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[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>
788e7dd4
YN		 17 * Copyright (C) 2007 Hitachi Software Engineering Co., Ltd.
18 * Yuichi Nakamura <ynakam@hitachisoft.jp>
1da177e4
LT		 19 *
20 * This program is free software; you can redistribute it and/or modify
21 * it under the terms of the GNU General Public License version 2,
22 * as published by the Free Software Foundation.
23 */
24
1da177e4
LT		 25#include <linux/module.h>
26#include <linux/init.h>
27#include <linux/kernel.h>
28#include <linux/ptrace.h>
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>
43#include <linux/namei.h>
44#include <linux/mount.h>
45#include <linux/ext2_fs.h>
46#include <linux/proc_fs.h>
47#include <linux/kd.h>
48#include <linux/netfilter_ipv4.h>
49#include <linux/netfilter_ipv6.h>
50#include <linux/tty.h>
51#include <net/icmp.h>
227b60f5 52#include <net/ip.h> /* for local_port_range[] */
1da177e4
LT		 53#include <net/tcp.h> /* struct or_callable used in sock_rcv_skb */
54#include <asm/uaccess.h>
1da177e4
LT		 55#include <asm/ioctls.h>
56#include <linux/bitops.h>
57#include <linux/interrupt.h>
58#include <linux/netdevice.h> /* for network interface checks */
59#include <linux/netlink.h>
60#include <linux/tcp.h>
61#include <linux/udp.h>
2ee92d46 62#include <linux/dccp.h>
1da177e4
LT		 63#include <linux/quota.h>
64#include <linux/un.h> /* for Unix socket types */
65#include <net/af_unix.h> /* for Unix socket types */
66#include <linux/parser.h>
67#include <linux/nfs_mount.h>
68#include <net/ipv6.h>
69#include <linux/hugetlb.h>
70#include <linux/personality.h>
71#include <linux/sysctl.h>
72#include <linux/audit.h>
6931dfc9 73#include <linux/string.h>
877ce7c1 74#include <linux/selinux.h>
23970741 75#include <linux/mutex.h>
1da177e4
LT		 76
77#include "avc.h"
78#include "objsec.h"
79#include "netif.h"
d28d1e08 80#include "xfrm.h"
c60475bf 81#include "netlabel.h"
1da177e4
LT		 82
83#define XATTR_SELINUX_SUFFIX "selinux"
84#define XATTR_NAME_SELINUX XATTR_SECURITY_PREFIX XATTR_SELINUX_SUFFIX
85
86extern unsigned int policydb_loaded_version;
87extern int selinux_nlmsg_lookup(u16 sclass, u16 nlmsg_type, u32 *perm);
4e5ab4cb 88extern int selinux_compat_net;
1da177e4
LT		 89
90#ifdef CONFIG_SECURITY_SELINUX_DEVELOP
91int selinux_enforcing = 0;
92
93static int __init enforcing_setup(char *str)
94{
95 selinux_enforcing = simple_strtol(str,NULL,0);
96 return 1;
97}
98__setup("enforcing=", enforcing_setup);
99#endif
100
101#ifdef CONFIG_SECURITY_SELINUX_BOOTPARAM
102int selinux_enabled = CONFIG_SECURITY_SELINUX_BOOTPARAM_VALUE;
103
104static int __init selinux_enabled_setup(char *str)
105{
106 selinux_enabled = simple_strtol(str, NULL, 0);
107 return 1;
108}
109__setup("selinux=", selinux_enabled_setup);
30d55280
SS		 110#else
111int selinux_enabled = 1;
1da177e4
LT		 112#endif
113
114/* Original (dummy) security module. */
115static struct security_operations *original_ops = NULL;
116
117/* Minimal support for a secondary security module,
118 just to allow the use of the dummy or capability modules.
119 The owlsm module can alternatively be used as a secondary
120 module as long as CONFIG_OWLSM_FD is not enabled. */
121static struct security_operations *secondary_ops = NULL;
122
123/* Lists of inode and superblock security structures initialized
124 before the policy was loaded. */
125static LIST_HEAD(superblock_security_head);
126static DEFINE_SPINLOCK(sb_security_lock);
127
e18b890b 128static struct kmem_cache *sel_inode_cache;
7cae7e26 129
8c8570fb
DK		 130/* Return security context for a given sid or just the context
131 length if the buffer is null or length is 0 */
132static int selinux_getsecurity(u32 sid, void *buffer, size_t size)
133{
134 char *context;
135 unsigned len;
136 int rc;
137
138 rc = security_sid_to_context(sid, &context, &len);
139 if (rc)
140 return rc;
141
142 if (!buffer || !size)
143 goto getsecurity_exit;
144
145 if (size < len) {
146 len = -ERANGE;
147 goto getsecurity_exit;
148 }
149 memcpy(buffer, context, len);
150
151getsecurity_exit:
152 kfree(context);
153 return len;
154}
155
1da177e4
LT		 156/* Allocate and free functions for each kind of security blob. */
157
158static int task_alloc_security(struct task_struct *task)
159{
160 struct task_security_struct *tsec;
161
89d155ef 162 tsec = kzalloc(sizeof(struct task_security_struct), GFP_KERNEL);
1da177e4
LT		 163 if (!tsec)
164 return -ENOMEM;
165
1da177e4
LT		 166 tsec->task = task;
167 tsec->osid = tsec->sid = tsec->ptrace_sid = SECINITSID_UNLABELED;
168 task->security = tsec;
169
170 return 0;
171}
172
173static void task_free_security(struct task_struct *task)
174{
175 struct task_security_struct *tsec = task->security;
1da177e4
LT		 176 task->security = NULL;
177 kfree(tsec);
178}
179
180static int inode_alloc_security(struct inode *inode)
181{
182 struct task_security_struct *tsec = current->security;
183 struct inode_security_struct *isec;
184
c3762229 185 isec = kmem_cache_zalloc(sel_inode_cache, GFP_KERNEL);
1da177e4
LT		 186 if (!isec)
187 return -ENOMEM;
188
23970741 189 mutex_init(&isec->lock);
1da177e4 190 INIT_LIST_HEAD(&isec->list);
1da177e4
LT		 191 isec->inode = inode;
192 isec->sid = SECINITSID_UNLABELED;
193 isec->sclass = SECCLASS_FILE;
9ac49d22 194 isec->task_sid = tsec->sid;
1da177e4
LT		 195 inode->i_security = isec;
196
197 return 0;
198}
199
200static void inode_free_security(struct inode *inode)
201{
202 struct inode_security_struct *isec = inode->i_security;
203 struct superblock_security_struct *sbsec = inode->i_sb->s_security;
204
1da177e4
LT		 205 spin_lock(&sbsec->isec_lock);
206 if (!list_empty(&isec->list))
207 list_del_init(&isec->list);
208 spin_unlock(&sbsec->isec_lock);
209
210 inode->i_security = NULL;
7cae7e26 211 kmem_cache_free(sel_inode_cache, isec);
1da177e4
LT		 212}
213
214static int file_alloc_security(struct file *file)
215{
216 struct task_security_struct *tsec = current->security;
217 struct file_security_struct *fsec;
218
26d2a4be 219 fsec = kzalloc(sizeof(struct file_security_struct), GFP_KERNEL);
1da177e4
LT		 220 if (!fsec)
221 return -ENOMEM;
222
1da177e4 223 fsec->file = file;
9ac49d22
SS		 224 fsec->sid = tsec->sid;
225 fsec->fown_sid = tsec->sid;
1da177e4
LT		 226 file->f_security = fsec;
227
228 return 0;
229}
230
231static void file_free_security(struct file *file)
232{
233 struct file_security_struct *fsec = file->f_security;
1da177e4
LT		 234 file->f_security = NULL;
235 kfree(fsec);
236}
237
238static int superblock_alloc_security(struct super_block *sb)
239{
240 struct superblock_security_struct *sbsec;
241
89d155ef 242 sbsec = kzalloc(sizeof(struct superblock_security_struct), GFP_KERNEL);
1da177e4
LT		 243 if (!sbsec)
244 return -ENOMEM;
245
bc7e982b 246 mutex_init(&sbsec->lock);
1da177e4
LT		 247 INIT_LIST_HEAD(&sbsec->list);
248 INIT_LIST_HEAD(&sbsec->isec_head);
249 spin_lock_init(&sbsec->isec_lock);
1da177e4
LT		 250 sbsec->sb = sb;
251 sbsec->sid = SECINITSID_UNLABELED;
252 sbsec->def_sid = SECINITSID_FILE;
c312feb2 253 sbsec->mntpoint_sid = SECINITSID_UNLABELED;
1da177e4
LT		 254 sb->s_security = sbsec;
255
256 return 0;
257}
258
259static void superblock_free_security(struct super_block *sb)
260{
261 struct superblock_security_struct *sbsec = sb->s_security;
262
1da177e4
LT		 263 spin_lock(&sb_security_lock);
264 if (!list_empty(&sbsec->list))
265 list_del_init(&sbsec->list);
266 spin_unlock(&sb_security_lock);
267
268 sb->s_security = NULL;
269 kfree(sbsec);
270}
271
7d877f3b 272static int sk_alloc_security(struct sock *sk, int family, gfp_t priority)
1da177e4
LT		 273{
274 struct sk_security_struct *ssec;
275
89d155ef 276 ssec = kzalloc(sizeof(*ssec), priority);
1da177e4
LT		 277 if (!ssec)
278 return -ENOMEM;
279
1da177e4
LT		 280 ssec->sk = sk;
281 ssec->peer_sid = SECINITSID_UNLABELED;
892c141e 282 ssec->sid = SECINITSID_UNLABELED;
1da177e4
LT		 283 sk->sk_security = ssec;
284
99f59ed0
PM		 285 selinux_netlbl_sk_security_init(ssec, family);
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
LT		 294 sk->sk_security = NULL;
295 kfree(ssec);
296}
1da177e4
LT		 297
298/* The security server must be initialized before
299 any labeling or access decisions can be provided. */
300extern int ss_initialized;
301
302/* The file system's label must be initialized prior to use. */
303
304static char *labeling_behaviors[6] = {
305 "uses xattr",
306 "uses transition SIDs",
307 "uses task SIDs",
308 "uses genfs_contexts",
309 "not configured for labeling",
310 "uses mountpoint labeling",
311};
312
313static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dentry);
314
315static inline int inode_doinit(struct inode *inode)
316{
317 return inode_doinit_with_dentry(inode, NULL);
318}
319
320enum {
31e87930 321 Opt_error = -1,
1da177e4
LT		 322 Opt_context = 1,
323 Opt_fscontext = 2,
324 Opt_defcontext = 4,
0808925e 325 Opt_rootcontext = 8,
1da177e4
LT		 326};
327
328static match_table_t tokens = {
329 {Opt_context, "context=%s"},
330 {Opt_fscontext, "fscontext=%s"},
331 {Opt_defcontext, "defcontext=%s"},
0808925e 332 {Opt_rootcontext, "rootcontext=%s"},
31e87930 333 {Opt_error, NULL},
1da177e4
LT		 334};
335
