xref: /linux/security/selinux/hooks.c (revision 776cfebb430c7b22c208b1b17add97f354d97cab)
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 
72 #include "avc.h"
73 #include "objsec.h"
74 #include "netif.h"
75 
76 #define XATTR_SELINUX_SUFFIX "selinux"
77 #define XATTR_NAME_SELINUX XATTR_SECURITY_PREFIX XATTR_SELINUX_SUFFIX
78 
79 extern unsigned int policydb_loaded_version;
80 extern int selinux_nlmsg_lookup(u16 sclass, u16 nlmsg_type, u32 *perm);
81 
82 #ifdef CONFIG_SECURITY_SELINUX_DEVELOP
83 int selinux_enforcing = 0;
84 
85 static int __init enforcing_setup(char *str)
86 {
87 	selinux_enforcing = simple_strtol(str,NULL,0);
88 	return 1;
89 }
90 __setup("enforcing=", enforcing_setup);
91 #endif
92 
93 #ifdef CONFIG_SECURITY_SELINUX_BOOTPARAM
94 int selinux_enabled = CONFIG_SECURITY_SELINUX_BOOTPARAM_VALUE;
95 
96 static int __init selinux_enabled_setup(char *str)
97 {
98 	selinux_enabled = simple_strtol(str, NULL, 0);
99 	return 1;
100 }
101 __setup("selinux=", selinux_enabled_setup);
102 #endif
103 
104 /* Original (dummy) security module. */
105 static struct security_operations *original_ops = NULL;
106 
107 /* Minimal support for a secondary security module,
108    just to allow the use of the dummy or capability modules.
109    The owlsm module can alternatively be used as a secondary
110    module as long as CONFIG_OWLSM_FD is not enabled. */
111 static struct security_operations *secondary_ops = NULL;
112 
113 /* Lists of inode and superblock security structures initialized
114    before the policy was loaded. */
115 static LIST_HEAD(superblock_security_head);
116 static DEFINE_SPINLOCK(sb_security_lock);
117 
118 /* Allocate and free functions for each kind of security blob. */
119 
120 static int task_alloc_security(struct task_struct *task)
121 {
122 	struct task_security_struct *tsec;
123 
124 	tsec = kmalloc(sizeof(struct task_security_struct), GFP_KERNEL);
125 	if (!tsec)
126 		return -ENOMEM;
127 
128 	memset(tsec, 0, sizeof(struct task_security_struct));
129 	tsec->magic = SELINUX_MAGIC;
130 	tsec->task = task;
131 	tsec->osid = tsec->sid = tsec->ptrace_sid = SECINITSID_UNLABELED;
132 	task->security = tsec;
133 
134 	return 0;
135 }
136 
137 static void task_free_security(struct task_struct *task)
138 {
139 	struct task_security_struct *tsec = task->security;
140 
141 	if (!tsec || tsec->magic != SELINUX_MAGIC)
142 		return;
143 
144 	task->security = NULL;
145 	kfree(tsec);
146 }
147 
148 static int inode_alloc_security(struct inode *inode)
149 {
150 	struct task_security_struct *tsec = current->security;
151 	struct inode_security_struct *isec;
152 
153 	isec = kmalloc(sizeof(struct inode_security_struct), GFP_KERNEL);
154 	if (!isec)
155 		return -ENOMEM;
156 
157 	memset(isec, 0, sizeof(struct inode_security_struct));
158 	init_MUTEX(&isec->sem);
159 	INIT_LIST_HEAD(&isec->list);
160 	isec->magic = SELINUX_MAGIC;
161 	isec->inode = inode;
162 	isec->sid = SECINITSID_UNLABELED;
163 	isec->sclass = SECCLASS_FILE;
164 	if (tsec && tsec->magic == SELINUX_MAGIC)
165 		isec->task_sid = tsec->sid;
166 	else
167 		isec->task_sid = SECINITSID_UNLABELED;
168 	inode->i_security = isec;
169 
170 	return 0;
171 }
172 
173 static void inode_free_security(struct inode *inode)
174 {
175 	struct inode_security_struct *isec = inode->i_security;
176 	struct superblock_security_struct *sbsec = inode->i_sb->s_security;
177 
178 	if (!isec || isec->magic != SELINUX_MAGIC)
179 		return;
180 
181 	spin_lock(&sbsec->isec_lock);
182 	if (!list_empty(&isec->list))
183 		list_del_init(&isec->list);
184 	spin_unlock(&sbsec->isec_lock);
185 
186 	inode->i_security = NULL;
187 	kfree(isec);
188 }
189 
190 static int file_alloc_security(struct file *file)
191 {
192 	struct task_security_struct *tsec = current->security;
193 	struct file_security_struct *fsec;
194 
195 	fsec = kmalloc(sizeof(struct file_security_struct), GFP_ATOMIC);
196 	if (!fsec)
197 		return -ENOMEM;
198 
199 	memset(fsec, 0, sizeof(struct file_security_struct));
200 	fsec->magic = SELINUX_MAGIC;
201 	fsec->file = file;
202 	if (tsec && tsec->magic == SELINUX_MAGIC) {
203 		fsec->sid = tsec->sid;
204 		fsec->fown_sid = tsec->sid;
205 	} else {
206 		fsec->sid = SECINITSID_UNLABELED;
207 		fsec->fown_sid = SECINITSID_UNLABELED;
208 	}
209 	file->f_security = fsec;
210 
211 	return 0;
212 }
213 
214 static void file_free_security(struct file *file)
215 {
216 	struct file_security_struct *fsec = file->f_security;
217 
218 	if (!fsec || fsec->magic != SELINUX_MAGIC)
219 		return;
220 
221 	file->f_security = NULL;
222 	kfree(fsec);
223 }
224 
225 static int superblock_alloc_security(struct super_block *sb)
226 {
227 	struct superblock_security_struct *sbsec;
228 
229 	sbsec = kmalloc(sizeof(struct superblock_security_struct), GFP_KERNEL);
230 	if (!sbsec)
231 		return -ENOMEM;
232 
233 	memset(sbsec, 0, sizeof(struct superblock_security_struct));
234 	init_MUTEX(&sbsec->sem);
235 	INIT_LIST_HEAD(&sbsec->list);
236 	INIT_LIST_HEAD(&sbsec->isec_head);
237 	spin_lock_init(&sbsec->isec_lock);
238 	sbsec->magic = SELINUX_MAGIC;
239 	sbsec->sb = sb;
240 	sbsec->sid = SECINITSID_UNLABELED;
241 	sbsec->def_sid = SECINITSID_FILE;
242 	sb->s_security = sbsec;
243 
244 	return 0;
245 }
246 
247 static void superblock_free_security(struct super_block *sb)
248 {
249 	struct superblock_security_struct *sbsec = sb->s_security;
250 
251 	if (!sbsec || sbsec->magic != SELINUX_MAGIC)
252 		return;
253 
254 	spin_lock(&sb_security_lock);
255 	if (!list_empty(&sbsec->list))
256 		list_del_init(&sbsec->list);
257 	spin_unlock(&sb_security_lock);
258 
259 	sb->s_security = NULL;
260 	kfree(sbsec);
261 }
262 
263 #ifdef CONFIG_SECURITY_NETWORK
264 static int sk_alloc_security(struct sock *sk, int family, int priority)
265 {
266 	struct sk_security_struct *ssec;
267 
268 	if (family != PF_UNIX)
269 		return 0;
270 
271 	ssec = kmalloc(sizeof(*ssec), priority);
272 	if (!ssec)
273 		return -ENOMEM;
274 
275 	memset(ssec, 0, sizeof(*ssec));
276 	ssec->magic = SELINUX_MAGIC;
277 	ssec->sk = sk;
278 	ssec->peer_sid = SECINITSID_UNLABELED;
279 	sk->sk_security = ssec;
280 
281 	return 0;
282 }
283 
284 static void sk_free_security(struct sock *sk)
285 {
286 	struct sk_security_struct *ssec = sk->sk_security;
287 
288 	if (sk->sk_family != PF_UNIX || ssec->magic != SELINUX_MAGIC)
289 		return;
290 
291 	sk->sk_security = NULL;
292 	kfree(ssec);
293 }
294 #endif	/* CONFIG_SECURITY_NETWORK */
295 
296 /* The security server must be initialized before
297    any labeling or access decisions can be provided. */
298 extern int ss_initialized;
299 
300 /* The file system's label must be initialized prior to use. */
301 
302 static char *labeling_behaviors[6] = {
303 	"uses xattr",
304 	"uses transition SIDs",
305 	"uses task SIDs",
306 	"uses genfs_contexts",
307 	"not configured for labeling",
308 	"uses mountpoint labeling",
309 };
310 
311 static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dentry);
312 
313 static inline int inode_doinit(struct inode *inode)
314 {
315 	return inode_doinit_with_dentry(inode, NULL);
316 }
317 
318 enum {
319 	Opt_context = 1,
320 	Opt_fscontext = 2,
321 	Opt_defcontext = 4,
322 };
323 
324 static match_table_t tokens = {
325 	{Opt_context, "context=%s"},
326 	{Opt_fscontext, "fscontext=%s"},
327 	{Opt_defcontext, "defcontext=%s"},
328 };
329 
330 #define SEL_MOUNT_FAIL_MSG "SELinux:  duplicate or incompatible mount options\n"
331 
332 static int try_context_mount(struct super_block *sb, void *data)
333 {
334 	char *context = NULL, *defcontext = NULL;
335 	const char *name;
336 	u32 sid;
337 	int alloc = 0, rc = 0, seen = 0;
338 	struct task_security_struct *tsec = current->security;
339 	struct superblock_security_struct *sbsec = sb->s_security;
340 
341 	if (!data)
342 		goto out;
343 
344 	name = sb->s_type->name;
345 
346 	if (sb->s_type->fs_flags & FS_BINARY_MOUNTDATA) {
347 
348 		/* NFS we understand. */
349 		if (!strcmp(name, "nfs")) {
350 			struct nfs_mount_data *d = data;
351 
352 			if (d->version <  NFS_MOUNT_VERSION)
353 				goto out;
354 
355 			if (d->context[0]) {
356 				context = d->context;
357 				seen |= Opt_context;
358 			}
359 		} else
360 			goto out;
361 
362 	} else {
363 		/* Standard string-based options. */
364 		char *p, *options = data;
365 
366 		while ((p = strsep(&options, ",")) != NULL) {
367 			int token;
368 			substring_t args[MAX_OPT_ARGS];
369 
370 			if (!*p)
371 				continue;
372 
373 			token = match_token(p, tokens, args);
374 
375 			switch (token) {
376 			case Opt_context:
377 				if (seen) {
378 					rc = -EINVAL;
379 					printk(KERN_WARNING SEL_MOUNT_FAIL_MSG);
380 					goto out_free;
381 				}
382 				context = match_strdup(&args[0]);
383 				if (!context) {
384 					rc = -ENOMEM;
385 					goto out_free;
386 				}
387 				if (!alloc)
388 					alloc = 1;
389 				seen |= Opt_context;
390 				break;
391 
392 			case Opt_fscontext:
393 				if (seen & (Opt_context|Opt_fscontext)) {
394 					rc = -EINVAL;
395 					printk(KERN_WARNING SEL_MOUNT_FAIL_MSG);
396 					goto out_free;
397 				}
398 				context = match_strdup(&args[0]);
399 				if (!context) {
400 					rc = -ENOMEM;
401 					goto out_free;
402 				}
403 				if (!alloc)
404 					alloc = 1;
405 				seen |= Opt_fscontext;
406 				break;
407 
408 			case Opt_defcontext:
409 				if (sbsec->behavior != SECURITY_FS_USE_XATTR) {
410 					rc = -EINVAL;
411 					printk(KERN_WARNING "SELinux:  "
412 					       "defcontext option is invalid "
413 					       "for this filesystem type\n");
414 					goto out_free;
415 				}
416 				if (seen & (Opt_context|Opt_defcontext)) {
417 					rc = -EINVAL;
418 					printk(KERN_WARNING SEL_MOUNT_FAIL_MSG);
419 					goto out_free;
420 				}
421 				defcontext = match_strdup(&args[0]);
422 				if (!defcontext) {
423 					rc = -ENOMEM;
424 					goto out_free;
425 				}
426 				if (!alloc)
427 					alloc = 1;
428 				seen |= Opt_defcontext;
429 				break;
430 
431 			default:
432 				rc = -EINVAL;
433 				printk(KERN_WARNING "SELinux:  unknown mount "
434 				       "option\n");
435 				goto out_free;
436 
437 			}
438 		}
439 	}
440 
441 	if (!seen)
442 		goto out;
443 
444 	if (context) {
445 		rc = security_context_to_sid(context, strlen(context), &sid);
446 		if (rc) {
447 			printk(KERN_WARNING "SELinux: security_context_to_sid"
448 			       "(%s) failed for (dev %s, type %s) errno=%d\n",
449 			       context, sb->s_id, name, rc);
450 			goto out_free;
451 		}
452 
453 		rc = avc_has_perm(tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM,
454 		                  FILESYSTEM__RELABELFROM, NULL);
455 		if (rc)
456 			goto out_free;
457 
458 		rc = avc_has_perm(tsec->sid, sid, SECCLASS_FILESYSTEM,
459 		                  FILESYSTEM__RELABELTO, NULL);
460 		if (rc)
461 			goto out_free;
462 
463 		sbsec->sid = sid;
464 
465 		if (seen & Opt_context)
466 			sbsec->behavior = SECURITY_FS_USE_MNTPOINT;
467 	}
468 
469 	if (defcontext) {
470 		rc = security_context_to_sid(defcontext, strlen(defcontext), &sid);
471 		if (rc) {
472 			printk(KERN_WARNING "SELinux: security_context_to_sid"
473 			       "(%s) failed for (dev %s, type %s) errno=%d\n",
474 			       defcontext, sb->s_id, name, rc);
475 			goto out_free;
476 		}
477 
478 		if (sid == sbsec->def_sid)
479 			goto out_free;
480 
481 		rc = avc_has_perm(tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM,
482 				  FILESYSTEM__RELABELFROM, NULL);
483 		if (rc)
484 			goto out_free;
485 
486 		rc = avc_has_perm(sid, sbsec->sid, SECCLASS_FILESYSTEM,
487 				  FILESYSTEM__ASSOCIATE, NULL);
488 		if (rc)
489 			goto out_free;
490 
491 		sbsec->def_sid = sid;
492 	}
493 
494 out_free:
495 	if (alloc) {
496 		kfree(context);
497 		kfree(defcontext);
498 	}
499 out:
500 	return rc;
501 }
502 
503 static int superblock_doinit(struct super_block *sb, void *data)
504 {
505 	struct superblock_security_struct *sbsec = sb->s_security;
506 	struct dentry *root = sb->s_root;
507 	struct inode *inode = root->d_inode;
508 	int rc = 0;
509 
510 	down(&sbsec->sem);
511 	if (sbsec->initialized)
512 		goto out;
513 
514 	if (!ss_initialized) {
515 		/* Defer initialization until selinux_complete_init,
516 		   after the initial policy is loaded and the security
517 		   server is ready to handle calls. */
518 		spin_lock(&sb_security_lock);
519 		if (list_empty(&sbsec->list))
520 			list_add(&sbsec->list, &superblock_security_head);
521 		spin_unlock(&sb_security_lock);
522 		goto out;
523 	}
524 
525 	/* Determine the labeling behavior to use for this filesystem type. */
526 	rc = security_fs_use(sb->s_type->name, &sbsec->behavior, &sbsec->sid);
527 	if (rc) {
528 		printk(KERN_WARNING "%s:  security_fs_use(%s) returned %d\n",
529 		       __FUNCTION__, sb->s_type->name, rc);
530 		goto out;
531 	}
532 
533 	rc = try_context_mount(sb, data);
534 	if (rc)
535 		goto out;
536 
537 	if (sbsec->behavior == SECURITY_FS_USE_XATTR) {
538 		/* Make sure that the xattr handler exists and that no
539 		   error other than -ENODATA is returned by getxattr on
540 		   the root directory.  -ENODATA is ok, as this may be
541 		   the first boot of the SELinux kernel before we have
542 		   assigned xattr values to the filesystem. */
543 		if (!inode->i_op->getxattr) {
544 			printk(KERN_WARNING "SELinux: (dev %s, type %s) has no "
545 			       "xattr support\n", sb->s_id, sb->s_type->name);
546 			rc = -EOPNOTSUPP;
547 			goto out;
548 		}
549 		rc = inode->i_op->getxattr(root, XATTR_NAME_SELINUX, NULL, 0);
550 		if (rc < 0 && rc != -ENODATA) {
551 			if (rc == -EOPNOTSUPP)
552 				printk(KERN_WARNING "SELinux: (dev %s, type "
553 				       "%s) has no security xattr handler\n",
554 				       sb->s_id, sb->s_type->name);
555 			else
556 				printk(KERN_WARNING "SELinux: (dev %s, type "
557 				       "%s) getxattr errno %d\n", sb->s_id,
558 				       sb->s_type->name, -rc);
559 			goto out;
560 		}
561 	}
562 
563 	if (strcmp(sb->s_type->name, "proc") == 0)
564 		sbsec->proc = 1;
565 
566 	sbsec->initialized = 1;
567 
568 	if (sbsec->behavior > ARRAY_SIZE(labeling_behaviors)) {
569 		printk(KERN_INFO "SELinux: initialized (dev %s, type %s), unknown behavior\n",
570 		       sb->s_id, sb->s_type->name);
571 	}
572 	else {
573 		printk(KERN_INFO "SELinux: initialized (dev %s, type %s), %s\n",
574 		       sb->s_id, sb->s_type->name,
575 		       labeling_behaviors[sbsec->behavior-1]);
576 	}
577 
578 	/* Initialize the root inode. */
579 	rc = inode_doinit_with_dentry(sb->s_root->d_inode, sb->s_root);
580 
581 	/* Initialize any other inodes associated with the superblock, e.g.
