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Merge branch 'ptrace' of git://git.kernel.org/pub/scm/linux/kernel/git/oleg/misc
[mirror_ubuntu-zesty-kernel.git] / security / selinux / hooks.c
1 /*
2 * NSA Security-Enhanced Linux (SELinux) security module
3 *
4 * This file contains the SELinux hook function implementations.
5 *
6 * Authors: Stephen Smalley, <sds@epoch.ncsc.mil>
7 * Chris Vance, <cvance@nai.com>
8 * Wayne Salamon, <wsalamon@nai.com>
9 * James Morris <jmorris@redhat.com>
10 *
11 * Copyright (C) 2001,2002 Networks Associates Technology, Inc.
12 * Copyright (C) 2003-2008 Red Hat, Inc., James Morris <jmorris@redhat.com>
13 * Eric Paris <eparis@redhat.com>
14 * Copyright (C) 2004-2005 Trusted Computer Solutions, Inc.
15 * <dgoeddel@trustedcs.com>
16 * Copyright (C) 2006, 2007, 2009 Hewlett-Packard Development Company, L.P.
17 * Paul Moore <paul.moore@hp.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 <asm/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 int selinux_nlmsg_lookup(u16 sclass, u16 nlmsg_type, u32 *perm);
96 extern struct security_operations *security_ops;
97
98 /* SECMARK reference count */
99 atomic_t selinux_secmark_refcount = ATOMIC_INIT(0);
100
101 #ifdef CONFIG_SECURITY_SELINUX_DEVELOP
102 int selinux_enforcing;
103
104 static int __init enforcing_setup(char *str)
105 {
106 unsigned long enforcing;
107 if (!strict_strtoul(str, 0, &enforcing))
108 selinux_enforcing = enforcing ? 1 : 0;
109 return 1;
110 }
111 __setup("enforcing=", enforcing_setup);
112 #endif
113
114 #ifdef CONFIG_SECURITY_SELINUX_BOOTPARAM
115 int selinux_enabled = CONFIG_SECURITY_SELINUX_BOOTPARAM_VALUE;
116
117 static int __init selinux_enabled_setup(char *str)
118 {
119 unsigned long enabled;
120 if (!strict_strtoul(str, 0, &enabled))
121 selinux_enabled = enabled ? 1 : 0;
122 return 1;
123 }
124 __setup("selinux=", selinux_enabled_setup);
125 #else
126 int selinux_enabled = 1;
127 #endif
128
129 static struct kmem_cache *sel_inode_cache;
130
131 /**
132 * selinux_secmark_enabled - Check to see if SECMARK is currently enabled
133 *
134 * Description:
135 * This function checks the SECMARK reference counter to see if any SECMARK
136 * targets are currently configured, if the reference counter is greater than
137 * zero SECMARK is considered to be enabled. Returns true (1) if SECMARK is
138 * enabled, false (0) if SECMARK is disabled.
139 *
140 */
141 static int selinux_secmark_enabled(void)
142 {
143 return (atomic_read(&selinux_secmark_refcount) > 0);
144 }
145
146 /*
147 * initialise the security for the init task
148 */
149 static void cred_init_security(void)
150 {
151 struct cred *cred = (struct cred *) current->real_cred;
152 struct task_security_struct *tsec;
153
154 tsec = kzalloc(sizeof(struct task_security_struct), GFP_KERNEL);
155 if (!tsec)
156 panic("SELinux: Failed to initialize initial task.\n");
157
158 tsec->osid = tsec->sid = SECINITSID_KERNEL;
159 cred->security = tsec;
160 }
161
162 /*
163 * get the security ID of a set of credentials
164 */
165 static inline u32 cred_sid(const struct cred *cred)
166 {
167 const struct task_security_struct *tsec;
168
169 tsec = cred->security;
170 return tsec->sid;
171 }
172
173 /*
174 * get the objective security ID of a task
175 */
176 static inline u32 task_sid(const struct task_struct *task)
177 {
178 u32 sid;
179
180 rcu_read_lock();
181 sid = cred_sid(__task_cred(task));
182 rcu_read_unlock();
183 return sid;
184 }
185
186 /*
187 * get the subjective security ID of the current task
188 */
189 static inline u32 current_sid(void)
190 {
191 const struct task_security_struct *tsec = current_security();
192
193 return tsec->sid;
194 }
195
196 /* Allocate and free functions for each kind of security blob. */
197
198 static int inode_alloc_security(struct inode *inode)
199 {
200 struct inode_security_struct *isec;
201 u32 sid = current_sid();
202
203 isec = kmem_cache_zalloc(sel_inode_cache, GFP_NOFS);
204 if (!isec)
205 return -ENOMEM;
206
207 mutex_init(&isec->lock);
208 INIT_LIST_HEAD(&isec->list);
209 isec->inode = inode;
210 isec->sid = SECINITSID_UNLABELED;
211 isec->sclass = SECCLASS_FILE;
212 isec->task_sid = sid;
213 inode->i_security = isec;
214
215 return 0;
216 }
217
218 static void inode_free_security(struct inode *inode)
219 {
220 struct inode_security_struct *isec = inode->i_security;
221 struct superblock_security_struct *sbsec = inode->i_sb->s_security;
222
223 spin_lock(&sbsec->isec_lock);
224 if (!list_empty(&isec->list))
225 list_del_init(&isec->list);
226 spin_unlock(&sbsec->isec_lock);
227
228 inode->i_security = NULL;
229 kmem_cache_free(sel_inode_cache, isec);
230 }
231
232 static int file_alloc_security(struct file *file)
233 {
234 struct file_security_struct *fsec;
235 u32 sid = current_sid();
236
237 fsec = kzalloc(sizeof(struct file_security_struct), GFP_KERNEL);
238 if (!fsec)
239 return -ENOMEM;
240
241 fsec->sid = sid;
242 fsec->fown_sid = sid;
243 file->f_security = fsec;
244
245 return 0;
246 }
247
248 static void file_free_security(struct file *file)
249 {
250 struct file_security_struct *fsec = file->f_security;
251 file->f_security = NULL;
252 kfree(fsec);
253 }
254
255 static int superblock_alloc_security(struct super_block *sb)
256 {
257 struct superblock_security_struct *sbsec;
258
259 sbsec = kzalloc(sizeof(struct superblock_security_struct), GFP_KERNEL);
260 if (!sbsec)
261 return -ENOMEM;
262
263 mutex_init(&sbsec->lock);
264 INIT_LIST_HEAD(&sbsec->isec_head);
265 spin_lock_init(&sbsec->isec_lock);
266 sbsec->sb = sb;
267 sbsec->sid = SECINITSID_UNLABELED;
268 sbsec->def_sid = SECINITSID_FILE;
269 sbsec->mntpoint_sid = SECINITSID_UNLABELED;
270 sb->s_security = sbsec;
271
272 return 0;
273 }
274
275 static void superblock_free_security(struct super_block *sb)
276 {
277 struct superblock_security_struct *sbsec = sb->s_security;
278 sb->s_security = NULL;
279 kfree(sbsec);
280 }
281
282 /* The security server must be initialized before
283 any labeling or access decisions can be provided. */
284 extern int ss_initialized;
285
286 /* The file system's label must be initialized prior to use. */
287
288 static const char *labeling_behaviors[6] = {
289 "uses xattr",
290 "uses transition SIDs",
291 "uses task SIDs",
292 "uses genfs_contexts",
293 "not configured for labeling",
294 "uses mountpoint labeling",
295 };
296
297 static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dentry);
298
299 static inline int inode_doinit(struct inode *inode)
300 {
301 return inode_doinit_with_dentry(inode, NULL);
302 }
303
304 enum {
305 Opt_error = -1,
306 Opt_context = 1,
307 Opt_fscontext = 2,
308 Opt_defcontext = 3,
309 Opt_rootcontext = 4,
310 Opt_labelsupport = 5,
311 };
312
313 static const match_table_t tokens = {
314 {Opt_context, CONTEXT_STR "%s"},
315 {Opt_fscontext, FSCONTEXT_STR "%s"},
316 {Opt_defcontext, DEFCONTEXT_STR "%s"},
317 {Opt_rootcontext, ROOTCONTEXT_STR "%s"},
318 {Opt_labelsupport, LABELSUPP_STR},
319 {Opt_error, NULL},
320 };
321
322 #define SEL_MOUNT_FAIL_MSG "SELinux: duplicate or incompatible mount options\n"
323
324 static int may_context_mount_sb_relabel(u32 sid,
325 struct superblock_security_struct *sbsec,
326 const struct cred *cred)
327 {
328 const struct task_security_struct *tsec = cred->security;
329 int rc;
330
331 rc = avc_has_perm(tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM,
332 FILESYSTEM__RELABELFROM, NULL);
333 if (rc)
334 return rc;
335
336 rc = avc_has_perm(tsec->sid, sid, SECCLASS_FILESYSTEM,
337 FILESYSTEM__RELABELTO, NULL);
338 return rc;
339 }
340
341 static int may_context_mount_inode_relabel(u32 sid,
342 struct superblock_security_struct *sbsec,
343 const struct cred *cred)
344 {
345 const struct task_security_struct *tsec = cred->security;
346 int rc;
347 rc = avc_has_perm(tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM,
348 FILESYSTEM__RELABELFROM, NULL);
349 if (rc)
350 return rc;
351
352 rc = avc_has_perm(sid, sbsec->sid, SECCLASS_FILESYSTEM,
353 FILESYSTEM__ASSOCIATE, NULL);
354 return rc;
355 }
356
357 static int sb_finish_set_opts(struct super_block *sb)
358 {
359 struct superblock_security_struct *sbsec = sb->s_security;
360 struct dentry *root = sb->s_root;
361 struct inode *root_inode = root->d_inode;
362 int rc = 0;
363
364 if (sbsec->behavior == SECURITY_FS_USE_XATTR) {
365 /* Make sure that the xattr handler exists and that no
366 error other than -ENODATA is returned by getxattr on
367 the root directory. -ENODATA is ok, as this may be
368 the first boot of the SELinux kernel before we have
369 assigned xattr values to the filesystem. */
370 if (!root_inode->i_op->getxattr) {
371 printk(KERN_WARNING "SELinux: (dev %s, type %s) has no "
372 "xattr support\n", sb->s_id, sb->s_type->name);
373 rc = -EOPNOTSUPP;
374 goto out;
375 }
376 rc = root_inode->i_op->getxattr(root, XATTR_NAME_SELINUX, NULL, 0);
377 if (rc < 0 && rc != -ENODATA) {
378 if (rc == -EOPNOTSUPP)
379 printk(KERN_WARNING "SELinux: (dev %s, type "
380 "%s) has no security xattr handler\n",
381 sb->s_id, sb->s_type->name);
382 else
383 printk(KERN_WARNING "SELinux: (dev %s, type "
384 "%s) getxattr errno %d\n", sb->s_id,
385 sb->s_type->name, -rc);
386 goto out;
387 }
388 }
389
390 sbsec->flags |= (SE_SBINITIALIZED | SE_SBLABELSUPP);
391
392 if (sbsec->behavior > ARRAY_SIZE(labeling_behaviors))
393 printk(KERN_ERR "SELinux: initialized (dev %s, type %s), unknown behavior\n",
394 sb->s_id, sb->s_type->name);
395 else
396 printk(KERN_DEBUG "SELinux: initialized (dev %s, type %s), %s\n",
397 sb->s_id, sb->s_type->name,
398 labeling_behaviors[sbsec->behavior-1]);
399
400 if (sbsec->behavior == SECURITY_FS_USE_GENFS ||
401 sbsec->behavior == SECURITY_FS_USE_MNTPOINT ||
402 sbsec->behavior == SECURITY_FS_USE_NONE ||
403 sbsec->behavior > ARRAY_SIZE(labeling_behaviors))
404 sbsec->flags &= ~SE_SBLABELSUPP;
405
406 /* Special handling for sysfs. Is genfs but also has setxattr handler*/
407 if (strncmp(sb->s_type->name, "sysfs", sizeof("sysfs")) == 0)
408 sbsec->flags |= SE_SBLABELSUPP;
409
410 /* Initialize the root inode. */
411 rc = inode_doinit_with_dentry(root_inode, root);
412
413 /* Initialize any other inodes associated with the superblock, e.g.
414 inodes created prior to initial policy load or inodes created
415 during get_sb by a pseudo filesystem that directly
416 populates itself. */
417 spin_lock(&sbsec->isec_lock);
418 next_inode:
419 if (!list_empty(&sbsec->isec_head)) {
420 struct inode_security_struct *isec =
421 list_entry(sbsec->isec_head.next,
422 struct inode_security_struct, list);
423 struct inode *inode = isec->inode;
424 spin_unlock(&sbsec->isec_lock);
425 inode = igrab(inode);
426 if (inode) {
427 if (!IS_PRIVATE(inode))
428 inode_doinit(inode);
429 iput(inode);
430 }
431 spin_lock(&sbsec->isec_lock);
432 list_del_init(&isec->list);
433 goto next_inode;
434 }
435 spin_unlock(&sbsec->isec_lock);
436 out:
437 return rc;
438 }
439
440 /*
441 * This function should allow an FS to ask what it's mount security
442 * options were so it can use those later for submounts, displaying
443 * mount options, or whatever.
444 */
445 static int selinux_get_mnt_opts(const struct super_block *sb,
446 struct security_mnt_opts *opts)
447 {
448 int rc = 0, i;
449 struct superblock_security_struct *sbsec = sb->s_security;
450 char *context = NULL;
451 u32 len;
452 char tmp;
453
454 security_init_mnt_opts(opts);
455
456 if (!(sbsec->flags & SE_SBINITIALIZED))
457 return -EINVAL;
458
459 if (!ss_initialized)
460 return -EINVAL;
461
462 tmp = sbsec->flags & SE_MNTMASK;
463 /* count the number of mount options for this sb */
464 for (i = 0; i < 8; i++) {
465 if (tmp & 0x01)
466 opts->num_mnt_opts++;
467 tmp >>= 1;
468 }
469 /* Check if the Label support flag is set */
470 if (sbsec->flags & SE_SBLABELSUPP)
471 opts->num_mnt_opts++;
472
473 opts->mnt_opts = kcalloc(opts->num_mnt_opts, sizeof(char *), GFP_ATOMIC);
474 if (!opts->mnt_opts) {
475 rc = -ENOMEM;
476 goto out_free;
477 }
478
479 opts->mnt_opts_flags = kcalloc(opts->num_mnt_opts, sizeof(int), GFP_ATOMIC);
480 if (!opts->mnt_opts_flags) {
481 rc = -ENOMEM;
482 goto out_free;
483 }
484
485 i = 0;
486 if (sbsec->flags & FSCONTEXT_MNT) {
487 rc = security_sid_to_context(sbsec->sid, &context, &len);
488 if (rc)
489 goto out_free;
490 opts->mnt_opts[i] = context;
491 opts->mnt_opts_flags[i++] = FSCONTEXT_MNT;
492 }
493 if (sbsec->flags & CONTEXT_MNT) {
494 rc = security_sid_to_context(sbsec->mntpoint_sid, &context, &len);
495 if (rc)
496 goto out_free;
497 opts->mnt_opts[i] = context;
498 opts->mnt_opts_flags[i++] = CONTEXT_MNT;
499 }
500 if (sbsec->flags & DEFCONTEXT_MNT) {
501 rc = security_sid_to_context(sbsec->def_sid, &context, &len);
502 if (rc)
503 goto out_free;
504 opts->mnt_opts[i] = context;
505 opts->mnt_opts_flags[i++] = DEFCONTEXT_MNT;
506 }
507 if (sbsec->flags & ROOTCONTEXT_MNT) {
508 struct inode *root = sbsec->sb->s_root->d_inode;
509 struct inode_security_struct *isec = root->i_security;
510
511 rc = security_sid_to_context(isec->sid, &context, &len);
512 if (rc)
513 goto out_free;
514 opts->mnt_opts[i] = context;
515 opts->mnt_opts_flags[i++] = ROOTCONTEXT_MNT;
516 }
517 if (sbsec->flags & SE_SBLABELSUPP) {
518 opts->mnt_opts[i] = NULL;
519 opts->mnt_opts_flags[i++] = SE_SBLABELSUPP;
520 }
521
522 BUG_ON(i != opts->num_mnt_opts);
523
524 return 0;
525
526 out_free:
527 security_free_mnt_opts(opts);
528 return rc;
529 }
530
531 static int bad_option(struct superblock_security_struct *sbsec, char flag,
532 u32 old_sid, u32 new_sid)
533 {
534 char mnt_flags = sbsec->flags & SE_MNTMASK;
535
536 /* check if the old mount command had the same options */
537 if (sbsec->flags & SE_SBINITIALIZED)
538 if (!(sbsec->flags & flag) ||
539 (old_sid != new_sid))
540 return 1;
541
542 /* check if we were passed the same options twice,
543 * aka someone passed context=a,context=b
544 */
545 if (!(sbsec->flags & SE_SBINITIALIZED))
546 if (mnt_flags & flag)
547 return 1;
548 return 0;
549 }
550
551 /*
552 * Allow filesystems with binary mount data to explicitly set mount point
553 * labeling information.
554 */
555 static int selinux_set_mnt_opts(struct super_block *sb,
556 struct security_mnt_opts *opts)
557 {
558 const struct cred *cred = current_cred();
559 int rc = 0, i;
560 struct superblock_security_struct *sbsec = sb->s_security;
561 const char *name = sb->s_type->name;
562 struct inode *inode = sbsec->sb->s_root->d_inode;
563 struct inode_security_struct *root_isec = inode->i_security;
564 u32 fscontext_sid = 0, context_sid = 0, rootcontext_sid = 0;
565 u32 defcontext_sid = 0;
566 char **mount_options = opts->mnt_opts;
567 int *flags = opts->mnt_opts_flags;
568 int num_opts = opts->num_mnt_opts;
569
570 mutex_lock(&sbsec->lock);
571
572 if (!ss_initialized) {
573 if (!num_opts) {
574 /* Defer initialization until selinux_complete_init,
575 after the initial policy is loaded and the security
576 server is ready to handle calls. */
577 goto out;
578 }
579 rc = -EINVAL;
580 printk(KERN_WARNING "SELinux: Unable to set superblock options "
581 "before the security server is initialized\n");
582 goto out;
583 }
584
585 /*
586 * Binary mount data FS will come through this function twice. Once
587 * from an explicit call and once from the generic calls from the vfs.
588 * Since the generic VFS calls will not contain any security mount data
589 * we need to skip the double mount verification.
590 *
591 * This does open a hole in which we will not notice if the first
592 * mount using this sb set explict options and a second mount using
593 * this sb does not set any security options. (The first options
594 * will be used for both mounts)
595 */
596 if ((sbsec->flags & SE_SBINITIALIZED) && (sb->s_type->fs_flags & FS_BINARY_MOUNTDATA)
597 && (num_opts == 0))
598 goto out;
599
600 /*
601 * parse the mount options, check if they are valid sids.
602 * also check if someone is trying to mount the same sb more
603 * than once with different security options.
604 */
605 for (i = 0; i < num_opts; i++) {
606 u32 sid;
607
608 if (flags[i] == SE_SBLABELSUPP)
609 continue;
610 rc = security_context_to_sid(mount_options[i],
611 strlen(mount_options[i]), &sid);
612 if (rc) {
613 printk(KERN_WARNING "SELinux: security_context_to_sid"
614 "(%s) failed for (dev %s, type %s) errno=%d\n",
615 mount_options[i], sb->s_id, name, rc);
616 goto out;
617 }
618 switch (flags[i]) {
619 case FSCONTEXT_MNT:
620 fscontext_sid = sid;
621
622 if (bad_option(sbsec, FSCONTEXT_MNT, sbsec->sid,
623 fscontext_sid))
624 goto out_double_mount;
625
626 sbsec->flags |= FSCONTEXT_MNT;
627 break;
628 case CONTEXT_MNT:
629 context_sid = sid;
630
631 if (bad_option(sbsec, CONTEXT_MNT, sbsec->mntpoint_sid,
632 context_sid))
633 goto out_double_mount;
634
635 sbsec->flags |= CONTEXT_MNT;
636 break;
637 case ROOTCONTEXT_MNT:
638 rootcontext_sid = sid;
639
640 if (bad_option(sbsec, ROOTCONTEXT_MNT, root_isec->sid,
641 rootcontext_sid))
642 goto out_double_mount;
643
644 sbsec->flags |= ROOTCONTEXT_MNT;
645
646 break;
647 case DEFCONTEXT_MNT:
648 defcontext_sid = sid;
649
650 if (bad_option(sbsec, DEFCONTEXT_MNT, sbsec->def_sid,
651 defcontext_sid))
652 goto out_double_mount;
653
654 sbsec->flags |= DEFCONTEXT_MNT;
655
656 break;
657 default:
658 rc = -EINVAL;
659 goto out;
660 }
661 }
662
663 if (sbsec->flags & SE_SBINITIALIZED) {
664 /* previously mounted with options, but not on this attempt? */
665 if ((sbsec->flags & SE_MNTMASK) && !num_opts)
666 goto out_double_mount;
667 rc = 0;
668 goto out;
669 }
670
671 if (strcmp(sb->s_type->name, "proc") == 0)
672 sbsec->flags |= SE_SBPROC;
673
674 /* Determine the labeling behavior to use for this filesystem type. */
675 rc = security_fs_use((sbsec->flags & SE_SBPROC) ? "proc" : sb->s_type->name, &sbsec->behavior, &sbsec->sid);
676 if (rc) {
677 printk(KERN_WARNING "%s: security_fs_use(%s) returned %d\n",
678 __func__, sb->s_type->name, rc);
679 goto out;
680 }
681
682 /* sets the context of the superblock for the fs being mounted. */
683 if (fscontext_sid) {
684 rc = may_context_mount_sb_relabel(fscontext_sid, sbsec, cred);
685 if (rc)
686 goto out;
687
688 sbsec->sid = fscontext_sid;
689 }
690
691 /*
692 * Switch to using mount point labeling behavior.
693 * sets the label used on all file below the mountpoint, and will set
694 * the superblock context if not already set.
