport_sid(sk->sk_protocol,
3878 snum, &sid);
3879 if (err)
3880 goto out;
3881 ad.type = LSM_AUDIT_DATA_NET;
3882 ad.u.net = &net;
3883 ad.u.net->sport = htons(snum);
3884 ad.u.net->family = family;
3885 err = avc_has_perm(sksec->sid, sid,
3886 sksec->sclass,
3887 SOCKET__NAME_BIND, &ad);
3888 if (err)
3889 goto out;
3890 }
3891 }
3892
3893 switch (sksec->sclass) {
3894 case SECCLASS_TCP_SOCKET:
3895 node_perm = TCP_SOCKET__NODE_BIND;
3896 break;
3897
3898 case SECCLASS_UDP_SOCKET:
3899 node_perm = UDP_SOCKET__NODE_BIND;
3900 break;
3901
3902 case SECCLASS_DCCP_SOCKET:
3903 node_perm = DCCP_SOCKET__NODE_BIND;
3904 break;
3905
3906 default:
3907 node_perm = RAWIP_SOCKET__NODE_BIND;
3908 break;
3909 }
3910
3911 err = sel_netnode_sid(addrp, family, &sid);
3912 if (err)
3913 goto out;
3914
3915 ad.type = LSM_AUDIT_DATA_NET;
3916 ad.u.net = &net;
3917 ad.u.net->sport = htons(snum);
3918 ad.u.net->family = family;
3919
3920 if (family == PF_INET)
3921 ad.u.net->v4info.saddr = addr4->sin_addr.s_addr;
3922 else
3923 ad.u.net->v6info.saddr = addr6->sin6_addr;
3924
3925 err = avc_has_perm(sksec->sid, sid,
3926 sksec->sclass, node_perm, &ad);
3927 if (err)
3928 goto out;
3929 }
3930 out:
3931 return err;
3932 }
3933
3934 static int selinux_socket_connect(struct socket *sock, struct sockaddr *address, int addrlen)
3935 {
3936 struct sock *sk = sock->sk;
3937 struct sk_security_struct *sksec = sk->sk_security;
3938 int err;
3939
3940 err = sock_has_perm(current, sk, SOCKET__CONNECT);
3941 if (err)
3942 return err;
3943
3944 /*
3945 * If a TCP or DCCP socket, check name_connect permission for the port.
3946 */
3947 if (sksec->sclass == SECCLASS_TCP_SOCKET ||
3948 sksec->sclass == SECCLASS_DCCP_SOCKET) {
3949 struct common_audit_data ad;
3950 struct lsm_network_audit net = {0,};
3951 struct sockaddr_in *addr4 = NULL;
3952 struct sockaddr_in6 *addr6 = NULL;
3953 unsigned short snum;
3954 u32 sid, perm;
3955
3956 if (sk->sk_family == PF_INET) {
3957 addr4 = (struct sockaddr_in *)address;
3958 if (addrlen < sizeof(struct sockaddr_in))
3959 return -EINVAL;
3960 snum = ntohs(addr4->sin_port);
3961 } else {
3962 addr6 = (struct sockaddr_in6 *)address;
3963 if (addrlen < SIN6_LEN_RFC2133)
3964 return -EINVAL;
3965 snum = ntohs(addr6->sin6_port);
3966 }
3967
3968 err = sel_netport_sid(sk->sk_protocol, snum, &sid);
3969 if (err)
3970 goto out;
3971
3972 perm = (sksec->sclass == SECCLASS_TCP_SOCKET) ?
3973 TCP_SOCKET__NAME_CONNECT : DCCP_SOCKET__NAME_CONNECT;
3974
3975 ad.type = LSM_AUDIT_DATA_NET;
3976 ad.u.net = &net;
3977 ad.u.net->dport = htons(snum);
3978 ad.u.net->family = sk->sk_family;
3979 err = avc_has_perm(sksec->sid, sid, sksec->sclass, perm, &ad);
3980 if (err)
3981 goto out;
3982 }
3983
3984 err = selinux_netlbl_socket_connect(sk, address);
3985
3986 out:
3987 return err;
3988 }
3989
3990 static int selinux_socket_listen(struct socket *sock, int backlog)
3991 {
3992 return sock_has_perm(current, sock->sk, SOCKET__LISTEN);
3993 }
3994
3995 static int selinux_socket_accept(struct socket *sock, struct socket *newsock)
3996 {
3997 int err;
3998 struct inode_security_struct *isec;
3999 struct inode_security_struct *newisec;
4000
4001 err = sock_has_perm(current, sock->sk, SOCKET__ACCEPT);
4002 if (err)
4003 return err;
4004
4005 newisec = SOCK_INODE(newsock)->i_security;
4006
4007 isec = SOCK_INODE(sock)->i_security;
4008 newisec->sclass = isec->sclass;
4009 newisec->sid = isec->sid;
4010 newisec->initialized = 1;
4011
4012 return 0;
4013 }
4014
4015 static int selinux_socket_sendmsg(struct socket *sock, struct msghdr *msg,
4016 int size)
4017 {
4018 return sock_has_perm(current, sock->sk, SOCKET__WRITE);
4019 }
4020
4021 static int selinux_socket_recvmsg(struct socket *sock, struct msghdr *msg,
4022 int size, int flags)
4023 {
4024 return sock_has_perm(current, sock->sk, SOCKET__READ);
4025 }
4026
4027 static int selinux_socket_getsockname(struct socket *sock)
4028 {
4029 return sock_has_perm(current, sock->sk, SOCKET__GETATTR);
4030 }
4031
4032 static int selinux_socket_getpeername(struct socket *sock)
4033 {
4034 return sock_has_perm(current, sock->sk, SOCKET__GETATTR);
4035 }
4036
4037 static int selinux_socket_setsockopt(struct socket *sock, int level, int optname)
4038 {
4039 int err;
4040
4041 err = sock_has_perm(current, sock->sk, SOCKET__SETOPT);
4042 if (err)
4043 return err;
4044
4045 return selinux_netlbl_socket_setsockopt(sock, level, optname);
4046 }
4047
4048 static int selinux_socket_getsockopt(struct socket *sock, int level,
4049 int optname)
4050 {
4051 return sock_has_perm(current, sock->sk, SOCKET__GETOPT);
4052 }
4053
4054 static int selinux_socket_shutdown(struct socket *sock, int how)
4055 {
4056 return sock_has_perm(current, sock->sk, SOCKET__SHUTDOWN);
4057 }
4058
4059 static int selinux_socket_unix_stream_connect(struct sock *sock,
4060 struct sock *other,
4061 struct sock *newsk)
4062 {
4063 struct sk_security_struct *sksec_sock = sock->sk_security;
4064 struct sk_security_struct *sksec_other = other->sk_security;
4065 struct sk_security_struct *sksec_new = newsk->sk_security;
4066 struct common_audit_data ad;
4067 struct lsm_network_audit net = {0,};
4068 int err;
4069
4070 ad.type = LSM_AUDIT_DATA_NET;
4071 ad.u.net = &net;
4072 ad.u.net->sk = other;
4073
4074 err = avc_has_perm(sksec_sock->sid, sksec_other->sid,
4075 sksec_other->sclass,
4076 UNIX_STREAM_SOCKET__CONNECTTO, &ad);
4077 if (err)
4078 return err;
4079
4080 /* server child socket */
4081 sksec_new->peer_sid = sksec_sock->sid;
4082 err = security_sid_mls_copy(sksec_other->sid, sksec_sock->sid,
4083 &sksec_new->sid);
4084 if (err)
4085 return err;
4086
4087 /* connecting socket */
4088 sksec_sock->peer_sid = sksec_new->sid;
4089
4090 return 0;
4091 }
4092
4093 static int selinux_socket_unix_may_send(struct socket *sock,
4094 struct socket *other)
4095 {
4096 struct sk_security_struct *ssec = sock->sk->sk_security;
4097 struct sk_security_struct *osec = other->sk->sk_security;
4098 struct common_audit_data ad;
4099 struct lsm_network_audit net = {0,};
4100
4101 ad.type = LSM_AUDIT_DATA_NET;
4102 ad.u.net = &net;
4103 ad.u.net->sk = other->sk;
4104
4105 return avc_has_perm(ssec->sid, osec->sid, osec->sclass, SOCKET__SENDTO,
4106 &ad);
4107 }
4108
4109 static int selinux_inet_sys_rcv_skb(int ifindex, char *addrp, u16 family,
4110 u32 peer_sid,
4111 struct common_audit_data *ad)
4112 {
4113 int err;
4114 u32 if_sid;
4115 u32 node_sid;
4116
4117 err = sel_netif_sid(ifindex, &if_sid);
4118 if (err)
4119 return err;
4120 err = avc_has_perm(peer_sid, if_sid,
4121 SECCLASS_NETIF, NETIF__INGRESS, ad);
4122 if (err)
4123 return err;
4124
4125 err = sel_netnode_sid(addrp, family, &node_sid);
4126 if (err)
4127 return err;
4128 return avc_has_perm(peer_sid, node_sid,
4129 SECCLASS_NODE, NODE__RECVFROM, ad);
4130 }
4131
4132 static int selinux_sock_rcv_skb_compat(struct sock *sk, struct sk_buff *skb,
4133 u16 family)
4134 {
4135 int err = 0;
4136 struct sk_security_struct *sksec = sk->sk_security;
4137 u32 sk_sid = sksec->sid;
4138 struct common_audit_data ad;
4139 struct lsm_network_audit net = {0,};
4140 char *addrp;
