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fs: cleanup files_lock locking
[deliverable/linux.git] / security / selinux / hooks.c
1 /*
2 * NSA Security-Enhanced Linux (SELinux) security module
3 *
4 * This file contains the SELinux hook function implementations.
5 *
6 * Authors: Stephen Smalley, <sds@epoch.ncsc.mil>
7 * Chris Vance, <cvance@nai.com>
8 * Wayne Salamon, <wsalamon@nai.com>
9 * James Morris <jmorris@redhat.com>
10 *
11 * Copyright (C) 2001,2002 Networks Associates Technology, Inc.
12 * Copyright (C) 2003-2008 Red Hat, Inc., James Morris <jmorris@redhat.com>
13 * Eric Paris <eparis@redhat.com>
14 * Copyright (C) 2004-2005 Trusted Computer Solutions, Inc.
15 * <dgoeddel@trustedcs.com>
16 * Copyright (C) 2006, 2007, 2009 Hewlett-Packard Development Company, L.P.
17 * Paul Moore <paul.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/kernel.h>
28 #include <linux/tracehook.h>
29 #include <linux/errno.h>
30 #include <linux/sched.h>
31 #include <linux/security.h>
32 #include <linux/xattr.h>
33 #include <linux/capability.h>
34 #include <linux/unistd.h>
35 #include <linux/mm.h>
36 #include <linux/mman.h>
37 #include <linux/slab.h>
38 #include <linux/pagemap.h>
39 #include <linux/swap.h>
40 #include <linux/spinlock.h>
41 #include <linux/syscalls.h>
42 #include <linux/file.h>
43 #include <linux/fdtable.h>
44 #include <linux/namei.h>
45 #include <linux/mount.h>
46 #include <linux/proc_fs.h>
47 #include <linux/netfilter_ipv4.h>
48 #include <linux/netfilter_ipv6.h>
49 #include <linux/tty.h>
50 #include <net/icmp.h>
51 #include <net/ip.h> /* for local_port_range[] */
52 #include <net/tcp.h> /* struct or_callable used in sock_rcv_skb */
53 #include <net/net_namespace.h>
54 #include <net/netlabel.h>
55 #include <linux/uaccess.h>
56 #include <asm/ioctls.h>
57 #include <asm/atomic.h>
58 #include <linux/bitops.h>
59 #include <linux/interrupt.h>
60 #include <linux/netdevice.h> /* for network interface checks */
61 #include <linux/netlink.h>
62 #include <linux/tcp.h>
63 #include <linux/udp.h>
64 #include <linux/dccp.h>
65 #include <linux/quota.h>
66 #include <linux/un.h> /* for Unix socket types */
67 #include <net/af_unix.h> /* for Unix socket types */
68 #include <linux/parser.h>
69 #include <linux/nfs_mount.h>
70 #include <net/ipv6.h>
71 #include <linux/hugetlb.h>
72 #include <linux/personality.h>
73 #include <linux/sysctl.h>
74 #include <linux/audit.h>
75 #include <linux/string.h>
76 #include <linux/selinux.h>
77 #include <linux/mutex.h>
78 #include <linux/posix-timers.h>
79 #include <linux/syslog.h>
80
81 #include "avc.h"
82 #include "objsec.h"
83 #include "netif.h"
84 #include "netnode.h"
85 #include "netport.h"
86 #include "xfrm.h"
87 #include "netlabel.h"
88 #include "audit.h"
89
90 #define NUM_SEL_MNT_OPTS 5
91
92 extern int selinux_nlmsg_lookup(u16 sclass, u16 nlmsg_type, u32 *perm);
93 extern struct security_operations *security_ops;
94
95 /* SECMARK reference count */
96 atomic_t selinux_secmark_refcount = ATOMIC_INIT(0);
97
98 #ifdef CONFIG_SECURITY_SELINUX_DEVELOP
99 int selinux_enforcing;
100
101 static int __init enforcing_setup(char *str)
102 {
103 unsigned long enforcing;
104 if (!strict_strtoul(str, 0, &enforcing))
105 selinux_enforcing = enforcing ? 1 : 0;
106 return 1;
107 }
108 __setup("enforcing=", enforcing_setup);
109 #endif
110
111 #ifdef CONFIG_SECURITY_SELINUX_BOOTPARAM
112 int selinux_enabled = CONFIG_SECURITY_SELINUX_BOOTPARAM_VALUE;
113
114 static int __init selinux_enabled_setup(char *str)
115 {
116 unsigned long enabled;
117 if (!strict_strtoul(str, 0, &enabled))
118 selinux_enabled = enabled ? 1 : 0;
119 return 1;
120 }
121 __setup("selinux=", selinux_enabled_setup);
122 #else
123 int selinux_enabled = 1;
124 #endif
125
126 static struct kmem_cache *sel_inode_cache;
127
128 /**
129 * selinux_secmark_enabled - Check to see if SECMARK is currently enabled
130 *
131 * Description:
132 * This function checks the SECMARK reference counter to see if any SECMARK
133 * targets are currently configured, if the reference counter is greater than
134 * zero SECMARK is considered to be enabled. Returns true (1) if SECMARK is
135 * enabled, false (0) if SECMARK is disabled.
136 *
137 */
138 static int selinux_secmark_enabled(void)
139 {
140 return (atomic_read(&selinux_secmark_refcount) > 0);
141 }
142
143 /*
144 * initialise the security for the init task
145 */
146 static void cred_init_security(void)
147 {
148 struct cred *cred = (struct cred *) current->real_cred;
149 struct task_security_struct *tsec;
150
151 tsec = kzalloc(sizeof(struct task_security_struct), GFP_KERNEL);
152 if (!tsec)
153 panic("SELinux: Failed to initialize initial task.\n");
154
155 tsec->osid = tsec->sid = SECINITSID_KERNEL;
156 cred->security = tsec;
157 }
158
159 /*
160 * get the security ID of a set of credentials
161 */
162 static inline u32 cred_sid(const struct cred *cred)
163 {
164 const struct task_security_struct *tsec;
165
166 tsec = cred->security;
167 return tsec->sid;
168 }
169
170 /*
171 * get the objective security ID of a task
172 */
173 static inline u32 task_sid(const struct task_struct *task)
174 {
175 u32 sid;
176
177 rcu_read_lock();
178 sid = cred_sid(__task_cred(task));
179 rcu_read_unlock();
180 return sid;
181 }
182
183 /*
184 * get the subjective security ID of the current task
185 */
186 static inline u32 current_sid(void)
187 {
188 const struct task_security_struct *tsec = current_security();
189
190 return tsec->sid;
191 }
192
193 /* Allocate and free functions for each kind of security blob. */
194
195 static int inode_alloc_security(struct inode *inode)
196 {
197 struct inode_security_struct *isec;
198 u32 sid = current_sid();
199
200 isec = kmem_cache_zalloc(sel_inode_cache, GFP_NOFS);
201 if (!isec)
202 return -ENOMEM;
203
204 mutex_init(&isec->lock);
205 INIT_LIST_HEAD(&isec->list);
206 isec->inode = inode;
207 isec->sid = SECINITSID_UNLABELED;
208 isec->sclass = SECCLASS_FILE;
209 isec->task_sid = sid;
210 inode->i_security = isec;
211
212 return 0;
213 }
214
215 static void inode_free_security(struct inode *inode)
216 {
217 struct inode_security_struct *isec = inode->i_security;
218 struct superblock_security_struct *sbsec = inode->i_sb->s_security;
219
220 spin_lock(&sbsec->isec_lock);
221 if (!list_empty(&isec->list))
222 list_del_init(&isec->list);
223 spin_unlock(&sbsec->isec_lock);
224
225 inode->i_security = NULL;
226 kmem_cache_free(sel_inode_cache, isec);
227 }
228
229 static int file_alloc_security(struct file *file)
230 {
231 struct file_security_struct *fsec;
232 u32 sid = current_sid();
233
234 fsec = kzalloc(sizeof(struct file_security_struct), GFP_KERNEL);
235 if (!fsec)
236 return -ENOMEM;
237
238 fsec->sid = sid;
239 fsec->fown_sid = sid;
240 file->f_security = fsec;
241
242 return 0;
243 }
244
245 static void file_free_security(struct file *file)
246 {
247 struct file_security_struct *fsec = file->f_security;
248 file->f_security = NULL;
249 kfree(fsec);
250 }
251
252 static int superblock_alloc_security(struct super_block *sb)
253 {
254 struct superblock_security_struct *sbsec;
255
256 sbsec = kzalloc(sizeof(struct superblock_security_struct), GFP_KERNEL);
257 if (!sbsec)
258 return -ENOMEM;
259
260 mutex_init(&sbsec->lock);
261 INIT_LIST_HEAD(&sbsec->isec_head);
262 spin_lock_init(&sbsec->isec_lock);
263 sbsec->sb = sb;
264 sbsec->sid = SECINITSID_UNLABELED;
265 sbsec->def_sid = SECINITSID_FILE;
266 sbsec->mntpoint_sid = SECINITSID_UNLABELED;
267 sb->s_security = sbsec;
268
269 return 0;
270 }
271
272 static void superblock_free_security(struct super_block *sb)
273 {
274 struct superblock_security_struct *sbsec = sb->s_security;
275 sb->s_security = NULL;
276 kfree(sbsec);
277 }
278
279 /* The security server must be initialized before
280 any labeling or access decisions can be provided. */
281 extern int ss_initialized;
282
283 /* The file system's label must be initialized prior to use. */
284
285 static const char *labeling_behaviors[6] = {
286 "uses xattr",
287 "uses transition SIDs",
288 "uses task SIDs",
289 "uses genfs_contexts",
290 "not configured for labeling",
291 "uses mountpoint labeling",
292 };
293
294 static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dentry);
295
296 static inline int inode_doinit(struct inode *inode)
297 {
298 return inode_doinit_with_dentry(inode, NULL);
299 }
300
301 enum {
302 Opt_error = -1,
303 Opt_context = 1,
304 Opt_fscontext = 2,
305 Opt_defcontext = 3,
306 Opt_rootcontext = 4,
307 Opt_labelsupport = 5,
308 };
309
310 static const match_table_t tokens = {
311 {Opt_context, CONTEXT_STR "%s"},
312 {Opt_fscontext, FSCONTEXT_STR "%s"},
313 {Opt_defcontext, DEFCONTEXT_STR "%s"},
314 {Opt_rootcontext, ROOTCONTEXT_STR "%s"},
315 {Opt_labelsupport, LABELSUPP_STR},
316 {Opt_error, NULL},
317 };
318
319 #define SEL_MOUNT_FAIL_MSG "SELinux: duplicate or incompatible mount options\n"
320
321 static int may_context_mount_sb_relabel(u32 sid,
322 struct superblock_security_struct *sbsec,
323 const struct cred *cred)
324 {
325 const struct task_security_struct *tsec = cred->security;
326 int rc;
327
328 rc = avc_has_perm(tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM,
329 FILESYSTEM__RELABELFROM, NULL);
330 if (rc)
331 return rc;
332
333 rc = avc_has_perm(tsec->sid, sid, SECCLASS_FILESYSTEM,
334 FILESYSTEM__RELABELTO, NULL);
335 return rc;
336 }
337
338 static int may_context_mount_inode_relabel(u32 sid,
339 struct superblock_security_struct *sbsec,
340 const struct cred *cred)
341 {
342 const struct task_security_struct *tsec = cred->security;
343 int rc;
344 rc = avc_has_perm(tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM,
345 FILESYSTEM__RELABELFROM, NULL);
346 if (rc)
347 return rc;
348
349 rc = avc_has_perm(sid, sbsec->sid, SECCLASS_FILESYSTEM,
350 FILESYSTEM__ASSOCIATE, NULL);
351 return rc;
352 }
353
354 static int sb_finish_set_opts(struct super_block *sb)
355 {
356 struct superblock_security_struct *sbsec = sb->s_security;
357 struct dentry *root = sb->s_root;
358 struct inode *root_inode = root->d_inode;
359 int rc = 0;
360
361 if (sbsec->behavior == SECURITY_FS_USE_XATTR) {
362 /* Make sure that the xattr handler exists and that no
363 error other than -ENODATA is returned by getxattr on
364 the root directory. -ENODATA is ok, as this may be
365 the first boot of the SELinux kernel before we have
366 assigned xattr values to the filesystem. */
367 if (!root_inode->i_op->getxattr) {
368 printk(KERN_WARNING "SELinux: (dev %s, type %s) has no "
369 "xattr support\n", sb->s_id, sb->s_type->name);
370 rc = -EOPNOTSUPP;
371 goto out;
372 }
373 rc = root_inode->i_op->getxattr(root, XATTR_NAME_SELINUX, NULL, 0);
374 if (rc < 0 && rc != -ENODATA) {
375 if (rc == -EOPNOTSUPP)
376 printk(KERN_WARNING "SELinux: (dev %s, type "
377 "%s) has no security xattr handler\n",
378 sb->s_id, sb->s_type->name);
379 else
380 printk(KERN_WARNING "SELinux: (dev %s, type "
381 "%s) getxattr errno %d\n", sb->s_id,
382 sb->s_type->name, -rc);
383 goto out;
384 }
385 }
386
387 sbsec->flags |= (SE_SBINITIALIZED | SE_SBLABELSUPP);
388
389 if (sbsec->behavior > ARRAY_SIZE(labeling_behaviors))
390 printk(KERN_ERR "SELinux: initialized (dev %s, type %s), unknown behavior\n",
391 sb->s_id, sb->s_type->name);
392 else
393 printk(KERN_DEBUG "SELinux: initialized (dev %s, type %s), %s\n",
394 sb->s_id, sb->s_type->name,
395 labeling_behaviors[sbsec->behavior-1]);
396
397 if (sbsec->behavior == SECURITY_FS_USE_GENFS ||
398 sbsec->behavior == SECURITY_FS_USE_MNTPOINT ||
399 sbsec->behavior == SECURITY_FS_USE_NONE ||
400 sbsec->behavior > ARRAY_SIZE(labeling_behaviors))
401 sbsec->flags &= ~SE_SBLABELSUPP;
402
403 /* Special handling for sysfs. Is genfs but also has setxattr handler*/
404 if (strncmp(sb->s_type->name, "sysfs", sizeof("sysfs")) == 0)
405 sbsec->flags |= SE_SBLABELSUPP;
406
407 /* Initialize the root inode. */
408 rc = inode_doinit_with_dentry(root_inode, root);
409
410 /* Initialize any other inodes associated with the superblock, e.g.
411 inodes created prior to initial policy load or inodes created
412 during get_sb by a pseudo filesystem that directly
413 populates itself. */
414 spin_lock(&sbsec->isec_lock);
415 next_inode:
416 if (!list_empty(&sbsec->isec_head)) {
417 struct inode_security_struct *isec =
418 list_entry(sbsec->isec_head.next,
419 struct inode_security_struct, list);
420 struct inode *inode = isec->inode;
421 spin_unlock(&sbsec->isec_lock);
422 inode = igrab(inode);
423 if (inode) {
424 if (!IS_PRIVATE(inode))
425 inode_doinit(inode);
426 iput(inode);
427 }
428 spin_lock(&sbsec->isec_lock);
429 list_del_init(&isec->list);
430 goto next_inode;
431 }
432 spin_unlock(&sbsec->isec_lock);
433 out:
434 return rc;
435 }
436
437 /*
438 * This function should allow an FS to ask what it's mount security
439 * options were so it can use those later for submounts, displaying
440 * mount options, or whatever.
441 */
442 static int selinux_get_mnt_opts(const struct super_block *sb,
443 struct security_mnt_opts *opts)
444 {
445 int rc = 0, i;
446 struct superblock_security_struct *sbsec = sb->s_security;
447 char *context = NULL;
448 u32 len;
449 char tmp;
450
451 security_init_mnt_opts(opts);
452
453 if (!(sbsec->flags & SE_SBINITIALIZED))
454 return -EINVAL;
455
456 if (!ss_initialized)
457 return -EINVAL;
458
459 tmp = sbsec->flags & SE_MNTMASK;
460 /* count the number of mount options for this sb */
461 for (i = 0; i < 8; i++) {
462 if (tmp & 0x01)
463 opts->num_mnt_opts++;
464 tmp >>= 1;
465 }
466 /* Check if the Label support flag is set */
467 if (sbsec->flags & SE_SBLABELSUPP)
468 opts->num_mnt_opts++;
469
470 opts->mnt_opts = kcalloc(opts->num_mnt_opts, sizeof(char *), GFP_ATOMIC);
471 if (!opts->mnt_opts) {
472 rc = -ENOMEM;
473 goto out_free;
474 }
475
476 opts->mnt_opts_flags = kcalloc(opts->num_mnt_opts, sizeof(int), GFP_ATOMIC);
477 if (!opts->mnt_opts_flags) {
478 rc = -ENOMEM;
479 goto out_free;
480 }
481
482 i = 0;
483 if (sbsec->flags & FSCONTEXT_MNT) {
484 rc = security_sid_to_context(sbsec->sid, &context, &len);
485 if (rc)
486 goto out_free;
487 opts->mnt_opts[i] = context;
488 opts->mnt_opts_flags[i++] = FSCONTEXT_MNT;
489 }
490 if (sbsec->flags & CONTEXT_MNT) {
491 rc = security_sid_to_context(sbsec->mntpoint_sid, &context, &len);
492 if (rc)
493 goto out_free;
494 opts->mnt_opts[i] = context;
495 opts->mnt_opts_flags[i++] = CONTEXT_MNT;
496 }
497 if (sbsec->flags & DEFCONTEXT_MNT) {
498 rc = security_sid_to_context(sbsec->def_sid, &context, &len);
499 if (rc)
500 goto out_free;
501 opts->mnt_opts[i] = context;
502 opts->mnt_opts_flags[i++] = DEFCONTEXT_MNT;
503 }
504 if (sbsec->flags & ROOTCONTEXT_MNT) {
505 struct inode *root = sbsec->sb->s_root->d_inode;
506 struct inode_security_struct *isec = root->i_security;
507
508 rc = security_sid_to_context(isec->sid, &context, &len);
509 if (rc)
510 goto out_free;
511 opts->mnt_opts[i] = context;
512 opts->mnt_opts_flags[i++] = ROOTCONTEXT_MNT;
513 }
514 if (sbsec->flags & SE_SBLABELSUPP) {
515 opts->mnt_opts[i] = NULL;
516 opts->mnt_opts_flags[i++] = SE_SBLABELSUPP;
517 }
518
519 BUG_ON(i != opts->num_mnt_opts);
520
521 return 0;
522
523 out_free:
524 security_free_mnt_opts(opts);
525 return rc;
526 }
527
528 static int bad_option(struct superblock_security_struct *sbsec, char flag,
529 u32 old_sid, u32 new_sid)
530 {
531 char mnt_flags = sbsec->flags & SE_MNTMASK;
532
533 /* check if the old mount command had the same options */
534 if (sbsec->flags & SE_SBINITIALIZED)
535 if (!(sbsec->flags & flag) ||
536 (old_sid != new_sid))
537 return 1;
538
539 /* check if we were passed the same options twice,
540 * aka someone passed context=a,context=b
541 */
542 if (!(sbsec->flags & SE_SBINITIALIZED))
543 if (mnt_flags & flag)
544 return 1;
545 return 0;
546 }
547
548 /*
549 * Allow filesystems with binary mount data to explicitly set mount point
550 * labeling information.
551 */
552 static int selinux_set_mnt_opts(struct super_block *sb,
553 struct security_mnt_opts *opts)
554 {
555 const struct cred *cred = current_cred();
556 int rc = 0, i;
557 struct superblock_security_struct *sbsec = sb->s_security;
558 const char *name = sb->s_type->name;
559 struct inode *inode = sbsec->sb->s_root->d_inode;
560 struct inode_security_struct *root_isec = inode->i_security;
561 u32 fscontext_sid = 0, context_sid = 0, rootcontext_sid = 0;
562 u32 defcontext_sid = 0;
563 char **mount_options = opts->mnt_opts;
564 int *flags = opts->mnt_opts_flags;
565 int num_opts = opts->num_mnt_opts;
566
567 mutex_lock(&sbsec->lock);
568
569 if (!ss_initialized) {
570 if (!num_opts) {
571 /* Defer initialization until selinux_complete_init,
572 after the initial policy is loaded and the security
573 server is ready to handle calls. */
574 goto out;
575 }
576 rc = -EINVAL;
577 printk(KERN_WARNING "SELinux: Unable to set superblock options "
578 "before the security server is initialized\n");
579 goto out;
580 }
581
582 /*
583 * Binary mount data FS will come through this function twice. Once
584 * from an explicit call and once from the generic calls from the vfs.
585 * Since the generic VFS calls will not contain any security mount data
586 * we need to skip the double mount verification.
587 *
588 * This does open a hole in which we will not notice if the first
589 * mount using this sb set explict options and a second mount using
590 * this sb does not set any security options. (The first options
591 * will be used for both mounts)
592 */
593 if ((sbsec->flags & SE_SBINITIALIZED) && (sb->s_type->fs_flags & FS_BINARY_MOUNTDATA)
594 && (num_opts == 0))
595 goto out;
596
597 /*
598 * parse the mount options, check if they are valid sids.
599 * also check if someone is trying to mount the same sb more
600 * than once with different security options.
601 */
602 for (i = 0; i < num_opts; i++) {
603 u32 sid;
604
605 if (flags[i] == SE_SBLABELSUPP)
606 continue;
607 rc = security_context_to_sid(mount_options[i],
608 strlen(mount_options[i]), &sid);
609 if (rc) {
610 printk(KERN_WARNING "SELinux: security_context_to_sid"
611 "(%s) failed for (dev %s, type %s) errno=%d\n",
612 mount_options[i], sb->s_id, name, rc);
613 goto out;
614 }
615 switch (flags[i]) {
616 case FSCONTEXT_MNT:
617 fscontext_sid = sid;
618
619 if (bad_option(sbsec, FSCONTEXT_MNT, sbsec->sid,
620 fscontext_sid))
621 goto out_double_mount;
622
623 sbsec->flags |= FSCONTEXT_MNT;
624 break;
625 case CONTEXT_MNT:
626 context_sid = sid;
627
628 if (bad_option(sbsec, CONTEXT_MNT, sbsec->mntpoint_sid,
629 context_sid))
630 goto out_double_mount;
631
632 sbsec->flags |= CONTEXT_MNT;
633 break;
634 case ROOTCONTEXT_MNT:
635 rootcontext_sid = sid;
636
637 if (bad_option(sbsec, ROOTCONTEXT_MNT, root_isec->sid,
638 rootcontext_sid))
639 goto out_double_mount;
640
641 sbsec->flags |= ROOTCONTEXT_MNT;
642
643 break;
644 case DEFCONTEXT_MNT:
645 defcontext_sid = sid;
646
647 if (bad_option(sbsec, DEFCONTEXT_MNT, sbsec->def_sid,
648 defcontext_sid))
649 goto out_double_mount;
650
651 sbsec->flags |= DEFCONTEXT_MNT;
652
653 break;
654 default:
655 rc = -EINVAL;
656 goto out;
657 }
658 }
659
660 if (sbsec->flags & SE_SBINITIALIZED) {
661 /* previously mounted with options, but not on this attempt? */
662 if ((sbsec->flags & SE_MNTMASK) && !num_opts)
663 goto out_double_mount;
664 rc = 0;
665 goto out;
666 }
667
668 if (strcmp(sb->s_type->name, "proc") == 0)
669 sbsec->flags |= SE_SBPROC;
670
671 /* Determine the labeling behavior to use for this filesystem type. */
672 rc = security_fs_use((sbsec->flags & SE_SBPROC) ? "proc" : sb->s_type->name, &sbsec->behavior, &sbsec->sid);
673 if (rc) {
674 printk(KERN_WARNING "%s: security_fs_use(%s) returned %d\n",
675 __func__, sb->s_type->name, rc);
676 goto out;
677 }
678
679 /* sets the context of the superblock for the fs being mounted. */
680 if (fscontext_sid) {
681 rc = may_context_mount_sb_relabel(fscontext_sid, sbsec, cred);
682 if (rc)
683 goto out;
684
685 sbsec->sid = fscontext_sid;
686 }
687
688 /*
689 * Switch to using mount point labeling behavior.
690 * sets the label used on all file below the mountpoint, and will set
691 * the superblock context if not already set.
