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[mirror_ubuntu-artful-kernel.git] / security / selinux / hooks.c
1 /*
2 * NSA Security-Enhanced Linux (SELinux) security module
3 *
4 * This file contains the SELinux hook function implementations.
5 *
6 * Authors: Stephen Smalley, <sds@epoch.ncsc.mil>
7 * Chris Vance, <cvance@nai.com>
8 * Wayne Salamon, <wsalamon@nai.com>
9 * James Morris <jmorris@redhat.com>
10 *
11 * Copyright (C) 2001,2002 Networks Associates Technology, Inc.
12 * Copyright (C) 2003-2008 Red Hat, Inc., James Morris <jmorris@redhat.com>
13 * Eric Paris <eparis@redhat.com>
14 * Copyright (C) 2004-2005 Trusted Computer Solutions, Inc.
15 * <dgoeddel@trustedcs.com>
16 * Copyright (C) 2006, 2007, 2009 Hewlett-Packard Development Company, L.P.
17 * Paul Moore <paul.moore@hp.com>
18 * Copyright (C) 2007 Hitachi Software Engineering Co., Ltd.
19 * Yuichi Nakamura <ynakam@hitachisoft.jp>
20 *
21 * This program is free software; you can redistribute it and/or modify
22 * it under the terms of the GNU General Public License version 2,
23 * as published by the Free Software Foundation.
24 */
25
26 #include <linux/init.h>
27 #include <linux/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 mode_t mode = file->f_path.dentry->d_inode->i_mode;
1781 /*
1782 * lnk files and socks do not really have an 'open'
1783 */
1784 if (S_ISREG(mode))
1785 av |= FILE__OPEN;
1786 else if (S_ISCHR(mode))
1787 av |= CHR_FILE__OPEN;
1788 else if (S_ISBLK(mode))
1789 av |= BLK_FILE__OPEN;
1790 else if (S_ISFIFO(mode))
1791 av |= FIFO_FILE__OPEN;
1792 else if (S_ISDIR(mode))
1793 av |= DIR__OPEN;
1794 else if (S_ISSOCK(mode))
1795 av |= SOCK_FILE__OPEN;
1796 else
1797 printk(KERN_ERR "SELinux: WARNING: inside %s with "
1798 "unknown mode:%o\n", __func__, mode);
1799 }
1800 return av;
1801 }
1802
1803 /* Hook functions begin here. */
1804
1805 static int selinux_ptrace_access_check(struct task_struct *child,
1806 unsigned int mode)
1807 {
1808 int rc;
1809
1810 rc = cap_ptrace_access_check(child, mode);
1811 if (rc)
1812 return rc;
1813
1814 if (mode == PTRACE_MODE_READ) {
1815 u32 sid = current_sid();
1816 u32 csid = task_sid(child);
1817 return avc_has_perm(sid, csid, SECCLASS_FILE, FILE__READ, NULL);
1818 }
1819
1820 return current_has_perm(child, PROCESS__PTRACE);
1821 }
1822
1823 static int selinux_ptrace_traceme(struct task_struct *parent)
1824 {
1825 int rc;
1826
1827 rc = cap_ptrace_traceme(parent);
1828 if (rc)
1829 return rc;
1830
1831 return task_has_perm(parent, current, PROCESS__PTRACE);
1832 }
1833
1834 static int selinux_capget(struct task_struct *target, kernel_cap_t *effective,
1835 kernel_cap_t *inheritable, kernel_cap_t *permitted)
1836 {
1837 int error;
1838
1839 error = current_has_perm(target, PROCESS__GETCAP);
1840 if (error)
1841 return error;
1842
1843 return cap_capget(target, effective, inheritable, permitted);
1844 }
1845
1846 static int selinux_capset(struct cred *new, const struct cred *old,
1847 const kernel_cap_t *effective,
1848 const kernel_cap_t *inheritable,
1849 const kernel_cap_t *permitted)
1850 {
1851 int error;
1852
1853 error = cap_capset(new, old,
1854 effective, inheritable, permitted);
1855 if (error)
1856 return error;
1857
1858 return cred_has_perm(old, new, PROCESS__SETCAP);
1859 }
1860
1861 /*
1862 * (This comment used to live with the selinux_task_setuid hook,
1863 * which was removed).
1864 *
1865 * Since setuid only affects the current process, and since the SELinux
1866 * controls are not based on the Linux identity attributes, SELinux does not
1867 * need to control this operation. However, SELinux does control the use of
1868 * the CAP_SETUID and CAP_SETGID capabilities using the capable hook.
1869 */
1870
1871 static int selinux_capable(struct task_struct *tsk, const struct cred *cred,
1872 int cap, int audit)
1873 {
1874 int rc;
1875
1876 rc = cap_capable(tsk, cred, cap, audit);
1877 if (rc)
1878 return rc;
1879
1880 return task_has_capability(tsk, cred, cap, audit);
1881 }
1882
1883 static int selinux_sysctl_get_sid(ctl_table *table, u16 tclass, u32 *sid)
1884 {
1885 int buflen, rc;
1886 char *buffer, *path, *end;
1887
1888 rc = -ENOMEM;
1889 buffer = (char *)__get_free_page(GFP_KERNEL);
1890 if (!buffer)
1891 goto out;
1892
1893 buflen = PAGE_SIZE;
1894 end = buffer+buflen;
1895 *--end = '\0';
1896 buflen--;
1897 path = end-1;
1898 *path = '/';
1899 while (table) {
1900 const char *name = table->procname;
1901 size_t namelen = strlen(name);
1902 buflen -= namelen + 1;
1903 if (buflen < 0)
1904 goto out_free;
1905 end -= namelen;
1906 memcpy(end, name, namelen);
1907 *--end = '/';
1908 path = end;
1909 table = table->parent;
1910 }
1911 buflen -= 4;
1912 if (buflen < 0)
1913 goto out_free;
1914 end -= 4;
1915 memcpy(end, "/sys", 4);
1916 path = end;
1917 rc = security_genfs_sid("proc", path, tclass, sid);
1918 out_free:
1919 free_page((unsigned long)buffer);
1920 out:
1921 return rc;
1922 }
1923
1924 static int selinux_sysctl(ctl_table *table, int op)
1925 {
1926 int error = 0;
1927 u32 av;
1928 u32 tsid, sid;
1929 int rc;
1930
1931 sid = current_sid();
1932
1933 rc = selinux_sysctl_get_sid(table, (op == 0001) ?
1934 SECCLASS_DIR : SECCLASS_FILE, &tsid);
1935 if (rc) {
1936 /* Default to the well-defined sysctl SID. */
1937 tsid = SECINITSID_SYSCTL;
1938 }
1939
1940 /* The op values are "defined" in sysctl.c, thereby creating
1941 * a bad coupling between this module and sysctl.c */
1942 if (op == 001) {
1943 error = avc_has_perm(sid, tsid,
1944 SECCLASS_DIR, DIR__SEARCH, NULL);
1945 } else {
1946 av = 0;
1947 if (op & 004)
1948 av |= FILE__READ;
1949 if (op & 002)
1950 av |= FILE__WRITE;
1951 if (av)
1952 error = avc_has_perm(sid, tsid,
1953 SECCLASS_FILE, av, NULL);
1954 }
1955
1956 return error;
1957 }
1958
1959 static int selinux_quotactl(int cmds, int type, int id, struct super_block *sb)
1960 {
1961 const struct cred *cred = current_cred();
1962 int rc = 0;
1963
1964 if (!sb)
1965 return 0;
1966
1967 switch (cmds) {
1968 case Q_SYNC:
1969 case Q_QUOTAON:
1970 case Q_QUOTAOFF:
1971 case Q_SETINFO:
1972 case Q_SETQUOTA:
1973 rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAMOD, NULL);
1974 break;
1975 case Q_GETFMT:
1976 case Q_GETINFO:
1977 case Q_GETQUOTA:
1978 rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAGET, NULL);
1979 break;
1980 default:
1981 rc = 0; /* let the kernel handle invalid cmds */
1982 break;
1983 }
1984 return rc;
1985 }
1986
1987 static int selinux_quota_on(struct dentry *dentry)
1988 {
1989 const struct cred *cred = current_cred();
1990
1991 return dentry_has_perm(cred, NULL, dentry, FILE__QUOTAON);
1992 }
1993
1994 static int selinux_syslog(int type, bool from_file)
1995 {
1996 int rc;
1997
1998 rc = cap_syslog(type, from_file);
1999 if (rc)
2000 return rc;
2001
2002 switch (type) {
2003 case SYSLOG_ACTION_READ_ALL: /* Read last kernel messages */
2004 case SYSLOG_ACTION_SIZE_BUFFER: /* Return size of the log buffer */
2005 rc = task_has_system(current, SYSTEM__SYSLOG_READ);
2006 break;
2007 case SYSLOG_ACTION_CONSOLE_OFF: /* Disable logging to console */
2008 case SYSLOG_ACTION_CONSOLE_ON: /* Enable logging to console */
2009 /* Set level of messages printed to console */
2010 case SYSLOG_ACTION_CONSOLE_LEVEL:
2011 rc = task_has_system(current, SYSTEM__SYSLOG_CONSOLE);
2012 break;
2013 case SYSLOG_ACTION_CLOSE: /* Close log */
2014 case SYSLOG_ACTION_OPEN: /* Open log */
2015 case SYSLOG_ACTION_READ: /* Read from log */
2016 case SYSLOG_ACTION_READ_CLEAR: /* Read/clear last kernel messages */
2017 case SYSLOG_ACTION_CLEAR: /* Clear ring buffer */
2018 default:
2019 rc = task_has_system(current, SYSTEM__SYSLOG_MOD);
2020 break;
2021 }
2022 return rc;
2023 }
2024
2025 /*
2026 * Check that a process has enough memory to allocate a new virtual
2027 * mapping. 0 means there is enough memory for the allocation to
2028 * succeed and -ENOMEM implies there is not.
2029 *
2030 * Do not audit the selinux permission check, as this is applied to all
2031 * processes that allocate mappings.
2032 */
2033 static int selinux_vm_enough_memory(struct mm_struct *mm, long pages)
2034 {
2035 int rc, cap_sys_admin = 0;
2036
2037 rc = selinux_capable(current, current_cred(), CAP_SYS_ADMIN,
2038 SECURITY_CAP_NOAUDIT);
2039 if (rc == 0)
2040 cap_sys_admin = 1;
2041
2042 return __vm_enough_memory(mm, pages, cap_sys_admin);
2043 }
2044
2045 /* binprm security operations */
2046
2047 static int selinux_bprm_set_creds(struct linux_binprm *bprm)
2048 {
2049 const struct task_security_struct *old_tsec;
2050 struct task_security_struct *new_tsec;
2051 struct inode_security_struct *isec;
2052 struct common_audit_data ad;
2053 struct inode *inode = bprm->file->f_path.dentry->d_inode;
2054 int rc;
2055
2056 rc = cap_bprm_set_creds(bprm);
2057 if (rc)
2058 return rc;
2059
2060 /* SELinux context only depends on initial program or script and not
2061 * the script interpreter */
2062 if (bprm->cred_prepared)
2063 return 0;
2064
2065 old_tsec = current_security();
2066 new_tsec = bprm->cred->security;
2067 isec = inode->i_security;
2068
2069 /* Default to the current task SID. */
2070 new_tsec->sid = old_tsec->sid;
2071 new_tsec->osid = old_tsec->sid;
2072
2073 /* Reset fs, key, and sock SIDs on execve. */
2074 new_tsec->create_sid = 0;
2075 new_tsec->keycreate_sid = 0;
2076 new_tsec->sockcreate_sid = 0;
2077
2078 if (old_tsec->exec_sid) {
2079 new_tsec->sid = old_tsec->exec_sid;
2080 /* Reset exec SID on execve. */
2081 new_tsec->exec_sid = 0;
2082 } else {
2083 /* Check for a default transition on this program. */
2084 rc = security_transition_sid(old_tsec->sid, isec->sid,
2085 SECCLASS_PROCESS, &new_tsec->sid);
2086 if (rc)
2087 return rc;
2088 }
2089
2090 COMMON_AUDIT_DATA_INIT(&ad, FS);
2091 ad.u.fs.path = bprm->file->f_path;
2092
2093 if (bprm->file->f_path.mnt->mnt_flags & MNT_NOSUID)
2094 new_tsec->sid = old_tsec->sid;
2095
2096 if (new_tsec->sid == old_tsec->sid) {
2097 rc = avc_has_perm(old_tsec->sid, isec->sid,
2098 SECCLASS_FILE, FILE__EXECUTE_NO_TRANS, &ad);
2099 if (rc)
2100 return rc;
2101 } else {
2102 /* Check permissions for the transition. */
2103 rc = avc_has_perm(old_tsec->sid, new_tsec->sid,
2104 SECCLASS_PROCESS, PROCESS__TRANSITION, &ad);
2105 if (rc)
2106 return rc;
2107
2108 rc = avc_has_perm(new_tsec->sid, isec->sid,
2109 SECCLASS_FILE, FILE__ENTRYPOINT, &ad);
2110 if (rc)
2111 return rc;
2112
2113 /* Check for shared state */
2114 if (bprm->unsafe & LSM_UNSAFE_SHARE) {
2115 rc = avc_has_perm(old_tsec->sid, new_tsec->sid,
2116 SECCLASS_PROCESS, PROCESS__SHARE,
2117 NULL);
2118 if (rc)
2119 return -EPERM;
2120 }
2121
2122 /* Make sure that anyone attempting to ptrace over a task that
2123 * changes its SID has the appropriate permit */
2124 if (bprm->unsafe &
2125 (LSM_UNSAFE_PTRACE | LSM_UNSAFE_PTRACE_CAP)) {
2126 struct task_struct *tracer;
2127 struct task_security_struct *sec;
2128 u32 ptsid = 0;
2129
2130 rcu_read_lock();
2131 tracer = tracehook_tracer_task(current);
2132 if (likely(tracer != NULL)) {
2133 sec = __task_cred(tracer)->security;
2134 ptsid = sec->sid;
2135 }
2136 rcu_read_unlock();
2137
2138 if (ptsid != 0) {
2139 rc = avc_has_perm(ptsid, new_tsec->sid,
2140 SECCLASS_PROCESS,
2141 PROCESS__PTRACE, NULL);
2142 if (rc)
2143 return -EPERM;
2144 }
2145 }
2146
2147 /* Clear any possibly unsafe personality bits on exec: */
2148 bprm->per_clear |= PER_CLEAR_ON_SETID;
2149 }
2150
2151 return 0;
2152 }
2153
2154 static int selinux_bprm_secureexec(struct linux_binprm *bprm)
2155 {
2156 const struct task_security_struct *tsec = current_security();
2157 u32 sid, osid;
2158 int atsecure = 0;
2159
2160 sid = tsec->sid;
2161 osid = tsec->osid;
2162
2163 if (osid != sid) {
2164 /* Enable secure mode for SIDs transitions unless
2165 the noatsecure permission is granted between
2166 the two SIDs, i.e. ahp returns 0. */
2167 atsecure = avc_has_perm(osid, sid,
2168 SECCLASS_PROCESS,
2169 PROCESS__NOATSECURE, NULL);
2170 }
2171
2172 return (atsecure || cap_bprm_secureexec(bprm));
2173 }
2174
2175 extern struct vfsmount *selinuxfs_mount;
2176 extern struct dentry *selinux_null;
2177
2178 /* Derived from fs/exec.c:flush_old_files. */
2179 static inline void flush_unauthorized_files(const struct cred *cred,
2180 struct files_struct *files)
2181 {
2182 struct common_audit_data ad;
2183 struct file *file, *devnull = NULL;
2184 struct tty_struct *tty;
2185 struct fdtable *fdt;
2186 long j = -1;
2187 int drop_tty = 0;
2188
2189 tty = get_current_tty();
2190 if (tty) {
2191 file_list_lock();
2192 if (!list_empty(&tty->tty_files)) {
2193 struct inode *inode;
2194
2195 /* Revalidate access to controlling tty.
2196 Use inode_has_perm on the tty inode directly rather
2197 than using file_has_perm, as this particular open
2198 file may belong to another process and we are only
2199 interested in the inode-based check here. */
2200 file = list_first_entry(&tty->tty_files, struct file, f_u.fu_list);
2201 inode = file->f_path.dentry->d_inode;
2202 if (inode_has_perm(cred, inode,
2203 FILE__READ | FILE__WRITE, NULL)) {
2204 drop_tty = 1;
2205 }
2206 }
2207 file_list_unlock();
2208 tty_kref_put(tty);
2209 }
2210 /* Reset controlling tty. */
2211 if (drop_tty)
2212 no_tty();
2213
2214 /* Revalidate access to inherited open files. */
2215
2216 COMMON_AUDIT_DATA_INIT(&ad, FS);
2217
2218 spin_lock(&files->file_lock);
2219 for (;;) {
2220 unsigned long set, i;
2221 int fd;
2222
2223 j++;
2224 i = j * __NFDBITS;
2225 fdt = files_fdtable(files);
2226 if (i >= fdt->max_fds)
2227 break;
2228 set = fdt->open_fds->fds_bits[j];
2229 if (!set)
2230 continue;
2231 spin_unlock(&files->file_lock);
2232 for ( ; set ; i++, set >>= 1) {
2233 if (set & 1) {
2234 file = fget(i);
2235 if (!file)
2236 continue;
2237 if (file_has_perm(cred,
2238 file,
2239 file_to_av(file))) {
2240 sys_close(i);
2241 fd = get_unused_fd();
2242 if (fd != i) {
2243 if (fd >= 0)
2244 put_unused_fd(fd);
2245 fput(file);
2246 continue;
2247 }
2248 if (devnull) {
2249 get_file(devnull);
2250 } else {
2251 devnull = dentry_open(
2252 dget(selinux_null),
2253 mntget(selinuxfs_mount),
2254 O_RDWR, cred);
2255 if (IS_ERR(devnull)) {
2256 devnull = NULL;
2257 put_unused_fd(fd);
2258 fput(file);
2259 continue;
2260 }
2261 }
2262 fd_install(fd, devnull);
2263 }
2264 fput(file);
2265 }
2266 }
2267 spin_lock(&files->file_lock);
2268
2269 }
2270 spin_unlock(&files->file_lock);
2271 }
2272
2273 /*
2274 * Prepare a process for imminent new credential changes due to exec
2275 */
2276 static void selinux_bprm_committing_creds(struct linux_binprm *bprm)
2277 {
2278 struct task_security_struct *new_tsec;
2279 struct rlimit *rlim, *initrlim;
2280 int rc, i;
2281
2282 new_tsec = bprm->cred->security;
2283 if (new_tsec->sid == new_tsec->osid)
2284 return;
2285
2286 /* Close files for which the new task SID is not authorized. */
2287 flush_unauthorized_files(bprm->cred, current->files);
2288
2289 /* Always clear parent death signal on SID transitions. */
2290 current->pdeath_signal = 0;
2291
2292 /* Check whether the new SID can inherit resource limits from the old
2293 * SID. If not, reset all soft limits to the lower of the current
2294 * task's hard limit and the init task's soft limit.
