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SELinux: extract the NetLabel SELinux support from the security server
[mirror_ubuntu-bionic-kernel.git] / security / selinux / hooks.c
CommitLineData
1da177e4
LT		 1/*
2 * NSA Security-Enhanced Linux (SELinux) security module
3 *
4 * This file contains the SELinux hook function implementations.
5 *
6 * Authors: Stephen Smalley, <sds@epoch.ncsc.mil>
7 * Chris Vance, <cvance@nai.com>
8 * Wayne Salamon, <wsalamon@nai.com>
9 * James Morris <jmorris@redhat.com>
10 *
11 * Copyright (C) 2001,2002 Networks Associates Technology, Inc.
12 * Copyright (C) 2003 Red Hat, Inc., James Morris <jmorris@redhat.com>
13 * Copyright (C) 2004-2005 Trusted Computer Solutions, Inc.
14 * <dgoeddel@trustedcs.com>
7420ed23
VY		 15 * Copyright (C) 2006 Hewlett-Packard Development Company, L.P.
16 * Paul Moore, <paul.moore@hp.com>
1da177e4
LT		 17 *
18 * This program is free software; you can redistribute it and/or modify
19 * it under the terms of the GNU General Public License version 2,
20 * as published by the Free Software Foundation.
21 */
22
1da177e4
LT		 23#include <linux/module.h>
24#include <linux/init.h>
25#include <linux/kernel.h>
26#include <linux/ptrace.h>
27#include <linux/errno.h>
28#include <linux/sched.h>
29#include <linux/security.h>
30#include <linux/xattr.h>
31#include <linux/capability.h>
32#include <linux/unistd.h>
33#include <linux/mm.h>
34#include <linux/mman.h>
35#include <linux/slab.h>
36#include <linux/pagemap.h>
37#include <linux/swap.h>
38#include <linux/smp_lock.h>
39#include <linux/spinlock.h>
40#include <linux/syscalls.h>
41#include <linux/file.h>
42#include <linux/namei.h>
43#include <linux/mount.h>
44#include <linux/ext2_fs.h>
45#include <linux/proc_fs.h>
46#include <linux/kd.h>
47#include <linux/netfilter_ipv4.h>
48#include <linux/netfilter_ipv6.h>
49#include <linux/tty.h>
50#include <net/icmp.h>
51#include <net/ip.h> /* for sysctl_local_port_range[] */
52#include <net/tcp.h> /* struct or_callable used in sock_rcv_skb */
53#include <asm/uaccess.h>
1da177e4
LT		 54#include <asm/ioctls.h>
55#include <linux/bitops.h>
56#include <linux/interrupt.h>
57#include <linux/netdevice.h> /* for network interface checks */
58#include <linux/netlink.h>
59#include <linux/tcp.h>
60#include <linux/udp.h>
2ee92d46 61#include <linux/dccp.h>
1da177e4
LT		 62#include <linux/quota.h>
63#include <linux/un.h> /* for Unix socket types */
64#include <net/af_unix.h> /* for Unix socket types */
65#include <linux/parser.h>
66#include <linux/nfs_mount.h>
67#include <net/ipv6.h>
68#include <linux/hugetlb.h>
69#include <linux/personality.h>
70#include <linux/sysctl.h>
71#include <linux/audit.h>
6931dfc9 72#include <linux/string.h>
877ce7c1 73#include <linux/selinux.h>
23970741 74#include <linux/mutex.h>
1da177e4
LT		 75
76#include "avc.h"
77#include "objsec.h"
78#include "netif.h"
d28d1e08 79#include "xfrm.h"
7420ed23 80#include "selinux_netlabel.h"
1da177e4
LT		 81
82#define XATTR_SELINUX_SUFFIX "selinux"
83#define XATTR_NAME_SELINUX XATTR_SECURITY_PREFIX XATTR_SELINUX_SUFFIX
84
85extern unsigned int policydb_loaded_version;
86extern int selinux_nlmsg_lookup(u16 sclass, u16 nlmsg_type, u32 *perm);
4e5ab4cb 87extern int selinux_compat_net;
1da177e4
LT		 88
89#ifdef CONFIG_SECURITY_SELINUX_DEVELOP
90int selinux_enforcing = 0;
91
92static int __init enforcing_setup(char *str)
93{
94 selinux_enforcing = simple_strtol(str,NULL,0);
95 return 1;
96}
97__setup("enforcing=", enforcing_setup);
98#endif
99
100#ifdef CONFIG_SECURITY_SELINUX_BOOTPARAM
101int selinux_enabled = CONFIG_SECURITY_SELINUX_BOOTPARAM_VALUE;
102
103static int __init selinux_enabled_setup(char *str)
104{
105 selinux_enabled = simple_strtol(str, NULL, 0);
106 return 1;
107}
108__setup("selinux=", selinux_enabled_setup);
30d55280
SS		 109#else
110int selinux_enabled = 1;
1da177e4
LT		 111#endif
112
113/* Original (dummy) security module. */
114static struct security_operations *original_ops = NULL;
115
116/* Minimal support for a secondary security module,
117 just to allow the use of the dummy or capability modules.
118 The owlsm module can alternatively be used as a secondary
119 module as long as CONFIG_OWLSM_FD is not enabled. */
120static struct security_operations *secondary_ops = NULL;
121
122/* Lists of inode and superblock security structures initialized
123 before the policy was loaded. */
124static LIST_HEAD(superblock_security_head);
125static DEFINE_SPINLOCK(sb_security_lock);
126
e18b890b 127static struct kmem_cache *sel_inode_cache;
7cae7e26 128
8c8570fb
DK		 129/* Return security context for a given sid or just the context
130 length if the buffer is null or length is 0 */
131static int selinux_getsecurity(u32 sid, void *buffer, size_t size)
132{
133 char *context;
134 unsigned len;
135 int rc;
136
137 rc = security_sid_to_context(sid, &context, &len);
138 if (rc)
139 return rc;
140
141 if (!buffer || !size)
142 goto getsecurity_exit;
143
144 if (size < len) {
145 len = -ERANGE;
146 goto getsecurity_exit;
147 }
148 memcpy(buffer, context, len);
149
150getsecurity_exit:
151 kfree(context);
152 return len;
153}
154
1da177e4
LT		 155/* Allocate and free functions for each kind of security blob. */
156
157static int task_alloc_security(struct task_struct *task)
158{
159 struct task_security_struct *tsec;
160
89d155ef 161 tsec = kzalloc(sizeof(struct task_security_struct), GFP_KERNEL);
1da177e4
LT		 162 if (!tsec)
163 return -ENOMEM;
164
1da177e4
LT		 165 tsec->task = task;
166 tsec->osid = tsec->sid = tsec->ptrace_sid = SECINITSID_UNLABELED;
167 task->security = tsec;
168
169 return 0;
170}
171
172static void task_free_security(struct task_struct *task)
173{
174 struct task_security_struct *tsec = task->security;
1da177e4
LT		 175 task->security = NULL;
176 kfree(tsec);
177}
178
179static int inode_alloc_security(struct inode *inode)
180{
181 struct task_security_struct *tsec = current->security;
182 struct inode_security_struct *isec;
183
c3762229 184 isec = kmem_cache_zalloc(sel_inode_cache, GFP_KERNEL);
1da177e4
LT		 185 if (!isec)
186 return -ENOMEM;
187
23970741 188 mutex_init(&isec->lock);
1da177e4 189 INIT_LIST_HEAD(&isec->list);
1da177e4
LT		 190 isec->inode = inode;
191 isec->sid = SECINITSID_UNLABELED;
192 isec->sclass = SECCLASS_FILE;
9ac49d22 193 isec->task_sid = tsec->sid;
1da177e4
LT		 194 inode->i_security = isec;
195
196 return 0;
197}
198
199static void inode_free_security(struct inode *inode)
200{
201 struct inode_security_struct *isec = inode->i_security;
202 struct superblock_security_struct *sbsec = inode->i_sb->s_security;
203
1da177e4
LT		 204 spin_lock(&sbsec->isec_lock);
205 if (!list_empty(&isec->list))
206 list_del_init(&isec->list);
207 spin_unlock(&sbsec->isec_lock);
208
209 inode->i_security = NULL;
7cae7e26 210 kmem_cache_free(sel_inode_cache, isec);
1da177e4
LT		 211}
212
213static int file_alloc_security(struct file *file)
214{
215 struct task_security_struct *tsec = current->security;
216 struct file_security_struct *fsec;
217
26d2a4be 218 fsec = kzalloc(sizeof(struct file_security_struct), GFP_KERNEL);
1da177e4
LT		 219 if (!fsec)
220 return -ENOMEM;
221
1da177e4 222 fsec->file = file;
9ac49d22
SS		 223 fsec->sid = tsec->sid;
224 fsec->fown_sid = tsec->sid;
1da177e4
LT		 225 file->f_security = fsec;
226
227 return 0;
228}
229
230static void file_free_security(struct file *file)
231{
232 struct file_security_struct *fsec = file->f_security;
1da177e4
LT		 233 file->f_security = NULL;
234 kfree(fsec);
235}
236
237static int superblock_alloc_security(struct super_block *sb)
238{
239 struct superblock_security_struct *sbsec;
240
89d155ef 241 sbsec = kzalloc(sizeof(struct superblock_security_struct), GFP_KERNEL);
1da177e4
LT		 242 if (!sbsec)
243 return -ENOMEM;
244
bc7e982b 245 mutex_init(&sbsec->lock);
1da177e4
LT		 246 INIT_LIST_HEAD(&sbsec->list);
247 INIT_LIST_HEAD(&sbsec->isec_head);
248 spin_lock_init(&sbsec->isec_lock);
1da177e4
LT		 249 sbsec->sb = sb;
250 sbsec->sid = SECINITSID_UNLABELED;
251 sbsec->def_sid = SECINITSID_FILE;
c312feb2 252 sbsec->mntpoint_sid = SECINITSID_UNLABELED;
1da177e4
LT		 253 sb->s_security = sbsec;
254
255 return 0;
256}
257
258static void superblock_free_security(struct super_block *sb)
259{
260 struct superblock_security_struct *sbsec = sb->s_security;
261
1da177e4
LT		 262 spin_lock(&sb_security_lock);
263 if (!list_empty(&sbsec->list))
264 list_del_init(&sbsec->list);
265 spin_unlock(&sb_security_lock);
266
267 sb->s_security = NULL;
268 kfree(sbsec);
269}
270
7d877f3b 271static int sk_alloc_security(struct sock *sk, int family, gfp_t priority)
1da177e4
LT		 272{
273 struct sk_security_struct *ssec;
274
89d155ef 275 ssec = kzalloc(sizeof(*ssec), priority);
1da177e4
LT		 276 if (!ssec)
277 return -ENOMEM;
278
1da177e4
LT		 279 ssec->sk = sk;
280 ssec->peer_sid = SECINITSID_UNLABELED;
892c141e 281 ssec->sid = SECINITSID_UNLABELED;
1da177e4
LT		 282 sk->sk_security = ssec;
283
99f59ed0
PM		 284 selinux_netlbl_sk_security_init(ssec, family);
285
1da177e4
LT		 286 return 0;
287}
288
289static void sk_free_security(struct sock *sk)
290{
291 struct sk_security_struct *ssec = sk->sk_security;
292
1da177e4
LT		 293 sk->sk_security = NULL;
294 kfree(ssec);
295}
1da177e4
LT		 296
297/* The security server must be initialized before
298 any labeling or access decisions can be provided. */
299extern int ss_initialized;
300
301/* The file system's label must be initialized prior to use. */
302
303static char *labeling_behaviors[6] = {
304 "uses xattr",
305 "uses transition SIDs",
306 "uses task SIDs",
307 "uses genfs_contexts",
308 "not configured for labeling",
309 "uses mountpoint labeling",
310};
311
312static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dentry);