692 */
693 if (context_sid) {
694 if (!fscontext_sid) {
695 rc = may_context_mount_sb_relabel(context_sid, sbsec,
696 cred);
697 if (rc)
698 goto out;
699 sbsec->sid = context_sid;
700 } else {
701 rc = may_context_mount_inode_relabel(context_sid, sbsec,
702 cred);
703 if (rc)
704 goto out;
705 }
706 if (!rootcontext_sid)
707 rootcontext_sid = context_sid;
708
709 sbsec->mntpoint_sid = context_sid;
710 sbsec->behavior = SECURITY_FS_USE_MNTPOINT;
711 }
712
713 if (rootcontext_sid) {
714 rc = may_context_mount_inode_relabel(rootcontext_sid, sbsec,
715 cred);
716 if (rc)
717 goto out;
718
719 root_isec->sid = rootcontext_sid;
720 root_isec->initialized = 1;
721 }
722
723 if (defcontext_sid) {
724 if (sbsec->behavior != SECURITY_FS_USE_XATTR) {
725 rc = -EINVAL;
726 printk(KERN_WARNING "SELinux: defcontext option is "
727 "invalid for this filesystem type\n");
728 goto out;
729 }
730
731 if (defcontext_sid != sbsec->def_sid) {
732 rc = may_context_mount_inode_relabel(defcontext_sid,
733 sbsec, cred);
734 if (rc)
735 goto out;
736 }
737
738 sbsec->def_sid = defcontext_sid;
739 }
740
741 rc = sb_finish_set_opts(sb);
742 out:
743 mutex_unlock(&sbsec->lock);
744 return rc;
745 out_double_mount:
746 rc = -EINVAL;
747 printk(KERN_WARNING "SELinux: mount invalid. Same superblock, different "
748 "security settings for (dev %s, type %s)\n", sb->s_id, name);
749 goto out;
750 }
751
752 static void selinux_sb_clone_mnt_opts(const struct super_block *oldsb,
753 struct super_block *newsb)
754 {
755 const struct superblock_security_struct *oldsbsec = oldsb->s_security;
756 struct superblock_security_struct *newsbsec = newsb->s_security;
757
758 int set_fscontext = (oldsbsec->flags & FSCONTEXT_MNT);
759 int set_context = (oldsbsec->flags & CONTEXT_MNT);
760 int set_rootcontext = (oldsbsec->flags & ROOTCONTEXT_MNT);
761
762 /*
763 * if the parent was able to be mounted it clearly had no special lsm
764 * mount options. thus we can safely deal with this superblock later
765 */
766 if (!ss_initialized)
767 return;
768
769 /* how can we clone if the old one wasn't set up?? */
770 BUG_ON(!(oldsbsec->flags & SE_SBINITIALIZED));
771
772 /* if fs is reusing a sb, just let its options stand... */
773 if (newsbsec->flags & SE_SBINITIALIZED)
774 return;
775
776 mutex_lock(&newsbsec->lock);
777
778 newsbsec->flags = oldsbsec->flags;
779
780 newsbsec->sid = oldsbsec->sid;
781 newsbsec->def_sid = oldsbsec->def_sid;
782 newsbsec->behavior = oldsbsec->behavior;
783
784 if (set_context) {
785 u32 sid = oldsbsec->mntpoint_sid;
786
787 if (!set_fscontext)
788 newsbsec->sid = sid;
789 if (!set_rootcontext) {
790 struct inode *newinode = newsb->s_root->d_inode;
791 struct inode_security_struct *newisec = newinode->i_security;
792 newisec->sid = sid;
793 }
794 newsbsec->mntpoint_sid = sid;
795 }
796 if (set_rootcontext) {
797 const struct inode *oldinode = oldsb->s_root->d_inode;
798 const struct inode_security_struct *oldisec = oldinode->i_security;
799 struct inode *newinode = newsb->s_root->d_inode;
800 struct inode_security_struct *newisec = newinode->i_security;
801
802 newisec->sid = oldisec->sid;
803 }
804
805 sb_finish_set_opts(newsb);
806 mutex_unlock(&newsbsec->lock);
807 }
808
809 static int selinux_parse_opts_str(char *options,
810 struct security_mnt_opts *opts)
811 {
812 char *p;
813 char *context = NULL, *defcontext = NULL;
814 char *fscontext = NULL, *rootcontext = NULL;
815 int rc, num_mnt_opts = 0;
816
817 opts->num_mnt_opts = 0;
818
819 /* Standard string-based options. */
820 while ((p = strsep(&options, "|")) != NULL) {
821 int token;
822 substring_t args[MAX_OPT_ARGS];
823
824 if (!*p)
825 continue;
826
827 token = match_token(p, tokens, args);
828
829 switch (token) {
830 case Opt_context:
831 if (context || defcontext) {
832 rc = -EINVAL;
833 printk(KERN_WARNING SEL_MOUNT_FAIL_MSG);
834 goto out_err;
835 }
836 context = match_strdup(&args[0]);
837 if (!context) {
838 rc = -ENOMEM;
839 goto out_err;
840 }
841 break;
842
843 case Opt_fscontext:
844 if (fscontext) {
845 rc = -EINVAL;
846 printk(KERN_WARNING SEL_MOUNT_FAIL_MSG);
847 goto out_err;
848 }
849 fscontext = match_strdup(&args[0]);
850 if (!fscontext) {
851 rc = -ENOMEM;
852 goto out_err;
853 }
854 break;
855
856 case Opt_rootcontext:
857 if (rootcontext) {
858 rc = -EINVAL;
859 printk(KERN_WARNING SEL_MOUNT_FAIL_MSG);
860 goto out_err;
861 }
862 rootcontext = match_strdup(&args[0]);
863 if (!rootcontext) {
864 rc = -ENOMEM;
865 goto out_err;
866 }
867 break;
868
869 case Opt_defcontext:
870 if (context || defcontext) {
871 rc = -EINVAL;
872 printk(KERN_WARNING SEL_MOUNT_FAIL_MSG);
873 goto out_err;
874 }
875 defcontext = match_strdup(&args[0]);
876 if (!defcontext) {
877 rc = -ENOMEM;
878 goto out_err;
879 }
880 break;
881 case Opt_labelsupport:
882 break;
883 default:
884 rc = -EINVAL;
885 printk(KERN_WARNING "SELinux: unknown mount option\n");
886 goto out_err;
887
888 }
889 }
890
891 rc = -ENOMEM;
892 opts->mnt_opts = kcalloc(NUM_SEL_MNT_OPTS, sizeof(char *), GFP_ATOMIC);
893 if (!opts->mnt_opts)
894 goto out_err;
895
896 opts->mnt_opts_flags = kcalloc(NUM_SEL_MNT_OPTS, sizeof(int), GFP_ATOMIC);
897 if (!opts->mnt_opts_flags) {
898 kfree(opts->mnt_opts);
899 goto out_err;
900 }
901
902 if (fscontext) {
903 opts->mnt_opts[num_mnt_opts] = fscontext;
904 opts->mnt_opts_flags[num_mnt_opts++] = FSCONTEXT_MNT;
905 }
906 if (context) {
907 opts->mnt_opts[num_mnt_opts] = context;
908 opts->mnt_opts_flags[num_mnt_opts++] = CONTEXT_MNT;
909 }
910 if (rootcontext) {
911 opts->mnt_opts[num_mnt_opts] = rootcontext;
912 opts->mnt_opts_flags[num_mnt_opts++] = ROOTCONTEXT_MNT;
913 }
914 if (defcontext) {
915 opts->mnt_opts[num_mnt_opts] = defcontext;
916 opts->mnt_opts_flags[num_mnt_opts++] = DEFCONTEXT_MNT;
917 }
918
919 opts->num_mnt_opts = num_mnt_opts;
920 return 0;
921
922 out_err:
923 kfree(context);
924 kfree(defcontext);
925 kfree(fscontext);
926 kfree(rootcontext);
927 return rc;
928 }
929 /*
930 * string mount options parsing and call set the sbsec
931 */
932 static int superblock_doinit(struct super_block *sb, void *data)
933 {
934 int rc = 0;
935 char *options = data;
936 struct security_mnt_opts opts;
937
938 security_init_mnt_opts(&opts);
939
940 if (!data)
941 goto out;
942
943 BUG_ON(sb->s_type->fs_flags & FS_BINARY_MOUNTDATA);
944
945 rc = selinux_parse_opts_str(options, &opts);
946 if (rc)
947 goto out_err;
948
949 out:
950 rc = selinux_set_mnt_opts(sb, &opts);
951
952 out_err:
953 security_free_mnt_opts(&opts);
954 return rc;
955 }
956
957 static void selinux_write_opts(struct seq_file *m,
958 struct security_mnt_opts *opts)
959 {
960 int i;
961 char *prefix;
962
963 for (i = 0; i < opts->num_mnt_opts; i++) {
964 char *has_comma;
965
966 if (opts->mnt_opts[i])
967 has_comma = strchr(opts->mnt_opts[i], ',');
968 else
969 has_comma = NULL;
970
971 switch (opts->mnt_opts_flags[i]) {
972 case CONTEXT_MNT:
973 prefix = CONTEXT_STR;
974 break;
975 case FSCONTEXT_MNT:
976 prefix = FSCONTEXT_STR;
977 break;
978 case ROOTCONTEXT_MNT:
979 prefix = ROOTCONTEXT_STR;
980 break;
981 case DEFCONTEXT_MNT:
982 prefix = DEFCONTEXT_STR;
983 break;
984 case SE_SBLABELSUPP:
985 seq_putc(m, ',');
986 seq_puts(m, LABELSUPP_STR);
987 continue;
988 default:
989 BUG();
990 };
991 /* we need a comma before each option */
992 seq_putc(m, ',');
993 seq_puts(m, prefix);
994 if (has_comma)
995 seq_putc(m, '\"');
996 seq_puts(m, opts->mnt_opts[i]);
997 if (has_comma)
998 seq_putc(m, '\"');
999 }
1000 }
1001
1002 static int selinux_sb_show_options(struct seq_file *m, struct super_block *sb)
1003 {
1004 struct security_mnt_opts opts;
1005 int rc;
1006
1007 rc = selinux_get_mnt_opts(sb, &opts);
1008 if (rc) {
1009 /* before policy load we may get EINVAL, don't show anything */
1010 if (rc == -EINVAL)
1011 rc = 0;
1012 return rc;
1013 }
1014
1015 selinux_write_opts(m, &opts);
1016
1017 security_free_mnt_opts(&opts);
1018
1019 return rc;
1020 }
1021
1022 static inline u16 inode_mode_to_security_class(umode_t mode)
1023 {
1024 switch (mode & S_IFMT) {
1025 case S_IFSOCK:
1026 return SECCLASS_SOCK_FILE;
1027 case S_IFLNK:
1028 return SECCLASS_LNK_FILE;
1029 case S_IFREG:
1030 return SECCLASS_FILE;
1031 case S_IFBLK:
1032 return SECCLASS_BLK_FILE;
1033 case S_IFDIR:
1034 return SECCLASS_DIR;
1035 case S_IFCHR:
1036 return SECCLASS_CHR_FILE;
1037 case S_IFIFO:
1038 return SECCLASS_FIFO_FILE;
1039
1040 }
1041
1042 return SECCLASS_FILE;
1043 }
1044
1045 static inline int default_protocol_stream(int protocol)
1046 {
1047 return (protocol == IPPROTO_IP || protocol == IPPROTO_TCP);
1048 }
1049
1050 static inline int default_protocol_dgram(int protocol)
1051 {
1052 return (protocol == IPPROTO_IP || protocol == IPPROTO_UDP);
1053 }
1054
1055 static inline u16 socket_type_to_security_class(int family, int type, int protocol)
1056 {
1057 switch (family) {
1058 case PF_UNIX:
1059 switch (type) {
1060 case SOCK_STREAM:
1061 case SOCK_SEQPACKET:
1062 return SECCLASS_UNIX_STREAM_SOCKET;
1063 case SOCK_DGRAM:
1064 return SECCLASS_UNIX_DGRAM_SOCKET;
1065 }
1066 break;
1067 case PF_INET:
1068 case PF_INET6:
1069 switch (type) {
1070 case SOCK_STREAM:
1071 if (default_protocol_stream(protocol))
1072 return SECCLASS_TCP_SOCKET;
1073 else
1074 return SECCLASS_RAWIP_SOCKET;
1075 case SOCK_DGRAM:
1076 if (default_protocol_dgram(protocol))
1077 return SECCLASS_UDP_SOCKET;
1078 else
1079 return SECCLASS_RAWIP_SOCKET;
1080 case SOCK_DCCP:
1081 return SECCLASS_DCCP_SOCKET;
1082 default:
1083 return SECCLASS_RAWIP_SOCKET;
1084 }
1085 break;
1086 case PF_NETLINK:
1087 switch (protocol) {
1088 case NETLINK_ROUTE:
1089 return SECCLASS_NETLINK_ROUTE_SOCKET;
1090 case NETLINK_FIREWALL:
1091 return SECCLASS_NETLINK_FIREWALL_SOCKET;
1092 case NETLINK_INET_DIAG:
1093 return SECCLASS_NETLINK_TCPDIAG_SOCKET;
1094 case NETLINK_NFLOG:
1095 return SECCLASS_NETLINK_NFLOG_SOCKET;
1096 case NETLINK_XFRM:
1097 return SECCLASS_NETLINK_XFRM_SOCKET;
1098 case NETLINK_SELINUX:
1099 return SECCLASS_NETLINK_SELINUX_SOCKET;
1100 case NETLINK_AUDIT:
1101 return SECCLASS_NETLINK_AUDIT_SOCKET;
1102 case NETLINK_IP6_FW:
1103 return SECCLASS_NETLINK_IP6FW_SOCKET;
1104 case NETLINK_DNRTMSG:
1105 return SECCLASS_NETLINK_DNRT_SOCKET;
1106 case NETLINK_KOBJECT_UEVENT:
1107 return SECCLASS_NETLINK_KOBJECT_UEVENT_SOCKET;
1108 default:
1109 return SECCLASS_NETLINK_SOCKET;
1110 }
1111 case PF_PACKET:
1112 return SECCLASS_PACKET_SOCKET;
1113 case PF_KEY:
1114 return SECCLASS_KEY_SOCKET;
1115 case PF_APPLETALK:
1116 return SECCLASS_APPLETALK_SOCKET;
1117 }
1118
1119 return SECCLASS_SOCKET;
1120 }
1121
1122 #ifdef CONFIG_PROC_FS
1123 static int selinux_proc_get_sid(struct proc_dir_entry *de,
1124 u16 tclass,
1125 u32 *sid)
1126 {
1127 int buflen, rc;
1128 char *buffer, *path, *end;
1129
1130 buffer = (char *)__get_free_page(GFP_KERNEL);
1131 if (!buffer)
1132 return -ENOMEM;
1133
1134 buflen = PAGE_SIZE;
1135 end = buffer+buflen;
1136 *--end = '\0';
1137 buflen--;
1138 path = end-1;
1139 *path = '/';
1140 while (de && de != de->parent) {
1141 buflen -= de->namelen + 1;
1142 if (buflen < 0)
1143 break;
1144 end -= de->namelen;
1145 memcpy(end, de->name, de->namelen);
1146 *--end = '/';
1147 path = end;
1148 de = de->parent;
1149 }
1150 rc = security_genfs_sid("proc", path, tclass, sid);
1151 free_page((unsigned long)buffer);
1152 return rc;
1153 }
1154 #else
1155 static int selinux_proc_get_sid(struct proc_dir_entry *de,
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,
1304 sbsec->sid,
1305 isec->sclass,
1306 &sid);
1307 if (rc)
1308 goto out_unlock;
1309 isec->sid = sid;
1310 break;
1311 case SECURITY_FS_USE_MNTPOINT:
1312 isec->sid = sbsec->mntpoint_sid;
1313 break;
1314 default:
1315 /* Default to the fs superblock SID. */
1316 isec->sid = sbsec->sid;
1317
1318 if ((sbsec->flags & SE_SBPROC) && !S_ISLNK(inode->i_mode)) {
1319 struct proc_inode *proci = PROC_I(inode);
1320 if (proci->pde) {
1321 isec->sclass = inode_mode_to_security_class(inode->i_mode);
1322 rc = selinux_proc_get_sid(proci->pde,
1323 isec->sclass,
1324 &sid);
1325 if (rc)
1326 goto out_unlock;
1327 isec->sid = sid;
1328 }
1329 }
1330 break;
1331 }
1332
1333 isec->initialized = 1;
1334
1335 out_unlock:
1336 mutex_unlock(&isec->lock);
1337 out:
1338 if (isec->sclass == SECCLASS_FILE)
1339 isec->sclass = inode_mode_to_security_class(inode->i_mode);
1340 return rc;
1341 }
1342
1343 /* Convert a Linux signal to an access vector. */
1344 static inline u32 signal_to_av(int sig)
1345 {
1346 u32 perm = 0;
1347
1348 switch (sig) {
1349 case SIGCHLD:
1350 /* Commonly granted from child to parent. */
1351 perm = PROCESS__SIGCHLD;
1352 break;
1353 case SIGKILL:
1354 /* Cannot be caught or ignored */
1355 perm = PROCESS__SIGKILL;
1356 break;
1357 case SIGSTOP:
1358 /* Cannot be caught or ignored */
1359 perm = PROCESS__SIGSTOP;
1360 break;
1361 default:
1362 /* All other signals. */
1363 perm = PROCESS__SIGNAL;
1364 break;
1365 }
1366
1367 return perm;
1368 }
1369
1370 /*
1371 * Check permission between a pair of credentials
1372 * fork check, ptrace check, etc.
1373 */
1374 static int cred_has_perm(const struct cred *actor,
1375 const struct cred *target,
1376 u32 perms)
1377 {
1378 u32 asid = cred_sid(actor), tsid = cred_sid(target);
1379
1380 return avc_has_perm(asid, tsid, SECCLASS_PROCESS, perms, NULL);
1381 }
1382
1383 /*
1384 * Check permission between a pair of tasks, e.g. signal checks,
1385 * fork check, ptrace check, etc.
1386 * tsk1 is the actor and tsk2 is the target
1387 * - this uses the default subjective creds of tsk1
1388 */
1389 static int task_has_perm(const struct task_struct *tsk1,
1390 const struct task_struct *tsk2,
1391 u32 perms)
1392 {
1393 const struct task_security_struct *__tsec1, *__tsec2;
1394 u32 sid1, sid2;
1395
1396 rcu_read_lock();
1397 __tsec1 = __task_cred(tsk1)->security; sid1 = __tsec1->sid;
1398 __tsec2 = __task_cred(tsk2)->security; sid2 = __tsec2->sid;
1399 rcu_read_unlock();
1400 return avc_has_perm(sid1, sid2, SECCLASS_PROCESS, perms, NULL);
1401 }
1402
1403 /*
1404 * Check permission between current and another task, e.g. signal checks,
1405 * fork check, ptrace check, etc.
1406 * current is the actor and tsk2 is the target
1407 * - this uses current's subjective creds
1408 */
1409 static int current_has_perm(const struct task_struct *tsk,
1410 u32 perms)
1411 {
1412 u32 sid, tsid;
1413
1414 sid = current_sid();
1415 tsid = task_sid(tsk);
1416 return avc_has_perm(sid, tsid, SECCLASS_PROCESS, perms, NULL);
1417 }
1418
1419 #if CAP_LAST_CAP > 63
1420 #error Fix SELinux to handle capabilities > 63.
1421 #endif
1422
1423 /* Check whether a task is allowed to use a capability. */
1424 static int task_has_capability(struct task_struct *tsk,
1425 const struct cred *cred,
1426 int cap, int audit)
1427 {
1428 struct common_audit_data ad;
1429 struct av_decision avd;
1430 u16 sclass;
1431 u32 sid = cred_sid(cred);
1432 u32 av = CAP_TO_MASK(cap);
1433 int rc;
1434
1435 COMMON_AUDIT_DATA_INIT(&ad, CAP);
1436 ad.tsk = tsk;
1437 ad.u.cap = cap;
1438
1439 switch (CAP_TO_INDEX(cap)) {
1440 case 0:
1441 sclass = SECCLASS_CAPABILITY;
1442 break;
1443 case 1:
1444 sclass = SECCLASS_CAPABILITY2;
1445 break;
1446 default:
1447 printk(KERN_ERR
1448 "SELinux: out of range capability %d\n", cap);
1449 BUG();
1450 }
1451
1452 rc = avc_has_perm_noaudit(sid, sid, sclass, av, 0, &avd);
1453 if (audit == SECURITY_CAP_AUDIT)
1454 avc_audit(sid, sid, sclass, av, &avd, rc, &ad);
1455 return rc;
1456 }
1457
1458 /* Check whether a task is allowed to use a system operation. */
1459 static int task_has_system(struct task_struct *tsk,
1460 u32 perms)
1461 {
1462 u32 sid = task_sid(tsk);
1463
1464 return avc_has_perm(sid, SECINITSID_KERNEL,
1465 SECCLASS_SYSTEM, perms, NULL);
1466 }
1467
1468 /* Check whether a task has a particular permission to an inode.
1469 The 'adp' parameter is optional and allows other audit
1470 data to be passed (e.g. the dentry). */
1471 static int inode_has_perm(const struct cred *cred,
1472 struct inode *inode,
1473 u32 perms,
1474 struct common_audit_data *adp)
1475 {
1476 struct inode_security_struct *isec;
1477 struct common_audit_data ad;
1478 u32 sid;
1479
1480 validate_creds(cred);
1481
1482 if (unlikely(IS_PRIVATE(inode)))
1483 return 0;
1484
1485 sid = cred_sid(cred);
1486 isec = inode->i_security;
1487
1488 if (!adp) {
1489 adp = &ad;
1490 COMMON_AUDIT_DATA_INIT(&ad, FS);
1491 ad.u.fs.inode = inode;
1492 }
1493
1494 return avc_has_perm(sid, isec->sid, isec->sclass, perms, adp);
1495 }
1496
1497 /* Same as inode_has_perm, but pass explicit audit data containing
1498 the dentry to help the auditing code to more easily generate the
1499 pathname if needed. */
1500 static inline int dentry_has_perm(const struct cred *cred,
1501 struct vfsmount *mnt,
1502 struct dentry *dentry,
1503 u32 av)
1504 {
1505 struct inode *inode = dentry->d_inode;
1506 struct common_audit_data ad;
1507
1508 COMMON_AUDIT_DATA_INIT(&ad, FS);
1509 ad.u.fs.path.mnt = mnt;
1510 ad.u.fs.path.dentry = dentry;
1511 return inode_has_perm(cred, inode, av, &ad);
1512 }
1513
1514 /* Check whether a task can use an open file descriptor to
1515 access an inode in a given way. Check access to the
1516 descriptor itself, and then use dentry_has_perm to
1517 check a particular permission to the file.
