xref: /linux/security/selinux/hooks.c (revision 60b2737de1b1ddfdb90f3ba622634eb49d6f3603)
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 	free_page((unsigned long)nosec_save);
1949 out:
1950 	return rc;
1951 }
1952 
1953 static int selinux_sb_kern_mount(struct super_block *sb, void *data)
1954 {
1955 	struct avc_audit_data ad;
1956 	int rc;
1957 
1958 	rc = superblock_doinit(sb, data);
1959 	if (rc)
1960 		return rc;
1961 
1962 	AVC_AUDIT_DATA_INIT(&ad,FS);
1963 	ad.u.fs.dentry = sb->s_root;
1964 	return superblock_has_perm(current, sb, FILESYSTEM__MOUNT, &ad);
1965 }
1966 
1967 static int selinux_sb_statfs(struct super_block *sb)
1968 {
1969 	struct avc_audit_data ad;
1970 
1971 	AVC_AUDIT_DATA_INIT(&ad,FS);
1972 	ad.u.fs.dentry = sb->s_root;
1973 	return superblock_has_perm(current, sb, FILESYSTEM__GETATTR, &ad);
1974 }
1975 
1976 static int selinux_mount(char * dev_name,
1977                          struct nameidata *nd,
1978                          char * type,
1979                          unsigned long flags,
1980                          void * data)
1981 {
1982 	int rc;
1983 
1984 	rc = secondary_ops->sb_mount(dev_name, nd, type, flags, data);
1985 	if (rc)
1986 		return rc;
1987 
1988 	if (flags & MS_REMOUNT)
1989 		return superblock_has_perm(current, nd->mnt->mnt_sb,
1990 		                           FILESYSTEM__REMOUNT, NULL);
1991 	else
1992 		return dentry_has_perm(current, nd->mnt, nd->dentry,
1993 		                       FILE__MOUNTON);
1994 }
1995 
1996 static int selinux_umount(struct vfsmount *mnt, int flags)
1997 {
1998 	int rc;
1999 
2000 	rc = secondary_ops->sb_umount(mnt, flags);
2001 	if (rc)
2002 		return rc;
2003 
2004 	return superblock_has_perm(current,mnt->mnt_sb,
2005 	                           FILESYSTEM__UNMOUNT,NULL);
2006 }
2007 
2008 /* inode security operations */
2009 
2010 static int selinux_inode_alloc_security(struct inode *inode)
2011 {
2012 	return inode_alloc_security(inode);
2013 }
2014 
2015 static void selinux_inode_free_security(struct inode *inode)
2016 {
2017 	inode_free_security(inode);
2018 }
2019 
2020 static int selinux_inode_create(struct inode *dir, struct dentry *dentry, int mask)
2021 {
2022 	return may_create(dir, dentry, SECCLASS_FILE);
2023 }
2024 
2025 static void selinux_inode_post_create(struct inode *dir, struct dentry *dentry, int mask)
2026 {
2027 	post_create(dir, dentry);
2028 }
2029 
2030 static int selinux_inode_link(struct dentry *old_dentry, struct inode *dir, struct dentry *new_dentry)
2031 {
2032 	int rc;
2033 
2034 	rc = secondary_ops->inode_link(old_dentry,dir,new_dentry);
2035 	if (rc)
2036 		return rc;
2037 	return may_link(dir, old_dentry, MAY_LINK);
2038 }
2039 
2040 static void selinux_inode_post_link(struct dentry *old_dentry, struct inode *inode, struct dentry *new_dentry)
2041 {
2042 	return;
2043 }
2044 
2045 static int selinux_inode_unlink(struct inode *dir, struct dentry *dentry)
2046 {
2047 	int rc;
2048 
2049 	rc = secondary_ops->inode_unlink(dir, dentry);
2050 	if (rc)
2051 		return rc;
2052 	return may_link(dir, dentry, MAY_UNLINK);
2053 }
2054 
2055 static int selinux_inode_symlink(struct inode *dir, struct dentry *dentry, const char *name)
2056 {
2057 	return may_create(dir, dentry, SECCLASS_LNK_FILE);
2058 }
2059 
2060 static void selinux_inode_post_symlink(struct inode *dir, struct dentry *dentry, const char *name)
2061 {
2062 	post_create(dir, dentry);
2063 }
2064 
2065 static int selinux_inode_mkdir(struct inode *dir, struct dentry *dentry, int mask)
2066 {
2067 	return may_create(dir, dentry, SECCLASS_DIR);
2068 }
2069 
2070 static void selinux_inode_post_mkdir(struct inode *dir, struct dentry *dentry, int mask)
2071 {
2072 	post_create(dir, dentry);
2073 }
2074 
2075 static int selinux_inode_rmdir(struct inode *dir, struct dentry *dentry)
2076 {
2077 	return may_link(dir, dentry, MAY_RMDIR);
2078 }
2079 
2080 static int selinux_inode_mknod(struct inode *dir, struct dentry *dentry, int mode, dev_t dev)
2081 {
2082 	int rc;
2083 
2084 	rc = secondary_ops->inode_mknod(dir, dentry, mode, dev);
2085 	if (rc)
2086 		return rc;
2087 
2088 	return may_create(dir, dentry, inode_mode_to_security_class(mode));
2089 }
2090 
2091 static void selinux_inode_post_mknod(struct inode *dir, struct dentry *dentry, int mode, dev_t dev)
2092 {
2093 	post_create(dir, dentry);
2094 }
2095 
2096 static int selinux_inode_rename(struct inode *old_inode, struct dentry *old_dentry,
2097                                 struct inode *new_inode, struct dentry *new_dentry)
2098 {
2099 	return may_rename(old_inode, old_dentry, new_inode, new_dentry);
2100 }
2101 
2102 static void selinux_inode_post_rename(struct inode *old_inode, struct dentry *old_dentry,
2103                                       struct inode *new_inode, struct dentry *new_dentry)
2104 {
2105 	return;
2106 }
2107 
2108 static int selinux_inode_readlink(struct dentry *dentry)
2109 {
2110 	return dentry_has_perm(current, NULL, dentry, FILE__READ);
2111 }
2112 
2113 static int selinux_inode_follow_link(struct dentry *dentry, struct nameidata *nameidata)
2114 {
2115 	int rc;
2116 
2117 	rc = secondary_ops->inode_follow_link(dentry,nameidata);
2118 	if (rc)
2119 		return rc;
2120 	return dentry_has_perm(current, NULL, dentry, FILE__READ);
2121 }
2122 
2123 static int selinux_inode_permission(struct inode *inode, int mask,
2124 				    struct nameidata *nd)
2125 {
2126 	int rc;
2127 
2128 	rc = secondary_ops->inode_permission(inode, mask, nd);
2129 	if (rc)
2130 		return rc;
2131 
2132 	if (!mask) {
2133 		/* No permission to check.  Existence test. */
2134 		return 0;
2135 	}
2136 
2137 	return inode_has_perm(current, inode,
2138 			       file_mask_to_av(inode->i_mode, mask), NULL);
2139 }
2140 
2141 static int selinux_inode_setattr(struct dentry *dentry, struct iattr *iattr)
2142 {
2143 	int rc;
2144 
2145 	rc = secondary_ops->inode_setattr(dentry, iattr);
2146 	if (rc)
2147 		return rc;
2148 
2149 	if (iattr->ia_valid & ATTR_FORCE)
2150 		return 0;
2151 
2152 	if (iattr->ia_valid & (ATTR_MODE | ATTR_UID | ATTR_GID |
2153 			       ATTR_ATIME_SET | ATTR_MTIME_SET))
2154 		return dentry_has_perm(current, NULL, dentry, FILE__SETATTR);
2155 
2156 	return dentry_has_perm(current, NULL, dentry, FILE__WRITE);
2157 }
2158 
2159 static int selinux_inode_getattr(struct vfsmount *mnt, struct dentry *dentry)
2160 {
2161 	return dentry_has_perm(current, mnt, dentry, FILE__GETATTR);
2162 }
2163 
2164 static int selinux_inode_setxattr(struct dentry *dentry, char *name, void *value, size_t size, int flags)
2165 {
2166 	struct task_security_struct *tsec = current->security;
2167 	struct inode *inode = dentry->d_inode;
2168 	struct inode_security_struct *isec = inode->i_security;
2169 	struct superblock_security_struct *sbsec;
2170 	struct avc_audit_data ad;
2171 	u32 newsid;
2172 	int rc = 0;
2173 
2174 	if (strcmp(name, XATTR_NAME_SELINUX)) {
2175 		if (!strncmp(name, XATTR_SECURITY_PREFIX,
2176 			     sizeof XATTR_SECURITY_PREFIX - 1) &&
2177 		    !capable(CAP_SYS_ADMIN)) {
2178 			/* A different attribute in the security namespace.
2179 			   Restrict to administrator. */
2180 			return -EPERM;
2181 		}
2182 
2183 		/* Not an attribute we recognize, so just check the
2184 		   ordinary setattr permission. */
2185 		return dentry_has_perm(current, NULL, dentry, FILE__SETATTR);
2186 	}
2187 
2188 	sbsec = inode->i_sb->s_security;
2189 	if (sbsec->behavior == SECURITY_FS_USE_MNTPOINT)
2190 		return -EOPNOTSUPP;
2191 
2192 	if ((current->fsuid != inode->i_uid) && !capable(CAP_FOWNER))
2193 		return -EPERM;
2194 
2195 	AVC_AUDIT_DATA_INIT(&ad,FS);
2196 	ad.u.fs.dentry = dentry;
2197 
2198 	rc = avc_has_perm(tsec->sid, isec->sid, isec->sclass,
2199 			  FILE__RELABELFROM, &ad);
2200 	if (rc)
2201 		return rc;
2202 
2203 	rc = security_context_to_sid(value, size, &newsid);
2204 	if (rc)
2205 		return rc;
2206 
2207 	rc = avc_has_perm(tsec->sid, newsid, isec->sclass,
2208 			  FILE__RELABELTO, &ad);
2209 	if (rc)
2210 		return rc;
2211 
2212 	rc = security_validate_transition(isec->sid, newsid, tsec->sid,
2213 	                                  isec->sclass);
2214 	if (rc)
2215 		return rc;
2216 
2217 	return avc_has_perm(newsid,
2218 			    sbsec->sid,
2219 			    SECCLASS_FILESYSTEM,
2220 			    FILESYSTEM__ASSOCIATE,
2221 			    &ad);
2222 }
2223 
2224 static void selinux_inode_post_setxattr(struct dentry *dentry, char *name,
2225                                         void *value, size_t size, int flags)
2226 {
2227 	struct inode *inode = dentry->d_inode;
2228 	struct inode_security_struct *isec = inode->i_security;
2229 	u32 newsid;
2230 	int rc;
2231 
2232 	if (strcmp(name, XATTR_NAME_SELINUX)) {
2233 		/* Not an attribute we recognize, so nothing to do. */
2234 		return;
2235 	}
2236 
2237 	rc = security_context_to_sid(value, size, &newsid);
2238 	if (rc) {
2239 		printk(KERN_WARNING "%s:  unable to obtain SID for context "
2240 		       "%s, rc=%d\n", __FUNCTION__, (char*)value, -rc);
2241 		return;
2242 	}
2243 
2244 	isec->sid = newsid;
2245 	return;
2246 }
2247 
2248 static int selinux_inode_getxattr (struct dentry *dentry, char *name)
2249 {
2250 	struct inode *inode = dentry->d_inode;
2251 	struct superblock_security_struct *sbsec = inode->i_sb->s_security;
2252 
2253 	if (sbsec->behavior == SECURITY_FS_USE_MNTPOINT)
2254 		return -EOPNOTSUPP;
2255 
2256 	return dentry_has_perm(current, NULL, dentry, FILE__GETATTR);
2257 }
2258 
2259 static int selinux_inode_listxattr (struct dentry *dentry)
2260 {
2261 	return dentry_has_perm(current, NULL, dentry, FILE__GETATTR);
2262 }
2263 
2264 static int selinux_inode_removexattr (struct dentry *dentry, char *name)
2265 {
2266 	if (strcmp(name, XATTR_NAME_SELINUX)) {
2267 		if (!strncmp(name, XATTR_SECURITY_PREFIX,
2268 			     sizeof XATTR_SECURITY_PREFIX - 1) &&
2269 		    !capable(CAP_SYS_ADMIN)) {
2270 			/* A different attribute in the security namespace.