313
314static inline int inode_doinit(struct inode *inode)
315{
316 return inode_doinit_with_dentry(inode, NULL);
317}
318
319enum {
320 Opt_context = 1,
321 Opt_fscontext = 2,
322 Opt_defcontext = 4,
0808925e 323 Opt_rootcontext = 8,
1da177e4
LT		 324};
325
326static match_table_t tokens = {
327 {Opt_context, "context=%s"},
328 {Opt_fscontext, "fscontext=%s"},
329 {Opt_defcontext, "defcontext=%s"},
0808925e 330 {Opt_rootcontext, "rootcontext=%s"},
1da177e4
LT		 331};
332
333#define SEL_MOUNT_FAIL_MSG "SELinux: duplicate or incompatible mount options\n"
334
c312feb2
EP		 335static int may_context_mount_sb_relabel(u32 sid,
336 struct superblock_security_struct *sbsec,
337 struct task_security_struct *tsec)
338{
339 int rc;
340
341 rc = avc_has_perm(tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM,
342 FILESYSTEM__RELABELFROM, NULL);
343 if (rc)
344 return rc;
345
346 rc = avc_has_perm(tsec->sid, sid, SECCLASS_FILESYSTEM,
347 FILESYSTEM__RELABELTO, NULL);
348 return rc;
349}
350
0808925e
EP		 351static int may_context_mount_inode_relabel(u32 sid,
352 struct superblock_security_struct *sbsec,
353 struct task_security_struct *tsec)
354{
355 int rc;
356 rc = avc_has_perm(tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM,
357 FILESYSTEM__RELABELFROM, NULL);
358 if (rc)
359 return rc;
360
361 rc = avc_has_perm(sid, sbsec->sid, SECCLASS_FILESYSTEM,
362 FILESYSTEM__ASSOCIATE, NULL);
363 return rc;
364}
365
1da177e4
LT		 366static int try_context_mount(struct super_block *sb, void *data)
367{
368 char *context = NULL, *defcontext = NULL;
0808925e 369 char *fscontext = NULL, *rootcontext = NULL;
1da177e4
LT		 370 const char *name;
371 u32 sid;
372 int alloc = 0, rc = 0, seen = 0;
373 struct task_security_struct *tsec = current->security;
374 struct superblock_security_struct *sbsec = sb->s_security;
375
376 if (!data)
377 goto out;
378
379 name = sb->s_type->name;
380
381 if (sb->s_type->fs_flags & FS_BINARY_MOUNTDATA) {
382
383 /* NFS we understand. */
384 if (!strcmp(name, "nfs")) {
385 struct nfs_mount_data *d = data;
386
387 if (d->version < NFS_MOUNT_VERSION)
388 goto out;
389
390 if (d->context[0]) {
391 context = d->context;
392 seen |= Opt_context;
393 }
394 } else
395 goto out;
396
397 } else {
398 /* Standard string-based options. */
399 char *p, *options = data;
400
3528a953 401 while ((p = strsep(&options, "|")) != NULL) {
1da177e4
LT		 402 int token;
403 substring_t args[MAX_OPT_ARGS];
404
405 if (!*p)
406 continue;
407
408 token = match_token(p, tokens, args);
409
410 switch (token) {
411 case Opt_context:
c312feb2 412 if (seen & (Opt_context|Opt_defcontext)) {
1da177e4
LT		 413 rc = -EINVAL;
414 printk(KERN_WARNING SEL_MOUNT_FAIL_MSG);
415 goto out_free;
416 }
417 context = match_strdup(&args[0]);
418 if (!context) {
419 rc = -ENOMEM;
420 goto out_free;
421 }
422 if (!alloc)
423 alloc = 1;
424 seen |= Opt_context;
425 break;
426
427 case Opt_fscontext:
c312feb2 428 if (seen & Opt_fscontext) {
1da177e4
LT		 429 rc = -EINVAL;
430 printk(KERN_WARNING SEL_MOUNT_FAIL_MSG);
431 goto out_free;
432 }
c312feb2
EP		 433 fscontext = match_strdup(&args[0]);
434 if (!fscontext) {
1da177e4
LT		 435 rc = -ENOMEM;
436 goto out_free;
437 }
438 if (!alloc)
439 alloc = 1;
440 seen |= Opt_fscontext;
441 break;
442
0808925e
EP		 443 case Opt_rootcontext:
444 if (seen & Opt_rootcontext) {
445 rc = -EINVAL;
446 printk(KERN_WARNING SEL_MOUNT_FAIL_MSG);
447 goto out_free;
448 }
449 rootcontext = match_strdup(&args[0]);
450 if (!rootcontext) {
451 rc = -ENOMEM;
452 goto out_free;
453 }
454 if (!alloc)
455 alloc = 1;
456 seen |= Opt_rootcontext;
457 break;
458
1da177e4
LT		 459 case Opt_defcontext:
460 if (sbsec->behavior != SECURITY_FS_USE_XATTR) {
461 rc = -EINVAL;
462 printk(KERN_WARNING "SELinux: "
463 "defcontext option is invalid "
464 "for this filesystem type\n");
465 goto out_free;
466 }
467 if (seen & (Opt_context|Opt_defcontext)) {
468 rc = -EINVAL;
469 printk(KERN_WARNING SEL_MOUNT_FAIL_MSG);
470 goto out_free;
471 }
472 defcontext = match_strdup(&args[0]);
473 if (!defcontext) {
474 rc = -ENOMEM;
475 goto out_free;
476 }
477 if (!alloc)
478 alloc = 1;
479 seen |= Opt_defcontext;
480 break;
481
482 default:
483 rc = -EINVAL;
484 printk(KERN_WARNING "SELinux: unknown mount "
485 "option\n");
486 goto out_free;
487
488 }
489 }
490 }
491
492 if (!seen)
493 goto out;
494
c312feb2
EP		 495 /* sets the context of the superblock for the fs being mounted. */
496 if (fscontext) {
497 rc = security_context_to_sid(fscontext, strlen(fscontext), &sid);
1da177e4
LT		 498 if (rc) {
499 printk(KERN_WARNING "SELinux: security_context_to_sid"
500 "(%s) failed for (dev %s, type %s) errno=%d\n",
c312feb2 501 fscontext, sb->s_id, name, rc);
1da177e4
LT		 502 goto out_free;
503 }
504
c312feb2 505 rc = may_context_mount_sb_relabel(sid, sbsec, tsec);
1da177e4
LT		 506 if (rc)
507 goto out_free;
508
c312feb2
EP		 509 sbsec->sid = sid;
510 }
511
512 /*
513 * Switch to using mount point labeling behavior.
514 * sets the label used on all file below the mountpoint, and will set
515 * the superblock context if not already set.
516 */
517 if (context) {
518 rc = security_context_to_sid(context, strlen(context), &sid);
519 if (rc) {
520 printk(KERN_WARNING "SELinux: security_context_to_sid"
521 "(%s) failed for (dev %s, type %s) errno=%d\n",
522 context, sb->s_id, name, rc);
523 goto out_free;
524 }
525
b04ea3ce
EP		 526 if (!fscontext) {
527 rc = may_context_mount_sb_relabel(sid, sbsec, tsec);
528 if (rc)
529 goto out_free;
c312feb2 530 sbsec->sid = sid;
b04ea3ce
EP		 531 } else {
532 rc = may_context_mount_inode_relabel(sid, sbsec, tsec);
533 if (rc)
534 goto out_free;
535 }
c312feb2 536 sbsec->mntpoint_sid = sid;
1da177e4 537
c312feb2 538 sbsec->behavior = SECURITY_FS_USE_MNTPOINT;
1da177e4
LT		 539 }
540
0808925e
EP		 541 if (rootcontext) {
542 struct inode *inode = sb->s_root->d_inode;
543 struct inode_security_struct *isec = inode->i_security;
544 rc = security_context_to_sid(rootcontext, strlen(rootcontext), &sid);
545 if (rc) {
546 printk(KERN_WARNING "SELinux: security_context_to_sid"
547 "(%s) failed for (dev %s, type %s) errno=%d\n",
548 rootcontext, sb->s_id, name, rc);
549 goto out_free;
550 }
551
552 rc = may_context_mount_inode_relabel(sid, sbsec, tsec);
553 if (rc)
554 goto out_free;
555
556 isec->sid = sid;
557 isec->initialized = 1;
558 }
559
1da177e4
LT		 560 if (defcontext) {
561 rc = security_context_to_sid(defcontext, strlen(defcontext), &sid);
562 if (rc) {
563 printk(KERN_WARNING "SELinux: security_context_to_sid"
564 "(%s) failed for (dev %s, type %s) errno=%d\n",
565 defcontext, sb->s_id, name, rc);
566 goto out_free;
567 }
568
569 if (sid == sbsec->def_sid)
570 goto out_free;
571
0808925e 572 rc = may_context_mount_inode_relabel(sid, sbsec, tsec);
1da177e4
LT		 573 if (rc)
574 goto out_free;
575
576 sbsec->def_sid = sid;
577 }
578
579out_free:
580 if (alloc) {
581 kfree(context);
582 kfree(defcontext);
c312feb2 583 kfree(fscontext);
0808925e 584 kfree(rootcontext);
1da177e4
LT		 585 }
586out:
587 return rc;
588}
589
590static int superblock_doinit(struct super_block *sb, void *data)
591{
592 struct superblock_security_struct *sbsec = sb->s_security;
593 struct dentry *root = sb->s_root;
594 struct inode *inode = root->d_inode;
595 int rc = 0;
596
bc7e982b 597 mutex_lock(&sbsec->lock);
1da177e4
LT		 598 if (sbsec->initialized)
599 goto out;
600
601 if (!ss_initialized) {
602 /* Defer initialization until selinux_complete_init,
603 after the initial policy is loaded and the security
604 server is ready to handle calls. */
605 spin_lock(&sb_security_lock);
606 if (list_empty(&sbsec->list))
607 list_add(&sbsec->list, &superblock_security_head);
608 spin_unlock(&sb_security_lock);
609 goto out;
610 }
611
612 /* Determine the labeling behavior to use for this filesystem type. */
613 rc = security_fs_use(sb->s_type->name, &sbsec->behavior, &sbsec->sid);
614 if (rc) {
615 printk(KERN_WARNING "%s: security_fs_use(%s) returned %d\n",
616 __FUNCTION__, sb->s_type->name, rc);
617 goto out;
618 }
619
620 rc = try_context_mount(sb, data);
621 if (rc)
622 goto out;
623
624 if (sbsec->behavior == SECURITY_FS_USE_XATTR) {
625 /* Make sure that the xattr handler exists and that no
626 error other than -ENODATA is returned by getxattr on
627 the root directory. -ENODATA is ok, as this may be
628 the first boot of the SELinux kernel before we have
629 assigned xattr values to the filesystem. */
630 if (!inode->i_op->getxattr) {
631 printk(KERN_WARNING "SELinux: (dev %s, type %s) has no "
632 "xattr support\n", sb->s_id, sb->s_type->name);
633 rc = -EOPNOTSUPP;
634 goto out;
635 }
636 rc = inode->i_op->getxattr(root, XATTR_NAME_SELINUX, NULL, 0);
637 if (rc < 0 && rc != -ENODATA) {
638 if (rc == -EOPNOTSUPP)
639 printk(KERN_WARNING "SELinux: (dev %s, type "
640 "%s) has no security xattr handler\n",
641 sb->s_id, sb->s_type->name);
642 else
643 printk(KERN_WARNING "SELinux: (dev %s, type "
644 "%s) getxattr errno %d\n", sb->s_id,
645 sb->s_type->name, -rc);
646 goto out;
647 }
648 }
649
650 if (strcmp(sb->s_type->name, "proc") == 0)
651 sbsec->proc = 1;
652
653 sbsec->initialized = 1;
654
655 if (sbsec->behavior > ARRAY_SIZE(labeling_behaviors)) {
fadcdb45 656 printk(KERN_ERR "SELinux: initialized (dev %s, type %s), unknown behavior\n",
1da177e4
LT		 657 sb->s_id, sb->s_type->name);
658 }
659 else {
fadcdb45 660 printk(KERN_DEBUG "SELinux: initialized (dev %s, type %s), %s\n",
1da177e4
LT		 661 sb->s_id, sb->s_type->name,
662 labeling_behaviors[sbsec->behavior-1]);
663 }
664
665 /* Initialize the root inode. */
666 rc = inode_doinit_with_dentry(sb->s_root->d_inode, sb->s_root);
667
668 /* Initialize any other inodes associated with the superblock, e.g.
