xref: /openbmc/linux/security/selinux/hooks.c (revision 3d5271f9883cba7b54762bc4fe027d4172f06db7)
1 /*
2  *  NSA Security-Enhanced Linux (SELinux) security module
3  *
4  *  This file contains the SELinux hook function implementations.
5  *
6  *  Authors:  Stephen Smalley, <sds@epoch.ncsc.mil>
7  *            Chris Vance, <cvance@nai.com>
8  *            Wayne Salamon, <wsalamon@nai.com>
9  *            James Morris <jmorris@redhat.com>
10  *
11  *  Copyright (C) 2001,2002 Networks Associates Technology, Inc.
12  *  Copyright (C) 2003 Red Hat, Inc., James Morris <jmorris@redhat.com>
13  *  Copyright (C) 2004-2005 Trusted Computer Solutions, Inc.
14  *                          <dgoeddel@trustedcs.com>
15  *
16  *	This program is free software; you can redistribute it and/or modify
17  *	it under the terms of the GNU General Public License version 2,
18  *      as published by the Free Software Foundation.
19  */
20 
21 #include <linux/config.h>
22 #include <linux/module.h>
23 #include <linux/init.h>
24 #include <linux/kernel.h>
25 #include <linux/ptrace.h>
26 #include <linux/errno.h>
27 #include <linux/sched.h>
28 #include <linux/security.h>
29 #include <linux/xattr.h>
30 #include <linux/capability.h>
31 #include <linux/unistd.h>
32 #include <linux/mm.h>
33 #include <linux/mman.h>
34 #include <linux/slab.h>
35 #include <linux/pagemap.h>
36 #include <linux/swap.h>
37 #include <linux/smp_lock.h>
38 #include <linux/spinlock.h>
39 #include <linux/syscalls.h>
40 #include <linux/file.h>
41 #include <linux/namei.h>
42 #include <linux/mount.h>
43 #include <linux/ext2_fs.h>
44 #include <linux/proc_fs.h>
45 #include <linux/kd.h>
46 #include <linux/netfilter_ipv4.h>
47 #include <linux/netfilter_ipv6.h>
48 #include <linux/tty.h>
49 #include <net/icmp.h>
50 #include <net/ip.h>		/* for sysctl_local_port_range[] */
51 #include <net/tcp.h>		/* struct or_callable used in sock_rcv_skb */
52 #include <asm/uaccess.h>
53 #include <asm/semaphore.h>
54 #include <asm/ioctls.h>
55 #include <linux/bitops.h>
56 #include <linux/interrupt.h>
57 #include <linux/netdevice.h>	/* for network interface checks */
58 #include <linux/netlink.h>
59 #include <linux/tcp.h>
60 #include <linux/udp.h>
61 #include <linux/quota.h>
62 #include <linux/un.h>		/* for Unix socket types */
63 #include <net/af_unix.h>	/* for Unix socket types */
64 #include <linux/parser.h>
65 #include <linux/nfs_mount.h>
66 #include <net/ipv6.h>
67 #include <linux/hugetlb.h>
68 #include <linux/personality.h>
69 #include <linux/sysctl.h>
70 #include <linux/audit.h>
71 #include <linux/string.h>
72 
73 #include "avc.h"
74 #include "objsec.h"
75 #include "netif.h"
76 
77 #define XATTR_SELINUX_SUFFIX "selinux"
78 #define XATTR_NAME_SELINUX XATTR_SECURITY_PREFIX XATTR_SELINUX_SUFFIX
79 
80 extern unsigned int policydb_loaded_version;
81 extern int selinux_nlmsg_lookup(u16 sclass, u16 nlmsg_type, u32 *perm);
82 
83 #ifdef CONFIG_SECURITY_SELINUX_DEVELOP
84 int selinux_enforcing = 0;
85 
86 static int __init enforcing_setup(char *str)
87 {
88 	selinux_enforcing = simple_strtol(str,NULL,0);
89 	return 1;
90 }
91 __setup("enforcing=", enforcing_setup);
92 #endif
93 
94 #ifdef CONFIG_SECURITY_SELINUX_BOOTPARAM
95 int selinux_enabled = CONFIG_SECURITY_SELINUX_BOOTPARAM_VALUE;
96 
97 static int __init selinux_enabled_setup(char *str)
98 {
99 	selinux_enabled = simple_strtol(str, NULL, 0);
100 	return 1;
101 }
102 __setup("selinux=", selinux_enabled_setup);
103 #endif
104 
105 /* Original (dummy) security module. */
106 static struct security_operations *original_ops = NULL;
107 
108 /* Minimal support for a secondary security module,
109    just to allow the use of the dummy or capability modules.
110    The owlsm module can alternatively be used as a secondary
111    module as long as CONFIG_OWLSM_FD is not enabled. */
112 static struct security_operations *secondary_ops = NULL;
113 
114 /* Lists of inode and superblock security structures initialized
115    before the policy was loaded. */
116 static LIST_HEAD(superblock_security_head);
117 static DEFINE_SPINLOCK(sb_security_lock);
118 
119 /* Allocate and free functions for each kind of security blob. */
120 
121 static int task_alloc_security(struct task_struct *task)
122 {
123 	struct task_security_struct *tsec;
124 
125 	tsec = kzalloc(sizeof(struct task_security_struct), GFP_KERNEL);
126 	if (!tsec)
127 		return -ENOMEM;
128 
129 	tsec->magic = SELINUX_MAGIC;
130 	tsec->task = task;
131 	tsec->osid = tsec->sid = tsec->ptrace_sid = SECINITSID_UNLABELED;
132 	task->security = tsec;
133 
134 	return 0;
135 }
136 
137 static void task_free_security(struct task_struct *task)
138 {
139 	struct task_security_struct *tsec = task->security;
140 
141 	if (!tsec || tsec->magic != SELINUX_MAGIC)
142 		return;
143 
144 	task->security = NULL;
145 	kfree(tsec);
146 }
147 
148 static int inode_alloc_security(struct inode *inode)
149 {
150 	struct task_security_struct *tsec = current->security;
151 	struct inode_security_struct *isec;
152 
153 	isec = kzalloc(sizeof(struct inode_security_struct), GFP_KERNEL);
154 	if (!isec)
155 		return -ENOMEM;
156 
157 	init_MUTEX(&isec->sem);
158 	INIT_LIST_HEAD(&isec->list);
159 	isec->magic = SELINUX_MAGIC;
160 	isec->inode = inode;
161 	isec->sid = SECINITSID_UNLABELED;
162 	isec->sclass = SECCLASS_FILE;
163 	if (tsec && tsec->magic == SELINUX_MAGIC)
164 		isec->task_sid = tsec->sid;
165 	else
166 		isec->task_sid = SECINITSID_UNLABELED;
167 	inode->i_security = isec;
168 
169 	return 0;
170 }
171 
172 static void inode_free_security(struct inode *inode)
173 {
174 	struct inode_security_struct *isec = inode->i_security;
175 	struct superblock_security_struct *sbsec = inode->i_sb->s_security;
176 
177 	if (!isec || isec->magic != SELINUX_MAGIC)
178 		return;
179 
180 	spin_lock(&sbsec->isec_lock);
181 	if (!list_empty(&isec->list))
182 		list_del_init(&isec->list);
183 	spin_unlock(&sbsec->isec_lock);
184 
185 	inode->i_security = NULL;
186 	kfree(isec);
187 }
188 
189 static int file_alloc_security(struct file *file)
190 {
191 	struct task_security_struct *tsec = current->security;
192 	struct file_security_struct *fsec;
193 
194 	fsec = kzalloc(sizeof(struct file_security_struct), GFP_ATOMIC);
195 	if (!fsec)
196 		return -ENOMEM;
197 
198 	fsec->magic = SELINUX_MAGIC;
199 	fsec->file = file;
200 	if (tsec && tsec->magic == SELINUX_MAGIC) {
201 		fsec->sid = tsec->sid;
202 		fsec->fown_sid = tsec->sid;
203 	} else {
204 		fsec->sid = SECINITSID_UNLABELED;
205 		fsec->fown_sid = SECINITSID_UNLABELED;
206 	}
207 	file->f_security = fsec;
208 
209 	return 0;
210 }
211 
212 static void file_free_security(struct file *file)
213 {
214 	struct file_security_struct *fsec = file->f_security;
215 
216 	if (!fsec || fsec->magic != SELINUX_MAGIC)
217 		return;
218 
219 	file->f_security = NULL;
220 	kfree(fsec);
221 }
222 
223 static int superblock_alloc_security(struct super_block *sb)
224 {
225 	struct superblock_security_struct *sbsec;
226 
227 	sbsec = kzalloc(sizeof(struct superblock_security_struct), GFP_KERNEL);
228 	if (!sbsec)
229 		return -ENOMEM;
230 
231 	init_MUTEX(&sbsec->sem);
232 	INIT_LIST_HEAD(&sbsec->list);
233 	INIT_LIST_HEAD(&sbsec->isec_head);
234 	spin_lock_init(&sbsec->isec_lock);
235 	sbsec->magic = SELINUX_MAGIC;
236 	sbsec->sb = sb;
237 	sbsec->sid = SECINITSID_UNLABELED;
238 	sbsec->def_sid = SECINITSID_FILE;
239 	sb->s_security = sbsec;
240 
241 	return 0;
242 }
243 
244 static void superblock_free_security(struct super_block *sb)
245 {
246 	struct superblock_security_struct *sbsec = sb->s_security;
247 
248 	if (!sbsec || sbsec->magic != SELINUX_MAGIC)
249 		return;
250 
251 	spin_lock(&sb_security_lock);
252 	if (!list_empty(&sbsec->list))
253 		list_del_init(&sbsec->list);
254 	spin_unlock(&sb_security_lock);
255 
256 	sb->s_security = NULL;
257 	kfree(sbsec);
258 }
259 
260 #ifdef CONFIG_SECURITY_NETWORK
261 static int sk_alloc_security(struct sock *sk, int family, gfp_t priority)
262 {
263 	struct sk_security_struct *ssec;
264 
265 	if (family != PF_UNIX)
266 		return 0;
267 
268 	ssec = kzalloc(sizeof(*ssec), priority);
269 	if (!ssec)
270 		return -ENOMEM;
271 
272 	ssec->magic = SELINUX_MAGIC;
273 	ssec->sk = sk;
274 	ssec->peer_sid = SECINITSID_UNLABELED;
275 	sk->sk_security = ssec;
276 
277 	return 0;
278 }
279 
280 static void sk_free_security(struct sock *sk)
281 {
282 	struct sk_security_struct *ssec = sk->sk_security;
283 
284 	if (sk->sk_family != PF_UNIX || ssec->magic != SELINUX_MAGIC)
285 		return;
286 
287 	sk->sk_security = NULL;
288 	kfree(ssec);
289 }
290 #endif	/* CONFIG_SECURITY_NETWORK */
291 
292 /* The security server must be initialized before
293    any labeling or access decisions can be provided. */
294 extern int ss_initialized;
295 
296 /* The file system's label must be initialized prior to use. */
297 
298 static char *labeling_behaviors[6] = {
299 	"uses xattr",
300 	"uses transition SIDs",
301 	"uses task SIDs",
302 	"uses genfs_contexts",
303 	"not configured for labeling",
304 	"uses mountpoint labeling",
305 };
306 
307 static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dentry);
308 
309 static inline int inode_doinit(struct inode *inode)
310 {
311 	return inode_doinit_with_dentry(inode, NULL);
312 }
313 
314 enum {
315 	Opt_context = 1,
316 	Opt_fscontext = 2,
317 	Opt_defcontext = 4,
318 };
319 
320 static match_table_t tokens = {
321 	{Opt_context, "context=%s"},
322 	{Opt_fscontext, "fscontext=%s"},
323 	{Opt_defcontext, "defcontext=%s"},
324 };
325 
326 #define SEL_MOUNT_FAIL_MSG "SELinux:  duplicate or incompatible mount options\n"
327 
328 static int try_context_mount(struct super_block *sb, void *data)
329 {
330 	char *context = NULL, *defcontext = NULL;
331 	const char *name;
332 	u32 sid;
333 	int alloc = 0, rc = 0, seen = 0;
334 	struct task_security_struct *tsec = current->security;
335 	struct superblock_security_struct *sbsec = sb->s_security;
336 
337 	if (!data)
338 		goto out;
339 
340 	name = sb->s_type->name;
341 
342 	if (sb->s_type->fs_flags & FS_BINARY_MOUNTDATA) {
343 
344 		/* NFS we understand. */
345 		if (!strcmp(name, "nfs")) {
346 			struct nfs_mount_data *d = data;
347 
348 			if (d->version <  NFS_MOUNT_VERSION)
349 				goto out;
350 
351 			if (d->context[0]) {
352 				context = d->context;
353 				seen |= Opt_context;
354 			}
355 		} else
356 			goto out;
357 
358 	} else {
359 		/* Standard string-based options. */
360 		char *p, *options = data;
361 
362 		while ((p = strsep(&options, ",")) != NULL) {
363 			int token;
364 			substring_t args[MAX_OPT_ARGS];
365 
366 			if (!*p)
367 				continue;
368 
369 			token = match_token(p, tokens, args);
370 
371 			switch (token) {
372 			case Opt_context:
373 				if (seen) {
374 					rc = -EINVAL;
375 					printk(KERN_WARNING SEL_MOUNT_FAIL_MSG);
376 					goto out_free;
377 				}
378 				context = match_strdup(&args[0]);
379 				if (!context) {
380 					rc = -ENOMEM;
381 					goto out_free;
382 				}
383 				if (!alloc)
384 					alloc = 1;
385 				seen |= Opt_context;
386 				break;
387 
388 			case Opt_fscontext:
389 				if (seen & (Opt_context|Opt_fscontext)) {
390 					rc = -EINVAL;
391 					printk(KERN_WARNING SEL_MOUNT_FAIL_MSG);
392 					goto out_free;
393 				}
394 				context = match_strdup(&args[0]);
395 				if (!context) {
396 					rc = -ENOMEM;
397 					goto out_free;
398 				}
399 				if (!alloc)
400 					alloc = 1;
401 				seen |= Opt_fscontext;
402 				break;
403 
404 			case Opt_defcontext:
405 				if (sbsec->behavior != SECURITY_FS_USE_XATTR) {
406 					rc = -EINVAL;
407 					printk(KERN_WARNING "SELinux:  "
408 					       "defcontext option is invalid "
409 					       "for this filesystem type\n");
410 					goto out_free;
411 				}
412 				if (seen & (Opt_context|Opt_defcontext)) {
413 					rc = -EINVAL;
414 					printk(KERN_WARNING SEL_MOUNT_FAIL_MSG);
415 					goto out_free;
416 				}
417 				defcontext = match_strdup(&args[0]);
418 				if (!defcontext) {
419 					rc = -ENOMEM;
420 					goto out_free;
421 				}
422 				if (!alloc)
423 					alloc = 1;
424 				seen |= Opt_defcontext;
425 				break;
426 
427 			default:
428 				rc = -EINVAL;
429 				printk(KERN_WARNING "SELinux:  unknown mount "
430 				       "option\n");
431 				goto out_free;
432 
433 			}
434 		}
435 	}
436 
437 	if (!seen)
438 		goto out;
439 
440 	if (context) {
441 		rc = security_context_to_sid(context, strlen(context), &sid);
442 		if (rc) {
443 			printk(KERN_WARNING "SELinux: security_context_to_sid"
444 			       "(%s) failed for (dev %s, type %s) errno=%d\n",
445 			       context, sb->s_id, name, rc);
446 			goto out_free;
447 		}
448 
449 		rc = avc_has_perm(tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM,
450 		                  FILESYSTEM__RELABELFROM, NULL);
451 		if (rc)
452 			goto out_free;
453 
454 		rc = avc_has_perm(tsec->sid, sid, SECCLASS_FILESYSTEM,
455 		                  FILESYSTEM__RELABELTO, NULL);
456 		if (rc)
457 			goto out_free;
458 
459 		sbsec->sid = sid;
460 
461 		if (seen & Opt_context)
462 			sbsec->behavior = SECURITY_FS_USE_MNTPOINT;
463 	}
464 
465 	if (defcontext) {
466 		rc = security_context_to_sid(defcontext, strlen(defcontext), &sid);
467 		if (rc) {
468 			printk(KERN_WARNING "SELinux: security_context_to_sid"
469 			       "(%s) failed for (dev %s, type %s) errno=%d\n",
470 			       defcontext, sb->s_id, name, rc);
471 			goto out_free;
472 		}
473 
474 		if (sid == sbsec->def_sid)
475 			goto out_free;
476 
477 		rc = avc_has_perm(tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM,
478 				  FILESYSTEM__RELABELFROM, NULL);
479 		if (rc)
480 			goto out_free;
481 
482 		rc = avc_has_perm(sid, sbsec->sid, SECCLASS_FILESYSTEM,
483 				  FILESYSTEM__ASSOCIATE, NULL);
484 		if (rc)
485 			goto out_free;
486 
487 		sbsec->def_sid = sid;
488 	}
489 
490 out_free:
491 	if (alloc) {
492 		kfree(context);
493 		kfree(defcontext);
494 	}
495 out:
496 	return rc;
497 }
498 
499 static int superblock_doinit(struct super_block *sb, void *data)
500 {
501 	struct superblock_security_struct *sbsec = sb->s_security;
502 	struct dentry *root = sb->s_root;
503 	struct inode *inode = root->d_inode;
504 	int rc = 0;
505 
506 	down(&sbsec->sem);
507 	if (sbsec->initialized)
508 		goto out;
509 
510 	if (!ss_initialized) {
511 		/* Defer initialization until selinux_complete_init,
512 		   after the initial policy is loaded and the security
513 		   server is ready to handle calls. */
514 		spin_lock(&sb_security_lock);
515 		if (list_empty(&sbsec->list))
516 			list_add(&sbsec->list, &superblock_security_head);
517 		spin_unlock(&sb_security_lock);
518 		goto out;
519 	}
520 
521 	/* Determine the labeling behavior to use for this filesystem type. */
522 	rc = security_fs_use(sb->s_type->name, &sbsec->behavior, &sbsec->sid);
523 	if (rc) {
524 		printk(KERN_WARNING "%s:  security_fs_use(%s) returned %d\n",
525 		       __FUNCTION__, sb->s_type->name, rc);
526 		goto out;
527 	}
528 
529 	rc = try_context_mount(sb, data);
530 	if (rc)
531 		goto out;
532 
533 	if (sbsec->behavior == SECURITY_FS_USE_XATTR) {
534 		/* Make sure that the xattr handler exists and that no
535 		   error other than -ENODATA is returned by getxattr on
536 		   the root directory.  -ENODATA is ok, as this may be
537 		   the first boot of the SELinux kernel before we have
538 		   assigned xattr values to the filesystem. */
539 		if (!inode->i_op->getxattr) {
540 			printk(KERN_WARNING "SELinux: (dev %s, type %s) has no "
541 			       "xattr support\n", sb->s_id, sb->s_type->name);
542 			rc = -EOPNOTSUPP;
543 			goto out;
544 		}
545 		rc = inode->i_op->getxattr(root, XATTR_NAME_SELINUX, NULL, 0);
546 		if (rc < 0 && rc != -ENODATA) {
547 			if (rc == -EOPNOTSUPP)
548 				printk(KERN_WARNING "SELinux: (dev %s, type "
549 				       "%s) has no security xattr handler\n",
550 				       sb->s_id, sb->s_type->name);
551 			else
552 				printk(KERN_WARNING "SELinux: (dev %s, type "
553 				       "%s) getxattr errno %d\n", sb->s_id,
554 				       sb->s_type->name, -rc);
555 			goto out;
556 		}
557 	}
558 
559 	if (strcmp(sb->s_type->name, "proc") == 0)
560 		sbsec->proc = 1;
561 
562 	sbsec->initialized = 1;
563 
564 	if (sbsec->behavior > ARRAY_SIZE(labeling_behaviors)) {
565 		printk(KERN_INFO "SELinux: initialized (dev %s, type %s), unknown behavior\n",
566 		       sb->s_id, sb->s_type->name);
567 	}
568 	else {
569 		printk(KERN_INFO "SELinux: initialized (dev %s, type %s), %s\n",
570 		       sb->s_id, sb->s_type->name,
571 		       labeling_behaviors[sbsec->behavior-1]);
572 	}
573 
574 	/* Initialize the root inode. */
575 	rc = inode_doinit_with_dentry(sb->s_root->d_inode, sb->s_root);
576 
577 	/* Initialize any other inodes associated with the superblock, e.g.
