xref: /openbmc/linux/security/selinux/hooks.c (revision b6dcefde)
1 /*
2  *  NSA Security-Enhanced Linux (SELinux) security module
3  *
4  *  This file contains the SELinux hook function implementations.
5  *
6  *  Authors:  Stephen Smalley, <sds@epoch.ncsc.mil>
7  *	      Chris Vance, <cvance@nai.com>
8  *	      Wayne Salamon, <wsalamon@nai.com>
9  *	      James Morris <jmorris@redhat.com>
10  *
11  *  Copyright (C) 2001,2002 Networks Associates Technology, Inc.
12  *  Copyright (C) 2003-2008 Red Hat, Inc., James Morris <jmorris@redhat.com>
13  *					   Eric Paris <eparis@redhat.com>
14  *  Copyright (C) 2004-2005 Trusted Computer Solutions, Inc.
15  *			    <dgoeddel@trustedcs.com>
16  *  Copyright (C) 2006, 2007, 2009 Hewlett-Packard Development Company, L.P.
17  *	Paul Moore <paul.moore@hp.com>
18  *  Copyright (C) 2007 Hitachi Software Engineering Co., Ltd.
19  *		       Yuichi Nakamura <ynakam@hitachisoft.jp>
20  *
21  *	This program is free software; you can redistribute it and/or modify
22  *	it under the terms of the GNU General Public License version 2,
23  *	as published by the Free Software Foundation.
24  */
25 
26 #include <linux/init.h>
27 #include <linux/kernel.h>
28 #include <linux/tracehook.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>
40 #include <linux/spinlock.h>
41 #include <linux/syscalls.h>
42 #include <linux/file.h>
43 #include <linux/fdtable.h>
44 #include <linux/namei.h>
45 #include <linux/mount.h>
46 #include <linux/proc_fs.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 local_port_range[] */
52 #include <net/tcp.h>		/* struct or_callable used in sock_rcv_skb */
53 #include <net/net_namespace.h>
54 #include <net/netlabel.h>
55 #include <linux/uaccess.h>
56 #include <asm/ioctls.h>
57 #include <asm/atomic.h>
58 #include <linux/bitops.h>
59 #include <linux/interrupt.h>
60 #include <linux/netdevice.h>	/* for network interface checks */
61 #include <linux/netlink.h>
62 #include <linux/tcp.h>
63 #include <linux/udp.h>
64 #include <linux/dccp.h>
65 #include <linux/quota.h>
66 #include <linux/un.h>		/* for Unix socket types */
67 #include <net/af_unix.h>	/* for Unix socket types */
68 #include <linux/parser.h>
69 #include <linux/nfs_mount.h>
70 #include <net/ipv6.h>
71 #include <linux/hugetlb.h>
72 #include <linux/personality.h>
73 #include <linux/sysctl.h>
74 #include <linux/audit.h>
75 #include <linux/string.h>
76 #include <linux/selinux.h>
77 #include <linux/mutex.h>
78 #include <linux/posix-timers.h>
79 
80 #include "avc.h"
81 #include "objsec.h"
82 #include "netif.h"
83 #include "netnode.h"
84 #include "netport.h"
85 #include "xfrm.h"
86 #include "netlabel.h"
87 #include "audit.h"
88 
89 #define XATTR_SELINUX_SUFFIX "selinux"
90 #define XATTR_NAME_SELINUX XATTR_SECURITY_PREFIX XATTR_SELINUX_SUFFIX
91 
92 #define NUM_SEL_MNT_OPTS 5
93 
94 extern int selinux_nlmsg_lookup(u16 sclass, u16 nlmsg_type, u32 *perm);
95 extern struct security_operations *security_ops;
96 
97 /* SECMARK reference count */
98 atomic_t selinux_secmark_refcount = ATOMIC_INIT(0);
99 
100 #ifdef CONFIG_SECURITY_SELINUX_DEVELOP
101 int selinux_enforcing;
102 
103 static int __init enforcing_setup(char *str)
104 {
105 	unsigned long enforcing;
106 	if (!strict_strtoul(str, 0, &enforcing))
107 		selinux_enforcing = enforcing ? 1 : 0;
108 	return 1;
109 }
110 __setup("enforcing=", enforcing_setup);
111 #endif
112 
113 #ifdef CONFIG_SECURITY_SELINUX_BOOTPARAM
114 int selinux_enabled = CONFIG_SECURITY_SELINUX_BOOTPARAM_VALUE;
115 
116 static int __init selinux_enabled_setup(char *str)
117 {
118 	unsigned long enabled;
119 	if (!strict_strtoul(str, 0, &enabled))
120 		selinux_enabled = enabled ? 1 : 0;
121 	return 1;
122 }
123 __setup("selinux=", selinux_enabled_setup);
124 #else
125 int selinux_enabled = 1;
126 #endif
127 
128 
129 /*
130  * Minimal support for a secondary security module,
131  * just to allow the use of the capability module.
132  */
133 static struct security_operations *secondary_ops;
134 
135 /* Lists of inode and superblock security structures initialized
136    before the policy was loaded. */
137 static LIST_HEAD(superblock_security_head);
138 static DEFINE_SPINLOCK(sb_security_lock);
139 
140 static struct kmem_cache *sel_inode_cache;
141 
142 /**
143  * selinux_secmark_enabled - Check to see if SECMARK is currently enabled
144  *
145  * Description:
146  * This function checks the SECMARK reference counter to see if any SECMARK
147  * targets are currently configured, if the reference counter is greater than
148  * zero SECMARK is considered to be enabled.  Returns true (1) if SECMARK is
149  * enabled, false (0) if SECMARK is disabled.
150  *
151  */
152 static int selinux_secmark_enabled(void)
153 {
154 	return (atomic_read(&selinux_secmark_refcount) > 0);
155 }
156 
157 /*
158  * initialise the security for the init task
159  */
160 static void cred_init_security(void)
161 {
162 	struct cred *cred = (struct cred *) current->real_cred;
163 	struct task_security_struct *tsec;
164 
165 	tsec = kzalloc(sizeof(struct task_security_struct), GFP_KERNEL);
166 	if (!tsec)
167 		panic("SELinux:  Failed to initialize initial task.\n");
168 
169 	tsec->osid = tsec->sid = SECINITSID_KERNEL;
170 	cred->security = tsec;
171 }
172 
173 /*
174  * get the security ID of a set of credentials
175  */
176 static inline u32 cred_sid(const struct cred *cred)
177 {
178 	const struct task_security_struct *tsec;
179 
180 	tsec = cred->security;
181 	return tsec->sid;
182 }
183 
184 /*
185  * get the objective security ID of a task
186  */
187 static inline u32 task_sid(const struct task_struct *task)
188 {
189 	u32 sid;
190 
191 	rcu_read_lock();
192 	sid = cred_sid(__task_cred(task));
193 	rcu_read_unlock();
194 	return sid;
195 }
196 
197 /*
198  * get the subjective security ID of the current task
199  */
200 static inline u32 current_sid(void)
201 {
202 	const struct task_security_struct *tsec = current_cred()->security;
203 
204 	return tsec->sid;
205 }
206 
207 /* Allocate and free functions for each kind of security blob. */
208 
209 static int inode_alloc_security(struct inode *inode)
210 {
211 	struct inode_security_struct *isec;
212 	u32 sid = current_sid();
213 
214 	isec = kmem_cache_zalloc(sel_inode_cache, GFP_NOFS);
215 	if (!isec)
216 		return -ENOMEM;
217 
218 	mutex_init(&isec->lock);
219 	INIT_LIST_HEAD(&isec->list);
220 	isec->inode = inode;
221 	isec->sid = SECINITSID_UNLABELED;
222 	isec->sclass = SECCLASS_FILE;
223 	isec->task_sid = sid;
224 	inode->i_security = isec;
225 
226 	return 0;
227 }
228 
229 static void inode_free_security(struct inode *inode)
230 {
231 	struct inode_security_struct *isec = inode->i_security;
232 	struct superblock_security_struct *sbsec = inode->i_sb->s_security;
233 
234 	spin_lock(&sbsec->isec_lock);
235 	if (!list_empty(&isec->list))
236 		list_del_init(&isec->list);
237 	spin_unlock(&sbsec->isec_lock);
238 
239 	inode->i_security = NULL;
240 	kmem_cache_free(sel_inode_cache, isec);
241 }
242 
243 static int file_alloc_security(struct file *file)
244 {
245 	struct file_security_struct *fsec;
246 	u32 sid = current_sid();
247 
248 	fsec = kzalloc(sizeof(struct file_security_struct), GFP_KERNEL);
249 	if (!fsec)
250 		return -ENOMEM;
251 
252 	fsec->sid = sid;
253 	fsec->fown_sid = sid;
254 	file->f_security = fsec;
255 
256 	return 0;
257 }
258 
259 static void file_free_security(struct file *file)
260 {
261 	struct file_security_struct *fsec = file->f_security;
262 	file->f_security = NULL;
263 	kfree(fsec);
264 }
265 
266 static int superblock_alloc_security(struct super_block *sb)
267 {
268 	struct superblock_security_struct *sbsec;
269 
270 	sbsec = kzalloc(sizeof(struct superblock_security_struct), GFP_KERNEL);
271 	if (!sbsec)
272 		return -ENOMEM;
273 
274 	mutex_init(&sbsec->lock);
275 	INIT_LIST_HEAD(&sbsec->list);
276 	INIT_LIST_HEAD(&sbsec->isec_head);
277 	spin_lock_init(&sbsec->isec_lock);
278 	sbsec->sb = sb;
279 	sbsec->sid = SECINITSID_UNLABELED;
280 	sbsec->def_sid = SECINITSID_FILE;
281 	sbsec->mntpoint_sid = SECINITSID_UNLABELED;
282 	sb->s_security = sbsec;
283 
284 	return 0;
285 }
286 
287 static void superblock_free_security(struct super_block *sb)
288 {
289 	struct superblock_security_struct *sbsec = sb->s_security;
290 
291 	spin_lock(&sb_security_lock);
292 	if (!list_empty(&sbsec->list))
293 		list_del_init(&sbsec->list);
294 	spin_unlock(&sb_security_lock);
295 
296 	sb->s_security = NULL;
297 	kfree(sbsec);
298 }
299 
300 static int sk_alloc_security(struct sock *sk, int family, gfp_t priority)
301 {
302 	struct sk_security_struct *ssec;
303 
304 	ssec = kzalloc(sizeof(*ssec), priority);
305 	if (!ssec)
306 		return -ENOMEM;
307 
308 	ssec->peer_sid = SECINITSID_UNLABELED;
309 	ssec->sid = SECINITSID_UNLABELED;
310 	sk->sk_security = ssec;
311 
312 	selinux_netlbl_sk_security_reset(ssec);
313 
314 	return 0;
315 }
316 
317 static void sk_free_security(struct sock *sk)
318 {
319 	struct sk_security_struct *ssec = sk->sk_security;
320 
321 	sk->sk_security = NULL;
322 	selinux_netlbl_sk_security_free(ssec);
323 	kfree(ssec);
324 }
325 
326 /* The security server must be initialized before
327    any labeling or access decisions can be provided. */
328 extern int ss_initialized;
329 
330 /* The file system's label must be initialized prior to use. */
331 
332 static char *labeling_behaviors[6] = {
333 	"uses xattr",
334 	"uses transition SIDs",
335 	"uses task SIDs",
336 	"uses genfs_contexts",
337 	"not configured for labeling",
338 	"uses mountpoint labeling",
339 };
340 
341 static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dentry);
342 
343 static inline int inode_doinit(struct inode *inode)
344 {
345 	return inode_doinit_with_dentry(inode, NULL);
346 }
347 
348 enum {
349 	Opt_error = -1,
350 	Opt_context = 1,
351 	Opt_fscontext = 2,
352 	Opt_defcontext = 3,
353 	Opt_rootcontext = 4,
354 	Opt_labelsupport = 5,
355 };
356 
357 static const match_table_t tokens = {
358 	{Opt_context, CONTEXT_STR "%s"},
359 	{Opt_fscontext, FSCONTEXT_STR "%s"},
360 	{Opt_defcontext, DEFCONTEXT_STR "%s"},
361 	{Opt_rootcontext, ROOTCONTEXT_STR "%s"},
362 	{Opt_labelsupport, LABELSUPP_STR},
363 	{Opt_error, NULL},
364 };
365 
366 #define SEL_MOUNT_FAIL_MSG "SELinux:  duplicate or incompatible mount options\n"
367 
368 static int may_context_mount_sb_relabel(u32 sid,
369 			struct superblock_security_struct *sbsec,
370 			const struct cred *cred)
371 {
372 	const struct task_security_struct *tsec = cred->security;
373 	int rc;
374 
375 	rc = avc_has_perm(tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM,
376 			  FILESYSTEM__RELABELFROM, NULL);
377 	if (rc)
378 		return rc;
379 
380 	rc = avc_has_perm(tsec->sid, sid, SECCLASS_FILESYSTEM,
381 			  FILESYSTEM__RELABELTO, NULL);
382 	return rc;
383 }
384 
385 static int may_context_mount_inode_relabel(u32 sid,
386 			struct superblock_security_struct *sbsec,
387 			const struct cred *cred)
388 {
389 	const struct task_security_struct *tsec = cred->security;
390 	int rc;
391 	rc = avc_has_perm(tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM,
392 			  FILESYSTEM__RELABELFROM, NULL);
393 	if (rc)
394 		return rc;
395 
396 	rc = avc_has_perm(sid, sbsec->sid, SECCLASS_FILESYSTEM,
397 			  FILESYSTEM__ASSOCIATE, NULL);
398 	return rc;
399 }
400 
401 static int sb_finish_set_opts(struct super_block *sb)
402 {
403 	struct superblock_security_struct *sbsec = sb->s_security;
404 	struct dentry *root = sb->s_root;
405 	struct inode *root_inode = root->d_inode;
406 	int rc = 0;
407 
408 	if (sbsec->behavior == SECURITY_FS_USE_XATTR) {
409 		/* Make sure that the xattr handler exists and that no
410 		   error other than -ENODATA is returned by getxattr on
411 		   the root directory.  -ENODATA is ok, as this may be
412 		   the first boot of the SELinux kernel before we have
413 		   assigned xattr values to the filesystem. */
414 		if (!root_inode->i_op->getxattr) {
415 			printk(KERN_WARNING "SELinux: (dev %s, type %s) has no "
416 			       "xattr support\n", sb->s_id, sb->s_type->name);
417 			rc = -EOPNOTSUPP;
418 			goto out;
419 		}
420 		rc = root_inode->i_op->getxattr(root, XATTR_NAME_SELINUX, NULL, 0);
421 		if (rc < 0 && rc != -ENODATA) {
422 			if (rc == -EOPNOTSUPP)
423 				printk(KERN_WARNING "SELinux: (dev %s, type "
424 				       "%s) has no security xattr handler\n",
425 				       sb->s_id, sb->s_type->name);
426 			else
427 				printk(KERN_WARNING "SELinux: (dev %s, type "
428 				       "%s) getxattr errno %d\n", sb->s_id,
429 				       sb->s_type->name, -rc);
430 			goto out;
431 		}
432 	}
433 
434 	sbsec->flags |= (SE_SBINITIALIZED | SE_SBLABELSUPP);
435 
436 	if (sbsec->behavior > ARRAY_SIZE(labeling_behaviors))
437 		printk(KERN_ERR "SELinux: initialized (dev %s, type %s), unknown behavior\n",
438 		       sb->s_id, sb->s_type->name);
439 	else
440 		printk(KERN_DEBUG "SELinux: initialized (dev %s, type %s), %s\n",
441 		       sb->s_id, sb->s_type->name,
442 		       labeling_behaviors[sbsec->behavior-1]);
443 
444 	if (sbsec->behavior == SECURITY_FS_USE_GENFS ||
445 	    sbsec->behavior == SECURITY_FS_USE_MNTPOINT ||
446 	    sbsec->behavior == SECURITY_FS_USE_NONE ||
447 	    sbsec->behavior > ARRAY_SIZE(labeling_behaviors))
448 		sbsec->flags &= ~SE_SBLABELSUPP;
449 
450 	/* Special handling for sysfs. Is genfs but also has setxattr handler*/
451 	if (strncmp(sb->s_type->name, "sysfs", sizeof("sysfs")) == 0)
452 		sbsec->flags |= SE_SBLABELSUPP;
453 
454 	/* Initialize the root inode. */
455 	rc = inode_doinit_with_dentry(root_inode, root);
456 
457 	/* Initialize any other inodes associated with the superblock, e.g.
458 	   inodes created prior to initial policy load or inodes created
459 	   during get_sb by a pseudo filesystem that directly
460 	   populates itself. */
461 	spin_lock(&sbsec->isec_lock);
462 next_inode:
463 	if (!list_empty(&sbsec->isec_head)) {
464 		struct inode_security_struct *isec =
465 				list_entry(sbsec->isec_head.next,
466 					   struct inode_security_struct, list);
467 		struct inode *inode = isec->inode;
468 		spin_unlock(&sbsec->isec_lock);
469 		inode = igrab(inode);
470 		if (inode) {
471 			if (!IS_PRIVATE(inode))
472 				inode_doinit(inode);
473 			iput(inode);
474 		}
475 		spin_lock(&sbsec->isec_lock);
476 		list_del_init(&isec->list);
477 		goto next_inode;
478 	}
479 	spin_unlock(&sbsec->isec_lock);
480 out:
481 	return rc;
482 }
483 
484 /*
485  * This function should allow an FS to ask what it's mount security
486  * options were so it can use those later for submounts, displaying
487  * mount options, or whatever.
488  */
489 static int selinux_get_mnt_opts(const struct super_block *sb,
490 				struct security_mnt_opts *opts)
491 {
492 	int rc = 0, i;
493 	struct superblock_security_struct *sbsec = sb->s_security;
494 	char *context = NULL;
495 	u32 len;
496 	char tmp;
497 
498 	security_init_mnt_opts(opts);
499 
500 	if (!(sbsec->flags & SE_SBINITIALIZED))
501 		return -EINVAL;
502 
503 	if (!ss_initialized)
504 		return -EINVAL;
505 
506 	tmp = sbsec->flags & SE_MNTMASK;
507 	/* count the number of mount options for this sb */
508 	for (i = 0; i < 8; i++) {
509 		if (tmp & 0x01)
510 			opts->num_mnt_opts++;
511 		tmp >>= 1;
512 	}
513 	/* Check if the Label support flag is set */
514 	if (sbsec->flags & SE_SBLABELSUPP)
515 		opts->num_mnt_opts++;
516 
517 	opts->mnt_opts = kcalloc(opts->num_mnt_opts, sizeof(char *), GFP_ATOMIC);
518 	if (!opts->mnt_opts) {
519 		rc = -ENOMEM;
520 		goto out_free;
521 	}
522 
523 	opts->mnt_opts_flags = kcalloc(opts->num_mnt_opts, sizeof(int), GFP_ATOMIC);
524 	if (!opts->mnt_opts_flags) {
525 		rc = -ENOMEM;
526 		goto out_free;
527 	}
528 
529 	i = 0;
530 	if (sbsec->flags & FSCONTEXT_MNT) {
531 		rc = security_sid_to_context(sbsec->sid, &context, &len);
532 		if (rc)
533 			goto out_free;
534 		opts->mnt_opts[i] = context;
535 		opts->mnt_opts_flags[i++] = FSCONTEXT_MNT;
536 	}
537 	if (sbsec->flags & CONTEXT_MNT) {
538 		rc = security_sid_to_context(sbsec->mntpoint_sid, &context, &len);
539 		if (rc)
540 			goto out_free;
541 		opts->mnt_opts[i] = context;
542 		opts->mnt_opts_flags[i++] = CONTEXT_MNT;
543 	}
544 	if (sbsec->flags & DEFCONTEXT_MNT) {
545 		rc = security_sid_to_context(sbsec->def_sid, &context, &len);
546 		if (rc)
547 			goto out_free;
548 		opts->mnt_opts[i] = context;
549 		opts->mnt_opts_flags[i++] = DEFCONTEXT_MNT;
550 	}
551 	if (sbsec->flags & ROOTCONTEXT_MNT) {
552 		struct inode *root = sbsec->sb->s_root->d_inode;
553 		struct inode_security_struct *isec = root->i_security;
554 
555 		rc = security_sid_to_context(isec->sid, &context, &len);
556 		if (rc)
557 			goto out_free;
558 		opts->mnt_opts[i] = context;
559 		opts->mnt_opts_flags[i++] = ROOTCONTEXT_MNT;
560 	}
561 	if (sbsec->flags & SE_SBLABELSUPP) {
562 		opts->mnt_opts[i] = NULL;
563 		opts->mnt_opts_flags[i++] = SE_SBLABELSUPP;
564 	}
565 
566 	BUG_ON(i != opts->num_mnt_opts);
567 
568 	return 0;
569 
570 out_free:
571 	security_free_mnt_opts(opts);
572 	return rc;
573 }
574 
575 static int bad_option(struct superblock_security_struct *sbsec, char flag,
576 		      u32 old_sid, u32 new_sid)
577 {
578 	char mnt_flags = sbsec->flags & SE_MNTMASK;
579 
580 	/* check if the old mount command had the same options */
581 	if (sbsec->flags & SE_SBINITIALIZED)
582 		if (!(sbsec->flags & flag) ||
583 		    (old_sid != new_sid))
584 			return 1;
585 
586 	/* check if we were passed the same options twice,
587 	 * aka someone passed context=a,context=b
588 	 */
589 	if (!(sbsec->flags & SE_SBINITIALIZED))
590 		if (mnt_flags & flag)
591 			return 1;
592 	return 0;
593 }
594 
595 /*
596  * Allow filesystems with binary mount data to explicitly set mount point
597  * labeling information.
598  */
599 static int selinux_set_mnt_opts(struct super_block *sb,
600 				struct security_mnt_opts *opts)
601 {
602 	const struct cred *cred = current_cred();
603 	int rc = 0, i;
604 	struct superblock_security_struct *sbsec = sb->s_security;
605 	const char *name = sb->s_type->name;
606 	struct inode *inode = sbsec->sb->s_root->d_inode;
607 	struct inode_security_struct *root_isec = inode->i_security;
608 	u32 fscontext_sid = 0, context_sid = 0, rootcontext_sid = 0;
609 	u32 defcontext_sid = 0;
610 	char **mount_options = opts->mnt_opts;
611 	int *flags = opts->mnt_opts_flags;
612 	int num_opts = opts->num_mnt_opts;
613 
614 	mutex_lock(&sbsec->lock);
615 
616 	if (!ss_initialized) {
617 		if (!num_opts) {
618 			/* Defer initialization until selinux_complete_init,
619 			   after the initial policy is loaded and the security
620 			   server is ready to handle calls. */
621 			spin_lock(&sb_security_lock);
622 			if (list_empty(&sbsec->list))
623 				list_add(&sbsec->list, &superblock_security_head);
624 			spin_unlock(&sb_security_lock);
625 			goto out;
626 		}
627 		rc = -EINVAL;
628 		printk(KERN_WARNING "SELinux: Unable to set superblock options "
629 			"before the security server is initialized\n");
630 		goto out;
631 	}
632 
633 	/*
634 	 * Binary mount data FS will come through this function twice.  Once
635 	 * from an explicit call and once from the generic calls from the vfs.
636 	 * Since the generic VFS calls will not contain any security mount data
637 	 * we need to skip the double mount verification.
638 	 *
639 	 * This does open a hole in which we will not notice if the first
640 	 * mount using this sb set explict options and a second mount using
641 	 * this sb does not set any security options.  (The first options
642 	 * will be used for both mounts)
643 	 */
644 	if ((sbsec->flags & SE_SBINITIALIZED) && (sb->s_type->fs_flags & FS_BINARY_MOUNTDATA)
645 	    && (num_opts == 0))
646 		goto out;
647 
648 	/*
649 	 * parse the mount options, check if they are valid sids.
650 	 * also check if someone is trying to mount the same sb more
651 	 * than once with different security options.
652 	 */
653 	for (i = 0; i < num_opts; i++) {
654 		u32 sid;
655 
656 		if (flags[i] == SE_SBLABELSUPP)
657 			continue;
658 		rc = security_context_to_sid(mount_options[i],
659 					     strlen(mount_options[i]), &sid);
660 		if (rc) {
661 			printk(KERN_WARNING "SELinux: security_context_to_sid"
662 			       "(%s) failed for (dev %s, type %s) errno=%d\n",
663 			       mount_options[i], sb->s_id, name, rc);
664 			goto out;
665 		}
666 		switch (flags[i]) {
667 		case FSCONTEXT_MNT:
668 			fscontext_sid = sid;
669 
670 			if (bad_option(sbsec, FSCONTEXT_MNT, sbsec->sid,
671 					fscontext_sid))
672 				goto out_double_mount;
673 
674 			sbsec->flags |= FSCONTEXT_MNT;
675 			break;
676 		case CONTEXT_MNT:
677 			context_sid = sid;
678 
679 			if (bad_option(sbsec, CONTEXT_MNT, sbsec->mntpoint_sid,
680 					context_sid))
681 				goto out_double_mount;
682 
683 			sbsec->flags |= CONTEXT_MNT;
684 			break;
685 		case ROOTCONTEXT_MNT:
686 			rootcontext_sid = sid;
687 
688 			if (bad_option(sbsec, ROOTCONTEXT_MNT, root_isec->sid,
689 					rootcontext_sid))
690 				goto out_double_mount;
691 
692 			sbsec->flags |= ROOTCONTEXT_MNT;
693 
694 			break;
695 		case DEFCONTEXT_MNT:
696 			defcontext_sid = sid;
697 
698 			if (bad_option(sbsec, DEFCONTEXT_MNT, sbsec->def_sid,
699 					defcontext_sid))
700 				goto out_double_mount;
701 
702 			sbsec->flags |= DEFCONTEXT_MNT;
703 
704 			break;
705 		default:
706 			rc = -EINVAL;
707 			goto out;
708 		}
709 	}
710 
711 	if (sbsec->flags & SE_SBINITIALIZED) {
712 		/* previously mounted with options, but not on this attempt? */
713 		if ((sbsec->flags & SE_MNTMASK) && !num_opts)
714 			goto out_double_mount;
715 		rc = 0;
716 		goto out;
717 	}
718 
719 	if (strcmp(sb->s_type->name, "proc") == 0)
720 		sbsec->flags |= SE_SBPROC;
721 
722 	/* Determine the labeling behavior to use for this filesystem type. */
723 	rc = security_fs_use((sbsec->flags & SE_SBPROC) ? "proc" : sb->s_type->name, &sbsec->behavior, &sbsec->sid);
724 	if (rc) {
725 		printk(KERN_WARNING "%s: security_fs_use(%s) returned %d\n",
726 		       __func__, sb->s_type->name, rc);
727 		goto out;
728 	}
729 
730 	/* sets the context of the superblock for the fs being mounted. */
731 	if (fscontext_sid) {
732 		rc = may_context_mount_sb_relabel(fscontext_sid, sbsec, cred);
733 		if (rc)
734 			goto out;
735 
736 		sbsec->sid = fscontext_sid;
737 	}
738 
739 	/*
740 	 * Switch to using mount point labeling behavior.