695 */
696 if (context_sid) {
697 if (!fscontext_sid) {
698 rc = may_context_mount_sb_relabel(context_sid, sbsec,
699 cred);
700 if (rc)
701 goto out;
702 sbsec->sid = context_sid;
703 } else {
704 rc = may_context_mount_inode_relabel(context_sid, sbsec,
705 cred);
706 if (rc)
707 goto out;
708 }
709 if (!rootcontext_sid)
710 rootcontext_sid = context_sid;
711
712 sbsec->mntpoint_sid = context_sid;
713 sbsec->behavior = SECURITY_FS_USE_MNTPOINT;
714 }
715
716 if (rootcontext_sid) {
717 rc = may_context_mount_inode_relabel(rootcontext_sid, sbsec,
718 cred);
719 if (rc)
720 goto out;
721
722 root_isec->sid = rootcontext_sid;
723 root_isec->initialized = 1;
724 }
725
726 if (defcontext_sid) {
727 if (sbsec->behavior != SECURITY_FS_USE_XATTR) {
728 rc = -EINVAL;
729 printk(KERN_WARNING "SELinux: defcontext option is "
730 "invalid for this filesystem type\n");
731 goto out;
732 }
733
734 if (defcontext_sid != sbsec->def_sid) {
735 rc = may_context_mount_inode_relabel(defcontext_sid,
736 sbsec, cred);
737 if (rc)
738 goto out;
739 }
740
741 sbsec->def_sid = defcontext_sid;
742 }
743
744 rc = sb_finish_set_opts(sb);
745 out:
746 mutex_unlock(&sbsec->lock);
747 return rc;
748 out_double_mount:
749 rc = -EINVAL;
750 printk(KERN_WARNING "SELinux: mount invalid. Same superblock, different "
751 "security settings for (dev %s, type %s)\n", sb->s_id, name);
752 goto out;
753 }
754
755 static void selinux_sb_clone_mnt_opts(const struct super_block *oldsb,
756 struct super_block *newsb)
757 {
758 const struct superblock_security_struct *oldsbsec = oldsb->s_security;
759 struct superblock_security_struct *newsbsec = newsb->s_security;
760
761 int set_fscontext = (oldsbsec->flags & FSCONTEXT_MNT);
762 int set_context = (oldsbsec->flags & CONTEXT_MNT);
763 int set_rootcontext = (oldsbsec->flags & ROOTCONTEXT_MNT);
764
765 /*
766 * if the parent was able to be mounted it clearly had no special lsm
767 * mount options. thus we can safely deal with this superblock later
768 */
769 if (!ss_initialized)
770 return;
771
772 /* how can we clone if the old one wasn't set up?? */
773 BUG_ON(!(oldsbsec->flags & SE_SBINITIALIZED));
774
775 /* if fs is reusing a sb, just let its options stand... */
776 if (newsbsec->flags & SE_SBINITIALIZED)
777 return;
778
779 mutex_lock(&newsbsec->lock);
780
781 newsbsec->flags = oldsbsec->flags;
782
783 newsbsec->sid = oldsbsec->sid;
784 newsbsec->def_sid = oldsbsec->def_sid;
785 newsbsec->behavior = oldsbsec->behavior;
786
787 if (set_context) {
788 u32 sid = oldsbsec->mntpoint_sid;
789
790 if (!set_fscontext)
791 newsbsec->sid = sid;
792 if (!set_rootcontext) {
793 struct inode *newinode = newsb->s_root->d_inode;
794 struct inode_security_struct *newisec = newinode->i_security;
795 newisec->sid = sid;
796 }
797 newsbsec->mntpoint_sid = sid;
798 }
799 if (set_rootcontext) {
800 const struct inode *oldinode = oldsb->s_root->d_inode;
801 const struct inode_security_struct *oldisec = oldinode->i_security;
802 struct inode *newinode = newsb->s_root->d_inode;
803 struct inode_security_struct *newisec = newinode->i_security;
804
805 newisec->sid = oldisec->sid;
806 }
807
808 sb_finish_set_opts(newsb);
809 mutex_unlock(&newsbsec->lock);
810 }
811
812 static int selinux_parse_opts_str(char *options,
813 struct security_mnt_opts *opts)
814 {
815 char *p;
816 char *context = NULL, *defcontext = NULL;
817 char *fscontext = NULL, *rootcontext = NULL;
818 int rc, num_mnt_opts = 0;
819
820 opts->num_mnt_opts = 0;
821
822 /* Standard string-based options. */
823 while ((p = strsep(&options, "|")) != NULL) {
824 int token;
825 substring_t args[MAX_OPT_ARGS];
826
827 if (!*p)
828 continue;
829
830 token = match_token(p, tokens, args);
831
832 switch (token) {
833 case Opt_context:
834 if (context || defcontext) {
835 rc = -EINVAL;
836 printk(KERN_WARNING SEL_MOUNT_FAIL_MSG);
837 goto out_err;
838 }
839 context = match_strdup(&args[0]);
840 if (!context) {
841 rc = -ENOMEM;
842 goto out_err;
843 }
844 break;
845
846 case Opt_fscontext:
847 if (fscontext) {
848 rc = -EINVAL;
849 printk(KERN_WARNING SEL_MOUNT_FAIL_MSG);
850 goto out_err;
851 }
852 fscontext = match_strdup(&args[0]);
853 if (!fscontext) {
854 rc = -ENOMEM;
855 goto out_err;
856 }
857 break;
858
859 case Opt_rootcontext:
860 if (rootcontext) {
861 rc = -EINVAL;
862 printk(KERN_WARNING SEL_MOUNT_FAIL_MSG);
863 goto out_err;
864 }
865 rootcontext = match_strdup(&args[0]);
866 if (!rootcontext) {
867 rc = -ENOMEM;
868 goto out_err;
869 }
870 break;
871
872 case Opt_defcontext:
873 if (context || defcontext) {
874 rc = -EINVAL;
875 printk(KERN_WARNING SEL_MOUNT_FAIL_MSG);
876 goto out_err;
877 }
878 defcontext = match_strdup(&args[0]);
879 if (!defcontext) {
880 rc = -ENOMEM;
881 goto out_err;
882 }
883 break;
884 case Opt_labelsupport:
885 break;
886 default:
887 rc = -EINVAL;
888 printk(KERN_WARNING "SELinux: unknown mount option\n");
889 goto out_err;
890
891 }
892 }
893
894 rc = -ENOMEM;
895 opts->mnt_opts = kcalloc(NUM_SEL_MNT_OPTS, sizeof(char *), GFP_ATOMIC);
896 if (!opts->mnt_opts)
897 goto out_err;
898
899 opts->mnt_opts_flags = kcalloc(NUM_SEL_MNT_OPTS, sizeof(int), GFP_ATOMIC);
900 if (!opts->mnt_opts_flags) {
901 kfree(opts->mnt_opts);
902 goto out_err;
903 }
904
905 if (fscontext) {
906 opts->mnt_opts[num_mnt_opts] = fscontext;
907 opts->mnt_opts_flags[num_mnt_opts++] = FSCONTEXT_MNT;
908 }
909 if (context) {
910 opts->mnt_opts[num_mnt_opts] = context;
911 opts->mnt_opts_flags[num_mnt_opts++] = CONTEXT_MNT;
912 }
913 if (rootcontext) {
914 opts->mnt_opts[num_mnt_opts] = rootcontext;
915 opts->mnt_opts_flags[num_mnt_opts++] = ROOTCONTEXT_MNT;
916 }
917 if (defcontext) {
918 opts->mnt_opts[num_mnt_opts] = defcontext;
919 opts->mnt_opts_flags[num_mnt_opts++] = DEFCONTEXT_MNT;
920 }
921
922 opts->num_mnt_opts = num_mnt_opts;
923 return 0;
924
925 out_err:
926 kfree(context);
927 kfree(defcontext);
928 kfree(fscontext);
929 kfree(rootcontext);
930 return rc;
931 }
932 /*
933 * string mount options parsing and call set the sbsec
934 */
935 static int superblock_doinit(struct super_block *sb, void *data)
936 {
937 int rc = 0;
938 char *options = data;
939 struct security_mnt_opts opts;
940
941 security_init_mnt_opts(&opts);
942
943 if (!data)
944 goto out;
945
946 BUG_ON(sb->s_type->fs_flags & FS_BINARY_MOUNTDATA);
947
948 rc = selinux_parse_opts_str(options, &opts);
949 if (rc)
950 goto out_err;
951
952 out:
953 rc = selinux_set_mnt_opts(sb, &opts);
954
955 out_err:
956 security_free_mnt_opts(&opts);
957 return rc;
958 }
959
960 static void selinux_write_opts(struct seq_file *m,
961 struct security_mnt_opts *opts)
962 {
963 int i;
964 char *prefix;
965
966 for (i = 0; i < opts->num_mnt_opts; i++) {
967 char *has_comma;
968
969 if (opts->mnt_opts[i])
970 has_comma = strchr(opts->mnt_opts[i], ',');
971 else
972 has_comma = NULL;
973
974 switch (opts->mnt_opts_flags[i]) {
975 case CONTEXT_MNT:
976 prefix = CONTEXT_STR;
977 break;
978 case FSCONTEXT_MNT:
979 prefix = FSCONTEXT_STR;
980 break;
981 case ROOTCONTEXT_MNT:
982 prefix = ROOTCONTEXT_STR;
983 break;
984 case DEFCONTEXT_MNT:
985 prefix = DEFCONTEXT_STR;
986 break;
987 case SE_SBLABELSUPP:
988 seq_putc(m, ',');
989 seq_puts(m, LABELSUPP_STR);
990 continue;
991 default:
992 BUG();
993 return;
994 };
995 /* we need a comma before each option */
996 seq_putc(m, ',');
997 seq_puts(m, prefix);
998 if (has_comma)
999 seq_putc(m, '\"');
1000 seq_puts(m, opts->mnt_opts[i]);
1001 if (has_comma)
1002 seq_putc(m, '\"');
1003 }
1004 }
1005
1006 static int selinux_sb_show_options(struct seq_file *m, struct super_block *sb)
1007 {
1008 struct security_mnt_opts opts;
1009 int rc;
1010
1011 rc = selinux_get_mnt_opts(sb, &opts);
1012 if (rc) {
1013 /* before policy load we may get EINVAL, don't show anything */
1014 if (rc == -EINVAL)
1015 rc = 0;
1016 return rc;
1017 }
1018
1019 selinux_write_opts(m, &opts);
1020
1021 security_free_mnt_opts(&opts);
1022
1023 return rc;
1024 }
1025
1026 static inline u16 inode_mode_to_security_class(umode_t mode)
1027 {
1028 switch (mode & S_IFMT) {
1029 case S_IFSOCK:
1030 return SECCLASS_SOCK_FILE;
1031 case S_IFLNK:
1032 return SECCLASS_LNK_FILE;
1033 case S_IFREG:
1034 return SECCLASS_FILE;
1035 case S_IFBLK:
1036 return SECCLASS_BLK_FILE;
1037 case S_IFDIR:
1038 return SECCLASS_DIR;
1039 case S_IFCHR:
1040 return SECCLASS_CHR_FILE;
1041 case S_IFIFO:
1042 return SECCLASS_FIFO_FILE;
1043
1044 }
1045
1046 return SECCLASS_FILE;
1047 }
1048
1049 static inline int default_protocol_stream(int protocol)
1050 {
1051 return (protocol == IPPROTO_IP || protocol == IPPROTO_TCP);
1052 }
1053
1054 static inline int default_protocol_dgram(int protocol)
1055 {
1056 return (protocol == IPPROTO_IP || protocol == IPPROTO_UDP);
1057 }
1058
1059 static inline u16 socket_type_to_security_class(int family, int type, int protocol)
1060 {
1061 switch (family) {
1062 case PF_UNIX:
1063 switch (type) {
1064 case SOCK_STREAM:
1065 case SOCK_SEQPACKET:
1066 return SECCLASS_UNIX_STREAM_SOCKET;
1067 case SOCK_DGRAM:
1068 return SECCLASS_UNIX_DGRAM_SOCKET;
1069 }
1070 break;
1071 case PF_INET:
1072 case PF_INET6:
1073 switch (type) {
1074 case SOCK_STREAM:
1075 if (default_protocol_stream(protocol))
1076 return SECCLASS_TCP_SOCKET;
1077 else
1078 return SECCLASS_RAWIP_SOCKET;
1079 case SOCK_DGRAM:
1080 if (default_protocol_dgram(protocol))
1081 return SECCLASS_UDP_SOCKET;
1082 else
1083 return SECCLASS_RAWIP_SOCKET;
1084 case SOCK_DCCP:
1085 return SECCLASS_DCCP_SOCKET;
1086 default:
1087 return SECCLASS_RAWIP_SOCKET;
1088 }
1089 break;
1090 case PF_NETLINK:
1091 switch (protocol) {
1092 case NETLINK_ROUTE:
1093 return SECCLASS_NETLINK_ROUTE_SOCKET;
1094 case NETLINK_FIREWALL:
1095 return SECCLASS_NETLINK_FIREWALL_SOCKET;
1096 case NETLINK_INET_DIAG:
1097 return SECCLASS_NETLINK_TCPDIAG_SOCKET;
1098 case NETLINK_NFLOG:
1099 return SECCLASS_NETLINK_NFLOG_SOCKET;
1100 case NETLINK_XFRM:
1101 return SECCLASS_NETLINK_XFRM_SOCKET;
1102 case NETLINK_SELINUX:
1103 return SECCLASS_NETLINK_SELINUX_SOCKET;
1104 case NETLINK_AUDIT:
1105 return SECCLASS_NETLINK_AUDIT_SOCKET;
1106 case NETLINK_IP6_FW:
1107 return SECCLASS_NETLINK_IP6FW_SOCKET;
1108 case NETLINK_DNRTMSG:
1109 return SECCLASS_NETLINK_DNRT_SOCKET;
1110 case NETLINK_KOBJECT_UEVENT:
1111 return SECCLASS_NETLINK_KOBJECT_UEVENT_SOCKET;
1112 default:
1113 return SECCLASS_NETLINK_SOCKET;
1114 }
1115 case PF_PACKET:
1116 return SECCLASS_PACKET_SOCKET;
1117 case PF_KEY:
1118 return SECCLASS_KEY_SOCKET;
1119 case PF_APPLETALK:
1120 return SECCLASS_APPLETALK_SOCKET;
1121 }
1122
1123 return SECCLASS_SOCKET;
1124 }
1125
1126 #ifdef CONFIG_PROC_FS
1127 static int selinux_proc_get_sid(struct dentry *dentry,
1128 u16 tclass,
1129 u32 *sid)
1130 {
1131 int rc;
1132 char *buffer, *path;
1133
1134 buffer = (char *)__get_free_page(GFP_KERNEL);
1135 if (!buffer)
1136 return -ENOMEM;
1137
1138 path = dentry_path_raw(dentry, buffer, PAGE_SIZE);
1139 if (IS_ERR(path))
1140 rc = PTR_ERR(path);
1141 else {
1142 /* each process gets a /proc/PID/ entry. Strip off the
1143 * PID part to get a valid selinux labeling.
1144 * e.g. /proc/1/net/rpc/nfs -> /net/rpc/nfs */
1145 while (path[1] >= '0' && path[1] <= '9') {
1146 path[1] = '/';
1147 path++;
1148 }
1149 rc = security_genfs_sid("proc", path, tclass, sid);
1150 }
1151 free_page((unsigned long)buffer);
1152 return rc;
1153 }
1154 #else
1155 static int selinux_proc_get_sid(struct dentry *dentry,
1156 u16 tclass,
1157 u32 *sid)
1158 {
1159 return -EINVAL;
1160 }
1161 #endif
1162
1163 /* The inode's security attributes must be initialized before first use. */
1164 static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dentry)
1165 {
1166 struct superblock_security_struct *sbsec = NULL;
1167 struct inode_security_struct *isec = inode->i_security;
1168 u32 sid;
1169 struct dentry *dentry;
1170 #define INITCONTEXTLEN 255
1171 char *context = NULL;
1172 unsigned len = 0;
1173 int rc = 0;
1174
1175 if (isec->initialized)
1176 goto out;
1177
1178 mutex_lock(&isec->lock);
1179 if (isec->initialized)
1180 goto out_unlock;
1181
1182 sbsec = inode->i_sb->s_security;
1183 if (!(sbsec->flags & SE_SBINITIALIZED)) {
1184 /* Defer initialization until selinux_complete_init,
1185 after the initial policy is loaded and the security
1186 server is ready to handle calls. */
1187 spin_lock(&sbsec->isec_lock);
1188 if (list_empty(&isec->list))
1189 list_add(&isec->list, &sbsec->isec_head);
1190 spin_unlock(&sbsec->isec_lock);
1191 goto out_unlock;
1192 }
1193
1194 switch (sbsec->behavior) {
1195 case SECURITY_FS_USE_XATTR:
1196 if (!inode->i_op->getxattr) {
1197 isec->sid = sbsec->def_sid;
1198 break;
1199 }
1200
1201 /* Need a dentry, since the xattr API requires one.
1202 Life would be simpler if we could just pass the inode. */
1203 if (opt_dentry) {
1204 /* Called from d_instantiate or d_splice_alias. */
1205 dentry = dget(opt_dentry);
1206 } else {
1207 /* Called from selinux_complete_init, try to find a dentry. */
1208 dentry = d_find_alias(inode);
1209 }
1210 if (!dentry) {
1211 /*
1212 * this is can be hit on boot when a file is accessed
1213 * before the policy is loaded. When we load policy we
1214 * may find inodes that have no dentry on the
1215 * sbsec->isec_head list. No reason to complain as these
1216 * will get fixed up the next time we go through
1217 * inode_doinit with a dentry, before these inodes could
1218 * be used again by userspace.
1219 */
1220 goto out_unlock;
1221 }
1222
1223 len = INITCONTEXTLEN;
1224 context = kmalloc(len+1, GFP_NOFS);
1225 if (!context) {
1226 rc = -ENOMEM;
1227 dput(dentry);
1228 goto out_unlock;
1229 }
1230 context[len] = '\0';
1231 rc = inode->i_op->getxattr(dentry, XATTR_NAME_SELINUX,
1232 context, len);
1233 if (rc == -ERANGE) {
1234 kfree(context);
1235
1236 /* Need a larger buffer. Query for the right size. */
1237 rc = inode->i_op->getxattr(dentry, XATTR_NAME_SELINUX,
1238 NULL, 0);
1239 if (rc < 0) {
1240 dput(dentry);
1241 goto out_unlock;
1242 }
1243 len = rc;
1244 context = kmalloc(len+1, GFP_NOFS);
1245 if (!context) {
1246 rc = -ENOMEM;
1247 dput(dentry);
1248 goto out_unlock;
1249 }
1250 context[len] = '\0';
1251 rc = inode->i_op->getxattr(dentry,
1252 XATTR_NAME_SELINUX,
1253 context, len);
1254 }
1255 dput(dentry);
1256 if (rc < 0) {
1257 if (rc != -ENODATA) {
1258 printk(KERN_WARNING "SELinux: %s: getxattr returned "
1259 "%d for dev=%s ino=%ld\n", __func__,
1260 -rc, inode->i_sb->s_id, inode->i_ino);
1261 kfree(context);
1262 goto out_unlock;
1263 }
1264 /* Map ENODATA to the default file SID */
1265 sid = sbsec->def_sid;
1266 rc = 0;
1267 } else {
1268 rc = security_context_to_sid_default(context, rc, &sid,
1269 sbsec->def_sid,
1270 GFP_NOFS);
1271 if (rc) {
1272 char *dev = inode->i_sb->s_id;
1273 unsigned long ino = inode->i_ino;
1274
1275 if (rc == -EINVAL) {
1276 if (printk_ratelimit())
1277 printk(KERN_NOTICE "SELinux: inode=%lu on dev=%s was found to have an invalid "
1278 "context=%s. This indicates you may need to relabel the inode or the "
1279 "filesystem in question.\n", ino, dev, context);
1280 } else {
1281 printk(KERN_WARNING "SELinux: %s: context_to_sid(%s) "
1282 "returned %d for dev=%s ino=%ld\n",
1283 __func__, context, -rc, dev, ino);
1284 }
1285 kfree(context);
1286 /* Leave with the unlabeled SID */
1287 rc = 0;
1288 break;
1289 }
1290 }
1291 kfree(context);
1292 isec->sid = sid;
1293 break;
1294 case SECURITY_FS_USE_TASK:
1295 isec->sid = isec->task_sid;
1296 break;
1297 case SECURITY_FS_USE_TRANS:
1298 /* Default to the fs SID. */
1299 isec->sid = sbsec->sid;
1300
1301 /* Try to obtain a transition SID. */
1302 isec->sclass = inode_mode_to_security_class(inode->i_mode);
1303 rc = security_transition_sid(isec->task_sid, sbsec->sid,
1304 isec->sclass, NULL, &sid);
1305 if (rc)
1306 goto out_unlock;
1307 isec->sid = sid;
1308 break;
1309 case SECURITY_FS_USE_MNTPOINT:
1310 isec->sid = sbsec->mntpoint_sid;
1311 break;
1312 default:
1313 /* Default to the fs superblock SID. */
1314 isec->sid = sbsec->sid;
1315
1316 if ((sbsec->flags & SE_SBPROC) && !S_ISLNK(inode->i_mode)) {
1317 if (opt_dentry) {
1318 isec->sclass = inode_mode_to_security_class(inode->i_mode);
1319 rc = selinux_proc_get_sid(opt_dentry,
1320 isec->sclass,
1321 &sid);
1322 if (rc)
1323 goto out_unlock;
1324 isec->sid = sid;
1325 }
1326 }
1327 break;
1328 }
1329
1330 isec->initialized = 1;
1331
1332 out_unlock:
1333 mutex_unlock(&isec->lock);
1334 out:
1335 if (isec->sclass == SECCLASS_FILE)
1336 isec->sclass = inode_mode_to_security_class(inode->i_mode);
1337 return rc;
1338 }
1339
1340 /* Convert a Linux signal to an access vector. */
1341 static inline u32 signal_to_av(int sig)
1342 {
1343 u32 perm = 0;
1344
1345 switch (sig) {
1346 case SIGCHLD:
1347 /* Commonly granted from child to parent. */
1348 perm = PROCESS__SIGCHLD;
1349 break;
1350 case SIGKILL:
1351 /* Cannot be caught or ignored */
1352 perm = PROCESS__SIGKILL;
1353 break;
1354 case SIGSTOP:
1355 /* Cannot be caught or ignored */
1356 perm = PROCESS__SIGSTOP;
1357 break;
1358 default:
1359 /* All other signals. */
1360 perm = PROCESS__SIGNAL;
1361 break;
1362 }
1363
1364 return perm;
1365 }
1366
1367 /*
1368 * Check permission between a pair of credentials
1369 * fork check, ptrace check, etc.
1370 */
1371 static int cred_has_perm(const struct cred *actor,
1372 const struct cred *target,
1373 u32 perms)
1374 {
1375 u32 asid = cred_sid(actor), tsid = cred_sid(target);
1376
1377 return avc_has_perm(asid, tsid, SECCLASS_PROCESS, perms, NULL);
1378 }
1379
1380 /*
1381 * Check permission between a pair of tasks, e.g. signal checks,
1382 * fork check, ptrace check, etc.
1383 * tsk1 is the actor and tsk2 is the target
1384 * - this uses the default subjective creds of tsk1
1385 */
1386 static int task_has_perm(const struct task_struct *tsk1,
1387 const struct task_struct *tsk2,
1388 u32 perms)
1389 {
1390 const struct task_security_struct *__tsec1, *__tsec2;
1391 u32 sid1, sid2;
1392
1393 rcu_read_lock();
1394 __tsec1 = __task_cred(tsk1)->security; sid1 = __tsec1->sid;
1395 __tsec2 = __task_cred(tsk2)->security; sid2 = __tsec2->sid;
1396 rcu_read_unlock();
1397 return avc_has_perm(sid1, sid2, SECCLASS_PROCESS, perms, NULL);
1398 }
1399
1400 /*
1401 * Check permission between current and another task, e.g. signal checks,
1402 * fork check, ptrace check, etc.
1403 * current is the actor and tsk2 is the target
1404 * - this uses current's subjective creds
1405 */
1406 static int current_has_perm(const struct task_struct *tsk,
1407 u32 perms)
1408 {
1409 u32 sid, tsid;
1410
1411 sid = current_sid();
1412 tsid = task_sid(tsk);
1413 return avc_has_perm(sid, tsid, SECCLASS_PROCESS, perms, NULL);
1414 }
1415
1416 #if CAP_LAST_CAP > 63
1417 #error Fix SELinux to handle capabilities > 63.
1418 #endif
1419
1420 /* Check whether a task is allowed to use a capability. */
1421 static int task_has_capability(struct task_struct *tsk,
1422 const struct cred *cred,
1423 int cap, int audit)
1424 {
1425 struct common_audit_data ad;
1426 struct av_decision avd;
1427 u16 sclass;
1428 u32 sid = cred_sid(cred);
1429 u32 av = CAP_TO_MASK(cap);
1430 int rc;
1431
1432 COMMON_AUDIT_DATA_INIT(&ad, CAP);
1433 ad.tsk = tsk;
1434 ad.u.cap = cap;
1435
1436 switch (CAP_TO_INDEX(cap)) {
1437 case 0:
1438 sclass = SECCLASS_CAPABILITY;
1439 break;
1440 case 1:
1441 sclass = SECCLASS_CAPABILITY2;
1442 break;
1443 default:
1444 printk(KERN_ERR
1445 "SELinux: out of range capability %d\n", cap);
1446 BUG();
1447 return -EINVAL;
1448 }
1449
1450 rc = avc_has_perm_noaudit(sid, sid, sclass, av, 0, &avd);
1451 if (audit == SECURITY_CAP_AUDIT) {
1452 int rc2 = avc_audit(sid, sid, sclass, av, &avd, rc, &ad, 0);
1453 if (rc2)
1454 return rc2;
1455 }
1456 return rc;
1457 }
1458
1459 /* Check whether a task is allowed to use a system operation. */
1460 static int task_has_system(struct task_struct *tsk,
1461 u32 perms)
1462 {
1463 u32 sid = task_sid(tsk);
1464
1465 return avc_has_perm(sid, SECINITSID_KERNEL,
1466 SECCLASS_SYSTEM, perms, NULL);
1467 }
1468
1469 /* Check whether a task has a particular permission to an inode.
1470 The 'adp' parameter is optional and allows other audit
1471 data to be passed (e.g. the dentry). */
1472 static int inode_has_perm(const struct cred *cred,
1473 struct inode *inode,
1474 u32 perms,
1475 struct common_audit_data *adp,
1476 unsigned flags)
1477 {
1478 struct inode_security_struct *isec;
1479 u32 sid;
1480
1481 validate_creds(cred);
1482
1483 if (unlikely(IS_PRIVATE(inode)))
1484 return 0;
1485
1486 sid = cred_sid(cred);
1487 isec = inode->i_security;
1488
1489 return avc_has_perm_flags(sid, isec->sid, isec->sclass, perms, adp, flags);
1490 }
1491
1492 static int inode_has_perm_noadp(const struct cred *cred,
1493 struct inode *inode,
1494 u32 perms,
1495 unsigned flags)
1496 {
1497 struct common_audit_data ad;
1498
1499 COMMON_AUDIT_DATA_INIT(&ad, INODE);
1500 ad.u.inode = inode;
1501 return inode_has_perm(cred, inode, perms, &ad, flags);
1502 }
1503
1504 /* Same as inode_has_perm, but pass explicit audit data containing
1505 the dentry to help the auditing code to more easily generate the
1506 pathname if needed. */
1507 static inline int dentry_has_perm(const struct cred *cred,
1508 struct dentry *dentry,
1509 u32 av)
1510 {
1511 struct inode *inode = dentry->d_inode;
1512 struct common_audit_data ad;
1513
1514 COMMON_AUDIT_DATA_INIT(&ad, DENTRY);
1515 ad.u.dentry = dentry;
1516 return inode_has_perm(cred, inode, av, &ad, 0);
1517 }
1518
1519 /* Same as inode_has_perm, but pass explicit audit data containing
1520 the path to help the auditing code to more easily generate the
1521 pathname if needed. */
1522 static inline int path_has_perm(const struct cred *cred,
1523 struct path *path,
1524 u32 av)
1525 {
1526 struct inode *inode = path->dentry->d_inode;
1527 struct common_audit_data ad;
1528
1529 COMMON_AUDIT_DATA_INIT(&ad, PATH);
1530 ad.u.path = *path;
1531 return inode_has_perm(cred, inode, av, &ad, 0);
1532 }
1533
1534 /* Check whether a task can use an open file descriptor to
1535 access an inode in a given way. Check access to the
1536 descriptor itself, and then use dentry_has_perm to
1537 check a particular permission to the file.