1518 Access to the descriptor is implicitly granted if it
1519 has the same SID as the process. If av is zero, then
1520 access to the file is not checked, e.g. for cases
1521 where only the descriptor is affected like seek. */
1522 static int file_has_perm(const struct cred *cred,
1523 struct file *file,
1524 u32 av)
1525 {
1526 struct file_security_struct *fsec = file->f_security;
1527 struct inode *inode = file->f_path.dentry->d_inode;
1528 struct common_audit_data ad;
1529 u32 sid = cred_sid(cred);
1530 int rc;
1531
1532 COMMON_AUDIT_DATA_INIT(&ad, FS);
1533 ad.u.fs.path = file->f_path;
1534
1535 if (sid != fsec->sid) {
1536 rc = avc_has_perm(sid, fsec->sid,
1537 SECCLASS_FD,
1538 FD__USE,
1539 &ad);
1540 if (rc)
1541 goto out;
1542 }
1543
1544 /* av is zero if only checking access to the descriptor. */
1545 rc = 0;
1546 if (av)
1547 rc = inode_has_perm(cred, inode, av, &ad);
1548
1549 out:
1550 return rc;
1551 }
1552
1553 /* Check whether a task can create a file. */
1554 static int may_create(struct inode *dir,
1555 struct dentry *dentry,
1556 u16 tclass)
1557 {
1558 const struct task_security_struct *tsec = current_security();
1559 struct inode_security_struct *dsec;
1560 struct superblock_security_struct *sbsec;
1561 u32 sid, newsid;
1562 struct common_audit_data ad;
1563 int rc;
1564
1565 dsec = dir->i_security;
1566 sbsec = dir->i_sb->s_security;
1567
1568 sid = tsec->sid;
1569 newsid = tsec->create_sid;
1570
1571 COMMON_AUDIT_DATA_INIT(&ad, FS);
1572 ad.u.fs.path.dentry = dentry;
1573
1574 rc = avc_has_perm(sid, dsec->sid, SECCLASS_DIR,
1575 DIR__ADD_NAME | DIR__SEARCH,
1576 &ad);
1577 if (rc)
1578 return rc;
1579
1580 if (!newsid || !(sbsec->flags & SE_SBLABELSUPP)) {
1581 rc = security_transition_sid(sid, dsec->sid, tclass, &newsid);
1582 if (rc)
1583 return rc;
1584 }
1585
1586 rc = avc_has_perm(sid, newsid, tclass, FILE__CREATE, &ad);
1587 if (rc)
1588 return rc;
1589
1590 return avc_has_perm(newsid, sbsec->sid,
1591 SECCLASS_FILESYSTEM,
1592 FILESYSTEM__ASSOCIATE, &ad);
1593 }
1594
1595 /* Check whether a task can create a key. */
1596 static int may_create_key(u32 ksid,
1597 struct task_struct *ctx)
1598 {
1599 u32 sid = task_sid(ctx);
1600
1601 return avc_has_perm(sid, ksid, SECCLASS_KEY, KEY__CREATE, NULL);
1602 }
1603
1604 #define MAY_LINK 0
1605 #define MAY_UNLINK 1
1606 #define MAY_RMDIR 2
1607
1608 /* Check whether a task can link, unlink, or rmdir a file/directory. */
1609 static int may_link(struct inode *dir,
1610 struct dentry *dentry,
1611 int kind)
1612
1613 {
1614 struct inode_security_struct *dsec, *isec;
1615 struct common_audit_data ad;
1616 u32 sid = current_sid();
1617 u32 av;
1618 int rc;
1619
1620 dsec = dir->i_security;
1621 isec = dentry->d_inode->i_security;
1622
1623 COMMON_AUDIT_DATA_INIT(&ad, FS);
1624 ad.u.fs.path.dentry = dentry;
1625
1626 av = DIR__SEARCH;
1627 av |= (kind ? DIR__REMOVE_NAME : DIR__ADD_NAME);
1628 rc = avc_has_perm(sid, dsec->sid, SECCLASS_DIR, av, &ad);
1629 if (rc)
1630 return rc;
1631
1632 switch (kind) {
1633 case MAY_LINK:
1634 av = FILE__LINK;
1635 break;
1636 case MAY_UNLINK:
1637 av = FILE__UNLINK;
1638 break;
1639 case MAY_RMDIR:
1640 av = DIR__RMDIR;
1641 break;
1642 default:
1643 printk(KERN_WARNING "SELinux: %s: unrecognized kind %d\n",
1644 __func__, kind);
1645 return 0;
1646 }
1647
1648 rc = avc_has_perm(sid, isec->sid, isec->sclass, av, &ad);
1649 return rc;
1650 }
1651
1652 static inline int may_rename(struct inode *old_dir,
1653 struct dentry *old_dentry,
1654 struct inode *new_dir,
1655 struct dentry *new_dentry)
1656 {
1657 struct inode_security_struct *old_dsec, *new_dsec, *old_isec, *new_isec;
1658 struct common_audit_data ad;
1659 u32 sid = current_sid();
1660 u32 av;
1661 int old_is_dir, new_is_dir;
1662 int rc;
1663
1664 old_dsec = old_dir->i_security;
1665 old_isec = old_dentry->d_inode->i_security;
1666 old_is_dir = S_ISDIR(old_dentry->d_inode->i_mode);
1667 new_dsec = new_dir->i_security;
1668
1669 COMMON_AUDIT_DATA_INIT(&ad, FS);
1670
1671 ad.u.fs.path.dentry = old_dentry;
1672 rc = avc_has_perm(sid, old_dsec->sid, SECCLASS_DIR,
1673 DIR__REMOVE_NAME | DIR__SEARCH, &ad);
1674 if (rc)
1675 return rc;
1676 rc = avc_has_perm(sid, old_isec->sid,
1677 old_isec->sclass, FILE__RENAME, &ad);
1678 if (rc)
1679 return rc;
1680 if (old_is_dir && new_dir != old_dir) {
1681 rc = avc_has_perm(sid, old_isec->sid,
1682 old_isec->sclass, DIR__REPARENT, &ad);
1683 if (rc)
1684 return rc;
1685 }
1686
1687 ad.u.fs.path.dentry = new_dentry;
1688 av = DIR__ADD_NAME | DIR__SEARCH;
1689 if (new_dentry->d_inode)
1690 av |= DIR__REMOVE_NAME;
1691 rc = avc_has_perm(sid, new_dsec->sid, SECCLASS_DIR, av, &ad);
1692 if (rc)
1693 return rc;
1694 if (new_dentry->d_inode) {
1695 new_isec = new_dentry->d_inode->i_security;
1696 new_is_dir = S_ISDIR(new_dentry->d_inode->i_mode);
1697 rc = avc_has_perm(sid, new_isec->sid,
1698 new_isec->sclass,
1699 (new_is_dir ? DIR__RMDIR : FILE__UNLINK), &ad);
1700 if (rc)
1701 return rc;
1702 }
1703
1704 return 0;
1705 }
1706
1707 /* Check whether a task can perform a filesystem operation. */
1708 static int superblock_has_perm(const struct cred *cred,
1709 struct super_block *sb,
1710 u32 perms,
1711 struct common_audit_data *ad)
1712 {
1713 struct superblock_security_struct *sbsec;
1714 u32 sid = cred_sid(cred);
1715
1716 sbsec = sb->s_security;
1717 return avc_has_perm(sid, sbsec->sid, SECCLASS_FILESYSTEM, perms, ad);
1718 }
1719
1720 /* Convert a Linux mode and permission mask to an access vector. */
1721 static inline u32 file_mask_to_av(int mode, int mask)
1722 {
1723 u32 av = 0;
1724
1725 if ((mode & S_IFMT) != S_IFDIR) {
1726 if (mask & MAY_EXEC)
1727 av |= FILE__EXECUTE;
1728 if (mask & MAY_READ)
1729 av |= FILE__READ;
1730
1731 if (mask & MAY_APPEND)
1732 av |= FILE__APPEND;
1733 else if (mask & MAY_WRITE)
1734 av |= FILE__WRITE;
1735
1736 } else {
1737 if (mask & MAY_EXEC)
1738 av |= DIR__SEARCH;
1739 if (mask & MAY_WRITE)
1740 av |= DIR__WRITE;
1741 if (mask & MAY_READ)
1742 av |= DIR__READ;
1743 }
1744
1745 return av;
1746 }
1747
1748 /* Convert a Linux file to an access vector. */
1749 static inline u32 file_to_av(struct file *file)
1750 {
1751 u32 av = 0;
1752
1753 if (file->f_mode & FMODE_READ)
1754 av |= FILE__READ;
1755 if (file->f_mode & FMODE_WRITE) {
1756 if (file->f_flags & O_APPEND)
1757 av |= FILE__APPEND;
1758 else
1759 av |= FILE__WRITE;
1760 }
1761 if (!av) {
1762 /*
1763 * Special file opened with flags 3 for ioctl-only use.
1764 */
1765 av = FILE__IOCTL;
1766 }
1767
1768 return av;
1769 }
1770
1771 /*
1772 * Convert a file to an access vector and include the correct open
1773 * open permission.
1774 */
1775 static inline u32 open_file_to_av(struct file *file)
1776 {
1777 u32 av = file_to_av(file);
1778
1779 if (selinux_policycap_openperm)
1780 av |= FILE__OPEN;
1781
1782 return av;
1783 }
1784
1785 /* Hook functions begin here. */
1786
1787 static int selinux_ptrace_access_check(struct task_struct *child,
1788 unsigned int mode)
1789 {
1790 int rc;
1791
1792 rc = cap_ptrace_access_check(child, mode);
1793 if (rc)
1794 return rc;
1795
1796 if (mode == PTRACE_MODE_READ) {
1797 u32 sid = current_sid();
1798 u32 csid = task_sid(child);
1799 return avc_has_perm(sid, csid, SECCLASS_FILE, FILE__READ, NULL);
1800 }
1801
1802 return current_has_perm(child, PROCESS__PTRACE);
1803 }
1804
1805 static int selinux_ptrace_traceme(struct task_struct *parent)
1806 {
1807 int rc;
1808
1809 rc = cap_ptrace_traceme(parent);
1810 if (rc)
1811 return rc;
1812
1813 return task_has_perm(parent, current, PROCESS__PTRACE);
1814 }
1815
1816 static int selinux_capget(struct task_struct *target, kernel_cap_t *effective,
1817 kernel_cap_t *inheritable, kernel_cap_t *permitted)
1818 {
1819 int error;
1820
1821 error = current_has_perm(target, PROCESS__GETCAP);
1822 if (error)
1823 return error;
1824
1825 return cap_capget(target, effective, inheritable, permitted);
1826 }
1827
1828 static int selinux_capset(struct cred *new, const struct cred *old,
1829 const kernel_cap_t *effective,
1830 const kernel_cap_t *inheritable,
1831 const kernel_cap_t *permitted)
1832 {
1833 int error;
1834
1835 error = cap_capset(new, old,
1836 effective, inheritable, permitted);
1837 if (error)
1838 return error;
1839
1840 return cred_has_perm(old, new, PROCESS__SETCAP);
1841 }
1842
1843 /*
1844 * (This comment used to live with the selinux_task_setuid hook,
1845 * which was removed).
1846 *
1847 * Since setuid only affects the current process, and since the SELinux
1848 * controls are not based on the Linux identity attributes, SELinux does not
1849 * need to control this operation. However, SELinux does control the use of
1850 * the CAP_SETUID and CAP_SETGID capabilities using the capable hook.
1851 */
1852
1853 static int selinux_capable(struct task_struct *tsk, const struct cred *cred,
1854 int cap, int audit)
1855 {
1856 int rc;
1857
1858 rc = cap_capable(tsk, cred, cap, audit);
1859 if (rc)
1860 return rc;
1861
1862 return task_has_capability(tsk, cred, cap, audit);
1863 }
1864
1865 static int selinux_sysctl_get_sid(ctl_table *table, u16 tclass, u32 *sid)
1866 {
1867 int buflen, rc;
1868 char *buffer, *path, *end;
1869
1870 rc = -ENOMEM;
1871 buffer = (char *)__get_free_page(GFP_KERNEL);
1872 if (!buffer)
1873 goto out;
1874
1875 buflen = PAGE_SIZE;
1876 end = buffer+buflen;
1877 *--end = '\0';
1878 buflen--;
1879 path = end-1;
1880 *path = '/';
1881 while (table) {
1882 const char *name = table->procname;
1883 size_t namelen = strlen(name);
1884 buflen -= namelen + 1;
1885 if (buflen < 0)
1886 goto out_free;
1887 end -= namelen;
1888 memcpy(end, name, namelen);
1889 *--end = '/';
1890 path = end;
1891 table = table->parent;
1892 }
1893 buflen -= 4;
1894 if (buflen < 0)
1895 goto out_free;
1896 end -= 4;
1897 memcpy(end, "/sys", 4);
1898 path = end;
1899 rc = security_genfs_sid("proc", path, tclass, sid);
1900 out_free:
1901 free_page((unsigned long)buffer);
1902 out:
1903 return rc;
1904 }
1905
1906 static int selinux_sysctl(ctl_table *table, int op)
1907 {
1908 int error = 0;
1909 u32 av;
1910 u32 tsid, sid;
1911 int rc;
1912
1913 sid = current_sid();
1914
1915 rc = selinux_sysctl_get_sid(table, (op == 0001) ?
1916 SECCLASS_DIR : SECCLASS_FILE, &tsid);
1917 if (rc) {
1918 /* Default to the well-defined sysctl SID. */
1919 tsid = SECINITSID_SYSCTL;
1920 }
1921
1922 /* The op values are "defined" in sysctl.c, thereby creating
1923 * a bad coupling between this module and sysctl.c */
1924 if (op == 001) {
1925 error = avc_has_perm(sid, tsid,
1926 SECCLASS_DIR, DIR__SEARCH, NULL);
1927 } else {
1928 av = 0;
1929 if (op & 004)
1930 av |= FILE__READ;
1931 if (op & 002)
1932 av |= FILE__WRITE;
1933 if (av)
1934 error = avc_has_perm(sid, tsid,
1935 SECCLASS_FILE, av, NULL);
1936 }
1937
1938 return error;
1939 }
1940
1941 static int selinux_quotactl(int cmds, int type, int id, struct super_block *sb)
1942 {
1943 const struct cred *cred = current_cred();
1944 int rc = 0;
1945
1946 if (!sb)
1947 return 0;
1948
1949 switch (cmds) {
1950 case Q_SYNC:
1951 case Q_QUOTAON:
1952 case Q_QUOTAOFF:
1953 case Q_SETINFO:
1954 case Q_SETQUOTA:
1955 rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAMOD, NULL);
1956 break;
1957 case Q_GETFMT:
1958 case Q_GETINFO:
1959 case Q_GETQUOTA:
1960 rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAGET, NULL);
1961 break;
1962 default:
1963 rc = 0; /* let the kernel handle invalid cmds */
1964 break;
1965 }
1966 return rc;
1967 }
1968
1969 static int selinux_quota_on(struct dentry *dentry)
1970 {
1971 const struct cred *cred = current_cred();
1972
1973 return dentry_has_perm(cred, NULL, dentry, FILE__QUOTAON);
1974 }
1975
1976 static int selinux_syslog(int type, bool from_file)
1977 {
1978 int rc;
1979
1980 rc = cap_syslog(type, from_file);
1981 if (rc)
1982 return rc;
1983
1984 switch (type) {
1985 case SYSLOG_ACTION_READ_ALL: /* Read last kernel messages */
1986 case SYSLOG_ACTION_SIZE_BUFFER: /* Return size of the log buffer */
1987 rc = task_has_system(current, SYSTEM__SYSLOG_READ);
1988 break;
1989 case SYSLOG_ACTION_CONSOLE_OFF: /* Disable logging to console */
1990 case SYSLOG_ACTION_CONSOLE_ON: /* Enable logging to console */
1991 /* Set level of messages printed to console */
1992 case SYSLOG_ACTION_CONSOLE_LEVEL:
1993 rc = task_has_system(current, SYSTEM__SYSLOG_CONSOLE);
1994 break;
1995 case SYSLOG_ACTION_CLOSE: /* Close log */
1996 case SYSLOG_ACTION_OPEN: /* Open log */
1997 case SYSLOG_ACTION_READ: /* Read from log */
1998 case SYSLOG_ACTION_READ_CLEAR: /* Read/clear last kernel messages */
1999 case SYSLOG_ACTION_CLEAR: /* Clear ring buffer */
2000 default:
2001 rc = task_has_system(current, SYSTEM__SYSLOG_MOD);
2002 break;
2003 }
2004 return rc;
2005 }
2006
2007 /*
2008 * Check that a process has enough memory to allocate a new virtual
2009 * mapping. 0 means there is enough memory for the allocation to
2010 * succeed and -ENOMEM implies there is not.
2011 *
2012 * Do not audit the selinux permission check, as this is applied to all
2013 * processes that allocate mappings.
2014 */
2015 static int selinux_vm_enough_memory(struct mm_struct *mm, long pages)
2016 {
2017 int rc, cap_sys_admin = 0;
2018
2019 rc = selinux_capable(current, current_cred(), CAP_SYS_ADMIN,
2020 SECURITY_CAP_NOAUDIT);
2021 if (rc == 0)
2022 cap_sys_admin = 1;
2023
2024 return __vm_enough_memory(mm, pages, cap_sys_admin);
2025 }
2026
2027 /* binprm security operations */
2028
2029 static int selinux_bprm_set_creds(struct linux_binprm *bprm)
2030 {
2031 const struct task_security_struct *old_tsec;
2032 struct task_security_struct *new_tsec;
2033 struct inode_security_struct *isec;
2034 struct common_audit_data ad;
2035 struct inode *inode = bprm->file->f_path.dentry->d_inode;
2036 int rc;
2037
2038 rc = cap_bprm_set_creds(bprm);
2039 if (rc)
2040 return rc;
2041
2042 /* SELinux context only depends on initial program or script and not
2043 * the script interpreter */
2044 if (bprm->cred_prepared)
2045 return 0;
2046
2047 old_tsec = current_security();
2048 new_tsec = bprm->cred->security;
2049 isec = inode->i_security;
2050
2051 /* Default to the current task SID. */
2052 new_tsec->sid = old_tsec->sid;
2053 new_tsec->osid = old_tsec->sid;
2054
2055 /* Reset fs, key, and sock SIDs on execve. */
2056 new_tsec->create_sid = 0;
2057 new_tsec->keycreate_sid = 0;
2058 new_tsec->sockcreate_sid = 0;
2059
2060 if (old_tsec->exec_sid) {
2061 new_tsec->sid = old_tsec->exec_sid;
2062 /* Reset exec SID on execve. */
2063 new_tsec->exec_sid = 0;
2064 } else {
2065 /* Check for a default transition on this program. */
2066 rc = security_transition_sid(old_tsec->sid, isec->sid,
2067 SECCLASS_PROCESS, &new_tsec->sid);
2068 if (rc)
2069 return rc;
2070 }
2071
2072 COMMON_AUDIT_DATA_INIT(&ad, FS);
2073 ad.u.fs.path = bprm->file->f_path;
2074
2075 if (bprm->file->f_path.mnt->mnt_flags & MNT_NOSUID)
2076 new_tsec->sid = old_tsec->sid;
2077
2078 if (new_tsec->sid == old_tsec->sid) {
2079 rc = avc_has_perm(old_tsec->sid, isec->sid,
2080 SECCLASS_FILE, FILE__EXECUTE_NO_TRANS, &ad);
2081 if (rc)
2082 return rc;
2083 } else {
2084 /* Check permissions for the transition. */
2085 rc = avc_has_perm(old_tsec->sid, new_tsec->sid,
2086 SECCLASS_PROCESS, PROCESS__TRANSITION, &ad);
2087 if (rc)
2088 return rc;
2089
2090 rc = avc_has_perm(new_tsec->sid, isec->sid,
2091 SECCLASS_FILE, FILE__ENTRYPOINT, &ad);
2092 if (rc)
2093 return rc;
2094
2095 /* Check for shared state */
2096 if (bprm->unsafe & LSM_UNSAFE_SHARE) {
2097 rc = avc_has_perm(old_tsec->sid, new_tsec->sid,
2098 SECCLASS_PROCESS, PROCESS__SHARE,
2099 NULL);
2100 if (rc)
2101 return -EPERM;
2102 }
2103
2104 /* Make sure that anyone attempting to ptrace over a task that
2105 * changes its SID has the appropriate permit */
2106 if (bprm->unsafe &
2107 (LSM_UNSAFE_PTRACE | LSM_UNSAFE_PTRACE_CAP)) {
2108 struct task_struct *tracer;
2109 struct task_security_struct *sec;
2110 u32 ptsid = 0;
2111
2112 rcu_read_lock();
2113 tracer = tracehook_tracer_task(current);
2114 if (likely(tracer != NULL)) {
2115 sec = __task_cred(tracer)->security;
2116 ptsid = sec->sid;
2117 }
2118 rcu_read_unlock();
2119
2120 if (ptsid != 0) {
2121 rc = avc_has_perm(ptsid, new_tsec->sid,
2122 SECCLASS_PROCESS,
2123 PROCESS__PTRACE, NULL);
2124 if (rc)
2125 return -EPERM;
2126 }
2127 }
2128
2129 /* Clear any possibly unsafe personality bits on exec: */
2130 bprm->per_clear |= PER_CLEAR_ON_SETID;
2131 }
2132
2133 return 0;
2134 }
2135
2136 static int selinux_bprm_secureexec(struct linux_binprm *bprm)
2137 {
2138 const struct task_security_struct *tsec = current_security();
2139 u32 sid, osid;
2140 int atsecure = 0;
2141
2142 sid = tsec->sid;
2143 osid = tsec->osid;
2144
2145 if (osid != sid) {
2146 /* Enable secure mode for SIDs transitions unless
2147 the noatsecure permission is granted between
2148 the two SIDs, i.e. ahp returns 0. */
2149 atsecure = avc_has_perm(osid, sid,
2150 SECCLASS_PROCESS,
2151 PROCESS__NOATSECURE, NULL);
2152 }
2153
2154 return (atsecure || cap_bprm_secureexec(bprm));
2155 }
2156
2157 extern struct vfsmount *selinuxfs_mount;
2158 extern struct dentry *selinux_null;
2159
2160 /* Derived from fs/exec.c:flush_old_files. */
2161 static inline void flush_unauthorized_files(const struct cred *cred,
2162 struct files_struct *files)
2163 {
2164 struct common_audit_data ad;
2165 struct file *file, *devnull = NULL;
2166 struct tty_struct *tty;
2167 struct fdtable *fdt;
2168 long j = -1;
2169 int drop_tty = 0;
2170
2171 tty = get_current_tty();
2172 if (tty) {
2173 spin_lock(&tty_files_lock);
2174 if (!list_empty(&tty->tty_files)) {
2175 struct inode *inode;
2176
2177 /* Revalidate access to controlling tty.
2178 Use inode_has_perm on the tty inode directly rather
2179 than using file_has_perm, as this particular open
2180 file may belong to another process and we are only
2181 interested in the inode-based check here. */
2182 file = list_first_entry(&tty->tty_files, struct file, f_u.fu_list);
2183 inode = file->f_path.dentry->d_inode;
2184 if (inode_has_perm(cred, inode,
2185 FILE__READ | FILE__WRITE, NULL)) {
2186 drop_tty = 1;
2187 }
2188 }
2189 spin_unlock(&tty_files_lock);
2190 tty_kref_put(tty);
2191 }
2192 /* Reset controlling tty. */
2193 if (drop_tty)
2194 no_tty();
2195
2196 /* Revalidate access to inherited open files. */
2197
2198 COMMON_AUDIT_DATA_INIT(&ad, FS);
2199
2200 spin_lock(&files->file_lock);
2201 for (;;) {
2202 unsigned long set, i;
2203 int fd;
2204
2205 j++;
2206 i = j * __NFDBITS;
2207 fdt = files_fdtable(files);
2208 if (i >= fdt->max_fds)
2209 break;
2210 set = fdt->open_fds->fds_bits[j];
2211 if (!set)
2212 continue;
2213 spin_unlock(&files->file_lock);
2214 for ( ; set ; i++, set >>= 1) {
2215 if (set & 1) {
2216 file = fget(i);
2217 if (!file)
2218 continue;
2219 if (file_has_perm(cred,
2220 file,
2221 file_to_av(file))) {
2222 sys_close(i);
2223 fd = get_unused_fd();
2224 if (fd != i) {
2225 if (fd >= 0)
2226 put_unused_fd(fd);
2227 fput(file);
2228 continue;
2229 }
2230 if (devnull) {
2231 get_file(devnull);
2232 } else {
2233 devnull = dentry_open(
2234 dget(selinux_null),
2235 mntget(selinuxfs_mount),
2236 O_RDWR, cred);
2237 if (IS_ERR(devnull)) {
2238 devnull = NULL;
2239 put_unused_fd(fd);
2240 fput(file);
2241 continue;
2242 }
2243 }
2244 fd_install(fd, devnull);
2245 }
2246 fput(file);
2247 }
2248 }
2249 spin_lock(&files->file_lock);
2250
2251 }
2252 spin_unlock(&files->file_lock);
2253 }
2254
2255 /*
2256 * Prepare a process for imminent new credential changes due to exec
2257 */
2258 static void selinux_bprm_committing_creds(struct linux_binprm *bprm)
2259 {
2260 struct task_security_struct *new_tsec;
2261 struct rlimit *rlim, *initrlim;
2262 int rc, i;
2263
2264 new_tsec = bprm->cred->security;
2265 if (new_tsec->sid == new_tsec->osid)
2266 return;
2267
2268 /* Close files for which the new task SID is not authorized. */
2269 flush_unauthorized_files(bprm->cred, current->files);
2270
2271 /* Always clear parent death signal on SID transitions. */
2272 current->pdeath_signal = 0;
2273
2274 /* Check whether the new SID can inherit resource limits from the old
2275 * SID. If not, reset all soft limits to the lower of the current
2276 * task's hard limit and the init task's soft limit.
2277 *
2278 * Note that the setting of hard limits (even to lower them) can be
2279 * controlled by the setrlimit check. The inclusion of the init task's
2280 * soft limit into the computation is to avoid resetting soft limits
2281 * higher than the default soft limit for cases where the default is
2282 * lower than the hard limit, e.g. RLIMIT_CORE or RLIMIT_STACK.
