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1206cee31c791f7613d461a4770a16d11e40e0bd
[deliverable/linux.git] / security / selinux / hooks.c
1 /*
2 * NSA Security-Enhanced Linux (SELinux) security module
3 *
4 * This file contains the SELinux hook function implementations.
5 *
6 * Authors: Stephen Smalley, <sds@epoch.ncsc.mil>
7 * Chris Vance, <cvance@nai.com>
8 * Wayne Salamon, <wsalamon@nai.com>
9 * James Morris <jmorris@redhat.com>
10 *
11 * Copyright (C) 2001,2002 Networks Associates Technology, Inc.
12 * Copyright (C) 2003-2008 Red Hat, Inc., James Morris <jmorris@redhat.com>
13 * Eric Paris <eparis@redhat.com>
14 * Copyright (C) 2004-2005 Trusted Computer Solutions, Inc.
15 * <dgoeddel@trustedcs.com>
16 * Copyright (C) 2006, 2007, 2009 Hewlett-Packard Development Company, L.P.
17 * Paul Moore <paul@paul-moore.com>
18 * Copyright (C) 2007 Hitachi Software Engineering Co., Ltd.
19 * Yuichi Nakamura <ynakam@hitachisoft.jp>
20 *
21 * This program is free software; you can redistribute it and/or modify
22 * it under the terms of the GNU General Public License version 2,
23 * as published by the Free Software Foundation.
24 */
25
26 #include <linux/init.h>
27 #include <linux/kd.h>
28 #include <linux/kernel.h>
29 #include <linux/tracehook.h>
30 #include <linux/errno.h>
31 #include <linux/ext2_fs.h>
32 #include <linux/sched.h>
33 #include <linux/security.h>
34 #include <linux/xattr.h>
35 #include <linux/capability.h>
36 #include <linux/unistd.h>
37 #include <linux/mm.h>
38 #include <linux/mman.h>
39 #include <linux/slab.h>
40 #include <linux/pagemap.h>
41 #include <linux/proc_fs.h>
42 #include <linux/swap.h>
43 #include <linux/spinlock.h>
44 #include <linux/syscalls.h>
45 #include <linux/dcache.h>
46 #include <linux/file.h>
47 #include <linux/fdtable.h>
48 #include <linux/namei.h>
49 #include <linux/mount.h>
50 #include <linux/netfilter_ipv4.h>
51 #include <linux/netfilter_ipv6.h>
52 #include <linux/tty.h>
53 #include <net/icmp.h>
54 #include <net/ip.h> /* for local_port_range[] */
55 #include <net/tcp.h> /* struct or_callable used in sock_rcv_skb */
56 #include <net/net_namespace.h>
57 #include <net/netlabel.h>
58 #include <linux/uaccess.h>
59 #include <asm/ioctls.h>
60 #include <linux/atomic.h>
61 #include <linux/bitops.h>
62 #include <linux/interrupt.h>
63 #include <linux/netdevice.h> /* for network interface checks */
64 #include <linux/netlink.h>
65 #include <linux/tcp.h>
66 #include <linux/udp.h>
67 #include <linux/dccp.h>
68 #include <linux/quota.h>
69 #include <linux/un.h> /* for Unix socket types */
70 #include <net/af_unix.h> /* for Unix socket types */
71 #include <linux/parser.h>
72 #include <linux/nfs_mount.h>
73 #include <net/ipv6.h>
74 #include <linux/hugetlb.h>
75 #include <linux/personality.h>
76 #include <linux/audit.h>
77 #include <linux/string.h>
78 #include <linux/selinux.h>
79 #include <linux/mutex.h>
80 #include <linux/posix-timers.h>
81 #include <linux/syslog.h>
82 #include <linux/user_namespace.h>
83
84 #include "avc.h"
85 #include "objsec.h"
86 #include "netif.h"
87 #include "netnode.h"
88 #include "netport.h"
89 #include "xfrm.h"
90 #include "netlabel.h"
91 #include "audit.h"
92
93 #define NUM_SEL_MNT_OPTS 5
94
95 extern struct security_operations *security_ops;
96
97 /* SECMARK reference count */
98 static atomic_t selinux_secmark_refcount = ATOMIC_INIT(0);
99
100 #ifdef CONFIG_SECURITY_SELINUX_DEVELOP
101 int selinux_enforcing;
102
103 static int __init enforcing_setup(char *str)
104 {
105 unsigned long enforcing;
106 if (!strict_strtoul(str, 0, &enforcing))
107 selinux_enforcing = enforcing ? 1 : 0;
108 return 1;
109 }
110 __setup("enforcing=", enforcing_setup);
111 #endif
112
113 #ifdef CONFIG_SECURITY_SELINUX_BOOTPARAM
114 int selinux_enabled = CONFIG_SECURITY_SELINUX_BOOTPARAM_VALUE;
115
116 static int __init selinux_enabled_setup(char *str)
117 {
118 unsigned long enabled;
119 if (!strict_strtoul(str, 0, &enabled))
120 selinux_enabled = enabled ? 1 : 0;
121 return 1;
122 }
123 __setup("selinux=", selinux_enabled_setup);
124 #else
125 int selinux_enabled = 1;
126 #endif
127
128 static struct kmem_cache *sel_inode_cache;
129
130 /**
131 * selinux_secmark_enabled - Check to see if SECMARK is currently enabled
132 *
133 * Description:
134 * This function checks the SECMARK reference counter to see if any SECMARK
135 * targets are currently configured, if the reference counter is greater than
136 * zero SECMARK is considered to be enabled. Returns true (1) if SECMARK is
137 * enabled, false (0) if SECMARK is disabled.
138 *
139 */
140 static int selinux_secmark_enabled(void)
141 {
142 return (atomic_read(&selinux_secmark_refcount) > 0);
143 }
144
145 /*
146 * initialise the security for the init task
147 */
148 static void cred_init_security(void)
149 {
150 struct cred *cred = (struct cred *) current->real_cred;
151 struct task_security_struct *tsec;
152
153 tsec = kzalloc(sizeof(struct task_security_struct), GFP_KERNEL);
154 if (!tsec)
155 panic("SELinux: Failed to initialize initial task.\n");
156
157 tsec->osid = tsec->sid = SECINITSID_KERNEL;
158 cred->security = tsec;
159 }
160
161 /*
162 * get the security ID of a set of credentials
163 */
164 static inline u32 cred_sid(const struct cred *cred)
165 {
166 const struct task_security_struct *tsec;
167
168 tsec = cred->security;
169 return tsec->sid;
170 }
171
172 /*
173 * get the objective security ID of a task
174 */
175 static inline u32 task_sid(const struct task_struct *task)
176 {
177 u32 sid;
178
179 rcu_read_lock();
180 sid = cred_sid(__task_cred(task));
181 rcu_read_unlock();
182 return sid;
183 }
184
185 /*
186 * get the subjective security ID of the current task
187 */
188 static inline u32 current_sid(void)
189 {
190 const struct task_security_struct *tsec = current_security();
191
192 return tsec->sid;
193 }
194
195 /* Allocate and free functions for each kind of security blob. */
196
197 static int inode_alloc_security(struct inode *inode)
198 {
199 struct inode_security_struct *isec;
200 u32 sid = current_sid();
201
202 isec = kmem_cache_zalloc(sel_inode_cache, GFP_NOFS);
203 if (!isec)
204 return -ENOMEM;
205
206 mutex_init(&isec->lock);
207 INIT_LIST_HEAD(&isec->list);
208 isec->inode = inode;
209 isec->sid = SECINITSID_UNLABELED;
210 isec->sclass = SECCLASS_FILE;
211 isec->task_sid = sid;
212 inode->i_security = isec;
213
214 return 0;
215 }
216
217 static void inode_free_security(struct inode *inode)
218 {
219 struct inode_security_struct *isec = inode->i_security;
220 struct superblock_security_struct *sbsec = inode->i_sb->s_security;
221
222 spin_lock(&sbsec->isec_lock);
223 if (!list_empty(&isec->list))
224 list_del_init(&isec->list);
225 spin_unlock(&sbsec->isec_lock);
226
227 inode->i_security = NULL;
228 kmem_cache_free(sel_inode_cache, isec);
229 }
230
231 static int file_alloc_security(struct file *file)
232 {
233 struct file_security_struct *fsec;
234 u32 sid = current_sid();
235
236 fsec = kzalloc(sizeof(struct file_security_struct), GFP_KERNEL);
237 if (!fsec)
238 return -ENOMEM;
239
240 fsec->sid = sid;
241 fsec->fown_sid = sid;
242 file->f_security = fsec;
243
244 return 0;
245 }
246
247 static void file_free_security(struct file *file)
248 {
249 struct file_security_struct *fsec = file->f_security;
250 file->f_security = NULL;
251 kfree(fsec);
252 }
253
254 static int superblock_alloc_security(struct super_block *sb)
255 {
256 struct superblock_security_struct *sbsec;
257
258 sbsec = kzalloc(sizeof(struct superblock_security_struct), GFP_KERNEL);
259 if (!sbsec)
260 return -ENOMEM;
261
262 mutex_init(&sbsec->lock);
263 INIT_LIST_HEAD(&sbsec->isec_head);
264 spin_lock_init(&sbsec->isec_lock);
265 sbsec->sb = sb;
266 sbsec->sid = SECINITSID_UNLABELED;
267 sbsec->def_sid = SECINITSID_FILE;
268 sbsec->mntpoint_sid = SECINITSID_UNLABELED;
269 sb->s_security = sbsec;
270
271 return 0;
272 }
273
274 static void superblock_free_security(struct super_block *sb)
275 {
276 struct superblock_security_struct *sbsec = sb->s_security;
277 sb->s_security = NULL;
278 kfree(sbsec);
279 }
280
281 /* The security server must be initialized before
282 any labeling or access decisions can be provided. */
283 extern int ss_initialized;
284
285 /* The file system's label must be initialized prior to use. */
286
287 static const char *labeling_behaviors[6] = {
288 "uses xattr",
289 "uses transition SIDs",
290 "uses task SIDs",
291 "uses genfs_contexts",
292 "not configured for labeling",
293 "uses mountpoint labeling",
294 };
295
296 static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dentry);
297
298 static inline int inode_doinit(struct inode *inode)
299 {
300 return inode_doinit_with_dentry(inode, NULL);
301 }
302
303 enum {
304 Opt_error = -1,
305 Opt_context = 1,
306 Opt_fscontext = 2,
307 Opt_defcontext = 3,
308 Opt_rootcontext = 4,
309 Opt_labelsupport = 5,
310 };
311
312 static const match_table_t tokens = {
313 {Opt_context, CONTEXT_STR "%s"},
314 {Opt_fscontext, FSCONTEXT_STR "%s"},
315 {Opt_defcontext, DEFCONTEXT_STR "%s"},
316 {Opt_rootcontext, ROOTCONTEXT_STR "%s"},
317 {Opt_labelsupport, LABELSUPP_STR},
318 {Opt_error, NULL},
319 };
320
321 #define SEL_MOUNT_FAIL_MSG "SELinux: duplicate or incompatible mount options\n"
322
323 static int may_context_mount_sb_relabel(u32 sid,
324 struct superblock_security_struct *sbsec,
325 const struct cred *cred)
326 {
327 const struct task_security_struct *tsec = cred->security;
328 int rc;
329
330 rc = avc_has_perm(tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM,
331 FILESYSTEM__RELABELFROM, NULL);
332 if (rc)
333 return rc;
334
335 rc = avc_has_perm(tsec->sid, sid, SECCLASS_FILESYSTEM,
336 FILESYSTEM__RELABELTO, NULL);
337 return rc;
338 }
339
340 static int may_context_mount_inode_relabel(u32 sid,
341 struct superblock_security_struct *sbsec,
342 const struct cred *cred)
343 {
344 const struct task_security_struct *tsec = cred->security;
345 int rc;
346 rc = avc_has_perm(tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM,
347 FILESYSTEM__RELABELFROM, NULL);
348 if (rc)
349 return rc;
350
351 rc = avc_has_perm(sid, sbsec->sid, SECCLASS_FILESYSTEM,
352 FILESYSTEM__ASSOCIATE, NULL);
353 return rc;
354 }
355
356 static int sb_finish_set_opts(struct super_block *sb)
357 {
358 struct superblock_security_struct *sbsec = sb->s_security;
359 struct dentry *root = sb->s_root;
360 struct inode *root_inode = root->d_inode;
361 int rc = 0;
362
363 if (sbsec->behavior == SECURITY_FS_USE_XATTR) {
364 /* Make sure that the xattr handler exists and that no
365 error other than -ENODATA is returned by getxattr on
366 the root directory. -ENODATA is ok, as this may be
367 the first boot of the SELinux kernel before we have
368 assigned xattr values to the filesystem. */
369 if (!root_inode->i_op->getxattr) {
370 printk(KERN_WARNING "SELinux: (dev %s, type %s) has no "
371 "xattr support\n", sb->s_id, sb->s_type->name);
372 rc = -EOPNOTSUPP;
373 goto out;
374 }
375 rc = root_inode->i_op->getxattr(root, XATTR_NAME_SELINUX, NULL, 0);
376 if (rc < 0 && rc != -ENODATA) {
377 if (rc == -EOPNOTSUPP)
378 printk(KERN_WARNING "SELinux: (dev %s, type "
379 "%s) has no security xattr handler\n",
380 sb->s_id, sb->s_type->name);
381 else
382 printk(KERN_WARNING "SELinux: (dev %s, type "
383 "%s) getxattr errno %d\n", sb->s_id,
384 sb->s_type->name, -rc);
385 goto out;
386 }
387 }
388
389 sbsec->flags |= (SE_SBINITIALIZED | SE_SBLABELSUPP);
390
391 if (sbsec->behavior > ARRAY_SIZE(labeling_behaviors))
392 printk(KERN_ERR "SELinux: initialized (dev %s, type %s), unknown behavior\n",
393 sb->s_id, sb->s_type->name);
394 else
395 printk(KERN_DEBUG "SELinux: initialized (dev %s, type %s), %s\n",
396 sb->s_id, sb->s_type->name,
397 labeling_behaviors[sbsec->behavior-1]);
398
399 if (sbsec->behavior == SECURITY_FS_USE_GENFS ||
400 sbsec->behavior == SECURITY_FS_USE_MNTPOINT ||
401 sbsec->behavior == SECURITY_FS_USE_NONE ||
402 sbsec->behavior > ARRAY_SIZE(labeling_behaviors))
403 sbsec->flags &= ~SE_SBLABELSUPP;
404
405 /* Special handling for sysfs. Is genfs but also has setxattr handler*/
406 if (strncmp(sb->s_type->name, "sysfs", sizeof("sysfs")) == 0)
407 sbsec->flags |= SE_SBLABELSUPP;
408
409 /* Initialize the root inode. */
410 rc = inode_doinit_with_dentry(root_inode, root);
411
412 /* Initialize any other inodes associated with the superblock, e.g.
413 inodes created prior to initial policy load or inodes created
414 during get_sb by a pseudo filesystem that directly
415 populates itself. */
416 spin_lock(&sbsec->isec_lock);
417 next_inode:
418 if (!list_empty(&sbsec->isec_head)) {
419 struct inode_security_struct *isec =
420 list_entry(sbsec->isec_head.next,
421 struct inode_security_struct, list);
422 struct inode *inode = isec->inode;
423 spin_unlock(&sbsec->isec_lock);
424 inode = igrab(inode);
425 if (inode) {
426 if (!IS_PRIVATE(inode))
427 inode_doinit(inode);
428 iput(inode);
429 }
430 spin_lock(&sbsec->isec_lock);
431 list_del_init(&isec->list);
432 goto next_inode;
433 }
434 spin_unlock(&sbsec->isec_lock);
435 out:
436 return rc;
437 }
438
439 /*
440 * This function should allow an FS to ask what it's mount security
441 * options were so it can use those later for submounts, displaying
442 * mount options, or whatever.
443 */
444 static int selinux_get_mnt_opts(const struct super_block *sb,
445 struct security_mnt_opts *opts)
446 {
447 int rc = 0, i;
448 struct superblock_security_struct *sbsec = sb->s_security;
449 char *context = NULL;
450 u32 len;
451 char tmp;
452
453 security_init_mnt_opts(opts);
454
455 if (!(sbsec->flags & SE_SBINITIALIZED))
456 return -EINVAL;
457
458 if (!ss_initialized)
459 return -EINVAL;
460
461 tmp = sbsec->flags & SE_MNTMASK;
462 /* count the number of mount options for this sb */
463 for (i = 0; i < 8; i++) {
464 if (tmp & 0x01)
465 opts->num_mnt_opts++;
466 tmp >>= 1;
467 }
468 /* Check if the Label support flag is set */
469 if (sbsec->flags & SE_SBLABELSUPP)
470 opts->num_mnt_opts++;
471
472 opts->mnt_opts = kcalloc(opts->num_mnt_opts, sizeof(char *), GFP_ATOMIC);
473 if (!opts->mnt_opts) {
474 rc = -ENOMEM;
475 goto out_free;
476 }
477
478 opts->mnt_opts_flags = kcalloc(opts->num_mnt_opts, sizeof(int), GFP_ATOMIC);
479 if (!opts->mnt_opts_flags) {
480 rc = -ENOMEM;
481 goto out_free;
482 }
483
484 i = 0;
485 if (sbsec->flags & FSCONTEXT_MNT) {
486 rc = security_sid_to_context(sbsec->sid, &context, &len);
487 if (rc)
488 goto out_free;
489 opts->mnt_opts[i] = context;
490 opts->mnt_opts_flags[i++] = FSCONTEXT_MNT;
491 }
492 if (sbsec->flags & CONTEXT_MNT) {
493 rc = security_sid_to_context(sbsec->mntpoint_sid, &context, &len);
494 if (rc)
495 goto out_free;
496 opts->mnt_opts[i] = context;
497 opts->mnt_opts_flags[i++] = CONTEXT_MNT;
498 }
499 if (sbsec->flags & DEFCONTEXT_MNT) {
500 rc = security_sid_to_context(sbsec->def_sid, &context, &len);
501 if (rc)
502 goto out_free;
503 opts->mnt_opts[i] = context;
504 opts->mnt_opts_flags[i++] = DEFCONTEXT_MNT;
505 }
506 if (sbsec->flags & ROOTCONTEXT_MNT) {
507 struct inode *root = sbsec->sb->s_root->d_inode;
508 struct inode_security_struct *isec = root->i_security;
509
510 rc = security_sid_to_context(isec->sid, &context, &len);
511 if (rc)
512 goto out_free;
513 opts->mnt_opts[i] = context;
514 opts->mnt_opts_flags[i++] = ROOTCONTEXT_MNT;
515 }
516 if (sbsec->flags & SE_SBLABELSUPP) {
517 opts->mnt_opts[i] = NULL;
518 opts->mnt_opts_flags[i++] = SE_SBLABELSUPP;
519 }
520
521 BUG_ON(i != opts->num_mnt_opts);
522
523 return 0;
524
525 out_free:
526 security_free_mnt_opts(opts);
527 return rc;
528 }
529
530 static int bad_option(struct superblock_security_struct *sbsec, char flag,
531 u32 old_sid, u32 new_sid)
532 {
533 char mnt_flags = sbsec->flags & SE_MNTMASK;
534
535 /* check if the old mount command had the same options */
536 if (sbsec->flags & SE_SBINITIALIZED)
537 if (!(sbsec->flags & flag) ||
538 (old_sid != new_sid))
539 return 1;
540
541 /* check if we were passed the same options twice,
542 * aka someone passed context=a,context=b
543 */
544 if (!(sbsec->flags & SE_SBINITIALIZED))
545 if (mnt_flags & flag)
546 return 1;
547 return 0;
548 }
549
550 /*
551 * Allow filesystems with binary mount data to explicitly set mount point
552 * labeling information.
553 */
554 static int selinux_set_mnt_opts(struct super_block *sb,
555 struct security_mnt_opts *opts)
556 {
557 const struct cred *cred = current_cred();
558 int rc = 0, i;
559 struct superblock_security_struct *sbsec = sb->s_security;
560 const char *name = sb->s_type->name;
561 struct inode *inode = sbsec->sb->s_root->d_inode;
562 struct inode_security_struct *root_isec = inode->i_security;
563 u32 fscontext_sid = 0, context_sid = 0, rootcontext_sid = 0;
564 u32 defcontext_sid = 0;
565 char **mount_options = opts->mnt_opts;
566 int *flags = opts->mnt_opts_flags;
567 int num_opts = opts->num_mnt_opts;
568
569 mutex_lock(&sbsec->lock);
570
571 if (!ss_initialized) {
572 if (!num_opts) {
573 /* Defer initialization until selinux_complete_init,
574 after the initial policy is loaded and the security
575 server is ready to handle calls. */
576 goto out;
577 }
578 rc = -EINVAL;
579 printk(KERN_WARNING "SELinux: Unable to set superblock options "
580 "before the security server is initialized\n");
581 goto out;
582 }
583
584 /*
585 * Binary mount data FS will come through this function twice. Once
586 * from an explicit call and once from the generic calls from the vfs.
587 * Since the generic VFS calls will not contain any security mount data
588 * we need to skip the double mount verification.
589 *
590 * This does open a hole in which we will not notice if the first
591 * mount using this sb set explict options and a second mount using
592 * this sb does not set any security options. (The first options
593 * will be used for both mounts)
594 */
595 if ((sbsec->flags & SE_SBINITIALIZED) && (sb->s_type->fs_flags & FS_BINARY_MOUNTDATA)
596 && (num_opts == 0))
597 goto out;
598
599 /*
600 * parse the mount options, check if they are valid sids.
601 * also check if someone is trying to mount the same sb more
602 * than once with different security options.
603 */
604 for (i = 0; i < num_opts; i++) {
605 u32 sid;
606
607 if (flags[i] == SE_SBLABELSUPP)
608 continue;
609 rc = security_context_to_sid(mount_options[i],
610 strlen(mount_options[i]), &sid);
611 if (rc) {
612 printk(KERN_WARNING "SELinux: security_context_to_sid"
613 "(%s) failed for (dev %s, type %s) errno=%d\n",
614 mount_options[i], sb->s_id, name, rc);
615 goto out;
616 }
617 switch (flags[i]) {
618 case FSCONTEXT_MNT:
619 fscontext_sid = sid;
620
621 if (bad_option(sbsec, FSCONTEXT_MNT, sbsec->sid,
622 fscontext_sid))
623 goto out_double_mount;
624
625 sbsec->flags |= FSCONTEXT_MNT;
626 break;
627 case CONTEXT_MNT:
628 context_sid = sid;
629
630 if (bad_option(sbsec, CONTEXT_MNT, sbsec->mntpoint_sid,
631 context_sid))
632 goto out_double_mount;
633
634 sbsec->flags |= CONTEXT_MNT;
635 break;
636 case ROOTCONTEXT_MNT:
637 rootcontext_sid = sid;
638
639 if (bad_option(sbsec, ROOTCONTEXT_MNT, root_isec->sid,
640 rootcontext_sid))
641 goto out_double_mount;
642
643 sbsec->flags |= ROOTCONTEXT_MNT;
644
645 break;
646 case DEFCONTEXT_MNT:
647 defcontext_sid = sid;
648
649 if (bad_option(sbsec, DEFCONTEXT_MNT, sbsec->def_sid,
650 defcontext_sid))
651 goto out_double_mount;
652
653 sbsec->flags |= DEFCONTEXT_MNT;
654
655 break;
656 default:
657 rc = -EINVAL;
658 goto out;
659 }
660 }
661
662 if (sbsec->flags & SE_SBINITIALIZED) {
663 /* previously mounted with options, but not on this attempt? */
664 if ((sbsec->flags & SE_MNTMASK) && !num_opts)
665 goto out_double_mount;
666 rc = 0;
667 goto out;
668 }
669
670 if (strcmp(sb->s_type->name, "proc") == 0)
671 sbsec->flags |= SE_SBPROC;
672
673 /* Determine the labeling behavior to use for this filesystem type. */
674 rc = security_fs_use((sbsec->flags & SE_SBPROC) ? "proc" : sb->s_type->name, &sbsec->behavior, &sbsec->sid);
675 if (rc) {
676 printk(KERN_WARNING "%s: security_fs_use(%s) returned %d\n",
677 __func__, sb->s_type->name, rc);
678 goto out;
679 }
680
681 /* sets the context of the superblock for the fs being mounted. */
682 if (fscontext_sid) {
683 rc = may_context_mount_sb_relabel(fscontext_sid, sbsec, cred);
684 if (rc)
685 goto out;
686
687 sbsec->sid = fscontext_sid;
688 }
689
690 /*
691 * Switch to using mount point labeling behavior.
692 * sets the label used on all file below the mountpoint, and will set
693 * the superblock context if not already set.
