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Fix 'ALIGN()' macro, take 2
[net-next-2.6.git] / security / selinux / hooks.c
CommitLineData
1da177e4
LT
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 Red Hat, Inc., James Morris <jmorris@redhat.com>
13 * Copyright (C) 2004-2005 Trusted Computer Solutions, Inc.
14 * <dgoeddel@trustedcs.com>
7420ed23
VY
15 * Copyright (C) 2006 Hewlett-Packard Development Company, L.P.
16 * Paul Moore, <paul.moore@hp.com>
1da177e4
LT
17 *
18 * This program is free software; you can redistribute it and/or modify
19 * it under the terms of the GNU General Public License version 2,
20 * as published by the Free Software Foundation.
21 */
22
1da177e4
LT
23#include <linux/module.h>
24#include <linux/init.h>
25#include <linux/kernel.h>
26#include <linux/ptrace.h>
27#include <linux/errno.h>
28#include <linux/sched.h>
29#include <linux/security.h>
30#include <linux/xattr.h>
31#include <linux/capability.h>
32#include <linux/unistd.h>
33#include <linux/mm.h>
34#include <linux/mman.h>
35#include <linux/slab.h>
36#include <linux/pagemap.h>
37#include <linux/swap.h>
38#include <linux/smp_lock.h>
39#include <linux/spinlock.h>
40#include <linux/syscalls.h>
41#include <linux/file.h>
42#include <linux/namei.h>
43#include <linux/mount.h>
44#include <linux/ext2_fs.h>
45#include <linux/proc_fs.h>
46#include <linux/kd.h>
47#include <linux/netfilter_ipv4.h>
48#include <linux/netfilter_ipv6.h>
49#include <linux/tty.h>
50#include <net/icmp.h>
51#include <net/ip.h> /* for sysctl_local_port_range[] */
52#include <net/tcp.h> /* struct or_callable used in sock_rcv_skb */
53#include <asm/uaccess.h>
1da177e4
LT
54#include <asm/ioctls.h>
55#include <linux/bitops.h>
56#include <linux/interrupt.h>
57#include <linux/netdevice.h> /* for network interface checks */
58#include <linux/netlink.h>
59#include <linux/tcp.h>
60#include <linux/udp.h>
61#include <linux/quota.h>
62#include <linux/un.h> /* for Unix socket types */
63#include <net/af_unix.h> /* for Unix socket types */
64#include <linux/parser.h>
65#include <linux/nfs_mount.h>
66#include <net/ipv6.h>
67#include <linux/hugetlb.h>
68#include <linux/personality.h>
69#include <linux/sysctl.h>
70#include <linux/audit.h>
6931dfc9 71#include <linux/string.h>
877ce7c1 72#include <linux/selinux.h>
23970741 73#include <linux/mutex.h>
1da177e4
LT
74
75#include "avc.h"
76#include "objsec.h"
77#include "netif.h"
d28d1e08 78#include "xfrm.h"
7420ed23 79#include "selinux_netlabel.h"
1da177e4
LT
80
81#define XATTR_SELINUX_SUFFIX "selinux"
82#define XATTR_NAME_SELINUX XATTR_SECURITY_PREFIX XATTR_SELINUX_SUFFIX
83
84extern unsigned int policydb_loaded_version;
85extern int selinux_nlmsg_lookup(u16 sclass, u16 nlmsg_type, u32 *perm);
4e5ab4cb 86extern int selinux_compat_net;
1da177e4
LT
87
88#ifdef CONFIG_SECURITY_SELINUX_DEVELOP
89int selinux_enforcing = 0;
90
91static int __init enforcing_setup(char *str)
92{
93 selinux_enforcing = simple_strtol(str,NULL,0);
94 return 1;
95}
96__setup("enforcing=", enforcing_setup);
97#endif
98
99#ifdef CONFIG_SECURITY_SELINUX_BOOTPARAM
100int selinux_enabled = CONFIG_SECURITY_SELINUX_BOOTPARAM_VALUE;
101
102static int __init selinux_enabled_setup(char *str)
103{
104 selinux_enabled = simple_strtol(str, NULL, 0);
105 return 1;
106}
107__setup("selinux=", selinux_enabled_setup);
30d55280
SS
108#else
109int selinux_enabled = 1;
1da177e4
LT
110#endif
111
112/* Original (dummy) security module. */
113static struct security_operations *original_ops = NULL;
114
115/* Minimal support for a secondary security module,
116 just to allow the use of the dummy or capability modules.
117 The owlsm module can alternatively be used as a secondary
118 module as long as CONFIG_OWLSM_FD is not enabled. */
119static struct security_operations *secondary_ops = NULL;
120
121/* Lists of inode and superblock security structures initialized
122 before the policy was loaded. */
123static LIST_HEAD(superblock_security_head);
124static DEFINE_SPINLOCK(sb_security_lock);
125
7cae7e26
JM
126static kmem_cache_t *sel_inode_cache;
127
8c8570fb
DK
128/* Return security context for a given sid or just the context
129 length if the buffer is null or length is 0 */
130static int selinux_getsecurity(u32 sid, void *buffer, size_t size)
131{
132 char *context;
133 unsigned len;
134 int rc;
135
136 rc = security_sid_to_context(sid, &context, &len);
137 if (rc)
138 return rc;
139
140 if (!buffer || !size)
141 goto getsecurity_exit;
142
143 if (size < len) {
144 len = -ERANGE;
145 goto getsecurity_exit;
146 }
147 memcpy(buffer, context, len);
148
149getsecurity_exit:
150 kfree(context);
151 return len;
152}
153
1da177e4
LT
154/* Allocate and free functions for each kind of security blob. */
155
156static int task_alloc_security(struct task_struct *task)
157{
158 struct task_security_struct *tsec;
159
89d155ef 160 tsec = kzalloc(sizeof(struct task_security_struct), GFP_KERNEL);
1da177e4
LT
161 if (!tsec)
162 return -ENOMEM;
163
1da177e4
LT
164 tsec->task = task;
165 tsec->osid = tsec->sid = tsec->ptrace_sid = SECINITSID_UNLABELED;
166 task->security = tsec;
167
168 return 0;
169}
170
171static void task_free_security(struct task_struct *task)
172{
173 struct task_security_struct *tsec = task->security;
1da177e4
LT
174 task->security = NULL;
175 kfree(tsec);
176}
177
178static int inode_alloc_security(struct inode *inode)
179{
180 struct task_security_struct *tsec = current->security;
181 struct inode_security_struct *isec;
182
7cae7e26 183 isec = kmem_cache_alloc(sel_inode_cache, SLAB_KERNEL);
1da177e4
LT
184 if (!isec)
185 return -ENOMEM;
186
7cae7e26 187 memset(isec, 0, sizeof(*isec));
23970741 188 mutex_init(&isec->lock);
1da177e4 189 INIT_LIST_HEAD(&isec->list);
1da177e4
LT
190 isec->inode = inode;
191 isec->sid = SECINITSID_UNLABELED;
192 isec->sclass = SECCLASS_FILE;
9ac49d22 193 isec->task_sid = tsec->sid;
1da177e4
LT
194 inode->i_security = isec;
195
196 return 0;
197}
198
199static void inode_free_security(struct inode *inode)
200{
201 struct inode_security_struct *isec = inode->i_security;
202 struct superblock_security_struct *sbsec = inode->i_sb->s_security;
203
1da177e4
LT
204 spin_lock(&sbsec->isec_lock);
205 if (!list_empty(&isec->list))
206 list_del_init(&isec->list);
207 spin_unlock(&sbsec->isec_lock);
208
209 inode->i_security = NULL;
7cae7e26 210 kmem_cache_free(sel_inode_cache, isec);
1da177e4
LT
211}
212
213static int file_alloc_security(struct file *file)
214{
215 struct task_security_struct *tsec = current->security;
216 struct file_security_struct *fsec;
217
26d2a4be 218 fsec = kzalloc(sizeof(struct file_security_struct), GFP_KERNEL);
1da177e4
LT
219 if (!fsec)
220 return -ENOMEM;
221
1da177e4 222 fsec->file = file;
9ac49d22
SS
223 fsec->sid = tsec->sid;
224 fsec->fown_sid = tsec->sid;
1da177e4
LT
225 file->f_security = fsec;
226
227 return 0;
228}
229
230static void file_free_security(struct file *file)
231{
232 struct file_security_struct *fsec = file->f_security;
1da177e4
LT
233 file->f_security = NULL;
234 kfree(fsec);
235}
236
237static int superblock_alloc_security(struct super_block *sb)
238{
239 struct superblock_security_struct *sbsec;
240
89d155ef 241 sbsec = kzalloc(sizeof(struct superblock_security_struct), GFP_KERNEL);
1da177e4
LT
242 if (!sbsec)
243 return -ENOMEM;
244
bc7e982b 245 mutex_init(&sbsec->lock);
1da177e4
LT
246 INIT_LIST_HEAD(&sbsec->list);
247 INIT_LIST_HEAD(&sbsec->isec_head);
248 spin_lock_init(&sbsec->isec_lock);
1da177e4
LT
249 sbsec->sb = sb;
250 sbsec->sid = SECINITSID_UNLABELED;
251 sbsec->def_sid = SECINITSID_FILE;
c312feb2 252 sbsec->mntpoint_sid = SECINITSID_UNLABELED;
1da177e4
LT
253 sb->s_security = sbsec;
254
255 return 0;
256}
257
258static void superblock_free_security(struct super_block *sb)
259{
260 struct superblock_security_struct *sbsec = sb->s_security;
261
1da177e4
LT
262 spin_lock(&sb_security_lock);
263 if (!list_empty(&sbsec->list))
264 list_del_init(&sbsec->list);
265 spin_unlock(&sb_security_lock);
266
267 sb->s_security = NULL;
268 kfree(sbsec);
269}
270
7d877f3b 271static int sk_alloc_security(struct sock *sk, int family, gfp_t priority)
1da177e4
LT
272{
273 struct sk_security_struct *ssec;
274
89d155ef 275 ssec = kzalloc(sizeof(*ssec), priority);
1da177e4
LT
276 if (!ssec)
277 return -ENOMEM;
278
1da177e4
LT
279 ssec->sk = sk;
280 ssec->peer_sid = SECINITSID_UNLABELED;
892c141e 281 ssec->sid = SECINITSID_UNLABELED;
1da177e4
LT
282 sk->sk_security = ssec;
283
99f59ed0
PM
284 selinux_netlbl_sk_security_init(ssec, family);
285
1da177e4
LT
286 return 0;
287}
288
289static void sk_free_security(struct sock *sk)
290{
291 struct sk_security_struct *ssec = sk->sk_security;
292
1da177e4
LT
293 sk->sk_security = NULL;
294 kfree(ssec);
295}
1da177e4
LT
296
297/* The security server must be initialized before
298 any labeling or access decisions can be provided. */
299extern int ss_initialized;
300
301/* The file system's label must be initialized prior to use. */
302
303static char *labeling_behaviors[6] = {
304 "uses xattr",
305 "uses transition SIDs",
306 "uses task SIDs",
307 "uses genfs_contexts",
308 "not configured for labeling",
309 "uses mountpoint labeling",
310};
311
312static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dentry);
313
314static inline int inode_doinit(struct inode *inode)
315{
316 return inode_doinit_with_dentry(inode, NULL);
317}
318
319enum {
320 Opt_context = 1,
321 Opt_fscontext = 2,
322 Opt_defcontext = 4,