741 	 * sets the label used on all file below the mountpoint, and will set
742 	 * the superblock context if not already set.
743 	 */
744 	if (context_sid) {
745 		if (!fscontext_sid) {
746 			rc = may_context_mount_sb_relabel(context_sid, sbsec,
747 							  cred);
748 			if (rc)
749 				goto out;
750 			sbsec->sid = context_sid;
751 		} else {
752 			rc = may_context_mount_inode_relabel(context_sid, sbsec,
753 							     cred);
754 			if (rc)
755 				goto out;
756 		}
757 		if (!rootcontext_sid)
758 			rootcontext_sid = context_sid;
759 
760 		sbsec->mntpoint_sid = context_sid;
761 		sbsec->behavior = SECURITY_FS_USE_MNTPOINT;
762 	}
763 
764 	if (rootcontext_sid) {
765 		rc = may_context_mount_inode_relabel(rootcontext_sid, sbsec,
766 						     cred);
767 		if (rc)
768 			goto out;
769 
770 		root_isec->sid = rootcontext_sid;
771 		root_isec->initialized = 1;
772 	}
773 
774 	if (defcontext_sid) {
775 		if (sbsec->behavior != SECURITY_FS_USE_XATTR) {
776 			rc = -EINVAL;
777 			printk(KERN_WARNING "SELinux: defcontext option is "
778 			       "invalid for this filesystem type\n");
779 			goto out;
780 		}
781 
782 		if (defcontext_sid != sbsec->def_sid) {
783 			rc = may_context_mount_inode_relabel(defcontext_sid,
784 							     sbsec, cred);
785 			if (rc)
786 				goto out;
787 		}
788 
789 		sbsec->def_sid = defcontext_sid;
790 	}
791 
792 	rc = sb_finish_set_opts(sb);
793 out:
794 	mutex_unlock(&sbsec->lock);
795 	return rc;
796 out_double_mount:
797 	rc = -EINVAL;
798 	printk(KERN_WARNING "SELinux: mount invalid.  Same superblock, different "
799 	       "security settings for (dev %s, type %s)\n", sb->s_id, name);
800 	goto out;
801 }
802 
803 static void selinux_sb_clone_mnt_opts(const struct super_block *oldsb,
804 					struct super_block *newsb)
805 {
806 	const struct superblock_security_struct *oldsbsec = oldsb->s_security;
807 	struct superblock_security_struct *newsbsec = newsb->s_security;
808 
809 	int set_fscontext =	(oldsbsec->flags & FSCONTEXT_MNT);
810 	int set_context =	(oldsbsec->flags & CONTEXT_MNT);
811 	int set_rootcontext =	(oldsbsec->flags & ROOTCONTEXT_MNT);
812 
813 	/*
814 	 * if the parent was able to be mounted it clearly had no special lsm
815 	 * mount options.  thus we can safely put this sb on the list and deal
816 	 * with it later
817 	 */
818 	if (!ss_initialized) {
819 		spin_lock(&sb_security_lock);
820 		if (list_empty(&newsbsec->list))
821 			list_add(&newsbsec->list, &superblock_security_head);
822 		spin_unlock(&sb_security_lock);
823 		return;
824 	}
825 
826 	/* how can we clone if the old one wasn't set up?? */
827 	BUG_ON(!(oldsbsec->flags & SE_SBINITIALIZED));
828 
829 	/* if fs is reusing a sb, just let its options stand... */
830 	if (newsbsec->flags & SE_SBINITIALIZED)
831 		return;
832 
833 	mutex_lock(&newsbsec->lock);
834 
835 	newsbsec->flags = oldsbsec->flags;
836 
837 	newsbsec->sid = oldsbsec->sid;
838 	newsbsec->def_sid = oldsbsec->def_sid;
839 	newsbsec->behavior = oldsbsec->behavior;
840 
841 	if (set_context) {
842 		u32 sid = oldsbsec->mntpoint_sid;
843 
844 		if (!set_fscontext)
845 			newsbsec->sid = sid;
846 		if (!set_rootcontext) {
847 			struct inode *newinode = newsb->s_root->d_inode;
848 			struct inode_security_struct *newisec = newinode->i_security;
849 			newisec->sid = sid;
850 		}
851 		newsbsec->mntpoint_sid = sid;
852 	}
853 	if (set_rootcontext) {
854 		const struct inode *oldinode = oldsb->s_root->d_inode;
855 		const struct inode_security_struct *oldisec = oldinode->i_security;
856 		struct inode *newinode = newsb->s_root->d_inode;
857 		struct inode_security_struct *newisec = newinode->i_security;
858 
859 		newisec->sid = oldisec->sid;
860 	}
861 
862 	sb_finish_set_opts(newsb);
863 	mutex_unlock(&newsbsec->lock);
864 }
865 
866 static int selinux_parse_opts_str(char *options,
867 				  struct security_mnt_opts *opts)
868 {
869 	char *p;
870 	char *context = NULL, *defcontext = NULL;
871 	char *fscontext = NULL, *rootcontext = NULL;
872 	int rc, num_mnt_opts = 0;
873 
874 	opts->num_mnt_opts = 0;
875 
876 	/* Standard string-based options. */
877 	while ((p = strsep(&options, "|")) != NULL) {
878 		int token;
879 		substring_t args[MAX_OPT_ARGS];
880 
881 		if (!*p)
882 			continue;
883 
884 		token = match_token(p, tokens, args);
885 
886 		switch (token) {
887 		case Opt_context:
888 			if (context || defcontext) {
889 				rc = -EINVAL;
890 				printk(KERN_WARNING SEL_MOUNT_FAIL_MSG);
891 				goto out_err;
892 			}
893 			context = match_strdup(&args[0]);
894 			if (!context) {
895 				rc = -ENOMEM;
896 				goto out_err;
897 			}
898 			break;
899 
900 		case Opt_fscontext:
901 			if (fscontext) {
902 				rc = -EINVAL;
903 				printk(KERN_WARNING SEL_MOUNT_FAIL_MSG);
904 				goto out_err;
905 			}
906 			fscontext = match_strdup(&args[0]);
907 			if (!fscontext) {
908 				rc = -ENOMEM;
909 				goto out_err;
910 			}
911 			break;
912 
913 		case Opt_rootcontext:
914 			if (rootcontext) {
915 				rc = -EINVAL;
916 				printk(KERN_WARNING SEL_MOUNT_FAIL_MSG);
917 				goto out_err;
918 			}
919 			rootcontext = match_strdup(&args[0]);
920 			if (!rootcontext) {
921 				rc = -ENOMEM;
922 				goto out_err;
923 			}
924 			break;
925 
926 		case Opt_defcontext:
927 			if (context || defcontext) {
928 				rc = -EINVAL;
929 				printk(KERN_WARNING SEL_MOUNT_FAIL_MSG);
930 				goto out_err;
931 			}
932 			defcontext = match_strdup(&args[0]);
933 			if (!defcontext) {
934 				rc = -ENOMEM;
935 				goto out_err;
936 			}
937 			break;
938 		case Opt_labelsupport:
939 			break;
940 		default:
941 			rc = -EINVAL;
942 			printk(KERN_WARNING "SELinux:  unknown mount option\n");
943 			goto out_err;
944 
945 		}
946 	}
947 
948 	rc = -ENOMEM;
949 	opts->mnt_opts = kcalloc(NUM_SEL_MNT_OPTS, sizeof(char *), GFP_ATOMIC);
950 	if (!opts->mnt_opts)
951 		goto out_err;
952 
953 	opts->mnt_opts_flags = kcalloc(NUM_SEL_MNT_OPTS, sizeof(int), GFP_ATOMIC);
954 	if (!opts->mnt_opts_flags) {
955 		kfree(opts->mnt_opts);
956 		goto out_err;
957 	}
958 
959 	if (fscontext) {
960 		opts->mnt_opts[num_mnt_opts] = fscontext;
961 		opts->mnt_opts_flags[num_mnt_opts++] = FSCONTEXT_MNT;
962 	}
963 	if (context) {
964 		opts->mnt_opts[num_mnt_opts] = context;
965 		opts->mnt_opts_flags[num_mnt_opts++] = CONTEXT_MNT;
966 	}
967 	if (rootcontext) {
968 		opts->mnt_opts[num_mnt_opts] = rootcontext;
969 		opts->mnt_opts_flags[num_mnt_opts++] = ROOTCONTEXT_MNT;
970 	}
971 	if (defcontext) {
972 		opts->mnt_opts[num_mnt_opts] = defcontext;
973 		opts->mnt_opts_flags[num_mnt_opts++] = DEFCONTEXT_MNT;
974 	}
975 
976 	opts->num_mnt_opts = num_mnt_opts;
977 	return 0;
978 
979 out_err:
980 	kfree(context);
981 	kfree(defcontext);
982 	kfree(fscontext);
983 	kfree(rootcontext);
984 	return rc;
985 }
986 /*
987  * string mount options parsing and call set the sbsec
988  */
989 static int superblock_doinit(struct super_block *sb, void *data)
990 {
991 	int rc = 0;
992 	char *options = data;
993 	struct security_mnt_opts opts;
994 
995 	security_init_mnt_opts(&opts);
996 
997 	if (!data)
998 		goto out;
999 
1000 	BUG_ON(sb->s_type->fs_flags & FS_BINARY_MOUNTDATA);
1001 
1002 	rc = selinux_parse_opts_str(options, &opts);
1003 	if (rc)
1004 		goto out_err;
1005 
1006 out:
1007 	rc = selinux_set_mnt_opts(sb, &opts);
1008 
1009 out_err:
1010 	security_free_mnt_opts(&opts);
1011 	return rc;
1012 }
1013 
1014 static void selinux_write_opts(struct seq_file *m,
1015 			       struct security_mnt_opts *opts)
1016 {
1017 	int i;
1018 	char *prefix;
1019 
1020 	for (i = 0; i < opts->num_mnt_opts; i++) {
1021 		char *has_comma;
1022 
1023 		if (opts->mnt_opts[i])
1024 			has_comma = strchr(opts->mnt_opts[i], ',');
1025 		else
1026 			has_comma = NULL;
1027 
1028 		switch (opts->mnt_opts_flags[i]) {
1029 		case CONTEXT_MNT:
1030 			prefix = CONTEXT_STR;
1031 			break;
1032 		case FSCONTEXT_MNT:
1033 			prefix = FSCONTEXT_STR;
1034 			break;
1035 		case ROOTCONTEXT_MNT:
1036 			prefix = ROOTCONTEXT_STR;
1037 			break;
1038 		case DEFCONTEXT_MNT:
1039 			prefix = DEFCONTEXT_STR;
1040 			break;
1041 		case SE_SBLABELSUPP:
1042 			seq_putc(m, ',');
1043 			seq_puts(m, LABELSUPP_STR);
1044 			continue;
1045 		default:
1046 			BUG();
1047 		};
1048 		/* we need a comma before each option */
1049 		seq_putc(m, ',');
1050 		seq_puts(m, prefix);
1051 		if (has_comma)
1052 			seq_putc(m, '\"');
1053 		seq_puts(m, opts->mnt_opts[i]);
1054 		if (has_comma)
1055 			seq_putc(m, '\"');
1056 	}
1057 }
1058 
1059 static int selinux_sb_show_options(struct seq_file *m, struct super_block *sb)
1060 {
1061 	struct security_mnt_opts opts;
1062 	int rc;
1063 
1064 	rc = selinux_get_mnt_opts(sb, &opts);
1065 	if (rc) {
1066 		/* before policy load we may get EINVAL, don't show anything */
1067 		if (rc == -EINVAL)
1068 			rc = 0;
1069 		return rc;
1070 	}
1071 
1072 	selinux_write_opts(m, &opts);
1073 
1074 	security_free_mnt_opts(&opts);
1075 
1076 	return rc;
1077 }
1078 
1079 static inline u16 inode_mode_to_security_class(umode_t mode)
1080 {
1081 	switch (mode & S_IFMT) {
1082 	case S_IFSOCK:
1083 		return SECCLASS_SOCK_FILE;
1084 	case S_IFLNK:
1085 		return SECCLASS_LNK_FILE;
1086 	case S_IFREG:
1087 		return SECCLASS_FILE;
1088 	case S_IFBLK:
1089 		return SECCLASS_BLK_FILE;
1090 	case S_IFDIR:
1091 		return SECCLASS_DIR;
1092 	case S_IFCHR:
1093 		return SECCLASS_CHR_FILE;
1094 	case S_IFIFO:
1095 		return SECCLASS_FIFO_FILE;
1096 
1097 	}
1098 
1099 	return SECCLASS_FILE;
1100 }
1101 
1102 static inline int default_protocol_stream(int protocol)
1103 {
1104 	return (protocol == IPPROTO_IP || protocol == IPPROTO_TCP);
1105 }
1106 
1107 static inline int default_protocol_dgram(int protocol)
1108 {
1109 	return (protocol == IPPROTO_IP || protocol == IPPROTO_UDP);
1110 }
1111 
1112 static inline u16 socket_type_to_security_class(int family, int type, int protocol)
1113 {
1114 	switch (family) {
1115 	case PF_UNIX:
1116 		switch (type) {
1117 		case SOCK_STREAM:
1118 		case SOCK_SEQPACKET:
1119 			return SECCLASS_UNIX_STREAM_SOCKET;
1120 		case SOCK_DGRAM:
1121 			return SECCLASS_UNIX_DGRAM_SOCKET;
1122 		}
1123 		break;
1124 	case PF_INET:
1125 	case PF_INET6:
1126 		switch (type) {
1127 		case SOCK_STREAM:
1128 			if (default_protocol_stream(protocol))
1129 				return SECCLASS_TCP_SOCKET;
1130 			else
1131 				return SECCLASS_RAWIP_SOCKET;
1132 		case SOCK_DGRAM:
1133 			if (default_protocol_dgram(protocol))
1134 				return SECCLASS_UDP_SOCKET;
1135 			else
1136 				return SECCLASS_RAWIP_SOCKET;
1137 		case SOCK_DCCP:
1138 			return SECCLASS_DCCP_SOCKET;
1139 		default:
1140 			return SECCLASS_RAWIP_SOCKET;
1141 		}
1142 		break;
1143 	case PF_NETLINK:
1144 		switch (protocol) {
1145 		case NETLINK_ROUTE:
1146 			return SECCLASS_NETLINK_ROUTE_SOCKET;
1147 		case NETLINK_FIREWALL:
1148 			return SECCLASS_NETLINK_FIREWALL_SOCKET;
1149 		case NETLINK_INET_DIAG:
1150 			return SECCLASS_NETLINK_TCPDIAG_SOCKET;
1151 		case NETLINK_NFLOG:
1152 			return SECCLASS_NETLINK_NFLOG_SOCKET;
1153 		case NETLINK_XFRM:
1154 			return SECCLASS_NETLINK_XFRM_SOCKET;
1155 		case NETLINK_SELINUX:
1156 			return SECCLASS_NETLINK_SELINUX_SOCKET;
1157 		case NETLINK_AUDIT:
1158 			return SECCLASS_NETLINK_AUDIT_SOCKET;
1159 		case NETLINK_IP6_FW:
1160 			return SECCLASS_NETLINK_IP6FW_SOCKET;
1161 		case NETLINK_DNRTMSG:
1162 			return SECCLASS_NETLINK_DNRT_SOCKET;
1163 		case NETLINK_KOBJECT_UEVENT:
1164 			return SECCLASS_NETLINK_KOBJECT_UEVENT_SOCKET;
1165 		default:
1166 			return SECCLASS_NETLINK_SOCKET;
1167 		}
1168 	case PF_PACKET:
1169 		return SECCLASS_PACKET_SOCKET;
1170 	case PF_KEY:
1171 		return SECCLASS_KEY_SOCKET;
1172 	case PF_APPLETALK:
1173 		return SECCLASS_APPLETALK_SOCKET;
1174 	}
1175 
1176 	return SECCLASS_SOCKET;
1177 }
1178 
1179 #ifdef CONFIG_PROC_FS
1180 static int selinux_proc_get_sid(struct proc_dir_entry *de,
1181 				u16 tclass,
1182 				u32 *sid)
1183 {
1184 	int buflen, rc;
1185 	char *buffer, *path, *end;
1186 
1187 	buffer = (char *)__get_free_page(GFP_KERNEL);
1188 	if (!buffer)
1189 		return -ENOMEM;
1190 
1191 	buflen = PAGE_SIZE;
1192 	end = buffer+buflen;
1193 	*--end = '\0';
1194 	buflen--;
1195 	path = end-1;
1196 	*path = '/';
1197 	while (de && de != de->parent) {
1198 		buflen -= de->namelen + 1;
1199 		if (buflen < 0)
1200 			break;
1201 		end -= de->namelen;
1202 		memcpy(end, de->name, de->namelen);
1203 		*--end = '/';
1204 		path = end;
1205 		de = de->parent;
1206 	}
1207 	rc = security_genfs_sid("proc", path, tclass, sid);
1208 	free_page((unsigned long)buffer);
1209 	return rc;
1210 }
1211 #else
1212 static int selinux_proc_get_sid(struct proc_dir_entry *de,
1213 				u16 tclass,
1214 				u32 *sid)
1215 {
1216 	return -EINVAL;
1217 }
1218 #endif
1219 
1220 /* The inode's security attributes must be initialized before first use. */
1221 static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dentry)
1222 {
1223 	struct superblock_security_struct *sbsec = NULL;
1224 	struct inode_security_struct *isec = inode->i_security;
1225 	u32 sid;
1226 	struct dentry *dentry;
1227 #define INITCONTEXTLEN 255
1228 	char *context = NULL;
1229 	unsigned len = 0;
1230 	int rc = 0;
1231 
1232 	if (isec->initialized)
1233 		goto out;
1234 
1235 	mutex_lock(&isec->lock);
1236 	if (isec->initialized)
1237 		goto out_unlock;
1238 
1239 	sbsec = inode->i_sb->s_security;
1240 	if (!(sbsec->flags & SE_SBINITIALIZED)) {
1241 		/* Defer initialization until selinux_complete_init,
1242 		   after the initial policy is loaded and the security
1243 		   server is ready to handle calls. */
1244 		spin_lock(&sbsec->isec_lock);
1245 		if (list_empty(&isec->list))
1246 			list_add(&isec->list, &sbsec->isec_head);
1247 		spin_unlock(&sbsec->isec_lock);
1248 		goto out_unlock;
1249 	}
1250 
1251 	switch (sbsec->behavior) {
1252 	case SECURITY_FS_USE_XATTR:
1253 		if (!inode->i_op->getxattr) {
1254 			isec->sid = sbsec->def_sid;
1255 			break;
1256 		}
1257 
1258 		/* Need a dentry, since the xattr API requires one.
1259 		   Life would be simpler if we could just pass the inode. */
1260 		if (opt_dentry) {
1261 			/* Called from d_instantiate or d_splice_alias. */
1262 			dentry = dget(opt_dentry);
1263 		} else {
1264 			/* Called from selinux_complete_init, try to find a dentry. */
1265 			dentry = d_find_alias(inode);
1266 		}
1267 		if (!dentry) {
1268 			/*
1269 			 * this is can be hit on boot when a file is accessed
1270 			 * before the policy is loaded.  When we load policy we
1271 			 * may find inodes that have no dentry on the
1272 			 * sbsec->isec_head list.  No reason to complain as these
1273 			 * will get fixed up the next time we go through
1274 			 * inode_doinit with a dentry, before these inodes could
1275 			 * be used again by userspace.
1276 			 */
1277 			goto out_unlock;
1278 		}
1279 
1280 		len = INITCONTEXTLEN;
1281 		context = kmalloc(len+1, GFP_NOFS);
1282 		if (!context) {
1283 			rc = -ENOMEM;
1284 			dput(dentry);
1285 			goto out_unlock;
1286 		}
1287 		context[len] = '\0';
1288 		rc = inode->i_op->getxattr(dentry, XATTR_NAME_SELINUX,
1289 					   context, len);
1290 		if (rc == -ERANGE) {
1291 			kfree(context);
1292 
1293 			/* Need a larger buffer.  Query for the right size. */
1294 			rc = inode->i_op->getxattr(dentry, XATTR_NAME_SELINUX,
1295 						   NULL, 0);
1296 			if (rc < 0) {
1297 				dput(dentry);
1298 				goto out_unlock;
1299 			}
1300 			len = rc;
1301 			context = kmalloc(len+1, GFP_NOFS);
1302 			if (!context) {
1303 				rc = -ENOMEM;
1304 				dput(dentry);
1305 				goto out_unlock;
1306 			}
1307 			context[len] = '\0';
1308 			rc = inode->i_op->getxattr(dentry,
1309 						   XATTR_NAME_SELINUX,
1310 						   context, len);
1311 		}
1312 		dput(dentry);
1313 		if (rc < 0) {
1314 			if (rc != -ENODATA) {
1315 				printk(KERN_WARNING "SELinux: %s:  getxattr returned "
1316 				       "%d for dev=%s ino=%ld\n", __func__,
1317 				       -rc, inode->i_sb->s_id, inode->i_ino);
1318 				kfree(context);
1319 				goto out_unlock;
1320 			}
1321 			/* Map ENODATA to the default file SID */
1322 			sid = sbsec->def_sid;
1323 			rc = 0;
1324 		} else {
1325 			rc = security_context_to_sid_default(context, rc, &sid,
1326 							     sbsec->def_sid,
1327 							     GFP_NOFS);
1328 			if (rc) {
1329 				char *dev = inode->i_sb->s_id;
1330 				unsigned long ino = inode->i_ino;
1331 
1332 				if (rc == -EINVAL) {
1333 					if (printk_ratelimit())
1334 						printk(KERN_NOTICE "SELinux: inode=%lu on dev=%s was found to have an invalid "
1335 							"context=%s.  This indicates you may need to relabel the inode or the "
1336 							"filesystem in question.\n", ino, dev, context);
1337 				} else {
1338 					printk(KERN_WARNING "SELinux: %s:  context_to_sid(%s) "
1339 					       "returned %d for dev=%s ino=%ld\n",
1340 					       __func__, context, -rc, dev, ino);
1341 				}
1342 				kfree(context);
1343 				/* Leave with the unlabeled SID */
1344 				rc = 0;
1345 				break;
1346 			}
1347 		}
1348 		kfree(context);
1349 		isec->sid = sid;
1350 		break;
1351 	case SECURITY_FS_USE_TASK:
1352 		isec->sid = isec->task_sid;
1353 		break;
1354 	case SECURITY_FS_USE_TRANS:
1355 		/* Default to the fs SID. */
1356 		isec->sid = sbsec->sid;
1357 
1358 		/* Try to obtain a transition SID. */
1359 		isec->sclass = inode_mode_to_security_class(inode->i_mode);
1360 		rc = security_transition_sid(isec->task_sid,
1361 					     sbsec->sid,
1362 					     isec->sclass,
1363 					     &sid);
1364 		if (rc)
1365 			goto out_unlock;
1366 		isec->sid = sid;
1367 		break;
1368 	case SECURITY_FS_USE_MNTPOINT:
1369 		isec->sid = sbsec->mntpoint_sid;
1370 		break;
1371 	default:
1372 		/* Default to the fs superblock SID. */
1373 		isec->sid = sbsec->sid;
1374 
1375 		if ((sbsec->flags & SE_SBPROC) && !S_ISLNK(inode->i_mode)) {
1376 			struct proc_inode *proci = PROC_I(inode);
1377 			if (proci->pde) {
1378 				isec->sclass = inode_mode_to_security_class(inode->i_mode);
1379 				rc = selinux_proc_get_sid(proci->pde,
1380 							  isec->sclass,
1381 							  &sid);
1382 				if (rc)
1383 					goto out_unlock;
1384 				isec->sid = sid;
1385 			}
1386 		}
1387 		break;
1388 	}
1389 
1390 	isec->initialized = 1;
1391 
1392 out_unlock:
1393 	mutex_unlock(&isec->lock);
1394 out:
1395 	if (isec->sclass == SECCLASS_FILE)
1396 		isec->sclass = inode_mode_to_security_class(inode->i_mode);
1397 	return rc;
1398 }
1399 
1400 /* Convert a Linux signal to an access vector. */
1401 static inline u32 signal_to_av(int sig)
1402 {
1403 	u32 perm = 0;
1404 
1405 	switch (sig) {
1406 	case SIGCHLD:
1407 		/* Commonly granted from child to parent. */
1408 		perm = PROCESS__SIGCHLD;
1409 		break;
1410 	case SIGKILL:
1411 		/* Cannot be caught or ignored */
1412 		perm = PROCESS__SIGKILL;
1413 		break;
1414 	case SIGSTOP:
1415 		/* Cannot be caught or ignored */
1416 		perm = PROCESS__SIGSTOP;
1417 		break;
1418 	default:
1419 		/* All other signals. */
1420 		perm = PROCESS__SIGNAL;
1421 		break;
1422 	}
1423 
1424 	return perm;
1425 }
1426 
1427 /*
1428  * Check permission between a pair of credentials
1429  * fork check, ptrace check, etc.
1430  */
1431 static int cred_has_perm(const struct cred *actor,
1432 			 const struct cred *target,
1433 			 u32 perms)
1434 {
1435 	u32 asid = cred_sid(actor), tsid = cred_sid(target);
1436 
1437 	return avc_has_perm(asid, tsid, SECCLASS_PROCESS, perms, NULL);
1438 }
1439 
1440 /*
1441  * Check permission between a pair of tasks, e.g. signal checks,
1442  * fork check, ptrace check, etc.
1443  * tsk1 is the actor and tsk2 is the target
1444  * - this uses the default subjective creds of tsk1
1445  */
1446 static int task_has_perm(const struct task_struct *tsk1,
1447 			 const struct task_struct *tsk2,
1448 			 u32 perms)
1449 {
1450 	const struct task_security_struct *__tsec1, *__tsec2;
1451 	u32 sid1, sid2;
1452 
1453 	rcu_read_lock();
1454 	__tsec1 = __task_cred(tsk1)->security;	sid1 = __tsec1->sid;
1455 	__tsec2 = __task_cred(tsk2)->security;	sid2 = __tsec2->sid;
1456 	rcu_read_unlock();
1457 	return avc_has_perm(sid1, sid2, SECCLASS_PROCESS, perms, NULL);
1458 }
1459 
1460 /*
1461  * Check permission between current and another task, e.g. signal checks,
1462  * fork check, ptrace check, etc.
1463  * current is the actor and tsk2 is the target
1464  * - this uses current's subjective creds
1465  */
1466 static int current_has_perm(const struct task_struct *tsk,
1467 			    u32 perms)
1468 {
1469 	u32 sid, tsid;
1470 
1471 	sid = current_sid();
1472 	tsid = task_sid(tsk);
1473 	return avc_has_perm(sid, tsid, SECCLASS_PROCESS, perms, NULL);
1474 }
1475 
1476 #if CAP_LAST_CAP > 63
1477 #error Fix SELinux to handle capabilities > 63.
