xref: /linux/security/selinux/hooks.c (revision 87c2ce3b9305b9b723faeedf6e32ef703ec9b33a)
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 #include "xfrm.h"
77 
78 #define XATTR_SELINUX_SUFFIX "selinux"
79 #define XATTR_NAME_SELINUX XATTR_SECURITY_PREFIX XATTR_SELINUX_SUFFIX
80 
81 extern unsigned int policydb_loaded_version;
82 extern int selinux_nlmsg_lookup(u16 sclass, u16 nlmsg_type, u32 *perm);
83 
84 #ifdef CONFIG_SECURITY_SELINUX_DEVELOP
85 int selinux_enforcing = 0;
86 
87 static int __init enforcing_setup(char *str)
88 {
89 	selinux_enforcing = simple_strtol(str,NULL,0);
90 	return 1;
91 }
92 __setup("enforcing=", enforcing_setup);
93 #endif
94 
95 #ifdef CONFIG_SECURITY_SELINUX_BOOTPARAM
96 int selinux_enabled = CONFIG_SECURITY_SELINUX_BOOTPARAM_VALUE;
97 
98 static int __init selinux_enabled_setup(char *str)
99 {
100 	selinux_enabled = simple_strtol(str, NULL, 0);
101 	return 1;
102 }
103 __setup("selinux=", selinux_enabled_setup);
104 #endif
105 
106 /* Original (dummy) security module. */
107 static struct security_operations *original_ops = NULL;
108 
109 /* Minimal support for a secondary security module,
110    just to allow the use of the dummy or capability modules.
111    The owlsm module can alternatively be used as a secondary
112    module as long as CONFIG_OWLSM_FD is not enabled. */
113 static struct security_operations *secondary_ops = NULL;
114 
115 /* Lists of inode and superblock security structures initialized
116    before the policy was loaded. */
117 static LIST_HEAD(superblock_security_head);
118 static DEFINE_SPINLOCK(sb_security_lock);
119 
120 /* Allocate and free functions for each kind of security blob. */
121 
122 static int task_alloc_security(struct task_struct *task)
123 {
124 	struct task_security_struct *tsec;
125 
126 	tsec = kzalloc(sizeof(struct task_security_struct), GFP_KERNEL);
127 	if (!tsec)
128 		return -ENOMEM;
129 
130 	tsec->magic = SELINUX_MAGIC;
131 	tsec->task = task;
132 	tsec->osid = tsec->sid = tsec->ptrace_sid = SECINITSID_UNLABELED;
133 	task->security = tsec;
134 
135 	return 0;
136 }
137 
138 static void task_free_security(struct task_struct *task)
139 {
140 	struct task_security_struct *tsec = task->security;
141 
142 	if (!tsec || tsec->magic != SELINUX_MAGIC)
143 		return;
144 
145 	task->security = NULL;
146 	kfree(tsec);
147 }
148 
149 static int inode_alloc_security(struct inode *inode)
150 {
151 	struct task_security_struct *tsec = current->security;
152 	struct inode_security_struct *isec;
153 
154 	isec = kzalloc(sizeof(struct inode_security_struct), GFP_KERNEL);
155 	if (!isec)
156 		return -ENOMEM;
157 
158 	init_MUTEX(&isec->sem);
159 	INIT_LIST_HEAD(&isec->list);
160 	isec->magic = SELINUX_MAGIC;
161 	isec->inode = inode;
162 	isec->sid = SECINITSID_UNLABELED;
163 	isec->sclass = SECCLASS_FILE;
164 	if (tsec && tsec->magic == SELINUX_MAGIC)
165 		isec->task_sid = tsec->sid;
166 	else
167 		isec->task_sid = SECINITSID_UNLABELED;
168 	inode->i_security = isec;
169 
170 	return 0;
171 }
172 
173 static void inode_free_security(struct inode *inode)
174 {
175 	struct inode_security_struct *isec = inode->i_security;
176 	struct superblock_security_struct *sbsec = inode->i_sb->s_security;
177 
178 	if (!isec || isec->magic != SELINUX_MAGIC)
179 		return;
180 
181 	spin_lock(&sbsec->isec_lock);
182 	if (!list_empty(&isec->list))
183 		list_del_init(&isec->list);
184 	spin_unlock(&sbsec->isec_lock);
185 
186 	inode->i_security = NULL;
187 	kfree(isec);
188 }
189 
190 static int file_alloc_security(struct file *file)
191 {
192 	struct task_security_struct *tsec = current->security;
193 	struct file_security_struct *fsec;
194 
195 	fsec = kzalloc(sizeof(struct file_security_struct), GFP_ATOMIC);
196 	if (!fsec)
197 		return -ENOMEM;
198 
199 	fsec->magic = SELINUX_MAGIC;
200 	fsec->file = file;
201 	if (tsec && tsec->magic == SELINUX_MAGIC) {
202 		fsec->sid = tsec->sid;
203 		fsec->fown_sid = tsec->sid;
204 	} else {
205 		fsec->sid = SECINITSID_UNLABELED;
206 		fsec->fown_sid = SECINITSID_UNLABELED;
207 	}
208 	file->f_security = fsec;
209 
210 	return 0;
211 }
212 
213 static void file_free_security(struct file *file)
214 {
215 	struct file_security_struct *fsec = file->f_security;
216 
217 	if (!fsec || fsec->magic != SELINUX_MAGIC)
218 		return;
219 
220 	file->f_security = NULL;
221 	kfree(fsec);
222 }
223 
224 static int superblock_alloc_security(struct super_block *sb)
225 {
226 	struct superblock_security_struct *sbsec;
227 
228 	sbsec = kzalloc(sizeof(struct superblock_security_struct), GFP_KERNEL);
229 	if (!sbsec)
230 		return -ENOMEM;
231 
232 	init_MUTEX(&sbsec->sem);
233 	INIT_LIST_HEAD(&sbsec->list);
234 	INIT_LIST_HEAD(&sbsec->isec_head);
235 	spin_lock_init(&sbsec->isec_lock);
236 	sbsec->magic = SELINUX_MAGIC;
237 	sbsec->sb = sb;
238 	sbsec->sid = SECINITSID_UNLABELED;
239 	sbsec->def_sid = SECINITSID_FILE;
240 	sb->s_security = sbsec;
241 
242 	return 0;
243 }
244 
245 static void superblock_free_security(struct super_block *sb)
246 {
247 	struct superblock_security_struct *sbsec = sb->s_security;
248 
249 	if (!sbsec || sbsec->magic != SELINUX_MAGIC)
250 		return;
251 
252 	spin_lock(&sb_security_lock);
253 	if (!list_empty(&sbsec->list))
254 		list_del_init(&sbsec->list);
255 	spin_unlock(&sb_security_lock);
256 
257 	sb->s_security = NULL;
258 	kfree(sbsec);
259 }
260 
261 #ifdef CONFIG_SECURITY_NETWORK
262 static int sk_alloc_security(struct sock *sk, int family, gfp_t priority)
263 {
264 	struct sk_security_struct *ssec;
265 
266 	if (family != PF_UNIX)
267 		return 0;
268 
269 	ssec = kzalloc(sizeof(*ssec), priority);
270 	if (!ssec)
271 		return -ENOMEM;
272 
273 	ssec->magic = SELINUX_MAGIC;
274 	ssec->sk = sk;
275 	ssec->peer_sid = SECINITSID_UNLABELED;
276 	sk->sk_security = ssec;
277 
278 	return 0;
279 }
280 
281 static void sk_free_security(struct sock *sk)
282 {
283 	struct sk_security_struct *ssec = sk->sk_security;
284 
285 	if (sk->sk_family != PF_UNIX || ssec->magic != SELINUX_MAGIC)
286 		return;
287 
288 	sk->sk_security = NULL;
289 	kfree(ssec);
290 }
291 #endif	/* CONFIG_SECURITY_NETWORK */
292 
293 /* The security server must be initialized before
294    any labeling or access decisions can be provided. */
295 extern int ss_initialized;
296 
297 /* The file system's label must be initialized prior to use. */
298 
299 static char *labeling_behaviors[6] = {
300 	"uses xattr",
301 	"uses transition SIDs",
302 	"uses task SIDs",
303 	"uses genfs_contexts",
304 	"not configured for labeling",
305 	"uses mountpoint labeling",
306 };
307 
308 static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dentry);
309 
310 static inline int inode_doinit(struct inode *inode)
311 {
312 	return inode_doinit_with_dentry(inode, NULL);
313 }
314 
315 enum {
316 	Opt_context = 1,
317 	Opt_fscontext = 2,
318 	Opt_defcontext = 4,
319 };
320 
321 static match_table_t tokens = {
322 	{Opt_context, "context=%s"},
323 	{Opt_fscontext, "fscontext=%s"},
324 	{Opt_defcontext, "defcontext=%s"},
325 };
326 
327 #define SEL_MOUNT_FAIL_MSG "SELinux:  duplicate or incompatible mount options\n"
328 
329 static int try_context_mount(struct super_block *sb, void *data)
330 {
331 	char *context = NULL, *defcontext = NULL;
332 	const char *name;
333 	u32 sid;
334 	int alloc = 0, rc = 0, seen = 0;
335 	struct task_security_struct *tsec = current->security;
336 	struct superblock_security_struct *sbsec = sb->s_security;
337 
338 	if (!data)
339 		goto out;
340 
341 	name = sb->s_type->name;
342 
343 	if (sb->s_type->fs_flags & FS_BINARY_MOUNTDATA) {
344 
345 		/* NFS we understand. */
346 		if (!strcmp(name, "nfs")) {
347 			struct nfs_mount_data *d = data;
348 
349 			if (d->version <  NFS_MOUNT_VERSION)
350 				goto out;
351 
352 			if (d->context[0]) {
353 				context = d->context;
354 				seen |= Opt_context;
355 			}
356 		} else
357 			goto out;
358 
359 	} else {
360 		/* Standard string-based options. */
361 		char *p, *options = data;
362 
363 		while ((p = strsep(&options, ",")) != NULL) {
364 			int token;
365 			substring_t args[MAX_OPT_ARGS];
366 
367 			if (!*p)
368 				continue;
369 
370 			token = match_token(p, tokens, args);
371 
372 			switch (token) {
373 			case Opt_context:
374 				if (seen) {
375 					rc = -EINVAL;
376 					printk(KERN_WARNING SEL_MOUNT_FAIL_MSG);
377 					goto out_free;
378 				}
379 				context = match_strdup(&args[0]);
380 				if (!context) {
381 					rc = -ENOMEM;
382 					goto out_free;
383 				}
384 				if (!alloc)
385 					alloc = 1;
386 				seen |= Opt_context;
387 				break;
388 
389 			case Opt_fscontext:
390 				if (seen & (Opt_context|Opt_fscontext)) {
391 					rc = -EINVAL;
392 					printk(KERN_WARNING SEL_MOUNT_FAIL_MSG);
393 					goto out_free;
394 				}
395 				context = match_strdup(&args[0]);
396 				if (!context) {
397 					rc = -ENOMEM;
398 					goto out_free;
399 				}
400 				if (!alloc)
401 					alloc = 1;
402 				seen |= Opt_fscontext;
403 				break;
404 
405 			case Opt_defcontext:
406 				if (sbsec->behavior != SECURITY_FS_USE_XATTR) {
407 					rc = -EINVAL;
408 					printk(KERN_WARNING "SELinux:  "
409 					       "defcontext option is invalid "
410 					       "for this filesystem type\n");
411 					goto out_free;
412 				}
413 				if (seen & (Opt_context|Opt_defcontext)) {
414 					rc = -EINVAL;
415 					printk(KERN_WARNING SEL_MOUNT_FAIL_MSG);
416 					goto out_free;
417 				}
418 				defcontext = match_strdup(&args[0]);
419 				if (!defcontext) {
420 					rc = -ENOMEM;
421 					goto out_free;
422 				}
423 				if (!alloc)
424 					alloc = 1;
425 				seen |= Opt_defcontext;
426 				break;
427 
428 			default:
429 				rc = -EINVAL;
430 				printk(KERN_WARNING "SELinux:  unknown mount "
431 				       "option\n");
432 				goto out_free;
433 
434 			}
435 		}
436 	}
437 
438 	if (!seen)
439 		goto out;
440 
441 	if (context) {
442 		rc = security_context_to_sid(context, strlen(context), &sid);
443 		if (rc) {
444 			printk(KERN_WARNING "SELinux: security_context_to_sid"
445 			       "(%s) failed for (dev %s, type %s) errno=%d\n",
446 			       context, sb->s_id, name, rc);
447 			goto out_free;
448 		}
449 
450 		rc = avc_has_perm(tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM,
451 		                  FILESYSTEM__RELABELFROM, NULL);
452 		if (rc)
453 			goto out_free;
454 
455 		rc = avc_has_perm(tsec->sid, sid, SECCLASS_FILESYSTEM,
456 		                  FILESYSTEM__RELABELTO, NULL);
457 		if (rc)
458 			goto out_free;
459 
460 		sbsec->sid = sid;
461 
462 		if (seen & Opt_context)
463 			sbsec->behavior = SECURITY_FS_USE_MNTPOINT;
464 	}
465 
466 	if (defcontext) {
467 		rc = security_context_to_sid(defcontext, strlen(defcontext), &sid);
468 		if (rc) {
469 			printk(KERN_WARNING "SELinux: security_context_to_sid"
470 			       "(%s) failed for (dev %s, type %s) errno=%d\n",
471 			       defcontext, sb->s_id, name, rc);
472 			goto out_free;
473 		}
474 
475 		if (sid == sbsec->def_sid)
476 			goto out_free;
477 
478 		rc = avc_has_perm(tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM,
479 				  FILESYSTEM__RELABELFROM, NULL);
480 		if (rc)
481 			goto out_free;
482 
483 		rc = avc_has_perm(sid, sbsec->sid, SECCLASS_FILESYSTEM,
484 				  FILESYSTEM__ASSOCIATE, NULL);
485 		if (rc)
486 			goto out_free;
487 
488 		sbsec->def_sid = sid;
489 	}
490 
491 out_free:
492 	if (alloc) {
493 		kfree(context);
494 		kfree(defcontext);
495 	}
496 out:
497 	return rc;
498 }
499 
500 static int superblock_doinit(struct super_block *sb, void *data)
501 {
502 	struct superblock_security_struct *sbsec = sb->s_security;
503 	struct dentry *root = sb->s_root;
504 	struct inode *inode = root->d_inode;
505 	int rc = 0;
506 
507 	down(&sbsec->sem);
508 	if (sbsec->initialized)
509 		goto out;
510 
511 	if (!ss_initialized) {
512 		/* Defer initialization until selinux_complete_init,
513 		   after the initial policy is loaded and the security
514 		   server is ready to handle calls. */
515 		spin_lock(&sb_security_lock);
516 		if (list_empty(&sbsec->list))
517 			list_add(&sbsec->list, &superblock_security_head);
518 		spin_unlock(&sb_security_lock);
519 		goto out;
520 	}
521 
522 	/* Determine the labeling behavior to use for this filesystem type. */
523 	rc = security_fs_use(sb->s_type->name, &sbsec->behavior, &sbsec->sid);
524 	if (rc) {
525 		printk(KERN_WARNING "%s:  security_fs_use(%s) returned %d\n",
526 		       __FUNCTION__, sb->s_type->name, rc);
527 		goto out;
528 	}
529 
530 	rc = try_context_mount(sb, data);
531 	if (rc)
532 		goto out;
533 
534 	if (sbsec->behavior == SECURITY_FS_USE_XATTR) {
535 		/* Make sure that the xattr handler exists and that no
536 		   error other than -ENODATA is returned by getxattr on
537 		   the root directory.  -ENODATA is ok, as this may be
538 		   the first boot of the SELinux kernel before we have
539 		   assigned xattr values to the filesystem. */
540 		if (!inode->i_op->getxattr) {
541 			printk(KERN_WARNING "SELinux: (dev %s, type %s) has no "
542 			       "xattr support\n", sb->s_id, sb->s_type->name);
543 			rc = -EOPNOTSUPP;
544 			goto out;
545 		}
546 		rc = inode->i_op->getxattr(root, XATTR_NAME_SELINUX, NULL, 0);
547 		if (rc < 0 && rc != -ENODATA) {
548 			if (rc == -EOPNOTSUPP)
549 				printk(KERN_WARNING "SELinux: (dev %s, type "
550 				       "%s) has no security xattr handler\n",
551 				       sb->s_id, sb->s_type->name);
552 			else
553 				printk(KERN_WARNING "SELinux: (dev %s, type "
554 				       "%s) getxattr errno %d\n", sb->s_id,
555 				       sb->s_type->name, -rc);
556 			goto out;
557 		}
558 	}
559 
560 	if (strcmp(sb->s_type->name, "proc") == 0)
561 		sbsec->proc = 1;
562 
563 	sbsec->initialized = 1;
564 
565 	if (sbsec->behavior > ARRAY_SIZE(labeling_behaviors)) {
566 		printk(KERN_INFO "SELinux: initialized (dev %s, type %s), unknown behavior\n",
567 		       sb->s_id, sb->s_type->name);
568 	}
569 	else {
570 		printk(KERN_INFO "SELinux: initialized (dev %s, type %s), %s\n",
571 		       sb->s_id, sb->s_type->name,
572 		       labeling_behaviors[sbsec->behavior-1]);
573 	}
574 
575 	/* Initialize the root inode. */
576 	rc = inode_doinit_with_dentry(sb->s_root->d_inode, sb->s_root);
577 
578 	/* Initialize any other inodes associated with the superblock, e.g.
