Merge branch 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel...
[GitHub/mt8127/android_kernel_alcatel_ttab.git] / security / selinux / hooks.c
1 /*
2 * NSA Security-Enhanced Linux (SELinux) security module
3 *
4 * This file contains the SELinux hook function implementations.
5 *
6 * Authors: Stephen Smalley, <sds@epoch.ncsc.mil>
7 * Chris Vance, <cvance@nai.com>
8 * Wayne Salamon, <wsalamon@nai.com>
9 * James Morris <jmorris@redhat.com>
10 *
11 * Copyright (C) 2001,2002 Networks Associates Technology, Inc.
12 * Copyright (C) 2003-2008 Red Hat, Inc., James Morris <jmorris@redhat.com>
13 * Eric Paris <eparis@redhat.com>
14 * Copyright (C) 2004-2005 Trusted Computer Solutions, Inc.
15 * <dgoeddel@trustedcs.com>
16 * Copyright (C) 2006, 2007, 2009 Hewlett-Packard Development Company, L.P.
17 * Paul Moore <paul@paul-moore.com>
18 * Copyright (C) 2007 Hitachi Software Engineering Co., Ltd.
19 * Yuichi Nakamura <ynakam@hitachisoft.jp>
20 *
21 * This program is free software; you can redistribute it and/or modify
22 * it under the terms of the GNU General Public License version 2,
23 * as published by the Free Software Foundation.
24 */
25
26 #include <linux/init.h>
27 #include <linux/kd.h>
28 #include <linux/kernel.h>
29 #include <linux/tracehook.h>
30 #include <linux/errno.h>
31 #include <linux/ext2_fs.h>
32 #include <linux/sched.h>
33 #include <linux/security.h>
34 #include <linux/xattr.h>
35 #include <linux/capability.h>
36 #include <linux/unistd.h>
37 #include <linux/mm.h>
38 #include <linux/mman.h>
39 #include <linux/slab.h>
40 #include <linux/pagemap.h>
41 #include <linux/proc_fs.h>
42 #include <linux/swap.h>
43 #include <linux/spinlock.h>
44 #include <linux/syscalls.h>
45 #include <linux/dcache.h>
46 #include <linux/file.h>
47 #include <linux/fdtable.h>
48 #include <linux/namei.h>
49 #include <linux/mount.h>
50 #include <linux/netfilter_ipv4.h>
51 #include <linux/netfilter_ipv6.h>
52 #include <linux/tty.h>
53 #include <net/icmp.h>
54 #include <net/ip.h> /* for local_port_range[] */
55 #include <net/tcp.h> /* struct or_callable used in sock_rcv_skb */
56 #include <net/net_namespace.h>
57 #include <net/netlabel.h>
58 #include <linux/uaccess.h>
59 #include <asm/ioctls.h>
60 #include <linux/atomic.h>
61 #include <linux/bitops.h>
62 #include <linux/interrupt.h>
63 #include <linux/netdevice.h> /* for network interface checks */
64 #include <linux/netlink.h>
65 #include <linux/tcp.h>
66 #include <linux/udp.h>
67 #include <linux/dccp.h>
68 #include <linux/quota.h>
69 #include <linux/un.h> /* for Unix socket types */
70 #include <net/af_unix.h> /* for Unix socket types */
71 #include <linux/parser.h>
72 #include <linux/nfs_mount.h>
73 #include <net/ipv6.h>
74 #include <linux/hugetlb.h>
75 #include <linux/personality.h>
76 #include <linux/audit.h>
77 #include <linux/string.h>
78 #include <linux/selinux.h>
79 #include <linux/mutex.h>
80 #include <linux/posix-timers.h>
81 #include <linux/syslog.h>
82 #include <linux/user_namespace.h>
83 #include <linux/export.h>
84
85 #include "avc.h"
86 #include "objsec.h"
87 #include "netif.h"
88 #include "netnode.h"
89 #include "netport.h"
90 #include "xfrm.h"
91 #include "netlabel.h"
92 #include "audit.h"
93 #include "avc_ss.h"
94
95 #define NUM_SEL_MNT_OPTS 5
96
97 extern struct security_operations *security_ops;
98
99 /* SECMARK reference count */
100 static atomic_t selinux_secmark_refcount = ATOMIC_INIT(0);
101
102 #ifdef CONFIG_SECURITY_SELINUX_DEVELOP
103 int selinux_enforcing;
104
105 static int __init enforcing_setup(char *str)
106 {
107 unsigned long enforcing;
108 if (!strict_strtoul(str, 0, &enforcing))
109 selinux_enforcing = enforcing ? 1 : 0;
110 return 1;
111 }
112 __setup("enforcing=", enforcing_setup);
113 #endif
114
115 #ifdef CONFIG_SECURITY_SELINUX_BOOTPARAM
116 int selinux_enabled = CONFIG_SECURITY_SELINUX_BOOTPARAM_VALUE;
117
118 static int __init selinux_enabled_setup(char *str)
119 {
120 unsigned long enabled;
121 if (!strict_strtoul(str, 0, &enabled))
122 selinux_enabled = enabled ? 1 : 0;
123 return 1;
124 }
125 __setup("selinux=", selinux_enabled_setup);
126 #else
127 int selinux_enabled = 1;
128 #endif
129
130 static struct kmem_cache *sel_inode_cache;
131
132 /**
133 * selinux_secmark_enabled - Check to see if SECMARK is currently enabled
134 *
135 * Description:
136 * This function checks the SECMARK reference counter to see if any SECMARK
137 * targets are currently configured, if the reference counter is greater than
138 * zero SECMARK is considered to be enabled. Returns true (1) if SECMARK is
139 * enabled, false (0) if SECMARK is disabled.
140 *
141 */
142 static int selinux_secmark_enabled(void)
143 {
144 return (atomic_read(&selinux_secmark_refcount) > 0);
145 }
146
147 /*
148 * initialise the security for the init task
149 */
150 static void cred_init_security(void)
151 {
152 struct cred *cred = (struct cred *) current->real_cred;
153 struct task_security_struct *tsec;
154
155 tsec = kzalloc(sizeof(struct task_security_struct), GFP_KERNEL);
156 if (!tsec)
157 panic("SELinux: Failed to initialize initial task.\n");
158
159 tsec->osid = tsec->sid = SECINITSID_KERNEL;
160 cred->security = tsec;
161 }
162
163 /*
164 * get the security ID of a set of credentials
165 */
166 static inline u32 cred_sid(const struct cred *cred)
167 {
168 const struct task_security_struct *tsec;
169
170 tsec = cred->security;
171 return tsec->sid;
172 }
173
174 /*
175 * get the objective security ID of a task
176 */
177 static inline u32 task_sid(const struct task_struct *task)
178 {
179 u32 sid;
180
181 rcu_read_lock();
182 sid = cred_sid(__task_cred(task));
183 rcu_read_unlock();
184 return sid;
185 }
186
187 /*
188 * get the subjective security ID of the current task
189 */
190 static inline u32 current_sid(void)
191 {
192 const struct task_security_struct *tsec = current_security();
193
194 return tsec->sid;
195 }
196
197 /* Allocate and free functions for each kind of security blob. */
198
199 static int inode_alloc_security(struct inode *inode)
200 {
201 struct inode_security_struct *isec;
202 u32 sid = current_sid();
203
204 isec = kmem_cache_zalloc(sel_inode_cache, GFP_NOFS);
205 if (!isec)
206 return -ENOMEM;
207
208 mutex_init(&isec->lock);
209 INIT_LIST_HEAD(&isec->list);
210 isec->inode = inode;
211 isec->sid = SECINITSID_UNLABELED;
212 isec->sclass = SECCLASS_FILE;
213 isec->task_sid = sid;
214 inode->i_security = isec;
215
216 return 0;
217 }
218
219 static void inode_free_security(struct inode *inode)
220 {
221 struct inode_security_struct *isec = inode->i_security;
222 struct superblock_security_struct *sbsec = inode->i_sb->s_security;
223
224 spin_lock(&sbsec->isec_lock);
225 if (!list_empty(&isec->list))
226 list_del_init(&isec->list);
227 spin_unlock(&sbsec->isec_lock);
228
229 inode->i_security = NULL;
230 kmem_cache_free(sel_inode_cache, isec);
231 }
232
233 static int file_alloc_security(struct file *file)
234 {
235 struct file_security_struct *fsec;
236 u32 sid = current_sid();
237
238 fsec = kzalloc(sizeof(struct file_security_struct), GFP_KERNEL);
239 if (!fsec)
240 return -ENOMEM;
241
242 fsec->sid = sid;
243 fsec->fown_sid = sid;
244 file->f_security = fsec;
245
246 return 0;
247 }
248
249 static void file_free_security(struct file *file)
250 {
251 struct file_security_struct *fsec = file->f_security;
252 file->f_security = NULL;
253 kfree(fsec);
254 }
255
256 static int superblock_alloc_security(struct super_block *sb)
257 {
258 struct superblock_security_struct *sbsec;
259
260 sbsec = kzalloc(sizeof(struct superblock_security_struct), GFP_KERNEL);
261 if (!sbsec)
262 return -ENOMEM;
263
264 mutex_init(&sbsec->lock);
265 INIT_LIST_HEAD(&sbsec->isec_head);
266 spin_lock_init(&sbsec->isec_lock);
267 sbsec->sb = sb;
268 sbsec->sid = SECINITSID_UNLABELED;
269 sbsec->def_sid = SECINITSID_FILE;
270 sbsec->mntpoint_sid = SECINITSID_UNLABELED;
271 sb->s_security = sbsec;
272
273 return 0;
274 }
275
276 static void superblock_free_security(struct super_block *sb)
277 {
278 struct superblock_security_struct *sbsec = sb->s_security;
279 sb->s_security = NULL;
280 kfree(sbsec);
281 }
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 return;
991 };
992 /* we need a comma before each option */
993 seq_putc(m, ',');
994 seq_puts(m, prefix);
995 if (has_comma)
996 seq_putc(m, '\"');
997 seq_puts(m, opts->mnt_opts[i]);
998 if (has_comma)
999 seq_putc(m, '\"');
1000 }
1001 }
1002
1003 static int selinux_sb_show_options(struct seq_file *m, struct super_block *sb)
1004 {
1005 struct security_mnt_opts opts;
1006 int rc;
1007
1008 rc = selinux_get_mnt_opts(sb, &opts);
1009 if (rc) {
1010 /* before policy load we may get EINVAL, don't show anything */
1011 if (rc == -EINVAL)
1012 rc = 0;
1013 return rc;
1014 }
1015
1016 selinux_write_opts(m, &opts);
1017
1018 security_free_mnt_opts(&opts);
1019
1020 return rc;
1021 }
1022
1023 static inline u16 inode_mode_to_security_class(umode_t mode)
1024 {
1025 switch (mode & S_IFMT) {
1026 case S_IFSOCK:
1027 return SECCLASS_SOCK_FILE;
1028 case S_IFLNK:
1029 return SECCLASS_LNK_FILE;
1030 case S_IFREG:
1031 return SECCLASS_FILE;
1032 case S_IFBLK:
1033 return SECCLASS_BLK_FILE;
1034 case S_IFDIR:
1035 return SECCLASS_DIR;
1036 case S_IFCHR:
1037 return SECCLASS_CHR_FILE;
1038 case S_IFIFO:
1039 return SECCLASS_FIFO_FILE;
1040
1041 }
1042
1043 return SECCLASS_FILE;
1044 }
1045
1046 static inline int default_protocol_stream(int protocol)
1047 {
1048 return (protocol == IPPROTO_IP || protocol == IPPROTO_TCP);
1049 }
1050
1051 static inline int default_protocol_dgram(int protocol)
1052 {
1053 return (protocol == IPPROTO_IP || protocol == IPPROTO_UDP);
1054 }
1055
1056 static inline u16 socket_type_to_security_class(int family, int type, int protocol)
1057 {
1058 switch (family) {
1059 case PF_UNIX:
1060 switch (type) {
1061 case SOCK_STREAM:
1062 case SOCK_SEQPACKET:
1063 return SECCLASS_UNIX_STREAM_SOCKET;
1064 case SOCK_DGRAM:
1065 return SECCLASS_UNIX_DGRAM_SOCKET;
1066 }
1067 break;
1068 case PF_INET:
1069 case PF_INET6:
1070 switch (type) {
1071 case SOCK_STREAM:
1072 if (default_protocol_stream(protocol))
1073 return SECCLASS_TCP_SOCKET;
1074 else
1075 return SECCLASS_RAWIP_SOCKET;
1076 case SOCK_DGRAM:
1077 if (default_protocol_dgram(protocol))
1078 return SECCLASS_UDP_SOCKET;
1079 else
1080 return SECCLASS_RAWIP_SOCKET;
1081 case SOCK_DCCP:
1082 return SECCLASS_DCCP_SOCKET;
1083 default:
1084 return SECCLASS_RAWIP_SOCKET;
1085 }
1086 break;
1087 case PF_NETLINK:
1088 switch (protocol) {
1089 case NETLINK_ROUTE:
1090 return SECCLASS_NETLINK_ROUTE_SOCKET;
1091 case NETLINK_FIREWALL:
1092 return SECCLASS_NETLINK_FIREWALL_SOCKET;
1093 case NETLINK_INET_DIAG:
1094 return SECCLASS_NETLINK_TCPDIAG_SOCKET;
1095 case NETLINK_NFLOG:
1096 return SECCLASS_NETLINK_NFLOG_SOCKET;
1097 case NETLINK_XFRM:
1098 return SECCLASS_NETLINK_XFRM_SOCKET;
1099 case NETLINK_SELINUX:
1100 return SECCLASS_NETLINK_SELINUX_SOCKET;
1101 case NETLINK_AUDIT:
1102 return SECCLASS_NETLINK_AUDIT_SOCKET;
1103 case NETLINK_IP6_FW:
1104 return SECCLASS_NETLINK_IP6FW_SOCKET;
1105 case NETLINK_DNRTMSG:
1106 return SECCLASS_NETLINK_DNRT_SOCKET;
1107 case NETLINK_KOBJECT_UEVENT:
1108 return SECCLASS_NETLINK_KOBJECT_UEVENT_SOCKET;
1109 default:
1110 return SECCLASS_NETLINK_SOCKET;
1111 }
1112 case PF_PACKET:
1113 return SECCLASS_PACKET_SOCKET;
1114 case PF_KEY:
1115 return SECCLASS_KEY_SOCKET;
1116 case PF_APPLETALK:
1117 return SECCLASS_APPLETALK_SOCKET;
1118 }
1119
1120 return SECCLASS_SOCKET;
1121 }
1122
1123 #ifdef CONFIG_PROC_FS
1124 static int selinux_proc_get_sid(struct dentry *dentry,
1125 u16 tclass,
1126 u32 *sid)
1127 {
1128 int rc;
1129 char *buffer, *path;
1130
1131 buffer = (char *)__get_free_page(GFP_KERNEL);
1132 if (!buffer)
1133 return -ENOMEM;
1134
1135 path = dentry_path_raw(dentry, buffer, PAGE_SIZE);
1136 if (IS_ERR(path))
1137 rc = PTR_ERR(path);
1138 else {
1139 /* each process gets a /proc/PID/ entry. Strip off the
1140 * PID part to get a valid selinux labeling.
1141 * e.g. /proc/1/net/rpc/nfs -> /net/rpc/nfs */
1142 while (path[1] >= '0' && path[1] <= '9') {
1143 path[1] = '/';
1144 path++;
1145 }
1146 rc = security_genfs_sid("proc", path, tclass, sid);
1147 }
1148 free_page((unsigned long)buffer);
1149 return rc;
1150 }
1151 #else
1152 static int selinux_proc_get_sid(struct dentry *dentry,
1153 u16 tclass,
1154 u32 *sid)
1155 {
1156 return -EINVAL;
1157 }
1158 #endif
1159
1160 /* The inode's security attributes must be initialized before first use. */
1161 static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dentry)
1162 {
1163 struct superblock_security_struct *sbsec = NULL;
1164 struct inode_security_struct *isec = inode->i_security;
1165 u32 sid;
1166 struct dentry *dentry;
1167 #define INITCONTEXTLEN 255
1168 char *context = NULL;
1169 unsigned len = 0;
1170 int rc = 0;
1171
1172 if (isec->initialized)
1173 goto out;
1174
1175 mutex_lock(&isec->lock);
1176 if (isec->initialized)
1177 goto out_unlock;
1178
1179 sbsec = inode->i_sb->s_security;
1180 if (!(sbsec->flags & SE_SBINITIALIZED)) {
1181 /* Defer initialization until selinux_complete_init,
1182 after the initial policy is loaded and the security
1183 server is ready to handle calls. */
1184 spin_lock(&sbsec->isec_lock);
1185 if (list_empty(&isec->list))
1186 list_add(&isec->list, &sbsec->isec_head);
1187 spin_unlock(&sbsec->isec_lock);
1188 goto out_unlock;
1189 }
1190
1191 switch (sbsec->behavior) {
1192 case SECURITY_FS_USE_XATTR:
1193 if (!inode->i_op->getxattr) {
1194 isec->sid = sbsec->def_sid;
1195 break;
1196 }
1197
1198 /* Need a dentry, since the xattr API requires one.
1199 Life would be simpler if we could just pass the inode. */
1200 if (opt_dentry) {
1201 /* Called from d_instantiate or d_splice_alias. */
1202 dentry = dget(opt_dentry);
1203 } else {
1204 /* Called from selinux_complete_init, try to find a dentry. */
1205 dentry = d_find_alias(inode);
1206 }
1207 if (!dentry) {
1208 /*
1209 * this is can be hit on boot when a file is accessed
1210 * before the policy is loaded. When we load policy we
1211 * may find inodes that have no dentry on the
1212 * sbsec->isec_head list. No reason to complain as these
1213 * will get fixed up the next time we go through
1214 * inode_doinit with a dentry, before these inodes could
1215 * be used again by userspace.
1216 */
1217 goto out_unlock;
1218 }
1219
1220 len = INITCONTEXTLEN;
1221 context = kmalloc(len+1, GFP_NOFS);
1222 if (!context) {
1223 rc = -ENOMEM;
1224 dput(dentry);
1225 goto out_unlock;
1226 }
1227 context[len] = '\0';
1228 rc = inode->i_op->getxattr(dentry, XATTR_NAME_SELINUX,
1229 context, len);
1230 if (rc == -ERANGE) {
1231 kfree(context);
1232
1233 /* Need a larger buffer. Query for the right size. */
1234 rc = inode->i_op->getxattr(dentry, XATTR_NAME_SELINUX,
1235 NULL, 0);
1236 if (rc < 0) {
1237 dput(dentry);
1238 goto out_unlock;
1239 }
1240 len = rc;
1241 context = kmalloc(len+1, GFP_NOFS);
1242 if (!context) {
1243 rc = -ENOMEM;
1244 dput(dentry);
1245 goto out_unlock;
1246 }
1247 context[len] = '\0';
1248 rc = inode->i_op->getxattr(dentry,
1249 XATTR_NAME_SELINUX,
1250 context, len);
1251 }
1252 dput(dentry);
1253 if (rc < 0) {
1254 if (rc != -ENODATA) {
1255 printk(KERN_WARNING "SELinux: %s: getxattr returned "
1256 "%d for dev=%s ino=%ld\n", __func__,
1257 -rc, inode->i_sb->s_id, inode->i_ino);
1258 kfree(context);
1259 goto out_unlock;
1260 }
1261 /* Map ENODATA to the default file SID */
1262 sid = sbsec->def_sid;
1263 rc = 0;
1264 } else {
1265 rc = security_context_to_sid_default(context, rc, &sid,
1266 sbsec->def_sid,
1267 GFP_NOFS);
1268 if (rc) {
1269 char *dev = inode->i_sb->s_id;
1270 unsigned long ino = inode->i_ino;
1271
1272 if (rc == -EINVAL) {
1273 if (printk_ratelimit())
1274 printk(KERN_NOTICE "SELinux: inode=%lu on dev=%s was found to have an invalid "
1275 "context=%s. This indicates you may need to relabel the inode or the "
1276 "filesystem in question.\n", ino, dev, context);
1277 } else {
1278 printk(KERN_WARNING "SELinux: %s: context_to_sid(%s) "
1279 "returned %d for dev=%s ino=%ld\n",
1280 __func__, context, -rc, dev, ino);
1281 }
1282 kfree(context);
1283 /* Leave with the unlabeled SID */
1284 rc = 0;
1285 break;
1286 }
1287 }
1288 kfree(context);
1289 isec->sid = sid;
1290 break;
1291 case SECURITY_FS_USE_TASK:
1292 isec->sid = isec->task_sid;
1293 break;
1294 case SECURITY_FS_USE_TRANS:
1295 /* Default to the fs SID. */
1296 isec->sid = sbsec->sid;
1297
1298 /* Try to obtain a transition SID. */
1299 isec->sclass = inode_mode_to_security_class(inode->i_mode);
1300 rc = security_transition_sid(isec->task_sid, sbsec->sid,
1301 isec->sclass, NULL, &sid);
1302 if (rc)
1303 goto out_unlock;
1304 isec->sid = sid;
1305 break;
1306 case SECURITY_FS_USE_MNTPOINT:
1307 isec->sid = sbsec->mntpoint_sid;
1308 break;
1309 default:
1310 /* Default to the fs superblock SID. */
1311 isec->sid = sbsec->sid;
1312
1313 if ((sbsec->flags & SE_SBPROC) && !S_ISLNK(inode->i_mode)) {
1314 if (opt_dentry) {
1315 isec->sclass = inode_mode_to_security_class(inode->i_mode);
1316 rc = selinux_proc_get_sid(opt_dentry,
1317 isec->sclass,
1318 &sid);
1319 if (rc)
1320 goto out_unlock;
1321 isec->sid = sid;
1322 }
1323 }
1324 break;
1325 }
1326
1327 isec->initialized = 1;
1328
1329 out_unlock:
1330 mutex_unlock(&isec->lock);
1331 out:
1332 if (isec->sclass == SECCLASS_FILE)
1333 isec->sclass = inode_mode_to_security_class(inode->i_mode);
1334 return rc;
1335 }
1336
1337 /* Convert a Linux signal to an access vector. */
1338 static inline u32 signal_to_av(int sig)
1339 {
1340 u32 perm = 0;
1341
1342 switch (sig) {
1343 case SIGCHLD:
1344 /* Commonly granted from child to parent. */
1345 perm = PROCESS__SIGCHLD;
1346 break;
1347 case SIGKILL:
1348 /* Cannot be caught or ignored */
1349 perm = PROCESS__SIGKILL;
1350 break;
1351 case SIGSTOP:
1352 /* Cannot be caught or ignored */
1353 perm = PROCESS__SIGSTOP;
1354 break;
1355 default:
1356 /* All other signals. */
1357 perm = PROCESS__SIGNAL;
1358 break;
1359 }
1360
1361 return perm;
1362 }
1363
1364 /*
1365 * Check permission between a pair of credentials
1366 * fork check, ptrace check, etc.