4141
4142 ad.type = LSM_AUDIT_DATA_NET;
4143 ad.u.net = &net;
4144 ad.u.net->netif = skb->skb_iif;
4145 ad.u.net->family = family;
4146 err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL);
4147 if (err)
4148 return err;
4149
4150 if (selinux_secmark_enabled()) {
4151 err = avc_has_perm(sk_sid, skb->secmark, SECCLASS_PACKET,
4152 PACKET__RECV, &ad);
4153 if (err)
4154 return err;
4155 }
4156
4157 err = selinux_netlbl_sock_rcv_skb(sksec, skb, family, &ad);
4158 if (err)
4159 return err;
4160 err = selinux_xfrm_sock_rcv_skb(sksec->sid, skb, &ad);
4161
4162 return err;
4163 }
4164
4165 static int selinux_socket_sock_rcv_skb(struct sock *sk, struct sk_buff *skb)
4166 {
4167 int err;
4168 struct sk_security_struct *sksec = sk->sk_security;
4169 u16 family = sk->sk_family;
4170 u32 sk_sid = sksec->sid;
4171 struct common_audit_data ad;
4172 struct lsm_network_audit net = {0,};
4173 char *addrp;
4174 u8 secmark_active;
4175 u8 peerlbl_active;
4176
4177 if (family != PF_INET && family != PF_INET6)
4178 return 0;
4179
4180 /* Handle mapped IPv4 packets arriving via IPv6 sockets */
4181 if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
4182 family = PF_INET;
4183
4184 /* If any sort of compatibility mode is enabled then handoff processing
4185 * to the selinux_sock_rcv_skb_compat() function to deal with the
4186 * special handling. We do this in an attempt to keep this function
4187 * as fast and as clean as possible. */
4188 if (!selinux_policycap_netpeer)
4189 return selinux_sock_rcv_skb_compat(sk, skb, family);
4190
4191 secmark_active = selinux_secmark_enabled();
4192 peerlbl_active = netlbl_enabled() || selinux_xfrm_enabled();
4193 if (!secmark_active && !peerlbl_active)
4194 return 0;
4195
4196 ad.type = LSM_AUDIT_DATA_NET;
4197 ad.u.net = &net;
4198 ad.u.net->netif = skb->skb_iif;
4199 ad.u.net->family = family;
4200 err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL);
4201 if (err)
4202 return err;
4203
4204 if (peerlbl_active) {
4205 u32 peer_sid;
4206
4207 err = selinux_skb_peerlbl_sid(skb, family, &peer_sid);
4208 if (err)
4209 return err;
4210 err = selinux_inet_sys_rcv_skb(skb->skb_iif, addrp, family,
4211 peer_sid, &ad);
4212 if (err) {
4213 selinux_netlbl_err(skb, err, 0);
4214 return err;
4215 }
4216 err = avc_has_perm(sk_sid, peer_sid, SECCLASS_PEER,
4217 PEER__RECV, &ad);
4218 if (err)
4219 selinux_netlbl_err(skb, err, 0);
4220 }
4221
4222 if (secmark_active) {
4223 err = avc_has_perm(sk_sid, skb->secmark, SECCLASS_PACKET,
4224 PACKET__RECV, &ad);
4225 if (err)
4226 return err;
4227 }
4228
4229 return err;
4230 }
4231
4232 static int selinux_socket_getpeersec_stream(struct socket *sock, char __user *optval,
4233 int __user *optlen, unsigned len)
4234 {
4235 int err = 0;
4236 char *scontext;
4237 u32 scontext_len;
4238 struct sk_security_struct *sksec = sock->sk->sk_security;
4239 u32 peer_sid = SECSID_NULL;
4240
4241 if (sksec->sclass == SECCLASS_UNIX_STREAM_SOCKET ||
4242 sksec->sclass == SECCLASS_TCP_SOCKET)
4243 peer_sid = sksec->peer_sid;
4244 if (peer_sid == SECSID_NULL)
4245 return -ENOPROTOOPT;
4246
4247 err = security_sid_to_context(peer_sid, &scontext, &scontext_len);
4248 if (err)
4249 return err;
4250
4251 if (scontext_len > len) {
4252 err = -ERANGE;
4253 goto out_len;
4254 }
4255
4256 if (copy_to_user(optval, scontext, scontext_len))
4257 err = -EFAULT;
4258
4259 out_len:
4260 if (put_user(scontext_len, optlen))
4261 err = -EFAULT;
4262 kfree(scontext);
4263 return err;
4264 }
4265
4266 static int selinux_socket_getpeersec_dgram(struct socket *sock, struct sk_buff *skb, u32 *secid)
4267 {
4268 u32 peer_secid = SECSID_NULL;
4269 u16 family;
4270
4271 if (skb && skb->protocol == htons(ETH_P_IP))
4272 family = PF_INET;
4273 else if (skb && skb->protocol == htons(ETH_P_IPV6))
4274 family = PF_INET6;
4275 else if (sock)
4276 family = sock->sk->sk_family;
4277 else
4278 goto out;
4279
4280 if (sock && family == PF_UNIX)
4281 selinux_inode_getsecid(SOCK_INODE(sock), &peer_secid);
4282 else if (skb)
4283 selinux_skb_peerlbl_sid(skb, family, &peer_secid);
4284
4285 out:
4286 *secid = peer_secid;
4287 if (peer_secid == SECSID_NULL)
4288 return -EINVAL;
4289 return 0;
4290 }
4291
4292 static int selinux_sk_alloc_security(struct sock *sk, int family, gfp_t priority)
4293 {
4294 struct sk_security_struct *sksec;
4295
4296 sksec = kzalloc(sizeof(*sksec), priority);
4297 if (!sksec)
4298 return -ENOMEM;
4299
4300 sksec->peer_sid = SECINITSID_UNLABELED;
4301 sksec->sid = SECINITSID_UNLABELED;
4302 selinux_netlbl_sk_security_reset(sksec);
4303 sk->sk_security = sksec;
4304
4305 return 0;
4306 }
4307
4308 static void selinux_sk_free_security(struct sock *sk)
4309 {
4310 struct sk_security_struct *sksec = sk->sk_security;
4311
4312 sk->sk_security = NULL;
4313 selinux_netlbl_sk_security_free(sksec);
4314 kfree(sksec);
4315 }
4316
4317 static void selinux_sk_clone_security(const struct sock *sk, struct sock *newsk)
4318 {
4319 struct sk_security_struct *sksec = sk->sk_security;
4320 struct sk_security_struct *newsksec = newsk->sk_security;
4321
4322 newsksec->sid = sksec->sid;
4323 newsksec->peer_sid = sksec->peer_sid;
4324 newsksec->sclass = sksec->sclass;
4325
4326 selinux_netlbl_sk_security_reset(newsksec);
4327 }
4328
4329 static void selinux_sk_getsecid(struct sock *sk, u32 *secid)
4330 {
4331 if (!sk)
4332 *secid = SECINITSID_ANY_SOCKET;
4333 else {
4334 struct sk_security_struct *sksec = sk->sk_security;
4335
4336 *secid = sksec->sid;
4337 }
4338 }
4339
4340 static void selinux_sock_graft(struct sock *sk, struct socket *parent)
4341 {
4342 struct inode_security_struct *isec = SOCK_INODE(parent)->i_security;
4343 struct sk_security_struct *sksec = sk->sk_security;
4344
4345 if (sk->sk_family == PF_INET || sk->sk_family == PF_INET6 ||
4346 sk->sk_family == PF_UNIX)
4347 isec->sid = sksec->sid;
4348 sksec->sclass = isec->sclass;
4349 }
4350
4351 static int selinux_inet_conn_request(struct sock *sk, struct sk_buff *skb,
4352 struct request_sock *req)
4353 {
4354 struct sk_security_struct *sksec = sk->sk_security;
4355 int err;
4356 u16 family = sk->sk_family;
4357 u32 newsid;
4358 u32 peersid;
4359
4360 /* handle mapped IPv4 packets arriving via IPv6 sockets */
4361 if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
4362 family = PF_INET;
4363
4364 err = selinux_skb_peerlbl_sid(skb, family, &peersid);
4365 if (err)
4366 return err;
4367 if (peersid == SECSID_NULL) {
4368 req->secid = sksec->sid;
4369 req->peer_secid = SECSID_NULL;
4370 } else {
4371 err = security_sid_mls_copy(sksec->sid, peersid, &newsid);
4372 if (err)
4373 return err;
4374 req->secid = newsid;
4375 req->peer_secid = peersid;
4376 }
4377
4378 return selinux_netlbl_inet_conn_request(req, family);
4379 }
4380
4381 static void selinux_inet_csk_clone(struct sock *newsk,
4382 const struct request_sock *req)
4383 {
4384 struct sk_security_struct *newsksec = newsk->sk_security;
4385
4386 newsksec->sid = req->secid;
4387 newsksec->peer_sid = req->peer_secid;
4388 /* NOTE: Ideally, we should also get the isec->sid for the
4389 new socket in sync, but we don't have the isec available yet.