2295 *
2296 * Note that the setting of hard limits (even to lower them) can be
2297 * controlled by the setrlimit check. The inclusion of the init task's
2298 * soft limit into the computation is to avoid resetting soft limits
2299 * higher than the default soft limit for cases where the default is
2300 * lower than the hard limit, e.g. RLIMIT_CORE or RLIMIT_STACK.
2301 */
2302 rc = avc_has_perm(new_tsec->osid, new_tsec->sid, SECCLASS_PROCESS,
2303 PROCESS__RLIMITINH, NULL);
2304 if (rc) {
2305 for (i = 0; i < RLIM_NLIMITS; i++) {
2306 rlim = current->signal->rlim + i;
2307 initrlim = init_task.signal->rlim + i;
2308 rlim->rlim_cur = min(rlim->rlim_max, initrlim->rlim_cur);
2309 }
2310 update_rlimit_cpu(current->signal->rlim[RLIMIT_CPU].rlim_cur);
2311 }
2312 }
2313
2314 /*
2315 * Clean up the process immediately after the installation of new credentials
2316 * due to exec
2317 */
2318 static void selinux_bprm_committed_creds(struct linux_binprm *bprm)
2319 {
2320 const struct task_security_struct *tsec = current_security();
2321 struct itimerval itimer;
2322 u32 osid, sid;
2323 int rc, i;
2324
2325 osid = tsec->osid;
2326 sid = tsec->sid;
2327
2328 if (sid == osid)
2329 return;
2330
2331 /* Check whether the new SID can inherit signal state from the old SID.
2332 * If not, clear itimers to avoid subsequent signal generation and
2333 * flush and unblock signals.
2334 *
2335 * This must occur _after_ the task SID has been updated so that any
2336 * kill done after the flush will be checked against the new SID.
2337 */
2338 rc = avc_has_perm(osid, sid, SECCLASS_PROCESS, PROCESS__SIGINH, NULL);
2339 if (rc) {
2340 memset(&itimer, 0, sizeof itimer);
2341 for (i = 0; i < 3; i++)
2342 do_setitimer(i, &itimer, NULL);
2343 spin_lock_irq(&current->sighand->siglock);
2344 if (!(current->signal->flags & SIGNAL_GROUP_EXIT)) {
2345 __flush_signals(current);
2346 flush_signal_handlers(current, 1);
2347 sigemptyset(&current->blocked);
2348 }
2349 spin_unlock_irq(&current->sighand->siglock);
2350 }
2351
2352 /* Wake up the parent if it is waiting so that it can recheck
2353 * wait permission to the new task SID. */
2354 read_lock(&tasklist_lock);
2355 __wake_up_parent(current, current->real_parent);
2356 read_unlock(&tasklist_lock);
2357 }
2358
2359 /* superblock security operations */
2360
2361 static int selinux_sb_alloc_security(struct super_block *sb)
2362 {
2363 return superblock_alloc_security(sb);
2364 }
2365
2366 static void selinux_sb_free_security(struct super_block *sb)
2367 {
2368 superblock_free_security(sb);
2369 }
2370
2371 static inline int match_prefix(char *prefix, int plen, char *option, int olen)
2372 {
2373 if (plen > olen)
2374 return 0;
2375
2376 return !memcmp(prefix, option, plen);
2377 }
2378
2379 static inline int selinux_option(char *option, int len)
2380 {
2381 return (match_prefix(CONTEXT_STR, sizeof(CONTEXT_STR)-1, option, len) ||
2382 match_prefix(FSCONTEXT_STR, sizeof(FSCONTEXT_STR)-1, option, len) ||
2383 match_prefix(DEFCONTEXT_STR, sizeof(DEFCONTEXT_STR)-1, option, len) ||
2384 match_prefix(ROOTCONTEXT_STR, sizeof(ROOTCONTEXT_STR)-1, option, len) ||
2385 match_prefix(LABELSUPP_STR, sizeof(LABELSUPP_STR)-1, option, len));
2386 }
2387
2388 static inline void take_option(char **to, char *from, int *first, int len)
2389 {
2390 if (!*first) {
2391 **to = ',';
2392 *to += 1;
2393 } else
2394 *first = 0;
2395 memcpy(*to, from, len);
2396 *to += len;
2397 }
2398
2399 static inline void take_selinux_option(char **to, char *from, int *first,
2400 int len)
2401 {
2402 int current_size = 0;
2403
2404 if (!*first) {
2405 **to = '|';
2406 *to += 1;
2407 } else
2408 *first = 0;
2409
2410 while (current_size < len) {
2411 if (*from != '"') {
2412 **to = *from;
2413 *to += 1;
2414 }
2415 from += 1;
2416 current_size += 1;
2417 }
2418 }
2419
2420 static int selinux_sb_copy_data(char *orig, char *copy)
2421 {
2422 int fnosec, fsec, rc = 0;
2423 char *in_save, *in_curr, *in_end;
2424 char *sec_curr, *nosec_save, *nosec;
2425 int open_quote = 0;
2426
2427 in_curr = orig;
2428 sec_curr = copy;
2429
2430 nosec = (char *)get_zeroed_page(GFP_KERNEL);
2431 if (!nosec) {
2432 rc = -ENOMEM;
2433 goto out;
2434 }
2435
2436 nosec_save = nosec;
2437 fnosec = fsec = 1;
2438 in_save = in_end = orig;
2439
2440 do {
2441 if (*in_end == '"')
2442 open_quote = !open_quote;
2443 if ((*in_end == ',' && open_quote == 0) ||
2444 *in_end == '\0') {
2445 int len = in_end - in_curr;
2446
2447 if (selinux_option(in_curr, len))
2448 take_selinux_option(&sec_curr, in_curr, &fsec, len);
2449 else
2450 take_option(&nosec, in_curr, &fnosec, len);
2451
2452 in_curr = in_end + 1;
2453 }
2454 } while (*in_end++);
2455
2456 strcpy(in_save, nosec_save);
2457 free_page((unsigned long)nosec_save);
2458 out:
2459 return rc;
2460 }
2461
2462 static int selinux_sb_kern_mount(struct super_block *sb, int flags, void *data)
2463 {
2464 const struct cred *cred = current_cred();
2465 struct common_audit_data ad;
2466 int rc;
2467
2468 rc = superblock_doinit(sb, data);
2469 if (rc)
2470 return rc;
2471
2472 /* Allow all mounts performed by the kernel */
2473 if (flags & MS_KERNMOUNT)
2474 return 0;
2475
2476 COMMON_AUDIT_DATA_INIT(&ad, FS);
2477 ad.u.fs.path.dentry = sb->s_root;
2478 return superblock_has_perm(cred, sb, FILESYSTEM__MOUNT, &ad);
2479 }
2480
2481 static int selinux_sb_statfs(struct dentry *dentry)
2482 {
2483 const struct cred *cred = current_cred();
2484 struct common_audit_data ad;
2485
2486 COMMON_AUDIT_DATA_INIT(&ad, FS);
2487 ad.u.fs.path.dentry = dentry->d_sb->s_root;
2488 return superblock_has_perm(cred, dentry->d_sb, FILESYSTEM__GETATTR, &ad);
2489 }
2490
2491 static int selinux_mount(char *dev_name,
2492 struct path *path,
2493 char *type,
2494 unsigned long flags,
2495 void *data)
2496 {
2497 const struct cred *cred = current_cred();
2498
2499 if (flags & MS_REMOUNT)
2500 return superblock_has_perm(cred, path->mnt->mnt_sb,
2501 FILESYSTEM__REMOUNT, NULL);
2502 else
2503 return dentry_has_perm(cred, path->mnt, path->dentry,
2504 FILE__MOUNTON);
2505 }
2506
2507 static int selinux_umount(struct vfsmount *mnt, int flags)
2508 {
2509 const struct cred *cred = current_cred();
2510
2511 return superblock_has_perm(cred, mnt->mnt_sb,
2512 FILESYSTEM__UNMOUNT, NULL);
2513 }
2514
2515 /* inode security operations */
2516
2517 static int selinux_inode_alloc_security(struct inode *inode)
2518 {
2519 return inode_alloc_security(inode);
2520 }
2521
2522 static void selinux_inode_free_security(struct inode *inode)
2523 {
2524 inode_free_security(inode);
2525 }
2526
2527 static int selinux_inode_init_security(struct inode *inode, struct inode *dir,
2528 char **name, void **value,
2529 size_t *len)
2530 {
2531 const struct task_security_struct *tsec = current_security();
2532 struct inode_security_struct *dsec;
2533 struct superblock_security_struct *sbsec;
2534 u32 sid, newsid, clen;
2535 int rc;
2536 char *namep = NULL, *context;
2537
2538 dsec = dir->i_security;
2539 sbsec = dir->i_sb->s_security;
2540
2541 sid = tsec->sid;
2542 newsid = tsec->create_sid;
2543
2544 if (!newsid || !(sbsec->flags & SE_SBLABELSUPP)) {
2545 rc = security_transition_sid(sid, dsec->sid,
2546 inode_mode_to_security_class(inode->i_mode),
2547 &newsid);
2548 if (rc) {
2549 printk(KERN_WARNING "%s: "
2550 "security_transition_sid failed, rc=%d (dev=%s "
2551 "ino=%ld)\n",
2552 __func__,
2553 -rc, inode->i_sb->s_id, inode->i_ino);
2554 return rc;
2555 }
2556 }
2557
2558 /* Possibly defer initialization to selinux_complete_init. */
2559 if (sbsec->flags & SE_SBINITIALIZED) {
2560 struct inode_security_struct *isec = inode->i_security;
2561 isec->sclass = inode_mode_to_security_class(inode->i_mode);
2562 isec->sid = newsid;
2563 isec->initialized = 1;
2564 }
2565
2566 if (!ss_initialized || !(sbsec->flags & SE_SBLABELSUPP))
2567 return -EOPNOTSUPP;
2568
2569 if (name) {
2570 namep = kstrdup(XATTR_SELINUX_SUFFIX, GFP_NOFS);
2571 if (!namep)
2572 return -ENOMEM;
2573 *name = namep;
2574 }
2575
2576 if (value && len) {
2577 rc = security_sid_to_context_force(newsid, &context, &clen);
2578 if (rc) {
2579 kfree(namep);
2580 return rc;
2581 }
2582 *value = context;
2583 *len = clen;
2584 }
2585
2586 return 0;
2587 }
2588
2589 static int selinux_inode_create(struct inode *dir, struct dentry *dentry, int mask)
2590 {
2591 return may_create(dir, dentry, SECCLASS_FILE);
2592 }
2593
2594 static int selinux_inode_link(struct dentry *old_dentry, struct inode *dir, struct dentry *new_dentry)
2595 {
2596 return may_link(dir, old_dentry, MAY_LINK);
2597 }
2598
2599 static int selinux_inode_unlink(struct inode *dir, struct dentry *dentry)
2600 {
2601 return may_link(dir, dentry, MAY_UNLINK);
2602 }
2603
2604 static int selinux_inode_symlink(struct inode *dir, struct dentry *dentry, const char *name)
2605 {
2606 return may_create(dir, dentry, SECCLASS_LNK_FILE);
2607 }
2608
2609 static int selinux_inode_mkdir(struct inode *dir, struct dentry *dentry, int mask)
2610 {
2611 return may_create(dir, dentry, SECCLASS_DIR);
2612 }
2613
2614 static int selinux_inode_rmdir(struct inode *dir, struct dentry *dentry)
2615 {
2616 return may_link(dir, dentry, MAY_RMDIR);
2617 }
2618
2619 static int selinux_inode_mknod(struct inode *dir, struct dentry *dentry, int mode, dev_t dev)
2620 {
2621 return may_create(dir, dentry, inode_mode_to_security_class(mode));
2622 }
2623
2624 static int selinux_inode_rename(struct inode *old_inode, struct dentry *old_dentry,
2625 struct inode *new_inode, struct dentry *new_dentry)
2626 {
2627 return may_rename(old_inode, old_dentry, new_inode, new_dentry);
2628 }
2629
2630 static int selinux_inode_readlink(struct dentry *dentry)
2631 {
2632 const struct cred *cred = current_cred();
2633
2634 return dentry_has_perm(cred, NULL, dentry, FILE__READ);
2635 }
2636
2637 static int selinux_inode_follow_link(struct dentry *dentry, struct nameidata *nameidata)
2638 {
2639 const struct cred *cred = current_cred();
2640
2641 return dentry_has_perm(cred, NULL, dentry, FILE__READ);
2642 }
2643
2644 static int selinux_inode_permission(struct inode *inode, int mask)
2645 {
2646 const struct cred *cred = current_cred();
2647
2648 if (!mask) {
2649 /* No permission to check. Existence test. */
2650 return 0;
2651 }
2652
2653 return inode_has_perm(cred, inode,
2654 file_mask_to_av(inode->i_mode, mask), NULL);
2655 }
2656
2657 static int selinux_inode_setattr(struct dentry *dentry, struct iattr *iattr)
2658 {
2659 const struct cred *cred = current_cred();
2660 unsigned int ia_valid = iattr->ia_valid;
2661
2662 /* ATTR_FORCE is just used for ATTR_KILL_S[UG]ID. */
2663 if (ia_valid & ATTR_FORCE) {
2664 ia_valid &= ~(ATTR_KILL_SUID | ATTR_KILL_SGID | ATTR_MODE |
2665 ATTR_FORCE);
2666 if (!ia_valid)
2667 return 0;
2668 }
2669
2670 if (ia_valid & (ATTR_MODE | ATTR_UID | ATTR_GID |
2671 ATTR_ATIME_SET | ATTR_MTIME_SET | ATTR_TIMES_SET))
2672 return dentry_has_perm(cred, NULL, dentry, FILE__SETATTR);
2673
2674 return dentry_has_perm(cred, NULL, dentry, FILE__WRITE);
2675 }
2676
2677 static int selinux_inode_getattr(struct vfsmount *mnt, struct dentry *dentry)
2678 {
2679 const struct cred *cred = current_cred();
2680
2681 return dentry_has_perm(cred, mnt, dentry, FILE__GETATTR);
2682 }
2683
2684 static int selinux_inode_setotherxattr(struct dentry *dentry, const char *name)
2685 {
2686 const struct cred *cred = current_cred();
2687
2688 if (!strncmp(name, XATTR_SECURITY_PREFIX,
2689 sizeof XATTR_SECURITY_PREFIX - 1)) {
2690 if (!strcmp(name, XATTR_NAME_CAPS)) {
2691 if (!capable(CAP_SETFCAP))
2692 return -EPERM;
2693 } else if (!capable(CAP_SYS_ADMIN)) {
2694 /* A different attribute in the security namespace.