669 inodes created prior to initial policy load or inodes created
670 during get_sb by a pseudo filesystem that directly
671 populates itself. */
672 spin_lock(&sbsec->isec_lock);
673next_inode:
674 if (!list_empty(&sbsec->isec_head)) {
675 struct inode_security_struct *isec =
676 list_entry(sbsec->isec_head.next,
677 struct inode_security_struct, list);
678 struct inode *inode = isec->inode;
679 spin_unlock(&sbsec->isec_lock);
680 inode = igrab(inode);
681 if (inode) {
682 if (!IS_PRIVATE (inode))
683 inode_doinit(inode);
684 iput(inode);
685 }
686 spin_lock(&sbsec->isec_lock);
687 list_del_init(&isec->list);
688 goto next_inode;
689 }
690 spin_unlock(&sbsec->isec_lock);
691out:
bc7e982b 692 mutex_unlock(&sbsec->lock);
1da177e4
LT		 693 return rc;
694}
695
696static inline u16 inode_mode_to_security_class(umode_t mode)
697{
698 switch (mode & S_IFMT) {
699 case S_IFSOCK:
700 return SECCLASS_SOCK_FILE;
701 case S_IFLNK:
702 return SECCLASS_LNK_FILE;
703 case S_IFREG:
704 return SECCLASS_FILE;
705 case S_IFBLK:
706 return SECCLASS_BLK_FILE;
707 case S_IFDIR:
708 return SECCLASS_DIR;
709 case S_IFCHR:
710 return SECCLASS_CHR_FILE;
711 case S_IFIFO:
712 return SECCLASS_FIFO_FILE;
713
714 }
715
716 return SECCLASS_FILE;
717}
718
13402580
JM		 719static inline int default_protocol_stream(int protocol)
720{
721 return (protocol == IPPROTO_IP || protocol == IPPROTO_TCP);
722}
723
724static inline int default_protocol_dgram(int protocol)
725{
726 return (protocol == IPPROTO_IP || protocol == IPPROTO_UDP);
727}
728
1da177e4
LT		 729static inline u16 socket_type_to_security_class(int family, int type, int protocol)
730{
731 switch (family) {
732 case PF_UNIX:
733 switch (type) {
734 case SOCK_STREAM:
735 case SOCK_SEQPACKET:
736 return SECCLASS_UNIX_STREAM_SOCKET;
737 case SOCK_DGRAM:
738 return SECCLASS_UNIX_DGRAM_SOCKET;
739 }
740 break;
741 case PF_INET:
742 case PF_INET6:
743 switch (type) {
744 case SOCK_STREAM:
13402580
JM		 745 if (default_protocol_stream(protocol))
746 return SECCLASS_TCP_SOCKET;
747 else
748 return SECCLASS_RAWIP_SOCKET;
1da177e4 749 case SOCK_DGRAM:
13402580
JM		 750 if (default_protocol_dgram(protocol))
751 return SECCLASS_UDP_SOCKET;
752 else
753 return SECCLASS_RAWIP_SOCKET;
2ee92d46
JM		 754 case SOCK_DCCP:
755 return SECCLASS_DCCP_SOCKET;
13402580 756 default:
1da177e4
LT		 757 return SECCLASS_RAWIP_SOCKET;
758 }
759 break;
760 case PF_NETLINK:
761 switch (protocol) {
762 case NETLINK_ROUTE:
763 return SECCLASS_NETLINK_ROUTE_SOCKET;
764 case NETLINK_FIREWALL:
765 return SECCLASS_NETLINK_FIREWALL_SOCKET;
216efaaa 766 case NETLINK_INET_DIAG:
1da177e4
LT		 767 return SECCLASS_NETLINK_TCPDIAG_SOCKET;
768 case NETLINK_NFLOG:
769 return SECCLASS_NETLINK_NFLOG_SOCKET;
770 case NETLINK_XFRM:
771 return SECCLASS_NETLINK_XFRM_SOCKET;
772 case NETLINK_SELINUX:
773 return SECCLASS_NETLINK_SELINUX_SOCKET;
774 case NETLINK_AUDIT:
775 return SECCLASS_NETLINK_AUDIT_SOCKET;
776 case NETLINK_IP6_FW:
777 return SECCLASS_NETLINK_IP6FW_SOCKET;
778 case NETLINK_DNRTMSG:
779 return SECCLASS_NETLINK_DNRT_SOCKET;
0c9b7942
JM		 780 case NETLINK_KOBJECT_UEVENT:
781 return SECCLASS_NETLINK_KOBJECT_UEVENT_SOCKET;
1da177e4
LT		 782 default:
783 return SECCLASS_NETLINK_SOCKET;
784 }
785 case PF_PACKET:
786 return SECCLASS_PACKET_SOCKET;
787 case PF_KEY:
788 return SECCLASS_KEY_SOCKET;
3e3ff15e
CP		 789 case PF_APPLETALK:
790 return SECCLASS_APPLETALK_SOCKET;
1da177e4
LT		 791 }
792
793 return SECCLASS_SOCKET;
794}
795
796#ifdef CONFIG_PROC_FS
797static int selinux_proc_get_sid(struct proc_dir_entry *de,
798 u16 tclass,
799 u32 *sid)
800{
801 int buflen, rc;
802 char *buffer, *path, *end;
803
804 buffer = (char*)__get_free_page(GFP_KERNEL);
805 if (!buffer)
806 return -ENOMEM;
807
808 buflen = PAGE_SIZE;
809 end = buffer+buflen;
810 *--end = '\0';
811 buflen--;
812 path = end-1;
813 *path = '/';
814 while (de && de != de->parent) {
815 buflen -= de->namelen + 1;
816 if (buflen < 0)
817 break;
818 end -= de->namelen;
819 memcpy(end, de->name, de->namelen);
820 *--end = '/';
821 path = end;
822 de = de->parent;
823 }
824 rc = security_genfs_sid("proc", path, tclass, sid);
825 free_page((unsigned long)buffer);
826 return rc;
827}
828#else
829static int selinux_proc_get_sid(struct proc_dir_entry *de,
830 u16 tclass,
831 u32 *sid)
832{
833 return -EINVAL;
834}
835#endif
836
837/* The inode's security attributes must be initialized before first use. */
838static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dentry)
839{
840 struct superblock_security_struct *sbsec = NULL;
841 struct inode_security_struct *isec = inode->i_security;
842 u32 sid;
843 struct dentry *dentry;
844#define INITCONTEXTLEN 255
845 char *context = NULL;
846 unsigned len = 0;
847 int rc = 0;
1da177e4
LT		 848
849 if (isec->initialized)
850 goto out;
851
23970741 852 mutex_lock(&isec->lock);
1da177e4 853 if (isec->initialized)
23970741 854 goto out_unlock;
1da177e4
LT		 855
856 sbsec = inode->i_sb->s_security;
857 if (!sbsec->initialized) {
858 /* Defer initialization until selinux_complete_init,
859 after the initial policy is loaded and the security
860 server is ready to handle calls. */
861 spin_lock(&sbsec->isec_lock);
862 if (list_empty(&isec->list))
863 list_add(&isec->list, &sbsec->isec_head);
864 spin_unlock(&sbsec->isec_lock);
23970741 865 goto out_unlock;
1da177e4
LT		 866 }
867
868 switch (sbsec->behavior) {
869 case SECURITY_FS_USE_XATTR:
870 if (!inode->i_op->getxattr) {
871 isec->sid = sbsec->def_sid;
872 break;
873 }
874
875 /* Need a dentry, since the xattr API requires one.
876 Life would be simpler if we could just pass the inode. */
877 if (opt_dentry) {
878 /* Called from d_instantiate or d_splice_alias. */
879 dentry = dget(opt_dentry);
880 } else {
881 /* Called from selinux_complete_init, try to find a dentry. */
882 dentry = d_find_alias(inode);
883 }
884 if (!dentry) {
885 printk(KERN_WARNING "%s: no dentry for dev=%s "
886 "ino=%ld\n", __FUNCTION__, inode->i_sb->s_id,
887 inode->i_ino);
23970741 888 goto out_unlock;
1da177e4
LT		 889 }
890
891 len = INITCONTEXTLEN;
892 context = kmalloc(len, GFP_KERNEL);
893 if (!context) {
894 rc = -ENOMEM;
895 dput(dentry);
23970741 896 goto out_unlock;
1da177e4
LT		 897 }
898 rc = inode->i_op->getxattr(dentry, XATTR_NAME_SELINUX,
899 context, len);
900 if (rc == -ERANGE) {
901 /* Need a larger buffer. Query for the right size. */
902 rc = inode->i_op->getxattr(dentry, XATTR_NAME_SELINUX,
903 NULL, 0);
904 if (rc < 0) {
905 dput(dentry);
23970741 906 goto out_unlock;
1da177e4
LT		 907 }
908 kfree(context);
909 len = rc;
910 context = kmalloc(len, GFP_KERNEL);
911 if (!context) {
912 rc = -ENOMEM;
913 dput(dentry);
23970741 914 goto out_unlock;
1da177e4
LT		 915 }
916 rc = inode->i_op->getxattr(dentry,
917 XATTR_NAME_SELINUX,
918 context, len);
919 }
920 dput(dentry);
921 if (rc < 0) {
922 if (rc != -ENODATA) {
923 printk(KERN_WARNING "%s: getxattr returned "
924 "%d for dev=%s ino=%ld\n", __FUNCTION__,
925 -rc, inode->i_sb->s_id, inode->i_ino);
926 kfree(context);
23970741 927 goto out_unlock;
1da177e4
LT		 928 }
929 /* Map ENODATA to the default file SID */
930 sid = sbsec->def_sid;
931 rc = 0;
932 } else {
f5c1d5b2
JM		 933 rc = security_context_to_sid_default(context, rc, &sid,
934 sbsec->def_sid);
1da177e4
LT		 935 if (rc) {
936 printk(KERN_WARNING "%s: context_to_sid(%s) "
937 "returned %d for dev=%s ino=%ld\n",
938 __FUNCTION__, context, -rc,
939 inode->i_sb->s_id, inode->i_ino);
940 kfree(context);
941 /* Leave with the unlabeled SID */
942 rc = 0;
943 break;
944 }
945 }
946 kfree(context);
947 isec->sid = sid;
948 break;
949 case SECURITY_FS_USE_TASK:
950 isec->sid = isec->task_sid;
951 break;
952 case SECURITY_FS_USE_TRANS:
953 /* Default to the fs SID. */
954 isec->sid = sbsec->sid;
955
956 /* Try to obtain a transition SID. */
957 isec->sclass = inode_mode_to_security_class(inode->i_mode);
958 rc = security_transition_sid(isec->task_sid,
959 sbsec->sid,
960 isec->sclass,
961 &sid);
962 if (rc)
23970741 963 goto out_unlock;
1da177e4
LT		 964 isec->sid = sid;
965 break;
c312feb2
EP		 966 case SECURITY_FS_USE_MNTPOINT:
967 isec->sid = sbsec->mntpoint_sid;
968 break;
1da177e4 969 default:
c312feb2 970 /* Default to the fs superblock SID. */
1da177e4
LT		 971 isec->sid = sbsec->sid;
972
973 if (sbsec->proc) {
974 struct proc_inode *proci = PROC_I(inode);
975 if (proci->pde) {
976 isec->sclass = inode_mode_to_security_class(inode->i_mode);
977 rc = selinux_proc_get_sid(proci->pde,
978 isec->sclass,
979 &sid);
980 if (rc)
23970741 981 goto out_unlock;
1da177e4
LT		 982 isec->sid = sid;
983 }
984 }
985 break;
986 }
987
988 isec->initialized = 1;
989
23970741
EP		 990out_unlock:
991 mutex_unlock(&isec->lock);
1da177e4
LT		 992out:
993 if (isec->sclass == SECCLASS_FILE)
994 isec->sclass = inode_mode_to_security_class(inode->i_mode);
1da177e4
LT		 995 return rc;
996}
997
998/* Convert a Linux signal to an access vector. */
999static inline u32 signal_to_av(int sig)
1000{
1001 u32 perm = 0;
1002
1003 switch (sig) {
1004 case SIGCHLD:
1005 /* Commonly granted from child to parent. */
1006 perm = PROCESS__SIGCHLD;
1007 break;
1008 case SIGKILL:
1009 /* Cannot be caught or ignored */
1010 perm = PROCESS__SIGKILL;
1011 break;
1012 case SIGSTOP:
1013 /* Cannot be caught or ignored */
1014 perm = PROCESS__SIGSTOP;
1015 break;
1016 default:
1017 /* All other signals. */
1018 perm = PROCESS__SIGNAL;
1019 break;
1020 }
1021
1022 return perm;
1023}
1024
1025/* Check permission betweeen a pair of tasks, e.g. signal checks,
1026 fork check, ptrace check, etc. */
1027static int task_has_perm(struct task_struct *tsk1,
1028 struct task_struct *tsk2,
1029 u32 perms)
1030{
1031 struct task_security_struct *tsec1, *tsec2;
1032
1033 tsec1 = tsk1->security;
1034 tsec2 = tsk2->security;
1035 return avc_has_perm(tsec1->sid, tsec2->sid,
1036 SECCLASS_PROCESS, perms, NULL);
1037}
1038
1039/* Check whether a task is allowed to use a capability. */
1040static int task_has_capability(struct task_struct *tsk,
1041 int cap)
1042{
1043 struct task_security_struct *tsec;
1044 struct avc_audit_data ad;
1045
1046 tsec = tsk->security;
1047
1048 AVC_AUDIT_DATA_INIT(&ad,CAP);
1049 ad.tsk = tsk;
1050 ad.u.cap = cap;
1051
1052 return avc_has_perm(tsec->sid, tsec->sid,
1053 SECCLASS_CAPABILITY, CAP_TO_MASK(cap), &ad);
1054}
1055
1056/* Check whether a task is allowed to use a system operation. */
1057static int task_has_system(struct task_struct *tsk,
1058 u32 perms)
1059{
1060 struct task_security_struct *tsec;
1061
1062 tsec = tsk->security;
1063
1064 return avc_has_perm(tsec->sid, SECINITSID_KERNEL,
1065 SECCLASS_SYSTEM, perms, NULL);
1066}
1067
1068/* Check whether a task has a particular permission to an inode.