582 	   inodes created prior to initial policy load or inodes created
583 	   during get_sb by a pseudo filesystem that directly
584 	   populates itself. */
585 	spin_lock(&sbsec->isec_lock);
586 next_inode:
587 	if (!list_empty(&sbsec->isec_head)) {
588 		struct inode_security_struct *isec =
589 				list_entry(sbsec->isec_head.next,
590 				           struct inode_security_struct, list);
591 		struct inode *inode = isec->inode;
592 		spin_unlock(&sbsec->isec_lock);
593 		inode = igrab(inode);
594 		if (inode) {
595 			if (!IS_PRIVATE (inode))
596 				inode_doinit(inode);
597 			iput(inode);
598 		}
599 		spin_lock(&sbsec->isec_lock);
600 		list_del_init(&isec->list);
601 		goto next_inode;
602 	}
603 	spin_unlock(&sbsec->isec_lock);
604 out:
605 	up(&sbsec->sem);
606 	return rc;
607 }
608 
609 static inline u16 inode_mode_to_security_class(umode_t mode)
610 {
611 	switch (mode & S_IFMT) {
612 	case S_IFSOCK:
613 		return SECCLASS_SOCK_FILE;
614 	case S_IFLNK:
615 		return SECCLASS_LNK_FILE;
616 	case S_IFREG:
617 		return SECCLASS_FILE;
618 	case S_IFBLK:
619 		return SECCLASS_BLK_FILE;
620 	case S_IFDIR:
621 		return SECCLASS_DIR;
622 	case S_IFCHR:
623 		return SECCLASS_CHR_FILE;
624 	case S_IFIFO:
625 		return SECCLASS_FIFO_FILE;
626 
627 	}
628 
629 	return SECCLASS_FILE;
630 }
631 
632 static inline u16 socket_type_to_security_class(int family, int type, int protocol)
633 {
634 	switch (family) {
635 	case PF_UNIX:
636 		switch (type) {
637 		case SOCK_STREAM:
638 		case SOCK_SEQPACKET:
639 			return SECCLASS_UNIX_STREAM_SOCKET;
640 		case SOCK_DGRAM:
641 			return SECCLASS_UNIX_DGRAM_SOCKET;
642 		}
643 		break;
644 	case PF_INET:
645 	case PF_INET6:
646 		switch (type) {
647 		case SOCK_STREAM:
648 			return SECCLASS_TCP_SOCKET;
649 		case SOCK_DGRAM:
650 			return SECCLASS_UDP_SOCKET;
651 		case SOCK_RAW:
652 			return SECCLASS_RAWIP_SOCKET;
653 		}
654 		break;
655 	case PF_NETLINK:
656 		switch (protocol) {
657 		case NETLINK_ROUTE:
658 			return SECCLASS_NETLINK_ROUTE_SOCKET;
659 		case NETLINK_FIREWALL:
660 			return SECCLASS_NETLINK_FIREWALL_SOCKET;
661 		case NETLINK_TCPDIAG:
662 			return SECCLASS_NETLINK_TCPDIAG_SOCKET;
663 		case NETLINK_NFLOG:
664 			return SECCLASS_NETLINK_NFLOG_SOCKET;
665 		case NETLINK_XFRM:
666 			return SECCLASS_NETLINK_XFRM_SOCKET;
667 		case NETLINK_SELINUX:
668 			return SECCLASS_NETLINK_SELINUX_SOCKET;
669 		case NETLINK_AUDIT:
670 			return SECCLASS_NETLINK_AUDIT_SOCKET;
671 		case NETLINK_IP6_FW:
672 			return SECCLASS_NETLINK_IP6FW_SOCKET;
673 		case NETLINK_DNRTMSG:
674 			return SECCLASS_NETLINK_DNRT_SOCKET;
675 		case NETLINK_KOBJECT_UEVENT:
676 			return SECCLASS_NETLINK_KOBJECT_UEVENT_SOCKET;
677 		default:
678 			return SECCLASS_NETLINK_SOCKET;
679 		}
680 	case PF_PACKET:
681 		return SECCLASS_PACKET_SOCKET;
682 	case PF_KEY:
683 		return SECCLASS_KEY_SOCKET;
684 	}
685 
686 	return SECCLASS_SOCKET;
687 }
688 
689 #ifdef CONFIG_PROC_FS
690 static int selinux_proc_get_sid(struct proc_dir_entry *de,
691 				u16 tclass,
692 				u32 *sid)
693 {
694 	int buflen, rc;
695 	char *buffer, *path, *end;
696 
697 	buffer = (char*)__get_free_page(GFP_KERNEL);
698 	if (!buffer)
699 		return -ENOMEM;
700 
701 	buflen = PAGE_SIZE;
702 	end = buffer+buflen;
703 	*--end = '\0';
704 	buflen--;
705 	path = end-1;
706 	*path = '/';
707 	while (de && de != de->parent) {
708 		buflen -= de->namelen + 1;
709 		if (buflen < 0)
710 			break;
711 		end -= de->namelen;
712 		memcpy(end, de->name, de->namelen);
713 		*--end = '/';
714 		path = end;
715 		de = de->parent;
716 	}
717 	rc = security_genfs_sid("proc", path, tclass, sid);
718 	free_page((unsigned long)buffer);
719 	return rc;
720 }
721 #else
722 static int selinux_proc_get_sid(struct proc_dir_entry *de,
723 				u16 tclass,
724 				u32 *sid)
725 {
726 	return -EINVAL;
727 }
728 #endif
729 
730 /* The inode's security attributes must be initialized before first use. */
731 static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dentry)
732 {
733 	struct superblock_security_struct *sbsec = NULL;
734 	struct inode_security_struct *isec = inode->i_security;
735 	u32 sid;
736 	struct dentry *dentry;
737 #define INITCONTEXTLEN 255
738 	char *context = NULL;
739 	unsigned len = 0;
740 	int rc = 0;
741 	int hold_sem = 0;
742 
743 	if (isec->initialized)
744 		goto out;
745 
746 	down(&isec->sem);
747 	hold_sem = 1;
748 	if (isec->initialized)
749 		goto out;
750 
751 	sbsec = inode->i_sb->s_security;
752 	if (!sbsec->initialized) {
753 		/* Defer initialization until selinux_complete_init,
754 		   after the initial policy is loaded and the security
755 		   server is ready to handle calls. */
756 		spin_lock(&sbsec->isec_lock);
757 		if (list_empty(&isec->list))
758 			list_add(&isec->list, &sbsec->isec_head);
759 		spin_unlock(&sbsec->isec_lock);
760 		goto out;
761 	}
762 
763 	switch (sbsec->behavior) {
764 	case SECURITY_FS_USE_XATTR:
765 		if (!inode->i_op->getxattr) {
766 			isec->sid = sbsec->def_sid;
767 			break;
768 		}
769 
770 		/* Need a dentry, since the xattr API requires one.
771 		   Life would be simpler if we could just pass the inode. */
772 		if (opt_dentry) {
773 			/* Called from d_instantiate or d_splice_alias. */
774 			dentry = dget(opt_dentry);
775 		} else {
776 			/* Called from selinux_complete_init, try to find a dentry. */
777 			dentry = d_find_alias(inode);
778 		}
779 		if (!dentry) {
780 			printk(KERN_WARNING "%s:  no dentry for dev=%s "
781 			       "ino=%ld\n", __FUNCTION__, inode->i_sb->s_id,
782 			       inode->i_ino);
783 			goto out;
784 		}
785 
786 		len = INITCONTEXTLEN;
787 		context = kmalloc(len, GFP_KERNEL);
788 		if (!context) {
789 			rc = -ENOMEM;
790 			dput(dentry);
791 			goto out;
792 		}
793 		rc = inode->i_op->getxattr(dentry, XATTR_NAME_SELINUX,
794 					   context, len);
795 		if (rc == -ERANGE) {
796 			/* Need a larger buffer.  Query for the right size. */
797 			rc = inode->i_op->getxattr(dentry, XATTR_NAME_SELINUX,
798 						   NULL, 0);
799 			if (rc < 0) {
800 				dput(dentry);
801 				goto out;
802 			}
803 			kfree(context);
804 			len = rc;
805 			context = kmalloc(len, GFP_KERNEL);
806 			if (!context) {
807 				rc = -ENOMEM;
808 				dput(dentry);
809 				goto out;
810 			}
811 			rc = inode->i_op->getxattr(dentry,
812 						   XATTR_NAME_SELINUX,
813 						   context, len);
814 		}
815 		dput(dentry);
816 		if (rc < 0) {
817 			if (rc != -ENODATA) {
818 				printk(KERN_WARNING "%s:  getxattr returned "
819 				       "%d for dev=%s ino=%ld\n", __FUNCTION__,
820 				       -rc, inode->i_sb->s_id, inode->i_ino);
821 				kfree(context);
822 				goto out;
823 			}
824 			/* Map ENODATA to the default file SID */
825 			sid = sbsec->def_sid;
826 			rc = 0;
827 		} else {
828 			rc = security_context_to_sid(context, rc, &sid);
829 			if (rc) {
830 				printk(KERN_WARNING "%s:  context_to_sid(%s) "
831 				       "returned %d for dev=%s ino=%ld\n",
832 				       __FUNCTION__, context, -rc,
833 				       inode->i_sb->s_id, inode->i_ino);
834 				kfree(context);
835 				/* Leave with the unlabeled SID */
836 				rc = 0;
837 				break;
838 			}
839 		}
840 		kfree(context);
841 		isec->sid = sid;
842 		break;
843 	case SECURITY_FS_USE_TASK:
844 		isec->sid = isec->task_sid;
845 		break;
846 	case SECURITY_FS_USE_TRANS:
847 		/* Default to the fs SID. */
848 		isec->sid = sbsec->sid;
849 
850 		/* Try to obtain a transition SID. */
851 		isec->sclass = inode_mode_to_security_class(inode->i_mode);
852 		rc = security_transition_sid(isec->task_sid,
853 					     sbsec->sid,
854 					     isec->sclass,
855 					     &sid);
856 		if (rc)
857 			goto out;
858 		isec->sid = sid;
859 		break;
860 	default:
861 		/* Default to the fs SID. */
862 		isec->sid = sbsec->sid;
863 
864 		if (sbsec->proc) {
865 			struct proc_inode *proci = PROC_I(inode);
866 			if (proci->pde) {
867 				isec->sclass = inode_mode_to_security_class(inode->i_mode);
868 				rc = selinux_proc_get_sid(proci->pde,
869 							  isec->sclass,
870 							  &sid);
871 				if (rc)
872 					goto out;
873 				isec->sid = sid;
874 			}
875 		}
876 		break;
877 	}
878 
879 	isec->initialized = 1;
880 
881 out:
882 	if (isec->sclass == SECCLASS_FILE)
883 		isec->sclass = inode_mode_to_security_class(inode->i_mode);
884 
885 	if (hold_sem)
886 		up(&isec->sem);
887 	return rc;
888 }
889 
890 /* Convert a Linux signal to an access vector. */
891 static inline u32 signal_to_av(int sig)
892 {
893 	u32 perm = 0;
894 
895 	switch (sig) {
896 	case SIGCHLD:
897 		/* Commonly granted from child to parent. */
898 		perm = PROCESS__SIGCHLD;
899 		break;
900 	case SIGKILL:
901 		/* Cannot be caught or ignored */
902 		perm = PROCESS__SIGKILL;
903 		break;
904 	case SIGSTOP:
905 		/* Cannot be caught or ignored */
906 		perm = PROCESS__SIGSTOP;
907 		break;
908 	default:
909 		/* All other signals. */
910 		perm = PROCESS__SIGNAL;
911 		break;
912 	}
913 
914 	return perm;
915 }
916 
917 /* Check permission betweeen a pair of tasks, e.g. signal checks,
918    fork check, ptrace check, etc. */
919 static int task_has_perm(struct task_struct *tsk1,
920 			 struct task_struct *tsk2,
921 			 u32 perms)
922 {
923 	struct task_security_struct *tsec1, *tsec2;
924 
925 	tsec1 = tsk1->security;
926 	tsec2 = tsk2->security;
927 	return avc_has_perm(tsec1->sid, tsec2->sid,
928 			    SECCLASS_PROCESS, perms, NULL);
929 }
930 
931 /* Check whether a task is allowed to use a capability. */
932 static int task_has_capability(struct task_struct *tsk,
933 			       int cap)
934 {
935 	struct task_security_struct *tsec;
936 	struct avc_audit_data ad;
937 
938 	tsec = tsk->security;
939 
940 	AVC_AUDIT_DATA_INIT(&ad,CAP);
941 	ad.tsk = tsk;
942 	ad.u.cap = cap;
943 
944 	return avc_has_perm(tsec->sid, tsec->sid,
945 			    SECCLASS_CAPABILITY, CAP_TO_MASK(cap), &ad);
946 }
947 
948 /* Check whether a task is allowed to use a system operation. */
949 static int task_has_system(struct task_struct *tsk,
950 			   u32 perms)
951 {
952 	struct task_security_struct *tsec;
953 
954 	tsec = tsk->security;
955 
956 	return avc_has_perm(tsec->sid, SECINITSID_KERNEL,
957 			    SECCLASS_SYSTEM, perms, NULL);
958 }
959 
960 /* Check whether a task has a particular permission to an inode.
961    The 'adp' parameter is optional and allows other audit
962    data to be passed (e.g. the dentry). */
963 static int inode_has_perm(struct task_struct *tsk,
964 			  struct inode *inode,
965 			  u32 perms,
966 			  struct avc_audit_data *adp)
967 {
968 	struct task_security_struct *tsec;
969 	struct inode_security_struct *isec;
970 	struct avc_audit_data ad;
971 
972 	tsec = tsk->security;
973 	isec = inode->i_security;
974 
975 	if (!adp) {
976 		adp = &ad;
977 		AVC_AUDIT_DATA_INIT(&ad, FS);
978 		ad.u.fs.inode = inode;
979 	}
980 
981 	return avc_has_perm(tsec->sid, isec->sid, isec->sclass, perms, adp);
982 }
983 
984 /* Same as inode_has_perm, but pass explicit audit data containing
985    the dentry to help the auditing code to more easily generate the
986    pathname if needed. */
987 static inline int dentry_has_perm(struct task_struct *tsk,
988 				  struct vfsmount *mnt,
989 				  struct dentry *dentry,
990 				  u32 av)
991 {
992 	struct inode *inode = dentry->d_inode;
993 	struct avc_audit_data ad;
994 	AVC_AUDIT_DATA_INIT(&ad,FS);
995 	ad.u.fs.mnt = mnt;
996 	ad.u.fs.dentry = dentry;
997 	return inode_has_perm(tsk, inode, av, &ad);
998 }
999 
1000 /* Check whether a task can use an open file descriptor to
1001    access an inode in a given way.  Check access to the
1002    descriptor itself, and then use dentry_has_perm to
1003    check a particular permission to the file.
1004    Access to the descriptor is implicitly granted if it
1005    has the same SID as the process.  If av is zero, then
1006    access to the file is not checked, e.g. for cases
1007    where only the descriptor is affected like seek. */
1008 static inline int file_has_perm(struct task_struct *tsk,
1009 				struct file *file,
1010 				u32 av)
1011 {
1012 	struct task_security_struct *tsec = tsk->security;
1013 	struct file_security_struct *fsec = file->f_security;
1014 	struct vfsmount *mnt = file->f_vfsmnt;
1015 	struct dentry *dentry = file->f_dentry;
1016 	struct inode *inode = dentry->d_inode;
1017 	struct avc_audit_data ad;
1018 	int rc;
1019 
1020 	AVC_AUDIT_DATA_INIT(&ad, FS);
1021 	ad.u.fs.mnt = mnt;
1022 	ad.u.fs.dentry = dentry;
1023 
1024 	if (tsec->sid != fsec->sid) {
1025 		rc = avc_has_perm(tsec->sid, fsec->sid,
1026 				  SECCLASS_FD,
1027 				  FD__USE,
1028 				  &ad);
1029 		if (rc)
1030 			return rc;
1031 	}
1032 
1033 	/* av is zero if only checking access to the descriptor. */
1034 	if (av)
1035 		return inode_has_perm(tsk, inode, av, &ad);
1036 
1037 	return 0;
1038 }
1039 
1040 /* Check whether a task can create a file. */
1041 static int may_create(struct inode *dir,
1042 		      struct dentry *dentry,
1043 		      u16 tclass)
1044 {
1045 	struct task_security_struct *tsec;
1046 	struct inode_security_struct *dsec;
1047 	struct superblock_security_struct *sbsec;
1048 	u32 newsid;
1049 	struct avc_audit_data ad;
1050 	int rc;
1051 
1052 	tsec = current->security;
1053 	dsec = dir->i_security;
1054 	sbsec = dir->i_sb->s_security;
1055 
1056 	AVC_AUDIT_DATA_INIT(&ad, FS);
1057 	ad.u.fs.dentry = dentry;
1058 
1059 	rc = avc_has_perm(tsec->sid, dsec->sid, SECCLASS_DIR,
1060 			  DIR__ADD_NAME | DIR__SEARCH,
1061 			  &ad);
1062 	if (rc)
1063 		return rc;
1064 
1065 	if (tsec->create_sid && sbsec->behavior != SECURITY_FS_USE_MNTPOINT) {
1066 		newsid = tsec->create_sid;
1067 	} else {
1068 		rc = security_transition_sid(tsec->sid, dsec->sid, tclass,
1069 					     &newsid);
1070 		if (rc)
1071 			return rc;
1072 	}
1073 
1074 	rc = avc_has_perm(tsec->sid, newsid, tclass, FILE__CREATE, &ad);
1075 	if (rc)
1076 		return rc;
1077 
1078 	return avc_has_perm(newsid, sbsec->sid,
1079 			    SECCLASS_FILESYSTEM,
1080 			    FILESYSTEM__ASSOCIATE, &ad);
1081 }
1082 
1083 #define MAY_LINK   0
1084 #define MAY_UNLINK 1
1085 #define MAY_RMDIR  2
1086 
1087 /* Check whether a task can link, unlink, or rmdir a file/directory. */
1088 static int may_link(struct inode *dir,
1089 		    struct dentry *dentry,
1090 		    int kind)
1091 
1092 {
1093 	struct task_security_struct *tsec;
1094 	struct inode_security_struct *dsec, *isec;
1095 	struct avc_audit_data ad;
1096 	u32 av;
1097 	int rc;
1098 
1099 	tsec = current->security;
1100 	dsec = dir->i_security;
1101 	isec = dentry->d_inode->i_security;
1102 
1103 	AVC_AUDIT_DATA_INIT(&ad, FS);
1104 	ad.u.fs.dentry = dentry;
1105 
1106 	av = DIR__SEARCH;
1107 	av |= (kind ? DIR__REMOVE_NAME : DIR__ADD_NAME);
1108 	rc = avc_has_perm(tsec->sid, dsec->sid, SECCLASS_DIR, av, &ad);
1109 	if (rc)
1110 		return rc;
1111 
1112 	switch (kind) {
1113 	case MAY_LINK:
1114 		av = FILE__LINK;
1115 		break;
1116 	case MAY_UNLINK:
1117 		av = FILE__UNLINK;
1118 		break;
1119 	case MAY_RMDIR:
1120 		av = DIR__RMDIR;
1121 		break;
1122 	default:
1123 		printk(KERN_WARNING "may_link:  unrecognized kind %d\n", kind);
1124 		return 0;
1125 	}
1126 
1127 	rc = avc_has_perm(tsec->sid, isec->sid, isec->sclass, av, &ad);
1128 	return rc;
1129 }
1130 
1131 static inline int may_rename(struct inode *old_dir,
1132 			     struct dentry *old_dentry,
1133 			     struct inode *new_dir,
1134 			     struct dentry *new_dentry)
1135 {
1136 	struct task_security_struct *tsec;
1137 	struct inode_security_struct *old_dsec, *new_dsec, *old_isec, *new_isec;
1138 	struct avc_audit_data ad;
1139 	u32 av;
1140 	int old_is_dir, new_is_dir;
1141 	int rc;
1142 
1143 	tsec = current->security;
1144 	old_dsec = old_dir->i_security;
1145 	old_isec = old_dentry->d_inode->i_security;
1146 	old_is_dir = S_ISDIR(old_dentry->d_inode->i_mode);
1147 	new_dsec = new_dir->i_security;
1148 
1149 	AVC_AUDIT_DATA_INIT(&ad, FS);
1150 
1151 	ad.u.fs.dentry = old_dentry;
1152 	rc = avc_has_perm(tsec->sid, old_dsec->sid, SECCLASS_DIR,
1153 			  DIR__REMOVE_NAME | DIR__SEARCH, &ad);
1154 	if (rc)
1155 		return rc;
1156 	rc = avc_has_perm(tsec->sid, old_isec->sid,
1157 			  old_isec->sclass, FILE__RENAME, &ad);
1158 	if (rc)
1159 		return rc;
1160 	if (old_is_dir && new_dir != old_dir) {
1161 		rc = avc_has_perm(tsec->sid, old_isec->sid,
1162 				  old_isec->sclass, DIR__REPARENT, &ad);
1163 		if (rc)
1164 			return rc;
1165 	}
1166 
1167 	ad.u.fs.dentry = new_dentry;
1168 	av = DIR__ADD_NAME | DIR__SEARCH;
1169 	if (new_dentry->d_inode)
1170 		av |= DIR__REMOVE_NAME;
1171 	rc = avc_has_perm(tsec->sid, new_dsec->sid, SECCLASS_DIR, av, &ad);
1172 	if (rc)
1173 		return rc;
1174 	if (new_dentry->d_inode) {
1175 		new_isec = new_dentry->d_inode->i_security;
1176 		new_is_dir = S_ISDIR(new_dentry->d_inode->i_mode);
1177 		rc = avc_has_perm(tsec->sid, new_isec->sid,
1178 				  new_isec->sclass,
1179 				  (new_is_dir ? DIR__RMDIR : FILE__UNLINK), &ad);
1180 		if (rc)
1181 			return rc;
1182 	}
1183 
1184 	return 0;
1185 }
1186 
1187 /* Check whether a task can perform a filesystem operation. */
1188 static int superblock_has_perm(struct task_struct *tsk,
1189 			       struct super_block *sb,
