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atomic: use <linux/atomic.h>
[mirror_ubuntu-zesty-kernel.git] / security / selinux / hooks.c
1 /*
2 * NSA Security-Enhanced Linux (SELinux) security module
3 *
4 * This file contains the SELinux hook function implementations.
5 *
6 * Authors: Stephen Smalley, <sds@epoch.ncsc.mil>
7 * Chris Vance, <cvance@nai.com>
8 * Wayne Salamon, <wsalamon@nai.com>
9 * James Morris <jmorris@redhat.com>
10 *
11 * Copyright (C) 2001,2002 Networks Associates Technology, Inc.
12 * Copyright (C) 2003-2008 Red Hat, Inc., James Morris <jmorris@redhat.com>
13 * Eric Paris <eparis@redhat.com>
14 * Copyright (C) 2004-2005 Trusted Computer Solutions, Inc.
15 * <dgoeddel@trustedcs.com>
16 * Copyright (C) 2006, 2007, 2009 Hewlett-Packard Development Company, L.P.
17 * Paul Moore <paul.moore@hp.com>
18 * Copyright (C) 2007 Hitachi Software Engineering Co., Ltd.
19 * Yuichi Nakamura <ynakam@hitachisoft.jp>
20 *
21 * This program is free software; you can redistribute it and/or modify
22 * it under the terms of the GNU General Public License version 2,
23 * as published by the Free Software Foundation.
24 */
25
26 #include <linux/init.h>
27 #include <linux/kd.h>
28 #include <linux/kernel.h>
29 #include <linux/tracehook.h>
30 #include <linux/errno.h>
31 #include <linux/ext2_fs.h>
32 #include <linux/sched.h>
33 #include <linux/security.h>
34 #include <linux/xattr.h>
35 #include <linux/capability.h>
36 #include <linux/unistd.h>
37 #include <linux/mm.h>
38 #include <linux/mman.h>
39 #include <linux/slab.h>
40 #include <linux/pagemap.h>
41 #include <linux/proc_fs.h>
42 #include <linux/swap.h>
43 #include <linux/spinlock.h>
44 #include <linux/syscalls.h>
45 #include <linux/dcache.h>
46 #include <linux/file.h>
47 #include <linux/fdtable.h>
48 #include <linux/namei.h>
49 #include <linux/mount.h>
50 #include <linux/netfilter_ipv4.h>
51 #include <linux/netfilter_ipv6.h>
52 #include <linux/tty.h>
53 #include <net/icmp.h>
54 #include <net/ip.h> /* for local_port_range[] */
55 #include <net/tcp.h> /* struct or_callable used in sock_rcv_skb */
56 #include <net/net_namespace.h>
57 #include <net/netlabel.h>
58 #include <linux/uaccess.h>
59 #include <asm/ioctls.h>
60 #include <linux/atomic.h>
61 #include <linux/bitops.h>
62 #include <linux/interrupt.h>
63 #include <linux/netdevice.h> /* for network interface checks */
64 #include <linux/netlink.h>
65 #include <linux/tcp.h>
66 #include <linux/udp.h>
67 #include <linux/dccp.h>
68 #include <linux/quota.h>
69 #include <linux/un.h> /* for Unix socket types */
70 #include <net/af_unix.h> /* for Unix socket types */
71 #include <linux/parser.h>
72 #include <linux/nfs_mount.h>
73 #include <net/ipv6.h>
74 #include <linux/hugetlb.h>
75 #include <linux/personality.h>
76 #include <linux/audit.h>
77 #include <linux/string.h>
78 #include <linux/selinux.h>
79 #include <linux/mutex.h>
80 #include <linux/posix-timers.h>
81 #include <linux/syslog.h>
82 #include <linux/user_namespace.h>
83
84 #include "avc.h"
85 #include "objsec.h"
86 #include "netif.h"
87 #include "netnode.h"
88 #include "netport.h"
89 #include "xfrm.h"
90 #include "netlabel.h"
91 #include "audit.h"
92
93 #define NUM_SEL_MNT_OPTS 5
94
95 extern int selinux_nlmsg_lookup(u16 sclass, u16 nlmsg_type, u32 *perm);
96 extern struct security_operations *security_ops;
97
98 /* SECMARK reference count */
99 atomic_t selinux_secmark_refcount = ATOMIC_INIT(0);
100
101 #ifdef CONFIG_SECURITY_SELINUX_DEVELOP
102 int selinux_enforcing;
103
104 static int __init enforcing_setup(char *str)
105 {
106 unsigned long enforcing;
107 if (!strict_strtoul(str, 0, &enforcing))
108 selinux_enforcing = enforcing ? 1 : 0;
109 return 1;
110 }
111 __setup("enforcing=", enforcing_setup);
112 #endif
113
114 #ifdef CONFIG_SECURITY_SELINUX_BOOTPARAM
115 int selinux_enabled = CONFIG_SECURITY_SELINUX_BOOTPARAM_VALUE;
116
117 static int __init selinux_enabled_setup(char *str)
118 {
119 unsigned long enabled;
120 if (!strict_strtoul(str, 0, &enabled))
121 selinux_enabled = enabled ? 1 : 0;
122 return 1;
123 }
124 __setup("selinux=", selinux_enabled_setup);
125 #else
126 int selinux_enabled = 1;
127 #endif
128
129 static struct kmem_cache *sel_inode_cache;
130
131 /**
132 * selinux_secmark_enabled - Check to see if SECMARK is currently enabled
133 *
134 * Description:
135 * This function checks the SECMARK reference counter to see if any SECMARK
136 * targets are currently configured, if the reference counter is greater than
137 * zero SECMARK is considered to be enabled. Returns true (1) if SECMARK is
138 * enabled, false (0) if SECMARK is disabled.
139 *
140 */
141 static int selinux_secmark_enabled(void)
142 {
143 return (atomic_read(&selinux_secmark_refcount) > 0);
144 }
145
146 /*
147 * initialise the security for the init task
148 */
149 static void cred_init_security(void)
150 {
151 struct cred *cred = (struct cred *) current->real_cred;
152 struct task_security_struct *tsec;
153
154 tsec = kzalloc(sizeof(struct task_security_struct), GFP_KERNEL);
155 if (!tsec)
156 panic("SELinux: Failed to initialize initial task.\n");
157
158 tsec->osid = tsec->sid = SECINITSID_KERNEL;
159 cred->security = tsec;
160 }
161
162 /*
163 * get the security ID of a set of credentials
164 */
165 static inline u32 cred_sid(const struct cred *cred)
166 {
167 const struct task_security_struct *tsec;
168
169 tsec = cred->security;
170 return tsec->sid;
171 }
172
173 /*
174 * get the objective security ID of a task
175 */
176 static inline u32 task_sid(const struct task_struct *task)
177 {
178 u32 sid;
179
180 rcu_read_lock();
181 sid = cred_sid(__task_cred(task));
182 rcu_read_unlock();
183 return sid;
184 }
185
186 /*
187 * get the subjective security ID of the current task
188 */
189 static inline u32 current_sid(void)
190 {
191 const struct task_security_struct *tsec = current_security();
192
193 return tsec->sid;
194 }
195
196 /* Allocate and free functions for each kind of security blob. */
197
198 static int inode_alloc_security(struct inode *inode)
199 {
200 struct inode_security_struct *isec;
201 u32 sid = current_sid();
202
203 isec = kmem_cache_zalloc(sel_inode_cache, GFP_NOFS);
204 if (!isec)
205 return -ENOMEM;
206
207 mutex_init(&isec->lock);
208 INIT_LIST_HEAD(&isec->list);
209 isec->inode = inode;
210 isec->sid = SECINITSID_UNLABELED;
211 isec->sclass = SECCLASS_FILE;
212 isec->task_sid = sid;
213 inode->i_security = isec;
214
215 return 0;
216 }
217
218 static void inode_free_security(struct inode *inode)
219 {
220 struct inode_security_struct *isec = inode->i_security;
221 struct superblock_security_struct *sbsec = inode->i_sb->s_security;
222
223 spin_lock(&sbsec->isec_lock);
224 if (!list_empty(&isec->list))
225 list_del_init(&isec->list);
226 spin_unlock(&sbsec->isec_lock);
227
228 inode->i_security = NULL;
229 kmem_cache_free(sel_inode_cache, isec);
230 }
231
232 static int file_alloc_security(struct file *file)
233 {
234 struct file_security_struct *fsec;
235 u32 sid = current_sid();
236
237 fsec = kzalloc(sizeof(struct file_security_struct), GFP_KERNEL);
238 if (!fsec)
239 return -ENOMEM;
240
241 fsec->sid = sid;
242 fsec->fown_sid = sid;
243 file->f_security = fsec;
244
245 return 0;
246 }
247
248 static void file_free_security(struct file *file)
249 {
250 struct file_security_struct *fsec = file->f_security;
251 file->f_security = NULL;
252 kfree(fsec);
253 }
254
255 static int superblock_alloc_security(struct super_block *sb)
256 {
257 struct superblock_security_struct *sbsec;
258
259 sbsec = kzalloc(sizeof(struct superblock_security_struct), GFP_KERNEL);
260 if (!sbsec)
261 return -ENOMEM;
262
263 mutex_init(&sbsec->lock);
264 INIT_LIST_HEAD(&sbsec->isec_head);
265 spin_lock_init(&sbsec->isec_lock);
266 sbsec->sb = sb;
267 sbsec->sid = SECINITSID_UNLABELED;
268 sbsec->def_sid = SECINITSID_FILE;
269 sbsec->mntpoint_sid = SECINITSID_UNLABELED;
270 sb->s_security = sbsec;
271
272 return 0;
273 }
274
275 static void superblock_free_security(struct super_block *sb)
276 {
277 struct superblock_security_struct *sbsec = sb->s_security;
278 sb->s_security = NULL;
279 kfree(sbsec);
280 }
281
282 /* The security server must be initialized before
283 any labeling or access decisions can be provided. */
284 extern int ss_initialized;
285
286 /* The file system's label must be initialized prior to use. */
287
288 static const char *labeling_behaviors[6] = {
289 "uses xattr",
290 "uses transition SIDs",
291 "uses task SIDs",
292 "uses genfs_contexts",
293 "not configured for labeling",
294 "uses mountpoint labeling",
295 };
296
297 static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dentry);
298
299 static inline int inode_doinit(struct inode *inode)
300 {
301 return inode_doinit_with_dentry(inode, NULL);
302 }
303
304 enum {
305 Opt_error = -1,
306 Opt_context = 1,
307 Opt_fscontext = 2,
308 Opt_defcontext = 3,
309 Opt_rootcontext = 4,
310 Opt_labelsupport = 5,
311 };
312
313 static const match_table_t tokens = {
314 {Opt_context, CONTEXT_STR "%s"},
315 {Opt_fscontext, FSCONTEXT_STR "%s"},
316 {Opt_defcontext, DEFCONTEXT_STR "%s"},
317 {Opt_rootcontext, ROOTCONTEXT_STR "%s"},
318 {Opt_labelsupport, LABELSUPP_STR},
319 {Opt_error, NULL},
320 };
321
322 #define SEL_MOUNT_FAIL_MSG "SELinux: duplicate or incompatible mount options\n"
323
324 static int may_context_mount_sb_relabel(u32 sid,
325 struct superblock_security_struct *sbsec,
326 const struct cred *cred)
327 {
328 const struct task_security_struct *tsec = cred->security;
329 int rc;
330
331 rc = avc_has_perm(tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM,
332 FILESYSTEM__RELABELFROM, NULL);
333 if (rc)
334 return rc;
335
336 rc = avc_has_perm(tsec->sid, sid, SECCLASS_FILESYSTEM,
337 FILESYSTEM__RELABELTO, NULL);
338 return rc;
339 }
340
341 static int may_context_mount_inode_relabel(u32 sid,
342 struct superblock_security_struct *sbsec,
343 const struct cred *cred)
344 {
345 const struct task_security_struct *tsec = cred->security;
346 int rc;
347 rc = avc_has_perm(tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM,
348 FILESYSTEM__RELABELFROM, NULL);
349 if (rc)
350 return rc;
351
352 rc = avc_has_perm(sid, sbsec->sid, SECCLASS_FILESYSTEM,
353 FILESYSTEM__ASSOCIATE, NULL);
354 return rc;
355 }
356
357 static int sb_finish_set_opts(struct super_block *sb)
358 {
359 struct superblock_security_struct *sbsec = sb->s_security;
360 struct dentry *root = sb->s_root;
361 struct inode *root_inode = root->d_inode;
362 int rc = 0;
363
364 if (sbsec->behavior == SECURITY_FS_USE_XATTR) {
365 /* Make sure that the xattr handler exists and that no
366 error other than -ENODATA is returned by getxattr on
367 the root directory. -ENODATA is ok, as this may be
368 the first boot of the SELinux kernel before we have
369 assigned xattr values to the filesystem. */
370 if (!root_inode->i_op->getxattr) {
371 printk(KERN_WARNING "SELinux: (dev %s, type %s) has no "
372 "xattr support\n", sb->s_id, sb->s_type->name);
373 rc = -EOPNOTSUPP;
374 goto out;
375 }
376 rc = root_inode->i_op->getxattr(root, XATTR_NAME_SELINUX, NULL, 0);
377 if (rc < 0 && rc != -ENODATA) {
378 if (rc == -EOPNOTSUPP)
379 printk(KERN_WARNING "SELinux: (dev %s, type "
380 "%s) has no security xattr handler\n",
381 sb->s_id, sb->s_type->name);
382 else
383 printk(KERN_WARNING "SELinux: (dev %s, type "
384 "%s) getxattr errno %d\n", sb->s_id,
385 sb->s_type->name, -rc);
386 goto out;
387 }
388 }
389
390 sbsec->flags |= (SE_SBINITIALIZED | SE_SBLABELSUPP);
391
392 if (sbsec->behavior > ARRAY_SIZE(labeling_behaviors))
393 printk(KERN_ERR "SELinux: initialized (dev %s, type %s), unknown behavior\n",
394 sb->s_id, sb->s_type->name);
395 else
396 printk(KERN_DEBUG "SELinux: initialized (dev %s, type %s), %s\n",
397 sb->s_id, sb->s_type->name,
398 labeling_behaviors[sbsec->behavior-1]);
399
400 if (sbsec->behavior == SECURITY_FS_USE_GENFS ||
401 sbsec->behavior == SECURITY_FS_USE_MNTPOINT ||
402 sbsec->behavior == SECURITY_FS_USE_NONE ||
403 sbsec->behavior > ARRAY_SIZE(labeling_behaviors))
404 sbsec->flags &= ~SE_SBLABELSUPP;
405
406 /* Special handling for sysfs. Is genfs but also has setxattr handler*/
407 if (strncmp(sb->s_type->name, "sysfs", sizeof("sysfs")) == 0)
408 sbsec->flags |= SE_SBLABELSUPP;
409
410 /* Initialize the root inode. */
411 rc = inode_doinit_with_dentry(root_inode, root);
412
413 /* Initialize any other inodes associated with the superblock, e.g.
414 inodes created prior to initial policy load or inodes created
415 during get_sb by a pseudo filesystem that directly
416 populates itself. */
417 spin_lock(&sbsec->isec_lock);
418 next_inode:
419 if (!list_empty(&sbsec->isec_head)) {
420 struct inode_security_struct *isec =
421 list_entry(sbsec->isec_head.next,
422 struct inode_security_struct, list);
423 struct inode *inode = isec->inode;
424 spin_unlock(&sbsec->isec_lock);
425 inode = igrab(inode);
426 if (inode) {
427 if (!IS_PRIVATE(inode))
428 inode_doinit(inode);
429 iput(inode);
430 }
431 spin_lock(&sbsec->isec_lock);
432 list_del_init(&isec->list);
433 goto next_inode;
434 }
435 spin_unlock(&sbsec->isec_lock);
436 out:
437 return rc;
438 }
439
440 /*
441 * This function should allow an FS to ask what it's mount security
442 * options were so it can use those later for submounts, displaying
443 * mount options, or whatever.
444 */
445 static int selinux_get_mnt_opts(const struct super_block *sb,
446 struct security_mnt_opts *opts)
447 {
448 int rc = 0, i;
449 struct superblock_security_struct *sbsec = sb->s_security;
450 char *context = NULL;
451 u32 len;
452 char tmp;
453
454 security_init_mnt_opts(opts);
455
456 if (!(sbsec->flags & SE_SBINITIALIZED))
457 return -EINVAL;
458
459 if (!ss_initialized)
460 return -EINVAL;
461
462 tmp = sbsec->flags & SE_MNTMASK;
463 /* count the number of mount options for this sb */
464 for (i = 0; i < 8; i++) {
465 if (tmp & 0x01)
466 opts->num_mnt_opts++;
467 tmp >>= 1;
468 }
469 /* Check if the Label support flag is set */
470 if (sbsec->flags & SE_SBLABELSUPP)
471 opts->num_mnt_opts++;
472
473 opts->mnt_opts = kcalloc(opts->num_mnt_opts, sizeof(char *), GFP_ATOMIC);
474 if (!opts->mnt_opts) {
475 rc = -ENOMEM;
476 goto out_free;
477 }
478
479 opts->mnt_opts_flags = kcalloc(opts->num_mnt_opts, sizeof(int), GFP_ATOMIC);
480 if (!opts->mnt_opts_flags) {
481 rc = -ENOMEM;
482 goto out_free;
483 }
484
485 i = 0;
486 if (sbsec->flags & FSCONTEXT_MNT) {
487 rc = security_sid_to_context(sbsec->sid, &context, &len);
488 if (rc)
489 goto out_free;
490 opts->mnt_opts[i] = context;
491 opts->mnt_opts_flags[i++] = FSCONTEXT_MNT;
492 }
493 if (sbsec->flags & CONTEXT_MNT) {
494 rc = security_sid_to_context(sbsec->mntpoint_sid, &context, &len);
495 if (rc)
496 goto out_free;
497 opts->mnt_opts[i] = context;
498 opts->mnt_opts_flags[i++] = CONTEXT_MNT;
499 }
500 if (sbsec->flags & DEFCONTEXT_MNT) {
501 rc = security_sid_to_context(sbsec->def_sid, &context, &len);
502 if (rc)
503 goto out_free;
504 opts->mnt_opts[i] = context;
505 opts->mnt_opts_flags[i++] = DEFCONTEXT_MNT;
506 }
507 if (sbsec->flags & ROOTCONTEXT_MNT) {
508 struct inode *root = sbsec->sb->s_root->d_inode;
509 struct inode_security_struct *isec = root->i_security;
510
511 rc = security_sid_to_context(isec->sid, &context, &len);
512 if (rc)
513 goto out_free;
514 opts->mnt_opts[i] = context;
515 opts->mnt_opts_flags[i++] = ROOTCONTEXT_MNT;
516 }
517 if (sbsec->flags & SE_SBLABELSUPP) {
518 opts->mnt_opts[i] = NULL;
519 opts->mnt_opts_flags[i++] = SE_SBLABELSUPP;
520 }
521
522 BUG_ON(i != opts->num_mnt_opts);
523
524 return 0;
525
526 out_free:
527 security_free_mnt_opts(opts);
528 return rc;
529 }
530
531 static int bad_option(struct superblock_security_struct *sbsec, char flag,
532 u32 old_sid, u32 new_sid)
533 {
534 char mnt_flags = sbsec->flags & SE_MNTMASK;
535
536 /* check if the old mount command had the same options */
537 if (sbsec->flags & SE_SBINITIALIZED)
538 if (!(sbsec->flags & flag) ||
539 (old_sid != new_sid))
540 return 1;
541
542 /* check if we were passed the same options twice,
543 * aka someone passed context=a,context=b
544 */
545 if (!(sbsec->flags & SE_SBINITIALIZED))
546 if (mnt_flags & flag)
547 return 1;
548 return 0;
549 }
550
551 /*
552 * Allow filesystems with binary mount data to explicitly set mount point
553 * labeling information.
554 */
555 static int selinux_set_mnt_opts(struct super_block *sb,
556 struct security_mnt_opts *opts)
557 {
558 const struct cred *cred = current_cred();
559 int rc = 0, i;
560 struct superblock_security_struct *sbsec = sb->s_security;
561 const char *name = sb->s_type->name;
562 struct inode *inode = sbsec->sb->s_root->d_inode;
563 struct inode_security_struct *root_isec = inode->i_security;
564 u32 fscontext_sid = 0, context_sid = 0, rootcontext_sid = 0;
565 u32 defcontext_sid = 0;
566 char **mount_options = opts->mnt_opts;
567 int *flags = opts->mnt_opts_flags;
568 int num_opts = opts->num_mnt_opts;
569
570 mutex_lock(&sbsec->lock);
571
572 if (!ss_initialized) {
573 if (!num_opts) {
574 /* Defer initialization until selinux_complete_init,
575 after the initial policy is loaded and the security
576 server is ready to handle calls. */
577 goto out;
578 }
579 rc = -EINVAL;
580 printk(KERN_WARNING "SELinux: Unable to set superblock options "
581 "before the security server is initialized\n");
582 goto out;
583 }
584
585 /*
586 * Binary mount data FS will come through this function twice. Once
587 * from an explicit call and once from the generic calls from the vfs.
588 * Since the generic VFS calls will not contain any security mount data
589 * we need to skip the double mount verification.
590 *
591 * This does open a hole in which we will not notice if the first
592 * mount using this sb set explict options and a second mount using
593 * this sb does not set any security options. (The first options
594 * will be used for both mounts)
595 */
596 if ((sbsec->flags & SE_SBINITIALIZED) && (sb->s_type->fs_flags & FS_BINARY_MOUNTDATA)
597 && (num_opts == 0))
598 goto out;
599
600 /*
601 * parse the mount options, check if they are valid sids.
602 * also check if someone is trying to mount the same sb more
603 * than once with different security options.
604 */
605 for (i = 0; i < num_opts; i++) {
606 u32 sid;
607
608 if (flags[i] == SE_SBLABELSUPP)
609 continue;
610 rc = security_context_to_sid(mount_options[i],
611 strlen(mount_options[i]), &sid);
612 if (rc) {
613 printk(KERN_WARNING "SELinux: security_context_to_sid"
614 "(%s) failed for (dev %s, type %s) errno=%d\n",
615 mount_options[i], sb->s_id, name, rc);
616 goto out;
617 }
618 switch (flags[i]) {
619 case FSCONTEXT_MNT:
620 fscontext_sid = sid;
621
622 if (bad_option(sbsec, FSCONTEXT_MNT, sbsec->sid,
623 fscontext_sid))
624 goto out_double_mount;
625
626 sbsec->flags |= FSCONTEXT_MNT;
627 break;
628 case CONTEXT_MNT:
629 context_sid = sid;
630
631 if (bad_option(sbsec, CONTEXT_MNT, sbsec->mntpoint_sid,
632 context_sid))
633 goto out_double_mount;
634
635 sbsec->flags |= CONTEXT_MNT;
636 break;
637 case ROOTCONTEXT_MNT:
638 rootcontext_sid = sid;
639
640 if (bad_option(sbsec, ROOTCONTEXT_MNT, root_isec->sid,
641 rootcontext_sid))
642 goto out_double_mount;
643
644 sbsec->flags |= ROOTCONTEXT_MNT;
645
646 break;
647 case DEFCONTEXT_MNT:
648 defcontext_sid = sid;
649
650 if (bad_option(sbsec, DEFCONTEXT_MNT, sbsec->def_sid,
651 defcontext_sid))
652 goto out_double_mount;
653
654 sbsec->flags |= DEFCONTEXT_MNT;
655
656 break;
657 default:
658 rc = -EINVAL;
659 goto out;
660 }
661 }
662
663 if (sbsec->flags & SE_SBINITIALIZED) {
664 /* previously mounted with options, but not on this attempt? */
665 if ((sbsec->flags & SE_MNTMASK) && !num_opts)
666 goto out_double_mount;
667 rc = 0;
668 goto out;
669 }
670
671 if (strcmp(sb->s_type->name, "proc") == 0)
672 sbsec->flags |= SE_SBPROC;
673
674 /* Determine the labeling behavior to use for this filesystem type. */
675 rc = security_fs_use((sbsec->flags & SE_SBPROC) ? "proc" : sb->s_type->name, &sbsec->behavior, &sbsec->sid);
676 if (rc) {
677 printk(KERN_WARNING "%s: security_fs_use(%s) returned %d\n",
678 __func__, sb->s_type->name, rc);
679 goto out;
680 }
681
682 /* sets the context of the superblock for the fs being mounted. */
683 if (fscontext_sid) {
684 rc = may_context_mount_sb_relabel(fscontext_sid, sbsec, cred);
685 if (rc)
686 goto out;
687
688 sbsec->sid = fscontext_sid;
689 }
690
691 /*
692 * Switch to using mount point labeling behavior.
693 * sets the label used on all file below the mountpoint, and will set
694 * the superblock context if not already set.