4390 So we will wait until sock_graft to do it, by which
4391 time it will have been created and available. */
4392
4393 /* We don't need to take any sort of lock here as we are the only
4394 * thread with access to newsksec */
4395 selinux_netlbl_inet_csk_clone(newsk, req->rsk_ops->family);
4396 }
4397
4398 static void selinux_inet_conn_established(struct sock *sk, struct sk_buff *skb)
4399 {
4400 u16 family = sk->sk_family;
4401 struct sk_security_struct *sksec = sk->sk_security;
4402
4403 /* handle mapped IPv4 packets arriving via IPv6 sockets */
4404 if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
4405 family = PF_INET;
4406
4407 selinux_skb_peerlbl_sid(skb, family, &sksec->peer_sid);
4408 }
4409
4410 static int selinux_secmark_relabel_packet(u32 sid)
4411 {
4412 const struct task_security_struct *__tsec;
4413 u32 tsid;
4414
4415 __tsec = current_security();
4416 tsid = __tsec->sid;
4417
4418 return avc_has_perm(tsid, sid, SECCLASS_PACKET, PACKET__RELABELTO, NULL);
4419 }
4420
4421 static void selinux_secmark_refcount_inc(void)
4422 {
4423 atomic_inc(&selinux_secmark_refcount);
4424 }
4425
4426 static void selinux_secmark_refcount_dec(void)
4427 {
4428 atomic_dec(&selinux_secmark_refcount);
4429 }
4430
4431 static void selinux_req_classify_flow(const struct request_sock *req,
4432 struct flowi *fl)
4433 {
4434 fl->flowi_secid = req->secid;
4435 }
4436
4437 static int selinux_tun_dev_create(void)
4438 {
4439 u32 sid = current_sid();
4440
4441 /* we aren't taking into account the "sockcreate" SID since the socket
4442 * that is being created here is not a socket in the traditional sense,
4443 * instead it is a private sock, accessible only to the kernel, and
4444 * representing a wide range of network traffic spanning multiple
4445 * connections unlike traditional sockets - check the TUN driver to
4446 * get a better understanding of why this socket is special */
4447
4448 return avc_has_perm(sid, sid, SECCLASS_TUN_SOCKET, TUN_SOCKET__CREATE,
4449 NULL);
4450 }
4451
4452 static void selinux_tun_dev_post_create(struct sock *sk)
4453 {
4454 struct sk_security_struct *sksec = sk->sk_security;
4455
4456 /* we don't currently perform any NetLabel based labeling here and it
4457 * isn't clear that we would want to do so anyway; while we could apply
4458 * labeling without the support of the TUN user the resulting labeled
4459 * traffic from the other end of the connection would almost certainly
4460 * cause confusion to the TUN user that had no idea network labeling
4461 * protocols were being used */
4462
4463 /* see the comments in selinux_tun_dev_create() about why we don't use
4464 * the sockcreate SID here */
4465
4466 sksec->sid = current_sid();
4467 sksec->sclass = SECCLASS_TUN_SOCKET;
4468 }
4469
4470 static int selinux_tun_dev_attach(struct sock *sk)
4471 {
4472 struct sk_security_struct *sksec = sk->sk_security;
4473 u32 sid = current_sid();
4474 int err;
4475
4476 err = avc_has_perm(sid, sksec->sid, SECCLASS_TUN_SOCKET,
4477 TUN_SOCKET__RELABELFROM, NULL);
4478 if (err)
4479 return err;
4480 err = avc_has_perm(sid, sid, SECCLASS_TUN_SOCKET,
4481 TUN_SOCKET__RELABELTO, NULL);
4482 if (err)
4483 return err;
4484
4485 sksec->sid = sid;
4486
4487 return 0;
4488 }
4489
4490 static int selinux_nlmsg_perm(struct sock *sk, struct sk_buff *skb)
4491 {
4492 int err = 0;
4493 u32 perm;
4494 struct nlmsghdr *nlh;
4495 struct sk_security_struct *sksec = sk->sk_security;
4496
4497 if (skb->len < NLMSG_SPACE(0)) {
4498 err = -EINVAL;
4499 goto out;
4500 }
4501 nlh = nlmsg_hdr(skb);
4502
4503 err = selinux_nlmsg_lookup(sksec->sclass, nlh->nlmsg_type, &perm);
4504 if (err) {
4505 if (err == -EINVAL) {
4506 audit_log(current->audit_context, GFP_KERNEL, AUDIT_SELINUX_ERR,
4507 "SELinux: unrecognized netlink message"
4508 " type=%hu for sclass=%hu\n",
4509 nlh->nlmsg_type, sksec->sclass);
4510 if (!selinux_enforcing || security_get_allow_unknown())
4511 err = 0;
4512 }
4513
4514 /* Ignore */
4515 if (err == -ENOENT)
4516 err = 0;
4517 goto out;
4518 }
4519
4520 err = sock_has_perm(current, sk, perm);
4521 out:
4522 return err;
4523 }
4524
4525 #ifdef CONFIG_NETFILTER
4526
4527 static unsigned int selinux_ip_forward(struct sk_buff *skb, int ifindex,
4528 u16 family)
4529 {
4530 int err;
4531 char *addrp;
4532 u32 peer_sid;
4533 struct common_audit_data ad;
4534 struct lsm_network_audit net = {0,};
4535 u8 secmark_active;
4536 u8 netlbl_active;
4537 u8 peerlbl_active;
4538
4539 if (!selinux_policycap_netpeer)
4540 return NF_ACCEPT;
4541
4542 secmark_active = selinux_secmark_enabled();
4543 netlbl_active = netlbl_enabled();
4544 peerlbl_active = netlbl_active || selinux_xfrm_enabled();
4545 if (!secmark_active && !peerlbl_active)
4546 return NF_ACCEPT;
4547
4548 if (selinux_skb_peerlbl_sid(skb, family, &peer_sid) != 0)
4549 return NF_DROP;
4550
4551 ad.type = LSM_AUDIT_DATA_NET;
4552 ad.u.net = &net;
4553 ad.u.net->netif = ifindex;
4554 ad.u.net->family = family;
4555 if (selinux_parse_skb(skb, &ad, &addrp, 1, NULL) != 0)
4556 return NF_DROP;
4557
4558 if (peerlbl_active) {
4559 err = selinux_inet_sys_rcv_skb(ifindex, addrp, family,
4560 peer_sid, &ad);
4561 if (err) {
4562 selinux_netlbl_err(skb, err, 1);
4563 return NF_DROP;
4564 }
4565 }
4566
4567 if (secmark_active)
4568 if (avc_has_perm(peer_sid, skb->secmark,
4569 SECCLASS_PACKET, PACKET__FORWARD_IN, &ad))
4570 return NF_DROP;
4571
4572 if (netlbl_active)
4573 /* we do this in the FORWARD path and not the POST_ROUTING
4574 * path because we want to make sure we apply the necessary
4575 * labeling before IPsec is applied so we can leverage AH
4576 * protection */
4577 if (selinux_netlbl_skbuff_setsid(skb, family, peer_sid) != 0)
4578 return NF_DROP;
4579
4580 return NF_ACCEPT;
4581 }
4582
4583 static unsigned int selinux_ipv4_forward(unsigned int hooknum,
4584 struct sk_buff *skb,
4585 const struct net_device *in,
4586 const struct net_device *out,
4587 int (*okfn)(struct sk_buff *))
4588 {
4589 return selinux_ip_forward(skb, in->ifindex, PF_INET);
4590 }
4591
4592 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
4593 static unsigned int selinux_ipv6_forward(unsigned int hooknum,
4594 struct sk_buff *skb,
4595 const struct net_device *in,
4596 const struct net_device *out,
4597 int (*okfn)(struct sk_buff *))
4598 {
4599 return selinux_ip_forward(skb, in->ifindex, PF_INET6);
4600 }
4601 #endif /* IPV6 */
4602
4603 static unsigned int selinux_ip_output(struct sk_buff *skb,
4604 u16 family)
4605 {
4606 u32 sid;
4607
4608 if (!netlbl_enabled())
4609 return NF_ACCEPT;
4610
4611 /* we do this in the LOCAL_OUT path and not the POST_ROUTING path
4612 * because we want to make sure we apply the necessary labeling
4613 * before IPsec is applied so we can leverage AH protection */
4614 if (skb->sk) {
4615 struct sk_security_struct *sksec = skb->sk->sk_security;
4616 sid = sksec->sid;
4617 } else
4618 sid = SECINITSID_KERNEL;
4619 if (selinux_netlbl_skbuff_setsid(skb, family, sid) != 0)
4620 return NF_DROP;
4621
4622 return NF_ACCEPT;
4623 }
4624
4625 static unsigned int selinux_ipv4_output(unsigned int hooknum,
4626 struct sk_buff *skb,
4627 const struct net_device *in,
4628 const struct net_device *out,
4629 int (*okfn)(struct sk_buff *))
4630 {
4631 return selinux_ip_output(skb, PF_INET);
4632 }
4633
4634 static unsigned int selinux_ip_postroute_compat(struct sk_buff *skb,
4635 int ifindex,
4636 u16 family)
4637 {
4638 struct sock *sk = skb->sk;
4639 struct sk_security_struct *sksec;
4640 struct common_audit_data ad;
4641 struct lsm_network_audit net = {0,};
4642 char *addrp;
4643 u8 proto;
4644
4645 if (sk == NULL)
4646 return NF_ACCEPT;
4647 sksec = sk->sk_security;
4648
4649 ad.type = LSM_AUDIT_DATA_NET;
4650 ad.u.net = &net;
4651 ad.u.net->netif = ifindex;
4652 ad.u.net->family = family;
4653 if (selinux_parse_skb(skb, &ad, &addrp, 0, &proto))
4654 return NF_DROP;
4655
4656 if (selinux_secmark_enabled())
4657 if (avc_has_perm(sksec->sid, skb->secmark,
4658 SECCLASS_PACKET, PACKET__SEND, &ad))
4659 return NF_DROP_ERR(-ECONNREFUSED);
4660
4661 if (selinux_xfrm_postroute_last(sksec->sid, skb, &ad, proto))
4662 return NF_DROP_ERR(-ECONNREFUSED);
4663
4664 return NF_ACCEPT;
4665 }
4666
4667 static unsigned int selinux_ip_postroute(struct sk_buff *skb, int ifindex,
4668 u16 family)
4669 {
4670 u32 secmark_perm;
4671 u32 peer_sid;
4672 struct sock *sk;
4673 struct common_audit_data ad;
4674 struct lsm_network_audit net = {0,};
4675 char *addrp;
4676 u8 secmark_active;
4677 u8 peerlbl_active;
4678
4679 /* If any sort of compatibility mode is enabled then handoff processing
4680 * to the selinux_ip_postroute_compat() function to deal with the
4681 * special handling. We do this in an attempt to keep this function
4682 * as fast and as clean as possible. */
4683 if (!selinux_policycap_netpeer)
4684 return selinux_ip_postroute_compat(skb, ifindex, family);
4685 #ifdef CONFIG_XFRM
4686 /* If skb->dst->xfrm is non-NULL then the packet is undergoing an IPsec
4687 * packet transformation so allow the packet to pass without any checks
4688 * since we'll have another chance to perform access control checks
4689 * when the packet is on it's final way out.