2283 */
2284 rc = avc_has_perm(new_tsec->osid, new_tsec->sid, SECCLASS_PROCESS,
2285 PROCESS__RLIMITINH, NULL);
2286 if (rc) {
2287 /* protect against do_prlimit() */
2288 task_lock(current);
2289 for (i = 0; i < RLIM_NLIMITS; i++) {
2290 rlim = current->signal->rlim + i;
2291 initrlim = init_task.signal->rlim + i;
2292 rlim->rlim_cur = min(rlim->rlim_max, initrlim->rlim_cur);
2293 }
2294 task_unlock(current);
2295 update_rlimit_cpu(current, rlimit(RLIMIT_CPU));
2296 }
2297 }
2298
2299 /*
2300 * Clean up the process immediately after the installation of new credentials
2301 * due to exec
2302 */
2303 static void selinux_bprm_committed_creds(struct linux_binprm *bprm)
2304 {
2305 const struct task_security_struct *tsec = current_security();
2306 struct itimerval itimer;
2307 u32 osid, sid;
2308 int rc, i;
2309
2310 osid = tsec->osid;
2311 sid = tsec->sid;
2312
2313 if (sid == osid)
2314 return;
2315
2316 /* Check whether the new SID can inherit signal state from the old SID.
2317 * If not, clear itimers to avoid subsequent signal generation and
2318 * flush and unblock signals.
2319 *
2320 * This must occur _after_ the task SID has been updated so that any
2321 * kill done after the flush will be checked against the new SID.
2322 */
2323 rc = avc_has_perm(osid, sid, SECCLASS_PROCESS, PROCESS__SIGINH, NULL);
2324 if (rc) {
2325 memset(&itimer, 0, sizeof itimer);
2326 for (i = 0; i < 3; i++)
2327 do_setitimer(i, &itimer, NULL);
2328 spin_lock_irq(&current->sighand->siglock);
2329 if (!(current->signal->flags & SIGNAL_GROUP_EXIT)) {
2330 __flush_signals(current);
2331 flush_signal_handlers(current, 1);
2332 sigemptyset(&current->blocked);
2333 }
2334 spin_unlock_irq(&current->sighand->siglock);
2335 }
2336
2337 /* Wake up the parent if it is waiting so that it can recheck
2338 * wait permission to the new task SID. */
2339 read_lock(&tasklist_lock);
2340 __wake_up_parent(current, current->real_parent);
2341 read_unlock(&tasklist_lock);
2342 }
2343
2344 /* superblock security operations */
2345
2346 static int selinux_sb_alloc_security(struct super_block *sb)
2347 {
2348 return superblock_alloc_security(sb);
2349 }
2350
2351 static void selinux_sb_free_security(struct super_block *sb)
2352 {
2353 superblock_free_security(sb);
2354 }
2355
2356 static inline int match_prefix(char *prefix, int plen, char *option, int olen)
2357 {
2358 if (plen > olen)
2359 return 0;
2360
2361 return !memcmp(prefix, option, plen);
2362 }
2363
2364 static inline int selinux_option(char *option, int len)
2365 {
2366 return (match_prefix(CONTEXT_STR, sizeof(CONTEXT_STR)-1, option, len) ||
2367 match_prefix(FSCONTEXT_STR, sizeof(FSCONTEXT_STR)-1, option, len) ||
2368 match_prefix(DEFCONTEXT_STR, sizeof(DEFCONTEXT_STR)-1, option, len) ||
2369 match_prefix(ROOTCONTEXT_STR, sizeof(ROOTCONTEXT_STR)-1, option, len) ||
2370 match_prefix(LABELSUPP_STR, sizeof(LABELSUPP_STR)-1, option, len));
2371 }
2372
2373 static inline void take_option(char **to, char *from, int *first, int len)
2374 {
2375 if (!*first) {
2376 **to = ',';
2377 *to += 1;
2378 } else
2379 *first = 0;
2380 memcpy(*to, from, len);
2381 *to += len;
2382 }
2383
2384 static inline void take_selinux_option(char **to, char *from, int *first,
2385 int len)
2386 {
2387 int current_size = 0;
2388
2389 if (!*first) {
2390 **to = '|';
2391 *to += 1;
2392 } else
2393 *first = 0;
2394
2395 while (current_size < len) {
2396 if (*from != '"') {
2397 **to = *from;
2398 *to += 1;
2399 }
2400 from += 1;
2401 current_size += 1;
2402 }
2403 }
2404
2405 static int selinux_sb_copy_data(char *orig, char *copy)
2406 {
2407 int fnosec, fsec, rc = 0;
2408 char *in_save, *in_curr, *in_end;
2409 char *sec_curr, *nosec_save, *nosec;
2410 int open_quote = 0;
2411
2412 in_curr = orig;
2413 sec_curr = copy;
2414
2415 nosec = (char *)get_zeroed_page(GFP_KERNEL);
2416 if (!nosec) {
2417 rc = -ENOMEM;
2418 goto out;
2419 }
2420
2421 nosec_save = nosec;
2422 fnosec = fsec = 1;
2423 in_save = in_end = orig;
2424
2425 do {
2426 if (*in_end == '"')
2427 open_quote = !open_quote;
2428 if ((*in_end == ',' && open_quote == 0) ||
2429 *in_end == '\0') {
2430 int len = in_end - in_curr;
2431
2432 if (selinux_option(in_curr, len))
2433 take_selinux_option(&sec_curr, in_curr, &fsec, len);
2434 else
2435 take_option(&nosec, in_curr, &fnosec, len);
2436
2437 in_curr = in_end + 1;
2438 }
2439 } while (*in_end++);
2440
2441 strcpy(in_save, nosec_save);
2442 free_page((unsigned long)nosec_save);
2443 out:
2444 return rc;
2445 }
2446
2447 static int selinux_sb_kern_mount(struct super_block *sb, int flags, void *data)
2448 {
2449 const struct cred *cred = current_cred();
2450 struct common_audit_data ad;
2451 int rc;
2452
2453 rc = superblock_doinit(sb, data);
2454 if (rc)
2455 return rc;
2456
2457 /* Allow all mounts performed by the kernel */
2458 if (flags & MS_KERNMOUNT)
2459 return 0;
2460
2461 COMMON_AUDIT_DATA_INIT(&ad, FS);
2462 ad.u.fs.path.dentry = sb->s_root;
2463 return superblock_has_perm(cred, sb, FILESYSTEM__MOUNT, &ad);
2464 }
2465
2466 static int selinux_sb_statfs(struct dentry *dentry)
2467 {
2468 const struct cred *cred = current_cred();
2469 struct common_audit_data ad;
2470
2471 COMMON_AUDIT_DATA_INIT(&ad, FS);
2472 ad.u.fs.path.dentry = dentry->d_sb->s_root;
2473 return superblock_has_perm(cred, dentry->d_sb, FILESYSTEM__GETATTR, &ad);
2474 }
2475
2476 static int selinux_mount(char *dev_name,
2477 struct path *path,
2478 char *type,
2479 unsigned long flags,
2480 void *data)
2481 {
2482 const struct cred *cred = current_cred();
2483
2484 if (flags & MS_REMOUNT)
2485 return superblock_has_perm(cred, path->mnt->mnt_sb,
2486 FILESYSTEM__REMOUNT, NULL);
2487 else
2488 return dentry_has_perm(cred, path->mnt, path->dentry,
2489 FILE__MOUNTON);
2490 }
2491
2492 static int selinux_umount(struct vfsmount *mnt, int flags)
2493 {
2494 const struct cred *cred = current_cred();
2495
2496 return superblock_has_perm(cred, mnt->mnt_sb,
2497 FILESYSTEM__UNMOUNT, NULL);
2498 }
2499
2500 /* inode security operations */
2501
2502 static int selinux_inode_alloc_security(struct inode *inode)
2503 {
2504 return inode_alloc_security(inode);
2505 }
2506
2507 static void selinux_inode_free_security(struct inode *inode)
2508 {
2509 inode_free_security(inode);
2510 }
2511
2512 static int selinux_inode_init_security(struct inode *inode, struct inode *dir,
2513 char **name, void **value,
2514 size_t *len)
2515 {
2516 const struct task_security_struct *tsec = current_security();
2517 struct inode_security_struct *dsec;
2518 struct superblock_security_struct *sbsec;
2519 u32 sid, newsid, clen;
2520 int rc;
2521 char *namep = NULL, *context;
2522
2523 dsec = dir->i_security;
2524 sbsec = dir->i_sb->s_security;
2525
2526 sid = tsec->sid;
2527 newsid = tsec->create_sid;
2528
2529 if (!newsid || !(sbsec->flags & SE_SBLABELSUPP)) {
2530 rc = security_transition_sid(sid, dsec->sid,
2531 inode_mode_to_security_class(inode->i_mode),
2532 &newsid);
2533 if (rc) {
2534 printk(KERN_WARNING "%s: "
2535 "security_transition_sid failed, rc=%d (dev=%s "
2536 "ino=%ld)\n",
2537 __func__,
2538 -rc, inode->i_sb->s_id, inode->i_ino);
2539 return rc;
2540 }
2541 }
2542
2543 /* Possibly defer initialization to selinux_complete_init. */
2544 if (sbsec->flags & SE_SBINITIALIZED) {
2545 struct inode_security_struct *isec = inode->i_security;
2546 isec->sclass = inode_mode_to_security_class(inode->i_mode);
2547 isec->sid = newsid;
2548 isec->initialized = 1;
2549 }
2550
2551 if (!ss_initialized || !(sbsec->flags & SE_SBLABELSUPP))
2552 return -EOPNOTSUPP;
2553
2554 if (name) {
2555 namep = kstrdup(XATTR_SELINUX_SUFFIX, GFP_NOFS);
2556 if (!namep)
2557 return -ENOMEM;
2558 *name = namep;
2559 }
2560
2561 if (value && len) {
2562 rc = security_sid_to_context_force(newsid, &context, &clen);
2563 if (rc) {
2564 kfree(namep);
2565 return rc;
2566 }
2567 *value = context;
2568 *len = clen;
2569 }
2570
2571 return 0;
2572 }
2573
2574 static int selinux_inode_create(struct inode *dir, struct dentry *dentry, int mask)
2575 {
2576 return may_create(dir, dentry, SECCLASS_FILE);
2577 }
2578
2579 static int selinux_inode_link(struct dentry *old_dentry, struct inode *dir, struct dentry *new_dentry)
2580 {
2581 return may_link(dir, old_dentry, MAY_LINK);
2582 }
2583
2584 static int selinux_inode_unlink(struct inode *dir, struct dentry *dentry)
2585 {
2586 return may_link(dir, dentry, MAY_UNLINK);
2587 }
2588
2589 static int selinux_inode_symlink(struct inode *dir, struct dentry *dentry, const char *name)
2590 {
2591 return may_create(dir, dentry, SECCLASS_LNK_FILE);
2592 }
2593
2594 static int selinux_inode_mkdir(struct inode *dir, struct dentry *dentry, int mask)
2595 {
2596 return may_create(dir, dentry, SECCLASS_DIR);
2597 }
2598
2599 static int selinux_inode_rmdir(struct inode *dir, struct dentry *dentry)
2600 {
2601 return may_link(dir, dentry, MAY_RMDIR);
2602 }
2603
2604 static int selinux_inode_mknod(struct inode *dir, struct dentry *dentry, int mode, dev_t dev)
2605 {
2606 return may_create(dir, dentry, inode_mode_to_security_class(mode));
2607 }
2608
2609 static int selinux_inode_rename(struct inode *old_inode, struct dentry *old_dentry,
2610 struct inode *new_inode, struct dentry *new_dentry)
2611 {
2612 return may_rename(old_inode, old_dentry, new_inode, new_dentry);
2613 }
2614
2615 static int selinux_inode_readlink(struct dentry *dentry)
2616 {
2617 const struct cred *cred = current_cred();
2618
2619 return dentry_has_perm(cred, NULL, dentry, FILE__READ);
2620 }
2621
2622 static int selinux_inode_follow_link(struct dentry *dentry, struct nameidata *nameidata)
2623 {
2624 const struct cred *cred = current_cred();
2625
2626 return dentry_has_perm(cred, NULL, dentry, FILE__READ);
2627 }
2628
2629 static int selinux_inode_permission(struct inode *inode, int mask)
2630 {
2631 const struct cred *cred = current_cred();
2632 struct common_audit_data ad;
2633 u32 perms;
2634 bool from_access;
2635
2636 from_access = mask & MAY_ACCESS;
2637 mask &= (MAY_READ|MAY_WRITE|MAY_EXEC|MAY_APPEND);
2638
2639 /* No permission to check. Existence test. */
2640 if (!mask)
2641 return 0;
2642
2643 COMMON_AUDIT_DATA_INIT(&ad, FS);
2644 ad.u.fs.inode = inode;
2645
2646 if (from_access)
2647 ad.selinux_audit_data.auditdeny |= FILE__AUDIT_ACCESS;
2648
2649 perms = file_mask_to_av(inode->i_mode, mask);
2650
2651 return inode_has_perm(cred, inode, perms, &ad);
2652 }
2653
2654 static int selinux_inode_setattr(struct dentry *dentry, struct iattr *iattr)
2655 {
2656 const struct cred *cred = current_cred();
2657 unsigned int ia_valid = iattr->ia_valid;
2658
2659 /* ATTR_FORCE is just used for ATTR_KILL_S[UG]ID. */
2660 if (ia_valid & ATTR_FORCE) {
2661 ia_valid &= ~(ATTR_KILL_SUID | ATTR_KILL_SGID | ATTR_MODE |
2662 ATTR_FORCE);
2663 if (!ia_valid)
2664 return 0;
2665 }
2666
2667 if (ia_valid & (ATTR_MODE | ATTR_UID | ATTR_GID |
2668 ATTR_ATIME_SET | ATTR_MTIME_SET | ATTR_TIMES_SET))
2669 return dentry_has_perm(cred, NULL, dentry, FILE__SETATTR);
2670
2671 return dentry_has_perm(cred, NULL, dentry, FILE__WRITE);
2672 }
2673
2674 static int selinux_inode_getattr(struct vfsmount *mnt, struct dentry *dentry)
2675 {
2676 const struct cred *cred = current_cred();
2677
2678 return dentry_has_perm(cred, mnt, dentry, FILE__GETATTR);
2679 }
2680
2681 static int selinux_inode_setotherxattr(struct dentry *dentry, const char *name)
2682 {
2683 const struct cred *cred = current_cred();
2684
2685 if (!strncmp(name, XATTR_SECURITY_PREFIX,
2686 sizeof XATTR_SECURITY_PREFIX - 1)) {
2687 if (!strcmp(name, XATTR_NAME_CAPS)) {
2688 if (!capable(CAP_SETFCAP))
2689 return -EPERM;
2690 } else if (!capable(CAP_SYS_ADMIN)) {
2691 /* A different attribute in the security namespace.
2692 Restrict to administrator. */
2693 return -EPERM;
2694 }
2695 }
2696
2697 /* Not an attribute we recognize, so just check the
2698 ordinary setattr permission. */
2699 return dentry_has_perm(cred, NULL, dentry, FILE__SETATTR);
2700 }
2701
2702 static int selinux_inode_setxattr(struct dentry *dentry, const char *name,
2703 const void *value, size_t size, int flags)
2704 {
2705 struct inode *inode = dentry->d_inode;
2706 struct inode_security_struct *isec = inode->i_security;
2707 struct superblock_security_struct *sbsec;
2708 struct common_audit_data ad;
2709 u32 newsid, sid = current_sid();
2710 int rc = 0;
2711
2712 if (strcmp(name, XATTR_NAME_SELINUX))
2713 return selinux_inode_setotherxattr(dentry, name);
2714
2715 sbsec = inode->i_sb->s_security;
2716 if (!(sbsec->flags & SE_SBLABELSUPP))
2717 return -EOPNOTSUPP;
2718
2719 if (!is_owner_or_cap(inode))
2720 return -EPERM;
2721
2722 COMMON_AUDIT_DATA_INIT(&ad, FS);
2723 ad.u.fs.path.dentry = dentry;
2724
2725 rc = avc_has_perm(sid, isec->sid, isec->sclass,
2726 FILE__RELABELFROM, &ad);
2727 if (rc)
2728 return rc;
2729
2730 rc = security_context_to_sid(value, size, &newsid);
2731 if (rc == -EINVAL) {
2732 if (!capable(CAP_MAC_ADMIN))
2733 return rc;
2734 rc = security_context_to_sid_force(value, size, &newsid);
2735 }
2736 if (rc)
2737 return rc;
2738
2739 rc = avc_has_perm(sid, newsid, isec->sclass,
2740 FILE__RELABELTO, &ad);
2741 if (rc)
2742 return rc;
2743
2744 rc = security_validate_transition(isec->sid, newsid, sid,
2745 isec->sclass);
2746 if (rc)
2747 return rc;
2748
2749 return avc_has_perm(newsid,
2750 sbsec->sid,
2751 SECCLASS_FILESYSTEM,
2752 FILESYSTEM__ASSOCIATE,
2753 &ad);
2754 }
2755
2756 static void selinux_inode_post_setxattr(struct dentry *dentry, const char *name,
2757 const void *value, size_t size,
2758 int flags)
2759 {
2760 struct inode *inode = dentry->d_inode;
2761 struct inode_security_struct *isec = inode->i_security;
2762 u32 newsid;
2763 int rc;
2764
2765 if (strcmp(name, XATTR_NAME_SELINUX)) {
2766 /* Not an attribute we recognize, so nothing to do. */
2767 return;
2768 }
2769
2770 rc = security_context_to_sid_force(value, size, &newsid);
2771 if (rc) {
2772 printk(KERN_ERR "SELinux: unable to map context to SID"
2773 "for (%s, %lu), rc=%d\n",
2774 inode->i_sb->s_id, inode->i_ino, -rc);
2775 return;
2776 }
2777
2778 isec->sid = newsid;
2779 return;
2780 }
2781
2782 static int selinux_inode_getxattr(struct dentry *dentry, const char *name)
2783 {
2784 const struct cred *cred = current_cred();
2785
2786 return dentry_has_perm(cred, NULL, dentry, FILE__GETATTR);
2787 }
2788
2789 static int selinux_inode_listxattr(struct dentry *dentry)
2790 {
2791 const struct cred *cred = current_cred();
2792
2793 return dentry_has_perm(cred, NULL, dentry, FILE__GETATTR);
2794 }
2795
2796 static int selinux_inode_removexattr(struct dentry *dentry, const char *name)
2797 {
2798 if (strcmp(name, XATTR_NAME_SELINUX))
2799 return selinux_inode_setotherxattr(dentry, name);
2800
2801 /* No one is allowed to remove a SELinux security label.
2802 You can change the label, but all data must be labeled. */
2803 return -EACCES;
2804 }
2805
2806 /*
2807 * Copy the inode security context value to the user.
2808 *
2809 * Permission check is handled by selinux_inode_getxattr hook.
2810 */
2811 static int selinux_inode_getsecurity(const struct inode *inode, const char *name, void **buffer, bool alloc)
2812 {
2813 u32 size;
2814 int error;
2815 char *context = NULL;
2816 struct inode_security_struct *isec = inode->i_security;
2817
2818 if (strcmp(name, XATTR_SELINUX_SUFFIX))
2819 return -EOPNOTSUPP;
2820
2821 /*
2822 * If the caller has CAP_MAC_ADMIN, then get the raw context
2823 * value even if it is not defined by current policy; otherwise,
2824 * use the in-core value under current policy.
2825 * Use the non-auditing forms of the permission checks since
2826 * getxattr may be called by unprivileged processes commonly
2827 * and lack of permission just means that we fall back to the
2828 * in-core context value, not a denial.
2829 */
2830 error = selinux_capable(current, current_cred(), CAP_MAC_ADMIN,
2831 SECURITY_CAP_NOAUDIT);
2832 if (!error)
2833 error = security_sid_to_context_force(isec->sid, &context,
2834 &size);
2835 else
2836 error = security_sid_to_context(isec->sid, &context, &size);
2837 if (error)
2838 return error;
2839 error = size;
2840 if (alloc) {
2841 *buffer = context;
2842 goto out_nofree;
2843 }
2844 kfree(context);
2845 out_nofree:
2846 return error;
2847 }
2848
2849 static int selinux_inode_setsecurity(struct inode *inode, const char *name,
2850 const void *value, size_t size, int flags)
2851 {
2852 struct inode_security_struct *isec = inode->i_security;
2853 u32 newsid;
2854 int rc;
2855
2856 if (strcmp(name, XATTR_SELINUX_SUFFIX))
2857 return -EOPNOTSUPP;
2858
2859 if (!value || !size)
2860 return -EACCES;
2861
2862 rc = security_context_to_sid((void *)value, size, &newsid);
2863 if (rc)
2864 return rc;
2865
2866 isec->sid = newsid;
2867 isec->initialized = 1;
2868 return 0;
2869 }
2870
2871 static int selinux_inode_listsecurity(struct inode *inode, char *buffer, size_t buffer_size)
2872 {
2873 const int len = sizeof(XATTR_NAME_SELINUX);
2874 if (buffer && len <= buffer_size)
2875 memcpy(buffer, XATTR_NAME_SELINUX, len);
2876 return len;
2877 }
2878
2879 static void selinux_inode_getsecid(const struct inode *inode, u32 *secid)
2880 {
2881 struct inode_security_struct *isec = inode->i_security;
2882 *secid = isec->sid;
2883 }
2884
2885 /* file security operations */
2886
2887 static int selinux_revalidate_file_permission(struct file *file, int mask)
2888 {
2889 const struct cred *cred = current_cred();
2890 struct inode *inode = file->f_path.dentry->d_inode;
2891
2892 /* file_mask_to_av won't add FILE__WRITE if MAY_APPEND is set */
2893 if ((file->f_flags & O_APPEND) && (mask & MAY_WRITE))
2894 mask |= MAY_APPEND;
2895
2896 return file_has_perm(cred, file,
2897 file_mask_to_av(inode->i_mode, mask));
2898 }
2899
2900 static int selinux_file_permission(struct file *file, int mask)
2901 {
2902 struct inode *inode = file->f_path.dentry->d_inode;
2903 struct file_security_struct *fsec = file->f_security;
2904 struct inode_security_struct *isec = inode->i_security;
2905 u32 sid = current_sid();
2906
2907 if (!mask)
2908 /* No permission to check. Existence test. */
2909 return 0;
2910
2911 if (sid == fsec->sid && fsec->isid == isec->sid &&
2912 fsec->pseqno == avc_policy_seqno())
2913 /* No change since dentry_open check. */
2914 return 0;
2915
2916 return selinux_revalidate_file_permission(file, mask);
2917 }
2918
2919 static int selinux_file_alloc_security(struct file *file)
2920 {
2921 return file_alloc_security(file);
2922 }
2923
2924 static void selinux_file_free_security(struct file *file)
2925 {
2926 file_free_security(file);
2927 }
2928
2929 static int selinux_file_ioctl(struct file *file, unsigned int cmd,
2930 unsigned long arg)
2931 {
2932 const struct cred *cred = current_cred();
2933 u32 av = 0;
2934
2935 if (_IOC_DIR(cmd) & _IOC_WRITE)
2936 av |= FILE__WRITE;
2937 if (_IOC_DIR(cmd) & _IOC_READ)
2938 av |= FILE__READ;
2939 if (!av)
2940 av = FILE__IOCTL;
2941
2942 return file_has_perm(cred, file, av);
2943 }
2944
2945 static int default_noexec;
2946
2947 static int file_map_prot_check(struct file *file, unsigned long prot, int shared)
2948 {
2949 const struct cred *cred = current_cred();
2950 int rc = 0;
2951
2952 if (default_noexec &&
2953 (prot & PROT_EXEC) && (!file || (!shared && (prot & PROT_WRITE)))) {
2954 /*
2955 * We are making executable an anonymous mapping or a
2956 * private file mapping that will also be writable.
2957 * This has an additional check.
2958 */
2959 rc = cred_has_perm(cred, cred, PROCESS__EXECMEM);
2960 if (rc)
2961 goto error;
2962 }
2963
2964 if (file) {
2965 /* read access is always possible with a mapping */
2966 u32 av = FILE__READ;
2967
2968 /* write access only matters if the mapping is shared */
2969 if (shared && (prot & PROT_WRITE))
2970 av |= FILE__WRITE;
2971
2972 if (prot & PROT_EXEC)
2973 av |= FILE__EXECUTE;
2974
2975 return file_has_perm(cred, file, av);
2976 }
2977
2978 error:
2979 return rc;
2980 }
2981
2982 static int selinux_file_mmap(struct file *file, unsigned long reqprot,
2983 unsigned long prot, unsigned long flags,
2984 unsigned long addr, unsigned long addr_only)
2985 {
2986 int rc = 0;
2987 u32 sid = current_sid();
2988
2989 /*
2990 * notice that we are intentionally putting the SELinux check before
2991 * the secondary cap_file_mmap check. This is such a likely attempt
2992 * at bad behaviour/exploit that we always want to get the AVC, even
2993 * if DAC would have also denied the operation.