1367 */
1368 static int cred_has_perm(const struct cred *actor,
1369 const struct cred *target,
1370 u32 perms)
1371 {
1372 u32 asid = cred_sid(actor), tsid = cred_sid(target);
1373
1374 return avc_has_perm(asid, tsid, SECCLASS_PROCESS, perms, NULL);
1375 }
1376
1377 /*
1378 * Check permission between a pair of tasks, e.g. signal checks,
1379 * fork check, ptrace check, etc.
1380 * tsk1 is the actor and tsk2 is the target
1381 * - this uses the default subjective creds of tsk1
1382 */
1383 static int task_has_perm(const struct task_struct *tsk1,
1384 const struct task_struct *tsk2,
1385 u32 perms)
1386 {
1387 const struct task_security_struct *__tsec1, *__tsec2;
1388 u32 sid1, sid2;
1389
1390 rcu_read_lock();
1391 __tsec1 = __task_cred(tsk1)->security; sid1 = __tsec1->sid;
1392 __tsec2 = __task_cred(tsk2)->security; sid2 = __tsec2->sid;
1393 rcu_read_unlock();
1394 return avc_has_perm(sid1, sid2, SECCLASS_PROCESS, perms, NULL);
1395 }
1396
1397 /*
1398 * Check permission between current and another task, e.g. signal checks,
1399 * fork check, ptrace check, etc.
1400 * current is the actor and tsk2 is the target
1401 * - this uses current's subjective creds
1402 */
1403 static int current_has_perm(const struct task_struct *tsk,
1404 u32 perms)
1405 {
1406 u32 sid, tsid;
1407
1408 sid = current_sid();
1409 tsid = task_sid(tsk);
1410 return avc_has_perm(sid, tsid, SECCLASS_PROCESS, perms, NULL);
1411 }
1412
1413 #if CAP_LAST_CAP > 63
1414 #error Fix SELinux to handle capabilities > 63.
1415 #endif
1416
1417 /* Check whether a task is allowed to use a capability. */
1418 static int task_has_capability(struct task_struct *tsk,
1419 const struct cred *cred,
1420 int cap, int audit)
1421 {
1422 struct common_audit_data ad;
1423 struct av_decision avd;
1424 u16 sclass;
1425 u32 sid = cred_sid(cred);
1426 u32 av = CAP_TO_MASK(cap);
1427 int rc;
1428
1429 COMMON_AUDIT_DATA_INIT(&ad, CAP);
1430 ad.tsk = tsk;
1431 ad.u.cap = cap;
1432
1433 switch (CAP_TO_INDEX(cap)) {
1434 case 0:
1435 sclass = SECCLASS_CAPABILITY;
1436 break;
1437 case 1:
1438 sclass = SECCLASS_CAPABILITY2;
1439 break;
1440 default:
1441 printk(KERN_ERR
1442 "SELinux: out of range capability %d\n", cap);
1443 BUG();
1444 return -EINVAL;
1445 }
1446
1447 rc = avc_has_perm_noaudit(sid, sid, sclass, av, 0, &avd);
1448 if (audit == SECURITY_CAP_AUDIT) {
1449 int rc2 = avc_audit(sid, sid, sclass, av, &avd, rc, &ad, 0);
1450 if (rc2)
1451 return rc2;
1452 }
1453 return rc;
1454 }
1455
1456 /* Check whether a task is allowed to use a system operation. */
1457 static int task_has_system(struct task_struct *tsk,
1458 u32 perms)
1459 {
1460 u32 sid = task_sid(tsk);
1461
1462 return avc_has_perm(sid, SECINITSID_KERNEL,
1463 SECCLASS_SYSTEM, perms, NULL);
1464 }
1465
1466 /* Check whether a task has a particular permission to an inode.
1467 The 'adp' parameter is optional and allows other audit
1468 data to be passed (e.g. the dentry). */
1469 static int inode_has_perm(const struct cred *cred,
1470 struct inode *inode,
1471 u32 perms,
1472 struct common_audit_data *adp,
1473 unsigned flags)
1474 {
1475 struct inode_security_struct *isec;
1476 u32 sid;
1477
1478 validate_creds(cred);
1479
1480 if (unlikely(IS_PRIVATE(inode)))
1481 return 0;
1482
1483 sid = cred_sid(cred);
1484 isec = inode->i_security;
1485
1486 return avc_has_perm_flags(sid, isec->sid, isec->sclass, perms, adp, flags);
1487 }
1488
1489 static int inode_has_perm_noadp(const struct cred *cred,
1490 struct inode *inode,
1491 u32 perms,
1492 unsigned flags)
1493 {
1494 struct common_audit_data ad;
1495
1496 COMMON_AUDIT_DATA_INIT(&ad, INODE);
1497 ad.u.inode = inode;
1498 return inode_has_perm(cred, inode, perms, &ad, flags);
1499 }
1500
1501 /* Same as inode_has_perm, but pass explicit audit data containing
1502 the dentry to help the auditing code to more easily generate the
1503 pathname if needed. */
1504 static inline int dentry_has_perm(const struct cred *cred,
1505 struct dentry *dentry,
1506 u32 av)
1507 {
1508 struct inode *inode = dentry->d_inode;
1509 struct common_audit_data ad;
1510
1511 COMMON_AUDIT_DATA_INIT(&ad, DENTRY);
1512 ad.u.dentry = dentry;
1513 return inode_has_perm(cred, inode, av, &ad, 0);
1514 }
1515
1516 /* Same as inode_has_perm, but pass explicit audit data containing
1517 the path to help the auditing code to more easily generate the
1518 pathname if needed. */
1519 static inline int path_has_perm(const struct cred *cred,
1520 struct path *path,
1521 u32 av)
1522 {
1523 struct inode *inode = path->dentry->d_inode;
1524 struct common_audit_data ad;
1525
1526 COMMON_AUDIT_DATA_INIT(&ad, PATH);
1527 ad.u.path = *path;
1528 return inode_has_perm(cred, inode, av, &ad, 0);
1529 }
1530
1531 /* Check whether a task can use an open file descriptor to
1532 access an inode in a given way. Check access to the
1533 descriptor itself, and then use dentry_has_perm to
1534 check a particular permission to the file.
1535 Access to the descriptor is implicitly granted if it
1536 has the same SID as the process. If av is zero, then
1537 access to the file is not checked, e.g. for cases
1538 where only the descriptor is affected like seek. */
1539 static int file_has_perm(const struct cred *cred,
1540 struct file *file,
1541 u32 av)
1542 {
1543 struct file_security_struct *fsec = file->f_security;
1544 struct inode *inode = file->f_path.dentry->d_inode;
1545 struct common_audit_data ad;
1546 u32 sid = cred_sid(cred);
1547 int rc;
1548
1549 COMMON_AUDIT_DATA_INIT(&ad, PATH);
1550 ad.u.path = file->f_path;
1551
1552 if (sid != fsec->sid) {
1553 rc = avc_has_perm(sid, fsec->sid,
1554 SECCLASS_FD,
1555 FD__USE,
1556 &ad);
1557 if (rc)
1558 goto out;
1559 }
1560
1561 /* av is zero if only checking access to the descriptor. */
1562 rc = 0;
1563 if (av)
1564 rc = inode_has_perm(cred, inode, av, &ad, 0);
1565
1566 out:
1567 return rc;
1568 }
1569
1570 /* Check whether a task can create a file. */
1571 static int may_create(struct inode *dir,
1572 struct dentry *dentry,
1573 u16 tclass)
1574 {
1575 const struct task_security_struct *tsec = current_security();
1576 struct inode_security_struct *dsec;
1577 struct superblock_security_struct *sbsec;
1578 u32 sid, newsid;
1579 struct common_audit_data ad;
1580 int rc;
1581
1582 dsec = dir->i_security;
1583 sbsec = dir->i_sb->s_security;
1584
1585 sid = tsec->sid;
1586 newsid = tsec->create_sid;
1587
1588 COMMON_AUDIT_DATA_INIT(&ad, DENTRY);
1589 ad.u.dentry = dentry;
1590
1591 rc = avc_has_perm(sid, dsec->sid, SECCLASS_DIR,
1592 DIR__ADD_NAME | DIR__SEARCH,
1593 &ad);
1594 if (rc)
1595 return rc;
1596
1597 if (!newsid || !(sbsec->flags & SE_SBLABELSUPP)) {
1598 rc = security_transition_sid(sid, dsec->sid, tclass,
1599 &dentry->d_name, &newsid);
1600 if (rc)
1601 return rc;
1602 }
1603
1604 rc = avc_has_perm(sid, newsid, tclass, FILE__CREATE, &ad);
1605 if (rc)
1606 return rc;
1607
1608 return avc_has_perm(newsid, sbsec->sid,
1609 SECCLASS_FILESYSTEM,
1610 FILESYSTEM__ASSOCIATE, &ad);
1611 }
1612
1613 /* Check whether a task can create a key. */
1614 static int may_create_key(u32 ksid,
1615 struct task_struct *ctx)
1616 {
1617 u32 sid = task_sid(ctx);
1618
1619 return avc_has_perm(sid, ksid, SECCLASS_KEY, KEY__CREATE, NULL);
1620 }
1621
1622 #define MAY_LINK 0
1623 #define MAY_UNLINK 1
1624 #define MAY_RMDIR 2
1625
1626 /* Check whether a task can link, unlink, or rmdir a file/directory. */
1627 static int may_link(struct inode *dir,
1628 struct dentry *dentry,
1629 int kind)
1630
1631 {
1632 struct inode_security_struct *dsec, *isec;
1633 struct common_audit_data ad;
1634 u32 sid = current_sid();
1635 u32 av;
1636 int rc;
1637
1638 dsec = dir->i_security;
1639 isec = dentry->d_inode->i_security;
1640
1641 COMMON_AUDIT_DATA_INIT(&ad, DENTRY);
1642 ad.u.dentry = dentry;
1643
1644 av = DIR__SEARCH;
1645 av |= (kind ? DIR__REMOVE_NAME : DIR__ADD_NAME);
1646 rc = avc_has_perm(sid, dsec->sid, SECCLASS_DIR, av, &ad);
1647 if (rc)
1648 return rc;
1649
1650 switch (kind) {
1651 case MAY_LINK:
1652 av = FILE__LINK;
1653 break;
1654 case MAY_UNLINK:
1655 av = FILE__UNLINK;
1656 break;
1657 case MAY_RMDIR:
1658 av = DIR__RMDIR;
1659 break;
1660 default:
1661 printk(KERN_WARNING "SELinux: %s: unrecognized kind %d\n",
1662 __func__, kind);
1663 return 0;
1664 }
1665
1666 rc = avc_has_perm(sid, isec->sid, isec->sclass, av, &ad);
1667 return rc;
1668 }
1669
1670 static inline int may_rename(struct inode *old_dir,
1671 struct dentry *old_dentry,
1672 struct inode *new_dir,
1673 struct dentry *new_dentry)
1674 {
1675 struct inode_security_struct *old_dsec, *new_dsec, *old_isec, *new_isec;
1676 struct common_audit_data ad;
1677 u32 sid = current_sid();
1678 u32 av;
1679 int old_is_dir, new_is_dir;
1680 int rc;
1681
1682 old_dsec = old_dir->i_security;
1683 old_isec = old_dentry->d_inode->i_security;
1684 old_is_dir = S_ISDIR(old_dentry->d_inode->i_mode);
1685 new_dsec = new_dir->i_security;
1686
1687 COMMON_AUDIT_DATA_INIT(&ad, DENTRY);
1688
1689 ad.u.dentry = old_dentry;
1690 rc = avc_has_perm(sid, old_dsec->sid, SECCLASS_DIR,
1691 DIR__REMOVE_NAME | DIR__SEARCH, &ad);
1692 if (rc)
1693 return rc;
1694 rc = avc_has_perm(sid, old_isec->sid,
1695 old_isec->sclass, FILE__RENAME, &ad);
1696 if (rc)
1697 return rc;
1698 if (old_is_dir && new_dir != old_dir) {
1699 rc = avc_has_perm(sid, old_isec->sid,
1700 old_isec->sclass, DIR__REPARENT, &ad);
1701 if (rc)
1702 return rc;
1703 }
1704
1705 ad.u.dentry = new_dentry;
1706 av = DIR__ADD_NAME | DIR__SEARCH;
1707 if (new_dentry->d_inode)
1708 av |= DIR__REMOVE_NAME;
1709 rc = avc_has_perm(sid, new_dsec->sid, SECCLASS_DIR, av, &ad);
1710 if (rc)
1711 return rc;
1712 if (new_dentry->d_inode) {
1713 new_isec = new_dentry->d_inode->i_security;
1714 new_is_dir = S_ISDIR(new_dentry->d_inode->i_mode);
1715 rc = avc_has_perm(sid, new_isec->sid,
1716 new_isec->sclass,
1717 (new_is_dir ? DIR__RMDIR : FILE__UNLINK), &ad);
1718 if (rc)
1719 return rc;
1720 }
1721
1722 return 0;
1723 }
1724
1725 /* Check whether a task can perform a filesystem operation. */
1726 static int superblock_has_perm(const struct cred *cred,
1727 struct super_block *sb,
1728 u32 perms,
1729 struct common_audit_data *ad)
1730 {
1731 struct superblock_security_struct *sbsec;
1732 u32 sid = cred_sid(cred);
1733
1734 sbsec = sb->s_security;
1735 return avc_has_perm(sid, sbsec->sid, SECCLASS_FILESYSTEM, perms, ad);
1736 }
1737
1738 /* Convert a Linux mode and permission mask to an access vector. */
1739 static inline u32 file_mask_to_av(int mode, int mask)
1740 {
1741 u32 av = 0;
1742
1743 if ((mode & S_IFMT) != S_IFDIR) {
1744 if (mask & MAY_EXEC)
1745 av |= FILE__EXECUTE;
1746 if (mask & MAY_READ)
1747 av |= FILE__READ;
1748
1749 if (mask & MAY_APPEND)
1750 av |= FILE__APPEND;
1751 else if (mask & MAY_WRITE)
1752 av |= FILE__WRITE;
1753
1754 } else {
1755 if (mask & MAY_EXEC)
1756 av |= DIR__SEARCH;
1757 if (mask & MAY_WRITE)
1758 av |= DIR__WRITE;
1759 if (mask & MAY_READ)
1760 av |= DIR__READ;
1761 }
1762
1763 return av;
1764 }
1765
1766 /* Convert a Linux file to an access vector. */
1767 static inline u32 file_to_av(struct file *file)
1768 {
1769 u32 av = 0;
1770
1771 if (file->f_mode & FMODE_READ)
1772 av |= FILE__READ;
1773 if (file->f_mode & FMODE_WRITE) {
1774 if (file->f_flags & O_APPEND)
1775 av |= FILE__APPEND;
1776 else
1777 av |= FILE__WRITE;
1778 }
1779 if (!av) {
1780 /*
1781 * Special file opened with flags 3 for ioctl-only use.
1782 */
1783 av = FILE__IOCTL;
1784 }
1785
1786 return av;
1787 }
1788
1789 /*
1790 * Convert a file to an access vector and include the correct open
1791 * open permission.
1792 */
1793 static inline u32 open_file_to_av(struct file *file)
1794 {
1795 u32 av = file_to_av(file);
1796
1797 if (selinux_policycap_openperm)
1798 av |= FILE__OPEN;
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 struct user_namespace *ns, int cap, int audit)
1873 {
1874 int rc;
1875
1876 rc = cap_capable(tsk, cred, ns, cap, audit);
1877 if (rc)
1878 return rc;
1879
1880 return task_has_capability(tsk, cred, cap, audit);
1881 }
1882
1883 static int selinux_quotactl(int cmds, int type, int id, struct super_block *sb)
1884 {
1885 const struct cred *cred = current_cred();
1886 int rc = 0;
1887
1888 if (!sb)
1889 return 0;
1890
1891 switch (cmds) {
1892 case Q_SYNC:
1893 case Q_QUOTAON:
1894 case Q_QUOTAOFF:
1895 case Q_SETINFO:
1896 case Q_SETQUOTA:
1897 rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAMOD, NULL);
1898 break;
1899 case Q_GETFMT:
1900 case Q_GETINFO:
1901 case Q_GETQUOTA:
1902 rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAGET, NULL);
1903 break;
1904 default:
1905 rc = 0; /* let the kernel handle invalid cmds */
1906 break;
1907 }
1908 return rc;
1909 }
1910
1911 static int selinux_quota_on(struct dentry *dentry)
1912 {
1913 const struct cred *cred = current_cred();
1914
1915 return dentry_has_perm(cred, dentry, FILE__QUOTAON);
1916 }
1917
1918 static int selinux_syslog(int type)
1919 {
1920 int rc;
1921
1922 switch (type) {
1923 case SYSLOG_ACTION_READ_ALL: /* Read last kernel messages */
1924 case SYSLOG_ACTION_SIZE_BUFFER: /* Return size of the log buffer */
1925 rc = task_has_system(current, SYSTEM__SYSLOG_READ);
1926 break;
1927 case SYSLOG_ACTION_CONSOLE_OFF: /* Disable logging to console */
1928 case SYSLOG_ACTION_CONSOLE_ON: /* Enable logging to console */
1929 /* Set level of messages printed to console */
1930 case SYSLOG_ACTION_CONSOLE_LEVEL:
1931 rc = task_has_system(current, SYSTEM__SYSLOG_CONSOLE);
1932 break;
1933 case SYSLOG_ACTION_CLOSE: /* Close log */
1934 case SYSLOG_ACTION_OPEN: /* Open log */
1935 case SYSLOG_ACTION_READ: /* Read from log */
1936 case SYSLOG_ACTION_READ_CLEAR: /* Read/clear last kernel messages */
1937 case SYSLOG_ACTION_CLEAR: /* Clear ring buffer */
1938 default:
1939 rc = task_has_system(current, SYSTEM__SYSLOG_MOD);
1940 break;
1941 }
1942 return rc;
1943 }
1944
1945 /*
1946 * Check that a process has enough memory to allocate a new virtual
1947 * mapping. 0 means there is enough memory for the allocation to
1948 * succeed and -ENOMEM implies there is not.
1949 *
1950 * Do not audit the selinux permission check, as this is applied to all
1951 * processes that allocate mappings.
1952 */
1953 static int selinux_vm_enough_memory(struct mm_struct *mm, long pages)
1954 {
1955 int rc, cap_sys_admin = 0;
1956
1957 rc = selinux_capable(current, current_cred(),
1958 &init_user_ns, CAP_SYS_ADMIN,
1959 SECURITY_CAP_NOAUDIT);
1960 if (rc == 0)
1961 cap_sys_admin = 1;
1962
1963 return __vm_enough_memory(mm, pages, cap_sys_admin);
1964 }
1965
1966 /* binprm security operations */
1967
1968 static int selinux_bprm_set_creds(struct linux_binprm *bprm)
1969 {
1970 const struct task_security_struct *old_tsec;
1971 struct task_security_struct *new_tsec;
1972 struct inode_security_struct *isec;
1973 struct common_audit_data ad;
1974 struct inode *inode = bprm->file->f_path.dentry->d_inode;
1975 int rc;
1976
1977 rc = cap_bprm_set_creds(bprm);
1978 if (rc)
1979 return rc;
1980
1981 /* SELinux context only depends on initial program or script and not
1982 * the script interpreter */
1983 if (bprm->cred_prepared)
1984 return 0;
1985
1986 old_tsec = current_security();
1987 new_tsec = bprm->cred->security;
1988 isec = inode->i_security;
1989
1990 /* Default to the current task SID. */
1991 new_tsec->sid = old_tsec->sid;
1992 new_tsec->osid = old_tsec->sid;
1993
1994 /* Reset fs, key, and sock SIDs on execve. */
1995 new_tsec->create_sid = 0;
1996 new_tsec->keycreate_sid = 0;
1997 new_tsec->sockcreate_sid = 0;
1998
1999 if (old_tsec->exec_sid) {
2000 new_tsec->sid = old_tsec->exec_sid;
2001 /* Reset exec SID on execve. */
2002 new_tsec->exec_sid = 0;
2003 } else {
2004 /* Check for a default transition on this program. */
2005 rc = security_transition_sid(old_tsec->sid, isec->sid,
2006 SECCLASS_PROCESS, NULL,
2007 &new_tsec->sid);
2008 if (rc)
2009 return rc;
2010 }
2011
2012 COMMON_AUDIT_DATA_INIT(&ad, PATH);
2013 ad.u.path = bprm->file->f_path;
2014
2015 if (bprm->file->f_path.mnt->mnt_flags & MNT_NOSUID)
2016 new_tsec->sid = old_tsec->sid;
2017
2018 if (new_tsec->sid == old_tsec->sid) {
2019 rc = avc_has_perm(old_tsec->sid, isec->sid,
2020 SECCLASS_FILE, FILE__EXECUTE_NO_TRANS, &ad);
2021 if (rc)
2022 return rc;
2023 } else {
2024 /* Check permissions for the transition. */
2025 rc = avc_has_perm(old_tsec->sid, new_tsec->sid,
2026 SECCLASS_PROCESS, PROCESS__TRANSITION, &ad);
2027 if (rc)
2028 return rc;
2029
2030 rc = avc_has_perm(new_tsec->sid, isec->sid,
2031 SECCLASS_FILE, FILE__ENTRYPOINT, &ad);
2032 if (rc)
2033 return rc;
2034
2035 /* Check for shared state */
2036 if (bprm->unsafe & LSM_UNSAFE_SHARE) {
2037 rc = avc_has_perm(old_tsec->sid, new_tsec->sid,
2038 SECCLASS_PROCESS, PROCESS__SHARE,
2039 NULL);
2040 if (rc)
2041 return -EPERM;
2042 }
2043
2044 /* Make sure that anyone attempting to ptrace over a task that
2045 * changes its SID has the appropriate permit */
2046 if (bprm->unsafe &
2047 (LSM_UNSAFE_PTRACE | LSM_UNSAFE_PTRACE_CAP)) {
2048 struct task_struct *tracer;
2049 struct task_security_struct *sec;
2050 u32 ptsid = 0;
2051
2052 rcu_read_lock();
2053 tracer = ptrace_parent(current);
2054 if (likely(tracer != NULL)) {
2055 sec = __task_cred(tracer)->security;
2056 ptsid = sec->sid;
2057 }
2058 rcu_read_unlock();
2059
2060 if (ptsid != 0) {
2061 rc = avc_has_perm(ptsid, new_tsec->sid,
2062 SECCLASS_PROCESS,
2063 PROCESS__PTRACE, NULL);
2064 if (rc)
2065 return -EPERM;
2066 }
2067 }
2068
2069 /* Clear any possibly unsafe personality bits on exec: */
2070 bprm->per_clear |= PER_CLEAR_ON_SETID;
2071 }
2072
2073 return 0;
2074 }
2075
2076 static int selinux_bprm_secureexec(struct linux_binprm *bprm)
2077 {
2078 const struct task_security_struct *tsec = current_security();
2079 u32 sid, osid;
2080 int atsecure = 0;
2081
2082 sid = tsec->sid;
2083 osid = tsec->osid;
2084
2085 if (osid != sid) {
2086 /* Enable secure mode for SIDs transitions unless
2087 the noatsecure permission is granted between
2088 the two SIDs, i.e. ahp returns 0. */
2089 atsecure = avc_has_perm(osid, sid,
2090 SECCLASS_PROCESS,
2091 PROCESS__NOATSECURE, NULL);
2092 }
2093
2094 return (atsecure || cap_bprm_secureexec(bprm));
2095 }
2096
2097 /* Derived from fs/exec.c:flush_old_files. */
2098 static inline void flush_unauthorized_files(const struct cred *cred,
2099 struct files_struct *files)
2100 {
2101 struct common_audit_data ad;
2102 struct file *file, *devnull = NULL;
2103 struct tty_struct *tty;
2104 struct fdtable *fdt;
2105 long j = -1;
2106 int drop_tty = 0;
2107
2108 tty = get_current_tty();
2109 if (tty) {
2110 spin_lock(&tty_files_lock);
2111 if (!list_empty(&tty->tty_files)) {
2112 struct tty_file_private *file_priv;
2113 struct inode *inode;
2114
2115 /* Revalidate access to controlling tty.