579 	   inodes created prior to initial policy load or inodes created
580 	   during get_sb by a pseudo filesystem that directly
581 	   populates itself. */
582 	spin_lock(&sbsec->isec_lock);
583 next_inode:
584 	if (!list_empty(&sbsec->isec_head)) {
585 		struct inode_security_struct *isec =
586 				list_entry(sbsec->isec_head.next,
587 				           struct inode_security_struct, list);
588 		struct inode *inode = isec->inode;
589 		spin_unlock(&sbsec->isec_lock);
590 		inode = igrab(inode);
591 		if (inode) {
592 			if (!IS_PRIVATE (inode))
593 				inode_doinit(inode);
594 			iput(inode);
595 		}
596 		spin_lock(&sbsec->isec_lock);
597 		list_del_init(&isec->list);
598 		goto next_inode;
599 	}
600 	spin_unlock(&sbsec->isec_lock);
601 out:
602 	up(&sbsec->sem);
603 	return rc;
604 }
605 
606 static inline u16 inode_mode_to_security_class(umode_t mode)
607 {
608 	switch (mode & S_IFMT) {
609 	case S_IFSOCK:
610 		return SECCLASS_SOCK_FILE;
611 	case S_IFLNK:
612 		return SECCLASS_LNK_FILE;
613 	case S_IFREG:
614 		return SECCLASS_FILE;
615 	case S_IFBLK:
616 		return SECCLASS_BLK_FILE;
617 	case S_IFDIR:
618 		return SECCLASS_DIR;
619 	case S_IFCHR:
620 		return SECCLASS_CHR_FILE;
621 	case S_IFIFO:
622 		return SECCLASS_FIFO_FILE;
623 
624 	}
625 
626 	return SECCLASS_FILE;
627 }
628 
629 static inline int default_protocol_stream(int protocol)
630 {
631 	return (protocol == IPPROTO_IP || protocol == IPPROTO_TCP);
632 }
633 
634 static inline int default_protocol_dgram(int protocol)
635 {
636 	return (protocol == IPPROTO_IP || protocol == IPPROTO_UDP);
637 }
638 
639 static inline u16 socket_type_to_security_class(int family, int type, int protocol)
640 {
641 	switch (family) {
642 	case PF_UNIX:
643 		switch (type) {
644 		case SOCK_STREAM:
645 		case SOCK_SEQPACKET:
646 			return SECCLASS_UNIX_STREAM_SOCKET;
647 		case SOCK_DGRAM:
648 			return SECCLASS_UNIX_DGRAM_SOCKET;
649 		}
650 		break;
651 	case PF_INET:
652 	case PF_INET6:
653 		switch (type) {
654 		case SOCK_STREAM:
655 			if (default_protocol_stream(protocol))
656 				return SECCLASS_TCP_SOCKET;
657 			else
658 				return SECCLASS_RAWIP_SOCKET;
659 		case SOCK_DGRAM:
660 			if (default_protocol_dgram(protocol))
661 				return SECCLASS_UDP_SOCKET;
662 			else
663 				return SECCLASS_RAWIP_SOCKET;
664 		default:
665 			return SECCLASS_RAWIP_SOCKET;
666 		}
667 		break;
668 	case PF_NETLINK:
669 		switch (protocol) {
670 		case NETLINK_ROUTE:
671 			return SECCLASS_NETLINK_ROUTE_SOCKET;
672 		case NETLINK_FIREWALL:
673 			return SECCLASS_NETLINK_FIREWALL_SOCKET;
674 		case NETLINK_INET_DIAG:
675 			return SECCLASS_NETLINK_TCPDIAG_SOCKET;
676 		case NETLINK_NFLOG:
677 			return SECCLASS_NETLINK_NFLOG_SOCKET;
678 		case NETLINK_XFRM:
679 			return SECCLASS_NETLINK_XFRM_SOCKET;
680 		case NETLINK_SELINUX:
681 			return SECCLASS_NETLINK_SELINUX_SOCKET;
682 		case NETLINK_AUDIT:
683 			return SECCLASS_NETLINK_AUDIT_SOCKET;
684 		case NETLINK_IP6_FW:
685 			return SECCLASS_NETLINK_IP6FW_SOCKET;
686 		case NETLINK_DNRTMSG:
687 			return SECCLASS_NETLINK_DNRT_SOCKET;
688 		case NETLINK_KOBJECT_UEVENT:
689 			return SECCLASS_NETLINK_KOBJECT_UEVENT_SOCKET;
690 		default:
691 			return SECCLASS_NETLINK_SOCKET;
692 		}
693 	case PF_PACKET:
694 		return SECCLASS_PACKET_SOCKET;
695 	case PF_KEY:
696 		return SECCLASS_KEY_SOCKET;
697 	}
698 
699 	return SECCLASS_SOCKET;
700 }
701 
702 #ifdef CONFIG_PROC_FS
703 static int selinux_proc_get_sid(struct proc_dir_entry *de,
704 				u16 tclass,
705 				u32 *sid)
706 {
707 	int buflen, rc;
708 	char *buffer, *path, *end;
709 
710 	buffer = (char*)__get_free_page(GFP_KERNEL);
711 	if (!buffer)
712 		return -ENOMEM;
713 
714 	buflen = PAGE_SIZE;
715 	end = buffer+buflen;
716 	*--end = '\0';
717 	buflen--;
718 	path = end-1;
719 	*path = '/';
720 	while (de && de != de->parent) {
721 		buflen -= de->namelen + 1;
722 		if (buflen < 0)
723 			break;
724 		end -= de->namelen;
725 		memcpy(end, de->name, de->namelen);
726 		*--end = '/';
727 		path = end;
728 		de = de->parent;
729 	}
730 	rc = security_genfs_sid("proc", path, tclass, sid);
731 	free_page((unsigned long)buffer);
732 	return rc;
733 }
734 #else
735 static int selinux_proc_get_sid(struct proc_dir_entry *de,
736 				u16 tclass,
737 				u32 *sid)
738 {
739 	return -EINVAL;
740 }
741 #endif
742 
743 /* The inode's security attributes must be initialized before first use. */
744 static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dentry)
745 {
746 	struct superblock_security_struct *sbsec = NULL;
747 	struct inode_security_struct *isec = inode->i_security;
748 	u32 sid;
749 	struct dentry *dentry;
750 #define INITCONTEXTLEN 255
751 	char *context = NULL;
752 	unsigned len = 0;
753 	int rc = 0;
754 	int hold_sem = 0;
755 
756 	if (isec->initialized)
757 		goto out;
758 
759 	down(&isec->sem);
760 	hold_sem = 1;
761 	if (isec->initialized)
762 		goto out;
763 
764 	sbsec = inode->i_sb->s_security;
765 	if (!sbsec->initialized) {
766 		/* Defer initialization until selinux_complete_init,
767 		   after the initial policy is loaded and the security
768 		   server is ready to handle calls. */
769 		spin_lock(&sbsec->isec_lock);
770 		if (list_empty(&isec->list))
771 			list_add(&isec->list, &sbsec->isec_head);
772 		spin_unlock(&sbsec->isec_lock);
773 		goto out;
774 	}
775 
776 	switch (sbsec->behavior) {
777 	case SECURITY_FS_USE_XATTR:
778 		if (!inode->i_op->getxattr) {
779 			isec->sid = sbsec->def_sid;
780 			break;
781 		}
782 
783 		/* Need a dentry, since the xattr API requires one.
784 		   Life would be simpler if we could just pass the inode. */
785 		if (opt_dentry) {
786 			/* Called from d_instantiate or d_splice_alias. */
787 			dentry = dget(opt_dentry);
788 		} else {
789 			/* Called from selinux_complete_init, try to find a dentry. */
790 			dentry = d_find_alias(inode);
791 		}
792 		if (!dentry) {
793 			printk(KERN_WARNING "%s:  no dentry for dev=%s "
794 			       "ino=%ld\n", __FUNCTION__, inode->i_sb->s_id,
795 			       inode->i_ino);
796 			goto out;
797 		}
798 
799 		len = INITCONTEXTLEN;
800 		context = kmalloc(len, GFP_KERNEL);
801 		if (!context) {
802 			rc = -ENOMEM;
803 			dput(dentry);
804 			goto out;
805 		}
806 		rc = inode->i_op->getxattr(dentry, XATTR_NAME_SELINUX,
807 					   context, len);
808 		if (rc == -ERANGE) {
809 			/* Need a larger buffer.  Query for the right size. */
810 			rc = inode->i_op->getxattr(dentry, XATTR_NAME_SELINUX,
811 						   NULL, 0);
812 			if (rc < 0) {
813 				dput(dentry);
814 				goto out;
815 			}
816 			kfree(context);
817 			len = rc;
818 			context = kmalloc(len, GFP_KERNEL);
819 			if (!context) {
820 				rc = -ENOMEM;
821 				dput(dentry);
822 				goto out;
823 			}
824 			rc = inode->i_op->getxattr(dentry,
825 						   XATTR_NAME_SELINUX,
826 						   context, len);
827 		}
828 		dput(dentry);
829 		if (rc < 0) {
830 			if (rc != -ENODATA) {
831 				printk(KERN_WARNING "%s:  getxattr returned "
832 				       "%d for dev=%s ino=%ld\n", __FUNCTION__,
833 				       -rc, inode->i_sb->s_id, inode->i_ino);
834 				kfree(context);
835 				goto out;
836 			}
837 			/* Map ENODATA to the default file SID */
838 			sid = sbsec->def_sid;
839 			rc = 0;
840 		} else {
841 			rc = security_context_to_sid_default(context, rc, &sid,
842 			                                     sbsec->def_sid);
843 			if (rc) {
844 				printk(KERN_WARNING "%s:  context_to_sid(%s) "
845 				       "returned %d for dev=%s ino=%ld\n",
846 				       __FUNCTION__, context, -rc,
847 				       inode->i_sb->s_id, inode->i_ino);
848 				kfree(context);
849 				/* Leave with the unlabeled SID */
850 				rc = 0;
851 				break;
852 			}
853 		}
854 		kfree(context);
855 		isec->sid = sid;
856 		break;
857 	case SECURITY_FS_USE_TASK:
858 		isec->sid = isec->task_sid;
859 		break;
860 	case SECURITY_FS_USE_TRANS:
861 		/* Default to the fs SID. */
862 		isec->sid = sbsec->sid;
863 
864 		/* Try to obtain a transition SID. */
865 		isec->sclass = inode_mode_to_security_class(inode->i_mode);
866 		rc = security_transition_sid(isec->task_sid,
867 					     sbsec->sid,
868 					     isec->sclass,
869 					     &sid);
870 		if (rc)
871 			goto out;
872 		isec->sid = sid;
873 		break;
874 	default:
875 		/* Default to the fs SID. */
876 		isec->sid = sbsec->sid;
877 
878 		if (sbsec->proc) {
879 			struct proc_inode *proci = PROC_I(inode);
880 			if (proci->pde) {
881 				isec->sclass = inode_mode_to_security_class(inode->i_mode);
882 				rc = selinux_proc_get_sid(proci->pde,
883 							  isec->sclass,
884 							  &sid);
885 				if (rc)
886 					goto out;
887 				isec->sid = sid;
888 			}
889 		}
890 		break;
891 	}
892 
893 	isec->initialized = 1;
894 
895 out:
896 	if (isec->sclass == SECCLASS_FILE)
897 		isec->sclass = inode_mode_to_security_class(inode->i_mode);
898 
899 	if (hold_sem)
900 		up(&isec->sem);
901 	return rc;
902 }
903 
904 /* Convert a Linux signal to an access vector. */
905 static inline u32 signal_to_av(int sig)
906 {
907 	u32 perm = 0;
908 
909 	switch (sig) {
910 	case SIGCHLD:
911 		/* Commonly granted from child to parent. */
912 		perm = PROCESS__SIGCHLD;
913 		break;
914 	case SIGKILL:
915 		/* Cannot be caught or ignored */
916 		perm = PROCESS__SIGKILL;
917 		break;
918 	case SIGSTOP:
919 		/* Cannot be caught or ignored */
920 		perm = PROCESS__SIGSTOP;
921 		break;
922 	default:
923 		/* All other signals. */
924 		perm = PROCESS__SIGNAL;
925 		break;
926 	}
927 
928 	return perm;
929 }
930 
931 /* Check permission betweeen a pair of tasks, e.g. signal checks,
932    fork check, ptrace check, etc. */
933 static int task_has_perm(struct task_struct *tsk1,
934 			 struct task_struct *tsk2,
935 			 u32 perms)
936 {
937 	struct task_security_struct *tsec1, *tsec2;
938 
939 	tsec1 = tsk1->security;
940 	tsec2 = tsk2->security;
941 	return avc_has_perm(tsec1->sid, tsec2->sid,
942 			    SECCLASS_PROCESS, perms, NULL);
943 }
944 
945 /* Check whether a task is allowed to use a capability. */
946 static int task_has_capability(struct task_struct *tsk,
947 			       int cap)
948 {
949 	struct task_security_struct *tsec;
950 	struct avc_audit_data ad;
951 
952 	tsec = tsk->security;
953 
954 	AVC_AUDIT_DATA_INIT(&ad,CAP);
955 	ad.tsk = tsk;
956 	ad.u.cap = cap;
957 
958 	return avc_has_perm(tsec->sid, tsec->sid,
959 			    SECCLASS_CAPABILITY, CAP_TO_MASK(cap), &ad);
960 }
961 
962 /* Check whether a task is allowed to use a system operation. */
963 static int task_has_system(struct task_struct *tsk,
964 			   u32 perms)
965 {
966 	struct task_security_struct *tsec;
967 
968 	tsec = tsk->security;
969 
970 	return avc_has_perm(tsec->sid, SECINITSID_KERNEL,
971 			    SECCLASS_SYSTEM, perms, NULL);
972 }
973 
974 /* Check whether a task has a particular permission to an inode.
975    The 'adp' parameter is optional and allows other audit
976    data to be passed (e.g. the dentry). */
977 static int inode_has_perm(struct task_struct *tsk,
978 			  struct inode *inode,
979 			  u32 perms,
980 			  struct avc_audit_data *adp)
981 {
982 	struct task_security_struct *tsec;
983 	struct inode_security_struct *isec;
984 	struct avc_audit_data ad;
985 
986 	tsec = tsk->security;
987 	isec = inode->i_security;
988 
989 	if (!adp) {
990 		adp = &ad;
991 		AVC_AUDIT_DATA_INIT(&ad, FS);
992 		ad.u.fs.inode = inode;
993 	}
994 
995 	return avc_has_perm(tsec->sid, isec->sid, isec->sclass, perms, adp);
996 }
997 
998 /* Same as inode_has_perm, but pass explicit audit data containing
999    the dentry to help the auditing code to more easily generate the
1000    pathname if needed. */
1001 static inline int dentry_has_perm(struct task_struct *tsk,
1002 				  struct vfsmount *mnt,
1003 				  struct dentry *dentry,
1004 				  u32 av)
1005 {
1006 	struct inode *inode = dentry->d_inode;
1007 	struct avc_audit_data ad;
1008 	AVC_AUDIT_DATA_INIT(&ad,FS);
1009 	ad.u.fs.mnt = mnt;
1010 	ad.u.fs.dentry = dentry;
1011 	return inode_has_perm(tsk, inode, av, &ad);
1012 }
1013 
1014 /* Check whether a task can use an open file descriptor to
1015    access an inode in a given way.  Check access to the
1016    descriptor itself, and then use dentry_has_perm to
1017    check a particular permission to the file.
1018    Access to the descriptor is implicitly granted if it
1019    has the same SID as the process.  If av is zero, then
1020    access to the file is not checked, e.g. for cases
1021    where only the descriptor is affected like seek. */
1022 static inline int file_has_perm(struct task_struct *tsk,
1023 				struct file *file,
1024 				u32 av)
1025 {
1026 	struct task_security_struct *tsec = tsk->security;
1027 	struct file_security_struct *fsec = file->f_security;
1028 	struct vfsmount *mnt = file->f_vfsmnt;
1029 	struct dentry *dentry = file->f_dentry;
1030 	struct inode *inode = dentry->d_inode;
1031 	struct avc_audit_data ad;
1032 	int rc;
1033 
1034 	AVC_AUDIT_DATA_INIT(&ad, FS);
1035 	ad.u.fs.mnt = mnt;
1036 	ad.u.fs.dentry = dentry;
1037 
1038 	if (tsec->sid != fsec->sid) {
1039 		rc = avc_has_perm(tsec->sid, fsec->sid,
1040 				  SECCLASS_FD,
1041 				  FD__USE,
1042 				  &ad);
1043 		if (rc)
1044 			return rc;
1045 	}
1046 
1047 	/* av is zero if only checking access to the descriptor. */
1048 	if (av)
1049 		return inode_has_perm(tsk, inode, av, &ad);
1050 
1051 	return 0;
1052 }
1053 
1054 /* Check whether a task can create a file. */
1055 static int may_create(struct inode *dir,
1056 		      struct dentry *dentry,
1057 		      u16 tclass)
1058 {
1059 	struct task_security_struct *tsec;
1060 	struct inode_security_struct *dsec;
1061 	struct superblock_security_struct *sbsec;
1062 	u32 newsid;
1063 	struct avc_audit_data ad;
1064 	int rc;
1065 
1066 	tsec = current->security;
1067 	dsec = dir->i_security;
1068 	sbsec = dir->i_sb->s_security;
1069 
1070 	AVC_AUDIT_DATA_INIT(&ad, FS);
1071 	ad.u.fs.dentry = dentry;
1072 
1073 	rc = avc_has_perm(tsec->sid, dsec->sid, SECCLASS_DIR,
1074 			  DIR__ADD_NAME | DIR__SEARCH,
1075 			  &ad);
1076 	if (rc)
1077 		return rc;
1078 
1079 	if (tsec->create_sid && sbsec->behavior != SECURITY_FS_USE_MNTPOINT) {
1080 		newsid = tsec->create_sid;
1081 	} else {
1082 		rc = security_transition_sid(tsec->sid, dsec->sid, tclass,
1083 					     &newsid);
1084 		if (rc)
1085 			return rc;
1086 	}
1087 
1088 	rc = avc_has_perm(tsec->sid, newsid, tclass, FILE__CREATE, &ad);
1089 	if (rc)
1090 		return rc;
1091 
1092 	return avc_has_perm(newsid, sbsec->sid,
1093 			    SECCLASS_FILESYSTEM,
1094 			    FILESYSTEM__ASSOCIATE, &ad);
1095 }
1096 
1097 #define MAY_LINK   0
1098 #define MAY_UNLINK 1
1099 #define MAY_RMDIR  2
1100 
1101 /* Check whether a task can link, unlink, or rmdir a file/directory. */
1102 static int may_link(struct inode *dir,
1103 		    struct dentry *dentry,
1104 		    int kind)
1105 
1106 {
1107 	struct task_security_struct *tsec;
1108 	struct inode_security_struct *dsec, *isec;
1109 	struct avc_audit_data ad;
1110 	u32 av;
1111 	int rc;
1112 
1113 	tsec = current->security;
1114 	dsec = dir->i_security;
1115 	isec = dentry->d_inode->i_security;
1116 
1117 	AVC_AUDIT_DATA_INIT(&ad, FS);
1118 	ad.u.fs.dentry = dentry;
1119 
1120 	av = DIR__SEARCH;
1121 	av |= (kind ? DIR__REMOVE_NAME : DIR__ADD_NAME);
1122 	rc = avc_has_perm(tsec->sid, dsec->sid, SECCLASS_DIR, av, &ad);
1123 	if (rc)
1124 		return rc;
1125 
1126 	switch (kind) {
1127 	case MAY_LINK:
1128 		av = FILE__LINK;
1129 		break;
1130 	case MAY_UNLINK:
1131 		av = FILE__UNLINK;
1132 		break;
1133 	case MAY_RMDIR:
1134 		av = DIR__RMDIR;
1135 		break;
1136 	default:
1137 		printk(KERN_WARNING "may_link:  unrecognized kind %d\n", kind);
1138 		return 0;
1139 	}
1140 
1141 	rc = avc_has_perm(tsec->sid, isec->sid, isec->sclass, av, &ad);
1142 	return rc;
1143 }
1144 
1145 static inline int may_rename(struct inode *old_dir,
1146 			     struct dentry *old_dentry,
1147 			     struct inode *new_dir,
1148 			     struct dentry *new_dentry)
1149 {
1150 	struct task_security_struct *tsec;
1151 	struct inode_security_struct *old_dsec, *new_dsec, *old_isec, *new_isec;
1152 	struct avc_audit_data ad;
1153 	u32 av;
1154 	int old_is_dir, new_is_dir;
1155 	int rc;
1156 
1157 	tsec = current->security;
1158 	old_dsec = old_dir->i_security;
1159 	old_isec = old_dentry->d_inode->i_security;
1160 	old_is_dir = S_ISDIR(old_dentry->d_inode->i_mode);
1161 	new_dsec = new_dir->i_security;
1162 
1163 	AVC_AUDIT_DATA_INIT(&ad, FS);
1164 
1165 	ad.u.fs.dentry = old_dentry;
1166 	rc = avc_has_perm(tsec->sid, old_dsec->sid, SECCLASS_DIR,
1167 			  DIR__REMOVE_NAME | DIR__SEARCH, &ad);
1168 	if (rc)
1169 		return rc;
1170 	rc = avc_has_perm(tsec->sid, old_isec->sid,
1171 			  old_isec->sclass, FILE__RENAME, &ad);
1172 	if (rc)
1173 		return rc;
1174 	if (old_is_dir && new_dir != old_dir) {
1175 		rc = avc_has_perm(tsec->sid, old_isec->sid,
1176 				  old_isec->sclass, DIR__REPARENT, &ad);
1177 		if (rc)
1178 			return rc;
1179 	}
1180 
1181 	ad.u.fs.dentry = new_dentry;
1182 	av = DIR__ADD_NAME | DIR__SEARCH;
1183 	if (new_dentry->d_inode)
1184 		av |= DIR__REMOVE_NAME;
1185 	rc = avc_has_perm(tsec->sid, new_dsec->sid, SECCLASS_DIR, av, &ad);
1186 	if (rc)
1187 		return rc;
1188 	if (new_dentry->d_inode) {
1189 		new_isec = new_dentry->d_inode->i_security;
1190 		new_is_dir = S_ISDIR(new_dentry->d_inode->i_mode);
1191 		rc = avc_has_perm(tsec->sid, new_isec->sid,
1192 				  new_isec->sclass,
1193 				  (new_is_dir ? DIR__RMDIR : FILE__UNLINK), &ad);
1194 		if (rc)
1195 			return rc;
1196 	}
1197 
1198 	return 0;
1199 }
1200 
1201 /* Check whether a task can perform a filesystem operation. */
1202 static int superblock_has_perm(struct task_struct *tsk,
1203 			       struct super_block *sb,
1204 			       u32 perms,
1205 			       struct avc_audit_data *ad)
1206 {
1207 	struct task_security_struct *tsec;
1208 	struct superblock_security_struct *sbsec;
1209 
1210 	tsec = tsk->security;
1211 	sbsec = sb->s_security;
1212 	return avc_has_perm(tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM,
1213 			    perms, ad);
1214 }
1215 
1216 /* Convert a Linux mode and permission mask to an access vector. */
1217 static inline u32 file_mask_to_av(int mode, int mask)
1218 {
1219 	u32 av = 0;
1220 
1221 	if ((mode & S_IFMT) != S_IFDIR) {
1222 		if (mask & MAY_EXEC)
1223 			av |= FILE__EXECUTE;
1224 		if (mask & MAY_READ)
1225 			av |= FILE__READ;
1226 
1227 		if (mask & MAY_APPEND)
1228 			av |= FILE__APPEND;
1229 		else if (mask & MAY_WRITE)
1230 			av |= FILE__WRITE;
1231 
1232 	} else {
1233 		if (mask & MAY_EXEC)
1234 			av |= DIR__SEARCH;
1235 		if (mask & MAY_WRITE)
1236 			av |= DIR__WRITE;
1237 		if (mask & MAY_READ)
1238 			av |= DIR__READ;
1239 	}
1240 
1241 	return av;
1242 }
1243 
1244 /* Convert a Linux file to an access vector. */
1245 static inline u32 file_to_av(struct file *file)
1246 {
1247 	u32 av = 0;
1248 
1249 	if (file->f_mode & FMODE_READ)
1250 		av |= FILE__READ;
1251 	if (file->f_mode & FMODE_WRITE) {
1252 		if (file->f_flags & O_APPEND)
1253 			av |= FILE__APPEND;
1254 		else
1255 			av |= FILE__WRITE;
1256 	}
1257 
1258 	return av;
1259 }
1260 
1261 /* Set an inode's SID to a specified value. */
1262 static int inode_security_set_sid(struct inode *inode, u32 sid)
1263 {
1264 	struct inode_security_struct *isec = inode->i_security;
1265 	struct superblock_security_struct *sbsec = inode->i_sb->s_security;
1266 
1267 	if (!sbsec->initialized) {
1268 		/* Defer initialization to selinux_complete_init. */
1269 		return 0;
1270 	}
1271 
1272 	down(&isec->sem);
1273 	isec->sclass = inode_mode_to_security_class(inode->i_mode);
1274 	isec->sid = sid;
1275 	isec->initialized = 1;
1276 	up(&isec->sem);
1277 	return 0;
1278 }
1279 
1280 /* Hook functions begin here. */
1281 
1282 static int selinux_ptrace(struct task_struct *parent, struct task_struct *child)
1283 {
1284 	struct task_security_struct *psec = parent->security;
1285 	struct task_security_struct *csec = child->security;
1286 	int rc;
1287 
1288 	rc = secondary_ops->ptrace(parent,child);
1289 	if (rc)
1290 		return rc;
1291 
1292 	rc = task_has_perm(parent, child, PROCESS__PTRACE);
1293 	/* Save the SID of the tracing process for later use in apply_creds. */
1294 	if (!rc)
1295 		csec->ptrace_sid = psec->sid;
1296 	return rc;
1297 }
1298 
1299 static int selinux_capget(struct task_struct *target, kernel_cap_t *effective,
1300                           kernel_cap_t *inheritable, kernel_cap_t *permitted)
1301 {
1302 	int error;
1303 
1304 	error = task_has_perm(current, target, PROCESS__GETCAP);
1305 	if (error)
1306 		return error;
1307 
1308 	return secondary_ops->capget(target, effective, inheritable, permitted);
1309 }
1310 
1311 static int selinux_capset_check(struct task_struct *target, kernel_cap_t *effective,
1312                                 kernel_cap_t *inheritable, kernel_cap_t *permitted)
1313 {
1314 	int error;
1315 
1316 	error = secondary_ops->capset_check(target, effective, inheritable, permitted);
1317 	if (error)
1318 		return error;
1319 
1320 	return task_has_perm(current, target, PROCESS__SETCAP);
1321 }
1322 
1323 static void selinux_capset_set(struct task_struct *target, kernel_cap_t *effective,
1324                                kernel_cap_t *inheritable, kernel_cap_t *permitted)
1325 {
1326 	secondary_ops->capset_set(target, effective, inheritable, permitted);
1327 }
1328 
1329 static int selinux_capable(struct task_struct *tsk, int cap)
1330 {
1331 	int rc;
1332 
1333 	rc = secondary_ops->capable(tsk, cap);
1334 	if (rc)
1335 		return rc;
1336 
1337 	return task_has_capability(tsk,cap);
1338 }
1339 
1340 static int selinux_sysctl(ctl_table *table, int op)
1341 {
1342 	int error = 0;
1343 	u32 av;
1344 	struct task_security_struct *tsec;
1345 	u32 tsid;
1346 	int rc;
1347 
1348 	rc = secondary_ops->sysctl(table, op);
1349 	if (rc)
1350 		return rc;
1351 
1352 	tsec = current->security;
1353 
1354 	rc = selinux_proc_get_sid(table->de, (op == 001) ?