578 	   inodes created prior to initial policy load or inodes created
579 	   during get_sb by a pseudo filesystem that directly
580 	   populates itself. */
581 	spin_lock(&sbsec->isec_lock);
582 next_inode:
583 	if (!list_empty(&sbsec->isec_head)) {
584 		struct inode_security_struct *isec =
585 				list_entry(sbsec->isec_head.next,
586 				           struct inode_security_struct, list);
587 		struct inode *inode = isec->inode;
588 		spin_unlock(&sbsec->isec_lock);
589 		inode = igrab(inode);
590 		if (inode) {
591 			if (!IS_PRIVATE (inode))
592 				inode_doinit(inode);
593 			iput(inode);
594 		}
595 		spin_lock(&sbsec->isec_lock);
596 		list_del_init(&isec->list);
597 		goto next_inode;
598 	}
599 	spin_unlock(&sbsec->isec_lock);
600 out:
601 	up(&sbsec->sem);
602 	return rc;
603 }
604 
605 static inline u16 inode_mode_to_security_class(umode_t mode)
606 {
607 	switch (mode & S_IFMT) {
608 	case S_IFSOCK:
609 		return SECCLASS_SOCK_FILE;
610 	case S_IFLNK:
611 		return SECCLASS_LNK_FILE;
612 	case S_IFREG:
613 		return SECCLASS_FILE;
614 	case S_IFBLK:
615 		return SECCLASS_BLK_FILE;
616 	case S_IFDIR:
617 		return SECCLASS_DIR;
618 	case S_IFCHR:
619 		return SECCLASS_CHR_FILE;
620 	case S_IFIFO:
621 		return SECCLASS_FIFO_FILE;
622 
623 	}
624 
625 	return SECCLASS_FILE;
626 }
627 
628 static inline int default_protocol_stream(int protocol)
629 {
630 	return (protocol == IPPROTO_IP || protocol == IPPROTO_TCP);
631 }
632 
633 static inline int default_protocol_dgram(int protocol)
634 {
635 	return (protocol == IPPROTO_IP || protocol == IPPROTO_UDP);
636 }
637 
638 static inline u16 socket_type_to_security_class(int family, int type, int protocol)
639 {
640 	switch (family) {
641 	case PF_UNIX:
642 		switch (type) {
643 		case SOCK_STREAM:
644 		case SOCK_SEQPACKET:
645 			return SECCLASS_UNIX_STREAM_SOCKET;
646 		case SOCK_DGRAM:
647 			return SECCLASS_UNIX_DGRAM_SOCKET;
648 		}
649 		break;
650 	case PF_INET:
651 	case PF_INET6:
652 		switch (type) {
653 		case SOCK_STREAM:
654 			if (default_protocol_stream(protocol))
655 				return SECCLASS_TCP_SOCKET;
656 			else
657 				return SECCLASS_RAWIP_SOCKET;
658 		case SOCK_DGRAM:
659 			if (default_protocol_dgram(protocol))
660 				return SECCLASS_UDP_SOCKET;
661 			else
662 				return SECCLASS_RAWIP_SOCKET;
663 		default:
664 			return SECCLASS_RAWIP_SOCKET;
665 		}
666 		break;
667 	case PF_NETLINK:
668 		switch (protocol) {
669 		case NETLINK_ROUTE:
670 			return SECCLASS_NETLINK_ROUTE_SOCKET;
671 		case NETLINK_FIREWALL:
672 			return SECCLASS_NETLINK_FIREWALL_SOCKET;
673 		case NETLINK_INET_DIAG:
674 			return SECCLASS_NETLINK_TCPDIAG_SOCKET;
675 		case NETLINK_NFLOG:
676 			return SECCLASS_NETLINK_NFLOG_SOCKET;
677 		case NETLINK_XFRM:
678 			return SECCLASS_NETLINK_XFRM_SOCKET;
679 		case NETLINK_SELINUX:
680 			return SECCLASS_NETLINK_SELINUX_SOCKET;
681 		case NETLINK_AUDIT:
682 			return SECCLASS_NETLINK_AUDIT_SOCKET;
683 		case NETLINK_IP6_FW:
684 			return SECCLASS_NETLINK_IP6FW_SOCKET;
685 		case NETLINK_DNRTMSG:
686 			return SECCLASS_NETLINK_DNRT_SOCKET;
687 		case NETLINK_KOBJECT_UEVENT:
688 			return SECCLASS_NETLINK_KOBJECT_UEVENT_SOCKET;
689 		default:
690 			return SECCLASS_NETLINK_SOCKET;
691 		}
692 	case PF_PACKET:
693 		return SECCLASS_PACKET_SOCKET;
694 	case PF_KEY:
695 		return SECCLASS_KEY_SOCKET;
696 	}
697 
698 	return SECCLASS_SOCKET;
699 }
700 
701 #ifdef CONFIG_PROC_FS
702 static int selinux_proc_get_sid(struct proc_dir_entry *de,
703 				u16 tclass,
704 				u32 *sid)
705 {
706 	int buflen, rc;
707 	char *buffer, *path, *end;
708 
709 	buffer = (char*)__get_free_page(GFP_KERNEL);
710 	if (!buffer)
711 		return -ENOMEM;
712 
713 	buflen = PAGE_SIZE;
714 	end = buffer+buflen;
715 	*--end = '\0';
716 	buflen--;
717 	path = end-1;
718 	*path = '/';
719 	while (de && de != de->parent) {
720 		buflen -= de->namelen + 1;
721 		if (buflen < 0)
722 			break;
723 		end -= de->namelen;
724 		memcpy(end, de->name, de->namelen);
725 		*--end = '/';
726 		path = end;
727 		de = de->parent;
728 	}
729 	rc = security_genfs_sid("proc", path, tclass, sid);
730 	free_page((unsigned long)buffer);
731 	return rc;
732 }
733 #else
734 static int selinux_proc_get_sid(struct proc_dir_entry *de,
735 				u16 tclass,
736 				u32 *sid)
737 {
738 	return -EINVAL;
739 }
740 #endif
741 
742 /* The inode's security attributes must be initialized before first use. */
743 static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dentry)
744 {
745 	struct superblock_security_struct *sbsec = NULL;
746 	struct inode_security_struct *isec = inode->i_security;
747 	u32 sid;
748 	struct dentry *dentry;
749 #define INITCONTEXTLEN 255
750 	char *context = NULL;
751 	unsigned len = 0;
752 	int rc = 0;
753 	int hold_sem = 0;
754 
755 	if (isec->initialized)
756 		goto out;
757 
758 	down(&isec->sem);
759 	hold_sem = 1;
760 	if (isec->initialized)
761 		goto out;
762 
763 	sbsec = inode->i_sb->s_security;
764 	if (!sbsec->initialized) {
765 		/* Defer initialization until selinux_complete_init,
766 		   after the initial policy is loaded and the security
767 		   server is ready to handle calls. */
768 		spin_lock(&sbsec->isec_lock);
769 		if (list_empty(&isec->list))
770 			list_add(&isec->list, &sbsec->isec_head);
771 		spin_unlock(&sbsec->isec_lock);
772 		goto out;
773 	}
774 
775 	switch (sbsec->behavior) {
776 	case SECURITY_FS_USE_XATTR:
777 		if (!inode->i_op->getxattr) {
778 			isec->sid = sbsec->def_sid;
779 			break;
780 		}
781 
782 		/* Need a dentry, since the xattr API requires one.
783 		   Life would be simpler if we could just pass the inode. */
784 		if (opt_dentry) {
785 			/* Called from d_instantiate or d_splice_alias. */
786 			dentry = dget(opt_dentry);
787 		} else {
788 			/* Called from selinux_complete_init, try to find a dentry. */
789 			dentry = d_find_alias(inode);
790 		}
791 		if (!dentry) {
792 			printk(KERN_WARNING "%s:  no dentry for dev=%s "
793 			       "ino=%ld\n", __FUNCTION__, inode->i_sb->s_id,
794 			       inode->i_ino);
795 			goto out;
796 		}
797 
798 		len = INITCONTEXTLEN;
799 		context = kmalloc(len, GFP_KERNEL);
800 		if (!context) {
801 			rc = -ENOMEM;
802 			dput(dentry);
803 			goto out;
804 		}
805 		rc = inode->i_op->getxattr(dentry, XATTR_NAME_SELINUX,
806 					   context, len);
807 		if (rc == -ERANGE) {
808 			/* Need a larger buffer.  Query for the right size. */
809 			rc = inode->i_op->getxattr(dentry, XATTR_NAME_SELINUX,
810 						   NULL, 0);
811 			if (rc < 0) {
812 				dput(dentry);
813 				goto out;
814 			}
815 			kfree(context);
816 			len = rc;
817 			context = kmalloc(len, GFP_KERNEL);
818 			if (!context) {
819 				rc = -ENOMEM;
820 				dput(dentry);
821 				goto out;
822 			}
823 			rc = inode->i_op->getxattr(dentry,
824 						   XATTR_NAME_SELINUX,
825 						   context, len);
826 		}
827 		dput(dentry);
828 		if (rc < 0) {
829 			if (rc != -ENODATA) {
830 				printk(KERN_WARNING "%s:  getxattr returned "
831 				       "%d for dev=%s ino=%ld\n", __FUNCTION__,
832 				       -rc, inode->i_sb->s_id, inode->i_ino);
833 				kfree(context);
834 				goto out;
835 			}
836 			/* Map ENODATA to the default file SID */
837 			sid = sbsec->def_sid;
838 			rc = 0;
839 		} else {
840 			rc = security_context_to_sid_default(context, rc, &sid,
841 			                                     sbsec->def_sid);
842 			if (rc) {
843 				printk(KERN_WARNING "%s:  context_to_sid(%s) "
844 				       "returned %d for dev=%s ino=%ld\n",
845 				       __FUNCTION__, context, -rc,
846 				       inode->i_sb->s_id, inode->i_ino);
847 				kfree(context);
848 				/* Leave with the unlabeled SID */
849 				rc = 0;
850 				break;
851 			}
852 		}
853 		kfree(context);
854 		isec->sid = sid;
855 		break;
856 	case SECURITY_FS_USE_TASK:
857 		isec->sid = isec->task_sid;
858 		break;
859 	case SECURITY_FS_USE_TRANS:
860 		/* Default to the fs SID. */
861 		isec->sid = sbsec->sid;
862 
863 		/* Try to obtain a transition SID. */
864 		isec->sclass = inode_mode_to_security_class(inode->i_mode);
865 		rc = security_transition_sid(isec->task_sid,
866 					     sbsec->sid,
867 					     isec->sclass,
868 					     &sid);
869 		if (rc)
870 			goto out;
871 		isec->sid = sid;
872 		break;
873 	default:
874 		/* Default to the fs SID. */
875 		isec->sid = sbsec->sid;
876 
877 		if (sbsec->proc) {
878 			struct proc_inode *proci = PROC_I(inode);
879 			if (proci->pde) {
880 				isec->sclass = inode_mode_to_security_class(inode->i_mode);
881 				rc = selinux_proc_get_sid(proci->pde,
882 							  isec->sclass,
883 							  &sid);
884 				if (rc)
885 					goto out;
886 				isec->sid = sid;
887 			}
888 		}
889 		break;
890 	}
891 
892 	isec->initialized = 1;
893 
894 out:
895 	if (isec->sclass == SECCLASS_FILE)
896 		isec->sclass = inode_mode_to_security_class(inode->i_mode);
897 
898 	if (hold_sem)
899 		up(&isec->sem);
900 	return rc;
901 }
902 
903 /* Convert a Linux signal to an access vector. */
904 static inline u32 signal_to_av(int sig)
905 {
906 	u32 perm = 0;
907 
908 	switch (sig) {
909 	case SIGCHLD:
910 		/* Commonly granted from child to parent. */
911 		perm = PROCESS__SIGCHLD;
912 		break;
913 	case SIGKILL:
914 		/* Cannot be caught or ignored */
915 		perm = PROCESS__SIGKILL;
916 		break;
917 	case SIGSTOP:
918 		/* Cannot be caught or ignored */
919 		perm = PROCESS__SIGSTOP;
920 		break;
921 	default:
922 		/* All other signals. */
923 		perm = PROCESS__SIGNAL;
924 		break;
925 	}
926 
927 	return perm;
928 }
929 
930 /* Check permission betweeen a pair of tasks, e.g. signal checks,
931    fork check, ptrace check, etc. */
932 static int task_has_perm(struct task_struct *tsk1,
933 			 struct task_struct *tsk2,
934 			 u32 perms)
935 {
936 	struct task_security_struct *tsec1, *tsec2;
937 
938 	tsec1 = tsk1->security;
939 	tsec2 = tsk2->security;
940 	return avc_has_perm(tsec1->sid, tsec2->sid,
941 			    SECCLASS_PROCESS, perms, NULL);
942 }
943 
944 /* Check whether a task is allowed to use a capability. */
945 static int task_has_capability(struct task_struct *tsk,
946 			       int cap)
947 {
948 	struct task_security_struct *tsec;
949 	struct avc_audit_data ad;
950 
951 	tsec = tsk->security;
952 
953 	AVC_AUDIT_DATA_INIT(&ad,CAP);
954 	ad.tsk = tsk;
955 	ad.u.cap = cap;
956 
957 	return avc_has_perm(tsec->sid, tsec->sid,
958 			    SECCLASS_CAPABILITY, CAP_TO_MASK(cap), &ad);
959 }
960 
961 /* Check whether a task is allowed to use a system operation. */
962 static int task_has_system(struct task_struct *tsk,
963 			   u32 perms)
964 {
965 	struct task_security_struct *tsec;
966 
967 	tsec = tsk->security;
968 
969 	return avc_has_perm(tsec->sid, SECINITSID_KERNEL,
970 			    SECCLASS_SYSTEM, perms, NULL);
971 }
972 
973 /* Check whether a task has a particular permission to an inode.
974    The 'adp' parameter is optional and allows other audit
975    data to be passed (e.g. the dentry). */
976 static int inode_has_perm(struct task_struct *tsk,
977 			  struct inode *inode,
978 			  u32 perms,
979 			  struct avc_audit_data *adp)
980 {
981 	struct task_security_struct *tsec;
982 	struct inode_security_struct *isec;
983 	struct avc_audit_data ad;
984 
985 	tsec = tsk->security;
986 	isec = inode->i_security;
987 
988 	if (!adp) {
989 		adp = &ad;
990 		AVC_AUDIT_DATA_INIT(&ad, FS);
991 		ad.u.fs.inode = inode;
992 	}
993 
994 	return avc_has_perm(tsec->sid, isec->sid, isec->sclass, perms, adp);
995 }
996 
997 /* Same as inode_has_perm, but pass explicit audit data containing
998    the dentry to help the auditing code to more easily generate the
999    pathname if needed. */
1000 static inline int dentry_has_perm(struct task_struct *tsk,
1001 				  struct vfsmount *mnt,
1002 				  struct dentry *dentry,
1003 				  u32 av)
1004 {
1005 	struct inode *inode = dentry->d_inode;
1006 	struct avc_audit_data ad;
1007 	AVC_AUDIT_DATA_INIT(&ad,FS);
1008 	ad.u.fs.mnt = mnt;
1009 	ad.u.fs.dentry = dentry;
1010 	return inode_has_perm(tsk, inode, av, &ad);
1011 }
1012 
1013 /* Check whether a task can use an open file descriptor to
1014    access an inode in a given way.  Check access to the
1015    descriptor itself, and then use dentry_has_perm to
1016    check a particular permission to the file.