2116 Use inode_has_perm on the tty inode directly rather
2117 than using file_has_perm, as this particular open
2118 file may belong to another process and we are only
2119 interested in the inode-based check here. */
2120 file_priv = list_first_entry(&tty->tty_files,
2121 struct tty_file_private, list);
2122 file = file_priv->file;
2123 inode = file->f_path.dentry->d_inode;
2124 if (inode_has_perm_noadp(cred, inode,
2125 FILE__READ | FILE__WRITE, 0)) {
2126 drop_tty = 1;
2127 }
2128 }
2129 spin_unlock(&tty_files_lock);
2130 tty_kref_put(tty);
2131 }
2132 /* Reset controlling tty. */
2133 if (drop_tty)
2134 no_tty();
2135
2136 /* Revalidate access to inherited open files. */
2137
2138 COMMON_AUDIT_DATA_INIT(&ad, INODE);
2139
2140 spin_lock(&files->file_lock);
2141 for (;;) {
2142 unsigned long set, i;
2143 int fd;
2144
2145 j++;
2146 i = j * __NFDBITS;
2147 fdt = files_fdtable(files);
2148 if (i >= fdt->max_fds)
2149 break;
2150 set = fdt->open_fds->fds_bits[j];
2151 if (!set)
2152 continue;
2153 spin_unlock(&files->file_lock);
2154 for ( ; set ; i++, set >>= 1) {
2155 if (set & 1) {
2156 file = fget(i);
2157 if (!file)
2158 continue;
2159 if (file_has_perm(cred,
2160 file,
2161 file_to_av(file))) {
2162 sys_close(i);
2163 fd = get_unused_fd();
2164 if (fd != i) {
2165 if (fd >= 0)
2166 put_unused_fd(fd);
2167 fput(file);
2168 continue;
2169 }
2170 if (devnull) {
2171 get_file(devnull);
2172 } else {
2173 devnull = dentry_open(
2174 dget(selinux_null),
2175 mntget(selinuxfs_mount),
2176 O_RDWR, cred);
2177 if (IS_ERR(devnull)) {
2178 devnull = NULL;
2179 put_unused_fd(fd);
2180 fput(file);
2181 continue;
2182 }
2183 }
2184 fd_install(fd, devnull);
2185 }
2186 fput(file);
2187 }
2188 }
2189 spin_lock(&files->file_lock);
2190
2191 }
2192 spin_unlock(&files->file_lock);
2193 }
2194
2195 /*
2196 * Prepare a process for imminent new credential changes due to exec
2197 */
2198 static void selinux_bprm_committing_creds(struct linux_binprm *bprm)
2199 {
2200 struct task_security_struct *new_tsec;
2201 struct rlimit *rlim, *initrlim;
2202 int rc, i;
2203
2204 new_tsec = bprm->cred->security;
2205 if (new_tsec->sid == new_tsec->osid)
2206 return;
2207
2208 /* Close files for which the new task SID is not authorized. */
2209 flush_unauthorized_files(bprm->cred, current->files);
2210
2211 /* Always clear parent death signal on SID transitions. */
2212 current->pdeath_signal = 0;
2213
2214 /* Check whether the new SID can inherit resource limits from the old
2215 * SID. If not, reset all soft limits to the lower of the current
2216 * task's hard limit and the init task's soft limit.
2217 *
2218 * Note that the setting of hard limits (even to lower them) can be
2219 * controlled by the setrlimit check. The inclusion of the init task's
2220 * soft limit into the computation is to avoid resetting soft limits
2221 * higher than the default soft limit for cases where the default is
2222 * lower than the hard limit, e.g. RLIMIT_CORE or RLIMIT_STACK.
2223 */
2224 rc = avc_has_perm(new_tsec->osid, new_tsec->sid, SECCLASS_PROCESS,
2225 PROCESS__RLIMITINH, NULL);
2226 if (rc) {
2227 /* protect against do_prlimit() */
2228 task_lock(current);
2229 for (i = 0; i < RLIM_NLIMITS; i++) {
2230 rlim = current->signal->rlim + i;
2231 initrlim = init_task.signal->rlim + i;
2232 rlim->rlim_cur = min(rlim->rlim_max, initrlim->rlim_cur);
2233 }
2234 task_unlock(current);
2235 update_rlimit_cpu(current, rlimit(RLIMIT_CPU));
2236 }
2237 }
2238
2239 /*
2240 * Clean up the process immediately after the installation of new credentials
2241 * due to exec
2242 */
2243 static void selinux_bprm_committed_creds(struct linux_binprm *bprm)
2244 {
2245 const struct task_security_struct *tsec = current_security();
2246 struct itimerval itimer;
2247 u32 osid, sid;
2248 int rc, i;
2249
2250 osid = tsec->osid;
2251 sid = tsec->sid;
2252
2253 if (sid == osid)
2254 return;
2255
2256 /* Check whether the new SID can inherit signal state from the old SID.
2257 * If not, clear itimers to avoid subsequent signal generation and
2258 * flush and unblock signals.
2259 *
2260 * This must occur _after_ the task SID has been updated so that any
2261 * kill done after the flush will be checked against the new SID.
2262 */
2263 rc = avc_has_perm(osid, sid, SECCLASS_PROCESS, PROCESS__SIGINH, NULL);
2264 if (rc) {
2265 memset(&itimer, 0, sizeof itimer);
2266 for (i = 0; i < 3; i++)
2267 do_setitimer(i, &itimer, NULL);
2268 spin_lock_irq(&current->sighand->siglock);
2269 if (!(current->signal->flags & SIGNAL_GROUP_EXIT)) {
2270 __flush_signals(current);
2271 flush_signal_handlers(current, 1);
2272 sigemptyset(&current->blocked);
2273 }
2274 spin_unlock_irq(&current->sighand->siglock);
2275 }
2276
2277 /* Wake up the parent if it is waiting so that it can recheck
2278 * wait permission to the new task SID. */
2279 read_lock(&tasklist_lock);
2280 __wake_up_parent(current, current->real_parent);
2281 read_unlock(&tasklist_lock);
2282 }
2283
2284 /* superblock security operations */
2285
2286 static int selinux_sb_alloc_security(struct super_block *sb)
2287 {
2288 return superblock_alloc_security(sb);
2289 }
2290
2291 static void selinux_sb_free_security(struct super_block *sb)
2292 {
2293 superblock_free_security(sb);
2294 }
2295
2296 static inline int match_prefix(char *prefix, int plen, char *option, int olen)
2297 {
2298 if (plen > olen)
2299 return 0;
2300
2301 return !memcmp(prefix, option, plen);
2302 }
2303
2304 static inline int selinux_option(char *option, int len)
2305 {
2306 return (match_prefix(CONTEXT_STR, sizeof(CONTEXT_STR)-1, option, len) ||
2307 match_prefix(FSCONTEXT_STR, sizeof(FSCONTEXT_STR)-1, option, len) ||
2308 match_prefix(DEFCONTEXT_STR, sizeof(DEFCONTEXT_STR)-1, option, len) ||
2309 match_prefix(ROOTCONTEXT_STR, sizeof(ROOTCONTEXT_STR)-1, option, len) ||
2310 match_prefix(LABELSUPP_STR, sizeof(LABELSUPP_STR)-1, option, len));
2311 }
2312
2313 static inline void take_option(char **to, char *from, int *first, int len)
2314 {
2315 if (!*first) {
2316 **to = ',';
2317 *to += 1;
2318 } else
2319 *first = 0;
2320 memcpy(*to, from, len);
2321 *to += len;
2322 }
2323
2324 static inline void take_selinux_option(char **to, char *from, int *first,
2325 int len)
2326 {
2327 int current_size = 0;
2328
2329 if (!*first) {
2330 **to = '|';
2331 *to += 1;
2332 } else
2333 *first = 0;
2334
2335 while (current_size < len) {
2336 if (*from != '"') {
2337 **to = *from;
2338 *to += 1;
2339 }
2340 from += 1;
2341 current_size += 1;
2342 }
2343 }
2344
2345 static int selinux_sb_copy_data(char *orig, char *copy)
2346 {
2347 int fnosec, fsec, rc = 0;
2348 char *in_save, *in_curr, *in_end;
2349 char *sec_curr, *nosec_save, *nosec;
2350 int open_quote = 0;
2351
2352 in_curr = orig;
2353 sec_curr = copy;
2354
2355 nosec = (char *)get_zeroed_page(GFP_KERNEL);
2356 if (!nosec) {
2357 rc = -ENOMEM;
2358 goto out;
2359 }
2360
2361 nosec_save = nosec;
2362 fnosec = fsec = 1;
2363 in_save = in_end = orig;
2364
2365 do {
2366 if (*in_end == '"')
2367 open_quote = !open_quote;
2368 if ((*in_end == ',' && open_quote == 0) ||
2369 *in_end == '\0') {
2370 int len = in_end - in_curr;
2371
2372 if (selinux_option(in_curr, len))
2373 take_selinux_option(&sec_curr, in_curr, &fsec, len);
2374 else
2375 take_option(&nosec, in_curr, &fnosec, len);
2376
2377 in_curr = in_end + 1;
2378 }
2379 } while (*in_end++);
2380
2381 strcpy(in_save, nosec_save);
2382 free_page((unsigned long)nosec_save);
2383 out:
2384 return rc;
2385 }
2386
2387 static int selinux_sb_remount(struct super_block *sb, void *data)
2388 {
2389 int rc, i, *flags;
2390 struct security_mnt_opts opts;
2391 char *secdata, **mount_options;
2392 struct superblock_security_struct *sbsec = sb->s_security;
2393
2394 if (!(sbsec->flags & SE_SBINITIALIZED))
2395 return 0;
2396
2397 if (!data)
2398 return 0;
2399
2400 if (sb->s_type->fs_flags & FS_BINARY_MOUNTDATA)
2401 return 0;
2402
2403 security_init_mnt_opts(&opts);
2404 secdata = alloc_secdata();
2405 if (!secdata)
2406 return -ENOMEM;
2407 rc = selinux_sb_copy_data(data, secdata);
2408 if (rc)
2409 goto out_free_secdata;
2410
2411 rc = selinux_parse_opts_str(secdata, &opts);
2412 if (rc)
2413 goto out_free_secdata;
2414
2415 mount_options = opts.mnt_opts;
2416 flags = opts.mnt_opts_flags;
2417
2418 for (i = 0; i < opts.num_mnt_opts; i++) {
2419 u32 sid;
2420 size_t len;
2421
2422 if (flags[i] == SE_SBLABELSUPP)
2423 continue;
2424 len = strlen(mount_options[i]);
2425 rc = security_context_to_sid(mount_options[i], len, &sid);
2426 if (rc) {
2427 printk(KERN_WARNING "SELinux: security_context_to_sid"
2428 "(%s) failed for (dev %s, type %s) errno=%d\n",
2429 mount_options[i], sb->s_id, sb->s_type->name, rc);
2430 goto out_free_opts;
2431 }
2432 rc = -EINVAL;
2433 switch (flags[i]) {
2434 case FSCONTEXT_MNT:
2435 if (bad_option(sbsec, FSCONTEXT_MNT, sbsec->sid, sid))
2436 goto out_bad_option;
2437 break;
2438 case CONTEXT_MNT:
2439 if (bad_option(sbsec, CONTEXT_MNT, sbsec->mntpoint_sid, sid))
2440 goto out_bad_option;
2441 break;
2442 case ROOTCONTEXT_MNT: {
2443 struct inode_security_struct *root_isec;
2444 root_isec = sb->s_root->d_inode->i_security;
2445
2446 if (bad_option(sbsec, ROOTCONTEXT_MNT, root_isec->sid, sid))
2447 goto out_bad_option;
2448 break;
2449 }
2450 case DEFCONTEXT_MNT:
2451 if (bad_option(sbsec, DEFCONTEXT_MNT, sbsec->def_sid, sid))
2452 goto out_bad_option;
2453 break;
2454 default:
2455 goto out_free_opts;
2456 }
2457 }
2458
2459 rc = 0;
2460 out_free_opts:
2461 security_free_mnt_opts(&opts);
2462 out_free_secdata:
2463 free_secdata(secdata);
2464 return rc;
2465 out_bad_option:
2466 printk(KERN_WARNING "SELinux: unable to change security options "
2467 "during remount (dev %s, type=%s)\n", sb->s_id,
2468 sb->s_type->name);
2469 goto out_free_opts;
2470 }
2471
2472 static int selinux_sb_kern_mount(struct super_block *sb, int flags, void *data)
2473 {
2474 const struct cred *cred = current_cred();
2475 struct common_audit_data ad;
2476 int rc;
2477
2478 rc = superblock_doinit(sb, data);
2479 if (rc)
2480 return rc;
2481
2482 /* Allow all mounts performed by the kernel */
2483 if (flags & MS_KERNMOUNT)
2484 return 0;
2485
2486 COMMON_AUDIT_DATA_INIT(&ad, DENTRY);
2487 ad.u.dentry = sb->s_root;
2488 return superblock_has_perm(cred, sb, FILESYSTEM__MOUNT, &ad);
2489 }
2490
2491 static int selinux_sb_statfs(struct dentry *dentry)
2492 {
2493 const struct cred *cred = current_cred();
2494 struct common_audit_data ad;
2495
2496 COMMON_AUDIT_DATA_INIT(&ad, DENTRY);
2497 ad.u.dentry = dentry->d_sb->s_root;
2498 return superblock_has_perm(cred, dentry->d_sb, FILESYSTEM__GETATTR, &ad);
2499 }
2500
2501 static int selinux_mount(char *dev_name,
2502 struct path *path,
2503 char *type,
2504 unsigned long flags,
2505 void *data)
2506 {
2507 const struct cred *cred = current_cred();
2508
2509 if (flags & MS_REMOUNT)
2510 return superblock_has_perm(cred, path->mnt->mnt_sb,
2511 FILESYSTEM__REMOUNT, NULL);
2512 else
2513 return path_has_perm(cred, path, FILE__MOUNTON);
2514 }
2515
2516 static int selinux_umount(struct vfsmount *mnt, int flags)
2517 {
2518 const struct cred *cred = current_cred();
2519
2520 return superblock_has_perm(cred, mnt->mnt_sb,
2521 FILESYSTEM__UNMOUNT, NULL);
2522 }
2523
2524 /* inode security operations */
2525
2526 static int selinux_inode_alloc_security(struct inode *inode)
2527 {
2528 return inode_alloc_security(inode);
2529 }
2530
2531 static void selinux_inode_free_security(struct inode *inode)
2532 {
2533 inode_free_security(inode);
2534 }
2535
2536 static int selinux_inode_init_security(struct inode *inode, struct inode *dir,
2537 const struct qstr *qstr, char **name,
2538 void **value, size_t *len)
2539 {
2540 const struct task_security_struct *tsec = current_security();
2541 struct inode_security_struct *dsec;
2542 struct superblock_security_struct *sbsec;
2543 u32 sid, newsid, clen;
2544 int rc;
2545 char *namep = NULL, *context;
2546
2547 dsec = dir->i_security;
2548 sbsec = dir->i_sb->s_security;
2549
2550 sid = tsec->sid;
2551 newsid = tsec->create_sid;
2552
2553 if ((sbsec->flags & SE_SBINITIALIZED) &&
2554 (sbsec->behavior == SECURITY_FS_USE_MNTPOINT))
2555 newsid = sbsec->mntpoint_sid;
2556 else if (!newsid || !(sbsec->flags & SE_SBLABELSUPP)) {
2557 rc = security_transition_sid(sid, dsec->sid,
2558 inode_mode_to_security_class(inode->i_mode),
2559 qstr, &newsid);
2560 if (rc) {
2561 printk(KERN_WARNING "%s: "
2562 "security_transition_sid failed, rc=%d (dev=%s "
2563 "ino=%ld)\n",
2564 __func__,
2565 -rc, inode->i_sb->s_id, inode->i_ino);
2566 return rc;
2567 }
2568 }
2569
2570 /* Possibly defer initialization to selinux_complete_init. */
2571 if (sbsec->flags & SE_SBINITIALIZED) {
2572 struct inode_security_struct *isec = inode->i_security;
2573 isec->sclass = inode_mode_to_security_class(inode->i_mode);
2574 isec->sid = newsid;
2575 isec->initialized = 1;
2576 }
2577
2578 if (!ss_initialized || !(sbsec->flags & SE_SBLABELSUPP))
2579 return -EOPNOTSUPP;
2580
2581 if (name) {
2582 namep = kstrdup(XATTR_SELINUX_SUFFIX, GFP_NOFS);
2583 if (!namep)
2584 return -ENOMEM;
2585 *name = namep;
2586 }
2587
2588 if (value && len) {
2589 rc = security_sid_to_context_force(newsid, &context, &clen);
2590 if (rc) {
2591 kfree(namep);
2592 return rc;
2593 }
2594 *value = context;
2595 *len = clen;
2596 }
2597
2598 return 0;
2599 }
2600
2601 static int selinux_inode_create(struct inode *dir, struct dentry *dentry, int mask)
2602 {
2603 return may_create(dir, dentry, SECCLASS_FILE);
2604 }
2605
2606 static int selinux_inode_link(struct dentry *old_dentry, struct inode *dir, struct dentry *new_dentry)
2607 {
2608 return may_link(dir, old_dentry, MAY_LINK);
2609 }
2610
2611 static int selinux_inode_unlink(struct inode *dir, struct dentry *dentry)
2612 {
2613 return may_link(dir, dentry, MAY_UNLINK);
2614 }
2615
2616 static int selinux_inode_symlink(struct inode *dir, struct dentry *dentry, const char *name)
2617 {
2618 return may_create(dir, dentry, SECCLASS_LNK_FILE);
2619 }
2620
2621 static int selinux_inode_mkdir(struct inode *dir, struct dentry *dentry, int mask)
2622 {
2623 return may_create(dir, dentry, SECCLASS_DIR);
2624 }
2625
2626 static int selinux_inode_rmdir(struct inode *dir, struct dentry *dentry)
2627 {
2628 return may_link(dir, dentry, MAY_RMDIR);
2629 }
2630
2631 static int selinux_inode_mknod(struct inode *dir, struct dentry *dentry, int mode, dev_t dev)
2632 {
2633 return may_create(dir, dentry, inode_mode_to_security_class(mode));
2634 }
2635
2636 static int selinux_inode_rename(struct inode *old_inode, struct dentry *old_dentry,
2637 struct inode *new_inode, struct dentry *new_dentry)
2638 {
2639 return may_rename(old_inode, old_dentry, new_inode, new_dentry);
2640 }
2641
2642 static int selinux_inode_readlink(struct dentry *dentry)
2643 {
2644 const struct cred *cred = current_cred();
2645
2646 return dentry_has_perm(cred, dentry, FILE__READ);
2647 }
2648
2649 static int selinux_inode_follow_link(struct dentry *dentry, struct nameidata *nameidata)
2650 {
2651 const struct cred *cred = current_cred();
2652
2653 return dentry_has_perm(cred, dentry, FILE__READ);
2654 }
2655
2656 static int selinux_inode_permission(struct inode *inode, int mask)
2657 {
2658 const struct cred *cred = current_cred();
2659 struct common_audit_data ad;
2660 u32 perms;
2661 bool from_access;
2662 unsigned flags = mask & MAY_NOT_BLOCK;
2663
2664 from_access = mask & MAY_ACCESS;
2665 mask &= (MAY_READ|MAY_WRITE|MAY_EXEC|MAY_APPEND);
2666
2667 /* No permission to check. Existence test. */
2668 if (!mask)
2669 return 0;
2670
2671 COMMON_AUDIT_DATA_INIT(&ad, INODE);
2672 ad.u.inode = inode;
2673
2674 if (from_access)
2675 ad.selinux_audit_data.auditdeny |= FILE__AUDIT_ACCESS;
2676
2677 perms = file_mask_to_av(inode->i_mode, mask);
2678
2679 return inode_has_perm(cred, inode, perms, &ad, flags);
2680 }
2681
2682 static int selinux_inode_setattr(struct dentry *dentry, struct iattr *iattr)
2683 {
2684 const struct cred *cred = current_cred();
2685 unsigned int ia_valid = iattr->ia_valid;
2686
2687 /* ATTR_FORCE is just used for ATTR_KILL_S[UG]ID. */
2688 if (ia_valid & ATTR_FORCE) {
2689 ia_valid &= ~(ATTR_KILL_SUID | ATTR_KILL_SGID | ATTR_MODE |
2690 ATTR_FORCE);
2691 if (!ia_valid)
2692 return 0;
2693 }
2694
2695 if (ia_valid & (ATTR_MODE | ATTR_UID | ATTR_GID |
2696 ATTR_ATIME_SET | ATTR_MTIME_SET | ATTR_TIMES_SET))
2697 return dentry_has_perm(cred, dentry, FILE__SETATTR);
2698
2699 return dentry_has_perm(cred, dentry, FILE__WRITE);
2700 }
2701
2702 static int selinux_inode_getattr(struct vfsmount *mnt, struct dentry *dentry)
2703 {
2704 const struct cred *cred = current_cred();
2705 struct path path;
2706
2707 path.dentry = dentry;
2708 path.mnt = mnt;
2709
2710 return path_has_perm(cred, &path, FILE__GETATTR);
2711 }
2712
2713 static int selinux_inode_setotherxattr(struct dentry *dentry, const char *name)
2714 {
2715 const struct cred *cred = current_cred();
2716
2717 if (!strncmp(name, XATTR_SECURITY_PREFIX,
2718 sizeof XATTR_SECURITY_PREFIX - 1)) {
2719 if (!strcmp(name, XATTR_NAME_CAPS)) {
2720 if (!capable(CAP_SETFCAP))
2721 return -EPERM;
2722 } else if (!capable(CAP_SYS_ADMIN)) {
2723 /* A different attribute in the security namespace.