1355 	                          SECCLASS_DIR : SECCLASS_FILE, &tsid);
1356 	if (rc) {
1357 		/* Default to the well-defined sysctl SID. */
1358 		tsid = SECINITSID_SYSCTL;
1359 	}
1360 
1361 	/* The op values are "defined" in sysctl.c, thereby creating
1362 	 * a bad coupling between this module and sysctl.c */
1363 	if(op == 001) {
1364 		error = avc_has_perm(tsec->sid, tsid,
1365 				     SECCLASS_DIR, DIR__SEARCH, NULL);
1366 	} else {
1367 		av = 0;
1368 		if (op & 004)
1369 			av |= FILE__READ;
1370 		if (op & 002)
1371 			av |= FILE__WRITE;
1372 		if (av)
1373 			error = avc_has_perm(tsec->sid, tsid,
1374 					     SECCLASS_FILE, av, NULL);
1375         }
1376 
1377 	return error;
1378 }
1379 
1380 static int selinux_quotactl(int cmds, int type, int id, struct super_block *sb)
1381 {
1382 	int rc = 0;
1383 
1384 	if (!sb)
1385 		return 0;
1386 
1387 	switch (cmds) {
1388 		case Q_SYNC:
1389 		case Q_QUOTAON:
1390 		case Q_QUOTAOFF:
1391 	        case Q_SETINFO:
1392 		case Q_SETQUOTA:
1393 			rc = superblock_has_perm(current,
1394 						 sb,
1395 						 FILESYSTEM__QUOTAMOD, NULL);
1396 			break;
1397 	        case Q_GETFMT:
1398 	        case Q_GETINFO:
1399 		case Q_GETQUOTA:
1400 			rc = superblock_has_perm(current,
1401 						 sb,
1402 						 FILESYSTEM__QUOTAGET, NULL);
1403 			break;
1404 		default:
1405 			rc = 0;  /* let the kernel handle invalid cmds */
1406 			break;
1407 	}
1408 	return rc;
1409 }
1410 
1411 static int selinux_quota_on(struct dentry *dentry)
1412 {
1413 	return dentry_has_perm(current, NULL, dentry, FILE__QUOTAON);
1414 }
1415 
1416 static int selinux_syslog(int type)
1417 {
1418 	int rc;
1419 
1420 	rc = secondary_ops->syslog(type);
1421 	if (rc)
1422 		return rc;
1423 
1424 	switch (type) {
1425 		case 3:         /* Read last kernel messages */
1426 		case 10:        /* Return size of the log buffer */
1427 			rc = task_has_system(current, SYSTEM__SYSLOG_READ);
1428 			break;
1429 		case 6:         /* Disable logging to console */
1430 		case 7:         /* Enable logging to console */
1431 		case 8:		/* Set level of messages printed to console */
1432 			rc = task_has_system(current, SYSTEM__SYSLOG_CONSOLE);
1433 			break;
1434 		case 0:         /* Close log */
1435 		case 1:         /* Open log */
1436 		case 2:         /* Read from log */
1437 		case 4:         /* Read/clear last kernel messages */
1438 		case 5:         /* Clear ring buffer */
1439 		default:
1440 			rc = task_has_system(current, SYSTEM__SYSLOG_MOD);
1441 			break;
1442 	}
1443 	return rc;
1444 }
1445 
1446 /*
1447  * Check that a process has enough memory to allocate a new virtual
1448  * mapping. 0 means there is enough memory for the allocation to
1449  * succeed and -ENOMEM implies there is not.
1450  *
1451  * Note that secondary_ops->capable and task_has_perm_noaudit return 0
1452  * if the capability is granted, but __vm_enough_memory requires 1 if
1453  * the capability is granted.
1454  *
1455  * Do not audit the selinux permission check, as this is applied to all
1456  * processes that allocate mappings.
1457  */
1458 static int selinux_vm_enough_memory(long pages)
1459 {
1460 	int rc, cap_sys_admin = 0;
1461 	struct task_security_struct *tsec = current->security;
1462 
1463 	rc = secondary_ops->capable(current, CAP_SYS_ADMIN);
1464 	if (rc == 0)
1465 		rc = avc_has_perm_noaudit(tsec->sid, tsec->sid,
1466 					SECCLASS_CAPABILITY,
1467 					CAP_TO_MASK(CAP_SYS_ADMIN),
1468 					NULL);
1469 
1470 	if (rc == 0)
1471 		cap_sys_admin = 1;
1472 
1473 	return __vm_enough_memory(pages, cap_sys_admin);
1474 }
1475 
1476 /* binprm security operations */
1477 
1478 static int selinux_bprm_alloc_security(struct linux_binprm *bprm)
1479 {
1480 	struct bprm_security_struct *bsec;
1481 
1482 	bsec = kzalloc(sizeof(struct bprm_security_struct), GFP_KERNEL);
1483 	if (!bsec)
1484 		return -ENOMEM;
1485 
1486 	bsec->magic = SELINUX_MAGIC;
1487 	bsec->bprm = bprm;
1488 	bsec->sid = SECINITSID_UNLABELED;
1489 	bsec->set = 0;
1490 
1491 	bprm->security = bsec;
1492 	return 0;
1493 }
1494 
1495 static int selinux_bprm_set_security(struct linux_binprm *bprm)
1496 {
1497 	struct task_security_struct *tsec;
1498 	struct inode *inode = bprm->file->f_dentry->d_inode;
1499 	struct inode_security_struct *isec;
1500 	struct bprm_security_struct *bsec;
1501 	u32 newsid;
1502 	struct avc_audit_data ad;
1503 	int rc;
1504 
1505 	rc = secondary_ops->bprm_set_security(bprm);
1506 	if (rc)
1507 		return rc;
1508 
1509 	bsec = bprm->security;
1510 
1511 	if (bsec->set)
1512 		return 0;
1513 
1514 	tsec = current->security;
1515 	isec = inode->i_security;
1516 
1517 	/* Default to the current task SID. */
1518 	bsec->sid = tsec->sid;
1519 
1520 	/* Reset create SID on execve. */
1521 	tsec->create_sid = 0;
1522 
1523 	if (tsec->exec_sid) {
1524 		newsid = tsec->exec_sid;
1525 		/* Reset exec SID on execve. */
1526 		tsec->exec_sid = 0;
1527 	} else {
1528 		/* Check for a default transition on this program. */
1529 		rc = security_transition_sid(tsec->sid, isec->sid,
1530 		                             SECCLASS_PROCESS, &newsid);
1531 		if (rc)
1532 			return rc;
1533 	}
1534 
1535 	AVC_AUDIT_DATA_INIT(&ad, FS);
1536 	ad.u.fs.mnt = bprm->file->f_vfsmnt;
1537 	ad.u.fs.dentry = bprm->file->f_dentry;
1538 
1539 	if (bprm->file->f_vfsmnt->mnt_flags & MNT_NOSUID)
1540 		newsid = tsec->sid;
1541 
1542         if (tsec->sid == newsid) {
1543 		rc = avc_has_perm(tsec->sid, isec->sid,
1544 				  SECCLASS_FILE, FILE__EXECUTE_NO_TRANS, &ad);
1545 		if (rc)
1546 			return rc;
1547 	} else {
1548 		/* Check permissions for the transition. */
1549 		rc = avc_has_perm(tsec->sid, newsid,
1550 				  SECCLASS_PROCESS, PROCESS__TRANSITION, &ad);
1551 		if (rc)
1552 			return rc;
1553 
1554 		rc = avc_has_perm(newsid, isec->sid,
1555 				  SECCLASS_FILE, FILE__ENTRYPOINT, &ad);
1556 		if (rc)
1557 			return rc;
1558 
1559 		/* Clear any possibly unsafe personality bits on exec: */
1560 		current->personality &= ~PER_CLEAR_ON_SETID;
1561 
1562 		/* Set the security field to the new SID. */
1563 		bsec->sid = newsid;
1564 	}
1565 
1566 	bsec->set = 1;
1567 	return 0;
1568 }
1569 
1570 static int selinux_bprm_check_security (struct linux_binprm *bprm)
1571 {
1572 	return secondary_ops->bprm_check_security(bprm);
1573 }
1574 
1575 
1576 static int selinux_bprm_secureexec (struct linux_binprm *bprm)
1577 {
1578 	struct task_security_struct *tsec = current->security;
1579 	int atsecure = 0;
1580 
1581 	if (tsec->osid != tsec->sid) {
1582 		/* Enable secure mode for SIDs transitions unless
1583 		   the noatsecure permission is granted between
1584 		   the two SIDs, i.e. ahp returns 0. */
1585 		atsecure = avc_has_perm(tsec->osid, tsec->sid,
1586 					 SECCLASS_PROCESS,
1587 					 PROCESS__NOATSECURE, NULL);
1588 	}
1589 
1590 	return (atsecure || secondary_ops->bprm_secureexec(bprm));
1591 }
1592 
1593 static void selinux_bprm_free_security(struct linux_binprm *bprm)
1594 {
1595 	kfree(bprm->security);
1596 	bprm->security = NULL;
1597 }
1598 
1599 extern struct vfsmount *selinuxfs_mount;
1600 extern struct dentry *selinux_null;
1601 
1602 /* Derived from fs/exec.c:flush_old_files. */
1603 static inline void flush_unauthorized_files(struct files_struct * files)
1604 {
1605 	struct avc_audit_data ad;
1606 	struct file *file, *devnull = NULL;
1607 	struct tty_struct *tty = current->signal->tty;
1608 	struct fdtable *fdt;
1609 	long j = -1;
1610 
1611 	if (tty) {
1612 		file_list_lock();
1613 		file = list_entry(tty->tty_files.next, typeof(*file), f_u.fu_list);
1614 		if (file) {
1615 			/* Revalidate access to controlling tty.
1616 			   Use inode_has_perm on the tty inode directly rather
1617 			   than using file_has_perm, as this particular open
1618 			   file may belong to another process and we are only
1619 			   interested in the inode-based check here. */
1620 			struct inode *inode = file->f_dentry->d_inode;
1621 			if (inode_has_perm(current, inode,
1622 					   FILE__READ | FILE__WRITE, NULL)) {
1623 				/* Reset controlling tty. */
1624 				current->signal->tty = NULL;
1625 				current->signal->tty_old_pgrp = 0;
1626 			}
1627 		}
1628 		file_list_unlock();
1629 	}
1630 
1631 	/* Revalidate access to inherited open files. */
1632 
1633 	AVC_AUDIT_DATA_INIT(&ad,FS);
1634 
1635 	spin_lock(&files->file_lock);
1636 	for (;;) {
1637 		unsigned long set, i;
1638 		int fd;
1639 
1640 		j++;
1641 		i = j * __NFDBITS;
1642 		fdt = files_fdtable(files);
1643 		if (i >= fdt->max_fds || i >= fdt->max_fdset)
1644 			break;
1645 		set = fdt->open_fds->fds_bits[j];
1646 		if (!set)
1647 			continue;
1648 		spin_unlock(&files->file_lock);
1649 		for ( ; set ; i++,set >>= 1) {
1650 			if (set & 1) {
1651 				file = fget(i);
1652 				if (!file)
1653 					continue;
1654 				if (file_has_perm(current,
1655 						  file,
1656 						  file_to_av(file))) {
1657 					sys_close(i);
1658 					fd = get_unused_fd();
1659 					if (fd != i) {
1660 						if (fd >= 0)
1661 							put_unused_fd(fd);
1662 						fput(file);
1663 						continue;
1664 					}
1665 					if (devnull) {
1666 						get_file(devnull);
1667 					} else {
1668 						devnull = dentry_open(dget(selinux_null), mntget(selinuxfs_mount), O_RDWR);
1669 						if (!devnull) {
1670 							put_unused_fd(fd);
1671 							fput(file);
1672 							continue;
1673 						}
1674 					}
1675 					fd_install(fd, devnull);
1676 				}
1677 				fput(file);
1678 			}
1679 		}
1680 		spin_lock(&files->file_lock);
1681 
1682 	}
1683 	spin_unlock(&files->file_lock);
1684 }
1685 
1686 static void selinux_bprm_apply_creds(struct linux_binprm *bprm, int unsafe)
1687 {
1688 	struct task_security_struct *tsec;
1689 	struct bprm_security_struct *bsec;
1690 	u32 sid;
1691 	int rc;
1692 
1693 	secondary_ops->bprm_apply_creds(bprm, unsafe);
1694 
1695 	tsec = current->security;
1696 
1697 	bsec = bprm->security;
1698 	sid = bsec->sid;
1699 
1700 	tsec->osid = tsec->sid;
1701 	bsec->unsafe = 0;
1702 	if (tsec->sid != sid) {
1703 		/* Check for shared state.  If not ok, leave SID
1704 		   unchanged and kill. */
1705 		if (unsafe & LSM_UNSAFE_SHARE) {
1706 			rc = avc_has_perm(tsec->sid, sid, SECCLASS_PROCESS,
1707 					PROCESS__SHARE, NULL);
1708 			if (rc) {
1709 				bsec->unsafe = 1;
1710 				return;
1711 			}
1712 		}
1713 
1714 		/* Check for ptracing, and update the task SID if ok.
1715 		   Otherwise, leave SID unchanged and kill. */
1716 		if (unsafe & (LSM_UNSAFE_PTRACE | LSM_UNSAFE_PTRACE_CAP)) {
1717 			rc = avc_has_perm(tsec->ptrace_sid, sid,
1718 					  SECCLASS_PROCESS, PROCESS__PTRACE,
1719 					  NULL);
1720 			if (rc) {
1721 				bsec->unsafe = 1;
1722 				return;
1723 			}
1724 		}
1725 		tsec->sid = sid;
1726 	}
1727 }
1728 
1729 /*
1730  * called after apply_creds without the task lock held
1731  */
1732 static void selinux_bprm_post_apply_creds(struct linux_binprm *bprm)
1733 {
1734 	struct task_security_struct *tsec;
1735 	struct rlimit *rlim, *initrlim;
1736 	struct itimerval itimer;
1737 	struct bprm_security_struct *bsec;
1738 	int rc, i;
1739 
1740 	tsec = current->security;
1741 	bsec = bprm->security;
1742 
1743 	if (bsec->unsafe) {
1744 		force_sig_specific(SIGKILL, current);
1745 		return;
1746 	}
1747 	if (tsec->osid == tsec->sid)
1748 		return;
1749 
1750 	/* Close files for which the new task SID is not authorized. */
1751 	flush_unauthorized_files(current->files);
1752 
1753 	/* Check whether the new SID can inherit signal state
1754 	   from the old SID.  If not, clear itimers to avoid
1755 	   subsequent signal generation and flush and unblock
1756 	   signals. This must occur _after_ the task SID has
1757 	  been updated so that any kill done after the flush
1758 	  will be checked against the new SID. */
1759 	rc = avc_has_perm(tsec->osid, tsec->sid, SECCLASS_PROCESS,
1760 			  PROCESS__SIGINH, NULL);
1761 	if (rc) {
1762 		memset(&itimer, 0, sizeof itimer);
1763 		for (i = 0; i < 3; i++)
1764 			do_setitimer(i, &itimer, NULL);
1765 		flush_signals(current);
1766 		spin_lock_irq(&current->sighand->siglock);
1767 		flush_signal_handlers(current, 1);
1768 		sigemptyset(&current->blocked);
1769 		recalc_sigpending();
1770 		spin_unlock_irq(&current->sighand->siglock);
1771 	}
1772 
1773 	/* Check whether the new SID can inherit resource limits
1774 	   from the old SID.  If not, reset all soft limits to
1775 	   the lower of the current task's hard limit and the init
1776 	   task's soft limit.  Note that the setting of hard limits
1777 	   (even to lower them) can be controlled by the setrlimit
1778 	   check. The inclusion of the init task's soft limit into
1779 	   the computation is to avoid resetting soft limits higher
1780 	   than the default soft limit for cases where the default
1781 	   is lower than the hard limit, e.g. RLIMIT_CORE or
1782 	   RLIMIT_STACK.*/
1783 	rc = avc_has_perm(tsec->osid, tsec->sid, SECCLASS_PROCESS,
1784 			  PROCESS__RLIMITINH, NULL);
1785 	if (rc) {
1786 		for (i = 0; i < RLIM_NLIMITS; i++) {
1787 			rlim = current->signal->rlim + i;
1788 			initrlim = init_task.signal->rlim+i;
1789 			rlim->rlim_cur = min(rlim->rlim_max,initrlim->rlim_cur);
1790 		}
1791 		if (current->signal->rlim[RLIMIT_CPU].rlim_cur != RLIM_INFINITY) {
1792 			/*
1793 			 * This will cause RLIMIT_CPU calculations
1794 			 * to be refigured.