1017    Access to the descriptor is implicitly granted if it
1018    has the same SID as the process.  If av is zero, then
1019    access to the file is not checked, e.g. for cases
1020    where only the descriptor is affected like seek. */
1021 static inline int file_has_perm(struct task_struct *tsk,
1022 				struct file *file,
1023 				u32 av)
1024 {
1025 	struct task_security_struct *tsec = tsk->security;
1026 	struct file_security_struct *fsec = file->f_security;
1027 	struct vfsmount *mnt = file->f_vfsmnt;
1028 	struct dentry *dentry = file->f_dentry;
1029 	struct inode *inode = dentry->d_inode;
1030 	struct avc_audit_data ad;
1031 	int rc;
1032 
1033 	AVC_AUDIT_DATA_INIT(&ad, FS);
1034 	ad.u.fs.mnt = mnt;
1035 	ad.u.fs.dentry = dentry;
1036 
1037 	if (tsec->sid != fsec->sid) {
1038 		rc = avc_has_perm(tsec->sid, fsec->sid,
1039 				  SECCLASS_FD,
1040 				  FD__USE,
1041 				  &ad);
1042 		if (rc)
1043 			return rc;
1044 	}
1045 
1046 	/* av is zero if only checking access to the descriptor. */
1047 	if (av)
1048 		return inode_has_perm(tsk, inode, av, &ad);
1049 
1050 	return 0;
1051 }
1052 
1053 /* Check whether a task can create a file. */
1054 static int may_create(struct inode *dir,
1055 		      struct dentry *dentry,
1056 		      u16 tclass)
1057 {
1058 	struct task_security_struct *tsec;
1059 	struct inode_security_struct *dsec;
1060 	struct superblock_security_struct *sbsec;
1061 	u32 newsid;
1062 	struct avc_audit_data ad;
1063 	int rc;
1064 
1065 	tsec = current->security;
1066 	dsec = dir->i_security;
1067 	sbsec = dir->i_sb->s_security;
1068 
1069 	AVC_AUDIT_DATA_INIT(&ad, FS);
1070 	ad.u.fs.dentry = dentry;
1071 
1072 	rc = avc_has_perm(tsec->sid, dsec->sid, SECCLASS_DIR,
1073 			  DIR__ADD_NAME | DIR__SEARCH,
1074 			  &ad);
1075 	if (rc)
1076 		return rc;
1077 
1078 	if (tsec->create_sid && sbsec->behavior != SECURITY_FS_USE_MNTPOINT) {
1079 		newsid = tsec->create_sid;
1080 	} else {
1081 		rc = security_transition_sid(tsec->sid, dsec->sid, tclass,
1082 					     &newsid);
1083 		if (rc)
1084 			return rc;
1085 	}
1086 
1087 	rc = avc_has_perm(tsec->sid, newsid, tclass, FILE__CREATE, &ad);
1088 	if (rc)
1089 		return rc;
1090 
1091 	return avc_has_perm(newsid, sbsec->sid,
1092 			    SECCLASS_FILESYSTEM,
1093 			    FILESYSTEM__ASSOCIATE, &ad);
1094 }
1095 
1096 #define MAY_LINK   0
1097 #define MAY_UNLINK 1
1098 #define MAY_RMDIR  2
1099 
1100 /* Check whether a task can link, unlink, or rmdir a file/directory. */
1101 static int may_link(struct inode *dir,
1102 		    struct dentry *dentry,
1103 		    int kind)
1104 
1105 {
1106 	struct task_security_struct *tsec;
1107 	struct inode_security_struct *dsec, *isec;
1108 	struct avc_audit_data ad;
1109 	u32 av;
1110 	int rc;
1111 
1112 	tsec = current->security;
1113 	dsec = dir->i_security;
1114 	isec = dentry->d_inode->i_security;
1115 
1116 	AVC_AUDIT_DATA_INIT(&ad, FS);
1117 	ad.u.fs.dentry = dentry;
1118 
1119 	av = DIR__SEARCH;
1120 	av |= (kind ? DIR__REMOVE_NAME : DIR__ADD_NAME);
1121 	rc = avc_has_perm(tsec->sid, dsec->sid, SECCLASS_DIR, av, &ad);
1122 	if (rc)
1123 		return rc;
1124 
1125 	switch (kind) {
1126 	case MAY_LINK:
1127 		av = FILE__LINK;
1128 		break;
1129 	case MAY_UNLINK:
1130 		av = FILE__UNLINK;
1131 		break;
1132 	case MAY_RMDIR:
1133 		av = DIR__RMDIR;
1134 		break;
1135 	default:
1136 		printk(KERN_WARNING "may_link:  unrecognized kind %d\n", kind);
1137 		return 0;
1138 	}
1139 
1140 	rc = avc_has_perm(tsec->sid, isec->sid, isec->sclass, av, &ad);
1141 	return rc;
1142 }
1143 
1144 static inline int may_rename(struct inode *old_dir,
1145 			     struct dentry *old_dentry,
1146 			     struct inode *new_dir,
1147 			     struct dentry *new_dentry)
1148 {
1149 	struct task_security_struct *tsec;
1150 	struct inode_security_struct *old_dsec, *new_dsec, *old_isec, *new_isec;
1151 	struct avc_audit_data ad;
1152 	u32 av;
1153 	int old_is_dir, new_is_dir;
1154 	int rc;
1155 
1156 	tsec = current->security;
1157 	old_dsec = old_dir->i_security;
1158 	old_isec = old_dentry->d_inode->i_security;
1159 	old_is_dir = S_ISDIR(old_dentry->d_inode->i_mode);
1160 	new_dsec = new_dir->i_security;
1161 
1162 	AVC_AUDIT_DATA_INIT(&ad, FS);
1163 
1164 	ad.u.fs.dentry = old_dentry;
1165 	rc = avc_has_perm(tsec->sid, old_dsec->sid, SECCLASS_DIR,
1166 			  DIR__REMOVE_NAME | DIR__SEARCH, &ad);
1167 	if (rc)
1168 		return rc;
1169 	rc = avc_has_perm(tsec->sid, old_isec->sid,
1170 			  old_isec->sclass, FILE__RENAME, &ad);
1171 	if (rc)
1172 		return rc;
1173 	if (old_is_dir && new_dir != old_dir) {
1174 		rc = avc_has_perm(tsec->sid, old_isec->sid,
1175 				  old_isec->sclass, DIR__REPARENT, &ad);
1176 		if (rc)
1177 			return rc;
1178 	}
1179 
1180 	ad.u.fs.dentry = new_dentry;
1181 	av = DIR__ADD_NAME | DIR__SEARCH;
1182 	if (new_dentry->d_inode)
1183 		av |= DIR__REMOVE_NAME;
1184 	rc = avc_has_perm(tsec->sid, new_dsec->sid, SECCLASS_DIR, av, &ad);
1185 	if (rc)
1186 		return rc;
1187 	if (new_dentry->d_inode) {
1188 		new_isec = new_dentry->d_inode->i_security;
1189 		new_is_dir = S_ISDIR(new_dentry->d_inode->i_mode);
1190 		rc = avc_has_perm(tsec->sid, new_isec->sid,
1191 				  new_isec->sclass,
1192 				  (new_is_dir ? DIR__RMDIR : FILE__UNLINK), &ad);
1193 		if (rc)
1194 			return rc;
1195 	}
1196 
1197 	return 0;
1198 }
1199 
1200 /* Check whether a task can perform a filesystem operation. */
1201 static int superblock_has_perm(struct task_struct *tsk,
1202 			       struct super_block *sb,
1203 			       u32 perms,
1204 			       struct avc_audit_data *ad)
1205 {
1206 	struct task_security_struct *tsec;
1207 	struct superblock_security_struct *sbsec;
1208 
1209 	tsec = tsk->security;
1210 	sbsec = sb->s_security;
1211 	return avc_has_perm(tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM,
1212 			    perms, ad);
1213 }
1214 
1215 /* Convert a Linux mode and permission mask to an access vector. */
1216 static inline u32 file_mask_to_av(int mode, int mask)
1217 {
1218 	u32 av = 0;
1219 
1220 	if ((mode & S_IFMT) != S_IFDIR) {
1221 		if (mask & MAY_EXEC)
1222 			av |= FILE__EXECUTE;
1223 		if (mask & MAY_READ)
1224 			av |= FILE__READ;
1225 
1226 		if (mask & MAY_APPEND)
1227 			av |= FILE__APPEND;
1228 		else if (mask & MAY_WRITE)
1229 			av |= FILE__WRITE;
1230 
1231 	} else {
1232 		if (mask & MAY_EXEC)
1233 			av |= DIR__SEARCH;
1234 		if (mask & MAY_WRITE)
1235 			av |= DIR__WRITE;
1236 		if (mask & MAY_READ)
1237 			av |= DIR__READ;
1238 	}
1239 
1240 	return av;
1241 }
1242 
1243 /* Convert a Linux file to an access vector. */
1244 static inline u32 file_to_av(struct file *file)
1245 {
1246 	u32 av = 0;
1247 
1248 	if (file->f_mode & FMODE_READ)
1249 		av |= FILE__READ;
1250 	if (file->f_mode & FMODE_WRITE) {
1251 		if (file->f_flags & O_APPEND)
1252 			av |= FILE__APPEND;
1253 		else
1254 			av |= FILE__WRITE;
1255 	}
1256 
1257 	return av;
1258 }
1259 
1260 /* Set an inode's SID to a specified value. */
1261 static int inode_security_set_sid(struct inode *inode, u32 sid)
1262 {
1263 	struct inode_security_struct *isec = inode->i_security;
1264 	struct superblock_security_struct *sbsec = inode->i_sb->s_security;
1265 
1266 	if (!sbsec->initialized) {
1267 		/* Defer initialization to selinux_complete_init. */
1268 		return 0;
1269 	}
1270 
1271 	down(&isec->sem);
1272 	isec->sclass = inode_mode_to_security_class(inode->i_mode);
1273 	isec->sid = sid;
1274 	isec->initialized = 1;
1275 	up(&isec->sem);
1276 	return 0;
1277 }
1278 
1279 /* Hook functions begin here. */
1280 
1281 static int selinux_ptrace(struct task_struct *parent, struct task_struct *child)
1282 {
1283 	struct task_security_struct *psec = parent->security;
1284 	struct task_security_struct *csec = child->security;
1285 	int rc;
1286 
1287 	rc = secondary_ops->ptrace(parent,child);
1288 	if (rc)
1289 		return rc;
1290 
1291 	rc = task_has_perm(parent, child, PROCESS__PTRACE);
1292 	/* Save the SID of the tracing process for later use in apply_creds. */
1293 	if (!rc)
1294 		csec->ptrace_sid = psec->sid;
1295 	return rc;
1296 }
1297 
1298 static int selinux_capget(struct task_struct *target, kernel_cap_t *effective,
1299                           kernel_cap_t *inheritable, kernel_cap_t *permitted)
1300 {
1301 	int error;
1302 
1303 	error = task_has_perm(current, target, PROCESS__GETCAP);
1304 	if (error)
1305 		return error;
1306 
1307 	return secondary_ops->capget(target, effective, inheritable, permitted);
1308 }
1309 
1310 static int selinux_capset_check(struct task_struct *target, kernel_cap_t *effective,
1311                                 kernel_cap_t *inheritable, kernel_cap_t *permitted)
1312 {
1313 	int error;
1314 
1315 	error = secondary_ops->capset_check(target, effective, inheritable, permitted);
1316 	if (error)
1317 		return error;
1318 
1319 	return task_has_perm(current, target, PROCESS__SETCAP);
1320 }
1321 
1322 static void selinux_capset_set(struct task_struct *target, kernel_cap_t *effective,
1323                                kernel_cap_t *inheritable, kernel_cap_t *permitted)
1324 {
1325 	secondary_ops->capset_set(target, effective, inheritable, permitted);
1326 }
1327 
1328 static int selinux_capable(struct task_struct *tsk, int cap)
1329 {
1330 	int rc;
1331 
1332 	rc = secondary_ops->capable(tsk, cap);
1333 	if (rc)
1334 		return rc;
1335 
1336 	return task_has_capability(tsk,cap);
1337 }
1338 
1339 static int selinux_sysctl(ctl_table *table, int op)
1340 {
1341 	int error = 0;
1342 	u32 av;
1343 	struct task_security_struct *tsec;
1344 	u32 tsid;
1345 	int rc;
1346 
1347 	rc = secondary_ops->sysctl(table, op);
1348 	if (rc)
1349 		return rc;
1350 
1351 	tsec = current->security;
1352 
1353 	rc = selinux_proc_get_sid(table->de, (op == 001) ?
1354 	                          SECCLASS_DIR : SECCLASS_FILE, &tsid);
1355 	if (rc) {
1356 		/* Default to the well-defined sysctl SID. */
1357 		tsid = SECINITSID_SYSCTL;
1358 	}
1359 
1360 	/* The op values are "defined" in sysctl.c, thereby creating
1361 	 * a bad coupling between this module and sysctl.c */
1362 	if(op == 001) {
1363 		error = avc_has_perm(tsec->sid, tsid,
1364 				     SECCLASS_DIR, DIR__SEARCH, NULL);
1365 	} else {
1366 		av = 0;
1367 		if (op & 004)
1368 			av |= FILE__READ;
1369 		if (op & 002)
1370 			av |= FILE__WRITE;
1371 		if (av)
1372 			error = avc_has_perm(tsec->sid, tsid,
1373 					     SECCLASS_FILE, av, NULL);
1374         }
1375 
1376 	return error;
1377 }
1378 
1379 static int selinux_quotactl(int cmds, int type, int id, struct super_block *sb)
1380 {
1381 	int rc = 0;
1382 
1383 	if (!sb)
1384 		return 0;
1385 
1386 	switch (cmds) {
1387 		case Q_SYNC:
1388 		case Q_QUOTAON:
1389 		case Q_QUOTAOFF:
1390 	        case Q_SETINFO:
1391 		case Q_SETQUOTA:
1392 			rc = superblock_has_perm(current,
1393 						 sb,
1394 						 FILESYSTEM__QUOTAMOD, NULL);
1395 			break;
1396 	        case Q_GETFMT:
1397 	        case Q_GETINFO:
1398 		case Q_GETQUOTA:
1399 			rc = superblock_has_perm(current,
1400 						 sb,
1401 						 FILESYSTEM__QUOTAGET, NULL);
1402 			break;
1403 		default:
1404 			rc = 0;  /* let the kernel handle invalid cmds */
1405 			break;
1406 	}
1407 	return rc;
1408 }
1409 
1410 static int selinux_quota_on(struct dentry *dentry)
1411 {
1412 	return dentry_has_perm(current, NULL, dentry, FILE__QUOTAON);
1413 }
1414 
1415 static int selinux_syslog(int type)
1416 {
1417 	int rc;
1418 
1419 	rc = secondary_ops->syslog(type);
1420 	if (rc)
1421 		return rc;
1422 
1423 	switch (type) {
1424 		case 3:         /* Read last kernel messages */
1425 		case 10:        /* Return size of the log buffer */
1426 			rc = task_has_system(current, SYSTEM__SYSLOG_READ);
1427 			break;
1428 		case 6:         /* Disable logging to console */
1429 		case 7:         /* Enable logging to console */
1430 		case 8:		/* Set level of messages printed to console */
1431 			rc = task_has_system(current, SYSTEM__SYSLOG_CONSOLE);
1432 			break;
1433 		case 0:         /* Close log */
1434 		case 1:         /* Open log */
1435 		case 2:         /* Read from log */
1436 		case 4:         /* Read/clear last kernel messages */
1437 		case 5:         /* Clear ring buffer */
1438 		default:
1439 			rc = task_has_system(current, SYSTEM__SYSLOG_MOD);
1440 			break;
1441 	}
1442 	return rc;
1443 }
1444 
1445 /*
1446  * Check that a process has enough memory to allocate a new virtual
1447  * mapping. 0 means there is enough memory for the allocation to
1448  * succeed and -ENOMEM implies there is not.
1449  *
1450  * Note that secondary_ops->capable and task_has_perm_noaudit return 0
1451  * if the capability is granted, but __vm_enough_memory requires 1 if
1452  * the capability is granted.
1453  *
1454  * Do not audit the selinux permission check, as this is applied to all
1455  * processes that allocate mappings.
1456  */
1457 static int selinux_vm_enough_memory(long pages)
1458 {
1459 	int rc, cap_sys_admin = 0;
1460 	struct task_security_struct *tsec = current->security;
1461 
1462 	rc = secondary_ops->capable(current, CAP_SYS_ADMIN);
1463 	if (rc == 0)
1464 		rc = avc_has_perm_noaudit(tsec->sid, tsec->sid,
1465 					SECCLASS_CAPABILITY,
1466 					CAP_TO_MASK(CAP_SYS_ADMIN),
1467 					NULL);
1468 
1469 	if (rc == 0)
1470 		cap_sys_admin = 1;
1471 
1472 	return __vm_enough_memory(pages, cap_sys_admin);
1473 }
1474 
1475 /* binprm security operations */
1476 
1477 static int selinux_bprm_alloc_security(struct linux_binprm *bprm)
1478 {
1479 	struct bprm_security_struct *bsec;
1480 
1481 	bsec = kzalloc(sizeof(struct bprm_security_struct), GFP_KERNEL);
1482 	if (!bsec)
1483 		return -ENOMEM;
1484 
1485 	bsec->magic = SELINUX_MAGIC;
1486 	bsec->bprm = bprm;
1487 	bsec->sid = SECINITSID_UNLABELED;
1488 	bsec->set = 0;
1489 
1490 	bprm->security = bsec;
1491 	return 0;
1492 }
1493 
1494 static int selinux_bprm_set_security(struct linux_binprm *bprm)
1495 {
1496 	struct task_security_struct *tsec;
1497 	struct inode *inode = bprm->file->f_dentry->d_inode;
1498 	struct inode_security_struct *isec;
1499 	struct bprm_security_struct *bsec;
1500 	u32 newsid;
1501 	struct avc_audit_data ad;
1502 	int rc;
1503 
1504 	rc = secondary_ops->bprm_set_security(bprm);
1505 	if (rc)
1506 		return rc;
1507 
1508 	bsec = bprm->security;
1509 
1510 	if (bsec->set)
1511 		return 0;
1512 
1513 	tsec = current->security;
1514 	isec = inode->i_security;
1515 
1516 	/* Default to the current task SID. */
1517 	bsec->sid = tsec->sid;
1518 
1519 	/* Reset create SID on execve. */
1520 	tsec->create_sid = 0;
1521 
1522 	if (tsec->exec_sid) {
1523 		newsid = tsec->exec_sid;
1524 		/* Reset exec SID on execve. */
1525 		tsec->exec_sid = 0;
1526 	} else {
1527 		/* Check for a default transition on this program. */
1528 		rc = security_transition_sid(tsec->sid, isec->sid,
1529 		                             SECCLASS_PROCESS, &newsid);
1530 		if (rc)
1531 			return rc;
1532 	}
1533 
1534 	AVC_AUDIT_DATA_INIT(&ad, FS);
1535 	ad.u.fs.mnt = bprm->file->f_vfsmnt;
1536 	ad.u.fs.dentry = bprm->file->f_dentry;
1537 
1538 	if (bprm->file->f_vfsmnt->mnt_flags & MNT_NOSUID)
1539 		newsid = tsec->sid;
1540 
1541         if (tsec->sid == newsid) {
1542 		rc = avc_has_perm(tsec->sid, isec->sid,
1543 				  SECCLASS_FILE, FILE__EXECUTE_NO_TRANS, &ad);
1544 		if (rc)
1545 			return rc;
1546 	} else {
1547 		/* Check permissions for the transition. */
1548 		rc = avc_has_perm(tsec->sid, newsid,
1549 				  SECCLASS_PROCESS, PROCESS__TRANSITION, &ad);
1550 		if (rc)
1551 			return rc;
1552 
1553 		rc = avc_has_perm(newsid, isec->sid,
1554 				  SECCLASS_FILE, FILE__ENTRYPOINT, &ad);
1555 		if (rc)
1556 			return rc;
1557 
1558 		/* Clear any possibly unsafe personality bits on exec: */
1559 		current->personality &= ~PER_CLEAR_ON_SETID;
1560 
1561 		/* Set the security field to the new SID. */
1562 		bsec->sid = newsid;
1563 	}
1564 
1565 	bsec->set = 1;
1566 	return 0;
1567 }
1568 
1569 static int selinux_bprm_check_security (struct linux_binprm *bprm)
1570 {
1571 	return secondary_ops->bprm_check_security(bprm);
1572 }
1573 
1574 
1575 static int selinux_bprm_secureexec (struct linux_binprm *bprm)
1576 {
1577 	struct task_security_struct *tsec = current->security;
1578 	int atsecure = 0;
1579 
1580 	if (tsec->osid != tsec->sid) {
1581 		/* Enable secure mode for SIDs transitions unless
1582 		   the noatsecure permission is granted between
1583 		   the two SIDs, i.e. ahp returns 0. */
1584 		atsecure = avc_has_perm(tsec->osid, tsec->sid,
1585 					 SECCLASS_PROCESS,
1586 					 PROCESS__NOATSECURE, NULL);
1587 	}
1588 
1589 	return (atsecure || secondary_ops->bprm_secureexec(bprm));
1590 }
1591 
1592 static void selinux_bprm_free_security(struct linux_binprm *bprm)
1593 {
1594 	kfree(bprm->security);
1595 	bprm->security = NULL;
1596 }
1597 
1598 extern struct vfsmount *selinuxfs_mount;
1599 extern struct dentry *selinux_null;
1600 
1601 /* Derived from fs/exec.c:flush_old_files. */
1602 static inline void flush_unauthorized_files(struct files_struct * files)
1603 {
1604 	struct avc_audit_data ad;
1605 	struct file *file, *devnull = NULL;
1606 	struct tty_struct *tty = current->signal->tty;
1607 	struct fdtable *fdt;
1608 	long j = -1;
1609 
1610 	if (tty) {
1611 		file_list_lock();
1612 		file = list_entry(tty->tty_files.next, typeof(*file), f_u.fu_list);
1613 		if (file) {
1614 			/* Revalidate access to controlling tty.
1615 			   Use inode_has_perm on the tty inode directly rather
1616 			   than using file_has_perm, as this particular open
1617 			   file may belong to another process and we are only
1618 			   interested in the inode-based check here. */
1619 			struct inode *inode = file->f_dentry->d_inode;
1620 			if (inode_has_perm(current, inode,
1621 					   FILE__READ | FILE__WRITE, NULL)) {
1622 				/* Reset controlling tty. */
1623 				current->signal->tty = NULL;
1624 				current->signal->tty_old_pgrp = 0;
1625 			}
1626 		}
1627 		file_list_unlock();
1628 	}
1629 
1630 	/* Revalidate access to inherited open files. */
1631 
1632 	AVC_AUDIT_DATA_INIT(&ad,FS);
1633 
1634 	spin_lock(&files->file_lock);
1635 	for (;;) {
1636 		unsigned long set, i;
1637 		int fd;
1638 
1639 		j++;
1640 		i = j * __NFDBITS;
1641 		fdt = files_fdtable(files);
1642 		if (i >= fdt->max_fds || i >= fdt->max_fdset)
1643 			break;
1644 		set = fdt->open_fds->fds_bits[j];
1645 		if (!set)
1646 			continue;
1647 		spin_unlock(&files->file_lock);
1648 		for ( ; set ; i++,set >>= 1) {
1649 			if (set & 1) {
1650 				file = fget(i);
1651 				if (!file)
1652 					continue;
1653 				if (file_has_perm(current,
1654 						  file,
1655 						  file_to_av(file))) {
1656 					sys_close(i);
1657 					fd = get_unused_fd();
1658 					if (fd != i) {
1659 						if (fd >= 0)
1660 							put_unused_fd(fd);
1661 						fput(file);
1662 						continue;
1663 					}
1664 					if (devnull) {
1665 						rcuref_inc(&devnull->f_count);
1666 					} else {
1667 						devnull = dentry_open(dget(selinux_null), mntget(selinuxfs_mount), O_RDWR);
1668 						if (!devnull) {
1669 							put_unused_fd(fd);
1670 							fput(file);
1671 							continue;
1672 						}
1673 					}
1674 					fd_install(fd, devnull);
1675 				}
1676 				fput(file);
1677 			}
1678 		}
1679 		spin_lock(&files->file_lock);
1680 
1681 	}
1682 	spin_unlock(&files->file_lock);
1683 }
1684 
1685 static void selinux_bprm_apply_creds(struct linux_binprm *bprm, int unsafe)
1686 {
1687 	struct task_security_struct *tsec;
1688 	struct bprm_security_struct *bsec;
1689 	u32 sid;
1690 	int rc;
1691 
1692 	secondary_ops->bprm_apply_creds(bprm, unsafe);
1693 
1694 	tsec = current->security;
1695 
1696 	bsec = bprm->security;
1697 	sid = bsec->sid;
1698 
1699 	tsec->osid = tsec->sid;
1700 	bsec->unsafe = 0;
1701 	if (tsec->sid != sid) {
1702 		/* Check for shared state.  If not ok, leave SID
1703 		   unchanged and kill. */
1704 		if (unsafe & LSM_UNSAFE_SHARE) {
1705 			rc = avc_has_perm(tsec->sid, sid, SECCLASS_PROCESS,
1706 					PROCESS__SHARE, NULL);
1707 			if (rc) {
1708 				bsec->unsafe = 1;
1709 				return;
1710 			}
1711 		}
1712 
1713 		/* Check for ptracing, and update the task SID if ok.
