xref: /linux/security/selinux/hooks.c (revision 858259cf7d1c443c836a2022b78cb281f0a9b95e)
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 (name) {
1990 		namep = kstrdup(XATTR_SELINUX_SUFFIX, GFP_KERNEL);
1991 		if (!namep)
1992 			return -ENOMEM;
1993 		*name = namep;
1994 	}
1995 
1996 	if (value && len) {
1997 		rc = security_sid_to_context(newsid, &context, &clen);
1998 		if (rc) {
1999 			kfree(namep);
2000 			return rc;
2001 		}
2002 		*value = context;
2003 		*len = clen;
2004 	}
2005 
2006 	return 0;
2007 }
2008 
2009 static int selinux_inode_create(struct inode *dir, struct dentry *dentry, int mask)
2010 {
2011 	return may_create(dir, dentry, SECCLASS_FILE);
2012 }
2013 
2014 static int selinux_inode_link(struct dentry *old_dentry, struct inode *dir, struct dentry *new_dentry)
2015 {
2016 	int rc;
2017 
2018 	rc = secondary_ops->inode_link(old_dentry,dir,new_dentry);
2019 	if (rc)
2020 		return rc;
2021 	return may_link(dir, old_dentry, MAY_LINK);
2022 }
2023 
2024 static int selinux_inode_unlink(struct inode *dir, struct dentry *dentry)
2025 {
2026 	int rc;
2027 
2028 	rc = secondary_ops->inode_unlink(dir, dentry);
2029 	if (rc)
2030 		return rc;
2031 	return may_link(dir, dentry, MAY_UNLINK);
2032 }
2033 
2034 static int selinux_inode_symlink(struct inode *dir, struct dentry *dentry, const char *name)
2035 {
2036 	return may_create(dir, dentry, SECCLASS_LNK_FILE);
2037 }
2038 
2039 static int selinux_inode_mkdir(struct inode *dir, struct dentry *dentry, int mask)
2040 {
2041 	return may_create(dir, dentry, SECCLASS_DIR);
2042 }
2043 
2044 static int selinux_inode_rmdir(struct inode *dir, struct dentry *dentry)
2045 {
2046 	return may_link(dir, dentry, MAY_RMDIR);
2047 }
2048 
2049 static int selinux_inode_mknod(struct inode *dir, struct dentry *dentry, int mode, dev_t dev)
2050 {
2051 	int rc;
2052 
2053 	rc = secondary_ops->inode_mknod(dir, dentry, mode, dev);
2054 	if (rc)
2055 		return rc;
2056 
2057 	return may_create(dir, dentry, inode_mode_to_security_class(mode));
2058 }
2059 
2060 static int selinux_inode_rename(struct inode *old_inode, struct dentry *old_dentry,
2061                                 struct inode *new_inode, struct dentry *new_dentry)
2062 {
2063 	return may_rename(old_inode, old_dentry, new_inode, new_dentry);
2064 }
2065 
2066 static int selinux_inode_readlink(struct dentry *dentry)
2067 {
2068 	return dentry_has_perm(current, NULL, dentry, FILE__READ);
2069 }
2070 
2071 static int selinux_inode_follow_link(struct dentry *dentry, struct nameidata *nameidata)
2072 {
2073 	int rc;
2074 
2075 	rc = secondary_ops->inode_follow_link(dentry,nameidata);
2076 	if (rc)
2077 		return rc;
2078 	return dentry_has_perm(current, NULL, dentry, FILE__READ);
2079 }
2080 
2081 static int selinux_inode_permission(struct inode *inode, int mask,
2082 				    struct nameidata *nd)
2083 {
2084 	int rc;
2085 
2086 	rc = secondary_ops->inode_permission(inode, mask, nd);
2087 	if (rc)
2088 		return rc;
2089 
2090 	if (!mask) {
2091 		/* No permission to check.  Existence test. */
2092 		return 0;
2093 	}
2094 
2095 	return inode_has_perm(current, inode,
2096 			       file_mask_to_av(inode->i_mode, mask), NULL);
2097 }
2098 
2099 static int selinux_inode_setattr(struct dentry *dentry, struct iattr *iattr)
2100 {
2101 	int rc;
2102 
2103 	rc = secondary_ops->inode_setattr(dentry, iattr);
2104 	if (rc)
2105 		return rc;
2106 
2107 	if (iattr->ia_valid & ATTR_FORCE)
2108 		return 0;
2109 
2110 	if (iattr->ia_valid & (ATTR_MODE | ATTR_UID | ATTR_GID |
2111 			       ATTR_ATIME_SET | ATTR_MTIME_SET))
2112 		return dentry_has_perm(current, NULL, dentry, FILE__SETATTR);
2113 
2114 	return dentry_has_perm(current, NULL, dentry, FILE__WRITE);
2115 }
2116 
2117 static int selinux_inode_getattr(struct vfsmount *mnt, struct dentry *dentry)
2118 {
2119 	return dentry_has_perm(current, mnt, dentry, FILE__GETATTR);
2120 }
2121 
2122 static int selinux_inode_setxattr(struct dentry *dentry, char *name, void *value, size_t size, int flags)
2123 {
2124 	struct task_security_struct *tsec = current->security;
2125 	struct inode *inode = dentry->d_inode;
2126 	struct inode_security_struct *isec = inode->i_security;
2127 	struct superblock_security_struct *sbsec;
2128 	struct avc_audit_data ad;
2129 	u32 newsid;
2130 	int rc = 0;
2131 
2132 	if (strcmp(name, XATTR_NAME_SELINUX)) {
2133 		if (!strncmp(name, XATTR_SECURITY_PREFIX,
2134 			     sizeof XATTR_SECURITY_PREFIX - 1) &&
2135 		    !capable(CAP_SYS_ADMIN)) {
2136 			/* A different attribute in the security namespace.
2137 			   Restrict to administrator. */
2138 			return -EPERM;
2139 		}
2140 
2141 		/* Not an attribute we recognize, so just check the
2142 		   ordinary setattr permission. */
2143 		return dentry_has_perm(current, NULL, dentry, FILE__SETATTR);
2144 	}
2145 
2146 	sbsec = inode->i_sb->s_security;
2147 	if (sbsec->behavior == SECURITY_FS_USE_MNTPOINT)
2148 		return -EOPNOTSUPP;
2149 
2150 	if ((current->fsuid != inode->i_uid) && !capable(CAP_FOWNER))
2151 		return -EPERM;
2152 
2153 	AVC_AUDIT_DATA_INIT(&ad,FS);
2154 	ad.u.fs.dentry = dentry;
2155 
2156 	rc = avc_has_perm(tsec->sid, isec->sid, isec->sclass,
2157 			  FILE__RELABELFROM, &ad);
2158 	if (rc)
2159 		return rc;
2160 
2161 	rc = security_context_to_sid(value, size, &newsid);
2162 	if (rc)
2163 		return rc;
2164 
2165 	rc = avc_has_perm(tsec->sid, newsid, isec->sclass,
2166 			  FILE__RELABELTO, &ad);
2167 	if (rc)
2168 		return rc;
2169 
2170 	rc = security_validate_transition(isec->sid, newsid, tsec->sid,
2171 	                                  isec->sclass);
2172 	if (rc)
2173 		return rc;
2174 
2175 	return avc_has_perm(newsid,
2176 			    sbsec->sid,
2177 			    SECCLASS_FILESYSTEM,
2178 			    FILESYSTEM__ASSOCIATE,
2179 			    &ad);
2180 }
2181 
2182 static void selinux_inode_post_setxattr(struct dentry *dentry, char *name,
2183                                         void *value, size_t size, int flags)
2184 {
2185 	struct inode *inode = dentry->d_inode;
2186 	struct inode_security_struct *isec = inode->i_security;
2187 	u32 newsid;
2188 	int rc;
2189 
2190 	if (strcmp(name, XATTR_NAME_SELINUX)) {
2191 		/* Not an attribute we recognize, so nothing to do. */
2192 		return;
2193 	}
2194 
2195 	rc = security_context_to_sid(value, size, &newsid);
2196 	if (rc) {
2197 		printk(KERN_WARNING "%s:  unable to obtain SID for context "
2198 		       "%s, rc=%d\n", __FUNCTION__, (char*)value, -rc);
2199 		return;
2200 	}
2201 
2202 	isec->sid = newsid;
2203 	return;
2204 }
2205 
2206 static int selinux_inode_getxattr (struct dentry *dentry, char *name)
2207 {
2208 	return dentry_has_perm(current, NULL, dentry, FILE__GETATTR);
2209 }
2210 
2211 static int selinux_inode_listxattr (struct dentry *dentry)
2212 {
2213 	return dentry_has_perm(current, NULL, dentry, FILE__GETATTR);
2214 }
2215 
2216 static int selinux_inode_removexattr (struct dentry *dentry, char *name)
2217 {
2218 	if (strcmp(name, XATTR_NAME_SELINUX)) {
2219 		if (!strncmp(name, XATTR_SECURITY_PREFIX,
2220 			     sizeof XATTR_SECURITY_PREFIX - 1) &&
2221 		    !capable(CAP_SYS_ADMIN)) {
2222 			/* A different attribute in the security namespace.
2223 			   Restrict to administrator. */
2224 			return -EPERM;
2225 		}
2226 
2227 		/* Not an attribute we recognize, so just check the
2228 		   ordinary setattr permission. Might want a separate
2229 		   permission for removexattr. */
2230 		return dentry_has_perm(current, NULL, dentry, FILE__SETATTR);
2231 	}
2232 
2233 	/* No one is allowed to remove a SELinux security label.
2234 	   You can change the label, but all data must be labeled. */
2235 	return -EACCES;
2236 }
2237 
2238 /*
2239  * Copy the in-core inode security context value to the user.  If the
2240  * getxattr() prior to this succeeded, check to see if we need to
2241  * canonicalize the value to be finally returned to the user.
2242  *
2243  * Permission check is handled by selinux_inode_getxattr hook.