694 */
695 if (context_sid) {
696 if (!fscontext_sid) {
697 rc = may_context_mount_sb_relabel(context_sid, sbsec,
698 cred);
699 if (rc)
700 goto out;
701 sbsec->sid = context_sid;
702 } else {
703 rc = may_context_mount_inode_relabel(context_sid, sbsec,
704 cred);
705 if (rc)
706 goto out;
707 }
708 if (!rootcontext_sid)
709 rootcontext_sid = context_sid;
710
711 sbsec->mntpoint_sid = context_sid;
712 sbsec->behavior = SECURITY_FS_USE_MNTPOINT;
713 }
714
715 if (rootcontext_sid) {
716 rc = may_context_mount_inode_relabel(rootcontext_sid, sbsec,
717 cred);
718 if (rc)
719 goto out;
720
721 root_isec->sid = rootcontext_sid;
722 root_isec->initialized = 1;
723 }
724
725 if (defcontext_sid) {
726 if (sbsec->behavior != SECURITY_FS_USE_XATTR) {
727 rc = -EINVAL;
728 printk(KERN_WARNING "SELinux: defcontext option is "
729 "invalid for this filesystem type\n");
730 goto out;
731 }
732
733 if (defcontext_sid != sbsec->def_sid) {
734 rc = may_context_mount_inode_relabel(defcontext_sid,
735 sbsec, cred);
736 if (rc)
737 goto out;
738 }
739
740 sbsec->def_sid = defcontext_sid;
741 }
742
743 rc = sb_finish_set_opts(sb);
744 out:
745 mutex_unlock(&sbsec->lock);
746 return rc;
747 out_double_mount:
748 rc = -EINVAL;
749 printk(KERN_WARNING "SELinux: mount invalid. Same superblock, different "
750 "security settings for (dev %s, type %s)\n", sb->s_id, name);
751 goto out;
752 }
753
754 static void selinux_sb_clone_mnt_opts(const struct super_block *oldsb,
755 struct super_block *newsb)
756 {
757 const struct superblock_security_struct *oldsbsec = oldsb->s_security;
758 struct superblock_security_struct *newsbsec = newsb->s_security;
759
760 int set_fscontext = (oldsbsec->flags & FSCONTEXT_MNT);
761 int set_context = (oldsbsec->flags & CONTEXT_MNT);
762 int set_rootcontext = (oldsbsec->flags & ROOTCONTEXT_MNT);
763
764 /*
765 * if the parent was able to be mounted it clearly had no special lsm
766 * mount options. thus we can safely deal with this superblock later
767 */
768 if (!ss_initialized)
769 return;
770
771 /* how can we clone if the old one wasn't set up?? */
772 BUG_ON(!(oldsbsec->flags & SE_SBINITIALIZED));
773
774 /* if fs is reusing a sb, just let its options stand... */
775 if (newsbsec->flags & SE_SBINITIALIZED)
776 return;
777
778 mutex_lock(&newsbsec->lock);
779
780 newsbsec->flags = oldsbsec->flags;
781
782 newsbsec->sid = oldsbsec->sid;
783 newsbsec->def_sid = oldsbsec->def_sid;
784 newsbsec->behavior = oldsbsec->behavior;
785
786 if (set_context) {
787 u32 sid = oldsbsec->mntpoint_sid;
788
789 if (!set_fscontext)
790 newsbsec->sid = sid;
791 if (!set_rootcontext) {
792 struct inode *newinode = newsb->s_root->d_inode;
793 struct inode_security_struct *newisec = newinode->i_security;
794 newisec->sid = sid;
795 }
796 newsbsec->mntpoint_sid = sid;
797 }
798 if (set_rootcontext) {
799 const struct inode *oldinode = oldsb->s_root->d_inode;
800 const struct inode_security_struct *oldisec = oldinode->i_security;
801 struct inode *newinode = newsb->s_root->d_inode;
802 struct inode_security_struct *newisec = newinode->i_security;
803
804 newisec->sid = oldisec->sid;
805 }
806
807 sb_finish_set_opts(newsb);
808 mutex_unlock(&newsbsec->lock);
809 }
810
811 static int selinux_parse_opts_str(char *options,
812 struct security_mnt_opts *opts)
813 {
814 char *p;
815 char *context = NULL, *defcontext = NULL;
816 char *fscontext = NULL, *rootcontext = NULL;
817 int rc, num_mnt_opts = 0;
818
819 opts->num_mnt_opts = 0;
820
821 /* Standard string-based options. */
822 while ((p = strsep(&options, "|")) != NULL) {
823 int token;
824 substring_t args[MAX_OPT_ARGS];
825
826 if (!*p)
827 continue;
828
829 token = match_token(p, tokens, args);
830
831 switch (token) {
832 case Opt_context:
833 if (context || defcontext) {
834 rc = -EINVAL;
835 printk(KERN_WARNING SEL_MOUNT_FAIL_MSG);
836 goto out_err;
837 }
838 context = match_strdup(&args[0]);
839 if (!context) {
840 rc = -ENOMEM;
841 goto out_err;
842 }
843 break;
844
845 case Opt_fscontext:
846 if (fscontext) {
847 rc = -EINVAL;
848 printk(KERN_WARNING SEL_MOUNT_FAIL_MSG);
849 goto out_err;
850 }
851 fscontext = match_strdup(&args[0]);
852 if (!fscontext) {
853 rc = -ENOMEM;
854 goto out_err;
855 }
856 break;
857
858 case Opt_rootcontext:
859 if (rootcontext) {
860 rc = -EINVAL;
861 printk(KERN_WARNING SEL_MOUNT_FAIL_MSG);
862 goto out_err;
863 }
864 rootcontext = match_strdup(&args[0]);
865 if (!rootcontext) {
866 rc = -ENOMEM;
867 goto out_err;
868 }
869 break;
870
871 case Opt_defcontext:
872 if (context || defcontext) {
873 rc = -EINVAL;
874 printk(KERN_WARNING SEL_MOUNT_FAIL_MSG);
875 goto out_err;
876 }
877 defcontext = match_strdup(&args[0]);
878 if (!defcontext) {
879 rc = -ENOMEM;
880 goto out_err;
881 }
882 break;
883 case Opt_labelsupport:
884 break;
885 default:
886 rc = -EINVAL;
887 printk(KERN_WARNING "SELinux: unknown mount option\n");
888 goto out_err;
889
890 }
891 }
892
893 rc = -ENOMEM;
894 opts->mnt_opts = kcalloc(NUM_SEL_MNT_OPTS, sizeof(char *), GFP_ATOMIC);
895 if (!opts->mnt_opts)
896 goto out_err;
897
898 opts->mnt_opts_flags = kcalloc(NUM_SEL_MNT_OPTS, sizeof(int), GFP_ATOMIC);
899 if (!opts->mnt_opts_flags) {
900 kfree(opts->mnt_opts);
901 goto out_err;
902 }
903
904 if (fscontext) {
905 opts->mnt_opts[num_mnt_opts] = fscontext;
906 opts->mnt_opts_flags[num_mnt_opts++] = FSCONTEXT_MNT;
907 }
908 if (context) {
909 opts->mnt_opts[num_mnt_opts] = context;
910 opts->mnt_opts_flags[num_mnt_opts++] = CONTEXT_MNT;
911 }
912 if (rootcontext) {
913 opts->mnt_opts[num_mnt_opts] = rootcontext;
914 opts->mnt_opts_flags[num_mnt_opts++] = ROOTCONTEXT_MNT;
915 }
916 if (defcontext) {
917 opts->mnt_opts[num_mnt_opts] = defcontext;
918 opts->mnt_opts_flags[num_mnt_opts++] = DEFCONTEXT_MNT;
919 }
920
921 opts->num_mnt_opts = num_mnt_opts;
922 return 0;
923
924 out_err:
925 kfree(context);
926 kfree(defcontext);
927 kfree(fscontext);
928 kfree(rootcontext);
929 return rc;
930 }
931 /*
932 * string mount options parsing and call set the sbsec
933 */
934 static int superblock_doinit(struct super_block *sb, void *data)
935 {
936 int rc = 0;
937 char *options = data;
938 struct security_mnt_opts opts;
939
940 security_init_mnt_opts(&opts);
941
942 if (!data)
943 goto out;
944
945 BUG_ON(sb->s_type->fs_flags & FS_BINARY_MOUNTDATA);
946
947 rc = selinux_parse_opts_str(options, &opts);
948 if (rc)
949 goto out_err;
950
951 out:
952 rc = selinux_set_mnt_opts(sb, &opts);
953
954 out_err:
955 security_free_mnt_opts(&opts);
956 return rc;
957 }
958
959 static void selinux_write_opts(struct seq_file *m,
960 struct security_mnt_opts *opts)
961 {
962 int i;
963 char *prefix;
964
965 for (i = 0; i < opts->num_mnt_opts; i++) {
966 char *has_comma;
967
968 if (opts->mnt_opts[i])
969 has_comma = strchr(opts->mnt_opts[i], ',');
970 else
971 has_comma = NULL;
972
973 switch (opts->mnt_opts_flags[i]) {
974 case CONTEXT_MNT:
975 prefix = CONTEXT_STR;
976 break;
977 case FSCONTEXT_MNT:
978 prefix = FSCONTEXT_STR;
979 break;
980 case ROOTCONTEXT_MNT:
981 prefix = ROOTCONTEXT_STR;
982 break;
983 case DEFCONTEXT_MNT:
984 prefix = DEFCONTEXT_STR;
985 break;
986 case SE_SBLABELSUPP:
987 seq_putc(m, ',');
988 seq_puts(m, LABELSUPP_STR);
989 continue;
990 default:
991 BUG();
992 return;
993 };
994 /* we need a comma before each option */
995 seq_putc(m, ',');
996 seq_puts(m, prefix);
997 if (has_comma)
998 seq_putc(m, '\"');
999 seq_puts(m, opts->mnt_opts[i]);
1000 if (has_comma)
1001 seq_putc(m, '\"');
1002 }
1003 }
1004
1005 static int selinux_sb_show_options(struct seq_file *m, struct super_block *sb)
1006 {
1007 struct security_mnt_opts opts;
1008 int rc;
1009
1010 rc = selinux_get_mnt_opts(sb, &opts);
1011 if (rc) {
1012 /* before policy load we may get EINVAL, don't show anything */
1013 if (rc == -EINVAL)
1014 rc = 0;
1015 return rc;
1016 }
1017
1018 selinux_write_opts(m, &opts);
1019
1020 security_free_mnt_opts(&opts);
1021
1022 return rc;
1023 }
1024
1025 static inline u16 inode_mode_to_security_class(umode_t mode)
1026 {
1027 switch (mode & S_IFMT) {
1028 case S_IFSOCK:
1029 return SECCLASS_SOCK_FILE;
1030 case S_IFLNK:
1031 return SECCLASS_LNK_FILE;
1032 case S_IFREG:
1033 return SECCLASS_FILE;
1034 case S_IFBLK:
1035 return SECCLASS_BLK_FILE;
1036 case S_IFDIR:
1037 return SECCLASS_DIR;
1038 case S_IFCHR:
1039 return SECCLASS_CHR_FILE;
1040 case S_IFIFO:
1041 return SECCLASS_FIFO_FILE;
1042
1043 }
1044
1045 return SECCLASS_FILE;
1046 }
1047
1048 static inline int default_protocol_stream(int protocol)
1049 {
1050 return (protocol == IPPROTO_IP || protocol == IPPROTO_TCP);
1051 }
1052
1053 static inline int default_protocol_dgram(int protocol)
1054 {
1055 return (protocol == IPPROTO_IP || protocol == IPPROTO_UDP);
1056 }
1057
1058 static inline u16 socket_type_to_security_class(int family, int type, int protocol)
1059 {
1060 switch (family) {
1061 case PF_UNIX:
1062 switch (type) {
1063 case SOCK_STREAM:
1064 case SOCK_SEQPACKET:
1065 return SECCLASS_UNIX_STREAM_SOCKET;
1066 case SOCK_DGRAM:
1067 return SECCLASS_UNIX_DGRAM_SOCKET;
1068 }
1069 break;
1070 case PF_INET:
1071 case PF_INET6:
1072 switch (type) {
1073 case SOCK_STREAM:
1074 if (default_protocol_stream(protocol))
1075 return SECCLASS_TCP_SOCKET;
1076 else
1077 return SECCLASS_RAWIP_SOCKET;
1078 case SOCK_DGRAM:
1079 if (default_protocol_dgram(protocol))
1080 return SECCLASS_UDP_SOCKET;
1081 else
1082 return SECCLASS_RAWIP_SOCKET;
1083 case SOCK_DCCP:
1084 return SECCLASS_DCCP_SOCKET;
1085 default:
1086 return SECCLASS_RAWIP_SOCKET;
1087 }
1088 break;
1089 case PF_NETLINK:
1090 switch (protocol) {
1091 case NETLINK_ROUTE:
1092 return SECCLASS_NETLINK_ROUTE_SOCKET;
1093 case NETLINK_FIREWALL:
1094 return SECCLASS_NETLINK_FIREWALL_SOCKET;
1095 case NETLINK_INET_DIAG:
1096 return SECCLASS_NETLINK_TCPDIAG_SOCKET;
1097 case NETLINK_NFLOG:
1098 return SECCLASS_NETLINK_NFLOG_SOCKET;
1099 case NETLINK_XFRM:
1100 return SECCLASS_NETLINK_XFRM_SOCKET;
1101 case NETLINK_SELINUX:
1102 return SECCLASS_NETLINK_SELINUX_SOCKET;
1103 case NETLINK_AUDIT:
1104 return SECCLASS_NETLINK_AUDIT_SOCKET;
1105 case NETLINK_IP6_FW:
1106 return SECCLASS_NETLINK_IP6FW_SOCKET;
1107 case NETLINK_DNRTMSG:
1108 return SECCLASS_NETLINK_DNRT_SOCKET;
1109 case NETLINK_KOBJECT_UEVENT:
1110 return SECCLASS_NETLINK_KOBJECT_UEVENT_SOCKET;
1111 default:
1112 return SECCLASS_NETLINK_SOCKET;
1113 }
1114 case PF_PACKET:
1115 return SECCLASS_PACKET_SOCKET;
1116 case PF_KEY:
1117 return SECCLASS_KEY_SOCKET;
1118 case PF_APPLETALK:
1119 return SECCLASS_APPLETALK_SOCKET;
1120 }
1121
1122 return SECCLASS_SOCKET;
1123 }
1124
1125 #ifdef CONFIG_PROC_FS
1126 static int selinux_proc_get_sid(struct dentry *dentry,
1127 u16 tclass,
1128 u32 *sid)
1129 {
1130 int rc;
1131 char *buffer, *path;
1132
1133 buffer = (char *)__get_free_page(GFP_KERNEL);
1134 if (!buffer)
1135 return -ENOMEM;
1136
1137 path = dentry_path_raw(dentry, buffer, PAGE_SIZE);
1138 if (IS_ERR(path))
1139 rc = PTR_ERR(path);
1140 else {
1141 /* each process gets a /proc/PID/ entry. Strip off the
1142 * PID part to get a valid selinux labeling.
1143 * e.g. /proc/1/net/rpc/nfs -> /net/rpc/nfs */
1144 while (path[1] >= '0' && path[1] <= '9') {
1145 path[1] = '/';
1146 path++;
1147 }
1148 rc = security_genfs_sid("proc", path, tclass, sid);
1149 }
1150 free_page((unsigned long)buffer);
1151 return rc;
1152 }
1153 #else
1154 static int selinux_proc_get_sid(struct dentry *dentry,
1155 u16 tclass,
1156 u32 *sid)
1157 {
1158 return -EINVAL;
1159 }
1160 #endif
1161
1162 /* The inode's security attributes must be initialized before first use. */
1163 static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dentry)
1164 {
1165 struct superblock_security_struct *sbsec = NULL;
1166 struct inode_security_struct *isec = inode->i_security;
1167 u32 sid;
1168 struct dentry *dentry;
1169 #define INITCONTEXTLEN 255
1170 char *context = NULL;
1171 unsigned len = 0;
1172 int rc = 0;
1173
1174 if (isec->initialized)
1175 goto out;
1176
1177 mutex_lock(&isec->lock);
1178 if (isec->initialized)
1179 goto out_unlock;
1180
1181 sbsec = inode->i_sb->s_security;
1182 if (!(sbsec->flags & SE_SBINITIALIZED)) {
1183 /* Defer initialization until selinux_complete_init,
1184 after the initial policy is loaded and the security
1185 server is ready to handle calls. */
1186 spin_lock(&sbsec->isec_lock);
1187 if (list_empty(&isec->list))
1188 list_add(&isec->list, &sbsec->isec_head);
1189 spin_unlock(&sbsec->isec_lock);
1190 goto out_unlock;
1191 }
1192
1193 switch (sbsec->behavior) {
1194 case SECURITY_FS_USE_XATTR:
1195 if (!inode->i_op->getxattr) {
1196 isec->sid = sbsec->def_sid;
1197 break;
1198 }
1199
1200 /* Need a dentry, since the xattr API requires one.
1201 Life would be simpler if we could just pass the inode. */
1202 if (opt_dentry) {
1203 /* Called from d_instantiate or d_splice_alias. */
1204 dentry = dget(opt_dentry);
1205 } else {
1206 /* Called from selinux_complete_init, try to find a dentry. */
1207 dentry = d_find_alias(inode);
1208 }
1209 if (!dentry) {
1210 /*
1211 * this is can be hit on boot when a file is accessed
1212 * before the policy is loaded. When we load policy we
1213 * may find inodes that have no dentry on the
1214 * sbsec->isec_head list. No reason to complain as these
1215 * will get fixed up the next time we go through
1216 * inode_doinit with a dentry, before these inodes could
1217 * be used again by userspace.
1218 */
1219 goto out_unlock;
1220 }
1221
1222 len = INITCONTEXTLEN;
1223 context = kmalloc(len+1, GFP_NOFS);
1224 if (!context) {
1225 rc = -ENOMEM;
1226 dput(dentry);
1227 goto out_unlock;
1228 }
1229 context[len] = '\0';
1230 rc = inode->i_op->getxattr(dentry, XATTR_NAME_SELINUX,
1231 context, len);
1232 if (rc == -ERANGE) {
1233 kfree(context);
1234
1235 /* Need a larger buffer. Query for the right size. */
1236 rc = inode->i_op->getxattr(dentry, XATTR_NAME_SELINUX,
1237 NULL, 0);
1238 if (rc < 0) {
1239 dput(dentry);
1240 goto out_unlock;
1241 }
1242 len = rc;
1243 context = kmalloc(len+1, GFP_NOFS);
1244 if (!context) {
1245 rc = -ENOMEM;
1246 dput(dentry);
1247 goto out_unlock;
1248 }
1249 context[len] = '\0';
1250 rc = inode->i_op->getxattr(dentry,
1251 XATTR_NAME_SELINUX,
1252 context, len);
1253 }
1254 dput(dentry);
1255 if (rc < 0) {
1256 if (rc != -ENODATA) {
1257 printk(KERN_WARNING "SELinux: %s: getxattr returned "
1258 "%d for dev=%s ino=%ld\n", __func__,
1259 -rc, inode->i_sb->s_id, inode->i_ino);
1260 kfree(context);
1261 goto out_unlock;
1262 }
1263 /* Map ENODATA to the default file SID */
1264 sid = sbsec->def_sid;
1265 rc = 0;
1266 } else {
1267 rc = security_context_to_sid_default(context, rc, &sid,
1268 sbsec->def_sid,
1269 GFP_NOFS);
1270 if (rc) {
1271 char *dev = inode->i_sb->s_id;
1272 unsigned long ino = inode->i_ino;
1273
1274 if (rc == -EINVAL) {
1275 if (printk_ratelimit())
1276 printk(KERN_NOTICE "SELinux: inode=%lu on dev=%s was found to have an invalid "
1277 "context=%s. This indicates you may need to relabel the inode or the "
1278 "filesystem in question.\n", ino, dev, context);
1279 } else {
1280 printk(KERN_WARNING "SELinux: %s: context_to_sid(%s) "
1281 "returned %d for dev=%s ino=%ld\n",
1282 __func__, context, -rc, dev, ino);
1283 }
1284 kfree(context);
1285 /* Leave with the unlabeled SID */
1286 rc = 0;
1287 break;
1288 }
1289 }
1290 kfree(context);
1291 isec->sid = sid;
1292 break;
1293 case SECURITY_FS_USE_TASK:
1294 isec->sid = isec->task_sid;
1295 break;
1296 case SECURITY_FS_USE_TRANS:
1297 /* Default to the fs SID. */
1298 isec->sid = sbsec->sid;
1299
1300 /* Try to obtain a transition SID. */
1301 isec->sclass = inode_mode_to_security_class(inode->i_mode);
1302 rc = security_transition_sid(isec->task_sid, sbsec->sid,
1303 isec->sclass, NULL, &sid);
1304 if (rc)
1305 goto out_unlock;
1306 isec->sid = sid;
1307 break;
1308 case SECURITY_FS_USE_MNTPOINT:
1309 isec->sid = sbsec->mntpoint_sid;
1310 break;
1311 default:
1312 /* Default to the fs superblock SID. */
1313 isec->sid = sbsec->sid;
1314
1315 if ((sbsec->flags & SE_SBPROC) && !S_ISLNK(inode->i_mode)) {
1316 if (opt_dentry) {
1317 isec->sclass = inode_mode_to_security_class(inode->i_mode);
1318 rc = selinux_proc_get_sid(opt_dentry,
1319 isec->sclass,
1320 &sid);
1321 if (rc)
1322 goto out_unlock;
1323 isec->sid = sid;
1324 }
1325 }
1326 break;
1327 }
1328
1329 isec->initialized = 1;
1330
1331 out_unlock:
1332 mutex_unlock(&isec->lock);
1333 out:
1334 if (isec->sclass == SECCLASS_FILE)
1335 isec->sclass = inode_mode_to_security_class(inode->i_mode);
1336 return rc;
1337 }
1338
1339 /* Convert a Linux signal to an access vector. */
1340 static inline u32 signal_to_av(int sig)
1341 {
1342 u32 perm = 0;
1343
1344 switch (sig) {
1345 case SIGCHLD:
1346 /* Commonly granted from child to parent. */
1347 perm = PROCESS__SIGCHLD;
1348 break;
1349 case SIGKILL:
1350 /* Cannot be caught or ignored */
1351 perm = PROCESS__SIGKILL;
1352 break;
1353 case SIGSTOP:
1354 /* Cannot be caught or ignored */
1355 perm = PROCESS__SIGSTOP;
1356 break;
1357 default:
1358 /* All other signals. */
1359 perm = PROCESS__SIGNAL;
1360 break;
1361 }
1362
1363 return perm;
1364 }
1365
1366 /*
1367 * Check permission between a pair of credentials
1368 * fork check, ptrace check, etc.
1369 */
1370 static int cred_has_perm(const struct cred *actor,
1371 const struct cred *target,
1372 u32 perms)
1373 {
1374 u32 asid = cred_sid(actor), tsid = cred_sid(target);
1375
1376 return avc_has_perm(asid, tsid, SECCLASS_PROCESS, perms, NULL);
1377 }
1378
1379 /*
1380 * Check permission between a pair of tasks, e.g. signal checks,
1381 * fork check, ptrace check, etc.
1382 * tsk1 is the actor and tsk2 is the target
1383 * - this uses the default subjective creds of tsk1
1384 */
1385 static int task_has_perm(const struct task_struct *tsk1,
1386 const struct task_struct *tsk2,
1387 u32 perms)
1388 {
1389 const struct task_security_struct *__tsec1, *__tsec2;
1390 u32 sid1, sid2;
1391
1392 rcu_read_lock();
1393 __tsec1 = __task_cred(tsk1)->security; sid1 = __tsec1->sid;
1394 __tsec2 = __task_cred(tsk2)->security; sid2 = __tsec2->sid;
1395 rcu_read_unlock();
1396 return avc_has_perm(sid1, sid2, SECCLASS_PROCESS, perms, NULL);
1397 }
1398
1399 /*
1400 * Check permission between current and another task, e.g. signal checks,
1401 * fork check, ptrace check, etc.
1402 * current is the actor and tsk2 is the target
1403 * - this uses current's subjective creds
1404 */
1405 static int current_has_perm(const struct task_struct *tsk,
1406 u32 perms)
1407 {
1408 u32 sid, tsid;
1409
1410 sid = current_sid();
1411 tsid = task_sid(tsk);
1412 return avc_has_perm(sid, tsid, SECCLASS_PROCESS, perms, NULL);
1413 }
1414
1415 #if CAP_LAST_CAP > 63
1416 #error Fix SELinux to handle capabilities > 63.
1417 #endif
1418
1419 /* Check whether a task is allowed to use a capability. */
1420 static int task_has_capability(struct task_struct *tsk,
1421 const struct cred *cred,
1422 int cap, int audit)
1423 {
1424 struct common_audit_data ad;
1425 struct av_decision avd;
1426 u16 sclass;
1427 u32 sid = cred_sid(cred);
1428 u32 av = CAP_TO_MASK(cap);
1429 int rc;
1430
1431 COMMON_AUDIT_DATA_INIT(&ad, CAP);
1432 ad.tsk = tsk;
1433 ad.u.cap = cap;
1434
1435 switch (CAP_TO_INDEX(cap)) {
1436 case 0:
1437 sclass = SECCLASS_CAPABILITY;
1438 break;
1439 case 1:
1440 sclass = SECCLASS_CAPABILITY2;
1441 break;
1442 default:
1443 printk(KERN_ERR
1444 "SELinux: out of range capability %d\n", cap);
1445 BUG();
1446 return -EINVAL;
1447 }
1448
1449 rc = avc_has_perm_noaudit(sid, sid, sclass, av, 0, &avd);
1450 if (audit == SECURITY_CAP_AUDIT) {
1451 int rc2 = avc_audit(sid, sid, sclass, av, &avd, rc, &ad, 0);
1452 if (rc2)
1453 return rc2;
1454 }
1455 return rc;
1456 }
1457
1458 /* Check whether a task is allowed to use a system operation. */
1459 static int task_has_system(struct task_struct *tsk,
1460 u32 perms)
1461 {
1462 u32 sid = task_sid(tsk);
1463
1464 return avc_has_perm(sid, SECINITSID_KERNEL,
1465 SECCLASS_SYSTEM, perms, NULL);
1466 }
1467
1468 /* Check whether a task has a particular permission to an inode.
