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Capabilities: BUG when an invalid capability is requested
[linux.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, <[email protected]>
828dfe1d
EP		 7 * Chris Vance, <[email protected]>
8 * Wayne Salamon, <[email protected]>
9 * James Morris <[email protected]>
1da177e4
LT		 10 *
11 * Copyright (C) 2001,2002 Networks Associates Technology, Inc.
2069f457
EP		 12 * Copyright (C) 2003-2008 Red Hat, Inc., James Morris <[email protected]>
13 * Eric Paris <[email protected]>
1da177e4 14 * Copyright (C) 2004-2005 Trusted Computer Solutions, Inc.
828dfe1d 15 * <[email protected]>
effad8df 16 * Copyright (C) 2006, 2007 Hewlett-Packard Development Company, L.P.
828dfe1d 17 * Paul Moore <[email protected]>
788e7dd4 18 * Copyright (C) 2007 Hitachi Software Engineering Co., Ltd.
828dfe1d 19 * Yuichi Nakamura <[email protected]>
1da177e4
LT		 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,
828dfe1d 23 * as published by the Free Software Foundation.
1da177e4
LT		 24 */
25
1da177e4
LT		 26#include <linux/init.h>
27#include <linux/kernel.h>
0d094efe 28#include <linux/tracehook.h>
1da177e4
LT		 29#include <linux/errno.h>
30#include <linux/sched.h>
31#include <linux/security.h>
32#include <linux/xattr.h>
33#include <linux/capability.h>
34#include <linux/unistd.h>
35#include <linux/mm.h>
36#include <linux/mman.h>
37#include <linux/slab.h>
38#include <linux/pagemap.h>
39#include <linux/swap.h>
1da177e4
LT		 40#include <linux/spinlock.h>
41#include <linux/syscalls.h>
42#include <linux/file.h>
9f3acc31 43#include <linux/fdtable.h>
1da177e4
LT		 44#include <linux/namei.h>
45#include <linux/mount.h>
1da177e4 46#include <linux/proc_fs.h>
1da177e4
LT		 47#include <linux/netfilter_ipv4.h>
48#include <linux/netfilter_ipv6.h>
49#include <linux/tty.h>
50#include <net/icmp.h>
227b60f5 51#include <net/ip.h> /* for local_port_range[] */
1da177e4 52#include <net/tcp.h> /* struct or_callable used in sock_rcv_skb */
220deb96 53#include <net/net_namespace.h>
d621d35e 54#include <net/netlabel.h>
f5269710 55#include <linux/uaccess.h>
1da177e4 56#include <asm/ioctls.h>
d621d35e 57#include <asm/atomic.h>
1da177e4
LT		 58#include <linux/bitops.h>
59#include <linux/interrupt.h>
60#include <linux/netdevice.h> /* for network interface checks */
61#include <linux/netlink.h>
62#include <linux/tcp.h>
63#include <linux/udp.h>
2ee92d46 64#include <linux/dccp.h>
1da177e4
LT		 65#include <linux/quota.h>
66#include <linux/un.h> /* for Unix socket types */
67#include <net/af_unix.h> /* for Unix socket types */
68#include <linux/parser.h>
69#include <linux/nfs_mount.h>
70#include <net/ipv6.h>
71#include <linux/hugetlb.h>
72#include <linux/personality.h>
73#include <linux/sysctl.h>
74#include <linux/audit.h>
6931dfc9 75#include <linux/string.h>
877ce7c1 76#include <linux/selinux.h>
23970741 77#include <linux/mutex.h>
f06febc9 78#include <linux/posix-timers.h>
1da177e4
LT		 79
80#include "avc.h"
81#include "objsec.h"
82#include "netif.h"
224dfbd8 83#include "netnode.h"
3e112172 84#include "netport.h"
d28d1e08 85#include "xfrm.h"
c60475bf 86#include "netlabel.h"
9d57a7f9 87#include "audit.h"
1da177e4
LT		 88
89#define XATTR_SELINUX_SUFFIX "selinux"
90#define XATTR_NAME_SELINUX XATTR_SECURITY_PREFIX XATTR_SELINUX_SUFFIX
91
c9180a57
EP		 92#define NUM_SEL_MNT_OPTS 4
93
1da177e4
LT		 94extern unsigned int policydb_loaded_version;
95extern int selinux_nlmsg_lookup(u16 sclass, u16 nlmsg_type, u32 *perm);
4e5ab4cb 96extern int selinux_compat_net;
20510f2f 97extern struct security_operations *security_ops;
1da177e4 98
d621d35e
PM		 99/* SECMARK reference count */
100atomic_t selinux_secmark_refcount = ATOMIC_INIT(0);
101
1da177e4 102#ifdef CONFIG_SECURITY_SELINUX_DEVELOP
828dfe1d 103int selinux_enforcing;
1da177e4
LT		 104
105static int __init enforcing_setup(char *str)
106{
f5269710
EP		 107 unsigned long enforcing;
108 if (!strict_strtoul(str, 0, &enforcing))
109 selinux_enforcing = enforcing ? 1 : 0;
1da177e4
LT		 110 return 1;
111}
112__setup("enforcing=", enforcing_setup);
113#endif
114
115#ifdef CONFIG_SECURITY_SELINUX_BOOTPARAM
116int selinux_enabled = CONFIG_SECURITY_SELINUX_BOOTPARAM_VALUE;
117
118static int __init selinux_enabled_setup(char *str)
119{
f5269710
EP		 120 unsigned long enabled;
121 if (!strict_strtoul(str, 0, &enabled))
122 selinux_enabled = enabled ? 1 : 0;
1da177e4
LT		 123 return 1;
124}
125__setup("selinux=", selinux_enabled_setup);
30d55280
SS		 126#else
127int selinux_enabled = 1;
1da177e4
LT		 128#endif
129
1da177e4 130
6f0f0fd4
JM		 131/*
132 * Minimal support for a secondary security module,
133 * just to allow the use of the capability module.
134 */
828dfe1d 135static struct security_operations *secondary_ops;
1da177e4
LT		 136
137/* Lists of inode and superblock security structures initialized
138 before the policy was loaded. */
139static LIST_HEAD(superblock_security_head);
140static DEFINE_SPINLOCK(sb_security_lock);
141
e18b890b 142static struct kmem_cache *sel_inode_cache;
7cae7e26 143
d621d35e
PM		 144/**
145 * selinux_secmark_enabled - Check to see if SECMARK is currently enabled
146 *
147 * Description:
148 * This function checks the SECMARK reference counter to see if any SECMARK
149 * targets are currently configured, if the reference counter is greater than
150 * zero SECMARK is considered to be enabled. Returns true (1) if SECMARK is
151 * enabled, false (0) if SECMARK is disabled.
152 *
153 */
154static int selinux_secmark_enabled(void)
155{
156 return (atomic_read(&selinux_secmark_refcount) > 0);
157}
158
1da177e4
LT		 159/* Allocate and free functions for each kind of security blob. */
160
161static int task_alloc_security(struct task_struct *task)
162{
163 struct task_security_struct *tsec;
164
89d155ef 165 tsec = kzalloc(sizeof(struct task_security_struct), GFP_KERNEL);
1da177e4
LT		 166 if (!tsec)
167 return -ENOMEM;
168
0356357c 169 tsec->osid = tsec->sid = SECINITSID_UNLABELED;
1da177e4
LT		 170 task->security = tsec;
171
172 return 0;
173}
174
175static void task_free_security(struct task_struct *task)
176{
177 struct task_security_struct *tsec = task->security;
1da177e4
LT		 178 task->security = NULL;
179 kfree(tsec);
180}
181
182static int inode_alloc_security(struct inode *inode)
183{
184 struct task_security_struct *tsec = current->security;
185 struct inode_security_struct *isec;
186
a02fe132 187 isec = kmem_cache_zalloc(sel_inode_cache, GFP_NOFS);
1da177e4
LT		 188 if (!isec)
189 return -ENOMEM;
190
23970741 191 mutex_init(&isec->lock);
1da177e4 192 INIT_LIST_HEAD(&isec->list);
1da177e4
LT		 193 isec->inode = inode;
194 isec->sid = SECINITSID_UNLABELED;
195 isec->sclass = SECCLASS_FILE;
9ac49d22 196 isec->task_sid = tsec->sid;
1da177e4
LT		 197 inode->i_security = isec;
198
199 return 0;
200}
201
202static void inode_free_security(struct inode *inode)
203{
204 struct inode_security_struct *isec = inode->i_security;
205 struct superblock_security_struct *sbsec = inode->i_sb->s_security;
206
1da177e4
LT		 207 spin_lock(&sbsec->isec_lock);
208 if (!list_empty(&isec->list))
209 list_del_init(&isec->list);
210 spin_unlock(&sbsec->isec_lock);
211
212 inode->i_security = NULL;
7cae7e26 213 kmem_cache_free(sel_inode_cache, isec);
1da177e4
LT		 214}
215
216static int file_alloc_security(struct file *file)
217{
218 struct task_security_struct *tsec = current->security;
219 struct file_security_struct *fsec;
220
26d2a4be 221 fsec = kzalloc(sizeof(struct file_security_struct), GFP_KERNEL);
1da177e4
LT		 222 if (!fsec)
223 return -ENOMEM;
224
9ac49d22
SS		 225 fsec->sid = tsec->sid;
226 fsec->fown_sid = tsec->sid;
1da177e4
LT		 227 file->f_security = fsec;
228
229 return 0;
230}
231
232static void file_free_security(struct file *file)
233{
234 struct file_security_struct *fsec = file->f_security;
1da177e4
LT		 235 file->f_security = NULL;
236 kfree(fsec);
237}
238
239static int superblock_alloc_security(struct super_block *sb)
240{
241 struct superblock_security_struct *sbsec;
242
89d155ef 243 sbsec = kzalloc(sizeof(struct superblock_security_struct), GFP_KERNEL);
1da177e4
LT		 244 if (!sbsec)
245 return -ENOMEM;
246
bc7e982b 247 mutex_init(&sbsec->lock);
1da177e4
LT		 248 INIT_LIST_HEAD(&sbsec->list);
249 INIT_LIST_HEAD(&sbsec->isec_head);
250 spin_lock_init(&sbsec->isec_lock);
1da177e4
LT		 251 sbsec->sb = sb;
252 sbsec->sid = SECINITSID_UNLABELED;
253 sbsec->def_sid = SECINITSID_FILE;
c312feb2 254 sbsec->mntpoint_sid = SECINITSID_UNLABELED;
1da177e4
LT		 255 sb->s_security = sbsec;
256
257 return 0;
258}
259
260static void superblock_free_security(struct super_block *sb)
261{
262 struct superblock_security_struct *sbsec = sb->s_security;
263
1da177e4
LT		 264 spin_lock(&sb_security_lock);
265 if (!list_empty(&sbsec->list))
266 list_del_init(&sbsec->list);
267 spin_unlock(&sb_security_lock);
268
269 sb->s_security = NULL;
270 kfree(sbsec);
271}
272
7d877f3b 273static int sk_alloc_security(struct sock *sk, int family, gfp_t priority)
1da177e4
LT		 274{
275 struct sk_security_struct *ssec;
276
89d155ef 277 ssec = kzalloc(sizeof(*ssec), priority);
1da177e4
LT		 278 if (!ssec)
279 return -ENOMEM;
280
1da177e4 281 ssec->peer_sid = SECINITSID_UNLABELED;
892c141e 282 ssec->sid = SECINITSID_UNLABELED;
1da177e4
LT		 283 sk->sk_security = ssec;
284
f74af6e8 285 selinux_netlbl_sk_security_reset(ssec, family);
99f59ed0 286
1da177e4
LT		 287 return 0;
288}
289
290static void sk_free_security(struct sock *sk)
291{
292 struct sk_security_struct *ssec = sk->sk_security;
293
1da177e4 294 sk->sk_security = NULL;
6c5b3fc0 295 selinux_netlbl_sk_security_free(ssec);
1da177e4
LT		 296 kfree(ssec);
297}
1da177e4
LT		 298
299/* The security server must be initialized before
300 any labeling or access decisions can be provided. */
301extern int ss_initialized;
302
303/* The file system's label must be initialized prior to use. */
304
305static char *labeling_behaviors[6] = {
306 "uses xattr",
307 "uses transition SIDs",
308 "uses task SIDs",
309 "uses genfs_contexts",
310 "not configured for labeling",
311 "uses mountpoint labeling",
312};
313
314static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dentry);
315
316static inline int inode_doinit(struct inode *inode)
317{
318 return inode_doinit_with_dentry(inode, NULL);
319}
320
321enum {
31e87930 322 Opt_error = -1,
1da177e4
LT		 323 Opt_context = 1,
324 Opt_fscontext = 2,
c9180a57
EP		 325 Opt_defcontext = 3,
326 Opt_rootcontext = 4,
1da177e4
LT		 327};
328
a447c093 329static const match_table_t tokens = {
832cbd9a
EP		 330 {Opt_context, CONTEXT_STR "%s"},
331 {Opt_fscontext, FSCONTEXT_STR "%s"},
332 {Opt_defcontext, DEFCONTEXT_STR "%s"},
333 {Opt_rootcontext, ROOTCONTEXT_STR "%s"},
31e87930 334 {Opt_error, NULL},
1da177e4
LT		 335};
336
337#define SEL_MOUNT_FAIL_MSG "SELinux: duplicate or incompatible mount options\n"
338
c312feb2
EP		 339static int may_context_mount_sb_relabel(u32 sid,
340 struct superblock_security_struct *sbsec,
341 struct task_security_struct *tsec)
342{
343 int rc;
344
345 rc = avc_has_perm(tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM,
346 FILESYSTEM__RELABELFROM, NULL);
347 if (rc)
348 return rc;
349
350 rc = avc_has_perm(tsec->sid, sid, SECCLASS_FILESYSTEM,
351 FILESYSTEM__RELABELTO, NULL);
352 return rc;
353}
354
0808925e
EP		 355static int may_context_mount_inode_relabel(u32 sid,
356 struct superblock_security_struct *sbsec,
357 struct task_security_struct *tsec)
358{
359 int rc;
360 rc = avc_has_perm(tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM,
361 FILESYSTEM__RELABELFROM, NULL);
362 if (rc)
363 return rc;
364
365 rc = avc_has_perm(sid, sbsec->sid, SECCLASS_FILESYSTEM,
366 FILESYSTEM__ASSOCIATE, NULL);
367 return rc;
368}
369
c9180a57 370static int sb_finish_set_opts(struct super_block *sb)
1da177e4 371{
1da177e4 372 struct superblock_security_struct *sbsec = sb->s_security;
c9180a57
EP		 373 struct dentry *root = sb->s_root;
374 struct inode *root_inode = root->d_inode;
375 int rc = 0;
1da177e4 376
c9180a57
EP		 377 if (sbsec->behavior == SECURITY_FS_USE_XATTR) {
378 /* Make sure that the xattr handler exists and that no
379 error other than -ENODATA is returned by getxattr on
380 the root directory. -ENODATA is ok, as this may be
381 the first boot of the SELinux kernel before we have
382 assigned xattr values to the filesystem. */
383 if (!root_inode->i_op->getxattr) {
384 printk(KERN_WARNING "SELinux: (dev %s, type %s) has no "
385 "xattr support\n", sb->s_id, sb->s_type->name);
386 rc = -EOPNOTSUPP;
387 goto out;
388 }
389 rc = root_inode->i_op->getxattr(root, XATTR_NAME_SELINUX, NULL, 0);
390 if (rc < 0 && rc != -ENODATA) {
391 if (rc == -EOPNOTSUPP)
392 printk(KERN_WARNING "SELinux: (dev %s, type "
393 "%s) has no security xattr handler\n",
394 sb->s_id, sb->s_type->name);
395 else
396 printk(KERN_WARNING "SELinux: (dev %s, type "
397 "%s) getxattr errno %d\n", sb->s_id,
398 sb->s_type->name, -rc);
399 goto out;
400 }
401 }
1da177e4 402
c9180a57 403 sbsec->initialized = 1;
1da177e4 404
c9180a57
EP		 405 if (sbsec->behavior > ARRAY_SIZE(labeling_behaviors))
406 printk(KERN_ERR "SELinux: initialized (dev %s, type %s), unknown behavior\n",
407 sb->s_id, sb->s_type->name);
408 else
409 printk(KERN_DEBUG "SELinux: initialized (dev %s, type %s), %s\n",
410 sb->s_id, sb->s_type->name,
411 labeling_behaviors[sbsec->behavior-1]);
1da177e4 412
c9180a57
EP		 413 /* Initialize the root inode. */
414 rc = inode_doinit_with_dentry(root_inode, root);
1da177e4 415
c9180a57
EP		 416 /* Initialize any other inodes associated with the superblock, e.g.