336#define SEL_MOUNT_FAIL_MSG "SELinux: duplicate or incompatible mount options\n"
337
c312feb2
EP		 338static int may_context_mount_sb_relabel(u32 sid,
339 struct superblock_security_struct *sbsec,
340 struct task_security_struct *tsec)
341{
342 int rc;
343
344 rc = avc_has_perm(tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM,
345 FILESYSTEM__RELABELFROM, NULL);
346 if (rc)
347 return rc;
348
349 rc = avc_has_perm(tsec->sid, sid, SECCLASS_FILESYSTEM,
350 FILESYSTEM__RELABELTO, NULL);
351 return rc;
352}
353
0808925e
EP		 354static int may_context_mount_inode_relabel(u32 sid,
355 struct superblock_security_struct *sbsec,
356 struct task_security_struct *tsec)
357{
358 int rc;
359 rc = avc_has_perm(tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM,
360 FILESYSTEM__RELABELFROM, NULL);
361 if (rc)
362 return rc;
363
364 rc = avc_has_perm(sid, sbsec->sid, SECCLASS_FILESYSTEM,
365 FILESYSTEM__ASSOCIATE, NULL);
366 return rc;
367}
368
1da177e4
LT		 369static int try_context_mount(struct super_block *sb, void *data)
370{
371 char *context = NULL, *defcontext = NULL;
0808925e 372 char *fscontext = NULL, *rootcontext = NULL;
1da177e4
LT		 373 const char *name;
374 u32 sid;
375 int alloc = 0, rc = 0, seen = 0;
376 struct task_security_struct *tsec = current->security;
377 struct superblock_security_struct *sbsec = sb->s_security;
378
379 if (!data)
380 goto out;
381
382 name = sb->s_type->name;
383
384 if (sb->s_type->fs_flags & FS_BINARY_MOUNTDATA) {
385
386 /* NFS we understand. */
387 if (!strcmp(name, "nfs")) {
388 struct nfs_mount_data *d = data;
389
390 if (d->version < NFS_MOUNT_VERSION)
391 goto out;
392
393 if (d->context[0]) {
394 context = d->context;
395 seen |= Opt_context;
396 }
397 } else
398 goto out;
399
400 } else {
401 /* Standard string-based options. */
402 char *p, *options = data;
403
3528a953 404 while ((p = strsep(&options, "|")) != NULL) {
1da177e4
LT		 405 int token;
406 substring_t args[MAX_OPT_ARGS];
407
408 if (!*p)
409 continue;
410
411 token = match_token(p, tokens, args);
412
413 switch (token) {
414 case Opt_context:
c312feb2 415 if (seen & (Opt_context|Opt_defcontext)) {
1da177e4
LT		 416 rc = -EINVAL;
417 printk(KERN_WARNING SEL_MOUNT_FAIL_MSG);
418 goto out_free;
419 }
420 context = match_strdup(&args[0]);
421 if (!context) {
422 rc = -ENOMEM;
423 goto out_free;
424 }
425 if (!alloc)
426 alloc = 1;
427 seen |= Opt_context;
428 break;
429
430 case Opt_fscontext:
c312feb2 431 if (seen & Opt_fscontext) {
1da177e4
LT		 432 rc = -EINVAL;
433 printk(KERN_WARNING SEL_MOUNT_FAIL_MSG);
434 goto out_free;
435 }
c312feb2
EP		 436 fscontext = match_strdup(&args[0]);
437 if (!fscontext) {
1da177e4
LT		 438 rc = -ENOMEM;
439 goto out_free;
440 }
441 if (!alloc)
442 alloc = 1;
443 seen |= Opt_fscontext;
444 break;
445
0808925e
EP		 446 case Opt_rootcontext:
447 if (seen & Opt_rootcontext) {
448 rc = -EINVAL;
449 printk(KERN_WARNING SEL_MOUNT_FAIL_MSG);
450 goto out_free;
451 }
452 rootcontext = match_strdup(&args[0]);
453 if (!rootcontext) {
454 rc = -ENOMEM;
455 goto out_free;
456 }
457 if (!alloc)
458 alloc = 1;
459 seen |= Opt_rootcontext;
460 break;
461
1da177e4
LT		 462 case Opt_defcontext:
463 if (sbsec->behavior != SECURITY_FS_USE_XATTR) {
464 rc = -EINVAL;
465 printk(KERN_WARNING "SELinux: "
466 "defcontext option is invalid "
467 "for this filesystem type\n");
468 goto out_free;
469 }
470 if (seen & (Opt_context|Opt_defcontext)) {
471 rc = -EINVAL;
472 printk(KERN_WARNING SEL_MOUNT_FAIL_MSG);
473 goto out_free;
474 }
475 defcontext = match_strdup(&args[0]);
476 if (!defcontext) {
477 rc = -ENOMEM;
478 goto out_free;
479 }
480 if (!alloc)
481 alloc = 1;
482 seen |= Opt_defcontext;
483 break;
484
485 default:
486 rc = -EINVAL;
487 printk(KERN_WARNING "SELinux: unknown mount "
488 "option\n");
489 goto out_free;
490
491 }
492 }
493 }
494
495 if (!seen)
496 goto out;
497
c312feb2
EP		 498 /* sets the context of the superblock for the fs being mounted. */
499 if (fscontext) {
500 rc = security_context_to_sid(fscontext, strlen(fscontext), &sid);
1da177e4
LT		 501 if (rc) {
502 printk(KERN_WARNING "SELinux: security_context_to_sid"
503 "(%s) failed for (dev %s, type %s) errno=%d\n",
c312feb2 504 fscontext, sb->s_id, name, rc);
1da177e4
LT		 505 goto out_free;
506 }
507
c312feb2 508 rc = may_context_mount_sb_relabel(sid, sbsec, tsec);
1da177e4
LT		 509 if (rc)
510 goto out_free;
511
c312feb2
EP		 512 sbsec->sid = sid;
513 }
514
515 /*
516 * Switch to using mount point labeling behavior.
517 * sets the label used on all file below the mountpoint, and will set
518 * the superblock context if not already set.
519 */
520 if (context) {
521 rc = security_context_to_sid(context, strlen(context), &sid);
522 if (rc) {
523 printk(KERN_WARNING "SELinux: security_context_to_sid"
524 "(%s) failed for (dev %s, type %s) errno=%d\n",
525 context, sb->s_id, name, rc);
526 goto out_free;
527 }
528
b04ea3ce
EP		 529 if (!fscontext) {
530 rc = may_context_mount_sb_relabel(sid, sbsec, tsec);
531 if (rc)
532 goto out_free;
c312feb2 533 sbsec->sid = sid;
b04ea3ce
EP		 534 } else {
535 rc = may_context_mount_inode_relabel(sid, sbsec, tsec);
536 if (rc)
537 goto out_free;
538 }
c312feb2 539 sbsec->mntpoint_sid = sid;
1da177e4 540
c312feb2 541 sbsec->behavior = SECURITY_FS_USE_MNTPOINT;
1da177e4
LT		 542 }
543
0808925e
EP		 544 if (rootcontext) {
545 struct inode *inode = sb->s_root->d_inode;
546 struct inode_security_struct *isec = inode->i_security;
547 rc = security_context_to_sid(rootcontext, strlen(rootcontext), &sid);
548 if (rc) {
549 printk(KERN_WARNING "SELinux: security_context_to_sid"
550 "(%s) failed for (dev %s, type %s) errno=%d\n",
551 rootcontext, sb->s_id, name, rc);
552 goto out_free;
553 }
554
555 rc = may_context_mount_inode_relabel(sid, sbsec, tsec);
556 if (rc)
557 goto out_free;
558
559 isec->sid = sid;
560 isec->initialized = 1;
561 }
562
1da177e4
LT		 563 if (defcontext) {
564 rc = security_context_to_sid(defcontext, strlen(defcontext), &sid);
565 if (rc) {
566 printk(KERN_WARNING "SELinux: security_context_to_sid"
567 "(%s) failed for (dev %s, type %s) errno=%d\n",
568 defcontext, sb->s_id, name, rc);
569 goto out_free;
570 }
571
572 if (sid == sbsec->def_sid)
573 goto out_free;
574
0808925e 575 rc = may_context_mount_inode_relabel(sid, sbsec, tsec);
1da177e4
LT		 576 if (rc)
577 goto out_free;
578
579 sbsec->def_sid = sid;
580 }
581
582out_free:
583 if (alloc) {
584 kfree(context);
585 kfree(defcontext);
c312feb2 586 kfree(fscontext);
0808925e 587 kfree(rootcontext);
1da177e4
LT		 588 }
589out:
590 return rc;
591}
592
593static int superblock_doinit(struct super_block *sb, void *data)
594{
595 struct superblock_security_struct *sbsec = sb->s_security;
596 struct dentry *root = sb->s_root;
597 struct inode *inode = root->d_inode;
598 int rc = 0;
599
bc7e982b 600 mutex_lock(&sbsec->lock);
1da177e4
LT		 601 if (sbsec->initialized)
602 goto out;
603
604 if (!ss_initialized) {
605 /* Defer initialization until selinux_complete_init,
606 after the initial policy is loaded and the security
607 server is ready to handle calls. */
608 spin_lock(&sb_security_lock);
609 if (list_empty(&sbsec->list))
610 list_add(&sbsec->list, &superblock_security_head);
611 spin_unlock(&sb_security_lock);
612 goto out;
613 }
614
615 /* Determine the labeling behavior to use for this filesystem type. */
616 rc = security_fs_use(sb->s_type->name, &sbsec->behavior, &sbsec->sid);
617 if (rc) {
618 printk(KERN_WARNING "%s: security_fs_use(%s) returned %d\n",
619 __FUNCTION__, sb->s_type->name, rc);
620 goto out;
621 }
622
623 rc = try_context_mount(sb, data);
624 if (rc)
625 goto out;
626
627 if (sbsec->behavior == SECURITY_FS_USE_XATTR) {
628 /* Make sure that the xattr handler exists and that no
629 error other than -ENODATA is returned by getxattr on
630 the root directory. -ENODATA is ok, as this may be
631 the first boot of the SELinux kernel before we have
632 assigned xattr values to the filesystem. */
633 if (!inode->i_op->getxattr) {
634 printk(KERN_WARNING "SELinux: (dev %s, type %s) has no "
635 "xattr support\n", sb->s_id, sb->s_type->name);
636 rc = -EOPNOTSUPP;
637 goto out;
638 }
639 rc = inode->i_op->getxattr(root, XATTR_NAME_SELINUX, NULL, 0);
640 if (rc < 0 && rc != -ENODATA) {
641 if (rc == -EOPNOTSUPP)
642 printk(KERN_WARNING "SELinux: (dev %s, type "
643 "%s) has no security xattr handler\n",
644 sb->s_id, sb->s_type->name);
645 else
646 printk(KERN_WARNING "SELinux: (dev %s, type "
647 "%s) getxattr errno %d\n", sb->s_id,
648 sb->s_type->name, -rc);
649 goto out;
650 }
651 }
652
653 if (strcmp(sb->s_type->name, "proc") == 0)
654 sbsec->proc = 1;
655
656 sbsec->initialized = 1;
657
658 if (sbsec->behavior > ARRAY_SIZE(labeling_behaviors)) {
fadcdb45 659 printk(KERN_ERR "SELinux: initialized (dev %s, type %s), unknown behavior\n",
1da177e4
LT		 660 sb->s_id, sb->s_type->name);
661 }
662 else {
fadcdb45 663 printk(KERN_DEBUG "SELinux: initialized (dev %s, type %s), %s\n",
1da177e4
LT		 664 sb->s_id, sb->s_type->name,
665 labeling_behaviors[sbsec->behavior-1]);
666 }
667
668 /* Initialize the root inode. */
669 rc = inode_doinit_with_dentry(sb->s_root->d_inode, sb->s_root);
670
671 /* Initialize any other inodes associated with the superblock, e.g.
