xref: /openbmc/linux/security/selinux/hooks.c (revision 20dd026d7f5a6972dc78b4928a99620001fa547d)
1 /*
2  *  NSA Security-Enhanced Linux (SELinux) security module
3  *
4  *  This file contains the SELinux hook function implementations.
5  *
6  *  Authors:  Stephen Smalley, <sds@epoch.ncsc.mil>
7  *            Chris Vance, <cvance@nai.com>
8  *            Wayne Salamon, <wsalamon@nai.com>
9  *            James Morris <jmorris@redhat.com>
10  *
11  *  Copyright (C) 2001,2002 Networks Associates Technology, Inc.
12  *  Copyright (C) 2003 Red Hat, Inc., James Morris <jmorris@redhat.com>
13  *  Copyright (C) 2004-2005 Trusted Computer Solutions, Inc.
14  *                          <dgoeddel@trustedcs.com>
15  *
16  *	This program is free software; you can redistribute it and/or modify
17  *	it under the terms of the GNU General Public License version 2,
18  *      as published by the Free Software Foundation.
19  */
20 
21 #include <linux/config.h>
22 #include <linux/module.h>
23 #include <linux/init.h>
24 #include <linux/kernel.h>
25 #include <linux/ptrace.h>
26 #include <linux/errno.h>
27 #include <linux/sched.h>
28 #include <linux/security.h>
29 #include <linux/xattr.h>
30 #include <linux/capability.h>
31 #include <linux/unistd.h>
32 #include <linux/mm.h>
33 #include <linux/mman.h>
34 #include <linux/slab.h>
35 #include <linux/pagemap.h>
36 #include <linux/swap.h>
37 #include <linux/smp_lock.h>
38 #include <linux/spinlock.h>
39 #include <linux/syscalls.h>
40 #include <linux/file.h>
41 #include <linux/namei.h>
42 #include <linux/mount.h>
43 #include <linux/ext2_fs.h>
44 #include <linux/proc_fs.h>
45 #include <linux/kd.h>
46 #include <linux/netfilter_ipv4.h>
47 #include <linux/netfilter_ipv6.h>
48 #include <linux/tty.h>
49 #include <net/icmp.h>
50 #include <net/ip.h>		/* for sysctl_local_port_range[] */
51 #include <net/tcp.h>		/* struct or_callable used in sock_rcv_skb */
52 #include <asm/uaccess.h>
53 #include <asm/semaphore.h>
54 #include <asm/ioctls.h>
55 #include <linux/bitops.h>
56 #include <linux/interrupt.h>
57 #include <linux/netdevice.h>	/* for network interface checks */
58 #include <linux/netlink.h>
59 #include <linux/tcp.h>
60 #include <linux/udp.h>
61 #include <linux/quota.h>
62 #include <linux/un.h>		/* for Unix socket types */
63 #include <net/af_unix.h>	/* for Unix socket types */
64 #include <linux/parser.h>
65 #include <linux/nfs_mount.h>
66 #include <net/ipv6.h>
67 #include <linux/hugetlb.h>
68 #include <linux/personality.h>
69 #include <linux/sysctl.h>
70 #include <linux/audit.h>
71 #include <linux/string.h>
72 
73 #include "avc.h"
74 #include "objsec.h"
75 #include "netif.h"
76 
77 #define XATTR_SELINUX_SUFFIX "selinux"
78 #define XATTR_NAME_SELINUX XATTR_SECURITY_PREFIX XATTR_SELINUX_SUFFIX
79 
80 extern unsigned int policydb_loaded_version;
81 extern int selinux_nlmsg_lookup(u16 sclass, u16 nlmsg_type, u32 *perm);
82 
83 #ifdef CONFIG_SECURITY_SELINUX_DEVELOP
84 int selinux_enforcing = 0;
85 
86 static int __init enforcing_setup(char *str)
87 {
88 	selinux_enforcing = simple_strtol(str,NULL,0);
89 	return 1;
90 }
91 __setup("enforcing=", enforcing_setup);
92 #endif
93 
94 #ifdef CONFIG_SECURITY_SELINUX_BOOTPARAM
95 int selinux_enabled = CONFIG_SECURITY_SELINUX_BOOTPARAM_VALUE;
96 
97 static int __init selinux_enabled_setup(char *str)
98 {
99 	selinux_enabled = simple_strtol(str, NULL, 0);
100 	return 1;
101 }
102 __setup("selinux=", selinux_enabled_setup);
103 #endif
104 
105 /* Original (dummy) security module. */
106 static struct security_operations *original_ops = NULL;
107 
108 /* Minimal support for a secondary security module,
109    just to allow the use of the dummy or capability modules.
110    The owlsm module can alternatively be used as a secondary
111    module as long as CONFIG_OWLSM_FD is not enabled. */
112 static struct security_operations *secondary_ops = NULL;
113 
114 /* Lists of inode and superblock security structures initialized
115    before the policy was loaded. */
116 static LIST_HEAD(superblock_security_head);
117 static DEFINE_SPINLOCK(sb_security_lock);
118 
119 /* Allocate and free functions for each kind of security blob. */
120 
121 static int task_alloc_security(struct task_struct *task)
122 {
123 	struct task_security_struct *tsec;
124 
125 	tsec = kmalloc(sizeof(struct task_security_struct), GFP_KERNEL);
126 	if (!tsec)
127 		return -ENOMEM;
128 
129 	memset(tsec, 0, sizeof(struct task_security_struct));
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 = kmalloc(sizeof(struct inode_security_struct), GFP_KERNEL);
155 	if (!isec)
156 		return -ENOMEM;
157 
158 	memset(isec, 0, sizeof(struct inode_security_struct));
159 	init_MUTEX(&isec->sem);
160 	INIT_LIST_HEAD(&isec->list);
161 	isec->magic = SELINUX_MAGIC;
162 	isec->inode = inode;
163 	isec->sid = SECINITSID_UNLABELED;
164 	isec->sclass = SECCLASS_FILE;
165 	if (tsec && tsec->magic == SELINUX_MAGIC)
166 		isec->task_sid = tsec->sid;
167 	else
168 		isec->task_sid = SECINITSID_UNLABELED;
169 	inode->i_security = isec;
170 
171 	return 0;
172 }
173 
174 static void inode_free_security(struct inode *inode)
175 {
176 	struct inode_security_struct *isec = inode->i_security;
177 	struct superblock_security_struct *sbsec = inode->i_sb->s_security;
178 
179 	if (!isec || isec->magic != SELINUX_MAGIC)
180 		return;
181 
182 	spin_lock(&sbsec->isec_lock);
183 	if (!list_empty(&isec->list))
184 		list_del_init(&isec->list);
185 	spin_unlock(&sbsec->isec_lock);
186 
187 	inode->i_security = NULL;
188 	kfree(isec);
189 }
190 
191 static int file_alloc_security(struct file *file)
192 {
193 	struct task_security_struct *tsec = current->security;
194 	struct file_security_struct *fsec;
195 
196 	fsec = kmalloc(sizeof(struct file_security_struct), GFP_ATOMIC);
197 	if (!fsec)
198 		return -ENOMEM;
199 
200 	memset(fsec, 0, sizeof(struct file_security_struct));
201 	fsec->magic = SELINUX_MAGIC;
202 	fsec->file = file;
203 	if (tsec && tsec->magic == SELINUX_MAGIC) {
204 		fsec->sid = tsec->sid;
205 		fsec->fown_sid = tsec->sid;
206 	} else {
207 		fsec->sid = SECINITSID_UNLABELED;
208 		fsec->fown_sid = SECINITSID_UNLABELED;
209 	}
210 	file->f_security = fsec;
211 
212 	return 0;
213 }
214 
215 static void file_free_security(struct file *file)
216 {
217 	struct file_security_struct *fsec = file->f_security;
218 
219 	if (!fsec || fsec->magic != SELINUX_MAGIC)
220 		return;
221 
222 	file->f_security = NULL;
223 	kfree(fsec);
224 }
225 
226 static int superblock_alloc_security(struct super_block *sb)
227 {
228 	struct superblock_security_struct *sbsec;
229 
230 	sbsec = kmalloc(sizeof(struct superblock_security_struct), GFP_KERNEL);
231 	if (!sbsec)
232 		return -ENOMEM;
233 
234 	memset(sbsec, 0, sizeof(struct superblock_security_struct));
235 	init_MUTEX(&sbsec->sem);
236 	INIT_LIST_HEAD(&sbsec->list);
237 	INIT_LIST_HEAD(&sbsec->isec_head);
238 	spin_lock_init(&sbsec->isec_lock);
239 	sbsec->magic = SELINUX_MAGIC;
240 	sbsec->sb = sb;
241 	sbsec->sid = SECINITSID_UNLABELED;
242 	sbsec->def_sid = SECINITSID_FILE;
243 	sb->s_security = sbsec;
244 
245 	return 0;
246 }
247 
248 static void superblock_free_security(struct super_block *sb)
249 {
250 	struct superblock_security_struct *sbsec = sb->s_security;
251 
252 	if (!sbsec || sbsec->magic != SELINUX_MAGIC)
253 		return;
254 
255 	spin_lock(&sb_security_lock);
256 	if (!list_empty(&sbsec->list))
257 		list_del_init(&sbsec->list);
258 	spin_unlock(&sb_security_lock);
259 
260 	sb->s_security = NULL;
261 	kfree(sbsec);
262 }
263 
264 #ifdef CONFIG_SECURITY_NETWORK
265 static int sk_alloc_security(struct sock *sk, int family, int priority)
266 {
267 	struct sk_security_struct *ssec;
268 
269 	if (family != PF_UNIX)
270 		return 0;
271 
272 	ssec = kmalloc(sizeof(*ssec), priority);
273 	if (!ssec)
274 		return -ENOMEM;
275 
276 	memset(ssec, 0, sizeof(*ssec));
277 	ssec->magic = SELINUX_MAGIC;
278 	ssec->sk = sk;
279 	ssec->peer_sid = SECINITSID_UNLABELED;
280 	sk->sk_security = ssec;
281 
282 	return 0;
283 }
284 
285 static void sk_free_security(struct sock *sk)
286 {
287 	struct sk_security_struct *ssec = sk->sk_security;
288 
289 	if (sk->sk_family != PF_UNIX || ssec->magic != SELINUX_MAGIC)
290 		return;
291 
292 	sk->sk_security = NULL;
293 	kfree(ssec);
294 }
295 #endif	/* CONFIG_SECURITY_NETWORK */
296 
297 /* The security server must be initialized before
298    any labeling or access decisions can be provided. */
299 extern int ss_initialized;
300 
301 /* The file system's label must be initialized prior to use. */
302 
303 static char *labeling_behaviors[6] = {
304 	"uses xattr",
305 	"uses transition SIDs",
306 	"uses task SIDs",
307 	"uses genfs_contexts",
308 	"not configured for labeling",
309 	"uses mountpoint labeling",
310 };
311 
312 static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dentry);
313 
314 static inline int inode_doinit(struct inode *inode)
315 {
316 	return inode_doinit_with_dentry(inode, NULL);
317 }
318 
319 enum {
320 	Opt_context = 1,
321 	Opt_fscontext = 2,
322 	Opt_defcontext = 4,
323 };
324 
325 static match_table_t tokens = {
326 	{Opt_context, "context=%s"},
327 	{Opt_fscontext, "fscontext=%s"},
328 	{Opt_defcontext, "defcontext=%s"},
329 };
330 
331 #define SEL_MOUNT_FAIL_MSG "SELinux:  duplicate or incompatible mount options\n"
332 
333 static int try_context_mount(struct super_block *sb, void *data)
334 {
335 	char *context = NULL, *defcontext = NULL;
336 	const char *name;
337 	u32 sid;
338 	int alloc = 0, rc = 0, seen = 0;
339 	struct task_security_struct *tsec = current->security;
340 	struct superblock_security_struct *sbsec = sb->s_security;
341 
342 	if (!data)
343 		goto out;
344 
345 	name = sb->s_type->name;
346 
347 	if (sb->s_type->fs_flags & FS_BINARY_MOUNTDATA) {
348 
349 		/* NFS we understand. */
350 		if (!strcmp(name, "nfs")) {
351 			struct nfs_mount_data *d = data;
352 
353 			if (d->version <  NFS_MOUNT_VERSION)
354 				goto out;
355 
356 			if (d->context[0]) {
357 				context = d->context;
358 				seen |= Opt_context;
359 			}
360 		} else
361 			goto out;
362 
363 	} else {
364 		/* Standard string-based options. */
365 		char *p, *options = data;
366 
367 		while ((p = strsep(&options, ",")) != NULL) {
368 			int token;
369 			substring_t args[MAX_OPT_ARGS];
370 
371 			if (!*p)
372 				continue;
373 
374 			token = match_token(p, tokens, args);
375 
376 			switch (token) {
377 			case Opt_context:
378 				if (seen) {
379 					rc = -EINVAL;
380 					printk(KERN_WARNING SEL_MOUNT_FAIL_MSG);
381 					goto out_free;
382 				}
383 				context = match_strdup(&args[0]);
384 				if (!context) {
385 					rc = -ENOMEM;
386 					goto out_free;
387 				}
388 				if (!alloc)
389 					alloc = 1;
390 				seen |= Opt_context;
391 				break;
392 
393 			case Opt_fscontext:
394 				if (seen & (Opt_context|Opt_fscontext)) {
395 					rc = -EINVAL;
396 					printk(KERN_WARNING SEL_MOUNT_FAIL_MSG);
397 					goto out_free;
398 				}
399 				context = match_strdup(&args[0]);
400 				if (!context) {
401 					rc = -ENOMEM;
402 					goto out_free;
403 				}
404 				if (!alloc)
405 					alloc = 1;
406 				seen |= Opt_fscontext;
407 				break;
408 
409 			case Opt_defcontext:
410 				if (sbsec->behavior != SECURITY_FS_USE_XATTR) {
411 					rc = -EINVAL;
412 					printk(KERN_WARNING "SELinux:  "
413 					       "defcontext option is invalid "
414 					       "for this filesystem type\n");
415 					goto out_free;
416 				}
417 				if (seen & (Opt_context|Opt_defcontext)) {
418 					rc = -EINVAL;
419 					printk(KERN_WARNING SEL_MOUNT_FAIL_MSG);
420 					goto out_free;
421 				}
422 				defcontext = match_strdup(&args[0]);
423 				if (!defcontext) {
424 					rc = -ENOMEM;
425 					goto out_free;
426 				}
427 				if (!alloc)
428 					alloc = 1;
429 				seen |= Opt_defcontext;
430 				break;
431 
432 			default:
433 				rc = -EINVAL;
434 				printk(KERN_WARNING "SELinux:  unknown mount "
435 				       "option\n");
436 				goto out_free;
437 
438 			}
439 		}
440 	}
441 
442 	if (!seen)
443 		goto out;
444 
445 	if (context) {
446 		rc = security_context_to_sid(context, strlen(context), &sid);
447 		if (rc) {
448 			printk(KERN_WARNING "SELinux: security_context_to_sid"
449 			       "(%s) failed for (dev %s, type %s) errno=%d\n",
450 			       context, sb->s_id, name, rc);
451 			goto out_free;
452 		}
453 
454 		rc = avc_has_perm(tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM,
455 		                  FILESYSTEM__RELABELFROM, NULL);
456 		if (rc)
457 			goto out_free;
458 
459 		rc = avc_has_perm(tsec->sid, sid, SECCLASS_FILESYSTEM,
460 		                  FILESYSTEM__RELABELTO, NULL);
461 		if (rc)
462 			goto out_free;
463 
464 		sbsec->sid = sid;
465 
466 		if (seen & Opt_context)
467 			sbsec->behavior = SECURITY_FS_USE_MNTPOINT;
468 	}
469 
470 	if (defcontext) {
471 		rc = security_context_to_sid(defcontext, strlen(defcontext), &sid);
472 		if (rc) {
473 			printk(KERN_WARNING "SELinux: security_context_to_sid"
474 			       "(%s) failed for (dev %s, type %s) errno=%d\n",
475 			       defcontext, sb->s_id, name, rc);
476 			goto out_free;
477 		}
478 
479 		if (sid == sbsec->def_sid)
480 			goto out_free;
481 
482 		rc = avc_has_perm(tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM,
483 				  FILESYSTEM__RELABELFROM, NULL);
484 		if (rc)
485 			goto out_free;
486 
487 		rc = avc_has_perm(sid, sbsec->sid, SECCLASS_FILESYSTEM,
488 				  FILESYSTEM__ASSOCIATE, NULL);
489 		if (rc)
490 			goto out_free;
491 
492 		sbsec->def_sid = sid;
493 	}
494 
495 out_free:
496 	if (alloc) {
497 		kfree(context);
498 		kfree(defcontext);
499 	}
500 out:
501 	return rc;
502 }
503 
504 static int superblock_doinit(struct super_block *sb, void *data)
505 {
506 	struct superblock_security_struct *sbsec = sb->s_security;
507 	struct dentry *root = sb->s_root;
508 	struct inode *inode = root->d_inode;
509 	int rc = 0;
510 
511 	down(&sbsec->sem);
512 	if (sbsec->initialized)
513 		goto out;
514 
515 	if (!ss_initialized) {
516 		/* Defer initialization until selinux_complete_init,
517 		   after the initial policy is loaded and the security
518 		   server is ready to handle calls. */
519 		spin_lock(&sb_security_lock);
520 		if (list_empty(&sbsec->list))
521 			list_add(&sbsec->list, &superblock_security_head);
522 		spin_unlock(&sb_security_lock);
523 		goto out;
524 	}
525 
526 	/* Determine the labeling behavior to use for this filesystem type. */
527 	rc = security_fs_use(sb->s_type->name, &sbsec->behavior, &sbsec->sid);
528 	if (rc) {
529 		printk(KERN_WARNING "%s:  security_fs_use(%s) returned %d\n",
530 		       __FUNCTION__, sb->s_type->name, rc);
531 		goto out;
532 	}
533 
534 	rc = try_context_mount(sb, data);
535 	if (rc)
536 		goto out;
537 
538 	if (sbsec->behavior == SECURITY_FS_USE_XATTR) {
539 		/* Make sure that the xattr handler exists and that no
540 		   error other than -ENODATA is returned by getxattr on
541 		   the root directory.  -ENODATA is ok, as this may be
542 		   the first boot of the SELinux kernel before we have
543 		   assigned xattr values to the filesystem. */
544 		if (!inode->i_op->getxattr) {
545 			printk(KERN_WARNING "SELinux: (dev %s, type %s) has no "
546 			       "xattr support\n", sb->s_id, sb->s_type->name);
547 			rc = -EOPNOTSUPP;
548 			goto out;
549 		}
550 		rc = inode->i_op->getxattr(root, XATTR_NAME_SELINUX, NULL, 0);
551 		if (rc < 0 && rc != -ENODATA) {
552 			if (rc == -EOPNOTSUPP)
553 				printk(KERN_WARNING "SELinux: (dev %s, type "
554 				       "%s) has no security xattr handler\n",
555 				       sb->s_id, sb->s_type->name);
556 			else
557 				printk(KERN_WARNING "SELinux: (dev %s, type "
558 				       "%s) getxattr errno %d\n", sb->s_id,
559 				       sb->s_type->name, -rc);
560 			goto out;
561 		}
562 	}
563 
564 	if (strcmp(sb->s_type->name, "proc") == 0)
565 		sbsec->proc = 1;
566 
567 	sbsec->initialized = 1;
568 
569 	if (sbsec->behavior > ARRAY_SIZE(labeling_behaviors)) {
570 		printk(KERN_INFO "SELinux: initialized (dev %s, type %s), unknown behavior\n",
571 		       sb->s_id, sb->s_type->name);
572 	}
573 	else {
574 		printk(KERN_INFO "SELinux: initialized (dev %s, type %s), %s\n",
575 		       sb->s_id, sb->s_type->name,
576 		       labeling_behaviors[sbsec->behavior-1]);
577 	}
578 
579 	/* Initialize the root inode. */
580 	rc = inode_doinit_with_dentry(sb->s_root->d_inode, sb->s_root);
581 
582 	/* Initialize any other inodes associated with the superblock, e.g.