1190 			       u32 perms,
1191 			       struct avc_audit_data *ad)
1192 {
1193 	struct task_security_struct *tsec;
1194 	struct superblock_security_struct *sbsec;
1195 
1196 	tsec = tsk->security;
1197 	sbsec = sb->s_security;
1198 	return avc_has_perm(tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM,
1199 			    perms, ad);
1200 }
1201 
1202 /* Convert a Linux mode and permission mask to an access vector. */
1203 static inline u32 file_mask_to_av(int mode, int mask)
1204 {
1205 	u32 av = 0;
1206 
1207 	if ((mode & S_IFMT) != S_IFDIR) {
1208 		if (mask & MAY_EXEC)
1209 			av |= FILE__EXECUTE;
1210 		if (mask & MAY_READ)
1211 			av |= FILE__READ;
1212 
1213 		if (mask & MAY_APPEND)
1214 			av |= FILE__APPEND;
1215 		else if (mask & MAY_WRITE)
1216 			av |= FILE__WRITE;
1217 
1218 	} else {
1219 		if (mask & MAY_EXEC)
1220 			av |= DIR__SEARCH;
1221 		if (mask & MAY_WRITE)
1222 			av |= DIR__WRITE;
1223 		if (mask & MAY_READ)
1224 			av |= DIR__READ;
1225 	}
1226 
1227 	return av;
1228 }
1229 
1230 /* Convert a Linux file to an access vector. */
1231 static inline u32 file_to_av(struct file *file)
1232 {
1233 	u32 av = 0;
1234 
1235 	if (file->f_mode & FMODE_READ)
1236 		av |= FILE__READ;
1237 	if (file->f_mode & FMODE_WRITE) {
1238 		if (file->f_flags & O_APPEND)
1239 			av |= FILE__APPEND;
1240 		else
1241 			av |= FILE__WRITE;
1242 	}
1243 
1244 	return av;
1245 }
1246 
1247 /* Set an inode's SID to a specified value. */
1248 static int inode_security_set_sid(struct inode *inode, u32 sid)
1249 {
1250 	struct inode_security_struct *isec = inode->i_security;
1251 	struct superblock_security_struct *sbsec = inode->i_sb->s_security;
1252 
1253 	if (!sbsec->initialized) {
1254 		/* Defer initialization to selinux_complete_init. */
1255 		return 0;
1256 	}
1257 
1258 	down(&isec->sem);
1259 	isec->sclass = inode_mode_to_security_class(inode->i_mode);
1260 	isec->sid = sid;
1261 	isec->initialized = 1;
1262 	up(&isec->sem);
1263 	return 0;
1264 }
1265 
1266 /* Set the security attributes on a newly created file. */
1267 static int post_create(struct inode *dir,
1268 		       struct dentry *dentry)
1269 {
1270 
1271 	struct task_security_struct *tsec;
1272 	struct inode *inode;
1273 	struct inode_security_struct *dsec;
1274 	struct superblock_security_struct *sbsec;
1275 	u32 newsid;
1276 	char *context;
1277 	unsigned int len;
1278 	int rc;
1279 
1280 	tsec = current->security;
1281 	dsec = dir->i_security;
1282 	sbsec = dir->i_sb->s_security;
1283 
1284 	inode = dentry->d_inode;
1285 	if (!inode) {
1286 		/* Some file system types (e.g. NFS) may not instantiate
1287 		   a dentry for all create operations (e.g. symlink),
1288 		   so we have to check to see if the inode is non-NULL. */
1289 		printk(KERN_WARNING "post_create:  no inode, dir (dev=%s, "
1290 		       "ino=%ld)\n", dir->i_sb->s_id, dir->i_ino);
1291 		return 0;
1292 	}
1293 
1294 	if (tsec->create_sid && sbsec->behavior != SECURITY_FS_USE_MNTPOINT) {
1295 		newsid = tsec->create_sid;
1296 	} else {
1297 		rc = security_transition_sid(tsec->sid, dsec->sid,
1298 					     inode_mode_to_security_class(inode->i_mode),
1299 					     &newsid);
1300 		if (rc) {
1301 			printk(KERN_WARNING "post_create:  "
1302 			       "security_transition_sid failed, rc=%d (dev=%s "
1303 			       "ino=%ld)\n",
1304 			       -rc, inode->i_sb->s_id, inode->i_ino);
1305 			return rc;
1306 		}
1307 	}
1308 
1309 	rc = inode_security_set_sid(inode, newsid);
1310 	if (rc) {
1311 		printk(KERN_WARNING "post_create:  inode_security_set_sid "
1312 		       "failed, rc=%d (dev=%s ino=%ld)\n",
1313 		       -rc, inode->i_sb->s_id, inode->i_ino);
1314 		return rc;
1315 	}
1316 
1317 	if (sbsec->behavior == SECURITY_FS_USE_XATTR &&
1318 	    inode->i_op->setxattr) {
1319 		/* Use extended attributes. */
1320 		rc = security_sid_to_context(newsid, &context, &len);
1321 		if (rc) {
1322 			printk(KERN_WARNING "post_create:  sid_to_context "
1323 			       "failed, rc=%d (dev=%s ino=%ld)\n",
1324 			       -rc, inode->i_sb->s_id, inode->i_ino);
1325 			return rc;
1326 		}
1327 		down(&inode->i_sem);
1328 		rc = inode->i_op->setxattr(dentry,
1329 					   XATTR_NAME_SELINUX,
1330 					   context, len, 0);
1331 		up(&inode->i_sem);
1332 		kfree(context);
1333 		if (rc < 0) {
1334 			printk(KERN_WARNING "post_create:  setxattr failed, "
1335 			       "rc=%d (dev=%s ino=%ld)\n",
1336 			       -rc, inode->i_sb->s_id, inode->i_ino);
1337 			return rc;
1338 		}
1339 	}
1340 
1341 	return 0;
1342 }
1343 
1344 
1345 /* Hook functions begin here. */
1346 
1347 static int selinux_ptrace(struct task_struct *parent, struct task_struct *child)
1348 {
1349 	struct task_security_struct *psec = parent->security;
1350 	struct task_security_struct *csec = child->security;
1351 	int rc;
1352 
1353 	rc = secondary_ops->ptrace(parent,child);
1354 	if (rc)
1355 		return rc;
1356 
1357 	rc = task_has_perm(parent, child, PROCESS__PTRACE);
1358 	/* Save the SID of the tracing process for later use in apply_creds. */
1359 	if (!rc)
1360 		csec->ptrace_sid = psec->sid;
1361 	return rc;
1362 }
1363 
1364 static int selinux_capget(struct task_struct *target, kernel_cap_t *effective,
1365                           kernel_cap_t *inheritable, kernel_cap_t *permitted)
1366 {
1367 	int error;
1368 
1369 	error = task_has_perm(current, target, PROCESS__GETCAP);
1370 	if (error)
1371 		return error;
1372 
1373 	return secondary_ops->capget(target, effective, inheritable, permitted);
1374 }
1375 
1376 static int selinux_capset_check(struct task_struct *target, kernel_cap_t *effective,
1377                                 kernel_cap_t *inheritable, kernel_cap_t *permitted)
1378 {
1379 	int error;
1380 
1381 	error = secondary_ops->capset_check(target, effective, inheritable, permitted);
1382 	if (error)
1383 		return error;
1384 
1385 	return task_has_perm(current, target, PROCESS__SETCAP);
1386 }
1387 
1388 static void selinux_capset_set(struct task_struct *target, kernel_cap_t *effective,
1389                                kernel_cap_t *inheritable, kernel_cap_t *permitted)
1390 {
1391 	secondary_ops->capset_set(target, effective, inheritable, permitted);
1392 }
1393 
1394 static int selinux_capable(struct task_struct *tsk, int cap)
1395 {
1396 	int rc;
1397 
1398 	rc = secondary_ops->capable(tsk, cap);
1399 	if (rc)
1400 		return rc;
1401 
1402 	return task_has_capability(tsk,cap);
1403 }
1404 
1405 static int selinux_sysctl(ctl_table *table, int op)
1406 {
1407 	int error = 0;
1408 	u32 av;
1409 	struct task_security_struct *tsec;
1410 	u32 tsid;
1411 	int rc;
1412 
1413 	rc = secondary_ops->sysctl(table, op);
1414 	if (rc)
1415 		return rc;
1416 
1417 	tsec = current->security;
1418 
1419 	rc = selinux_proc_get_sid(table->de, (op == 001) ?
1420 	                          SECCLASS_DIR : SECCLASS_FILE, &tsid);
1421 	if (rc) {
1422 		/* Default to the well-defined sysctl SID. */
1423 		tsid = SECINITSID_SYSCTL;
1424 	}
1425 
1426 	/* The op values are "defined" in sysctl.c, thereby creating
1427 	 * a bad coupling between this module and sysctl.c */
1428 	if(op == 001) {
1429 		error = avc_has_perm(tsec->sid, tsid,
1430 				     SECCLASS_DIR, DIR__SEARCH, NULL);
1431 	} else {
1432 		av = 0;
1433 		if (op & 004)
1434 			av |= FILE__READ;
1435 		if (op & 002)
1436 			av |= FILE__WRITE;
1437 		if (av)
1438 			error = avc_has_perm(tsec->sid, tsid,
1439 					     SECCLASS_FILE, av, NULL);
1440         }
1441 
1442 	return error;
1443 }
1444 
1445 static int selinux_quotactl(int cmds, int type, int id, struct super_block *sb)
1446 {
1447 	int rc = 0;
1448 
1449 	if (!sb)
1450 		return 0;
1451 
1452 	switch (cmds) {
1453 		case Q_SYNC:
1454 		case Q_QUOTAON:
1455 		case Q_QUOTAOFF:
1456 	        case Q_SETINFO:
1457 		case Q_SETQUOTA:
1458 			rc = superblock_has_perm(current,
1459 						 sb,
1460 						 FILESYSTEM__QUOTAMOD, NULL);
1461 			break;
1462 	        case Q_GETFMT:
1463 	        case Q_GETINFO:
1464 		case Q_GETQUOTA:
1465 			rc = superblock_has_perm(current,
1466 						 sb,
1467 						 FILESYSTEM__QUOTAGET, NULL);
1468 			break;
1469 		default:
1470 			rc = 0;  /* let the kernel handle invalid cmds */
1471 			break;
1472 	}
1473 	return rc;
1474 }
1475 
1476 static int selinux_quota_on(struct dentry *dentry)
1477 {
1478 	return dentry_has_perm(current, NULL, dentry, FILE__QUOTAON);
1479 }
1480 
1481 static int selinux_syslog(int type)
1482 {
1483 	int rc;
1484 
1485 	rc = secondary_ops->syslog(type);
1486 	if (rc)
1487 		return rc;
1488 
1489 	switch (type) {
1490 		case 3:         /* Read last kernel messages */
1491 		case 10:        /* Return size of the log buffer */
1492 			rc = task_has_system(current, SYSTEM__SYSLOG_READ);
1493 			break;
1494 		case 6:         /* Disable logging to console */
1495 		case 7:         /* Enable logging to console */
1496 		case 8:		/* Set level of messages printed to console */
1497 			rc = task_has_system(current, SYSTEM__SYSLOG_CONSOLE);
1498 			break;
1499 		case 0:         /* Close log */
1500 		case 1:         /* Open log */
1501 		case 2:         /* Read from log */
1502 		case 4:         /* Read/clear last kernel messages */
1503 		case 5:         /* Clear ring buffer */
1504 		default:
1505 			rc = task_has_system(current, SYSTEM__SYSLOG_MOD);
1506 			break;
1507 	}
1508 	return rc;
1509 }
1510 
1511 /*
1512  * Check that a process has enough memory to allocate a new virtual
1513  * mapping. 0 means there is enough memory for the allocation to
1514  * succeed and -ENOMEM implies there is not.
1515  *
1516  * Note that secondary_ops->capable and task_has_perm_noaudit return 0
1517  * if the capability is granted, but __vm_enough_memory requires 1 if
1518  * the capability is granted.
1519  *
1520  * Do not audit the selinux permission check, as this is applied to all
1521  * processes that allocate mappings.
1522  */
1523 static int selinux_vm_enough_memory(long pages)
1524 {
1525 	int rc, cap_sys_admin = 0;
1526 	struct task_security_struct *tsec = current->security;
1527 
1528 	rc = secondary_ops->capable(current, CAP_SYS_ADMIN);
1529 	if (rc == 0)
1530 		rc = avc_has_perm_noaudit(tsec->sid, tsec->sid,
1531 					SECCLASS_CAPABILITY,
1532 					CAP_TO_MASK(CAP_SYS_ADMIN),
1533 					NULL);
1534 
1535 	if (rc == 0)
1536 		cap_sys_admin = 1;
1537 
1538 	return __vm_enough_memory(pages, cap_sys_admin);
1539 }
1540 
1541 /* binprm security operations */
1542 
1543 static int selinux_bprm_alloc_security(struct linux_binprm *bprm)
1544 {
1545 	struct bprm_security_struct *bsec;
1546 
1547 	bsec = kmalloc(sizeof(struct bprm_security_struct), GFP_KERNEL);
1548 	if (!bsec)
1549 		return -ENOMEM;
1550 
1551 	memset(bsec, 0, sizeof *bsec);
1552 	bsec->magic = SELINUX_MAGIC;
1553 	bsec->bprm = bprm;
1554 	bsec->sid = SECINITSID_UNLABELED;
1555 	bsec->set = 0;
1556 
1557 	bprm->security = bsec;
1558 	return 0;
1559 }
1560 
1561 static int selinux_bprm_set_security(struct linux_binprm *bprm)
1562 {
1563 	struct task_security_struct *tsec;
1564 	struct inode *inode = bprm->file->f_dentry->d_inode;
1565 	struct inode_security_struct *isec;
1566 	struct bprm_security_struct *bsec;
1567 	u32 newsid;
1568 	struct avc_audit_data ad;
1569 	int rc;
1570 
1571 	rc = secondary_ops->bprm_set_security(bprm);
1572 	if (rc)
1573 		return rc;
1574 
1575 	bsec = bprm->security;
1576 
1577 	if (bsec->set)
1578 		return 0;
1579 
1580 	tsec = current->security;
1581 	isec = inode->i_security;
1582 
1583 	/* Default to the current task SID. */
1584 	bsec->sid = tsec->sid;
1585 
1586 	/* Reset create SID on execve. */
1587 	tsec->create_sid = 0;
1588 
1589 	if (tsec->exec_sid) {
1590 		newsid = tsec->exec_sid;
1591 		/* Reset exec SID on execve. */
1592 		tsec->exec_sid = 0;
1593 	} else {
1594 		/* Check for a default transition on this program. */
1595 		rc = security_transition_sid(tsec->sid, isec->sid,
1596 		                             SECCLASS_PROCESS, &newsid);
1597 		if (rc)
1598 			return rc;
1599 	}
1600 
1601 	AVC_AUDIT_DATA_INIT(&ad, FS);
1602 	ad.u.fs.mnt = bprm->file->f_vfsmnt;
1603 	ad.u.fs.dentry = bprm->file->f_dentry;
1604 
1605 	if (bprm->file->f_vfsmnt->mnt_flags & MNT_NOSUID)
1606 		newsid = tsec->sid;
1607 
1608         if (tsec->sid == newsid) {
1609 		rc = avc_has_perm(tsec->sid, isec->sid,
1610 				  SECCLASS_FILE, FILE__EXECUTE_NO_TRANS, &ad);
1611 		if (rc)
1612 			return rc;
1613 	} else {
1614 		/* Check permissions for the transition. */
1615 		rc = avc_has_perm(tsec->sid, newsid,
1616 				  SECCLASS_PROCESS, PROCESS__TRANSITION, &ad);
1617 		if (rc)
1618 			return rc;
1619 
1620 		rc = avc_has_perm(newsid, isec->sid,
1621 				  SECCLASS_FILE, FILE__ENTRYPOINT, &ad);
1622 		if (rc)
1623 			return rc;
1624 
1625 		/* Clear any possibly unsafe personality bits on exec: */
1626 		current->personality &= ~PER_CLEAR_ON_SETID;
1627 
1628 		/* Set the security field to the new SID. */
1629 		bsec->sid = newsid;
1630 	}
1631 
1632 	bsec->set = 1;
1633 	return 0;
1634 }
1635 
1636 static int selinux_bprm_check_security (struct linux_binprm *bprm)
1637 {
1638 	return secondary_ops->bprm_check_security(bprm);
1639 }
1640 
1641 
1642 static int selinux_bprm_secureexec (struct linux_binprm *bprm)
1643 {
1644 	struct task_security_struct *tsec = current->security;
1645 	int atsecure = 0;
1646 
1647 	if (tsec->osid != tsec->sid) {
1648 		/* Enable secure mode for SIDs transitions unless
1649 		   the noatsecure permission is granted between
1650 		   the two SIDs, i.e. ahp returns 0. */
1651 		atsecure = avc_has_perm(tsec->osid, tsec->sid,
1652 					 SECCLASS_PROCESS,
1653 					 PROCESS__NOATSECURE, NULL);
1654 	}
1655 
1656 	return (atsecure || secondary_ops->bprm_secureexec(bprm));
1657 }
1658 
1659 static void selinux_bprm_free_security(struct linux_binprm *bprm)
1660 {
1661 	struct bprm_security_struct *bsec = bprm->security;
1662 	bprm->security = NULL;
1663 	kfree(bsec);
1664 }
1665 
1666 extern struct vfsmount *selinuxfs_mount;
1667 extern struct dentry *selinux_null;
1668 
1669 /* Derived from fs/exec.c:flush_old_files. */
1670 static inline void flush_unauthorized_files(struct files_struct * files)
1671 {
1672 	struct avc_audit_data ad;
1673 	struct file *file, *devnull = NULL;
1674 	struct tty_struct *tty = current->signal->tty;
1675 	long j = -1;
1676 
1677 	if (tty) {
1678 		file_list_lock();
1679 		file = list_entry(tty->tty_files.next, typeof(*file), f_list);
1680 		if (file) {
1681 			/* Revalidate access to controlling tty.
1682 			   Use inode_has_perm on the tty inode directly rather
1683 			   than using file_has_perm, as this particular open
1684 			   file may belong to another process and we are only
1685 			   interested in the inode-based check here. */
1686 			struct inode *inode = file->f_dentry->d_inode;
1687 			if (inode_has_perm(current, inode,
1688 					   FILE__READ | FILE__WRITE, NULL)) {
1689 				/* Reset controlling tty. */
1690 				current->signal->tty = NULL;
1691 				current->signal->tty_old_pgrp = 0;
1692 			}
1693 		}
1694 		file_list_unlock();
1695 	}
1696 
1697 	/* Revalidate access to inherited open files. */
1698 
1699 	AVC_AUDIT_DATA_INIT(&ad,FS);
1700 
1701 	spin_lock(&files->file_lock);
1702 	for (;;) {
1703 		unsigned long set, i;
1704 		int fd;
1705 
1706 		j++;
1707 		i = j * __NFDBITS;
1708 		if (i >= files->max_fds || i >= files->max_fdset)
1709 			break;
1710 		set = files->open_fds->fds_bits[j];
1711 		if (!set)
1712 			continue;
1713 		spin_unlock(&files->file_lock);
1714 		for ( ; set ; i++,set >>= 1) {
1715 			if (set & 1) {
1716 				file = fget(i);
1717 				if (!file)
1718 					continue;
1719 				if (file_has_perm(current,
1720 						  file,
1721 						  file_to_av(file))) {
1722 					sys_close(i);
1723 					fd = get_unused_fd();
1724 					if (fd != i) {
1725 						if (fd >= 0)
1726 							put_unused_fd(fd);
1727 						fput(file);
1728 						continue;
1729 					}
1730 					if (devnull) {
1731 						atomic_inc(&devnull->f_count);
1732 					} else {
1733 						devnull = dentry_open(dget(selinux_null), mntget(selinuxfs_mount), O_RDWR);
1734 						if (!devnull) {
1735 							put_unused_fd(fd);
1736 							fput(file);
1737 							continue;
1738 						}
1739 					}
1740 					fd_install(fd, devnull);
1741 				}
1742 				fput(file);
1743 			}
1744 		}
1745 		spin_lock(&files->file_lock);
1746 
1747 	}
1748 	spin_unlock(&files->file_lock);
1749 }
1750 
1751 static void selinux_bprm_apply_creds(struct linux_binprm *bprm, int unsafe)
1752 {
1753 	struct task_security_struct *tsec;
1754 	struct bprm_security_struct *bsec;
1755 	u32 sid;
1756 	int rc;
1757 
1758 	secondary_ops->bprm_apply_creds(bprm, unsafe);
1759 
1760 	tsec = current->security;
1761 
1762 	bsec = bprm->security;
1763 	sid = bsec->sid;
1764 
1765 	tsec->osid = tsec->sid;
1766 	bsec->unsafe = 0;
1767 	if (tsec->sid != sid) {
1768 		/* Check for shared state.  If not ok, leave SID
1769 		   unchanged and kill. */
1770 		if (unsafe & LSM_UNSAFE_SHARE) {
1771 			rc = avc_has_perm(tsec->sid, sid, SECCLASS_PROCESS,
1772 					PROCESS__SHARE, NULL);
1773 			if (rc) {
1774 				bsec->unsafe = 1;
1775 				return;
1776 			}
1777 		}
1778 
1779 		/* Check for ptracing, and update the task SID if ok.