1478 #endif
1479 
1480 /* Check whether a task is allowed to use a capability. */
1481 static int task_has_capability(struct task_struct *tsk,
1482 			       const struct cred *cred,
1483 			       int cap, int audit)
1484 {
1485 	struct common_audit_data ad;
1486 	struct av_decision avd;
1487 	u16 sclass;
1488 	u32 sid = cred_sid(cred);
1489 	u32 av = CAP_TO_MASK(cap);
1490 	int rc;
1491 
1492 	COMMON_AUDIT_DATA_INIT(&ad, CAP);
1493 	ad.tsk = tsk;
1494 	ad.u.cap = cap;
1495 
1496 	switch (CAP_TO_INDEX(cap)) {
1497 	case 0:
1498 		sclass = SECCLASS_CAPABILITY;
1499 		break;
1500 	case 1:
1501 		sclass = SECCLASS_CAPABILITY2;
1502 		break;
1503 	default:
1504 		printk(KERN_ERR
1505 		       "SELinux:  out of range capability %d\n", cap);
1506 		BUG();
1507 	}
1508 
1509 	rc = avc_has_perm_noaudit(sid, sid, sclass, av, 0, &avd);
1510 	if (audit == SECURITY_CAP_AUDIT)
1511 		avc_audit(sid, sid, sclass, av, &avd, rc, &ad);
1512 	return rc;
1513 }
1514 
1515 /* Check whether a task is allowed to use a system operation. */
1516 static int task_has_system(struct task_struct *tsk,
1517 			   u32 perms)
1518 {
1519 	u32 sid = task_sid(tsk);
1520 
1521 	return avc_has_perm(sid, SECINITSID_KERNEL,
1522 			    SECCLASS_SYSTEM, perms, NULL);
1523 }
1524 
1525 /* Check whether a task has a particular permission to an inode.
1526    The 'adp' parameter is optional and allows other audit
1527    data to be passed (e.g. the dentry). */
1528 static int inode_has_perm(const struct cred *cred,
1529 			  struct inode *inode,
1530 			  u32 perms,
1531 			  struct common_audit_data *adp)
1532 {
1533 	struct inode_security_struct *isec;
1534 	struct common_audit_data ad;
1535 	u32 sid;
1536 
1537 	validate_creds(cred);
1538 
1539 	if (unlikely(IS_PRIVATE(inode)))
1540 		return 0;
1541 
1542 	sid = cred_sid(cred);
1543 	isec = inode->i_security;
1544 
1545 	if (!adp) {
1546 		adp = &ad;
1547 		COMMON_AUDIT_DATA_INIT(&ad, FS);
1548 		ad.u.fs.inode = inode;
1549 	}
1550 
1551 	return avc_has_perm(sid, isec->sid, isec->sclass, perms, adp);
1552 }
1553 
1554 /* Same as inode_has_perm, but pass explicit audit data containing
1555    the dentry to help the auditing code to more easily generate the
1556    pathname if needed. */
1557 static inline int dentry_has_perm(const struct cred *cred,
1558 				  struct vfsmount *mnt,
1559 				  struct dentry *dentry,
1560 				  u32 av)
1561 {
1562 	struct inode *inode = dentry->d_inode;
1563 	struct common_audit_data ad;
1564 
1565 	COMMON_AUDIT_DATA_INIT(&ad, FS);
1566 	ad.u.fs.path.mnt = mnt;
1567 	ad.u.fs.path.dentry = dentry;
1568 	return inode_has_perm(cred, inode, av, &ad);
1569 }
1570 
1571 /* Check whether a task can use an open file descriptor to
1572    access an inode in a given way.  Check access to the
1573    descriptor itself, and then use dentry_has_perm to
1574    check a particular permission to the file.
1575    Access to the descriptor is implicitly granted if it
1576    has the same SID as the process.  If av is zero, then
1577    access to the file is not checked, e.g. for cases
1578    where only the descriptor is affected like seek. */
1579 static int file_has_perm(const struct cred *cred,
1580 			 struct file *file,
1581 			 u32 av)
1582 {
1583 	struct file_security_struct *fsec = file->f_security;
1584 	struct inode *inode = file->f_path.dentry->d_inode;
1585 	struct common_audit_data ad;
1586 	u32 sid = cred_sid(cred);
1587 	int rc;
1588 
1589 	COMMON_AUDIT_DATA_INIT(&ad, FS);
1590 	ad.u.fs.path = file->f_path;
1591 
1592 	if (sid != fsec->sid) {
1593 		rc = avc_has_perm(sid, fsec->sid,
1594 				  SECCLASS_FD,
1595 				  FD__USE,
1596 				  &ad);
1597 		if (rc)
1598 			goto out;
1599 	}
1600 
1601 	/* av is zero if only checking access to the descriptor. */
1602 	rc = 0;
1603 	if (av)
1604 		rc = inode_has_perm(cred, inode, av, &ad);
1605 
1606 out:
1607 	return rc;
1608 }
1609 
1610 /* Check whether a task can create a file. */
1611 static int may_create(struct inode *dir,
1612 		      struct dentry *dentry,
1613 		      u16 tclass)
1614 {
1615 	const struct cred *cred = current_cred();
1616 	const struct task_security_struct *tsec = cred->security;
1617 	struct inode_security_struct *dsec;
1618 	struct superblock_security_struct *sbsec;
1619 	u32 sid, newsid;
1620 	struct common_audit_data ad;
1621 	int rc;
1622 
1623 	dsec = dir->i_security;
1624 	sbsec = dir->i_sb->s_security;
1625 
1626 	sid = tsec->sid;
1627 	newsid = tsec->create_sid;
1628 
1629 	COMMON_AUDIT_DATA_INIT(&ad, FS);
1630 	ad.u.fs.path.dentry = dentry;
1631 
1632 	rc = avc_has_perm(sid, dsec->sid, SECCLASS_DIR,
1633 			  DIR__ADD_NAME | DIR__SEARCH,
1634 			  &ad);
1635 	if (rc)
1636 		return rc;
1637 
1638 	if (!newsid || !(sbsec->flags & SE_SBLABELSUPP)) {
1639 		rc = security_transition_sid(sid, dsec->sid, tclass, &newsid);
1640 		if (rc)
1641 			return rc;
1642 	}
1643 
1644 	rc = avc_has_perm(sid, newsid, tclass, FILE__CREATE, &ad);
1645 	if (rc)
1646 		return rc;
1647 
1648 	return avc_has_perm(newsid, sbsec->sid,
1649 			    SECCLASS_FILESYSTEM,
1650 			    FILESYSTEM__ASSOCIATE, &ad);
1651 }
1652 
1653 /* Check whether a task can create a key. */
1654 static int may_create_key(u32 ksid,
1655 			  struct task_struct *ctx)
1656 {
1657 	u32 sid = task_sid(ctx);
1658 
1659 	return avc_has_perm(sid, ksid, SECCLASS_KEY, KEY__CREATE, NULL);
1660 }
1661 
1662 #define MAY_LINK	0
1663 #define MAY_UNLINK	1
1664 #define MAY_RMDIR	2
1665 
1666 /* Check whether a task can link, unlink, or rmdir a file/directory. */
1667 static int may_link(struct inode *dir,
1668 		    struct dentry *dentry,
1669 		    int kind)
1670 
1671 {
1672 	struct inode_security_struct *dsec, *isec;
1673 	struct common_audit_data ad;
1674 	u32 sid = current_sid();
1675 	u32 av;
1676 	int rc;
1677 
1678 	dsec = dir->i_security;
1679 	isec = dentry->d_inode->i_security;
1680 
1681 	COMMON_AUDIT_DATA_INIT(&ad, FS);
1682 	ad.u.fs.path.dentry = dentry;
1683 
1684 	av = DIR__SEARCH;
1685 	av |= (kind ? DIR__REMOVE_NAME : DIR__ADD_NAME);
1686 	rc = avc_has_perm(sid, dsec->sid, SECCLASS_DIR, av, &ad);
1687 	if (rc)
1688 		return rc;
1689 
1690 	switch (kind) {
1691 	case MAY_LINK:
1692 		av = FILE__LINK;
1693 		break;
1694 	case MAY_UNLINK:
1695 		av = FILE__UNLINK;
1696 		break;
1697 	case MAY_RMDIR:
1698 		av = DIR__RMDIR;
1699 		break;
1700 	default:
1701 		printk(KERN_WARNING "SELinux: %s:  unrecognized kind %d\n",
1702 			__func__, kind);
1703 		return 0;
1704 	}
1705 
1706 	rc = avc_has_perm(sid, isec->sid, isec->sclass, av, &ad);
1707 	return rc;
1708 }
1709 
1710 static inline int may_rename(struct inode *old_dir,
1711 			     struct dentry *old_dentry,
1712 			     struct inode *new_dir,
1713 			     struct dentry *new_dentry)
1714 {
1715 	struct inode_security_struct *old_dsec, *new_dsec, *old_isec, *new_isec;
1716 	struct common_audit_data ad;
1717 	u32 sid = current_sid();
1718 	u32 av;
1719 	int old_is_dir, new_is_dir;
1720 	int rc;
1721 
1722 	old_dsec = old_dir->i_security;
1723 	old_isec = old_dentry->d_inode->i_security;
1724 	old_is_dir = S_ISDIR(old_dentry->d_inode->i_mode);
1725 	new_dsec = new_dir->i_security;
1726 
1727 	COMMON_AUDIT_DATA_INIT(&ad, FS);
1728 
1729 	ad.u.fs.path.dentry = old_dentry;
1730 	rc = avc_has_perm(sid, old_dsec->sid, SECCLASS_DIR,
1731 			  DIR__REMOVE_NAME | DIR__SEARCH, &ad);
1732 	if (rc)
1733 		return rc;
1734 	rc = avc_has_perm(sid, old_isec->sid,
1735 			  old_isec->sclass, FILE__RENAME, &ad);
1736 	if (rc)
1737 		return rc;
1738 	if (old_is_dir && new_dir != old_dir) {
1739 		rc = avc_has_perm(sid, old_isec->sid,
1740 				  old_isec->sclass, DIR__REPARENT, &ad);
1741 		if (rc)
1742 			return rc;
1743 	}
1744 
1745 	ad.u.fs.path.dentry = new_dentry;
1746 	av = DIR__ADD_NAME | DIR__SEARCH;
1747 	if (new_dentry->d_inode)
1748 		av |= DIR__REMOVE_NAME;
1749 	rc = avc_has_perm(sid, new_dsec->sid, SECCLASS_DIR, av, &ad);
1750 	if (rc)
1751 		return rc;
1752 	if (new_dentry->d_inode) {
1753 		new_isec = new_dentry->d_inode->i_security;
1754 		new_is_dir = S_ISDIR(new_dentry->d_inode->i_mode);
1755 		rc = avc_has_perm(sid, new_isec->sid,
1756 				  new_isec->sclass,
1757 				  (new_is_dir ? DIR__RMDIR : FILE__UNLINK), &ad);
1758 		if (rc)
1759 			return rc;
1760 	}
1761 
1762 	return 0;
1763 }
1764 
1765 /* Check whether a task can perform a filesystem operation. */
1766 static int superblock_has_perm(const struct cred *cred,
1767 			       struct super_block *sb,
1768 			       u32 perms,
1769 			       struct common_audit_data *ad)
1770 {
1771 	struct superblock_security_struct *sbsec;
1772 	u32 sid = cred_sid(cred);
1773 
1774 	sbsec = sb->s_security;
1775 	return avc_has_perm(sid, sbsec->sid, SECCLASS_FILESYSTEM, perms, ad);
1776 }
1777 
1778 /* Convert a Linux mode and permission mask to an access vector. */
1779 static inline u32 file_mask_to_av(int mode, int mask)
1780 {
1781 	u32 av = 0;
1782 
1783 	if ((mode & S_IFMT) != S_IFDIR) {
1784 		if (mask & MAY_EXEC)
1785 			av |= FILE__EXECUTE;
1786 		if (mask & MAY_READ)
1787 			av |= FILE__READ;
1788 
1789 		if (mask & MAY_APPEND)
1790 			av |= FILE__APPEND;
1791 		else if (mask & MAY_WRITE)
1792 			av |= FILE__WRITE;
1793 
1794 	} else {
1795 		if (mask & MAY_EXEC)
1796 			av |= DIR__SEARCH;
1797 		if (mask & MAY_WRITE)
1798 			av |= DIR__WRITE;
1799 		if (mask & MAY_READ)
1800 			av |= DIR__READ;
1801 	}
1802 
1803 	return av;
1804 }
1805 
1806 /* Convert a Linux file to an access vector. */
1807 static inline u32 file_to_av(struct file *file)
1808 {
1809 	u32 av = 0;
1810 
1811 	if (file->f_mode & FMODE_READ)
1812 		av |= FILE__READ;
1813 	if (file->f_mode & FMODE_WRITE) {
1814 		if (file->f_flags & O_APPEND)
1815 			av |= FILE__APPEND;
1816 		else
1817 			av |= FILE__WRITE;
1818 	}
1819 	if (!av) {
1820 		/*
1821 		 * Special file opened with flags 3 for ioctl-only use.
1822 		 */
1823 		av = FILE__IOCTL;
1824 	}
1825 
1826 	return av;
1827 }
1828 
1829 /*
1830  * Convert a file to an access vector and include the correct open
1831  * open permission.
1832  */
1833 static inline u32 open_file_to_av(struct file *file)
1834 {
1835 	u32 av = file_to_av(file);
1836 
1837 	if (selinux_policycap_openperm) {
1838 		mode_t mode = file->f_path.dentry->d_inode->i_mode;
1839 		/*
1840 		 * lnk files and socks do not really have an 'open'
1841 		 */
1842 		if (S_ISREG(mode))
1843 			av |= FILE__OPEN;
1844 		else if (S_ISCHR(mode))
1845 			av |= CHR_FILE__OPEN;
1846 		else if (S_ISBLK(mode))
1847 			av |= BLK_FILE__OPEN;
1848 		else if (S_ISFIFO(mode))
1849 			av |= FIFO_FILE__OPEN;
1850 		else if (S_ISDIR(mode))
1851 			av |= DIR__OPEN;
1852 		else if (S_ISSOCK(mode))
1853 			av |= SOCK_FILE__OPEN;
1854 		else
1855 			printk(KERN_ERR "SELinux: WARNING: inside %s with "
1856 				"unknown mode:%o\n", __func__, mode);
1857 	}
1858 	return av;
1859 }
1860 
1861 /* Hook functions begin here. */
1862 
1863 static int selinux_ptrace_access_check(struct task_struct *child,
1864 				     unsigned int mode)
1865 {
1866 	int rc;
1867 
1868 	rc = cap_ptrace_access_check(child, mode);
1869 	if (rc)
1870 		return rc;
1871 
1872 	if (mode == PTRACE_MODE_READ) {
1873 		u32 sid = current_sid();
1874 		u32 csid = task_sid(child);
1875 		return avc_has_perm(sid, csid, SECCLASS_FILE, FILE__READ, NULL);
1876 	}
1877 
1878 	return current_has_perm(child, PROCESS__PTRACE);
1879 }
1880 
1881 static int selinux_ptrace_traceme(struct task_struct *parent)
1882 {
1883 	int rc;
1884 
1885 	rc = cap_ptrace_traceme(parent);
1886 	if (rc)
1887 		return rc;
1888 
1889 	return task_has_perm(parent, current, PROCESS__PTRACE);
1890 }
1891 
1892 static int selinux_capget(struct task_struct *target, kernel_cap_t *effective,
1893 			  kernel_cap_t *inheritable, kernel_cap_t *permitted)
1894 {
1895 	int error;
1896 
1897 	error = current_has_perm(target, PROCESS__GETCAP);
1898 	if (error)
1899 		return error;
1900 
1901 	return cap_capget(target, effective, inheritable, permitted);
1902 }
1903 
1904 static int selinux_capset(struct cred *new, const struct cred *old,
1905 			  const kernel_cap_t *effective,
1906 			  const kernel_cap_t *inheritable,
1907 			  const kernel_cap_t *permitted)
1908 {
1909 	int error;
1910 
1911 	error = cap_capset(new, old,
1912 				      effective, inheritable, permitted);
1913 	if (error)
1914 		return error;
1915 
1916 	return cred_has_perm(old, new, PROCESS__SETCAP);
1917 }
1918 
1919 /*
1920  * (This comment used to live with the selinux_task_setuid hook,
1921  * which was removed).
1922  *
1923  * Since setuid only affects the current process, and since the SELinux
1924  * controls are not based on the Linux identity attributes, SELinux does not
1925  * need to control this operation.  However, SELinux does control the use of
1926  * the CAP_SETUID and CAP_SETGID capabilities using the capable hook.
1927  */
1928 
1929 static int selinux_capable(struct task_struct *tsk, const struct cred *cred,
1930 			   int cap, int audit)
1931 {
1932 	int rc;
1933 
1934 	rc = cap_capable(tsk, cred, cap, audit);
1935 	if (rc)
1936 		return rc;
1937 
1938 	return task_has_capability(tsk, cred, cap, audit);
1939 }
1940 
1941 static int selinux_sysctl_get_sid(ctl_table *table, u16 tclass, u32 *sid)
1942 {
1943 	int buflen, rc;
1944 	char *buffer, *path, *end;
1945 
1946 	rc = -ENOMEM;
1947 	buffer = (char *)__get_free_page(GFP_KERNEL);
1948 	if (!buffer)
1949 		goto out;
1950 
1951 	buflen = PAGE_SIZE;
1952 	end = buffer+buflen;
1953 	*--end = '\0';
1954 	buflen--;
1955 	path = end-1;
1956 	*path = '/';
1957 	while (table) {
1958 		const char *name = table->procname;
1959 		size_t namelen = strlen(name);
1960 		buflen -= namelen + 1;
1961 		if (buflen < 0)
1962 			goto out_free;
1963 		end -= namelen;
1964 		memcpy(end, name, namelen);
1965 		*--end = '/';
1966 		path = end;
1967 		table = table->parent;
1968 	}
1969 	buflen -= 4;
1970 	if (buflen < 0)
1971 		goto out_free;
1972 	end -= 4;
1973 	memcpy(end, "/sys", 4);
1974 	path = end;
1975 	rc = security_genfs_sid("proc", path, tclass, sid);
1976 out_free:
1977 	free_page((unsigned long)buffer);
1978 out:
1979 	return rc;
1980 }
1981 
1982 static int selinux_sysctl(ctl_table *table, int op)
1983 {
1984 	int error = 0;
1985 	u32 av;
1986 	u32 tsid, sid;
1987 	int rc;
1988 
1989 	sid = current_sid();
1990 
1991 	rc = selinux_sysctl_get_sid(table, (op == 0001) ?
1992 				    SECCLASS_DIR : SECCLASS_FILE, &tsid);
1993 	if (rc) {
1994 		/* Default to the well-defined sysctl SID. */
1995 		tsid = SECINITSID_SYSCTL;
1996 	}
1997 
1998 	/* The op values are "defined" in sysctl.c, thereby creating
1999 	 * a bad coupling between this module and sysctl.c */
2000 	if (op == 001) {
2001 		error = avc_has_perm(sid, tsid,
2002 				     SECCLASS_DIR, DIR__SEARCH, NULL);
2003 	} else {
2004 		av = 0;
2005 		if (op & 004)
2006 			av |= FILE__READ;
2007 		if (op & 002)
2008 			av |= FILE__WRITE;
2009 		if (av)
2010 			error = avc_has_perm(sid, tsid,
2011 					     SECCLASS_FILE, av, NULL);
2012 	}
2013 
2014 	return error;
2015 }
2016 
2017 static int selinux_quotactl(int cmds, int type, int id, struct super_block *sb)
2018 {
2019 	const struct cred *cred = current_cred();
2020 	int rc = 0;
2021 
2022 	if (!sb)
2023 		return 0;
2024 
2025 	switch (cmds) {
2026 	case Q_SYNC:
2027 	case Q_QUOTAON:
2028 	case Q_QUOTAOFF:
2029 	case Q_SETINFO:
2030 	case Q_SETQUOTA:
2031 		rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAMOD, NULL);
2032 		break;
2033 	case Q_GETFMT:
2034 	case Q_GETINFO:
2035 	case Q_GETQUOTA:
2036 		rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAGET, NULL);
2037 		break;
2038 	default:
2039 		rc = 0;  /* let the kernel handle invalid cmds */
2040 		break;
2041 	}
2042 	return rc;
2043 }
2044 
2045 static int selinux_quota_on(struct dentry *dentry)
2046 {
2047 	const struct cred *cred = current_cred();
2048 
2049 	return dentry_has_perm(cred, NULL, dentry, FILE__QUOTAON);
2050 }
2051 
2052 static int selinux_syslog(int type)
2053 {
2054 	int rc;
2055 
2056 	rc = cap_syslog(type);
2057 	if (rc)
2058 		return rc;
2059 
2060 	switch (type) {
2061 	case 3:		/* Read last kernel messages */
2062 	case 10:	/* Return size of the log buffer */
2063 		rc = task_has_system(current, SYSTEM__SYSLOG_READ);
2064 		break;
2065 	case 6:		/* Disable logging to console */
2066 	case 7:		/* Enable logging to console */
2067 	case 8:		/* Set level of messages printed to console */
2068 		rc = task_has_system(current, SYSTEM__SYSLOG_CONSOLE);
2069 		break;
2070 	case 0:		/* Close log */
2071 	case 1:		/* Open log */
2072 	case 2:		/* Read from log */
2073 	case 4:		/* Read/clear last kernel messages */
2074 	case 5:		/* Clear ring buffer */
2075 	default:
2076 		rc = task_has_system(current, SYSTEM__SYSLOG_MOD);
2077 		break;
2078 	}
2079 	return rc;
2080 }
2081 
2082 /*
2083  * Check that a process has enough memory to allocate a new virtual
2084  * mapping. 0 means there is enough memory for the allocation to
2085  * succeed and -ENOMEM implies there is not.
2086  *
2087  * Do not audit the selinux permission check, as this is applied to all
2088  * processes that allocate mappings.
2089  */
2090 static int selinux_vm_enough_memory(struct mm_struct *mm, long pages)
2091 {
2092 	int rc, cap_sys_admin = 0;
2093 
2094 	rc = selinux_capable(current, current_cred(), CAP_SYS_ADMIN,
2095 			     SECURITY_CAP_NOAUDIT);
2096 	if (rc == 0)
2097 		cap_sys_admin = 1;
2098 
2099 	return __vm_enough_memory(mm, pages, cap_sys_admin);
2100 }
2101 
2102 /* binprm security operations */
2103 
2104 static int selinux_bprm_set_creds(struct linux_binprm *bprm)
2105 {
2106 	const struct task_security_struct *old_tsec;
2107 	struct task_security_struct *new_tsec;
2108 	struct inode_security_struct *isec;
2109 	struct common_audit_data ad;
2110 	struct inode *inode = bprm->file->f_path.dentry->d_inode;
2111 	int rc;
2112 
2113 	rc = cap_bprm_set_creds(bprm);
2114 	if (rc)
2115 		return rc;
2116 
2117 	/* SELinux context only depends on initial program or script and not
2118 	 * the script interpreter */
2119 	if (bprm->cred_prepared)
2120 		return 0;
2121 
2122 	old_tsec = current_security();
2123 	new_tsec = bprm->cred->security;
2124 	isec = inode->i_security;
2125 
2126 	/* Default to the current task SID. */
2127 	new_tsec->sid = old_tsec->sid;
2128 	new_tsec->osid = old_tsec->sid;
2129 
2130 	/* Reset fs, key, and sock SIDs on execve. */
2131 	new_tsec->create_sid = 0;
2132 	new_tsec->keycreate_sid = 0;
2133 	new_tsec->sockcreate_sid = 0;
2134 
2135 	if (old_tsec->exec_sid) {
2136 		new_tsec->sid = old_tsec->exec_sid;
2137 		/* Reset exec SID on execve. */
2138 		new_tsec->exec_sid = 0;
2139 	} else {
2140 		/* Check for a default transition on this program. */
2141 		rc = security_transition_sid(old_tsec->sid, isec->sid,
2142 					     SECCLASS_PROCESS, &new_tsec->sid);
2143 		if (rc)
2144 			return rc;
2145 	}
2146 
2147 	COMMON_AUDIT_DATA_INIT(&ad, FS);
2148 	ad.u.fs.path = bprm->file->f_path;
2149 
2150 	if (bprm->file->f_path.mnt->mnt_flags & MNT_NOSUID)
2151 		new_tsec->sid = old_tsec->sid;
2152 
2153 	if (new_tsec->sid == old_tsec->sid) {
2154 		rc = avc_has_perm(old_tsec->sid, isec->sid,
2155 				  SECCLASS_FILE, FILE__EXECUTE_NO_TRANS, &ad);
2156 		if (rc)
2157 			return rc;
2158 	} else {
2159 		/* Check permissions for the transition. */
2160 		rc = avc_has_perm(old_tsec->sid, new_tsec->sid,
2161 				  SECCLASS_PROCESS, PROCESS__TRANSITION, &ad);
2162 		if (rc)
2163 			return rc;
2164 
2165 		rc = avc_has_perm(new_tsec->sid, isec->sid,
2166 				  SECCLASS_FILE, FILE__ENTRYPOINT, &ad);
2167 		if (rc)
2168 			return rc;
2169 
2170 		/* Check for shared state */
2171 		if (bprm->unsafe & LSM_UNSAFE_SHARE) {
2172 			rc = avc_has_perm(old_tsec->sid, new_tsec->sid,
2173 					  SECCLASS_PROCESS, PROCESS__SHARE,
2174 					  NULL);
2175 			if (rc)
2176 				return -EPERM;
2177 		}
2178 
2179 		/* Make sure that anyone attempting to ptrace over a task that
2180 		 * changes its SID has the appropriate permit */
2181 		if (bprm->unsafe &
2182 		    (LSM_UNSAFE_PTRACE | LSM_UNSAFE_PTRACE_CAP)) {
2183 			struct task_struct *tracer;
2184 			struct task_security_struct *sec;
2185 			u32 ptsid = 0;
2186 
2187 			rcu_read_lock();
2188 			tracer = tracehook_tracer_task(current);
2189 			if (likely(tracer != NULL)) {
2190 				sec = __task_cred(tracer)->security;
2191 				ptsid = sec->sid;
2192 			}
2193 			rcu_read_unlock();
2194 
2195 			if (ptsid != 0) {
2196 				rc = avc_has_perm(ptsid, new_tsec->sid,
2197 						  SECCLASS_PROCESS,
2198 						  PROCESS__PTRACE, NULL);
2199 				if (rc)
2200 					return -EPERM;
2201 			}
2202 		}
2203 
2204 		/* Clear any possibly unsafe personality bits on exec: */
2205 		bprm->per_clear |= PER_CLEAR_ON_SETID;
2206 	}
2207 
2208 	return 0;
2209 }
2210 
2211 static int selinux_bprm_secureexec(struct linux_binprm *bprm)
2212 {
2213 	const struct cred *cred = current_cred();
2214 	const struct task_security_struct *tsec = cred->security;
2215 	u32 sid, osid;
2216 	int atsecure = 0;
2217 
2218 	sid = tsec->sid;
2219 	osid = tsec->osid;
2220 
2221 	if (osid != sid) {
2222 		/* Enable secure mode for SIDs transitions unless
2223 		   the noatsecure permission is granted between
2224 		   the two SIDs, i.e. ahp returns 0. */
2225 		atsecure = avc_has_perm(osid, sid,
2226 					SECCLASS_PROCESS,
2227 					PROCESS__NOATSECURE, NULL);
2228 	}
2229 
2230 	return (atsecure || cap_bprm_secureexec(bprm));
2231 }
2232 
2233 extern struct vfsmount *selinuxfs_mount;
2234 extern struct dentry *selinux_null;
2235 
2236 /* Derived from fs/exec.c:flush_old_files. */
2237 static inline void flush_unauthorized_files(const struct cred *cred,
2238 					    struct files_struct *files)
2239 {
2240 	struct common_audit_data ad;
2241 	struct file *file, *devnull = NULL;
2242 	struct tty_struct *tty;
2243 	struct fdtable *fdt;
2244 	long j = -1;
2245 	int drop_tty = 0;
2246 
2247 	tty = get_current_tty();
2248 	if (tty) {
2249 		file_list_lock();
2250 		if (!list_empty(&tty->tty_files)) {
2251 			struct inode *inode;
2252 
2253 			/* Revalidate access to controlling tty.