583 	   inodes created prior to initial policy load or inodes created
584 	   during get_sb by a pseudo filesystem that directly
585 	   populates itself. */
586 	spin_lock(&sbsec->isec_lock);
587 next_inode:
588 	if (!list_empty(&sbsec->isec_head)) {
589 		struct inode_security_struct *isec =
590 				list_entry(sbsec->isec_head.next,
591 				           struct inode_security_struct, list);
592 		struct inode *inode = isec->inode;
593 		spin_unlock(&sbsec->isec_lock);
594 		inode = igrab(inode);
595 		if (inode) {
596 			if (!IS_PRIVATE (inode))
597 				inode_doinit(inode);
598 			iput(inode);
599 		}
600 		spin_lock(&sbsec->isec_lock);
601 		list_del_init(&isec->list);
602 		goto next_inode;
603 	}
604 	spin_unlock(&sbsec->isec_lock);
605 out:
606 	up(&sbsec->sem);
607 	return rc;
608 }
609 
610 static inline u16 inode_mode_to_security_class(umode_t mode)
611 {
612 	switch (mode & S_IFMT) {
613 	case S_IFSOCK:
614 		return SECCLASS_SOCK_FILE;
615 	case S_IFLNK:
616 		return SECCLASS_LNK_FILE;
617 	case S_IFREG:
618 		return SECCLASS_FILE;
619 	case S_IFBLK:
620 		return SECCLASS_BLK_FILE;
621 	case S_IFDIR:
622 		return SECCLASS_DIR;
623 	case S_IFCHR:
624 		return SECCLASS_CHR_FILE;
625 	case S_IFIFO:
626 		return SECCLASS_FIFO_FILE;
627 
628 	}
629 
630 	return SECCLASS_FILE;
631 }
632 
633 static inline u16 socket_type_to_security_class(int family, int type, int protocol)
634 {
635 	switch (family) {
636 	case PF_UNIX:
637 		switch (type) {
638 		case SOCK_STREAM:
639 		case SOCK_SEQPACKET:
640 			return SECCLASS_UNIX_STREAM_SOCKET;
641 		case SOCK_DGRAM:
642 			return SECCLASS_UNIX_DGRAM_SOCKET;
643 		}
644 		break;
645 	case PF_INET:
646 	case PF_INET6:
647 		switch (type) {
648 		case SOCK_STREAM:
649 			return SECCLASS_TCP_SOCKET;
650 		case SOCK_DGRAM:
651 			return SECCLASS_UDP_SOCKET;
652 		case SOCK_RAW:
653 			return SECCLASS_RAWIP_SOCKET;
654 		}
655 		break;
656 	case PF_NETLINK:
657 		switch (protocol) {
658 		case NETLINK_ROUTE:
659 			return SECCLASS_NETLINK_ROUTE_SOCKET;
660 		case NETLINK_FIREWALL:
661 			return SECCLASS_NETLINK_FIREWALL_SOCKET;
662 		case NETLINK_INET_DIAG:
663 			return SECCLASS_NETLINK_TCPDIAG_SOCKET;
664 		case NETLINK_NFLOG:
665 			return SECCLASS_NETLINK_NFLOG_SOCKET;
666 		case NETLINK_XFRM:
667 			return SECCLASS_NETLINK_XFRM_SOCKET;
668 		case NETLINK_SELINUX:
669 			return SECCLASS_NETLINK_SELINUX_SOCKET;
670 		case NETLINK_AUDIT:
671 			return SECCLASS_NETLINK_AUDIT_SOCKET;
672 		case NETLINK_IP6_FW:
673 			return SECCLASS_NETLINK_IP6FW_SOCKET;
674 		case NETLINK_DNRTMSG:
675 			return SECCLASS_NETLINK_DNRT_SOCKET;
676 		case NETLINK_KOBJECT_UEVENT:
677 			return SECCLASS_NETLINK_KOBJECT_UEVENT_SOCKET;
678 		default:
679 			return SECCLASS_NETLINK_SOCKET;
680 		}
681 	case PF_PACKET:
682 		return SECCLASS_PACKET_SOCKET;
683 	case PF_KEY:
684 		return SECCLASS_KEY_SOCKET;
685 	}
686 
687 	return SECCLASS_SOCKET;
688 }
689 
690 #ifdef CONFIG_PROC_FS
691 static int selinux_proc_get_sid(struct proc_dir_entry *de,
692 				u16 tclass,
693 				u32 *sid)
694 {
695 	int buflen, rc;
696 	char *buffer, *path, *end;
697 
698 	buffer = (char*)__get_free_page(GFP_KERNEL);
699 	if (!buffer)
700 		return -ENOMEM;
701 
702 	buflen = PAGE_SIZE;
703 	end = buffer+buflen;
704 	*--end = '\0';
705 	buflen--;
706 	path = end-1;
707 	*path = '/';
708 	while (de && de != de->parent) {
709 		buflen -= de->namelen + 1;
710 		if (buflen < 0)
711 			break;
712 		end -= de->namelen;
713 		memcpy(end, de->name, de->namelen);
714 		*--end = '/';
715 		path = end;
716 		de = de->parent;
717 	}
718 	rc = security_genfs_sid("proc", path, tclass, sid);
719 	free_page((unsigned long)buffer);
720 	return rc;
721 }
722 #else
723 static int selinux_proc_get_sid(struct proc_dir_entry *de,
724 				u16 tclass,
725 				u32 *sid)
726 {
727 	return -EINVAL;
728 }
729 #endif
730 
731 /* The inode's security attributes must be initialized before first use. */
732 static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dentry)
733 {
734 	struct superblock_security_struct *sbsec = NULL;
735 	struct inode_security_struct *isec = inode->i_security;
736 	u32 sid;
737 	struct dentry *dentry;
738 #define INITCONTEXTLEN 255
739 	char *context = NULL;
740 	unsigned len = 0;
741 	int rc = 0;
742 	int hold_sem = 0;
743 
744 	if (isec->initialized)
745 		goto out;
746 
747 	down(&isec->sem);
748 	hold_sem = 1;
749 	if (isec->initialized)
750 		goto out;
751 
752 	sbsec = inode->i_sb->s_security;
753 	if (!sbsec->initialized) {
754 		/* Defer initialization until selinux_complete_init,
755 		   after the initial policy is loaded and the security
756 		   server is ready to handle calls. */
757 		spin_lock(&sbsec->isec_lock);
758 		if (list_empty(&isec->list))
759 			list_add(&isec->list, &sbsec->isec_head);
760 		spin_unlock(&sbsec->isec_lock);
761 		goto out;
762 	}
763 
764 	switch (sbsec->behavior) {
765 	case SECURITY_FS_USE_XATTR:
766 		if (!inode->i_op->getxattr) {
767 			isec->sid = sbsec->def_sid;
768 			break;
769 		}
770 
771 		/* Need a dentry, since the xattr API requires one.
772 		   Life would be simpler if we could just pass the inode. */
773 		if (opt_dentry) {
774 			/* Called from d_instantiate or d_splice_alias. */
775 			dentry = dget(opt_dentry);
776 		} else {
777 			/* Called from selinux_complete_init, try to find a dentry. */
778 			dentry = d_find_alias(inode);
779 		}
780 		if (!dentry) {
781 			printk(KERN_WARNING "%s:  no dentry for dev=%s "
782 			       "ino=%ld\n", __FUNCTION__, inode->i_sb->s_id,
783 			       inode->i_ino);
784 			goto out;
785 		}
786 
787 		len = INITCONTEXTLEN;
788 		context = kmalloc(len, GFP_KERNEL);
789 		if (!context) {
790 			rc = -ENOMEM;
791 			dput(dentry);
792 			goto out;
793 		}
794 		rc = inode->i_op->getxattr(dentry, XATTR_NAME_SELINUX,
795 					   context, len);
796 		if (rc == -ERANGE) {
797 			/* Need a larger buffer.  Query for the right size. */
798 			rc = inode->i_op->getxattr(dentry, XATTR_NAME_SELINUX,
799 						   NULL, 0);
800 			if (rc < 0) {
801 				dput(dentry);
802 				goto out;
803 			}
804 			kfree(context);
805 			len = rc;
806 			context = kmalloc(len, GFP_KERNEL);
807 			if (!context) {
808 				rc = -ENOMEM;
809 				dput(dentry);
810 				goto out;
811 			}
812 			rc = inode->i_op->getxattr(dentry,
813 						   XATTR_NAME_SELINUX,
814 						   context, len);
815 		}
816 		dput(dentry);
817 		if (rc < 0) {
818 			if (rc != -ENODATA) {
819 				printk(KERN_WARNING "%s:  getxattr returned "
820 				       "%d for dev=%s ino=%ld\n", __FUNCTION__,
821 				       -rc, inode->i_sb->s_id, inode->i_ino);
822 				kfree(context);
823 				goto out;
824 			}
825 			/* Map ENODATA to the default file SID */
826 			sid = sbsec->def_sid;
827 			rc = 0;
828 		} else {
829 			rc = security_context_to_sid_default(context, rc, &sid,
830 			                                     sbsec->def_sid);
831 			if (rc) {
832 				printk(KERN_WARNING "%s:  context_to_sid(%s) "
833 				       "returned %d for dev=%s ino=%ld\n",
834 				       __FUNCTION__, context, -rc,
835 				       inode->i_sb->s_id, inode->i_ino);
836 				kfree(context);
837 				/* Leave with the unlabeled SID */
838 				rc = 0;
839 				break;
840 			}
841 		}
842 		kfree(context);
843 		isec->sid = sid;
844 		break;
845 	case SECURITY_FS_USE_TASK:
846 		isec->sid = isec->task_sid;
847 		break;
848 	case SECURITY_FS_USE_TRANS:
849 		/* Default to the fs SID. */
850 		isec->sid = sbsec->sid;
851 
852 		/* Try to obtain a transition SID. */
853 		isec->sclass = inode_mode_to_security_class(inode->i_mode);
854 		rc = security_transition_sid(isec->task_sid,
855 					     sbsec->sid,
856 					     isec->sclass,
857 					     &sid);
858 		if (rc)
859 			goto out;
860 		isec->sid = sid;
861 		break;
862 	default:
863 		/* Default to the fs SID. */
864 		isec->sid = sbsec->sid;
865 
866 		if (sbsec->proc) {
867 			struct proc_inode *proci = PROC_I(inode);
868 			if (proci->pde) {
869 				isec->sclass = inode_mode_to_security_class(inode->i_mode);
870 				rc = selinux_proc_get_sid(proci->pde,
871 							  isec->sclass,
872 							  &sid);
873 				if (rc)
874 					goto out;
875 				isec->sid = sid;
876 			}
877 		}
878 		break;
879 	}
880 
881 	isec->initialized = 1;
882 
883 out:
884 	if (isec->sclass == SECCLASS_FILE)
885 		isec->sclass = inode_mode_to_security_class(inode->i_mode);
886 
887 	if (hold_sem)
888 		up(&isec->sem);
889 	return rc;
890 }
891 
892 /* Convert a Linux signal to an access vector. */
893 static inline u32 signal_to_av(int sig)
894 {
895 	u32 perm = 0;
896 
897 	switch (sig) {
898 	case SIGCHLD:
899 		/* Commonly granted from child to parent. */
900 		perm = PROCESS__SIGCHLD;
901 		break;
902 	case SIGKILL:
903 		/* Cannot be caught or ignored */
904 		perm = PROCESS__SIGKILL;
905 		break;
906 	case SIGSTOP:
907 		/* Cannot be caught or ignored */
908 		perm = PROCESS__SIGSTOP;
909 		break;
910 	default:
911 		/* All other signals. */
912 		perm = PROCESS__SIGNAL;
913 		break;
914 	}
915 
916 	return perm;
917 }
918 
919 /* Check permission betweeen a pair of tasks, e.g. signal checks,
920    fork check, ptrace check, etc. */
921 static int task_has_perm(struct task_struct *tsk1,
922 			 struct task_struct *tsk2,
923 			 u32 perms)
924 {
925 	struct task_security_struct *tsec1, *tsec2;
926 
927 	tsec1 = tsk1->security;
928 	tsec2 = tsk2->security;
929 	return avc_has_perm(tsec1->sid, tsec2->sid,
930 			    SECCLASS_PROCESS, perms, NULL);
931 }
932 
933 /* Check whether a task is allowed to use a capability. */
934 static int task_has_capability(struct task_struct *tsk,
935 			       int cap)
936 {
937 	struct task_security_struct *tsec;
938 	struct avc_audit_data ad;
939 
940 	tsec = tsk->security;
941 
942 	AVC_AUDIT_DATA_INIT(&ad,CAP);
943 	ad.tsk = tsk;
944 	ad.u.cap = cap;
945 
946 	return avc_has_perm(tsec->sid, tsec->sid,
947 			    SECCLASS_CAPABILITY, CAP_TO_MASK(cap), &ad);
948 }
949 
950 /* Check whether a task is allowed to use a system operation. */
951 static int task_has_system(struct task_struct *tsk,
952 			   u32 perms)
953 {
954 	struct task_security_struct *tsec;
955 
956 	tsec = tsk->security;
957 
958 	return avc_has_perm(tsec->sid, SECINITSID_KERNEL,
959 			    SECCLASS_SYSTEM, perms, NULL);
960 }
961 
962 /* Check whether a task has a particular permission to an inode.
963    The 'adp' parameter is optional and allows other audit
964    data to be passed (e.g. the dentry). */
965 static int inode_has_perm(struct task_struct *tsk,
966 			  struct inode *inode,
967 			  u32 perms,
968 			  struct avc_audit_data *adp)
969 {
970 	struct task_security_struct *tsec;
971 	struct inode_security_struct *isec;
972 	struct avc_audit_data ad;
973 
974 	tsec = tsk->security;
975 	isec = inode->i_security;
976 
977 	if (!adp) {
978 		adp = &ad;
979 		AVC_AUDIT_DATA_INIT(&ad, FS);
980 		ad.u.fs.inode = inode;
981 	}
982 
983 	return avc_has_perm(tsec->sid, isec->sid, isec->sclass, perms, adp);
984 }
985 
986 /* Same as inode_has_perm, but pass explicit audit data containing
987    the dentry to help the auditing code to more easily generate the
988    pathname if needed. */
989 static inline int dentry_has_perm(struct task_struct *tsk,
990 				  struct vfsmount *mnt,
991 				  struct dentry *dentry,
992 				  u32 av)
993 {
994 	struct inode *inode = dentry->d_inode;
995 	struct avc_audit_data ad;
996 	AVC_AUDIT_DATA_INIT(&ad,FS);
997 	ad.u.fs.mnt = mnt;
998 	ad.u.fs.dentry = dentry;
999 	return inode_has_perm(tsk, inode, av, &ad);
1000 }
1001 
1002 /* Check whether a task can use an open file descriptor to
1003    access an inode in a given way.  Check access to the
1004    descriptor itself, and then use dentry_has_perm to
1005    check a particular permission to the file.
1006    Access to the descriptor is implicitly granted if it
1007    has the same SID as the process.  If av is zero, then
1008    access to the file is not checked, e.g. for cases
1009    where only the descriptor is affected like seek. */
1010 static inline int file_has_perm(struct task_struct *tsk,
1011 				struct file *file,
1012 				u32 av)
1013 {
1014 	struct task_security_struct *tsec = tsk->security;
1015 	struct file_security_struct *fsec = file->f_security;
1016 	struct vfsmount *mnt = file->f_vfsmnt;
1017 	struct dentry *dentry = file->f_dentry;
1018 	struct inode *inode = dentry->d_inode;
1019 	struct avc_audit_data ad;
1020 	int rc;
1021 
1022 	AVC_AUDIT_DATA_INIT(&ad, FS);
1023 	ad.u.fs.mnt = mnt;
1024 	ad.u.fs.dentry = dentry;
1025 
1026 	if (tsec->sid != fsec->sid) {
1027 		rc = avc_has_perm(tsec->sid, fsec->sid,
1028 				  SECCLASS_FD,
1029 				  FD__USE,
1030 				  &ad);
1031 		if (rc)
1032 			return rc;
1033 	}
1034 
1035 	/* av is zero if only checking access to the descriptor. */
1036 	if (av)
1037 		return inode_has_perm(tsk, inode, av, &ad);
1038 
1039 	return 0;
1040 }
1041 
1042 /* Check whether a task can create a file. */
1043 static int may_create(struct inode *dir,
1044 		      struct dentry *dentry,
1045 		      u16 tclass)
1046 {
1047 	struct task_security_struct *tsec;
1048 	struct inode_security_struct *dsec;
1049 	struct superblock_security_struct *sbsec;
1050 	u32 newsid;
1051 	struct avc_audit_data ad;
1052 	int rc;
1053 
1054 	tsec = current->security;
1055 	dsec = dir->i_security;
1056 	sbsec = dir->i_sb->s_security;
1057 
1058 	AVC_AUDIT_DATA_INIT(&ad, FS);
1059 	ad.u.fs.dentry = dentry;
1060 
1061 	rc = avc_has_perm(tsec->sid, dsec->sid, SECCLASS_DIR,
1062 			  DIR__ADD_NAME | DIR__SEARCH,
1063 			  &ad);
1064 	if (rc)
1065 		return rc;
1066 
1067 	if (tsec->create_sid && sbsec->behavior != SECURITY_FS_USE_MNTPOINT) {
1068 		newsid = tsec->create_sid;
1069 	} else {
1070 		rc = security_transition_sid(tsec->sid, dsec->sid, tclass,
1071 					     &newsid);
1072 		if (rc)
1073 			return rc;
1074 	}
1075 
1076 	rc = avc_has_perm(tsec->sid, newsid, tclass, FILE__CREATE, &ad);
1077 	if (rc)
1078 		return rc;
1079 
1080 	return avc_has_perm(newsid, sbsec->sid,
1081 			    SECCLASS_FILESYSTEM,
1082 			    FILESYSTEM__ASSOCIATE, &ad);
1083 }
1084 
1085 #define MAY_LINK   0
1086 #define MAY_UNLINK 1
1087 #define MAY_RMDIR  2
1088 
1089 /* Check whether a task can link, unlink, or rmdir a file/directory. */
1090 static int may_link(struct inode *dir,
1091 		    struct dentry *dentry,
1092 		    int kind)
1093 
1094 {
1095 	struct task_security_struct *tsec;
1096 	struct inode_security_struct *dsec, *isec;
1097 	struct avc_audit_data ad;
1098 	u32 av;
1099 	int rc;
1100 
1101 	tsec = current->security;
1102 	dsec = dir->i_security;
1103 	isec = dentry->d_inode->i_security;
1104 
1105 	AVC_AUDIT_DATA_INIT(&ad, FS);
1106 	ad.u.fs.dentry = dentry;
1107 
1108 	av = DIR__SEARCH;
1109 	av |= (kind ? DIR__REMOVE_NAME : DIR__ADD_NAME);
1110 	rc = avc_has_perm(tsec->sid, dsec->sid, SECCLASS_DIR, av, &ad);
1111 	if (rc)
1112 		return rc;
1113 
1114 	switch (kind) {
1115 	case MAY_LINK:
1116 		av = FILE__LINK;
1117 		break;
1118 	case MAY_UNLINK:
1119 		av = FILE__UNLINK;
1120 		break;
1121 	case MAY_RMDIR:
1122 		av = DIR__RMDIR;
1123 		break;
1124 	default:
1125 		printk(KERN_WARNING "may_link:  unrecognized kind %d\n", kind);
1126 		return 0;
1127 	}
1128 
1129 	rc = avc_has_perm(tsec->sid, isec->sid, isec->sclass, av, &ad);
1130 	return rc;
1131 }
1132 
1133 static inline int may_rename(struct inode *old_dir,
1134 			     struct dentry *old_dentry,
1135 			     struct inode *new_dir,
1136 			     struct dentry *new_dentry)
1137 {
1138 	struct task_security_struct *tsec;
1139 	struct inode_security_struct *old_dsec, *new_dsec, *old_isec, *new_isec;
1140 	struct avc_audit_data ad;
1141 	u32 av;
1142 	int old_is_dir, new_is_dir;
1143 	int rc;
1144 
1145 	tsec = current->security;
1146 	old_dsec = old_dir->i_security;
1147 	old_isec = old_dentry->d_inode->i_security;
1148 	old_is_dir = S_ISDIR(old_dentry->d_inode->i_mode);
1149 	new_dsec = new_dir->i_security;
1150 
1151 	AVC_AUDIT_DATA_INIT(&ad, FS);
1152 
1153 	ad.u.fs.dentry = old_dentry;
1154 	rc = avc_has_perm(tsec->sid, old_dsec->sid, SECCLASS_DIR,
1155 			  DIR__REMOVE_NAME | DIR__SEARCH, &ad);
1156 	if (rc)
1157 		return rc;
1158 	rc = avc_has_perm(tsec->sid, old_isec->sid,
1159 			  old_isec->sclass, FILE__RENAME, &ad);
1160 	if (rc)
1161 		return rc;
1162 	if (old_is_dir && new_dir != old_dir) {
1163 		rc = avc_has_perm(tsec->sid, old_isec->sid,
1164 				  old_isec->sclass, DIR__REPARENT, &ad);
1165 		if (rc)
1166 			return rc;
1167 	}
1168 
1169 	ad.u.fs.dentry = new_dentry;
1170 	av = DIR__ADD_NAME | DIR__SEARCH;
1171 	if (new_dentry->d_inode)
1172 		av |= DIR__REMOVE_NAME;
1173 	rc = avc_has_perm(tsec->sid, new_dsec->sid, SECCLASS_DIR, av, &ad);
1174 	if (rc)
1175 		return rc;
1176 	if (new_dentry->d_inode) {
1177 		new_isec = new_dentry->d_inode->i_security;
1178 		new_is_dir = S_ISDIR(new_dentry->d_inode->i_mode);
1179 		rc = avc_has_perm(tsec->sid, new_isec->sid,
1180 				  new_isec->sclass,
1181 				  (new_is_dir ? DIR__RMDIR : FILE__UNLINK), &ad);
1182 		if (rc)
1183 			return rc;
1184 	}
1185 
1186 	return 0;
1187 }
1188 
1189 /* Check whether a task can perform a filesystem operation. */
1190 static int superblock_has_perm(struct task_struct *tsk,