1795 			 */
1796 			current->it_prof_expires = jiffies_to_cputime(1);
1797 		}
1798 	}
1799 
1800 	/* Wake up the parent if it is waiting so that it can
1801 	   recheck wait permission to the new task SID. */
1802 	wake_up_interruptible(&current->parent->signal->wait_chldexit);
1803 }
1804 
1805 /* superblock security operations */
1806 
1807 static int selinux_sb_alloc_security(struct super_block *sb)
1808 {
1809 	return superblock_alloc_security(sb);
1810 }
1811 
1812 static void selinux_sb_free_security(struct super_block *sb)
1813 {
1814 	superblock_free_security(sb);
1815 }
1816 
1817 static inline int match_prefix(char *prefix, int plen, char *option, int olen)
1818 {
1819 	if (plen > olen)
1820 		return 0;
1821 
1822 	return !memcmp(prefix, option, plen);
1823 }
1824 
1825 static inline int selinux_option(char *option, int len)
1826 {
1827 	return (match_prefix("context=", sizeof("context=")-1, option, len) ||
1828 	        match_prefix("fscontext=", sizeof("fscontext=")-1, option, len) ||
1829 	        match_prefix("defcontext=", sizeof("defcontext=")-1, option, len));
1830 }
1831 
1832 static inline void take_option(char **to, char *from, int *first, int len)
1833 {
1834 	if (!*first) {
1835 		**to = ',';
1836 		*to += 1;
1837 	}
1838 	else
1839 		*first = 0;
1840 	memcpy(*to, from, len);
1841 	*to += len;
1842 }
1843 
1844 static int selinux_sb_copy_data(struct file_system_type *type, void *orig, void *copy)
1845 {
1846 	int fnosec, fsec, rc = 0;
1847 	char *in_save, *in_curr, *in_end;
1848 	char *sec_curr, *nosec_save, *nosec;
1849 
1850 	in_curr = orig;
1851 	sec_curr = copy;
1852 
1853 	/* Binary mount data: just copy */
1854 	if (type->fs_flags & FS_BINARY_MOUNTDATA) {
1855 		copy_page(sec_curr, in_curr);
1856 		goto out;
1857 	}
1858 
1859 	nosec = (char *)get_zeroed_page(GFP_KERNEL);
1860 	if (!nosec) {
1861 		rc = -ENOMEM;
1862 		goto out;
1863 	}
1864 
1865 	nosec_save = nosec;
1866 	fnosec = fsec = 1;
1867 	in_save = in_end = orig;
1868 
1869 	do {
1870 		if (*in_end == ',' || *in_end == '\0') {
1871 			int len = in_end - in_curr;
1872 
1873 			if (selinux_option(in_curr, len))
1874 				take_option(&sec_curr, in_curr, &fsec, len);
1875 			else
1876 				take_option(&nosec, in_curr, &fnosec, len);
1877 
1878 			in_curr = in_end + 1;
1879 		}
1880 	} while (*in_end++);
1881 
1882 	strcpy(in_save, nosec_save);
1883 	free_page((unsigned long)nosec_save);
1884 out:
1885 	return rc;
1886 }
1887 
1888 static int selinux_sb_kern_mount(struct super_block *sb, void *data)
1889 {
1890 	struct avc_audit_data ad;
1891 	int rc;
1892 
1893 	rc = superblock_doinit(sb, data);
1894 	if (rc)
1895 		return rc;
1896 
1897 	AVC_AUDIT_DATA_INIT(&ad,FS);
1898 	ad.u.fs.dentry = sb->s_root;
1899 	return superblock_has_perm(current, sb, FILESYSTEM__MOUNT, &ad);
1900 }
1901 
1902 static int selinux_sb_statfs(struct super_block *sb)
1903 {
1904 	struct avc_audit_data ad;
1905 
1906 	AVC_AUDIT_DATA_INIT(&ad,FS);
1907 	ad.u.fs.dentry = sb->s_root;
1908 	return superblock_has_perm(current, sb, FILESYSTEM__GETATTR, &ad);
1909 }
1910 
1911 static int selinux_mount(char * dev_name,
1912                          struct nameidata *nd,
1913                          char * type,
1914                          unsigned long flags,
1915                          void * data)
1916 {
1917 	int rc;
1918 
1919 	rc = secondary_ops->sb_mount(dev_name, nd, type, flags, data);
1920 	if (rc)
1921 		return rc;
1922 
1923 	if (flags & MS_REMOUNT)
1924 		return superblock_has_perm(current, nd->mnt->mnt_sb,
1925 		                           FILESYSTEM__REMOUNT, NULL);
1926 	else
1927 		return dentry_has_perm(current, nd->mnt, nd->dentry,
1928 		                       FILE__MOUNTON);
1929 }
1930 
1931 static int selinux_umount(struct vfsmount *mnt, int flags)
1932 {
1933 	int rc;
1934 
1935 	rc = secondary_ops->sb_umount(mnt, flags);
1936 	if (rc)
1937 		return rc;
1938 
1939 	return superblock_has_perm(current,mnt->mnt_sb,
1940 	                           FILESYSTEM__UNMOUNT,NULL);
1941 }
1942 
1943 /* inode security operations */
1944 
1945 static int selinux_inode_alloc_security(struct inode *inode)
1946 {
1947 	return inode_alloc_security(inode);
1948 }
1949 
1950 static void selinux_inode_free_security(struct inode *inode)
1951 {
1952 	inode_free_security(inode);
1953 }
1954 
1955 static int selinux_inode_init_security(struct inode *inode, struct inode *dir,
1956 				       char **name, void **value,
1957 				       size_t *len)
1958 {
1959 	struct task_security_struct *tsec;
1960 	struct inode_security_struct *dsec;
1961 	struct superblock_security_struct *sbsec;
1962 	struct inode_security_struct *isec;
1963 	u32 newsid, clen;
1964 	int rc;
1965 	char *namep = NULL, *context;
1966 
1967 	tsec = current->security;
1968 	dsec = dir->i_security;
1969 	sbsec = dir->i_sb->s_security;
1970 	isec = inode->i_security;
1971 
1972 	if (tsec->create_sid && sbsec->behavior != SECURITY_FS_USE_MNTPOINT) {
1973 		newsid = tsec->create_sid;
1974 	} else {
1975 		rc = security_transition_sid(tsec->sid, dsec->sid,
1976 					     inode_mode_to_security_class(inode->i_mode),
1977 					     &newsid);
1978 		if (rc) {
1979 			printk(KERN_WARNING "%s:  "
1980 			       "security_transition_sid failed, rc=%d (dev=%s "
1981 			       "ino=%ld)\n",
1982 			       __FUNCTION__,
1983 			       -rc, inode->i_sb->s_id, inode->i_ino);
1984 			return rc;
1985 		}
1986 	}
1987 
1988 	inode_security_set_sid(inode, newsid);
1989 
1990 	if (sbsec->behavior == SECURITY_FS_USE_MNTPOINT)
1991 		return -EOPNOTSUPP;
1992 
1993 	if (name) {
1994 		namep = kstrdup(XATTR_SELINUX_SUFFIX, GFP_KERNEL);
1995 		if (!namep)
1996 			return -ENOMEM;
1997 		*name = namep;
1998 	}
1999 
2000 	if (value && len) {
2001 		rc = security_sid_to_context(newsid, &context, &clen);
2002 		if (rc) {
2003 			kfree(namep);
2004 			return rc;
2005 		}
2006 		*value = context;
2007 		*len = clen;
2008 	}
2009 
2010 	return 0;
2011 }
2012 
2013 static int selinux_inode_create(struct inode *dir, struct dentry *dentry, int mask)
2014 {
2015 	return may_create(dir, dentry, SECCLASS_FILE);
2016 }
2017 
2018 static int selinux_inode_link(struct dentry *old_dentry, struct inode *dir, struct dentry *new_dentry)
2019 {
2020 	int rc;
2021 
2022 	rc = secondary_ops->inode_link(old_dentry,dir,new_dentry);
2023 	if (rc)
2024 		return rc;
2025 	return may_link(dir, old_dentry, MAY_LINK);
2026 }
2027 
2028 static int selinux_inode_unlink(struct inode *dir, struct dentry *dentry)
2029 {
2030 	int rc;
2031 
2032 	rc = secondary_ops->inode_unlink(dir, dentry);
2033 	if (rc)
2034 		return rc;
2035 	return may_link(dir, dentry, MAY_UNLINK);
2036 }
2037 
2038 static int selinux_inode_symlink(struct inode *dir, struct dentry *dentry, const char *name)
2039 {
2040 	return may_create(dir, dentry, SECCLASS_LNK_FILE);
2041 }
2042 
2043 static int selinux_inode_mkdir(struct inode *dir, struct dentry *dentry, int mask)
2044 {
2045 	return may_create(dir, dentry, SECCLASS_DIR);
2046 }
2047 
2048 static int selinux_inode_rmdir(struct inode *dir, struct dentry *dentry)
2049 {
2050 	return may_link(dir, dentry, MAY_RMDIR);
2051 }
2052 
2053 static int selinux_inode_mknod(struct inode *dir, struct dentry *dentry, int mode, dev_t dev)
2054 {
2055 	int rc;
2056 
2057 	rc = secondary_ops->inode_mknod(dir, dentry, mode, dev);
2058 	if (rc)
2059 		return rc;
2060 
2061 	return may_create(dir, dentry, inode_mode_to_security_class(mode));
2062 }
2063 
2064 static int selinux_inode_rename(struct inode *old_inode, struct dentry *old_dentry,
2065                                 struct inode *new_inode, struct dentry *new_dentry)
2066 {
2067 	return may_rename(old_inode, old_dentry, new_inode, new_dentry);
2068 }
2069 
2070 static int selinux_inode_readlink(struct dentry *dentry)
2071 {
2072 	return dentry_has_perm(current, NULL, dentry, FILE__READ);
2073 }
2074 
2075 static int selinux_inode_follow_link(struct dentry *dentry, struct nameidata *nameidata)
2076 {
2077 	int rc;
2078 
2079 	rc = secondary_ops->inode_follow_link(dentry,nameidata);
2080 	if (rc)
2081 		return rc;
2082 	return dentry_has_perm(current, NULL, dentry, FILE__READ);
2083 }
2084 
2085 static int selinux_inode_permission(struct inode *inode, int mask,
2086 				    struct nameidata *nd)
2087 {
2088 	int rc;
2089 
2090 	rc = secondary_ops->inode_permission(inode, mask, nd);
2091 	if (rc)
2092 		return rc;
2093 
2094 	if (!mask) {
2095 		/* No permission to check.  Existence test. */
2096 		return 0;
2097 	}
2098 
2099 	return inode_has_perm(current, inode,
2100 			       file_mask_to_av(inode->i_mode, mask), NULL);
2101 }
2102 
2103 static int selinux_inode_setattr(struct dentry *dentry, struct iattr *iattr)
2104 {
2105 	int rc;
2106 
2107 	rc = secondary_ops->inode_setattr(dentry, iattr);
2108 	if (rc)
2109 		return rc;
2110 
2111 	if (iattr->ia_valid & ATTR_FORCE)
2112 		return 0;
2113 
2114 	if (iattr->ia_valid & (ATTR_MODE | ATTR_UID | ATTR_GID |
2115 			       ATTR_ATIME_SET | ATTR_MTIME_SET))
2116 		return dentry_has_perm(current, NULL, dentry, FILE__SETATTR);
2117 
2118 	return dentry_has_perm(current, NULL, dentry, FILE__WRITE);
2119 }
2120 
2121 static int selinux_inode_getattr(struct vfsmount *mnt, struct dentry *dentry)
2122 {
2123 	return dentry_has_perm(current, mnt, dentry, FILE__GETATTR);
2124 }
2125 
2126 static int selinux_inode_setxattr(struct dentry *dentry, char *name, void *value, size_t size, int flags)
2127 {
2128 	struct task_security_struct *tsec = current->security;
2129 	struct inode *inode = dentry->d_inode;
2130 	struct inode_security_struct *isec = inode->i_security;
2131 	struct superblock_security_struct *sbsec;
2132 	struct avc_audit_data ad;
2133 	u32 newsid;
2134 	int rc = 0;
2135 
2136 	if (strcmp(name, XATTR_NAME_SELINUX)) {
2137 		if (!strncmp(name, XATTR_SECURITY_PREFIX,
2138 			     sizeof XATTR_SECURITY_PREFIX - 1) &&
2139 		    !capable(CAP_SYS_ADMIN)) {
2140 			/* A different attribute in the security namespace.
2141 			   Restrict to administrator. */
2142 			return -EPERM;
2143 		}
2144 
2145 		/* Not an attribute we recognize, so just check the
2146 		   ordinary setattr permission. */
2147 		return dentry_has_perm(current, NULL, dentry, FILE__SETATTR);
2148 	}
2149 
2150 	sbsec = inode->i_sb->s_security;
2151 	if (sbsec->behavior == SECURITY_FS_USE_MNTPOINT)
2152 		return -EOPNOTSUPP;
2153 
2154 	if ((current->fsuid != inode->i_uid) && !capable(CAP_FOWNER))
2155 		return -EPERM;
2156 
2157 	AVC_AUDIT_DATA_INIT(&ad,FS);
2158 	ad.u.fs.dentry = dentry;
2159 
2160 	rc = avc_has_perm(tsec->sid, isec->sid, isec->sclass,
2161 			  FILE__RELABELFROM, &ad);
2162 	if (rc)
2163 		return rc;
2164 
2165 	rc = security_context_to_sid(value, size, &newsid);
2166 	if (rc)
2167 		return rc;
2168 
2169 	rc = avc_has_perm(tsec->sid, newsid, isec->sclass,
2170 			  FILE__RELABELTO, &ad);
2171 	if (rc)
2172 		return rc;
2173 
2174 	rc = security_validate_transition(isec->sid, newsid, tsec->sid,
2175 	                                  isec->sclass);
2176 	if (rc)
2177 		return rc;
2178 
2179 	return avc_has_perm(newsid,
2180 			    sbsec->sid,
2181 			    SECCLASS_FILESYSTEM,
2182 			    FILESYSTEM__ASSOCIATE,
2183 			    &ad);
2184 }
2185 
2186 static void selinux_inode_post_setxattr(struct dentry *dentry, char *name,
2187                                         void *value, size_t size, int flags)
2188 {
2189 	struct inode *inode = dentry->d_inode;
2190 	struct inode_security_struct *isec = inode->i_security;
2191 	u32 newsid;
2192 	int rc;
2193 
2194 	if (strcmp(name, XATTR_NAME_SELINUX)) {
2195 		/* Not an attribute we recognize, so nothing to do. */
2196 		return;
2197 	}
2198 
2199 	rc = security_context_to_sid(value, size, &newsid);
2200 	if (rc) {
2201 		printk(KERN_WARNING "%s:  unable to obtain SID for context "
2202 		       "%s, rc=%d\n", __FUNCTION__, (char*)value, -rc);
2203 		return;
2204 	}
2205 
2206 	isec->sid = newsid;
2207 	return;
2208 }
2209 
2210 static int selinux_inode_getxattr (struct dentry *dentry, char *name)
2211 {
2212 	return dentry_has_perm(current, NULL, dentry, FILE__GETATTR);
2213 }
2214 
2215 static int selinux_inode_listxattr (struct dentry *dentry)
2216 {
2217 	return dentry_has_perm(current, NULL, dentry, FILE__GETATTR);
2218 }
2219 
2220 static int selinux_inode_removexattr (struct dentry *dentry, char *name)
2221 {
2222 	if (strcmp(name, XATTR_NAME_SELINUX)) {
2223 		if (!strncmp(name, XATTR_SECURITY_PREFIX,
2224 			     sizeof XATTR_SECURITY_PREFIX - 1) &&
2225 		    !capable(CAP_SYS_ADMIN)) {
2226 			/* A different attribute in the security namespace.
2227 			   Restrict to administrator. */
2228 			return -EPERM;
2229 		}
2230 
2231 		/* Not an attribute we recognize, so just check the
2232 		   ordinary setattr permission. Might want a separate
2233 		   permission for removexattr. */
2234 		return dentry_has_perm(current, NULL, dentry, FILE__SETATTR);
2235 	}
2236 
2237 	/* No one is allowed to remove a SELinux security label.
2238 	   You can change the label, but all data must be labeled. */
2239 	return -EACCES;
2240 }
2241 
2242 /*
2243  * Copy the in-core inode security context value to the user.  If the
2244  * getxattr() prior to this succeeded, check to see if we need to
2245  * canonicalize the value to be finally returned to the user.
2246  *
2247  * Permission check is handled by selinux_inode_getxattr hook.
2248  */
2249 static int selinux_inode_getsecurity(struct inode *inode, const char *name, void *buffer, size_t size, int err)
2250 {
2251 	struct inode_security_struct *isec = inode->i_security;
2252 	char *context;
2253 	unsigned len;
2254 	int rc;
2255 
2256 	if (strcmp(name, XATTR_SELINUX_SUFFIX)) {
2257 		rc = -EOPNOTSUPP;
2258 		goto out;
2259 	}
2260 
2261 	rc = security_sid_to_context(isec->sid, &context, &len);
2262 	if (rc)
2263 		goto out;
2264 
2265 	/* Probe for required buffer size */
2266 	if (!buffer || !size) {
2267 		rc = len;
2268 		goto out_free;
2269 	}
2270 
2271 	if (size < len) {
2272 		rc = -ERANGE;
2273 		goto out_free;
2274 	}
2275 
2276 	if (err > 0) {
2277 		if ((len == err) && !(memcmp(context, buffer, len))) {
2278 			/* Don't need to canonicalize value */
2279 			rc = err;
2280 			goto out_free;
2281 		}
2282 		memset(buffer, 0, size);
2283 	}
2284 	memcpy(buffer, context, len);
2285 	rc = len;
2286 out_free:
2287 	kfree(context);
2288 out:
2289 	return rc;
2290 }
2291 
2292 static int selinux_inode_setsecurity(struct inode *inode, const char *name,
2293                                      const void *value, size_t size, int flags)
2294 {
2295 	struct inode_security_struct *isec = inode->i_security;
2296 	u32 newsid;
2297 	int rc;
2298 
2299 	if (strcmp(name, XATTR_SELINUX_SUFFIX))
2300 		return -EOPNOTSUPP;
2301 
2302 	if (!value || !size)
2303 		return -EACCES;
2304 
2305 	rc = security_context_to_sid((void*)value, size, &newsid);
2306 	if (rc)
2307 		return rc;
2308 
2309 	isec->sid = newsid;
2310 	return 0;
2311 }
2312 
2313 static int selinux_inode_listsecurity(struct inode *inode, char *buffer, size_t buffer_size)
2314 {
2315 	const int len = sizeof(XATTR_NAME_SELINUX);
2316 	if (buffer && len <= buffer_size)
2317 		memcpy(buffer, XATTR_NAME_SELINUX, len);
2318 	return len;
2319 }
2320 
2321 /* file security operations */
2322 
2323 static int selinux_file_permission(struct file *file, int mask)
2324 {
2325 	struct inode *inode = file->f_dentry->d_inode;
2326 
2327 	if (!mask) {
2328 		/* No permission to check.  Existence test. */
2329 		return 0;
2330 	}
2331 
2332 	/* file_mask_to_av won't add FILE__WRITE if MAY_APPEND is set */
2333 	if ((file->f_flags & O_APPEND) && (mask & MAY_WRITE))
2334 		mask |= MAY_APPEND;
2335 
2336 	return file_has_perm(current, file,
2337 			     file_mask_to_av(inode->i_mode, mask));
2338 }
2339 
2340 static int selinux_file_alloc_security(struct file *file)
2341 {
2342 	return file_alloc_security(file);
2343 }
2344 
2345 static void selinux_file_free_security(struct file *file)
2346 {
2347 	file_free_security(file);
2348 }
2349 
2350 static int selinux_file_ioctl(struct file *file, unsigned int cmd,
2351 			      unsigned long arg)
2352 {
2353 	int error = 0;
2354 
2355 	switch (cmd) {
2356 		case FIONREAD:
2357 		/* fall through */
2358 		case FIBMAP:
2359 		/* fall through */
2360 		case FIGETBSZ:
2361 		/* fall through */
2362 		case EXT2_IOC_GETFLAGS:
2363 		/* fall through */
2364 		case EXT2_IOC_GETVERSION:
2365 			error = file_has_perm(current, file, FILE__GETATTR);
2366 			break;
2367 
2368 		case EXT2_IOC_SETFLAGS:
2369 		/* fall through */
2370 		case EXT2_IOC_SETVERSION:
2371 			error = file_has_perm(current, file, FILE__SETATTR);
2372 			break;
2373 
2374 		/* sys_ioctl() checks */
2375 		case FIONBIO:
2376 		/* fall through */
2377 		case FIOASYNC:
2378 			error = file_has_perm(current, file, 0);
2379 			break;
2380 
2381 	        case KDSKBENT:
2382 	        case KDSKBSENT:
2383 			error = task_has_capability(current,CAP_SYS_TTY_CONFIG);
2384 			break;
2385 
2386 		/* default case assumes that the command will go
2387 		 * to the file's ioctl() function.