1538 Access to the descriptor is implicitly granted if it
1539 has the same SID as the process. If av is zero, then
1540 access to the file is not checked, e.g. for cases
1541 where only the descriptor is affected like seek. */
1542 static int file_has_perm(const struct cred *cred,
1543 struct file *file,
1544 u32 av)
1545 {
1546 struct file_security_struct *fsec = file->f_security;
1547 struct inode *inode = file->f_path.dentry->d_inode;
1548 struct common_audit_data ad;
1549 u32 sid = cred_sid(cred);
1550 int rc;
1551
1552 COMMON_AUDIT_DATA_INIT(&ad, PATH);
1553 ad.u.path = file->f_path;
1554
1555 if (sid != fsec->sid) {
1556 rc = avc_has_perm(sid, fsec->sid,
1557 SECCLASS_FD,
1558 FD__USE,
1559 &ad);
1560 if (rc)
1561 goto out;
1562 }
1563
1564 /* av is zero if only checking access to the descriptor. */
1565 rc = 0;
1566 if (av)
1567 rc = inode_has_perm(cred, inode, av, &ad, 0);
1568
1569 out:
1570 return rc;
1571 }
1572
1573 /* Check whether a task can create a file. */
1574 static int may_create(struct inode *dir,
1575 struct dentry *dentry,
1576 u16 tclass)
1577 {
1578 const struct task_security_struct *tsec = current_security();
1579 struct inode_security_struct *dsec;
1580 struct superblock_security_struct *sbsec;
1581 u32 sid, newsid;
1582 struct common_audit_data ad;
1583 int rc;
1584
1585 dsec = dir->i_security;
1586 sbsec = dir->i_sb->s_security;
1587
1588 sid = tsec->sid;
1589 newsid = tsec->create_sid;
1590
1591 COMMON_AUDIT_DATA_INIT(&ad, DENTRY);
1592 ad.u.dentry = dentry;
1593
1594 rc = avc_has_perm(sid, dsec->sid, SECCLASS_DIR,
1595 DIR__ADD_NAME | DIR__SEARCH,
1596 &ad);
1597 if (rc)
1598 return rc;
1599
1600 if (!newsid || !(sbsec->flags & SE_SBLABELSUPP)) {
1601 rc = security_transition_sid(sid, dsec->sid, tclass,
1602 &dentry->d_name, &newsid);
1603 if (rc)
1604 return rc;
1605 }
1606
1607 rc = avc_has_perm(sid, newsid, tclass, FILE__CREATE, &ad);
1608 if (rc)
1609 return rc;
1610
1611 return avc_has_perm(newsid, sbsec->sid,
1612 SECCLASS_FILESYSTEM,
1613 FILESYSTEM__ASSOCIATE, &ad);
1614 }
1615
1616 /* Check whether a task can create a key. */
1617 static int may_create_key(u32 ksid,
1618 struct task_struct *ctx)
1619 {
1620 u32 sid = task_sid(ctx);
1621
1622 return avc_has_perm(sid, ksid, SECCLASS_KEY, KEY__CREATE, NULL);
1623 }
1624
1625 #define MAY_LINK 0
1626 #define MAY_UNLINK 1
1627 #define MAY_RMDIR 2
1628
1629 /* Check whether a task can link, unlink, or rmdir a file/directory. */
1630 static int may_link(struct inode *dir,
1631 struct dentry *dentry,
1632 int kind)
1633
1634 {
1635 struct inode_security_struct *dsec, *isec;
1636 struct common_audit_data ad;
1637 u32 sid = current_sid();
1638 u32 av;
1639 int rc;
1640
1641 dsec = dir->i_security;
1642 isec = dentry->d_inode->i_security;
1643
1644 COMMON_AUDIT_DATA_INIT(&ad, DENTRY);
1645 ad.u.dentry = dentry;
1646
1647 av = DIR__SEARCH;
1648 av |= (kind ? DIR__REMOVE_NAME : DIR__ADD_NAME);
1649 rc = avc_has_perm(sid, dsec->sid, SECCLASS_DIR, av, &ad);
1650 if (rc)
1651 return rc;
1652
1653 switch (kind) {
1654 case MAY_LINK:
1655 av = FILE__LINK;
1656 break;
1657 case MAY_UNLINK:
1658 av = FILE__UNLINK;
1659 break;
1660 case MAY_RMDIR:
1661 av = DIR__RMDIR;
1662 break;
1663 default:
1664 printk(KERN_WARNING "SELinux: %s: unrecognized kind %d\n",
1665 __func__, kind);
1666 return 0;
1667 }
1668
1669 rc = avc_has_perm(sid, isec->sid, isec->sclass, av, &ad);
1670 return rc;
1671 }
1672
1673 static inline int may_rename(struct inode *old_dir,
1674 struct dentry *old_dentry,
1675 struct inode *new_dir,
1676 struct dentry *new_dentry)
1677 {
1678 struct inode_security_struct *old_dsec, *new_dsec, *old_isec, *new_isec;
1679 struct common_audit_data ad;
1680 u32 sid = current_sid();
1681 u32 av;
1682 int old_is_dir, new_is_dir;
1683 int rc;
1684
1685 old_dsec = old_dir->i_security;
1686 old_isec = old_dentry->d_inode->i_security;
1687 old_is_dir = S_ISDIR(old_dentry->d_inode->i_mode);
1688 new_dsec = new_dir->i_security;
1689
1690 COMMON_AUDIT_DATA_INIT(&ad, DENTRY);
1691
1692 ad.u.dentry = old_dentry;
1693 rc = avc_has_perm(sid, old_dsec->sid, SECCLASS_DIR,
1694 DIR__REMOVE_NAME | DIR__SEARCH, &ad);
1695 if (rc)
1696 return rc;
1697 rc = avc_has_perm(sid, old_isec->sid,
1698 old_isec->sclass, FILE__RENAME, &ad);
1699 if (rc)
1700 return rc;
1701 if (old_is_dir && new_dir != old_dir) {
1702 rc = avc_has_perm(sid, old_isec->sid,
1703 old_isec->sclass, DIR__REPARENT, &ad);
1704 if (rc)
1705 return rc;
1706 }
1707
1708 ad.u.dentry = new_dentry;
1709 av = DIR__ADD_NAME | DIR__SEARCH;
1710 if (new_dentry->d_inode)
1711 av |= DIR__REMOVE_NAME;
1712 rc = avc_has_perm(sid, new_dsec->sid, SECCLASS_DIR, av, &ad);
1713 if (rc)
1714 return rc;
1715 if (new_dentry->d_inode) {
1716 new_isec = new_dentry->d_inode->i_security;
1717 new_is_dir = S_ISDIR(new_dentry->d_inode->i_mode);
1718 rc = avc_has_perm(sid, new_isec->sid,
1719 new_isec->sclass,
1720 (new_is_dir ? DIR__RMDIR : FILE__UNLINK), &ad);
1721 if (rc)
1722 return rc;
1723 }
1724
1725 return 0;
1726 }
1727
1728 /* Check whether a task can perform a filesystem operation. */
1729 static int superblock_has_perm(const struct cred *cred,
1730 struct super_block *sb,
1731 u32 perms,
1732 struct common_audit_data *ad)
1733 {
1734 struct superblock_security_struct *sbsec;
1735 u32 sid = cred_sid(cred);
1736
1737 sbsec = sb->s_security;
1738 return avc_has_perm(sid, sbsec->sid, SECCLASS_FILESYSTEM, perms, ad);
1739 }
1740
1741 /* Convert a Linux mode and permission mask to an access vector. */
1742 static inline u32 file_mask_to_av(int mode, int mask)
1743 {
1744 u32 av = 0;
1745
1746 if ((mode & S_IFMT) != S_IFDIR) {
1747 if (mask & MAY_EXEC)
1748 av |= FILE__EXECUTE;
1749 if (mask & MAY_READ)
1750 av |= FILE__READ;
1751
1752 if (mask & MAY_APPEND)
1753 av |= FILE__APPEND;
1754 else if (mask & MAY_WRITE)
1755 av |= FILE__WRITE;
1756
1757 } else {
1758 if (mask & MAY_EXEC)
1759 av |= DIR__SEARCH;
1760 if (mask & MAY_WRITE)
1761 av |= DIR__WRITE;
1762 if (mask & MAY_READ)
1763 av |= DIR__READ;
1764 }
1765
1766 return av;
1767 }
1768
1769 /* Convert a Linux file to an access vector. */
1770 static inline u32 file_to_av(struct file *file)
1771 {
1772 u32 av = 0;
1773
1774 if (file->f_mode & FMODE_READ)
1775 av |= FILE__READ;
1776 if (file->f_mode & FMODE_WRITE) {
1777 if (file->f_flags & O_APPEND)
1778 av |= FILE__APPEND;
1779 else
1780 av |= FILE__WRITE;
1781 }
1782 if (!av) {
1783 /*
1784 * Special file opened with flags 3 for ioctl-only use.
1785 */
1786 av = FILE__IOCTL;
1787 }
1788
1789 return av;
1790 }
1791
1792 /*
1793 * Convert a file to an access vector and include the correct open
1794 * open permission.
1795 */
1796 static inline u32 open_file_to_av(struct file *file)
1797 {
1798 u32 av = file_to_av(file);
1799
1800 if (selinux_policycap_openperm)
1801 av |= FILE__OPEN;
1802
1803 return av;
1804 }
1805
1806 /* Hook functions begin here. */
1807
1808 static int selinux_ptrace_access_check(struct task_struct *child,
1809 unsigned int mode)
1810 {
1811 int rc;
1812
1813 rc = cap_ptrace_access_check(child, mode);
1814 if (rc)
1815 return rc;
1816
1817 if (mode == PTRACE_MODE_READ) {
1818 u32 sid = current_sid();
1819 u32 csid = task_sid(child);
1820 return avc_has_perm(sid, csid, SECCLASS_FILE, FILE__READ, NULL);
1821 }
1822
1823 return current_has_perm(child, PROCESS__PTRACE);
1824 }
1825
1826 static int selinux_ptrace_traceme(struct task_struct *parent)
1827 {
1828 int rc;
1829
1830 rc = cap_ptrace_traceme(parent);
1831 if (rc)
1832 return rc;
1833
1834 return task_has_perm(parent, current, PROCESS__PTRACE);
1835 }
1836
1837 static int selinux_capget(struct task_struct *target, kernel_cap_t *effective,
1838 kernel_cap_t *inheritable, kernel_cap_t *permitted)
1839 {
1840 int error;
1841
1842 error = current_has_perm(target, PROCESS__GETCAP);
1843 if (error)
1844 return error;
1845
1846 return cap_capget(target, effective, inheritable, permitted);
1847 }
1848
1849 static int selinux_capset(struct cred *new, const struct cred *old,
1850 const kernel_cap_t *effective,
1851 const kernel_cap_t *inheritable,
1852 const kernel_cap_t *permitted)
1853 {
1854 int error;
1855
1856 error = cap_capset(new, old,
1857 effective, inheritable, permitted);
1858 if (error)
1859 return error;
1860
1861 return cred_has_perm(old, new, PROCESS__SETCAP);
1862 }
1863
1864 /*
1865 * (This comment used to live with the selinux_task_setuid hook,
1866 * which was removed).
1867 *
1868 * Since setuid only affects the current process, and since the SELinux
1869 * controls are not based on the Linux identity attributes, SELinux does not
1870 * need to control this operation. However, SELinux does control the use of
1871 * the CAP_SETUID and CAP_SETGID capabilities using the capable hook.
1872 */
1873
1874 static int selinux_capable(struct task_struct *tsk, const struct cred *cred,
1875 struct user_namespace *ns, int cap, int audit)
1876 {
1877 int rc;
1878
1879 rc = cap_capable(tsk, cred, ns, cap, audit);
1880 if (rc)
1881 return rc;
1882
1883 return task_has_capability(tsk, cred, cap, audit);
1884 }
1885
1886 static int selinux_quotactl(int cmds, int type, int id, struct super_block *sb)
1887 {
1888 const struct cred *cred = current_cred();
1889 int rc = 0;
1890
1891 if (!sb)
1892 return 0;
1893
1894 switch (cmds) {
1895 case Q_SYNC:
1896 case Q_QUOTAON:
1897 case Q_QUOTAOFF:
1898 case Q_SETINFO:
1899 case Q_SETQUOTA:
1900 rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAMOD, NULL);
1901 break;
1902 case Q_GETFMT:
1903 case Q_GETINFO:
1904 case Q_GETQUOTA:
1905 rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAGET, NULL);
1906 break;
1907 default:
1908 rc = 0; /* let the kernel handle invalid cmds */
1909 break;
1910 }
1911 return rc;
1912 }
1913
1914 static int selinux_quota_on(struct dentry *dentry)
1915 {
1916 const struct cred *cred = current_cred();
1917
1918 return dentry_has_perm(cred, dentry, FILE__QUOTAON);
1919 }
1920
1921 static int selinux_syslog(int type)
1922 {
1923 int rc;
1924
1925 switch (type) {
1926 case SYSLOG_ACTION_READ_ALL: /* Read last kernel messages */
1927 case SYSLOG_ACTION_SIZE_BUFFER: /* Return size of the log buffer */
1928 rc = task_has_system(current, SYSTEM__SYSLOG_READ);
1929 break;
1930 case SYSLOG_ACTION_CONSOLE_OFF: /* Disable logging to console */
1931 case SYSLOG_ACTION_CONSOLE_ON: /* Enable logging to console */
1932 /* Set level of messages printed to console */
1933 case SYSLOG_ACTION_CONSOLE_LEVEL:
1934 rc = task_has_system(current, SYSTEM__SYSLOG_CONSOLE);
1935 break;
1936 case SYSLOG_ACTION_CLOSE: /* Close log */
1937 case SYSLOG_ACTION_OPEN: /* Open log */
1938 case SYSLOG_ACTION_READ: /* Read from log */
1939 case SYSLOG_ACTION_READ_CLEAR: /* Read/clear last kernel messages */
1940 case SYSLOG_ACTION_CLEAR: /* Clear ring buffer */
1941 default:
1942 rc = task_has_system(current, SYSTEM__SYSLOG_MOD);
1943 break;
1944 }
1945 return rc;
1946 }
1947
1948 /*
1949 * Check that a process has enough memory to allocate a new virtual
1950 * mapping. 0 means there is enough memory for the allocation to
1951 * succeed and -ENOMEM implies there is not.
1952 *
1953 * Do not audit the selinux permission check, as this is applied to all
1954 * processes that allocate mappings.
1955 */
1956 static int selinux_vm_enough_memory(struct mm_struct *mm, long pages)
1957 {
1958 int rc, cap_sys_admin = 0;
1959
1960 rc = selinux_capable(current, current_cred(),
1961 &init_user_ns, CAP_SYS_ADMIN,
1962 SECURITY_CAP_NOAUDIT);
1963 if (rc == 0)
1964 cap_sys_admin = 1;
1965
1966 return __vm_enough_memory(mm, pages, cap_sys_admin);
1967 }
1968
1969 /* binprm security operations */
1970
1971 static int selinux_bprm_set_creds(struct linux_binprm *bprm)
1972 {
1973 const struct task_security_struct *old_tsec;
1974 struct task_security_struct *new_tsec;
1975 struct inode_security_struct *isec;
1976 struct common_audit_data ad;
1977 struct inode *inode = bprm->file->f_path.dentry->d_inode;
1978 int rc;
1979
1980 rc = cap_bprm_set_creds(bprm);
1981 if (rc)
1982 return rc;
1983
1984 /* SELinux context only depends on initial program or script and not
1985 * the script interpreter */
1986 if (bprm->cred_prepared)
1987 return 0;
1988
1989 old_tsec = current_security();
1990 new_tsec = bprm->cred->security;
1991 isec = inode->i_security;
1992
1993 /* Default to the current task SID. */
1994 new_tsec->sid = old_tsec->sid;
1995 new_tsec->osid = old_tsec->sid;
1996
1997 /* Reset fs, key, and sock SIDs on execve. */
1998 new_tsec->create_sid = 0;
1999 new_tsec->keycreate_sid = 0;
2000 new_tsec->sockcreate_sid = 0;
2001
2002 if (old_tsec->exec_sid) {
2003 new_tsec->sid = old_tsec->exec_sid;
2004 /* Reset exec SID on execve. */
2005 new_tsec->exec_sid = 0;
2006 } else {
2007 /* Check for a default transition on this program. */
2008 rc = security_transition_sid(old_tsec->sid, isec->sid,
2009 SECCLASS_PROCESS, NULL,
2010 &new_tsec->sid);
2011 if (rc)
2012 return rc;
2013 }
2014
2015 COMMON_AUDIT_DATA_INIT(&ad, PATH);
2016 ad.u.path = bprm->file->f_path;
2017
2018 if (bprm->file->f_path.mnt->mnt_flags & MNT_NOSUID)
2019 new_tsec->sid = old_tsec->sid;
2020
2021 if (new_tsec->sid == old_tsec->sid) {
2022 rc = avc_has_perm(old_tsec->sid, isec->sid,
2023 SECCLASS_FILE, FILE__EXECUTE_NO_TRANS, &ad);
2024 if (rc)
2025 return rc;
2026 } else {
2027 /* Check permissions for the transition. */
2028 rc = avc_has_perm(old_tsec->sid, new_tsec->sid,
2029 SECCLASS_PROCESS, PROCESS__TRANSITION, &ad);
2030 if (rc)
2031 return rc;
2032
2033 rc = avc_has_perm(new_tsec->sid, isec->sid,
2034 SECCLASS_FILE, FILE__ENTRYPOINT, &ad);
2035 if (rc)
2036 return rc;
2037
2038 /* Check for shared state */
2039 if (bprm->unsafe & LSM_UNSAFE_SHARE) {
2040 rc = avc_has_perm(old_tsec->sid, new_tsec->sid,
2041 SECCLASS_PROCESS, PROCESS__SHARE,
2042 NULL);
2043 if (rc)
2044 return -EPERM;
2045 }
2046
2047 /* Make sure that anyone attempting to ptrace over a task that
2048 * changes its SID has the appropriate permit */
2049 if (bprm->unsafe &
2050 (LSM_UNSAFE_PTRACE | LSM_UNSAFE_PTRACE_CAP)) {
2051 struct task_struct *tracer;
2052 struct task_security_struct *sec;
2053 u32 ptsid = 0;
2054
2055 rcu_read_lock();
2056 tracer = ptrace_parent(current);
2057 if (likely(tracer != NULL)) {
2058 sec = __task_cred(tracer)->security;
2059 ptsid = sec->sid;
2060 }
2061 rcu_read_unlock();
2062
2063 if (ptsid != 0) {
2064 rc = avc_has_perm(ptsid, new_tsec->sid,
2065 SECCLASS_PROCESS,
2066 PROCESS__PTRACE, NULL);
2067 if (rc)
2068 return -EPERM;
2069 }
2070 }
2071
2072 /* Clear any possibly unsafe personality bits on exec: */
2073 bprm->per_clear |= PER_CLEAR_ON_SETID;
2074 }
2075
2076 return 0;
2077 }
2078
2079 static int selinux_bprm_secureexec(struct linux_binprm *bprm)
2080 {
2081 const struct task_security_struct *tsec = current_security();
2082 u32 sid, osid;
2083 int atsecure = 0;
2084
2085 sid = tsec->sid;
2086 osid = tsec->osid;
2087
2088 if (osid != sid) {
2089 /* Enable secure mode for SIDs transitions unless
2090 the noatsecure permission is granted between
2091 the two SIDs, i.e. ahp returns 0. */
2092 atsecure = avc_has_perm(osid, sid,
2093 SECCLASS_PROCESS,
2094 PROCESS__NOATSECURE, NULL);
2095 }
2096
2097 return (atsecure || cap_bprm_secureexec(bprm));
2098 }
2099
2100 extern struct vfsmount *selinuxfs_mount;
2101 extern struct dentry *selinux_null;
2102
2103 /* Derived from fs/exec.c:flush_old_files. */
2104 static inline void flush_unauthorized_files(const struct cred *cred,
2105 struct files_struct *files)
2106 {
2107 struct common_audit_data ad;
2108 struct file *file, *devnull = NULL;
2109 struct tty_struct *tty;
2110 struct fdtable *fdt;
2111 long j = -1;
2112 int drop_tty = 0;
2113
2114 tty = get_current_tty();
2115 if (tty) {
2116 spin_lock(&tty_files_lock);
2117 if (!list_empty(&tty->tty_files)) {
2118 struct tty_file_private *file_priv;
2119 struct inode *inode;
2120
2121 /* Revalidate access to controlling tty.
2122 Use inode_has_perm on the tty inode directly rather
2123 than using file_has_perm, as this particular open
2124 file may belong to another process and we are only
2125 interested in the inode-based check here. */
2126 file_priv = list_first_entry(&tty->tty_files,
2127 struct tty_file_private, list);
2128 file = file_priv->file;
2129 inode = file->f_path.dentry->d_inode;
2130 if (inode_has_perm_noadp(cred, inode,
2131 FILE__READ | FILE__WRITE, 0)) {
2132 drop_tty = 1;
2133 }
2134 }
2135 spin_unlock(&tty_files_lock);
2136 tty_kref_put(tty);
2137 }
2138 /* Reset controlling tty. */
2139 if (drop_tty)
2140 no_tty();
2141
2142 /* Revalidate access to inherited open files. */
2143
2144 COMMON_AUDIT_DATA_INIT(&ad, INODE);
2145
2146 spin_lock(&files->file_lock);
2147 for (;;) {
2148 unsigned long set, i;
2149 int fd;
2150
2151 j++;
2152 i = j * __NFDBITS;
2153 fdt = files_fdtable(files);
2154 if (i >= fdt->max_fds)
2155 break;
2156 set = fdt->open_fds->fds_bits[j];
2157 if (!set)
2158 continue;
2159 spin_unlock(&files->file_lock);
2160 for ( ; set ; i++, set >>= 1) {
2161 if (set & 1) {
2162 file = fget(i);
2163 if (!file)
2164 continue;
2165 if (file_has_perm(cred,
2166 file,
2167 file_to_av(file))) {
2168 sys_close(i);
2169 fd = get_unused_fd();
2170 if (fd != i) {
2171 if (fd >= 0)
2172 put_unused_fd(fd);
2173 fput(file);
2174 continue;
2175 }
2176 if (devnull) {
2177 get_file(devnull);
2178 } else {
2179 devnull = dentry_open(
2180 dget(selinux_null),
2181 mntget(selinuxfs_mount),
2182 O_RDWR, cred);
2183 if (IS_ERR(devnull)) {
2184 devnull = NULL;
2185 put_unused_fd(fd);
2186 fput(file);
2187 continue;
2188 }
2189 }
2190 fd_install(fd, devnull);
2191 }
2192 fput(file);
2193 }
2194 }
2195 spin_lock(&files->file_lock);
2196
2197 }
2198 spin_unlock(&files->file_lock);
2199 }
2200
2201 /*
2202 * Prepare a process for imminent new credential changes due to exec
2203 */
2204 static void selinux_bprm_committing_creds(struct linux_binprm *bprm)
2205 {
2206 struct task_security_struct *new_tsec;
2207 struct rlimit *rlim, *initrlim;
2208 int rc, i;
2209
2210 new_tsec = bprm->cred->security;
2211 if (new_tsec->sid == new_tsec->osid)
2212 return;
2213
2214 /* Close files for which the new task SID is not authorized. */
2215 flush_unauthorized_files(bprm->cred, current->files);
2216
2217 /* Always clear parent death signal on SID transitions. */
2218 current->pdeath_signal = 0;
2219
2220 /* Check whether the new SID can inherit resource limits from the old
2221 * SID. If not, reset all soft limits to the lower of the current
2222 * task's hard limit and the init task's soft limit.
2223 *
2224 * Note that the setting of hard limits (even to lower them) can be
2225 * controlled by the setrlimit check. The inclusion of the init task's
2226 * soft limit into the computation is to avoid resetting soft limits
2227 * higher than the default soft limit for cases where the default is
2228 * lower than the hard limit, e.g. RLIMIT_CORE or RLIMIT_STACK.
2229 */
2230 rc = avc_has_perm(new_tsec->osid, new_tsec->sid, SECCLASS_PROCESS,
2231 PROCESS__RLIMITINH, NULL);
2232 if (rc) {
2233 /* protect against do_prlimit() */
2234 task_lock(current);
2235 for (i = 0; i < RLIM_NLIMITS; i++) {
2236 rlim = current->signal->rlim + i;
2237 initrlim = init_task.signal->rlim + i;
2238 rlim->rlim_cur = min(rlim->rlim_max, initrlim->rlim_cur);
2239 }
2240 task_unlock(current);
2241 update_rlimit_cpu(current, rlimit(RLIMIT_CPU));
2242 }
2243 }
2244
2245 /*
2246 * Clean up the process immediately after the installation of new credentials
2247 * due to exec
2248 */
2249 static void selinux_bprm_committed_creds(struct linux_binprm *bprm)
2250 {
2251 const struct task_security_struct *tsec = current_security();
2252 struct itimerval itimer;
2253 u32 osid, sid;
2254 int rc, i;
2255
2256 osid = tsec->osid;
2257 sid = tsec->sid;
2258
2259 if (sid == osid)
2260 return;
2261
2262 /* Check whether the new SID can inherit signal state from the old SID.