1191 			       struct super_block *sb,
1192 			       u32 perms,
1193 			       struct avc_audit_data *ad)
1194 {
1195 	struct task_security_struct *tsec;
1196 	struct superblock_security_struct *sbsec;
1197 
1198 	tsec = tsk->security;
1199 	sbsec = sb->s_security;
1200 	return avc_has_perm(tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM,
1201 			    perms, ad);
1202 }
1203 
1204 /* Convert a Linux mode and permission mask to an access vector. */
1205 static inline u32 file_mask_to_av(int mode, int mask)
1206 {
1207 	u32 av = 0;
1208 
1209 	if ((mode & S_IFMT) != S_IFDIR) {
1210 		if (mask & MAY_EXEC)
1211 			av |= FILE__EXECUTE;
1212 		if (mask & MAY_READ)
1213 			av |= FILE__READ;
1214 
1215 		if (mask & MAY_APPEND)
1216 			av |= FILE__APPEND;
1217 		else if (mask & MAY_WRITE)
1218 			av |= FILE__WRITE;
1219 
1220 	} else {
1221 		if (mask & MAY_EXEC)
1222 			av |= DIR__SEARCH;
1223 		if (mask & MAY_WRITE)
1224 			av |= DIR__WRITE;
1225 		if (mask & MAY_READ)
1226 			av |= DIR__READ;
1227 	}
1228 
1229 	return av;
1230 }
1231 
1232 /* Convert a Linux file to an access vector. */
1233 static inline u32 file_to_av(struct file *file)
1234 {
1235 	u32 av = 0;
1236 
1237 	if (file->f_mode & FMODE_READ)
1238 		av |= FILE__READ;
1239 	if (file->f_mode & FMODE_WRITE) {
1240 		if (file->f_flags & O_APPEND)
1241 			av |= FILE__APPEND;
1242 		else
1243 			av |= FILE__WRITE;
1244 	}
1245 
1246 	return av;
1247 }
1248 
1249 /* Set an inode's SID to a specified value. */
1250 static int inode_security_set_sid(struct inode *inode, u32 sid)
1251 {
1252 	struct inode_security_struct *isec = inode->i_security;
1253 	struct superblock_security_struct *sbsec = inode->i_sb->s_security;
1254 
1255 	if (!sbsec->initialized) {
1256 		/* Defer initialization to selinux_complete_init. */
1257 		return 0;
1258 	}
1259 
1260 	down(&isec->sem);
1261 	isec->sclass = inode_mode_to_security_class(inode->i_mode);
1262 	isec->sid = sid;
1263 	isec->initialized = 1;
1264 	up(&isec->sem);
1265 	return 0;
1266 }
1267 
1268 /* Set the security attributes on a newly created file. */
1269 static int post_create(struct inode *dir,
1270 		       struct dentry *dentry)
1271 {
1272 
1273 	struct task_security_struct *tsec;
1274 	struct inode *inode;
1275 	struct inode_security_struct *dsec;
1276 	struct superblock_security_struct *sbsec;
1277 	u32 newsid;
1278 	char *context;
1279 	unsigned int len;
1280 	int rc;
1281 
1282 	tsec = current->security;
1283 	dsec = dir->i_security;
1284 	sbsec = dir->i_sb->s_security;
1285 
1286 	inode = dentry->d_inode;
1287 	if (!inode) {
1288 		/* Some file system types (e.g. NFS) may not instantiate
1289 		   a dentry for all create operations (e.g. symlink),
1290 		   so we have to check to see if the inode is non-NULL. */
1291 		printk(KERN_WARNING "post_create:  no inode, dir (dev=%s, "
1292 		       "ino=%ld)\n", dir->i_sb->s_id, dir->i_ino);
1293 		return 0;
1294 	}
1295 
1296 	if (tsec->create_sid && sbsec->behavior != SECURITY_FS_USE_MNTPOINT) {
1297 		newsid = tsec->create_sid;
1298 	} else {
1299 		rc = security_transition_sid(tsec->sid, dsec->sid,
1300 					     inode_mode_to_security_class(inode->i_mode),
1301 					     &newsid);
1302 		if (rc) {
1303 			printk(KERN_WARNING "post_create:  "
1304 			       "security_transition_sid failed, rc=%d (dev=%s "
1305 			       "ino=%ld)\n",
1306 			       -rc, inode->i_sb->s_id, inode->i_ino);
1307 			return rc;
1308 		}
1309 	}
1310 
1311 	rc = inode_security_set_sid(inode, newsid);
1312 	if (rc) {
1313 		printk(KERN_WARNING "post_create:  inode_security_set_sid "
1314 		       "failed, rc=%d (dev=%s ino=%ld)\n",
1315 		       -rc, inode->i_sb->s_id, inode->i_ino);
1316 		return rc;
1317 	}
1318 
1319 	if (sbsec->behavior == SECURITY_FS_USE_XATTR &&
1320 	    inode->i_op->setxattr) {
1321 		/* Use extended attributes. */
1322 		rc = security_sid_to_context(newsid, &context, &len);
1323 		if (rc) {
1324 			printk(KERN_WARNING "post_create:  sid_to_context "
1325 			       "failed, rc=%d (dev=%s ino=%ld)\n",
1326 			       -rc, inode->i_sb->s_id, inode->i_ino);
1327 			return rc;
1328 		}
1329 		down(&inode->i_sem);
1330 		rc = inode->i_op->setxattr(dentry,
1331 					   XATTR_NAME_SELINUX,
1332 					   context, len, 0);
1333 		up(&inode->i_sem);
1334 		kfree(context);
1335 		if (rc < 0) {
1336 			printk(KERN_WARNING "post_create:  setxattr failed, "
1337 			       "rc=%d (dev=%s ino=%ld)\n",
1338 			       -rc, inode->i_sb->s_id, inode->i_ino);
1339 			return rc;
1340 		}
1341 	}
1342 
1343 	return 0;
1344 }
1345 
1346 
1347 /* Hook functions begin here. */
1348 
1349 static int selinux_ptrace(struct task_struct *parent, struct task_struct *child)
1350 {
1351 	struct task_security_struct *psec = parent->security;
1352 	struct task_security_struct *csec = child->security;
1353 	int rc;
1354 
1355 	rc = secondary_ops->ptrace(parent,child);
1356 	if (rc)
1357 		return rc;
1358 
1359 	rc = task_has_perm(parent, child, PROCESS__PTRACE);
1360 	/* Save the SID of the tracing process for later use in apply_creds. */
1361 	if (!rc)
1362 		csec->ptrace_sid = psec->sid;
1363 	return rc;
1364 }
1365 
1366 static int selinux_capget(struct task_struct *target, kernel_cap_t *effective,
1367                           kernel_cap_t *inheritable, kernel_cap_t *permitted)
1368 {
1369 	int error;
1370 
1371 	error = task_has_perm(current, target, PROCESS__GETCAP);
1372 	if (error)
1373 		return error;
1374 
1375 	return secondary_ops->capget(target, effective, inheritable, permitted);
1376 }
1377 
1378 static int selinux_capset_check(struct task_struct *target, kernel_cap_t *effective,
1379                                 kernel_cap_t *inheritable, kernel_cap_t *permitted)
1380 {
1381 	int error;
1382 
1383 	error = secondary_ops->capset_check(target, effective, inheritable, permitted);
1384 	if (error)
1385 		return error;
1386 
1387 	return task_has_perm(current, target, PROCESS__SETCAP);
1388 }
1389 
1390 static void selinux_capset_set(struct task_struct *target, kernel_cap_t *effective,
1391                                kernel_cap_t *inheritable, kernel_cap_t *permitted)
1392 {
1393 	secondary_ops->capset_set(target, effective, inheritable, permitted);
1394 }
1395 
1396 static int selinux_capable(struct task_struct *tsk, int cap)
1397 {
1398 	int rc;
1399 
1400 	rc = secondary_ops->capable(tsk, cap);
1401 	if (rc)
1402 		return rc;
1403 
1404 	return task_has_capability(tsk,cap);
1405 }
1406 
1407 static int selinux_sysctl(ctl_table *table, int op)
1408 {
1409 	int error = 0;
1410 	u32 av;
1411 	struct task_security_struct *tsec;
1412 	u32 tsid;
1413 	int rc;
1414 
1415 	rc = secondary_ops->sysctl(table, op);
1416 	if (rc)
1417 		return rc;
1418 
1419 	tsec = current->security;
1420 
1421 	rc = selinux_proc_get_sid(table->de, (op == 001) ?
1422 	                          SECCLASS_DIR : SECCLASS_FILE, &tsid);
1423 	if (rc) {
1424 		/* Default to the well-defined sysctl SID. */
1425 		tsid = SECINITSID_SYSCTL;
1426 	}
1427 
1428 	/* The op values are "defined" in sysctl.c, thereby creating
1429 	 * a bad coupling between this module and sysctl.c */
1430 	if(op == 001) {
1431 		error = avc_has_perm(tsec->sid, tsid,
1432 				     SECCLASS_DIR, DIR__SEARCH, NULL);
1433 	} else {
1434 		av = 0;
1435 		if (op & 004)
1436 			av |= FILE__READ;
1437 		if (op & 002)
1438 			av |= FILE__WRITE;
1439 		if (av)
1440 			error = avc_has_perm(tsec->sid, tsid,
1441 					     SECCLASS_FILE, av, NULL);
1442         }
1443 
1444 	return error;
1445 }
1446 
1447 static int selinux_quotactl(int cmds, int type, int id, struct super_block *sb)
1448 {
1449 	int rc = 0;
1450 
1451 	if (!sb)
1452 		return 0;
1453 
1454 	switch (cmds) {
1455 		case Q_SYNC:
1456 		case Q_QUOTAON:
1457 		case Q_QUOTAOFF:
1458 	        case Q_SETINFO:
1459 		case Q_SETQUOTA:
1460 			rc = superblock_has_perm(current,
1461 						 sb,
1462 						 FILESYSTEM__QUOTAMOD, NULL);
1463 			break;
1464 	        case Q_GETFMT:
1465 	        case Q_GETINFO:
1466 		case Q_GETQUOTA:
1467 			rc = superblock_has_perm(current,
1468 						 sb,
1469 						 FILESYSTEM__QUOTAGET, NULL);
1470 			break;
1471 		default:
1472 			rc = 0;  /* let the kernel handle invalid cmds */
1473 			break;
1474 	}
1475 	return rc;
1476 }
1477 
1478 static int selinux_quota_on(struct dentry *dentry)
1479 {
1480 	return dentry_has_perm(current, NULL, dentry, FILE__QUOTAON);
1481 }
1482 
1483 static int selinux_syslog(int type)
1484 {
1485 	int rc;
1486 
1487 	rc = secondary_ops->syslog(type);
1488 	if (rc)
1489 		return rc;
1490 
1491 	switch (type) {
1492 		case 3:         /* Read last kernel messages */
1493 		case 10:        /* Return size of the log buffer */
1494 			rc = task_has_system(current, SYSTEM__SYSLOG_READ);
1495 			break;
1496 		case 6:         /* Disable logging to console */
1497 		case 7:         /* Enable logging to console */
1498 		case 8:		/* Set level of messages printed to console */
1499 			rc = task_has_system(current, SYSTEM__SYSLOG_CONSOLE);
1500 			break;
1501 		case 0:         /* Close log */
1502 		case 1:         /* Open log */
1503 		case 2:         /* Read from log */
1504 		case 4:         /* Read/clear last kernel messages */
1505 		case 5:         /* Clear ring buffer */
1506 		default:
1507 			rc = task_has_system(current, SYSTEM__SYSLOG_MOD);
1508 			break;
1509 	}
1510 	return rc;
1511 }
1512 
1513 /*
1514  * Check that a process has enough memory to allocate a new virtual
1515  * mapping. 0 means there is enough memory for the allocation to
1516  * succeed and -ENOMEM implies there is not.
1517  *
1518  * Note that secondary_ops->capable and task_has_perm_noaudit return 0
1519  * if the capability is granted, but __vm_enough_memory requires 1 if
1520  * the capability is granted.
1521  *
1522  * Do not audit the selinux permission check, as this is applied to all
1523  * processes that allocate mappings.
1524  */
1525 static int selinux_vm_enough_memory(long pages)
1526 {
1527 	int rc, cap_sys_admin = 0;
1528 	struct task_security_struct *tsec = current->security;
1529 
1530 	rc = secondary_ops->capable(current, CAP_SYS_ADMIN);
1531 	if (rc == 0)
1532 		rc = avc_has_perm_noaudit(tsec->sid, tsec->sid,
1533 					SECCLASS_CAPABILITY,
1534 					CAP_TO_MASK(CAP_SYS_ADMIN),
1535 					NULL);
1536 
1537 	if (rc == 0)
1538 		cap_sys_admin = 1;
1539 
1540 	return __vm_enough_memory(pages, cap_sys_admin);
1541 }
1542 
1543 /* binprm security operations */
1544 
1545 static int selinux_bprm_alloc_security(struct linux_binprm *bprm)
1546 {
1547 	struct bprm_security_struct *bsec;
1548 
1549 	bsec = kmalloc(sizeof(struct bprm_security_struct), GFP_KERNEL);
1550 	if (!bsec)
1551 		return -ENOMEM;
1552 
1553 	memset(bsec, 0, sizeof *bsec);
1554 	bsec->magic = SELINUX_MAGIC;
1555 	bsec->bprm = bprm;
1556 	bsec->sid = SECINITSID_UNLABELED;
1557 	bsec->set = 0;
1558 
1559 	bprm->security = bsec;
1560 	return 0;
1561 }
1562 
1563 static int selinux_bprm_set_security(struct linux_binprm *bprm)
1564 {
1565 	struct task_security_struct *tsec;
1566 	struct inode *inode = bprm->file->f_dentry->d_inode;
1567 	struct inode_security_struct *isec;
1568 	struct bprm_security_struct *bsec;
1569 	u32 newsid;
1570 	struct avc_audit_data ad;
1571 	int rc;
1572 
1573 	rc = secondary_ops->bprm_set_security(bprm);
1574 	if (rc)
1575 		return rc;
1576 
1577 	bsec = bprm->security;
1578 
1579 	if (bsec->set)
1580 		return 0;
1581 
1582 	tsec = current->security;
1583 	isec = inode->i_security;
1584 
1585 	/* Default to the current task SID. */
1586 	bsec->sid = tsec->sid;
1587 
1588 	/* Reset create SID on execve. */
1589 	tsec->create_sid = 0;
1590 
1591 	if (tsec->exec_sid) {
1592 		newsid = tsec->exec_sid;
1593 		/* Reset exec SID on execve. */
1594 		tsec->exec_sid = 0;
1595 	} else {
1596 		/* Check for a default transition on this program. */
1597 		rc = security_transition_sid(tsec->sid, isec->sid,
1598 		                             SECCLASS_PROCESS, &newsid);
1599 		if (rc)
1600 			return rc;
1601 	}
1602 
1603 	AVC_AUDIT_DATA_INIT(&ad, FS);
1604 	ad.u.fs.mnt = bprm->file->f_vfsmnt;
1605 	ad.u.fs.dentry = bprm->file->f_dentry;
1606 
1607 	if (bprm->file->f_vfsmnt->mnt_flags & MNT_NOSUID)
1608 		newsid = tsec->sid;
1609 
1610         if (tsec->sid == newsid) {
1611 		rc = avc_has_perm(tsec->sid, isec->sid,
1612 				  SECCLASS_FILE, FILE__EXECUTE_NO_TRANS, &ad);
1613 		if (rc)
1614 			return rc;
1615 	} else {
1616 		/* Check permissions for the transition. */
1617 		rc = avc_has_perm(tsec->sid, newsid,
1618 				  SECCLASS_PROCESS, PROCESS__TRANSITION, &ad);
1619 		if (rc)
1620 			return rc;
1621 
1622 		rc = avc_has_perm(newsid, isec->sid,
1623 				  SECCLASS_FILE, FILE__ENTRYPOINT, &ad);
1624 		if (rc)
1625 			return rc;
1626 
1627 		/* Clear any possibly unsafe personality bits on exec: */
1628 		current->personality &= ~PER_CLEAR_ON_SETID;
1629 
1630 		/* Set the security field to the new SID. */
1631 		bsec->sid = newsid;
1632 	}
1633 
1634 	bsec->set = 1;
1635 	return 0;
1636 }
1637 
1638 static int selinux_bprm_check_security (struct linux_binprm *bprm)
1639 {
1640 	return secondary_ops->bprm_check_security(bprm);
1641 }
1642 
1643 
1644 static int selinux_bprm_secureexec (struct linux_binprm *bprm)
1645 {
1646 	struct task_security_struct *tsec = current->security;
1647 	int atsecure = 0;
1648 
1649 	if (tsec->osid != tsec->sid) {
1650 		/* Enable secure mode for SIDs transitions unless
1651 		   the noatsecure permission is granted between
1652 		   the two SIDs, i.e. ahp returns 0. */
1653 		atsecure = avc_has_perm(tsec->osid, tsec->sid,
1654 					 SECCLASS_PROCESS,
1655 					 PROCESS__NOATSECURE, NULL);
1656 	}
1657 
1658 	return (atsecure || secondary_ops->bprm_secureexec(bprm));
1659 }
1660 
1661 static void selinux_bprm_free_security(struct linux_binprm *bprm)
1662 {
1663 	kfree(bprm->security);
1664 	bprm->security = NULL;
1665 }
1666 
1667 extern struct vfsmount *selinuxfs_mount;
1668 extern struct dentry *selinux_null;
1669 
1670 /* Derived from fs/exec.c:flush_old_files. */
1671 static inline void flush_unauthorized_files(struct files_struct * files)
1672 {
1673 	struct avc_audit_data ad;
1674 	struct file *file, *devnull = NULL;
1675 	struct tty_struct *tty = current->signal->tty;
1676 	long j = -1;
1677 
1678 	if (tty) {
1679 		file_list_lock();
1680 		file = list_entry(tty->tty_files.next, typeof(*file), f_list);
1681 		if (file) {
1682 			/* Revalidate access to controlling tty.
1683 			   Use inode_has_perm on the tty inode directly rather
1684 			   than using file_has_perm, as this particular open
1685 			   file may belong to another process and we are only
1686 			   interested in the inode-based check here. */
1687 			struct inode *inode = file->f_dentry->d_inode;
1688 			if (inode_has_perm(current, inode,
1689 					   FILE__READ | FILE__WRITE, NULL)) {
1690 				/* Reset controlling tty. */
1691 				current->signal->tty = NULL;
1692 				current->signal->tty_old_pgrp = 0;
1693 			}
1694 		}
1695 		file_list_unlock();
1696 	}
1697 
1698 	/* Revalidate access to inherited open files. */
1699 
1700 	AVC_AUDIT_DATA_INIT(&ad,FS);
1701 
1702 	spin_lock(&files->file_lock);
1703 	for (;;) {
1704 		unsigned long set, i;
1705 		int fd;
1706 
1707 		j++;
1708 		i = j * __NFDBITS;
1709 		if (i >= files->max_fds || i >= files->max_fdset)
1710 			break;
1711 		set = files->open_fds->fds_bits[j];
1712 		if (!set)
1713 			continue;
1714 		spin_unlock(&files->file_lock);
1715 		for ( ; set ; i++,set >>= 1) {
1716 			if (set & 1) {
1717 				file = fget(i);
1718 				if (!file)
1719 					continue;
1720 				if (file_has_perm(current,
1721 						  file,
1722 						  file_to_av(file))) {
1723 					sys_close(i);
1724 					fd = get_unused_fd();
1725 					if (fd != i) {
1726 						if (fd >= 0)
1727 							put_unused_fd(fd);
1728 						fput(file);
1729 						continue;
1730 					}
1731 					if (devnull) {
1732 						atomic_inc(&devnull->f_count);
1733 					} else {
1734 						devnull = dentry_open(dget(selinux_null), mntget(selinuxfs_mount), O_RDWR);
1735 						if (!devnull) {
1736 							put_unused_fd(fd);
1737 							fput(file);
1738 							continue;
1739 						}
1740 					}
1741 					fd_install(fd, devnull);
1742 				}
1743 				fput(file);
1744 			}
1745 		}
1746 		spin_lock(&files->file_lock);
1747 
1748 	}
1749 	spin_unlock(&files->file_lock);
1750 }
1751 
1752 static void selinux_bprm_apply_creds(struct linux_binprm *bprm, int unsafe)
1753 {
1754 	struct task_security_struct *tsec;
1755 	struct bprm_security_struct *bsec;
1756 	u32 sid;
1757 	int rc;
1758 
1759 	secondary_ops->bprm_apply_creds(bprm, unsafe);
1760 
1761 	tsec = current->security;
1762 
1763 	bsec = bprm->security;
1764 	sid = bsec->sid;
1765 
1766 	tsec->osid = tsec->sid;
1767 	bsec->unsafe = 0;
1768 	if (tsec->sid != sid) {
1769 		/* Check for shared state.  If not ok, leave SID
1770 		   unchanged and kill. */
1771 		if (unsafe & LSM_UNSAFE_SHARE) {
1772 			rc = avc_has_perm(tsec->sid, sid, SECCLASS_PROCESS,
1773 					PROCESS__SHARE, NULL);
1774 			if (rc) {
1775 				bsec->unsafe = 1;
1776 				return;
1777 			}
1778 		}
1779 
1780 		/* Check for ptracing, and update the task SID if ok.