2388 		 */
2389 		default:
2390 			error = file_has_perm(current, file, FILE__IOCTL);
2391 
2392 	}
2393 	return error;
2394 }
2395 
2396 static int file_map_prot_check(struct file *file, unsigned long prot, int shared)
2397 {
2398 #ifndef CONFIG_PPC32
2399 	if ((prot & PROT_EXEC) && (!file || (!shared && (prot & PROT_WRITE)))) {
2400 		/*
2401 		 * We are making executable an anonymous mapping or a
2402 		 * private file mapping that will also be writable.
2403 		 * This has an additional check.
2404 		 */
2405 		int rc = task_has_perm(current, current, PROCESS__EXECMEM);
2406 		if (rc)
2407 			return rc;
2408 	}
2409 #endif
2410 
2411 	if (file) {
2412 		/* read access is always possible with a mapping */
2413 		u32 av = FILE__READ;
2414 
2415 		/* write access only matters if the mapping is shared */
2416 		if (shared && (prot & PROT_WRITE))
2417 			av |= FILE__WRITE;
2418 
2419 		if (prot & PROT_EXEC)
2420 			av |= FILE__EXECUTE;
2421 
2422 		return file_has_perm(current, file, av);
2423 	}
2424 	return 0;
2425 }
2426 
2427 static int selinux_file_mmap(struct file *file, unsigned long reqprot,
2428 			     unsigned long prot, unsigned long flags)
2429 {
2430 	int rc;
2431 
2432 	rc = secondary_ops->file_mmap(file, reqprot, prot, flags);
2433 	if (rc)
2434 		return rc;
2435 
2436 	if (selinux_checkreqprot)
2437 		prot = reqprot;
2438 
2439 	return file_map_prot_check(file, prot,
2440 				   (flags & MAP_TYPE) == MAP_SHARED);
2441 }
2442 
2443 static int selinux_file_mprotect(struct vm_area_struct *vma,
2444 				 unsigned long reqprot,
2445 				 unsigned long prot)
2446 {
2447 	int rc;
2448 
2449 	rc = secondary_ops->file_mprotect(vma, reqprot, prot);
2450 	if (rc)
2451 		return rc;
2452 
2453 	if (selinux_checkreqprot)
2454 		prot = reqprot;
2455 
2456 #ifndef CONFIG_PPC32
2457 	if ((prot & PROT_EXEC) && !(vma->vm_flags & VM_EXECUTABLE) &&
2458 	   (vma->vm_start >= vma->vm_mm->start_brk &&
2459 	    vma->vm_end <= vma->vm_mm->brk)) {
2460 	    	/*
2461 		 * We are making an executable mapping in the brk region.
2462 		 * This has an additional execheap check.
2463 		 */
2464 		rc = task_has_perm(current, current, PROCESS__EXECHEAP);
2465 		if (rc)
2466 			return rc;
2467 	}
2468 	if (vma->vm_file != NULL && vma->anon_vma != NULL && (prot & PROT_EXEC)) {
2469 		/*
2470 		 * We are making executable a file mapping that has
2471 		 * had some COW done. Since pages might have been written,
2472 		 * check ability to execute the possibly modified content.
2473 		 * This typically should only occur for text relocations.
2474 		 */
2475 		int rc = file_has_perm(current, vma->vm_file, FILE__EXECMOD);
2476 		if (rc)
2477 			return rc;
2478 	}
2479 	if (!vma->vm_file && (prot & PROT_EXEC) &&
2480 		vma->vm_start <= vma->vm_mm->start_stack &&
2481 		vma->vm_end >= vma->vm_mm->start_stack) {
2482 		/* Attempt to make the process stack executable.
2483 		 * This has an additional execstack check.
2484 		 */
2485 		rc = task_has_perm(current, current, PROCESS__EXECSTACK);
2486 		if (rc)
2487 			return rc;
2488 	}
2489 #endif
2490 
2491 	return file_map_prot_check(vma->vm_file, prot, vma->vm_flags&VM_SHARED);
2492 }
2493 
2494 static int selinux_file_lock(struct file *file, unsigned int cmd)
2495 {
2496 	return file_has_perm(current, file, FILE__LOCK);
2497 }
2498 
2499 static int selinux_file_fcntl(struct file *file, unsigned int cmd,
2500 			      unsigned long arg)
2501 {
2502 	int err = 0;
2503 
2504 	switch (cmd) {
2505 	        case F_SETFL:
2506 			if (!file->f_dentry || !file->f_dentry->d_inode) {
2507 				err = -EINVAL;
2508 				break;
2509 			}
2510 
2511 			if ((file->f_flags & O_APPEND) && !(arg & O_APPEND)) {
2512 				err = file_has_perm(current, file,FILE__WRITE);
2513 				break;
2514 			}
2515 			/* fall through */
2516 	        case F_SETOWN:
2517 	        case F_SETSIG:
2518 	        case F_GETFL:
2519 	        case F_GETOWN:
2520 	        case F_GETSIG:
2521 			/* Just check FD__USE permission */
2522 			err = file_has_perm(current, file, 0);
2523 			break;
2524 		case F_GETLK:
2525 		case F_SETLK:
2526 	        case F_SETLKW:
2527 #if BITS_PER_LONG == 32
2528 	        case F_GETLK64:
2529 		case F_SETLK64:
2530 	        case F_SETLKW64:
2531 #endif
2532 			if (!file->f_dentry || !file->f_dentry->d_inode) {
2533 				err = -EINVAL;
2534 				break;
2535 			}
2536 			err = file_has_perm(current, file, FILE__LOCK);
2537 			break;
2538 	}
2539 
2540 	return err;
2541 }
2542 
2543 static int selinux_file_set_fowner(struct file *file)
2544 {
2545 	struct task_security_struct *tsec;
2546 	struct file_security_struct *fsec;
2547 
2548 	tsec = current->security;
2549 	fsec = file->f_security;
2550 	fsec->fown_sid = tsec->sid;
2551 
2552 	return 0;
2553 }
2554 
2555 static int selinux_file_send_sigiotask(struct task_struct *tsk,
2556 				       struct fown_struct *fown, int signum)
2557 {
2558         struct file *file;
2559 	u32 perm;
2560 	struct task_security_struct *tsec;
2561 	struct file_security_struct *fsec;
2562 
2563 	/* struct fown_struct is never outside the context of a struct file */
2564         file = (struct file *)((long)fown - offsetof(struct file,f_owner));
2565 
2566 	tsec = tsk->security;
2567 	fsec = file->f_security;
2568 
2569 	if (!signum)
2570 		perm = signal_to_av(SIGIO); /* as per send_sigio_to_task */
2571 	else
2572 		perm = signal_to_av(signum);
2573 
2574 	return avc_has_perm(fsec->fown_sid, tsec->sid,
2575 			    SECCLASS_PROCESS, perm, NULL);
2576 }
2577 
2578 static int selinux_file_receive(struct file *file)
2579 {
2580 	return file_has_perm(current, file, file_to_av(file));
2581 }
2582 
2583 /* task security operations */
2584 
2585 static int selinux_task_create(unsigned long clone_flags)
2586 {
2587 	int rc;
2588 
2589 	rc = secondary_ops->task_create(clone_flags);
2590 	if (rc)
2591 		return rc;
2592 
2593 	return task_has_perm(current, current, PROCESS__FORK);
2594 }
2595 
2596 static int selinux_task_alloc_security(struct task_struct *tsk)
2597 {
2598 	struct task_security_struct *tsec1, *tsec2;
2599 	int rc;
2600 
2601 	tsec1 = current->security;
2602 
2603 	rc = task_alloc_security(tsk);
2604 	if (rc)
2605 		return rc;
2606 	tsec2 = tsk->security;
2607 
2608 	tsec2->osid = tsec1->osid;
2609 	tsec2->sid = tsec1->sid;
2610 
2611 	/* Retain the exec and create SIDs across fork */
2612 	tsec2->exec_sid = tsec1->exec_sid;
2613 	tsec2->create_sid = tsec1->create_sid;
2614 
2615 	/* Retain ptracer SID across fork, if any.
2616 	   This will be reset by the ptrace hook upon any
2617 	   subsequent ptrace_attach operations. */
2618 	tsec2->ptrace_sid = tsec1->ptrace_sid;
2619 
2620 	return 0;
2621 }
2622 
2623 static void selinux_task_free_security(struct task_struct *tsk)
2624 {
2625 	task_free_security(tsk);
2626 }
2627 
2628 static int selinux_task_setuid(uid_t id0, uid_t id1, uid_t id2, int flags)
2629 {
2630 	/* Since setuid only affects the current process, and
2631 	   since the SELinux controls are not based on the Linux
2632 	   identity attributes, SELinux does not need to control
2633 	   this operation.  However, SELinux does control the use
2634 	   of the CAP_SETUID and CAP_SETGID capabilities using the
2635 	   capable hook. */
2636 	return 0;
2637 }
2638 
2639 static int selinux_task_post_setuid(uid_t id0, uid_t id1, uid_t id2, int flags)
2640 {
2641 	return secondary_ops->task_post_setuid(id0,id1,id2,flags);
2642 }
2643 
2644 static int selinux_task_setgid(gid_t id0, gid_t id1, gid_t id2, int flags)
2645 {
2646 	/* See the comment for setuid above. */
2647 	return 0;
2648 }
2649 
2650 static int selinux_task_setpgid(struct task_struct *p, pid_t pgid)
2651 {
2652 	return task_has_perm(current, p, PROCESS__SETPGID);
2653 }
2654 
2655 static int selinux_task_getpgid(struct task_struct *p)
2656 {
2657 	return task_has_perm(current, p, PROCESS__GETPGID);
2658 }
2659 
2660 static int selinux_task_getsid(struct task_struct *p)
2661 {
2662 	return task_has_perm(current, p, PROCESS__GETSESSION);
2663 }
2664 
2665 static int selinux_task_setgroups(struct group_info *group_info)
2666 {
2667 	/* See the comment for setuid above. */
2668 	return 0;
2669 }
2670 
2671 static int selinux_task_setnice(struct task_struct *p, int nice)
2672 {
2673 	int rc;
2674 
2675 	rc = secondary_ops->task_setnice(p, nice);
2676 	if (rc)
2677 		return rc;
2678 
2679 	return task_has_perm(current,p, PROCESS__SETSCHED);
2680 }
2681 
2682 static int selinux_task_setrlimit(unsigned int resource, struct rlimit *new_rlim)
2683 {
2684 	struct rlimit *old_rlim = current->signal->rlim + resource;
2685 	int rc;
2686 
2687 	rc = secondary_ops->task_setrlimit(resource, new_rlim);
2688 	if (rc)
2689 		return rc;
2690 
2691 	/* Control the ability to change the hard limit (whether
2692 	   lowering or raising it), so that the hard limit can
2693 	   later be used as a safe reset point for the soft limit
2694 	   upon context transitions. See selinux_bprm_apply_creds. */
2695 	if (old_rlim->rlim_max != new_rlim->rlim_max)
2696 		return task_has_perm(current, current, PROCESS__SETRLIMIT);
2697 
2698 	return 0;
2699 }
2700 
2701 static int selinux_task_setscheduler(struct task_struct *p, int policy, struct sched_param *lp)
2702 {
2703 	return task_has_perm(current, p, PROCESS__SETSCHED);
2704 }
2705 
2706 static int selinux_task_getscheduler(struct task_struct *p)
2707 {
2708 	return task_has_perm(current, p, PROCESS__GETSCHED);
2709 }
2710 
2711 static int selinux_task_kill(struct task_struct *p, struct siginfo *info, int sig)
2712 {
2713 	u32 perm;
2714 	int rc;
2715 
2716 	rc = secondary_ops->task_kill(p, info, sig);
2717 	if (rc)
2718 		return rc;
2719 
2720 	if (info != SEND_SIG_NOINFO && (is_si_special(info) || SI_FROMKERNEL(info)))
2721 		return 0;
2722 
2723 	if (!sig)
2724 		perm = PROCESS__SIGNULL; /* null signal; existence test */
2725 	else
2726 		perm = signal_to_av(sig);
2727 
2728 	return task_has_perm(current, p, perm);
2729 }
2730 
2731 static int selinux_task_prctl(int option,
2732 			      unsigned long arg2,
2733 			      unsigned long arg3,
2734 			      unsigned long arg4,
2735 			      unsigned long arg5)
2736 {
2737 	/* The current prctl operations do not appear to require
2738 	   any SELinux controls since they merely observe or modify
2739 	   the state of the current process. */
2740 	return 0;
2741 }
2742 
2743 static int selinux_task_wait(struct task_struct *p)
2744 {
2745 	u32 perm;
2746 
2747 	perm = signal_to_av(p->exit_signal);
2748 
2749 	return task_has_perm(p, current, perm);
2750 }
2751 
2752 static void selinux_task_reparent_to_init(struct task_struct *p)
2753 {
2754   	struct task_security_struct *tsec;
2755 
2756 	secondary_ops->task_reparent_to_init(p);
2757 
2758 	tsec = p->security;
2759 	tsec->osid = tsec->sid;
2760 	tsec->sid = SECINITSID_KERNEL;
2761 	return;
2762 }
2763 
2764 static void selinux_task_to_inode(struct task_struct *p,
2765 				  struct inode *inode)
2766 {
2767 	struct task_security_struct *tsec = p->security;
2768 	struct inode_security_struct *isec = inode->i_security;
2769 
2770 	isec->sid = tsec->sid;
2771 	isec->initialized = 1;
2772 	return;
2773 }
2774 
2775 #ifdef CONFIG_SECURITY_NETWORK
2776 
2777 /* Returns error only if unable to parse addresses */
2778 static int selinux_parse_skb_ipv4(struct sk_buff *skb, struct avc_audit_data *ad)
2779 {
2780 	int offset, ihlen, ret = -EINVAL;
2781 	struct iphdr _iph, *ih;
2782 
2783 	offset = skb->nh.raw - skb->data;
2784 	ih = skb_header_pointer(skb, offset, sizeof(_iph), &_iph);
2785 	if (ih == NULL)
2786 		goto out;
2787 
2788 	ihlen = ih->ihl * 4;
2789 	if (ihlen < sizeof(_iph))
2790 		goto out;
2791 
2792 	ad->u.net.v4info.saddr = ih->saddr;
2793 	ad->u.net.v4info.daddr = ih->daddr;
2794 	ret = 0;
2795 
2796 	switch (ih->protocol) {
2797         case IPPROTO_TCP: {
2798         	struct tcphdr _tcph, *th;
2799 
2800         	if (ntohs(ih->frag_off) & IP_OFFSET)
2801         		break;
2802 
2803 		offset += ihlen;
2804 		th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph);
2805 		if (th == NULL)
2806 			break;
2807 
2808 		ad->u.net.sport = th->source;
2809 		ad->u.net.dport = th->dest;
2810 		break;
2811         }
2812 
2813         case IPPROTO_UDP: {
2814         	struct udphdr _udph, *uh;
2815 
2816         	if (ntohs(ih->frag_off) & IP_OFFSET)
2817         		break;
2818 
2819 		offset += ihlen;
2820         	uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph);
2821 		if (uh == NULL)
2822 			break;
2823 
2824         	ad->u.net.sport = uh->source;
2825         	ad->u.net.dport = uh->dest;
2826         	break;
2827         }
2828 
2829         default:
2830         	break;
2831         }
2832 out:
2833 	return ret;
2834 }
2835 
2836 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
2837 
2838 /* Returns error only if unable to parse addresses */
2839 static int selinux_parse_skb_ipv6(struct sk_buff *skb, struct avc_audit_data *ad)
2840 {
2841 	u8 nexthdr;
2842 	int ret = -EINVAL, offset;
2843 	struct ipv6hdr _ipv6h, *ip6;
2844 
2845 	offset = skb->nh.raw - skb->data;
2846 	ip6 = skb_header_pointer(skb, offset, sizeof(_ipv6h), &_ipv6h);
2847 	if (ip6 == NULL)
2848 		goto out;
2849 
2850 	ipv6_addr_copy(&ad->u.net.v6info.saddr, &ip6->saddr);
2851 	ipv6_addr_copy(&ad->u.net.v6info.daddr, &ip6->daddr);
2852 	ret = 0;
2853 
2854 	nexthdr = ip6->nexthdr;
2855 	offset += sizeof(_ipv6h);
2856 	offset = ipv6_skip_exthdr(skb, offset, &nexthdr);
2857 	if (offset < 0)
2858 		goto out;
2859 
2860 	switch (nexthdr) {
2861 	case IPPROTO_TCP: {
2862         	struct tcphdr _tcph, *th;
2863 
2864 		th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph);
2865 		if (th == NULL)
2866 			break;
2867 
2868 		ad->u.net.sport = th->source;
2869 		ad->u.net.dport = th->dest;
2870 		break;
2871 	}
2872 
2873 	case IPPROTO_UDP: {
2874 		struct udphdr _udph, *uh;
2875 
2876 		uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph);
2877 		if (uh == NULL)
2878 			break;
2879 
2880 		ad->u.net.sport = uh->source;
2881 		ad->u.net.dport = uh->dest;
2882 		break;
2883 	}
2884 
2885 	/* includes fragments */
2886 	default:
2887 		break;
2888 	}
2889 out:
2890 	return ret;
2891 }
2892 
2893 #endif /* IPV6 */
2894 
2895 static int selinux_parse_skb(struct sk_buff *skb, struct avc_audit_data *ad,
2896 			     char **addrp, int *len, int src)
2897 {
2898 	int ret = 0;
2899 
2900 	switch (ad->u.net.family) {
2901 	case PF_INET:
2902 		ret = selinux_parse_skb_ipv4(skb, ad);
2903 		if (ret || !addrp)
2904 			break;
2905 		*len = 4;
2906 		*addrp = (char *)(src ? &ad->u.net.v4info.saddr :
2907 					&ad->u.net.v4info.daddr);
2908 		break;
2909 
2910 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
2911 	case PF_INET6:
2912 		ret = selinux_parse_skb_ipv6(skb, ad);
2913 		if (ret || !addrp)
2914 			break;
2915 		*len = 16;
2916 		*addrp = (char *)(src ? &ad->u.net.v6info.saddr :
2917 					&ad->u.net.v6info.daddr);
2918 		break;
2919 #endif	/* IPV6 */
2920 	default:
2921 		break;
2922 	}
2923 
2924 	return ret;
2925 }
2926 
2927 /* socket security operations */
2928 static int socket_has_perm(struct task_struct *task, struct socket *sock,
2929 			   u32 perms)
2930 {
2931 	struct inode_security_struct *isec;
2932 	struct task_security_struct *tsec;
2933 	struct avc_audit_data ad;
2934 	int err = 0;
2935 
2936 	tsec = task->security;
2937 	isec = SOCK_INODE(sock)->i_security;
2938 
2939 	if (isec->sid == SECINITSID_KERNEL)
2940 		goto out;
2941 
2942 	AVC_AUDIT_DATA_INIT(&ad,NET);
2943 	ad.u.net.sk = sock->sk;
2944 	err = avc_has_perm(tsec->sid, isec->sid, isec->sclass, perms, &ad);
2945 
2946 out:
2947 	return err;
2948 }
2949 
2950 static int selinux_socket_create(int family, int type,
2951 				 int protocol, int kern)
2952 {
2953 	int err = 0;
2954 	struct task_security_struct *tsec;
2955 
2956 	if (kern)
2957 		goto out;
2958 
2959 	tsec = current->security;
2960 	err = avc_has_perm(tsec->sid, tsec->sid,
2961 			   socket_type_to_security_class(family, type,
2962 			   protocol), SOCKET__CREATE, NULL);
2963 
2964 out:
2965 	return err;
2966 }
2967 
2968 static void selinux_socket_post_create(struct socket *sock, int family,
2969 				       int type, int protocol, int kern)
2970 {
2971 	struct inode_security_struct *isec;
2972 	struct task_security_struct *tsec;
2973 
2974 	isec = SOCK_INODE(sock)->i_security;
2975 
2976 	tsec = current->security;
2977 	isec->sclass = socket_type_to_security_class(family, type, protocol);
2978 	isec->sid = kern ? SECINITSID_KERNEL : tsec->sid;
2979 	isec->initialized = 1;
2980 
2981 	return;
2982 }
2983 
2984 /* Range of port numbers used to automatically bind.