2263 * If not, clear itimers to avoid subsequent signal generation and
2264 * flush and unblock signals.
2265 *
2266 * This must occur _after_ the task SID has been updated so that any
2267 * kill done after the flush will be checked against the new SID.
2268 */
2269 rc = avc_has_perm(osid, sid, SECCLASS_PROCESS, PROCESS__SIGINH, NULL);
2270 if (rc) {
2271 memset(&itimer, 0, sizeof itimer);
2272 for (i = 0; i < 3; i++)
2273 do_setitimer(i, &itimer, NULL);
2274 spin_lock_irq(&current->sighand->siglock);
2275 if (!(current->signal->flags & SIGNAL_GROUP_EXIT)) {
2276 __flush_signals(current);
2277 flush_signal_handlers(current, 1);
2278 sigemptyset(&current->blocked);
2279 }
2280 spin_unlock_irq(&current->sighand->siglock);
2281 }
2282
2283 /* Wake up the parent if it is waiting so that it can recheck
2284 * wait permission to the new task SID. */
2285 read_lock(&tasklist_lock);
2286 __wake_up_parent(current, current->real_parent);
2287 read_unlock(&tasklist_lock);
2288 }
2289
2290 /* superblock security operations */
2291
2292 static int selinux_sb_alloc_security(struct super_block *sb)
2293 {
2294 return superblock_alloc_security(sb);
2295 }
2296
2297 static void selinux_sb_free_security(struct super_block *sb)
2298 {
2299 superblock_free_security(sb);
2300 }
2301
2302 static inline int match_prefix(char *prefix, int plen, char *option, int olen)
2303 {
2304 if (plen > olen)
2305 return 0;
2306
2307 return !memcmp(prefix, option, plen);
2308 }
2309
2310 static inline int selinux_option(char *option, int len)
2311 {
2312 return (match_prefix(CONTEXT_STR, sizeof(CONTEXT_STR)-1, option, len) ||
2313 match_prefix(FSCONTEXT_STR, sizeof(FSCONTEXT_STR)-1, option, len) ||
2314 match_prefix(DEFCONTEXT_STR, sizeof(DEFCONTEXT_STR)-1, option, len) ||
2315 match_prefix(ROOTCONTEXT_STR, sizeof(ROOTCONTEXT_STR)-1, option, len) ||
2316 match_prefix(LABELSUPP_STR, sizeof(LABELSUPP_STR)-1, option, len));
2317 }
2318
2319 static inline void take_option(char **to, char *from, int *first, int len)
2320 {
2321 if (!*first) {
2322 **to = ',';
2323 *to += 1;
2324 } else
2325 *first = 0;
2326 memcpy(*to, from, len);
2327 *to += len;
2328 }
2329
2330 static inline void take_selinux_option(char **to, char *from, int *first,
2331 int len)
2332 {
2333 int current_size = 0;
2334
2335 if (!*first) {
2336 **to = '|';
2337 *to += 1;
2338 } else
2339 *first = 0;
2340
2341 while (current_size < len) {
2342 if (*from != '"') {
2343 **to = *from;
2344 *to += 1;
2345 }
2346 from += 1;
2347 current_size += 1;
2348 }
2349 }
2350
2351 static int selinux_sb_copy_data(char *orig, char *copy)
2352 {
2353 int fnosec, fsec, rc = 0;
2354 char *in_save, *in_curr, *in_end;
2355 char *sec_curr, *nosec_save, *nosec;
2356 int open_quote = 0;
2357
2358 in_curr = orig;
2359 sec_curr = copy;
2360
2361 nosec = (char *)get_zeroed_page(GFP_KERNEL);
2362 if (!nosec) {
2363 rc = -ENOMEM;
2364 goto out;
2365 }
2366
2367 nosec_save = nosec;
2368 fnosec = fsec = 1;
2369 in_save = in_end = orig;
2370
2371 do {
2372 if (*in_end == '"')
2373 open_quote = !open_quote;
2374 if ((*in_end == ',' && open_quote == 0) ||
2375 *in_end == '\0') {
2376 int len = in_end - in_curr;
2377
2378 if (selinux_option(in_curr, len))
2379 take_selinux_option(&sec_curr, in_curr, &fsec, len);
2380 else
2381 take_option(&nosec, in_curr, &fnosec, len);
2382
2383 in_curr = in_end + 1;
2384 }
2385 } while (*in_end++);
2386
2387 strcpy(in_save, nosec_save);
2388 free_page((unsigned long)nosec_save);
2389 out:
2390 return rc;
2391 }
2392
2393 static int selinux_sb_remount(struct super_block *sb, void *data)
2394 {
2395 int rc, i, *flags;
2396 struct security_mnt_opts opts;
2397 char *secdata, **mount_options;
2398 struct superblock_security_struct *sbsec = sb->s_security;
2399
2400 if (!(sbsec->flags & SE_SBINITIALIZED))
2401 return 0;
2402
2403 if (!data)
2404 return 0;
2405
2406 if (sb->s_type->fs_flags & FS_BINARY_MOUNTDATA)
2407 return 0;
2408
2409 security_init_mnt_opts(&opts);
2410 secdata = alloc_secdata();
2411 if (!secdata)
2412 return -ENOMEM;
2413 rc = selinux_sb_copy_data(data, secdata);
2414 if (rc)
2415 goto out_free_secdata;
2416
2417 rc = selinux_parse_opts_str(secdata, &opts);
2418 if (rc)
2419 goto out_free_secdata;
2420
2421 mount_options = opts.mnt_opts;
2422 flags = opts.mnt_opts_flags;
2423
2424 for (i = 0; i < opts.num_mnt_opts; i++) {
2425 u32 sid;
2426 size_t len;
2427
2428 if (flags[i] == SE_SBLABELSUPP)
2429 continue;
2430 len = strlen(mount_options[i]);
2431 rc = security_context_to_sid(mount_options[i], len, &sid);
2432 if (rc) {
2433 printk(KERN_WARNING "SELinux: security_context_to_sid"
2434 "(%s) failed for (dev %s, type %s) errno=%d\n",
2435 mount_options[i], sb->s_id, sb->s_type->name, rc);
2436 goto out_free_opts;
2437 }
2438 rc = -EINVAL;
2439 switch (flags[i]) {
2440 case FSCONTEXT_MNT:
2441 if (bad_option(sbsec, FSCONTEXT_MNT, sbsec->sid, sid))
2442 goto out_bad_option;
2443 break;
2444 case CONTEXT_MNT:
2445 if (bad_option(sbsec, CONTEXT_MNT, sbsec->mntpoint_sid, sid))
2446 goto out_bad_option;
2447 break;
2448 case ROOTCONTEXT_MNT: {
2449 struct inode_security_struct *root_isec;
2450 root_isec = sb->s_root->d_inode->i_security;
2451
2452 if (bad_option(sbsec, ROOTCONTEXT_MNT, root_isec->sid, sid))
2453 goto out_bad_option;
2454 break;
2455 }
2456 case DEFCONTEXT_MNT:
2457 if (bad_option(sbsec, DEFCONTEXT_MNT, sbsec->def_sid, sid))
2458 goto out_bad_option;
2459 break;
2460 default:
2461 goto out_free_opts;
2462 }
2463 }
2464
2465 rc = 0;
2466 out_free_opts:
2467 security_free_mnt_opts(&opts);
2468 out_free_secdata:
2469 free_secdata(secdata);
2470 return rc;
2471 out_bad_option:
2472 printk(KERN_WARNING "SELinux: unable to change security options "
2473 "during remount (dev %s, type=%s)\n", sb->s_id,
2474 sb->s_type->name);
2475 goto out_free_opts;
2476 }
2477
2478 static int selinux_sb_kern_mount(struct super_block *sb, int flags, void *data)
2479 {
2480 const struct cred *cred = current_cred();
2481 struct common_audit_data ad;
2482 int rc;
2483
2484 rc = superblock_doinit(sb, data);
2485 if (rc)
2486 return rc;
2487
2488 /* Allow all mounts performed by the kernel */
2489 if (flags & MS_KERNMOUNT)
2490 return 0;
2491
2492 COMMON_AUDIT_DATA_INIT(&ad, DENTRY);
2493 ad.u.dentry = sb->s_root;
2494 return superblock_has_perm(cred, sb, FILESYSTEM__MOUNT, &ad);
2495 }
2496
2497 static int selinux_sb_statfs(struct dentry *dentry)
2498 {
2499 const struct cred *cred = current_cred();
2500 struct common_audit_data ad;
2501
2502 COMMON_AUDIT_DATA_INIT(&ad, DENTRY);
2503 ad.u.dentry = dentry->d_sb->s_root;
2504 return superblock_has_perm(cred, dentry->d_sb, FILESYSTEM__GETATTR, &ad);
2505 }
2506
2507 static int selinux_mount(char *dev_name,
2508 struct path *path,
2509 char *type,
2510 unsigned long flags,
2511 void *data)
2512 {
2513 const struct cred *cred = current_cred();
2514
2515 if (flags & MS_REMOUNT)
2516 return superblock_has_perm(cred, path->mnt->mnt_sb,
2517 FILESYSTEM__REMOUNT, NULL);
2518 else
2519 return path_has_perm(cred, path, FILE__MOUNTON);
2520 }
2521
2522 static int selinux_umount(struct vfsmount *mnt, int flags)
2523 {
2524 const struct cred *cred = current_cred();
2525
2526 return superblock_has_perm(cred, mnt->mnt_sb,
2527 FILESYSTEM__UNMOUNT, NULL);
2528 }
2529
2530 /* inode security operations */
2531
2532 static int selinux_inode_alloc_security(struct inode *inode)
2533 {
2534 return inode_alloc_security(inode);
2535 }
2536
2537 static void selinux_inode_free_security(struct inode *inode)
2538 {
2539 inode_free_security(inode);
2540 }
2541
2542 static int selinux_inode_init_security(struct inode *inode, struct inode *dir,
2543 const struct qstr *qstr, char **name,
2544 void **value, size_t *len)
2545 {
2546 const struct task_security_struct *tsec = current_security();
2547 struct inode_security_struct *dsec;
2548 struct superblock_security_struct *sbsec;
2549 u32 sid, newsid, clen;
2550 int rc;
2551 char *namep = NULL, *context;
2552
2553 dsec = dir->i_security;
2554 sbsec = dir->i_sb->s_security;
2555
2556 sid = tsec->sid;
2557 newsid = tsec->create_sid;
2558
2559 if ((sbsec->flags & SE_SBINITIALIZED) &&
2560 (sbsec->behavior == SECURITY_FS_USE_MNTPOINT))
2561 newsid = sbsec->mntpoint_sid;
2562 else if (!newsid || !(sbsec->flags & SE_SBLABELSUPP)) {
2563 rc = security_transition_sid(sid, dsec->sid,
2564 inode_mode_to_security_class(inode->i_mode),
2565 qstr, &newsid);
2566 if (rc) {
2567 printk(KERN_WARNING "%s: "
2568 "security_transition_sid failed, rc=%d (dev=%s "
2569 "ino=%ld)\n",
2570 __func__,
2571 -rc, inode->i_sb->s_id, inode->i_ino);
2572 return rc;
2573 }
2574 }
2575
2576 /* Possibly defer initialization to selinux_complete_init. */
2577 if (sbsec->flags & SE_SBINITIALIZED) {
2578 struct inode_security_struct *isec = inode->i_security;
2579 isec->sclass = inode_mode_to_security_class(inode->i_mode);
2580 isec->sid = newsid;
2581 isec->initialized = 1;
2582 }
2583
2584 if (!ss_initialized || !(sbsec->flags & SE_SBLABELSUPP))
2585 return -EOPNOTSUPP;
2586
2587 if (name) {
2588 namep = kstrdup(XATTR_SELINUX_SUFFIX, GFP_NOFS);
2589 if (!namep)
2590 return -ENOMEM;
2591 *name = namep;
2592 }
2593
2594 if (value && len) {
2595 rc = security_sid_to_context_force(newsid, &context, &clen);
2596 if (rc) {
2597 kfree(namep);
2598 return rc;
2599 }
2600 *value = context;
2601 *len = clen;
2602 }
2603
2604 return 0;
2605 }
2606
2607 static int selinux_inode_create(struct inode *dir, struct dentry *dentry, int mask)
2608 {
2609 return may_create(dir, dentry, SECCLASS_FILE);
2610 }
2611
2612 static int selinux_inode_link(struct dentry *old_dentry, struct inode *dir, struct dentry *new_dentry)
2613 {
2614 return may_link(dir, old_dentry, MAY_LINK);
2615 }
2616
2617 static int selinux_inode_unlink(struct inode *dir, struct dentry *dentry)
2618 {
2619 return may_link(dir, dentry, MAY_UNLINK);
2620 }
2621
2622 static int selinux_inode_symlink(struct inode *dir, struct dentry *dentry, const char *name)
2623 {
2624 return may_create(dir, dentry, SECCLASS_LNK_FILE);
2625 }
2626
2627 static int selinux_inode_mkdir(struct inode *dir, struct dentry *dentry, int mask)
2628 {
2629 return may_create(dir, dentry, SECCLASS_DIR);
2630 }
2631
2632 static int selinux_inode_rmdir(struct inode *dir, struct dentry *dentry)
2633 {
2634 return may_link(dir, dentry, MAY_RMDIR);
2635 }
2636
2637 static int selinux_inode_mknod(struct inode *dir, struct dentry *dentry, int mode, dev_t dev)
2638 {
2639 return may_create(dir, dentry, inode_mode_to_security_class(mode));
2640 }
2641
2642 static int selinux_inode_rename(struct inode *old_inode, struct dentry *old_dentry,
2643 struct inode *new_inode, struct dentry *new_dentry)
2644 {
2645 return may_rename(old_inode, old_dentry, new_inode, new_dentry);
2646 }
2647
2648 static int selinux_inode_readlink(struct dentry *dentry)
2649 {
2650 const struct cred *cred = current_cred();
2651
2652 return dentry_has_perm(cred, dentry, FILE__READ);
2653 }
2654
2655 static int selinux_inode_follow_link(struct dentry *dentry, struct nameidata *nameidata)
2656 {
2657 const struct cred *cred = current_cred();
2658
2659 return dentry_has_perm(cred, dentry, FILE__READ);
2660 }
2661
2662 static int selinux_inode_permission(struct inode *inode, int mask, unsigned flags)
2663 {
2664 const struct cred *cred = current_cred();
2665 struct common_audit_data ad;
2666 u32 perms;
2667 bool from_access;
2668
2669 from_access = mask & MAY_ACCESS;
2670 mask &= (MAY_READ|MAY_WRITE|MAY_EXEC|MAY_APPEND);
2671
2672 /* No permission to check. Existence test. */
2673 if (!mask)
2674 return 0;
2675
2676 COMMON_AUDIT_DATA_INIT(&ad, INODE);
2677 ad.u.inode = inode;
2678
2679 if (from_access)
2680 ad.selinux_audit_data.auditdeny |= FILE__AUDIT_ACCESS;
2681
2682 perms = file_mask_to_av(inode->i_mode, mask);
2683
2684 return inode_has_perm(cred, inode, perms, &ad, flags);
2685 }
2686
2687 static int selinux_inode_setattr(struct dentry *dentry, struct iattr *iattr)
2688 {
2689 const struct cred *cred = current_cred();
2690 unsigned int ia_valid = iattr->ia_valid;
2691
2692 /* ATTR_FORCE is just used for ATTR_KILL_S[UG]ID. */
2693 if (ia_valid & ATTR_FORCE) {
2694 ia_valid &= ~(ATTR_KILL_SUID | ATTR_KILL_SGID | ATTR_MODE |
2695 ATTR_FORCE);
2696 if (!ia_valid)
2697 return 0;
2698 }
2699
2700 if (ia_valid & (ATTR_MODE | ATTR_UID | ATTR_GID |
2701 ATTR_ATIME_SET | ATTR_MTIME_SET | ATTR_TIMES_SET))
2702 return dentry_has_perm(cred, dentry, FILE__SETATTR);
2703
2704 return dentry_has_perm(cred, dentry, FILE__WRITE);
2705 }
2706
2707 static int selinux_inode_getattr(struct vfsmount *mnt, struct dentry *dentry)
2708 {
2709 const struct cred *cred = current_cred();
2710 struct path path;
2711
2712 path.dentry = dentry;
2713 path.mnt = mnt;
2714
2715 return path_has_perm(cred, &path, FILE__GETATTR);
2716 }
2717
2718 static int selinux_inode_setotherxattr(struct dentry *dentry, const char *name)
2719 {
2720 const struct cred *cred = current_cred();
2721
2722 if (!strncmp(name, XATTR_SECURITY_PREFIX,
2723 sizeof XATTR_SECURITY_PREFIX - 1)) {
2724 if (!strcmp(name, XATTR_NAME_CAPS)) {
2725 if (!capable(CAP_SETFCAP))
2726 return -EPERM;
2727 } else if (!capable(CAP_SYS_ADMIN)) {
2728 /* A different attribute in the security namespace.
2729 Restrict to administrator. */
2730 return -EPERM;
2731 }
2732 }
2733
2734 /* Not an attribute we recognize, so just check the
2735 ordinary setattr permission. */
2736 return dentry_has_perm(cred, dentry, FILE__SETATTR);
2737 }
2738
2739 static int selinux_inode_setxattr(struct dentry *dentry, const char *name,
2740 const void *value, size_t size, int flags)
2741 {
2742 struct inode *inode = dentry->d_inode;
2743 struct inode_security_struct *isec = inode->i_security;
2744 struct superblock_security_struct *sbsec;
2745 struct common_audit_data ad;
2746 u32 newsid, sid = current_sid();
2747 int rc = 0;
2748
2749 if (strcmp(name, XATTR_NAME_SELINUX))
2750 return selinux_inode_setotherxattr(dentry, name);
2751
2752 sbsec = inode->i_sb->s_security;
2753 if (!(sbsec->flags & SE_SBLABELSUPP))
2754 return -EOPNOTSUPP;
2755
2756 if (!inode_owner_or_capable(inode))
2757 return -EPERM;
2758
2759 COMMON_AUDIT_DATA_INIT(&ad, DENTRY);
2760 ad.u.dentry = dentry;
2761
2762 rc = avc_has_perm(sid, isec->sid, isec->sclass,
2763 FILE__RELABELFROM, &ad);
2764 if (rc)
2765 return rc;
2766
2767 rc = security_context_to_sid(value, size, &newsid);
2768 if (rc == -EINVAL) {
2769 if (!capable(CAP_MAC_ADMIN))
2770 return rc;
2771 rc = security_context_to_sid_force(value, size, &newsid);
2772 }
2773 if (rc)
2774 return rc;
2775
2776 rc = avc_has_perm(sid, newsid, isec->sclass,
2777 FILE__RELABELTO, &ad);
2778 if (rc)
2779 return rc;
2780
2781 rc = security_validate_transition(isec->sid, newsid, sid,
2782 isec->sclass);
2783 if (rc)
2784 return rc;
2785
2786 return avc_has_perm(newsid,
2787 sbsec->sid,
2788 SECCLASS_FILESYSTEM,
2789 FILESYSTEM__ASSOCIATE,
2790 &ad);
2791 }
2792
2793 static void selinux_inode_post_setxattr(struct dentry *dentry, const char *name,
2794 const void *value, size_t size,
2795 int flags)
2796 {
2797 struct inode *inode = dentry->d_inode;
2798 struct inode_security_struct *isec = inode->i_security;
2799 u32 newsid;
2800 int rc;
2801
2802 if (strcmp(name, XATTR_NAME_SELINUX)) {
2803 /* Not an attribute we recognize, so nothing to do. */
2804 return;
2805 }
2806
2807 rc = security_context_to_sid_force(value, size, &newsid);
2808 if (rc) {
2809 printk(KERN_ERR "SELinux: unable to map context to SID"
2810 "for (%s, %lu), rc=%d\n",
2811 inode->i_sb->s_id, inode->i_ino, -rc);
2812 return;
2813 }
2814
2815 isec->sid = newsid;
2816 return;
2817 }
2818
2819 static int selinux_inode_getxattr(struct dentry *dentry, const char *name)
2820 {
2821 const struct cred *cred = current_cred();
2822
2823 return dentry_has_perm(cred, dentry, FILE__GETATTR);
2824 }
2825
2826 static int selinux_inode_listxattr(struct dentry *dentry)
2827 {
2828 const struct cred *cred = current_cred();
2829
2830 return dentry_has_perm(cred, dentry, FILE__GETATTR);
2831 }
2832
2833 static int selinux_inode_removexattr(struct dentry *dentry, const char *name)
2834 {
2835 if (strcmp(name, XATTR_NAME_SELINUX))
2836 return selinux_inode_setotherxattr(dentry, name);
2837
2838 /* No one is allowed to remove a SELinux security label.
2839 You can change the label, but all data must be labeled. */
2840 return -EACCES;
2841 }
2842
2843 /*
2844 * Copy the inode security context value to the user.
2845 *
2846 * Permission check is handled by selinux_inode_getxattr hook.
2847 */
2848 static int selinux_inode_getsecurity(const struct inode *inode, const char *name, void **buffer, bool alloc)
2849 {
2850 u32 size;
2851 int error;
2852 char *context = NULL;
2853 struct inode_security_struct *isec = inode->i_security;
2854
2855 if (strcmp(name, XATTR_SELINUX_SUFFIX))
2856 return -EOPNOTSUPP;
2857
2858 /*
2859 * If the caller has CAP_MAC_ADMIN, then get the raw context
2860 * value even if it is not defined by current policy; otherwise,
2861 * use the in-core value under current policy.
2862 * Use the non-auditing forms of the permission checks since
2863 * getxattr may be called by unprivileged processes commonly
2864 * and lack of permission just means that we fall back to the
2865 * in-core context value, not a denial.
2866 */
2867 error = selinux_capable(current, current_cred(),
2868 &init_user_ns, CAP_MAC_ADMIN,
2869 SECURITY_CAP_NOAUDIT);
2870 if (!error)
2871 error = security_sid_to_context_force(isec->sid, &context,
2872 &size);
2873 else
2874 error = security_sid_to_context(isec->sid, &context, &size);
2875 if (error)
2876 return error;
2877 error = size;
2878 if (alloc) {
2879 *buffer = context;
2880 goto out_nofree;
2881 }
2882 kfree(context);
2883 out_nofree:
2884 return error;
2885 }
2886
2887 static int selinux_inode_setsecurity(struct inode *inode, const char *name,
2888 const void *value, size_t size, int flags)
2889 {
2890 struct inode_security_struct *isec = inode->i_security;
2891 u32 newsid;
2892 int rc;
2893
2894 if (strcmp(name, XATTR_SELINUX_SUFFIX))
2895 return -EOPNOTSUPP;
2896
2897 if (!value || !size)
2898 return -EACCES;
2899
2900 rc = security_context_to_sid((void *)value, size, &newsid);
2901 if (rc)
2902 return rc;
2903
2904 isec->sid = newsid;
2905 isec->initialized = 1;
2906 return 0;
2907 }
2908
2909 static int selinux_inode_listsecurity(struct inode *inode, char *buffer, size_t buffer_size)
2910 {
2911 const int len = sizeof(XATTR_NAME_SELINUX);
2912 if (buffer && len <= buffer_size)
2913 memcpy(buffer, XATTR_NAME_SELINUX, len);
2914 return len;
2915 }
2916
2917 static void selinux_inode_getsecid(const struct inode *inode, u32 *secid)
2918 {
2919 struct inode_security_struct *isec = inode->i_security;
2920 *secid = isec->sid;
2921 }
2922
2923 /* file security operations */
2924
2925 static int selinux_revalidate_file_permission(struct file *file, int mask)
2926 {
2927 const struct cred *cred = current_cred();
2928 struct inode *inode = file->f_path.dentry->d_inode;
2929
2930 /* file_mask_to_av won't add FILE__WRITE if MAY_APPEND is set */
2931 if ((file->f_flags & O_APPEND) && (mask & MAY_WRITE))
2932 mask |= MAY_APPEND;
2933
2934 return file_has_perm(cred, file,
2935 file_mask_to_av(inode->i_mode, mask));
2936 }
2937
2938 static int selinux_file_permission(struct file *file, int mask)
2939 {
2940 struct inode *inode = file->f_path.dentry->d_inode;
2941 struct file_security_struct *fsec = file->f_security;
2942 struct inode_security_struct *isec = inode->i_security;
2943 u32 sid = current_sid();
2944
2945 if (!mask)
2946 /* No permission to check. Existence test. */
2947 return 0;
2948
2949 if (sid == fsec->sid && fsec->isid == isec->sid &&
2950 fsec->pseqno == avc_policy_seqno())
2951 /* No change since dentry_open check. */
2952 return 0;
2953
2954 return selinux_revalidate_file_permission(file, mask);
2955 }
2956
2957 static int selinux_file_alloc_security(struct file *file)
2958 {
2959 return file_alloc_security(file);
2960 }
2961
2962 static void selinux_file_free_security(struct file *file)
2963 {
2964 file_free_security(file);
2965 }
2966
2967 static int selinux_file_ioctl(struct file *file, unsigned int cmd,
2968 unsigned long arg)
2969 {
2970 const struct cred *cred = current_cred();
2971 int error = 0;
2972
2973 switch (cmd) {
2974 case FIONREAD:
2975 /* fall through */
2976 case FIBMAP:
2977 /* fall through */
2978 case FIGETBSZ:
2979 /* fall through */
2980 case EXT2_IOC_GETFLAGS:
2981 /* fall through */
2982 case EXT2_IOC_GETVERSION:
2983 error = file_has_perm(cred, file, FILE__GETATTR);
2984 break;
2985
2986 case EXT2_IOC_SETFLAGS:
2987 /* fall through */
2988 case EXT2_IOC_SETVERSION:
2989 error = file_has_perm(cred, file, FILE__SETATTR);
2990 break;
2991
2992 /* sys_ioctl() checks */
2993 case FIONBIO:
2994 /* fall through */
2995 case FIOASYNC:
2996 error = file_has_perm(cred, file, 0);
2997 break;
2998
2999 case KDSKBENT:
3000 case KDSKBSENT:
3001 error = task_has_capability(current, cred, CAP_SYS_TTY_CONFIG,
3002 SECURITY_CAP_AUDIT);
3003 break;
3004
3005 /* default case assumes that the command will go
3006 * to the file's ioctl() function.