1069 The 'adp' parameter is optional and allows other audit
1070 data to be passed (e.g. the dentry). */
1071static int inode_has_perm(struct task_struct *tsk,
1072 struct inode *inode,
1073 u32 perms,
1074 struct avc_audit_data *adp)
1075{
1076 struct task_security_struct *tsec;
1077 struct inode_security_struct *isec;
1078 struct avc_audit_data ad;
1079
bbaca6c2
SS		 1080 if (unlikely (IS_PRIVATE (inode)))
1081 return 0;
1082
1da177e4
LT		 1083 tsec = tsk->security;
1084 isec = inode->i_security;
1085
1086 if (!adp) {
1087 adp = &ad;
1088 AVC_AUDIT_DATA_INIT(&ad, FS);
1089 ad.u.fs.inode = inode;
1090 }
1091
1092 return avc_has_perm(tsec->sid, isec->sid, isec->sclass, perms, adp);
1093}
1094
1095/* Same as inode_has_perm, but pass explicit audit data containing
1096 the dentry to help the auditing code to more easily generate the
1097 pathname if needed. */
1098static inline int dentry_has_perm(struct task_struct *tsk,
1099 struct vfsmount *mnt,
1100 struct dentry *dentry,
1101 u32 av)
1102{
1103 struct inode *inode = dentry->d_inode;
1104 struct avc_audit_data ad;
1105 AVC_AUDIT_DATA_INIT(&ad,FS);
1106 ad.u.fs.mnt = mnt;
1107 ad.u.fs.dentry = dentry;
1108 return inode_has_perm(tsk, inode, av, &ad);
1109}
1110
1111/* Check whether a task can use an open file descriptor to
1112 access an inode in a given way. Check access to the
1113 descriptor itself, and then use dentry_has_perm to
1114 check a particular permission to the file.
1115 Access to the descriptor is implicitly granted if it
1116 has the same SID as the process. If av is zero, then
1117 access to the file is not checked, e.g. for cases
1118 where only the descriptor is affected like seek. */
858119e1 1119static int file_has_perm(struct task_struct *tsk,
1da177e4
LT		 1120 struct file *file,
1121 u32 av)
1122{
1123 struct task_security_struct *tsec = tsk->security;
1124 struct file_security_struct *fsec = file->f_security;
3d5ff529
JS		 1125 struct vfsmount *mnt = file->f_path.mnt;
1126 struct dentry *dentry = file->f_path.dentry;
1da177e4
LT		 1127 struct inode *inode = dentry->d_inode;
1128 struct avc_audit_data ad;
1129 int rc;
1130
1131 AVC_AUDIT_DATA_INIT(&ad, FS);
1132 ad.u.fs.mnt = mnt;
1133 ad.u.fs.dentry = dentry;
1134
1135 if (tsec->sid != fsec->sid) {
1136 rc = avc_has_perm(tsec->sid, fsec->sid,
1137 SECCLASS_FD,
1138 FD__USE,
1139 &ad);
1140 if (rc)
1141 return rc;
1142 }
1143
1144 /* av is zero if only checking access to the descriptor. */
1145 if (av)
1146 return inode_has_perm(tsk, inode, av, &ad);
1147
1148 return 0;
1149}
1150
1151/* Check whether a task can create a file. */
1152static int may_create(struct inode *dir,
1153 struct dentry *dentry,
1154 u16 tclass)
1155{
1156 struct task_security_struct *tsec;
1157 struct inode_security_struct *dsec;
1158 struct superblock_security_struct *sbsec;
1159 u32 newsid;
1160 struct avc_audit_data ad;
1161 int rc;
1162
1163 tsec = current->security;
1164 dsec = dir->i_security;
1165 sbsec = dir->i_sb->s_security;
1166
1167 AVC_AUDIT_DATA_INIT(&ad, FS);
1168 ad.u.fs.dentry = dentry;
1169
1170 rc = avc_has_perm(tsec->sid, dsec->sid, SECCLASS_DIR,
1171 DIR__ADD_NAME | DIR__SEARCH,
1172 &ad);
1173 if (rc)
1174 return rc;
1175
1176 if (tsec->create_sid && sbsec->behavior != SECURITY_FS_USE_MNTPOINT) {
1177 newsid = tsec->create_sid;
1178 } else {
1179 rc = security_transition_sid(tsec->sid, dsec->sid, tclass,
1180 &newsid);
1181 if (rc)
1182 return rc;
1183 }
1184
1185 rc = avc_has_perm(tsec->sid, newsid, tclass, FILE__CREATE, &ad);
1186 if (rc)
1187 return rc;
1188
1189 return avc_has_perm(newsid, sbsec->sid,
1190 SECCLASS_FILESYSTEM,
1191 FILESYSTEM__ASSOCIATE, &ad);
1192}
1193
4eb582cf
ML		 1194/* Check whether a task can create a key. */
1195static int may_create_key(u32 ksid,
1196 struct task_struct *ctx)
1197{
1198 struct task_security_struct *tsec;
1199
1200 tsec = ctx->security;
1201
1202 return avc_has_perm(tsec->sid, ksid, SECCLASS_KEY, KEY__CREATE, NULL);
1203}
1204
1da177e4
LT		 1205#define MAY_LINK 0
1206#define MAY_UNLINK 1
1207#define MAY_RMDIR 2
1208
1209/* Check whether a task can link, unlink, or rmdir a file/directory. */
1210static int may_link(struct inode *dir,
1211 struct dentry *dentry,
1212 int kind)
1213
1214{
1215 struct task_security_struct *tsec;
1216 struct inode_security_struct *dsec, *isec;
1217 struct avc_audit_data ad;
1218 u32 av;
1219 int rc;
1220
1221 tsec = current->security;
1222 dsec = dir->i_security;
1223 isec = dentry->d_inode->i_security;
1224
1225 AVC_AUDIT_DATA_INIT(&ad, FS);
1226 ad.u.fs.dentry = dentry;
1227
1228 av = DIR__SEARCH;
1229 av |= (kind ? DIR__REMOVE_NAME : DIR__ADD_NAME);
1230 rc = avc_has_perm(tsec->sid, dsec->sid, SECCLASS_DIR, av, &ad);
1231 if (rc)
1232 return rc;
1233
1234 switch (kind) {
1235 case MAY_LINK:
1236 av = FILE__LINK;
1237 break;
1238 case MAY_UNLINK:
1239 av = FILE__UNLINK;
1240 break;
1241 case MAY_RMDIR:
1242 av = DIR__RMDIR;
1243 break;
1244 default:
1245 printk(KERN_WARNING "may_link: unrecognized kind %d\n", kind);
1246 return 0;
1247 }
1248
1249 rc = avc_has_perm(tsec->sid, isec->sid, isec->sclass, av, &ad);
1250 return rc;
1251}
1252
1253static inline int may_rename(struct inode *old_dir,
1254 struct dentry *old_dentry,
1255 struct inode *new_dir,
1256 struct dentry *new_dentry)
1257{
1258 struct task_security_struct *tsec;
1259 struct inode_security_struct *old_dsec, *new_dsec, *old_isec, *new_isec;
1260 struct avc_audit_data ad;
1261 u32 av;
1262 int old_is_dir, new_is_dir;
1263 int rc;
1264
1265 tsec = current->security;
1266 old_dsec = old_dir->i_security;
1267 old_isec = old_dentry->d_inode->i_security;
1268 old_is_dir = S_ISDIR(old_dentry->d_inode->i_mode);
1269 new_dsec = new_dir->i_security;
1270
1271 AVC_AUDIT_DATA_INIT(&ad, FS);
1272
1273 ad.u.fs.dentry = old_dentry;
1274 rc = avc_has_perm(tsec->sid, old_dsec->sid, SECCLASS_DIR,
1275 DIR__REMOVE_NAME | DIR__SEARCH, &ad);
1276 if (rc)
1277 return rc;
1278 rc = avc_has_perm(tsec->sid, old_isec->sid,
1279 old_isec->sclass, FILE__RENAME, &ad);
1280 if (rc)
1281 return rc;
1282 if (old_is_dir && new_dir != old_dir) {
1283 rc = avc_has_perm(tsec->sid, old_isec->sid,
1284 old_isec->sclass, DIR__REPARENT, &ad);
1285 if (rc)
1286 return rc;
1287 }
1288
1289 ad.u.fs.dentry = new_dentry;
1290 av = DIR__ADD_NAME | DIR__SEARCH;
1291 if (new_dentry->d_inode)
1292 av |= DIR__REMOVE_NAME;
1293 rc = avc_has_perm(tsec->sid, new_dsec->sid, SECCLASS_DIR, av, &ad);
1294 if (rc)
1295 return rc;
1296 if (new_dentry->d_inode) {
1297 new_isec = new_dentry->d_inode->i_security;
1298 new_is_dir = S_ISDIR(new_dentry->d_inode->i_mode);
1299 rc = avc_has_perm(tsec->sid, new_isec->sid,
1300 new_isec->sclass,
1301 (new_is_dir ? DIR__RMDIR : FILE__UNLINK), &ad);
1302 if (rc)
1303 return rc;
1304 }
1305
1306 return 0;
1307}
1308
1309/* Check whether a task can perform a filesystem operation. */
1310static int superblock_has_perm(struct task_struct *tsk,
1311 struct super_block *sb,
1312 u32 perms,
1313 struct avc_audit_data *ad)
1314{
1315 struct task_security_struct *tsec;
1316 struct superblock_security_struct *sbsec;