2985    Need to determine whether we should perform a name_bind
2986    permission check between the socket and the port number. */
2987 #define ip_local_port_range_0 sysctl_local_port_range[0]
2988 #define ip_local_port_range_1 sysctl_local_port_range[1]
2989 
2990 static int selinux_socket_bind(struct socket *sock, struct sockaddr *address, int addrlen)
2991 {
2992 	u16 family;
2993 	int err;
2994 
2995 	err = socket_has_perm(current, sock, SOCKET__BIND);
2996 	if (err)
2997 		goto out;
2998 
2999 	/*
3000 	 * If PF_INET or PF_INET6, check name_bind permission for the port.
3001 	 * Multiple address binding for SCTP is not supported yet: we just
3002 	 * check the first address now.
3003 	 */
3004 	family = sock->sk->sk_family;
3005 	if (family == PF_INET || family == PF_INET6) {
3006 		char *addrp;
3007 		struct inode_security_struct *isec;
3008 		struct task_security_struct *tsec;
3009 		struct avc_audit_data ad;
3010 		struct sockaddr_in *addr4 = NULL;
3011 		struct sockaddr_in6 *addr6 = NULL;
3012 		unsigned short snum;
3013 		struct sock *sk = sock->sk;
3014 		u32 sid, node_perm, addrlen;
3015 
3016 		tsec = current->security;
3017 		isec = SOCK_INODE(sock)->i_security;
3018 
3019 		if (family == PF_INET) {
3020 			addr4 = (struct sockaddr_in *)address;
3021 			snum = ntohs(addr4->sin_port);
3022 			addrlen = sizeof(addr4->sin_addr.s_addr);
3023 			addrp = (char *)&addr4->sin_addr.s_addr;
3024 		} else {
3025 			addr6 = (struct sockaddr_in6 *)address;
3026 			snum = ntohs(addr6->sin6_port);
3027 			addrlen = sizeof(addr6->sin6_addr.s6_addr);
3028 			addrp = (char *)&addr6->sin6_addr.s6_addr;
3029 		}
3030 
3031 		if (snum&&(snum < max(PROT_SOCK,ip_local_port_range_0) ||
3032 			   snum > ip_local_port_range_1)) {
3033 			err = security_port_sid(sk->sk_family, sk->sk_type,
3034 						sk->sk_protocol, snum, &sid);
3035 			if (err)
3036 				goto out;
3037 			AVC_AUDIT_DATA_INIT(&ad,NET);
3038 			ad.u.net.sport = htons(snum);
3039 			ad.u.net.family = family;
3040 			err = avc_has_perm(isec->sid, sid,
3041 					   isec->sclass,
3042 					   SOCKET__NAME_BIND, &ad);
3043 			if (err)
3044 				goto out;
3045 		}
3046 
3047 		switch(isec->sclass) {
3048 		case SECCLASS_TCP_SOCKET:
3049 			node_perm = TCP_SOCKET__NODE_BIND;
3050 			break;
3051 
3052 		case SECCLASS_UDP_SOCKET:
3053 			node_perm = UDP_SOCKET__NODE_BIND;
3054 			break;
3055 
3056 		default:
3057 			node_perm = RAWIP_SOCKET__NODE_BIND;
3058 			break;
3059 		}
3060 
3061 		err = security_node_sid(family, addrp, addrlen, &sid);
3062 		if (err)
3063 			goto out;
3064 
3065 		AVC_AUDIT_DATA_INIT(&ad,NET);
3066 		ad.u.net.sport = htons(snum);
3067 		ad.u.net.family = family;
3068 
3069 		if (family == PF_INET)
3070 			ad.u.net.v4info.saddr = addr4->sin_addr.s_addr;
3071 		else
3072 			ipv6_addr_copy(&ad.u.net.v6info.saddr, &addr6->sin6_addr);
3073 
3074 		err = avc_has_perm(isec->sid, sid,
3075 		                   isec->sclass, node_perm, &ad);
3076 		if (err)
3077 			goto out;
3078 	}
3079 out:
3080 	return err;
3081 }
3082 
3083 static int selinux_socket_connect(struct socket *sock, struct sockaddr *address, int addrlen)
3084 {
3085 	struct inode_security_struct *isec;
3086 	int err;
3087 
3088 	err = socket_has_perm(current, sock, SOCKET__CONNECT);
3089 	if (err)
3090 		return err;
3091 
3092 	/*
3093 	 * If a TCP socket, check name_connect permission for the port.
3094 	 */
3095 	isec = SOCK_INODE(sock)->i_security;
3096 	if (isec->sclass == SECCLASS_TCP_SOCKET) {
3097 		struct sock *sk = sock->sk;
3098 		struct avc_audit_data ad;
3099 		struct sockaddr_in *addr4 = NULL;
3100 		struct sockaddr_in6 *addr6 = NULL;
3101 		unsigned short snum;
3102 		u32 sid;
3103 
3104 		if (sk->sk_family == PF_INET) {
3105 			addr4 = (struct sockaddr_in *)address;
3106 			if (addrlen < sizeof(struct sockaddr_in))
3107 				return -EINVAL;
3108 			snum = ntohs(addr4->sin_port);
3109 		} else {
3110 			addr6 = (struct sockaddr_in6 *)address;
3111 			if (addrlen < SIN6_LEN_RFC2133)
3112 				return -EINVAL;
3113 			snum = ntohs(addr6->sin6_port);
3114 		}
3115 
3116 		err = security_port_sid(sk->sk_family, sk->sk_type,
3117 					sk->sk_protocol, snum, &sid);
3118 		if (err)
3119 			goto out;
3120 
3121 		AVC_AUDIT_DATA_INIT(&ad,NET);
3122 		ad.u.net.dport = htons(snum);
3123 		ad.u.net.family = sk->sk_family;
3124 		err = avc_has_perm(isec->sid, sid, isec->sclass,
3125 				   TCP_SOCKET__NAME_CONNECT, &ad);
3126 		if (err)
3127 			goto out;
3128 	}
3129 
3130 out:
3131 	return err;
3132 }
3133 
3134 static int selinux_socket_listen(struct socket *sock, int backlog)
3135 {
3136 	return socket_has_perm(current, sock, SOCKET__LISTEN);
3137 }
3138 
3139 static int selinux_socket_accept(struct socket *sock, struct socket *newsock)
3140 {
3141 	int err;
3142 	struct inode_security_struct *isec;
3143 	struct inode_security_struct *newisec;
3144 
3145 	err = socket_has_perm(current, sock, SOCKET__ACCEPT);
3146 	if (err)
3147 		return err;
3148 
3149 	newisec = SOCK_INODE(newsock)->i_security;
3150 
3151 	isec = SOCK_INODE(sock)->i_security;
3152 	newisec->sclass = isec->sclass;
3153 	newisec->sid = isec->sid;
3154 	newisec->initialized = 1;
3155 
3156 	return 0;
3157 }
3158 
3159 static int selinux_socket_sendmsg(struct socket *sock, struct msghdr *msg,
3160  				  int size)
3161 {
3162 	return socket_has_perm(current, sock, SOCKET__WRITE);
3163 }
3164 
3165 static int selinux_socket_recvmsg(struct socket *sock, struct msghdr *msg,
3166 				  int size, int flags)
3167 {
3168 	return socket_has_perm(current, sock, SOCKET__READ);
3169 }
3170 
3171 static int selinux_socket_getsockname(struct socket *sock)
3172 {
3173 	return socket_has_perm(current, sock, SOCKET__GETATTR);
3174 }
3175 
3176 static int selinux_socket_getpeername(struct socket *sock)
3177 {
3178 	return socket_has_perm(current, sock, SOCKET__GETATTR);
3179 }
3180 
3181 static int selinux_socket_setsockopt(struct socket *sock,int level,int optname)
3182 {
3183 	return socket_has_perm(current, sock, SOCKET__SETOPT);
3184 }
3185 
3186 static int selinux_socket_getsockopt(struct socket *sock, int level,
3187 				     int optname)
3188 {
3189 	return socket_has_perm(current, sock, SOCKET__GETOPT);
3190 }
3191 
3192 static int selinux_socket_shutdown(struct socket *sock, int how)
3193 {
3194 	return socket_has_perm(current, sock, SOCKET__SHUTDOWN);
3195 }
3196 
3197 static int selinux_socket_unix_stream_connect(struct socket *sock,
3198 					      struct socket *other,
3199 					      struct sock *newsk)
3200 {
3201 	struct sk_security_struct *ssec;
3202 	struct inode_security_struct *isec;
3203 	struct inode_security_struct *other_isec;
3204 	struct avc_audit_data ad;
3205 	int err;
3206 
3207 	err = secondary_ops->unix_stream_connect(sock, other, newsk);
3208 	if (err)
3209 		return err;
3210 
3211 	isec = SOCK_INODE(sock)->i_security;
3212 	other_isec = SOCK_INODE(other)->i_security;
3213 
3214 	AVC_AUDIT_DATA_INIT(&ad,NET);
3215 	ad.u.net.sk = other->sk;
3216 
3217 	err = avc_has_perm(isec->sid, other_isec->sid,
3218 			   isec->sclass,
3219 			   UNIX_STREAM_SOCKET__CONNECTTO, &ad);
3220 	if (err)
3221 		return err;
3222 
3223 	/* connecting socket */
3224 	ssec = sock->sk->sk_security;
3225 	ssec->peer_sid = other_isec->sid;
3226 
3227 	/* server child socket */
3228 	ssec = newsk->sk_security;
3229 	ssec->peer_sid = isec->sid;
3230 
3231 	return 0;
3232 }
3233 
3234 static int selinux_socket_unix_may_send(struct socket *sock,
3235 					struct socket *other)
3236 {
3237 	struct inode_security_struct *isec;
3238 	struct inode_security_struct *other_isec;
3239 	struct avc_audit_data ad;
3240 	int err;
3241 
3242 	isec = SOCK_INODE(sock)->i_security;
3243 	other_isec = SOCK_INODE(other)->i_security;
3244 
3245 	AVC_AUDIT_DATA_INIT(&ad,NET);
3246 	ad.u.net.sk = other->sk;
3247 
3248 	err = avc_has_perm(isec->sid, other_isec->sid,
3249 			   isec->sclass, SOCKET__SENDTO, &ad);
3250 	if (err)
3251 		return err;
3252 
3253 	return 0;
3254 }
3255 
3256 static int selinux_socket_sock_rcv_skb(struct sock *sk, struct sk_buff *skb)
3257 {
3258 	u16 family;
3259 	char *addrp;
3260 	int len, err = 0;
3261 	u32 netif_perm, node_perm, node_sid, if_sid, recv_perm = 0;
3262 	u32 sock_sid = 0;
3263 	u16 sock_class = 0;
3264 	struct socket *sock;
3265 	struct net_device *dev;
3266 	struct avc_audit_data ad;
3267 
3268 	family = sk->sk_family;
3269 	if (family != PF_INET && family != PF_INET6)
3270 		goto out;
3271 
3272 	/* Handle mapped IPv4 packets arriving via IPv6 sockets */
3273 	if (family == PF_INET6 && skb->protocol == ntohs(ETH_P_IP))
3274 		family = PF_INET;
3275 
3276  	read_lock_bh(&sk->sk_callback_lock);
3277  	sock = sk->sk_socket;
3278  	if (sock) {
3279  		struct inode *inode;
3280  		inode = SOCK_INODE(sock);
3281  		if (inode) {
3282  			struct inode_security_struct *isec;
3283  			isec = inode->i_security;
3284  			sock_sid = isec->sid;
3285  			sock_class = isec->sclass;
3286  		}
3287  	}
3288  	read_unlock_bh(&sk->sk_callback_lock);
3289  	if (!sock_sid)
3290   		goto out;
3291 
3292 	dev = skb->dev;
3293 	if (!dev)
3294 		goto out;
3295 
3296 	err = sel_netif_sids(dev, &if_sid, NULL);
3297 	if (err)
3298 		goto out;
3299 
3300 	switch (sock_class) {
3301 	case SECCLASS_UDP_SOCKET:
3302 		netif_perm = NETIF__UDP_RECV;
3303 		node_perm = NODE__UDP_RECV;
3304 		recv_perm = UDP_SOCKET__RECV_MSG;
3305 		break;
3306 
3307 	case SECCLASS_TCP_SOCKET:
3308 		netif_perm = NETIF__TCP_RECV;
3309 		node_perm = NODE__TCP_RECV;
3310 		recv_perm = TCP_SOCKET__RECV_MSG;
3311 		break;
3312 
3313 	default:
3314 		netif_perm = NETIF__RAWIP_RECV;
3315 		node_perm = NODE__RAWIP_RECV;
3316 		break;
3317 	}
3318 
3319 	AVC_AUDIT_DATA_INIT(&ad, NET);
3320 	ad.u.net.netif = dev->name;
3321 	ad.u.net.family = family;
3322 
3323 	err = selinux_parse_skb(skb, &ad, &addrp, &len, 1);
3324 	if (err)
3325 		goto out;
3326 
3327 	err = avc_has_perm(sock_sid, if_sid, SECCLASS_NETIF, netif_perm, &ad);
3328 	if (err)
3329 		goto out;
3330 
3331 	/* Fixme: this lookup is inefficient */
3332 	err = security_node_sid(family, addrp, len, &node_sid);
3333 	if (err)
3334 		goto out;
3335 
3336 	err = avc_has_perm(sock_sid, node_sid, SECCLASS_NODE, node_perm, &ad);
3337 	if (err)
3338 		goto out;
3339 
3340 	if (recv_perm) {
3341 		u32 port_sid;
3342 
3343 		/* Fixme: make this more efficient */
3344 		err = security_port_sid(sk->sk_family, sk->sk_type,
3345 		                        sk->sk_protocol, ntohs(ad.u.net.sport),
3346 		                        &port_sid);
3347 		if (err)
3348 			goto out;
3349 
3350 		err = avc_has_perm(sock_sid, port_sid,
3351 				   sock_class, recv_perm, &ad);
3352 	}
3353 
3354 	if (!err)
3355 		err = selinux_xfrm_sock_rcv_skb(sock_sid, skb);
3356 
3357 out:
3358 	return err;
3359 }
3360 
3361 static int selinux_socket_getpeersec(struct socket *sock, char __user *optval,
3362 				     int __user *optlen, unsigned len)
3363 {
3364 	int err = 0;
3365 	char *scontext;
3366 	u32 scontext_len;
3367 	struct sk_security_struct *ssec;
3368 	struct inode_security_struct *isec;
3369 
3370 	isec = SOCK_INODE(sock)->i_security;
3371 	if (isec->sclass != SECCLASS_UNIX_STREAM_SOCKET) {
3372 		err = -ENOPROTOOPT;
3373 		goto out;
3374 	}
3375 
3376 	ssec = sock->sk->sk_security;
3377 
3378 	err = security_sid_to_context(ssec->peer_sid, &scontext, &scontext_len);
3379 	if (err)
3380 		goto out;
3381 
3382 	if (scontext_len > len) {
3383 		err = -ERANGE;
3384 		goto out_len;
3385 	}
3386 
3387 	if (copy_to_user(optval, scontext, scontext_len))
3388 		err = -EFAULT;
3389 
3390 out_len:
3391 	if (put_user(scontext_len, optlen))
3392 		err = -EFAULT;
3393 
3394 	kfree(scontext);
3395 out:
3396 	return err;
3397 }
3398 
3399 static int selinux_sk_alloc_security(struct sock *sk, int family, gfp_t priority)
3400 {
3401 	return sk_alloc_security(sk, family, priority);
3402 }
3403 
3404 static void selinux_sk_free_security(struct sock *sk)
3405 {
3406 	sk_free_security(sk);
3407 }
3408 
3409 static unsigned int selinux_sk_getsid_security(struct sock *sk, struct flowi *fl, u8 dir)
3410 {
3411 	struct inode_security_struct *isec;
3412 	u32 sock_sid = SECINITSID_ANY_SOCKET;
3413 
3414 	if (!sk)
3415 		return selinux_no_sk_sid(fl);
3416 
3417 	read_lock_bh(&sk->sk_callback_lock);
3418 	isec = get_sock_isec(sk);
3419 
3420 	if (isec)
3421 		sock_sid = isec->sid;
3422 
3423 	read_unlock_bh(&sk->sk_callback_lock);
3424 	return sock_sid;
3425 }
3426 
3427 static int selinux_nlmsg_perm(struct sock *sk, struct sk_buff *skb)
3428 {
3429 	int err = 0;
3430 	u32 perm;
3431 	struct nlmsghdr *nlh;
3432 	struct socket *sock = sk->sk_socket;
3433 	struct inode_security_struct *isec = SOCK_INODE(sock)->i_security;
3434 
3435 	if (skb->len < NLMSG_SPACE(0)) {
3436 		err = -EINVAL;
3437 		goto out;
3438 	}
3439 	nlh = (struct nlmsghdr *)skb->data;
3440 
3441 	err = selinux_nlmsg_lookup(isec->sclass, nlh->nlmsg_type, &perm);
3442 	if (err) {
3443 		if (err == -EINVAL) {
3444 			audit_log(current->audit_context, GFP_KERNEL, AUDIT_SELINUX_ERR,
3445 				  "SELinux:  unrecognized netlink message"
3446 				  " type=%hu for sclass=%hu\n",
3447 				  nlh->nlmsg_type, isec->sclass);
3448 			if (!selinux_enforcing)
3449 				err = 0;
3450 		}
3451 
3452 		/* Ignore */
3453 		if (err == -ENOENT)
3454 			err = 0;
3455 		goto out;
3456 	}
3457 
3458 	err = socket_has_perm(current, sock, perm);
3459 out:
3460 	return err;
3461 }
3462 
3463 #ifdef CONFIG_NETFILTER
3464 
3465 static unsigned int selinux_ip_postroute_last(unsigned int hooknum,
3466                                               struct sk_buff **pskb,
3467                                               const struct net_device *in,
3468                                               const struct net_device *out,
3469                                               int (*okfn)(struct sk_buff *),
3470                                               u16 family)
3471 {
3472 	char *addrp;
3473 	int len, err = NF_ACCEPT;
3474 	u32 netif_perm, node_perm, node_sid, if_sid, send_perm = 0;
3475 	struct sock *sk;
3476 	struct socket *sock;
3477 	struct inode *inode;
3478 	struct sk_buff *skb = *pskb;
3479 	struct inode_security_struct *isec;
3480 	struct avc_audit_data ad;
3481 	struct net_device *dev = (struct net_device *)out;
3482 
3483 	sk = skb->sk;
3484 	if (!sk)
3485 		goto out;
3486 
3487 	sock = sk->sk_socket;
3488 	if (!sock)
3489 		goto out;
3490 
3491 	inode = SOCK_INODE(sock);
3492 	if (!inode)
3493 		goto out;
3494 
3495 	err = sel_netif_sids(dev, &if_sid, NULL);
3496 	if (err)
3497 		goto out;
3498 
3499 	isec = inode->i_security;
3500 
3501 	switch (isec->sclass) {
3502 	case SECCLASS_UDP_SOCKET:
3503 		netif_perm = NETIF__UDP_SEND;
3504 		node_perm = NODE__UDP_SEND;
3505 		send_perm = UDP_SOCKET__SEND_MSG;
3506 		break;
3507 
3508 	case SECCLASS_TCP_SOCKET:
3509 		netif_perm = NETIF__TCP_SEND;
3510 		node_perm = NODE__TCP_SEND;
3511 		send_perm = TCP_SOCKET__SEND_MSG;
3512 		break;
3513 
3514 	default:
3515 		netif_perm = NETIF__RAWIP_SEND;
3516 		node_perm = NODE__RAWIP_SEND;
3517 		break;
3518 	}
3519 
3520 
3521 	AVC_AUDIT_DATA_INIT(&ad, NET);
3522 	ad.u.net.netif = dev->name;
3523 	ad.u.net.family = family;
3524 
3525 	err = selinux_parse_skb(skb, &ad, &addrp,
3526 				&len, 0) ? NF_DROP : NF_ACCEPT;
3527 	if (err != NF_ACCEPT)
3528 		goto out;
3529 
3530 	err = avc_has_perm(isec->sid, if_sid, SECCLASS_NETIF,
3531 	                   netif_perm, &ad) ? NF_DROP : NF_ACCEPT;
3532 	if (err != NF_ACCEPT)
3533 		goto out;
3534 
3535 	/* Fixme: this lookup is inefficient */
3536 	err = security_node_sid(family, addrp, len,
3537 				&node_sid) ? NF_DROP : NF_ACCEPT;
3538 	if (err != NF_ACCEPT)
3539 		goto out;
3540 
3541 	err = avc_has_perm(isec->sid, node_sid, SECCLASS_NODE,
3542 	                   node_perm, &ad) ? NF_DROP : NF_ACCEPT;
3543 	if (err != NF_ACCEPT)
3544 		goto out;
3545 
3546 	if (send_perm) {
3547 		u32 port_sid;
3548 
3549 		/* Fixme: make this more efficient */
3550 		err = security_port_sid(sk->sk_family,
3551 		                        sk->sk_type,
3552 		                        sk->sk_protocol,
3553 		                        ntohs(ad.u.net.dport),
3554 		                        &port_sid) ? NF_DROP : NF_ACCEPT;
3555 		if (err != NF_ACCEPT)
3556 			goto out;
3557 
3558 		err = avc_has_perm(isec->sid, port_sid, isec->sclass,