417 inodes created prior to initial policy load or inodes created
418 during get_sb by a pseudo filesystem that directly
419 populates itself. */
420 spin_lock(&sbsec->isec_lock);
421next_inode:
422 if (!list_empty(&sbsec->isec_head)) {
423 struct inode_security_struct *isec =
424 list_entry(sbsec->isec_head.next,
425 struct inode_security_struct, list);
426 struct inode *inode = isec->inode;
427 spin_unlock(&sbsec->isec_lock);
428 inode = igrab(inode);
429 if (inode) {
430 if (!IS_PRIVATE(inode))
431 inode_doinit(inode);
432 iput(inode);
433 }
434 spin_lock(&sbsec->isec_lock);
435 list_del_init(&isec->list);
436 goto next_inode;
437 }
438 spin_unlock(&sbsec->isec_lock);
439out:
440 return rc;
441}
1da177e4 442
c9180a57
EP		 443/*
444 * This function should allow an FS to ask what it's mount security
445 * options were so it can use those later for submounts, displaying
446 * mount options, or whatever.
447 */
448static int selinux_get_mnt_opts(const struct super_block *sb,
e0007529 449 struct security_mnt_opts *opts)
c9180a57
EP		 450{
451 int rc = 0, i;
452 struct superblock_security_struct *sbsec = sb->s_security;
453 char *context = NULL;
454 u32 len;
455 char tmp;
1da177e4 456
e0007529 457 security_init_mnt_opts(opts);
1da177e4 458
c9180a57
EP		 459 if (!sbsec->initialized)
460 return -EINVAL;
1da177e4 461
c9180a57
EP		 462 if (!ss_initialized)
463 return -EINVAL;
1da177e4 464
c9180a57
EP		 465 /*
466 * if we ever use sbsec flags for anything other than tracking mount
467 * settings this is going to need a mask
468 */
469 tmp = sbsec->flags;
470 /* count the number of mount options for this sb */
471 for (i = 0; i < 8; i++) {
472 if (tmp & 0x01)
e0007529 473 opts->num_mnt_opts++;
c9180a57
EP		 474 tmp >>= 1;
475 }
1da177e4 476
e0007529
EP		 477 opts->mnt_opts = kcalloc(opts->num_mnt_opts, sizeof(char *), GFP_ATOMIC);
478 if (!opts->mnt_opts) {
c9180a57
EP		 479 rc = -ENOMEM;
480 goto out_free;
481 }
1da177e4 482
e0007529
EP		 483 opts->mnt_opts_flags = kcalloc(opts->num_mnt_opts, sizeof(int), GFP_ATOMIC);
484 if (!opts->mnt_opts_flags) {
c9180a57
EP		 485 rc = -ENOMEM;
486 goto out_free;
487 }
1da177e4 488
c9180a57
EP		 489 i = 0;
490 if (sbsec->flags & FSCONTEXT_MNT) {
491 rc = security_sid_to_context(sbsec->sid, &context, &len);
492 if (rc)
493 goto out_free;
e0007529
EP		 494 opts->mnt_opts[i] = context;
495 opts->mnt_opts_flags[i++] = FSCONTEXT_MNT;
c9180a57
EP		 496 }
497 if (sbsec->flags & CONTEXT_MNT) {
498 rc = security_sid_to_context(sbsec->mntpoint_sid, &context, &len);
499 if (rc)
500 goto out_free;
e0007529
EP		 501 opts->mnt_opts[i] = context;
502 opts->mnt_opts_flags[i++] = CONTEXT_MNT;
c9180a57
EP		 503 }
504 if (sbsec->flags & DEFCONTEXT_MNT) {
505 rc = security_sid_to_context(sbsec->def_sid, &context, &len);
506 if (rc)
507 goto out_free;
e0007529
EP		 508 opts->mnt_opts[i] = context;
509 opts->mnt_opts_flags[i++] = DEFCONTEXT_MNT;
c9180a57
EP		 510 }
511 if (sbsec->flags & ROOTCONTEXT_MNT) {
512 struct inode *root = sbsec->sb->s_root->d_inode;
513 struct inode_security_struct *isec = root->i_security;
0808925e 514
c9180a57
EP		 515 rc = security_sid_to_context(isec->sid, &context, &len);
516 if (rc)
517 goto out_free;
e0007529
EP		 518 opts->mnt_opts[i] = context;
519 opts->mnt_opts_flags[i++] = ROOTCONTEXT_MNT;
c9180a57 520 }
1da177e4 521
e0007529 522 BUG_ON(i != opts->num_mnt_opts);
1da177e4 523
c9180a57
EP		 524 return 0;
525
526out_free:
e0007529 527 security_free_mnt_opts(opts);
c9180a57
EP		 528 return rc;
529}
1da177e4 530
c9180a57
EP		 531static int bad_option(struct superblock_security_struct *sbsec, char flag,
532 u32 old_sid, u32 new_sid)
533{
534 /* check if the old mount command had the same options */
535 if (sbsec->initialized)
536 if (!(sbsec->flags & flag) ||
537 (old_sid != new_sid))
538 return 1;
539
540 /* check if we were passed the same options twice,
541 * aka someone passed context=a,context=b
542 */
543 if (!sbsec->initialized)
544 if (sbsec->flags & flag)
545 return 1;
546 return 0;
547}
e0007529 548
c9180a57
EP		 549/*
550 * Allow filesystems with binary mount data to explicitly set mount point
551 * labeling information.
552 */
e0007529
EP		 553static int selinux_set_mnt_opts(struct super_block *sb,
554 struct security_mnt_opts *opts)
c9180a57
EP		 555{
556 int rc = 0, i;
557 struct task_security_struct *tsec = current->security;
558 struct superblock_security_struct *sbsec = sb->s_security;
559 const char *name = sb->s_type->name;
089be43e
JM		 560 struct inode *inode = sbsec->sb->s_root->d_inode;
561 struct inode_security_struct *root_isec = inode->i_security;
c9180a57
EP		 562 u32 fscontext_sid = 0, context_sid = 0, rootcontext_sid = 0;
563 u32 defcontext_sid = 0;
e0007529
EP		 564 char **mount_options = opts->mnt_opts;
565 int *flags = opts->mnt_opts_flags;
566 int num_opts = opts->num_mnt_opts;
c9180a57
EP		 567
568 mutex_lock(&sbsec->lock);
569
570 if (!ss_initialized) {
571 if (!num_opts) {
572 /* Defer initialization until selinux_complete_init,
573 after the initial policy is loaded and the security
574 server is ready to handle calls. */
575 spin_lock(&sb_security_lock);
576 if (list_empty(&sbsec->list))
577 list_add(&sbsec->list, &superblock_security_head);
578 spin_unlock(&sb_security_lock);
579 goto out;
580 }
581 rc = -EINVAL;
744ba35e
EP		 582 printk(KERN_WARNING "SELinux: Unable to set superblock options "
583 "before the security server is initialized\n");
1da177e4 584 goto out;
c9180a57 585 }
1da177e4 586
e0007529
EP		 587 /*
588 * Binary mount data FS will come through this function twice. Once
589 * from an explicit call and once from the generic calls from the vfs.
590 * Since the generic VFS calls will not contain any security mount data
591 * we need to skip the double mount verification.
592 *
593 * This does open a hole in which we will not notice if the first
594 * mount using this sb set explict options and a second mount using
595 * this sb does not set any security options. (The first options
596 * will be used for both mounts)
597 */
598 if (sbsec->initialized && (sb->s_type->fs_flags & FS_BINARY_MOUNTDATA)
599 && (num_opts == 0))
f5269710 600 goto out;
e0007529 601
c9180a57
EP		 602 /*
603 * parse the mount options, check if they are valid sids.
604 * also check if someone is trying to mount the same sb more
605 * than once with different security options.
606 */
607 for (i = 0; i < num_opts; i++) {
608 u32 sid;
609 rc = security_context_to_sid(mount_options[i],
610 strlen(mount_options[i]), &sid);
1da177e4
LT		 611 if (rc) {
612 printk(KERN_WARNING "SELinux: security_context_to_sid"
613 "(%s) failed for (dev %s, type %s) errno=%d\n",
c9180a57
EP		 614 mount_options[i], sb->s_id, name, rc);
615 goto out;
616 }
617 switch (flags[i]) {
618 case FSCONTEXT_MNT:
619 fscontext_sid = sid;
620
621 if (bad_option(sbsec, FSCONTEXT_MNT, sbsec->sid,
622 fscontext_sid))
623 goto out_double_mount;
624
625 sbsec->flags |= FSCONTEXT_MNT;
626 break;
627 case CONTEXT_MNT:
628 context_sid = sid;
629
630 if (bad_option(sbsec, CONTEXT_MNT, sbsec->mntpoint_sid,
631 context_sid))
632 goto out_double_mount;
633
634 sbsec->flags |= CONTEXT_MNT;
635 break;
636 case ROOTCONTEXT_MNT:
637 rootcontext_sid = sid;
638
639 if (bad_option(sbsec, ROOTCONTEXT_MNT, root_isec->sid,
640 rootcontext_sid))
641 goto out_double_mount;
642
643 sbsec->flags |= ROOTCONTEXT_MNT;
644
645 break;
646 case DEFCONTEXT_MNT:
647 defcontext_sid = sid;
648
649 if (bad_option(sbsec, DEFCONTEXT_MNT, sbsec->def_sid,
650 defcontext_sid))
651 goto out_double_mount;
652
653 sbsec->flags |= DEFCONTEXT_MNT;
654
655 break;
656 default:
657 rc = -EINVAL;
658 goto out;
1da177e4 659 }
c9180a57
EP		 660 }
661
662 if (sbsec->initialized) {
663 /* previously mounted with options, but not on this attempt? */
664 if (sbsec->flags && !num_opts)
665 goto out_double_mount;
666 rc = 0;
667 goto out;
668 }
669
089be43e 670 if (strcmp(sb->s_type->name, "proc") == 0)
c9180a57
EP		 671 sbsec->proc = 1;
672
673 /* Determine the labeling behavior to use for this filesystem type. */
089be43e 674 rc = security_fs_use(sb->s_type->name, &sbsec->behavior, &sbsec->sid);
c9180a57
EP		 675 if (rc) {
676 printk(KERN_WARNING "%s: security_fs_use(%s) returned %d\n",
089be43e 677 __func__, sb->s_type->name, rc);
c9180a57
EP		 678 goto out;
679 }
1da177e4 680
c9180a57
EP		 681 /* sets the context of the superblock for the fs being mounted. */
682 if (fscontext_sid) {
683
684 rc = may_context_mount_sb_relabel(fscontext_sid, sbsec, tsec);
1da177e4 685 if (rc)
c9180a57 686 goto out;
1da177e4 687
c9180a57 688 sbsec->sid = fscontext_sid;
c312feb2
EP		 689 }
690
691 /*
692 * Switch to using mount point labeling behavior.
693 * sets the label used on all file below the mountpoint, and will set
694 * the superblock context if not already set.