695 */
696 if (context_sid) {
697 if (!fscontext_sid) {
698 rc = may_context_mount_sb_relabel(context_sid, sbsec,
699 cred);
700 if (rc)
701 goto out;
702 sbsec->sid = context_sid;
703 } else {
704 rc = may_context_mount_inode_relabel(context_sid, sbsec,
705 cred);
706 if (rc)
707 goto out;
708 }
709 if (!rootcontext_sid)
710 rootcontext_sid = context_sid;
711
712 sbsec->mntpoint_sid = context_sid;
713 sbsec->behavior = SECURITY_FS_USE_MNTPOINT;
714 }
715
716 if (rootcontext_sid) {
717 rc = may_context_mount_inode_relabel(rootcontext_sid, sbsec,
718 cred);
719 if (rc)
720 goto out;
721
722 root_isec->sid = rootcontext_sid;
723 root_isec->initialized = 1;
724 }
725
726 if (defcontext_sid) {
727 if (sbsec->behavior != SECURITY_FS_USE_XATTR) {
728 rc = -EINVAL;
729 printk(KERN_WARNING "SELinux: defcontext option is "
730 "invalid for this filesystem type\n");
731 goto out;
732 }
733
734 if (defcontext_sid != sbsec->def_sid) {
735 rc = may_context_mount_inode_relabel(defcontext_sid,
736 sbsec, cred);
737 if (rc)
738 goto out;
739 }
740
741 sbsec->def_sid = defcontext_sid;
742 }
743
744 rc = sb_finish_set_opts(sb);
745 out:
746 mutex_unlock(&sbsec->lock);
747 return rc;
748 out_double_mount:
749 rc = -EINVAL;
750 printk(KERN_WARNING "SELinux: mount invalid. Same superblock, different "
751 "security settings for (dev %s, type %s)\n", sb->s_id, name);
752 goto out;
753 }
754
755 static void selinux_sb_clone_mnt_opts(const struct super_block *oldsb,
756 struct super_block *newsb)
757 {
758 const struct superblock_security_struct *oldsbsec = oldsb->s_security;
759 struct superblock_security_struct *newsbsec = newsb->s_security;
760
761 int set_fscontext = (oldsbsec->flags & FSCONTEXT_MNT);
762 int set_context = (oldsbsec->flags & CONTEXT_MNT);
763 int set_rootcontext = (oldsbsec->flags & ROOTCONTEXT_MNT);
764
765 /*
766 * if the parent was able to be mounted it clearly had no special lsm
767 * mount options. thus we can safely deal with this superblock later
768 */
769 if (!ss_initialized)
770 return;
771
772 /* how can we clone if the old one wasn't set up?? */
773 BUG_ON(!(oldsbsec->flags & SE_SBINITIALIZED));
774
775 /* if fs is reusing a sb, just let its options stand... */
776 if (newsbsec->flags & SE_SBINITIALIZED)
777 return;
778
779 mutex_lock(&newsbsec->lock);
780
781 newsbsec->flags = oldsbsec->flags;
782
783 newsbsec->sid = oldsbsec->sid;
784 newsbsec->def_sid = oldsbsec->def_sid;
785 newsbsec->behavior = oldsbsec->behavior;
786
787 if (set_context) {
788 u32 sid = oldsbsec->mntpoint_sid;
789
790 if (!set_fscontext)
791 newsbsec->sid = sid;
792 if (!set_rootcontext) {
793 struct inode *newinode = newsb->s_root->d_inode;
794 struct inode_security_struct *newisec = newinode->i_security;
795 newisec->sid = sid;
796 }
797 newsbsec->mntpoint_sid = sid;
798 }
799 if (set_rootcontext) {
800 const struct inode *oldinode = oldsb->s_root->d_inode;
801 const struct inode_security_struct *oldisec = oldinode->i_security;
802 struct inode *newinode = newsb->s_root->d_inode;
803 struct inode_security_struct *newisec = newinode->i_security;
804
805 newisec->sid = oldisec->sid;
806 }
807
808 sb_finish_set_opts(newsb);
809 mutex_unlock(&newsbsec->lock);
810 }
811
812 static int selinux_parse_opts_str(char *options,
813 struct security_mnt_opts *opts)
814 {
815 char *p;
816 char *context = NULL, *defcontext = NULL;
817 char *fscontext = NULL, *rootcontext = NULL;
818 int rc, num_mnt_opts = 0;
819
820 opts->num_mnt_opts = 0;
821
822 /* Standard string-based options. */
823 while ((p = strsep(&options, "|")) != NULL) {
824 int token;
825 substring_t args[MAX_OPT_ARGS];
826
827 if (!*p)
828 continue;
829
830 token = match_token(p, tokens, args);
831
832 switch (token) {
833 case Opt_context:
834 if (context || defcontext) {
835 rc = -EINVAL;
836 printk(KERN_WARNING SEL_MOUNT_FAIL_MSG);
837 goto out_err;
838 }
839 context = match_strdup(&args[0]);
840 if (!context) {
841 rc = -ENOMEM;
842 goto out_err;
843 }
844 break;
845
846 case Opt_fscontext:
847 if (fscontext) {
848 rc = -EINVAL;
849 printk(KERN_WARNING SEL_MOUNT_FAIL_MSG);
850 goto out_err;
851 }
852 fscontext = match_strdup(&args[0]);
853 if (!fscontext) {
854 rc = -ENOMEM;
855 goto out_err;
856 }
857 break;
858
859 case Opt_rootcontext:
860 if (rootcontext) {
861 rc = -EINVAL;
862 printk(KERN_WARNING SEL_MOUNT_FAIL_MSG);
863 goto out_err;
864 }
865 rootcontext = match_strdup(&args[0]);
866 if (!rootcontext) {
867 rc = -ENOMEM;
868 goto out_err;
869 }
870 break;
871
872 case Opt_defcontext:
873 if (context || defcontext) {
874 rc = -EINVAL;
875 printk(KERN_WARNING SEL_MOUNT_FAIL_MSG);
876 goto out_err;
877 }
878 defcontext = match_strdup(&args[0]);
879 if (!defcontext) {
880 rc = -ENOMEM;
881 goto out_err;
882 }
883 break;
884 case Opt_labelsupport:
885 break;
886 default:
887 rc = -EINVAL;
888 printk(KERN_WARNING "SELinux: unknown mount option\n");
889 goto out_err;
890
891 }
892 }
893
894 rc = -ENOMEM;
895 opts->mnt_opts = kcalloc(NUM_SEL_MNT_OPTS, sizeof(char *), GFP_ATOMIC);
896 if (!opts->mnt_opts)
897 goto out_err;
898
899 opts->mnt_opts_flags = kcalloc(NUM_SEL_MNT_OPTS, sizeof(int), GFP_ATOMIC);
900 if (!opts->mnt_opts_flags) {
901 kfree(opts->mnt_opts);
902 goto out_err;
903 }
904
905 if (fscontext) {
906 opts->mnt_opts[num_mnt_opts] = fscontext;
907 opts->mnt_opts_flags[num_mnt_opts++] = FSCONTEXT_MNT;
908 }
909 if (context) {
910 opts->mnt_opts[num_mnt_opts] = context;
911 opts->mnt_opts_flags[num_mnt_opts++] = CONTEXT_MNT;
912 }
913 if (rootcontext) {
914 opts->mnt_opts[num_mnt_opts] = rootcontext;
915 opts->mnt_opts_flags[num_mnt_opts++] = ROOTCONTEXT_MNT;
916 }
917 if (defcontext) {
918 opts->mnt_opts[num_mnt_opts] = defcontext;
919 opts->mnt_opts_flags[num_mnt_opts++] = DEFCONTEXT_MNT;
920 }
921
922 opts->num_mnt_opts = num_mnt_opts;
923 return 0;
924
925 out_err:
926 kfree(context);
927 kfree(defcontext);
928 kfree(fscontext);
929 kfree(rootcontext);
930 return rc;
931 }
932 /*
933 * string mount options parsing and call set the sbsec
934 */
935 static int superblock_doinit(struct super_block *sb, void *data)
936 {
937 int rc = 0;
938 char *options = data;
939 struct security_mnt_opts opts;
940
941 security_init_mnt_opts(&opts);
942
943 if (!data)
944 goto out;
945
946 BUG_ON(sb->s_type->fs_flags & FS_BINARY_MOUNTDATA);
947
948 rc = selinux_parse_opts_str(options, &opts);
949 if (rc)
950 goto out_err;
951
952 out:
953 rc = selinux_set_mnt_opts(sb, &opts);
954
955 out_err:
956 security_free_mnt_opts(&opts);
957 return rc;
958 }
959
960 static void selinux_write_opts(struct seq_file *m,
961 struct security_mnt_opts *opts)
962 {
963 int i;
964 char *prefix;
965
966 for (i = 0; i < opts->num_mnt_opts; i++) {
967 char *has_comma;
968
969 if (opts->mnt_opts[i])
970 has_comma = strchr(opts->mnt_opts[i], ',');
971 else
972 has_comma = NULL;
973
974 switch (opts->mnt_opts_flags[i]) {
975 case CONTEXT_MNT:
976 prefix = CONTEXT_STR;
977 break;
978 case FSCONTEXT_MNT:
979 prefix = FSCONTEXT_STR;
980 break;
981 case ROOTCONTEXT_MNT:
982 prefix = ROOTCONTEXT_STR;
983 break;
984 case DEFCONTEXT_MNT:
985 prefix = DEFCONTEXT_STR;
986 break;
987 case SE_SBLABELSUPP:
988 seq_putc(m, ',');
989 seq_puts(m, LABELSUPP_STR);
990 continue;
991 default:
992 BUG();
993 return;
994 };
995 /* we need a comma before each option */
996 seq_putc(m, ',');
997 seq_puts(m, prefix);
998 if (has_comma)
999 seq_putc(m, '\"');
1000 seq_puts(m, opts->mnt_opts[i]);
1001 if (has_comma)
1002 seq_putc(m, '\"');
1003 }
1004 }
1005
1006 static int selinux_sb_show_options(struct seq_file *m, struct super_block *sb)
1007 {
1008 struct security_mnt_opts opts;
1009 int rc;
1010
1011 rc = selinux_get_mnt_opts(sb, &opts);
1012 if (rc) {
1013 /* before policy load we may get EINVAL, don't show anything */
1014 if (rc == -EINVAL)
1015 rc = 0;
1016 return rc;
1017 }
1018
1019 selinux_write_opts(m, &opts);
1020
1021 security_free_mnt_opts(&opts);
1022
1023 return rc;
1024 }
1025
1026 static inline u16 inode_mode_to_security_class(umode_t mode)
1027 {
1028 switch (mode & S_IFMT) {
1029 case S_IFSOCK:
1030 return SECCLASS_SOCK_FILE;
1031 case S_IFLNK:
1032 return SECCLASS_LNK_FILE;
1033 case S_IFREG:
1034 return SECCLASS_FILE;
1035 case S_IFBLK:
1036 return SECCLASS_BLK_FILE;
1037 case S_IFDIR:
1038 return SECCLASS_DIR;
1039 case S_IFCHR:
1040 return SECCLASS_CHR_FILE;
1041 case S_IFIFO:
1042 return SECCLASS_FIFO_FILE;
1043
1044 }
1045
1046 return SECCLASS_FILE;
1047 }
1048
1049 static inline int default_protocol_stream(int protocol)
1050 {
1051 return (protocol == IPPROTO_IP || protocol == IPPROTO_TCP);
1052 }
1053
1054 static inline int default_protocol_dgram(int protocol)
1055 {
1056 return (protocol == IPPROTO_IP || protocol == IPPROTO_UDP);
1057 }
1058
1059 static inline u16 socket_type_to_security_class(int family, int type, int protocol)
1060 {
1061 switch (family) {
1062 case PF_UNIX:
1063 switch (type) {
1064 case SOCK_STREAM:
1065 case SOCK_SEQPACKET:
1066 return SECCLASS_UNIX_STREAM_SOCKET;
1067 case SOCK_DGRAM:
1068 return SECCLASS_UNIX_DGRAM_SOCKET;
1069 }
1070 break;
1071 case PF_INET:
1072 case PF_INET6:
1073 switch (type) {
1074 case SOCK_STREAM:
1075 if (default_protocol_stream(protocol))
1076 return SECCLASS_TCP_SOCKET;
1077 else
1078 return SECCLASS_RAWIP_SOCKET;
1079 case SOCK_DGRAM:
1080 if (default_protocol_dgram(protocol))
1081 return SECCLASS_UDP_SOCKET;
1082 else
1083 return SECCLASS_RAWIP_SOCKET;
1084 case SOCK_DCCP:
1085 return SECCLASS_DCCP_SOCKET;
1086 default:
1087 return SECCLASS_RAWIP_SOCKET;
1088 }
1089 break;
1090 case PF_NETLINK:
1091 switch (protocol) {
1092 case NETLINK_ROUTE:
1093 return SECCLASS_NETLINK_ROUTE_SOCKET;
1094 case NETLINK_FIREWALL:
1095 return SECCLASS_NETLINK_FIREWALL_SOCKET;
1096 case NETLINK_INET_DIAG:
1097 return SECCLASS_NETLINK_TCPDIAG_SOCKET;
1098 case NETLINK_NFLOG:
1099 return SECCLASS_NETLINK_NFLOG_SOCKET;
1100 case NETLINK_XFRM:
1101 return SECCLASS_NETLINK_XFRM_SOCKET;
1102 case NETLINK_SELINUX:
1103 return SECCLASS_NETLINK_SELINUX_SOCKET;
1104 case NETLINK_AUDIT:
1105 return SECCLASS_NETLINK_AUDIT_SOCKET;
1106 case NETLINK_IP6_FW:
1107 return SECCLASS_NETLINK_IP6FW_SOCKET;
1108 case NETLINK_DNRTMSG:
1109 return SECCLASS_NETLINK_DNRT_SOCKET;
1110 case NETLINK_KOBJECT_UEVENT:
1111 return SECCLASS_NETLINK_KOBJECT_UEVENT_SOCKET;
1112 default:
1113 return SECCLASS_NETLINK_SOCKET;
1114 }
1115 case PF_PACKET:
1116 return SECCLASS_PACKET_SOCKET;
1117 case PF_KEY:
1118 return SECCLASS_KEY_SOCKET;
1119 case PF_APPLETALK:
1120 return SECCLASS_APPLETALK_SOCKET;
1121 }
1122
1123 return SECCLASS_SOCKET;
1124 }
1125
1126 #ifdef CONFIG_PROC_FS
1127 static int selinux_proc_get_sid(struct dentry *dentry,
1128 u16 tclass,
1129 u32 *sid)
1130 {
1131 int rc;
1132 char *buffer, *path;
1133
1134 buffer = (char *)__get_free_page(GFP_KERNEL);
1135 if (!buffer)
1136 return -ENOMEM;
1137
1138 path = dentry_path_raw(dentry, buffer, PAGE_SIZE);
1139 if (IS_ERR(path))
1140 rc = PTR_ERR(path);
1141 else {
1142 /* each process gets a /proc/PID/ entry. Strip off the
1143 * PID part to get a valid selinux labeling.
1144 * e.g. /proc/1/net/rpc/nfs -> /net/rpc/nfs */
1145 while (path[1] >= '0' && path[1] <= '9') {
1146 path[1] = '/';
1147 path++;
1148 }
1149 rc = security_genfs_sid("proc", path, tclass, sid);
1150 }
1151 free_page((unsigned long)buffer);
1152 return rc;
1153 }
1154 #else
1155 static int selinux_proc_get_sid(struct dentry *dentry,
1156 u16 tclass,
1157 u32 *sid)
1158 {
1159 return -EINVAL;
1160 }
1161 #endif
1162
1163 /* The inode's security attributes must be initialized before first use. */
1164 static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dentry)
1165 {
1166 struct superblock_security_struct *sbsec = NULL;
1167 struct inode_security_struct *isec = inode->i_security;
1168 u32 sid;
1169 struct dentry *dentry;
1170 #define INITCONTEXTLEN 255
1171 char *context = NULL;
1172 unsigned len = 0;
1173 int rc = 0;
1174
1175 if (isec->initialized)
1176 goto out;
1177
1178 mutex_lock(&isec->lock);
1179 if (isec->initialized)
1180 goto out_unlock;
1181
1182 sbsec = inode->i_sb->s_security;
1183 if (!(sbsec->flags & SE_SBINITIALIZED)) {
1184 /* Defer initialization until selinux_complete_init,
1185 after the initial policy is loaded and the security
1186 server is ready to handle calls. */
1187 spin_lock(&sbsec->isec_lock);
1188 if (list_empty(&isec->list))
1189 list_add(&isec->list, &sbsec->isec_head);
1190 spin_unlock(&sbsec->isec_lock);
1191 goto out_unlock;
1192 }
1193
1194 switch (sbsec->behavior) {
1195 case SECURITY_FS_USE_XATTR:
1196 if (!inode->i_op->getxattr) {
1197 isec->sid = sbsec->def_sid;
1198 break;
1199 }
1200
1201 /* Need a dentry, since the xattr API requires one.
1202 Life would be simpler if we could just pass the inode. */
1203 if (opt_dentry) {
1204 /* Called from d_instantiate or d_splice_alias. */
1205 dentry = dget(opt_dentry);
1206 } else {
1207 /* Called from selinux_complete_init, try to find a dentry. */
1208 dentry = d_find_alias(inode);
1209 }
1210 if (!dentry) {
1211 /*
1212 * this is can be hit on boot when a file is accessed
1213 * before the policy is loaded. When we load policy we
1214 * may find inodes that have no dentry on the
1215 * sbsec->isec_head list. No reason to complain as these
1216 * will get fixed up the next time we go through
1217 * inode_doinit with a dentry, before these inodes could
1218 * be used again by userspace.
1219 */
1220 goto out_unlock;
1221 }
1222
1223 len = INITCONTEXTLEN;
1224 context = kmalloc(len+1, GFP_NOFS);
1225 if (!context) {
1226 rc = -ENOMEM;
1227 dput(dentry);
1228 goto out_unlock;
1229 }
1230 context[len] = '\0';
1231 rc = inode->i_op->getxattr(dentry, XATTR_NAME_SELINUX,
1232 context, len);
1233 if (rc == -ERANGE) {
1234 kfree(context);
1235
1236 /* Need a larger buffer. Query for the right size. */
1237 rc = inode->i_op->getxattr(dentry, XATTR_NAME_SELINUX,
1238 NULL, 0);
1239 if (rc < 0) {
1240 dput(dentry);
1241 goto out_unlock;
1242 }
1243 len = rc;
1244 context = kmalloc(len+1, GFP_NOFS);
1245 if (!context) {
1246 rc = -ENOMEM;
1247 dput(dentry);
1248 goto out_unlock;
1249 }
1250 context[len] = '\0';
1251 rc = inode->i_op->getxattr(dentry,
1252 XATTR_NAME_SELINUX,
1253 context, len);
1254 }
1255 dput(dentry);
1256 if (rc < 0) {
1257 if (rc != -ENODATA) {
1258 printk(KERN_WARNING "SELinux: %s: getxattr returned "
1259 "%d for dev=%s ino=%ld\n", __func__,
1260 -rc, inode->i_sb->s_id, inode->i_ino);
1261 kfree(context);
1262 goto out_unlock;
1263 }
1264 /* Map ENODATA to the default file SID */
1265 sid = sbsec->def_sid;
1266 rc = 0;
1267 } else {
1268 rc = security_context_to_sid_default(context, rc, &sid,
1269 sbsec->def_sid,
1270 GFP_NOFS);
1271 if (rc) {
1272 char *dev = inode->i_sb->s_id;
1273 unsigned long ino = inode->i_ino;
1274
1275 if (rc == -EINVAL) {
1276 if (printk_ratelimit())
1277 printk(KERN_NOTICE "SELinux: inode=%lu on dev=%s was found to have an invalid "
1278 "context=%s. This indicates you may need to relabel the inode or the "
1279 "filesystem in question.\n", ino, dev, context);
1280 } else {
1281 printk(KERN_WARNING "SELinux: %s: context_to_sid(%s) "
1282 "returned %d for dev=%s ino=%ld\n",
1283 __func__, context, -rc, dev, ino);
1284 }
1285 kfree(context);
1286 /* Leave with the unlabeled SID */
1287 rc = 0;
1288 break;
1289 }
1290 }
1291 kfree(context);
1292 isec->sid = sid;
1293 break;
1294 case SECURITY_FS_USE_TASK:
1295 isec->sid = isec->task_sid;
1296 break;
1297 case SECURITY_FS_USE_TRANS:
1298 /* Default to the fs SID. */
1299 isec->sid = sbsec->sid;
1300
1301 /* Try to obtain a transition SID. */
1302 isec->sclass = inode_mode_to_security_class(inode->i_mode);
1303 rc = security_transition_sid(isec->task_sid, sbsec->sid,
1304 isec->sclass, NULL, &sid);
1305 if (rc)
1306 goto out_unlock;
1307 isec->sid = sid;
1308 break;
1309 case SECURITY_FS_USE_MNTPOINT:
1310 isec->sid = sbsec->mntpoint_sid;
1311 break;
1312 default:
1313 /* Default to the fs superblock SID. */
1314 isec->sid = sbsec->sid;
1315
1316 if ((sbsec->flags & SE_SBPROC) && !S_ISLNK(inode->i_mode)) {
1317 if (opt_dentry) {
1318 isec->sclass = inode_mode_to_security_class(inode->i_mode);
1319 rc = selinux_proc_get_sid(opt_dentry,
1320 isec->sclass,
1321 &sid);
1322 if (rc)
1323 goto out_unlock;
1324 isec->sid = sid;
1325 }
1326 }
1327 break;
1328 }
1329
1330 isec->initialized = 1;
1331
1332 out_unlock:
1333 mutex_unlock(&isec->lock);
1334 out:
1335 if (isec->sclass == SECCLASS_FILE)
1336 isec->sclass = inode_mode_to_security_class(inode->i_mode);
1337 return rc;
1338 }
1339
1340 /* Convert a Linux signal to an access vector. */
1341 static inline u32 signal_to_av(int sig)
1342 {
1343 u32 perm = 0;
1344
1345 switch (sig) {
1346 case SIGCHLD:
1347 /* Commonly granted from child to parent. */
1348 perm = PROCESS__SIGCHLD;
1349 break;
1350 case SIGKILL:
1351 /* Cannot be caught or ignored */
1352 perm = PROCESS__SIGKILL;
1353 break;
1354 case SIGSTOP:
1355 /* Cannot be caught or ignored */
1356 perm = PROCESS__SIGSTOP;
1357 break;
1358 default:
1359 /* All other signals. */
1360 perm = PROCESS__SIGNAL;
1361 break;
1362 }
1363
1364 return perm;
1365 }
1366
1367 /*
1368 * Check permission between a pair of credentials
1369 * fork check, ptrace check, etc.
1370 */
1371 static int cred_has_perm(const struct cred *actor,
1372 const struct cred *target,
1373 u32 perms)
1374 {
1375 u32 asid = cred_sid(actor), tsid = cred_sid(target);
1376
1377 return avc_has_perm(asid, tsid, SECCLASS_PROCESS, perms, NULL);
1378 }
1379
1380 /*
1381 * Check permission between a pair of tasks, e.g. signal checks,
1382 * fork check, ptrace check, etc.
1383 * tsk1 is the actor and tsk2 is the target
1384 * - this uses the default subjective creds of tsk1
1385 */
1386 static int task_has_perm(const struct task_struct *tsk1,
1387 const struct task_struct *tsk2,
1388 u32 perms)
1389 {
1390 const struct task_security_struct *__tsec1, *__tsec2;
1391 u32 sid1, sid2;
1392
1393 rcu_read_lock();
1394 __tsec1 = __task_cred(tsk1)->security; sid1 = __tsec1->sid;
1395 __tsec2 = __task_cred(tsk2)->security; sid2 = __tsec2->sid;
1396 rcu_read_unlock();
1397 return avc_has_perm(sid1, sid2, SECCLASS_PROCESS, perms, NULL);
1398 }
1399
1400 /*
1401 * Check permission between current and another task, e.g. signal checks,
1402 * fork check, ptrace check, etc.
1403 * current is the actor and tsk2 is the target
1404 * - this uses current's subjective creds
1405 */
1406 static int current_has_perm(const struct task_struct *tsk,
1407 u32 perms)
1408 {
1409 u32 sid, tsid;
1410
1411 sid = current_sid();
1412 tsid = task_sid(tsk);
1413 return avc_has_perm(sid, tsid, SECCLASS_PROCESS, perms, NULL);
1414 }
1415
1416 #if CAP_LAST_CAP > 63
1417 #error Fix SELinux to handle capabilities > 63.
1418 #endif
1419
1420 /* Check whether a task is allowed to use a capability. */
1421 static int task_has_capability(struct task_struct *tsk,
1422 const struct cred *cred,
1423 int cap, int audit)
1424 {
1425 struct common_audit_data ad;
1426 struct av_decision avd;
1427 u16 sclass;
1428 u32 sid = cred_sid(cred);
1429 u32 av = CAP_TO_MASK(cap);
1430 int rc;
1431
1432 COMMON_AUDIT_DATA_INIT(&ad, CAP);
1433 ad.tsk = tsk;
1434 ad.u.cap = cap;
1435
1436 switch (CAP_TO_INDEX(cap)) {
1437 case 0:
1438 sclass = SECCLASS_CAPABILITY;
1439 break;
1440 case 1:
1441 sclass = SECCLASS_CAPABILITY2;
1442 break;
1443 default:
1444 printk(KERN_ERR
1445 "SELinux: out of range capability %d\n", cap);
1446 BUG();
1447 return -EINVAL;
1448 }
1449
1450 rc = avc_has_perm_noaudit(sid, sid, sclass, av, 0, &avd);
1451 if (audit == SECURITY_CAP_AUDIT) {
1452 int rc2 = avc_audit(sid, sid, sclass, av, &avd, rc, &ad, 0);
1453 if (rc2)
1454 return rc2;
1455 }
1456 return rc;
1457 }
1458
1459 /* Check whether a task is allowed to use a system operation. */
1460 static int task_has_system(struct task_struct *tsk,
1461 u32 perms)
1462 {
1463 u32 sid = task_sid(tsk);
1464
1465 return avc_has_perm(sid, SECINITSID_KERNEL,
1466 SECCLASS_SYSTEM, perms, NULL);
1467 }
1468
1469 /* Check whether a task has a particular permission to an inode.