1317
1318 tsec = tsk->security;
1319 sbsec = sb->s_security;
1320 return avc_has_perm(tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM,
1321 perms, ad);
1322}
1323
1324/* Convert a Linux mode and permission mask to an access vector. */
1325static inline u32 file_mask_to_av(int mode, int mask)
1326{
1327 u32 av = 0;
1328
1329 if ((mode & S_IFMT) != S_IFDIR) {
1330 if (mask & MAY_EXEC)
1331 av |= FILE__EXECUTE;
1332 if (mask & MAY_READ)
1333 av |= FILE__READ;
1334
1335 if (mask & MAY_APPEND)
1336 av |= FILE__APPEND;
1337 else if (mask & MAY_WRITE)
1338 av |= FILE__WRITE;
1339
1340 } else {
1341 if (mask & MAY_EXEC)
1342 av |= DIR__SEARCH;
1343 if (mask & MAY_WRITE)
1344 av |= DIR__WRITE;
1345 if (mask & MAY_READ)
1346 av |= DIR__READ;
1347 }
1348
1349 return av;
1350}
1351
1352/* Convert a Linux file to an access vector. */
1353static inline u32 file_to_av(struct file *file)
1354{
1355 u32 av = 0;
1356
1357 if (file->f_mode & FMODE_READ)
1358 av |= FILE__READ;
1359 if (file->f_mode & FMODE_WRITE) {
1360 if (file->f_flags & O_APPEND)
1361 av |= FILE__APPEND;
1362 else
1363 av |= FILE__WRITE;
1364 }
1365
1366 return av;
1367}
1368
1da177e4
LT		 1369/* Hook functions begin here. */
1370
1371static int selinux_ptrace(struct task_struct *parent, struct task_struct *child)
1372{
1373 struct task_security_struct *psec = parent->security;
1374 struct task_security_struct *csec = child->security;
1375 int rc;
1376
1377 rc = secondary_ops->ptrace(parent,child);
1378 if (rc)
1379 return rc;
1380
1381 rc = task_has_perm(parent, child, PROCESS__PTRACE);
1382 /* Save the SID of the tracing process for later use in apply_creds. */
341c2d80 1383 if (!(child->ptrace & PT_PTRACED) && !rc)
1da177e4
LT		 1384 csec->ptrace_sid = psec->sid;
1385 return rc;
1386}
1387
1388static int selinux_capget(struct task_struct *target, kernel_cap_t *effective,
1389 kernel_cap_t *inheritable, kernel_cap_t *permitted)
1390{
1391 int error;
1392
1393 error = task_has_perm(current, target, PROCESS__GETCAP);
1394 if (error)
1395 return error;
1396
1397 return secondary_ops->capget(target, effective, inheritable, permitted);
1398}
1399
1400static int selinux_capset_check(struct task_struct *target, kernel_cap_t *effective,
1401 kernel_cap_t *inheritable, kernel_cap_t *permitted)
1402{
1403 int error;
1404
1405 error = secondary_ops->capset_check(target, effective, inheritable, permitted);
1406 if (error)
1407 return error;
1408
1409 return task_has_perm(current, target, PROCESS__SETCAP);
1410}
1411
1412static void selinux_capset_set(struct task_struct *target, kernel_cap_t *effective,
1413 kernel_cap_t *inheritable, kernel_cap_t *permitted)
1414{
1415 secondary_ops->capset_set(target, effective, inheritable, permitted);
1416}
1417
1418static int selinux_capable(struct task_struct *tsk, int cap)
1419{
1420 int rc;
1421
1422 rc = secondary_ops->capable(tsk, cap);
1423 if (rc)
1424 return rc;
1425
1426 return task_has_capability(tsk,cap);
1427}
1428
3fbfa981
EB		 1429static int selinux_sysctl_get_sid(ctl_table *table, u16 tclass, u32 *sid)
1430{
1431 int buflen, rc;
1432 char *buffer, *path, *end;
1433
1434 rc = -ENOMEM;
1435 buffer = (char*)__get_free_page(GFP_KERNEL);
1436 if (!buffer)
1437 goto out;
1438
1439 buflen = PAGE_SIZE;
1440 end = buffer+buflen;
1441 *--end = '\0';
1442 buflen--;
1443 path = end-1;
1444 *path = '/';
1445 while (table) {
1446 const char *name = table->procname;
1447 size_t namelen = strlen(name);
1448 buflen -= namelen + 1;
1449 if (buflen < 0)
1450 goto out_free;
1451 end -= namelen;
1452 memcpy(end, name, namelen);
1453 *--end = '/';
1454 path = end;
1455 table = table->parent;
1456 }
b599fdfd
EB		 1457 buflen -= 4;
1458 if (buflen < 0)
1459 goto out_free;
1460 end -= 4;
1461 memcpy(end, "/sys", 4);
1462 path = end;
3fbfa981
EB		 1463 rc = security_genfs_sid("proc", path, tclass, sid);
1464out_free:
1465 free_page((unsigned long)buffer);
1466out:
1467 return rc;
1468}
1469
1da177e4
LT		 1470static int selinux_sysctl(ctl_table *table, int op)
1471{
1472 int error = 0;
1473 u32 av;
1474 struct task_security_struct *tsec;
1475 u32 tsid;
1476 int rc;
1477
1478 rc = secondary_ops->sysctl(table, op);
1479 if (rc)
1480 return rc;
1481
1482 tsec = current->security;
1483
3fbfa981
EB		 1484 rc = selinux_sysctl_get_sid(table, (op == 0001) ?
1485 SECCLASS_DIR : SECCLASS_FILE, &tsid);
1da177e4
LT		 1486 if (rc) {
1487 /* Default to the well-defined sysctl SID. */
1488 tsid = SECINITSID_SYSCTL;
1489 }
1490
1491 /* The op values are "defined" in sysctl.c, thereby creating
1492 * a bad coupling between this module and sysctl.c */
1493 if(op == 001) {
1494 error = avc_has_perm(tsec->sid, tsid,
1495 SECCLASS_DIR, DIR__SEARCH, NULL);
1496 } else {
1497 av = 0;
1498 if (op & 004)
1499 av |= FILE__READ;
1500 if (op & 002)
1501 av |= FILE__WRITE;
1502 if (av)
1503 error = avc_has_perm(tsec->sid, tsid,
1504 SECCLASS_FILE, av, NULL);
1505 }
1506
1507 return error;
1508}
1509
1510static int selinux_quotactl(int cmds, int type, int id, struct super_block *sb)
1511{
1512 int rc = 0;
1513
1514 if (!sb)
1515 return 0;
1516
1517 switch (cmds) {
1518 case Q_SYNC:
1519 case Q_QUOTAON:
1520 case Q_QUOTAOFF:
1521 case Q_SETINFO:
1522 case Q_SETQUOTA:
1523 rc = superblock_has_perm(current,
1524 sb,
1525 FILESYSTEM__QUOTAMOD, NULL);
1526 break;
1527 case Q_GETFMT:
1528 case Q_GETINFO:
1529 case Q_GETQUOTA:
1530 rc = superblock_has_perm(current,
1531 sb,
1532 FILESYSTEM__QUOTAGET, NULL);
1533 break;
1534 default:
1535 rc = 0; /* let the kernel handle invalid cmds */
1536 break;
1537 }
1538 return rc;
1539}
1540
1541static int selinux_quota_on(struct dentry *dentry)
1542{
1543 return dentry_has_perm(current, NULL, dentry, FILE__QUOTAON);
1544}
1545
1546static int selinux_syslog(int type)
1547{
1548 int rc;
1549
1550 rc = secondary_ops->syslog(type);
1551 if (rc)
1552 return rc;
1553
1554 switch (type) {
1555 case 3: /* Read last kernel messages */
1556 case 10: /* Return size of the log buffer */
1557 rc = task_has_system(current, SYSTEM__SYSLOG_READ);
1558 break;
1559 case 6: /* Disable logging to console */
1560 case 7: /* Enable logging to console */
1561 case 8: /* Set level of messages printed to console */
1562 rc = task_has_system(current, SYSTEM__SYSLOG_CONSOLE);
1563 break;
1564 case 0: /* Close log */
1565 case 1: /* Open log */
1566 case 2: /* Read from log */
1567 case 4: /* Read/clear last kernel messages */
1568 case 5: /* Clear ring buffer */
1569 default:
1570 rc = task_has_system(current, SYSTEM__SYSLOG_MOD);
1571 break;
1572 }
1573 return rc;
1574}
1575
1576/*
1577 * Check that a process has enough memory to allocate a new virtual
1578 * mapping. 0 means there is enough memory for the allocation to
1579 * succeed and -ENOMEM implies there is not.
1580 *
1581 * Note that secondary_ops->capable and task_has_perm_noaudit return 0
1582 * if the capability is granted, but __vm_enough_memory requires 1 if
1583 * the capability is granted.
1584 *
1585 * Do not audit the selinux permission check, as this is applied to all
1586 * processes that allocate mappings.