3007 */
3008 default:
3009 error = file_has_perm(cred, file, FILE__IOCTL);
3010 }
3011 return error;
3012 }
3013
3014 static int default_noexec;
3015
3016 static int file_map_prot_check(struct file *file, unsigned long prot, int shared)
3017 {
3018 const struct cred *cred = current_cred();
3019 int rc = 0;
3020
3021 if (default_noexec &&
3022 (prot & PROT_EXEC) && (!file || (!shared && (prot & PROT_WRITE)))) {
3023 /*
3024 * We are making executable an anonymous mapping or a
3025 * private file mapping that will also be writable.
3026 * This has an additional check.
3027 */
3028 rc = cred_has_perm(cred, cred, PROCESS__EXECMEM);
3029 if (rc)
3030 goto error;
3031 }
3032
3033 if (file) {
3034 /* read access is always possible with a mapping */
3035 u32 av = FILE__READ;
3036
3037 /* write access only matters if the mapping is shared */
3038 if (shared && (prot & PROT_WRITE))
3039 av |= FILE__WRITE;
3040
3041 if (prot & PROT_EXEC)
3042 av |= FILE__EXECUTE;
3043
3044 return file_has_perm(cred, file, av);
3045 }
3046
3047 error:
3048 return rc;
3049 }
3050
3051 static int selinux_file_mmap(struct file *file, unsigned long reqprot,
3052 unsigned long prot, unsigned long flags,
3053 unsigned long addr, unsigned long addr_only)
3054 {
3055 int rc = 0;
3056 u32 sid = current_sid();
3057
3058 /*
3059 * notice that we are intentionally putting the SELinux check before
3060 * the secondary cap_file_mmap check. This is such a likely attempt
3061 * at bad behaviour/exploit that we always want to get the AVC, even
3062 * if DAC would have also denied the operation.
3063 */
3064 if (addr < CONFIG_LSM_MMAP_MIN_ADDR) {
3065 rc = avc_has_perm(sid, sid, SECCLASS_MEMPROTECT,
3066 MEMPROTECT__MMAP_ZERO, NULL);
3067 if (rc)
3068 return rc;
3069 }
3070
3071 /* do DAC check on address space usage */
3072 rc = cap_file_mmap(file, reqprot, prot, flags, addr, addr_only);
3073 if (rc || addr_only)
3074 return rc;
3075
3076 if (selinux_checkreqprot)
3077 prot = reqprot;
3078
3079 return file_map_prot_check(file, prot,
3080 (flags & MAP_TYPE) == MAP_SHARED);
3081 }
3082
3083 static int selinux_file_mprotect(struct vm_area_struct *vma,
3084 unsigned long reqprot,
3085 unsigned long prot)
3086 {
3087 const struct cred *cred = current_cred();
3088
3089 if (selinux_checkreqprot)
3090 prot = reqprot;
3091
3092 if (default_noexec &&
3093 (prot & PROT_EXEC) && !(vma->vm_flags & VM_EXEC)) {
3094 int rc = 0;
3095 if (vma->vm_start >= vma->vm_mm->start_brk &&
3096 vma->vm_end <= vma->vm_mm->brk) {
3097 rc = cred_has_perm(cred, cred, PROCESS__EXECHEAP);
3098 } else if (!vma->vm_file &&
3099 vma->vm_start <= vma->vm_mm->start_stack &&
3100 vma->vm_end >= vma->vm_mm->start_stack) {
3101 rc = current_has_perm(current, PROCESS__EXECSTACK);
3102 } else if (vma->vm_file && vma->anon_vma) {
3103 /*
3104 * We are making executable a file mapping that has
3105 * had some COW done. Since pages might have been
3106 * written, check ability to execute the possibly
3107 * modified content. This typically should only
3108 * occur for text relocations.
3109 */
3110 rc = file_has_perm(cred, vma->vm_file, FILE__EXECMOD);
3111 }
3112 if (rc)
3113 return rc;
3114 }
3115
3116 return file_map_prot_check(vma->vm_file, prot, vma->vm_flags&VM_SHARED);
3117 }
3118
3119 static int selinux_file_lock(struct file *file, unsigned int cmd)
3120 {
3121 const struct cred *cred = current_cred();
3122
3123 return file_has_perm(cred, file, FILE__LOCK);
3124 }
3125
3126 static int selinux_file_fcntl(struct file *file, unsigned int cmd,
3127 unsigned long arg)
3128 {
3129 const struct cred *cred = current_cred();
3130 int err = 0;
3131
3132 switch (cmd) {
3133 case F_SETFL:
3134 if (!file->f_path.dentry || !file->f_path.dentry->d_inode) {
3135 err = -EINVAL;
3136 break;
3137 }
3138
3139 if ((file->f_flags & O_APPEND) && !(arg & O_APPEND)) {
3140 err = file_has_perm(cred, file, FILE__WRITE);
3141 break;
3142 }
3143 /* fall through */
3144 case F_SETOWN:
3145 case F_SETSIG:
3146 case F_GETFL:
3147 case F_GETOWN:
3148 case F_GETSIG:
3149 /* Just check FD__USE permission */
3150 err = file_has_perm(cred, file, 0);
3151 break;
3152 case F_GETLK:
3153 case F_SETLK:
3154 case F_SETLKW:
3155 #if BITS_PER_LONG == 32
3156 case F_GETLK64:
3157 case F_SETLK64:
3158 case F_SETLKW64:
3159 #endif
3160 if (!file->f_path.dentry || !file->f_path.dentry->d_inode) {
3161 err = -EINVAL;
3162 break;
3163 }
3164 err = file_has_perm(cred, file, FILE__LOCK);
3165 break;
3166 }
3167
3168 return err;
3169 }
3170
3171 static int selinux_file_set_fowner(struct file *file)
3172 {
3173 struct file_security_struct *fsec;
3174
3175 fsec = file->f_security;
3176 fsec->fown_sid = current_sid();
3177
3178 return 0;
3179 }
3180
3181 static int selinux_file_send_sigiotask(struct task_struct *tsk,
3182 struct fown_struct *fown, int signum)
3183 {
3184 struct file *file;
3185 u32 sid = task_sid(tsk);
3186 u32 perm;
3187 struct file_security_struct *fsec;
3188
3189 /* struct fown_struct is never outside the context of a struct file */
3190 file = container_of(fown, struct file, f_owner);
3191
3192 fsec = file->f_security;
3193
3194 if (!signum)
3195 perm = signal_to_av(SIGIO); /* as per send_sigio_to_task */
3196 else
3197 perm = signal_to_av(signum);
3198
3199 return avc_has_perm(fsec->fown_sid, sid,
3200 SECCLASS_PROCESS, perm, NULL);
3201 }
3202
3203 static int selinux_file_receive(struct file *file)
3204 {
3205 const struct cred *cred = current_cred();
3206
3207 return file_has_perm(cred, file, file_to_av(file));
3208 }
3209
3210 static int selinux_dentry_open(struct file *file, const struct cred *cred)
3211 {
3212 struct file_security_struct *fsec;
3213 struct inode *inode;
3214 struct inode_security_struct *isec;
3215
3216 inode = file->f_path.dentry->d_inode;
3217 fsec = file->f_security;
3218 isec = inode->i_security;
3219 /*
3220 * Save inode label and policy sequence number
3221 * at open-time so that selinux_file_permission
3222 * can determine whether revalidation is necessary.
3223 * Task label is already saved in the file security
3224 * struct as its SID.
3225 */
3226 fsec->isid = isec->sid;
3227 fsec->pseqno = avc_policy_seqno();
3228 /*
3229 * Since the inode label or policy seqno may have changed
3230 * between the selinux_inode_permission check and the saving
3231 * of state above, recheck that access is still permitted.
3232 * Otherwise, access might never be revalidated against the
3233 * new inode label or new policy.
3234 * This check is not redundant - do not remove.
3235 */
3236 return inode_has_perm_noadp(cred, inode, open_file_to_av(file), 0);
3237 }
3238
3239 /* task security operations */
3240
3241 static int selinux_task_create(unsigned long clone_flags)
3242 {
3243 return current_has_perm(current, PROCESS__FORK);
3244 }
3245
3246 /*
3247 * allocate the SELinux part of blank credentials
3248 */
3249 static int selinux_cred_alloc_blank(struct cred *cred, gfp_t gfp)
3250 {
3251 struct task_security_struct *tsec;
3252
3253 tsec = kzalloc(sizeof(struct task_security_struct), gfp);
3254 if (!tsec)
3255 return -ENOMEM;
3256
3257 cred->security = tsec;
3258 return 0;
3259 }
3260
3261 /*
3262 * detach and free the LSM part of a set of credentials
3263 */
3264 static void selinux_cred_free(struct cred *cred)
3265 {
3266 struct task_security_struct *tsec = cred->security;
3267
3268 /*
3269 * cred->security == NULL if security_cred_alloc_blank() or
3270 * security_prepare_creds() returned an error.
3271 */
3272 BUG_ON(cred->security && (unsigned long) cred->security < PAGE_SIZE);
3273 cred->security = (void *) 0x7UL;
3274 kfree(tsec);
3275 }
3276
3277 /*
3278 * prepare a new set of credentials for modification
3279 */
3280 static int selinux_cred_prepare(struct cred *new, const struct cred *old,
3281 gfp_t gfp)
3282 {
3283 const struct task_security_struct *old_tsec;
3284 struct task_security_struct *tsec;
3285
3286 old_tsec = old->security;
3287
3288 tsec = kmemdup(old_tsec, sizeof(struct task_security_struct), gfp);
3289 if (!tsec)
3290 return -ENOMEM;
3291
3292 new->security = tsec;
3293 return 0;
3294 }
3295
3296 /*
3297 * transfer the SELinux data to a blank set of creds
3298 */
3299 static void selinux_cred_transfer(struct cred *new, const struct cred *old)
3300 {
3301 const struct task_security_struct *old_tsec = old->security;
3302 struct task_security_struct *tsec = new->security;
3303
3304 *tsec = *old_tsec;
3305 }
3306
3307 /*
3308 * set the security data for a kernel service
3309 * - all the creation contexts are set to unlabelled
3310 */
3311 static int selinux_kernel_act_as(struct cred *new, u32 secid)
3312 {
3313 struct task_security_struct *tsec = new->security;
3314 u32 sid = current_sid();
3315 int ret;
3316
3317 ret = avc_has_perm(sid, secid,
3318 SECCLASS_KERNEL_SERVICE,
3319 KERNEL_SERVICE__USE_AS_OVERRIDE,
3320 NULL);
3321 if (ret == 0) {
3322 tsec->sid = secid;
3323 tsec->create_sid = 0;
3324 tsec->keycreate_sid = 0;
3325 tsec->sockcreate_sid = 0;
3326 }
3327 return ret;
3328 }
3329
3330 /*
3331 * set the file creation context in a security record to the same as the
3332 * objective context of the specified inode
3333 */
3334 static int selinux_kernel_create_files_as(struct cred *new, struct inode *inode)
3335 {
3336 struct inode_security_struct *isec = inode->i_security;
3337 struct task_security_struct *tsec = new->security;
3338 u32 sid = current_sid();
3339 int ret;
3340
3341 ret = avc_has_perm(sid, isec->sid,
3342 SECCLASS_KERNEL_SERVICE,
3343 KERNEL_SERVICE__CREATE_FILES_AS,
3344 NULL);
3345
3346 if (ret == 0)
3347 tsec->create_sid = isec->sid;
3348 return ret;
3349 }
3350
3351 static int selinux_kernel_module_request(char *kmod_name)
3352 {
3353 u32 sid;
3354 struct common_audit_data ad;
3355
3356 sid = task_sid(current);
3357
3358 COMMON_AUDIT_DATA_INIT(&ad, KMOD);
3359 ad.u.kmod_name = kmod_name;
3360
3361 return avc_has_perm(sid, SECINITSID_KERNEL, SECCLASS_SYSTEM,
3362 SYSTEM__MODULE_REQUEST, &ad);
3363 }
3364
3365 static int selinux_task_setpgid(struct task_struct *p, pid_t pgid)
3366 {
3367 return current_has_perm(p, PROCESS__SETPGID);
3368 }
3369
3370 static int selinux_task_getpgid(struct task_struct *p)
3371 {
3372 return current_has_perm(p, PROCESS__GETPGID);
3373 }
3374
3375 static int selinux_task_getsid(struct task_struct *p)
3376 {
3377 return current_has_perm(p, PROCESS__GETSESSION);
3378 }
3379
3380 static void selinux_task_getsecid(struct task_struct *p, u32 *secid)
3381 {
3382 *secid = task_sid(p);
3383 }
3384
3385 static int selinux_task_setnice(struct task_struct *p, int nice)
3386 {
3387 int rc;
3388
3389 rc = cap_task_setnice(p, nice);
3390 if (rc)
3391 return rc;
3392
3393 return current_has_perm(p, PROCESS__SETSCHED);
3394 }
3395
3396 static int selinux_task_setioprio(struct task_struct *p, int ioprio)
3397 {
3398 int rc;
3399
3400 rc = cap_task_setioprio(p, ioprio);
3401 if (rc)
3402 return rc;
3403
3404 return current_has_perm(p, PROCESS__SETSCHED);
3405 }
3406
3407 static int selinux_task_getioprio(struct task_struct *p)
3408 {
3409 return current_has_perm(p, PROCESS__GETSCHED);
3410 }
3411
3412 static int selinux_task_setrlimit(struct task_struct *p, unsigned int resource,
3413 struct rlimit *new_rlim)
3414 {
3415 struct rlimit *old_rlim = p->signal->rlim + resource;
3416
3417 /* Control the ability to change the hard limit (whether
3418 lowering or raising it), so that the hard limit can
3419 later be used as a safe reset point for the soft limit
3420 upon context transitions. See selinux_bprm_committing_creds. */
3421 if (old_rlim->rlim_max != new_rlim->rlim_max)
3422 return current_has_perm(p, PROCESS__SETRLIMIT);
3423
3424 return 0;
3425 }
3426
3427 static int selinux_task_setscheduler(struct task_struct *p)
3428 {
3429 int rc;
3430
3431 rc = cap_task_setscheduler(p);
3432 if (rc)
3433 return rc;
3434
3435 return current_has_perm(p, PROCESS__SETSCHED);
3436 }
3437
3438 static int selinux_task_getscheduler(struct task_struct *p)
3439 {
3440 return current_has_perm(p, PROCESS__GETSCHED);
3441 }
3442
3443 static int selinux_task_movememory(struct task_struct *p)
3444 {
3445 return current_has_perm(p, PROCESS__SETSCHED);
3446 }
3447
3448 static int selinux_task_kill(struct task_struct *p, struct siginfo *info,
3449 int sig, u32 secid)
3450 {
3451 u32 perm;
3452 int rc;
3453
3454 if (!sig)
3455 perm = PROCESS__SIGNULL; /* null signal; existence test */
3456 else
3457 perm = signal_to_av(sig);
3458 if (secid)
3459 rc = avc_has_perm(secid, task_sid(p),
3460 SECCLASS_PROCESS, perm, NULL);
3461 else
3462 rc = current_has_perm(p, perm);
3463 return rc;
3464 }
3465
3466 static int selinux_task_wait(struct task_struct *p)
3467 {
3468 return task_has_perm(p, current, PROCESS__SIGCHLD);
3469 }
3470
3471 static void selinux_task_to_inode(struct task_struct *p,
3472 struct inode *inode)
3473 {
3474 struct inode_security_struct *isec = inode->i_security;
3475 u32 sid = task_sid(p);
3476
3477 isec->sid = sid;
3478 isec->initialized = 1;
3479 }
3480
3481 /* Returns error only if unable to parse addresses */
3482 static int selinux_parse_skb_ipv4(struct sk_buff *skb,
3483 struct common_audit_data *ad, u8 *proto)
3484 {
3485 int offset, ihlen, ret = -EINVAL;
3486 struct iphdr _iph, *ih;
3487
3488 offset = skb_network_offset(skb);
3489 ih = skb_header_pointer(skb, offset, sizeof(_iph), &_iph);
3490 if (ih == NULL)
3491 goto out;
3492
3493 ihlen = ih->ihl * 4;
3494 if (ihlen < sizeof(_iph))
3495 goto out;
3496
3497 ad->u.net.v4info.saddr = ih->saddr;
3498 ad->u.net.v4info.daddr = ih->daddr;
3499 ret = 0;
3500
3501 if (proto)
3502 *proto = ih->protocol;
3503
3504 switch (ih->protocol) {
3505 case IPPROTO_TCP: {
3506 struct tcphdr _tcph, *th;
3507
3508 if (ntohs(ih->frag_off) & IP_OFFSET)
3509 break;
3510
3511 offset += ihlen;
3512 th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph);
3513 if (th == NULL)
3514 break;
3515
3516 ad->u.net.sport = th->source;
3517 ad->u.net.dport = th->dest;
3518 break;
3519 }
3520
3521 case IPPROTO_UDP: {
3522 struct udphdr _udph, *uh;
3523
3524 if (ntohs(ih->frag_off) & IP_OFFSET)
3525 break;
3526
3527 offset += ihlen;
3528 uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph);
3529 if (uh == NULL)
3530 break;
3531
3532 ad->u.net.sport = uh->source;
3533 ad->u.net.dport = uh->dest;
3534 break;
3535 }
3536
3537 case IPPROTO_DCCP: {
3538 struct dccp_hdr _dccph, *dh;
3539
3540 if (ntohs(ih->frag_off) & IP_OFFSET)
3541 break;
3542
3543 offset += ihlen;
3544 dh = skb_header_pointer(skb, offset, sizeof(_dccph), &_dccph);
3545 if (dh == NULL)
3546 break;
3547
3548 ad->u.net.sport = dh->dccph_sport;
3549 ad->u.net.dport = dh->dccph_dport;
3550 break;
3551 }
3552
3553 default:
3554 break;
3555 }
3556 out:
3557 return ret;
3558 }
3559
3560 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
3561
3562 /* Returns error only if unable to parse addresses */
3563 static int selinux_parse_skb_ipv6(struct sk_buff *skb,
3564 struct common_audit_data *ad, u8 *proto)
3565 {
3566 u8 nexthdr;
3567 int ret = -EINVAL, offset;
3568 struct ipv6hdr _ipv6h, *ip6;
3569
3570 offset = skb_network_offset(skb);
3571 ip6 = skb_header_pointer(skb, offset, sizeof(_ipv6h), &_ipv6h);
3572 if (ip6 == NULL)
3573 goto out;
3574
3575 ipv6_addr_copy(&ad->u.net.v6info.saddr, &ip6->saddr);
3576 ipv6_addr_copy(&ad->u.net.v6info.daddr, &ip6->daddr);
3577 ret = 0;
3578
3579 nexthdr = ip6->nexthdr;
3580 offset += sizeof(_ipv6h);
3581 offset = ipv6_skip_exthdr(skb, offset, &nexthdr);
3582 if (offset < 0)
3583 goto out;
3584
3585 if (proto)
3586 *proto = nexthdr;
3587
3588 switch (nexthdr) {
3589 case IPPROTO_TCP: {
3590 struct tcphdr _tcph, *th;
3591
3592 th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph);
3593 if (th == NULL)
3594 break;
3595
3596 ad->u.net.sport = th->source;
3597 ad->u.net.dport = th->dest;
3598 break;
3599 }
3600
3601 case IPPROTO_UDP: {
3602 struct udphdr _udph, *uh;
3603
3604 uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph);
3605 if (uh == NULL)
3606 break;
3607
3608 ad->u.net.sport = uh->source;
3609 ad->u.net.dport = uh->dest;
3610 break;
3611 }
3612
3613 case IPPROTO_DCCP: {
3614 struct dccp_hdr _dccph, *dh;
3615
3616 dh = skb_header_pointer(skb, offset, sizeof(_dccph), &_dccph);
3617 if (dh == NULL)
3618 break;
3619
3620 ad->u.net.sport = dh->dccph_sport;
3621 ad->u.net.dport = dh->dccph_dport;
3622 break;
3623 }
3624
3625 /* includes fragments */
3626 default:
3627 break;
3628 }
3629 out:
3630 return ret;
3631 }
3632
3633 #endif /* IPV6 */
3634
3635 static int selinux_parse_skb(struct sk_buff *skb, struct common_audit_data *ad,
3636 char **_addrp, int src, u8 *proto)
3637 {
3638 char *addrp;
3639 int ret;
3640
3641 switch (ad->u.net.family) {
3642 case PF_INET:
3643 ret = selinux_parse_skb_ipv4(skb, ad, proto);
3644 if (ret)
3645 goto parse_error;
3646 addrp = (char *)(src ? &ad->u.net.v4info.saddr :
3647 &ad->u.net.v4info.daddr);
3648 goto okay;
3649
3650 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
3651 case PF_INET6:
3652 ret = selinux_parse_skb_ipv6(skb, ad, proto);
3653 if (ret)
3654 goto parse_error;
3655 addrp = (char *)(src ? &ad->u.net.v6info.saddr :
3656 &ad->u.net.v6info.daddr);
3657 goto okay;
3658 #endif /* IPV6 */
3659 default:
3660 addrp = NULL;
3661 goto okay;
3662 }
3663
3664 parse_error:
3665 printk(KERN_WARNING
3666 "SELinux: failure in selinux_parse_skb(),"
3667 " unable to parse packet\n");
3668 return ret;
3669
3670 okay:
3671 if (_addrp)
3672 *_addrp = addrp;
3673 return 0;
3674 }
3675
3676 /**
3677 * selinux_skb_peerlbl_sid - Determine the peer label of a packet
3678 * @skb: the packet
3679 * @family: protocol family
3680 * @sid: the packet's peer label SID
3681 *
3682 * Description:
3683 * Check the various different forms of network peer labeling and determine
3684 * the peer label/SID for the packet; most of the magic actually occurs in
3685 * the security server function security_net_peersid_cmp(). The function
3686 * returns zero if the value in @sid is valid (although it may be SECSID_NULL)
3687 * or -EACCES if @sid is invalid due to inconsistencies with the different
3688 * peer labels.
3689 *
3690 */
3691 static int selinux_skb_peerlbl_sid(struct sk_buff *skb, u16 family, u32 *sid)
3692 {
3693 int err;
3694 u32 xfrm_sid;
3695 u32 nlbl_sid;
3696 u32 nlbl_type;
3697
3698 selinux_skb_xfrm_sid(skb, &xfrm_sid);
3699 selinux_netlbl_skbuff_getsid(skb, family, &nlbl_type, &nlbl_sid);
3700
3701 err = security_net_peersid_resolve(nlbl_sid, nlbl_type, xfrm_sid, sid);
3702 if (unlikely(err)) {
3703 printk(KERN_WARNING
3704 "SELinux: failure in selinux_skb_peerlbl_sid(),"
3705 " unable to determine packet's peer label\n");
3706 return -EACCES;
3707 }
3708
3709 return 0;
3710 }
3711
3712 /* socket security operations */
3713
3714 static int socket_sockcreate_sid(const struct task_security_struct *tsec,
3715 u16 secclass, u32 *socksid)
3716 {
3717 if (tsec->sockcreate_sid > SECSID_NULL) {
3718 *socksid = tsec->sockcreate_sid;
3719 return 0;
3720 }
3721
3722 return security_transition_sid(tsec->sid, tsec->sid, secclass, NULL,
3723 socksid);
3724 }
3725
3726 static int sock_has_perm(struct task_struct *task, struct sock *sk, u32 perms)
3727 {
3728 struct sk_security_struct *sksec = sk->sk_security;
3729 struct common_audit_data ad;
3730 u32 tsid = task_sid(task);
3731
3732 if (sksec->sid == SECINITSID_KERNEL)
3733 return 0;
3734
3735 COMMON_AUDIT_DATA_INIT(&ad, NET);
3736 ad.u.net.sk = sk;
3737
3738 return avc_has_perm(tsid, sksec->sid, sksec->sclass, perms, &ad);
3739 }
3740
3741 static int selinux_socket_create(int family, int type,
3742 int protocol, int kern)
3743 {
3744 const struct task_security_struct *tsec = current_security();
3745 u32 newsid;
3746 u16 secclass;
3747 int rc;
3748
3749 if (kern)
3750 return 0;
3751
3752 secclass = socket_type_to_security_class(family, type, protocol);
3753 rc = socket_sockcreate_sid(tsec, secclass, &newsid);
3754 if (rc)
3755 return rc;
3756
3757 return avc_has_perm(tsec->sid, newsid, secclass, SOCKET__CREATE, NULL);
3758 }
3759
3760 static int selinux_socket_post_create(struct socket *sock, int family,
3761 int type, int protocol, int kern)
3762 {
3763 const struct task_security_struct *tsec = current_security();
3764 struct inode_security_struct *isec = SOCK_INODE(sock)->i_security;
3765 struct sk_security_struct *sksec;
3766 int err = 0;
3767
3768 isec->sclass = socket_type_to_security_class(family, type, protocol);
3769
3770 if (kern)
3771 isec->sid = SECINITSID_KERNEL;
3772 else {
3773 err = socket_sockcreate_sid(tsec, isec->sclass, &(isec->sid));
3774 if (err)
3775 return err;
3776 }
3777
3778 isec->initialized = 1;
3779
3780 if (sock->sk) {
3781 sksec = sock->sk->sk_security;
3782 sksec->sid = isec->sid;
3783 sksec->sclass = isec->sclass;
3784 err = selinux_netlbl_socket_post_create(sock->sk, family);
3785 }
3786
3787 return err;
3788 }
3789
3790 /* Range of port numbers used to automatically bind.