2695 Restrict to administrator. */
2696 return -EPERM;
2697 }
2698 }
2699
2700 /* Not an attribute we recognize, so just check the
2701 ordinary setattr permission. */
2702 return dentry_has_perm(cred, NULL, dentry, FILE__SETATTR);
2703 }
2704
2705 static int selinux_inode_setxattr(struct dentry *dentry, const char *name,
2706 const void *value, size_t size, int flags)
2707 {
2708 struct inode *inode = dentry->d_inode;
2709 struct inode_security_struct *isec = inode->i_security;
2710 struct superblock_security_struct *sbsec;
2711 struct common_audit_data ad;
2712 u32 newsid, sid = current_sid();
2713 int rc = 0;
2714
2715 if (strcmp(name, XATTR_NAME_SELINUX))
2716 return selinux_inode_setotherxattr(dentry, name);
2717
2718 sbsec = inode->i_sb->s_security;
2719 if (!(sbsec->flags & SE_SBLABELSUPP))
2720 return -EOPNOTSUPP;
2721
2722 if (!is_owner_or_cap(inode))
2723 return -EPERM;
2724
2725 COMMON_AUDIT_DATA_INIT(&ad, FS);
2726 ad.u.fs.path.dentry = dentry;
2727
2728 rc = avc_has_perm(sid, isec->sid, isec->sclass,
2729 FILE__RELABELFROM, &ad);
2730 if (rc)
2731 return rc;
2732
2733 rc = security_context_to_sid(value, size, &newsid);
2734 if (rc == -EINVAL) {
2735 if (!capable(CAP_MAC_ADMIN))
2736 return rc;
2737 rc = security_context_to_sid_force(value, size, &newsid);
2738 }
2739 if (rc)
2740 return rc;
2741
2742 rc = avc_has_perm(sid, newsid, isec->sclass,
2743 FILE__RELABELTO, &ad);
2744 if (rc)
2745 return rc;
2746
2747 rc = security_validate_transition(isec->sid, newsid, sid,
2748 isec->sclass);
2749 if (rc)
2750 return rc;
2751
2752 return avc_has_perm(newsid,
2753 sbsec->sid,
2754 SECCLASS_FILESYSTEM,
2755 FILESYSTEM__ASSOCIATE,
2756 &ad);
2757 }
2758
2759 static void selinux_inode_post_setxattr(struct dentry *dentry, const char *name,
2760 const void *value, size_t size,
2761 int flags)
2762 {
2763 struct inode *inode = dentry->d_inode;
2764 struct inode_security_struct *isec = inode->i_security;
2765 u32 newsid;
2766 int rc;
2767
2768 if (strcmp(name, XATTR_NAME_SELINUX)) {
2769 /* Not an attribute we recognize, so nothing to do. */
2770 return;
2771 }
2772
2773 rc = security_context_to_sid_force(value, size, &newsid);
2774 if (rc) {
2775 printk(KERN_ERR "SELinux: unable to map context to SID"
2776 "for (%s, %lu), rc=%d\n",
2777 inode->i_sb->s_id, inode->i_ino, -rc);
2778 return;
2779 }
2780
2781 isec->sid = newsid;
2782 return;
2783 }
2784
2785 static int selinux_inode_getxattr(struct dentry *dentry, const char *name)
2786 {
2787 const struct cred *cred = current_cred();
2788
2789 return dentry_has_perm(cred, NULL, dentry, FILE__GETATTR);
2790 }
2791
2792 static int selinux_inode_listxattr(struct dentry *dentry)
2793 {
2794 const struct cred *cred = current_cred();
2795
2796 return dentry_has_perm(cred, NULL, dentry, FILE__GETATTR);
2797 }
2798
2799 static int selinux_inode_removexattr(struct dentry *dentry, const char *name)
2800 {
2801 if (strcmp(name, XATTR_NAME_SELINUX))
2802 return selinux_inode_setotherxattr(dentry, name);
2803
2804 /* No one is allowed to remove a SELinux security label.
2805 You can change the label, but all data must be labeled. */
2806 return -EACCES;
2807 }
2808
2809 /*
2810 * Copy the inode security context value to the user.
2811 *
2812 * Permission check is handled by selinux_inode_getxattr hook.
2813 */
2814 static int selinux_inode_getsecurity(const struct inode *inode, const char *name, void **buffer, bool alloc)
2815 {
2816 u32 size;
2817 int error;
2818 char *context = NULL;
2819 struct inode_security_struct *isec = inode->i_security;
2820
2821 if (strcmp(name, XATTR_SELINUX_SUFFIX))
2822 return -EOPNOTSUPP;
2823
2824 /*
2825 * If the caller has CAP_MAC_ADMIN, then get the raw context
2826 * value even if it is not defined by current policy; otherwise,
2827 * use the in-core value under current policy.
2828 * Use the non-auditing forms of the permission checks since
2829 * getxattr may be called by unprivileged processes commonly
2830 * and lack of permission just means that we fall back to the
2831 * in-core context value, not a denial.
2832 */
2833 error = selinux_capable(current, current_cred(), CAP_MAC_ADMIN,
2834 SECURITY_CAP_NOAUDIT);
2835 if (!error)
2836 error = security_sid_to_context_force(isec->sid, &context,
2837 &size);
2838 else
2839 error = security_sid_to_context(isec->sid, &context, &size);
2840 if (error)
2841 return error;
2842 error = size;
2843 if (alloc) {
2844 *buffer = context;
2845 goto out_nofree;
2846 }
2847 kfree(context);
2848 out_nofree:
2849 return error;
2850 }
2851
2852 static int selinux_inode_setsecurity(struct inode *inode, const char *name,
2853 const void *value, size_t size, int flags)
2854 {
2855 struct inode_security_struct *isec = inode->i_security;
2856 u32 newsid;
2857 int rc;
2858
2859 if (strcmp(name, XATTR_SELINUX_SUFFIX))
2860 return -EOPNOTSUPP;
2861
2862 if (!value || !size)
2863 return -EACCES;
2864
2865 rc = security_context_to_sid((void *)value, size, &newsid);
2866 if (rc)
2867 return rc;
2868
2869 isec->sid = newsid;
2870 isec->initialized = 1;
2871 return 0;
2872 }
2873
2874 static int selinux_inode_listsecurity(struct inode *inode, char *buffer, size_t buffer_size)
2875 {
2876 const int len = sizeof(XATTR_NAME_SELINUX);
2877 if (buffer && len <= buffer_size)
2878 memcpy(buffer, XATTR_NAME_SELINUX, len);
2879 return len;
2880 }
2881
2882 static void selinux_inode_getsecid(const struct inode *inode, u32 *secid)
2883 {
2884 struct inode_security_struct *isec = inode->i_security;
2885 *secid = isec->sid;
2886 }
2887
2888 /* file security operations */
2889
2890 static int selinux_revalidate_file_permission(struct file *file, int mask)
2891 {
2892 const struct cred *cred = current_cred();
2893 struct inode *inode = file->f_path.dentry->d_inode;
2894
2895 /* file_mask_to_av won't add FILE__WRITE if MAY_APPEND is set */
2896 if ((file->f_flags & O_APPEND) && (mask & MAY_WRITE))
2897 mask |= MAY_APPEND;
2898
2899 return file_has_perm(cred, file,
2900 file_mask_to_av(inode->i_mode, mask));
2901 }
2902
2903 static int selinux_file_permission(struct file *file, int mask)
2904 {
2905 struct inode *inode = file->f_path.dentry->d_inode;
2906 struct file_security_struct *fsec = file->f_security;
2907 struct inode_security_struct *isec = inode->i_security;
2908 u32 sid = current_sid();
2909
2910 if (!mask)
2911 /* No permission to check. Existence test. */
2912 return 0;
2913
2914 if (sid == fsec->sid && fsec->isid == isec->sid &&
2915 fsec->pseqno == avc_policy_seqno())
2916 /* No change since dentry_open check. */
2917 return 0;
2918
2919 return selinux_revalidate_file_permission(file, mask);
2920 }
2921
2922 static int selinux_file_alloc_security(struct file *file)
2923 {
2924 return file_alloc_security(file);
2925 }
2926
2927 static void selinux_file_free_security(struct file *file)
2928 {
2929 file_free_security(file);
2930 }
2931
2932 static int selinux_file_ioctl(struct file *file, unsigned int cmd,
2933 unsigned long arg)
2934 {
2935 const struct cred *cred = current_cred();
2936 u32 av = 0;
2937
2938 if (_IOC_DIR(cmd) & _IOC_WRITE)
2939 av |= FILE__WRITE;
2940 if (_IOC_DIR(cmd) & _IOC_READ)
2941 av |= FILE__READ;
2942 if (!av)
2943 av = FILE__IOCTL;
2944
2945 return file_has_perm(cred, file, av);
2946 }
2947
2948 static int default_noexec;
2949
2950 static int file_map_prot_check(struct file *file, unsigned long prot, int shared)
2951 {
2952 const struct cred *cred = current_cred();
2953 int rc = 0;
2954
2955 if (default_noexec &&
2956 (prot & PROT_EXEC) && (!file || (!shared && (prot & PROT_WRITE)))) {
2957 /*
2958 * We are making executable an anonymous mapping or a
2959 * private file mapping that will also be writable.
2960 * This has an additional check.
2961 */
2962 rc = cred_has_perm(cred, cred, PROCESS__EXECMEM);
2963 if (rc)
2964 goto error;
2965 }
2966
2967 if (file) {
2968 /* read access is always possible with a mapping */
2969 u32 av = FILE__READ;
2970
2971 /* write access only matters if the mapping is shared */
2972 if (shared && (prot & PROT_WRITE))
2973 av |= FILE__WRITE;
2974
2975 if (prot & PROT_EXEC)
2976 av |= FILE__EXECUTE;
2977
2978 return file_has_perm(cred, file, av);
2979 }
2980
2981 error:
2982 return rc;
2983 }
2984
2985 static int selinux_file_mmap(struct file *file, unsigned long reqprot,
2986 unsigned long prot, unsigned long flags,
2987 unsigned long addr, unsigned long addr_only)
2988 {
2989 int rc = 0;
2990 u32 sid = current_sid();
2991
2992 /*
2993 * notice that we are intentionally putting the SELinux check before
2994 * the secondary cap_file_mmap check. This is such a likely attempt
2995 * at bad behaviour/exploit that we always want to get the AVC, even
2996 * if DAC would have also denied the operation.
2997 */
2998 if (addr < CONFIG_LSM_MMAP_MIN_ADDR) {
2999 rc = avc_has_perm(sid, sid, SECCLASS_MEMPROTECT,
3000 MEMPROTECT__MMAP_ZERO, NULL);
3001 if (rc)
3002 return rc;
3003 }
3004
3005 /* do DAC check on address space usage */
3006 rc = cap_file_mmap(file, reqprot, prot, flags, addr, addr_only);
3007 if (rc || addr_only)
3008 return rc;
3009
3010 if (selinux_checkreqprot)
3011 prot = reqprot;
3012
3013 return file_map_prot_check(file, prot,
3014 (flags & MAP_TYPE) == MAP_SHARED);
3015 }
3016
3017 static int selinux_file_mprotect(struct vm_area_struct *vma,
3018 unsigned long reqprot,
3019 unsigned long prot)
3020 {
3021 const struct cred *cred = current_cred();
3022
3023 if (selinux_checkreqprot)
3024 prot = reqprot;
3025
3026 if (default_noexec &&
3027 (prot & PROT_EXEC) && !(vma->vm_flags & VM_EXEC)) {
3028 int rc = 0;
3029 if (vma->vm_start >= vma->vm_mm->start_brk &&
3030 vma->vm_end <= vma->vm_mm->brk) {
3031 rc = cred_has_perm(cred, cred, PROCESS__EXECHEAP);
3032 } else if (!vma->vm_file &&
3033 vma->vm_start <= vma->vm_mm->start_stack &&
3034 vma->vm_end >= vma->vm_mm->start_stack) {
3035 rc = current_has_perm(current, PROCESS__EXECSTACK);
3036 } else if (vma->vm_file && vma->anon_vma) {
3037 /*
3038 * We are making executable a file mapping that has
3039 * had some COW done. Since pages might have been
3040 * written, check ability to execute the possibly
3041 * modified content. This typically should only
3042 * occur for text relocations.
3043 */
3044 rc = file_has_perm(cred, vma->vm_file, FILE__EXECMOD);
3045 }
3046 if (rc)
3047 return rc;
3048 }
3049
3050 return file_map_prot_check(vma->vm_file, prot, vma->vm_flags&VM_SHARED);
3051 }
3052
3053 static int selinux_file_lock(struct file *file, unsigned int cmd)
3054 {
3055 const struct cred *cred = current_cred();
3056
3057 return file_has_perm(cred, file, FILE__LOCK);
3058 }
3059
3060 static int selinux_file_fcntl(struct file *file, unsigned int cmd,
3061 unsigned long arg)
3062 {
3063 const struct cred *cred = current_cred();
3064 int err = 0;
3065
3066 switch (cmd) {
3067 case F_SETFL:
3068 if (!file->f_path.dentry || !file->f_path.dentry->d_inode) {
3069 err = -EINVAL;
3070 break;
3071 }
3072
3073 if ((file->f_flags & O_APPEND) && !(arg & O_APPEND)) {
3074 err = file_has_perm(cred, file, FILE__WRITE);
3075 break;
3076 }
3077 /* fall through */
3078 case F_SETOWN:
3079 case F_SETSIG:
3080 case F_GETFL:
3081 case F_GETOWN:
3082 case F_GETSIG:
3083 /* Just check FD__USE permission */
3084 err = file_has_perm(cred, file, 0);
3085 break;
3086 case F_GETLK:
3087 case F_SETLK:
3088 case F_SETLKW:
3089 #if BITS_PER_LONG == 32
3090 case F_GETLK64:
3091 case F_SETLK64:
3092 case F_SETLKW64:
3093 #endif
3094 if (!file->f_path.dentry || !file->f_path.dentry->d_inode) {
3095 err = -EINVAL;
3096 break;
3097 }
3098 err = file_has_perm(cred, file, FILE__LOCK);
3099 break;
3100 }
3101
3102 return err;
3103 }
3104
3105 static int selinux_file_set_fowner(struct file *file)
3106 {
3107 struct file_security_struct *fsec;
3108
3109 fsec = file->f_security;
3110 fsec->fown_sid = current_sid();
3111
3112 return 0;
3113 }
3114
3115 static int selinux_file_send_sigiotask(struct task_struct *tsk,
3116 struct fown_struct *fown, int signum)
3117 {
3118 struct file *file;
3119 u32 sid = task_sid(tsk);
3120 u32 perm;
3121 struct file_security_struct *fsec;
3122
3123 /* struct fown_struct is never outside the context of a struct file */
3124 file = container_of(fown, struct file, f_owner);
3125
3126 fsec = file->f_security;
3127
3128 if (!signum)
3129 perm = signal_to_av(SIGIO); /* as per send_sigio_to_task */
3130 else
3131 perm = signal_to_av(signum);
3132
3133 return avc_has_perm(fsec->fown_sid, sid,
3134 SECCLASS_PROCESS, perm, NULL);
3135 }
3136
3137 static int selinux_file_receive(struct file *file)
3138 {
3139 const struct cred *cred = current_cred();
3140
3141 return file_has_perm(cred, file, file_to_av(file));
3142 }
3143
3144 static int selinux_dentry_open(struct file *file, const struct cred *cred)
3145 {
3146 struct file_security_struct *fsec;
3147 struct inode *inode;
3148 struct inode_security_struct *isec;
3149
3150 inode = file->f_path.dentry->d_inode;
3151 fsec = file->f_security;
3152 isec = inode->i_security;
3153 /*
3154 * Save inode label and policy sequence number
3155 * at open-time so that selinux_file_permission
3156 * can determine whether revalidation is necessary.
3157 * Task label is already saved in the file security
3158 * struct as its SID.
3159 */
3160 fsec->isid = isec->sid;
3161 fsec->pseqno = avc_policy_seqno();
3162 /*
3163 * Since the inode label or policy seqno may have changed
3164 * between the selinux_inode_permission check and the saving
3165 * of state above, recheck that access is still permitted.
3166 * Otherwise, access might never be revalidated against the
3167 * new inode label or new policy.
3168 * This check is not redundant - do not remove.