1587 */
1588static int selinux_vm_enough_memory(long pages)
1589{
1590 int rc, cap_sys_admin = 0;
1591 struct task_security_struct *tsec = current->security;
1592
1593 rc = secondary_ops->capable(current, CAP_SYS_ADMIN);
1594 if (rc == 0)
1595 rc = avc_has_perm_noaudit(tsec->sid, tsec->sid,
1596 SECCLASS_CAPABILITY,
1597 CAP_TO_MASK(CAP_SYS_ADMIN),
1598 NULL);
1599
1600 if (rc == 0)
1601 cap_sys_admin = 1;
1602
1603 return __vm_enough_memory(pages, cap_sys_admin);
1604}
1605
1606/* binprm security operations */
1607
1608static int selinux_bprm_alloc_security(struct linux_binprm *bprm)
1609{
1610 struct bprm_security_struct *bsec;
1611
89d155ef 1612 bsec = kzalloc(sizeof(struct bprm_security_struct), GFP_KERNEL);
1da177e4
LT		 1613 if (!bsec)
1614 return -ENOMEM;
1615
1da177e4
LT		 1616 bsec->bprm = bprm;
1617 bsec->sid = SECINITSID_UNLABELED;
1618 bsec->set = 0;
1619
1620 bprm->security = bsec;
1621 return 0;
1622}
1623
1624static int selinux_bprm_set_security(struct linux_binprm *bprm)
1625{
1626 struct task_security_struct *tsec;
3d5ff529 1627 struct inode *inode = bprm->file->f_path.dentry->d_inode;
1da177e4
LT		 1628 struct inode_security_struct *isec;
1629 struct bprm_security_struct *bsec;
1630 u32 newsid;
1631 struct avc_audit_data ad;
1632 int rc;
1633
1634 rc = secondary_ops->bprm_set_security(bprm);
1635 if (rc)
1636 return rc;
1637
1638 bsec = bprm->security;
1639
1640 if (bsec->set)
1641 return 0;
1642
1643 tsec = current->security;
1644 isec = inode->i_security;
1645
1646 /* Default to the current task SID. */
1647 bsec->sid = tsec->sid;
1648
28eba5bf 1649 /* Reset fs, key, and sock SIDs on execve. */
1da177e4 1650 tsec->create_sid = 0;
28eba5bf 1651 tsec->keycreate_sid = 0;
42c3e03e 1652 tsec->sockcreate_sid = 0;
1da177e4
LT		 1653
1654 if (tsec->exec_sid) {
1655 newsid = tsec->exec_sid;
1656 /* Reset exec SID on execve. */
1657 tsec->exec_sid = 0;
1658 } else {
1659 /* Check for a default transition on this program. */
1660 rc = security_transition_sid(tsec->sid, isec->sid,
1661 SECCLASS_PROCESS, &newsid);
1662 if (rc)
1663 return rc;
1664 }
1665
1666 AVC_AUDIT_DATA_INIT(&ad, FS);
3d5ff529
JS		 1667 ad.u.fs.mnt = bprm->file->f_path.mnt;
1668 ad.u.fs.dentry = bprm->file->f_path.dentry;
1da177e4 1669
3d5ff529 1670 if (bprm->file->f_path.mnt->mnt_flags & MNT_NOSUID)
1da177e4
LT		 1671 newsid = tsec->sid;
1672
1673 if (tsec->sid == newsid) {
1674 rc = avc_has_perm(tsec->sid, isec->sid,
1675 SECCLASS_FILE, FILE__EXECUTE_NO_TRANS, &ad);
1676 if (rc)
1677 return rc;
1678 } else {
1679 /* Check permissions for the transition. */
1680 rc = avc_has_perm(tsec->sid, newsid,
1681 SECCLASS_PROCESS, PROCESS__TRANSITION, &ad);
1682 if (rc)
1683 return rc;
1684
1685 rc = avc_has_perm(newsid, isec->sid,
1686 SECCLASS_FILE, FILE__ENTRYPOINT, &ad);
1687 if (rc)
1688 return rc;
1689
1690 /* Clear any possibly unsafe personality bits on exec: */
1691 current->personality &= ~PER_CLEAR_ON_SETID;
1692
1693 /* Set the security field to the new SID. */
1694 bsec->sid = newsid;
1695 }
1696
1697 bsec->set = 1;
1698 return 0;
1699}
1700
1701static int selinux_bprm_check_security (struct linux_binprm *bprm)
1702{
1703 return secondary_ops->bprm_check_security(bprm);
1704}
1705
1706
1707static int selinux_bprm_secureexec (struct linux_binprm *bprm)
1708{
1709 struct task_security_struct *tsec = current->security;
1710 int atsecure = 0;
1711
1712 if (tsec->osid != tsec->sid) {
1713 /* Enable secure mode for SIDs transitions unless
1714 the noatsecure permission is granted between
1715 the two SIDs, i.e. ahp returns 0. */
1716 atsecure = avc_has_perm(tsec->osid, tsec->sid,
1717 SECCLASS_PROCESS,
1718 PROCESS__NOATSECURE, NULL);
1719 }
1720
1721 return (atsecure || secondary_ops->bprm_secureexec(bprm));
1722}
1723
1724static void selinux_bprm_free_security(struct linux_binprm *bprm)
1725{
9a5f04bf 1726 kfree(bprm->security);
1da177e4 1727 bprm->security = NULL;
1da177e4
LT		 1728}
1729
1730extern struct vfsmount *selinuxfs_mount;
1731extern struct dentry *selinux_null;
1732
1733/* Derived from fs/exec.c:flush_old_files. */
1734static inline void flush_unauthorized_files(struct files_struct * files)
1735{
1736 struct avc_audit_data ad;
1737 struct file *file, *devnull = NULL;
b20c8122 1738 struct tty_struct *tty;
badf1662 1739 struct fdtable *fdt;
1da177e4 1740 long j = -1;
24ec839c 1741 int drop_tty = 0;
1da177e4 1742
b20c8122 1743 mutex_lock(&tty_mutex);
24ec839c 1744 tty = get_current_tty();
1da177e4
LT		 1745 if (tty) {
1746 file_list_lock();
2f512016 1747 file = list_entry(tty->tty_files.next, typeof(*file), f_u.fu_list);
1da177e4
LT		 1748 if (file) {
1749 /* Revalidate access to controlling tty.
1750 Use inode_has_perm on the tty inode directly rather
1751 than using file_has_perm, as this particular open
1752 file may belong to another process and we are only
1753 interested in the inode-based check here. */
3d5ff529 1754 struct inode *inode = file->f_path.dentry->d_inode;
1da177e4
LT		 1755 if (inode_has_perm(current, inode,
1756 FILE__READ | FILE__WRITE, NULL)) {
24ec839c 1757 drop_tty = 1;
1da177e4
LT		 1758 }
1759 }
1760 file_list_unlock();
24ec839c
PZ		 1761
1762 /* Reset controlling tty. */
1763 if (drop_tty)
1764 proc_set_tty(current, NULL);
1da177e4 1765 }
b20c8122 1766 mutex_unlock(&tty_mutex);
1da177e4
LT		 1767
1768 /* Revalidate access to inherited open files. */
1769
1770 AVC_AUDIT_DATA_INIT(&ad,FS);
1771
1772 spin_lock(&files->file_lock);
1773 for (;;) {
1774 unsigned long set, i;
1775 int fd;
1776
1777 j++;
1778 i = j * __NFDBITS;
badf1662 1779 fdt = files_fdtable(files);
bbea9f69 1780 if (i >= fdt->max_fds)
1da177e4 1781 break;
badf1662 1782 set = fdt->open_fds->fds_bits[j];
1da177e4
LT		 1783 if (!set)
1784 continue;
1785 spin_unlock(&files->file_lock);
1786 for ( ; set ; i++,set >>= 1) {
1787 if (set & 1) {
1788 file = fget(i);
1789 if (!file)
1790 continue;
1791 if (file_has_perm(current,
1792 file,
1793 file_to_av(file))) {
1794 sys_close(i);
1795 fd = get_unused_fd();
1796 if (fd != i) {
1797 if (fd >= 0)
1798 put_unused_fd(fd);
1799 fput(file);
1800 continue;
1801 }
1802 if (devnull) {
095975da 1803 get_file(devnull);
1da177e4
LT		 1804 } else {
1805 devnull = dentry_open(dget(selinux_null), mntget(selinuxfs_mount), O_RDWR);
fc5d81e6
AM		 1806 if (IS_ERR(devnull)) {
1807 devnull = NULL;
1da177e4
LT		 1808 put_unused_fd(fd);
1809 fput(file);
1810 continue;
1811 }
1812 }
1813 fd_install(fd, devnull);
1814 }
1815 fput(file);
1816 }
1817 }
1818 spin_lock(&files->file_lock);
1819
1820 }
1821 spin_unlock(&files->file_lock);
1822}
1823
1824static void selinux_bprm_apply_creds(struct linux_binprm *bprm, int unsafe)
1825{
1826 struct task_security_struct *tsec;
1827 struct bprm_security_struct *bsec;
1828 u32 sid;
1829 int rc;
1830
1831 secondary_ops->bprm_apply_creds(bprm, unsafe);
1832
1833 tsec = current->security;
1834
1835 bsec = bprm->security;
1836 sid = bsec->sid;
1837
1838 tsec->osid = tsec->sid;
1839 bsec->unsafe = 0;
1840 if (tsec->sid != sid) {
1841 /* Check for shared state. If not ok, leave SID
1842 unchanged and kill. */
1843 if (unsafe & LSM_UNSAFE_SHARE) {
1844 rc = avc_has_perm(tsec->sid, sid, SECCLASS_PROCESS,
1845 PROCESS__SHARE, NULL);
1846 if (rc) {
1847 bsec->unsafe = 1;
1848 return;
1849 }
1850 }
1851
1852 /* Check for ptracing, and update the task SID if ok.
1853 Otherwise, leave SID unchanged and kill. */
1854 if (unsafe & (LSM_UNSAFE_PTRACE | LSM_UNSAFE_PTRACE_CAP)) {
1855 rc = avc_has_perm(tsec->ptrace_sid, sid,
1856 SECCLASS_PROCESS, PROCESS__PTRACE,
1857 NULL);
1858 if (rc) {
1859 bsec->unsafe = 1;
1860 return;
1861 }
1862 }
1863 tsec->sid = sid;
1864 }
1865}
1866
1867/*
1868 * called after apply_creds without the task lock held
1869 */
1870static void selinux_bprm_post_apply_creds(struct linux_binprm *bprm)
1871{
1872 struct task_security_struct *tsec;
1873 struct rlimit *rlim, *initrlim;
1874 struct itimerval itimer;
1875 struct bprm_security_struct *bsec;
1876 int rc, i;
1877
1878 tsec = current->security;
1879 bsec = bprm->security;
1880
1881 if (bsec->unsafe) {
1882 force_sig_specific(SIGKILL, current);
1883 return;
1884 }
1885 if (tsec->osid == tsec->sid)
1886 return;
1887
1888 /* Close files for which the new task SID is not authorized. */
1889 flush_unauthorized_files(current->files);
1890
1891 /* Check whether the new SID can inherit signal state
1892 from the old SID. If not, clear itimers to avoid
1893 subsequent signal generation and flush and unblock
1894 signals. This must occur _after_ the task SID has
1895 been updated so that any kill done after the flush
1896 will be checked against the new SID. */
1897 rc = avc_has_perm(tsec->osid, tsec->sid, SECCLASS_PROCESS,
1898 PROCESS__SIGINH, NULL);
1899 if (rc) {
1900 memset(&itimer, 0, sizeof itimer);
1901 for (i = 0; i < 3; i++)
1902 do_setitimer(i, &itimer, NULL);
1903 flush_signals(current);
1904 spin_lock_irq(&current->sighand->siglock);
1905 flush_signal_handlers(current, 1);
1906 sigemptyset(&current->blocked);
1907 recalc_sigpending();
1908 spin_unlock_irq(&current->sighand->siglock);
1909 }
1910
1911 /* Check whether the new SID can inherit resource limits
1912 from the old SID. If not, reset all soft limits to
1913 the lower of the current task's hard limit and the init
1914 task's soft limit. Note that the setting of hard limits
1915 (even to lower them) can be controlled by the setrlimit
1916 check. The inclusion of the init task's soft limit into
1917 the computation is to avoid resetting soft limits higher
1918 than the default soft limit for cases where the default
1919 is lower than the hard limit, e.g. RLIMIT_CORE or
1920 RLIMIT_STACK.*/
1921 rc = avc_has_perm(tsec->osid, tsec->sid, SECCLASS_PROCESS,
1922 PROCESS__RLIMITINH, NULL);
1923 if (rc) {
1924 for (i = 0; i < RLIM_NLIMITS; i++) {
1925 rlim = current->signal->rlim + i;
1926 initrlim = init_task.signal->rlim+i;
1927 rlim->rlim_cur = min(rlim->rlim_max,initrlim->rlim_cur);
1928 }
1929 if (current->signal->rlim[RLIMIT_CPU].rlim_cur != RLIM_INFINITY) {
1930 /*
1931 * This will cause RLIMIT_CPU calculations
1932 * to be refigured.