2724 Restrict to administrator. */
2725 return -EPERM;
2726 }
2727 }
2728
2729 /* Not an attribute we recognize, so just check the
2730 ordinary setattr permission. */
2731 return dentry_has_perm(cred, dentry, FILE__SETATTR);
2732 }
2733
2734 static int selinux_inode_setxattr(struct dentry *dentry, const char *name,
2735 const void *value, size_t size, int flags)
2736 {
2737 struct inode *inode = dentry->d_inode;
2738 struct inode_security_struct *isec = inode->i_security;
2739 struct superblock_security_struct *sbsec;
2740 struct common_audit_data ad;
2741 u32 newsid, sid = current_sid();
2742 int rc = 0;
2743
2744 if (strcmp(name, XATTR_NAME_SELINUX))
2745 return selinux_inode_setotherxattr(dentry, name);
2746
2747 sbsec = inode->i_sb->s_security;
2748 if (!(sbsec->flags & SE_SBLABELSUPP))
2749 return -EOPNOTSUPP;
2750
2751 if (!inode_owner_or_capable(inode))
2752 return -EPERM;
2753
2754 COMMON_AUDIT_DATA_INIT(&ad, DENTRY);
2755 ad.u.dentry = dentry;
2756
2757 rc = avc_has_perm(sid, isec->sid, isec->sclass,
2758 FILE__RELABELFROM, &ad);
2759 if (rc)
2760 return rc;
2761
2762 rc = security_context_to_sid(value, size, &newsid);
2763 if (rc == -EINVAL) {
2764 if (!capable(CAP_MAC_ADMIN))
2765 return rc;
2766 rc = security_context_to_sid_force(value, size, &newsid);
2767 }
2768 if (rc)
2769 return rc;
2770
2771 rc = avc_has_perm(sid, newsid, isec->sclass,
2772 FILE__RELABELTO, &ad);
2773 if (rc)
2774 return rc;
2775
2776 rc = security_validate_transition(isec->sid, newsid, sid,
2777 isec->sclass);
2778 if (rc)
2779 return rc;
2780
2781 return avc_has_perm(newsid,
2782 sbsec->sid,
2783 SECCLASS_FILESYSTEM,
2784 FILESYSTEM__ASSOCIATE,
2785 &ad);
2786 }
2787
2788 static void selinux_inode_post_setxattr(struct dentry *dentry, const char *name,
2789 const void *value, size_t size,
2790 int flags)
2791 {
2792 struct inode *inode = dentry->d_inode;
2793 struct inode_security_struct *isec = inode->i_security;
2794 u32 newsid;
2795 int rc;
2796
2797 if (strcmp(name, XATTR_NAME_SELINUX)) {
2798 /* Not an attribute we recognize, so nothing to do. */
2799 return;
2800 }
2801
2802 rc = security_context_to_sid_force(value, size, &newsid);
2803 if (rc) {
2804 printk(KERN_ERR "SELinux: unable to map context to SID"
2805 "for (%s, %lu), rc=%d\n",
2806 inode->i_sb->s_id, inode->i_ino, -rc);
2807 return;
2808 }
2809
2810 isec->sid = newsid;
2811 return;
2812 }
2813
2814 static int selinux_inode_getxattr(struct dentry *dentry, const char *name)
2815 {
2816 const struct cred *cred = current_cred();
2817
2818 return dentry_has_perm(cred, dentry, FILE__GETATTR);
2819 }
2820
2821 static int selinux_inode_listxattr(struct dentry *dentry)
2822 {
2823 const struct cred *cred = current_cred();
2824
2825 return dentry_has_perm(cred, dentry, FILE__GETATTR);
2826 }
2827
2828 static int selinux_inode_removexattr(struct dentry *dentry, const char *name)
2829 {
2830 if (strcmp(name, XATTR_NAME_SELINUX))
2831 return selinux_inode_setotherxattr(dentry, name);
2832
2833 /* No one is allowed to remove a SELinux security label.
2834 You can change the label, but all data must be labeled. */
2835 return -EACCES;
2836 }
2837
2838 /*
2839 * Copy the inode security context value to the user.
2840 *
2841 * Permission check is handled by selinux_inode_getxattr hook.
2842 */
2843 static int selinux_inode_getsecurity(const struct inode *inode, const char *name, void **buffer, bool alloc)
2844 {
2845 u32 size;
2846 int error;
2847 char *context = NULL;
2848 struct inode_security_struct *isec = inode->i_security;
2849
2850 if (strcmp(name, XATTR_SELINUX_SUFFIX))
2851 return -EOPNOTSUPP;
2852
2853 /*
2854 * If the caller has CAP_MAC_ADMIN, then get the raw context
2855 * value even if it is not defined by current policy; otherwise,
2856 * use the in-core value under current policy.
2857 * Use the non-auditing forms of the permission checks since
2858 * getxattr may be called by unprivileged processes commonly
2859 * and lack of permission just means that we fall back to the
2860 * in-core context value, not a denial.
2861 */
2862 error = selinux_capable(current, current_cred(),
2863 &init_user_ns, CAP_MAC_ADMIN,
2864 SECURITY_CAP_NOAUDIT);
2865 if (!error)
2866 error = security_sid_to_context_force(isec->sid, &context,
2867 &size);
2868 else
2869 error = security_sid_to_context(isec->sid, &context, &size);
2870 if (error)
2871 return error;
2872 error = size;
2873 if (alloc) {
2874 *buffer = context;
2875 goto out_nofree;
2876 }
2877 kfree(context);
2878 out_nofree:
2879 return error;
2880 }
2881
2882 static int selinux_inode_setsecurity(struct inode *inode, const char *name,
2883 const void *value, size_t size, int flags)
2884 {
2885 struct inode_security_struct *isec = inode->i_security;
2886 u32 newsid;
2887 int rc;
2888
2889 if (strcmp(name, XATTR_SELINUX_SUFFIX))
2890 return -EOPNOTSUPP;
2891
2892 if (!value || !size)
2893 return -EACCES;
2894
2895 rc = security_context_to_sid((void *)value, size, &newsid);
2896 if (rc)
2897 return rc;
2898
2899 isec->sid = newsid;
2900 isec->initialized = 1;
2901 return 0;
2902 }
2903
2904 static int selinux_inode_listsecurity(struct inode *inode, char *buffer, size_t buffer_size)
2905 {
2906 const int len = sizeof(XATTR_NAME_SELINUX);
2907 if (buffer && len <= buffer_size)
2908 memcpy(buffer, XATTR_NAME_SELINUX, len);
2909 return len;
2910 }
2911
2912 static void selinux_inode_getsecid(const struct inode *inode, u32 *secid)
2913 {
2914 struct inode_security_struct *isec = inode->i_security;
2915 *secid = isec->sid;
2916 }
2917
2918 /* file security operations */
2919
2920 static int selinux_revalidate_file_permission(struct file *file, int mask)
2921 {
2922 const struct cred *cred = current_cred();
2923 struct inode *inode = file->f_path.dentry->d_inode;
2924
2925 /* file_mask_to_av won't add FILE__WRITE if MAY_APPEND is set */
2926 if ((file->f_flags & O_APPEND) && (mask & MAY_WRITE))
2927 mask |= MAY_APPEND;
2928
2929 return file_has_perm(cred, file,
2930 file_mask_to_av(inode->i_mode, mask));
2931 }
2932
2933 static int selinux_file_permission(struct file *file, int mask)
2934 {
2935 struct inode *inode = file->f_path.dentry->d_inode;
2936 struct file_security_struct *fsec = file->f_security;
2937 struct inode_security_struct *isec = inode->i_security;
2938 u32 sid = current_sid();
2939
2940 if (!mask)
2941 /* No permission to check. Existence test. */
2942 return 0;
2943
2944 if (sid == fsec->sid && fsec->isid == isec->sid &&
2945 fsec->pseqno == avc_policy_seqno())
2946 /* No change since dentry_open check. */
2947 return 0;
2948
2949 return selinux_revalidate_file_permission(file, mask);
2950 }
2951
2952 static int selinux_file_alloc_security(struct file *file)
2953 {
2954 return file_alloc_security(file);
2955 }
2956
2957 static void selinux_file_free_security(struct file *file)
2958 {
2959 file_free_security(file);
2960 }
2961
2962 static int selinux_file_ioctl(struct file *file, unsigned int cmd,
2963 unsigned long arg)
2964 {
2965 const struct cred *cred = current_cred();
2966 int error = 0;
2967
2968 switch (cmd) {
2969 case FIONREAD:
2970 /* fall through */
2971 case FIBMAP:
2972 /* fall through */
2973 case FIGETBSZ:
2974 /* fall through */
2975 case EXT2_IOC_GETFLAGS:
2976 /* fall through */
2977 case EXT2_IOC_GETVERSION:
2978 error = file_has_perm(cred, file, FILE__GETATTR);
2979 break;
2980
2981 case EXT2_IOC_SETFLAGS:
2982 /* fall through */
2983 case EXT2_IOC_SETVERSION:
2984 error = file_has_perm(cred, file, FILE__SETATTR);
2985 break;
2986
2987 /* sys_ioctl() checks */
2988 case FIONBIO:
2989 /* fall through */
2990 case FIOASYNC:
2991 error = file_has_perm(cred, file, 0);
2992 break;
2993
2994 case KDSKBENT:
2995 case KDSKBSENT:
2996 error = task_has_capability(current, cred, CAP_SYS_TTY_CONFIG,
2997 SECURITY_CAP_AUDIT);
2998 break;
2999
3000 /* default case assumes that the command will go
3001 * to the file's ioctl() function.
3002 */
3003 default:
3004 error = file_has_perm(cred, file, FILE__IOCTL);
3005 }
3006 return error;
3007 }
3008
3009 static int default_noexec;
3010
3011 static int file_map_prot_check(struct file *file, unsigned long prot, int shared)
3012 {
3013 const struct cred *cred = current_cred();
3014 int rc = 0;
3015
3016 if (default_noexec &&
3017 (prot & PROT_EXEC) && (!file || (!shared && (prot & PROT_WRITE)))) {
3018 /*
3019 * We are making executable an anonymous mapping or a
3020 * private file mapping that will also be writable.
3021 * This has an additional check.
3022 */
3023 rc = cred_has_perm(cred, cred, PROCESS__EXECMEM);
3024 if (rc)
3025 goto error;
3026 }
3027
3028 if (file) {
3029 /* read access is always possible with a mapping */
3030 u32 av = FILE__READ;
3031
3032 /* write access only matters if the mapping is shared */
3033 if (shared && (prot & PROT_WRITE))
3034 av |= FILE__WRITE;
3035
3036 if (prot & PROT_EXEC)
3037 av |= FILE__EXECUTE;
3038
3039 return file_has_perm(cred, file, av);
3040 }
3041
3042 error:
3043 return rc;
3044 }
3045
3046 static int selinux_file_mmap(struct file *file, unsigned long reqprot,
3047 unsigned long prot, unsigned long flags,
3048 unsigned long addr, unsigned long addr_only)
3049 {
3050 int rc = 0;
3051 u32 sid = current_sid();
3052
3053 /*
3054 * notice that we are intentionally putting the SELinux check before
3055 * the secondary cap_file_mmap check. This is such a likely attempt
3056 * at bad behaviour/exploit that we always want to get the AVC, even
3057 * if DAC would have also denied the operation.
3058 */
3059 if (addr < CONFIG_LSM_MMAP_MIN_ADDR) {
3060 rc = avc_has_perm(sid, sid, SECCLASS_MEMPROTECT,
3061 MEMPROTECT__MMAP_ZERO, NULL);
3062 if (rc)
3063 return rc;
3064 }
3065
3066 /* do DAC check on address space usage */
3067 rc = cap_file_mmap(file, reqprot, prot, flags, addr, addr_only);
3068 if (rc || addr_only)
3069 return rc;
3070
3071 if (selinux_checkreqprot)
3072 prot = reqprot;
3073
3074 return file_map_prot_check(file, prot,
3075 (flags & MAP_TYPE) == MAP_SHARED);
3076 }
3077
3078 static int selinux_file_mprotect(struct vm_area_struct *vma,
3079 unsigned long reqprot,
3080 unsigned long prot)
3081 {
3082 const struct cred *cred = current_cred();
3083
3084 if (selinux_checkreqprot)
3085 prot = reqprot;
3086
3087 if (default_noexec &&
3088 (prot & PROT_EXEC) && !(vma->vm_flags & VM_EXEC)) {
3089 int rc = 0;
3090 if (vma->vm_start >= vma->vm_mm->start_brk &&
3091 vma->vm_end <= vma->vm_mm->brk) {
3092 rc = cred_has_perm(cred, cred, PROCESS__EXECHEAP);
3093 } else if (!vma->vm_file &&
3094 vma->vm_start <= vma->vm_mm->start_stack &&
3095 vma->vm_end >= vma->vm_mm->start_stack) {
3096 rc = current_has_perm(current, PROCESS__EXECSTACK);
3097 } else if (vma->vm_file && vma->anon_vma) {
3098 /*
3099 * We are making executable a file mapping that has
3100 * had some COW done. Since pages might have been
3101 * written, check ability to execute the possibly
3102 * modified content. This typically should only
3103 * occur for text relocations.
3104 */
3105 rc = file_has_perm(cred, vma->vm_file, FILE__EXECMOD);
3106 }
3107 if (rc)
3108 return rc;
3109 }
3110
3111 return file_map_prot_check(vma->vm_file, prot, vma->vm_flags&VM_SHARED);
3112 }
3113
3114 static int selinux_file_lock(struct file *file, unsigned int cmd)
3115 {
3116 const struct cred *cred = current_cred();
3117
3118 return file_has_perm(cred, file, FILE__LOCK);
3119 }
3120
3121 static int selinux_file_fcntl(struct file *file, unsigned int cmd,
3122 unsigned long arg)
3123 {
3124 const struct cred *cred = current_cred();
3125 int err = 0;
3126
3127 switch (cmd) {
3128 case F_SETFL:
3129 if (!file->f_path.dentry || !file->f_path.dentry->d_inode) {
3130 err = -EINVAL;
3131 break;
3132 }
3133
3134 if ((file->f_flags & O_APPEND) && !(arg & O_APPEND)) {
3135 err = file_has_perm(cred, file, FILE__WRITE);
3136 break;
3137 }
3138 /* fall through */
3139 case F_SETOWN:
3140 case F_SETSIG:
3141 case F_GETFL:
3142 case F_GETOWN:
3143 case F_GETSIG:
3144 /* Just check FD__USE permission */
3145 err = file_has_perm(cred, file, 0);
3146 break;
3147 case F_GETLK:
3148 case F_SETLK:
3149 case F_SETLKW:
3150 #if BITS_PER_LONG == 32
3151 case F_GETLK64:
3152 case F_SETLK64:
3153 case F_SETLKW64:
3154 #endif
3155 if (!file->f_path.dentry || !file->f_path.dentry->d_inode) {
3156 err = -EINVAL;
3157 break;
3158 }
3159 err = file_has_perm(cred, file, FILE__LOCK);
3160 break;
3161 }
3162
3163 return err;
3164 }
3165
3166 static int selinux_file_set_fowner(struct file *file)
3167 {
3168 struct file_security_struct *fsec;
3169
3170 fsec = file->f_security;
3171 fsec->fown_sid = current_sid();
3172
3173 return 0;
3174 }
3175
3176 static int selinux_file_send_sigiotask(struct task_struct *tsk,
3177 struct fown_struct *fown, int signum)
3178 {
3179 struct file *file;
3180 u32 sid = task_sid(tsk);
3181 u32 perm;
3182 struct file_security_struct *fsec;
3183
3184 /* struct fown_struct is never outside the context of a struct file */
3185 file = container_of(fown, struct file, f_owner);
3186
3187 fsec = file->f_security;
3188
3189 if (!signum)
3190 perm = signal_to_av(SIGIO); /* as per send_sigio_to_task */
3191 else
3192 perm = signal_to_av(signum);
3193
3194 return avc_has_perm(fsec->fown_sid, sid,
3195 SECCLASS_PROCESS, perm, NULL);
3196 }
3197
3198 static int selinux_file_receive(struct file *file)
3199 {
3200 const struct cred *cred = current_cred();
3201
3202 return file_has_perm(cred, file, file_to_av(file));
3203 }
3204
3205 static int selinux_dentry_open(struct file *file, const struct cred *cred)
3206 {
3207 struct file_security_struct *fsec;
3208 struct inode *inode;
3209 struct inode_security_struct *isec;
3210
3211 inode = file->f_path.dentry->d_inode;
3212 fsec = file->f_security;
3213 isec = inode->i_security;
3214 /*
3215 * Save inode label and policy sequence number
3216 * at open-time so that selinux_file_permission
3217 * can determine whether revalidation is necessary.
3218 * Task label is already saved in the file security
3219 * struct as its SID.
3220 */
3221 fsec->isid = isec->sid;
3222 fsec->pseqno = avc_policy_seqno();
3223 /*
3224 * Since the inode label or policy seqno may have changed
3225 * between the selinux_inode_permission check and the saving
3226 * of state above, recheck that access is still permitted.
3227 * Otherwise, access might never be revalidated against the
3228 * new inode label or new policy.
3229 * This check is not redundant - do not remove.
3230 */
3231 return inode_has_perm_noadp(cred, inode, open_file_to_av(file), 0);
3232 }
3233
3234 /* task security operations */
3235
3236 static int selinux_task_create(unsigned long clone_flags)
3237 {
3238 return current_has_perm(current, PROCESS__FORK);
3239 }
3240
3241 /*
3242 * allocate the SELinux part of blank credentials
3243 */
3244 static int selinux_cred_alloc_blank(struct cred *cred, gfp_t gfp)
3245 {
3246 struct task_security_struct *tsec;
3247
3248 tsec = kzalloc(sizeof(struct task_security_struct), gfp);
3249 if (!tsec)
3250 return -ENOMEM;
3251
3252 cred->security = tsec;
3253 return 0;
3254 }
3255
3256 /*
3257 * detach and free the LSM part of a set of credentials
3258 */
3259 static void selinux_cred_free(struct cred *cred)
3260 {
3261 struct task_security_struct *tsec = cred->security;
3262
3263 /*
3264 * cred->security == NULL if security_cred_alloc_blank() or
3265 * security_prepare_creds() returned an error.