3169 */
3170 return inode_has_perm(cred, inode, open_file_to_av(file), NULL);
3171 }
3172
3173 /* task security operations */
3174
3175 static int selinux_task_create(unsigned long clone_flags)
3176 {
3177 return current_has_perm(current, PROCESS__FORK);
3178 }
3179
3180 /*
3181 * allocate the SELinux part of blank credentials
3182 */
3183 static int selinux_cred_alloc_blank(struct cred *cred, gfp_t gfp)
3184 {
3185 struct task_security_struct *tsec;
3186
3187 tsec = kzalloc(sizeof(struct task_security_struct), gfp);
3188 if (!tsec)
3189 return -ENOMEM;
3190
3191 cred->security = tsec;
3192 return 0;
3193 }
3194
3195 /*
3196 * detach and free the LSM part of a set of credentials
3197 */
3198 static void selinux_cred_free(struct cred *cred)
3199 {
3200 struct task_security_struct *tsec = cred->security;
3201
3202 BUG_ON((unsigned long) cred->security < PAGE_SIZE);
3203 cred->security = (void *) 0x7UL;
3204 kfree(tsec);
3205 }
3206
3207 /*
3208 * prepare a new set of credentials for modification
3209 */
3210 static int selinux_cred_prepare(struct cred *new, const struct cred *old,
3211 gfp_t gfp)
3212 {
3213 const struct task_security_struct *old_tsec;
3214 struct task_security_struct *tsec;
3215
3216 old_tsec = old->security;
3217
3218 tsec = kmemdup(old_tsec, sizeof(struct task_security_struct), gfp);
3219 if (!tsec)
3220 return -ENOMEM;
3221
3222 new->security = tsec;
3223 return 0;
3224 }
3225
3226 /*
3227 * transfer the SELinux data to a blank set of creds
3228 */
3229 static void selinux_cred_transfer(struct cred *new, const struct cred *old)
3230 {
3231 const struct task_security_struct *old_tsec = old->security;
3232 struct task_security_struct *tsec = new->security;
3233
3234 *tsec = *old_tsec;
3235 }
3236
3237 /*
3238 * set the security data for a kernel service
3239 * - all the creation contexts are set to unlabelled
3240 */
3241 static int selinux_kernel_act_as(struct cred *new, u32 secid)
3242 {
3243 struct task_security_struct *tsec = new->security;
3244 u32 sid = current_sid();
3245 int ret;
3246
3247 ret = avc_has_perm(sid, secid,
3248 SECCLASS_KERNEL_SERVICE,
3249 KERNEL_SERVICE__USE_AS_OVERRIDE,
3250 NULL);
3251 if (ret == 0) {
3252 tsec->sid = secid;
3253 tsec->create_sid = 0;
3254 tsec->keycreate_sid = 0;
3255 tsec->sockcreate_sid = 0;
3256 }
3257 return ret;
3258 }
3259
3260 /*
3261 * set the file creation context in a security record to the same as the
3262 * objective context of the specified inode
3263 */
3264 static int selinux_kernel_create_files_as(struct cred *new, struct inode *inode)
3265 {
3266 struct inode_security_struct *isec = inode->i_security;
3267 struct task_security_struct *tsec = new->security;
3268 u32 sid = current_sid();
3269 int ret;
3270
3271 ret = avc_has_perm(sid, isec->sid,
3272 SECCLASS_KERNEL_SERVICE,
3273 KERNEL_SERVICE__CREATE_FILES_AS,
3274 NULL);
3275
3276 if (ret == 0)
3277 tsec->create_sid = isec->sid;
3278 return ret;
3279 }
3280
3281 static int selinux_kernel_module_request(char *kmod_name)
3282 {
3283 u32 sid;
3284 struct common_audit_data ad;
3285
3286 sid = task_sid(current);
3287
3288 COMMON_AUDIT_DATA_INIT(&ad, KMOD);
3289 ad.u.kmod_name = kmod_name;
3290
3291 return avc_has_perm(sid, SECINITSID_KERNEL, SECCLASS_SYSTEM,
3292 SYSTEM__MODULE_REQUEST, &ad);
3293 }
3294
3295 static int selinux_task_setpgid(struct task_struct *p, pid_t pgid)
3296 {
3297 return current_has_perm(p, PROCESS__SETPGID);
3298 }
3299
3300 static int selinux_task_getpgid(struct task_struct *p)
3301 {
3302 return current_has_perm(p, PROCESS__GETPGID);
3303 }
3304
3305 static int selinux_task_getsid(struct task_struct *p)
3306 {
3307 return current_has_perm(p, PROCESS__GETSESSION);
3308 }
3309
3310 static void selinux_task_getsecid(struct task_struct *p, u32 *secid)
3311 {
3312 *secid = task_sid(p);
3313 }
3314
3315 static int selinux_task_setnice(struct task_struct *p, int nice)
3316 {
3317 int rc;
3318
3319 rc = cap_task_setnice(p, nice);
3320 if (rc)
3321 return rc;
3322
3323 return current_has_perm(p, PROCESS__SETSCHED);
3324 }
3325
3326 static int selinux_task_setioprio(struct task_struct *p, int ioprio)
3327 {
3328 int rc;
3329
3330 rc = cap_task_setioprio(p, ioprio);
3331 if (rc)
3332 return rc;
3333
3334 return current_has_perm(p, PROCESS__SETSCHED);
3335 }
3336
3337 static int selinux_task_getioprio(struct task_struct *p)
3338 {
3339 return current_has_perm(p, PROCESS__GETSCHED);
3340 }
3341
3342 static int selinux_task_setrlimit(unsigned int resource, struct rlimit *new_rlim)
3343 {
3344 struct rlimit *old_rlim = current->signal->rlim + resource;
3345
3346 /* Control the ability to change the hard limit (whether
3347 lowering or raising it), so that the hard limit can
3348 later be used as a safe reset point for the soft limit
3349 upon context transitions. See selinux_bprm_committing_creds. */
3350 if (old_rlim->rlim_max != new_rlim->rlim_max)
3351 return current_has_perm(current, PROCESS__SETRLIMIT);
3352
3353 return 0;
3354 }
3355
3356 static int selinux_task_setscheduler(struct task_struct *p, int policy, struct sched_param *lp)
3357 {
3358 int rc;
3359
3360 rc = cap_task_setscheduler(p, policy, lp);
3361 if (rc)
3362 return rc;
3363
3364 return current_has_perm(p, PROCESS__SETSCHED);
3365 }
3366
3367 static int selinux_task_getscheduler(struct task_struct *p)
3368 {
3369 return current_has_perm(p, PROCESS__GETSCHED);
3370 }
3371
3372 static int selinux_task_movememory(struct task_struct *p)
3373 {
3374 return current_has_perm(p, PROCESS__SETSCHED);
3375 }
3376
3377 static int selinux_task_kill(struct task_struct *p, struct siginfo *info,
3378 int sig, u32 secid)
3379 {
3380 u32 perm;
3381 int rc;
3382
3383 if (!sig)
3384 perm = PROCESS__SIGNULL; /* null signal; existence test */
3385 else
3386 perm = signal_to_av(sig);
3387 if (secid)
3388 rc = avc_has_perm(secid, task_sid(p),
3389 SECCLASS_PROCESS, perm, NULL);
3390 else
3391 rc = current_has_perm(p, perm);
3392 return rc;
3393 }
3394
3395 static int selinux_task_wait(struct task_struct *p)
3396 {
3397 return task_has_perm(p, current, PROCESS__SIGCHLD);
3398 }
3399
3400 static void selinux_task_to_inode(struct task_struct *p,
3401 struct inode *inode)
3402 {
3403 struct inode_security_struct *isec = inode->i_security;
3404 u32 sid = task_sid(p);
3405
3406 isec->sid = sid;
3407 isec->initialized = 1;
3408 }
3409
3410 /* Returns error only if unable to parse addresses */
3411 static int selinux_parse_skb_ipv4(struct sk_buff *skb,
3412 struct common_audit_data *ad, u8 *proto)
3413 {
3414 int offset, ihlen, ret = -EINVAL;
3415 struct iphdr _iph, *ih;
3416
3417 offset = skb_network_offset(skb);
3418 ih = skb_header_pointer(skb, offset, sizeof(_iph), &_iph);
3419 if (ih == NULL)
3420 goto out;
3421
3422 ihlen = ih->ihl * 4;
3423 if (ihlen < sizeof(_iph))
3424 goto out;
3425
3426 ad->u.net.v4info.saddr = ih->saddr;
3427 ad->u.net.v4info.daddr = ih->daddr;
3428 ret = 0;
3429
3430 if (proto)
3431 *proto = ih->protocol;
3432
3433 switch (ih->protocol) {
3434 case IPPROTO_TCP: {
3435 struct tcphdr _tcph, *th;
3436
3437 if (ntohs(ih->frag_off) & IP_OFFSET)
3438 break;
3439
3440 offset += ihlen;
3441 th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph);
3442 if (th == NULL)
3443 break;
3444
3445 ad->u.net.sport = th->source;
3446 ad->u.net.dport = th->dest;
3447 break;
3448 }
3449
3450 case IPPROTO_UDP: {
3451 struct udphdr _udph, *uh;
3452
3453 if (ntohs(ih->frag_off) & IP_OFFSET)
3454 break;
3455
3456 offset += ihlen;
3457 uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph);
3458 if (uh == NULL)
3459 break;
3460
3461 ad->u.net.sport = uh->source;
3462 ad->u.net.dport = uh->dest;
3463 break;
3464 }
3465
3466 case IPPROTO_DCCP: {
3467 struct dccp_hdr _dccph, *dh;
3468
3469 if (ntohs(ih->frag_off) & IP_OFFSET)
3470 break;
3471
3472 offset += ihlen;
3473 dh = skb_header_pointer(skb, offset, sizeof(_dccph), &_dccph);
3474 if (dh == NULL)
3475 break;
3476
3477 ad->u.net.sport = dh->dccph_sport;
3478 ad->u.net.dport = dh->dccph_dport;
3479 break;
3480 }
3481
3482 default:
3483 break;
3484 }
3485 out:
3486 return ret;
3487 }
3488
3489 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
3490
3491 /* Returns error only if unable to parse addresses */
3492 static int selinux_parse_skb_ipv6(struct sk_buff *skb,
3493 struct common_audit_data *ad, u8 *proto)
3494 {
3495 u8 nexthdr;
3496 int ret = -EINVAL, offset;
3497 struct ipv6hdr _ipv6h, *ip6;
3498
3499 offset = skb_network_offset(skb);
3500 ip6 = skb_header_pointer(skb, offset, sizeof(_ipv6h), &_ipv6h);
3501 if (ip6 == NULL)
3502 goto out;
3503
3504 ipv6_addr_copy(&ad->u.net.v6info.saddr, &ip6->saddr);
3505 ipv6_addr_copy(&ad->u.net.v6info.daddr, &ip6->daddr);
3506 ret = 0;
3507
3508 nexthdr = ip6->nexthdr;
3509 offset += sizeof(_ipv6h);
3510 offset = ipv6_skip_exthdr(skb, offset, &nexthdr);
3511 if (offset < 0)
3512 goto out;
3513
3514 if (proto)
3515 *proto = nexthdr;
3516
3517 switch (nexthdr) {
3518 case IPPROTO_TCP: {
3519 struct tcphdr _tcph, *th;
3520
3521 th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph);
3522 if (th == NULL)
3523 break;
3524
3525 ad->u.net.sport = th->source;
3526 ad->u.net.dport = th->dest;
3527 break;
3528 }
3529
3530 case IPPROTO_UDP: {
3531 struct udphdr _udph, *uh;
3532
3533 uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph);
3534 if (uh == NULL)
3535 break;
3536
3537 ad->u.net.sport = uh->source;
3538 ad->u.net.dport = uh->dest;
3539 break;
3540 }
3541
3542 case IPPROTO_DCCP: {
3543 struct dccp_hdr _dccph, *dh;
3544
3545 dh = skb_header_pointer(skb, offset, sizeof(_dccph), &_dccph);
3546 if (dh == NULL)
3547 break;
3548
3549 ad->u.net.sport = dh->dccph_sport;
3550 ad->u.net.dport = dh->dccph_dport;
3551 break;
3552 }
3553
3554 /* includes fragments */
3555 default:
3556 break;
3557 }
3558 out:
3559 return ret;
3560 }
3561
3562 #endif /* IPV6 */
3563
3564 static int selinux_parse_skb(struct sk_buff *skb, struct common_audit_data *ad,
3565 char **_addrp, int src, u8 *proto)
3566 {
3567 char *addrp;
3568 int ret;
3569
3570 switch (ad->u.net.family) {
3571 case PF_INET:
3572 ret = selinux_parse_skb_ipv4(skb, ad, proto);
3573 if (ret)
3574 goto parse_error;
3575 addrp = (char *)(src ? &ad->u.net.v4info.saddr :
3576 &ad->u.net.v4info.daddr);
3577 goto okay;
3578
3579 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
3580 case PF_INET6:
3581 ret = selinux_parse_skb_ipv6(skb, ad, proto);
3582 if (ret)
3583 goto parse_error;
3584 addrp = (char *)(src ? &ad->u.net.v6info.saddr :
3585 &ad->u.net.v6info.daddr);
3586 goto okay;
3587 #endif /* IPV6 */
3588 default:
3589 addrp = NULL;
3590 goto okay;
3591 }
3592
3593 parse_error:
3594 printk(KERN_WARNING
3595 "SELinux: failure in selinux_parse_skb(),"
3596 " unable to parse packet\n");
3597 return ret;
3598
3599 okay:
3600 if (_addrp)
3601 *_addrp = addrp;
3602 return 0;
3603 }
3604
3605 /**
3606 * selinux_skb_peerlbl_sid - Determine the peer label of a packet
3607 * @skb: the packet
3608 * @family: protocol family
3609 * @sid: the packet's peer label SID
3610 *
3611 * Description:
3612 * Check the various different forms of network peer labeling and determine
3613 * the peer label/SID for the packet; most of the magic actually occurs in
3614 * the security server function security_net_peersid_cmp(). The function
3615 * returns zero if the value in @sid is valid (although it may be SECSID_NULL)
3616 * or -EACCES if @sid is invalid due to inconsistencies with the different
3617 * peer labels.
3618 *
3619 */
3620 static int selinux_skb_peerlbl_sid(struct sk_buff *skb, u16 family, u32 *sid)
3621 {
3622 int err;
3623 u32 xfrm_sid;
3624 u32 nlbl_sid;
3625 u32 nlbl_type;
3626
3627 selinux_skb_xfrm_sid(skb, &xfrm_sid);
3628 selinux_netlbl_skbuff_getsid(skb, family, &nlbl_type, &nlbl_sid);
3629
3630 err = security_net_peersid_resolve(nlbl_sid, nlbl_type, xfrm_sid, sid);
3631 if (unlikely(err)) {
3632 printk(KERN_WARNING
3633 "SELinux: failure in selinux_skb_peerlbl_sid(),"
3634 " unable to determine packet's peer label\n");
3635 return -EACCES;
3636 }
3637
3638 return 0;
3639 }
3640
3641 /* socket security operations */
3642
3643 static u32 socket_sockcreate_sid(const struct task_security_struct *tsec)
3644 {
3645 return tsec->sockcreate_sid ? : tsec->sid;
3646 }
3647
3648 static int sock_has_perm(struct task_struct *task, struct sock *sk, u32 perms)
3649 {
3650 struct sk_security_struct *sksec = sk->sk_security;
3651 struct common_audit_data ad;
3652 u32 tsid = task_sid(task);
3653
3654 if (sksec->sid == SECINITSID_KERNEL)
3655 return 0;
3656
3657 COMMON_AUDIT_DATA_INIT(&ad, NET);
3658 ad.u.net.sk = sk;
3659
3660 return avc_has_perm(tsid, sksec->sid, sksec->sclass, perms, &ad);
3661 }
3662
3663 static int selinux_socket_create(int family, int type,
3664 int protocol, int kern)
3665 {
3666 const struct task_security_struct *tsec = current_security();
3667 u32 newsid;
3668 u16 secclass;
3669
3670 if (kern)
3671 return 0;
3672
3673 newsid = socket_sockcreate_sid(tsec);
3674 secclass = socket_type_to_security_class(family, type, protocol);
3675 return avc_has_perm(tsec->sid, newsid, secclass, SOCKET__CREATE, NULL);
3676 }
3677
3678 static int selinux_socket_post_create(struct socket *sock, int family,
3679 int type, int protocol, int kern)
3680 {
3681 const struct task_security_struct *tsec = current_security();
3682 struct inode_security_struct *isec = SOCK_INODE(sock)->i_security;
3683 struct sk_security_struct *sksec;
3684 int err = 0;
3685
3686 if (kern)
3687 isec->sid = SECINITSID_KERNEL;
3688 else
3689 isec->sid = socket_sockcreate_sid(tsec);
3690
3691 isec->sclass = socket_type_to_security_class(family, type, protocol);
3692 isec->initialized = 1;
3693
3694 if (sock->sk) {
3695 sksec = sock->sk->sk_security;
3696 sksec->sid = isec->sid;
3697 sksec->sclass = isec->sclass;
3698 err = selinux_netlbl_socket_post_create(sock->sk, family);
3699 }
3700
3701 return err;
3702 }
3703
3704 /* Range of port numbers used to automatically bind.
3705 Need to determine whether we should perform a name_bind
3706 permission check between the socket and the port number. */
3707
3708 static int selinux_socket_bind(struct socket *sock, struct sockaddr *address, int addrlen)
3709 {
3710 struct sock *sk = sock->sk;
3711 u16 family;
3712 int err;
3713
3714 err = sock_has_perm(current, sk, SOCKET__BIND);
3715 if (err)
3716 goto out;
3717
3718 /*
3719 * If PF_INET or PF_INET6, check name_bind permission for the port.
3720 * Multiple address binding for SCTP is not supported yet: we just
3721 * check the first address now.
3722 */
3723 family = sk->sk_family;
3724 if (family == PF_INET || family == PF_INET6) {
3725 char *addrp;
3726 struct sk_security_struct *sksec = sk->sk_security;
3727 struct common_audit_data ad;
3728 struct sockaddr_in *addr4 = NULL;
3729 struct sockaddr_in6 *addr6 = NULL;
3730 unsigned short snum;
3731 u32 sid, node_perm;
3732
3733 if (family == PF_INET) {
3734 addr4 = (struct sockaddr_in *)address;
3735 snum = ntohs(addr4->sin_port);
3736 addrp = (char *)&addr4->sin_addr.s_addr;
3737 } else {
3738 addr6 = (struct sockaddr_in6 *)address;
3739 snum = ntohs(addr6->sin6_port);
3740 addrp = (char *)&addr6->sin6_addr.s6_addr;
3741 }
3742
3743 if (snum) {
3744 int low, high;
3745
3746 inet_get_local_port_range(&low, &high);
3747
3748 if (snum < max(PROT_SOCK, low) || snum > high) {
3749 err = sel_netport_sid(sk->sk_protocol,
3750 snum, &sid);
3751 if (err)
3752 goto out;
3753 COMMON_AUDIT_DATA_INIT(&ad, NET);
3754 ad.u.net.sport = htons(snum);
3755 ad.u.net.family = family;
3756 err = avc_has_perm(sksec->sid, sid,
3757 sksec->sclass,
3758 SOCKET__NAME_BIND, &ad);
3759 if (err)
3760 goto out;
3761 }
3762 }
3763
3764 switch (sksec->sclass) {
3765 case SECCLASS_TCP_SOCKET:
3766 node_perm = TCP_SOCKET__NODE_BIND;
3767 break;
3768
3769 case SECCLASS_UDP_SOCKET:
3770 node_perm = UDP_SOCKET__NODE_BIND;
3771 break;
3772
3773 case SECCLASS_DCCP_SOCKET:
3774 node_perm = DCCP_SOCKET__NODE_BIND;
3775 break;
3776
3777 default:
3778 node_perm = RAWIP_SOCKET__NODE_BIND;
3779 break;
3780 }
3781
3782 err = sel_netnode_sid(addrp, family, &sid);
3783 if (err)
3784 goto out;
3785
3786 COMMON_AUDIT_DATA_INIT(&ad, NET);
3787 ad.u.net.sport = htons(snum);
3788 ad.u.net.family = family;
3789
3790 if (family == PF_INET)
3791 ad.u.net.v4info.saddr = addr4->sin_addr.s_addr;
3792 else
3793 ipv6_addr_copy(&ad.u.net.v6info.saddr, &addr6->sin6_addr);
3794
3795 err = avc_has_perm(sksec->sid, sid,
3796 sksec->sclass, node_perm, &ad);
3797 if (err)
3798 goto out;
3799 }
3800 out:
3801 return err;
3802 }
3803
3804 static int selinux_socket_connect(struct socket *sock, struct sockaddr *address, int addrlen)
3805 {
3806 struct sock *sk = sock->sk;
3807 struct sk_security_struct *sksec = sk->sk_security;
3808 int err;
3809
3810 err = sock_has_perm(current, sk, SOCKET__CONNECT);
3811 if (err)
3812 return err;
3813
3814 /*
3815 * If a TCP or DCCP socket, check name_connect permission for the port.