1933 */
1934 current->it_prof_expires = jiffies_to_cputime(1);
1935 }
1936 }
1937
1938 /* Wake up the parent if it is waiting so that it can
1939 recheck wait permission to the new task SID. */
1940 wake_up_interruptible(&current->parent->signal->wait_chldexit);
1941}
1942
1943/* superblock security operations */
1944
1945static int selinux_sb_alloc_security(struct super_block *sb)
1946{
1947 return superblock_alloc_security(sb);
1948}
1949
1950static void selinux_sb_free_security(struct super_block *sb)
1951{
1952 superblock_free_security(sb);
1953}
1954
1955static inline int match_prefix(char *prefix, int plen, char *option, int olen)
1956{
1957 if (plen > olen)
1958 return 0;
1959
1960 return !memcmp(prefix, option, plen);
1961}
1962
1963static inline int selinux_option(char *option, int len)
1964{
1965 return (match_prefix("context=", sizeof("context=")-1, option, len) ||
1966 match_prefix("fscontext=", sizeof("fscontext=")-1, option, len) ||
0808925e
EP		 1967 match_prefix("defcontext=", sizeof("defcontext=")-1, option, len) ||
1968 match_prefix("rootcontext=", sizeof("rootcontext=")-1, option, len));
1da177e4
LT		 1969}
1970
1971static inline void take_option(char **to, char *from, int *first, int len)
1972{
1973 if (!*first) {
1974 **to = ',';
1975 *to += 1;
3528a953 1976 } else
1da177e4
LT		 1977 *first = 0;
1978 memcpy(*to, from, len);
1979 *to += len;
1980}
1981
3528a953
CO		 1982static inline void take_selinux_option(char **to, char *from, int *first,
1983 int len)
1984{
1985 int current_size = 0;
1986
1987 if (!*first) {
1988 **to = '|';
1989 *to += 1;
1990 }
1991 else
1992 *first = 0;
1993
1994 while (current_size < len) {
1995 if (*from != '"') {
1996 **to = *from;
1997 *to += 1;
1998 }
1999 from += 1;
2000 current_size += 1;
2001 }
2002}
2003
1da177e4
LT		 2004static int selinux_sb_copy_data(struct file_system_type *type, void *orig, void *copy)
2005{
2006 int fnosec, fsec, rc = 0;
2007 char *in_save, *in_curr, *in_end;
2008 char *sec_curr, *nosec_save, *nosec;
3528a953 2009 int open_quote = 0;
1da177e4
LT		 2010
2011 in_curr = orig;
2012 sec_curr = copy;
2013
2014 /* Binary mount data: just copy */
2015 if (type->fs_flags & FS_BINARY_MOUNTDATA) {
2016 copy_page(sec_curr, in_curr);
2017 goto out;
2018 }
2019
2020 nosec = (char *)get_zeroed_page(GFP_KERNEL);
2021 if (!nosec) {
2022 rc = -ENOMEM;
2023 goto out;
2024 }
2025
2026 nosec_save = nosec;
2027 fnosec = fsec = 1;
2028 in_save = in_end = orig;
2029
2030 do {
3528a953
CO		 2031 if (*in_end == '"')
2032 open_quote = !open_quote;
2033 if ((*in_end == ',' && open_quote == 0) ||
2034 *in_end == '\0') {
1da177e4
LT		 2035 int len = in_end - in_curr;
2036
2037 if (selinux_option(in_curr, len))
3528a953 2038 take_selinux_option(&sec_curr, in_curr, &fsec, len);
1da177e4
LT		 2039 else
2040 take_option(&nosec, in_curr, &fnosec, len);
2041
2042 in_curr = in_end + 1;
2043 }
2044 } while (*in_end++);
2045
6931dfc9 2046 strcpy(in_save, nosec_save);
da3caa20 2047 free_page((unsigned long)nosec_save);
1da177e4
LT		 2048out:
2049 return rc;
2050}
2051
2052static int selinux_sb_kern_mount(struct super_block *sb, void *data)
2053{
2054 struct avc_audit_data ad;
2055 int rc;
2056
2057 rc = superblock_doinit(sb, data);
2058 if (rc)
2059 return rc;
2060
2061 AVC_AUDIT_DATA_INIT(&ad,FS);
2062 ad.u.fs.dentry = sb->s_root;
2063 return superblock_has_perm(current, sb, FILESYSTEM__MOUNT, &ad);
2064}
2065
726c3342 2066static int selinux_sb_statfs(struct dentry *dentry)
1da177e4
LT		 2067{
2068 struct avc_audit_data ad;
2069
2070 AVC_AUDIT_DATA_INIT(&ad,FS);
726c3342
DH		 2071 ad.u.fs.dentry = dentry->d_sb->s_root;
2072 return superblock_has_perm(current, dentry->d_sb, FILESYSTEM__GETATTR, &ad);
1da177e4
LT		 2073}
2074
2075static int selinux_mount(char * dev_name,
2076 struct nameidata *nd,
2077 char * type,
2078 unsigned long flags,
2079 void * data)
2080{
2081 int rc;
2082
2083 rc = secondary_ops->sb_mount(dev_name, nd, type, flags, data);
2084 if (rc)
2085 return rc;
2086
2087 if (flags & MS_REMOUNT)
2088 return superblock_has_perm(current, nd->mnt->mnt_sb,
2089 FILESYSTEM__REMOUNT, NULL);
2090 else
2091 return dentry_has_perm(current, nd->mnt, nd->dentry,
2092 FILE__MOUNTON);
2093}
2094
2095static int selinux_umount(struct vfsmount *mnt, int flags)
2096{
2097 int rc;
2098
2099 rc = secondary_ops->sb_umount(mnt, flags);
2100 if (rc)
2101 return rc;
2102
2103 return superblock_has_perm(current,mnt->mnt_sb,
2104 FILESYSTEM__UNMOUNT,NULL);
2105}
2106
2107/* inode security operations */
2108
2109static int selinux_inode_alloc_security(struct inode *inode)
2110{
2111 return inode_alloc_security(inode);
2112}
2113
2114static void selinux_inode_free_security(struct inode *inode)
2115{
2116 inode_free_security(inode);
2117}
2118
5e41ff9e
SS		 2119static int selinux_inode_init_security(struct inode *inode, struct inode *dir,
2120 char **name, void **value,
2121 size_t *len)
2122{
2123 struct task_security_struct *tsec;
2124 struct inode_security_struct *dsec;
2125 struct superblock_security_struct *sbsec;
570bc1c2 2126 u32 newsid, clen;
5e41ff9e 2127 int rc;
570bc1c2 2128 char *namep = NULL, *context;
5e41ff9e
SS		 2129
2130 tsec = current->security;
2131 dsec = dir->i_security;
2132 sbsec = dir->i_sb->s_security;
5e41ff9e
SS		 2133
2134 if (tsec->create_sid && sbsec->behavior != SECURITY_FS_USE_MNTPOINT) {
2135 newsid = tsec->create_sid;
2136 } else {
2137 rc = security_transition_sid(tsec->sid, dsec->sid,
2138 inode_mode_to_security_class(inode->i_mode),
2139 &newsid);
2140 if (rc) {
2141 printk(KERN_WARNING "%s: "
2142 "security_transition_sid failed, rc=%d (dev=%s "
2143 "ino=%ld)\n",
2144 __FUNCTION__,
2145 -rc, inode->i_sb->s_id, inode->i_ino);
2146 return rc;
2147 }
2148 }
2149
296fddf7
EP		 2150 /* Possibly defer initialization to selinux_complete_init. */
2151 if (sbsec->initialized) {
2152 struct inode_security_struct *isec = inode->i_security;
2153 isec->sclass = inode_mode_to_security_class(inode->i_mode);
2154 isec->sid = newsid;
2155 isec->initialized = 1;
2156 }
5e41ff9e 2157
8aad3875 2158 if (!ss_initialized || sbsec->behavior == SECURITY_FS_USE_MNTPOINT)
25a74f3b
SS		 2159 return -EOPNOTSUPP;
2160
570bc1c2
SS		 2161 if (name) {
2162 namep = kstrdup(XATTR_SELINUX_SUFFIX, GFP_KERNEL);
2163 if (!namep)
2164 return -ENOMEM;
2165 *name = namep;
2166 }
5e41ff9e 2167
570bc1c2
SS		 2168 if (value && len) {
2169 rc = security_sid_to_context(newsid, &context, &clen);
2170 if (rc) {
2171 kfree(namep);
2172 return rc;
2173 }
2174 *value = context;
2175 *len = clen;
5e41ff9e 2176 }
5e41ff9e 2177
5e41ff9e
SS		 2178 return 0;
2179}
2180
1da177e4
LT		 2181static int selinux_inode_create(struct inode *dir, struct dentry *dentry, int mask)
2182{
2183 return may_create(dir, dentry, SECCLASS_FILE);
2184}
2185
1da177e4
LT		 2186static int selinux_inode_link(struct dentry *old_dentry, struct inode *dir, struct dentry *new_dentry)
2187{
2188 int rc;
2189
2190 rc = secondary_ops->inode_link(old_dentry,dir,new_dentry);
2191 if (rc)
2192 return rc;
2193 return may_link(dir, old_dentry, MAY_LINK);
2194}
2195
1da177e4
LT		 2196static int selinux_inode_unlink(struct inode *dir, struct dentry *dentry)
2197{
2198 int rc;
2199
2200 rc = secondary_ops->inode_unlink(dir, dentry);
2201 if (rc)
2202 return rc;
2203 return may_link(dir, dentry, MAY_UNLINK);
2204}
2205
2206static int selinux_inode_symlink(struct inode *dir, struct dentry *dentry, const char *name)
2207{
2208 return may_create(dir, dentry, SECCLASS_LNK_FILE);
2209}
2210
1da177e4
LT		 2211static int selinux_inode_mkdir(struct inode *dir, struct dentry *dentry, int mask)
2212{
2213 return may_create(dir, dentry, SECCLASS_DIR);
2214}
2215
1da177e4
LT		 2216static int selinux_inode_rmdir(struct inode *dir, struct dentry *dentry)
2217{
2218 return may_link(dir, dentry, MAY_RMDIR);
2219}
2220
2221static int selinux_inode_mknod(struct inode *dir, struct dentry *dentry, int mode, dev_t dev)
2222{
2223 int rc;
2224
2225 rc = secondary_ops->inode_mknod(dir, dentry, mode, dev);
2226 if (rc)
2227 return rc;
2228
2229 return may_create(dir, dentry, inode_mode_to_security_class(mode));
2230}
2231
1da177e4
LT		 2232static int selinux_inode_rename(struct inode *old_inode, struct dentry *old_dentry,
2233 struct inode *new_inode, struct dentry *new_dentry)
2234{
2235 return may_rename(old_inode, old_dentry, new_inode, new_dentry);
2236}
2237
1da177e4
LT		 2238static int selinux_inode_readlink(struct dentry *dentry)
2239{
2240 return dentry_has_perm(current, NULL, dentry, FILE__READ);
2241}
2242
2243static int selinux_inode_follow_link(struct dentry *dentry, struct nameidata *nameidata)
2244{
2245 int rc;
2246
2247 rc = secondary_ops->inode_follow_link(dentry,nameidata);
2248 if (rc)
2249 return rc;
2250 return dentry_has_perm(current, NULL, dentry, FILE__READ);
2251}
2252
2253static int selinux_inode_permission(struct inode *inode, int mask,
2254 struct nameidata *nd)
2255{
2256 int rc;
2257
2258 rc = secondary_ops->inode_permission(inode, mask, nd);
2259 if (rc)
2260 return rc;
2261
2262 if (!mask) {
2263 /* No permission to check. Existence test. */
2264 return 0;
2265 }
2266
2267 return inode_has_perm(current, inode,
2268 file_mask_to_av(inode->i_mode, mask), NULL);
2269}
2270
2271static int selinux_inode_setattr(struct dentry *dentry, struct iattr *iattr)
2272{
2273 int rc;
2274
2275 rc = secondary_ops->inode_setattr(dentry, iattr);
2276 if (rc)
2277 return rc;
2278
2279 if (iattr->ia_valid & ATTR_FORCE)
2280 return 0;
2281
2282 if (iattr->ia_valid & (ATTR_MODE | ATTR_UID | ATTR_GID |
2283 ATTR_ATIME_SET | ATTR_MTIME_SET))
2284 return dentry_has_perm(current, NULL, dentry, FILE__SETATTR);
2285
2286 return dentry_has_perm(current, NULL, dentry, FILE__WRITE);
2287}
2288
2289static int selinux_inode_getattr(struct vfsmount *mnt, struct dentry *dentry)
2290{
2291 return dentry_has_perm(current, mnt, dentry, FILE__GETATTR);
2292}
2293
2294static int selinux_inode_setxattr(struct dentry *dentry, char *name, void *value, size_t size, int flags)
2295{
2296 struct task_security_struct *tsec = current->security;
2297 struct inode *inode = dentry->d_inode;
2298 struct inode_security_struct *isec = inode->i_security;
2299 struct superblock_security_struct *sbsec;
2300 struct avc_audit_data ad;
2301 u32 newsid;
2302 int rc = 0;
2303
2304 if (strcmp(name, XATTR_NAME_SELINUX)) {
2305 if (!strncmp(name, XATTR_SECURITY_PREFIX,
2306 sizeof XATTR_SECURITY_PREFIX - 1) &&
2307 !capable(CAP_SYS_ADMIN)) {
2308 /* A different attribute in the security namespace.