1469 The 'adp' parameter is optional and allows other audit
1470 data to be passed (e.g. the dentry). */
1471 static int inode_has_perm(const struct cred *cred,
1472 struct inode *inode,
1473 u32 perms,
1474 struct common_audit_data *adp,
1475 unsigned flags)
1476 {
1477 struct inode_security_struct *isec;
1478 u32 sid;
1479
1480 validate_creds(cred);
1481
1482 if (unlikely(IS_PRIVATE(inode)))
1483 return 0;
1484
1485 sid = cred_sid(cred);
1486 isec = inode->i_security;
1487
1488 return avc_has_perm_flags(sid, isec->sid, isec->sclass, perms, adp, flags);
1489 }
1490
1491 static int inode_has_perm_noadp(const struct cred *cred,
1492 struct inode *inode,
1493 u32 perms,
1494 unsigned flags)
1495 {
1496 struct common_audit_data ad;
1497
1498 COMMON_AUDIT_DATA_INIT(&ad, INODE);
1499 ad.u.inode = inode;
1500 return inode_has_perm(cred, inode, perms, &ad, flags);
1501 }
1502
1503 /* Same as inode_has_perm, but pass explicit audit data containing
1504 the dentry to help the auditing code to more easily generate the
1505 pathname if needed. */
1506 static inline int dentry_has_perm(const struct cred *cred,
1507 struct dentry *dentry,
1508 u32 av)
1509 {
1510 struct inode *inode = dentry->d_inode;
1511 struct common_audit_data ad;
1512
1513 COMMON_AUDIT_DATA_INIT(&ad, DENTRY);
1514 ad.u.dentry = dentry;
1515 return inode_has_perm(cred, inode, av, &ad, 0);
1516 }
1517
1518 /* Same as inode_has_perm, but pass explicit audit data containing
1519 the path to help the auditing code to more easily generate the
1520 pathname if needed. */
1521 static inline int path_has_perm(const struct cred *cred,
1522 struct path *path,
1523 u32 av)
1524 {
1525 struct inode *inode = path->dentry->d_inode;
1526 struct common_audit_data ad;
1527
1528 COMMON_AUDIT_DATA_INIT(&ad, PATH);
1529 ad.u.path = *path;
1530 return inode_has_perm(cred, inode, av, &ad, 0);
1531 }
1532
1533 /* Check whether a task can use an open file descriptor to
1534 access an inode in a given way. Check access to the
1535 descriptor itself, and then use dentry_has_perm to
1536 check a particular permission to the file.
1537 Access to the descriptor is implicitly granted if it
1538 has the same SID as the process. If av is zero, then
1539 access to the file is not checked, e.g. for cases
1540 where only the descriptor is affected like seek. */
1541 static int file_has_perm(const struct cred *cred,
1542 struct file *file,
1543 u32 av)
1544 {
1545 struct file_security_struct *fsec = file->f_security;
1546 struct inode *inode = file->f_path.dentry->d_inode;
1547 struct common_audit_data ad;
1548 u32 sid = cred_sid(cred);
1549 int rc;
1550
1551 COMMON_AUDIT_DATA_INIT(&ad, PATH);
1552 ad.u.path = file->f_path;
1553
1554 if (sid != fsec->sid) {
1555 rc = avc_has_perm(sid, fsec->sid,
1556 SECCLASS_FD,
1557 FD__USE,
1558 &ad);
1559 if (rc)
1560 goto out;
1561 }
1562
1563 /* av is zero if only checking access to the descriptor. */
1564 rc = 0;
1565 if (av)
1566 rc = inode_has_perm(cred, inode, av, &ad, 0);
1567
1568 out:
1569 return rc;
1570 }
1571
1572 /* Check whether a task can create a file. */
1573 static int may_create(struct inode *dir,
1574 struct dentry *dentry,
1575 u16 tclass)
1576 {
1577 const struct task_security_struct *tsec = current_security();
1578 struct inode_security_struct *dsec;
1579 struct superblock_security_struct *sbsec;
1580 u32 sid, newsid;
1581 struct common_audit_data ad;
1582 int rc;
1583
1584 dsec = dir->i_security;
1585 sbsec = dir->i_sb->s_security;
1586
1587 sid = tsec->sid;
1588 newsid = tsec->create_sid;
1589
1590 COMMON_AUDIT_DATA_INIT(&ad, DENTRY);
1591 ad.u.dentry = dentry;
1592
1593 rc = avc_has_perm(sid, dsec->sid, SECCLASS_DIR,
1594 DIR__ADD_NAME | DIR__SEARCH,
1595 &ad);
1596 if (rc)
1597 return rc;
1598
1599 if (!newsid || !(sbsec->flags & SE_SBLABELSUPP)) {
1600 rc = security_transition_sid(sid, dsec->sid, tclass,
1601 &dentry->d_name, &newsid);
1602 if (rc)
1603 return rc;
1604 }
1605
1606 rc = avc_has_perm(sid, newsid, tclass, FILE__CREATE, &ad);
1607 if (rc)
1608 return rc;
1609
1610 return avc_has_perm(newsid, sbsec->sid,
1611 SECCLASS_FILESYSTEM,
1612 FILESYSTEM__ASSOCIATE, &ad);
1613 }
1614
1615 /* Check whether a task can create a key. */
1616 static int may_create_key(u32 ksid,
1617 struct task_struct *ctx)
1618 {
1619 u32 sid = task_sid(ctx);
1620
1621 return avc_has_perm(sid, ksid, SECCLASS_KEY, KEY__CREATE, NULL);
1622 }
1623
1624 #define MAY_LINK 0
1625 #define MAY_UNLINK 1
1626 #define MAY_RMDIR 2
1627
1628 /* Check whether a task can link, unlink, or rmdir a file/directory. */
1629 static int may_link(struct inode *dir,
1630 struct dentry *dentry,
1631 int kind)
1632
1633 {
1634 struct inode_security_struct *dsec, *isec;
1635 struct common_audit_data ad;
1636 u32 sid = current_sid();
1637 u32 av;
1638 int rc;
1639
1640 dsec = dir->i_security;
1641 isec = dentry->d_inode->i_security;
1642
1643 COMMON_AUDIT_DATA_INIT(&ad, DENTRY);
1644 ad.u.dentry = dentry;
1645
1646 av = DIR__SEARCH;
1647 av |= (kind ? DIR__REMOVE_NAME : DIR__ADD_NAME);
1648 rc = avc_has_perm(sid, dsec->sid, SECCLASS_DIR, av, &ad);
1649 if (rc)
1650 return rc;
1651
1652 switch (kind) {
1653 case MAY_LINK:
1654 av = FILE__LINK;
1655 break;
1656 case MAY_UNLINK:
1657 av = FILE__UNLINK;
1658 break;
1659 case MAY_RMDIR:
1660 av = DIR__RMDIR;
1661 break;
1662 default:
1663 printk(KERN_WARNING "SELinux: %s: unrecognized kind %d\n",
1664 __func__, kind);
1665 return 0;
1666 }
1667
1668 rc = avc_has_perm(sid, isec->sid, isec->sclass, av, &ad);
1669 return rc;
1670 }
1671
1672 static inline int may_rename(struct inode *old_dir,
1673 struct dentry *old_dentry,
1674 struct inode *new_dir,
1675 struct dentry *new_dentry)
1676 {
1677 struct inode_security_struct *old_dsec, *new_dsec, *old_isec, *new_isec;
1678 struct common_audit_data ad;
1679 u32 sid = current_sid();
1680 u32 av;
1681 int old_is_dir, new_is_dir;
1682 int rc;
1683
1684 old_dsec = old_dir->i_security;
1685 old_isec = old_dentry->d_inode->i_security;
1686 old_is_dir = S_ISDIR(old_dentry->d_inode->i_mode);
1687 new_dsec = new_dir->i_security;
1688
1689 COMMON_AUDIT_DATA_INIT(&ad, DENTRY);
1690
1691 ad.u.dentry = old_dentry;
1692 rc = avc_has_perm(sid, old_dsec->sid, SECCLASS_DIR,
1693 DIR__REMOVE_NAME | DIR__SEARCH, &ad);
1694 if (rc)
1695 return rc;
1696 rc = avc_has_perm(sid, old_isec->sid,
1697 old_isec->sclass, FILE__RENAME, &ad);
1698 if (rc)
1699 return rc;
1700 if (old_is_dir && new_dir != old_dir) {
1701 rc = avc_has_perm(sid, old_isec->sid,
1702 old_isec->sclass, DIR__REPARENT, &ad);
1703 if (rc)
1704 return rc;
1705 }
1706
1707 ad.u.dentry = new_dentry;
1708 av = DIR__ADD_NAME | DIR__SEARCH;
1709 if (new_dentry->d_inode)
1710 av |= DIR__REMOVE_NAME;
1711 rc = avc_has_perm(sid, new_dsec->sid, SECCLASS_DIR, av, &ad);
1712 if (rc)
1713 return rc;
1714 if (new_dentry->d_inode) {
1715 new_isec = new_dentry->d_inode->i_security;
1716 new_is_dir = S_ISDIR(new_dentry->d_inode->i_mode);
1717 rc = avc_has_perm(sid, new_isec->sid,
1718 new_isec->sclass,
1719 (new_is_dir ? DIR__RMDIR : FILE__UNLINK), &ad);
1720 if (rc)
1721 return rc;
1722 }
1723
1724 return 0;
1725 }
1726
1727 /* Check whether a task can perform a filesystem operation. */
1728 static int superblock_has_perm(const struct cred *cred,
1729 struct super_block *sb,
1730 u32 perms,
1731 struct common_audit_data *ad)
1732 {
1733 struct superblock_security_struct *sbsec;
1734 u32 sid = cred_sid(cred);
1735
1736 sbsec = sb->s_security;
1737 return avc_has_perm(sid, sbsec->sid, SECCLASS_FILESYSTEM, perms, ad);
1738 }
1739
1740 /* Convert a Linux mode and permission mask to an access vector. */
1741 static inline u32 file_mask_to_av(int mode, int mask)
1742 {
1743 u32 av = 0;
1744
1745 if ((mode & S_IFMT) != S_IFDIR) {
1746 if (mask & MAY_EXEC)
1747 av |= FILE__EXECUTE;
1748 if (mask & MAY_READ)
1749 av |= FILE__READ;
1750
1751 if (mask & MAY_APPEND)
1752 av |= FILE__APPEND;
1753 else if (mask & MAY_WRITE)
1754 av |= FILE__WRITE;
1755
1756 } else {
1757 if (mask & MAY_EXEC)
1758 av |= DIR__SEARCH;
1759 if (mask & MAY_WRITE)
1760 av |= DIR__WRITE;
1761 if (mask & MAY_READ)
1762 av |= DIR__READ;
1763 }
1764
1765 return av;
1766 }
1767
1768 /* Convert a Linux file to an access vector. */
1769 static inline u32 file_to_av(struct file *file)
1770 {
1771 u32 av = 0;
1772
1773 if (file->f_mode & FMODE_READ)
1774 av |= FILE__READ;
1775 if (file->f_mode & FMODE_WRITE) {
1776 if (file->f_flags & O_APPEND)
1777 av |= FILE__APPEND;
1778 else
1779 av |= FILE__WRITE;
1780 }
1781 if (!av) {
1782 /*
1783 * Special file opened with flags 3 for ioctl-only use.
1784 */
1785 av = FILE__IOCTL;
1786 }
1787
1788 return av;
1789 }
1790
1791 /*
1792 * Convert a file to an access vector and include the correct open
1793 * open permission.
1794 */
1795 static inline u32 open_file_to_av(struct file *file)
1796 {
1797 u32 av = file_to_av(file);
1798
1799 if (selinux_policycap_openperm)
1800 av |= FILE__OPEN;
1801
1802 return av;
1803 }
1804
1805 /* Hook functions begin here. */
1806
1807 static int selinux_ptrace_access_check(struct task_struct *child,
1808 unsigned int mode)
1809 {
1810 int rc;
1811
1812 rc = cap_ptrace_access_check(child, mode);
1813 if (rc)
1814 return rc;
1815
1816 if (mode == PTRACE_MODE_READ) {
1817 u32 sid = current_sid();
1818 u32 csid = task_sid(child);
1819 return avc_has_perm(sid, csid, SECCLASS_FILE, FILE__READ, NULL);
1820 }
1821
1822 return current_has_perm(child, PROCESS__PTRACE);
1823 }
1824
1825 static int selinux_ptrace_traceme(struct task_struct *parent)
1826 {
1827 int rc;
1828
1829 rc = cap_ptrace_traceme(parent);
1830 if (rc)
1831 return rc;
1832
1833 return task_has_perm(parent, current, PROCESS__PTRACE);
1834 }
1835
1836 static int selinux_capget(struct task_struct *target, kernel_cap_t *effective,
1837 kernel_cap_t *inheritable, kernel_cap_t *permitted)
1838 {
1839 int error;
1840
1841 error = current_has_perm(target, PROCESS__GETCAP);
1842 if (error)
1843 return error;
1844
1845 return cap_capget(target, effective, inheritable, permitted);
1846 }
1847
1848 static int selinux_capset(struct cred *new, const struct cred *old,
1849 const kernel_cap_t *effective,
1850 const kernel_cap_t *inheritable,
1851 const kernel_cap_t *permitted)
1852 {
1853 int error;
1854
1855 error = cap_capset(new, old,
1856 effective, inheritable, permitted);
1857 if (error)
1858 return error;
1859
1860 return cred_has_perm(old, new, PROCESS__SETCAP);
1861 }
1862
1863 /*
1864 * (This comment used to live with the selinux_task_setuid hook,
1865 * which was removed).
1866 *
1867 * Since setuid only affects the current process, and since the SELinux
1868 * controls are not based on the Linux identity attributes, SELinux does not
1869 * need to control this operation. However, SELinux does control the use of
1870 * the CAP_SETUID and CAP_SETGID capabilities using the capable hook.
1871 */
1872
1873 static int selinux_capable(struct task_struct *tsk, const struct cred *cred,
1874 struct user_namespace *ns, int cap, int audit)
1875 {
1876 int rc;
1877
1878 rc = cap_capable(tsk, cred, ns, cap, audit);
1879 if (rc)
1880 return rc;
1881
1882 return task_has_capability(tsk, cred, cap, audit);
1883 }
1884
1885 static int selinux_quotactl(int cmds, int type, int id, struct super_block *sb)
1886 {
1887 const struct cred *cred = current_cred();
1888 int rc = 0;
1889
1890 if (!sb)
1891 return 0;
1892
1893 switch (cmds) {
1894 case Q_SYNC:
1895 case Q_QUOTAON:
1896 case Q_QUOTAOFF:
1897 case Q_SETINFO:
1898 case Q_SETQUOTA:
1899 rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAMOD, NULL);
1900 break;
1901 case Q_GETFMT:
1902 case Q_GETINFO:
1903 case Q_GETQUOTA:
1904 rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAGET, NULL);
1905 break;
1906 default:
1907 rc = 0; /* let the kernel handle invalid cmds */
1908 break;
1909 }
1910 return rc;
1911 }
1912
1913 static int selinux_quota_on(struct dentry *dentry)
1914 {
1915 const struct cred *cred = current_cred();
1916
1917 return dentry_has_perm(cred, dentry, FILE__QUOTAON);
1918 }
1919
1920 static int selinux_syslog(int type)
1921 {
1922 int rc;
1923
1924 switch (type) {
1925 case SYSLOG_ACTION_READ_ALL: /* Read last kernel messages */
1926 case SYSLOG_ACTION_SIZE_BUFFER: /* Return size of the log buffer */
1927 rc = task_has_system(current, SYSTEM__SYSLOG_READ);
1928 break;
1929 case SYSLOG_ACTION_CONSOLE_OFF: /* Disable logging to console */
1930 case SYSLOG_ACTION_CONSOLE_ON: /* Enable logging to console */
1931 /* Set level of messages printed to console */
1932 case SYSLOG_ACTION_CONSOLE_LEVEL:
1933 rc = task_has_system(current, SYSTEM__SYSLOG_CONSOLE);
1934 break;
1935 case SYSLOG_ACTION_CLOSE: /* Close log */
1936 case SYSLOG_ACTION_OPEN: /* Open log */
1937 case SYSLOG_ACTION_READ: /* Read from log */
1938 case SYSLOG_ACTION_READ_CLEAR: /* Read/clear last kernel messages */
1939 case SYSLOG_ACTION_CLEAR: /* Clear ring buffer */
1940 default:
1941 rc = task_has_system(current, SYSTEM__SYSLOG_MOD);
1942 break;
1943 }
1944 return rc;
1945 }
1946
1947 /*
1948 * Check that a process has enough memory to allocate a new virtual
1949 * mapping. 0 means there is enough memory for the allocation to
1950 * succeed and -ENOMEM implies there is not.
1951 *
1952 * Do not audit the selinux permission check, as this is applied to all
1953 * processes that allocate mappings.
1954 */
1955 static int selinux_vm_enough_memory(struct mm_struct *mm, long pages)
1956 {
1957 int rc, cap_sys_admin = 0;
1958
1959 rc = selinux_capable(current, current_cred(),
1960 &init_user_ns, CAP_SYS_ADMIN,
1961 SECURITY_CAP_NOAUDIT);
1962 if (rc == 0)
1963 cap_sys_admin = 1;
1964
1965 return __vm_enough_memory(mm, pages, cap_sys_admin);
1966 }
1967
1968 /* binprm security operations */
1969
1970 static int selinux_bprm_set_creds(struct linux_binprm *bprm)
1971 {
1972 const struct task_security_struct *old_tsec;
1973 struct task_security_struct *new_tsec;
1974 struct inode_security_struct *isec;
1975 struct common_audit_data ad;
1976 struct inode *inode = bprm->file->f_path.dentry->d_inode;
1977 int rc;
1978
1979 rc = cap_bprm_set_creds(bprm);
1980 if (rc)
1981 return rc;
1982
1983 /* SELinux context only depends on initial program or script and not
1984 * the script interpreter */
1985 if (bprm->cred_prepared)
1986 return 0;
1987
1988 old_tsec = current_security();
1989 new_tsec = bprm->cred->security;
1990 isec = inode->i_security;
1991
1992 /* Default to the current task SID. */
1993 new_tsec->sid = old_tsec->sid;
1994 new_tsec->osid = old_tsec->sid;
1995
1996 /* Reset fs, key, and sock SIDs on execve. */
1997 new_tsec->create_sid = 0;
1998 new_tsec->keycreate_sid = 0;
1999 new_tsec->sockcreate_sid = 0;
2000
2001 if (old_tsec->exec_sid) {
2002 new_tsec->sid = old_tsec->exec_sid;
2003 /* Reset exec SID on execve. */
2004 new_tsec->exec_sid = 0;
2005 } else {
2006 /* Check for a default transition on this program. */
2007 rc = security_transition_sid(old_tsec->sid, isec->sid,
2008 SECCLASS_PROCESS, NULL,
2009 &new_tsec->sid);
2010 if (rc)
2011 return rc;
2012 }
2013
2014 COMMON_AUDIT_DATA_INIT(&ad, PATH);
2015 ad.u.path = bprm->file->f_path;
2016
2017 if (bprm->file->f_path.mnt->mnt_flags & MNT_NOSUID)
2018 new_tsec->sid = old_tsec->sid;
2019
2020 if (new_tsec->sid == old_tsec->sid) {
2021 rc = avc_has_perm(old_tsec->sid, isec->sid,
2022 SECCLASS_FILE, FILE__EXECUTE_NO_TRANS, &ad);
2023 if (rc)
2024 return rc;
2025 } else {
2026 /* Check permissions for the transition. */
2027 rc = avc_has_perm(old_tsec->sid, new_tsec->sid,
2028 SECCLASS_PROCESS, PROCESS__TRANSITION, &ad);
2029 if (rc)
2030 return rc;
2031
2032 rc = avc_has_perm(new_tsec->sid, isec->sid,
2033 SECCLASS_FILE, FILE__ENTRYPOINT, &ad);
2034 if (rc)
2035 return rc;
2036
2037 /* Check for shared state */
2038 if (bprm->unsafe & LSM_UNSAFE_SHARE) {
2039 rc = avc_has_perm(old_tsec->sid, new_tsec->sid,
2040 SECCLASS_PROCESS, PROCESS__SHARE,
2041 NULL);
2042 if (rc)
2043 return -EPERM;
2044 }
2045
2046 /* Make sure that anyone attempting to ptrace over a task that
2047 * changes its SID has the appropriate permit */
2048 if (bprm->unsafe &
2049 (LSM_UNSAFE_PTRACE | LSM_UNSAFE_PTRACE_CAP)) {
2050 struct task_struct *tracer;
2051 struct task_security_struct *sec;
2052 u32 ptsid = 0;
2053
2054 rcu_read_lock();
2055 tracer = ptrace_parent(current);
2056 if (likely(tracer != NULL)) {
2057 sec = __task_cred(tracer)->security;
2058 ptsid = sec->sid;
2059 }
2060 rcu_read_unlock();
2061
2062 if (ptsid != 0) {
2063 rc = avc_has_perm(ptsid, new_tsec->sid,
2064 SECCLASS_PROCESS,
2065 PROCESS__PTRACE, NULL);
2066 if (rc)
2067 return -EPERM;
2068 }
2069 }
2070
2071 /* Clear any possibly unsafe personality bits on exec: */
2072 bprm->per_clear |= PER_CLEAR_ON_SETID;
2073 }
2074
2075 return 0;
2076 }
2077
2078 static int selinux_bprm_secureexec(struct linux_binprm *bprm)
2079 {
2080 const struct task_security_struct *tsec = current_security();
2081 u32 sid, osid;
2082 int atsecure = 0;
2083
2084 sid = tsec->sid;
2085 osid = tsec->osid;
2086
2087 if (osid != sid) {
2088 /* Enable secure mode for SIDs transitions unless
2089 the noatsecure permission is granted between
2090 the two SIDs, i.e. ahp returns 0. */
2091 atsecure = avc_has_perm(osid, sid,
2092 SECCLASS_PROCESS,
2093 PROCESS__NOATSECURE, NULL);
2094 }
2095
2096 return (atsecure || cap_bprm_secureexec(bprm));
2097 }
2098
2099 /* Derived from fs/exec.c:flush_old_files. */
2100 static inline void flush_unauthorized_files(const struct cred *cred,
2101 struct files_struct *files)
2102 {
2103 struct common_audit_data ad;
2104 struct file *file, *devnull = NULL;
2105 struct tty_struct *tty;
2106 struct fdtable *fdt;
2107 long j = -1;
2108 int drop_tty = 0;
2109
2110 tty = get_current_tty();
2111 if (tty) {
2112 spin_lock(&tty_files_lock);
2113 if (!list_empty(&tty->tty_files)) {
2114 struct tty_file_private *file_priv;
2115 struct inode *inode;
2116
2117 /* Revalidate access to controlling tty.
2118 Use inode_has_perm on the tty inode directly rather
2119 than using file_has_perm, as this particular open
2120 file may belong to another process and we are only
2121 interested in the inode-based check here. */
2122 file_priv = list_first_entry(&tty->tty_files,
2123 struct tty_file_private, list);
2124 file = file_priv->file;
2125 inode = file->f_path.dentry->d_inode;
2126 if (inode_has_perm_noadp(cred, inode,
2127 FILE__READ | FILE__WRITE, 0)) {
2128 drop_tty = 1;
2129 }
2130 }
2131 spin_unlock(&tty_files_lock);
2132 tty_kref_put(tty);
2133 }
2134 /* Reset controlling tty. */
2135 if (drop_tty)
2136 no_tty();
2137
2138 /* Revalidate access to inherited open files. */
2139
2140 COMMON_AUDIT_DATA_INIT(&ad, INODE);
2141
2142 spin_lock(&files->file_lock);
2143 for (;;) {
2144 unsigned long set, i;
2145 int fd;
2146
2147 j++;
2148 i = j * __NFDBITS;
2149 fdt = files_fdtable(files);
2150 if (i >= fdt->max_fds)
2151 break;
2152 set = fdt->open_fds->fds_bits[j];
2153 if (!set)
2154 continue;
2155 spin_unlock(&files->file_lock);
2156 for ( ; set ; i++, set >>= 1) {
2157 if (set & 1) {
2158 file = fget(i);
2159 if (!file)
2160 continue;
2161 if (file_has_perm(cred,
2162 file,
2163 file_to_av(file))) {
2164 sys_close(i);
2165 fd = get_unused_fd();
2166 if (fd != i) {
2167 if (fd >= 0)
2168 put_unused_fd(fd);
2169 fput(file);
2170 continue;
2171 }
2172 if (devnull) {
2173 get_file(devnull);
2174 } else {
2175 devnull = dentry_open(
2176 dget(selinux_null),
2177 mntget(selinuxfs_mount),
2178 O_RDWR, cred);
2179 if (IS_ERR(devnull)) {
2180 devnull = NULL;
2181 put_unused_fd(fd);
2182 fput(file);
2183 continue;
2184 }
2185 }
2186 fd_install(fd, devnull);
2187 }
2188 fput(file);
2189 }
2190 }
2191 spin_lock(&files->file_lock);
2192
2193 }
2194 spin_unlock(&files->file_lock);
2195 }
2196
2197 /*
2198 * Prepare a process for imminent new credential changes due to exec
2199 */
2200 static void selinux_bprm_committing_creds(struct linux_binprm *bprm)
2201 {
2202 struct task_security_struct *new_tsec;
2203 struct rlimit *rlim, *initrlim;
2204 int rc, i;
2205
2206 new_tsec = bprm->cred->security;
2207 if (new_tsec->sid == new_tsec->osid)
2208 return;
2209
2210 /* Close files for which the new task SID is not authorized. */
2211 flush_unauthorized_files(bprm->cred, current->files);
2212
2213 /* Always clear parent death signal on SID transitions. */
2214 current->pdeath_signal = 0;
2215
2216 /* Check whether the new SID can inherit resource limits from the old
2217 * SID. If not, reset all soft limits to the lower of the current
2218 * task's hard limit and the init task's soft limit.