1714 		   Otherwise, leave SID unchanged and kill. */
1715 		if (unsafe & (LSM_UNSAFE_PTRACE | LSM_UNSAFE_PTRACE_CAP)) {
1716 			rc = avc_has_perm(tsec->ptrace_sid, sid,
1717 					  SECCLASS_PROCESS, PROCESS__PTRACE,
1718 					  NULL);
1719 			if (rc) {
1720 				bsec->unsafe = 1;
1721 				return;
1722 			}
1723 		}
1724 		tsec->sid = sid;
1725 	}
1726 }
1727 
1728 /*
1729  * called after apply_creds without the task lock held
1730  */
1731 static void selinux_bprm_post_apply_creds(struct linux_binprm *bprm)
1732 {
1733 	struct task_security_struct *tsec;
1734 	struct rlimit *rlim, *initrlim;
1735 	struct itimerval itimer;
1736 	struct bprm_security_struct *bsec;
1737 	int rc, i;
1738 
1739 	tsec = current->security;
1740 	bsec = bprm->security;
1741 
1742 	if (bsec->unsafe) {
1743 		force_sig_specific(SIGKILL, current);
1744 		return;
1745 	}
1746 	if (tsec->osid == tsec->sid)
1747 		return;
1748 
1749 	/* Close files for which the new task SID is not authorized. */
1750 	flush_unauthorized_files(current->files);
1751 
1752 	/* Check whether the new SID can inherit signal state
1753 	   from the old SID.  If not, clear itimers to avoid
1754 	   subsequent signal generation and flush and unblock
1755 	   signals. This must occur _after_ the task SID has
1756 	  been updated so that any kill done after the flush
1757 	  will be checked against the new SID. */
1758 	rc = avc_has_perm(tsec->osid, tsec->sid, SECCLASS_PROCESS,
1759 			  PROCESS__SIGINH, NULL);
1760 	if (rc) {
1761 		memset(&itimer, 0, sizeof itimer);
1762 		for (i = 0; i < 3; i++)
1763 			do_setitimer(i, &itimer, NULL);
1764 		flush_signals(current);
1765 		spin_lock_irq(&current->sighand->siglock);
1766 		flush_signal_handlers(current, 1);
1767 		sigemptyset(&current->blocked);
1768 		recalc_sigpending();
1769 		spin_unlock_irq(&current->sighand->siglock);
1770 	}
1771 
1772 	/* Check whether the new SID can inherit resource limits
1773 	   from the old SID.  If not, reset all soft limits to
1774 	   the lower of the current task's hard limit and the init
1775 	   task's soft limit.  Note that the setting of hard limits
1776 	   (even to lower them) can be controlled by the setrlimit
1777 	   check. The inclusion of the init task's soft limit into
1778 	   the computation is to avoid resetting soft limits higher
1779 	   than the default soft limit for cases where the default
1780 	   is lower than the hard limit, e.g. RLIMIT_CORE or
1781 	   RLIMIT_STACK.*/
1782 	rc = avc_has_perm(tsec->osid, tsec->sid, SECCLASS_PROCESS,
1783 			  PROCESS__RLIMITINH, NULL);
1784 	if (rc) {
1785 		for (i = 0; i < RLIM_NLIMITS; i++) {
1786 			rlim = current->signal->rlim + i;
1787 			initrlim = init_task.signal->rlim+i;
1788 			rlim->rlim_cur = min(rlim->rlim_max,initrlim->rlim_cur);
1789 		}
1790 		if (current->signal->rlim[RLIMIT_CPU].rlim_cur != RLIM_INFINITY) {
1791 			/*
1792 			 * This will cause RLIMIT_CPU calculations
1793 			 * to be refigured.
1794 			 */
1795 			current->it_prof_expires = jiffies_to_cputime(1);
1796 		}
1797 	}
1798 
1799 	/* Wake up the parent if it is waiting so that it can
1800 	   recheck wait permission to the new task SID. */
1801 	wake_up_interruptible(&current->parent->signal->wait_chldexit);
1802 }
1803 
1804 /* superblock security operations */
1805 
1806 static int selinux_sb_alloc_security(struct super_block *sb)
1807 {
1808 	return superblock_alloc_security(sb);
1809 }
1810 
1811 static void selinux_sb_free_security(struct super_block *sb)
1812 {
1813 	superblock_free_security(sb);
1814 }
1815 
1816 static inline int match_prefix(char *prefix, int plen, char *option, int olen)
1817 {
1818 	if (plen > olen)
1819 		return 0;
1820 
1821 	return !memcmp(prefix, option, plen);
1822 }
1823 
1824 static inline int selinux_option(char *option, int len)
1825 {
1826 	return (match_prefix("context=", sizeof("context=")-1, option, len) ||
1827 	        match_prefix("fscontext=", sizeof("fscontext=")-1, option, len) ||
1828 	        match_prefix("defcontext=", sizeof("defcontext=")-1, option, len));
1829 }
1830 
1831 static inline void take_option(char **to, char *from, int *first, int len)
1832 {
1833 	if (!*first) {
1834 		**to = ',';
1835 		*to += 1;
1836 	}
1837 	else
1838 		*first = 0;
1839 	memcpy(*to, from, len);
1840 	*to += len;
1841 }
1842 
1843 static int selinux_sb_copy_data(struct file_system_type *type, void *orig, void *copy)
1844 {
1845 	int fnosec, fsec, rc = 0;
1846 	char *in_save, *in_curr, *in_end;
1847 	char *sec_curr, *nosec_save, *nosec;
1848 
1849 	in_curr = orig;
1850 	sec_curr = copy;
1851 
1852 	/* Binary mount data: just copy */
1853 	if (type->fs_flags & FS_BINARY_MOUNTDATA) {
1854 		copy_page(sec_curr, in_curr);
1855 		goto out;
1856 	}
1857 
1858 	nosec = (char *)get_zeroed_page(GFP_KERNEL);
1859 	if (!nosec) {
1860 		rc = -ENOMEM;
1861 		goto out;
1862 	}
1863 
1864 	nosec_save = nosec;
1865 	fnosec = fsec = 1;
1866 	in_save = in_end = orig;
1867 
1868 	do {
1869 		if (*in_end == ',' || *in_end == '\0') {
1870 			int len = in_end - in_curr;
1871 
1872 			if (selinux_option(in_curr, len))
1873 				take_option(&sec_curr, in_curr, &fsec, len);
1874 			else
1875 				take_option(&nosec, in_curr, &fnosec, len);
1876 
1877 			in_curr = in_end + 1;
1878 		}
1879 	} while (*in_end++);
1880 
1881 	strcpy(in_save, nosec_save);
1882 	free_page((unsigned long)nosec_save);
1883 out:
1884 	return rc;
1885 }
1886 
1887 static int selinux_sb_kern_mount(struct super_block *sb, void *data)
1888 {
1889 	struct avc_audit_data ad;
1890 	int rc;
1891 
1892 	rc = superblock_doinit(sb, data);
1893 	if (rc)
1894 		return rc;
1895 
1896 	AVC_AUDIT_DATA_INIT(&ad,FS);
1897 	ad.u.fs.dentry = sb->s_root;
1898 	return superblock_has_perm(current, sb, FILESYSTEM__MOUNT, &ad);
1899 }
1900 
1901 static int selinux_sb_statfs(struct super_block *sb)
1902 {
1903 	struct avc_audit_data ad;
1904 
1905 	AVC_AUDIT_DATA_INIT(&ad,FS);
1906 	ad.u.fs.dentry = sb->s_root;
1907 	return superblock_has_perm(current, sb, FILESYSTEM__GETATTR, &ad);
1908 }
1909 
1910 static int selinux_mount(char * dev_name,
1911                          struct nameidata *nd,
1912                          char * type,
1913                          unsigned long flags,
1914                          void * data)
1915 {
1916 	int rc;
1917 
1918 	rc = secondary_ops->sb_mount(dev_name, nd, type, flags, data);
1919 	if (rc)
1920 		return rc;
1921 
1922 	if (flags & MS_REMOUNT)
1923 		return superblock_has_perm(current, nd->mnt->mnt_sb,
1924 		                           FILESYSTEM__REMOUNT, NULL);
1925 	else
1926 		return dentry_has_perm(current, nd->mnt, nd->dentry,
1927 		                       FILE__MOUNTON);
1928 }
1929 
1930 static int selinux_umount(struct vfsmount *mnt, int flags)
1931 {
1932 	int rc;
1933 
1934 	rc = secondary_ops->sb_umount(mnt, flags);
1935 	if (rc)
1936 		return rc;
1937 
1938 	return superblock_has_perm(current,mnt->mnt_sb,
1939 	                           FILESYSTEM__UNMOUNT,NULL);
1940 }
1941 
1942 /* inode security operations */
1943 
1944 static int selinux_inode_alloc_security(struct inode *inode)
1945 {
1946 	return inode_alloc_security(inode);
1947 }
1948 
1949 static void selinux_inode_free_security(struct inode *inode)
1950 {
1951 	inode_free_security(inode);
1952 }
1953 
1954 static int selinux_inode_init_security(struct inode *inode, struct inode *dir,
1955 				       char **name, void **value,
1956 				       size_t *len)
1957 {
1958 	struct task_security_struct *tsec;
1959 	struct inode_security_struct *dsec;
1960 	struct superblock_security_struct *sbsec;
1961 	struct inode_security_struct *isec;
1962 	u32 newsid, clen;
1963 	int rc;
1964 	char *namep = NULL, *context;
1965 
1966 	tsec = current->security;
1967 	dsec = dir->i_security;
1968 	sbsec = dir->i_sb->s_security;
1969 	isec = inode->i_security;
1970 
1971 	if (tsec->create_sid && sbsec->behavior != SECURITY_FS_USE_MNTPOINT) {
1972 		newsid = tsec->create_sid;
1973 	} else {
1974 		rc = security_transition_sid(tsec->sid, dsec->sid,
1975 					     inode_mode_to_security_class(inode->i_mode),
1976 					     &newsid);
1977 		if (rc) {
1978 			printk(KERN_WARNING "%s:  "
1979 			       "security_transition_sid failed, rc=%d (dev=%s "
1980 			       "ino=%ld)\n",
1981 			       __FUNCTION__,
1982 			       -rc, inode->i_sb->s_id, inode->i_ino);
1983 			return rc;
1984 		}
1985 	}
1986 
1987 	inode_security_set_sid(inode, newsid);
1988 
1989 	if (sbsec->behavior == SECURITY_FS_USE_MNTPOINT)
1990 		return -EOPNOTSUPP;
1991 
1992 	if (name) {
1993 		namep = kstrdup(XATTR_SELINUX_SUFFIX, GFP_KERNEL);
1994 		if (!namep)
1995 			return -ENOMEM;
1996 		*name = namep;
1997 	}
1998 
1999 	if (value && len) {
2000 		rc = security_sid_to_context(newsid, &context, &clen);
2001 		if (rc) {
2002 			kfree(namep);
2003 			return rc;
2004 		}
2005 		*value = context;
2006 		*len = clen;
2007 	}
2008 
2009 	return 0;
2010 }
2011 
2012 static int selinux_inode_create(struct inode *dir, struct dentry *dentry, int mask)
2013 {
2014 	return may_create(dir, dentry, SECCLASS_FILE);
2015 }
2016 
2017 static int selinux_inode_link(struct dentry *old_dentry, struct inode *dir, struct dentry *new_dentry)
2018 {
2019 	int rc;
2020 
2021 	rc = secondary_ops->inode_link(old_dentry,dir,new_dentry);
2022 	if (rc)
2023 		return rc;
2024 	return may_link(dir, old_dentry, MAY_LINK);
2025 }
2026 
2027 static int selinux_inode_unlink(struct inode *dir, struct dentry *dentry)
2028 {
2029 	int rc;
2030 
2031 	rc = secondary_ops->inode_unlink(dir, dentry);
2032 	if (rc)
2033 		return rc;
2034 	return may_link(dir, dentry, MAY_UNLINK);
2035 }
2036 
2037 static int selinux_inode_symlink(struct inode *dir, struct dentry *dentry, const char *name)
2038 {
2039 	return may_create(dir, dentry, SECCLASS_LNK_FILE);
2040 }
2041 
2042 static int selinux_inode_mkdir(struct inode *dir, struct dentry *dentry, int mask)
2043 {
2044 	return may_create(dir, dentry, SECCLASS_DIR);
2045 }
2046 
2047 static int selinux_inode_rmdir(struct inode *dir, struct dentry *dentry)
2048 {
2049 	return may_link(dir, dentry, MAY_RMDIR);
2050 }
2051 
2052 static int selinux_inode_mknod(struct inode *dir, struct dentry *dentry, int mode, dev_t dev)
2053 {
2054 	int rc;
2055 
2056 	rc = secondary_ops->inode_mknod(dir, dentry, mode, dev);
2057 	if (rc)
2058 		return rc;
2059 
2060 	return may_create(dir, dentry, inode_mode_to_security_class(mode));
2061 }
2062 
2063 static int selinux_inode_rename(struct inode *old_inode, struct dentry *old_dentry,
2064                                 struct inode *new_inode, struct dentry *new_dentry)
2065 {
2066 	return may_rename(old_inode, old_dentry, new_inode, new_dentry);
2067 }
2068 
2069 static int selinux_inode_readlink(struct dentry *dentry)
2070 {
2071 	return dentry_has_perm(current, NULL, dentry, FILE__READ);
2072 }
2073 
2074 static int selinux_inode_follow_link(struct dentry *dentry, struct nameidata *nameidata)
2075 {
2076 	int rc;
2077 
2078 	rc = secondary_ops->inode_follow_link(dentry,nameidata);
2079 	if (rc)
2080 		return rc;
2081 	return dentry_has_perm(current, NULL, dentry, FILE__READ);
2082 }
2083 
2084 static int selinux_inode_permission(struct inode *inode, int mask,
2085 				    struct nameidata *nd)
2086 {
2087 	int rc;
2088 
2089 	rc = secondary_ops->inode_permission(inode, mask, nd);
2090 	if (rc)
2091 		return rc;
2092 
2093 	if (!mask) {
2094 		/* No permission to check.  Existence test. */
2095 		return 0;
2096 	}
2097 
2098 	return inode_has_perm(current, inode,
2099 			       file_mask_to_av(inode->i_mode, mask), NULL);
2100 }
2101 
2102 static int selinux_inode_setattr(struct dentry *dentry, struct iattr *iattr)
2103 {
2104 	int rc;
2105 
2106 	rc = secondary_ops->inode_setattr(dentry, iattr);
2107 	if (rc)
2108 		return rc;
2109 
2110 	if (iattr->ia_valid & ATTR_FORCE)
2111 		return 0;
2112 
2113 	if (iattr->ia_valid & (ATTR_MODE | ATTR_UID | ATTR_GID |
2114 			       ATTR_ATIME_SET | ATTR_MTIME_SET))
2115 		return dentry_has_perm(current, NULL, dentry, FILE__SETATTR);
2116 
2117 	return dentry_has_perm(current, NULL, dentry, FILE__WRITE);
2118 }
2119 
2120 static int selinux_inode_getattr(struct vfsmount *mnt, struct dentry *dentry)
2121 {
2122 	return dentry_has_perm(current, mnt, dentry, FILE__GETATTR);
2123 }
2124 
2125 static int selinux_inode_setxattr(struct dentry *dentry, char *name, void *value, size_t size, int flags)
2126 {
2127 	struct task_security_struct *tsec = current->security;
2128 	struct inode *inode = dentry->d_inode;
2129 	struct inode_security_struct *isec = inode->i_security;
2130 	struct superblock_security_struct *sbsec;
2131 	struct avc_audit_data ad;
2132 	u32 newsid;
2133 	int rc = 0;
2134 
2135 	if (strcmp(name, XATTR_NAME_SELINUX)) {
2136 		if (!strncmp(name, XATTR_SECURITY_PREFIX,
2137 			     sizeof XATTR_SECURITY_PREFIX - 1) &&
2138 		    !capable(CAP_SYS_ADMIN)) {
2139 			/* A different attribute in the security namespace.
2140 			   Restrict to administrator. */
2141 			return -EPERM;
2142 		}
2143 
2144 		/* Not an attribute we recognize, so just check the
2145 		   ordinary setattr permission. */
2146 		return dentry_has_perm(current, NULL, dentry, FILE__SETATTR);
2147 	}
2148 
2149 	sbsec = inode->i_sb->s_security;
2150 	if (sbsec->behavior == SECURITY_FS_USE_MNTPOINT)
2151 		return -EOPNOTSUPP;
2152 
2153 	if ((current->fsuid != inode->i_uid) && !capable(CAP_FOWNER))
2154 		return -EPERM;
2155 
2156 	AVC_AUDIT_DATA_INIT(&ad,FS);
2157 	ad.u.fs.dentry = dentry;
2158 
2159 	rc = avc_has_perm(tsec->sid, isec->sid, isec->sclass,
2160 			  FILE__RELABELFROM, &ad);
2161 	if (rc)
2162 		return rc;
2163 
2164 	rc = security_context_to_sid(value, size, &newsid);
2165 	if (rc)
2166 		return rc;
2167 
2168 	rc = avc_has_perm(tsec->sid, newsid, isec->sclass,
2169 			  FILE__RELABELTO, &ad);
2170 	if (rc)
2171 		return rc;
2172 
2173 	rc = security_validate_transition(isec->sid, newsid, tsec->sid,
2174 	                                  isec->sclass);
2175 	if (rc)
2176 		return rc;
2177 
2178 	return avc_has_perm(newsid,
2179 			    sbsec->sid,
2180 			    SECCLASS_FILESYSTEM,
2181 			    FILESYSTEM__ASSOCIATE,
2182 			    &ad);
2183 }
2184 
2185 static void selinux_inode_post_setxattr(struct dentry *dentry, char *name,
2186                                         void *value, size_t size, int flags)
2187 {
2188 	struct inode *inode = dentry->d_inode;
2189 	struct inode_security_struct *isec = inode->i_security;
2190 	u32 newsid;
2191 	int rc;
2192 
2193 	if (strcmp(name, XATTR_NAME_SELINUX)) {
2194 		/* Not an attribute we recognize, so nothing to do. */
2195 		return;
2196 	}
2197 
2198 	rc = security_context_to_sid(value, size, &newsid);
2199 	if (rc) {
2200 		printk(KERN_WARNING "%s:  unable to obtain SID for context "
2201 		       "%s, rc=%d\n", __FUNCTION__, (char*)value, -rc);
2202 		return;
2203 	}
2204 
2205 	isec->sid = newsid;
2206 	return;
2207 }
2208 
2209 static int selinux_inode_getxattr (struct dentry *dentry, char *name)
2210 {
2211 	return dentry_has_perm(current, NULL, dentry, FILE__GETATTR);
2212 }
2213 
2214 static int selinux_inode_listxattr (struct dentry *dentry)
2215 {
2216 	return dentry_has_perm(current, NULL, dentry, FILE__GETATTR);
2217 }
2218 
2219 static int selinux_inode_removexattr (struct dentry *dentry, char *name)
2220 {
2221 	if (strcmp(name, XATTR_NAME_SELINUX)) {
2222 		if (!strncmp(name, XATTR_SECURITY_PREFIX,
2223 			     sizeof XATTR_SECURITY_PREFIX - 1) &&
2224 		    !capable(CAP_SYS_ADMIN)) {
2225 			/* A different attribute in the security namespace.
2226 			   Restrict to administrator. */
2227 			return -EPERM;
2228 		}
2229 
2230 		/* Not an attribute we recognize, so just check the
2231 		   ordinary setattr permission. Might want a separate
2232 		   permission for removexattr. */
2233 		return dentry_has_perm(current, NULL, dentry, FILE__SETATTR);
2234 	}
2235 
2236 	/* No one is allowed to remove a SELinux security label.
2237 	   You can change the label, but all data must be labeled. */
2238 	return -EACCES;
2239 }
2240 
2241 /*
2242  * Copy the in-core inode security context value to the user.  If the
2243  * getxattr() prior to this succeeded, check to see if we need to
2244  * canonicalize the value to be finally returned to the user.
2245  *
2246  * Permission check is handled by selinux_inode_getxattr hook.