4690 * NOTE: there appear to be some IPv6 multicast cases where skb->dst
4691 * is NULL, in this case go ahead and apply access control. */
4692 if (skb_dst(skb) != NULL && skb_dst(skb)->xfrm != NULL)
4693 return NF_ACCEPT;
4694 #endif
4695 secmark_active = selinux_secmark_enabled();
4696 peerlbl_active = netlbl_enabled() || selinux_xfrm_enabled();
4697 if (!secmark_active && !peerlbl_active)
4698 return NF_ACCEPT;
4699
4700 /* if the packet is being forwarded then get the peer label from the
4701 * packet itself; otherwise check to see if it is from a local
4702 * application or the kernel, if from an application get the peer label
4703 * from the sending socket, otherwise use the kernel's sid */
4704 sk = skb->sk;
4705 if (sk == NULL) {
4706 if (skb->skb_iif) {
4707 secmark_perm = PACKET__FORWARD_OUT;
4708 if (selinux_skb_peerlbl_sid(skb, family, &peer_sid))
4709 return NF_DROP;
4710 } else {
4711 secmark_perm = PACKET__SEND;
4712 peer_sid = SECINITSID_KERNEL;
4713 }
4714 } else {
4715 struct sk_security_struct *sksec = sk->sk_security;
4716 peer_sid = sksec->sid;
4717 secmark_perm = PACKET__SEND;
4718 }
4719
4720 ad.type = LSM_AUDIT_DATA_NET;
4721 ad.u.net = &net;
4722 ad.u.net->netif = ifindex;
4723 ad.u.net->family = family;
4724 if (selinux_parse_skb(skb, &ad, &addrp, 0, NULL))
4725 return NF_DROP;
4726
4727 if (secmark_active)
4728 if (avc_has_perm(peer_sid, skb->secmark,
4729 SECCLASS_PACKET, secmark_perm, &ad))
4730 return NF_DROP_ERR(-ECONNREFUSED);
4731
4732 if (peerlbl_active) {
4733 u32 if_sid;
4734 u32 node_sid;
4735
4736 if (sel_netif_sid(ifindex, &if_sid))
4737 return NF_DROP;
4738 if (avc_has_perm(peer_sid, if_sid,
4739 SECCLASS_NETIF, NETIF__EGRESS, &ad))
4740 return NF_DROP_ERR(-ECONNREFUSED);
4741
4742 if (sel_netnode_sid(addrp, family, &node_sid))
4743 return NF_DROP;
4744 if (avc_has_perm(peer_sid, node_sid,
4745 SECCLASS_NODE, NODE__SENDTO, &ad))
4746 return NF_DROP_ERR(-ECONNREFUSED);
4747 }
4748
4749 return NF_ACCEPT;
4750 }
4751
4752 static unsigned int selinux_ipv4_postroute(unsigned int hooknum,
4753 struct sk_buff *skb,
4754 const struct net_device *in,
4755 const struct net_device *out,
4756 int (*okfn)(struct sk_buff *))
4757 {
4758 return selinux_ip_postroute(skb, out->ifindex, PF_INET);
4759 }
4760
4761 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
4762 static unsigned int selinux_ipv6_postroute(unsigned int hooknum,
4763 struct sk_buff *skb,
4764 const struct net_device *in,
4765 const struct net_device *out,
4766 int (*okfn)(struct sk_buff *))
4767 {
4768 return selinux_ip_postroute(skb, out->ifindex, PF_INET6);
4769 }
4770 #endif /* IPV6 */
4771
4772 #endif /* CONFIG_NETFILTER */
4773
4774 static int selinux_netlink_send(struct sock *sk, struct sk_buff *skb)
4775 {
4776 int err;
4777
4778 err = cap_netlink_send(sk, skb);
4779 if (err)
4780 return err;
4781
4782 return selinux_nlmsg_perm(sk, skb);
4783 }
4784
4785 static int ipc_alloc_security(struct task_struct *task,
4786 struct kern_ipc_perm *perm,
4787 u16 sclass)
4788 {
4789 struct ipc_security_struct *isec;
4790 u32 sid;
4791
4792 isec = kzalloc(sizeof(struct ipc_security_struct), GFP_KERNEL);
4793 if (!isec)
4794 return -ENOMEM;
4795
4796 sid = task_sid(task);
4797 isec->sclass = sclass;
4798 isec->sid = sid;
4799 perm->security = isec;
4800
4801 return 0;
4802 }
4803
4804 static void ipc_free_security(struct kern_ipc_perm *perm)
4805 {
4806 struct ipc_security_struct *isec = perm->security;
4807 perm->security = NULL;
4808 kfree(isec);
4809 }
4810
4811 static int msg_msg_alloc_security(struct msg_msg *msg)
4812 {
4813 struct msg_security_struct *msec;
4814
4815 msec = kzalloc(sizeof(struct msg_security_struct), GFP_KERNEL);
4816 if (!msec)
4817 return -ENOMEM;
4818
4819 msec->sid = SECINITSID_UNLABELED;
4820 msg->security = msec;
4821
4822 return 0;
4823 }
4824
4825 static void msg_msg_free_security(struct msg_msg *msg)
4826 {
4827 struct msg_security_struct *msec = msg->security;
4828
4829 msg->security = NULL;
4830 kfree(msec);
4831 }
4832
4833 static int ipc_has_perm(struct kern_ipc_perm *ipc_perms,
4834 u32 perms)
4835 {
4836 struct ipc_security_struct *isec;
4837 struct common_audit_data ad;
4838 u32 sid = current_sid();
4839
4840 isec = ipc_perms->security;
4841
4842 ad.type = LSM_AUDIT_DATA_IPC;
4843 ad.u.ipc_id = ipc_perms->key;
4844
4845 return avc_has_perm(sid, isec->sid, isec->sclass, perms, &ad);
4846 }
4847
4848 static int selinux_msg_msg_alloc_security(struct msg_msg *msg)
4849 {
4850 return msg_msg_alloc_security(msg);
4851 }
4852
4853 static void selinux_msg_msg_free_security(struct msg_msg *msg)
4854 {
4855 msg_msg_free_security(msg);
4856 }
4857
4858 /* message queue security operations */
4859 static int selinux_msg_queue_alloc_security(struct msg_queue *msq)
4860 {
4861 struct ipc_security_struct *isec;
4862 struct common_audit_data ad;
4863 u32 sid = current_sid();
4864 int rc;
4865
4866 rc = ipc_alloc_security(current, &msq->q_perm, SECCLASS_MSGQ);
4867 if (rc)
4868 return rc;
4869
4870 isec = msq->q_perm.security;
4871
4872 ad.type = LSM_AUDIT_DATA_IPC;
4873 ad.u.ipc_id = msq->q_perm.key;
4874
4875 rc = avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
4876 MSGQ__CREATE, &ad);
4877 if (rc) {
4878 ipc_free_security(&msq->q_perm);
4879 return rc;
4880 }
4881 return 0;
4882 }
4883
4884 static void selinux_msg_queue_free_security(struct msg_queue *msq)
4885 {
4886 ipc_free_security(&msq->q_perm);
4887 }
4888
4889 static int selinux_msg_queue_associate(struct msg_queue *msq, int msqflg)
4890 {
4891 struct ipc_security_struct *isec;
4892 struct common_audit_data ad;
4893 u32 sid = current_sid();
4894
4895 isec = msq->q_perm.security;
4896
4897 ad.type = LSM_AUDIT_DATA_IPC;
4898 ad.u.ipc_id = msq->q_perm.key;
4899
4900 return avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
4901 MSGQ__ASSOCIATE, &ad);
4902 }
4903
4904 static int selinux_msg_queue_msgctl(struct msg_queue *msq, int cmd)
4905 {
4906 int err;
4907 int perms;
4908
4909 switch (cmd) {
4910 case IPC_INFO:
4911 case MSG_INFO:
4912 /* No specific object, just general system-wide information. */