2219 *
2220 * Note that the setting of hard limits (even to lower them) can be
2221 * controlled by the setrlimit check. The inclusion of the init task's
2222 * soft limit into the computation is to avoid resetting soft limits
2223 * higher than the default soft limit for cases where the default is
2224 * lower than the hard limit, e.g. RLIMIT_CORE or RLIMIT_STACK.
2225 */
2226 rc = avc_has_perm(new_tsec->osid, new_tsec->sid, SECCLASS_PROCESS,
2227 PROCESS__RLIMITINH, NULL);
2228 if (rc) {
2229 /* protect against do_prlimit() */
2230 task_lock(current);
2231 for (i = 0; i < RLIM_NLIMITS; i++) {
2232 rlim = current->signal->rlim + i;
2233 initrlim = init_task.signal->rlim + i;
2234 rlim->rlim_cur = min(rlim->rlim_max, initrlim->rlim_cur);
2235 }
2236 task_unlock(current);
2237 update_rlimit_cpu(current, rlimit(RLIMIT_CPU));
2238 }
2239 }
2240
2241 /*
2242 * Clean up the process immediately after the installation of new credentials
2243 * due to exec
2244 */
2245 static void selinux_bprm_committed_creds(struct linux_binprm *bprm)
2246 {
2247 const struct task_security_struct *tsec = current_security();
2248 struct itimerval itimer;
2249 u32 osid, sid;
2250 int rc, i;
2251
2252 osid = tsec->osid;
2253 sid = tsec->sid;
2254
2255 if (sid == osid)
2256 return;
2257
2258 /* Check whether the new SID can inherit signal state from the old SID.
2259 * If not, clear itimers to avoid subsequent signal generation and
2260 * flush and unblock signals.
2261 *
2262 * This must occur _after_ the task SID has been updated so that any
2263 * kill done after the flush will be checked against the new SID.
2264 */
2265 rc = avc_has_perm(osid, sid, SECCLASS_PROCESS, PROCESS__SIGINH, NULL);
2266 if (rc) {
2267 memset(&itimer, 0, sizeof itimer);
2268 for (i = 0; i < 3; i++)
2269 do_setitimer(i, &itimer, NULL);
2270 spin_lock_irq(&current->sighand->siglock);
2271 if (!(current->signal->flags & SIGNAL_GROUP_EXIT)) {
2272 __flush_signals(current);
2273 flush_signal_handlers(current, 1);
2274 sigemptyset(&current->blocked);
2275 }
2276 spin_unlock_irq(&current->sighand->siglock);
2277 }
2278
2279 /* Wake up the parent if it is waiting so that it can recheck
2280 * wait permission to the new task SID. */
2281 read_lock(&tasklist_lock);
2282 __wake_up_parent(current, current->real_parent);
2283 read_unlock(&tasklist_lock);
2284 }
2285
2286 /* superblock security operations */
2287
2288 static int selinux_sb_alloc_security(struct super_block *sb)
2289 {
2290 return superblock_alloc_security(sb);
2291 }
2292
2293 static void selinux_sb_free_security(struct super_block *sb)
2294 {
2295 superblock_free_security(sb);
2296 }
2297
2298 static inline int match_prefix(char *prefix, int plen, char *option, int olen)
2299 {
2300 if (plen > olen)
2301 return 0;
2302
2303 return !memcmp(prefix, option, plen);
2304 }
2305
2306 static inline int selinux_option(char *option, int len)
2307 {
2308 return (match_prefix(CONTEXT_STR, sizeof(CONTEXT_STR)-1, option, len) ||
2309 match_prefix(FSCONTEXT_STR, sizeof(FSCONTEXT_STR)-1, option, len) ||
2310 match_prefix(DEFCONTEXT_STR, sizeof(DEFCONTEXT_STR)-1, option, len) ||
2311 match_prefix(ROOTCONTEXT_STR, sizeof(ROOTCONTEXT_STR)-1, option, len) ||
2312 match_prefix(LABELSUPP_STR, sizeof(LABELSUPP_STR)-1, option, len));
2313 }
2314
2315 static inline void take_option(char **to, char *from, int *first, int len)
2316 {
2317 if (!*first) {
2318 **to = ',';
2319 *to += 1;
2320 } else
2321 *first = 0;
2322 memcpy(*to, from, len);
2323 *to += len;
2324 }
2325
2326 static inline void take_selinux_option(char **to, char *from, int *first,
2327 int len)
2328 {
2329 int current_size = 0;
2330
2331 if (!*first) {
2332 **to = '|';
2333 *to += 1;
2334 } else
2335 *first = 0;
2336
2337 while (current_size < len) {
2338 if (*from != '"') {
2339 **to = *from;
2340 *to += 1;
2341 }
2342 from += 1;
2343 current_size += 1;
2344 }
2345 }
2346
2347 static int selinux_sb_copy_data(char *orig, char *copy)
2348 {
2349 int fnosec, fsec, rc = 0;
2350 char *in_save, *in_curr, *in_end;
2351 char *sec_curr, *nosec_save, *nosec;
2352 int open_quote = 0;
2353
2354 in_curr = orig;
2355 sec_curr = copy;
2356
2357 nosec = (char *)get_zeroed_page(GFP_KERNEL);
2358 if (!nosec) {
2359 rc = -ENOMEM;
2360 goto out;
2361 }
2362
2363 nosec_save = nosec;
2364 fnosec = fsec = 1;
2365 in_save = in_end = orig;
2366
2367 do {
2368 if (*in_end == '"')
2369 open_quote = !open_quote;
2370 if ((*in_end == ',' && open_quote == 0) ||
2371 *in_end == '\0') {
2372 int len = in_end - in_curr;
2373
2374 if (selinux_option(in_curr, len))
2375 take_selinux_option(&sec_curr, in_curr, &fsec, len);
2376 else
2377 take_option(&nosec, in_curr, &fnosec, len);
2378
2379 in_curr = in_end + 1;
2380 }
2381 } while (*in_end++);
2382
2383 strcpy(in_save, nosec_save);
2384 free_page((unsigned long)nosec_save);
2385 out:
2386 return rc;
2387 }
2388
2389 static int selinux_sb_remount(struct super_block *sb, void *data)
2390 {
2391 int rc, i, *flags;
2392 struct security_mnt_opts opts;
2393 char *secdata, **mount_options;
2394 struct superblock_security_struct *sbsec = sb->s_security;
2395
2396 if (!(sbsec->flags & SE_SBINITIALIZED))
2397 return 0;
2398
2399 if (!data)
2400 return 0;
2401
2402 if (sb->s_type->fs_flags & FS_BINARY_MOUNTDATA)
2403 return 0;
2404
2405 security_init_mnt_opts(&opts);
2406 secdata = alloc_secdata();
2407 if (!secdata)
2408 return -ENOMEM;
2409 rc = selinux_sb_copy_data(data, secdata);
2410 if (rc)
2411 goto out_free_secdata;
2412
2413 rc = selinux_parse_opts_str(secdata, &opts);
2414 if (rc)
2415 goto out_free_secdata;
2416
2417 mount_options = opts.mnt_opts;
2418 flags = opts.mnt_opts_flags;
2419
2420 for (i = 0; i < opts.num_mnt_opts; i++) {
2421 u32 sid;
2422 size_t len;
2423
2424 if (flags[i] == SE_SBLABELSUPP)
2425 continue;
2426 len = strlen(mount_options[i]);
2427 rc = security_context_to_sid(mount_options[i], len, &sid);
2428 if (rc) {
2429 printk(KERN_WARNING "SELinux: security_context_to_sid"
2430 "(%s) failed for (dev %s, type %s) errno=%d\n",
2431 mount_options[i], sb->s_id, sb->s_type->name, rc);
2432 goto out_free_opts;
2433 }
2434 rc = -EINVAL;
2435 switch (flags[i]) {
2436 case FSCONTEXT_MNT:
2437 if (bad_option(sbsec, FSCONTEXT_MNT, sbsec->sid, sid))
2438 goto out_bad_option;
2439 break;
2440 case CONTEXT_MNT:
2441 if (bad_option(sbsec, CONTEXT_MNT, sbsec->mntpoint_sid, sid))
2442 goto out_bad_option;
2443 break;
2444 case ROOTCONTEXT_MNT: {
2445 struct inode_security_struct *root_isec;
2446 root_isec = sb->s_root->d_inode->i_security;
2447
2448 if (bad_option(sbsec, ROOTCONTEXT_MNT, root_isec->sid, sid))
2449 goto out_bad_option;
2450 break;
2451 }
2452 case DEFCONTEXT_MNT:
2453 if (bad_option(sbsec, DEFCONTEXT_MNT, sbsec->def_sid, sid))
2454 goto out_bad_option;
2455 break;
2456 default:
2457 goto out_free_opts;
2458 }
2459 }
2460
2461 rc = 0;
2462 out_free_opts:
2463 security_free_mnt_opts(&opts);
2464 out_free_secdata:
2465 free_secdata(secdata);
2466 return rc;
2467 out_bad_option:
2468 printk(KERN_WARNING "SELinux: unable to change security options "
2469 "during remount (dev %s, type=%s)\n", sb->s_id,
2470 sb->s_type->name);
2471 goto out_free_opts;
2472 }
2473
2474 static int selinux_sb_kern_mount(struct super_block *sb, int flags, void *data)
2475 {
2476 const struct cred *cred = current_cred();
2477 struct common_audit_data ad;
2478 int rc;
2479
2480 rc = superblock_doinit(sb, data);
2481 if (rc)
2482 return rc;
2483
2484 /* Allow all mounts performed by the kernel */
2485 if (flags & MS_KERNMOUNT)
2486 return 0;
2487
2488 COMMON_AUDIT_DATA_INIT(&ad, DENTRY);
2489 ad.u.dentry = sb->s_root;
2490 return superblock_has_perm(cred, sb, FILESYSTEM__MOUNT, &ad);
2491 }
2492
2493 static int selinux_sb_statfs(struct dentry *dentry)
2494 {
2495 const struct cred *cred = current_cred();
2496 struct common_audit_data ad;
2497
2498 COMMON_AUDIT_DATA_INIT(&ad, DENTRY);
2499 ad.u.dentry = dentry->d_sb->s_root;
2500 return superblock_has_perm(cred, dentry->d_sb, FILESYSTEM__GETATTR, &ad);
2501 }
2502
2503 static int selinux_mount(char *dev_name,
2504 struct path *path,
2505 char *type,
2506 unsigned long flags,
2507 void *data)
2508 {
2509 const struct cred *cred = current_cred();
2510
2511 if (flags & MS_REMOUNT)
2512 return superblock_has_perm(cred, path->mnt->mnt_sb,
2513 FILESYSTEM__REMOUNT, NULL);
2514 else
2515 return path_has_perm(cred, path, FILE__MOUNTON);
2516 }
2517
2518 static int selinux_umount(struct vfsmount *mnt, int flags)
2519 {
2520 const struct cred *cred = current_cred();
2521
2522 return superblock_has_perm(cred, mnt->mnt_sb,
2523 FILESYSTEM__UNMOUNT, NULL);
2524 }
2525
2526 /* inode security operations */
2527
2528 static int selinux_inode_alloc_security(struct inode *inode)
2529 {
2530 return inode_alloc_security(inode);
2531 }
2532
2533 static void selinux_inode_free_security(struct inode *inode)
2534 {
2535 inode_free_security(inode);
2536 }
2537
2538 static int selinux_inode_init_security(struct inode *inode, struct inode *dir,
2539 const struct qstr *qstr, char **name,
2540 void **value, size_t *len)
2541 {
2542 const struct task_security_struct *tsec = current_security();
2543 struct inode_security_struct *dsec;
2544 struct superblock_security_struct *sbsec;
2545 u32 sid, newsid, clen;
2546 int rc;
2547 char *namep = NULL, *context;
2548
2549 dsec = dir->i_security;
2550 sbsec = dir->i_sb->s_security;
2551
2552 sid = tsec->sid;
2553 newsid = tsec->create_sid;
2554
2555 if ((sbsec->flags & SE_SBINITIALIZED) &&
2556 (sbsec->behavior == SECURITY_FS_USE_MNTPOINT))
2557 newsid = sbsec->mntpoint_sid;
2558 else if (!newsid || !(sbsec->flags & SE_SBLABELSUPP)) {
2559 rc = security_transition_sid(sid, dsec->sid,
2560 inode_mode_to_security_class(inode->i_mode),
2561 qstr, &newsid);
2562 if (rc) {
2563 printk(KERN_WARNING "%s: "
2564 "security_transition_sid failed, rc=%d (dev=%s "
2565 "ino=%ld)\n",
2566 __func__,
2567 -rc, inode->i_sb->s_id, inode->i_ino);
2568 return rc;
2569 }
2570 }
2571
2572 /* Possibly defer initialization to selinux_complete_init. */
2573 if (sbsec->flags & SE_SBINITIALIZED) {
2574 struct inode_security_struct *isec = inode->i_security;
2575 isec->sclass = inode_mode_to_security_class(inode->i_mode);
2576 isec->sid = newsid;
2577 isec->initialized = 1;
2578 }
2579
2580 if (!ss_initialized || !(sbsec->flags & SE_SBLABELSUPP))
2581 return -EOPNOTSUPP;
2582
2583 if (name) {
2584 namep = kstrdup(XATTR_SELINUX_SUFFIX, GFP_NOFS);
2585 if (!namep)
2586 return -ENOMEM;
2587 *name = namep;
2588 }
2589
2590 if (value && len) {
2591 rc = security_sid_to_context_force(newsid, &context, &clen);
2592 if (rc) {
2593 kfree(namep);
2594 return rc;
2595 }
2596 *value = context;
2597 *len = clen;
2598 }
2599
2600 return 0;
2601 }
2602
2603 static int selinux_inode_create(struct inode *dir, struct dentry *dentry, int mask)
2604 {
2605 return may_create(dir, dentry, SECCLASS_FILE);
2606 }
2607
2608 static int selinux_inode_link(struct dentry *old_dentry, struct inode *dir, struct dentry *new_dentry)
2609 {
2610 return may_link(dir, old_dentry, MAY_LINK);
2611 }
2612
2613 static int selinux_inode_unlink(struct inode *dir, struct dentry *dentry)
2614 {
2615 return may_link(dir, dentry, MAY_UNLINK);
2616 }
2617
2618 static int selinux_inode_symlink(struct inode *dir, struct dentry *dentry, const char *name)
2619 {
2620 return may_create(dir, dentry, SECCLASS_LNK_FILE);
2621 }
2622
2623 static int selinux_inode_mkdir(struct inode *dir, struct dentry *dentry, int mask)
2624 {
2625 return may_create(dir, dentry, SECCLASS_DIR);
2626 }
2627
2628 static int selinux_inode_rmdir(struct inode *dir, struct dentry *dentry)
2629 {
2630 return may_link(dir, dentry, MAY_RMDIR);
2631 }
2632
2633 static int selinux_inode_mknod(struct inode *dir, struct dentry *dentry, int mode, dev_t dev)
2634 {
2635 return may_create(dir, dentry, inode_mode_to_security_class(mode));
2636 }
2637
2638 static int selinux_inode_rename(struct inode *old_inode, struct dentry *old_dentry,
2639 struct inode *new_inode, struct dentry *new_dentry)
2640 {
2641 return may_rename(old_inode, old_dentry, new_inode, new_dentry);
2642 }
2643
2644 static int selinux_inode_readlink(struct dentry *dentry)
2645 {
2646 const struct cred *cred = current_cred();
2647
2648 return dentry_has_perm(cred, dentry, FILE__READ);
2649 }
2650
2651 static int selinux_inode_follow_link(struct dentry *dentry, struct nameidata *nameidata)
2652 {
2653 const struct cred *cred = current_cred();
2654
2655 return dentry_has_perm(cred, dentry, FILE__READ);
2656 }
2657
2658 static int selinux_inode_permission(struct inode *inode, int mask)
2659 {
2660 const struct cred *cred = current_cred();
2661 struct common_audit_data ad;
2662 u32 perms;
2663 bool from_access;
2664 unsigned flags = mask & MAY_NOT_BLOCK;
2665
2666 from_access = mask & MAY_ACCESS;
2667 mask &= (MAY_READ|MAY_WRITE|MAY_EXEC|MAY_APPEND);
2668
2669 /* No permission to check. Existence test. */
2670 if (!mask)
2671 return 0;
2672
2673 COMMON_AUDIT_DATA_INIT(&ad, INODE);
2674 ad.u.inode = inode;
2675
2676 if (from_access)
2677 ad.selinux_audit_data.auditdeny |= FILE__AUDIT_ACCESS;
2678
2679 perms = file_mask_to_av(inode->i_mode, mask);
2680
2681 return inode_has_perm(cred, inode, perms, &ad, flags);
2682 }
2683
2684 static int selinux_inode_setattr(struct dentry *dentry, struct iattr *iattr)
2685 {
2686 const struct cred *cred = current_cred();
2687 unsigned int ia_valid = iattr->ia_valid;
2688
2689 /* ATTR_FORCE is just used for ATTR_KILL_S[UG]ID. */
2690 if (ia_valid & ATTR_FORCE) {
2691 ia_valid &= ~(ATTR_KILL_SUID | ATTR_KILL_SGID | ATTR_MODE |
2692 ATTR_FORCE);
2693 if (!ia_valid)
2694 return 0;
2695 }
2696
2697 if (ia_valid & (ATTR_MODE | ATTR_UID | ATTR_GID |
2698 ATTR_ATIME_SET | ATTR_MTIME_SET | ATTR_TIMES_SET))
2699 return dentry_has_perm(cred, dentry, FILE__SETATTR);
2700
2701 return dentry_has_perm(cred, dentry, FILE__WRITE);
2702 }
2703
2704 static int selinux_inode_getattr(struct vfsmount *mnt, struct dentry *dentry)
2705 {
2706 const struct cred *cred = current_cred();
2707 struct path path;
2708
2709 path.dentry = dentry;
2710 path.mnt = mnt;
2711
2712 return path_has_perm(cred, &path, FILE__GETATTR);
2713 }
2714
2715 static int selinux_inode_setotherxattr(struct dentry *dentry, const char *name)
2716 {
2717 const struct cred *cred = current_cred();
2718
2719 if (!strncmp(name, XATTR_SECURITY_PREFIX,
2720 sizeof XATTR_SECURITY_PREFIX - 1)) {
2721 if (!strcmp(name, XATTR_NAME_CAPS)) {
2722 if (!capable(CAP_SETFCAP))
2723 return -EPERM;
2724 } else if (!capable(CAP_SYS_ADMIN)) {
2725 /* A different attribute in the security namespace.
2726 Restrict to administrator. */
2727 return -EPERM;
2728 }
2729 }
2730
2731 /* Not an attribute we recognize, so just check the
2732 ordinary setattr permission. */
2733 return dentry_has_perm(cred, dentry, FILE__SETATTR);
2734 }
2735
2736 static int selinux_inode_setxattr(struct dentry *dentry, const char *name,
2737 const void *value, size_t size, int flags)
2738 {
2739 struct inode *inode = dentry->d_inode;
2740 struct inode_security_struct *isec = inode->i_security;
2741 struct superblock_security_struct *sbsec;
2742 struct common_audit_data ad;
2743 u32 newsid, sid = current_sid();
2744 int rc = 0;
2745
2746 if (strcmp(name, XATTR_NAME_SELINUX))
2747 return selinux_inode_setotherxattr(dentry, name);
2748
2749 sbsec = inode->i_sb->s_security;
2750 if (!(sbsec->flags & SE_SBLABELSUPP))
2751 return -EOPNOTSUPP;
2752
2753 if (!inode_owner_or_capable(inode))
2754 return -EPERM;
2755
2756 COMMON_AUDIT_DATA_INIT(&ad, DENTRY);
2757 ad.u.dentry = dentry;
2758
2759 rc = avc_has_perm(sid, isec->sid, isec->sclass,
2760 FILE__RELABELFROM, &ad);
2761 if (rc)
2762 return rc;
2763
2764 rc = security_context_to_sid(value, size, &newsid);
2765 if (rc == -EINVAL) {
2766 if (!capable(CAP_MAC_ADMIN))
2767 return rc;
2768 rc = security_context_to_sid_force(value, size, &newsid);
2769 }
2770 if (rc)
2771 return rc;
2772
2773 rc = avc_has_perm(sid, newsid, isec->sclass,
2774 FILE__RELABELTO, &ad);
2775 if (rc)
2776 return rc;
2777
2778 rc = security_validate_transition(isec->sid, newsid, sid,
2779 isec->sclass);
2780 if (rc)
2781 return rc;
2782
2783 return avc_has_perm(newsid,
2784 sbsec->sid,
2785 SECCLASS_FILESYSTEM,
2786 FILESYSTEM__ASSOCIATE,
2787 &ad);
2788 }
2789
2790 static void selinux_inode_post_setxattr(struct dentry *dentry, const char *name,
2791 const void *value, size_t size,
2792 int flags)
2793 {
2794 struct inode *inode = dentry->d_inode;
2795 struct inode_security_struct *isec = inode->i_security;
2796 u32 newsid;
2797 int rc;
2798
2799 if (strcmp(name, XATTR_NAME_SELINUX)) {
2800 /* Not an attribute we recognize, so nothing to do. */
2801 return;
2802 }
2803
2804 rc = security_context_to_sid_force(value, size, &newsid);
2805 if (rc) {
2806 printk(KERN_ERR "SELinux: unable to map context to SID"
2807 "for (%s, %lu), rc=%d\n",
2808 inode->i_sb->s_id, inode->i_ino, -rc);
2809 return;
2810 }
2811
2812 isec->sid = newsid;
2813 return;
2814 }
2815
2816 static int selinux_inode_getxattr(struct dentry *dentry, const char *name)
2817 {
2818 const struct cred *cred = current_cred();
2819
2820 return dentry_has_perm(cred, dentry, FILE__GETATTR);
2821 }
2822
2823 static int selinux_inode_listxattr(struct dentry *dentry)
2824 {
2825 const struct cred *cred = current_cred();
2826
2827 return dentry_has_perm(cred, dentry, FILE__GETATTR);
2828 }
2829
2830 static int selinux_inode_removexattr(struct dentry *dentry, const char *name)
2831 {
2832 if (strcmp(name, XATTR_NAME_SELINUX))
2833 return selinux_inode_setotherxattr(dentry, name);
2834
2835 /* No one is allowed to remove a SELinux security label.
2836 You can change the label, but all data must be labeled. */
2837 return -EACCES;
2838 }
2839
2840 /*
2841 * Copy the inode security context value to the user.
2842 *
2843 * Permission check is handled by selinux_inode_getxattr hook.
2844 */
2845 static int selinux_inode_getsecurity(const struct inode *inode, const char *name, void **buffer, bool alloc)
2846 {
2847 u32 size;
2848 int error;
2849 char *context = NULL;
2850 struct inode_security_struct *isec = inode->i_security;
2851
2852 if (strcmp(name, XATTR_SELINUX_SUFFIX))
2853 return -EOPNOTSUPP;
2854
2855 /*
2856 * If the caller has CAP_MAC_ADMIN, then get the raw context
2857 * value even if it is not defined by current policy; otherwise,
2858 * use the in-core value under current policy.
2859 * Use the non-auditing forms of the permission checks since
2860 * getxattr may be called by unprivileged processes commonly
2861 * and lack of permission just means that we fall back to the
2862 * in-core context value, not a denial.
