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Added hardlink support
[pohmelfs.git] / security / selinux / hooks.c
blob6a3683e28426b132d5890398609710bca7397310
1 /*
2 * NSA Security-Enhanced Linux (SELinux) security module
3 *
4 * This file contains the SELinux hook function implementations.
5 *
6 * Authors: Stephen Smalley, <sds@epoch.ncsc.mil>
7 * Chris Vance, <cvance@nai.com>
8 * Wayne Salamon, <wsalamon@nai.com>
9 * James Morris <jmorris@redhat.com>
10 *
11 * Copyright (C) 2001,2002 Networks Associates Technology, Inc.
12 * Copyright (C) 2003-2008 Red Hat, Inc., James Morris <jmorris@redhat.com>
13 * Eric Paris <eparis@redhat.com>
14 * Copyright (C) 2004-2005 Trusted Computer Solutions, Inc.
15 * <dgoeddel@trustedcs.com>
16 * Copyright (C) 2006, 2007, 2009 Hewlett-Packard Development Company, L.P.
17 * Paul Moore <paul@paul-moore.com>
18 * Copyright (C) 2007 Hitachi Software Engineering Co., Ltd.
19 * Yuichi Nakamura <ynakam@hitachisoft.jp>
20 *
21 * This program is free software; you can redistribute it and/or modify
22 * it under the terms of the GNU General Public License version 2,
23 * as published by the Free Software Foundation.
24 */
25
26 #include <linux/init.h>
27 #include <linux/kd.h>
28 #include <linux/kernel.h>
29 #include <linux/tracehook.h>
30 #include <linux/errno.h>
31 #include <linux/ext2_fs.h>
32 #include <linux/sched.h>
33 #include <linux/security.h>
34 #include <linux/xattr.h>
35 #include <linux/capability.h>
36 #include <linux/unistd.h>
37 #include <linux/mm.h>
38 #include <linux/mman.h>
39 #include <linux/slab.h>
40 #include <linux/pagemap.h>
41 #include <linux/proc_fs.h>
42 #include <linux/swap.h>
43 #include <linux/spinlock.h>
44 #include <linux/syscalls.h>
45 #include <linux/dcache.h>
46 #include <linux/file.h>
47 #include <linux/fdtable.h>
48 #include <linux/namei.h>
49 #include <linux/mount.h>
50 #include <linux/netfilter_ipv4.h>
51 #include <linux/netfilter_ipv6.h>
52 #include <linux/tty.h>
53 #include <net/icmp.h>
54 #include <net/ip.h> /* for local_port_range[] */
55 #include <net/tcp.h> /* struct or_callable used in sock_rcv_skb */
56 #include <net/net_namespace.h>
57 #include <net/netlabel.h>
58 #include <linux/uaccess.h>
59 #include <asm/ioctls.h>
60 #include <linux/atomic.h>
61 #include <linux/bitops.h>
62 #include <linux/interrupt.h>
63 #include <linux/netdevice.h> /* for network interface checks */
64 #include <linux/netlink.h>
65 #include <linux/tcp.h>
66 #include <linux/udp.h>
67 #include <linux/dccp.h>
68 #include <linux/quota.h>
69 #include <linux/un.h> /* for Unix socket types */
70 #include <net/af_unix.h> /* for Unix socket types */
71 #include <linux/parser.h>
72 #include <linux/nfs_mount.h>
73 #include <net/ipv6.h>
74 #include <linux/hugetlb.h>
75 #include <linux/personality.h>
76 #include <linux/audit.h>
77 #include <linux/string.h>
78 #include <linux/selinux.h>
79 #include <linux/mutex.h>
80 #include <linux/posix-timers.h>
81 #include <linux/syslog.h>
82 #include <linux/user_namespace.h>
83 #include <linux/export.h>
84
85 #include "avc.h"
86 #include "objsec.h"
87 #include "netif.h"
88 #include "netnode.h"
89 #include "netport.h"
90 #include "xfrm.h"
91 #include "netlabel.h"
92 #include "audit.h"
93 #include "avc_ss.h"
94
95 #define NUM_SEL_MNT_OPTS 5
96
97 extern struct security_operations *security_ops;
98
99 /* SECMARK reference count */
100 static atomic_t selinux_secmark_refcount = ATOMIC_INIT(0);
101
102 #ifdef CONFIG_SECURITY_SELINUX_DEVELOP
103 int selinux_enforcing;
104
105 static int __init enforcing_setup(char *str)
106 {
107 unsigned long enforcing;
108 if (!strict_strtoul(str, 0, &enforcing))
109 selinux_enforcing = enforcing ? 1 : 0;
110 return 1;
111 }
112 __setup("enforcing=", enforcing_setup);
113 #endif
114
115 #ifdef CONFIG_SECURITY_SELINUX_BOOTPARAM
116 int selinux_enabled = CONFIG_SECURITY_SELINUX_BOOTPARAM_VALUE;
117
118 static int __init selinux_enabled_setup(char *str)
119 {
120 unsigned long enabled;
121 if (!strict_strtoul(str, 0, &enabled))
122 selinux_enabled = enabled ? 1 : 0;
123 return 1;
124 }
125 __setup("selinux=", selinux_enabled_setup);
126 #else
127 int selinux_enabled = 1;
128 #endif
129
130 static struct kmem_cache *sel_inode_cache;
131
132 /**
133 * selinux_secmark_enabled - Check to see if SECMARK is currently enabled
134 *
135 * Description:
136 * This function checks the SECMARK reference counter to see if any SECMARK
137 * targets are currently configured, if the reference counter is greater than
138 * zero SECMARK is considered to be enabled. Returns true (1) if SECMARK is
139 * enabled, false (0) if SECMARK is disabled.
140 *
141 */
142 static int selinux_secmark_enabled(void)
143 {
144 return (atomic_read(&selinux_secmark_refcount) > 0);
145 }
146
147 /*
148 * initialise the security for the init task
149 */
150 static void cred_init_security(void)
151 {
152 struct cred *cred = (struct cred *) current->real_cred;
153 struct task_security_struct *tsec;
154
155 tsec = kzalloc(sizeof(struct task_security_struct), GFP_KERNEL);
156 if (!tsec)
157 panic("SELinux: Failed to initialize initial task.\n");
158
159 tsec->osid = tsec->sid = SECINITSID_KERNEL;
160 cred->security = tsec;
161 }
162
163 /*
164 * get the security ID of a set of credentials
165 */
166 static inline u32 cred_sid(const struct cred *cred)
167 {
168 const struct task_security_struct *tsec;
169
170 tsec = cred->security;
171 return tsec->sid;
172 }
173
174 /*
175 * get the objective security ID of a task
176 */
177 static inline u32 task_sid(const struct task_struct *task)
178 {
179 u32 sid;
180
181 rcu_read_lock();
182 sid = cred_sid(__task_cred(task));
183 rcu_read_unlock();
184 return sid;
185 }
186
187 /*
188 * get the subjective security ID of the current task
189 */
190 static inline u32 current_sid(void)
191 {
192 const struct task_security_struct *tsec = current_security();
193
194 return tsec->sid;
195 }
196
197 /* Allocate and free functions for each kind of security blob. */
198
199 static int inode_alloc_security(struct inode *inode)
200 {
201 struct inode_security_struct *isec;
202 u32 sid = current_sid();
203
204 isec = kmem_cache_zalloc(sel_inode_cache, GFP_NOFS);
205 if (!isec)
206 return -ENOMEM;
207
208 mutex_init(&isec->lock);
209 INIT_LIST_HEAD(&isec->list);
210 isec->inode = inode;
211 isec->sid = SECINITSID_UNLABELED;
212 isec->sclass = SECCLASS_FILE;
213 isec->task_sid = sid;
214 inode->i_security = isec;
215
216 return 0;
217 }
218
219 static void inode_free_security(struct inode *inode)
220 {
221 struct inode_security_struct *isec = inode->i_security;
222 struct superblock_security_struct *sbsec = inode->i_sb->s_security;
223
224 spin_lock(&sbsec->isec_lock);
225 if (!list_empty(&isec->list))
226 list_del_init(&isec->list);
227 spin_unlock(&sbsec->isec_lock);
228
229 inode->i_security = NULL;
230 kmem_cache_free(sel_inode_cache, isec);
231 }
232
233 static int file_alloc_security(struct file *file)
234 {
235 struct file_security_struct *fsec;
236 u32 sid = current_sid();
237
238 fsec = kzalloc(sizeof(struct file_security_struct), GFP_KERNEL);
239 if (!fsec)
240 return -ENOMEM;
241
242 fsec->sid = sid;
243 fsec->fown_sid = sid;
244 file->f_security = fsec;
245
246 return 0;
247 }
248
249 static void file_free_security(struct file *file)
250 {
251 struct file_security_struct *fsec = file->f_security;
252 file->f_security = NULL;
253 kfree(fsec);
254 }
255
256 static int superblock_alloc_security(struct super_block *sb)
257 {
258 struct superblock_security_struct *sbsec;
259
260 sbsec = kzalloc(sizeof(struct superblock_security_struct), GFP_KERNEL);
261 if (!sbsec)
262 return -ENOMEM;
263
264 mutex_init(&sbsec->lock);
265 INIT_LIST_HEAD(&sbsec->isec_head);
266 spin_lock_init(&sbsec->isec_lock);
267 sbsec->sb = sb;
268 sbsec->sid = SECINITSID_UNLABELED;
269 sbsec->def_sid = SECINITSID_FILE;
270 sbsec->mntpoint_sid = SECINITSID_UNLABELED;
271 sb->s_security = sbsec;
272
273 return 0;
274 }
275
276 static void superblock_free_security(struct super_block *sb)
277 {
278 struct superblock_security_struct *sbsec = sb->s_security;
279 sb->s_security = NULL;
280 kfree(sbsec);
281 }
282
283 /* The file system's label must be initialized prior to use. */
284
285 static const char *labeling_behaviors[6] = {
286 "uses xattr",
287 "uses transition SIDs",
288 "uses task SIDs",
289 "uses genfs_contexts",
290 "not configured for labeling",
291 "uses mountpoint labeling",
292 };
293
294 static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dentry);
295
296 static inline int inode_doinit(struct inode *inode)
297 {
298 return inode_doinit_with_dentry(inode, NULL);
299 }
300
301 enum {
302 Opt_error = -1,
303 Opt_context = 1,
304 Opt_fscontext = 2,
305 Opt_defcontext = 3,
306 Opt_rootcontext = 4,
307 Opt_labelsupport = 5,
308 };
309
310 static const match_table_t tokens = {
311 {Opt_context, CONTEXT_STR "%s"},
312 {Opt_fscontext, FSCONTEXT_STR "%s"},
313 {Opt_defcontext, DEFCONTEXT_STR "%s"},
314 {Opt_rootcontext, ROOTCONTEXT_STR "%s"},
315 {Opt_labelsupport, LABELSUPP_STR},
316 {Opt_error, NULL},
317 };
318
319 #define SEL_MOUNT_FAIL_MSG "SELinux: duplicate or incompatible mount options\n"
320
321 static int may_context_mount_sb_relabel(u32 sid,
322 struct superblock_security_struct *sbsec,
323 const struct cred *cred)
324 {
325 const struct task_security_struct *tsec = cred->security;
326 int rc;
327
328 rc = avc_has_perm(tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM,
329 FILESYSTEM__RELABELFROM, NULL);
330 if (rc)
331 return rc;
332
333 rc = avc_has_perm(tsec->sid, sid, SECCLASS_FILESYSTEM,
334 FILESYSTEM__RELABELTO, NULL);
335 return rc;
336 }
337
338 static int may_context_mount_inode_relabel(u32 sid,
339 struct superblock_security_struct *sbsec,
340 const struct cred *cred)
341 {
342 const struct task_security_struct *tsec = cred->security;
343 int rc;
344 rc = avc_has_perm(tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM,
345 FILESYSTEM__RELABELFROM, NULL);
346 if (rc)
347 return rc;
348
349 rc = avc_has_perm(sid, sbsec->sid, SECCLASS_FILESYSTEM,
350 FILESYSTEM__ASSOCIATE, NULL);
351 return rc;
352 }
353
354 static int sb_finish_set_opts(struct super_block *sb)
355 {
356 struct superblock_security_struct *sbsec = sb->s_security;
357 struct dentry *root = sb->s_root;
358 struct inode *root_inode = root->d_inode;
359 int rc = 0;
360
361 if (sbsec->behavior == SECURITY_FS_USE_XATTR) {
362 /* Make sure that the xattr handler exists and that no
363 error other than -ENODATA is returned by getxattr on
364 the root directory. -ENODATA is ok, as this may be
365 the first boot of the SELinux kernel before we have
366 assigned xattr values to the filesystem. */
367 if (!root_inode->i_op->getxattr) {
368 printk(KERN_WARNING "SELinux: (dev %s, type %s) has no "
369 "xattr support\n", sb->s_id, sb->s_type->name);
370 rc = -EOPNOTSUPP;
371 goto out;
372 }
373 rc = root_inode->i_op->getxattr(root, XATTR_NAME_SELINUX, NULL, 0);
374 if (rc < 0 && rc != -ENODATA) {
375 if (rc == -EOPNOTSUPP)
376 printk(KERN_WARNING "SELinux: (dev %s, type "
377 "%s) has no security xattr handler\n",
378 sb->s_id, sb->s_type->name);
379 else
380 printk(KERN_WARNING "SELinux: (dev %s, type "
381 "%s) getxattr errno %d\n", sb->s_id,
382 sb->s_type->name, -rc);
383 goto out;
384 }
385 }
386
387 sbsec->flags |= (SE_SBINITIALIZED | SE_SBLABELSUPP);
388
389 if (sbsec->behavior > ARRAY_SIZE(labeling_behaviors))
390 printk(KERN_ERR "SELinux: initialized (dev %s, type %s), unknown behavior\n",
391 sb->s_id, sb->s_type->name);
392 else
393 printk(KERN_DEBUG "SELinux: initialized (dev %s, type %s), %s\n",
394 sb->s_id, sb->s_type->name,
395 labeling_behaviors[sbsec->behavior-1]);
396
397 if (sbsec->behavior == SECURITY_FS_USE_GENFS ||
398 sbsec->behavior == SECURITY_FS_USE_MNTPOINT ||
399 sbsec->behavior == SECURITY_FS_USE_NONE ||
400 sbsec->behavior > ARRAY_SIZE(labeling_behaviors))
401 sbsec->flags &= ~SE_SBLABELSUPP;
402
403 /* Special handling for sysfs. Is genfs but also has setxattr handler*/
404 if (strncmp(sb->s_type->name, "sysfs", sizeof("sysfs")) == 0)
405 sbsec->flags |= SE_SBLABELSUPP;
406
407 /* Initialize the root inode. */
408 rc = inode_doinit_with_dentry(root_inode, root);
409
410 /* Initialize any other inodes associated with the superblock, e.g.
411 inodes created prior to initial policy load or inodes created
412 during get_sb by a pseudo filesystem that directly
413 populates itself. */
414 spin_lock(&sbsec->isec_lock);
415 next_inode:
416 if (!list_empty(&sbsec->isec_head)) {
417 struct inode_security_struct *isec =
418 list_entry(sbsec->isec_head.next,
419 struct inode_security_struct, list);
420 struct inode *inode = isec->inode;
421 spin_unlock(&sbsec->isec_lock);
422 inode = igrab(inode);
423 if (inode) {
424 if (!IS_PRIVATE(inode))
425 inode_doinit(inode);
426 iput(inode);
427 }
428 spin_lock(&sbsec->isec_lock);
429 list_del_init(&isec->list);
430 goto next_inode;
431 }
432 spin_unlock(&sbsec->isec_lock);
433 out:
434 return rc;
435 }
436
437 /*
438 * This function should allow an FS to ask what it's mount security
439 * options were so it can use those later for submounts, displaying
440 * mount options, or whatever.
441 */
442 static int selinux_get_mnt_opts(const struct super_block *sb,
443 struct security_mnt_opts *opts)
444 {
445 int rc = 0, i;
446 struct superblock_security_struct *sbsec = sb->s_security;
447 char *context = NULL;
448 u32 len;
449 char tmp;
450
451 security_init_mnt_opts(opts);
452
453 if (!(sbsec->flags & SE_SBINITIALIZED))
454 return -EINVAL;
455
456 if (!ss_initialized)
457 return -EINVAL;
458
459 tmp = sbsec->flags & SE_MNTMASK;
460 /* count the number of mount options for this sb */
461 for (i = 0; i < 8; i++) {
462 if (tmp & 0x01)
463 opts->num_mnt_opts++;
464 tmp >>= 1;
465 }
466 /* Check if the Label support flag is set */
467 if (sbsec->flags & SE_SBLABELSUPP)
468 opts->num_mnt_opts++;
469
470 opts->mnt_opts = kcalloc(opts->num_mnt_opts, sizeof(char *), GFP_ATOMIC);
471 if (!opts->mnt_opts) {
472 rc = -ENOMEM;
473 goto out_free;
474 }
475
476 opts->mnt_opts_flags = kcalloc(opts->num_mnt_opts, sizeof(int), GFP_ATOMIC);
477 if (!opts->mnt_opts_flags) {
478 rc = -ENOMEM;
479 goto out_free;
480 }
481
482 i = 0;
483 if (sbsec->flags & FSCONTEXT_MNT) {
484 rc = security_sid_to_context(sbsec->sid, &context, &len);
485 if (rc)
486 goto out_free;
487 opts->mnt_opts[i] = context;
488 opts->mnt_opts_flags[i++] = FSCONTEXT_MNT;
489 }
490 if (sbsec->flags & CONTEXT_MNT) {
491 rc = security_sid_to_context(sbsec->mntpoint_sid, &context, &len);
492 if (rc)
493 goto out_free;
494 opts->mnt_opts[i] = context;
495 opts->mnt_opts_flags[i++] = CONTEXT_MNT;
496 }
497 if (sbsec->flags & DEFCONTEXT_MNT) {
498 rc = security_sid_to_context(sbsec->def_sid, &context, &len);
499 if (rc)
500 goto out_free;
501 opts->mnt_opts[i] = context;
502 opts->mnt_opts_flags[i++] = DEFCONTEXT_MNT;
503 }
504 if (sbsec->flags & ROOTCONTEXT_MNT) {
505 struct inode *root = sbsec->sb->s_root->d_inode;
506 struct inode_security_struct *isec = root->i_security;
507
508 rc = security_sid_to_context(isec->sid, &context, &len);
509 if (rc)
510 goto out_free;
511 opts->mnt_opts[i] = context;
512 opts->mnt_opts_flags[i++] = ROOTCONTEXT_MNT;
513 }
514 if (sbsec->flags & SE_SBLABELSUPP) {
515 opts->mnt_opts[i] = NULL;
516 opts->mnt_opts_flags[i++] = SE_SBLABELSUPP;
517 }
518
519 BUG_ON(i != opts->num_mnt_opts);
520
521 return 0;
522
523 out_free:
524 security_free_mnt_opts(opts);
525 return rc;
526 }
527
528 static int bad_option(struct superblock_security_struct *sbsec, char flag,
529 u32 old_sid, u32 new_sid)
530 {
531 char mnt_flags = sbsec->flags & SE_MNTMASK;
532
533 /* check if the old mount command had the same options */
534 if (sbsec->flags & SE_SBINITIALIZED)
535 if (!(sbsec->flags & flag) ||
536 (old_sid != new_sid))
537 return 1;
538
539 /* check if we were passed the same options twice,
540 * aka someone passed context=a,context=b
541 */
542 if (!(sbsec->flags & SE_SBINITIALIZED))
543 if (mnt_flags & flag)
544 return 1;
545 return 0;
546 }
547
548 /*
549 * Allow filesystems with binary mount data to explicitly set mount point
550 * labeling information.
551 */
552 static int selinux_set_mnt_opts(struct super_block *sb,
553 struct security_mnt_opts *opts)
554 {
555 const struct cred *cred = current_cred();
556 int rc = 0, i;
557 struct superblock_security_struct *sbsec = sb->s_security;
558 const char *name = sb->s_type->name;
559 struct inode *inode = sbsec->sb->s_root->d_inode;
560 struct inode_security_struct *root_isec = inode->i_security;
561 u32 fscontext_sid = 0, context_sid = 0, rootcontext_sid = 0;
562 u32 defcontext_sid = 0;
563 char **mount_options = opts->mnt_opts;
564 int *flags = opts->mnt_opts_flags;
565 int num_opts = opts->num_mnt_opts;
566
567 mutex_lock(&sbsec->lock);
568
569 if (!ss_initialized) {
570 if (!num_opts) {
571 /* Defer initialization until selinux_complete_init,
572 after the initial policy is loaded and the security
573 server is ready to handle calls. */
574 goto out;
575 }
576 rc = -EINVAL;
577 printk(KERN_WARNING "SELinux: Unable to set superblock options "
578 "before the security server is initialized\n");
579 goto out;
580 }
581
582 /*
583 * Binary mount data FS will come through this function twice. Once
584 * from an explicit call and once from the generic calls from the vfs.
585 * Since the generic VFS calls will not contain any security mount data
586 * we need to skip the double mount verification.
587 *
588 * This does open a hole in which we will not notice if the first
589 * mount using this sb set explict options and a second mount using
590 * this sb does not set any security options. (The first options
591 * will be used for both mounts)
592 */
593 if ((sbsec->flags & SE_SBINITIALIZED) && (sb->s_type->fs_flags & FS_BINARY_MOUNTDATA)
594 && (num_opts == 0))
595 goto out;
596
597 /*
598 * parse the mount options, check if they are valid sids.
599 * also check if someone is trying to mount the same sb more
600 * than once with different security options.
601 */
602 for (i = 0; i < num_opts; i++) {
603 u32 sid;
604
605 if (flags[i] == SE_SBLABELSUPP)
606 continue;
607 rc = security_context_to_sid(mount_options[i],
608 strlen(mount_options[i]), &sid);
609 if (rc) {
610 printk(KERN_WARNING "SELinux: security_context_to_sid"
611 "(%s) failed for (dev %s, type %s) errno=%d\n",
612 mount_options[i], sb->s_id, name, rc);
613 goto out;
614 }
615 switch (flags[i]) {
616 case FSCONTEXT_MNT:
617 fscontext_sid = sid;
618
619 if (bad_option(sbsec, FSCONTEXT_MNT, sbsec->sid,
620 fscontext_sid))
621 goto out_double_mount;
622
623 sbsec->flags |= FSCONTEXT_MNT;
624 break;
625 case CONTEXT_MNT:
626 context_sid = sid;
627
628 if (bad_option(sbsec, CONTEXT_MNT, sbsec->mntpoint_sid,
629 context_sid))
630 goto out_double_mount;
631
632 sbsec->flags |= CONTEXT_MNT;
633 break;
634 case ROOTCONTEXT_MNT:
635 rootcontext_sid = sid;
636
637 if (bad_option(sbsec, ROOTCONTEXT_MNT, root_isec->sid,
638 rootcontext_sid))
639 goto out_double_mount;
640
641 sbsec->flags |= ROOTCONTEXT_MNT;
642
643 break;
644 case DEFCONTEXT_MNT:
645 defcontext_sid = sid;
646
647 if (bad_option(sbsec, DEFCONTEXT_MNT, sbsec->def_sid,
648 defcontext_sid))
649 goto out_double_mount;
650
651 sbsec->flags |= DEFCONTEXT_MNT;
652
653 break;
654 default:
655 rc = -EINVAL;
656 goto out;
657 }
658 }
659
660 if (sbsec->flags & SE_SBINITIALIZED) {
661 /* previously mounted with options, but not on this attempt? */
662 if ((sbsec->flags & SE_MNTMASK) && !num_opts)
663 goto out_double_mount;
664 rc = 0;
665 goto out;
666 }
667
668 if (strcmp(sb->s_type->name, "proc") == 0)
669 sbsec->flags |= SE_SBPROC;
670
671 /* Determine the labeling behavior to use for this filesystem type. */
672 rc = security_fs_use((sbsec->flags & SE_SBPROC) ? "proc" : sb->s_type->name, &sbsec->behavior, &sbsec->sid);
673 if (rc) {
674 printk(KERN_WARNING "%s: security_fs_use(%s) returned %d\n",
675 __func__, sb->s_type->name, rc);
676 goto out;
677 }
678
679 /* sets the context of the superblock for the fs being mounted. */
680 if (fscontext_sid) {
681 rc = may_context_mount_sb_relabel(fscontext_sid, sbsec, cred);
682 if (rc)
683 goto out;
684
685 sbsec->sid = fscontext_sid;
686 }
687
688 /*
689 * Switch to using mount point labeling behavior.
690 * sets the label used on all file below the mountpoint, and will set
691 * the superblock context if not already set.