1470 The 'adp' parameter is optional and allows other audit
1471 data to be passed (e.g. the dentry). */
1472 static int inode_has_perm(const struct cred *cred,
1473 struct inode *inode,
1474 u32 perms,
1475 struct common_audit_data *adp,
1476 unsigned flags)
1477 {
1478 struct inode_security_struct *isec;
1479 u32 sid;
1480
1481 validate_creds(cred);
1482
1483 if (unlikely(IS_PRIVATE(inode)))
1484 return 0;
1485
1486 sid = cred_sid(cred);
1487 isec = inode->i_security;
1488
1489 return avc_has_perm_flags(sid, isec->sid, isec->sclass, perms, adp, flags);
1490 }
1491
1492 static int inode_has_perm_noadp(const struct cred *cred,
1493 struct inode *inode,
1494 u32 perms,
1495 unsigned flags)
1496 {
1497 struct common_audit_data ad;
1498
1499 COMMON_AUDIT_DATA_INIT(&ad, INODE);
1500 ad.u.inode = inode;
1501 return inode_has_perm(cred, inode, perms, &ad, flags);
1502 }
1503
1504 /* Same as inode_has_perm, but pass explicit audit data containing
1505 the dentry to help the auditing code to more easily generate the
1506 pathname if needed. */
1507 static inline int dentry_has_perm(const struct cred *cred,
1508 struct dentry *dentry,
1509 u32 av)
1510 {
1511 struct inode *inode = dentry->d_inode;
1512 struct common_audit_data ad;
1513
1514 COMMON_AUDIT_DATA_INIT(&ad, DENTRY);
1515 ad.u.dentry = dentry;
1516 return inode_has_perm(cred, inode, av, &ad, 0);
1517 }
1518
1519 /* Same as inode_has_perm, but pass explicit audit data containing
1520 the path to help the auditing code to more easily generate the
1521 pathname if needed. */
1522 static inline int path_has_perm(const struct cred *cred,
1523 struct path *path,
1524 u32 av)
1525 {
1526 struct inode *inode = path->dentry->d_inode;
1527 struct common_audit_data ad;
1528
1529 COMMON_AUDIT_DATA_INIT(&ad, PATH);
1530 ad.u.path = *path;
1531 return inode_has_perm(cred, inode, av, &ad, 0);
1532 }
1533
1534 /* Check whether a task can use an open file descriptor to
1535 access an inode in a given way. Check access to the
1536 descriptor itself, and then use dentry_has_perm to
1537 check a particular permission to the file.
1538 Access to the descriptor is implicitly granted if it
1539 has the same SID as the process. If av is zero, then
1540 access to the file is not checked, e.g. for cases
1541 where only the descriptor is affected like seek. */
1542 static int file_has_perm(const struct cred *cred,
1543 struct file *file,
1544 u32 av)
1545 {
1546 struct file_security_struct *fsec = file->f_security;
1547 struct inode *inode = file->f_path.dentry->d_inode;
1548 struct common_audit_data ad;
1549 u32 sid = cred_sid(cred);
1550 int rc;
1551
1552 COMMON_AUDIT_DATA_INIT(&ad, PATH);
1553 ad.u.path = file->f_path;
1554
1555 if (sid != fsec->sid) {
1556 rc = avc_has_perm(sid, fsec->sid,
1557 SECCLASS_FD,
1558 FD__USE,
1559 &ad);
1560 if (rc)
1561 goto out;
1562 }
1563
1564 /* av is zero if only checking access to the descriptor. */
1565 rc = 0;
1566 if (av)
1567 rc = inode_has_perm(cred, inode, av, &ad, 0);
1568
1569 out:
1570 return rc;
1571 }
1572
1573 /* Check whether a task can create a file. */
1574 static int may_create(struct inode *dir,
1575 struct dentry *dentry,
1576 u16 tclass)
1577 {
1578 const struct task_security_struct *tsec = current_security();
1579 struct inode_security_struct *dsec;
1580 struct superblock_security_struct *sbsec;
1581 u32 sid, newsid;
1582 struct common_audit_data ad;
1583 int rc;
1584
1585 dsec = dir->i_security;
1586 sbsec = dir->i_sb->s_security;
1587
1588 sid = tsec->sid;
1589 newsid = tsec->create_sid;
1590
1591 COMMON_AUDIT_DATA_INIT(&ad, DENTRY);
1592 ad.u.dentry = dentry;
1593
1594 rc = avc_has_perm(sid, dsec->sid, SECCLASS_DIR,
1595 DIR__ADD_NAME | DIR__SEARCH,
1596 &ad);
1597 if (rc)
1598 return rc;
1599
1600 if (!newsid || !(sbsec->flags & SE_SBLABELSUPP)) {
1601 rc = security_transition_sid(sid, dsec->sid, tclass,
1602 &dentry->d_name, &newsid);
1603 if (rc)
1604 return rc;
1605 }
1606
1607 rc = avc_has_perm(sid, newsid, tclass, FILE__CREATE, &ad);
1608 if (rc)
1609 return rc;
1610
1611 return avc_has_perm(newsid, sbsec->sid,
1612 SECCLASS_FILESYSTEM,
1613 FILESYSTEM__ASSOCIATE, &ad);
1614 }
1615
1616 /* Check whether a task can create a key. */
1617 static int may_create_key(u32 ksid,
1618 struct task_struct *ctx)
1619 {
1620 u32 sid = task_sid(ctx);
1621
1622 return avc_has_perm(sid, ksid, SECCLASS_KEY, KEY__CREATE, NULL);
1623 }
1624
1625 #define MAY_LINK 0
1626 #define MAY_UNLINK 1
1627 #define MAY_RMDIR 2
1628
1629 /* Check whether a task can link, unlink, or rmdir a file/directory. */
1630 static int may_link(struct inode *dir,
1631 struct dentry *dentry,
1632 int kind)
1633
1634 {
1635 struct inode_security_struct *dsec, *isec;
1636 struct common_audit_data ad;
1637 u32 sid = current_sid();
1638 u32 av;
1639 int rc;
1640
1641 dsec = dir->i_security;
1642 isec = dentry->d_inode->i_security;
1643
1644 COMMON_AUDIT_DATA_INIT(&ad, DENTRY);
1645 ad.u.dentry = dentry;
1646
1647 av = DIR__SEARCH;
1648 av |= (kind ? DIR__REMOVE_NAME : DIR__ADD_NAME);
1649 rc = avc_has_perm(sid, dsec->sid, SECCLASS_DIR, av, &ad);
1650 if (rc)
1651 return rc;
1652
1653 switch (kind) {
1654 case MAY_LINK:
1655 av = FILE__LINK;
1656 break;
1657 case MAY_UNLINK:
1658 av = FILE__UNLINK;
1659 break;
1660 case MAY_RMDIR:
1661 av = DIR__RMDIR;
1662 break;
1663 default:
1664 printk(KERN_WARNING "SELinux: %s: unrecognized kind %d\n",
1665 __func__, kind);
1666 return 0;
1667 }
1668
1669 rc = avc_has_perm(sid, isec->sid, isec->sclass, av, &ad);
1670 return rc;
1671 }
1672
1673 static inline int may_rename(struct inode *old_dir,
1674 struct dentry *old_dentry,
1675 struct inode *new_dir,
1676 struct dentry *new_dentry)
1677 {
1678 struct inode_security_struct *old_dsec, *new_dsec, *old_isec, *new_isec;
1679 struct common_audit_data ad;
1680 u32 sid = current_sid();
1681 u32 av;
1682 int old_is_dir, new_is_dir;
1683 int rc;
1684
1685 old_dsec = old_dir->i_security;
1686 old_isec = old_dentry->d_inode->i_security;
1687 old_is_dir = S_ISDIR(old_dentry->d_inode->i_mode);
1688 new_dsec = new_dir->i_security;
1689
1690 COMMON_AUDIT_DATA_INIT(&ad, DENTRY);
1691
1692 ad.u.dentry = old_dentry;
1693 rc = avc_has_perm(sid, old_dsec->sid, SECCLASS_DIR,
1694 DIR__REMOVE_NAME | DIR__SEARCH, &ad);
1695 if (rc)
1696 return rc;
1697 rc = avc_has_perm(sid, old_isec->sid,
1698 old_isec->sclass, FILE__RENAME, &ad);
1699 if (rc)
1700 return rc;
1701 if (old_is_dir && new_dir != old_dir) {
1702 rc = avc_has_perm(sid, old_isec->sid,
1703 old_isec->sclass, DIR__REPARENT, &ad);
1704 if (rc)
1705 return rc;
1706 }
1707
1708 ad.u.dentry = new_dentry;
1709 av = DIR__ADD_NAME | DIR__SEARCH;
1710 if (new_dentry->d_inode)
1711 av |= DIR__REMOVE_NAME;
1712 rc = avc_has_perm(sid, new_dsec->sid, SECCLASS_DIR, av, &ad);
1713 if (rc)
1714 return rc;
1715 if (new_dentry->d_inode) {
1716 new_isec = new_dentry->d_inode->i_security;
1717 new_is_dir = S_ISDIR(new_dentry->d_inode->i_mode);
1718 rc = avc_has_perm(sid, new_isec->sid,
1719 new_isec->sclass,
1720 (new_is_dir ? DIR__RMDIR : FILE__UNLINK), &ad);
1721 if (rc)
1722 return rc;
1723 }
1724
1725 return 0;
1726 }
1727
1728 /* Check whether a task can perform a filesystem operation. */
1729 static int superblock_has_perm(const struct cred *cred,
1730 struct super_block *sb,
1731 u32 perms,
1732 struct common_audit_data *ad)
1733 {
1734 struct superblock_security_struct *sbsec;
1735 u32 sid = cred_sid(cred);
1736
1737 sbsec = sb->s_security;
1738 return avc_has_perm(sid, sbsec->sid, SECCLASS_FILESYSTEM, perms, ad);
1739 }
1740
1741 /* Convert a Linux mode and permission mask to an access vector. */
1742 static inline u32 file_mask_to_av(int mode, int mask)
1743 {
1744 u32 av = 0;
1745
1746 if ((mode & S_IFMT) != S_IFDIR) {
1747 if (mask & MAY_EXEC)
1748 av |= FILE__EXECUTE;
1749 if (mask & MAY_READ)
1750 av |= FILE__READ;
1751
1752 if (mask & MAY_APPEND)
1753 av |= FILE__APPEND;
1754 else if (mask & MAY_WRITE)
1755 av |= FILE__WRITE;
1756
1757 } else {
1758 if (mask & MAY_EXEC)
1759 av |= DIR__SEARCH;
1760 if (mask & MAY_WRITE)
1761 av |= DIR__WRITE;
1762 if (mask & MAY_READ)
1763 av |= DIR__READ;
1764 }
1765
1766 return av;
1767 }
1768
1769 /* Convert a Linux file to an access vector. */
1770 static inline u32 file_to_av(struct file *file)
1771 {
1772 u32 av = 0;
1773
1774 if (file->f_mode & FMODE_READ)
1775 av |= FILE__READ;
1776 if (file->f_mode & FMODE_WRITE) {
1777 if (file->f_flags & O_APPEND)
1778 av |= FILE__APPEND;
1779 else
1780 av |= FILE__WRITE;
1781 }
1782 if (!av) {
1783 /*
1784 * Special file opened with flags 3 for ioctl-only use.
1785 */
1786 av = FILE__IOCTL;
1787 }
1788
1789 return av;
1790 }
1791
1792 /*
1793 * Convert a file to an access vector and include the correct open
1794 * open permission.
1795 */
1796 static inline u32 open_file_to_av(struct file *file)
1797 {
1798 u32 av = file_to_av(file);
1799
1800 if (selinux_policycap_openperm)
1801 av |= FILE__OPEN;
1802
1803 return av;
1804 }
1805
1806 /* Hook functions begin here. */
1807
1808 static int selinux_ptrace_access_check(struct task_struct *child,
1809 unsigned int mode)
1810 {
1811 int rc;
1812
1813 rc = cap_ptrace_access_check(child, mode);
1814 if (rc)
1815 return rc;
1816
1817 if (mode == PTRACE_MODE_READ) {
1818 u32 sid = current_sid();
1819 u32 csid = task_sid(child);
1820 return avc_has_perm(sid, csid, SECCLASS_FILE, FILE__READ, NULL);
1821 }
1822
1823 return current_has_perm(child, PROCESS__PTRACE);
1824 }
1825
1826 static int selinux_ptrace_traceme(struct task_struct *parent)
1827 {
1828 int rc;
1829
1830 rc = cap_ptrace_traceme(parent);
1831 if (rc)
1832 return rc;
1833
1834 return task_has_perm(parent, current, PROCESS__PTRACE);
1835 }
1836
1837 static int selinux_capget(struct task_struct *target, kernel_cap_t *effective,
1838 kernel_cap_t *inheritable, kernel_cap_t *permitted)
1839 {
1840 int error;
1841
1842 error = current_has_perm(target, PROCESS__GETCAP);
1843 if (error)
1844 return error;
1845
1846 return cap_capget(target, effective, inheritable, permitted);
1847 }
1848
1849 static int selinux_capset(struct cred *new, const struct cred *old,
1850 const kernel_cap_t *effective,
1851 const kernel_cap_t *inheritable,
1852 const kernel_cap_t *permitted)
1853 {
1854 int error;
1855
1856 error = cap_capset(new, old,
1857 effective, inheritable, permitted);
1858 if (error)
1859 return error;
1860
1861 return cred_has_perm(old, new, PROCESS__SETCAP);
1862 }
1863
1864 /*
1865 * (This comment used to live with the selinux_task_setuid hook,
1866 * which was removed).
1867 *
1868 * Since setuid only affects the current process, and since the SELinux
1869 * controls are not based on the Linux identity attributes, SELinux does not
1870 * need to control this operation. However, SELinux does control the use of
1871 * the CAP_SETUID and CAP_SETGID capabilities using the capable hook.
1872 */
1873
1874 static int selinux_capable(struct task_struct *tsk, const struct cred *cred,
1875 struct user_namespace *ns, int cap, int audit)
1876 {
1877 int rc;
1878
1879 rc = cap_capable(tsk, cred, ns, cap, audit);
1880 if (rc)
1881 return rc;
1882
1883 return task_has_capability(tsk, cred, cap, audit);
1884 }
1885
1886 static int selinux_quotactl(int cmds, int type, int id, struct super_block *sb)
1887 {
1888 const struct cred *cred = current_cred();
1889 int rc = 0;
1890
1891 if (!sb)
1892 return 0;
1893
1894 switch (cmds) {
1895 case Q_SYNC:
1896 case Q_QUOTAON:
1897 case Q_QUOTAOFF:
1898 case Q_SETINFO:
1899 case Q_SETQUOTA:
1900 rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAMOD, NULL);
1901 break;
1902 case Q_GETFMT:
1903 case Q_GETINFO:
1904 case Q_GETQUOTA:
1905 rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAGET, NULL);
1906 break;
1907 default:
1908 rc = 0; /* let the kernel handle invalid cmds */
1909 break;
1910 }
1911 return rc;
1912 }
1913
1914 static int selinux_quota_on(struct dentry *dentry)
1915 {
1916 const struct cred *cred = current_cred();
1917
1918 return dentry_has_perm(cred, dentry, FILE__QUOTAON);
1919 }
1920
1921 static int selinux_syslog(int type)
1922 {
1923 int rc;
1924
1925 switch (type) {
1926 case SYSLOG_ACTION_READ_ALL: /* Read last kernel messages */
1927 case SYSLOG_ACTION_SIZE_BUFFER: /* Return size of the log buffer */
1928 rc = task_has_system(current, SYSTEM__SYSLOG_READ);
1929 break;
1930 case SYSLOG_ACTION_CONSOLE_OFF: /* Disable logging to console */
1931 case SYSLOG_ACTION_CONSOLE_ON: /* Enable logging to console */
1932 /* Set level of messages printed to console */
1933 case SYSLOG_ACTION_CONSOLE_LEVEL:
1934 rc = task_has_system(current, SYSTEM__SYSLOG_CONSOLE);
1935 break;
1936 case SYSLOG_ACTION_CLOSE: /* Close log */
1937 case SYSLOG_ACTION_OPEN: /* Open log */
1938 case SYSLOG_ACTION_READ: /* Read from log */
1939 case SYSLOG_ACTION_READ_CLEAR: /* Read/clear last kernel messages */
1940 case SYSLOG_ACTION_CLEAR: /* Clear ring buffer */
1941 default:
1942 rc = task_has_system(current, SYSTEM__SYSLOG_MOD);
1943 break;
1944 }
1945 return rc;
1946 }
1947
1948 /*
1949 * Check that a process has enough memory to allocate a new virtual
1950 * mapping. 0 means there is enough memory for the allocation to
1951 * succeed and -ENOMEM implies there is not.
1952 *
1953 * Do not audit the selinux permission check, as this is applied to all
1954 * processes that allocate mappings.
1955 */
1956 static int selinux_vm_enough_memory(struct mm_struct *mm, long pages)
1957 {
1958 int rc, cap_sys_admin = 0;
1959
1960 rc = selinux_capable(current, current_cred(),
1961 &init_user_ns, CAP_SYS_ADMIN,
1962 SECURITY_CAP_NOAUDIT);
1963 if (rc == 0)
1964 cap_sys_admin = 1;
1965
1966 return __vm_enough_memory(mm, pages, cap_sys_admin);
1967 }
1968
1969 /* binprm security operations */
1970
1971 static int selinux_bprm_set_creds(struct linux_binprm *bprm)
1972 {
1973 const struct task_security_struct *old_tsec;
1974 struct task_security_struct *new_tsec;
1975 struct inode_security_struct *isec;
1976 struct common_audit_data ad;
1977 struct inode *inode = bprm->file->f_path.dentry->d_inode;
1978 int rc;
1979
1980 rc = cap_bprm_set_creds(bprm);
1981 if (rc)
1982 return rc;
1983
1984 /* SELinux context only depends on initial program or script and not
1985 * the script interpreter */
1986 if (bprm->cred_prepared)
1987 return 0;
1988
1989 old_tsec = current_security();
1990 new_tsec = bprm->cred->security;
1991 isec = inode->i_security;
1992
1993 /* Default to the current task SID. */
1994 new_tsec->sid = old_tsec->sid;
1995 new_tsec->osid = old_tsec->sid;
1996
1997 /* Reset fs, key, and sock SIDs on execve. */
1998 new_tsec->create_sid = 0;
1999 new_tsec->keycreate_sid = 0;
2000 new_tsec->sockcreate_sid = 0;
2001
2002 if (old_tsec->exec_sid) {
2003 new_tsec->sid = old_tsec->exec_sid;
2004 /* Reset exec SID on execve. */
2005 new_tsec->exec_sid = 0;
2006 } else {
2007 /* Check for a default transition on this program. */
2008 rc = security_transition_sid(old_tsec->sid, isec->sid,
2009 SECCLASS_PROCESS, NULL,
2010 &new_tsec->sid);
2011 if (rc)
2012 return rc;
2013 }
2014
2015 COMMON_AUDIT_DATA_INIT(&ad, PATH);
2016 ad.u.path = bprm->file->f_path;
2017
2018 if (bprm->file->f_path.mnt->mnt_flags & MNT_NOSUID)
2019 new_tsec->sid = old_tsec->sid;
2020
2021 if (new_tsec->sid == old_tsec->sid) {
2022 rc = avc_has_perm(old_tsec->sid, isec->sid,
2023 SECCLASS_FILE, FILE__EXECUTE_NO_TRANS, &ad);
2024 if (rc)
2025 return rc;
2026 } else {
2027 /* Check permissions for the transition. */
2028 rc = avc_has_perm(old_tsec->sid, new_tsec->sid,
2029 SECCLASS_PROCESS, PROCESS__TRANSITION, &ad);
2030 if (rc)
2031 return rc;
2032
2033 rc = avc_has_perm(new_tsec->sid, isec->sid,
2034 SECCLASS_FILE, FILE__ENTRYPOINT, &ad);
2035 if (rc)
2036 return rc;
2037
2038 /* Check for shared state */
2039 if (bprm->unsafe & LSM_UNSAFE_SHARE) {
2040 rc = avc_has_perm(old_tsec->sid, new_tsec->sid,
2041 SECCLASS_PROCESS, PROCESS__SHARE,
2042 NULL);
2043 if (rc)
2044 return -EPERM;
2045 }
2046
2047 /* Make sure that anyone attempting to ptrace over a task that
2048 * changes its SID has the appropriate permit */
2049 if (bprm->unsafe &
2050 (LSM_UNSAFE_PTRACE | LSM_UNSAFE_PTRACE_CAP)) {
2051 struct task_struct *tracer;
2052 struct task_security_struct *sec;
2053 u32 ptsid = 0;
2054
2055 rcu_read_lock();
2056 tracer = ptrace_parent(current);
2057 if (likely(tracer != NULL)) {
2058 sec = __task_cred(tracer)->security;
2059 ptsid = sec->sid;
2060 }
2061 rcu_read_unlock();
2062
2063 if (ptsid != 0) {
2064 rc = avc_has_perm(ptsid, new_tsec->sid,
2065 SECCLASS_PROCESS,
2066 PROCESS__PTRACE, NULL);
2067 if (rc)
2068 return -EPERM;
2069 }
2070 }
2071
2072 /* Clear any possibly unsafe personality bits on exec: */
2073 bprm->per_clear |= PER_CLEAR_ON_SETID;
2074 }
2075
2076 return 0;
2077 }
2078
2079 static int selinux_bprm_secureexec(struct linux_binprm *bprm)
2080 {
2081 const struct task_security_struct *tsec = current_security();
2082 u32 sid, osid;
2083 int atsecure = 0;
2084
2085 sid = tsec->sid;
2086 osid = tsec->osid;
2087
2088 if (osid != sid) {
2089 /* Enable secure mode for SIDs transitions unless
2090 the noatsecure permission is granted between
2091 the two SIDs, i.e. ahp returns 0. */
2092 atsecure = avc_has_perm(osid, sid,
2093 SECCLASS_PROCESS,
2094 PROCESS__NOATSECURE, NULL);
2095 }
2096
2097 return (atsecure || cap_bprm_secureexec(bprm));
2098 }
2099
2100 extern struct vfsmount *selinuxfs_mount;
2101 extern struct dentry *selinux_null;
2102
2103 /* Derived from fs/exec.c:flush_old_files. */
2104 static inline void flush_unauthorized_files(const struct cred *cred,
2105 struct files_struct *files)
2106 {
2107 struct common_audit_data ad;
2108 struct file *file, *devnull = NULL;
2109 struct tty_struct *tty;
2110 struct fdtable *fdt;
2111 long j = -1;
2112 int drop_tty = 0;
2113
2114 tty = get_current_tty();
2115 if (tty) {
2116 spin_lock(&tty_files_lock);
2117 if (!list_empty(&tty->tty_files)) {
2118 struct tty_file_private *file_priv;
2119 struct inode *inode;
2120
2121 /* Revalidate access to controlling tty.
2122 Use inode_has_perm on the tty inode directly rather
2123 than using file_has_perm, as this particular open
2124 file may belong to another process and we are only
2125 interested in the inode-based check here. */
2126 file_priv = list_first_entry(&tty->tty_files,
2127 struct tty_file_private, list);
2128 file = file_priv->file;
2129 inode = file->f_path.dentry->d_inode;
2130 if (inode_has_perm_noadp(cred, inode,
2131 FILE__READ | FILE__WRITE, 0)) {
2132 drop_tty = 1;
2133 }
2134 }
2135 spin_unlock(&tty_files_lock);
2136 tty_kref_put(tty);
2137 }
2138 /* Reset controlling tty. */
2139 if (drop_tty)
2140 no_tty();
2141
2142 /* Revalidate access to inherited open files. */
2143
2144 COMMON_AUDIT_DATA_INIT(&ad, INODE);
2145
2146 spin_lock(&files->file_lock);
2147 for (;;) {
2148 unsigned long set, i;
2149 int fd;
2150
2151 j++;
2152 i = j * __NFDBITS;
2153 fdt = files_fdtable(files);
2154 if (i >= fdt->max_fds)
2155 break;
2156 set = fdt->open_fds->fds_bits[j];
2157 if (!set)
2158 continue;
2159 spin_unlock(&files->file_lock);
2160 for ( ; set ; i++, set >>= 1) {
2161 if (set & 1) {
2162 file = fget(i);
2163 if (!file)
2164 continue;
2165 if (file_has_perm(cred,
2166 file,
2167 file_to_av(file))) {
2168 sys_close(i);
2169 fd = get_unused_fd();
2170 if (fd != i) {
2171 if (fd >= 0)
2172 put_unused_fd(fd);
2173 fput(file);
2174 continue;
2175 }
2176 if (devnull) {
2177 get_file(devnull);
2178 } else {
2179 devnull = dentry_open(
2180 dget(selinux_null),
2181 mntget(selinuxfs_mount),
2182 O_RDWR, cred);
2183 if (IS_ERR(devnull)) {
2184 devnull = NULL;
2185 put_unused_fd(fd);
2186 fput(file);
2187 continue;
2188 }
2189 }
2190 fd_install(fd, devnull);
2191 }
2192 fput(file);
2193 }
2194 }
2195 spin_lock(&files->file_lock);
2196
2197 }
2198 spin_unlock(&files->file_lock);
2199 }
2200
2201 /*
2202 * Prepare a process for imminent new credential changes due to exec
2203 */
2204 static void selinux_bprm_committing_creds(struct linux_binprm *bprm)
2205 {
2206 struct task_security_struct *new_tsec;
2207 struct rlimit *rlim, *initrlim;
2208 int rc, i;
2209
2210 new_tsec = bprm->cred->security;
2211 if (new_tsec->sid == new_tsec->osid)
2212 return;
2213
2214 /* Close files for which the new task SID is not authorized. */
2215 flush_unauthorized_files(bprm->cred, current->files);
2216
2217 /* Always clear parent death signal on SID transitions. */
2218 current->pdeath_signal = 0;
2219
2220 /* Check whether the new SID can inherit resource limits from the old
2221 * SID. If not, reset all soft limits to the lower of the current
2222 * task's hard limit and the init task's soft limit.