672 inodes created prior to initial policy load or inodes created
673 during get_sb by a pseudo filesystem that directly
674 populates itself. */
675 spin_lock(&sbsec->isec_lock);
676next_inode:
677 if (!list_empty(&sbsec->isec_head)) {
678 struct inode_security_struct *isec =
679 list_entry(sbsec->isec_head.next,
680 struct inode_security_struct, list);
681 struct inode *inode = isec->inode;
682 spin_unlock(&sbsec->isec_lock);
683 inode = igrab(inode);
684 if (inode) {
685 if (!IS_PRIVATE (inode))
686 inode_doinit(inode);
687 iput(inode);
688 }
689 spin_lock(&sbsec->isec_lock);
690 list_del_init(&isec->list);
691 goto next_inode;
692 }
693 spin_unlock(&sbsec->isec_lock);
694out:
bc7e982b 695 mutex_unlock(&sbsec->lock);
1da177e4
LT		 696 return rc;
697}
698
699static inline u16 inode_mode_to_security_class(umode_t mode)
700{
701 switch (mode & S_IFMT) {
702 case S_IFSOCK:
703 return SECCLASS_SOCK_FILE;
704 case S_IFLNK:
705 return SECCLASS_LNK_FILE;
706 case S_IFREG:
707 return SECCLASS_FILE;
708 case S_IFBLK:
709 return SECCLASS_BLK_FILE;
710 case S_IFDIR:
711 return SECCLASS_DIR;
712 case S_IFCHR:
713 return SECCLASS_CHR_FILE;
714 case S_IFIFO:
715 return SECCLASS_FIFO_FILE;
716
717 }
718
719 return SECCLASS_FILE;
720}
721
13402580
JM		 722static inline int default_protocol_stream(int protocol)
723{
724 return (protocol == IPPROTO_IP || protocol == IPPROTO_TCP);
725}
726
727static inline int default_protocol_dgram(int protocol)
728{
729 return (protocol == IPPROTO_IP || protocol == IPPROTO_UDP);
730}
731
1da177e4
LT		 732static inline u16 socket_type_to_security_class(int family, int type, int protocol)
733{
734 switch (family) {
735 case PF_UNIX:
736 switch (type) {
737 case SOCK_STREAM:
738 case SOCK_SEQPACKET:
739 return SECCLASS_UNIX_STREAM_SOCKET;
740 case SOCK_DGRAM:
741 return SECCLASS_UNIX_DGRAM_SOCKET;
742 }
743 break;
744 case PF_INET:
745 case PF_INET6:
746 switch (type) {
747 case SOCK_STREAM:
13402580
JM		 748 if (default_protocol_stream(protocol))
749 return SECCLASS_TCP_SOCKET;
750 else
751 return SECCLASS_RAWIP_SOCKET;
1da177e4 752 case SOCK_DGRAM:
13402580
JM		 753 if (default_protocol_dgram(protocol))
754 return SECCLASS_UDP_SOCKET;
755 else
756 return SECCLASS_RAWIP_SOCKET;
2ee92d46
JM		 757 case SOCK_DCCP:
758 return SECCLASS_DCCP_SOCKET;
13402580 759 default:
1da177e4
LT		 760 return SECCLASS_RAWIP_SOCKET;
761 }
762 break;
763 case PF_NETLINK:
764 switch (protocol) {
765 case NETLINK_ROUTE:
766 return SECCLASS_NETLINK_ROUTE_SOCKET;
767 case NETLINK_FIREWALL:
768 return SECCLASS_NETLINK_FIREWALL_SOCKET;
216efaaa 769 case NETLINK_INET_DIAG:
1da177e4
LT		 770 return SECCLASS_NETLINK_TCPDIAG_SOCKET;
771 case NETLINK_NFLOG:
772 return SECCLASS_NETLINK_NFLOG_SOCKET;
773 case NETLINK_XFRM:
774 return SECCLASS_NETLINK_XFRM_SOCKET;
775 case NETLINK_SELINUX:
776 return SECCLASS_NETLINK_SELINUX_SOCKET;
777 case NETLINK_AUDIT:
778 return SECCLASS_NETLINK_AUDIT_SOCKET;
779 case NETLINK_IP6_FW:
780 return SECCLASS_NETLINK_IP6FW_SOCKET;
781 case NETLINK_DNRTMSG:
782 return SECCLASS_NETLINK_DNRT_SOCKET;
0c9b7942
JM		 783 case NETLINK_KOBJECT_UEVENT:
784 return SECCLASS_NETLINK_KOBJECT_UEVENT_SOCKET;
1da177e4
LT		 785 default:
786 return SECCLASS_NETLINK_SOCKET;
787 }
788 case PF_PACKET:
789 return SECCLASS_PACKET_SOCKET;
790 case PF_KEY:
791 return SECCLASS_KEY_SOCKET;
3e3ff15e
CP		 792 case PF_APPLETALK:
793 return SECCLASS_APPLETALK_SOCKET;
1da177e4
LT		 794 }
795
796 return SECCLASS_SOCKET;
797}
798
799#ifdef CONFIG_PROC_FS
800static int selinux_proc_get_sid(struct proc_dir_entry *de,
801 u16 tclass,
802 u32 *sid)
803{
804 int buflen, rc;
805 char *buffer, *path, *end;
806
807 buffer = (char*)__get_free_page(GFP_KERNEL);
808 if (!buffer)
809 return -ENOMEM;
810
811 buflen = PAGE_SIZE;
812 end = buffer+buflen;
813 *--end = '\0';
814 buflen--;
815 path = end-1;
816 *path = '/';
817 while (de && de != de->parent) {
818 buflen -= de->namelen + 1;
819 if (buflen < 0)
820 break;
821 end -= de->namelen;
822 memcpy(end, de->name, de->namelen);
823 *--end = '/';
824 path = end;
825 de = de->parent;
826 }
827 rc = security_genfs_sid("proc", path, tclass, sid);
828 free_page((unsigned long)buffer);
829 return rc;
830}
831#else
832static int selinux_proc_get_sid(struct proc_dir_entry *de,
833 u16 tclass,
834 u32 *sid)
835{
836 return -EINVAL;
837}
838#endif
839
840/* The inode's security attributes must be initialized before first use. */
841static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dentry)
842{
843 struct superblock_security_struct *sbsec = NULL;
844 struct inode_security_struct *isec = inode->i_security;
845 u32 sid;
846 struct dentry *dentry;
847#define INITCONTEXTLEN 255
848 char *context = NULL;
849 unsigned len = 0;
850 int rc = 0;
1da177e4
LT		 851
852 if (isec->initialized)
853 goto out;
854
23970741 855 mutex_lock(&isec->lock);
1da177e4 856 if (isec->initialized)
23970741 857 goto out_unlock;
1da177e4
LT		 858
859 sbsec = inode->i_sb->s_security;
860 if (!sbsec->initialized) {
861 /* Defer initialization until selinux_complete_init,
862 after the initial policy is loaded and the security
863 server is ready to handle calls. */
864 spin_lock(&sbsec->isec_lock);
865 if (list_empty(&isec->list))
866 list_add(&isec->list, &sbsec->isec_head);
867 spin_unlock(&sbsec->isec_lock);
23970741 868 goto out_unlock;
1da177e4
LT		 869 }
870
871 switch (sbsec->behavior) {
872 case SECURITY_FS_USE_XATTR:
873 if (!inode->i_op->getxattr) {
874 isec->sid = sbsec->def_sid;
875 break;
876 }
877
878 /* Need a dentry, since the xattr API requires one.
879 Life would be simpler if we could just pass the inode. */
880 if (opt_dentry) {
881 /* Called from d_instantiate or d_splice_alias. */
882 dentry = dget(opt_dentry);
883 } else {
884 /* Called from selinux_complete_init, try to find a dentry. */
885 dentry = d_find_alias(inode);
886 }
887 if (!dentry) {
888 printk(KERN_WARNING "%s: no dentry for dev=%s "
889 "ino=%ld\n", __FUNCTION__, inode->i_sb->s_id,
890 inode->i_ino);
23970741 891 goto out_unlock;
1da177e4
LT		 892 }
893
894 len = INITCONTEXTLEN;
895 context = kmalloc(len, GFP_KERNEL);
896 if (!context) {
897 rc = -ENOMEM;
898 dput(dentry);
23970741 899 goto out_unlock;
1da177e4
LT		 900 }
901 rc = inode->i_op->getxattr(dentry, XATTR_NAME_SELINUX,
902 context, len);
903 if (rc == -ERANGE) {
904 /* Need a larger buffer. Query for the right size. */
905 rc = inode->i_op->getxattr(dentry, XATTR_NAME_SELINUX,
906 NULL, 0);
907 if (rc < 0) {
908 dput(dentry);
23970741 909 goto out_unlock;
1da177e4
LT		 910 }
911 kfree(context);
912 len = rc;
913 context = kmalloc(len, GFP_KERNEL);
914 if (!context) {
915 rc = -ENOMEM;
916 dput(dentry);
23970741 917 goto out_unlock;
1da177e4
LT		 918 }
919 rc = inode->i_op->getxattr(dentry,
920 XATTR_NAME_SELINUX,
921 context, len);
922 }
923 dput(dentry);
924 if (rc < 0) {
925 if (rc != -ENODATA) {
926 printk(KERN_WARNING "%s: getxattr returned "
927 "%d for dev=%s ino=%ld\n", __FUNCTION__,
928 -rc, inode->i_sb->s_id, inode->i_ino);
929 kfree(context);
23970741 930 goto out_unlock;
1da177e4
LT		 931 }
932 /* Map ENODATA to the default file SID */
933 sid = sbsec->def_sid;
934 rc = 0;
935 } else {
f5c1d5b2
JM		 936 rc = security_context_to_sid_default(context, rc, &sid,
937 sbsec->def_sid);
1da177e4
LT		 938 if (rc) {
939 printk(KERN_WARNING "%s: context_to_sid(%s) "
940 "returned %d for dev=%s ino=%ld\n",
941 __FUNCTION__, context, -rc,
942 inode->i_sb->s_id, inode->i_ino);
943 kfree(context);
944 /* Leave with the unlabeled SID */
945 rc = 0;
946 break;
947 }
948 }
949 kfree(context);
950 isec->sid = sid;
951 break;
952 case SECURITY_FS_USE_TASK:
953 isec->sid = isec->task_sid;
954 break;
955 case SECURITY_FS_USE_TRANS:
956 /* Default to the fs SID. */
957 isec->sid = sbsec->sid;
958
959 /* Try to obtain a transition SID. */
960 isec->sclass = inode_mode_to_security_class(inode->i_mode);
961 rc = security_transition_sid(isec->task_sid,
962 sbsec->sid,
963 isec->sclass,
964 &sid);
965 if (rc)
23970741 966 goto out_unlock;
1da177e4
LT		 967 isec->sid = sid;
968 break;
c312feb2
EP		 969 case SECURITY_FS_USE_MNTPOINT:
970 isec->sid = sbsec->mntpoint_sid;
971 break;
1da177e4 972 default:
c312feb2 973 /* Default to the fs superblock SID. */
1da177e4
LT		 974 isec->sid = sbsec->sid;
975
976 if (sbsec->proc) {
977 struct proc_inode *proci = PROC_I(inode);
978 if (proci->pde) {
979 isec->sclass = inode_mode_to_security_class(inode->i_mode);
980 rc = selinux_proc_get_sid(proci->pde,
981 isec->sclass,
982 &sid);
983 if (rc)
23970741 984 goto out_unlock;
1da177e4
LT		 985 isec->sid = sid;
986 }
987 }
988 break;
989 }
990
991 isec->initialized = 1;
992
23970741
EP		 993out_unlock:
994 mutex_unlock(&isec->lock);
1da177e4
LT		 995out:
996 if (isec->sclass == SECCLASS_FILE)
997 isec->sclass = inode_mode_to_security_class(inode->i_mode);
1da177e4
LT		 998 return rc;
999}
1000
1001/* Convert a Linux signal to an access vector. */
1002static inline u32 signal_to_av(int sig)
1003{
1004 u32 perm = 0;
1005
1006 switch (sig) {
1007 case SIGCHLD:
1008 /* Commonly granted from child to parent. */
1009 perm = PROCESS__SIGCHLD;
1010 break;
1011 case SIGKILL:
1012 /* Cannot be caught or ignored */
1013 perm = PROCESS__SIGKILL;
1014 break;
1015 case SIGSTOP:
1016 /* Cannot be caught or ignored */
1017 perm = PROCESS__SIGSTOP;
1018 break;
1019 default:
1020 /* All other signals. */
1021 perm = PROCESS__SIGNAL;
1022 break;
1023 }
1024
1025 return perm;
1026}
1027
1028/* Check permission betweeen a pair of tasks, e.g. signal checks,
1029 fork check, ptrace check, etc. */
1030static int task_has_perm(struct task_struct *tsk1,
1031 struct task_struct *tsk2,
1032 u32 perms)
1033{
1034 struct task_security_struct *tsec1, *tsec2;
1035
1036 tsec1 = tsk1->security;
1037 tsec2 = tsk2->security;
1038 return avc_has_perm(tsec1->sid, tsec2->sid,
1039 SECCLASS_PROCESS, perms, NULL);
1040}
1041
1042/* Check whether a task is allowed to use a capability. */
1043static int task_has_capability(struct task_struct *tsk,
1044 int cap)
1045{
1046 struct task_security_struct *tsec;
1047 struct avc_audit_data ad;
1048
1049 tsec = tsk->security;
1050
1051 AVC_AUDIT_DATA_INIT(&ad,CAP);
1052 ad.tsk = tsk;
1053 ad.u.cap = cap;
1054
1055 return avc_has_perm(tsec->sid, tsec->sid,
1056 SECCLASS_CAPABILITY, CAP_TO_MASK(cap), &ad);
1057}
1058
1059/* Check whether a task is allowed to use a system operation. */
1060static int task_has_system(struct task_struct *tsk,
1061 u32 perms)
1062{
1063 struct task_security_struct *tsec;
1064
1065 tsec = tsk->security;
1066
1067 return avc_has_perm(tsec->sid, SECINITSID_KERNEL,
1068 SECCLASS_SYSTEM, perms, NULL);
1069}
1070
1071/* Check whether a task has a particular permission to an inode.
