hooks.c 141.6 KB
Newer Older
L
Linus Torvalds 已提交
1 2 3 4 5 6
/*
 *  NSA Security-Enhanced Linux (SELinux) security module
 *
 *  This file contains the SELinux hook function implementations.
 *
 *  Authors:  Stephen Smalley, <sds@epoch.ncsc.mil>
7 8 9
 *	      Chris Vance, <cvance@nai.com>
 *	      Wayne Salamon, <wsalamon@nai.com>
 *	      James Morris <jmorris@redhat.com>
L
Linus Torvalds 已提交
10 11
 *
 *  Copyright (C) 2001,2002 Networks Associates Technology, Inc.
12 13
 *  Copyright (C) 2003-2008 Red Hat, Inc., James Morris <jmorris@redhat.com>
 *					   Eric Paris <eparis@redhat.com>
L
Linus Torvalds 已提交
14
 *  Copyright (C) 2004-2005 Trusted Computer Solutions, Inc.
15
 *			    <dgoeddel@trustedcs.com>
16
 *  Copyright (C) 2006, 2007 Hewlett-Packard Development Company, L.P.
17
 *		Paul Moore <paul.moore@hp.com>
18
 *  Copyright (C) 2007 Hitachi Software Engineering Co., Ltd.
19
 *		       Yuichi Nakamura <ynakam@hitachisoft.jp>
L
Linus Torvalds 已提交
20 21 22
 *
 *	This program is free software; you can redistribute it and/or modify
 *	it under the terms of the GNU General Public License version 2,
23
 *	as published by the Free Software Foundation.
L
Linus Torvalds 已提交
24 25 26 27
 */

#include <linux/init.h>
#include <linux/kernel.h>
28
#include <linux/tracehook.h>
L
Linus Torvalds 已提交
29 30 31 32 33 34 35 36 37 38 39 40 41 42
#include <linux/errno.h>
#include <linux/sched.h>
#include <linux/security.h>
#include <linux/xattr.h>
#include <linux/capability.h>
#include <linux/unistd.h>
#include <linux/mm.h>
#include <linux/mman.h>
#include <linux/slab.h>
#include <linux/pagemap.h>
#include <linux/swap.h>
#include <linux/spinlock.h>
#include <linux/syscalls.h>
#include <linux/file.h>
A
Al Viro 已提交
43
#include <linux/fdtable.h>
L
Linus Torvalds 已提交
44 45 46 47 48 49 50
#include <linux/namei.h>
#include <linux/mount.h>
#include <linux/proc_fs.h>
#include <linux/netfilter_ipv4.h>
#include <linux/netfilter_ipv6.h>
#include <linux/tty.h>
#include <net/icmp.h>
51
#include <net/ip.h>		/* for local_port_range[] */
L
Linus Torvalds 已提交
52
#include <net/tcp.h>		/* struct or_callable used in sock_rcv_skb */
53
#include <net/net_namespace.h>
54
#include <net/netlabel.h>
55
#include <linux/uaccess.h>
L
Linus Torvalds 已提交
56
#include <asm/ioctls.h>
57
#include <asm/atomic.h>
L
Linus Torvalds 已提交
58 59 60 61 62 63
#include <linux/bitops.h>
#include <linux/interrupt.h>
#include <linux/netdevice.h>	/* for network interface checks */
#include <linux/netlink.h>
#include <linux/tcp.h>
#include <linux/udp.h>
J
James Morris 已提交
64
#include <linux/dccp.h>
L
Linus Torvalds 已提交
65 66 67 68 69 70 71 72 73 74
#include <linux/quota.h>
#include <linux/un.h>		/* for Unix socket types */
#include <net/af_unix.h>	/* for Unix socket types */
#include <linux/parser.h>
#include <linux/nfs_mount.h>
#include <net/ipv6.h>
#include <linux/hugetlb.h>
#include <linux/personality.h>
#include <linux/sysctl.h>
#include <linux/audit.h>
75
#include <linux/string.h>
C
Catherine Zhang 已提交
76
#include <linux/selinux.h>
77
#include <linux/mutex.h>
78
#include <linux/posix-timers.h>
L
Linus Torvalds 已提交
79 80 81 82

#include "avc.h"
#include "objsec.h"
#include "netif.h"
83
#include "netnode.h"
P
Paul Moore 已提交
84
#include "netport.h"
85
#include "xfrm.h"
86
#include "netlabel.h"
87
#include "audit.h"
L
Linus Torvalds 已提交
88 89 90 91

#define XATTR_SELINUX_SUFFIX "selinux"
#define XATTR_NAME_SELINUX XATTR_SECURITY_PREFIX XATTR_SELINUX_SUFFIX

92 93
#define NUM_SEL_MNT_OPTS 4

L
Linus Torvalds 已提交
94 95
extern unsigned int policydb_loaded_version;
extern int selinux_nlmsg_lookup(u16 sclass, u16 nlmsg_type, u32 *perm);
96
extern int selinux_compat_net;
97
extern struct security_operations *security_ops;
L
Linus Torvalds 已提交
98

99 100 101
/* SECMARK reference count */
atomic_t selinux_secmark_refcount = ATOMIC_INIT(0);