692 */
693 if (context_sid) {
694 if (!fscontext_sid) {
695 rc = may_context_mount_sb_relabel(context_sid, sbsec,
696 cred);
697 if (rc)
698 goto out;
699 sbsec->sid = context_sid;
700 } else {
701 rc = may_context_mount_inode_relabel(context_sid, sbsec,
702 cred);
703 if (rc)
704 goto out;
705 }
706 if (!rootcontext_sid)
707 rootcontext_sid = context_sid;
708
709 sbsec->mntpoint_sid = context_sid;
710 sbsec->behavior = SECURITY_FS_USE_MNTPOINT;
711 }
712
713 if (rootcontext_sid) {
714 rc = may_context_mount_inode_relabel(rootcontext_sid, sbsec,
715 cred);
716 if (rc)
717 goto out;
718
719 root_isec->sid = rootcontext_sid;
720 root_isec->initialized = 1;
721 }
722
723 if (defcontext_sid) {
724 if (sbsec->behavior != SECURITY_FS_USE_XATTR) {
725 rc = -EINVAL;
726 printk(KERN_WARNING "SELinux: defcontext option is "
727 "invalid for this filesystem type\n");
728 goto out;
729 }
730
731 if (defcontext_sid != sbsec->def_sid) {
732 rc = may_context_mount_inode_relabel(defcontext_sid,
733 sbsec, cred);
734 if (rc)
735 goto out;
736 }
737
738 sbsec->def_sid = defcontext_sid;
739 }
740
741 rc = sb_finish_set_opts(sb);
742 out:
743 mutex_unlock(&sbsec->lock);
744 return rc;
745 out_double_mount:
746 rc = -EINVAL;
747 printk(KERN_WARNING "SELinux: mount invalid. Same superblock, different "
748 "security settings for (dev %s, type %s)\n", sb->s_id, name);
749 goto out;
750 }
751
752 static void selinux_sb_clone_mnt_opts(const struct super_block *oldsb,
753 struct super_block *newsb)
754 {
755 const struct superblock_security_struct *oldsbsec = oldsb->s_security;
756 struct superblock_security_struct *newsbsec = newsb->s_security;
757
758 int set_fscontext = (oldsbsec->flags & FSCONTEXT_MNT);
759 int set_context = (oldsbsec->flags & CONTEXT_MNT);
760 int set_rootcontext = (oldsbsec->flags & ROOTCONTEXT_MNT);
761
762 /*
763 * if the parent was able to be mounted it clearly had no special lsm
764 * mount options. thus we can safely deal with this superblock later
765 */
766 if (!ss_initialized)
767 return;
768
769 /* how can we clone if the old one wasn't set up?? */
770 BUG_ON(!(oldsbsec->flags & SE_SBINITIALIZED));
771
772 /* if fs is reusing a sb, just let its options stand... */
773 if (newsbsec->flags & SE_SBINITIALIZED)
774 return;
775
776 mutex_lock(&newsbsec->lock);
777
778 newsbsec->flags = oldsbsec->flags;
779
780 newsbsec->sid = oldsbsec->sid;
781 newsbsec->def_sid = oldsbsec->def_sid;
782 newsbsec->behavior = oldsbsec->behavior;
783
784 if (set_context) {
785 u32 sid = oldsbsec->mntpoint_sid;
786
787 if (!set_fscontext)
788 newsbsec->sid = sid;
789 if (!set_rootcontext) {
790 struct inode *newinode = newsb->s_root->d_inode;
791 struct inode_security_struct *newisec = newinode->i_security;
792 newisec->sid = sid;
793 }
794 newsbsec->mntpoint_sid = sid;
795 }
796 if (set_rootcontext) {
797 const struct inode *oldinode = oldsb->s_root->d_inode;
798 const struct inode_security_struct *oldisec = oldinode->i_security;
799 struct inode *newinode = newsb->s_root->d_inode;
800 struct inode_security_struct *newisec = newinode->i_security;
801
802 newisec->sid = oldisec->sid;
803 }
804
805 sb_finish_set_opts(newsb);
806 mutex_unlock(&newsbsec->lock);
807 }
808
809 static int selinux_parse_opts_str(char *options,
810 struct security_mnt_opts *opts)
811 {
812 char *p;
813 char *context = NULL, *defcontext = NULL;
814 char *fscontext = NULL, *rootcontext = NULL;
815 int rc, num_mnt_opts = 0;
816
817 opts->num_mnt_opts = 0;
818
819 /* Standard string-based options. */
820 while ((p = strsep(&options, "|")) != NULL) {
821 int token;
822 substring_t args[MAX_OPT_ARGS];
823
824 if (!*p)
825 continue;
826
827 token = match_token(p, tokens, args);
828
829 switch (token) {
830 case Opt_context:
831 if (context || defcontext) {
832 rc = -EINVAL;
833 printk(KERN_WARNING SEL_MOUNT_FAIL_MSG);
834 goto out_err;
835 }
836 context = match_strdup(&args[0]);
837 if (!context) {
838 rc = -ENOMEM;
839 goto out_err;
840 }
841 break;
842
843 case Opt_fscontext:
844 if (fscontext) {
845 rc = -EINVAL;
846 printk(KERN_WARNING SEL_MOUNT_FAIL_MSG);
847 goto out_err;
848 }
849 fscontext = match_strdup(&args[0]);
850 if (!fscontext) {
851 rc = -ENOMEM;
852 goto out_err;
853 }
854 break;
855
856 case Opt_rootcontext:
857 if (rootcontext) {
858 rc = -EINVAL;
859 printk(KERN_WARNING SEL_MOUNT_FAIL_MSG);
860 goto out_err;
861 }
862 rootcontext = match_strdup(&args[0]);
863 if (!rootcontext) {
864 rc = -ENOMEM;
865 goto out_err;
866 }
867 break;
868
869 case Opt_defcontext:
870 if (context || defcontext) {
871 rc = -EINVAL;
872 printk(KERN_WARNING SEL_MOUNT_FAIL_MSG);
873 goto out_err;
874 }
875 defcontext = match_strdup(&args[0]);
876 if (!defcontext) {
877 rc = -ENOMEM;
878 goto out_err;
879 }
880 break;
881 case Opt_labelsupport:
882 break;
883 default:
884 rc = -EINVAL;
885 printk(KERN_WARNING "SELinux: unknown mount option\n");
886 goto out_err;
887
888 }
889 }
890
891 rc = -ENOMEM;
892 opts->mnt_opts = kcalloc(NUM_SEL_MNT_OPTS, sizeof(char *), GFP_ATOMIC);
893 if (!opts->mnt_opts)
894 goto out_err;
895
896 opts->mnt_opts_flags = kcalloc(NUM_SEL_MNT_OPTS, sizeof(int), GFP_ATOMIC);
897 if (!opts->mnt_opts_flags) {
898 kfree(opts->mnt_opts);
899 goto out_err;
900 }
901
902 if (fscontext) {
903 opts->mnt_opts[num_mnt_opts] = fscontext;
904 opts->mnt_opts_flags[num_mnt_opts++] = FSCONTEXT_MNT;
905 }
906 if (context) {
907 opts->mnt_opts[num_mnt_opts] = context;
908 opts->mnt_opts_flags[num_mnt_opts++] = CONTEXT_MNT;
909 }
910 if (rootcontext) {
911 opts->mnt_opts[num_mnt_opts] = rootcontext;
912 opts->mnt_opts_flags[num_mnt_opts++] = ROOTCONTEXT_MNT;
913 }
914 if (defcontext) {
915 opts->mnt_opts[num_mnt_opts] = defcontext;
916 opts->mnt_opts_flags[num_mnt_opts++] = DEFCONTEXT_MNT;
917 }
918
919 opts->num_mnt_opts = num_mnt_opts;
920 return 0;
921
922 out_err:
923 kfree(context);
924 kfree(defcontext);
925 kfree(fscontext);
926 kfree(rootcontext);
927 return rc;
928 }
929 /*
930 * string mount options parsing and call set the sbsec
931 */
932 static int superblock_doinit(struct super_block *sb, void *data)
933 {
934 int rc = 0;
935 char *options = data;
936 struct security_mnt_opts opts;
937
938 security_init_mnt_opts(&opts);
939
940 if (!data)
941 goto out;
942
943 BUG_ON(sb->s_type->fs_flags & FS_BINARY_MOUNTDATA);
944
945 rc = selinux_parse_opts_str(options, &opts);
946 if (rc)
947 goto out_err;
948
949 out:
950 rc = selinux_set_mnt_opts(sb, &opts);
951
952 out_err:
953 security_free_mnt_opts(&opts);
954 return rc;
955 }
956
957 static void selinux_write_opts(struct seq_file *m,
958 struct security_mnt_opts *opts)
959 {
960 int i;
961 char *prefix;
962
963 for (i = 0; i < opts->num_mnt_opts; i++) {
964 char *has_comma;
965
966 if (opts->mnt_opts[i])
967 has_comma = strchr(opts->mnt_opts[i], ',');
968 else
969 has_comma = NULL;
970
971 switch (opts->mnt_opts_flags[i]) {
972 case CONTEXT_MNT:
973 prefix = CONTEXT_STR;
974 break;
975 case FSCONTEXT_MNT:
976 prefix = FSCONTEXT_STR;
977 break;
978 case ROOTCONTEXT_MNT:
979 prefix = ROOTCONTEXT_STR;
980 break;
981 case DEFCONTEXT_MNT:
982 prefix = DEFCONTEXT_STR;
983 break;
984 case SE_SBLABELSUPP:
985 seq_putc(m, ',');
986 seq_puts(m, LABELSUPP_STR);
987 continue;
988 default:
989 BUG();
990 return;
991 };
992 /* we need a comma before each option */
993 seq_putc(m, ',');
994 seq_puts(m, prefix);
995 if (has_comma)
996 seq_putc(m, '\"');
997 seq_puts(m, opts->mnt_opts[i]);
998 if (has_comma)
999 seq_putc(m, '\"');
1000 }
1001 }
1002
1003 static int selinux_sb_show_options(struct seq_file *m, struct super_block *sb)
1004 {
1005 struct security_mnt_opts opts;
1006 int rc;
1007
1008 rc = selinux_get_mnt_opts(sb, &opts);
1009 if (rc) {
1010 /* before policy load we may get EINVAL, don't show anything */
1011 if (rc == -EINVAL)
1012 rc = 0;
1013 return rc;
1014 }
1015
1016 selinux_write_opts(m, &opts);
1017
1018 security_free_mnt_opts(&opts);
1019
1020 return rc;
1021 }
1022
1023 static inline u16 inode_mode_to_security_class(umode_t mode)
1024 {
1025 switch (mode & S_IFMT) {
1026 case S_IFSOCK:
1027 return SECCLASS_SOCK_FILE;
1028 case S_IFLNK:
1029 return SECCLASS_LNK_FILE;
1030 case S_IFREG:
1031 return SECCLASS_FILE;
1032 case S_IFBLK:
1033 return SECCLASS_BLK_FILE;
1034 case S_IFDIR:
1035 return SECCLASS_DIR;
1036 case S_IFCHR:
1037 return SECCLASS_CHR_FILE;
1038 case S_IFIFO:
1039 return SECCLASS_FIFO_FILE;
1040
1041 }
1042
1043 return SECCLASS_FILE;
1044 }
1045
1046 static inline int default_protocol_stream(int protocol)
1047 {
1048 return (protocol == IPPROTO_IP || protocol == IPPROTO_TCP);
1049 }
1050
1051 static inline int default_protocol_dgram(int protocol)
1052 {
1053 return (protocol == IPPROTO_IP || protocol == IPPROTO_UDP);
1054 }
1055
1056 static inline u16 socket_type_to_security_class(int family, int type, int protocol)
1057 {
1058 switch (family) {
1059 case PF_UNIX:
1060 switch (type) {
1061 case SOCK_STREAM:
1062 case SOCK_SEQPACKET:
1063 return SECCLASS_UNIX_STREAM_SOCKET;
1064 case SOCK_DGRAM:
1065 return SECCLASS_UNIX_DGRAM_SOCKET;
1066 }
1067 break;
1068 case PF_INET:
1069 case PF_INET6:
1070 switch (type) {
1071 case SOCK_STREAM:
1072 if (default_protocol_stream(protocol))
1073 return SECCLASS_TCP_SOCKET;
1074 else
1075 return SECCLASS_RAWIP_SOCKET;
1076 case SOCK_DGRAM:
1077 if (default_protocol_dgram(protocol))
1078 return SECCLASS_UDP_SOCKET;
1079 else
1080 return SECCLASS_RAWIP_SOCKET;
1081 case SOCK_DCCP:
1082 return SECCLASS_DCCP_SOCKET;
1083 default:
1084 return SECCLASS_RAWIP_SOCKET;
1085 }
1086 break;
1087 case PF_NETLINK:
1088 switch (protocol) {
1089 case NETLINK_ROUTE:
1090 return SECCLASS_NETLINK_ROUTE_SOCKET;
1091 case NETLINK_FIREWALL:
1092 return SECCLASS_NETLINK_FIREWALL_SOCKET;
1093 case NETLINK_SOCK_DIAG:
1094 return SECCLASS_NETLINK_TCPDIAG_SOCKET;
1095 case NETLINK_NFLOG:
1096 return SECCLASS_NETLINK_NFLOG_SOCKET;
1097 case NETLINK_XFRM:
1098 return SECCLASS_NETLINK_XFRM_SOCKET;
1099 case NETLINK_SELINUX:
1100 return SECCLASS_NETLINK_SELINUX_SOCKET;
1101 case NETLINK_AUDIT:
1102 return SECCLASS_NETLINK_AUDIT_SOCKET;
1103 case NETLINK_IP6_FW:
1104 return SECCLASS_NETLINK_IP6FW_SOCKET;
1105 case NETLINK_DNRTMSG:
1106 return SECCLASS_NETLINK_DNRT_SOCKET;
1107 case NETLINK_KOBJECT_UEVENT:
1108 return SECCLASS_NETLINK_KOBJECT_UEVENT_SOCKET;
1109 default:
1110 return SECCLASS_NETLINK_SOCKET;
1111 }
1112 case PF_PACKET:
1113 return SECCLASS_PACKET_SOCKET;
1114 case PF_KEY:
1115 return SECCLASS_KEY_SOCKET;
1116 case PF_APPLETALK:
1117 return SECCLASS_APPLETALK_SOCKET;
1118 }
1119
1120 return SECCLASS_SOCKET;
1121 }
1122
1123 #ifdef CONFIG_PROC_FS
1124 static int selinux_proc_get_sid(struct dentry *dentry,
1125 u16 tclass,
1126 u32 *sid)
1127 {
1128 int rc;
1129 char *buffer, *path;
1130
1131 buffer = (char *)__get_free_page(GFP_KERNEL);
1132 if (!buffer)
1133 return -ENOMEM;
1134
1135 path = dentry_path_raw(dentry, buffer, PAGE_SIZE);
1136 if (IS_ERR(path))
1137 rc = PTR_ERR(path);
1138 else {
1139 /* each process gets a /proc/PID/ entry. Strip off the
1140 * PID part to get a valid selinux labeling.
1141 * e.g. /proc/1/net/rpc/nfs -> /net/rpc/nfs */
1142 while (path[1] >= '0' && path[1] <= '9') {
1143 path[1] = '/';
1144 path++;
1145 }
1146 rc = security_genfs_sid("proc", path, tclass, sid);
1147 }
1148 free_page((unsigned long)buffer);
1149 return rc;
1150 }
1151 #else
1152 static int selinux_proc_get_sid(struct dentry *dentry,
1153 u16 tclass,
1154 u32 *sid)
1155 {
1156 return -EINVAL;
1157 }
1158 #endif
1159
1160 /* The inode's security attributes must be initialized before first use. */
1161 static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dentry)
1162 {
1163 struct superblock_security_struct *sbsec = NULL;
1164 struct inode_security_struct *isec = inode->i_security;
1165 u32 sid;
1166 struct dentry *dentry;
1167 #define INITCONTEXTLEN 255
1168 char *context = NULL;
1169 unsigned len = 0;
1170 int rc = 0;
1171
1172 if (isec->initialized)
1173 goto out;
1174
1175 mutex_lock(&isec->lock);
1176 if (isec->initialized)
1177 goto out_unlock;
1178
1179 sbsec = inode->i_sb->s_security;
1180 if (!(sbsec->flags & SE_SBINITIALIZED)) {
1181 /* Defer initialization until selinux_complete_init,
1182 after the initial policy is loaded and the security
1183 server is ready to handle calls. */
1184 spin_lock(&sbsec->isec_lock);
1185 if (list_empty(&isec->list))
1186 list_add(&isec->list, &sbsec->isec_head);
1187 spin_unlock(&sbsec->isec_lock);
1188 goto out_unlock;
1189 }
1190
1191 switch (sbsec->behavior) {
1192 case SECURITY_FS_USE_XATTR:
1193 if (!inode->i_op->getxattr) {
1194 isec->sid = sbsec->def_sid;
1195 break;
1196 }
1197
1198 /* Need a dentry, since the xattr API requires one.
1199 Life would be simpler if we could just pass the inode. */
1200 if (opt_dentry) {
1201 /* Called from d_instantiate or d_splice_alias. */
1202 dentry = dget(opt_dentry);
1203 } else {
1204 /* Called from selinux_complete_init, try to find a dentry. */
1205 dentry = d_find_alias(inode);
1206 }
1207 if (!dentry) {
1208 /*
1209 * this is can be hit on boot when a file is accessed
1210 * before the policy is loaded. When we load policy we
1211 * may find inodes that have no dentry on the
1212 * sbsec->isec_head list. No reason to complain as these
1213 * will get fixed up the next time we go through
1214 * inode_doinit with a dentry, before these inodes could
1215 * be used again by userspace.
1216 */
1217 goto out_unlock;
1218 }
1219
1220 len = INITCONTEXTLEN;
1221 context = kmalloc(len+1, GFP_NOFS);
1222 if (!context) {
1223 rc = -ENOMEM;
1224 dput(dentry);
1225 goto out_unlock;
1226 }
1227 context[len] = '\0';
1228 rc = inode->i_op->getxattr(dentry, XATTR_NAME_SELINUX,
1229 context, len);
1230 if (rc == -ERANGE) {
1231 kfree(context);
1232
1233 /* Need a larger buffer. Query for the right size. */
1234 rc = inode->i_op->getxattr(dentry, XATTR_NAME_SELINUX,
1235 NULL, 0);
1236 if (rc < 0) {
1237 dput(dentry);
1238 goto out_unlock;
1239 }
1240 len = rc;
1241 context = kmalloc(len+1, GFP_NOFS);
1242 if (!context) {
1243 rc = -ENOMEM;
1244 dput(dentry);
1245 goto out_unlock;
1246 }
1247 context[len] = '\0';
1248 rc = inode->i_op->getxattr(dentry,
1249 XATTR_NAME_SELINUX,
1250 context, len);
1251 }
1252 dput(dentry);
1253 if (rc < 0) {
1254 if (rc != -ENODATA) {
1255 printk(KERN_WARNING "SELinux: %s: getxattr returned "
1256 "%d for dev=%s ino=%ld\n", __func__,
1257 -rc, inode->i_sb->s_id, inode->i_ino);
1258 kfree(context);
1259 goto out_unlock;
1260 }
1261 /* Map ENODATA to the default file SID */
1262 sid = sbsec->def_sid;
1263 rc = 0;
1264 } else {
1265 rc = security_context_to_sid_default(context, rc, &sid,
1266 sbsec->def_sid,
1267 GFP_NOFS);
1268 if (rc) {
1269 char *dev = inode->i_sb->s_id;
1270 unsigned long ino = inode->i_ino;
1271
1272 if (rc == -EINVAL) {
1273 if (printk_ratelimit())
1274 printk(KERN_NOTICE "SELinux: inode=%lu on dev=%s was found to have an invalid "
1275 "context=%s. This indicates you may need to relabel the inode or the "
1276 "filesystem in question.\n", ino, dev, context);
1277 } else {
1278 printk(KERN_WARNING "SELinux: %s: context_to_sid(%s) "
1279 "returned %d for dev=%s ino=%ld\n",
1280 __func__, context, -rc, dev, ino);
1281 }
1282 kfree(context);
1283 /* Leave with the unlabeled SID */
1284 rc = 0;
1285 break;
1286 }
1287 }
1288 kfree(context);
1289 isec->sid = sid;
1290 break;
1291 case SECURITY_FS_USE_TASK:
1292 isec->sid = isec->task_sid;
1293 break;
1294 case SECURITY_FS_USE_TRANS:
1295 /* Default to the fs SID. */
1296 isec->sid = sbsec->sid;
1297
1298 /* Try to obtain a transition SID. */
1299 isec->sclass = inode_mode_to_security_class(inode->i_mode);
1300 rc = security_transition_sid(isec->task_sid, sbsec->sid,
1301 isec->sclass, NULL, &sid);
1302 if (rc)
1303 goto out_unlock;
1304 isec->sid = sid;
1305 break;
1306 case SECURITY_FS_USE_MNTPOINT:
1307 isec->sid = sbsec->mntpoint_sid;
1308 break;
1309 default:
1310 /* Default to the fs superblock SID. */
1311 isec->sid = sbsec->sid;
1312
1313 if ((sbsec->flags & SE_SBPROC) && !S_ISLNK(inode->i_mode)) {
1314 if (opt_dentry) {
1315 isec->sclass = inode_mode_to_security_class(inode->i_mode);
1316 rc = selinux_proc_get_sid(opt_dentry,
1317 isec->sclass,
1318 &sid);
1319 if (rc)
1320 goto out_unlock;
1321 isec->sid = sid;
1322 }
1323 }
1324 break;
1325 }
1326
1327 isec->initialized = 1;
1328
1329 out_unlock:
1330 mutex_unlock(&isec->lock);
1331 out:
1332 if (isec->sclass == SECCLASS_FILE)
1333 isec->sclass = inode_mode_to_security_class(inode->i_mode);
1334 return rc;
1335 }
1336
1337 /* Convert a Linux signal to an access vector. */
1338 static inline u32 signal_to_av(int sig)
1339 {
1340 u32 perm = 0;
1341
1342 switch (sig) {
1343 case SIGCHLD:
1344 /* Commonly granted from child to parent. */
1345 perm = PROCESS__SIGCHLD;
1346 break;
1347 case SIGKILL:
1348 /* Cannot be caught or ignored */
1349 perm = PROCESS__SIGKILL;
1350 break;
1351 case SIGSTOP:
1352 /* Cannot be caught or ignored */
1353 perm = PROCESS__SIGSTOP;
1354 break;
1355 default:
1356 /* All other signals. */
1357 perm = PROCESS__SIGNAL;
1358 break;
1359 }
1360
1361 return perm;
1362 }
1363
1364 /*
1365 * Check permission between a pair of credentials
1366 * fork check, ptrace check, etc.
1367 */
1368 static int cred_has_perm(const struct cred *actor,
1369 const struct cred *target,
1370 u32 perms)
1371 {
1372 u32 asid = cred_sid(actor), tsid = cred_sid(target);
1373
1374 return avc_has_perm(asid, tsid, SECCLASS_PROCESS, perms, NULL);
1375 }
1376
1377 /*
1378 * Check permission between a pair of tasks, e.g. signal checks,
1379 * fork check, ptrace check, etc.
1380 * tsk1 is the actor and tsk2 is the target
1381 * - this uses the default subjective creds of tsk1
1382 */
1383 static int task_has_perm(const struct task_struct *tsk1,
1384 const struct task_struct *tsk2,
1385 u32 perms)
1386 {
1387 const struct task_security_struct *__tsec1, *__tsec2;
1388 u32 sid1, sid2;
1389
1390 rcu_read_lock();
1391 __tsec1 = __task_cred(tsk1)->security; sid1 = __tsec1->sid;
1392 __tsec2 = __task_cred(tsk2)->security; sid2 = __tsec2->sid;
1393 rcu_read_unlock();
1394 return avc_has_perm(sid1, sid2, SECCLASS_PROCESS, perms, NULL);
1395 }
1396
1397 /*
1398 * Check permission between current and another task, e.g. signal checks,
1399 * fork check, ptrace check, etc.
1400 * current is the actor and tsk2 is the target
1401 * - this uses current's subjective creds
1402 */
1403 static int current_has_perm(const struct task_struct *tsk,
1404 u32 perms)
1405 {
1406 u32 sid, tsid;
1407
1408 sid = current_sid();
1409 tsid = task_sid(tsk);
1410 return avc_has_perm(sid, tsid, SECCLASS_PROCESS, perms, NULL);
1411 }
1412
1413 #if CAP_LAST_CAP > 63
1414 #error Fix SELinux to handle capabilities > 63.