2254 			   Use inode_has_perm on the tty inode directly rather
2255 			   than using file_has_perm, as this particular open
2256 			   file may belong to another process and we are only
2257 			   interested in the inode-based check here. */
2258 			file = list_first_entry(&tty->tty_files, struct file, f_u.fu_list);
2259 			inode = file->f_path.dentry->d_inode;
2260 			if (inode_has_perm(cred, inode,
2261 					   FILE__READ | FILE__WRITE, NULL)) {
2262 				drop_tty = 1;
2263 			}
2264 		}
2265 		file_list_unlock();
2266 		tty_kref_put(tty);
2267 	}
2268 	/* Reset controlling tty. */
2269 	if (drop_tty)
2270 		no_tty();
2271 
2272 	/* Revalidate access to inherited open files. */
2273 
2274 	COMMON_AUDIT_DATA_INIT(&ad, FS);
2275 
2276 	spin_lock(&files->file_lock);
2277 	for (;;) {
2278 		unsigned long set, i;
2279 		int fd;
2280 
2281 		j++;
2282 		i = j * __NFDBITS;
2283 		fdt = files_fdtable(files);
2284 		if (i >= fdt->max_fds)
2285 			break;
2286 		set = fdt->open_fds->fds_bits[j];
2287 		if (!set)
2288 			continue;
2289 		spin_unlock(&files->file_lock);
2290 		for ( ; set ; i++, set >>= 1) {
2291 			if (set & 1) {
2292 				file = fget(i);
2293 				if (!file)
2294 					continue;
2295 				if (file_has_perm(cred,
2296 						  file,
2297 						  file_to_av(file))) {
2298 					sys_close(i);
2299 					fd = get_unused_fd();
2300 					if (fd != i) {
2301 						if (fd >= 0)
2302 							put_unused_fd(fd);
2303 						fput(file);
2304 						continue;
2305 					}
2306 					if (devnull) {
2307 						get_file(devnull);
2308 					} else {
2309 						devnull = dentry_open(
2310 							dget(selinux_null),
2311 							mntget(selinuxfs_mount),
2312 							O_RDWR, cred);
2313 						if (IS_ERR(devnull)) {
2314 							devnull = NULL;
2315 							put_unused_fd(fd);
2316 							fput(file);
2317 							continue;
2318 						}
2319 					}
2320 					fd_install(fd, devnull);
2321 				}
2322 				fput(file);
2323 			}
2324 		}
2325 		spin_lock(&files->file_lock);
2326 
2327 	}
2328 	spin_unlock(&files->file_lock);
2329 }
2330 
2331 /*
2332  * Prepare a process for imminent new credential changes due to exec
2333  */
2334 static void selinux_bprm_committing_creds(struct linux_binprm *bprm)
2335 {
2336 	struct task_security_struct *new_tsec;
2337 	struct rlimit *rlim, *initrlim;
2338 	int rc, i;
2339 
2340 	new_tsec = bprm->cred->security;
2341 	if (new_tsec->sid == new_tsec->osid)
2342 		return;
2343 
2344 	/* Close files for which the new task SID is not authorized. */
2345 	flush_unauthorized_files(bprm->cred, current->files);
2346 
2347 	/* Always clear parent death signal on SID transitions. */
2348 	current->pdeath_signal = 0;
2349 
2350 	/* Check whether the new SID can inherit resource limits from the old
2351 	 * SID.  If not, reset all soft limits to the lower of the current
2352 	 * task's hard limit and the init task's soft limit.
2353 	 *
2354 	 * Note that the setting of hard limits (even to lower them) can be
2355 	 * controlled by the setrlimit check.  The inclusion of the init task's
2356 	 * soft limit into the computation is to avoid resetting soft limits
2357 	 * higher than the default soft limit for cases where the default is
2358 	 * lower than the hard limit, e.g. RLIMIT_CORE or RLIMIT_STACK.
2359 	 */
2360 	rc = avc_has_perm(new_tsec->osid, new_tsec->sid, SECCLASS_PROCESS,
2361 			  PROCESS__RLIMITINH, NULL);
2362 	if (rc) {
2363 		for (i = 0; i < RLIM_NLIMITS; i++) {
2364 			rlim = current->signal->rlim + i;
2365 			initrlim = init_task.signal->rlim + i;
2366 			rlim->rlim_cur = min(rlim->rlim_max, initrlim->rlim_cur);
2367 		}
2368 		update_rlimit_cpu(current->signal->rlim[RLIMIT_CPU].rlim_cur);
2369 	}
2370 }
2371 
2372 /*
2373  * Clean up the process immediately after the installation of new credentials
2374  * due to exec
2375  */
2376 static void selinux_bprm_committed_creds(struct linux_binprm *bprm)
2377 {
2378 	const struct task_security_struct *tsec = current_security();
2379 	struct itimerval itimer;
2380 	u32 osid, sid;
2381 	int rc, i;
2382 
2383 	osid = tsec->osid;
2384 	sid = tsec->sid;
2385 
2386 	if (sid == osid)
2387 		return;
2388 
2389 	/* Check whether the new SID can inherit signal state from the old SID.
2390 	 * If not, clear itimers to avoid subsequent signal generation and
2391 	 * flush and unblock signals.
2392 	 *
2393 	 * This must occur _after_ the task SID has been updated so that any
2394 	 * kill done after the flush will be checked against the new SID.
2395 	 */
2396 	rc = avc_has_perm(osid, sid, SECCLASS_PROCESS, PROCESS__SIGINH, NULL);
2397 	if (rc) {
2398 		memset(&itimer, 0, sizeof itimer);
2399 		for (i = 0; i < 3; i++)
2400 			do_setitimer(i, &itimer, NULL);
2401 		spin_lock_irq(&current->sighand->siglock);
2402 		if (!(current->signal->flags & SIGNAL_GROUP_EXIT)) {
2403 			__flush_signals(current);
2404 			flush_signal_handlers(current, 1);
2405 			sigemptyset(&current->blocked);
2406 		}
2407 		spin_unlock_irq(&current->sighand->siglock);
2408 	}
2409 
2410 	/* Wake up the parent if it is waiting so that it can recheck
2411 	 * wait permission to the new task SID. */
2412 	read_lock(&tasklist_lock);
2413 	__wake_up_parent(current, current->real_parent);
2414 	read_unlock(&tasklist_lock);
2415 }
2416 
2417 /* superblock security operations */
2418 
2419 static int selinux_sb_alloc_security(struct super_block *sb)
2420 {
2421 	return superblock_alloc_security(sb);
2422 }
2423 
2424 static void selinux_sb_free_security(struct super_block *sb)
2425 {
2426 	superblock_free_security(sb);
2427 }
2428 
2429 static inline int match_prefix(char *prefix, int plen, char *option, int olen)
2430 {
2431 	if (plen > olen)
2432 		return 0;
2433 
2434 	return !memcmp(prefix, option, plen);
2435 }
2436 
2437 static inline int selinux_option(char *option, int len)
2438 {
2439 	return (match_prefix(CONTEXT_STR, sizeof(CONTEXT_STR)-1, option, len) ||
2440 		match_prefix(FSCONTEXT_STR, sizeof(FSCONTEXT_STR)-1, option, len) ||
2441 		match_prefix(DEFCONTEXT_STR, sizeof(DEFCONTEXT_STR)-1, option, len) ||
2442 		match_prefix(ROOTCONTEXT_STR, sizeof(ROOTCONTEXT_STR)-1, option, len) ||
2443 		match_prefix(LABELSUPP_STR, sizeof(LABELSUPP_STR)-1, option, len));
2444 }
2445 
2446 static inline void take_option(char **to, char *from, int *first, int len)
2447 {
2448 	if (!*first) {
2449 		**to = ',';
2450 		*to += 1;
2451 	} else
2452 		*first = 0;
2453 	memcpy(*to, from, len);
2454 	*to += len;
2455 }
2456 
2457 static inline void take_selinux_option(char **to, char *from, int *first,
2458 				       int len)
2459 {
2460 	int current_size = 0;
2461 
2462 	if (!*first) {
2463 		**to = '|';
2464 		*to += 1;
2465 	} else
2466 		*first = 0;
2467 
2468 	while (current_size < len) {
2469 		if (*from != '"') {
2470 			**to = *from;
2471 			*to += 1;
2472 		}
2473 		from += 1;
2474 		current_size += 1;
2475 	}
2476 }
2477 
2478 static int selinux_sb_copy_data(char *orig, char *copy)
2479 {
2480 	int fnosec, fsec, rc = 0;
2481 	char *in_save, *in_curr, *in_end;
2482 	char *sec_curr, *nosec_save, *nosec;
2483 	int open_quote = 0;
2484 
2485 	in_curr = orig;
2486 	sec_curr = copy;
2487 
2488 	nosec = (char *)get_zeroed_page(GFP_KERNEL);
2489 	if (!nosec) {
2490 		rc = -ENOMEM;
2491 		goto out;
2492 	}
2493 
2494 	nosec_save = nosec;
2495 	fnosec = fsec = 1;
2496 	in_save = in_end = orig;
2497 
2498 	do {
2499 		if (*in_end == '"')
2500 			open_quote = !open_quote;
2501 		if ((*in_end == ',' && open_quote == 0) ||
2502 				*in_end == '\0') {
2503 			int len = in_end - in_curr;
2504 
2505 			if (selinux_option(in_curr, len))
2506 				take_selinux_option(&sec_curr, in_curr, &fsec, len);
2507 			else
2508 				take_option(&nosec, in_curr, &fnosec, len);
2509 
2510 			in_curr = in_end + 1;
2511 		}
2512 	} while (*in_end++);
2513 
2514 	strcpy(in_save, nosec_save);
2515 	free_page((unsigned long)nosec_save);
2516 out:
2517 	return rc;
2518 }
2519 
2520 static int selinux_sb_kern_mount(struct super_block *sb, int flags, void *data)
2521 {
2522 	const struct cred *cred = current_cred();
2523 	struct common_audit_data ad;
2524 	int rc;
2525 
2526 	rc = superblock_doinit(sb, data);
2527 	if (rc)
2528 		return rc;
2529 
2530 	/* Allow all mounts performed by the kernel */
2531 	if (flags & MS_KERNMOUNT)
2532 		return 0;
2533 
2534 	COMMON_AUDIT_DATA_INIT(&ad, FS);
2535 	ad.u.fs.path.dentry = sb->s_root;
2536 	return superblock_has_perm(cred, sb, FILESYSTEM__MOUNT, &ad);
2537 }
2538 
2539 static int selinux_sb_statfs(struct dentry *dentry)
2540 {
2541 	const struct cred *cred = current_cred();
2542 	struct common_audit_data ad;
2543 
2544 	COMMON_AUDIT_DATA_INIT(&ad, FS);
2545 	ad.u.fs.path.dentry = dentry->d_sb->s_root;
2546 	return superblock_has_perm(cred, dentry->d_sb, FILESYSTEM__GETATTR, &ad);
2547 }
2548 
2549 static int selinux_mount(char *dev_name,
2550 			 struct path *path,
2551 			 char *type,
2552 			 unsigned long flags,
2553 			 void *data)
2554 {
2555 	const struct cred *cred = current_cred();
2556 
2557 	if (flags & MS_REMOUNT)
2558 		return superblock_has_perm(cred, path->mnt->mnt_sb,
2559 					   FILESYSTEM__REMOUNT, NULL);
2560 	else
2561 		return dentry_has_perm(cred, path->mnt, path->dentry,
2562 				       FILE__MOUNTON);
2563 }
2564 
2565 static int selinux_umount(struct vfsmount *mnt, int flags)
2566 {
2567 	const struct cred *cred = current_cred();
2568 
2569 	return superblock_has_perm(cred, mnt->mnt_sb,
2570 				   FILESYSTEM__UNMOUNT, NULL);
2571 }
2572 
2573 /* inode security operations */
2574 
2575 static int selinux_inode_alloc_security(struct inode *inode)
2576 {
2577 	return inode_alloc_security(inode);
2578 }
2579 
2580 static void selinux_inode_free_security(struct inode *inode)
2581 {
2582 	inode_free_security(inode);
2583 }
2584 
2585 static int selinux_inode_init_security(struct inode *inode, struct inode *dir,
2586 				       char **name, void **value,
2587 				       size_t *len)
2588 {
2589 	const struct cred *cred = current_cred();
2590 	const struct task_security_struct *tsec = cred->security;
2591 	struct inode_security_struct *dsec;
2592 	struct superblock_security_struct *sbsec;
2593 	u32 sid, newsid, clen;
2594 	int rc;
2595 	char *namep = NULL, *context;
2596 
2597 	dsec = dir->i_security;
2598 	sbsec = dir->i_sb->s_security;
2599 
2600 	sid = tsec->sid;
2601 	newsid = tsec->create_sid;
2602 
2603 	if (!newsid || !(sbsec->flags & SE_SBLABELSUPP)) {
2604 		rc = security_transition_sid(sid, dsec->sid,
2605 					     inode_mode_to_security_class(inode->i_mode),
2606 					     &newsid);
2607 		if (rc) {
2608 			printk(KERN_WARNING "%s:  "
2609 			       "security_transition_sid failed, rc=%d (dev=%s "
2610 			       "ino=%ld)\n",
2611 			       __func__,
2612 			       -rc, inode->i_sb->s_id, inode->i_ino);
2613 			return rc;
2614 		}
2615 	}
2616 
2617 	/* Possibly defer initialization to selinux_complete_init. */
2618 	if (sbsec->flags & SE_SBINITIALIZED) {
2619 		struct inode_security_struct *isec = inode->i_security;
2620 		isec->sclass = inode_mode_to_security_class(inode->i_mode);
2621 		isec->sid = newsid;
2622 		isec->initialized = 1;
2623 	}
2624 
2625 	if (!ss_initialized || !(sbsec->flags & SE_SBLABELSUPP))
2626 		return -EOPNOTSUPP;
2627 
2628 	if (name) {
2629 		namep = kstrdup(XATTR_SELINUX_SUFFIX, GFP_NOFS);
2630 		if (!namep)
2631 			return -ENOMEM;
2632 		*name = namep;
2633 	}
2634 
2635 	if (value && len) {
2636 		rc = security_sid_to_context_force(newsid, &context, &clen);
2637 		if (rc) {
2638 			kfree(namep);
2639 			return rc;
2640 		}
2641 		*value = context;
2642 		*len = clen;
2643 	}
2644 
2645 	return 0;
2646 }
2647 
2648 static int selinux_inode_create(struct inode *dir, struct dentry *dentry, int mask)
2649 {
2650 	return may_create(dir, dentry, SECCLASS_FILE);
2651 }
2652 
2653 static int selinux_inode_link(struct dentry *old_dentry, struct inode *dir, struct dentry *new_dentry)
2654 {
2655 	return may_link(dir, old_dentry, MAY_LINK);
2656 }
2657 
2658 static int selinux_inode_unlink(struct inode *dir, struct dentry *dentry)
2659 {
2660 	return may_link(dir, dentry, MAY_UNLINK);
2661 }
2662 
2663 static int selinux_inode_symlink(struct inode *dir, struct dentry *dentry, const char *name)
2664 {
2665 	return may_create(dir, dentry, SECCLASS_LNK_FILE);
2666 }
2667 
2668 static int selinux_inode_mkdir(struct inode *dir, struct dentry *dentry, int mask)
2669 {
2670 	return may_create(dir, dentry, SECCLASS_DIR);
2671 }
2672 
2673 static int selinux_inode_rmdir(struct inode *dir, struct dentry *dentry)
2674 {
2675 	return may_link(dir, dentry, MAY_RMDIR);
2676 }
2677 
2678 static int selinux_inode_mknod(struct inode *dir, struct dentry *dentry, int mode, dev_t dev)
2679 {
2680 	return may_create(dir, dentry, inode_mode_to_security_class(mode));
2681 }
2682 
2683 static int selinux_inode_rename(struct inode *old_inode, struct dentry *old_dentry,
2684 				struct inode *new_inode, struct dentry *new_dentry)
2685 {
2686 	return may_rename(old_inode, old_dentry, new_inode, new_dentry);
2687 }
2688 
2689 static int selinux_inode_readlink(struct dentry *dentry)
2690 {
2691 	const struct cred *cred = current_cred();
2692 
2693 	return dentry_has_perm(cred, NULL, dentry, FILE__READ);
2694 }
2695 
2696 static int selinux_inode_follow_link(struct dentry *dentry, struct nameidata *nameidata)
2697 {
2698 	const struct cred *cred = current_cred();
2699 
2700 	return dentry_has_perm(cred, NULL, dentry, FILE__READ);
2701 }
2702 
2703 static int selinux_inode_permission(struct inode *inode, int mask)
2704 {
2705 	const struct cred *cred = current_cred();
2706 
2707 	if (!mask) {
2708 		/* No permission to check.  Existence test. */
2709 		return 0;
2710 	}
2711 
2712 	return inode_has_perm(cred, inode,
2713 			      file_mask_to_av(inode->i_mode, mask), NULL);
2714 }
2715 
2716 static int selinux_inode_setattr(struct dentry *dentry, struct iattr *iattr)
2717 {
2718 	const struct cred *cred = current_cred();
2719 	unsigned int ia_valid = iattr->ia_valid;
2720 
2721 	/* ATTR_FORCE is just used for ATTR_KILL_S[UG]ID. */
2722 	if (ia_valid & ATTR_FORCE) {
2723 		ia_valid &= ~(ATTR_KILL_SUID | ATTR_KILL_SGID | ATTR_MODE |
2724 			      ATTR_FORCE);
2725 		if (!ia_valid)
2726 			return 0;
2727 	}
2728 
2729 	if (ia_valid & (ATTR_MODE | ATTR_UID | ATTR_GID |
2730 			ATTR_ATIME_SET | ATTR_MTIME_SET | ATTR_TIMES_SET))
2731 		return dentry_has_perm(cred, NULL, dentry, FILE__SETATTR);
2732 
2733 	return dentry_has_perm(cred, NULL, dentry, FILE__WRITE);
2734 }
2735 
2736 static int selinux_inode_getattr(struct vfsmount *mnt, struct dentry *dentry)
2737 {
2738 	const struct cred *cred = current_cred();
2739 
2740 	return dentry_has_perm(cred, mnt, dentry, FILE__GETATTR);
2741 }
2742 
2743 static int selinux_inode_setotherxattr(struct dentry *dentry, const char *name)
2744 {
2745 	const struct cred *cred = current_cred();
2746 
2747 	if (!strncmp(name, XATTR_SECURITY_PREFIX,
2748 		     sizeof XATTR_SECURITY_PREFIX - 1)) {
2749 		if (!strcmp(name, XATTR_NAME_CAPS)) {
2750 			if (!capable(CAP_SETFCAP))
2751 				return -EPERM;
2752 		} else if (!capable(CAP_SYS_ADMIN)) {
2753 			/* A different attribute in the security namespace.
2754 			   Restrict to administrator. */
2755 			return -EPERM;
2756 		}
2757 	}
2758 
2759 	/* Not an attribute we recognize, so just check the
2760 	   ordinary setattr permission. */
2761 	return dentry_has_perm(cred, NULL, dentry, FILE__SETATTR);
2762 }
2763 
2764 static int selinux_inode_setxattr(struct dentry *dentry, const char *name,
2765 				  const void *value, size_t size, int flags)
2766 {
2767 	struct inode *inode = dentry->d_inode;
2768 	struct inode_security_struct *isec = inode->i_security;
2769 	struct superblock_security_struct *sbsec;
2770 	struct common_audit_data ad;
2771 	u32 newsid, sid = current_sid();
2772 	int rc = 0;
2773 
2774 	if (strcmp(name, XATTR_NAME_SELINUX))
2775 		return selinux_inode_setotherxattr(dentry, name);
2776 
2777 	sbsec = inode->i_sb->s_security;
2778 	if (!(sbsec->flags & SE_SBLABELSUPP))
2779 		return -EOPNOTSUPP;
2780 
2781 	if (!is_owner_or_cap(inode))
2782 		return -EPERM;
2783 
2784 	COMMON_AUDIT_DATA_INIT(&ad, FS);
2785 	ad.u.fs.path.dentry = dentry;
2786 
2787 	rc = avc_has_perm(sid, isec->sid, isec->sclass,
2788 			  FILE__RELABELFROM, &ad);
2789 	if (rc)
2790 		return rc;
2791 
2792 	rc = security_context_to_sid(value, size, &newsid);
2793 	if (rc == -EINVAL) {
2794 		if (!capable(CAP_MAC_ADMIN))
2795 			return rc;
2796 		rc = security_context_to_sid_force(value, size, &newsid);
2797 	}
2798 	if (rc)
2799 		return rc;
2800 
2801 	rc = avc_has_perm(sid, newsid, isec->sclass,
2802 			  FILE__RELABELTO, &ad);
2803 	if (rc)
2804 		return rc;
2805 
2806 	rc = security_validate_transition(isec->sid, newsid, sid,
2807 					  isec->sclass);
2808 	if (rc)
2809 		return rc;
2810 
2811 	return avc_has_perm(newsid,
2812 			    sbsec->sid,
2813 			    SECCLASS_FILESYSTEM,
2814 			    FILESYSTEM__ASSOCIATE,
2815 			    &ad);
2816 }
2817 
2818 static void selinux_inode_post_setxattr(struct dentry *dentry, const char *name,
2819 					const void *value, size_t size,
2820 					int flags)
2821 {
2822 	struct inode *inode = dentry->d_inode;
2823 	struct inode_security_struct *isec = inode->i_security;
2824 	u32 newsid;
2825 	int rc;
2826 
2827 	if (strcmp(name, XATTR_NAME_SELINUX)) {
2828 		/* Not an attribute we recognize, so nothing to do. */
2829 		return;
2830 	}
2831 
2832 	rc = security_context_to_sid_force(value, size, &newsid);
2833 	if (rc) {
2834 		printk(KERN_ERR "SELinux:  unable to map context to SID"
2835 		       "for (%s, %lu), rc=%d\n",
2836 		       inode->i_sb->s_id, inode->i_ino, -rc);
2837 		return;
2838 	}
2839 
2840 	isec->sid = newsid;
2841 	return;
2842 }
2843 
2844 static int selinux_inode_getxattr(struct dentry *dentry, const char *name)
2845 {
2846 	const struct cred *cred = current_cred();
2847 
2848 	return dentry_has_perm(cred, NULL, dentry, FILE__GETATTR);
2849 }
2850 
2851 static int selinux_inode_listxattr(struct dentry *dentry)
2852 {
2853 	const struct cred *cred = current_cred();
2854 
2855 	return dentry_has_perm(cred, NULL, dentry, FILE__GETATTR);
2856 }
2857 
2858 static int selinux_inode_removexattr(struct dentry *dentry, const char *name)
2859 {
2860 	if (strcmp(name, XATTR_NAME_SELINUX))
2861 		return selinux_inode_setotherxattr(dentry, name);
2862 
2863 	/* No one is allowed to remove a SELinux security label.
2864 	   You can change the label, but all data must be labeled. */
2865 	return -EACCES;
2866 }
2867 
2868 /*
2869  * Copy the inode security context value to the user.
2870  *
2871  * Permission check is handled by selinux_inode_getxattr hook.
2872  */
2873 static int selinux_inode_getsecurity(const struct inode *inode, const char *name, void **buffer, bool alloc)
2874 {
2875 	u32 size;
2876 	int error;
2877 	char *context = NULL;
2878 	struct inode_security_struct *isec = inode->i_security;
2879 
2880 	if (strcmp(name, XATTR_SELINUX_SUFFIX))
2881 		return -EOPNOTSUPP;
2882 
2883 	/*
2884 	 * If the caller has CAP_MAC_ADMIN, then get the raw context
2885 	 * value even if it is not defined by current policy; otherwise,
2886 	 * use the in-core value under current policy.
2887 	 * Use the non-auditing forms of the permission checks since
2888 	 * getxattr may be called by unprivileged processes commonly
2889 	 * and lack of permission just means that we fall back to the
2890 	 * in-core context value, not a denial.
2891 	 */
2892 	error = selinux_capable(current, current_cred(), CAP_MAC_ADMIN,
2893 				SECURITY_CAP_NOAUDIT);
2894 	if (!error)
2895 		error = security_sid_to_context_force(isec->sid, &context,
2896 						      &size);
2897 	else
2898 		error = security_sid_to_context(isec->sid, &context, &size);
2899 	if (error)
2900 		return error;
2901 	error = size;
2902 	if (alloc) {
2903 		*buffer = context;
2904 		goto out_nofree;
2905 	}
2906 	kfree(context);
2907 out_nofree:
2908 	return error;
2909 }
2910 
2911 static int selinux_inode_setsecurity(struct inode *inode, const char *name,
2912 				     const void *value, size_t size, int flags)
2913 {
2914 	struct inode_security_struct *isec = inode->i_security;
2915 	u32 newsid;
2916 	int rc;
2917 
2918 	if (strcmp(name, XATTR_SELINUX_SUFFIX))
2919 		return -EOPNOTSUPP;
2920 
2921 	if (!value || !size)
2922 		return -EACCES;
2923 
2924 	rc = security_context_to_sid((void *)value, size, &newsid);
2925 	if (rc)
2926 		return rc;
2927 
2928 	isec->sid = newsid;
2929 	isec->initialized = 1;
2930 	return 0;
2931 }
2932 
2933 static int selinux_inode_listsecurity(struct inode *inode, char *buffer, size_t buffer_size)
2934 {
2935 	const int len = sizeof(XATTR_NAME_SELINUX);
2936 	if (buffer && len <= buffer_size)
2937 		memcpy(buffer, XATTR_NAME_SELINUX, len);
2938 	return len;
2939 }
2940 
2941 static void selinux_inode_getsecid(const struct inode *inode, u32 *secid)
2942 {
2943 	struct inode_security_struct *isec = inode->i_security;
2944 	*secid = isec->sid;
2945 }
2946 
2947 /* file security operations */
2948 
2949 static int selinux_revalidate_file_permission(struct file *file, int mask)
2950 {
2951 	const struct cred *cred = current_cred();
2952 	struct inode *inode = file->f_path.dentry->d_inode;
2953 
2954 	/* file_mask_to_av won't add FILE__WRITE if MAY_APPEND is set */
2955 	if ((file->f_flags & O_APPEND) && (mask & MAY_WRITE))
2956 		mask |= MAY_APPEND;
2957 
2958 	return file_has_perm(cred, file,
2959 			     file_mask_to_av(inode->i_mode, mask));
2960 }
2961 
2962 static int selinux_file_permission(struct file *file, int mask)
2963 {
2964 	struct inode *inode = file->f_path.dentry->d_inode;
2965 	struct file_security_struct *fsec = file->f_security;
2966 	struct inode_security_struct *isec = inode->i_security;
2967 	u32 sid = current_sid();
2968 
2969 	if (!mask)
2970 		/* No permission to check.  Existence test. */
2971 		return 0;
2972 
2973 	if (sid == fsec->sid && fsec->isid == isec->sid &&
2974 	    fsec->pseqno == avc_policy_seqno())
2975 		/* No change since dentry_open check. */
2976 		return 0;
2977 
2978 	return selinux_revalidate_file_permission(file, mask);
2979 }
2980 
2981 static int selinux_file_alloc_security(struct file *file)
2982 {
2983 	return file_alloc_security(file);
2984 }
2985 
2986 static void selinux_file_free_security(struct file *file)
2987 {
2988 	file_free_security(file);
2989 }
2990 
2991 static int selinux_file_ioctl(struct file *file, unsigned int cmd,
2992 			      unsigned long arg)
2993 {
2994 	const struct cred *cred = current_cred();
2995 	u32 av = 0;
2996 
2997 	if (_IOC_DIR(cmd) & _IOC_WRITE)
2998 		av |= FILE__WRITE;
2999 	if (_IOC_DIR(cmd) & _IOC_READ)
3000 		av |= FILE__READ;
3001 	if (!av)
3002 		av = FILE__IOCTL;
3003 
3004 	return file_has_perm(cred, file, av);
3005 }
3006 
3007 static int file_map_prot_check(struct file *file, unsigned long prot, int shared)
3008 {
3009 	const struct cred *cred = current_cred();
3010 	int rc = 0;
3011 
3012 #ifndef CONFIG_PPC32
3013 	if ((prot & PROT_EXEC) && (!file || (!shared && (prot & PROT_WRITE)))) {
3014 		/*
3015 		 * We are making executable an anonymous mapping or a
3016 		 * private file mapping that will also be writable.