L
Linus Torvalds 已提交
102
#ifdef CONFIG_SECURITY_SELINUX_DEVELOP
103
int selinux_enforcing;
L
Linus Torvalds 已提交
104 105 106

static int __init enforcing_setup(char *str)
{
107 108 109
	unsigned long enforcing;
	if (!strict_strtoul(str, 0, &enforcing))
		selinux_enforcing = enforcing ? 1 : 0;
L
Linus Torvalds 已提交
110 111 112 113 114 115 116 117 118 119
	return 1;
}
__setup("enforcing=", enforcing_setup);
#endif

#ifdef CONFIG_SECURITY_SELINUX_BOOTPARAM
int selinux_enabled = CONFIG_SECURITY_SELINUX_BOOTPARAM_VALUE;

static int __init selinux_enabled_setup(char *str)
{
120 121 122
	unsigned long enabled;
	if (!strict_strtoul(str, 0, &enabled))
		selinux_enabled = enabled ? 1 : 0;
L
Linus Torvalds 已提交
123 124 125
	return 1;
}
__setup("selinux=", selinux_enabled_setup);
126 127
#else
int selinux_enabled = 1;
L
Linus Torvalds 已提交
128 129 130
#endif


131 132 133 134
/*
 * Minimal support for a secondary security module,
 * just to allow the use of the capability module.
 */
135
static struct security_operations *secondary_ops;
L
Linus Torvalds 已提交
136 137 138 139 140 141

/* Lists of inode and superblock security structures initialized
   before the policy was loaded. */
static LIST_HEAD(superblock_security_head);
static DEFINE_SPINLOCK(sb_security_lock);

142
static struct kmem_cache *sel_inode_cache;
143

144 145 146 147 148 149 150 151 152 153 154 155 156 157 158
/**
 * selinux_secmark_enabled - Check to see if SECMARK is currently enabled
 *
 * Description:
 * This function checks the SECMARK reference counter to see if any SECMARK
 * targets are currently configured, if the reference counter is greater than
 * zero SECMARK is considered to be enabled.  Returns true (1) if SECMARK is
 * enabled, false (0) if SECMARK is disabled.
 *
 */
static int selinux_secmark_enabled(void)
{
	return (atomic_read(&selinux_secmark_refcount) > 0);
}

D
David Howells 已提交
159 160 161 162
/*
 * initialise the security for the init task
 */
static void cred_init_security(void)
L
Linus Torvalds 已提交
163
{
164
	struct cred *cred = (struct cred *) current->real_cred;
L
Linus Torvalds 已提交
165 166
	struct task_security_struct *tsec;

J
James Morris 已提交
167
	tsec = kzalloc(sizeof(struct task_security_struct), GFP_KERNEL);
L
Linus Torvalds 已提交
168
	if (!tsec)
D
David Howells 已提交
169
		panic("SELinux:  Failed to initialize initial task.\n");
L
Linus Torvalds 已提交
170

D
David Howells 已提交
171
	tsec->osid = tsec->sid = SECINITSID_KERNEL;
172
	cred->security = tsec;
L
Linus Torvalds 已提交
173 174
}

175 176 177 178 179 180 181 182 183 184 185
/*
 * get the security ID of a set of credentials
 */
static inline u32 cred_sid(const struct cred *cred)
{
	const struct task_security_struct *tsec;

	tsec = cred->security;
	return tsec->sid;
}

186
/*
187
 * get the objective security ID of a task
188 189 190 191 192 193
 */
static inline u32 task_sid(const struct task_struct *task)
{
	u32 sid;

	rcu_read_lock();
194
	sid = cred_sid(__task_cred(task));
195 196 197 198 199
	rcu_read_unlock();
	return sid;
}

/*
200
 * get the subjective security ID of the current task
201 202 203 204 205 206 207 208
 */
static inline u32 current_sid(void)
{
	const struct task_security_struct *tsec = current_cred()->security;

	return tsec->sid;
}

209 210
/* Allocate and free functions for each kind of security blob. */

L
Linus Torvalds 已提交
211 212 213
static int inode_alloc_security(struct inode *inode)
{
	struct inode_security_struct *isec;
214
	u32 sid = current_sid();
L
Linus Torvalds 已提交
215

216
	isec = kmem_cache_zalloc(sel_inode_cache, GFP_NOFS);
L
Linus Torvalds 已提交
217 218 219
	if (!isec)
		return -ENOMEM;

220
	mutex_init(&isec->lock);
L
Linus Torvalds 已提交
221 222 223 224
	INIT_LIST_HEAD(&isec->list);
	isec->inode = inode;
	isec->sid = SECINITSID_UNLABELED;
	isec->sclass = SECCLASS_FILE;
225
	isec->task_sid = sid;
L
Linus Torvalds 已提交
226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241
	inode->i_security = isec;

	return 0;
}

static void inode_free_security(struct inode *inode)
{
	struct inode_security_struct *isec = inode->i_security;
	struct superblock_security_struct *sbsec = inode->i_sb->s_security;

	spin_lock(&sbsec->isec_lock);
	if (!list_empty(&isec->list))
		list_del_init(&isec->list);
	spin_unlock(&sbsec->isec_lock);

	inode->i_security = NULL;
242
	kmem_cache_free(sel_inode_cache, isec);
L
Linus Torvalds 已提交
243 244 245 246 247
}

static int file_alloc_security(struct file *file)
{
	struct file_security_struct *fsec;
248
	u32 sid = current_sid();
L
Linus Torvalds 已提交
249