3791 Need to determine whether we should perform a name_bind
3792 permission check between the socket and the port number. */
3793
3794 static int selinux_socket_bind(struct socket *sock, struct sockaddr *address, int addrlen)
3795 {
3796 struct sock *sk = sock->sk;
3797 u16 family;
3798 int err;
3799
3800 err = sock_has_perm(current, sk, SOCKET__BIND);
3801 if (err)
3802 goto out;
3803
3804 /*
3805 * If PF_INET or PF_INET6, check name_bind permission for the port.
3806 * Multiple address binding for SCTP is not supported yet: we just
3807 * check the first address now.
3808 */
3809 family = sk->sk_family;
3810 if (family == PF_INET || family == PF_INET6) {
3811 char *addrp;
3812 struct sk_security_struct *sksec = sk->sk_security;
3813 struct common_audit_data ad;
3814 struct sockaddr_in *addr4 = NULL;
3815 struct sockaddr_in6 *addr6 = NULL;
3816 unsigned short snum;
3817 u32 sid, node_perm;
3818
3819 if (family == PF_INET) {
3820 addr4 = (struct sockaddr_in *)address;
3821 snum = ntohs(addr4->sin_port);
3822 addrp = (char *)&addr4->sin_addr.s_addr;
3823 } else {
3824 addr6 = (struct sockaddr_in6 *)address;
3825 snum = ntohs(addr6->sin6_port);
3826 addrp = (char *)&addr6->sin6_addr.s6_addr;
3827 }
3828
3829 if (snum) {
3830 int low, high;
3831
3832 inet_get_local_port_range(&low, &high);
3833
3834 if (snum < max(PROT_SOCK, low) || snum > high) {
3835 err = sel_netport_sid(sk->sk_protocol,
3836 snum, &sid);
3837 if (err)
3838 goto out;
3839 COMMON_AUDIT_DATA_INIT(&ad, NET);
3840 ad.u.net.sport = htons(snum);
3841 ad.u.net.family = family;
3842 err = avc_has_perm(sksec->sid, sid,
3843 sksec->sclass,
3844 SOCKET__NAME_BIND, &ad);
3845 if (err)
3846 goto out;
3847 }
3848 }
3849
3850 switch (sksec->sclass) {
3851 case SECCLASS_TCP_SOCKET:
3852 node_perm = TCP_SOCKET__NODE_BIND;
3853 break;
3854
3855 case SECCLASS_UDP_SOCKET:
3856 node_perm = UDP_SOCKET__NODE_BIND;
3857 break;
3858
3859 case SECCLASS_DCCP_SOCKET:
3860 node_perm = DCCP_SOCKET__NODE_BIND;
3861 break;
3862
3863 default:
3864 node_perm = RAWIP_SOCKET__NODE_BIND;
3865 break;
3866 }
3867
3868 err = sel_netnode_sid(addrp, family, &sid);
3869 if (err)
3870 goto out;
3871
3872 COMMON_AUDIT_DATA_INIT(&ad, NET);
3873 ad.u.net.sport = htons(snum);
3874 ad.u.net.family = family;
3875
3876 if (family == PF_INET)
3877 ad.u.net.v4info.saddr = addr4->sin_addr.s_addr;
3878 else
3879 ipv6_addr_copy(&ad.u.net.v6info.saddr, &addr6->sin6_addr);
3880
3881 err = avc_has_perm(sksec->sid, sid,
3882 sksec->sclass, node_perm, &ad);
3883 if (err)
3884 goto out;
3885 }
3886 out:
3887 return err;
3888 }
3889
3890 static int selinux_socket_connect(struct socket *sock, struct sockaddr *address, int addrlen)
3891 {
3892 struct sock *sk = sock->sk;
3893 struct sk_security_struct *sksec = sk->sk_security;
3894 int err;
3895
3896 err = sock_has_perm(current, sk, SOCKET__CONNECT);
3897 if (err)
3898 return err;
3899
3900 /*
3901 * If a TCP or DCCP socket, check name_connect permission for the port.
3902 */
3903 if (sksec->sclass == SECCLASS_TCP_SOCKET ||
3904 sksec->sclass == SECCLASS_DCCP_SOCKET) {
3905 struct common_audit_data ad;
3906 struct sockaddr_in *addr4 = NULL;
3907 struct sockaddr_in6 *addr6 = NULL;
3908 unsigned short snum;
3909 u32 sid, perm;
3910
3911 if (sk->sk_family == PF_INET) {
3912 addr4 = (struct sockaddr_in *)address;
3913 if (addrlen < sizeof(struct sockaddr_in))
3914 return -EINVAL;
3915 snum = ntohs(addr4->sin_port);
3916 } else {
3917 addr6 = (struct sockaddr_in6 *)address;
3918 if (addrlen < SIN6_LEN_RFC2133)
3919 return -EINVAL;
3920 snum = ntohs(addr6->sin6_port);
3921 }
3922
3923 err = sel_netport_sid(sk->sk_protocol, snum, &sid);
3924 if (err)
3925 goto out;
3926
3927 perm = (sksec->sclass == SECCLASS_TCP_SOCKET) ?
3928 TCP_SOCKET__NAME_CONNECT : DCCP_SOCKET__NAME_CONNECT;
3929
3930 COMMON_AUDIT_DATA_INIT(&ad, NET);
3931 ad.u.net.dport = htons(snum);
3932 ad.u.net.family = sk->sk_family;
3933 err = avc_has_perm(sksec->sid, sid, sksec->sclass, perm, &ad);
3934 if (err)
3935 goto out;
3936 }
3937
3938 err = selinux_netlbl_socket_connect(sk, address);
3939
3940 out:
3941 return err;
3942 }
3943
3944 static int selinux_socket_listen(struct socket *sock, int backlog)
3945 {
3946 return sock_has_perm(current, sock->sk, SOCKET__LISTEN);
3947 }
3948
3949 static int selinux_socket_accept(struct socket *sock, struct socket *newsock)
3950 {
3951 int err;
3952 struct inode_security_struct *isec;
3953 struct inode_security_struct *newisec;
3954
3955 err = sock_has_perm(current, sock->sk, SOCKET__ACCEPT);
3956 if (err)
3957 return err;
3958
3959 newisec = SOCK_INODE(newsock)->i_security;
3960
3961 isec = SOCK_INODE(sock)->i_security;
3962 newisec->sclass = isec->sclass;
3963 newisec->sid = isec->sid;
3964 newisec->initialized = 1;
3965
3966 return 0;
3967 }
3968
3969 static int selinux_socket_sendmsg(struct socket *sock, struct msghdr *msg,
3970 int size)
3971 {
3972 return sock_has_perm(current, sock->sk, SOCKET__WRITE);
3973 }
3974
3975 static int selinux_socket_recvmsg(struct socket *sock, struct msghdr *msg,
3976 int size, int flags)
3977 {
3978 return sock_has_perm(current, sock->sk, SOCKET__READ);
3979 }
3980
3981 static int selinux_socket_getsockname(struct socket *sock)
3982 {
3983 return sock_has_perm(current, sock->sk, SOCKET__GETATTR);
3984 }
3985
3986 static int selinux_socket_getpeername(struct socket *sock)
3987 {
3988 return sock_has_perm(current, sock->sk, SOCKET__GETATTR);
3989 }
3990
3991 static int selinux_socket_setsockopt(struct socket *sock, int level, int optname)
3992 {
3993 int err;
3994
3995 err = sock_has_perm(current, sock->sk, SOCKET__SETOPT);
3996 if (err)
3997 return err;
3998
3999 return selinux_netlbl_socket_setsockopt(sock, level, optname);
4000 }
4001
4002 static int selinux_socket_getsockopt(struct socket *sock, int level,
4003 int optname)
4004 {
4005 return sock_has_perm(current, sock->sk, SOCKET__GETOPT);
4006 }
4007
4008 static int selinux_socket_shutdown(struct socket *sock, int how)
4009 {
4010 return sock_has_perm(current, sock->sk, SOCKET__SHUTDOWN);
4011 }
4012
4013 static int selinux_socket_unix_stream_connect(struct sock *sock,
4014 struct sock *other,
4015 struct sock *newsk)
4016 {
4017 struct sk_security_struct *sksec_sock = sock->sk_security;
4018 struct sk_security_struct *sksec_other = other->sk_security;
4019 struct sk_security_struct *sksec_new = newsk->sk_security;
4020 struct common_audit_data ad;
4021 int err;
4022
4023 COMMON_AUDIT_DATA_INIT(&ad, NET);
4024 ad.u.net.sk = other;
4025
4026 err = avc_has_perm(sksec_sock->sid, sksec_other->sid,
4027 sksec_other->sclass,
4028 UNIX_STREAM_SOCKET__CONNECTTO, &ad);
4029 if (err)
4030 return err;
4031
4032 /* server child socket */
4033 sksec_new->peer_sid = sksec_sock->sid;
4034 err = security_sid_mls_copy(sksec_other->sid, sksec_sock->sid,
4035 &sksec_new->sid);
4036 if (err)
4037 return err;
4038
4039 /* connecting socket */
4040 sksec_sock->peer_sid = sksec_new->sid;
4041
4042 return 0;
4043 }
4044
4045 static int selinux_socket_unix_may_send(struct socket *sock,
4046 struct socket *other)
4047 {
4048 struct sk_security_struct *ssec = sock->sk->sk_security;
4049 struct sk_security_struct *osec = other->sk->sk_security;
4050 struct common_audit_data ad;
4051
4052 COMMON_AUDIT_DATA_INIT(&ad, NET);
4053 ad.u.net.sk = other->sk;
4054
4055 return avc_has_perm(ssec->sid, osec->sid, osec->sclass, SOCKET__SENDTO,
4056 &ad);
4057 }
4058
4059 static int selinux_inet_sys_rcv_skb(int ifindex, char *addrp, u16 family,
4060 u32 peer_sid,
4061 struct common_audit_data *ad)
4062 {
4063 int err;
4064 u32 if_sid;
4065 u32 node_sid;
4066
4067 err = sel_netif_sid(ifindex, &if_sid);
4068 if (err)
4069 return err;
4070 err = avc_has_perm(peer_sid, if_sid,
4071 SECCLASS_NETIF, NETIF__INGRESS, ad);
4072 if (err)
4073 return err;
4074
4075 err = sel_netnode_sid(addrp, family, &node_sid);
4076 if (err)
4077 return err;
4078 return avc_has_perm(peer_sid, node_sid,
4079 SECCLASS_NODE, NODE__RECVFROM, ad);
4080 }
4081
4082 static int selinux_sock_rcv_skb_compat(struct sock *sk, struct sk_buff *skb,
4083 u16 family)
4084 {
4085 int err = 0;
4086 struct sk_security_struct *sksec = sk->sk_security;
4087 u32 sk_sid = sksec->sid;
4088 struct common_audit_data ad;
4089 char *addrp;
4090
4091 COMMON_AUDIT_DATA_INIT(&ad, NET);
4092 ad.u.net.netif = skb->skb_iif;
4093 ad.u.net.family = family;
4094 err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL);
4095 if (err)
4096 return err;
4097
4098 if (selinux_secmark_enabled()) {
4099 err = avc_has_perm(sk_sid, skb->secmark, SECCLASS_PACKET,
4100 PACKET__RECV, &ad);
4101 if (err)
4102 return err;
4103 }
4104
4105 err = selinux_netlbl_sock_rcv_skb(sksec, skb, family, &ad);
4106 if (err)
4107 return err;
4108 err = selinux_xfrm_sock_rcv_skb(sksec->sid, skb, &ad);
4109
4110 return err;
4111 }
4112
4113 static int selinux_socket_sock_rcv_skb(struct sock *sk, struct sk_buff *skb)
4114 {
4115 int err;
4116 struct sk_security_struct *sksec = sk->sk_security;
4117 u16 family = sk->sk_family;
4118 u32 sk_sid = sksec->sid;
4119 struct common_audit_data ad;
4120 char *addrp;
4121 u8 secmark_active;
4122 u8 peerlbl_active;
4123
4124 if (family != PF_INET && family != PF_INET6)
4125 return 0;
4126
4127 /* Handle mapped IPv4 packets arriving via IPv6 sockets */
4128 if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
4129 family = PF_INET;
4130
4131 /* If any sort of compatibility mode is enabled then handoff processing
4132 * to the selinux_sock_rcv_skb_compat() function to deal with the
4133 * special handling. We do this in an attempt to keep this function
4134 * as fast and as clean as possible. */
4135 if (!selinux_policycap_netpeer)
4136 return selinux_sock_rcv_skb_compat(sk, skb, family);
4137
4138 secmark_active = selinux_secmark_enabled();
4139 peerlbl_active = netlbl_enabled() || selinux_xfrm_enabled();
4140 if (!secmark_active && !peerlbl_active)
4141 return 0;
4142
4143 COMMON_AUDIT_DATA_INIT(&ad, NET);
4144 ad.u.net.netif = skb->skb_iif;
4145 ad.u.net.family = family;
4146 err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL);
4147 if (err)
4148 return err;
4149
4150 if (peerlbl_active) {
4151 u32 peer_sid;
4152
4153 err = selinux_skb_peerlbl_sid(skb, family, &peer_sid);
4154 if (err)
4155 return err;
4156 err = selinux_inet_sys_rcv_skb(skb->skb_iif, addrp, family,
4157 peer_sid, &ad);
4158 if (err) {
4159 selinux_netlbl_err(skb, err, 0);
4160 return err;
4161 }
4162 err = avc_has_perm(sk_sid, peer_sid, SECCLASS_PEER,
4163 PEER__RECV, &ad);
4164 if (err)
4165 selinux_netlbl_err(skb, err, 0);
4166 }
4167
4168 if (secmark_active) {
4169 err = avc_has_perm(sk_sid, skb->secmark, SECCLASS_PACKET,
4170 PACKET__RECV, &ad);
4171 if (err)
4172 return err;
4173 }
4174
4175 return err;
4176 }
4177
4178 static int selinux_socket_getpeersec_stream(struct socket *sock, char __user *optval,
4179 int __user *optlen, unsigned len)
4180 {
4181 int err = 0;
4182 char *scontext;
4183 u32 scontext_len;
4184 struct sk_security_struct *sksec = sock->sk->sk_security;
4185 u32 peer_sid = SECSID_NULL;
4186
4187 if (sksec->sclass == SECCLASS_UNIX_STREAM_SOCKET ||
4188 sksec->sclass == SECCLASS_TCP_SOCKET)
4189 peer_sid = sksec->peer_sid;
4190 if (peer_sid == SECSID_NULL)
4191 return -ENOPROTOOPT;
4192
4193 err = security_sid_to_context(peer_sid, &scontext, &scontext_len);
4194 if (err)
4195 return err;
4196
4197 if (scontext_len > len) {
4198 err = -ERANGE;
4199 goto out_len;
4200 }
4201
4202 if (copy_to_user(optval, scontext, scontext_len))
4203 err = -EFAULT;
4204
4205 out_len:
4206 if (put_user(scontext_len, optlen))
4207 err = -EFAULT;
4208 kfree(scontext);
4209 return err;
4210 }
4211
4212 static int selinux_socket_getpeersec_dgram(struct socket *sock, struct sk_buff *skb, u32 *secid)
4213 {
4214 u32 peer_secid = SECSID_NULL;
4215 u16 family;
4216
4217 if (skb && skb->protocol == htons(ETH_P_IP))
4218 family = PF_INET;
4219 else if (skb && skb->protocol == htons(ETH_P_IPV6))
4220 family = PF_INET6;
4221 else if (sock)
4222 family = sock->sk->sk_family;
4223 else
4224 goto out;
4225
4226 if (sock && family == PF_UNIX)
4227 selinux_inode_getsecid(SOCK_INODE(sock), &peer_secid);
4228 else if (skb)
4229 selinux_skb_peerlbl_sid(skb, family, &peer_secid);
4230
4231 out:
4232 *secid = peer_secid;
4233 if (peer_secid == SECSID_NULL)
4234 return -EINVAL;
4235 return 0;
4236 }
4237
4238 static int selinux_sk_alloc_security(struct sock *sk, int family, gfp_t priority)
4239 {
4240 struct sk_security_struct *sksec;
4241
4242 sksec = kzalloc(sizeof(*sksec), priority);
4243 if (!sksec)
4244 return -ENOMEM;
4245
4246 sksec->peer_sid = SECINITSID_UNLABELED;
4247 sksec->sid = SECINITSID_UNLABELED;
4248 selinux_netlbl_sk_security_reset(sksec);
4249 sk->sk_security = sksec;
4250
4251 return 0;
4252 }
4253
4254 static void selinux_sk_free_security(struct sock *sk)
4255 {
4256 struct sk_security_struct *sksec = sk->sk_security;
4257
4258 sk->sk_security = NULL;
4259 selinux_netlbl_sk_security_free(sksec);
4260 kfree(sksec);
4261 }
4262
4263 static void selinux_sk_clone_security(const struct sock *sk, struct sock *newsk)
4264 {
4265 struct sk_security_struct *sksec = sk->sk_security;
4266 struct sk_security_struct *newsksec = newsk->sk_security;
4267
4268 newsksec->sid = sksec->sid;
4269 newsksec->peer_sid = sksec->peer_sid;
4270 newsksec->sclass = sksec->sclass;
4271
4272 selinux_netlbl_sk_security_reset(newsksec);
4273 }
4274
4275 static void selinux_sk_getsecid(struct sock *sk, u32 *secid)
4276 {
4277 if (!sk)
4278 *secid = SECINITSID_ANY_SOCKET;
4279 else {
4280 struct sk_security_struct *sksec = sk->sk_security;
4281
4282 *secid = sksec->sid;
4283 }
4284 }
4285
4286 static void selinux_sock_graft(struct sock *sk, struct socket *parent)
4287 {
4288 struct inode_security_struct *isec = SOCK_INODE(parent)->i_security;
4289 struct sk_security_struct *sksec = sk->sk_security;
4290
4291 if (sk->sk_family == PF_INET || sk->sk_family == PF_INET6 ||
4292 sk->sk_family == PF_UNIX)
4293 isec->sid = sksec->sid;
4294 sksec->sclass = isec->sclass;
4295 }
4296
4297 static int selinux_inet_conn_request(struct sock *sk, struct sk_buff *skb,
4298 struct request_sock *req)
4299 {
4300 struct sk_security_struct *sksec = sk->sk_security;
4301 int err;
4302 u16 family = sk->sk_family;
4303 u32 newsid;
4304 u32 peersid;
4305
4306 /* handle mapped IPv4 packets arriving via IPv6 sockets */
4307 if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
4308 family = PF_INET;
4309
4310 err = selinux_skb_peerlbl_sid(skb, family, &peersid);
4311 if (err)
4312 return err;
4313 if (peersid == SECSID_NULL) {
4314 req->secid = sksec->sid;
4315 req->peer_secid = SECSID_NULL;
4316 } else {
4317 err = security_sid_mls_copy(sksec->sid, peersid, &newsid);
4318 if (err)
4319 return err;
4320 req->secid = newsid;
4321 req->peer_secid = peersid;
4322 }
4323
4324 return selinux_netlbl_inet_conn_request(req, family);
4325 }
4326
4327 static void selinux_inet_csk_clone(struct sock *newsk,
4328 const struct request_sock *req)
4329 {
4330 struct sk_security_struct *newsksec = newsk->sk_security;
4331
4332 newsksec->sid = req->secid;
4333 newsksec->peer_sid = req->peer_secid;
4334 /* NOTE: Ideally, we should also get the isec->sid for the
4335 new socket in sync, but we don't have the isec available yet.