3816 */
3817 if (sksec->sclass == SECCLASS_TCP_SOCKET ||
3818 sksec->sclass == SECCLASS_DCCP_SOCKET) {
3819 struct common_audit_data ad;
3820 struct sockaddr_in *addr4 = NULL;
3821 struct sockaddr_in6 *addr6 = NULL;
3822 unsigned short snum;
3823 u32 sid, perm;
3824
3825 if (sk->sk_family == PF_INET) {
3826 addr4 = (struct sockaddr_in *)address;
3827 if (addrlen < sizeof(struct sockaddr_in))
3828 return -EINVAL;
3829 snum = ntohs(addr4->sin_port);
3830 } else {
3831 addr6 = (struct sockaddr_in6 *)address;
3832 if (addrlen < SIN6_LEN_RFC2133)
3833 return -EINVAL;
3834 snum = ntohs(addr6->sin6_port);
3835 }
3836
3837 err = sel_netport_sid(sk->sk_protocol, snum, &sid);
3838 if (err)
3839 goto out;
3840
3841 perm = (sksec->sclass == SECCLASS_TCP_SOCKET) ?
3842 TCP_SOCKET__NAME_CONNECT : DCCP_SOCKET__NAME_CONNECT;
3843
3844 COMMON_AUDIT_DATA_INIT(&ad, NET);
3845 ad.u.net.dport = htons(snum);
3846 ad.u.net.family = sk->sk_family;
3847 err = avc_has_perm(sksec->sid, sid, sksec->sclass, perm, &ad);
3848 if (err)
3849 goto out;
3850 }
3851
3852 err = selinux_netlbl_socket_connect(sk, address);
3853
3854 out:
3855 return err;
3856 }
3857
3858 static int selinux_socket_listen(struct socket *sock, int backlog)
3859 {
3860 return sock_has_perm(current, sock->sk, SOCKET__LISTEN);
3861 }
3862
3863 static int selinux_socket_accept(struct socket *sock, struct socket *newsock)
3864 {
3865 int err;
3866 struct inode_security_struct *isec;
3867 struct inode_security_struct *newisec;
3868
3869 err = sock_has_perm(current, sock->sk, SOCKET__ACCEPT);
3870 if (err)
3871 return err;
3872
3873 newisec = SOCK_INODE(newsock)->i_security;
3874
3875 isec = SOCK_INODE(sock)->i_security;
3876 newisec->sclass = isec->sclass;
3877 newisec->sid = isec->sid;
3878 newisec->initialized = 1;
3879
3880 return 0;
3881 }
3882
3883 static int selinux_socket_sendmsg(struct socket *sock, struct msghdr *msg,
3884 int size)
3885 {
3886 return sock_has_perm(current, sock->sk, SOCKET__WRITE);
3887 }
3888
3889 static int selinux_socket_recvmsg(struct socket *sock, struct msghdr *msg,
3890 int size, int flags)
3891 {
3892 return sock_has_perm(current, sock->sk, SOCKET__READ);
3893 }
3894
3895 static int selinux_socket_getsockname(struct socket *sock)
3896 {
3897 return sock_has_perm(current, sock->sk, SOCKET__GETATTR);
3898 }
3899
3900 static int selinux_socket_getpeername(struct socket *sock)
3901 {
3902 return sock_has_perm(current, sock->sk, SOCKET__GETATTR);
3903 }
3904
3905 static int selinux_socket_setsockopt(struct socket *sock, int level, int optname)
3906 {
3907 int err;
3908
3909 err = sock_has_perm(current, sock->sk, SOCKET__SETOPT);
3910 if (err)
3911 return err;
3912
3913 return selinux_netlbl_socket_setsockopt(sock, level, optname);
3914 }
3915
3916 static int selinux_socket_getsockopt(struct socket *sock, int level,
3917 int optname)
3918 {
3919 return sock_has_perm(current, sock->sk, SOCKET__GETOPT);
3920 }
3921
3922 static int selinux_socket_shutdown(struct socket *sock, int how)
3923 {
3924 return sock_has_perm(current, sock->sk, SOCKET__SHUTDOWN);
3925 }
3926
3927 static int selinux_socket_unix_stream_connect(struct socket *sock,
3928 struct socket *other,
3929 struct sock *newsk)
3930 {
3931 struct sk_security_struct *sksec_sock = sock->sk->sk_security;
3932 struct sk_security_struct *sksec_other = other->sk->sk_security;
3933 struct sk_security_struct *sksec_new = newsk->sk_security;
3934 struct common_audit_data ad;
3935 int err;
3936
3937 COMMON_AUDIT_DATA_INIT(&ad, NET);
3938 ad.u.net.sk = other->sk;
3939
3940 err = avc_has_perm(sksec_sock->sid, sksec_other->sid,
3941 sksec_other->sclass,
3942 UNIX_STREAM_SOCKET__CONNECTTO, &ad);
3943 if (err)
3944 return err;
3945
3946 /* server child socket */
3947 sksec_new->peer_sid = sksec_sock->sid;
3948 err = security_sid_mls_copy(sksec_other->sid, sksec_sock->sid,
3949 &sksec_new->sid);
3950 if (err)
3951 return err;
3952
3953 /* connecting socket */
3954 sksec_sock->peer_sid = sksec_new->sid;
3955
3956 return 0;
3957 }
3958
3959 static int selinux_socket_unix_may_send(struct socket *sock,
3960 struct socket *other)
3961 {
3962 struct sk_security_struct *ssec = sock->sk->sk_security;
3963 struct sk_security_struct *osec = other->sk->sk_security;
3964 struct common_audit_data ad;
3965
3966 COMMON_AUDIT_DATA_INIT(&ad, NET);
3967 ad.u.net.sk = other->sk;
3968
3969 return avc_has_perm(ssec->sid, osec->sid, osec->sclass, SOCKET__SENDTO,
3970 &ad);
3971 }
3972
3973 static int selinux_inet_sys_rcv_skb(int ifindex, char *addrp, u16 family,
3974 u32 peer_sid,
3975 struct common_audit_data *ad)
3976 {
3977 int err;
3978 u32 if_sid;
3979 u32 node_sid;
3980
3981 err = sel_netif_sid(ifindex, &if_sid);
3982 if (err)
3983 return err;
3984 err = avc_has_perm(peer_sid, if_sid,
3985 SECCLASS_NETIF, NETIF__INGRESS, ad);
3986 if (err)
3987 return err;
3988
3989 err = sel_netnode_sid(addrp, family, &node_sid);
3990 if (err)
3991 return err;
3992 return avc_has_perm(peer_sid, node_sid,
3993 SECCLASS_NODE, NODE__RECVFROM, ad);
3994 }
3995
3996 static int selinux_sock_rcv_skb_compat(struct sock *sk, struct sk_buff *skb,
3997 u16 family)
3998 {
3999 int err = 0;
4000 struct sk_security_struct *sksec = sk->sk_security;
4001 u32 peer_sid;
4002 u32 sk_sid = sksec->sid;
4003 struct common_audit_data ad;
4004 char *addrp;
4005
4006 COMMON_AUDIT_DATA_INIT(&ad, NET);
4007 ad.u.net.netif = skb->skb_iif;
4008 ad.u.net.family = family;
4009 err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL);
4010 if (err)
4011 return err;
4012
4013 if (selinux_secmark_enabled()) {
4014 err = avc_has_perm(sk_sid, skb->secmark, SECCLASS_PACKET,
4015 PACKET__RECV, &ad);
4016 if (err)
4017 return err;
4018 }
4019
4020 if (selinux_policycap_netpeer) {
4021 err = selinux_skb_peerlbl_sid(skb, family, &peer_sid);
4022 if (err)
4023 return err;
4024 err = avc_has_perm(sk_sid, peer_sid,
4025 SECCLASS_PEER, PEER__RECV, &ad);
4026 if (err)
4027 selinux_netlbl_err(skb, err, 0);
4028 } else {
4029 err = selinux_netlbl_sock_rcv_skb(sksec, skb, family, &ad);
4030 if (err)
4031 return err;
4032 err = selinux_xfrm_sock_rcv_skb(sksec->sid, skb, &ad);
4033 }
4034
4035 return err;
4036 }
4037
4038 static int selinux_socket_sock_rcv_skb(struct sock *sk, struct sk_buff *skb)
4039 {
4040 int err;
4041 struct sk_security_struct *sksec = sk->sk_security;
4042 u16 family = sk->sk_family;
4043 u32 sk_sid = sksec->sid;
4044 struct common_audit_data ad;
4045 char *addrp;
4046 u8 secmark_active;
4047 u8 peerlbl_active;
4048
4049 if (family != PF_INET && family != PF_INET6)
4050 return 0;
4051
4052 /* Handle mapped IPv4 packets arriving via IPv6 sockets */
4053 if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
4054 family = PF_INET;
4055
4056 /* If any sort of compatibility mode is enabled then handoff processing
4057 * to the selinux_sock_rcv_skb_compat() function to deal with the
4058 * special handling. We do this in an attempt to keep this function
4059 * as fast and as clean as possible. */
4060 if (!selinux_policycap_netpeer)
4061 return selinux_sock_rcv_skb_compat(sk, skb, family);
4062
4063 secmark_active = selinux_secmark_enabled();
4064 peerlbl_active = netlbl_enabled() || selinux_xfrm_enabled();
4065 if (!secmark_active && !peerlbl_active)
4066 return 0;
4067
4068 COMMON_AUDIT_DATA_INIT(&ad, NET);
4069 ad.u.net.netif = skb->skb_iif;
4070 ad.u.net.family = family;
4071 err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL);
4072 if (err)
4073 return err;
4074
4075 if (peerlbl_active) {
4076 u32 peer_sid;
4077
4078 err = selinux_skb_peerlbl_sid(skb, family, &peer_sid);
4079 if (err)
4080 return err;
4081 err = selinux_inet_sys_rcv_skb(skb->skb_iif, addrp, family,
4082 peer_sid, &ad);
4083 if (err) {
4084 selinux_netlbl_err(skb, err, 0);
4085 return err;
4086 }
4087 err = avc_has_perm(sk_sid, peer_sid, SECCLASS_PEER,
4088 PEER__RECV, &ad);
4089 if (err)
4090 selinux_netlbl_err(skb, err, 0);
4091 }
4092
4093 if (secmark_active) {
4094 err = avc_has_perm(sk_sid, skb->secmark, SECCLASS_PACKET,
4095 PACKET__RECV, &ad);
4096 if (err)
4097 return err;
4098 }
4099
4100 return err;
4101 }
4102
4103 static int selinux_socket_getpeersec_stream(struct socket *sock, char __user *optval,
4104 int __user *optlen, unsigned len)
4105 {
4106 int err = 0;
4107 char *scontext;
4108 u32 scontext_len;
4109 struct sk_security_struct *sksec = sock->sk->sk_security;
4110 u32 peer_sid = SECSID_NULL;
4111
4112 if (sksec->sclass == SECCLASS_UNIX_STREAM_SOCKET ||
4113 sksec->sclass == SECCLASS_TCP_SOCKET)
4114 peer_sid = sksec->peer_sid;
4115 if (peer_sid == SECSID_NULL)
4116 return -ENOPROTOOPT;
4117
4118 err = security_sid_to_context(peer_sid, &scontext, &scontext_len);
4119 if (err)
4120 return err;
4121
4122 if (scontext_len > len) {
4123 err = -ERANGE;
4124 goto out_len;
4125 }
4126
4127 if (copy_to_user(optval, scontext, scontext_len))
4128 err = -EFAULT;
4129
4130 out_len:
4131 if (put_user(scontext_len, optlen))
4132 err = -EFAULT;
4133 kfree(scontext);
4134 return err;
4135 }
4136
4137 static int selinux_socket_getpeersec_dgram(struct socket *sock, struct sk_buff *skb, u32 *secid)
4138 {
4139 u32 peer_secid = SECSID_NULL;
4140 u16 family;
4141
4142 if (skb && skb->protocol == htons(ETH_P_IP))
4143 family = PF_INET;
4144 else if (skb && skb->protocol == htons(ETH_P_IPV6))
4145 family = PF_INET6;
4146 else if (sock)
4147 family = sock->sk->sk_family;
4148 else
4149 goto out;
4150
4151 if (sock && family == PF_UNIX)
4152 selinux_inode_getsecid(SOCK_INODE(sock), &peer_secid);
4153 else if (skb)
4154 selinux_skb_peerlbl_sid(skb, family, &peer_secid);
4155
4156 out:
4157 *secid = peer_secid;
4158 if (peer_secid == SECSID_NULL)
4159 return -EINVAL;
4160 return 0;
4161 }
4162
4163 static int selinux_sk_alloc_security(struct sock *sk, int family, gfp_t priority)
4164 {
4165 struct sk_security_struct *sksec;
4166
4167 sksec = kzalloc(sizeof(*sksec), priority);
4168 if (!sksec)
4169 return -ENOMEM;
4170
4171 sksec->peer_sid = SECINITSID_UNLABELED;
4172 sksec->sid = SECINITSID_UNLABELED;
4173 selinux_netlbl_sk_security_reset(sksec);
4174 sk->sk_security = sksec;
4175
4176 return 0;
4177 }
4178
4179 static void selinux_sk_free_security(struct sock *sk)
4180 {
4181 struct sk_security_struct *sksec = sk->sk_security;
4182
4183 sk->sk_security = NULL;
4184 selinux_netlbl_sk_security_free(sksec);
4185 kfree(sksec);
4186 }
4187
4188 static void selinux_sk_clone_security(const struct sock *sk, struct sock *newsk)
4189 {
4190 struct sk_security_struct *sksec = sk->sk_security;
4191 struct sk_security_struct *newsksec = newsk->sk_security;
4192
4193 newsksec->sid = sksec->sid;
4194 newsksec->peer_sid = sksec->peer_sid;
4195 newsksec->sclass = sksec->sclass;
4196
4197 selinux_netlbl_sk_security_reset(newsksec);
4198 }
4199
4200 static void selinux_sk_getsecid(struct sock *sk, u32 *secid)
4201 {
4202 if (!sk)
4203 *secid = SECINITSID_ANY_SOCKET;
4204 else {
4205 struct sk_security_struct *sksec = sk->sk_security;
4206
4207 *secid = sksec->sid;
4208 }
4209 }
4210
4211 static void selinux_sock_graft(struct sock *sk, struct socket *parent)
4212 {
4213 struct inode_security_struct *isec = SOCK_INODE(parent)->i_security;
4214 struct sk_security_struct *sksec = sk->sk_security;
4215
4216 if (sk->sk_family == PF_INET || sk->sk_family == PF_INET6 ||
4217 sk->sk_family == PF_UNIX)
4218 isec->sid = sksec->sid;
4219 sksec->sclass = isec->sclass;
4220 }
4221
4222 static int selinux_inet_conn_request(struct sock *sk, struct sk_buff *skb,
4223 struct request_sock *req)
4224 {
4225 struct sk_security_struct *sksec = sk->sk_security;
4226 int err;
4227 u16 family = sk->sk_family;
4228 u32 newsid;
4229 u32 peersid;
4230
4231 /* handle mapped IPv4 packets arriving via IPv6 sockets */
4232 if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
4233 family = PF_INET;
4234
4235 err = selinux_skb_peerlbl_sid(skb, family, &peersid);
4236 if (err)
4237 return err;
4238 if (peersid == SECSID_NULL) {
4239 req->secid = sksec->sid;
4240 req->peer_secid = SECSID_NULL;
4241 } else {
4242 err = security_sid_mls_copy(sksec->sid, peersid, &newsid);
4243 if (err)
4244 return err;
4245 req->secid = newsid;
4246 req->peer_secid = peersid;
4247 }
4248
4249 return selinux_netlbl_inet_conn_request(req, family);
4250 }
4251
4252 static void selinux_inet_csk_clone(struct sock *newsk,
4253 const struct request_sock *req)
4254 {
4255 struct sk_security_struct *newsksec = newsk->sk_security;
4256
4257 newsksec->sid = req->secid;
4258 newsksec->peer_sid = req->peer_secid;
4259 /* NOTE: Ideally, we should also get the isec->sid for the
4260 new socket in sync, but we don't have the isec available yet.