2863 */
2864 error = selinux_capable(current, current_cred(),
2865 &init_user_ns, CAP_MAC_ADMIN,
2866 SECURITY_CAP_NOAUDIT);
2867 if (!error)
2868 error = security_sid_to_context_force(isec->sid, &context,
2869 &size);
2870 else
2871 error = security_sid_to_context(isec->sid, &context, &size);
2872 if (error)
2873 return error;
2874 error = size;
2875 if (alloc) {
2876 *buffer = context;
2877 goto out_nofree;
2878 }
2879 kfree(context);
2880 out_nofree:
2881 return error;
2882 }
2883
2884 static int selinux_inode_setsecurity(struct inode *inode, const char *name,
2885 const void *value, size_t size, int flags)
2886 {
2887 struct inode_security_struct *isec = inode->i_security;
2888 u32 newsid;
2889 int rc;
2890
2891 if (strcmp(name, XATTR_SELINUX_SUFFIX))
2892 return -EOPNOTSUPP;
2893
2894 if (!value || !size)
2895 return -EACCES;
2896
2897 rc = security_context_to_sid((void *)value, size, &newsid);
2898 if (rc)
2899 return rc;
2900
2901 isec->sid = newsid;
2902 isec->initialized = 1;
2903 return 0;
2904 }
2905
2906 static int selinux_inode_listsecurity(struct inode *inode, char *buffer, size_t buffer_size)
2907 {
2908 const int len = sizeof(XATTR_NAME_SELINUX);
2909 if (buffer && len <= buffer_size)
2910 memcpy(buffer, XATTR_NAME_SELINUX, len);
2911 return len;
2912 }
2913
2914 static void selinux_inode_getsecid(const struct inode *inode, u32 *secid)
2915 {
2916 struct inode_security_struct *isec = inode->i_security;
2917 *secid = isec->sid;
2918 }
2919
2920 /* file security operations */
2921
2922 static int selinux_revalidate_file_permission(struct file *file, int mask)
2923 {
2924 const struct cred *cred = current_cred();
2925 struct inode *inode = file->f_path.dentry->d_inode;
2926
2927 /* file_mask_to_av won't add FILE__WRITE if MAY_APPEND is set */
2928 if ((file->f_flags & O_APPEND) && (mask & MAY_WRITE))
2929 mask |= MAY_APPEND;
2930
2931 return file_has_perm(cred, file,
2932 file_mask_to_av(inode->i_mode, mask));
2933 }
2934
2935 static int selinux_file_permission(struct file *file, int mask)
2936 {
2937 struct inode *inode = file->f_path.dentry->d_inode;
2938 struct file_security_struct *fsec = file->f_security;
2939 struct inode_security_struct *isec = inode->i_security;
2940 u32 sid = current_sid();
2941
2942 if (!mask)
2943 /* No permission to check. Existence test. */
2944 return 0;
2945
2946 if (sid == fsec->sid && fsec->isid == isec->sid &&
2947 fsec->pseqno == avc_policy_seqno())
2948 /* No change since dentry_open check. */
2949 return 0;
2950
2951 return selinux_revalidate_file_permission(file, mask);
2952 }
2953
2954 static int selinux_file_alloc_security(struct file *file)
2955 {
2956 return file_alloc_security(file);
2957 }
2958
2959 static void selinux_file_free_security(struct file *file)
2960 {
2961 file_free_security(file);
2962 }
2963
2964 static int selinux_file_ioctl(struct file *file, unsigned int cmd,
2965 unsigned long arg)
2966 {
2967 const struct cred *cred = current_cred();
2968 int error = 0;
2969
2970 switch (cmd) {
2971 case FIONREAD:
2972 /* fall through */
2973 case FIBMAP:
2974 /* fall through */
2975 case FIGETBSZ:
2976 /* fall through */
2977 case EXT2_IOC_GETFLAGS:
2978 /* fall through */
2979 case EXT2_IOC_GETVERSION:
2980 error = file_has_perm(cred, file, FILE__GETATTR);
2981 break;
2982
2983 case EXT2_IOC_SETFLAGS:
2984 /* fall through */
2985 case EXT2_IOC_SETVERSION:
2986 error = file_has_perm(cred, file, FILE__SETATTR);
2987 break;
2988
2989 /* sys_ioctl() checks */
2990 case FIONBIO:
2991 /* fall through */
2992 case FIOASYNC:
2993 error = file_has_perm(cred, file, 0);
2994 break;
2995
2996 case KDSKBENT:
2997 case KDSKBSENT:
2998 error = task_has_capability(current, cred, CAP_SYS_TTY_CONFIG,
2999 SECURITY_CAP_AUDIT);
3000 break;
3001
3002 /* default case assumes that the command will go
3003 * to the file's ioctl() function.
3004 */
3005 default:
3006 error = file_has_perm(cred, file, FILE__IOCTL);
3007 }
3008 return error;
3009 }
3010
3011 static int default_noexec;
3012
3013 static int file_map_prot_check(struct file *file, unsigned long prot, int shared)
3014 {
3015 const struct cred *cred = current_cred();
3016 int rc = 0;
3017
3018 if (default_noexec &&
3019 (prot & PROT_EXEC) && (!file || (!shared && (prot & PROT_WRITE)))) {
3020 /*
3021 * We are making executable an anonymous mapping or a
3022 * private file mapping that will also be writable.
3023 * This has an additional check.
3024 */
3025 rc = cred_has_perm(cred, cred, PROCESS__EXECMEM);
3026 if (rc)
3027 goto error;
3028 }
3029
3030 if (file) {
3031 /* read access is always possible with a mapping */
3032 u32 av = FILE__READ;
3033
3034 /* write access only matters if the mapping is shared */
3035 if (shared && (prot & PROT_WRITE))
3036 av |= FILE__WRITE;
3037
3038 if (prot & PROT_EXEC)
3039 av |= FILE__EXECUTE;
3040
3041 return file_has_perm(cred, file, av);
3042 }
3043
3044 error:
3045 return rc;
3046 }
3047
3048 static int selinux_file_mmap(struct file *file, unsigned long reqprot,
3049 unsigned long prot, unsigned long flags,
3050 unsigned long addr, unsigned long addr_only)
3051 {
3052 int rc = 0;
3053 u32 sid = current_sid();
3054
3055 /*
3056 * notice that we are intentionally putting the SELinux check before
3057 * the secondary cap_file_mmap check. This is such a likely attempt
3058 * at bad behaviour/exploit that we always want to get the AVC, even
3059 * if DAC would have also denied the operation.
3060 */
3061 if (addr < CONFIG_LSM_MMAP_MIN_ADDR) {
3062 rc = avc_has_perm(sid, sid, SECCLASS_MEMPROTECT,
3063 MEMPROTECT__MMAP_ZERO, NULL);
3064 if (rc)
3065 return rc;
3066 }
3067
3068 /* do DAC check on address space usage */
3069 rc = cap_file_mmap(file, reqprot, prot, flags, addr, addr_only);
3070 if (rc || addr_only)
3071 return rc;
3072
3073 if (selinux_checkreqprot)
3074 prot = reqprot;
3075
3076 return file_map_prot_check(file, prot,
3077 (flags & MAP_TYPE) == MAP_SHARED);
3078 }
3079
3080 static int selinux_file_mprotect(struct vm_area_struct *vma,
3081 unsigned long reqprot,
3082 unsigned long prot)
3083 {
3084 const struct cred *cred = current_cred();
3085
3086 if (selinux_checkreqprot)
3087 prot = reqprot;
3088
3089 if (default_noexec &&
3090 (prot & PROT_EXEC) && !(vma->vm_flags & VM_EXEC)) {
3091 int rc = 0;
3092 if (vma->vm_start >= vma->vm_mm->start_brk &&
3093 vma->vm_end <= vma->vm_mm->brk) {
3094 rc = cred_has_perm(cred, cred, PROCESS__EXECHEAP);
3095 } else if (!vma->vm_file &&
3096 vma->vm_start <= vma->vm_mm->start_stack &&
3097 vma->vm_end >= vma->vm_mm->start_stack) {
3098 rc = current_has_perm(current, PROCESS__EXECSTACK);
3099 } else if (vma->vm_file && vma->anon_vma) {
3100 /*
3101 * We are making executable a file mapping that has
3102 * had some COW done. Since pages might have been
3103 * written, check ability to execute the possibly
3104 * modified content. This typically should only
3105 * occur for text relocations.
3106 */
3107 rc = file_has_perm(cred, vma->vm_file, FILE__EXECMOD);
3108 }
3109 if (rc)
3110 return rc;
3111 }
3112
3113 return file_map_prot_check(vma->vm_file, prot, vma->vm_flags&VM_SHARED);
3114 }
3115
3116 static int selinux_file_lock(struct file *file, unsigned int cmd)
3117 {
3118 const struct cred *cred = current_cred();
3119
3120 return file_has_perm(cred, file, FILE__LOCK);
3121 }
3122
3123 static int selinux_file_fcntl(struct file *file, unsigned int cmd,
3124 unsigned long arg)
3125 {
3126 const struct cred *cred = current_cred();
3127 int err = 0;
3128
3129 switch (cmd) {
3130 case F_SETFL:
3131 if (!file->f_path.dentry || !file->f_path.dentry->d_inode) {
3132 err = -EINVAL;
3133 break;
3134 }
3135
3136 if ((file->f_flags & O_APPEND) && !(arg & O_APPEND)) {
3137 err = file_has_perm(cred, file, FILE__WRITE);
3138 break;
3139 }
3140 /* fall through */
3141 case F_SETOWN:
3142 case F_SETSIG:
3143 case F_GETFL:
3144 case F_GETOWN:
3145 case F_GETSIG:
3146 /* Just check FD__USE permission */
3147 err = file_has_perm(cred, file, 0);
3148 break;
3149 case F_GETLK:
3150 case F_SETLK:
3151 case F_SETLKW:
3152 #if BITS_PER_LONG == 32
3153 case F_GETLK64:
3154 case F_SETLK64:
3155 case F_SETLKW64:
3156 #endif
3157 if (!file->f_path.dentry || !file->f_path.dentry->d_inode) {
3158 err = -EINVAL;
3159 break;
3160 }
3161 err = file_has_perm(cred, file, FILE__LOCK);
3162 break;
3163 }
3164
3165 return err;
3166 }
3167
3168 static int selinux_file_set_fowner(struct file *file)
3169 {
3170 struct file_security_struct *fsec;
3171
3172 fsec = file->f_security;
3173 fsec->fown_sid = current_sid();
3174
3175 return 0;
3176 }
3177
3178 static int selinux_file_send_sigiotask(struct task_struct *tsk,
3179 struct fown_struct *fown, int signum)
3180 {
3181 struct file *file;
3182 u32 sid = task_sid(tsk);
3183 u32 perm;
3184 struct file_security_struct *fsec;
3185
3186 /* struct fown_struct is never outside the context of a struct file */
3187 file = container_of(fown, struct file, f_owner);
3188
3189 fsec = file->f_security;
3190
3191 if (!signum)
3192 perm = signal_to_av(SIGIO); /* as per send_sigio_to_task */
3193 else
3194 perm = signal_to_av(signum);
3195
3196 return avc_has_perm(fsec->fown_sid, sid,
3197 SECCLASS_PROCESS, perm, NULL);
3198 }
3199
3200 static int selinux_file_receive(struct file *file)
3201 {
3202 const struct cred *cred = current_cred();
3203
3204 return file_has_perm(cred, file, file_to_av(file));
3205 }
3206
3207 static int selinux_dentry_open(struct file *file, const struct cred *cred)
3208 {
3209 struct file_security_struct *fsec;
3210 struct inode *inode;
3211 struct inode_security_struct *isec;
3212
3213 inode = file->f_path.dentry->d_inode;
3214 fsec = file->f_security;
3215 isec = inode->i_security;
3216 /*
3217 * Save inode label and policy sequence number
3218 * at open-time so that selinux_file_permission
3219 * can determine whether revalidation is necessary.
3220 * Task label is already saved in the file security
3221 * struct as its SID.
3222 */
3223 fsec->isid = isec->sid;
3224 fsec->pseqno = avc_policy_seqno();
3225 /*
3226 * Since the inode label or policy seqno may have changed
3227 * between the selinux_inode_permission check and the saving
3228 * of state above, recheck that access is still permitted.
3229 * Otherwise, access might never be revalidated against the
3230 * new inode label or new policy.
3231 * This check is not redundant - do not remove.
3232 */
3233 return inode_has_perm_noadp(cred, inode, open_file_to_av(file), 0);
3234 }
3235
3236 /* task security operations */
3237
3238 static int selinux_task_create(unsigned long clone_flags)
3239 {
3240 return current_has_perm(current, PROCESS__FORK);
3241 }
3242
3243 /*
3244 * allocate the SELinux part of blank credentials
3245 */
3246 static int selinux_cred_alloc_blank(struct cred *cred, gfp_t gfp)
3247 {
3248 struct task_security_struct *tsec;
3249
3250 tsec = kzalloc(sizeof(struct task_security_struct), gfp);
3251 if (!tsec)
3252 return -ENOMEM;
3253
3254 cred->security = tsec;
3255 return 0;
3256 }
3257
3258 /*
3259 * detach and free the LSM part of a set of credentials
3260 */
3261 static void selinux_cred_free(struct cred *cred)
3262 {
3263 struct task_security_struct *tsec = cred->security;
3264
3265 /*
3266 * cred->security == NULL if security_cred_alloc_blank() or
3267 * security_prepare_creds() returned an error.
3268 */
3269 BUG_ON(cred->security && (unsigned long) cred->security < PAGE_SIZE);
3270 cred->security = (void *) 0x7UL;
3271 kfree(tsec);
3272 }
3273
3274 /*
3275 * prepare a new set of credentials for modification
3276 */
3277 static int selinux_cred_prepare(struct cred *new, const struct cred *old,
3278 gfp_t gfp)
3279 {
3280 const struct task_security_struct *old_tsec;
3281 struct task_security_struct *tsec;
3282
3283 old_tsec = old->security;
3284
3285 tsec = kmemdup(old_tsec, sizeof(struct task_security_struct), gfp);
3286 if (!tsec)
3287 return -ENOMEM;
3288
3289 new->security = tsec;
3290 return 0;
3291 }
3292
3293 /*
3294 * transfer the SELinux data to a blank set of creds
3295 */
3296 static void selinux_cred_transfer(struct cred *new, const struct cred *old)
3297 {
3298 const struct task_security_struct *old_tsec = old->security;
3299 struct task_security_struct *tsec = new->security;
3300
3301 *tsec = *old_tsec;
3302 }
3303
3304 /*
3305 * set the security data for a kernel service
3306 * - all the creation contexts are set to unlabelled
3307 */
3308 static int selinux_kernel_act_as(struct cred *new, u32 secid)
3309 {
3310 struct task_security_struct *tsec = new->security;
3311 u32 sid = current_sid();
3312 int ret;
3313
3314 ret = avc_has_perm(sid, secid,
3315 SECCLASS_KERNEL_SERVICE,
3316 KERNEL_SERVICE__USE_AS_OVERRIDE,
3317 NULL);
3318 if (ret == 0) {
3319 tsec->sid = secid;
3320 tsec->create_sid = 0;
3321 tsec->keycreate_sid = 0;
3322 tsec->sockcreate_sid = 0;
3323 }
3324 return ret;
3325 }
3326
3327 /*
3328 * set the file creation context in a security record to the same as the
3329 * objective context of the specified inode
3330 */
3331 static int selinux_kernel_create_files_as(struct cred *new, struct inode *inode)
3332 {
3333 struct inode_security_struct *isec = inode->i_security;
3334 struct task_security_struct *tsec = new->security;
3335 u32 sid = current_sid();
3336 int ret;
3337
3338 ret = avc_has_perm(sid, isec->sid,
3339 SECCLASS_KERNEL_SERVICE,
3340 KERNEL_SERVICE__CREATE_FILES_AS,
3341 NULL);
3342
3343 if (ret == 0)
3344 tsec->create_sid = isec->sid;
3345 return ret;
3346 }
3347
3348 static int selinux_kernel_module_request(char *kmod_name)
3349 {
3350 u32 sid;
3351 struct common_audit_data ad;
3352
3353 sid = task_sid(current);
3354
3355 COMMON_AUDIT_DATA_INIT(&ad, KMOD);
3356 ad.u.kmod_name = kmod_name;
3357
3358 return avc_has_perm(sid, SECINITSID_KERNEL, SECCLASS_SYSTEM,
3359 SYSTEM__MODULE_REQUEST, &ad);
3360 }
3361
3362 static int selinux_task_setpgid(struct task_struct *p, pid_t pgid)
3363 {
3364 return current_has_perm(p, PROCESS__SETPGID);
3365 }
3366
3367 static int selinux_task_getpgid(struct task_struct *p)
3368 {
3369 return current_has_perm(p, PROCESS__GETPGID);
3370 }
3371
3372 static int selinux_task_getsid(struct task_struct *p)
3373 {
3374 return current_has_perm(p, PROCESS__GETSESSION);
3375 }
3376
3377 static void selinux_task_getsecid(struct task_struct *p, u32 *secid)
3378 {
3379 *secid = task_sid(p);
3380 }
3381
3382 static int selinux_task_setnice(struct task_struct *p, int nice)
3383 {
3384 int rc;
3385
3386 rc = cap_task_setnice(p, nice);
3387 if (rc)
3388 return rc;
3389
3390 return current_has_perm(p, PROCESS__SETSCHED);
3391 }
3392
3393 static int selinux_task_setioprio(struct task_struct *p, int ioprio)
3394 {
3395 int rc;
3396
3397 rc = cap_task_setioprio(p, ioprio);
3398 if (rc)
3399 return rc;
3400
3401 return current_has_perm(p, PROCESS__SETSCHED);
3402 }
3403
3404 static int selinux_task_getioprio(struct task_struct *p)
3405 {
3406 return current_has_perm(p, PROCESS__GETSCHED);
3407 }
3408
3409 static int selinux_task_setrlimit(struct task_struct *p, unsigned int resource,
3410 struct rlimit *new_rlim)
3411 {
3412 struct rlimit *old_rlim = p->signal->rlim + resource;
3413
3414 /* Control the ability to change the hard limit (whether
3415 lowering or raising it), so that the hard limit can
3416 later be used as a safe reset point for the soft limit
3417 upon context transitions. See selinux_bprm_committing_creds. */
3418 if (old_rlim->rlim_max != new_rlim->rlim_max)
3419 return current_has_perm(p, PROCESS__SETRLIMIT);
3420
3421 return 0;
3422 }
3423
3424 static int selinux_task_setscheduler(struct task_struct *p)
3425 {
3426 int rc;
3427
3428 rc = cap_task_setscheduler(p);
3429 if (rc)
3430 return rc;
3431
3432 return current_has_perm(p, PROCESS__SETSCHED);
3433 }
3434
3435 static int selinux_task_getscheduler(struct task_struct *p)
3436 {
3437 return current_has_perm(p, PROCESS__GETSCHED);
3438 }
3439
3440 static int selinux_task_movememory(struct task_struct *p)
3441 {
3442 return current_has_perm(p, PROCESS__SETSCHED);
3443 }
3444
3445 static int selinux_task_kill(struct task_struct *p, struct siginfo *info,
3446 int sig, u32 secid)
3447 {
3448 u32 perm;
3449 int rc;
3450
3451 if (!sig)
3452 perm = PROCESS__SIGNULL; /* null signal; existence test */
3453 else
3454 perm = signal_to_av(sig);
3455 if (secid)
3456 rc = avc_has_perm(secid, task_sid(p),
3457 SECCLASS_PROCESS, perm, NULL);
3458 else
3459 rc = current_has_perm(p, perm);
3460 return rc;
3461 }
3462
3463 static int selinux_task_wait(struct task_struct *p)
3464 {
3465 return task_has_perm(p, current, PROCESS__SIGCHLD);
3466 }
3467
3468 static void selinux_task_to_inode(struct task_struct *p,
3469 struct inode *inode)
3470 {
3471 struct inode_security_struct *isec = inode->i_security;
3472 u32 sid = task_sid(p);
3473
3474 isec->sid = sid;
3475 isec->initialized = 1;
3476 }
3477
3478 /* Returns error only if unable to parse addresses */
3479 static int selinux_parse_skb_ipv4(struct sk_buff *skb,
3480 struct common_audit_data *ad, u8 *proto)
3481 {
3482 int offset, ihlen, ret = -EINVAL;
3483 struct iphdr _iph, *ih;
3484
3485 offset = skb_network_offset(skb);
3486 ih = skb_header_pointer(skb, offset, sizeof(_iph), &_iph);
3487 if (ih == NULL)
3488 goto out;
3489
3490 ihlen = ih->ihl * 4;
3491 if (ihlen < sizeof(_iph))
3492 goto out;
3493
3494 ad->u.net.v4info.saddr = ih->saddr;
3495 ad->u.net.v4info.daddr = ih->daddr;
3496 ret = 0;
3497
3498 if (proto)
3499 *proto = ih->protocol;
3500
3501 switch (ih->protocol) {
3502 case IPPROTO_TCP: {
3503 struct tcphdr _tcph, *th;
3504
3505 if (ntohs(ih->frag_off) & IP_OFFSET)
3506 break;
3507
3508 offset += ihlen;
3509 th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph);
3510 if (th == NULL)
3511 break;
3512
3513 ad->u.net.sport = th->source;
3514 ad->u.net.dport = th->dest;
3515 break;
3516 }
3517
3518 case IPPROTO_UDP: {
3519 struct udphdr _udph, *uh;
3520
3521 if (ntohs(ih->frag_off) & IP_OFFSET)
3522 break;
3523
3524 offset += ihlen;
3525 uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph);
3526 if (uh == NULL)
3527 break;
3528
3529 ad->u.net.sport = uh->source;
3530 ad->u.net.dport = uh->dest;
3531 break;
3532 }
3533
3534 case IPPROTO_DCCP: {
3535 struct dccp_hdr _dccph, *dh;
3536
3537 if (ntohs(ih->frag_off) & IP_OFFSET)
3538 break;
3539
3540 offset += ihlen;
3541 dh = skb_header_pointer(skb, offset, sizeof(_dccph), &_dccph);
3542 if (dh == NULL)
3543 break;
3544
3545 ad->u.net.sport = dh->dccph_sport;
3546 ad->u.net.dport = dh->dccph_dport;
3547 break;
3548 }
3549
3550 default:
3551 break;
3552 }
3553 out:
3554 return ret;
3555 }
3556
3557 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
3558
3559 /* Returns error only if unable to parse addresses */
3560 static int selinux_parse_skb_ipv6(struct sk_buff *skb,
3561 struct common_audit_data *ad, u8 *proto)
3562 {
3563 u8 nexthdr;
3564 int ret = -EINVAL, offset;
3565 struct ipv6hdr _ipv6h, *ip6;
3566
3567 offset = skb_network_offset(skb);
3568 ip6 = skb_header_pointer(skb, offset, sizeof(_ipv6h), &_ipv6h);
3569 if (ip6 == NULL)
3570 goto out;
3571
3572 ipv6_addr_copy(&ad->u.net.v6info.saddr, &ip6->saddr);
3573 ipv6_addr_copy(&ad->u.net.v6info.daddr, &ip6->daddr);
3574 ret = 0;
3575
3576 nexthdr = ip6->nexthdr;
3577 offset += sizeof(_ipv6h);
3578 offset = ipv6_skip_exthdr(skb, offset, &nexthdr);
3579 if (offset < 0)
3580 goto out;
3581
3582 if (proto)
3583 *proto = nexthdr;
3584
3585 switch (nexthdr) {
3586 case IPPROTO_TCP: {
3587 struct tcphdr _tcph, *th;
3588
3589 th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph);
3590 if (th == NULL)
3591 break;
3592
3593 ad->u.net.sport = th->source;
3594 ad->u.net.dport = th->dest;
3595 break;
3596 }
3597
3598 case IPPROTO_UDP: {
3599 struct udphdr _udph, *uh;
3600
3601 uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph);
3602 if (uh == NULL)
3603 break;
3604
3605 ad->u.net.sport = uh->source;
3606 ad->u.net.dport = uh->dest;
3607 break;
3608 }
3609
3610 case IPPROTO_DCCP: {
3611 struct dccp_hdr _dccph, *dh;
3612
3613 dh = skb_header_pointer(skb, offset, sizeof(_dccph), &_dccph);
3614 if (dh == NULL)
3615 break;
3616
3617 ad->u.net.sport = dh->dccph_sport;
3618 ad->u.net.dport = dh->dccph_dport;
3619 break;
3620 }
3621
3622 /* includes fragments */
3623 default:
3624 break;
3625 }
3626 out:
3627 return ret;
3628 }
3629
3630 #endif /* IPV6 */
3631
3632 static int selinux_parse_skb(struct sk_buff *skb, struct common_audit_data *ad,
3633 char **_addrp, int src, u8 *proto)
3634 {
3635 char *addrp;
3636 int ret;
3637
3638 switch (ad->u.net.family) {
3639 case PF_INET:
3640 ret = selinux_parse_skb_ipv4(skb, ad, proto);
3641 if (ret)
3642 goto parse_error;
3643 addrp = (char *)(src ? &ad->u.net.v4info.saddr :
3644 &ad->u.net.v4info.daddr);
3645 goto okay;
3646
3647 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
3648 case PF_INET6:
3649 ret = selinux_parse_skb_ipv6(skb, ad, proto);
3650 if (ret)
3651 goto parse_error;
3652 addrp = (char *)(src ? &ad->u.net.v6info.saddr :
3653 &ad->u.net.v6info.daddr);
3654 goto okay;
3655 #endif /* IPV6 */
3656 default:
3657 addrp = NULL;
3658 goto okay;
3659 }
3660
3661 parse_error:
3662 printk(KERN_WARNING
3663 "SELinux: failure in selinux_parse_skb(),"
3664 " unable to parse packet\n");
3665 return ret;
3666
3667 okay:
3668 if (_addrp)
3669 *_addrp = addrp;
3670 return 0;
3671 }
3672
3673 /**
3674 * selinux_skb_peerlbl_sid - Determine the peer label of a packet
3675 * @skb: the packet
3676 * @family: protocol family
3677 * @sid: the packet's peer label SID
3678 *
3679 * Description:
3680 * Check the various different forms of network peer labeling and determine
3681 * the peer label/SID for the packet; most of the magic actually occurs in
3682 * the security server function security_net_peersid_cmp(). The function
3683 * returns zero if the value in @sid is valid (although it may be SECSID_NULL)
3684 * or -EACCES if @sid is invalid due to inconsistencies with the different
3685 * peer labels.