3266 */
3267 BUG_ON(cred->security && (unsigned long) cred->security < PAGE_SIZE);
3268 cred->security = (void *) 0x7UL;
3269 kfree(tsec);
3270 }
3271
3272 /*
3273 * prepare a new set of credentials for modification
3274 */
3275 static int selinux_cred_prepare(struct cred *new, const struct cred *old,
3276 gfp_t gfp)
3277 {
3278 const struct task_security_struct *old_tsec;
3279 struct task_security_struct *tsec;
3280
3281 old_tsec = old->security;
3282
3283 tsec = kmemdup(old_tsec, sizeof(struct task_security_struct), gfp);
3284 if (!tsec)
3285 return -ENOMEM;
3286
3287 new->security = tsec;
3288 return 0;
3289 }
3290
3291 /*
3292 * transfer the SELinux data to a blank set of creds
3293 */
3294 static void selinux_cred_transfer(struct cred *new, const struct cred *old)
3295 {
3296 const struct task_security_struct *old_tsec = old->security;
3297 struct task_security_struct *tsec = new->security;
3298
3299 *tsec = *old_tsec;
3300 }
3301
3302 /*
3303 * set the security data for a kernel service
3304 * - all the creation contexts are set to unlabelled
3305 */
3306 static int selinux_kernel_act_as(struct cred *new, u32 secid)
3307 {
3308 struct task_security_struct *tsec = new->security;
3309 u32 sid = current_sid();
3310 int ret;
3311
3312 ret = avc_has_perm(sid, secid,
3313 SECCLASS_KERNEL_SERVICE,
3314 KERNEL_SERVICE__USE_AS_OVERRIDE,
3315 NULL);
3316 if (ret == 0) {
3317 tsec->sid = secid;
3318 tsec->create_sid = 0;
3319 tsec->keycreate_sid = 0;
3320 tsec->sockcreate_sid = 0;
3321 }
3322 return ret;
3323 }
3324
3325 /*
3326 * set the file creation context in a security record to the same as the
3327 * objective context of the specified inode
3328 */
3329 static int selinux_kernel_create_files_as(struct cred *new, struct inode *inode)
3330 {
3331 struct inode_security_struct *isec = inode->i_security;
3332 struct task_security_struct *tsec = new->security;
3333 u32 sid = current_sid();
3334 int ret;
3335
3336 ret = avc_has_perm(sid, isec->sid,
3337 SECCLASS_KERNEL_SERVICE,
3338 KERNEL_SERVICE__CREATE_FILES_AS,
3339 NULL);
3340
3341 if (ret == 0)
3342 tsec->create_sid = isec->sid;
3343 return ret;
3344 }
3345
3346 static int selinux_kernel_module_request(char *kmod_name)
3347 {
3348 u32 sid;
3349 struct common_audit_data ad;
3350
3351 sid = task_sid(current);
3352
3353 COMMON_AUDIT_DATA_INIT(&ad, KMOD);
3354 ad.u.kmod_name = kmod_name;
3355
3356 return avc_has_perm(sid, SECINITSID_KERNEL, SECCLASS_SYSTEM,
3357 SYSTEM__MODULE_REQUEST, &ad);
3358 }
3359
3360 static int selinux_task_setpgid(struct task_struct *p, pid_t pgid)
3361 {
3362 return current_has_perm(p, PROCESS__SETPGID);
3363 }
3364
3365 static int selinux_task_getpgid(struct task_struct *p)
3366 {
3367 return current_has_perm(p, PROCESS__GETPGID);
3368 }
3369
3370 static int selinux_task_getsid(struct task_struct *p)
3371 {
3372 return current_has_perm(p, PROCESS__GETSESSION);
3373 }
3374
3375 static void selinux_task_getsecid(struct task_struct *p, u32 *secid)
3376 {
3377 *secid = task_sid(p);
3378 }
3379
3380 static int selinux_task_setnice(struct task_struct *p, int nice)
3381 {
3382 int rc;
3383
3384 rc = cap_task_setnice(p, nice);
3385 if (rc)
3386 return rc;
3387
3388 return current_has_perm(p, PROCESS__SETSCHED);
3389 }
3390
3391 static int selinux_task_setioprio(struct task_struct *p, int ioprio)
3392 {
3393 int rc;
3394
3395 rc = cap_task_setioprio(p, ioprio);
3396 if (rc)
3397 return rc;
3398
3399 return current_has_perm(p, PROCESS__SETSCHED);
3400 }
3401
3402 static int selinux_task_getioprio(struct task_struct *p)
3403 {
3404 return current_has_perm(p, PROCESS__GETSCHED);
3405 }
3406
3407 static int selinux_task_setrlimit(struct task_struct *p, unsigned int resource,
3408 struct rlimit *new_rlim)
3409 {
3410 struct rlimit *old_rlim = p->signal->rlim + resource;
3411
3412 /* Control the ability to change the hard limit (whether
3413 lowering or raising it), so that the hard limit can
3414 later be used as a safe reset point for the soft limit
3415 upon context transitions. See selinux_bprm_committing_creds. */
3416 if (old_rlim->rlim_max != new_rlim->rlim_max)
3417 return current_has_perm(p, PROCESS__SETRLIMIT);
3418
3419 return 0;
3420 }
3421
3422 static int selinux_task_setscheduler(struct task_struct *p)
3423 {
3424 int rc;
3425
3426 rc = cap_task_setscheduler(p);
3427 if (rc)
3428 return rc;
3429
3430 return current_has_perm(p, PROCESS__SETSCHED);
3431 }
3432
3433 static int selinux_task_getscheduler(struct task_struct *p)
3434 {
3435 return current_has_perm(p, PROCESS__GETSCHED);
3436 }
3437
3438 static int selinux_task_movememory(struct task_struct *p)
3439 {
3440 return current_has_perm(p, PROCESS__SETSCHED);
3441 }
3442
3443 static int selinux_task_kill(struct task_struct *p, struct siginfo *info,
3444 int sig, u32 secid)
3445 {
3446 u32 perm;
3447 int rc;
3448
3449 if (!sig)
3450 perm = PROCESS__SIGNULL; /* null signal; existence test */
3451 else
3452 perm = signal_to_av(sig);
3453 if (secid)
3454 rc = avc_has_perm(secid, task_sid(p),
3455 SECCLASS_PROCESS, perm, NULL);
3456 else
3457 rc = current_has_perm(p, perm);
3458 return rc;
3459 }
3460
3461 static int selinux_task_wait(struct task_struct *p)
3462 {
3463 return task_has_perm(p, current, PROCESS__SIGCHLD);
3464 }
3465
3466 static void selinux_task_to_inode(struct task_struct *p,
3467 struct inode *inode)
3468 {
3469 struct inode_security_struct *isec = inode->i_security;
3470 u32 sid = task_sid(p);
3471
3472 isec->sid = sid;
3473 isec->initialized = 1;
3474 }
3475
3476 /* Returns error only if unable to parse addresses */
3477 static int selinux_parse_skb_ipv4(struct sk_buff *skb,
3478 struct common_audit_data *ad, u8 *proto)
3479 {
3480 int offset, ihlen, ret = -EINVAL;
3481 struct iphdr _iph, *ih;
3482
3483 offset = skb_network_offset(skb);
3484 ih = skb_header_pointer(skb, offset, sizeof(_iph), &_iph);
3485 if (ih == NULL)
3486 goto out;
3487
3488 ihlen = ih->ihl * 4;
3489 if (ihlen < sizeof(_iph))
3490 goto out;
3491
3492 ad->u.net.v4info.saddr = ih->saddr;
3493 ad->u.net.v4info.daddr = ih->daddr;
3494 ret = 0;
3495
3496 if (proto)
3497 *proto = ih->protocol;
3498
3499 switch (ih->protocol) {
3500 case IPPROTO_TCP: {
3501 struct tcphdr _tcph, *th;
3502
3503 if (ntohs(ih->frag_off) & IP_OFFSET)
3504 break;
3505
3506 offset += ihlen;
3507 th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph);
3508 if (th == NULL)
3509 break;
3510
3511 ad->u.net.sport = th->source;
3512 ad->u.net.dport = th->dest;
3513 break;
3514 }
3515
3516 case IPPROTO_UDP: {
3517 struct udphdr _udph, *uh;
3518
3519 if (ntohs(ih->frag_off) & IP_OFFSET)
3520 break;
3521
3522 offset += ihlen;
3523 uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph);
3524 if (uh == NULL)
3525 break;
3526
3527 ad->u.net.sport = uh->source;
3528 ad->u.net.dport = uh->dest;
3529 break;
3530 }
3531
3532 case IPPROTO_DCCP: {
3533 struct dccp_hdr _dccph, *dh;
3534
3535 if (ntohs(ih->frag_off) & IP_OFFSET)
3536 break;
3537
3538 offset += ihlen;
3539 dh = skb_header_pointer(skb, offset, sizeof(_dccph), &_dccph);
3540 if (dh == NULL)
3541 break;
3542
3543 ad->u.net.sport = dh->dccph_sport;
3544 ad->u.net.dport = dh->dccph_dport;
3545 break;
3546 }
3547
3548 default:
3549 break;
3550 }
3551 out:
3552 return ret;
3553 }
3554
3555 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
3556
3557 /* Returns error only if unable to parse addresses */
3558 static int selinux_parse_skb_ipv6(struct sk_buff *skb,
3559 struct common_audit_data *ad, u8 *proto)
3560 {
3561 u8 nexthdr;
3562 int ret = -EINVAL, offset;
3563 struct ipv6hdr _ipv6h, *ip6;
3564
3565 offset = skb_network_offset(skb);
3566 ip6 = skb_header_pointer(skb, offset, sizeof(_ipv6h), &_ipv6h);
3567 if (ip6 == NULL)
3568 goto out;
3569
3570 ipv6_addr_copy(&ad->u.net.v6info.saddr, &ip6->saddr);
3571 ipv6_addr_copy(&ad->u.net.v6info.daddr, &ip6->daddr);
3572 ret = 0;
3573
3574 nexthdr = ip6->nexthdr;
3575 offset += sizeof(_ipv6h);
3576 offset = ipv6_skip_exthdr(skb, offset, &nexthdr);
3577 if (offset < 0)
3578 goto out;
3579
3580 if (proto)
3581 *proto = nexthdr;
3582
3583 switch (nexthdr) {
3584 case IPPROTO_TCP: {
3585 struct tcphdr _tcph, *th;
3586
3587 th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph);
3588 if (th == NULL)
3589 break;
3590
3591 ad->u.net.sport = th->source;
3592 ad->u.net.dport = th->dest;
3593 break;
3594 }
3595
3596 case IPPROTO_UDP: {
3597 struct udphdr _udph, *uh;
3598
3599 uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph);
3600 if (uh == NULL)
3601 break;
3602
3603 ad->u.net.sport = uh->source;
3604 ad->u.net.dport = uh->dest;
3605 break;
3606 }
3607
3608 case IPPROTO_DCCP: {
3609 struct dccp_hdr _dccph, *dh;
3610
3611 dh = skb_header_pointer(skb, offset, sizeof(_dccph), &_dccph);
3612 if (dh == NULL)
3613 break;
3614
3615 ad->u.net.sport = dh->dccph_sport;
3616 ad->u.net.dport = dh->dccph_dport;
3617 break;
3618 }
3619
3620 /* includes fragments */
3621 default:
3622 break;
3623 }
3624 out:
3625 return ret;
3626 }
3627
3628 #endif /* IPV6 */
3629
3630 static int selinux_parse_skb(struct sk_buff *skb, struct common_audit_data *ad,
3631 char **_addrp, int src, u8 *proto)
3632 {
3633 char *addrp;
3634 int ret;
3635
3636 switch (ad->u.net.family) {
3637 case PF_INET:
3638 ret = selinux_parse_skb_ipv4(skb, ad, proto);
3639 if (ret)
3640 goto parse_error;
3641 addrp = (char *)(src ? &ad->u.net.v4info.saddr :
3642 &ad->u.net.v4info.daddr);
3643 goto okay;
3644
3645 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
3646 case PF_INET6:
3647 ret = selinux_parse_skb_ipv6(skb, ad, proto);
3648 if (ret)
3649 goto parse_error;
3650 addrp = (char *)(src ? &ad->u.net.v6info.saddr :
3651 &ad->u.net.v6info.daddr);
3652 goto okay;
3653 #endif /* IPV6 */
3654 default:
3655 addrp = NULL;
3656 goto okay;
3657 }
3658
3659 parse_error:
3660 printk(KERN_WARNING
3661 "SELinux: failure in selinux_parse_skb(),"
3662 " unable to parse packet\n");
3663 return ret;
3664
3665 okay:
3666 if (_addrp)
3667 *_addrp = addrp;
3668 return 0;
3669 }
3670
3671 /**
3672 * selinux_skb_peerlbl_sid - Determine the peer label of a packet
3673 * @skb: the packet
3674 * @family: protocol family
3675 * @sid: the packet's peer label SID
3676 *
3677 * Description:
3678 * Check the various different forms of network peer labeling and determine
3679 * the peer label/SID for the packet; most of the magic actually occurs in
3680 * the security server function security_net_peersid_cmp(). The function
3681 * returns zero if the value in @sid is valid (although it may be SECSID_NULL)
3682 * or -EACCES if @sid is invalid due to inconsistencies with the different
3683 * peer labels.
3684 *
3685 */
3686 static int selinux_skb_peerlbl_sid(struct sk_buff *skb, u16 family, u32 *sid)
3687 {
3688 int err;
3689 u32 xfrm_sid;
3690 u32 nlbl_sid;
3691 u32 nlbl_type;
3692
3693 selinux_skb_xfrm_sid(skb, &xfrm_sid);
3694 selinux_netlbl_skbuff_getsid(skb, family, &nlbl_type, &nlbl_sid);
3695
3696 err = security_net_peersid_resolve(nlbl_sid, nlbl_type, xfrm_sid, sid);
3697 if (unlikely(err)) {
3698 printk(KERN_WARNING
3699 "SELinux: failure in selinux_skb_peerlbl_sid(),"
3700 " unable to determine packet's peer label\n");
3701 return -EACCES;
3702 }
3703
3704 return 0;
3705 }
3706
3707 /* socket security operations */
3708
3709 static int socket_sockcreate_sid(const struct task_security_struct *tsec,
3710 u16 secclass, u32 *socksid)
3711 {
3712 if (tsec->sockcreate_sid > SECSID_NULL) {
3713 *socksid = tsec->sockcreate_sid;
3714 return 0;
3715 }
3716
3717 return security_transition_sid(tsec->sid, tsec->sid, secclass, NULL,
3718 socksid);
3719 }
3720
3721 static int sock_has_perm(struct task_struct *task, struct sock *sk, u32 perms)
3722 {
3723 struct sk_security_struct *sksec = sk->sk_security;
3724 struct common_audit_data ad;
3725 u32 tsid = task_sid(task);
3726
3727 if (sksec->sid == SECINITSID_KERNEL)
3728 return 0;
3729
3730 COMMON_AUDIT_DATA_INIT(&ad, NET);
3731 ad.u.net.sk = sk;
3732
3733 return avc_has_perm(tsid, sksec->sid, sksec->sclass, perms, &ad);
3734 }
3735
3736 static int selinux_socket_create(int family, int type,
3737 int protocol, int kern)
3738 {
3739 const struct task_security_struct *tsec = current_security();
3740 u32 newsid;
3741 u16 secclass;
3742 int rc;
3743
3744 if (kern)
3745 return 0;
3746
3747 secclass = socket_type_to_security_class(family, type, protocol);
3748 rc = socket_sockcreate_sid(tsec, secclass, &newsid);
3749 if (rc)
3750 return rc;
3751
3752 return avc_has_perm(tsec->sid, newsid, secclass, SOCKET__CREATE, NULL);
3753 }
3754
3755 static int selinux_socket_post_create(struct socket *sock, int family,
3756 int type, int protocol, int kern)
3757 {
3758 const struct task_security_struct *tsec = current_security();
3759 struct inode_security_struct *isec = SOCK_INODE(sock)->i_security;
3760 struct sk_security_struct *sksec;
3761 int err = 0;
3762
3763 isec->sclass = socket_type_to_security_class(family, type, protocol);
3764
3765 if (kern)
3766 isec->sid = SECINITSID_KERNEL;
3767 else {
3768 err = socket_sockcreate_sid(tsec, isec->sclass, &(isec->sid));
3769 if (err)
3770 return err;
3771 }
3772
3773 isec->initialized = 1;
3774
3775 if (sock->sk) {
3776 sksec = sock->sk->sk_security;
3777 sksec->sid = isec->sid;
3778 sksec->sclass = isec->sclass;
3779 err = selinux_netlbl_socket_post_create(sock->sk, family);
3780 }
3781
3782 return err;
3783 }
3784
3785 /* Range of port numbers used to automatically bind.
3786 Need to determine whether we should perform a name_bind
3787 permission check between the socket and the port number. */
3788
3789 static int selinux_socket_bind(struct socket *sock, struct sockaddr *address, int addrlen)
3790 {
3791 struct sock *sk = sock->sk;
3792 u16 family;
3793 int err;
3794
3795 err = sock_has_perm(current, sk, SOCKET__BIND);
3796 if (err)
3797 goto out;
3798
3799 /*
3800 * If PF_INET or PF_INET6, check name_bind permission for the port.
3801 * Multiple address binding for SCTP is not supported yet: we just
3802 * check the first address now.
3803 */
3804 family = sk->sk_family;
3805 if (family == PF_INET || family == PF_INET6) {
3806 char *addrp;
3807 struct sk_security_struct *sksec = sk->sk_security;
3808 struct common_audit_data ad;
3809 struct sockaddr_in *addr4 = NULL;
3810 struct sockaddr_in6 *addr6 = NULL;
3811 unsigned short snum;
3812 u32 sid, node_perm;
3813
3814 if (family == PF_INET) {
3815 addr4 = (struct sockaddr_in *)address;
3816 snum = ntohs(addr4->sin_port);
3817 addrp = (char *)&addr4->sin_addr.s_addr;
3818 } else {
3819 addr6 = (struct sockaddr_in6 *)address;
3820 snum = ntohs(addr6->sin6_port);
3821 addrp = (char *)&addr6->sin6_addr.s6_addr;
3822 }
3823
3824 if (snum) {
3825 int low, high;
3826
3827 inet_get_local_port_range(&low, &high);
3828
3829 if (snum < max(PROT_SOCK, low) || snum > high) {
3830 err = sel_netport_sid(sk->sk_protocol,
3831 snum, &sid);
3832 if (err)
3833 goto out;
3834 COMMON_AUDIT_DATA_INIT(&ad, NET);
3835 ad.u.net.sport = htons(snum);
3836 ad.u.net.family = family;
3837 err = avc_has_perm(sksec->sid, sid,
3838 sksec->sclass,
3839 SOCKET__NAME_BIND, &ad);
3840 if (err)
3841 goto out;
3842 }
3843 }
3844
3845 switch (sksec->sclass) {
3846 case SECCLASS_TCP_SOCKET:
3847 node_perm = TCP_SOCKET__NODE_BIND;
3848 break;
3849
3850 case SECCLASS_UDP_SOCKET:
3851 node_perm = UDP_SOCKET__NODE_BIND;
3852 break;
3853
3854 case SECCLASS_DCCP_SOCKET:
3855 node_perm = DCCP_SOCKET__NODE_BIND;
3856 break;
3857
3858 default:
3859 node_perm = RAWIP_SOCKET__NODE_BIND;
3860 break;
3861 }
3862
3863 err = sel_netnode_sid(addrp, family, &sid);
3864 if (err)
3865 goto out;
3866
3867 COMMON_AUDIT_DATA_INIT(&ad, NET);
3868 ad.u.net.sport = htons(snum);
3869 ad.u.net.family = family;
3870
3871 if (family == PF_INET)
3872 ad.u.net.v4info.saddr = addr4->sin_addr.s_addr;
3873 else
3874 ipv6_addr_copy(&ad.u.net.v6info.saddr, &addr6->sin6_addr);
3875
3876 err = avc_has_perm(sksec->sid, sid,
3877 sksec->sclass, node_perm, &ad);
3878 if (err)
3879 goto out;
3880 }
3881 out:
3882 return err;
3883 }
3884
3885 static int selinux_socket_connect(struct socket *sock, struct sockaddr *address, int addrlen)
3886 {
3887 struct sock *sk = sock->sk;
3888 struct sk_security_struct *sksec = sk->sk_security;
3889 int err;
3890
3891 err = sock_has_perm(current, sk, SOCKET__CONNECT);
3892 if (err)
3893 return err;
3894
3895 /*
3896 * If a TCP or DCCP socket, check name_connect permission for the port.
3897 */
3898 if (sksec->sclass == SECCLASS_TCP_SOCKET ||
3899 sksec->sclass == SECCLASS_DCCP_SOCKET) {
3900 struct common_audit_data ad;
3901 struct sockaddr_in *addr4 = NULL;
3902 struct sockaddr_in6 *addr6 = NULL;
3903 unsigned short snum;
3904 u32 sid, perm;
3905
3906 if (sk->sk_family == PF_INET) {
3907 addr4 = (struct sockaddr_in *)address;
3908 if (addrlen < sizeof(struct sockaddr_in))
3909 return -EINVAL;
3910 snum = ntohs(addr4->sin_port);
3911 } else {
3912 addr6 = (struct sockaddr_in6 *)address;
3913 if (addrlen < SIN6_LEN_RFC2133)
3914 return -EINVAL;
3915 snum = ntohs(addr6->sin6_port);
3916 }
3917
3918 err = sel_netport_sid(sk->sk_protocol, snum, &sid);
3919 if (err)
3920 goto out;
3921
3922 perm = (sksec->sclass == SECCLASS_TCP_SOCKET) ?