2271 			   Restrict to administrator. */
2272 			return -EPERM;
2273 		}
2274 
2275 		/* Not an attribute we recognize, so just check the
2276 		   ordinary setattr permission. Might want a separate
2277 		   permission for removexattr. */
2278 		return dentry_has_perm(current, NULL, dentry, FILE__SETATTR);
2279 	}
2280 
2281 	/* No one is allowed to remove a SELinux security label.
2282 	   You can change the label, but all data must be labeled. */
2283 	return -EACCES;
2284 }
2285 
2286 static int selinux_inode_getsecurity(struct inode *inode, const char *name, void *buffer, size_t size)
2287 {
2288 	struct inode_security_struct *isec = inode->i_security;
2289 	char *context;
2290 	unsigned len;
2291 	int rc;
2292 
2293 	/* Permission check handled by selinux_inode_getxattr hook.*/
2294 
2295 	if (strcmp(name, XATTR_SELINUX_SUFFIX))
2296 		return -EOPNOTSUPP;
2297 
2298 	rc = security_sid_to_context(isec->sid, &context, &len);
2299 	if (rc)
2300 		return rc;
2301 
2302 	if (!buffer || !size) {
2303 		kfree(context);
2304 		return len;
2305 	}
2306 	if (size < len) {
2307 		kfree(context);
2308 		return -ERANGE;
2309 	}
2310 	memcpy(buffer, context, len);
2311 	kfree(context);
2312 	return len;
2313 }
2314 
2315 static int selinux_inode_setsecurity(struct inode *inode, const char *name,
2316                                      const void *value, size_t size, int flags)
2317 {
2318 	struct inode_security_struct *isec = inode->i_security;
2319 	u32 newsid;
2320 	int rc;
2321 
2322 	if (strcmp(name, XATTR_SELINUX_SUFFIX))
2323 		return -EOPNOTSUPP;
2324 
2325 	if (!value || !size)
2326 		return -EACCES;
2327 
2328 	rc = security_context_to_sid((void*)value, size, &newsid);
2329 	if (rc)
2330 		return rc;
2331 
2332 	isec->sid = newsid;
2333 	return 0;
2334 }
2335 
2336 static int selinux_inode_listsecurity(struct inode *inode, char *buffer, size_t buffer_size)
2337 {
2338 	const int len = sizeof(XATTR_NAME_SELINUX);
2339 	if (buffer && len <= buffer_size)
2340 		memcpy(buffer, XATTR_NAME_SELINUX, len);
2341 	return len;
2342 }
2343 
2344 /* file security operations */
2345 
2346 static int selinux_file_permission(struct file *file, int mask)
2347 {
2348 	struct inode *inode = file->f_dentry->d_inode;
2349 
2350 	if (!mask) {
2351 		/* No permission to check.  Existence test. */
2352 		return 0;
2353 	}
2354 
2355 	/* file_mask_to_av won't add FILE__WRITE if MAY_APPEND is set */
2356 	if ((file->f_flags & O_APPEND) && (mask & MAY_WRITE))
2357 		mask |= MAY_APPEND;
2358 
2359 	return file_has_perm(current, file,
2360 			     file_mask_to_av(inode->i_mode, mask));
2361 }
2362 
2363 static int selinux_file_alloc_security(struct file *file)
2364 {
2365 	return file_alloc_security(file);
2366 }
2367 
2368 static void selinux_file_free_security(struct file *file)
2369 {
2370 	file_free_security(file);
2371 }
2372 
2373 static int selinux_file_ioctl(struct file *file, unsigned int cmd,
2374 			      unsigned long arg)
2375 {
2376 	int error = 0;
2377 
2378 	switch (cmd) {
2379 		case FIONREAD:
2380 		/* fall through */
2381 		case FIBMAP:
2382 		/* fall through */
2383 		case FIGETBSZ:
2384 		/* fall through */
2385 		case EXT2_IOC_GETFLAGS:
2386 		/* fall through */
2387 		case EXT2_IOC_GETVERSION:
2388 			error = file_has_perm(current, file, FILE__GETATTR);
2389 			break;
2390 
2391 		case EXT2_IOC_SETFLAGS:
2392 		/* fall through */
2393 		case EXT2_IOC_SETVERSION:
2394 			error = file_has_perm(current, file, FILE__SETATTR);
2395 			break;
2396 
2397 		/* sys_ioctl() checks */
2398 		case FIONBIO:
2399 		/* fall through */
2400 		case FIOASYNC:
2401 			error = file_has_perm(current, file, 0);
2402 			break;
2403 
2404 	        case KDSKBENT:
2405 	        case KDSKBSENT:
2406 			error = task_has_capability(current,CAP_SYS_TTY_CONFIG);
2407 			break;
2408 
2409 		/* default case assumes that the command will go
2410 		 * to the file's ioctl() function.
2411 		 */
2412 		default:
2413 			error = file_has_perm(current, file, FILE__IOCTL);
2414 
2415 	}
2416 	return error;
2417 }
2418 
2419 static int file_map_prot_check(struct file *file, unsigned long prot, int shared)
2420 {
2421 #ifndef CONFIG_PPC32
2422 	if ((prot & PROT_EXEC) && (!file || (!shared && (prot & PROT_WRITE)))) {
2423 		/*
2424 		 * We are making executable an anonymous mapping or a
2425 		 * private file mapping that will also be writable.
2426 		 * This has an additional check.
2427 		 */
2428 		int rc = task_has_perm(current, current, PROCESS__EXECMEM);
2429 		if (rc)
2430 			return rc;
2431 	}
2432 #endif
2433 
2434 	if (file) {
2435 		/* read access is always possible with a mapping */
2436 		u32 av = FILE__READ;
2437 
2438 		/* write access only matters if the mapping is shared */
2439 		if (shared && (prot & PROT_WRITE))
2440 			av |= FILE__WRITE;
2441 
2442 		if (prot & PROT_EXEC)
2443 			av |= FILE__EXECUTE;
2444 
2445 		return file_has_perm(current, file, av);
2446 	}
2447 	return 0;
2448 }
2449 
2450 static int selinux_file_mmap(struct file *file, unsigned long reqprot,
2451 			     unsigned long prot, unsigned long flags)
2452 {
2453 	int rc;
2454 
2455 	rc = secondary_ops->file_mmap(file, reqprot, prot, flags);
2456 	if (rc)
2457 		return rc;
2458 
2459 	if (selinux_checkreqprot)
2460 		prot = reqprot;
2461 
2462 	return file_map_prot_check(file, prot,
2463 				   (flags & MAP_TYPE) == MAP_SHARED);
2464 }
2465 
2466 static int selinux_file_mprotect(struct vm_area_struct *vma,
2467 				 unsigned long reqprot,
2468 				 unsigned long prot)
2469 {
2470 	int rc;
2471 
2472 	rc = secondary_ops->file_mprotect(vma, reqprot, prot);
2473 	if (rc)
2474 		return rc;
2475 
2476 	if (selinux_checkreqprot)
2477 		prot = reqprot;
2478 
2479 #ifndef CONFIG_PPC32
2480 	if (vma->vm_file != NULL && vma->anon_vma != NULL && (prot & PROT_EXEC)) {
2481 		/*
2482 		 * We are making executable a file mapping that has
2483 		 * had some COW done. Since pages might have been written,
2484 		 * check ability to execute the possibly modified content.
2485 		 * This typically should only occur for text relocations.
2486 		 */
2487 		int rc = file_has_perm(current, vma->vm_file, FILE__EXECMOD);
2488 		if (rc)
2489 			return rc;
2490 	}
2491 #endif
2492 
2493 	return file_map_prot_check(vma->vm_file, prot, vma->vm_flags&VM_SHARED);
2494 }
2495 
2496 static int selinux_file_lock(struct file *file, unsigned int cmd)
2497 {
2498 	return file_has_perm(current, file, FILE__LOCK);
2499 }
2500 
2501 static int selinux_file_fcntl(struct file *file, unsigned int cmd,
2502 			      unsigned long arg)
2503 {
2504 	int err = 0;
2505 
2506 	switch (cmd) {
2507 	        case F_SETFL:
2508 			if (!file->f_dentry || !file->f_dentry->d_inode) {
2509 				err = -EINVAL;
2510 				break;
2511 			}
2512 
2513 			if ((file->f_flags & O_APPEND) && !(arg & O_APPEND)) {
2514 				err = file_has_perm(current, file,FILE__WRITE);
2515 				break;
2516 			}
2517 			/* fall through */
2518 	        case F_SETOWN:
2519 	        case F_SETSIG:
2520 	        case F_GETFL:
2521 	        case F_GETOWN:
2522 	        case F_GETSIG:
2523 			/* Just check FD__USE permission */
2524 			err = file_has_perm(current, file, 0);
2525 			break;
2526 		case F_GETLK:
2527 		case F_SETLK:
2528 	        case F_SETLKW:
2529 #if BITS_PER_LONG == 32
2530 	        case F_GETLK64:
2531 		case F_SETLK64:
2532 	        case F_SETLKW64:
2533 #endif
2534 			if (!file->f_dentry || !file->f_dentry->d_inode) {
2535 				err = -EINVAL;
2536 				break;
2537 			}
2538 			err = file_has_perm(current, file, FILE__LOCK);
2539 			break;
2540 	}
2541 
2542 	return err;
2543 }
2544 
2545 static int selinux_file_set_fowner(struct file *file)
2546 {
2547 	struct task_security_struct *tsec;
2548 	struct file_security_struct *fsec;
2549 
2550 	tsec = current->security;
2551 	fsec = file->f_security;
2552 	fsec->fown_sid = tsec->sid;
2553 
2554 	return 0;
2555 }
2556 
2557 static int selinux_file_send_sigiotask(struct task_struct *tsk,
2558 				       struct fown_struct *fown, int signum)
2559 {
2560         struct file *file;
2561 	u32 perm;
2562 	struct task_security_struct *tsec;
2563 	struct file_security_struct *fsec;
2564 
2565 	/* struct fown_struct is never outside the context of a struct file */
2566         file = (struct file *)((long)fown - offsetof(struct file,f_owner));
2567 
2568 	tsec = tsk->security;
2569 	fsec = file->f_security;
2570 
2571 	if (!signum)
2572 		perm = signal_to_av(SIGIO); /* as per send_sigio_to_task */
2573 	else
2574 		perm = signal_to_av(signum);
2575 
2576 	return avc_has_perm(fsec->fown_sid, tsec->sid,
2577 			    SECCLASS_PROCESS, perm, NULL);
2578 }
2579 
2580 static int selinux_file_receive(struct file *file)
2581 {
2582 	return file_has_perm(current, file, file_to_av(file));
2583 }
2584 
2585 /* task security operations */
2586 
2587 static int selinux_task_create(unsigned long clone_flags)
2588 {
2589 	int rc;
2590 
2591 	rc = secondary_ops->task_create(clone_flags);
2592 	if (rc)
2593 		return rc;
2594 
2595 	return task_has_perm(current, current, PROCESS__FORK);
2596 }
2597 
2598 static int selinux_task_alloc_security(struct task_struct *tsk)
2599 {
2600 	struct task_security_struct *tsec1, *tsec2;
2601 	int rc;
2602 
2603 	tsec1 = current->security;
2604 
2605 	rc = task_alloc_security(tsk);
2606 	if (rc)
2607 		return rc;
2608 	tsec2 = tsk->security;
2609 
2610 	tsec2->osid = tsec1->osid;
2611 	tsec2->sid = tsec1->sid;
2612 
2613 	/* Retain the exec and create SIDs across fork */
2614 	tsec2->exec_sid = tsec1->exec_sid;
2615 	tsec2->create_sid = tsec1->create_sid;
2616 
2617 	/* Retain ptracer SID across fork, if any.