0808925e 323 Opt_rootcontext = 8,
1da177e4
LT
324};
325
326static match_table_t tokens = {
327 {Opt_context, "context=%s"},
328 {Opt_fscontext, "fscontext=%s"},
329 {Opt_defcontext, "defcontext=%s"},
0808925e 330 {Opt_rootcontext, "rootcontext=%s"},
1da177e4
LT
331};
332
333#define SEL_MOUNT_FAIL_MSG "SELinux: duplicate or incompatible mount options\n"
334
c312feb2
EP
335static int may_context_mount_sb_relabel(u32 sid,
336 struct superblock_security_struct *sbsec,
337 struct task_security_struct *tsec)
338{
339 int rc;
340
341 rc = avc_has_perm(tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM,
342 FILESYSTEM__RELABELFROM, NULL);
343 if (rc)
344 return rc;
345
346 rc = avc_has_perm(tsec->sid, sid, SECCLASS_FILESYSTEM,
347 FILESYSTEM__RELABELTO, NULL);
348 return rc;
349}
350
0808925e
EP
351static int may_context_mount_inode_relabel(u32 sid,
352 struct superblock_security_struct *sbsec,
353 struct task_security_struct *tsec)
354{
355 int rc;
356 rc = avc_has_perm(tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM,
357 FILESYSTEM__RELABELFROM, NULL);
358 if (rc)
359 return rc;
360
361 rc = avc_has_perm(sid, sbsec->sid, SECCLASS_FILESYSTEM,
362 FILESYSTEM__ASSOCIATE, NULL);
363 return rc;
364}
365
1da177e4
LT
366static int try_context_mount(struct super_block *sb, void *data)
367{
368 char *context = NULL, *defcontext = NULL;
0808925e 369 char *fscontext = NULL, *rootcontext = NULL;
1da177e4
LT
370 const char *name;
371 u32 sid;
372 int alloc = 0, rc = 0, seen = 0;
373 struct task_security_struct *tsec = current->security;
374 struct superblock_security_struct *sbsec = sb->s_security;
375
376 if (!data)
377 goto out;
378
379 name = sb->s_type->name;
380
381 if (sb->s_type->fs_flags & FS_BINARY_MOUNTDATA) {
382
383 /* NFS we understand. */
384 if (!strcmp(name, "nfs")) {
385 struct nfs_mount_data *d = data;
386
387 if (d->version < NFS_MOUNT_VERSION)
388 goto out;
389
390 if (d->context[0]) {
391 context = d->context;
392 seen |= Opt_context;
393 }
394 } else
395 goto out;
396
397 } else {
398 /* Standard string-based options. */
399 char *p, *options = data;
400
3528a953 401 while ((p = strsep(&options, "|")) != NULL) {
1da177e4
LT
402 int token;
403 substring_t args[MAX_OPT_ARGS];
404
405 if (!*p)
406 continue;
407
408 token = match_token(p, tokens, args);
409
410 switch (token) {
411 case Opt_context:
c312feb2 412 if (seen & (Opt_context|Opt_defcontext)) {
1da177e4
LT
413 rc = -EINVAL;
414 printk(KERN_WARNING SEL_MOUNT_FAIL_MSG);
415 goto out_free;
416 }
417 context = match_strdup(&args[0]);
418 if (!context) {
419 rc = -ENOMEM;
420 goto out_free;
421 }
422 if (!alloc)
423 alloc = 1;
424 seen |= Opt_context;
425 break;
426
427 case Opt_fscontext:
c312feb2 428 if (seen & Opt_fscontext) {
1da177e4
LT
429 rc = -EINVAL;
430 printk(KERN_WARNING SEL_MOUNT_FAIL_MSG);
431 goto out_free;
432 }
c312feb2
EP
433 fscontext = match_strdup(&args[0]);
434 if (!fscontext) {
1da177e4
LT
435 rc = -ENOMEM;
436 goto out_free;
437 }
438 if (!alloc)
439 alloc = 1;
440 seen |= Opt_fscontext;
441 break;
442
0808925e
EP
443 case Opt_rootcontext:
444 if (seen & Opt_rootcontext) {
445 rc = -EINVAL;
446 printk(KERN_WARNING SEL_MOUNT_FAIL_MSG);
447 goto out_free;
448 }
449 rootcontext = match_strdup(&args[0]);
450 if (!rootcontext) {
451 rc = -ENOMEM;
452 goto out_free;
453 }
454 if (!alloc)
455 alloc = 1;
456 seen |= Opt_rootcontext;
457 break;
458
1da177e4
LT
459 case Opt_defcontext:
460 if (sbsec->behavior != SECURITY_FS_USE_XATTR) {
461 rc = -EINVAL;
462 printk(KERN_WARNING "SELinux: "
463 "defcontext option is invalid "
464 "for this filesystem type\n");
465 goto out_free;
466 }
467 if (seen & (Opt_context|Opt_defcontext)) {
468 rc = -EINVAL;
469 printk(KERN_WARNING SEL_MOUNT_FAIL_MSG);
470 goto out_free;
471 }
472 defcontext = match_strdup(&args[0]);
473 if (!defcontext) {
474 rc = -ENOMEM;
475 goto out_free;
476 }
477 if (!alloc)
478 alloc = 1;
479 seen |= Opt_defcontext;
480 break;
481
482 default:
483 rc = -EINVAL;
484 printk(KERN_WARNING "SELinux: unknown mount "
485 "option\n");
486 goto out_free;
487
488 }
489 }
490 }
491
492 if (!seen)
493 goto out;
494
c312feb2
EP
495 /* sets the context of the superblock for the fs being mounted. */
496 if (fscontext) {
497 rc = security_context_to_sid(fscontext, strlen(fscontext), &sid);
1da177e4
LT
498 if (rc) {
499 printk(KERN_WARNING "SELinux: security_context_to_sid"
500 "(%s) failed for (dev %s, type %s) errno=%d\n",
c312feb2 501 fscontext, sb->s_id, name, rc);
1da177e4
LT
502 goto out_free;
503 }
504
c312feb2 505 rc = may_context_mount_sb_relabel(sid, sbsec, tsec);
1da177e4
LT
506 if (rc)
507 goto out_free;
508
c312feb2
EP
509 sbsec->sid = sid;
510 }
511
512 /*
513 * Switch to using mount point labeling behavior.
514 * sets the label used on all file below the mountpoint, and will set
515 * the superblock context if not already set.
516 */
517 if (context) {
518 rc = security_context_to_sid(context, strlen(context), &sid);
519 if (rc) {
520 printk(KERN_WARNING "SELinux: security_context_to_sid"
521 "(%s) failed for (dev %s, type %s) errno=%d\n",
522 context, sb->s_id, name, rc);
523 goto out_free;
524 }
525
b04ea3ce
EP
526 if (!fscontext) {
527 rc = may_context_mount_sb_relabel(sid, sbsec, tsec);
528 if (rc)
529 goto out_free;
c312feb2 530 sbsec->sid = sid;
b04ea3ce
EP
531 } else {
532 rc = may_context_mount_inode_relabel(sid, sbsec, tsec);
533 if (rc)
534 goto out_free;
535 }
c312feb2 536 sbsec->mntpoint_sid = sid;
1da177e4 537
c312feb2 538 sbsec->behavior = SECURITY_FS_USE_MNTPOINT;
1da177e4
LT
539 }
540
0808925e
EP
541 if (rootcontext) {
542 struct inode *inode = sb->s_root->d_inode;
543 struct inode_security_struct *isec = inode->i_security;
544 rc = security_context_to_sid(rootcontext, strlen(rootcontext), &sid);
545 if (rc) {
546 printk(KERN_WARNING "SELinux: security_context_to_sid"
547 "(%s) failed for (dev %s, type %s) errno=%d\n",
548 rootcontext, sb->s_id, name, rc);
549 goto out_free;
550 }
551
552 rc = may_context_mount_inode_relabel(sid, sbsec, tsec);
553 if (rc)
554 goto out_free;
555
556 isec->sid = sid;
557 isec->initialized = 1;
558 }
559
1da177e4
LT
560 if (defcontext) {
561 rc = security_context_to_sid(defcontext, strlen(defcontext), &sid);
562 if (rc) {
563 printk(KERN_WARNING "SELinux: security_context_to_sid"
564 "(%s) failed for (dev %s, type %s) errno=%d\n",
565 defcontext, sb->s_id, name, rc);
566 goto out_free;
567 }
568
569 if (sid == sbsec->def_sid)
570 goto out_free;
571
0808925e 572 rc = may_context_mount_inode_relabel(sid, sbsec, tsec);
1da177e4
LT
573 if (rc)
574 goto out_free;
575
576 sbsec->def_sid = sid;
577 }
578
579out_free:
580 if (alloc) {
581 kfree(context);
582 kfree(defcontext);
c312feb2 583 kfree(fscontext);
0808925e 584 kfree(rootcontext);
1da177e4
LT
585 }
586out:
587 return rc;
588}
589
590static int superblock_doinit(struct super_block *sb, void *data)
591{
592 struct superblock_security_struct *sbsec = sb->s_security;
593 struct dentry *root = sb->s_root;
594 struct inode *inode = root->d_inode;
595 int rc = 0;
596
bc7e982b 597 mutex_lock(&sbsec->lock);
1da177e4
LT
598 if (sbsec->initialized)
599 goto out;
600
601 if (!ss_initialized) {
602 /* Defer initialization until selinux_complete_init,
603 after the initial policy is loaded and the security
604 server is ready to handle calls. */
605 spin_lock(&sb_security_lock);
606 if (list_empty(&sbsec->list))
607 list_add(&sbsec->list, &superblock_security_head);
608 spin_unlock(&sb_security_lock);
609 goto out;
610 }
611
612 /* Determine the labeling behavior to use for this filesystem type. */
613 rc = security_fs_use(sb->s_type->name, &sbsec->behavior, &sbsec->sid);
614 if (rc) {
615 printk(KERN_WARNING "%s: security_fs_use(%s) returned %d\n",
616 __FUNCTION__, sb->s_type->name, rc);
617 goto out;
618 }
619
620 rc = try_context_mount(sb, data);
621 if (rc)
622 goto out;
623
624 if (sbsec->behavior == SECURITY_FS_USE_XATTR) {
625 /* Make sure that the xattr handler exists and that no
626 error other than -ENODATA is returned by getxattr on
627 the root directory. -ENODATA is ok, as this may be
628 the first boot of the SELinux kernel before we have
629 assigned xattr values to the filesystem. */
630 if (!inode->i_op->getxattr) {
631 printk(KERN_WARNING "SELinux: (dev %s, type %s) has no "
632 "xattr support\n", sb->s_id, sb->s_type->name);
633 rc = -EOPNOTSUPP;
634 goto out;
635 }
636 rc = inode->i_op->getxattr(root, XATTR_NAME_SELINUX, NULL, 0);
637 if (rc < 0 && rc != -ENODATA) {
638 if (rc == -EOPNOTSUPP)
639 printk(KERN_WARNING "SELinux: (dev %s, type "
640 "%s) has no security xattr handler\n",
641 sb->s_id, sb->s_type->name);
642 else
643 printk(KERN_WARNING "SELinux: (dev %s, type "
644 "%s) getxattr errno %d\n", sb->s_id,
645 sb->s_type->name, -rc);
646 goto out;
647 }
648 }
649
650 if (strcmp(sb->s_type->name, "proc") == 0)
651 sbsec->proc = 1;
652
653 sbsec->initialized = 1;
654
655 if (sbsec->behavior > ARRAY_SIZE(labeling_behaviors)) {
656 printk(KERN_INFO "SELinux: initialized (dev %s, type %s), unknown behavior\n",
657 sb->s_id, sb->s_type->name);
658 }
659 else {
660 printk(KERN_INFO "SELinux: initialized (dev %s, type %s), %s\n",
661 sb->s_id, sb->s_type->name,
662 labeling_behaviors[sbsec->behavior-1]);
663 }
664
665 /* Initialize the root inode. */
666 rc = inode_doinit_with_dentry(sb->s_root->d_inode, sb->s_root);
667
668 /* Initialize any other inodes associated with the superblock, e.g.