250
	fsec = kzalloc(sizeof(struct file_security_struct), GFP_KERNEL);
L
Linus Torvalds 已提交
251 252 253
	if (!fsec)
		return -ENOMEM;

254 255
	fsec->sid = sid;
	fsec->fown_sid = sid;
L
Linus Torvalds 已提交
256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271
	file->f_security = fsec;

	return 0;
}

static void file_free_security(struct file *file)
{
	struct file_security_struct *fsec = file->f_security;
	file->f_security = NULL;
	kfree(fsec);
}

static int superblock_alloc_security(struct super_block *sb)
{
	struct superblock_security_struct *sbsec;

J
James Morris 已提交
272
	sbsec = kzalloc(sizeof(struct superblock_security_struct), GFP_KERNEL);
L
Linus Torvalds 已提交
273 274 275
	if (!sbsec)
		return -ENOMEM;

276
	mutex_init(&sbsec->lock);
L
Linus Torvalds 已提交
277 278 279 280 281 282
	INIT_LIST_HEAD(&sbsec->list);
	INIT_LIST_HEAD(&sbsec->isec_head);
	spin_lock_init(&sbsec->isec_lock);
	sbsec->sb = sb;
	sbsec->sid = SECINITSID_UNLABELED;
	sbsec->def_sid = SECINITSID_FILE;
283
	sbsec->mntpoint_sid = SECINITSID_UNLABELED;
L
Linus Torvalds 已提交
284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301
	sb->s_security = sbsec;

	return 0;
}

static void superblock_free_security(struct super_block *sb)
{
	struct superblock_security_struct *sbsec = sb->s_security;

	spin_lock(&sb_security_lock);
	if (!list_empty(&sbsec->list))
		list_del_init(&sbsec->list);
	spin_unlock(&sb_security_lock);

	sb->s_security = NULL;
	kfree(sbsec);
}

A
Al Viro 已提交
302
static int sk_alloc_security(struct sock *sk, int family, gfp_t priority)
L
Linus Torvalds 已提交
303 304 305
{
	struct sk_security_struct *ssec;

J
James Morris 已提交
306
	ssec = kzalloc(sizeof(*ssec), priority);
L
Linus Torvalds 已提交
307 308 309 310
	if (!ssec)
		return -ENOMEM;

	ssec->peer_sid = SECINITSID_UNLABELED;
311
	ssec->sid = SECINITSID_UNLABELED;
L
Linus Torvalds 已提交
312 313
	sk->sk_security = ssec;

314
	selinux_netlbl_sk_security_reset(ssec, family);
315

L
Linus Torvalds 已提交
316 317 318 319 320 321 322 323
	return 0;
}

static void sk_free_security(struct sock *sk)
{
	struct sk_security_struct *ssec = sk->sk_security;

	sk->sk_security = NULL;
324
	selinux_netlbl_sk_security_free(ssec);
L
Linus Torvalds 已提交
325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350
	kfree(ssec);
}

/* The security server must be initialized before
   any labeling or access decisions can be provided. */
extern int ss_initialized;

/* The file system's label must be initialized prior to use. */

static char *labeling_behaviors[6] = {
	"uses xattr",
	"uses transition SIDs",
	"uses task SIDs",
	"uses genfs_contexts",
	"not configured for labeling",
	"uses mountpoint labeling",
};

static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dentry);

static inline int inode_doinit(struct inode *inode)
{
	return inode_doinit_with_dentry(inode, NULL);
}

enum {
351
	Opt_error = -1,
L
Linus Torvalds 已提交
352 353
	Opt_context = 1,
	Opt_fscontext = 2,
354 355
	Opt_defcontext = 3,
	Opt_rootcontext = 4,
L
Linus Torvalds 已提交
356 357
};

358
static const match_table_t tokens = {
359 360 361 362
	{Opt_context, CONTEXT_STR "%s"},
	{Opt_fscontext, FSCONTEXT_STR "%s"},
	{Opt_defcontext, DEFCONTEXT_STR "%s"},
	{Opt_rootcontext, ROOTCONTEXT_STR "%s"},
363
	{Opt_error, NULL},
L
Linus Torvalds 已提交
364 365 366 367
};

#define SEL_MOUNT_FAIL_MSG "SELinux:  duplicate or incompatible mount options\n"

368 369
static int may_context_mount_sb_relabel(u32 sid,
			struct superblock_security_struct *sbsec,
370
			const struct cred *cred)
371
{
372
	const struct task_security_struct *tsec = cred->security;
373 374 375 376 377 378 379 380 381 382 383 384
	int rc;

	rc = avc_has_perm(tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM,
			  FILESYSTEM__RELABELFROM, NULL);
	if (rc)
		return rc;

	rc = avc_has_perm(tsec->sid, sid, SECCLASS_FILESYSTEM,
			  FILESYSTEM__RELABELTO, NULL);
	return rc;
}