1415 #endif
1416
1417 /* Check whether a task is allowed to use a capability. */
1418 static int cred_has_capability(const struct cred *cred,
1419 int cap, int audit)
1420 {
1421 struct common_audit_data ad;
1422 struct av_decision avd;
1423 u16 sclass;
1424 u32 sid = cred_sid(cred);
1425 u32 av = CAP_TO_MASK(cap);
1426 int rc;
1427
1428 COMMON_AUDIT_DATA_INIT(&ad, CAP);
1429 ad.tsk = current;
1430 ad.u.cap = cap;
1431
1432 switch (CAP_TO_INDEX(cap)) {
1433 case 0:
1434 sclass = SECCLASS_CAPABILITY;
1435 break;
1436 case 1:
1437 sclass = SECCLASS_CAPABILITY2;
1438 break;
1439 default:
1440 printk(KERN_ERR
1441 "SELinux: out of range capability %d\n", cap);
1442 BUG();
1443 return -EINVAL;
1444 }
1445
1446 rc = avc_has_perm_noaudit(sid, sid, sclass, av, 0, &avd);
1447 if (audit == SECURITY_CAP_AUDIT) {
1448 int rc2 = avc_audit(sid, sid, sclass, av, &avd, rc, &ad, 0);
1449 if (rc2)
1450 return rc2;
1451 }
1452 return rc;
1453 }
1454
1455 /* Check whether a task is allowed to use a system operation. */
1456 static int task_has_system(struct task_struct *tsk,
1457 u32 perms)
1458 {
1459 u32 sid = task_sid(tsk);
1460
1461 return avc_has_perm(sid, SECINITSID_KERNEL,
1462 SECCLASS_SYSTEM, perms, NULL);
1463 }
1464
1465 /* Check whether a task has a particular permission to an inode.
1466 The 'adp' parameter is optional and allows other audit
1467 data to be passed (e.g. the dentry). */
1468 static int inode_has_perm(const struct cred *cred,
1469 struct inode *inode,
1470 u32 perms,
1471 struct common_audit_data *adp,
1472 unsigned flags)
1473 {
1474 struct inode_security_struct *isec;
1475 u32 sid;
1476
1477 validate_creds(cred);
1478
1479 if (unlikely(IS_PRIVATE(inode)))
1480 return 0;
1481
1482 sid = cred_sid(cred);
1483 isec = inode->i_security;
1484
1485 return avc_has_perm_flags(sid, isec->sid, isec->sclass, perms, adp, flags);
1486 }
1487
1488 static int inode_has_perm_noadp(const struct cred *cred,
1489 struct inode *inode,
1490 u32 perms,
1491 unsigned flags)
1492 {
1493 struct common_audit_data ad;
1494
1495 COMMON_AUDIT_DATA_INIT(&ad, INODE);
1496 ad.u.inode = inode;
1497 return inode_has_perm(cred, inode, perms, &ad, flags);
1498 }
1499
1500 /* Same as inode_has_perm, but pass explicit audit data containing
1501 the dentry to help the auditing code to more easily generate the
1502 pathname if needed. */
1503 static inline int dentry_has_perm(const struct cred *cred,
1504 struct dentry *dentry,
1505 u32 av)
1506 {
1507 struct inode *inode = dentry->d_inode;
1508 struct common_audit_data ad;
1509
1510 COMMON_AUDIT_DATA_INIT(&ad, DENTRY);
1511 ad.u.dentry = dentry;
1512 return inode_has_perm(cred, inode, av, &ad, 0);
1513 }
1514
1515 /* Same as inode_has_perm, but pass explicit audit data containing
1516 the path to help the auditing code to more easily generate the
1517 pathname if needed. */
1518 static inline int path_has_perm(const struct cred *cred,
1519 struct path *path,
1520 u32 av)
1521 {
1522 struct inode *inode = path->dentry->d_inode;
1523 struct common_audit_data ad;
1524
1525 COMMON_AUDIT_DATA_INIT(&ad, PATH);
1526 ad.u.path = *path;
1527 return inode_has_perm(cred, inode, av, &ad, 0);
1528 }
1529
1530 /* Check whether a task can use an open file descriptor to
1531 access an inode in a given way. Check access to the
1532 descriptor itself, and then use dentry_has_perm to
1533 check a particular permission to the file.
1534 Access to the descriptor is implicitly granted if it
1535 has the same SID as the process. If av is zero, then
1536 access to the file is not checked, e.g. for cases
1537 where only the descriptor is affected like seek. */
1538 static int file_has_perm(const struct cred *cred,
1539 struct file *file,
1540 u32 av)
1541 {
1542 struct file_security_struct *fsec = file->f_security;
1543 struct inode *inode = file->f_path.dentry->d_inode;
1544 struct common_audit_data ad;
1545 u32 sid = cred_sid(cred);
1546 int rc;
1547
1548 COMMON_AUDIT_DATA_INIT(&ad, PATH);
1549 ad.u.path = file->f_path;
1550
1551 if (sid != fsec->sid) {
1552 rc = avc_has_perm(sid, fsec->sid,
1553 SECCLASS_FD,
1554 FD__USE,
1555 &ad);
1556 if (rc)
1557 goto out;
1558 }
1559
1560 /* av is zero if only checking access to the descriptor. */
1561 rc = 0;
1562 if (av)
1563 rc = inode_has_perm(cred, inode, av, &ad, 0);
1564
1565 out:
1566 return rc;
1567 }
1568
1569 /* Check whether a task can create a file. */
1570 static int may_create(struct inode *dir,
1571 struct dentry *dentry,
1572 u16 tclass)
1573 {
1574 const struct task_security_struct *tsec = current_security();
1575 struct inode_security_struct *dsec;
1576 struct superblock_security_struct *sbsec;
1577 u32 sid, newsid;
1578 struct common_audit_data ad;
1579 int rc;
1580
1581 dsec = dir->i_security;
1582 sbsec = dir->i_sb->s_security;
1583
1584 sid = tsec->sid;
1585 newsid = tsec->create_sid;
1586
1587 COMMON_AUDIT_DATA_INIT(&ad, DENTRY);
1588 ad.u.dentry = dentry;
1589
1590 rc = avc_has_perm(sid, dsec->sid, SECCLASS_DIR,
1591 DIR__ADD_NAME | DIR__SEARCH,
1592 &ad);
1593 if (rc)
1594 return rc;
1595
1596 if (!newsid || !(sbsec->flags & SE_SBLABELSUPP)) {
1597 rc = security_transition_sid(sid, dsec->sid, tclass,
1598 &dentry->d_name, &newsid);
1599 if (rc)
1600 return rc;
1601 }
1602
1603 rc = avc_has_perm(sid, newsid, tclass, FILE__CREATE, &ad);
1604 if (rc)
1605 return rc;
1606
1607 return avc_has_perm(newsid, sbsec->sid,
1608 SECCLASS_FILESYSTEM,
1609 FILESYSTEM__ASSOCIATE, &ad);
1610 }
1611
1612 /* Check whether a task can create a key. */
1613 static int may_create_key(u32 ksid,
1614 struct task_struct *ctx)
1615 {
1616 u32 sid = task_sid(ctx);
1617
1618 return avc_has_perm(sid, ksid, SECCLASS_KEY, KEY__CREATE, NULL);
1619 }
1620
1621 #define MAY_LINK 0
1622 #define MAY_UNLINK 1
1623 #define MAY_RMDIR 2
1624
1625 /* Check whether a task can link, unlink, or rmdir a file/directory. */
1626 static int may_link(struct inode *dir,
1627 struct dentry *dentry,
1628 int kind)
1629
1630 {
1631 struct inode_security_struct *dsec, *isec;
1632 struct common_audit_data ad;
1633 u32 sid = current_sid();
1634 u32 av;
1635 int rc;
1636
1637 dsec = dir->i_security;
1638 isec = dentry->d_inode->i_security;
1639
1640 COMMON_AUDIT_DATA_INIT(&ad, DENTRY);
1641 ad.u.dentry = dentry;
1642
1643 av = DIR__SEARCH;
1644 av |= (kind ? DIR__REMOVE_NAME : DIR__ADD_NAME);
1645 rc = avc_has_perm(sid, dsec->sid, SECCLASS_DIR, av, &ad);
1646 if (rc)
1647 return rc;
1648
1649 switch (kind) {
1650 case MAY_LINK:
1651 av = FILE__LINK;
1652 break;
1653 case MAY_UNLINK:
1654 av = FILE__UNLINK;
1655 break;
1656 case MAY_RMDIR:
1657 av = DIR__RMDIR;
1658 break;
1659 default:
1660 printk(KERN_WARNING "SELinux: %s: unrecognized kind %d\n",
1661 __func__, kind);
1662 return 0;
1663 }
1664
1665 rc = avc_has_perm(sid, isec->sid, isec->sclass, av, &ad);
1666 return rc;
1667 }
1668
1669 static inline int may_rename(struct inode *old_dir,
1670 struct dentry *old_dentry,
1671 struct inode *new_dir,
1672 struct dentry *new_dentry)
1673 {
1674 struct inode_security_struct *old_dsec, *new_dsec, *old_isec, *new_isec;
1675 struct common_audit_data ad;
1676 u32 sid = current_sid();
1677 u32 av;
1678 int old_is_dir, new_is_dir;
1679 int rc;
1680
1681 old_dsec = old_dir->i_security;
1682 old_isec = old_dentry->d_inode->i_security;
1683 old_is_dir = S_ISDIR(old_dentry->d_inode->i_mode);
1684 new_dsec = new_dir->i_security;
1685
1686 COMMON_AUDIT_DATA_INIT(&ad, DENTRY);
1687
1688 ad.u.dentry = old_dentry;
1689 rc = avc_has_perm(sid, old_dsec->sid, SECCLASS_DIR,
1690 DIR__REMOVE_NAME | DIR__SEARCH, &ad);
1691 if (rc)
1692 return rc;
1693 rc = avc_has_perm(sid, old_isec->sid,
1694 old_isec->sclass, FILE__RENAME, &ad);
1695 if (rc)
1696 return rc;
1697 if (old_is_dir && new_dir != old_dir) {
1698 rc = avc_has_perm(sid, old_isec->sid,
1699 old_isec->sclass, DIR__REPARENT, &ad);
1700 if (rc)
1701 return rc;
1702 }
1703
1704 ad.u.dentry = new_dentry;
1705 av = DIR__ADD_NAME | DIR__SEARCH;
1706 if (new_dentry->d_inode)
1707 av |= DIR__REMOVE_NAME;
1708 rc = avc_has_perm(sid, new_dsec->sid, SECCLASS_DIR, av, &ad);
1709 if (rc)
1710 return rc;
1711 if (new_dentry->d_inode) {
1712 new_isec = new_dentry->d_inode->i_security;
1713 new_is_dir = S_ISDIR(new_dentry->d_inode->i_mode);
1714 rc = avc_has_perm(sid, new_isec->sid,
1715 new_isec->sclass,
1716 (new_is_dir ? DIR__RMDIR : FILE__UNLINK), &ad);
1717 if (rc)
1718 return rc;
1719 }
1720
1721 return 0;
1722 }
1723
1724 /* Check whether a task can perform a filesystem operation. */
1725 static int superblock_has_perm(const struct cred *cred,
1726 struct super_block *sb,
1727 u32 perms,
1728 struct common_audit_data *ad)
1729 {
1730 struct superblock_security_struct *sbsec;
1731 u32 sid = cred_sid(cred);
1732
1733 sbsec = sb->s_security;
1734 return avc_has_perm(sid, sbsec->sid, SECCLASS_FILESYSTEM, perms, ad);
1735 }
1736
1737 /* Convert a Linux mode and permission mask to an access vector. */
1738 static inline u32 file_mask_to_av(int mode, int mask)
1739 {
1740 u32 av = 0;
1741
1742 if (!S_ISDIR(mode)) {
1743 if (mask & MAY_EXEC)
1744 av |= FILE__EXECUTE;
1745 if (mask & MAY_READ)
1746 av |= FILE__READ;
1747
1748 if (mask & MAY_APPEND)
1749 av |= FILE__APPEND;
1750 else if (mask & MAY_WRITE)
1751 av |= FILE__WRITE;
1752
1753 } else {
1754 if (mask & MAY_EXEC)
1755 av |= DIR__SEARCH;
1756 if (mask & MAY_WRITE)
1757 av |= DIR__WRITE;
1758 if (mask & MAY_READ)
1759 av |= DIR__READ;
1760 }
1761
1762 return av;
1763 }
1764
1765 /* Convert a Linux file to an access vector. */
1766 static inline u32 file_to_av(struct file *file)
1767 {
1768 u32 av = 0;
1769
1770 if (file->f_mode & FMODE_READ)
1771 av |= FILE__READ;
1772 if (file->f_mode & FMODE_WRITE) {
1773 if (file->f_flags & O_APPEND)
1774 av |= FILE__APPEND;
1775 else
1776 av |= FILE__WRITE;
1777 }
1778 if (!av) {
1779 /*
1780 * Special file opened with flags 3 for ioctl-only use.
1781 */
1782 av = FILE__IOCTL;
1783 }
1784
1785 return av;
1786 }
1787
1788 /*
1789 * Convert a file to an access vector and include the correct open
1790 * open permission.
1791 */
1792 static inline u32 open_file_to_av(struct file *file)
1793 {
1794 u32 av = file_to_av(file);
1795
1796 if (selinux_policycap_openperm)
1797 av |= FILE__OPEN;
1798
1799 return av;
1800 }
1801
1802 /* Hook functions begin here. */
1803
1804 static int selinux_ptrace_access_check(struct task_struct *child,
1805 unsigned int mode)
1806 {
1807 int rc;
1808
1809 rc = cap_ptrace_access_check(child, mode);
1810 if (rc)
1811 return rc;
1812
1813 if (mode & PTRACE_MODE_READ) {
1814 u32 sid = current_sid();
1815 u32 csid = task_sid(child);
1816 return avc_has_perm(sid, csid, SECCLASS_FILE, FILE__READ, NULL);
1817 }
1818
1819 return current_has_perm(child, PROCESS__PTRACE);
1820 }
1821
1822 static int selinux_ptrace_traceme(struct task_struct *parent)
1823 {
1824 int rc;
1825
1826 rc = cap_ptrace_traceme(parent);
1827 if (rc)
1828 return rc;
1829
1830 return task_has_perm(parent, current, PROCESS__PTRACE);
1831 }
1832
1833 static int selinux_capget(struct task_struct *target, kernel_cap_t *effective,
1834 kernel_cap_t *inheritable, kernel_cap_t *permitted)
1835 {
1836 int error;
1837
1838 error = current_has_perm(target, PROCESS__GETCAP);
1839 if (error)
1840 return error;
1841
1842 return cap_capget(target, effective, inheritable, permitted);
1843 }
1844
1845 static int selinux_capset(struct cred *new, const struct cred *old,
1846 const kernel_cap_t *effective,
1847 const kernel_cap_t *inheritable,
1848 const kernel_cap_t *permitted)
1849 {
1850 int error;
1851
1852 error = cap_capset(new, old,
1853 effective, inheritable, permitted);
1854 if (error)
1855 return error;
1856
1857 return cred_has_perm(old, new, PROCESS__SETCAP);
1858 }
1859
1860 /*
1861 * (This comment used to live with the selinux_task_setuid hook,
1862 * which was removed).
1863 *
1864 * Since setuid only affects the current process, and since the SELinux
1865 * controls are not based on the Linux identity attributes, SELinux does not
1866 * need to control this operation. However, SELinux does control the use of
1867 * the CAP_SETUID and CAP_SETGID capabilities using the capable hook.
1868 */
1869
1870 static int selinux_capable(const struct cred *cred, struct user_namespace *ns,
1871 int cap, int audit)
1872 {
1873 int rc;
1874
1875 rc = cap_capable(cred, ns, cap, audit);
1876 if (rc)
1877 return rc;
1878
1879 return cred_has_capability(cred, cap, audit);
1880 }
1881
1882 static int selinux_quotactl(int cmds, int type, int id, struct super_block *sb)
1883 {
1884 const struct cred *cred = current_cred();
1885 int rc = 0;
1886
1887 if (!sb)
1888 return 0;
1889
1890 switch (cmds) {
1891 case Q_SYNC:
1892 case Q_QUOTAON:
1893 case Q_QUOTAOFF:
1894 case Q_SETINFO:
1895 case Q_SETQUOTA:
1896 rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAMOD, NULL);
1897 break;
1898 case Q_GETFMT:
1899 case Q_GETINFO:
1900 case Q_GETQUOTA:
1901 rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAGET, NULL);
1902 break;
1903 default:
1904 rc = 0; /* let the kernel handle invalid cmds */
1905 break;
1906 }
1907 return rc;
1908 }
1909
1910 static int selinux_quota_on(struct dentry *dentry)
1911 {
1912 const struct cred *cred = current_cred();
1913
1914 return dentry_has_perm(cred, dentry, FILE__QUOTAON);
1915 }
1916
1917 static int selinux_syslog(int type)
1918 {
1919 int rc;
1920
1921 switch (type) {
1922 case SYSLOG_ACTION_READ_ALL: /* Read last kernel messages */
1923 case SYSLOG_ACTION_SIZE_BUFFER: /* Return size of the log buffer */
1924 rc = task_has_system(current, SYSTEM__SYSLOG_READ);
1925 break;
1926 case SYSLOG_ACTION_CONSOLE_OFF: /* Disable logging to console */
1927 case SYSLOG_ACTION_CONSOLE_ON: /* Enable logging to console */
1928 /* Set level of messages printed to console */
1929 case SYSLOG_ACTION_CONSOLE_LEVEL:
1930 rc = task_has_system(current, SYSTEM__SYSLOG_CONSOLE);
1931 break;
1932 case SYSLOG_ACTION_CLOSE: /* Close log */
1933 case SYSLOG_ACTION_OPEN: /* Open log */
1934 case SYSLOG_ACTION_READ: /* Read from log */
1935 case SYSLOG_ACTION_READ_CLEAR: /* Read/clear last kernel messages */
1936 case SYSLOG_ACTION_CLEAR: /* Clear ring buffer */
1937 default:
1938 rc = task_has_system(current, SYSTEM__SYSLOG_MOD);
1939 break;
1940 }
1941 return rc;
1942 }
1943
1944 /*
1945 * Check that a process has enough memory to allocate a new virtual
1946 * mapping. 0 means there is enough memory for the allocation to
1947 * succeed and -ENOMEM implies there is not.
1948 *
1949 * Do not audit the selinux permission check, as this is applied to all
1950 * processes that allocate mappings.
1951 */
1952 static int selinux_vm_enough_memory(struct mm_struct *mm, long pages)
1953 {
1954 int rc, cap_sys_admin = 0;
1955
1956 rc = selinux_capable(current_cred(), &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 = ptrace_parent(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 /* Derived from fs/exec.c:flush_old_files. */
2096 static inline void flush_unauthorized_files(const struct cred *cred,
2097 struct files_struct *files)
2098 {
2099 struct common_audit_data ad;
2100 struct file *file, *devnull = NULL;
2101 struct tty_struct *tty;
2102 struct fdtable *fdt;
2103 long j = -1;
2104 int drop_tty = 0;
2105
2106 tty = get_current_tty();
2107 if (tty) {
2108 spin_lock(&tty_files_lock);
2109 if (!list_empty(&tty->tty_files)) {
2110 struct tty_file_private *file_priv;
2111 struct inode *inode;
2112
2113 /* Revalidate access to controlling tty.
2114 Use inode_has_perm on the tty inode directly rather
2115 than using file_has_perm, as this particular open
2116 file may belong to another process and we are only
2117 interested in the inode-based check here. */
2118 file_priv = list_first_entry(&tty->tty_files,
2119 struct tty_file_private, list);
2120 file = file_priv->file;
2121 inode = file->f_path.dentry->d_inode;
2122 if (inode_has_perm_noadp(cred, inode,
2123 FILE__READ | FILE__WRITE, 0)) {
2124 drop_tty = 1;
2125 }
2126 }
2127 spin_unlock(&tty_files_lock);
2128 tty_kref_put(tty);
2129 }
2130 /* Reset controlling tty. */
2131 if (drop_tty)
2132 no_tty();
2133
2134 /* Revalidate access to inherited open files. */
2135
2136 COMMON_AUDIT_DATA_INIT(&ad, INODE);
2137
2138 spin_lock(&files->file_lock);
2139 for (;;) {
2140 unsigned long set, i;
2141 int fd;
2142
2143 j++;
2144 i = j * __NFDBITS;
2145 fdt = files_fdtable(files);
2146 if (i >= fdt->max_fds)
2147 break;
2148 set = fdt->open_fds->fds_bits[j];
2149 if (!set)
2150 continue;
2151 spin_unlock(&files->file_lock);
2152 for ( ; set ; i++, set >>= 1) {
2153 if (set & 1) {
2154 file = fget(i);
2155 if (!file)
2156 continue;
2157 if (file_has_perm(cred,
2158 file,
2159 file_to_av(file))) {
2160 sys_close(i);
2161 fd = get_unused_fd();
2162 if (fd != i) {
2163 if (fd >= 0)
2164 put_unused_fd(fd);
2165 fput(file);
2166 continue;
2167 }
2168 if (devnull) {
2169 get_file(devnull);
2170 } else {
2171 devnull = dentry_open(
2172 dget(selinux_null),
2173 mntget(selinuxfs_mount),
2174 O_RDWR, cred);
2175 if (IS_ERR(devnull)) {
2176 devnull = NULL;
2177 put_unused_fd(fd);
2178 fput(file);
2179 continue;
2180 }
2181 }
2182 fd_install(fd, devnull);
2183 }
2184 fput(file);
2185 }
2186 }
2187 spin_lock(&files->file_lock);
2188
2189 }
2190 spin_unlock(&files->file_lock);
2191 }
2192
2193 /*
2194 * Prepare a process for imminent new credential changes due to exec
2195 */
2196 static void selinux_bprm_committing_creds(struct linux_binprm *bprm)
2197 {
2198 struct task_security_struct *new_tsec;
2199 struct rlimit *rlim, *initrlim;
2200 int rc, i;
2201
2202 new_tsec = bprm->cred->security;
2203 if (new_tsec->sid == new_tsec->osid)
2204 return;
2205
2206 /* Close files for which the new task SID is not authorized. */
2207 flush_unauthorized_files(bprm->cred, current->files);
2208
2209 /* Always clear parent death signal on SID transitions. */
2210 current->pdeath_signal = 0;
2211
2212 /* Check whether the new SID can inherit resource limits from the old
2213 * SID. If not, reset all soft limits to the lower of the current
2214 * task's hard limit and the init task's soft limit.
2215 *
2216 * Note that the setting of hard limits (even to lower them) can be
2217 * controlled by the setrlimit check. The inclusion of the init task's
2218 * soft limit into the computation is to avoid resetting soft limits
2219 * higher than the default soft limit for cases where the default is
2220 * lower than the hard limit, e.g. RLIMIT_CORE or RLIMIT_STACK.
2221 */
2222 rc = avc_has_perm(new_tsec->osid, new_tsec->sid, SECCLASS_PROCESS,
2223 PROCESS__RLIMITINH, NULL);
2224 if (rc) {
2225 /* protect against do_prlimit() */
2226 task_lock(current);
2227 for (i = 0; i < RLIM_NLIMITS; i++) {
2228 rlim = current->signal->rlim + i;
2229 initrlim = init_task.signal->rlim + i;
2230 rlim->rlim_cur = min(rlim->rlim_max, initrlim->rlim_cur);
2231 }
2232 task_unlock(current);
2233 update_rlimit_cpu(current, rlimit(RLIMIT_CPU));
2234 }
2235 }
2236
2237 /*
2238 * Clean up the process immediately after the installation of new credentials
2239 * due to exec
2240 */
2241 static void selinux_bprm_committed_creds(struct linux_binprm *bprm)
2242 {
2243 const struct task_security_struct *tsec = current_security();
2244 struct itimerval itimer;
2245 u32 osid, sid;
2246 int rc, i;
2247
2248 osid = tsec->osid;
2249 sid = tsec->sid;
2250
2251 if (sid == osid)
2252 return;
2253
2254 /* Check whether the new SID can inherit signal state from the old SID.
2255 * If not, clear itimers to avoid subsequent signal generation and
2256 * flush and unblock signals.
2257 *
2258 * This must occur _after_ the task SID has been updated so that any
2259 * kill done after the flush will be checked against the new SID.