4913 return task_has_system(current, SYSTEM__IPC_INFO);
4914 case IPC_STAT:
4915 case MSG_STAT:
4916 perms = MSGQ__GETATTR | MSGQ__ASSOCIATE;
4917 break;
4918 case IPC_SET:
4919 perms = MSGQ__SETATTR;
4920 break;
4921 case IPC_RMID:
4922 perms = MSGQ__DESTROY;
4923 break;
4924 default:
4925 return 0;
4926 }
4927
4928 err = ipc_has_perm(&msq->q_perm, perms);
4929 return err;
4930 }
4931
4932 static int selinux_msg_queue_msgsnd(struct msg_queue *msq, struct msg_msg *msg, int msqflg)
4933 {
4934 struct ipc_security_struct *isec;
4935 struct msg_security_struct *msec;
4936 struct common_audit_data ad;
4937 u32 sid = current_sid();
4938 int rc;
4939
4940 isec = msq->q_perm.security;
4941 msec = msg->security;
4942
4943 /*
4944 * First time through, need to assign label to the message
4945 */
4946 if (msec->sid == SECINITSID_UNLABELED) {
4947 /*
4948 * Compute new sid based on current process and
4949 * message queue this message will be stored in
4950 */
4951 rc = security_transition_sid(sid, isec->sid, SECCLASS_MSG,
4952 NULL, &msec->sid);
4953 if (rc)
4954 return rc;
4955 }
4956
4957 ad.type = LSM_AUDIT_DATA_IPC;
4958 ad.u.ipc_id = msq->q_perm.key;
4959
4960 /* Can this process write to the queue? */
4961 rc = avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
4962 MSGQ__WRITE, &ad);
4963 if (!rc)
4964 /* Can this process send the message */
4965 rc = avc_has_perm(sid, msec->sid, SECCLASS_MSG,
4966 MSG__SEND, &ad);
4967 if (!rc)
4968 /* Can the message be put in the queue? */
4969 rc = avc_has_perm(msec->sid, isec->sid, SECCLASS_MSGQ,
4970 MSGQ__ENQUEUE, &ad);
4971
4972 return rc;
4973 }
4974
4975 static int selinux_msg_queue_msgrcv(struct msg_queue *msq, struct msg_msg *msg,
4976 struct task_struct *target,
4977 long type, int mode)
4978 {
4979 struct ipc_security_struct *isec;
4980 struct msg_security_struct *msec;
4981 struct common_audit_data ad;
4982 u32 sid = task_sid(target);
4983 int rc;
4984
4985 isec = msq->q_perm.security;
4986 msec = msg->security;
4987
4988 ad.type = LSM_AUDIT_DATA_IPC;
4989 ad.u.ipc_id = msq->q_perm.key;
4990
4991 rc = avc_has_perm(sid, isec->sid,
4992 SECCLASS_MSGQ, MSGQ__READ, &ad);
4993 if (!rc)
4994 rc = avc_has_perm(sid, msec->sid,
4995 SECCLASS_MSG, MSG__RECEIVE, &ad);
4996 return rc;
4997 }
4998
4999 /* Shared Memory security operations */
5000 static int selinux_shm_alloc_security(struct shmid_kernel *shp)
5001 {
5002 struct ipc_security_struct *isec;
5003 struct common_audit_data ad;
5004 u32 sid = current_sid();
5005 int rc;
5006
5007 rc = ipc_alloc_security(current, &shp->shm_perm, SECCLASS_SHM);
5008 if (rc)
5009 return rc;
5010
5011 isec = shp->shm_perm.security;
5012
5013 ad.type = LSM_AUDIT_DATA_IPC;
5014 ad.u.ipc_id = shp->shm_perm.key;
5015
5016 rc = avc_has_perm(sid, isec->sid, SECCLASS_SHM,
5017 SHM__CREATE, &ad);
5018 if (rc) {
5019 ipc_free_security(&shp->shm_perm);
5020 return rc;
5021 }
5022 return 0;
5023 }
5024
5025 static void selinux_shm_free_security(struct shmid_kernel *shp)
5026 {
5027 ipc_free_security(&shp->shm_perm);
5028 }
5029
5030 static int selinux_shm_associate(struct shmid_kernel *shp, int shmflg)
5031 {
5032 struct ipc_security_struct *isec;
5033 struct common_audit_data ad;
5034 u32 sid = current_sid();
5035
5036 isec = shp->shm_perm.security;
5037
5038 ad.type = LSM_AUDIT_DATA_IPC;
5039 ad.u.ipc_id = shp->shm_perm.key;
5040
5041 return avc_has_perm(sid, isec->sid, SECCLASS_SHM,
5042 SHM__ASSOCIATE, &ad);
5043 }
5044
5045 /* Note, at this point, shp is locked down */
5046 static int selinux_shm_shmctl(struct shmid_kernel *shp, int cmd)
5047 {
5048 int perms;
5049 int err;
5050
5051 switch (cmd) {
5052 case IPC_INFO:
5053 case SHM_INFO:
5054 /* No specific object, just general system-wide information. */
5055 return task_has_system(current, SYSTEM__IPC_INFO);
5056 case IPC_STAT:
5057 case SHM_STAT:
5058 perms = SHM__GETATTR | SHM__ASSOCIATE;
5059 break;
5060 case IPC_SET:
5061 perms = SHM__SETATTR;
5062 break;
5063 case SHM_LOCK:
5064 case SHM_UNLOCK:
5065 perms = SHM__LOCK;
5066 break;
5067 case IPC_RMID:
5068 perms = SHM__DESTROY;
5069 break;
5070 default:
5071 return 0;
5072 }
5073
5074 err = ipc_has_perm(&shp->shm_perm, perms);
5075 return err;
5076 }
5077
5078 static int selinux_shm_shmat(struct shmid_kernel *shp,
5079 char __user *shmaddr, int shmflg)
5080 {
5081 u32 perms;
5082
5083 if (shmflg & SHM_RDONLY)
5084 perms = SHM__READ;
5085 else
5086 perms = SHM__READ | SHM__WRITE;
5087
5088 return ipc_has_perm(&shp->shm_perm, perms);
5089 }
5090
5091 /* Semaphore security operations */
5092 static int selinux_sem_alloc_security(struct sem_array *sma)
5093 {
5094 struct ipc_security_struct *isec;
5095 struct common_audit_data ad;
5096 u32 sid = current_sid();
5097 int rc;
5098
5099 rc = ipc_alloc_security(current, &sma->sem_perm, SECCLASS_SEM);
5100 if (rc)
5101 return rc;
5102
5103 isec = sma->sem_perm.security;
5104
5105 ad.type = LSM_AUDIT_DATA_IPC;
5106 ad.u.ipc_id = sma->sem_perm.key;
5107
5108 rc = avc_has_perm(sid, isec->sid, SECCLASS_SEM,
5109 SEM__CREATE, &ad);
5110 if (rc) {
5111 ipc_free_security(&sma->sem_perm);
5112 return rc;
5113 }
5114 return 0;
5115 }
5116
5117 static void selinux_sem_free_security(struct sem_array *sma)
5118 {
5119 ipc_free_security(&sma->sem_perm);
5120 }
5121
5122 static int selinux_sem_associate(struct sem_array *sma, int semflg)
5123 {
5124 struct ipc_security_struct *isec;
5125 struct common_audit_data ad;
5126 u32 sid = current_sid();
5127
5128 isec = sma->sem_perm.security;
5129
5130 ad.type = LSM_AUDIT_DATA_IPC;
5131 ad.u.ipc_id = sma->sem_perm.key;
5132
5133 return avc_has_perm(sid, isec->sid, SECCLASS_SEM,
5134 SEM__ASSOCIATE, &ad);
5135 }
5136
5137 /* Note, at this point, sma is locked down */
5138 static int selinux_sem_semctl(struct sem_array *sma, int cmd)
5139 {
5140 int err;
5141 u32 perms;
5142
5143 switch (cmd) {
5144 case IPC_INFO:
5145 case SEM_INFO:
5146 /* No specific object, just general system-wide information. */
5147 return task_has_system(current, SYSTEM__IPC_INFO);
5148 case GETPID:
5149 case GETNCNT:
5150 case GETZCNT:
5151 perms = SEM__GETATTR;