1780 		   Otherwise, leave SID unchanged and kill. */
1781 		if (unsafe & (LSM_UNSAFE_PTRACE | LSM_UNSAFE_PTRACE_CAP)) {
1782 			rc = avc_has_perm(tsec->ptrace_sid, sid,
1783 					  SECCLASS_PROCESS, PROCESS__PTRACE,
1784 					  NULL);
1785 			if (rc) {
1786 				bsec->unsafe = 1;
1787 				return;
1788 			}
1789 		}
1790 		tsec->sid = sid;
1791 	}
1792 }
1793 
1794 /*
1795  * called after apply_creds without the task lock held
1796  */
1797 static void selinux_bprm_post_apply_creds(struct linux_binprm *bprm)
1798 {
1799 	struct task_security_struct *tsec;
1800 	struct rlimit *rlim, *initrlim;
1801 	struct itimerval itimer;
1802 	struct bprm_security_struct *bsec;
1803 	int rc, i;
1804 
1805 	tsec = current->security;
1806 	bsec = bprm->security;
1807 
1808 	if (bsec->unsafe) {
1809 		force_sig_specific(SIGKILL, current);
1810 		return;
1811 	}
1812 	if (tsec->osid == tsec->sid)
1813 		return;
1814 
1815 	/* Close files for which the new task SID is not authorized. */
1816 	flush_unauthorized_files(current->files);
1817 
1818 	/* Check whether the new SID can inherit signal state
1819 	   from the old SID.  If not, clear itimers to avoid
1820 	   subsequent signal generation and flush and unblock
1821 	   signals. This must occur _after_ the task SID has
1822 	  been updated so that any kill done after the flush
1823 	  will be checked against the new SID. */
1824 	rc = avc_has_perm(tsec->osid, tsec->sid, SECCLASS_PROCESS,
1825 			  PROCESS__SIGINH, NULL);
1826 	if (rc) {
1827 		memset(&itimer, 0, sizeof itimer);
1828 		for (i = 0; i < 3; i++)
1829 			do_setitimer(i, &itimer, NULL);
1830 		flush_signals(current);
1831 		spin_lock_irq(&current->sighand->siglock);
1832 		flush_signal_handlers(current, 1);
1833 		sigemptyset(&current->blocked);
1834 		recalc_sigpending();
1835 		spin_unlock_irq(&current->sighand->siglock);
1836 	}
1837 
1838 	/* Check whether the new SID can inherit resource limits
1839 	   from the old SID.  If not, reset all soft limits to
1840 	   the lower of the current task's hard limit and the init
1841 	   task's soft limit.  Note that the setting of hard limits
1842 	   (even to lower them) can be controlled by the setrlimit
1843 	   check. The inclusion of the init task's soft limit into
1844 	   the computation is to avoid resetting soft limits higher
1845 	   than the default soft limit for cases where the default
1846 	   is lower than the hard limit, e.g. RLIMIT_CORE or
1847 	   RLIMIT_STACK.*/
1848 	rc = avc_has_perm(tsec->osid, tsec->sid, SECCLASS_PROCESS,
1849 			  PROCESS__RLIMITINH, NULL);
1850 	if (rc) {
1851 		for (i = 0; i < RLIM_NLIMITS; i++) {
1852 			rlim = current->signal->rlim + i;
1853 			initrlim = init_task.signal->rlim+i;
1854 			rlim->rlim_cur = min(rlim->rlim_max,initrlim->rlim_cur);
1855 		}
1856 		if (current->signal->rlim[RLIMIT_CPU].rlim_cur != RLIM_INFINITY) {
1857 			/*
1858 			 * This will cause RLIMIT_CPU calculations
1859 			 * to be refigured.
1860 			 */
1861 			current->it_prof_expires = jiffies_to_cputime(1);
1862 		}
1863 	}
1864 
1865 	/* Wake up the parent if it is waiting so that it can
1866 	   recheck wait permission to the new task SID. */
1867 	wake_up_interruptible(&current->parent->signal->wait_chldexit);
1868 }
1869 
1870 /* superblock security operations */
1871 
1872 static int selinux_sb_alloc_security(struct super_block *sb)
1873 {
1874 	return superblock_alloc_security(sb);
1875 }
1876 
1877 static void selinux_sb_free_security(struct super_block *sb)
1878 {
1879 	superblock_free_security(sb);
1880 }
1881 
1882 static inline int match_prefix(char *prefix, int plen, char *option, int olen)
1883 {
1884 	if (plen > olen)
1885 		return 0;
1886 
1887 	return !memcmp(prefix, option, plen);
1888 }
1889 
1890 static inline int selinux_option(char *option, int len)
1891 {
1892 	return (match_prefix("context=", sizeof("context=")-1, option, len) ||
1893 	        match_prefix("fscontext=", sizeof("fscontext=")-1, option, len) ||
1894 	        match_prefix("defcontext=", sizeof("defcontext=")-1, option, len));
1895 }
1896 
1897 static inline void take_option(char **to, char *from, int *first, int len)
1898 {
1899 	if (!*first) {
1900 		**to = ',';
1901 		*to += 1;
1902 	}
1903 	else
1904 		*first = 0;
1905 	memcpy(*to, from, len);
1906 	*to += len;
1907 }
1908 
1909 static int selinux_sb_copy_data(struct file_system_type *type, void *orig, void *copy)
1910 {
1911 	int fnosec, fsec, rc = 0;
1912 	char *in_save, *in_curr, *in_end;
1913 	char *sec_curr, *nosec_save, *nosec;
1914 
1915 	in_curr = orig;
1916 	sec_curr = copy;
1917 
1918 	/* Binary mount data: just copy */
1919 	if (type->fs_flags & FS_BINARY_MOUNTDATA) {
1920 		copy_page(sec_curr, in_curr);
1921 		goto out;
1922 	}
1923 
1924 	nosec = (char *)get_zeroed_page(GFP_KERNEL);
1925 	if (!nosec) {
1926 		rc = -ENOMEM;
1927 		goto out;
1928 	}
1929 
1930 	nosec_save = nosec;
1931 	fnosec = fsec = 1;
1932 	in_save = in_end = orig;
1933 
1934 	do {
1935 		if (*in_end == ',' || *in_end == '\0') {
1936 			int len = in_end - in_curr;
1937 
1938 			if (selinux_option(in_curr, len))
1939 				take_option(&sec_curr, in_curr, &fsec, len);
1940 			else
1941 				take_option(&nosec, in_curr, &fnosec, len);
1942 
1943 			in_curr = in_end + 1;
1944 		}
1945 	} while (*in_end++);
1946 
1947 	copy_page(in_save, nosec_save);
1948 out:
1949 	return rc;
1950 }
1951 
1952 static int selinux_sb_kern_mount(struct super_block *sb, void *data)
1953 {
1954 	struct avc_audit_data ad;
1955 	int rc;
1956 
1957 	rc = superblock_doinit(sb, data);
1958 	if (rc)
1959 		return rc;
1960 
1961 	AVC_AUDIT_DATA_INIT(&ad,FS);
1962 	ad.u.fs.dentry = sb->s_root;
1963 	return superblock_has_perm(current, sb, FILESYSTEM__MOUNT, &ad);
1964 }
1965 
1966 static int selinux_sb_statfs(struct super_block *sb)
1967 {
1968 	struct avc_audit_data ad;
1969 
1970 	AVC_AUDIT_DATA_INIT(&ad,FS);
1971 	ad.u.fs.dentry = sb->s_root;
1972 	return superblock_has_perm(current, sb, FILESYSTEM__GETATTR, &ad);
1973 }
1974 
1975 static int selinux_mount(char * dev_name,
1976                          struct nameidata *nd,
1977                          char * type,
1978                          unsigned long flags,
1979                          void * data)
1980 {
1981 	int rc;
1982 
1983 	rc = secondary_ops->sb_mount(dev_name, nd, type, flags, data);
1984 	if (rc)
1985 		return rc;
1986 
1987 	if (flags & MS_REMOUNT)
1988 		return superblock_has_perm(current, nd->mnt->mnt_sb,
1989 		                           FILESYSTEM__REMOUNT, NULL);
1990 	else
1991 		return dentry_has_perm(current, nd->mnt, nd->dentry,
1992 		                       FILE__MOUNTON);
1993 }
1994 
1995 static int selinux_umount(struct vfsmount *mnt, int flags)
1996 {
1997 	int rc;
1998 
1999 	rc = secondary_ops->sb_umount(mnt, flags);
2000 	if (rc)
2001 		return rc;
2002 
2003 	return superblock_has_perm(current,mnt->mnt_sb,
2004 	                           FILESYSTEM__UNMOUNT,NULL);
2005 }
2006 
2007 /* inode security operations */
2008 
2009 static int selinux_inode_alloc_security(struct inode *inode)
2010 {
2011 	return inode_alloc_security(inode);
2012 }
2013 
2014 static void selinux_inode_free_security(struct inode *inode)
2015 {
2016 	inode_free_security(inode);
2017 }
2018 
2019 static int selinux_inode_create(struct inode *dir, struct dentry *dentry, int mask)
2020 {
2021 	return may_create(dir, dentry, SECCLASS_FILE);
2022 }
2023 
2024 static void selinux_inode_post_create(struct inode *dir, struct dentry *dentry, int mask)
2025 {
2026 	post_create(dir, dentry);
2027 }
2028 
2029 static int selinux_inode_link(struct dentry *old_dentry, struct inode *dir, struct dentry *new_dentry)
2030 {
2031 	int rc;
2032 
2033 	rc = secondary_ops->inode_link(old_dentry,dir,new_dentry);
2034 	if (rc)
2035 		return rc;
2036 	return may_link(dir, old_dentry, MAY_LINK);
2037 }
2038 
2039 static void selinux_inode_post_link(struct dentry *old_dentry, struct inode *inode, struct dentry *new_dentry)
2040 {
2041 	return;
2042 }
2043 
2044 static int selinux_inode_unlink(struct inode *dir, struct dentry *dentry)
2045 {
2046 	int rc;
2047 
2048 	rc = secondary_ops->inode_unlink(dir, dentry);
2049 	if (rc)
2050 		return rc;
2051 	return may_link(dir, dentry, MAY_UNLINK);
2052 }
2053 
2054 static int selinux_inode_symlink(struct inode *dir, struct dentry *dentry, const char *name)
2055 {
2056 	return may_create(dir, dentry, SECCLASS_LNK_FILE);
2057 }
2058 
2059 static void selinux_inode_post_symlink(struct inode *dir, struct dentry *dentry, const char *name)
2060 {
2061 	post_create(dir, dentry);
2062 }
2063 
2064 static int selinux_inode_mkdir(struct inode *dir, struct dentry *dentry, int mask)
2065 {
2066 	return may_create(dir, dentry, SECCLASS_DIR);
2067 }
2068 
2069 static void selinux_inode_post_mkdir(struct inode *dir, struct dentry *dentry, int mask)
2070 {
2071 	post_create(dir, dentry);
2072 }
2073 
2074 static int selinux_inode_rmdir(struct inode *dir, struct dentry *dentry)
2075 {
2076 	return may_link(dir, dentry, MAY_RMDIR);
2077 }
2078 
2079 static int selinux_inode_mknod(struct inode *dir, struct dentry *dentry, int mode, dev_t dev)
2080 {
2081 	int rc;
2082 
2083 	rc = secondary_ops->inode_mknod(dir, dentry, mode, dev);
2084 	if (rc)
2085 		return rc;
2086 
2087 	return may_create(dir, dentry, inode_mode_to_security_class(mode));
2088 }
2089 
2090 static void selinux_inode_post_mknod(struct inode *dir, struct dentry *dentry, int mode, dev_t dev)
2091 {
2092 	post_create(dir, dentry);
2093 }
2094 
2095 static int selinux_inode_rename(struct inode *old_inode, struct dentry *old_dentry,
2096                                 struct inode *new_inode, struct dentry *new_dentry)
2097 {
2098 	return may_rename(old_inode, old_dentry, new_inode, new_dentry);
2099 }
2100 
2101 static void selinux_inode_post_rename(struct inode *old_inode, struct dentry *old_dentry,
2102                                       struct inode *new_inode, struct dentry *new_dentry)
2103 {
2104 	return;
2105 }
2106 
2107 static int selinux_inode_readlink(struct dentry *dentry)
2108 {
2109 	return dentry_has_perm(current, NULL, dentry, FILE__READ);
2110 }
2111 
2112 static int selinux_inode_follow_link(struct dentry *dentry, struct nameidata *nameidata)
2113 {
2114 	int rc;
2115 
2116 	rc = secondary_ops->inode_follow_link(dentry,nameidata);
2117 	if (rc)
2118 		return rc;
2119 	return dentry_has_perm(current, NULL, dentry, FILE__READ);
2120 }
2121 
2122 static int selinux_inode_permission(struct inode *inode, int mask,
2123 				    struct nameidata *nd)
2124 {
2125 	int rc;
2126 
2127 	rc = secondary_ops->inode_permission(inode, mask, nd);
2128 	if (rc)
2129 		return rc;
2130 
2131 	if (!mask) {
2132 		/* No permission to check.  Existence test. */
2133 		return 0;
2134 	}
2135 
2136 	return inode_has_perm(current, inode,
2137 			       file_mask_to_av(inode->i_mode, mask), NULL);
2138 }
2139 
2140 static int selinux_inode_setattr(struct dentry *dentry, struct iattr *iattr)
2141 {
2142 	int rc;
2143 
2144 	rc = secondary_ops->inode_setattr(dentry, iattr);
2145 	if (rc)
2146 		return rc;
2147 
2148 	if (iattr->ia_valid & ATTR_FORCE)
2149 		return 0;
2150 
2151 	if (iattr->ia_valid & (ATTR_MODE | ATTR_UID | ATTR_GID |
2152 			       ATTR_ATIME_SET | ATTR_MTIME_SET))
2153 		return dentry_has_perm(current, NULL, dentry, FILE__SETATTR);
2154 
2155 	return dentry_has_perm(current, NULL, dentry, FILE__WRITE);
2156 }
2157 
2158 static int selinux_inode_getattr(struct vfsmount *mnt, struct dentry *dentry)
2159 {
2160 	return dentry_has_perm(current, mnt, dentry, FILE__GETATTR);
2161 }
2162 
2163 static int selinux_inode_setxattr(struct dentry *dentry, char *name, void *value, size_t size, int flags)
2164 {
2165 	struct task_security_struct *tsec = current->security;
2166 	struct inode *inode = dentry->d_inode;
2167 	struct inode_security_struct *isec = inode->i_security;
2168 	struct superblock_security_struct *sbsec;
2169 	struct avc_audit_data ad;
2170 	u32 newsid;
2171 	int rc = 0;
2172 
2173 	if (strcmp(name, XATTR_NAME_SELINUX)) {
2174 		if (!strncmp(name, XATTR_SECURITY_PREFIX,
2175 			     sizeof XATTR_SECURITY_PREFIX - 1) &&
2176 		    !capable(CAP_SYS_ADMIN)) {
2177 			/* A different attribute in the security namespace.
2178 			   Restrict to administrator. */
2179 			return -EPERM;
2180 		}
2181 
2182 		/* Not an attribute we recognize, so just check the
2183 		   ordinary setattr permission. */
2184 		return dentry_has_perm(current, NULL, dentry, FILE__SETATTR);
2185 	}
2186 
2187 	sbsec = inode->i_sb->s_security;
2188 	if (sbsec->behavior == SECURITY_FS_USE_MNTPOINT)
2189 		return -EOPNOTSUPP;
2190 
2191 	if ((current->fsuid != inode->i_uid) && !capable(CAP_FOWNER))
2192 		return -EPERM;
2193 
2194 	AVC_AUDIT_DATA_INIT(&ad,FS);
2195 	ad.u.fs.dentry = dentry;
2196 
2197 	rc = avc_has_perm(tsec->sid, isec->sid, isec->sclass,
2198 			  FILE__RELABELFROM, &ad);
2199 	if (rc)
2200 		return rc;
2201 
2202 	rc = security_context_to_sid(value, size, &newsid);
2203 	if (rc)
2204 		return rc;
2205 
2206 	rc = avc_has_perm(tsec->sid, newsid, isec->sclass,
2207 			  FILE__RELABELTO, &ad);
2208 	if (rc)
2209 		return rc;
2210 
2211 	rc = security_validate_transition(isec->sid, newsid, tsec->sid,
2212 	                                  isec->sclass);
2213 	if (rc)
2214 		return rc;
2215 
2216 	return avc_has_perm(newsid,
2217 			    sbsec->sid,
2218 			    SECCLASS_FILESYSTEM,
2219 			    FILESYSTEM__ASSOCIATE,
2220 			    &ad);
2221 }
2222 
2223 static void selinux_inode_post_setxattr(struct dentry *dentry, char *name,
2224                                         void *value, size_t size, int flags)
2225 {
2226 	struct inode *inode = dentry->d_inode;
2227 	struct inode_security_struct *isec = inode->i_security;
2228 	u32 newsid;
2229 	int rc;
2230 
2231 	if (strcmp(name, XATTR_NAME_SELINUX)) {
2232 		/* Not an attribute we recognize, so nothing to do. */
2233 		return;
2234 	}
2235 
2236 	rc = security_context_to_sid(value, size, &newsid);
2237 	if (rc) {
2238 		printk(KERN_WARNING "%s:  unable to obtain SID for context "
2239 		       "%s, rc=%d\n", __FUNCTION__, (char*)value, -rc);
2240 		return;
2241 	}
2242 
2243 	isec->sid = newsid;
2244 	return;
2245 }
2246 
2247 static int selinux_inode_getxattr (struct dentry *dentry, char *name)
2248 {
2249 	struct inode *inode = dentry->d_inode;
2250 	struct superblock_security_struct *sbsec = inode->i_sb->s_security;
2251 
2252 	if (sbsec->behavior == SECURITY_FS_USE_MNTPOINT)
2253 		return -EOPNOTSUPP;
2254 
2255 	return dentry_has_perm(current, NULL, dentry, FILE__GETATTR);
2256 }
2257 
2258 static int selinux_inode_listxattr (struct dentry *dentry)
2259 {
2260 	return dentry_has_perm(current, NULL, dentry, FILE__GETATTR);
2261 }
2262 
2263 static int selinux_inode_removexattr (struct dentry *dentry, char *name)
2264 {
2265 	if (strcmp(name, XATTR_NAME_SELINUX)) {
2266 		if (!strncmp(name, XATTR_SECURITY_PREFIX,
2267 			     sizeof XATTR_SECURITY_PREFIX - 1) &&
2268 		    !capable(CAP_SYS_ADMIN)) {
2269 			/* A different attribute in the security namespace.
2270 			   Restrict to administrator. */
2271 			return -EPERM;
2272 		}
2273 
2274 		/* Not an attribute we recognize, so just check the
2275 		   ordinary setattr permission. Might want a separate
2276 		   permission for removexattr. */
2277 		return dentry_has_perm(current, NULL, dentry, FILE__SETATTR);
2278 	}
2279 
2280 	/* No one is allowed to remove a SELinux security label.