2223 *
2224 * Note that the setting of hard limits (even to lower them) can be
2225 * controlled by the setrlimit check. The inclusion of the init task's
2226 * soft limit into the computation is to avoid resetting soft limits
2227 * higher than the default soft limit for cases where the default is
2228 * lower than the hard limit, e.g. RLIMIT_CORE or RLIMIT_STACK.
2229 */
2230 rc = avc_has_perm(new_tsec->osid, new_tsec->sid, SECCLASS_PROCESS,
2231 PROCESS__RLIMITINH, NULL);
2232 if (rc) {
2233 /* protect against do_prlimit() */
2234 task_lock(current);
2235 for (i = 0; i < RLIM_NLIMITS; i++) {
2236 rlim = current->signal->rlim + i;
2237 initrlim = init_task.signal->rlim + i;
2238 rlim->rlim_cur = min(rlim->rlim_max, initrlim->rlim_cur);
2239 }
2240 task_unlock(current);
2241 update_rlimit_cpu(current, rlimit(RLIMIT_CPU));
2242 }
2243 }
2244
2245 /*
2246 * Clean up the process immediately after the installation of new credentials
2247 * due to exec
2248 */
2249 static void selinux_bprm_committed_creds(struct linux_binprm *bprm)
2250 {
2251 const struct task_security_struct *tsec = current_security();
2252 struct itimerval itimer;
2253 u32 osid, sid;
2254 int rc, i;
2255
2256 osid = tsec->osid;
2257 sid = tsec->sid;
2258
2259 if (sid == osid)
2260 return;
2261
2262 /* Check whether the new SID can inherit signal state from the old SID.
2263 * If not, clear itimers to avoid subsequent signal generation and
2264 * flush and unblock signals.
2265 *
2266 * This must occur _after_ the task SID has been updated so that any
2267 * kill done after the flush will be checked against the new SID.
2268 */
2269 rc = avc_has_perm(osid, sid, SECCLASS_PROCESS, PROCESS__SIGINH, NULL);
2270 if (rc) {
2271 memset(&itimer, 0, sizeof itimer);
2272 for (i = 0; i < 3; i++)
2273 do_setitimer(i, &itimer, NULL);
2274 spin_lock_irq(&current->sighand->siglock);
2275 if (!(current->signal->flags & SIGNAL_GROUP_EXIT)) {
2276 __flush_signals(current);
2277 flush_signal_handlers(current, 1);
2278 sigemptyset(&current->blocked);
2279 }
2280 spin_unlock_irq(&current->sighand->siglock);
2281 }
2282
2283 /* Wake up the parent if it is waiting so that it can recheck
2284 * wait permission to the new task SID. */
2285 read_lock(&tasklist_lock);
2286 __wake_up_parent(current, current->real_parent);
2287 read_unlock(&tasklist_lock);
2288 }
2289
2290 /* superblock security operations */
2291
2292 static int selinux_sb_alloc_security(struct super_block *sb)
2293 {
2294 return superblock_alloc_security(sb);
2295 }
2296
2297 static void selinux_sb_free_security(struct super_block *sb)
2298 {
2299 superblock_free_security(sb);
2300 }
2301
2302 static inline int match_prefix(char *prefix, int plen, char *option, int olen)
2303 {
2304 if (plen > olen)
2305 return 0;
2306
2307 return !memcmp(prefix, option, plen);
2308 }
2309
2310 static inline int selinux_option(char *option, int len)
2311 {
2312 return (match_prefix(CONTEXT_STR, sizeof(CONTEXT_STR)-1, option, len) ||
2313 match_prefix(FSCONTEXT_STR, sizeof(FSCONTEXT_STR)-1, option, len) ||
2314 match_prefix(DEFCONTEXT_STR, sizeof(DEFCONTEXT_STR)-1, option, len) ||
2315 match_prefix(ROOTCONTEXT_STR, sizeof(ROOTCONTEXT_STR)-1, option, len) ||
2316 match_prefix(LABELSUPP_STR, sizeof(LABELSUPP_STR)-1, option, len));
2317 }
2318
2319 static inline void take_option(char **to, char *from, int *first, int len)
2320 {
2321 if (!*first) {
2322 **to = ',';
2323 *to += 1;
2324 } else
2325 *first = 0;
2326 memcpy(*to, from, len);
2327 *to += len;
2328 }
2329
2330 static inline void take_selinux_option(char **to, char *from, int *first,
2331 int len)
2332 {
2333 int current_size = 0;
2334
2335 if (!*first) {
2336 **to = '|';
2337 *to += 1;
2338 } else
2339 *first = 0;
2340
2341 while (current_size < len) {
2342 if (*from != '"') {
2343 **to = *from;
2344 *to += 1;
2345 }
2346 from += 1;
2347 current_size += 1;
2348 }
2349 }
2350
2351 static int selinux_sb_copy_data(char *orig, char *copy)
2352 {
2353 int fnosec, fsec, rc = 0;
2354 char *in_save, *in_curr, *in_end;
2355 char *sec_curr, *nosec_save, *nosec;
2356 int open_quote = 0;
2357
2358 in_curr = orig;
2359 sec_curr = copy;
2360
2361 nosec = (char *)get_zeroed_page(GFP_KERNEL);
2362 if (!nosec) {
2363 rc = -ENOMEM;
2364 goto out;
2365 }
2366
2367 nosec_save = nosec;
2368 fnosec = fsec = 1;
2369 in_save = in_end = orig;
2370
2371 do {
2372 if (*in_end == '"')
2373 open_quote = !open_quote;
2374 if ((*in_end == ',' && open_quote == 0) ||
2375 *in_end == '\0') {
2376 int len = in_end - in_curr;
2377
2378 if (selinux_option(in_curr, len))
2379 take_selinux_option(&sec_curr, in_curr, &fsec, len);
2380 else
2381 take_option(&nosec, in_curr, &fnosec, len);
2382
2383 in_curr = in_end + 1;
2384 }
2385 } while (*in_end++);
2386
2387 strcpy(in_save, nosec_save);
2388 free_page((unsigned long)nosec_save);
2389 out:
2390 return rc;
2391 }
2392
2393 static int selinux_sb_remount(struct super_block *sb, void *data)
2394 {
2395 int rc, i, *flags;
2396 struct security_mnt_opts opts;
2397 char *secdata, **mount_options;
2398 struct superblock_security_struct *sbsec = sb->s_security;
2399
2400 if (!(sbsec->flags & SE_SBINITIALIZED))
2401 return 0;
2402
2403 if (!data)
2404 return 0;
2405
2406 if (sb->s_type->fs_flags & FS_BINARY_MOUNTDATA)
2407 return 0;
2408
2409 security_init_mnt_opts(&opts);
2410 secdata = alloc_secdata();
2411 if (!secdata)
2412 return -ENOMEM;
2413 rc = selinux_sb_copy_data(data, secdata);
2414 if (rc)
2415 goto out_free_secdata;
2416
2417 rc = selinux_parse_opts_str(secdata, &opts);
2418 if (rc)
2419 goto out_free_secdata;
2420
2421 mount_options = opts.mnt_opts;
2422 flags = opts.mnt_opts_flags;
2423
2424 for (i = 0; i < opts.num_mnt_opts; i++) {
2425 u32 sid;
2426 size_t len;
2427
2428 if (flags[i] == SE_SBLABELSUPP)
2429 continue;
2430 len = strlen(mount_options[i]);
2431 rc = security_context_to_sid(mount_options[i], len, &sid);
2432 if (rc) {
2433 printk(KERN_WARNING "SELinux: security_context_to_sid"
2434 "(%s) failed for (dev %s, type %s) errno=%d\n",
2435 mount_options[i], sb->s_id, sb->s_type->name, rc);
2436 goto out_free_opts;
2437 }
2438 rc = -EINVAL;
2439 switch (flags[i]) {
2440 case FSCONTEXT_MNT:
2441 if (bad_option(sbsec, FSCONTEXT_MNT, sbsec->sid, sid))
2442 goto out_bad_option;
2443 break;
2444 case CONTEXT_MNT:
2445 if (bad_option(sbsec, CONTEXT_MNT, sbsec->mntpoint_sid, sid))
2446 goto out_bad_option;
2447 break;
2448 case ROOTCONTEXT_MNT: {
2449 struct inode_security_struct *root_isec;
2450 root_isec = sb->s_root->d_inode->i_security;
2451
2452 if (bad_option(sbsec, ROOTCONTEXT_MNT, root_isec->sid, sid))
2453 goto out_bad_option;
2454 break;
2455 }
2456 case DEFCONTEXT_MNT:
2457 if (bad_option(sbsec, DEFCONTEXT_MNT, sbsec->def_sid, sid))
2458 goto out_bad_option;
2459 break;
2460 default:
2461 goto out_free_opts;
2462 }
2463 }
2464
2465 rc = 0;
2466 out_free_opts:
2467 security_free_mnt_opts(&opts);
2468 out_free_secdata:
2469 free_secdata(secdata);
2470 return rc;
2471 out_bad_option:
2472 printk(KERN_WARNING "SELinux: unable to change security options "
2473 "during remount (dev %s, type=%s)\n", sb->s_id,
2474 sb->s_type->name);
2475 goto out_free_opts;
2476 }
2477
2478 static int selinux_sb_kern_mount(struct super_block *sb, int flags, void *data)
2479 {
2480 const struct cred *cred = current_cred();
2481 struct common_audit_data ad;
2482 int rc;
2483
2484 rc = superblock_doinit(sb, data);
2485 if (rc)
2486 return rc;
2487
2488 /* Allow all mounts performed by the kernel */
2489 if (flags & MS_KERNMOUNT)
2490 return 0;
2491
2492 COMMON_AUDIT_DATA_INIT(&ad, DENTRY);
2493 ad.u.dentry = sb->s_root;
2494 return superblock_has_perm(cred, sb, FILESYSTEM__MOUNT, &ad);
2495 }
2496
2497 static int selinux_sb_statfs(struct dentry *dentry)
2498 {
2499 const struct cred *cred = current_cred();
2500 struct common_audit_data ad;
2501
2502 COMMON_AUDIT_DATA_INIT(&ad, DENTRY);
2503 ad.u.dentry = dentry->d_sb->s_root;
2504 return superblock_has_perm(cred, dentry->d_sb, FILESYSTEM__GETATTR, &ad);
2505 }
2506
2507 static int selinux_mount(char *dev_name,
2508 struct path *path,
2509 char *type,
2510 unsigned long flags,
2511 void *data)
2512 {
2513 const struct cred *cred = current_cred();
2514
2515 if (flags & MS_REMOUNT)
2516 return superblock_has_perm(cred, path->mnt->mnt_sb,
2517 FILESYSTEM__REMOUNT, NULL);
2518 else
2519 return path_has_perm(cred, path, FILE__MOUNTON);
2520 }
2521
2522 static int selinux_umount(struct vfsmount *mnt, int flags)
2523 {
2524 const struct cred *cred = current_cred();
2525
2526 return superblock_has_perm(cred, mnt->mnt_sb,
2527 FILESYSTEM__UNMOUNT, NULL);
2528 }
2529
2530 /* inode security operations */
2531
2532 static int selinux_inode_alloc_security(struct inode *inode)
2533 {
2534 return inode_alloc_security(inode);
2535 }
2536
2537 static void selinux_inode_free_security(struct inode *inode)
2538 {
2539 inode_free_security(inode);
2540 }
2541
2542 static int selinux_inode_init_security(struct inode *inode, struct inode *dir,
2543 const struct qstr *qstr, char **name,
2544 void **value, size_t *len)
2545 {
2546 const struct task_security_struct *tsec = current_security();
2547 struct inode_security_struct *dsec;
2548 struct superblock_security_struct *sbsec;
2549 u32 sid, newsid, clen;
2550 int rc;
2551 char *namep = NULL, *context;
2552
2553 dsec = dir->i_security;
2554 sbsec = dir->i_sb->s_security;
2555
2556 sid = tsec->sid;
2557 newsid = tsec->create_sid;
2558
2559 if ((sbsec->flags & SE_SBINITIALIZED) &&
2560 (sbsec->behavior == SECURITY_FS_USE_MNTPOINT))
2561 newsid = sbsec->mntpoint_sid;
2562 else if (!newsid || !(sbsec->flags & SE_SBLABELSUPP)) {
2563 rc = security_transition_sid(sid, dsec->sid,
2564 inode_mode_to_security_class(inode->i_mode),
2565 qstr, &newsid);
2566 if (rc) {
2567 printk(KERN_WARNING "%s: "
2568 "security_transition_sid failed, rc=%d (dev=%s "
2569 "ino=%ld)\n",
2570 __func__,
2571 -rc, inode->i_sb->s_id, inode->i_ino);
2572 return rc;
2573 }
2574 }
2575
2576 /* Possibly defer initialization to selinux_complete_init. */
2577 if (sbsec->flags & SE_SBINITIALIZED) {
2578 struct inode_security_struct *isec = inode->i_security;
2579 isec->sclass = inode_mode_to_security_class(inode->i_mode);
2580 isec->sid = newsid;
2581 isec->initialized = 1;
2582 }
2583
2584 if (!ss_initialized || !(sbsec->flags & SE_SBLABELSUPP))
2585 return -EOPNOTSUPP;
2586
2587 if (name) {
2588 namep = kstrdup(XATTR_SELINUX_SUFFIX, GFP_NOFS);
2589 if (!namep)
2590 return -ENOMEM;
2591 *name = namep;
2592 }
2593
2594 if (value && len) {
2595 rc = security_sid_to_context_force(newsid, &context, &clen);
2596 if (rc) {
2597 kfree(namep);
2598 return rc;
2599 }
2600 *value = context;
2601 *len = clen;
2602 }
2603
2604 return 0;
2605 }
2606
2607 static int selinux_inode_create(struct inode *dir, struct dentry *dentry, int mask)
2608 {
2609 return may_create(dir, dentry, SECCLASS_FILE);
2610 }
2611
2612 static int selinux_inode_link(struct dentry *old_dentry, struct inode *dir, struct dentry *new_dentry)
2613 {
2614 return may_link(dir, old_dentry, MAY_LINK);
2615 }
2616
2617 static int selinux_inode_unlink(struct inode *dir, struct dentry *dentry)
2618 {
2619 return may_link(dir, dentry, MAY_UNLINK);
2620 }
2621
2622 static int selinux_inode_symlink(struct inode *dir, struct dentry *dentry, const char *name)
2623 {
2624 return may_create(dir, dentry, SECCLASS_LNK_FILE);
2625 }
2626
2627 static int selinux_inode_mkdir(struct inode *dir, struct dentry *dentry, int mask)
2628 {
2629 return may_create(dir, dentry, SECCLASS_DIR);
2630 }
2631
2632 static int selinux_inode_rmdir(struct inode *dir, struct dentry *dentry)
2633 {
2634 return may_link(dir, dentry, MAY_RMDIR);
2635 }
2636
2637 static int selinux_inode_mknod(struct inode *dir, struct dentry *dentry, int mode, dev_t dev)
2638 {
2639 return may_create(dir, dentry, inode_mode_to_security_class(mode));
2640 }
2641
2642 static int selinux_inode_rename(struct inode *old_inode, struct dentry *old_dentry,
2643 struct inode *new_inode, struct dentry *new_dentry)
2644 {
2645 return may_rename(old_inode, old_dentry, new_inode, new_dentry);
2646 }
2647
2648 static int selinux_inode_readlink(struct dentry *dentry)
2649 {
2650 const struct cred *cred = current_cred();
2651
2652 return dentry_has_perm(cred, dentry, FILE__READ);
2653 }
2654
2655 static int selinux_inode_follow_link(struct dentry *dentry, struct nameidata *nameidata)
2656 {
2657 const struct cred *cred = current_cred();
2658
2659 return dentry_has_perm(cred, dentry, FILE__READ);
2660 }
2661
2662 static int selinux_inode_permission(struct inode *inode, int mask)
2663 {
2664 const struct cred *cred = current_cred();
2665 struct common_audit_data ad;
2666 u32 perms;
2667 bool from_access;
2668 unsigned flags = mask & MAY_NOT_BLOCK;
2669
2670 from_access = mask & MAY_ACCESS;
2671 mask &= (MAY_READ|MAY_WRITE|MAY_EXEC|MAY_APPEND);
2672
2673 /* No permission to check. Existence test. */
2674 if (!mask)
2675 return 0;
2676
2677 COMMON_AUDIT_DATA_INIT(&ad, INODE);
2678 ad.u.inode = inode;
2679
2680 if (from_access)
2681 ad.selinux_audit_data.auditdeny |= FILE__AUDIT_ACCESS;
2682
2683 perms = file_mask_to_av(inode->i_mode, mask);
2684
2685 return inode_has_perm(cred, inode, perms, &ad, flags);
2686 }
2687
2688 static int selinux_inode_setattr(struct dentry *dentry, struct iattr *iattr)
2689 {
2690 const struct cred *cred = current_cred();
2691 unsigned int ia_valid = iattr->ia_valid;
2692
2693 /* ATTR_FORCE is just used for ATTR_KILL_S[UG]ID. */
2694 if (ia_valid & ATTR_FORCE) {
2695 ia_valid &= ~(ATTR_KILL_SUID | ATTR_KILL_SGID | ATTR_MODE |
2696 ATTR_FORCE);
2697 if (!ia_valid)
2698 return 0;
2699 }
2700
2701 if (ia_valid & (ATTR_MODE | ATTR_UID | ATTR_GID |
2702 ATTR_ATIME_SET | ATTR_MTIME_SET | ATTR_TIMES_SET))
2703 return dentry_has_perm(cred, dentry, FILE__SETATTR);
2704
2705 return dentry_has_perm(cred, dentry, FILE__WRITE);
2706 }
2707
2708 static int selinux_inode_getattr(struct vfsmount *mnt, struct dentry *dentry)
2709 {
2710 const struct cred *cred = current_cred();
2711 struct path path;
2712
2713 path.dentry = dentry;
2714 path.mnt = mnt;
2715
2716 return path_has_perm(cred, &path, FILE__GETATTR);
2717 }
2718
2719 static int selinux_inode_setotherxattr(struct dentry *dentry, const char *name)
2720 {
2721 const struct cred *cred = current_cred();
2722
2723 if (!strncmp(name, XATTR_SECURITY_PREFIX,
2724 sizeof XATTR_SECURITY_PREFIX - 1)) {
2725 if (!strcmp(name, XATTR_NAME_CAPS)) {
2726 if (!capable(CAP_SETFCAP))
2727 return -EPERM;
2728 } else if (!capable(CAP_SYS_ADMIN)) {
2729 /* A different attribute in the security namespace.
2730 Restrict to administrator. */
2731 return -EPERM;
2732 }
2733 }
2734
2735 /* Not an attribute we recognize, so just check the
2736 ordinary setattr permission. */
2737 return dentry_has_perm(cred, dentry, FILE__SETATTR);
2738 }
2739
2740 static int selinux_inode_setxattr(struct dentry *dentry, const char *name,
2741 const void *value, size_t size, int flags)
2742 {
2743 struct inode *inode = dentry->d_inode;
2744 struct inode_security_struct *isec = inode->i_security;
2745 struct superblock_security_struct *sbsec;
2746 struct common_audit_data ad;
2747 u32 newsid, sid = current_sid();
2748 int rc = 0;
2749
2750 if (strcmp(name, XATTR_NAME_SELINUX))
2751 return selinux_inode_setotherxattr(dentry, name);
2752
2753 sbsec = inode->i_sb->s_security;
2754 if (!(sbsec->flags & SE_SBLABELSUPP))
2755 return -EOPNOTSUPP;
2756
2757 if (!inode_owner_or_capable(inode))
2758 return -EPERM;
2759
2760 COMMON_AUDIT_DATA_INIT(&ad, DENTRY);
2761 ad.u.dentry = dentry;
2762
2763 rc = avc_has_perm(sid, isec->sid, isec->sclass,
2764 FILE__RELABELFROM, &ad);
2765 if (rc)
2766 return rc;
2767
2768 rc = security_context_to_sid(value, size, &newsid);
2769 if (rc == -EINVAL) {
2770 if (!capable(CAP_MAC_ADMIN))
2771 return rc;
2772 rc = security_context_to_sid_force(value, size, &newsid);
2773 }
2774 if (rc)
2775 return rc;
2776
2777 rc = avc_has_perm(sid, newsid, isec->sclass,
2778 FILE__RELABELTO, &ad);
2779 if (rc)
2780 return rc;
2781
2782 rc = security_validate_transition(isec->sid, newsid, sid,
2783 isec->sclass);
2784 if (rc)
2785 return rc;
2786
2787 return avc_has_perm(newsid,
2788 sbsec->sid,
2789 SECCLASS_FILESYSTEM,
2790 FILESYSTEM__ASSOCIATE,
2791 &ad);
2792 }
2793
2794 static void selinux_inode_post_setxattr(struct dentry *dentry, const char *name,
2795 const void *value, size_t size,
2796 int flags)
2797 {
2798 struct inode *inode = dentry->d_inode;
2799 struct inode_security_struct *isec = inode->i_security;
2800 u32 newsid;
2801 int rc;
2802
2803 if (strcmp(name, XATTR_NAME_SELINUX)) {
2804 /* Not an attribute we recognize, so nothing to do. */
2805 return;
2806 }
2807
2808 rc = security_context_to_sid_force(value, size, &newsid);
2809 if (rc) {
2810 printk(KERN_ERR "SELinux: unable to map context to SID"
2811 "for (%s, %lu), rc=%d\n",
2812 inode->i_sb->s_id, inode->i_ino, -rc);
2813 return;
2814 }
2815
2816 isec->sid = newsid;
2817 return;
2818 }
2819
2820 static int selinux_inode_getxattr(struct dentry *dentry, const char *name)
2821 {
2822 const struct cred *cred = current_cred();
2823
2824 return dentry_has_perm(cred, dentry, FILE__GETATTR);
2825 }
2826
2827 static int selinux_inode_listxattr(struct dentry *dentry)
2828 {
2829 const struct cred *cred = current_cred();
2830
2831 return dentry_has_perm(cred, dentry, FILE__GETATTR);
2832 }
2833
2834 static int selinux_inode_removexattr(struct dentry *dentry, const char *name)
2835 {
2836 if (strcmp(name, XATTR_NAME_SELINUX))
2837 return selinux_inode_setotherxattr(dentry, name);
2838
2839 /* No one is allowed to remove a SELinux security label.
2840 You can change the label, but all data must be labeled. */
2841 return -EACCES;
2842 }
2843
2844 /*
2845 * Copy the inode security context value to the user.
2846 *
2847 * Permission check is handled by selinux_inode_getxattr hook.
2848 */
2849 static int selinux_inode_getsecurity(const struct inode *inode, const char *name, void **buffer, bool alloc)
2850 {
2851 u32 size;
2852 int error;
2853 char *context = NULL;
2854 struct inode_security_struct *isec = inode->i_security;
2855
2856 if (strcmp(name, XATTR_SELINUX_SUFFIX))
2857 return -EOPNOTSUPP;
2858
2859 /*
2860 * If the caller has CAP_MAC_ADMIN, then get the raw context
2861 * value even if it is not defined by current policy; otherwise,
2862 * use the in-core value under current policy.
2863 * Use the non-auditing forms of the permission checks since
2864 * getxattr may be called by unprivileged processes commonly
2865 * and lack of permission just means that we fall back to the
2866 * in-core context value, not a denial.