3923 TCP_SOCKET__NAME_CONNECT : DCCP_SOCKET__NAME_CONNECT;
3924
3925 COMMON_AUDIT_DATA_INIT(&ad, NET);
3926 ad.u.net.dport = htons(snum);
3927 ad.u.net.family = sk->sk_family;
3928 err = avc_has_perm(sksec->sid, sid, sksec->sclass, perm, &ad);
3929 if (err)
3930 goto out;
3931 }
3932
3933 err = selinux_netlbl_socket_connect(sk, address);
3934
3935 out:
3936 return err;
3937 }
3938
3939 static int selinux_socket_listen(struct socket *sock, int backlog)
3940 {
3941 return sock_has_perm(current, sock->sk, SOCKET__LISTEN);
3942 }
3943
3944 static int selinux_socket_accept(struct socket *sock, struct socket *newsock)
3945 {
3946 int err;
3947 struct inode_security_struct *isec;
3948 struct inode_security_struct *newisec;
3949
3950 err = sock_has_perm(current, sock->sk, SOCKET__ACCEPT);
3951 if (err)
3952 return err;
3953
3954 newisec = SOCK_INODE(newsock)->i_security;
3955
3956 isec = SOCK_INODE(sock)->i_security;
3957 newisec->sclass = isec->sclass;
3958 newisec->sid = isec->sid;
3959 newisec->initialized = 1;
3960
3961 return 0;
3962 }
3963
3964 static int selinux_socket_sendmsg(struct socket *sock, struct msghdr *msg,
3965 int size)
3966 {
3967 return sock_has_perm(current, sock->sk, SOCKET__WRITE);
3968 }
3969
3970 static int selinux_socket_recvmsg(struct socket *sock, struct msghdr *msg,
3971 int size, int flags)
3972 {
3973 return sock_has_perm(current, sock->sk, SOCKET__READ);
3974 }
3975
3976 static int selinux_socket_getsockname(struct socket *sock)
3977 {
3978 return sock_has_perm(current, sock->sk, SOCKET__GETATTR);
3979 }
3980
3981 static int selinux_socket_getpeername(struct socket *sock)
3982 {
3983 return sock_has_perm(current, sock->sk, SOCKET__GETATTR);
3984 }
3985
3986 static int selinux_socket_setsockopt(struct socket *sock, int level, int optname)
3987 {
3988 int err;
3989
3990 err = sock_has_perm(current, sock->sk, SOCKET__SETOPT);
3991 if (err)
3992 return err;
3993
3994 return selinux_netlbl_socket_setsockopt(sock, level, optname);
3995 }
3996
3997 static int selinux_socket_getsockopt(struct socket *sock, int level,
3998 int optname)
3999 {
4000 return sock_has_perm(current, sock->sk, SOCKET__GETOPT);
4001 }
4002
4003 static int selinux_socket_shutdown(struct socket *sock, int how)
4004 {
4005 return sock_has_perm(current, sock->sk, SOCKET__SHUTDOWN);
4006 }
4007
4008 static int selinux_socket_unix_stream_connect(struct sock *sock,
4009 struct sock *other,
4010 struct sock *newsk)
4011 {
4012 struct sk_security_struct *sksec_sock = sock->sk_security;
4013 struct sk_security_struct *sksec_other = other->sk_security;
4014 struct sk_security_struct *sksec_new = newsk->sk_security;
4015 struct common_audit_data ad;
4016 int err;
4017
4018 COMMON_AUDIT_DATA_INIT(&ad, NET);
4019 ad.u.net.sk = other;
4020
4021 err = avc_has_perm(sksec_sock->sid, sksec_other->sid,
4022 sksec_other->sclass,
4023 UNIX_STREAM_SOCKET__CONNECTTO, &ad);
4024 if (err)
4025 return err;
4026
4027 /* server child socket */
4028 sksec_new->peer_sid = sksec_sock->sid;
4029 err = security_sid_mls_copy(sksec_other->sid, sksec_sock->sid,
4030 &sksec_new->sid);
4031 if (err)
4032 return err;
4033
4034 /* connecting socket */
4035 sksec_sock->peer_sid = sksec_new->sid;
4036
4037 return 0;
4038 }
4039
4040 static int selinux_socket_unix_may_send(struct socket *sock,
4041 struct socket *other)
4042 {
4043 struct sk_security_struct *ssec = sock->sk->sk_security;
4044 struct sk_security_struct *osec = other->sk->sk_security;
4045 struct common_audit_data ad;
4046
4047 COMMON_AUDIT_DATA_INIT(&ad, NET);
4048 ad.u.net.sk = other->sk;
4049
4050 return avc_has_perm(ssec->sid, osec->sid, osec->sclass, SOCKET__SENDTO,
4051 &ad);
4052 }
4053
4054 static int selinux_inet_sys_rcv_skb(int ifindex, char *addrp, u16 family,
4055 u32 peer_sid,
4056 struct common_audit_data *ad)
4057 {
4058 int err;
4059 u32 if_sid;
4060 u32 node_sid;
4061
4062 err = sel_netif_sid(ifindex, &if_sid);
4063 if (err)
4064 return err;
4065 err = avc_has_perm(peer_sid, if_sid,
4066 SECCLASS_NETIF, NETIF__INGRESS, ad);
4067 if (err)
4068 return err;
4069
4070 err = sel_netnode_sid(addrp, family, &node_sid);
4071 if (err)
4072 return err;
4073 return avc_has_perm(peer_sid, node_sid,
4074 SECCLASS_NODE, NODE__RECVFROM, ad);
4075 }
4076
4077 static int selinux_sock_rcv_skb_compat(struct sock *sk, struct sk_buff *skb,
4078 u16 family)
4079 {
4080 int err = 0;
4081 struct sk_security_struct *sksec = sk->sk_security;
4082 u32 sk_sid = sksec->sid;
4083 struct common_audit_data ad;
4084 char *addrp;
4085
4086 COMMON_AUDIT_DATA_INIT(&ad, NET);
4087 ad.u.net.netif = skb->skb_iif;
4088 ad.u.net.family = family;
4089 err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL);
4090 if (err)
4091 return err;
4092
4093 if (selinux_secmark_enabled()) {
4094 err = avc_has_perm(sk_sid, skb->secmark, SECCLASS_PACKET,
4095 PACKET__RECV, &ad);
4096 if (err)
4097 return err;
4098 }
4099
4100 err = selinux_netlbl_sock_rcv_skb(sksec, skb, family, &ad);
4101 if (err)
4102 return err;
4103 err = selinux_xfrm_sock_rcv_skb(sksec->sid, skb, &ad);
4104
4105 return err;
4106 }
4107
4108 static int selinux_socket_sock_rcv_skb(struct sock *sk, struct sk_buff *skb)
4109 {
4110 int err;
4111 struct sk_security_struct *sksec = sk->sk_security;
4112 u16 family = sk->sk_family;
4113 u32 sk_sid = sksec->sid;
4114 struct common_audit_data ad;
4115 char *addrp;
4116 u8 secmark_active;
4117 u8 peerlbl_active;
4118
4119 if (family != PF_INET && family != PF_INET6)
4120 return 0;
4121
4122 /* Handle mapped IPv4 packets arriving via IPv6 sockets */
4123 if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
4124 family = PF_INET;
4125
4126 /* If any sort of compatibility mode is enabled then handoff processing
4127 * to the selinux_sock_rcv_skb_compat() function to deal with the
4128 * special handling. We do this in an attempt to keep this function
4129 * as fast and as clean as possible. */
4130 if (!selinux_policycap_netpeer)
4131 return selinux_sock_rcv_skb_compat(sk, skb, family);
4132
4133 secmark_active = selinux_secmark_enabled();
4134 peerlbl_active = netlbl_enabled() || selinux_xfrm_enabled();
4135 if (!secmark_active && !peerlbl_active)
4136 return 0;
4137
4138 COMMON_AUDIT_DATA_INIT(&ad, NET);
4139 ad.u.net.netif = skb->skb_iif;
4140 ad.u.net.family = family;
4141 err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL);
4142 if (err)
4143 return err;
4144
4145 if (peerlbl_active) {
4146 u32 peer_sid;
4147
4148 err = selinux_skb_peerlbl_sid(skb, family, &peer_sid);
4149 if (err)
4150 return err;
4151 err = selinux_inet_sys_rcv_skb(skb->skb_iif, addrp, family,
4152 peer_sid, &ad);
4153 if (err) {
4154 selinux_netlbl_err(skb, err, 0);
4155 return err;
4156 }
4157 err = avc_has_perm(sk_sid, peer_sid, SECCLASS_PEER,
4158 PEER__RECV, &ad);
4159 if (err)
4160 selinux_netlbl_err(skb, err, 0);
4161 }
4162
4163 if (secmark_active) {
4164 err = avc_has_perm(sk_sid, skb->secmark, SECCLASS_PACKET,
4165 PACKET__RECV, &ad);
4166 if (err)
4167 return err;
4168 }
4169
4170 return err;
4171 }
4172
4173 static int selinux_socket_getpeersec_stream(struct socket *sock, char __user *optval,
4174 int __user *optlen, unsigned len)
4175 {
4176 int err = 0;
4177 char *scontext;
4178 u32 scontext_len;
4179 struct sk_security_struct *sksec = sock->sk->sk_security;
4180 u32 peer_sid = SECSID_NULL;
4181
4182 if (sksec->sclass == SECCLASS_UNIX_STREAM_SOCKET ||
4183 sksec->sclass == SECCLASS_TCP_SOCKET)
4184 peer_sid = sksec->peer_sid;
4185 if (peer_sid == SECSID_NULL)
4186 return -ENOPROTOOPT;
4187
4188 err = security_sid_to_context(peer_sid, &scontext, &scontext_len);
4189 if (err)
4190 return err;
4191
4192 if (scontext_len > len) {
4193 err = -ERANGE;
4194 goto out_len;
4195 }
4196
4197 if (copy_to_user(optval, scontext, scontext_len))
4198 err = -EFAULT;
4199
4200 out_len:
4201 if (put_user(scontext_len, optlen))
4202 err = -EFAULT;
4203 kfree(scontext);
4204 return err;
4205 }
4206
4207 static int selinux_socket_getpeersec_dgram(struct socket *sock, struct sk_buff *skb, u32 *secid)
4208 {
4209 u32 peer_secid = SECSID_NULL;
4210 u16 family;
4211
4212 if (skb && skb->protocol == htons(ETH_P_IP))
4213 family = PF_INET;
4214 else if (skb && skb->protocol == htons(ETH_P_IPV6))
4215 family = PF_INET6;
4216 else if (sock)
4217 family = sock->sk->sk_family;
4218 else
4219 goto out;
4220
4221 if (sock && family == PF_UNIX)
4222 selinux_inode_getsecid(SOCK_INODE(sock), &peer_secid);
4223 else if (skb)
4224 selinux_skb_peerlbl_sid(skb, family, &peer_secid);
4225
4226 out:
4227 *secid = peer_secid;
4228 if (peer_secid == SECSID_NULL)
4229 return -EINVAL;
4230 return 0;
4231 }
4232
4233 static int selinux_sk_alloc_security(struct sock *sk, int family, gfp_t priority)
4234 {
4235 struct sk_security_struct *sksec;
4236
4237 sksec = kzalloc(sizeof(*sksec), priority);
4238 if (!sksec)
4239 return -ENOMEM;
4240
4241 sksec->peer_sid = SECINITSID_UNLABELED;
4242 sksec->sid = SECINITSID_UNLABELED;
4243 selinux_netlbl_sk_security_reset(sksec);
4244 sk->sk_security = sksec;
4245
4246 return 0;
4247 }
4248
4249 static void selinux_sk_free_security(struct sock *sk)
4250 {
4251 struct sk_security_struct *sksec = sk->sk_security;
4252
4253 sk->sk_security = NULL;
4254 selinux_netlbl_sk_security_free(sksec);
4255 kfree(sksec);
4256 }
4257
4258 static void selinux_sk_clone_security(const struct sock *sk, struct sock *newsk)
4259 {
4260 struct sk_security_struct *sksec = sk->sk_security;
4261 struct sk_security_struct *newsksec = newsk->sk_security;
4262
4263 newsksec->sid = sksec->sid;
4264 newsksec->peer_sid = sksec->peer_sid;
4265 newsksec->sclass = sksec->sclass;
4266
4267 selinux_netlbl_sk_security_reset(newsksec);
4268 }
4269
4270 static void selinux_sk_getsecid(struct sock *sk, u32 *secid)
4271 {
4272 if (!sk)
4273 *secid = SECINITSID_ANY_SOCKET;
4274 else {
4275 struct sk_security_struct *sksec = sk->sk_security;
4276
4277 *secid = sksec->sid;
4278 }
4279 }
4280
4281 static void selinux_sock_graft(struct sock *sk, struct socket *parent)
4282 {
4283 struct inode_security_struct *isec = SOCK_INODE(parent)->i_security;
4284 struct sk_security_struct *sksec = sk->sk_security;
4285
4286 if (sk->sk_family == PF_INET || sk->sk_family == PF_INET6 ||
4287 sk->sk_family == PF_UNIX)
4288 isec->sid = sksec->sid;
4289 sksec->sclass = isec->sclass;
4290 }
4291
4292 static int selinux_inet_conn_request(struct sock *sk, struct sk_buff *skb,
4293 struct request_sock *req)
4294 {
4295 struct sk_security_struct *sksec = sk->sk_security;
4296 int err;
4297 u16 family = sk->sk_family;
4298 u32 newsid;
4299 u32 peersid;
4300
4301 /* handle mapped IPv4 packets arriving via IPv6 sockets */
4302 if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
4303 family = PF_INET;
4304
4305 err = selinux_skb_peerlbl_sid(skb, family, &peersid);
4306 if (err)
4307 return err;
4308 if (peersid == SECSID_NULL) {
4309 req->secid = sksec->sid;
4310 req->peer_secid = SECSID_NULL;
4311 } else {
4312 err = security_sid_mls_copy(sksec->sid, peersid, &newsid);
4313 if (err)
4314 return err;
4315 req->secid = newsid;
4316 req->peer_secid = peersid;
4317 }
4318
4319 return selinux_netlbl_inet_conn_request(req, family);
4320 }
4321
4322 static void selinux_inet_csk_clone(struct sock *newsk,
4323 const struct request_sock *req)
4324 {
4325 struct sk_security_struct *newsksec = newsk->sk_security;
4326
4327 newsksec->sid = req->secid;
4328 newsksec->peer_sid = req->peer_secid;
4329 /* NOTE: Ideally, we should also get the isec->sid for the
4330 new socket in sync, but we don't have the isec available yet.
4331 So we will wait until sock_graft to do it, by which
4332 time it will have been created and available. */
4333
4334 /* We don't need to take any sort of lock here as we are the only
4335 * thread with access to newsksec */
4336 selinux_netlbl_inet_csk_clone(newsk, req->rsk_ops->family);
4337 }
4338
4339 static void selinux_inet_conn_established(struct sock *sk, struct sk_buff *skb)
4340 {
4341 u16 family = sk->sk_family;
4342 struct sk_security_struct *sksec = sk->sk_security;
4343
4344 /* handle mapped IPv4 packets arriving via IPv6 sockets */
4345 if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
4346 family = PF_INET;
4347
4348 selinux_skb_peerlbl_sid(skb, family, &sksec->peer_sid);
4349 }
4350
4351 static int selinux_secmark_relabel_packet(u32 sid)
4352 {
4353 const struct task_security_struct *__tsec;
4354 u32 tsid;
4355
4356 __tsec = current_security();
4357 tsid = __tsec->sid;
4358
4359 return avc_has_perm(tsid, sid, SECCLASS_PACKET, PACKET__RELABELTO, NULL);
4360 }
4361
4362 static void selinux_secmark_refcount_inc(void)
4363 {
4364 atomic_inc(&selinux_secmark_refcount);
4365 }
4366
4367 static void selinux_secmark_refcount_dec(void)
4368 {
4369 atomic_dec(&selinux_secmark_refcount);
4370 }
4371
4372 static void selinux_req_classify_flow(const struct request_sock *req,
4373 struct flowi *fl)
4374 {
4375 fl->flowi_secid = req->secid;
4376 }
4377
4378 static int selinux_tun_dev_create(void)
4379 {
4380 u32 sid = current_sid();
4381
4382 /* we aren't taking into account the "sockcreate" SID since the socket
4383 * that is being created here is not a socket in the traditional sense,
4384 * instead it is a private sock, accessible only to the kernel, and
4385 * representing a wide range of network traffic spanning multiple
4386 * connections unlike traditional sockets - check the TUN driver to
4387 * get a better understanding of why this socket is special */
4388
4389 return avc_has_perm(sid, sid, SECCLASS_TUN_SOCKET, TUN_SOCKET__CREATE,
4390 NULL);
4391 }
4392
4393 static void selinux_tun_dev_post_create(struct sock *sk)
4394 {
4395 struct sk_security_struct *sksec = sk->sk_security;
4396
4397 /* we don't currently perform any NetLabel based labeling here and it
4398 * isn't clear that we would want to do so anyway; while we could apply
4399 * labeling without the support of the TUN user the resulting labeled
4400 * traffic from the other end of the connection would almost certainly
4401 * cause confusion to the TUN user that had no idea network labeling
4402 * protocols were being used */
4403
4404 /* see the comments in selinux_tun_dev_create() about why we don't use
4405 * the sockcreate SID here */
4406
4407 sksec->sid = current_sid();
4408 sksec->sclass = SECCLASS_TUN_SOCKET;
4409 }
4410
4411 static int selinux_tun_dev_attach(struct sock *sk)
4412 {
4413 struct sk_security_struct *sksec = sk->sk_security;
4414 u32 sid = current_sid();
4415 int err;
4416
4417 err = avc_has_perm(sid, sksec->sid, SECCLASS_TUN_SOCKET,
4418 TUN_SOCKET__RELABELFROM, NULL);
4419 if (err)
4420 return err;
4421 err = avc_has_perm(sid, sid, SECCLASS_TUN_SOCKET,
4422 TUN_SOCKET__RELABELTO, NULL);
4423 if (err)
4424 return err;
4425
4426 sksec->sid = sid;
4427
4428 return 0;
4429 }
4430
4431 static int selinux_nlmsg_perm(struct sock *sk, struct sk_buff *skb)
4432 {
4433 int err = 0;
4434 u32 perm;
4435 struct nlmsghdr *nlh;
4436 struct sk_security_struct *sksec = sk->sk_security;
4437
4438 if (skb->len < NLMSG_SPACE(0)) {
4439 err = -EINVAL;
4440 goto out;
4441 }
4442 nlh = nlmsg_hdr(skb);
4443
4444 err = selinux_nlmsg_lookup(sksec->sclass, nlh->nlmsg_type, &perm);
4445 if (err) {
4446 if (err == -EINVAL) {
4447 audit_log(current->audit_context, GFP_KERNEL, AUDIT_SELINUX_ERR,
4448 "SELinux: unrecognized netlink message"
4449 " type=%hu for sclass=%hu\n",
4450 nlh->nlmsg_type, sksec->sclass);
4451 if (!selinux_enforcing || security_get_allow_unknown())
4452 err = 0;
4453 }
4454
4455 /* Ignore */
4456 if (err == -ENOENT)
4457 err = 0;
4458 goto out;
4459 }
4460
4461 err = sock_has_perm(current, sk, perm);
4462 out:
4463 return err;
4464 }
4465
4466 #ifdef CONFIG_NETFILTER
4467
4468 static unsigned int selinux_ip_forward(struct sk_buff *skb, int ifindex,
4469 u16 family)
4470 {
4471 int err;
4472 char *addrp;
4473 u32 peer_sid;
4474 struct common_audit_data ad;
4475 u8 secmark_active;
4476 u8 netlbl_active;
4477 u8 peerlbl_active;
4478
4479 if (!selinux_policycap_netpeer)
4480 return NF_ACCEPT;
4481
4482 secmark_active = selinux_secmark_enabled();
4483 netlbl_active = netlbl_enabled();
4484 peerlbl_active = netlbl_active || selinux_xfrm_enabled();
4485 if (!secmark_active && !peerlbl_active)
4486 return NF_ACCEPT;
4487
4488 if (selinux_skb_peerlbl_sid(skb, family, &peer_sid) != 0)
4489 return NF_DROP;
4490
4491 COMMON_AUDIT_DATA_INIT(&ad, NET);
4492 ad.u.net.netif = ifindex;
4493 ad.u.net.family = family;
4494 if (selinux_parse_skb(skb, &ad, &addrp, 1, NULL) != 0)
4495 return NF_DROP;
4496
4497 if (peerlbl_active) {
4498 err = selinux_inet_sys_rcv_skb(ifindex, addrp, family,
4499 peer_sid, &ad);
4500 if (err) {
4501 selinux_netlbl_err(skb, err, 1);
4502 return NF_DROP;
4503 }
4504 }
4505
4506 if (secmark_active)
4507 if (avc_has_perm(peer_sid, skb->secmark,
4508 SECCLASS_PACKET, PACKET__FORWARD_IN, &ad))
4509 return NF_DROP;
4510
4511 if (netlbl_active)
4512 /* we do this in the FORWARD path and not the POST_ROUTING
4513 * path because we want to make sure we apply the necessary
4514 * labeling before IPsec is applied so we can leverage AH
4515 * protection */
4516 if (selinux_netlbl_skbuff_setsid(skb, family, peer_sid) != 0)
4517 return NF_DROP;
4518
4519 return NF_ACCEPT;
4520 }
4521
4522 static unsigned int selinux_ipv4_forward(unsigned int hooknum,
4523 struct sk_buff *skb,
4524 const struct net_device *in,
4525 const struct net_device *out,
4526 int (*okfn)(struct sk_buff *))
4527 {
4528 return selinux_ip_forward(skb, in->ifindex, PF_INET);
4529 }
4530
4531 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
4532 static unsigned int selinux_ipv6_forward(unsigned int hooknum,
4533 struct sk_buff *skb,
4534 const struct net_device *in,
4535 const struct net_device *out,
4536 int (*okfn)(struct sk_buff *))
4537 {
4538 return selinux_ip_forward(skb, in->ifindex, PF_INET6);
4539 }
4540 #endif /* IPV6 */
4541
4542 static unsigned int selinux_ip_output(struct sk_buff *skb,
4543 u16 family)
4544 {
4545 u32 sid;
4546
4547 if (!netlbl_enabled())
4548 return NF_ACCEPT;
4549
4550 /* we do this in the LOCAL_OUT path and not the POST_ROUTING path
4551 * because we want to make sure we apply the necessary labeling
4552 * before IPsec is applied so we can leverage AH protection */
4553 if (skb->sk) {
4554 struct sk_security_struct *sksec = skb->sk->sk_security;
4555 sid = sksec->sid;
4556 } else
4557 sid = SECINITSID_KERNEL;
4558 if (selinux_netlbl_skbuff_setsid(skb, family, sid) != 0)
4559 return NF_DROP;
4560
4561 return NF_ACCEPT;
4562 }
4563
4564 static unsigned int selinux_ipv4_output(unsigned int hooknum,
4565 struct sk_buff *skb,
4566 const struct net_device *in,
4567 const struct net_device *out,
4568 int (*okfn)(struct sk_buff *))
4569 {
4570 return selinux_ip_output(skb, PF_INET);
4571 }
4572
4573 static unsigned int selinux_ip_postroute_compat(struct sk_buff *skb,
4574 int ifindex,
4575 u16 family)
4576 {
4577 struct sock *sk = skb->sk;
4578 struct sk_security_struct *sksec;
4579 struct common_audit_data ad;
4580 char *addrp;
4581 u8 proto;
4582
4583 if (sk == NULL)
4584 return NF_ACCEPT;
4585 sksec = sk->sk_security;
4586
4587 COMMON_AUDIT_DATA_INIT(&ad, NET);
4588 ad.u.net.netif = ifindex;
4589 ad.u.net.family = family;
4590 if (selinux_parse_skb(skb, &ad, &addrp, 0, &proto))
4591 return NF_DROP;
4592
4593 if (selinux_secmark_enabled())
4594 if (avc_has_perm(sksec->sid, skb->secmark,
4595 SECCLASS_PACKET, PACKET__SEND, &ad))
4596 return NF_DROP_ERR(-ECONNREFUSED);
4597
4598 if (selinux_xfrm_postroute_last(sksec->sid, skb, &ad, proto))
4599 return NF_DROP_ERR(-ECONNREFUSED);
4600
4601 return NF_ACCEPT;
4602 }
4603
4604 static unsigned int selinux_ip_postroute(struct sk_buff *skb, int ifindex,
4605 u16 family)
4606 {
4607 u32 secmark_perm;
4608 u32 peer_sid;
4609 struct sock *sk;
4610 struct common_audit_data ad;
4611 char *addrp;
4612 u8 secmark_active;
4613 u8 peerlbl_active;
4614
4615 /* If any sort of compatibility mode is enabled then handoff processing
4616 * to the selinux_ip_postroute_compat() function to deal with the
4617 * special handling. We do this in an attempt to keep this function
4618 * as fast and as clean as possible. */
4619 if (!selinux_policycap_netpeer)
4620 return selinux_ip_postroute_compat(skb, ifindex, family);
4621 #ifdef CONFIG_XFRM
4622 /* If skb->dst->xfrm is non-NULL then the packet is undergoing an IPsec
4623 * packet transformation so allow the packet to pass without any checks
4624 * since we'll have another chance to perform access control checks
4625 * when the packet is on it's final way out.