2281 	   You can change the label, but all data must be labeled. */
2282 	return -EACCES;
2283 }
2284 
2285 static int selinux_inode_getsecurity(struct inode *inode, const char *name, void *buffer, size_t size)
2286 {
2287 	struct inode_security_struct *isec = inode->i_security;
2288 	char *context;
2289 	unsigned len;
2290 	int rc;
2291 
2292 	/* Permission check handled by selinux_inode_getxattr hook.*/
2293 
2294 	if (strcmp(name, XATTR_SELINUX_SUFFIX))
2295 		return -EOPNOTSUPP;
2296 
2297 	rc = security_sid_to_context(isec->sid, &context, &len);
2298 	if (rc)
2299 		return rc;
2300 
2301 	if (!buffer || !size) {
2302 		kfree(context);
2303 		return len;
2304 	}
2305 	if (size < len) {
2306 		kfree(context);
2307 		return -ERANGE;
2308 	}
2309 	memcpy(buffer, context, len);
2310 	kfree(context);
2311 	return len;
2312 }
2313 
2314 static int selinux_inode_setsecurity(struct inode *inode, const char *name,
2315                                      const void *value, size_t size, int flags)
2316 {
2317 	struct inode_security_struct *isec = inode->i_security;
2318 	u32 newsid;
2319 	int rc;
2320 
2321 	if (strcmp(name, XATTR_SELINUX_SUFFIX))
2322 		return -EOPNOTSUPP;
2323 
2324 	if (!value || !size)
2325 		return -EACCES;
2326 
2327 	rc = security_context_to_sid((void*)value, size, &newsid);
2328 	if (rc)
2329 		return rc;
2330 
2331 	isec->sid = newsid;
2332 	return 0;
2333 }
2334 
2335 static int selinux_inode_listsecurity(struct inode *inode, char *buffer, size_t buffer_size)
2336 {
2337 	const int len = sizeof(XATTR_NAME_SELINUX);
2338 	if (buffer && len <= buffer_size)
2339 		memcpy(buffer, XATTR_NAME_SELINUX, len);
2340 	return len;
2341 }
2342 
2343 /* file security operations */
2344 
2345 static int selinux_file_permission(struct file *file, int mask)
2346 {
2347 	struct inode *inode = file->f_dentry->d_inode;
2348 
2349 	if (!mask) {
2350 		/* No permission to check.  Existence test. */
2351 		return 0;
2352 	}
2353 
2354 	/* file_mask_to_av won't add FILE__WRITE if MAY_APPEND is set */
2355 	if ((file->f_flags & O_APPEND) && (mask & MAY_WRITE))
2356 		mask |= MAY_APPEND;
2357 
2358 	return file_has_perm(current, file,
2359 			     file_mask_to_av(inode->i_mode, mask));
2360 }
2361 
2362 static int selinux_file_alloc_security(struct file *file)
2363 {
2364 	return file_alloc_security(file);
2365 }
2366 
2367 static void selinux_file_free_security(struct file *file)
2368 {
2369 	file_free_security(file);
2370 }
2371 
2372 static int selinux_file_ioctl(struct file *file, unsigned int cmd,
2373 			      unsigned long arg)
2374 {
2375 	int error = 0;
2376 
2377 	switch (cmd) {
2378 		case FIONREAD:
2379 		/* fall through */
2380 		case FIBMAP:
2381 		/* fall through */
2382 		case FIGETBSZ:
2383 		/* fall through */
2384 		case EXT2_IOC_GETFLAGS:
2385 		/* fall through */
2386 		case EXT2_IOC_GETVERSION:
2387 			error = file_has_perm(current, file, FILE__GETATTR);
2388 			break;
2389 
2390 		case EXT2_IOC_SETFLAGS:
2391 		/* fall through */
2392 		case EXT2_IOC_SETVERSION:
2393 			error = file_has_perm(current, file, FILE__SETATTR);
2394 			break;
2395 
2396 		/* sys_ioctl() checks */
2397 		case FIONBIO:
2398 		/* fall through */
2399 		case FIOASYNC:
2400 			error = file_has_perm(current, file, 0);
2401 			break;
2402 
2403 	        case KDSKBENT:
2404 	        case KDSKBSENT:
2405 			error = task_has_capability(current,CAP_SYS_TTY_CONFIG);
2406 			break;
2407 
2408 		/* default case assumes that the command will go
2409 		 * to the file's ioctl() function.
2410 		 */
2411 		default:
2412 			error = file_has_perm(current, file, FILE__IOCTL);
2413 
2414 	}
2415 	return error;
2416 }
2417 
2418 static int file_map_prot_check(struct file *file, unsigned long prot, int shared)
2419 {
2420 #ifndef CONFIG_PPC32
2421 	if ((prot & PROT_EXEC) && (!file || (!shared && (prot & PROT_WRITE)))) {
2422 		/*
2423 		 * We are making executable an anonymous mapping or a
2424 		 * private file mapping that will also be writable.
2425 		 * This has an additional check.
2426 		 */
2427 		int rc = task_has_perm(current, current, PROCESS__EXECMEM);
2428 		if (rc)
2429 			return rc;
2430 	}
2431 #endif
2432 
2433 	if (file) {
2434 		/* read access is always possible with a mapping */
2435 		u32 av = FILE__READ;
2436 
2437 		/* write access only matters if the mapping is shared */
2438 		if (shared && (prot & PROT_WRITE))
2439 			av |= FILE__WRITE;
2440 
2441 		if (prot & PROT_EXEC)
2442 			av |= FILE__EXECUTE;
2443 
2444 		return file_has_perm(current, file, av);
2445 	}
2446 	return 0;
2447 }
2448 
2449 static int selinux_file_mmap(struct file *file, unsigned long reqprot,
2450 			     unsigned long prot, unsigned long flags)
2451 {
2452 	int rc;
2453 
2454 	rc = secondary_ops->file_mmap(file, reqprot, prot, flags);
2455 	if (rc)
2456 		return rc;
2457 
2458 	if (selinux_checkreqprot)
2459 		prot = reqprot;
2460 
2461 	return file_map_prot_check(file, prot,
2462 				   (flags & MAP_TYPE) == MAP_SHARED);
2463 }
2464 
2465 static int selinux_file_mprotect(struct vm_area_struct *vma,
2466 				 unsigned long reqprot,
2467 				 unsigned long prot)
2468 {
2469 	int rc;
2470 
2471 	rc = secondary_ops->file_mprotect(vma, reqprot, prot);
2472 	if (rc)
2473 		return rc;
2474 
2475 	if (selinux_checkreqprot)
2476 		prot = reqprot;
2477 
2478 #ifndef CONFIG_PPC32
2479 	if (vma->vm_file != NULL && vma->anon_vma != NULL && (prot & PROT_EXEC)) {
2480 		/*
2481 		 * We are making executable a file mapping that has
2482 		 * had some COW done. Since pages might have been written,
2483 		 * check ability to execute the possibly modified content.
2484 		 * This typically should only occur for text relocations.
2485 		 */
2486 		int rc = file_has_perm(current, vma->vm_file, FILE__EXECMOD);
2487 		if (rc)
2488 			return rc;
2489 	}
2490 #endif
2491 
2492 	return file_map_prot_check(vma->vm_file, prot, vma->vm_flags&VM_SHARED);
2493 }
2494 
2495 static int selinux_file_lock(struct file *file, unsigned int cmd)
2496 {
2497 	return file_has_perm(current, file, FILE__LOCK);
2498 }
2499 
2500 static int selinux_file_fcntl(struct file *file, unsigned int cmd,
2501 			      unsigned long arg)
2502 {
2503 	int err = 0;
2504 
2505 	switch (cmd) {
2506 	        case F_SETFL:
2507 			if (!file->f_dentry || !file->f_dentry->d_inode) {
2508 				err = -EINVAL;
2509 				break;
2510 			}
2511 
2512 			if ((file->f_flags & O_APPEND) && !(arg & O_APPEND)) {
2513 				err = file_has_perm(current, file,FILE__WRITE);
2514 				break;
2515 			}
2516 			/* fall through */
2517 	        case F_SETOWN:
2518 	        case F_SETSIG:
2519 	        case F_GETFL:
2520 	        case F_GETOWN:
2521 	        case F_GETSIG:
2522 			/* Just check FD__USE permission */
2523 			err = file_has_perm(current, file, 0);
2524 			break;
2525 		case F_GETLK:
2526 		case F_SETLK:
2527 	        case F_SETLKW:
2528 #if BITS_PER_LONG == 32
2529 	        case F_GETLK64:
2530 		case F_SETLK64:
2531 	        case F_SETLKW64:
2532 #endif
2533 			if (!file->f_dentry || !file->f_dentry->d_inode) {
2534 				err = -EINVAL;
2535 				break;
2536 			}
2537 			err = file_has_perm(current, file, FILE__LOCK);
2538 			break;
2539 	}
2540 
2541 	return err;
2542 }
2543 
2544 static int selinux_file_set_fowner(struct file *file)
2545 {
2546 	struct task_security_struct *tsec;
2547 	struct file_security_struct *fsec;
2548 
2549 	tsec = current->security;
2550 	fsec = file->f_security;
2551 	fsec->fown_sid = tsec->sid;
2552 
2553 	return 0;
2554 }
2555 
2556 static int selinux_file_send_sigiotask(struct task_struct *tsk,
2557 				       struct fown_struct *fown, int signum)
2558 {
2559         struct file *file;
2560 	u32 perm;
2561 	struct task_security_struct *tsec;
2562 	struct file_security_struct *fsec;
2563 
2564 	/* struct fown_struct is never outside the context of a struct file */
2565         file = (struct file *)((long)fown - offsetof(struct file,f_owner));
2566 
2567 	tsec = tsk->security;
2568 	fsec = file->f_security;
2569 
2570 	if (!signum)
2571 		perm = signal_to_av(SIGIO); /* as per send_sigio_to_task */
2572 	else
2573 		perm = signal_to_av(signum);
2574 
2575 	return avc_has_perm(fsec->fown_sid, tsec->sid,
2576 			    SECCLASS_PROCESS, perm, NULL);
2577 }
2578 
2579 static int selinux_file_receive(struct file *file)
2580 {
2581 	return file_has_perm(current, file, file_to_av(file));
2582 }
2583 
2584 /* task security operations */
2585 
2586 static int selinux_task_create(unsigned long clone_flags)
2587 {
2588 	int rc;
2589 
2590 	rc = secondary_ops->task_create(clone_flags);
2591 	if (rc)
2592 		return rc;
2593 
2594 	return task_has_perm(current, current, PROCESS__FORK);
2595 }
2596 
2597 static int selinux_task_alloc_security(struct task_struct *tsk)
2598 {
2599 	struct task_security_struct *tsec1, *tsec2;
2600 	int rc;
2601 
2602 	tsec1 = current->security;
2603 
2604 	rc = task_alloc_security(tsk);
2605 	if (rc)
2606 		return rc;
2607 	tsec2 = tsk->security;
2608 
2609 	tsec2->osid = tsec1->osid;
2610 	tsec2->sid = tsec1->sid;
2611 
2612 	/* Retain the exec and create SIDs across fork */
2613 	tsec2->exec_sid = tsec1->exec_sid;
2614 	tsec2->create_sid = tsec1->create_sid;
2615 
2616 	/* Retain ptracer SID across fork, if any.
2617 	   This will be reset by the ptrace hook upon any
2618 	   subsequent ptrace_attach operations. */
2619 	tsec2->ptrace_sid = tsec1->ptrace_sid;
2620 
2621 	return 0;
2622 }
2623 
2624 static void selinux_task_free_security(struct task_struct *tsk)
2625 {
2626 	task_free_security(tsk);
2627 }
2628 
2629 static int selinux_task_setuid(uid_t id0, uid_t id1, uid_t id2, int flags)
2630 {
2631 	/* Since setuid only affects the current process, and
2632 	   since the SELinux controls are not based on the Linux
2633 	   identity attributes, SELinux does not need to control
2634 	   this operation.  However, SELinux does control the use
2635 	   of the CAP_SETUID and CAP_SETGID capabilities using the
2636 	   capable hook. */
2637 	return 0;
2638 }
2639 
2640 static int selinux_task_post_setuid(uid_t id0, uid_t id1, uid_t id2, int flags)
2641 {
2642 	return secondary_ops->task_post_setuid(id0,id1,id2,flags);
2643 }
2644 
2645 static int selinux_task_setgid(gid_t id0, gid_t id1, gid_t id2, int flags)
2646 {
2647 	/* See the comment for setuid above. */
2648 	return 0;
2649 }
2650 
2651 static int selinux_task_setpgid(struct task_struct *p, pid_t pgid)
2652 {
2653 	return task_has_perm(current, p, PROCESS__SETPGID);
2654 }
2655 
2656 static int selinux_task_getpgid(struct task_struct *p)
2657 {
2658 	return task_has_perm(current, p, PROCESS__GETPGID);
2659 }
2660 
2661 static int selinux_task_getsid(struct task_struct *p)
2662 {
2663 	return task_has_perm(current, p, PROCESS__GETSESSION);
2664 }
2665 
2666 static int selinux_task_setgroups(struct group_info *group_info)
2667 {
2668 	/* See the comment for setuid above. */
2669 	return 0;
2670 }
2671 
2672 static int selinux_task_setnice(struct task_struct *p, int nice)
2673 {
2674 	int rc;
2675 
2676 	rc = secondary_ops->task_setnice(p, nice);
2677 	if (rc)
2678 		return rc;
2679 
2680 	return task_has_perm(current,p, PROCESS__SETSCHED);
2681 }
2682 
2683 static int selinux_task_setrlimit(unsigned int resource, struct rlimit *new_rlim)
2684 {
2685 	struct rlimit *old_rlim = current->signal->rlim + resource;
2686 	int rc;
2687 
2688 	rc = secondary_ops->task_setrlimit(resource, new_rlim);
2689 	if (rc)
2690 		return rc;
2691 
2692 	/* Control the ability to change the hard limit (whether
2693 	   lowering or raising it), so that the hard limit can
2694 	   later be used as a safe reset point for the soft limit
2695 	   upon context transitions. See selinux_bprm_apply_creds. */
2696 	if (old_rlim->rlim_max != new_rlim->rlim_max)
2697 		return task_has_perm(current, current, PROCESS__SETRLIMIT);
2698 
2699 	return 0;
2700 }
2701 
2702 static int selinux_task_setscheduler(struct task_struct *p, int policy, struct sched_param *lp)
2703 {
2704 	return task_has_perm(current, p, PROCESS__SETSCHED);
2705 }
2706 
2707 static int selinux_task_getscheduler(struct task_struct *p)
2708 {
2709 	return task_has_perm(current, p, PROCESS__GETSCHED);
2710 }
2711 
2712 static int selinux_task_kill(struct task_struct *p, struct siginfo *info, int sig)
2713 {
2714 	u32 perm;
2715 	int rc;
2716 
2717 	rc = secondary_ops->task_kill(p, info, sig);
2718 	if (rc)
2719 		return rc;
2720 
2721 	if (info && ((unsigned long)info == 1 ||
2722 	             (unsigned long)info == 2 || SI_FROMKERNEL(info)))
2723 		return 0;
2724 
2725 	if (!sig)
2726 		perm = PROCESS__SIGNULL; /* null signal; existence test */
2727 	else
2728 		perm = signal_to_av(sig);
2729 
2730 	return task_has_perm(current, p, perm);
2731 }
2732 
2733 static int selinux_task_prctl(int option,
2734 			      unsigned long arg2,
2735 			      unsigned long arg3,
2736 			      unsigned long arg4,
2737 			      unsigned long arg5)
2738 {
2739 	/* The current prctl operations do not appear to require
2740 	   any SELinux controls since they merely observe or modify
2741 	   the state of the current process. */
2742 	return 0;
2743 }
2744 
2745 static int selinux_task_wait(struct task_struct *p)
2746 {
2747 	u32 perm;
2748 
2749 	perm = signal_to_av(p->exit_signal);
2750 
2751 	return task_has_perm(p, current, perm);
2752 }
2753 
2754 static void selinux_task_reparent_to_init(struct task_struct *p)
2755 {
2756   	struct task_security_struct *tsec;
2757 
2758 	secondary_ops->task_reparent_to_init(p);
2759 
2760 	tsec = p->security;
2761 	tsec->osid = tsec->sid;
2762 	tsec->sid = SECINITSID_KERNEL;
2763 	return;
2764 }
2765 
2766 static void selinux_task_to_inode(struct task_struct *p,
2767 				  struct inode *inode)
2768 {
2769 	struct task_security_struct *tsec = p->security;
2770 	struct inode_security_struct *isec = inode->i_security;
2771 
2772 	isec->sid = tsec->sid;
2773 	isec->initialized = 1;
2774 	return;
2775 }
2776 
2777 #ifdef CONFIG_SECURITY_NETWORK
2778 
2779 /* Returns error only if unable to parse addresses */
2780 static int selinux_parse_skb_ipv4(struct sk_buff *skb, struct avc_audit_data *ad)
2781 {
2782 	int offset, ihlen, ret = -EINVAL;
2783 	struct iphdr _iph, *ih;
2784 
2785 	offset = skb->nh.raw - skb->data;
2786 	ih = skb_header_pointer(skb, offset, sizeof(_iph), &_iph);
2787 	if (ih == NULL)
2788 		goto out;
2789 
2790 	ihlen = ih->ihl * 4;
2791 	if (ihlen < sizeof(_iph))
2792 		goto out;
2793 
2794 	ad->u.net.v4info.saddr = ih->saddr;
2795 	ad->u.net.v4info.daddr = ih->daddr;
2796 	ret = 0;
2797 
2798 	switch (ih->protocol) {
2799         case IPPROTO_TCP: {
2800         	struct tcphdr _tcph, *th;
2801 
2802         	if (ntohs(ih->frag_off) & IP_OFFSET)
2803         		break;
2804 
2805 		offset += ihlen;
2806 		th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph);
2807 		if (th == NULL)
2808 			break;
2809 
2810 		ad->u.net.sport = th->source;
2811 		ad->u.net.dport = th->dest;
2812 		break;
2813         }
2814 
2815         case IPPROTO_UDP: {
2816         	struct udphdr _udph, *uh;
2817 
2818         	if (ntohs(ih->frag_off) & IP_OFFSET)
2819         		break;
2820 
2821 		offset += ihlen;
2822         	uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph);
2823 		if (uh == NULL)
2824 			break;
2825 
2826         	ad->u.net.sport = uh->source;
2827         	ad->u.net.dport = uh->dest;
2828         	break;
2829         }
2830 
2831         default:
2832         	break;
2833         }
2834 out:
2835 	return ret;
2836 }
2837 
2838 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
2839 
2840 /* Returns error only if unable to parse addresses */
2841 static int selinux_parse_skb_ipv6(struct sk_buff *skb, struct avc_audit_data *ad)
2842 {
2843 	u8 nexthdr;
2844 	int ret = -EINVAL, offset;
2845 	struct ipv6hdr _ipv6h, *ip6;
2846 
2847 	offset = skb->nh.raw - skb->data;
2848 	ip6 = skb_header_pointer(skb, offset, sizeof(_ipv6h), &_ipv6h);
2849 	if (ip6 == NULL)
2850 		goto out;
2851 
2852 	ipv6_addr_copy(&ad->u.net.v6info.saddr, &ip6->saddr);
2853 	ipv6_addr_copy(&ad->u.net.v6info.daddr, &ip6->daddr);
2854 	ret = 0;
2855 
2856 	nexthdr = ip6->nexthdr;
2857 	offset += sizeof(_ipv6h);
2858 	offset = ipv6_skip_exthdr(skb, offset, &nexthdr);
2859 	if (offset < 0)
2860 		goto out;
2861 
2862 	switch (nexthdr) {
2863 	case IPPROTO_TCP: {
2864         	struct tcphdr _tcph, *th;
2865 
2866 		th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph);
2867 		if (th == NULL)
2868 			break;
2869 
2870 		ad->u.net.sport = th->source;
2871 		ad->u.net.dport = th->dest;
2872 		break;
2873 	}
2874 
2875 	case IPPROTO_UDP: {
2876 		struct udphdr _udph, *uh;
2877 
2878 		uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph);
2879 		if (uh == NULL)
2880 			break;
2881 
2882 		ad->u.net.sport = uh->source;
2883 		ad->u.net.dport = uh->dest;
2884 		break;
2885 	}
2886 
2887 	/* includes fragments */
2888 	default:
2889 		break;
2890 	}
2891 out:
2892 	return ret;
2893 }
2894 
2895 #endif /* IPV6 */
2896 
2897 static int selinux_parse_skb(struct sk_buff *skb, struct avc_audit_data *ad,
2898 			     char **addrp, int *len, int src)
2899 {
2900 	int ret = 0;
2901 
2902 	switch (ad->u.net.family) {
2903 	case PF_INET:
2904 		ret = selinux_parse_skb_ipv4(skb, ad);
2905 		if (ret || !addrp)
2906 			break;
2907 		*len = 4;
2908 		*addrp = (char *)(src ? &ad->u.net.v4info.saddr :
2909 					&ad->u.net.v4info.daddr);
2910 		break;
2911 
2912 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
2913 	case PF_INET6:
2914 		ret = selinux_parse_skb_ipv6(skb, ad);
2915 		if (ret || !addrp)
2916 			break;
2917 		*len = 16;
2918 		*addrp = (char *)(src ? &ad->u.net.v6info.saddr :
2919 					&ad->u.net.v6info.daddr);
2920 		break;
2921 #endif	/* IPV6 */
2922 	default:
2923 		break;
2924 	}
2925 
2926 	return ret;
2927 }
2928 
2929 /* socket security operations */
2930 static int socket_has_perm(struct task_struct *task, struct socket *sock,
2931 			   u32 perms)
2932 {
2933 	struct inode_security_struct *isec;
2934 	struct task_security_struct *tsec;
2935 	struct avc_audit_data ad;
2936 	int err = 0;
2937 
2938 	tsec = task->security;
2939 	isec = SOCK_INODE(sock)->i_security;
2940 
2941 	if (isec->sid == SECINITSID_KERNEL)
2942 		goto out;
2943 
2944 	AVC_AUDIT_DATA_INIT(&ad,NET);
2945 	ad.u.net.sk = sock->sk;
2946 	err = avc_has_perm(tsec->sid, isec->sid, isec->sclass, perms, &ad);
2947 
2948 out:
2949 	return err;
2950 }
2951 
2952 static int selinux_socket_create(int family, int type,
2953 				 int protocol, int kern)
2954 {
2955 	int err = 0;
2956 	struct task_security_struct *tsec;
2957 
2958 	if (kern)
2959 		goto out;
2960 
2961 	tsec = current->security;
2962 	err = avc_has_perm(tsec->sid, tsec->sid,
2963 			   socket_type_to_security_class(family, type,
2964 			   protocol), SOCKET__CREATE, NULL);
2965 
2966 out:
2967 	return err;
2968 }
2969 
2970 static void selinux_socket_post_create(struct socket *sock, int family,
2971 				       int type, int protocol, int kern)
2972 {
2973 	struct inode_security_struct *isec;
2974 	struct task_security_struct *tsec;
2975 
2976 	isec = SOCK_INODE(sock)->i_security;
2977 
2978 	tsec = current->security;
2979 	isec->sclass = socket_type_to_security_class(family, type, protocol);
2980 	isec->sid = kern ? SECINITSID_KERNEL : tsec->sid;
2981 	isec->initialized = 1;
2982 
2983 	return;
2984 }
2985 
2986 /* Range of port numbers used to automatically bind.