2244  */
2245 static int selinux_inode_getsecurity(struct inode *inode, const char *name, void *buffer, size_t size, int err)
2246 {
2247 	struct inode_security_struct *isec = inode->i_security;
2248 	char *context;
2249 	unsigned len;
2250 	int rc;
2251 
2252 	if (strcmp(name, XATTR_SELINUX_SUFFIX)) {
2253 		rc = -EOPNOTSUPP;
2254 		goto out;
2255 	}
2256 
2257 	rc = security_sid_to_context(isec->sid, &context, &len);
2258 	if (rc)
2259 		goto out;
2260 
2261 	/* Probe for required buffer size */
2262 	if (!buffer || !size) {
2263 		rc = len;
2264 		goto out_free;
2265 	}
2266 
2267 	if (size < len) {
2268 		rc = -ERANGE;
2269 		goto out_free;
2270 	}
2271 
2272 	if (err > 0) {
2273 		if ((len == err) && !(memcmp(context, buffer, len))) {
2274 			/* Don't need to canonicalize value */
2275 			rc = err;
2276 			goto out_free;
2277 		}
2278 		memset(buffer, 0, size);
2279 	}
2280 	memcpy(buffer, context, len);
2281 	rc = len;
2282 out_free:
2283 	kfree(context);
2284 out:
2285 	return rc;
2286 }
2287 
2288 static int selinux_inode_setsecurity(struct inode *inode, const char *name,
2289                                      const void *value, size_t size, int flags)
2290 {
2291 	struct inode_security_struct *isec = inode->i_security;
2292 	u32 newsid;
2293 	int rc;
2294 
2295 	if (strcmp(name, XATTR_SELINUX_SUFFIX))
2296 		return -EOPNOTSUPP;
2297 
2298 	if (!value || !size)
2299 		return -EACCES;
2300 
2301 	rc = security_context_to_sid((void*)value, size, &newsid);
2302 	if (rc)
2303 		return rc;
2304 
2305 	isec->sid = newsid;
2306 	return 0;
2307 }
2308 
2309 static int selinux_inode_listsecurity(struct inode *inode, char *buffer, size_t buffer_size)
2310 {
2311 	const int len = sizeof(XATTR_NAME_SELINUX);
2312 	if (buffer && len <= buffer_size)
2313 		memcpy(buffer, XATTR_NAME_SELINUX, len);
2314 	return len;
2315 }
2316 
2317 /* file security operations */
2318 
2319 static int selinux_file_permission(struct file *file, int mask)
2320 {
2321 	struct inode *inode = file->f_dentry->d_inode;
2322 
2323 	if (!mask) {
2324 		/* No permission to check.  Existence test. */
2325 		return 0;
2326 	}
2327 
2328 	/* file_mask_to_av won't add FILE__WRITE if MAY_APPEND is set */
2329 	if ((file->f_flags & O_APPEND) && (mask & MAY_WRITE))
2330 		mask |= MAY_APPEND;
2331 
2332 	return file_has_perm(current, file,
2333 			     file_mask_to_av(inode->i_mode, mask));
2334 }
2335 
2336 static int selinux_file_alloc_security(struct file *file)
2337 {
2338 	return file_alloc_security(file);
2339 }
2340 
2341 static void selinux_file_free_security(struct file *file)
2342 {
2343 	file_free_security(file);
2344 }
2345 
2346 static int selinux_file_ioctl(struct file *file, unsigned int cmd,
2347 			      unsigned long arg)
2348 {
2349 	int error = 0;
2350 
2351 	switch (cmd) {
2352 		case FIONREAD:
2353 		/* fall through */
2354 		case FIBMAP:
2355 		/* fall through */
2356 		case FIGETBSZ:
2357 		/* fall through */
2358 		case EXT2_IOC_GETFLAGS:
2359 		/* fall through */
2360 		case EXT2_IOC_GETVERSION:
2361 			error = file_has_perm(current, file, FILE__GETATTR);
2362 			break;
2363 
2364 		case EXT2_IOC_SETFLAGS:
2365 		/* fall through */
2366 		case EXT2_IOC_SETVERSION:
2367 			error = file_has_perm(current, file, FILE__SETATTR);
2368 			break;
2369 
2370 		/* sys_ioctl() checks */
2371 		case FIONBIO:
2372 		/* fall through */
2373 		case FIOASYNC:
2374 			error = file_has_perm(current, file, 0);
2375 			break;
2376 
2377 	        case KDSKBENT:
2378 	        case KDSKBSENT:
2379 			error = task_has_capability(current,CAP_SYS_TTY_CONFIG);
2380 			break;
2381 
2382 		/* default case assumes that the command will go
2383 		 * to the file's ioctl() function.
2384 		 */
2385 		default:
2386 			error = file_has_perm(current, file, FILE__IOCTL);
2387 
2388 	}
2389 	return error;
2390 }
2391 
2392 static int file_map_prot_check(struct file *file, unsigned long prot, int shared)
2393 {
2394 #ifndef CONFIG_PPC32
2395 	if ((prot & PROT_EXEC) && (!file || (!shared && (prot & PROT_WRITE)))) {
2396 		/*
2397 		 * We are making executable an anonymous mapping or a
2398 		 * private file mapping that will also be writable.
2399 		 * This has an additional check.
2400 		 */
2401 		int rc = task_has_perm(current, current, PROCESS__EXECMEM);
2402 		if (rc)
2403 			return rc;
2404 	}
2405 #endif
2406 
2407 	if (file) {
2408 		/* read access is always possible with a mapping */
2409 		u32 av = FILE__READ;
2410 
2411 		/* write access only matters if the mapping is shared */
2412 		if (shared && (prot & PROT_WRITE))
2413 			av |= FILE__WRITE;
2414 
2415 		if (prot & PROT_EXEC)
2416 			av |= FILE__EXECUTE;
2417 
2418 		return file_has_perm(current, file, av);
2419 	}
2420 	return 0;
2421 }
2422 
2423 static int selinux_file_mmap(struct file *file, unsigned long reqprot,
2424 			     unsigned long prot, unsigned long flags)
2425 {
2426 	int rc;
2427 
2428 	rc = secondary_ops->file_mmap(file, reqprot, prot, flags);
2429 	if (rc)
2430 		return rc;
2431 
2432 	if (selinux_checkreqprot)
2433 		prot = reqprot;
2434 
2435 	return file_map_prot_check(file, prot,
2436 				   (flags & MAP_TYPE) == MAP_SHARED);
2437 }
2438 
2439 static int selinux_file_mprotect(struct vm_area_struct *vma,
2440 				 unsigned long reqprot,
2441 				 unsigned long prot)
2442 {
2443 	int rc;
2444 
2445 	rc = secondary_ops->file_mprotect(vma, reqprot, prot);
2446 	if (rc)
2447 		return rc;
2448 
2449 	if (selinux_checkreqprot)
2450 		prot = reqprot;
2451 
2452 #ifndef CONFIG_PPC32
2453 	if ((prot & PROT_EXEC) && !(vma->vm_flags & VM_EXECUTABLE) &&
2454 	   (vma->vm_start >= vma->vm_mm->start_brk &&
2455 	    vma->vm_end <= vma->vm_mm->brk)) {
2456 	    	/*
2457 		 * We are making an executable mapping in the brk region.
2458 		 * This has an additional execheap check.
2459 		 */
2460 		rc = task_has_perm(current, current, PROCESS__EXECHEAP);
2461 		if (rc)
2462 			return rc;
2463 	}
2464 	if (vma->vm_file != NULL && vma->anon_vma != NULL && (prot & PROT_EXEC)) {
2465 		/*
2466 		 * We are making executable a file mapping that has
2467 		 * had some COW done. Since pages might have been written,
2468 		 * check ability to execute the possibly modified content.
2469 		 * This typically should only occur for text relocations.
2470 		 */
2471 		int rc = file_has_perm(current, vma->vm_file, FILE__EXECMOD);
2472 		if (rc)
2473 			return rc;
2474 	}
2475 	if (!vma->vm_file && (prot & PROT_EXEC) &&
2476 		vma->vm_start <= vma->vm_mm->start_stack &&
2477 		vma->vm_end >= vma->vm_mm->start_stack) {
2478 		/* Attempt to make the process stack executable.
2479 		 * This has an additional execstack check.
2480 		 */
2481 		rc = task_has_perm(current, current, PROCESS__EXECSTACK);
2482 		if (rc)
2483 			return rc;
2484 	}
2485 #endif
2486 
2487 	return file_map_prot_check(vma->vm_file, prot, vma->vm_flags&VM_SHARED);
2488 }
2489 
2490 static int selinux_file_lock(struct file *file, unsigned int cmd)
2491 {
2492 	return file_has_perm(current, file, FILE__LOCK);
2493 }
2494 
2495 static int selinux_file_fcntl(struct file *file, unsigned int cmd,
2496 			      unsigned long arg)
2497 {
2498 	int err = 0;
2499 
2500 	switch (cmd) {
2501 	        case F_SETFL:
2502 			if (!file->f_dentry || !file->f_dentry->d_inode) {
2503 				err = -EINVAL;
2504 				break;
2505 			}
2506 
2507 			if ((file->f_flags & O_APPEND) && !(arg & O_APPEND)) {
2508 				err = file_has_perm(current, file,FILE__WRITE);
2509 				break;
2510 			}
2511 			/* fall through */
2512 	        case F_SETOWN:
2513 	        case F_SETSIG:
2514 	        case F_GETFL:
2515 	        case F_GETOWN:
2516 	        case F_GETSIG:
2517 			/* Just check FD__USE permission */
2518 			err = file_has_perm(current, file, 0);
2519 			break;
2520 		case F_GETLK:
2521 		case F_SETLK:
2522 	        case F_SETLKW:
2523 #if BITS_PER_LONG == 32
2524 	        case F_GETLK64:
2525 		case F_SETLK64:
2526 	        case F_SETLKW64:
2527 #endif
2528 			if (!file->f_dentry || !file->f_dentry->d_inode) {
2529 				err = -EINVAL;
2530 				break;
2531 			}
2532 			err = file_has_perm(current, file, FILE__LOCK);
2533 			break;
2534 	}
2535 
2536 	return err;
2537 }
2538 
2539 static int selinux_file_set_fowner(struct file *file)
2540 {
2541 	struct task_security_struct *tsec;
2542 	struct file_security_struct *fsec;
2543 
2544 	tsec = current->security;
2545 	fsec = file->f_security;
2546 	fsec->fown_sid = tsec->sid;
2547 
2548 	return 0;
2549 }
2550 
2551 static int selinux_file_send_sigiotask(struct task_struct *tsk,
2552 				       struct fown_struct *fown, int signum)
2553 {
2554         struct file *file;
2555 	u32 perm;
2556 	struct task_security_struct *tsec;
2557 	struct file_security_struct *fsec;
2558 
2559 	/* struct fown_struct is never outside the context of a struct file */
2560         file = (struct file *)((long)fown - offsetof(struct file,f_owner));
2561 
2562 	tsec = tsk->security;
2563 	fsec = file->f_security;
2564 
2565 	if (!signum)
2566 		perm = signal_to_av(SIGIO); /* as per send_sigio_to_task */
2567 	else
2568 		perm = signal_to_av(signum);
2569 
2570 	return avc_has_perm(fsec->fown_sid, tsec->sid,
2571 			    SECCLASS_PROCESS, perm, NULL);
2572 }
2573 
2574 static int selinux_file_receive(struct file *file)
2575 {
2576 	return file_has_perm(current, file, file_to_av(file));
2577 }
2578 
2579 /* task security operations */
2580 
2581 static int selinux_task_create(unsigned long clone_flags)
2582 {
2583 	int rc;
2584 
2585 	rc = secondary_ops->task_create(clone_flags);
2586 	if (rc)
2587 		return rc;
2588 
2589 	return task_has_perm(current, current, PROCESS__FORK);
2590 }
2591 
2592 static int selinux_task_alloc_security(struct task_struct *tsk)
2593 {
2594 	struct task_security_struct *tsec1, *tsec2;
2595 	int rc;
2596 
2597 	tsec1 = current->security;
2598 
2599 	rc = task_alloc_security(tsk);
2600 	if (rc)
2601 		return rc;
2602 	tsec2 = tsk->security;
2603 
2604 	tsec2->osid = tsec1->osid;
2605 	tsec2->sid = tsec1->sid;
2606 
2607 	/* Retain the exec and create SIDs across fork */
2608 	tsec2->exec_sid = tsec1->exec_sid;
2609 	tsec2->create_sid = tsec1->create_sid;
2610 
2611 	/* Retain ptracer SID across fork, if any.
