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