695 */
c9180a57
EP		 696 if (context_sid) {
697 if (!fscontext_sid) {
698 rc = may_context_mount_sb_relabel(context_sid, sbsec, tsec);
b04ea3ce 699 if (rc)
c9180a57
EP		 700 goto out;
701 sbsec->sid = context_sid;
b04ea3ce 702 } else {
c9180a57 703 rc = may_context_mount_inode_relabel(context_sid, sbsec, tsec);
b04ea3ce 704 if (rc)
c9180a57 705 goto out;
b04ea3ce 706 }
c9180a57
EP		 707 if (!rootcontext_sid)
708 rootcontext_sid = context_sid;
1da177e4 709
c9180a57 710 sbsec->mntpoint_sid = context_sid;
c312feb2 711 sbsec->behavior = SECURITY_FS_USE_MNTPOINT;
1da177e4
LT		 712 }
713
c9180a57
EP		 714 if (rootcontext_sid) {
715 rc = may_context_mount_inode_relabel(rootcontext_sid, sbsec, tsec);
0808925e 716 if (rc)
c9180a57 717 goto out;
0808925e 718
c9180a57
EP		 719 root_isec->sid = rootcontext_sid;
720 root_isec->initialized = 1;
0808925e
EP		 721 }
722
c9180a57
EP		 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;
1da177e4
LT		 729 }
730
c9180a57
EP		 731 if (defcontext_sid != sbsec->def_sid) {
732 rc = may_context_mount_inode_relabel(defcontext_sid,
733 sbsec, tsec);
734 if (rc)
735 goto out;
736 }
1da177e4 737
c9180a57 738 sbsec->def_sid = defcontext_sid;
1da177e4
LT		 739 }
740
c9180a57 741 rc = sb_finish_set_opts(sb);
1da177e4 742out:
c9180a57 743 mutex_unlock(&sbsec->lock);
1da177e4 744 return rc;
c9180a57
EP		 745out_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;
1da177e4
LT		 750}
751
c9180a57
EP		 752static void selinux_sb_clone_mnt_opts(const struct super_block *oldsb,
753 struct super_block *newsb)
1da177e4 754{
c9180a57
EP		 755 const struct superblock_security_struct *oldsbsec = oldsb->s_security;
756 struct superblock_security_struct *newsbsec = newsb->s_security;
1da177e4 757
c9180a57
EP		 758 int set_fscontext = (oldsbsec->flags & FSCONTEXT_MNT);
759 int set_context = (oldsbsec->flags & CONTEXT_MNT);
760 int set_rootcontext = (oldsbsec->flags & ROOTCONTEXT_MNT);
1da177e4 761
0f5e6420
EP		 762 /*
763 * if the parent was able to be mounted it clearly had no special lsm
764 * mount options. thus we can safely put this sb on the list and deal
765 * with it later
766 */
767 if (!ss_initialized) {
768 spin_lock(&sb_security_lock);
769 if (list_empty(&newsbsec->list))
770 list_add(&newsbsec->list, &superblock_security_head);
771 spin_unlock(&sb_security_lock);
772 return;
773 }
c9180a57 774
c9180a57
EP		 775 /* how can we clone if the old one wasn't set up?? */
776 BUG_ON(!oldsbsec->initialized);
777
5a552617
EP		 778 /* if fs is reusing a sb, just let its options stand... */
779 if (newsbsec->initialized)
780 return;
781
c9180a57
EP		 782 mutex_lock(&newsbsec->lock);
783
784 newsbsec->flags = oldsbsec->flags;
785
786 newsbsec->sid = oldsbsec->sid;
787 newsbsec->def_sid = oldsbsec->def_sid;
788 newsbsec->behavior = oldsbsec->behavior;
789
790 if (set_context) {
791 u32 sid = oldsbsec->mntpoint_sid;
792
793 if (!set_fscontext)
794 newsbsec->sid = sid;
795 if (!set_rootcontext) {
796 struct inode *newinode = newsb->s_root->d_inode;
797 struct inode_security_struct *newisec = newinode->i_security;
798 newisec->sid = sid;
799 }
800 newsbsec->mntpoint_sid = sid;
1da177e4 801 }
c9180a57
EP		 802 if (set_rootcontext) {
803 const struct inode *oldinode = oldsb->s_root->d_inode;
804 const struct inode_security_struct *oldisec = oldinode->i_security;
805 struct inode *newinode = newsb->s_root->d_inode;
806 struct inode_security_struct *newisec = newinode->i_security;
1da177e4 807
c9180a57 808 newisec->sid = oldisec->sid;
1da177e4
LT		 809 }
810
c9180a57
EP		 811 sb_finish_set_opts(newsb);
812 mutex_unlock(&newsbsec->lock);
813}
814
2e1479d9
AB		 815static int selinux_parse_opts_str(char *options,
816 struct security_mnt_opts *opts)
c9180a57 817{
e0007529 818 char *p;
c9180a57
EP		 819 char *context = NULL, *defcontext = NULL;
820 char *fscontext = NULL, *rootcontext = NULL;
e0007529 821 int rc, num_mnt_opts = 0;
1da177e4 822
e0007529 823 opts->num_mnt_opts = 0;
1da177e4 824
c9180a57
EP		 825 /* Standard string-based options. */
826 while ((p = strsep(&options, "|")) != NULL) {
827 int token;
828 substring_t args[MAX_OPT_ARGS];
1da177e4 829
c9180a57
EP		 830 if (!*p)
831 continue;
1da177e4 832
c9180a57 833 token = match_token(p, tokens, args);
1da177e4 834
c9180a57
EP		 835 switch (token) {
836 case Opt_context:
837 if (context || defcontext) {
838 rc = -EINVAL;
839 printk(KERN_WARNING SEL_MOUNT_FAIL_MSG);
840 goto out_err;
841 }
842 context = match_strdup(&args[0]);
843 if (!context) {
844 rc = -ENOMEM;
845 goto out_err;
846 }
847 break;
848
849 case Opt_fscontext:
850 if (fscontext) {
851 rc = -EINVAL;
852 printk(KERN_WARNING SEL_MOUNT_FAIL_MSG);
853 goto out_err;
854 }
855 fscontext = match_strdup(&args[0]);
856 if (!fscontext) {
857 rc = -ENOMEM;
858 goto out_err;
859 }
860 break;
861
862 case Opt_rootcontext:
863 if (rootcontext) {
864 rc = -EINVAL;
865 printk(KERN_WARNING SEL_MOUNT_FAIL_MSG);
866 goto out_err;
867 }
868 rootcontext = match_strdup(&args[0]);
869 if (!rootcontext) {
870 rc = -ENOMEM;
871 goto out_err;
872 }
873 break;
874
875 case Opt_defcontext:
876 if (context || defcontext) {
877 rc = -EINVAL;
878 printk(KERN_WARNING SEL_MOUNT_FAIL_MSG);
879 goto out_err;
880 }
881 defcontext = match_strdup(&args[0]);
882 if (!defcontext) {
883 rc = -ENOMEM;
884 goto out_err;
885 }
886 break;
887
888 default:
889 rc = -EINVAL;
890 printk(KERN_WARNING "SELinux: unknown mount option\n");
891 goto out_err;
1da177e4 892
1da177e4 893 }
1da177e4 894 }
c9180a57 895
e0007529
EP		 896 rc = -ENOMEM;
897 opts->mnt_opts = kcalloc(NUM_SEL_MNT_OPTS, sizeof(char *), GFP_ATOMIC);
898 if (!opts->mnt_opts)
899 goto out_err;
900
901 opts->mnt_opts_flags = kcalloc(NUM_SEL_MNT_OPTS, sizeof(int), GFP_ATOMIC);
902 if (!opts->mnt_opts_flags) {
903 kfree(opts->mnt_opts);
904 goto out_err;
905 }
906
c9180a57 907 if (fscontext) {
e0007529
EP		 908 opts->mnt_opts[num_mnt_opts] = fscontext;
909 opts->mnt_opts_flags[num_mnt_opts++] = FSCONTEXT_MNT;
c9180a57
EP		 910 }
911 if (context) {
e0007529
EP		 912 opts->mnt_opts[num_mnt_opts] = context;
913 opts->mnt_opts_flags[num_mnt_opts++] = CONTEXT_MNT;
c9180a57
EP		 914 }
915 if (rootcontext) {
e0007529
EP		 916 opts->mnt_opts[num_mnt_opts] = rootcontext;
917 opts->mnt_opts_flags[num_mnt_opts++] = ROOTCONTEXT_MNT;
c9180a57
EP		 918 }
919 if (defcontext) {
e0007529
EP		 920 opts->mnt_opts[num_mnt_opts] = defcontext;
921 opts->mnt_opts_flags[num_mnt_opts++] = DEFCONTEXT_MNT;
c9180a57
EP		 922 }
923
e0007529
EP		 924 opts->num_mnt_opts = num_mnt_opts;
925 return 0;
926
c9180a57
EP		 927out_err:
928 kfree(context);
929 kfree(defcontext);
930 kfree(fscontext);
931 kfree(rootcontext);
1da177e4
LT		 932 return rc;
933}
e0007529
EP		 934/*
935 * string mount options parsing and call set the sbsec
936 */
937static int superblock_doinit(struct super_block *sb, void *data)
938{
939 int rc = 0;
940 char *options = data;
941 struct security_mnt_opts opts;
942
943 security_init_mnt_opts(&opts);
944
945 if (!data)
946 goto out;
947
948 BUG_ON(sb->s_type->fs_flags & FS_BINARY_MOUNTDATA);
949
950 rc = selinux_parse_opts_str(options, &opts);
951 if (rc)
952 goto out_err;
953
954out:
955 rc = selinux_set_mnt_opts(sb, &opts);
956
957out_err:
958 security_free_mnt_opts(&opts);
959 return rc;
960}
1da177e4 961
3583a711
AB		 962static void selinux_write_opts(struct seq_file *m,
963 struct security_mnt_opts *opts)
2069f457
EP		 964{
965 int i;
966 char *prefix;
967
968 for (i = 0; i < opts->num_mnt_opts; i++) {
969 char *has_comma = strchr(opts->mnt_opts[i], ',');
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 default:
985 BUG();
986 };
987 /* we need a comma before each option */
988 seq_putc(m, ',');
989 seq_puts(m, prefix);
990 if (has_comma)
991 seq_putc(m, '\"');
992 seq_puts(m, opts->mnt_opts[i]);
993 if (has_comma)
994 seq_putc(m, '\"');
995 }
996}
997
998static int selinux_sb_show_options(struct seq_file *m, struct super_block *sb)
999{
1000 struct security_mnt_opts opts;
1001 int rc;
1002
1003 rc = selinux_get_mnt_opts(sb, &opts);
383795c2
EP		 1004 if (rc) {
1005 /* before policy load we may get EINVAL, don't show anything */
1006 if (rc == -EINVAL)
1007 rc = 0;
2069f457 1008 return rc;
383795c2 1009 }
2069f457
EP		 1010
1011 selinux_write_opts(m, &opts);
1012
1013 security_free_mnt_opts(&opts);
1014
1015 return rc;
1016}
1017
1da177e4
LT		 1018static inline u16 inode_mode_to_security_class(umode_t mode)
1019{
1020 switch (mode & S_IFMT) {
1021 case S_IFSOCK:
1022 return SECCLASS_SOCK_FILE;
1023 case S_IFLNK:
1024 return SECCLASS_LNK_FILE;
1025 case S_IFREG:
1026 return SECCLASS_FILE;
1027 case S_IFBLK:
1028 return SECCLASS_BLK_FILE;
1029 case S_IFDIR:
1030 return SECCLASS_DIR;
1031 case S_IFCHR:
1032 return SECCLASS_CHR_FILE;
1033 case S_IFIFO:
1034 return SECCLASS_FIFO_FILE;
1035
1036 }
1037
1038 return SECCLASS_FILE;
1039}
1040
13402580
JM		 1041static inline int default_protocol_stream(int protocol)
1042{
1043 return (protocol == IPPROTO_IP || protocol == IPPROTO_TCP);
1044}
1045
1046static inline int default_protocol_dgram(int protocol)
1047{
1048 return (protocol == IPPROTO_IP || protocol == IPPROTO_UDP);
1049}
1050
1da177e4
LT		 1051static inline u16 socket_type_to_security_class(int family, int type, int protocol)
1052{
1053 switch (family) {
1054 case PF_UNIX:
1055 switch (type) {
1056 case SOCK_STREAM:
1057 case SOCK_SEQPACKET:
1058 return SECCLASS_UNIX_STREAM_SOCKET;
1059 case SOCK_DGRAM:
1060 return SECCLASS_UNIX_DGRAM_SOCKET;
1061 }
1062 break;
1063 case PF_INET:
1064 case PF_INET6:
1065 switch (type) {
1066 case SOCK_STREAM:
13402580
JM		 1067 if (default_protocol_stream(protocol))
1068 return SECCLASS_TCP_SOCKET;
1069 else
1070 return SECCLASS_RAWIP_SOCKET;
1da177e4 1071 case SOCK_DGRAM:
13402580
JM		 1072 if (default_protocol_dgram(protocol))
1073 return SECCLASS_UDP_SOCKET;
1074 else
1075 return SECCLASS_RAWIP_SOCKET;
2ee92d46
JM		 1076 case SOCK_DCCP:
1077 return SECCLASS_DCCP_SOCKET;
13402580 1078 default:
1da177e4
LT		 1079 return SECCLASS_RAWIP_SOCKET;
1080 }
1081 break;
1082 case PF_NETLINK:
1083 switch (protocol) {
1084 case NETLINK_ROUTE:
1085 return SECCLASS_NETLINK_ROUTE_SOCKET;
1086 case NETLINK_FIREWALL:
1087 return SECCLASS_NETLINK_FIREWALL_SOCKET;
216efaaa 1088 case NETLINK_INET_DIAG:
1da177e4
LT		 1089 return SECCLASS_NETLINK_TCPDIAG_SOCKET;
1090 case NETLINK_NFLOG:
1091 return SECCLASS_NETLINK_NFLOG_SOCKET;
1092 case NETLINK_XFRM:
1093 return SECCLASS_NETLINK_XFRM_SOCKET;
1094 case NETLINK_SELINUX:
1095 return SECCLASS_NETLINK_SELINUX_SOCKET;
1096 case NETLINK_AUDIT:
1097 return SECCLASS_NETLINK_AUDIT_SOCKET;
1098 case NETLINK_IP6_FW:
1099 return SECCLASS_NETLINK_IP6FW_SOCKET;
1100 case NETLINK_DNRTMSG:
1101 return SECCLASS_NETLINK_DNRT_SOCKET;
0c9b7942
JM		 1102 case NETLINK_KOBJECT_UEVENT:
1103 return SECCLASS_NETLINK_KOBJECT_UEVENT_SOCKET;
1da177e4
LT		 1104 default:
1105 return SECCLASS_NETLINK_SOCKET;
1106 }
1107 case PF_PACKET:
1108 return SECCLASS_PACKET_SOCKET;
1109 case PF_KEY:
1110 return SECCLASS_KEY_SOCKET;
3e3ff15e
CP		 1111 case PF_APPLETALK:
1112 return SECCLASS_APPLETALK_SOCKET;
1da177e4
LT		 1113 }
1114
1115 return SECCLASS_SOCKET;
1116}
1117
1118#ifdef CONFIG_PROC_FS
1119static int selinux_proc_get_sid(struct proc_dir_entry *de,
1120 u16 tclass,
1121 u32 *sid)
1122{
1123 int buflen, rc;
1124 char *buffer, *path, *end;
1125
828dfe1d 1126 buffer = (char *)__get_free_page(GFP_KERNEL);
1da177e4
LT		 1127 if (!buffer)
1128 return -ENOMEM;
1129
1130 buflen = PAGE_SIZE;
1131 end = buffer+buflen;
1132 *--end = '\0';
1133 buflen--;
1134 path = end-1;
1135 *path = '/';
1136 while (de && de != de->parent) {
1137 buflen -= de->namelen + 1;
1138 if (buflen < 0)
1139 break;
1140 end -= de->namelen;
1141 memcpy(end, de->name, de->namelen);
1142 *--end = '/';
1143 path = end;
1144 de = de->parent;
1145 }
1146 rc = security_genfs_sid("proc", path, tclass, sid);
1147 free_page((unsigned long)buffer);
1148 return rc;
1149}
1150#else
1151static int selinux_proc_get_sid(struct proc_dir_entry *de,
1152 u16 tclass,
1153 u32 *sid)
1154{
1155 return -EINVAL;
1156}
1157#endif
1158
1159/* The inode's security attributes must be initialized before first use. */
1160static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dentry)
1161{
1162 struct superblock_security_struct *sbsec = NULL;
1163 struct inode_security_struct *isec = inode->i_security;
1164 u32 sid;
1165 struct dentry *dentry;
1166#define INITCONTEXTLEN 255
1167 char *context = NULL;
1168 unsigned len = 0;
1169 int rc = 0;
1da177e4
LT		 1170
1171 if (isec->initialized)
1172 goto out;
1173
23970741 1174 mutex_lock(&isec->lock);
1da177e4 1175 if (isec->initialized)
23970741 1176 goto out_unlock;
1da177e4
LT		 1177
1178 sbsec = inode->i_sb->s_security;
1179 if (!sbsec->initialized) {
1180 /* Defer initialization until selinux_complete_init,
1181 after the initial policy is loaded and the security
1182 server is ready to handle calls. */
1183 spin_lock(&sbsec->isec_lock);
1184 if (list_empty(&isec->list))
1185 list_add(&isec->list, &sbsec->isec_head);
1186 spin_unlock(&sbsec->isec_lock);
23970741 1187 goto out_unlock;
1da177e4
LT		 1188 }
1189
1190 switch (sbsec->behavior) {
1191 case SECURITY_FS_USE_XATTR:
1192 if (!inode->i_op->getxattr) {
1193 isec->sid = sbsec->def_sid;
1194 break;
1195 }
1196
1197 /* Need a dentry, since the xattr API requires one.