385 386
static int may_context_mount_inode_relabel(u32 sid,
			struct superblock_security_struct *sbsec,
387
			const struct cred *cred)
388
{
389
	const struct task_security_struct *tsec = cred->security;
390 391 392 393 394 395 396 397 398 399 400
	int rc;
	rc = avc_has_perm(tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM,
			  FILESYSTEM__RELABELFROM, NULL);
	if (rc)
		return rc;

	rc = avc_has_perm(sid, sbsec->sid, SECCLASS_FILESYSTEM,
			  FILESYSTEM__ASSOCIATE, NULL);
	return rc;
}

401
static int sb_finish_set_opts(struct super_block *sb)
L
Linus Torvalds 已提交
402 403
{
	struct superblock_security_struct *sbsec = sb->s_security;
404 405 406
	struct dentry *root = sb->s_root;
	struct inode *root_inode = root->d_inode;
	int rc = 0;
L
Linus Torvalds 已提交
407

408 409 410 411 412 413 414 415 416 417 418 419 420 421 422 423 424 425 426 427 428 429 430 431 432
	if (sbsec->behavior == SECURITY_FS_USE_XATTR) {
		/* Make sure that the xattr handler exists and that no
		   error other than -ENODATA is returned by getxattr on
		   the root directory.  -ENODATA is ok, as this may be
		   the first boot of the SELinux kernel before we have
		   assigned xattr values to the filesystem. */
		if (!root_inode->i_op->getxattr) {
			printk(KERN_WARNING "SELinux: (dev %s, type %s) has no "
			       "xattr support\n", sb->s_id, sb->s_type->name);
			rc = -EOPNOTSUPP;
			goto out;
		}
		rc = root_inode->i_op->getxattr(root, XATTR_NAME_SELINUX, NULL, 0);
		if (rc < 0 && rc != -ENODATA) {
			if (rc == -EOPNOTSUPP)
				printk(KERN_WARNING "SELinux: (dev %s, type "
				       "%s) has no security xattr handler\n",
				       sb->s_id, sb->s_type->name);
			else
				printk(KERN_WARNING "SELinux: (dev %s, type "
				       "%s) getxattr errno %d\n", sb->s_id,
				       sb->s_type->name, -rc);
			goto out;
		}
	}
L
Linus Torvalds 已提交
433

434
	sbsec->initialized = 1;
L
Linus Torvalds 已提交
435

436 437 438 439 440 441 442
	if (sbsec->behavior > ARRAY_SIZE(labeling_behaviors))
		printk(KERN_ERR "SELinux: initialized (dev %s, type %s), unknown behavior\n",
		       sb->s_id, sb->s_type->name);
	else
		printk(KERN_DEBUG "SELinux: initialized (dev %s, type %s), %s\n",
		       sb->s_id, sb->s_type->name,
		       labeling_behaviors[sbsec->behavior-1]);
L
Linus Torvalds 已提交
443

444 445
	/* Initialize the root inode. */
	rc = inode_doinit_with_dentry(root_inode, root);
L
Linus Torvalds 已提交
446

447 448 449 450 451 452 453 454 455 456 457 458 459 460 461 462 463 464 465 466 467 468 469 470 471 472
	/* Initialize any other inodes associated with the superblock, e.g.
	   inodes created prior to initial policy load or inodes created
	   during get_sb by a pseudo filesystem that directly
	   populates itself. */
	spin_lock(&sbsec->isec_lock);
next_inode:
	if (!list_empty(&sbsec->isec_head)) {
		struct inode_security_struct *isec =
				list_entry(sbsec->isec_head.next,
					   struct inode_security_struct, list);
		struct inode *inode = isec->inode;
		spin_unlock(&sbsec->isec_lock);
		inode = igrab(inode);
		if (inode) {
			if (!IS_PRIVATE(inode))
				inode_doinit(inode);
			iput(inode);
		}
		spin_lock(&sbsec->isec_lock);
		list_del_init(&isec->list);
		goto next_inode;
	}
	spin_unlock(&sbsec->isec_lock);
out:
	return rc;
}
L
Linus Torvalds 已提交
473

474 475 476 477 478 479
/*
 * This function should allow an FS to ask what it's mount security
 * options were so it can use those later for submounts, displaying
 * mount options, or whatever.
 */
static int selinux_get_mnt_opts(const struct super_block *sb,
480
				struct security_mnt_opts *opts)
481 482 483 484 485 486
{
	int rc = 0, i;
	struct superblock_security_struct *sbsec = sb->s_security;
	char *context = NULL;
	u32 len;
	char tmp;
L
Linus Torvalds 已提交
487

488
	security_init_mnt_opts(opts);
L
Linus Torvalds 已提交
489

490 491
	if (!sbsec->initialized)
		return -EINVAL;
L
Linus Torvalds 已提交
492

493 494
	if (!ss_initialized)
		return -EINVAL;
L
Linus Torvalds 已提交
495

496 497 498 499 500 501 502 503
	/*
	 * if we ever use sbsec flags for anything other than tracking mount
	 * settings this is going to need a mask
	 */
	tmp = sbsec->flags;
	/* count the number of mount options for this sb */
	for (i = 0; i < 8; i++) {
		if (tmp & 0x01)
504
			opts->num_mnt_opts++;
505 506
		tmp >>= 1;
	}
L
Linus Torvalds 已提交
507