2260 */
2261 rc = avc_has_perm(osid, sid, SECCLASS_PROCESS, PROCESS__SIGINH, NULL);
2262 if (rc) {
2263 memset(&itimer, 0, sizeof itimer);
2264 for (i = 0; i < 3; i++)
2265 do_setitimer(i, &itimer, NULL);
2266 spin_lock_irq(&current->sighand->siglock);
2267 if (!(current->signal->flags & SIGNAL_GROUP_EXIT)) {
2268 __flush_signals(current);
2269 flush_signal_handlers(current, 1);
2270 sigemptyset(&current->blocked);
2271 }
2272 spin_unlock_irq(&current->sighand->siglock);
2273 }
2274
2275 /* Wake up the parent if it is waiting so that it can recheck
2276 * wait permission to the new task SID. */
2277 read_lock(&tasklist_lock);
2278 __wake_up_parent(current, current->real_parent);
2279 read_unlock(&tasklist_lock);
2280 }
2281
2282 /* superblock security operations */
2283
2284 static int selinux_sb_alloc_security(struct super_block *sb)
2285 {
2286 return superblock_alloc_security(sb);
2287 }
2288
2289 static void selinux_sb_free_security(struct super_block *sb)
2290 {
2291 superblock_free_security(sb);
2292 }
2293
2294 static inline int match_prefix(char *prefix, int plen, char *option, int olen)
2295 {
2296 if (plen > olen)
2297 return 0;
2298
2299 return !memcmp(prefix, option, plen);
2300 }
2301
2302 static inline int selinux_option(char *option, int len)
2303 {
2304 return (match_prefix(CONTEXT_STR, sizeof(CONTEXT_STR)-1, option, len) ||
2305 match_prefix(FSCONTEXT_STR, sizeof(FSCONTEXT_STR)-1, option, len) ||
2306 match_prefix(DEFCONTEXT_STR, sizeof(DEFCONTEXT_STR)-1, option, len) ||
2307 match_prefix(ROOTCONTEXT_STR, sizeof(ROOTCONTEXT_STR)-1, option, len) ||
2308 match_prefix(LABELSUPP_STR, sizeof(LABELSUPP_STR)-1, option, len));
2309 }
2310
2311 static inline void take_option(char **to, char *from, int *first, int len)
2312 {
2313 if (!*first) {
2314 **to = ',';
2315 *to += 1;
2316 } else
2317 *first = 0;
2318 memcpy(*to, from, len);
2319 *to += len;
2320 }
2321
2322 static inline void take_selinux_option(char **to, char *from, int *first,
2323 int len)
2324 {
2325 int current_size = 0;
2326
2327 if (!*first) {
2328 **to = '|';
2329 *to += 1;
2330 } else
2331 *first = 0;
2332
2333 while (current_size < len) {
2334 if (*from != '"') {
2335 **to = *from;
2336 *to += 1;
2337 }
2338 from += 1;
2339 current_size += 1;
2340 }
2341 }
2342
2343 static int selinux_sb_copy_data(char *orig, char *copy)
2344 {
2345 int fnosec, fsec, rc = 0;
2346 char *in_save, *in_curr, *in_end;
2347 char *sec_curr, *nosec_save, *nosec;
2348 int open_quote = 0;
2349
2350 in_curr = orig;
2351 sec_curr = copy;
2352
2353 nosec = (char *)get_zeroed_page(GFP_KERNEL);
2354 if (!nosec) {
2355 rc = -ENOMEM;
2356 goto out;
2357 }
2358
2359 nosec_save = nosec;
2360 fnosec = fsec = 1;
2361 in_save = in_end = orig;
2362
2363 do {
2364 if (*in_end == '"')
2365 open_quote = !open_quote;
2366 if ((*in_end == ',' && open_quote == 0) ||
2367 *in_end == '\0') {
2368 int len = in_end - in_curr;
2369
2370 if (selinux_option(in_curr, len))
2371 take_selinux_option(&sec_curr, in_curr, &fsec, len);
2372 else
2373 take_option(&nosec, in_curr, &fnosec, len);
2374
2375 in_curr = in_end + 1;
2376 }
2377 } while (*in_end++);
2378
2379 strcpy(in_save, nosec_save);
2380 free_page((unsigned long)nosec_save);
2381 out:
2382 return rc;
2383 }
2384
2385 static int selinux_sb_remount(struct super_block *sb, void *data)
2386 {
2387 int rc, i, *flags;
2388 struct security_mnt_opts opts;
2389 char *secdata, **mount_options;
2390 struct superblock_security_struct *sbsec = sb->s_security;
2391
2392 if (!(sbsec->flags & SE_SBINITIALIZED))
2393 return 0;
2394
2395 if (!data)
2396 return 0;
2397
2398 if (sb->s_type->fs_flags & FS_BINARY_MOUNTDATA)
2399 return 0;
2400
2401 security_init_mnt_opts(&opts);
2402 secdata = alloc_secdata();
2403 if (!secdata)
2404 return -ENOMEM;
2405 rc = selinux_sb_copy_data(data, secdata);
2406 if (rc)
2407 goto out_free_secdata;
2408
2409 rc = selinux_parse_opts_str(secdata, &opts);
2410 if (rc)
2411 goto out_free_secdata;
2412
2413 mount_options = opts.mnt_opts;
2414 flags = opts.mnt_opts_flags;
2415
2416 for (i = 0; i < opts.num_mnt_opts; i++) {
2417 u32 sid;
2418 size_t len;
2419
2420 if (flags[i] == SE_SBLABELSUPP)
2421 continue;
2422 len = strlen(mount_options[i]);
2423 rc = security_context_to_sid(mount_options[i], len, &sid);
2424 if (rc) {
2425 printk(KERN_WARNING "SELinux: security_context_to_sid"
2426 "(%s) failed for (dev %s, type %s) errno=%d\n",
2427 mount_options[i], sb->s_id, sb->s_type->name, rc);
2428 goto out_free_opts;
2429 }
2430 rc = -EINVAL;
2431 switch (flags[i]) {
2432 case FSCONTEXT_MNT:
2433 if (bad_option(sbsec, FSCONTEXT_MNT, sbsec->sid, sid))
2434 goto out_bad_option;
2435 break;
2436 case CONTEXT_MNT:
2437 if (bad_option(sbsec, CONTEXT_MNT, sbsec->mntpoint_sid, sid))
2438 goto out_bad_option;
2439 break;
2440 case ROOTCONTEXT_MNT: {
2441 struct inode_security_struct *root_isec;
2442 root_isec = sb->s_root->d_inode->i_security;
2443
2444 if (bad_option(sbsec, ROOTCONTEXT_MNT, root_isec->sid, sid))
2445 goto out_bad_option;
2446 break;
2447 }
2448 case DEFCONTEXT_MNT:
2449 if (bad_option(sbsec, DEFCONTEXT_MNT, sbsec->def_sid, sid))
2450 goto out_bad_option;
2451 break;
2452 default:
2453 goto out_free_opts;
2454 }
2455 }
2456
2457 rc = 0;
2458 out_free_opts:
2459 security_free_mnt_opts(&opts);
2460 out_free_secdata:
2461 free_secdata(secdata);
2462 return rc;
2463 out_bad_option:
2464 printk(KERN_WARNING "SELinux: unable to change security options "
2465 "during remount (dev %s, type=%s)\n", sb->s_id,
2466 sb->s_type->name);
2467 goto out_free_opts;
2468 }
2469
2470 static int selinux_sb_kern_mount(struct super_block *sb, int flags, void *data)
2471 {
2472 const struct cred *cred = current_cred();
2473 struct common_audit_data ad;
2474 int rc;
2475
2476 rc = superblock_doinit(sb, data);
2477 if (rc)
2478 return rc;
2479
2480 /* Allow all mounts performed by the kernel */
2481 if (flags & MS_KERNMOUNT)
2482 return 0;
2483
2484 COMMON_AUDIT_DATA_INIT(&ad, DENTRY);
2485 ad.u.dentry = sb->s_root;
2486 return superblock_has_perm(cred, sb, FILESYSTEM__MOUNT, &ad);
2487 }
2488
2489 static int selinux_sb_statfs(struct dentry *dentry)
2490 {
2491 const struct cred *cred = current_cred();
2492 struct common_audit_data ad;
2493
2494 COMMON_AUDIT_DATA_INIT(&ad, DENTRY);
2495 ad.u.dentry = dentry->d_sb->s_root;
2496 return superblock_has_perm(cred, dentry->d_sb, FILESYSTEM__GETATTR, &ad);
2497 }
2498
2499 static int selinux_mount(char *dev_name,
2500 struct path *path,
2501 char *type,
2502 unsigned long flags,
2503 void *data)
2504 {
2505 const struct cred *cred = current_cred();
2506
2507 if (flags & MS_REMOUNT)
2508 return superblock_has_perm(cred, path->dentry->d_sb,
2509 FILESYSTEM__REMOUNT, NULL);
2510 else
2511 return path_has_perm(cred, path, FILE__MOUNTON);
2512 }
2513
2514 static int selinux_umount(struct vfsmount *mnt, int flags)
2515 {
2516 const struct cred *cred = current_cred();
2517
2518 return superblock_has_perm(cred, mnt->mnt_sb,
2519 FILESYSTEM__UNMOUNT, NULL);
2520 }
2521
2522 /* inode security operations */
2523
2524 static int selinux_inode_alloc_security(struct inode *inode)
2525 {
2526 return inode_alloc_security(inode);
2527 }
2528
2529 static void selinux_inode_free_security(struct inode *inode)
2530 {
2531 inode_free_security(inode);
2532 }
2533
2534 static int selinux_inode_init_security(struct inode *inode, struct inode *dir,
2535 const struct qstr *qstr, char **name,
2536 void **value, size_t *len)
2537 {
2538 const struct task_security_struct *tsec = current_security();
2539 struct inode_security_struct *dsec;
2540 struct superblock_security_struct *sbsec;
2541 u32 sid, newsid, clen;
2542 int rc;
2543 char *namep = NULL, *context;
2544
2545 dsec = dir->i_security;
2546 sbsec = dir->i_sb->s_security;
2547
2548 sid = tsec->sid;
2549 newsid = tsec->create_sid;
2550
2551 if ((sbsec->flags & SE_SBINITIALIZED) &&
2552 (sbsec->behavior == SECURITY_FS_USE_MNTPOINT))
2553 newsid = sbsec->mntpoint_sid;
2554 else if (!newsid || !(sbsec->flags & SE_SBLABELSUPP)) {
2555 rc = security_transition_sid(sid, dsec->sid,
2556 inode_mode_to_security_class(inode->i_mode),
2557 qstr, &newsid);
2558 if (rc) {
2559 printk(KERN_WARNING "%s: "
2560 "security_transition_sid failed, rc=%d (dev=%s "
2561 "ino=%ld)\n",
2562 __func__,
2563 -rc, inode->i_sb->s_id, inode->i_ino);
2564 return rc;
2565 }
2566 }
2567
2568 /* Possibly defer initialization to selinux_complete_init. */
2569 if (sbsec->flags & SE_SBINITIALIZED) {
2570 struct inode_security_struct *isec = inode->i_security;
2571 isec->sclass = inode_mode_to_security_class(inode->i_mode);
2572 isec->sid = newsid;
2573 isec->initialized = 1;
2574 }
2575
2576 if (!ss_initialized || !(sbsec->flags & SE_SBLABELSUPP))
2577 return -EOPNOTSUPP;
2578
2579 if (name) {
2580 namep = kstrdup(XATTR_SELINUX_SUFFIX, GFP_NOFS);
2581 if (!namep)
2582 return -ENOMEM;
2583 *name = namep;
2584 }
2585
2586 if (value && len) {
2587 rc = security_sid_to_context_force(newsid, &context, &clen);
2588 if (rc) {
2589 kfree(namep);
2590 return rc;
2591 }
2592 *value = context;
2593 *len = clen;
2594 }
2595
2596 return 0;
2597 }
2598
2599 static int selinux_inode_create(struct inode *dir, struct dentry *dentry, umode_t mode)
2600 {
2601 return may_create(dir, dentry, SECCLASS_FILE);
2602 }
2603
2604 static int selinux_inode_link(struct dentry *old_dentry, struct inode *dir, struct dentry *new_dentry)
2605 {
2606 return may_link(dir, old_dentry, MAY_LINK);
2607 }
2608
2609 static int selinux_inode_unlink(struct inode *dir, struct dentry *dentry)
2610 {
2611 return may_link(dir, dentry, MAY_UNLINK);
2612 }
2613
2614 static int selinux_inode_symlink(struct inode *dir, struct dentry *dentry, const char *name)
2615 {
2616 return may_create(dir, dentry, SECCLASS_LNK_FILE);
2617 }
2618
2619 static int selinux_inode_mkdir(struct inode *dir, struct dentry *dentry, umode_t mask)
2620 {
2621 return may_create(dir, dentry, SECCLASS_DIR);
2622 }
2623
2624 static int selinux_inode_rmdir(struct inode *dir, struct dentry *dentry)
2625 {
2626 return may_link(dir, dentry, MAY_RMDIR);
2627 }
2628
2629 static int selinux_inode_mknod(struct inode *dir, struct dentry *dentry, umode_t mode, dev_t dev)
2630 {
2631 return may_create(dir, dentry, inode_mode_to_security_class(mode));
2632 }
2633
2634 static int selinux_inode_rename(struct inode *old_inode, struct dentry *old_dentry,
2635 struct inode *new_inode, struct dentry *new_dentry)
2636 {
2637 return may_rename(old_inode, old_dentry, new_inode, new_dentry);
2638 }
2639
2640 static int selinux_inode_readlink(struct dentry *dentry)
2641 {
2642 const struct cred *cred = current_cred();
2643
2644 return dentry_has_perm(cred, dentry, FILE__READ);
2645 }
2646
2647 static int selinux_inode_follow_link(struct dentry *dentry, struct nameidata *nameidata)
2648 {
2649 const struct cred *cred = current_cred();
2650
2651 return dentry_has_perm(cred, dentry, FILE__READ);
2652 }
2653
2654 static int selinux_inode_permission(struct inode *inode, int mask)
2655 {
2656 const struct cred *cred = current_cred();
2657 struct common_audit_data ad;
2658 u32 perms;
2659 bool from_access;
2660 unsigned flags = mask & MAY_NOT_BLOCK;
2661
2662 from_access = mask & MAY_ACCESS;
2663 mask &= (MAY_READ|MAY_WRITE|MAY_EXEC|MAY_APPEND);
2664
2665 /* No permission to check. Existence test. */
2666 if (!mask)
2667 return 0;
2668
2669 COMMON_AUDIT_DATA_INIT(&ad, INODE);
2670 ad.u.inode = inode;
2671
2672 if (from_access)
2673 ad.selinux_audit_data.auditdeny |= FILE__AUDIT_ACCESS;
2674
2675 perms = file_mask_to_av(inode->i_mode, mask);
2676
2677 return inode_has_perm(cred, inode, perms, &ad, flags);
2678 }
2679
2680 static int selinux_inode_setattr(struct dentry *dentry, struct iattr *iattr)
2681 {
2682 const struct cred *cred = current_cred();
2683 unsigned int ia_valid = iattr->ia_valid;
2684
2685 /* ATTR_FORCE is just used for ATTR_KILL_S[UG]ID. */
2686 if (ia_valid & ATTR_FORCE) {
2687 ia_valid &= ~(ATTR_KILL_SUID | ATTR_KILL_SGID | ATTR_MODE |
2688 ATTR_FORCE);
2689 if (!ia_valid)
2690 return 0;
2691 }
2692
2693 if (ia_valid & (ATTR_MODE | ATTR_UID | ATTR_GID |
2694 ATTR_ATIME_SET | ATTR_MTIME_SET | ATTR_TIMES_SET))
2695 return dentry_has_perm(cred, dentry, FILE__SETATTR);
2696
2697 return dentry_has_perm(cred, dentry, FILE__WRITE);
2698 }
2699
2700 static int selinux_inode_getattr(struct vfsmount *mnt, struct dentry *dentry)
2701 {
2702 const struct cred *cred = current_cred();
2703 struct path path;
2704
2705 path.dentry = dentry;
2706 path.mnt = mnt;
2707
2708 return path_has_perm(cred, &path, FILE__GETATTR);
2709 }
2710
2711 static int selinux_inode_setotherxattr(struct dentry *dentry, const char *name)
2712 {
2713 const struct cred *cred = current_cred();
2714
2715 if (!strncmp(name, XATTR_SECURITY_PREFIX,
2716 sizeof XATTR_SECURITY_PREFIX - 1)) {
2717 if (!strcmp(name, XATTR_NAME_CAPS)) {
2718 if (!capable(CAP_SETFCAP))
2719 return -EPERM;
2720 } else if (!capable(CAP_SYS_ADMIN)) {
2721 /* A different attribute in the security namespace.
2722 Restrict to administrator. */
2723 return -EPERM;
2724 }
2725 }
2726
2727 /* Not an attribute we recognize, so just check the
2728 ordinary setattr permission. */
2729 return dentry_has_perm(cred, dentry, FILE__SETATTR);
2730 }
2731
2732 static int selinux_inode_setxattr(struct dentry *dentry, const char *name,
2733 const void *value, size_t size, int flags)
2734 {
2735 struct inode *inode = dentry->d_inode;
2736 struct inode_security_struct *isec = inode->i_security;
2737 struct superblock_security_struct *sbsec;
2738 struct common_audit_data ad;
2739 u32 newsid, sid = current_sid();
2740 int rc = 0;
2741
2742 if (strcmp(name, XATTR_NAME_SELINUX))
2743 return selinux_inode_setotherxattr(dentry, name);
2744
2745 sbsec = inode->i_sb->s_security;
2746 if (!(sbsec->flags & SE_SBLABELSUPP))
2747 return -EOPNOTSUPP;
2748
2749 if (!inode_owner_or_capable(inode))
2750 return -EPERM;
2751
2752 COMMON_AUDIT_DATA_INIT(&ad, DENTRY);
2753 ad.u.dentry = dentry;
2754
2755 rc = avc_has_perm(sid, isec->sid, isec->sclass,
2756 FILE__RELABELFROM, &ad);
2757 if (rc)
2758 return rc;
2759
2760 rc = security_context_to_sid(value, size, &newsid);
2761 if (rc == -EINVAL) {
2762 if (!capable(CAP_MAC_ADMIN))
2763 return rc;
2764 rc = security_context_to_sid_force(value, size, &newsid);
2765 }
2766 if (rc)
2767 return rc;
2768
2769 rc = avc_has_perm(sid, newsid, isec->sclass,
2770 FILE__RELABELTO, &ad);
2771 if (rc)
2772 return rc;
2773
2774 rc = security_validate_transition(isec->sid, newsid, sid,
2775 isec->sclass);
2776 if (rc)
2777 return rc;
2778
2779 return avc_has_perm(newsid,
2780 sbsec->sid,
2781 SECCLASS_FILESYSTEM,
2782 FILESYSTEM__ASSOCIATE,
2783 &ad);
2784 }
2785
2786 static void selinux_inode_post_setxattr(struct dentry *dentry, const char *name,
2787 const void *value, size_t size,
2788 int flags)
2789 {
2790 struct inode *inode = dentry->d_inode;
2791 struct inode_security_struct *isec = inode->i_security;
2792 u32 newsid;
2793 int rc;
2794
2795 if (strcmp(name, XATTR_NAME_SELINUX)) {
2796 /* Not an attribute we recognize, so nothing to do. */
2797 return;
2798 }
2799
2800 rc = security_context_to_sid_force(value, size, &newsid);
2801 if (rc) {
2802 printk(KERN_ERR "SELinux: unable to map context to SID"
2803 "for (%s, %lu), rc=%d\n",
2804 inode->i_sb->s_id, inode->i_ino, -rc);
2805 return;
2806 }
2807
2808 isec->sid = newsid;
2809 return;
2810 }
2811
2812 static int selinux_inode_getxattr(struct dentry *dentry, const char *name)
2813 {
2814 const struct cred *cred = current_cred();
2815
2816 return dentry_has_perm(cred, dentry, FILE__GETATTR);
2817 }
2818
2819 static int selinux_inode_listxattr(struct dentry *dentry)
2820 {
2821 const struct cred *cred = current_cred();
2822
2823 return dentry_has_perm(cred, dentry, FILE__GETATTR);
2824 }
2825
2826 static int selinux_inode_removexattr(struct dentry *dentry, const char *name)
2827 {
2828 if (strcmp(name, XATTR_NAME_SELINUX))
2829 return selinux_inode_setotherxattr(dentry, name);
2830
2831 /* No one is allowed to remove a SELinux security label.
2832 You can change the label, but all data must be labeled. */
2833 return -EACCES;
2834 }
2835
2836 /*
2837 * Copy the inode security context value to the user.
2838 *
2839 * Permission check is handled by selinux_inode_getxattr hook.
2840 */
2841 static int selinux_inode_getsecurity(const struct inode *inode, const char *name, void **buffer, bool alloc)
2842 {
2843 u32 size;
2844 int error;
2845 char *context = NULL;
2846 struct inode_security_struct *isec = inode->i_security;
2847
2848 if (strcmp(name, XATTR_SELINUX_SUFFIX))
2849 return -EOPNOTSUPP;
2850
2851 /*
2852 * If the caller has CAP_MAC_ADMIN, then get the raw context
2853 * value even if it is not defined by current policy; otherwise,
2854 * use the in-core value under current policy.
2855 * Use the non-auditing forms of the permission checks since
2856 * getxattr may be called by unprivileged processes commonly
2857 * and lack of permission just means that we fall back to the
2858 * in-core context value, not a denial.
2859 */
2860 error = selinux_capable(current_cred(), &init_user_ns, CAP_MAC_ADMIN,
2861 SECURITY_CAP_NOAUDIT);
2862 if (!error)
2863 error = security_sid_to_context_force(isec->sid, &context,
2864 &size);
2865 else
2866 error = security_sid_to_context(isec->sid, &context, &size);
2867 if (error)
2868 return error;
2869 error = size;
2870 if (alloc) {
2871 *buffer = context;
2872 goto out_nofree;
2873 }
2874 kfree(context);
2875 out_nofree:
2876 return error;
2877 }
2878
2879 static int selinux_inode_setsecurity(struct inode *inode, const char *name,
2880 const void *value, size_t size, int flags)
2881 {
2882 struct inode_security_struct *isec = inode->i_security;
2883 u32 newsid;
2884 int rc;
2885
2886 if (strcmp(name, XATTR_SELINUX_SUFFIX))
2887 return -EOPNOTSUPP;
2888
2889 if (!value || !size)
2890 return -EACCES;
2891
2892 rc = security_context_to_sid((void *)value, size, &newsid);
2893 if (rc)
2894 return rc;
2895
2896 isec->sid = newsid;
2897 isec->initialized = 1;
2898 return 0;
2899 }
2900
2901 static int selinux_inode_listsecurity(struct inode *inode, char *buffer, size_t buffer_size)
2902 {
2903 const int len = sizeof(XATTR_NAME_SELINUX);
2904 if (buffer && len <= buffer_size)
2905 memcpy(buffer, XATTR_NAME_SELINUX, len);
2906 return len;
2907 }
2908
2909 static void selinux_inode_getsecid(const struct inode *inode, u32 *secid)
2910 {
2911 struct inode_security_struct *isec = inode->i_security;
2912 *secid = isec->sid;
2913 }
2914
2915 /* file security operations */
2916
2917 static int selinux_revalidate_file_permission(struct file *file, int mask)
2918 {
2919 const struct cred *cred = current_cred();
2920 struct inode *inode = file->f_path.dentry->d_inode;
2921
2922 /* file_mask_to_av won't add FILE__WRITE if MAY_APPEND is set */
2923 if ((file->f_flags & O_APPEND) && (mask & MAY_WRITE))
2924 mask |= MAY_APPEND;
2925
2926 return file_has_perm(cred, file,
2927 file_mask_to_av(inode->i_mode, mask));
2928 }
2929
2930 static int selinux_file_permission(struct file *file, int mask)
2931 {
2932 struct inode *inode = file->f_path.dentry->d_inode;
2933 struct file_security_struct *fsec = file->f_security;
2934 struct inode_security_struct *isec = inode->i_security;
2935 u32 sid = current_sid();
2936
2937 if (!mask)
2938 /* No permission to check. Existence test. */
2939 return 0;
2940
2941 if (sid == fsec->sid && fsec->isid == isec->sid &&
2942 fsec->pseqno == avc_policy_seqno())
2943 /* No change since dentry_open check. */
2944 return 0;
2945
2946 return selinux_revalidate_file_permission(file, mask);
2947 }
2948
2949 static int selinux_file_alloc_security(struct file *file)
2950 {
2951 return file_alloc_security(file);
2952 }
2953
2954 static void selinux_file_free_security(struct file *file)
2955 {
2956 file_free_security(file);
2957 }
2958
2959 static int selinux_file_ioctl(struct file *file, unsigned int cmd,
2960 unsigned long arg)
2961 {
2962 const struct cred *cred = current_cred();
2963 int error = 0;
2964
2965 switch (cmd) {
2966 case FIONREAD:
2967 /* fall through */
2968 case FIBMAP:
2969 /* fall through */
2970 case FIGETBSZ:
2971 /* fall through */
2972 case EXT2_IOC_GETFLAGS:
2973 /* fall through */
2974 case EXT2_IOC_GETVERSION:
2975 error = file_has_perm(cred, file, FILE__GETATTR);
2976 break;
2977
2978 case EXT2_IOC_SETFLAGS:
2979 /* fall through */
2980 case EXT2_IOC_SETVERSION:
2981 error = file_has_perm(cred, file, FILE__SETATTR);
2982 break;
2983
2984 /* sys_ioctl() checks */
2985 case FIONBIO:
2986 /* fall through */
2987 case FIOASYNC:
2988 error = file_has_perm(cred, file, 0);
2989 break;
2990
2991 case KDSKBENT:
2992 case KDSKBSENT:
2993 error = cred_has_capability(cred, CAP_SYS_TTY_CONFIG,
2994 SECURITY_CAP_AUDIT);
2995 break;
2996
2997 /* default case assumes that the command will go
2998 * to the file's ioctl() function.