1781 		   Otherwise, leave SID unchanged and kill. */
1782 		if (unsafe & (LSM_UNSAFE_PTRACE | LSM_UNSAFE_PTRACE_CAP)) {
1783 			rc = avc_has_perm(tsec->ptrace_sid, sid,
1784 					  SECCLASS_PROCESS, PROCESS__PTRACE,
1785 					  NULL);
1786 			if (rc) {
1787 				bsec->unsafe = 1;
1788 				return;
1789 			}
1790 		}
1791 		tsec->sid = sid;
1792 	}
1793 }
1794 
1795 /*
1796  * called after apply_creds without the task lock held
1797  */
1798 static void selinux_bprm_post_apply_creds(struct linux_binprm *bprm)
1799 {
1800 	struct task_security_struct *tsec;
1801 	struct rlimit *rlim, *initrlim;
1802 	struct itimerval itimer;
1803 	struct bprm_security_struct *bsec;
1804 	int rc, i;
1805 
1806 	tsec = current->security;
1807 	bsec = bprm->security;
1808 
1809 	if (bsec->unsafe) {
1810 		force_sig_specific(SIGKILL, current);
1811 		return;
1812 	}
1813 	if (tsec->osid == tsec->sid)
1814 		return;
1815 
1816 	/* Close files for which the new task SID is not authorized. */
1817 	flush_unauthorized_files(current->files);
1818 
1819 	/* Check whether the new SID can inherit signal state
1820 	   from the old SID.  If not, clear itimers to avoid
1821 	   subsequent signal generation and flush and unblock
1822 	   signals. This must occur _after_ the task SID has
1823 	  been updated so that any kill done after the flush
1824 	  will be checked against the new SID. */
1825 	rc = avc_has_perm(tsec->osid, tsec->sid, SECCLASS_PROCESS,
1826 			  PROCESS__SIGINH, NULL);
1827 	if (rc) {
1828 		memset(&itimer, 0, sizeof itimer);
1829 		for (i = 0; i < 3; i++)
1830 			do_setitimer(i, &itimer, NULL);
1831 		flush_signals(current);
1832 		spin_lock_irq(&current->sighand->siglock);
1833 		flush_signal_handlers(current, 1);
1834 		sigemptyset(&current->blocked);
1835 		recalc_sigpending();
1836 		spin_unlock_irq(&current->sighand->siglock);
1837 	}
1838 
1839 	/* Check whether the new SID can inherit resource limits
1840 	   from the old SID.  If not, reset all soft limits to
1841 	   the lower of the current task's hard limit and the init
1842 	   task's soft limit.  Note that the setting of hard limits
1843 	   (even to lower them) can be controlled by the setrlimit
1844 	   check. The inclusion of the init task's soft limit into
1845 	   the computation is to avoid resetting soft limits higher
1846 	   than the default soft limit for cases where the default
1847 	   is lower than the hard limit, e.g. RLIMIT_CORE or
1848 	   RLIMIT_STACK.*/
1849 	rc = avc_has_perm(tsec->osid, tsec->sid, SECCLASS_PROCESS,
1850 			  PROCESS__RLIMITINH, NULL);
1851 	if (rc) {
1852 		for (i = 0; i < RLIM_NLIMITS; i++) {
1853 			rlim = current->signal->rlim + i;
1854 			initrlim = init_task.signal->rlim+i;
1855 			rlim->rlim_cur = min(rlim->rlim_max,initrlim->rlim_cur);
1856 		}
1857 		if (current->signal->rlim[RLIMIT_CPU].rlim_cur != RLIM_INFINITY) {
1858 			/*
1859 			 * This will cause RLIMIT_CPU calculations
1860 			 * to be refigured.
1861 			 */
1862 			current->it_prof_expires = jiffies_to_cputime(1);
1863 		}
1864 	}
1865 
1866 	/* Wake up the parent if it is waiting so that it can
1867 	   recheck wait permission to the new task SID. */
1868 	wake_up_interruptible(&current->parent->signal->wait_chldexit);
1869 }
1870 
1871 /* superblock security operations */
1872 
1873 static int selinux_sb_alloc_security(struct super_block *sb)
1874 {
1875 	return superblock_alloc_security(sb);
1876 }
1877 
1878 static void selinux_sb_free_security(struct super_block *sb)
1879 {
1880 	superblock_free_security(sb);
1881 }
1882 
1883 static inline int match_prefix(char *prefix, int plen, char *option, int olen)
1884 {
1885 	if (plen > olen)
1886 		return 0;
1887 
1888 	return !memcmp(prefix, option, plen);
1889 }
1890 
1891 static inline int selinux_option(char *option, int len)
1892 {
1893 	return (match_prefix("context=", sizeof("context=")-1, option, len) ||
1894 	        match_prefix("fscontext=", sizeof("fscontext=")-1, option, len) ||
1895 	        match_prefix("defcontext=", sizeof("defcontext=")-1, option, len));
1896 }
1897 
1898 static inline void take_option(char **to, char *from, int *first, int len)
1899 {
1900 	if (!*first) {
1901 		**to = ',';
1902 		*to += 1;
1903 	}
1904 	else
1905 		*first = 0;
1906 	memcpy(*to, from, len);
1907 	*to += len;
1908 }
1909 
1910 static int selinux_sb_copy_data(struct file_system_type *type, void *orig, void *copy)
1911 {
1912 	int fnosec, fsec, rc = 0;
1913 	char *in_save, *in_curr, *in_end;
1914 	char *sec_curr, *nosec_save, *nosec;
1915 
1916 	in_curr = orig;
1917 	sec_curr = copy;
1918 
1919 	/* Binary mount data: just copy */
1920 	if (type->fs_flags & FS_BINARY_MOUNTDATA) {
1921 		copy_page(sec_curr, in_curr);
1922 		goto out;
1923 	}
1924 
1925 	nosec = (char *)get_zeroed_page(GFP_KERNEL);
1926 	if (!nosec) {
1927 		rc = -ENOMEM;
1928 		goto out;
1929 	}
1930 
1931 	nosec_save = nosec;
1932 	fnosec = fsec = 1;
1933 	in_save = in_end = orig;
1934 
1935 	do {
1936 		if (*in_end == ',' || *in_end == '\0') {
1937 			int len = in_end - in_curr;
1938 
1939 			if (selinux_option(in_curr, len))
1940 				take_option(&sec_curr, in_curr, &fsec, len);
1941 			else
1942 				take_option(&nosec, in_curr, &fnosec, len);
1943 
1944 			in_curr = in_end + 1;
1945 		}
1946 	} while (*in_end++);
1947 
1948 	strcpy(in_save, nosec_save);
1949 	free_page((unsigned long)nosec_save);
1950 out:
1951 	return rc;
1952 }
1953 
1954 static int selinux_sb_kern_mount(struct super_block *sb, void *data)
1955 {
1956 	struct avc_audit_data ad;
1957 	int rc;
1958 
1959 	rc = superblock_doinit(sb, data);
1960 	if (rc)
1961 		return rc;
1962 
1963 	AVC_AUDIT_DATA_INIT(&ad,FS);
1964 	ad.u.fs.dentry = sb->s_root;
1965 	return superblock_has_perm(current, sb, FILESYSTEM__MOUNT, &ad);
1966 }
1967 
1968 static int selinux_sb_statfs(struct super_block *sb)
1969 {
1970 	struct avc_audit_data ad;
1971 
1972 	AVC_AUDIT_DATA_INIT(&ad,FS);
1973 	ad.u.fs.dentry = sb->s_root;
1974 	return superblock_has_perm(current, sb, FILESYSTEM__GETATTR, &ad);
1975 }
1976 
1977 static int selinux_mount(char * dev_name,
1978                          struct nameidata *nd,
1979                          char * type,
1980                          unsigned long flags,
1981                          void * data)
1982 {
1983 	int rc;
1984 
1985 	rc = secondary_ops->sb_mount(dev_name, nd, type, flags, data);
1986 	if (rc)
1987 		return rc;
1988 
1989 	if (flags & MS_REMOUNT)
1990 		return superblock_has_perm(current, nd->mnt->mnt_sb,
1991 		                           FILESYSTEM__REMOUNT, NULL);
1992 	else
1993 		return dentry_has_perm(current, nd->mnt, nd->dentry,
1994 		                       FILE__MOUNTON);
1995 }
1996 
1997 static int selinux_umount(struct vfsmount *mnt, int flags)
1998 {
1999 	int rc;
2000 
2001 	rc = secondary_ops->sb_umount(mnt, flags);
2002 	if (rc)
2003 		return rc;
2004 
2005 	return superblock_has_perm(current,mnt->mnt_sb,
2006 	                           FILESYSTEM__UNMOUNT,NULL);
2007 }
2008 
2009 /* inode security operations */
2010 
2011 static int selinux_inode_alloc_security(struct inode *inode)
2012 {
2013 	return inode_alloc_security(inode);
2014 }
2015 
2016 static void selinux_inode_free_security(struct inode *inode)
2017 {
2018 	inode_free_security(inode);
2019 }
2020 
2021 static int selinux_inode_create(struct inode *dir, struct dentry *dentry, int mask)
2022 {
2023 	return may_create(dir, dentry, SECCLASS_FILE);
2024 }
2025 
2026 static void selinux_inode_post_create(struct inode *dir, struct dentry *dentry, int mask)
2027 {
2028 	post_create(dir, dentry);
2029 }
2030 
2031 static int selinux_inode_link(struct dentry *old_dentry, struct inode *dir, struct dentry *new_dentry)
2032 {
2033 	int rc;
2034 
2035 	rc = secondary_ops->inode_link(old_dentry,dir,new_dentry);
2036 	if (rc)
2037 		return rc;
2038 	return may_link(dir, old_dentry, MAY_LINK);
2039 }
2040 
2041 static void selinux_inode_post_link(struct dentry *old_dentry, struct inode *inode, struct dentry *new_dentry)
2042 {
2043 	return;
2044 }
2045 
2046 static int selinux_inode_unlink(struct inode *dir, struct dentry *dentry)
2047 {
2048 	int rc;
2049 
2050 	rc = secondary_ops->inode_unlink(dir, dentry);
2051 	if (rc)
2052 		return rc;
2053 	return may_link(dir, dentry, MAY_UNLINK);
2054 }
2055 
2056 static int selinux_inode_symlink(struct inode *dir, struct dentry *dentry, const char *name)
2057 {
2058 	return may_create(dir, dentry, SECCLASS_LNK_FILE);
2059 }
2060 
2061 static void selinux_inode_post_symlink(struct inode *dir, struct dentry *dentry, const char *name)
2062 {
2063 	post_create(dir, dentry);
2064 }
2065 
2066 static int selinux_inode_mkdir(struct inode *dir, struct dentry *dentry, int mask)
2067 {
2068 	return may_create(dir, dentry, SECCLASS_DIR);
2069 }
2070 
2071 static void selinux_inode_post_mkdir(struct inode *dir, struct dentry *dentry, int mask)
2072 {
2073 	post_create(dir, dentry);
2074 }
2075 
2076 static int selinux_inode_rmdir(struct inode *dir, struct dentry *dentry)
2077 {
2078 	return may_link(dir, dentry, MAY_RMDIR);
2079 }
2080 
2081 static int selinux_inode_mknod(struct inode *dir, struct dentry *dentry, int mode, dev_t dev)
2082 {
2083 	int rc;
2084 
2085 	rc = secondary_ops->inode_mknod(dir, dentry, mode, dev);
2086 	if (rc)
2087 		return rc;
2088 
2089 	return may_create(dir, dentry, inode_mode_to_security_class(mode));
2090 }
2091 
2092 static void selinux_inode_post_mknod(struct inode *dir, struct dentry *dentry, int mode, dev_t dev)
2093 {
2094 	post_create(dir, dentry);
2095 }
2096 
2097 static int selinux_inode_rename(struct inode *old_inode, struct dentry *old_dentry,
2098                                 struct inode *new_inode, struct dentry *new_dentry)
2099 {
2100 	return may_rename(old_inode, old_dentry, new_inode, new_dentry);
2101 }
2102 
2103 static void selinux_inode_post_rename(struct inode *old_inode, struct dentry *old_dentry,
2104                                       struct inode *new_inode, struct dentry *new_dentry)
2105 {
2106 	return;
2107 }
2108 
2109 static int selinux_inode_readlink(struct dentry *dentry)
2110 {
2111 	return dentry_has_perm(current, NULL, dentry, FILE__READ);
2112 }
2113 
2114 static int selinux_inode_follow_link(struct dentry *dentry, struct nameidata *nameidata)
2115 {
2116 	int rc;
2117 
2118 	rc = secondary_ops->inode_follow_link(dentry,nameidata);
2119 	if (rc)
2120 		return rc;
2121 	return dentry_has_perm(current, NULL, dentry, FILE__READ);
2122 }
2123 
2124 static int selinux_inode_permission(struct inode *inode, int mask,
2125 				    struct nameidata *nd)
2126 {
2127 	int rc;
2128 
2129 	rc = secondary_ops->inode_permission(inode, mask, nd);
2130 	if (rc)
2131 		return rc;
2132 
2133 	if (!mask) {
2134 		/* No permission to check.  Existence test. */
2135 		return 0;
2136 	}
2137 
2138 	return inode_has_perm(current, inode,
2139 			       file_mask_to_av(inode->i_mode, mask), NULL);
2140 }
2141 
2142 static int selinux_inode_setattr(struct dentry *dentry, struct iattr *iattr)
2143 {
2144 	int rc;
2145 
2146 	rc = secondary_ops->inode_setattr(dentry, iattr);
2147 	if (rc)
2148 		return rc;
2149 
2150 	if (iattr->ia_valid & ATTR_FORCE)
2151 		return 0;
2152 
2153 	if (iattr->ia_valid & (ATTR_MODE | ATTR_UID | ATTR_GID |
2154 			       ATTR_ATIME_SET | ATTR_MTIME_SET))
2155 		return dentry_has_perm(current, NULL, dentry, FILE__SETATTR);
2156 
2157 	return dentry_has_perm(current, NULL, dentry, FILE__WRITE);
2158 }
2159 
2160 static int selinux_inode_getattr(struct vfsmount *mnt, struct dentry *dentry)
2161 {
2162 	return dentry_has_perm(current, mnt, dentry, FILE__GETATTR);
2163 }
2164 
2165 static int selinux_inode_setxattr(struct dentry *dentry, char *name, void *value, size_t size, int flags)
2166 {
2167 	struct task_security_struct *tsec = current->security;
2168 	struct inode *inode = dentry->d_inode;
2169 	struct inode_security_struct *isec = inode->i_security;
2170 	struct superblock_security_struct *sbsec;
2171 	struct avc_audit_data ad;
2172 	u32 newsid;
2173 	int rc = 0;
2174 
2175 	if (strcmp(name, XATTR_NAME_SELINUX)) {
2176 		if (!strncmp(name, XATTR_SECURITY_PREFIX,
2177 			     sizeof XATTR_SECURITY_PREFIX - 1) &&
2178 		    !capable(CAP_SYS_ADMIN)) {
2179 			/* A different attribute in the security namespace.
2180 			   Restrict to administrator. */
2181 			return -EPERM;
2182 		}
2183 
2184 		/* Not an attribute we recognize, so just check the
2185 		   ordinary setattr permission. */
2186 		return dentry_has_perm(current, NULL, dentry, FILE__SETATTR);
2187 	}
2188 
2189 	sbsec = inode->i_sb->s_security;
2190 	if (sbsec->behavior == SECURITY_FS_USE_MNTPOINT)
2191 		return -EOPNOTSUPP;
2192 
2193 	if ((current->fsuid != inode->i_uid) && !capable(CAP_FOWNER))
2194 		return -EPERM;
2195 
2196 	AVC_AUDIT_DATA_INIT(&ad,FS);
2197 	ad.u.fs.dentry = dentry;
2198 
2199 	rc = avc_has_perm(tsec->sid, isec->sid, isec->sclass,
2200 			  FILE__RELABELFROM, &ad);
2201 	if (rc)
2202 		return rc;
2203 
2204 	rc = security_context_to_sid(value, size, &newsid);
2205 	if (rc)
2206 		return rc;
2207 
2208 	rc = avc_has_perm(tsec->sid, newsid, isec->sclass,
2209 			  FILE__RELABELTO, &ad);
2210 	if (rc)
2211 		return rc;
2212 
2213 	rc = security_validate_transition(isec->sid, newsid, tsec->sid,
2214 	                                  isec->sclass);
2215 	if (rc)
2216 		return rc;
2217 
2218 	return avc_has_perm(newsid,
2219 			    sbsec->sid,
2220 			    SECCLASS_FILESYSTEM,
2221 			    FILESYSTEM__ASSOCIATE,
2222 			    &ad);
2223 }
2224 
2225 static void selinux_inode_post_setxattr(struct dentry *dentry, char *name,
2226                                         void *value, size_t size, int flags)
2227 {
2228 	struct inode *inode = dentry->d_inode;
2229 	struct inode_security_struct *isec = inode->i_security;
2230 	u32 newsid;
2231 	int rc;
2232 
2233 	if (strcmp(name, XATTR_NAME_SELINUX)) {
2234 		/* Not an attribute we recognize, so nothing to do. */
2235 		return;
2236 	}
2237 
2238 	rc = security_context_to_sid(value, size, &newsid);
2239 	if (rc) {
2240 		printk(KERN_WARNING "%s:  unable to obtain SID for context "
2241 		       "%s, rc=%d\n", __FUNCTION__, (char*)value, -rc);
2242 		return;
2243 	}
2244 
2245 	isec->sid = newsid;
2246 	return;
2247 }
2248 
2249 static int selinux_inode_getxattr (struct dentry *dentry, char *name)
2250 {
2251 	struct inode *inode = dentry->d_inode;
2252 	struct superblock_security_struct *sbsec = inode->i_sb->s_security;
2253 
2254 	if (sbsec->behavior == SECURITY_FS_USE_MNTPOINT)
2255 		return -EOPNOTSUPP;
2256 
2257 	return dentry_has_perm(current, NULL, dentry, FILE__GETATTR);
2258 }
2259 
2260 static int selinux_inode_listxattr (struct dentry *dentry)
2261 {
2262 	return dentry_has_perm(current, NULL, dentry, FILE__GETATTR);
2263 }
2264 
2265 static int selinux_inode_removexattr (struct dentry *dentry, char *name)
2266 {
2267 	if (strcmp(name, XATTR_NAME_SELINUX)) {
2268 		if (!strncmp(name, XATTR_SECURITY_PREFIX,
2269 			     sizeof XATTR_SECURITY_PREFIX - 1) &&
2270 		    !capable(CAP_SYS_ADMIN)) {
2271 			/* A different attribute in the security namespace.
2272 			   Restrict to administrator. */
2273 			return -EPERM;
2274 		}
2275 
2276 		/* Not an attribute we recognize, so just check the
2277 		   ordinary setattr permission. Might want a separate
2278 		   permission for removexattr. */
2279 		return dentry_has_perm(current, NULL, dentry, FILE__SETATTR);
2280 	}
2281 
2282 	/* No one is allowed to remove a SELinux security label.