2618 	   This will be reset by the ptrace hook upon any
2619 	   subsequent ptrace_attach operations. */
2620 	tsec2->ptrace_sid = tsec1->ptrace_sid;
2621 
2622 	return 0;
2623 }
2624 
2625 static void selinux_task_free_security(struct task_struct *tsk)
2626 {
2627 	task_free_security(tsk);
2628 }
2629 
2630 static int selinux_task_setuid(uid_t id0, uid_t id1, uid_t id2, int flags)
2631 {
2632 	/* Since setuid only affects the current process, and
2633 	   since the SELinux controls are not based on the Linux
2634 	   identity attributes, SELinux does not need to control
2635 	   this operation.  However, SELinux does control the use
2636 	   of the CAP_SETUID and CAP_SETGID capabilities using the
2637 	   capable hook. */
2638 	return 0;
2639 }
2640 
2641 static int selinux_task_post_setuid(uid_t id0, uid_t id1, uid_t id2, int flags)
2642 {
2643 	return secondary_ops->task_post_setuid(id0,id1,id2,flags);
2644 }
2645 
2646 static int selinux_task_setgid(gid_t id0, gid_t id1, gid_t id2, int flags)
2647 {
2648 	/* See the comment for setuid above. */
2649 	return 0;
2650 }
2651 
2652 static int selinux_task_setpgid(struct task_struct *p, pid_t pgid)
2653 {
2654 	return task_has_perm(current, p, PROCESS__SETPGID);
2655 }
2656 
2657 static int selinux_task_getpgid(struct task_struct *p)
2658 {
2659 	return task_has_perm(current, p, PROCESS__GETPGID);
2660 }
2661 
2662 static int selinux_task_getsid(struct task_struct *p)
2663 {
2664 	return task_has_perm(current, p, PROCESS__GETSESSION);
2665 }
2666 
2667 static int selinux_task_setgroups(struct group_info *group_info)
2668 {
2669 	/* See the comment for setuid above. */
2670 	return 0;
2671 }
2672 
2673 static int selinux_task_setnice(struct task_struct *p, int nice)
2674 {
2675 	int rc;
2676 
2677 	rc = secondary_ops->task_setnice(p, nice);
2678 	if (rc)
2679 		return rc;
2680 
2681 	return task_has_perm(current,p, PROCESS__SETSCHED);
2682 }
2683 
2684 static int selinux_task_setrlimit(unsigned int resource, struct rlimit *new_rlim)
2685 {
2686 	struct rlimit *old_rlim = current->signal->rlim + resource;
2687 	int rc;
2688 
2689 	rc = secondary_ops->task_setrlimit(resource, new_rlim);
2690 	if (rc)
2691 		return rc;
2692 
2693 	/* Control the ability to change the hard limit (whether
2694 	   lowering or raising it), so that the hard limit can
2695 	   later be used as a safe reset point for the soft limit
2696 	   upon context transitions. See selinux_bprm_apply_creds. */
2697 	if (old_rlim->rlim_max != new_rlim->rlim_max)
2698 		return task_has_perm(current, current, PROCESS__SETRLIMIT);
2699 
2700 	return 0;
2701 }
2702 
2703 static int selinux_task_setscheduler(struct task_struct *p, int policy, struct sched_param *lp)
2704 {
2705 	return task_has_perm(current, p, PROCESS__SETSCHED);
2706 }
2707 
2708 static int selinux_task_getscheduler(struct task_struct *p)
2709 {
2710 	return task_has_perm(current, p, PROCESS__GETSCHED);
2711 }
2712 
2713 static int selinux_task_kill(struct task_struct *p, struct siginfo *info, int sig)
2714 {
2715 	u32 perm;
2716 	int rc;
2717 
2718 	rc = secondary_ops->task_kill(p, info, sig);
2719 	if (rc)
2720 		return rc;
2721 
2722 	if (info && ((unsigned long)info == 1 ||
2723 	             (unsigned long)info == 2 || SI_FROMKERNEL(info)))
2724 		return 0;
2725 
2726 	if (!sig)
2727 		perm = PROCESS__SIGNULL; /* null signal; existence test */
2728 	else
2729 		perm = signal_to_av(sig);
2730 
2731 	return task_has_perm(current, p, perm);
2732 }
2733 
2734 static int selinux_task_prctl(int option,
2735 			      unsigned long arg2,
2736 			      unsigned long arg3,
2737 			      unsigned long arg4,
2738 			      unsigned long arg5)
2739 {
2740 	/* The current prctl operations do not appear to require
2741 	   any SELinux controls since they merely observe or modify
2742 	   the state of the current process. */
2743 	return 0;
2744 }
2745 
2746 static int selinux_task_wait(struct task_struct *p)
2747 {
2748 	u32 perm;
2749 
2750 	perm = signal_to_av(p->exit_signal);
2751 
2752 	return task_has_perm(p, current, perm);
2753 }
2754 
2755 static void selinux_task_reparent_to_init(struct task_struct *p)
2756 {
2757   	struct task_security_struct *tsec;
2758 
2759 	secondary_ops->task_reparent_to_init(p);
2760 
2761 	tsec = p->security;
2762 	tsec->osid = tsec->sid;
2763 	tsec->sid = SECINITSID_KERNEL;
2764 	return;
2765 }
2766 
2767 static void selinux_task_to_inode(struct task_struct *p,
2768 				  struct inode *inode)
2769 {
2770 	struct task_security_struct *tsec = p->security;
2771 	struct inode_security_struct *isec = inode->i_security;
2772 
2773 	isec->sid = tsec->sid;
2774 	isec->initialized = 1;
2775 	return;
2776 }
2777 
2778 #ifdef CONFIG_SECURITY_NETWORK
2779 
2780 /* Returns error only if unable to parse addresses */
2781 static int selinux_parse_skb_ipv4(struct sk_buff *skb, struct avc_audit_data *ad)
2782 {
2783 	int offset, ihlen, ret = -EINVAL;
2784 	struct iphdr _iph, *ih;
2785 
2786 	offset = skb->nh.raw - skb->data;
2787 	ih = skb_header_pointer(skb, offset, sizeof(_iph), &_iph);
2788 	if (ih == NULL)
2789 		goto out;
2790 
2791 	ihlen = ih->ihl * 4;
2792 	if (ihlen < sizeof(_iph))
2793 		goto out;
2794 
2795 	ad->u.net.v4info.saddr = ih->saddr;
2796 	ad->u.net.v4info.daddr = ih->daddr;
2797 	ret = 0;
2798 
2799 	switch (ih->protocol) {
2800         case IPPROTO_TCP: {
2801         	struct tcphdr _tcph, *th;
2802 
2803         	if (ntohs(ih->frag_off) & IP_OFFSET)
2804         		break;
2805 
2806 		offset += ihlen;
2807 		th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph);
2808 		if (th == NULL)
2809 			break;
2810 
2811 		ad->u.net.sport = th->source;
2812 		ad->u.net.dport = th->dest;
2813 		break;
2814         }
2815 
2816         case IPPROTO_UDP: {
2817         	struct udphdr _udph, *uh;
2818 
2819         	if (ntohs(ih->frag_off) & IP_OFFSET)
2820         		break;
2821 
2822 		offset += ihlen;
2823         	uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph);
2824 		if (uh == NULL)
2825 			break;
2826 
2827         	ad->u.net.sport = uh->source;
2828         	ad->u.net.dport = uh->dest;
2829         	break;
2830         }
2831 
2832         default:
2833         	break;
2834         }
2835 out:
2836 	return ret;
2837 }
2838 
2839 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
2840 
2841 /* Returns error only if unable to parse addresses */
2842 static int selinux_parse_skb_ipv6(struct sk_buff *skb, struct avc_audit_data *ad)
2843 {
2844 	u8 nexthdr;
2845 	int ret = -EINVAL, offset;
2846 	struct ipv6hdr _ipv6h, *ip6;
2847 
2848 	offset = skb->nh.raw - skb->data;
2849 	ip6 = skb_header_pointer(skb, offset, sizeof(_ipv6h), &_ipv6h);
2850 	if (ip6 == NULL)
2851 		goto out;
2852 
2853 	ipv6_addr_copy(&ad->u.net.v6info.saddr, &ip6->saddr);
2854 	ipv6_addr_copy(&ad->u.net.v6info.daddr, &ip6->daddr);
2855 	ret = 0;
2856 
2857 	nexthdr = ip6->nexthdr;
2858 	offset += sizeof(_ipv6h);
2859 	offset = ipv6_skip_exthdr(skb, offset, &nexthdr);
2860 	if (offset < 0)
2861 		goto out;
2862 
2863 	switch (nexthdr) {
2864 	case IPPROTO_TCP: {
2865         	struct tcphdr _tcph, *th;
2866 
2867 		th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph);
2868 		if (th == NULL)
2869 			break;
2870 
2871 		ad->u.net.sport = th->source;
2872 		ad->u.net.dport = th->dest;
2873 		break;
2874 	}
2875 
2876 	case IPPROTO_UDP: {
2877 		struct udphdr _udph, *uh;
2878 
2879 		uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph);
2880 		if (uh == NULL)
2881 			break;
2882 
2883 		ad->u.net.sport = uh->source;
2884 		ad->u.net.dport = uh->dest;
2885 		break;
2886 	}
2887 
2888 	/* includes fragments */
2889 	default:
2890 		break;
2891 	}
2892 out:
2893 	return ret;
2894 }
2895 
2896 #endif /* IPV6 */
2897 
2898 static int selinux_parse_skb(struct sk_buff *skb, struct avc_audit_data *ad,
2899 			     char **addrp, int *len, int src)
2900 {
2901 	int ret = 0;
2902 
2903 	switch (ad->u.net.family) {
2904 	case PF_INET:
2905 		ret = selinux_parse_skb_ipv4(skb, ad);
2906 		if (ret || !addrp)
2907 			break;
2908 		*len = 4;
2909 		*addrp = (char *)(src ? &ad->u.net.v4info.saddr :
2910 					&ad->u.net.v4info.daddr);
2911 		break;
2912 
2913 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
2914 	case PF_INET6:
2915 		ret = selinux_parse_skb_ipv6(skb, ad);
2916 		if (ret || !addrp)
2917 			break;
2918 		*len = 16;
2919 		*addrp = (char *)(src ? &ad->u.net.v6info.saddr :
2920 					&ad->u.net.v6info.daddr);
2921 		break;
2922 #endif	/* IPV6 */
2923 	default:
2924 		break;
2925 	}
2926 
2927 	return ret;
2928 }
2929 
2930 /* socket security operations */
2931 static int socket_has_perm(struct task_struct *task, struct socket *sock,
2932 			   u32 perms)
2933 {
2934 	struct inode_security_struct *isec;
2935 	struct task_security_struct *tsec;
2936 	struct avc_audit_data ad;
2937 	int err = 0;
2938 
2939 	tsec = task->security;
2940 	isec = SOCK_INODE(sock)->i_security;
2941 
2942 	if (isec->sid == SECINITSID_KERNEL)
2943 		goto out;
2944 
2945 	AVC_AUDIT_DATA_INIT(&ad,NET);
2946 	ad.u.net.sk = sock->sk;
2947 	err = avc_has_perm(tsec->sid, isec->sid, isec->sclass, perms, &ad);
2948 
2949 out:
2950 	return err;
2951 }
2952 
2953 static int selinux_socket_create(int family, int type,
2954 				 int protocol, int kern)
2955 {
2956 	int err = 0;
2957 	struct task_security_struct *tsec;
2958 
2959 	if (kern)
2960 		goto out;
2961 
2962 	tsec = current->security;
2963 	err = avc_has_perm(tsec->sid, tsec->sid,
2964 			   socket_type_to_security_class(family, type,
2965 			   protocol), SOCKET__CREATE, NULL);
2966 
2967 out:
2968 	return err;
2969 }
2970 
2971 static void selinux_socket_post_create(struct socket *sock, int family,
2972 				       int type, int protocol, int kern)
2973 {
2974 	struct inode_security_struct *isec;
2975 	struct task_security_struct *tsec;
2976 
2977 	isec = SOCK_INODE(sock)->i_security;
2978 
2979 	tsec = current->security;
2980 	isec->sclass = socket_type_to_security_class(family, type, protocol);
2981 	isec->sid = kern ? SECINITSID_KERNEL : tsec->sid;
2982 	isec->initialized = 1;
2983 
2984 	return;
2985 }
2986 
2987 /* Range of port numbers used to automatically bind.