1072 The 'adp' parameter is optional and allows other audit
1073 data to be passed (e.g. the dentry). */
1074static int inode_has_perm(struct task_struct *tsk,
1075 struct inode *inode,
1076 u32 perms,
1077 struct avc_audit_data *adp)
1078{
1079 struct task_security_struct *tsec;
1080 struct inode_security_struct *isec;
1081 struct avc_audit_data ad;
1082
bbaca6c2
SS		 1083 if (unlikely (IS_PRIVATE (inode)))
1084 return 0;
1085
1da177e4
LT		 1086 tsec = tsk->security;
1087 isec = inode->i_security;
1088
1089 if (!adp) {
1090 adp = &ad;
1091 AVC_AUDIT_DATA_INIT(&ad, FS);
1092 ad.u.fs.inode = inode;
1093 }
1094
1095 return avc_has_perm(tsec->sid, isec->sid, isec->sclass, perms, adp);
1096}
1097
1098/* Same as inode_has_perm, but pass explicit audit data containing
1099 the dentry to help the auditing code to more easily generate the
1100 pathname if needed. */
1101static inline int dentry_has_perm(struct task_struct *tsk,
1102 struct vfsmount *mnt,
1103 struct dentry *dentry,
1104 u32 av)
1105{
1106 struct inode *inode = dentry->d_inode;
1107 struct avc_audit_data ad;
1108 AVC_AUDIT_DATA_INIT(&ad,FS);
1109 ad.u.fs.mnt = mnt;
1110 ad.u.fs.dentry = dentry;
1111 return inode_has_perm(tsk, inode, av, &ad);
1112}
1113
1114/* Check whether a task can use an open file descriptor to
1115 access an inode in a given way. Check access to the
1116 descriptor itself, and then use dentry_has_perm to
1117 check a particular permission to the file.
1118 Access to the descriptor is implicitly granted if it
1119 has the same SID as the process. If av is zero, then
1120 access to the file is not checked, e.g. for cases
1121 where only the descriptor is affected like seek. */
858119e1 1122static int file_has_perm(struct task_struct *tsk,
1da177e4
LT		 1123 struct file *file,
1124 u32 av)
1125{
1126 struct task_security_struct *tsec = tsk->security;
1127 struct file_security_struct *fsec = file->f_security;
3d5ff529
JS		 1128 struct vfsmount *mnt = file->f_path.mnt;
1129 struct dentry *dentry = file->f_path.dentry;
1da177e4
LT		 1130 struct inode *inode = dentry->d_inode;
1131 struct avc_audit_data ad;
1132 int rc;
1133
1134 AVC_AUDIT_DATA_INIT(&ad, FS);
1135 ad.u.fs.mnt = mnt;
1136 ad.u.fs.dentry = dentry;
1137
1138 if (tsec->sid != fsec->sid) {
1139 rc = avc_has_perm(tsec->sid, fsec->sid,
1140 SECCLASS_FD,
1141 FD__USE,
1142 &ad);
1143 if (rc)
1144 return rc;
1145 }
1146
1147 /* av is zero if only checking access to the descriptor. */
1148 if (av)
1149 return inode_has_perm(tsk, inode, av, &ad);
1150
1151 return 0;
1152}
1153
1154/* Check whether a task can create a file. */
1155static int may_create(struct inode *dir,
1156 struct dentry *dentry,
1157 u16 tclass)
1158{
1159 struct task_security_struct *tsec;
1160 struct inode_security_struct *dsec;
1161 struct superblock_security_struct *sbsec;
1162 u32 newsid;
1163 struct avc_audit_data ad;
1164 int rc;
1165
1166 tsec = current->security;
1167 dsec = dir->i_security;
1168 sbsec = dir->i_sb->s_security;
1169
1170 AVC_AUDIT_DATA_INIT(&ad, FS);
1171 ad.u.fs.dentry = dentry;
1172
1173 rc = avc_has_perm(tsec->sid, dsec->sid, SECCLASS_DIR,
1174 DIR__ADD_NAME | DIR__SEARCH,
1175 &ad);
1176 if (rc)
1177 return rc;
1178
1179 if (tsec->create_sid && sbsec->behavior != SECURITY_FS_USE_MNTPOINT) {
1180 newsid = tsec->create_sid;
1181 } else {
1182 rc = security_transition_sid(tsec->sid, dsec->sid, tclass,
1183 &newsid);
1184 if (rc)
1185 return rc;
1186 }
1187
1188 rc = avc_has_perm(tsec->sid, newsid, tclass, FILE__CREATE, &ad);
1189 if (rc)
1190 return rc;
1191
1192 return avc_has_perm(newsid, sbsec->sid,
1193 SECCLASS_FILESYSTEM,
1194 FILESYSTEM__ASSOCIATE, &ad);
1195}
1196
4eb582cf
ML		 1197/* Check whether a task can create a key. */
1198static int may_create_key(u32 ksid,
1199 struct task_struct *ctx)
1200{
1201 struct task_security_struct *tsec;
1202
1203 tsec = ctx->security;
1204
1205 return avc_has_perm(tsec->sid, ksid, SECCLASS_KEY, KEY__CREATE, NULL);
1206}
1207
1da177e4
LT		 1208#define MAY_LINK 0
1209#define MAY_UNLINK 1
1210#define MAY_RMDIR 2
1211
1212/* Check whether a task can link, unlink, or rmdir a file/directory. */
1213static int may_link(struct inode *dir,
1214 struct dentry *dentry,
1215 int kind)
1216
1217{
1218 struct task_security_struct *tsec;
1219 struct inode_security_struct *dsec, *isec;
1220 struct avc_audit_data ad;
1221 u32 av;
1222 int rc;
1223
1224 tsec = current->security;
1225 dsec = dir->i_security;
1226 isec = dentry->d_inode->i_security;
1227
1228 AVC_AUDIT_DATA_INIT(&ad, FS);
1229 ad.u.fs.dentry = dentry;
1230
1231 av = DIR__SEARCH;
1232 av |= (kind ? DIR__REMOVE_NAME : DIR__ADD_NAME);
1233 rc = avc_has_perm(tsec->sid, dsec->sid, SECCLASS_DIR, av, &ad);
1234 if (rc)
1235 return rc;
1236
1237 switch (kind) {
1238 case MAY_LINK:
1239 av = FILE__LINK;
1240 break;
1241 case MAY_UNLINK:
1242 av = FILE__UNLINK;
1243 break;
1244 case MAY_RMDIR:
1245 av = DIR__RMDIR;
1246 break;
1247 default:
1248 printk(KERN_WARNING "may_link: unrecognized kind %d\n", kind);
1249 return 0;
1250 }
1251
1252 rc = avc_has_perm(tsec->sid, isec->sid, isec->sclass, av, &ad);
1253 return rc;
1254}
1255
1256static inline int may_rename(struct inode *old_dir,
1257 struct dentry *old_dentry,
1258 struct inode *new_dir,
1259 struct dentry *new_dentry)
1260{
1261 struct task_security_struct *tsec;
1262 struct inode_security_struct *old_dsec, *new_dsec, *old_isec, *new_isec;
1263 struct avc_audit_data ad;
1264 u32 av;
1265 int old_is_dir, new_is_dir;
1266 int rc;
1267
1268 tsec = current->security;
1269 old_dsec = old_dir->i_security;
1270 old_isec = old_dentry->d_inode->i_security;
1271 old_is_dir = S_ISDIR(old_dentry->d_inode->i_mode);
1272 new_dsec = new_dir->i_security;
1273
1274 AVC_AUDIT_DATA_INIT(&ad, FS);
1275
1276 ad.u.fs.dentry = old_dentry;
1277 rc = avc_has_perm(tsec->sid, old_dsec->sid, SECCLASS_DIR,
1278 DIR__REMOVE_NAME | DIR__SEARCH, &ad);
1279 if (rc)
1280 return rc;
1281 rc = avc_has_perm(tsec->sid, old_isec->sid,
1282 old_isec->sclass, FILE__RENAME, &ad);
1283 if (rc)
1284 return rc;
1285 if (old_is_dir && new_dir != old_dir) {
1286 rc = avc_has_perm(tsec->sid, old_isec->sid,
1287 old_isec->sclass, DIR__REPARENT, &ad);
1288 if (rc)
1289 return rc;
1290 }
1291
1292 ad.u.fs.dentry = new_dentry;
1293 av = DIR__ADD_NAME | DIR__SEARCH;
1294 if (new_dentry->d_inode)
1295 av |= DIR__REMOVE_NAME;
1296 rc = avc_has_perm(tsec->sid, new_dsec->sid, SECCLASS_DIR, av, &ad);
1297 if (rc)
1298 return rc;
1299 if (new_dentry->d_inode) {
1300 new_isec = new_dentry->d_inode->i_security;
1301 new_is_dir = S_ISDIR(new_dentry->d_inode->i_mode);
1302 rc = avc_has_perm(tsec->sid, new_isec->sid,
1303 new_isec->sclass,
1304 (new_is_dir ? DIR__RMDIR : FILE__UNLINK), &ad);
1305 if (rc)
1306 return rc;
1307 }
1308
1309 return 0;
1310}
1311
1312/* Check whether a task can perform a filesystem operation. */
1313static int superblock_has_perm(struct task_struct *tsk,
1314 struct super_block *sb,
1315 u32 perms,
1316 struct avc_audit_data *ad)
1317{
1318 struct task_security_struct *tsec;
1319 struct superblock_security_struct *sbsec;
1320
1321 tsec = tsk->security;
1322 sbsec = sb->s_security;
1323 return avc_has_perm(tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM,
1324 perms, ad);
1325}
1326
1327/* Convert a Linux mode and permission mask to an access vector. */
1328static inline u32 file_mask_to_av(int mode, int mask)
1329{
1330 u32 av = 0;
1331
1332 if ((mode & S_IFMT) != S_IFDIR) {
1333 if (mask & MAY_EXEC)
1334 av |= FILE__EXECUTE;
1335 if (mask & MAY_READ)
1336 av |= FILE__READ;
1337
1338 if (mask & MAY_APPEND)
1339 av |= FILE__APPEND;
1340 else if (mask & MAY_WRITE)
1341 av |= FILE__WRITE;
1342
1343 } else {
1344 if (mask & MAY_EXEC)
1345 av |= DIR__SEARCH;
1346 if (mask & MAY_WRITE)
1347 av |= DIR__WRITE;
1348 if (mask & MAY_READ)
1349 av |= DIR__READ;
1350 }
1351
1352 return av;
1353}
1354
1355/* Convert a Linux file to an access vector. */
1356static inline u32 file_to_av(struct file *file)
1357{
1358 u32 av = 0;
1359
1360 if (file->f_mode & FMODE_READ)
1361 av |= FILE__READ;
1362 if (file->f_mode & FMODE_WRITE) {
1363 if (file->f_flags & O_APPEND)
1364 av |= FILE__APPEND;
1365 else
1366 av |= FILE__WRITE;
1367 }
1368
1369 return av;
1370}
1371
1da177e4
LT		 1372/* Hook functions begin here. */
1373
1374static int selinux_ptrace(struct task_struct *parent, struct task_struct *child)
1375{
1376 struct task_security_struct *psec = parent->security;
1377 struct task_security_struct *csec = child->security;
1378 int rc;
1379
1380 rc = secondary_ops->ptrace(parent,child);
1381 if (rc)
1382 return rc;
1383
1384 rc = task_has_perm(parent, child, PROCESS__PTRACE);
1385 /* Save the SID of the tracing process for later use in apply_creds. */
341c2d80 1386 if (!(child->ptrace & PT_PTRACED) && !rc)
1da177e4
LT		 1387 csec->ptrace_sid = psec->sid;
1388 return rc;
1389}
1390
1391static int selinux_capget(struct task_struct *target, kernel_cap_t *effective,
1392 kernel_cap_t *inheritable, kernel_cap_t *permitted)
1393{
1394 int error;
1395
1396 error = task_has_perm(current, target, PROCESS__GETCAP);
1397 if (error)
1398 return error;
1399
1400 return secondary_ops->capget(target, effective, inheritable, permitted);
1401}
1402
1403static int selinux_capset_check(struct task_struct *target, kernel_cap_t *effective,
1404 kernel_cap_t *inheritable, kernel_cap_t *permitted)
1405{
1406 int error;
1407
1408 error = secondary_ops->capset_check(target, effective, inheritable, permitted);