2283 	   You can change the label, but all data must be labeled. */
2284 	return -EACCES;
2285 }
2286 
2287 static int selinux_inode_getsecurity(struct inode *inode, const char *name, void *buffer, size_t size)
2288 {
2289 	struct inode_security_struct *isec = inode->i_security;
2290 	char *context;
2291 	unsigned len;
2292 	int rc;
2293 
2294 	/* Permission check handled by selinux_inode_getxattr hook.*/
2295 
2296 	if (strcmp(name, XATTR_SELINUX_SUFFIX))
2297 		return -EOPNOTSUPP;
2298 
2299 	rc = security_sid_to_context(isec->sid, &context, &len);
2300 	if (rc)
2301 		return rc;
2302 
2303 	if (!buffer || !size) {
2304 		kfree(context);
2305 		return len;
2306 	}
2307 	if (size < len) {
2308 		kfree(context);
2309 		return -ERANGE;
2310 	}
2311 	memcpy(buffer, context, len);
2312 	kfree(context);
2313 	return len;
2314 }
2315 
2316 static int selinux_inode_setsecurity(struct inode *inode, const char *name,
2317                                      const void *value, size_t size, int flags)
2318 {
2319 	struct inode_security_struct *isec = inode->i_security;
2320 	u32 newsid;
2321 	int rc;
2322 
2323 	if (strcmp(name, XATTR_SELINUX_SUFFIX))
2324 		return -EOPNOTSUPP;
2325 
2326 	if (!value || !size)
2327 		return -EACCES;
2328 
2329 	rc = security_context_to_sid((void*)value, size, &newsid);
2330 	if (rc)
2331 		return rc;
2332 
2333 	isec->sid = newsid;
2334 	return 0;
2335 }
2336 
2337 static int selinux_inode_listsecurity(struct inode *inode, char *buffer, size_t buffer_size)
2338 {
2339 	const int len = sizeof(XATTR_NAME_SELINUX);
2340 	if (buffer && len <= buffer_size)
2341 		memcpy(buffer, XATTR_NAME_SELINUX, len);
2342 	return len;
2343 }
2344 
2345 /* file security operations */
2346 
2347 static int selinux_file_permission(struct file *file, int mask)
2348 {
2349 	struct inode *inode = file->f_dentry->d_inode;
2350 
2351 	if (!mask) {
2352 		/* No permission to check.  Existence test. */
2353 		return 0;
2354 	}
2355 
2356 	/* file_mask_to_av won't add FILE__WRITE if MAY_APPEND is set */
2357 	if ((file->f_flags & O_APPEND) && (mask & MAY_WRITE))
2358 		mask |= MAY_APPEND;
2359 
2360 	return file_has_perm(current, file,
2361 			     file_mask_to_av(inode->i_mode, mask));
2362 }
2363 
2364 static int selinux_file_alloc_security(struct file *file)
2365 {
2366 	return file_alloc_security(file);
2367 }
2368 
2369 static void selinux_file_free_security(struct file *file)
2370 {
2371 	file_free_security(file);
2372 }
2373 
2374 static int selinux_file_ioctl(struct file *file, unsigned int cmd,
2375 			      unsigned long arg)
2376 {
2377 	int error = 0;
2378 
2379 	switch (cmd) {
2380 		case FIONREAD:
2381 		/* fall through */
2382 		case FIBMAP:
2383 		/* fall through */
2384 		case FIGETBSZ:
2385 		/* fall through */
2386 		case EXT2_IOC_GETFLAGS:
2387 		/* fall through */
2388 		case EXT2_IOC_GETVERSION:
2389 			error = file_has_perm(current, file, FILE__GETATTR);
2390 			break;
2391 
2392 		case EXT2_IOC_SETFLAGS:
2393 		/* fall through */
2394 		case EXT2_IOC_SETVERSION:
2395 			error = file_has_perm(current, file, FILE__SETATTR);
2396 			break;
2397 
2398 		/* sys_ioctl() checks */
2399 		case FIONBIO:
2400 		/* fall through */
2401 		case FIOASYNC:
2402 			error = file_has_perm(current, file, 0);
2403 			break;
2404 
2405 	        case KDSKBENT:
2406 	        case KDSKBSENT:
2407 			error = task_has_capability(current,CAP_SYS_TTY_CONFIG);
2408 			break;
2409 
2410 		/* default case assumes that the command will go
2411 		 * to the file's ioctl() function.
2412 		 */
2413 		default:
2414 			error = file_has_perm(current, file, FILE__IOCTL);
2415 
2416 	}
2417 	return error;
2418 }
2419 
2420 static int file_map_prot_check(struct file *file, unsigned long prot, int shared)
2421 {
2422 #ifndef CONFIG_PPC32
2423 	if ((prot & PROT_EXEC) && (!file || (!shared && (prot & PROT_WRITE)))) {
2424 		/*
2425 		 * We are making executable an anonymous mapping or a
2426 		 * private file mapping that will also be writable.
2427 		 * This has an additional check.
2428 		 */
2429 		int rc = task_has_perm(current, current, PROCESS__EXECMEM);
2430 		if (rc)
2431 			return rc;
2432 	}
2433 #endif
2434 
2435 	if (file) {
2436 		/* read access is always possible with a mapping */
2437 		u32 av = FILE__READ;
2438 
2439 		/* write access only matters if the mapping is shared */
2440 		if (shared && (prot & PROT_WRITE))
2441 			av |= FILE__WRITE;
2442 
2443 		if (prot & PROT_EXEC)
2444 			av |= FILE__EXECUTE;
2445 
2446 		return file_has_perm(current, file, av);
2447 	}
2448 	return 0;
2449 }
2450 
2451 static int selinux_file_mmap(struct file *file, unsigned long reqprot,
2452 			     unsigned long prot, unsigned long flags)
2453 {
2454 	int rc;
2455 
2456 	rc = secondary_ops->file_mmap(file, reqprot, prot, flags);
2457 	if (rc)
2458 		return rc;
2459 
2460 	if (selinux_checkreqprot)
2461 		prot = reqprot;
2462 
2463 	return file_map_prot_check(file, prot,
2464 				   (flags & MAP_TYPE) == MAP_SHARED);
2465 }
2466 
2467 static int selinux_file_mprotect(struct vm_area_struct *vma,
2468 				 unsigned long reqprot,
2469 				 unsigned long prot)
2470 {
2471 	int rc;
2472 
2473 	rc = secondary_ops->file_mprotect(vma, reqprot, prot);
2474 	if (rc)
2475 		return rc;
2476 
2477 	if (selinux_checkreqprot)
2478 		prot = reqprot;
2479 
2480 #ifndef CONFIG_PPC32
2481 	if ((prot & PROT_EXEC) && !(vma->vm_flags & VM_EXECUTABLE) &&
2482 	   (vma->vm_start >= vma->vm_mm->start_brk &&
2483 	    vma->vm_end <= vma->vm_mm->brk)) {
2484 	    	/*
2485 		 * We are making an executable mapping in the brk region.
2486 		 * This has an additional execheap check.
2487 		 */
2488 		rc = task_has_perm(current, current, PROCESS__EXECHEAP);
2489 		if (rc)
2490 			return rc;
2491 	}
2492 	if (vma->vm_file != NULL && vma->anon_vma != NULL && (prot & PROT_EXEC)) {
2493 		/*
2494 		 * We are making executable a file mapping that has
2495 		 * had some COW done. Since pages might have been written,
2496 		 * check ability to execute the possibly modified content.
2497 		 * This typically should only occur for text relocations.
2498 		 */
2499 		int rc = file_has_perm(current, vma->vm_file, FILE__EXECMOD);
2500 		if (rc)
2501 			return rc;
2502 	}
2503 	if (!vma->vm_file && (prot & PROT_EXEC) &&
2504 		vma->vm_start <= vma->vm_mm->start_stack &&
2505 		vma->vm_end >= vma->vm_mm->start_stack) {
2506 		/* Attempt to make the process stack executable.
2507 		 * This has an additional execstack check.
2508 		 */
2509 		rc = task_has_perm(current, current, PROCESS__EXECSTACK);
2510 		if (rc)
2511 			return rc;
2512 	}
2513 #endif
2514 
2515 	return file_map_prot_check(vma->vm_file, prot, vma->vm_flags&VM_SHARED);
2516 }
2517 
2518 static int selinux_file_lock(struct file *file, unsigned int cmd)
2519 {
2520 	return file_has_perm(current, file, FILE__LOCK);
2521 }
2522 
2523 static int selinux_file_fcntl(struct file *file, unsigned int cmd,
2524 			      unsigned long arg)
2525 {
2526 	int err = 0;
2527 
2528 	switch (cmd) {
2529 	        case F_SETFL:
2530 			if (!file->f_dentry || !file->f_dentry->d_inode) {
2531 				err = -EINVAL;
2532 				break;
2533 			}
2534 
2535 			if ((file->f_flags & O_APPEND) && !(arg & O_APPEND)) {
2536 				err = file_has_perm(current, file,FILE__WRITE);
2537 				break;
2538 			}
2539 			/* fall through */
2540 	        case F_SETOWN:
2541 	        case F_SETSIG:
2542 	        case F_GETFL:
2543 	        case F_GETOWN:
2544 	        case F_GETSIG:
2545 			/* Just check FD__USE permission */
2546 			err = file_has_perm(current, file, 0);
2547 			break;
2548 		case F_GETLK:
2549 		case F_SETLK:
2550 	        case F_SETLKW:
2551 #if BITS_PER_LONG == 32
2552 	        case F_GETLK64:
2553 		case F_SETLK64:
2554 	        case F_SETLKW64:
2555 #endif
2556 			if (!file->f_dentry || !file->f_dentry->d_inode) {
2557 				err = -EINVAL;
2558 				break;
2559 			}
2560 			err = file_has_perm(current, file, FILE__LOCK);
2561 			break;
2562 	}
2563 
2564 	return err;
2565 }
2566 
2567 static int selinux_file_set_fowner(struct file *file)
2568 {
2569 	struct task_security_struct *tsec;
2570 	struct file_security_struct *fsec;
2571 
2572 	tsec = current->security;
2573 	fsec = file->f_security;
2574 	fsec->fown_sid = tsec->sid;
2575 
2576 	return 0;
2577 }
2578 
2579 static int selinux_file_send_sigiotask(struct task_struct *tsk,
2580 				       struct fown_struct *fown, int signum)
2581 {
2582         struct file *file;
2583 	u32 perm;
2584 	struct task_security_struct *tsec;
2585 	struct file_security_struct *fsec;
2586 
2587 	/* struct fown_struct is never outside the context of a struct file */
2588         file = (struct file *)((long)fown - offsetof(struct file,f_owner));
2589 
2590 	tsec = tsk->security;
2591 	fsec = file->f_security;
2592 
2593 	if (!signum)
2594 		perm = signal_to_av(SIGIO); /* as per send_sigio_to_task */
2595 	else
2596 		perm = signal_to_av(signum);
2597 
2598 	return avc_has_perm(fsec->fown_sid, tsec->sid,
2599 			    SECCLASS_PROCESS, perm, NULL);
2600 }
2601 
2602 static int selinux_file_receive(struct file *file)
2603 {
2604 	return file_has_perm(current, file, file_to_av(file));
2605 }
2606 
2607 /* task security operations */
2608 
2609 static int selinux_task_create(unsigned long clone_flags)
2610 {
2611 	int rc;
2612 
2613 	rc = secondary_ops->task_create(clone_flags);
2614 	if (rc)
2615 		return rc;
2616 
2617 	return task_has_perm(current, current, PROCESS__FORK);
2618 }
2619 
2620 static int selinux_task_alloc_security(struct task_struct *tsk)
2621 {
2622 	struct task_security_struct *tsec1, *tsec2;
2623 	int rc;
2624 
2625 	tsec1 = current->security;
2626 
2627 	rc = task_alloc_security(tsk);
2628 	if (rc)
2629 		return rc;
2630 	tsec2 = tsk->security;
2631 
2632 	tsec2->osid = tsec1->osid;
2633 	tsec2->sid = tsec1->sid;
2634 
2635 	/* Retain the exec and create SIDs across fork */
2636 	tsec2->exec_sid = tsec1->exec_sid;
2637 	tsec2->create_sid = tsec1->create_sid;
2638 
2639 	/* Retain ptracer SID across fork, if any.
2640 	   This will be reset by the ptrace hook upon any
2641 	   subsequent ptrace_attach operations. */
2642 	tsec2->ptrace_sid = tsec1->ptrace_sid;
2643 
2644 	return 0;
2645 }
2646 
2647 static void selinux_task_free_security(struct task_struct *tsk)
2648 {
2649 	task_free_security(tsk);
2650 }
2651 
2652 static int selinux_task_setuid(uid_t id0, uid_t id1, uid_t id2, int flags)
2653 {
2654 	/* Since setuid only affects the current process, and
2655 	   since the SELinux controls are not based on the Linux
2656 	   identity attributes, SELinux does not need to control
2657 	   this operation.  However, SELinux does control the use
2658 	   of the CAP_SETUID and CAP_SETGID capabilities using the
2659 	   capable hook. */
2660 	return 0;
2661 }
2662 
2663 static int selinux_task_post_setuid(uid_t id0, uid_t id1, uid_t id2, int flags)
2664 {
2665 	return secondary_ops->task_post_setuid(id0,id1,id2,flags);
2666 }
2667 
2668 static int selinux_task_setgid(gid_t id0, gid_t id1, gid_t id2, int flags)
2669 {
2670 	/* See the comment for setuid above. */
2671 	return 0;
2672 }
2673 
2674 static int selinux_task_setpgid(struct task_struct *p, pid_t pgid)
2675 {
2676 	return task_has_perm(current, p, PROCESS__SETPGID);
2677 }
2678 
2679 static int selinux_task_getpgid(struct task_struct *p)
2680 {
2681 	return task_has_perm(current, p, PROCESS__GETPGID);
2682 }
2683 
2684 static int selinux_task_getsid(struct task_struct *p)
2685 {
2686 	return task_has_perm(current, p, PROCESS__GETSESSION);
2687 }
2688 
2689 static int selinux_task_setgroups(struct group_info *group_info)
2690 {
2691 	/* See the comment for setuid above. */
2692 	return 0;
2693 }
2694 
2695 static int selinux_task_setnice(struct task_struct *p, int nice)
2696 {
2697 	int rc;
2698 
2699 	rc = secondary_ops->task_setnice(p, nice);
2700 	if (rc)
2701 		return rc;
2702 
2703 	return task_has_perm(current,p, PROCESS__SETSCHED);
2704 }
2705 
2706 static int selinux_task_setrlimit(unsigned int resource, struct rlimit *new_rlim)
2707 {
2708 	struct rlimit *old_rlim = current->signal->rlim + resource;
2709 	int rc;
2710 
2711 	rc = secondary_ops->task_setrlimit(resource, new_rlim);
2712 	if (rc)
2713 		return rc;
2714 
2715 	/* Control the ability to change the hard limit (whether
2716 	   lowering or raising it), so that the hard limit can
2717 	   later be used as a safe reset point for the soft limit
2718 	   upon context transitions. See selinux_bprm_apply_creds. */
2719 	if (old_rlim->rlim_max != new_rlim->rlim_max)
2720 		return task_has_perm(current, current, PROCESS__SETRLIMIT);
2721 
2722 	return 0;
2723 }
2724 
2725 static int selinux_task_setscheduler(struct task_struct *p, int policy, struct sched_param *lp)
2726 {
2727 	return task_has_perm(current, p, PROCESS__SETSCHED);
2728 }
2729 
2730 static int selinux_task_getscheduler(struct task_struct *p)
2731 {
2732 	return task_has_perm(current, p, PROCESS__GETSCHED);
2733 }
2734 
2735 static int selinux_task_kill(struct task_struct *p, struct siginfo *info, int sig)
2736 {
2737 	u32 perm;
2738 	int rc;
2739 
2740 	rc = secondary_ops->task_kill(p, info, sig);
2741 	if (rc)
2742 		return rc;
2743 
2744 	if (info && ((unsigned long)info == 1 ||
2745 	             (unsigned long)info == 2 || SI_FROMKERNEL(info)))
2746 		return 0;
2747 
2748 	if (!sig)
2749 		perm = PROCESS__SIGNULL; /* null signal; existence test */
2750 	else
2751 		perm = signal_to_av(sig);
2752 
2753 	return task_has_perm(current, p, perm);
2754 }
2755 
2756 static int selinux_task_prctl(int option,
2757 			      unsigned long arg2,
2758 			      unsigned long arg3,
2759 			      unsigned long arg4,
2760 			      unsigned long arg5)
2761 {
2762 	/* The current prctl operations do not appear to require
2763 	   any SELinux controls since they merely observe or modify
2764 	   the state of the current process. */
2765 	return 0;
2766 }
2767 
2768 static int selinux_task_wait(struct task_struct *p)
2769 {
2770 	u32 perm;
2771 
2772 	perm = signal_to_av(p->exit_signal);
2773 
2774 	return task_has_perm(p, current, perm);
2775 }
2776 
2777 static void selinux_task_reparent_to_init(struct task_struct *p)
2778 {
2779   	struct task_security_struct *tsec;
2780 
2781 	secondary_ops->task_reparent_to_init(p);
2782 
2783 	tsec = p->security;
2784 	tsec->osid = tsec->sid;
2785 	tsec->sid = SECINITSID_KERNEL;
2786 	return;
2787 }
2788 
2789 static void selinux_task_to_inode(struct task_struct *p,
2790 				  struct inode *inode)
2791 {
2792 	struct task_security_struct *tsec = p->security;
2793 	struct inode_security_struct *isec = inode->i_security;
2794 
2795 	isec->sid = tsec->sid;
2796 	isec->initialized = 1;
2797 	return;
2798 }
2799 
2800 #ifdef CONFIG_SECURITY_NETWORK
2801 
2802 /* Returns error only if unable to parse addresses */
2803 static int selinux_parse_skb_ipv4(struct sk_buff *skb, struct avc_audit_data *ad)
2804 {
2805 	int offset, ihlen, ret = -EINVAL;
2806 	struct iphdr _iph, *ih;
2807 
2808 	offset = skb->nh.raw - skb->data;
2809 	ih = skb_header_pointer(skb, offset, sizeof(_iph), &_iph);
2810 	if (ih == NULL)
2811 		goto out;
2812 
2813 	ihlen = ih->ihl * 4;
2814 	if (ihlen < sizeof(_iph))
2815 		goto out;
2816 
2817 	ad->u.net.v4info.saddr = ih->saddr;
2818 	ad->u.net.v4info.daddr = ih->daddr;
2819 	ret = 0;
2820 
2821 	switch (ih->protocol) {
2822         case IPPROTO_TCP: {
2823         	struct tcphdr _tcph, *th;
2824 
2825         	if (ntohs(ih->frag_off) & IP_OFFSET)
2826         		break;
2827 
2828 		offset += ihlen;
2829 		th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph);
2830 		if (th == NULL)
2831 			break;
2832 
2833 		ad->u.net.sport = th->source;
2834 		ad->u.net.dport = th->dest;
2835 		break;
2836         }
2837 
2838         case IPPROTO_UDP: {
2839         	struct udphdr _udph, *uh;
2840 
2841         	if (ntohs(ih->frag_off) & IP_OFFSET)
2842         		break;
2843 
2844 		offset += ihlen;
2845         	uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph);
2846 		if (uh == NULL)
2847 			break;
2848 
2849         	ad->u.net.sport = uh->source;
2850         	ad->u.net.dport = uh->dest;
2851         	break;
2852         }
2853 
2854         default:
2855         	break;
2856         }
2857 out:
2858 	return ret;
2859 }
2860 
2861 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
2862 
2863 /* Returns error only if unable to parse addresses */
2864 static int selinux_parse_skb_ipv6(struct sk_buff *skb, struct avc_audit_data *ad)
2865 {
2866 	u8 nexthdr;
2867 	int ret = -EINVAL, offset;
2868 	struct ipv6hdr _ipv6h, *ip6;
2869 
2870 	offset = skb->nh.raw - skb->data;
2871 	ip6 = skb_header_pointer(skb, offset, sizeof(_ipv6h), &_ipv6h);
2872 	if (ip6 == NULL)
2873 		goto out;
2874 
2875 	ipv6_addr_copy(&ad->u.net.v6info.saddr, &ip6->saddr);
2876 	ipv6_addr_copy(&ad->u.net.v6info.daddr, &ip6->daddr);
2877 	ret = 0;
2878 
2879 	nexthdr = ip6->nexthdr;
2880 	offset += sizeof(_ipv6h);
2881 	offset = ipv6_skip_exthdr(skb, offset, &nexthdr);
2882 	if (offset < 0)
2883 		goto out;
2884 
2885 	switch (nexthdr) {
2886 	case IPPROTO_TCP: {
2887         	struct tcphdr _tcph, *th;
2888 
2889 		th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph);
2890 		if (th == NULL)
2891 			break;
2892 
2893 		ad->u.net.sport = th->source;
2894 		ad->u.net.dport = th->dest;
2895 		break;
2896 	}
2897 
2898 	case IPPROTO_UDP: {
2899 		struct udphdr _udph, *uh;
2900 
2901 		uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph);
2902 		if (uh == NULL)
2903 			break;
2904 
2905 		ad->u.net.sport = uh->source;
2906 		ad->u.net.dport = uh->dest;
2907 		break;
2908 	}
2909 
2910 	/* includes fragments */
2911 	default:
2912 		break;
2913 	}
2914 out:
2915 	return ret;
2916 }
2917 
2918 #endif /* IPV6 */
2919 
2920 static int selinux_parse_skb(struct sk_buff *skb, struct avc_audit_data *ad,
2921 			     char **addrp, int *len, int src)
2922 {
2923 	int ret = 0;
2924 
2925 	switch (ad->u.net.family) {
2926 	case PF_INET:
2927 		ret = selinux_parse_skb_ipv4(skb, ad);
2928 		if (ret || !addrp)
2929 			break;
2930 		*len = 4;
2931 		*addrp = (char *)(src ? &ad->u.net.v4info.saddr :
2932 					&ad->u.net.v4info.daddr);
2933 		break;
2934 
2935 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
2936 	case PF_INET6:
2937 		ret = selinux_parse_skb_ipv6(skb, ad);
2938 		if (ret || !addrp)
2939 			break;
2940 		*len = 16;
2941 		*addrp = (char *)(src ? &ad->u.net.v6info.saddr :
2942 					&ad->u.net.v6info.daddr);
2943 		break;
2944 #endif	/* IPV6 */
2945 	default:
2946 		break;
2947 	}
2948 
2949 	return ret;
2950 }
2951 
2952 /* socket security operations */
2953 static int socket_has_perm(struct task_struct *task, struct socket *sock,
2954 			   u32 perms)
2955 {
2956 	struct inode_security_struct *isec;
2957 	struct task_security_struct *tsec;
2958 	struct avc_audit_data ad;
2959 	int err = 0;
2960 
2961 	tsec = task->security;
2962 	isec = SOCK_INODE(sock)->i_security;
2963 
2964 	if (isec->sid == SECINITSID_KERNEL)
2965 		goto out;
2966 
2967 	AVC_AUDIT_DATA_INIT(&ad,NET);
2968 	ad.u.net.sk = sock->sk;
2969 	err = avc_has_perm(tsec->sid, isec->sid, isec->sclass, perms, &ad);
2970 
2971 out:
2972 	return err;
2973 }
2974 
2975 static int selinux_socket_create(int family, int type,
2976 				 int protocol, int kern)
2977 {
2978 	int err = 0;
2979 	struct task_security_struct *tsec;
2980 
2981 	if (kern)
2982 		goto out;
2983 
2984 	tsec = current->security;
2985 	err = avc_has_perm(tsec->sid, tsec->sid,
2986 			   socket_type_to_security_class(family, type,
2987 			   protocol), SOCKET__CREATE, NULL);
2988 
2989 out:
2990 	return err;
2991 }
2992 
2993 static void selinux_socket_post_create(struct socket *sock, int family,
2994 				       int type, int protocol, int kern)
2995 {
2996 	struct inode_security_struct *isec;
2997 	struct task_security_struct *tsec;
2998 
2999 	isec = SOCK_INODE(sock)->i_security;
3000 
3001 	tsec = current->security;
3002 	isec->sclass = socket_type_to_security_class(family, type, protocol);
3003 	isec->sid = kern ? SECINITSID_KERNEL : tsec->sid;
3004 	isec->initialized = 1;
3005 
3006 	return;
3007 }
3008 
3009 /* Range of port numbers used to automatically bind.