4336 So we will wait until sock_graft to do it, by which
4337 time it will have been created and available. */
4338
4339 /* We don't need to take any sort of lock here as we are the only
4340 * thread with access to newsksec */
4341 selinux_netlbl_inet_csk_clone(newsk, req->rsk_ops->family);
4342 }
4343
4344 static void selinux_inet_conn_established(struct sock *sk, struct sk_buff *skb)
4345 {
4346 u16 family = sk->sk_family;
4347 struct sk_security_struct *sksec = sk->sk_security;
4348
4349 /* handle mapped IPv4 packets arriving via IPv6 sockets */
4350 if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
4351 family = PF_INET;
4352
4353 selinux_skb_peerlbl_sid(skb, family, &sksec->peer_sid);
4354 }
4355
4356 static int selinux_secmark_relabel_packet(u32 sid)
4357 {
4358 const struct task_security_struct *__tsec;
4359 u32 tsid;
4360
4361 __tsec = current_security();
4362 tsid = __tsec->sid;
4363
4364 return avc_has_perm(tsid, sid, SECCLASS_PACKET, PACKET__RELABELTO, NULL);
4365 }
4366
4367 static void selinux_secmark_refcount_inc(void)
4368 {
4369 atomic_inc(&selinux_secmark_refcount);
4370 }
4371
4372 static void selinux_secmark_refcount_dec(void)
4373 {
4374 atomic_dec(&selinux_secmark_refcount);
4375 }
4376
4377 static void selinux_req_classify_flow(const struct request_sock *req,
4378 struct flowi *fl)
4379 {
4380 fl->flowi_secid = req->secid;
4381 }
4382
4383 static int selinux_tun_dev_create(void)
4384 {
4385 u32 sid = current_sid();
4386
4387 /* we aren't taking into account the "sockcreate" SID since the socket
4388 * that is being created here is not a socket in the traditional sense,
4389 * instead it is a private sock, accessible only to the kernel, and
4390 * representing a wide range of network traffic spanning multiple
4391 * connections unlike traditional sockets - check the TUN driver to
4392 * get a better understanding of why this socket is special */
4393
4394 return avc_has_perm(sid, sid, SECCLASS_TUN_SOCKET, TUN_SOCKET__CREATE,
4395 NULL);
4396 }
4397
4398 static void selinux_tun_dev_post_create(struct sock *sk)
4399 {
4400 struct sk_security_struct *sksec = sk->sk_security;
4401
4402 /* we don't currently perform any NetLabel based labeling here and it
4403 * isn't clear that we would want to do so anyway; while we could apply
4404 * labeling without the support of the TUN user the resulting labeled
4405 * traffic from the other end of the connection would almost certainly
4406 * cause confusion to the TUN user that had no idea network labeling
4407 * protocols were being used */
4408
4409 /* see the comments in selinux_tun_dev_create() about why we don't use
4410 * the sockcreate SID here */
4411
4412 sksec->sid = current_sid();
4413 sksec->sclass = SECCLASS_TUN_SOCKET;
4414 }
4415
4416 static int selinux_tun_dev_attach(struct sock *sk)
4417 {
4418 struct sk_security_struct *sksec = sk->sk_security;
4419 u32 sid = current_sid();
4420 int err;
4421
4422 err = avc_has_perm(sid, sksec->sid, SECCLASS_TUN_SOCKET,
4423 TUN_SOCKET__RELABELFROM, NULL);
4424 if (err)
4425 return err;
4426 err = avc_has_perm(sid, sid, SECCLASS_TUN_SOCKET,
4427 TUN_SOCKET__RELABELTO, NULL);
4428 if (err)
4429 return err;
4430
4431 sksec->sid = sid;
4432
4433 return 0;
4434 }
4435
4436 static int selinux_nlmsg_perm(struct sock *sk, struct sk_buff *skb)
4437 {
4438 int err = 0;
4439 u32 perm;
4440 struct nlmsghdr *nlh;
4441 struct sk_security_struct *sksec = sk->sk_security;
4442
4443 if (skb->len < NLMSG_SPACE(0)) {
4444 err = -EINVAL;
4445 goto out;
4446 }
4447 nlh = nlmsg_hdr(skb);
4448
4449 err = selinux_nlmsg_lookup(sksec->sclass, nlh->nlmsg_type, &perm);
4450 if (err) {
4451 if (err == -EINVAL) {
4452 audit_log(current->audit_context, GFP_KERNEL, AUDIT_SELINUX_ERR,
4453 "SELinux: unrecognized netlink message"
4454 " type=%hu for sclass=%hu\n",
4455 nlh->nlmsg_type, sksec->sclass);
4456 if (!selinux_enforcing || security_get_allow_unknown())
4457 err = 0;
4458 }
4459
4460 /* Ignore */
4461 if (err == -ENOENT)
4462 err = 0;
4463 goto out;
4464 }
4465
4466 err = sock_has_perm(current, sk, perm);
4467 out:
4468 return err;
4469 }
4470
4471 #ifdef CONFIG_NETFILTER
4472
4473 static unsigned int selinux_ip_forward(struct sk_buff *skb, int ifindex,
4474 u16 family)
4475 {
4476 int err;
4477 char *addrp;
4478 u32 peer_sid;
4479 struct common_audit_data ad;
4480 u8 secmark_active;
4481 u8 netlbl_active;
4482 u8 peerlbl_active;
4483
4484 if (!selinux_policycap_netpeer)
4485 return NF_ACCEPT;
4486
4487 secmark_active = selinux_secmark_enabled();
4488 netlbl_active = netlbl_enabled();
4489 peerlbl_active = netlbl_active || selinux_xfrm_enabled();
4490 if (!secmark_active && !peerlbl_active)
4491 return NF_ACCEPT;
4492
4493 if (selinux_skb_peerlbl_sid(skb, family, &peer_sid) != 0)
4494 return NF_DROP;
4495
4496 COMMON_AUDIT_DATA_INIT(&ad, NET);
4497 ad.u.net.netif = ifindex;
4498 ad.u.net.family = family;
4499 if (selinux_parse_skb(skb, &ad, &addrp, 1, NULL) != 0)
4500 return NF_DROP;
4501
4502 if (peerlbl_active) {
4503 err = selinux_inet_sys_rcv_skb(ifindex, addrp, family,
4504 peer_sid, &ad);
4505 if (err) {
4506 selinux_netlbl_err(skb, err, 1);
4507 return NF_DROP;
4508 }
4509 }
4510
4511 if (secmark_active)
4512 if (avc_has_perm(peer_sid, skb->secmark,
4513 SECCLASS_PACKET, PACKET__FORWARD_IN, &ad))
4514 return NF_DROP;
4515
4516 if (netlbl_active)
4517 /* we do this in the FORWARD path and not the POST_ROUTING
4518 * path because we want to make sure we apply the necessary
4519 * labeling before IPsec is applied so we can leverage AH
4520 * protection */
4521 if (selinux_netlbl_skbuff_setsid(skb, family, peer_sid) != 0)
4522 return NF_DROP;
4523
4524 return NF_ACCEPT;
4525 }
4526
4527 static unsigned int selinux_ipv4_forward(unsigned int hooknum,
4528 struct sk_buff *skb,
4529 const struct net_device *in,
4530 const struct net_device *out,
4531 int (*okfn)(struct sk_buff *))
4532 {
4533 return selinux_ip_forward(skb, in->ifindex, PF_INET);
4534 }
4535
4536 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
4537 static unsigned int selinux_ipv6_forward(unsigned int hooknum,
4538 struct sk_buff *skb,
4539 const struct net_device *in,
4540 const struct net_device *out,
4541 int (*okfn)(struct sk_buff *))
4542 {
4543 return selinux_ip_forward(skb, in->ifindex, PF_INET6);
4544 }
4545 #endif /* IPV6 */
4546
4547 static unsigned int selinux_ip_output(struct sk_buff *skb,
4548 u16 family)
4549 {
4550 u32 sid;
4551
4552 if (!netlbl_enabled())
4553 return NF_ACCEPT;
4554
4555 /* we do this in the LOCAL_OUT path and not the POST_ROUTING path
4556 * because we want to make sure we apply the necessary labeling
4557 * before IPsec is applied so we can leverage AH protection */
4558 if (skb->sk) {
4559 struct sk_security_struct *sksec = skb->sk->sk_security;
4560 sid = sksec->sid;
4561 } else
4562 sid = SECINITSID_KERNEL;
4563 if (selinux_netlbl_skbuff_setsid(skb, family, sid) != 0)
4564 return NF_DROP;
4565
4566 return NF_ACCEPT;
4567 }
4568
4569 static unsigned int selinux_ipv4_output(unsigned int hooknum,
4570 struct sk_buff *skb,
4571 const struct net_device *in,
4572 const struct net_device *out,
4573 int (*okfn)(struct sk_buff *))
4574 {
4575 return selinux_ip_output(skb, PF_INET);
4576 }
4577
4578 static unsigned int selinux_ip_postroute_compat(struct sk_buff *skb,
4579 int ifindex,
4580 u16 family)
4581 {
4582 struct sock *sk = skb->sk;
4583 struct sk_security_struct *sksec;
4584 struct common_audit_data ad;
4585 char *addrp;
4586 u8 proto;
4587
4588 if (sk == NULL)
4589 return NF_ACCEPT;
4590 sksec = sk->sk_security;
4591
4592 COMMON_AUDIT_DATA_INIT(&ad, NET);
4593 ad.u.net.netif = ifindex;
4594 ad.u.net.family = family;
4595 if (selinux_parse_skb(skb, &ad, &addrp, 0, &proto))
4596 return NF_DROP;
4597
4598 if (selinux_secmark_enabled())
4599 if (avc_has_perm(sksec->sid, skb->secmark,
4600 SECCLASS_PACKET, PACKET__SEND, &ad))
4601 return NF_DROP_ERR(-ECONNREFUSED);
4602
4603 if (selinux_xfrm_postroute_last(sksec->sid, skb, &ad, proto))
4604 return NF_DROP_ERR(-ECONNREFUSED);
4605
4606 return NF_ACCEPT;
4607 }
4608
4609 static unsigned int selinux_ip_postroute(struct sk_buff *skb, int ifindex,
4610 u16 family)
4611 {
4612 u32 secmark_perm;
4613 u32 peer_sid;
4614 struct sock *sk;
4615 struct common_audit_data ad;
4616 char *addrp;
4617 u8 secmark_active;
4618 u8 peerlbl_active;
4619
4620 /* If any sort of compatibility mode is enabled then handoff processing
4621 * to the selinux_ip_postroute_compat() function to deal with the
4622 * special handling. We do this in an attempt to keep this function
4623 * as fast and as clean as possible. */
4624 if (!selinux_policycap_netpeer)
4625 return selinux_ip_postroute_compat(skb, ifindex, family);
4626 #ifdef CONFIG_XFRM
4627 /* If skb->dst->xfrm is non-NULL then the packet is undergoing an IPsec
4628 * packet transformation so allow the packet to pass without any checks
4629 * since we'll have another chance to perform access control checks
4630 * when the packet is on it's final way out.
4631 * NOTE: there appear to be some IPv6 multicast cases where skb->dst
4632 * is NULL, in this case go ahead and apply access control. */
4633 if (skb_dst(skb) != NULL && skb_dst(skb)->xfrm != NULL)
4634 return NF_ACCEPT;
4635 #endif
4636 secmark_active = selinux_secmark_enabled();
4637 peerlbl_active = netlbl_enabled() || selinux_xfrm_enabled();
4638 if (!secmark_active && !peerlbl_active)
4639 return NF_ACCEPT;
4640
4641 /* if the packet is being forwarded then get the peer label from the
4642 * packet itself; otherwise check to see if it is from a local
4643 * application or the kernel, if from an application get the peer label
4644 * from the sending socket, otherwise use the kernel's sid */
4645 sk = skb->sk;
4646 if (sk == NULL) {
4647 if (skb->skb_iif) {
4648 secmark_perm = PACKET__FORWARD_OUT;
4649 if (selinux_skb_peerlbl_sid(skb, family, &peer_sid))
4650 return NF_DROP;
4651 } else {
4652 secmark_perm = PACKET__SEND;
4653 peer_sid = SECINITSID_KERNEL;
4654 }
4655 } else {
4656 struct sk_security_struct *sksec = sk->sk_security;
4657 peer_sid = sksec->sid;
4658 secmark_perm = PACKET__SEND;
4659 }
4660
4661 COMMON_AUDIT_DATA_INIT(&ad, NET);
4662 ad.u.net.netif = ifindex;
4663 ad.u.net.family = family;
4664 if (selinux_parse_skb(skb, &ad, &addrp, 0, NULL))
4665 return NF_DROP;
4666
4667 if (secmark_active)
4668 if (avc_has_perm(peer_sid, skb->secmark,
4669 SECCLASS_PACKET, secmark_perm, &ad))
4670 return NF_DROP_ERR(-ECONNREFUSED);
4671
4672 if (peerlbl_active) {
4673 u32 if_sid;
4674 u32 node_sid;
4675
4676 if (sel_netif_sid(ifindex, &if_sid))
4677 return NF_DROP;
4678 if (avc_has_perm(peer_sid, if_sid,
4679 SECCLASS_NETIF, NETIF__EGRESS, &ad))
4680 return NF_DROP_ERR(-ECONNREFUSED);
4681
4682 if (sel_netnode_sid(addrp, family, &node_sid))
4683 return NF_DROP;
4684 if (avc_has_perm(peer_sid, node_sid,
4685 SECCLASS_NODE, NODE__SENDTO, &ad))
4686 return NF_DROP_ERR(-ECONNREFUSED);
4687 }
4688
4689 return NF_ACCEPT;
4690 }
4691
4692 static unsigned int selinux_ipv4_postroute(unsigned int hooknum,
4693 struct sk_buff *skb,
4694 const struct net_device *in,
4695 const struct net_device *out,
4696 int (*okfn)(struct sk_buff *))
4697 {
4698 return selinux_ip_postroute(skb, out->ifindex, PF_INET);
4699 }
4700
4701 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
4702 static unsigned int selinux_ipv6_postroute(unsigned int hooknum,
4703 struct sk_buff *skb,
4704 const struct net_device *in,
4705 const struct net_device *out,
4706 int (*okfn)(struct sk_buff *))
4707 {
4708 return selinux_ip_postroute(skb, out->ifindex, PF_INET6);
4709 }
4710 #endif /* IPV6 */
4711
4712 #endif /* CONFIG_NETFILTER */
4713
4714 static int selinux_netlink_send(struct sock *sk, struct sk_buff *skb)
4715 {
4716 int err;
4717
4718 err = cap_netlink_send(sk, skb);
4719 if (err)
4720 return err;
4721
4722 return selinux_nlmsg_perm(sk, skb);
4723 }
4724
4725 static int selinux_netlink_recv(struct sk_buff *skb, int capability)
4726 {
4727 int err;
4728 struct common_audit_data ad;
4729 u32 sid;
4730
4731 err = cap_netlink_recv(skb, capability);
4732 if (err)
4733 return err;
4734
4735 COMMON_AUDIT_DATA_INIT(&ad, CAP);
4736 ad.u.cap = capability;
4737
4738 security_task_getsecid(current, &sid);
4739 return avc_has_perm(sid, sid, SECCLASS_CAPABILITY,
4740 CAP_TO_MASK(capability), &ad);
4741 }
4742
4743 static int ipc_alloc_security(struct task_struct *task,
4744 struct kern_ipc_perm *perm,
4745 u16 sclass)
4746 {
4747 struct ipc_security_struct *isec;
4748 u32 sid;
4749
4750 isec = kzalloc(sizeof(struct ipc_security_struct), GFP_KERNEL);
4751 if (!isec)
4752 return -ENOMEM;
4753
4754 sid = task_sid(task);
4755 isec->sclass = sclass;
4756 isec->sid = sid;
4757 perm->security = isec;
4758
4759 return 0;
4760 }
4761
4762 static void ipc_free_security(struct kern_ipc_perm *perm)
4763 {
4764 struct ipc_security_struct *isec = perm->security;
4765 perm->security = NULL;
4766 kfree(isec);
4767 }
4768
4769 static int msg_msg_alloc_security(struct msg_msg *msg)
4770 {
4771 struct msg_security_struct *msec;
4772
4773 msec = kzalloc(sizeof(struct msg_security_struct), GFP_KERNEL);
4774 if (!msec)
4775 return -ENOMEM;
4776
4777 msec->sid = SECINITSID_UNLABELED;
4778 msg->security = msec;
4779
4780 return 0;
4781 }
4782
4783 static void msg_msg_free_security(struct msg_msg *msg)
4784 {
4785 struct msg_security_struct *msec = msg->security;
4786
4787 msg->security = NULL;
4788 kfree(msec);
4789 }
4790
4791 static int ipc_has_perm(struct kern_ipc_perm *ipc_perms,
4792 u32 perms)
4793 {
4794 struct ipc_security_struct *isec;
4795 struct common_audit_data ad;
4796 u32 sid = current_sid();
4797
4798 isec = ipc_perms->security;
4799
4800 COMMON_AUDIT_DATA_INIT(&ad, IPC);
4801 ad.u.ipc_id = ipc_perms->key;
4802
4803 return avc_has_perm(sid, isec->sid, isec->sclass, perms, &ad);
4804 }
4805
4806 static int selinux_msg_msg_alloc_security(struct msg_msg *msg)
4807 {
4808 return msg_msg_alloc_security(msg);
4809 }
4810
4811 static void selinux_msg_msg_free_security(struct msg_msg *msg)
4812 {
4813 msg_msg_free_security(msg);
4814 }
4815
4816 /* message queue security operations */
4817 static int selinux_msg_queue_alloc_security(struct msg_queue *msq)
4818 {
4819 struct ipc_security_struct *isec;
4820 struct common_audit_data ad;
4821 u32 sid = current_sid();
4822 int rc;
4823
4824 rc = ipc_alloc_security(current, &msq->q_perm, SECCLASS_MSGQ);
4825 if (rc)
4826 return rc;
4827
4828 isec = msq->q_perm.security;
4829
4830 COMMON_AUDIT_DATA_INIT(&ad, IPC);
4831 ad.u.ipc_id = msq->q_perm.key;
4832
4833 rc = avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
4834 MSGQ__CREATE, &ad);
4835 if (rc) {
4836 ipc_free_security(&msq->q_perm);
4837 return rc;
4838 }
4839 return 0;
4840 }
4841
4842 static void selinux_msg_queue_free_security(struct msg_queue *msq)
4843 {
4844 ipc_free_security(&msq->q_perm);
4845 }
4846
4847 static int selinux_msg_queue_associate(struct msg_queue *msq, int msqflg)
4848 {
4849 struct ipc_security_struct *isec;
4850 struct common_audit_data ad;
4851 u32 sid = current_sid();
4852
4853 isec = msq->q_perm.security;
4854
4855 COMMON_AUDIT_DATA_INIT(&ad, IPC);
4856 ad.u.ipc_id = msq->q_perm.key;
4857
4858 return avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
4859 MSGQ__ASSOCIATE, &ad);
4860 }
4861
4862 static int selinux_msg_queue_msgctl(struct msg_queue *msq, int cmd)
4863 {
4864 int err;
4865 int perms;
4866
4867 switch (cmd) {
4868 case IPC_INFO:
4869 case MSG_INFO:
4870 /* No specific object, just general system-wide information. */
4871 return task_has_system(current, SYSTEM__IPC_INFO);
4872 case IPC_STAT:
4873 case MSG_STAT:
4874 perms = MSGQ__GETATTR | MSGQ__ASSOCIATE;
4875 break;
4876 case IPC_SET:
4877 perms = MSGQ__SETATTR;
4878 break;
4879 case IPC_RMID:
4880 perms = MSGQ__DESTROY;
4881 break;
4882 default:
4883 return 0;
4884 }
4885
4886 err = ipc_has_perm(&msq->q_perm, perms);
4887 return err;
4888 }
4889
4890 static int selinux_msg_queue_msgsnd(struct msg_queue *msq, struct msg_msg *msg, int msqflg)
4891 {
4892 struct ipc_security_struct *isec;
4893 struct msg_security_struct *msec;
4894 struct common_audit_data ad;
4895 u32 sid = current_sid();
4896 int rc;
4897
4898 isec = msq->q_perm.security;
4899 msec = msg->security;
4900
4901 /*
4902 * First time through, need to assign label to the message
4903 */
4904 if (msec->sid == SECINITSID_UNLABELED) {
4905 /*
4906 * Compute new sid based on current process and
4907 * message queue this message will be stored in
4908 */
4909 rc = security_transition_sid(sid, isec->sid, SECCLASS_MSG,
4910 NULL, &msec->sid);
4911 if (rc)
4912 return rc;
4913 }
4914
4915 COMMON_AUDIT_DATA_INIT(&ad, IPC);
4916 ad.u.ipc_id = msq->q_perm.key;
4917
4918 /* Can this process write to the queue? */
4919 rc = avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
4920 MSGQ__WRITE, &ad);
4921 if (!rc)
4922 /* Can this process send the message */
4923 rc = avc_has_perm(sid, msec->sid, SECCLASS_MSG,
4924 MSG__SEND, &ad);
4925 if (!rc)
4926 /* Can the message be put in the queue? */
4927 rc = avc_has_perm(msec->sid, isec->sid, SECCLASS_MSGQ,
4928 MSGQ__ENQUEUE, &ad);
4929
4930 return rc;
4931 }
4932
4933 static int selinux_msg_queue_msgrcv(struct msg_queue *msq, struct msg_msg *msg,
4934 struct task_struct *target,
4935 long type, int mode)
4936 {
4937 struct ipc_security_struct *isec;
4938 struct msg_security_struct *msec;
4939 struct common_audit_data ad;
4940 u32 sid = task_sid(target);
4941 int rc;
4942
4943 isec = msq->q_perm.security;
4944 msec = msg->security;
4945
4946 COMMON_AUDIT_DATA_INIT(&ad, IPC);
4947 ad.u.ipc_id = msq->q_perm.key;
4948
4949 rc = avc_has_perm(sid, isec->sid,
4950 SECCLASS_MSGQ, MSGQ__READ, &ad);
4951 if (!rc)
4952 rc = avc_has_perm(sid, msec->sid,
4953 SECCLASS_MSG, MSG__RECEIVE, &ad);
4954 return rc;
4955 }
4956
4957 /* Shared Memory security operations */
4958 static int selinux_shm_alloc_security(struct shmid_kernel *shp)
4959 {
4960 struct ipc_security_struct *isec;
4961 struct common_audit_data ad;
4962 u32 sid = current_sid();
4963 int rc;
4964
4965 rc = ipc_alloc_security(current, &shp->shm_perm, SECCLASS_SHM);
4966 if (rc)
4967 return rc;
4968
4969 isec = shp->shm_perm.security;
4970
4971 COMMON_AUDIT_DATA_INIT(&ad, IPC);
4972 ad.u.ipc_id = shp->shm_perm.key;
4973
4974 rc = avc_has_perm(sid, isec->sid, SECCLASS_SHM,
4975 SHM__CREATE, &ad);
4976 if (rc) {
4977 ipc_free_security(&shp->shm_perm);
4978 return rc;
4979 }
4980 return 0;
4981 }
4982
4983 static void selinux_shm_free_security(struct shmid_kernel *shp)
4984 {
4985 ipc_free_security(&shp->shm_perm);
4986 }
4987
4988 static int selinux_shm_associate(struct shmid_kernel *shp, int shmflg)
4989 {
4990 struct ipc_security_struct *isec;
4991 struct common_audit_data ad;
4992 u32 sid = current_sid();
4993
4994 isec = shp->shm_perm.security;
4995
4996 COMMON_AUDIT_DATA_INIT(&ad, IPC);
4997 ad.u.ipc_id = shp->shm_perm.key;
4998
4999 return avc_has_perm(sid, isec->sid, SECCLASS_SHM,
5000 SHM__ASSOCIATE, &ad);
5001 }
5002
5003 /* Note, at this point, shp is locked down */
5004 static int selinux_shm_shmctl(struct shmid_kernel *shp, int cmd)
5005 {
5006 int perms;
5007 int err;
5008
5009 switch (cmd) {
5010 case IPC_INFO:
5011 case SHM_INFO:
5012 /* No specific object, just general system-wide information. */
5013 return task_has_system(current, SYSTEM__IPC_INFO);
5014 case IPC_STAT:
5015 case SHM_STAT:
5016 perms = SHM__GETATTR | SHM__ASSOCIATE;
5017 break;
5018 case IPC_SET:
5019 perms = SHM__SETATTR;
5020 break;
5021 case SHM_LOCK:
5022 case SHM_UNLOCK:
5023 perms = SHM__LOCK;
5024 break;
5025 case IPC_RMID:
5026 perms = SHM__DESTROY;
5027 break;
5028 default:
5029 return 0;
5030 }
5031
5032 err = ipc_has_perm(&shp->shm_perm, perms);
5033 return err;
5034 }
5035
5036 static int selinux_shm_shmat(struct shmid_kernel *shp,
5037 char __user *shmaddr, int shmflg)
5038 {
5039 u32 perms;
5040
5041 if (shmflg & SHM_RDONLY)
5042 perms = SHM__READ;
5043 else
5044 perms = SHM__READ | SHM__WRITE;
5045
5046 return ipc_has_perm(&shp->shm_perm, perms);
5047 }
5048
5049 /* Semaphore security operations */
5050 static int selinux_sem_alloc_security(struct sem_array *sma)
5051 {
5052 struct ipc_security_struct *isec;
5053 struct common_audit_data ad;
5054 u32 sid = current_sid();
5055 int rc;
5056
5057 rc = ipc_alloc_security(current, &sma->sem_perm, SECCLASS_SEM);
5058 if (rc)
5059 return rc;
5060
5061 isec = sma->sem_perm.security;
5062
5063 COMMON_AUDIT_DATA_INIT(&ad, IPC);
5064 ad.u.ipc_id = sma->sem_perm.key;
5065
5066 rc = avc_has_perm(sid, isec->sid, SECCLASS_SEM,
5067 SEM__CREATE, &ad);
5068 if (rc) {
5069 ipc_free_security(&sma->sem_perm);
5070 return rc;
5071 }
5072 return 0;
5073 }
5074
5075 static void selinux_sem_free_security(struct sem_array *sma)
5076 {
5077 ipc_free_security(&sma->sem_perm);
5078 }
5079
5080 static int selinux_sem_associate(struct sem_array *sma, int semflg)
5081 {
5082 struct ipc_security_struct *isec;
5083 struct common_audit_data ad;
5084 u32 sid = current_sid();
5085
5086 isec = sma->sem_perm.security;
5087
5088 COMMON_AUDIT_DATA_INIT(&ad, IPC);
5089 ad.u.ipc_id = sma->sem_perm.key;
5090
5091 return avc_has_perm(sid, isec->sid, SECCLASS_SEM,
5092 SEM__ASSOCIATE, &ad);
5093 }
5094
5095 /* Note, at this point, sma is locked down */
5096 static int selinux_sem_semctl(struct sem_array *sma, int cmd)
5097 {
5098 int err;
5099 u32 perms;
5100
5101 switch (cmd) {
5102 case IPC_INFO:
5103 case SEM_INFO:
5104 /* No specific object, just general system-wide information. */
5105 return task_has_system(current, SYSTEM__IPC_INFO);
5106 case GETPID:
5107 case GETNCNT:
5108 case GETZCNT:
5109 perms = SEM__GETATTR;
5110 break;
5111 case GETVAL:
5112 case GETALL:
5113 perms = SEM__READ;
5114 break;
5115 case SETVAL:
5116 case SETALL:
5117 perms = SEM__WRITE;
5118 break;
5119 case IPC_RMID:
5120 perms = SEM__DESTROY;
5121 break;
5122 case IPC_SET:
5123 perms = SEM__SETATTR;
5124 break;
5125 case IPC_STAT:
5126 case SEM_STAT:
5127 perms = SEM__GETATTR | SEM__ASSOCIATE;
5128 break;
5129 default:
5130 return 0;
5131 }
5132
5133 err = ipc_has_perm(&sma->sem_perm, perms);
5134 return err;
5135 }
5136
5137 static int selinux_sem_semop(struct sem_array *sma,
5138 struct sembuf *sops, unsigned nsops, int alter)
5139 {
5140 u32 perms;
5141
5142 if (alter)
5143 perms = SEM__READ | SEM__WRITE;
5144 else
5145 perms = SEM__READ;
5146
5147 return ipc_has_perm(&sma->sem_perm, perms);
5148 }
5149
5150 static int selinux_ipc_permission(struct kern_ipc_perm *ipcp, short flag)
5151 {
5152 u32 av = 0;
5153
5154 av = 0;
5155 if (flag & S_IRUGO)
5156 av |= IPC__UNIX_READ;
5157 if (flag & S_IWUGO)
5158 av |= IPC__UNIX_WRITE;
5159
5160 if (av == 0)
5161 return 0;
5162
5163 return ipc_has_perm(ipcp, av);
5164 }
5165
5166 static void selinux_ipc_getsecid(struct kern_ipc_perm *ipcp, u32 *secid)
5167 {
5168 struct ipc_security_struct *isec = ipcp->security;
5169 *secid = isec->sid;
5170 }
5171
5172 static void selinux_d_instantiate(struct dentry *dentry, struct inode *inode)
5173 {
5174 if (inode)
5175 inode_doinit_with_dentry(inode, dentry);
5176 }
5177
5178 static int selinux_getprocattr(struct task_struct *p,
5179 char *name, char **value)
5180 {
5181 const struct task_security_struct *__tsec;
5182 u32 sid;
5183 int error;
5184 unsigned len;
5185
5186 if (current != p) {
5187 error = current_has_perm(p, PROCESS__GETATTR);
5188 if (error)
5189 return error;
5190 }
5191
5192 rcu_read_lock();
5193 __tsec = __task_cred(p)->security;
5194
5195 if (!strcmp(name, "current"))
5196 sid = __tsec->sid;
5197 else if (!strcmp(name, "prev"))
5198 sid = __tsec->osid;
5199 else if (!strcmp(name, "exec"))
5200 sid = __tsec->exec_sid;
5201 else if (!strcmp(name, "fscreate"))
5202 sid = __tsec->create_sid;
5203 else if (!strcmp(name, "keycreate"))
5204 sid = __tsec->keycreate_sid;
5205 else if (!strcmp(name, "sockcreate"))
5206 sid = __tsec->sockcreate_sid;
5207 else
5208 goto invalid;
5209 rcu_read_unlock();
5210
5211 if (!sid)
5212 return 0;
5213
5214 error = security_sid_to_context(sid, value, &len);
5215 if (error)
5216 return error;
5217 return len;
5218
5219 invalid:
5220 rcu_read_unlock();
5221 return -EINVAL;
5222 }
5223
5224 static int selinux_setprocattr(struct task_struct *p,
5225 char *name, void *value, size_t size)
5226 {
5227 struct task_security_struct *tsec;
5228 struct task_struct *tracer;
5229 struct cred *new;
5230 u32 sid = 0, ptsid;
5231 int error;
5232 char *str = value;
5233
5234 if (current != p) {
5235 /* SELinux only allows a process to change its own
5236 security attributes. */
5237 return -EACCES;
5238 }
5239
5240 /*
5241 * Basic control over ability to set these attributes at all.