2988    Need to determine whether we should perform a name_bind
2989    permission check between the socket and the port number. */
2990 #define ip_local_port_range_0 sysctl_local_port_range[0]
2991 #define ip_local_port_range_1 sysctl_local_port_range[1]
2992 
2993 static int selinux_socket_bind(struct socket *sock, struct sockaddr *address, int addrlen)
2994 {
2995 	u16 family;
2996 	int err;
2997 
2998 	err = socket_has_perm(current, sock, SOCKET__BIND);
2999 	if (err)
3000 		goto out;
3001 
3002 	/*
3003 	 * If PF_INET or PF_INET6, check name_bind permission for the port.
3004 	 */
3005 	family = sock->sk->sk_family;
3006 	if (family == PF_INET || family == PF_INET6) {
3007 		char *addrp;
3008 		struct inode_security_struct *isec;
3009 		struct task_security_struct *tsec;
3010 		struct avc_audit_data ad;
3011 		struct sockaddr_in *addr4 = NULL;
3012 		struct sockaddr_in6 *addr6 = NULL;
3013 		unsigned short snum;
3014 		struct sock *sk = sock->sk;
3015 		u32 sid, node_perm, addrlen;
3016 
3017 		tsec = current->security;
3018 		isec = SOCK_INODE(sock)->i_security;
3019 
3020 		if (family == PF_INET) {
3021 			addr4 = (struct sockaddr_in *)address;
3022 			snum = ntohs(addr4->sin_port);
3023 			addrlen = sizeof(addr4->sin_addr.s_addr);
3024 			addrp = (char *)&addr4->sin_addr.s_addr;
3025 		} else {
3026 			addr6 = (struct sockaddr_in6 *)address;
3027 			snum = ntohs(addr6->sin6_port);
3028 			addrlen = sizeof(addr6->sin6_addr.s6_addr);
3029 			addrp = (char *)&addr6->sin6_addr.s6_addr;
3030 		}
3031 
3032 		if (snum&&(snum < max(PROT_SOCK,ip_local_port_range_0) ||
3033 			   snum > ip_local_port_range_1)) {
3034 			err = security_port_sid(sk->sk_family, sk->sk_type,
3035 						sk->sk_protocol, snum, &sid);
3036 			if (err)
3037 				goto out;
3038 			AVC_AUDIT_DATA_INIT(&ad,NET);
3039 			ad.u.net.sport = htons(snum);
3040 			ad.u.net.family = family;
3041 			err = avc_has_perm(isec->sid, sid,
3042 					   isec->sclass,
3043 					   SOCKET__NAME_BIND, &ad);
3044 			if (err)
3045 				goto out;
3046 		}
3047 
3048 		switch(sk->sk_protocol) {
3049 		case IPPROTO_TCP:
3050 			node_perm = TCP_SOCKET__NODE_BIND;
3051 			break;
3052 
3053 		case IPPROTO_UDP:
3054 			node_perm = UDP_SOCKET__NODE_BIND;
3055 			break;
3056 
3057 		default:
3058 			node_perm = RAWIP_SOCKET__NODE_BIND;
3059 			break;
3060 		}
3061 
3062 		err = security_node_sid(family, addrp, addrlen, &sid);
3063 		if (err)
3064 			goto out;
3065 
3066 		AVC_AUDIT_DATA_INIT(&ad,NET);
3067 		ad.u.net.sport = htons(snum);
3068 		ad.u.net.family = family;
3069 
3070 		if (family == PF_INET)
3071 			ad.u.net.v4info.saddr = addr4->sin_addr.s_addr;
3072 		else
3073 			ipv6_addr_copy(&ad.u.net.v6info.saddr, &addr6->sin6_addr);
3074 
3075 		err = avc_has_perm(isec->sid, sid,
3076 		                   isec->sclass, node_perm, &ad);
3077 		if (err)
3078 			goto out;
3079 	}
3080 out:
3081 	return err;
3082 }
3083 
3084 static int selinux_socket_connect(struct socket *sock, struct sockaddr *address, int addrlen)
3085 {
3086 	struct inode_security_struct *isec;
3087 	int err;
3088 
3089 	err = socket_has_perm(current, sock, SOCKET__CONNECT);
3090 	if (err)
3091 		return err;
3092 
3093 	/*
3094 	 * If a TCP socket, check name_connect permission for the port.
3095 	 */
3096 	isec = SOCK_INODE(sock)->i_security;
3097 	if (isec->sclass == SECCLASS_TCP_SOCKET) {
3098 		struct sock *sk = sock->sk;
3099 		struct avc_audit_data ad;
3100 		struct sockaddr_in *addr4 = NULL;
3101 		struct sockaddr_in6 *addr6 = NULL;
3102 		unsigned short snum;
3103 		u32 sid;
3104 
3105 		if (sk->sk_family == PF_INET) {
3106 			addr4 = (struct sockaddr_in *)address;
3107 			if (addrlen != sizeof(struct sockaddr_in))
3108 				return -EINVAL;
3109 			snum = ntohs(addr4->sin_port);
3110 		} else {
3111 			addr6 = (struct sockaddr_in6 *)address;
3112 			if (addrlen != sizeof(struct sockaddr_in6))
3113 				return -EINVAL;
3114 			snum = ntohs(addr6->sin6_port);
3115 		}
3116 
3117 		err = security_port_sid(sk->sk_family, sk->sk_type,
3118 					sk->sk_protocol, snum, &sid);
3119 		if (err)
3120 			goto out;
3121 
3122 		AVC_AUDIT_DATA_INIT(&ad,NET);
3123 		ad.u.net.dport = htons(snum);
3124 		ad.u.net.family = sk->sk_family;
3125 		err = avc_has_perm(isec->sid, sid, isec->sclass,
3126 				   TCP_SOCKET__NAME_CONNECT, &ad);
3127 		if (err)
3128 			goto out;
3129 	}
3130 
3131 out:
3132 	return err;
3133 }
3134 
3135 static int selinux_socket_listen(struct socket *sock, int backlog)
3136 {
3137 	return socket_has_perm(current, sock, SOCKET__LISTEN);
3138 }
3139 
3140 static int selinux_socket_accept(struct socket *sock, struct socket *newsock)
3141 {
3142 	int err;
3143 	struct inode_security_struct *isec;
3144 	struct inode_security_struct *newisec;
3145 
3146 	err = socket_has_perm(current, sock, SOCKET__ACCEPT);
3147 	if (err)
3148 		return err;
3149 
3150 	newisec = SOCK_INODE(newsock)->i_security;
3151 
3152 	isec = SOCK_INODE(sock)->i_security;
3153 	newisec->sclass = isec->sclass;
3154 	newisec->sid = isec->sid;
3155 	newisec->initialized = 1;
3156 
3157 	return 0;
3158 }
3159 
3160 static int selinux_socket_sendmsg(struct socket *sock, struct msghdr *msg,
3161  				  int size)
3162 {
3163 	return socket_has_perm(current, sock, SOCKET__WRITE);
3164 }
3165 
3166 static int selinux_socket_recvmsg(struct socket *sock, struct msghdr *msg,
3167 				  int size, int flags)
3168 {
3169 	return socket_has_perm(current, sock, SOCKET__READ);
3170 }
3171 
3172 static int selinux_socket_getsockname(struct socket *sock)
3173 {
3174 	return socket_has_perm(current, sock, SOCKET__GETATTR);
3175 }
3176 
3177 static int selinux_socket_getpeername(struct socket *sock)
3178 {
3179 	return socket_has_perm(current, sock, SOCKET__GETATTR);
3180 }
3181 
3182 static int selinux_socket_setsockopt(struct socket *sock,int level,int optname)
3183 {
3184 	return socket_has_perm(current, sock, SOCKET__SETOPT);
3185 }
3186 
3187 static int selinux_socket_getsockopt(struct socket *sock, int level,
3188 				     int optname)
3189 {
3190 	return socket_has_perm(current, sock, SOCKET__GETOPT);
3191 }
3192 
3193 static int selinux_socket_shutdown(struct socket *sock, int how)
3194 {
3195 	return socket_has_perm(current, sock, SOCKET__SHUTDOWN);
3196 }
3197 
3198 static int selinux_socket_unix_stream_connect(struct socket *sock,
3199 					      struct socket *other,
3200 					      struct sock *newsk)
3201 {
3202 	struct sk_security_struct *ssec;
3203 	struct inode_security_struct *isec;
3204 	struct inode_security_struct *other_isec;
3205 	struct avc_audit_data ad;
3206 	int err;
3207 
3208 	err = secondary_ops->unix_stream_connect(sock, other, newsk);
3209 	if (err)
3210 		return err;
3211 
3212 	isec = SOCK_INODE(sock)->i_security;
3213 	other_isec = SOCK_INODE(other)->i_security;
3214 
3215 	AVC_AUDIT_DATA_INIT(&ad,NET);
3216 	ad.u.net.sk = other->sk;
3217 
3218 	err = avc_has_perm(isec->sid, other_isec->sid,
3219 			   isec->sclass,
3220 			   UNIX_STREAM_SOCKET__CONNECTTO, &ad);
3221 	if (err)
3222 		return err;
3223 
3224 	/* connecting socket */
3225 	ssec = sock->sk->sk_security;
3226 	ssec->peer_sid = other_isec->sid;
3227 
3228 	/* server child socket */
3229 	ssec = newsk->sk_security;
3230 	ssec->peer_sid = isec->sid;
3231 
3232 	return 0;
3233 }
3234 
3235 static int selinux_socket_unix_may_send(struct socket *sock,
3236 					struct socket *other)
3237 {
3238 	struct inode_security_struct *isec;
3239 	struct inode_security_struct *other_isec;
3240 	struct avc_audit_data ad;
3241 	int err;
3242 
3243 	isec = SOCK_INODE(sock)->i_security;
3244 	other_isec = SOCK_INODE(other)->i_security;
3245 
3246 	AVC_AUDIT_DATA_INIT(&ad,NET);
3247 	ad.u.net.sk = other->sk;
3248 
3249 	err = avc_has_perm(isec->sid, other_isec->sid,
3250 			   isec->sclass, SOCKET__SENDTO, &ad);
3251 	if (err)
3252 		return err;
3253 
3254 	return 0;
3255 }
3256 
3257 static int selinux_socket_sock_rcv_skb(struct sock *sk, struct sk_buff *skb)
3258 {
3259 	u16 family;
3260 	char *addrp;
3261 	int len, err = 0;
3262 	u32 netif_perm, node_perm, node_sid, if_sid, recv_perm = 0;
3263 	u32 sock_sid = 0;
3264 	u16 sock_class = 0;
3265 	struct socket *sock;
3266 	struct net_device *dev;
3267 	struct avc_audit_data ad;
3268 
3269 	family = sk->sk_family;
3270 	if (family != PF_INET && family != PF_INET6)
3271 		goto out;
3272 
3273 	/* Handle mapped IPv4 packets arriving via IPv6 sockets */
3274 	if (family == PF_INET6 && skb->protocol == ntohs(ETH_P_IP))
3275 		family = PF_INET;
3276 
3277  	read_lock_bh(&sk->sk_callback_lock);
3278  	sock = sk->sk_socket;