1198 Life would be simpler if we could just pass the inode. */
1199 if (opt_dentry) {
1200 /* Called from d_instantiate or d_splice_alias. */
1201 dentry = dget(opt_dentry);
1202 } else {
1203 /* Called from selinux_complete_init, try to find a dentry. */
1204 dentry = d_find_alias(inode);
1205 }
1206 if (!dentry) {
744ba35e 1207 printk(KERN_WARNING "SELinux: %s: no dentry for dev=%s "
dd6f953a 1208 "ino=%ld\n", __func__, inode->i_sb->s_id,
1da177e4 1209 inode->i_ino);
23970741 1210 goto out_unlock;
1da177e4
LT		 1211 }
1212
1213 len = INITCONTEXTLEN;
869ab514 1214 context = kmalloc(len, GFP_NOFS);
1da177e4
LT		 1215 if (!context) {
1216 rc = -ENOMEM;
1217 dput(dentry);
23970741 1218 goto out_unlock;
1da177e4
LT		 1219 }
1220 rc = inode->i_op->getxattr(dentry, XATTR_NAME_SELINUX,
1221 context, len);
1222 if (rc == -ERANGE) {
1223 /* Need a larger buffer. Query for the right size. */
1224 rc = inode->i_op->getxattr(dentry, XATTR_NAME_SELINUX,
1225 NULL, 0);
1226 if (rc < 0) {
1227 dput(dentry);
23970741 1228 goto out_unlock;
1da177e4
LT		 1229 }
1230 kfree(context);
1231 len = rc;
869ab514 1232 context = kmalloc(len, GFP_NOFS);
1da177e4
LT		 1233 if (!context) {
1234 rc = -ENOMEM;
1235 dput(dentry);
23970741 1236 goto out_unlock;
1da177e4
LT		 1237 }
1238 rc = inode->i_op->getxattr(dentry,
1239 XATTR_NAME_SELINUX,
1240 context, len);
1241 }
1242 dput(dentry);
1243 if (rc < 0) {
1244 if (rc != -ENODATA) {
744ba35e 1245 printk(KERN_WARNING "SELinux: %s: getxattr returned "
dd6f953a 1246 "%d for dev=%s ino=%ld\n", __func__,
1da177e4
LT		 1247 -rc, inode->i_sb->s_id, inode->i_ino);
1248 kfree(context);
23970741 1249 goto out_unlock;
1da177e4
LT		 1250 }
1251 /* Map ENODATA to the default file SID */
1252 sid = sbsec->def_sid;
1253 rc = 0;
1254 } else {
f5c1d5b2 1255 rc = security_context_to_sid_default(context, rc, &sid,
869ab514
SS		 1256 sbsec->def_sid,
1257 GFP_NOFS);
1da177e4 1258 if (rc) {
744ba35e 1259 printk(KERN_WARNING "SELinux: %s: context_to_sid(%s) "
1da177e4 1260 "returned %d for dev=%s ino=%ld\n",
dd6f953a 1261 __func__, context, -rc,
1da177e4
LT		 1262 inode->i_sb->s_id, inode->i_ino);
1263 kfree(context);
1264 /* Leave with the unlabeled SID */
1265 rc = 0;
1266 break;
1267 }
1268 }
1269 kfree(context);
1270 isec->sid = sid;
1271 break;
1272 case SECURITY_FS_USE_TASK:
1273 isec->sid = isec->task_sid;
1274 break;
1275 case SECURITY_FS_USE_TRANS:
1276 /* Default to the fs SID. */
1277 isec->sid = sbsec->sid;
1278
1279 /* Try to obtain a transition SID. */
1280 isec->sclass = inode_mode_to_security_class(inode->i_mode);
1281 rc = security_transition_sid(isec->task_sid,
1282 sbsec->sid,
1283 isec->sclass,
1284 &sid);
1285 if (rc)
23970741 1286 goto out_unlock;
1da177e4
LT		 1287 isec->sid = sid;
1288 break;
c312feb2
EP		 1289 case SECURITY_FS_USE_MNTPOINT:
1290 isec->sid = sbsec->mntpoint_sid;
1291 break;
1da177e4 1292 default:
c312feb2 1293 /* Default to the fs superblock SID. */
1da177e4
LT		 1294 isec->sid = sbsec->sid;
1295
ea6b184f 1296 if (sbsec->proc && !S_ISLNK(inode->i_mode)) {
1da177e4
LT		 1297 struct proc_inode *proci = PROC_I(inode);
1298 if (proci->pde) {
1299 isec->sclass = inode_mode_to_security_class(inode->i_mode);
1300 rc = selinux_proc_get_sid(proci->pde,
1301 isec->sclass,
1302 &sid);
1303 if (rc)
23970741 1304 goto out_unlock;
1da177e4
LT		 1305 isec->sid = sid;
1306 }
1307 }
1308 break;
1309 }
1310
1311 isec->initialized = 1;
1312
23970741
EP		 1313out_unlock:
1314 mutex_unlock(&isec->lock);
1da177e4
LT		 1315out:
1316 if (isec->sclass == SECCLASS_FILE)
1317 isec->sclass = inode_mode_to_security_class(inode->i_mode);
1da177e4
LT		 1318 return rc;
1319}
1320
1321/* Convert a Linux signal to an access vector. */
1322static inline u32 signal_to_av(int sig)
1323{
1324 u32 perm = 0;
1325
1326 switch (sig) {
1327 case SIGCHLD:
1328 /* Commonly granted from child to parent. */
1329 perm = PROCESS__SIGCHLD;
1330 break;
1331 case SIGKILL:
1332 /* Cannot be caught or ignored */
1333 perm = PROCESS__SIGKILL;
1334 break;
1335 case SIGSTOP:
1336 /* Cannot be caught or ignored */
1337 perm = PROCESS__SIGSTOP;
1338 break;
1339 default:
1340 /* All other signals. */
1341 perm = PROCESS__SIGNAL;
1342 break;
1343 }
1344
1345 return perm;
1346}
1347
1348/* Check permission betweeen a pair of tasks, e.g. signal checks,
1349 fork check, ptrace check, etc. */
1350static int task_has_perm(struct task_struct *tsk1,
1351 struct task_struct *tsk2,
1352 u32 perms)
1353{
1354 struct task_security_struct *tsec1, *tsec2;
1355
1356 tsec1 = tsk1->security;
1357 tsec2 = tsk2->security;
1358 return avc_has_perm(tsec1->sid, tsec2->sid,
1359 SECCLASS_PROCESS, perms, NULL);
1360}
1361
b68e418c
SS		 1362#if CAP_LAST_CAP > 63
1363#error Fix SELinux to handle capabilities > 63.
1364#endif
1365
1da177e4
LT		 1366/* Check whether a task is allowed to use a capability. */
1367static int task_has_capability(struct task_struct *tsk,
1368 int cap)
1369{
1370 struct task_security_struct *tsec;
1371 struct avc_audit_data ad;
b68e418c
SS		 1372 u16 sclass;
1373 u32 av = CAP_TO_MASK(cap);
1da177e4
LT		 1374
1375 tsec = tsk->security;
1376
828dfe1d 1377 AVC_AUDIT_DATA_INIT(&ad, CAP);
1da177e4
LT		 1378 ad.tsk = tsk;
1379 ad.u.cap = cap;
1380
b68e418c
SS		 1381 switch (CAP_TO_INDEX(cap)) {
1382 case 0:
1383 sclass = SECCLASS_CAPABILITY;
1384 break;
1385 case 1:
1386 sclass = SECCLASS_CAPABILITY2;
1387 break;
1388 default:
1389 printk(KERN_ERR
1390 "SELinux: out of range capability %d\n", cap);
1391 BUG();
1392 }
1393 return avc_has_perm(tsec->sid, tsec->sid, sclass, av, &ad);
1da177e4
LT		 1394}
1395
1396/* Check whether a task is allowed to use a system operation. */
1397static int task_has_system(struct task_struct *tsk,
1398 u32 perms)
1399{
1400 struct task_security_struct *tsec;
1401
1402 tsec = tsk->security;
1403
1404 return avc_has_perm(tsec->sid, SECINITSID_KERNEL,
1405 SECCLASS_SYSTEM, perms, NULL);
1406}
1407
1408/* Check whether a task has a particular permission to an inode.
1409 The 'adp' parameter is optional and allows other audit
1410 data to be passed (e.g. the dentry). */
1411static int inode_has_perm(struct task_struct *tsk,
1412 struct inode *inode,
1413 u32 perms,
1414 struct avc_audit_data *adp)
1415{
1416 struct task_security_struct *tsec;
1417 struct inode_security_struct *isec;
1418 struct avc_audit_data ad;
1419
828dfe1d 1420 if (unlikely(IS_PRIVATE(inode)))
bbaca6c2
SS		 1421 return 0;
1422
1da177e4
LT		 1423 tsec = tsk->security;
1424 isec = inode->i_security;
1425
1426 if (!adp) {
1427 adp = &ad;
1428 AVC_AUDIT_DATA_INIT(&ad, FS);
1429 ad.u.fs.inode = inode;
1430 }
1431
1432 return avc_has_perm(tsec->sid, isec->sid, isec->sclass, perms, adp);
1433}
1434
1435/* Same as inode_has_perm, but pass explicit audit data containing
1436 the dentry to help the auditing code to more easily generate the
1437 pathname if needed. */
1438static inline int dentry_has_perm(struct task_struct *tsk,
1439 struct vfsmount *mnt,
1440 struct dentry *dentry,
1441 u32 av)
1442{
1443 struct inode *inode = dentry->d_inode;
1444 struct avc_audit_data ad;
828dfe1d 1445 AVC_AUDIT_DATA_INIT(&ad, FS);
44707fdf
JB		 1446 ad.u.fs.path.mnt = mnt;
1447 ad.u.fs.path.dentry = dentry;
1da177e4
LT		 1448 return inode_has_perm(tsk, inode, av, &ad);
1449}
1450
1451/* Check whether a task can use an open file descriptor to
1452 access an inode in a given way. Check access to the
1453 descriptor itself, and then use dentry_has_perm to
1454 check a particular permission to the file.