2994 */
2995 if (addr < CONFIG_LSM_MMAP_MIN_ADDR) {
2996 rc = avc_has_perm(sid, sid, SECCLASS_MEMPROTECT,
2997 MEMPROTECT__MMAP_ZERO, NULL);
2998 if (rc)
2999 return rc;
3000 }
3001
3002 /* do DAC check on address space usage */
3003 rc = cap_file_mmap(file, reqprot, prot, flags, addr, addr_only);
3004 if (rc || addr_only)
3005 return rc;
3006
3007 if (selinux_checkreqprot)
3008 prot = reqprot;
3009
3010 return file_map_prot_check(file, prot,
3011 (flags & MAP_TYPE) == MAP_SHARED);
3012 }
3013
3014 static int selinux_file_mprotect(struct vm_area_struct *vma,
3015 unsigned long reqprot,
3016 unsigned long prot)
3017 {
3018 const struct cred *cred = current_cred();
3019
3020 if (selinux_checkreqprot)
3021 prot = reqprot;
3022
3023 if (default_noexec &&
3024 (prot & PROT_EXEC) && !(vma->vm_flags & VM_EXEC)) {
3025 int rc = 0;
3026 if (vma->vm_start >= vma->vm_mm->start_brk &&
3027 vma->vm_end <= vma->vm_mm->brk) {
3028 rc = cred_has_perm(cred, cred, PROCESS__EXECHEAP);
3029 } else if (!vma->vm_file &&
3030 vma->vm_start <= vma->vm_mm->start_stack &&
3031 vma->vm_end >= vma->vm_mm->start_stack) {
3032 rc = current_has_perm(current, PROCESS__EXECSTACK);
3033 } else if (vma->vm_file && vma->anon_vma) {
3034 /*
3035 * We are making executable a file mapping that has
3036 * had some COW done. Since pages might have been
3037 * written, check ability to execute the possibly
3038 * modified content. This typically should only
3039 * occur for text relocations.
3040 */
3041 rc = file_has_perm(cred, vma->vm_file, FILE__EXECMOD);
3042 }
3043 if (rc)
3044 return rc;
3045 }
3046
3047 return file_map_prot_check(vma->vm_file, prot, vma->vm_flags&VM_SHARED);
3048 }
3049
3050 static int selinux_file_lock(struct file *file, unsigned int cmd)
3051 {
3052 const struct cred *cred = current_cred();
3053
3054 return file_has_perm(cred, file, FILE__LOCK);
3055 }
3056
3057 static int selinux_file_fcntl(struct file *file, unsigned int cmd,
3058 unsigned long arg)
3059 {
3060 const struct cred *cred = current_cred();
3061 int err = 0;
3062
3063 switch (cmd) {
3064 case F_SETFL:
3065 if (!file->f_path.dentry || !file->f_path.dentry->d_inode) {
3066 err = -EINVAL;
3067 break;
3068 }
3069
3070 if ((file->f_flags & O_APPEND) && !(arg & O_APPEND)) {
3071 err = file_has_perm(cred, file, FILE__WRITE);
3072 break;
3073 }
3074 /* fall through */
3075 case F_SETOWN:
3076 case F_SETSIG:
3077 case F_GETFL:
3078 case F_GETOWN:
3079 case F_GETSIG:
3080 /* Just check FD__USE permission */
3081 err = file_has_perm(cred, file, 0);
3082 break;
3083 case F_GETLK:
3084 case F_SETLK:
3085 case F_SETLKW:
3086 #if BITS_PER_LONG == 32
3087 case F_GETLK64:
3088 case F_SETLK64:
3089 case F_SETLKW64:
3090 #endif
3091 if (!file->f_path.dentry || !file->f_path.dentry->d_inode) {
3092 err = -EINVAL;
3093 break;
3094 }
3095 err = file_has_perm(cred, file, FILE__LOCK);
3096 break;
3097 }
3098
3099 return err;
3100 }
3101
3102 static int selinux_file_set_fowner(struct file *file)
3103 {
3104 struct file_security_struct *fsec;
3105
3106 fsec = file->f_security;
3107 fsec->fown_sid = current_sid();
3108
3109 return 0;
3110 }
3111
3112 static int selinux_file_send_sigiotask(struct task_struct *tsk,
3113 struct fown_struct *fown, int signum)
3114 {
3115 struct file *file;
3116 u32 sid = task_sid(tsk);
3117 u32 perm;
3118 struct file_security_struct *fsec;
3119
3120 /* struct fown_struct is never outside the context of a struct file */
3121 file = container_of(fown, struct file, f_owner);
3122
3123 fsec = file->f_security;
3124
3125 if (!signum)
3126 perm = signal_to_av(SIGIO); /* as per send_sigio_to_task */
3127 else
3128 perm = signal_to_av(signum);
3129
3130 return avc_has_perm(fsec->fown_sid, sid,
3131 SECCLASS_PROCESS, perm, NULL);
3132 }
3133
3134 static int selinux_file_receive(struct file *file)
3135 {
3136 const struct cred *cred = current_cred();
3137
3138 return file_has_perm(cred, file, file_to_av(file));
3139 }
3140
3141 static int selinux_dentry_open(struct file *file, const struct cred *cred)
3142 {
3143 struct file_security_struct *fsec;
3144 struct inode *inode;
3145 struct inode_security_struct *isec;
3146
3147 inode = file->f_path.dentry->d_inode;
3148 fsec = file->f_security;
3149 isec = inode->i_security;
3150 /*
3151 * Save inode label and policy sequence number
3152 * at open-time so that selinux_file_permission
3153 * can determine whether revalidation is necessary.
3154 * Task label is already saved in the file security
3155 * struct as its SID.
3156 */
3157 fsec->isid = isec->sid;
3158 fsec->pseqno = avc_policy_seqno();
3159 /*
3160 * Since the inode label or policy seqno may have changed
3161 * between the selinux_inode_permission check and the saving
3162 * of state above, recheck that access is still permitted.
3163 * Otherwise, access might never be revalidated against the
3164 * new inode label or new policy.
3165 * This check is not redundant - do not remove.
3166 */
3167 return inode_has_perm(cred, inode, open_file_to_av(file), NULL);
3168 }
3169
3170 /* task security operations */
3171
3172 static int selinux_task_create(unsigned long clone_flags)
3173 {
3174 return current_has_perm(current, PROCESS__FORK);
3175 }
3176
3177 /*
3178 * allocate the SELinux part of blank credentials
3179 */
3180 static int selinux_cred_alloc_blank(struct cred *cred, gfp_t gfp)
3181 {
3182 struct task_security_struct *tsec;
3183
3184 tsec = kzalloc(sizeof(struct task_security_struct), gfp);
3185 if (!tsec)
3186 return -ENOMEM;
3187
3188 cred->security = tsec;
3189 return 0;
3190 }
3191
3192 /*
3193 * detach and free the LSM part of a set of credentials
3194 */
3195 static void selinux_cred_free(struct cred *cred)
3196 {
3197 struct task_security_struct *tsec = cred->security;
3198
3199 BUG_ON((unsigned long) cred->security < PAGE_SIZE);
3200 cred->security = (void *) 0x7UL;
3201 kfree(tsec);
3202 }
3203
3204 /*
3205 * prepare a new set of credentials for modification
3206 */
3207 static int selinux_cred_prepare(struct cred *new, const struct cred *old,
3208 gfp_t gfp)
3209 {
3210 const struct task_security_struct *old_tsec;
3211 struct task_security_struct *tsec;
3212
3213 old_tsec = old->security;
3214
3215 tsec = kmemdup(old_tsec, sizeof(struct task_security_struct), gfp);
3216 if (!tsec)
3217 return -ENOMEM;
3218
3219 new->security = tsec;
3220 return 0;
3221 }
3222
3223 /*
3224 * transfer the SELinux data to a blank set of creds
3225 */
3226 static void selinux_cred_transfer(struct cred *new, const struct cred *old)
3227 {
3228 const struct task_security_struct *old_tsec = old->security;
3229 struct task_security_struct *tsec = new->security;
3230
3231 *tsec = *old_tsec;
3232 }
3233
3234 /*
3235 * set the security data for a kernel service
3236 * - all the creation contexts are set to unlabelled
3237 */
3238 static int selinux_kernel_act_as(struct cred *new, u32 secid)
3239 {
3240 struct task_security_struct *tsec = new->security;
3241 u32 sid = current_sid();
3242 int ret;
3243
3244 ret = avc_has_perm(sid, secid,
3245 SECCLASS_KERNEL_SERVICE,
3246 KERNEL_SERVICE__USE_AS_OVERRIDE,
3247 NULL);
3248 if (ret == 0) {
3249 tsec->sid = secid;
3250 tsec->create_sid = 0;
3251 tsec->keycreate_sid = 0;
3252 tsec->sockcreate_sid = 0;
3253 }
3254 return ret;
3255 }
3256
3257 /*
3258 * set the file creation context in a security record to the same as the
3259 * objective context of the specified inode
3260 */
3261 static int selinux_kernel_create_files_as(struct cred *new, struct inode *inode)
3262 {
3263 struct inode_security_struct *isec = inode->i_security;
3264 struct task_security_struct *tsec = new->security;
3265 u32 sid = current_sid();
3266 int ret;
3267
3268 ret = avc_has_perm(sid, isec->sid,
3269 SECCLASS_KERNEL_SERVICE,
3270 KERNEL_SERVICE__CREATE_FILES_AS,
3271 NULL);
3272
3273 if (ret == 0)
3274 tsec->create_sid = isec->sid;
3275 return ret;
3276 }
3277
3278 static int selinux_kernel_module_request(char *kmod_name)
3279 {
3280 u32 sid;
3281 struct common_audit_data ad;
3282
3283 sid = task_sid(current);
3284
3285 COMMON_AUDIT_DATA_INIT(&ad, KMOD);
3286 ad.u.kmod_name = kmod_name;
3287
3288 return avc_has_perm(sid, SECINITSID_KERNEL, SECCLASS_SYSTEM,
3289 SYSTEM__MODULE_REQUEST, &ad);
3290 }
3291
3292 static int selinux_task_setpgid(struct task_struct *p, pid_t pgid)
3293 {
3294 return current_has_perm(p, PROCESS__SETPGID);
3295 }
3296
3297 static int selinux_task_getpgid(struct task_struct *p)
3298 {
3299 return current_has_perm(p, PROCESS__GETPGID);
3300 }
3301
3302 static int selinux_task_getsid(struct task_struct *p)
3303 {
3304 return current_has_perm(p, PROCESS__GETSESSION);
3305 }
3306
3307 static void selinux_task_getsecid(struct task_struct *p, u32 *secid)
3308 {
3309 *secid = task_sid(p);
3310 }
3311
3312 static int selinux_task_setnice(struct task_struct *p, int nice)
3313 {
3314 int rc;
3315
3316 rc = cap_task_setnice(p, nice);
3317 if (rc)
3318 return rc;
3319
3320 return current_has_perm(p, PROCESS__SETSCHED);
3321 }
3322
3323 static int selinux_task_setioprio(struct task_struct *p, int ioprio)
3324 {
3325 int rc;
3326
3327 rc = cap_task_setioprio(p, ioprio);
3328 if (rc)
3329 return rc;
3330
3331 return current_has_perm(p, PROCESS__SETSCHED);
3332 }
3333
3334 static int selinux_task_getioprio(struct task_struct *p)
3335 {
3336 return current_has_perm(p, PROCESS__GETSCHED);
3337 }
3338
3339 static int selinux_task_setrlimit(struct task_struct *p, unsigned int resource,
3340 struct rlimit *new_rlim)
3341 {
3342 struct rlimit *old_rlim = p->signal->rlim + resource;
3343
3344 /* Control the ability to change the hard limit (whether
3345 lowering or raising it), so that the hard limit can
3346 later be used as a safe reset point for the soft limit
3347 upon context transitions. See selinux_bprm_committing_creds. */
3348 if (old_rlim->rlim_max != new_rlim->rlim_max)
3349 return current_has_perm(p, PROCESS__SETRLIMIT);
3350
3351 return 0;
3352 }
3353
3354 static int selinux_task_setscheduler(struct task_struct *p, int policy, struct sched_param *lp)
3355 {
3356 int rc;
3357
3358 rc = cap_task_setscheduler(p, policy, lp);
3359 if (rc)
3360 return rc;
3361
3362 return current_has_perm(p, PROCESS__SETSCHED);
3363 }
3364
3365 static int selinux_task_getscheduler(struct task_struct *p)
3366 {
3367 return current_has_perm(p, PROCESS__GETSCHED);
3368 }
3369
3370 static int selinux_task_movememory(struct task_struct *p)
3371 {
3372 return current_has_perm(p, PROCESS__SETSCHED);
3373 }
3374
3375 static int selinux_task_kill(struct task_struct *p, struct siginfo *info,
3376 int sig, u32 secid)
3377 {
3378 u32 perm;
3379 int rc;
3380
3381 if (!sig)
3382 perm = PROCESS__SIGNULL; /* null signal; existence test */
3383 else
3384 perm = signal_to_av(sig);
3385 if (secid)
3386 rc = avc_has_perm(secid, task_sid(p),
3387 SECCLASS_PROCESS, perm, NULL);
3388 else
3389 rc = current_has_perm(p, perm);
3390 return rc;
3391 }
3392
3393 static int selinux_task_wait(struct task_struct *p)
3394 {
3395 return task_has_perm(p, current, PROCESS__SIGCHLD);
3396 }
3397
3398 static void selinux_task_to_inode(struct task_struct *p,
3399 struct inode *inode)
3400 {
3401 struct inode_security_struct *isec = inode->i_security;
3402 u32 sid = task_sid(p);
3403
3404 isec->sid = sid;
3405 isec->initialized = 1;
3406 }
3407
3408 /* Returns error only if unable to parse addresses */
3409 static int selinux_parse_skb_ipv4(struct sk_buff *skb,
3410 struct common_audit_data *ad, u8 *proto)
3411 {
3412 int offset, ihlen, ret = -EINVAL;
3413 struct iphdr _iph, *ih;
3414
3415 offset = skb_network_offset(skb);
3416 ih = skb_header_pointer(skb, offset, sizeof(_iph), &_iph);
3417 if (ih == NULL)
3418 goto out;
3419
3420 ihlen = ih->ihl * 4;
3421 if (ihlen < sizeof(_iph))
3422 goto out;
3423
3424 ad->u.net.v4info.saddr = ih->saddr;
3425 ad->u.net.v4info.daddr = ih->daddr;
3426 ret = 0;
3427
3428 if (proto)
3429 *proto = ih->protocol;
3430
3431 switch (ih->protocol) {
3432 case IPPROTO_TCP: {
3433 struct tcphdr _tcph, *th;
3434
3435 if (ntohs(ih->frag_off) & IP_OFFSET)
3436 break;
3437
3438 offset += ihlen;
3439 th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph);
3440 if (th == NULL)
3441 break;
3442
3443 ad->u.net.sport = th->source;
3444 ad->u.net.dport = th->dest;
3445 break;
3446 }
3447
3448 case IPPROTO_UDP: {
3449 struct udphdr _udph, *uh;
3450
3451 if (ntohs(ih->frag_off) & IP_OFFSET)
3452 break;
3453
3454 offset += ihlen;
3455 uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph);
3456 if (uh == NULL)
3457 break;
3458
3459 ad->u.net.sport = uh->source;
3460 ad->u.net.dport = uh->dest;
3461 break;
3462 }
3463
3464 case IPPROTO_DCCP: {
3465 struct dccp_hdr _dccph, *dh;
3466
3467 if (ntohs(ih->frag_off) & IP_OFFSET)
3468 break;
3469
3470 offset += ihlen;
3471 dh = skb_header_pointer(skb, offset, sizeof(_dccph), &_dccph);
3472 if (dh == NULL)
3473 break;
3474
3475 ad->u.net.sport = dh->dccph_sport;
3476 ad->u.net.dport = dh->dccph_dport;
3477 break;
3478 }
3479
3480 default:
3481 break;
3482 }
3483 out:
3484 return ret;
3485 }
3486
3487 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
3488
3489 /* Returns error only if unable to parse addresses */
3490 static int selinux_parse_skb_ipv6(struct sk_buff *skb,
3491 struct common_audit_data *ad, u8 *proto)
3492 {
3493 u8 nexthdr;
3494 int ret = -EINVAL, offset;
3495 struct ipv6hdr _ipv6h, *ip6;
3496
3497 offset = skb_network_offset(skb);
3498 ip6 = skb_header_pointer(skb, offset, sizeof(_ipv6h), &_ipv6h);
3499 if (ip6 == NULL)
3500 goto out;
3501
3502 ipv6_addr_copy(&ad->u.net.v6info.saddr, &ip6->saddr);
3503 ipv6_addr_copy(&ad->u.net.v6info.daddr, &ip6->daddr);
3504 ret = 0;
3505
3506 nexthdr = ip6->nexthdr;
3507 offset += sizeof(_ipv6h);
3508 offset = ipv6_skip_exthdr(skb, offset, &nexthdr);
3509 if (offset < 0)
3510 goto out;
3511
3512 if (proto)
3513 *proto = nexthdr;
3514
3515 switch (nexthdr) {
3516 case IPPROTO_TCP: {
3517 struct tcphdr _tcph, *th;
3518
3519 th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph);
3520 if (th == NULL)
3521 break;
3522
3523 ad->u.net.sport = th->source;
3524 ad->u.net.dport = th->dest;
3525 break;
3526 }
3527
3528 case IPPROTO_UDP: {
3529 struct udphdr _udph, *uh;
3530
3531 uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph);
3532 if (uh == NULL)
3533 break;
3534
3535 ad->u.net.sport = uh->source;
3536 ad->u.net.dport = uh->dest;
3537 break;
3538 }
3539
3540 case IPPROTO_DCCP: {
3541 struct dccp_hdr _dccph, *dh;
3542
3543 dh = skb_header_pointer(skb, offset, sizeof(_dccph), &_dccph);
3544 if (dh == NULL)
3545 break;
3546
3547 ad->u.net.sport = dh->dccph_sport;
3548 ad->u.net.dport = dh->dccph_dport;
3549 break;
3550 }
3551
3552 /* includes fragments */
3553 default:
3554 break;
3555 }
3556 out:
3557 return ret;
3558 }
3559
3560 #endif /* IPV6 */
3561
3562 static int selinux_parse_skb(struct sk_buff *skb, struct common_audit_data *ad,
3563 char **_addrp, int src, u8 *proto)
3564 {
3565 char *addrp;
3566 int ret;
3567
3568 switch (ad->u.net.family) {
3569 case PF_INET:
3570 ret = selinux_parse_skb_ipv4(skb, ad, proto);
3571 if (ret)
3572 goto parse_error;
3573 addrp = (char *)(src ? &ad->u.net.v4info.saddr :
3574 &ad->u.net.v4info.daddr);
3575 goto okay;
3576
3577 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
3578 case PF_INET6:
3579 ret = selinux_parse_skb_ipv6(skb, ad, proto);
3580 if (ret)
3581 goto parse_error;
3582 addrp = (char *)(src ? &ad->u.net.v6info.saddr :
3583 &ad->u.net.v6info.daddr);
3584 goto okay;
3585 #endif /* IPV6 */
3586 default:
3587 addrp = NULL;
3588 goto okay;
3589 }
3590
3591 parse_error:
3592 printk(KERN_WARNING
3593 "SELinux: failure in selinux_parse_skb(),"
3594 " unable to parse packet\n");
3595 return ret;
3596
3597 okay:
3598 if (_addrp)
3599 *_addrp = addrp;
3600 return 0;
3601 }
3602
3603 /**
3604 * selinux_skb_peerlbl_sid - Determine the peer label of a packet
3605 * @skb: the packet
3606 * @family: protocol family
3607 * @sid: the packet's peer label SID
3608 *
3609 * Description:
3610 * Check the various different forms of network peer labeling and determine
3611 * the peer label/SID for the packet; most of the magic actually occurs in
3612 * the security server function security_net_peersid_cmp(). The function
3613 * returns zero if the value in @sid is valid (although it may be SECSID_NULL)
3614 * or -EACCES if @sid is invalid due to inconsistencies with the different
3615 * peer labels.
3616 *
3617 */
3618 static int selinux_skb_peerlbl_sid(struct sk_buff *skb, u16 family, u32 *sid)
3619 {
3620 int err;
3621 u32 xfrm_sid;
3622 u32 nlbl_sid;
3623 u32 nlbl_type;
3624
3625 selinux_skb_xfrm_sid(skb, &xfrm_sid);
3626 selinux_netlbl_skbuff_getsid(skb, family, &nlbl_type, &nlbl_sid);
3627
3628 err = security_net_peersid_resolve(nlbl_sid, nlbl_type, xfrm_sid, sid);
3629 if (unlikely(err)) {
3630 printk(KERN_WARNING
3631 "SELinux: failure in selinux_skb_peerlbl_sid(),"
3632 " unable to determine packet's peer label\n");
3633 return -EACCES;
3634 }
3635
3636 return 0;
3637 }
3638
3639 /* socket security operations */
3640
3641 static u32 socket_sockcreate_sid(const struct task_security_struct *tsec)
3642 {
3643 return tsec->sockcreate_sid ? : tsec->sid;
3644 }
3645
3646 static int sock_has_perm(struct task_struct *task, struct sock *sk, u32 perms)
3647 {
3648 struct sk_security_struct *sksec = sk->sk_security;
3649 struct common_audit_data ad;
3650 u32 tsid = task_sid(task);
3651
3652 if (sksec->sid == SECINITSID_KERNEL)
3653 return 0;
3654
3655 COMMON_AUDIT_DATA_INIT(&ad, NET);
3656 ad.u.net.sk = sk;
3657
3658 return avc_has_perm(tsid, sksec->sid, sksec->sclass, perms, &ad);
3659 }
3660
3661 static int selinux_socket_create(int family, int type,
3662 int protocol, int kern)
3663 {
3664 const struct task_security_struct *tsec = current_security();
3665 u32 newsid;
3666 u16 secclass;
3667
3668 if (kern)
3669 return 0;
3670
3671 newsid = socket_sockcreate_sid(tsec);
3672 secclass = socket_type_to_security_class(family, type, protocol);
3673 return avc_has_perm(tsec->sid, newsid, secclass, SOCKET__CREATE, NULL);
3674 }
3675
3676 static int selinux_socket_post_create(struct socket *sock, int family,
3677 int type, int protocol, int kern)
3678 {
3679 const struct task_security_struct *tsec = current_security();
3680 struct inode_security_struct *isec = SOCK_INODE(sock)->i_security;
3681 struct sk_security_struct *sksec;
3682 int err = 0;
3683
3684 if (kern)
3685 isec->sid = SECINITSID_KERNEL;
3686 else
3687 isec->sid = socket_sockcreate_sid(tsec);
3688
3689 isec->sclass = socket_type_to_security_class(family, type, protocol);
3690 isec->initialized = 1;
3691
3692 if (sock->sk) {
3693 sksec = sock->sk->sk_security;
3694 sksec->sid = isec->sid;
3695 sksec->sclass = isec->sclass;
3696 err = selinux_netlbl_socket_post_create(sock->sk, family);
3697 }
3698
3699 return err;
3700 }
3701
3702 /* Range of port numbers used to automatically bind.
3703 Need to determine whether we should perform a name_bind
3704 permission check between the socket and the port number. */
3705
3706 static int selinux_socket_bind(struct socket *sock, struct sockaddr *address, int addrlen)
3707 {
3708 struct sock *sk = sock->sk;
3709 u16 family;
3710 int err;
3711
3712 err = sock_has_perm(current, sk, SOCKET__BIND);
3713 if (err)
3714 goto out;
3715
3716 /*
3717 * If PF_INET or PF_INET6, check name_bind permission for the port.
3718 * Multiple address binding for SCTP is not supported yet: we just
3719 * check the first address now.