508 509
	opts->mnt_opts = kcalloc(opts->num_mnt_opts, sizeof(char *), GFP_ATOMIC);
	if (!opts->mnt_opts) {
510 511 512
		rc = -ENOMEM;
		goto out_free;
	}
L
Linus Torvalds 已提交
513

514 515
	opts->mnt_opts_flags = kcalloc(opts->num_mnt_opts, sizeof(int), GFP_ATOMIC);
	if (!opts->mnt_opts_flags) {
516 517 518
		rc = -ENOMEM;
		goto out_free;
	}
L
Linus Torvalds 已提交
519

520 521 522 523 524
	i = 0;
	if (sbsec->flags & FSCONTEXT_MNT) {
		rc = security_sid_to_context(sbsec->sid, &context, &len);
		if (rc)
			goto out_free;
525 526
		opts->mnt_opts[i] = context;
		opts->mnt_opts_flags[i++] = FSCONTEXT_MNT;
527 528 529 530 531
	}
	if (sbsec->flags & CONTEXT_MNT) {
		rc = security_sid_to_context(sbsec->mntpoint_sid, &context, &len);
		if (rc)
			goto out_free;
532 533
		opts->mnt_opts[i] = context;
		opts->mnt_opts_flags[i++] = CONTEXT_MNT;
534 535 536 537 538
	}
	if (sbsec->flags & DEFCONTEXT_MNT) {
		rc = security_sid_to_context(sbsec->def_sid, &context, &len);
		if (rc)
			goto out_free;
539 540
		opts->mnt_opts[i] = context;
		opts->mnt_opts_flags[i++] = DEFCONTEXT_MNT;
541 542 543 544
	}
	if (sbsec->flags & ROOTCONTEXT_MNT) {
		struct inode *root = sbsec->sb->s_root->d_inode;
		struct inode_security_struct *isec = root->i_security;
545

546 547 548
		rc = security_sid_to_context(isec->sid, &context, &len);
		if (rc)
			goto out_free;
549 550
		opts->mnt_opts[i] = context;
		opts->mnt_opts_flags[i++] = ROOTCONTEXT_MNT;
551
	}
L
Linus Torvalds 已提交
552

553
	BUG_ON(i != opts->num_mnt_opts);
L
Linus Torvalds 已提交
554

555 556 557
	return 0;

out_free:
558
	security_free_mnt_opts(opts);
559 560
	return rc;
}
L
Linus Torvalds 已提交
561

562 563 564 565 566 567 568 569 570 571 572 573 574 575 576 577 578
static int bad_option(struct superblock_security_struct *sbsec, char flag,
		      u32 old_sid, u32 new_sid)
{
	/* check if the old mount command had the same options */
	if (sbsec->initialized)
		if (!(sbsec->flags & flag) ||
		    (old_sid != new_sid))
			return 1;

	/* check if we were passed the same options twice,
	 * aka someone passed context=a,context=b
	 */
	if (!sbsec->initialized)
		if (sbsec->flags & flag)
			return 1;
	return 0;
}
579

580 581 582 583
/*
 * Allow filesystems with binary mount data to explicitly set mount point
 * labeling information.
 */
584 585
static int selinux_set_mnt_opts(struct super_block *sb,
				struct security_mnt_opts *opts)
586
{
587
	const struct cred *cred = current_cred();
588 589 590
	int rc = 0, i;
	struct superblock_security_struct *sbsec = sb->s_security;
	const char *name = sb->s_type->name;
591 592
	struct inode *inode = sbsec->sb->s_root->d_inode;
	struct inode_security_struct *root_isec = inode->i_security;
593 594
	u32 fscontext_sid = 0, context_sid = 0, rootcontext_sid = 0;
	u32 defcontext_sid = 0;
595 596 597
	char **mount_options = opts->mnt_opts;
	int *flags = opts->mnt_opts_flags;
	int num_opts = opts->num_mnt_opts;
598 599 600 601 602 603 604 605 606 607 608 609 610 611 612

	mutex_lock(&sbsec->lock);

	if (!ss_initialized) {
		if (!num_opts) {
			/* Defer initialization until selinux_complete_init,
			   after the initial policy is loaded and the security
			   server is ready to handle calls. */
			spin_lock(&sb_security_lock);
			if (list_empty(&sbsec->list))
				list_add(&sbsec->list, &superblock_security_head);
			spin_unlock(&sb_security_lock);
			goto out;
		}
		rc = -EINVAL;
E
Eric Paris 已提交
613 614
		printk(KERN_WARNING "SELinux: Unable to set superblock options "
			"before the security server is initialized\n");
L
Linus Torvalds 已提交
615
		goto out;
616
	}
L
Linus Torvalds 已提交
617

618 619 620 621 622 623 624 625 626 627 628 629 630
	/*
	 * Binary mount data FS will come through this function twice.  Once
	 * from an explicit call and once from the generic calls from the vfs.
	 * Since the generic VFS calls will not contain any security mount data
	 * we need to skip the double mount verification.
	 *
	 * This does open a hole in which we will not notice if the first
	 * mount using this sb set explict options and a second mount using
	 * this sb does not set any security options.  (The first options
	 * will be used for both mounts)
	 */
	if (sbsec->initialized && (sb->s_type->fs_flags & FS_BINARY_MOUNTDATA)
	    && (num_opts == 0))
631
		goto out;
632