1455 Access to the descriptor is implicitly granted if it
1456 has the same SID as the process. If av is zero, then
1457 access to the file is not checked, e.g. for cases
1458 where only the descriptor is affected like seek. */
858119e1 1459static int file_has_perm(struct task_struct *tsk,
1da177e4
LT		 1460 struct file *file,
1461 u32 av)
1462{
1463 struct task_security_struct *tsec = tsk->security;
1464 struct file_security_struct *fsec = file->f_security;
44707fdf 1465 struct inode *inode = file->f_path.dentry->d_inode;
1da177e4
LT		 1466 struct avc_audit_data ad;
1467 int rc;
1468
1469 AVC_AUDIT_DATA_INIT(&ad, FS);
44707fdf 1470 ad.u.fs.path = file->f_path;
1da177e4
LT		 1471
1472 if (tsec->sid != fsec->sid) {
1473 rc = avc_has_perm(tsec->sid, fsec->sid,
1474 SECCLASS_FD,
1475 FD__USE,
1476 &ad);
1477 if (rc)
1478 return rc;
1479 }
1480
1481 /* av is zero if only checking access to the descriptor. */
1482 if (av)
1483 return inode_has_perm(tsk, inode, av, &ad);
1484
1485 return 0;
1486}
1487
1488/* Check whether a task can create a file. */
1489static int may_create(struct inode *dir,
1490 struct dentry *dentry,
1491 u16 tclass)
1492{
1493 struct task_security_struct *tsec;
1494 struct inode_security_struct *dsec;
1495 struct superblock_security_struct *sbsec;
1496 u32 newsid;
1497 struct avc_audit_data ad;
1498 int rc;
1499
1500 tsec = current->security;
1501 dsec = dir->i_security;
1502 sbsec = dir->i_sb->s_security;
1503
1504 AVC_AUDIT_DATA_INIT(&ad, FS);
44707fdf 1505 ad.u.fs.path.dentry = dentry;
1da177e4
LT		 1506
1507 rc = avc_has_perm(tsec->sid, dsec->sid, SECCLASS_DIR,
1508 DIR__ADD_NAME | DIR__SEARCH,
1509 &ad);
1510 if (rc)
1511 return rc;
1512
1513 if (tsec->create_sid && sbsec->behavior != SECURITY_FS_USE_MNTPOINT) {
1514 newsid = tsec->create_sid;
1515 } else {
1516 rc = security_transition_sid(tsec->sid, dsec->sid, tclass,
1517 &newsid);
1518 if (rc)
1519 return rc;
1520 }
1521
1522 rc = avc_has_perm(tsec->sid, newsid, tclass, FILE__CREATE, &ad);
1523 if (rc)
1524 return rc;
1525
1526 return avc_has_perm(newsid, sbsec->sid,
1527 SECCLASS_FILESYSTEM,
1528 FILESYSTEM__ASSOCIATE, &ad);
1529}
1530
4eb582cf
ML		 1531/* Check whether a task can create a key. */
1532static int may_create_key(u32 ksid,
1533 struct task_struct *ctx)
1534{
1535 struct task_security_struct *tsec;
1536
1537 tsec = ctx->security;
1538
1539 return avc_has_perm(tsec->sid, ksid, SECCLASS_KEY, KEY__CREATE, NULL);
1540}
1541
828dfe1d
EP		 1542#define MAY_LINK 0
1543#define MAY_UNLINK 1
1544#define MAY_RMDIR 2
1da177e4
LT		 1545
1546/* Check whether a task can link, unlink, or rmdir a file/directory. */
1547static int may_link(struct inode *dir,
1548 struct dentry *dentry,
1549 int kind)
1550
1551{
1552 struct task_security_struct *tsec;
1553 struct inode_security_struct *dsec, *isec;
1554 struct avc_audit_data ad;
1555 u32 av;
1556 int rc;
1557
1558 tsec = current->security;
1559 dsec = dir->i_security;
1560 isec = dentry->d_inode->i_security;
1561
1562 AVC_AUDIT_DATA_INIT(&ad, FS);
44707fdf 1563 ad.u.fs.path.dentry = dentry;
1da177e4
LT		 1564
1565 av = DIR__SEARCH;
1566 av |= (kind ? DIR__REMOVE_NAME : DIR__ADD_NAME);
1567 rc = avc_has_perm(tsec->sid, dsec->sid, SECCLASS_DIR, av, &ad);
1568 if (rc)
1569 return rc;
1570
1571 switch (kind) {
1572 case MAY_LINK:
1573 av = FILE__LINK;
1574 break;
1575 case MAY_UNLINK:
1576 av = FILE__UNLINK;
1577 break;
1578 case MAY_RMDIR:
1579 av = DIR__RMDIR;
1580 break;
1581 default:
744ba35e
EP		 1582 printk(KERN_WARNING "SELinux: %s: unrecognized kind %d\n",
1583 __func__, kind);
1da177e4
LT		 1584 return 0;
1585 }
1586
1587 rc = avc_has_perm(tsec->sid, isec->sid, isec->sclass, av, &ad);
1588 return rc;
1589}
1590
1591static inline int may_rename(struct inode *old_dir,
1592 struct dentry *old_dentry,
1593 struct inode *new_dir,
1594 struct dentry *new_dentry)
1595{
1596 struct task_security_struct *tsec;
1597 struct inode_security_struct *old_dsec, *new_dsec, *old_isec, *new_isec;
1598 struct avc_audit_data ad;
1599 u32 av;
1600 int old_is_dir, new_is_dir;
1601 int rc;
1602
1603 tsec = current->security;
1604 old_dsec = old_dir->i_security;
1605 old_isec = old_dentry->d_inode->i_security;
1606 old_is_dir = S_ISDIR(old_dentry->d_inode->i_mode);
1607 new_dsec = new_dir->i_security;
1608
1609 AVC_AUDIT_DATA_INIT(&ad, FS);
1610
44707fdf 1611 ad.u.fs.path.dentry = old_dentry;
1da177e4
LT		 1612 rc = avc_has_perm(tsec->sid, old_dsec->sid, SECCLASS_DIR,
1613 DIR__REMOVE_NAME | DIR__SEARCH, &ad);
1614 if (rc)
1615 return rc;
1616 rc = avc_has_perm(tsec->sid, old_isec->sid,
1617 old_isec->sclass, FILE__RENAME, &ad);
1618 if (rc)
1619 return rc;
1620 if (old_is_dir && new_dir != old_dir) {
1621 rc = avc_has_perm(tsec->sid, old_isec->sid,
1622 old_isec->sclass, DIR__REPARENT, &ad);
1623 if (rc)
1624 return rc;
1625 }
1626
44707fdf 1627 ad.u.fs.path.dentry = new_dentry;
1da177e4
LT		 1628 av = DIR__ADD_NAME | DIR__SEARCH;
1629 if (new_dentry->d_inode)
1630 av |= DIR__REMOVE_NAME;
1631 rc = avc_has_perm(tsec->sid, new_dsec->sid, SECCLASS_DIR, av, &ad);
1632 if (rc)
1633 return rc;
1634 if (new_dentry->d_inode) {
1635 new_isec = new_dentry->d_inode->i_security;
1636 new_is_dir = S_ISDIR(new_dentry->d_inode->i_mode);
1637 rc = avc_has_perm(tsec->sid, new_isec->sid,
1638 new_isec->sclass,
1639 (new_is_dir ? DIR__RMDIR : FILE__UNLINK), &ad);
1640 if (rc)
1641 return rc;
1642 }
1643
1644 return 0;
1645}
1646
1647/* Check whether a task can perform a filesystem operation. */
1648static int superblock_has_perm(struct task_struct *tsk,
1649 struct super_block *sb,
1650 u32 perms,
1651 struct avc_audit_data *ad)
1652{
1653 struct task_security_struct *tsec;
1654 struct superblock_security_struct *sbsec;
1655
1656 tsec = tsk->security;
1657 sbsec = sb->s_security;
1658 return avc_has_perm(tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM,
1659 perms, ad);
1660}
1661
1662/* Convert a Linux mode and permission mask to an access vector. */
1663static inline u32 file_mask_to_av(int mode, int mask)
1664{
1665 u32 av = 0;
1666
1667 if ((mode & S_IFMT) != S_IFDIR) {
1668 if (mask & MAY_EXEC)
1669 av |= FILE__EXECUTE;
1670 if (mask & MAY_READ)
1671 av |= FILE__READ;
1672
1673 if (mask & MAY_APPEND)
1674 av |= FILE__APPEND;
1675 else if (mask & MAY_WRITE)
1676 av |= FILE__WRITE;
1677
1678 } else {
1679 if (mask & MAY_EXEC)
1680 av |= DIR__SEARCH;
1681 if (mask & MAY_WRITE)
1682 av |= DIR__WRITE;
1683 if (mask & MAY_READ)
1684 av |= DIR__READ;
1685 }
1686
1687 return av;
1688}
1689
8b6a5a37
EP		 1690/* Convert a Linux file to an access vector. */
1691static inline u32 file_to_av(struct file *file)
1692{
1693 u32 av = 0;
1694
1695 if (file->f_mode & FMODE_READ)
1696 av |= FILE__READ;
1697 if (file->f_mode & FMODE_WRITE) {
1698 if (file->f_flags & O_APPEND)
1699 av |= FILE__APPEND;
1700 else
1701 av |= FILE__WRITE;
1702 }
1703 if (!av) {
1704 /*
1705 * Special file opened with flags 3 for ioctl-only use.
1706 */
1707 av = FILE__IOCTL;
1708 }
1709
1710 return av;
1711}
1712
b0c636b9 1713/*
8b6a5a37 1714 * Convert a file to an access vector and include the correct open
b0c636b9
EP		 1715 * open permission.
1716 */
8b6a5a37 1717static inline u32 open_file_to_av(struct file *file)
b0c636b9 1718{
8b6a5a37 1719 u32 av = file_to_av(file);
b0c636b9
EP		 1720
1721 if (selinux_policycap_openperm) {
8b6a5a37 1722 mode_t mode = file->f_path.dentry->d_inode->i_mode;
b0c636b9
EP		 1723 /*
1724 * lnk files and socks do not really have an 'open'
1725 */
1726 if (S_ISREG(mode))
1727 av |= FILE__OPEN;
1728 else if (S_ISCHR(mode))
1729 av |= CHR_FILE__OPEN;
1730 else if (S_ISBLK(mode))
1731 av |= BLK_FILE__OPEN;
1732 else if (S_ISFIFO(mode))
1733 av |= FIFO_FILE__OPEN;
1734 else if (S_ISDIR(mode))
1735 av |= DIR__OPEN;
1736 else
744ba35e 1737 printk(KERN_ERR "SELinux: WARNING: inside %s with "
8b6a5a37 1738 "unknown mode:%o\n", __func__, mode);
b0c636b9
EP		 1739 }
1740 return av;
1741}
1742
1da177e4
LT		 1743/* Hook functions begin here. */
1744
5cd9c58f
DH		 1745static int selinux_ptrace_may_access(struct task_struct *child,
1746 unsigned int mode)
1da177e4 1747{
1da177e4
LT		 1748 int rc;
1749
5cd9c58f 1750 rc = secondary_ops->ptrace_may_access(child, mode);
1da177e4
LT		 1751 if (rc)
1752 return rc;
1753
006ebb40 1754 if (mode == PTRACE_MODE_READ) {
5cd9c58f 1755 struct task_security_struct *tsec = current->security;
006ebb40
SS		 1756 struct task_security_struct *csec = child->security;
1757 return avc_has_perm(tsec->sid, csec->sid,
1758 SECCLASS_FILE, FILE__READ, NULL);
1759 }
1760
5cd9c58f
DH		 1761 return task_has_perm(current, child, PROCESS__PTRACE);
1762}
1763
1764static int selinux_ptrace_traceme(struct task_struct *parent)
1765{
1766 int rc;
1767
1768 rc = secondary_ops->ptrace_traceme(parent);
1769 if (rc)
1770 return rc;
1771
1772 return task_has_perm(parent, current, PROCESS__PTRACE);
1da177e4
LT		 1773}
1774
1775static int selinux_capget(struct task_struct *target, kernel_cap_t *effective,
828dfe1d 1776 kernel_cap_t *inheritable, kernel_cap_t *permitted)
1da177e4
LT		 1777{
1778 int error;
1779
1780 error = task_has_perm(current, target, PROCESS__GETCAP);
1781 if (error)
1782 return error;
1783
1784 return secondary_ops->capget(target, effective, inheritable, permitted);
1785}
1786
1787static int selinux_capset_check(struct task_struct *target, kernel_cap_t *effective,
828dfe1d 1788 kernel_cap_t *inheritable, kernel_cap_t *permitted)
1da177e4
LT		 1789{
1790 int error;
1791
1792 error = secondary_ops->capset_check(target, effective, inheritable, permitted);
1793 if (error)
1794 return error;
1795
1796 return task_has_perm(current, target, PROCESS__SETCAP);
1797}
1798
1799static void selinux_capset_set(struct task_struct *target, kernel_cap_t *effective,
828dfe1d 1800 kernel_cap_t *inheritable, kernel_cap_t *permitted)
1da177e4
LT		 1801{
1802 secondary_ops->capset_set(target, effective, inheritable, permitted);
1803}
1804
1805static int selinux_capable(struct task_struct *tsk, int cap)
1806{
1807 int rc;
1808
1809 rc = secondary_ops->capable(tsk, cap);
1810 if (rc)
1811 return rc;
1812
828dfe1d 1813 return task_has_capability(tsk, cap);
1da177e4
LT		 1814}
1815
3fbfa981
EB		 1816static int selinux_sysctl_get_sid(ctl_table *table, u16 tclass, u32 *sid)
1817{
1818 int buflen, rc;
1819 char *buffer, *path, *end;
1820
1821 rc = -ENOMEM;
828dfe1d 1822 buffer = (char *)__get_free_page(GFP_KERNEL);
3fbfa981
EB		 1823 if (!buffer)
1824 goto out;
1825
1826 buflen = PAGE_SIZE;
1827 end = buffer+buflen;
1828 *--end = '\0';
1829 buflen--;
1830 path = end-1;
1831 *path = '/';
1832 while (table) {
1833 const char *name = table->procname;
1834 size_t namelen = strlen(name);
1835 buflen -= namelen + 1;
1836 if (buflen < 0)
1837 goto out_free;
1838 end -= namelen;
1839 memcpy(end, name, namelen);
1840 *--end = '/';
1841 path = end;
1842 table = table->parent;
1843 }
b599fdfd
EB		 1844 buflen -= 4;
1845 if (buflen < 0)
1846 goto out_free;
1847 end -= 4;
1848 memcpy(end, "/sys", 4);
1849 path = end;
3fbfa981
EB		 1850 rc = security_genfs_sid("proc", path, tclass, sid);
1851out_free:
1852 free_page((unsigned long)buffer);
1853out:
1854 return rc;
1855}
1856
1da177e4
LT		 1857static int selinux_sysctl(ctl_table *table, int op)
1858{
1859 int error = 0;
1860 u32 av;
1861 struct task_security_struct *tsec;
1862 u32 tsid;
1863 int rc;
1864
1865 rc = secondary_ops->sysctl(table, op);
1866 if (rc)
1867 return rc;
1868
1869 tsec = current->security;
1870
3fbfa981
EB		 1871 rc = selinux_sysctl_get_sid(table, (op == 0001) ?
1872 SECCLASS_DIR : SECCLASS_FILE, &tsid);
1da177e4
LT		 1873 if (rc) {
1874 /* Default to the well-defined sysctl SID. */
1875 tsid = SECINITSID_SYSCTL;
1876 }
1877
1878 /* The op values are "defined" in sysctl.c, thereby creating
1879 * a bad coupling between this module and sysctl.c */
828dfe1d 1880 if (op == 001) {
1da177e4
LT		 1881 error = avc_has_perm(tsec->sid, tsid,
1882 SECCLASS_DIR, DIR__SEARCH, NULL);
1883 } else {
1884 av = 0;
1885 if (op & 004)
1886 av |= FILE__READ;
1887 if (op & 002)
1888 av |= FILE__WRITE;
1889 if (av)
1890 error = avc_has_perm(tsec->sid, tsid,
1891 SECCLASS_FILE, av, NULL);
828dfe1d 1892 }
1da177e4
LT		 1893
1894 return error;
1895}
1896
1897static int selinux_quotactl(int cmds, int type, int id, struct super_block *sb)
1898{
1899 int rc = 0;
1900
1901 if (!sb)
1902 return 0;
1903
1904 switch (cmds) {
828dfe1d
EP		 1905 case Q_SYNC:
1906 case Q_QUOTAON:
1907 case Q_QUOTAOFF:
1908 case Q_SETINFO:
1909 case Q_SETQUOTA:
1910 rc = superblock_has_perm(current, sb, FILESYSTEM__QUOTAMOD,
1911 NULL);
1912 break;
1913 case Q_GETFMT:
1914 case Q_GETINFO:
1915 case Q_GETQUOTA:
1916 rc = superblock_has_perm(current, sb, FILESYSTEM__QUOTAGET,
1917 NULL);
1918 break;
1919 default:
1920 rc = 0; /* let the kernel handle invalid cmds */
1921 break;
1da177e4
LT		 1922 }
1923 return rc;
1924}
1925
1926static int selinux_quota_on(struct dentry *dentry)
1927{
1928 return dentry_has_perm(current, NULL, dentry, FILE__QUOTAON);
1929}
1930
1931static int selinux_syslog(int type)
1932{
1933 int rc;
1934
1935 rc = secondary_ops->syslog(type);
1936 if (rc)
1937 return rc;
1938
1939 switch (type) {
828dfe1d
EP		 1940 case 3: /* Read last kernel messages */
1941 case 10: /* Return size of the log buffer */
1942 rc = task_has_system(current, SYSTEM__SYSLOG_READ);
1943 break;
1944 case 6: /* Disable logging to console */
1945 case 7: /* Enable logging to console */
1946 case 8: /* Set level of messages printed to console */
1947 rc = task_has_system(current, SYSTEM__SYSLOG_CONSOLE);
1948 break;
1949 case 0: /* Close log */
1950 case 1: /* Open log */
1951 case 2: /* Read from log */
1952 case 4: /* Read/clear last kernel messages */
1953 case 5: /* Clear ring buffer */
1954 default:
1955 rc = task_has_system(current, SYSTEM__SYSLOG_MOD);
1956 break;
1da177e4
LT		 1957 }
1958 return rc;
1959}
1960
1961/*
1962 * Check that a process has enough memory to allocate a new virtual
1963 * mapping. 0 means there is enough memory for the allocation to
1964 * succeed and -ENOMEM implies there is not.