3720 */
3721 family = sk->sk_family;
3722 if (family == PF_INET || family == PF_INET6) {
3723 char *addrp;
3724 struct sk_security_struct *sksec = sk->sk_security;
3725 struct common_audit_data ad;
3726 struct sockaddr_in *addr4 = NULL;
3727 struct sockaddr_in6 *addr6 = NULL;
3728 unsigned short snum;
3729 u32 sid, node_perm;
3730
3731 if (family == PF_INET) {
3732 addr4 = (struct sockaddr_in *)address;
3733 snum = ntohs(addr4->sin_port);
3734 addrp = (char *)&addr4->sin_addr.s_addr;
3735 } else {
3736 addr6 = (struct sockaddr_in6 *)address;
3737 snum = ntohs(addr6->sin6_port);
3738 addrp = (char *)&addr6->sin6_addr.s6_addr;
3739 }
3740
3741 if (snum) {
3742 int low, high;
3743
3744 inet_get_local_port_range(&low, &high);
3745
3746 if (snum < max(PROT_SOCK, low) || snum > high) {
3747 err = sel_netport_sid(sk->sk_protocol,
3748 snum, &sid);
3749 if (err)
3750 goto out;
3751 COMMON_AUDIT_DATA_INIT(&ad, NET);
3752 ad.u.net.sport = htons(snum);
3753 ad.u.net.family = family;
3754 err = avc_has_perm(sksec->sid, sid,
3755 sksec->sclass,
3756 SOCKET__NAME_BIND, &ad);
3757 if (err)
3758 goto out;
3759 }
3760 }
3761
3762 switch (sksec->sclass) {
3763 case SECCLASS_TCP_SOCKET:
3764 node_perm = TCP_SOCKET__NODE_BIND;
3765 break;
3766
3767 case SECCLASS_UDP_SOCKET:
3768 node_perm = UDP_SOCKET__NODE_BIND;
3769 break;
3770
3771 case SECCLASS_DCCP_SOCKET:
3772 node_perm = DCCP_SOCKET__NODE_BIND;
3773 break;
3774
3775 default:
3776 node_perm = RAWIP_SOCKET__NODE_BIND;
3777 break;
3778 }
3779
3780 err = sel_netnode_sid(addrp, family, &sid);
3781 if (err)
3782 goto out;
3783
3784 COMMON_AUDIT_DATA_INIT(&ad, NET);
3785 ad.u.net.sport = htons(snum);
3786 ad.u.net.family = family;
3787
3788 if (family == PF_INET)
3789 ad.u.net.v4info.saddr = addr4->sin_addr.s_addr;
3790 else
3791 ipv6_addr_copy(&ad.u.net.v6info.saddr, &addr6->sin6_addr);
3792
3793 err = avc_has_perm(sksec->sid, sid,
3794 sksec->sclass, node_perm, &ad);
3795 if (err)
3796 goto out;
3797 }
3798 out:
3799 return err;
3800 }
3801
3802 static int selinux_socket_connect(struct socket *sock, struct sockaddr *address, int addrlen)
3803 {
3804 struct sock *sk = sock->sk;
3805 struct sk_security_struct *sksec = sk->sk_security;
3806 int err;
3807
3808 err = sock_has_perm(current, sk, SOCKET__CONNECT);
3809 if (err)
3810 return err;
3811
3812 /*
3813 * If a TCP or DCCP socket, check name_connect permission for the port.
3814 */
3815 if (sksec->sclass == SECCLASS_TCP_SOCKET ||
3816 sksec->sclass == SECCLASS_DCCP_SOCKET) {
3817 struct common_audit_data ad;
3818 struct sockaddr_in *addr4 = NULL;
3819 struct sockaddr_in6 *addr6 = NULL;
3820 unsigned short snum;
3821 u32 sid, perm;
3822
3823 if (sk->sk_family == PF_INET) {
3824 addr4 = (struct sockaddr_in *)address;
3825 if (addrlen < sizeof(struct sockaddr_in))
3826 return -EINVAL;
3827 snum = ntohs(addr4->sin_port);
3828 } else {
3829 addr6 = (struct sockaddr_in6 *)address;
3830 if (addrlen < SIN6_LEN_RFC2133)
3831 return -EINVAL;
3832 snum = ntohs(addr6->sin6_port);
3833 }
3834
3835 err = sel_netport_sid(sk->sk_protocol, snum, &sid);
3836 if (err)
3837 goto out;
3838
3839 perm = (sksec->sclass == SECCLASS_TCP_SOCKET) ?
3840 TCP_SOCKET__NAME_CONNECT : DCCP_SOCKET__NAME_CONNECT;
3841
3842 COMMON_AUDIT_DATA_INIT(&ad, NET);
3843 ad.u.net.dport = htons(snum);
3844 ad.u.net.family = sk->sk_family;
3845 err = avc_has_perm(sksec->sid, sid, sksec->sclass, perm, &ad);
3846 if (err)
3847 goto out;
3848 }
3849
3850 err = selinux_netlbl_socket_connect(sk, address);
3851
3852 out:
3853 return err;
3854 }
3855
3856 static int selinux_socket_listen(struct socket *sock, int backlog)
3857 {
3858 return sock_has_perm(current, sock->sk, SOCKET__LISTEN);
3859 }
3860
3861 static int selinux_socket_accept(struct socket *sock, struct socket *newsock)
3862 {
3863 int err;
3864 struct inode_security_struct *isec;
3865 struct inode_security_struct *newisec;
3866
3867 err = sock_has_perm(current, sock->sk, SOCKET__ACCEPT);
3868 if (err)
3869 return err;
3870
3871 newisec = SOCK_INODE(newsock)->i_security;
3872
3873 isec = SOCK_INODE(sock)->i_security;
3874 newisec->sclass = isec->sclass;
3875 newisec->sid = isec->sid;
3876 newisec->initialized = 1;
3877
3878 return 0;
3879 }
3880
3881 static int selinux_socket_sendmsg(struct socket *sock, struct msghdr *msg,
3882 int size)
3883 {
3884 return sock_has_perm(current, sock->sk, SOCKET__WRITE);
3885 }
3886
3887 static int selinux_socket_recvmsg(struct socket *sock, struct msghdr *msg,
3888 int size, int flags)
3889 {
3890 return sock_has_perm(current, sock->sk, SOCKET__READ);
3891 }
3892
3893 static int selinux_socket_getsockname(struct socket *sock)
3894 {
3895 return sock_has_perm(current, sock->sk, SOCKET__GETATTR);
3896 }
3897
3898 static int selinux_socket_getpeername(struct socket *sock)
3899 {
3900 return sock_has_perm(current, sock->sk, SOCKET__GETATTR);
3901 }
3902
3903 static int selinux_socket_setsockopt(struct socket *sock, int level, int optname)
3904 {
3905 int err;
3906
3907 err = sock_has_perm(current, sock->sk, SOCKET__SETOPT);
3908 if (err)
3909 return err;
3910
3911 return selinux_netlbl_socket_setsockopt(sock, level, optname);
3912 }
3913
3914 static int selinux_socket_getsockopt(struct socket *sock, int level,
3915 int optname)
3916 {
3917 return sock_has_perm(current, sock->sk, SOCKET__GETOPT);
3918 }
3919
3920 static int selinux_socket_shutdown(struct socket *sock, int how)
3921 {
3922 return sock_has_perm(current, sock->sk, SOCKET__SHUTDOWN);
3923 }
3924
3925 static int selinux_socket_unix_stream_connect(struct socket *sock,
3926 struct socket *other,
3927 struct sock *newsk)
3928 {
3929 struct sk_security_struct *sksec_sock = sock->sk->sk_security;
3930 struct sk_security_struct *sksec_other = other->sk->sk_security;
3931 struct sk_security_struct *sksec_new = newsk->sk_security;
3932 struct common_audit_data ad;
3933 int err;
3934
3935 COMMON_AUDIT_DATA_INIT(&ad, NET);
3936 ad.u.net.sk = other->sk;
3937
3938 err = avc_has_perm(sksec_sock->sid, sksec_other->sid,
3939 sksec_other->sclass,
3940 UNIX_STREAM_SOCKET__CONNECTTO, &ad);
3941 if (err)
3942 return err;
3943
3944 /* server child socket */
3945 sksec_new->peer_sid = sksec_sock->sid;
3946 err = security_sid_mls_copy(sksec_other->sid, sksec_sock->sid,
3947 &sksec_new->sid);
3948 if (err)
3949 return err;
3950
3951 /* connecting socket */
3952 sksec_sock->peer_sid = sksec_new->sid;
3953
3954 return 0;
3955 }
3956
3957 static int selinux_socket_unix_may_send(struct socket *sock,
3958 struct socket *other)
3959 {
3960 struct sk_security_struct *ssec = sock->sk->sk_security;
3961 struct sk_security_struct *osec = other->sk->sk_security;
3962 struct common_audit_data ad;
3963
3964 COMMON_AUDIT_DATA_INIT(&ad, NET);
3965 ad.u.net.sk = other->sk;
3966
3967 return avc_has_perm(ssec->sid, osec->sid, osec->sclass, SOCKET__SENDTO,
3968 &ad);
3969 }
3970
3971 static int selinux_inet_sys_rcv_skb(int ifindex, char *addrp, u16 family,
3972 u32 peer_sid,
3973 struct common_audit_data *ad)
3974 {
3975 int err;
3976 u32 if_sid;
3977 u32 node_sid;
3978
3979 err = sel_netif_sid(ifindex, &if_sid);
3980 if (err)
3981 return err;
3982 err = avc_has_perm(peer_sid, if_sid,
3983 SECCLASS_NETIF, NETIF__INGRESS, ad);
3984 if (err)
3985 return err;
3986
3987 err = sel_netnode_sid(addrp, family, &node_sid);
3988 if (err)
3989 return err;
3990 return avc_has_perm(peer_sid, node_sid,
3991 SECCLASS_NODE, NODE__RECVFROM, ad);
3992 }
3993
3994 static int selinux_sock_rcv_skb_compat(struct sock *sk, struct sk_buff *skb,
3995 u16 family)
3996 {
3997 int err = 0;
3998 struct sk_security_struct *sksec = sk->sk_security;
3999 u32 peer_sid;
4000 u32 sk_sid = sksec->sid;
4001 struct common_audit_data ad;
4002 char *addrp;
4003
4004 COMMON_AUDIT_DATA_INIT(&ad, NET);
4005 ad.u.net.netif = skb->skb_iif;
4006 ad.u.net.family = family;
4007 err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL);
4008 if (err)
4009 return err;
4010
4011 if (selinux_secmark_enabled()) {
4012 err = avc_has_perm(sk_sid, skb->secmark, SECCLASS_PACKET,
4013 PACKET__RECV, &ad);
4014 if (err)
4015 return err;
4016 }
4017
4018 if (selinux_policycap_netpeer) {
4019 err = selinux_skb_peerlbl_sid(skb, family, &peer_sid);
4020 if (err)
4021 return err;
4022 err = avc_has_perm(sk_sid, peer_sid,
4023 SECCLASS_PEER, PEER__RECV, &ad);
4024 if (err)
4025 selinux_netlbl_err(skb, err, 0);
4026 } else {
4027 err = selinux_netlbl_sock_rcv_skb(sksec, skb, family, &ad);
4028 if (err)
4029 return err;
4030 err = selinux_xfrm_sock_rcv_skb(sksec->sid, skb, &ad);
4031 }
4032
4033 return err;
4034 }
4035
4036 static int selinux_socket_sock_rcv_skb(struct sock *sk, struct sk_buff *skb)
4037 {
4038 int err;
4039 struct sk_security_struct *sksec = sk->sk_security;
4040 u16 family = sk->sk_family;
4041 u32 sk_sid = sksec->sid;
4042 struct common_audit_data ad;
4043 char *addrp;
4044 u8 secmark_active;
4045 u8 peerlbl_active;
4046
4047 if (family != PF_INET && family != PF_INET6)
4048 return 0;
4049
4050 /* Handle mapped IPv4 packets arriving via IPv6 sockets */
4051 if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
4052 family = PF_INET;
4053
4054 /* If any sort of compatibility mode is enabled then handoff processing
4055 * to the selinux_sock_rcv_skb_compat() function to deal with the
4056 * special handling. We do this in an attempt to keep this function
4057 * as fast and as clean as possible. */
4058 if (!selinux_policycap_netpeer)
4059 return selinux_sock_rcv_skb_compat(sk, skb, family);
4060
4061 secmark_active = selinux_secmark_enabled();
4062 peerlbl_active = netlbl_enabled() || selinux_xfrm_enabled();
4063 if (!secmark_active && !peerlbl_active)
4064 return 0;
4065
4066 COMMON_AUDIT_DATA_INIT(&ad, NET);
4067 ad.u.net.netif = skb->skb_iif;
4068 ad.u.net.family = family;
4069 err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL);
4070 if (err)
4071 return err;
4072
4073 if (peerlbl_active) {
4074 u32 peer_sid;
4075
4076 err = selinux_skb_peerlbl_sid(skb, family, &peer_sid);
4077 if (err)
4078 return err;
4079 err = selinux_inet_sys_rcv_skb(skb->skb_iif, addrp, family,
4080 peer_sid, &ad);
4081 if (err) {
4082 selinux_netlbl_err(skb, err, 0);
4083 return err;
4084 }
4085 err = avc_has_perm(sk_sid, peer_sid, SECCLASS_PEER,
4086 PEER__RECV, &ad);
4087 if (err)
4088 selinux_netlbl_err(skb, err, 0);
4089 }
4090
4091 if (secmark_active) {
4092 err = avc_has_perm(sk_sid, skb->secmark, SECCLASS_PACKET,
4093 PACKET__RECV, &ad);
4094 if (err)
4095 return err;
4096 }
4097
4098 return err;
4099 }
4100
4101 static int selinux_socket_getpeersec_stream(struct socket *sock, char __user *optval,
4102 int __user *optlen, unsigned len)
4103 {
4104 int err = 0;
4105 char *scontext;
4106 u32 scontext_len;
4107 struct sk_security_struct *sksec = sock->sk->sk_security;
4108 u32 peer_sid = SECSID_NULL;
4109
4110 if (sksec->sclass == SECCLASS_UNIX_STREAM_SOCKET ||
4111 sksec->sclass == SECCLASS_TCP_SOCKET)
4112 peer_sid = sksec->peer_sid;
4113 if (peer_sid == SECSID_NULL)
4114 return -ENOPROTOOPT;
4115
4116 err = security_sid_to_context(peer_sid, &scontext, &scontext_len);
4117 if (err)
4118 return err;
4119
4120 if (scontext_len > len) {
4121 err = -ERANGE;
4122 goto out_len;
4123 }
4124
4125 if (copy_to_user(optval, scontext, scontext_len))
4126 err = -EFAULT;
4127
4128 out_len:
4129 if (put_user(scontext_len, optlen))
4130 err = -EFAULT;
4131 kfree(scontext);
4132 return err;
4133 }
4134
4135 static int selinux_socket_getpeersec_dgram(struct socket *sock, struct sk_buff *skb, u32 *secid)
4136 {
4137 u32 peer_secid = SECSID_NULL;
4138 u16 family;
4139
4140 if (skb && skb->protocol == htons(ETH_P_IP))
4141 family = PF_INET;
4142 else if (skb && skb->protocol == htons(ETH_P_IPV6))
4143 family = PF_INET6;
4144 else if (sock)
4145 family = sock->sk->sk_family;
4146 else
4147 goto out;
4148
4149 if (sock && family == PF_UNIX)
4150 selinux_inode_getsecid(SOCK_INODE(sock), &peer_secid);
4151 else if (skb)
4152 selinux_skb_peerlbl_sid(skb, family, &peer_secid);
4153
4154 out:
4155 *secid = peer_secid;
4156 if (peer_secid == SECSID_NULL)
4157 return -EINVAL;
4158 return 0;
4159 }
4160
4161 static int selinux_sk_alloc_security(struct sock *sk, int family, gfp_t priority)
4162 {
4163 struct sk_security_struct *sksec;
4164
4165 sksec = kzalloc(sizeof(*sksec), priority);
4166 if (!sksec)
4167 return -ENOMEM;
4168
4169 sksec->peer_sid = SECINITSID_UNLABELED;
4170 sksec->sid = SECINITSID_UNLABELED;
4171 selinux_netlbl_sk_security_reset(sksec);
4172 sk->sk_security = sksec;
4173
4174 return 0;
4175 }
4176
4177 static void selinux_sk_free_security(struct sock *sk)
4178 {
4179 struct sk_security_struct *sksec = sk->sk_security;
4180
4181 sk->sk_security = NULL;
4182 selinux_netlbl_sk_security_free(sksec);
4183 kfree(sksec);
4184 }
4185
4186 static void selinux_sk_clone_security(const struct sock *sk, struct sock *newsk)
4187 {
4188 struct sk_security_struct *sksec = sk->sk_security;
4189 struct sk_security_struct *newsksec = newsk->sk_security;
4190
4191 newsksec->sid = sksec->sid;
4192 newsksec->peer_sid = sksec->peer_sid;
4193 newsksec->sclass = sksec->sclass;
4194
4195 selinux_netlbl_sk_security_reset(newsksec);
4196 }
4197
4198 static void selinux_sk_getsecid(struct sock *sk, u32 *secid)
4199 {
4200 if (!sk)
4201 *secid = SECINITSID_ANY_SOCKET;
4202 else {
4203 struct sk_security_struct *sksec = sk->sk_security;
4204
4205 *secid = sksec->sid;
4206 }
4207 }
4208
4209 static void selinux_sock_graft(struct sock *sk, struct socket *parent)
4210 {
4211 struct inode_security_struct *isec = SOCK_INODE(parent)->i_security;
4212 struct sk_security_struct *sksec = sk->sk_security;
4213
4214 if (sk->sk_family == PF_INET || sk->sk_family == PF_INET6 ||
4215 sk->sk_family == PF_UNIX)
4216 isec->sid = sksec->sid;
4217 sksec->sclass = isec->sclass;
4218 }
4219
4220 static int selinux_inet_conn_request(struct sock *sk, struct sk_buff *skb,
4221 struct request_sock *req)
4222 {
4223 struct sk_security_struct *sksec = sk->sk_security;
4224 int err;
4225 u16 family = sk->sk_family;
4226 u32 newsid;
4227 u32 peersid;
4228
4229 /* handle mapped IPv4 packets arriving via IPv6 sockets */
4230 if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
4231 family = PF_INET;
4232
4233 err = selinux_skb_peerlbl_sid(skb, family, &peersid);
4234 if (err)
4235 return err;
4236 if (peersid == SECSID_NULL) {
4237 req->secid = sksec->sid;
4238 req->peer_secid = SECSID_NULL;
4239 } else {
4240 err = security_sid_mls_copy(sksec->sid, peersid, &newsid);
4241 if (err)
4242 return err;
4243 req->secid = newsid;
4244 req->peer_secid = peersid;
4245 }
4246
4247 return selinux_netlbl_inet_conn_request(req, family);
4248 }
4249
4250 static void selinux_inet_csk_clone(struct sock *newsk,
4251 const struct request_sock *req)
4252 {
4253 struct sk_security_struct *newsksec = newsk->sk_security;
4254
4255 newsksec->sid = req->secid;
4256 newsksec->peer_sid = req->peer_secid;
4257 /* NOTE: Ideally, we should also get the isec->sid for the
4258 new socket in sync, but we don't have the isec available yet.
4259 So we will wait until sock_graft to do it, by which
4260 time it will have been created and available. */
4261
4262 /* We don't need to take any sort of lock here as we are the only
4263 * thread with access to newsksec */
4264 selinux_netlbl_inet_csk_clone(newsk, req->rsk_ops->family);
4265 }
4266
4267 static void selinux_inet_conn_established(struct sock *sk, struct sk_buff *skb)
4268 {
4269 u16 family = sk->sk_family;
4270 struct sk_security_struct *sksec = sk->sk_security;
4271
4272 /* handle mapped IPv4 packets arriving via IPv6 sockets */
4273 if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
4274 family = PF_INET;
4275
4276 selinux_skb_peerlbl_sid(skb, family, &sksec->peer_sid);
4277 }
4278
4279 static void selinux_req_classify_flow(const struct request_sock *req,
4280 struct flowi *fl)
4281 {
4282 fl->secid = req->secid;
4283 }
4284
4285 static int selinux_tun_dev_create(void)
4286 {
4287 u32 sid = current_sid();
4288
4289 /* we aren't taking into account the "sockcreate" SID since the socket
4290 * that is being created here is not a socket in the traditional sense,
4291 * instead it is a private sock, accessible only to the kernel, and
4292 * representing a wide range of network traffic spanning multiple
4293 * connections unlike traditional sockets - check the TUN driver to
4294 * get a better understanding of why this socket is special */
4295
4296 return avc_has_perm(sid, sid, SECCLASS_TUN_SOCKET, TUN_SOCKET__CREATE,
4297 NULL);
4298 }
4299
4300 static void selinux_tun_dev_post_create(struct sock *sk)
4301 {
4302 struct sk_security_struct *sksec = sk->sk_security;
4303
4304 /* we don't currently perform any NetLabel based labeling here and it
4305 * isn't clear that we would want to do so anyway; while we could apply
4306 * labeling without the support of the TUN user the resulting labeled
4307 * traffic from the other end of the connection would almost certainly
4308 * cause confusion to the TUN user that had no idea network labeling
4309 * protocols were being used */
4310
4311 /* see the comments in selinux_tun_dev_create() about why we don't use
4312 * the sockcreate SID here */
4313
4314 sksec->sid = current_sid();
4315 sksec->sclass = SECCLASS_TUN_SOCKET;
4316 }
4317
4318 static int selinux_tun_dev_attach(struct sock *sk)
4319 {
4320 struct sk_security_struct *sksec = sk->sk_security;
4321 u32 sid = current_sid();
4322 int err;
4323
4324 err = avc_has_perm(sid, sksec->sid, SECCLASS_TUN_SOCKET,
4325 TUN_SOCKET__RELABELFROM, NULL);
4326 if (err)
4327 return err;
4328 err = avc_has_perm(sid, sid, SECCLASS_TUN_SOCKET,
4329 TUN_SOCKET__RELABELTO, NULL);
4330 if (err)
4331 return err;
4332
4333 sksec->sid = sid;
4334
4335 return 0;
4336 }
4337
4338 static int selinux_nlmsg_perm(struct sock *sk, struct sk_buff *skb)
4339 {
4340 int err = 0;
4341 u32 perm;
4342 struct nlmsghdr *nlh;
4343 struct sk_security_struct *sksec = sk->sk_security;
4344
4345 if (skb->len < NLMSG_SPACE(0)) {
4346 err = -EINVAL;
4347 goto out;
4348 }
4349 nlh = nlmsg_hdr(skb);
4350
4351 err = selinux_nlmsg_lookup(sksec->sclass, nlh->nlmsg_type, &perm);
4352 if (err) {
4353 if (err == -EINVAL) {
4354 audit_log(current->audit_context, GFP_KERNEL, AUDIT_SELINUX_ERR,
4355 "SELinux: unrecognized netlink message"
4356 " type=%hu for sclass=%hu\n",
4357 nlh->nlmsg_type, sksec->sclass);
4358 if (!selinux_enforcing || security_get_allow_unknown())
4359 err = 0;
4360 }
4361
4362 /* Ignore */
4363 if (err == -ENOENT)
4364 err = 0;
4365 goto out;
4366 }
4367
4368 err = sock_has_perm(current, sk, perm);
4369 out:
4370 return err;
4371 }
4372
4373 #ifdef CONFIG_NETFILTER
4374
4375 static unsigned int selinux_ip_forward(struct sk_buff *skb, int ifindex,
4376 u16 family)
4377 {
4378 int err;
4379 char *addrp;
4380 u32 peer_sid;
4381 struct common_audit_data ad;
4382 u8 secmark_active;
4383 u8 netlbl_active;
4384 u8 peerlbl_active;
4385
4386 if (!selinux_policycap_netpeer)
4387 return NF_ACCEPT;
4388
4389 secmark_active = selinux_secmark_enabled();
4390 netlbl_active = netlbl_enabled();
4391 peerlbl_active = netlbl_active || selinux_xfrm_enabled();
4392 if (!secmark_active && !peerlbl_active)
4393 return NF_ACCEPT;
4394
4395 if (selinux_skb_peerlbl_sid(skb, family, &peer_sid) != 0)
4396 return NF_DROP;
4397
4398 COMMON_AUDIT_DATA_INIT(&ad, NET);
4399 ad.u.net.netif = ifindex;
4400 ad.u.net.family = family;
4401 if (selinux_parse_skb(skb, &ad, &addrp, 1, NULL) != 0)
4402 return NF_DROP;
4403
4404 if (peerlbl_active) {
4405 err = selinux_inet_sys_rcv_skb(ifindex, addrp, family,
4406 peer_sid, &ad);
4407 if (err) {
4408 selinux_netlbl_err(skb, err, 1);
4409 return NF_DROP;
4410 }
4411 }
4412
4413 if (secmark_active)
4414 if (avc_has_perm(peer_sid, skb->secmark,
4415 SECCLASS_PACKET, PACKET__FORWARD_IN, &ad))
4416 return NF_DROP;
4417
4418 if (netlbl_active)
4419 /* we do this in the FORWARD path and not the POST_ROUTING
4420 * path because we want to make sure we apply the necessary
4421 * labeling before IPsec is applied so we can leverage AH
4422 * protection */
4423 if (selinux_netlbl_skbuff_setsid(skb, family, peer_sid) != 0)
4424 return NF_DROP;
4425
4426 return NF_ACCEPT;
4427 }
4428
4429 static unsigned int selinux_ipv4_forward(unsigned int hooknum,
4430 struct sk_buff *skb,
4431 const struct net_device *in,
4432 const struct net_device *out,
4433 int (*okfn)(struct sk_buff *))
4434 {
4435 return selinux_ip_forward(skb, in->ifindex, PF_INET);
4436 }
4437
4438 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
4439 static unsigned int selinux_ipv6_forward(unsigned int hooknum,
4440 struct sk_buff *skb,
4441 const struct net_device *in,
4442 const struct net_device *out,
4443 int (*okfn)(struct sk_buff *))
4444 {
4445 return selinux_ip_forward(skb, in->ifindex, PF_INET6);
4446 }
4447 #endif /* IPV6 */
4448
4449 static unsigned int selinux_ip_output(struct sk_buff *skb,
4450 u16 family)
4451 {
4452 u32 sid;
4453
4454 if (!netlbl_enabled())
4455 return NF_ACCEPT;
4456
4457 /* we do this in the LOCAL_OUT path and not the POST_ROUTING path
4458 * because we want to make sure we apply the necessary labeling
4459 * before IPsec is applied so we can leverage AH protection */
4460 if (skb->sk) {
4461 struct sk_security_struct *sksec = skb->sk->sk_security;
4462 sid = sksec->sid;
4463 } else
4464 sid = SECINITSID_KERNEL;
4465 if (selinux_netlbl_skbuff_setsid(skb, family, sid) != 0)
4466 return NF_DROP;
4467
4468 return NF_ACCEPT;
4469 }
4470
4471 static unsigned int selinux_ipv4_output(unsigned int hooknum,
4472 struct sk_buff *skb,
4473 const struct net_device *in,
4474 const struct net_device *out,
4475 int (*okfn)(struct sk_buff *))
4476 {
4477 return selinux_ip_output(skb, PF_INET);
4478 }
4479
4480 static unsigned int selinux_ip_postroute_compat(struct sk_buff *skb,
4481 int ifindex,
4482 u16 family)
4483 {
4484 struct sock *sk = skb->sk;
4485 struct sk_security_struct *sksec;
4486 struct common_audit_data ad;
4487 char *addrp;
4488 u8 proto;
4489
4490 if (sk == NULL)
4491 return NF_ACCEPT;
4492 sksec = sk->sk_security;
4493
4494 COMMON_AUDIT_DATA_INIT(&ad, NET);
4495 ad.u.net.netif = ifindex;
4496 ad.u.net.family = family;
4497 if (selinux_parse_skb(skb, &ad, &addrp, 0, &proto))
4498 return NF_DROP;
4499
4500 if (selinux_secmark_enabled())
4501 if (avc_has_perm(sksec->sid, skb->secmark,
4502 SECCLASS_PACKET, PACKET__SEND, &ad))
4503 return NF_DROP;
4504
4505 if (selinux_policycap_netpeer)
4506 if (selinux_xfrm_postroute_last(sksec->sid, skb, &ad, proto))
4507 return NF_DROP;
4508
4509 return NF_ACCEPT;
4510 }
4511
4512 static unsigned int selinux_ip_postroute(struct sk_buff *skb, int ifindex,
4513 u16 family)
4514 {
4515 u32 secmark_perm;
4516 u32 peer_sid;
4517 struct sock *sk;
4518 struct common_audit_data ad;
4519 char *addrp;
4520 u8 secmark_active;
4521 u8 peerlbl_active;
4522
4523 /* If any sort of compatibility mode is enabled then handoff processing
4524 * to the selinux_ip_postroute_compat() function to deal with the
4525 * special handling. We do this in an attempt to keep this function
4526 * as fast and as clean as possible. */
4527 if (!selinux_policycap_netpeer)
4528 return selinux_ip_postroute_compat(skb, ifindex, family);
4529 #ifdef CONFIG_XFRM
4530 /* If skb->dst->xfrm is non-NULL then the packet is undergoing an IPsec
4531 * packet transformation so allow the packet to pass without any checks
4532 * since we'll have another chance to perform access control checks
4533 * when the packet is on it's final way out.