669 inodes created prior to initial policy load or inodes created
670 during get_sb by a pseudo filesystem that directly
671 populates itself. */
672 spin_lock(&sbsec->isec_lock);
673next_inode:
674 if (!list_empty(&sbsec->isec_head)) {
675 struct inode_security_struct *isec =
676 list_entry(sbsec->isec_head.next,
677 struct inode_security_struct, list);
678 struct inode *inode = isec->inode;
679 spin_unlock(&sbsec->isec_lock);
680 inode = igrab(inode);
681 if (inode) {
682 if (!IS_PRIVATE (inode))
683 inode_doinit(inode);
684 iput(inode);
685 }
686 spin_lock(&sbsec->isec_lock);
687 list_del_init(&isec->list);
688 goto next_inode;
689 }
690 spin_unlock(&sbsec->isec_lock);
691out:
bc7e982b 692 mutex_unlock(&sbsec->lock);
1da177e4
LT
693 return rc;
694}
695
696static inline u16 inode_mode_to_security_class(umode_t mode)
697{
698 switch (mode & S_IFMT) {
699 case S_IFSOCK:
700 return SECCLASS_SOCK_FILE;
701 case S_IFLNK:
702 return SECCLASS_LNK_FILE;
703 case S_IFREG:
704 return SECCLASS_FILE;
705 case S_IFBLK:
706 return SECCLASS_BLK_FILE;
707 case S_IFDIR:
708 return SECCLASS_DIR;
709 case S_IFCHR:
710 return SECCLASS_CHR_FILE;
711 case S_IFIFO:
712 return SECCLASS_FIFO_FILE;
713
714 }
715
716 return SECCLASS_FILE;
717}
718
13402580
JM
719static inline int default_protocol_stream(int protocol)
720{
721 return (protocol == IPPROTO_IP || protocol == IPPROTO_TCP);
722}
723
724static inline int default_protocol_dgram(int protocol)
725{
726 return (protocol == IPPROTO_IP || protocol == IPPROTO_UDP);
727}
728
1da177e4
LT
729static inline u16 socket_type_to_security_class(int family, int type, int protocol)
730{
731 switch (family) {
732 case PF_UNIX:
733 switch (type) {
734 case SOCK_STREAM:
735 case SOCK_SEQPACKET:
736 return SECCLASS_UNIX_STREAM_SOCKET;
737 case SOCK_DGRAM:
738 return SECCLASS_UNIX_DGRAM_SOCKET;
739 }
740 break;
741 case PF_INET:
742 case PF_INET6:
743 switch (type) {
744 case SOCK_STREAM:
13402580
JM
745 if (default_protocol_stream(protocol))
746 return SECCLASS_TCP_SOCKET;
747 else
748 return SECCLASS_RAWIP_SOCKET;
1da177e4 749 case SOCK_DGRAM:
13402580
JM
750 if (default_protocol_dgram(protocol))
751 return SECCLASS_UDP_SOCKET;
752 else
753 return SECCLASS_RAWIP_SOCKET;
754 default:
1da177e4
LT
755 return SECCLASS_RAWIP_SOCKET;
756 }
757 break;
758 case PF_NETLINK:
759 switch (protocol) {
760 case NETLINK_ROUTE:
761 return SECCLASS_NETLINK_ROUTE_SOCKET;
762 case NETLINK_FIREWALL:
763 return SECCLASS_NETLINK_FIREWALL_SOCKET;
216efaaa 764 case NETLINK_INET_DIAG:
1da177e4
LT
765 return SECCLASS_NETLINK_TCPDIAG_SOCKET;
766 case NETLINK_NFLOG:
767 return SECCLASS_NETLINK_NFLOG_SOCKET;
768 case NETLINK_XFRM:
769 return SECCLASS_NETLINK_XFRM_SOCKET;
770 case NETLINK_SELINUX:
771 return SECCLASS_NETLINK_SELINUX_SOCKET;
772 case NETLINK_AUDIT:
773 return SECCLASS_NETLINK_AUDIT_SOCKET;
774 case NETLINK_IP6_FW:
775 return SECCLASS_NETLINK_IP6FW_SOCKET;
776 case NETLINK_DNRTMSG:
777 return SECCLASS_NETLINK_DNRT_SOCKET;
0c9b7942
JM
778 case NETLINK_KOBJECT_UEVENT:
779 return SECCLASS_NETLINK_KOBJECT_UEVENT_SOCKET;
1da177e4
LT
780 default:
781 return SECCLASS_NETLINK_SOCKET;
782 }
783 case PF_PACKET:
784 return SECCLASS_PACKET_SOCKET;
785 case PF_KEY:
786 return SECCLASS_KEY_SOCKET;
3e3ff15e
CP
787 case PF_APPLETALK:
788 return SECCLASS_APPLETALK_SOCKET;
1da177e4
LT
789 }
790
791 return SECCLASS_SOCKET;
792}
793
794#ifdef CONFIG_PROC_FS
795static int selinux_proc_get_sid(struct proc_dir_entry *de,
796 u16 tclass,
797 u32 *sid)
798{
799 int buflen, rc;
800 char *buffer, *path, *end;
801
802 buffer = (char*)__get_free_page(GFP_KERNEL);
803 if (!buffer)
804 return -ENOMEM;
805
806 buflen = PAGE_SIZE;
807 end = buffer+buflen;
808 *--end = '\0';
809 buflen--;
810 path = end-1;
811 *path = '/';
812 while (de && de != de->parent) {
813 buflen -= de->namelen + 1;
814 if (buflen < 0)
815 break;
816 end -= de->namelen;
817 memcpy(end, de->name, de->namelen);
818 *--end = '/';
819 path = end;
820 de = de->parent;
821 }
822 rc = security_genfs_sid("proc", path, tclass, sid);
823 free_page((unsigned long)buffer);
824 return rc;
825}
826#else
827static int selinux_proc_get_sid(struct proc_dir_entry *de,
828 u16 tclass,
829 u32 *sid)
830{
831 return -EINVAL;
832}
833#endif
834
835/* The inode's security attributes must be initialized before first use. */
836static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dentry)
837{
838 struct superblock_security_struct *sbsec = NULL;
839 struct inode_security_struct *isec = inode->i_security;
840 u32 sid;
841 struct dentry *dentry;
842#define INITCONTEXTLEN 255
843 char *context = NULL;
844 unsigned len = 0;
845 int rc = 0;
1da177e4
LT
846
847 if (isec->initialized)
848 goto out;
849
23970741 850 mutex_lock(&isec->lock);
1da177e4 851 if (isec->initialized)
23970741 852 goto out_unlock;
1da177e4
LT
853
854 sbsec = inode->i_sb->s_security;
855 if (!sbsec->initialized) {
856 /* Defer initialization until selinux_complete_init,
857 after the initial policy is loaded and the security
858 server is ready to handle calls. */
859 spin_lock(&sbsec->isec_lock);
860 if (list_empty(&isec->list))
861 list_add(&isec->list, &sbsec->isec_head);
862 spin_unlock(&sbsec->isec_lock);
23970741 863 goto out_unlock;
1da177e4
LT
864 }
865
866 switch (sbsec->behavior) {
867 case SECURITY_FS_USE_XATTR:
868 if (!inode->i_op->getxattr) {
869 isec->sid = sbsec->def_sid;
870 break;
871 }
872
873 /* Need a dentry, since the xattr API requires one.
874 Life would be simpler if we could just pass the inode. */
875 if (opt_dentry) {
876 /* Called from d_instantiate or d_splice_alias. */
877 dentry = dget(opt_dentry);
878 } else {
879 /* Called from selinux_complete_init, try to find a dentry. */
880 dentry = d_find_alias(inode);
881 }
882 if (!dentry) {
883 printk(KERN_WARNING "%s: no dentry for dev=%s "
884 "ino=%ld\n", __FUNCTION__, inode->i_sb->s_id,
885 inode->i_ino);
23970741 886 goto out_unlock;
1da177e4
LT
887 }
888
889 len = INITCONTEXTLEN;
890 context = kmalloc(len, GFP_KERNEL);
891 if (!context) {
892 rc = -ENOMEM;
893 dput(dentry);
23970741 894 goto out_unlock;
1da177e4
LT
895 }
896 rc = inode->i_op->getxattr(dentry, XATTR_NAME_SELINUX,
897 context, len);
898 if (rc == -ERANGE) {
899 /* Need a larger buffer. Query for the right size. */
900 rc = inode->i_op->getxattr(dentry, XATTR_NAME_SELINUX,
901 NULL, 0);
902 if (rc < 0) {
903 dput(dentry);
23970741 904 goto out_unlock;
1da177e4
LT
905 }
906 kfree(context);
907 len = rc;
908 context = kmalloc(len, GFP_KERNEL);
909 if (!context) {
910 rc = -ENOMEM;
911 dput(dentry);
23970741 912 goto out_unlock;
1da177e4
LT
913 }
914 rc = inode->i_op->getxattr(dentry,
915 XATTR_NAME_SELINUX,
916 context, len);
917 }
918 dput(dentry);
919 if (rc < 0) {
920 if (rc != -ENODATA) {
921 printk(KERN_WARNING "%s: getxattr returned "
922 "%d for dev=%s ino=%ld\n", __FUNCTION__,
923 -rc, inode->i_sb->s_id, inode->i_ino);
924 kfree(context);
23970741 925 goto out_unlock;
1da177e4
LT
926 }
927 /* Map ENODATA to the default file SID */
928 sid = sbsec->def_sid;
929 rc = 0;
930 } else {
f5c1d5b2
JM
931 rc = security_context_to_sid_default(context, rc, &sid,
932 sbsec->def_sid);
1da177e4
LT
933 if (rc) {
934 printk(KERN_WARNING "%s: context_to_sid(%s) "
935 "returned %d for dev=%s ino=%ld\n",
936 __FUNCTION__, context, -rc,
937 inode->i_sb->s_id, inode->i_ino);
938 kfree(context);
939 /* Leave with the unlabeled SID */
940 rc = 0;
941 break;
942 }
943 }
944 kfree(context);
945 isec->sid = sid;
946 break;
947 case SECURITY_FS_USE_TASK:
948 isec->sid = isec->task_sid;
949 break;
950 case SECURITY_FS_USE_TRANS:
951 /* Default to the fs SID. */
952 isec->sid = sbsec->sid;
953
954 /* Try to obtain a transition SID. */
955 isec->sclass = inode_mode_to_security_class(inode->i_mode);
956 rc = security_transition_sid(isec->task_sid,
957 sbsec->sid,
958 isec->sclass,
959 &sid);
960 if (rc)
23970741 961 goto out_unlock;
1da177e4
LT
962 isec->sid = sid;
963 break;
c312feb2
EP
964 case SECURITY_FS_USE_MNTPOINT:
965 isec->sid = sbsec->mntpoint_sid;
966 break;
1da177e4 967 default:
c312feb2 968 /* Default to the fs superblock SID. */
1da177e4
LT
969 isec->sid = sbsec->sid;
970
971 if (sbsec->proc) {
972 struct proc_inode *proci = PROC_I(inode);
973 if (proci->pde) {
974 isec->sclass = inode_mode_to_security_class(inode->i_mode);
975 rc = selinux_proc_get_sid(proci->pde,
976 isec->sclass,
977 &sid);
978 if (rc)
23970741 979 goto out_unlock;
1da177e4
LT
980 isec->sid = sid;
981 }
982 }
983 break;
984 }
985
986 isec->initialized = 1;
987
23970741
EP
988out_unlock:
989 mutex_unlock(&isec->lock);
1da177e4
LT
990out:
991 if (isec->sclass == SECCLASS_FILE)
992 isec->sclass = inode_mode_to_security_class(inode->i_mode);
1da177e4
LT
993 return rc;
994}
995
996/* Convert a Linux signal to an access vector. */
997static inline u32 signal_to_av(int sig)
998{
999 u32 perm = 0;
1000
1001 switch (sig) {
1002 case SIGCHLD:
1003 /* Commonly granted from child to parent. */
1004 perm = PROCESS__SIGCHLD;
1005 break;
1006 case SIGKILL:
1007 /* Cannot be caught or ignored */
1008 perm = PROCESS__SIGKILL;
1009 break;
1010 case SIGSTOP:
1011 /* Cannot be caught or ignored */
1012 perm = PROCESS__SIGSTOP;
1013 break;
1014 default:
1015 /* All other signals. */
1016 perm = PROCESS__SIGNAL;
1017 break;
1018 }
1019
1020 return perm;
1021}
1022
1023/* Check permission betweeen a pair of tasks, e.g. signal checks,
1024 fork check, ptrace check, etc. */
1025static int task_has_perm(struct task_struct *tsk1,
1026 struct task_struct *tsk2,
1027 u32 perms)
1028{
1029 struct task_security_struct *tsec1, *tsec2;
1030
1031 tsec1 = tsk1->security;
1032 tsec2 = tsk2->security;
1033 return avc_has_perm(tsec1->sid, tsec2->sid,
1034 SECCLASS_PROCESS, perms, NULL);
1035}
1036
1037/* Check whether a task is allowed to use a capability. */
1038static int task_has_capability(struct task_struct *tsk,
1039 int cap)
1040{
1041 struct task_security_struct *tsec;
1042 struct avc_audit_data ad;
1043
1044 tsec = tsk->security;
1045
1046 AVC_AUDIT_DATA_INIT(&ad,CAP);
1047 ad.tsk = tsk;
1048 ad.u.cap = cap;
1049
1050 return avc_has_perm(tsec->sid, tsec->sid,
1051 SECCLASS_CAPABILITY, CAP_TO_MASK(cap), &ad);
1052}
1053
1054/* Check whether a task is allowed to use a system operation. */
1055static int task_has_system(struct task_struct *tsk,
1056 u32 perms)
1057{
1058 struct task_security_struct *tsec;
1059
1060 tsec = tsk->security;
1061
1062 return avc_has_perm(tsec->sid, SECINITSID_KERNEL,
1063 SECCLASS_SYSTEM, perms, NULL);
1064}
1065
1066/* Check whether a task has a particular permission to an inode.