4261 So we will wait until sock_graft to do it, by which
4262 time it will have been created and available. */
4263
4264 /* We don't need to take any sort of lock here as we are the only
4265 * thread with access to newsksec */
4266 selinux_netlbl_inet_csk_clone(newsk, req->rsk_ops->family);
4267 }
4268
4269 static void selinux_inet_conn_established(struct sock *sk, struct sk_buff *skb)
4270 {
4271 u16 family = sk->sk_family;
4272 struct sk_security_struct *sksec = sk->sk_security;
4273
4274 /* handle mapped IPv4 packets arriving via IPv6 sockets */
4275 if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
4276 family = PF_INET;
4277
4278 selinux_skb_peerlbl_sid(skb, family, &sksec->peer_sid);
4279 }
4280
4281 static void selinux_req_classify_flow(const struct request_sock *req,
4282 struct flowi *fl)
4283 {
4284 fl->secid = req->secid;
4285 }
4286
4287 static int selinux_tun_dev_create(void)
4288 {
4289 u32 sid = current_sid();
4290
4291 /* we aren't taking into account the "sockcreate" SID since the socket
4292 * that is being created here is not a socket in the traditional sense,
4293 * instead it is a private sock, accessible only to the kernel, and
4294 * representing a wide range of network traffic spanning multiple
4295 * connections unlike traditional sockets - check the TUN driver to
4296 * get a better understanding of why this socket is special */
4297
4298 return avc_has_perm(sid, sid, SECCLASS_TUN_SOCKET, TUN_SOCKET__CREATE,
4299 NULL);
4300 }
4301
4302 static void selinux_tun_dev_post_create(struct sock *sk)
4303 {
4304 struct sk_security_struct *sksec = sk->sk_security;
4305
4306 /* we don't currently perform any NetLabel based labeling here and it
4307 * isn't clear that we would want to do so anyway; while we could apply
4308 * labeling without the support of the TUN user the resulting labeled
4309 * traffic from the other end of the connection would almost certainly
4310 * cause confusion to the TUN user that had no idea network labeling
4311 * protocols were being used */
4312
4313 /* see the comments in selinux_tun_dev_create() about why we don't use
4314 * the sockcreate SID here */
4315
4316 sksec->sid = current_sid();
4317 sksec->sclass = SECCLASS_TUN_SOCKET;
4318 }
4319
4320 static int selinux_tun_dev_attach(struct sock *sk)
4321 {
4322 struct sk_security_struct *sksec = sk->sk_security;
4323 u32 sid = current_sid();
4324 int err;
4325
4326 err = avc_has_perm(sid, sksec->sid, SECCLASS_TUN_SOCKET,
4327 TUN_SOCKET__RELABELFROM, NULL);
4328 if (err)
4329 return err;
4330 err = avc_has_perm(sid, sid, SECCLASS_TUN_SOCKET,
4331 TUN_SOCKET__RELABELTO, NULL);
4332 if (err)
4333 return err;
4334
4335 sksec->sid = sid;
4336
4337 return 0;
4338 }
4339
4340 static int selinux_nlmsg_perm(struct sock *sk, struct sk_buff *skb)
4341 {
4342 int err = 0;
4343 u32 perm;
4344 struct nlmsghdr *nlh;
4345 struct sk_security_struct *sksec = sk->sk_security;
4346
4347 if (skb->len < NLMSG_SPACE(0)) {
4348 err = -EINVAL;
4349 goto out;
4350 }
4351 nlh = nlmsg_hdr(skb);
4352
4353 err = selinux_nlmsg_lookup(sksec->sclass, nlh->nlmsg_type, &perm);
4354 if (err) {
4355 if (err == -EINVAL) {
4356 audit_log(current->audit_context, GFP_KERNEL, AUDIT_SELINUX_ERR,
4357 "SELinux: unrecognized netlink message"
4358 " type=%hu for sclass=%hu\n",
4359 nlh->nlmsg_type, sksec->sclass);
4360 if (!selinux_enforcing || security_get_allow_unknown())
4361 err = 0;
4362 }
4363
4364 /* Ignore */
4365 if (err == -ENOENT)
4366 err = 0;
4367 goto out;
4368 }
4369
4370 err = sock_has_perm(current, sk, perm);
4371 out:
4372 return err;
4373 }
4374
4375 #ifdef CONFIG_NETFILTER
4376
4377 static unsigned int selinux_ip_forward(struct sk_buff *skb, int ifindex,
4378 u16 family)
4379 {
4380 int err;
4381 char *addrp;
4382 u32 peer_sid;
4383 struct common_audit_data ad;
4384 u8 secmark_active;
4385 u8 netlbl_active;
4386 u8 peerlbl_active;
4387
4388 if (!selinux_policycap_netpeer)
4389 return NF_ACCEPT;
4390
4391 secmark_active = selinux_secmark_enabled();
4392 netlbl_active = netlbl_enabled();
4393 peerlbl_active = netlbl_active || selinux_xfrm_enabled();
4394 if (!secmark_active && !peerlbl_active)
4395 return NF_ACCEPT;
4396
4397 if (selinux_skb_peerlbl_sid(skb, family, &peer_sid) != 0)
4398 return NF_DROP;
4399
4400 COMMON_AUDIT_DATA_INIT(&ad, NET);
4401 ad.u.net.netif = ifindex;
4402 ad.u.net.family = family;
4403 if (selinux_parse_skb(skb, &ad, &addrp, 1, NULL) != 0)
4404 return NF_DROP;
4405
4406 if (peerlbl_active) {
4407 err = selinux_inet_sys_rcv_skb(ifindex, addrp, family,
4408 peer_sid, &ad);
4409 if (err) {
4410 selinux_netlbl_err(skb, err, 1);
4411 return NF_DROP;
4412 }
4413 }
4414
4415 if (secmark_active)
4416 if (avc_has_perm(peer_sid, skb->secmark,
4417 SECCLASS_PACKET, PACKET__FORWARD_IN, &ad))
4418 return NF_DROP;
4419
4420 if (netlbl_active)
4421 /* we do this in the FORWARD path and not the POST_ROUTING
4422 * path because we want to make sure we apply the necessary
4423 * labeling before IPsec is applied so we can leverage AH
4424 * protection */
4425 if (selinux_netlbl_skbuff_setsid(skb, family, peer_sid) != 0)
4426 return NF_DROP;
4427
4428 return NF_ACCEPT;
4429 }
4430
4431 static unsigned int selinux_ipv4_forward(unsigned int hooknum,
4432 struct sk_buff *skb,
4433 const struct net_device *in,
4434 const struct net_device *out,
4435 int (*okfn)(struct sk_buff *))
4436 {
4437 return selinux_ip_forward(skb, in->ifindex, PF_INET);
4438 }
4439
4440 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
4441 static unsigned int selinux_ipv6_forward(unsigned int hooknum,
4442 struct sk_buff *skb,
4443 const struct net_device *in,
4444 const struct net_device *out,
4445 int (*okfn)(struct sk_buff *))
4446 {
4447 return selinux_ip_forward(skb, in->ifindex, PF_INET6);
4448 }
4449 #endif /* IPV6 */
4450
4451 static unsigned int selinux_ip_output(struct sk_buff *skb,
4452 u16 family)
4453 {
4454 u32 sid;
4455
4456 if (!netlbl_enabled())
4457 return NF_ACCEPT;
4458
4459 /* we do this in the LOCAL_OUT path and not the POST_ROUTING path
4460 * because we want to make sure we apply the necessary labeling
4461 * before IPsec is applied so we can leverage AH protection */
4462 if (skb->sk) {
4463 struct sk_security_struct *sksec = skb->sk->sk_security;
4464 sid = sksec->sid;
4465 } else
4466 sid = SECINITSID_KERNEL;
4467 if (selinux_netlbl_skbuff_setsid(skb, family, sid) != 0)
4468 return NF_DROP;
4469
4470 return NF_ACCEPT;
4471 }
4472
4473 static unsigned int selinux_ipv4_output(unsigned int hooknum,
4474 struct sk_buff *skb,
4475 const struct net_device *in,
4476 const struct net_device *out,
4477 int (*okfn)(struct sk_buff *))
4478 {
4479 return selinux_ip_output(skb, PF_INET);
4480 }
4481
4482 static unsigned int selinux_ip_postroute_compat(struct sk_buff *skb,
4483 int ifindex,
4484 u16 family)
4485 {
4486 struct sock *sk = skb->sk;
4487 struct sk_security_struct *sksec;
4488 struct common_audit_data ad;
4489 char *addrp;
4490 u8 proto;
4491
4492 if (sk == NULL)
4493 return NF_ACCEPT;
4494 sksec = sk->sk_security;
4495
4496 COMMON_AUDIT_DATA_INIT(&ad, NET);
4497 ad.u.net.netif = ifindex;
4498 ad.u.net.family = family;
4499 if (selinux_parse_skb(skb, &ad, &addrp, 0, &proto))
4500 return NF_DROP;
4501
4502 if (selinux_secmark_enabled())
4503 if (avc_has_perm(sksec->sid, skb->secmark,
4504 SECCLASS_PACKET, PACKET__SEND, &ad))
4505 return NF_DROP;
4506
4507 if (selinux_policycap_netpeer)
4508 if (selinux_xfrm_postroute_last(sksec->sid, skb, &ad, proto))
4509 return NF_DROP;
4510
4511 return NF_ACCEPT;
4512 }
4513
4514 static unsigned int selinux_ip_postroute(struct sk_buff *skb, int ifindex,
4515 u16 family)
4516 {
4517 u32 secmark_perm;
4518 u32 peer_sid;
4519 struct sock *sk;
4520 struct common_audit_data ad;
4521 char *addrp;
4522 u8 secmark_active;
4523 u8 peerlbl_active;
4524
4525 /* If any sort of compatibility mode is enabled then handoff processing
4526 * to the selinux_ip_postroute_compat() function to deal with the
4527 * special handling. We do this in an attempt to keep this function
4528 * as fast and as clean as possible. */
4529 if (!selinux_policycap_netpeer)
4530 return selinux_ip_postroute_compat(skb, ifindex, family);
4531 #ifdef CONFIG_XFRM
4532 /* If skb->dst->xfrm is non-NULL then the packet is undergoing an IPsec
4533 * packet transformation so allow the packet to pass without any checks
4534 * since we'll have another chance to perform access control checks
4535 * when the packet is on it's final way out.
4536 * NOTE: there appear to be some IPv6 multicast cases where skb->dst
4537 * is NULL, in this case go ahead and apply access control. */
4538 if (skb_dst(skb) != NULL && skb_dst(skb)->xfrm != NULL)
4539 return NF_ACCEPT;
4540 #endif
4541 secmark_active = selinux_secmark_enabled();
4542 peerlbl_active = netlbl_enabled() || selinux_xfrm_enabled();
4543 if (!secmark_active && !peerlbl_active)
4544 return NF_ACCEPT;
4545
4546 /* if the packet is being forwarded then get the peer label from the
4547 * packet itself; otherwise check to see if it is from a local
4548 * application or the kernel, if from an application get the peer label
4549 * from the sending socket, otherwise use the kernel's sid */
4550 sk = skb->sk;
4551 if (sk == NULL) {
4552 switch (family) {
4553 case PF_INET:
4554 if (IPCB(skb)->flags & IPSKB_FORWARDED)
4555 secmark_perm = PACKET__FORWARD_OUT;
4556 else
4557 secmark_perm = PACKET__SEND;
4558 break;
4559 case PF_INET6:
4560 if (IP6CB(skb)->flags & IP6SKB_FORWARDED)
4561 secmark_perm = PACKET__FORWARD_OUT;
4562 else
4563 secmark_perm = PACKET__SEND;
4564 break;
4565 default:
4566 return NF_DROP;
4567 }
4568 if (secmark_perm == PACKET__FORWARD_OUT) {
4569 if (selinux_skb_peerlbl_sid(skb, family, &peer_sid))
4570 return NF_DROP;
4571 } else
4572 peer_sid = SECINITSID_KERNEL;
4573 } else {
4574 struct sk_security_struct *sksec = sk->sk_security;
4575 peer_sid = sksec->sid;
4576 secmark_perm = PACKET__SEND;
4577 }
4578
4579 COMMON_AUDIT_DATA_INIT(&ad, NET);
4580 ad.u.net.netif = ifindex;
4581 ad.u.net.family = family;
4582 if (selinux_parse_skb(skb, &ad, &addrp, 0, NULL))
4583 return NF_DROP;
4584
4585 if (secmark_active)
4586 if (avc_has_perm(peer_sid, skb->secmark,
4587 SECCLASS_PACKET, secmark_perm, &ad))
4588 return NF_DROP;
4589
4590 if (peerlbl_active) {
4591 u32 if_sid;
4592 u32 node_sid;
4593
4594 if (sel_netif_sid(ifindex, &if_sid))
4595 return NF_DROP;
4596 if (avc_has_perm(peer_sid, if_sid,
4597 SECCLASS_NETIF, NETIF__EGRESS, &ad))
4598 return NF_DROP;
4599
4600 if (sel_netnode_sid(addrp, family, &node_sid))
4601 return NF_DROP;
4602 if (avc_has_perm(peer_sid, node_sid,
4603 SECCLASS_NODE, NODE__SENDTO, &ad))
4604 return NF_DROP;
4605 }
4606
4607 return NF_ACCEPT;
4608 }
4609
4610 static unsigned int selinux_ipv4_postroute(unsigned int hooknum,
4611 struct sk_buff *skb,
4612 const struct net_device *in,
4613 const struct net_device *out,
4614 int (*okfn)(struct sk_buff *))
4615 {
4616 return selinux_ip_postroute(skb, out->ifindex, PF_INET);
4617 }
4618
4619 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
4620 static unsigned int selinux_ipv6_postroute(unsigned int hooknum,
4621 struct sk_buff *skb,
4622 const struct net_device *in,
4623 const struct net_device *out,
4624 int (*okfn)(struct sk_buff *))
4625 {
4626 return selinux_ip_postroute(skb, out->ifindex, PF_INET6);
4627 }
4628 #endif /* IPV6 */
4629
4630 #endif /* CONFIG_NETFILTER */
4631
4632 static int selinux_netlink_send(struct sock *sk, struct sk_buff *skb)
4633 {
4634 int err;
4635
4636 err = cap_netlink_send(sk, skb);
4637 if (err)
4638 return err;
4639
4640 return selinux_nlmsg_perm(sk, skb);
4641 }
4642
4643 static int selinux_netlink_recv(struct sk_buff *skb, int capability)
4644 {
4645 int err;
4646 struct common_audit_data ad;
4647
4648 err = cap_netlink_recv(skb, capability);
4649 if (err)
4650 return err;
4651
4652 COMMON_AUDIT_DATA_INIT(&ad, CAP);
4653 ad.u.cap = capability;
4654
4655 return avc_has_perm(NETLINK_CB(skb).sid, NETLINK_CB(skb).sid,
4656 SECCLASS_CAPABILITY, CAP_TO_MASK(capability), &ad);
4657 }
4658
4659 static int ipc_alloc_security(struct task_struct *task,
4660 struct kern_ipc_perm *perm,
4661 u16 sclass)
4662 {
4663 struct ipc_security_struct *isec;
4664 u32 sid;
4665
4666 isec = kzalloc(sizeof(struct ipc_security_struct), GFP_KERNEL);
4667 if (!isec)
4668 return -ENOMEM;
4669
4670 sid = task_sid(task);
4671 isec->sclass = sclass;
4672 isec->sid = sid;
4673 perm->security = isec;
4674
4675 return 0;
4676 }
4677
4678 static void ipc_free_security(struct kern_ipc_perm *perm)
4679 {
4680 struct ipc_security_struct *isec = perm->security;
4681 perm->security = NULL;
4682 kfree(isec);
4683 }
4684
4685 static int msg_msg_alloc_security(struct msg_msg *msg)
4686 {
4687 struct msg_security_struct *msec;
4688
4689 msec = kzalloc(sizeof(struct msg_security_struct), GFP_KERNEL);
4690 if (!msec)
4691 return -ENOMEM;
4692
4693 msec->sid = SECINITSID_UNLABELED;
4694 msg->security = msec;
4695
4696 return 0;
4697 }
4698
4699 static void msg_msg_free_security(struct msg_msg *msg)
4700 {
4701 struct msg_security_struct *msec = msg->security;
4702
4703 msg->security = NULL;
4704 kfree(msec);
4705 }
4706
4707 static int ipc_has_perm(struct kern_ipc_perm *ipc_perms,
4708 u32 perms)
4709 {
4710 struct ipc_security_struct *isec;
4711 struct common_audit_data ad;
4712 u32 sid = current_sid();
4713
4714 isec = ipc_perms->security;
4715
4716 COMMON_AUDIT_DATA_INIT(&ad, IPC);
4717 ad.u.ipc_id = ipc_perms->key;