2612 	   This will be reset by the ptrace hook upon any
2613 	   subsequent ptrace_attach operations. */
2614 	tsec2->ptrace_sid = tsec1->ptrace_sid;
2615 
2616 	return 0;
2617 }
2618 
2619 static void selinux_task_free_security(struct task_struct *tsk)
2620 {
2621 	task_free_security(tsk);
2622 }
2623 
2624 static int selinux_task_setuid(uid_t id0, uid_t id1, uid_t id2, int flags)
2625 {
2626 	/* Since setuid only affects the current process, and
2627 	   since the SELinux controls are not based on the Linux
2628 	   identity attributes, SELinux does not need to control
2629 	   this operation.  However, SELinux does control the use
2630 	   of the CAP_SETUID and CAP_SETGID capabilities using the
2631 	   capable hook. */
2632 	return 0;
2633 }
2634 
2635 static int selinux_task_post_setuid(uid_t id0, uid_t id1, uid_t id2, int flags)
2636 {
2637 	return secondary_ops->task_post_setuid(id0,id1,id2,flags);
2638 }
2639 
2640 static int selinux_task_setgid(gid_t id0, gid_t id1, gid_t id2, int flags)
2641 {
2642 	/* See the comment for setuid above. */
2643 	return 0;
2644 }
2645 
2646 static int selinux_task_setpgid(struct task_struct *p, pid_t pgid)
2647 {
2648 	return task_has_perm(current, p, PROCESS__SETPGID);
2649 }
2650 
2651 static int selinux_task_getpgid(struct task_struct *p)
2652 {
2653 	return task_has_perm(current, p, PROCESS__GETPGID);
2654 }
2655 
2656 static int selinux_task_getsid(struct task_struct *p)
2657 {
2658 	return task_has_perm(current, p, PROCESS__GETSESSION);
2659 }
2660 
2661 static int selinux_task_setgroups(struct group_info *group_info)
2662 {
2663 	/* See the comment for setuid above. */
2664 	return 0;
2665 }
2666 
2667 static int selinux_task_setnice(struct task_struct *p, int nice)
2668 {
2669 	int rc;
2670 
2671 	rc = secondary_ops->task_setnice(p, nice);
2672 	if (rc)
2673 		return rc;
2674 
2675 	return task_has_perm(current,p, PROCESS__SETSCHED);
2676 }
2677 
2678 static int selinux_task_setrlimit(unsigned int resource, struct rlimit *new_rlim)
2679 {
2680 	struct rlimit *old_rlim = current->signal->rlim + resource;
2681 	int rc;
2682 
2683 	rc = secondary_ops->task_setrlimit(resource, new_rlim);
2684 	if (rc)
2685 		return rc;
2686 
2687 	/* Control the ability to change the hard limit (whether
2688 	   lowering or raising it), so that the hard limit can
2689 	   later be used as a safe reset point for the soft limit
2690 	   upon context transitions. See selinux_bprm_apply_creds. */
2691 	if (old_rlim->rlim_max != new_rlim->rlim_max)
2692 		return task_has_perm(current, current, PROCESS__SETRLIMIT);
2693 
2694 	return 0;
2695 }
2696 
2697 static int selinux_task_setscheduler(struct task_struct *p, int policy, struct sched_param *lp)
2698 {
2699 	return task_has_perm(current, p, PROCESS__SETSCHED);
2700 }
2701 
2702 static int selinux_task_getscheduler(struct task_struct *p)
2703 {
2704 	return task_has_perm(current, p, PROCESS__GETSCHED);
2705 }
2706 
2707 static int selinux_task_kill(struct task_struct *p, struct siginfo *info, int sig)
2708 {
2709 	u32 perm;
2710 	int rc;
2711 
2712 	rc = secondary_ops->task_kill(p, info, sig);
2713 	if (rc)
2714 		return rc;
2715 
2716 	if (info != SEND_SIG_NOINFO && (is_si_special(info) || SI_FROMKERNEL(info)))
2717 		return 0;
2718 
2719 	if (!sig)
2720 		perm = PROCESS__SIGNULL; /* null signal; existence test */
2721 	else
2722 		perm = signal_to_av(sig);
2723 
2724 	return task_has_perm(current, p, perm);
2725 }
2726 
2727 static int selinux_task_prctl(int option,
2728 			      unsigned long arg2,
2729 			      unsigned long arg3,
2730 			      unsigned long arg4,
2731 			      unsigned long arg5)
2732 {
2733 	/* The current prctl operations do not appear to require
2734 	   any SELinux controls since they merely observe or modify
2735 	   the state of the current process. */
2736 	return 0;
2737 }
2738 
2739 static int selinux_task_wait(struct task_struct *p)
2740 {
2741 	u32 perm;
2742 
2743 	perm = signal_to_av(p->exit_signal);
2744 
2745 	return task_has_perm(p, current, perm);
2746 }
2747 
2748 static void selinux_task_reparent_to_init(struct task_struct *p)
2749 {
2750   	struct task_security_struct *tsec;
2751 
2752 	secondary_ops->task_reparent_to_init(p);
2753 
2754 	tsec = p->security;
2755 	tsec->osid = tsec->sid;
2756 	tsec->sid = SECINITSID_KERNEL;
2757 	return;
2758 }
2759 
2760 static void selinux_task_to_inode(struct task_struct *p,
2761 				  struct inode *inode)
2762 {
2763 	struct task_security_struct *tsec = p->security;
2764 	struct inode_security_struct *isec = inode->i_security;
2765 
2766 	isec->sid = tsec->sid;
2767 	isec->initialized = 1;
2768 	return;
2769 }
2770 
2771 #ifdef CONFIG_SECURITY_NETWORK
2772 
2773 /* Returns error only if unable to parse addresses */
2774 static int selinux_parse_skb_ipv4(struct sk_buff *skb, struct avc_audit_data *ad)
2775 {
2776 	int offset, ihlen, ret = -EINVAL;
2777 	struct iphdr _iph, *ih;
2778 
2779 	offset = skb->nh.raw - skb->data;
2780 	ih = skb_header_pointer(skb, offset, sizeof(_iph), &_iph);
2781 	if (ih == NULL)
2782 		goto out;
2783 
2784 	ihlen = ih->ihl * 4;
2785 	if (ihlen < sizeof(_iph))
2786 		goto out;
2787 
2788 	ad->u.net.v4info.saddr = ih->saddr;
2789 	ad->u.net.v4info.daddr = ih->daddr;
2790 	ret = 0;
2791 
2792 	switch (ih->protocol) {
2793         case IPPROTO_TCP: {
2794         	struct tcphdr _tcph, *th;
2795 
2796         	if (ntohs(ih->frag_off) & IP_OFFSET)
2797         		break;
2798 
2799 		offset += ihlen;
2800 		th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph);
2801 		if (th == NULL)
2802 			break;
2803 
2804 		ad->u.net.sport = th->source;
2805 		ad->u.net.dport = th->dest;
2806 		break;
2807         }
2808 
2809         case IPPROTO_UDP: {
2810         	struct udphdr _udph, *uh;
2811 
2812         	if (ntohs(ih->frag_off) & IP_OFFSET)
2813         		break;
2814 
2815 		offset += ihlen;
2816         	uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph);
2817 		if (uh == NULL)
2818 			break;
2819 
2820         	ad->u.net.sport = uh->source;
2821         	ad->u.net.dport = uh->dest;
2822         	break;
2823         }
2824 
2825         default:
2826         	break;
2827         }
2828 out:
2829 	return ret;
2830 }
2831 
2832 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
2833 
2834 /* Returns error only if unable to parse addresses */
2835 static int selinux_parse_skb_ipv6(struct sk_buff *skb, struct avc_audit_data *ad)
2836 {
2837 	u8 nexthdr;
2838 	int ret = -EINVAL, offset;
2839 	struct ipv6hdr _ipv6h, *ip6;
2840 
2841 	offset = skb->nh.raw - skb->data;
2842 	ip6 = skb_header_pointer(skb, offset, sizeof(_ipv6h), &_ipv6h);
2843 	if (ip6 == NULL)
2844 		goto out;
2845 
2846 	ipv6_addr_copy(&ad->u.net.v6info.saddr, &ip6->saddr);
2847 	ipv6_addr_copy(&ad->u.net.v6info.daddr, &ip6->daddr);
2848 	ret = 0;
2849 
2850 	nexthdr = ip6->nexthdr;
2851 	offset += sizeof(_ipv6h);
2852 	offset = ipv6_skip_exthdr(skb, offset, &nexthdr);
2853 	if (offset < 0)
2854 		goto out;
2855 
2856 	switch (nexthdr) {
2857 	case IPPROTO_TCP: {
2858         	struct tcphdr _tcph, *th;
2859 
2860 		th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph);
2861 		if (th == NULL)
2862 			break;
2863 
2864 		ad->u.net.sport = th->source;
2865 		ad->u.net.dport = th->dest;
2866 		break;
2867 	}
2868 
2869 	case IPPROTO_UDP: {
2870 		struct udphdr _udph, *uh;
2871 
2872 		uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph);
2873 		if (uh == NULL)
2874 			break;
2875 
2876 		ad->u.net.sport = uh->source;
2877 		ad->u.net.dport = uh->dest;
2878 		break;
2879 	}
2880 
2881 	/* includes fragments */
2882 	default:
2883 		break;
2884 	}
2885 out:
2886 	return ret;
2887 }
2888 
2889 #endif /* IPV6 */
2890 
2891 static int selinux_parse_skb(struct sk_buff *skb, struct avc_audit_data *ad,
2892 			     char **addrp, int *len, int src)
2893 {
2894 	int ret = 0;
2895 
2896 	switch (ad->u.net.family) {
2897 	case PF_INET:
2898 		ret = selinux_parse_skb_ipv4(skb, ad);
2899 		if (ret || !addrp)
2900 			break;
2901 		*len = 4;
2902 		*addrp = (char *)(src ? &ad->u.net.v4info.saddr :
2903 					&ad->u.net.v4info.daddr);
2904 		break;
2905 
2906 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
2907 	case PF_INET6:
2908 		ret = selinux_parse_skb_ipv6(skb, ad);
2909 		if (ret || !addrp)
2910 			break;
2911 		*len = 16;
2912 		*addrp = (char *)(src ? &ad->u.net.v6info.saddr :
2913 					&ad->u.net.v6info.daddr);
2914 		break;
2915 #endif	/* IPV6 */
2916 	default:
2917 		break;
2918 	}
2919 
2920 	return ret;
2921 }
2922 
2923 /* socket security operations */
2924 static int socket_has_perm(struct task_struct *task, struct socket *sock,
2925 			   u32 perms)
2926 {
2927 	struct inode_security_struct *isec;
2928 	struct task_security_struct *tsec;
2929 	struct avc_audit_data ad;
2930 	int err = 0;
2931 
2932 	tsec = task->security;
2933 	isec = SOCK_INODE(sock)->i_security;
2934 
2935 	if (isec->sid == SECINITSID_KERNEL)
2936 		goto out;
2937 
2938 	AVC_AUDIT_DATA_INIT(&ad,NET);
2939 	ad.u.net.sk = sock->sk;
2940 	err = avc_has_perm(tsec->sid, isec->sid, isec->sclass, perms, &ad);
2941 
2942 out:
2943 	return err;
2944 }
2945 
2946 static int selinux_socket_create(int family, int type,
2947 				 int protocol, int kern)
2948 {
2949 	int err = 0;
2950 	struct task_security_struct *tsec;
2951 
2952 	if (kern)
2953 		goto out;
2954 
2955 	tsec = current->security;
2956 	err = avc_has_perm(tsec->sid, tsec->sid,
2957 			   socket_type_to_security_class(family, type,
2958 			   protocol), SOCKET__CREATE, NULL);
2959 
2960 out:
2961 	return err;
2962 }
2963 
2964 static void selinux_socket_post_create(struct socket *sock, int family,
2965 				       int type, int protocol, int kern)
2966 {
2967 	struct inode_security_struct *isec;
2968 	struct task_security_struct *tsec;
2969 
2970 	isec = SOCK_INODE(sock)->i_security;
2971 
2972 	tsec = current->security;
2973 	isec->sclass = socket_type_to_security_class(family, type, protocol);
2974 	isec->sid = kern ? SECINITSID_KERNEL : tsec->sid;
2975 	isec->initialized = 1;
2976 
2977 	return;
2978 }
2979 
2980 /* Range of port numbers used to automatically bind.
2981    Need to determine whether we should perform a name_bind
2982    permission check between the socket and the port number. */
2983 #define ip_local_port_range_0 sysctl_local_port_range[0]
2984 #define ip_local_port_range_1 sysctl_local_port_range[1]
2985 
2986 static int selinux_socket_bind(struct socket *sock, struct sockaddr *address, int addrlen)
2987 {
2988 	u16 family;
2989 	int err;
2990 
2991 	err = socket_has_perm(current, sock, SOCKET__BIND);
2992 	if (err)
2993 		goto out;
2994 
2995 	/*
2996 	 * If PF_INET or PF_INET6, check name_bind permission for the port.
2997 	 * Multiple address binding for SCTP is not supported yet: we just
2998 	 * check the first address now.