2247  */
2248 static int selinux_inode_getsecurity(struct inode *inode, const char *name, void *buffer, size_t size, int err)
2249 {
2250 	struct inode_security_struct *isec = inode->i_security;
2251 	char *context;
2252 	unsigned len;
2253 	int rc;
2254 
2255 	if (strcmp(name, XATTR_SELINUX_SUFFIX)) {
2256 		rc = -EOPNOTSUPP;
2257 		goto out;
2258 	}
2259 
2260 	rc = security_sid_to_context(isec->sid, &context, &len);
2261 	if (rc)
2262 		goto out;
2263 
2264 	/* Probe for required buffer size */
2265 	if (!buffer || !size) {
2266 		rc = len;
2267 		goto out_free;
2268 	}
2269 
2270 	if (size < len) {
2271 		rc = -ERANGE;
2272 		goto out_free;
2273 	}
2274 
2275 	if (err > 0) {
2276 		if ((len == err) && !(memcmp(context, buffer, len))) {
2277 			/* Don't need to canonicalize value */
2278 			rc = err;
2279 			goto out_free;
2280 		}
2281 		memset(buffer, 0, size);
2282 	}
2283 	memcpy(buffer, context, len);
2284 	rc = len;
2285 out_free:
2286 	kfree(context);
2287 out:
2288 	return rc;
2289 }
2290 
2291 static int selinux_inode_setsecurity(struct inode *inode, const char *name,
2292                                      const void *value, size_t size, int flags)
2293 {
2294 	struct inode_security_struct *isec = inode->i_security;
2295 	u32 newsid;
2296 	int rc;
2297 
2298 	if (strcmp(name, XATTR_SELINUX_SUFFIX))
2299 		return -EOPNOTSUPP;
2300 
2301 	if (!value || !size)
2302 		return -EACCES;
2303 
2304 	rc = security_context_to_sid((void*)value, size, &newsid);
2305 	if (rc)
2306 		return rc;
2307 
2308 	isec->sid = newsid;
2309 	return 0;
2310 }
2311 
2312 static int selinux_inode_listsecurity(struct inode *inode, char *buffer, size_t buffer_size)
2313 {
2314 	const int len = sizeof(XATTR_NAME_SELINUX);
2315 	if (buffer && len <= buffer_size)
2316 		memcpy(buffer, XATTR_NAME_SELINUX, len);
2317 	return len;
2318 }
2319 
2320 /* file security operations */
2321 
2322 static int selinux_file_permission(struct file *file, int mask)
2323 {
2324 	struct inode *inode = file->f_dentry->d_inode;
2325 
2326 	if (!mask) {
2327 		/* No permission to check.  Existence test. */
2328 		return 0;
2329 	}
2330 
2331 	/* file_mask_to_av won't add FILE__WRITE if MAY_APPEND is set */
2332 	if ((file->f_flags & O_APPEND) && (mask & MAY_WRITE))
2333 		mask |= MAY_APPEND;
2334 
2335 	return file_has_perm(current, file,
2336 			     file_mask_to_av(inode->i_mode, mask));
2337 }
2338 
2339 static int selinux_file_alloc_security(struct file *file)
2340 {
2341 	return file_alloc_security(file);
2342 }
2343 
2344 static void selinux_file_free_security(struct file *file)
2345 {
2346 	file_free_security(file);
2347 }
2348 
2349 static int selinux_file_ioctl(struct file *file, unsigned int cmd,
2350 			      unsigned long arg)
2351 {
2352 	int error = 0;
2353 
2354 	switch (cmd) {
2355 		case FIONREAD:
2356 		/* fall through */
2357 		case FIBMAP:
2358 		/* fall through */
2359 		case FIGETBSZ:
2360 		/* fall through */
2361 		case EXT2_IOC_GETFLAGS:
2362 		/* fall through */
2363 		case EXT2_IOC_GETVERSION:
2364 			error = file_has_perm(current, file, FILE__GETATTR);
2365 			break;
2366 
2367 		case EXT2_IOC_SETFLAGS:
2368 		/* fall through */
2369 		case EXT2_IOC_SETVERSION:
2370 			error = file_has_perm(current, file, FILE__SETATTR);
2371 			break;
2372 
2373 		/* sys_ioctl() checks */
2374 		case FIONBIO:
2375 		/* fall through */
2376 		case FIOASYNC:
2377 			error = file_has_perm(current, file, 0);
2378 			break;
2379 
2380 	        case KDSKBENT:
2381 	        case KDSKBSENT:
2382 			error = task_has_capability(current,CAP_SYS_TTY_CONFIG);
2383 			break;
2384 
2385 		/* default case assumes that the command will go
2386 		 * to the file's ioctl() function.
2387 		 */
2388 		default:
2389 			error = file_has_perm(current, file, FILE__IOCTL);
2390 
2391 	}
2392 	return error;
2393 }
2394 
2395 static int file_map_prot_check(struct file *file, unsigned long prot, int shared)
2396 {
2397 #ifndef CONFIG_PPC32
2398 	if ((prot & PROT_EXEC) && (!file || (!shared && (prot & PROT_WRITE)))) {
2399 		/*
2400 		 * We are making executable an anonymous mapping or a
2401 		 * private file mapping that will also be writable.
2402 		 * This has an additional check.
2403 		 */
2404 		int rc = task_has_perm(current, current, PROCESS__EXECMEM);
2405 		if (rc)
2406 			return rc;
2407 	}
2408 #endif
2409 
2410 	if (file) {
2411 		/* read access is always possible with a mapping */
2412 		u32 av = FILE__READ;
2413 
2414 		/* write access only matters if the mapping is shared */
2415 		if (shared && (prot & PROT_WRITE))
2416 			av |= FILE__WRITE;
2417 
2418 		if (prot & PROT_EXEC)
2419 			av |= FILE__EXECUTE;
2420 
2421 		return file_has_perm(current, file, av);
2422 	}
2423 	return 0;
2424 }
2425 
2426 static int selinux_file_mmap(struct file *file, unsigned long reqprot,
2427 			     unsigned long prot, unsigned long flags)
2428 {
2429 	int rc;
2430 
2431 	rc = secondary_ops->file_mmap(file, reqprot, prot, flags);
2432 	if (rc)
2433 		return rc;
2434 
2435 	if (selinux_checkreqprot)
2436 		prot = reqprot;
2437 
2438 	return file_map_prot_check(file, prot,
2439 				   (flags & MAP_TYPE) == MAP_SHARED);
2440 }
2441 
2442 static int selinux_file_mprotect(struct vm_area_struct *vma,
2443 				 unsigned long reqprot,
2444 				 unsigned long prot)
2445 {
2446 	int rc;
2447 
2448 	rc = secondary_ops->file_mprotect(vma, reqprot, prot);
2449 	if (rc)
2450 		return rc;
2451 
2452 	if (selinux_checkreqprot)
2453 		prot = reqprot;
2454 
2455 #ifndef CONFIG_PPC32
2456 	if ((prot & PROT_EXEC) && !(vma->vm_flags & VM_EXECUTABLE) &&
2457 	   (vma->vm_start >= vma->vm_mm->start_brk &&
2458 	    vma->vm_end <= vma->vm_mm->brk)) {
2459 	    	/*
2460 		 * We are making an executable mapping in the brk region.
2461 		 * This has an additional execheap check.
2462 		 */
2463 		rc = task_has_perm(current, current, PROCESS__EXECHEAP);
2464 		if (rc)
2465 			return rc;
2466 	}
2467 	if (vma->vm_file != NULL && vma->anon_vma != NULL && (prot & PROT_EXEC)) {
2468 		/*
2469 		 * We are making executable a file mapping that has
2470 		 * had some COW done. Since pages might have been written,
2471 		 * check ability to execute the possibly modified content.
2472 		 * This typically should only occur for text relocations.
2473 		 */
2474 		int rc = file_has_perm(current, vma->vm_file, FILE__EXECMOD);
2475 		if (rc)
2476 			return rc;
2477 	}
2478 	if (!vma->vm_file && (prot & PROT_EXEC) &&
2479 		vma->vm_start <= vma->vm_mm->start_stack &&
2480 		vma->vm_end >= vma->vm_mm->start_stack) {
2481 		/* Attempt to make the process stack executable.
2482 		 * This has an additional execstack check.
2483 		 */
2484 		rc = task_has_perm(current, current, PROCESS__EXECSTACK);
2485 		if (rc)
2486 			return rc;
2487 	}
2488 #endif
2489 
2490 	return file_map_prot_check(vma->vm_file, prot, vma->vm_flags&VM_SHARED);
2491 }
2492 
2493 static int selinux_file_lock(struct file *file, unsigned int cmd)
2494 {
2495 	return file_has_perm(current, file, FILE__LOCK);
2496 }
2497 
2498 static int selinux_file_fcntl(struct file *file, unsigned int cmd,
2499 			      unsigned long arg)
2500 {
2501 	int err = 0;
2502 
2503 	switch (cmd) {
2504 	        case F_SETFL:
2505 			if (!file->f_dentry || !file->f_dentry->d_inode) {
2506 				err = -EINVAL;
2507 				break;
2508 			}
2509 
2510 			if ((file->f_flags & O_APPEND) && !(arg & O_APPEND)) {
2511 				err = file_has_perm(current, file,FILE__WRITE);
2512 				break;
2513 			}
2514 			/* fall through */
2515 	        case F_SETOWN:
2516 	        case F_SETSIG:
2517 	        case F_GETFL:
2518 	        case F_GETOWN:
2519 	        case F_GETSIG:
2520 			/* Just check FD__USE permission */
2521 			err = file_has_perm(current, file, 0);
2522 			break;
2523 		case F_GETLK:
2524 		case F_SETLK:
2525 	        case F_SETLKW:
2526 #if BITS_PER_LONG == 32
2527 	        case F_GETLK64:
2528 		case F_SETLK64:
2529 	        case F_SETLKW64:
2530 #endif
2531 			if (!file->f_dentry || !file->f_dentry->d_inode) {
2532 				err = -EINVAL;
2533 				break;
2534 			}
2535 			err = file_has_perm(current, file, FILE__LOCK);
2536 			break;
2537 	}
2538 
2539 	return err;
2540 }
2541 
2542 static int selinux_file_set_fowner(struct file *file)
2543 {
2544 	struct task_security_struct *tsec;
2545 	struct file_security_struct *fsec;
2546 
2547 	tsec = current->security;
2548 	fsec = file->f_security;
2549 	fsec->fown_sid = tsec->sid;
2550 
2551 	return 0;
2552 }
2553 
2554 static int selinux_file_send_sigiotask(struct task_struct *tsk,
2555 				       struct fown_struct *fown, int signum)
2556 {
2557         struct file *file;
2558 	u32 perm;
2559 	struct task_security_struct *tsec;
2560 	struct file_security_struct *fsec;
2561 
2562 	/* struct fown_struct is never outside the context of a struct file */
2563         file = (struct file *)((long)fown - offsetof(struct file,f_owner));
2564 
2565 	tsec = tsk->security;
2566 	fsec = file->f_security;
2567 
2568 	if (!signum)
2569 		perm = signal_to_av(SIGIO); /* as per send_sigio_to_task */
2570 	else
2571 		perm = signal_to_av(signum);
2572 
2573 	return avc_has_perm(fsec->fown_sid, tsec->sid,
2574 			    SECCLASS_PROCESS, perm, NULL);
2575 }
2576 
2577 static int selinux_file_receive(struct file *file)
2578 {
2579 	return file_has_perm(current, file, file_to_av(file));
2580 }
2581 
2582 /* task security operations */
2583 
2584 static int selinux_task_create(unsigned long clone_flags)
2585 {
2586 	int rc;
2587 
2588 	rc = secondary_ops->task_create(clone_flags);
2589 	if (rc)
2590 		return rc;
2591 
2592 	return task_has_perm(current, current, PROCESS__FORK);
2593 }
2594 
2595 static int selinux_task_alloc_security(struct task_struct *tsk)
2596 {
2597 	struct task_security_struct *tsec1, *tsec2;
2598 	int rc;
2599 
2600 	tsec1 = current->security;
2601 
2602 	rc = task_alloc_security(tsk);
2603 	if (rc)
2604 		return rc;
2605 	tsec2 = tsk->security;
2606 
2607 	tsec2->osid = tsec1->osid;
2608 	tsec2->sid = tsec1->sid;
2609 
2610 	/* Retain the exec and create SIDs across fork */
2611 	tsec2->exec_sid = tsec1->exec_sid;
2612 	tsec2->create_sid = tsec1->create_sid;
2613 
2614 	/* Retain ptracer SID across fork, if any.
2615 	   This will be reset by the ptrace hook upon any
2616 	   subsequent ptrace_attach operations. */
2617 	tsec2->ptrace_sid = tsec1->ptrace_sid;
2618 
2619 	return 0;
2620 }
2621 
2622 static void selinux_task_free_security(struct task_struct *tsk)
2623 {
2624 	task_free_security(tsk);
2625 }
2626 
2627 static int selinux_task_setuid(uid_t id0, uid_t id1, uid_t id2, int flags)
2628 {
2629 	/* Since setuid only affects the current process, and
2630 	   since the SELinux controls are not based on the Linux
2631 	   identity attributes, SELinux does not need to control
2632 	   this operation.  However, SELinux does control the use
2633 	   of the CAP_SETUID and CAP_SETGID capabilities using the
2634 	   capable hook. */
2635 	return 0;
2636 }
2637 
2638 static int selinux_task_post_setuid(uid_t id0, uid_t id1, uid_t id2, int flags)
2639 {
2640 	return secondary_ops->task_post_setuid(id0,id1,id2,flags);
2641 }
2642 
2643 static int selinux_task_setgid(gid_t id0, gid_t id1, gid_t id2, int flags)
2644 {
2645 	/* See the comment for setuid above. */
2646 	return 0;
2647 }
2648 
2649 static int selinux_task_setpgid(struct task_struct *p, pid_t pgid)
2650 {
2651 	return task_has_perm(current, p, PROCESS__SETPGID);
2652 }
2653 
2654 static int selinux_task_getpgid(struct task_struct *p)
2655 {
2656 	return task_has_perm(current, p, PROCESS__GETPGID);
2657 }
2658 
2659 static int selinux_task_getsid(struct task_struct *p)
2660 {
2661 	return task_has_perm(current, p, PROCESS__GETSESSION);
2662 }
2663 
2664 static int selinux_task_setgroups(struct group_info *group_info)
2665 {
2666 	/* See the comment for setuid above. */
2667 	return 0;
2668 }
2669 
2670 static int selinux_task_setnice(struct task_struct *p, int nice)
2671 {
2672 	int rc;
2673 
2674 	rc = secondary_ops->task_setnice(p, nice);
2675 	if (rc)
2676 		return rc;
2677 
2678 	return task_has_perm(current,p, PROCESS__SETSCHED);
2679 }
2680 
2681 static int selinux_task_setrlimit(unsigned int resource, struct rlimit *new_rlim)
2682 {
2683 	struct rlimit *old_rlim = current->signal->rlim + resource;
2684 	int rc;
2685 
2686 	rc = secondary_ops->task_setrlimit(resource, new_rlim);
2687 	if (rc)
2688 		return rc;
2689 
2690 	/* Control the ability to change the hard limit (whether
2691 	   lowering or raising it), so that the hard limit can
2692 	   later be used as a safe reset point for the soft limit
2693 	   upon context transitions. See selinux_bprm_apply_creds. */
2694 	if (old_rlim->rlim_max != new_rlim->rlim_max)
2695 		return task_has_perm(current, current, PROCESS__SETRLIMIT);
2696 
2697 	return 0;
2698 }
2699 
2700 static int selinux_task_setscheduler(struct task_struct *p, int policy, struct sched_param *lp)
2701 {
2702 	return task_has_perm(current, p, PROCESS__SETSCHED);
2703 }
2704 
2705 static int selinux_task_getscheduler(struct task_struct *p)
2706 {
2707 	return task_has_perm(current, p, PROCESS__GETSCHED);
2708 }
2709 
2710 static int selinux_task_kill(struct task_struct *p, struct siginfo *info, int sig)
2711 {
2712 	u32 perm;
2713 	int rc;
2714 
2715 	rc = secondary_ops->task_kill(p, info, sig);
2716 	if (rc)
2717 		return rc;
2718 
2719 	if (info != SEND_SIG_NOINFO && (is_si_special(info) || SI_FROMKERNEL(info)))
2720 		return 0;
2721 
2722 	if (!sig)
2723 		perm = PROCESS__SIGNULL; /* null signal; existence test */
2724 	else
2725 		perm = signal_to_av(sig);
2726 
2727 	return task_has_perm(current, p, perm);
2728 }
2729 
2730 static int selinux_task_prctl(int option,
2731 			      unsigned long arg2,
2732 			      unsigned long arg3,
2733 			      unsigned long arg4,
2734 			      unsigned long arg5)
2735 {
2736 	/* The current prctl operations do not appear to require
2737 	   any SELinux controls since they merely observe or modify
2738 	   the state of the current process. */
2739 	return 0;
2740 }
2741 
2742 static int selinux_task_wait(struct task_struct *p)
2743 {
2744 	u32 perm;
2745 
2746 	perm = signal_to_av(p->exit_signal);
2747 
2748 	return task_has_perm(p, current, perm);
2749 }
2750 
2751 static void selinux_task_reparent_to_init(struct task_struct *p)
2752 {
2753   	struct task_security_struct *tsec;
2754 
2755 	secondary_ops->task_reparent_to_init(p);
2756 
2757 	tsec = p->security;
2758 	tsec->osid = tsec->sid;
2759 	tsec->sid = SECINITSID_KERNEL;
2760 	return;
2761 }
2762 
2763 static void selinux_task_to_inode(struct task_struct *p,
2764 				  struct inode *inode)
2765 {
2766 	struct task_security_struct *tsec = p->security;
2767 	struct inode_security_struct *isec = inode->i_security;
2768 
2769 	isec->sid = tsec->sid;
2770 	isec->initialized = 1;
2771 	return;
2772 }
2773 
2774 #ifdef CONFIG_SECURITY_NETWORK
2775 
2776 /* Returns error only if unable to parse addresses */
2777 static int selinux_parse_skb_ipv4(struct sk_buff *skb, struct avc_audit_data *ad)
2778 {
2779 	int offset, ihlen, ret = -EINVAL;
2780 	struct iphdr _iph, *ih;
2781 
2782 	offset = skb->nh.raw - skb->data;
2783 	ih = skb_header_pointer(skb, offset, sizeof(_iph), &_iph);
2784 	if (ih == NULL)
2785 		goto out;
2786 
2787 	ihlen = ih->ihl * 4;
2788 	if (ihlen < sizeof(_iph))
2789 		goto out;
2790 
2791 	ad->u.net.v4info.saddr = ih->saddr;
2792 	ad->u.net.v4info.daddr = ih->daddr;
2793 	ret = 0;
2794 
2795 	switch (ih->protocol) {
2796         case IPPROTO_TCP: {
2797         	struct tcphdr _tcph, *th;
2798 
2799         	if (ntohs(ih->frag_off) & IP_OFFSET)
2800         		break;
2801 
2802 		offset += ihlen;
2803 		th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph);
2804 		if (th == NULL)
2805 			break;
2806 
2807 		ad->u.net.sport = th->source;
2808 		ad->u.net.dport = th->dest;
2809 		break;
2810         }
2811 
2812         case IPPROTO_UDP: {
2813         	struct udphdr _udph, *uh;
2814 
2815         	if (ntohs(ih->frag_off) & IP_OFFSET)
2816         		break;
2817 
2818 		offset += ihlen;
2819         	uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph);
2820 		if (uh == NULL)
2821 			break;
2822 
2823         	ad->u.net.sport = uh->source;
2824         	ad->u.net.dport = uh->dest;
2825         	break;
2826         }
2827 
2828         default:
2829         	break;
2830         }
2831 out:
2832 	return ret;
2833 }
2834 
2835 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
2836 
2837 /* Returns error only if unable to parse addresses */
2838 static int selinux_parse_skb_ipv6(struct sk_buff *skb, struct avc_audit_data *ad)
2839 {
2840 	u8 nexthdr;
2841 	int ret = -EINVAL, offset;
2842 	struct ipv6hdr _ipv6h, *ip6;
2843 
2844 	offset = skb->nh.raw - skb->data;
2845 	ip6 = skb_header_pointer(skb, offset, sizeof(_ipv6h), &_ipv6h);
2846 	if (ip6 == NULL)
2847 		goto out;
2848 
2849 	ipv6_addr_copy(&ad->u.net.v6info.saddr, &ip6->saddr);
2850 	ipv6_addr_copy(&ad->u.net.v6info.daddr, &ip6->daddr);
2851 	ret = 0;
2852 
2853 	nexthdr = ip6->nexthdr;
2854 	offset += sizeof(_ipv6h);
2855 	offset = ipv6_skip_exthdr(skb, offset, &nexthdr);
2856 	if (offset < 0)
2857 		goto out;
2858 
2859 	switch (nexthdr) {
2860 	case IPPROTO_TCP: {
2861         	struct tcphdr _tcph, *th;
2862 
2863 		th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph);
2864 		if (th == NULL)
2865 			break;
2866 
2867 		ad->u.net.sport = th->source;
2868 		ad->u.net.dport = th->dest;
2869 		break;
2870 	}
2871 
2872 	case IPPROTO_UDP: {
2873 		struct udphdr _udph, *uh;
2874 
2875 		uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph);
2876 		if (uh == NULL)
2877 			break;
2878 
2879 		ad->u.net.sport = uh->source;
2880 		ad->u.net.dport = uh->dest;
2881 		break;
2882 	}
2883 
2884 	/* includes fragments */
2885 	default:
2886 		break;
2887 	}
2888 out:
2889 	return ret;
2890 }
2891 
2892 #endif /* IPV6 */
2893 
2894 static int selinux_parse_skb(struct sk_buff *skb, struct avc_audit_data *ad,
2895 			     char **addrp, int *len, int src)
2896 {
2897 	int ret = 0;
2898 
2899 	switch (ad->u.net.family) {
2900 	case PF_INET:
2901 		ret = selinux_parse_skb_ipv4(skb, ad);
2902 		if (ret || !addrp)
2903 			break;
2904 		*len = 4;
2905 		*addrp = (char *)(src ? &ad->u.net.v4info.saddr :
2906 					&ad->u.net.v4info.daddr);
2907 		break;
2908 
2909 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
2910 	case PF_INET6:
2911 		ret = selinux_parse_skb_ipv6(skb, ad);
2912 		if (ret || !addrp)
2913 			break;
2914 		*len = 16;
2915 		*addrp = (char *)(src ? &ad->u.net.v6info.saddr :
2916 					&ad->u.net.v6info.daddr);
2917 		break;
2918 #endif	/* IPV6 */
2919 	default:
2920 		break;
2921 	}
2922 
2923 	return ret;
2924 }
2925 
2926 /* socket security operations */
2927 static int socket_has_perm(struct task_struct *task, struct socket *sock,
2928 			   u32 perms)
2929 {
2930 	struct inode_security_struct *isec;
2931 	struct task_security_struct *tsec;
2932 	struct avc_audit_data ad;
2933 	int err = 0;
2934 
2935 	tsec = task->security;
2936 	isec = SOCK_INODE(sock)->i_security;
2937 
2938 	if (isec->sid == SECINITSID_KERNEL)
2939 		goto out;
2940 
2941 	AVC_AUDIT_DATA_INIT(&ad,NET);
2942 	ad.u.net.sk = sock->sk;
2943 	err = avc_has_perm(tsec->sid, isec->sid, isec->sclass, perms, &ad);
2944 
2945 out:
2946 	return err;
2947 }
2948 
2949 static int selinux_socket_create(int family, int type,
2950 				 int protocol, int kern)
2951 {
2952 	int err = 0;
2953 	struct task_security_struct *tsec;
2954 
2955 	if (kern)
2956 		goto out;
2957 
2958 	tsec = current->security;
2959 	err = avc_has_perm(tsec->sid, tsec->sid,
2960 			   socket_type_to_security_class(family, type,
2961 			   protocol), SOCKET__CREATE, NULL);
2962 
2963 out:
2964 	return err;
2965 }
2966 
2967 static void selinux_socket_post_create(struct socket *sock, int family,
2968 				       int type, int protocol, int kern)
2969 {
2970 	struct inode_security_struct *isec;
2971 	struct task_security_struct *tsec;
2972 
2973 	isec = SOCK_INODE(sock)->i_security;
2974 
2975 	tsec = current->security;
2976 	isec->sclass = socket_type_to_security_class(family, type, protocol);
2977 	isec->sid = kern ? SECINITSID_KERNEL : tsec->sid;
2978 	isec->initialized = 1;
2979 
2980 	return;
2981 }
2982 
2983 /* Range of port numbers used to automatically bind.