5242 * current == p, but we'll pass them separately in case the
5243 * above restriction is ever removed.
5244 */
5245 if (!strcmp(name, "exec"))
5246 error = current_has_perm(p, PROCESS__SETEXEC);
5247 else if (!strcmp(name, "fscreate"))
5248 error = current_has_perm(p, PROCESS__SETFSCREATE);
5249 else if (!strcmp(name, "keycreate"))
5250 error = current_has_perm(p, PROCESS__SETKEYCREATE);
5251 else if (!strcmp(name, "sockcreate"))
5252 error = current_has_perm(p, PROCESS__SETSOCKCREATE);
5253 else if (!strcmp(name, "current"))
5254 error = current_has_perm(p, PROCESS__SETCURRENT);
5255 else
5256 error = -EINVAL;
5257 if (error)
5258 return error;
5259
5260 /* Obtain a SID for the context, if one was specified. */
5261 if (size && str[1] && str[1] != '\n') {
5262 if (str[size-1] == '\n') {
5263 str[size-1] = 0;
5264 size--;
5265 }
5266 error = security_context_to_sid(value, size, &sid);
5267 if (error == -EINVAL && !strcmp(name, "fscreate")) {
5268 if (!capable(CAP_MAC_ADMIN))
5269 return error;
5270 error = security_context_to_sid_force(value, size,
5271 &sid);
5272 }
5273 if (error)
5274 return error;
5275 }
5276
5277 new = prepare_creds();
5278 if (!new)
5279 return -ENOMEM;
5280
5281 /* Permission checking based on the specified context is
5282 performed during the actual operation (execve,
5283 open/mkdir/...), when we know the full context of the
5284 operation. See selinux_bprm_set_creds for the execve
5285 checks and may_create for the file creation checks. The
5286 operation will then fail if the context is not permitted. */
5287 tsec = new->security;
5288 if (!strcmp(name, "exec")) {
5289 tsec->exec_sid = sid;
5290 } else if (!strcmp(name, "fscreate")) {
5291 tsec->create_sid = sid;
5292 } else if (!strcmp(name, "keycreate")) {
5293 error = may_create_key(sid, p);
5294 if (error)
5295 goto abort_change;
5296 tsec->keycreate_sid = sid;
5297 } else if (!strcmp(name, "sockcreate")) {
5298 tsec->sockcreate_sid = sid;
5299 } else if (!strcmp(name, "current")) {
5300 error = -EINVAL;
5301 if (sid == 0)
5302 goto abort_change;
5303
5304 /* Only allow single threaded processes to change context */
5305 error = -EPERM;
5306 if (!current_is_single_threaded()) {
5307 error = security_bounded_transition(tsec->sid, sid);
5308 if (error)
5309 goto abort_change;
5310 }
5311
5312 /* Check permissions for the transition. */
5313 error = avc_has_perm(tsec->sid, sid, SECCLASS_PROCESS,
5314 PROCESS__DYNTRANSITION, NULL);
5315 if (error)
5316 goto abort_change;
5317
5318 /* Check for ptracing, and update the task SID if ok.
5319 Otherwise, leave SID unchanged and fail. */
5320 ptsid = 0;
5321 task_lock(p);
5322 tracer = ptrace_parent(p);
5323 if (tracer)
5324 ptsid = task_sid(tracer);
5325 task_unlock(p);
5326
5327 if (tracer) {
5328 error = avc_has_perm(ptsid, sid, SECCLASS_PROCESS,
5329 PROCESS__PTRACE, NULL);
5330 if (error)
5331 goto abort_change;
5332 }
5333
5334 tsec->sid = sid;
5335 } else {
5336 error = -EINVAL;
5337 goto abort_change;
5338 }
5339
5340 commit_creds(new);
5341 return size;
5342
5343 abort_change:
5344 abort_creds(new);
5345 return error;
5346 }
5347
5348 static int selinux_secid_to_secctx(u32 secid, char **secdata, u32 *seclen)
5349 {
5350 return security_sid_to_context(secid, secdata, seclen);
5351 }
5352
5353 static int selinux_secctx_to_secid(const char *secdata, u32 seclen, u32 *secid)
5354 {
5355 return security_context_to_sid(secdata, seclen, secid);
5356 }
5357
5358 static void selinux_release_secctx(char *secdata, u32 seclen)
5359 {
5360 kfree(secdata);
5361 }
5362
5363 /*
5364 * called with inode->i_mutex locked
5365 */
5366 static int selinux_inode_notifysecctx(struct inode *inode, void *ctx, u32 ctxlen)
5367 {
5368 return selinux_inode_setsecurity(inode, XATTR_SELINUX_SUFFIX, ctx, ctxlen, 0);
5369 }
5370
5371 /*
5372 * called with inode->i_mutex locked
5373 */
5374 static int selinux_inode_setsecctx(struct dentry *dentry, void *ctx, u32 ctxlen)
5375 {
5376 return __vfs_setxattr_noperm(dentry, XATTR_NAME_SELINUX, ctx, ctxlen, 0);
5377 }
5378
5379 static int selinux_inode_getsecctx(struct inode *inode, void **ctx, u32 *ctxlen)
5380 {
5381 int len = 0;
5382 len = selinux_inode_getsecurity(inode, XATTR_SELINUX_SUFFIX,
5383 ctx, true);
5384 if (len < 0)
5385 return len;
5386 *ctxlen = len;
5387 return 0;
5388 }
5389 #ifdef CONFIG_KEYS
5390
5391 static int selinux_key_alloc(struct key *k, const struct cred *cred,
5392 unsigned long flags)
5393 {
5394 const struct task_security_struct *tsec;
5395 struct key_security_struct *ksec;
5396
5397 ksec = kzalloc(sizeof(struct key_security_struct), GFP_KERNEL);
5398 if (!ksec)
5399 return -ENOMEM;
5400
5401 tsec = cred->security;
5402 if (tsec->keycreate_sid)
5403 ksec->sid = tsec->keycreate_sid;
5404 else
5405 ksec->sid = tsec->sid;
5406
5407 k->security = ksec;
5408 return 0;
5409 }
5410
5411 static void selinux_key_free(struct key *k)
5412 {
5413 struct key_security_struct *ksec = k->security;
5414
5415 k->security = NULL;
5416 kfree(ksec);
5417 }
5418
5419 static int selinux_key_permission(key_ref_t key_ref,
5420 const struct cred *cred,
5421 key_perm_t perm)
5422 {
5423 struct key *key;
5424 struct key_security_struct *ksec;
5425 u32 sid;
5426
5427 /* if no specific permissions are requested, we skip the
5428 permission check. No serious, additional covert channels
5429 appear to be created. */
5430 if (perm == 0)
5431 return 0;
5432
5433 sid = cred_sid(cred);
5434
5435 key = key_ref_to_ptr(key_ref);
5436 ksec = key->security;
5437
5438 return avc_has_perm(sid, ksec->sid, SECCLASS_KEY, perm, NULL);
5439 }
5440
5441 static int selinux_key_getsecurity(struct key *key, char **_buffer)
5442 {
5443 struct key_security_struct *ksec = key->security;
5444 char *context = NULL;
5445 unsigned len;
5446 int rc;
5447
5448 rc = security_sid_to_context(ksec->sid, &context, &len);
5449 if (!rc)
5450 rc = len;
5451 *_buffer = context;
5452 return rc;
5453 }
5454
5455 #endif
5456
5457 static struct security_operations selinux_ops = {
5458 .name = "selinux",
5459
5460 .ptrace_access_check = selinux_ptrace_access_check,
5461 .ptrace_traceme = selinux_ptrace_traceme,
5462 .capget = selinux_capget,
5463 .capset = selinux_capset,
5464 .capable = selinux_capable,
5465 .quotactl = selinux_quotactl,
5466 .quota_on = selinux_quota_on,
5467 .syslog = selinux_syslog,
5468 .vm_enough_memory = selinux_vm_enough_memory,
5469
5470 .netlink_send = selinux_netlink_send,
5471 .netlink_recv = selinux_netlink_recv,
5472
5473 .bprm_set_creds = selinux_bprm_set_creds,
5474 .bprm_committing_creds = selinux_bprm_committing_creds,
5475 .bprm_committed_creds = selinux_bprm_committed_creds,
5476 .bprm_secureexec = selinux_bprm_secureexec,
5477
5478 .sb_alloc_security = selinux_sb_alloc_security,
5479 .sb_free_security = selinux_sb_free_security,
5480 .sb_copy_data = selinux_sb_copy_data,
5481 .sb_remount = selinux_sb_remount,
5482 .sb_kern_mount = selinux_sb_kern_mount,
5483 .sb_show_options = selinux_sb_show_options,
5484 .sb_statfs = selinux_sb_statfs,
5485 .sb_mount = selinux_mount,
5486 .sb_umount = selinux_umount,
5487 .sb_set_mnt_opts = selinux_set_mnt_opts,
5488 .sb_clone_mnt_opts = selinux_sb_clone_mnt_opts,
5489 .sb_parse_opts_str = selinux_parse_opts_str,
5490
5491
5492 .inode_alloc_security = selinux_inode_alloc_security,
5493 .inode_free_security = selinux_inode_free_security,
5494 .inode_init_security = selinux_inode_init_security,
5495 .inode_create = selinux_inode_create,
5496 .inode_link = selinux_inode_link,
5497 .inode_unlink = selinux_inode_unlink,
5498 .inode_symlink = selinux_inode_symlink,
5499 .inode_mkdir = selinux_inode_mkdir,
5500 .inode_rmdir = selinux_inode_rmdir,
5501 .inode_mknod = selinux_inode_mknod,
5502 .inode_rename = selinux_inode_rename,
5503 .inode_readlink = selinux_inode_readlink,
5504 .inode_follow_link = selinux_inode_follow_link,
5505 .inode_permission = selinux_inode_permission,
5506 .inode_setattr = selinux_inode_setattr,
5507 .inode_getattr = selinux_inode_getattr,
5508 .inode_setxattr = selinux_inode_setxattr,
5509 .inode_post_setxattr = selinux_inode_post_setxattr,
5510 .inode_getxattr = selinux_inode_getxattr,
5511 .inode_listxattr = selinux_inode_listxattr,
5512 .inode_removexattr = selinux_inode_removexattr,
5513 .inode_getsecurity = selinux_inode_getsecurity,
5514 .inode_setsecurity = selinux_inode_setsecurity,
5515 .inode_listsecurity = selinux_inode_listsecurity,
5516 .inode_getsecid = selinux_inode_getsecid,
5517
5518 .file_permission = selinux_file_permission,
5519 .file_alloc_security = selinux_file_alloc_security,
5520 .file_free_security = selinux_file_free_security,
5521 .file_ioctl = selinux_file_ioctl,
5522 .file_mmap = selinux_file_mmap,
5523 .file_mprotect = selinux_file_mprotect,
5524 .file_lock = selinux_file_lock,
5525 .file_fcntl = selinux_file_fcntl,
5526 .file_set_fowner = selinux_file_set_fowner,
5527 .file_send_sigiotask = selinux_file_send_sigiotask,
5528 .file_receive = selinux_file_receive,
5529
5530 .dentry_open = selinux_dentry_open,
5531
5532 .task_create = selinux_task_create,
5533 .cred_alloc_blank = selinux_cred_alloc_blank,
5534 .cred_free = selinux_cred_free,
5535 .cred_prepare = selinux_cred_prepare,
5536 .cred_transfer = selinux_cred_transfer,
5537 .kernel_act_as = selinux_kernel_act_as,
5538 .kernel_create_files_as = selinux_kernel_create_files_as,
5539 .kernel_module_request = selinux_kernel_module_request,
5540 .task_setpgid = selinux_task_setpgid,
5541 .task_getpgid = selinux_task_getpgid,
5542 .task_getsid = selinux_task_getsid,
5543 .task_getsecid = selinux_task_getsecid,
5544 .task_setnice = selinux_task_setnice,
5545 .task_setioprio = selinux_task_setioprio,
5546 .task_getioprio = selinux_task_getioprio,
5547 .task_setrlimit = selinux_task_setrlimit,
5548 .task_setscheduler = selinux_task_setscheduler,
5549 .task_getscheduler = selinux_task_getscheduler,
5550 .task_movememory = selinux_task_movememory,
5551 .task_kill = selinux_task_kill,
5552 .task_wait = selinux_task_wait,
5553 .task_to_inode = selinux_task_to_inode,
5554
5555 .ipc_permission = selinux_ipc_permission,
5556 .ipc_getsecid = selinux_ipc_getsecid,
5557
5558 .msg_msg_alloc_security = selinux_msg_msg_alloc_security,
5559 .msg_msg_free_security = selinux_msg_msg_free_security,
5560
5561 .msg_queue_alloc_security = selinux_msg_queue_alloc_security,
5562 .msg_queue_free_security = selinux_msg_queue_free_security,
5563 .msg_queue_associate = selinux_msg_queue_associate,
5564 .msg_queue_msgctl = selinux_msg_queue_msgctl,
5565 .msg_queue_msgsnd = selinux_msg_queue_msgsnd,
5566 .msg_queue_msgrcv = selinux_msg_queue_msgrcv,
5567
5568 .shm_alloc_security = selinux_shm_alloc_security,
5569 .shm_free_security = selinux_shm_free_security,
5570 .shm_associate = selinux_shm_associate,
5571 .shm_shmctl = selinux_shm_shmctl,
5572 .shm_shmat = selinux_shm_shmat,
5573
5574 .sem_alloc_security = selinux_sem_alloc_security,
5575 .sem_free_security = selinux_sem_free_security,
5576 .sem_associate = selinux_sem_associate,
5577 .sem_semctl = selinux_sem_semctl,
5578 .sem_semop = selinux_sem_semop,
5579
5580 .d_instantiate = selinux_d_instantiate,
5581
5582 .getprocattr = selinux_getprocattr,
5583 .setprocattr = selinux_setprocattr,
5584
5585 .secid_to_secctx = selinux_secid_to_secctx,
5586 .secctx_to_secid = selinux_secctx_to_secid,
5587 .release_secctx = selinux_release_secctx,
5588 .inode_notifysecctx = selinux_inode_notifysecctx,
5589 .inode_setsecctx = selinux_inode_setsecctx,
5590 .inode_getsecctx = selinux_inode_getsecctx,
5591
5592 .unix_stream_connect = selinux_socket_unix_stream_connect,
5593 .unix_may_send = selinux_socket_unix_may_send,
5594
5595 .socket_create = selinux_socket_create,
5596 .socket_post_create = selinux_socket_post_create,
5597 .socket_bind = selinux_socket_bind,
5598 .socket_connect = selinux_socket_connect,
5599 .socket_listen = selinux_socket_listen,
5600 .socket_accept = selinux_socket_accept,
5601 .socket_sendmsg = selinux_socket_sendmsg,
5602 .socket_recvmsg = selinux_socket_recvmsg,
5603 .socket_getsockname = selinux_socket_getsockname,
5604 .socket_getpeername = selinux_socket_getpeername,
5605 .socket_getsockopt = selinux_socket_getsockopt,
5606 .socket_setsockopt = selinux_socket_setsockopt,
5607 .socket_shutdown = selinux_socket_shutdown,
5608 .socket_sock_rcv_skb = selinux_socket_sock_rcv_skb,
5609 .socket_getpeersec_stream = selinux_socket_getpeersec_stream,
5610 .socket_getpeersec_dgram = selinux_socket_getpeersec_dgram,
5611 .sk_alloc_security = selinux_sk_alloc_security,
5612 .sk_free_security = selinux_sk_free_security,
5613 .sk_clone_security = selinux_sk_clone_security,
5614 .sk_getsecid = selinux_sk_getsecid,
5615 .sock_graft = selinux_sock_graft,
5616 .inet_conn_request = selinux_inet_conn_request,
5617 .inet_csk_clone = selinux_inet_csk_clone,
5618 .inet_conn_established = selinux_inet_conn_established,
5619 .secmark_relabel_packet = selinux_secmark_relabel_packet,
5620 .secmark_refcount_inc = selinux_secmark_refcount_inc,
5621 .secmark_refcount_dec = selinux_secmark_refcount_dec,
5622 .req_classify_flow = selinux_req_classify_flow,
5623 .tun_dev_create = selinux_tun_dev_create,
5624 .tun_dev_post_create = selinux_tun_dev_post_create,
5625 .tun_dev_attach = selinux_tun_dev_attach,
5626
5627 #ifdef CONFIG_SECURITY_NETWORK_XFRM
5628 .xfrm_policy_alloc_security = selinux_xfrm_policy_alloc,
5629 .xfrm_policy_clone_security = selinux_xfrm_policy_clone,
5630 .xfrm_policy_free_security = selinux_xfrm_policy_free,
5631 .xfrm_policy_delete_security = selinux_xfrm_policy_delete,
5632 .xfrm_state_alloc_security = selinux_xfrm_state_alloc,
5633 .xfrm_state_free_security = selinux_xfrm_state_free,
5634 .xfrm_state_delete_security = selinux_xfrm_state_delete,
5635 .xfrm_policy_lookup = selinux_xfrm_policy_lookup,
5636 .xfrm_state_pol_flow_match = selinux_xfrm_state_pol_flow_match,
5637 .xfrm_decode_session = selinux_xfrm_decode_session,
5638 #endif
5639
5640 #ifdef CONFIG_KEYS
5641 .key_alloc = selinux_key_alloc,
5642 .key_free = selinux_key_free,
5643 .key_permission = selinux_key_permission,
5644 .key_getsecurity = selinux_key_getsecurity,
5645 #endif
5646
5647 #ifdef CONFIG_AUDIT
5648 .audit_rule_init = selinux_audit_rule_init,
5649 .audit_rule_known = selinux_audit_rule_known,
5650 .audit_rule_match = selinux_audit_rule_match,
5651 .audit_rule_free = selinux_audit_rule_free,
5652 #endif
5653 };
5654
5655 static __init int selinux_init(void)
5656 {
5657 if (!security_module_enable(&selinux_ops)) {
5658 selinux_enabled = 0;
5659 return 0;
5660 }
5661
5662 if (!selinux_enabled) {
5663 printk(KERN_INFO "SELinux: Disabled at boot.\n");
5664 return 0;
5665 }
5666
5667 printk(KERN_INFO "SELinux: Initializing.\n");
5668
5669 /* Set the security state for the initial task. */
5670 cred_init_security();
5671
5672 default_noexec = !(VM_DATA_DEFAULT_FLAGS & VM_EXEC);
5673
5674 sel_inode_cache = kmem_cache_create("selinux_inode_security",
5675 sizeof(struct inode_security_struct),
5676 0, SLAB_PANIC, NULL);
5677 avc_init();
5678
5679 if (register_security(&selinux_ops))
5680 panic("SELinux: Unable to register with kernel.\n");
5681
5682 if (selinux_enforcing)
5683 printk(KERN_DEBUG "SELinux: Starting in enforcing mode\n");
5684 else
5685 printk(KERN_DEBUG "SELinux: Starting in permissive mode\n");
5686
5687 return 0;
5688 }
5689
5690 static void delayed_superblock_init(struct super_block *sb, void *unused)
5691 {
5692 superblock_doinit(sb, NULL);
5693 }
5694
5695 void selinux_complete_init(void)
5696 {
5697 printk(KERN_DEBUG "SELinux: Completing initialization.\n");
5698
5699 /* Set up any superblocks initialized prior to the policy load. */
5700 printk(KERN_DEBUG "SELinux: Setting up existing superblocks.\n");
5701 iterate_supers(delayed_superblock_init, NULL);
5702 }
5703
5704 /* SELinux requires early initialization in order to label
5705 all processes and objects when they are created. */
5706 security_initcall(selinux_init);
5707
5708 #if defined(CONFIG_NETFILTER)
5709
5710 static struct nf_hook_ops selinux_ipv4_ops[] = {
5711 {
5712 .hook = selinux_ipv4_postroute,
5713 .owner = THIS_MODULE,
5714 .pf = PF_INET,
5715 .hooknum = NF_INET_POST_ROUTING,
5716 .priority = NF_IP_PRI_SELINUX_LAST,
5717 },
5718 {
5719 .hook = selinux_ipv4_forward,
5720 .owner = THIS_MODULE,
5721 .pf = PF_INET,
5722 .hooknum = NF_INET_FORWARD,
5723 .priority = NF_IP_PRI_SELINUX_FIRST,
5724 },
5725 {
5726 .hook = selinux_ipv4_output,
5727 .owner = THIS_MODULE,
5728 .pf = PF_INET,
5729 .hooknum = NF_INET_LOCAL_OUT,
5730 .priority = NF_IP_PRI_SELINUX_FIRST,
5731 }
5732 };
5733
5734 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
5735
5736 static struct nf_hook_ops selinux_ipv6_ops[] = {
5737 {
5738 .hook = selinux_ipv6_postroute,
5739 .owner = THIS_MODULE,
5740 .pf = PF_INET6,
5741 .hooknum = NF_INET_POST_ROUTING,
5742 .priority = NF_IP6_PRI_SELINUX_LAST,
5743 },
5744 {
5745 .hook = selinux_ipv6_forward,
5746 .owner = THIS_MODULE,
5747 .pf = PF_INET6,
5748 .hooknum = NF_INET_FORWARD,
5749 .priority = NF_IP6_PRI_SELINUX_FIRST,
5750 }
5751 };
5752
5753 #endif /* IPV6 */
5754
5755 static int __init selinux_nf_ip_init(void)
5756 {
5757 int err = 0;
5758
5759 if (!selinux_enabled)
5760 goto out;
5761
5762 printk(KERN_DEBUG "SELinux: Registering netfilter hooks\n");
5763
5764 err = nf_register_hooks(selinux_ipv4_ops, ARRAY_SIZE(selinux_ipv4_ops));
5765 if (err)
5766 panic("SELinux: nf_register_hooks for IPv4: error %d\n", err);
5767
5768 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
5769 err = nf_register_hooks(selinux_ipv6_ops, ARRAY_SIZE(selinux_ipv6_ops));
5770 if (err)
5771 panic("SELinux: nf_register_hooks for IPv6: error %d\n", err);
5772 #endif /* IPV6 */
5773
5774 out:
5775 return err;
5776 }
5777
5778 __initcall(selinux_nf_ip_init);
5779
5780 #ifdef CONFIG_SECURITY_SELINUX_DISABLE
5781 static void selinux_nf_ip_exit(void)
5782 {
5783 printk(KERN_DEBUG "SELinux: Unregistering netfilter hooks\n");
5784
5785 nf_unregister_hooks(selinux_ipv4_ops, ARRAY_SIZE(selinux_ipv4_ops));
5786 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
5787 nf_unregister_hooks(selinux_ipv6_ops, ARRAY_SIZE(selinux_ipv6_ops));
5788 #endif /* IPV6 */
5789 }
5790 #endif
5791
5792 #else /* CONFIG_NETFILTER */
5793
5794 #ifdef CONFIG_SECURITY_SELINUX_DISABLE
5795 #define selinux_nf_ip_exit()
5796 #endif
5797
5798 #endif /* CONFIG_NETFILTER */
5799
5800 #ifdef CONFIG_SECURITY_SELINUX_DISABLE
5801 static int selinux_disabled;
5802
5803 int selinux_disable(void)
5804 {
5805 extern void exit_sel_fs(void);
5806
5807 if (ss_initialized) {
5808 /* Not permitted after initial policy load. */
5809 return -EINVAL;
5810 }
5811
5812 if (selinux_disabled) {
5813 /* Only do this once. */
5814 return -EINVAL;
5815 }
5816
5817 printk(KERN_INFO "SELinux: Disabled at runtime.\n");
5818
5819 selinux_disabled = 1;
5820 selinux_enabled = 0;
5821
5822 reset_security_ops();
5823
5824 /* Try to destroy the avc node cache */
5825 avc_disable();
5826
5827 /* Unregister netfilter hooks. */
5828 selinux_nf_ip_exit();
5829
5830 /* Unregister selinuxfs. */
5831 exit_sel_fs();
5832
5833 return 0;
5834 }
5835 #endif
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