1965 *
1966 * Note that secondary_ops->capable and task_has_perm_noaudit return 0
1967 * if the capability is granted, but __vm_enough_memory requires 1 if
1968 * the capability is granted.
1969 *
1970 * Do not audit the selinux permission check, as this is applied to all
1971 * processes that allocate mappings.
1972 */
34b4e4aa 1973static int selinux_vm_enough_memory(struct mm_struct *mm, long pages)
1da177e4
LT		 1974{
1975 int rc, cap_sys_admin = 0;
1976 struct task_security_struct *tsec = current->security;
1977
1978 rc = secondary_ops->capable(current, CAP_SYS_ADMIN);
1979 if (rc == 0)
1980 rc = avc_has_perm_noaudit(tsec->sid, tsec->sid,
2c3c05db
SS		 1981 SECCLASS_CAPABILITY,
1982 CAP_TO_MASK(CAP_SYS_ADMIN),
1983 0,
1984 NULL);
1da177e4
LT		 1985
1986 if (rc == 0)
1987 cap_sys_admin = 1;
1988
34b4e4aa 1989 return __vm_enough_memory(mm, pages, cap_sys_admin);
1da177e4
LT		 1990}
1991
1992/* binprm security operations */
1993
1994static int selinux_bprm_alloc_security(struct linux_binprm *bprm)
1995{
1996 struct bprm_security_struct *bsec;
1997
89d155ef 1998 bsec = kzalloc(sizeof(struct bprm_security_struct), GFP_KERNEL);
1da177e4
LT		 1999 if (!bsec)
2000 return -ENOMEM;
2001
1da177e4
LT		 2002 bsec->sid = SECINITSID_UNLABELED;
2003 bsec->set = 0;
2004
2005 bprm->security = bsec;
2006 return 0;
2007}
2008
2009static int selinux_bprm_set_security(struct linux_binprm *bprm)
2010{
2011 struct task_security_struct *tsec;
3d5ff529 2012 struct inode *inode = bprm->file->f_path.dentry->d_inode;
1da177e4
LT		 2013 struct inode_security_struct *isec;
2014 struct bprm_security_struct *bsec;
2015 u32 newsid;
2016 struct avc_audit_data ad;
2017 int rc;
2018
2019 rc = secondary_ops->bprm_set_security(bprm);
2020 if (rc)
2021 return rc;
2022
2023 bsec = bprm->security;
2024
2025 if (bsec->set)
2026 return 0;
2027
2028 tsec = current->security;
2029 isec = inode->i_security;
2030
2031 /* Default to the current task SID. */
2032 bsec->sid = tsec->sid;
2033
28eba5bf 2034 /* Reset fs, key, and sock SIDs on execve. */
1da177e4 2035 tsec->create_sid = 0;
28eba5bf 2036 tsec->keycreate_sid = 0;
42c3e03e 2037 tsec->sockcreate_sid = 0;
1da177e4
LT		 2038
2039 if (tsec->exec_sid) {
2040 newsid = tsec->exec_sid;
2041 /* Reset exec SID on execve. */
2042 tsec->exec_sid = 0;
2043 } else {
2044 /* Check for a default transition on this program. */
2045 rc = security_transition_sid(tsec->sid, isec->sid,
828dfe1d 2046 SECCLASS_PROCESS, &newsid);
1da177e4
LT		 2047 if (rc)
2048 return rc;
2049 }
2050
2051 AVC_AUDIT_DATA_INIT(&ad, FS);
44707fdf 2052 ad.u.fs.path = bprm->file->f_path;
1da177e4 2053
3d5ff529 2054 if (bprm->file->f_path.mnt->mnt_flags & MNT_NOSUID)
1da177e4
LT		 2055 newsid = tsec->sid;
2056
828dfe1d 2057 if (tsec->sid == newsid) {
1da177e4
LT		 2058 rc = avc_has_perm(tsec->sid, isec->sid,
2059 SECCLASS_FILE, FILE__EXECUTE_NO_TRANS, &ad);
2060 if (rc)
2061 return rc;
2062 } else {
2063 /* Check permissions for the transition. */
2064 rc = avc_has_perm(tsec->sid, newsid,
2065 SECCLASS_PROCESS, PROCESS__TRANSITION, &ad);
2066 if (rc)
2067 return rc;
2068
2069 rc = avc_has_perm(newsid, isec->sid,
2070 SECCLASS_FILE, FILE__ENTRYPOINT, &ad);
2071 if (rc)
2072 return rc;
2073
2074 /* Clear any possibly unsafe personality bits on exec: */
2075 current->personality &= ~PER_CLEAR_ON_SETID;
2076
2077 /* Set the security field to the new SID. */
2078 bsec->sid = newsid;
2079 }
2080
2081 bsec->set = 1;
2082 return 0;
2083}
2084
828dfe1d 2085static int selinux_bprm_check_security(struct linux_binprm *bprm)
1da177e4
LT		 2086{
2087 return secondary_ops->bprm_check_security(bprm);
2088}
2089
2090
828dfe1d 2091static int selinux_bprm_secureexec(struct linux_binprm *bprm)
1da177e4
LT		 2092{
2093 struct task_security_struct *tsec = current->security;
2094 int atsecure = 0;
2095
2096 if (tsec->osid != tsec->sid) {
2097 /* Enable secure mode for SIDs transitions unless
2098 the noatsecure permission is granted between
2099 the two SIDs, i.e. ahp returns 0. */
2100 atsecure = avc_has_perm(tsec->osid, tsec->sid,
2101 SECCLASS_PROCESS,
2102 PROCESS__NOATSECURE, NULL);
2103 }
2104
2105 return (atsecure || secondary_ops->bprm_secureexec(bprm));
2106}
2107
2108static void selinux_bprm_free_security(struct linux_binprm *bprm)
2109{
9a5f04bf 2110 kfree(bprm->security);
1da177e4 2111 bprm->security = NULL;
1da177e4
LT		 2112}
2113
2114extern struct vfsmount *selinuxfs_mount;
2115extern struct dentry *selinux_null;
2116
2117/* Derived from fs/exec.c:flush_old_files. */
828dfe1d 2118static inline void flush_unauthorized_files(struct files_struct *files)
1da177e4
LT		 2119{
2120 struct avc_audit_data ad;
2121 struct file *file, *devnull = NULL;
b20c8122 2122 struct tty_struct *tty;
badf1662 2123 struct fdtable *fdt;
1da177e4 2124 long j = -1;
24ec839c 2125 int drop_tty = 0;
1da177e4 2126
24ec839c 2127 tty = get_current_tty();
1da177e4
LT		 2128 if (tty) {
2129 file_list_lock();
37dd0bd0
EP		 2130 if (!list_empty(&tty->tty_files)) {
2131 struct inode *inode;
2132
1da177e4
LT		 2133 /* Revalidate access to controlling tty.
2134 Use inode_has_perm on the tty inode directly rather
2135 than using file_has_perm, as this particular open
2136 file may belong to another process and we are only
2137 interested in the inode-based check here. */
37dd0bd0
EP		 2138 file = list_first_entry(&tty->tty_files, struct file, f_u.fu_list);
2139 inode = file->f_path.dentry->d_inode;
1da177e4
LT		 2140 if (inode_has_perm(current, inode,
2141 FILE__READ | FILE__WRITE, NULL)) {
24ec839c 2142 drop_tty = 1;
1da177e4
LT		 2143 }
2144 }
2145 file_list_unlock();
452a00d2 2146 tty_kref_put(tty);
1da177e4 2147 }
98a27ba4
EB		 2148 /* Reset controlling tty. */
2149 if (drop_tty)
2150 no_tty();
1da177e4
LT		 2151
2152 /* Revalidate access to inherited open files. */
2153
828dfe1d 2154 AVC_AUDIT_DATA_INIT(&ad, FS);
1da177e4
LT		 2155
2156 spin_lock(&files->file_lock);
2157 for (;;) {
2158 unsigned long set, i;
2159 int fd;
2160
2161 j++;
2162 i = j * __NFDBITS;
badf1662 2163 fdt = files_fdtable(files);
bbea9f69 2164 if (i >= fdt->max_fds)
1da177e4 2165 break;
badf1662 2166 set = fdt->open_fds->fds_bits[j];
1da177e4
LT		 2167 if (!set)
2168 continue;
2169 spin_unlock(&files->file_lock);
828dfe1d 2170 for ( ; set ; i++, set >>= 1) {
1da177e4
LT		 2171 if (set & 1) {
2172 file = fget(i);
2173 if (!file)
2174 continue;
2175 if (file_has_perm(current,
2176 file,
2177 file_to_av(file))) {
2178 sys_close(i);
2179 fd = get_unused_fd();
2180 if (fd != i) {
2181 if (fd >= 0)
2182 put_unused_fd(fd);
2183 fput(file);
2184 continue;
2185 }
2186 if (devnull) {
095975da 2187 get_file(devnull);
1da177e4
LT		 2188 } else {
2189 devnull = dentry_open(dget(selinux_null), mntget(selinuxfs_mount), O_RDWR);
fc5d81e6
AM		 2190 if (IS_ERR(devnull)) {
2191 devnull = NULL;
1da177e4
LT		 2192 put_unused_fd(fd);
2193 fput(file);
2194 continue;
2195 }
2196 }
2197 fd_install(fd, devnull);
2198 }
2199 fput(file);
2200 }
2201 }
2202 spin_lock(&files->file_lock);
2203
2204 }
2205 spin_unlock(&files->file_lock);
2206}
2207
2208static void selinux_bprm_apply_creds(struct linux_binprm *bprm, int unsafe)
2209{
2210 struct task_security_struct *tsec;
2211 struct bprm_security_struct *bsec;
2212 u32 sid;
2213 int rc;
2214
2215 secondary_ops->bprm_apply_creds(bprm, unsafe);
2216
2217 tsec = current->security;
2218
2219 bsec = bprm->security;
2220 sid = bsec->sid;
2221
2222 tsec->osid = tsec->sid;
2223 bsec->unsafe = 0;
2224 if (tsec->sid != sid) {
2225 /* Check for shared state. If not ok, leave SID
2226 unchanged and kill. */
2227 if (unsafe & LSM_UNSAFE_SHARE) {
2228 rc = avc_has_perm(tsec->sid, sid, SECCLASS_PROCESS,
2229 PROCESS__SHARE, NULL);
2230 if (rc) {
2231 bsec->unsafe = 1;
2232 return;
2233 }
2234 }
2235
2236 /* Check for ptracing, and update the task SID if ok.