2987    Need to determine whether we should perform a name_bind
2988    permission check between the socket and the port number. */
2989 #define ip_local_port_range_0 sysctl_local_port_range[0]
2990 #define ip_local_port_range_1 sysctl_local_port_range[1]
2991 
2992 static int selinux_socket_bind(struct socket *sock, struct sockaddr *address, int addrlen)
2993 {
2994 	u16 family;
2995 	int err;
2996 
2997 	err = socket_has_perm(current, sock, SOCKET__BIND);
2998 	if (err)
2999 		goto out;
3000 
3001 	/*
3002 	 * If PF_INET or PF_INET6, check name_bind permission for the port.
3003 	 */
3004 	family = sock->sk->sk_family;
3005 	if (family == PF_INET || family == PF_INET6) {
3006 		char *addrp;
3007 		struct inode_security_struct *isec;
3008 		struct task_security_struct *tsec;
3009 		struct avc_audit_data ad;
3010 		struct sockaddr_in *addr4 = NULL;
3011 		struct sockaddr_in6 *addr6 = NULL;
3012 		unsigned short snum;
3013 		struct sock *sk = sock->sk;
3014 		u32 sid, node_perm, addrlen;
3015 
3016 		tsec = current->security;
3017 		isec = SOCK_INODE(sock)->i_security;
3018 
3019 		if (family == PF_INET) {
3020 			addr4 = (struct sockaddr_in *)address;
3021 			snum = ntohs(addr4->sin_port);
3022 			addrlen = sizeof(addr4->sin_addr.s_addr);
3023 			addrp = (char *)&addr4->sin_addr.s_addr;
3024 		} else {
3025 			addr6 = (struct sockaddr_in6 *)address;
3026 			snum = ntohs(addr6->sin6_port);
3027 			addrlen = sizeof(addr6->sin6_addr.s6_addr);
3028 			addrp = (char *)&addr6->sin6_addr.s6_addr;
3029 		}
3030 
3031 		if (snum&&(snum < max(PROT_SOCK,ip_local_port_range_0) ||
3032 			   snum > ip_local_port_range_1)) {
3033 			err = security_port_sid(sk->sk_family, sk->sk_type,
3034 						sk->sk_protocol, snum, &sid);
3035 			if (err)
3036 				goto out;
3037 			AVC_AUDIT_DATA_INIT(&ad,NET);
3038 			ad.u.net.sport = htons(snum);
3039 			ad.u.net.family = family;
3040 			err = avc_has_perm(isec->sid, sid,
3041 					   isec->sclass,
3042 					   SOCKET__NAME_BIND, &ad);
3043 			if (err)
3044 				goto out;
3045 		}
3046 
3047 		switch(sk->sk_protocol) {
3048 		case IPPROTO_TCP:
3049 			node_perm = TCP_SOCKET__NODE_BIND;
3050 			break;
3051 
3052 		case IPPROTO_UDP:
3053 			node_perm = UDP_SOCKET__NODE_BIND;
3054 			break;
3055 
3056 		default:
3057 			node_perm = RAWIP_SOCKET__NODE_BIND;
3058 			break;
3059 		}
3060 
3061 		err = security_node_sid(family, addrp, addrlen, &sid);
3062 		if (err)
3063 			goto out;
3064 
3065 		AVC_AUDIT_DATA_INIT(&ad,NET);
3066 		ad.u.net.sport = htons(snum);
3067 		ad.u.net.family = family;
3068 
3069 		if (family == PF_INET)
3070 			ad.u.net.v4info.saddr = addr4->sin_addr.s_addr;
3071 		else
3072 			ipv6_addr_copy(&ad.u.net.v6info.saddr, &addr6->sin6_addr);
3073 
3074 		err = avc_has_perm(isec->sid, sid,
3075 		                   isec->sclass, node_perm, &ad);
3076 		if (err)
3077 			goto out;
3078 	}
3079 out:
3080 	return err;
3081 }
3082 
3083 static int selinux_socket_connect(struct socket *sock, struct sockaddr *address, int addrlen)
3084 {
3085 	struct inode_security_struct *isec;
3086 	int err;
3087 
3088 	err = socket_has_perm(current, sock, SOCKET__CONNECT);
3089 	if (err)
3090 		return err;
3091 
3092 	/*
3093 	 * If a TCP socket, check name_connect permission for the port.
3094 	 */
3095 	isec = SOCK_INODE(sock)->i_security;
3096 	if (isec->sclass == SECCLASS_TCP_SOCKET) {
3097 		struct sock *sk = sock->sk;
3098 		struct avc_audit_data ad;
3099 		struct sockaddr_in *addr4 = NULL;
3100 		struct sockaddr_in6 *addr6 = NULL;
3101 		unsigned short snum;
3102 		u32 sid;
3103 
3104 		if (sk->sk_family == PF_INET) {
3105 			addr4 = (struct sockaddr_in *)address;
3106 			if (addrlen != sizeof(struct sockaddr_in))
3107 				return -EINVAL;
3108 			snum = ntohs(addr4->sin_port);
3109 		} else {
3110 			addr6 = (struct sockaddr_in6 *)address;
3111 			if (addrlen != sizeof(struct sockaddr_in6))
3112 				return -EINVAL;
3113 			snum = ntohs(addr6->sin6_port);
3114 		}
3115 
3116 		err = security_port_sid(sk->sk_family, sk->sk_type,
3117 					sk->sk_protocol, snum, &sid);
3118 		if (err)
3119 			goto out;
3120 
3121 		AVC_AUDIT_DATA_INIT(&ad,NET);
3122 		ad.u.net.dport = htons(snum);
3123 		ad.u.net.family = sk->sk_family;
3124 		err = avc_has_perm(isec->sid, sid, isec->sclass,
3125 				   TCP_SOCKET__NAME_CONNECT, &ad);
3126 		if (err)
3127 			goto out;
3128 	}
3129 
3130 out:
3131 	return err;
3132 }
3133 
3134 static int selinux_socket_listen(struct socket *sock, int backlog)
3135 {
3136 	return socket_has_perm(current, sock, SOCKET__LISTEN);
3137 }
3138 
3139 static int selinux_socket_accept(struct socket *sock, struct socket *newsock)
3140 {
3141 	int err;
3142 	struct inode_security_struct *isec;
3143 	struct inode_security_struct *newisec;
3144 
3145 	err = socket_has_perm(current, sock, SOCKET__ACCEPT);
3146 	if (err)
3147 		return err;
3148 
3149 	newisec = SOCK_INODE(newsock)->i_security;
3150 
3151 	isec = SOCK_INODE(sock)->i_security;
3152 	newisec->sclass = isec->sclass;
3153 	newisec->sid = isec->sid;
3154 	newisec->initialized = 1;
3155 
3156 	return 0;
3157 }
3158 
3159 static int selinux_socket_sendmsg(struct socket *sock, struct msghdr *msg,
3160  				  int size)
3161 {
3162 	return socket_has_perm(current, sock, SOCKET__WRITE);
3163 }
3164 
3165 static int selinux_socket_recvmsg(struct socket *sock, struct msghdr *msg,
3166 				  int size, int flags)
3167 {
3168 	return socket_has_perm(current, sock, SOCKET__READ);
3169 }
3170 
3171 static int selinux_socket_getsockname(struct socket *sock)
3172 {
3173 	return socket_has_perm(current, sock, SOCKET__GETATTR);
3174 }
3175 
3176 static int selinux_socket_getpeername(struct socket *sock)
3177 {
3178 	return socket_has_perm(current, sock, SOCKET__GETATTR);
3179 }
3180 
3181 static int selinux_socket_setsockopt(struct socket *sock,int level,int optname)
3182 {
3183 	return socket_has_perm(current, sock, SOCKET__SETOPT);
3184 }
3185 
3186 static int selinux_socket_getsockopt(struct socket *sock, int level,
3187 				     int optname)
3188 {
3189 	return socket_has_perm(current, sock, SOCKET__GETOPT);
3190 }
3191 
3192 static int selinux_socket_shutdown(struct socket *sock, int how)
3193 {
3194 	return socket_has_perm(current, sock, SOCKET__SHUTDOWN);
3195 }
3196 
3197 static int selinux_socket_unix_stream_connect(struct socket *sock,
3198 					      struct socket *other,
3199 					      struct sock *newsk)
3200 {
3201 	struct sk_security_struct *ssec;
3202 	struct inode_security_struct *isec;
3203 	struct inode_security_struct *other_isec;
3204 	struct avc_audit_data ad;
3205 	int err;
3206 
3207 	err = secondary_ops->unix_stream_connect(sock, other, newsk);
3208 	if (err)
3209 		return err;
3210 
3211 	isec = SOCK_INODE(sock)->i_security;
3212 	other_isec = SOCK_INODE(other)->i_security;
3213 
3214 	AVC_AUDIT_DATA_INIT(&ad,NET);
3215 	ad.u.net.sk = other->sk;
3216 
3217 	err = avc_has_perm(isec->sid, other_isec->sid,
3218 			   isec->sclass,
3219 			   UNIX_STREAM_SOCKET__CONNECTTO, &ad);
3220 	if (err)
3221 		return err;
3222 
3223 	/* connecting socket */
3224 	ssec = sock->sk->sk_security;
3225 	ssec->peer_sid = other_isec->sid;
3226 
3227 	/* server child socket */
3228 	ssec = newsk->sk_security;
3229 	ssec->peer_sid = isec->sid;
3230 
3231 	return 0;
3232 }
3233 
3234 static int selinux_socket_unix_may_send(struct socket *sock,
3235 					struct socket *other)
3236 {
3237 	struct inode_security_struct *isec;
3238 	struct inode_security_struct *other_isec;
3239 	struct avc_audit_data ad;
3240 	int err;
3241 
3242 	isec = SOCK_INODE(sock)->i_security;
3243 	other_isec = SOCK_INODE(other)->i_security;
3244 
3245 	AVC_AUDIT_DATA_INIT(&ad,NET);
3246 	ad.u.net.sk = other->sk;
3247 
3248 	err = avc_has_perm(isec->sid, other_isec->sid,
3249 			   isec->sclass, SOCKET__SENDTO, &ad);
3250 	if (err)
3251 		return err;
3252 
3253 	return 0;
3254 }
3255 
3256 static int selinux_socket_sock_rcv_skb(struct sock *sk, struct sk_buff *skb)
3257 {
3258 	u16 family;
3259 	char *addrp;
3260 	int len, err = 0;
3261 	u32 netif_perm, node_perm, node_sid, if_sid, recv_perm = 0;
3262 	u32 sock_sid = 0;
3263 	u16 sock_class = 0;
3264 	struct socket *sock;
3265 	struct net_device *dev;
3266 	struct avc_audit_data ad;
3267 
3268 	family = sk->sk_family;
3269 	if (family != PF_INET && family != PF_INET6)
3270 		goto out;
3271 
3272 	/* Handle mapped IPv4 packets arriving via IPv6 sockets */
3273 	if (family == PF_INET6 && skb->protocol == ntohs(ETH_P_IP))
3274 		family = PF_INET;
3275 
3276  	read_lock_bh(&sk->sk_callback_lock);
3277  	sock = sk->sk_socket;
3278  	if (sock) {
3279  		struct inode *inode;
3280  		inode = SOCK_INODE(sock);
3281  		if (inode) {
3282  			struct inode_security_struct *isec;
3283  			isec = inode->i_security;
3284  			sock_sid = isec->sid;
3285  			sock_class = isec->sclass;
3286  		}
3287  	}
3288  	read_unlock_bh(&sk->sk_callback_lock);
3289  	if (!sock_sid)
3290   		goto out;
3291 
3292 	dev = skb->dev;
3293 	if (!dev)
3294 		goto out;
3295 
3296 	err = sel_netif_sids(dev, &if_sid, NULL);
3297 	if (err)
3298 		goto out;
3299 
3300 	switch (sock_class) {
3301 	case SECCLASS_UDP_SOCKET:
3302 		netif_perm = NETIF__UDP_RECV;
3303 		node_perm = NODE__UDP_RECV;
3304 		recv_perm = UDP_SOCKET__RECV_MSG;
3305 		break;
3306 
3307 	case SECCLASS_TCP_SOCKET:
3308 		netif_perm = NETIF__TCP_RECV;
3309 		node_perm = NODE__TCP_RECV;
3310 		recv_perm = TCP_SOCKET__RECV_MSG;
3311 		break;
3312 
3313 	default:
3314 		netif_perm = NETIF__RAWIP_RECV;
3315 		node_perm = NODE__RAWIP_RECV;
3316 		break;
3317 	}
3318 
3319 	AVC_AUDIT_DATA_INIT(&ad, NET);
3320 	ad.u.net.netif = dev->name;
3321 	ad.u.net.family = family;
3322 
3323 	err = selinux_parse_skb(skb, &ad, &addrp, &len, 1);
3324 	if (err)
3325 		goto out;
3326 
3327 	err = avc_has_perm(sock_sid, if_sid, SECCLASS_NETIF, netif_perm, &ad);
3328 	if (err)
3329 		goto out;
3330 
3331 	/* Fixme: this lookup is inefficient */
3332 	err = security_node_sid(family, addrp, len, &node_sid);
3333 	if (err)
3334 		goto out;
3335 
3336 	err = avc_has_perm(sock_sid, node_sid, SECCLASS_NODE, node_perm, &ad);
3337 	if (err)
3338 		goto out;
3339 
3340 	if (recv_perm) {
3341 		u32 port_sid;
3342 
3343 		/* Fixme: make this more efficient */
3344 		err = security_port_sid(sk->sk_family, sk->sk_type,
3345 		                        sk->sk_protocol, ntohs(ad.u.net.sport),
3346 		                        &port_sid);
3347 		if (err)
3348 			goto out;
3349 
3350 		err = avc_has_perm(sock_sid, port_sid,
3351 				   sock_class, recv_perm, &ad);
3352 	}
3353 out:
3354 	return err;
3355 }
3356 
3357 static int selinux_socket_getpeersec(struct socket *sock, char __user *optval,
3358 				     int __user *optlen, unsigned len)
3359 {
3360 	int err = 0;
3361 	char *scontext;
3362 	u32 scontext_len;
3363 	struct sk_security_struct *ssec;
3364 	struct inode_security_struct *isec;
3365 
3366 	isec = SOCK_INODE(sock)->i_security;
3367 	if (isec->sclass != SECCLASS_UNIX_STREAM_SOCKET) {
3368 		err = -ENOPROTOOPT;
3369 		goto out;
3370 	}
3371 
3372 	ssec = sock->sk->sk_security;
3373 
3374 	err = security_sid_to_context(ssec->peer_sid, &scontext, &scontext_len);
3375 	if (err)
3376 		goto out;
3377 
3378 	if (scontext_len > len) {
3379 		err = -ERANGE;
3380 		goto out_len;
3381 	}
3382 
3383 	if (copy_to_user(optval, scontext, scontext_len))
3384 		err = -EFAULT;
3385 
3386 out_len:
3387 	if (put_user(scontext_len, optlen))
3388 		err = -EFAULT;
3389 
3390 	kfree(scontext);
3391 out:
3392 	return err;
3393 }
3394 
3395 static int selinux_sk_alloc_security(struct sock *sk, int family, int priority)
3396 {
3397 	return sk_alloc_security(sk, family, priority);
3398 }
3399 
3400 static void selinux_sk_free_security(struct sock *sk)
3401 {
3402 	sk_free_security(sk);
3403 }
3404 
3405 static int selinux_nlmsg_perm(struct sock *sk, struct sk_buff *skb)
3406 {
3407 	int err = 0;
3408 	u32 perm;
3409 	struct nlmsghdr *nlh;
3410 	struct socket *sock = sk->sk_socket;
3411 	struct inode_security_struct *isec = SOCK_INODE(sock)->i_security;
3412 
3413 	if (skb->len < NLMSG_SPACE(0)) {
3414 		err = -EINVAL;
3415 		goto out;
3416 	}
3417 	nlh = (struct nlmsghdr *)skb->data;
3418 
3419 	err = selinux_nlmsg_lookup(isec->sclass, nlh->nlmsg_type, &perm);
3420 	if (err) {
3421 		if (err == -EINVAL) {
3422 			audit_log(current->audit_context,
3423 				  "SELinux:  unrecognized netlink message"
3424 				  " type=%hu for sclass=%hu\n",
3425 				  nlh->nlmsg_type, isec->sclass);
3426 			if (!selinux_enforcing)
3427 				err = 0;
3428 		}
3429 
3430 		/* Ignore */
3431 		if (err == -ENOENT)
3432 			err = 0;
3433 		goto out;
3434 	}
3435 
3436 	err = socket_has_perm(current, sock, perm);
3437 out:
3438 	return err;
3439 }
3440 
3441 #ifdef CONFIG_NETFILTER
3442 
3443 static unsigned int selinux_ip_postroute_last(unsigned int hooknum,
3444                                               struct sk_buff **pskb,
3445                                               const struct net_device *in,
3446                                               const struct net_device *out,
3447                                               int (*okfn)(struct sk_buff *),
3448                                               u16 family)
3449 {
3450 	char *addrp;
3451 	int len, err = NF_ACCEPT;
3452 	u32 netif_perm, node_perm, node_sid, if_sid, send_perm = 0;
3453 	struct sock *sk;
3454 	struct socket *sock;
3455 	struct inode *inode;
3456 	struct sk_buff *skb = *pskb;
3457 	struct inode_security_struct *isec;
3458 	struct avc_audit_data ad;
3459 	struct net_device *dev = (struct net_device *)out;
3460 
3461 	sk = skb->sk;
3462 	if (!sk)
3463 		goto out;
3464 
3465 	sock = sk->sk_socket;
3466 	if (!sock)
3467 		goto out;
3468 
3469 	inode = SOCK_INODE(sock);
3470 	if (!inode)
3471 		goto out;
3472 
3473 	err = sel_netif_sids(dev, &if_sid, NULL);
3474 	if (err)
3475 		goto out;
3476 
3477 	isec = inode->i_security;
3478 
3479 	switch (isec->sclass) {
3480 	case SECCLASS_UDP_SOCKET:
3481 		netif_perm = NETIF__UDP_SEND;
3482 		node_perm = NODE__UDP_SEND;
3483 		send_perm = UDP_SOCKET__SEND_MSG;
3484 		break;
3485 
3486 	case SECCLASS_TCP_SOCKET:
3487 		netif_perm = NETIF__TCP_SEND;
3488 		node_perm = NODE__TCP_SEND;
3489 		send_perm = TCP_SOCKET__SEND_MSG;
3490 		break;
3491 
3492 	default:
3493 		netif_perm = NETIF__RAWIP_SEND;
3494 		node_perm = NODE__RAWIP_SEND;
3495 		break;
3496 	}
3497 
3498 
3499 	AVC_AUDIT_DATA_INIT(&ad, NET);
3500 	ad.u.net.netif = dev->name;
3501 	ad.u.net.family = family;
3502 
3503 	err = selinux_parse_skb(skb, &ad, &addrp,
3504 				&len, 0) ? NF_DROP : NF_ACCEPT;
3505 	if (err != NF_ACCEPT)
3506 		goto out;
3507 
3508 	err = avc_has_perm(isec->sid, if_sid, SECCLASS_NETIF,
3509 	                   netif_perm, &ad) ? NF_DROP : NF_ACCEPT;
3510 	if (err != NF_ACCEPT)
3511 		goto out;
3512 
3513 	/* Fixme: this lookup is inefficient */
3514 	err = security_node_sid(family, addrp, len,
3515 				&node_sid) ? NF_DROP : NF_ACCEPT;
3516 	if (err != NF_ACCEPT)
3517 		goto out;
3518 
3519 	err = avc_has_perm(isec->sid, node_sid, SECCLASS_NODE,
3520 	                   node_perm, &ad) ? NF_DROP : NF_ACCEPT;
3521 	if (err != NF_ACCEPT)
3522 		goto out;
3523 
3524 	if (send_perm) {
3525 		u32 port_sid;
3526 
3527 		/* Fixme: make this more efficient */
3528 		err = security_port_sid(sk->sk_family,
3529 		                        sk->sk_type,
3530 		                        sk->sk_protocol,
3531 		                        ntohs(ad.u.net.dport),
3532 		                        &port_sid) ? NF_DROP : NF_ACCEPT;
3533 		if (err != NF_ACCEPT)
3534 			goto out;
3535 
3536 		err = avc_has_perm(isec->sid, port_sid, isec->sclass,
3537 		                   send_perm, &ad) ? NF_DROP : NF_ACCEPT;
3538 	}
3539 
3540 out:
3541 	return err;
3542 }
3543 
3544 static unsigned int selinux_ipv4_postroute_last(unsigned int hooknum,
3545 						struct sk_buff **pskb,
3546 						const struct net_device *in,
3547 						const struct net_device *out,
3548 						int (*okfn)(struct sk_buff *))
3549 {