633 634 635 636 637 638 639 640 641
	/*
	 * parse the mount options, check if they are valid sids.
	 * also check if someone is trying to mount the same sb more
	 * than once with different security options.
	 */
	for (i = 0; i < num_opts; i++) {
		u32 sid;
		rc = security_context_to_sid(mount_options[i],
					     strlen(mount_options[i]), &sid);
L
Linus Torvalds 已提交
642 643 644
		if (rc) {
			printk(KERN_WARNING "SELinux: security_context_to_sid"
			       "(%s) failed for (dev %s, type %s) errno=%d\n",
645 646 647 648 649 650 651 652 653 654 655 656 657 658 659 660 661 662 663 664 665 666 667 668 669 670 671 672 673 674 675 676 677 678 679 680 681 682 683 684 685 686 687 688 689
			       mount_options[i], sb->s_id, name, rc);
			goto out;
		}
		switch (flags[i]) {
		case FSCONTEXT_MNT:
			fscontext_sid = sid;

			if (bad_option(sbsec, FSCONTEXT_MNT, sbsec->sid,
					fscontext_sid))
				goto out_double_mount;

			sbsec->flags |= FSCONTEXT_MNT;
			break;
		case CONTEXT_MNT:
			context_sid = sid;

			if (bad_option(sbsec, CONTEXT_MNT, sbsec->mntpoint_sid,
					context_sid))
				goto out_double_mount;

			sbsec->flags |= CONTEXT_MNT;
			break;
		case ROOTCONTEXT_MNT:
			rootcontext_sid = sid;

			if (bad_option(sbsec, ROOTCONTEXT_MNT, root_isec->sid,
					rootcontext_sid))
				goto out_double_mount;

			sbsec->flags |= ROOTCONTEXT_MNT;

			break;
		case DEFCONTEXT_MNT:
			defcontext_sid = sid;

			if (bad_option(sbsec, DEFCONTEXT_MNT, sbsec->def_sid,
					defcontext_sid))
				goto out_double_mount;

			sbsec->flags |= DEFCONTEXT_MNT;

			break;
		default:
			rc = -EINVAL;
			goto out;
L
Linus Torvalds 已提交
690
		}
691 692 693 694 695 696 697 698 699 700
	}

	if (sbsec->initialized) {
		/* previously mounted with options, but not on this attempt? */
		if (sbsec->flags && !num_opts)
			goto out_double_mount;
		rc = 0;
		goto out;
	}

701
	if (strcmp(sb->s_type->name, "proc") == 0)
702 703 704
		sbsec->proc = 1;

	/* Determine the labeling behavior to use for this filesystem type. */
705
	rc = security_fs_use(sbsec->proc ? "proc" : sb->s_type->name, &sbsec->behavior, &sbsec->sid);
706 707
	if (rc) {
		printk(KERN_WARNING "%s: security_fs_use(%s) returned %d\n",
708
		       __func__, sb->s_type->name, rc);
709 710
		goto out;
	}
L
Linus Torvalds 已提交
711

712 713
	/* sets the context of the superblock for the fs being mounted. */
	if (fscontext_sid) {
714
		rc = may_context_mount_sb_relabel(fscontext_sid, sbsec, cred);
L
Linus Torvalds 已提交
715
		if (rc)
716
			goto out;
L
Linus Torvalds 已提交
717

718
		sbsec->sid = fscontext_sid;
719 720 721 722 723 724 725
	}

	/*
	 * Switch to using mount point labeling behavior.
	 * sets the label used on all file below the mountpoint, and will set
	 * the superblock context if not already set.
	 */
726 727
	if (context_sid) {
		if (!fscontext_sid) {
728 729
			rc = may_context_mount_sb_relabel(context_sid, sbsec,
							  cred);
730
			if (rc)
731 732
				goto out;
			sbsec->sid = context_sid;
733
		} else {
734 735
			rc = may_context_mount_inode_relabel(context_sid, sbsec,
							     cred);
736
			if (rc)
737
				goto out;
738
		}
739 740
		if (!rootcontext_sid)
			rootcontext_sid = context_sid;
L
Linus Torvalds 已提交
741

742
		sbsec->mntpoint_sid = context_sid;
743
		sbsec->behavior = SECURITY_FS_USE_MNTPOINT;
L
Linus Torvalds 已提交
744 745
	}

746
	if (rootcontext_sid) {
747 748
		rc = may_context_mount_inode_relabel(rootcontext_sid, sbsec,
						     cred);
749
		if (rc)
750
			goto out;
751

752 753
		root_isec->sid = rootcontext_sid;
		root_isec->initialized = 1;
754 755
	}

756 757 758 759 760 761
	if (defcontext_sid) {
		if (sbsec->behavior != SECURITY_FS_USE_XATTR) {
			rc = -EINVAL;
			printk(KERN_WARNING "SELinux: defcontext option is "
			       "invalid for this filesystem type\n");
			goto out;
L
Linus Torvalds 已提交
762 763
		}