2309 Restrict to administrator. */
2310 return -EPERM;
2311 }
2312
2313 /* Not an attribute we recognize, so just check the
2314 ordinary setattr permission. */
2315 return dentry_has_perm(current, NULL, dentry, FILE__SETATTR);
2316 }
2317
2318 sbsec = inode->i_sb->s_security;
2319 if (sbsec->behavior == SECURITY_FS_USE_MNTPOINT)
2320 return -EOPNOTSUPP;
2321
2322 if ((current->fsuid != inode->i_uid) && !capable(CAP_FOWNER))
2323 return -EPERM;
2324
2325 AVC_AUDIT_DATA_INIT(&ad,FS);
2326 ad.u.fs.dentry = dentry;
2327
2328 rc = avc_has_perm(tsec->sid, isec->sid, isec->sclass,
2329 FILE__RELABELFROM, &ad);
2330 if (rc)
2331 return rc;
2332
2333 rc = security_context_to_sid(value, size, &newsid);
2334 if (rc)
2335 return rc;
2336
2337 rc = avc_has_perm(tsec->sid, newsid, isec->sclass,
2338 FILE__RELABELTO, &ad);
2339 if (rc)
2340 return rc;
2341
2342 rc = security_validate_transition(isec->sid, newsid, tsec->sid,
2343 isec->sclass);
2344 if (rc)
2345 return rc;
2346
2347 return avc_has_perm(newsid,
2348 sbsec->sid,
2349 SECCLASS_FILESYSTEM,
2350 FILESYSTEM__ASSOCIATE,
2351 &ad);
2352}
2353
2354static void selinux_inode_post_setxattr(struct dentry *dentry, char *name,
2355 void *value, size_t size, int flags)
2356{
2357 struct inode *inode = dentry->d_inode;
2358 struct inode_security_struct *isec = inode->i_security;
2359 u32 newsid;
2360 int rc;
2361
2362 if (strcmp(name, XATTR_NAME_SELINUX)) {
2363 /* Not an attribute we recognize, so nothing to do. */
2364 return;
2365 }
2366
2367 rc = security_context_to_sid(value, size, &newsid);
2368 if (rc) {
2369 printk(KERN_WARNING "%s: unable to obtain SID for context "
2370 "%s, rc=%d\n", __FUNCTION__, (char*)value, -rc);
2371 return;
2372 }
2373
2374 isec->sid = newsid;
2375 return;
2376}
2377
2378static int selinux_inode_getxattr (struct dentry *dentry, char *name)
2379{
1da177e4
LT		 2380 return dentry_has_perm(current, NULL, dentry, FILE__GETATTR);
2381}
2382
2383static int selinux_inode_listxattr (struct dentry *dentry)
2384{
2385 return dentry_has_perm(current, NULL, dentry, FILE__GETATTR);
2386}
2387
2388static int selinux_inode_removexattr (struct dentry *dentry, char *name)
2389{
2390 if (strcmp(name, XATTR_NAME_SELINUX)) {
2391 if (!strncmp(name, XATTR_SECURITY_PREFIX,
2392 sizeof XATTR_SECURITY_PREFIX - 1) &&
2393 !capable(CAP_SYS_ADMIN)) {
2394 /* A different attribute in the security namespace.
2395 Restrict to administrator. */
2396 return -EPERM;
2397 }
2398
2399 /* Not an attribute we recognize, so just check the
2400 ordinary setattr permission. Might want a separate
2401 permission for removexattr. */
2402 return dentry_has_perm(current, NULL, dentry, FILE__SETATTR);
2403 }
2404
2405 /* No one is allowed to remove a SELinux security label.
2406 You can change the label, but all data must be labeled. */
2407 return -EACCES;
2408}
2409
8c8570fb
DK		 2410static const char *selinux_inode_xattr_getsuffix(void)
2411{
2412 return XATTR_SELINUX_SUFFIX;
2413}
2414
d381d8a9
JM		 2415/*
2416 * Copy the in-core inode security context value to the user. If the
2417 * getxattr() prior to this succeeded, check to see if we need to
2418 * canonicalize the value to be finally returned to the user.
2419 *
2420 * Permission check is handled by selinux_inode_getxattr hook.
2421 */
7306a0b9 2422static int selinux_inode_getsecurity(const struct inode *inode, const char *name, void *buffer, size_t size, int err)
1da177e4
LT		 2423{
2424 struct inode_security_struct *isec = inode->i_security;
d381d8a9 2425
8c8570fb
DK		 2426 if (strcmp(name, XATTR_SELINUX_SUFFIX))
2427 return -EOPNOTSUPP;
d381d8a9 2428
8c8570fb 2429 return selinux_getsecurity(isec->sid, buffer, size);
1da177e4
LT		 2430}
2431
2432static int selinux_inode_setsecurity(struct inode *inode, const char *name,
2433 const void *value, size_t size, int flags)
2434{
2435 struct inode_security_struct *isec = inode->i_security;
2436 u32 newsid;
2437 int rc;
2438
2439 if (strcmp(name, XATTR_SELINUX_SUFFIX))
2440 return -EOPNOTSUPP;
2441
2442 if (!value || !size)
2443 return -EACCES;
2444
2445 rc = security_context_to_sid((void*)value, size, &newsid);
2446 if (rc)
2447 return rc;
2448
2449 isec->sid = newsid;
2450 return 0;
2451}
2452
2453static int selinux_inode_listsecurity(struct inode *inode, char *buffer, size_t buffer_size)
2454{
2455 const int len = sizeof(XATTR_NAME_SELINUX);
2456 if (buffer && len <= buffer_size)
2457 memcpy(buffer, XATTR_NAME_SELINUX, len);
2458 return len;
2459}
2460
2461/* file security operations */
2462
2463static int selinux_file_permission(struct file *file, int mask)
2464{
7420ed23 2465 int rc;
3d5ff529 2466 struct inode *inode = file->f_path.dentry->d_inode;
1da177e4
LT		 2467
2468 if (!mask) {
2469 /* No permission to check. Existence test. */
2470 return 0;
2471 }
2472
2473 /* file_mask_to_av won't add FILE__WRITE if MAY_APPEND is set */
2474 if ((file->f_flags & O_APPEND) && (mask & MAY_WRITE))
2475 mask |= MAY_APPEND;
2476
7420ed23
VY		 2477 rc = file_has_perm(current, file,
2478 file_mask_to_av(inode->i_mode, mask));
2479 if (rc)
2480 return rc;
2481
2482 return selinux_netlbl_inode_permission(inode, mask);
1da177e4
LT		 2483}
2484
2485static int selinux_file_alloc_security(struct file *file)
2486{
2487 return file_alloc_security(file);
2488}
2489
2490static void selinux_file_free_security(struct file *file)
2491{
2492 file_free_security(file);
2493}
2494
2495static int selinux_file_ioctl(struct file *file, unsigned int cmd,
2496 unsigned long arg)
2497{
2498 int error = 0;
2499
2500 switch (cmd) {
2501 case FIONREAD:
2502 /* fall through */
2503 case FIBMAP:
2504 /* fall through */
2505 case FIGETBSZ:
2506 /* fall through */
2507 case EXT2_IOC_GETFLAGS:
2508 /* fall through */
2509 case EXT2_IOC_GETVERSION:
2510 error = file_has_perm(current, file, FILE__GETATTR);
2511 break;
2512
2513 case EXT2_IOC_SETFLAGS:
2514 /* fall through */
2515 case EXT2_IOC_SETVERSION:
2516 error = file_has_perm(current, file, FILE__SETATTR);
2517 break;
2518
2519 /* sys_ioctl() checks */
2520 case FIONBIO:
2521 /* fall through */
2522 case FIOASYNC:
2523 error = file_has_perm(current, file, 0);
2524 break;
2525
2526 case KDSKBENT:
2527 case KDSKBSENT:
2528 error = task_has_capability(current,CAP_SYS_TTY_CONFIG);
2529 break;
2530
2531 /* default case assumes that the command will go
2532 * to the file's ioctl() function.
2533 */
2534 default:
2535 error = file_has_perm(current, file, FILE__IOCTL);
2536
2537 }
2538 return error;
2539}
2540
2541static int file_map_prot_check(struct file *file, unsigned long prot, int shared)
2542{
2543#ifndef CONFIG_PPC32
2544 if ((prot & PROT_EXEC) && (!file || (!shared && (prot & PROT_WRITE)))) {
2545 /*
2546 * We are making executable an anonymous mapping or a
2547 * private file mapping that will also be writable.
2548 * This has an additional check.
2549 */
2550 int rc = task_has_perm(current, current, PROCESS__EXECMEM);
2551 if (rc)
2552 return rc;
2553 }
2554#endif
2555
2556 if (file) {
2557 /* read access is always possible with a mapping */
2558 u32 av = FILE__READ;
2559
2560 /* write access only matters if the mapping is shared */
2561 if (shared && (prot & PROT_WRITE))
2562 av |= FILE__WRITE;
2563
2564 if (prot & PROT_EXEC)
2565 av |= FILE__EXECUTE;
2566
2567 return file_has_perm(current, file, av);
2568 }
2569 return 0;
2570}
2571
2572static int selinux_file_mmap(struct file *file, unsigned long reqprot,
2573 unsigned long prot, unsigned long flags)
2574{
2575 int rc;
2576
2577 rc = secondary_ops->file_mmap(file, reqprot, prot, flags);
2578 if (rc)
2579 return rc;
2580
2581 if (selinux_checkreqprot)
2582 prot = reqprot;
2583
2584 return file_map_prot_check(file, prot,
2585 (flags & MAP_TYPE) == MAP_SHARED);
2586}
2587
2588static int selinux_file_mprotect(struct vm_area_struct *vma,
2589 unsigned long reqprot,
2590 unsigned long prot)
2591{
2592 int rc;
2593
2594 rc = secondary_ops->file_mprotect(vma, reqprot, prot);
2595 if (rc)
2596 return rc;
2597
2598 if (selinux_checkreqprot)
2599 prot = reqprot;
2600
2601#ifndef CONFIG_PPC32
db4c9641
SS		 2602 if ((prot & PROT_EXEC) && !(vma->vm_flags & VM_EXEC)) {
2603 rc = 0;
2604 if (vma->vm_start >= vma->vm_mm->start_brk &&
2605 vma->vm_end <= vma->vm_mm->brk) {
2606 rc = task_has_perm(current, current,
2607 PROCESS__EXECHEAP);
2608 } else if (!vma->vm_file &&
2609 vma->vm_start <= vma->vm_mm->start_stack &&
2610 vma->vm_end >= vma->vm_mm->start_stack) {
2611 rc = task_has_perm(current, current, PROCESS__EXECSTACK);
2612 } else if (vma->vm_file && vma->anon_vma) {
2613 /*
2614 * We are making executable a file mapping that has
2615 * had some COW done. Since pages might have been
2616 * written, check ability to execute the possibly
2617 * modified content. This typically should only
2618 * occur for text relocations.
2619 */
2620 rc = file_has_perm(current, vma->vm_file,
2621 FILE__EXECMOD);
2622 }