5152 break;
5153 case GETVAL:
5154 case GETALL:
5155 perms = SEM__READ;
5156 break;
5157 case SETVAL:
5158 case SETALL:
5159 perms = SEM__WRITE;
5160 break;
5161 case IPC_RMID:
5162 perms = SEM__DESTROY;
5163 break;
5164 case IPC_SET:
5165 perms = SEM__SETATTR;
5166 break;
5167 case IPC_STAT:
5168 case SEM_STAT:
5169 perms = SEM__GETATTR | SEM__ASSOCIATE;
5170 break;
5171 default:
5172 return 0;
5173 }
5174
5175 err = ipc_has_perm(&sma->sem_perm, perms);
5176 return err;
5177 }
5178
5179 static int selinux_sem_semop(struct sem_array *sma,
5180 struct sembuf *sops, unsigned nsops, int alter)
5181 {
5182 u32 perms;
5183
5184 if (alter)
5185 perms = SEM__READ | SEM__WRITE;
5186 else
5187 perms = SEM__READ;
5188
5189 return ipc_has_perm(&sma->sem_perm, perms);
5190 }
5191
5192 static int selinux_ipc_permission(struct kern_ipc_perm *ipcp, short flag)
5193 {
5194 u32 av = 0;
5195
5196 av = 0;
5197 if (flag & S_IRUGO)
5198 av |= IPC__UNIX_READ;
5199 if (flag & S_IWUGO)
5200 av |= IPC__UNIX_WRITE;
5201
5202 if (av == 0)
5203 return 0;
5204
5205 return ipc_has_perm(ipcp, av);
5206 }
5207
5208 static void selinux_ipc_getsecid(struct kern_ipc_perm *ipcp, u32 *secid)
5209 {
5210 struct ipc_security_struct *isec = ipcp->security;
5211 *secid = isec->sid;
5212 }
5213
5214 static void selinux_d_instantiate(struct dentry *dentry, struct inode *inode)
5215 {
5216 if (inode)
5217 inode_doinit_with_dentry(inode, dentry);
5218 }
5219
5220 static int selinux_getprocattr(struct task_struct *p,
5221 char *name, char **value)
5222 {
5223 const struct task_security_struct *__tsec;
5224 u32 sid;
5225 int error;
5226 unsigned len;
5227
5228 if (current != p) {
5229 error = current_has_perm(p, PROCESS__GETATTR);
5230 if (error)
5231 return error;
5232 }
5233
5234 rcu_read_lock();
5235 __tsec = __task_cred(p)->security;
5236
5237 if (!strcmp(name, "current"))
5238 sid = __tsec->sid;
5239 else if (!strcmp(name, "prev"))
5240 sid = __tsec->osid;
5241 else if (!strcmp(name, "exec"))
5242 sid = __tsec->exec_sid;
5243 else if (!strcmp(name, "fscreate"))
5244 sid = __tsec->create_sid;
5245 else if (!strcmp(name, "keycreate"))
5246 sid = __tsec->keycreate_sid;
5247 else if (!strcmp(name, "sockcreate"))
5248 sid = __tsec->sockcreate_sid;
5249 else
5250 goto invalid;
5251 rcu_read_unlock();
5252
5253 if (!sid)
5254 return 0;
5255
5256 error = security_sid_to_context(sid, value, &len);
5257 if (error)
5258 return error;
5259 return len;
5260
5261 invalid:
5262 rcu_read_unlock();
5263 return -EINVAL;
5264 }
5265
5266 static int selinux_setprocattr(struct task_struct *p,
5267 char *name, void *value, size_t size)
5268 {
5269 struct task_security_struct *tsec;
5270 struct task_struct *tracer;
5271 struct cred *new;
5272 u32 sid = 0, ptsid;
5273 int error;
5274 char *str = value;
5275
5276 if (current != p) {
5277 /* SELinux only allows a process to change its own
5278 security attributes. */
5279 return -EACCES;
5280 }
5281
5282 /*
5283 * Basic control over ability to set these attributes at all.
5284 * current == p, but we'll pass them separately in case the
5285 * above restriction is ever removed.
5286 */
5287 if (!strcmp(name, "exec"))
5288 error = current_has_perm(p, PROCESS__SETEXEC);
5289 else if (!strcmp(name, "fscreate"))
5290 error = current_has_perm(p, PROCESS__SETFSCREATE);
5291 else if (!strcmp(name, "keycreate"))
5292 error = current_has_perm(p, PROCESS__SETKEYCREATE);
5293 else if (!strcmp(name, "sockcreate"))
5294 error = current_has_perm(p, PROCESS__SETSOCKCREATE);
5295 else if (!strcmp(name, "current"))
5296 error = current_has_perm(p, PROCESS__SETCURRENT);
5297 else
5298 error = -EINVAL;
5299 if (error)
5300 return error;
5301
5302 /* Obtain a SID for the context, if one was specified. */
5303 if (size && str[1] && str[1] != '\n') {
5304 if (str[size-1] == '\n') {
5305 str[size-1] = 0;
5306 size--;
5307 }
5308 error = security_context_to_sid(value, size, &sid);
5309 if (error == -EINVAL && !strcmp(name, "fscreate")) {
5310 if (!capable(CAP_MAC_ADMIN)) {
5311 struct audit_buffer *ab;
5312 size_t audit_size;
5313
5314 /* We strip a nul only if it is at the end, otherwise the
5315 * context contains a nul and we should audit that */
5316 if (str[size - 1] == '\0')
5317 audit_size = size - 1;
5318 else
5319 audit_size = size;
5320 ab = audit_log_start(current->audit_context, GFP_ATOMIC, AUDIT_SELINUX_ERR);
5321 audit_log_format(ab, "op=fscreate invalid_context=");
5322 audit_log_n_untrustedstring(ab, value, audit_size);
5323 audit_log_end(ab);
5324
5325 return error;
5326 }
5327 error = security_context_to_sid_force(value, size,
5328 &sid);
5329 }
5330 if (error)
5331 return error;
5332 }
5333
5334 new = prepare_creds();
5335 if (!new)
5336 return -ENOMEM;
5337
5338 /* Permission checking based on the specified context is
5339 performed during the actual operation (execve,
5340 open/mkdir/...), when we know the full context of the
5341 operation. See selinux_bprm_set_creds for the execve
5342 checks and may_create for the file creation checks. The
5343 operation will then fail if the context is not permitted. */
5344 tsec = new->security;
5345 if (!strcmp(name, "exec")) {
5346 tsec->exec_sid = sid;
5347 } else if (!strcmp(name, "fscreate")) {
5348 tsec->create_sid = sid;
5349 } else if (!strcmp(name, "keycreate")) {
5350 error = may_create_key(sid, p);
5351 if (error)
5352 goto abort_change;
5353 tsec->keycreate_sid = sid;
5354 } else if (!strcmp(name, "sockcreate")) {
5355 tsec->sockcreate_sid = sid;
5356 } else if (!strcmp(name, "current")) {
5357 error = -EINVAL;
5358 if (sid == 0)
5359 goto abort_change;
5360
5361 /* Only allow single threaded processes to change context */
5362 error = -EPERM;
5363 if (!current_is_single_threaded()) {
5364 error = security_bounded_transition(tsec->sid, sid);
5365 if (error)
5366 goto abort_change;
5367 }
5368
5369 /* Check permissions for the transition. */
5370 error = avc_has_perm(tsec->sid, sid, SECCLASS_PROCESS,
5371 PROCESS__DYNTRANSITION, NULL);
5372 if (error)
5373 goto abort_change;
5374
5375 /* Check for ptracing, and update the task SID if ok.