3559 		                   send_perm, &ad) ? NF_DROP : NF_ACCEPT;
3560 	}
3561 
3562 	if (err != NF_ACCEPT)
3563 		goto out;
3564 
3565 	err = selinux_xfrm_postroute_last(isec->sid, skb);
3566 
3567 out:
3568 	return err;
3569 }
3570 
3571 static unsigned int selinux_ipv4_postroute_last(unsigned int hooknum,
3572 						struct sk_buff **pskb,
3573 						const struct net_device *in,
3574 						const struct net_device *out,
3575 						int (*okfn)(struct sk_buff *))
3576 {
3577 	return selinux_ip_postroute_last(hooknum, pskb, in, out, okfn, PF_INET);
3578 }
3579 
3580 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
3581 
3582 static unsigned int selinux_ipv6_postroute_last(unsigned int hooknum,
3583 						struct sk_buff **pskb,
3584 						const struct net_device *in,
3585 						const struct net_device *out,
3586 						int (*okfn)(struct sk_buff *))
3587 {
3588 	return selinux_ip_postroute_last(hooknum, pskb, in, out, okfn, PF_INET6);
3589 }
3590 
3591 #endif	/* IPV6 */
3592 
3593 #endif	/* CONFIG_NETFILTER */
3594 
3595 #else
3596 
3597 static inline int selinux_nlmsg_perm(struct sock *sk, struct sk_buff *skb)
3598 {
3599 	return 0;
3600 }
3601 
3602 #endif	/* CONFIG_SECURITY_NETWORK */
3603 
3604 static int selinux_netlink_send(struct sock *sk, struct sk_buff *skb)
3605 {
3606 	struct task_security_struct *tsec;
3607 	struct av_decision avd;
3608 	int err;
3609 
3610 	err = secondary_ops->netlink_send(sk, skb);
3611 	if (err)
3612 		return err;
3613 
3614 	tsec = current->security;
3615 
3616 	avd.allowed = 0;
3617 	avc_has_perm_noaudit(tsec->sid, tsec->sid,
3618 				SECCLASS_CAPABILITY, ~0, &avd);
3619 	cap_mask(NETLINK_CB(skb).eff_cap, avd.allowed);
3620 
3621 	if (policydb_loaded_version >= POLICYDB_VERSION_NLCLASS)
3622 		err = selinux_nlmsg_perm(sk, skb);
3623 
3624 	return err;
3625 }
3626 
3627 static int selinux_netlink_recv(struct sk_buff *skb)
3628 {
3629 	if (!cap_raised(NETLINK_CB(skb).eff_cap, CAP_NET_ADMIN))
3630 		return -EPERM;
3631 	return 0;
3632 }
3633 
3634 static int ipc_alloc_security(struct task_struct *task,
3635 			      struct kern_ipc_perm *perm,
3636 			      u16 sclass)
3637 {
3638 	struct task_security_struct *tsec = task->security;
3639 	struct ipc_security_struct *isec;
3640 
3641 	isec = kzalloc(sizeof(struct ipc_security_struct), GFP_KERNEL);
3642 	if (!isec)
3643 		return -ENOMEM;
3644 
3645 	isec->magic = SELINUX_MAGIC;
3646 	isec->sclass = sclass;
3647 	isec->ipc_perm = perm;
3648 	if (tsec) {
3649 		isec->sid = tsec->sid;
3650 	} else {
3651 		isec->sid = SECINITSID_UNLABELED;
3652 	}
3653 	perm->security = isec;
3654 
3655 	return 0;
3656 }
3657 
3658 static void ipc_free_security(struct kern_ipc_perm *perm)
3659 {
3660 	struct ipc_security_struct *isec = perm->security;
3661 	if (!isec || isec->magic != SELINUX_MAGIC)
3662 		return;
3663 
3664 	perm->security = NULL;
3665 	kfree(isec);
3666 }
3667 
3668 static int msg_msg_alloc_security(struct msg_msg *msg)
3669 {
3670 	struct msg_security_struct *msec;
3671 
3672 	msec = kzalloc(sizeof(struct msg_security_struct), GFP_KERNEL);
3673 	if (!msec)
3674 		return -ENOMEM;
3675 
3676 	msec->magic = SELINUX_MAGIC;
3677 	msec->msg = msg;
3678 	msec->sid = SECINITSID_UNLABELED;
3679 	msg->security = msec;
3680 
3681 	return 0;
3682 }
3683 
3684 static void msg_msg_free_security(struct msg_msg *msg)
3685 {
3686 	struct msg_security_struct *msec = msg->security;
3687 	if (!msec || msec->magic != SELINUX_MAGIC)
3688 		return;
3689 
3690 	msg->security = NULL;
3691 	kfree(msec);
3692 }
3693 
3694 static int ipc_has_perm(struct kern_ipc_perm *ipc_perms,
3695 			u32 perms)
3696 {
3697 	struct task_security_struct *tsec;
3698 	struct ipc_security_struct *isec;
3699 	struct avc_audit_data ad;
3700 
3701 	tsec = current->security;
3702 	isec = ipc_perms->security;
3703 
3704 	AVC_AUDIT_DATA_INIT(&ad, IPC);
3705 	ad.u.ipc_id = ipc_perms->key;
3706 
3707 	return avc_has_perm(tsec->sid, isec->sid, isec->sclass, perms, &ad);
3708 }
3709 
3710 static int selinux_msg_msg_alloc_security(struct msg_msg *msg)
3711 {
3712 	return msg_msg_alloc_security(msg);
3713 }
3714 
3715 static void selinux_msg_msg_free_security(struct msg_msg *msg)
3716 {
3717 	msg_msg_free_security(msg);
3718 }
3719 
3720 /* message queue security operations */
3721 static int selinux_msg_queue_alloc_security(struct msg_queue *msq)
3722 {
3723 	struct task_security_struct *tsec;
3724 	struct ipc_security_struct *isec;
3725 	struct avc_audit_data ad;
3726 	int rc;
3727 
3728 	rc = ipc_alloc_security(current, &msq->q_perm, SECCLASS_MSGQ);
3729 	if (rc)
3730 		return rc;
3731 
3732 	tsec = current->security;
3733 	isec = msq->q_perm.security;
3734 
3735 	AVC_AUDIT_DATA_INIT(&ad, IPC);
3736  	ad.u.ipc_id = msq->q_perm.key;
3737 
3738 	rc = avc_has_perm(tsec->sid, isec->sid, SECCLASS_MSGQ,
3739 			  MSGQ__CREATE, &ad);
3740 	if (rc) {
3741 		ipc_free_security(&msq->q_perm);
3742 		return rc;
3743 	}
3744 	return 0;
3745 }
3746 
3747 static void selinux_msg_queue_free_security(struct msg_queue *msq)
3748 {
3749 	ipc_free_security(&msq->q_perm);
3750 }
3751 
3752 static int selinux_msg_queue_associate(struct msg_queue *msq, int msqflg)
3753 {
3754 	struct task_security_struct *tsec;
3755 	struct ipc_security_struct *isec;
3756 	struct avc_audit_data ad;
3757 
3758 	tsec = current->security;
3759 	isec = msq->q_perm.security;
3760 
3761 	AVC_AUDIT_DATA_INIT(&ad, IPC);
3762 	ad.u.ipc_id = msq->q_perm.key;
3763 
3764 	return avc_has_perm(tsec->sid, isec->sid, SECCLASS_MSGQ,
3765 			    MSGQ__ASSOCIATE, &ad);
3766 }
3767 
3768 static int selinux_msg_queue_msgctl(struct msg_queue *msq, int cmd)
3769 {
3770 	int err;
3771 	int perms;
3772 
3773 	switch(cmd) {
3774 	case IPC_INFO:
3775 	case MSG_INFO:
3776 		/* No specific object, just general system-wide information. */
3777 		return task_has_system(current, SYSTEM__IPC_INFO);
3778 	case IPC_STAT:
3779 	case MSG_STAT:
3780 		perms = MSGQ__GETATTR | MSGQ__ASSOCIATE;
3781 		break;
3782 	case IPC_SET:
3783 		perms = MSGQ__SETATTR;
3784 		break;
3785 	case IPC_RMID:
3786 		perms = MSGQ__DESTROY;
3787 		break;
3788 	default:
3789 		return 0;
3790 	}
3791 
3792 	err = ipc_has_perm(&msq->q_perm, perms);
3793 	return err;
3794 }
3795 
3796 static int selinux_msg_queue_msgsnd(struct msg_queue *msq, struct msg_msg *msg, int msqflg)
3797 {
3798 	struct task_security_struct *tsec;
3799 	struct ipc_security_struct *isec;
3800 	struct msg_security_struct *msec;
3801 	struct avc_audit_data ad;
3802 	int rc;
3803 
3804 	tsec = current->security;
3805 	isec = msq->q_perm.security;
3806 	msec = msg->security;
3807 
3808 	/*
3809 	 * First time through, need to assign label to the message
3810 	 */
3811 	if (msec->sid == SECINITSID_UNLABELED) {
3812 		/*
3813 		 * Compute new sid based on current process and
3814 		 * message queue this message will be stored in
3815 		 */
3816 		rc = security_transition_sid(tsec->sid,
3817 					     isec->sid,
3818 					     SECCLASS_MSG,
3819 					     &msec->sid);
3820 		if (rc)
3821 			return rc;
3822 	}
3823 
3824 	AVC_AUDIT_DATA_INIT(&ad, IPC);
3825 	ad.u.ipc_id = msq->q_perm.key;
3826 
3827 	/* Can this process write to the queue? */
3828 	rc = avc_has_perm(tsec->sid, isec->sid, SECCLASS_MSGQ,
3829 			  MSGQ__WRITE, &ad);
3830 	if (!rc)
3831 		/* Can this process send the message */
3832 		rc = avc_has_perm(tsec->sid, msec->sid,
3833 				  SECCLASS_MSG, MSG__SEND, &ad);
3834 	if (!rc)
3835 		/* Can the message be put in the queue? */
3836 		rc = avc_has_perm(msec->sid, isec->sid,
3837 				  SECCLASS_MSGQ, MSGQ__ENQUEUE, &ad);
3838 
3839 	return rc;
3840 }
3841 
3842 static int selinux_msg_queue_msgrcv(struct msg_queue *msq, struct msg_msg *msg,
3843 				    struct task_struct *target,
3844 				    long type, int mode)
3845 {
3846 	struct task_security_struct *tsec;
3847 	struct ipc_security_struct *isec;
3848 	struct msg_security_struct *msec;
3849 	struct avc_audit_data ad;
3850 	int rc;
3851 
3852 	tsec = target->security;
3853 	isec = msq->q_perm.security;
3854 	msec = msg->security;
3855 
3856 	AVC_AUDIT_DATA_INIT(&ad, IPC);
3857  	ad.u.ipc_id = msq->q_perm.key;
3858 
3859 	rc = avc_has_perm(tsec->sid, isec->sid,
3860 			  SECCLASS_MSGQ, MSGQ__READ, &ad);
3861 	if (!rc)
3862 		rc = avc_has_perm(tsec->sid, msec->sid,
3863 				  SECCLASS_MSG, MSG__RECEIVE, &ad);
3864 	return rc;
3865 }
3866 
3867 /* Shared Memory security operations */
3868 static int selinux_shm_alloc_security(struct shmid_kernel *shp)
3869 {
3870 	struct task_security_struct *tsec;
3871 	struct ipc_security_struct *isec;
3872 	struct avc_audit_data ad;
3873 	int rc;
3874 
3875 	rc = ipc_alloc_security(current, &shp->shm_perm, SECCLASS_SHM);
3876 	if (rc)
3877 		return rc;
3878 
3879 	tsec = current->security;
3880 	isec = shp->shm_perm.security;
3881 
3882 	AVC_AUDIT_DATA_INIT(&ad, IPC);
3883  	ad.u.ipc_id = shp->shm_perm.key;
3884 
3885 	rc = avc_has_perm(tsec->sid, isec->sid, SECCLASS_SHM,
3886 			  SHM__CREATE, &ad);
3887 	if (rc) {
3888 		ipc_free_security(&shp->shm_perm);
3889 		return rc;
3890 	}
3891 	return 0;
3892 }
3893 
3894 static void selinux_shm_free_security(struct shmid_kernel *shp)
3895 {
3896 	ipc_free_security(&shp->shm_perm);
3897 }
3898 
3899 static int selinux_shm_associate(struct shmid_kernel *shp, int shmflg)
3900 {
3901 	struct task_security_struct *tsec;
3902 	struct ipc_security_struct *isec;
3903 	struct avc_audit_data ad;
3904 
3905 	tsec = current->security;
3906 	isec = shp->shm_perm.security;
3907 
3908 	AVC_AUDIT_DATA_INIT(&ad, IPC);
3909 	ad.u.ipc_id = shp->shm_perm.key;
3910 
3911 	return avc_has_perm(tsec->sid, isec->sid, SECCLASS_SHM,
3912 			    SHM__ASSOCIATE, &ad);
3913 }
3914 
3915 /* Note, at this point, shp is locked down */
3916 static int selinux_shm_shmctl(struct shmid_kernel *shp, int cmd)
3917 {
3918 	int perms;
3919 	int err;
3920 
3921 	switch(cmd) {
3922 	case IPC_INFO:
3923 	case SHM_INFO:
3924 		/* No specific object, just general system-wide information. */
3925 		return task_has_system(current, SYSTEM__IPC_INFO);
3926 	case IPC_STAT:
3927 	case SHM_STAT:
3928 		perms = SHM__GETATTR | SHM__ASSOCIATE;
3929 		break;
3930 	case IPC_SET:
3931 		perms = SHM__SETATTR;
3932 		break;
3933 	case SHM_LOCK:
3934 	case SHM_UNLOCK:
3935 		perms = SHM__LOCK;
3936 		break;
3937 	case IPC_RMID:
3938 		perms = SHM__DESTROY;
3939 		break;
3940 	default:
3941 		return 0;
3942 	}
3943 
3944 	err = ipc_has_perm(&shp->shm_perm, perms);
3945 	return err;
3946 }
3947 
3948 static int selinux_shm_shmat(struct shmid_kernel *shp,
3949 			     char __user *shmaddr, int shmflg)
3950 {
3951 	u32 perms;
3952 	int rc;
3953 
3954 	rc = secondary_ops->shm_shmat(shp, shmaddr, shmflg);
3955 	if (rc)
3956 		return rc;
3957 
3958 	if (shmflg & SHM_RDONLY)
3959 		perms = SHM__READ;
3960 	else
3961 		perms = SHM__READ | SHM__WRITE;
3962 
3963 	return ipc_has_perm(&shp->shm_perm, perms);
3964 }
3965 
3966 /* Semaphore security operations */
3967 static int selinux_sem_alloc_security(struct sem_array *sma)
3968 {
3969 	struct task_security_struct *tsec;
3970 	struct ipc_security_struct *isec;
3971 	struct avc_audit_data ad;
3972 	int rc;
3973 
3974 	rc = ipc_alloc_security(current, &sma->sem_perm, SECCLASS_SEM);
3975 	if (rc)
3976 		return rc;
3977 
3978 	tsec = current->security;
3979 	isec = sma->sem_perm.security;
3980 
3981 	AVC_AUDIT_DATA_INIT(&ad, IPC);
3982  	ad.u.ipc_id = sma->sem_perm.key;
3983 
3984 	rc = avc_has_perm(tsec->sid, isec->sid, SECCLASS_SEM,
3985 			  SEM__CREATE, &ad);
3986 	if (rc) {
3987 		ipc_free_security(&sma->sem_perm);
3988 		return rc;
3989 	}
3990 	return 0;
3991 }
3992 
3993 static void selinux_sem_free_security(struct sem_array *sma)
3994 {
3995 	ipc_free_security(&sma->sem_perm);
3996 }
3997 
3998 static int selinux_sem_associate(struct sem_array *sma, int semflg)
3999 {
4000 	struct task_security_struct *tsec;
4001 	struct ipc_security_struct *isec;
4002 	struct avc_audit_data ad;
4003 
4004 	tsec = current->security;
4005 	isec = sma->sem_perm.security;
4006 
4007 	AVC_AUDIT_DATA_INIT(&ad, IPC);
4008 	ad.u.ipc_id = sma->sem_perm.key;
4009 
4010 	return avc_has_perm(tsec->sid, isec->sid, SECCLASS_SEM,
4011 			    SEM__ASSOCIATE, &ad);
4012 }
4013 
4014 /* Note, at this point, sma is locked down */
4015 static int selinux_sem_semctl(struct sem_array *sma, int cmd)
4016 {
4017 	int err;
4018 	u32 perms;
4019 
4020 	switch(cmd) {
4021 	case IPC_INFO:
4022 	case SEM_INFO:
4023 		/* No specific object, just general system-wide information. */
4024 		return task_has_system(current, SYSTEM__IPC_INFO);
4025 	case GETPID:
4026 	case GETNCNT:
4027 	case GETZCNT:
4028 		perms = SEM__GETATTR;
4029 		break;
4030 	case GETVAL:
4031 	case GETALL:
4032 		perms = SEM__READ;
4033 		break;
4034 	case SETVAL:
4035 	case SETALL:
4036 		perms = SEM__WRITE;
4037 		break;
4038 	case IPC_RMID:
4039 		perms = SEM__DESTROY;
4040 		break;
4041 	case IPC_SET:
4042 		perms = SEM__SETATTR;
4043 		break;
4044 	case IPC_STAT:
4045 	case SEM_STAT:
4046 		perms = SEM__GETATTR | SEM__ASSOCIATE;
4047 		break;
4048 	default:
4049 		return 0;
4050 	}
4051 
4052 	err = ipc_has_perm(&sma->sem_perm, perms);
4053 	return err;
4054 }
4055 
4056 static int selinux_sem_semop(struct sem_array *sma,
4057 			     struct sembuf *sops, unsigned nsops, int alter)
4058 {
4059 	u32 perms;
4060 
4061 	if (alter)
4062 		perms = SEM__READ | SEM__WRITE;
4063 	else
4064 		perms = SEM__READ;
4065 
4066 	return ipc_has_perm(&sma->sem_perm, perms);
4067 }
4068 
4069 static int selinux_ipc_permission(struct kern_ipc_perm *ipcp, short flag)
4070 {
4071 	u32 av = 0;
4072 
4073 	av = 0;
4074 	if (flag & S_IRUGO)
4075 		av |= IPC__UNIX_READ;
4076 	if (flag & S_IWUGO)
4077 		av |= IPC__UNIX_WRITE;
4078 
4079 	if (av == 0)
4080 		return 0;
4081 
4082 	return ipc_has_perm(ipcp, av);
4083 }
4084 
4085 /* module stacking operations */
4086 static int selinux_register_security (const char *name, struct security_operations *ops)
4087 {
4088 	if (secondary_ops != original_ops) {
4089 		printk(KERN_INFO "%s:  There is already a secondary security "
4090 		       "module registered.\n", __FUNCTION__);
4091 		return -EINVAL;
4092  	}
4093 
4094 	secondary_ops = ops;
4095 
4096 	printk(KERN_INFO "%s:  Registering secondary module %s\n",
4097 	       __FUNCTION__,
4098 	       name);
4099 
4100 	return 0;
4101 }
4102 
4103 static int selinux_unregister_security (const char *name, struct security_operations *ops)
4104 {
4105 	if (ops != secondary_ops) {
4106 		printk (KERN_INFO "%s:  trying to unregister a security module "
4107 		        "that is not registered.\n", __FUNCTION__);
4108 		return -EINVAL;
4109 	}
4110 
4111 	secondary_ops = original_ops;
4112 
4113 	return 0;
4114 }
4115 
4116 static void selinux_d_instantiate (struct dentry *dentry, struct inode *inode)
4117 {
4118 	if (inode)
4119 		inode_doinit_with_dentry(inode, dentry);
4120 }
4121 
4122 static int selinux_getprocattr(struct task_struct *p,
4123 			       char *name, void *value, size_t size)
4124 {
4125 	struct task_security_struct *tsec;
4126 	u32 sid, len;
4127 	char *context;
4128 	int error;
4129 
4130 	if (current != p) {
4131 		error = task_has_perm(current, p, PROCESS__GETATTR);
4132 		if (error)
4133 			return error;
4134 	}
4135 
4136 	if (!size)
4137 		return -ERANGE;
4138 
4139 	tsec = p->security;
4140 
4141 	if (!strcmp(name, "current"))
4142 		sid = tsec->sid;
4143 	else if (!strcmp(name, "prev"))
4144 		sid = tsec->osid;
4145 	else if (!strcmp(name, "exec"))
4146 		sid = tsec->exec_sid;
4147 	else if (!strcmp(name, "fscreate"))
4148 		sid = tsec->create_sid;
4149 	else
4150 		return -EINVAL;
4151 
4152 	if (!sid)
4153 		return 0;
4154 
4155 	error = security_sid_to_context(sid, &context, &len);
4156 	if (error)
4157 		return error;
4158 	if (len > size) {
4159 		kfree(context);
4160 		return -ERANGE;
4161 	}
4162 	memcpy(value, context, len);
4163 	kfree(context);
4164 	return len;
4165 }
4166 
4167 static int selinux_setprocattr(struct task_struct *p,
4168 			       char *name, void *value, size_t size)
4169 {
4170 	struct task_security_struct *tsec;
4171 	u32 sid = 0;
4172 	int error;
4173 	char *str = value;
4174 
4175 	if (current != p) {
4176 		/* SELinux only allows a process to change its own
4177 		   security attributes. */
4178 		return -EACCES;
4179 	}
4180 
4181 	/*
4182 	 * Basic control over ability to set these attributes at all.