1067 The 'adp' parameter is optional and allows other audit
1068 data to be passed (e.g. the dentry). */
1069static int inode_has_perm(struct task_struct *tsk,
1070 struct inode *inode,
1071 u32 perms,
1072 struct avc_audit_data *adp)
1073{
1074 struct task_security_struct *tsec;
1075 struct inode_security_struct *isec;
1076 struct avc_audit_data ad;
1077
1078 tsec = tsk->security;
1079 isec = inode->i_security;
1080
1081 if (!adp) {
1082 adp = &ad;
1083 AVC_AUDIT_DATA_INIT(&ad, FS);
1084 ad.u.fs.inode = inode;
1085 }
1086
1087 return avc_has_perm(tsec->sid, isec->sid, isec->sclass, perms, adp);
1088}
1089
1090/* Same as inode_has_perm, but pass explicit audit data containing
1091 the dentry to help the auditing code to more easily generate the
1092 pathname if needed. */
1093static inline int dentry_has_perm(struct task_struct *tsk,
1094 struct vfsmount *mnt,
1095 struct dentry *dentry,
1096 u32 av)
1097{
1098 struct inode *inode = dentry->d_inode;
1099 struct avc_audit_data ad;
1100 AVC_AUDIT_DATA_INIT(&ad,FS);
1101 ad.u.fs.mnt = mnt;
1102 ad.u.fs.dentry = dentry;
1103 return inode_has_perm(tsk, inode, av, &ad);
1104}
1105
1106/* Check whether a task can use an open file descriptor to
1107 access an inode in a given way. Check access to the
1108 descriptor itself, and then use dentry_has_perm to
1109 check a particular permission to the file.
1110 Access to the descriptor is implicitly granted if it
1111 has the same SID as the process. If av is zero, then
1112 access to the file is not checked, e.g. for cases
1113 where only the descriptor is affected like seek. */
858119e1 1114static int file_has_perm(struct task_struct *tsk,
1da177e4
LT
1115 struct file *file,
1116 u32 av)
1117{
1118 struct task_security_struct *tsec = tsk->security;
1119 struct file_security_struct *fsec = file->f_security;
1120 struct vfsmount *mnt = file->f_vfsmnt;
1121 struct dentry *dentry = file->f_dentry;
1122 struct inode *inode = dentry->d_inode;
1123 struct avc_audit_data ad;
1124 int rc;
1125
1126 AVC_AUDIT_DATA_INIT(&ad, FS);
1127 ad.u.fs.mnt = mnt;
1128 ad.u.fs.dentry = dentry;
1129
1130 if (tsec->sid != fsec->sid) {
1131 rc = avc_has_perm(tsec->sid, fsec->sid,
1132 SECCLASS_FD,
1133 FD__USE,
1134 &ad);
1135 if (rc)
1136 return rc;
1137 }
1138
1139 /* av is zero if only checking access to the descriptor. */
1140 if (av)
1141 return inode_has_perm(tsk, inode, av, &ad);
1142
1143 return 0;
1144}
1145
1146/* Check whether a task can create a file. */
1147static int may_create(struct inode *dir,
1148 struct dentry *dentry,
1149 u16 tclass)
1150{
1151 struct task_security_struct *tsec;
1152 struct inode_security_struct *dsec;
1153 struct superblock_security_struct *sbsec;
1154 u32 newsid;
1155 struct avc_audit_data ad;
1156 int rc;
1157
1158 tsec = current->security;
1159 dsec = dir->i_security;
1160 sbsec = dir->i_sb->s_security;
1161
1162 AVC_AUDIT_DATA_INIT(&ad, FS);
1163 ad.u.fs.dentry = dentry;
1164
1165 rc = avc_has_perm(tsec->sid, dsec->sid, SECCLASS_DIR,
1166 DIR__ADD_NAME | DIR__SEARCH,
1167 &ad);
1168 if (rc)
1169 return rc;
1170
1171 if (tsec->create_sid && sbsec->behavior != SECURITY_FS_USE_MNTPOINT) {
1172 newsid = tsec->create_sid;
1173 } else {
1174 rc = security_transition_sid(tsec->sid, dsec->sid, tclass,
1175 &newsid);
1176 if (rc)
1177 return rc;
1178 }
1179
1180 rc = avc_has_perm(tsec->sid, newsid, tclass, FILE__CREATE, &ad);
1181 if (rc)
1182 return rc;
1183
1184 return avc_has_perm(newsid, sbsec->sid,
1185 SECCLASS_FILESYSTEM,
1186 FILESYSTEM__ASSOCIATE, &ad);
1187}
1188
4eb582cf
ML
1189/* Check whether a task can create a key. */
1190static int may_create_key(u32 ksid,
1191 struct task_struct *ctx)
1192{
1193 struct task_security_struct *tsec;
1194
1195 tsec = ctx->security;
1196
1197 return avc_has_perm(tsec->sid, ksid, SECCLASS_KEY, KEY__CREATE, NULL);
1198}
1199
1da177e4
LT
1200#define MAY_LINK 0
1201#define MAY_UNLINK 1
1202#define MAY_RMDIR 2
1203
1204/* Check whether a task can link, unlink, or rmdir a file/directory. */
1205static int may_link(struct inode *dir,
1206 struct dentry *dentry,
1207 int kind)
1208
1209{
1210 struct task_security_struct *tsec;
1211 struct inode_security_struct *dsec, *isec;
1212 struct avc_audit_data ad;
1213 u32 av;
1214 int rc;
1215
1216 tsec = current->security;
1217 dsec = dir->i_security;
1218 isec = dentry->d_inode->i_security;
1219
1220 AVC_AUDIT_DATA_INIT(&ad, FS);
1221 ad.u.fs.dentry = dentry;
1222
1223 av = DIR__SEARCH;
1224 av |= (kind ? DIR__REMOVE_NAME : DIR__ADD_NAME);
1225 rc = avc_has_perm(tsec->sid, dsec->sid, SECCLASS_DIR, av, &ad);
1226 if (rc)
1227 return rc;
1228
1229 switch (kind) {
1230 case MAY_LINK:
1231 av = FILE__LINK;
1232 break;
1233 case MAY_UNLINK:
1234 av = FILE__UNLINK;
1235 break;
1236 case MAY_RMDIR:
1237 av = DIR__RMDIR;
1238 break;
1239 default:
1240 printk(KERN_WARNING "may_link: unrecognized kind %d\n", kind);
1241 return 0;
1242 }
1243
1244 rc = avc_has_perm(tsec->sid, isec->sid, isec->sclass, av, &ad);
1245 return rc;
1246}
1247
1248static inline int may_rename(struct inode *old_dir,
1249 struct dentry *old_dentry,
1250 struct inode *new_dir,
1251 struct dentry *new_dentry)
1252{
1253 struct task_security_struct *tsec;
1254 struct inode_security_struct *old_dsec, *new_dsec, *old_isec, *new_isec;
1255 struct avc_audit_data ad;
1256 u32 av;
1257 int old_is_dir, new_is_dir;
1258 int rc;
1259
1260 tsec = current->security;
1261 old_dsec = old_dir->i_security;
1262 old_isec = old_dentry->d_inode->i_security;
1263 old_is_dir = S_ISDIR(old_dentry->d_inode->i_mode);
1264 new_dsec = new_dir->i_security;
1265
1266 AVC_AUDIT_DATA_INIT(&ad, FS);
1267
1268 ad.u.fs.dentry = old_dentry;
1269 rc = avc_has_perm(tsec->sid, old_dsec->sid, SECCLASS_DIR,
1270 DIR__REMOVE_NAME | DIR__SEARCH, &ad);
1271 if (rc)
1272 return rc;
1273 rc = avc_has_perm(tsec->sid, old_isec->sid,
1274 old_isec->sclass, FILE__RENAME, &ad);
1275 if (rc)
1276 return rc;
1277 if (old_is_dir && new_dir != old_dir) {
1278 rc = avc_has_perm(tsec->sid, old_isec->sid,
1279 old_isec->sclass, DIR__REPARENT, &ad);
1280 if (rc)
1281 return rc;
1282 }
1283
1284 ad.u.fs.dentry = new_dentry;
1285 av = DIR__ADD_NAME | DIR__SEARCH;
1286 if (new_dentry->d_inode)
1287 av |= DIR__REMOVE_NAME;
1288 rc = avc_has_perm(tsec->sid, new_dsec->sid, SECCLASS_DIR, av, &ad);
1289 if (rc)
1290 return rc;
1291 if (new_dentry->d_inode) {
1292 new_isec = new_dentry->d_inode->i_security;
1293 new_is_dir = S_ISDIR(new_dentry->d_inode->i_mode);
1294 rc = avc_has_perm(tsec->sid, new_isec->sid,