3017 		 * This has an additional check.
3018 		 */
3019 		rc = cred_has_perm(cred, cred, PROCESS__EXECMEM);
3020 		if (rc)
3021 			goto error;
3022 	}
3023 #endif
3024 
3025 	if (file) {
3026 		/* read access is always possible with a mapping */
3027 		u32 av = FILE__READ;
3028 
3029 		/* write access only matters if the mapping is shared */
3030 		if (shared && (prot & PROT_WRITE))
3031 			av |= FILE__WRITE;
3032 
3033 		if (prot & PROT_EXEC)
3034 			av |= FILE__EXECUTE;
3035 
3036 		return file_has_perm(cred, file, av);
3037 	}
3038 
3039 error:
3040 	return rc;
3041 }
3042 
3043 static int selinux_file_mmap(struct file *file, unsigned long reqprot,
3044 			     unsigned long prot, unsigned long flags,
3045 			     unsigned long addr, unsigned long addr_only)
3046 {
3047 	int rc = 0;
3048 	u32 sid = current_sid();
3049 
3050 	/*
3051 	 * notice that we are intentionally putting the SELinux check before
3052 	 * the secondary cap_file_mmap check.  This is such a likely attempt
3053 	 * at bad behaviour/exploit that we always want to get the AVC, even
3054 	 * if DAC would have also denied the operation.
3055 	 */
3056 	if (addr < CONFIG_LSM_MMAP_MIN_ADDR) {
3057 		rc = avc_has_perm(sid, sid, SECCLASS_MEMPROTECT,
3058 				  MEMPROTECT__MMAP_ZERO, NULL);
3059 		if (rc)
3060 			return rc;
3061 	}
3062 
3063 	/* do DAC check on address space usage */
3064 	rc = cap_file_mmap(file, reqprot, prot, flags, addr, addr_only);
3065 	if (rc || addr_only)
3066 		return rc;
3067 
3068 	if (selinux_checkreqprot)
3069 		prot = reqprot;
3070 
3071 	return file_map_prot_check(file, prot,
3072 				   (flags & MAP_TYPE) == MAP_SHARED);
3073 }
3074 
3075 static int selinux_file_mprotect(struct vm_area_struct *vma,
3076 				 unsigned long reqprot,
3077 				 unsigned long prot)
3078 {
3079 	const struct cred *cred = current_cred();
3080 
3081 	if (selinux_checkreqprot)
3082 		prot = reqprot;
3083 
3084 #ifndef CONFIG_PPC32
3085 	if ((prot & PROT_EXEC) && !(vma->vm_flags & VM_EXEC)) {
3086 		int rc = 0;
3087 		if (vma->vm_start >= vma->vm_mm->start_brk &&
3088 		    vma->vm_end <= vma->vm_mm->brk) {
3089 			rc = cred_has_perm(cred, cred, PROCESS__EXECHEAP);
3090 		} else if (!vma->vm_file &&
3091 			   vma->vm_start <= vma->vm_mm->start_stack &&
3092 			   vma->vm_end >= vma->vm_mm->start_stack) {
3093 			rc = current_has_perm(current, PROCESS__EXECSTACK);
3094 		} else if (vma->vm_file && vma->anon_vma) {
3095 			/*
3096 			 * We are making executable a file mapping that has
3097 			 * had some COW done. Since pages might have been
3098 			 * written, check ability to execute the possibly
3099 			 * modified content.  This typically should only
3100 			 * occur for text relocations.
3101 			 */
3102 			rc = file_has_perm(cred, vma->vm_file, FILE__EXECMOD);
3103 		}
3104 		if (rc)
3105 			return rc;
3106 	}
3107 #endif
3108 
3109 	return file_map_prot_check(vma->vm_file, prot, vma->vm_flags&VM_SHARED);
3110 }
3111 
3112 static int selinux_file_lock(struct file *file, unsigned int cmd)
3113 {
3114 	const struct cred *cred = current_cred();
3115 
3116 	return file_has_perm(cred, file, FILE__LOCK);
3117 }
3118 
3119 static int selinux_file_fcntl(struct file *file, unsigned int cmd,
3120 			      unsigned long arg)
3121 {
3122 	const struct cred *cred = current_cred();
3123 	int err = 0;
3124 
3125 	switch (cmd) {
3126 	case F_SETFL:
3127 		if (!file->f_path.dentry || !file->f_path.dentry->d_inode) {
3128 			err = -EINVAL;
3129 			break;
3130 		}
3131 
3132 		if ((file->f_flags & O_APPEND) && !(arg & O_APPEND)) {
3133 			err = file_has_perm(cred, file, FILE__WRITE);
3134 			break;
3135 		}
3136 		/* fall through */
3137 	case F_SETOWN:
3138 	case F_SETSIG:
3139 	case F_GETFL:
3140 	case F_GETOWN:
3141 	case F_GETSIG:
3142 		/* Just check FD__USE permission */
3143 		err = file_has_perm(cred, file, 0);
3144 		break;
3145 	case F_GETLK:
3146 	case F_SETLK:
3147 	case F_SETLKW:
3148 #if BITS_PER_LONG == 32
3149 	case F_GETLK64:
3150 	case F_SETLK64:
3151 	case F_SETLKW64:
3152 #endif
3153 		if (!file->f_path.dentry || !file->f_path.dentry->d_inode) {
3154 			err = -EINVAL;
3155 			break;
3156 		}
3157 		err = file_has_perm(cred, file, FILE__LOCK);
3158 		break;
3159 	}
3160 
3161 	return err;
3162 }
3163 
3164 static int selinux_file_set_fowner(struct file *file)
3165 {
3166 	struct file_security_struct *fsec;
3167 
3168 	fsec = file->f_security;
3169 	fsec->fown_sid = current_sid();
3170 
3171 	return 0;
3172 }
3173 
3174 static int selinux_file_send_sigiotask(struct task_struct *tsk,
3175 				       struct fown_struct *fown, int signum)
3176 {
3177 	struct file *file;
3178 	u32 sid = task_sid(tsk);
3179 	u32 perm;
3180 	struct file_security_struct *fsec;
3181 
3182 	/* struct fown_struct is never outside the context of a struct file */
3183 	file = container_of(fown, struct file, f_owner);
3184 
3185 	fsec = file->f_security;
3186 
3187 	if (!signum)
3188 		perm = signal_to_av(SIGIO); /* as per send_sigio_to_task */
3189 	else
3190 		perm = signal_to_av(signum);
3191 
3192 	return avc_has_perm(fsec->fown_sid, sid,
3193 			    SECCLASS_PROCESS, perm, NULL);
3194 }
3195 
3196 static int selinux_file_receive(struct file *file)
3197 {
3198 	const struct cred *cred = current_cred();
3199 
3200 	return file_has_perm(cred, file, file_to_av(file));
3201 }
3202 
3203 static int selinux_dentry_open(struct file *file, const struct cred *cred)
3204 {
3205 	struct file_security_struct *fsec;
3206 	struct inode *inode;
3207 	struct inode_security_struct *isec;
3208 
3209 	inode = file->f_path.dentry->d_inode;
3210 	fsec = file->f_security;
3211 	isec = inode->i_security;
3212 	/*
3213 	 * Save inode label and policy sequence number
3214 	 * at open-time so that selinux_file_permission
3215 	 * can determine whether revalidation is necessary.
3216 	 * Task label is already saved in the file security
3217 	 * struct as its SID.
3218 	 */
3219 	fsec->isid = isec->sid;
3220 	fsec->pseqno = avc_policy_seqno();
3221 	/*
3222 	 * Since the inode label or policy seqno may have changed
3223 	 * between the selinux_inode_permission check and the saving
3224 	 * of state above, recheck that access is still permitted.
3225 	 * Otherwise, access might never be revalidated against the
3226 	 * new inode label or new policy.
3227 	 * This check is not redundant - do not remove.
3228 	 */
3229 	return inode_has_perm(cred, inode, open_file_to_av(file), NULL);
3230 }
3231 
3232 /* task security operations */
3233 
3234 static int selinux_task_create(unsigned long clone_flags)
3235 {
3236 	return current_has_perm(current, PROCESS__FORK);
3237 }
3238 
3239 /*
3240  * allocate the SELinux part of blank credentials
3241  */
3242 static int selinux_cred_alloc_blank(struct cred *cred, gfp_t gfp)
3243 {
3244 	struct task_security_struct *tsec;
3245 
3246 	tsec = kzalloc(sizeof(struct task_security_struct), gfp);
3247 	if (!tsec)
3248 		return -ENOMEM;
3249 
3250 	cred->security = tsec;
3251 	return 0;
3252 }
3253 
3254 /*
3255  * detach and free the LSM part of a set of credentials
3256  */
3257 static void selinux_cred_free(struct cred *cred)
3258 {
3259 	struct task_security_struct *tsec = cred->security;
3260 
3261 	BUG_ON((unsigned long) cred->security < PAGE_SIZE);
3262 	cred->security = (void *) 0x7UL;
3263 	kfree(tsec);
3264 }
3265 
3266 /*
3267  * prepare a new set of credentials for modification
3268  */
3269 static int selinux_cred_prepare(struct cred *new, const struct cred *old,
3270 				gfp_t gfp)
3271 {
3272 	const struct task_security_struct *old_tsec;
3273 	struct task_security_struct *tsec;
3274 
3275 	old_tsec = old->security;
3276 
3277 	tsec = kmemdup(old_tsec, sizeof(struct task_security_struct), gfp);
3278 	if (!tsec)
3279 		return -ENOMEM;
3280 
3281 	new->security = tsec;
3282 	return 0;
3283 }
3284 
3285 /*
3286  * transfer the SELinux data to a blank set of creds
3287  */
3288 static void selinux_cred_transfer(struct cred *new, const struct cred *old)
3289 {
3290 	const struct task_security_struct *old_tsec = old->security;
3291 	struct task_security_struct *tsec = new->security;
3292 
3293 	*tsec = *old_tsec;
3294 }
3295 
3296 /*
3297  * set the security data for a kernel service
3298  * - all the creation contexts are set to unlabelled
3299  */
3300 static int selinux_kernel_act_as(struct cred *new, u32 secid)
3301 {
3302 	struct task_security_struct *tsec = new->security;
3303 	u32 sid = current_sid();
3304 	int ret;
3305 
3306 	ret = avc_has_perm(sid, secid,
3307 			   SECCLASS_KERNEL_SERVICE,
3308 			   KERNEL_SERVICE__USE_AS_OVERRIDE,
3309 			   NULL);
3310 	if (ret == 0) {
3311 		tsec->sid = secid;
3312 		tsec->create_sid = 0;
3313 		tsec->keycreate_sid = 0;
3314 		tsec->sockcreate_sid = 0;
3315 	}
3316 	return ret;
3317 }
3318 
3319 /*
3320  * set the file creation context in a security record to the same as the
3321  * objective context of the specified inode
3322  */
3323 static int selinux_kernel_create_files_as(struct cred *new, struct inode *inode)
3324 {
3325 	struct inode_security_struct *isec = inode->i_security;
3326 	struct task_security_struct *tsec = new->security;
3327 	u32 sid = current_sid();
3328 	int ret;
3329 
3330 	ret = avc_has_perm(sid, isec->sid,
3331 			   SECCLASS_KERNEL_SERVICE,
3332 			   KERNEL_SERVICE__CREATE_FILES_AS,
3333 			   NULL);
3334 
3335 	if (ret == 0)
3336 		tsec->create_sid = isec->sid;
3337 	return 0;
3338 }
3339 
3340 static int selinux_kernel_module_request(char *kmod_name)
3341 {
3342 	u32 sid;
3343 	struct common_audit_data ad;
3344 
3345 	sid = task_sid(current);
3346 
3347 	COMMON_AUDIT_DATA_INIT(&ad, KMOD);
3348 	ad.u.kmod_name = kmod_name;
3349 
3350 	return avc_has_perm(sid, SECINITSID_KERNEL, SECCLASS_SYSTEM,
3351 			    SYSTEM__MODULE_REQUEST, &ad);
3352 }
3353 
3354 static int selinux_task_setpgid(struct task_struct *p, pid_t pgid)
3355 {
3356 	return current_has_perm(p, PROCESS__SETPGID);
3357 }
3358 
3359 static int selinux_task_getpgid(struct task_struct *p)
3360 {
3361 	return current_has_perm(p, PROCESS__GETPGID);
3362 }
3363 
3364 static int selinux_task_getsid(struct task_struct *p)
3365 {
3366 	return current_has_perm(p, PROCESS__GETSESSION);
3367 }
3368 
3369 static void selinux_task_getsecid(struct task_struct *p, u32 *secid)
3370 {
3371 	*secid = task_sid(p);
3372 }
3373 
3374 static int selinux_task_setnice(struct task_struct *p, int nice)
3375 {
3376 	int rc;
3377 
3378 	rc = cap_task_setnice(p, nice);
3379 	if (rc)
3380 		return rc;
3381 
3382 	return current_has_perm(p, PROCESS__SETSCHED);
3383 }
3384 
3385 static int selinux_task_setioprio(struct task_struct *p, int ioprio)
3386 {
3387 	int rc;
3388 
3389 	rc = cap_task_setioprio(p, ioprio);
3390 	if (rc)
3391 		return rc;
3392 
3393 	return current_has_perm(p, PROCESS__SETSCHED);
3394 }
3395 
3396 static int selinux_task_getioprio(struct task_struct *p)
3397 {
3398 	return current_has_perm(p, PROCESS__GETSCHED);
3399 }
3400 
3401 static int selinux_task_setrlimit(unsigned int resource, struct rlimit *new_rlim)
3402 {
3403 	struct rlimit *old_rlim = current->signal->rlim + resource;
3404 
3405 	/* Control the ability to change the hard limit (whether
3406 	   lowering or raising it), so that the hard limit can
3407 	   later be used as a safe reset point for the soft limit
3408 	   upon context transitions.  See selinux_bprm_committing_creds. */
3409 	if (old_rlim->rlim_max != new_rlim->rlim_max)
3410 		return current_has_perm(current, PROCESS__SETRLIMIT);
3411 
3412 	return 0;
3413 }
3414 
3415 static int selinux_task_setscheduler(struct task_struct *p, int policy, struct sched_param *lp)
3416 {
3417 	int rc;
3418 
3419 	rc = cap_task_setscheduler(p, policy, lp);
3420 	if (rc)
3421 		return rc;
3422 
3423 	return current_has_perm(p, PROCESS__SETSCHED);
3424 }
3425 
3426 static int selinux_task_getscheduler(struct task_struct *p)
3427 {
3428 	return current_has_perm(p, PROCESS__GETSCHED);
3429 }
3430 
3431 static int selinux_task_movememory(struct task_struct *p)
3432 {
3433 	return current_has_perm(p, PROCESS__SETSCHED);
3434 }
3435 
3436 static int selinux_task_kill(struct task_struct *p, struct siginfo *info,
3437 				int sig, u32 secid)
3438 {
3439 	u32 perm;
3440 	int rc;
3441 
3442 	if (!sig)
3443 		perm = PROCESS__SIGNULL; /* null signal; existence test */
3444 	else
3445 		perm = signal_to_av(sig);
3446 	if (secid)
3447 		rc = avc_has_perm(secid, task_sid(p),
3448 				  SECCLASS_PROCESS, perm, NULL);
3449 	else
3450 		rc = current_has_perm(p, perm);
3451 	return rc;
3452 }
3453 
3454 static int selinux_task_wait(struct task_struct *p)
3455 {
3456 	return task_has_perm(p, current, PROCESS__SIGCHLD);
3457 }
3458 
3459 static void selinux_task_to_inode(struct task_struct *p,
3460 				  struct inode *inode)
3461 {
3462 	struct inode_security_struct *isec = inode->i_security;
3463 	u32 sid = task_sid(p);
3464 
3465 	isec->sid = sid;
3466 	isec->initialized = 1;
3467 }
3468 
3469 /* Returns error only if unable to parse addresses */
3470 static int selinux_parse_skb_ipv4(struct sk_buff *skb,
3471 			struct common_audit_data *ad, u8 *proto)
3472 {
3473 	int offset, ihlen, ret = -EINVAL;
3474 	struct iphdr _iph, *ih;
3475 
3476 	offset = skb_network_offset(skb);
3477 	ih = skb_header_pointer(skb, offset, sizeof(_iph), &_iph);
3478 	if (ih == NULL)
3479 		goto out;
3480 
3481 	ihlen = ih->ihl * 4;
3482 	if (ihlen < sizeof(_iph))
3483 		goto out;
3484 
3485 	ad->u.net.v4info.saddr = ih->saddr;
3486 	ad->u.net.v4info.daddr = ih->daddr;
3487 	ret = 0;
3488 
3489 	if (proto)
3490 		*proto = ih->protocol;
3491 
3492 	switch (ih->protocol) {
3493 	case IPPROTO_TCP: {
3494 		struct tcphdr _tcph, *th;
3495 
3496 		if (ntohs(ih->frag_off) & IP_OFFSET)
3497 			break;
3498 
3499 		offset += ihlen;
3500 		th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph);
3501 		if (th == NULL)
3502 			break;
3503 
3504 		ad->u.net.sport = th->source;
3505 		ad->u.net.dport = th->dest;
3506 		break;
3507 	}
3508 
3509 	case IPPROTO_UDP: {
3510 		struct udphdr _udph, *uh;
3511 
3512 		if (ntohs(ih->frag_off) & IP_OFFSET)
3513 			break;
3514 
3515 		offset += ihlen;
3516 		uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph);
3517 		if (uh == NULL)
3518 			break;
3519 
3520 		ad->u.net.sport = uh->source;
3521 		ad->u.net.dport = uh->dest;
3522 		break;
3523 	}
3524 
3525 	case IPPROTO_DCCP: {
3526 		struct dccp_hdr _dccph, *dh;
3527 
3528 		if (ntohs(ih->frag_off) & IP_OFFSET)
3529 			break;
3530 
3531 		offset += ihlen;
3532 		dh = skb_header_pointer(skb, offset, sizeof(_dccph), &_dccph);
3533 		if (dh == NULL)
3534 			break;
3535 
3536 		ad->u.net.sport = dh->dccph_sport;
3537 		ad->u.net.dport = dh->dccph_dport;
3538 		break;
3539 	}
3540 
3541 	default:
3542 		break;
3543 	}
3544 out:
3545 	return ret;
3546 }
3547 
3548 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
3549 
3550 /* Returns error only if unable to parse addresses */
3551 static int selinux_parse_skb_ipv6(struct sk_buff *skb,
3552 			struct common_audit_data *ad, u8 *proto)
3553 {
3554 	u8 nexthdr;
3555 	int ret = -EINVAL, offset;
3556 	struct ipv6hdr _ipv6h, *ip6;
3557 
3558 	offset = skb_network_offset(skb);
3559 	ip6 = skb_header_pointer(skb, offset, sizeof(_ipv6h), &_ipv6h);
3560 	if (ip6 == NULL)
3561 		goto out;
3562 
3563 	ipv6_addr_copy(&ad->u.net.v6info.saddr, &ip6->saddr);
3564 	ipv6_addr_copy(&ad->u.net.v6info.daddr, &ip6->daddr);
3565 	ret = 0;
3566 
3567 	nexthdr = ip6->nexthdr;
3568 	offset += sizeof(_ipv6h);
3569 	offset = ipv6_skip_exthdr(skb, offset, &nexthdr);
3570 	if (offset < 0)
3571 		goto out;
3572 
3573 	if (proto)
3574 		*proto = nexthdr;
3575 
3576 	switch (nexthdr) {
3577 	case IPPROTO_TCP: {
3578 		struct tcphdr _tcph, *th;
3579 
3580 		th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph);
3581 		if (th == NULL)
3582 			break;
3583 
3584 		ad->u.net.sport = th->source;
3585 		ad->u.net.dport = th->dest;
3586 		break;
3587 	}
3588 
3589 	case IPPROTO_UDP: {
3590 		struct udphdr _udph, *uh;
3591 
3592 		uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph);
3593 		if (uh == NULL)
3594 			break;
3595 
3596 		ad->u.net.sport = uh->source;
3597 		ad->u.net.dport = uh->dest;
3598 		break;
3599 	}
3600 
3601 	case IPPROTO_DCCP: {
3602 		struct dccp_hdr _dccph, *dh;
3603 
3604 		dh = skb_header_pointer(skb, offset, sizeof(_dccph), &_dccph);
3605 		if (dh == NULL)
3606 			break;
3607 
3608 		ad->u.net.sport = dh->dccph_sport;
3609 		ad->u.net.dport = dh->dccph_dport;
3610 		break;
3611 	}
3612 
3613 	/* includes fragments */
3614 	default:
3615 		break;
3616 	}
3617 out:
3618 	return ret;
3619 }
3620 
3621 #endif /* IPV6 */
3622 
3623 static int selinux_parse_skb(struct sk_buff *skb, struct common_audit_data *ad,
3624 			     char **_addrp, int src, u8 *proto)
3625 {
3626 	char *addrp;
3627 	int ret;
3628 
3629 	switch (ad->u.net.family) {
3630 	case PF_INET:
3631 		ret = selinux_parse_skb_ipv4(skb, ad, proto);
3632 		if (ret)
3633 			goto parse_error;
3634 		addrp = (char *)(src ? &ad->u.net.v4info.saddr :
3635 				       &ad->u.net.v4info.daddr);
3636 		goto okay;
3637 
3638 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
3639 	case PF_INET6:
3640 		ret = selinux_parse_skb_ipv6(skb, ad, proto);
3641 		if (ret)
3642 			goto parse_error;
3643 		addrp = (char *)(src ? &ad->u.net.v6info.saddr :
3644 				       &ad->u.net.v6info.daddr);
3645 		goto okay;
3646 #endif	/* IPV6 */
3647 	default:
3648 		addrp = NULL;
3649 		goto okay;
3650 	}
3651 
3652 parse_error:
3653 	printk(KERN_WARNING
3654 	       "SELinux: failure in selinux_parse_skb(),"
3655 	       " unable to parse packet\n");
3656 	return ret;
3657 
3658 okay:
3659 	if (_addrp)
3660 		*_addrp = addrp;
3661 	return 0;
3662 }
3663 
3664 /**
3665  * selinux_skb_peerlbl_sid - Determine the peer label of a packet
3666  * @skb: the packet
3667  * @family: protocol family
3668  * @sid: the packet's peer label SID
3669  *
3670  * Description:
3671  * Check the various different forms of network peer labeling and determine
3672  * the peer label/SID for the packet; most of the magic actually occurs in
3673  * the security server function security_net_peersid_cmp().  The function
3674  * returns zero if the value in @sid is valid (although it may be SECSID_NULL)
3675  * or -EACCES if @sid is invalid due to inconsistencies with the different
3676  * peer labels.
3677  *
3678  */
3679 static int selinux_skb_peerlbl_sid(struct sk_buff *skb, u16 family, u32 *sid)
3680 {
3681 	int err;
3682 	u32 xfrm_sid;
3683 	u32 nlbl_sid;
3684 	u32 nlbl_type;
3685 
3686 	selinux_skb_xfrm_sid(skb, &xfrm_sid);
3687 	selinux_netlbl_skbuff_getsid(skb, family, &nlbl_type, &nlbl_sid);
3688 
3689 	err = security_net_peersid_resolve(nlbl_sid, nlbl_type, xfrm_sid, sid);
3690 	if (unlikely(err)) {
3691 		printk(KERN_WARNING
3692 		       "SELinux: failure in selinux_skb_peerlbl_sid(),"
3693 		       " unable to determine packet's peer label\n");
3694 		return -EACCES;
3695 	}
3696 
3697 	return 0;
3698 }
3699 
3700 /* socket security operations */
3701 static int socket_has_perm(struct task_struct *task, struct socket *sock,
3702 			   u32 perms)
3703 {
3704 	struct inode_security_struct *isec;
3705 	struct common_audit_data ad;
3706 	u32 sid;
3707 	int err = 0;
3708 
3709 	isec = SOCK_INODE(sock)->i_security;
3710 
3711 	if (isec->sid == SECINITSID_KERNEL)
3712 		goto out;
3713 	sid = task_sid(task);
3714 
3715 	COMMON_AUDIT_DATA_INIT(&ad, NET);
3716 	ad.u.net.sk = sock->sk;
3717 	err = avc_has_perm(sid, isec->sid, isec->sclass, perms, &ad);
3718 
3719 out:
3720 	return err;
3721 }
3722 
3723 static int selinux_socket_create(int family, int type,
3724 				 int protocol, int kern)
3725 {
3726 	const struct cred *cred = current_cred();
3727 	const struct task_security_struct *tsec = cred->security;
3728 	u32 sid, newsid;
3729 	u16 secclass;
3730 	int err = 0;
3731 
3732 	if (kern)
3733 		goto out;
3734 
3735 	sid = tsec->sid;
3736 	newsid = tsec->sockcreate_sid ?: sid;
3737 
3738 	secclass = socket_type_to_security_class(family, type, protocol);
3739 	err = avc_has_perm(sid, newsid, secclass, SOCKET__CREATE, NULL);
3740 
3741 out:
3742 	return err;
3743 }
3744 
3745 static int selinux_socket_post_create(struct socket *sock, int family,
3746 				      int type, int protocol, int kern)
3747 {
3748 	const struct cred *cred = current_cred();
3749 	const struct task_security_struct *tsec = cred->security;
3750 	struct inode_security_struct *isec;
3751 	struct sk_security_struct *sksec;
3752 	u32 sid, newsid;
3753 	int err = 0;
3754 
3755 	sid = tsec->sid;
3756 	newsid = tsec->sockcreate_sid;
3757 
3758 	isec = SOCK_INODE(sock)->i_security;
3759 
3760 	if (kern)
3761 		isec->sid = SECINITSID_KERNEL;
3762 	else if (newsid)
3763 		isec->sid = newsid;
3764 	else
3765 		isec->sid = sid;
3766 
3767 	isec->sclass = socket_type_to_security_class(family, type, protocol);
3768 	isec->initialized = 1;
3769 
3770 	if (sock->sk) {
3771 		sksec = sock->sk->sk_security;
3772 		sksec->sid = isec->sid;
3773 		sksec->sclass = isec->sclass;
3774 		err = selinux_netlbl_socket_post_create(sock->sk, family);
3775 	}
3776 
3777 	return err;
3778 }
3779 
3780 /* Range of port numbers used to automatically bind.