2999 */
3000 default:
3001 error = file_has_perm(cred, file, FILE__IOCTL);
3002 }
3003 return error;
3004 }
3005
3006 static int default_noexec;
3007
3008 static int file_map_prot_check(struct file *file, unsigned long prot, int shared)
3009 {
3010 const struct cred *cred = current_cred();
3011 int rc = 0;
3012
3013 if (default_noexec &&
3014 (prot & PROT_EXEC) && (!file || (!shared && (prot & PROT_WRITE)))) {
3015 /*
3016 * We are making executable an anonymous mapping or a
3017 * private file mapping that will also be writable.
3018 * This has an additional check.
3019 */
3020 rc = cred_has_perm(cred, cred, PROCESS__EXECMEM);
3021 if (rc)
3022 goto error;
3023 }
3024
3025 if (file) {
3026 /* read access is always possible with a mapping */
3027 u32 av = FILE__READ;
3028
3029 /* write access only matters if the mapping is shared */
3030 if (shared && (prot & PROT_WRITE))
3031 av |= FILE__WRITE;
3032
3033 if (prot & PROT_EXEC)
3034 av |= FILE__EXECUTE;
3035
3036 return file_has_perm(cred, file, av);
3037 }
3038
3039 error:
3040 return rc;
3041 }
3042
3043 static int selinux_file_mmap(struct file *file, unsigned long reqprot,
3044 unsigned long prot, unsigned long flags,
3045 unsigned long addr, unsigned long addr_only)
3046 {
3047 int rc = 0;
3048 u32 sid = current_sid();
3049
3050 /*
3051 * notice that we are intentionally putting the SELinux check before
3052 * the secondary cap_file_mmap check. This is such a likely attempt
3053 * at bad behaviour/exploit that we always want to get the AVC, even
3054 * if DAC would have also denied the operation.
3055 */
3056 if (addr < CONFIG_LSM_MMAP_MIN_ADDR) {
3057 rc = avc_has_perm(sid, sid, SECCLASS_MEMPROTECT,
3058 MEMPROTECT__MMAP_ZERO, NULL);
3059 if (rc)
3060 return rc;
3061 }
3062
3063 /* do DAC check on address space usage */
3064 rc = cap_file_mmap(file, reqprot, prot, flags, addr, addr_only);
3065 if (rc || addr_only)
3066 return rc;
3067
3068 if (selinux_checkreqprot)
3069 prot = reqprot;
3070
3071 return file_map_prot_check(file, prot,
3072 (flags & MAP_TYPE) == MAP_SHARED);
3073 }
3074
3075 static int selinux_file_mprotect(struct vm_area_struct *vma,
3076 unsigned long reqprot,
3077 unsigned long prot)
3078 {
3079 const struct cred *cred = current_cred();
3080
3081 if (selinux_checkreqprot)
3082 prot = reqprot;
3083
3084 if (default_noexec &&
3085 (prot & PROT_EXEC) && !(vma->vm_flags & VM_EXEC)) {
3086 int rc = 0;
3087 if (vma->vm_start >= vma->vm_mm->start_brk &&
3088 vma->vm_end <= vma->vm_mm->brk) {
3089 rc = cred_has_perm(cred, cred, PROCESS__EXECHEAP);
3090 } else if (!vma->vm_file &&
3091 vma->vm_start <= vma->vm_mm->start_stack &&
3092 vma->vm_end >= vma->vm_mm->start_stack) {
3093 rc = current_has_perm(current, PROCESS__EXECSTACK);
3094 } else if (vma->vm_file && vma->anon_vma) {
3095 /*
3096 * We are making executable a file mapping that has
3097 * had some COW done. Since pages might have been
3098 * written, check ability to execute the possibly
3099 * modified content. This typically should only
3100 * occur for text relocations.
3101 */
3102 rc = file_has_perm(cred, vma->vm_file, FILE__EXECMOD);
3103 }
3104 if (rc)
3105 return rc;
3106 }
3107
3108 return file_map_prot_check(vma->vm_file, prot, vma->vm_flags&VM_SHARED);
3109 }
3110
3111 static int selinux_file_lock(struct file *file, unsigned int cmd)
3112 {
3113 const struct cred *cred = current_cred();
3114
3115 return file_has_perm(cred, file, FILE__LOCK);
3116 }
3117
3118 static int selinux_file_fcntl(struct file *file, unsigned int cmd,
3119 unsigned long arg)
3120 {
3121 const struct cred *cred = current_cred();
3122 int err = 0;
3123
3124 switch (cmd) {
3125 case F_SETFL:
3126 if (!file->f_path.dentry || !file->f_path.dentry->d_inode) {
3127 err = -EINVAL;
3128 break;
3129 }
3130
3131 if ((file->f_flags & O_APPEND) && !(arg & O_APPEND)) {
3132 err = file_has_perm(cred, file, FILE__WRITE);
3133 break;
3134 }
3135 /* fall through */
3136 case F_SETOWN:
3137 case F_SETSIG:
3138 case F_GETFL:
3139 case F_GETOWN:
3140 case F_GETSIG:
3141 /* Just check FD__USE permission */
3142 err = file_has_perm(cred, file, 0);
3143 break;
3144 case F_GETLK:
3145 case F_SETLK:
3146 case F_SETLKW:
3147 #if BITS_PER_LONG == 32
3148 case F_GETLK64:
3149 case F_SETLK64:
3150 case F_SETLKW64:
3151 #endif
3152 if (!file->f_path.dentry || !file->f_path.dentry->d_inode) {
3153 err = -EINVAL;
3154 break;
3155 }
3156 err = file_has_perm(cred, file, FILE__LOCK);
3157 break;
3158 }
3159
3160 return err;
3161 }
3162
3163 static int selinux_file_set_fowner(struct file *file)
3164 {
3165 struct file_security_struct *fsec;
3166
3167 fsec = file->f_security;
3168 fsec->fown_sid = current_sid();
3169
3170 return 0;
3171 }
3172
3173 static int selinux_file_send_sigiotask(struct task_struct *tsk,
3174 struct fown_struct *fown, int signum)
3175 {
3176 struct file *file;
3177 u32 sid = task_sid(tsk);
3178 u32 perm;
3179 struct file_security_struct *fsec;
3180
3181 /* struct fown_struct is never outside the context of a struct file */
3182 file = container_of(fown, struct file, f_owner);
3183
3184 fsec = file->f_security;
3185
3186 if (!signum)
3187 perm = signal_to_av(SIGIO); /* as per send_sigio_to_task */
3188 else
3189 perm = signal_to_av(signum);
3190
3191 return avc_has_perm(fsec->fown_sid, sid,
3192 SECCLASS_PROCESS, perm, NULL);
3193 }
3194
3195 static int selinux_file_receive(struct file *file)
3196 {
3197 const struct cred *cred = current_cred();
3198
3199 return file_has_perm(cred, file, file_to_av(file));
3200 }
3201
3202 static int selinux_dentry_open(struct file *file, const struct cred *cred)
3203 {
3204 struct file_security_struct *fsec;
3205 struct inode *inode;
3206 struct inode_security_struct *isec;
3207
3208 inode = file->f_path.dentry->d_inode;
3209 fsec = file->f_security;
3210 isec = inode->i_security;
3211 /*
3212 * Save inode label and policy sequence number
3213 * at open-time so that selinux_file_permission
3214 * can determine whether revalidation is necessary.
3215 * Task label is already saved in the file security
3216 * struct as its SID.
3217 */
3218 fsec->isid = isec->sid;
3219 fsec->pseqno = avc_policy_seqno();
3220 /*
3221 * Since the inode label or policy seqno may have changed
3222 * between the selinux_inode_permission check and the saving
3223 * of state above, recheck that access is still permitted.
3224 * Otherwise, access might never be revalidated against the
3225 * new inode label or new policy.
3226 * This check is not redundant - do not remove.
3227 */
3228 return inode_has_perm_noadp(cred, inode, open_file_to_av(file), 0);
3229 }
3230
3231 /* task security operations */
3232
3233 static int selinux_task_create(unsigned long clone_flags)
3234 {
3235 return current_has_perm(current, PROCESS__FORK);
3236 }
3237
3238 /*
3239 * allocate the SELinux part of blank credentials
3240 */
3241 static int selinux_cred_alloc_blank(struct cred *cred, gfp_t gfp)
3242 {
3243 struct task_security_struct *tsec;
3244
3245 tsec = kzalloc(sizeof(struct task_security_struct), gfp);
3246 if (!tsec)
3247 return -ENOMEM;
3248
3249 cred->security = tsec;
3250 return 0;
3251 }
3252
3253 /*
3254 * detach and free the LSM part of a set of credentials
3255 */
3256 static void selinux_cred_free(struct cred *cred)
3257 {
3258 struct task_security_struct *tsec = cred->security;
3259
3260 /*
3261 * cred->security == NULL if security_cred_alloc_blank() or
3262 * security_prepare_creds() returned an error.
3263 */
3264 BUG_ON(cred->security && (unsigned long) cred->security < PAGE_SIZE);
3265 cred->security = (void *) 0x7UL;
3266 kfree(tsec);
3267 }
3268
3269 /*
3270 * prepare a new set of credentials for modification
3271 */
3272 static int selinux_cred_prepare(struct cred *new, const struct cred *old,
3273 gfp_t gfp)
3274 {
3275 const struct task_security_struct *old_tsec;
3276 struct task_security_struct *tsec;
3277
3278 old_tsec = old->security;
3279
3280 tsec = kmemdup(old_tsec, sizeof(struct task_security_struct), gfp);
3281 if (!tsec)
3282 return -ENOMEM;
3283
3284 new->security = tsec;
3285 return 0;
3286 }
3287
3288 /*
3289 * transfer the SELinux data to a blank set of creds
3290 */
3291 static void selinux_cred_transfer(struct cred *new, const struct cred *old)
3292 {
3293 const struct task_security_struct *old_tsec = old->security;
3294 struct task_security_struct *tsec = new->security;
3295
3296 *tsec = *old_tsec;
3297 }
3298
3299 /*
3300 * set the security data for a kernel service
3301 * - all the creation contexts are set to unlabelled
3302 */
3303 static int selinux_kernel_act_as(struct cred *new, u32 secid)
3304 {
3305 struct task_security_struct *tsec = new->security;
3306 u32 sid = current_sid();
3307 int ret;
3308
3309 ret = avc_has_perm(sid, secid,
3310 SECCLASS_KERNEL_SERVICE,
3311 KERNEL_SERVICE__USE_AS_OVERRIDE,
3312 NULL);
3313 if (ret == 0) {
3314 tsec->sid = secid;
3315 tsec->create_sid = 0;
3316 tsec->keycreate_sid = 0;
3317 tsec->sockcreate_sid = 0;
3318 }
3319 return ret;
3320 }
3321
3322 /*
3323 * set the file creation context in a security record to the same as the
3324 * objective context of the specified inode
3325 */
3326 static int selinux_kernel_create_files_as(struct cred *new, struct inode *inode)
3327 {
3328 struct inode_security_struct *isec = inode->i_security;
3329 struct task_security_struct *tsec = new->security;
3330 u32 sid = current_sid();
3331 int ret;
3332
3333 ret = avc_has_perm(sid, isec->sid,
3334 SECCLASS_KERNEL_SERVICE,
3335 KERNEL_SERVICE__CREATE_FILES_AS,
3336 NULL);
3337
3338 if (ret == 0)
3339 tsec->create_sid = isec->sid;
3340 return ret;
3341 }
3342
3343 static int selinux_kernel_module_request(char *kmod_name)
3344 {
3345 u32 sid;
3346 struct common_audit_data ad;
3347
3348 sid = task_sid(current);
3349
3350 COMMON_AUDIT_DATA_INIT(&ad, KMOD);
3351 ad.u.kmod_name = kmod_name;
3352
3353 return avc_has_perm(sid, SECINITSID_KERNEL, SECCLASS_SYSTEM,
3354 SYSTEM__MODULE_REQUEST, &ad);
3355 }
3356
3357 static int selinux_task_setpgid(struct task_struct *p, pid_t pgid)
3358 {
3359 return current_has_perm(p, PROCESS__SETPGID);
3360 }
3361
3362 static int selinux_task_getpgid(struct task_struct *p)
3363 {
3364 return current_has_perm(p, PROCESS__GETPGID);
3365 }
3366
3367 static int selinux_task_getsid(struct task_struct *p)
3368 {
3369 return current_has_perm(p, PROCESS__GETSESSION);
3370 }
3371
3372 static void selinux_task_getsecid(struct task_struct *p, u32 *secid)
3373 {
3374 *secid = task_sid(p);
3375 }
3376
3377 static int selinux_task_setnice(struct task_struct *p, int nice)
3378 {
3379 int rc;
3380
3381 rc = cap_task_setnice(p, nice);
3382 if (rc)
3383 return rc;
3384
3385 return current_has_perm(p, PROCESS__SETSCHED);
3386 }
3387
3388 static int selinux_task_setioprio(struct task_struct *p, int ioprio)
3389 {
3390 int rc;
3391
3392 rc = cap_task_setioprio(p, ioprio);
3393 if (rc)
3394 return rc;
3395
3396 return current_has_perm(p, PROCESS__SETSCHED);
3397 }
3398
3399 static int selinux_task_getioprio(struct task_struct *p)
3400 {
3401 return current_has_perm(p, PROCESS__GETSCHED);
3402 }
3403
3404 static int selinux_task_setrlimit(struct task_struct *p, unsigned int resource,
3405 struct rlimit *new_rlim)
3406 {
3407 struct rlimit *old_rlim = p->signal->rlim + resource;
3408
3409 /* Control the ability to change the hard limit (whether
3410 lowering or raising it), so that the hard limit can
3411 later be used as a safe reset point for the soft limit
3412 upon context transitions. See selinux_bprm_committing_creds. */
3413 if (old_rlim->rlim_max != new_rlim->rlim_max)
3414 return current_has_perm(p, PROCESS__SETRLIMIT);
3415
3416 return 0;
3417 }
3418
3419 static int selinux_task_setscheduler(struct task_struct *p)
3420 {
3421 int rc;
3422
3423 rc = cap_task_setscheduler(p);
3424 if (rc)
3425 return rc;
3426
3427 return current_has_perm(p, PROCESS__SETSCHED);
3428 }
3429
3430 static int selinux_task_getscheduler(struct task_struct *p)
3431 {
3432 return current_has_perm(p, PROCESS__GETSCHED);
3433 }
3434
3435 static int selinux_task_movememory(struct task_struct *p)
3436 {
3437 return current_has_perm(p, PROCESS__SETSCHED);
3438 }
3439
3440 static int selinux_task_kill(struct task_struct *p, struct siginfo *info,
3441 int sig, u32 secid)
3442 {
3443 u32 perm;
3444 int rc;
3445
3446 if (!sig)
3447 perm = PROCESS__SIGNULL; /* null signal; existence test */
3448 else
3449 perm = signal_to_av(sig);
3450 if (secid)
3451 rc = avc_has_perm(secid, task_sid(p),
3452 SECCLASS_PROCESS, perm, NULL);
3453 else
3454 rc = current_has_perm(p, perm);
3455 return rc;
3456 }
3457
3458 static int selinux_task_wait(struct task_struct *p)
3459 {
3460 return task_has_perm(p, current, PROCESS__SIGCHLD);
3461 }
3462
3463 static void selinux_task_to_inode(struct task_struct *p,
3464 struct inode *inode)
3465 {
3466 struct inode_security_struct *isec = inode->i_security;
3467 u32 sid = task_sid(p);
3468
3469 isec->sid = sid;
3470 isec->initialized = 1;
3471 }
3472
3473 /* Returns error only if unable to parse addresses */
3474 static int selinux_parse_skb_ipv4(struct sk_buff *skb,
3475 struct common_audit_data *ad, u8 *proto)
3476 {
3477 int offset, ihlen, ret = -EINVAL;
3478 struct iphdr _iph, *ih;
3479
3480 offset = skb_network_offset(skb);
3481 ih = skb_header_pointer(skb, offset, sizeof(_iph), &_iph);
3482 if (ih == NULL)
3483 goto out;
3484
3485 ihlen = ih->ihl * 4;
3486 if (ihlen < sizeof(_iph))
3487 goto out;
3488
3489 ad->u.net.v4info.saddr = ih->saddr;
3490 ad->u.net.v4info.daddr = ih->daddr;
3491 ret = 0;
3492
3493 if (proto)
3494 *proto = ih->protocol;
3495
3496 switch (ih->protocol) {
3497 case IPPROTO_TCP: {
3498 struct tcphdr _tcph, *th;
3499
3500 if (ntohs(ih->frag_off) & IP_OFFSET)
3501 break;
3502
3503 offset += ihlen;
3504 th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph);
3505 if (th == NULL)
3506 break;
3507
3508 ad->u.net.sport = th->source;
3509 ad->u.net.dport = th->dest;
3510 break;
3511 }
3512
3513 case IPPROTO_UDP: {
3514 struct udphdr _udph, *uh;
3515
3516 if (ntohs(ih->frag_off) & IP_OFFSET)
3517 break;
3518
3519 offset += ihlen;
3520 uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph);
3521 if (uh == NULL)
3522 break;
3523
3524 ad->u.net.sport = uh->source;
3525 ad->u.net.dport = uh->dest;
3526 break;
3527 }
3528
3529 case IPPROTO_DCCP: {
3530 struct dccp_hdr _dccph, *dh;
3531
3532 if (ntohs(ih->frag_off) & IP_OFFSET)
3533 break;
3534
3535 offset += ihlen;
3536 dh = skb_header_pointer(skb, offset, sizeof(_dccph), &_dccph);
3537 if (dh == NULL)
3538 break;
3539
3540 ad->u.net.sport = dh->dccph_sport;
3541 ad->u.net.dport = dh->dccph_dport;
3542 break;
3543 }
3544
3545 default:
3546 break;
3547 }
3548 out:
3549 return ret;
3550 }
3551
3552 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
3553
3554 /* Returns error only if unable to parse addresses */
3555 static int selinux_parse_skb_ipv6(struct sk_buff *skb,
3556 struct common_audit_data *ad, u8 *proto)
3557 {
3558 u8 nexthdr;
3559 int ret = -EINVAL, offset;
3560 struct ipv6hdr _ipv6h, *ip6;
3561 __be16 frag_off;
3562
3563 offset = skb_network_offset(skb);
3564 ip6 = skb_header_pointer(skb, offset, sizeof(_ipv6h), &_ipv6h);
3565 if (ip6 == NULL)
3566 goto out;
3567
3568 ad->u.net.v6info.saddr = ip6->saddr;
3569 ad->u.net.v6info.daddr = ip6->daddr;
3570 ret = 0;
3571
3572 nexthdr = ip6->nexthdr;
3573 offset += sizeof(_ipv6h);
3574 offset = ipv6_skip_exthdr(skb, offset, &nexthdr, &frag_off);
3575 if (offset < 0)
3576 goto out;
3577
3578 if (proto)
3579 *proto = nexthdr;
3580
3581 switch (nexthdr) {
3582 case IPPROTO_TCP: {
3583 struct tcphdr _tcph, *th;
3584
3585 th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph);
3586 if (th == NULL)
3587 break;
3588
3589 ad->u.net.sport = th->source;
3590 ad->u.net.dport = th->dest;
3591 break;
3592 }
3593
3594 case IPPROTO_UDP: {
3595 struct udphdr _udph, *uh;
3596
3597 uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph);
3598 if (uh == NULL)
3599 break;
3600
3601 ad->u.net.sport = uh->source;
3602 ad->u.net.dport = uh->dest;
3603 break;
3604 }
3605
3606 case IPPROTO_DCCP: {
3607 struct dccp_hdr _dccph, *dh;
3608
3609 dh = skb_header_pointer(skb, offset, sizeof(_dccph), &_dccph);
3610 if (dh == NULL)
3611 break;
3612
3613 ad->u.net.sport = dh->dccph_sport;
3614 ad->u.net.dport = dh->dccph_dport;
3615 break;
3616 }
3617
3618 /* includes fragments */
3619 default:
3620 break;
3621 }
3622 out:
3623 return ret;
3624 }
3625
3626 #endif /* IPV6 */
3627
3628 static int selinux_parse_skb(struct sk_buff *skb, struct common_audit_data *ad,
3629 char **_addrp, int src, u8 *proto)
3630 {
3631 char *addrp;
3632 int ret;
3633
3634 switch (ad->u.net.family) {
3635 case PF_INET:
3636 ret = selinux_parse_skb_ipv4(skb, ad, proto);
3637 if (ret)
3638 goto parse_error;
3639 addrp = (char *)(src ? &ad->u.net.v4info.saddr :
3640 &ad->u.net.v4info.daddr);
3641 goto okay;
3642
3643 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
3644 case PF_INET6:
3645 ret = selinux_parse_skb_ipv6(skb, ad, proto);
3646 if (ret)
3647 goto parse_error;
3648 addrp = (char *)(src ? &ad->u.net.v6info.saddr :
3649 &ad->u.net.v6info.daddr);
3650 goto okay;
3651 #endif /* IPV6 */
3652 default:
3653 addrp = NULL;
3654 goto okay;
3655 }
3656
3657 parse_error:
3658 printk(KERN_WARNING
3659 "SELinux: failure in selinux_parse_skb(),"
3660 " unable to parse packet\n");
3661 return ret;
3662
3663 okay:
3664 if (_addrp)
3665 *_addrp = addrp;
3666 return 0;
3667 }
3668
3669 /**
3670 * selinux_skb_peerlbl_sid - Determine the peer label of a packet
3671 * @skb: the packet
3672 * @family: protocol family
3673 * @sid: the packet's peer label SID
3674 *
3675 * Description:
3676 * Check the various different forms of network peer labeling and determine
3677 * the peer label/SID for the packet; most of the magic actually occurs in
3678 * the security server function security_net_peersid_cmp(). The function
3679 * returns zero if the value in @sid is valid (although it may be SECSID_NULL)
3680 * or -EACCES if @sid is invalid due to inconsistencies with the different
3681 * peer labels.
3682 *
3683 */
3684 static int selinux_skb_peerlbl_sid(struct sk_buff *skb, u16 family, u32 *sid)
3685 {
3686 int err;
3687 u32 xfrm_sid;
3688 u32 nlbl_sid;
3689 u32 nlbl_type;
3690
3691 selinux_skb_xfrm_sid(skb, &xfrm_sid);
3692 selinux_netlbl_skbuff_getsid(skb, family, &nlbl_type, &nlbl_sid);
3693
3694 err = security_net_peersid_resolve(nlbl_sid, nlbl_type, xfrm_sid, sid);
3695 if (unlikely(err)) {
3696 printk(KERN_WARNING
3697 "SELinux: failure in selinux_skb_peerlbl_sid(),"
3698 " unable to determine packet's peer label\n");
3699 return -EACCES;
3700 }
3701
3702 return 0;
3703 }
3704
3705 /* socket security operations */
3706
3707 static int socket_sockcreate_sid(const struct task_security_struct *tsec,
3708 u16 secclass, u32 *socksid)
3709 {
3710 if (tsec->sockcreate_sid > SECSID_NULL) {
3711 *socksid = tsec->sockcreate_sid;
3712 return 0;
3713 }
3714
3715 return security_transition_sid(tsec->sid, tsec->sid, secclass, NULL,
3716 socksid);
3717 }
3718
3719 static int sock_has_perm(struct task_struct *task, struct sock *sk, u32 perms)
3720 {
3721 struct sk_security_struct *sksec = sk->sk_security;
3722 struct common_audit_data ad;
3723 u32 tsid = task_sid(task);
3724
3725 if (sksec->sid == SECINITSID_KERNEL)
3726 return 0;
3727
3728 COMMON_AUDIT_DATA_INIT(&ad, NET);
3729 ad.u.net.sk = sk;
3730
3731 return avc_has_perm(tsid, sksec->sid, sksec->sclass, perms, &ad);
3732 }
3733
3734 static int selinux_socket_create(int family, int type,
3735 int protocol, int kern)
3736 {
3737 const struct task_security_struct *tsec = current_security();
3738 u32 newsid;
3739 u16 secclass;
3740 int rc;
3741
3742 if (kern)
3743 return 0;
3744
3745 secclass = socket_type_to_security_class(family, type, protocol);
3746 rc = socket_sockcreate_sid(tsec, secclass, &newsid);
3747 if (rc)
3748 return rc;
3749
3750 return avc_has_perm(tsec->sid, newsid, secclass, SOCKET__CREATE, NULL);
3751 }
3752
3753 static int selinux_socket_post_create(struct socket *sock, int family,
3754 int type, int protocol, int kern)
3755 {
3756 const struct task_security_struct *tsec = current_security();
3757 struct inode_security_struct *isec = SOCK_INODE(sock)->i_security;
3758 struct sk_security_struct *sksec;
3759 int err = 0;
3760
3761 isec->sclass = socket_type_to_security_class(family, type, protocol);
3762
3763 if (kern)
3764 isec->sid = SECINITSID_KERNEL;
3765 else {
3766 err = socket_sockcreate_sid(tsec, isec->sclass, &(isec->sid));
3767 if (err)
3768 return err;
3769 }
3770
3771 isec->initialized = 1;
3772
3773 if (sock->sk) {
3774 sksec = sock->sk->sk_security;
3775 sksec->sid = isec->sid;
3776 sksec->sclass = isec->sclass;
3777 err = selinux_netlbl_socket_post_create(sock->sk, family);
3778 }
3779
3780 return err;
3781 }
3782
3783 /* Range of port numbers used to automatically bind.