1295 new_isec->sclass,
1296 (new_is_dir ? DIR__RMDIR : FILE__UNLINK), &ad);
1297 if (rc)
1298 return rc;
1299 }
1300
1301 return 0;
1302}
1303
1304/* Check whether a task can perform a filesystem operation. */
1305static int superblock_has_perm(struct task_struct *tsk,
1306 struct super_block *sb,
1307 u32 perms,
1308 struct avc_audit_data *ad)
1309{
1310 struct task_security_struct *tsec;
1311 struct superblock_security_struct *sbsec;
1312
1313 tsec = tsk->security;
1314 sbsec = sb->s_security;
1315 return avc_has_perm(tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM,
1316 perms, ad);
1317}
1318
1319/* Convert a Linux mode and permission mask to an access vector. */
1320static inline u32 file_mask_to_av(int mode, int mask)
1321{
1322 u32 av = 0;
1323
1324 if ((mode & S_IFMT) != S_IFDIR) {
1325 if (mask & MAY_EXEC)
1326 av |= FILE__EXECUTE;
1327 if (mask & MAY_READ)
1328 av |= FILE__READ;
1329
1330 if (mask & MAY_APPEND)
1331 av |= FILE__APPEND;
1332 else if (mask & MAY_WRITE)
1333 av |= FILE__WRITE;
1334
1335 } else {
1336 if (mask & MAY_EXEC)
1337 av |= DIR__SEARCH;
1338 if (mask & MAY_WRITE)
1339 av |= DIR__WRITE;
1340 if (mask & MAY_READ)
1341 av |= DIR__READ;
1342 }
1343
1344 return av;
1345}
1346
1347/* Convert a Linux file to an access vector. */
1348static inline u32 file_to_av(struct file *file)
1349{
1350 u32 av = 0;
1351
1352 if (file->f_mode & FMODE_READ)
1353 av |= FILE__READ;
1354 if (file->f_mode & FMODE_WRITE) {
1355 if (file->f_flags & O_APPEND)
1356 av |= FILE__APPEND;
1357 else
1358 av |= FILE__WRITE;
1359 }
1360
1361 return av;
1362}
1363
1da177e4
LT
1364/* Hook functions begin here. */
1365
1366static int selinux_ptrace(struct task_struct *parent, struct task_struct *child)
1367{
1368 struct task_security_struct *psec = parent->security;
1369 struct task_security_struct *csec = child->security;
1370 int rc;
1371
1372 rc = secondary_ops->ptrace(parent,child);
1373 if (rc)
1374 return rc;
1375
1376 rc = task_has_perm(parent, child, PROCESS__PTRACE);
1377 /* Save the SID of the tracing process for later use in apply_creds. */
341c2d80 1378 if (!(child->ptrace & PT_PTRACED) && !rc)
1da177e4
LT
1379 csec->ptrace_sid = psec->sid;
1380 return rc;
1381}
1382
1383static int selinux_capget(struct task_struct *target, kernel_cap_t *effective,
1384 kernel_cap_t *inheritable, kernel_cap_t *permitted)
1385{
1386 int error;
1387
1388 error = task_has_perm(current, target, PROCESS__GETCAP);
1389 if (error)
1390 return error;
1391
1392 return secondary_ops->capget(target, effective, inheritable, permitted);
1393}
1394
1395static int selinux_capset_check(struct task_struct *target, kernel_cap_t *effective,
1396 kernel_cap_t *inheritable, kernel_cap_t *permitted)
1397{
1398 int error;
1399
1400 error = secondary_ops->capset_check(target, effective, inheritable, permitted);
1401 if (error)
1402 return error;
1403
1404 return task_has_perm(current, target, PROCESS__SETCAP);
1405}
1406
1407static void selinux_capset_set(struct task_struct *target, kernel_cap_t *effective,
1408 kernel_cap_t *inheritable, kernel_cap_t *permitted)
1409{
1410 secondary_ops->capset_set(target, effective, inheritable, permitted);
1411}
1412
1413static int selinux_capable(struct task_struct *tsk, int cap)
1414{
1415 int rc;
1416
1417 rc = secondary_ops->capable(tsk, cap);
1418 if (rc)
1419 return rc;
1420
1421 return task_has_capability(tsk,cap);
1422}
1423
1424static int selinux_sysctl(ctl_table *table, int op)
1425{
1426 int error = 0;
1427 u32 av;
1428 struct task_security_struct *tsec;
1429 u32 tsid;
1430 int rc;
1431
1432 rc = secondary_ops->sysctl(table, op);
1433 if (rc)
1434 return rc;
1435
1436 tsec = current->security;
1437
1438 rc = selinux_proc_get_sid(table->de, (op == 001) ?
1439 SECCLASS_DIR : SECCLASS_FILE, &tsid);
1440 if (rc) {
1441 /* Default to the well-defined sysctl SID. */
1442 tsid = SECINITSID_SYSCTL;
1443 }
1444
1445 /* The op values are "defined" in sysctl.c, thereby creating
1446 * a bad coupling between this module and sysctl.c */
1447 if(op == 001) {
1448 error = avc_has_perm(tsec->sid, tsid,
1449 SECCLASS_DIR, DIR__SEARCH, NULL);
1450 } else {
1451 av = 0;
1452 if (op & 004)
1453 av |= FILE__READ;
1454 if (op & 002)
1455 av |= FILE__WRITE;
1456 if (av)
1457 error = avc_has_perm(tsec->sid, tsid,
1458 SECCLASS_FILE, av, NULL);
1459 }
1460
1461 return error;
1462}
1463
1464static int selinux_quotactl(int cmds, int type, int id, struct super_block *sb)
1465{
1466 int rc = 0;
1467
1468 if (!sb)
1469 return 0;
1470
1471 switch (cmds) {
1472 case Q_SYNC:
1473 case Q_QUOTAON:
1474 case Q_QUOTAOFF:
1475 case Q_SETINFO:
1476 case Q_SETQUOTA:
1477 rc = superblock_has_perm(current,
1478 sb,
1479 FILESYSTEM__QUOTAMOD, NULL);
1480 break;
1481 case Q_GETFMT:
1482 case Q_GETINFO:
1483 case Q_GETQUOTA:
1484 rc = superblock_has_perm(current,
1485 sb,
1486 FILESYSTEM__QUOTAGET, NULL);
1487 break;
1488 default:
1489 rc = 0; /* let the kernel handle invalid cmds */
1490 break;
1491 }
1492 return rc;
1493}
1494
1495static int selinux_quota_on(struct dentry *dentry)
1496{
1497 return dentry_has_perm(current, NULL, dentry, FILE__QUOTAON);
1498}
1499
1500static int selinux_syslog(int type)
1501{
1502 int rc;
1503
1504 rc = secondary_ops->syslog(type);
1505 if (rc)
1506 return rc;
1507
1508 switch (type) {
1509 case 3: /* Read last kernel messages */
1510 case 10: /* Return size of the log buffer */
1511 rc = task_has_system(current, SYSTEM__SYSLOG_READ);
1512 break;
1513 case 6: /* Disable logging to console */
1514 case 7: /* Enable logging to console */
1515 case 8: /* Set level of messages printed to console */
1516 rc = task_has_system(current, SYSTEM__SYSLOG_CONSOLE);
1517 break;
1518 case 0: /* Close log */
1519 case 1: /* Open log */
1520 case 2: /* Read from log */
1521 case 4: /* Read/clear last kernel messages */
1522 case 5: /* Clear ring buffer */
1523 default:
1524 rc = task_has_system(current, SYSTEM__SYSLOG_MOD);
1525 break;
1526 }
1527 return rc;
1528}
1529
1530/*
1531 * Check that a process has enough memory to allocate a new virtual
1532 * mapping. 0 means there is enough memory for the allocation to
1533 * succeed and -ENOMEM implies there is not.
1534 *
1535 * Note that secondary_ops->capable and task_has_perm_noaudit return 0
1536 * if the capability is granted, but __vm_enough_memory requires 1 if
1537 * the capability is granted.
1538 *
1539 * Do not audit the selinux permission check, as this is applied to all
1540 * processes that allocate mappings.