1409 if (error)
1410 return error;
1411
1412 return task_has_perm(current, target, PROCESS__SETCAP);
1413}
1414
1415static void selinux_capset_set(struct task_struct *target, kernel_cap_t *effective,
1416 kernel_cap_t *inheritable, kernel_cap_t *permitted)
1417{
1418 secondary_ops->capset_set(target, effective, inheritable, permitted);
1419}
1420
1421static int selinux_capable(struct task_struct *tsk, int cap)
1422{
1423 int rc;
1424
1425 rc = secondary_ops->capable(tsk, cap);
1426 if (rc)
1427 return rc;
1428
1429 return task_has_capability(tsk,cap);
1430}
1431
3fbfa981
EB		 1432static int selinux_sysctl_get_sid(ctl_table *table, u16 tclass, u32 *sid)
1433{
1434 int buflen, rc;
1435 char *buffer, *path, *end;
1436
1437 rc = -ENOMEM;
1438 buffer = (char*)__get_free_page(GFP_KERNEL);
1439 if (!buffer)
1440 goto out;
1441
1442 buflen = PAGE_SIZE;
1443 end = buffer+buflen;
1444 *--end = '\0';
1445 buflen--;
1446 path = end-1;
1447 *path = '/';
1448 while (table) {
1449 const char *name = table->procname;
1450 size_t namelen = strlen(name);
1451 buflen -= namelen + 1;
1452 if (buflen < 0)
1453 goto out_free;
1454 end -= namelen;
1455 memcpy(end, name, namelen);
1456 *--end = '/';
1457 path = end;
1458 table = table->parent;
1459 }
b599fdfd
EB		 1460 buflen -= 4;
1461 if (buflen < 0)
1462 goto out_free;
1463 end -= 4;
1464 memcpy(end, "/sys", 4);
1465 path = end;
3fbfa981
EB		 1466 rc = security_genfs_sid("proc", path, tclass, sid);
1467out_free:
1468 free_page((unsigned long)buffer);
1469out:
1470 return rc;
1471}
1472
1da177e4
LT		 1473static int selinux_sysctl(ctl_table *table, int op)
1474{
1475 int error = 0;
1476 u32 av;
1477 struct task_security_struct *tsec;
1478 u32 tsid;
1479 int rc;
1480
1481 rc = secondary_ops->sysctl(table, op);
1482 if (rc)
1483 return rc;
1484
1485 tsec = current->security;
1486
3fbfa981
EB		 1487 rc = selinux_sysctl_get_sid(table, (op == 0001) ?
1488 SECCLASS_DIR : SECCLASS_FILE, &tsid);
1da177e4
LT		 1489 if (rc) {
1490 /* Default to the well-defined sysctl SID. */
1491 tsid = SECINITSID_SYSCTL;
1492 }
1493
1494 /* The op values are "defined" in sysctl.c, thereby creating
1495 * a bad coupling between this module and sysctl.c */
1496 if(op == 001) {
1497 error = avc_has_perm(tsec->sid, tsid,
1498 SECCLASS_DIR, DIR__SEARCH, NULL);
1499 } else {
1500 av = 0;
1501 if (op & 004)
1502 av |= FILE__READ;
1503 if (op & 002)
1504 av |= FILE__WRITE;
1505 if (av)
1506 error = avc_has_perm(tsec->sid, tsid,
1507 SECCLASS_FILE, av, NULL);
1508 }
1509
1510 return error;
1511}
1512
1513static int selinux_quotactl(int cmds, int type, int id, struct super_block *sb)
1514{
1515 int rc = 0;
1516
1517 if (!sb)
1518 return 0;
1519
1520 switch (cmds) {
1521 case Q_SYNC:
1522 case Q_QUOTAON:
1523 case Q_QUOTAOFF:
1524 case Q_SETINFO:
1525 case Q_SETQUOTA:
1526 rc = superblock_has_perm(current,
1527 sb,
1528 FILESYSTEM__QUOTAMOD, NULL);
1529 break;
1530 case Q_GETFMT:
1531 case Q_GETINFO:
1532 case Q_GETQUOTA:
1533 rc = superblock_has_perm(current,
1534 sb,
1535 FILESYSTEM__QUOTAGET, NULL);
1536 break;
1537 default:
1538 rc = 0; /* let the kernel handle invalid cmds */
1539 break;
1540 }
1541 return rc;
1542}
1543
1544static int selinux_quota_on(struct dentry *dentry)
1545{
1546 return dentry_has_perm(current, NULL, dentry, FILE__QUOTAON);
1547}
1548
1549static int selinux_syslog(int type)
1550{
1551 int rc;
1552
1553 rc = secondary_ops->syslog(type);
1554 if (rc)
1555 return rc;
1556
1557 switch (type) {
1558 case 3: /* Read last kernel messages */
1559 case 10: /* Return size of the log buffer */
1560 rc = task_has_system(current, SYSTEM__SYSLOG_READ);
1561 break;
1562 case 6: /* Disable logging to console */
1563 case 7: /* Enable logging to console */
1564 case 8: /* Set level of messages printed to console */
1565 rc = task_has_system(current, SYSTEM__SYSLOG_CONSOLE);
1566 break;
1567 case 0: /* Close log */
1568 case 1: /* Open log */
1569 case 2: /* Read from log */
1570 case 4: /* Read/clear last kernel messages */
1571 case 5: /* Clear ring buffer */
1572 default:
1573 rc = task_has_system(current, SYSTEM__SYSLOG_MOD);
1574 break;
1575 }
1576 return rc;
1577}
1578
1579/*
1580 * Check that a process has enough memory to allocate a new virtual
1581 * mapping. 0 means there is enough memory for the allocation to
1582 * succeed and -ENOMEM implies there is not.
1583 *
1584 * Note that secondary_ops->capable and task_has_perm_noaudit return 0
1585 * if the capability is granted, but __vm_enough_memory requires 1 if
1586 * the capability is granted.
1587 *
1588 * Do not audit the selinux permission check, as this is applied to all
1589 * processes that allocate mappings.
1590 */
34b4e4aa 1591static int selinux_vm_enough_memory(struct mm_struct *mm, long pages)
1da177e4
LT		 1592{
1593 int rc, cap_sys_admin = 0;
1594 struct task_security_struct *tsec = current->security;
1595
1596 rc = secondary_ops->capable(current, CAP_SYS_ADMIN);
1597 if (rc == 0)
1598 rc = avc_has_perm_noaudit(tsec->sid, tsec->sid,
2c3c05db
SS		 1599 SECCLASS_CAPABILITY,
1600 CAP_TO_MASK(CAP_SYS_ADMIN),
1601 0,
1602 NULL);
1da177e4
LT		 1603
1604 if (rc == 0)
1605 cap_sys_admin = 1;
1606
34b4e4aa 1607 return __vm_enough_memory(mm, pages, cap_sys_admin);
1da177e4
LT		 1608}
1609
1610/* binprm security operations */
1611
1612static int selinux_bprm_alloc_security(struct linux_binprm *bprm)
1613{
1614 struct bprm_security_struct *bsec;
1615
89d155ef 1616 bsec = kzalloc(sizeof(struct bprm_security_struct), GFP_KERNEL);
1da177e4
LT		 1617 if (!bsec)
1618 return -ENOMEM;
1619
1da177e4
LT		 1620 bsec->bprm = bprm;
1621 bsec->sid = SECINITSID_UNLABELED;
1622 bsec->set = 0;
1623
1624 bprm->security = bsec;
1625 return 0;
1626}
1627
1628static int selinux_bprm_set_security(struct linux_binprm *bprm)
1629{
1630 struct task_security_struct *tsec;
3d5ff529 1631 struct inode *inode = bprm->file->f_path.dentry->d_inode;
1da177e4
LT		 1632 struct inode_security_struct *isec;
1633 struct bprm_security_struct *bsec;
1634 u32 newsid;
1635 struct avc_audit_data ad;
1636 int rc;
1637
1638 rc = secondary_ops->bprm_set_security(bprm);
1639 if (rc)
1640 return rc;
1641
1642 bsec = bprm->security;
1643
1644 if (bsec->set)
1645 return 0;
1646
1647 tsec = current->security;
1648 isec = inode->i_security;
1649
1650 /* Default to the current task SID. */
1651 bsec->sid = tsec->sid;
1652
28eba5bf 1653 /* Reset fs, key, and sock SIDs on execve. */
1da177e4 1654 tsec->create_sid = 0;
28eba5bf 1655 tsec->keycreate_sid = 0;
42c3e03e 1656 tsec->sockcreate_sid = 0;
1da177e4
LT		 1657
1658 if (tsec->exec_sid) {
1659 newsid = tsec->exec_sid;
1660 /* Reset exec SID on execve. */
1661 tsec->exec_sid = 0;
1662 } else {
1663 /* Check for a default transition on this program. */
1664 rc = security_transition_sid(tsec->sid, isec->sid,
1665 SECCLASS_PROCESS, &newsid);
1666 if (rc)
1667 return rc;
1668 }
1669
1670 AVC_AUDIT_DATA_INIT(&ad, FS);
3d5ff529
JS		 1671 ad.u.fs.mnt = bprm->file->f_path.mnt;
1672 ad.u.fs.dentry = bprm->file->f_path.dentry;
1da177e4 1673
3d5ff529 1674 if (bprm->file->f_path.mnt->mnt_flags & MNT_NOSUID)
1da177e4
LT		 1675 newsid = tsec->sid;
1676
1677 if (tsec->sid == newsid) {
1678 rc = avc_has_perm(tsec->sid, isec->sid,
1679 SECCLASS_FILE, FILE__EXECUTE_NO_TRANS, &ad);
1680 if (rc)
1681 return rc;
1682 } else {
1683 /* Check permissions for the transition. */
1684 rc = avc_has_perm(tsec->sid, newsid,
1685 SECCLASS_PROCESS, PROCESS__TRANSITION, &ad);
1686 if (rc)
1687 return rc;
1688
1689 rc = avc_has_perm(newsid, isec->sid,
1690 SECCLASS_FILE, FILE__ENTRYPOINT, &ad);
1691 if (rc)
1692 return rc;
1693
1694 /* Clear any possibly unsafe personality bits on exec: */
1695 current->personality &= ~PER_CLEAR_ON_SETID;
1696
1697 /* Set the security field to the new SID. */
1698 bsec->sid = newsid;
1699 }
1700
1701 bsec->set = 1;
1702 return 0;
1703}
1704
1705static int selinux_bprm_check_security (struct linux_binprm *bprm)
1706{
1707 return secondary_ops->bprm_check_security(bprm);
1708}
1709
1710
1711static int selinux_bprm_secureexec (struct linux_binprm *bprm)
1712{
1713 struct task_security_struct *tsec = current->security;
1714 int atsecure = 0;
1715
1716 if (tsec->osid != tsec->sid) {
1717 /* Enable secure mode for SIDs transitions unless
1718 the noatsecure permission is granted between
1719 the two SIDs, i.e. ahp returns 0. */
1720 atsecure = avc_has_perm(tsec->osid, tsec->sid,
1721 SECCLASS_PROCESS,
1722 PROCESS__NOATSECURE, NULL);
1723 }
1724
1725 return (atsecure || secondary_ops->bprm_secureexec(bprm));
1726}
1727
1728static void selinux_bprm_free_security(struct linux_binprm *bprm)
1729{
9a5f04bf 1730 kfree(bprm->security);
1da177e4 1731 bprm->security = NULL;
1da177e4
LT		 1732}
1733
1734extern struct vfsmount *selinuxfs_mount;
1735extern struct dentry *selinux_null;
1736
1737/* Derived from fs/exec.c:flush_old_files. */
1738static inline void flush_unauthorized_files(struct files_struct * files)
1739{
1740 struct avc_audit_data ad;
1741 struct file *file, *devnull = NULL;
b20c8122 1742 struct tty_struct *tty;
badf1662 1743 struct fdtable *fdt;
1da177e4 1744 long j = -1;
24ec839c 1745 int drop_tty = 0;
1da177e4 1746
b20c8122 1747 mutex_lock(&tty_mutex);
24ec839c 1748 tty = get_current_tty();
1da177e4
LT		 1749 if (tty) {
1750 file_list_lock();
2f512016 1751 file = list_entry(tty->tty_files.next, typeof(*file), f_u.fu_list);
1da177e4
LT		 1752 if (file) {
1753 /* Revalidate access to controlling tty.