3784 Need to determine whether we should perform a name_bind
3785 permission check between the socket and the port number. */
3786
3787 static int selinux_socket_bind(struct socket *sock, struct sockaddr *address, int addrlen)
3788 {
3789 struct sock *sk = sock->sk;
3790 u16 family;
3791 int err;
3792
3793 err = sock_has_perm(current, sk, SOCKET__BIND);
3794 if (err)
3795 goto out;
3796
3797 /*
3798 * If PF_INET or PF_INET6, check name_bind permission for the port.
3799 * Multiple address binding for SCTP is not supported yet: we just
3800 * check the first address now.
3801 */
3802 family = sk->sk_family;
3803 if (family == PF_INET || family == PF_INET6) {
3804 char *addrp;
3805 struct sk_security_struct *sksec = sk->sk_security;
3806 struct common_audit_data ad;
3807 struct sockaddr_in *addr4 = NULL;
3808 struct sockaddr_in6 *addr6 = NULL;
3809 unsigned short snum;
3810 u32 sid, node_perm;
3811
3812 if (family == PF_INET) {
3813 addr4 = (struct sockaddr_in *)address;
3814 snum = ntohs(addr4->sin_port);
3815 addrp = (char *)&addr4->sin_addr.s_addr;
3816 } else {
3817 addr6 = (struct sockaddr_in6 *)address;
3818 snum = ntohs(addr6->sin6_port);
3819 addrp = (char *)&addr6->sin6_addr.s6_addr;
3820 }
3821
3822 if (snum) {
3823 int low, high;
3824
3825 inet_get_local_port_range(&low, &high);
3826
3827 if (snum < max(PROT_SOCK, low) || snum > high) {
3828 err = sel_netport_sid(sk->sk_protocol,
3829 snum, &sid);
3830 if (err)
3831 goto out;
3832 COMMON_AUDIT_DATA_INIT(&ad, NET);
3833 ad.u.net.sport = htons(snum);
3834 ad.u.net.family = family;
3835 err = avc_has_perm(sksec->sid, sid,
3836 sksec->sclass,
3837 SOCKET__NAME_BIND, &ad);
3838 if (err)
3839 goto out;
3840 }
3841 }
3842
3843 switch (sksec->sclass) {
3844 case SECCLASS_TCP_SOCKET:
3845 node_perm = TCP_SOCKET__NODE_BIND;
3846 break;
3847
3848 case SECCLASS_UDP_SOCKET:
3849 node_perm = UDP_SOCKET__NODE_BIND;
3850 break;
3851
3852 case SECCLASS_DCCP_SOCKET:
3853 node_perm = DCCP_SOCKET__NODE_BIND;
3854 break;
3855
3856 default:
3857 node_perm = RAWIP_SOCKET__NODE_BIND;
3858 break;
3859 }
3860
3861 err = sel_netnode_sid(addrp, family, &sid);
3862 if (err)
3863 goto out;
3864
3865 COMMON_AUDIT_DATA_INIT(&ad, NET);
3866 ad.u.net.sport = htons(snum);
3867 ad.u.net.family = family;
3868
3869 if (family == PF_INET)
3870 ad.u.net.v4info.saddr = addr4->sin_addr.s_addr;
3871 else
3872 ad.u.net.v6info.saddr = addr6->sin6_addr;
3873
3874 err = avc_has_perm(sksec->sid, sid,
3875 sksec->sclass, node_perm, &ad);
3876 if (err)
3877 goto out;
3878 }
3879 out:
3880 return err;
3881 }
3882
3883 static int selinux_socket_connect(struct socket *sock, struct sockaddr *address, int addrlen)
3884 {
3885 struct sock *sk = sock->sk;
3886 struct sk_security_struct *sksec = sk->sk_security;
3887 int err;
3888
3889 err = sock_has_perm(current, sk, SOCKET__CONNECT);
3890 if (err)
3891 return err;
3892
3893 /*
3894 * If a TCP or DCCP socket, check name_connect permission for the port.
3895 */
3896 if (sksec->sclass == SECCLASS_TCP_SOCKET ||
3897 sksec->sclass == SECCLASS_DCCP_SOCKET) {
3898 struct common_audit_data ad;
3899 struct sockaddr_in *addr4 = NULL;
3900 struct sockaddr_in6 *addr6 = NULL;
3901 unsigned short snum;
3902 u32 sid, perm;
3903
3904 if (sk->sk_family == PF_INET) {
3905 addr4 = (struct sockaddr_in *)address;
3906 if (addrlen < sizeof(struct sockaddr_in))
3907 return -EINVAL;
3908 snum = ntohs(addr4->sin_port);
3909 } else {
3910 addr6 = (struct sockaddr_in6 *)address;
3911 if (addrlen < SIN6_LEN_RFC2133)
3912 return -EINVAL;
3913 snum = ntohs(addr6->sin6_port);
3914 }
3915
3916 err = sel_netport_sid(sk->sk_protocol, snum, &sid);
3917 if (err)
3918 goto out;
3919
3920 perm = (sksec->sclass == SECCLASS_TCP_SOCKET) ?
3921 TCP_SOCKET__NAME_CONNECT : DCCP_SOCKET__NAME_CONNECT;
3922
3923 COMMON_AUDIT_DATA_INIT(&ad, NET);
3924 ad.u.net.dport = htons(snum);
3925 ad.u.net.family = sk->sk_family;
3926 err = avc_has_perm(sksec->sid, sid, sksec->sclass, perm, &ad);
3927 if (err)
3928 goto out;
3929 }
3930
3931 err = selinux_netlbl_socket_connect(sk, address);
3932
3933 out:
3934 return err;
3935 }
3936
3937 static int selinux_socket_listen(struct socket *sock, int backlog)
3938 {
3939 return sock_has_perm(current, sock->sk, SOCKET__LISTEN);
3940 }
3941
3942 static int selinux_socket_accept(struct socket *sock, struct socket *newsock)
3943 {
3944 int err;
3945 struct inode_security_struct *isec;
3946 struct inode_security_struct *newisec;
3947
3948 err = sock_has_perm(current, sock->sk, SOCKET__ACCEPT);
3949 if (err)
3950 return err;
3951
3952 newisec = SOCK_INODE(newsock)->i_security;
3953
3954 isec = SOCK_INODE(sock)->i_security;
3955 newisec->sclass = isec->sclass;
3956 newisec->sid = isec->sid;
3957 newisec->initialized = 1;
3958
3959 return 0;
3960 }
3961
3962 static int selinux_socket_sendmsg(struct socket *sock, struct msghdr *msg,
3963 int size)
3964 {
3965 return sock_has_perm(current, sock->sk, SOCKET__WRITE);
3966 }
3967
3968 static int selinux_socket_recvmsg(struct socket *sock, struct msghdr *msg,
3969 int size, int flags)
3970 {
3971 return sock_has_perm(current, sock->sk, SOCKET__READ);
3972 }
3973
3974 static int selinux_socket_getsockname(struct socket *sock)
3975 {
3976 return sock_has_perm(current, sock->sk, SOCKET__GETATTR);
3977 }
3978
3979 static int selinux_socket_getpeername(struct socket *sock)
3980 {
3981 return sock_has_perm(current, sock->sk, SOCKET__GETATTR);
3982 }
3983
3984 static int selinux_socket_setsockopt(struct socket *sock, int level, int optname)
3985 {
3986 int err;
3987
3988 err = sock_has_perm(current, sock->sk, SOCKET__SETOPT);
3989 if (err)
3990 return err;
3991
3992 return selinux_netlbl_socket_setsockopt(sock, level, optname);
3993 }
3994
3995 static int selinux_socket_getsockopt(struct socket *sock, int level,
3996 int optname)
3997 {
3998 return sock_has_perm(current, sock->sk, SOCKET__GETOPT);
3999 }
4000
4001 static int selinux_socket_shutdown(struct socket *sock, int how)
4002 {
4003 return sock_has_perm(current, sock->sk, SOCKET__SHUTDOWN);
4004 }
4005
4006 static int selinux_socket_unix_stream_connect(struct sock *sock,
4007 struct sock *other,
4008 struct sock *newsk)
4009 {
4010 struct sk_security_struct *sksec_sock = sock->sk_security;
4011 struct sk_security_struct *sksec_other = other->sk_security;
4012 struct sk_security_struct *sksec_new = newsk->sk_security;
4013 struct common_audit_data ad;
4014 int err;
4015
4016 COMMON_AUDIT_DATA_INIT(&ad, NET);
4017 ad.u.net.sk = other;
4018
4019 err = avc_has_perm(sksec_sock->sid, sksec_other->sid,
4020 sksec_other->sclass,
4021 UNIX_STREAM_SOCKET__CONNECTTO, &ad);
4022 if (err)
4023 return err;
4024
4025 /* server child socket */
4026 sksec_new->peer_sid = sksec_sock->sid;
4027 err = security_sid_mls_copy(sksec_other->sid, sksec_sock->sid,
4028 &sksec_new->sid);
4029 if (err)
4030 return err;
4031
4032 /* connecting socket */
4033 sksec_sock->peer_sid = sksec_new->sid;
4034
4035 return 0;
4036 }
4037
4038 static int selinux_socket_unix_may_send(struct socket *sock,
4039 struct socket *other)
4040 {
4041 struct sk_security_struct *ssec = sock->sk->sk_security;
4042 struct sk_security_struct *osec = other->sk->sk_security;
4043 struct common_audit_data ad;
4044
4045 COMMON_AUDIT_DATA_INIT(&ad, NET);
4046 ad.u.net.sk = other->sk;
4047
4048 return avc_has_perm(ssec->sid, osec->sid, osec->sclass, SOCKET__SENDTO,
4049 &ad);
4050 }
4051
4052 static int selinux_inet_sys_rcv_skb(int ifindex, char *addrp, u16 family,
4053 u32 peer_sid,
4054 struct common_audit_data *ad)
4055 {
4056 int err;
4057 u32 if_sid;
4058 u32 node_sid;
4059
4060 err = sel_netif_sid(ifindex, &if_sid);
4061 if (err)
4062 return err;
4063 err = avc_has_perm(peer_sid, if_sid,
4064 SECCLASS_NETIF, NETIF__INGRESS, ad);
4065 if (err)
4066 return err;
4067
4068 err = sel_netnode_sid(addrp, family, &node_sid);
4069 if (err)
4070 return err;
4071 return avc_has_perm(peer_sid, node_sid,
4072 SECCLASS_NODE, NODE__RECVFROM, ad);
4073 }
4074
4075 static int selinux_sock_rcv_skb_compat(struct sock *sk, struct sk_buff *skb,
4076 u16 family)
4077 {
4078 int err = 0;
4079 struct sk_security_struct *sksec = sk->sk_security;
4080 u32 sk_sid = sksec->sid;
4081 struct common_audit_data ad;
4082 char *addrp;
4083
4084 COMMON_AUDIT_DATA_INIT(&ad, NET);
4085 ad.u.net.netif = skb->skb_iif;
4086 ad.u.net.family = family;
4087 err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL);
4088 if (err)
4089 return err;
4090
4091 if (selinux_secmark_enabled()) {
4092 err = avc_has_perm(sk_sid, skb->secmark, SECCLASS_PACKET,
4093 PACKET__RECV, &ad);
4094 if (err)
4095 return err;
4096 }
4097
4098 err = selinux_netlbl_sock_rcv_skb(sksec, skb, family, &ad);
4099 if (err)
4100 return err;
4101 err = selinux_xfrm_sock_rcv_skb(sksec->sid, skb, &ad);
4102
4103 return err;
4104 }
4105
4106 static int selinux_socket_sock_rcv_skb(struct sock *sk, struct sk_buff *skb)
4107 {
4108 int err;
4109 struct sk_security_struct *sksec = sk->sk_security;
4110 u16 family = sk->sk_family;
4111 u32 sk_sid = sksec->sid;
4112 struct common_audit_data ad;
4113 char *addrp;
4114 u8 secmark_active;
4115 u8 peerlbl_active;
4116
4117 if (family != PF_INET && family != PF_INET6)
4118 return 0;
4119
4120 /* Handle mapped IPv4 packets arriving via IPv6 sockets */
4121 if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
4122 family = PF_INET;
4123
4124 /* If any sort of compatibility mode is enabled then handoff processing
4125 * to the selinux_sock_rcv_skb_compat() function to deal with the
4126 * special handling. We do this in an attempt to keep this function
4127 * as fast and as clean as possible. */
4128 if (!selinux_policycap_netpeer)
4129 return selinux_sock_rcv_skb_compat(sk, skb, family);
4130
4131 secmark_active = selinux_secmark_enabled();
4132 peerlbl_active = netlbl_enabled() || selinux_xfrm_enabled();
4133 if (!secmark_active && !peerlbl_active)
4134 return 0;
4135
4136 COMMON_AUDIT_DATA_INIT(&ad, NET);
4137 ad.u.net.netif = skb->skb_iif;
4138 ad.u.net.family = family;
4139 err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL);
4140 if (err)
4141 return err;
4142
4143 if (peerlbl_active) {
4144 u32 peer_sid;
4145
4146 err = selinux_skb_peerlbl_sid(skb, family, &peer_sid);
4147 if (err)
4148 return err;
4149 err = selinux_inet_sys_rcv_skb(skb->skb_iif, addrp, family,
4150 peer_sid, &ad);
4151 if (err) {
4152 selinux_netlbl_err(skb, err, 0);
4153 return err;
4154 }
4155 err = avc_has_perm(sk_sid, peer_sid, SECCLASS_PEER,
4156 PEER__RECV, &ad);
4157 if (err)
4158 selinux_netlbl_err(skb, err, 0);
4159 }
4160
4161 if (secmark_active) {
4162 err = avc_has_perm(sk_sid, skb->secmark, SECCLASS_PACKET,
4163 PACKET__RECV, &ad);
4164 if (err)
4165 return err;
4166 }
4167
4168 return err;
4169 }
4170
4171 static int selinux_socket_getpeersec_stream(struct socket *sock, char __user *optval,
4172 int __user *optlen, unsigned len)
4173 {
4174 int err = 0;
4175 char *scontext;
4176 u32 scontext_len;
4177 struct sk_security_struct *sksec = sock->sk->sk_security;
4178 u32 peer_sid = SECSID_NULL;
4179
4180 if (sksec->sclass == SECCLASS_UNIX_STREAM_SOCKET ||
4181 sksec->sclass == SECCLASS_TCP_SOCKET)
4182 peer_sid = sksec->peer_sid;
4183 if (peer_sid == SECSID_NULL)
4184 return -ENOPROTOOPT;
4185
4186 err = security_sid_to_context(peer_sid, &scontext, &scontext_len);
4187 if (err)
4188 return err;
4189
4190 if (scontext_len > len) {
4191 err = -ERANGE;
4192 goto out_len;
4193 }
4194
4195 if (copy_to_user(optval, scontext, scontext_len))
4196 err = -EFAULT;
4197
4198 out_len:
4199 if (put_user(scontext_len, optlen))
4200 err = -EFAULT;
4201 kfree(scontext);
4202 return err;
4203 }
4204
4205 static int selinux_socket_getpeersec_dgram(struct socket *sock, struct sk_buff *skb, u32 *secid)
4206 {
4207 u32 peer_secid = SECSID_NULL;
4208 u16 family;
4209
4210 if (skb && skb->protocol == htons(ETH_P_IP))
4211 family = PF_INET;
4212 else if (skb && skb->protocol == htons(ETH_P_IPV6))
4213 family = PF_INET6;
4214 else if (sock)
4215 family = sock->sk->sk_family;
4216 else
4217 goto out;
4218
4219 if (sock && family == PF_UNIX)
4220 selinux_inode_getsecid(SOCK_INODE(sock), &peer_secid);
4221 else if (skb)
4222 selinux_skb_peerlbl_sid(skb, family, &peer_secid);
4223
4224 out:
4225 *secid = peer_secid;
4226 if (peer_secid == SECSID_NULL)
4227 return -EINVAL;
4228 return 0;
4229 }
4230
4231 static int selinux_sk_alloc_security(struct sock *sk, int family, gfp_t priority)
4232 {
4233 struct sk_security_struct *sksec;
4234
4235 sksec = kzalloc(sizeof(*sksec), priority);
4236 if (!sksec)
4237 return -ENOMEM;
4238
4239 sksec->peer_sid = SECINITSID_UNLABELED;
4240 sksec->sid = SECINITSID_UNLABELED;
4241 selinux_netlbl_sk_security_reset(sksec);
4242 sk->sk_security = sksec;
4243
4244 return 0;
4245 }
4246
4247 static void selinux_sk_free_security(struct sock *sk)
4248 {
4249 struct sk_security_struct *sksec = sk->sk_security;
4250
4251 sk->sk_security = NULL;
4252 selinux_netlbl_sk_security_free(sksec);
4253 kfree(sksec);
4254 }
4255
4256 static void selinux_sk_clone_security(const struct sock *sk, struct sock *newsk)
4257 {
4258 struct sk_security_struct *sksec = sk->sk_security;
4259 struct sk_security_struct *newsksec = newsk->sk_security;
4260
4261 newsksec->sid = sksec->sid;
4262 newsksec->peer_sid = sksec->peer_sid;
4263 newsksec->sclass = sksec->sclass;
4264
4265 selinux_netlbl_sk_security_reset(newsksec);
4266 }
4267
4268 static void selinux_sk_getsecid(struct sock *sk, u32 *secid)
4269 {
4270 if (!sk)
4271 *secid = SECINITSID_ANY_SOCKET;
4272 else {
4273 struct sk_security_struct *sksec = sk->sk_security;
4274
4275 *secid = sksec->sid;
4276 }
4277 }
4278
4279 static void selinux_sock_graft(struct sock *sk, struct socket *parent)
4280 {
4281 struct inode_security_struct *isec = SOCK_INODE(parent)->i_security;
4282 struct sk_security_struct *sksec = sk->sk_security;
4283
4284 if (sk->sk_family == PF_INET || sk->sk_family == PF_INET6 ||
4285 sk->sk_family == PF_UNIX)
4286 isec->sid = sksec->sid;
4287 sksec->sclass = isec->sclass;
4288 }
4289
4290 static int selinux_inet_conn_request(struct sock *sk, struct sk_buff *skb,
4291 struct request_sock *req)
4292 {
4293 struct sk_security_struct *sksec = sk->sk_security;
4294 int err;
4295 u16 family = sk->sk_family;
4296 u32 newsid;
4297 u32 peersid;
4298
4299 /* handle mapped IPv4 packets arriving via IPv6 sockets */
4300 if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
4301 family = PF_INET;
4302
4303 err = selinux_skb_peerlbl_sid(skb, family, &peersid);
4304 if (err)
4305 return err;
4306 if (peersid == SECSID_NULL) {
4307 req->secid = sksec->sid;
4308 req->peer_secid = SECSID_NULL;
4309 } else {
4310 err = security_sid_mls_copy(sksec->sid, peersid, &newsid);
4311 if (err)
4312 return err;
4313 req->secid = newsid;
4314 req->peer_secid = peersid;
4315 }
4316
4317 return selinux_netlbl_inet_conn_request(req, family);
4318 }
4319
4320 static void selinux_inet_csk_clone(struct sock *newsk,
4321 const struct request_sock *req)
4322 {
4323 struct sk_security_struct *newsksec = newsk->sk_security;
4324
4325 newsksec->sid = req->secid;
4326 newsksec->peer_sid = req->peer_secid;
4327 /* NOTE: Ideally, we should also get the isec->sid for the
4328 new socket in sync, but we don't have the isec available yet.