3010    Need to determine whether we should perform a name_bind
3011    permission check between the socket and the port number. */
3012 #define ip_local_port_range_0 sysctl_local_port_range[0]
3013 #define ip_local_port_range_1 sysctl_local_port_range[1]
3014 
3015 static int selinux_socket_bind(struct socket *sock, struct sockaddr *address, int addrlen)
3016 {
3017 	u16 family;
3018 	int err;
3019 
3020 	err = socket_has_perm(current, sock, SOCKET__BIND);
3021 	if (err)
3022 		goto out;
3023 
3024 	/*
3025 	 * If PF_INET or PF_INET6, check name_bind permission for the port.
3026 	 */
3027 	family = sock->sk->sk_family;
3028 	if (family == PF_INET || family == PF_INET6) {
3029 		char *addrp;
3030 		struct inode_security_struct *isec;
3031 		struct task_security_struct *tsec;
3032 		struct avc_audit_data ad;
3033 		struct sockaddr_in *addr4 = NULL;
3034 		struct sockaddr_in6 *addr6 = NULL;
3035 		unsigned short snum;
3036 		struct sock *sk = sock->sk;
3037 		u32 sid, node_perm, addrlen;
3038 
3039 		tsec = current->security;
3040 		isec = SOCK_INODE(sock)->i_security;
3041 
3042 		if (family == PF_INET) {
3043 			addr4 = (struct sockaddr_in *)address;
3044 			snum = ntohs(addr4->sin_port);
3045 			addrlen = sizeof(addr4->sin_addr.s_addr);
3046 			addrp = (char *)&addr4->sin_addr.s_addr;
3047 		} else {
3048 			addr6 = (struct sockaddr_in6 *)address;
3049 			snum = ntohs(addr6->sin6_port);
3050 			addrlen = sizeof(addr6->sin6_addr.s6_addr);
3051 			addrp = (char *)&addr6->sin6_addr.s6_addr;
3052 		}
3053 
3054 		if (snum&&(snum < max(PROT_SOCK,ip_local_port_range_0) ||
3055 			   snum > ip_local_port_range_1)) {
3056 			err = security_port_sid(sk->sk_family, sk->sk_type,
3057 						sk->sk_protocol, snum, &sid);
3058 			if (err)
3059 				goto out;
3060 			AVC_AUDIT_DATA_INIT(&ad,NET);
3061 			ad.u.net.sport = htons(snum);
3062 			ad.u.net.family = family;
3063 			err = avc_has_perm(isec->sid, sid,
3064 					   isec->sclass,
3065 					   SOCKET__NAME_BIND, &ad);
3066 			if (err)
3067 				goto out;
3068 		}
3069 
3070 		switch(sk->sk_protocol) {
3071 		case IPPROTO_TCP:
3072 			node_perm = TCP_SOCKET__NODE_BIND;
3073 			break;
3074 
3075 		case IPPROTO_UDP:
3076 			node_perm = UDP_SOCKET__NODE_BIND;
3077 			break;
3078 
3079 		default:
3080 			node_perm = RAWIP_SOCKET__NODE_BIND;
3081 			break;
3082 		}
3083 
3084 		err = security_node_sid(family, addrp, addrlen, &sid);
3085 		if (err)
3086 			goto out;
3087 
3088 		AVC_AUDIT_DATA_INIT(&ad,NET);
3089 		ad.u.net.sport = htons(snum);
3090 		ad.u.net.family = family;
3091 
3092 		if (family == PF_INET)
3093 			ad.u.net.v4info.saddr = addr4->sin_addr.s_addr;
3094 		else
3095 			ipv6_addr_copy(&ad.u.net.v6info.saddr, &addr6->sin6_addr);
3096 
3097 		err = avc_has_perm(isec->sid, sid,
3098 		                   isec->sclass, node_perm, &ad);
3099 		if (err)
3100 			goto out;
3101 	}
3102 out:
3103 	return err;
3104 }
3105 
3106 static int selinux_socket_connect(struct socket *sock, struct sockaddr *address, int addrlen)
3107 {
3108 	struct inode_security_struct *isec;
3109 	int err;
3110 
3111 	err = socket_has_perm(current, sock, SOCKET__CONNECT);
3112 	if (err)
3113 		return err;
3114 
3115 	/*
3116 	 * If a TCP socket, check name_connect permission for the port.
3117 	 */
3118 	isec = SOCK_INODE(sock)->i_security;
3119 	if (isec->sclass == SECCLASS_TCP_SOCKET) {
3120 		struct sock *sk = sock->sk;
3121 		struct avc_audit_data ad;
3122 		struct sockaddr_in *addr4 = NULL;
3123 		struct sockaddr_in6 *addr6 = NULL;
3124 		unsigned short snum;
3125 		u32 sid;
3126 
3127 		if (sk->sk_family == PF_INET) {
3128 			addr4 = (struct sockaddr_in *)address;
3129 			if (addrlen < sizeof(struct sockaddr_in))
3130 				return -EINVAL;
3131 			snum = ntohs(addr4->sin_port);
3132 		} else {
3133 			addr6 = (struct sockaddr_in6 *)address;
3134 			if (addrlen < SIN6_LEN_RFC2133)
3135 				return -EINVAL;
3136 			snum = ntohs(addr6->sin6_port);
3137 		}
3138 
3139 		err = security_port_sid(sk->sk_family, sk->sk_type,
3140 					sk->sk_protocol, snum, &sid);
3141 		if (err)
3142 			goto out;
3143 
3144 		AVC_AUDIT_DATA_INIT(&ad,NET);
3145 		ad.u.net.dport = htons(snum);
3146 		ad.u.net.family = sk->sk_family;
3147 		err = avc_has_perm(isec->sid, sid, isec->sclass,
3148 				   TCP_SOCKET__NAME_CONNECT, &ad);
3149 		if (err)
3150 			goto out;
3151 	}
3152 
3153 out:
3154 	return err;
3155 }
3156 
3157 static int selinux_socket_listen(struct socket *sock, int backlog)
3158 {
3159 	return socket_has_perm(current, sock, SOCKET__LISTEN);
3160 }
3161 
3162 static int selinux_socket_accept(struct socket *sock, struct socket *newsock)
3163 {
3164 	int err;
3165 	struct inode_security_struct *isec;
3166 	struct inode_security_struct *newisec;
3167 
3168 	err = socket_has_perm(current, sock, SOCKET__ACCEPT);
3169 	if (err)
3170 		return err;
3171 
3172 	newisec = SOCK_INODE(newsock)->i_security;
3173 
3174 	isec = SOCK_INODE(sock)->i_security;
3175 	newisec->sclass = isec->sclass;
3176 	newisec->sid = isec->sid;
3177 	newisec->initialized = 1;
3178 
3179 	return 0;
3180 }
3181 
3182 static int selinux_socket_sendmsg(struct socket *sock, struct msghdr *msg,
3183  				  int size)
3184 {
3185 	return socket_has_perm(current, sock, SOCKET__WRITE);
3186 }
3187 
3188 static int selinux_socket_recvmsg(struct socket *sock, struct msghdr *msg,
3189 				  int size, int flags)
3190 {
3191 	return socket_has_perm(current, sock, SOCKET__READ);
3192 }
3193 
3194 static int selinux_socket_getsockname(struct socket *sock)
3195 {
3196 	return socket_has_perm(current, sock, SOCKET__GETATTR);
3197 }
3198 
3199 static int selinux_socket_getpeername(struct socket *sock)
3200 {
3201 	return socket_has_perm(current, sock, SOCKET__GETATTR);
3202 }
3203 
3204 static int selinux_socket_setsockopt(struct socket *sock,int level,int optname)
3205 {
3206 	return socket_has_perm(current, sock, SOCKET__SETOPT);
3207 }
3208 
3209 static int selinux_socket_getsockopt(struct socket *sock, int level,
3210 				     int optname)
3211 {
3212 	return socket_has_perm(current, sock, SOCKET__GETOPT);
3213 }
3214 
3215 static int selinux_socket_shutdown(struct socket *sock, int how)
3216 {
3217 	return socket_has_perm(current, sock, SOCKET__SHUTDOWN);
3218 }
3219 
3220 static int selinux_socket_unix_stream_connect(struct socket *sock,
3221 					      struct socket *other,
3222 					      struct sock *newsk)
3223 {
3224 	struct sk_security_struct *ssec;
3225 	struct inode_security_struct *isec;
3226 	struct inode_security_struct *other_isec;
3227 	struct avc_audit_data ad;
3228 	int err;
3229 
3230 	err = secondary_ops->unix_stream_connect(sock, other, newsk);
3231 	if (err)
3232 		return err;
3233 
3234 	isec = SOCK_INODE(sock)->i_security;
3235 	other_isec = SOCK_INODE(other)->i_security;
3236 
3237 	AVC_AUDIT_DATA_INIT(&ad,NET);
3238 	ad.u.net.sk = other->sk;
3239 
3240 	err = avc_has_perm(isec->sid, other_isec->sid,
3241 			   isec->sclass,
3242 			   UNIX_STREAM_SOCKET__CONNECTTO, &ad);
3243 	if (err)
3244 		return err;
3245 
3246 	/* connecting socket */
3247 	ssec = sock->sk->sk_security;
3248 	ssec->peer_sid = other_isec->sid;
3249 
3250 	/* server child socket */
3251 	ssec = newsk->sk_security;
3252 	ssec->peer_sid = isec->sid;
3253 
3254 	return 0;
3255 }
3256 
3257 static int selinux_socket_unix_may_send(struct socket *sock,
3258 					struct socket *other)
3259 {
3260 	struct inode_security_struct *isec;
3261 	struct inode_security_struct *other_isec;
3262 	struct avc_audit_data ad;
3263 	int err;
3264 
3265 	isec = SOCK_INODE(sock)->i_security;
3266 	other_isec = SOCK_INODE(other)->i_security;
3267 
3268 	AVC_AUDIT_DATA_INIT(&ad,NET);
3269 	ad.u.net.sk = other->sk;
3270 
3271 	err = avc_has_perm(isec->sid, other_isec->sid,
3272 			   isec->sclass, SOCKET__SENDTO, &ad);
3273 	if (err)
3274 		return err;
3275 
3276 	return 0;
3277 }
3278 
3279 static int selinux_socket_sock_rcv_skb(struct sock *sk, struct sk_buff *skb)
3280 {
3281 	u16 family;
3282 	char *addrp;
3283 	int len, err = 0;
3284 	u32 netif_perm, node_perm, node_sid, if_sid, recv_perm = 0;
3285 	u32 sock_sid = 0;
3286 	u16 sock_class = 0;
3287 	struct socket *sock;
3288 	struct net_device *dev;
3289 	struct avc_audit_data ad;
3290 
3291 	family = sk->sk_family;
3292 	if (family != PF_INET && family != PF_INET6)
3293 		goto out;
3294 
3295 	/* Handle mapped IPv4 packets arriving via IPv6 sockets */
3296 	if (family == PF_INET6 && skb->protocol == ntohs(ETH_P_IP))
3297 		family = PF_INET;
3298 
3299  	read_lock_bh(&sk->sk_callback_lock);
3300  	sock = sk->sk_socket;
3301  	if (sock) {
3302  		struct inode *inode;
3303  		inode = SOCK_INODE(sock);
3304  		if (inode) {
3305  			struct inode_security_struct *isec;
3306  			isec = inode->i_security;
3307  			sock_sid = isec->sid;
3308  			sock_class = isec->sclass;
3309  		}
3310  	}
3311  	read_unlock_bh(&sk->sk_callback_lock);
3312  	if (!sock_sid)
3313   		goto out;
3314 
3315 	dev = skb->dev;
3316 	if (!dev)
3317 		goto out;
3318 
3319 	err = sel_netif_sids(dev, &if_sid, NULL);
3320 	if (err)
3321 		goto out;
3322 
3323 	switch (sock_class) {
3324 	case SECCLASS_UDP_SOCKET:
3325 		netif_perm = NETIF__UDP_RECV;
3326 		node_perm = NODE__UDP_RECV;
3327 		recv_perm = UDP_SOCKET__RECV_MSG;
3328 		break;
3329 
3330 	case SECCLASS_TCP_SOCKET:
3331 		netif_perm = NETIF__TCP_RECV;
3332 		node_perm = NODE__TCP_RECV;
3333 		recv_perm = TCP_SOCKET__RECV_MSG;
3334 		break;
3335 
3336 	default:
3337 		netif_perm = NETIF__RAWIP_RECV;
3338 		node_perm = NODE__RAWIP_RECV;
3339 		break;
3340 	}
3341 
3342 	AVC_AUDIT_DATA_INIT(&ad, NET);
3343 	ad.u.net.netif = dev->name;
3344 	ad.u.net.family = family;
3345 
3346 	err = selinux_parse_skb(skb, &ad, &addrp, &len, 1);
3347 	if (err)
3348 		goto out;
3349 
3350 	err = avc_has_perm(sock_sid, if_sid, SECCLASS_NETIF, netif_perm, &ad);
3351 	if (err)
3352 		goto out;
3353 
3354 	/* Fixme: this lookup is inefficient */
3355 	err = security_node_sid(family, addrp, len, &node_sid);
3356 	if (err)
3357 		goto out;
3358 
3359 	err = avc_has_perm(sock_sid, node_sid, SECCLASS_NODE, node_perm, &ad);
3360 	if (err)
3361 		goto out;
3362 
3363 	if (recv_perm) {
3364 		u32 port_sid;
3365 
3366 		/* Fixme: make this more efficient */
3367 		err = security_port_sid(sk->sk_family, sk->sk_type,
3368 		                        sk->sk_protocol, ntohs(ad.u.net.sport),
3369 		                        &port_sid);
3370 		if (err)
3371 			goto out;
3372 
3373 		err = avc_has_perm(sock_sid, port_sid,
3374 				   sock_class, recv_perm, &ad);
3375 	}
3376 out:
3377 	return err;
3378 }
3379 
3380 static int selinux_socket_getpeersec(struct socket *sock, char __user *optval,
3381 				     int __user *optlen, unsigned len)
3382 {
3383 	int err = 0;
3384 	char *scontext;
3385 	u32 scontext_len;
3386 	struct sk_security_struct *ssec;
3387 	struct inode_security_struct *isec;
3388 
3389 	isec = SOCK_INODE(sock)->i_security;
3390 	if (isec->sclass != SECCLASS_UNIX_STREAM_SOCKET) {
3391 		err = -ENOPROTOOPT;
3392 		goto out;
3393 	}
3394 
3395 	ssec = sock->sk->sk_security;
3396 
3397 	err = security_sid_to_context(ssec->peer_sid, &scontext, &scontext_len);
3398 	if (err)
3399 		goto out;
3400 
3401 	if (scontext_len > len) {
3402 		err = -ERANGE;
3403 		goto out_len;
3404 	}
3405 
3406 	if (copy_to_user(optval, scontext, scontext_len))
3407 		err = -EFAULT;
3408 
3409 out_len:
3410 	if (put_user(scontext_len, optlen))
3411 		err = -EFAULT;
3412 
3413 	kfree(scontext);
3414 out:
3415 	return err;
3416 }
3417 
3418 static int selinux_sk_alloc_security(struct sock *sk, int family, int priority)
3419 {
3420 	return sk_alloc_security(sk, family, priority);
3421 }
3422 
3423 static void selinux_sk_free_security(struct sock *sk)
3424 {
3425 	sk_free_security(sk);
3426 }
3427 
3428 static int selinux_nlmsg_perm(struct sock *sk, struct sk_buff *skb)
3429 {
3430 	int err = 0;
3431 	u32 perm;
3432 	struct nlmsghdr *nlh;
3433 	struct socket *sock = sk->sk_socket;
3434 	struct inode_security_struct *isec = SOCK_INODE(sock)->i_security;
3435 
3436 	if (skb->len < NLMSG_SPACE(0)) {
3437 		err = -EINVAL;
3438 		goto out;
3439 	}
3440 	nlh = (struct nlmsghdr *)skb->data;
3441 
3442 	err = selinux_nlmsg_lookup(isec->sclass, nlh->nlmsg_type, &perm);
3443 	if (err) {
3444 		if (err == -EINVAL) {
3445 			audit_log(current->audit_context, AUDIT_SELINUX_ERR,
3446 				  "SELinux:  unrecognized netlink message"
3447 				  " type=%hu for sclass=%hu\n",
3448 				  nlh->nlmsg_type, isec->sclass);
3449 			if (!selinux_enforcing)
3450 				err = 0;
3451 		}
3452 
3453 		/* Ignore */
3454 		if (err == -ENOENT)
3455 			err = 0;
3456 		goto out;
3457 	}
3458 
3459 	err = socket_has_perm(current, sock, perm);
3460 out:
3461 	return err;
3462 }
3463 
3464 #ifdef CONFIG_NETFILTER
3465 
3466 static unsigned int selinux_ip_postroute_last(unsigned int hooknum,
3467                                               struct sk_buff **pskb,
3468                                               const struct net_device *in,
3469                                               const struct net_device *out,
3470                                               int (*okfn)(struct sk_buff *),
3471                                               u16 family)
3472 {
3473 	char *addrp;
3474 	int len, err = NF_ACCEPT;
3475 	u32 netif_perm, node_perm, node_sid, if_sid, send_perm = 0;
3476 	struct sock *sk;
3477 	struct socket *sock;
3478 	struct inode *inode;
3479 	struct sk_buff *skb = *pskb;
3480 	struct inode_security_struct *isec;
3481 	struct avc_audit_data ad;
3482 	struct net_device *dev = (struct net_device *)out;
3483 
3484 	sk = skb->sk;
3485 	if (!sk)
3486 		goto out;
3487 
3488 	sock = sk->sk_socket;
3489 	if (!sock)
3490 		goto out;
3491 
3492 	inode = SOCK_INODE(sock);
3493 	if (!inode)
3494 		goto out;
3495 
3496 	err = sel_netif_sids(dev, &if_sid, NULL);
3497 	if (err)
3498 		goto out;
3499 
3500 	isec = inode->i_security;
3501 
3502 	switch (isec->sclass) {
3503 	case SECCLASS_UDP_SOCKET:
3504 		netif_perm = NETIF__UDP_SEND;
3505 		node_perm = NODE__UDP_SEND;
3506 		send_perm = UDP_SOCKET__SEND_MSG;
3507 		break;
3508 
3509 	case SECCLASS_TCP_SOCKET:
3510 		netif_perm = NETIF__TCP_SEND;
3511 		node_perm = NODE__TCP_SEND;
3512 		send_perm = TCP_SOCKET__SEND_MSG;
3513 		break;
3514 
3515 	default:
3516 		netif_perm = NETIF__RAWIP_SEND;
3517 		node_perm = NODE__RAWIP_SEND;
3518 		break;
3519 	}
3520 
3521 
3522 	AVC_AUDIT_DATA_INIT(&ad, NET);
3523 	ad.u.net.netif = dev->name;
3524 	ad.u.net.family = family;
3525 
3526 	err = selinux_parse_skb(skb, &ad, &addrp,
3527 				&len, 0) ? NF_DROP : NF_ACCEPT;
3528 	if (err != NF_ACCEPT)
3529 		goto out;
3530 
3531 	err = avc_has_perm(isec->sid, if_sid, SECCLASS_NETIF,
3532 	                   netif_perm, &ad) ? NF_DROP : NF_ACCEPT;
3533 	if (err != NF_ACCEPT)
3534 		goto out;
3535 
3536 	/* Fixme: this lookup is inefficient */
3537 	err = security_node_sid(family, addrp, len,
3538 				&node_sid) ? NF_DROP : NF_ACCEPT;
3539 	if (err != NF_ACCEPT)
3540 		goto out;
3541 
3542 	err = avc_has_perm(isec->sid, node_sid, SECCLASS_NODE,
3543 	                   node_perm, &ad) ? NF_DROP : NF_ACCEPT;
3544 	if (err != NF_ACCEPT)
3545 		goto out;
3546 
3547 	if (send_perm) {
3548 		u32 port_sid;
3549 
3550 		/* Fixme: make this more efficient */
3551 		err = security_port_sid(sk->sk_family,
3552 		                        sk->sk_type,
3553 		                        sk->sk_protocol,
3554 		                        ntohs(ad.u.net.dport),
3555 		                        &port_sid) ? NF_DROP : NF_ACCEPT;
3556 		if (err != NF_ACCEPT)
3557 			goto out;
3558 
3559 		err = avc_has_perm(isec->sid, port_sid, isec->sclass,
3560 		                   send_perm, &ad) ? NF_DROP : NF_ACCEPT;
3561 	}
3562 
3563 out:
3564 	return err;
3565 }
3566 
3567 static unsigned int selinux_ipv4_postroute_last(unsigned int hooknum,
3568 						struct sk_buff **pskb,
3569 						const struct net_device *in,
3570 						const struct net_device *out,
3571 						int (*okfn)(struct sk_buff *))
3572 {