4718
4719 return avc_has_perm(sid, isec->sid, isec->sclass, perms, &ad);
4720 }
4721
4722 static int selinux_msg_msg_alloc_security(struct msg_msg *msg)
4723 {
4724 return msg_msg_alloc_security(msg);
4725 }
4726
4727 static void selinux_msg_msg_free_security(struct msg_msg *msg)
4728 {
4729 msg_msg_free_security(msg);
4730 }
4731
4732 /* message queue security operations */
4733 static int selinux_msg_queue_alloc_security(struct msg_queue *msq)
4734 {
4735 struct ipc_security_struct *isec;
4736 struct common_audit_data ad;
4737 u32 sid = current_sid();
4738 int rc;
4739
4740 rc = ipc_alloc_security(current, &msq->q_perm, SECCLASS_MSGQ);
4741 if (rc)
4742 return rc;
4743
4744 isec = msq->q_perm.security;
4745
4746 COMMON_AUDIT_DATA_INIT(&ad, IPC);
4747 ad.u.ipc_id = msq->q_perm.key;
4748
4749 rc = avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
4750 MSGQ__CREATE, &ad);
4751 if (rc) {
4752 ipc_free_security(&msq->q_perm);
4753 return rc;
4754 }
4755 return 0;
4756 }
4757
4758 static void selinux_msg_queue_free_security(struct msg_queue *msq)
4759 {
4760 ipc_free_security(&msq->q_perm);
4761 }
4762
4763 static int selinux_msg_queue_associate(struct msg_queue *msq, int msqflg)
4764 {
4765 struct ipc_security_struct *isec;
4766 struct common_audit_data ad;
4767 u32 sid = current_sid();
4768
4769 isec = msq->q_perm.security;
4770
4771 COMMON_AUDIT_DATA_INIT(&ad, IPC);
4772 ad.u.ipc_id = msq->q_perm.key;
4773
4774 return avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
4775 MSGQ__ASSOCIATE, &ad);
4776 }
4777
4778 static int selinux_msg_queue_msgctl(struct msg_queue *msq, int cmd)
4779 {
4780 int err;
4781 int perms;
4782
4783 switch (cmd) {
4784 case IPC_INFO:
4785 case MSG_INFO:
4786 /* No specific object, just general system-wide information. */
4787 return task_has_system(current, SYSTEM__IPC_INFO);
4788 case IPC_STAT:
4789 case MSG_STAT:
4790 perms = MSGQ__GETATTR | MSGQ__ASSOCIATE;
4791 break;
4792 case IPC_SET:
4793 perms = MSGQ__SETATTR;
4794 break;
4795 case IPC_RMID:
4796 perms = MSGQ__DESTROY;
4797 break;
4798 default:
4799 return 0;
4800 }
4801
4802 err = ipc_has_perm(&msq->q_perm, perms);
4803 return err;
4804 }
4805
4806 static int selinux_msg_queue_msgsnd(struct msg_queue *msq, struct msg_msg *msg, int msqflg)
4807 {
4808 struct ipc_security_struct *isec;
4809 struct msg_security_struct *msec;
4810 struct common_audit_data ad;
4811 u32 sid = current_sid();
4812 int rc;
4813
4814 isec = msq->q_perm.security;
4815 msec = msg->security;
4816
4817 /*
4818 * First time through, need to assign label to the message
4819 */
4820 if (msec->sid == SECINITSID_UNLABELED) {
4821 /*
4822 * Compute new sid based on current process and
4823 * message queue this message will be stored in
4824 */
4825 rc = security_transition_sid(sid, isec->sid, SECCLASS_MSG,
4826 &msec->sid);
4827 if (rc)
4828 return rc;
4829 }
4830
4831 COMMON_AUDIT_DATA_INIT(&ad, IPC);
4832 ad.u.ipc_id = msq->q_perm.key;
4833
4834 /* Can this process write to the queue? */
4835 rc = avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
4836 MSGQ__WRITE, &ad);
4837 if (!rc)
4838 /* Can this process send the message */
4839 rc = avc_has_perm(sid, msec->sid, SECCLASS_MSG,
4840 MSG__SEND, &ad);
4841 if (!rc)
4842 /* Can the message be put in the queue? */
4843 rc = avc_has_perm(msec->sid, isec->sid, SECCLASS_MSGQ,
4844 MSGQ__ENQUEUE, &ad);
4845
4846 return rc;
4847 }
4848
4849 static int selinux_msg_queue_msgrcv(struct msg_queue *msq, struct msg_msg *msg,
4850 struct task_struct *target,
4851 long type, int mode)
4852 {
4853 struct ipc_security_struct *isec;
4854 struct msg_security_struct *msec;
4855 struct common_audit_data ad;
4856 u32 sid = task_sid(target);
4857 int rc;
4858
4859 isec = msq->q_perm.security;
4860 msec = msg->security;
4861
4862 COMMON_AUDIT_DATA_INIT(&ad, IPC);
4863 ad.u.ipc_id = msq->q_perm.key;
4864
4865 rc = avc_has_perm(sid, isec->sid,
4866 SECCLASS_MSGQ, MSGQ__READ, &ad);
4867 if (!rc)
4868 rc = avc_has_perm(sid, msec->sid,
4869 SECCLASS_MSG, MSG__RECEIVE, &ad);
4870 return rc;
4871 }
4872
4873 /* Shared Memory security operations */
4874 static int selinux_shm_alloc_security(struct shmid_kernel *shp)
4875 {
4876 struct ipc_security_struct *isec;
4877 struct common_audit_data ad;
4878 u32 sid = current_sid();
4879 int rc;
4880
4881 rc = ipc_alloc_security(current, &shp->shm_perm, SECCLASS_SHM);
4882 if (rc)
4883 return rc;
4884
4885 isec = shp->shm_perm.security;
4886
4887 COMMON_AUDIT_DATA_INIT(&ad, IPC);
4888 ad.u.ipc_id = shp->shm_perm.key;
4889
4890 rc = avc_has_perm(sid, isec->sid, SECCLASS_SHM,
4891 SHM__CREATE, &ad);
4892 if (rc) {
4893 ipc_free_security(&shp->shm_perm);
4894 return rc;
4895 }
4896 return 0;
4897 }
4898
4899 static void selinux_shm_free_security(struct shmid_kernel *shp)
4900 {
4901 ipc_free_security(&shp->shm_perm);
4902 }
4903
4904 static int selinux_shm_associate(struct shmid_kernel *shp, int shmflg)
4905 {
4906 struct ipc_security_struct *isec;
4907 struct common_audit_data ad;
4908 u32 sid = current_sid();
4909
4910 isec = shp->shm_perm.security;
4911
4912 COMMON_AUDIT_DATA_INIT(&ad, IPC);
4913 ad.u.ipc_id = shp->shm_perm.key;
4914
4915 return avc_has_perm(sid, isec->sid, SECCLASS_SHM,
4916 SHM__ASSOCIATE, &ad);
4917 }
4918
4919 /* Note, at this point, shp is locked down */
4920 static int selinux_shm_shmctl(struct shmid_kernel *shp, int cmd)
4921 {
4922 int perms;
4923 int err;
4924
4925 switch (cmd) {
4926 case IPC_INFO:
4927 case SHM_INFO:
4928 /* No specific object, just general system-wide information. */
4929 return task_has_system(current, SYSTEM__IPC_INFO);
4930 case IPC_STAT:
4931 case SHM_STAT:
4932 perms = SHM__GETATTR | SHM__ASSOCIATE;
4933 break;
4934 case IPC_SET:
4935 perms = SHM__SETATTR;
4936 break;
4937 case SHM_LOCK:
4938 case SHM_UNLOCK:
4939 perms = SHM__LOCK;
4940 break;
4941 case IPC_RMID:
4942 perms = SHM__DESTROY;
4943 break;
4944 default:
4945 return 0;
4946 }
4947
4948 err = ipc_has_perm(&shp->shm_perm, perms);
4949 return err;
4950 }
4951
4952 static int selinux_shm_shmat(struct shmid_kernel *shp,
4953 char __user *shmaddr, int shmflg)
4954 {
4955 u32 perms;
4956
4957 if (shmflg & SHM_RDONLY)
4958 perms = SHM__READ;
4959 else
4960 perms = SHM__READ | SHM__WRITE;
4961
4962 return ipc_has_perm(&shp->shm_perm, perms);
4963 }
4964
4965 /* Semaphore security operations */
4966 static int selinux_sem_alloc_security(struct sem_array *sma)
4967 {
4968 struct ipc_security_struct *isec;
4969 struct common_audit_data ad;
4970 u32 sid = current_sid();
4971 int rc;
4972
4973 rc = ipc_alloc_security(current, &sma->sem_perm, SECCLASS_SEM);
4974 if (rc)
4975 return rc;
4976
4977 isec = sma->sem_perm.security;
4978
4979 COMMON_AUDIT_DATA_INIT(&ad, IPC);
4980 ad.u.ipc_id = sma->sem_perm.key;
4981
4982 rc = avc_has_perm(sid, isec->sid, SECCLASS_SEM,
4983 SEM__CREATE, &ad);
4984 if (rc) {
4985 ipc_free_security(&sma->sem_perm);
4986 return rc;
4987 }
4988 return 0;
4989 }
4990
4991 static void selinux_sem_free_security(struct sem_array *sma)
4992 {
4993 ipc_free_security(&sma->sem_perm);
4994 }
4995
4996 static int selinux_sem_associate(struct sem_array *sma, int semflg)
4997 {
4998 struct ipc_security_struct *isec;
4999 struct common_audit_data ad;
5000 u32 sid = current_sid();
5001
5002 isec = sma->sem_perm.security;
5003
5004 COMMON_AUDIT_DATA_INIT(&ad, IPC);
5005 ad.u.ipc_id = sma->sem_perm.key;
5006
5007 return avc_has_perm(sid, isec->sid, SECCLASS_SEM,
5008 SEM__ASSOCIATE, &ad);
5009 }
5010
5011 /* Note, at this point, sma is locked down */
5012 static int selinux_sem_semctl(struct sem_array *sma, int cmd)
5013 {
5014 int err;
5015 u32 perms;
5016
5017 switch (cmd) {
5018 case IPC_INFO:
5019 case SEM_INFO:
5020 /* No specific object, just general system-wide information. */
5021 return task_has_system(current, SYSTEM__IPC_INFO);
5022 case GETPID:
5023 case GETNCNT:
5024 case GETZCNT:
5025 perms = SEM__GETATTR;
5026 break;
5027 case GETVAL:
5028 case GETALL:
5029 perms = SEM__READ;
5030 break;
5031 case SETVAL:
5032 case SETALL:
5033 perms = SEM__WRITE;
5034 break;
5035 case IPC_RMID:
5036 perms = SEM__DESTROY;
5037 break;
5038 case IPC_SET:
5039 perms = SEM__SETATTR;
5040 break;
5041 case IPC_STAT:
5042 case SEM_STAT:
5043 perms = SEM__GETATTR | SEM__ASSOCIATE;
5044 break;
5045 default:
5046 return 0;
5047 }
5048
5049 err = ipc_has_perm(&sma->sem_perm, perms);
5050 return err;
5051 }
5052
5053 static int selinux_sem_semop(struct sem_array *sma,
5054 struct sembuf *sops, unsigned nsops, int alter)
5055 {
5056 u32 perms;
5057
5058 if (alter)
5059 perms = SEM__READ | SEM__WRITE;
5060 else
5061 perms = SEM__READ;
5062
5063 return ipc_has_perm(&sma->sem_perm, perms);
5064 }
5065
5066 static int selinux_ipc_permission(struct kern_ipc_perm *ipcp, short flag)
5067 {
5068 u32 av = 0;
5069
5070 av = 0;
5071 if (flag & S_IRUGO)
5072 av |= IPC__UNIX_READ;
5073 if (flag & S_IWUGO)
5074 av |= IPC__UNIX_WRITE;
5075
5076 if (av == 0)
5077 return 0;
5078
5079 return ipc_has_perm(ipcp, av);
5080 }
5081
5082 static void selinux_ipc_getsecid(struct kern_ipc_perm *ipcp, u32 *secid)
5083 {
5084 struct ipc_security_struct *isec = ipcp->security;
5085 *secid = isec->sid;
5086 }
5087
5088 static void selinux_d_instantiate(struct dentry *dentry, struct inode *inode)
5089 {
5090 if (inode)
5091 inode_doinit_with_dentry(inode, dentry);
5092 }
5093
5094 static int selinux_getprocattr(struct task_struct *p,
5095 char *name, char **value)
5096 {
5097 const struct task_security_struct *__tsec;
5098 u32 sid;
5099 int error;
5100 unsigned len;
5101
5102 if (current != p) {
5103 error = current_has_perm(p, PROCESS__GETATTR);
5104 if (error)
5105 return error;
5106 }
5107
5108 rcu_read_lock();
5109 __tsec = __task_cred(p)->security;
5110
5111 if (!strcmp(name, "current"))
5112 sid = __tsec->sid;
5113 else if (!strcmp(name, "prev"))
5114 sid = __tsec->osid;
5115 else if (!strcmp(name, "exec"))
5116 sid = __tsec->exec_sid;
5117 else if (!strcmp(name, "fscreate"))
5118 sid = __tsec->create_sid;
5119 else if (!strcmp(name, "keycreate"))
5120 sid = __tsec->keycreate_sid;
5121 else if (!strcmp(name, "sockcreate"))
5122 sid = __tsec->sockcreate_sid;
5123 else
5124 goto invalid;
5125 rcu_read_unlock();
5126
5127 if (!sid)
5128 return 0;
5129
5130 error = security_sid_to_context(sid, value, &len);
5131 if (error)
5132 return error;
5133 return len;
5134
5135 invalid:
5136 rcu_read_unlock();
5137 return -EINVAL;
5138 }
5139
5140 static int selinux_setprocattr(struct task_struct *p,
5141 char *name, void *value, size_t size)
5142 {
5143 struct task_security_struct *tsec;
5144 struct task_struct *tracer;
5145 struct cred *new;
5146 u32 sid = 0, ptsid;
5147 int error;
5148 char *str = value;
5149
5150 if (current != p) {
5151 /* SELinux only allows a process to change its own
5152 security attributes. */
5153 return -EACCES;
5154 }
5155
5156 /*
5157 * Basic control over ability to set these attributes at all.
5158 * current == p, but we'll pass them separately in case the
5159 * above restriction is ever removed.
5160 */
5161 if (!strcmp(name, "exec"))
5162 error = current_has_perm(p, PROCESS__SETEXEC);
5163 else if (!strcmp(name, "fscreate"))
5164 error = current_has_perm(p, PROCESS__SETFSCREATE);
5165 else if (!strcmp(name, "keycreate"))
5166 error = current_has_perm(p, PROCESS__SETKEYCREATE);
5167 else if (!strcmp(name, "sockcreate"))
5168 error = current_has_perm(p, PROCESS__SETSOCKCREATE);
5169 else if (!strcmp(name, "current"))
5170 error = current_has_perm(p, PROCESS__SETCURRENT);
5171 else
5172 error = -EINVAL;
5173 if (error)
5174 return error;
5175
5176 /* Obtain a SID for the context, if one was specified. */
5177 if (size && str[1] && str[1] != '\n') {
5178 if (str[size-1] == '\n') {
5179 str[size-1] = 0;
5180 size--;
5181 }
5182 error = security_context_to_sid(value, size, &sid);
5183 if (error == -EINVAL && !strcmp(name, "fscreate")) {
5184 if (!capable(CAP_MAC_ADMIN))
5185 return error;
5186 error = security_context_to_sid_force(value, size,
5187 &sid);
5188 }
5189 if (error)
5190 return error;
5191 }
5192
5193 new = prepare_creds();
5194 if (!new)
5195 return -ENOMEM;
5196
5197 /* Permission checking based on the specified context is
5198 performed during the actual operation (execve,
5199 open/mkdir/...), when we know the full context of the
5200 operation. See selinux_bprm_set_creds for the execve
5201 checks and may_create for the file creation checks. The
5202 operation will then fail if the context is not permitted. */
5203 tsec = new->security;
5204 if (!strcmp(name, "exec")) {
5205 tsec->exec_sid = sid;
5206 } else if (!strcmp(name, "fscreate")) {
5207 tsec->create_sid = sid;
5208 } else if (!strcmp(name, "keycreate")) {
5209 error = may_create_key(sid, p);
5210 if (error)
5211 goto abort_change;
5212 tsec->keycreate_sid = sid;
5213 } else if (!strcmp(name, "sockcreate")) {
5214 tsec->sockcreate_sid = sid;
5215 } else if (!strcmp(name, "current")) {
5216 error = -EINVAL;
5217 if (sid == 0)
5218 goto abort_change;
5219
5220 /* Only allow single threaded processes to change context */
5221 error = -EPERM;
5222 if (!current_is_single_threaded()) {
5223 error = security_bounded_transition(tsec->sid, sid);
5224 if (error)
5225 goto abort_change;
5226 }
5227
5228 /* Check permissions for the transition. */
5229 error = avc_has_perm(tsec->sid, sid, SECCLASS_PROCESS,
5230 PROCESS__DYNTRANSITION, NULL);
5231 if (error)
5232 goto abort_change;
5233
5234 /* Check for ptracing, and update the task SID if ok.