1754 Use inode_has_perm on the tty inode directly rather
1755 than using file_has_perm, as this particular open
1756 file may belong to another process and we are only
1757 interested in the inode-based check here. */
3d5ff529 1758 struct inode *inode = file->f_path.dentry->d_inode;
1da177e4
LT		 1759 if (inode_has_perm(current, inode,
1760 FILE__READ | FILE__WRITE, NULL)) {
24ec839c 1761 drop_tty = 1;
1da177e4
LT		 1762 }
1763 }
1764 file_list_unlock();
1765 }
b20c8122 1766 mutex_unlock(&tty_mutex);
98a27ba4
EB		 1767 /* Reset controlling tty. */
1768 if (drop_tty)
1769 no_tty();
1da177e4
LT		 1770
1771 /* Revalidate access to inherited open files. */
1772
1773 AVC_AUDIT_DATA_INIT(&ad,FS);
1774
1775 spin_lock(&files->file_lock);
1776 for (;;) {
1777 unsigned long set, i;
1778 int fd;
1779
1780 j++;
1781 i = j * __NFDBITS;
badf1662 1782 fdt = files_fdtable(files);
bbea9f69 1783 if (i >= fdt->max_fds)
1da177e4 1784 break;
badf1662 1785 set = fdt->open_fds->fds_bits[j];
1da177e4
LT		 1786 if (!set)
1787 continue;
1788 spin_unlock(&files->file_lock);
1789 for ( ; set ; i++,set >>= 1) {
1790 if (set & 1) {
1791 file = fget(i);
1792 if (!file)
1793 continue;
1794 if (file_has_perm(current,
1795 file,
1796 file_to_av(file))) {
1797 sys_close(i);
1798 fd = get_unused_fd();
1799 if (fd != i) {
1800 if (fd >= 0)
1801 put_unused_fd(fd);
1802 fput(file);
1803 continue;
1804 }
1805 if (devnull) {
095975da 1806 get_file(devnull);
1da177e4
LT		 1807 } else {
1808 devnull = dentry_open(dget(selinux_null), mntget(selinuxfs_mount), O_RDWR);
fc5d81e6
AM		 1809 if (IS_ERR(devnull)) {
1810 devnull = NULL;
1da177e4
LT		 1811 put_unused_fd(fd);
1812 fput(file);
1813 continue;
1814 }
1815 }
1816 fd_install(fd, devnull);
1817 }
1818 fput(file);
1819 }
1820 }
1821 spin_lock(&files->file_lock);
1822
1823 }
1824 spin_unlock(&files->file_lock);
1825}
1826
1827static void selinux_bprm_apply_creds(struct linux_binprm *bprm, int unsafe)
1828{
1829 struct task_security_struct *tsec;
1830 struct bprm_security_struct *bsec;
1831 u32 sid;
1832 int rc;
1833
1834 secondary_ops->bprm_apply_creds(bprm, unsafe);
1835
1836 tsec = current->security;
1837
1838 bsec = bprm->security;
1839 sid = bsec->sid;
1840
1841 tsec->osid = tsec->sid;
1842 bsec->unsafe = 0;
1843 if (tsec->sid != sid) {
1844 /* Check for shared state. If not ok, leave SID
1845 unchanged and kill. */
1846 if (unsafe & LSM_UNSAFE_SHARE) {
1847 rc = avc_has_perm(tsec->sid, sid, SECCLASS_PROCESS,
1848 PROCESS__SHARE, NULL);
1849 if (rc) {
1850 bsec->unsafe = 1;
1851 return;
1852 }
1853 }
1854
1855 /* Check for ptracing, and update the task SID if ok.
1856 Otherwise, leave SID unchanged and kill. */
1857 if (unsafe & (LSM_UNSAFE_PTRACE | LSM_UNSAFE_PTRACE_CAP)) {
1858 rc = avc_has_perm(tsec->ptrace_sid, sid,
1859 SECCLASS_PROCESS, PROCESS__PTRACE,
1860 NULL);
1861 if (rc) {
1862 bsec->unsafe = 1;
1863 return;
1864 }
1865 }
1866 tsec->sid = sid;
1867 }
1868}
1869
1870/*
1871 * called after apply_creds without the task lock held
1872 */
1873static void selinux_bprm_post_apply_creds(struct linux_binprm *bprm)
1874{
1875 struct task_security_struct *tsec;
1876 struct rlimit *rlim, *initrlim;
1877 struct itimerval itimer;
1878 struct bprm_security_struct *bsec;
1879 int rc, i;
1880
1881 tsec = current->security;
1882 bsec = bprm->security;
1883
1884 if (bsec->unsafe) {
1885 force_sig_specific(SIGKILL, current);
1886 return;
1887 }
1888 if (tsec->osid == tsec->sid)
1889 return;
1890
1891 /* Close files for which the new task SID is not authorized. */
1892 flush_unauthorized_files(current->files);
1893
1894 /* Check whether the new SID can inherit signal state
1895 from the old SID. If not, clear itimers to avoid
1896 subsequent signal generation and flush and unblock
1897 signals. This must occur _after_ the task SID has
1898 been updated so that any kill done after the flush
1899 will be checked against the new SID. */
1900 rc = avc_has_perm(tsec->osid, tsec->sid, SECCLASS_PROCESS,
1901 PROCESS__SIGINH, NULL);
1902 if (rc) {
1903 memset(&itimer, 0, sizeof itimer);
1904 for (i = 0; i < 3; i++)
1905 do_setitimer(i, &itimer, NULL);
1906 flush_signals(current);
1907 spin_lock_irq(&current->sighand->siglock);
1908 flush_signal_handlers(current, 1);
1909 sigemptyset(&current->blocked);
1910 recalc_sigpending();
1911 spin_unlock_irq(&current->sighand->siglock);
1912 }
1913
4ac212ad
SS		 1914 /* Always clear parent death signal on SID transitions. */
1915 current->pdeath_signal = 0;
1916
1da177e4
LT		 1917 /* Check whether the new SID can inherit resource limits
1918 from the old SID. If not, reset all soft limits to
1919 the lower of the current task's hard limit and the init
1920 task's soft limit. Note that the setting of hard limits
1921 (even to lower them) can be controlled by the setrlimit
1922 check. The inclusion of the init task's soft limit into
1923 the computation is to avoid resetting soft limits higher
1924 than the default soft limit for cases where the default
1925 is lower than the hard limit, e.g. RLIMIT_CORE or
1926 RLIMIT_STACK.*/
1927 rc = avc_has_perm(tsec->osid, tsec->sid, SECCLASS_PROCESS,
1928 PROCESS__RLIMITINH, NULL);
1929 if (rc) {
1930 for (i = 0; i < RLIM_NLIMITS; i++) {
1931 rlim = current->signal->rlim + i;
1932 initrlim = init_task.signal->rlim+i;
1933 rlim->rlim_cur = min(rlim->rlim_max,initrlim->rlim_cur);
1934 }
1935 if (current->signal->rlim[RLIMIT_CPU].rlim_cur != RLIM_INFINITY) {
1936 /*
1937 * This will cause RLIMIT_CPU calculations
1938 * to be refigured.