764 765
		if (defcontext_sid != sbsec->def_sid) {
			rc = may_context_mount_inode_relabel(defcontext_sid,
766
							     sbsec, cred);
767 768 769
			if (rc)
				goto out;
		}
L
Linus Torvalds 已提交
770

771
		sbsec->def_sid = defcontext_sid;
L
Linus Torvalds 已提交
772 773
	}

774
	rc = sb_finish_set_opts(sb);
L
Linus Torvalds 已提交
775
out:
776
	mutex_unlock(&sbsec->lock);
L
Linus Torvalds 已提交
777
	return rc;
778 779 780 781 782
out_double_mount:
	rc = -EINVAL;
	printk(KERN_WARNING "SELinux: mount invalid.  Same superblock, different "
	       "security settings for (dev %s, type %s)\n", sb->s_id, name);
	goto out;
L
Linus Torvalds 已提交
783 784
}

785 786
static void selinux_sb_clone_mnt_opts(const struct super_block *oldsb,
					struct super_block *newsb)
L
Linus Torvalds 已提交
787
{
788 789
	const struct superblock_security_struct *oldsbsec = oldsb->s_security;
	struct superblock_security_struct *newsbsec = newsb->s_security;
L
Linus Torvalds 已提交
790

791 792 793
	int set_fscontext =	(oldsbsec->flags & FSCONTEXT_MNT);
	int set_context =	(oldsbsec->flags & CONTEXT_MNT);
	int set_rootcontext =	(oldsbsec->flags & ROOTCONTEXT_MNT);
L
Linus Torvalds 已提交
794

795 796 797 798 799 800 801 802 803 804 805 806
	/*
	 * if the parent was able to be mounted it clearly had no special lsm
	 * mount options.  thus we can safely put this sb on the list and deal
	 * with it later
	 */
	if (!ss_initialized) {
		spin_lock(&sb_security_lock);
		if (list_empty(&newsbsec->list))
			list_add(&newsbsec->list, &superblock_security_head);
		spin_unlock(&sb_security_lock);
		return;
	}
807 808 809 810

	/* how can we clone if the old one wasn't set up?? */
	BUG_ON(!oldsbsec->initialized);

811 812 813 814
	/* if fs is reusing a sb, just let its options stand... */
	if (newsbsec->initialized)
		return;

815 816 817 818 819 820 821 822 823 824 825 826 827 828 829 830 831 832 833
	mutex_lock(&newsbsec->lock);

	newsbsec->flags = oldsbsec->flags;

	newsbsec->sid = oldsbsec->sid;
	newsbsec->def_sid = oldsbsec->def_sid;
	newsbsec->behavior = oldsbsec->behavior;

	if (set_context) {
		u32 sid = oldsbsec->mntpoint_sid;

		if (!set_fscontext)
			newsbsec->sid = sid;
		if (!set_rootcontext) {
			struct inode *newinode = newsb->s_root->d_inode;
			struct inode_security_struct *newisec = newinode->i_security;
			newisec->sid = sid;
		}
		newsbsec->mntpoint_sid = sid;
L
Linus Torvalds 已提交
834
	}
835 836 837 838 839
	if (set_rootcontext) {
		const struct inode *oldinode = oldsb->s_root->d_inode;
		const struct inode_security_struct *oldisec = oldinode->i_security;
		struct inode *newinode = newsb->s_root->d_inode;
		struct inode_security_struct *newisec = newinode->i_security;
L
Linus Torvalds 已提交
840

841
		newisec->sid = oldisec->sid;
L
Linus Torvalds 已提交
842 843
	}

844 845 846 847
	sb_finish_set_opts(newsb);
	mutex_unlock(&newsbsec->lock);
}

848 849
static int selinux_parse_opts_str(char *options,
				  struct security_mnt_opts *opts)
850
{
851
	char *p;
852 853
	char *context = NULL, *defcontext = NULL;
	char *fscontext = NULL, *rootcontext = NULL;
854
	int rc, num_mnt_opts = 0;
L
Linus Torvalds 已提交
855

856
	opts->num_mnt_opts = 0;
L
Linus Torvalds 已提交
857

858 859 860 861
	/* Standard string-based options. */
	while ((p = strsep(&options, "|")) != NULL) {
		int token;
		substring_t args[MAX_OPT_ARGS];
L
Linus Torvalds 已提交
862

863 864
		if (!*p)
			continue;
L
Linus Torvalds 已提交
865

866
		token = match_token(p, tokens, args);
L
Linus Torvalds 已提交
867

868 869 870 871 872 873 874 875 876 877 878 879 880 881 882 883 884 885 886 887 888 889 890 891 892 893 894 895 896 897 898 899 900 901 902 903 904 905 906 907 908 909 910 911 912 913 914 915 916 917 918 919 920 921 922 923 924
		switch (token) {
		case Opt_context:
			if (context || defcontext) {
				rc = -EINVAL;
				printk(KERN_WARNING SEL_MOUNT_FAIL_MSG);
				goto out_err;
			}
			context = match_strdup(&args[0]);
			if (!context) {
				rc = -ENOMEM;
				goto out_err;
			}
			break;

		case Opt_fscontext:
			if (fscontext) {
				rc = -EINVAL;
				printk(KERN_WARNING SEL_MOUNT_FAIL_MSG);
				goto out_err;
			}
			fscontext = match_strdup(&args[0]);
			if (!fscontext) {
				rc = -ENOMEM;
				goto out_err;
			}
			break;