3686 *
3687 */
3688 static int selinux_skb_peerlbl_sid(struct sk_buff *skb, u16 family, u32 *sid)
3689 {
3690 int err;
3691 u32 xfrm_sid;
3692 u32 nlbl_sid;
3693 u32 nlbl_type;
3694
3695 selinux_skb_xfrm_sid(skb, &xfrm_sid);
3696 selinux_netlbl_skbuff_getsid(skb, family, &nlbl_type, &nlbl_sid);
3697
3698 err = security_net_peersid_resolve(nlbl_sid, nlbl_type, xfrm_sid, sid);
3699 if (unlikely(err)) {
3700 printk(KERN_WARNING
3701 "SELinux: failure in selinux_skb_peerlbl_sid(),"
3702 " unable to determine packet's peer label\n");
3703 return -EACCES;
3704 }
3705
3706 return 0;
3707 }
3708
3709 /* socket security operations */
3710
3711 static int socket_sockcreate_sid(const struct task_security_struct *tsec,
3712 u16 secclass, u32 *socksid)
3713 {
3714 if (tsec->sockcreate_sid > SECSID_NULL) {
3715 *socksid = tsec->sockcreate_sid;
3716 return 0;
3717 }
3718
3719 return security_transition_sid(tsec->sid, tsec->sid, secclass, NULL,
3720 socksid);
3721 }
3722
3723 static int sock_has_perm(struct task_struct *task, struct sock *sk, u32 perms)
3724 {
3725 struct sk_security_struct *sksec = sk->sk_security;
3726 struct common_audit_data ad;
3727 u32 tsid = task_sid(task);
3728
3729 if (sksec->sid == SECINITSID_KERNEL)
3730 return 0;
3731
3732 COMMON_AUDIT_DATA_INIT(&ad, NET);
3733 ad.u.net.sk = sk;
3734
3735 return avc_has_perm(tsid, sksec->sid, sksec->sclass, perms, &ad);
3736 }
3737
3738 static int selinux_socket_create(int family, int type,
3739 int protocol, int kern)
3740 {
3741 const struct task_security_struct *tsec = current_security();
3742 u32 newsid;
3743 u16 secclass;
3744 int rc;
3745
3746 if (kern)
3747 return 0;
3748
3749 secclass = socket_type_to_security_class(family, type, protocol);
3750 rc = socket_sockcreate_sid(tsec, secclass, &newsid);
3751 if (rc)
3752 return rc;
3753
3754 return avc_has_perm(tsec->sid, newsid, secclass, SOCKET__CREATE, NULL);
3755 }
3756
3757 static int selinux_socket_post_create(struct socket *sock, int family,
3758 int type, int protocol, int kern)
3759 {
3760 const struct task_security_struct *tsec = current_security();
3761 struct inode_security_struct *isec = SOCK_INODE(sock)->i_security;
3762 struct sk_security_struct *sksec;
3763 int err = 0;
3764
3765 isec->sclass = socket_type_to_security_class(family, type, protocol);
3766
3767 if (kern)
3768 isec->sid = SECINITSID_KERNEL;
3769 else {
3770 err = socket_sockcreate_sid(tsec, isec->sclass, &(isec->sid));
3771 if (err)
3772 return err;
3773 }
3774
3775 isec->initialized = 1;
3776
3777 if (sock->sk) {
3778 sksec = sock->sk->sk_security;
3779 sksec->sid = isec->sid;
3780 sksec->sclass = isec->sclass;
3781 err = selinux_netlbl_socket_post_create(sock->sk, family);
3782 }
3783
3784 return err;
3785 }
3786
3787 /* Range of port numbers used to automatically bind.
3788 Need to determine whether we should perform a name_bind
3789 permission check between the socket and the port number. */
3790
3791 static int selinux_socket_bind(struct socket *sock, struct sockaddr *address, int addrlen)
3792 {
3793 struct sock *sk = sock->sk;
3794 u16 family;
3795 int err;
3796
3797 err = sock_has_perm(current, sk, SOCKET__BIND);
3798 if (err)
3799 goto out;
3800
3801 /*
3802 * If PF_INET or PF_INET6, check name_bind permission for the port.
3803 * Multiple address binding for SCTP is not supported yet: we just
3804 * check the first address now.
3805 */
3806 family = sk->sk_family;
3807 if (family == PF_INET || family == PF_INET6) {
3808 char *addrp;
3809 struct sk_security_struct *sksec = sk->sk_security;
3810 struct common_audit_data ad;
3811 struct sockaddr_in *addr4 = NULL;
3812 struct sockaddr_in6 *addr6 = NULL;
3813 unsigned short snum;
3814 u32 sid, node_perm;
3815
3816 if (family == PF_INET) {
3817 addr4 = (struct sockaddr_in *)address;
3818 snum = ntohs(addr4->sin_port);
3819 addrp = (char *)&addr4->sin_addr.s_addr;
3820 } else {
3821 addr6 = (struct sockaddr_in6 *)address;
3822 snum = ntohs(addr6->sin6_port);
3823 addrp = (char *)&addr6->sin6_addr.s6_addr;
3824 }
3825
3826 if (snum) {
3827 int low, high;
3828
3829 inet_get_local_port_range(&low, &high);
3830
3831 if (snum < max(PROT_SOCK, low) || snum > high) {
3832 err = sel_netport_sid(sk->sk_protocol,
3833 snum, &sid);
3834 if (err)
3835 goto out;
3836 COMMON_AUDIT_DATA_INIT(&ad, NET);
3837 ad.u.net.sport = htons(snum);
3838 ad.u.net.family = family;
3839 err = avc_has_perm(sksec->sid, sid,
3840 sksec->sclass,
3841 SOCKET__NAME_BIND, &ad);
3842 if (err)
3843 goto out;
3844 }
3845 }
3846
3847 switch (sksec->sclass) {
3848 case SECCLASS_TCP_SOCKET:
3849 node_perm = TCP_SOCKET__NODE_BIND;
3850 break;
3851
3852 case SECCLASS_UDP_SOCKET:
3853 node_perm = UDP_SOCKET__NODE_BIND;
3854 break;
3855
3856 case SECCLASS_DCCP_SOCKET:
3857 node_perm = DCCP_SOCKET__NODE_BIND;
3858 break;
3859
3860 default:
3861 node_perm = RAWIP_SOCKET__NODE_BIND;
3862 break;
3863 }
3864
3865 err = sel_netnode_sid(addrp, family, &sid);
3866 if (err)
3867 goto out;
3868
3869 COMMON_AUDIT_DATA_INIT(&ad, NET);
3870 ad.u.net.sport = htons(snum);
3871 ad.u.net.family = family;
3872
3873 if (family == PF_INET)
3874 ad.u.net.v4info.saddr = addr4->sin_addr.s_addr;
3875 else
3876 ipv6_addr_copy(&ad.u.net.v6info.saddr, &addr6->sin6_addr);
3877
3878 err = avc_has_perm(sksec->sid, sid,
3879 sksec->sclass, node_perm, &ad);
3880 if (err)
3881 goto out;
3882 }
3883 out:
3884 return err;
3885 }
3886
3887 static int selinux_socket_connect(struct socket *sock, struct sockaddr *address, int addrlen)
3888 {
3889 struct sock *sk = sock->sk;
3890 struct sk_security_struct *sksec = sk->sk_security;
3891 int err;
3892
3893 err = sock_has_perm(current, sk, SOCKET__CONNECT);
3894 if (err)
3895 return err;
3896
3897 /*
3898 * If a TCP or DCCP socket, check name_connect permission for the port.
3899 */
3900 if (sksec->sclass == SECCLASS_TCP_SOCKET ||
3901 sksec->sclass == SECCLASS_DCCP_SOCKET) {
3902 struct common_audit_data ad;
3903 struct sockaddr_in *addr4 = NULL;
3904 struct sockaddr_in6 *addr6 = NULL;
3905 unsigned short snum;
3906 u32 sid, perm;
3907
3908 if (sk->sk_family == PF_INET) {
3909 addr4 = (struct sockaddr_in *)address;
3910 if (addrlen < sizeof(struct sockaddr_in))
3911 return -EINVAL;
3912 snum = ntohs(addr4->sin_port);
3913 } else {
3914 addr6 = (struct sockaddr_in6 *)address;
3915 if (addrlen < SIN6_LEN_RFC2133)
3916 return -EINVAL;
3917 snum = ntohs(addr6->sin6_port);
3918 }
3919
3920 err = sel_netport_sid(sk->sk_protocol, snum, &sid);
3921 if (err)
3922 goto out;
3923
3924 perm = (sksec->sclass == SECCLASS_TCP_SOCKET) ?
3925 TCP_SOCKET__NAME_CONNECT : DCCP_SOCKET__NAME_CONNECT;
3926
3927 COMMON_AUDIT_DATA_INIT(&ad, NET);
3928 ad.u.net.dport = htons(snum);
3929 ad.u.net.family = sk->sk_family;
3930 err = avc_has_perm(sksec->sid, sid, sksec->sclass, perm, &ad);
3931 if (err)
3932 goto out;
3933 }
3934
3935 err = selinux_netlbl_socket_connect(sk, address);
3936
3937 out:
3938 return err;
3939 }
3940
3941 static int selinux_socket_listen(struct socket *sock, int backlog)
3942 {
3943 return sock_has_perm(current, sock->sk, SOCKET__LISTEN);
3944 }
3945
3946 static int selinux_socket_accept(struct socket *sock, struct socket *newsock)
3947 {
3948 int err;
3949 struct inode_security_struct *isec;
3950 struct inode_security_struct *newisec;
3951
3952 err = sock_has_perm(current, sock->sk, SOCKET__ACCEPT);
3953 if (err)
3954 return err;
3955
3956 newisec = SOCK_INODE(newsock)->i_security;
3957
3958 isec = SOCK_INODE(sock)->i_security;
3959 newisec->sclass = isec->sclass;
3960 newisec->sid = isec->sid;
3961 newisec->initialized = 1;
3962
3963 return 0;
3964 }
3965
3966 static int selinux_socket_sendmsg(struct socket *sock, struct msghdr *msg,
3967 int size)
3968 {
3969 return sock_has_perm(current, sock->sk, SOCKET__WRITE);
3970 }
3971
3972 static int selinux_socket_recvmsg(struct socket *sock, struct msghdr *msg,
3973 int size, int flags)
3974 {
3975 return sock_has_perm(current, sock->sk, SOCKET__READ);
3976 }
3977
3978 static int selinux_socket_getsockname(struct socket *sock)
3979 {
3980 return sock_has_perm(current, sock->sk, SOCKET__GETATTR);
3981 }
3982
3983 static int selinux_socket_getpeername(struct socket *sock)
3984 {
3985 return sock_has_perm(current, sock->sk, SOCKET__GETATTR);
3986 }
3987
3988 static int selinux_socket_setsockopt(struct socket *sock, int level, int optname)
3989 {
3990 int err;
3991
3992 err = sock_has_perm(current, sock->sk, SOCKET__SETOPT);
3993 if (err)
3994 return err;
3995
3996 return selinux_netlbl_socket_setsockopt(sock, level, optname);
3997 }
3998
3999 static int selinux_socket_getsockopt(struct socket *sock, int level,
4000 int optname)
4001 {
4002 return sock_has_perm(current, sock->sk, SOCKET__GETOPT);
4003 }
4004
4005 static int selinux_socket_shutdown(struct socket *sock, int how)
4006 {
4007 return sock_has_perm(current, sock->sk, SOCKET__SHUTDOWN);
4008 }
4009
4010 static int selinux_socket_unix_stream_connect(struct sock *sock,
4011 struct sock *other,
4012 struct sock *newsk)
4013 {
4014 struct sk_security_struct *sksec_sock = sock->sk_security;
4015 struct sk_security_struct *sksec_other = other->sk_security;
4016 struct sk_security_struct *sksec_new = newsk->sk_security;
4017 struct common_audit_data ad;
4018 int err;
4019
4020 COMMON_AUDIT_DATA_INIT(&ad, NET);
4021 ad.u.net.sk = other;
4022
4023 err = avc_has_perm(sksec_sock->sid, sksec_other->sid,
4024 sksec_other->sclass,
4025 UNIX_STREAM_SOCKET__CONNECTTO, &ad);
4026 if (err)
4027 return err;
4028
4029 /* server child socket */
4030 sksec_new->peer_sid = sksec_sock->sid;
4031 err = security_sid_mls_copy(sksec_other->sid, sksec_sock->sid,
4032 &sksec_new->sid);
4033 if (err)
4034 return err;
4035
4036 /* connecting socket */
4037 sksec_sock->peer_sid = sksec_new->sid;
4038
4039 return 0;
4040 }
4041
4042 static int selinux_socket_unix_may_send(struct socket *sock,
4043 struct socket *other)
4044 {
4045 struct sk_security_struct *ssec = sock->sk->sk_security;
4046 struct sk_security_struct *osec = other->sk->sk_security;
4047 struct common_audit_data ad;
4048
4049 COMMON_AUDIT_DATA_INIT(&ad, NET);
4050 ad.u.net.sk = other->sk;
4051
4052 return avc_has_perm(ssec->sid, osec->sid, osec->sclass, SOCKET__SENDTO,
4053 &ad);
4054 }
4055
4056 static int selinux_inet_sys_rcv_skb(int ifindex, char *addrp, u16 family,
4057 u32 peer_sid,
4058 struct common_audit_data *ad)
4059 {
4060 int err;
4061 u32 if_sid;
4062 u32 node_sid;
4063
4064 err = sel_netif_sid(ifindex, &if_sid);
4065 if (err)
4066 return err;
4067 err = avc_has_perm(peer_sid, if_sid,
4068 SECCLASS_NETIF, NETIF__INGRESS, ad);
4069 if (err)
4070 return err;
4071
4072 err = sel_netnode_sid(addrp, family, &node_sid);
4073 if (err)
4074 return err;
4075 return avc_has_perm(peer_sid, node_sid,
4076 SECCLASS_NODE, NODE__RECVFROM, ad);
4077 }
4078
4079 static int selinux_sock_rcv_skb_compat(struct sock *sk, struct sk_buff *skb,
4080 u16 family)
4081 {
4082 int err = 0;
4083 struct sk_security_struct *sksec = sk->sk_security;
4084 u32 sk_sid = sksec->sid;
4085 struct common_audit_data ad;
4086 char *addrp;
4087
4088 COMMON_AUDIT_DATA_INIT(&ad, NET);
4089 ad.u.net.netif = skb->skb_iif;
4090 ad.u.net.family = family;
4091 err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL);
4092 if (err)
4093 return err;
4094
4095 if (selinux_secmark_enabled()) {
4096 err = avc_has_perm(sk_sid, skb->secmark, SECCLASS_PACKET,
4097 PACKET__RECV, &ad);
4098 if (err)
4099 return err;
4100 }
4101
4102 err = selinux_netlbl_sock_rcv_skb(sksec, skb, family, &ad);
4103 if (err)
4104 return err;
4105 err = selinux_xfrm_sock_rcv_skb(sksec->sid, skb, &ad);
4106
4107 return err;
4108 }
4109
4110 static int selinux_socket_sock_rcv_skb(struct sock *sk, struct sk_buff *skb)
4111 {
4112 int err;
4113 struct sk_security_struct *sksec = sk->sk_security;
4114 u16 family = sk->sk_family;
4115 u32 sk_sid = sksec->sid;
4116 struct common_audit_data ad;
4117 char *addrp;
4118 u8 secmark_active;
4119 u8 peerlbl_active;
4120
4121 if (family != PF_INET && family != PF_INET6)
4122 return 0;
4123
4124 /* Handle mapped IPv4 packets arriving via IPv6 sockets */
4125 if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
4126 family = PF_INET;
4127
4128 /* If any sort of compatibility mode is enabled then handoff processing
4129 * to the selinux_sock_rcv_skb_compat() function to deal with the
4130 * special handling. We do this in an attempt to keep this function
4131 * as fast and as clean as possible. */
4132 if (!selinux_policycap_netpeer)
4133 return selinux_sock_rcv_skb_compat(sk, skb, family);
4134
4135 secmark_active = selinux_secmark_enabled();
4136 peerlbl_active = netlbl_enabled() || selinux_xfrm_enabled();
4137 if (!secmark_active && !peerlbl_active)
4138 return 0;
4139
4140 COMMON_AUDIT_DATA_INIT(&ad, NET);
4141 ad.u.net.netif = skb->skb_iif;
4142 ad.u.net.family = family;
4143 err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL);
4144 if (err)
4145 return err;
4146
4147 if (peerlbl_active) {
4148 u32 peer_sid;
4149
4150 err = selinux_skb_peerlbl_sid(skb, family, &peer_sid);
4151 if (err)
4152 return err;
4153 err = selinux_inet_sys_rcv_skb(skb->skb_iif, addrp, family,
4154 peer_sid, &ad);
4155 if (err) {
4156 selinux_netlbl_err(skb, err, 0);
4157 return err;
4158 }
4159 err = avc_has_perm(sk_sid, peer_sid, SECCLASS_PEER,
4160 PEER__RECV, &ad);
4161 if (err)
4162 selinux_netlbl_err(skb, err, 0);
4163 }
4164
4165 if (secmark_active) {
4166 err = avc_has_perm(sk_sid, skb->secmark, SECCLASS_PACKET,
4167 PACKET__RECV, &ad);
4168 if (err)
4169 return err;
4170 }
4171
4172 return err;
4173 }
4174
4175 static int selinux_socket_getpeersec_stream(struct socket *sock, char __user *optval,
4176 int __user *optlen, unsigned len)
4177 {
4178 int err = 0;
4179 char *scontext;
4180 u32 scontext_len;
4181 struct sk_security_struct *sksec = sock->sk->sk_security;
4182 u32 peer_sid = SECSID_NULL;
4183
4184 if (sksec->sclass == SECCLASS_UNIX_STREAM_SOCKET ||
4185 sksec->sclass == SECCLASS_TCP_SOCKET)
4186 peer_sid = sksec->peer_sid;
4187 if (peer_sid == SECSID_NULL)
4188 return -ENOPROTOOPT;
4189
4190 err = security_sid_to_context(peer_sid, &scontext, &scontext_len);
4191 if (err)
4192 return err;
4193
4194 if (scontext_len > len) {
4195 err = -ERANGE;
4196 goto out_len;
4197 }
4198
4199 if (copy_to_user(optval, scontext, scontext_len))
4200 err = -EFAULT;
4201
4202 out_len:
4203 if (put_user(scontext_len, optlen))
4204 err = -EFAULT;
4205 kfree(scontext);
4206 return err;
4207 }
4208
4209 static int selinux_socket_getpeersec_dgram(struct socket *sock, struct sk_buff *skb, u32 *secid)
4210 {
4211 u32 peer_secid = SECSID_NULL;
4212 u16 family;
4213
4214 if (skb && skb->protocol == htons(ETH_P_IP))
4215 family = PF_INET;
4216 else if (skb && skb->protocol == htons(ETH_P_IPV6))
4217 family = PF_INET6;
4218 else if (sock)
4219 family = sock->sk->sk_family;
4220 else
4221 goto out;
4222
4223 if (sock && family == PF_UNIX)
4224 selinux_inode_getsecid(SOCK_INODE(sock), &peer_secid);
4225 else if (skb)
4226 selinux_skb_peerlbl_sid(skb, family, &peer_secid);
4227
4228 out:
4229 *secid = peer_secid;
4230 if (peer_secid == SECSID_NULL)
4231 return -EINVAL;
4232 return 0;
4233 }
4234
4235 static int selinux_sk_alloc_security(struct sock *sk, int family, gfp_t priority)
4236 {
4237 struct sk_security_struct *sksec;
4238
4239 sksec = kzalloc(sizeof(*sksec), priority);
4240 if (!sksec)
4241 return -ENOMEM;
4242
4243 sksec->peer_sid = SECINITSID_UNLABELED;
4244 sksec->sid = SECINITSID_UNLABELED;
4245 selinux_netlbl_sk_security_reset(sksec);
4246 sk->sk_security = sksec;
4247
4248 return 0;
4249 }
4250
4251 static void selinux_sk_free_security(struct sock *sk)
4252 {
4253 struct sk_security_struct *sksec = sk->sk_security;
4254
4255 sk->sk_security = NULL;
4256 selinux_netlbl_sk_security_free(sksec);
4257 kfree(sksec);
4258 }
4259
4260 static void selinux_sk_clone_security(const struct sock *sk, struct sock *newsk)
4261 {
4262 struct sk_security_struct *sksec = sk->sk_security;
4263 struct sk_security_struct *newsksec = newsk->sk_security;
4264
4265 newsksec->sid = sksec->sid;
4266 newsksec->peer_sid = sksec->peer_sid;
4267 newsksec->sclass = sksec->sclass;
4268
4269 selinux_netlbl_sk_security_reset(newsksec);
4270 }
4271
4272 static void selinux_sk_getsecid(struct sock *sk, u32 *secid)
4273 {
4274 if (!sk)
4275 *secid = SECINITSID_ANY_SOCKET;
4276 else {
4277 struct sk_security_struct *sksec = sk->sk_security;
4278
4279 *secid = sksec->sid;
4280 }
4281 }
4282
4283 static void selinux_sock_graft(struct sock *sk, struct socket *parent)
4284 {
4285 struct inode_security_struct *isec = SOCK_INODE(parent)->i_security;
4286 struct sk_security_struct *sksec = sk->sk_security;
4287
4288 if (sk->sk_family == PF_INET || sk->sk_family == PF_INET6 ||
4289 sk->sk_family == PF_UNIX)
4290 isec->sid = sksec->sid;
4291 sksec->sclass = isec->sclass;
4292 }
4293
4294 static int selinux_inet_conn_request(struct sock *sk, struct sk_buff *skb,
4295 struct request_sock *req)
4296 {
4297 struct sk_security_struct *sksec = sk->sk_security;
4298 int err;
4299 u16 family = sk->sk_family;
4300 u32 newsid;
4301 u32 peersid;
4302
4303 /* handle mapped IPv4 packets arriving via IPv6 sockets */
4304 if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
4305 family = PF_INET;
4306
4307 err = selinux_skb_peerlbl_sid(skb, family, &peersid);
4308 if (err)
4309 return err;
4310 if (peersid == SECSID_NULL) {
4311 req->secid = sksec->sid;
4312 req->peer_secid = SECSID_NULL;
4313 } else {
4314 err = security_sid_mls_copy(sksec->sid, peersid, &newsid);
4315 if (err)
4316 return err;
4317 req->secid = newsid;
4318 req->peer_secid = peersid;
4319 }
4320
4321 return selinux_netlbl_inet_conn_request(req, family);
4322 }
4323
4324 static void selinux_inet_csk_clone(struct sock *newsk,
4325 const struct request_sock *req)
4326 {
4327 struct sk_security_struct *newsksec = newsk->sk_security;
4328
4329 newsksec->sid = req->secid;
4330 newsksec->peer_sid = req->peer_secid;
4331 /* NOTE: Ideally, we should also get the isec->sid for the
4332 new socket in sync, but we don't have the isec available yet.