4534 * NOTE: there appear to be some IPv6 multicast cases where skb->dst
4535 * is NULL, in this case go ahead and apply access control. */
4536 if (skb_dst(skb) != NULL && skb_dst(skb)->xfrm != NULL)
4537 return NF_ACCEPT;
4538 #endif
4539 secmark_active = selinux_secmark_enabled();
4540 peerlbl_active = netlbl_enabled() || selinux_xfrm_enabled();
4541 if (!secmark_active && !peerlbl_active)
4542 return NF_ACCEPT;
4543
4544 /* if the packet is being forwarded then get the peer label from the
4545 * packet itself; otherwise check to see if it is from a local
4546 * application or the kernel, if from an application get the peer label
4547 * from the sending socket, otherwise use the kernel's sid */
4548 sk = skb->sk;
4549 if (sk == NULL) {
4550 switch (family) {
4551 case PF_INET:
4552 if (IPCB(skb)->flags & IPSKB_FORWARDED)
4553 secmark_perm = PACKET__FORWARD_OUT;
4554 else
4555 secmark_perm = PACKET__SEND;
4556 break;
4557 case PF_INET6:
4558 if (IP6CB(skb)->flags & IP6SKB_FORWARDED)
4559 secmark_perm = PACKET__FORWARD_OUT;
4560 else
4561 secmark_perm = PACKET__SEND;
4562 break;
4563 default:
4564 return NF_DROP;
4565 }
4566 if (secmark_perm == PACKET__FORWARD_OUT) {
4567 if (selinux_skb_peerlbl_sid(skb, family, &peer_sid))
4568 return NF_DROP;
4569 } else
4570 peer_sid = SECINITSID_KERNEL;
4571 } else {
4572 struct sk_security_struct *sksec = sk->sk_security;
4573 peer_sid = sksec->sid;
4574 secmark_perm = PACKET__SEND;
4575 }
4576
4577 COMMON_AUDIT_DATA_INIT(&ad, NET);
4578 ad.u.net.netif = ifindex;
4579 ad.u.net.family = family;
4580 if (selinux_parse_skb(skb, &ad, &addrp, 0, NULL))
4581 return NF_DROP;
4582
4583 if (secmark_active)
4584 if (avc_has_perm(peer_sid, skb->secmark,
4585 SECCLASS_PACKET, secmark_perm, &ad))
4586 return NF_DROP;
4587
4588 if (peerlbl_active) {
4589 u32 if_sid;
4590 u32 node_sid;
4591
4592 if (sel_netif_sid(ifindex, &if_sid))
4593 return NF_DROP;
4594 if (avc_has_perm(peer_sid, if_sid,
4595 SECCLASS_NETIF, NETIF__EGRESS, &ad))
4596 return NF_DROP;
4597
4598 if (sel_netnode_sid(addrp, family, &node_sid))
4599 return NF_DROP;
4600 if (avc_has_perm(peer_sid, node_sid,
4601 SECCLASS_NODE, NODE__SENDTO, &ad))
4602 return NF_DROP;
4603 }
4604
4605 return NF_ACCEPT;
4606 }
4607
4608 static unsigned int selinux_ipv4_postroute(unsigned int hooknum,
4609 struct sk_buff *skb,
4610 const struct net_device *in,
4611 const struct net_device *out,
4612 int (*okfn)(struct sk_buff *))
4613 {
4614 return selinux_ip_postroute(skb, out->ifindex, PF_INET);
4615 }
4616
4617 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
4618 static unsigned int selinux_ipv6_postroute(unsigned int hooknum,
4619 struct sk_buff *skb,
4620 const struct net_device *in,
4621 const struct net_device *out,
4622 int (*okfn)(struct sk_buff *))
4623 {
4624 return selinux_ip_postroute(skb, out->ifindex, PF_INET6);
4625 }
4626 #endif /* IPV6 */
4627
4628 #endif /* CONFIG_NETFILTER */
4629
4630 static int selinux_netlink_send(struct sock *sk, struct sk_buff *skb)
4631 {
4632 int err;
4633
4634 err = cap_netlink_send(sk, skb);
4635 if (err)
4636 return err;
4637
4638 return selinux_nlmsg_perm(sk, skb);
4639 }
4640
4641 static int selinux_netlink_recv(struct sk_buff *skb, int capability)
4642 {
4643 int err;
4644 struct common_audit_data ad;
4645
4646 err = cap_netlink_recv(skb, capability);
4647 if (err)
4648 return err;
4649
4650 COMMON_AUDIT_DATA_INIT(&ad, CAP);
4651 ad.u.cap = capability;
4652
4653 return avc_has_perm(NETLINK_CB(skb).sid, NETLINK_CB(skb).sid,
4654 SECCLASS_CAPABILITY, CAP_TO_MASK(capability), &ad);
4655 }
4656
4657 static int ipc_alloc_security(struct task_struct *task,
4658 struct kern_ipc_perm *perm,
4659 u16 sclass)
4660 {
4661 struct ipc_security_struct *isec;
4662 u32 sid;
4663
4664 isec = kzalloc(sizeof(struct ipc_security_struct), GFP_KERNEL);
4665 if (!isec)
4666 return -ENOMEM;
4667
4668 sid = task_sid(task);
4669 isec->sclass = sclass;
4670 isec->sid = sid;
4671 perm->security = isec;
4672
4673 return 0;
4674 }
4675
4676 static void ipc_free_security(struct kern_ipc_perm *perm)
4677 {
4678 struct ipc_security_struct *isec = perm->security;
4679 perm->security = NULL;
4680 kfree(isec);
4681 }
4682
4683 static int msg_msg_alloc_security(struct msg_msg *msg)
4684 {
4685 struct msg_security_struct *msec;
4686
4687 msec = kzalloc(sizeof(struct msg_security_struct), GFP_KERNEL);
4688 if (!msec)
4689 return -ENOMEM;
4690
4691 msec->sid = SECINITSID_UNLABELED;
4692 msg->security = msec;
4693
4694 return 0;
4695 }
4696
4697 static void msg_msg_free_security(struct msg_msg *msg)
4698 {
4699 struct msg_security_struct *msec = msg->security;
4700
4701 msg->security = NULL;
4702 kfree(msec);
4703 }
4704
4705 static int ipc_has_perm(struct kern_ipc_perm *ipc_perms,
4706 u32 perms)
4707 {
4708 struct ipc_security_struct *isec;
4709 struct common_audit_data ad;
4710 u32 sid = current_sid();
4711
4712 isec = ipc_perms->security;
4713
4714 COMMON_AUDIT_DATA_INIT(&ad, IPC);
4715 ad.u.ipc_id = ipc_perms->key;
4716
4717 return avc_has_perm(sid, isec->sid, isec->sclass, perms, &ad);
4718 }
4719
4720 static int selinux_msg_msg_alloc_security(struct msg_msg *msg)
4721 {
4722 return msg_msg_alloc_security(msg);
4723 }
4724
4725 static void selinux_msg_msg_free_security(struct msg_msg *msg)
4726 {
4727 msg_msg_free_security(msg);
4728 }
4729
4730 /* message queue security operations */
4731 static int selinux_msg_queue_alloc_security(struct msg_queue *msq)
4732 {
4733 struct ipc_security_struct *isec;
4734 struct common_audit_data ad;
4735 u32 sid = current_sid();
4736 int rc;
4737
4738 rc = ipc_alloc_security(current, &msq->q_perm, SECCLASS_MSGQ);
4739 if (rc)
4740 return rc;
4741
4742 isec = msq->q_perm.security;
4743
4744 COMMON_AUDIT_DATA_INIT(&ad, IPC);
4745 ad.u.ipc_id = msq->q_perm.key;
4746
4747 rc = avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
4748 MSGQ__CREATE, &ad);
4749 if (rc) {
4750 ipc_free_security(&msq->q_perm);
4751 return rc;
4752 }
4753 return 0;
4754 }
4755
4756 static void selinux_msg_queue_free_security(struct msg_queue *msq)
4757 {
4758 ipc_free_security(&msq->q_perm);
4759 }
4760
4761 static int selinux_msg_queue_associate(struct msg_queue *msq, int msqflg)
4762 {
4763 struct ipc_security_struct *isec;
4764 struct common_audit_data ad;
4765 u32 sid = current_sid();
4766
4767 isec = msq->q_perm.security;
4768
4769 COMMON_AUDIT_DATA_INIT(&ad, IPC);
4770 ad.u.ipc_id = msq->q_perm.key;
4771
4772 return avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
4773 MSGQ__ASSOCIATE, &ad);
4774 }
4775
4776 static int selinux_msg_queue_msgctl(struct msg_queue *msq, int cmd)
4777 {
4778 int err;
4779 int perms;
4780
4781 switch (cmd) {
4782 case IPC_INFO:
4783 case MSG_INFO:
4784 /* No specific object, just general system-wide information. */
4785 return task_has_system(current, SYSTEM__IPC_INFO);
4786 case IPC_STAT:
4787 case MSG_STAT:
4788 perms = MSGQ__GETATTR | MSGQ__ASSOCIATE;
4789 break;
4790 case IPC_SET:
4791 perms = MSGQ__SETATTR;
4792 break;
4793 case IPC_RMID:
4794 perms = MSGQ__DESTROY;
4795 break;
4796 default:
4797 return 0;
4798 }
4799
4800 err = ipc_has_perm(&msq->q_perm, perms);
4801 return err;
4802 }
4803
4804 static int selinux_msg_queue_msgsnd(struct msg_queue *msq, struct msg_msg *msg, int msqflg)
4805 {
4806 struct ipc_security_struct *isec;
4807 struct msg_security_struct *msec;
4808 struct common_audit_data ad;
4809 u32 sid = current_sid();
4810 int rc;
4811
4812 isec = msq->q_perm.security;
4813 msec = msg->security;
4814
4815 /*
4816 * First time through, need to assign label to the message
4817 */
4818 if (msec->sid == SECINITSID_UNLABELED) {
4819 /*
4820 * Compute new sid based on current process and
4821 * message queue this message will be stored in
4822 */
4823 rc = security_transition_sid(sid, isec->sid, SECCLASS_MSG,
4824 &msec->sid);
4825 if (rc)
4826 return rc;
4827 }
4828
4829 COMMON_AUDIT_DATA_INIT(&ad, IPC);
4830 ad.u.ipc_id = msq->q_perm.key;
4831
4832 /* Can this process write to the queue? */
4833 rc = avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
4834 MSGQ__WRITE, &ad);
4835 if (!rc)
4836 /* Can this process send the message */
4837 rc = avc_has_perm(sid, msec->sid, SECCLASS_MSG,
4838 MSG__SEND, &ad);
4839 if (!rc)
4840 /* Can the message be put in the queue? */
4841 rc = avc_has_perm(msec->sid, isec->sid, SECCLASS_MSGQ,
4842 MSGQ__ENQUEUE, &ad);
4843
4844 return rc;
4845 }
4846
4847 static int selinux_msg_queue_msgrcv(struct msg_queue *msq, struct msg_msg *msg,
4848 struct task_struct *target,
4849 long type, int mode)
4850 {
4851 struct ipc_security_struct *isec;
4852 struct msg_security_struct *msec;
4853 struct common_audit_data ad;
4854 u32 sid = task_sid(target);
4855 int rc;
4856
4857 isec = msq->q_perm.security;
4858 msec = msg->security;
4859
4860 COMMON_AUDIT_DATA_INIT(&ad, IPC);
4861 ad.u.ipc_id = msq->q_perm.key;
4862
4863 rc = avc_has_perm(sid, isec->sid,
4864 SECCLASS_MSGQ, MSGQ__READ, &ad);
4865 if (!rc)
4866 rc = avc_has_perm(sid, msec->sid,
4867 SECCLASS_MSG, MSG__RECEIVE, &ad);
4868 return rc;
4869 }
4870
4871 /* Shared Memory security operations */
4872 static int selinux_shm_alloc_security(struct shmid_kernel *shp)
4873 {
4874 struct ipc_security_struct *isec;
4875 struct common_audit_data ad;
4876 u32 sid = current_sid();
4877 int rc;
4878
4879 rc = ipc_alloc_security(current, &shp->shm_perm, SECCLASS_SHM);
4880 if (rc)
4881 return rc;
4882
4883 isec = shp->shm_perm.security;
4884
4885 COMMON_AUDIT_DATA_INIT(&ad, IPC);
4886 ad.u.ipc_id = shp->shm_perm.key;
4887
4888 rc = avc_has_perm(sid, isec->sid, SECCLASS_SHM,
4889 SHM__CREATE, &ad);
4890 if (rc) {
4891 ipc_free_security(&shp->shm_perm);
4892 return rc;
4893 }
4894 return 0;
4895 }
4896
4897 static void selinux_shm_free_security(struct shmid_kernel *shp)
4898 {
4899 ipc_free_security(&shp->shm_perm);
4900 }
4901
4902 static int selinux_shm_associate(struct shmid_kernel *shp, int shmflg)
4903 {
4904 struct ipc_security_struct *isec;
4905 struct common_audit_data ad;
4906 u32 sid = current_sid();
4907
4908 isec = shp->shm_perm.security;
4909
4910 COMMON_AUDIT_DATA_INIT(&ad, IPC);
4911 ad.u.ipc_id = shp->shm_perm.key;
4912
4913 return avc_has_perm(sid, isec->sid, SECCLASS_SHM,
4914 SHM__ASSOCIATE, &ad);
4915 }
4916
4917 /* Note, at this point, shp is locked down */
4918 static int selinux_shm_shmctl(struct shmid_kernel *shp, int cmd)
4919 {
4920 int perms;
4921 int err;
4922
4923 switch (cmd) {
4924 case IPC_INFO:
4925 case SHM_INFO:
4926 /* No specific object, just general system-wide information. */
4927 return task_has_system(current, SYSTEM__IPC_INFO);
4928 case IPC_STAT:
4929 case SHM_STAT:
4930 perms = SHM__GETATTR | SHM__ASSOCIATE;
4931 break;
4932 case IPC_SET:
4933 perms = SHM__SETATTR;
4934 break;
4935 case SHM_LOCK:
4936 case SHM_UNLOCK:
4937 perms = SHM__LOCK;
4938 break;
4939 case IPC_RMID:
4940 perms = SHM__DESTROY;
4941 break;
4942 default:
4943 return 0;
4944 }
4945
4946 err = ipc_has_perm(&shp->shm_perm, perms);
4947 return err;
4948 }
4949
4950 static int selinux_shm_shmat(struct shmid_kernel *shp,
4951 char __user *shmaddr, int shmflg)
4952 {
4953 u32 perms;
4954
4955 if (shmflg & SHM_RDONLY)
4956 perms = SHM__READ;
4957 else
4958 perms = SHM__READ | SHM__WRITE;
4959
4960 return ipc_has_perm(&shp->shm_perm, perms);
4961 }
4962
4963 /* Semaphore security operations */
4964 static int selinux_sem_alloc_security(struct sem_array *sma)
4965 {
4966 struct ipc_security_struct *isec;
4967 struct common_audit_data ad;
4968 u32 sid = current_sid();
4969 int rc;
4970
4971 rc = ipc_alloc_security(current, &sma->sem_perm, SECCLASS_SEM);
4972 if (rc)
4973 return rc;
4974
4975 isec = sma->sem_perm.security;
4976
4977 COMMON_AUDIT_DATA_INIT(&ad, IPC);
4978 ad.u.ipc_id = sma->sem_perm.key;
4979
4980 rc = avc_has_perm(sid, isec->sid, SECCLASS_SEM,
4981 SEM__CREATE, &ad);
4982 if (rc) {
4983 ipc_free_security(&sma->sem_perm);
4984 return rc;
4985 }
4986 return 0;
4987 }
4988
4989 static void selinux_sem_free_security(struct sem_array *sma)
4990 {
4991 ipc_free_security(&sma->sem_perm);
4992 }
4993
4994 static int selinux_sem_associate(struct sem_array *sma, int semflg)
4995 {
4996 struct ipc_security_struct *isec;
4997 struct common_audit_data ad;
4998 u32 sid = current_sid();
4999
5000 isec = sma->sem_perm.security;
5001
5002 COMMON_AUDIT_DATA_INIT(&ad, IPC);
5003 ad.u.ipc_id = sma->sem_perm.key;
5004
5005 return avc_has_perm(sid, isec->sid, SECCLASS_SEM,
5006 SEM__ASSOCIATE, &ad);
5007 }
5008
5009 /* Note, at this point, sma is locked down */
5010 static int selinux_sem_semctl(struct sem_array *sma, int cmd)
5011 {
5012 int err;
5013 u32 perms;
5014
5015 switch (cmd) {
5016 case IPC_INFO:
5017 case SEM_INFO:
5018 /* No specific object, just general system-wide information. */
5019 return task_has_system(current, SYSTEM__IPC_INFO);
5020 case GETPID:
5021 case GETNCNT:
5022 case GETZCNT:
5023 perms = SEM__GETATTR;
5024 break;
5025 case GETVAL:
5026 case GETALL:
5027 perms = SEM__READ;
5028 break;
5029 case SETVAL:
5030 case SETALL:
5031 perms = SEM__WRITE;
5032 break;
5033 case IPC_RMID:
5034 perms = SEM__DESTROY;
5035 break;
5036 case IPC_SET:
5037 perms = SEM__SETATTR;
5038 break;
5039 case IPC_STAT:
5040 case SEM_STAT:
5041 perms = SEM__GETATTR | SEM__ASSOCIATE;
5042 break;
5043 default:
5044 return 0;
5045 }
5046
5047 err = ipc_has_perm(&sma->sem_perm, perms);
5048 return err;
5049 }
5050
5051 static int selinux_sem_semop(struct sem_array *sma,
5052 struct sembuf *sops, unsigned nsops, int alter)
5053 {
5054 u32 perms;
5055
5056 if (alter)
5057 perms = SEM__READ | SEM__WRITE;
5058 else
5059 perms = SEM__READ;
5060
5061 return ipc_has_perm(&sma->sem_perm, perms);
5062 }
5063
5064 static int selinux_ipc_permission(struct kern_ipc_perm *ipcp, short flag)
5065 {
5066 u32 av = 0;
5067
5068 av = 0;
5069 if (flag & S_IRUGO)
5070 av |= IPC__UNIX_READ;
5071 if (flag & S_IWUGO)
5072 av |= IPC__UNIX_WRITE;
5073
5074 if (av == 0)
5075 return 0;
5076
5077 return ipc_has_perm(ipcp, av);
5078 }
5079
5080 static void selinux_ipc_getsecid(struct kern_ipc_perm *ipcp, u32 *secid)
5081 {
5082 struct ipc_security_struct *isec = ipcp->security;
5083 *secid = isec->sid;
5084 }
5085
5086 static void selinux_d_instantiate(struct dentry *dentry, struct inode *inode)
5087 {
5088 if (inode)
5089 inode_doinit_with_dentry(inode, dentry);
5090 }
5091
5092 static int selinux_getprocattr(struct task_struct *p,
5093 char *name, char **value)
5094 {
5095 const struct task_security_struct *__tsec;
5096 u32 sid;
5097 int error;
5098 unsigned len;
5099
5100 if (current != p) {
5101 error = current_has_perm(p, PROCESS__GETATTR);
5102 if (error)
5103 return error;
5104 }
5105
5106 rcu_read_lock();
5107 __tsec = __task_cred(p)->security;
5108
5109 if (!strcmp(name, "current"))
5110 sid = __tsec->sid;
5111 else if (!strcmp(name, "prev"))
5112 sid = __tsec->osid;
5113 else if (!strcmp(name, "exec"))
5114 sid = __tsec->exec_sid;
5115 else if (!strcmp(name, "fscreate"))
5116 sid = __tsec->create_sid;
5117 else if (!strcmp(name, "keycreate"))
5118 sid = __tsec->keycreate_sid;
5119 else if (!strcmp(name, "sockcreate"))
5120 sid = __tsec->sockcreate_sid;
5121 else
5122 goto invalid;
5123 rcu_read_unlock();
5124
5125 if (!sid)
5126 return 0;
5127
5128 error = security_sid_to_context(sid, value, &len);
5129 if (error)
5130 return error;
5131 return len;
5132
5133 invalid:
5134 rcu_read_unlock();
5135 return -EINVAL;
5136 }
5137
5138 static int selinux_setprocattr(struct task_struct *p,
5139 char *name, void *value, size_t size)
5140 {
5141 struct task_security_struct *tsec;
5142 struct task_struct *tracer;
5143 struct cred *new;
5144 u32 sid = 0, ptsid;
5145 int error;
5146 char *str = value;
5147
5148 if (current != p) {
5149 /* SELinux only allows a process to change its own
5150 security attributes. */
5151 return -EACCES;
5152 }
5153
5154 /*
5155 * Basic control over ability to set these attributes at all.