2984    Need to determine whether we should perform a name_bind
2985    permission check between the socket and the port number. */
2986 #define ip_local_port_range_0 sysctl_local_port_range[0]
2987 #define ip_local_port_range_1 sysctl_local_port_range[1]
2988 
2989 static int selinux_socket_bind(struct socket *sock, struct sockaddr *address, int addrlen)
2990 {
2991 	u16 family;
2992 	int err;
2993 
2994 	err = socket_has_perm(current, sock, SOCKET__BIND);
2995 	if (err)
2996 		goto out;
2997 
2998 	/*
2999 	 * If PF_INET or PF_INET6, check name_bind permission for the port.
3000 	 * Multiple address binding for SCTP is not supported yet: we just
3001 	 * check the first address now.
3002 	 */
3003 	family = sock->sk->sk_family;
3004 	if (family == PF_INET || family == PF_INET6) {
3005 		char *addrp;
3006 		struct inode_security_struct *isec;
3007 		struct task_security_struct *tsec;
3008 		struct avc_audit_data ad;
3009 		struct sockaddr_in *addr4 = NULL;
3010 		struct sockaddr_in6 *addr6 = NULL;
3011 		unsigned short snum;
3012 		struct sock *sk = sock->sk;
3013 		u32 sid, node_perm, addrlen;
3014 
3015 		tsec = current->security;
3016 		isec = SOCK_INODE(sock)->i_security;
3017 
3018 		if (family == PF_INET) {
3019 			addr4 = (struct sockaddr_in *)address;
3020 			snum = ntohs(addr4->sin_port);
3021 			addrlen = sizeof(addr4->sin_addr.s_addr);
3022 			addrp = (char *)&addr4->sin_addr.s_addr;
3023 		} else {
3024 			addr6 = (struct sockaddr_in6 *)address;
3025 			snum = ntohs(addr6->sin6_port);
3026 			addrlen = sizeof(addr6->sin6_addr.s6_addr);
3027 			addrp = (char *)&addr6->sin6_addr.s6_addr;
3028 		}
3029 
3030 		if (snum&&(snum < max(PROT_SOCK,ip_local_port_range_0) ||
3031 			   snum > ip_local_port_range_1)) {
3032 			err = security_port_sid(sk->sk_family, sk->sk_type,
3033 						sk->sk_protocol, snum, &sid);
3034 			if (err)
3035 				goto out;
3036 			AVC_AUDIT_DATA_INIT(&ad,NET);
3037 			ad.u.net.sport = htons(snum);
3038 			ad.u.net.family = family;
3039 			err = avc_has_perm(isec->sid, sid,
3040 					   isec->sclass,
3041 					   SOCKET__NAME_BIND, &ad);
3042 			if (err)
3043 				goto out;
3044 		}
3045 
3046 		switch(isec->sclass) {
3047 		case SECCLASS_TCP_SOCKET:
3048 			node_perm = TCP_SOCKET__NODE_BIND;
3049 			break;
3050 
3051 		case SECCLASS_UDP_SOCKET:
3052 			node_perm = UDP_SOCKET__NODE_BIND;
3053 			break;
3054 
3055 		default:
3056 			node_perm = RAWIP_SOCKET__NODE_BIND;
3057 			break;
3058 		}
3059 
3060 		err = security_node_sid(family, addrp, addrlen, &sid);
3061 		if (err)
3062 			goto out;
3063 
3064 		AVC_AUDIT_DATA_INIT(&ad,NET);
3065 		ad.u.net.sport = htons(snum);
3066 		ad.u.net.family = family;
3067 
3068 		if (family == PF_INET)
3069 			ad.u.net.v4info.saddr = addr4->sin_addr.s_addr;
3070 		else
3071 			ipv6_addr_copy(&ad.u.net.v6info.saddr, &addr6->sin6_addr);
3072 
3073 		err = avc_has_perm(isec->sid, sid,
3074 		                   isec->sclass, node_perm, &ad);
3075 		if (err)
3076 			goto out;
3077 	}
3078 out:
3079 	return err;
3080 }
3081 
3082 static int selinux_socket_connect(struct socket *sock, struct sockaddr *address, int addrlen)
3083 {
3084 	struct inode_security_struct *isec;
3085 	int err;
3086 
3087 	err = socket_has_perm(current, sock, SOCKET__CONNECT);
3088 	if (err)
3089 		return err;
3090 
3091 	/*
3092 	 * If a TCP socket, check name_connect permission for the port.
3093 	 */
3094 	isec = SOCK_INODE(sock)->i_security;
3095 	if (isec->sclass == SECCLASS_TCP_SOCKET) {
3096 		struct sock *sk = sock->sk;
3097 		struct avc_audit_data ad;
3098 		struct sockaddr_in *addr4 = NULL;
3099 		struct sockaddr_in6 *addr6 = NULL;
3100 		unsigned short snum;
3101 		u32 sid;
3102 
3103 		if (sk->sk_family == PF_INET) {
3104 			addr4 = (struct sockaddr_in *)address;
3105 			if (addrlen < sizeof(struct sockaddr_in))
3106 				return -EINVAL;
3107 			snum = ntohs(addr4->sin_port);
3108 		} else {
3109 			addr6 = (struct sockaddr_in6 *)address;
3110 			if (addrlen < SIN6_LEN_RFC2133)
3111 				return -EINVAL;
3112 			snum = ntohs(addr6->sin6_port);
3113 		}
3114 
3115 		err = security_port_sid(sk->sk_family, sk->sk_type,
3116 					sk->sk_protocol, snum, &sid);
3117 		if (err)
3118 			goto out;
3119 
3120 		AVC_AUDIT_DATA_INIT(&ad,NET);
3121 		ad.u.net.dport = htons(snum);
3122 		ad.u.net.family = sk->sk_family;
3123 		err = avc_has_perm(isec->sid, sid, isec->sclass,
3124 				   TCP_SOCKET__NAME_CONNECT, &ad);
3125 		if (err)
3126 			goto out;
3127 	}
3128 
3129 out:
3130 	return err;
3131 }
3132 
3133 static int selinux_socket_listen(struct socket *sock, int backlog)
3134 {
3135 	return socket_has_perm(current, sock, SOCKET__LISTEN);
3136 }
3137 
3138 static int selinux_socket_accept(struct socket *sock, struct socket *newsock)
3139 {
3140 	int err;
3141 	struct inode_security_struct *isec;
3142 	struct inode_security_struct *newisec;
3143 
3144 	err = socket_has_perm(current, sock, SOCKET__ACCEPT);
3145 	if (err)
3146 		return err;
3147 
3148 	newisec = SOCK_INODE(newsock)->i_security;
3149 
3150 	isec = SOCK_INODE(sock)->i_security;
3151 	newisec->sclass = isec->sclass;
3152 	newisec->sid = isec->sid;
3153 	newisec->initialized = 1;
3154 
3155 	return 0;
3156 }
3157 
3158 static int selinux_socket_sendmsg(struct socket *sock, struct msghdr *msg,
3159  				  int size)
3160 {
3161 	return socket_has_perm(current, sock, SOCKET__WRITE);
3162 }
3163 
3164 static int selinux_socket_recvmsg(struct socket *sock, struct msghdr *msg,
3165 				  int size, int flags)
3166 {
3167 	return socket_has_perm(current, sock, SOCKET__READ);
3168 }
3169 
3170 static int selinux_socket_getsockname(struct socket *sock)
3171 {
3172 	return socket_has_perm(current, sock, SOCKET__GETATTR);
3173 }
3174 
3175 static int selinux_socket_getpeername(struct socket *sock)
3176 {
3177 	return socket_has_perm(current, sock, SOCKET__GETATTR);
3178 }
3179 
3180 static int selinux_socket_setsockopt(struct socket *sock,int level,int optname)
3181 {
3182 	return socket_has_perm(current, sock, SOCKET__SETOPT);
3183 }
3184 
3185 static int selinux_socket_getsockopt(struct socket *sock, int level,
3186 				     int optname)
3187 {
3188 	return socket_has_perm(current, sock, SOCKET__GETOPT);
3189 }
3190 
3191 static int selinux_socket_shutdown(struct socket *sock, int how)
3192 {
3193 	return socket_has_perm(current, sock, SOCKET__SHUTDOWN);
3194 }
3195 
3196 static int selinux_socket_unix_stream_connect(struct socket *sock,
3197 					      struct socket *other,
3198 					      struct sock *newsk)
3199 {
3200 	struct sk_security_struct *ssec;
3201 	struct inode_security_struct *isec;
3202 	struct inode_security_struct *other_isec;
3203 	struct avc_audit_data ad;
3204 	int err;
3205 
3206 	err = secondary_ops->unix_stream_connect(sock, other, newsk);
3207 	if (err)
3208 		return err;
3209 
3210 	isec = SOCK_INODE(sock)->i_security;
3211 	other_isec = SOCK_INODE(other)->i_security;
3212 
3213 	AVC_AUDIT_DATA_INIT(&ad,NET);
3214 	ad.u.net.sk = other->sk;
3215 
3216 	err = avc_has_perm(isec->sid, other_isec->sid,
3217 			   isec->sclass,
3218 			   UNIX_STREAM_SOCKET__CONNECTTO, &ad);
3219 	if (err)
3220 		return err;
3221 
3222 	/* connecting socket */
3223 	ssec = sock->sk->sk_security;
3224 	ssec->peer_sid = other_isec->sid;
3225 
3226 	/* server child socket */
3227 	ssec = newsk->sk_security;
3228 	ssec->peer_sid = isec->sid;
3229 
3230 	return 0;
3231 }
3232 
3233 static int selinux_socket_unix_may_send(struct socket *sock,
3234 					struct socket *other)
3235 {
3236 	struct inode_security_struct *isec;
3237 	struct inode_security_struct *other_isec;
3238 	struct avc_audit_data ad;
3239 	int err;
3240 
3241 	isec = SOCK_INODE(sock)->i_security;
3242 	other_isec = SOCK_INODE(other)->i_security;
3243 
3244 	AVC_AUDIT_DATA_INIT(&ad,NET);
3245 	ad.u.net.sk = other->sk;
3246 
3247 	err = avc_has_perm(isec->sid, other_isec->sid,
3248 			   isec->sclass, SOCKET__SENDTO, &ad);
3249 	if (err)
3250 		return err;
3251 
3252 	return 0;
3253 }
3254 
3255 static int selinux_socket_sock_rcv_skb(struct sock *sk, struct sk_buff *skb)
3256 {
3257 	u16 family;
3258 	char *addrp;
3259 	int len, err = 0;
3260 	u32 netif_perm, node_perm, node_sid, if_sid, recv_perm = 0;
3261 	u32 sock_sid = 0;
3262 	u16 sock_class = 0;
3263 	struct socket *sock;
3264 	struct net_device *dev;
3265 	struct avc_audit_data ad;
3266 
3267 	family = sk->sk_family;
3268 	if (family != PF_INET && family != PF_INET6)
3269 		goto out;
3270 
3271 	/* Handle mapped IPv4 packets arriving via IPv6 sockets */
3272 	if (family == PF_INET6 && skb->protocol == ntohs(ETH_P_IP))
3273 		family = PF_INET;
3274 
3275  	read_lock_bh(&sk->sk_callback_lock);
3276  	sock = sk->sk_socket;
3277  	if (sock) {
3278  		struct inode *inode;
3279  		inode = SOCK_INODE(sock);
3280  		if (inode) {
3281  			struct inode_security_struct *isec;
3282  			isec = inode->i_security;
3283  			sock_sid = isec->sid;
3284  			sock_class = isec->sclass;
3285  		}
3286  	}
3287  	read_unlock_bh(&sk->sk_callback_lock);
3288  	if (!sock_sid)
3289   		goto out;
3290 
3291 	dev = skb->dev;
3292 	if (!dev)
3293 		goto out;
3294 
3295 	err = sel_netif_sids(dev, &if_sid, NULL);
3296 	if (err)
3297 		goto out;
3298 
3299 	switch (sock_class) {
3300 	case SECCLASS_UDP_SOCKET:
3301 		netif_perm = NETIF__UDP_RECV;
3302 		node_perm = NODE__UDP_RECV;
3303 		recv_perm = UDP_SOCKET__RECV_MSG;
3304 		break;
3305 
3306 	case SECCLASS_TCP_SOCKET:
3307 		netif_perm = NETIF__TCP_RECV;
3308 		node_perm = NODE__TCP_RECV;
3309 		recv_perm = TCP_SOCKET__RECV_MSG;
3310 		break;
3311 
3312 	default:
3313 		netif_perm = NETIF__RAWIP_RECV;
3314 		node_perm = NODE__RAWIP_RECV;
3315 		break;
3316 	}
3317 
3318 	AVC_AUDIT_DATA_INIT(&ad, NET);
3319 	ad.u.net.netif = dev->name;
3320 	ad.u.net.family = family;
3321 
3322 	err = selinux_parse_skb(skb, &ad, &addrp, &len, 1);
3323 	if (err)
3324 		goto out;
3325 
3326 	err = avc_has_perm(sock_sid, if_sid, SECCLASS_NETIF, netif_perm, &ad);
3327 	if (err)
3328 		goto out;
3329 
3330 	/* Fixme: this lookup is inefficient */
3331 	err = security_node_sid(family, addrp, len, &node_sid);
3332 	if (err)
3333 		goto out;
3334 
3335 	err = avc_has_perm(sock_sid, node_sid, SECCLASS_NODE, node_perm, &ad);
3336 	if (err)
3337 		goto out;
3338 
3339 	if (recv_perm) {
3340 		u32 port_sid;
3341 
3342 		/* Fixme: make this more efficient */
3343 		err = security_port_sid(sk->sk_family, sk->sk_type,
3344 		                        sk->sk_protocol, ntohs(ad.u.net.sport),
3345 		                        &port_sid);
3346 		if (err)
3347 			goto out;
3348 
3349 		err = avc_has_perm(sock_sid, port_sid,
3350 				   sock_class, recv_perm, &ad);
3351 	}
3352 out:
3353 	return err;
3354 }
3355 
3356 static int selinux_socket_getpeersec(struct socket *sock, char __user *optval,
3357 				     int __user *optlen, unsigned len)
3358 {
3359 	int err = 0;
3360 	char *scontext;
3361 	u32 scontext_len;
3362 	struct sk_security_struct *ssec;
3363 	struct inode_security_struct *isec;
3364 
3365 	isec = SOCK_INODE(sock)->i_security;
3366 	if (isec->sclass != SECCLASS_UNIX_STREAM_SOCKET) {
3367 		err = -ENOPROTOOPT;
3368 		goto out;
3369 	}
3370 
3371 	ssec = sock->sk->sk_security;
3372 
3373 	err = security_sid_to_context(ssec->peer_sid, &scontext, &scontext_len);
3374 	if (err)
3375 		goto out;
3376 
3377 	if (scontext_len > len) {
3378 		err = -ERANGE;
3379 		goto out_len;
3380 	}
3381 
3382 	if (copy_to_user(optval, scontext, scontext_len))
3383 		err = -EFAULT;
3384 
3385 out_len:
3386 	if (put_user(scontext_len, optlen))
3387 		err = -EFAULT;
3388 
3389 	kfree(scontext);
3390 out:
3391 	return err;
3392 }
3393 
3394 static int selinux_sk_alloc_security(struct sock *sk, int family, gfp_t priority)
3395 {
3396 	return sk_alloc_security(sk, family, priority);
3397 }
3398 
3399 static void selinux_sk_free_security(struct sock *sk)
3400 {
3401 	sk_free_security(sk);
3402 }
3403 
3404 static int selinux_nlmsg_perm(struct sock *sk, struct sk_buff *skb)
3405 {
3406 	int err = 0;
3407 	u32 perm;
3408 	struct nlmsghdr *nlh;
3409 	struct socket *sock = sk->sk_socket;
3410 	struct inode_security_struct *isec = SOCK_INODE(sock)->i_security;
3411 
3412 	if (skb->len < NLMSG_SPACE(0)) {
3413 		err = -EINVAL;
3414 		goto out;
3415 	}
3416 	nlh = (struct nlmsghdr *)skb->data;
3417 
3418 	err = selinux_nlmsg_lookup(isec->sclass, nlh->nlmsg_type, &perm);
3419 	if (err) {
3420 		if (err == -EINVAL) {
3421 			audit_log(current->audit_context, GFP_KERNEL, AUDIT_SELINUX_ERR,
3422 				  "SELinux:  unrecognized netlink message"
3423 				  " type=%hu for sclass=%hu\n",
3424 				  nlh->nlmsg_type, isec->sclass);
3425 			if (!selinux_enforcing)
3426 				err = 0;
3427 		}
3428 
3429 		/* Ignore */
3430 		if (err == -ENOENT)
3431 			err = 0;
3432 		goto out;
3433 	}
3434 
3435 	err = socket_has_perm(current, sock, perm);
3436 out:
3437 	return err;
3438 }
3439 
3440 #ifdef CONFIG_NETFILTER
3441 
3442 static unsigned int selinux_ip_postroute_last(unsigned int hooknum,
3443                                               struct sk_buff **pskb,
3444                                               const struct net_device *in,
3445                                               const struct net_device *out,
3446                                               int (*okfn)(struct sk_buff *),
3447                                               u16 family)
3448 {
3449 	char *addrp;
3450 	int len, err = NF_ACCEPT;
3451 	u32 netif_perm, node_perm, node_sid, if_sid, send_perm = 0;
3452 	struct sock *sk;
3453 	struct socket *sock;
3454 	struct inode *inode;
3455 	struct sk_buff *skb = *pskb;
3456 	struct inode_security_struct *isec;
3457 	struct avc_audit_data ad;
3458 	struct net_device *dev = (struct net_device *)out;
3459 
3460 	sk = skb->sk;
3461 	if (!sk)
3462 		goto out;
3463 
3464 	sock = sk->sk_socket;
3465 	if (!sock)
3466 		goto out;
3467 
3468 	inode = SOCK_INODE(sock);
3469 	if (!inode)
3470 		goto out;
3471 
3472 	err = sel_netif_sids(dev, &if_sid, NULL);
3473 	if (err)
3474 		goto out;
3475 
3476 	isec = inode->i_security;
3477 
3478 	switch (isec->sclass) {
3479 	case SECCLASS_UDP_SOCKET:
3480 		netif_perm = NETIF__UDP_SEND;
3481 		node_perm = NODE__UDP_SEND;
3482 		send_perm = UDP_SOCKET__SEND_MSG;
3483 		break;
3484 
3485 	case SECCLASS_TCP_SOCKET:
3486 		netif_perm = NETIF__TCP_SEND;
3487 		node_perm = NODE__TCP_SEND;
3488 		send_perm = TCP_SOCKET__SEND_MSG;
3489 		break;
3490 
3491 	default:
3492 		netif_perm = NETIF__RAWIP_SEND;
3493 		node_perm = NODE__RAWIP_SEND;
3494 		break;
3495 	}
3496 
3497 
3498 	AVC_AUDIT_DATA_INIT(&ad, NET);
3499 	ad.u.net.netif = dev->name;
3500 	ad.u.net.family = family;
3501 
3502 	err = selinux_parse_skb(skb, &ad, &addrp,
3503 				&len, 0) ? NF_DROP : NF_ACCEPT;
3504 	if (err != NF_ACCEPT)
3505 		goto out;
3506 
3507 	err = avc_has_perm(isec->sid, if_sid, SECCLASS_NETIF,
3508 	                   netif_perm, &ad) ? NF_DROP : NF_ACCEPT;
3509 	if (err != NF_ACCEPT)
3510 		goto out;
3511 
3512 	/* Fixme: this lookup is inefficient */
3513 	err = security_node_sid(family, addrp, len,
3514 				&node_sid) ? NF_DROP : NF_ACCEPT;
3515 	if (err != NF_ACCEPT)
3516 		goto out;
3517 
3518 	err = avc_has_perm(isec->sid, node_sid, SECCLASS_NODE,
3519 	                   node_perm, &ad) ? NF_DROP : NF_ACCEPT;
3520 	if (err != NF_ACCEPT)
3521 		goto out;
3522 
3523 	if (send_perm) {
3524 		u32 port_sid;
3525 
3526 		/* Fixme: make this more efficient */
3527 		err = security_port_sid(sk->sk_family,
3528 		                        sk->sk_type,
3529 		                        sk->sk_protocol,
3530 		                        ntohs(ad.u.net.dport),
3531 		                        &port_sid) ? NF_DROP : NF_ACCEPT;
3532 		if (err != NF_ACCEPT)
3533 			goto out;
3534 
3535 		err = avc_has_perm(isec->sid, port_sid, isec->sclass,
3536 		                   send_perm, &ad) ? NF_DROP : NF_ACCEPT;
3537 	}
3538 
3539 out:
3540 	return err;
3541 }
3542 
3543 static unsigned int selinux_ipv4_postroute_last(unsigned int hooknum,
3544 						struct sk_buff **pskb,