2867 */
2868 error = selinux_capable(current, current_cred(),
2869 &init_user_ns, CAP_MAC_ADMIN,
2870 SECURITY_CAP_NOAUDIT);
2871 if (!error)
2872 error = security_sid_to_context_force(isec->sid, &context,
2873 &size);
2874 else
2875 error = security_sid_to_context(isec->sid, &context, &size);
2876 if (error)
2877 return error;
2878 error = size;
2879 if (alloc) {
2880 *buffer = context;
2881 goto out_nofree;
2882 }
2883 kfree(context);
2884 out_nofree:
2885 return error;
2886 }
2887
2888 static int selinux_inode_setsecurity(struct inode *inode, const char *name,
2889 const void *value, size_t size, int flags)
2890 {
2891 struct inode_security_struct *isec = inode->i_security;
2892 u32 newsid;
2893 int rc;
2894
2895 if (strcmp(name, XATTR_SELINUX_SUFFIX))
2896 return -EOPNOTSUPP;
2897
2898 if (!value || !size)
2899 return -EACCES;
2900
2901 rc = security_context_to_sid((void *)value, size, &newsid);
2902 if (rc)
2903 return rc;
2904
2905 isec->sid = newsid;
2906 isec->initialized = 1;
2907 return 0;
2908 }
2909
2910 static int selinux_inode_listsecurity(struct inode *inode, char *buffer, size_t buffer_size)
2911 {
2912 const int len = sizeof(XATTR_NAME_SELINUX);
2913 if (buffer && len <= buffer_size)
2914 memcpy(buffer, XATTR_NAME_SELINUX, len);
2915 return len;
2916 }
2917
2918 static void selinux_inode_getsecid(const struct inode *inode, u32 *secid)
2919 {
2920 struct inode_security_struct *isec = inode->i_security;
2921 *secid = isec->sid;
2922 }
2923
2924 /* file security operations */
2925
2926 static int selinux_revalidate_file_permission(struct file *file, int mask)
2927 {
2928 const struct cred *cred = current_cred();
2929 struct inode *inode = file->f_path.dentry->d_inode;
2930
2931 /* file_mask_to_av won't add FILE__WRITE if MAY_APPEND is set */
2932 if ((file->f_flags & O_APPEND) && (mask & MAY_WRITE))
2933 mask |= MAY_APPEND;
2934
2935 return file_has_perm(cred, file,
2936 file_mask_to_av(inode->i_mode, mask));
2937 }
2938
2939 static int selinux_file_permission(struct file *file, int mask)
2940 {
2941 struct inode *inode = file->f_path.dentry->d_inode;
2942 struct file_security_struct *fsec = file->f_security;
2943 struct inode_security_struct *isec = inode->i_security;
2944 u32 sid = current_sid();
2945
2946 if (!mask)
2947 /* No permission to check. Existence test. */
2948 return 0;
2949
2950 if (sid == fsec->sid && fsec->isid == isec->sid &&
2951 fsec->pseqno == avc_policy_seqno())
2952 /* No change since dentry_open check. */
2953 return 0;
2954
2955 return selinux_revalidate_file_permission(file, mask);
2956 }
2957
2958 static int selinux_file_alloc_security(struct file *file)
2959 {
2960 return file_alloc_security(file);
2961 }
2962
2963 static void selinux_file_free_security(struct file *file)
2964 {
2965 file_free_security(file);
2966 }
2967
2968 static int selinux_file_ioctl(struct file *file, unsigned int cmd,
2969 unsigned long arg)
2970 {
2971 const struct cred *cred = current_cred();
2972 int error = 0;
2973
2974 switch (cmd) {
2975 case FIONREAD:
2976 /* fall through */
2977 case FIBMAP:
2978 /* fall through */
2979 case FIGETBSZ:
2980 /* fall through */
2981 case EXT2_IOC_GETFLAGS:
2982 /* fall through */
2983 case EXT2_IOC_GETVERSION:
2984 error = file_has_perm(cred, file, FILE__GETATTR);
2985 break;
2986
2987 case EXT2_IOC_SETFLAGS:
2988 /* fall through */
2989 case EXT2_IOC_SETVERSION:
2990 error = file_has_perm(cred, file, FILE__SETATTR);
2991 break;
2992
2993 /* sys_ioctl() checks */
2994 case FIONBIO:
2995 /* fall through */
2996 case FIOASYNC:
2997 error = file_has_perm(cred, file, 0);
2998 break;
2999
3000 case KDSKBENT:
3001 case KDSKBSENT:
3002 error = task_has_capability(current, cred, CAP_SYS_TTY_CONFIG,
3003 SECURITY_CAP_AUDIT);
3004 break;
3005
3006 /* default case assumes that the command will go
3007 * to the file's ioctl() function.
3008 */
3009 default:
3010 error = file_has_perm(cred, file, FILE__IOCTL);
3011 }
3012 return error;
3013 }
3014
3015 static int default_noexec;
3016
3017 static int file_map_prot_check(struct file *file, unsigned long prot, int shared)
3018 {
3019 const struct cred *cred = current_cred();
3020 int rc = 0;
3021
3022 if (default_noexec &&
3023 (prot & PROT_EXEC) && (!file || (!shared && (prot & PROT_WRITE)))) {
3024 /*
3025 * We are making executable an anonymous mapping or a
3026 * private file mapping that will also be writable.
3027 * This has an additional check.
3028 */
3029 rc = cred_has_perm(cred, cred, PROCESS__EXECMEM);
3030 if (rc)
3031 goto error;
3032 }
3033
3034 if (file) {
3035 /* read access is always possible with a mapping */
3036 u32 av = FILE__READ;
3037
3038 /* write access only matters if the mapping is shared */
3039 if (shared && (prot & PROT_WRITE))
3040 av |= FILE__WRITE;
3041
3042 if (prot & PROT_EXEC)
3043 av |= FILE__EXECUTE;
3044
3045 return file_has_perm(cred, file, av);
3046 }
3047
3048 error:
3049 return rc;
3050 }
3051
3052 static int selinux_file_mmap(struct file *file, unsigned long reqprot,
3053 unsigned long prot, unsigned long flags,
3054 unsigned long addr, unsigned long addr_only)
3055 {
3056 int rc = 0;
3057 u32 sid = current_sid();
3058
3059 /*
3060 * notice that we are intentionally putting the SELinux check before
3061 * the secondary cap_file_mmap check. This is such a likely attempt
3062 * at bad behaviour/exploit that we always want to get the AVC, even
3063 * if DAC would have also denied the operation.
3064 */
3065 if (addr < CONFIG_LSM_MMAP_MIN_ADDR) {
3066 rc = avc_has_perm(sid, sid, SECCLASS_MEMPROTECT,
3067 MEMPROTECT__MMAP_ZERO, NULL);
3068 if (rc)
3069 return rc;
3070 }
3071
3072 /* do DAC check on address space usage */
3073 rc = cap_file_mmap(file, reqprot, prot, flags, addr, addr_only);
3074 if (rc || addr_only)
3075 return rc;
3076
3077 if (selinux_checkreqprot)
3078 prot = reqprot;
3079
3080 return file_map_prot_check(file, prot,
3081 (flags & MAP_TYPE) == MAP_SHARED);
3082 }
3083
3084 static int selinux_file_mprotect(struct vm_area_struct *vma,
3085 unsigned long reqprot,
3086 unsigned long prot)
3087 {
3088 const struct cred *cred = current_cred();
3089
3090 if (selinux_checkreqprot)
3091 prot = reqprot;
3092
3093 if (default_noexec &&
3094 (prot & PROT_EXEC) && !(vma->vm_flags & VM_EXEC)) {
3095 int rc = 0;
3096 if (vma->vm_start >= vma->vm_mm->start_brk &&
3097 vma->vm_end <= vma->vm_mm->brk) {
3098 rc = cred_has_perm(cred, cred, PROCESS__EXECHEAP);
3099 } else if (!vma->vm_file &&
3100 vma->vm_start <= vma->vm_mm->start_stack &&
3101 vma->vm_end >= vma->vm_mm->start_stack) {
3102 rc = current_has_perm(current, PROCESS__EXECSTACK);
3103 } else if (vma->vm_file && vma->anon_vma) {
3104 /*
3105 * We are making executable a file mapping that has
3106 * had some COW done. Since pages might have been
3107 * written, check ability to execute the possibly
3108 * modified content. This typically should only
3109 * occur for text relocations.
3110 */
3111 rc = file_has_perm(cred, vma->vm_file, FILE__EXECMOD);
3112 }
3113 if (rc)
3114 return rc;
3115 }
3116
3117 return file_map_prot_check(vma->vm_file, prot, vma->vm_flags&VM_SHARED);
3118 }
3119
3120 static int selinux_file_lock(struct file *file, unsigned int cmd)
3121 {
3122 const struct cred *cred = current_cred();
3123
3124 return file_has_perm(cred, file, FILE__LOCK);
3125 }
3126
3127 static int selinux_file_fcntl(struct file *file, unsigned int cmd,
3128 unsigned long arg)
3129 {
3130 const struct cred *cred = current_cred();
3131 int err = 0;
3132
3133 switch (cmd) {
3134 case F_SETFL:
3135 if (!file->f_path.dentry || !file->f_path.dentry->d_inode) {
3136 err = -EINVAL;
3137 break;
3138 }
3139
3140 if ((file->f_flags & O_APPEND) && !(arg & O_APPEND)) {
3141 err = file_has_perm(cred, file, FILE__WRITE);
3142 break;
3143 }
3144 /* fall through */
3145 case F_SETOWN:
3146 case F_SETSIG:
3147 case F_GETFL:
3148 case F_GETOWN:
3149 case F_GETSIG:
3150 /* Just check FD__USE permission */
3151 err = file_has_perm(cred, file, 0);
3152 break;
3153 case F_GETLK:
3154 case F_SETLK:
3155 case F_SETLKW:
3156 #if BITS_PER_LONG == 32
3157 case F_GETLK64:
3158 case F_SETLK64:
3159 case F_SETLKW64:
3160 #endif
3161 if (!file->f_path.dentry || !file->f_path.dentry->d_inode) {
3162 err = -EINVAL;
3163 break;
3164 }
3165 err = file_has_perm(cred, file, FILE__LOCK);
3166 break;
3167 }
3168
3169 return err;
3170 }
3171
3172 static int selinux_file_set_fowner(struct file *file)
3173 {
3174 struct file_security_struct *fsec;
3175
3176 fsec = file->f_security;
3177 fsec->fown_sid = current_sid();
3178
3179 return 0;
3180 }
3181
3182 static int selinux_file_send_sigiotask(struct task_struct *tsk,
3183 struct fown_struct *fown, int signum)
3184 {
3185 struct file *file;
3186 u32 sid = task_sid(tsk);
3187 u32 perm;
3188 struct file_security_struct *fsec;
3189
3190 /* struct fown_struct is never outside the context of a struct file */
3191 file = container_of(fown, struct file, f_owner);
3192
3193 fsec = file->f_security;
3194
3195 if (!signum)
3196 perm = signal_to_av(SIGIO); /* as per send_sigio_to_task */
3197 else
3198 perm = signal_to_av(signum);
3199
3200 return avc_has_perm(fsec->fown_sid, sid,
3201 SECCLASS_PROCESS, perm, NULL);
3202 }
3203
3204 static int selinux_file_receive(struct file *file)
3205 {
3206 const struct cred *cred = current_cred();
3207
3208 return file_has_perm(cred, file, file_to_av(file));
3209 }
3210
3211 static int selinux_dentry_open(struct file *file, const struct cred *cred)
3212 {
3213 struct file_security_struct *fsec;
3214 struct inode *inode;
3215 struct inode_security_struct *isec;
3216
3217 inode = file->f_path.dentry->d_inode;
3218 fsec = file->f_security;
3219 isec = inode->i_security;
3220 /*
3221 * Save inode label and policy sequence number
3222 * at open-time so that selinux_file_permission
3223 * can determine whether revalidation is necessary.
3224 * Task label is already saved in the file security
3225 * struct as its SID.
3226 */
3227 fsec->isid = isec->sid;
3228 fsec->pseqno = avc_policy_seqno();
3229 /*
3230 * Since the inode label or policy seqno may have changed
3231 * between the selinux_inode_permission check and the saving
3232 * of state above, recheck that access is still permitted.
3233 * Otherwise, access might never be revalidated against the
3234 * new inode label or new policy.
3235 * This check is not redundant - do not remove.
3236 */
3237 return inode_has_perm_noadp(cred, inode, open_file_to_av(file), 0);
3238 }
3239
3240 /* task security operations */
3241
3242 static int selinux_task_create(unsigned long clone_flags)
3243 {
3244 return current_has_perm(current, PROCESS__FORK);
3245 }
3246
3247 /*
3248 * allocate the SELinux part of blank credentials
3249 */
3250 static int selinux_cred_alloc_blank(struct cred *cred, gfp_t gfp)
3251 {
3252 struct task_security_struct *tsec;
3253
3254 tsec = kzalloc(sizeof(struct task_security_struct), gfp);
3255 if (!tsec)
3256 return -ENOMEM;
3257
3258 cred->security = tsec;
3259 return 0;
3260 }
3261
3262 /*
3263 * detach and free the LSM part of a set of credentials
3264 */
3265 static void selinux_cred_free(struct cred *cred)
3266 {
3267 struct task_security_struct *tsec = cred->security;
3268
3269 /*
3270 * cred->security == NULL if security_cred_alloc_blank() or
3271 * security_prepare_creds() returned an error.
3272 */
3273 BUG_ON(cred->security && (unsigned long) cred->security < PAGE_SIZE);
3274 cred->security = (void *) 0x7UL;
3275 kfree(tsec);
3276 }
3277
3278 /*
3279 * prepare a new set of credentials for modification
3280 */
3281 static int selinux_cred_prepare(struct cred *new, const struct cred *old,
3282 gfp_t gfp)
3283 {
3284 const struct task_security_struct *old_tsec;
3285 struct task_security_struct *tsec;
3286
3287 old_tsec = old->security;
3288
3289 tsec = kmemdup(old_tsec, sizeof(struct task_security_struct), gfp);
3290 if (!tsec)
3291 return -ENOMEM;
3292
3293 new->security = tsec;
3294 return 0;
3295 }
3296
3297 /*
3298 * transfer the SELinux data to a blank set of creds
3299 */
3300 static void selinux_cred_transfer(struct cred *new, const struct cred *old)
3301 {
3302 const struct task_security_struct *old_tsec = old->security;
3303 struct task_security_struct *tsec = new->security;
3304
3305 *tsec = *old_tsec;
3306 }
3307
3308 /*
3309 * set the security data for a kernel service
3310 * - all the creation contexts are set to unlabelled
3311 */
3312 static int selinux_kernel_act_as(struct cred *new, u32 secid)
3313 {
3314 struct task_security_struct *tsec = new->security;
3315 u32 sid = current_sid();
3316 int ret;
3317
3318 ret = avc_has_perm(sid, secid,
3319 SECCLASS_KERNEL_SERVICE,
3320 KERNEL_SERVICE__USE_AS_OVERRIDE,
3321 NULL);
3322 if (ret == 0) {
3323 tsec->sid = secid;
3324 tsec->create_sid = 0;
3325 tsec->keycreate_sid = 0;
3326 tsec->sockcreate_sid = 0;
3327 }
3328 return ret;
3329 }
3330
3331 /*
3332 * set the file creation context in a security record to the same as the
3333 * objective context of the specified inode
3334 */
3335 static int selinux_kernel_create_files_as(struct cred *new, struct inode *inode)
3336 {
3337 struct inode_security_struct *isec = inode->i_security;
3338 struct task_security_struct *tsec = new->security;
3339 u32 sid = current_sid();
3340 int ret;
3341
3342 ret = avc_has_perm(sid, isec->sid,
3343 SECCLASS_KERNEL_SERVICE,
3344 KERNEL_SERVICE__CREATE_FILES_AS,
3345 NULL);
3346
3347 if (ret == 0)
3348 tsec->create_sid = isec->sid;
3349 return ret;
3350 }
3351
3352 static int selinux_kernel_module_request(char *kmod_name)
3353 {
3354 u32 sid;
3355 struct common_audit_data ad;
3356
3357 sid = task_sid(current);
3358
3359 COMMON_AUDIT_DATA_INIT(&ad, KMOD);
3360 ad.u.kmod_name = kmod_name;
3361
3362 return avc_has_perm(sid, SECINITSID_KERNEL, SECCLASS_SYSTEM,
3363 SYSTEM__MODULE_REQUEST, &ad);
3364 }
3365
3366 static int selinux_task_setpgid(struct task_struct *p, pid_t pgid)
3367 {
3368 return current_has_perm(p, PROCESS__SETPGID);
3369 }
3370
3371 static int selinux_task_getpgid(struct task_struct *p)
3372 {
3373 return current_has_perm(p, PROCESS__GETPGID);
3374 }
3375
3376 static int selinux_task_getsid(struct task_struct *p)
3377 {
3378 return current_has_perm(p, PROCESS__GETSESSION);
3379 }
3380
3381 static void selinux_task_getsecid(struct task_struct *p, u32 *secid)
3382 {
3383 *secid = task_sid(p);
3384 }
3385
3386 static int selinux_task_setnice(struct task_struct *p, int nice)
3387 {
3388 int rc;
3389
3390 rc = cap_task_setnice(p, nice);
3391 if (rc)
3392 return rc;
3393
3394 return current_has_perm(p, PROCESS__SETSCHED);
3395 }
3396
3397 static int selinux_task_setioprio(struct task_struct *p, int ioprio)
3398 {
3399 int rc;
3400
3401 rc = cap_task_setioprio(p, ioprio);
3402 if (rc)
3403 return rc;
3404
3405 return current_has_perm(p, PROCESS__SETSCHED);
3406 }
3407
3408 static int selinux_task_getioprio(struct task_struct *p)
3409 {
3410 return current_has_perm(p, PROCESS__GETSCHED);
3411 }
3412
3413 static int selinux_task_setrlimit(struct task_struct *p, unsigned int resource,
3414 struct rlimit *new_rlim)
3415 {
3416 struct rlimit *old_rlim = p->signal->rlim + resource;
3417
3418 /* Control the ability to change the hard limit (whether
3419 lowering or raising it), so that the hard limit can
3420 later be used as a safe reset point for the soft limit
3421 upon context transitions. See selinux_bprm_committing_creds. */
3422 if (old_rlim->rlim_max != new_rlim->rlim_max)
3423 return current_has_perm(p, PROCESS__SETRLIMIT);
3424
3425 return 0;
3426 }
3427
3428 static int selinux_task_setscheduler(struct task_struct *p)
3429 {
3430 int rc;
3431
3432 rc = cap_task_setscheduler(p);
3433 if (rc)
3434 return rc;
3435
3436 return current_has_perm(p, PROCESS__SETSCHED);
3437 }
3438
3439 static int selinux_task_getscheduler(struct task_struct *p)
3440 {
3441 return current_has_perm(p, PROCESS__GETSCHED);
3442 }
3443
3444 static int selinux_task_movememory(struct task_struct *p)
3445 {
3446 return current_has_perm(p, PROCESS__SETSCHED);
3447 }
3448
3449 static int selinux_task_kill(struct task_struct *p, struct siginfo *info,
3450 int sig, u32 secid)
3451 {
3452 u32 perm;
3453 int rc;
3454
3455 if (!sig)
3456 perm = PROCESS__SIGNULL; /* null signal; existence test */
3457 else
3458 perm = signal_to_av(sig);
3459 if (secid)
3460 rc = avc_has_perm(secid, task_sid(p),
3461 SECCLASS_PROCESS, perm, NULL);
3462 else
3463 rc = current_has_perm(p, perm);
3464 return rc;
3465 }
3466
3467 static int selinux_task_wait(struct task_struct *p)
3468 {
3469 return task_has_perm(p, current, PROCESS__SIGCHLD);
3470 }
3471
3472 static void selinux_task_to_inode(struct task_struct *p,
3473 struct inode *inode)
3474 {
3475 struct inode_security_struct *isec = inode->i_security;
3476 u32 sid = task_sid(p);
3477
3478 isec->sid = sid;
3479 isec->initialized = 1;
3480 }
3481
3482 /* Returns error only if unable to parse addresses */
3483 static int selinux_parse_skb_ipv4(struct sk_buff *skb,
3484 struct common_audit_data *ad, u8 *proto)
3485 {
3486 int offset, ihlen, ret = -EINVAL;
3487 struct iphdr _iph, *ih;
3488
3489 offset = skb_network_offset(skb);
3490 ih = skb_header_pointer(skb, offset, sizeof(_iph), &_iph);
3491 if (ih == NULL)
3492 goto out;
3493
3494 ihlen = ih->ihl * 4;
3495 if (ihlen < sizeof(_iph))
3496 goto out;
3497
3498 ad->u.net.v4info.saddr = ih->saddr;
3499 ad->u.net.v4info.daddr = ih->daddr;
3500 ret = 0;
3501
3502 if (proto)
3503 *proto = ih->protocol;
3504
3505 switch (ih->protocol) {
3506 case IPPROTO_TCP: {
3507 struct tcphdr _tcph, *th;
3508
3509 if (ntohs(ih->frag_off) & IP_OFFSET)
3510 break;
3511
3512 offset += ihlen;
3513 th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph);
3514 if (th == NULL)
3515 break;
3516
3517 ad->u.net.sport = th->source;
3518 ad->u.net.dport = th->dest;
3519 break;
3520 }
3521
3522 case IPPROTO_UDP: {
3523 struct udphdr _udph, *uh;
3524
3525 if (ntohs(ih->frag_off) & IP_OFFSET)
3526 break;
3527
3528 offset += ihlen;
3529 uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph);
3530 if (uh == NULL)
3531 break;
3532
3533 ad->u.net.sport = uh->source;
3534 ad->u.net.dport = uh->dest;
3535 break;
3536 }
3537
3538 case IPPROTO_DCCP: {
3539 struct dccp_hdr _dccph, *dh;
3540
3541 if (ntohs(ih->frag_off) & IP_OFFSET)
3542 break;
3543
3544 offset += ihlen;
3545 dh = skb_header_pointer(skb, offset, sizeof(_dccph), &_dccph);
3546 if (dh == NULL)
3547 break;
3548
3549 ad->u.net.sport = dh->dccph_sport;
3550 ad->u.net.dport = dh->dccph_dport;
3551 break;
3552 }
3553
3554 default:
3555 break;
3556 }
3557 out:
3558 return ret;
3559 }
3560
3561 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
3562
3563 /* Returns error only if unable to parse addresses */
3564 static int selinux_parse_skb_ipv6(struct sk_buff *skb,
3565 struct common_audit_data *ad, u8 *proto)
3566 {
3567 u8 nexthdr;
3568 int ret = -EINVAL, offset;
3569 struct ipv6hdr _ipv6h, *ip6;
3570
3571 offset = skb_network_offset(skb);
3572 ip6 = skb_header_pointer(skb, offset, sizeof(_ipv6h), &_ipv6h);
3573 if (ip6 == NULL)
3574 goto out;
3575
3576 ipv6_addr_copy(&ad->u.net.v6info.saddr, &ip6->saddr);
3577 ipv6_addr_copy(&ad->u.net.v6info.daddr, &ip6->daddr);
3578 ret = 0;
3579
3580 nexthdr = ip6->nexthdr;
3581 offset += sizeof(_ipv6h);
3582 offset = ipv6_skip_exthdr(skb, offset, &nexthdr);
3583 if (offset < 0)
3584 goto out;
3585
3586 if (proto)
3587 *proto = nexthdr;
3588
3589 switch (nexthdr) {
3590 case IPPROTO_TCP: {
3591 struct tcphdr _tcph, *th;
3592
3593 th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph);
3594 if (th == NULL)
3595 break;
3596
3597 ad->u.net.sport = th->source;
3598 ad->u.net.dport = th->dest;
3599 break;
3600 }
3601
3602 case IPPROTO_UDP: {
3603 struct udphdr _udph, *uh;
3604
3605 uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph);
3606 if (uh == NULL)
3607 break;
3608
3609 ad->u.net.sport = uh->source;
3610 ad->u.net.dport = uh->dest;
3611 break;
3612 }
3613
3614 case IPPROTO_DCCP: {
3615 struct dccp_hdr _dccph, *dh;
3616
3617 dh = skb_header_pointer(skb, offset, sizeof(_dccph), &_dccph);
3618 if (dh == NULL)
3619 break;
3620
3621 ad->u.net.sport = dh->dccph_sport;
3622 ad->u.net.dport = dh->dccph_dport;
3623 break;
3624 }
3625
3626 /* includes fragments */
3627 default:
3628 break;
3629 }
3630 out:
3631 return ret;
3632 }
3633
3634 #endif /* IPV6 */
3635
3636 static int selinux_parse_skb(struct sk_buff *skb, struct common_audit_data *ad,
3637 char **_addrp, int src, u8 *proto)
3638 {
3639 char *addrp;
3640 int ret;
3641
3642 switch (ad->u.net.family) {
3643 case PF_INET:
3644 ret = selinux_parse_skb_ipv4(skb, ad, proto);
3645 if (ret)
3646 goto parse_error;
3647 addrp = (char *)(src ? &ad->u.net.v4info.saddr :
3648 &ad->u.net.v4info.daddr);
3649 goto okay;
3650
3651 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
3652 case PF_INET6:
3653 ret = selinux_parse_skb_ipv6(skb, ad, proto);
3654 if (ret)
3655 goto parse_error;
3656 addrp = (char *)(src ? &ad->u.net.v6info.saddr :
3657 &ad->u.net.v6info.daddr);
3658 goto okay;
3659 #endif /* IPV6 */
3660 default:
3661 addrp = NULL;
3662 goto okay;
3663 }
3664
3665 parse_error:
3666 printk(KERN_WARNING
3667 "SELinux: failure in selinux_parse_skb(),"
3668 " unable to parse packet\n");
3669 return ret;
3670
3671 okay:
3672 if (_addrp)
3673 *_addrp = addrp;
3674 return 0;
3675 }
3676
3677 /**
3678 * selinux_skb_peerlbl_sid - Determine the peer label of a packet
3679 * @skb: the packet
3680 * @family: protocol family
3681 * @sid: the packet's peer label SID
3682 *
3683 * Description:
3684 * Check the various different forms of network peer labeling and determine
3685 * the peer label/SID for the packet; most of the magic actually occurs in
3686 * the security server function security_net_peersid_cmp(). The function
3687 * returns zero if the value in @sid is valid (although it may be SECSID_NULL)
3688 * or -EACCES if @sid is invalid due to inconsistencies with the different
3689 * peer labels.