5156 * current == p, but we'll pass them separately in case the
5157 * above restriction is ever removed.
5158 */
5159 if (!strcmp(name, "exec"))
5160 error = current_has_perm(p, PROCESS__SETEXEC);
5161 else if (!strcmp(name, "fscreate"))
5162 error = current_has_perm(p, PROCESS__SETFSCREATE);
5163 else if (!strcmp(name, "keycreate"))
5164 error = current_has_perm(p, PROCESS__SETKEYCREATE);
5165 else if (!strcmp(name, "sockcreate"))
5166 error = current_has_perm(p, PROCESS__SETSOCKCREATE);
5167 else if (!strcmp(name, "current"))
5168 error = current_has_perm(p, PROCESS__SETCURRENT);
5169 else
5170 error = -EINVAL;
5171 if (error)
5172 return error;
5173
5174 /* Obtain a SID for the context, if one was specified. */
5175 if (size && str[1] && str[1] != '\n') {
5176 if (str[size-1] == '\n') {
5177 str[size-1] = 0;
5178 size--;
5179 }
5180 error = security_context_to_sid(value, size, &sid);
5181 if (error == -EINVAL && !strcmp(name, "fscreate")) {
5182 if (!capable(CAP_MAC_ADMIN))
5183 return error;
5184 error = security_context_to_sid_force(value, size,
5185 &sid);
5186 }
5187 if (error)
5188 return error;
5189 }
5190
5191 new = prepare_creds();
5192 if (!new)
5193 return -ENOMEM;
5194
5195 /* Permission checking based on the specified context is
5196 performed during the actual operation (execve,
5197 open/mkdir/...), when we know the full context of the
5198 operation. See selinux_bprm_set_creds for the execve
5199 checks and may_create for the file creation checks. The
5200 operation will then fail if the context is not permitted. */
5201 tsec = new->security;
5202 if (!strcmp(name, "exec")) {
5203 tsec->exec_sid = sid;
5204 } else if (!strcmp(name, "fscreate")) {
5205 tsec->create_sid = sid;
5206 } else if (!strcmp(name, "keycreate")) {
5207 error = may_create_key(sid, p);
5208 if (error)
5209 goto abort_change;
5210 tsec->keycreate_sid = sid;
5211 } else if (!strcmp(name, "sockcreate")) {
5212 tsec->sockcreate_sid = sid;
5213 } else if (!strcmp(name, "current")) {
5214 error = -EINVAL;
5215 if (sid == 0)
5216 goto abort_change;
5217
5218 /* Only allow single threaded processes to change context */
5219 error = -EPERM;
5220 if (!current_is_single_threaded()) {
5221 error = security_bounded_transition(tsec->sid, sid);
5222 if (error)
5223 goto abort_change;
5224 }
5225
5226 /* Check permissions for the transition. */
5227 error = avc_has_perm(tsec->sid, sid, SECCLASS_PROCESS,
5228 PROCESS__DYNTRANSITION, NULL);
5229 if (error)
5230 goto abort_change;
5231
5232 /* Check for ptracing, and update the task SID if ok.
5233 Otherwise, leave SID unchanged and fail. */
5234 ptsid = 0;
5235 task_lock(p);
5236 tracer = tracehook_tracer_task(p);
5237 if (tracer)
5238 ptsid = task_sid(tracer);
5239 task_unlock(p);
5240
5241 if (tracer) {
5242 error = avc_has_perm(ptsid, sid, SECCLASS_PROCESS,
5243 PROCESS__PTRACE, NULL);
5244 if (error)
5245 goto abort_change;
5246 }
5247
5248 tsec->sid = sid;
5249 } else {
5250 error = -EINVAL;
5251 goto abort_change;
5252 }
5253
5254 commit_creds(new);
5255 return size;
5256
5257 abort_change:
5258 abort_creds(new);
5259 return error;
5260 }
5261
5262 static int selinux_secid_to_secctx(u32 secid, char **secdata, u32 *seclen)
5263 {
5264 return security_sid_to_context(secid, secdata, seclen);
5265 }
5266
5267 static int selinux_secctx_to_secid(const char *secdata, u32 seclen, u32 *secid)
5268 {
5269 return security_context_to_sid(secdata, seclen, secid);
5270 }
5271
5272 static void selinux_release_secctx(char *secdata, u32 seclen)
5273 {
5274 kfree(secdata);
5275 }
5276
5277 /*
5278 * called with inode->i_mutex locked
5279 */
5280 static int selinux_inode_notifysecctx(struct inode *inode, void *ctx, u32 ctxlen)
5281 {
5282 return selinux_inode_setsecurity(inode, XATTR_SELINUX_SUFFIX, ctx, ctxlen, 0);
5283 }
5284
5285 /*
5286 * called with inode->i_mutex locked
5287 */
5288 static int selinux_inode_setsecctx(struct dentry *dentry, void *ctx, u32 ctxlen)
5289 {
5290 return __vfs_setxattr_noperm(dentry, XATTR_NAME_SELINUX, ctx, ctxlen, 0);
5291 }
5292
5293 static int selinux_inode_getsecctx(struct inode *inode, void **ctx, u32 *ctxlen)
5294 {
5295 int len = 0;
5296 len = selinux_inode_getsecurity(inode, XATTR_SELINUX_SUFFIX,
5297 ctx, true);
5298 if (len < 0)
5299 return len;
5300 *ctxlen = len;
5301 return 0;
5302 }
5303 #ifdef CONFIG_KEYS
5304
5305 static int selinux_key_alloc(struct key *k, const struct cred *cred,
5306 unsigned long flags)
5307 {
5308 const struct task_security_struct *tsec;
5309 struct key_security_struct *ksec;
5310
5311 ksec = kzalloc(sizeof(struct key_security_struct), GFP_KERNEL);
5312 if (!ksec)
5313 return -ENOMEM;
5314
5315 tsec = cred->security;
5316 if (tsec->keycreate_sid)
5317 ksec->sid = tsec->keycreate_sid;
5318 else
5319 ksec->sid = tsec->sid;
5320
5321 k->security = ksec;
5322 return 0;
5323 }
5324
5325 static void selinux_key_free(struct key *k)
5326 {
5327 struct key_security_struct *ksec = k->security;
5328
5329 k->security = NULL;
5330 kfree(ksec);
5331 }
5332
5333 static int selinux_key_permission(key_ref_t key_ref,
5334 const struct cred *cred,
5335 key_perm_t perm)
5336 {
5337 struct key *key;
5338 struct key_security_struct *ksec;
5339 u32 sid;
5340
5341 /* if no specific permissions are requested, we skip the
5342 permission check. No serious, additional covert channels
5343 appear to be created. */
5344 if (perm == 0)
5345 return 0;
5346
5347 sid = cred_sid(cred);
5348
5349 key = key_ref_to_ptr(key_ref);
5350 ksec = key->security;
5351
5352 return avc_has_perm(sid, ksec->sid, SECCLASS_KEY, perm, NULL);
5353 }
5354
5355 static int selinux_key_getsecurity(struct key *key, char **_buffer)
5356 {
5357 struct key_security_struct *ksec = key->security;
5358 char *context = NULL;
5359 unsigned len;
5360 int rc;
5361
5362 rc = security_sid_to_context(ksec->sid, &context, &len);
5363 if (!rc)
5364 rc = len;
5365 *_buffer = context;
5366 return rc;
5367 }
5368
5369 #endif
5370
5371 static struct security_operations selinux_ops = {
5372 .name = "selinux",
5373
5374 .ptrace_access_check = selinux_ptrace_access_check,
5375 .ptrace_traceme = selinux_ptrace_traceme,
5376 .capget = selinux_capget,
5377 .capset = selinux_capset,
5378 .sysctl = selinux_sysctl,
5379 .capable = selinux_capable,
5380 .quotactl = selinux_quotactl,
5381 .quota_on = selinux_quota_on,
5382 .syslog = selinux_syslog,
5383 .vm_enough_memory = selinux_vm_enough_memory,
5384
5385 .netlink_send = selinux_netlink_send,
5386 .netlink_recv = selinux_netlink_recv,
5387
5388 .bprm_set_creds = selinux_bprm_set_creds,
5389 .bprm_committing_creds = selinux_bprm_committing_creds,
5390 .bprm_committed_creds = selinux_bprm_committed_creds,
5391 .bprm_secureexec = selinux_bprm_secureexec,
5392
5393 .sb_alloc_security = selinux_sb_alloc_security,
5394 .sb_free_security = selinux_sb_free_security,
5395 .sb_copy_data = selinux_sb_copy_data,
5396 .sb_kern_mount = selinux_sb_kern_mount,
5397 .sb_show_options = selinux_sb_show_options,
5398 .sb_statfs = selinux_sb_statfs,
5399 .sb_mount = selinux_mount,
5400 .sb_umount = selinux_umount,
5401 .sb_set_mnt_opts = selinux_set_mnt_opts,
5402 .sb_clone_mnt_opts = selinux_sb_clone_mnt_opts,
5403 .sb_parse_opts_str = selinux_parse_opts_str,
5404
5405
5406 .inode_alloc_security = selinux_inode_alloc_security,
5407 .inode_free_security = selinux_inode_free_security,
5408 .inode_init_security = selinux_inode_init_security,
5409 .inode_create = selinux_inode_create,
5410 .inode_link = selinux_inode_link,
5411 .inode_unlink = selinux_inode_unlink,
5412 .inode_symlink = selinux_inode_symlink,
5413 .inode_mkdir = selinux_inode_mkdir,
5414 .inode_rmdir = selinux_inode_rmdir,
5415 .inode_mknod = selinux_inode_mknod,
5416 .inode_rename = selinux_inode_rename,
5417 .inode_readlink = selinux_inode_readlink,
5418 .inode_follow_link = selinux_inode_follow_link,
5419 .inode_permission = selinux_inode_permission,
5420 .inode_setattr = selinux_inode_setattr,
5421 .inode_getattr = selinux_inode_getattr,
5422 .inode_setxattr = selinux_inode_setxattr,
5423 .inode_post_setxattr = selinux_inode_post_setxattr,
5424 .inode_getxattr = selinux_inode_getxattr,
5425 .inode_listxattr = selinux_inode_listxattr,
5426 .inode_removexattr = selinux_inode_removexattr,
5427 .inode_getsecurity = selinux_inode_getsecurity,
5428 .inode_setsecurity = selinux_inode_setsecurity,
5429 .inode_listsecurity = selinux_inode_listsecurity,
5430 .inode_getsecid = selinux_inode_getsecid,
5431
5432 .file_permission = selinux_file_permission,
5433 .file_alloc_security = selinux_file_alloc_security,
5434 .file_free_security = selinux_file_free_security,
5435 .file_ioctl = selinux_file_ioctl,
5436 .file_mmap = selinux_file_mmap,
5437 .file_mprotect = selinux_file_mprotect,
5438 .file_lock = selinux_file_lock,
5439 .file_fcntl = selinux_file_fcntl,
5440 .file_set_fowner = selinux_file_set_fowner,
5441 .file_send_sigiotask = selinux_file_send_sigiotask,
5442 .file_receive = selinux_file_receive,
5443
5444 .dentry_open = selinux_dentry_open,
5445
5446 .task_create = selinux_task_create,
5447 .cred_alloc_blank = selinux_cred_alloc_blank,
5448 .cred_free = selinux_cred_free,
5449 .cred_prepare = selinux_cred_prepare,
5450 .cred_transfer = selinux_cred_transfer,
5451 .kernel_act_as = selinux_kernel_act_as,
5452 .kernel_create_files_as = selinux_kernel_create_files_as,
5453 .kernel_module_request = selinux_kernel_module_request,
5454 .task_setpgid = selinux_task_setpgid,
5455 .task_getpgid = selinux_task_getpgid,
5456 .task_getsid = selinux_task_getsid,
5457 .task_getsecid = selinux_task_getsecid,
5458 .task_setnice = selinux_task_setnice,
5459 .task_setioprio = selinux_task_setioprio,
5460 .task_getioprio = selinux_task_getioprio,
5461 .task_setrlimit = selinux_task_setrlimit,
5462 .task_setscheduler = selinux_task_setscheduler,
5463 .task_getscheduler = selinux_task_getscheduler,
5464 .task_movememory = selinux_task_movememory,
5465 .task_kill = selinux_task_kill,
5466 .task_wait = selinux_task_wait,
5467 .task_to_inode = selinux_task_to_inode,
5468
5469 .ipc_permission = selinux_ipc_permission,
5470 .ipc_getsecid = selinux_ipc_getsecid,
5471
5472 .msg_msg_alloc_security = selinux_msg_msg_alloc_security,
5473 .msg_msg_free_security = selinux_msg_msg_free_security,
5474
5475 .msg_queue_alloc_security = selinux_msg_queue_alloc_security,
5476 .msg_queue_free_security = selinux_msg_queue_free_security,
5477 .msg_queue_associate = selinux_msg_queue_associate,
5478 .msg_queue_msgctl = selinux_msg_queue_msgctl,
5479 .msg_queue_msgsnd = selinux_msg_queue_msgsnd,
5480 .msg_queue_msgrcv = selinux_msg_queue_msgrcv,
5481
5482 .shm_alloc_security = selinux_shm_alloc_security,
5483 .shm_free_security = selinux_shm_free_security,
5484 .shm_associate = selinux_shm_associate,
5485 .shm_shmctl = selinux_shm_shmctl,
5486 .shm_shmat = selinux_shm_shmat,
5487
5488 .sem_alloc_security = selinux_sem_alloc_security,
5489 .sem_free_security = selinux_sem_free_security,
5490 .sem_associate = selinux_sem_associate,
5491 .sem_semctl = selinux_sem_semctl,
5492 .sem_semop = selinux_sem_semop,
5493
5494 .d_instantiate = selinux_d_instantiate,
5495
5496 .getprocattr = selinux_getprocattr,
5497 .setprocattr = selinux_setprocattr,
5498
5499 .secid_to_secctx = selinux_secid_to_secctx,
5500 .secctx_to_secid = selinux_secctx_to_secid,
5501 .release_secctx = selinux_release_secctx,
5502 .inode_notifysecctx = selinux_inode_notifysecctx,
5503 .inode_setsecctx = selinux_inode_setsecctx,
5504 .inode_getsecctx = selinux_inode_getsecctx,
5505
5506 .unix_stream_connect = selinux_socket_unix_stream_connect,
5507 .unix_may_send = selinux_socket_unix_may_send,
5508
5509 .socket_create = selinux_socket_create,
5510 .socket_post_create = selinux_socket_post_create,
5511 .socket_bind = selinux_socket_bind,
5512 .socket_connect = selinux_socket_connect,
5513 .socket_listen = selinux_socket_listen,
5514 .socket_accept = selinux_socket_accept,
5515 .socket_sendmsg = selinux_socket_sendmsg,
5516 .socket_recvmsg = selinux_socket_recvmsg,
5517 .socket_getsockname = selinux_socket_getsockname,
5518 .socket_getpeername = selinux_socket_getpeername,
5519 .socket_getsockopt = selinux_socket_getsockopt,
5520 .socket_setsockopt = selinux_socket_setsockopt,
5521 .socket_shutdown = selinux_socket_shutdown,
5522 .socket_sock_rcv_skb = selinux_socket_sock_rcv_skb,
5523 .socket_getpeersec_stream = selinux_socket_getpeersec_stream,
5524 .socket_getpeersec_dgram = selinux_socket_getpeersec_dgram,
5525 .sk_alloc_security = selinux_sk_alloc_security,
5526 .sk_free_security = selinux_sk_free_security,
5527 .sk_clone_security = selinux_sk_clone_security,
5528 .sk_getsecid = selinux_sk_getsecid,
5529 .sock_graft = selinux_sock_graft,
5530 .inet_conn_request = selinux_inet_conn_request,
5531 .inet_csk_clone = selinux_inet_csk_clone,
5532 .inet_conn_established = selinux_inet_conn_established,
5533 .req_classify_flow = selinux_req_classify_flow,
5534 .tun_dev_create = selinux_tun_dev_create,
5535 .tun_dev_post_create = selinux_tun_dev_post_create,
5536 .tun_dev_attach = selinux_tun_dev_attach,
5537
5538 #ifdef CONFIG_SECURITY_NETWORK_XFRM
5539 .xfrm_policy_alloc_security = selinux_xfrm_policy_alloc,
5540 .xfrm_policy_clone_security = selinux_xfrm_policy_clone,
5541 .xfrm_policy_free_security = selinux_xfrm_policy_free,
5542 .xfrm_policy_delete_security = selinux_xfrm_policy_delete,
5543 .xfrm_state_alloc_security = selinux_xfrm_state_alloc,
5544 .xfrm_state_free_security = selinux_xfrm_state_free,
5545 .xfrm_state_delete_security = selinux_xfrm_state_delete,
5546 .xfrm_policy_lookup = selinux_xfrm_policy_lookup,
5547 .xfrm_state_pol_flow_match = selinux_xfrm_state_pol_flow_match,
5548 .xfrm_decode_session = selinux_xfrm_decode_session,
5549 #endif
5550
5551 #ifdef CONFIG_KEYS
5552 .key_alloc = selinux_key_alloc,
5553 .key_free = selinux_key_free,
5554 .key_permission = selinux_key_permission,
5555 .key_getsecurity = selinux_key_getsecurity,
5556 #endif
5557
5558 #ifdef CONFIG_AUDIT
5559 .audit_rule_init = selinux_audit_rule_init,
5560 .audit_rule_known = selinux_audit_rule_known,
5561 .audit_rule_match = selinux_audit_rule_match,
5562 .audit_rule_free = selinux_audit_rule_free,
5563 #endif
5564 };
5565
5566 static __init int selinux_init(void)
5567 {
5568 if (!security_module_enable(&selinux_ops)) {
5569 selinux_enabled = 0;
5570 return 0;
5571 }
5572
5573 if (!selinux_enabled) {
5574 printk(KERN_INFO "SELinux: Disabled at boot.\n");
5575 return 0;
5576 }
5577
5578 printk(KERN_INFO "SELinux: Initializing.\n");
5579
5580 /* Set the security state for the initial task. */
5581 cred_init_security();
5582
5583 default_noexec = !(VM_DATA_DEFAULT_FLAGS & VM_EXEC);
5584
5585 sel_inode_cache = kmem_cache_create("selinux_inode_security",
5586 sizeof(struct inode_security_struct),
5587 0, SLAB_PANIC, NULL);
5588 avc_init();
5589
5590 if (register_security(&selinux_ops))
5591 panic("SELinux: Unable to register with kernel.\n");
5592
5593 if (selinux_enforcing)
5594 printk(KERN_DEBUG "SELinux: Starting in enforcing mode\n");
5595 else
5596 printk(KERN_DEBUG "SELinux: Starting in permissive mode\n");
5597
5598 return 0;
5599 }
5600
5601 static void delayed_superblock_init(struct super_block *sb, void *unused)
5602 {
5603 superblock_doinit(sb, NULL);
5604 }
5605
5606 void selinux_complete_init(void)
5607 {
5608 printk(KERN_DEBUG "SELinux: Completing initialization.\n");
5609
5610 /* Set up any superblocks initialized prior to the policy load. */
5611 printk(KERN_DEBUG "SELinux: Setting up existing superblocks.\n");
5612 iterate_supers(delayed_superblock_init, NULL);
5613 }
5614
5615 /* SELinux requires early initialization in order to label
5616 all processes and objects when they are created. */
5617 security_initcall(selinux_init);
5618
5619 #if defined(CONFIG_NETFILTER)
5620
5621 static struct nf_hook_ops selinux_ipv4_ops[] = {
5622 {
5623 .hook = selinux_ipv4_postroute,
5624 .owner = THIS_MODULE,
5625 .pf = PF_INET,
5626 .hooknum = NF_INET_POST_ROUTING,
5627 .priority = NF_IP_PRI_SELINUX_LAST,
5628 },
5629 {
5630 .hook = selinux_ipv4_forward,
5631 .owner = THIS_MODULE,
5632 .pf = PF_INET,
5633 .hooknum = NF_INET_FORWARD,
5634 .priority = NF_IP_PRI_SELINUX_FIRST,
5635 },
5636 {
5637 .hook = selinux_ipv4_output,
5638 .owner = THIS_MODULE,
5639 .pf = PF_INET,
5640 .hooknum = NF_INET_LOCAL_OUT,
5641 .priority = NF_IP_PRI_SELINUX_FIRST,
5642 }
5643 };
5644
5645 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
5646
5647 static struct nf_hook_ops selinux_ipv6_ops[] = {
5648 {
5649 .hook = selinux_ipv6_postroute,
5650 .owner = THIS_MODULE,
5651 .pf = PF_INET6,
5652 .hooknum = NF_INET_POST_ROUTING,
5653 .priority = NF_IP6_PRI_SELINUX_LAST,
5654 },
5655 {
5656 .hook = selinux_ipv6_forward,
5657 .owner = THIS_MODULE,
5658 .pf = PF_INET6,
5659 .hooknum = NF_INET_FORWARD,
5660 .priority = NF_IP6_PRI_SELINUX_FIRST,
5661 }
5662 };
5663
5664 #endif /* IPV6 */
5665
5666 static int __init selinux_nf_ip_init(void)
5667 {
5668 int err = 0;
5669
5670 if (!selinux_enabled)
5671 goto out;
5672
5673 printk(KERN_DEBUG "SELinux: Registering netfilter hooks\n");
5674
5675 err = nf_register_hooks(selinux_ipv4_ops, ARRAY_SIZE(selinux_ipv4_ops));
5676 if (err)
5677 panic("SELinux: nf_register_hooks for IPv4: error %d\n", err);
5678
5679 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
5680 err = nf_register_hooks(selinux_ipv6_ops, ARRAY_SIZE(selinux_ipv6_ops));
5681 if (err)
5682 panic("SELinux: nf_register_hooks for IPv6: error %d\n", err);
5683 #endif /* IPV6 */
5684
5685 out:
5686 return err;
5687 }
5688
5689 __initcall(selinux_nf_ip_init);
5690
5691 #ifdef CONFIG_SECURITY_SELINUX_DISABLE
5692 static void selinux_nf_ip_exit(void)
5693 {
5694 printk(KERN_DEBUG "SELinux: Unregistering netfilter hooks\n");
5695
5696 nf_unregister_hooks(selinux_ipv4_ops, ARRAY_SIZE(selinux_ipv4_ops));
5697 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
5698 nf_unregister_hooks(selinux_ipv6_ops, ARRAY_SIZE(selinux_ipv6_ops));
5699 #endif /* IPV6 */
5700 }
5701 #endif
5702
5703 #else /* CONFIG_NETFILTER */
5704
5705 #ifdef CONFIG_SECURITY_SELINUX_DISABLE
5706 #define selinux_nf_ip_exit()
5707 #endif
5708
5709 #endif /* CONFIG_NETFILTER */
5710
5711 #ifdef CONFIG_SECURITY_SELINUX_DISABLE
5712 static int selinux_disabled;
5713
5714 int selinux_disable(void)
5715 {
5716 extern void exit_sel_fs(void);
5717
5718 if (ss_initialized) {
5719 /* Not permitted after initial policy load. */
5720 return -EINVAL;
5721 }
5722
5723 if (selinux_disabled) {
5724 /* Only do this once. */
5725 return -EINVAL;
5726 }
5727
5728 printk(KERN_INFO "SELinux: Disabled at runtime.\n");
5729
5730 selinux_disabled = 1;
5731 selinux_enabled = 0;
5732
5733 reset_security_ops();
5734
5735 /* Try to destroy the avc node cache */
5736 avc_disable();
5737
5738 /* Unregister netfilter hooks. */
5739 selinux_nf_ip_exit();
5740
5741 /* Unregister selinuxfs. */
5742 exit_sel_fs();
5743
5744 return 0;
5745 }
5746 #endif
Linux kernel - Deliverables
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