3550 	return selinux_ip_postroute_last(hooknum, pskb, in, out, okfn, PF_INET);
3551 }
3552 
3553 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
3554 
3555 static unsigned int selinux_ipv6_postroute_last(unsigned int hooknum,
3556 						struct sk_buff **pskb,
3557 						const struct net_device *in,
3558 						const struct net_device *out,
3559 						int (*okfn)(struct sk_buff *))
3560 {
3561 	return selinux_ip_postroute_last(hooknum, pskb, in, out, okfn, PF_INET6);
3562 }
3563 
3564 #endif	/* IPV6 */
3565 
3566 #endif	/* CONFIG_NETFILTER */
3567 
3568 #else
3569 
3570 static inline int selinux_nlmsg_perm(struct sock *sk, struct sk_buff *skb)
3571 {
3572 	return 0;
3573 }
3574 
3575 #endif	/* CONFIG_SECURITY_NETWORK */
3576 
3577 static int selinux_netlink_send(struct sock *sk, struct sk_buff *skb)
3578 {
3579 	struct task_security_struct *tsec;
3580 	struct av_decision avd;
3581 	int err;
3582 
3583 	err = secondary_ops->netlink_send(sk, skb);
3584 	if (err)
3585 		return err;
3586 
3587 	tsec = current->security;
3588 
3589 	avd.allowed = 0;
3590 	avc_has_perm_noaudit(tsec->sid, tsec->sid,
3591 				SECCLASS_CAPABILITY, ~0, &avd);
3592 	cap_mask(NETLINK_CB(skb).eff_cap, avd.allowed);
3593 
3594 	if (policydb_loaded_version >= POLICYDB_VERSION_NLCLASS)
3595 		err = selinux_nlmsg_perm(sk, skb);
3596 
3597 	return err;
3598 }
3599 
3600 static int selinux_netlink_recv(struct sk_buff *skb)
3601 {
3602 	if (!cap_raised(NETLINK_CB(skb).eff_cap, CAP_NET_ADMIN))
3603 		return -EPERM;
3604 	return 0;
3605 }
3606 
3607 static int ipc_alloc_security(struct task_struct *task,
3608 			      struct kern_ipc_perm *perm,
3609 			      u16 sclass)
3610 {
3611 	struct task_security_struct *tsec = task->security;
3612 	struct ipc_security_struct *isec;
3613 
3614 	isec = kmalloc(sizeof(struct ipc_security_struct), GFP_KERNEL);
3615 	if (!isec)
3616 		return -ENOMEM;
3617 
3618 	memset(isec, 0, sizeof(struct ipc_security_struct));
3619 	isec->magic = SELINUX_MAGIC;
3620 	isec->sclass = sclass;
3621 	isec->ipc_perm = perm;
3622 	if (tsec) {
3623 		isec->sid = tsec->sid;
3624 	} else {
3625 		isec->sid = SECINITSID_UNLABELED;
3626 	}
3627 	perm->security = isec;
3628 
3629 	return 0;
3630 }
3631 
3632 static void ipc_free_security(struct kern_ipc_perm *perm)
3633 {
3634 	struct ipc_security_struct *isec = perm->security;
3635 	if (!isec || isec->magic != SELINUX_MAGIC)
3636 		return;
3637 
3638 	perm->security = NULL;
3639 	kfree(isec);
3640 }
3641 
3642 static int msg_msg_alloc_security(struct msg_msg *msg)
3643 {
3644 	struct msg_security_struct *msec;
3645 
3646 	msec = kmalloc(sizeof(struct msg_security_struct), GFP_KERNEL);
3647 	if (!msec)
3648 		return -ENOMEM;
3649 
3650 	memset(msec, 0, sizeof(struct msg_security_struct));
3651 	msec->magic = SELINUX_MAGIC;
3652 	msec->msg = msg;
3653 	msec->sid = SECINITSID_UNLABELED;
3654 	msg->security = msec;
3655 
3656 	return 0;
3657 }
3658 
3659 static void msg_msg_free_security(struct msg_msg *msg)
3660 {
3661 	struct msg_security_struct *msec = msg->security;
3662 	if (!msec || msec->magic != SELINUX_MAGIC)
3663 		return;
3664 
3665 	msg->security = NULL;
3666 	kfree(msec);
3667 }
3668 
3669 static int ipc_has_perm(struct kern_ipc_perm *ipc_perms,
3670 			u32 perms)
3671 {
3672 	struct task_security_struct *tsec;
3673 	struct ipc_security_struct *isec;
3674 	struct avc_audit_data ad;
3675 
3676 	tsec = current->security;
3677 	isec = ipc_perms->security;
3678 
3679 	AVC_AUDIT_DATA_INIT(&ad, IPC);
3680 	ad.u.ipc_id = ipc_perms->key;
3681 
3682 	return avc_has_perm(tsec->sid, isec->sid, isec->sclass, perms, &ad);
3683 }
3684 
3685 static int selinux_msg_msg_alloc_security(struct msg_msg *msg)
3686 {
3687 	return msg_msg_alloc_security(msg);
3688 }
3689 
3690 static void selinux_msg_msg_free_security(struct msg_msg *msg)
3691 {
3692 	msg_msg_free_security(msg);
3693 }
3694 
3695 /* message queue security operations */
3696 static int selinux_msg_queue_alloc_security(struct msg_queue *msq)
3697 {
3698 	struct task_security_struct *tsec;
3699 	struct ipc_security_struct *isec;
3700 	struct avc_audit_data ad;
3701 	int rc;
3702 
3703 	rc = ipc_alloc_security(current, &msq->q_perm, SECCLASS_MSGQ);
3704 	if (rc)
3705 		return rc;
3706 
3707 	tsec = current->security;
3708 	isec = msq->q_perm.security;
3709 
3710 	AVC_AUDIT_DATA_INIT(&ad, IPC);
3711  	ad.u.ipc_id = msq->q_perm.key;
3712 
3713 	rc = avc_has_perm(tsec->sid, isec->sid, SECCLASS_MSGQ,
3714 			  MSGQ__CREATE, &ad);
3715 	if (rc) {
3716 		ipc_free_security(&msq->q_perm);
3717 		return rc;
3718 	}
3719 	return 0;
3720 }
3721 
3722 static void selinux_msg_queue_free_security(struct msg_queue *msq)
3723 {
3724 	ipc_free_security(&msq->q_perm);
3725 }
3726 
3727 static int selinux_msg_queue_associate(struct msg_queue *msq, int msqflg)
3728 {
3729 	struct task_security_struct *tsec;
3730 	struct ipc_security_struct *isec;
3731 	struct avc_audit_data ad;
3732 
3733 	tsec = current->security;
3734 	isec = msq->q_perm.security;
3735 
3736 	AVC_AUDIT_DATA_INIT(&ad, IPC);
3737 	ad.u.ipc_id = msq->q_perm.key;
3738 
3739 	return avc_has_perm(tsec->sid, isec->sid, SECCLASS_MSGQ,
3740 			    MSGQ__ASSOCIATE, &ad);
3741 }
3742 
3743 static int selinux_msg_queue_msgctl(struct msg_queue *msq, int cmd)
3744 {
3745 	int err;
3746 	int perms;
3747 
3748 	switch(cmd) {
3749 	case IPC_INFO:
3750 	case MSG_INFO:
3751 		/* No specific object, just general system-wide information. */
3752 		return task_has_system(current, SYSTEM__IPC_INFO);
3753 	case IPC_STAT:
3754 	case MSG_STAT:
3755 		perms = MSGQ__GETATTR | MSGQ__ASSOCIATE;
3756 		break;
3757 	case IPC_SET:
3758 		perms = MSGQ__SETATTR;
3759 		break;
3760 	case IPC_RMID:
3761 		perms = MSGQ__DESTROY;
3762 		break;
3763 	default:
3764 		return 0;
3765 	}
3766 
3767 	err = ipc_has_perm(&msq->q_perm, perms);
3768 	return err;
3769 }
3770 
3771 static int selinux_msg_queue_msgsnd(struct msg_queue *msq, struct msg_msg *msg, int msqflg)
3772 {
3773 	struct task_security_struct *tsec;
3774 	struct ipc_security_struct *isec;
3775 	struct msg_security_struct *msec;
3776 	struct avc_audit_data ad;
3777 	int rc;
3778 
3779 	tsec = current->security;
3780 	isec = msq->q_perm.security;
3781 	msec = msg->security;
3782 
3783 	/*
3784 	 * First time through, need to assign label to the message
3785 	 */
3786 	if (msec->sid == SECINITSID_UNLABELED) {
3787 		/*
3788 		 * Compute new sid based on current process and
3789 		 * message queue this message will be stored in
3790 		 */
3791 		rc = security_transition_sid(tsec->sid,
3792 					     isec->sid,
3793 					     SECCLASS_MSG,
3794 					     &msec->sid);
3795 		if (rc)
3796 			return rc;
3797 	}
3798 
3799 	AVC_AUDIT_DATA_INIT(&ad, IPC);
3800 	ad.u.ipc_id = msq->q_perm.key;
3801 
3802 	/* Can this process write to the queue? */
3803 	rc = avc_has_perm(tsec->sid, isec->sid, SECCLASS_MSGQ,
3804 			  MSGQ__WRITE, &ad);
3805 	if (!rc)
3806 		/* Can this process send the message */
3807 		rc = avc_has_perm(tsec->sid, msec->sid,
3808 				  SECCLASS_MSG, MSG__SEND, &ad);
3809 	if (!rc)
3810 		/* Can the message be put in the queue? */
3811 		rc = avc_has_perm(msec->sid, isec->sid,
3812 				  SECCLASS_MSGQ, MSGQ__ENQUEUE, &ad);
3813 
3814 	return rc;
3815 }
3816 
3817 static int selinux_msg_queue_msgrcv(struct msg_queue *msq, struct msg_msg *msg,
3818 				    struct task_struct *target,
3819 				    long type, int mode)
3820 {
3821 	struct task_security_struct *tsec;
3822 	struct ipc_security_struct *isec;
3823 	struct msg_security_struct *msec;
3824 	struct avc_audit_data ad;
3825 	int rc;
3826 
3827 	tsec = target->security;
3828 	isec = msq->q_perm.security;
3829 	msec = msg->security;
3830 
3831 	AVC_AUDIT_DATA_INIT(&ad, IPC);
3832  	ad.u.ipc_id = msq->q_perm.key;
3833 
3834 	rc = avc_has_perm(tsec->sid, isec->sid,
3835 			  SECCLASS_MSGQ, MSGQ__READ, &ad);
3836 	if (!rc)
3837 		rc = avc_has_perm(tsec->sid, msec->sid,
3838 				  SECCLASS_MSG, MSG__RECEIVE, &ad);
3839 	return rc;
3840 }
3841 
3842 /* Shared Memory security operations */
3843 static int selinux_shm_alloc_security(struct shmid_kernel *shp)
3844 {
3845 	struct task_security_struct *tsec;
3846 	struct ipc_security_struct *isec;
3847 	struct avc_audit_data ad;
3848 	int rc;
3849 
3850 	rc = ipc_alloc_security(current, &shp->shm_perm, SECCLASS_SHM);
3851 	if (rc)
3852 		return rc;
3853 
3854 	tsec = current->security;
3855 	isec = shp->shm_perm.security;
3856 
3857 	AVC_AUDIT_DATA_INIT(&ad, IPC);
3858  	ad.u.ipc_id = shp->shm_perm.key;
3859 
3860 	rc = avc_has_perm(tsec->sid, isec->sid, SECCLASS_SHM,
3861 			  SHM__CREATE, &ad);
3862 	if (rc) {
3863 		ipc_free_security(&shp->shm_perm);
3864 		return rc;
3865 	}
3866 	return 0;
3867 }
3868 
3869 static void selinux_shm_free_security(struct shmid_kernel *shp)
3870 {
3871 	ipc_free_security(&shp->shm_perm);
3872 }
3873 
3874 static int selinux_shm_associate(struct shmid_kernel *shp, int shmflg)
3875 {
3876 	struct task_security_struct *tsec;
3877 	struct ipc_security_struct *isec;
3878 	struct avc_audit_data ad;
3879 
3880 	tsec = current->security;
3881 	isec = shp->shm_perm.security;
3882 
3883 	AVC_AUDIT_DATA_INIT(&ad, IPC);
3884 	ad.u.ipc_id = shp->shm_perm.key;
3885 
3886 	return avc_has_perm(tsec->sid, isec->sid, SECCLASS_SHM,
3887 			    SHM__ASSOCIATE, &ad);
3888 }
3889 
3890 /* Note, at this point, shp is locked down */
3891 static int selinux_shm_shmctl(struct shmid_kernel *shp, int cmd)
3892 {
3893 	int perms;
3894 	int err;
3895 
3896 	switch(cmd) {
3897 	case IPC_INFO:
3898 	case SHM_INFO:
3899 		/* No specific object, just general system-wide information. */
3900 		return task_has_system(current, SYSTEM__IPC_INFO);
3901 	case IPC_STAT:
3902 	case SHM_STAT:
3903 		perms = SHM__GETATTR | SHM__ASSOCIATE;
3904 		break;
3905 	case IPC_SET:
3906 		perms = SHM__SETATTR;
3907 		break;
3908 	case SHM_LOCK:
3909 	case SHM_UNLOCK:
3910 		perms = SHM__LOCK;
3911 		break;
3912 	case IPC_RMID:
3913 		perms = SHM__DESTROY;
3914 		break;
3915 	default:
3916 		return 0;
3917 	}
3918 
3919 	err = ipc_has_perm(&shp->shm_perm, perms);
3920 	return err;
3921 }
3922 
3923 static int selinux_shm_shmat(struct shmid_kernel *shp,
3924 			     char __user *shmaddr, int shmflg)
3925 {
3926 	u32 perms;
3927 	int rc;
3928 
3929 	rc = secondary_ops->shm_shmat(shp, shmaddr, shmflg);
3930 	if (rc)
3931 		return rc;
3932 
3933 	if (shmflg & SHM_RDONLY)
3934 		perms = SHM__READ;
3935 	else
3936 		perms = SHM__READ | SHM__WRITE;
3937 
3938 	return ipc_has_perm(&shp->shm_perm, perms);
3939 }
3940 
3941 /* Semaphore security operations */
3942 static int selinux_sem_alloc_security(struct sem_array *sma)
3943 {
3944 	struct task_security_struct *tsec;
3945 	struct ipc_security_struct *isec;
3946 	struct avc_audit_data ad;
3947 	int rc;
3948 
3949 	rc = ipc_alloc_security(current, &sma->sem_perm, SECCLASS_SEM);
3950 	if (rc)
3951 		return rc;
3952 
3953 	tsec = current->security;
3954 	isec = sma->sem_perm.security;
3955 
3956 	AVC_AUDIT_DATA_INIT(&ad, IPC);
3957  	ad.u.ipc_id = sma->sem_perm.key;
3958 
3959 	rc = avc_has_perm(tsec->sid, isec->sid, SECCLASS_SEM,
3960 			  SEM__CREATE, &ad);
3961 	if (rc) {
3962 		ipc_free_security(&sma->sem_perm);
3963 		return rc;
3964 	}
3965 	return 0;
3966 }
3967 
3968 static void selinux_sem_free_security(struct sem_array *sma)
3969 {
3970 	ipc_free_security(&sma->sem_perm);
3971 }
3972 
3973 static int selinux_sem_associate(struct sem_array *sma, int semflg)
3974 {
3975 	struct task_security_struct *tsec;
3976 	struct ipc_security_struct *isec;
3977 	struct avc_audit_data ad;
3978 
3979 	tsec = current->security;
3980 	isec = sma->sem_perm.security;
3981 
3982 	AVC_AUDIT_DATA_INIT(&ad, IPC);
3983 	ad.u.ipc_id = sma->sem_perm.key;
3984 
3985 	return avc_has_perm(tsec->sid, isec->sid, SECCLASS_SEM,
3986 			    SEM__ASSOCIATE, &ad);
3987 }
3988 
3989 /* Note, at this point, sma is locked down */
3990 static int selinux_sem_semctl(struct sem_array *sma, int cmd)
3991 {
3992 	int err;
3993 	u32 perms;
3994 
3995 	switch(cmd) {
3996 	case IPC_INFO:
3997 	case SEM_INFO:
3998 		/* No specific object, just general system-wide information. */
3999 		return task_has_system(current, SYSTEM__IPC_INFO);
4000 	case GETPID:
4001 	case GETNCNT:
4002 	case GETZCNT:
4003 		perms = SEM__GETATTR;
4004 		break;
4005 	case GETVAL:
4006 	case GETALL:
4007 		perms = SEM__READ;
4008 		break;
4009 	case SETVAL:
4010 	case SETALL:
4011 		perms = SEM__WRITE;
4012 		break;
4013 	case IPC_RMID:
4014 		perms = SEM__DESTROY;
4015 		break;
4016 	case IPC_SET:
4017 		perms = SEM__SETATTR;
4018 		break;
4019 	case IPC_STAT:
4020 	case SEM_STAT:
4021 		perms = SEM__GETATTR | SEM__ASSOCIATE;
4022 		break;
4023 	default:
4024 		return 0;
4025 	}
4026 
4027 	err = ipc_has_perm(&sma->sem_perm, perms);
4028 	return err;
4029 }
4030 
4031 static int selinux_sem_semop(struct sem_array *sma,
4032 			     struct sembuf *sops, unsigned nsops, int alter)
4033 {
4034 	u32 perms;
4035 
4036 	if (alter)
4037 		perms = SEM__READ | SEM__WRITE;
4038 	else
4039 		perms = SEM__READ;
4040 
4041 	return ipc_has_perm(&sma->sem_perm, perms);
4042 }
4043 
4044 static int selinux_ipc_permission(struct kern_ipc_perm *ipcp, short flag)
4045 {
4046 	u32 av = 0;
4047 
4048 	av = 0;
4049 	if (flag & S_IRUGO)
4050 		av |= IPC__UNIX_READ;
4051 	if (flag & S_IWUGO)
4052 		av |= IPC__UNIX_WRITE;
4053 
4054 	if (av == 0)
4055 		return 0;
4056 
4057 	return ipc_has_perm(ipcp, av);
4058 }
4059 
4060 /* module stacking operations */
4061 static int selinux_register_security (const char *name, struct security_operations *ops)
4062 {
4063 	if (secondary_ops != original_ops) {
4064 		printk(KERN_INFO "%s:  There is already a secondary security "
4065 		       "module registered.\n", __FUNCTION__);
4066 		return -EINVAL;
4067  	}
4068 
4069 	secondary_ops = ops;
4070 
4071 	printk(KERN_INFO "%s:  Registering secondary module %s\n",
4072 	       __FUNCTION__,
4073 	       name);
4074 
4075 	return 0;
4076 }
4077 
4078 static int selinux_unregister_security (const char *name, struct security_operations *ops)
4079 {
4080 	if (ops != secondary_ops) {
4081 		printk (KERN_INFO "%s:  trying to unregister a security module "
4082 		        "that is not registered.\n", __FUNCTION__);
4083 		return -EINVAL;
4084 	}
4085 
4086 	secondary_ops = original_ops;
4087 
4088 	return 0;
4089 }
4090 
4091 static void selinux_d_instantiate (struct dentry *dentry, struct inode *inode)
4092 {
4093 	if (inode)
4094 		inode_doinit_with_dentry(inode, dentry);
4095 }
4096 
4097 static int selinux_getprocattr(struct task_struct *p,
4098 			       char *name, void *value, size_t size)
4099 {
4100 	struct task_security_struct *tsec;
4101 	u32 sid, len;
4102 	char *context;
4103 	int error;
4104 
4105 	if (current != p) {
4106 		error = task_has_perm(current, p, PROCESS__GETATTR);
4107 		if (error)
4108 			return error;
4109 	}
4110 
4111 	if (!size)
4112 		return -ERANGE;
4113 
4114 	tsec = p->security;
4115 
4116 	if (!strcmp(name, "current"))
4117 		sid = tsec->sid;
4118 	else if (!strcmp(name, "prev"))
4119 		sid = tsec->osid;
4120 	else if (!strcmp(name, "exec"))
4121 		sid = tsec->exec_sid;
4122 	else if (!strcmp(name, "fscreate"))
4123 		sid = tsec->create_sid;
4124 	else
4125 		return -EINVAL;
4126 
4127 	if (!sid)
4128 		return 0;
4129 
4130 	error = security_sid_to_context(sid, &context, &len);
4131 	if (error)
4132 		return error;
4133 	if (len > size) {
4134 		kfree(context);
4135 		return -ERANGE;
4136 	}
4137 	memcpy(value, context, len);
4138 	kfree(context);
4139 	return len;
4140 }
4141 
4142 static int selinux_setprocattr(struct task_struct *p,
4143 			       char *name, void *value, size_t size)
4144 {
4145 	struct task_security_struct *tsec;
4146 	u32 sid = 0;
4147 	int error;
4148 	char *str = value;
4149 
4150 	if (current != p) {
4151 		/* SELinux only allows a process to change its own
4152 		   security attributes. */
4153 		return -EACCES;
4154 	}
4155 
4156 	/*
4157 	 * Basic control over ability to set these attributes at all.