4329 So we will wait until sock_graft to do it, by which
4330 time it will have been created and available. */
4331
4332 /* We don't need to take any sort of lock here as we are the only
4333 * thread with access to newsksec */
4334 selinux_netlbl_inet_csk_clone(newsk, req->rsk_ops->family);
4335 }
4336
4337 static void selinux_inet_conn_established(struct sock *sk, struct sk_buff *skb)
4338 {
4339 u16 family = sk->sk_family;
4340 struct sk_security_struct *sksec = sk->sk_security;
4341
4342 /* handle mapped IPv4 packets arriving via IPv6 sockets */
4343 if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
4344 family = PF_INET;
4345
4346 selinux_skb_peerlbl_sid(skb, family, &sksec->peer_sid);
4347 }
4348
4349 static int selinux_secmark_relabel_packet(u32 sid)
4350 {
4351 const struct task_security_struct *__tsec;
4352 u32 tsid;
4353
4354 __tsec = current_security();
4355 tsid = __tsec->sid;
4356
4357 return avc_has_perm(tsid, sid, SECCLASS_PACKET, PACKET__RELABELTO, NULL);
4358 }
4359
4360 static void selinux_secmark_refcount_inc(void)
4361 {
4362 atomic_inc(&selinux_secmark_refcount);
4363 }
4364
4365 static void selinux_secmark_refcount_dec(void)
4366 {
4367 atomic_dec(&selinux_secmark_refcount);
4368 }
4369
4370 static void selinux_req_classify_flow(const struct request_sock *req,
4371 struct flowi *fl)
4372 {
4373 fl->flowi_secid = req->secid;
4374 }
4375
4376 static int selinux_tun_dev_create(void)
4377 {
4378 u32 sid = current_sid();
4379
4380 /* we aren't taking into account the "sockcreate" SID since the socket
4381 * that is being created here is not a socket in the traditional sense,
4382 * instead it is a private sock, accessible only to the kernel, and
4383 * representing a wide range of network traffic spanning multiple
4384 * connections unlike traditional sockets - check the TUN driver to
4385 * get a better understanding of why this socket is special */
4386
4387 return avc_has_perm(sid, sid, SECCLASS_TUN_SOCKET, TUN_SOCKET__CREATE,
4388 NULL);
4389 }
4390
4391 static void selinux_tun_dev_post_create(struct sock *sk)
4392 {
4393 struct sk_security_struct *sksec = sk->sk_security;
4394
4395 /* we don't currently perform any NetLabel based labeling here and it
4396 * isn't clear that we would want to do so anyway; while we could apply
4397 * labeling without the support of the TUN user the resulting labeled
4398 * traffic from the other end of the connection would almost certainly
4399 * cause confusion to the TUN user that had no idea network labeling
4400 * protocols were being used */
4401
4402 /* see the comments in selinux_tun_dev_create() about why we don't use
4403 * the sockcreate SID here */
4404
4405 sksec->sid = current_sid();
4406 sksec->sclass = SECCLASS_TUN_SOCKET;
4407 }
4408
4409 static int selinux_tun_dev_attach(struct sock *sk)
4410 {
4411 struct sk_security_struct *sksec = sk->sk_security;
4412 u32 sid = current_sid();
4413 int err;
4414
4415 err = avc_has_perm(sid, sksec->sid, SECCLASS_TUN_SOCKET,
4416 TUN_SOCKET__RELABELFROM, NULL);
4417 if (err)
4418 return err;
4419 err = avc_has_perm(sid, sid, SECCLASS_TUN_SOCKET,
4420 TUN_SOCKET__RELABELTO, NULL);
4421 if (err)
4422 return err;
4423
4424 sksec->sid = sid;
4425
4426 return 0;
4427 }
4428
4429 static int selinux_nlmsg_perm(struct sock *sk, struct sk_buff *skb)
4430 {
4431 int err = 0;
4432 u32 perm;
4433 struct nlmsghdr *nlh;
4434 struct sk_security_struct *sksec = sk->sk_security;
4435
4436 if (skb->len < NLMSG_SPACE(0)) {
4437 err = -EINVAL;
4438 goto out;
4439 }
4440 nlh = nlmsg_hdr(skb);
4441
4442 err = selinux_nlmsg_lookup(sksec->sclass, nlh->nlmsg_type, &perm);
4443 if (err) {
4444 if (err == -EINVAL) {
4445 audit_log(current->audit_context, GFP_KERNEL, AUDIT_SELINUX_ERR,
4446 "SELinux: unrecognized netlink message"
4447 " type=%hu for sclass=%hu\n",
4448 nlh->nlmsg_type, sksec->sclass);
4449 if (!selinux_enforcing || security_get_allow_unknown())
4450 err = 0;
4451 }
4452
4453 /* Ignore */
4454 if (err == -ENOENT)
4455 err = 0;
4456 goto out;
4457 }
4458
4459 err = sock_has_perm(current, sk, perm);
4460 out:
4461 return err;
4462 }
4463
4464 #ifdef CONFIG_NETFILTER
4465
4466 static unsigned int selinux_ip_forward(struct sk_buff *skb, int ifindex,
4467 u16 family)
4468 {
4469 int err;
4470 char *addrp;
4471 u32 peer_sid;
4472 struct common_audit_data ad;
4473 u8 secmark_active;
4474 u8 netlbl_active;
4475 u8 peerlbl_active;
4476
4477 if (!selinux_policycap_netpeer)
4478 return NF_ACCEPT;
4479
4480 secmark_active = selinux_secmark_enabled();
4481 netlbl_active = netlbl_enabled();
4482 peerlbl_active = netlbl_active || selinux_xfrm_enabled();
4483 if (!secmark_active && !peerlbl_active)
4484 return NF_ACCEPT;
4485
4486 if (selinux_skb_peerlbl_sid(skb, family, &peer_sid) != 0)
4487 return NF_DROP;
4488
4489 COMMON_AUDIT_DATA_INIT(&ad, NET);
4490 ad.u.net.netif = ifindex;
4491 ad.u.net.family = family;
4492 if (selinux_parse_skb(skb, &ad, &addrp, 1, NULL) != 0)
4493 return NF_DROP;
4494
4495 if (peerlbl_active) {
4496 err = selinux_inet_sys_rcv_skb(ifindex, addrp, family,
4497 peer_sid, &ad);
4498 if (err) {
4499 selinux_netlbl_err(skb, err, 1);
4500 return NF_DROP;
4501 }
4502 }
4503
4504 if (secmark_active)
4505 if (avc_has_perm(peer_sid, skb->secmark,
4506 SECCLASS_PACKET, PACKET__FORWARD_IN, &ad))
4507 return NF_DROP;
4508
4509 if (netlbl_active)
4510 /* we do this in the FORWARD path and not the POST_ROUTING
4511 * path because we want to make sure we apply the necessary
4512 * labeling before IPsec is applied so we can leverage AH
4513 * protection */
4514 if (selinux_netlbl_skbuff_setsid(skb, family, peer_sid) != 0)
4515 return NF_DROP;
4516
4517 return NF_ACCEPT;
4518 }
4519
4520 static unsigned int selinux_ipv4_forward(unsigned int hooknum,
4521 struct sk_buff *skb,
4522 const struct net_device *in,
4523 const struct net_device *out,
4524 int (*okfn)(struct sk_buff *))
4525 {
4526 return selinux_ip_forward(skb, in->ifindex, PF_INET);
4527 }
4528
4529 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
4530 static unsigned int selinux_ipv6_forward(unsigned int hooknum,
4531 struct sk_buff *skb,
4532 const struct net_device *in,
4533 const struct net_device *out,
4534 int (*okfn)(struct sk_buff *))
4535 {
4536 return selinux_ip_forward(skb, in->ifindex, PF_INET6);
4537 }
4538 #endif /* IPV6 */
4539
4540 static unsigned int selinux_ip_output(struct sk_buff *skb,
4541 u16 family)
4542 {
4543 u32 sid;
4544
4545 if (!netlbl_enabled())
4546 return NF_ACCEPT;
4547
4548 /* we do this in the LOCAL_OUT path and not the POST_ROUTING path
4549 * because we want to make sure we apply the necessary labeling
4550 * before IPsec is applied so we can leverage AH protection */
4551 if (skb->sk) {
4552 struct sk_security_struct *sksec = skb->sk->sk_security;
4553 sid = sksec->sid;
4554 } else
4555 sid = SECINITSID_KERNEL;
4556 if (selinux_netlbl_skbuff_setsid(skb, family, sid) != 0)
4557 return NF_DROP;
4558
4559 return NF_ACCEPT;
4560 }
4561
4562 static unsigned int selinux_ipv4_output(unsigned int hooknum,
4563 struct sk_buff *skb,
4564 const struct net_device *in,
4565 const struct net_device *out,
4566 int (*okfn)(struct sk_buff *))
4567 {
4568 return selinux_ip_output(skb, PF_INET);
4569 }
4570
4571 static unsigned int selinux_ip_postroute_compat(struct sk_buff *skb,
4572 int ifindex,
4573 u16 family)
4574 {
4575 struct sock *sk = skb->sk;
4576 struct sk_security_struct *sksec;
4577 struct common_audit_data ad;
4578 char *addrp;
4579 u8 proto;
4580
4581 if (sk == NULL)
4582 return NF_ACCEPT;
4583 sksec = sk->sk_security;
4584
4585 COMMON_AUDIT_DATA_INIT(&ad, NET);
4586 ad.u.net.netif = ifindex;
4587 ad.u.net.family = family;
4588 if (selinux_parse_skb(skb, &ad, &addrp, 0, &proto))
4589 return NF_DROP;
4590
4591 if (selinux_secmark_enabled())
4592 if (avc_has_perm(sksec->sid, skb->secmark,
4593 SECCLASS_PACKET, PACKET__SEND, &ad))
4594 return NF_DROP_ERR(-ECONNREFUSED);
4595
4596 if (selinux_xfrm_postroute_last(sksec->sid, skb, &ad, proto))
4597 return NF_DROP_ERR(-ECONNREFUSED);
4598
4599 return NF_ACCEPT;
4600 }
4601
4602 static unsigned int selinux_ip_postroute(struct sk_buff *skb, int ifindex,
4603 u16 family)
4604 {
4605 u32 secmark_perm;
4606 u32 peer_sid;
4607 struct sock *sk;
4608 struct common_audit_data ad;
4609 char *addrp;
4610 u8 secmark_active;
4611 u8 peerlbl_active;
4612
4613 /* If any sort of compatibility mode is enabled then handoff processing
4614 * to the selinux_ip_postroute_compat() function to deal with the
4615 * special handling. We do this in an attempt to keep this function
4616 * as fast and as clean as possible. */
4617 if (!selinux_policycap_netpeer)
4618 return selinux_ip_postroute_compat(skb, ifindex, family);
4619 #ifdef CONFIG_XFRM
4620 /* If skb->dst->xfrm is non-NULL then the packet is undergoing an IPsec
4621 * packet transformation so allow the packet to pass without any checks
4622 * since we'll have another chance to perform access control checks
4623 * when the packet is on it's final way out.
4624 * NOTE: there appear to be some IPv6 multicast cases where skb->dst
4625 * is NULL, in this case go ahead and apply access control. */
4626 if (skb_dst(skb) != NULL && skb_dst(skb)->xfrm != NULL)
4627 return NF_ACCEPT;
4628 #endif
4629 secmark_active = selinux_secmark_enabled();
4630 peerlbl_active = netlbl_enabled() || selinux_xfrm_enabled();
4631 if (!secmark_active && !peerlbl_active)
4632 return NF_ACCEPT;
4633
4634 /* if the packet is being forwarded then get the peer label from the
4635 * packet itself; otherwise check to see if it is from a local
4636 * application or the kernel, if from an application get the peer label
4637 * from the sending socket, otherwise use the kernel's sid */
4638 sk = skb->sk;
4639 if (sk == NULL) {
4640 if (skb->skb_iif) {
4641 secmark_perm = PACKET__FORWARD_OUT;
4642 if (selinux_skb_peerlbl_sid(skb, family, &peer_sid))
4643 return NF_DROP;
4644 } else {
4645 secmark_perm = PACKET__SEND;
4646 peer_sid = SECINITSID_KERNEL;
4647 }
4648 } else {
4649 struct sk_security_struct *sksec = sk->sk_security;
4650 peer_sid = sksec->sid;
4651 secmark_perm = PACKET__SEND;
4652 }
4653
4654 COMMON_AUDIT_DATA_INIT(&ad, NET);
4655 ad.u.net.netif = ifindex;
4656 ad.u.net.family = family;
4657 if (selinux_parse_skb(skb, &ad, &addrp, 0, NULL))
4658 return NF_DROP;
4659
4660 if (secmark_active)
4661 if (avc_has_perm(peer_sid, skb->secmark,
4662 SECCLASS_PACKET, secmark_perm, &ad))
4663 return NF_DROP_ERR(-ECONNREFUSED);
4664
4665 if (peerlbl_active) {
4666 u32 if_sid;
4667 u32 node_sid;
4668
4669 if (sel_netif_sid(ifindex, &if_sid))
4670 return NF_DROP;
4671 if (avc_has_perm(peer_sid, if_sid,
4672 SECCLASS_NETIF, NETIF__EGRESS, &ad))
4673 return NF_DROP_ERR(-ECONNREFUSED);
4674
4675 if (sel_netnode_sid(addrp, family, &node_sid))
4676 return NF_DROP;
4677 if (avc_has_perm(peer_sid, node_sid,
4678 SECCLASS_NODE, NODE__SENDTO, &ad))
4679 return NF_DROP_ERR(-ECONNREFUSED);
4680 }
4681
4682 return NF_ACCEPT;
4683 }
4684
4685 static unsigned int selinux_ipv4_postroute(unsigned int hooknum,
4686 struct sk_buff *skb,
4687 const struct net_device *in,
4688 const struct net_device *out,
4689 int (*okfn)(struct sk_buff *))
4690 {
4691 return selinux_ip_postroute(skb, out->ifindex, PF_INET);
4692 }
4693
4694 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
4695 static unsigned int selinux_ipv6_postroute(unsigned int hooknum,
4696 struct sk_buff *skb,
4697 const struct net_device *in,
4698 const struct net_device *out,
4699 int (*okfn)(struct sk_buff *))
4700 {
4701 return selinux_ip_postroute(skb, out->ifindex, PF_INET6);
4702 }
4703 #endif /* IPV6 */
4704
4705 #endif /* CONFIG_NETFILTER */
4706
4707 static int selinux_netlink_send(struct sock *sk, struct sk_buff *skb)
4708 {
4709 int err;
4710
4711 err = cap_netlink_send(sk, skb);
4712 if (err)
4713 return err;
4714
4715 return selinux_nlmsg_perm(sk, skb);
4716 }
4717
4718 static int ipc_alloc_security(struct task_struct *task,
4719 struct kern_ipc_perm *perm,
4720 u16 sclass)
4721 {
4722 struct ipc_security_struct *isec;
4723 u32 sid;
4724
4725 isec = kzalloc(sizeof(struct ipc_security_struct), GFP_KERNEL);
4726 if (!isec)
4727 return -ENOMEM;
4728
4729 sid = task_sid(task);
4730 isec->sclass = sclass;
4731 isec->sid = sid;
4732 perm->security = isec;
4733
4734 return 0;
4735 }
4736
4737 static void ipc_free_security(struct kern_ipc_perm *perm)
4738 {
4739 struct ipc_security_struct *isec = perm->security;
4740 perm->security = NULL;
4741 kfree(isec);
4742 }
4743
4744 static int msg_msg_alloc_security(struct msg_msg *msg)
4745 {
4746 struct msg_security_struct *msec;
4747
4748 msec = kzalloc(sizeof(struct msg_security_struct), GFP_KERNEL);
4749 if (!msec)
4750 return -ENOMEM;
4751
4752 msec->sid = SECINITSID_UNLABELED;
4753 msg->security = msec;
4754
4755 return 0;
4756 }
4757
4758 static void msg_msg_free_security(struct msg_msg *msg)
4759 {
4760 struct msg_security_struct *msec = msg->security;
4761
4762 msg->security = NULL;
4763 kfree(msec);
4764 }
4765
4766 static int ipc_has_perm(struct kern_ipc_perm *ipc_perms,
4767 u32 perms)
4768 {
4769 struct ipc_security_struct *isec;
4770 struct common_audit_data ad;
4771 u32 sid = current_sid();
4772
4773 isec = ipc_perms->security;
4774
4775 COMMON_AUDIT_DATA_INIT(&ad, IPC);
4776 ad.u.ipc_id = ipc_perms->key;
4777
4778 return avc_has_perm(sid, isec->sid, isec->sclass, perms, &ad);
4779 }
4780
4781 static int selinux_msg_msg_alloc_security(struct msg_msg *msg)
4782 {
4783 return msg_msg_alloc_security(msg);
4784 }
4785
4786 static void selinux_msg_msg_free_security(struct msg_msg *msg)
4787 {
4788 msg_msg_free_security(msg);
4789 }
4790
4791 /* message queue security operations */
4792 static int selinux_msg_queue_alloc_security(struct msg_queue *msq)
4793 {
4794 struct ipc_security_struct *isec;
4795 struct common_audit_data ad;
4796 u32 sid = current_sid();
4797 int rc;
4798
4799 rc = ipc_alloc_security(current, &msq->q_perm, SECCLASS_MSGQ);
4800 if (rc)
4801 return rc;
4802
4803 isec = msq->q_perm.security;
4804
4805 COMMON_AUDIT_DATA_INIT(&ad, IPC);
4806 ad.u.ipc_id = msq->q_perm.key;
4807
4808 rc = avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
4809 MSGQ__CREATE, &ad);
4810 if (rc) {
4811 ipc_free_security(&msq->q_perm);
4812 return rc;
4813 }
4814 return 0;
4815 }
4816
4817 static void selinux_msg_queue_free_security(struct msg_queue *msq)
4818 {
4819 ipc_free_security(&msq->q_perm);
4820 }
4821
4822 static int selinux_msg_queue_associate(struct msg_queue *msq, int msqflg)
4823 {
4824 struct ipc_security_struct *isec;
4825 struct common_audit_data ad;
4826 u32 sid = current_sid();
4827
4828 isec = msq->q_perm.security;
4829
4830 COMMON_AUDIT_DATA_INIT(&ad, IPC);
4831 ad.u.ipc_id = msq->q_perm.key;
4832
4833 return avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
4834 MSGQ__ASSOCIATE, &ad);
4835 }
4836
4837 static int selinux_msg_queue_msgctl(struct msg_queue *msq, int cmd)
4838 {
4839 int err;
4840 int perms;
4841
4842 switch (cmd) {
4843 case IPC_INFO:
4844 case MSG_INFO:
4845 /* No specific object, just general system-wide information. */
4846 return task_has_system(current, SYSTEM__IPC_INFO);
4847 case IPC_STAT:
4848 case MSG_STAT:
4849 perms = MSGQ__GETATTR | MSGQ__ASSOCIATE;
4850 break;
4851 case IPC_SET:
4852 perms = MSGQ__SETATTR;
4853 break;
4854 case IPC_RMID:
4855 perms = MSGQ__DESTROY;
4856 break;
4857 default:
4858 return 0;
4859 }
4860
4861 err = ipc_has_perm(&msq->q_perm, perms);
4862 return err;
4863 }
4864
4865 static int selinux_msg_queue_msgsnd(struct msg_queue *msq, struct msg_msg *msg, int msqflg)
4866 {
4867 struct ipc_security_struct *isec;
4868 struct msg_security_struct *msec;
4869 struct common_audit_data ad;
4870 u32 sid = current_sid();
4871 int rc;
4872
4873 isec = msq->q_perm.security;
4874 msec = msg->security;
4875
4876 /*
4877 * First time through, need to assign label to the message
4878 */
4879 if (msec->sid == SECINITSID_UNLABELED) {
4880 /*
4881 * Compute new sid based on current process and
4882 * message queue this message will be stored in
4883 */
4884 rc = security_transition_sid(sid, isec->sid, SECCLASS_MSG,
4885 NULL, &msec->sid);
4886 if (rc)
4887 return rc;
4888 }
4889
4890 COMMON_AUDIT_DATA_INIT(&ad, IPC);
4891 ad.u.ipc_id = msq->q_perm.key;
4892
4893 /* Can this process write to the queue? */
4894 rc = avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
4895 MSGQ__WRITE, &ad);
4896 if (!rc)
4897 /* Can this process send the message */
4898 rc = avc_has_perm(sid, msec->sid, SECCLASS_MSG,
4899 MSG__SEND, &ad);
4900 if (!rc)
4901 /* Can the message be put in the queue? */
4902 rc = avc_has_perm(msec->sid, isec->sid, SECCLASS_MSGQ,
4903 MSGQ__ENQUEUE, &ad);
4904
4905 return rc;
4906 }
4907
4908 static int selinux_msg_queue_msgrcv(struct msg_queue *msq, struct msg_msg *msg,
4909 struct task_struct *target,
4910 long type, int mode)
4911 {
4912 struct ipc_security_struct *isec;
4913 struct msg_security_struct *msec;
4914 struct common_audit_data ad;
4915 u32 sid = task_sid(target);
4916 int rc;
4917
4918 isec = msq->q_perm.security;
4919 msec = msg->security;
4920
4921 COMMON_AUDIT_DATA_INIT(&ad, IPC);
4922 ad.u.ipc_id = msq->q_perm.key;
4923
4924 rc = avc_has_perm(sid, isec->sid,
4925 SECCLASS_MSGQ, MSGQ__READ, &ad);
4926 if (!rc)
4927 rc = avc_has_perm(sid, msec->sid,
4928 SECCLASS_MSG, MSG__RECEIVE, &ad);
4929 return rc;
4930 }
4931
4932 /* Shared Memory security operations */
4933 static int selinux_shm_alloc_security(struct shmid_kernel *shp)
4934 {
4935 struct ipc_security_struct *isec;
4936 struct common_audit_data ad;
4937 u32 sid = current_sid();
4938 int rc;
4939
4940 rc = ipc_alloc_security(current, &shp->shm_perm, SECCLASS_SHM);
4941 if (rc)
4942 return rc;
4943
4944 isec = shp->shm_perm.security;
4945
4946 COMMON_AUDIT_DATA_INIT(&ad, IPC);
4947 ad.u.ipc_id = shp->shm_perm.key;
4948
4949 rc = avc_has_perm(sid, isec->sid, SECCLASS_SHM,
4950 SHM__CREATE, &ad);
4951 if (rc) {
4952 ipc_free_security(&shp->shm_perm);
4953 return rc;
4954 }
4955 return 0;
4956 }
4957
4958 static void selinux_shm_free_security(struct shmid_kernel *shp)
4959 {
4960 ipc_free_security(&shp->shm_perm);
4961 }
4962
4963 static int selinux_shm_associate(struct shmid_kernel *shp, int shmflg)
4964 {
4965 struct ipc_security_struct *isec;
4966 struct common_audit_data ad;
4967 u32 sid = current_sid();
4968
4969 isec = shp->shm_perm.security;
4970
4971 COMMON_AUDIT_DATA_INIT(&ad, IPC);
4972 ad.u.ipc_id = shp->shm_perm.key;
4973
4974 return avc_has_perm(sid, isec->sid, SECCLASS_SHM,
4975 SHM__ASSOCIATE, &ad);
4976 }
4977
4978 /* Note, at this point, shp is locked down */
4979 static int selinux_shm_shmctl(struct shmid_kernel *shp, int cmd)
4980 {
4981 int perms;
4982 int err;
4983
4984 switch (cmd) {
4985 case IPC_INFO:
4986 case SHM_INFO:
4987 /* No specific object, just general system-wide information. */
4988 return task_has_system(current, SYSTEM__IPC_INFO);
4989 case IPC_STAT:
4990 case SHM_STAT:
4991 perms = SHM__GETATTR | SHM__ASSOCIATE;
4992 break;
4993 case IPC_SET:
4994 perms = SHM__SETATTR;
4995 break;
4996 case SHM_LOCK:
4997 case SHM_UNLOCK:
4998 perms = SHM__LOCK;
4999 break;
5000 case IPC_RMID:
5001 perms = SHM__DESTROY;
5002 break;
5003 default:
5004 return 0;
5005 }
5006
5007 err = ipc_has_perm(&shp->shm_perm, perms);
5008 return err;
5009 }
5010
5011 static int selinux_shm_shmat(struct shmid_kernel *shp,
5012 char __user *shmaddr, int shmflg)
5013 {
5014 u32 perms;
5015
5016 if (shmflg & SHM_RDONLY)
5017 perms = SHM__READ;
5018 else
5019 perms = SHM__READ | SHM__WRITE;
5020
5021 return ipc_has_perm(&shp->shm_perm, perms);
5022 }
5023
5024 /* Semaphore security operations */
5025 static int selinux_sem_alloc_security(struct sem_array *sma)
5026 {
5027 struct ipc_security_struct *isec;
5028 struct common_audit_data ad;
5029 u32 sid = current_sid();
5030 int rc;
5031
5032 rc = ipc_alloc_security(current, &sma->sem_perm, SECCLASS_SEM);
5033 if (rc)
5034 return rc;
5035
5036 isec = sma->sem_perm.security;
5037
5038 COMMON_AUDIT_DATA_INIT(&ad, IPC);
5039 ad.u.ipc_id = sma->sem_perm.key;
5040
5041 rc = avc_has_perm(sid, isec->sid, SECCLASS_SEM,
5042 SEM__CREATE, &ad);
5043 if (rc) {
5044 ipc_free_security(&sma->sem_perm);
5045 return rc;
5046 }
5047 return 0;
5048 }
5049
5050 static void selinux_sem_free_security(struct sem_array *sma)
5051 {
5052 ipc_free_security(&sma->sem_perm);
5053 }
5054
5055 static int selinux_sem_associate(struct sem_array *sma, int semflg)
5056 {
5057 struct ipc_security_struct *isec;
5058 struct common_audit_data ad;
5059 u32 sid = current_sid();
5060
5061 isec = sma->sem_perm.security;
5062
5063 COMMON_AUDIT_DATA_INIT(&ad, IPC);
5064 ad.u.ipc_id = sma->sem_perm.key;
5065
5066 return avc_has_perm(sid, isec->sid, SECCLASS_SEM,
5067 SEM__ASSOCIATE, &ad);
5068 }
5069
5070 /* Note, at this point, sma is locked down */
5071 static int selinux_sem_semctl(struct sem_array *sma, int cmd)
5072 {
5073 int err;
5074 u32 perms;
5075
5076 switch (cmd) {
5077 case IPC_INFO:
5078 case SEM_INFO:
5079 /* No specific object, just general system-wide information. */
5080 return task_has_system(current, SYSTEM__IPC_INFO);
5081 case GETPID:
5082 case GETNCNT:
5083 case GETZCNT:
5084 perms = SEM__GETATTR;
5085 break;
5086 case GETVAL:
5087 case GETALL:
5088 perms = SEM__READ;
5089 break;
5090 case SETVAL:
5091 case SETALL:
5092 perms = SEM__WRITE;
5093 break;
5094 case IPC_RMID:
5095 perms = SEM__DESTROY;
5096 break;
5097 case IPC_SET:
5098 perms = SEM__SETATTR;
5099 break;
5100 case IPC_STAT:
5101 case SEM_STAT:
5102 perms = SEM__GETATTR | SEM__ASSOCIATE;
5103 break;
5104 default:
5105 return 0;
5106 }
5107
5108 err = ipc_has_perm(&sma->sem_perm, perms);
5109 return err;
5110 }
5111
5112 static int selinux_sem_semop(struct sem_array *sma,
5113 struct sembuf *sops, unsigned nsops, int alter)
5114 {
5115 u32 perms;
5116
5117 if (alter)
5118 perms = SEM__READ | SEM__WRITE;
5119 else
5120 perms = SEM__READ;
5121
5122 return ipc_has_perm(&sma->sem_perm, perms);
5123 }
5124
5125 static int selinux_ipc_permission(struct kern_ipc_perm *ipcp, short flag)
5126 {
5127 u32 av = 0;
5128
5129 av = 0;
5130 if (flag & S_IRUGO)
5131 av |= IPC__UNIX_READ;
5132 if (flag & S_IWUGO)
5133 av |= IPC__UNIX_WRITE;
5134
5135 if (av == 0)
5136 return 0;
5137
5138 return ipc_has_perm(ipcp, av);
5139 }
5140
5141 static void selinux_ipc_getsecid(struct kern_ipc_perm *ipcp, u32 *secid)
5142 {
5143 struct ipc_security_struct *isec = ipcp->security;
5144 *secid = isec->sid;
5145 }
5146
5147 static void selinux_d_instantiate(struct dentry *dentry, struct inode *inode)
5148 {
5149 if (inode)
5150 inode_doinit_with_dentry(inode, dentry);
5151 }
5152
5153 static int selinux_getprocattr(struct task_struct *p,
5154 char *name, char **value)
5155 {
5156 const struct task_security_struct *__tsec;
5157 u32 sid;
5158 int error;
5159 unsigned len;
5160
5161 if (current != p) {
5162 error = current_has_perm(p, PROCESS__GETATTR);
5163 if (error)
5164 return error;
5165 }
5166
5167 rcu_read_lock();
5168 __tsec = __task_cred(p)->security;
5169
5170 if (!strcmp(name, "current"))
5171 sid = __tsec->sid;
5172 else if (!strcmp(name, "prev"))
5173 sid = __tsec->osid;
5174 else if (!strcmp(name, "exec"))
5175 sid = __tsec->exec_sid;
5176 else if (!strcmp(name, "fscreate"))
5177 sid = __tsec->create_sid;
5178 else if (!strcmp(name, "keycreate"))
5179 sid = __tsec->keycreate_sid;
5180 else if (!strcmp(name, "sockcreate"))
5181 sid = __tsec->sockcreate_sid;
5182 else
5183 goto invalid;
5184 rcu_read_unlock();
5185
5186 if (!sid)
5187 return 0;
5188
5189 error = security_sid_to_context(sid, value, &len);
5190 if (error)
5191 return error;
5192 return len;
5193
5194 invalid:
5195 rcu_read_unlock();
5196 return -EINVAL;
5197 }
5198
5199 static int selinux_setprocattr(struct task_struct *p,
5200 char *name, void *value, size_t size)
5201 {
5202 struct task_security_struct *tsec;
5203 struct task_struct *tracer;
5204 struct cred *new;
5205 u32 sid = 0, ptsid;
5206 int error;
5207 char *str = value;
5208
5209 if (current != p) {
5210 /* SELinux only allows a process to change its own
5211 security attributes. */
5212 return -EACCES;
5213 }
5214
5215 /*
5216 * Basic control over ability to set these attributes at all.