3545 						const struct net_device *in,
3546 						const struct net_device *out,
3547 						int (*okfn)(struct sk_buff *))
3548 {
3549 	return selinux_ip_postroute_last(hooknum, pskb, in, out, okfn, PF_INET);
3550 }
3551 
3552 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
3553 
3554 static unsigned int selinux_ipv6_postroute_last(unsigned int hooknum,
3555 						struct sk_buff **pskb,
3556 						const struct net_device *in,
3557 						const struct net_device *out,
3558 						int (*okfn)(struct sk_buff *))
3559 {
3560 	return selinux_ip_postroute_last(hooknum, pskb, in, out, okfn, PF_INET6);
3561 }
3562 
3563 #endif	/* IPV6 */
3564 
3565 #endif	/* CONFIG_NETFILTER */
3566 
3567 #else
3568 
3569 static inline int selinux_nlmsg_perm(struct sock *sk, struct sk_buff *skb)
3570 {
3571 	return 0;
3572 }
3573 
3574 #endif	/* CONFIG_SECURITY_NETWORK */
3575 
3576 static int selinux_netlink_send(struct sock *sk, struct sk_buff *skb)
3577 {
3578 	struct task_security_struct *tsec;
3579 	struct av_decision avd;
3580 	int err;
3581 
3582 	err = secondary_ops->netlink_send(sk, skb);
3583 	if (err)
3584 		return err;
3585 
3586 	tsec = current->security;
3587 
3588 	avd.allowed = 0;
3589 	avc_has_perm_noaudit(tsec->sid, tsec->sid,
3590 				SECCLASS_CAPABILITY, ~0, &avd);
3591 	cap_mask(NETLINK_CB(skb).eff_cap, avd.allowed);
3592 
3593 	if (policydb_loaded_version >= POLICYDB_VERSION_NLCLASS)
3594 		err = selinux_nlmsg_perm(sk, skb);
3595 
3596 	return err;
3597 }
3598 
3599 static int selinux_netlink_recv(struct sk_buff *skb)
3600 {
3601 	if (!cap_raised(NETLINK_CB(skb).eff_cap, CAP_NET_ADMIN))
3602 		return -EPERM;
3603 	return 0;
3604 }
3605 
3606 static int ipc_alloc_security(struct task_struct *task,
3607 			      struct kern_ipc_perm *perm,
3608 			      u16 sclass)
3609 {
3610 	struct task_security_struct *tsec = task->security;
3611 	struct ipc_security_struct *isec;
3612 
3613 	isec = kzalloc(sizeof(struct ipc_security_struct), GFP_KERNEL);
3614 	if (!isec)
3615 		return -ENOMEM;
3616 
3617 	isec->magic = SELINUX_MAGIC;
3618 	isec->sclass = sclass;
3619 	isec->ipc_perm = perm;
3620 	if (tsec) {
3621 		isec->sid = tsec->sid;
3622 	} else {
3623 		isec->sid = SECINITSID_UNLABELED;
3624 	}
3625 	perm->security = isec;
3626 
3627 	return 0;
3628 }
3629 
3630 static void ipc_free_security(struct kern_ipc_perm *perm)
3631 {
3632 	struct ipc_security_struct *isec = perm->security;
3633 	if (!isec || isec->magic != SELINUX_MAGIC)
3634 		return;
3635 
3636 	perm->security = NULL;
3637 	kfree(isec);
3638 }
3639 
3640 static int msg_msg_alloc_security(struct msg_msg *msg)
3641 {
3642 	struct msg_security_struct *msec;
3643 
3644 	msec = kzalloc(sizeof(struct msg_security_struct), GFP_KERNEL);
3645 	if (!msec)
3646 		return -ENOMEM;
3647 
3648 	msec->magic = SELINUX_MAGIC;
3649 	msec->msg = msg;
3650 	msec->sid = SECINITSID_UNLABELED;
3651 	msg->security = msec;
3652 
3653 	return 0;
3654 }
3655 
3656 static void msg_msg_free_security(struct msg_msg *msg)
3657 {
3658 	struct msg_security_struct *msec = msg->security;
3659 	if (!msec || msec->magic != SELINUX_MAGIC)
3660 		return;
3661 
3662 	msg->security = NULL;
3663 	kfree(msec);
3664 }
3665 
3666 static int ipc_has_perm(struct kern_ipc_perm *ipc_perms,
3667 			u32 perms)
3668 {
3669 	struct task_security_struct *tsec;
3670 	struct ipc_security_struct *isec;
3671 	struct avc_audit_data ad;
3672 
3673 	tsec = current->security;
3674 	isec = ipc_perms->security;
3675 
3676 	AVC_AUDIT_DATA_INIT(&ad, IPC);
3677 	ad.u.ipc_id = ipc_perms->key;
3678 
3679 	return avc_has_perm(tsec->sid, isec->sid, isec->sclass, perms, &ad);
3680 }
3681 
3682 static int selinux_msg_msg_alloc_security(struct msg_msg *msg)
3683 {
3684 	return msg_msg_alloc_security(msg);
3685 }
3686 
3687 static void selinux_msg_msg_free_security(struct msg_msg *msg)
3688 {
3689 	msg_msg_free_security(msg);
3690 }
3691 
3692 /* message queue security operations */
3693 static int selinux_msg_queue_alloc_security(struct msg_queue *msq)
3694 {
3695 	struct task_security_struct *tsec;
3696 	struct ipc_security_struct *isec;
3697 	struct avc_audit_data ad;
3698 	int rc;
3699 
3700 	rc = ipc_alloc_security(current, &msq->q_perm, SECCLASS_MSGQ);
3701 	if (rc)
3702 		return rc;
3703 
3704 	tsec = current->security;
3705 	isec = msq->q_perm.security;
3706 
3707 	AVC_AUDIT_DATA_INIT(&ad, IPC);
3708  	ad.u.ipc_id = msq->q_perm.key;
3709 
3710 	rc = avc_has_perm(tsec->sid, isec->sid, SECCLASS_MSGQ,
3711 			  MSGQ__CREATE, &ad);
3712 	if (rc) {
3713 		ipc_free_security(&msq->q_perm);
3714 		return rc;
3715 	}
3716 	return 0;
3717 }
3718 
3719 static void selinux_msg_queue_free_security(struct msg_queue *msq)
3720 {
3721 	ipc_free_security(&msq->q_perm);
3722 }
3723 
3724 static int selinux_msg_queue_associate(struct msg_queue *msq, int msqflg)
3725 {
3726 	struct task_security_struct *tsec;
3727 	struct ipc_security_struct *isec;
3728 	struct avc_audit_data ad;
3729 
3730 	tsec = current->security;
3731 	isec = msq->q_perm.security;
3732 
3733 	AVC_AUDIT_DATA_INIT(&ad, IPC);
3734 	ad.u.ipc_id = msq->q_perm.key;
3735 
3736 	return avc_has_perm(tsec->sid, isec->sid, SECCLASS_MSGQ,
3737 			    MSGQ__ASSOCIATE, &ad);
3738 }
3739 
3740 static int selinux_msg_queue_msgctl(struct msg_queue *msq, int cmd)
3741 {
3742 	int err;
3743 	int perms;
3744 
3745 	switch(cmd) {
3746 	case IPC_INFO:
3747 	case MSG_INFO:
3748 		/* No specific object, just general system-wide information. */
3749 		return task_has_system(current, SYSTEM__IPC_INFO);
3750 	case IPC_STAT:
3751 	case MSG_STAT:
3752 		perms = MSGQ__GETATTR | MSGQ__ASSOCIATE;
3753 		break;
3754 	case IPC_SET:
3755 		perms = MSGQ__SETATTR;
3756 		break;
3757 	case IPC_RMID:
3758 		perms = MSGQ__DESTROY;
3759 		break;
3760 	default:
3761 		return 0;
3762 	}
3763 
3764 	err = ipc_has_perm(&msq->q_perm, perms);
3765 	return err;
3766 }
3767 
3768 static int selinux_msg_queue_msgsnd(struct msg_queue *msq, struct msg_msg *msg, int msqflg)
3769 {
3770 	struct task_security_struct *tsec;
3771 	struct ipc_security_struct *isec;
3772 	struct msg_security_struct *msec;
3773 	struct avc_audit_data ad;
3774 	int rc;
3775 
3776 	tsec = current->security;
3777 	isec = msq->q_perm.security;
3778 	msec = msg->security;
3779 
3780 	/*
3781 	 * First time through, need to assign label to the message
3782 	 */
3783 	if (msec->sid == SECINITSID_UNLABELED) {
3784 		/*
3785 		 * Compute new sid based on current process and
3786 		 * message queue this message will be stored in
3787 		 */
3788 		rc = security_transition_sid(tsec->sid,
3789 					     isec->sid,
3790 					     SECCLASS_MSG,
3791 					     &msec->sid);
3792 		if (rc)
3793 			return rc;
3794 	}
3795 
3796 	AVC_AUDIT_DATA_INIT(&ad, IPC);
3797 	ad.u.ipc_id = msq->q_perm.key;
3798 
3799 	/* Can this process write to the queue? */
3800 	rc = avc_has_perm(tsec->sid, isec->sid, SECCLASS_MSGQ,
3801 			  MSGQ__WRITE, &ad);
3802 	if (!rc)
3803 		/* Can this process send the message */
3804 		rc = avc_has_perm(tsec->sid, msec->sid,
3805 				  SECCLASS_MSG, MSG__SEND, &ad);
3806 	if (!rc)
3807 		/* Can the message be put in the queue? */
3808 		rc = avc_has_perm(msec->sid, isec->sid,
3809 				  SECCLASS_MSGQ, MSGQ__ENQUEUE, &ad);
3810 
3811 	return rc;
3812 }
3813 
3814 static int selinux_msg_queue_msgrcv(struct msg_queue *msq, struct msg_msg *msg,
3815 				    struct task_struct *target,
3816 				    long type, int mode)
3817 {
3818 	struct task_security_struct *tsec;
3819 	struct ipc_security_struct *isec;
3820 	struct msg_security_struct *msec;
3821 	struct avc_audit_data ad;
3822 	int rc;
3823 
3824 	tsec = target->security;
3825 	isec = msq->q_perm.security;
3826 	msec = msg->security;
3827 
3828 	AVC_AUDIT_DATA_INIT(&ad, IPC);
3829  	ad.u.ipc_id = msq->q_perm.key;
3830 
3831 	rc = avc_has_perm(tsec->sid, isec->sid,
3832 			  SECCLASS_MSGQ, MSGQ__READ, &ad);
3833 	if (!rc)
3834 		rc = avc_has_perm(tsec->sid, msec->sid,
3835 				  SECCLASS_MSG, MSG__RECEIVE, &ad);
3836 	return rc;
3837 }
3838 
3839 /* Shared Memory security operations */
3840 static int selinux_shm_alloc_security(struct shmid_kernel *shp)
3841 {
3842 	struct task_security_struct *tsec;
3843 	struct ipc_security_struct *isec;
3844 	struct avc_audit_data ad;
3845 	int rc;
3846 
3847 	rc = ipc_alloc_security(current, &shp->shm_perm, SECCLASS_SHM);
3848 	if (rc)
3849 		return rc;
3850 
3851 	tsec = current->security;
3852 	isec = shp->shm_perm.security;
3853 
3854 	AVC_AUDIT_DATA_INIT(&ad, IPC);
3855  	ad.u.ipc_id = shp->shm_perm.key;
3856 
3857 	rc = avc_has_perm(tsec->sid, isec->sid, SECCLASS_SHM,
3858 			  SHM__CREATE, &ad);
3859 	if (rc) {
3860 		ipc_free_security(&shp->shm_perm);
3861 		return rc;
3862 	}
3863 	return 0;
3864 }
3865 
3866 static void selinux_shm_free_security(struct shmid_kernel *shp)
3867 {
3868 	ipc_free_security(&shp->shm_perm);
3869 }
3870 
3871 static int selinux_shm_associate(struct shmid_kernel *shp, int shmflg)
3872 {
3873 	struct task_security_struct *tsec;
3874 	struct ipc_security_struct *isec;
3875 	struct avc_audit_data ad;
3876 
3877 	tsec = current->security;
3878 	isec = shp->shm_perm.security;
3879 
3880 	AVC_AUDIT_DATA_INIT(&ad, IPC);
3881 	ad.u.ipc_id = shp->shm_perm.key;
3882 
3883 	return avc_has_perm(tsec->sid, isec->sid, SECCLASS_SHM,
3884 			    SHM__ASSOCIATE, &ad);
3885 }
3886 
3887 /* Note, at this point, shp is locked down */
3888 static int selinux_shm_shmctl(struct shmid_kernel *shp, int cmd)
3889 {
3890 	int perms;
3891 	int err;
3892 
3893 	switch(cmd) {
3894 	case IPC_INFO:
3895 	case SHM_INFO:
3896 		/* No specific object, just general system-wide information. */
3897 		return task_has_system(current, SYSTEM__IPC_INFO);
3898 	case IPC_STAT:
3899 	case SHM_STAT:
3900 		perms = SHM__GETATTR | SHM__ASSOCIATE;
3901 		break;
3902 	case IPC_SET:
3903 		perms = SHM__SETATTR;
3904 		break;
3905 	case SHM_LOCK:
3906 	case SHM_UNLOCK:
3907 		perms = SHM__LOCK;
3908 		break;
3909 	case IPC_RMID:
3910 		perms = SHM__DESTROY;
3911 		break;
3912 	default:
3913 		return 0;
3914 	}
3915 
3916 	err = ipc_has_perm(&shp->shm_perm, perms);
3917 	return err;
3918 }
3919 
3920 static int selinux_shm_shmat(struct shmid_kernel *shp,
3921 			     char __user *shmaddr, int shmflg)
3922 {
3923 	u32 perms;
3924 	int rc;
3925 
3926 	rc = secondary_ops->shm_shmat(shp, shmaddr, shmflg);
3927 	if (rc)
3928 		return rc;
3929 
3930 	if (shmflg & SHM_RDONLY)
3931 		perms = SHM__READ;
3932 	else
3933 		perms = SHM__READ | SHM__WRITE;
3934 
3935 	return ipc_has_perm(&shp->shm_perm, perms);
3936 }
3937 
3938 /* Semaphore security operations */
3939 static int selinux_sem_alloc_security(struct sem_array *sma)
3940 {
3941 	struct task_security_struct *tsec;
3942 	struct ipc_security_struct *isec;
3943 	struct avc_audit_data ad;
3944 	int rc;
3945 
3946 	rc = ipc_alloc_security(current, &sma->sem_perm, SECCLASS_SEM);
3947 	if (rc)
3948 		return rc;
3949 
3950 	tsec = current->security;
3951 	isec = sma->sem_perm.security;
3952 
3953 	AVC_AUDIT_DATA_INIT(&ad, IPC);
3954  	ad.u.ipc_id = sma->sem_perm.key;
3955 
3956 	rc = avc_has_perm(tsec->sid, isec->sid, SECCLASS_SEM,
3957 			  SEM__CREATE, &ad);
3958 	if (rc) {
3959 		ipc_free_security(&sma->sem_perm);
3960 		return rc;
3961 	}
3962 	return 0;
3963 }
3964 
3965 static void selinux_sem_free_security(struct sem_array *sma)
3966 {
3967 	ipc_free_security(&sma->sem_perm);
3968 }
3969 
3970 static int selinux_sem_associate(struct sem_array *sma, int semflg)
3971 {
3972 	struct task_security_struct *tsec;
3973 	struct ipc_security_struct *isec;
3974 	struct avc_audit_data ad;
3975 
3976 	tsec = current->security;
3977 	isec = sma->sem_perm.security;
3978 
3979 	AVC_AUDIT_DATA_INIT(&ad, IPC);
3980 	ad.u.ipc_id = sma->sem_perm.key;
3981 
3982 	return avc_has_perm(tsec->sid, isec->sid, SECCLASS_SEM,
3983 			    SEM__ASSOCIATE, &ad);
3984 }
3985 
3986 /* Note, at this point, sma is locked down */
3987 static int selinux_sem_semctl(struct sem_array *sma, int cmd)
3988 {
3989 	int err;
3990 	u32 perms;
3991 
3992 	switch(cmd) {
3993 	case IPC_INFO:
3994 	case SEM_INFO:
3995 		/* No specific object, just general system-wide information. */
3996 		return task_has_system(current, SYSTEM__IPC_INFO);
3997 	case GETPID:
3998 	case GETNCNT:
3999 	case GETZCNT:
4000 		perms = SEM__GETATTR;
4001 		break;
4002 	case GETVAL:
4003 	case GETALL:
4004 		perms = SEM__READ;
4005 		break;
4006 	case SETVAL:
4007 	case SETALL:
4008 		perms = SEM__WRITE;
4009 		break;
4010 	case IPC_RMID:
4011 		perms = SEM__DESTROY;
4012 		break;
4013 	case IPC_SET:
4014 		perms = SEM__SETATTR;
4015 		break;
4016 	case IPC_STAT:
4017 	case SEM_STAT:
4018 		perms = SEM__GETATTR | SEM__ASSOCIATE;
4019 		break;
4020 	default:
4021 		return 0;
4022 	}
4023 
4024 	err = ipc_has_perm(&sma->sem_perm, perms);
4025 	return err;
4026 }
4027 
4028 static int selinux_sem_semop(struct sem_array *sma,
4029 			     struct sembuf *sops, unsigned nsops, int alter)
4030 {
4031 	u32 perms;
4032 
4033 	if (alter)
4034 		perms = SEM__READ | SEM__WRITE;
4035 	else
4036 		perms = SEM__READ;
4037 
4038 	return ipc_has_perm(&sma->sem_perm, perms);
4039 }
4040 
4041 static int selinux_ipc_permission(struct kern_ipc_perm *ipcp, short flag)
4042 {
4043 	u32 av = 0;
4044 
4045 	av = 0;
4046 	if (flag & S_IRUGO)
4047 		av |= IPC__UNIX_READ;
4048 	if (flag & S_IWUGO)
4049 		av |= IPC__UNIX_WRITE;
4050 
4051 	if (av == 0)
4052 		return 0;
4053 
4054 	return ipc_has_perm(ipcp, av);
4055 }
4056 
4057 /* module stacking operations */
4058 static int selinux_register_security (const char *name, struct security_operations *ops)
4059 {
4060 	if (secondary_ops != original_ops) {
4061 		printk(KERN_INFO "%s:  There is already a secondary security "
4062 		       "module registered.\n", __FUNCTION__);
4063 		return -EINVAL;
4064  	}
4065 
4066 	secondary_ops = ops;
4067 
4068 	printk(KERN_INFO "%s:  Registering secondary module %s\n",
4069 	       __FUNCTION__,
4070 	       name);
4071 
4072 	return 0;
4073 }
4074 
4075 static int selinux_unregister_security (const char *name, struct security_operations *ops)
4076 {
4077 	if (ops != secondary_ops) {
4078 		printk (KERN_INFO "%s:  trying to unregister a security module "
4079 		        "that is not registered.\n", __FUNCTION__);
4080 		return -EINVAL;
4081 	}
4082 
4083 	secondary_ops = original_ops;
4084 
4085 	return 0;
4086 }
4087 
4088 static void selinux_d_instantiate (struct dentry *dentry, struct inode *inode)
4089 {
4090 	if (inode)
4091 		inode_doinit_with_dentry(inode, dentry);
4092 }
4093 
4094 static int selinux_getprocattr(struct task_struct *p,
4095 			       char *name, void *value, size_t size)
4096 {
4097 	struct task_security_struct *tsec;
4098 	u32 sid, len;
4099 	char *context;
4100 	int error;
4101 
4102 	if (current != p) {
4103 		error = task_has_perm(current, p, PROCESS__GETATTR);
4104 		if (error)
4105 			return error;
4106 	}
4107 
4108 	if (!size)
4109 		return -ERANGE;
4110 
4111 	tsec = p->security;
4112 
4113 	if (!strcmp(name, "current"))
4114 		sid = tsec->sid;
4115 	else if (!strcmp(name, "prev"))
4116 		sid = tsec->osid;
4117 	else if (!strcmp(name, "exec"))
4118 		sid = tsec->exec_sid;
4119 	else if (!strcmp(name, "fscreate"))
4120 		sid = tsec->create_sid;
4121 	else
4122 		return -EINVAL;
4123 
4124 	if (!sid)
4125 		return 0;
4126 
4127 	error = security_sid_to_context(sid, &context, &len);
4128 	if (error)
4129 		return error;
4130 	if (len > size) {
4131 		kfree(context);
4132 		return -ERANGE;
4133 	}
4134 	memcpy(value, context, len);
4135 	kfree(context);
4136 	return len;
4137 }
4138 
4139 static int selinux_setprocattr(struct task_struct *p,
4140 			       char *name, void *value, size_t size)
4141 {
4142 	struct task_security_struct *tsec;
4143 	u32 sid = 0;
4144 	int error;
4145 	char *str = value;
4146 
4147 	if (current != p) {
4148 		/* SELinux only allows a process to change its own
4149 		   security attributes. */
4150 		return -EACCES;
4151 	}
4152 
4153 	/*
4154 	 * Basic control over ability to set these attributes at all.