2237 Otherwise, leave SID unchanged and kill. */
2238 if (unsafe & (LSM_UNSAFE_PTRACE | LSM_UNSAFE_PTRACE_CAP)) {
0356357c
RM		 2239 struct task_struct *tracer;
2240 struct task_security_struct *sec;
2241 u32 ptsid = 0;
2242
2243 rcu_read_lock();
0d094efe 2244 tracer = tracehook_tracer_task(current);
0356357c
RM		 2245 if (likely(tracer != NULL)) {
2246 sec = tracer->security;
2247 ptsid = sec->sid;
2248 }
2249 rcu_read_unlock();
2250
2251 if (ptsid != 0) {
2252 rc = avc_has_perm(ptsid, sid, SECCLASS_PROCESS,
2253 PROCESS__PTRACE, NULL);
2254 if (rc) {
2255 bsec->unsafe = 1;
2256 return;
2257 }
1da177e4
LT		 2258 }
2259 }
2260 tsec->sid = sid;
2261 }
2262}
2263
2264/*
2265 * called after apply_creds without the task lock held
2266 */
2267static void selinux_bprm_post_apply_creds(struct linux_binprm *bprm)
2268{
2269 struct task_security_struct *tsec;
2270 struct rlimit *rlim, *initrlim;
2271 struct itimerval itimer;
2272 struct bprm_security_struct *bsec;
41d9f9c5 2273 struct sighand_struct *psig;
1da177e4 2274 int rc, i;
41d9f9c5 2275 unsigned long flags;
1da177e4
LT		 2276
2277 tsec = current->security;
2278 bsec = bprm->security;
2279
2280 if (bsec->unsafe) {
2281 force_sig_specific(SIGKILL, current);
2282 return;
2283 }
2284 if (tsec->osid == tsec->sid)
2285 return;
2286
2287 /* Close files for which the new task SID is not authorized. */
2288 flush_unauthorized_files(current->files);
2289
2290 /* Check whether the new SID can inherit signal state
2291 from the old SID. If not, clear itimers to avoid
2292 subsequent signal generation and flush and unblock
2293 signals. This must occur _after_ the task SID has
2294 been updated so that any kill done after the flush
2295 will be checked against the new SID. */
2296 rc = avc_has_perm(tsec->osid, tsec->sid, SECCLASS_PROCESS,
2297 PROCESS__SIGINH, NULL);
2298 if (rc) {
2299 memset(&itimer, 0, sizeof itimer);
2300 for (i = 0; i < 3; i++)
2301 do_setitimer(i, &itimer, NULL);
2302 flush_signals(current);
2303 spin_lock_irq(&current->sighand->siglock);
2304 flush_signal_handlers(current, 1);
2305 sigemptyset(&current->blocked);
2306 recalc_sigpending();
2307 spin_unlock_irq(&current->sighand->siglock);
2308 }
2309
4ac212ad
SS		 2310 /* Always clear parent death signal on SID transitions. */
2311 current->pdeath_signal = 0;
2312
1da177e4
LT		 2313 /* Check whether the new SID can inherit resource limits
2314 from the old SID. If not, reset all soft limits to
2315 the lower of the current task's hard limit and the init
2316 task's soft limit. Note that the setting of hard limits
2317 (even to lower them) can be controlled by the setrlimit
2318 check. The inclusion of the init task's soft limit into
2319 the computation is to avoid resetting soft limits higher
2320 than the default soft limit for cases where the default
2321 is lower than the hard limit, e.g. RLIMIT_CORE or
2322 RLIMIT_STACK.*/
2323 rc = avc_has_perm(tsec->osid, tsec->sid, SECCLASS_PROCESS,
2324 PROCESS__RLIMITINH, NULL);
2325 if (rc) {
2326 for (i = 0; i < RLIM_NLIMITS; i++) {
2327 rlim = current->signal->rlim + i;
2328 initrlim = init_task.signal->rlim+i;
828dfe1d 2329 rlim->rlim_cur = min(rlim->rlim_max, initrlim->rlim_cur);
1da177e4 2330 }
f06febc9 2331 update_rlimit_cpu(rlim->rlim_cur);
1da177e4
LT		 2332 }
2333
2334 /* Wake up the parent if it is waiting so that it can
2335 recheck wait permission to the new task SID. */
41d9f9c5
EP		 2336 read_lock_irq(&tasklist_lock);
2337 psig = current->parent->sighand;
2338 spin_lock_irqsave(&psig->siglock, flags);
1da177e4 2339 wake_up_interruptible(&current->parent->signal->wait_chldexit);
41d9f9c5
EP		 2340 spin_unlock_irqrestore(&psig->siglock, flags);
2341 read_unlock_irq(&tasklist_lock);
1da177e4
LT		 2342}
2343
2344/* superblock security operations */
2345
2346static int selinux_sb_alloc_security(struct super_block *sb)
2347{
2348 return superblock_alloc_security(sb);
2349}
2350
2351static void selinux_sb_free_security(struct super_block *sb)
2352{
2353 superblock_free_security(sb);
2354}
2355
2356static inline int match_prefix(char *prefix, int plen, char *option, int olen)
2357{
2358 if (plen > olen)
2359 return 0;
2360
2361 return !memcmp(prefix, option, plen);
2362}
2363
2364static inline int selinux_option(char *option, int len)
2365{
832cbd9a
EP		 2366 return (match_prefix(CONTEXT_STR, sizeof(CONTEXT_STR)-1, option, len) ||
2367 match_prefix(FSCONTEXT_STR, sizeof(FSCONTEXT_STR)-1, option, len) ||
2368 match_prefix(DEFCONTEXT_STR, sizeof(DEFCONTEXT_STR)-1, option, len) ||
2369 match_prefix(ROOTCONTEXT_STR, sizeof(ROOTCONTEXT_STR)-1, option, len));
1da177e4
LT		 2370}
2371
2372static inline void take_option(char **to, char *from, int *first, int len)
2373{
2374 if (!*first) {
2375 **to = ',';
2376 *to += 1;
3528a953 2377 } else
1da177e4
LT		 2378 *first = 0;
2379 memcpy(*to, from, len);
2380 *to += len;
2381}
2382
828dfe1d
EP		 2383static inline void take_selinux_option(char **to, char *from, int *first,
2384 int len)
3528a953
CO		 2385{
2386 int current_size = 0;
2387
2388 if (!*first) {
2389 **to = '|';
2390 *to += 1;
828dfe1d 2391 } else
3528a953
CO		 2392 *first = 0;
2393
2394 while (current_size < len) {
2395 if (*from != '"') {
2396 **to = *from;
2397 *to += 1;
2398 }
2399 from += 1;
2400 current_size += 1;
2401 }
2402}
2403
e0007529 2404static int selinux_sb_copy_data(char *orig, char *copy)
1da177e4
LT		 2405{
2406 int fnosec, fsec, rc = 0;
2407 char *in_save, *in_curr, *in_end;
2408 char *sec_curr, *nosec_save, *nosec;
3528a953 2409 int open_quote = 0;
1da177e4
LT		 2410
2411 in_curr = orig;
2412 sec_curr = copy;
2413
1da177e4
LT		 2414 nosec = (char *)get_zeroed_page(GFP_KERNEL);
2415 if (!nosec) {
2416 rc = -ENOMEM;
2417 goto out;
2418 }
2419
2420 nosec_save = nosec;
2421 fnosec = fsec = 1;
2422 in_save = in_end = orig;
2423
2424 do {
3528a953
CO		 2425 if (*in_end == '"')
2426 open_quote = !open_quote;
2427 if ((*in_end == ',' && open_quote == 0) ||
2428 *in_end == '\0') {
1da177e4
LT		 2429 int len = in_end - in_curr;
2430
2431 if (selinux_option(in_curr, len))
3528a953 2432 take_selinux_option(&sec_curr, in_curr, &fsec, len);
1da177e4
LT		 2433 else
2434 take_option(&nosec, in_curr, &fnosec, len);
2435
2436 in_curr = in_end + 1;
2437 }
2438 } while (*in_end++);
2439
6931dfc9 2440 strcpy(in_save, nosec_save);
da3caa20 2441 free_page((unsigned long)nosec_save);
1da177e4
LT		 2442out:
2443 return rc;
2444}
2445
2446static int selinux_sb_kern_mount(struct super_block *sb, void *data)
2447{
2448 struct avc_audit_data ad;
2449 int rc;
2450
2451 rc = superblock_doinit(sb, data);
2452 if (rc)
2453 return rc;
2454
828dfe1d 2455 AVC_AUDIT_DATA_INIT(&ad, FS);
44707fdf 2456 ad.u.fs.path.dentry = sb->s_root;
1da177e4
LT		 2457 return superblock_has_perm(current, sb, FILESYSTEM__MOUNT, &ad);
2458}
2459
726c3342 2460static int selinux_sb_statfs(struct dentry *dentry)
1da177e4
LT		 2461{
2462 struct avc_audit_data ad;
2463
828dfe1d 2464 AVC_AUDIT_DATA_INIT(&ad, FS);
44707fdf 2465 ad.u.fs.path.dentry = dentry->d_sb->s_root;
726c3342 2466 return superblock_has_perm(current, dentry->d_sb, FILESYSTEM__GETATTR, &ad);
1da177e4
LT		 2467}
2468
828dfe1d 2469static int selinux_mount(char *dev_name,
b5266eb4 2470 struct path *path,
828dfe1d
EP		 2471 char *type,
2472 unsigned long flags,
2473 void *data)
1da177e4
LT		 2474{
2475 int rc;
2476
b5266eb4 2477 rc = secondary_ops->sb_mount(dev_name, path, type, flags, data);
1da177e4
LT		 2478 if (rc)
2479 return rc;
2480
2481 if (flags & MS_REMOUNT)
b5266eb4 2482 return superblock_has_perm(current, path->mnt->mnt_sb,
828dfe1d 2483 FILESYSTEM__REMOUNT, NULL);
1da177e4 2484 else
b5266eb4 2485 return dentry_has_perm(current, path->mnt, path->dentry,
828dfe1d 2486 FILE__MOUNTON);
1da177e4
LT		 2487}
2488
2489static int selinux_umount(struct vfsmount *mnt, int flags)
2490{
2491 int rc;
2492
2493 rc = secondary_ops->sb_umount(mnt, flags);
2494 if (rc)
2495 return rc;
2496
828dfe1d
EP		 2497 return superblock_has_perm(current, mnt->mnt_sb,
2498 FILESYSTEM__UNMOUNT, NULL);
1da177e4
LT		 2499}
2500
2501/* inode security operations */
2502
2503static int selinux_inode_alloc_security(struct inode *inode)
2504{
2505 return inode_alloc_security(inode);
2506}
2507
2508static void selinux_inode_free_security(struct inode *inode)
2509{
2510 inode_free_security(inode);
2511}
2512
5e41ff9e
SS		 2513static int selinux_inode_init_security(struct inode *inode, struct inode *dir,
2514 char **name, void **value,
2515 size_t *len)
2516{
2517 struct task_security_struct *tsec;
2518 struct inode_security_struct *dsec;
2519 struct superblock_security_struct *sbsec;
570bc1c2 2520 u32 newsid, clen;
5e41ff9e 2521 int rc;
570bc1c2 2522 char *namep = NULL, *context;
5e41ff9e
SS		 2523
2524 tsec = current->security;
2525 dsec = dir->i_security;
2526 sbsec = dir->i_sb->s_security;
5e41ff9e
SS		 2527
2528 if (tsec->create_sid && sbsec->behavior != SECURITY_FS_USE_MNTPOINT) {
2529 newsid = tsec->create_sid;
2530 } else {
2531 rc = security_transition_sid(tsec->sid, dsec->sid,
2532 inode_mode_to_security_class(inode->i_mode),
2533 &newsid);
2534 if (rc) {
2535 printk(KERN_WARNING "%s: "
2536 "security_transition_sid failed, rc=%d (dev=%s "
2537 "ino=%ld)\n",
dd6f953a 2538 __func__,
5e41ff9e
SS		 2539 -rc, inode->i_sb->s_id, inode->i_ino);
2540 return rc;
2541 }
2542 }
2543
296fddf7
EP		 2544 /* Possibly defer initialization to selinux_complete_init. */
2545 if (sbsec->initialized) {
2546 struct inode_security_struct *isec = inode->i_security;
2547 isec->sclass = inode_mode_to_security_class(inode->i_mode);
2548 isec->sid = newsid;
2549 isec->initialized = 1;
2550 }
5e41ff9e 2551
8aad3875 2552 if (!ss_initialized || sbsec->behavior == SECURITY_FS_USE_MNTPOINT)
25a74f3b
SS		 2553 return -EOPNOTSUPP;
2554
570bc1c2 2555 if (name) {
a02fe132 2556 namep = kstrdup(XATTR_SELINUX_SUFFIX, GFP_NOFS);
570bc1c2
SS		 2557 if (!namep)
2558 return -ENOMEM;
2559 *name = namep;
2560 }
5e41ff9e 2561
570bc1c2 2562 if (value && len) {
12b29f34 2563 rc = security_sid_to_context_force(newsid, &context, &clen);
570bc1c2
SS		 2564 if (rc) {
2565 kfree(namep);
2566 return rc;
2567 }
2568 *value = context;
2569 *len = clen;
5e41ff9e 2570 }
5e41ff9e 2571
5e41ff9e
SS		 2572 return 0;
2573}
2574
1da177e4
LT		 2575static int selinux_inode_create(struct inode *dir, struct dentry *dentry, int mask)
2576{
2577 return may_create(dir, dentry, SECCLASS_FILE);
2578}
2579
1da177e4
LT		 2580static int selinux_inode_link(struct dentry *old_dentry, struct inode *dir, struct dentry *new_dentry)
2581{
2582 int rc;
2583
828dfe1d 2584 rc = secondary_ops->inode_link(old_dentry, dir, new_dentry);
1da177e4
LT		 2585 if (rc)
2586 return rc;
2587 return may_link(dir, old_dentry, MAY_LINK);
2588}
2589
1da177e4
LT		 2590static int selinux_inode_unlink(struct inode *dir, struct dentry *dentry)
2591{
2592 int rc;
2593
2594 rc = secondary_ops->inode_unlink(dir, dentry);
2595 if (rc)
2596 return rc;
2597 return may_link(dir, dentry, MAY_UNLINK);
2598}
2599
2600static int selinux_inode_symlink(struct inode *dir, struct dentry *dentry, const char *name)
2601{
2602 return may_create(dir, dentry, SECCLASS_LNK_FILE);
2603}
2604
1da177e4
LT		 2605static int selinux_inode_mkdir(struct inode *dir, struct dentry *dentry, int mask)
2606{
2607 return may_create(dir, dentry, SECCLASS_DIR);
2608}
2609
1da177e4
LT		 2610static int selinux_inode_rmdir(struct inode *dir, struct dentry *dentry)
2611{
2612 return may_link(dir, dentry, MAY_RMDIR);
2613}
2614
2615static int selinux_inode_mknod(struct inode *dir, struct dentry *dentry, int mode, dev_t dev)
2616{
2617 int rc;
2618
2619 rc = secondary_ops->inode_mknod(dir, dentry, mode, dev);
2620 if (rc)
2621 return rc;
2622
2623 return may_create(dir, dentry, inode_mode_to_security_class(mode));
2624}
2625
1da177e4 2626static int selinux_inode_rename(struct inode *old_inode, struct dentry *old_dentry,
828dfe1d 2627 struct inode *new_inode, struct dentry *new_dentry)
1da177e4
LT		 2628{
2629 return may_rename(old_inode, old_dentry, new_inode, new_dentry);
2630}
2631
1da177e4
LT		 2632static int selinux_inode_readlink(struct dentry *dentry)
2633{
2634 return dentry_has_perm(current, NULL, dentry, FILE__READ);
2635}
2636
2637static int selinux_inode_follow_link(struct dentry *dentry, struct nameidata *nameidata)
2638{
2639 int rc;
2640
828dfe1d 2641 rc = secondary_ops->inode_follow_link(dentry, nameidata);
1da177e4
LT		 2642 if (rc)
2643 return rc;
2644 return dentry_has_perm(current, NULL, dentry, FILE__READ);
2645}
2646
b77b0646 2647static int selinux_inode_permission(struct inode *inode, int mask)
1da177e4
LT		 2648{
2649 int rc;
2650
b77b0646 2651 rc = secondary_ops->inode_permission(inode, mask);
1da177e4
LT		 2652 if (rc)
2653 return rc;
2654
2655 if (!mask) {
2656 /* No permission to check. Existence test. */
2657 return 0;
2658 }
2659
2660 return inode_has_perm(current, inode,
8b6a5a37 2661 file_mask_to_av(inode->i_mode, mask), NULL);
1da177e4
LT		 2662}
2663
2664static int selinux_inode_setattr(struct dentry *dentry, struct iattr *iattr)
2665{
2666 int rc;
2667
2668 rc = secondary_ops->inode_setattr(dentry, iattr);
2669 if (rc)
2670 return rc;
2671
2672 if (iattr->ia_valid & ATTR_FORCE)
2673 return 0;
2674
2675 if (iattr->ia_valid & (ATTR_MODE | ATTR_UID | ATTR_GID |
2676 ATTR_ATIME_SET | ATTR_MTIME_SET))
2677 return dentry_has_perm(current, NULL, dentry, FILE__SETATTR);
2678
2679 return dentry_has_perm(current, NULL, dentry, FILE__WRITE);
2680}
2681
2682static int selinux_inode_getattr(struct vfsmount *mnt, struct dentry *dentry)
2683{
2684 return dentry_has_perm(current, mnt, dentry, FILE__GETATTR);
2685}
2686
8f0cfa52 2687static int selinux_inode_setotherxattr(struct dentry *dentry, const char *name)
b5376771
SH		 2688{
2689 if (!strncmp(name, XATTR_SECURITY_PREFIX,
2690 sizeof XATTR_SECURITY_PREFIX - 1)) {
2691 if (!strcmp(name, XATTR_NAME_CAPS)) {
2692 if (!capable(CAP_SETFCAP))
2693 return -EPERM;
2694 } else if (!capable(CAP_SYS_ADMIN)) {
2695 /* A different attribute in the security namespace.