4183 	 * current == p, but we'll pass them separately in case the
4184 	 * above restriction is ever removed.
4185 	 */
4186 	if (!strcmp(name, "exec"))
4187 		error = task_has_perm(current, p, PROCESS__SETEXEC);
4188 	else if (!strcmp(name, "fscreate"))
4189 		error = task_has_perm(current, p, PROCESS__SETFSCREATE);
4190 	else if (!strcmp(name, "current"))
4191 		error = task_has_perm(current, p, PROCESS__SETCURRENT);
4192 	else
4193 		error = -EINVAL;
4194 	if (error)
4195 		return error;
4196 
4197 	/* Obtain a SID for the context, if one was specified. */
4198 	if (size && str[1] && str[1] != '\n') {
4199 		if (str[size-1] == '\n') {
4200 			str[size-1] = 0;
4201 			size--;
4202 		}
4203 		error = security_context_to_sid(value, size, &sid);
4204 		if (error)
4205 			return error;
4206 	}
4207 
4208 	/* Permission checking based on the specified context is
4209 	   performed during the actual operation (execve,
4210 	   open/mkdir/...), when we know the full context of the
4211 	   operation.  See selinux_bprm_set_security for the execve
4212 	   checks and may_create for the file creation checks. The
4213 	   operation will then fail if the context is not permitted. */
4214 	tsec = p->security;
4215 	if (!strcmp(name, "exec"))
4216 		tsec->exec_sid = sid;
4217 	else if (!strcmp(name, "fscreate"))
4218 		tsec->create_sid = sid;
4219 	else if (!strcmp(name, "current")) {
4220 		struct av_decision avd;
4221 
4222 		if (sid == 0)
4223 			return -EINVAL;
4224 
4225 		/* Only allow single threaded processes to change context */
4226 		if (atomic_read(&p->mm->mm_users) != 1) {
4227 			struct task_struct *g, *t;
4228 			struct mm_struct *mm = p->mm;
4229 			read_lock(&tasklist_lock);
4230 			do_each_thread(g, t)
4231 				if (t->mm == mm && t != p) {
4232 					read_unlock(&tasklist_lock);
4233 					return -EPERM;
4234 				}
4235 			while_each_thread(g, t);
4236 			read_unlock(&tasklist_lock);
4237                 }
4238 
4239 		/* Check permissions for the transition. */
4240 		error = avc_has_perm(tsec->sid, sid, SECCLASS_PROCESS,
4241 		                     PROCESS__DYNTRANSITION, NULL);
4242 		if (error)
4243 			return error;
4244 
4245 		/* Check for ptracing, and update the task SID if ok.
4246 		   Otherwise, leave SID unchanged and fail. */
4247 		task_lock(p);
4248 		if (p->ptrace & PT_PTRACED) {
4249 			error = avc_has_perm_noaudit(tsec->ptrace_sid, sid,
4250 						     SECCLASS_PROCESS,
4251 						     PROCESS__PTRACE, &avd);
4252 			if (!error)
4253 				tsec->sid = sid;
4254 			task_unlock(p);
4255 			avc_audit(tsec->ptrace_sid, sid, SECCLASS_PROCESS,
4256 				  PROCESS__PTRACE, &avd, error, NULL);
4257 			if (error)
4258 				return error;
4259 		} else {
4260 			tsec->sid = sid;
4261 			task_unlock(p);
4262 		}
4263 	}
4264 	else
4265 		return -EINVAL;
4266 
4267 	return size;
4268 }
4269 
4270 static struct security_operations selinux_ops = {
4271 	.ptrace =			selinux_ptrace,
4272 	.capget =			selinux_capget,
4273 	.capset_check =			selinux_capset_check,
4274 	.capset_set =			selinux_capset_set,
4275 	.sysctl =			selinux_sysctl,
4276 	.capable =			selinux_capable,
4277 	.quotactl =			selinux_quotactl,
4278 	.quota_on =			selinux_quota_on,
4279 	.syslog =			selinux_syslog,
4280 	.vm_enough_memory =		selinux_vm_enough_memory,
4281 
4282 	.netlink_send =			selinux_netlink_send,
4283         .netlink_recv =			selinux_netlink_recv,
4284 
4285 	.bprm_alloc_security =		selinux_bprm_alloc_security,
4286 	.bprm_free_security =		selinux_bprm_free_security,
4287 	.bprm_apply_creds =		selinux_bprm_apply_creds,
4288 	.bprm_post_apply_creds =	selinux_bprm_post_apply_creds,
4289 	.bprm_set_security =		selinux_bprm_set_security,
4290 	.bprm_check_security =		selinux_bprm_check_security,
4291 	.bprm_secureexec =		selinux_bprm_secureexec,
4292 
4293 	.sb_alloc_security =		selinux_sb_alloc_security,
4294 	.sb_free_security =		selinux_sb_free_security,
4295 	.sb_copy_data =			selinux_sb_copy_data,
4296 	.sb_kern_mount =	        selinux_sb_kern_mount,
4297 	.sb_statfs =			selinux_sb_statfs,
4298 	.sb_mount =			selinux_mount,
4299 	.sb_umount =			selinux_umount,
4300 
4301 	.inode_alloc_security =		selinux_inode_alloc_security,
4302 	.inode_free_security =		selinux_inode_free_security,
4303 	.inode_init_security =		selinux_inode_init_security,
4304 	.inode_create =			selinux_inode_create,
4305 	.inode_link =			selinux_inode_link,
4306 	.inode_unlink =			selinux_inode_unlink,
4307 	.inode_symlink =		selinux_inode_symlink,
4308 	.inode_mkdir =			selinux_inode_mkdir,
4309 	.inode_rmdir =			selinux_inode_rmdir,
4310 	.inode_mknod =			selinux_inode_mknod,
4311 	.inode_rename =			selinux_inode_rename,
4312 	.inode_readlink =		selinux_inode_readlink,
4313 	.inode_follow_link =		selinux_inode_follow_link,
4314 	.inode_permission =		selinux_inode_permission,
4315 	.inode_setattr =		selinux_inode_setattr,
4316 	.inode_getattr =		selinux_inode_getattr,
4317 	.inode_setxattr =		selinux_inode_setxattr,
4318 	.inode_post_setxattr =		selinux_inode_post_setxattr,
4319 	.inode_getxattr =		selinux_inode_getxattr,
4320 	.inode_listxattr =		selinux_inode_listxattr,
4321 	.inode_removexattr =		selinux_inode_removexattr,
4322 	.inode_getsecurity =            selinux_inode_getsecurity,
4323 	.inode_setsecurity =            selinux_inode_setsecurity,
4324 	.inode_listsecurity =           selinux_inode_listsecurity,
4325 
4326 	.file_permission =		selinux_file_permission,
4327 	.file_alloc_security =		selinux_file_alloc_security,
4328 	.file_free_security =		selinux_file_free_security,
4329 	.file_ioctl =			selinux_file_ioctl,
4330 	.file_mmap =			selinux_file_mmap,
4331 	.file_mprotect =		selinux_file_mprotect,
4332 	.file_lock =			selinux_file_lock,
4333 	.file_fcntl =			selinux_file_fcntl,
4334 	.file_set_fowner =		selinux_file_set_fowner,
4335 	.file_send_sigiotask =		selinux_file_send_sigiotask,
4336 	.file_receive =			selinux_file_receive,
4337 
4338 	.task_create =			selinux_task_create,
4339 	.task_alloc_security =		selinux_task_alloc_security,
4340 	.task_free_security =		selinux_task_free_security,
4341 	.task_setuid =			selinux_task_setuid,
4342 	.task_post_setuid =		selinux_task_post_setuid,
4343 	.task_setgid =			selinux_task_setgid,
4344 	.task_setpgid =			selinux_task_setpgid,
4345 	.task_getpgid =			selinux_task_getpgid,
4346 	.task_getsid =		        selinux_task_getsid,
4347 	.task_setgroups =		selinux_task_setgroups,
4348 	.task_setnice =			selinux_task_setnice,
4349 	.task_setrlimit =		selinux_task_setrlimit,
4350 	.task_setscheduler =		selinux_task_setscheduler,
4351 	.task_getscheduler =		selinux_task_getscheduler,
4352 	.task_kill =			selinux_task_kill,
4353 	.task_wait =			selinux_task_wait,
4354 	.task_prctl =			selinux_task_prctl,
4355 	.task_reparent_to_init =	selinux_task_reparent_to_init,
4356 	.task_to_inode =                selinux_task_to_inode,
4357 
4358 	.ipc_permission =		selinux_ipc_permission,
4359 
4360 	.msg_msg_alloc_security =	selinux_msg_msg_alloc_security,
4361 	.msg_msg_free_security =	selinux_msg_msg_free_security,
4362 
4363 	.msg_queue_alloc_security =	selinux_msg_queue_alloc_security,
4364 	.msg_queue_free_security =	selinux_msg_queue_free_security,
4365 	.msg_queue_associate =		selinux_msg_queue_associate,
4366 	.msg_queue_msgctl =		selinux_msg_queue_msgctl,
4367 	.msg_queue_msgsnd =		selinux_msg_queue_msgsnd,
4368 	.msg_queue_msgrcv =		selinux_msg_queue_msgrcv,
4369 
4370 	.shm_alloc_security =		selinux_shm_alloc_security,
4371 	.shm_free_security =		selinux_shm_free_security,
4372 	.shm_associate =		selinux_shm_associate,
4373 	.shm_shmctl =			selinux_shm_shmctl,
4374 	.shm_shmat =			selinux_shm_shmat,
4375 
4376 	.sem_alloc_security = 		selinux_sem_alloc_security,
4377 	.sem_free_security =  		selinux_sem_free_security,
4378 	.sem_associate =		selinux_sem_associate,
4379 	.sem_semctl =			selinux_sem_semctl,
4380 	.sem_semop =			selinux_sem_semop,
4381 
4382 	.register_security =		selinux_register_security,
4383 	.unregister_security =		selinux_unregister_security,
4384 
4385 	.d_instantiate =                selinux_d_instantiate,
4386 
4387 	.getprocattr =                  selinux_getprocattr,
4388 	.setprocattr =                  selinux_setprocattr,
4389 
4390 #ifdef CONFIG_SECURITY_NETWORK
4391         .unix_stream_connect =		selinux_socket_unix_stream_connect,
4392 	.unix_may_send =		selinux_socket_unix_may_send,
4393 
4394 	.socket_create =		selinux_socket_create,
4395 	.socket_post_create =		selinux_socket_post_create,
4396 	.socket_bind =			selinux_socket_bind,
4397 	.socket_connect =		selinux_socket_connect,
4398 	.socket_listen =		selinux_socket_listen,
4399 	.socket_accept =		selinux_socket_accept,
4400 	.socket_sendmsg =		selinux_socket_sendmsg,
4401 	.socket_recvmsg =		selinux_socket_recvmsg,
4402 	.socket_getsockname =		selinux_socket_getsockname,
4403 	.socket_getpeername =		selinux_socket_getpeername,
4404 	.socket_getsockopt =		selinux_socket_getsockopt,
4405 	.socket_setsockopt =		selinux_socket_setsockopt,
4406 	.socket_shutdown =		selinux_socket_shutdown,
4407 	.socket_sock_rcv_skb =		selinux_socket_sock_rcv_skb,
4408 	.socket_getpeersec =		selinux_socket_getpeersec,
4409 	.sk_alloc_security =		selinux_sk_alloc_security,
4410 	.sk_free_security =		selinux_sk_free_security,
4411 	.sk_getsid = 			selinux_sk_getsid_security,
4412 #endif
4413 
4414 #ifdef CONFIG_SECURITY_NETWORK_XFRM
4415 	.xfrm_policy_alloc_security =	selinux_xfrm_policy_alloc,
4416 	.xfrm_policy_clone_security =	selinux_xfrm_policy_clone,
4417 	.xfrm_policy_free_security =	selinux_xfrm_policy_free,
4418 	.xfrm_state_alloc_security =	selinux_xfrm_state_alloc,
4419 	.xfrm_state_free_security =	selinux_xfrm_state_free,
4420 	.xfrm_policy_lookup = 		selinux_xfrm_policy_lookup,
4421 #endif
4422 };
4423 
4424 static __init int selinux_init(void)
4425 {
4426 	struct task_security_struct *tsec;
4427 
4428 	if (!selinux_enabled) {
4429 		printk(KERN_INFO "SELinux:  Disabled at boot.\n");
4430 		return 0;
4431 	}
4432 
4433 	printk(KERN_INFO "SELinux:  Initializing.\n");
4434 
4435 	/* Set the security state for the initial task. */
4436 	if (task_alloc_security(current))
4437 		panic("SELinux:  Failed to initialize initial task.\n");
4438 	tsec = current->security;
4439 	tsec->osid = tsec->sid = SECINITSID_KERNEL;
4440 
4441 	avc_init();
4442 
4443 	original_ops = secondary_ops = security_ops;
4444 	if (!secondary_ops)
4445 		panic ("SELinux: No initial security operations\n");
4446 	if (register_security (&selinux_ops))
4447 		panic("SELinux: Unable to register with kernel.\n");
4448 
4449 	if (selinux_enforcing) {
4450 		printk(KERN_INFO "SELinux:  Starting in enforcing mode\n");
4451 	} else {
4452 		printk(KERN_INFO "SELinux:  Starting in permissive mode\n");
4453 	}
4454 	return 0;
4455 }
4456 
4457 void selinux_complete_init(void)
4458 {
4459 	printk(KERN_INFO "SELinux:  Completing initialization.\n");
4460 
4461 	/* Set up any superblocks initialized prior to the policy load. */
4462 	printk(KERN_INFO "SELinux:  Setting up existing superblocks.\n");
4463 	spin_lock(&sb_security_lock);
4464 next_sb:
4465 	if (!list_empty(&superblock_security_head)) {
4466 		struct superblock_security_struct *sbsec =
4467 				list_entry(superblock_security_head.next,
4468 				           struct superblock_security_struct,
4469 				           list);
4470 		struct super_block *sb = sbsec->sb;
4471 		spin_lock(&sb_lock);
4472 		sb->s_count++;
4473 		spin_unlock(&sb_lock);
4474 		spin_unlock(&sb_security_lock);
4475 		down_read(&sb->s_umount);
4476 		if (sb->s_root)
4477 			superblock_doinit(sb, NULL);
4478 		drop_super(sb);
4479 		spin_lock(&sb_security_lock);
4480 		list_del_init(&sbsec->list);
4481 		goto next_sb;
4482 	}
4483 	spin_unlock(&sb_security_lock);
4484 }
4485 
4486 /* SELinux requires early initialization in order to label
4487    all processes and objects when they are created. */
4488 security_initcall(selinux_init);
4489 
4490 #if defined(CONFIG_SECURITY_NETWORK) && defined(CONFIG_NETFILTER)
4491 
4492 static struct nf_hook_ops selinux_ipv4_op = {
4493 	.hook =		selinux_ipv4_postroute_last,
4494 	.owner =	THIS_MODULE,
4495 	.pf =		PF_INET,
4496 	.hooknum =	NF_IP_POST_ROUTING,
4497 	.priority =	NF_IP_PRI_SELINUX_LAST,
4498 };
4499 
4500 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
4501 
4502 static struct nf_hook_ops selinux_ipv6_op = {
4503 	.hook =		selinux_ipv6_postroute_last,
4504 	.owner =	THIS_MODULE,
4505 	.pf =		PF_INET6,
4506 	.hooknum =	NF_IP6_POST_ROUTING,
4507 	.priority =	NF_IP6_PRI_SELINUX_LAST,
4508 };
4509 
4510 #endif	/* IPV6 */
4511 
4512 static int __init selinux_nf_ip_init(void)
4513 {
4514 	int err = 0;
4515 
4516 	if (!selinux_enabled)
4517 		goto out;
4518 
4519 	printk(KERN_INFO "SELinux:  Registering netfilter hooks\n");
4520 
4521 	err = nf_register_hook(&selinux_ipv4_op);
4522 	if (err)
4523 		panic("SELinux: nf_register_hook for IPv4: error %d\n", err);
4524 
4525 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
4526 
4527 	err = nf_register_hook(&selinux_ipv6_op);
4528 	if (err)
4529 		panic("SELinux: nf_register_hook for IPv6: error %d\n", err);
4530 
4531 #endif	/* IPV6 */
4532 
4533 out:
4534 	return err;
4535 }
4536 
4537 __initcall(selinux_nf_ip_init);
4538 
4539 #ifdef CONFIG_SECURITY_SELINUX_DISABLE
4540 static void selinux_nf_ip_exit(void)
4541 {
4542 	printk(KERN_INFO "SELinux:  Unregistering netfilter hooks\n");
4543 
4544 	nf_unregister_hook(&selinux_ipv4_op);
4545 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
4546 	nf_unregister_hook(&selinux_ipv6_op);
4547 #endif	/* IPV6 */
4548 }
4549 #endif
4550 
4551 #else /* CONFIG_SECURITY_NETWORK && CONFIG_NETFILTER */
4552 
4553 #ifdef CONFIG_SECURITY_SELINUX_DISABLE
4554 #define selinux_nf_ip_exit()
4555 #endif
4556 
4557 #endif /* CONFIG_SECURITY_NETWORK && CONFIG_NETFILTER */
4558 
4559 #ifdef CONFIG_SECURITY_SELINUX_DISABLE
4560 int selinux_disable(void)
4561 {
4562 	extern void exit_sel_fs(void);
4563 	static int selinux_disabled = 0;
4564 
4565 	if (ss_initialized) {
4566 		/* Not permitted after initial policy load. */
4567 		return -EINVAL;
4568 	}
4569 
4570 	if (selinux_disabled) {
4571 		/* Only do this once. */
4572 		return -EINVAL;
4573 	}
4574 
4575 	printk(KERN_INFO "SELinux:  Disabled at runtime.\n");
4576 
4577 	selinux_disabled = 1;
4578 
4579 	/* Reset security_ops to the secondary module, dummy or capability. */
4580 	security_ops = secondary_ops;
4581 
4582 	/* Unregister netfilter hooks. */
4583 	selinux_nf_ip_exit();
4584 
4585 	/* Unregister selinuxfs. */
4586 	exit_sel_fs();
4587 
4588 	return 0;
4589 }
4590 #endif
4591 
4592 
4593