3279  	if (sock) {
3280  		struct inode *inode;
3281  		inode = SOCK_INODE(sock);
3282  		if (inode) {
3283  			struct inode_security_struct *isec;
3284  			isec = inode->i_security;
3285  			sock_sid = isec->sid;
3286  			sock_class = isec->sclass;
3287  		}
3288  	}
3289  	read_unlock_bh(&sk->sk_callback_lock);
3290  	if (!sock_sid)
3291   		goto out;
3292 
3293 	dev = skb->dev;
3294 	if (!dev)
3295 		goto out;
3296 
3297 	err = sel_netif_sids(dev, &if_sid, NULL);
3298 	if (err)
3299 		goto out;
3300 
3301 	switch (sock_class) {
3302 	case SECCLASS_UDP_SOCKET:
3303 		netif_perm = NETIF__UDP_RECV;
3304 		node_perm = NODE__UDP_RECV;
3305 		recv_perm = UDP_SOCKET__RECV_MSG;
3306 		break;
3307 
3308 	case SECCLASS_TCP_SOCKET:
3309 		netif_perm = NETIF__TCP_RECV;
3310 		node_perm = NODE__TCP_RECV;
3311 		recv_perm = TCP_SOCKET__RECV_MSG;
3312 		break;
3313 
3314 	default:
3315 		netif_perm = NETIF__RAWIP_RECV;
3316 		node_perm = NODE__RAWIP_RECV;
3317 		break;
3318 	}
3319 
3320 	AVC_AUDIT_DATA_INIT(&ad, NET);
3321 	ad.u.net.netif = dev->name;
3322 	ad.u.net.family = family;
3323 
3324 	err = selinux_parse_skb(skb, &ad, &addrp, &len, 1);
3325 	if (err)
3326 		goto out;
3327 
3328 	err = avc_has_perm(sock_sid, if_sid, SECCLASS_NETIF, netif_perm, &ad);
3329 	if (err)
3330 		goto out;
3331 
3332 	/* Fixme: this lookup is inefficient */
3333 	err = security_node_sid(family, addrp, len, &node_sid);
3334 	if (err)
3335 		goto out;
3336 
3337 	err = avc_has_perm(sock_sid, node_sid, SECCLASS_NODE, node_perm, &ad);
3338 	if (err)
3339 		goto out;
3340 
3341 	if (recv_perm) {
3342 		u32 port_sid;
3343 
3344 		/* Fixme: make this more efficient */
3345 		err = security_port_sid(sk->sk_family, sk->sk_type,
3346 		                        sk->sk_protocol, ntohs(ad.u.net.sport),
3347 		                        &port_sid);
3348 		if (err)
3349 			goto out;
3350 
3351 		err = avc_has_perm(sock_sid, port_sid,
3352 				   sock_class, recv_perm, &ad);
3353 	}
3354 out:
3355 	return err;
3356 }
3357 
3358 static int selinux_socket_getpeersec(struct socket *sock, char __user *optval,
3359 				     int __user *optlen, unsigned len)
3360 {
3361 	int err = 0;
3362 	char *scontext;
3363 	u32 scontext_len;
3364 	struct sk_security_struct *ssec;
3365 	struct inode_security_struct *isec;
3366 
3367 	isec = SOCK_INODE(sock)->i_security;
3368 	if (isec->sclass != SECCLASS_UNIX_STREAM_SOCKET) {
3369 		err = -ENOPROTOOPT;
3370 		goto out;
3371 	}
3372 
3373 	ssec = sock->sk->sk_security;
3374 
3375 	err = security_sid_to_context(ssec->peer_sid, &scontext, &scontext_len);
3376 	if (err)
3377 		goto out;
3378 
3379 	if (scontext_len > len) {
3380 		err = -ERANGE;
3381 		goto out_len;
3382 	}
3383 
3384 	if (copy_to_user(optval, scontext, scontext_len))
3385 		err = -EFAULT;
3386 
3387 out_len:
3388 	if (put_user(scontext_len, optlen))
3389 		err = -EFAULT;
3390 
3391 	kfree(scontext);
3392 out:
3393 	return err;
3394 }
3395 
3396 static int selinux_sk_alloc_security(struct sock *sk, int family, int priority)
3397 {
3398 	return sk_alloc_security(sk, family, priority);
3399 }
3400 
3401 static void selinux_sk_free_security(struct sock *sk)
3402 {
3403 	sk_free_security(sk);
3404 }
3405 
3406 static int selinux_nlmsg_perm(struct sock *sk, struct sk_buff *skb)
3407 {
3408 	int err = 0;
3409 	u32 perm;
3410 	struct nlmsghdr *nlh;
3411 	struct socket *sock = sk->sk_socket;
3412 	struct inode_security_struct *isec = SOCK_INODE(sock)->i_security;
3413 
3414 	if (skb->len < NLMSG_SPACE(0)) {
3415 		err = -EINVAL;
3416 		goto out;
3417 	}
3418 	nlh = (struct nlmsghdr *)skb->data;
3419 
3420 	err = selinux_nlmsg_lookup(isec->sclass, nlh->nlmsg_type, &perm);
3421 	if (err) {
3422 		if (err == -EINVAL) {
3423 			audit_log(current->audit_context, AUDIT_SELINUX_ERR,
3424 				  "SELinux:  unrecognized netlink message"
3425 				  " type=%hu for sclass=%hu\n",
3426 				  nlh->nlmsg_type, isec->sclass);
3427 			if (!selinux_enforcing)
3428 				err = 0;
3429 		}
3430 
3431 		/* Ignore */
3432 		if (err == -ENOENT)
3433 			err = 0;
3434 		goto out;
3435 	}
3436 
3437 	err = socket_has_perm(current, sock, perm);
3438 out:
3439 	return err;
3440 }
3441 
3442 #ifdef CONFIG_NETFILTER
3443 
3444 static unsigned int selinux_ip_postroute_last(unsigned int hooknum,
3445                                               struct sk_buff **pskb,
3446                                               const struct net_device *in,
3447                                               const struct net_device *out,
3448                                               int (*okfn)(struct sk_buff *),
3449                                               u16 family)
3450 {
3451 	char *addrp;
3452 	int len, err = NF_ACCEPT;
3453 	u32 netif_perm, node_perm, node_sid, if_sid, send_perm = 0;
3454 	struct sock *sk;
3455 	struct socket *sock;
3456 	struct inode *inode;
3457 	struct sk_buff *skb = *pskb;
3458 	struct inode_security_struct *isec;
3459 	struct avc_audit_data ad;
3460 	struct net_device *dev = (struct net_device *)out;
3461 
3462 	sk = skb->sk;
3463 	if (!sk)
3464 		goto out;
3465 
3466 	sock = sk->sk_socket;
3467 	if (!sock)
3468 		goto out;
3469 
3470 	inode = SOCK_INODE(sock);
3471 	if (!inode)
3472 		goto out;
3473 
3474 	err = sel_netif_sids(dev, &if_sid, NULL);
3475 	if (err)
3476 		goto out;
3477 
3478 	isec = inode->i_security;
3479 
3480 	switch (isec->sclass) {
3481 	case SECCLASS_UDP_SOCKET:
3482 		netif_perm = NETIF__UDP_SEND;
3483 		node_perm = NODE__UDP_SEND;
3484 		send_perm = UDP_SOCKET__SEND_MSG;
3485 		break;
3486 
3487 	case SECCLASS_TCP_SOCKET:
3488 		netif_perm = NETIF__TCP_SEND;
3489 		node_perm = NODE__TCP_SEND;
3490 		send_perm = TCP_SOCKET__SEND_MSG;
3491 		break;
3492 
3493 	default:
3494 		netif_perm = NETIF__RAWIP_SEND;
3495 		node_perm = NODE__RAWIP_SEND;
3496 		break;
3497 	}
3498 
3499 
3500 	AVC_AUDIT_DATA_INIT(&ad, NET);
3501 	ad.u.net.netif = dev->name;
3502 	ad.u.net.family = family;
3503 
3504 	err = selinux_parse_skb(skb, &ad, &addrp,
3505 				&len, 0) ? NF_DROP : NF_ACCEPT;
3506 	if (err != NF_ACCEPT)
3507 		goto out;
3508 
3509 	err = avc_has_perm(isec->sid, if_sid, SECCLASS_NETIF,
3510 	                   netif_perm, &ad) ? NF_DROP : NF_ACCEPT;
3511 	if (err != NF_ACCEPT)
3512 		goto out;
3513 
3514 	/* Fixme: this lookup is inefficient */
3515 	err = security_node_sid(family, addrp, len,
3516 				&node_sid) ? NF_DROP : NF_ACCEPT;
3517 	if (err != NF_ACCEPT)
3518 		goto out;
3519 
3520 	err = avc_has_perm(isec->sid, node_sid, SECCLASS_NODE,
3521 	                   node_perm, &ad) ? NF_DROP : NF_ACCEPT;
3522 	if (err != NF_ACCEPT)
3523 		goto out;
3524 
3525 	if (send_perm) {
3526 		u32 port_sid;
3527 
3528 		/* Fixme: make this more efficient */
3529 		err = security_port_sid(sk->sk_family,
3530 		                        sk->sk_type,
3531 		                        sk->sk_protocol,
3532 		                        ntohs(ad.u.net.dport),
3533 		                        &port_sid) ? NF_DROP : NF_ACCEPT;
3534 		if (err != NF_ACCEPT)
3535 			goto out;
3536 
3537 		err = avc_has_perm(isec->sid, port_sid, isec->sclass,
3538 		                   send_perm, &ad) ? NF_DROP : NF_ACCEPT;
3539 	}
3540 
3541 out:
3542 	return err;
3543 }
3544 
3545 static unsigned int selinux_ipv4_postroute_last(unsigned int hooknum,
3546 						struct sk_buff **pskb,
3547 						const struct net_device *in,
3548 						const struct net_device *out,
3549 						int (*okfn)(struct sk_buff *))
3550 {
3551 	return selinux_ip_postroute_last(hooknum, pskb, in, out, okfn, PF_INET);
3552 }
3553 
3554 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
3555 
3556 static unsigned int selinux_ipv6_postroute_last(unsigned int hooknum,
3557 						struct sk_buff **pskb,
3558 						const struct net_device *in,
3559 						const struct net_device *out,
3560 						int (*okfn)(struct sk_buff *))
3561 {
3562 	return selinux_ip_postroute_last(hooknum, pskb, in, out, okfn, PF_INET6);
3563 }
3564 
3565 #endif	/* IPV6 */
3566 
3567 #endif	/* CONFIG_NETFILTER */
3568 
3569 #else
3570 
3571 static inline int selinux_nlmsg_perm(struct sock *sk, struct sk_buff *skb)
3572 {
3573 	return 0;
3574 }
3575 
3576 #endif	/* CONFIG_SECURITY_NETWORK */
3577 
3578 static int selinux_netlink_send(struct sock *sk, struct sk_buff *skb)
3579 {
3580 	struct task_security_struct *tsec;
3581 	struct av_decision avd;
3582 	int err;
3583 
3584 	err = secondary_ops->netlink_send(sk, skb);
3585 	if (err)
3586 		return err;
3587 
3588 	tsec = current->security;
3589 
3590 	avd.allowed = 0;
3591 	avc_has_perm_noaudit(tsec->sid, tsec->sid,