3781    Need to determine whether we should perform a name_bind
3782    permission check between the socket and the port number. */
3783 
3784 static int selinux_socket_bind(struct socket *sock, struct sockaddr *address, int addrlen)
3785 {
3786 	u16 family;
3787 	int err;
3788 
3789 	err = socket_has_perm(current, sock, SOCKET__BIND);
3790 	if (err)
3791 		goto out;
3792 
3793 	/*
3794 	 * If PF_INET or PF_INET6, check name_bind permission for the port.
3795 	 * Multiple address binding for SCTP is not supported yet: we just
3796 	 * check the first address now.
3797 	 */
3798 	family = sock->sk->sk_family;
3799 	if (family == PF_INET || family == PF_INET6) {
3800 		char *addrp;
3801 		struct inode_security_struct *isec;
3802 		struct common_audit_data ad;
3803 		struct sockaddr_in *addr4 = NULL;
3804 		struct sockaddr_in6 *addr6 = NULL;
3805 		unsigned short snum;
3806 		struct sock *sk = sock->sk;
3807 		u32 sid, node_perm;
3808 
3809 		isec = SOCK_INODE(sock)->i_security;
3810 
3811 		if (family == PF_INET) {
3812 			addr4 = (struct sockaddr_in *)address;
3813 			snum = ntohs(addr4->sin_port);
3814 			addrp = (char *)&addr4->sin_addr.s_addr;
3815 		} else {
3816 			addr6 = (struct sockaddr_in6 *)address;
3817 			snum = ntohs(addr6->sin6_port);
3818 			addrp = (char *)&addr6->sin6_addr.s6_addr;
3819 		}
3820 
3821 		if (snum) {
3822 			int low, high;
3823 
3824 			inet_get_local_port_range(&low, &high);
3825 
3826 			if (snum < max(PROT_SOCK, low) || snum > high) {
3827 				err = sel_netport_sid(sk->sk_protocol,
3828 						      snum, &sid);
3829 				if (err)
3830 					goto out;
3831 				COMMON_AUDIT_DATA_INIT(&ad, NET);
3832 				ad.u.net.sport = htons(snum);
3833 				ad.u.net.family = family;
3834 				err = avc_has_perm(isec->sid, sid,
3835 						   isec->sclass,
3836 						   SOCKET__NAME_BIND, &ad);
3837 				if (err)
3838 					goto out;
3839 			}
3840 		}
3841 
3842 		switch (isec->sclass) {
3843 		case SECCLASS_TCP_SOCKET:
3844 			node_perm = TCP_SOCKET__NODE_BIND;
3845 			break;
3846 
3847 		case SECCLASS_UDP_SOCKET:
3848 			node_perm = UDP_SOCKET__NODE_BIND;
3849 			break;
3850 
3851 		case SECCLASS_DCCP_SOCKET:
3852 			node_perm = DCCP_SOCKET__NODE_BIND;
3853 			break;
3854 
3855 		default:
3856 			node_perm = RAWIP_SOCKET__NODE_BIND;
3857 			break;
3858 		}
3859 
3860 		err = sel_netnode_sid(addrp, family, &sid);
3861 		if (err)
3862 			goto out;
3863 
3864 		COMMON_AUDIT_DATA_INIT(&ad, NET);
3865 		ad.u.net.sport = htons(snum);
3866 		ad.u.net.family = family;
3867 
3868 		if (family == PF_INET)
3869 			ad.u.net.v4info.saddr = addr4->sin_addr.s_addr;
3870 		else
3871 			ipv6_addr_copy(&ad.u.net.v6info.saddr, &addr6->sin6_addr);
3872 
3873 		err = avc_has_perm(isec->sid, sid,
3874 				   isec->sclass, node_perm, &ad);
3875 		if (err)
3876 			goto out;
3877 	}
3878 out:
3879 	return err;
3880 }
3881 
3882 static int selinux_socket_connect(struct socket *sock, struct sockaddr *address, int addrlen)
3883 {
3884 	struct sock *sk = sock->sk;
3885 	struct inode_security_struct *isec;
3886 	int err;
3887 
3888 	err = socket_has_perm(current, sock, SOCKET__CONNECT);
3889 	if (err)
3890 		return err;
3891 
3892 	/*
3893 	 * If a TCP or DCCP socket, check name_connect permission for the port.
3894 	 */
3895 	isec = SOCK_INODE(sock)->i_security;
3896 	if (isec->sclass == SECCLASS_TCP_SOCKET ||
3897 	    isec->sclass == SECCLASS_DCCP_SOCKET) {
3898 		struct common_audit_data ad;
3899 		struct sockaddr_in *addr4 = NULL;
3900 		struct sockaddr_in6 *addr6 = NULL;
3901 		unsigned short snum;
3902 		u32 sid, perm;
3903 
3904 		if (sk->sk_family == PF_INET) {
3905 			addr4 = (struct sockaddr_in *)address;
3906 			if (addrlen < sizeof(struct sockaddr_in))
3907 				return -EINVAL;
3908 			snum = ntohs(addr4->sin_port);
3909 		} else {
3910 			addr6 = (struct sockaddr_in6 *)address;
3911 			if (addrlen < SIN6_LEN_RFC2133)
3912 				return -EINVAL;
3913 			snum = ntohs(addr6->sin6_port);
3914 		}
3915 
3916 		err = sel_netport_sid(sk->sk_protocol, snum, &sid);
3917 		if (err)
3918 			goto out;
3919 
3920 		perm = (isec->sclass == SECCLASS_TCP_SOCKET) ?
3921 		       TCP_SOCKET__NAME_CONNECT : DCCP_SOCKET__NAME_CONNECT;
3922 
3923 		COMMON_AUDIT_DATA_INIT(&ad, NET);
3924 		ad.u.net.dport = htons(snum);
3925 		ad.u.net.family = sk->sk_family;
3926 		err = avc_has_perm(isec->sid, sid, isec->sclass, perm, &ad);
3927 		if (err)
3928 			goto out;
3929 	}
3930 
3931 	err = selinux_netlbl_socket_connect(sk, address);
3932 
3933 out:
3934 	return err;
3935 }
3936 
3937 static int selinux_socket_listen(struct socket *sock, int backlog)
3938 {
3939 	return socket_has_perm(current, sock, SOCKET__LISTEN);
3940 }
3941 
3942 static int selinux_socket_accept(struct socket *sock, struct socket *newsock)
3943 {
3944 	int err;
3945 	struct inode_security_struct *isec;
3946 	struct inode_security_struct *newisec;
3947 
3948 	err = socket_has_perm(current, sock, SOCKET__ACCEPT);
3949 	if (err)
3950 		return err;
3951 
3952 	newisec = SOCK_INODE(newsock)->i_security;
3953 
3954 	isec = SOCK_INODE(sock)->i_security;
3955 	newisec->sclass = isec->sclass;
3956 	newisec->sid = isec->sid;
3957 	newisec->initialized = 1;
3958 
3959 	return 0;
3960 }
3961 
3962 static int selinux_socket_sendmsg(struct socket *sock, struct msghdr *msg,
3963 				  int size)
3964 {
3965 	return socket_has_perm(current, sock, SOCKET__WRITE);
3966 }
3967 
3968 static int selinux_socket_recvmsg(struct socket *sock, struct msghdr *msg,
3969 				  int size, int flags)
3970 {
3971 	return socket_has_perm(current, sock, SOCKET__READ);
3972 }
3973 
3974 static int selinux_socket_getsockname(struct socket *sock)
3975 {
3976 	return socket_has_perm(current, sock, SOCKET__GETATTR);
3977 }
3978 
3979 static int selinux_socket_getpeername(struct socket *sock)
3980 {
3981 	return socket_has_perm(current, sock, SOCKET__GETATTR);
3982 }
3983 
3984 static int selinux_socket_setsockopt(struct socket *sock, int level, int optname)
3985 {
3986 	int err;
3987 
3988 	err = socket_has_perm(current, sock, SOCKET__SETOPT);
3989 	if (err)
3990 		return err;
3991 
3992 	return selinux_netlbl_socket_setsockopt(sock, level, optname);
3993 }
3994 
3995 static int selinux_socket_getsockopt(struct socket *sock, int level,
3996 				     int optname)
3997 {
3998 	return socket_has_perm(current, sock, SOCKET__GETOPT);
3999 }
4000 
4001 static int selinux_socket_shutdown(struct socket *sock, int how)
4002 {
4003 	return socket_has_perm(current, sock, SOCKET__SHUTDOWN);
4004 }
4005 
4006 static int selinux_socket_unix_stream_connect(struct socket *sock,
4007 					      struct socket *other,
4008 					      struct sock *newsk)
4009 {
4010 	struct sk_security_struct *ssec;
4011 	struct inode_security_struct *isec;
4012 	struct inode_security_struct *other_isec;
4013 	struct common_audit_data ad;
4014 	int err;
4015 
4016 	isec = SOCK_INODE(sock)->i_security;
4017 	other_isec = SOCK_INODE(other)->i_security;
4018 
4019 	COMMON_AUDIT_DATA_INIT(&ad, NET);
4020 	ad.u.net.sk = other->sk;
4021 
4022 	err = avc_has_perm(isec->sid, other_isec->sid,
4023 			   isec->sclass,
4024 			   UNIX_STREAM_SOCKET__CONNECTTO, &ad);
4025 	if (err)
4026 		return err;
4027 
4028 	/* connecting socket */
4029 	ssec = sock->sk->sk_security;
4030 	ssec->peer_sid = other_isec->sid;
4031 
4032 	/* server child socket */
4033 	ssec = newsk->sk_security;
4034 	ssec->peer_sid = isec->sid;
4035 	err = security_sid_mls_copy(other_isec->sid, ssec->peer_sid, &ssec->sid);
4036 
4037 	return err;
4038 }
4039 
4040 static int selinux_socket_unix_may_send(struct socket *sock,
4041 					struct socket *other)
4042 {
4043 	struct inode_security_struct *isec;
4044 	struct inode_security_struct *other_isec;
4045 	struct common_audit_data ad;
4046 	int err;
4047 
4048 	isec = SOCK_INODE(sock)->i_security;
4049 	other_isec = SOCK_INODE(other)->i_security;
4050 
4051 	COMMON_AUDIT_DATA_INIT(&ad, NET);
4052 	ad.u.net.sk = other->sk;
4053 
4054 	err = avc_has_perm(isec->sid, other_isec->sid,
4055 			   isec->sclass, SOCKET__SENDTO, &ad);
4056 	if (err)
4057 		return err;
4058 
4059 	return 0;
4060 }
4061 
4062 static int selinux_inet_sys_rcv_skb(int ifindex, char *addrp, u16 family,
4063 				    u32 peer_sid,
4064 				    struct common_audit_data *ad)
4065 {
4066 	int err;
4067 	u32 if_sid;
4068 	u32 node_sid;
4069 
4070 	err = sel_netif_sid(ifindex, &if_sid);
4071 	if (err)
4072 		return err;
4073 	err = avc_has_perm(peer_sid, if_sid,
4074 			   SECCLASS_NETIF, NETIF__INGRESS, ad);
4075 	if (err)
4076 		return err;
4077 
4078 	err = sel_netnode_sid(addrp, family, &node_sid);
4079 	if (err)
4080 		return err;
4081 	return avc_has_perm(peer_sid, node_sid,
4082 			    SECCLASS_NODE, NODE__RECVFROM, ad);
4083 }
4084 
4085 static int selinux_sock_rcv_skb_compat(struct sock *sk, struct sk_buff *skb,
4086 				       u16 family)
4087 {
4088 	int err = 0;
4089 	struct sk_security_struct *sksec = sk->sk_security;
4090 	u32 peer_sid;
4091 	u32 sk_sid = sksec->sid;
4092 	struct common_audit_data ad;
4093 	char *addrp;
4094 
4095 	COMMON_AUDIT_DATA_INIT(&ad, NET);
4096 	ad.u.net.netif = skb->skb_iif;
4097 	ad.u.net.family = family;
4098 	err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL);
4099 	if (err)
4100 		return err;
4101 
4102 	if (selinux_secmark_enabled()) {
4103 		err = avc_has_perm(sk_sid, skb->secmark, SECCLASS_PACKET,
4104 				   PACKET__RECV, &ad);
4105 		if (err)
4106 			return err;
4107 	}
4108 
4109 	if (selinux_policycap_netpeer) {
4110 		err = selinux_skb_peerlbl_sid(skb, family, &peer_sid);
4111 		if (err)
4112 			return err;
4113 		err = avc_has_perm(sk_sid, peer_sid,
4114 				   SECCLASS_PEER, PEER__RECV, &ad);
4115 		if (err)
4116 			selinux_netlbl_err(skb, err, 0);
4117 	} else {
4118 		err = selinux_netlbl_sock_rcv_skb(sksec, skb, family, &ad);
4119 		if (err)
4120 			return err;
4121 		err = selinux_xfrm_sock_rcv_skb(sksec->sid, skb, &ad);
4122 	}
4123 
4124 	return err;
4125 }
4126 
4127 static int selinux_socket_sock_rcv_skb(struct sock *sk, struct sk_buff *skb)
4128 {
4129 	int err;
4130 	struct sk_security_struct *sksec = sk->sk_security;
4131 	u16 family = sk->sk_family;
4132 	u32 sk_sid = sksec->sid;
4133 	struct common_audit_data ad;
4134 	char *addrp;
4135 	u8 secmark_active;
4136 	u8 peerlbl_active;
4137 
4138 	if (family != PF_INET && family != PF_INET6)
4139 		return 0;
4140 
4141 	/* Handle mapped IPv4 packets arriving via IPv6 sockets */
4142 	if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
4143 		family = PF_INET;
4144 
4145 	/* If any sort of compatibility mode is enabled then handoff processing
4146 	 * to the selinux_sock_rcv_skb_compat() function to deal with the
4147 	 * special handling.  We do this in an attempt to keep this function
4148 	 * as fast and as clean as possible. */
4149 	if (!selinux_policycap_netpeer)
4150 		return selinux_sock_rcv_skb_compat(sk, skb, family);
4151 
4152 	secmark_active = selinux_secmark_enabled();
4153 	peerlbl_active = netlbl_enabled() || selinux_xfrm_enabled();
4154 	if (!secmark_active && !peerlbl_active)
4155 		return 0;
4156 
4157 	COMMON_AUDIT_DATA_INIT(&ad, NET);
4158 	ad.u.net.netif = skb->skb_iif;
4159 	ad.u.net.family = family;
4160 	err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL);
4161 	if (err)
4162 		return err;
4163 
4164 	if (peerlbl_active) {
4165 		u32 peer_sid;
4166 
4167 		err = selinux_skb_peerlbl_sid(skb, family, &peer_sid);
4168 		if (err)
4169 			return err;
4170 		err = selinux_inet_sys_rcv_skb(skb->skb_iif, addrp, family,
4171 					       peer_sid, &ad);
4172 		if (err) {
4173 			selinux_netlbl_err(skb, err, 0);
4174 			return err;
4175 		}
4176 		err = avc_has_perm(sk_sid, peer_sid, SECCLASS_PEER,
4177 				   PEER__RECV, &ad);
4178 		if (err)
4179 			selinux_netlbl_err(skb, err, 0);
4180 	}
4181 
4182 	if (secmark_active) {
4183 		err = avc_has_perm(sk_sid, skb->secmark, SECCLASS_PACKET,
4184 				   PACKET__RECV, &ad);
4185 		if (err)
4186 			return err;
4187 	}
4188 
4189 	return err;
4190 }
4191 
4192 static int selinux_socket_getpeersec_stream(struct socket *sock, char __user *optval,
4193 					    int __user *optlen, unsigned len)
4194 {
4195 	int err = 0;
4196 	char *scontext;
4197 	u32 scontext_len;
4198 	struct sk_security_struct *ssec;
4199 	struct inode_security_struct *isec;
4200 	u32 peer_sid = SECSID_NULL;
4201 
4202 	isec = SOCK_INODE(sock)->i_security;
4203 
4204 	if (isec->sclass == SECCLASS_UNIX_STREAM_SOCKET ||
4205 	    isec->sclass == SECCLASS_TCP_SOCKET) {
4206 		ssec = sock->sk->sk_security;
4207 		peer_sid = ssec->peer_sid;
4208 	}
4209 	if (peer_sid == SECSID_NULL) {
4210 		err = -ENOPROTOOPT;
4211 		goto out;
4212 	}
4213 
4214 	err = security_sid_to_context(peer_sid, &scontext, &scontext_len);
4215 
4216 	if (err)
4217 		goto out;
4218 
4219 	if (scontext_len > len) {
4220 		err = -ERANGE;
4221 		goto out_len;
4222 	}
4223 
4224 	if (copy_to_user(optval, scontext, scontext_len))
4225 		err = -EFAULT;
4226 
4227 out_len:
4228 	if (put_user(scontext_len, optlen))
4229 		err = -EFAULT;
4230 
4231 	kfree(scontext);
4232 out:
4233 	return err;
4234 }
4235 
4236 static int selinux_socket_getpeersec_dgram(struct socket *sock, struct sk_buff *skb, u32 *secid)
4237 {
4238 	u32 peer_secid = SECSID_NULL;
4239 	u16 family;
4240 
4241 	if (skb && skb->protocol == htons(ETH_P_IP))
4242 		family = PF_INET;
4243 	else if (skb && skb->protocol == htons(ETH_P_IPV6))
4244 		family = PF_INET6;
4245 	else if (sock)
4246 		family = sock->sk->sk_family;
4247 	else
4248 		goto out;
4249 
4250 	if (sock && family == PF_UNIX)
4251 		selinux_inode_getsecid(SOCK_INODE(sock), &peer_secid);
4252 	else if (skb)
4253 		selinux_skb_peerlbl_sid(skb, family, &peer_secid);
4254 
4255 out:
4256 	*secid = peer_secid;
4257 	if (peer_secid == SECSID_NULL)
4258 		return -EINVAL;
4259 	return 0;
4260 }
4261 
4262 static int selinux_sk_alloc_security(struct sock *sk, int family, gfp_t priority)
4263 {
4264 	return sk_alloc_security(sk, family, priority);
4265 }
4266 
4267 static void selinux_sk_free_security(struct sock *sk)
4268 {
4269 	sk_free_security(sk);
4270 }
4271 
4272 static void selinux_sk_clone_security(const struct sock *sk, struct sock *newsk)
4273 {
4274 	struct sk_security_struct *ssec = sk->sk_security;
4275 	struct sk_security_struct *newssec = newsk->sk_security;
4276 
4277 	newssec->sid = ssec->sid;
4278 	newssec->peer_sid = ssec->peer_sid;
4279 	newssec->sclass = ssec->sclass;
4280 
4281 	selinux_netlbl_sk_security_reset(newssec);
4282 }
4283 
4284 static void selinux_sk_getsecid(struct sock *sk, u32 *secid)
4285 {
4286 	if (!sk)
4287 		*secid = SECINITSID_ANY_SOCKET;
4288 	else {
4289 		struct sk_security_struct *sksec = sk->sk_security;
4290 
4291 		*secid = sksec->sid;
4292 	}
4293 }
4294 
4295 static void selinux_sock_graft(struct sock *sk, struct socket *parent)
4296 {
4297 	struct inode_security_struct *isec = SOCK_INODE(parent)->i_security;
4298 	struct sk_security_struct *sksec = sk->sk_security;
4299 
4300 	if (sk->sk_family == PF_INET || sk->sk_family == PF_INET6 ||
4301 	    sk->sk_family == PF_UNIX)
4302 		isec->sid = sksec->sid;
4303 	sksec->sclass = isec->sclass;
4304 }
4305 
4306 static int selinux_inet_conn_request(struct sock *sk, struct sk_buff *skb,
4307 				     struct request_sock *req)
4308 {
4309 	struct sk_security_struct *sksec = sk->sk_security;
4310 	int err;
4311 	u16 family = sk->sk_family;
4312 	u32 newsid;
4313 	u32 peersid;
4314 
4315 	/* handle mapped IPv4 packets arriving via IPv6 sockets */
4316 	if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
4317 		family = PF_INET;
4318 
4319 	err = selinux_skb_peerlbl_sid(skb, family, &peersid);
4320 	if (err)
4321 		return err;
4322 	if (peersid == SECSID_NULL) {
4323 		req->secid = sksec->sid;
4324 		req->peer_secid = SECSID_NULL;
4325 	} else {
4326 		err = security_sid_mls_copy(sksec->sid, peersid, &newsid);
4327 		if (err)
4328 			return err;
4329 		req->secid = newsid;
4330 		req->peer_secid = peersid;
4331 	}
4332 
4333 	return selinux_netlbl_inet_conn_request(req, family);
4334 }
4335 
4336 static void selinux_inet_csk_clone(struct sock *newsk,
4337 				   const struct request_sock *req)
4338 {
4339 	struct sk_security_struct *newsksec = newsk->sk_security;
4340 
4341 	newsksec->sid = req->secid;
4342 	newsksec->peer_sid = req->peer_secid;
4343 	/* NOTE: Ideally, we should also get the isec->sid for the
4344 	   new socket in sync, but we don't have the isec available yet.