3690 *
3691 */
3692 static int selinux_skb_peerlbl_sid(struct sk_buff *skb, u16 family, u32 *sid)
3693 {
3694 int err;
3695 u32 xfrm_sid;
3696 u32 nlbl_sid;
3697 u32 nlbl_type;
3698
3699 selinux_skb_xfrm_sid(skb, &xfrm_sid);
3700 selinux_netlbl_skbuff_getsid(skb, family, &nlbl_type, &nlbl_sid);
3701
3702 err = security_net_peersid_resolve(nlbl_sid, nlbl_type, xfrm_sid, sid);
3703 if (unlikely(err)) {
3704 printk(KERN_WARNING
3705 "SELinux: failure in selinux_skb_peerlbl_sid(),"
3706 " unable to determine packet's peer label\n");
3707 return -EACCES;
3708 }
3709
3710 return 0;
3711 }
3712
3713 /* socket security operations */
3714
3715 static int socket_sockcreate_sid(const struct task_security_struct *tsec,
3716 u16 secclass, u32 *socksid)
3717 {
3718 if (tsec->sockcreate_sid > SECSID_NULL) {
3719 *socksid = tsec->sockcreate_sid;
3720 return 0;
3721 }
3722
3723 return security_transition_sid(tsec->sid, tsec->sid, secclass, NULL,
3724 socksid);
3725 }
3726
3727 static int sock_has_perm(struct task_struct *task, struct sock *sk, u32 perms)
3728 {
3729 struct sk_security_struct *sksec = sk->sk_security;
3730 struct common_audit_data ad;
3731 u32 tsid = task_sid(task);
3732
3733 if (sksec->sid == SECINITSID_KERNEL)
3734 return 0;
3735
3736 COMMON_AUDIT_DATA_INIT(&ad, NET);
3737 ad.u.net.sk = sk;
3738
3739 return avc_has_perm(tsid, sksec->sid, sksec->sclass, perms, &ad);
3740 }
3741
3742 static int selinux_socket_create(int family, int type,
3743 int protocol, int kern)
3744 {
3745 const struct task_security_struct *tsec = current_security();
3746 u32 newsid;
3747 u16 secclass;
3748 int rc;
3749
3750 if (kern)
3751 return 0;
3752
3753 secclass = socket_type_to_security_class(family, type, protocol);
3754 rc = socket_sockcreate_sid(tsec, secclass, &newsid);
3755 if (rc)
3756 return rc;
3757
3758 return avc_has_perm(tsec->sid, newsid, secclass, SOCKET__CREATE, NULL);
3759 }
3760
3761 static int selinux_socket_post_create(struct socket *sock, int family,
3762 int type, int protocol, int kern)
3763 {
3764 const struct task_security_struct *tsec = current_security();
3765 struct inode_security_struct *isec = SOCK_INODE(sock)->i_security;
3766 struct sk_security_struct *sksec;
3767 int err = 0;
3768
3769 isec->sclass = socket_type_to_security_class(family, type, protocol);
3770
3771 if (kern)
3772 isec->sid = SECINITSID_KERNEL;
3773 else {
3774 err = socket_sockcreate_sid(tsec, isec->sclass, &(isec->sid));
3775 if (err)
3776 return err;
3777 }
3778
3779 isec->initialized = 1;
3780
3781 if (sock->sk) {
3782 sksec = sock->sk->sk_security;
3783 sksec->sid = isec->sid;
3784 sksec->sclass = isec->sclass;
3785 err = selinux_netlbl_socket_post_create(sock->sk, family);
3786 }
3787
3788 return err;
3789 }
3790
3791 /* Range of port numbers used to automatically bind.
3792 Need to determine whether we should perform a name_bind
3793 permission check between the socket and the port number. */
3794
3795 static int selinux_socket_bind(struct socket *sock, struct sockaddr *address, int addrlen)
3796 {
3797 struct sock *sk = sock->sk;
3798 u16 family;
3799 int err;
3800
3801 err = sock_has_perm(current, sk, SOCKET__BIND);
3802 if (err)
3803 goto out;
3804
3805 /*
3806 * If PF_INET or PF_INET6, check name_bind permission for the port.
3807 * Multiple address binding for SCTP is not supported yet: we just
3808 * check the first address now.
3809 */
3810 family = sk->sk_family;
3811 if (family == PF_INET || family == PF_INET6) {
3812 char *addrp;
3813 struct sk_security_struct *sksec = sk->sk_security;
3814 struct common_audit_data ad;
3815 struct sockaddr_in *addr4 = NULL;
3816 struct sockaddr_in6 *addr6 = NULL;
3817 unsigned short snum;
3818 u32 sid, node_perm;
3819
3820 if (family == PF_INET) {
3821 addr4 = (struct sockaddr_in *)address;
3822 snum = ntohs(addr4->sin_port);
3823 addrp = (char *)&addr4->sin_addr.s_addr;
3824 } else {
3825 addr6 = (struct sockaddr_in6 *)address;
3826 snum = ntohs(addr6->sin6_port);
3827 addrp = (char *)&addr6->sin6_addr.s6_addr;
3828 }
3829
3830 if (snum) {
3831 int low, high;
3832
3833 inet_get_local_port_range(&low, &high);
3834
3835 if (snum < max(PROT_SOCK, low) || snum > high) {
3836 err = sel_netport_sid(sk->sk_protocol,
3837 snum, &sid);
3838 if (err)
3839 goto out;
3840 COMMON_AUDIT_DATA_INIT(&ad, NET);
3841 ad.u.net.sport = htons(snum);
3842 ad.u.net.family = family;
3843 err = avc_has_perm(sksec->sid, sid,
3844 sksec->sclass,
3845 SOCKET__NAME_BIND, &ad);
3846 if (err)
3847 goto out;
3848 }
3849 }
3850
3851 switch (sksec->sclass) {
3852 case SECCLASS_TCP_SOCKET:
3853 node_perm = TCP_SOCKET__NODE_BIND;
3854 break;
3855
3856 case SECCLASS_UDP_SOCKET:
3857 node_perm = UDP_SOCKET__NODE_BIND;
3858 break;
3859
3860 case SECCLASS_DCCP_SOCKET:
3861 node_perm = DCCP_SOCKET__NODE_BIND;
3862 break;
3863
3864 default:
3865 node_perm = RAWIP_SOCKET__NODE_BIND;
3866 break;
3867 }
3868
3869 err = sel_netnode_sid(addrp, family, &sid);
3870 if (err)
3871 goto out;
3872
3873 COMMON_AUDIT_DATA_INIT(&ad, NET);
3874 ad.u.net.sport = htons(snum);
3875 ad.u.net.family = family;
3876
3877 if (family == PF_INET)
3878 ad.u.net.v4info.saddr = addr4->sin_addr.s_addr;
3879 else
3880 ipv6_addr_copy(&ad.u.net.v6info.saddr, &addr6->sin6_addr);
3881
3882 err = avc_has_perm(sksec->sid, sid,
3883 sksec->sclass, node_perm, &ad);
3884 if (err)
3885 goto out;
3886 }
3887 out:
3888 return err;
3889 }
3890
3891 static int selinux_socket_connect(struct socket *sock, struct sockaddr *address, int addrlen)
3892 {
3893 struct sock *sk = sock->sk;
3894 struct sk_security_struct *sksec = sk->sk_security;
3895 int err;
3896
3897 err = sock_has_perm(current, sk, SOCKET__CONNECT);
3898 if (err)
3899 return err;
3900
3901 /*
3902 * If a TCP or DCCP socket, check name_connect permission for the port.
3903 */
3904 if (sksec->sclass == SECCLASS_TCP_SOCKET ||
3905 sksec->sclass == SECCLASS_DCCP_SOCKET) {
3906 struct common_audit_data ad;
3907 struct sockaddr_in *addr4 = NULL;
3908 struct sockaddr_in6 *addr6 = NULL;
3909 unsigned short snum;
3910 u32 sid, perm;
3911
3912 if (sk->sk_family == PF_INET) {
3913 addr4 = (struct sockaddr_in *)address;
3914 if (addrlen < sizeof(struct sockaddr_in))
3915 return -EINVAL;
3916 snum = ntohs(addr4->sin_port);
3917 } else {
3918 addr6 = (struct sockaddr_in6 *)address;
3919 if (addrlen < SIN6_LEN_RFC2133)
3920 return -EINVAL;
3921 snum = ntohs(addr6->sin6_port);
3922 }
3923
3924 err = sel_netport_sid(sk->sk_protocol, snum, &sid);
3925 if (err)
3926 goto out;
3927
3928 perm = (sksec->sclass == SECCLASS_TCP_SOCKET) ?
3929 TCP_SOCKET__NAME_CONNECT : DCCP_SOCKET__NAME_CONNECT;
3930
3931 COMMON_AUDIT_DATA_INIT(&ad, NET);
3932 ad.u.net.dport = htons(snum);
3933 ad.u.net.family = sk->sk_family;
3934 err = avc_has_perm(sksec->sid, sid, sksec->sclass, perm, &ad);
3935 if (err)
3936 goto out;
3937 }
3938
3939 err = selinux_netlbl_socket_connect(sk, address);
3940
3941 out:
3942 return err;
3943 }
3944
3945 static int selinux_socket_listen(struct socket *sock, int backlog)
3946 {
3947 return sock_has_perm(current, sock->sk, SOCKET__LISTEN);
3948 }
3949
3950 static int selinux_socket_accept(struct socket *sock, struct socket *newsock)
3951 {
3952 int err;
3953 struct inode_security_struct *isec;
3954 struct inode_security_struct *newisec;
3955
3956 err = sock_has_perm(current, sock->sk, SOCKET__ACCEPT);
3957 if (err)
3958 return err;
3959
3960 newisec = SOCK_INODE(newsock)->i_security;
3961
3962 isec = SOCK_INODE(sock)->i_security;
3963 newisec->sclass = isec->sclass;
3964 newisec->sid = isec->sid;
3965 newisec->initialized = 1;
3966
3967 return 0;
3968 }
3969
3970 static int selinux_socket_sendmsg(struct socket *sock, struct msghdr *msg,
3971 int size)
3972 {
3973 return sock_has_perm(current, sock->sk, SOCKET__WRITE);
3974 }
3975
3976 static int selinux_socket_recvmsg(struct socket *sock, struct msghdr *msg,
3977 int size, int flags)
3978 {
3979 return sock_has_perm(current, sock->sk, SOCKET__READ);
3980 }
3981
3982 static int selinux_socket_getsockname(struct socket *sock)
3983 {
3984 return sock_has_perm(current, sock->sk, SOCKET__GETATTR);
3985 }
3986
3987 static int selinux_socket_getpeername(struct socket *sock)
3988 {
3989 return sock_has_perm(current, sock->sk, SOCKET__GETATTR);
3990 }
3991
3992 static int selinux_socket_setsockopt(struct socket *sock, int level, int optname)
3993 {
3994 int err;
3995
3996 err = sock_has_perm(current, sock->sk, SOCKET__SETOPT);
3997 if (err)
3998 return err;
3999
4000 return selinux_netlbl_socket_setsockopt(sock, level, optname);
4001 }
4002
4003 static int selinux_socket_getsockopt(struct socket *sock, int level,
4004 int optname)
4005 {
4006 return sock_has_perm(current, sock->sk, SOCKET__GETOPT);
4007 }
4008
4009 static int selinux_socket_shutdown(struct socket *sock, int how)
4010 {
4011 return sock_has_perm(current, sock->sk, SOCKET__SHUTDOWN);
4012 }
4013
4014 static int selinux_socket_unix_stream_connect(struct sock *sock,
4015 struct sock *other,
4016 struct sock *newsk)
4017 {
4018 struct sk_security_struct *sksec_sock = sock->sk_security;
4019 struct sk_security_struct *sksec_other = other->sk_security;
4020 struct sk_security_struct *sksec_new = newsk->sk_security;
4021 struct common_audit_data ad;
4022 int err;
4023
4024 COMMON_AUDIT_DATA_INIT(&ad, NET);
4025 ad.u.net.sk = other;
4026
4027 err = avc_has_perm(sksec_sock->sid, sksec_other->sid,
4028 sksec_other->sclass,
4029 UNIX_STREAM_SOCKET__CONNECTTO, &ad);
4030 if (err)
4031 return err;
4032
4033 /* server child socket */
4034 sksec_new->peer_sid = sksec_sock->sid;
4035 err = security_sid_mls_copy(sksec_other->sid, sksec_sock->sid,
4036 &sksec_new->sid);
4037 if (err)
4038 return err;
4039
4040 /* connecting socket */
4041 sksec_sock->peer_sid = sksec_new->sid;
4042
4043 return 0;
4044 }
4045
4046 static int selinux_socket_unix_may_send(struct socket *sock,
4047 struct socket *other)
4048 {
4049 struct sk_security_struct *ssec = sock->sk->sk_security;
4050 struct sk_security_struct *osec = other->sk->sk_security;
4051 struct common_audit_data ad;
4052
4053 COMMON_AUDIT_DATA_INIT(&ad, NET);
4054 ad.u.net.sk = other->sk;
4055
4056 return avc_has_perm(ssec->sid, osec->sid, osec->sclass, SOCKET__SENDTO,
4057 &ad);
4058 }
4059
4060 static int selinux_inet_sys_rcv_skb(int ifindex, char *addrp, u16 family,
4061 u32 peer_sid,
4062 struct common_audit_data *ad)
4063 {
4064 int err;
4065 u32 if_sid;
4066 u32 node_sid;
4067
4068 err = sel_netif_sid(ifindex, &if_sid);
4069 if (err)
4070 return err;
4071 err = avc_has_perm(peer_sid, if_sid,
4072 SECCLASS_NETIF, NETIF__INGRESS, ad);
4073 if (err)
4074 return err;
4075
4076 err = sel_netnode_sid(addrp, family, &node_sid);
4077 if (err)
4078 return err;
4079 return avc_has_perm(peer_sid, node_sid,
4080 SECCLASS_NODE, NODE__RECVFROM, ad);
4081 }
4082
4083 static int selinux_sock_rcv_skb_compat(struct sock *sk, struct sk_buff *skb,
4084 u16 family)
4085 {
4086 int err = 0;
4087 struct sk_security_struct *sksec = sk->sk_security;
4088 u32 sk_sid = sksec->sid;
4089 struct common_audit_data ad;
4090 char *addrp;
4091
4092 COMMON_AUDIT_DATA_INIT(&ad, NET);
4093 ad.u.net.netif = skb->skb_iif;
4094 ad.u.net.family = family;
4095 err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL);
4096 if (err)
4097 return err;
4098
4099 if (selinux_secmark_enabled()) {
4100 err = avc_has_perm(sk_sid, skb->secmark, SECCLASS_PACKET,
4101 PACKET__RECV, &ad);
4102 if (err)
4103 return err;
4104 }
4105
4106 err = selinux_netlbl_sock_rcv_skb(sksec, skb, family, &ad);
4107 if (err)
4108 return err;
4109 err = selinux_xfrm_sock_rcv_skb(sksec->sid, skb, &ad);
4110
4111 return err;
4112 }
4113
4114 static int selinux_socket_sock_rcv_skb(struct sock *sk, struct sk_buff *skb)
4115 {
4116 int err;
4117 struct sk_security_struct *sksec = sk->sk_security;
4118 u16 family = sk->sk_family;
4119 u32 sk_sid = sksec->sid;
4120 struct common_audit_data ad;
4121 char *addrp;
4122 u8 secmark_active;
4123 u8 peerlbl_active;
4124
4125 if (family != PF_INET && family != PF_INET6)
4126 return 0;
4127
4128 /* Handle mapped IPv4 packets arriving via IPv6 sockets */
4129 if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
4130 family = PF_INET;
4131
4132 /* If any sort of compatibility mode is enabled then handoff processing
4133 * to the selinux_sock_rcv_skb_compat() function to deal with the
4134 * special handling. We do this in an attempt to keep this function
4135 * as fast and as clean as possible. */
4136 if (!selinux_policycap_netpeer)
4137 return selinux_sock_rcv_skb_compat(sk, skb, family);
4138
4139 secmark_active = selinux_secmark_enabled();
4140 peerlbl_active = netlbl_enabled() || selinux_xfrm_enabled();
4141 if (!secmark_active && !peerlbl_active)
4142 return 0;
4143
4144 COMMON_AUDIT_DATA_INIT(&ad, NET);
4145 ad.u.net.netif = skb->skb_iif;
4146 ad.u.net.family = family;
4147 err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL);
4148 if (err)
4149 return err;
4150
4151 if (peerlbl_active) {
4152 u32 peer_sid;
4153
4154 err = selinux_skb_peerlbl_sid(skb, family, &peer_sid);
4155 if (err)
4156 return err;
4157 err = selinux_inet_sys_rcv_skb(skb->skb_iif, addrp, family,
4158 peer_sid, &ad);
4159 if (err) {
4160 selinux_netlbl_err(skb, err, 0);
4161 return err;
4162 }
4163 err = avc_has_perm(sk_sid, peer_sid, SECCLASS_PEER,
4164 PEER__RECV, &ad);
4165 if (err)
4166 selinux_netlbl_err(skb, err, 0);
4167 }
4168
4169 if (secmark_active) {
4170 err = avc_has_perm(sk_sid, skb->secmark, SECCLASS_PACKET,
4171 PACKET__RECV, &ad);
4172 if (err)
4173 return err;
4174 }
4175
4176 return err;
4177 }
4178
4179 static int selinux_socket_getpeersec_stream(struct socket *sock, char __user *optval,
4180 int __user *optlen, unsigned len)
4181 {
4182 int err = 0;
4183 char *scontext;
4184 u32 scontext_len;
4185 struct sk_security_struct *sksec = sock->sk->sk_security;
4186 u32 peer_sid = SECSID_NULL;
4187
4188 if (sksec->sclass == SECCLASS_UNIX_STREAM_SOCKET ||
4189 sksec->sclass == SECCLASS_TCP_SOCKET)
4190 peer_sid = sksec->peer_sid;
4191 if (peer_sid == SECSID_NULL)
4192 return -ENOPROTOOPT;
4193
4194 err = security_sid_to_context(peer_sid, &scontext, &scontext_len);
4195 if (err)
4196 return err;
4197
4198 if (scontext_len > len) {
4199 err = -ERANGE;
4200 goto out_len;
4201 }
4202
4203 if (copy_to_user(optval, scontext, scontext_len))
4204 err = -EFAULT;
4205
4206 out_len:
4207 if (put_user(scontext_len, optlen))
4208 err = -EFAULT;
4209 kfree(scontext);
4210 return err;
4211 }
4212
4213 static int selinux_socket_getpeersec_dgram(struct socket *sock, struct sk_buff *skb, u32 *secid)
4214 {
4215 u32 peer_secid = SECSID_NULL;
4216 u16 family;
4217
4218 if (skb && skb->protocol == htons(ETH_P_IP))
4219 family = PF_INET;
4220 else if (skb && skb->protocol == htons(ETH_P_IPV6))
4221 family = PF_INET6;
4222 else if (sock)
4223 family = sock->sk->sk_family;
4224 else
4225 goto out;
4226
4227 if (sock && family == PF_UNIX)
4228 selinux_inode_getsecid(SOCK_INODE(sock), &peer_secid);
4229 else if (skb)
4230 selinux_skb_peerlbl_sid(skb, family, &peer_secid);
4231
4232 out:
4233 *secid = peer_secid;
4234 if (peer_secid == SECSID_NULL)
4235 return -EINVAL;
4236 return 0;
4237 }
4238
4239 static int selinux_sk_alloc_security(struct sock *sk, int family, gfp_t priority)
4240 {
4241 struct sk_security_struct *sksec;
4242
4243 sksec = kzalloc(sizeof(*sksec), priority);
4244 if (!sksec)
4245 return -ENOMEM;
4246
4247 sksec->peer_sid = SECINITSID_UNLABELED;
4248 sksec->sid = SECINITSID_UNLABELED;
4249 selinux_netlbl_sk_security_reset(sksec);
4250 sk->sk_security = sksec;
4251
4252 return 0;
4253 }
4254
4255 static void selinux_sk_free_security(struct sock *sk)
4256 {
4257 struct sk_security_struct *sksec = sk->sk_security;
4258
4259 sk->sk_security = NULL;
4260 selinux_netlbl_sk_security_free(sksec);
4261 kfree(sksec);
4262 }
4263
4264 static void selinux_sk_clone_security(const struct sock *sk, struct sock *newsk)
4265 {
4266 struct sk_security_struct *sksec = sk->sk_security;
4267 struct sk_security_struct *newsksec = newsk->sk_security;
4268
4269 newsksec->sid = sksec->sid;
4270 newsksec->peer_sid = sksec->peer_sid;
4271 newsksec->sclass = sksec->sclass;
4272
4273 selinux_netlbl_sk_security_reset(newsksec);
4274 }
4275
4276 static void selinux_sk_getsecid(struct sock *sk, u32 *secid)
4277 {
4278 if (!sk)
4279 *secid = SECINITSID_ANY_SOCKET;
4280 else {
4281 struct sk_security_struct *sksec = sk->sk_security;
4282
4283 *secid = sksec->sid;
4284 }
4285 }
4286
4287 static void selinux_sock_graft(struct sock *sk, struct socket *parent)
4288 {
4289 struct inode_security_struct *isec = SOCK_INODE(parent)->i_security;
4290 struct sk_security_struct *sksec = sk->sk_security;
4291
4292 if (sk->sk_family == PF_INET || sk->sk_family == PF_INET6 ||
4293 sk->sk_family == PF_UNIX)
4294 isec->sid = sksec->sid;
4295 sksec->sclass = isec->sclass;
4296 }
4297
4298 static int selinux_inet_conn_request(struct sock *sk, struct sk_buff *skb,
4299 struct request_sock *req)
4300 {
4301 struct sk_security_struct *sksec = sk->sk_security;
4302 int err;
4303 u16 family = sk->sk_family;
4304 u32 newsid;
4305 u32 peersid;
4306
4307 /* handle mapped IPv4 packets arriving via IPv6 sockets */
4308 if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
4309 family = PF_INET;
4310
4311 err = selinux_skb_peerlbl_sid(skb, family, &peersid);
4312 if (err)
4313 return err;
4314 if (peersid == SECSID_NULL) {
4315 req->secid = sksec->sid;
4316 req->peer_secid = SECSID_NULL;
4317 } else {
4318 err = security_sid_mls_copy(sksec->sid, peersid, &newsid);
4319 if (err)
4320 return err;
4321 req->secid = newsid;
4322 req->peer_secid = peersid;
4323 }
4324
4325 return selinux_netlbl_inet_conn_request(req, family);
4326 }
4327
4328 static void selinux_inet_csk_clone(struct sock *newsk,
4329 const struct request_sock *req)
4330 {
4331 struct sk_security_struct *newsksec = newsk->sk_security;
4332
4333 newsksec->sid = req->secid;
4334 newsksec->peer_sid = req->peer_secid;
4335 /* NOTE: Ideally, we should also get the isec->sid for the
4336 new socket in sync, but we don't have the isec available yet.