3573 	return selinux_ip_postroute_last(hooknum, pskb, in, out, okfn, PF_INET);
3574 }
3575 
3576 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
3577 
3578 static unsigned int selinux_ipv6_postroute_last(unsigned int hooknum,
3579 						struct sk_buff **pskb,
3580 						const struct net_device *in,
3581 						const struct net_device *out,
3582 						int (*okfn)(struct sk_buff *))
3583 {
3584 	return selinux_ip_postroute_last(hooknum, pskb, in, out, okfn, PF_INET6);
3585 }
3586 
3587 #endif	/* IPV6 */
3588 
3589 #endif	/* CONFIG_NETFILTER */
3590 
3591 #else
3592 
3593 static inline int selinux_nlmsg_perm(struct sock *sk, struct sk_buff *skb)
3594 {
3595 	return 0;
3596 }
3597 
3598 #endif	/* CONFIG_SECURITY_NETWORK */
3599 
3600 static int selinux_netlink_send(struct sock *sk, struct sk_buff *skb)
3601 {
3602 	struct task_security_struct *tsec;
3603 	struct av_decision avd;
3604 	int err;
3605 
3606 	err = secondary_ops->netlink_send(sk, skb);
3607 	if (err)
3608 		return err;
3609 
3610 	tsec = current->security;
3611 
3612 	avd.allowed = 0;
3613 	avc_has_perm_noaudit(tsec->sid, tsec->sid,
3614 				SECCLASS_CAPABILITY, ~0, &avd);
3615 	cap_mask(NETLINK_CB(skb).eff_cap, avd.allowed);
3616 
3617 	if (policydb_loaded_version >= POLICYDB_VERSION_NLCLASS)
3618 		err = selinux_nlmsg_perm(sk, skb);
3619 
3620 	return err;
3621 }
3622 
3623 static int selinux_netlink_recv(struct sk_buff *skb)
3624 {
3625 	if (!cap_raised(NETLINK_CB(skb).eff_cap, CAP_NET_ADMIN))
3626 		return -EPERM;
3627 	return 0;
3628 }
3629 
3630 static int ipc_alloc_security(struct task_struct *task,
3631 			      struct kern_ipc_perm *perm,
3632 			      u16 sclass)
3633 {
3634 	struct task_security_struct *tsec = task->security;
3635 	struct ipc_security_struct *isec;
3636 
3637 	isec = kmalloc(sizeof(struct ipc_security_struct), GFP_KERNEL);
3638 	if (!isec)
3639 		return -ENOMEM;
3640 
3641 	memset(isec, 0, sizeof(struct ipc_security_struct));
3642 	isec->magic = SELINUX_MAGIC;
3643 	isec->sclass = sclass;
3644 	isec->ipc_perm = perm;
3645 	if (tsec) {
3646 		isec->sid = tsec->sid;
3647 	} else {
3648 		isec->sid = SECINITSID_UNLABELED;
3649 	}
3650 	perm->security = isec;
3651 
3652 	return 0;
3653 }
3654 
3655 static void ipc_free_security(struct kern_ipc_perm *perm)
3656 {
3657 	struct ipc_security_struct *isec = perm->security;
3658 	if (!isec || isec->magic != SELINUX_MAGIC)
3659 		return;
3660 
3661 	perm->security = NULL;
3662 	kfree(isec);
3663 }
3664 
3665 static int msg_msg_alloc_security(struct msg_msg *msg)
3666 {
3667 	struct msg_security_struct *msec;
3668 
3669 	msec = kmalloc(sizeof(struct msg_security_struct), GFP_KERNEL);
3670 	if (!msec)
3671 		return -ENOMEM;
3672 
3673 	memset(msec, 0, sizeof(struct msg_security_struct));
3674 	msec->magic = SELINUX_MAGIC;
3675 	msec->msg = msg;
3676 	msec->sid = SECINITSID_UNLABELED;
3677 	msg->security = msec;
3678 
3679 	return 0;
3680 }
3681 
3682 static void msg_msg_free_security(struct msg_msg *msg)
3683 {
3684 	struct msg_security_struct *msec = msg->security;
3685 	if (!msec || msec->magic != SELINUX_MAGIC)
3686 		return;
3687 
3688 	msg->security = NULL;
3689 	kfree(msec);
3690 }
3691 
3692 static int ipc_has_perm(struct kern_ipc_perm *ipc_perms,
3693 			u32 perms)
3694 {
3695 	struct task_security_struct *tsec;
3696 	struct ipc_security_struct *isec;
3697 	struct avc_audit_data ad;
3698 
3699 	tsec = current->security;
3700 	isec = ipc_perms->security;
3701 
3702 	AVC_AUDIT_DATA_INIT(&ad, IPC);
3703 	ad.u.ipc_id = ipc_perms->key;
3704 
3705 	return avc_has_perm(tsec->sid, isec->sid, isec->sclass, perms, &ad);
3706 }
3707 
3708 static int selinux_msg_msg_alloc_security(struct msg_msg *msg)
3709 {
3710 	return msg_msg_alloc_security(msg);
3711 }
3712 
3713 static void selinux_msg_msg_free_security(struct msg_msg *msg)
3714 {
3715 	msg_msg_free_security(msg);
3716 }
3717 
3718 /* message queue security operations */
3719 static int selinux_msg_queue_alloc_security(struct msg_queue *msq)
3720 {
3721 	struct task_security_struct *tsec;
3722 	struct ipc_security_struct *isec;
3723 	struct avc_audit_data ad;
3724 	int rc;
3725 
3726 	rc = ipc_alloc_security(current, &msq->q_perm, SECCLASS_MSGQ);
3727 	if (rc)
3728 		return rc;
3729 
3730 	tsec = current->security;
3731 	isec = msq->q_perm.security;
3732 
3733 	AVC_AUDIT_DATA_INIT(&ad, IPC);
3734  	ad.u.ipc_id = msq->q_perm.key;
3735 
3736 	rc = avc_has_perm(tsec->sid, isec->sid, SECCLASS_MSGQ,
3737 			  MSGQ__CREATE, &ad);
3738 	if (rc) {
3739 		ipc_free_security(&msq->q_perm);
3740 		return rc;
3741 	}
3742 	return 0;
3743 }
3744 
3745 static void selinux_msg_queue_free_security(struct msg_queue *msq)
3746 {
3747 	ipc_free_security(&msq->q_perm);
3748 }
3749 
3750 static int selinux_msg_queue_associate(struct msg_queue *msq, int msqflg)
3751 {
3752 	struct task_security_struct *tsec;
3753 	struct ipc_security_struct *isec;
3754 	struct avc_audit_data ad;
3755 
3756 	tsec = current->security;
3757 	isec = msq->q_perm.security;
3758 
3759 	AVC_AUDIT_DATA_INIT(&ad, IPC);
3760 	ad.u.ipc_id = msq->q_perm.key;
3761 
3762 	return avc_has_perm(tsec->sid, isec->sid, SECCLASS_MSGQ,
3763 			    MSGQ__ASSOCIATE, &ad);
3764 }
3765 
3766 static int selinux_msg_queue_msgctl(struct msg_queue *msq, int cmd)
3767 {
3768 	int err;
3769 	int perms;
3770 
3771 	switch(cmd) {
3772 	case IPC_INFO:
3773 	case MSG_INFO:
3774 		/* No specific object, just general system-wide information. */
3775 		return task_has_system(current, SYSTEM__IPC_INFO);
3776 	case IPC_STAT:
3777 	case MSG_STAT:
3778 		perms = MSGQ__GETATTR | MSGQ__ASSOCIATE;
3779 		break;
3780 	case IPC_SET:
3781 		perms = MSGQ__SETATTR;
3782 		break;
3783 	case IPC_RMID:
3784 		perms = MSGQ__DESTROY;
3785 		break;
3786 	default:
3787 		return 0;
3788 	}
3789 
3790 	err = ipc_has_perm(&msq->q_perm, perms);
3791 	return err;
3792 }
3793 
3794 static int selinux_msg_queue_msgsnd(struct msg_queue *msq, struct msg_msg *msg, int msqflg)
3795 {
3796 	struct task_security_struct *tsec;
3797 	struct ipc_security_struct *isec;
3798 	struct msg_security_struct *msec;
3799 	struct avc_audit_data ad;
3800 	int rc;
3801 
3802 	tsec = current->security;
3803 	isec = msq->q_perm.security;
3804 	msec = msg->security;
3805 
3806 	/*
3807 	 * First time through, need to assign label to the message
3808 	 */
3809 	if (msec->sid == SECINITSID_UNLABELED) {
3810 		/*
3811 		 * Compute new sid based on current process and
3812 		 * message queue this message will be stored in
3813 		 */
3814 		rc = security_transition_sid(tsec->sid,
3815 					     isec->sid,
3816 					     SECCLASS_MSG,
3817 					     &msec->sid);
3818 		if (rc)
3819 			return rc;
3820 	}
3821 
3822 	AVC_AUDIT_DATA_INIT(&ad, IPC);
3823 	ad.u.ipc_id = msq->q_perm.key;
3824 
3825 	/* Can this process write to the queue? */
3826 	rc = avc_has_perm(tsec->sid, isec->sid, SECCLASS_MSGQ,
3827 			  MSGQ__WRITE, &ad);
3828 	if (!rc)
3829 		/* Can this process send the message */
3830 		rc = avc_has_perm(tsec->sid, msec->sid,
3831 				  SECCLASS_MSG, MSG__SEND, &ad);
3832 	if (!rc)
3833 		/* Can the message be put in the queue? */
3834 		rc = avc_has_perm(msec->sid, isec->sid,
3835 				  SECCLASS_MSGQ, MSGQ__ENQUEUE, &ad);
3836 
3837 	return rc;
3838 }
3839 
3840 static int selinux_msg_queue_msgrcv(struct msg_queue *msq, struct msg_msg *msg,
3841 				    struct task_struct *target,
3842 				    long type, int mode)
3843 {
3844 	struct task_security_struct *tsec;
3845 	struct ipc_security_struct *isec;
3846 	struct msg_security_struct *msec;
3847 	struct avc_audit_data ad;
3848 	int rc;
3849 
3850 	tsec = target->security;
3851 	isec = msq->q_perm.security;
3852 	msec = msg->security;
3853 
3854 	AVC_AUDIT_DATA_INIT(&ad, IPC);
3855  	ad.u.ipc_id = msq->q_perm.key;
3856 
3857 	rc = avc_has_perm(tsec->sid, isec->sid,
3858 			  SECCLASS_MSGQ, MSGQ__READ, &ad);
3859 	if (!rc)
3860 		rc = avc_has_perm(tsec->sid, msec->sid,
3861 				  SECCLASS_MSG, MSG__RECEIVE, &ad);
3862 	return rc;
3863 }
3864 
3865 /* Shared Memory security operations */
3866 static int selinux_shm_alloc_security(struct shmid_kernel *shp)
3867 {
3868 	struct task_security_struct *tsec;
3869 	struct ipc_security_struct *isec;
3870 	struct avc_audit_data ad;
3871 	int rc;
3872 
3873 	rc = ipc_alloc_security(current, &shp->shm_perm, SECCLASS_SHM);
3874 	if (rc)
3875 		return rc;
3876 
3877 	tsec = current->security;
3878 	isec = shp->shm_perm.security;
3879 
3880 	AVC_AUDIT_DATA_INIT(&ad, IPC);
3881  	ad.u.ipc_id = shp->shm_perm.key;
3882 
3883 	rc = avc_has_perm(tsec->sid, isec->sid, SECCLASS_SHM,
3884 			  SHM__CREATE, &ad);
3885 	if (rc) {
3886 		ipc_free_security(&shp->shm_perm);
3887 		return rc;
3888 	}
3889 	return 0;
3890 }
3891 
3892 static void selinux_shm_free_security(struct shmid_kernel *shp)
3893 {
3894 	ipc_free_security(&shp->shm_perm);
3895 }
3896 
3897 static int selinux_shm_associate(struct shmid_kernel *shp, int shmflg)
3898 {
3899 	struct task_security_struct *tsec;
3900 	struct ipc_security_struct *isec;
3901 	struct avc_audit_data ad;
3902 
3903 	tsec = current->security;
3904 	isec = shp->shm_perm.security;
3905 
3906 	AVC_AUDIT_DATA_INIT(&ad, IPC);
3907 	ad.u.ipc_id = shp->shm_perm.key;
3908 
3909 	return avc_has_perm(tsec->sid, isec->sid, SECCLASS_SHM,
3910 			    SHM__ASSOCIATE, &ad);
3911 }
3912 
3913 /* Note, at this point, shp is locked down */
3914 static int selinux_shm_shmctl(struct shmid_kernel *shp, int cmd)
3915 {
3916 	int perms;
3917 	int err;
3918 
3919 	switch(cmd) {
3920 	case IPC_INFO:
3921 	case SHM_INFO:
3922 		/* No specific object, just general system-wide information. */
3923 		return task_has_system(current, SYSTEM__IPC_INFO);
3924 	case IPC_STAT:
3925 	case SHM_STAT:
3926 		perms = SHM__GETATTR | SHM__ASSOCIATE;
3927 		break;
3928 	case IPC_SET:
3929 		perms = SHM__SETATTR;
3930 		break;
3931 	case SHM_LOCK:
3932 	case SHM_UNLOCK:
3933 		perms = SHM__LOCK;
3934 		break;
3935 	case IPC_RMID:
3936 		perms = SHM__DESTROY;
3937 		break;
3938 	default:
3939 		return 0;
3940 	}
3941 
3942 	err = ipc_has_perm(&shp->shm_perm, perms);
3943 	return err;
3944 }
3945 
3946 static int selinux_shm_shmat(struct shmid_kernel *shp,
3947 			     char __user *shmaddr, int shmflg)
3948 {
3949 	u32 perms;
3950 	int rc;
3951 
3952 	rc = secondary_ops->shm_shmat(shp, shmaddr, shmflg);
3953 	if (rc)
3954 		return rc;
3955 
3956 	if (shmflg & SHM_RDONLY)
3957 		perms = SHM__READ;
3958 	else
3959 		perms = SHM__READ | SHM__WRITE;
3960 
3961 	return ipc_has_perm(&shp->shm_perm, perms);
3962 }
3963 
3964 /* Semaphore security operations */
3965 static int selinux_sem_alloc_security(struct sem_array *sma)
3966 {
3967 	struct task_security_struct *tsec;
3968 	struct ipc_security_struct *isec;
3969 	struct avc_audit_data ad;
3970 	int rc;
3971 
3972 	rc = ipc_alloc_security(current, &sma->sem_perm, SECCLASS_SEM);
3973 	if (rc)
3974 		return rc;
3975 
3976 	tsec = current->security;
3977 	isec = sma->sem_perm.security;
3978 
3979 	AVC_AUDIT_DATA_INIT(&ad, IPC);
3980  	ad.u.ipc_id = sma->sem_perm.key;
3981 
3982 	rc = avc_has_perm(tsec->sid, isec->sid, SECCLASS_SEM,
3983 			  SEM__CREATE, &ad);
3984 	if (rc) {
3985 		ipc_free_security(&sma->sem_perm);
3986 		return rc;
3987 	}
3988 	return 0;
3989 }
3990 
3991 static void selinux_sem_free_security(struct sem_array *sma)
3992 {
3993 	ipc_free_security(&sma->sem_perm);
3994 }
3995 
3996 static int selinux_sem_associate(struct sem_array *sma, int semflg)
3997 {
3998 	struct task_security_struct *tsec;
3999 	struct ipc_security_struct *isec;
4000 	struct avc_audit_data ad;
4001 
4002 	tsec = current->security;
4003 	isec = sma->sem_perm.security;
4004 
4005 	AVC_AUDIT_DATA_INIT(&ad, IPC);
4006 	ad.u.ipc_id = sma->sem_perm.key;
4007 
4008 	return avc_has_perm(tsec->sid, isec->sid, SECCLASS_SEM,
4009 			    SEM__ASSOCIATE, &ad);
4010 }
4011 
4012 /* Note, at this point, sma is locked down */
4013 static int selinux_sem_semctl(struct sem_array *sma, int cmd)
4014 {
4015 	int err;
4016 	u32 perms;
4017 
4018 	switch(cmd) {
4019 	case IPC_INFO:
4020 	case SEM_INFO:
4021 		/* No specific object, just general system-wide information. */
4022 		return task_has_system(current, SYSTEM__IPC_INFO);
4023 	case GETPID:
4024 	case GETNCNT:
4025 	case GETZCNT:
4026 		perms = SEM__GETATTR;
4027 		break;
4028 	case GETVAL:
4029 	case GETALL:
4030 		perms = SEM__READ;
4031 		break;
4032 	case SETVAL:
4033 	case SETALL:
4034 		perms = SEM__WRITE;
4035 		break;
4036 	case IPC_RMID:
4037 		perms = SEM__DESTROY;
4038 		break;
4039 	case IPC_SET:
4040 		perms = SEM__SETATTR;
4041 		break;
4042 	case IPC_STAT:
4043 	case SEM_STAT:
4044 		perms = SEM__GETATTR | SEM__ASSOCIATE;
4045 		break;
4046 	default:
4047 		return 0;
4048 	}
4049 
4050 	err = ipc_has_perm(&sma->sem_perm, perms);
4051 	return err;
4052 }
4053 
4054 static int selinux_sem_semop(struct sem_array *sma,
4055 			     struct sembuf *sops, unsigned nsops, int alter)
4056 {
4057 	u32 perms;
4058 
4059 	if (alter)
4060 		perms = SEM__READ | SEM__WRITE;
4061 	else
4062 		perms = SEM__READ;
4063 
4064 	return ipc_has_perm(&sma->sem_perm, perms);
4065 }
4066 
4067 static int selinux_ipc_permission(struct kern_ipc_perm *ipcp, short flag)
4068 {
4069 	u32 av = 0;
4070 
4071 	av = 0;
4072 	if (flag & S_IRUGO)
4073 		av |= IPC__UNIX_READ;
4074 	if (flag & S_IWUGO)
4075 		av |= IPC__UNIX_WRITE;
4076 
4077 	if (av == 0)
4078 		return 0;
4079 
4080 	return ipc_has_perm(ipcp, av);
4081 }
4082 
4083 /* module stacking operations */
4084 static int selinux_register_security (const char *name, struct security_operations *ops)
4085 {
4086 	if (secondary_ops != original_ops) {
4087 		printk(KERN_INFO "%s:  There is already a secondary security "
4088 		       "module registered.\n", __FUNCTION__);
4089 		return -EINVAL;
4090  	}
4091 
4092 	secondary_ops = ops;
4093 
4094 	printk(KERN_INFO "%s:  Registering secondary module %s\n",
4095 	       __FUNCTION__,
4096 	       name);
4097 
4098 	return 0;
4099 }
4100 
4101 static int selinux_unregister_security (const char *name, struct security_operations *ops)
4102 {
4103 	if (ops != secondary_ops) {
4104 		printk (KERN_INFO "%s:  trying to unregister a security module "
4105 		        "that is not registered.\n", __FUNCTION__);
4106 		return -EINVAL;
4107 	}
4108 
4109 	secondary_ops = original_ops;
4110 
4111 	return 0;
4112 }
4113 
4114 static void selinux_d_instantiate (struct dentry *dentry, struct inode *inode)
4115 {
4116 	if (inode)
4117 		inode_doinit_with_dentry(inode, dentry);
4118 }
4119 
4120 static int selinux_getprocattr(struct task_struct *p,
4121 			       char *name, void *value, size_t size)
4122 {
4123 	struct task_security_struct *tsec;
4124 	u32 sid, len;
4125 	char *context;
4126 	int error;
4127 
4128 	if (current != p) {
4129 		error = task_has_perm(current, p, PROCESS__GETATTR);
4130 		if (error)
4131 			return error;
4132 	}
4133 
4134 	if (!size)
4135 		return -ERANGE;
4136 
4137 	tsec = p->security;
4138 
4139 	if (!strcmp(name, "current"))
4140 		sid = tsec->sid;
4141 	else if (!strcmp(name, "prev"))
4142 		sid = tsec->osid;
4143 	else if (!strcmp(name, "exec"))
4144 		sid = tsec->exec_sid;
4145 	else if (!strcmp(name, "fscreate"))
4146 		sid = tsec->create_sid;
4147 	else
4148 		return -EINVAL;
4149 
4150 	if (!sid)
4151 		return 0;
4152 
4153 	error = security_sid_to_context(sid, &context, &len);
4154 	if (error)
4155 		return error;
4156 	if (len > size) {
4157 		kfree(context);
4158 		return -ERANGE;
4159 	}
4160 	memcpy(value, context, len);
4161 	kfree(context);
4162 	return len;
4163 }
4164 
4165 static int selinux_setprocattr(struct task_struct *p,
4166 			       char *name, void *value, size_t size)
4167 {
4168 	struct task_security_struct *tsec;
4169 	u32 sid = 0;
4170 	int error;
4171 	char *str = value;
4172 
4173 	if (current != p) {
4174 		/* SELinux only allows a process to change its own
4175 		   security attributes. */
4176 		return -EACCES;
4177 	}
4178 
4179 	/*
4180 	 * Basic control over ability to set these attributes at all.