1541 */
1542static int selinux_vm_enough_memory(long pages)
1543{
1544 int rc, cap_sys_admin = 0;
1545 struct task_security_struct *tsec = current->security;
1546
1547 rc = secondary_ops->capable(current, CAP_SYS_ADMIN);
1548 if (rc == 0)
1549 rc = avc_has_perm_noaudit(tsec->sid, tsec->sid,
1550 SECCLASS_CAPABILITY,
1551 CAP_TO_MASK(CAP_SYS_ADMIN),
1552 NULL);
1553
1554 if (rc == 0)
1555 cap_sys_admin = 1;
1556
1557 return __vm_enough_memory(pages, cap_sys_admin);
1558}
1559
1560/* binprm security operations */
1561
1562static int selinux_bprm_alloc_security(struct linux_binprm *bprm)
1563{
1564 struct bprm_security_struct *bsec;
1565
89d155ef 1566 bsec = kzalloc(sizeof(struct bprm_security_struct), GFP_KERNEL);
1da177e4
LT
1567 if (!bsec)
1568 return -ENOMEM;
1569
1da177e4
LT
1570 bsec->bprm = bprm;
1571 bsec->sid = SECINITSID_UNLABELED;
1572 bsec->set = 0;
1573
1574 bprm->security = bsec;
1575 return 0;
1576}
1577
1578static int selinux_bprm_set_security(struct linux_binprm *bprm)
1579{
1580 struct task_security_struct *tsec;
1581 struct inode *inode = bprm->file->f_dentry->d_inode;
1582 struct inode_security_struct *isec;
1583 struct bprm_security_struct *bsec;
1584 u32 newsid;
1585 struct avc_audit_data ad;
1586 int rc;
1587
1588 rc = secondary_ops->bprm_set_security(bprm);
1589 if (rc)
1590 return rc;
1591
1592 bsec = bprm->security;
1593
1594 if (bsec->set)
1595 return 0;
1596
1597 tsec = current->security;
1598 isec = inode->i_security;
1599
1600 /* Default to the current task SID. */
1601 bsec->sid = tsec->sid;
1602
28eba5bf 1603 /* Reset fs, key, and sock SIDs on execve. */
1da177e4 1604 tsec->create_sid = 0;
28eba5bf 1605 tsec->keycreate_sid = 0;
42c3e03e 1606 tsec->sockcreate_sid = 0;
1da177e4
LT
1607
1608 if (tsec->exec_sid) {
1609 newsid = tsec->exec_sid;
1610 /* Reset exec SID on execve. */
1611 tsec->exec_sid = 0;
1612 } else {
1613 /* Check for a default transition on this program. */
1614 rc = security_transition_sid(tsec->sid, isec->sid,
1615 SECCLASS_PROCESS, &newsid);
1616 if (rc)
1617 return rc;
1618 }
1619
1620 AVC_AUDIT_DATA_INIT(&ad, FS);
1621 ad.u.fs.mnt = bprm->file->f_vfsmnt;
1622 ad.u.fs.dentry = bprm->file->f_dentry;
1623
1624 if (bprm->file->f_vfsmnt->mnt_flags & MNT_NOSUID)
1625 newsid = tsec->sid;
1626
1627 if (tsec->sid == newsid) {
1628 rc = avc_has_perm(tsec->sid, isec->sid,
1629 SECCLASS_FILE, FILE__EXECUTE_NO_TRANS, &ad);
1630 if (rc)
1631 return rc;
1632 } else {
1633 /* Check permissions for the transition. */
1634 rc = avc_has_perm(tsec->sid, newsid,
1635 SECCLASS_PROCESS, PROCESS__TRANSITION, &ad);
1636 if (rc)
1637 return rc;
1638
1639 rc = avc_has_perm(newsid, isec->sid,
1640 SECCLASS_FILE, FILE__ENTRYPOINT, &ad);
1641 if (rc)
1642 return rc;
1643
1644 /* Clear any possibly unsafe personality bits on exec: */
1645 current->personality &= ~PER_CLEAR_ON_SETID;
1646
1647 /* Set the security field to the new SID. */
1648 bsec->sid = newsid;
1649 }
1650
1651 bsec->set = 1;
1652 return 0;
1653}
1654
1655static int selinux_bprm_check_security (struct linux_binprm *bprm)
1656{
1657 return secondary_ops->bprm_check_security(bprm);
1658}
1659
1660
1661static int selinux_bprm_secureexec (struct linux_binprm *bprm)
1662{
1663 struct task_security_struct *tsec = current->security;
1664 int atsecure = 0;
1665
1666 if (tsec->osid != tsec->sid) {
1667 /* Enable secure mode for SIDs transitions unless
1668 the noatsecure permission is granted between
1669 the two SIDs, i.e. ahp returns 0. */
1670 atsecure = avc_has_perm(tsec->osid, tsec->sid,
1671 SECCLASS_PROCESS,
1672 PROCESS__NOATSECURE, NULL);
1673 }
1674
1675 return (atsecure || secondary_ops->bprm_secureexec(bprm));
1676}
1677
1678static void selinux_bprm_free_security(struct linux_binprm *bprm)
1679{
9a5f04bf 1680 kfree(bprm->security);
1da177e4 1681 bprm->security = NULL;
1da177e4
LT
1682}
1683
1684extern struct vfsmount *selinuxfs_mount;
1685extern struct dentry *selinux_null;
1686
1687/* Derived from fs/exec.c:flush_old_files. */
1688static inline void flush_unauthorized_files(struct files_struct * files)
1689{
1690 struct avc_audit_data ad;
1691 struct file *file, *devnull = NULL;
b20c8122 1692 struct tty_struct *tty;
badf1662 1693 struct fdtable *fdt;
1da177e4
LT
1694 long j = -1;
1695
b20c8122
SS
1696 mutex_lock(&tty_mutex);
1697 tty = current->signal->tty;
1da177e4
LT
1698 if (tty) {
1699 file_list_lock();
2f512016 1700 file = list_entry(tty->tty_files.next, typeof(*file), f_u.fu_list);
1da177e4
LT
1701 if (file) {
1702 /* Revalidate access to controlling tty.
1703 Use inode_has_perm on the tty inode directly rather
1704 than using file_has_perm, as this particular open
1705 file may belong to another process and we are only
1706 interested in the inode-based check here. */
1707 struct inode *inode = file->f_dentry->d_inode;
1708 if (inode_has_perm(current, inode,
1709 FILE__READ | FILE__WRITE, NULL)) {
1710 /* Reset controlling tty. */
1711 current->signal->tty = NULL;
1712 current->signal->tty_old_pgrp = 0;
1713 }
1714 }
1715 file_list_unlock();
1716 }
b20c8122 1717 mutex_unlock(&tty_mutex);
1da177e4
LT
1718
1719 /* Revalidate access to inherited open files. */
1720
1721 AVC_AUDIT_DATA_INIT(&ad,FS);
1722
1723 spin_lock(&files->file_lock);
1724 for (;;) {
1725 unsigned long set, i;
1726 int fd;
1727
1728 j++;
1729 i = j * __NFDBITS;
badf1662
DS
1730 fdt = files_fdtable(files);
1731 if (i >= fdt->max_fds || i >= fdt->max_fdset)
1da177e4 1732 break;
badf1662 1733 set = fdt->open_fds->fds_bits[j];
1da177e4
LT
1734 if (!set)
1735 continue;
1736 spin_unlock(&files->file_lock);
1737 for ( ; set ; i++,set >>= 1) {
1738 if (set & 1) {
1739 file = fget(i);
1740 if (!file)
1741 continue;
1742 if (file_has_perm(current,
1743 file,
1744 file_to_av(file))) {
1745 sys_close(i);
1746 fd = get_unused_fd();
1747 if (fd != i) {
1748 if (fd >= 0)
1749 put_unused_fd(fd);
1750 fput(file);
1751 continue;
1752 }
1753 if (devnull) {
095975da 1754 get_file(devnull);
1da177e4
LT
1755 } else {
1756 devnull = dentry_open(dget(selinux_null), mntget(selinuxfs_mount), O_RDWR);
1757 if (!devnull) {
1758 put_unused_fd(fd);
1759 fput(file);
1760 continue;
1761 }
1762 }
1763 fd_install(fd, devnull);
1764 }
1765 fput(file);
1766 }
1767 }
1768 spin_lock(&files->file_lock);
1769
1770 }
1771 spin_unlock(&files->file_lock);
1772}
1773
1774static void selinux_bprm_apply_creds(struct linux_binprm *bprm, int unsafe)
1775{
1776 struct task_security_struct *tsec;
1777 struct bprm_security_struct *bsec;
1778 u32 sid;
1779 int rc;
1780
1781 secondary_ops->bprm_apply_creds(bprm, unsafe);
1782
1783 tsec = current->security;
1784
1785 bsec = bprm->security;
1786 sid = bsec->sid;
1787
1788 tsec->osid = tsec->sid;
1789 bsec->unsafe = 0;
1790 if (tsec->sid != sid) {
1791 /* Check for shared state. If not ok, leave SID
1792 unchanged and kill. */
1793 if (unsafe & LSM_UNSAFE_SHARE) {
1794 rc = avc_has_perm(tsec->sid, sid, SECCLASS_PROCESS,
1795 PROCESS__SHARE, NULL);
1796 if (rc) {
1797 bsec->unsafe = 1;
1798 return;
1799 }
1800 }
1801
1802 /* Check for ptracing, and update the task SID if ok.
1803 Otherwise, leave SID unchanged and kill. */
1804 if (unsafe & (LSM_UNSAFE_PTRACE | LSM_UNSAFE_PTRACE_CAP)) {
1805 rc = avc_has_perm(tsec->ptrace_sid, sid,
1806 SECCLASS_PROCESS, PROCESS__PTRACE,
1807 NULL);
1808 if (rc) {
1809 bsec->unsafe = 1;
1810 return;
1811 }
1812 }
1813 tsec->sid = sid;
1814 }
1815}
1816
1817/*
1818 * called after apply_creds without the task lock held
1819 */
1820static void selinux_bprm_post_apply_creds(struct linux_binprm *bprm)
1821{
1822 struct task_security_struct *tsec;
1823 struct rlimit *rlim, *initrlim;
1824 struct itimerval itimer;
1825 struct bprm_security_struct *bsec;
1826 int rc, i;
1827
1828 tsec = current->security;
1829 bsec = bprm->security;
1830
1831 if (bsec->unsafe) {
1832 force_sig_specific(SIGKILL, current);
1833 return;
1834 }
1835 if (tsec->osid == tsec->sid)
1836 return;
1837
1838 /* Close files for which the new task SID is not authorized. */
1839 flush_unauthorized_files(current->files);
1840
1841 /* Check whether the new SID can inherit signal state
1842 from the old SID. If not, clear itimers to avoid
1843 subsequent signal generation and flush and unblock
1844 signals. This must occur _after_ the task SID has
1845 been updated so that any kill done after the flush
1846 will be checked against the new SID. */
1847 rc = avc_has_perm(tsec->osid, tsec->sid, SECCLASS_PROCESS,
1848 PROCESS__SIGINH, NULL);
1849 if (rc) {
1850 memset(&itimer, 0, sizeof itimer);
1851 for (i = 0; i < 3; i++)
1852 do_setitimer(i, &itimer, NULL);
1853 flush_signals(current);
1854 spin_lock_irq(&current->sighand->siglock);
1855 flush_signal_handlers(current, 1);
1856 sigemptyset(&current->blocked);
1857 recalc_sigpending();
1858 spin_unlock_irq(&current->sighand->siglock);
1859 }
1860
1861 /* Check whether the new SID can inherit resource limits
1862 from the old SID. If not, reset all soft limits to
1863 the lower of the current task's hard limit and the init
1864 task's soft limit. Note that the setting of hard limits
1865 (even to lower them) can be controlled by the setrlimit
1866 check. The inclusion of the init task's soft limit into
1867 the computation is to avoid resetting soft limits higher
1868 than the default soft limit for cases where the default
1869 is lower than the hard limit, e.g. RLIMIT_CORE or
1870 RLIMIT_STACK.*/
1871 rc = avc_has_perm(tsec->osid, tsec->sid, SECCLASS_PROCESS,
1872 PROCESS__RLIMITINH, NULL);
1873 if (rc) {
1874 for (i = 0; i < RLIM_NLIMITS; i++) {
1875 rlim = current->signal->rlim + i;
1876 initrlim = init_task.signal->rlim+i;
1877 rlim->rlim_cur = min(rlim->rlim_max,initrlim->rlim_cur);
1878 }
1879 if (current->signal->rlim[RLIMIT_CPU].rlim_cur != RLIM_INFINITY) {
1880 /*
1881 * This will cause RLIMIT_CPU calculations
1882 * to be refigured.