4337 So we will wait until sock_graft to do it, by which
4338 time it will have been created and available. */
4339
4340 /* We don't need to take any sort of lock here as we are the only
4341 * thread with access to newsksec */
4342 selinux_netlbl_inet_csk_clone(newsk, req->rsk_ops->family);
4343 }
4344
4345 static void selinux_inet_conn_established(struct sock *sk, struct sk_buff *skb)
4346 {
4347 u16 family = sk->sk_family;
4348 struct sk_security_struct *sksec = sk->sk_security;
4349
4350 /* handle mapped IPv4 packets arriving via IPv6 sockets */
4351 if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
4352 family = PF_INET;
4353
4354 selinux_skb_peerlbl_sid(skb, family, &sksec->peer_sid);
4355 }
4356
4357 static int selinux_secmark_relabel_packet(u32 sid)
4358 {
4359 const struct task_security_struct *__tsec;
4360 u32 tsid;
4361
4362 __tsec = current_security();
4363 tsid = __tsec->sid;
4364
4365 return avc_has_perm(tsid, sid, SECCLASS_PACKET, PACKET__RELABELTO, NULL);
4366 }
4367
4368 static void selinux_secmark_refcount_inc(void)
4369 {
4370 atomic_inc(&selinux_secmark_refcount);
4371 }
4372
4373 static void selinux_secmark_refcount_dec(void)
4374 {
4375 atomic_dec(&selinux_secmark_refcount);
4376 }
4377
4378 static void selinux_req_classify_flow(const struct request_sock *req,
4379 struct flowi *fl)
4380 {
4381 fl->flowi_secid = req->secid;
4382 }
4383
4384 static int selinux_tun_dev_create(void)
4385 {
4386 u32 sid = current_sid();
4387
4388 /* we aren't taking into account the "sockcreate" SID since the socket
4389 * that is being created here is not a socket in the traditional sense,
4390 * instead it is a private sock, accessible only to the kernel, and
4391 * representing a wide range of network traffic spanning multiple
4392 * connections unlike traditional sockets - check the TUN driver to
4393 * get a better understanding of why this socket is special */
4394
4395 return avc_has_perm(sid, sid, SECCLASS_TUN_SOCKET, TUN_SOCKET__CREATE,
4396 NULL);
4397 }
4398
4399 static void selinux_tun_dev_post_create(struct sock *sk)
4400 {
4401 struct sk_security_struct *sksec = sk->sk_security;
4402
4403 /* we don't currently perform any NetLabel based labeling here and it
4404 * isn't clear that we would want to do so anyway; while we could apply
4405 * labeling without the support of the TUN user the resulting labeled
4406 * traffic from the other end of the connection would almost certainly
4407 * cause confusion to the TUN user that had no idea network labeling
4408 * protocols were being used */
4409
4410 /* see the comments in selinux_tun_dev_create() about why we don't use
4411 * the sockcreate SID here */
4412
4413 sksec->sid = current_sid();
4414 sksec->sclass = SECCLASS_TUN_SOCKET;
4415 }
4416
4417 static int selinux_tun_dev_attach(struct sock *sk)
4418 {
4419 struct sk_security_struct *sksec = sk->sk_security;
4420 u32 sid = current_sid();
4421 int err;
4422
4423 err = avc_has_perm(sid, sksec->sid, SECCLASS_TUN_SOCKET,
4424 TUN_SOCKET__RELABELFROM, NULL);
4425 if (err)
4426 return err;
4427 err = avc_has_perm(sid, sid, SECCLASS_TUN_SOCKET,
4428 TUN_SOCKET__RELABELTO, NULL);
4429 if (err)
4430 return err;
4431
4432 sksec->sid = sid;
4433
4434 return 0;
4435 }
4436
4437 static int selinux_nlmsg_perm(struct sock *sk, struct sk_buff *skb)
4438 {
4439 int err = 0;
4440 u32 perm;
4441 struct nlmsghdr *nlh;
4442 struct sk_security_struct *sksec = sk->sk_security;
4443
4444 if (skb->len < NLMSG_SPACE(0)) {
4445 err = -EINVAL;
4446 goto out;
4447 }
4448 nlh = nlmsg_hdr(skb);
4449
4450 err = selinux_nlmsg_lookup(sksec->sclass, nlh->nlmsg_type, &perm);
4451 if (err) {
4452 if (err == -EINVAL) {
4453 audit_log(current->audit_context, GFP_KERNEL, AUDIT_SELINUX_ERR,
4454 "SELinux: unrecognized netlink message"
4455 " type=%hu for sclass=%hu\n",
4456 nlh->nlmsg_type, sksec->sclass);
4457 if (!selinux_enforcing || security_get_allow_unknown())
4458 err = 0;
4459 }
4460
4461 /* Ignore */
4462 if (err == -ENOENT)
4463 err = 0;
4464 goto out;
4465 }
4466
4467 err = sock_has_perm(current, sk, perm);
4468 out:
4469 return err;
4470 }
4471
4472 #ifdef CONFIG_NETFILTER
4473
4474 static unsigned int selinux_ip_forward(struct sk_buff *skb, int ifindex,
4475 u16 family)
4476 {
4477 int err;
4478 char *addrp;
4479 u32 peer_sid;
4480 struct common_audit_data ad;
4481 u8 secmark_active;
4482 u8 netlbl_active;
4483 u8 peerlbl_active;
4484
4485 if (!selinux_policycap_netpeer)
4486 return NF_ACCEPT;
4487
4488 secmark_active = selinux_secmark_enabled();
4489 netlbl_active = netlbl_enabled();
4490 peerlbl_active = netlbl_active || selinux_xfrm_enabled();
4491 if (!secmark_active && !peerlbl_active)
4492 return NF_ACCEPT;
4493
4494 if (selinux_skb_peerlbl_sid(skb, family, &peer_sid) != 0)
4495 return NF_DROP;
4496
4497 COMMON_AUDIT_DATA_INIT(&ad, NET);
4498 ad.u.net.netif = ifindex;
4499 ad.u.net.family = family;
4500 if (selinux_parse_skb(skb, &ad, &addrp, 1, NULL) != 0)
4501 return NF_DROP;
4502
4503 if (peerlbl_active) {
4504 err = selinux_inet_sys_rcv_skb(ifindex, addrp, family,
4505 peer_sid, &ad);
4506 if (err) {
4507 selinux_netlbl_err(skb, err, 1);
4508 return NF_DROP;
4509 }
4510 }
4511
4512 if (secmark_active)
4513 if (avc_has_perm(peer_sid, skb->secmark,
4514 SECCLASS_PACKET, PACKET__FORWARD_IN, &ad))
4515 return NF_DROP;
4516
4517 if (netlbl_active)
4518 /* we do this in the FORWARD path and not the POST_ROUTING
4519 * path because we want to make sure we apply the necessary
4520 * labeling before IPsec is applied so we can leverage AH
4521 * protection */
4522 if (selinux_netlbl_skbuff_setsid(skb, family, peer_sid) != 0)
4523 return NF_DROP;
4524
4525 return NF_ACCEPT;
4526 }
4527
4528 static unsigned int selinux_ipv4_forward(unsigned int hooknum,
4529 struct sk_buff *skb,
4530 const struct net_device *in,
4531 const struct net_device *out,
4532 int (*okfn)(struct sk_buff *))
4533 {
4534 return selinux_ip_forward(skb, in->ifindex, PF_INET);
4535 }
4536
4537 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
4538 static unsigned int selinux_ipv6_forward(unsigned int hooknum,
4539 struct sk_buff *skb,
4540 const struct net_device *in,
4541 const struct net_device *out,
4542 int (*okfn)(struct sk_buff *))
4543 {
4544 return selinux_ip_forward(skb, in->ifindex, PF_INET6);
4545 }
4546 #endif /* IPV6 */
4547
4548 static unsigned int selinux_ip_output(struct sk_buff *skb,
4549 u16 family)
4550 {
4551 u32 sid;
4552
4553 if (!netlbl_enabled())
4554 return NF_ACCEPT;
4555
4556 /* we do this in the LOCAL_OUT path and not the POST_ROUTING path
4557 * because we want to make sure we apply the necessary labeling
4558 * before IPsec is applied so we can leverage AH protection */
4559 if (skb->sk) {
4560 struct sk_security_struct *sksec = skb->sk->sk_security;
4561 sid = sksec->sid;
4562 } else
4563 sid = SECINITSID_KERNEL;
4564 if (selinux_netlbl_skbuff_setsid(skb, family, sid) != 0)
4565 return NF_DROP;
4566
4567 return NF_ACCEPT;
4568 }
4569
4570 static unsigned int selinux_ipv4_output(unsigned int hooknum,
4571 struct sk_buff *skb,
4572 const struct net_device *in,
4573 const struct net_device *out,
4574 int (*okfn)(struct sk_buff *))
4575 {
4576 return selinux_ip_output(skb, PF_INET);
4577 }
4578
4579 static unsigned int selinux_ip_postroute_compat(struct sk_buff *skb,
4580 int ifindex,
4581 u16 family)
4582 {
4583 struct sock *sk = skb->sk;
4584 struct sk_security_struct *sksec;
4585 struct common_audit_data ad;
4586 char *addrp;
4587 u8 proto;
4588
4589 if (sk == NULL)
4590 return NF_ACCEPT;
4591 sksec = sk->sk_security;
4592
4593 COMMON_AUDIT_DATA_INIT(&ad, NET);
4594 ad.u.net.netif = ifindex;
4595 ad.u.net.family = family;
4596 if (selinux_parse_skb(skb, &ad, &addrp, 0, &proto))
4597 return NF_DROP;
4598
4599 if (selinux_secmark_enabled())
4600 if (avc_has_perm(sksec->sid, skb->secmark,
4601 SECCLASS_PACKET, PACKET__SEND, &ad))
4602 return NF_DROP_ERR(-ECONNREFUSED);
4603
4604 if (selinux_xfrm_postroute_last(sksec->sid, skb, &ad, proto))
4605 return NF_DROP_ERR(-ECONNREFUSED);
4606
4607 return NF_ACCEPT;
4608 }
4609
4610 static unsigned int selinux_ip_postroute(struct sk_buff *skb, int ifindex,
4611 u16 family)
4612 {
4613 u32 secmark_perm;
4614 u32 peer_sid;
4615 struct sock *sk;
4616 struct common_audit_data ad;
4617 char *addrp;
4618 u8 secmark_active;
4619 u8 peerlbl_active;
4620
4621 /* If any sort of compatibility mode is enabled then handoff processing
4622 * to the selinux_ip_postroute_compat() function to deal with the
4623 * special handling. We do this in an attempt to keep this function
4624 * as fast and as clean as possible. */
4625 if (!selinux_policycap_netpeer)
4626 return selinux_ip_postroute_compat(skb, ifindex, family);
4627 #ifdef CONFIG_XFRM
4628 /* If skb->dst->xfrm is non-NULL then the packet is undergoing an IPsec
4629 * packet transformation so allow the packet to pass without any checks
4630 * since we'll have another chance to perform access control checks
4631 * when the packet is on it's final way out.
4632 * NOTE: there appear to be some IPv6 multicast cases where skb->dst
4633 * is NULL, in this case go ahead and apply access control. */
4634 if (skb_dst(skb) != NULL && skb_dst(skb)->xfrm != NULL)
4635 return NF_ACCEPT;
4636 #endif
4637 secmark_active = selinux_secmark_enabled();
4638 peerlbl_active = netlbl_enabled() || selinux_xfrm_enabled();
4639 if (!secmark_active && !peerlbl_active)
4640 return NF_ACCEPT;
4641
4642 /* if the packet is being forwarded then get the peer label from the
4643 * packet itself; otherwise check to see if it is from a local
4644 * application or the kernel, if from an application get the peer label
4645 * from the sending socket, otherwise use the kernel's sid */
4646 sk = skb->sk;
4647 if (sk == NULL) {
4648 if (skb->skb_iif) {
4649 secmark_perm = PACKET__FORWARD_OUT;
4650 if (selinux_skb_peerlbl_sid(skb, family, &peer_sid))
4651 return NF_DROP;
4652 } else {
4653 secmark_perm = PACKET__SEND;
4654 peer_sid = SECINITSID_KERNEL;
4655 }
4656 } else {
4657 struct sk_security_struct *sksec = sk->sk_security;
4658 peer_sid = sksec->sid;
4659 secmark_perm = PACKET__SEND;
4660 }
4661
4662 COMMON_AUDIT_DATA_INIT(&ad, NET);
4663 ad.u.net.netif = ifindex;
4664 ad.u.net.family = family;
4665 if (selinux_parse_skb(skb, &ad, &addrp, 0, NULL))
4666 return NF_DROP;
4667
4668 if (secmark_active)
4669 if (avc_has_perm(peer_sid, skb->secmark,
4670 SECCLASS_PACKET, secmark_perm, &ad))
4671 return NF_DROP_ERR(-ECONNREFUSED);
4672
4673 if (peerlbl_active) {
4674 u32 if_sid;
4675 u32 node_sid;
4676
4677 if (sel_netif_sid(ifindex, &if_sid))
4678 return NF_DROP;
4679 if (avc_has_perm(peer_sid, if_sid,
4680 SECCLASS_NETIF, NETIF__EGRESS, &ad))
4681 return NF_DROP_ERR(-ECONNREFUSED);
4682
4683 if (sel_netnode_sid(addrp, family, &node_sid))
4684 return NF_DROP;
4685 if (avc_has_perm(peer_sid, node_sid,
4686 SECCLASS_NODE, NODE__SENDTO, &ad))
4687 return NF_DROP_ERR(-ECONNREFUSED);
4688 }
4689
4690 return NF_ACCEPT;
4691 }
4692
4693 static unsigned int selinux_ipv4_postroute(unsigned int hooknum,
4694 struct sk_buff *skb,
4695 const struct net_device *in,
4696 const struct net_device *out,
4697 int (*okfn)(struct sk_buff *))
4698 {
4699 return selinux_ip_postroute(skb, out->ifindex, PF_INET);
4700 }
4701
4702 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
4703 static unsigned int selinux_ipv6_postroute(unsigned int hooknum,
4704 struct sk_buff *skb,
4705 const struct net_device *in,
4706 const struct net_device *out,
4707 int (*okfn)(struct sk_buff *))
4708 {
4709 return selinux_ip_postroute(skb, out->ifindex, PF_INET6);
4710 }
4711 #endif /* IPV6 */
4712
4713 #endif /* CONFIG_NETFILTER */
4714
4715 static int selinux_netlink_send(struct sock *sk, struct sk_buff *skb)
4716 {
4717 int err;
4718
4719 err = cap_netlink_send(sk, skb);
4720 if (err)
4721 return err;
4722
4723 return selinux_nlmsg_perm(sk, skb);
4724 }
4725
4726 static int selinux_netlink_recv(struct sk_buff *skb, int capability)
4727 {
4728 int err;
4729 struct common_audit_data ad;
4730 u32 sid;
4731
4732 err = cap_netlink_recv(skb, capability);
4733 if (err)
4734 return err;
4735
4736 COMMON_AUDIT_DATA_INIT(&ad, CAP);
4737 ad.u.cap = capability;
4738
4739 security_task_getsecid(current, &sid);
4740 return avc_has_perm(sid, sid, SECCLASS_CAPABILITY,
4741 CAP_TO_MASK(capability), &ad);
4742 }
4743
4744 static int ipc_alloc_security(struct task_struct *task,
4745 struct kern_ipc_perm *perm,
4746 u16 sclass)
4747 {
4748 struct ipc_security_struct *isec;
4749 u32 sid;
4750
4751 isec = kzalloc(sizeof(struct ipc_security_struct), GFP_KERNEL);
4752 if (!isec)
4753 return -ENOMEM;
4754
4755 sid = task_sid(task);
4756 isec->sclass = sclass;
4757 isec->sid = sid;
4758 perm->security = isec;
4759
4760 return 0;
4761 }
4762
4763 static void ipc_free_security(struct kern_ipc_perm *perm)
4764 {
4765 struct ipc_security_struct *isec = perm->security;
4766 perm->security = NULL;
4767 kfree(isec);
4768 }
4769
4770 static int msg_msg_alloc_security(struct msg_msg *msg)
4771 {
4772 struct msg_security_struct *msec;
4773
4774 msec = kzalloc(sizeof(struct msg_security_struct), GFP_KERNEL);
4775 if (!msec)
4776 return -ENOMEM;
4777
4778 msec->sid = SECINITSID_UNLABELED;
4779 msg->security = msec;
4780
4781 return 0;
4782 }
4783
4784 static void msg_msg_free_security(struct msg_msg *msg)
4785 {
4786 struct msg_security_struct *msec = msg->security;
4787
4788 msg->security = NULL;
4789 kfree(msec);
4790 }
4791
4792 static int ipc_has_perm(struct kern_ipc_perm *ipc_perms,
4793 u32 perms)
4794 {
4795 struct ipc_security_struct *isec;
4796 struct common_audit_data ad;
4797 u32 sid = current_sid();
4798
4799 isec = ipc_perms->security;
4800
4801 COMMON_AUDIT_DATA_INIT(&ad, IPC);
4802 ad.u.ipc_id = ipc_perms->key;
4803
4804 return avc_has_perm(sid, isec->sid, isec->sclass, perms, &ad);
4805 }
4806
4807 static int selinux_msg_msg_alloc_security(struct msg_msg *msg)
4808 {
4809 return msg_msg_alloc_security(msg);
4810 }
4811
4812 static void selinux_msg_msg_free_security(struct msg_msg *msg)
4813 {
4814 msg_msg_free_security(msg);
4815 }
4816
4817 /* message queue security operations */
4818 static int selinux_msg_queue_alloc_security(struct msg_queue *msq)
4819 {
4820 struct ipc_security_struct *isec;
4821 struct common_audit_data ad;
4822 u32 sid = current_sid();
4823 int rc;
4824
4825 rc = ipc_alloc_security(current, &msq->q_perm, SECCLASS_MSGQ);
4826 if (rc)
4827 return rc;
4828
4829 isec = msq->q_perm.security;
4830
4831 COMMON_AUDIT_DATA_INIT(&ad, IPC);
4832 ad.u.ipc_id = msq->q_perm.key;
4833
4834 rc = avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
4835 MSGQ__CREATE, &ad);
4836 if (rc) {
4837 ipc_free_security(&msq->q_perm);
4838 return rc;
4839 }
4840 return 0;
4841 }
4842
4843 static void selinux_msg_queue_free_security(struct msg_queue *msq)
4844 {
4845 ipc_free_security(&msq->q_perm);
4846 }
4847
4848 static int selinux_msg_queue_associate(struct msg_queue *msq, int msqflg)
4849 {
4850 struct ipc_security_struct *isec;
4851 struct common_audit_data ad;
4852 u32 sid = current_sid();
4853
4854 isec = msq->q_perm.security;
4855
4856 COMMON_AUDIT_DATA_INIT(&ad, IPC);
4857 ad.u.ipc_id = msq->q_perm.key;
4858
4859 return avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
4860 MSGQ__ASSOCIATE, &ad);
4861 }
4862
4863 static int selinux_msg_queue_msgctl(struct msg_queue *msq, int cmd)
4864 {
4865 int err;
4866 int perms;
4867
4868 switch (cmd) {
4869 case IPC_INFO:
4870 case MSG_INFO:
4871 /* No specific object, just general system-wide information. */
4872 return task_has_system(current, SYSTEM__IPC_INFO);
4873 case IPC_STAT:
4874 case MSG_STAT:
4875 perms = MSGQ__GETATTR | MSGQ__ASSOCIATE;
4876 break;
4877 case IPC_SET:
4878 perms = MSGQ__SETATTR;
4879 break;
4880 case IPC_RMID:
4881 perms = MSGQ__DESTROY;
4882 break;
4883 default:
4884 return 0;
4885 }
4886
4887 err = ipc_has_perm(&msq->q_perm, perms);
4888 return err;
4889 }
4890
4891 static int selinux_msg_queue_msgsnd(struct msg_queue *msq, struct msg_msg *msg, int msqflg)
4892 {
4893 struct ipc_security_struct *isec;
4894 struct msg_security_struct *msec;
4895 struct common_audit_data ad;
4896 u32 sid = current_sid();
4897 int rc;
4898
4899 isec = msq->q_perm.security;
4900 msec = msg->security;
4901
4902 /*
4903 * First time through, need to assign label to the message
4904 */
4905 if (msec->sid == SECINITSID_UNLABELED) {
4906 /*
4907 * Compute new sid based on current process and
4908 * message queue this message will be stored in
4909 */
4910 rc = security_transition_sid(sid, isec->sid, SECCLASS_MSG,
4911 NULL, &msec->sid);
4912 if (rc)
4913 return rc;
4914 }
4915
4916 COMMON_AUDIT_DATA_INIT(&ad, IPC);
4917 ad.u.ipc_id = msq->q_perm.key;
4918
4919 /* Can this process write to the queue? */
4920 rc = avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
4921 MSGQ__WRITE, &ad);
4922 if (!rc)
4923 /* Can this process send the message */
4924 rc = avc_has_perm(sid, msec->sid, SECCLASS_MSG,
4925 MSG__SEND, &ad);
4926 if (!rc)
4927 /* Can the message be put in the queue? */
4928 rc = avc_has_perm(msec->sid, isec->sid, SECCLASS_MSGQ,
4929 MSGQ__ENQUEUE, &ad);
4930
4931 return rc;
4932 }
4933
4934 static int selinux_msg_queue_msgrcv(struct msg_queue *msq, struct msg_msg *msg,
4935 struct task_struct *target,
4936 long type, int mode)
4937 {
4938 struct ipc_security_struct *isec;
4939 struct msg_security_struct *msec;
4940 struct common_audit_data ad;
4941 u32 sid = task_sid(target);
4942 int rc;
4943
4944 isec = msq->q_perm.security;
4945 msec = msg->security;
4946
4947 COMMON_AUDIT_DATA_INIT(&ad, IPC);
4948 ad.u.ipc_id = msq->q_perm.key;
4949
4950 rc = avc_has_perm(sid, isec->sid,
4951 SECCLASS_MSGQ, MSGQ__READ, &ad);
4952 if (!rc)
4953 rc = avc_has_perm(sid, msec->sid,
4954 SECCLASS_MSG, MSG__RECEIVE, &ad);
4955 return rc;
4956 }
4957
4958 /* Shared Memory security operations */
4959 static int selinux_shm_alloc_security(struct shmid_kernel *shp)
4960 {
4961 struct ipc_security_struct *isec;
4962 struct common_audit_data ad;
4963 u32 sid = current_sid();
4964 int rc;
4965
4966 rc = ipc_alloc_security(current, &shp->shm_perm, SECCLASS_SHM);
4967 if (rc)
4968 return rc;
4969
4970 isec = shp->shm_perm.security;
4971
4972 COMMON_AUDIT_DATA_INIT(&ad, IPC);
4973 ad.u.ipc_id = shp->shm_perm.key;
4974
4975 rc = avc_has_perm(sid, isec->sid, SECCLASS_SHM,
4976 SHM__CREATE, &ad);
4977 if (rc) {
4978 ipc_free_security(&shp->shm_perm);
4979 return rc;
4980 }
4981 return 0;
4982 }
4983
4984 static void selinux_shm_free_security(struct shmid_kernel *shp)
4985 {
4986 ipc_free_security(&shp->shm_perm);
4987 }
4988
4989 static int selinux_shm_associate(struct shmid_kernel *shp, int shmflg)
4990 {
4991 struct ipc_security_struct *isec;
4992 struct common_audit_data ad;
4993 u32 sid = current_sid();
4994
4995 isec = shp->shm_perm.security;
4996
4997 COMMON_AUDIT_DATA_INIT(&ad, IPC);
4998 ad.u.ipc_id = shp->shm_perm.key;
4999
5000 return avc_has_perm(sid, isec->sid, SECCLASS_SHM,
5001 SHM__ASSOCIATE, &ad);
5002 }
5003
5004 /* Note, at this point, shp is locked down */
5005 static int selinux_shm_shmctl(struct shmid_kernel *shp, int cmd)
5006 {
5007 int perms;
5008 int err;
5009
5010 switch (cmd) {
5011 case IPC_INFO:
5012 case SHM_INFO:
5013 /* No specific object, just general system-wide information. */
5014 return task_has_system(current, SYSTEM__IPC_INFO);
5015 case IPC_STAT:
5016 case SHM_STAT:
5017 perms = SHM__GETATTR | SHM__ASSOCIATE;
5018 break;
5019 case IPC_SET:
5020 perms = SHM__SETATTR;
5021 break;
5022 case SHM_LOCK:
5023 case SHM_UNLOCK:
5024 perms = SHM__LOCK;
5025 break;
5026 case IPC_RMID:
5027 perms = SHM__DESTROY;
5028 break;
5029 default:
5030 return 0;
5031 }
5032
5033 err = ipc_has_perm(&shp->shm_perm, perms);
5034 return err;
5035 }
5036
5037 static int selinux_shm_shmat(struct shmid_kernel *shp,
5038 char __user *shmaddr, int shmflg)
5039 {
5040 u32 perms;
5041
5042 if (shmflg & SHM_RDONLY)
5043 perms = SHM__READ;
5044 else
5045 perms = SHM__READ | SHM__WRITE;
5046
5047 return ipc_has_perm(&shp->shm_perm, perms);
5048 }
5049
5050 /* Semaphore security operations */
5051 static int selinux_sem_alloc_security(struct sem_array *sma)
5052 {
5053 struct ipc_security_struct *isec;
5054 struct common_audit_data ad;
5055 u32 sid = current_sid();
5056 int rc;
5057
5058 rc = ipc_alloc_security(current, &sma->sem_perm, SECCLASS_SEM);
5059 if (rc)
5060 return rc;
5061
5062 isec = sma->sem_perm.security;
5063
5064 COMMON_AUDIT_DATA_INIT(&ad, IPC);
5065 ad.u.ipc_id = sma->sem_perm.key;
5066
5067 rc = avc_has_perm(sid, isec->sid, SECCLASS_SEM,
5068 SEM__CREATE, &ad);
5069 if (rc) {
5070 ipc_free_security(&sma->sem_perm);
5071 return rc;
5072 }
5073 return 0;
5074 }
5075
5076 static void selinux_sem_free_security(struct sem_array *sma)
5077 {
5078 ipc_free_security(&sma->sem_perm);
5079 }
5080
5081 static int selinux_sem_associate(struct sem_array *sma, int semflg)
5082 {
5083 struct ipc_security_struct *isec;
5084 struct common_audit_data ad;
5085 u32 sid = current_sid();
5086
5087 isec = sma->sem_perm.security;
5088
5089 COMMON_AUDIT_DATA_INIT(&ad, IPC);
5090 ad.u.ipc_id = sma->sem_perm.key;
5091
5092 return avc_has_perm(sid, isec->sid, SECCLASS_SEM,
5093 SEM__ASSOCIATE, &ad);
5094 }
5095
5096 /* Note, at this point, sma is locked down */
5097 static int selinux_sem_semctl(struct sem_array *sma, int cmd)
5098 {
5099 int err;
5100 u32 perms;
5101
5102 switch (cmd) {
5103 case IPC_INFO:
5104 case SEM_INFO:
5105 /* No specific object, just general system-wide information. */
5106 return task_has_system(current, SYSTEM__IPC_INFO);
5107 case GETPID:
5108 case GETNCNT:
5109 case GETZCNT:
5110 perms = SEM__GETATTR;
5111 break;
5112 case GETVAL:
5113 case GETALL:
5114 perms = SEM__READ;
5115 break;
5116 case SETVAL:
5117 case SETALL:
5118 perms = SEM__WRITE;
5119 break;
5120 case IPC_RMID:
5121 perms = SEM__DESTROY;
5122 break;
5123 case IPC_SET:
5124 perms = SEM__SETATTR;
5125 break;
5126 case IPC_STAT:
5127 case SEM_STAT:
5128 perms = SEM__GETATTR | SEM__ASSOCIATE;
5129 break;
5130 default:
5131 return 0;
5132 }
5133
5134 err = ipc_has_perm(&sma->sem_perm, perms);
5135 return err;
5136 }
5137
5138 static int selinux_sem_semop(struct sem_array *sma,
5139 struct sembuf *sops, unsigned nsops, int alter)
5140 {
5141 u32 perms;
5142
5143 if (alter)
5144 perms = SEM__READ | SEM__WRITE;
5145 else
5146 perms = SEM__READ;
5147
5148 return ipc_has_perm(&sma->sem_perm, perms);
5149 }
5150
5151 static int selinux_ipc_permission(struct kern_ipc_perm *ipcp, short flag)
5152 {
5153 u32 av = 0;
5154
5155 av = 0;
5156 if (flag & S_IRUGO)
5157 av |= IPC__UNIX_READ;
5158 if (flag & S_IWUGO)
5159 av |= IPC__UNIX_WRITE;
5160
5161 if (av == 0)
5162 return 0;
5163
5164 return ipc_has_perm(ipcp, av);
5165 }
5166
5167 static void selinux_ipc_getsecid(struct kern_ipc_perm *ipcp, u32 *secid)
5168 {
5169 struct ipc_security_struct *isec = ipcp->security;
5170 *secid = isec->sid;
5171 }
5172
5173 static void selinux_d_instantiate(struct dentry *dentry, struct inode *inode)
5174 {
5175 if (inode)
5176 inode_doinit_with_dentry(inode, dentry);
5177 }
5178
5179 static int selinux_getprocattr(struct task_struct *p,
5180 char *name, char **value)
5181 {
5182 const struct task_security_struct *__tsec;
5183 u32 sid;
5184 int error;
5185 unsigned len;
5186
5187 if (current != p) {
5188 error = current_has_perm(p, PROCESS__GETATTR);
5189 if (error)
5190 return error;
5191 }
5192
5193 rcu_read_lock();
5194 __tsec = __task_cred(p)->security;
5195
5196 if (!strcmp(name, "current"))
5197 sid = __tsec->sid;
5198 else if (!strcmp(name, "prev"))
5199 sid = __tsec->osid;
5200 else if (!strcmp(name, "exec"))
5201 sid = __tsec->exec_sid;
5202 else if (!strcmp(name, "fscreate"))
5203 sid = __tsec->create_sid;
5204 else if (!strcmp(name, "keycreate"))
5205 sid = __tsec->keycreate_sid;
5206 else if (!strcmp(name, "sockcreate"))
5207 sid = __tsec->sockcreate_sid;
5208 else
5209 goto invalid;
5210 rcu_read_unlock();
5211
5212 if (!sid)
5213 return 0;
5214
5215 error = security_sid_to_context(sid, value, &len);
5216 if (error)
5217 return error;
5218 return len;
5219
5220 invalid:
5221 rcu_read_unlock();
5222 return -EINVAL;
5223 }
5224
5225 static int selinux_setprocattr(struct task_struct *p,
5226 char *name, void *value, size_t size)
5227 {
5228 struct task_security_struct *tsec;
5229 struct task_struct *tracer;
5230 struct cred *new;
5231 u32 sid = 0, ptsid;
5232 int error;
5233 char *str = value;
5234
5235 if (current != p) {
5236 /* SELinux only allows a process to change its own
5237 security attributes. */
5238 return -EACCES;
5239 }
5240
5241 /*
5242 * Basic control over ability to set these attributes at all.