4626 * NOTE: there appear to be some IPv6 multicast cases where skb->dst
4627 * is NULL, in this case go ahead and apply access control. */
4628 if (skb_dst(skb) != NULL && skb_dst(skb)->xfrm != NULL)
4629 return NF_ACCEPT;
4630 #endif
4631 secmark_active = selinux_secmark_enabled();
4632 peerlbl_active = netlbl_enabled() || selinux_xfrm_enabled();
4633 if (!secmark_active && !peerlbl_active)
4634 return NF_ACCEPT;
4635
4636 /* if the packet is being forwarded then get the peer label from the
4637 * packet itself; otherwise check to see if it is from a local
4638 * application or the kernel, if from an application get the peer label
4639 * from the sending socket, otherwise use the kernel's sid */
4640 sk = skb->sk;
4641 if (sk == NULL) {
4642 if (skb->skb_iif) {
4643 secmark_perm = PACKET__FORWARD_OUT;
4644 if (selinux_skb_peerlbl_sid(skb, family, &peer_sid))
4645 return NF_DROP;
4646 } else {
4647 secmark_perm = PACKET__SEND;
4648 peer_sid = SECINITSID_KERNEL;
4649 }
4650 } else {
4651 struct sk_security_struct *sksec = sk->sk_security;
4652 peer_sid = sksec->sid;
4653 secmark_perm = PACKET__SEND;
4654 }
4655
4656 COMMON_AUDIT_DATA_INIT(&ad, NET);
4657 ad.u.net.netif = ifindex;
4658 ad.u.net.family = family;
4659 if (selinux_parse_skb(skb, &ad, &addrp, 0, NULL))
4660 return NF_DROP;
4661
4662 if (secmark_active)
4663 if (avc_has_perm(peer_sid, skb->secmark,
4664 SECCLASS_PACKET, secmark_perm, &ad))
4665 return NF_DROP_ERR(-ECONNREFUSED);
4666
4667 if (peerlbl_active) {
4668 u32 if_sid;
4669 u32 node_sid;
4670
4671 if (sel_netif_sid(ifindex, &if_sid))
4672 return NF_DROP;
4673 if (avc_has_perm(peer_sid, if_sid,
4674 SECCLASS_NETIF, NETIF__EGRESS, &ad))
4675 return NF_DROP_ERR(-ECONNREFUSED);
4676
4677 if (sel_netnode_sid(addrp, family, &node_sid))
4678 return NF_DROP;
4679 if (avc_has_perm(peer_sid, node_sid,
4680 SECCLASS_NODE, NODE__SENDTO, &ad))
4681 return NF_DROP_ERR(-ECONNREFUSED);
4682 }
4683
4684 return NF_ACCEPT;
4685 }
4686
4687 static unsigned int selinux_ipv4_postroute(unsigned int hooknum,
4688 struct sk_buff *skb,
4689 const struct net_device *in,
4690 const struct net_device *out,
4691 int (*okfn)(struct sk_buff *))
4692 {
4693 return selinux_ip_postroute(skb, out->ifindex, PF_INET);
4694 }
4695
4696 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
4697 static unsigned int selinux_ipv6_postroute(unsigned int hooknum,
4698 struct sk_buff *skb,
4699 const struct net_device *in,
4700 const struct net_device *out,
4701 int (*okfn)(struct sk_buff *))
4702 {
4703 return selinux_ip_postroute(skb, out->ifindex, PF_INET6);
4704 }
4705 #endif /* IPV6 */
4706
4707 #endif /* CONFIG_NETFILTER */
4708
4709 static int selinux_netlink_send(struct sock *sk, struct sk_buff *skb)
4710 {
4711 int err;
4712
4713 err = cap_netlink_send(sk, skb);
4714 if (err)
4715 return err;
4716
4717 return selinux_nlmsg_perm(sk, skb);
4718 }
4719
4720 static int selinux_netlink_recv(struct sk_buff *skb, int capability)
4721 {
4722 int err;
4723 struct common_audit_data ad;
4724 u32 sid;
4725
4726 err = cap_netlink_recv(skb, capability);
4727 if (err)
4728 return err;
4729
4730 COMMON_AUDIT_DATA_INIT(&ad, CAP);
4731 ad.u.cap = capability;
4732
4733 security_task_getsecid(current, &sid);
4734 return avc_has_perm(sid, sid, SECCLASS_CAPABILITY,
4735 CAP_TO_MASK(capability), &ad);
4736 }
4737
4738 static int ipc_alloc_security(struct task_struct *task,
4739 struct kern_ipc_perm *perm,
4740 u16 sclass)
4741 {
4742 struct ipc_security_struct *isec;
4743 u32 sid;
4744
4745 isec = kzalloc(sizeof(struct ipc_security_struct), GFP_KERNEL);
4746 if (!isec)
4747 return -ENOMEM;
4748
4749 sid = task_sid(task);
4750 isec->sclass = sclass;
4751 isec->sid = sid;
4752 perm->security = isec;
4753
4754 return 0;
4755 }
4756
4757 static void ipc_free_security(struct kern_ipc_perm *perm)
4758 {
4759 struct ipc_security_struct *isec = perm->security;
4760 perm->security = NULL;
4761 kfree(isec);
4762 }
4763
4764 static int msg_msg_alloc_security(struct msg_msg *msg)
4765 {
4766 struct msg_security_struct *msec;
4767
4768 msec = kzalloc(sizeof(struct msg_security_struct), GFP_KERNEL);
4769 if (!msec)
4770 return -ENOMEM;
4771
4772 msec->sid = SECINITSID_UNLABELED;
4773 msg->security = msec;
4774
4775 return 0;
4776 }
4777
4778 static void msg_msg_free_security(struct msg_msg *msg)
4779 {
4780 struct msg_security_struct *msec = msg->security;
4781
4782 msg->security = NULL;
4783 kfree(msec);
4784 }
4785
4786 static int ipc_has_perm(struct kern_ipc_perm *ipc_perms,
4787 u32 perms)
4788 {
4789 struct ipc_security_struct *isec;
4790 struct common_audit_data ad;
4791 u32 sid = current_sid();
4792
4793 isec = ipc_perms->security;
4794
4795 COMMON_AUDIT_DATA_INIT(&ad, IPC);
4796 ad.u.ipc_id = ipc_perms->key;
4797
4798 return avc_has_perm(sid, isec->sid, isec->sclass, perms, &ad);
4799 }
4800
4801 static int selinux_msg_msg_alloc_security(struct msg_msg *msg)
4802 {
4803 return msg_msg_alloc_security(msg);
4804 }
4805
4806 static void selinux_msg_msg_free_security(struct msg_msg *msg)
4807 {
4808 msg_msg_free_security(msg);
4809 }
4810
4811 /* message queue security operations */
4812 static int selinux_msg_queue_alloc_security(struct msg_queue *msq)
4813 {
4814 struct ipc_security_struct *isec;
4815 struct common_audit_data ad;
4816 u32 sid = current_sid();
4817 int rc;
4818
4819 rc = ipc_alloc_security(current, &msq->q_perm, SECCLASS_MSGQ);
4820 if (rc)
4821 return rc;
4822
4823 isec = msq->q_perm.security;
4824
4825 COMMON_AUDIT_DATA_INIT(&ad, IPC);
4826 ad.u.ipc_id = msq->q_perm.key;
4827
4828 rc = avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
4829 MSGQ__CREATE, &ad);
4830 if (rc) {
4831 ipc_free_security(&msq->q_perm);
4832 return rc;
4833 }
4834 return 0;
4835 }
4836
4837 static void selinux_msg_queue_free_security(struct msg_queue *msq)
4838 {
4839 ipc_free_security(&msq->q_perm);
4840 }
4841
4842 static int selinux_msg_queue_associate(struct msg_queue *msq, int msqflg)
4843 {
4844 struct ipc_security_struct *isec;
4845 struct common_audit_data ad;
4846 u32 sid = current_sid();
4847
4848 isec = msq->q_perm.security;
4849
4850 COMMON_AUDIT_DATA_INIT(&ad, IPC);
4851 ad.u.ipc_id = msq->q_perm.key;
4852
4853 return avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
4854 MSGQ__ASSOCIATE, &ad);
4855 }
4856
4857 static int selinux_msg_queue_msgctl(struct msg_queue *msq, int cmd)
4858 {
4859 int err;
4860 int perms;
4861
4862 switch (cmd) {
4863 case IPC_INFO:
4864 case MSG_INFO:
4865 /* No specific object, just general system-wide information. */
4866 return task_has_system(current, SYSTEM__IPC_INFO);
4867 case IPC_STAT:
4868 case MSG_STAT:
4869 perms = MSGQ__GETATTR | MSGQ__ASSOCIATE;
4870 break;
4871 case IPC_SET:
4872 perms = MSGQ__SETATTR;
4873 break;
4874 case IPC_RMID:
4875 perms = MSGQ__DESTROY;
4876 break;
4877 default:
4878 return 0;
4879 }
4880
4881 err = ipc_has_perm(&msq->q_perm, perms);
4882 return err;
4883 }
4884
4885 static int selinux_msg_queue_msgsnd(struct msg_queue *msq, struct msg_msg *msg, int msqflg)
4886 {
4887 struct ipc_security_struct *isec;
4888 struct msg_security_struct *msec;
4889 struct common_audit_data ad;
4890 u32 sid = current_sid();
4891 int rc;
4892
4893 isec = msq->q_perm.security;
4894 msec = msg->security;
4895
4896 /*
4897 * First time through, need to assign label to the message
4898 */
4899 if (msec->sid == SECINITSID_UNLABELED) {
4900 /*
4901 * Compute new sid based on current process and
4902 * message queue this message will be stored in
4903 */
4904 rc = security_transition_sid(sid, isec->sid, SECCLASS_MSG,
4905 NULL, &msec->sid);
4906 if (rc)
4907 return rc;
4908 }
4909
4910 COMMON_AUDIT_DATA_INIT(&ad, IPC);
4911 ad.u.ipc_id = msq->q_perm.key;
4912
4913 /* Can this process write to the queue? */
4914 rc = avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
4915 MSGQ__WRITE, &ad);
4916 if (!rc)
4917 /* Can this process send the message */
4918 rc = avc_has_perm(sid, msec->sid, SECCLASS_MSG,
4919 MSG__SEND, &ad);
4920 if (!rc)
4921 /* Can the message be put in the queue? */
4922 rc = avc_has_perm(msec->sid, isec->sid, SECCLASS_MSGQ,
4923 MSGQ__ENQUEUE, &ad);
4924
4925 return rc;
4926 }
4927
4928 static int selinux_msg_queue_msgrcv(struct msg_queue *msq, struct msg_msg *msg,
4929 struct task_struct *target,
4930 long type, int mode)
4931 {
4932 struct ipc_security_struct *isec;
4933 struct msg_security_struct *msec;
4934 struct common_audit_data ad;
4935 u32 sid = task_sid(target);
4936 int rc;
4937
4938 isec = msq->q_perm.security;
4939 msec = msg->security;
4940
4941 COMMON_AUDIT_DATA_INIT(&ad, IPC);
4942 ad.u.ipc_id = msq->q_perm.key;
4943
4944 rc = avc_has_perm(sid, isec->sid,
4945 SECCLASS_MSGQ, MSGQ__READ, &ad);
4946 if (!rc)
4947 rc = avc_has_perm(sid, msec->sid,
4948 SECCLASS_MSG, MSG__RECEIVE, &ad);
4949 return rc;
4950 }
4951
4952 /* Shared Memory security operations */
4953 static int selinux_shm_alloc_security(struct shmid_kernel *shp)
4954 {
4955 struct ipc_security_struct *isec;
4956 struct common_audit_data ad;
4957 u32 sid = current_sid();
4958 int rc;
4959
4960 rc = ipc_alloc_security(current, &shp->shm_perm, SECCLASS_SHM);
4961 if (rc)
4962 return rc;
4963
4964 isec = shp->shm_perm.security;
4965
4966 COMMON_AUDIT_DATA_INIT(&ad, IPC);
4967 ad.u.ipc_id = shp->shm_perm.key;
4968
4969 rc = avc_has_perm(sid, isec->sid, SECCLASS_SHM,
4970 SHM__CREATE, &ad);
4971 if (rc) {
4972 ipc_free_security(&shp->shm_perm);
4973 return rc;
4974 }
4975 return 0;
4976 }
4977
4978 static void selinux_shm_free_security(struct shmid_kernel *shp)
4979 {
4980 ipc_free_security(&shp->shm_perm);
4981 }
4982
4983 static int selinux_shm_associate(struct shmid_kernel *shp, int shmflg)
4984 {
4985 struct ipc_security_struct *isec;
4986 struct common_audit_data ad;
4987 u32 sid = current_sid();
4988
4989 isec = shp->shm_perm.security;
4990
4991 COMMON_AUDIT_DATA_INIT(&ad, IPC);
4992 ad.u.ipc_id = shp->shm_perm.key;
4993
4994 return avc_has_perm(sid, isec->sid, SECCLASS_SHM,
4995 SHM__ASSOCIATE, &ad);
4996 }
4997
4998 /* Note, at this point, shp is locked down */
4999 static int selinux_shm_shmctl(struct shmid_kernel *shp, int cmd)
5000 {
5001 int perms;
5002 int err;
5003
5004 switch (cmd) {
5005 case IPC_INFO:
5006 case SHM_INFO:
5007 /* No specific object, just general system-wide information. */
5008 return task_has_system(current, SYSTEM__IPC_INFO);
5009 case IPC_STAT:
5010 case SHM_STAT:
5011 perms = SHM__GETATTR | SHM__ASSOCIATE;
5012 break;
5013 case IPC_SET:
5014 perms = SHM__SETATTR;
5015 break;
5016 case SHM_LOCK:
5017 case SHM_UNLOCK:
5018 perms = SHM__LOCK;
5019 break;
5020 case IPC_RMID:
5021 perms = SHM__DESTROY;
5022 break;
5023 default:
5024 return 0;
5025 }
5026
5027 err = ipc_has_perm(&shp->shm_perm, perms);
5028 return err;
5029 }
5030
5031 static int selinux_shm_shmat(struct shmid_kernel *shp,
5032 char __user *shmaddr, int shmflg)
5033 {
5034 u32 perms;
5035
5036 if (shmflg & SHM_RDONLY)
5037 perms = SHM__READ;
5038 else
5039 perms = SHM__READ | SHM__WRITE;
5040
5041 return ipc_has_perm(&shp->shm_perm, perms);
5042 }
5043
5044 /* Semaphore security operations */
5045 static int selinux_sem_alloc_security(struct sem_array *sma)
5046 {
5047 struct ipc_security_struct *isec;
5048 struct common_audit_data ad;
5049 u32 sid = current_sid();
5050 int rc;
5051
5052 rc = ipc_alloc_security(current, &sma->sem_perm, SECCLASS_SEM);
5053 if (rc)
5054 return rc;
5055
5056 isec = sma->sem_perm.security;
5057
5058 COMMON_AUDIT_DATA_INIT(&ad, IPC);
5059 ad.u.ipc_id = sma->sem_perm.key;
5060
5061 rc = avc_has_perm(sid, isec->sid, SECCLASS_SEM,
5062 SEM__CREATE, &ad);
5063 if (rc) {
5064 ipc_free_security(&sma->sem_perm);
5065 return rc;
5066 }
5067 return 0;
5068 }
5069
5070 static void selinux_sem_free_security(struct sem_array *sma)
5071 {
5072 ipc_free_security(&sma->sem_perm);
5073 }
5074
5075 static int selinux_sem_associate(struct sem_array *sma, int semflg)
5076 {
5077 struct ipc_security_struct *isec;
5078 struct common_audit_data ad;
5079 u32 sid = current_sid();
5080
5081 isec = sma->sem_perm.security;
5082
5083 COMMON_AUDIT_DATA_INIT(&ad, IPC);
5084 ad.u.ipc_id = sma->sem_perm.key;
5085
5086 return avc_has_perm(sid, isec->sid, SECCLASS_SEM,
5087 SEM__ASSOCIATE, &ad);
5088 }
5089
5090 /* Note, at this point, sma is locked down */
5091 static int selinux_sem_semctl(struct sem_array *sma, int cmd)
5092 {
5093 int err;
5094 u32 perms;
5095
5096 switch (cmd) {
5097 case IPC_INFO:
5098 case SEM_INFO:
5099 /* No specific object, just general system-wide information. */
5100 return task_has_system(current, SYSTEM__IPC_INFO);
5101 case GETPID:
5102 case GETNCNT:
5103 case GETZCNT:
5104 perms = SEM__GETATTR;
5105 break;
5106 case GETVAL:
5107 case GETALL:
5108 perms = SEM__READ;
5109 break;
5110 case SETVAL:
5111 case SETALL:
5112 perms = SEM__WRITE;
5113 break;
5114 case IPC_RMID:
5115 perms = SEM__DESTROY;
5116 break;
5117 case IPC_SET:
5118 perms = SEM__SETATTR;
5119 break;
5120 case IPC_STAT:
5121 case SEM_STAT:
5122 perms = SEM__GETATTR | SEM__ASSOCIATE;
5123 break;
5124 default:
5125 return 0;
5126 }
5127
5128 err = ipc_has_perm(&sma->sem_perm, perms);
5129 return err;
5130 }
5131
5132 static int selinux_sem_semop(struct sem_array *sma,
5133 struct sembuf *sops, unsigned nsops, int alter)
5134 {
5135 u32 perms;
5136
5137 if (alter)
5138 perms = SEM__READ | SEM__WRITE;
5139 else
5140 perms = SEM__READ;
5141
5142 return ipc_has_perm(&sma->sem_perm, perms);
5143 }
5144
5145 static int selinux_ipc_permission(struct kern_ipc_perm *ipcp, short flag)
5146 {
5147 u32 av = 0;
5148
5149 av = 0;
5150 if (flag & S_IRUGO)
5151 av |= IPC__UNIX_READ;
5152 if (flag & S_IWUGO)
5153 av |= IPC__UNIX_WRITE;
5154
5155 if (av == 0)
5156 return 0;
5157
5158 return ipc_has_perm(ipcp, av);
5159 }
5160
5161 static void selinux_ipc_getsecid(struct kern_ipc_perm *ipcp, u32 *secid)
5162 {
5163 struct ipc_security_struct *isec = ipcp->security;
5164 *secid = isec->sid;
5165 }
5166
5167 static void selinux_d_instantiate(struct dentry *dentry, struct inode *inode)
5168 {
5169 if (inode)
5170 inode_doinit_with_dentry(inode, dentry);
5171 }
5172
5173 static int selinux_getprocattr(struct task_struct *p,
5174 char *name, char **value)
5175 {
5176 const struct task_security_struct *__tsec;
5177 u32 sid;
5178 int error;
5179 unsigned len;
5180
5181 if (current != p) {
5182 error = current_has_perm(p, PROCESS__GETATTR);
5183 if (error)
5184 return error;
5185 }
5186
5187 rcu_read_lock();
5188 __tsec = __task_cred(p)->security;
5189
5190 if (!strcmp(name, "current"))
5191 sid = __tsec->sid;
5192 else if (!strcmp(name, "prev"))
5193 sid = __tsec->osid;
5194 else if (!strcmp(name, "exec"))
5195 sid = __tsec->exec_sid;
5196 else if (!strcmp(name, "fscreate"))
5197 sid = __tsec->create_sid;
5198 else if (!strcmp(name, "keycreate"))
5199 sid = __tsec->keycreate_sid;
5200 else if (!strcmp(name, "sockcreate"))
5201 sid = __tsec->sockcreate_sid;
5202 else
5203 goto invalid;
5204 rcu_read_unlock();
5205
5206 if (!sid)
5207 return 0;
5208
5209 error = security_sid_to_context(sid, value, &len);
5210 if (error)
5211 return error;
5212 return len;
5213
5214 invalid:
5215 rcu_read_unlock();
5216 return -EINVAL;
5217 }
5218
5219 static int selinux_setprocattr(struct task_struct *p,
5220 char *name, void *value, size_t size)
5221 {
5222 struct task_security_struct *tsec;
5223 struct task_struct *tracer;
5224 struct cred *new;
5225 u32 sid = 0, ptsid;
5226 int error;
5227 char *str = value;
5228
5229 if (current != p) {
5230 /* SELinux only allows a process to change its own
5231 security attributes. */
5232 return -EACCES;
5233 }
5234
5235 /*
5236 * Basic control over ability to set these attributes at all.
5237 * current == p, but we'll pass them separately in case the
5238 * above restriction is ever removed.
5239 */
5240 if (!strcmp(name, "exec"))
5241 error = current_has_perm(p, PROCESS__SETEXEC);
5242 else if (!strcmp(name, "fscreate"))
5243 error = current_has_perm(p, PROCESS__SETFSCREATE);
5244 else if (!strcmp(name, "keycreate"))
5245 error = current_has_perm(p, PROCESS__SETKEYCREATE);
5246 else if (!strcmp(name, "sockcreate"))
5247 error = current_has_perm(p, PROCESS__SETSOCKCREATE);
5248 else if (!strcmp(name, "current"))
5249 error = current_has_perm(p, PROCESS__SETCURRENT);
5250 else
5251 error = -EINVAL;
5252 if (error)
5253 return error;
5254
5255 /* Obtain a SID for the context, if one was specified. */
5256 if (size && str[1] && str[1] != '\n') {
5257 if (str[size-1] == '\n') {
5258 str[size-1] = 0;
5259 size--;
5260 }
5261 error = security_context_to_sid(value, size, &sid);
5262 if (error == -EINVAL && !strcmp(name, "fscreate")) {
5263 if (!capable(CAP_MAC_ADMIN))
5264 return error;
5265 error = security_context_to_sid_force(value, size,
5266 &sid);
5267 }
5268 if (error)
5269 return error;
5270 }
5271
5272 new = prepare_creds();
5273 if (!new)
5274 return -ENOMEM;
5275
5276 /* Permission checking based on the specified context is
5277 performed during the actual operation (execve,
5278 open/mkdir/...), when we know the full context of the
5279 operation. See selinux_bprm_set_creds for the execve
5280 checks and may_create for the file creation checks. The
5281 operation will then fail if the context is not permitted. */
5282 tsec = new->security;
5283 if (!strcmp(name, "exec")) {
5284 tsec->exec_sid = sid;
5285 } else if (!strcmp(name, "fscreate")) {
5286 tsec->create_sid = sid;
5287 } else if (!strcmp(name, "keycreate")) {
5288 error = may_create_key(sid, p);
5289 if (error)
5290 goto abort_change;
5291 tsec->keycreate_sid = sid;
5292 } else if (!strcmp(name, "sockcreate")) {
5293 tsec->sockcreate_sid = sid;
5294 } else if (!strcmp(name, "current")) {
5295 error = -EINVAL;
5296 if (sid == 0)
5297 goto abort_change;
5298
5299 /* Only allow single threaded processes to change context */
5300 error = -EPERM;
5301 if (!current_is_single_threaded()) {
5302 error = security_bounded_transition(tsec->sid, sid);
5303 if (error)
5304 goto abort_change;
5305 }
5306
5307 /* Check permissions for the transition. */
5308 error = avc_has_perm(tsec->sid, sid, SECCLASS_PROCESS,
5309 PROCESS__DYNTRANSITION, NULL);
5310 if (error)
5311 goto abort_change;
5312
5313 /* Check for ptracing, and update the task SID if ok.