2999 	 */
3000 	family = sock->sk->sk_family;
3001 	if (family == PF_INET || family == PF_INET6) {
3002 		char *addrp;
3003 		struct inode_security_struct *isec;
3004 		struct task_security_struct *tsec;
3005 		struct avc_audit_data ad;
3006 		struct sockaddr_in *addr4 = NULL;
3007 		struct sockaddr_in6 *addr6 = NULL;
3008 		unsigned short snum;
3009 		struct sock *sk = sock->sk;
3010 		u32 sid, node_perm, addrlen;
3011 
3012 		tsec = current->security;
3013 		isec = SOCK_INODE(sock)->i_security;
3014 
3015 		if (family == PF_INET) {
3016 			addr4 = (struct sockaddr_in *)address;
3017 			snum = ntohs(addr4->sin_port);
3018 			addrlen = sizeof(addr4->sin_addr.s_addr);
3019 			addrp = (char *)&addr4->sin_addr.s_addr;
3020 		} else {
3021 			addr6 = (struct sockaddr_in6 *)address;
3022 			snum = ntohs(addr6->sin6_port);
3023 			addrlen = sizeof(addr6->sin6_addr.s6_addr);
3024 			addrp = (char *)&addr6->sin6_addr.s6_addr;
3025 		}
3026 
3027 		if (snum&&(snum < max(PROT_SOCK,ip_local_port_range_0) ||
3028 			   snum > ip_local_port_range_1)) {
3029 			err = security_port_sid(sk->sk_family, sk->sk_type,
3030 						sk->sk_protocol, snum, &sid);
3031 			if (err)
3032 				goto out;
3033 			AVC_AUDIT_DATA_INIT(&ad,NET);
3034 			ad.u.net.sport = htons(snum);
3035 			ad.u.net.family = family;
3036 			err = avc_has_perm(isec->sid, sid,
3037 					   isec->sclass,
3038 					   SOCKET__NAME_BIND, &ad);
3039 			if (err)
3040 				goto out;
3041 		}
3042 
3043 		switch(isec->sclass) {
3044 		case SECCLASS_TCP_SOCKET:
3045 			node_perm = TCP_SOCKET__NODE_BIND;
3046 			break;
3047 
3048 		case SECCLASS_UDP_SOCKET:
3049 			node_perm = UDP_SOCKET__NODE_BIND;
3050 			break;
3051 
3052 		default:
3053 			node_perm = RAWIP_SOCKET__NODE_BIND;
3054 			break;
3055 		}
3056 
3057 		err = security_node_sid(family, addrp, addrlen, &sid);
3058 		if (err)
3059 			goto out;
3060 
3061 		AVC_AUDIT_DATA_INIT(&ad,NET);
3062 		ad.u.net.sport = htons(snum);
3063 		ad.u.net.family = family;
3064 
3065 		if (family == PF_INET)
3066 			ad.u.net.v4info.saddr = addr4->sin_addr.s_addr;
3067 		else
3068 			ipv6_addr_copy(&ad.u.net.v6info.saddr, &addr6->sin6_addr);
3069 
3070 		err = avc_has_perm(isec->sid, sid,
3071 		                   isec->sclass, node_perm, &ad);
3072 		if (err)
3073 			goto out;
3074 	}
3075 out:
3076 	return err;
3077 }
3078 
3079 static int selinux_socket_connect(struct socket *sock, struct sockaddr *address, int addrlen)
3080 {
3081 	struct inode_security_struct *isec;
3082 	int err;
3083 
3084 	err = socket_has_perm(current, sock, SOCKET__CONNECT);
3085 	if (err)
3086 		return err;
3087 
3088 	/*
3089 	 * If a TCP socket, check name_connect permission for the port.
3090 	 */
3091 	isec = SOCK_INODE(sock)->i_security;
3092 	if (isec->sclass == SECCLASS_TCP_SOCKET) {
3093 		struct sock *sk = sock->sk;
3094 		struct avc_audit_data ad;
3095 		struct sockaddr_in *addr4 = NULL;
3096 		struct sockaddr_in6 *addr6 = NULL;
3097 		unsigned short snum;
3098 		u32 sid;
3099 
3100 		if (sk->sk_family == PF_INET) {
3101 			addr4 = (struct sockaddr_in *)address;
3102 			if (addrlen < sizeof(struct sockaddr_in))
3103 				return -EINVAL;
3104 			snum = ntohs(addr4->sin_port);
3105 		} else {
3106 			addr6 = (struct sockaddr_in6 *)address;
3107 			if (addrlen < SIN6_LEN_RFC2133)
3108 				return -EINVAL;
3109 			snum = ntohs(addr6->sin6_port);
3110 		}
3111 
3112 		err = security_port_sid(sk->sk_family, sk->sk_type,
3113 					sk->sk_protocol, snum, &sid);
3114 		if (err)
3115 			goto out;
3116 
3117 		AVC_AUDIT_DATA_INIT(&ad,NET);
3118 		ad.u.net.dport = htons(snum);
3119 		ad.u.net.family = sk->sk_family;
3120 		err = avc_has_perm(isec->sid, sid, isec->sclass,
3121 				   TCP_SOCKET__NAME_CONNECT, &ad);
3122 		if (err)
3123 			goto out;
3124 	}
3125 
3126 out:
3127 	return err;
3128 }
3129 
3130 static int selinux_socket_listen(struct socket *sock, int backlog)
3131 {
3132 	return socket_has_perm(current, sock, SOCKET__LISTEN);
3133 }
3134 
3135 static int selinux_socket_accept(struct socket *sock, struct socket *newsock)
3136 {
3137 	int err;
3138 	struct inode_security_struct *isec;
3139 	struct inode_security_struct *newisec;
3140 
3141 	err = socket_has_perm(current, sock, SOCKET__ACCEPT);
3142 	if (err)
3143 		return err;
3144 
3145 	newisec = SOCK_INODE(newsock)->i_security;
3146 
3147 	isec = SOCK_INODE(sock)->i_security;
3148 	newisec->sclass = isec->sclass;
3149 	newisec->sid = isec->sid;
3150 	newisec->initialized = 1;
3151 
3152 	return 0;
3153 }
3154 
3155 static int selinux_socket_sendmsg(struct socket *sock, struct msghdr *msg,
3156  				  int size)
3157 {
3158 	return socket_has_perm(current, sock, SOCKET__WRITE);
3159 }
3160 
3161 static int selinux_socket_recvmsg(struct socket *sock, struct msghdr *msg,
3162 				  int size, int flags)
3163 {
3164 	return socket_has_perm(current, sock, SOCKET__READ);
3165 }
3166 
3167 static int selinux_socket_getsockname(struct socket *sock)
3168 {
3169 	return socket_has_perm(current, sock, SOCKET__GETATTR);
3170 }
3171 
3172 static int selinux_socket_getpeername(struct socket *sock)
3173 {
3174 	return socket_has_perm(current, sock, SOCKET__GETATTR);
3175 }
3176 
3177 static int selinux_socket_setsockopt(struct socket *sock,int level,int optname)
3178 {
3179 	return socket_has_perm(current, sock, SOCKET__SETOPT);
3180 }
3181 
3182 static int selinux_socket_getsockopt(struct socket *sock, int level,
3183 				     int optname)
3184 {
3185 	return socket_has_perm(current, sock, SOCKET__GETOPT);
3186 }
3187 
3188 static int selinux_socket_shutdown(struct socket *sock, int how)
3189 {
3190 	return socket_has_perm(current, sock, SOCKET__SHUTDOWN);
3191 }
3192 
3193 static int selinux_socket_unix_stream_connect(struct socket *sock,
3194 					      struct socket *other,
3195 					      struct sock *newsk)
3196 {
3197 	struct sk_security_struct *ssec;
3198 	struct inode_security_struct *isec;
3199 	struct inode_security_struct *other_isec;
3200 	struct avc_audit_data ad;
3201 	int err;
3202 
3203 	err = secondary_ops->unix_stream_connect(sock, other, newsk);
3204 	if (err)
3205 		return err;
3206 
3207 	isec = SOCK_INODE(sock)->i_security;
3208 	other_isec = SOCK_INODE(other)->i_security;
3209 
3210 	AVC_AUDIT_DATA_INIT(&ad,NET);
3211 	ad.u.net.sk = other->sk;
3212 
3213 	err = avc_has_perm(isec->sid, other_isec->sid,
3214 			   isec->sclass,
3215 			   UNIX_STREAM_SOCKET__CONNECTTO, &ad);
3216 	if (err)
3217 		return err;
3218 
3219 	/* connecting socket */
3220 	ssec = sock->sk->sk_security;
3221 	ssec->peer_sid = other_isec->sid;
3222 
3223 	/* server child socket */
3224 	ssec = newsk->sk_security;
3225 	ssec->peer_sid = isec->sid;
3226 
3227 	return 0;
3228 }
3229 
3230 static int selinux_socket_unix_may_send(struct socket *sock,
3231 					struct socket *other)
3232 {
3233 	struct inode_security_struct *isec;
3234 	struct inode_security_struct *other_isec;
3235 	struct avc_audit_data ad;
3236 	int err;
3237 
3238 	isec = SOCK_INODE(sock)->i_security;
3239 	other_isec = SOCK_INODE(other)->i_security;
3240 
3241 	AVC_AUDIT_DATA_INIT(&ad,NET);
3242 	ad.u.net.sk = other->sk;
3243 
3244 	err = avc_has_perm(isec->sid, other_isec->sid,
3245 			   isec->sclass, SOCKET__SENDTO, &ad);
3246 	if (err)
3247 		return err;
3248 
3249 	return 0;
3250 }
3251 
3252 static int selinux_socket_sock_rcv_skb(struct sock *sk, struct sk_buff *skb)
3253 {
3254 	u16 family;
3255 	char *addrp;
3256 	int len, err = 0;
3257 	u32 netif_perm, node_perm, node_sid, if_sid, recv_perm = 0;
3258 	u32 sock_sid = 0;
3259 	u16 sock_class = 0;
3260 	struct socket *sock;
3261 	struct net_device *dev;
3262 	struct avc_audit_data ad;
3263 
3264 	family = sk->sk_family;
3265 	if (family != PF_INET && family != PF_INET6)
3266 		goto out;
3267 
3268 	/* Handle mapped IPv4 packets arriving via IPv6 sockets */
3269 	if (family == PF_INET6 && skb->protocol == ntohs(ETH_P_IP))
3270 		family = PF_INET;
3271 
3272  	read_lock_bh(&sk->sk_callback_lock);
3273  	sock = sk->sk_socket;
3274  	if (sock) {
3275  		struct inode *inode;
3276  		inode = SOCK_INODE(sock);
3277  		if (inode) {
3278  			struct inode_security_struct *isec;
3279  			isec = inode->i_security;
3280  			sock_sid = isec->sid;
3281  			sock_class = isec->sclass;
3282  		}
3283  	}
3284  	read_unlock_bh(&sk->sk_callback_lock);
3285  	if (!sock_sid)
3286   		goto out;
3287 
3288 	dev = skb->dev;
3289 	if (!dev)
3290 		goto out;