5243 * current == p, but we'll pass them separately in case the
5244 * above restriction is ever removed.
5245 */
5246 if (!strcmp(name, "exec"))
5247 error = current_has_perm(p, PROCESS__SETEXEC);
5248 else if (!strcmp(name, "fscreate"))
5249 error = current_has_perm(p, PROCESS__SETFSCREATE);
5250 else if (!strcmp(name, "keycreate"))
5251 error = current_has_perm(p, PROCESS__SETKEYCREATE);
5252 else if (!strcmp(name, "sockcreate"))
5253 error = current_has_perm(p, PROCESS__SETSOCKCREATE);
5254 else if (!strcmp(name, "current"))
5255 error = current_has_perm(p, PROCESS__SETCURRENT);
5256 else
5257 error = -EINVAL;
5258 if (error)
5259 return error;
5260
5261 /* Obtain a SID for the context, if one was specified. */
5262 if (size && str[1] && str[1] != '\n') {
5263 if (str[size-1] == '\n') {
5264 str[size-1] = 0;
5265 size--;
5266 }
5267 error = security_context_to_sid(value, size, &sid);
5268 if (error == -EINVAL && !strcmp(name, "fscreate")) {
5269 if (!capable(CAP_MAC_ADMIN))
5270 return error;
5271 error = security_context_to_sid_force(value, size,
5272 &sid);
5273 }
5274 if (error)
5275 return error;
5276 }
5277
5278 new = prepare_creds();
5279 if (!new)
5280 return -ENOMEM;
5281
5282 /* Permission checking based on the specified context is
5283 performed during the actual operation (execve,
5284 open/mkdir/...), when we know the full context of the
5285 operation. See selinux_bprm_set_creds for the execve
5286 checks and may_create for the file creation checks. The
5287 operation will then fail if the context is not permitted. */
5288 tsec = new->security;
5289 if (!strcmp(name, "exec")) {
5290 tsec->exec_sid = sid;
5291 } else if (!strcmp(name, "fscreate")) {
5292 tsec->create_sid = sid;
5293 } else if (!strcmp(name, "keycreate")) {
5294 error = may_create_key(sid, p);
5295 if (error)
5296 goto abort_change;
5297 tsec->keycreate_sid = sid;
5298 } else if (!strcmp(name, "sockcreate")) {
5299 tsec->sockcreate_sid = sid;
5300 } else if (!strcmp(name, "current")) {
5301 error = -EINVAL;
5302 if (sid == 0)
5303 goto abort_change;
5304
5305 /* Only allow single threaded processes to change context */
5306 error = -EPERM;
5307 if (!current_is_single_threaded()) {
5308 error = security_bounded_transition(tsec->sid, sid);
5309 if (error)
5310 goto abort_change;
5311 }
5312
5313 /* Check permissions for the transition. */
5314 error = avc_has_perm(tsec->sid, sid, SECCLASS_PROCESS,
5315 PROCESS__DYNTRANSITION, NULL);
5316 if (error)
5317 goto abort_change;
5318
5319 /* Check for ptracing, and update the task SID if ok.
5320 Otherwise, leave SID unchanged and fail. */
5321 ptsid = 0;
5322 task_lock(p);
5323 tracer = ptrace_parent(p);
5324 if (tracer)
5325 ptsid = task_sid(tracer);
5326 task_unlock(p);
5327
5328 if (tracer) {
5329 error = avc_has_perm(ptsid, sid, SECCLASS_PROCESS,
5330 PROCESS__PTRACE, NULL);
5331 if (error)
5332 goto abort_change;
5333 }
5334
5335 tsec->sid = sid;
5336 } else {
5337 error = -EINVAL;
5338 goto abort_change;
5339 }
5340
5341 commit_creds(new);
5342 return size;
5343
5344 abort_change:
5345 abort_creds(new);
5346 return error;
5347 }
5348
5349 static int selinux_secid_to_secctx(u32 secid, char **secdata, u32 *seclen)
5350 {
5351 return security_sid_to_context(secid, secdata, seclen);
5352 }
5353
5354 static int selinux_secctx_to_secid(const char *secdata, u32 seclen, u32 *secid)
5355 {
5356 return security_context_to_sid(secdata, seclen, secid);
5357 }
5358
5359 static void selinux_release_secctx(char *secdata, u32 seclen)
5360 {
5361 kfree(secdata);
5362 }
5363
5364 /*
5365 * called with inode->i_mutex locked
5366 */
5367 static int selinux_inode_notifysecctx(struct inode *inode, void *ctx, u32 ctxlen)
5368 {
5369 return selinux_inode_setsecurity(inode, XATTR_SELINUX_SUFFIX, ctx, ctxlen, 0);
5370 }
5371
5372 /*
5373 * called with inode->i_mutex locked
5374 */
5375 static int selinux_inode_setsecctx(struct dentry *dentry, void *ctx, u32 ctxlen)
5376 {
5377 return __vfs_setxattr_noperm(dentry, XATTR_NAME_SELINUX, ctx, ctxlen, 0);
5378 }
5379
5380 static int selinux_inode_getsecctx(struct inode *inode, void **ctx, u32 *ctxlen)
5381 {
5382 int len = 0;
5383 len = selinux_inode_getsecurity(inode, XATTR_SELINUX_SUFFIX,
5384 ctx, true);
5385 if (len < 0)
5386 return len;
5387 *ctxlen = len;
5388 return 0;
5389 }
5390 #ifdef CONFIG_KEYS
5391
5392 static int selinux_key_alloc(struct key *k, const struct cred *cred,
5393 unsigned long flags)
5394 {
5395 const struct task_security_struct *tsec;
5396 struct key_security_struct *ksec;
5397
5398 ksec = kzalloc(sizeof(struct key_security_struct), GFP_KERNEL);
5399 if (!ksec)
5400 return -ENOMEM;
5401
5402 tsec = cred->security;
5403 if (tsec->keycreate_sid)
5404 ksec->sid = tsec->keycreate_sid;
5405 else
5406 ksec->sid = tsec->sid;
5407
5408 k->security = ksec;
5409 return 0;
5410 }
5411
5412 static void selinux_key_free(struct key *k)
5413 {
5414 struct key_security_struct *ksec = k->security;
5415
5416 k->security = NULL;
5417 kfree(ksec);
5418 }
5419
5420 static int selinux_key_permission(key_ref_t key_ref,
5421 const struct cred *cred,
5422 key_perm_t perm)
5423 {
5424 struct key *key;
5425 struct key_security_struct *ksec;
5426 u32 sid;
5427
5428 /* if no specific permissions are requested, we skip the
5429 permission check. No serious, additional covert channels
5430 appear to be created. */
5431 if (perm == 0)
5432 return 0;
5433
5434 sid = cred_sid(cred);
5435
5436 key = key_ref_to_ptr(key_ref);
5437 ksec = key->security;
5438
5439 return avc_has_perm(sid, ksec->sid, SECCLASS_KEY, perm, NULL);
5440 }
5441
5442 static int selinux_key_getsecurity(struct key *key, char **_buffer)
5443 {
5444 struct key_security_struct *ksec = key->security;
5445 char *context = NULL;
5446 unsigned len;
5447 int rc;
5448
5449 rc = security_sid_to_context(ksec->sid, &context, &len);
5450 if (!rc)
5451 rc = len;
5452 *_buffer = context;
5453 return rc;
5454 }
5455
5456 #endif
5457
5458 static struct security_operations selinux_ops = {
5459 .name = "selinux",
5460
5461 .ptrace_access_check = selinux_ptrace_access_check,
5462 .ptrace_traceme = selinux_ptrace_traceme,
5463 .capget = selinux_capget,
5464 .capset = selinux_capset,
5465 .capable = selinux_capable,
5466 .quotactl = selinux_quotactl,
5467 .quota_on = selinux_quota_on,
5468 .syslog = selinux_syslog,
5469 .vm_enough_memory = selinux_vm_enough_memory,
5470
5471 .netlink_send = selinux_netlink_send,
5472 .netlink_recv = selinux_netlink_recv,
5473
5474 .bprm_set_creds = selinux_bprm_set_creds,
5475 .bprm_committing_creds = selinux_bprm_committing_creds,
5476 .bprm_committed_creds = selinux_bprm_committed_creds,
5477 .bprm_secureexec = selinux_bprm_secureexec,
5478
5479 .sb_alloc_security = selinux_sb_alloc_security,
5480 .sb_free_security = selinux_sb_free_security,
5481 .sb_copy_data = selinux_sb_copy_data,
5482 .sb_remount = selinux_sb_remount,
5483 .sb_kern_mount = selinux_sb_kern_mount,
5484 .sb_show_options = selinux_sb_show_options,
5485 .sb_statfs = selinux_sb_statfs,
5486 .sb_mount = selinux_mount,
5487 .sb_umount = selinux_umount,
5488 .sb_set_mnt_opts = selinux_set_mnt_opts,
5489 .sb_clone_mnt_opts = selinux_sb_clone_mnt_opts,
5490 .sb_parse_opts_str = selinux_parse_opts_str,
5491
5492
5493 .inode_alloc_security = selinux_inode_alloc_security,
5494 .inode_free_security = selinux_inode_free_security,
5495 .inode_init_security = selinux_inode_init_security,
5496 .inode_create = selinux_inode_create,
5497 .inode_link = selinux_inode_link,
5498 .inode_unlink = selinux_inode_unlink,
5499 .inode_symlink = selinux_inode_symlink,
5500 .inode_mkdir = selinux_inode_mkdir,
5501 .inode_rmdir = selinux_inode_rmdir,
5502 .inode_mknod = selinux_inode_mknod,
5503 .inode_rename = selinux_inode_rename,
5504 .inode_readlink = selinux_inode_readlink,
5505 .inode_follow_link = selinux_inode_follow_link,
5506 .inode_permission = selinux_inode_permission,
5507 .inode_setattr = selinux_inode_setattr,
5508 .inode_getattr = selinux_inode_getattr,
5509 .inode_setxattr = selinux_inode_setxattr,
5510 .inode_post_setxattr = selinux_inode_post_setxattr,
5511 .inode_getxattr = selinux_inode_getxattr,
5512 .inode_listxattr = selinux_inode_listxattr,
5513 .inode_removexattr = selinux_inode_removexattr,
5514 .inode_getsecurity = selinux_inode_getsecurity,
5515 .inode_setsecurity = selinux_inode_setsecurity,
5516 .inode_listsecurity = selinux_inode_listsecurity,
5517 .inode_getsecid = selinux_inode_getsecid,
5518
5519 .file_permission = selinux_file_permission,
5520 .file_alloc_security = selinux_file_alloc_security,
5521 .file_free_security = selinux_file_free_security,
5522 .file_ioctl = selinux_file_ioctl,
5523 .file_mmap = selinux_file_mmap,
5524 .file_mprotect = selinux_file_mprotect,
5525 .file_lock = selinux_file_lock,
5526 .file_fcntl = selinux_file_fcntl,
5527 .file_set_fowner = selinux_file_set_fowner,
5528 .file_send_sigiotask = selinux_file_send_sigiotask,
5529 .file_receive = selinux_file_receive,
5530
5531 .dentry_open = selinux_dentry_open,
5532
5533 .task_create = selinux_task_create,
5534 .cred_alloc_blank = selinux_cred_alloc_blank,
5535 .cred_free = selinux_cred_free,
5536 .cred_prepare = selinux_cred_prepare,
5537 .cred_transfer = selinux_cred_transfer,
5538 .kernel_act_as = selinux_kernel_act_as,
5539 .kernel_create_files_as = selinux_kernel_create_files_as,
5540 .kernel_module_request = selinux_kernel_module_request,
5541 .task_setpgid = selinux_task_setpgid,
5542 .task_getpgid = selinux_task_getpgid,
5543 .task_getsid = selinux_task_getsid,
5544 .task_getsecid = selinux_task_getsecid,
5545 .task_setnice = selinux_task_setnice,
5546 .task_setioprio = selinux_task_setioprio,
5547 .task_getioprio = selinux_task_getioprio,
5548 .task_setrlimit = selinux_task_setrlimit,
5549 .task_setscheduler = selinux_task_setscheduler,
5550 .task_getscheduler = selinux_task_getscheduler,
5551 .task_movememory = selinux_task_movememory,
5552 .task_kill = selinux_task_kill,
5553 .task_wait = selinux_task_wait,
5554 .task_to_inode = selinux_task_to_inode,
5555
5556 .ipc_permission = selinux_ipc_permission,
5557 .ipc_getsecid = selinux_ipc_getsecid,
5558
5559 .msg_msg_alloc_security = selinux_msg_msg_alloc_security,
5560 .msg_msg_free_security = selinux_msg_msg_free_security,
5561
5562 .msg_queue_alloc_security = selinux_msg_queue_alloc_security,
5563 .msg_queue_free_security = selinux_msg_queue_free_security,
5564 .msg_queue_associate = selinux_msg_queue_associate,
5565 .msg_queue_msgctl = selinux_msg_queue_msgctl,
5566 .msg_queue_msgsnd = selinux_msg_queue_msgsnd,
5567 .msg_queue_msgrcv = selinux_msg_queue_msgrcv,
5568
5569 .shm_alloc_security = selinux_shm_alloc_security,
5570 .shm_free_security = selinux_shm_free_security,
5571 .shm_associate = selinux_shm_associate,
5572 .shm_shmctl = selinux_shm_shmctl,
5573 .shm_shmat = selinux_shm_shmat,
5574
5575 .sem_alloc_security = selinux_sem_alloc_security,
5576 .sem_free_security = selinux_sem_free_security,
5577 .sem_associate = selinux_sem_associate,
5578 .sem_semctl = selinux_sem_semctl,
5579 .sem_semop = selinux_sem_semop,
5580
5581 .d_instantiate = selinux_d_instantiate,
5582
5583 .getprocattr = selinux_getprocattr,
5584 .setprocattr = selinux_setprocattr,
5585
5586 .secid_to_secctx = selinux_secid_to_secctx,
5587 .secctx_to_secid = selinux_secctx_to_secid,
5588 .release_secctx = selinux_release_secctx,
5589 .inode_notifysecctx = selinux_inode_notifysecctx,
5590 .inode_setsecctx = selinux_inode_setsecctx,
5591 .inode_getsecctx = selinux_inode_getsecctx,
5592
5593 .unix_stream_connect = selinux_socket_unix_stream_connect,
5594 .unix_may_send = selinux_socket_unix_may_send,
5595
5596 .socket_create = selinux_socket_create,
5597 .socket_post_create = selinux_socket_post_create,
5598 .socket_bind = selinux_socket_bind,
5599 .socket_connect = selinux_socket_connect,
5600 .socket_listen = selinux_socket_listen,
5601 .socket_accept = selinux_socket_accept,
5602 .socket_sendmsg = selinux_socket_sendmsg,
5603 .socket_recvmsg = selinux_socket_recvmsg,
5604 .socket_getsockname = selinux_socket_getsockname,
5605 .socket_getpeername = selinux_socket_getpeername,
5606 .socket_getsockopt = selinux_socket_getsockopt,
5607 .socket_setsockopt = selinux_socket_setsockopt,
5608 .socket_shutdown = selinux_socket_shutdown,
5609 .socket_sock_rcv_skb = selinux_socket_sock_rcv_skb,
5610 .socket_getpeersec_stream = selinux_socket_getpeersec_stream,
5611 .socket_getpeersec_dgram = selinux_socket_getpeersec_dgram,
5612 .sk_alloc_security = selinux_sk_alloc_security,
5613 .sk_free_security = selinux_sk_free_security,
5614 .sk_clone_security = selinux_sk_clone_security,
5615 .sk_getsecid = selinux_sk_getsecid,
5616 .sock_graft = selinux_sock_graft,
5617 .inet_conn_request = selinux_inet_conn_request,
5618 .inet_csk_clone = selinux_inet_csk_clone,
5619 .inet_conn_established = selinux_inet_conn_established,
5620 .secmark_relabel_packet = selinux_secmark_relabel_packet,
5621 .secmark_refcount_inc = selinux_secmark_refcount_inc,
5622 .secmark_refcount_dec = selinux_secmark_refcount_dec,
5623 .req_classify_flow = selinux_req_classify_flow,
5624 .tun_dev_create = selinux_tun_dev_create,
5625 .tun_dev_post_create = selinux_tun_dev_post_create,
5626 .tun_dev_attach = selinux_tun_dev_attach,
5627
5628 #ifdef CONFIG_SECURITY_NETWORK_XFRM
5629 .xfrm_policy_alloc_security = selinux_xfrm_policy_alloc,
5630 .xfrm_policy_clone_security = selinux_xfrm_policy_clone,
5631 .xfrm_policy_free_security = selinux_xfrm_policy_free,
5632 .xfrm_policy_delete_security = selinux_xfrm_policy_delete,
5633 .xfrm_state_alloc_security = selinux_xfrm_state_alloc,
5634 .xfrm_state_free_security = selinux_xfrm_state_free,
5635 .xfrm_state_delete_security = selinux_xfrm_state_delete,
5636 .xfrm_policy_lookup = selinux_xfrm_policy_lookup,
5637 .xfrm_state_pol_flow_match = selinux_xfrm_state_pol_flow_match,
5638 .xfrm_decode_session = selinux_xfrm_decode_session,
5639 #endif
5640
5641 #ifdef CONFIG_KEYS
5642 .key_alloc = selinux_key_alloc,
5643 .key_free = selinux_key_free,
5644 .key_permission = selinux_key_permission,
5645 .key_getsecurity = selinux_key_getsecurity,
5646 #endif
5647
5648 #ifdef CONFIG_AUDIT
5649 .audit_rule_init = selinux_audit_rule_init,
5650 .audit_rule_known = selinux_audit_rule_known,
5651 .audit_rule_match = selinux_audit_rule_match,
5652 .audit_rule_free = selinux_audit_rule_free,
5653 #endif
5654 };
5655
5656 static __init int selinux_init(void)
5657 {
5658 if (!security_module_enable(&selinux_ops)) {
5659 selinux_enabled = 0;
5660 return 0;
5661 }
5662
5663 if (!selinux_enabled) {
5664 printk(KERN_INFO "SELinux: Disabled at boot.\n");
5665 return 0;
5666 }
5667
5668 printk(KERN_INFO "SELinux: Initializing.\n");
5669
5670 /* Set the security state for the initial task. */
5671 cred_init_security();
5672
5673 default_noexec = !(VM_DATA_DEFAULT_FLAGS & VM_EXEC);
5674
5675 sel_inode_cache = kmem_cache_create("selinux_inode_security",
5676 sizeof(struct inode_security_struct),
5677 0, SLAB_PANIC, NULL);
5678 avc_init();
5679
5680 if (register_security(&selinux_ops))
5681 panic("SELinux: Unable to register with kernel.\n");
5682
5683 if (selinux_enforcing)
5684 printk(KERN_DEBUG "SELinux: Starting in enforcing mode\n");
5685 else
5686 printk(KERN_DEBUG "SELinux: Starting in permissive mode\n");
5687
5688 return 0;
5689 }
5690
5691 static void delayed_superblock_init(struct super_block *sb, void *unused)
5692 {
5693 superblock_doinit(sb, NULL);
5694 }
5695
5696 void selinux_complete_init(void)
5697 {
5698 printk(KERN_DEBUG "SELinux: Completing initialization.\n");
5699
5700 /* Set up any superblocks initialized prior to the policy load. */
5701 printk(KERN_DEBUG "SELinux: Setting up existing superblocks.\n");
5702 iterate_supers(delayed_superblock_init, NULL);
5703 }
5704
5705 /* SELinux requires early initialization in order to label
5706 all processes and objects when they are created. */
5707 security_initcall(selinux_init);
5708
5709 #if defined(CONFIG_NETFILTER)
5710
5711 static struct nf_hook_ops selinux_ipv4_ops[] = {
5712 {
5713 .hook = selinux_ipv4_postroute,
5714 .owner = THIS_MODULE,
5715 .pf = PF_INET,
5716 .hooknum = NF_INET_POST_ROUTING,
5717 .priority = NF_IP_PRI_SELINUX_LAST,
5718 },
5719 {
5720 .hook = selinux_ipv4_forward,
5721 .owner = THIS_MODULE,
5722 .pf = PF_INET,
5723 .hooknum = NF_INET_FORWARD,
5724 .priority = NF_IP_PRI_SELINUX_FIRST,
5725 },
5726 {
5727 .hook = selinux_ipv4_output,
5728 .owner = THIS_MODULE,
5729 .pf = PF_INET,
5730 .hooknum = NF_INET_LOCAL_OUT,
5731 .priority = NF_IP_PRI_SELINUX_FIRST,
5732 }
5733 };
5734
5735 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
5736
5737 static struct nf_hook_ops selinux_ipv6_ops[] = {
5738 {
5739 .hook = selinux_ipv6_postroute,
5740 .owner = THIS_MODULE,
5741 .pf = PF_INET6,
5742 .hooknum = NF_INET_POST_ROUTING,
5743 .priority = NF_IP6_PRI_SELINUX_LAST,
5744 },
5745 {
5746 .hook = selinux_ipv6_forward,
5747 .owner = THIS_MODULE,
5748 .pf = PF_INET6,
5749 .hooknum = NF_INET_FORWARD,
5750 .priority = NF_IP6_PRI_SELINUX_FIRST,
5751 }
5752 };
5753
5754 #endif /* IPV6 */
5755
5756 static int __init selinux_nf_ip_init(void)
5757 {
5758 int err = 0;
5759
5760 if (!selinux_enabled)
5761 goto out;
5762
5763 printk(KERN_DEBUG "SELinux: Registering netfilter hooks\n");
5764
5765 err = nf_register_hooks(selinux_ipv4_ops, ARRAY_SIZE(selinux_ipv4_ops));
5766 if (err)
5767 panic("SELinux: nf_register_hooks for IPv4: error %d\n", err);
5768
5769 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
5770 err = nf_register_hooks(selinux_ipv6_ops, ARRAY_SIZE(selinux_ipv6_ops));
5771 if (err)
5772 panic("SELinux: nf_register_hooks for IPv6: error %d\n", err);
5773 #endif /* IPV6 */
5774
5775 out:
5776 return err;
5777 }
5778
5779 __initcall(selinux_nf_ip_init);
5780
5781 #ifdef CONFIG_SECURITY_SELINUX_DISABLE
5782 static void selinux_nf_ip_exit(void)
5783 {
5784 printk(KERN_DEBUG "SELinux: Unregistering netfilter hooks\n");
5785
5786 nf_unregister_hooks(selinux_ipv4_ops, ARRAY_SIZE(selinux_ipv4_ops));
5787 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
5788 nf_unregister_hooks(selinux_ipv6_ops, ARRAY_SIZE(selinux_ipv6_ops));
5789 #endif /* IPV6 */
5790 }
5791 #endif
5792
5793 #else /* CONFIG_NETFILTER */
5794
5795 #ifdef CONFIG_SECURITY_SELINUX_DISABLE
5796 #define selinux_nf_ip_exit()
5797 #endif
5798
5799 #endif /* CONFIG_NETFILTER */
5800
5801 #ifdef CONFIG_SECURITY_SELINUX_DISABLE
5802 static int selinux_disabled;
5803
5804 int selinux_disable(void)
5805 {
5806 extern void exit_sel_fs(void);
5807
5808 if (ss_initialized) {
5809 /* Not permitted after initial policy load. */
5810 return -EINVAL;
5811 }
5812
5813 if (selinux_disabled) {
5814 /* Only do this once. */
5815 return -EINVAL;
5816 }
5817
5818 printk(KERN_INFO "SELinux: Disabled at runtime.\n");
5819
5820 selinux_disabled = 1;
5821 selinux_enabled = 0;
5822
5823 reset_security_ops();
5824
5825 /* Try to destroy the avc node cache */
5826 avc_disable();
5827
5828 /* Unregister netfilter hooks. */
5829 selinux_nf_ip_exit();
5830
5831 /* Unregister selinuxfs. */
5832 exit_sel_fs();
5833
5834 return 0;
5835 }
5836 #endif
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