5376 Otherwise, leave SID unchanged and fail. */
5377 ptsid = 0;
5378 task_lock(p);
5379 tracer = ptrace_parent(p);
5380 if (tracer)
5381 ptsid = task_sid(tracer);
5382 task_unlock(p);
5383
5384 if (tracer) {
5385 error = avc_has_perm(ptsid, sid, SECCLASS_PROCESS,
5386 PROCESS__PTRACE, NULL);
5387 if (error)
5388 goto abort_change;
5389 }
5390
5391 tsec->sid = sid;
5392 } else {
5393 error = -EINVAL;
5394 goto abort_change;
5395 }
5396
5397 commit_creds(new);
5398 return size;
5399
5400 abort_change:
5401 abort_creds(new);
5402 return error;
5403 }
5404
5405 static int selinux_secid_to_secctx(u32 secid, char **secdata, u32 *seclen)
5406 {
5407 return security_sid_to_context(secid, secdata, seclen);
5408 }
5409
5410 static int selinux_secctx_to_secid(const char *secdata, u32 seclen, u32 *secid)
5411 {
5412 return security_context_to_sid(secdata, seclen, secid);
5413 }
5414
5415 static void selinux_release_secctx(char *secdata, u32 seclen)
5416 {
5417 kfree(secdata);
5418 }
5419
5420 /*
5421 * called with inode->i_mutex locked
5422 */
5423 static int selinux_inode_notifysecctx(struct inode *inode, void *ctx, u32 ctxlen)
5424 {
5425 return selinux_inode_setsecurity(inode, XATTR_SELINUX_SUFFIX, ctx, ctxlen, 0);
5426 }
5427
5428 /*
5429 * called with inode->i_mutex locked
5430 */
5431 static int selinux_inode_setsecctx(struct dentry *dentry, void *ctx, u32 ctxlen)
5432 {
5433 return __vfs_setxattr_noperm(dentry, XATTR_NAME_SELINUX, ctx, ctxlen, 0);
5434 }
5435
5436 static int selinux_inode_getsecctx(struct inode *inode, void **ctx, u32 *ctxlen)
5437 {
5438 int len = 0;
5439 len = selinux_inode_getsecurity(inode, XATTR_SELINUX_SUFFIX,
5440 ctx, true);
5441 if (len < 0)
5442 return len;
5443 *ctxlen = len;
5444 return 0;
5445 }
5446 #ifdef CONFIG_KEYS
5447
5448 static int selinux_key_alloc(struct key *k, const struct cred *cred,
5449 unsigned long flags)
5450 {
5451 const struct task_security_struct *tsec;
5452 struct key_security_struct *ksec;
5453
5454 ksec = kzalloc(sizeof(struct key_security_struct), GFP_KERNEL);
5455 if (!ksec)
5456 return -ENOMEM;
5457
5458 tsec = cred->security;
5459 if (tsec->keycreate_sid)
5460 ksec->sid = tsec->keycreate_sid;
5461 else
5462 ksec->sid = tsec->sid;
5463
5464 k->security = ksec;
5465 return 0;
5466 }
5467
5468 static void selinux_key_free(struct key *k)
5469 {
5470 struct key_security_struct *ksec = k->security;
5471
5472 k->security = NULL;
5473 kfree(ksec);
5474 }
5475
5476 static int selinux_key_permission(key_ref_t key_ref,
5477 const struct cred *cred,
5478 key_perm_t perm)
5479 {
5480 struct key *key;
5481 struct key_security_struct *ksec;
5482 u32 sid;
5483
5484 /* if no specific permissions are requested, we skip the
5485 permission check. No serious, additional covert channels
5486 appear to be created. */
5487 if (perm == 0)
5488 return 0;
5489
5490 sid = cred_sid(cred);
5491
5492 key = key_ref_to_ptr(key_ref);
5493 ksec = key->security;
5494
5495 return avc_has_perm(sid, ksec->sid, SECCLASS_KEY, perm, NULL);
5496 }
5497
5498 static int selinux_key_getsecurity(struct key *key, char **_buffer)
5499 {
5500 struct key_security_struct *ksec = key->security;
5501 char *context = NULL;
5502 unsigned len;
5503 int rc;
5504
5505 rc = security_sid_to_context(ksec->sid, &context, &len);
5506 if (!rc)
5507 rc = len;
5508 *_buffer = context;
5509 return rc;
5510 }
5511
5512 #endif
5513
5514 static struct security_operations selinux_ops = {
5515 .name = "selinux",
5516
5517 .ptrace_access_check = selinux_ptrace_access_check,
5518 .ptrace_traceme = selinux_ptrace_traceme,
5519 .capget = selinux_capget,
5520 .capset = selinux_capset,
5521 .capable = selinux_capable,
5522 .quotactl = selinux_quotactl,
5523 .quota_on = selinux_quota_on,
5524 .syslog = selinux_syslog,
5525 .vm_enough_memory = selinux_vm_enough_memory,
5526
5527 .netlink_send = selinux_netlink_send,
5528
5529 .bprm_set_creds = selinux_bprm_set_creds,
5530 .bprm_committing_creds = selinux_bprm_committing_creds,
5531 .bprm_committed_creds = selinux_bprm_committed_creds,
5532 .bprm_secureexec = selinux_bprm_secureexec,
5533
5534 .sb_alloc_security = selinux_sb_alloc_security,
5535 .sb_free_security = selinux_sb_free_security,
5536 .sb_copy_data = selinux_sb_copy_data,
5537 .sb_remount = selinux_sb_remount,
5538 .sb_kern_mount = selinux_sb_kern_mount,
5539 .sb_show_options = selinux_sb_show_options,
5540 .sb_statfs = selinux_sb_statfs,
5541 .sb_mount = selinux_mount,
5542 .sb_umount = selinux_umount,
5543 .sb_set_mnt_opts = selinux_set_mnt_opts,
5544 .sb_clone_mnt_opts = selinux_sb_clone_mnt_opts,
5545 .sb_parse_opts_str = selinux_parse_opts_str,
5546
5547
5548 .inode_alloc_security = selinux_inode_alloc_security,
5549 .inode_free_security = selinux_inode_free_security,
5550 .inode_init_security = selinux_inode_init_security,
5551 .inode_create = selinux_inode_create,
5552 .inode_link = selinux_inode_link,
5553 .inode_unlink = selinux_inode_unlink,
5554 .inode_symlink = selinux_inode_symlink,
5555 .inode_mkdir = selinux_inode_mkdir,
5556 .inode_rmdir = selinux_inode_rmdir,
5557 .inode_mknod = selinux_inode_mknod,
5558 .inode_rename = selinux_inode_rename,
5559 .inode_readlink = selinux_inode_readlink,
5560 .inode_follow_link = selinux_inode_follow_link,
5561 .inode_permission = selinux_inode_permission,
5562 .inode_setattr = selinux_inode_setattr,
5563 .inode_getattr = selinux_inode_getattr,
5564 .inode_setxattr = selinux_inode_setxattr,
5565 .inode_post_setxattr = selinux_inode_post_setxattr,
5566 .inode_getxattr = selinux_inode_getxattr,
5567 .inode_listxattr = selinux_inode_listxattr,
5568 .inode_removexattr = selinux_inode_removexattr,
5569 .inode_getsecurity = selinux_inode_getsecurity,
5570 .inode_setsecurity = selinux_inode_setsecurity,
5571 .inode_listsecurity = selinux_inode_listsecurity,
5572 .inode_getsecid = selinux_inode_getsecid,
5573
5574 .file_permission = selinux_file_permission,
5575 .file_alloc_security = selinux_file_alloc_security,
5576 .file_free_security = selinux_file_free_security,
5577 .file_ioctl = selinux_file_ioctl,
5578 .mmap_file = selinux_mmap_file,
5579 .mmap_addr = selinux_mmap_addr,
5580 .file_mprotect = selinux_file_mprotect,
5581 .file_lock = selinux_file_lock,
5582 .file_fcntl = selinux_file_fcntl,
5583 .file_set_fowner = selinux_file_set_fowner,
5584 .file_send_sigiotask = selinux_file_send_sigiotask,
5585 .file_receive = selinux_file_receive,
5586
5587 .file_open = selinux_file_open,
5588
5589 .task_create = selinux_task_create,
5590 .cred_alloc_blank = selinux_cred_alloc_blank,
5591 .cred_free = selinux_cred_free,
5592 .cred_prepare = selinux_cred_prepare,
5593 .cred_transfer = selinux_cred_transfer,
5594 .kernel_act_as = selinux_kernel_act_as,
5595 .kernel_create_files_as = selinux_kernel_create_files_as,
5596 .kernel_module_request = selinux_kernel_module_request,
5597 .task_setpgid = selinux_task_setpgid,
5598 .task_getpgid = selinux_task_getpgid,
5599 .task_getsid = selinux_task_getsid,
5600 .task_getsecid = selinux_task_getsecid,
5601 .task_setnice = selinux_task_setnice,
5602 .task_setioprio = selinux_task_setioprio,
5603 .task_getioprio = selinux_task_getioprio,
5604 .task_setrlimit = selinux_task_setrlimit,
5605 .task_setscheduler = selinux_task_setscheduler,
5606 .task_getscheduler = selinux_task_getscheduler,
5607 .task_movememory = selinux_task_movememory,
5608 .task_kill = selinux_task_kill,
5609 .task_wait = selinux_task_wait,
5610 .task_to_inode = selinux_task_to_inode,
5611
5612 .ipc_permission = selinux_ipc_permission,
5613 .ipc_getsecid = selinux_ipc_getsecid,
5614
5615 .msg_msg_alloc_security = selinux_msg_msg_alloc_security,
5616 .msg_msg_free_security = selinux_msg_msg_free_security,
5617
5618 .msg_queue_alloc_security = selinux_msg_queue_alloc_security,
5619 .msg_queue_free_security = selinux_msg_queue_free_security,
5620 .msg_queue_associate = selinux_msg_queue_associate,
5621 .msg_queue_msgctl = selinux_msg_queue_msgctl,
5622 .msg_queue_msgsnd = selinux_msg_queue_msgsnd,
5623 .msg_queue_msgrcv = selinux_msg_queue_msgrcv,
5624
5625 .shm_alloc_security = selinux_shm_alloc_security,
5626 .shm_free_security = selinux_shm_free_security,
5627 .shm_associate = selinux_shm_associate,
5628 .shm_shmctl = selinux_shm_shmctl,
5629 .shm_shmat = selinux_shm_shmat,
5630