1939 */
1940 current->it_prof_expires = jiffies_to_cputime(1);
1941 }
1942 }
1943
1944 /* Wake up the parent if it is waiting so that it can
1945 recheck wait permission to the new task SID. */
1946 wake_up_interruptible(&current->parent->signal->wait_chldexit);
1947}
1948
1949/* superblock security operations */
1950
1951static int selinux_sb_alloc_security(struct super_block *sb)
1952{
1953 return superblock_alloc_security(sb);
1954}
1955
1956static void selinux_sb_free_security(struct super_block *sb)
1957{
1958 superblock_free_security(sb);
1959}
1960
1961static inline int match_prefix(char *prefix, int plen, char *option, int olen)
1962{
1963 if (plen > olen)
1964 return 0;
1965
1966 return !memcmp(prefix, option, plen);
1967}
1968
1969static inline int selinux_option(char *option, int len)
1970{
1971 return (match_prefix("context=", sizeof("context=")-1, option, len) ||
1972 match_prefix("fscontext=", sizeof("fscontext=")-1, option, len) ||
0808925e
EP		 1973 match_prefix("defcontext=", sizeof("defcontext=")-1, option, len) ||
1974 match_prefix("rootcontext=", sizeof("rootcontext=")-1, option, len));
1da177e4
LT		 1975}
1976
1977static inline void take_option(char **to, char *from, int *first, int len)
1978{
1979 if (!*first) {
1980 **to = ',';
1981 *to += 1;
3528a953 1982 } else
1da177e4
LT		 1983 *first = 0;
1984 memcpy(*to, from, len);
1985 *to += len;
1986}
1987
3528a953
CO		 1988static inline void take_selinux_option(char **to, char *from, int *first,
1989 int len)
1990{
1991 int current_size = 0;
1992
1993 if (!*first) {
1994 **to = '|';
1995 *to += 1;
1996 }
1997 else
1998 *first = 0;
1999
2000 while (current_size < len) {
2001 if (*from != '"') {
2002 **to = *from;
2003 *to += 1;
2004 }
2005 from += 1;
2006 current_size += 1;
2007 }
2008}
2009
1da177e4
LT		 2010static int selinux_sb_copy_data(struct file_system_type *type, void *orig, void *copy)
2011{
2012 int fnosec, fsec, rc = 0;
2013 char *in_save, *in_curr, *in_end;
2014 char *sec_curr, *nosec_save, *nosec;
3528a953 2015 int open_quote = 0;
1da177e4
LT		 2016
2017 in_curr = orig;
2018 sec_curr = copy;
2019
2020 /* Binary mount data: just copy */
2021 if (type->fs_flags & FS_BINARY_MOUNTDATA) {
2022 copy_page(sec_curr, in_curr);
2023 goto out;
2024 }
2025
2026 nosec = (char *)get_zeroed_page(GFP_KERNEL);
2027 if (!nosec) {
2028 rc = -ENOMEM;
2029 goto out;
2030 }
2031
2032 nosec_save = nosec;
2033 fnosec = fsec = 1;
2034 in_save = in_end = orig;
2035
2036 do {
3528a953
CO		 2037 if (*in_end == '"')
2038 open_quote = !open_quote;
2039 if ((*in_end == ',' && open_quote == 0) ||
2040 *in_end == '\0') {
1da177e4
LT		 2041 int len = in_end - in_curr;
2042
2043 if (selinux_option(in_curr, len))
3528a953 2044 take_selinux_option(&sec_curr, in_curr, &fsec, len);
1da177e4
LT		 2045 else
2046 take_option(&nosec, in_curr, &fnosec, len);
2047
2048 in_curr = in_end + 1;
2049 }
2050 } while (*in_end++);
2051
6931dfc9 2052 strcpy(in_save, nosec_save);
da3caa20 2053 free_page((unsigned long)nosec_save);
1da177e4
LT		 2054out:
2055 return rc;
2056}
2057
2058static int selinux_sb_kern_mount(struct super_block *sb, void *data)
2059{
2060 struct avc_audit_data ad;
2061 int rc;
2062
2063 rc = superblock_doinit(sb, data);
2064 if (rc)
2065 return rc;
2066
2067 AVC_AUDIT_DATA_INIT(&ad,FS);
2068 ad.u.fs.dentry = sb->s_root;
2069 return superblock_has_perm(current, sb, FILESYSTEM__MOUNT, &ad);
2070}
2071
726c3342 2072static int selinux_sb_statfs(struct dentry *dentry)
1da177e4
LT		 2073{
2074 struct avc_audit_data ad;
2075
2076 AVC_AUDIT_DATA_INIT(&ad,FS);
726c3342
DH		 2077 ad.u.fs.dentry = dentry->d_sb->s_root;
2078 return superblock_has_perm(current, dentry->d_sb, FILESYSTEM__GETATTR, &ad);
1da177e4
LT		 2079}
2080
2081static int selinux_mount(char * dev_name,
2082 struct nameidata *nd,
2083 char * type,
2084 unsigned long flags,
2085 void * data)
2086{
2087 int rc;
2088
2089 rc = secondary_ops->sb_mount(dev_name, nd, type, flags, data);
2090 if (rc)
2091 return rc;
2092
2093 if (flags & MS_REMOUNT)
2094 return superblock_has_perm(current, nd->mnt->mnt_sb,
2095 FILESYSTEM__REMOUNT, NULL);
2096 else
2097 return dentry_has_perm(current, nd->mnt, nd->dentry,
2098 FILE__MOUNTON);
2099}
2100
2101static int selinux_umount(struct vfsmount *mnt, int flags)
2102{
2103 int rc;
2104
2105 rc = secondary_ops->sb_umount(mnt, flags);
2106 if (rc)
2107 return rc;
2108
2109 return superblock_has_perm(current,mnt->mnt_sb,
2110 FILESYSTEM__UNMOUNT,NULL);
2111}
2112
2113/* inode security operations */
2114
2115static int selinux_inode_alloc_security(struct inode *inode)
2116{
2117 return inode_alloc_security(inode);
2118}
2119
2120static void selinux_inode_free_security(struct inode *inode)
2121{
2122 inode_free_security(inode);
2123}
2124
5e41ff9e
SS		 2125static int selinux_inode_init_security(struct inode *inode, struct inode *dir,
2126 char **name, void **value,
2127 size_t *len)
2128{
2129 struct task_security_struct *tsec;
2130 struct inode_security_struct *dsec;
2131 struct superblock_security_struct *sbsec;
570bc1c2 2132 u32 newsid, clen;
5e41ff9e 2133 int rc;
570bc1c2 2134 char *namep = NULL, *context;
5e41ff9e
SS		 2135
2136 tsec = current->security;
2137 dsec = dir->i_security;
2138 sbsec = dir->i_sb->s_security;
5e41ff9e
SS		 2139
2140 if (tsec->create_sid && sbsec->behavior != SECURITY_FS_USE_MNTPOINT) {
2141 newsid = tsec->create_sid;
2142 } else {
2143 rc = security_transition_sid(tsec->sid, dsec->sid,
2144 inode_mode_to_security_class(inode->i_mode),
2145 &newsid);
2146 if (rc) {
2147 printk(KERN_WARNING "%s: "
2148 "security_transition_sid failed, rc=%d (dev=%s "
2149 "ino=%ld)\n",
2150 __FUNCTION__,
2151 -rc, inode->i_sb->s_id, inode->i_ino);
2152 return rc;
2153 }
2154 }
2155
296fddf7
EP		 2156 /* Possibly defer initialization to selinux_complete_init. */
2157 if (sbsec->initialized) {
2158 struct inode_security_struct *isec = inode->i_security;
2159 isec->sclass = inode_mode_to_security_class(inode->i_mode);
2160 isec->sid = newsid;
2161 isec->initialized = 1;
2162 }
5e41ff9e 2163
8aad3875 2164 if (!ss_initialized || sbsec->behavior == SECURITY_FS_USE_MNTPOINT)
25a74f3b
SS		 2165 return -EOPNOTSUPP;
2166
570bc1c2
SS		 2167 if (name) {
2168 namep = kstrdup(XATTR_SELINUX_SUFFIX, GFP_KERNEL);
2169 if (!namep)
2170 return -ENOMEM;
2171 *name = namep;
2172 }
5e41ff9e 2173
570bc1c2
SS		 2174 if (value && len) {
2175 rc = security_sid_to_context(newsid, &context, &clen);
2176 if (rc) {
2177 kfree(namep);
2178 return rc;
2179 }
2180 *value = context;
2181 *len = clen;
5e41ff9e 2182 }
5e41ff9e 2183
5e41ff9e
SS		 2184 return 0;
2185}
2186
1da177e4
LT		 2187static int selinux_inode_create(struct inode *dir, struct dentry *dentry, int mask)
2188{
2189 return may_create(dir, dentry, SECCLASS_FILE);
2190}
2191
1da177e4
LT		 2192static int selinux_inode_link(struct dentry *old_dentry, struct inode *dir, struct dentry *new_dentry)
2193{
2194 int rc;
2195
2196 rc = secondary_ops->inode_link(old_dentry,dir,new_dentry);
2197 if (rc)
2198 return rc;
2199 return may_link(dir, old_dentry, MAY_LINK);
2200}
2201
1da177e4
LT		 2202static int selinux_inode_unlink(struct inode *dir, struct dentry *dentry)
2203{
2204 int rc;
2205
2206 rc = secondary_ops->inode_unlink(dir, dentry);
2207 if (rc)
2208 return rc;
2209 return may_link(dir, dentry, MAY_UNLINK);
2210}
2211
2212static int selinux_inode_symlink(struct inode *dir, struct dentry *dentry, const char *name)
2213{
2214 return may_create(dir, dentry, SECCLASS_LNK_FILE);
2215}
2216
1da177e4
LT		 2217static int selinux_inode_mkdir(struct inode *dir, struct dentry *dentry, int mask)
2218{
2219 return may_create(dir, dentry, SECCLASS_DIR);
2220}
2221
1da177e4
LT		 2222static int selinux_inode_rmdir(struct inode *dir, struct dentry *dentry)
2223{
2224 return may_link(dir, dentry, MAY_RMDIR);
2225}
2226
2227static int selinux_inode_mknod(struct inode *dir, struct dentry *dentry, int mode, dev_t dev)
2228{
2229 int rc;
2230
2231 rc = secondary_ops->inode_mknod(dir, dentry, mode, dev);
2232 if (rc)
2233 return rc;
2234
2235 return may_create(dir, dentry, inode_mode_to_security_class(mode));
2236}
2237
1da177e4
LT		 2238static int selinux_inode_rename(struct inode *old_inode, struct dentry *old_dentry,
2239 struct inode *new_inode, struct dentry *new_dentry)
2240{
2241 return may_rename(old_inode, old_dentry, new_inode, new_dentry);
2242}
2243
1da177e4
LT		 2244static int selinux_inode_readlink(struct dentry *dentry)
2245{
2246 return dentry_has_perm(current, NULL, dentry, FILE__READ);
2247}
2248
2249static int selinux_inode_follow_link(struct dentry *dentry, struct nameidata *nameidata)
2250{
2251 int rc;
2252
2253 rc = secondary_ops->inode_follow_link(dentry,nameidata);
2254 if (rc)
2255 return rc;
2256 return dentry_has_perm(current, NULL, dentry, FILE__READ);
2257}
2258
2259static int selinux_inode_permission(struct inode *inode, int mask,
2260 struct nameidata *nd)
2261{
2262 int rc;
2263
2264 rc = secondary_ops->inode_permission(inode, mask, nd);
2265 if (rc)
2266 return rc;
2267
2268 if (!mask) {
2269 /* No permission to check. Existence test. */
2270 return 0;
2271 }
2272
2273 return inode_has_perm(current, inode,
2274 file_mask_to_av(inode->i_mode, mask), NULL);
2275}
2276
2277static int selinux_inode_setattr(struct dentry *dentry, struct iattr *iattr)
2278{
2279 int rc;
2280
2281 rc = secondary_ops->inode_setattr(dentry, iattr);
2282 if (rc)
2283 return rc;
2284
2285 if (iattr->ia_valid & ATTR_FORCE)
2286 return 0;
2287
2288 if (iattr->ia_valid & (ATTR_MODE | ATTR_UID | ATTR_GID |
2289 ATTR_ATIME_SET | ATTR_MTIME_SET))
2290 return dentry_has_perm(current, NULL, dentry, FILE__SETATTR);
2291
2292 return dentry_has_perm(current, NULL, dentry, FILE__WRITE);
2293}
2294
2295static int selinux_inode_getattr(struct vfsmount *mnt, struct dentry *dentry)
2296{
2297 return dentry_has_perm(current, mnt, dentry, FILE__GETATTR);
2298}
2299
2300static int selinux_inode_setxattr(struct dentry *dentry, char *name, void *value, size_t size, int flags)
2301{
2302 struct task_security_struct *tsec = current->security;
2303 struct inode *inode = dentry->d_inode;
2304 struct inode_security_struct *isec = inode->i_security;
2305 struct superblock_security_struct *sbsec;
2306 struct avc_audit_data ad;
2307 u32 newsid;
2308 int rc = 0;
2309
2310 if (strcmp(name, XATTR_NAME_SELINUX)) {
2311 if (!strncmp(name, XATTR_SECURITY_PREFIX,
2312 sizeof XATTR_SECURITY_PREFIX - 1) &&
2313 !capable(CAP_SYS_ADMIN)) {
2314 /* A different attribute in the security namespace.