4333 So we will wait until sock_graft to do it, by which
4334 time it will have been created and available. */
4335
4336 /* We don't need to take any sort of lock here as we are the only
4337 * thread with access to newsksec */
4338 selinux_netlbl_inet_csk_clone(newsk, req->rsk_ops->family);
4339 }
4340
4341 static void selinux_inet_conn_established(struct sock *sk, struct sk_buff *skb)
4342 {
4343 u16 family = sk->sk_family;
4344 struct sk_security_struct *sksec = sk->sk_security;
4345
4346 /* handle mapped IPv4 packets arriving via IPv6 sockets */
4347 if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
4348 family = PF_INET;
4349
4350 selinux_skb_peerlbl_sid(skb, family, &sksec->peer_sid);
4351 }
4352
4353 static int selinux_secmark_relabel_packet(u32 sid)
4354 {
4355 const struct task_security_struct *__tsec;
4356 u32 tsid;
4357
4358 __tsec = current_security();
4359 tsid = __tsec->sid;
4360
4361 return avc_has_perm(tsid, sid, SECCLASS_PACKET, PACKET__RELABELTO, NULL);
4362 }
4363
4364 static void selinux_secmark_refcount_inc(void)
4365 {
4366 atomic_inc(&selinux_secmark_refcount);
4367 }
4368
4369 static void selinux_secmark_refcount_dec(void)
4370 {
4371 atomic_dec(&selinux_secmark_refcount);
4372 }
4373
4374 static void selinux_req_classify_flow(const struct request_sock *req,
4375 struct flowi *fl)
4376 {
4377 fl->flowi_secid = req->secid;
4378 }
4379
4380 static int selinux_tun_dev_create(void)
4381 {
4382 u32 sid = current_sid();
4383
4384 /* we aren't taking into account the "sockcreate" SID since the socket
4385 * that is being created here is not a socket in the traditional sense,
4386 * instead it is a private sock, accessible only to the kernel, and
4387 * representing a wide range of network traffic spanning multiple
4388 * connections unlike traditional sockets - check the TUN driver to
4389 * get a better understanding of why this socket is special */
4390
4391 return avc_has_perm(sid, sid, SECCLASS_TUN_SOCKET, TUN_SOCKET__CREATE,
4392 NULL);
4393 }
4394
4395 static void selinux_tun_dev_post_create(struct sock *sk)
4396 {
4397 struct sk_security_struct *sksec = sk->sk_security;
4398
4399 /* we don't currently perform any NetLabel based labeling here and it
4400 * isn't clear that we would want to do so anyway; while we could apply
4401 * labeling without the support of the TUN user the resulting labeled
4402 * traffic from the other end of the connection would almost certainly
4403 * cause confusion to the TUN user that had no idea network labeling
4404 * protocols were being used */
4405
4406 /* see the comments in selinux_tun_dev_create() about why we don't use
4407 * the sockcreate SID here */
4408
4409 sksec->sid = current_sid();
4410 sksec->sclass = SECCLASS_TUN_SOCKET;
4411 }
4412
4413 static int selinux_tun_dev_attach(struct sock *sk)
4414 {
4415 struct sk_security_struct *sksec = sk->sk_security;
4416 u32 sid = current_sid();
4417 int err;
4418
4419 err = avc_has_perm(sid, sksec->sid, SECCLASS_TUN_SOCKET,
4420 TUN_SOCKET__RELABELFROM, NULL);
4421 if (err)
4422 return err;
4423 err = avc_has_perm(sid, sid, SECCLASS_TUN_SOCKET,
4424 TUN_SOCKET__RELABELTO, NULL);
4425 if (err)
4426 return err;
4427
4428 sksec->sid = sid;
4429
4430 return 0;
4431 }
4432
4433 static int selinux_nlmsg_perm(struct sock *sk, struct sk_buff *skb)
4434 {
4435 int err = 0;
4436 u32 perm;
4437 struct nlmsghdr *nlh;
4438 struct sk_security_struct *sksec = sk->sk_security;
4439
4440 if (skb->len < NLMSG_SPACE(0)) {
4441 err = -EINVAL;
4442 goto out;
4443 }
4444 nlh = nlmsg_hdr(skb);
4445
4446 err = selinux_nlmsg_lookup(sksec->sclass, nlh->nlmsg_type, &perm);
4447 if (err) {
4448 if (err == -EINVAL) {
4449 audit_log(current->audit_context, GFP_KERNEL, AUDIT_SELINUX_ERR,
4450 "SELinux: unrecognized netlink message"
4451 " type=%hu for sclass=%hu\n",
4452 nlh->nlmsg_type, sksec->sclass);
4453 if (!selinux_enforcing || security_get_allow_unknown())
4454 err = 0;
4455 }
4456
4457 /* Ignore */
4458 if (err == -ENOENT)
4459 err = 0;
4460 goto out;
4461 }
4462
4463 err = sock_has_perm(current, sk, perm);
4464 out:
4465 return err;
4466 }
4467
4468 #ifdef CONFIG_NETFILTER
4469
4470 static unsigned int selinux_ip_forward(struct sk_buff *skb, int ifindex,
4471 u16 family)
4472 {
4473 int err;
4474 char *addrp;
4475 u32 peer_sid;
4476 struct common_audit_data ad;
4477 u8 secmark_active;
4478 u8 netlbl_active;
4479 u8 peerlbl_active;
4480
4481 if (!selinux_policycap_netpeer)
4482 return NF_ACCEPT;
4483
4484 secmark_active = selinux_secmark_enabled();
4485 netlbl_active = netlbl_enabled();
4486 peerlbl_active = netlbl_active || selinux_xfrm_enabled();
4487 if (!secmark_active && !peerlbl_active)
4488 return NF_ACCEPT;
4489
4490 if (selinux_skb_peerlbl_sid(skb, family, &peer_sid) != 0)
4491 return NF_DROP;
4492
4493 COMMON_AUDIT_DATA_INIT(&ad, NET);
4494 ad.u.net.netif = ifindex;
4495 ad.u.net.family = family;
4496 if (selinux_parse_skb(skb, &ad, &addrp, 1, NULL) != 0)
4497 return NF_DROP;
4498
4499 if (peerlbl_active) {
4500 err = selinux_inet_sys_rcv_skb(ifindex, addrp, family,
4501 peer_sid, &ad);
4502 if (err) {
4503 selinux_netlbl_err(skb, err, 1);
4504 return NF_DROP;
4505 }
4506 }
4507
4508 if (secmark_active)
4509 if (avc_has_perm(peer_sid, skb->secmark,
4510 SECCLASS_PACKET, PACKET__FORWARD_IN, &ad))
4511 return NF_DROP;
4512
4513 if (netlbl_active)
4514 /* we do this in the FORWARD path and not the POST_ROUTING
4515 * path because we want to make sure we apply the necessary
4516 * labeling before IPsec is applied so we can leverage AH
4517 * protection */
4518 if (selinux_netlbl_skbuff_setsid(skb, family, peer_sid) != 0)
4519 return NF_DROP;
4520
4521 return NF_ACCEPT;
4522 }
4523
4524 static unsigned int selinux_ipv4_forward(unsigned int hooknum,
4525 struct sk_buff *skb,
4526 const struct net_device *in,
4527 const struct net_device *out,
4528 int (*okfn)(struct sk_buff *))
4529 {
4530 return selinux_ip_forward(skb, in->ifindex, PF_INET);
4531 }
4532
4533 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
4534 static unsigned int selinux_ipv6_forward(unsigned int hooknum,
4535 struct sk_buff *skb,
4536 const struct net_device *in,
4537 const struct net_device *out,
4538 int (*okfn)(struct sk_buff *))
4539 {
4540 return selinux_ip_forward(skb, in->ifindex, PF_INET6);
4541 }
4542 #endif /* IPV6 */
4543
4544 static unsigned int selinux_ip_output(struct sk_buff *skb,
4545 u16 family)
4546 {
4547 u32 sid;
4548
4549 if (!netlbl_enabled())
4550 return NF_ACCEPT;
4551
4552 /* we do this in the LOCAL_OUT path and not the POST_ROUTING path
4553 * because we want to make sure we apply the necessary labeling
4554 * before IPsec is applied so we can leverage AH protection */
4555 if (skb->sk) {
4556 struct sk_security_struct *sksec = skb->sk->sk_security;
4557 sid = sksec->sid;
4558 } else
4559 sid = SECINITSID_KERNEL;
4560 if (selinux_netlbl_skbuff_setsid(skb, family, sid) != 0)
4561 return NF_DROP;
4562
4563 return NF_ACCEPT;
4564 }
4565
4566 static unsigned int selinux_ipv4_output(unsigned int hooknum,
4567 struct sk_buff *skb,
4568 const struct net_device *in,
4569 const struct net_device *out,
4570 int (*okfn)(struct sk_buff *))
4571 {
4572 return selinux_ip_output(skb, PF_INET);
4573 }
4574
4575 static unsigned int selinux_ip_postroute_compat(struct sk_buff *skb,
4576 int ifindex,
4577 u16 family)
4578 {
4579 struct sock *sk = skb->sk;
4580 struct sk_security_struct *sksec;
4581 struct common_audit_data ad;
4582 char *addrp;
4583 u8 proto;
4584
4585 if (sk == NULL)
4586 return NF_ACCEPT;
4587 sksec = sk->sk_security;
4588
4589 COMMON_AUDIT_DATA_INIT(&ad, NET);
4590 ad.u.net.netif = ifindex;
4591 ad.u.net.family = family;
4592 if (selinux_parse_skb(skb, &ad, &addrp, 0, &proto))
4593 return NF_DROP;
4594
4595 if (selinux_secmark_enabled())
4596 if (avc_has_perm(sksec->sid, skb->secmark,
4597 SECCLASS_PACKET, PACKET__SEND, &ad))
4598 return NF_DROP_ERR(-ECONNREFUSED);
4599
4600 if (selinux_xfrm_postroute_last(sksec->sid, skb, &ad, proto))
4601 return NF_DROP_ERR(-ECONNREFUSED);
4602
4603 return NF_ACCEPT;
4604 }
4605
4606 static unsigned int selinux_ip_postroute(struct sk_buff *skb, int ifindex,
4607 u16 family)
4608 {
4609 u32 secmark_perm;
4610 u32 peer_sid;
4611 struct sock *sk;
4612 struct common_audit_data ad;
4613 char *addrp;
4614 u8 secmark_active;
4615 u8 peerlbl_active;
4616
4617 /* If any sort of compatibility mode is enabled then handoff processing
4618 * to the selinux_ip_postroute_compat() function to deal with the
4619 * special handling. We do this in an attempt to keep this function
4620 * as fast and as clean as possible. */
4621 if (!selinux_policycap_netpeer)
4622 return selinux_ip_postroute_compat(skb, ifindex, family);
4623 #ifdef CONFIG_XFRM
4624 /* If skb->dst->xfrm is non-NULL then the packet is undergoing an IPsec
4625 * packet transformation so allow the packet to pass without any checks
4626 * since we'll have another chance to perform access control checks
4627 * when the packet is on it's final way out.
4628 * NOTE: there appear to be some IPv6 multicast cases where skb->dst
4629 * is NULL, in this case go ahead and apply access control. */
4630 if (skb_dst(skb) != NULL && skb_dst(skb)->xfrm != NULL)
4631 return NF_ACCEPT;
4632 #endif
4633 secmark_active = selinux_secmark_enabled();
4634 peerlbl_active = netlbl_enabled() || selinux_xfrm_enabled();
4635 if (!secmark_active && !peerlbl_active)
4636 return NF_ACCEPT;
4637
4638 /* if the packet is being forwarded then get the peer label from the
4639 * packet itself; otherwise check to see if it is from a local
4640 * application or the kernel, if from an application get the peer label
4641 * from the sending socket, otherwise use the kernel's sid */
4642 sk = skb->sk;
4643 if (sk == NULL) {
4644 if (skb->skb_iif) {
4645 secmark_perm = PACKET__FORWARD_OUT;
4646 if (selinux_skb_peerlbl_sid(skb, family, &peer_sid))
4647 return NF_DROP;
4648 } else {
4649 secmark_perm = PACKET__SEND;
4650 peer_sid = SECINITSID_KERNEL;
4651 }
4652 } else {
4653 struct sk_security_struct *sksec = sk->sk_security;
4654 peer_sid = sksec->sid;
4655 secmark_perm = PACKET__SEND;
4656 }
4657
4658 COMMON_AUDIT_DATA_INIT(&ad, NET);
4659 ad.u.net.netif = ifindex;
4660 ad.u.net.family = family;
4661 if (selinux_parse_skb(skb, &ad, &addrp, 0, NULL))
4662 return NF_DROP;
4663
4664 if (secmark_active)
4665 if (avc_has_perm(peer_sid, skb->secmark,
4666 SECCLASS_PACKET, secmark_perm, &ad))
4667 return NF_DROP_ERR(-ECONNREFUSED);
4668
4669 if (peerlbl_active) {
4670 u32 if_sid;
4671 u32 node_sid;
4672
4673 if (sel_netif_sid(ifindex, &if_sid))
4674 return NF_DROP;
4675 if (avc_has_perm(peer_sid, if_sid,
4676 SECCLASS_NETIF, NETIF__EGRESS, &ad))
4677 return NF_DROP_ERR(-ECONNREFUSED);
4678
4679 if (sel_netnode_sid(addrp, family, &node_sid))
4680 return NF_DROP;
4681 if (avc_has_perm(peer_sid, node_sid,
4682 SECCLASS_NODE, NODE__SENDTO, &ad))
4683 return NF_DROP_ERR(-ECONNREFUSED);
4684 }
4685
4686 return NF_ACCEPT;
4687 }
4688
4689 static unsigned int selinux_ipv4_postroute(unsigned int hooknum,
4690 struct sk_buff *skb,
4691 const struct net_device *in,
4692 const struct net_device *out,
4693 int (*okfn)(struct sk_buff *))
4694 {
4695 return selinux_ip_postroute(skb, out->ifindex, PF_INET);
4696 }
4697
4698 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
4699 static unsigned int selinux_ipv6_postroute(unsigned int hooknum,
4700 struct sk_buff *skb,
4701 const struct net_device *in,
4702 const struct net_device *out,
4703 int (*okfn)(struct sk_buff *))
4704 {
4705 return selinux_ip_postroute(skb, out->ifindex, PF_INET6);
4706 }
4707 #endif /* IPV6 */
4708
4709 #endif /* CONFIG_NETFILTER */
4710
4711 static int selinux_netlink_send(struct sock *sk, struct sk_buff *skb)
4712 {
4713 int err;
4714
4715 err = cap_netlink_send(sk, skb);
4716 if (err)
4717 return err;
4718
4719 return selinux_nlmsg_perm(sk, skb);
4720 }
4721
4722 static int selinux_netlink_recv(struct sk_buff *skb, int capability)
4723 {
4724 int err;
4725 struct common_audit_data ad;
4726 u32 sid;
4727
4728 err = cap_netlink_recv(skb, capability);
4729 if (err)
4730 return err;
4731
4732 COMMON_AUDIT_DATA_INIT(&ad, CAP);
4733 ad.u.cap = capability;
4734
4735 security_task_getsecid(current, &sid);
4736 return avc_has_perm(sid, sid, SECCLASS_CAPABILITY,
4737 CAP_TO_MASK(capability), &ad);
4738 }
4739
4740 static int ipc_alloc_security(struct task_struct *task,
4741 struct kern_ipc_perm *perm,
4742 u16 sclass)
4743 {
4744 struct ipc_security_struct *isec;
4745 u32 sid;
4746
4747 isec = kzalloc(sizeof(struct ipc_security_struct), GFP_KERNEL);
4748 if (!isec)
4749 return -ENOMEM;
4750
4751 sid = task_sid(task);
4752 isec->sclass = sclass;
4753 isec->sid = sid;
4754 perm->security = isec;
4755
4756 return 0;
4757 }
4758
4759 static void ipc_free_security(struct kern_ipc_perm *perm)
4760 {
4761 struct ipc_security_struct *isec = perm->security;
4762 perm->security = NULL;
4763 kfree(isec);
4764 }
4765
4766 static int msg_msg_alloc_security(struct msg_msg *msg)
4767 {
4768 struct msg_security_struct *msec;
4769
4770 msec = kzalloc(sizeof(struct msg_security_struct), GFP_KERNEL);
4771 if (!msec)
4772 return -ENOMEM;
4773
4774 msec->sid = SECINITSID_UNLABELED;
4775 msg->security = msec;
4776
4777 return 0;
4778 }
4779
4780 static void msg_msg_free_security(struct msg_msg *msg)
4781 {
4782 struct msg_security_struct *msec = msg->security;
4783
4784 msg->security = NULL;
4785 kfree(msec);
4786 }
4787
4788 static int ipc_has_perm(struct kern_ipc_perm *ipc_perms,
4789 u32 perms)
4790 {
4791 struct ipc_security_struct *isec;
4792 struct common_audit_data ad;
4793 u32 sid = current_sid();
4794
4795 isec = ipc_perms->security;
4796
4797 COMMON_AUDIT_DATA_INIT(&ad, IPC);
4798 ad.u.ipc_id = ipc_perms->key;
4799
4800 return avc_has_perm(sid, isec->sid, isec->sclass, perms, &ad);
4801 }
4802
4803 static int selinux_msg_msg_alloc_security(struct msg_msg *msg)
4804 {
4805 return msg_msg_alloc_security(msg);
4806 }
4807
4808 static void selinux_msg_msg_free_security(struct msg_msg *msg)
4809 {
4810 msg_msg_free_security(msg);
4811 }
4812
4813 /* message queue security operations */
4814 static int selinux_msg_queue_alloc_security(struct msg_queue *msq)
4815 {
4816 struct ipc_security_struct *isec;
4817 struct common_audit_data ad;
4818 u32 sid = current_sid();
4819 int rc;
4820
4821 rc = ipc_alloc_security(current, &msq->q_perm, SECCLASS_MSGQ);
4822 if (rc)
4823 return rc;
4824
4825 isec = msq->q_perm.security;
4826
4827 COMMON_AUDIT_DATA_INIT(&ad, IPC);
4828 ad.u.ipc_id = msq->q_perm.key;
4829
4830 rc = avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
4831 MSGQ__CREATE, &ad);
4832 if (rc) {
4833 ipc_free_security(&msq->q_perm);
4834 return rc;
4835 }
4836 return 0;
4837 }
4838
4839 static void selinux_msg_queue_free_security(struct msg_queue *msq)
4840 {
4841 ipc_free_security(&msq->q_perm);
4842 }
4843
4844 static int selinux_msg_queue_associate(struct msg_queue *msq, int msqflg)
4845 {
4846 struct ipc_security_struct *isec;
4847 struct common_audit_data ad;
4848 u32 sid = current_sid();
4849
4850 isec = msq->q_perm.security;
4851
4852 COMMON_AUDIT_DATA_INIT(&ad, IPC);
4853 ad.u.ipc_id = msq->q_perm.key;
4854
4855 return avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
4856 MSGQ__ASSOCIATE, &ad);
4857 }
4858
4859 static int selinux_msg_queue_msgctl(struct msg_queue *msq, int cmd)
4860 {
4861 int err;
4862 int perms;
4863
4864 switch (cmd) {
4865 case IPC_INFO:
4866 case MSG_INFO:
4867 /* No specific object, just general system-wide information. */
4868 return task_has_system(current, SYSTEM__IPC_INFO);
4869 case IPC_STAT:
4870 case MSG_STAT:
4871 perms = MSGQ__GETATTR | MSGQ__ASSOCIATE;
4872 break;
4873 case IPC_SET:
4874 perms = MSGQ__SETATTR;
4875 break;
4876 case IPC_RMID:
4877 perms = MSGQ__DESTROY;
4878 break;
4879 default:
4880 return 0;
4881 }
4882
4883 err = ipc_has_perm(&msq->q_perm, perms);
4884 return err;
4885 }
4886
4887 static int selinux_msg_queue_msgsnd(struct msg_queue *msq, struct msg_msg *msg, int msqflg)
4888 {
4889 struct ipc_security_struct *isec;
4890 struct msg_security_struct *msec;
4891 struct common_audit_data ad;
4892 u32 sid = current_sid();
4893 int rc;
4894
4895 isec = msq->q_perm.security;
4896 msec = msg->security;
4897
4898 /*
4899 * First time through, need to assign label to the message
4900 */
4901 if (msec->sid == SECINITSID_UNLABELED) {
4902 /*
4903 * Compute new sid based on current process and
4904 * message queue this message will be stored in
4905 */
4906 rc = security_transition_sid(sid, isec->sid, SECCLASS_MSG,
4907 NULL, &msec->sid);
4908 if (rc)
4909 return rc;
4910 }
4911
4912 COMMON_AUDIT_DATA_INIT(&ad, IPC);
4913 ad.u.ipc_id = msq->q_perm.key;
4914
4915 /* Can this process write to the queue? */
4916 rc = avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
4917 MSGQ__WRITE, &ad);
4918 if (!rc)
4919 /* Can this process send the message */
4920 rc = avc_has_perm(sid, msec->sid, SECCLASS_MSG,
4921 MSG__SEND, &ad);
4922 if (!rc)
4923 /* Can the message be put in the queue? */
4924 rc = avc_has_perm(msec->sid, isec->sid, SECCLASS_MSGQ,
4925 MSGQ__ENQUEUE, &ad);
4926
4927 return rc;
4928 }
4929
4930 static int selinux_msg_queue_msgrcv(struct msg_queue *msq, struct msg_msg *msg,
4931 struct task_struct *target,
4932 long type, int mode)
4933 {
4934 struct ipc_security_struct *isec;
4935 struct msg_security_struct *msec;
4936 struct common_audit_data ad;
4937 u32 sid = task_sid(target);
4938 int rc;
4939
4940 isec = msq->q_perm.security;
4941 msec = msg->security;
4942
4943 COMMON_AUDIT_DATA_INIT(&ad, IPC);
4944 ad.u.ipc_id = msq->q_perm.key;
4945
4946 rc = avc_has_perm(sid, isec->sid,
4947 SECCLASS_MSGQ, MSGQ__READ, &ad);
4948 if (!rc)
4949 rc = avc_has_perm(sid, msec->sid,
4950 SECCLASS_MSG, MSG__RECEIVE, &ad);
4951 return rc;
4952 }
4953
4954 /* Shared Memory security operations */
4955 static int selinux_shm_alloc_security(struct shmid_kernel *shp)
4956 {
4957 struct ipc_security_struct *isec;
4958 struct common_audit_data ad;
4959 u32 sid = current_sid();
4960 int rc;
4961
4962 rc = ipc_alloc_security(current, &shp->shm_perm, SECCLASS_SHM);
4963 if (rc)
4964 return rc;
4965
4966 isec = shp->shm_perm.security;
4967
4968 COMMON_AUDIT_DATA_INIT(&ad, IPC);
4969 ad.u.ipc_id = shp->shm_perm.key;
4970
4971 rc = avc_has_perm(sid, isec->sid, SECCLASS_SHM,
4972 SHM__CREATE, &ad);
4973 if (rc) {
4974 ipc_free_security(&shp->shm_perm);
4975 return rc;
4976 }
4977 return 0;
4978 }
4979
4980 static void selinux_shm_free_security(struct shmid_kernel *shp)
4981 {
4982 ipc_free_security(&shp->shm_perm);
4983 }
4984
4985 static int selinux_shm_associate(struct shmid_kernel *shp, int shmflg)
4986 {
4987 struct ipc_security_struct *isec;
4988 struct common_audit_data ad;
4989 u32 sid = current_sid();
4990
4991 isec = shp->shm_perm.security;
4992
4993 COMMON_AUDIT_DATA_INIT(&ad, IPC);
4994 ad.u.ipc_id = shp->shm_perm.key;
4995
4996 return avc_has_perm(sid, isec->sid, SECCLASS_SHM,
4997 SHM__ASSOCIATE, &ad);
4998 }
4999
5000 /* Note, at this point, shp is locked down */
5001 static int selinux_shm_shmctl(struct shmid_kernel *shp, int cmd)
5002 {
5003 int perms;
5004 int err;
5005
5006 switch (cmd) {
5007 case IPC_INFO:
5008 case SHM_INFO:
5009 /* No specific object, just general system-wide information. */
5010 return task_has_system(current, SYSTEM__IPC_INFO);
5011 case IPC_STAT:
5012 case SHM_STAT:
5013 perms = SHM__GETATTR | SHM__ASSOCIATE;
5014 break;
5015 case IPC_SET:
5016 perms = SHM__SETATTR;
5017 break;
5018 case SHM_LOCK:
5019 case SHM_UNLOCK:
5020 perms = SHM__LOCK;
5021 break;
5022 case IPC_RMID:
5023 perms = SHM__DESTROY;
5024 break;
5025 default:
5026 return 0;
5027 }
5028
5029 err = ipc_has_perm(&shp->shm_perm, perms);
5030 return err;
5031 }
5032
5033 static int selinux_shm_shmat(struct shmid_kernel *shp,
5034 char __user *shmaddr, int shmflg)
5035 {
5036 u32 perms;
5037
5038 if (shmflg & SHM_RDONLY)
5039 perms = SHM__READ;
5040 else
5041 perms = SHM__READ | SHM__WRITE;
5042
5043 return ipc_has_perm(&shp->shm_perm, perms);
5044 }
5045
5046 /* Semaphore security operations */
5047 static int selinux_sem_alloc_security(struct sem_array *sma)
5048 {
5049 struct ipc_security_struct *isec;
5050 struct common_audit_data ad;
5051 u32 sid = current_sid();
5052 int rc;
5053
5054 rc = ipc_alloc_security(current, &sma->sem_perm, SECCLASS_SEM);
5055 if (rc)
5056 return rc;
5057
5058 isec = sma->sem_perm.security;
5059
5060 COMMON_AUDIT_DATA_INIT(&ad, IPC);
5061 ad.u.ipc_id = sma->sem_perm.key;
5062
5063 rc = avc_has_perm(sid, isec->sid, SECCLASS_SEM,
5064 SEM__CREATE, &ad);
5065 if (rc) {
5066 ipc_free_security(&sma->sem_perm);
5067 return rc;
5068 }
5069 return 0;
5070 }
5071
5072 static void selinux_sem_free_security(struct sem_array *sma)
5073 {
5074 ipc_free_security(&sma->sem_perm);
5075 }
5076
5077 static int selinux_sem_associate(struct sem_array *sma, int semflg)
5078 {
5079 struct ipc_security_struct *isec;
5080 struct common_audit_data ad;
5081 u32 sid = current_sid();
5082
5083 isec = sma->sem_perm.security;
5084
5085 COMMON_AUDIT_DATA_INIT(&ad, IPC);
5086 ad.u.ipc_id = sma->sem_perm.key;
5087
5088 return avc_has_perm(sid, isec->sid, SECCLASS_SEM,
5089 SEM__ASSOCIATE, &ad);
5090 }
5091
5092 /* Note, at this point, sma is locked down */
5093 static int selinux_sem_semctl(struct sem_array *sma, int cmd)
5094 {
5095 int err;
5096 u32 perms;
5097
5098 switch (cmd) {
5099 case IPC_INFO:
5100 case SEM_INFO:
5101 /* No specific object, just general system-wide information. */
5102 return task_has_system(current, SYSTEM__IPC_INFO);
5103 case GETPID:
5104 case GETNCNT:
5105 case GETZCNT:
5106 perms = SEM__GETATTR;
5107 break;
5108 case GETVAL:
5109 case GETALL:
5110 perms = SEM__READ;
5111 break;
5112 case SETVAL:
5113 case SETALL:
5114 perms = SEM__WRITE;
5115 break;
5116 case IPC_RMID:
5117 perms = SEM__DESTROY;
5118 break;
5119 case IPC_SET:
5120 perms = SEM__SETATTR;
5121 break;
5122 case IPC_STAT:
5123 case SEM_STAT:
5124 perms = SEM__GETATTR | SEM__ASSOCIATE;
5125 break;
5126 default:
5127 return 0;
5128 }
5129
5130 err = ipc_has_perm(&sma->sem_perm, perms);
5131 return err;
5132 }
5133
5134 static int selinux_sem_semop(struct sem_array *sma,
5135 struct sembuf *sops, unsigned nsops, int alter)
5136 {
5137 u32 perms;
5138
5139 if (alter)
5140 perms = SEM__READ | SEM__WRITE;
5141 else
5142 perms = SEM__READ;
5143
5144 return ipc_has_perm(&sma->sem_perm, perms);
5145 }
5146
5147 static int selinux_ipc_permission(struct kern_ipc_perm *ipcp, short flag)
5148 {
5149 u32 av = 0;
5150
5151 av = 0;
5152 if (flag & S_IRUGO)
5153 av |= IPC__UNIX_READ;
5154 if (flag & S_IWUGO)
5155 av |= IPC__UNIX_WRITE;
5156
5157 if (av == 0)
5158 return 0;
5159
5160 return ipc_has_perm(ipcp, av);
5161 }
5162
5163 static void selinux_ipc_getsecid(struct kern_ipc_perm *ipcp, u32 *secid)
5164 {
5165 struct ipc_security_struct *isec = ipcp->security;
5166 *secid = isec->sid;
5167 }
5168
5169 static void selinux_d_instantiate(struct dentry *dentry, struct inode *inode)
5170 {
5171 if (inode)
5172 inode_doinit_with_dentry(inode, dentry);
5173 }
5174
5175 static int selinux_getprocattr(struct task_struct *p,
5176 char *name, char **value)
5177 {
5178 const struct task_security_struct *__tsec;
5179 u32 sid;
5180 int error;
5181 unsigned len;
5182
5183 if (current != p) {
5184 error = current_has_perm(p, PROCESS__GETATTR);
5185 if (error)
5186 return error;
5187 }
5188
5189 rcu_read_lock();
5190 __tsec = __task_cred(p)->security;
5191
5192 if (!strcmp(name, "current"))
5193 sid = __tsec->sid;
5194 else if (!strcmp(name, "prev"))
5195 sid = __tsec->osid;
5196 else if (!strcmp(name, "exec"))
5197 sid = __tsec->exec_sid;
5198 else if (!strcmp(name, "fscreate"))
5199 sid = __tsec->create_sid;
5200 else if (!strcmp(name, "keycreate"))
5201 sid = __tsec->keycreate_sid;
5202 else if (!strcmp(name, "sockcreate"))
5203 sid = __tsec->sockcreate_sid;
5204 else
5205 goto invalid;
5206 rcu_read_unlock();
5207
5208 if (!sid)
5209 return 0;
5210
5211 error = security_sid_to_context(sid, value, &len);
5212 if (error)
5213 return error;
5214 return len;
5215
5216 invalid:
5217 rcu_read_unlock();
5218 return -EINVAL;
5219 }
5220
5221 static int selinux_setprocattr(struct task_struct *p,
5222 char *name, void *value, size_t size)
5223 {
5224 struct task_security_struct *tsec;
5225 struct task_struct *tracer;
5226 struct cred *new;
5227 u32 sid = 0, ptsid;
5228 int error;
5229 char *str = value;
5230
5231 if (current != p) {
5232 /* SELinux only allows a process to change its own
5233 security attributes. */
5234 return -EACCES;
5235 }
5236
5237 /*
5238 * Basic control over ability to set these attributes at all.