5314 Otherwise, leave SID unchanged and fail. */
5315 ptsid = 0;
5316 task_lock(p);
5317 tracer = ptrace_parent(p);
5318 if (tracer)
5319 ptsid = task_sid(tracer);
5320 task_unlock(p);
5321
5322 if (tracer) {
5323 error = avc_has_perm(ptsid, sid, SECCLASS_PROCESS,
5324 PROCESS__PTRACE, NULL);
5325 if (error)
5326 goto abort_change;
5327 }
5328
5329 tsec->sid = sid;
5330 } else {
5331 error = -EINVAL;
5332 goto abort_change;
5333 }
5334
5335 commit_creds(new);
5336 return size;
5337
5338 abort_change:
5339 abort_creds(new);
5340 return error;
5341 }
5342
5343 static int selinux_secid_to_secctx(u32 secid, char **secdata, u32 *seclen)
5344 {
5345 return security_sid_to_context(secid, secdata, seclen);
5346 }
5347
5348 static int selinux_secctx_to_secid(const char *secdata, u32 seclen, u32 *secid)
5349 {
5350 return security_context_to_sid(secdata, seclen, secid);
5351 }
5352
5353 static void selinux_release_secctx(char *secdata, u32 seclen)
5354 {
5355 kfree(secdata);
5356 }
5357
5358 /*
5359 * called with inode->i_mutex locked
5360 */
5361 static int selinux_inode_notifysecctx(struct inode *inode, void *ctx, u32 ctxlen)
5362 {
5363 return selinux_inode_setsecurity(inode, XATTR_SELINUX_SUFFIX, ctx, ctxlen, 0);
5364 }
5365
5366 /*
5367 * called with inode->i_mutex locked
5368 */
5369 static int selinux_inode_setsecctx(struct dentry *dentry, void *ctx, u32 ctxlen)
5370 {
5371 return __vfs_setxattr_noperm(dentry, XATTR_NAME_SELINUX, ctx, ctxlen, 0);
5372 }
5373
5374 static int selinux_inode_getsecctx(struct inode *inode, void **ctx, u32 *ctxlen)
5375 {
5376 int len = 0;
5377 len = selinux_inode_getsecurity(inode, XATTR_SELINUX_SUFFIX,
5378 ctx, true);
5379 if (len < 0)
5380 return len;
5381 *ctxlen = len;
5382 return 0;
5383 }
5384 #ifdef CONFIG_KEYS
5385
5386 static int selinux_key_alloc(struct key *k, const struct cred *cred,
5387 unsigned long flags)
5388 {
5389 const struct task_security_struct *tsec;
5390 struct key_security_struct *ksec;
5391
5392 ksec = kzalloc(sizeof(struct key_security_struct), GFP_KERNEL);
5393 if (!ksec)
5394 return -ENOMEM;
5395
5396 tsec = cred->security;
5397 if (tsec->keycreate_sid)
5398 ksec->sid = tsec->keycreate_sid;
5399 else
5400 ksec->sid = tsec->sid;
5401
5402 k->security = ksec;
5403 return 0;
5404 }
5405
5406 static void selinux_key_free(struct key *k)
5407 {
5408 struct key_security_struct *ksec = k->security;
5409
5410 k->security = NULL;
5411 kfree(ksec);
5412 }
5413
5414 static int selinux_key_permission(key_ref_t key_ref,
5415 const struct cred *cred,
5416 key_perm_t perm)
5417 {
5418 struct key *key;
5419 struct key_security_struct *ksec;
5420 u32 sid;
5421
5422 /* if no specific permissions are requested, we skip the
5423 permission check. No serious, additional covert channels
5424 appear to be created. */
5425 if (perm == 0)
5426 return 0;
5427
5428 sid = cred_sid(cred);
5429
5430 key = key_ref_to_ptr(key_ref);
5431 ksec = key->security;
5432
5433 return avc_has_perm(sid, ksec->sid, SECCLASS_KEY, perm, NULL);
5434 }
5435
5436 static int selinux_key_getsecurity(struct key *key, char **_buffer)
5437 {
5438 struct key_security_struct *ksec = key->security;
5439 char *context = NULL;
5440 unsigned len;
5441 int rc;
5442
5443 rc = security_sid_to_context(ksec->sid, &context, &len);
5444 if (!rc)
5445 rc = len;
5446 *_buffer = context;
5447 return rc;
5448 }
5449
5450 #endif
5451
5452 static struct security_operations selinux_ops = {
5453 .name = "selinux",
5454
5455 .ptrace_access_check = selinux_ptrace_access_check,
5456 .ptrace_traceme = selinux_ptrace_traceme,
5457 .capget = selinux_capget,
5458 .capset = selinux_capset,
5459 .capable = selinux_capable,
5460 .quotactl = selinux_quotactl,
5461 .quota_on = selinux_quota_on,
5462 .syslog = selinux_syslog,
5463 .vm_enough_memory = selinux_vm_enough_memory,
5464
5465 .netlink_send = selinux_netlink_send,
5466 .netlink_recv = selinux_netlink_recv,
5467
5468 .bprm_set_creds = selinux_bprm_set_creds,
5469 .bprm_committing_creds = selinux_bprm_committing_creds,
5470 .bprm_committed_creds = selinux_bprm_committed_creds,
5471 .bprm_secureexec = selinux_bprm_secureexec,
5472
5473 .sb_alloc_security = selinux_sb_alloc_security,
5474 .sb_free_security = selinux_sb_free_security,
5475 .sb_copy_data = selinux_sb_copy_data,
5476 .sb_remount = selinux_sb_remount,
5477 .sb_kern_mount = selinux_sb_kern_mount,
5478 .sb_show_options = selinux_sb_show_options,
5479 .sb_statfs = selinux_sb_statfs,
5480 .sb_mount = selinux_mount,
5481 .sb_umount = selinux_umount,
5482 .sb_set_mnt_opts = selinux_set_mnt_opts,
5483 .sb_clone_mnt_opts = selinux_sb_clone_mnt_opts,
5484 .sb_parse_opts_str = selinux_parse_opts_str,
5485
5486
5487 .inode_alloc_security = selinux_inode_alloc_security,
5488 .inode_free_security = selinux_inode_free_security,
5489 .inode_init_security = selinux_inode_init_security,
5490 .inode_create = selinux_inode_create,
5491 .inode_link = selinux_inode_link,
5492 .inode_unlink = selinux_inode_unlink,
5493 .inode_symlink = selinux_inode_symlink,
5494 .inode_mkdir = selinux_inode_mkdir,
5495 .inode_rmdir = selinux_inode_rmdir,
5496 .inode_mknod = selinux_inode_mknod,
5497 .inode_rename = selinux_inode_rename,
5498 .inode_readlink = selinux_inode_readlink,
5499 .inode_follow_link = selinux_inode_follow_link,
5500 .inode_permission = selinux_inode_permission,
5501 .inode_setattr = selinux_inode_setattr,
5502 .inode_getattr = selinux_inode_getattr,
5503 .inode_setxattr = selinux_inode_setxattr,
5504 .inode_post_setxattr = selinux_inode_post_setxattr,
5505 .inode_getxattr = selinux_inode_getxattr,
5506 .inode_listxattr = selinux_inode_listxattr,
5507 .inode_removexattr = selinux_inode_removexattr,
5508 .inode_getsecurity = selinux_inode_getsecurity,
5509 .inode_setsecurity = selinux_inode_setsecurity,
5510 .inode_listsecurity = selinux_inode_listsecurity,
5511 .inode_getsecid = selinux_inode_getsecid,
5512
5513 .file_permission = selinux_file_permission,
5514 .file_alloc_security = selinux_file_alloc_security,
5515 .file_free_security = selinux_file_free_security,
5516 .file_ioctl = selinux_file_ioctl,
5517 .file_mmap = selinux_file_mmap,
5518 .file_mprotect = selinux_file_mprotect,
5519 .file_lock = selinux_file_lock,
5520 .file_fcntl = selinux_file_fcntl,
5521 .file_set_fowner = selinux_file_set_fowner,
5522 .file_send_sigiotask = selinux_file_send_sigiotask,
5523 .file_receive = selinux_file_receive,
5524
5525 .dentry_open = selinux_dentry_open,
5526
5527 .task_create = selinux_task_create,
5528 .cred_alloc_blank = selinux_cred_alloc_blank,
5529 .cred_free = selinux_cred_free,
5530 .cred_prepare = selinux_cred_prepare,
5531 .cred_transfer = selinux_cred_transfer,
5532 .kernel_act_as = selinux_kernel_act_as,
5533 .kernel_create_files_as = selinux_kernel_create_files_as,
5534 .kernel_module_request = selinux_kernel_module_request,
5535 .task_setpgid = selinux_task_setpgid,
5536 .task_getpgid = selinux_task_getpgid,
5537 .task_getsid = selinux_task_getsid,
5538 .task_getsecid = selinux_task_getsecid,
5539 .task_setnice = selinux_task_setnice,
5540 .task_setioprio = selinux_task_setioprio,
5541 .task_getioprio = selinux_task_getioprio,
5542 .task_setrlimit = selinux_task_setrlimit,
5543 .task_setscheduler = selinux_task_setscheduler,
5544 .task_getscheduler = selinux_task_getscheduler,
5545 .task_movememory = selinux_task_movememory,
5546 .task_kill = selinux_task_kill,
5547 .task_wait = selinux_task_wait,
5548 .task_to_inode = selinux_task_to_inode,
5549
5550 .ipc_permission = selinux_ipc_permission,
5551 .ipc_getsecid = selinux_ipc_getsecid,
5552
5553 .msg_msg_alloc_security = selinux_msg_msg_alloc_security,
5554 .msg_msg_free_security = selinux_msg_msg_free_security,
5555
5556 .msg_queue_alloc_security = selinux_msg_queue_alloc_security,
5557 .msg_queue_free_security = selinux_msg_queue_free_security,
5558 .msg_queue_associate = selinux_msg_queue_associate,
5559 .msg_queue_msgctl = selinux_msg_queue_msgctl,
5560 .msg_queue_msgsnd = selinux_msg_queue_msgsnd,
5561 .msg_queue_msgrcv = selinux_msg_queue_msgrcv,
5562
5563 .shm_alloc_security = selinux_shm_alloc_security,
5564 .shm_free_security = selinux_shm_free_security,
5565 .shm_associate = selinux_shm_associate,
5566 .shm_shmctl = selinux_shm_shmctl,
5567 .shm_shmat = selinux_shm_shmat,
5568
5569 .sem_alloc_security = selinux_sem_alloc_security,
5570 .sem_free_security = selinux_sem_free_security,
5571 .sem_associate = selinux_sem_associate,
5572 .sem_semctl = selinux_sem_semctl,
5573 .sem_semop = selinux_sem_semop,
5574
5575 .d_instantiate = selinux_d_instantiate,
5576
5577 .getprocattr = selinux_getprocattr,
5578 .setprocattr = selinux_setprocattr,
5579
5580 .secid_to_secctx = selinux_secid_to_secctx,
5581 .secctx_to_secid = selinux_secctx_to_secid,
5582 .release_secctx = selinux_release_secctx,
5583 .inode_notifysecctx = selinux_inode_notifysecctx,
5584 .inode_setsecctx = selinux_inode_setsecctx,
5585 .inode_getsecctx = selinux_inode_getsecctx,
5586
5587 .unix_stream_connect = selinux_socket_unix_stream_connect,
5588 .unix_may_send = selinux_socket_unix_may_send,
5589
5590 .socket_create = selinux_socket_create,
5591 .socket_post_create = selinux_socket_post_create,
5592 .socket_bind = selinux_socket_bind,
5593 .socket_connect = selinux_socket_connect,
5594 .socket_listen = selinux_socket_listen,
5595 .socket_accept = selinux_socket_accept,
5596 .socket_sendmsg = selinux_socket_sendmsg,
5597 .socket_recvmsg = selinux_socket_recvmsg,
5598 .socket_getsockname = selinux_socket_getsockname,
5599 .socket_getpeername = selinux_socket_getpeername,
5600 .socket_getsockopt = selinux_socket_getsockopt,
5601 .socket_setsockopt = selinux_socket_setsockopt,
5602 .socket_shutdown = selinux_socket_shutdown,
5603 .socket_sock_rcv_skb = selinux_socket_sock_rcv_skb,
5604 .socket_getpeersec_stream = selinux_socket_getpeersec_stream,
5605 .socket_getpeersec_dgram = selinux_socket_getpeersec_dgram,
5606 .sk_alloc_security = selinux_sk_alloc_security,
5607 .sk_free_security = selinux_sk_free_security,
5608 .sk_clone_security = selinux_sk_clone_security,
5609 .sk_getsecid = selinux_sk_getsecid,
5610 .sock_graft = selinux_sock_graft,
5611 .inet_conn_request = selinux_inet_conn_request,
5612 .inet_csk_clone = selinux_inet_csk_clone,
5613 .inet_conn_established = selinux_inet_conn_established,
5614 .secmark_relabel_packet = selinux_secmark_relabel_packet,
5615 .secmark_refcount_inc = selinux_secmark_refcount_inc,
5616 .secmark_refcount_dec = selinux_secmark_refcount_dec,
5617 .req_classify_flow = selinux_req_classify_flow,
5618 .tun_dev_create = selinux_tun_dev_create,
5619 .tun_dev_post_create = selinux_tun_dev_post_create,
5620 .tun_dev_attach = selinux_tun_dev_attach,
5621
5622 #ifdef CONFIG_SECURITY_NETWORK_XFRM
5623 .xfrm_policy_alloc_security = selinux_xfrm_policy_alloc,
5624 .xfrm_policy_clone_security = selinux_xfrm_policy_clone,
5625 .xfrm_policy_free_security = selinux_xfrm_policy_free,
5626 .xfrm_policy_delete_security = selinux_xfrm_policy_delete,
5627 .xfrm_state_alloc_security = selinux_xfrm_state_alloc,
5628 .xfrm_state_free_security = selinux_xfrm_state_free,
5629 .xfrm_state_delete_security = selinux_xfrm_state_delete,
5630 .xfrm_policy_lookup = selinux_xfrm_policy_lookup,
5631 .xfrm_state_pol_flow_match = selinux_xfrm_state_pol_flow_match,
5632 .xfrm_decode_session = selinux_xfrm_decode_session,
5633 #endif
5634
5635 #ifdef CONFIG_KEYS
5636 .key_alloc = selinux_key_alloc,
5637 .key_free = selinux_key_free,
5638 .key_permission = selinux_key_permission,
5639 .key_getsecurity = selinux_key_getsecurity,
5640 #endif
5641
5642 #ifdef CONFIG_AUDIT
5643 .audit_rule_init = selinux_audit_rule_init,
5644 .audit_rule_known = selinux_audit_rule_known,
5645 .audit_rule_match = selinux_audit_rule_match,
5646 .audit_rule_free = selinux_audit_rule_free,
5647 #endif
5648 };
5649
5650 static __init int selinux_init(void)
5651 {
5652 if (!security_module_enable(&selinux_ops)) {
5653 selinux_enabled = 0;
5654 return 0;
5655 }
5656
5657 if (!selinux_enabled) {
5658 printk(KERN_INFO "SELinux: Disabled at boot.\n");
5659 return 0;
5660 }
5661
5662 printk(KERN_INFO "SELinux: Initializing.\n");
5663
5664 /* Set the security state for the initial task. */
5665 cred_init_security();
5666
5667 default_noexec = !(VM_DATA_DEFAULT_FLAGS & VM_EXEC);
5668
5669 sel_inode_cache = kmem_cache_create("selinux_inode_security",
5670 sizeof(struct inode_security_struct),
5671 0, SLAB_PANIC, NULL);
5672 avc_init();
5673
5674 if (register_security(&selinux_ops))
5675 panic("SELinux: Unable to register with kernel.\n");
5676
5677 if (selinux_enforcing)
5678 printk(KERN_DEBUG "SELinux: Starting in enforcing mode\n");
5679 else
5680 printk(KERN_DEBUG "SELinux: Starting in permissive mode\n");
5681
5682 return 0;
5683 }
5684
5685 static void delayed_superblock_init(struct super_block *sb, void *unused)
5686 {
5687 superblock_doinit(sb, NULL);
5688 }
5689
5690 void selinux_complete_init(void)
5691 {
5692 printk(KERN_DEBUG "SELinux: Completing initialization.\n");
5693
5694 /* Set up any superblocks initialized prior to the policy load. */
5695 printk(KERN_DEBUG "SELinux: Setting up existing superblocks.\n");
5696 iterate_supers(delayed_superblock_init, NULL);
5697 }
5698
5699 /* SELinux requires early initialization in order to label
5700 all processes and objects when they are created. */
5701 security_initcall(selinux_init);
5702
5703 #if defined(CONFIG_NETFILTER)
5704
5705 static struct nf_hook_ops selinux_ipv4_ops[] = {
5706 {
5707 .hook = selinux_ipv4_postroute,
5708 .owner = THIS_MODULE,
5709 .pf = PF_INET,
5710 .hooknum = NF_INET_POST_ROUTING,
5711 .priority = NF_IP_PRI_SELINUX_LAST,
5712 },
5713 {
5714 .hook = selinux_ipv4_forward,
5715 .owner = THIS_MODULE,
5716 .pf = PF_INET,
5717 .hooknum = NF_INET_FORWARD,
5718 .priority = NF_IP_PRI_SELINUX_FIRST,
5719 },
5720 {
5721 .hook = selinux_ipv4_output,
5722 .owner = THIS_MODULE,
5723 .pf = PF_INET,
5724 .hooknum = NF_INET_LOCAL_OUT,
5725 .priority = NF_IP_PRI_SELINUX_FIRST,
5726 }
5727 };
5728
5729 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
5730
5731 static struct nf_hook_ops selinux_ipv6_ops[] = {
5732 {
5733 .hook = selinux_ipv6_postroute,
5734 .owner = THIS_MODULE,
5735 .pf = PF_INET6,
5736 .hooknum = NF_INET_POST_ROUTING,
5737 .priority = NF_IP6_PRI_SELINUX_LAST,
5738 },
5739 {
5740 .hook = selinux_ipv6_forward,
5741 .owner = THIS_MODULE,
5742 .pf = PF_INET6,
5743 .hooknum = NF_INET_FORWARD,
5744 .priority = NF_IP6_PRI_SELINUX_FIRST,
5745 }
5746 };
5747
5748 #endif /* IPV6 */
5749
5750 static int __init selinux_nf_ip_init(void)
5751 {
5752 int err = 0;
5753
5754 if (!selinux_enabled)
5755 goto out;
5756
5757 printk(KERN_DEBUG "SELinux: Registering netfilter hooks\n");
5758
5759 err = nf_register_hooks(selinux_ipv4_ops, ARRAY_SIZE(selinux_ipv4_ops));
5760 if (err)
5761 panic("SELinux: nf_register_hooks for IPv4: error %d\n", err);
5762
5763 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
5764 err = nf_register_hooks(selinux_ipv6_ops, ARRAY_SIZE(selinux_ipv6_ops));
5765 if (err)
5766 panic("SELinux: nf_register_hooks for IPv6: error %d\n", err);
5767 #endif /* IPV6 */
5768
5769 out:
5770 return err;
5771 }
5772
5773 __initcall(selinux_nf_ip_init);
5774
5775 #ifdef CONFIG_SECURITY_SELINUX_DISABLE
5776 static void selinux_nf_ip_exit(void)
5777 {
5778 printk(KERN_DEBUG "SELinux: Unregistering netfilter hooks\n");
5779
5780 nf_unregister_hooks(selinux_ipv4_ops, ARRAY_SIZE(selinux_ipv4_ops));
5781 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
5782 nf_unregister_hooks(selinux_ipv6_ops, ARRAY_SIZE(selinux_ipv6_ops));
5783 #endif /* IPV6 */
5784 }
5785 #endif
5786
5787 #else /* CONFIG_NETFILTER */
5788
5789 #ifdef CONFIG_SECURITY_SELINUX_DISABLE
5790 #define selinux_nf_ip_exit()
5791 #endif
5792
5793 #endif /* CONFIG_NETFILTER */
5794
5795 #ifdef CONFIG_SECURITY_SELINUX_DISABLE
5796 static int selinux_disabled;
5797
5798 int selinux_disable(void)
5799 {
5800 if (ss_initialized) {
5801 /* Not permitted after initial policy load. */
5802 return -EINVAL;
5803 }
5804
5805 if (selinux_disabled) {
5806 /* Only do this once. */
5807 return -EINVAL;
5808 }
5809
5810 printk(KERN_INFO "SELinux: Disabled at runtime.\n");
5811
5812 selinux_disabled = 1;
5813 selinux_enabled = 0;
5814
5815 reset_security_ops();
5816
5817 /* Try to destroy the avc node cache */
5818 avc_disable();
5819
5820 /* Unregister netfilter hooks. */
5821 selinux_nf_ip_exit();
5822
5823 /* Unregister selinuxfs. */
5824 exit_sel_fs();
5825
5826 return 0;
5827 }
5828 #endif