4181 	 * current == p, but we'll pass them separately in case the
4182 	 * above restriction is ever removed.
4183 	 */
4184 	if (!strcmp(name, "exec"))
4185 		error = task_has_perm(current, p, PROCESS__SETEXEC);
4186 	else if (!strcmp(name, "fscreate"))
4187 		error = task_has_perm(current, p, PROCESS__SETFSCREATE);
4188 	else if (!strcmp(name, "current"))
4189 		error = task_has_perm(current, p, PROCESS__SETCURRENT);
4190 	else
4191 		error = -EINVAL;
4192 	if (error)
4193 		return error;
4194 
4195 	/* Obtain a SID for the context, if one was specified. */
4196 	if (size && str[1] && str[1] != '\n') {
4197 		if (str[size-1] == '\n') {
4198 			str[size-1] = 0;
4199 			size--;
4200 		}
4201 		error = security_context_to_sid(value, size, &sid);
4202 		if (error)
4203 			return error;
4204 	}
4205 
4206 	/* Permission checking based on the specified context is
4207 	   performed during the actual operation (execve,
4208 	   open/mkdir/...), when we know the full context of the
4209 	   operation.  See selinux_bprm_set_security for the execve
4210 	   checks and may_create for the file creation checks. The
4211 	   operation will then fail if the context is not permitted. */
4212 	tsec = p->security;
4213 	if (!strcmp(name, "exec"))
4214 		tsec->exec_sid = sid;
4215 	else if (!strcmp(name, "fscreate"))
4216 		tsec->create_sid = sid;
4217 	else if (!strcmp(name, "current")) {
4218 		struct av_decision avd;
4219 
4220 		if (sid == 0)
4221 			return -EINVAL;
4222 
4223 		/* Only allow single threaded processes to change context */
4224 		if (atomic_read(&p->mm->mm_users) != 1) {
4225 			struct task_struct *g, *t;
4226 			struct mm_struct *mm = p->mm;
4227 			read_lock(&tasklist_lock);
4228 			do_each_thread(g, t)
4229 				if (t->mm == mm && t != p) {
4230 					read_unlock(&tasklist_lock);
4231 					return -EPERM;
4232 				}
4233 			while_each_thread(g, t);
4234 			read_unlock(&tasklist_lock);
4235                 }
4236 
4237 		/* Check permissions for the transition. */
4238 		error = avc_has_perm(tsec->sid, sid, SECCLASS_PROCESS,
4239 		                     PROCESS__DYNTRANSITION, NULL);
4240 		if (error)
4241 			return error;
4242 
4243 		/* Check for ptracing, and update the task SID if ok.
4244 		   Otherwise, leave SID unchanged and fail. */
4245 		task_lock(p);
4246 		if (p->ptrace & PT_PTRACED) {
4247 			error = avc_has_perm_noaudit(tsec->ptrace_sid, sid,
4248 						     SECCLASS_PROCESS,
4249 						     PROCESS__PTRACE, &avd);
4250 			if (!error)
4251 				tsec->sid = sid;
4252 			task_unlock(p);
4253 			avc_audit(tsec->ptrace_sid, sid, SECCLASS_PROCESS,
4254 				  PROCESS__PTRACE, &avd, error, NULL);
4255 			if (error)
4256 				return error;
4257 		} else {
4258 			tsec->sid = sid;
4259 			task_unlock(p);
4260 		}
4261 	}
4262 	else
4263 		return -EINVAL;
4264 
4265 	return size;
4266 }
4267 
4268 static struct security_operations selinux_ops = {
4269 	.ptrace =			selinux_ptrace,
4270 	.capget =			selinux_capget,
4271 	.capset_check =			selinux_capset_check,
4272 	.capset_set =			selinux_capset_set,
4273 	.sysctl =			selinux_sysctl,
4274 	.capable =			selinux_capable,
4275 	.quotactl =			selinux_quotactl,
4276 	.quota_on =			selinux_quota_on,
4277 	.syslog =			selinux_syslog,
4278 	.vm_enough_memory =		selinux_vm_enough_memory,
4279 
4280 	.netlink_send =			selinux_netlink_send,
4281         .netlink_recv =			selinux_netlink_recv,
4282 
4283 	.bprm_alloc_security =		selinux_bprm_alloc_security,
4284 	.bprm_free_security =		selinux_bprm_free_security,
4285 	.bprm_apply_creds =		selinux_bprm_apply_creds,
4286 	.bprm_post_apply_creds =	selinux_bprm_post_apply_creds,
4287 	.bprm_set_security =		selinux_bprm_set_security,
4288 	.bprm_check_security =		selinux_bprm_check_security,
4289 	.bprm_secureexec =		selinux_bprm_secureexec,
4290 
4291 	.sb_alloc_security =		selinux_sb_alloc_security,
4292 	.sb_free_security =		selinux_sb_free_security,
4293 	.sb_copy_data =			selinux_sb_copy_data,
4294 	.sb_kern_mount =	        selinux_sb_kern_mount,
4295 	.sb_statfs =			selinux_sb_statfs,
4296 	.sb_mount =			selinux_mount,
4297 	.sb_umount =			selinux_umount,
4298 
4299 	.inode_alloc_security =		selinux_inode_alloc_security,
4300 	.inode_free_security =		selinux_inode_free_security,
4301 	.inode_create =			selinux_inode_create,
4302 	.inode_post_create =		selinux_inode_post_create,
4303 	.inode_link =			selinux_inode_link,
4304 	.inode_post_link =		selinux_inode_post_link,
4305 	.inode_unlink =			selinux_inode_unlink,
4306 	.inode_symlink =		selinux_inode_symlink,
4307 	.inode_post_symlink =		selinux_inode_post_symlink,
4308 	.inode_mkdir =			selinux_inode_mkdir,
4309 	.inode_post_mkdir =		selinux_inode_post_mkdir,
4310 	.inode_rmdir =			selinux_inode_rmdir,
4311 	.inode_mknod =			selinux_inode_mknod,
4312 	.inode_post_mknod =		selinux_inode_post_mknod,
4313 	.inode_rename =			selinux_inode_rename,
4314 	.inode_post_rename =		selinux_inode_post_rename,
4315 	.inode_readlink =		selinux_inode_readlink,
4316 	.inode_follow_link =		selinux_inode_follow_link,
4317 	.inode_permission =		selinux_inode_permission,
4318 	.inode_setattr =		selinux_inode_setattr,
4319 	.inode_getattr =		selinux_inode_getattr,
4320 	.inode_setxattr =		selinux_inode_setxattr,
4321 	.inode_post_setxattr =		selinux_inode_post_setxattr,
4322 	.inode_getxattr =		selinux_inode_getxattr,
4323 	.inode_listxattr =		selinux_inode_listxattr,
4324 	.inode_removexattr =		selinux_inode_removexattr,
4325 	.inode_getsecurity =            selinux_inode_getsecurity,
4326 	.inode_setsecurity =            selinux_inode_setsecurity,
4327 	.inode_listsecurity =           selinux_inode_listsecurity,
4328 
4329 	.file_permission =		selinux_file_permission,
4330 	.file_alloc_security =		selinux_file_alloc_security,
4331 	.file_free_security =		selinux_file_free_security,
4332 	.file_ioctl =			selinux_file_ioctl,
4333 	.file_mmap =			selinux_file_mmap,
4334 	.file_mprotect =		selinux_file_mprotect,
4335 	.file_lock =			selinux_file_lock,
4336 	.file_fcntl =			selinux_file_fcntl,
4337 	.file_set_fowner =		selinux_file_set_fowner,
4338 	.file_send_sigiotask =		selinux_file_send_sigiotask,
4339 	.file_receive =			selinux_file_receive,
4340 
4341 	.task_create =			selinux_task_create,
4342 	.task_alloc_security =		selinux_task_alloc_security,
4343 	.task_free_security =		selinux_task_free_security,
4344 	.task_setuid =			selinux_task_setuid,
4345 	.task_post_setuid =		selinux_task_post_setuid,
4346 	.task_setgid =			selinux_task_setgid,
4347 	.task_setpgid =			selinux_task_setpgid,
4348 	.task_getpgid =			selinux_task_getpgid,
4349 	.task_getsid =		        selinux_task_getsid,
4350 	.task_setgroups =		selinux_task_setgroups,
4351 	.task_setnice =			selinux_task_setnice,
4352 	.task_setrlimit =		selinux_task_setrlimit,
4353 	.task_setscheduler =		selinux_task_setscheduler,
4354 	.task_getscheduler =		selinux_task_getscheduler,
4355 	.task_kill =			selinux_task_kill,
4356 	.task_wait =			selinux_task_wait,
4357 	.task_prctl =			selinux_task_prctl,
4358 	.task_reparent_to_init =	selinux_task_reparent_to_init,
4359 	.task_to_inode =                selinux_task_to_inode,
4360 
4361 	.ipc_permission =		selinux_ipc_permission,
4362 
4363 	.msg_msg_alloc_security =	selinux_msg_msg_alloc_security,
4364 	.msg_msg_free_security =	selinux_msg_msg_free_security,
4365 
4366 	.msg_queue_alloc_security =	selinux_msg_queue_alloc_security,
4367 	.msg_queue_free_security =	selinux_msg_queue_free_security,
4368 	.msg_queue_associate =		selinux_msg_queue_associate,
4369 	.msg_queue_msgctl =		selinux_msg_queue_msgctl,
4370 	.msg_queue_msgsnd =		selinux_msg_queue_msgsnd,
4371 	.msg_queue_msgrcv =		selinux_msg_queue_msgrcv,
4372 
4373 	.shm_alloc_security =		selinux_shm_alloc_security,
4374 	.shm_free_security =		selinux_shm_free_security,
4375 	.shm_associate =		selinux_shm_associate,
4376 	.shm_shmctl =			selinux_shm_shmctl,
4377 	.shm_shmat =			selinux_shm_shmat,
4378 
4379 	.sem_alloc_security = 		selinux_sem_alloc_security,
4380 	.sem_free_security =  		selinux_sem_free_security,
4381 	.sem_associate =		selinux_sem_associate,
4382 	.sem_semctl =			selinux_sem_semctl,
4383 	.sem_semop =			selinux_sem_semop,
4384 
4385 	.register_security =		selinux_register_security,
4386 	.unregister_security =		selinux_unregister_security,
4387 
4388 	.d_instantiate =                selinux_d_instantiate,
4389 
4390 	.getprocattr =                  selinux_getprocattr,
4391 	.setprocattr =                  selinux_setprocattr,
4392 
4393 #ifdef CONFIG_SECURITY_NETWORK
4394         .unix_stream_connect =		selinux_socket_unix_stream_connect,
4395 	.unix_may_send =		selinux_socket_unix_may_send,
4396 
4397 	.socket_create =		selinux_socket_create,
4398 	.socket_post_create =		selinux_socket_post_create,
4399 	.socket_bind =			selinux_socket_bind,
4400 	.socket_connect =		selinux_socket_connect,
4401 	.socket_listen =		selinux_socket_listen,
4402 	.socket_accept =		selinux_socket_accept,
4403 	.socket_sendmsg =		selinux_socket_sendmsg,
4404 	.socket_recvmsg =		selinux_socket_recvmsg,
4405 	.socket_getsockname =		selinux_socket_getsockname,
4406 	.socket_getpeername =		selinux_socket_getpeername,
4407 	.socket_getsockopt =		selinux_socket_getsockopt,
4408 	.socket_setsockopt =		selinux_socket_setsockopt,
4409 	.socket_shutdown =		selinux_socket_shutdown,
4410 	.socket_sock_rcv_skb =		selinux_socket_sock_rcv_skb,
4411 	.socket_getpeersec =		selinux_socket_getpeersec,
4412 	.sk_alloc_security =		selinux_sk_alloc_security,
4413 	.sk_free_security =		selinux_sk_free_security,
4414 #endif
4415 };
4416 
4417 static __init int selinux_init(void)
4418 {
4419 	struct task_security_struct *tsec;
4420 
4421 	if (!selinux_enabled) {
4422 		printk(KERN_INFO "SELinux:  Disabled at boot.\n");
4423 		return 0;
4424 	}
4425 
4426 	printk(KERN_INFO "SELinux:  Initializing.\n");
4427 
4428 	/* Set the security state for the initial task. */
4429 	if (task_alloc_security(current))
4430 		panic("SELinux:  Failed to initialize initial task.\n");
4431 	tsec = current->security;
4432 	tsec->osid = tsec->sid = SECINITSID_KERNEL;
4433 
4434 	avc_init();
4435 
4436 	original_ops = secondary_ops = security_ops;
4437 	if (!secondary_ops)
4438 		panic ("SELinux: No initial security operations\n");
4439 	if (register_security (&selinux_ops))
4440 		panic("SELinux: Unable to register with kernel.\n");
4441 
4442 	if (selinux_enforcing) {
4443 		printk(KERN_INFO "SELinux:  Starting in enforcing mode\n");
4444 	} else {
4445 		printk(KERN_INFO "SELinux:  Starting in permissive mode\n");
4446 	}
4447 	return 0;
4448 }
4449 
4450 void selinux_complete_init(void)
4451 {
4452 	printk(KERN_INFO "SELinux:  Completing initialization.\n");
4453 
4454 	/* Set up any superblocks initialized prior to the policy load. */
4455 	printk(KERN_INFO "SELinux:  Setting up existing superblocks.\n");
4456 	spin_lock(&sb_security_lock);
4457 next_sb:
4458 	if (!list_empty(&superblock_security_head)) {
4459 		struct superblock_security_struct *sbsec =
4460 				list_entry(superblock_security_head.next,
4461 				           struct superblock_security_struct,
4462 				           list);
4463 		struct super_block *sb = sbsec->sb;
4464 		spin_lock(&sb_lock);
4465 		sb->s_count++;
4466 		spin_unlock(&sb_lock);
4467 		spin_unlock(&sb_security_lock);
4468 		down_read(&sb->s_umount);
4469 		if (sb->s_root)
4470 			superblock_doinit(sb, NULL);
4471 		drop_super(sb);
4472 		spin_lock(&sb_security_lock);
4473 		list_del_init(&sbsec->list);
4474 		goto next_sb;
4475 	}
4476 	spin_unlock(&sb_security_lock);
4477 }
4478 
4479 /* SELinux requires early initialization in order to label
4480    all processes and objects when they are created. */
4481 security_initcall(selinux_init);
4482 
4483 #if defined(CONFIG_SECURITY_NETWORK) && defined(CONFIG_NETFILTER)
4484 
4485 static struct nf_hook_ops selinux_ipv4_op = {
4486 	.hook =		selinux_ipv4_postroute_last,
4487 	.owner =	THIS_MODULE,
4488 	.pf =		PF_INET,
4489 	.hooknum =	NF_IP_POST_ROUTING,
4490 	.priority =	NF_IP_PRI_SELINUX_LAST,
4491 };
4492 
4493 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
4494 
4495 static struct nf_hook_ops selinux_ipv6_op = {
4496 	.hook =		selinux_ipv6_postroute_last,
4497 	.owner =	THIS_MODULE,
4498 	.pf =		PF_INET6,
4499 	.hooknum =	NF_IP6_POST_ROUTING,
4500 	.priority =	NF_IP6_PRI_SELINUX_LAST,
4501 };
4502 
4503 #endif	/* IPV6 */
4504 
4505 static int __init selinux_nf_ip_init(void)
4506 {
4507 	int err = 0;
4508 
4509 	if (!selinux_enabled)
4510 		goto out;
4511 
4512 	printk(KERN_INFO "SELinux:  Registering netfilter hooks\n");
4513 
4514 	err = nf_register_hook(&selinux_ipv4_op);
4515 	if (err)
4516 		panic("SELinux: nf_register_hook for IPv4: error %d\n", err);
4517 
4518 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
4519 
4520 	err = nf_register_hook(&selinux_ipv6_op);
4521 	if (err)
4522 		panic("SELinux: nf_register_hook for IPv6: error %d\n", err);
4523 
4524 #endif	/* IPV6 */
4525 out:
4526 	return err;
4527 }
4528 
4529 __initcall(selinux_nf_ip_init);
4530 
4531 #ifdef CONFIG_SECURITY_SELINUX_DISABLE
4532 static void selinux_nf_ip_exit(void)
4533 {
4534 	printk(KERN_INFO "SELinux:  Unregistering netfilter hooks\n");
4535 
4536 	nf_unregister_hook(&selinux_ipv4_op);
4537 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
4538 	nf_unregister_hook(&selinux_ipv6_op);
4539 #endif	/* IPV6 */
4540 }
4541 #endif
4542 
4543 #else /* CONFIG_SECURITY_NETWORK && CONFIG_NETFILTER */
4544 
4545 #ifdef CONFIG_SECURITY_SELINUX_DISABLE
4546 #define selinux_nf_ip_exit()
4547 #endif
4548 
4549 #endif /* CONFIG_SECURITY_NETWORK && CONFIG_NETFILTER */
4550 
4551 #ifdef CONFIG_SECURITY_SELINUX_DISABLE
4552 int selinux_disable(void)
4553 {
4554 	extern void exit_sel_fs(void);
4555 	static int selinux_disabled = 0;
4556 
4557 	if (ss_initialized) {
4558 		/* Not permitted after initial policy load. */
4559 		return -EINVAL;
4560 	}
4561 
4562 	if (selinux_disabled) {
4563 		/* Only do this once. */
4564 		return -EINVAL;
4565 	}
4566 
4567 	printk(KERN_INFO "SELinux:  Disabled at runtime.\n");
4568 
4569 	selinux_disabled = 1;
4570 
4571 	/* Reset security_ops to the secondary module, dummy or capability. */
4572 	security_ops = secondary_ops;
4573 
4574 	/* Unregister netfilter hooks. */
4575 	selinux_nf_ip_exit();
4576 
4577 	/* Unregister selinuxfs. */
4578 	exit_sel_fs();
4579 
4580 	return 0;
4581 }
4582 #endif
4583 
4584 
4585