5239 * current == p, but we'll pass them separately in case the
5240 * above restriction is ever removed.
5241 */
5242 if (!strcmp(name, "exec"))
5243 error = current_has_perm(p, PROCESS__SETEXEC);
5244 else if (!strcmp(name, "fscreate"))
5245 error = current_has_perm(p, PROCESS__SETFSCREATE);
5246 else if (!strcmp(name, "keycreate"))
5247 error = current_has_perm(p, PROCESS__SETKEYCREATE);
5248 else if (!strcmp(name, "sockcreate"))
5249 error = current_has_perm(p, PROCESS__SETSOCKCREATE);
5250 else if (!strcmp(name, "current"))
5251 error = current_has_perm(p, PROCESS__SETCURRENT);
5252 else
5253 error = -EINVAL;
5254 if (error)
5255 return error;
5256
5257 /* Obtain a SID for the context, if one was specified. */
5258 if (size && str[1] && str[1] != '\n') {
5259 if (str[size-1] == '\n') {
5260 str[size-1] = 0;
5261 size--;
5262 }
5263 error = security_context_to_sid(value, size, &sid);
5264 if (error == -EINVAL && !strcmp(name, "fscreate")) {
5265 if (!capable(CAP_MAC_ADMIN))
5266 return error;
5267 error = security_context_to_sid_force(value, size,
5268 &sid);
5269 }
5270 if (error)
5271 return error;
5272 }
5273
5274 new = prepare_creds();
5275 if (!new)
5276 return -ENOMEM;
5277
5278 /* Permission checking based on the specified context is
5279 performed during the actual operation (execve,
5280 open/mkdir/...), when we know the full context of the
5281 operation. See selinux_bprm_set_creds for the execve
5282 checks and may_create for the file creation checks. The
5283 operation will then fail if the context is not permitted. */
5284 tsec = new->security;
5285 if (!strcmp(name, "exec")) {
5286 tsec->exec_sid = sid;
5287 } else if (!strcmp(name, "fscreate")) {
5288 tsec->create_sid = sid;
5289 } else if (!strcmp(name, "keycreate")) {
5290 error = may_create_key(sid, p);
5291 if (error)
5292 goto abort_change;
5293 tsec->keycreate_sid = sid;
5294 } else if (!strcmp(name, "sockcreate")) {
5295 tsec->sockcreate_sid = sid;
5296 } else if (!strcmp(name, "current")) {
5297 error = -EINVAL;
5298 if (sid == 0)
5299 goto abort_change;
5300
5301 /* Only allow single threaded processes to change context */
5302 error = -EPERM;
5303 if (!current_is_single_threaded()) {
5304 error = security_bounded_transition(tsec->sid, sid);
5305 if (error)
5306 goto abort_change;
5307 }
5308
5309 /* Check permissions for the transition. */
5310 error = avc_has_perm(tsec->sid, sid, SECCLASS_PROCESS,
5311 PROCESS__DYNTRANSITION, NULL);
5312 if (error)
5313 goto abort_change;
5314
5315 /* Check for ptracing, and update the task SID if ok.
5316 Otherwise, leave SID unchanged and fail. */
5317 ptsid = 0;
5318 task_lock(p);
5319 tracer = ptrace_parent(p);
5320 if (tracer)
5321 ptsid = task_sid(tracer);
5322 task_unlock(p);
5323
5324 if (tracer) {
5325 error = avc_has_perm(ptsid, sid, SECCLASS_PROCESS,
5326 PROCESS__PTRACE, NULL);
5327 if (error)
5328 goto abort_change;
5329 }
5330
5331 tsec->sid = sid;
5332 } else {
5333 error = -EINVAL;
5334 goto abort_change;
5335 }
5336
5337 commit_creds(new);
5338 return size;
5339
5340 abort_change:
5341 abort_creds(new);
5342 return error;
5343 }
5344
5345 static int selinux_secid_to_secctx(u32 secid, char **secdata, u32 *seclen)
5346 {
5347 return security_sid_to_context(secid, secdata, seclen);
5348 }
5349
5350 static int selinux_secctx_to_secid(const char *secdata, u32 seclen, u32 *secid)
5351 {
5352 return security_context_to_sid(secdata, seclen, secid);
5353 }
5354
5355 static void selinux_release_secctx(char *secdata, u32 seclen)
5356 {
5357 kfree(secdata);
5358 }
5359
5360 /*
5361 * called with inode->i_mutex locked
5362 */
5363 static int selinux_inode_notifysecctx(struct inode *inode, void *ctx, u32 ctxlen)
5364 {
5365 return selinux_inode_setsecurity(inode, XATTR_SELINUX_SUFFIX, ctx, ctxlen, 0);
5366 }
5367
5368 /*
5369 * called with inode->i_mutex locked
5370 */
5371 static int selinux_inode_setsecctx(struct dentry *dentry, void *ctx, u32 ctxlen)
5372 {
5373 return __vfs_setxattr_noperm(dentry, XATTR_NAME_SELINUX, ctx, ctxlen, 0);
5374 }
5375
5376 static int selinux_inode_getsecctx(struct inode *inode, void **ctx, u32 *ctxlen)
5377 {
5378 int len = 0;
5379 len = selinux_inode_getsecurity(inode, XATTR_SELINUX_SUFFIX,
5380 ctx, true);
5381 if (len < 0)
5382 return len;
5383 *ctxlen = len;
5384 return 0;
5385 }
5386 #ifdef CONFIG_KEYS
5387
5388 static int selinux_key_alloc(struct key *k, const struct cred *cred,
5389 unsigned long flags)
5390 {
5391 const struct task_security_struct *tsec;
5392 struct key_security_struct *ksec;
5393
5394 ksec = kzalloc(sizeof(struct key_security_struct), GFP_KERNEL);
5395 if (!ksec)
5396 return -ENOMEM;
5397
5398 tsec = cred->security;
5399 if (tsec->keycreate_sid)
5400 ksec->sid = tsec->keycreate_sid;
5401 else
5402 ksec->sid = tsec->sid;
5403
5404 k->security = ksec;
5405 return 0;
5406 }
5407
5408 static void selinux_key_free(struct key *k)
5409 {
5410 struct key_security_struct *ksec = k->security;
5411
5412 k->security = NULL;
5413 kfree(ksec);
5414 }
5415
5416 static int selinux_key_permission(key_ref_t key_ref,
5417 const struct cred *cred,
5418 key_perm_t perm)
5419 {
5420 struct key *key;
5421 struct key_security_struct *ksec;
5422 u32 sid;
5423
5424 /* if no specific permissions are requested, we skip the
5425 permission check. No serious, additional covert channels
5426 appear to be created. */
5427 if (perm == 0)
5428 return 0;
5429
5430 sid = cred_sid(cred);
5431
5432 key = key_ref_to_ptr(key_ref);
5433 ksec = key->security;
5434
5435 return avc_has_perm(sid, ksec->sid, SECCLASS_KEY, perm, NULL);
5436 }
5437
5438 static int selinux_key_getsecurity(struct key *key, char **_buffer)
5439 {
5440 struct key_security_struct *ksec = key->security;
5441 char *context = NULL;
5442 unsigned len;
5443 int rc;
5444
5445 rc = security_sid_to_context(ksec->sid, &context, &len);
5446 if (!rc)
5447 rc = len;
5448 *_buffer = context;
5449 return rc;
5450 }
5451
5452 #endif
5453
5454 static struct security_operations selinux_ops = {
5455 .name = "selinux",
5456
5457 .ptrace_access_check = selinux_ptrace_access_check,
5458 .ptrace_traceme = selinux_ptrace_traceme,
5459 .capget = selinux_capget,
5460 .capset = selinux_capset,
5461 .capable = selinux_capable,
5462 .quotactl = selinux_quotactl,
5463 .quota_on = selinux_quota_on,
5464 .syslog = selinux_syslog,
5465 .vm_enough_memory = selinux_vm_enough_memory,
5466
5467 .netlink_send = selinux_netlink_send,
5468 .netlink_recv = selinux_netlink_recv,
5469
5470 .bprm_set_creds = selinux_bprm_set_creds,
5471 .bprm_committing_creds = selinux_bprm_committing_creds,
5472 .bprm_committed_creds = selinux_bprm_committed_creds,
5473 .bprm_secureexec = selinux_bprm_secureexec,
5474
5475 .sb_alloc_security = selinux_sb_alloc_security,
5476 .sb_free_security = selinux_sb_free_security,
5477 .sb_copy_data = selinux_sb_copy_data,
5478 .sb_remount = selinux_sb_remount,
5479 .sb_kern_mount = selinux_sb_kern_mount,
5480 .sb_show_options = selinux_sb_show_options,
5481 .sb_statfs = selinux_sb_statfs,
5482 .sb_mount = selinux_mount,
5483 .sb_umount = selinux_umount,
5484 .sb_set_mnt_opts = selinux_set_mnt_opts,
5485 .sb_clone_mnt_opts = selinux_sb_clone_mnt_opts,
5486 .sb_parse_opts_str = selinux_parse_opts_str,
5487
5488
5489 .inode_alloc_security = selinux_inode_alloc_security,
5490 .inode_free_security = selinux_inode_free_security,
5491 .inode_init_security = selinux_inode_init_security,
5492 .inode_create = selinux_inode_create,
5493 .inode_link = selinux_inode_link,
5494 .inode_unlink = selinux_inode_unlink,
5495 .inode_symlink = selinux_inode_symlink,
5496 .inode_mkdir = selinux_inode_mkdir,
5497 .inode_rmdir = selinux_inode_rmdir,
5498 .inode_mknod = selinux_inode_mknod,
5499 .inode_rename = selinux_inode_rename,
5500 .inode_readlink = selinux_inode_readlink,
5501 .inode_follow_link = selinux_inode_follow_link,
5502 .inode_permission = selinux_inode_permission,
5503 .inode_setattr = selinux_inode_setattr,
5504 .inode_getattr = selinux_inode_getattr,
5505 .inode_setxattr = selinux_inode_setxattr,
5506 .inode_post_setxattr = selinux_inode_post_setxattr,
5507 .inode_getxattr = selinux_inode_getxattr,
5508 .inode_listxattr = selinux_inode_listxattr,
5509 .inode_removexattr = selinux_inode_removexattr,
5510 .inode_getsecurity = selinux_inode_getsecurity,
5511 .inode_setsecurity = selinux_inode_setsecurity,
5512 .inode_listsecurity = selinux_inode_listsecurity,
5513 .inode_getsecid = selinux_inode_getsecid,
5514
5515 .file_permission = selinux_file_permission,
5516 .file_alloc_security = selinux_file_alloc_security,
5517 .file_free_security = selinux_file_free_security,
5518 .file_ioctl = selinux_file_ioctl,
5519 .file_mmap = selinux_file_mmap,
5520 .file_mprotect = selinux_file_mprotect,
5521 .file_lock = selinux_file_lock,
5522 .file_fcntl = selinux_file_fcntl,
5523 .file_set_fowner = selinux_file_set_fowner,
5524 .file_send_sigiotask = selinux_file_send_sigiotask,
5525 .file_receive = selinux_file_receive,
5526
5527 .dentry_open = selinux_dentry_open,
5528
5529 .task_create = selinux_task_create,
5530 .cred_alloc_blank = selinux_cred_alloc_blank,
5531 .cred_free = selinux_cred_free,
5532 .cred_prepare = selinux_cred_prepare,
5533 .cred_transfer = selinux_cred_transfer,
5534 .kernel_act_as = selinux_kernel_act_as,
5535 .kernel_create_files_as = selinux_kernel_create_files_as,
5536 .kernel_module_request = selinux_kernel_module_request,
5537 .task_setpgid = selinux_task_setpgid,
5538 .task_getpgid = selinux_task_getpgid,
5539 .task_getsid = selinux_task_getsid,
5540 .task_getsecid = selinux_task_getsecid,
5541 .task_setnice = selinux_task_setnice,
5542 .task_setioprio = selinux_task_setioprio,
5543 .task_getioprio = selinux_task_getioprio,
5544 .task_setrlimit = selinux_task_setrlimit,
5545 .task_setscheduler = selinux_task_setscheduler,
5546 .task_getscheduler = selinux_task_getscheduler,
5547 .task_movememory = selinux_task_movememory,
5548 .task_kill = selinux_task_kill,
5549 .task_wait = selinux_task_wait,
5550 .task_to_inode = selinux_task_to_inode,
5551
5552 .ipc_permission = selinux_ipc_permission,
5553 .ipc_getsecid = selinux_ipc_getsecid,
5554
5555 .msg_msg_alloc_security = selinux_msg_msg_alloc_security,
5556 .msg_msg_free_security = selinux_msg_msg_free_security,
5557
5558 .msg_queue_alloc_security = selinux_msg_queue_alloc_security,
5559 .msg_queue_free_security = selinux_msg_queue_free_security,
5560 .msg_queue_associate = selinux_msg_queue_associate,
5561 .msg_queue_msgctl = selinux_msg_queue_msgctl,
5562 .msg_queue_msgsnd = selinux_msg_queue_msgsnd,
5563 .msg_queue_msgrcv = selinux_msg_queue_msgrcv,
5564
5565 .shm_alloc_security = selinux_shm_alloc_security,
5566 .shm_free_security = selinux_shm_free_security,
5567 .shm_associate = selinux_shm_associate,
5568 .shm_shmctl = selinux_shm_shmctl,
5569 .shm_shmat = selinux_shm_shmat,
5570
5571 .sem_alloc_security = selinux_sem_alloc_security,
5572 .sem_free_security = selinux_sem_free_security,
5573 .sem_associate = selinux_sem_associate,
5574 .sem_semctl = selinux_sem_semctl,
5575 .sem_semop = selinux_sem_semop,
5576
5577 .d_instantiate = selinux_d_instantiate,
5578
5579 .getprocattr = selinux_getprocattr,
5580 .setprocattr = selinux_setprocattr,
5581
5582 .secid_to_secctx = selinux_secid_to_secctx,
5583 .secctx_to_secid = selinux_secctx_to_secid,
5584 .release_secctx = selinux_release_secctx,
5585 .inode_notifysecctx = selinux_inode_notifysecctx,
5586 .inode_setsecctx = selinux_inode_setsecctx,
5587 .inode_getsecctx = selinux_inode_getsecctx,
5588
5589 .unix_stream_connect = selinux_socket_unix_stream_connect,
5590 .unix_may_send = selinux_socket_unix_may_send,
5591
5592 .socket_create = selinux_socket_create,
5593 .socket_post_create = selinux_socket_post_create,
5594 .socket_bind = selinux_socket_bind,
5595 .socket_connect = selinux_socket_connect,
5596 .socket_listen = selinux_socket_listen,
5597 .socket_accept = selinux_socket_accept,
5598 .socket_sendmsg = selinux_socket_sendmsg,
5599 .socket_recvmsg = selinux_socket_recvmsg,
5600 .socket_getsockname = selinux_socket_getsockname,
5601 .socket_getpeername = selinux_socket_getpeername,
5602 .socket_getsockopt = selinux_socket_getsockopt,
5603 .socket_setsockopt = selinux_socket_setsockopt,
5604 .socket_shutdown = selinux_socket_shutdown,
5605 .socket_sock_rcv_skb = selinux_socket_sock_rcv_skb,
5606 .socket_getpeersec_stream = selinux_socket_getpeersec_stream,
5607 .socket_getpeersec_dgram = selinux_socket_getpeersec_dgram,
5608 .sk_alloc_security = selinux_sk_alloc_security,
5609 .sk_free_security = selinux_sk_free_security,
5610 .sk_clone_security = selinux_sk_clone_security,
5611 .sk_getsecid = selinux_sk_getsecid,
5612 .sock_graft = selinux_sock_graft,
5613 .inet_conn_request = selinux_inet_conn_request,
5614 .inet_csk_clone = selinux_inet_csk_clone,
5615 .inet_conn_established = selinux_inet_conn_established,
5616 .secmark_relabel_packet = selinux_secmark_relabel_packet,
5617 .secmark_refcount_inc = selinux_secmark_refcount_inc,
5618 .secmark_refcount_dec = selinux_secmark_refcount_dec,
5619 .req_classify_flow = selinux_req_classify_flow,
5620 .tun_dev_create = selinux_tun_dev_create,
5621 .tun_dev_post_create = selinux_tun_dev_post_create,
5622 .tun_dev_attach = selinux_tun_dev_attach,
5623
5624 #ifdef CONFIG_SECURITY_NETWORK_XFRM
5625 .xfrm_policy_alloc_security = selinux_xfrm_policy_alloc,
5626 .xfrm_policy_clone_security = selinux_xfrm_policy_clone,
5627 .xfrm_policy_free_security = selinux_xfrm_policy_free,
5628 .xfrm_policy_delete_security = selinux_xfrm_policy_delete,
5629 .xfrm_state_alloc_security = selinux_xfrm_state_alloc,
5630 .xfrm_state_free_security = selinux_xfrm_state_free,
5631 .xfrm_state_delete_security = selinux_xfrm_state_delete,
5632 .xfrm_policy_lookup = selinux_xfrm_policy_lookup,
5633 .xfrm_state_pol_flow_match = selinux_xfrm_state_pol_flow_match,
5634 .xfrm_decode_session = selinux_xfrm_decode_session,
5635 #endif
5636
5637 #ifdef CONFIG_KEYS
5638 .key_alloc = selinux_key_alloc,
5639 .key_free = selinux_key_free,
5640 .key_permission = selinux_key_permission,
5641 .key_getsecurity = selinux_key_getsecurity,
5642 #endif
5643
5644 #ifdef CONFIG_AUDIT
5645 .audit_rule_init = selinux_audit_rule_init,
5646 .audit_rule_known = selinux_audit_rule_known,
5647 .audit_rule_match = selinux_audit_rule_match,
5648 .audit_rule_free = selinux_audit_rule_free,
5649 #endif
5650 };
5651
5652 static __init int selinux_init(void)
5653 {
5654 if (!security_module_enable(&selinux_ops)) {
5655 selinux_enabled = 0;
5656 return 0;
5657 }
5658
5659 if (!selinux_enabled) {
5660 printk(KERN_INFO "SELinux: Disabled at boot.\n");
5661 return 0;
5662 }
5663
5664 printk(KERN_INFO "SELinux: Initializing.\n");
5665
5666 /* Set the security state for the initial task. */
5667 cred_init_security();
5668
5669 default_noexec = !(VM_DATA_DEFAULT_FLAGS & VM_EXEC);
5670
5671 sel_inode_cache = kmem_cache_create("selinux_inode_security",
5672 sizeof(struct inode_security_struct),
5673 0, SLAB_PANIC, NULL);
5674 avc_init();
5675
5676 if (register_security(&selinux_ops))
5677 panic("SELinux: Unable to register with kernel.\n");
5678
5679 if (selinux_enforcing)
5680 printk(KERN_DEBUG "SELinux: Starting in enforcing mode\n");
5681 else
5682 printk(KERN_DEBUG "SELinux: Starting in permissive mode\n");
5683
5684 return 0;
5685 }
5686
5687 static void delayed_superblock_init(struct super_block *sb, void *unused)
5688 {
5689 superblock_doinit(sb, NULL);
5690 }
5691
5692 void selinux_complete_init(void)
5693 {
5694 printk(KERN_DEBUG "SELinux: Completing initialization.\n");
5695
5696 /* Set up any superblocks initialized prior to the policy load. */
5697 printk(KERN_DEBUG "SELinux: Setting up existing superblocks.\n");
5698 iterate_supers(delayed_superblock_init, NULL);
5699 }
5700
5701 /* SELinux requires early initialization in order to label
5702 all processes and objects when they are created. */
5703 security_initcall(selinux_init);
5704
5705 #if defined(CONFIG_NETFILTER)
5706
5707 static struct nf_hook_ops selinux_ipv4_ops[] = {
5708 {
5709 .hook = selinux_ipv4_postroute,
5710 .owner = THIS_MODULE,
5711 .pf = PF_INET,
5712 .hooknum = NF_INET_POST_ROUTING,
5713 .priority = NF_IP_PRI_SELINUX_LAST,
5714 },
5715 {
5716 .hook = selinux_ipv4_forward,
5717 .owner = THIS_MODULE,
5718 .pf = PF_INET,
5719 .hooknum = NF_INET_FORWARD,
5720 .priority = NF_IP_PRI_SELINUX_FIRST,
5721 },
5722 {
5723 .hook = selinux_ipv4_output,
5724 .owner = THIS_MODULE,
5725 .pf = PF_INET,
5726 .hooknum = NF_INET_LOCAL_OUT,
5727 .priority = NF_IP_PRI_SELINUX_FIRST,
5728 }
5729 };
5730
5731 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
5732
5733 static struct nf_hook_ops selinux_ipv6_ops[] = {
5734 {
5735 .hook = selinux_ipv6_postroute,
5736 .owner = THIS_MODULE,
5737 .pf = PF_INET6,
5738 .hooknum = NF_INET_POST_ROUTING,
5739 .priority = NF_IP6_PRI_SELINUX_LAST,
5740 },
5741 {
5742 .hook = selinux_ipv6_forward,
5743 .owner = THIS_MODULE,
5744 .pf = PF_INET6,
5745 .hooknum = NF_INET_FORWARD,
5746 .priority = NF_IP6_PRI_SELINUX_FIRST,
5747 }
5748 };
5749
5750 #endif /* IPV6 */
5751
5752 static int __init selinux_nf_ip_init(void)
5753 {
5754 int err = 0;
5755
5756 if (!selinux_enabled)
5757 goto out;
5758
5759 printk(KERN_DEBUG "SELinux: Registering netfilter hooks\n");
5760
5761 err = nf_register_hooks(selinux_ipv4_ops, ARRAY_SIZE(selinux_ipv4_ops));
5762 if (err)
5763 panic("SELinux: nf_register_hooks for IPv4: error %d\n", err);
5764
5765 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
5766 err = nf_register_hooks(selinux_ipv6_ops, ARRAY_SIZE(selinux_ipv6_ops));
5767 if (err)
5768 panic("SELinux: nf_register_hooks for IPv6: error %d\n", err);
5769 #endif /* IPV6 */
5770
5771 out:
5772 return err;
5773 }
5774
5775 __initcall(selinux_nf_ip_init);
5776
5777 #ifdef CONFIG_SECURITY_SELINUX_DISABLE
5778 static void selinux_nf_ip_exit(void)
5779 {
5780 printk(KERN_DEBUG "SELinux: Unregistering netfilter hooks\n");
5781
5782 nf_unregister_hooks(selinux_ipv4_ops, ARRAY_SIZE(selinux_ipv4_ops));
5783 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
5784 nf_unregister_hooks(selinux_ipv6_ops, ARRAY_SIZE(selinux_ipv6_ops));
5785 #endif /* IPV6 */
5786 }
5787 #endif
5788
5789 #else /* CONFIG_NETFILTER */
5790
5791 #ifdef CONFIG_SECURITY_SELINUX_DISABLE
5792 #define selinux_nf_ip_exit()
5793 #endif
5794
5795 #endif /* CONFIG_NETFILTER */
5796
5797 #ifdef CONFIG_SECURITY_SELINUX_DISABLE
5798 static int selinux_disabled;
5799
5800 int selinux_disable(void)
5801 {
5802 if (ss_initialized) {
5803 /* Not permitted after initial policy load. */
5804 return -EINVAL;
5805 }
5806
5807 if (selinux_disabled) {
5808 /* Only do this once. */
5809 return -EINVAL;
5810 }
5811
5812 printk(KERN_INFO "SELinux: Disabled at runtime.\n");
5813
5814 selinux_disabled = 1;
5815 selinux_enabled = 0;
5816
5817 reset_security_ops();
5818
5819 /* Try to destroy the avc node cache */
5820 avc_disable();
5821
5822 /* Unregister netfilter hooks. */
5823 selinux_nf_ip_exit();
5824
5825 /* Unregister selinuxfs. */
5826 exit_sel_fs();
5827
5828 return 0;
5829 }
5830 #endif
Linux kernel - Deliverables
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