2315 Restrict to administrator. */
2316 return -EPERM;
2317 }
2318
2319 /* Not an attribute we recognize, so just check the
2320 ordinary setattr permission. */
2321 return dentry_has_perm(current, NULL, dentry, FILE__SETATTR);
2322 }
2323
2324 sbsec = inode->i_sb->s_security;
2325 if (sbsec->behavior == SECURITY_FS_USE_MNTPOINT)
2326 return -EOPNOTSUPP;
2327
3bd858ab 2328 if (!is_owner_or_cap(inode))
1da177e4
LT		 2329 return -EPERM;
2330
2331 AVC_AUDIT_DATA_INIT(&ad,FS);
2332 ad.u.fs.dentry = dentry;
2333
2334 rc = avc_has_perm(tsec->sid, isec->sid, isec->sclass,
2335 FILE__RELABELFROM, &ad);
2336 if (rc)
2337 return rc;
2338
2339 rc = security_context_to_sid(value, size, &newsid);
2340 if (rc)
2341 return rc;
2342
2343 rc = avc_has_perm(tsec->sid, newsid, isec->sclass,
2344 FILE__RELABELTO, &ad);
2345 if (rc)
2346 return rc;
2347
2348 rc = security_validate_transition(isec->sid, newsid, tsec->sid,
2349 isec->sclass);
2350 if (rc)
2351 return rc;
2352
2353 return avc_has_perm(newsid,
2354 sbsec->sid,
2355 SECCLASS_FILESYSTEM,
2356 FILESYSTEM__ASSOCIATE,
2357 &ad);
2358}
2359
2360static void selinux_inode_post_setxattr(struct dentry *dentry, char *name,
2361 void *value, size_t size, int flags)
2362{
2363 struct inode *inode = dentry->d_inode;
2364 struct inode_security_struct *isec = inode->i_security;
2365 u32 newsid;
2366 int rc;
2367
2368 if (strcmp(name, XATTR_NAME_SELINUX)) {
2369 /* Not an attribute we recognize, so nothing to do. */
2370 return;
2371 }
2372
2373 rc = security_context_to_sid(value, size, &newsid);
2374 if (rc) {
2375 printk(KERN_WARNING "%s: unable to obtain SID for context "
2376 "%s, rc=%d\n", __FUNCTION__, (char*)value, -rc);
2377 return;
2378 }
2379
2380 isec->sid = newsid;
2381 return;
2382}
2383
2384static int selinux_inode_getxattr (struct dentry *dentry, char *name)
2385{
1da177e4
LT		 2386 return dentry_has_perm(current, NULL, dentry, FILE__GETATTR);
2387}
2388
2389static int selinux_inode_listxattr (struct dentry *dentry)
2390{
2391 return dentry_has_perm(current, NULL, dentry, FILE__GETATTR);
2392}
2393
2394static int selinux_inode_removexattr (struct dentry *dentry, char *name)
2395{
2396 if (strcmp(name, XATTR_NAME_SELINUX)) {
2397 if (!strncmp(name, XATTR_SECURITY_PREFIX,
2398 sizeof XATTR_SECURITY_PREFIX - 1) &&
2399 !capable(CAP_SYS_ADMIN)) {
2400 /* A different attribute in the security namespace.
2401 Restrict to administrator. */
2402 return -EPERM;
2403 }
2404
2405 /* Not an attribute we recognize, so just check the
2406 ordinary setattr permission. Might want a separate
2407 permission for removexattr. */
2408 return dentry_has_perm(current, NULL, dentry, FILE__SETATTR);
2409 }
2410
2411 /* No one is allowed to remove a SELinux security label.
2412 You can change the label, but all data must be labeled. */
2413 return -EACCES;
2414}
2415
8c8570fb
DK		 2416static const char *selinux_inode_xattr_getsuffix(void)
2417{
2418 return XATTR_SELINUX_SUFFIX;
2419}
2420
d381d8a9
JM		 2421/*
2422 * Copy the in-core inode security context value to the user. If the
2423 * getxattr() prior to this succeeded, check to see if we need to
2424 * canonicalize the value to be finally returned to the user.
2425 *
2426 * Permission check is handled by selinux_inode_getxattr hook.
2427 */
7306a0b9 2428static int selinux_inode_getsecurity(const struct inode *inode, const char *name, void *buffer, size_t size, int err)
1da177e4
LT		 2429{
2430 struct inode_security_struct *isec = inode->i_security;
d381d8a9 2431
8c8570fb
DK		 2432 if (strcmp(name, XATTR_SELINUX_SUFFIX))
2433 return -EOPNOTSUPP;
d381d8a9 2434
8c8570fb 2435 return selinux_getsecurity(isec->sid, buffer, size);
1da177e4
LT		 2436}
2437
2438static int selinux_inode_setsecurity(struct inode *inode, const char *name,
2439 const void *value, size_t size, int flags)
2440{
2441 struct inode_security_struct *isec = inode->i_security;
2442 u32 newsid;
2443 int rc;
2444
2445 if (strcmp(name, XATTR_SELINUX_SUFFIX))
2446 return -EOPNOTSUPP;
2447
2448 if (!value || !size)
2449 return -EACCES;
2450
2451 rc = security_context_to_sid((void*)value, size, &newsid);
2452 if (rc)
2453 return rc;
2454
2455 isec->sid = newsid;
2456 return 0;
2457}
2458
2459static int selinux_inode_listsecurity(struct inode *inode, char *buffer, size_t buffer_size)
2460{
2461 const int len = sizeof(XATTR_NAME_SELINUX);
2462 if (buffer && len <= buffer_size)
2463 memcpy(buffer, XATTR_NAME_SELINUX, len);
2464 return len;
2465}
2466
2467/* file security operations */
2468
788e7dd4 2469static int selinux_revalidate_file_permission(struct file *file, int mask)
1da177e4 2470{
7420ed23 2471 int rc;
3d5ff529 2472 struct inode *inode = file->f_path.dentry->d_inode;
1da177e4
LT		 2473
2474 if (!mask) {
2475 /* No permission to check. Existence test. */
2476 return 0;
2477 }
2478
2479 /* file_mask_to_av won't add FILE__WRITE if MAY_APPEND is set */
2480 if ((file->f_flags & O_APPEND) && (mask & MAY_WRITE))
2481 mask |= MAY_APPEND;
2482
7420ed23
VY		 2483 rc = file_has_perm(current, file,
2484 file_mask_to_av(inode->i_mode, mask));
2485 if (rc)
2486 return rc;
2487
2488 return selinux_netlbl_inode_permission(inode, mask);
1da177e4
LT		 2489}
2490
788e7dd4
YN		 2491static int selinux_file_permission(struct file *file, int mask)
2492{
2493 struct inode *inode = file->f_path.dentry->d_inode;
2494 struct task_security_struct *tsec = current->security;
2495 struct file_security_struct *fsec = file->f_security;
2496 struct inode_security_struct *isec = inode->i_security;
2497
2498 if (!mask) {
2499 /* No permission to check. Existence test. */
2500 return 0;
2501 }
2502
2503 if (tsec->sid == fsec->sid && fsec->isid == isec->sid
2504 && fsec->pseqno == avc_policy_seqno())
2505 return selinux_netlbl_inode_permission(inode, mask);
2506
2507 return selinux_revalidate_file_permission(file, mask);
2508}
2509
1da177e4
LT		 2510static int selinux_file_alloc_security(struct file *file)
2511{
2512 return file_alloc_security(file);
2513}
2514
2515static void selinux_file_free_security(struct file *file)
2516{
2517 file_free_security(file);
2518}
2519
2520static int selinux_file_ioctl(struct file *file, unsigned int cmd,
2521 unsigned long arg)
2522{
2523 int error = 0;
2524
2525 switch (cmd) {
2526 case FIONREAD:
2527 /* fall through */
2528 case FIBMAP:
2529 /* fall through */
2530 case FIGETBSZ:
2531 /* fall through */
2532 case EXT2_IOC_GETFLAGS:
2533 /* fall through */
2534 case EXT2_IOC_GETVERSION:
2535 error = file_has_perm(current, file, FILE__GETATTR);
2536 break;
2537
2538 case EXT2_IOC_SETFLAGS:
2539 /* fall through */
2540 case EXT2_IOC_SETVERSION:
2541 error = file_has_perm(current, file, FILE__SETATTR);
2542 break;
2543
2544 /* sys_ioctl() checks */
2545 case FIONBIO:
2546 /* fall through */
2547 case FIOASYNC:
2548 error = file_has_perm(current, file, 0);
2549 break;
2550
2551 case KDSKBENT:
2552 case KDSKBSENT:
2553 error = task_has_capability(current,CAP_SYS_TTY_CONFIG);
2554 break;
2555
2556 /* default case assumes that the command will go
2557 * to the file's ioctl() function.
2558 */
2559 default:
2560 error = file_has_perm(current, file, FILE__IOCTL);
2561
2562 }
2563 return error;
2564}
2565
2566static int file_map_prot_check(struct file *file, unsigned long prot, int shared)
2567{
2568#ifndef CONFIG_PPC32
2569 if ((prot & PROT_EXEC) && (!file || (!shared && (prot & PROT_WRITE)))) {
2570 /*
2571 * We are making executable an anonymous mapping or a
2572 * private file mapping that will also be writable.
2573 * This has an additional check.
2574 */
2575 int rc = task_has_perm(current, current, PROCESS__EXECMEM);
2576 if (rc)
2577 return rc;
2578 }
2579#endif
2580
2581 if (file) {
2582 /* read access is always possible with a mapping */
2583 u32 av = FILE__READ;
2584
2585 /* write access only matters if the mapping is shared */
2586 if (shared && (prot & PROT_WRITE))
2587 av |= FILE__WRITE;
2588
2589 if (prot & PROT_EXEC)
2590 av |= FILE__EXECUTE;
2591
2592 return file_has_perm(current, file, av);
2593 }
2594 return 0;
2595}
2596
2597static int selinux_file_mmap(struct file *file, unsigned long reqprot,
ed032189
EP		 2598 unsigned long prot, unsigned long flags,
2599 unsigned long addr, unsigned long addr_only)
1da177e4 2600{
ed032189
EP		 2601 int rc = 0;
2602 u32 sid = ((struct task_security_struct*)(current->security))->sid;
1da177e4 2603
ed032189
EP		 2604 if (addr < mmap_min_addr)
2605 rc = avc_has_perm(sid, sid, SECCLASS_MEMPROTECT,
2606 MEMPROTECT__MMAP_ZERO, NULL);
2607 if (rc || addr_only)
1da177e4
LT		 2608 return rc;
2609
2610 if (selinux_checkreqprot)
2611 prot = reqprot;
2612
2613 return file_map_prot_check(file, prot,
2614 (flags & MAP_TYPE) == MAP_SHARED);
2615}
2616
2617static int selinux_file_mprotect(struct vm_area_struct *vma,
2618 unsigned long reqprot,
2619 unsigned long prot)
2620{
2621 int rc;
2622
2623 rc = secondary_ops->file_mprotect(vma, reqprot, prot);
2624 if (rc)
2625 return rc;
2626
2627 if (selinux_checkreqprot)
2628 prot = reqprot;
2629
2630#ifndef CONFIG_PPC32
db4c9641
SS		 2631 if ((prot & PROT_EXEC) && !(vma->vm_flags & VM_EXEC)) {
2632 rc = 0;
2633 if (vma->vm_start >= vma->vm_mm->start_brk &&
2634 vma->vm_end <= vma->vm_mm->brk) {
2635 rc = task_has_perm(current, current,
2636 PROCESS__EXECHEAP);
2637 } else if (!vma->vm_file &&
2638 vma->vm_start <= vma->vm_mm->start_stack &&
2639 vma->vm_end >= vma->vm_mm->start_stack) {
2640 rc = task_has_perm(current, current, PROCESS__EXECSTACK);
2641 } else if (vma->vm_file && vma->anon_vma) {
2642 /*
2643 * We are making executable a file mapping that has
2644 * had some COW done. Since pages might have been
2645 * written, check ability to execute the possibly
2646 * modified content. This typically should only
2647 * occur for text relocations.
2648 */
2649 rc = file_has_perm(current, vma->vm_file,
2650 FILE__EXECMOD);
2651 }