1883 */
1884 current->it_prof_expires = jiffies_to_cputime(1);
1885 }
1886 }
1887
1888 /* Wake up the parent if it is waiting so that it can
1889 recheck wait permission to the new task SID. */
1890 wake_up_interruptible(&current->parent->signal->wait_chldexit);
1891}
1892
1893/* superblock security operations */
1894
1895static int selinux_sb_alloc_security(struct super_block *sb)
1896{
1897 return superblock_alloc_security(sb);
1898}
1899
1900static void selinux_sb_free_security(struct super_block *sb)
1901{
1902 superblock_free_security(sb);
1903}
1904
1905static inline int match_prefix(char *prefix, int plen, char *option, int olen)
1906{
1907 if (plen > olen)
1908 return 0;
1909
1910 return !memcmp(prefix, option, plen);
1911}
1912
1913static inline int selinux_option(char *option, int len)
1914{
1915 return (match_prefix("context=", sizeof("context=")-1, option, len) ||
1916 match_prefix("fscontext=", sizeof("fscontext=")-1, option, len) ||
0808925e
EP
1917 match_prefix("defcontext=", sizeof("defcontext=")-1, option, len) ||
1918 match_prefix("rootcontext=", sizeof("rootcontext=")-1, option, len));
1da177e4
LT
1919}
1920
1921static inline void take_option(char **to, char *from, int *first, int len)
1922{
1923 if (!*first) {
1924 **to = ',';
1925 *to += 1;
3528a953 1926 } else
1da177e4
LT
1927 *first = 0;
1928 memcpy(*to, from, len);
1929 *to += len;
1930}
1931
3528a953
CO
1932static inline void take_selinux_option(char **to, char *from, int *first,
1933 int len)
1934{
1935 int current_size = 0;
1936
1937 if (!*first) {
1938 **to = '|';
1939 *to += 1;
1940 }
1941 else
1942 *first = 0;
1943
1944 while (current_size < len) {
1945 if (*from != '"') {
1946 **to = *from;
1947 *to += 1;
1948 }
1949 from += 1;
1950 current_size += 1;
1951 }
1952}
1953
1da177e4
LT
1954static int selinux_sb_copy_data(struct file_system_type *type, void *orig, void *copy)
1955{
1956 int fnosec, fsec, rc = 0;
1957 char *in_save, *in_curr, *in_end;
1958 char *sec_curr, *nosec_save, *nosec;
3528a953 1959 int open_quote = 0;
1da177e4
LT
1960
1961 in_curr = orig;
1962 sec_curr = copy;
1963
1964 /* Binary mount data: just copy */
1965 if (type->fs_flags & FS_BINARY_MOUNTDATA) {
1966 copy_page(sec_curr, in_curr);
1967 goto out;
1968 }
1969
1970 nosec = (char *)get_zeroed_page(GFP_KERNEL);
1971 if (!nosec) {
1972 rc = -ENOMEM;
1973 goto out;
1974 }
1975
1976 nosec_save = nosec;
1977 fnosec = fsec = 1;
1978 in_save = in_end = orig;
1979
1980 do {
3528a953
CO
1981 if (*in_end == '"')
1982 open_quote = !open_quote;
1983 if ((*in_end == ',' && open_quote == 0) ||
1984 *in_end == '\0') {
1da177e4
LT
1985 int len = in_end - in_curr;
1986
1987 if (selinux_option(in_curr, len))
3528a953 1988 take_selinux_option(&sec_curr, in_curr, &fsec, len);
1da177e4
LT
1989 else
1990 take_option(&nosec, in_curr, &fnosec, len);
1991
1992 in_curr = in_end + 1;
1993 }
1994 } while (*in_end++);
1995
6931dfc9 1996 strcpy(in_save, nosec_save);
da3caa20 1997 free_page((unsigned long)nosec_save);
1da177e4
LT
1998out:
1999 return rc;
2000}
2001
2002static int selinux_sb_kern_mount(struct super_block *sb, void *data)
2003{
2004 struct avc_audit_data ad;
2005 int rc;
2006
2007 rc = superblock_doinit(sb, data);
2008 if (rc)
2009 return rc;
2010
2011 AVC_AUDIT_DATA_INIT(&ad,FS);
2012 ad.u.fs.dentry = sb->s_root;
2013 return superblock_has_perm(current, sb, FILESYSTEM__MOUNT, &ad);
2014}
2015
726c3342 2016static int selinux_sb_statfs(struct dentry *dentry)
1da177e4
LT
2017{
2018 struct avc_audit_data ad;
2019
2020 AVC_AUDIT_DATA_INIT(&ad,FS);
726c3342
DH
2021 ad.u.fs.dentry = dentry->d_sb->s_root;
2022 return superblock_has_perm(current, dentry->d_sb, FILESYSTEM__GETATTR, &ad);
1da177e4
LT
2023}
2024
2025static int selinux_mount(char * dev_name,
2026 struct nameidata *nd,
2027 char * type,
2028 unsigned long flags,
2029 void * data)
2030{
2031 int rc;
2032
2033 rc = secondary_ops->sb_mount(dev_name, nd, type, flags, data);
2034 if (rc)
2035 return rc;
2036
2037 if (flags & MS_REMOUNT)
2038 return superblock_has_perm(current, nd->mnt->mnt_sb,
2039 FILESYSTEM__REMOUNT, NULL);
2040 else
2041 return dentry_has_perm(current, nd->mnt, nd->dentry,
2042 FILE__MOUNTON);
2043}
2044
2045static int selinux_umount(struct vfsmount *mnt, int flags)
2046{
2047 int rc;
2048
2049 rc = secondary_ops->sb_umount(mnt, flags);
2050 if (rc)
2051 return rc;
2052
2053 return superblock_has_perm(current,mnt->mnt_sb,
2054 FILESYSTEM__UNMOUNT,NULL);
2055}
2056
2057/* inode security operations */
2058
2059static int selinux_inode_alloc_security(struct inode *inode)
2060{
2061 return inode_alloc_security(inode);
2062}
2063
2064static void selinux_inode_free_security(struct inode *inode)
2065{
2066 inode_free_security(inode);
2067}
2068
5e41ff9e
SS
2069static int selinux_inode_init_security(struct inode *inode, struct inode *dir,
2070 char **name, void **value,
2071 size_t *len)
2072{
2073 struct task_security_struct *tsec;
2074 struct inode_security_struct *dsec;
2075 struct superblock_security_struct *sbsec;
570bc1c2 2076 u32 newsid, clen;
5e41ff9e 2077 int rc;
570bc1c2 2078 char *namep = NULL, *context;
5e41ff9e
SS
2079
2080 tsec = current->security;
2081 dsec = dir->i_security;
2082 sbsec = dir->i_sb->s_security;
5e41ff9e
SS
2083
2084 if (tsec->create_sid && sbsec->behavior != SECURITY_FS_USE_MNTPOINT) {
2085 newsid = tsec->create_sid;
2086 } else {
2087 rc = security_transition_sid(tsec->sid, dsec->sid,
2088 inode_mode_to_security_class(inode->i_mode),
2089 &newsid);
2090 if (rc) {
2091 printk(KERN_WARNING "%s: "
2092 "security_transition_sid failed, rc=%d (dev=%s "
2093 "ino=%ld)\n",
2094 __FUNCTION__,
2095 -rc, inode->i_sb->s_id, inode->i_ino);
2096 return rc;
2097 }
2098 }
2099
296fddf7
EP
2100 /* Possibly defer initialization to selinux_complete_init. */
2101 if (sbsec->initialized) {
2102 struct inode_security_struct *isec = inode->i_security;
2103 isec->sclass = inode_mode_to_security_class(inode->i_mode);
2104 isec->sid = newsid;
2105 isec->initialized = 1;
2106 }
5e41ff9e 2107
8aad3875 2108 if (!ss_initialized || sbsec->behavior == SECURITY_FS_USE_MNTPOINT)
25a74f3b
SS
2109 return -EOPNOTSUPP;
2110
570bc1c2
SS
2111 if (name) {
2112 namep = kstrdup(XATTR_SELINUX_SUFFIX, GFP_KERNEL);
2113 if (!namep)
2114 return -ENOMEM;
2115 *name = namep;
2116 }
5e41ff9e 2117
570bc1c2
SS
2118 if (value && len) {
2119 rc = security_sid_to_context(newsid, &context, &clen);
2120 if (rc) {
2121 kfree(namep);
2122 return rc;
2123 }
2124 *value = context;
2125 *len = clen;
5e41ff9e 2126 }
5e41ff9e 2127
5e41ff9e
SS
2128 return 0;
2129}
2130
1da177e4
LT
2131static int selinux_inode_create(struct inode *dir, struct dentry *dentry, int mask)
2132{
2133 return may_create(dir, dentry, SECCLASS_FILE);
2134}
2135
1da177e4
LT
2136static int selinux_inode_link(struct dentry *old_dentry, struct inode *dir, struct dentry *new_dentry)
2137{
2138 int rc;
2139
2140 rc = secondary_ops->inode_link(old_dentry,dir,new_dentry);
2141 if (rc)
2142 return rc;
2143 return may_link(dir, old_dentry, MAY_LINK);
2144}
2145
1da177e4
LT
2146static int selinux_inode_unlink(struct inode *dir, struct dentry *dentry)
2147{
2148 int rc;
2149
2150 rc = secondary_ops->inode_unlink(dir, dentry);
2151 if (rc)
2152 return rc;
2153 return may_link(dir, dentry, MAY_UNLINK);
2154}
2155
2156static int selinux_inode_symlink(struct inode *dir, struct dentry *dentry, const char *name)
2157{
2158 return may_create(dir, dentry, SECCLASS_LNK_FILE);
2159}
2160
1da177e4
LT
2161static int selinux_inode_mkdir(struct inode *dir, struct dentry *dentry, int mask)
2162{
2163 return may_create(dir, dentry, SECCLASS_DIR);
2164}
2165
1da177e4
LT
2166static int selinux_inode_rmdir(struct inode *dir, struct dentry *dentry)
2167{
2168 return may_link(dir, dentry, MAY_RMDIR);
2169}
2170
2171static int selinux_inode_mknod(struct inode *dir, struct dentry *dentry, int mode, dev_t dev)
2172{
2173 int rc;
2174
2175 rc = secondary_ops->inode_mknod(dir, dentry, mode, dev);
2176 if (rc)
2177 return rc;
2178
2179 return may_create(dir, dentry, inode_mode_to_security_class(mode));
2180}
2181
1da177e4
LT
2182static int selinux_inode_rename(struct inode *old_inode, struct dentry *old_dentry,
2183 struct inode *new_inode, struct dentry *new_dentry)
2184{
2185 return may_rename(old_inode, old_dentry, new_inode, new_dentry);
2186}
2187
1da177e4
LT
2188static int selinux_inode_readlink(struct dentry *dentry)
2189{
2190 return dentry_has_perm(current, NULL, dentry, FILE__READ);
2191}
2192
2193static int selinux_inode_follow_link(struct dentry *dentry, struct nameidata *nameidata)
2194{
2195 int rc;
2196
2197 rc = secondary_ops->inode_follow_link(dentry,nameidata);
2198 if (rc)
2199 return rc;
2200 return dentry_has_perm(current, NULL, dentry, FILE__READ);
2201}
2202
2203static int selinux_inode_permission(struct inode *inode, int mask,
2204 struct nameidata *nd)
2205{
2206 int rc;
2207
2208 rc = secondary_ops->inode_permission(inode, mask, nd);
2209 if (rc)
2210 return rc;
2211
2212 if (!mask) {
2213 /* No permission to check. Existence test. */
2214 return 0;
2215 }
2216
2217 return inode_has_perm(current, inode,
2218 file_mask_to_av(inode->i_mode, mask), NULL);
2219}
2220
2221static int selinux_inode_setattr(struct dentry *dentry, struct iattr *iattr)
2222{
2223 int rc;
2224
2225 rc = secondary_ops->inode_setattr(dentry, iattr);
2226 if (rc)
2227 return rc;
2228
2229 if (iattr->ia_valid & ATTR_FORCE)
2230 return 0;
2231
2232 if (iattr->ia_valid & (ATTR_MODE | ATTR_UID | ATTR_GID |
2233 ATTR_ATIME_SET | ATTR_MTIME_SET))
2234 return dentry_has_perm(current, NULL, dentry, FILE__SETATTR);
2235
2236 return dentry_has_perm(current, NULL, dentry, FILE__WRITE);
2237}
2238
2239static int selinux_inode_getattr(struct vfsmount *mnt, struct dentry *dentry)
2240{
2241 return dentry_has_perm(current, mnt, dentry, FILE__GETATTR);
2242}
2243
2244static int selinux_inode_setxattr(struct dentry *dentry, char *name, void *value, size_t size, int flags)
2245{
2246 struct task_security_struct *tsec = current->security;
2247 struct inode *inode = dentry->d_inode;
2248 struct inode_security_struct *isec = inode->i_security;
2249 struct superblock_security_struct *sbsec;
2250 struct avc_audit_data ad;
2251 u32 newsid;
2252 int rc = 0;
2253
2254 if (strcmp(name, XATTR_NAME_SELINUX)) {
2255 if (!strncmp(name, XATTR_SECURITY_PREFIX,
2256 sizeof XATTR_SECURITY_PREFIX - 1) &&
2257 !capable(CAP_SYS_ADMIN)) {
2258 /* A different attribute in the security namespace.