4155 	 * current == p, but we'll pass them separately in case the
4156 	 * above restriction is ever removed.
4157 	 */
4158 	if (!strcmp(name, "exec"))
4159 		error = task_has_perm(current, p, PROCESS__SETEXEC);
4160 	else if (!strcmp(name, "fscreate"))
4161 		error = task_has_perm(current, p, PROCESS__SETFSCREATE);
4162 	else if (!strcmp(name, "current"))
4163 		error = task_has_perm(current, p, PROCESS__SETCURRENT);
4164 	else
4165 		error = -EINVAL;
4166 	if (error)
4167 		return error;
4168 
4169 	/* Obtain a SID for the context, if one was specified. */
4170 	if (size && str[1] && str[1] != '\n') {
4171 		if (str[size-1] == '\n') {
4172 			str[size-1] = 0;
4173 			size--;
4174 		}
4175 		error = security_context_to_sid(value, size, &sid);
4176 		if (error)
4177 			return error;
4178 	}
4179 
4180 	/* Permission checking based on the specified context is
4181 	   performed during the actual operation (execve,
4182 	   open/mkdir/...), when we know the full context of the
4183 	   operation.  See selinux_bprm_set_security for the execve
4184 	   checks and may_create for the file creation checks. The
4185 	   operation will then fail if the context is not permitted. */
4186 	tsec = p->security;
4187 	if (!strcmp(name, "exec"))
4188 		tsec->exec_sid = sid;
4189 	else if (!strcmp(name, "fscreate"))
4190 		tsec->create_sid = sid;
4191 	else if (!strcmp(name, "current")) {
4192 		struct av_decision avd;
4193 
4194 		if (sid == 0)
4195 			return -EINVAL;
4196 
4197 		/* Only allow single threaded processes to change context */
4198 		if (atomic_read(&p->mm->mm_users) != 1) {
4199 			struct task_struct *g, *t;
4200 			struct mm_struct *mm = p->mm;
4201 			read_lock(&tasklist_lock);
4202 			do_each_thread(g, t)
4203 				if (t->mm == mm && t != p) {
4204 					read_unlock(&tasklist_lock);
4205 					return -EPERM;
4206 				}
4207 			while_each_thread(g, t);
4208 			read_unlock(&tasklist_lock);
4209                 }
4210 
4211 		/* Check permissions for the transition. */
4212 		error = avc_has_perm(tsec->sid, sid, SECCLASS_PROCESS,
4213 		                     PROCESS__DYNTRANSITION, NULL);
4214 		if (error)
4215 			return error;
4216 
4217 		/* Check for ptracing, and update the task SID if ok.
4218 		   Otherwise, leave SID unchanged and fail. */
4219 		task_lock(p);
4220 		if (p->ptrace & PT_PTRACED) {
4221 			error = avc_has_perm_noaudit(tsec->ptrace_sid, sid,
4222 						     SECCLASS_PROCESS,
4223 						     PROCESS__PTRACE, &avd);
4224 			if (!error)
4225 				tsec->sid = sid;
4226 			task_unlock(p);
4227 			avc_audit(tsec->ptrace_sid, sid, SECCLASS_PROCESS,
4228 				  PROCESS__PTRACE, &avd, error, NULL);
4229 			if (error)
4230 				return error;
4231 		} else {
4232 			tsec->sid = sid;
4233 			task_unlock(p);
4234 		}
4235 	}
4236 	else
4237 		return -EINVAL;
4238 
4239 	return size;
4240 }
4241 
4242 static struct security_operations selinux_ops = {
4243 	.ptrace =			selinux_ptrace,
4244 	.capget =			selinux_capget,
4245 	.capset_check =			selinux_capset_check,
4246 	.capset_set =			selinux_capset_set,
4247 	.sysctl =			selinux_sysctl,
4248 	.capable =			selinux_capable,
4249 	.quotactl =			selinux_quotactl,
4250 	.quota_on =			selinux_quota_on,
4251 	.syslog =			selinux_syslog,
4252 	.vm_enough_memory =		selinux_vm_enough_memory,
4253 
4254 	.netlink_send =			selinux_netlink_send,
4255         .netlink_recv =			selinux_netlink_recv,
4256 
4257 	.bprm_alloc_security =		selinux_bprm_alloc_security,
4258 	.bprm_free_security =		selinux_bprm_free_security,
4259 	.bprm_apply_creds =		selinux_bprm_apply_creds,
4260 	.bprm_post_apply_creds =	selinux_bprm_post_apply_creds,
4261 	.bprm_set_security =		selinux_bprm_set_security,
4262 	.bprm_check_security =		selinux_bprm_check_security,
4263 	.bprm_secureexec =		selinux_bprm_secureexec,
4264 
4265 	.sb_alloc_security =		selinux_sb_alloc_security,
4266 	.sb_free_security =		selinux_sb_free_security,
4267 	.sb_copy_data =			selinux_sb_copy_data,
4268 	.sb_kern_mount =	        selinux_sb_kern_mount,
4269 	.sb_statfs =			selinux_sb_statfs,
4270 	.sb_mount =			selinux_mount,
4271 	.sb_umount =			selinux_umount,
4272 
4273 	.inode_alloc_security =		selinux_inode_alloc_security,
4274 	.inode_free_security =		selinux_inode_free_security,
4275 	.inode_init_security =		selinux_inode_init_security,
4276 	.inode_create =			selinux_inode_create,
4277 	.inode_link =			selinux_inode_link,
4278 	.inode_unlink =			selinux_inode_unlink,
4279 	.inode_symlink =		selinux_inode_symlink,
4280 	.inode_mkdir =			selinux_inode_mkdir,
4281 	.inode_rmdir =			selinux_inode_rmdir,
4282 	.inode_mknod =			selinux_inode_mknod,
4283 	.inode_rename =			selinux_inode_rename,
4284 	.inode_readlink =		selinux_inode_readlink,
4285 	.inode_follow_link =		selinux_inode_follow_link,
4286 	.inode_permission =		selinux_inode_permission,
4287 	.inode_setattr =		selinux_inode_setattr,
4288 	.inode_getattr =		selinux_inode_getattr,
4289 	.inode_setxattr =		selinux_inode_setxattr,
4290 	.inode_post_setxattr =		selinux_inode_post_setxattr,
4291 	.inode_getxattr =		selinux_inode_getxattr,
4292 	.inode_listxattr =		selinux_inode_listxattr,
4293 	.inode_removexattr =		selinux_inode_removexattr,
4294 	.inode_getsecurity =            selinux_inode_getsecurity,
4295 	.inode_setsecurity =            selinux_inode_setsecurity,
4296 	.inode_listsecurity =           selinux_inode_listsecurity,
4297 
4298 	.file_permission =		selinux_file_permission,
4299 	.file_alloc_security =		selinux_file_alloc_security,
4300 	.file_free_security =		selinux_file_free_security,
4301 	.file_ioctl =			selinux_file_ioctl,
4302 	.file_mmap =			selinux_file_mmap,
4303 	.file_mprotect =		selinux_file_mprotect,
4304 	.file_lock =			selinux_file_lock,
4305 	.file_fcntl =			selinux_file_fcntl,
4306 	.file_set_fowner =		selinux_file_set_fowner,
4307 	.file_send_sigiotask =		selinux_file_send_sigiotask,
4308 	.file_receive =			selinux_file_receive,
4309 
4310 	.task_create =			selinux_task_create,
4311 	.task_alloc_security =		selinux_task_alloc_security,
4312 	.task_free_security =		selinux_task_free_security,
4313 	.task_setuid =			selinux_task_setuid,
4314 	.task_post_setuid =		selinux_task_post_setuid,
4315 	.task_setgid =			selinux_task_setgid,
4316 	.task_setpgid =			selinux_task_setpgid,
4317 	.task_getpgid =			selinux_task_getpgid,
4318 	.task_getsid =		        selinux_task_getsid,
4319 	.task_setgroups =		selinux_task_setgroups,
4320 	.task_setnice =			selinux_task_setnice,
4321 	.task_setrlimit =		selinux_task_setrlimit,
4322 	.task_setscheduler =		selinux_task_setscheduler,
4323 	.task_getscheduler =		selinux_task_getscheduler,
4324 	.task_kill =			selinux_task_kill,
4325 	.task_wait =			selinux_task_wait,
4326 	.task_prctl =			selinux_task_prctl,
4327 	.task_reparent_to_init =	selinux_task_reparent_to_init,
4328 	.task_to_inode =                selinux_task_to_inode,
4329 
4330 	.ipc_permission =		selinux_ipc_permission,
4331 
4332 	.msg_msg_alloc_security =	selinux_msg_msg_alloc_security,
4333 	.msg_msg_free_security =	selinux_msg_msg_free_security,
4334 
4335 	.msg_queue_alloc_security =	selinux_msg_queue_alloc_security,
4336 	.msg_queue_free_security =	selinux_msg_queue_free_security,
4337 	.msg_queue_associate =		selinux_msg_queue_associate,
4338 	.msg_queue_msgctl =		selinux_msg_queue_msgctl,
4339 	.msg_queue_msgsnd =		selinux_msg_queue_msgsnd,
4340 	.msg_queue_msgrcv =		selinux_msg_queue_msgrcv,
4341 
4342 	.shm_alloc_security =		selinux_shm_alloc_security,
4343 	.shm_free_security =		selinux_shm_free_security,
4344 	.shm_associate =		selinux_shm_associate,
4345 	.shm_shmctl =			selinux_shm_shmctl,
4346 	.shm_shmat =			selinux_shm_shmat,
4347 
4348 	.sem_alloc_security = 		selinux_sem_alloc_security,
4349 	.sem_free_security =  		selinux_sem_free_security,
4350 	.sem_associate =		selinux_sem_associate,
4351 	.sem_semctl =			selinux_sem_semctl,
4352 	.sem_semop =			selinux_sem_semop,
4353 
4354 	.register_security =		selinux_register_security,
4355 	.unregister_security =		selinux_unregister_security,
4356 
4357 	.d_instantiate =                selinux_d_instantiate,
4358 
4359 	.getprocattr =                  selinux_getprocattr,
4360 	.setprocattr =                  selinux_setprocattr,
4361 
4362 #ifdef CONFIG_SECURITY_NETWORK
4363         .unix_stream_connect =		selinux_socket_unix_stream_connect,
4364 	.unix_may_send =		selinux_socket_unix_may_send,
4365 
4366 	.socket_create =		selinux_socket_create,
4367 	.socket_post_create =		selinux_socket_post_create,
4368 	.socket_bind =			selinux_socket_bind,
4369 	.socket_connect =		selinux_socket_connect,
4370 	.socket_listen =		selinux_socket_listen,
4371 	.socket_accept =		selinux_socket_accept,
4372 	.socket_sendmsg =		selinux_socket_sendmsg,
4373 	.socket_recvmsg =		selinux_socket_recvmsg,
4374 	.socket_getsockname =		selinux_socket_getsockname,
4375 	.socket_getpeername =		selinux_socket_getpeername,
4376 	.socket_getsockopt =		selinux_socket_getsockopt,
4377 	.socket_setsockopt =		selinux_socket_setsockopt,
4378 	.socket_shutdown =		selinux_socket_shutdown,
4379 	.socket_sock_rcv_skb =		selinux_socket_sock_rcv_skb,
4380 	.socket_getpeersec =		selinux_socket_getpeersec,
4381 	.sk_alloc_security =		selinux_sk_alloc_security,
4382 	.sk_free_security =		selinux_sk_free_security,
4383 #endif
4384 };
4385 
4386 static __init int selinux_init(void)
4387 {
4388 	struct task_security_struct *tsec;
4389 
4390 	if (!selinux_enabled) {
4391 		printk(KERN_INFO "SELinux:  Disabled at boot.\n");
4392 		return 0;
4393 	}
4394 
4395 	printk(KERN_INFO "SELinux:  Initializing.\n");
4396 
4397 	/* Set the security state for the initial task. */
4398 	if (task_alloc_security(current))
4399 		panic("SELinux:  Failed to initialize initial task.\n");
4400 	tsec = current->security;
4401 	tsec->osid = tsec->sid = SECINITSID_KERNEL;
4402 
4403 	avc_init();
4404 
4405 	original_ops = secondary_ops = security_ops;
4406 	if (!secondary_ops)
4407 		panic ("SELinux: No initial security operations\n");
4408 	if (register_security (&selinux_ops))
4409 		panic("SELinux: Unable to register with kernel.\n");
4410 
4411 	if (selinux_enforcing) {
4412 		printk(KERN_INFO "SELinux:  Starting in enforcing mode\n");
4413 	} else {
4414 		printk(KERN_INFO "SELinux:  Starting in permissive mode\n");
4415 	}
4416 	return 0;
4417 }
4418 
4419 void selinux_complete_init(void)
4420 {
4421 	printk(KERN_INFO "SELinux:  Completing initialization.\n");
4422 
4423 	/* Set up any superblocks initialized prior to the policy load. */
4424 	printk(KERN_INFO "SELinux:  Setting up existing superblocks.\n");
4425 	spin_lock(&sb_security_lock);
4426 next_sb:
4427 	if (!list_empty(&superblock_security_head)) {
4428 		struct superblock_security_struct *sbsec =
4429 				list_entry(superblock_security_head.next,
4430 				           struct superblock_security_struct,
4431 				           list);
4432 		struct super_block *sb = sbsec->sb;
4433 		spin_lock(&sb_lock);
4434 		sb->s_count++;
4435 		spin_unlock(&sb_lock);
4436 		spin_unlock(&sb_security_lock);
4437 		down_read(&sb->s_umount);
4438 		if (sb->s_root)
4439 			superblock_doinit(sb, NULL);
4440 		drop_super(sb);
4441 		spin_lock(&sb_security_lock);
4442 		list_del_init(&sbsec->list);
4443 		goto next_sb;
4444 	}
4445 	spin_unlock(&sb_security_lock);
4446 }
4447 
4448 /* SELinux requires early initialization in order to label
4449    all processes and objects when they are created. */
4450 security_initcall(selinux_init);
4451 
4452 #if defined(CONFIG_SECURITY_NETWORK) && defined(CONFIG_NETFILTER)
4453 
4454 static struct nf_hook_ops selinux_ipv4_op = {
4455 	.hook =		selinux_ipv4_postroute_last,
4456 	.owner =	THIS_MODULE,
4457 	.pf =		PF_INET,
4458 	.hooknum =	NF_IP_POST_ROUTING,
4459 	.priority =	NF_IP_PRI_SELINUX_LAST,
4460 };
4461 
4462 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
4463 
4464 static struct nf_hook_ops selinux_ipv6_op = {
4465 	.hook =		selinux_ipv6_postroute_last,
4466 	.owner =	THIS_MODULE,
4467 	.pf =		PF_INET6,
4468 	.hooknum =	NF_IP6_POST_ROUTING,
4469 	.priority =	NF_IP6_PRI_SELINUX_LAST,
4470 };
4471 
4472 #endif	/* IPV6 */
4473 
4474 static int __init selinux_nf_ip_init(void)
4475 {
4476 	int err = 0;
4477 
4478 	if (!selinux_enabled)
4479 		goto out;
4480 
4481 	printk(KERN_INFO "SELinux:  Registering netfilter hooks\n");
4482 
4483 	err = nf_register_hook(&selinux_ipv4_op);
4484 	if (err)
4485 		panic("SELinux: nf_register_hook for IPv4: error %d\n", err);
4486 
4487 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
4488 
4489 	err = nf_register_hook(&selinux_ipv6_op);
4490 	if (err)
4491 		panic("SELinux: nf_register_hook for IPv6: error %d\n", err);
4492 
4493 #endif	/* IPV6 */
4494 out:
4495 	return err;
4496 }
4497 
4498 __initcall(selinux_nf_ip_init);
4499 
4500 #ifdef CONFIG_SECURITY_SELINUX_DISABLE
4501 static void selinux_nf_ip_exit(void)
4502 {
4503 	printk(KERN_INFO "SELinux:  Unregistering netfilter hooks\n");
4504 
4505 	nf_unregister_hook(&selinux_ipv4_op);
4506 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
4507 	nf_unregister_hook(&selinux_ipv6_op);
4508 #endif	/* IPV6 */
4509 }
4510 #endif
4511 
4512 #else /* CONFIG_SECURITY_NETWORK && CONFIG_NETFILTER */
4513 
4514 #ifdef CONFIG_SECURITY_SELINUX_DISABLE
4515 #define selinux_nf_ip_exit()
4516 #endif
4517 
4518 #endif /* CONFIG_SECURITY_NETWORK && CONFIG_NETFILTER */
4519 
4520 #ifdef CONFIG_SECURITY_SELINUX_DISABLE
4521 int selinux_disable(void)
4522 {
4523 	extern void exit_sel_fs(void);
4524 	static int selinux_disabled = 0;
4525 
4526 	if (ss_initialized) {
4527 		/* Not permitted after initial policy load. */
4528 		return -EINVAL;
4529 	}
4530 
4531 	if (selinux_disabled) {
4532 		/* Only do this once. */
4533 		return -EINVAL;
4534 	}
4535 
4536 	printk(KERN_INFO "SELinux:  Disabled at runtime.\n");
4537 
4538 	selinux_disabled = 1;
4539 
4540 	/* Reset security_ops to the secondary module, dummy or capability. */
4541 	security_ops = secondary_ops;
4542 
4543 	/* Unregister netfilter hooks. */
4544 	selinux_nf_ip_exit();
4545 
4546 	/* Unregister selinuxfs. */
4547 	exit_sel_fs();
4548 
4549 	return 0;
4550 }
4551 #endif
4552 
4553 
4554