4345 	   So we will wait until sock_graft to do it, by which
4346 	   time it will have been created and available. */
4347 
4348 	/* We don't need to take any sort of lock here as we are the only
4349 	 * thread with access to newsksec */
4350 	selinux_netlbl_inet_csk_clone(newsk, req->rsk_ops->family);
4351 }
4352 
4353 static void selinux_inet_conn_established(struct sock *sk, struct sk_buff *skb)
4354 {
4355 	u16 family = sk->sk_family;
4356 	struct sk_security_struct *sksec = sk->sk_security;
4357 
4358 	/* handle mapped IPv4 packets arriving via IPv6 sockets */
4359 	if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
4360 		family = PF_INET;
4361 
4362 	selinux_skb_peerlbl_sid(skb, family, &sksec->peer_sid);
4363 }
4364 
4365 static void selinux_req_classify_flow(const struct request_sock *req,
4366 				      struct flowi *fl)
4367 {
4368 	fl->secid = req->secid;
4369 }
4370 
4371 static int selinux_tun_dev_create(void)
4372 {
4373 	u32 sid = current_sid();
4374 
4375 	/* we aren't taking into account the "sockcreate" SID since the socket
4376 	 * that is being created here is not a socket in the traditional sense,
4377 	 * instead it is a private sock, accessible only to the kernel, and
4378 	 * representing a wide range of network traffic spanning multiple
4379 	 * connections unlike traditional sockets - check the TUN driver to
4380 	 * get a better understanding of why this socket is special */
4381 
4382 	return avc_has_perm(sid, sid, SECCLASS_TUN_SOCKET, TUN_SOCKET__CREATE,
4383 			    NULL);
4384 }
4385 
4386 static void selinux_tun_dev_post_create(struct sock *sk)
4387 {
4388 	struct sk_security_struct *sksec = sk->sk_security;
4389 
4390 	/* we don't currently perform any NetLabel based labeling here and it
4391 	 * isn't clear that we would want to do so anyway; while we could apply
4392 	 * labeling without the support of the TUN user the resulting labeled
4393 	 * traffic from the other end of the connection would almost certainly
4394 	 * cause confusion to the TUN user that had no idea network labeling
4395 	 * protocols were being used */
4396 
4397 	/* see the comments in selinux_tun_dev_create() about why we don't use
4398 	 * the sockcreate SID here */
4399 
4400 	sksec->sid = current_sid();
4401 	sksec->sclass = SECCLASS_TUN_SOCKET;
4402 }
4403 
4404 static int selinux_tun_dev_attach(struct sock *sk)
4405 {
4406 	struct sk_security_struct *sksec = sk->sk_security;
4407 	u32 sid = current_sid();
4408 	int err;
4409 
4410 	err = avc_has_perm(sid, sksec->sid, SECCLASS_TUN_SOCKET,
4411 			   TUN_SOCKET__RELABELFROM, NULL);
4412 	if (err)
4413 		return err;
4414 	err = avc_has_perm(sid, sid, SECCLASS_TUN_SOCKET,
4415 			   TUN_SOCKET__RELABELTO, NULL);
4416 	if (err)
4417 		return err;
4418 
4419 	sksec->sid = sid;
4420 
4421 	return 0;
4422 }
4423 
4424 static int selinux_nlmsg_perm(struct sock *sk, struct sk_buff *skb)
4425 {
4426 	int err = 0;
4427 	u32 perm;
4428 	struct nlmsghdr *nlh;
4429 	struct socket *sock = sk->sk_socket;
4430 	struct inode_security_struct *isec = SOCK_INODE(sock)->i_security;
4431 
4432 	if (skb->len < NLMSG_SPACE(0)) {
4433 		err = -EINVAL;
4434 		goto out;
4435 	}
4436 	nlh = nlmsg_hdr(skb);
4437 
4438 	err = selinux_nlmsg_lookup(isec->sclass, nlh->nlmsg_type, &perm);
4439 	if (err) {
4440 		if (err == -EINVAL) {
4441 			audit_log(current->audit_context, GFP_KERNEL, AUDIT_SELINUX_ERR,
4442 				  "SELinux:  unrecognized netlink message"
4443 				  " type=%hu for sclass=%hu\n",
4444 				  nlh->nlmsg_type, isec->sclass);
4445 			if (!selinux_enforcing || security_get_allow_unknown())
4446 				err = 0;
4447 		}
4448 
4449 		/* Ignore */
4450 		if (err == -ENOENT)
4451 			err = 0;
4452 		goto out;
4453 	}
4454 
4455 	err = socket_has_perm(current, sock, perm);
4456 out:
4457 	return err;
4458 }
4459 
4460 #ifdef CONFIG_NETFILTER
4461 
4462 static unsigned int selinux_ip_forward(struct sk_buff *skb, int ifindex,
4463 				       u16 family)
4464 {
4465 	int err;
4466 	char *addrp;
4467 	u32 peer_sid;
4468 	struct common_audit_data ad;
4469 	u8 secmark_active;
4470 	u8 netlbl_active;
4471 	u8 peerlbl_active;
4472 
4473 	if (!selinux_policycap_netpeer)
4474 		return NF_ACCEPT;
4475 
4476 	secmark_active = selinux_secmark_enabled();
4477 	netlbl_active = netlbl_enabled();
4478 	peerlbl_active = netlbl_active || selinux_xfrm_enabled();
4479 	if (!secmark_active && !peerlbl_active)
4480 		return NF_ACCEPT;
4481 
4482 	if (selinux_skb_peerlbl_sid(skb, family, &peer_sid) != 0)
4483 		return NF_DROP;
4484 
4485 	COMMON_AUDIT_DATA_INIT(&ad, NET);
4486 	ad.u.net.netif = ifindex;
4487 	ad.u.net.family = family;
4488 	if (selinux_parse_skb(skb, &ad, &addrp, 1, NULL) != 0)
4489 		return NF_DROP;
4490 
4491 	if (peerlbl_active) {
4492 		err = selinux_inet_sys_rcv_skb(ifindex, addrp, family,
4493 					       peer_sid, &ad);
4494 		if (err) {
4495 			selinux_netlbl_err(skb, err, 1);
4496 			return NF_DROP;
4497 		}
4498 	}
4499 
4500 	if (secmark_active)
4501 		if (avc_has_perm(peer_sid, skb->secmark,
4502 				 SECCLASS_PACKET, PACKET__FORWARD_IN, &ad))
4503 			return NF_DROP;
4504 
4505 	if (netlbl_active)
4506 		/* we do this in the FORWARD path and not the POST_ROUTING
4507 		 * path because we want to make sure we apply the necessary
4508 		 * labeling before IPsec is applied so we can leverage AH
4509 		 * protection */
4510 		if (selinux_netlbl_skbuff_setsid(skb, family, peer_sid) != 0)
4511 			return NF_DROP;
4512 
4513 	return NF_ACCEPT;
4514 }
4515 
4516 static unsigned int selinux_ipv4_forward(unsigned int hooknum,
4517 					 struct sk_buff *skb,
4518 					 const struct net_device *in,
4519 					 const struct net_device *out,
4520 					 int (*okfn)(struct sk_buff *))
4521 {
4522 	return selinux_ip_forward(skb, in->ifindex, PF_INET);
4523 }
4524 
4525 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
4526 static unsigned int selinux_ipv6_forward(unsigned int hooknum,
4527 					 struct sk_buff *skb,
4528 					 const struct net_device *in,
4529 					 const struct net_device *out,
4530 					 int (*okfn)(struct sk_buff *))
4531 {
4532 	return selinux_ip_forward(skb, in->ifindex, PF_INET6);
4533 }
4534 #endif	/* IPV6 */
4535 
4536 static unsigned int selinux_ip_output(struct sk_buff *skb,
4537 				      u16 family)
4538 {
4539 	u32 sid;
4540 
4541 	if (!netlbl_enabled())
4542 		return NF_ACCEPT;
4543 
4544 	/* we do this in the LOCAL_OUT path and not the POST_ROUTING path
4545 	 * because we want to make sure we apply the necessary labeling
4546 	 * before IPsec is applied so we can leverage AH protection */
4547 	if (skb->sk) {
4548 		struct sk_security_struct *sksec = skb->sk->sk_security;
4549 		sid = sksec->sid;
4550 	} else
4551 		sid = SECINITSID_KERNEL;
4552 	if (selinux_netlbl_skbuff_setsid(skb, family, sid) != 0)
4553 		return NF_DROP;
4554 
4555 	return NF_ACCEPT;
4556 }
4557 
4558 static unsigned int selinux_ipv4_output(unsigned int hooknum,
4559 					struct sk_buff *skb,
4560 					const struct net_device *in,
4561 					const struct net_device *out,
4562 					int (*okfn)(struct sk_buff *))
4563 {
4564 	return selinux_ip_output(skb, PF_INET);
4565 }
4566 
4567 static unsigned int selinux_ip_postroute_compat(struct sk_buff *skb,
4568 						int ifindex,
4569 						u16 family)
4570 {
4571 	struct sock *sk = skb->sk;
4572 	struct sk_security_struct *sksec;
4573 	struct common_audit_data ad;
4574 	char *addrp;
4575 	u8 proto;
4576 
4577 	if (sk == NULL)
4578 		return NF_ACCEPT;
4579 	sksec = sk->sk_security;
4580 
4581 	COMMON_AUDIT_DATA_INIT(&ad, NET);
4582 	ad.u.net.netif = ifindex;
4583 	ad.u.net.family = family;
4584 	if (selinux_parse_skb(skb, &ad, &addrp, 0, &proto))
4585 		return NF_DROP;
4586 
4587 	if (selinux_secmark_enabled())
4588 		if (avc_has_perm(sksec->sid, skb->secmark,
4589 				 SECCLASS_PACKET, PACKET__SEND, &ad))
4590 			return NF_DROP;
4591 
4592 	if (selinux_policycap_netpeer)
4593 		if (selinux_xfrm_postroute_last(sksec->sid, skb, &ad, proto))
4594 			return NF_DROP;
4595 
4596 	return NF_ACCEPT;
4597 }
4598 
4599 static unsigned int selinux_ip_postroute(struct sk_buff *skb, int ifindex,
4600 					 u16 family)
4601 {
4602 	u32 secmark_perm;
4603 	u32 peer_sid;
4604 	struct sock *sk;
4605 	struct common_audit_data ad;
4606 	char *addrp;
4607 	u8 secmark_active;
4608 	u8 peerlbl_active;
4609 
4610 	/* If any sort of compatibility mode is enabled then handoff processing
4611 	 * to the selinux_ip_postroute_compat() function to deal with the
4612 	 * special handling.  We do this in an attempt to keep this function
4613 	 * as fast and as clean as possible. */
4614 	if (!selinux_policycap_netpeer)
4615 		return selinux_ip_postroute_compat(skb, ifindex, family);
4616 #ifdef CONFIG_XFRM
4617 	/* If skb->dst->xfrm is non-NULL then the packet is undergoing an IPsec
4618 	 * packet transformation so allow the packet to pass without any checks
4619 	 * since we'll have another chance to perform access control checks
4620 	 * when the packet is on it's final way out.
4621 	 * NOTE: there appear to be some IPv6 multicast cases where skb->dst
4622 	 *       is NULL, in this case go ahead and apply access control. */
4623 	if (skb_dst(skb) != NULL && skb_dst(skb)->xfrm != NULL)
4624 		return NF_ACCEPT;
4625 #endif
4626 	secmark_active = selinux_secmark_enabled();
4627 	peerlbl_active = netlbl_enabled() || selinux_xfrm_enabled();
4628 	if (!secmark_active && !peerlbl_active)
4629 		return NF_ACCEPT;
4630 
4631 	/* if the packet is being forwarded then get the peer label from the
4632 	 * packet itself; otherwise check to see if it is from a local
4633 	 * application or the kernel, if from an application get the peer label
4634 	 * from the sending socket, otherwise use the kernel's sid */
4635 	sk = skb->sk;
4636 	if (sk == NULL) {
4637 		switch (family) {
4638 		case PF_INET:
4639 			if (IPCB(skb)->flags & IPSKB_FORWARDED)
4640 				secmark_perm = PACKET__FORWARD_OUT;
4641 			else
4642 				secmark_perm = PACKET__SEND;
4643 			break;
4644 		case PF_INET6:
4645 			if (IP6CB(skb)->flags & IP6SKB_FORWARDED)
4646 				secmark_perm = PACKET__FORWARD_OUT;
4647 			else
4648 				secmark_perm = PACKET__SEND;
4649 			break;
4650 		default:
4651 			return NF_DROP;
4652 		}
4653 		if (secmark_perm == PACKET__FORWARD_OUT) {
4654 			if (selinux_skb_peerlbl_sid(skb, family, &peer_sid))
4655 				return NF_DROP;
4656 		} else
4657 			peer_sid = SECINITSID_KERNEL;
4658 	} else {
4659 		struct sk_security_struct *sksec = sk->sk_security;
4660 		peer_sid = sksec->sid;
4661 		secmark_perm = PACKET__SEND;
4662 	}
4663 
4664 	COMMON_AUDIT_DATA_INIT(&ad, NET);
4665 	ad.u.net.netif = ifindex;
4666 	ad.u.net.family = family;
4667 	if (selinux_parse_skb(skb, &ad, &addrp, 0, NULL))
4668 		return NF_DROP;
4669 
4670 	if (secmark_active)
4671 		if (avc_has_perm(peer_sid, skb->secmark,
4672 				 SECCLASS_PACKET, secmark_perm, &ad))
4673 			return NF_DROP;
4674 
4675 	if (peerlbl_active) {
4676 		u32 if_sid;
4677 		u32 node_sid;
4678 
4679 		if (sel_netif_sid(ifindex, &if_sid))
4680 			return NF_DROP;
4681 		if (avc_has_perm(peer_sid, if_sid,
4682 				 SECCLASS_NETIF, NETIF__EGRESS, &ad))
4683 			return NF_DROP;
4684 
4685 		if (sel_netnode_sid(addrp, family, &node_sid))
4686 			return NF_DROP;
4687 		if (avc_has_perm(peer_sid, node_sid,
4688 				 SECCLASS_NODE, NODE__SENDTO, &ad))
4689 			return NF_DROP;
4690 	}
4691 
4692 	return NF_ACCEPT;
4693 }
4694 
4695 static unsigned int selinux_ipv4_postroute(unsigned int hooknum,
4696 					   struct sk_buff *skb,
4697 					   const struct net_device *in,
4698 					   const struct net_device *out,
4699 					   int (*okfn)(struct sk_buff *))
4700 {
4701 	return selinux_ip_postroute(skb, out->ifindex, PF_INET);
4702 }
4703 
4704 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
4705 static unsigned int selinux_ipv6_postroute(unsigned int hooknum,
4706 					   struct sk_buff *skb,
4707 					   const struct net_device *in,
4708 					   const struct net_device *out,
4709 					   int (*okfn)(struct sk_buff *))
4710 {
4711 	return selinux_ip_postroute(skb, out->ifindex, PF_INET6);
4712 }
4713 #endif	/* IPV6 */
4714 
4715 #endif	/* CONFIG_NETFILTER */
4716 
4717 static int selinux_netlink_send(struct sock *sk, struct sk_buff *skb)
4718 {
4719 	int err;
4720 
4721 	err = cap_netlink_send(sk, skb);
4722 	if (err)
4723 		return err;
4724 
4725 	return selinux_nlmsg_perm(sk, skb);
4726 }
4727 
4728 static int selinux_netlink_recv(struct sk_buff *skb, int capability)
4729 {
4730 	int err;
4731 	struct common_audit_data ad;
4732 
4733 	err = cap_netlink_recv(skb, capability);
4734 	if (err)
4735 		return err;
4736 
4737 	COMMON_AUDIT_DATA_INIT(&ad, CAP);
4738 	ad.u.cap = capability;
4739 
4740 	return avc_has_perm(NETLINK_CB(skb).sid, NETLINK_CB(skb).sid,
4741 			    SECCLASS_CAPABILITY, CAP_TO_MASK(capability), &ad);
4742 }
4743 
4744 static int ipc_alloc_security(struct task_struct *task,
4745 			      struct kern_ipc_perm *perm,
4746 			      u16 sclass)
4747 {
4748 	struct ipc_security_struct *isec;
4749 	u32 sid;
4750 
4751 	isec = kzalloc(sizeof(struct ipc_security_struct), GFP_KERNEL);
4752 	if (!isec)
4753 		return -ENOMEM;
4754 
4755 	sid = task_sid(task);
4756 	isec->sclass = sclass;
4757 	isec->sid = sid;
4758 	perm->security = isec;
4759 
4760 	return 0;
4761 }
4762 
4763 static void ipc_free_security(struct kern_ipc_perm *perm)
4764 {
4765 	struct ipc_security_struct *isec = perm->security;
4766 	perm->security = NULL;
4767 	kfree(isec);
4768 }
4769 
4770 static int msg_msg_alloc_security(struct msg_msg *msg)
4771 {
4772 	struct msg_security_struct *msec;
4773 
4774 	msec = kzalloc(sizeof(struct msg_security_struct), GFP_KERNEL);
4775 	if (!msec)
4776 		return -ENOMEM;
4777 
4778 	msec->sid = SECINITSID_UNLABELED;
4779 	msg->security = msec;
4780 
4781 	return 0;
4782 }
4783 
4784 static void msg_msg_free_security(struct msg_msg *msg)
4785 {
4786 	struct msg_security_struct *msec = msg->security;
4787 
4788 	msg->security = NULL;
4789 	kfree(msec);
4790 }
4791 
4792 static int ipc_has_perm(struct kern_ipc_perm *ipc_perms,
4793 			u32 perms)
4794 {
4795 	struct ipc_security_struct *isec;
4796 	struct common_audit_data ad;
4797 	u32 sid = current_sid();
4798 
4799 	isec = ipc_perms->security;
4800 
4801 	COMMON_AUDIT_DATA_INIT(&ad, IPC);
4802 	ad.u.ipc_id = ipc_perms->key;
4803 
4804 	return avc_has_perm(sid, isec->sid, isec->sclass, perms, &ad);
4805 }
4806 
4807 static int selinux_msg_msg_alloc_security(struct msg_msg *msg)
4808 {
4809 	return msg_msg_alloc_security(msg);
4810 }
4811 
4812 static void selinux_msg_msg_free_security(struct msg_msg *msg)
4813 {
4814 	msg_msg_free_security(msg);
4815 }
4816 
4817 /* message queue security operations */
4818 static int selinux_msg_queue_alloc_security(struct msg_queue *msq)
4819 {
4820 	struct ipc_security_struct *isec;
4821 	struct common_audit_data ad;
4822 	u32 sid = current_sid();
4823 	int rc;
4824 
4825 	rc = ipc_alloc_security(current, &msq->q_perm, SECCLASS_MSGQ);
4826 	if (rc)
4827 		return rc;
4828 
4829 	isec = msq->q_perm.security;
4830 
4831 	COMMON_AUDIT_DATA_INIT(&ad, IPC);
4832 	ad.u.ipc_id = msq->q_perm.key;
4833 
4834 	rc = avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
4835 			  MSGQ__CREATE, &ad);
4836 	if (rc) {
4837 		ipc_free_security(&msq->q_perm);
4838 		return rc;
4839 	}
4840 	return 0;
4841 }
4842 
4843 static void selinux_msg_queue_free_security(struct msg_queue *msq)
4844 {
4845 	ipc_free_security(&msq->q_perm);
4846 }
4847 
4848 static int selinux_msg_queue_associate(struct msg_queue *msq, int msqflg)
4849 {
4850 	struct ipc_security_struct *isec;
4851 	struct common_audit_data ad;
4852 	u32 sid = current_sid();
4853 
4854 	isec = msq->q_perm.security;
4855 
4856 	COMMON_AUDIT_DATA_INIT(&ad, IPC);
4857 	ad.u.ipc_id = msq->q_perm.key;
4858 
4859 	return avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
4860 			    MSGQ__ASSOCIATE, &ad);
4861 }
4862 
4863 static int selinux_msg_queue_msgctl(struct msg_queue *msq, int cmd)
4864 {
4865 	int err;
4866 	int perms;
4867 
4868 	switch (cmd) {
4869 	case IPC_INFO:
4870 	case MSG_INFO:
4871 		/* No specific object, just general system-wide information. */
4872 		return task_has_system(current, SYSTEM__IPC_INFO);
4873 	case IPC_STAT:
4874 	case MSG_STAT:
4875 		perms = MSGQ__GETATTR | MSGQ__ASSOCIATE;
4876 		break;
4877 	case IPC_SET:
4878 		perms = MSGQ__SETATTR;
4879 		break;
4880 	case IPC_RMID:
4881 		perms = MSGQ__DESTROY;
4882 		break;
4883 	default:
4884 		return 0;
4885 	}
4886 
4887 	err = ipc_has_perm(&msq->q_perm, perms);
4888 	return err;
4889 }
4890 
4891 static int selinux_msg_queue_msgsnd(struct msg_queue *msq, struct msg_msg *msg, int msqflg)
4892 {
4893 	struct ipc_security_struct *isec;
4894 	struct msg_security_struct *msec;
4895 	struct common_audit_data ad;
4896 	u32 sid = current_sid();
4897 	int rc;
4898 
4899 	isec = msq->q_perm.security;
4900 	msec = msg->security;
4901 
4902 	/*
4903 	 * First time through, need to assign label to the message
4904 	 */
4905 	if (msec->sid == SECINITSID_UNLABELED) {
4906 		/*
4907 		 * Compute new sid based on current process and
4908 		 * message queue this message will be stored in
4909 		 */
4910 		rc = security_transition_sid(sid, isec->sid, SECCLASS_MSG,
4911 					     &msec->sid);
4912 		if (rc)
4913 			return rc;
4914 	}
4915 
4916 	COMMON_AUDIT_DATA_INIT(&ad, IPC);
4917 	ad.u.ipc_id = msq->q_perm.key;
4918 
4919 	/* Can this process write to the queue? */
4920 	rc = avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
4921 			  MSGQ__WRITE, &ad);
4922 	if (!rc)
4923 		/* Can this process send the message */
4924 		rc = avc_has_perm(sid, msec->sid, SECCLASS_MSG,
4925 				  MSG__SEND, &ad);
4926 	if (!rc)
4927 		/* Can the message be put in the queue? */
4928 		rc = avc_has_perm(msec->sid, isec->sid, SECCLASS_MSGQ,
4929 				  MSGQ__ENQUEUE, &ad);
4930 
4931 	return rc;
4932 }
4933 
4934 static int selinux_msg_queue_msgrcv(struct msg_queue *msq, struct msg_msg *msg,
4935 				    struct task_struct *target,
4936 				    long type, int mode)
4937 {
4938 	struct ipc_security_struct *isec;
4939 	struct msg_security_struct *msec;
4940 	struct common_audit_data ad;
4941 	u32 sid = task_sid(target);
4942 	int rc;
4943 
4944 	isec = msq->q_perm.security;
4945 	msec = msg->security;
4946 
4947 	COMMON_AUDIT_DATA_INIT(&ad, IPC);
4948 	ad.u.ipc_id = msq->q_perm.key;
4949 
4950 	rc = avc_has_perm(sid, isec->sid,
4951 			  SECCLASS_MSGQ, MSGQ__READ, &ad);
4952 	if (!rc)
4953 		rc = avc_has_perm(sid, msec->sid,
4954 				  SECCLASS_MSG, MSG__RECEIVE, &ad);
4955 	return rc;
4956 }
4957 
4958 /* Shared Memory security operations */
4959 static int selinux_shm_alloc_security(struct shmid_kernel *shp)
4960 {
4961 	struct ipc_security_struct *isec;
4962 	struct common_audit_data ad;
4963 	u32 sid = current_sid();
4964 	int rc;
4965 
4966 	rc = ipc_alloc_security(current, &shp->shm_perm, SECCLASS_SHM);
4967 	if (rc)
4968 		return rc;
4969 
4970 	isec = shp->shm_perm.security;
4971 
4972 	COMMON_AUDIT_DATA_INIT(&ad, IPC);
4973 	ad.u.ipc_id = shp->shm_perm.key;
4974 
4975 	rc = avc_has_perm(sid, isec->sid, SECCLASS_SHM,
4976 			  SHM__CREATE, &ad);
4977 	if (rc) {
4978 		ipc_free_security(&shp->shm_perm);
4979 		return rc;
4980 	}
4981 	return 0;
4982 }
4983 
4984 static void selinux_shm_free_security(struct shmid_kernel *shp)
4985 {
4986 	ipc_free_security(&shp->shm_perm);
4987 }
4988 
4989 static int selinux_shm_associate(struct shmid_kernel *shp, int shmflg)
4990 {
4991 	struct ipc_security_struct *isec;
4992 	struct common_audit_data ad;
4993 	u32 sid = current_sid();
4994 
4995 	isec = shp->shm_perm.security;
4996 
4997 	COMMON_AUDIT_DATA_INIT(&ad, IPC);
4998 	ad.u.ipc_id = shp->shm_perm.key;
4999 
5000 	return avc_has_perm(sid, isec->sid, SECCLASS_SHM,
5001 			    SHM__ASSOCIATE, &ad);
5002 }
5003 
5004 /* Note, at this point, shp is locked down */
5005 static int selinux_shm_shmctl(struct shmid_kernel *shp, int cmd)
5006 {
5007 	int perms;
5008 	int err;
5009 
5010 	switch (cmd) {
5011 	case IPC_INFO:
5012 	case SHM_INFO:
5013 		/* No specific object, just general system-wide information. */
5014 		return task_has_system(current, SYSTEM__IPC_INFO);
5015 	case IPC_STAT:
5016 	case SHM_STAT:
5017 		perms = SHM__GETATTR | SHM__ASSOCIATE;
5018 		break;
5019 	case IPC_SET:
5020 		perms = SHM__SETATTR;
5021 		break;
5022 	case SHM_LOCK:
5023 	case SHM_UNLOCK:
5024 		perms = SHM__LOCK;
5025 		break;
5026 	case IPC_RMID:
5027 		perms = SHM__DESTROY;
5028 		break;
5029 	default:
5030 		return 0;
5031 	}
5032 
5033 	err = ipc_has_perm(&shp->shm_perm, perms);
5034 	return err;
5035 }
5036 
5037 static int selinux_shm_shmat(struct shmid_kernel *shp,
5038 			     char __user *shmaddr, int shmflg)
5039 {
5040 	u32 perms;
5041 
5042 	if (shmflg & SHM_RDONLY)
5043 		perms = SHM__READ;
5044 	else
5045 		perms = SHM__READ | SHM__WRITE;
5046 
5047 	return ipc_has_perm(&shp->shm_perm, perms);
5048 }
5049 
5050 /* Semaphore security operations */
5051 static int selinux_sem_alloc_security(struct sem_array *sma)
5052 {
5053 	struct ipc_security_struct *isec;
5054 	struct common_audit_data ad;
5055 	u32 sid = current_sid();
5056 	int rc;
5057 
5058 	rc = ipc_alloc_security(current, &sma->sem_perm, SECCLASS_SEM);
5059 	if (rc)
5060 		return rc;
5061 
5062 	isec = sma->sem_perm.security;
5063 
5064 	COMMON_AUDIT_DATA_INIT(&ad, IPC);
5065 	ad.u.ipc_id = sma->sem_perm.key;
5066 
5067 	rc = avc_has_perm(sid, isec->sid, SECCLASS_SEM,
5068 			  SEM__CREATE, &ad);
5069 	if (rc) {
5070 		ipc_free_security(&sma->sem_perm);
5071 		return rc;
5072 	}
5073 	return 0;
5074 }
5075 
5076 static void selinux_sem_free_security(struct sem_array *sma)
5077 {
5078 	ipc_free_security(&sma->sem_perm);
5079 }
5080 
5081 static int selinux_sem_associate(struct sem_array *sma, int semflg)
5082 {
5083 	struct ipc_security_struct *isec;
5084 	struct common_audit_data ad;
5085 	u32 sid = current_sid();
5086 
5087 	isec = sma->sem_perm.security;
5088 
5089 	COMMON_AUDIT_DATA_INIT(&ad, IPC);
5090 	ad.u.ipc_id = sma->sem_perm.key;
5091 
5092 	return avc_has_perm(sid, isec->sid, SECCLASS_SEM,
5093 			    SEM__ASSOCIATE, &ad);
5094 }
5095 
5096 /* Note, at this point, sma is locked down */
5097 static int selinux_sem_semctl(struct sem_array *sma, int cmd)
5098 {
5099 	int err;
5100 	u32 perms;
5101 
5102 	switch (cmd) {
5103 	case IPC_INFO:
5104 	case SEM_INFO:
5105 		/* No specific object, just general system-wide information. */
5106 		return task_has_system(current, SYSTEM__IPC_INFO);
5107 	case GETPID:
5108 	case GETNCNT:
5109 	case GETZCNT:
5110 		perms = SEM__GETATTR;
5111 		break;
5112 	case GETVAL:
5113 	case GETALL:
5114 		perms = SEM__READ;
5115 		break;
5116 	case SETVAL:
5117 	case SETALL:
5118 		perms = SEM__WRITE;
5119 		break;
5120 	case IPC_RMID:
5121 		perms = SEM__DESTROY;
5122 		break;
5123 	case IPC_SET:
5124 		perms = SEM__SETATTR;
5125 		break;
5126 	case IPC_STAT:
5127 	case SEM_STAT:
5128 		perms = SEM__GETATTR | SEM__ASSOCIATE;
5129 		break;
5130 	default:
5131 		return 0;
5132 	}
5133 
5134 	err = ipc_has_perm(&sma->sem_perm, perms);
5135 	return err;
5136 }
5137 
5138 static int selinux_sem_semop(struct sem_array *sma,
5139 			     struct sembuf *sops, unsigned nsops, int alter)
5140 {
5141 	u32 perms;
5142 
5143 	if (alter)
5144 		perms = SEM__READ | SEM__WRITE;
5145 	else
5146 		perms = SEM__READ;
5147 
5148 	return ipc_has_perm(&sma->sem_perm, perms);
5149 }
5150 
5151 static int selinux_ipc_permission(struct kern_ipc_perm *ipcp, short flag)
5152 {
5153 	u32 av = 0;
5154 
5155 	av = 0;
5156 	if (flag & S_IRUGO)
5157 		av |= IPC__UNIX_READ;
5158 	if (flag & S_IWUGO)
5159 		av |= IPC__UNIX_WRITE;
5160 
5161 	if (av == 0)
5162 		return 0;
5163 
5164 	return ipc_has_perm(ipcp, av);
5165 }
5166 
5167 static void selinux_ipc_getsecid(struct kern_ipc_perm *ipcp, u32 *secid)
5168 {
5169 	struct ipc_security_struct *isec = ipcp->security;
5170 	*secid = isec->sid;
5171 }
5172 
5173 static void selinux_d_instantiate(struct dentry *dentry, struct inode *inode)
5174 {
5175 	if (inode)
5176 		inode_doinit_with_dentry(inode, dentry);
5177 }
5178 
5179 static int selinux_getprocattr(struct task_struct *p,
5180 			       char *name, char **value)
5181 {
5182 	const struct task_security_struct *__tsec;
5183 	u32 sid;
5184 	int error;
5185 	unsigned len;
5186 
5187 	if (current != p) {
5188 		error = current_has_perm(p, PROCESS__GETATTR);
5189 		if (error)
5190 			return error;
5191 	}
5192 
5193 	rcu_read_lock();
5194 	__tsec = __task_cred(p)->security;
5195 
5196 	if (!strcmp(name, "current"))
5197 		sid = __tsec->sid;
5198 	else if (!strcmp(name, "prev"))
5199 		sid = __tsec->osid;
5200 	else if (!strcmp(name, "exec"))
5201 		sid = __tsec->exec_sid;
5202 	else if (!strcmp(name, "fscreate"))
5203 		sid = __tsec->create_sid;
5204 	else if (!strcmp(name, "keycreate"))
5205 		sid = __tsec->keycreate_sid;
5206 	else if (!strcmp(name, "sockcreate"))
5207 		sid = __tsec->sockcreate_sid;
5208 	else
5209 		goto invalid;
5210 	rcu_read_unlock();
5211 
5212 	if (!sid)
5213 		return 0;
5214 
5215 	error = security_sid_to_context(sid, value, &len);
5216 	if (error)
5217 		return error;
5218 	return len;
5219 
5220 invalid:
5221 	rcu_read_unlock();
5222 	return -EINVAL;
5223 }
5224 
5225 static int selinux_setprocattr(struct task_struct *p,
5226 			       char *name, void *value, size_t size)
5227 {
5228 	struct task_security_struct *tsec;
5229 	struct task_struct *tracer;
5230 	struct cred *new;
5231 	u32 sid = 0, ptsid;
5232 	int error;
5233 	char *str = value;
5234 
5235 	if (current != p) {
5236 		/* SELinux only allows a process to change its own
5237 		   security attributes. */
5238 		return -EACCES;
5239 	}
5240 
5241 	/*
5242 	 * Basic control over ability to set these attributes at all.