5217 * current == p, but we'll pass them separately in case the
5218 * above restriction is ever removed.
5219 */
5220 if (!strcmp(name, "exec"))
5221 error = current_has_perm(p, PROCESS__SETEXEC);
5222 else if (!strcmp(name, "fscreate"))
5223 error = current_has_perm(p, PROCESS__SETFSCREATE);
5224 else if (!strcmp(name, "keycreate"))
5225 error = current_has_perm(p, PROCESS__SETKEYCREATE);
5226 else if (!strcmp(name, "sockcreate"))
5227 error = current_has_perm(p, PROCESS__SETSOCKCREATE);
5228 else if (!strcmp(name, "current"))
5229 error = current_has_perm(p, PROCESS__SETCURRENT);
5230 else
5231 error = -EINVAL;
5232 if (error)
5233 return error;
5234
5235 /* Obtain a SID for the context, if one was specified. */
5236 if (size && str[1] && str[1] != '\n') {
5237 if (str[size-1] == '\n') {
5238 str[size-1] = 0;
5239 size--;
5240 }
5241 error = security_context_to_sid(value, size, &sid);
5242 if (error == -EINVAL && !strcmp(name, "fscreate")) {
5243 if (!capable(CAP_MAC_ADMIN))
5244 return error;
5245 error = security_context_to_sid_force(value, size,
5246 &sid);
5247 }
5248 if (error)
5249 return error;
5250 }
5251
5252 new = prepare_creds();
5253 if (!new)
5254 return -ENOMEM;
5255
5256 /* Permission checking based on the specified context is
5257 performed during the actual operation (execve,
5258 open/mkdir/...), when we know the full context of the
5259 operation. See selinux_bprm_set_creds for the execve
5260 checks and may_create for the file creation checks. The
5261 operation will then fail if the context is not permitted. */
5262 tsec = new->security;
5263 if (!strcmp(name, "exec")) {
5264 tsec->exec_sid = sid;
5265 } else if (!strcmp(name, "fscreate")) {
5266 tsec->create_sid = sid;
5267 } else if (!strcmp(name, "keycreate")) {
5268 error = may_create_key(sid, p);
5269 if (error)
5270 goto abort_change;
5271 tsec->keycreate_sid = sid;
5272 } else if (!strcmp(name, "sockcreate")) {
5273 tsec->sockcreate_sid = sid;
5274 } else if (!strcmp(name, "current")) {
5275 error = -EINVAL;
5276 if (sid == 0)
5277 goto abort_change;
5278
5279 /* Only allow single threaded processes to change context */
5280 error = -EPERM;
5281 if (!current_is_single_threaded()) {
5282 error = security_bounded_transition(tsec->sid, sid);
5283 if (error)
5284 goto abort_change;
5285 }
5286
5287 /* Check permissions for the transition. */
5288 error = avc_has_perm(tsec->sid, sid, SECCLASS_PROCESS,
5289 PROCESS__DYNTRANSITION, NULL);
5290 if (error)
5291 goto abort_change;
5292
5293 /* Check for ptracing, and update the task SID if ok.
5294 Otherwise, leave SID unchanged and fail. */
5295 ptsid = 0;
5296 task_lock(p);
5297 tracer = ptrace_parent(p);
5298 if (tracer)
5299 ptsid = task_sid(tracer);
5300 task_unlock(p);
5301
5302 if (tracer) {
5303 error = avc_has_perm(ptsid, sid, SECCLASS_PROCESS,
5304 PROCESS__PTRACE, NULL);
5305 if (error)
5306 goto abort_change;
5307 }
5308
5309 tsec->sid = sid;
5310 } else {
5311 error = -EINVAL;
5312 goto abort_change;
5313 }
5314
5315 commit_creds(new);
5316 return size;
5317
5318 abort_change:
5319 abort_creds(new);
5320 return error;
5321 }
5322
5323 static int selinux_secid_to_secctx(u32 secid, char **secdata, u32 *seclen)
5324 {
5325 return security_sid_to_context(secid, secdata, seclen);
5326 }
5327
5328 static int selinux_secctx_to_secid(const char *secdata, u32 seclen, u32 *secid)
5329 {
5330 return security_context_to_sid(secdata, seclen, secid);
5331 }
5332
5333 static void selinux_release_secctx(char *secdata, u32 seclen)
5334 {
5335 kfree(secdata);
5336 }
5337
5338 /*
5339 * called with inode->i_mutex locked
5340 */
5341 static int selinux_inode_notifysecctx(struct inode *inode, void *ctx, u32 ctxlen)
5342 {
5343 return selinux_inode_setsecurity(inode, XATTR_SELINUX_SUFFIX, ctx, ctxlen, 0);
5344 }
5345
5346 /*
5347 * called with inode->i_mutex locked
5348 */
5349 static int selinux_inode_setsecctx(struct dentry *dentry, void *ctx, u32 ctxlen)
5350 {
5351 return __vfs_setxattr_noperm(dentry, XATTR_NAME_SELINUX, ctx, ctxlen, 0);
5352 }
5353
5354 static int selinux_inode_getsecctx(struct inode *inode, void **ctx, u32 *ctxlen)
5355 {
5356 int len = 0;
5357 len = selinux_inode_getsecurity(inode, XATTR_SELINUX_SUFFIX,
5358 ctx, true);
5359 if (len < 0)
5360 return len;
5361 *ctxlen = len;
5362 return 0;
5363 }
5364 #ifdef CONFIG_KEYS
5365
5366 static int selinux_key_alloc(struct key *k, const struct cred *cred,
5367 unsigned long flags)
5368 {
5369 const struct task_security_struct *tsec;
5370 struct key_security_struct *ksec;
5371
5372 ksec = kzalloc(sizeof(struct key_security_struct), GFP_KERNEL);
5373 if (!ksec)
5374 return -ENOMEM;
5375
5376 tsec = cred->security;
5377 if (tsec->keycreate_sid)
5378 ksec->sid = tsec->keycreate_sid;
5379 else
5380 ksec->sid = tsec->sid;
5381
5382 k->security = ksec;
5383 return 0;
5384 }
5385
5386 static void selinux_key_free(struct key *k)
5387 {
5388 struct key_security_struct *ksec = k->security;
5389
5390 k->security = NULL;
5391 kfree(ksec);
5392 }
5393
5394 static int selinux_key_permission(key_ref_t key_ref,
5395 const struct cred *cred,
5396 key_perm_t perm)
5397 {
5398 struct key *key;
5399 struct key_security_struct *ksec;
5400 u32 sid;
5401
5402 /* if no specific permissions are requested, we skip the
5403 permission check. No serious, additional covert channels
5404 appear to be created. */
5405 if (perm == 0)
5406 return 0;
5407
5408 sid = cred_sid(cred);
5409
5410 key = key_ref_to_ptr(key_ref);
5411 ksec = key->security;
5412
5413 return avc_has_perm(sid, ksec->sid, SECCLASS_KEY, perm, NULL);
5414 }
5415
5416 static int selinux_key_getsecurity(struct key *key, char **_buffer)
5417 {
5418 struct key_security_struct *ksec = key->security;
5419 char *context = NULL;
5420 unsigned len;
5421 int rc;
5422
5423 rc = security_sid_to_context(ksec->sid, &context, &len);
5424 if (!rc)
5425 rc = len;
5426 *_buffer = context;
5427 return rc;
5428 }
5429
5430 #endif
5431
5432 static struct security_operations selinux_ops = {
5433 .name = "selinux",
5434
5435 .ptrace_access_check = selinux_ptrace_access_check,
5436 .ptrace_traceme = selinux_ptrace_traceme,
5437 .capget = selinux_capget,
5438 .capset = selinux_capset,
5439 .capable = selinux_capable,
5440 .quotactl = selinux_quotactl,
5441 .quota_on = selinux_quota_on,
5442 .syslog = selinux_syslog,
5443 .vm_enough_memory = selinux_vm_enough_memory,
5444
5445 .netlink_send = selinux_netlink_send,
5446
5447 .bprm_set_creds = selinux_bprm_set_creds,
5448 .bprm_committing_creds = selinux_bprm_committing_creds,
5449 .bprm_committed_creds = selinux_bprm_committed_creds,
5450 .bprm_secureexec = selinux_bprm_secureexec,
5451
5452 .sb_alloc_security = selinux_sb_alloc_security,
5453 .sb_free_security = selinux_sb_free_security,
5454 .sb_copy_data = selinux_sb_copy_data,
5455 .sb_remount = selinux_sb_remount,
5456 .sb_kern_mount = selinux_sb_kern_mount,
5457 .sb_show_options = selinux_sb_show_options,
5458 .sb_statfs = selinux_sb_statfs,
5459 .sb_mount = selinux_mount,
5460 .sb_umount = selinux_umount,
5461 .sb_set_mnt_opts = selinux_set_mnt_opts,
5462 .sb_clone_mnt_opts = selinux_sb_clone_mnt_opts,
5463 .sb_parse_opts_str = selinux_parse_opts_str,
5464
5465
5466 .inode_alloc_security = selinux_inode_alloc_security,
5467 .inode_free_security = selinux_inode_free_security,
5468 .inode_init_security = selinux_inode_init_security,
5469 .inode_create = selinux_inode_create,
5470 .inode_link = selinux_inode_link,
5471 .inode_unlink = selinux_inode_unlink,
5472 .inode_symlink = selinux_inode_symlink,
5473 .inode_mkdir = selinux_inode_mkdir,
5474 .inode_rmdir = selinux_inode_rmdir,
5475 .inode_mknod = selinux_inode_mknod,
5476 .inode_rename = selinux_inode_rename,
5477 .inode_readlink = selinux_inode_readlink,
5478 .inode_follow_link = selinux_inode_follow_link,
5479 .inode_permission = selinux_inode_permission,
5480 .inode_setattr = selinux_inode_setattr,
5481 .inode_getattr = selinux_inode_getattr,
5482 .inode_setxattr = selinux_inode_setxattr,
5483 .inode_post_setxattr = selinux_inode_post_setxattr,
5484 .inode_getxattr = selinux_inode_getxattr,
5485 .inode_listxattr = selinux_inode_listxattr,
5486 .inode_removexattr = selinux_inode_removexattr,
5487 .inode_getsecurity = selinux_inode_getsecurity,
5488 .inode_setsecurity = selinux_inode_setsecurity,
5489 .inode_listsecurity = selinux_inode_listsecurity,
5490 .inode_getsecid = selinux_inode_getsecid,
5491
5492 .file_permission = selinux_file_permission,
5493 .file_alloc_security = selinux_file_alloc_security,
5494 .file_free_security = selinux_file_free_security,
5495 .file_ioctl = selinux_file_ioctl,
5496 .file_mmap = selinux_file_mmap,
5497 .file_mprotect = selinux_file_mprotect,
5498 .file_lock = selinux_file_lock,
5499 .file_fcntl = selinux_file_fcntl,
5500 .file_set_fowner = selinux_file_set_fowner,
5501 .file_send_sigiotask = selinux_file_send_sigiotask,
5502 .file_receive = selinux_file_receive,
5503
5504 .dentry_open = selinux_dentry_open,
5505
5506 .task_create = selinux_task_create,
5507 .cred_alloc_blank = selinux_cred_alloc_blank,
5508 .cred_free = selinux_cred_free,
5509 .cred_prepare = selinux_cred_prepare,
5510 .cred_transfer = selinux_cred_transfer,
5511 .kernel_act_as = selinux_kernel_act_as,
5512 .kernel_create_files_as = selinux_kernel_create_files_as,
5513 .kernel_module_request = selinux_kernel_module_request,
5514 .task_setpgid = selinux_task_setpgid,
5515 .task_getpgid = selinux_task_getpgid,
5516 .task_getsid = selinux_task_getsid,
5517 .task_getsecid = selinux_task_getsecid,
5518 .task_setnice = selinux_task_setnice,
5519 .task_setioprio = selinux_task_setioprio,
5520 .task_getioprio = selinux_task_getioprio,
5521 .task_setrlimit = selinux_task_setrlimit,
5522 .task_setscheduler = selinux_task_setscheduler,
5523 .task_getscheduler = selinux_task_getscheduler,
5524 .task_movememory = selinux_task_movememory,
5525 .task_kill = selinux_task_kill,
5526 .task_wait = selinux_task_wait,
5527 .task_to_inode = selinux_task_to_inode,
5528
5529 .ipc_permission = selinux_ipc_permission,
5530 .ipc_getsecid = selinux_ipc_getsecid,
5531
5532 .msg_msg_alloc_security = selinux_msg_msg_alloc_security,
5533 .msg_msg_free_security = selinux_msg_msg_free_security,
5534
5535 .msg_queue_alloc_security = selinux_msg_queue_alloc_security,
5536 .msg_queue_free_security = selinux_msg_queue_free_security,
5537 .msg_queue_associate = selinux_msg_queue_associate,
5538 .msg_queue_msgctl = selinux_msg_queue_msgctl,
5539 .msg_queue_msgsnd = selinux_msg_queue_msgsnd,
5540 .msg_queue_msgrcv = selinux_msg_queue_msgrcv,
5541
5542 .shm_alloc_security = selinux_shm_alloc_security,
5543 .shm_free_security = selinux_shm_free_security,
5544 .shm_associate = selinux_shm_associate,
5545 .shm_shmctl = selinux_shm_shmctl,
5546 .shm_shmat = selinux_shm_shmat,
5547
5548 .sem_alloc_security = selinux_sem_alloc_security,
5549 .sem_free_security = selinux_sem_free_security,
5550 .sem_associate = selinux_sem_associate,
5551 .sem_semctl = selinux_sem_semctl,
5552 .sem_semop = selinux_sem_semop,
5553
5554 .d_instantiate = selinux_d_instantiate,
5555
5556 .getprocattr = selinux_getprocattr,
5557 .setprocattr = selinux_setprocattr,
5558
5559 .secid_to_secctx = selinux_secid_to_secctx,
5560 .secctx_to_secid = selinux_secctx_to_secid,
5561 .release_secctx = selinux_release_secctx,
5562 .inode_notifysecctx = selinux_inode_notifysecctx,
5563 .inode_setsecctx = selinux_inode_setsecctx,
5564 .inode_getsecctx = selinux_inode_getsecctx,
5565
5566 .unix_stream_connect = selinux_socket_unix_stream_connect,
5567 .unix_may_send = selinux_socket_unix_may_send,
5568
5569 .socket_create = selinux_socket_create,
5570 .socket_post_create = selinux_socket_post_create,
5571 .socket_bind = selinux_socket_bind,
5572 .socket_connect = selinux_socket_connect,
5573 .socket_listen = selinux_socket_listen,
5574 .socket_accept = selinux_socket_accept,
5575 .socket_sendmsg = selinux_socket_sendmsg,
5576 .socket_recvmsg = selinux_socket_recvmsg,
5577 .socket_getsockname = selinux_socket_getsockname,
5578 .socket_getpeername = selinux_socket_getpeername,
5579 .socket_getsockopt = selinux_socket_getsockopt,
5580 .socket_setsockopt = selinux_socket_setsockopt,
5581 .socket_shutdown = selinux_socket_shutdown,
5582 .socket_sock_rcv_skb = selinux_socket_sock_rcv_skb,
5583 .socket_getpeersec_stream = selinux_socket_getpeersec_stream,
5584 .socket_getpeersec_dgram = selinux_socket_getpeersec_dgram,
5585 .sk_alloc_security = selinux_sk_alloc_security,
5586 .sk_free_security = selinux_sk_free_security,
5587 .sk_clone_security = selinux_sk_clone_security,
5588 .sk_getsecid = selinux_sk_getsecid,
5589 .sock_graft = selinux_sock_graft,
5590 .inet_conn_request = selinux_inet_conn_request,
5591 .inet_csk_clone = selinux_inet_csk_clone,
5592 .inet_conn_established = selinux_inet_conn_established,
5593 .secmark_relabel_packet = selinux_secmark_relabel_packet,
5594 .secmark_refcount_inc = selinux_secmark_refcount_inc,
5595 .secmark_refcount_dec = selinux_secmark_refcount_dec,
5596 .req_classify_flow = selinux_req_classify_flow,
5597 .tun_dev_create = selinux_tun_dev_create,
5598 .tun_dev_post_create = selinux_tun_dev_post_create,
5599 .tun_dev_attach = selinux_tun_dev_attach,
5600
5601 #ifdef CONFIG_SECURITY_NETWORK_XFRM
5602 .xfrm_policy_alloc_security = selinux_xfrm_policy_alloc,
5603 .xfrm_policy_clone_security = selinux_xfrm_policy_clone,
5604 .xfrm_policy_free_security = selinux_xfrm_policy_free,
5605 .xfrm_policy_delete_security = selinux_xfrm_policy_delete,
5606 .xfrm_state_alloc_security = selinux_xfrm_state_alloc,
5607 .xfrm_state_free_security = selinux_xfrm_state_free,
5608 .xfrm_state_delete_security = selinux_xfrm_state_delete,
5609 .xfrm_policy_lookup = selinux_xfrm_policy_lookup,
5610 .xfrm_state_pol_flow_match = selinux_xfrm_state_pol_flow_match,
5611 .xfrm_decode_session = selinux_xfrm_decode_session,
5612 #endif
5613
5614 #ifdef CONFIG_KEYS
5615 .key_alloc = selinux_key_alloc,
5616 .key_free = selinux_key_free,
5617 .key_permission = selinux_key_permission,
5618 .key_getsecurity = selinux_key_getsecurity,
5619 #endif
5620
5621 #ifdef CONFIG_AUDIT
5622 .audit_rule_init = selinux_audit_rule_init,
5623 .audit_rule_known = selinux_audit_rule_known,
5624 .audit_rule_match = selinux_audit_rule_match,
5625 .audit_rule_free = selinux_audit_rule_free,
5626 #endif
5627 };
5628
5629 static __init int selinux_init(void)
5630 {
5631 if (!security_module_enable(&selinux_ops)) {
5632 selinux_enabled = 0;
5633 return 0;
5634 }
5635
5636 if (!selinux_enabled) {
5637 printk(KERN_INFO "SELinux: Disabled at boot.\n");
5638 return 0;
5639 }
5640
5641 printk(KERN_INFO "SELinux: Initializing.\n");
5642
5643 /* Set the security state for the initial task. */
5644 cred_init_security();
5645
5646 default_noexec = !(VM_DATA_DEFAULT_FLAGS & VM_EXEC);
5647
5648 sel_inode_cache = kmem_cache_create("selinux_inode_security",
5649 sizeof(struct inode_security_struct),
5650 0, SLAB_PANIC, NULL);
5651 avc_init();
5652
5653 if (register_security(&selinux_ops))
5654 panic("SELinux: Unable to register with kernel.\n");
5655
5656 if (selinux_enforcing)
5657 printk(KERN_DEBUG "SELinux: Starting in enforcing mode\n");
5658 else
5659 printk(KERN_DEBUG "SELinux: Starting in permissive mode\n");
5660
5661 return 0;
5662 }
5663
5664 static void delayed_superblock_init(struct super_block *sb, void *unused)
5665 {
5666 superblock_doinit(sb, NULL);
5667 }
5668
5669 void selinux_complete_init(void)
5670 {
5671 printk(KERN_DEBUG "SELinux: Completing initialization.\n");
5672
5673 /* Set up any superblocks initialized prior to the policy load. */
5674 printk(KERN_DEBUG "SELinux: Setting up existing superblocks.\n");
5675 iterate_supers(delayed_superblock_init, NULL);
5676 }
5677
5678 /* SELinux requires early initialization in order to label
5679 all processes and objects when they are created. */
5680 security_initcall(selinux_init);
5681
5682 #if defined(CONFIG_NETFILTER)
5683
5684 static struct nf_hook_ops selinux_ipv4_ops[] = {
5685 {
5686 .hook = selinux_ipv4_postroute,
5687 .owner = THIS_MODULE,
5688 .pf = PF_INET,
5689 .hooknum = NF_INET_POST_ROUTING,
5690 .priority = NF_IP_PRI_SELINUX_LAST,
5691 },
5692 {
5693 .hook = selinux_ipv4_forward,
5694 .owner = THIS_MODULE,
5695 .pf = PF_INET,
5696 .hooknum = NF_INET_FORWARD,
5697 .priority = NF_IP_PRI_SELINUX_FIRST,
5698 },
5699 {
5700 .hook = selinux_ipv4_output,
5701 .owner = THIS_MODULE,
5702 .pf = PF_INET,
5703 .hooknum = NF_INET_LOCAL_OUT,
5704 .priority = NF_IP_PRI_SELINUX_FIRST,
5705 }
5706 };
5707
5708 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
5709
5710 static struct nf_hook_ops selinux_ipv6_ops[] = {
5711 {
5712 .hook = selinux_ipv6_postroute,
5713 .owner = THIS_MODULE,
5714 .pf = PF_INET6,
5715 .hooknum = NF_INET_POST_ROUTING,
5716 .priority = NF_IP6_PRI_SELINUX_LAST,
5717 },
5718 {
5719 .hook = selinux_ipv6_forward,
5720 .owner = THIS_MODULE,
5721 .pf = PF_INET6,
5722 .hooknum = NF_INET_FORWARD,
5723 .priority = NF_IP6_PRI_SELINUX_FIRST,
5724 }
5725 };
5726
5727 #endif /* IPV6 */
5728
5729 static int __init selinux_nf_ip_init(void)
5730 {
5731 int err = 0;
5732
5733 if (!selinux_enabled)
5734 goto out;
5735
5736 printk(KERN_DEBUG "SELinux: Registering netfilter hooks\n");
5737
5738 err = nf_register_hooks(selinux_ipv4_ops, ARRAY_SIZE(selinux_ipv4_ops));
5739 if (err)
5740 panic("SELinux: nf_register_hooks for IPv4: error %d\n", err);
5741
5742 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
5743 err = nf_register_hooks(selinux_ipv6_ops, ARRAY_SIZE(selinux_ipv6_ops));
5744 if (err)
5745 panic("SELinux: nf_register_hooks for IPv6: error %d\n", err);
5746 #endif /* IPV6 */
5747
5748 out:
5749 return err;
5750 }
5751
5752 __initcall(selinux_nf_ip_init);
5753
5754 #ifdef CONFIG_SECURITY_SELINUX_DISABLE
5755 static void selinux_nf_ip_exit(void)
5756 {
5757 printk(KERN_DEBUG "SELinux: Unregistering netfilter hooks\n");
5758
5759 nf_unregister_hooks(selinux_ipv4_ops, ARRAY_SIZE(selinux_ipv4_ops));
5760 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
5761 nf_unregister_hooks(selinux_ipv6_ops, ARRAY_SIZE(selinux_ipv6_ops));
5762 #endif /* IPV6 */
5763 }
5764 #endif
5765
5766 #else /* CONFIG_NETFILTER */
5767
5768 #ifdef CONFIG_SECURITY_SELINUX_DISABLE
5769 #define selinux_nf_ip_exit()
5770 #endif
5771
5772 #endif /* CONFIG_NETFILTER */
5773
5774 #ifdef CONFIG_SECURITY_SELINUX_DISABLE
5775 static int selinux_disabled;
5776
5777 int selinux_disable(void)
5778 {
5779 if (ss_initialized) {
5780 /* Not permitted after initial policy load. */
5781 return -EINVAL;
5782 }
5783
5784 if (selinux_disabled) {
5785 /* Only do this once. */
5786 return -EINVAL;
5787 }
5788
5789 printk(KERN_INFO "SELinux: Disabled at runtime.\n");
5790
5791 selinux_disabled = 1;
5792 selinux_enabled = 0;
5793
5794 reset_security_ops();
5795
5796 /* Try to destroy the avc node cache */
5797 avc_disable();
5798
5799 /* Unregister netfilter hooks. */
5800 selinux_nf_ip_exit();
5801
5802 /* Unregister selinuxfs. */
5803 exit_sel_fs();
5804
5805 return 0;
5806 }
5807 #endif