4158 	 * current == p, but we'll pass them separately in case the
4159 	 * above restriction is ever removed.
4160 	 */
4161 	if (!strcmp(name, "exec"))
4162 		error = task_has_perm(current, p, PROCESS__SETEXEC);
4163 	else if (!strcmp(name, "fscreate"))
4164 		error = task_has_perm(current, p, PROCESS__SETFSCREATE);
4165 	else if (!strcmp(name, "current"))
4166 		error = task_has_perm(current, p, PROCESS__SETCURRENT);
4167 	else
4168 		error = -EINVAL;
4169 	if (error)
4170 		return error;
4171 
4172 	/* Obtain a SID for the context, if one was specified. */
4173 	if (size && str[1] && str[1] != '\n') {
4174 		if (str[size-1] == '\n') {
4175 			str[size-1] = 0;
4176 			size--;
4177 		}
4178 		error = security_context_to_sid(value, size, &sid);
4179 		if (error)
4180 			return error;
4181 	}
4182 
4183 	/* Permission checking based on the specified context is
4184 	   performed during the actual operation (execve,
4185 	   open/mkdir/...), when we know the full context of the
4186 	   operation.  See selinux_bprm_set_security for the execve
4187 	   checks and may_create for the file creation checks. The
4188 	   operation will then fail if the context is not permitted. */
4189 	tsec = p->security;
4190 	if (!strcmp(name, "exec"))
4191 		tsec->exec_sid = sid;
4192 	else if (!strcmp(name, "fscreate"))
4193 		tsec->create_sid = sid;
4194 	else if (!strcmp(name, "current")) {
4195 		struct av_decision avd;
4196 
4197 		if (sid == 0)
4198 			return -EINVAL;
4199 
4200 		/* Only allow single threaded processes to change context */
4201 		if (atomic_read(&p->mm->mm_users) != 1) {
4202 			struct task_struct *g, *t;
4203 			struct mm_struct *mm = p->mm;
4204 			read_lock(&tasklist_lock);
4205 			do_each_thread(g, t)
4206 				if (t->mm == mm && t != p) {
4207 					read_unlock(&tasklist_lock);
4208 					return -EPERM;
4209 				}
4210 			while_each_thread(g, t);
4211 			read_unlock(&tasklist_lock);
4212                 }
4213 
4214 		/* Check permissions for the transition. */
4215 		error = avc_has_perm(tsec->sid, sid, SECCLASS_PROCESS,
4216 		                     PROCESS__DYNTRANSITION, NULL);
4217 		if (error)
4218 			return error;
4219 
4220 		/* Check for ptracing, and update the task SID if ok.
4221 		   Otherwise, leave SID unchanged and fail. */
4222 		task_lock(p);
4223 		if (p->ptrace & PT_PTRACED) {
4224 			error = avc_has_perm_noaudit(tsec->ptrace_sid, sid,
4225 						     SECCLASS_PROCESS,
4226 						     PROCESS__PTRACE, &avd);
4227 			if (!error)
4228 				tsec->sid = sid;
4229 			task_unlock(p);
4230 			avc_audit(tsec->ptrace_sid, sid, SECCLASS_PROCESS,
4231 				  PROCESS__PTRACE, &avd, error, NULL);
4232 			if (error)
4233 				return error;
4234 		} else {
4235 			tsec->sid = sid;
4236 			task_unlock(p);
4237 		}
4238 	}
4239 	else
4240 		return -EINVAL;
4241 
4242 	return size;
4243 }
4244 
4245 static struct security_operations selinux_ops = {
4246 	.ptrace =			selinux_ptrace,
4247 	.capget =			selinux_capget,
4248 	.capset_check =			selinux_capset_check,
4249 	.capset_set =			selinux_capset_set,
4250 	.sysctl =			selinux_sysctl,
4251 	.capable =			selinux_capable,
4252 	.quotactl =			selinux_quotactl,
4253 	.quota_on =			selinux_quota_on,
4254 	.syslog =			selinux_syslog,
4255 	.vm_enough_memory =		selinux_vm_enough_memory,
4256 
4257 	.netlink_send =			selinux_netlink_send,
4258         .netlink_recv =			selinux_netlink_recv,
4259 
4260 	.bprm_alloc_security =		selinux_bprm_alloc_security,
4261 	.bprm_free_security =		selinux_bprm_free_security,
4262 	.bprm_apply_creds =		selinux_bprm_apply_creds,
4263 	.bprm_post_apply_creds =	selinux_bprm_post_apply_creds,
4264 	.bprm_set_security =		selinux_bprm_set_security,
4265 	.bprm_check_security =		selinux_bprm_check_security,
4266 	.bprm_secureexec =		selinux_bprm_secureexec,
4267 
4268 	.sb_alloc_security =		selinux_sb_alloc_security,
4269 	.sb_free_security =		selinux_sb_free_security,
4270 	.sb_copy_data =			selinux_sb_copy_data,
4271 	.sb_kern_mount =	        selinux_sb_kern_mount,
4272 	.sb_statfs =			selinux_sb_statfs,
4273 	.sb_mount =			selinux_mount,
4274 	.sb_umount =			selinux_umount,
4275 
4276 	.inode_alloc_security =		selinux_inode_alloc_security,
4277 	.inode_free_security =		selinux_inode_free_security,
4278 	.inode_create =			selinux_inode_create,
4279 	.inode_post_create =		selinux_inode_post_create,
4280 	.inode_link =			selinux_inode_link,
4281 	.inode_post_link =		selinux_inode_post_link,
4282 	.inode_unlink =			selinux_inode_unlink,
4283 	.inode_symlink =		selinux_inode_symlink,
4284 	.inode_post_symlink =		selinux_inode_post_symlink,
4285 	.inode_mkdir =			selinux_inode_mkdir,
4286 	.inode_post_mkdir =		selinux_inode_post_mkdir,
4287 	.inode_rmdir =			selinux_inode_rmdir,
4288 	.inode_mknod =			selinux_inode_mknod,
4289 	.inode_post_mknod =		selinux_inode_post_mknod,
4290 	.inode_rename =			selinux_inode_rename,
4291 	.inode_post_rename =		selinux_inode_post_rename,
4292 	.inode_readlink =		selinux_inode_readlink,
4293 	.inode_follow_link =		selinux_inode_follow_link,
4294 	.inode_permission =		selinux_inode_permission,
4295 	.inode_setattr =		selinux_inode_setattr,
4296 	.inode_getattr =		selinux_inode_getattr,
4297 	.inode_setxattr =		selinux_inode_setxattr,
4298 	.inode_post_setxattr =		selinux_inode_post_setxattr,
4299 	.inode_getxattr =		selinux_inode_getxattr,
4300 	.inode_listxattr =		selinux_inode_listxattr,
4301 	.inode_removexattr =		selinux_inode_removexattr,
4302 	.inode_getsecurity =            selinux_inode_getsecurity,
4303 	.inode_setsecurity =            selinux_inode_setsecurity,
4304 	.inode_listsecurity =           selinux_inode_listsecurity,
4305 
4306 	.file_permission =		selinux_file_permission,
4307 	.file_alloc_security =		selinux_file_alloc_security,
4308 	.file_free_security =		selinux_file_free_security,
4309 	.file_ioctl =			selinux_file_ioctl,
4310 	.file_mmap =			selinux_file_mmap,
4311 	.file_mprotect =		selinux_file_mprotect,
4312 	.file_lock =			selinux_file_lock,
4313 	.file_fcntl =			selinux_file_fcntl,
4314 	.file_set_fowner =		selinux_file_set_fowner,
4315 	.file_send_sigiotask =		selinux_file_send_sigiotask,
4316 	.file_receive =			selinux_file_receive,
4317 
4318 	.task_create =			selinux_task_create,
4319 	.task_alloc_security =		selinux_task_alloc_security,
4320 	.task_free_security =		selinux_task_free_security,
4321 	.task_setuid =			selinux_task_setuid,
4322 	.task_post_setuid =		selinux_task_post_setuid,
4323 	.task_setgid =			selinux_task_setgid,
4324 	.task_setpgid =			selinux_task_setpgid,
4325 	.task_getpgid =			selinux_task_getpgid,
4326 	.task_getsid =		        selinux_task_getsid,
4327 	.task_setgroups =		selinux_task_setgroups,
4328 	.task_setnice =			selinux_task_setnice,
4329 	.task_setrlimit =		selinux_task_setrlimit,
4330 	.task_setscheduler =		selinux_task_setscheduler,
4331 	.task_getscheduler =		selinux_task_getscheduler,
4332 	.task_kill =			selinux_task_kill,
4333 	.task_wait =			selinux_task_wait,
4334 	.task_prctl =			selinux_task_prctl,
4335 	.task_reparent_to_init =	selinux_task_reparent_to_init,
4336 	.task_to_inode =                selinux_task_to_inode,
4337 
4338 	.ipc_permission =		selinux_ipc_permission,
4339 
4340 	.msg_msg_alloc_security =	selinux_msg_msg_alloc_security,
4341 	.msg_msg_free_security =	selinux_msg_msg_free_security,
4342 
4343 	.msg_queue_alloc_security =	selinux_msg_queue_alloc_security,
4344 	.msg_queue_free_security =	selinux_msg_queue_free_security,
4345 	.msg_queue_associate =		selinux_msg_queue_associate,
4346 	.msg_queue_msgctl =		selinux_msg_queue_msgctl,
4347 	.msg_queue_msgsnd =		selinux_msg_queue_msgsnd,
4348 	.msg_queue_msgrcv =		selinux_msg_queue_msgrcv,
4349 
4350 	.shm_alloc_security =		selinux_shm_alloc_security,
4351 	.shm_free_security =		selinux_shm_free_security,
4352 	.shm_associate =		selinux_shm_associate,
4353 	.shm_shmctl =			selinux_shm_shmctl,
4354 	.shm_shmat =			selinux_shm_shmat,
4355 
4356 	.sem_alloc_security = 		selinux_sem_alloc_security,
4357 	.sem_free_security =  		selinux_sem_free_security,
4358 	.sem_associate =		selinux_sem_associate,
4359 	.sem_semctl =			selinux_sem_semctl,
4360 	.sem_semop =			selinux_sem_semop,
4361 
4362 	.register_security =		selinux_register_security,
4363 	.unregister_security =		selinux_unregister_security,
4364 
4365 	.d_instantiate =                selinux_d_instantiate,
4366 
4367 	.getprocattr =                  selinux_getprocattr,
4368 	.setprocattr =                  selinux_setprocattr,
4369 
4370 #ifdef CONFIG_SECURITY_NETWORK
4371         .unix_stream_connect =		selinux_socket_unix_stream_connect,
4372 	.unix_may_send =		selinux_socket_unix_may_send,
4373 
4374 	.socket_create =		selinux_socket_create,
4375 	.socket_post_create =		selinux_socket_post_create,
4376 	.socket_bind =			selinux_socket_bind,
4377 	.socket_connect =		selinux_socket_connect,
4378 	.socket_listen =		selinux_socket_listen,
4379 	.socket_accept =		selinux_socket_accept,
4380 	.socket_sendmsg =		selinux_socket_sendmsg,
4381 	.socket_recvmsg =		selinux_socket_recvmsg,
4382 	.socket_getsockname =		selinux_socket_getsockname,
4383 	.socket_getpeername =		selinux_socket_getpeername,
4384 	.socket_getsockopt =		selinux_socket_getsockopt,
4385 	.socket_setsockopt =		selinux_socket_setsockopt,
4386 	.socket_shutdown =		selinux_socket_shutdown,
4387 	.socket_sock_rcv_skb =		selinux_socket_sock_rcv_skb,
4388 	.socket_getpeersec =		selinux_socket_getpeersec,
4389 	.sk_alloc_security =		selinux_sk_alloc_security,
4390 	.sk_free_security =		selinux_sk_free_security,
4391 #endif
4392 };
4393 
4394 static __init int selinux_init(void)
4395 {
4396 	struct task_security_struct *tsec;
4397 
4398 	if (!selinux_enabled) {
4399 		printk(KERN_INFO "SELinux:  Disabled at boot.\n");
4400 		return 0;
4401 	}
4402 
4403 	printk(KERN_INFO "SELinux:  Initializing.\n");
4404 
4405 	/* Set the security state for the initial task. */
4406 	if (task_alloc_security(current))
4407 		panic("SELinux:  Failed to initialize initial task.\n");
4408 	tsec = current->security;
4409 	tsec->osid = tsec->sid = SECINITSID_KERNEL;
4410 
4411 	avc_init();
4412 
4413 	original_ops = secondary_ops = security_ops;
4414 	if (!secondary_ops)
4415 		panic ("SELinux: No initial security operations\n");
4416 	if (register_security (&selinux_ops))
4417 		panic("SELinux: Unable to register with kernel.\n");
4418 
4419 	if (selinux_enforcing) {
4420 		printk(KERN_INFO "SELinux:  Starting in enforcing mode\n");
4421 	} else {
4422 		printk(KERN_INFO "SELinux:  Starting in permissive mode\n");
4423 	}
4424 	return 0;
4425 }
4426 
4427 void selinux_complete_init(void)
4428 {
4429 	printk(KERN_INFO "SELinux:  Completing initialization.\n");
4430 
4431 	/* Set up any superblocks initialized prior to the policy load. */
4432 	printk(KERN_INFO "SELinux:  Setting up existing superblocks.\n");
4433 	spin_lock(&sb_security_lock);
4434 next_sb:
4435 	if (!list_empty(&superblock_security_head)) {
4436 		struct superblock_security_struct *sbsec =
4437 				list_entry(superblock_security_head.next,
4438 				           struct superblock_security_struct,
4439 				           list);
4440 		struct super_block *sb = sbsec->sb;
4441 		spin_lock(&sb_lock);
4442 		sb->s_count++;
4443 		spin_unlock(&sb_lock);
4444 		spin_unlock(&sb_security_lock);
4445 		down_read(&sb->s_umount);
4446 		if (sb->s_root)
4447 			superblock_doinit(sb, NULL);
4448 		drop_super(sb);
4449 		spin_lock(&sb_security_lock);
4450 		list_del_init(&sbsec->list);
4451 		goto next_sb;
4452 	}
4453 	spin_unlock(&sb_security_lock);
4454 }
4455 
4456 /* SELinux requires early initialization in order to label
4457    all processes and objects when they are created. */
4458 security_initcall(selinux_init);
4459 
4460 #if defined(CONFIG_SECURITY_NETWORK) && defined(CONFIG_NETFILTER)
4461 
4462 static struct nf_hook_ops selinux_ipv4_op = {
4463 	.hook =		selinux_ipv4_postroute_last,
4464 	.owner =	THIS_MODULE,
4465 	.pf =		PF_INET,
4466 	.hooknum =	NF_IP_POST_ROUTING,
4467 	.priority =	NF_IP_PRI_SELINUX_LAST,
4468 };
4469 
4470 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
4471 
4472 static struct nf_hook_ops selinux_ipv6_op = {
4473 	.hook =		selinux_ipv6_postroute_last,
4474 	.owner =	THIS_MODULE,
4475 	.pf =		PF_INET6,
4476 	.hooknum =	NF_IP6_POST_ROUTING,
4477 	.priority =	NF_IP6_PRI_SELINUX_LAST,
4478 };
4479 
4480 #endif	/* IPV6 */
4481 
4482 static int __init selinux_nf_ip_init(void)
4483 {
4484 	int err = 0;
4485 
4486 	if (!selinux_enabled)
4487 		goto out;
4488 
4489 	printk(KERN_INFO "SELinux:  Registering netfilter hooks\n");
4490 
4491 	err = nf_register_hook(&selinux_ipv4_op);
4492 	if (err)
4493 		panic("SELinux: nf_register_hook for IPv4: error %d\n", err);
4494 
4495 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
4496 
4497 	err = nf_register_hook(&selinux_ipv6_op);
4498 	if (err)
4499 		panic("SELinux: nf_register_hook for IPv6: error %d\n", err);
4500 
4501 #endif	/* IPV6 */
4502 out:
4503 	return err;
4504 }
4505 
4506 __initcall(selinux_nf_ip_init);
4507 
4508 #ifdef CONFIG_SECURITY_SELINUX_DISABLE
4509 static void selinux_nf_ip_exit(void)
4510 {
4511 	printk(KERN_INFO "SELinux:  Unregistering netfilter hooks\n");
4512 
4513 	nf_unregister_hook(&selinux_ipv4_op);
4514 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
4515 	nf_unregister_hook(&selinux_ipv6_op);
4516 #endif	/* IPV6 */
4517 }
4518 #endif
4519 
4520 #else /* CONFIG_SECURITY_NETWORK && CONFIG_NETFILTER */
4521 
4522 #ifdef CONFIG_SECURITY_SELINUX_DISABLE
4523 #define selinux_nf_ip_exit()
4524 #endif
4525 
4526 #endif /* CONFIG_SECURITY_NETWORK && CONFIG_NETFILTER */
4527 
4528 #ifdef CONFIG_SECURITY_SELINUX_DISABLE
4529 int selinux_disable(void)
4530 {
4531 	extern void exit_sel_fs(void);
4532 	static int selinux_disabled = 0;
4533 
4534 	if (ss_initialized) {
4535 		/* Not permitted after initial policy load. */
4536 		return -EINVAL;
4537 	}
4538 
4539 	if (selinux_disabled) {
4540 		/* Only do this once. */
4541 		return -EINVAL;
4542 	}
4543 
4544 	printk(KERN_INFO "SELinux:  Disabled at runtime.\n");
4545 
4546 	selinux_disabled = 1;
4547 
4548 	/* Reset security_ops to the secondary module, dummy or capability. */
4549 	security_ops = secondary_ops;
4550 
4551 	/* Unregister netfilter hooks. */
4552 	selinux_nf_ip_exit();
4553 
4554 	/* Unregister selinuxfs. */
4555 	exit_sel_fs();
4556 
4557 	return 0;
4558 }
4559 #endif
4560 
4561 
4562