3291 
3292 	err = sel_netif_sids(dev, &if_sid, NULL);
3293 	if (err)
3294 		goto out;
3295 
3296 	switch (sock_class) {
3297 	case SECCLASS_UDP_SOCKET:
3298 		netif_perm = NETIF__UDP_RECV;
3299 		node_perm = NODE__UDP_RECV;
3300 		recv_perm = UDP_SOCKET__RECV_MSG;
3301 		break;
3302 
3303 	case SECCLASS_TCP_SOCKET:
3304 		netif_perm = NETIF__TCP_RECV;
3305 		node_perm = NODE__TCP_RECV;
3306 		recv_perm = TCP_SOCKET__RECV_MSG;
3307 		break;
3308 
3309 	default:
3310 		netif_perm = NETIF__RAWIP_RECV;
3311 		node_perm = NODE__RAWIP_RECV;
3312 		break;
3313 	}
3314 
3315 	AVC_AUDIT_DATA_INIT(&ad, NET);
3316 	ad.u.net.netif = dev->name;
3317 	ad.u.net.family = family;
3318 
3319 	err = selinux_parse_skb(skb, &ad, &addrp, &len, 1);
3320 	if (err)
3321 		goto out;
3322 
3323 	err = avc_has_perm(sock_sid, if_sid, SECCLASS_NETIF, netif_perm, &ad);
3324 	if (err)
3325 		goto out;
3326 
3327 	/* Fixme: this lookup is inefficient */
3328 	err = security_node_sid(family, addrp, len, &node_sid);
3329 	if (err)
3330 		goto out;
3331 
3332 	err = avc_has_perm(sock_sid, node_sid, SECCLASS_NODE, node_perm, &ad);
3333 	if (err)
3334 		goto out;
3335 
3336 	if (recv_perm) {
3337 		u32 port_sid;
3338 
3339 		/* Fixme: make this more efficient */
3340 		err = security_port_sid(sk->sk_family, sk->sk_type,
3341 		                        sk->sk_protocol, ntohs(ad.u.net.sport),
3342 		                        &port_sid);
3343 		if (err)
3344 			goto out;
3345 
3346 		err = avc_has_perm(sock_sid, port_sid,
3347 				   sock_class, recv_perm, &ad);
3348 	}
3349 out:
3350 	return err;
3351 }
3352 
3353 static int selinux_socket_getpeersec(struct socket *sock, char __user *optval,
3354 				     int __user *optlen, unsigned len)
3355 {
3356 	int err = 0;
3357 	char *scontext;
3358 	u32 scontext_len;
3359 	struct sk_security_struct *ssec;
3360 	struct inode_security_struct *isec;
3361 
3362 	isec = SOCK_INODE(sock)->i_security;
3363 	if (isec->sclass != SECCLASS_UNIX_STREAM_SOCKET) {
3364 		err = -ENOPROTOOPT;
3365 		goto out;
3366 	}
3367 
3368 	ssec = sock->sk->sk_security;
3369 
3370 	err = security_sid_to_context(ssec->peer_sid, &scontext, &scontext_len);
3371 	if (err)
3372 		goto out;
3373 
3374 	if (scontext_len > len) {
3375 		err = -ERANGE;
3376 		goto out_len;
3377 	}
3378 
3379 	if (copy_to_user(optval, scontext, scontext_len))
3380 		err = -EFAULT;
3381 
3382 out_len:
3383 	if (put_user(scontext_len, optlen))
3384 		err = -EFAULT;
3385 
3386 	kfree(scontext);
3387 out:
3388 	return err;
3389 }
3390 
3391 static int selinux_sk_alloc_security(struct sock *sk, int family, gfp_t priority)
3392 {
3393 	return sk_alloc_security(sk, family, priority);
3394 }
3395 
3396 static void selinux_sk_free_security(struct sock *sk)
3397 {
3398 	sk_free_security(sk);
3399 }
3400 
3401 static int selinux_nlmsg_perm(struct sock *sk, struct sk_buff *skb)
3402 {
3403 	int err = 0;
3404 	u32 perm;
3405 	struct nlmsghdr *nlh;
3406 	struct socket *sock = sk->sk_socket;
3407 	struct inode_security_struct *isec = SOCK_INODE(sock)->i_security;
3408 
3409 	if (skb->len < NLMSG_SPACE(0)) {
3410 		err = -EINVAL;
3411 		goto out;
3412 	}
3413 	nlh = (struct nlmsghdr *)skb->data;
3414 
3415 	err = selinux_nlmsg_lookup(isec->sclass, nlh->nlmsg_type, &perm);
3416 	if (err) {
3417 		if (err == -EINVAL) {
3418 			audit_log(current->audit_context, GFP_KERNEL, AUDIT_SELINUX_ERR,
3419 				  "SELinux:  unrecognized netlink message"
3420 				  " type=%hu for sclass=%hu\n",
3421 				  nlh->nlmsg_type, isec->sclass);
3422 			if (!selinux_enforcing)
3423 				err = 0;
3424 		}
3425 
3426 		/* Ignore */
3427 		if (err == -ENOENT)
3428 			err = 0;
3429 		goto out;
3430 	}
3431 
3432 	err = socket_has_perm(current, sock, perm);
3433 out:
3434 	return err;
3435 }
3436 
3437 #ifdef CONFIG_NETFILTER
3438 
3439 static unsigned int selinux_ip_postroute_last(unsigned int hooknum,
3440                                               struct sk_buff **pskb,
3441                                               const struct net_device *in,
3442                                               const struct net_device *out,
3443                                               int (*okfn)(struct sk_buff *),
3444                                               u16 family)
3445 {
3446 	char *addrp;
3447 	int len, err = NF_ACCEPT;
3448 	u32 netif_perm, node_perm, node_sid, if_sid, send_perm = 0;
3449 	struct sock *sk;
3450 	struct socket *sock;
3451 	struct inode *inode;
3452 	struct sk_buff *skb = *pskb;
3453 	struct inode_security_struct *isec;
3454 	struct avc_audit_data ad;
3455 	struct net_device *dev = (struct net_device *)out;
3456 
3457 	sk = skb->sk;
3458 	if (!sk)
3459 		goto out;
3460 
3461 	sock = sk->sk_socket;
3462 	if (!sock)
3463 		goto out;
3464 
3465 	inode = SOCK_INODE(sock);
3466 	if (!inode)
3467 		goto out;
3468 
3469 	err = sel_netif_sids(dev, &if_sid, NULL);
3470 	if (err)
3471 		goto out;
3472 
3473 	isec = inode->i_security;
3474 
3475 	switch (isec->sclass) {
3476 	case SECCLASS_UDP_SOCKET:
3477 		netif_perm = NETIF__UDP_SEND;
3478 		node_perm = NODE__UDP_SEND;
3479 		send_perm = UDP_SOCKET__SEND_MSG;
3480 		break;
3481 
3482 	case SECCLASS_TCP_SOCKET:
3483 		netif_perm = NETIF__TCP_SEND;
3484 		node_perm = NODE__TCP_SEND;
3485 		send_perm = TCP_SOCKET__SEND_MSG;
3486 		break;
3487 
3488 	default:
3489 		netif_perm = NETIF__RAWIP_SEND;
3490 		node_perm = NODE__RAWIP_SEND;
3491 		break;
3492 	}
3493 
3494 
3495 	AVC_AUDIT_DATA_INIT(&ad, NET);
3496 	ad.u.net.netif = dev->name;
3497 	ad.u.net.family = family;
3498 
3499 	err = selinux_parse_skb(skb, &ad, &addrp,
3500 				&len, 0) ? NF_DROP : NF_ACCEPT;
3501 	if (err != NF_ACCEPT)
3502 		goto out;
3503 
3504 	err = avc_has_perm(isec->sid, if_sid, SECCLASS_NETIF,
3505 	                   netif_perm, &ad) ? NF_DROP : NF_ACCEPT;
3506 	if (err != NF_ACCEPT)
3507 		goto out;
3508 
3509 	/* Fixme: this lookup is inefficient */
3510 	err = security_node_sid(family, addrp, len,
3511 				&node_sid) ? NF_DROP : NF_ACCEPT;
3512 	if (err != NF_ACCEPT)
3513 		goto out;
3514 
3515 	err = avc_has_perm(isec->sid, node_sid, SECCLASS_NODE,
3516 	                   node_perm, &ad) ? NF_DROP : NF_ACCEPT;
3517 	if (err != NF_ACCEPT)
3518 		goto out;
3519 
3520 	if (send_perm) {
3521 		u32 port_sid;
3522 
3523 		/* Fixme: make this more efficient */
3524 		err = security_port_sid(sk->sk_family,
3525 		                        sk->sk_type,
3526 		                        sk->sk_protocol,
3527 		                        ntohs(ad.u.net.dport),
3528 		                        &port_sid) ? NF_DROP : NF_ACCEPT;
3529 		if (err != NF_ACCEPT)
3530 			goto out;
3531 
3532 		err = avc_has_perm(isec->sid, port_sid, isec->sclass,
3533 		                   send_perm, &ad) ? NF_DROP : NF_ACCEPT;
3534 	}
3535 
3536 out:
3537 	return err;
3538 }
3539 
3540 static unsigned int selinux_ipv4_postroute_last(unsigned int hooknum,
3541 						struct sk_buff **pskb,
3542 						const struct net_device *in,
3543 						const struct net_device *out,
3544 						int (*okfn)(struct sk_buff *))
3545 {
3546 	return selinux_ip_postroute_last(hooknum, pskb, in, out, okfn, PF_INET);
3547 }
3548 
3549 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
3550 
3551 static unsigned int selinux_ipv6_postroute_last(unsigned int hooknum,
3552 						struct sk_buff **pskb,
3553 						const struct net_device *in,
3554 						const struct net_device *out,
3555 						int (*okfn)(struct sk_buff *))
3556 {
3557 	return selinux_ip_postroute_last(hooknum, pskb, in, out, okfn, PF_INET6);
3558 }
3559 
3560 #endif	/* IPV6 */
3561 
3562 #endif	/* CONFIG_NETFILTER */
3563 
3564 #else
3565 
3566 static inline int selinux_nlmsg_perm(struct sock *sk, struct sk_buff *skb)
3567 {
3568 	return 0;
3569 }
3570 
3571 #endif	/* CONFIG_SECURITY_NETWORK */
3572 
3573 static int selinux_netlink_send(struct sock *sk, struct sk_buff *skb)
3574 {
3575 	struct task_security_struct *tsec;
3576 	struct av_decision avd;
3577 	int err;
3578 
3579 	err = secondary_ops->netlink_send(sk, skb);
3580 	if (err)
3581 		return err;
3582 
3583 	tsec = current->security;
3584 
3585 	avd.allowed = 0;
3586 	avc_has_perm_noaudit(tsec->sid, tsec->sid,
3587 				SECCLASS_CAPABILITY, ~0, &avd);
3588 	cap_mask(NETLINK_CB(skb).eff_cap, avd.allowed);
3589 
3590 	if (policydb_loaded_version >= POLICYDB_VERSION_NLCLASS)
3591 		err = selinux_nlmsg_perm(sk, skb);
3592 
3593 	return err;