5631 .sem_alloc_security = selinux_sem_alloc_security,
5632 .sem_free_security = selinux_sem_free_security,
5633 .sem_associate = selinux_sem_associate,
5634 .sem_semctl = selinux_sem_semctl,
5635 .sem_semop = selinux_sem_semop,
5636
5637 .d_instantiate = selinux_d_instantiate,
5638
5639 .getprocattr = selinux_getprocattr,
5640 .setprocattr = selinux_setprocattr,
5641
5642 .secid_to_secctx = selinux_secid_to_secctx,
5643 .secctx_to_secid = selinux_secctx_to_secid,
5644 .release_secctx = selinux_release_secctx,
5645 .inode_notifysecctx = selinux_inode_notifysecctx,
5646 .inode_setsecctx = selinux_inode_setsecctx,
5647 .inode_getsecctx = selinux_inode_getsecctx,
5648
5649 .unix_stream_connect = selinux_socket_unix_stream_connect,
5650 .unix_may_send = selinux_socket_unix_may_send,
5651
5652 .socket_create = selinux_socket_create,
5653 .socket_post_create = selinux_socket_post_create,
5654 .socket_bind = selinux_socket_bind,
5655 .socket_connect = selinux_socket_connect,
5656 .socket_listen = selinux_socket_listen,
5657 .socket_accept = selinux_socket_accept,
5658 .socket_sendmsg = selinux_socket_sendmsg,
5659 .socket_recvmsg = selinux_socket_recvmsg,
5660 .socket_getsockname = selinux_socket_getsockname,
5661 .socket_getpeername = selinux_socket_getpeername,
5662 .socket_getsockopt = selinux_socket_getsockopt,
5663 .socket_setsockopt = selinux_socket_setsockopt,
5664 .socket_shutdown = selinux_socket_shutdown,
5665 .socket_sock_rcv_skb = selinux_socket_sock_rcv_skb,
5666 .socket_getpeersec_stream = selinux_socket_getpeersec_stream,
5667 .socket_getpeersec_dgram = selinux_socket_getpeersec_dgram,
5668 .sk_alloc_security = selinux_sk_alloc_security,
5669 .sk_free_security = selinux_sk_free_security,
5670 .sk_clone_security = selinux_sk_clone_security,
5671 .sk_getsecid = selinux_sk_getsecid,
5672 .sock_graft = selinux_sock_graft,
5673 .inet_conn_request = selinux_inet_conn_request,
5674 .inet_csk_clone = selinux_inet_csk_clone,
5675 .inet_conn_established = selinux_inet_conn_established,
5676 .secmark_relabel_packet = selinux_secmark_relabel_packet,
5677 .secmark_refcount_inc = selinux_secmark_refcount_inc,
5678 .secmark_refcount_dec = selinux_secmark_refcount_dec,
5679 .req_classify_flow = selinux_req_classify_flow,
5680 .tun_dev_create = selinux_tun_dev_create,
5681 .tun_dev_post_create = selinux_tun_dev_post_create,
5682 .tun_dev_attach = selinux_tun_dev_attach,
5683
5684 #ifdef CONFIG_SECURITY_NETWORK_XFRM
5685 .xfrm_policy_alloc_security = selinux_xfrm_policy_alloc,
5686 .xfrm_policy_clone_security = selinux_xfrm_policy_clone,
5687 .xfrm_policy_free_security = selinux_xfrm_policy_free,
5688 .xfrm_policy_delete_security = selinux_xfrm_policy_delete,
5689 .xfrm_state_alloc_security = selinux_xfrm_state_alloc,
5690 .xfrm_state_free_security = selinux_xfrm_state_free,
5691 .xfrm_state_delete_security = selinux_xfrm_state_delete,
5692 .xfrm_policy_lookup = selinux_xfrm_policy_lookup,
5693 .xfrm_state_pol_flow_match = selinux_xfrm_state_pol_flow_match,
5694 .xfrm_decode_session = selinux_xfrm_decode_session,
5695 #endif
5696
5697 #ifdef CONFIG_KEYS
5698 .key_alloc = selinux_key_alloc,
5699 .key_free = selinux_key_free,
5700 .key_permission = selinux_key_permission,
5701 .key_getsecurity = selinux_key_getsecurity,
5702 #endif
5703
5704 #ifdef CONFIG_AUDIT
5705 .audit_rule_init = selinux_audit_rule_init,
5706 .audit_rule_known = selinux_audit_rule_known,
5707 .audit_rule_match = selinux_audit_rule_match,
5708 .audit_rule_free = selinux_audit_rule_free,
5709 #endif
5710 };
5711
5712 static __init int selinux_init(void)
5713 {
5714 if (!security_module_enable(&selinux_ops)) {
5715 selinux_enabled = 0;
5716 return 0;
5717 }
5718
5719 if (!selinux_enabled) {
5720 printk(KERN_INFO "SELinux: Disabled at boot.\n");
5721 return 0;
5722 }
5723
5724 printk(KERN_INFO "SELinux: Initializing.\n");
5725
5726 /* Set the security state for the initial task. */
5727 cred_init_security();
5728
5729 default_noexec = !(VM_DATA_DEFAULT_FLAGS & VM_EXEC);
5730
5731 sel_inode_cache = kmem_cache_create("selinux_inode_security",
5732 sizeof(struct inode_security_struct),
5733 0, SLAB_PANIC, NULL);
5734 avc_init();
5735
5736 if (register_security(&selinux_ops))
5737 panic("SELinux: Unable to register with kernel.\n");
5738
5739 if (selinux_enforcing)
5740 printk(KERN_DEBUG "SELinux: Starting in enforcing mode\n");
5741 else
5742 printk(KERN_DEBUG "SELinux: Starting in permissive mode\n");
5743
5744 return 0;
5745 }
5746
5747 static void delayed_superblock_init(struct super_block *sb, void *unused)
5748 {
5749 superblock_doinit(sb, NULL);
5750 }
5751
5752 void selinux_complete_init(void)
5753 {
5754 printk(KERN_DEBUG "SELinux: Completing initialization.\n");
5755
5756 /* Set up any superblocks initialized prior to the policy load. */
5757 printk(KERN_DEBUG "SELinux: Setting up existing superblocks.\n");
5758 iterate_supers(delayed_superblock_init, NULL);
5759 }
5760
5761 /* SELinux requires early initialization in order to label
5762 all processes and objects when they are created. */
5763 security_initcall(selinux_init);
5764
5765 #if defined(CONFIG_NETFILTER)
5766
5767 static struct nf_hook_ops selinux_ipv4_ops[] = {
5768 {
5769 .hook = selinux_ipv4_postroute,
5770 .owner = THIS_MODULE,
5771 .pf = NFPROTO_IPV4,
5772 .hooknum = NF_INET_POST_ROUTING,
5773 .priority = NF_IP_PRI_SELINUX_LAST,
5774 },
5775 {
5776 .hook = selinux_ipv4_forward,
5777 .owner = THIS_MODULE,
5778 .pf = NFPROTO_IPV4,
5779 .hooknum = NF_INET_FORWARD,
5780 .priority = NF_IP_PRI_SELINUX_FIRST,
5781 },
5782 {
5783 .hook = selinux_ipv4_output,
5784 .owner = THIS_MODULE,
5785 .pf = NFPROTO_IPV4,
5786 .hooknum = NF_INET_LOCAL_OUT,
5787 .priority = NF_IP_PRI_SELINUX_FIRST,
5788 }
5789 };
5790
5791 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
5792
5793 static struct nf_hook_ops selinux_ipv6_ops[] = {
5794 {
5795 .hook = selinux_ipv6_postroute,
5796 .owner = THIS_MODULE,
5797 .pf = NFPROTO_IPV6,
5798 .hooknum = NF_INET_POST_ROUTING,
5799 .priority = NF_IP6_PRI_SELINUX_LAST,
5800 },
5801 {
5802 .hook = selinux_ipv6_forward,
5803 .owner = THIS_MODULE,
5804 .pf = NFPROTO_IPV6,
5805 .hooknum = NF_INET_FORWARD,
5806 .priority = NF_IP6_PRI_SELINUX_FIRST,
5807 }
5808 };
5809
5810 #endif /* IPV6 */
5811
5812 static int __init selinux_nf_ip_init(void)
5813 {
5814 int err = 0;
5815
5816 if (!selinux_enabled)
5817 goto out;
5818
5819 printk(KERN_DEBUG "SELinux: Registering netfilter hooks\n");
5820
5821 err = nf_register_hooks(selinux_ipv4_ops, ARRAY_SIZE(selinux_ipv4_ops));
5822 if (err)
5823 panic("SELinux: nf_register_hooks for IPv4: error %d\n", err);
5824
5825 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
5826 err = nf_register_hooks(selinux_ipv6_ops, ARRAY_SIZE(selinux_ipv6_ops));
5827 if (err)
5828 panic("SELinux: nf_register_hooks for IPv6: error %d\n", err);
5829 #endif /* IPV6 */
5830
5831 out:
5832 return err;
5833 }
5834
5835 __initcall(selinux_nf_ip_init);
5836
5837 #ifdef CONFIG_SECURITY_SELINUX_DISABLE
5838 static void selinux_nf_ip_exit(void)
5839 {
5840 printk(KERN_DEBUG "SELinux: Unregistering netfilter hooks\n");
5841
5842 nf_unregister_hooks(selinux_ipv4_ops, ARRAY_SIZE(selinux_ipv4_ops));
5843 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
5844 nf_unregister_hooks(selinux_ipv6_ops, ARRAY_SIZE(selinux_ipv6_ops));
5845 #endif /* IPV6 */
5846 }
5847 #endif
5848
5849 #else /* CONFIG_NETFILTER */
5850
5851 #ifdef CONFIG_SECURITY_SELINUX_DISABLE
5852 #define selinux_nf_ip_exit()
5853 #endif
5854
5855 #endif /* CONFIG_NETFILTER */
5856
5857 #ifdef CONFIG_SECURITY_SELINUX_DISABLE
5858 static int selinux_disabled;
5859
5860 int selinux_disable(void)
5861 {
5862 if (ss_initialized) {
5863 /* Not permitted after initial policy load. */
5864 return -EINVAL;
5865 }
5866
5867 if (selinux_disabled) {
5868 /* Only do this once. */
5869 return -EINVAL;
5870 }
5871
5872 printk(KERN_INFO "SELinux: Disabled at runtime.\n");
5873
5874 selinux_disabled = 1;
5875 selinux_enabled = 0;
5876
5877 reset_security_ops();
5878
5879 /* Try to destroy the avc node cache */
5880 avc_disable();
5881
5882 /* Unregister netfilter hooks. */
5883 selinux_nf_ip_exit();
5884
5885 /* Unregister selinuxfs. */
5886 exit_sel_fs();
5887
5888 return 0;
5889 }
5890 #endif
Linux 2.6 libata-dev (mirror)