2696 Restrict to administrator. */
2697 return -EPERM;
2698 }
2699 }
2700
2701 /* Not an attribute we recognize, so just check the
2702 ordinary setattr permission. */
2703 return dentry_has_perm(current, NULL, dentry, FILE__SETATTR);
2704}
2705
8f0cfa52
DH		 2706static int selinux_inode_setxattr(struct dentry *dentry, const char *name,
2707 const void *value, size_t size, int flags)
1da177e4
LT		 2708{
2709 struct task_security_struct *tsec = current->security;
2710 struct inode *inode = dentry->d_inode;
2711 struct inode_security_struct *isec = inode->i_security;
2712 struct superblock_security_struct *sbsec;
2713 struct avc_audit_data ad;
2714 u32 newsid;
2715 int rc = 0;
2716
b5376771
SH		 2717 if (strcmp(name, XATTR_NAME_SELINUX))
2718 return selinux_inode_setotherxattr(dentry, name);
1da177e4
LT		 2719
2720 sbsec = inode->i_sb->s_security;
2721 if (sbsec->behavior == SECURITY_FS_USE_MNTPOINT)
2722 return -EOPNOTSUPP;
2723
3bd858ab 2724 if (!is_owner_or_cap(inode))
1da177e4
LT		 2725 return -EPERM;
2726
828dfe1d 2727 AVC_AUDIT_DATA_INIT(&ad, FS);
44707fdf 2728 ad.u.fs.path.dentry = dentry;
1da177e4
LT		 2729
2730 rc = avc_has_perm(tsec->sid, isec->sid, isec->sclass,
2731 FILE__RELABELFROM, &ad);
2732 if (rc)
2733 return rc;
2734
2735 rc = security_context_to_sid(value, size, &newsid);
12b29f34
SS		 2736 if (rc == -EINVAL) {
2737 if (!capable(CAP_MAC_ADMIN))
2738 return rc;
2739 rc = security_context_to_sid_force(value, size, &newsid);
2740 }
1da177e4
LT		 2741 if (rc)
2742 return rc;
2743
2744 rc = avc_has_perm(tsec->sid, newsid, isec->sclass,
2745 FILE__RELABELTO, &ad);
2746 if (rc)
2747 return rc;
2748
2749 rc = security_validate_transition(isec->sid, newsid, tsec->sid,
828dfe1d 2750 isec->sclass);
1da177e4
LT		 2751 if (rc)
2752 return rc;
2753
2754 return avc_has_perm(newsid,
2755 sbsec->sid,
2756 SECCLASS_FILESYSTEM,
2757 FILESYSTEM__ASSOCIATE,
2758 &ad);
2759}
2760
8f0cfa52 2761static void selinux_inode_post_setxattr(struct dentry *dentry, const char *name,
f5269710 2762 const void *value, size_t size,
8f0cfa52 2763 int flags)
1da177e4
LT		 2764{
2765 struct inode *inode = dentry->d_inode;
2766 struct inode_security_struct *isec = inode->i_security;
2767 u32 newsid;
2768 int rc;
2769
2770 if (strcmp(name, XATTR_NAME_SELINUX)) {
2771 /* Not an attribute we recognize, so nothing to do. */
2772 return;
2773 }
2774
12b29f34 2775 rc = security_context_to_sid_force(value, size, &newsid);
1da177e4 2776 if (rc) {
12b29f34
SS		 2777 printk(KERN_ERR "SELinux: unable to map context to SID"
2778 "for (%s, %lu), rc=%d\n",
2779 inode->i_sb->s_id, inode->i_ino, -rc);
1da177e4
LT		 2780 return;
2781 }
2782
2783 isec->sid = newsid;
2784 return;
2785}
2786
8f0cfa52 2787static int selinux_inode_getxattr(struct dentry *dentry, const char *name)
1da177e4 2788{
1da177e4
LT		 2789 return dentry_has_perm(current, NULL, dentry, FILE__GETATTR);
2790}
2791
828dfe1d 2792static int selinux_inode_listxattr(struct dentry *dentry)
1da177e4
LT		 2793{
2794 return dentry_has_perm(current, NULL, dentry, FILE__GETATTR);
2795}
2796
8f0cfa52 2797static int selinux_inode_removexattr(struct dentry *dentry, const char *name)
1da177e4 2798{
b5376771
SH		 2799 if (strcmp(name, XATTR_NAME_SELINUX))
2800 return selinux_inode_setotherxattr(dentry, name);
1da177e4
LT		 2801
2802 /* No one is allowed to remove a SELinux security label.
2803 You can change the label, but all data must be labeled. */
2804 return -EACCES;
2805}
2806
d381d8a9 2807/*
abc69bb6 2808 * Copy the inode security context value to the user.
d381d8a9
JM		 2809 *
2810 * Permission check is handled by selinux_inode_getxattr hook.
2811 */
42492594 2812static int selinux_inode_getsecurity(const struct inode *inode, const char *name, void **buffer, bool alloc)
1da177e4 2813{
42492594
DQ		 2814 u32 size;
2815 int error;
2816 char *context = NULL;
abc69bb6 2817 struct task_security_struct *tsec = current->security;
1da177e4 2818 struct inode_security_struct *isec = inode->i_security;
d381d8a9 2819
8c8570fb
DK		 2820 if (strcmp(name, XATTR_SELINUX_SUFFIX))
2821 return -EOPNOTSUPP;
d381d8a9 2822
abc69bb6
SS		 2823 /*
2824 * If the caller has CAP_MAC_ADMIN, then get the raw context
2825 * value even if it is not defined by current policy; otherwise,
2826 * use the in-core value under current policy.
2827 * Use the non-auditing forms of the permission checks since
2828 * getxattr may be called by unprivileged processes commonly
2829 * and lack of permission just means that we fall back to the
2830 * in-core context value, not a denial.
2831 */
2832 error = secondary_ops->capable(current, CAP_MAC_ADMIN);
2833 if (!error)
2834 error = avc_has_perm_noaudit(tsec->sid, tsec->sid,
2835 SECCLASS_CAPABILITY2,
2836 CAPABILITY2__MAC_ADMIN,
2837 0,
2838 NULL);
2839 if (!error)
2840 error = security_sid_to_context_force(isec->sid, &context,
2841 &size);
2842 else
2843 error = security_sid_to_context(isec->sid, &context, &size);
42492594
DQ		 2844 if (error)
2845 return error;
2846 error = size;
2847 if (alloc) {
2848 *buffer = context;
2849 goto out_nofree;
2850 }
2851 kfree(context);
2852out_nofree:
2853 return error;
1da177e4
LT		 2854}
2855
2856static int selinux_inode_setsecurity(struct inode *inode, const char *name,
828dfe1d 2857 const void *value, size_t size, int flags)
1da177e4
LT		 2858{
2859 struct inode_security_struct *isec = inode->i_security;
2860 u32 newsid;
2861 int rc;
2862
2863 if (strcmp(name, XATTR_SELINUX_SUFFIX))
2864 return -EOPNOTSUPP;
2865
2866 if (!value || !size)
2867 return -EACCES;
2868
828dfe1d 2869 rc = security_context_to_sid((void *)value, size, &newsid);
1da177e4
LT		 2870 if (rc)
2871 return rc;
2872
2873 isec->sid = newsid;
2874 return 0;
2875}
2876
2877static int selinux_inode_listsecurity(struct inode *inode, char *buffer, size_t buffer_size)
2878{
2879 const int len = sizeof(XATTR_NAME_SELINUX);
2880 if (buffer && len <= buffer_size)
2881 memcpy(buffer, XATTR_NAME_SELINUX, len);
2882 return len;
2883}
2884
b5376771
SH		 2885static int selinux_inode_need_killpriv(struct dentry *dentry)
2886{
2887 return secondary_ops->inode_need_killpriv(dentry);
2888}
2889
2890static int selinux_inode_killpriv(struct dentry *dentry)
2891{
2892 return secondary_ops->inode_killpriv(dentry);
2893}
2894
713a04ae
AD		 2895static void selinux_inode_getsecid(const struct inode *inode, u32 *secid)
2896{
2897 struct inode_security_struct *isec = inode->i_security;
2898 *secid = isec->sid;
2899}
2900
1da177e4
LT		 2901/* file security operations */
2902
788e7dd4 2903static int selinux_revalidate_file_permission(struct file *file, int mask)
1da177e4 2904{
7420ed23 2905 int rc;
3d5ff529 2906 struct inode *inode = file->f_path.dentry->d_inode;
1da177e4
LT		 2907
2908 if (!mask) {
2909 /* No permission to check. Existence test. */
2910 return 0;
2911 }
2912
2913 /* file_mask_to_av won't add FILE__WRITE if MAY_APPEND is set */
2914 if ((file->f_flags & O_APPEND) && (mask & MAY_WRITE))
2915 mask |= MAY_APPEND;
2916
7420ed23
VY		 2917 rc = file_has_perm(current, file,
2918 file_mask_to_av(inode->i_mode, mask));
2919 if (rc)
2920 return rc;
2921
2922 return selinux_netlbl_inode_permission(inode, mask);
1da177e4
LT		 2923}
2924
788e7dd4
YN		 2925static int selinux_file_permission(struct file *file, int mask)
2926{
2927 struct inode *inode = file->f_path.dentry->d_inode;
2928 struct task_security_struct *tsec = current->security;
2929 struct file_security_struct *fsec = file->f_security;
2930 struct inode_security_struct *isec = inode->i_security;
2931
2932 if (!mask) {
2933 /* No permission to check. Existence test. */
2934 return 0;
2935 }
2936
2937 if (tsec->sid == fsec->sid && fsec->isid == isec->sid
2938 && fsec->pseqno == avc_policy_seqno())
2939 return selinux_netlbl_inode_permission(inode, mask);
2940
2941 return selinux_revalidate_file_permission(file, mask);
2942}
2943
1da177e4
LT		 2944static int selinux_file_alloc_security(struct file *file)
2945{
2946 return file_alloc_security(file);
2947}
2948
2949static void selinux_file_free_security(struct file *file)
2950{
2951 file_free_security(file);
2952}
2953
2954static int selinux_file_ioctl(struct file *file, unsigned int cmd,
2955 unsigned long arg)
2956{
242631c4 2957 u32 av = 0;
1da177e4 2958
242631c4
SS		 2959 if (_IOC_DIR(cmd) & _IOC_WRITE)
2960 av |= FILE__WRITE;
2961 if (_IOC_DIR(cmd) & _IOC_READ)
2962 av |= FILE__READ;
2963 if (!av)
2964 av = FILE__IOCTL;
1da177e4 2965
242631c4 2966 return file_has_perm(current, file, av);
1da177e4
LT		 2967}
2968
2969static int file_map_prot_check(struct file *file, unsigned long prot, int shared)
2970{
2971#ifndef CONFIG_PPC32
2972 if ((prot & PROT_EXEC) && (!file || (!shared && (prot & PROT_WRITE)))) {
2973 /*
2974 * We are making executable an anonymous mapping or a
2975 * private file mapping that will also be writable.
2976 * This has an additional check.
2977 */
2978 int rc = task_has_perm(current, current, PROCESS__EXECMEM);
2979 if (rc)
2980 return rc;
2981 }
2982#endif
2983
2984 if (file) {
2985 /* read access is always possible with a mapping */
2986 u32 av = FILE__READ;
2987
2988 /* write access only matters if the mapping is shared */
2989 if (shared && (prot & PROT_WRITE))
2990 av |= FILE__WRITE;
2991
2992 if (prot & PROT_EXEC)
2993 av |= FILE__EXECUTE;
2994
2995 return file_has_perm(current, file, av);
2996 }
2997 return 0;
2998}
2999
3000static int selinux_file_mmap(struct file *file, unsigned long reqprot,
ed032189
EP		 3001 unsigned long prot, unsigned long flags,
3002 unsigned long addr, unsigned long addr_only)
1da177e4 3003{
ed032189 3004 int rc = 0;
828dfe1d 3005 u32 sid = ((struct task_security_struct *)(current->security))->sid;
1da177e4 3006
ed032189
EP		 3007 if (addr < mmap_min_addr)
3008 rc = avc_has_perm(sid, sid, SECCLASS_MEMPROTECT,
3009 MEMPROTECT__MMAP_ZERO, NULL);
3010 if (rc || addr_only)
1da177e4
LT		 3011 return rc;
3012
3013 if (selinux_checkreqprot)
3014 prot = reqprot;
3015
3016 return file_map_prot_check(file, prot,
3017 (flags & MAP_TYPE) == MAP_SHARED);
3018}
3019
3020static int selinux_file_mprotect(struct vm_area_struct *vma,
3021 unsigned long reqprot,
3022 unsigned long prot)
3023{
3024 int rc;
3025
3026 rc = secondary_ops->file_mprotect(vma, reqprot, prot);
3027 if (rc)
3028 return rc;
3029
3030 if (selinux_checkreqprot)
3031 prot = reqprot;
3032
3033#ifndef CONFIG_PPC32
db4c9641
SS		 3034 if ((prot & PROT_EXEC) && !(vma->vm_flags & VM_EXEC)) {
3035 rc = 0;
3036 if (vma->vm_start >= vma->vm_mm->start_brk &&
3037 vma->vm_end <= vma->vm_mm->brk) {
3038 rc = task_has_perm(current, current,
3039 PROCESS__EXECHEAP);
3040 } else if (!vma->vm_file &&
3041 vma->vm_start <= vma->vm_mm->start_stack &&
3042 vma->vm_end >= vma->vm_mm->start_stack) {
3043 rc = task_has_perm(current, current, PROCESS__EXECSTACK);
3044 } else if (vma->vm_file && vma->anon_vma) {
3045 /*
3046 * We are making executable a file mapping that has
3047 * had some COW done. Since pages might have been
3048 * written, check ability to execute the possibly
3049 * modified content. This typically should only
3050 * occur for text relocations.
3051 */
3052 rc = file_has_perm(current, vma->vm_file,
3053 FILE__EXECMOD);
3054 }