3592 				SECCLASS_CAPABILITY, ~0, &avd);
3593 	cap_mask(NETLINK_CB(skb).eff_cap, avd.allowed);
3594 
3595 	if (policydb_loaded_version >= POLICYDB_VERSION_NLCLASS)
3596 		err = selinux_nlmsg_perm(sk, skb);
3597 
3598 	return err;
3599 }
3600 
3601 static int selinux_netlink_recv(struct sk_buff *skb)
3602 {
3603 	if (!cap_raised(NETLINK_CB(skb).eff_cap, CAP_NET_ADMIN))
3604 		return -EPERM;
3605 	return 0;
3606 }
3607 
3608 static int ipc_alloc_security(struct task_struct *task,
3609 			      struct kern_ipc_perm *perm,
3610 			      u16 sclass)
3611 {
3612 	struct task_security_struct *tsec = task->security;
3613 	struct ipc_security_struct *isec;
3614 
3615 	isec = kmalloc(sizeof(struct ipc_security_struct), GFP_KERNEL);
3616 	if (!isec)
3617 		return -ENOMEM;
3618 
3619 	memset(isec, 0, sizeof(struct ipc_security_struct));
3620 	isec->magic = SELINUX_MAGIC;
3621 	isec->sclass = sclass;
3622 	isec->ipc_perm = perm;
3623 	if (tsec) {
3624 		isec->sid = tsec->sid;
3625 	} else {
3626 		isec->sid = SECINITSID_UNLABELED;
3627 	}
3628 	perm->security = isec;
3629 
3630 	return 0;
3631 }
3632 
3633 static void ipc_free_security(struct kern_ipc_perm *perm)
3634 {
3635 	struct ipc_security_struct *isec = perm->security;
3636 	if (!isec || isec->magic != SELINUX_MAGIC)
3637 		return;
3638 
3639 	perm->security = NULL;
3640 	kfree(isec);
3641 }
3642 
3643 static int msg_msg_alloc_security(struct msg_msg *msg)
3644 {
3645 	struct msg_security_struct *msec;
3646 
3647 	msec = kmalloc(sizeof(struct msg_security_struct), GFP_KERNEL);
3648 	if (!msec)
3649 		return -ENOMEM;
3650 
3651 	memset(msec, 0, sizeof(struct msg_security_struct));
3652 	msec->magic = SELINUX_MAGIC;
3653 	msec->msg = msg;
3654 	msec->sid = SECINITSID_UNLABELED;
3655 	msg->security = msec;
3656 
3657 	return 0;
3658 }
3659 
3660 static void msg_msg_free_security(struct msg_msg *msg)
3661 {
3662 	struct msg_security_struct *msec = msg->security;
3663 	if (!msec || msec->magic != SELINUX_MAGIC)
3664 		return;
3665 
3666 	msg->security = NULL;
3667 	kfree(msec);
3668 }
3669 
3670 static int ipc_has_perm(struct kern_ipc_perm *ipc_perms,
3671 			u32 perms)
3672 {
3673 	struct task_security_struct *tsec;
3674 	struct ipc_security_struct *isec;
3675 	struct avc_audit_data ad;
3676 
3677 	tsec = current->security;
3678 	isec = ipc_perms->security;
3679 
3680 	AVC_AUDIT_DATA_INIT(&ad, IPC);
3681 	ad.u.ipc_id = ipc_perms->key;
3682 
3683 	return avc_has_perm(tsec->sid, isec->sid, isec->sclass, perms, &ad);
3684 }
3685 
3686 static int selinux_msg_msg_alloc_security(struct msg_msg *msg)
3687 {
3688 	return msg_msg_alloc_security(msg);
3689 }
3690 
3691 static void selinux_msg_msg_free_security(struct msg_msg *msg)
3692 {
3693 	msg_msg_free_security(msg);
3694 }
3695 
3696 /* message queue security operations */
3697 static int selinux_msg_queue_alloc_security(struct msg_queue *msq)
3698 {
3699 	struct task_security_struct *tsec;
3700 	struct ipc_security_struct *isec;
3701 	struct avc_audit_data ad;
3702 	int rc;
3703 
3704 	rc = ipc_alloc_security(current, &msq->q_perm, SECCLASS_MSGQ);
3705 	if (rc)
3706 		return rc;
3707 
3708 	tsec = current->security;
3709 	isec = msq->q_perm.security;
3710 
3711 	AVC_AUDIT_DATA_INIT(&ad, IPC);
3712  	ad.u.ipc_id = msq->q_perm.key;
3713 
3714 	rc = avc_has_perm(tsec->sid, isec->sid, SECCLASS_MSGQ,
3715 			  MSGQ__CREATE, &ad);
3716 	if (rc) {
3717 		ipc_free_security(&msq->q_perm);
3718 		return rc;
3719 	}
3720 	return 0;
3721 }
3722 
3723 static void selinux_msg_queue_free_security(struct msg_queue *msq)
3724 {
3725 	ipc_free_security(&msq->q_perm);
3726 }
3727 
3728 static int selinux_msg_queue_associate(struct msg_queue *msq, int msqflg)
3729 {
3730 	struct task_security_struct *tsec;
3731 	struct ipc_security_struct *isec;
3732 	struct avc_audit_data ad;
3733 
3734 	tsec = current->security;
3735 	isec = msq->q_perm.security;
3736 
3737 	AVC_AUDIT_DATA_INIT(&ad, IPC);
3738 	ad.u.ipc_id = msq->q_perm.key;
3739 
3740 	return avc_has_perm(tsec->sid, isec->sid, SECCLASS_MSGQ,
3741 			    MSGQ__ASSOCIATE, &ad);
3742 }
3743 
3744 static int selinux_msg_queue_msgctl(struct msg_queue *msq, int cmd)
3745 {
3746 	int err;
3747 	int perms;
3748 
3749 	switch(cmd) {
3750 	case IPC_INFO:
3751 	case MSG_INFO:
3752 		/* No specific object, just general system-wide information. */
3753 		return task_has_system(current, SYSTEM__IPC_INFO);
3754 	case IPC_STAT:
3755 	case MSG_STAT:
3756 		perms = MSGQ__GETATTR | MSGQ__ASSOCIATE;
3757 		break;
3758 	case IPC_SET:
3759 		perms = MSGQ__SETATTR;
3760 		break;
3761 	case IPC_RMID:
3762 		perms = MSGQ__DESTROY;
3763 		break;
3764 	default:
3765 		return 0;
3766 	}
3767 
3768 	err = ipc_has_perm(&msq->q_perm, perms);
3769 	return err;
3770 }
3771 
3772 static int selinux_msg_queue_msgsnd(struct msg_queue *msq, struct msg_msg *msg, int msqflg)
3773 {
3774 	struct task_security_struct *tsec;
3775 	struct ipc_security_struct *isec;
3776 	struct msg_security_struct *msec;
3777 	struct avc_audit_data ad;
3778 	int rc;
3779 
3780 	tsec = current->security;
3781 	isec = msq->q_perm.security;
3782 	msec = msg->security;
3783 
3784 	/*
3785 	 * First time through, need to assign label to the message
3786 	 */
3787 	if (msec->sid == SECINITSID_UNLABELED) {
3788 		/*
3789 		 * Compute new sid based on current process and
3790 		 * message queue this message will be stored in
3791 		 */
3792 		rc = security_transition_sid(tsec->sid,
3793 					     isec->sid,
3794 					     SECCLASS_MSG,
3795 					     &msec->sid);
3796 		if (rc)
3797 			return rc;
3798 	}
3799 
3800 	AVC_AUDIT_DATA_INIT(&ad, IPC);
3801 	ad.u.ipc_id = msq->q_perm.key;
3802 
3803 	/* Can this process write to the queue? */
3804 	rc = avc_has_perm(tsec->sid, isec->sid, SECCLASS_MSGQ,
3805 			  MSGQ__WRITE, &ad);
3806 	if (!rc)
3807 		/* Can this process send the message */
3808 		rc = avc_has_perm(tsec->sid, msec->sid,
3809 				  SECCLASS_MSG, MSG__SEND, &ad);
3810 	if (!rc)
3811 		/* Can the message be put in the queue? */
3812 		rc = avc_has_perm(msec->sid, isec->sid,
3813 				  SECCLASS_MSGQ, MSGQ__ENQUEUE, &ad);
3814 
3815 	return rc;
3816 }
3817 
3818 static int selinux_msg_queue_msgrcv(struct msg_queue *msq, struct msg_msg *msg,
3819 				    struct task_struct *target,
3820 				    long type, int mode)
3821 {
3822 	struct task_security_struct *tsec;
3823 	struct ipc_security_struct *isec;
3824 	struct msg_security_struct *msec;
3825 	struct avc_audit_data ad;
3826 	int rc;
3827 
3828 	tsec = target->security;
3829 	isec = msq->q_perm.security;
3830 	msec = msg->security;
3831 
3832 	AVC_AUDIT_DATA_INIT(&ad, IPC);
3833  	ad.u.ipc_id = msq->q_perm.key;
3834 
3835 	rc = avc_has_perm(tsec->sid, isec->sid,
3836 			  SECCLASS_MSGQ, MSGQ__READ, &ad);
3837 	if (!rc)
3838 		rc = avc_has_perm(tsec->sid, msec->sid,
3839 				  SECCLASS_MSG, MSG__RECEIVE, &ad);
3840 	return rc;
3841 }
3842 
3843 /* Shared Memory security operations */
3844 static int selinux_shm_alloc_security(struct shmid_kernel *shp)
3845 {
3846 	struct task_security_struct *tsec;
3847 	struct ipc_security_struct *isec;
3848 	struct avc_audit_data ad;
3849 	int rc;
3850 
3851 	rc = ipc_alloc_security(current, &shp->shm_perm, SECCLASS_SHM);
3852 	if (rc)
3853 		return rc;
3854 
3855 	tsec = current->security;
3856 	isec = shp->shm_perm.security;
3857 
3858 	AVC_AUDIT_DATA_INIT(&ad, IPC);
3859  	ad.u.ipc_id = shp->shm_perm.key;
3860 
3861 	rc = avc_has_perm(tsec->sid, isec->sid, SECCLASS_SHM,
3862 			  SHM__CREATE, &ad);
3863 	if (rc) {
3864 		ipc_free_security(&shp->shm_perm);
3865 		return rc;
3866 	}
3867 	return 0;
3868 }
3869 
3870 static void selinux_shm_free_security(struct shmid_kernel *shp)
3871 {
3872 	ipc_free_security(&shp->shm_perm);
3873 }
3874 
3875 static int selinux_shm_associate(struct shmid_kernel *shp, int shmflg)
3876 {
3877 	struct task_security_struct *tsec;
3878 	struct ipc_security_struct *isec;
3879 	struct avc_audit_data ad;
3880 
3881 	tsec = current->security;
3882 	isec = shp->shm_perm.security;
3883 
3884 	AVC_AUDIT_DATA_INIT(&ad, IPC);
3885 	ad.u.ipc_id = shp->shm_perm.key;
3886 
3887 	return avc_has_perm(tsec->sid, isec->sid, SECCLASS_SHM,
3888 			    SHM__ASSOCIATE, &ad);
3889 }
3890 
3891 /* Note, at this point, shp is locked down */
3892 static int selinux_shm_shmctl(struct shmid_kernel *shp, int cmd)
3893 {
3894 	int perms;
3895 	int err;
3896 
3897 	switch(cmd) {
3898 	case IPC_INFO:
3899 	case SHM_INFO:
3900 		/* No specific object, just general system-wide information. */
3901 		return task_has_system(current, SYSTEM__IPC_INFO);
3902 	case IPC_STAT:
3903 	case SHM_STAT:
3904 		perms = SHM__GETATTR | SHM__ASSOCIATE;
3905 		break;
3906 	case IPC_SET:
3907 		perms = SHM__SETATTR;
3908 		break;
3909 	case SHM_LOCK:
3910 	case SHM_UNLOCK:
3911 		perms = SHM__LOCK;
3912 		break;
3913 	case IPC_RMID:
3914 		perms = SHM__DESTROY;
3915 		break;
3916 	default:
3917 		return 0;
3918 	}
3919 
3920 	err = ipc_has_perm(&shp->shm_perm, perms);
3921 	return err;
3922 }
3923 
3924 static int selinux_shm_shmat(struct shmid_kernel *shp,
3925 			     char __user *shmaddr, int shmflg)
3926 {
3927 	u32 perms;
3928 	int rc;
3929 
3930 	rc = secondary_ops->shm_shmat(shp, shmaddr, shmflg);
3931 	if (rc)
3932 		return rc;
3933 
3934 	if (shmflg & SHM_RDONLY)
3935 		perms = SHM__READ;
3936 	else
3937 		perms = SHM__READ | SHM__WRITE;
3938 
3939 	return ipc_has_perm(&shp->shm_perm, perms);
3940 }
3941 
3942 /* Semaphore security operations */
3943 static int selinux_sem_alloc_security(struct sem_array *sma)
3944 {
3945 	struct task_security_struct *tsec;
3946 	struct ipc_security_struct *isec;
3947 	struct avc_audit_data ad;
3948 	int rc;
3949 
3950 	rc = ipc_alloc_security(current, &sma->sem_perm, SECCLASS_SEM);
3951 	if (rc)
3952 		return rc;
3953 
3954 	tsec = current->security;
3955 	isec = sma->sem_perm.security;
3956 
3957 	AVC_AUDIT_DATA_INIT(&ad, IPC);
3958  	ad.u.ipc_id = sma->sem_perm.key;
3959 
3960 	rc = avc_has_perm(tsec->sid, isec->sid, SECCLASS_SEM,
3961 			  SEM__CREATE, &ad);
3962 	if (rc) {
3963 		ipc_free_security(&sma->sem_perm);
3964 		return rc;
3965 	}
3966 	return 0;
3967 }
3968 
3969 static void selinux_sem_free_security(struct sem_array *sma)
3970 {
3971 	ipc_free_security(&sma->sem_perm);
3972 }
3973 
3974 static int selinux_sem_associate(struct sem_array *sma, int semflg)
3975 {
3976 	struct task_security_struct *tsec;
3977 	struct ipc_security_struct *isec;
3978 	struct avc_audit_data ad;
3979 
3980 	tsec = current->security;
3981 	isec = sma->sem_perm.security;
3982 
3983 	AVC_AUDIT_DATA_INIT(&ad, IPC);
3984 	ad.u.ipc_id = sma->sem_perm.key;
3985 
3986 	return avc_has_perm(tsec->sid, isec->sid, SECCLASS_SEM,
3987 			    SEM__ASSOCIATE, &ad);
3988 }
3989 
3990 /* Note, at this point, sma is locked down */
3991 static int selinux_sem_semctl(struct sem_array *sma, int cmd)
3992 {
3993 	int err;
3994 	u32 perms;
3995 
3996 	switch(cmd) {
3997 	case IPC_INFO:
3998 	case SEM_INFO:
3999 		/* No specific object, just general system-wide information. */
4000 		return task_has_system(current, SYSTEM__IPC_INFO);
4001 	case GETPID:
4002 	case GETNCNT:
4003 	case GETZCNT:
4004 		perms = SEM__GETATTR;
4005 		break;
4006 	case GETVAL:
4007 	case GETALL:
4008 		perms = SEM__READ;
4009 		break;
4010 	case SETVAL:
4011 	case SETALL:
4012 		perms = SEM__WRITE;
4013 		break;
4014 	case IPC_RMID:
4015 		perms = SEM__DESTROY;
4016 		break;
4017 	case IPC_SET:
4018 		perms = SEM__SETATTR;
4019 		break;
4020 	case IPC_STAT:
4021 	case SEM_STAT:
4022 		perms = SEM__GETATTR | SEM__ASSOCIATE;
4023 		break;
4024 	default:
4025 		return 0;
4026 	}
4027 
4028 	err = ipc_has_perm(&sma->sem_perm, perms);
4029 	return err;
4030 }
4031 
4032 static int selinux_sem_semop(struct sem_array *sma,
4033 			     struct sembuf *sops, unsigned nsops, int alter)
4034 {
4035 	u32 perms;
4036 
4037 	if (alter)
4038 		perms = SEM__READ | SEM__WRITE;
4039 	else
4040 		perms = SEM__READ;
4041 
4042 	return ipc_has_perm(&sma->sem_perm, perms);
4043 }
4044 
4045 static int selinux_ipc_permission(struct kern_ipc_perm *ipcp, short flag)
4046 {
4047 	u32 av = 0;
4048 
4049 	av = 0;
4050 	if (flag & S_IRUGO)
4051 		av |= IPC__UNIX_READ;
4052 	if (flag & S_IWUGO)
4053 		av |= IPC__UNIX_WRITE;
4054 
4055 	if (av == 0)
4056 		return 0;
4057 
4058 	return ipc_has_perm(ipcp, av);
4059 }
4060 
4061 /* module stacking operations */
4062 static int selinux_register_security (const char *name, struct security_operations *ops)
4063 {
4064 	if (secondary_ops != original_ops) {
4065 		printk(KERN_INFO "%s:  There is already a secondary security "
4066 		       "module registered.\n", __FUNCTION__);
4067 		return -EINVAL;
4068  	}
4069 
4070 	secondary_ops = ops;
4071 
4072 	printk(KERN_INFO "%s:  Registering secondary module %s\n",
4073 	       __FUNCTION__,
4074 	       name);
4075 
4076 	return 0;
4077 }
4078 
4079 static int selinux_unregister_security (const char *name, struct security_operations *ops)
4080 {
4081 	if (ops != secondary_ops) {
4082 		printk (KERN_INFO "%s:  trying to unregister a security module "
4083 		        "that is not registered.\n", __FUNCTION__);
4084 		return -EINVAL;
4085 	}
4086 
4087 	secondary_ops = original_ops;
4088 
4089 	return 0;
4090 }
4091 
4092 static void selinux_d_instantiate (struct dentry *dentry, struct inode *inode)
4093 {
4094 	if (inode)
4095 		inode_doinit_with_dentry(inode, dentry);
4096 }
4097 
4098 static int selinux_getprocattr(struct task_struct *p,
4099 			       char *name, void *value, size_t size)
4100 {
4101 	struct task_security_struct *tsec;
4102 	u32 sid, len;
4103 	char *context;
4104 	int error;
4105 
4106 	if (current != p) {
4107 		error = task_has_perm(current, p, PROCESS__GETATTR);
4108 		if (error)
4109 			return error;
4110 	}
4111 
4112 	if (!size)
4113 		return -ERANGE;
4114 
4115 	tsec = p->security;
4116 
4117 	if (!strcmp(name, "current"))
4118 		sid = tsec->sid;
4119 	else if (!strcmp(name, "prev"))
4120 		sid = tsec->osid;
4121 	else if (!strcmp(name, "exec"))
4122 		sid = tsec->exec_sid;
4123 	else if (!strcmp(name, "fscreate"))
4124 		sid = tsec->create_sid;
4125 	else
4126 		return -EINVAL;
4127 
4128 	if (!sid)
4129 		return 0;
4130 
4131 	error = security_sid_to_context(sid, &context, &len);
4132 	if (error)
4133 		return error;
4134 	if (len > size) {
4135 		kfree(context);
4136 		return -ERANGE;
4137 	}
4138 	memcpy(value, context, len);
4139 	kfree(context);
4140 	return len;
4141 }
4142 
4143 static int selinux_setprocattr(struct task_struct *p,
4144 			       char *name, void *value, size_t size)
4145 {
4146 	struct task_security_struct *tsec;
4147 	u32 sid = 0;
4148 	int error;
4149 	char *str = value;
4150 
4151 	if (current != p) {
4152 		/* SELinux only allows a process to change its own
4153 		   security attributes. */
4154 		return -EACCES;
4155 	}
4156 
4157 	/*
4158 	 * Basic control over ability to set these attributes at all.
4159 	 * current == p, but we'll pass them separately in case the
4160 	 * above restriction is ever removed.
4161 	 */
4162 	if (!strcmp(name, "exec"))
4163 		error = task_has_perm(current, p, PROCESS__SETEXEC);
4164 	else if (!strcmp(name, "fscreate"))
4165 		error = task_has_perm(current, p, PROCESS__SETFSCREATE);
4166 	else if (!strcmp(name, "current"))
4167 		error = task_has_perm(current, p, PROCESS__SETCURRENT);
4168 	else
4169 		error = -EINVAL;
4170 	if (error)
4171 		return error;
4172 
4173 	/* Obtain a SID for the context, if one was specified. */
4174 	if (size && str[1] && str[1] != '\n') {
4175 		if (str[size-1] == '\n') {
4176 			str[size-1] = 0;
4177 			size--;
4178 		}
4179 		error = security_context_to_sid(value, size, &sid);
4180 		if (error)
4181 			return error;
4182 	}
4183 
4184 	/* Permission checking based on the specified context is
4185 	   performed during the actual operation (execve,
4186 	   open/mkdir/...), when we know the full context of the
4187 	   operation.  See selinux_bprm_set_security for the execve
4188 	   checks and may_create for the file creation checks. The
4189 	   operation will then fail if the context is not permitted. */
4190 	tsec = p->security;
4191 	if (!strcmp(name, "exec"))
4192 		tsec->exec_sid = sid;
4193 	else if (!strcmp(name, "fscreate"))
4194 		tsec->create_sid = sid;
4195 	else if (!strcmp(name, "current")) {
4196 		struct av_decision avd;
4197 
4198 		if (sid == 0)
4199 			return -EINVAL;
4200 
4201 		/* Only allow single threaded processes to change context */
4202 		if (atomic_read(&p->mm->mm_users) != 1) {
4203 			struct task_struct *g, *t;
4204 			struct mm_struct *mm = p->mm;
4205 			read_lock(&tasklist_lock);
4206 			do_each_thread(g, t)
4207 				if (t->mm == mm && t != p) {
4208 					read_unlock(&tasklist_lock);
4209 					return -EPERM;
4210 				}
4211 			while_each_thread(g, t);
4212 			read_unlock(&tasklist_lock);
4213                 }
4214 
4215 		/* Check permissions for the transition. */
4216 		error = avc_has_perm(tsec->sid, sid, SECCLASS_PROCESS,
4217 		                     PROCESS__DYNTRANSITION, NULL);
4218 		if (error)
4219 			return error;
4220 
4221 		/* Check for ptracing, and update the task SID if ok.