3594 }
3595 
3596 static int selinux_netlink_recv(struct sk_buff *skb)
3597 {
3598 	if (!cap_raised(NETLINK_CB(skb).eff_cap, CAP_NET_ADMIN))
3599 		return -EPERM;
3600 	return 0;
3601 }
3602 
3603 static int ipc_alloc_security(struct task_struct *task,
3604 			      struct kern_ipc_perm *perm,
3605 			      u16 sclass)
3606 {
3607 	struct task_security_struct *tsec = task->security;
3608 	struct ipc_security_struct *isec;
3609 
3610 	isec = kzalloc(sizeof(struct ipc_security_struct), GFP_KERNEL);
3611 	if (!isec)
3612 		return -ENOMEM;
3613 
3614 	isec->magic = SELINUX_MAGIC;
3615 	isec->sclass = sclass;
3616 	isec->ipc_perm = perm;
3617 	if (tsec) {
3618 		isec->sid = tsec->sid;
3619 	} else {
3620 		isec->sid = SECINITSID_UNLABELED;
3621 	}
3622 	perm->security = isec;
3623 
3624 	return 0;
3625 }
3626 
3627 static void ipc_free_security(struct kern_ipc_perm *perm)
3628 {
3629 	struct ipc_security_struct *isec = perm->security;
3630 	if (!isec || isec->magic != SELINUX_MAGIC)
3631 		return;
3632 
3633 	perm->security = NULL;
3634 	kfree(isec);
3635 }
3636 
3637 static int msg_msg_alloc_security(struct msg_msg *msg)
3638 {
3639 	struct msg_security_struct *msec;
3640 
3641 	msec = kzalloc(sizeof(struct msg_security_struct), GFP_KERNEL);
3642 	if (!msec)
3643 		return -ENOMEM;
3644 
3645 	msec->magic = SELINUX_MAGIC;
3646 	msec->msg = msg;
3647 	msec->sid = SECINITSID_UNLABELED;
3648 	msg->security = msec;
3649 
3650 	return 0;
3651 }
3652 
3653 static void msg_msg_free_security(struct msg_msg *msg)
3654 {
3655 	struct msg_security_struct *msec = msg->security;
3656 	if (!msec || msec->magic != SELINUX_MAGIC)
3657 		return;
3658 
3659 	msg->security = NULL;
3660 	kfree(msec);
3661 }
3662 
3663 static int ipc_has_perm(struct kern_ipc_perm *ipc_perms,
3664 			u32 perms)
3665 {
3666 	struct task_security_struct *tsec;
3667 	struct ipc_security_struct *isec;
3668 	struct avc_audit_data ad;
3669 
3670 	tsec = current->security;
3671 	isec = ipc_perms->security;
3672 
3673 	AVC_AUDIT_DATA_INIT(&ad, IPC);
3674 	ad.u.ipc_id = ipc_perms->key;
3675 
3676 	return avc_has_perm(tsec->sid, isec->sid, isec->sclass, perms, &ad);
3677 }
3678 
3679 static int selinux_msg_msg_alloc_security(struct msg_msg *msg)
3680 {
3681 	return msg_msg_alloc_security(msg);
3682 }
3683 
3684 static void selinux_msg_msg_free_security(struct msg_msg *msg)
3685 {
3686 	msg_msg_free_security(msg);
3687 }
3688 
3689 /* message queue security operations */
3690 static int selinux_msg_queue_alloc_security(struct msg_queue *msq)
3691 {
3692 	struct task_security_struct *tsec;
3693 	struct ipc_security_struct *isec;
3694 	struct avc_audit_data ad;
3695 	int rc;
3696 
3697 	rc = ipc_alloc_security(current, &msq->q_perm, SECCLASS_MSGQ);
3698 	if (rc)
3699 		return rc;
3700 
3701 	tsec = current->security;
3702 	isec = msq->q_perm.security;
3703 
3704 	AVC_AUDIT_DATA_INIT(&ad, IPC);
3705  	ad.u.ipc_id = msq->q_perm.key;
3706 
3707 	rc = avc_has_perm(tsec->sid, isec->sid, SECCLASS_MSGQ,
3708 			  MSGQ__CREATE, &ad);
3709 	if (rc) {
3710 		ipc_free_security(&msq->q_perm);
3711 		return rc;
3712 	}
3713 	return 0;
3714 }
3715 
3716 static void selinux_msg_queue_free_security(struct msg_queue *msq)
3717 {
3718 	ipc_free_security(&msq->q_perm);
3719 }
3720 
3721 static int selinux_msg_queue_associate(struct msg_queue *msq, int msqflg)
3722 {
3723 	struct task_security_struct *tsec;
3724 	struct ipc_security_struct *isec;
3725 	struct avc_audit_data ad;
3726 
3727 	tsec = current->security;
3728 	isec = msq->q_perm.security;
3729 
3730 	AVC_AUDIT_DATA_INIT(&ad, IPC);
3731 	ad.u.ipc_id = msq->q_perm.key;
3732 
3733 	return avc_has_perm(tsec->sid, isec->sid, SECCLASS_MSGQ,
3734 			    MSGQ__ASSOCIATE, &ad);
3735 }
3736 
3737 static int selinux_msg_queue_msgctl(struct msg_queue *msq, int cmd)
3738 {
3739 	int err;
3740 	int perms;
3741 
3742 	switch(cmd) {
3743 	case IPC_INFO:
3744 	case MSG_INFO:
3745 		/* No specific object, just general system-wide information. */
3746 		return task_has_system(current, SYSTEM__IPC_INFO);
3747 	case IPC_STAT:
3748 	case MSG_STAT:
3749 		perms = MSGQ__GETATTR | MSGQ__ASSOCIATE;
3750 		break;
3751 	case IPC_SET:
3752 		perms = MSGQ__SETATTR;
3753 		break;
3754 	case IPC_RMID:
3755 		perms = MSGQ__DESTROY;
3756 		break;
3757 	default:
3758 		return 0;
3759 	}
3760 
3761 	err = ipc_has_perm(&msq->q_perm, perms);
3762 	return err;
3763 }
3764 
3765 static int selinux_msg_queue_msgsnd(struct msg_queue *msq, struct msg_msg *msg, int msqflg)
3766 {
3767 	struct task_security_struct *tsec;
3768 	struct ipc_security_struct *isec;
3769 	struct msg_security_struct *msec;
3770 	struct avc_audit_data ad;
3771 	int rc;
3772 
3773 	tsec = current->security;
3774 	isec = msq->q_perm.security;
3775 	msec = msg->security;
3776 
3777 	/*
3778 	 * First time through, need to assign label to the message
3779 	 */
3780 	if (msec->sid == SECINITSID_UNLABELED) {
3781 		/*
3782 		 * Compute new sid based on current process and
3783 		 * message queue this message will be stored in
3784 		 */
3785 		rc = security_transition_sid(tsec->sid,
3786 					     isec->sid,
3787 					     SECCLASS_MSG,
3788 					     &msec->sid);
3789 		if (rc)
3790 			return rc;
3791 	}
3792 
3793 	AVC_AUDIT_DATA_INIT(&ad, IPC);
3794 	ad.u.ipc_id = msq->q_perm.key;
3795 
3796 	/* Can this process write to the queue? */
3797 	rc = avc_has_perm(tsec->sid, isec->sid, SECCLASS_MSGQ,
3798 			  MSGQ__WRITE, &ad);
3799 	if (!rc)
3800 		/* Can this process send the message */
3801 		rc = avc_has_perm(tsec->sid, msec->sid,
3802 				  SECCLASS_MSG, MSG__SEND, &ad);
3803 	if (!rc)
3804 		/* Can the message be put in the queue? */
3805 		rc = avc_has_perm(msec->sid, isec->sid,
3806 				  SECCLASS_MSGQ, MSGQ__ENQUEUE, &ad);
3807 
3808 	return rc;
3809 }
3810 
3811 static int selinux_msg_queue_msgrcv(struct msg_queue *msq, struct msg_msg *msg,
3812 				    struct task_struct *target,
3813 				    long type, int mode)
3814 {
3815 	struct task_security_struct *tsec;
3816 	struct ipc_security_struct *isec;
3817 	struct msg_security_struct *msec;
3818 	struct avc_audit_data ad;
3819 	int rc;
3820 
3821 	tsec = target->security;
3822 	isec = msq->q_perm.security;
3823 	msec = msg->security;
3824 
3825 	AVC_AUDIT_DATA_INIT(&ad, IPC);
3826  	ad.u.ipc_id = msq->q_perm.key;
3827 
3828 	rc = avc_has_perm(tsec->sid, isec->sid,
3829 			  SECCLASS_MSGQ, MSGQ__READ, &ad);
3830 	if (!rc)
3831 		rc = avc_has_perm(tsec->sid, msec->sid,
3832 				  SECCLASS_MSG, MSG__RECEIVE, &ad);
3833 	return rc;
3834 }
3835 
3836 /* Shared Memory security operations */
3837 static int selinux_shm_alloc_security(struct shmid_kernel *shp)
3838 {
3839 	struct task_security_struct *tsec;
3840 	struct ipc_security_struct *isec;
3841 	struct avc_audit_data ad;
3842 	int rc;
3843 
3844 	rc = ipc_alloc_security(current, &shp->shm_perm, SECCLASS_SHM);
3845 	if (rc)
3846 		return rc;
3847 
3848 	tsec = current->security;
3849 	isec = shp->shm_perm.security;
3850 
3851 	AVC_AUDIT_DATA_INIT(&ad, IPC);
3852  	ad.u.ipc_id = shp->shm_perm.key;
3853 
3854 	rc = avc_has_perm(tsec->sid, isec->sid, SECCLASS_SHM,
3855 			  SHM__CREATE, &ad);
3856 	if (rc) {
3857 		ipc_free_security(&shp->shm_perm);
3858 		return rc;
3859 	}
3860 	return 0;
3861 }
3862 
3863 static void selinux_shm_free_security(struct shmid_kernel *shp)
3864 {
3865 	ipc_free_security(&shp->shm_perm);
3866 }
3867 
3868 static int selinux_shm_associate(struct shmid_kernel *shp, int shmflg)
3869 {
3870 	struct task_security_struct *tsec;
3871 	struct ipc_security_struct *isec;
3872 	struct avc_audit_data ad;
3873 
3874 	tsec = current->security;
3875 	isec = shp->shm_perm.security;
3876 
3877 	AVC_AUDIT_DATA_INIT(&ad, IPC);
3878 	ad.u.ipc_id = shp->shm_perm.key;
3879 
3880 	return avc_has_perm(tsec->sid, isec->sid, SECCLASS_SHM,
3881 			    SHM__ASSOCIATE, &ad);
3882 }
3883 
3884 /* Note, at this point, shp is locked down */
3885 static int selinux_shm_shmctl(struct shmid_kernel *shp, int cmd)
3886 {
3887 	int perms;
3888 	int err;
3889 
3890 	switch(cmd) {
3891 	case IPC_INFO:
3892 	case SHM_INFO:
3893 		/* No specific object, just general system-wide information. */
3894 		return task_has_system(current, SYSTEM__IPC_INFO);
3895 	case IPC_STAT:
3896 	case SHM_STAT:
3897 		perms = SHM__GETATTR | SHM__ASSOCIATE;
3898 		break;
3899 	case IPC_SET:
3900 		perms = SHM__SETATTR;
3901 		break;
3902 	case SHM_LOCK:
3903 	case SHM_UNLOCK:
3904 		perms = SHM__LOCK;
3905 		break;
3906 	case IPC_RMID:
3907 		perms = SHM__DESTROY;
3908 		break;
3909 	default:
3910 		return 0;
3911 	}
3912 
3913 	err = ipc_has_perm(&shp->shm_perm, perms);
3914 	return err;
3915 }
3916 
3917 static int selinux_shm_shmat(struct shmid_kernel *shp,
3918 			     char __user *shmaddr, int shmflg)
3919 {
3920 	u32 perms;
3921 	int rc;
3922 
3923 	rc = secondary_ops->shm_shmat(shp, shmaddr, shmflg);
3924 	if (rc)
3925 		return rc;
3926 
3927 	if (shmflg & SHM_RDONLY)
3928 		perms = SHM__READ;
3929 	else
3930 		perms = SHM__READ | SHM__WRITE;
3931 
3932 	return ipc_has_perm(&shp->shm_perm, perms);
3933 }
3934 
3935 /* Semaphore security operations */
3936 static int selinux_sem_alloc_security(struct sem_array *sma)
3937 {
3938 	struct task_security_struct *tsec;
3939 	struct ipc_security_struct *isec;
3940 	struct avc_audit_data ad;
3941 	int rc;
3942 
3943 	rc = ipc_alloc_security(current, &sma->sem_perm, SECCLASS_SEM);
3944 	if (rc)
3945 		return rc;
3946 
3947 	tsec = current->security;
3948 	isec = sma->sem_perm.security;
3949 
3950 	AVC_AUDIT_DATA_INIT(&ad, IPC);
3951  	ad.u.ipc_id = sma->sem_perm.key;
3952 
3953 	rc = avc_has_perm(tsec->sid, isec->sid, SECCLASS_SEM,
3954 			  SEM__CREATE, &ad);
3955 	if (rc) {
3956 		ipc_free_security(&sma->sem_perm);
3957 		return rc;
3958 	}
3959 	return 0;
3960 }
3961 
3962 static void selinux_sem_free_security(struct sem_array *sma)
3963 {
3964 	ipc_free_security(&sma->sem_perm);
3965 }
3966 
3967 static int selinux_sem_associate(struct sem_array *sma, int semflg)
3968 {
3969 	struct task_security_struct *tsec;
3970 	struct ipc_security_struct *isec;
3971 	struct avc_audit_data ad;
3972 
3973 	tsec = current->security;
3974 	isec = sma->sem_perm.security;
3975 
3976 	AVC_AUDIT_DATA_INIT(&ad, IPC);
3977 	ad.u.ipc_id = sma->sem_perm.key;
3978 
3979 	return avc_has_perm(tsec->sid, isec->sid, SECCLASS_SEM,
3980 			    SEM__ASSOCIATE, &ad);
3981 }
3982 
3983 /* Note, at this point, sma is locked down */
3984 static int selinux_sem_semctl(struct sem_array *sma, int cmd)
3985 {
3986 	int err;
3987 	u32 perms;
3988 
3989 	switch(cmd) {
3990 	case IPC_INFO:
3991 	case SEM_INFO:
3992 		/* No specific object, just general system-wide information. */
3993 		return task_has_system(current, SYSTEM__IPC_INFO);
3994 	case GETPID:
3995 	case GETNCNT:
3996 	case GETZCNT:
3997 		perms = SEM__GETATTR;
3998 		break;
3999 	case GETVAL:
4000 	case GETALL:
4001 		perms = SEM__READ;
4002 		break;
4003 	case SETVAL:
4004 	case SETALL:
4005 		perms = SEM__WRITE;
4006 		break;
4007 	case IPC_RMID:
4008 		perms = SEM__DESTROY;
4009 		break;
4010 	case IPC_SET:
4011 		perms = SEM__SETATTR;
4012 		break;
4013 	case IPC_STAT:
4014 	case SEM_STAT:
4015 		perms = SEM__GETATTR | SEM__ASSOCIATE;
4016 		break;
4017 	default:
4018 		return 0;
4019 	}
4020 
4021 	err = ipc_has_perm(&sma->sem_perm, perms);
4022 	return err;
4023 }
4024 
4025 static int selinux_sem_semop(struct sem_array *sma,
4026 			     struct sembuf *sops, unsigned nsops, int alter)
4027 {
4028 	u32 perms;
4029 
4030 	if (alter)
4031 		perms = SEM__READ | SEM__WRITE;
4032 	else
4033 		perms = SEM__READ;
4034 
4035 	return ipc_has_perm(&sma->sem_perm, perms);
4036 }
4037 
4038 static int selinux_ipc_permission(struct kern_ipc_perm *ipcp, short flag)
4039 {
4040 	u32 av = 0;
4041 
4042 	av = 0;
4043 	if (flag & S_IRUGO)
4044 		av |= IPC__UNIX_READ;
4045 	if (flag & S_IWUGO)
4046 		av |= IPC__UNIX_WRITE;
4047 
4048 	if (av == 0)
4049 		return 0;
4050 
4051 	return ipc_has_perm(ipcp, av);
4052 }
4053 
4054 /* module stacking operations */
4055 static int selinux_register_security (const char *name, struct security_operations *ops)
4056 {
4057 	if (secondary_ops != original_ops) {
4058 		printk(KERN_INFO "%s:  There is already a secondary security "
4059 		       "module registered.\n", __FUNCTION__);
4060 		return -EINVAL;
4061  	}
4062 
4063 	secondary_ops = ops;
4064 
4065 	printk(KERN_INFO "%s:  Registering secondary module %s\n",
4066 	       __FUNCTION__,
4067 	       name);
4068 
4069 	return 0;
4070 }
4071 
4072 static int selinux_unregister_security (const char *name, struct security_operations *ops)
4073 {
4074 	if (ops != secondary_ops) {
4075 		printk (KERN_INFO "%s:  trying to unregister a security module "
4076 		        "that is not registered.\n", __FUNCTION__);
4077 		return -EINVAL;
4078 	}
4079 
4080 	secondary_ops = original_ops;
4081 
4082 	return 0;
4083 }
4084 
4085 static void selinux_d_instantiate (struct dentry *dentry, struct inode *inode)
4086 {
4087 	if (inode)
4088 		inode_doinit_with_dentry(inode, dentry);
4089 }
4090 
4091 static int selinux_getprocattr(struct task_struct *p,
4092 			       char *name, void *value, size_t size)
4093 {
4094 	struct task_security_struct *tsec;
4095 	u32 sid, len;
4096 	char *context;
4097 	int error;
4098 
4099 	if (current != p) {
4100 		error = task_has_perm(current, p, PROCESS__GETATTR);
4101 		if (error)
4102 			return error;
4103 	}
4104 
4105 	if (!size)
4106 		return -ERANGE;
4107 
4108 	tsec = p->security;
4109 
4110 	if (!strcmp(name, "current"))
4111 		sid = tsec->sid;
4112 	else if (!strcmp(name, "prev"))
4113 		sid = tsec->osid;
4114 	else if (!strcmp(name, "exec"))
4115 		sid = tsec->exec_sid;
4116 	else if (!strcmp(name, "fscreate"))
4117 		sid = tsec->create_sid;
4118 	else
4119 		return -EINVAL;
4120 
4121 	if (!sid)
4122 		return 0;
4123 
4124 	error = security_sid_to_context(sid, &context, &len);
4125 	if (error)
4126 		return error;
4127 	if (len > size) {
4128 		kfree(context);
4129 		return -ERANGE;
4130 	}
4131 	memcpy(value, context, len);
4132 	kfree(context);
4133 	return len;
4134 }
4135 
4136 static int selinux_setprocattr(struct task_struct *p,
4137 			       char *name, void *value, size_t size)
4138 {
4139 	struct task_security_struct *tsec;
4140 	u32 sid = 0;
4141 	int error;
4142 	char *str = value;
4143 
4144 	if (current != p) {
4145 		/* SELinux only allows a process to change its own
4146 		   security attributes. */
4147 		return -EACCES;
4148 	}
4149 
4150 	/*
4151 	 * Basic control over ability to set these attributes at all.
4152 	 * current == p, but we'll pass them separately in case the
4153 	 * above restriction is ever removed.
4154 	 */
4155 	if (!strcmp(name, "exec"))
4156 		error = task_has_perm(current, p, PROCESS__SETEXEC);
4157 	else if (!strcmp(name, "fscreate"))
4158 		error = task_has_perm(current, p, PROCESS__SETFSCREATE);
4159 	else if (!strcmp(name, "current"))
4160 		error = task_has_perm(current, p, PROCESS__SETCURRENT);
4161 	else
4162 		error = -EINVAL;
4163 	if (error)
4164 		return error;
4165 
4166 	/* Obtain a SID for the context, if one was specified. */
4167 	if (size && str[1] && str[1] != '\n') {
4168 		if (str[size-1] == '\n') {
4169 			str[size-1] = 0;
4170 			size--;
4171 		}
4172 		error = security_context_to_sid(value, size, &sid);
4173 		if (error)
4174 			return error;
4175 	}
4176 
4177 	/* Permission checking based on the specified context is
4178 	   performed during the actual operation (execve,
4179 	   open/mkdir/...), when we know the full context of the
4180 	   operation.  See selinux_bprm_set_security for the execve
4181 	   checks and may_create for the file creation checks. The
4182 	   operation will then fail if the context is not permitted. */
4183 	tsec = p->security;
4184 	if (!strcmp(name, "exec"))
4185 		tsec->exec_sid = sid;
4186 	else if (!strcmp(name, "fscreate"))
4187 		tsec->create_sid = sid;
4188 	else if (!strcmp(name, "current")) {
4189 		struct av_decision avd;
4190 
4191 		if (sid == 0)
4192 			return -EINVAL;
4193 
4194 		/* Only allow single threaded processes to change context */
4195 		if (atomic_read(&p->mm->mm_users) != 1) {
4196 			struct task_struct *g, *t;
4197 			struct mm_struct *mm = p->mm;
4198 			read_lock(&tasklist_lock);
4199 			do_each_thread(g, t)
4200 				if (t->mm == mm && t != p) {
4201 					read_unlock(&tasklist_lock);
4202 					return -EPERM;
4203 				}
4204 			while_each_thread(g, t);
4205 			read_unlock(&tasklist_lock);
4206                 }
4207 
4208 		/* Check permissions for the transition. */
4209 		error = avc_has_perm(tsec->sid, sid, SECCLASS_PROCESS,
4210 		                     PROCESS__DYNTRANSITION, NULL);
4211 		if (error)
4212 			return error;
4213 
4214 		/* Check for ptracing, and update the task SID if ok.