5235 Otherwise, leave SID unchanged and fail. */
5236 ptsid = 0;
5237 task_lock(p);
5238 tracer = tracehook_tracer_task(p);
5239 if (tracer)
5240 ptsid = task_sid(tracer);
5241 task_unlock(p);
5242
5243 if (tracer) {
5244 error = avc_has_perm(ptsid, sid, SECCLASS_PROCESS,
5245 PROCESS__PTRACE, NULL);
5246 if (error)
5247 goto abort_change;
5248 }
5249
5250 tsec->sid = sid;
5251 } else {
5252 error = -EINVAL;
5253 goto abort_change;
5254 }
5255
5256 commit_creds(new);
5257 return size;
5258
5259 abort_change:
5260 abort_creds(new);
5261 return error;
5262 }
5263
5264 static int selinux_secid_to_secctx(u32 secid, char **secdata, u32 *seclen)
5265 {
5266 return security_sid_to_context(secid, secdata, seclen);
5267 }
5268
5269 static int selinux_secctx_to_secid(const char *secdata, u32 seclen, u32 *secid)
5270 {
5271 return security_context_to_sid(secdata, seclen, secid);
5272 }
5273
5274 static void selinux_release_secctx(char *secdata, u32 seclen)
5275 {
5276 kfree(secdata);
5277 }
5278
5279 /*
5280 * called with inode->i_mutex locked
5281 */
5282 static int selinux_inode_notifysecctx(struct inode *inode, void *ctx, u32 ctxlen)
5283 {
5284 return selinux_inode_setsecurity(inode, XATTR_SELINUX_SUFFIX, ctx, ctxlen, 0);
5285 }
5286
5287 /*
5288 * called with inode->i_mutex locked
5289 */
5290 static int selinux_inode_setsecctx(struct dentry *dentry, void *ctx, u32 ctxlen)
5291 {
5292 return __vfs_setxattr_noperm(dentry, XATTR_NAME_SELINUX, ctx, ctxlen, 0);
5293 }
5294
5295 static int selinux_inode_getsecctx(struct inode *inode, void **ctx, u32 *ctxlen)
5296 {
5297 int len = 0;
5298 len = selinux_inode_getsecurity(inode, XATTR_SELINUX_SUFFIX,
5299 ctx, true);
5300 if (len < 0)
5301 return len;
5302 *ctxlen = len;
5303 return 0;
5304 }
5305 #ifdef CONFIG_KEYS
5306
5307 static int selinux_key_alloc(struct key *k, const struct cred *cred,
5308 unsigned long flags)
5309 {
5310 const struct task_security_struct *tsec;
5311 struct key_security_struct *ksec;
5312
5313 ksec = kzalloc(sizeof(struct key_security_struct), GFP_KERNEL);
5314 if (!ksec)
5315 return -ENOMEM;
5316
5317 tsec = cred->security;
5318 if (tsec->keycreate_sid)
5319 ksec->sid = tsec->keycreate_sid;
5320 else
5321 ksec->sid = tsec->sid;
5322
5323 k->security = ksec;
5324 return 0;
5325 }
5326
5327 static void selinux_key_free(struct key *k)
5328 {
5329 struct key_security_struct *ksec = k->security;
5330
5331 k->security = NULL;
5332 kfree(ksec);
5333 }
5334
5335 static int selinux_key_permission(key_ref_t key_ref,
5336 const struct cred *cred,
5337 key_perm_t perm)
5338 {
5339 struct key *key;
5340 struct key_security_struct *ksec;
5341 u32 sid;
5342
5343 /* if no specific permissions are requested, we skip the
5344 permission check. No serious, additional covert channels
5345 appear to be created. */
5346 if (perm == 0)
5347 return 0;
5348
5349 sid = cred_sid(cred);
5350
5351 key = key_ref_to_ptr(key_ref);
5352 ksec = key->security;
5353
5354 return avc_has_perm(sid, ksec->sid, SECCLASS_KEY, perm, NULL);
5355 }
5356
5357 static int selinux_key_getsecurity(struct key *key, char **_buffer)
5358 {
5359 struct key_security_struct *ksec = key->security;
5360 char *context = NULL;
5361 unsigned len;
5362 int rc;
5363
5364 rc = security_sid_to_context(ksec->sid, &context, &len);
5365 if (!rc)
5366 rc = len;
5367 *_buffer = context;
5368 return rc;
5369 }
5370
5371 #endif
5372
5373 static struct security_operations selinux_ops = {
5374 .name = "selinux",
5375
5376 .ptrace_access_check = selinux_ptrace_access_check,
5377 .ptrace_traceme = selinux_ptrace_traceme,
5378 .capget = selinux_capget,
5379 .capset = selinux_capset,
5380 .sysctl = selinux_sysctl,
5381 .capable = selinux_capable,
5382 .quotactl = selinux_quotactl,
5383 .quota_on = selinux_quota_on,
5384 .syslog = selinux_syslog,
5385 .vm_enough_memory = selinux_vm_enough_memory,
5386
5387 .netlink_send = selinux_netlink_send,
5388 .netlink_recv = selinux_netlink_recv,
5389
5390 .bprm_set_creds = selinux_bprm_set_creds,
5391 .bprm_committing_creds = selinux_bprm_committing_creds,
5392 .bprm_committed_creds = selinux_bprm_committed_creds,
5393 .bprm_secureexec = selinux_bprm_secureexec,
5394
5395 .sb_alloc_security = selinux_sb_alloc_security,
5396 .sb_free_security = selinux_sb_free_security,
5397 .sb_copy_data = selinux_sb_copy_data,
5398 .sb_kern_mount = selinux_sb_kern_mount,
5399 .sb_show_options = selinux_sb_show_options,
5400 .sb_statfs = selinux_sb_statfs,
5401 .sb_mount = selinux_mount,
5402 .sb_umount = selinux_umount,
5403 .sb_set_mnt_opts = selinux_set_mnt_opts,
5404 .sb_clone_mnt_opts = selinux_sb_clone_mnt_opts,
5405 .sb_parse_opts_str = selinux_parse_opts_str,
5406
5407
5408 .inode_alloc_security = selinux_inode_alloc_security,
5409 .inode_free_security = selinux_inode_free_security,
5410 .inode_init_security = selinux_inode_init_security,
5411 .inode_create = selinux_inode_create,
5412 .inode_link = selinux_inode_link,
5413 .inode_unlink = selinux_inode_unlink,
5414 .inode_symlink = selinux_inode_symlink,
5415 .inode_mkdir = selinux_inode_mkdir,
5416 .inode_rmdir = selinux_inode_rmdir,
5417 .inode_mknod = selinux_inode_mknod,
5418 .inode_rename = selinux_inode_rename,
5419 .inode_readlink = selinux_inode_readlink,
5420 .inode_follow_link = selinux_inode_follow_link,
5421 .inode_permission = selinux_inode_permission,
5422 .inode_setattr = selinux_inode_setattr,
5423 .inode_getattr = selinux_inode_getattr,
5424 .inode_setxattr = selinux_inode_setxattr,
5425 .inode_post_setxattr = selinux_inode_post_setxattr,
5426 .inode_getxattr = selinux_inode_getxattr,
5427 .inode_listxattr = selinux_inode_listxattr,
5428 .inode_removexattr = selinux_inode_removexattr,
5429 .inode_getsecurity = selinux_inode_getsecurity,
5430 .inode_setsecurity = selinux_inode_setsecurity,
5431 .inode_listsecurity = selinux_inode_listsecurity,
5432 .inode_getsecid = selinux_inode_getsecid,
5433
5434 .file_permission = selinux_file_permission,
5435 .file_alloc_security = selinux_file_alloc_security,
5436 .file_free_security = selinux_file_free_security,
5437 .file_ioctl = selinux_file_ioctl,
5438 .file_mmap = selinux_file_mmap,
5439 .file_mprotect = selinux_file_mprotect,
5440 .file_lock = selinux_file_lock,
5441 .file_fcntl = selinux_file_fcntl,
5442 .file_set_fowner = selinux_file_set_fowner,
5443 .file_send_sigiotask = selinux_file_send_sigiotask,
5444 .file_receive = selinux_file_receive,
5445
5446 .dentry_open = selinux_dentry_open,
5447
5448 .task_create = selinux_task_create,
5449 .cred_alloc_blank = selinux_cred_alloc_blank,
5450 .cred_free = selinux_cred_free,
5451 .cred_prepare = selinux_cred_prepare,
5452 .cred_transfer = selinux_cred_transfer,
5453 .kernel_act_as = selinux_kernel_act_as,
5454 .kernel_create_files_as = selinux_kernel_create_files_as,
5455 .kernel_module_request = selinux_kernel_module_request,
5456 .task_setpgid = selinux_task_setpgid,
5457 .task_getpgid = selinux_task_getpgid,
5458 .task_getsid = selinux_task_getsid,
5459 .task_getsecid = selinux_task_getsecid,
5460 .task_setnice = selinux_task_setnice,
5461 .task_setioprio = selinux_task_setioprio,
5462 .task_getioprio = selinux_task_getioprio,
5463 .task_setrlimit = selinux_task_setrlimit,
5464 .task_setscheduler = selinux_task_setscheduler,
5465 .task_getscheduler = selinux_task_getscheduler,
5466 .task_movememory = selinux_task_movememory,
5467 .task_kill = selinux_task_kill,
5468 .task_wait = selinux_task_wait,
5469 .task_to_inode = selinux_task_to_inode,
5470
5471 .ipc_permission = selinux_ipc_permission,
5472 .ipc_getsecid = selinux_ipc_getsecid,
5473
5474 .msg_msg_alloc_security = selinux_msg_msg_alloc_security,
5475 .msg_msg_free_security = selinux_msg_msg_free_security,
5476
5477 .msg_queue_alloc_security = selinux_msg_queue_alloc_security,
5478 .msg_queue_free_security = selinux_msg_queue_free_security,
5479 .msg_queue_associate = selinux_msg_queue_associate,
5480 .msg_queue_msgctl = selinux_msg_queue_msgctl,
5481 .msg_queue_msgsnd = selinux_msg_queue_msgsnd,
5482 .msg_queue_msgrcv = selinux_msg_queue_msgrcv,
5483
5484 .shm_alloc_security = selinux_shm_alloc_security,
5485 .shm_free_security = selinux_shm_free_security,
5486 .shm_associate = selinux_shm_associate,
5487 .shm_shmctl = selinux_shm_shmctl,
5488 .shm_shmat = selinux_shm_shmat,
5489
5490 .sem_alloc_security = selinux_sem_alloc_security,
5491 .sem_free_security = selinux_sem_free_security,
5492 .sem_associate = selinux_sem_associate,
5493 .sem_semctl = selinux_sem_semctl,
5494 .sem_semop = selinux_sem_semop,
5495
5496 .d_instantiate = selinux_d_instantiate,
5497
5498 .getprocattr = selinux_getprocattr,
5499 .setprocattr = selinux_setprocattr,
5500
5501 .secid_to_secctx = selinux_secid_to_secctx,
5502 .secctx_to_secid = selinux_secctx_to_secid,
5503 .release_secctx = selinux_release_secctx,
5504 .inode_notifysecctx = selinux_inode_notifysecctx,
5505 .inode_setsecctx = selinux_inode_setsecctx,
5506 .inode_getsecctx = selinux_inode_getsecctx,
5507
5508 .unix_stream_connect = selinux_socket_unix_stream_connect,
5509 .unix_may_send = selinux_socket_unix_may_send,
5510
5511 .socket_create = selinux_socket_create,
5512 .socket_post_create = selinux_socket_post_create,
5513 .socket_bind = selinux_socket_bind,
5514 .socket_connect = selinux_socket_connect,
5515 .socket_listen = selinux_socket_listen,
5516 .socket_accept = selinux_socket_accept,
5517 .socket_sendmsg = selinux_socket_sendmsg,
5518 .socket_recvmsg = selinux_socket_recvmsg,
5519 .socket_getsockname = selinux_socket_getsockname,
5520 .socket_getpeername = selinux_socket_getpeername,
5521 .socket_getsockopt = selinux_socket_getsockopt,
5522 .socket_setsockopt = selinux_socket_setsockopt,
5523 .socket_shutdown = selinux_socket_shutdown,
5524 .socket_sock_rcv_skb = selinux_socket_sock_rcv_skb,
5525 .socket_getpeersec_stream = selinux_socket_getpeersec_stream,
5526 .socket_getpeersec_dgram = selinux_socket_getpeersec_dgram,
5527 .sk_alloc_security = selinux_sk_alloc_security,
5528 .sk_free_security = selinux_sk_free_security,
5529 .sk_clone_security = selinux_sk_clone_security,
5530 .sk_getsecid = selinux_sk_getsecid,
5531 .sock_graft = selinux_sock_graft,
5532 .inet_conn_request = selinux_inet_conn_request,
5533 .inet_csk_clone = selinux_inet_csk_clone,
5534 .inet_conn_established = selinux_inet_conn_established,
5535 .req_classify_flow = selinux_req_classify_flow,
5536 .tun_dev_create = selinux_tun_dev_create,
5537 .tun_dev_post_create = selinux_tun_dev_post_create,
5538 .tun_dev_attach = selinux_tun_dev_attach,
5539
5540 #ifdef CONFIG_SECURITY_NETWORK_XFRM
5541 .xfrm_policy_alloc_security = selinux_xfrm_policy_alloc,
5542 .xfrm_policy_clone_security = selinux_xfrm_policy_clone,
5543 .xfrm_policy_free_security = selinux_xfrm_policy_free,
5544 .xfrm_policy_delete_security = selinux_xfrm_policy_delete,
5545 .xfrm_state_alloc_security = selinux_xfrm_state_alloc,
5546 .xfrm_state_free_security = selinux_xfrm_state_free,
5547 .xfrm_state_delete_security = selinux_xfrm_state_delete,
5548 .xfrm_policy_lookup = selinux_xfrm_policy_lookup,
5549 .xfrm_state_pol_flow_match = selinux_xfrm_state_pol_flow_match,
5550 .xfrm_decode_session = selinux_xfrm_decode_session,
5551 #endif
5552
5553 #ifdef CONFIG_KEYS
5554 .key_alloc = selinux_key_alloc,
5555 .key_free = selinux_key_free,
5556 .key_permission = selinux_key_permission,
5557 .key_getsecurity = selinux_key_getsecurity,
5558 #endif
5559
5560 #ifdef CONFIG_AUDIT
5561 .audit_rule_init = selinux_audit_rule_init,
5562 .audit_rule_known = selinux_audit_rule_known,
5563 .audit_rule_match = selinux_audit_rule_match,
5564 .audit_rule_free = selinux_audit_rule_free,
5565 #endif
5566 };
5567
5568 static __init int selinux_init(void)
5569 {
5570 if (!security_module_enable(&selinux_ops)) {
5571 selinux_enabled = 0;
5572 return 0;
5573 }
5574
5575 if (!selinux_enabled) {
5576 printk(KERN_INFO "SELinux: Disabled at boot.\n");
5577 return 0;
5578 }
5579
5580 printk(KERN_INFO "SELinux: Initializing.\n");
5581
5582 /* Set the security state for the initial task. */
5583 cred_init_security();
5584
5585 default_noexec = !(VM_DATA_DEFAULT_FLAGS & VM_EXEC);
5586
5587 sel_inode_cache = kmem_cache_create("selinux_inode_security",
5588 sizeof(struct inode_security_struct),
5589 0, SLAB_PANIC, NULL);
5590 avc_init();
5591
5592 if (register_security(&selinux_ops))
5593 panic("SELinux: Unable to register with kernel.\n");
5594
5595 if (selinux_enforcing)
5596 printk(KERN_DEBUG "SELinux: Starting in enforcing mode\n");
5597 else
5598 printk(KERN_DEBUG "SELinux: Starting in permissive mode\n");
5599
5600 return 0;
5601 }
5602
5603 static void delayed_superblock_init(struct super_block *sb, void *unused)
5604 {
5605 superblock_doinit(sb, NULL);
5606 }
5607
5608 void selinux_complete_init(void)
5609 {
5610 printk(KERN_DEBUG "SELinux: Completing initialization.\n");
5611
5612 /* Set up any superblocks initialized prior to the policy load. */
5613 printk(KERN_DEBUG "SELinux: Setting up existing superblocks.\n");
5614 iterate_supers(delayed_superblock_init, NULL);
5615 }
5616
5617 /* SELinux requires early initialization in order to label
5618 all processes and objects when they are created. */
5619 security_initcall(selinux_init);
5620
5621 #if defined(CONFIG_NETFILTER)
5622
5623 static struct nf_hook_ops selinux_ipv4_ops[] = {
5624 {
5625 .hook = selinux_ipv4_postroute,
5626 .owner = THIS_MODULE,
5627 .pf = PF_INET,
5628 .hooknum = NF_INET_POST_ROUTING,
5629 .priority = NF_IP_PRI_SELINUX_LAST,
5630 },
5631 {
5632 .hook = selinux_ipv4_forward,
5633 .owner = THIS_MODULE,
5634 .pf = PF_INET,
5635 .hooknum = NF_INET_FORWARD,
5636 .priority = NF_IP_PRI_SELINUX_FIRST,
5637 },
5638 {
5639 .hook = selinux_ipv4_output,
5640 .owner = THIS_MODULE,
5641 .pf = PF_INET,
5642 .hooknum = NF_INET_LOCAL_OUT,
5643 .priority = NF_IP_PRI_SELINUX_FIRST,
5644 }
5645 };
5646
5647 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
5648
5649 static struct nf_hook_ops selinux_ipv6_ops[] = {
5650 {
5651 .hook = selinux_ipv6_postroute,
5652 .owner = THIS_MODULE,
5653 .pf = PF_INET6,
5654 .hooknum = NF_INET_POST_ROUTING,
5655 .priority = NF_IP6_PRI_SELINUX_LAST,
5656 },
5657 {
5658 .hook = selinux_ipv6_forward,
5659 .owner = THIS_MODULE,
5660 .pf = PF_INET6,
5661 .hooknum = NF_INET_FORWARD,
5662 .priority = NF_IP6_PRI_SELINUX_FIRST,
5663 }
5664 };
5665
5666 #endif /* IPV6 */
5667
5668 static int __init selinux_nf_ip_init(void)
5669 {
5670 int err = 0;
5671
5672 if (!selinux_enabled)
5673 goto out;
5674
5675 printk(KERN_DEBUG "SELinux: Registering netfilter hooks\n");
5676
5677 err = nf_register_hooks(selinux_ipv4_ops, ARRAY_SIZE(selinux_ipv4_ops));
5678 if (err)
5679 panic("SELinux: nf_register_hooks for IPv4: error %d\n", err);
5680
5681 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
5682 err = nf_register_hooks(selinux_ipv6_ops, ARRAY_SIZE(selinux_ipv6_ops));
5683 if (err)
5684 panic("SELinux: nf_register_hooks for IPv6: error %d\n", err);
5685 #endif /* IPV6 */
5686
5687 out:
5688 return err;
5689 }
5690
5691 __initcall(selinux_nf_ip_init);
5692
5693 #ifdef CONFIG_SECURITY_SELINUX_DISABLE
5694 static void selinux_nf_ip_exit(void)
5695 {
5696 printk(KERN_DEBUG "SELinux: Unregistering netfilter hooks\n");
5697
5698 nf_unregister_hooks(selinux_ipv4_ops, ARRAY_SIZE(selinux_ipv4_ops));
5699 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
5700 nf_unregister_hooks(selinux_ipv6_ops, ARRAY_SIZE(selinux_ipv6_ops));
5701 #endif /* IPV6 */
5702 }
5703 #endif
5704
5705 #else /* CONFIG_NETFILTER */
5706
5707 #ifdef CONFIG_SECURITY_SELINUX_DISABLE
5708 #define selinux_nf_ip_exit()
5709 #endif
5710
5711 #endif /* CONFIG_NETFILTER */
5712
5713 #ifdef CONFIG_SECURITY_SELINUX_DISABLE
5714 static int selinux_disabled;
5715
5716 int selinux_disable(void)
5717 {
5718 extern void exit_sel_fs(void);
5719
5720 if (ss_initialized) {
5721 /* Not permitted after initial policy load. */
5722 return -EINVAL;
5723 }
5724
5725 if (selinux_disabled) {
5726 /* Only do this once. */
5727 return -EINVAL;
5728 }
5729
5730 printk(KERN_INFO "SELinux: Disabled at runtime.\n");
5731
5732 selinux_disabled = 1;
5733 selinux_enabled = 0;
5734
5735 reset_security_ops();
5736
5737 /* Try to destroy the avc node cache */
5738 avc_disable();
5739
5740 /* Unregister netfilter hooks. */
5741 selinux_nf_ip_exit();
5742
5743 /* Unregister selinuxfs. */
5744 exit_sel_fs();
5745
5746 return 0;
5747 }
5748 #endif
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