4222 		   Otherwise, leave SID unchanged and fail. */
4223 		task_lock(p);
4224 		if (p->ptrace & PT_PTRACED) {
4225 			error = avc_has_perm_noaudit(tsec->ptrace_sid, sid,
4226 						     SECCLASS_PROCESS,
4227 						     PROCESS__PTRACE, &avd);
4228 			if (!error)
4229 				tsec->sid = sid;
4230 			task_unlock(p);
4231 			avc_audit(tsec->ptrace_sid, sid, SECCLASS_PROCESS,
4232 				  PROCESS__PTRACE, &avd, error, NULL);
4233 			if (error)
4234 				return error;
4235 		} else {
4236 			tsec->sid = sid;
4237 			task_unlock(p);
4238 		}
4239 	}
4240 	else
4241 		return -EINVAL;
4242 
4243 	return size;
4244 }
4245 
4246 static struct security_operations selinux_ops = {
4247 	.ptrace =			selinux_ptrace,
4248 	.capget =			selinux_capget,
4249 	.capset_check =			selinux_capset_check,
4250 	.capset_set =			selinux_capset_set,
4251 	.sysctl =			selinux_sysctl,
4252 	.capable =			selinux_capable,
4253 	.quotactl =			selinux_quotactl,
4254 	.quota_on =			selinux_quota_on,
4255 	.syslog =			selinux_syslog,
4256 	.vm_enough_memory =		selinux_vm_enough_memory,
4257 
4258 	.netlink_send =			selinux_netlink_send,
4259         .netlink_recv =			selinux_netlink_recv,
4260 
4261 	.bprm_alloc_security =		selinux_bprm_alloc_security,
4262 	.bprm_free_security =		selinux_bprm_free_security,
4263 	.bprm_apply_creds =		selinux_bprm_apply_creds,
4264 	.bprm_post_apply_creds =	selinux_bprm_post_apply_creds,
4265 	.bprm_set_security =		selinux_bprm_set_security,
4266 	.bprm_check_security =		selinux_bprm_check_security,
4267 	.bprm_secureexec =		selinux_bprm_secureexec,
4268 
4269 	.sb_alloc_security =		selinux_sb_alloc_security,
4270 	.sb_free_security =		selinux_sb_free_security,
4271 	.sb_copy_data =			selinux_sb_copy_data,
4272 	.sb_kern_mount =	        selinux_sb_kern_mount,
4273 	.sb_statfs =			selinux_sb_statfs,
4274 	.sb_mount =			selinux_mount,
4275 	.sb_umount =			selinux_umount,
4276 
4277 	.inode_alloc_security =		selinux_inode_alloc_security,
4278 	.inode_free_security =		selinux_inode_free_security,
4279 	.inode_create =			selinux_inode_create,
4280 	.inode_post_create =		selinux_inode_post_create,
4281 	.inode_link =			selinux_inode_link,
4282 	.inode_post_link =		selinux_inode_post_link,
4283 	.inode_unlink =			selinux_inode_unlink,
4284 	.inode_symlink =		selinux_inode_symlink,
4285 	.inode_post_symlink =		selinux_inode_post_symlink,
4286 	.inode_mkdir =			selinux_inode_mkdir,
4287 	.inode_post_mkdir =		selinux_inode_post_mkdir,
4288 	.inode_rmdir =			selinux_inode_rmdir,
4289 	.inode_mknod =			selinux_inode_mknod,
4290 	.inode_post_mknod =		selinux_inode_post_mknod,
4291 	.inode_rename =			selinux_inode_rename,
4292 	.inode_post_rename =		selinux_inode_post_rename,
4293 	.inode_readlink =		selinux_inode_readlink,
4294 	.inode_follow_link =		selinux_inode_follow_link,
4295 	.inode_permission =		selinux_inode_permission,
4296 	.inode_setattr =		selinux_inode_setattr,
4297 	.inode_getattr =		selinux_inode_getattr,
4298 	.inode_setxattr =		selinux_inode_setxattr,
4299 	.inode_post_setxattr =		selinux_inode_post_setxattr,
4300 	.inode_getxattr =		selinux_inode_getxattr,
4301 	.inode_listxattr =		selinux_inode_listxattr,
4302 	.inode_removexattr =		selinux_inode_removexattr,
4303 	.inode_getsecurity =            selinux_inode_getsecurity,
4304 	.inode_setsecurity =            selinux_inode_setsecurity,
4305 	.inode_listsecurity =           selinux_inode_listsecurity,
4306 
4307 	.file_permission =		selinux_file_permission,
4308 	.file_alloc_security =		selinux_file_alloc_security,
4309 	.file_free_security =		selinux_file_free_security,
4310 	.file_ioctl =			selinux_file_ioctl,
4311 	.file_mmap =			selinux_file_mmap,
4312 	.file_mprotect =		selinux_file_mprotect,
4313 	.file_lock =			selinux_file_lock,
4314 	.file_fcntl =			selinux_file_fcntl,
4315 	.file_set_fowner =		selinux_file_set_fowner,
4316 	.file_send_sigiotask =		selinux_file_send_sigiotask,
4317 	.file_receive =			selinux_file_receive,
4318 
4319 	.task_create =			selinux_task_create,
4320 	.task_alloc_security =		selinux_task_alloc_security,
4321 	.task_free_security =		selinux_task_free_security,
4322 	.task_setuid =			selinux_task_setuid,
4323 	.task_post_setuid =		selinux_task_post_setuid,
4324 	.task_setgid =			selinux_task_setgid,
4325 	.task_setpgid =			selinux_task_setpgid,
4326 	.task_getpgid =			selinux_task_getpgid,
4327 	.task_getsid =		        selinux_task_getsid,
4328 	.task_setgroups =		selinux_task_setgroups,
4329 	.task_setnice =			selinux_task_setnice,
4330 	.task_setrlimit =		selinux_task_setrlimit,
4331 	.task_setscheduler =		selinux_task_setscheduler,
4332 	.task_getscheduler =		selinux_task_getscheduler,
4333 	.task_kill =			selinux_task_kill,
4334 	.task_wait =			selinux_task_wait,
4335 	.task_prctl =			selinux_task_prctl,
4336 	.task_reparent_to_init =	selinux_task_reparent_to_init,
4337 	.task_to_inode =                selinux_task_to_inode,
4338 
4339 	.ipc_permission =		selinux_ipc_permission,
4340 
4341 	.msg_msg_alloc_security =	selinux_msg_msg_alloc_security,
4342 	.msg_msg_free_security =	selinux_msg_msg_free_security,
4343 
4344 	.msg_queue_alloc_security =	selinux_msg_queue_alloc_security,
4345 	.msg_queue_free_security =	selinux_msg_queue_free_security,
4346 	.msg_queue_associate =		selinux_msg_queue_associate,
4347 	.msg_queue_msgctl =		selinux_msg_queue_msgctl,
4348 	.msg_queue_msgsnd =		selinux_msg_queue_msgsnd,
4349 	.msg_queue_msgrcv =		selinux_msg_queue_msgrcv,
4350 
4351 	.shm_alloc_security =		selinux_shm_alloc_security,
4352 	.shm_free_security =		selinux_shm_free_security,
4353 	.shm_associate =		selinux_shm_associate,
4354 	.shm_shmctl =			selinux_shm_shmctl,
4355 	.shm_shmat =			selinux_shm_shmat,
4356 
4357 	.sem_alloc_security = 		selinux_sem_alloc_security,
4358 	.sem_free_security =  		selinux_sem_free_security,
4359 	.sem_associate =		selinux_sem_associate,
4360 	.sem_semctl =			selinux_sem_semctl,
4361 	.sem_semop =			selinux_sem_semop,
4362 
4363 	.register_security =		selinux_register_security,
4364 	.unregister_security =		selinux_unregister_security,
4365 
4366 	.d_instantiate =                selinux_d_instantiate,
4367 
4368 	.getprocattr =                  selinux_getprocattr,
4369 	.setprocattr =                  selinux_setprocattr,
4370 
4371 #ifdef CONFIG_SECURITY_NETWORK
4372         .unix_stream_connect =		selinux_socket_unix_stream_connect,
4373 	.unix_may_send =		selinux_socket_unix_may_send,
4374 
4375 	.socket_create =		selinux_socket_create,
4376 	.socket_post_create =		selinux_socket_post_create,
4377 	.socket_bind =			selinux_socket_bind,
4378 	.socket_connect =		selinux_socket_connect,
4379 	.socket_listen =		selinux_socket_listen,
4380 	.socket_accept =		selinux_socket_accept,
4381 	.socket_sendmsg =		selinux_socket_sendmsg,
4382 	.socket_recvmsg =		selinux_socket_recvmsg,
4383 	.socket_getsockname =		selinux_socket_getsockname,
4384 	.socket_getpeername =		selinux_socket_getpeername,
4385 	.socket_getsockopt =		selinux_socket_getsockopt,
4386 	.socket_setsockopt =		selinux_socket_setsockopt,
4387 	.socket_shutdown =		selinux_socket_shutdown,
4388 	.socket_sock_rcv_skb =		selinux_socket_sock_rcv_skb,
4389 	.socket_getpeersec =		selinux_socket_getpeersec,
4390 	.sk_alloc_security =		selinux_sk_alloc_security,
4391 	.sk_free_security =		selinux_sk_free_security,
4392 #endif
4393 };
4394 
4395 static __init int selinux_init(void)
4396 {
4397 	struct task_security_struct *tsec;
4398 
4399 	if (!selinux_enabled) {
4400 		printk(KERN_INFO "SELinux:  Disabled at boot.\n");
4401 		return 0;
4402 	}
4403 
4404 	printk(KERN_INFO "SELinux:  Initializing.\n");
4405 
4406 	/* Set the security state for the initial task. */
4407 	if (task_alloc_security(current))
4408 		panic("SELinux:  Failed to initialize initial task.\n");
4409 	tsec = current->security;
4410 	tsec->osid = tsec->sid = SECINITSID_KERNEL;
4411 
4412 	avc_init();
4413 
4414 	original_ops = secondary_ops = security_ops;
4415 	if (!secondary_ops)
4416 		panic ("SELinux: No initial security operations\n");
4417 	if (register_security (&selinux_ops))
4418 		panic("SELinux: Unable to register with kernel.\n");
4419 
4420 	if (selinux_enforcing) {
4421 		printk(KERN_INFO "SELinux:  Starting in enforcing mode\n");
4422 	} else {
4423 		printk(KERN_INFO "SELinux:  Starting in permissive mode\n");
4424 	}
4425 	return 0;
4426 }
4427 
4428 void selinux_complete_init(void)
4429 {
4430 	printk(KERN_INFO "SELinux:  Completing initialization.\n");
4431 
4432 	/* Set up any superblocks initialized prior to the policy load. */
4433 	printk(KERN_INFO "SELinux:  Setting up existing superblocks.\n");
4434 	spin_lock(&sb_security_lock);
4435 next_sb:
4436 	if (!list_empty(&superblock_security_head)) {
4437 		struct superblock_security_struct *sbsec =
4438 				list_entry(superblock_security_head.next,
4439 				           struct superblock_security_struct,
4440 				           list);
4441 		struct super_block *sb = sbsec->sb;
4442 		spin_lock(&sb_lock);
4443 		sb->s_count++;
4444 		spin_unlock(&sb_lock);
4445 		spin_unlock(&sb_security_lock);
4446 		down_read(&sb->s_umount);
4447 		if (sb->s_root)
4448 			superblock_doinit(sb, NULL);
4449 		drop_super(sb);
4450 		spin_lock(&sb_security_lock);
4451 		list_del_init(&sbsec->list);
4452 		goto next_sb;
4453 	}
4454 	spin_unlock(&sb_security_lock);
4455 }
4456 
4457 /* SELinux requires early initialization in order to label
4458    all processes and objects when they are created. */
4459 security_initcall(selinux_init);
4460 
4461 #if defined(CONFIG_SECURITY_NETWORK) && defined(CONFIG_NETFILTER)
4462 
4463 static struct nf_hook_ops selinux_ipv4_op = {
4464 	.hook =		selinux_ipv4_postroute_last,
4465 	.owner =	THIS_MODULE,
4466 	.pf =		PF_INET,
4467 	.hooknum =	NF_IP_POST_ROUTING,
4468 	.priority =	NF_IP_PRI_SELINUX_LAST,
4469 };
4470 
4471 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
4472 
4473 static struct nf_hook_ops selinux_ipv6_op = {
4474 	.hook =		selinux_ipv6_postroute_last,
4475 	.owner =	THIS_MODULE,
4476 	.pf =		PF_INET6,
4477 	.hooknum =	NF_IP6_POST_ROUTING,
4478 	.priority =	NF_IP6_PRI_SELINUX_LAST,
4479 };
4480 
4481 #endif	/* IPV6 */
4482 
4483 static int __init selinux_nf_ip_init(void)
4484 {
4485 	int err = 0;
4486 
4487 	if (!selinux_enabled)
4488 		goto out;
4489 
4490 	printk(KERN_INFO "SELinux:  Registering netfilter hooks\n");
4491 
4492 	err = nf_register_hook(&selinux_ipv4_op);
4493 	if (err)
4494 		panic("SELinux: nf_register_hook for IPv4: error %d\n", err);
4495 
4496 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
4497 
4498 	err = nf_register_hook(&selinux_ipv6_op);
4499 	if (err)
4500 		panic("SELinux: nf_register_hook for IPv6: error %d\n", err);
4501 
4502 #endif	/* IPV6 */
4503 out:
4504 	return err;
4505 }
4506 
4507 __initcall(selinux_nf_ip_init);
4508 
4509 #ifdef CONFIG_SECURITY_SELINUX_DISABLE
4510 static void selinux_nf_ip_exit(void)
4511 {
4512 	printk(KERN_INFO "SELinux:  Unregistering netfilter hooks\n");
4513 
4514 	nf_unregister_hook(&selinux_ipv4_op);
4515 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
4516 	nf_unregister_hook(&selinux_ipv6_op);
4517 #endif	/* IPV6 */
4518 }
4519 #endif
4520 
4521 #else /* CONFIG_SECURITY_NETWORK && CONFIG_NETFILTER */
4522 
4523 #ifdef CONFIG_SECURITY_SELINUX_DISABLE
4524 #define selinux_nf_ip_exit()
4525 #endif
4526 
4527 #endif /* CONFIG_SECURITY_NETWORK && CONFIG_NETFILTER */
4528 
4529 #ifdef CONFIG_SECURITY_SELINUX_DISABLE
4530 int selinux_disable(void)
4531 {
4532 	extern void exit_sel_fs(void);
4533 	static int selinux_disabled = 0;
4534 
4535 	if (ss_initialized) {
4536 		/* Not permitted after initial policy load. */
4537 		return -EINVAL;
4538 	}
4539 
4540 	if (selinux_disabled) {
4541 		/* Only do this once. */
4542 		return -EINVAL;
4543 	}
4544 
4545 	printk(KERN_INFO "SELinux:  Disabled at runtime.\n");
4546 
4547 	selinux_disabled = 1;
4548 
4549 	/* Reset security_ops to the secondary module, dummy or capability. */
4550 	security_ops = secondary_ops;
4551 
4552 	/* Unregister netfilter hooks. */
4553 	selinux_nf_ip_exit();
4554 
4555 	/* Unregister selinuxfs. */
4556 	exit_sel_fs();
4557 
4558 	return 0;
4559 }
4560 #endif
4561 
4562 
4563