5243 	 * current == p, but we'll pass them separately in case the
5244 	 * above restriction is ever removed.
5245 	 */
5246 	if (!strcmp(name, "exec"))
5247 		error = current_has_perm(p, PROCESS__SETEXEC);
5248 	else if (!strcmp(name, "fscreate"))
5249 		error = current_has_perm(p, PROCESS__SETFSCREATE);
5250 	else if (!strcmp(name, "keycreate"))
5251 		error = current_has_perm(p, PROCESS__SETKEYCREATE);
5252 	else if (!strcmp(name, "sockcreate"))
5253 		error = current_has_perm(p, PROCESS__SETSOCKCREATE);
5254 	else if (!strcmp(name, "current"))
5255 		error = current_has_perm(p, PROCESS__SETCURRENT);
5256 	else
5257 		error = -EINVAL;
5258 	if (error)
5259 		return error;
5260 
5261 	/* Obtain a SID for the context, if one was specified. */
5262 	if (size && str[1] && str[1] != '\n') {
5263 		if (str[size-1] == '\n') {
5264 			str[size-1] = 0;
5265 			size--;
5266 		}
5267 		error = security_context_to_sid(value, size, &sid);
5268 		if (error == -EINVAL && !strcmp(name, "fscreate")) {
5269 			if (!capable(CAP_MAC_ADMIN))
5270 				return error;
5271 			error = security_context_to_sid_force(value, size,
5272 							      &sid);
5273 		}
5274 		if (error)
5275 			return error;
5276 	}
5277 
5278 	new = prepare_creds();
5279 	if (!new)
5280 		return -ENOMEM;
5281 
5282 	/* Permission checking based on the specified context is
5283 	   performed during the actual operation (execve,
5284 	   open/mkdir/...), when we know the full context of the
5285 	   operation.  See selinux_bprm_set_creds for the execve
5286 	   checks and may_create for the file creation checks. The
5287 	   operation will then fail if the context is not permitted. */
5288 	tsec = new->security;
5289 	if (!strcmp(name, "exec")) {
5290 		tsec->exec_sid = sid;
5291 	} else if (!strcmp(name, "fscreate")) {
5292 		tsec->create_sid = sid;
5293 	} else if (!strcmp(name, "keycreate")) {
5294 		error = may_create_key(sid, p);
5295 		if (error)
5296 			goto abort_change;
5297 		tsec->keycreate_sid = sid;
5298 	} else if (!strcmp(name, "sockcreate")) {
5299 		tsec->sockcreate_sid = sid;
5300 	} else if (!strcmp(name, "current")) {
5301 		error = -EINVAL;
5302 		if (sid == 0)
5303 			goto abort_change;
5304 
5305 		/* Only allow single threaded processes to change context */
5306 		error = -EPERM;
5307 		if (!current_is_single_threaded()) {
5308 			error = security_bounded_transition(tsec->sid, sid);
5309 			if (error)
5310 				goto abort_change;
5311 		}
5312 
5313 		/* Check permissions for the transition. */
5314 		error = avc_has_perm(tsec->sid, sid, SECCLASS_PROCESS,
5315 				     PROCESS__DYNTRANSITION, NULL);
5316 		if (error)
5317 			goto abort_change;
5318 
5319 		/* Check for ptracing, and update the task SID if ok.
5320 		   Otherwise, leave SID unchanged and fail. */
5321 		ptsid = 0;
5322 		task_lock(p);
5323 		tracer = tracehook_tracer_task(p);
5324 		if (tracer)
5325 			ptsid = task_sid(tracer);
5326 		task_unlock(p);
5327 
5328 		if (tracer) {
5329 			error = avc_has_perm(ptsid, sid, SECCLASS_PROCESS,
5330 					     PROCESS__PTRACE, NULL);
5331 			if (error)
5332 				goto abort_change;
5333 		}
5334 
5335 		tsec->sid = sid;
5336 	} else {
5337 		error = -EINVAL;
5338 		goto abort_change;
5339 	}
5340 
5341 	commit_creds(new);
5342 	return size;
5343 
5344 abort_change:
5345 	abort_creds(new);
5346 	return error;
5347 }
5348 
5349 static int selinux_secid_to_secctx(u32 secid, char **secdata, u32 *seclen)
5350 {
5351 	return security_sid_to_context(secid, secdata, seclen);
5352 }
5353 
5354 static int selinux_secctx_to_secid(const char *secdata, u32 seclen, u32 *secid)
5355 {
5356 	return security_context_to_sid(secdata, seclen, secid);
5357 }
5358 
5359 static void selinux_release_secctx(char *secdata, u32 seclen)
5360 {
5361 	kfree(secdata);
5362 }
5363 
5364 /*
5365  *	called with inode->i_mutex locked
5366  */
5367 static int selinux_inode_notifysecctx(struct inode *inode, void *ctx, u32 ctxlen)
5368 {
5369 	return selinux_inode_setsecurity(inode, XATTR_SELINUX_SUFFIX, ctx, ctxlen, 0);
5370 }
5371 
5372 /*
5373  *	called with inode->i_mutex locked
5374  */
5375 static int selinux_inode_setsecctx(struct dentry *dentry, void *ctx, u32 ctxlen)
5376 {
5377 	return __vfs_setxattr_noperm(dentry, XATTR_NAME_SELINUX, ctx, ctxlen, 0);
5378 }
5379 
5380 static int selinux_inode_getsecctx(struct inode *inode, void **ctx, u32 *ctxlen)
5381 {
5382 	int len = 0;
5383 	len = selinux_inode_getsecurity(inode, XATTR_SELINUX_SUFFIX,
5384 						ctx, true);
5385 	if (len < 0)
5386 		return len;
5387 	*ctxlen = len;
5388 	return 0;
5389 }
5390 #ifdef CONFIG_KEYS
5391 
5392 static int selinux_key_alloc(struct key *k, const struct cred *cred,
5393 			     unsigned long flags)
5394 {
5395 	const struct task_security_struct *tsec;
5396 	struct key_security_struct *ksec;
5397 
5398 	ksec = kzalloc(sizeof(struct key_security_struct), GFP_KERNEL);
5399 	if (!ksec)
5400 		return -ENOMEM;
5401 
5402 	tsec = cred->security;
5403 	if (tsec->keycreate_sid)
5404 		ksec->sid = tsec->keycreate_sid;
5405 	else
5406 		ksec->sid = tsec->sid;
5407 
5408 	k->security = ksec;
5409 	return 0;
5410 }
5411 
5412 static void selinux_key_free(struct key *k)
5413 {
5414 	struct key_security_struct *ksec = k->security;
5415 
5416 	k->security = NULL;
5417 	kfree(ksec);
5418 }
5419 
5420 static int selinux_key_permission(key_ref_t key_ref,
5421 				  const struct cred *cred,
5422 				  key_perm_t perm)
5423 {
5424 	struct key *key;
5425 	struct key_security_struct *ksec;
5426 	u32 sid;
5427 
5428 	/* if no specific permissions are requested, we skip the
5429 	   permission check. No serious, additional covert channels
5430 	   appear to be created. */
5431 	if (perm == 0)
5432 		return 0;
5433 
5434 	sid = cred_sid(cred);
5435 
5436 	key = key_ref_to_ptr(key_ref);
5437 	ksec = key->security;
5438 
5439 	return avc_has_perm(sid, ksec->sid, SECCLASS_KEY, perm, NULL);
5440 }
5441 
5442 static int selinux_key_getsecurity(struct key *key, char **_buffer)
5443 {
5444 	struct key_security_struct *ksec = key->security;
5445 	char *context = NULL;
5446 	unsigned len;
5447 	int rc;
5448 
5449 	rc = security_sid_to_context(ksec->sid, &context, &len);
5450 	if (!rc)
5451 		rc = len;
5452 	*_buffer = context;
5453 	return rc;
5454 }
5455 
5456 #endif
5457 
5458 static struct security_operations selinux_ops = {
5459 	.name =				"selinux",
5460 
5461 	.ptrace_access_check =		selinux_ptrace_access_check,
5462 	.ptrace_traceme =		selinux_ptrace_traceme,
5463 	.capget =			selinux_capget,
5464 	.capset =			selinux_capset,
5465 	.sysctl =			selinux_sysctl,
5466 	.capable =			selinux_capable,
5467 	.quotactl =			selinux_quotactl,
5468 	.quota_on =			selinux_quota_on,
5469 	.syslog =			selinux_syslog,
5470 	.vm_enough_memory =		selinux_vm_enough_memory,
5471 
5472 	.netlink_send =			selinux_netlink_send,
5473 	.netlink_recv =			selinux_netlink_recv,
5474 
5475 	.bprm_set_creds =		selinux_bprm_set_creds,
5476 	.bprm_committing_creds =	selinux_bprm_committing_creds,
5477 	.bprm_committed_creds =		selinux_bprm_committed_creds,
5478 	.bprm_secureexec =		selinux_bprm_secureexec,
5479 
5480 	.sb_alloc_security =		selinux_sb_alloc_security,
5481 	.sb_free_security =		selinux_sb_free_security,
5482 	.sb_copy_data =			selinux_sb_copy_data,
5483 	.sb_kern_mount =		selinux_sb_kern_mount,
5484 	.sb_show_options =		selinux_sb_show_options,
5485 	.sb_statfs =			selinux_sb_statfs,
5486 	.sb_mount =			selinux_mount,
5487 	.sb_umount =			selinux_umount,
5488 	.sb_set_mnt_opts =		selinux_set_mnt_opts,
5489 	.sb_clone_mnt_opts =		selinux_sb_clone_mnt_opts,
5490 	.sb_parse_opts_str = 		selinux_parse_opts_str,
5491 
5492 
5493 	.inode_alloc_security =		selinux_inode_alloc_security,
5494 	.inode_free_security =		selinux_inode_free_security,
5495 	.inode_init_security =		selinux_inode_init_security,
5496 	.inode_create =			selinux_inode_create,
5497 	.inode_link =			selinux_inode_link,
5498 	.inode_unlink =			selinux_inode_unlink,
5499 	.inode_symlink =		selinux_inode_symlink,
5500 	.inode_mkdir =			selinux_inode_mkdir,
5501 	.inode_rmdir =			selinux_inode_rmdir,
5502 	.inode_mknod =			selinux_inode_mknod,
5503 	.inode_rename =			selinux_inode_rename,
5504 	.inode_readlink =		selinux_inode_readlink,
5505 	.inode_follow_link =		selinux_inode_follow_link,
5506 	.inode_permission =		selinux_inode_permission,
5507 	.inode_setattr =		selinux_inode_setattr,
5508 	.inode_getattr =		selinux_inode_getattr,
5509 	.inode_setxattr =		selinux_inode_setxattr,
5510 	.inode_post_setxattr =		selinux_inode_post_setxattr,
5511 	.inode_getxattr =		selinux_inode_getxattr,
5512 	.inode_listxattr =		selinux_inode_listxattr,
5513 	.inode_removexattr =		selinux_inode_removexattr,
5514 	.inode_getsecurity =		selinux_inode_getsecurity,
5515 	.inode_setsecurity =		selinux_inode_setsecurity,
5516 	.inode_listsecurity =		selinux_inode_listsecurity,
5517 	.inode_getsecid =		selinux_inode_getsecid,
5518 
5519 	.file_permission =		selinux_file_permission,
5520 	.file_alloc_security =		selinux_file_alloc_security,
5521 	.file_free_security =		selinux_file_free_security,
5522 	.file_ioctl =			selinux_file_ioctl,
5523 	.file_mmap =			selinux_file_mmap,
5524 	.file_mprotect =		selinux_file_mprotect,
5525 	.file_lock =			selinux_file_lock,
5526 	.file_fcntl =			selinux_file_fcntl,
5527 	.file_set_fowner =		selinux_file_set_fowner,
5528 	.file_send_sigiotask =		selinux_file_send_sigiotask,
5529 	.file_receive =			selinux_file_receive,
5530 
5531 	.dentry_open =			selinux_dentry_open,
5532 
5533 	.task_create =			selinux_task_create,
5534 	.cred_alloc_blank =		selinux_cred_alloc_blank,
5535 	.cred_free =			selinux_cred_free,
5536 	.cred_prepare =			selinux_cred_prepare,
5537 	.cred_transfer =		selinux_cred_transfer,
5538 	.kernel_act_as =		selinux_kernel_act_as,
5539 	.kernel_create_files_as =	selinux_kernel_create_files_as,
5540 	.kernel_module_request =	selinux_kernel_module_request,
5541 	.task_setpgid =			selinux_task_setpgid,
5542 	.task_getpgid =			selinux_task_getpgid,
5543 	.task_getsid =			selinux_task_getsid,
5544 	.task_getsecid =		selinux_task_getsecid,
5545 	.task_setnice =			selinux_task_setnice,
5546 	.task_setioprio =		selinux_task_setioprio,
5547 	.task_getioprio =		selinux_task_getioprio,
5548 	.task_setrlimit =		selinux_task_setrlimit,
5549 	.task_setscheduler =		selinux_task_setscheduler,
5550 	.task_getscheduler =		selinux_task_getscheduler,
5551 	.task_movememory =		selinux_task_movememory,
5552 	.task_kill =			selinux_task_kill,
5553 	.task_wait =			selinux_task_wait,
5554 	.task_to_inode =		selinux_task_to_inode,
5555 
5556 	.ipc_permission =		selinux_ipc_permission,
5557 	.ipc_getsecid =			selinux_ipc_getsecid,
5558 
5559 	.msg_msg_alloc_security =	selinux_msg_msg_alloc_security,
5560 	.msg_msg_free_security =	selinux_msg_msg_free_security,
5561 
5562 	.msg_queue_alloc_security =	selinux_msg_queue_alloc_security,
5563 	.msg_queue_free_security =	selinux_msg_queue_free_security,
5564 	.msg_queue_associate =		selinux_msg_queue_associate,
5565 	.msg_queue_msgctl =		selinux_msg_queue_msgctl,
5566 	.msg_queue_msgsnd =		selinux_msg_queue_msgsnd,
5567 	.msg_queue_msgrcv =		selinux_msg_queue_msgrcv,
5568 
5569 	.shm_alloc_security =		selinux_shm_alloc_security,
5570 	.shm_free_security =		selinux_shm_free_security,
5571 	.shm_associate =		selinux_shm_associate,
5572 	.shm_shmctl =			selinux_shm_shmctl,
5573 	.shm_shmat =			selinux_shm_shmat,
5574 
5575 	.sem_alloc_security =		selinux_sem_alloc_security,
5576 	.sem_free_security =		selinux_sem_free_security,
5577 	.sem_associate =		selinux_sem_associate,
5578 	.sem_semctl =			selinux_sem_semctl,
5579 	.sem_semop =			selinux_sem_semop,
5580 
5581 	.d_instantiate =		selinux_d_instantiate,
5582 
5583 	.getprocattr =			selinux_getprocattr,
5584 	.setprocattr =			selinux_setprocattr,
5585 
5586 	.secid_to_secctx =		selinux_secid_to_secctx,
5587 	.secctx_to_secid =		selinux_secctx_to_secid,
5588 	.release_secctx =		selinux_release_secctx,
5589 	.inode_notifysecctx =		selinux_inode_notifysecctx,
5590 	.inode_setsecctx =		selinux_inode_setsecctx,
5591 	.inode_getsecctx =		selinux_inode_getsecctx,
5592 
5593 	.unix_stream_connect =		selinux_socket_unix_stream_connect,
5594 	.unix_may_send =		selinux_socket_unix_may_send,
5595 
5596 	.socket_create =		selinux_socket_create,
5597 	.socket_post_create =		selinux_socket_post_create,
5598 	.socket_bind =			selinux_socket_bind,
5599 	.socket_connect =		selinux_socket_connect,
5600 	.socket_listen =		selinux_socket_listen,
5601 	.socket_accept =		selinux_socket_accept,
5602 	.socket_sendmsg =		selinux_socket_sendmsg,
5603 	.socket_recvmsg =		selinux_socket_recvmsg,
5604 	.socket_getsockname =		selinux_socket_getsockname,
5605 	.socket_getpeername =		selinux_socket_getpeername,
5606 	.socket_getsockopt =		selinux_socket_getsockopt,
5607 	.socket_setsockopt =		selinux_socket_setsockopt,
5608 	.socket_shutdown =		selinux_socket_shutdown,
5609 	.socket_sock_rcv_skb =		selinux_socket_sock_rcv_skb,
5610 	.socket_getpeersec_stream =	selinux_socket_getpeersec_stream,
5611 	.socket_getpeersec_dgram =	selinux_socket_getpeersec_dgram,
5612 	.sk_alloc_security =		selinux_sk_alloc_security,
5613 	.sk_free_security =		selinux_sk_free_security,
5614 	.sk_clone_security =		selinux_sk_clone_security,
5615 	.sk_getsecid =			selinux_sk_getsecid,
5616 	.sock_graft =			selinux_sock_graft,
5617 	.inet_conn_request =		selinux_inet_conn_request,
5618 	.inet_csk_clone =		selinux_inet_csk_clone,
5619 	.inet_conn_established =	selinux_inet_conn_established,
5620 	.req_classify_flow =		selinux_req_classify_flow,
5621 	.tun_dev_create =		selinux_tun_dev_create,
5622 	.tun_dev_post_create = 		selinux_tun_dev_post_create,
5623 	.tun_dev_attach =		selinux_tun_dev_attach,
5624 
5625 #ifdef CONFIG_SECURITY_NETWORK_XFRM
5626 	.xfrm_policy_alloc_security =	selinux_xfrm_policy_alloc,
5627 	.xfrm_policy_clone_security =	selinux_xfrm_policy_clone,
5628 	.xfrm_policy_free_security =	selinux_xfrm_policy_free,
5629 	.xfrm_policy_delete_security =	selinux_xfrm_policy_delete,
5630 	.xfrm_state_alloc_security =	selinux_xfrm_state_alloc,
5631 	.xfrm_state_free_security =	selinux_xfrm_state_free,
5632 	.xfrm_state_delete_security =	selinux_xfrm_state_delete,
5633 	.xfrm_policy_lookup =		selinux_xfrm_policy_lookup,
5634 	.xfrm_state_pol_flow_match =	selinux_xfrm_state_pol_flow_match,
5635 	.xfrm_decode_session =		selinux_xfrm_decode_session,
5636 #endif
5637 
5638 #ifdef CONFIG_KEYS
5639 	.key_alloc =			selinux_key_alloc,
5640 	.key_free =			selinux_key_free,
5641 	.key_permission =		selinux_key_permission,
5642 	.key_getsecurity =		selinux_key_getsecurity,
5643 #endif
5644 
5645 #ifdef CONFIG_AUDIT
5646 	.audit_rule_init =		selinux_audit_rule_init,
5647 	.audit_rule_known =		selinux_audit_rule_known,
5648 	.audit_rule_match =		selinux_audit_rule_match,
5649 	.audit_rule_free =		selinux_audit_rule_free,
5650 #endif
5651 };
5652 
5653 static __init int selinux_init(void)
5654 {
5655 	if (!security_module_enable(&selinux_ops)) {
5656 		selinux_enabled = 0;
5657 		return 0;
5658 	}
5659 
5660 	if (!selinux_enabled) {
5661 		printk(KERN_INFO "SELinux:  Disabled at boot.\n");
5662 		return 0;
5663 	}
5664 
5665 	printk(KERN_INFO "SELinux:  Initializing.\n");
5666 
5667 	/* Set the security state for the initial task. */
5668 	cred_init_security();
5669 
5670 	sel_inode_cache = kmem_cache_create("selinux_inode_security",
5671 					    sizeof(struct inode_security_struct),
5672 					    0, SLAB_PANIC, NULL);
5673 	avc_init();
5674 
5675 	secondary_ops = security_ops;
5676 	if (!secondary_ops)
5677 		panic("SELinux: No initial security operations\n");
5678 	if (register_security(&selinux_ops))
5679 		panic("SELinux: Unable to register with kernel.\n");
5680 
5681 	if (selinux_enforcing)
5682 		printk(KERN_DEBUG "SELinux:  Starting in enforcing mode\n");
5683 	else
5684 		printk(KERN_DEBUG "SELinux:  Starting in permissive mode\n");
5685 
5686 	return 0;
5687 }
5688 
5689 void selinux_complete_init(void)
5690 {
5691 	printk(KERN_DEBUG "SELinux:  Completing initialization.\n");
5692 
5693 	/* Set up any superblocks initialized prior to the policy load. */
5694 	printk(KERN_DEBUG "SELinux:  Setting up existing superblocks.\n");
5695 	spin_lock(&sb_lock);
5696 	spin_lock(&sb_security_lock);
5697 next_sb:
5698 	if (!list_empty(&superblock_security_head)) {
5699 		struct superblock_security_struct *sbsec =
5700 				list_entry(superblock_security_head.next,
5701 					   struct superblock_security_struct,
5702 					   list);
5703 		struct super_block *sb = sbsec->sb;
5704 		sb->s_count++;
5705 		spin_unlock(&sb_security_lock);
5706 		spin_unlock(&sb_lock);
5707 		down_read(&sb->s_umount);
5708 		if (sb->s_root)
5709 			superblock_doinit(sb, NULL);
5710 		drop_super(sb);
5711 		spin_lock(&sb_lock);
5712 		spin_lock(&sb_security_lock);
5713 		list_del_init(&sbsec->list);
5714 		goto next_sb;
5715 	}
5716 	spin_unlock(&sb_security_lock);
5717 	spin_unlock(&sb_lock);
5718 }
5719 
5720 /* SELinux requires early initialization in order to label
5721    all processes and objects when they are created. */
5722 security_initcall(selinux_init);
5723 
5724 #if defined(CONFIG_NETFILTER)
5725 
5726 static struct nf_hook_ops selinux_ipv4_ops[] = {
5727 	{
5728 		.hook =		selinux_ipv4_postroute,
5729 		.owner =	THIS_MODULE,
5730 		.pf =		PF_INET,
5731 		.hooknum =	NF_INET_POST_ROUTING,
5732 		.priority =	NF_IP_PRI_SELINUX_LAST,
5733 	},
5734 	{
5735 		.hook =		selinux_ipv4_forward,
5736 		.owner =	THIS_MODULE,
5737 		.pf =		PF_INET,
5738 		.hooknum =	NF_INET_FORWARD,
5739 		.priority =	NF_IP_PRI_SELINUX_FIRST,
5740 	},
5741 	{
5742 		.hook =		selinux_ipv4_output,
5743 		.owner =	THIS_MODULE,
5744 		.pf =		PF_INET,
5745 		.hooknum =	NF_INET_LOCAL_OUT,
5746 		.priority =	NF_IP_PRI_SELINUX_FIRST,
5747 	}
5748 };
5749 
5750 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
5751 
5752 static struct nf_hook_ops selinux_ipv6_ops[] = {
5753 	{
5754 		.hook =		selinux_ipv6_postroute,
5755 		.owner =	THIS_MODULE,
5756 		.pf =		PF_INET6,
5757 		.hooknum =	NF_INET_POST_ROUTING,
5758 		.priority =	NF_IP6_PRI_SELINUX_LAST,
5759 	},
5760 	{
5761 		.hook =		selinux_ipv6_forward,
5762 		.owner =	THIS_MODULE,
5763 		.pf =		PF_INET6,
5764 		.hooknum =	NF_INET_FORWARD,
5765 		.priority =	NF_IP6_PRI_SELINUX_FIRST,
5766 	}
5767 };
5768 
5769 #endif	/* IPV6 */
5770 
5771 static int __init selinux_nf_ip_init(void)
5772 {
5773 	int err = 0;
5774 
5775 	if (!selinux_enabled)
5776 		goto out;
5777 
5778 	printk(KERN_DEBUG "SELinux:  Registering netfilter hooks\n");
5779 
5780 	err = nf_register_hooks(selinux_ipv4_ops, ARRAY_SIZE(selinux_ipv4_ops));
5781 	if (err)
5782 		panic("SELinux: nf_register_hooks for IPv4: error %d\n", err);
5783 
5784 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
5785 	err = nf_register_hooks(selinux_ipv6_ops, ARRAY_SIZE(selinux_ipv6_ops));
5786 	if (err)
5787 		panic("SELinux: nf_register_hooks for IPv6: error %d\n", err);
5788 #endif	/* IPV6 */
5789 
5790 out:
5791 	return err;
5792 }
5793 
5794 __initcall(selinux_nf_ip_init);
5795 
5796 #ifdef CONFIG_SECURITY_SELINUX_DISABLE
5797 static void selinux_nf_ip_exit(void)
5798 {
5799 	printk(KERN_DEBUG "SELinux:  Unregistering netfilter hooks\n");
5800 
5801 	nf_unregister_hooks(selinux_ipv4_ops, ARRAY_SIZE(selinux_ipv4_ops));
5802 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
5803 	nf_unregister_hooks(selinux_ipv6_ops, ARRAY_SIZE(selinux_ipv6_ops));
5804 #endif	/* IPV6 */
5805 }
5806 #endif
5807 
5808 #else /* CONFIG_NETFILTER */
5809 
5810 #ifdef CONFIG_SECURITY_SELINUX_DISABLE
5811 #define selinux_nf_ip_exit()
5812 #endif
5813 
5814 #endif /* CONFIG_NETFILTER */
5815 
5816 #ifdef CONFIG_SECURITY_SELINUX_DISABLE
5817 static int selinux_disabled;
5818 
5819 int selinux_disable(void)
5820 {
5821 	extern void exit_sel_fs(void);
5822 
5823 	if (ss_initialized) {
5824 		/* Not permitted after initial policy load. */
5825 		return -EINVAL;
5826 	}
5827 
5828 	if (selinux_disabled) {
5829 		/* Only do this once. */
5830 		return -EINVAL;
5831 	}
5832 
5833 	printk(KERN_INFO "SELinux:  Disabled at runtime.\n");
5834 
5835 	selinux_disabled = 1;
5836 	selinux_enabled = 0;
5837 
5838 	/* Reset security_ops to the secondary module, dummy or capability. */
5839 	security_ops = secondary_ops;
5840 
5841 	/* Try to destroy the avc node cache */
5842 	avc_disable();
5843 
5844 	/* Unregister netfilter hooks. */
5845 	selinux_nf_ip_exit();
5846 
5847 	/* Unregister selinuxfs. */
5848 	exit_sel_fs();
5849 
5850 	return 0;
5851 }
5852 #endif
5853