2259 Restrict to administrator. */
2260 return -EPERM;
2261 }
2262
2263 /* Not an attribute we recognize, so just check the
2264 ordinary setattr permission. */
2265 return dentry_has_perm(current, NULL, dentry, FILE__SETATTR);
2266 }
2267
2268 sbsec = inode->i_sb->s_security;
2269 if (sbsec->behavior == SECURITY_FS_USE_MNTPOINT)
2270 return -EOPNOTSUPP;
2271
2272 if ((current->fsuid != inode->i_uid) && !capable(CAP_FOWNER))
2273 return -EPERM;
2274
2275 AVC_AUDIT_DATA_INIT(&ad,FS);
2276 ad.u.fs.dentry = dentry;
2277
2278 rc = avc_has_perm(tsec->sid, isec->sid, isec->sclass,
2279 FILE__RELABELFROM, &ad);
2280 if (rc)
2281 return rc;
2282
2283 rc = security_context_to_sid(value, size, &newsid);
2284 if (rc)
2285 return rc;
2286
2287 rc = avc_has_perm(tsec->sid, newsid, isec->sclass,
2288 FILE__RELABELTO, &ad);
2289 if (rc)
2290 return rc;
2291
2292 rc = security_validate_transition(isec->sid, newsid, tsec->sid,
2293 isec->sclass);
2294 if (rc)
2295 return rc;
2296
2297 return avc_has_perm(newsid,
2298 sbsec->sid,
2299 SECCLASS_FILESYSTEM,
2300 FILESYSTEM__ASSOCIATE,
2301 &ad);
2302}
2303
2304static void selinux_inode_post_setxattr(struct dentry *dentry, char *name,
2305 void *value, size_t size, int flags)
2306{
2307 struct inode *inode = dentry->d_inode;
2308 struct inode_security_struct *isec = inode->i_security;
2309 u32 newsid;
2310 int rc;
2311
2312 if (strcmp(name, XATTR_NAME_SELINUX)) {
2313 /* Not an attribute we recognize, so nothing to do. */
2314 return;
2315 }
2316
2317 rc = security_context_to_sid(value, size, &newsid);
2318 if (rc) {
2319 printk(KERN_WARNING "%s: unable to obtain SID for context "
2320 "%s, rc=%d\n", __FUNCTION__, (char*)value, -rc);
2321 return;
2322 }
2323
2324 isec->sid = newsid;
2325 return;
2326}
2327
2328static int selinux_inode_getxattr (struct dentry *dentry, char *name)
2329{
1da177e4
LT
2330 return dentry_has_perm(current, NULL, dentry, FILE__GETATTR);
2331}
2332
2333static int selinux_inode_listxattr (struct dentry *dentry)
2334{
2335 return dentry_has_perm(current, NULL, dentry, FILE__GETATTR);
2336}
2337
2338static int selinux_inode_removexattr (struct dentry *dentry, char *name)
2339{
2340 if (strcmp(name, XATTR_NAME_SELINUX)) {
2341 if (!strncmp(name, XATTR_SECURITY_PREFIX,
2342 sizeof XATTR_SECURITY_PREFIX - 1) &&
2343 !capable(CAP_SYS_ADMIN)) {
2344 /* A different attribute in the security namespace.
2345 Restrict to administrator. */
2346 return -EPERM;
2347 }
2348
2349 /* Not an attribute we recognize, so just check the
2350 ordinary setattr permission. Might want a separate
2351 permission for removexattr. */
2352 return dentry_has_perm(current, NULL, dentry, FILE__SETATTR);
2353 }
2354
2355 /* No one is allowed to remove a SELinux security label.
2356 You can change the label, but all data must be labeled. */
2357 return -EACCES;
2358}
2359
8c8570fb
DK
2360static const char *selinux_inode_xattr_getsuffix(void)
2361{
2362 return XATTR_SELINUX_SUFFIX;
2363}
2364
d381d8a9
JM
2365/*
2366 * Copy the in-core inode security context value to the user. If the
2367 * getxattr() prior to this succeeded, check to see if we need to
2368 * canonicalize the value to be finally returned to the user.
2369 *
2370 * Permission check is handled by selinux_inode_getxattr hook.
2371 */
7306a0b9 2372static int selinux_inode_getsecurity(const struct inode *inode, const char *name, void *buffer, size_t size, int err)
1da177e4
LT
2373{
2374 struct inode_security_struct *isec = inode->i_security;
d381d8a9 2375
8c8570fb
DK
2376 if (strcmp(name, XATTR_SELINUX_SUFFIX))
2377 return -EOPNOTSUPP;
d381d8a9 2378
8c8570fb 2379 return selinux_getsecurity(isec->sid, buffer, size);
1da177e4
LT
2380}
2381
2382static int selinux_inode_setsecurity(struct inode *inode, const char *name,
2383 const void *value, size_t size, int flags)
2384{
2385 struct inode_security_struct *isec = inode->i_security;
2386 u32 newsid;
2387 int rc;
2388
2389 if (strcmp(name, XATTR_SELINUX_SUFFIX))
2390 return -EOPNOTSUPP;
2391
2392 if (!value || !size)
2393 return -EACCES;
2394
2395 rc = security_context_to_sid((void*)value, size, &newsid);
2396 if (rc)
2397 return rc;
2398
2399 isec->sid = newsid;
2400 return 0;
2401}
2402
2403static int selinux_inode_listsecurity(struct inode *inode, char *buffer, size_t buffer_size)
2404{
2405 const int len = sizeof(XATTR_NAME_SELINUX);
2406 if (buffer && len <= buffer_size)
2407 memcpy(buffer, XATTR_NAME_SELINUX, len);
2408 return len;
2409}
2410
2411/* file security operations */
2412
2413static int selinux_file_permission(struct file *file, int mask)
2414{
7420ed23 2415 int rc;
1da177e4
LT
2416 struct inode *inode = file->f_dentry->d_inode;
2417
2418 if (!mask) {
2419 /* No permission to check. Existence test. */
2420 return 0;
2421 }
2422
2423 /* file_mask_to_av won't add FILE__WRITE if MAY_APPEND is set */
2424 if ((file->f_flags & O_APPEND) && (mask & MAY_WRITE))
2425 mask |= MAY_APPEND;
2426
7420ed23
VY
2427 rc = file_has_perm(current, file,
2428 file_mask_to_av(inode->i_mode, mask));
2429 if (rc)
2430 return rc;
2431
2432 return selinux_netlbl_inode_permission(inode, mask);
1da177e4
LT
2433}
2434
2435static int selinux_file_alloc_security(struct file *file)
2436{
2437 return file_alloc_security(file);
2438}
2439
2440static void selinux_file_free_security(struct file *file)
2441{
2442 file_free_security(file);
2443}
2444
2445static int selinux_file_ioctl(struct file *file, unsigned int cmd,
2446 unsigned long arg)
2447{
2448 int error = 0;
2449
2450 switch (cmd) {
2451 case FIONREAD:
2452 /* fall through */
2453 case FIBMAP:
2454 /* fall through */
2455 case FIGETBSZ:
2456 /* fall through */
2457 case EXT2_IOC_GETFLAGS:
2458 /* fall through */
2459 case EXT2_IOC_GETVERSION:
2460 error = file_has_perm(current, file, FILE__GETATTR);
2461 break;
2462
2463 case EXT2_IOC_SETFLAGS:
2464 /* fall through */
2465 case EXT2_IOC_SETVERSION:
2466 error = file_has_perm(current, file, FILE__SETATTR);
2467 break;
2468
2469 /* sys_ioctl() checks */
2470 case FIONBIO:
2471 /* fall through */
2472 case FIOASYNC:
2473 error = file_has_perm(current, file, 0);
2474 break;
2475
2476 case KDSKBENT:
2477 case KDSKBSENT:
2478 error = task_has_capability(current,CAP_SYS_TTY_CONFIG);
2479 break;
2480
2481 /* default case assumes that the command will go
2482 * to the file's ioctl() function.
2483 */
2484 default:
2485 error = file_has_perm(current, file, FILE__IOCTL);
2486
2487 }
2488 return error;
2489}
2490
2491static int file_map_prot_check(struct file *file, unsigned long prot, int shared)
2492{
2493#ifndef CONFIG_PPC32
2494 if ((prot & PROT_EXEC) && (!file || (!shared && (prot & PROT_WRITE)))) {
2495 /*
2496 * We are making executable an anonymous mapping or a
2497 * private file mapping that will also be writable.
2498 * This has an additional check.
2499 */
2500 int rc = task_has_perm(current, current, PROCESS__EXECMEM);
2501 if (rc)
2502 return rc;
2503 }
2504#endif
2505
2506 if (file) {
2507 /* read access is always possible with a mapping */
2508 u32 av = FILE__READ;
2509
2510 /* write access only matters if the mapping is shared */
2511 if (shared && (prot & PROT_WRITE))
2512 av |= FILE__WRITE;
2513
2514 if (prot & PROT_EXEC)
2515 av |= FILE__EXECUTE;
2516
2517 return file_has_perm(current, file, av);
2518 }
2519 return 0;
2520}
2521
2522static int selinux_file_mmap(struct file *file, unsigned long reqprot,
2523 unsigned long prot, unsigned long flags)
2524{
2525 int rc;
2526
2527 rc = secondary_ops->file_mmap(file, reqprot, prot, flags);
2528 if (rc)
2529 return rc;
2530
2531 if (selinux_checkreqprot)
2532 prot = reqprot;
2533
2534 return file_map_prot_check(file, prot,
2535 (flags & MAP_TYPE) == MAP_SHARED);
2536}
2537
2538static int selinux_file_mprotect(struct vm_area_struct *vma,
2539 unsigned long reqprot,
2540 unsigned long prot)
2541{
2542 int rc;
2543
2544 rc = secondary_ops->file_mprotect(vma, reqprot, prot);
2545 if (rc)
2546 return rc;
2547
2548 if (selinux_checkreqprot)
2549 prot = reqprot;
2550
2551#ifndef CONFIG_PPC32
db4c9641
SS
2552 if ((prot & PROT_EXEC) && !(vma->vm_flags & VM_EXEC)) {
2553 rc = 0;
2554 if (vma->vm_start >= vma->vm_mm->start_brk &&
2555 vma->vm_end <= vma->vm_mm->brk) {
2556 rc = task_has_perm(current, current,
2557 PROCESS__EXECHEAP);
2558 } else if (!vma->vm_file &&
2559 vma->vm_start <= vma->vm_mm->start_stack &&
2560 vma->vm_end >= vma->vm_mm->start_stack) {
2561 rc = task_has_perm(current, current, PROCESS__EXECSTACK);
2562 } else if (vma->vm_file && vma->anon_vma) {
2563 /*
2564 * We are making executable a file mapping that has
2565 * had some COW done. Since pages might have been
2566 * written, check ability to execute the possibly
2567 * modified content. This typically should only
2568 * occur for text relocations.
2569 */
2570 rc = file_has_perm(current, vma->vm_file,
2571 FILE__EXECMOD);
2572 }