4215 		   Otherwise, leave SID unchanged and fail. */
4216 		task_lock(p);
4217 		if (p->ptrace & PT_PTRACED) {
4218 			error = avc_has_perm_noaudit(tsec->ptrace_sid, sid,
4219 						     SECCLASS_PROCESS,
4220 						     PROCESS__PTRACE, &avd);
4221 			if (!error)
4222 				tsec->sid = sid;
4223 			task_unlock(p);
4224 			avc_audit(tsec->ptrace_sid, sid, SECCLASS_PROCESS,
4225 				  PROCESS__PTRACE, &avd, error, NULL);
4226 			if (error)
4227 				return error;
4228 		} else {
4229 			tsec->sid = sid;
4230 			task_unlock(p);
4231 		}
4232 	}
4233 	else
4234 		return -EINVAL;
4235 
4236 	return size;
4237 }
4238 
4239 static struct security_operations selinux_ops = {
4240 	.ptrace =			selinux_ptrace,
4241 	.capget =			selinux_capget,
4242 	.capset_check =			selinux_capset_check,
4243 	.capset_set =			selinux_capset_set,
4244 	.sysctl =			selinux_sysctl,
4245 	.capable =			selinux_capable,
4246 	.quotactl =			selinux_quotactl,
4247 	.quota_on =			selinux_quota_on,
4248 	.syslog =			selinux_syslog,
4249 	.vm_enough_memory =		selinux_vm_enough_memory,
4250 
4251 	.netlink_send =			selinux_netlink_send,
4252         .netlink_recv =			selinux_netlink_recv,
4253 
4254 	.bprm_alloc_security =		selinux_bprm_alloc_security,
4255 	.bprm_free_security =		selinux_bprm_free_security,
4256 	.bprm_apply_creds =		selinux_bprm_apply_creds,
4257 	.bprm_post_apply_creds =	selinux_bprm_post_apply_creds,
4258 	.bprm_set_security =		selinux_bprm_set_security,
4259 	.bprm_check_security =		selinux_bprm_check_security,
4260 	.bprm_secureexec =		selinux_bprm_secureexec,
4261 
4262 	.sb_alloc_security =		selinux_sb_alloc_security,
4263 	.sb_free_security =		selinux_sb_free_security,
4264 	.sb_copy_data =			selinux_sb_copy_data,
4265 	.sb_kern_mount =	        selinux_sb_kern_mount,
4266 	.sb_statfs =			selinux_sb_statfs,
4267 	.sb_mount =			selinux_mount,
4268 	.sb_umount =			selinux_umount,
4269 
4270 	.inode_alloc_security =		selinux_inode_alloc_security,
4271 	.inode_free_security =		selinux_inode_free_security,
4272 	.inode_init_security =		selinux_inode_init_security,
4273 	.inode_create =			selinux_inode_create,
4274 	.inode_link =			selinux_inode_link,
4275 	.inode_unlink =			selinux_inode_unlink,
4276 	.inode_symlink =		selinux_inode_symlink,
4277 	.inode_mkdir =			selinux_inode_mkdir,
4278 	.inode_rmdir =			selinux_inode_rmdir,
4279 	.inode_mknod =			selinux_inode_mknod,
4280 	.inode_rename =			selinux_inode_rename,
4281 	.inode_readlink =		selinux_inode_readlink,
4282 	.inode_follow_link =		selinux_inode_follow_link,
4283 	.inode_permission =		selinux_inode_permission,
4284 	.inode_setattr =		selinux_inode_setattr,
4285 	.inode_getattr =		selinux_inode_getattr,
4286 	.inode_setxattr =		selinux_inode_setxattr,
4287 	.inode_post_setxattr =		selinux_inode_post_setxattr,
4288 	.inode_getxattr =		selinux_inode_getxattr,
4289 	.inode_listxattr =		selinux_inode_listxattr,
4290 	.inode_removexattr =		selinux_inode_removexattr,
4291 	.inode_getsecurity =            selinux_inode_getsecurity,
4292 	.inode_setsecurity =            selinux_inode_setsecurity,
4293 	.inode_listsecurity =           selinux_inode_listsecurity,
4294 
4295 	.file_permission =		selinux_file_permission,
4296 	.file_alloc_security =		selinux_file_alloc_security,
4297 	.file_free_security =		selinux_file_free_security,
4298 	.file_ioctl =			selinux_file_ioctl,
4299 	.file_mmap =			selinux_file_mmap,
4300 	.file_mprotect =		selinux_file_mprotect,
4301 	.file_lock =			selinux_file_lock,
4302 	.file_fcntl =			selinux_file_fcntl,
4303 	.file_set_fowner =		selinux_file_set_fowner,
4304 	.file_send_sigiotask =		selinux_file_send_sigiotask,
4305 	.file_receive =			selinux_file_receive,
4306 
4307 	.task_create =			selinux_task_create,
4308 	.task_alloc_security =		selinux_task_alloc_security,
4309 	.task_free_security =		selinux_task_free_security,
4310 	.task_setuid =			selinux_task_setuid,
4311 	.task_post_setuid =		selinux_task_post_setuid,
4312 	.task_setgid =			selinux_task_setgid,
4313 	.task_setpgid =			selinux_task_setpgid,
4314 	.task_getpgid =			selinux_task_getpgid,
4315 	.task_getsid =		        selinux_task_getsid,
4316 	.task_setgroups =		selinux_task_setgroups,
4317 	.task_setnice =			selinux_task_setnice,
4318 	.task_setrlimit =		selinux_task_setrlimit,
4319 	.task_setscheduler =		selinux_task_setscheduler,
4320 	.task_getscheduler =		selinux_task_getscheduler,
4321 	.task_kill =			selinux_task_kill,
4322 	.task_wait =			selinux_task_wait,
4323 	.task_prctl =			selinux_task_prctl,
4324 	.task_reparent_to_init =	selinux_task_reparent_to_init,
4325 	.task_to_inode =                selinux_task_to_inode,
4326 
4327 	.ipc_permission =		selinux_ipc_permission,
4328 
4329 	.msg_msg_alloc_security =	selinux_msg_msg_alloc_security,
4330 	.msg_msg_free_security =	selinux_msg_msg_free_security,
4331 
4332 	.msg_queue_alloc_security =	selinux_msg_queue_alloc_security,
4333 	.msg_queue_free_security =	selinux_msg_queue_free_security,
4334 	.msg_queue_associate =		selinux_msg_queue_associate,
4335 	.msg_queue_msgctl =		selinux_msg_queue_msgctl,
4336 	.msg_queue_msgsnd =		selinux_msg_queue_msgsnd,
4337 	.msg_queue_msgrcv =		selinux_msg_queue_msgrcv,
4338 
4339 	.shm_alloc_security =		selinux_shm_alloc_security,
4340 	.shm_free_security =		selinux_shm_free_security,
4341 	.shm_associate =		selinux_shm_associate,
4342 	.shm_shmctl =			selinux_shm_shmctl,
4343 	.shm_shmat =			selinux_shm_shmat,
4344 
4345 	.sem_alloc_security = 		selinux_sem_alloc_security,
4346 	.sem_free_security =  		selinux_sem_free_security,
4347 	.sem_associate =		selinux_sem_associate,
4348 	.sem_semctl =			selinux_sem_semctl,
4349 	.sem_semop =			selinux_sem_semop,
4350 
4351 	.register_security =		selinux_register_security,
4352 	.unregister_security =		selinux_unregister_security,
4353 
4354 	.d_instantiate =                selinux_d_instantiate,
4355 
4356 	.getprocattr =                  selinux_getprocattr,
4357 	.setprocattr =                  selinux_setprocattr,
4358 
4359 #ifdef CONFIG_SECURITY_NETWORK
4360         .unix_stream_connect =		selinux_socket_unix_stream_connect,
4361 	.unix_may_send =		selinux_socket_unix_may_send,
4362 
4363 	.socket_create =		selinux_socket_create,
4364 	.socket_post_create =		selinux_socket_post_create,
4365 	.socket_bind =			selinux_socket_bind,
4366 	.socket_connect =		selinux_socket_connect,
4367 	.socket_listen =		selinux_socket_listen,
4368 	.socket_accept =		selinux_socket_accept,
4369 	.socket_sendmsg =		selinux_socket_sendmsg,
4370 	.socket_recvmsg =		selinux_socket_recvmsg,
4371 	.socket_getsockname =		selinux_socket_getsockname,
4372 	.socket_getpeername =		selinux_socket_getpeername,
4373 	.socket_getsockopt =		selinux_socket_getsockopt,
4374 	.socket_setsockopt =		selinux_socket_setsockopt,
4375 	.socket_shutdown =		selinux_socket_shutdown,
4376 	.socket_sock_rcv_skb =		selinux_socket_sock_rcv_skb,
4377 	.socket_getpeersec =		selinux_socket_getpeersec,
4378 	.sk_alloc_security =		selinux_sk_alloc_security,
4379 	.sk_free_security =		selinux_sk_free_security,
4380 #endif
4381 };
4382 
4383 static __init int selinux_init(void)
4384 {
4385 	struct task_security_struct *tsec;
4386 
4387 	if (!selinux_enabled) {
4388 		printk(KERN_INFO "SELinux:  Disabled at boot.\n");
4389 		return 0;
4390 	}
4391 
4392 	printk(KERN_INFO "SELinux:  Initializing.\n");
4393 
4394 	/* Set the security state for the initial task. */
4395 	if (task_alloc_security(current))
4396 		panic("SELinux:  Failed to initialize initial task.\n");
4397 	tsec = current->security;
4398 	tsec->osid = tsec->sid = SECINITSID_KERNEL;
4399 
4400 	avc_init();
4401 
4402 	original_ops = secondary_ops = security_ops;
4403 	if (!secondary_ops)
4404 		panic ("SELinux: No initial security operations\n");
4405 	if (register_security (&selinux_ops))
4406 		panic("SELinux: Unable to register with kernel.\n");
4407 
4408 	if (selinux_enforcing) {
4409 		printk(KERN_INFO "SELinux:  Starting in enforcing mode\n");
4410 	} else {
4411 		printk(KERN_INFO "SELinux:  Starting in permissive mode\n");
4412 	}
4413 	return 0;
4414 }
4415 
4416 void selinux_complete_init(void)
4417 {
4418 	printk(KERN_INFO "SELinux:  Completing initialization.\n");
4419 
4420 	/* Set up any superblocks initialized prior to the policy load. */
4421 	printk(KERN_INFO "SELinux:  Setting up existing superblocks.\n");
4422 	spin_lock(&sb_security_lock);
4423 next_sb:
4424 	if (!list_empty(&superblock_security_head)) {
4425 		struct superblock_security_struct *sbsec =
4426 				list_entry(superblock_security_head.next,
4427 				           struct superblock_security_struct,
4428 				           list);
4429 		struct super_block *sb = sbsec->sb;
4430 		spin_lock(&sb_lock);
4431 		sb->s_count++;
4432 		spin_unlock(&sb_lock);
4433 		spin_unlock(&sb_security_lock);
4434 		down_read(&sb->s_umount);
4435 		if (sb->s_root)
4436 			superblock_doinit(sb, NULL);
4437 		drop_super(sb);
4438 		spin_lock(&sb_security_lock);
4439 		list_del_init(&sbsec->list);
4440 		goto next_sb;
4441 	}
4442 	spin_unlock(&sb_security_lock);
4443 }
4444 
4445 /* SELinux requires early initialization in order to label
4446    all processes and objects when they are created. */
4447 security_initcall(selinux_init);
4448 
4449 #if defined(CONFIG_SECURITY_NETWORK) && defined(CONFIG_NETFILTER)
4450 
4451 static struct nf_hook_ops selinux_ipv4_op = {
4452 	.hook =		selinux_ipv4_postroute_last,
4453 	.owner =	THIS_MODULE,
4454 	.pf =		PF_INET,
4455 	.hooknum =	NF_IP_POST_ROUTING,
4456 	.priority =	NF_IP_PRI_SELINUX_LAST,
4457 };
4458 
4459 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
4460 
4461 static struct nf_hook_ops selinux_ipv6_op = {
4462 	.hook =		selinux_ipv6_postroute_last,
4463 	.owner =	THIS_MODULE,
4464 	.pf =		PF_INET6,
4465 	.hooknum =	NF_IP6_POST_ROUTING,
4466 	.priority =	NF_IP6_PRI_SELINUX_LAST,
4467 };
4468 
4469 #endif	/* IPV6 */
4470 
4471 static int __init selinux_nf_ip_init(void)
4472 {
4473 	int err = 0;
4474 
4475 	if (!selinux_enabled)
4476 		goto out;
4477 
4478 	printk(KERN_INFO "SELinux:  Registering netfilter hooks\n");
4479 
4480 	err = nf_register_hook(&selinux_ipv4_op);
4481 	if (err)
4482 		panic("SELinux: nf_register_hook for IPv4: error %d\n", err);
4483 
4484 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
4485 
4486 	err = nf_register_hook(&selinux_ipv6_op);
4487 	if (err)
4488 		panic("SELinux: nf_register_hook for IPv6: error %d\n", err);
4489 
4490 #endif	/* IPV6 */
4491 out:
4492 	return err;
4493 }
4494 
4495 __initcall(selinux_nf_ip_init);
4496 
4497 #ifdef CONFIG_SECURITY_SELINUX_DISABLE
4498 static void selinux_nf_ip_exit(void)
4499 {
4500 	printk(KERN_INFO "SELinux:  Unregistering netfilter hooks\n");
4501 
4502 	nf_unregister_hook(&selinux_ipv4_op);
4503 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
4504 	nf_unregister_hook(&selinux_ipv6_op);
4505 #endif	/* IPV6 */
4506 }
4507 #endif
4508 
4509 #else /* CONFIG_SECURITY_NETWORK && CONFIG_NETFILTER */
4510 
4511 #ifdef CONFIG_SECURITY_SELINUX_DISABLE
4512 #define selinux_nf_ip_exit()
4513 #endif
4514 
4515 #endif /* CONFIG_SECURITY_NETWORK && CONFIG_NETFILTER */
4516 
4517 #ifdef CONFIG_SECURITY_SELINUX_DISABLE
4518 int selinux_disable(void)
4519 {
4520 	extern void exit_sel_fs(void);
4521 	static int selinux_disabled = 0;
4522 
4523 	if (ss_initialized) {
4524 		/* Not permitted after initial policy load. */
4525 		return -EINVAL;
4526 	}
4527 
4528 	if (selinux_disabled) {
4529 		/* Only do this once. */
4530 		return -EINVAL;
4531 	}
4532 
4533 	printk(KERN_INFO "SELinux:  Disabled at runtime.\n");
4534 
4535 	selinux_disabled = 1;
4536 
4537 	/* Reset security_ops to the secondary module, dummy or capability. */
4538 	security_ops = secondary_ops;
4539 
4540 	/* Unregister netfilter hooks. */
4541 	selinux_nf_ip_exit();
4542 
4543 	/* Unregister selinuxfs. */
4544 	exit_sel_fs();
4545 
4546 	return 0;
4547 }
4548 #endif
4549 
4550 
4551