		case Opt_rootcontext:
			if (rootcontext) {
				rc = -EINVAL;
				printk(KERN_WARNING SEL_MOUNT_FAIL_MSG);
				goto out_err;
			}
			rootcontext = match_strdup(&args[0]);
			if (!rootcontext) {
				rc = -ENOMEM;
				goto out_err;
			}
			break;

		case Opt_defcontext:
			if (context || defcontext) {
				rc = -EINVAL;
				printk(KERN_WARNING SEL_MOUNT_FAIL_MSG);
				goto out_err;
			}
			defcontext = match_strdup(&args[0]);
			if (!defcontext) {
				rc = -ENOMEM;
				goto out_err;
			}
			break;

		default:
			rc = -EINVAL;
			printk(KERN_WARNING "SELinux:  unknown mount option\n");
			goto out_err;
L
Linus Torvalds 已提交
925 926 927

		}
	}
928

929 930 931 932 933 934 935 936 937 938 939
	rc = -ENOMEM;
	opts->mnt_opts = kcalloc(NUM_SEL_MNT_OPTS, sizeof(char *), GFP_ATOMIC);
	if (!opts->mnt_opts)
		goto out_err;

	opts->mnt_opts_flags = kcalloc(NUM_SEL_MNT_OPTS, sizeof(int), GFP_ATOMIC);
	if (!opts->mnt_opts_flags) {
		kfree(opts->mnt_opts);
		goto out_err;
	}

940
	if (fscontext) {
941 942
		opts->mnt_opts[num_mnt_opts] = fscontext;
		opts->mnt_opts_flags[num_mnt_opts++] = FSCONTEXT_MNT;
943 944
	}
	if (context) {
945 946
		opts->mnt_opts[num_mnt_opts] = context;
		opts->mnt_opts_flags[num_mnt_opts++] = CONTEXT_MNT;
947 948
	}
	if (rootcontext) {
949 950
		opts->mnt_opts[num_mnt_opts] = rootcontext;
		opts->mnt_opts_flags[num_mnt_opts++] = ROOTCONTEXT_MNT;
951 952
	}
	if (defcontext) {
953 954
		opts->mnt_opts[num_mnt_opts] = defcontext;
		opts->mnt_opts_flags[num_mnt_opts++] = DEFCONTEXT_MNT;
955 956
	}

957 958 959
	opts->num_mnt_opts = num_mnt_opts;
	return 0;

960 961 962 963 964
out_err:
	kfree(context);
	kfree(defcontext);
	kfree(fscontext);
	kfree(rootcontext);
L
Linus Torvalds 已提交
965 966
	return rc;
}
967 968 969 970 971 972 973 974 975 976 977 978 979 980 981 982 983 984 985 986 987 988 989 990 991 992 993
/*
 * string mount options parsing and call set the sbsec
 */
static int superblock_doinit(struct super_block *sb, void *data)
{
	int rc = 0;
	char *options = data;
	struct security_mnt_opts opts;

	security_init_mnt_opts(&opts);

	if (!data)
		goto out;

	BUG_ON(sb->s_type->fs_flags & FS_BINARY_MOUNTDATA);

	rc = selinux_parse_opts_str(options, &opts);
	if (rc)
		goto out_err;

out:
	rc = selinux_set_mnt_opts(sb, &opts);

out_err:
	security_free_mnt_opts(&opts);
	return rc;
}
L
Linus Torvalds 已提交
994

A
Adrian Bunk 已提交
995 996
static void selinux_write_opts(struct seq_file *m,
			       struct security_mnt_opts *opts)
997 998 999 1000 1001 1002 1003 1004 1005 1006 1007 1008 1009 1010 1011 1012 1013 1014 1015 1016 1017 1018 1019 1020 1021 1022 1023 1024 1025 1026 1027 1028 1029 1030 1031 1032 1033 1034 1035 1036
{
	int i;
	char *prefix;

	for (i = 0; i < opts->num_mnt_opts; i++) {
		char *has_comma = strchr(opts->mnt_opts[i], ',');

		switch (opts->mnt_opts_flags[i]) {
		case CONTEXT_MNT:
			prefix = CONTEXT_STR;
			break;
		case FSCONTEXT_MNT:
			prefix = FSCONTEXT_STR;
			break;
		case ROOTCONTEXT_MNT:
			prefix = ROOTCONTEXT_STR;
			break;
		case DEFCONTEXT_MNT:
			prefix = DEFCONTEXT_STR;
			break;
		default:
			BUG();
		};
		/* we need a comma before each option */
		seq_putc(m, ',');
		seq_puts(m, prefix);
		if (has_comma)
			seq_putc(m, '\"');
		seq_puts(m, opts->mnt_opts[i]);
		if (has_comma)
			seq_putc(m, '\"');
	}
}

static int selinux_sb_show_options(struct seq_file *m, struct super_block *sb)
{
	struct security_mnt_opts opts;
	int rc;

	rc = selinux_get_mnt_opts(sb, &opts);
1037 1038 1039 1040
	if (rc) {
		/* before policy load we may get EINVAL, don't show anything */
		if (rc == -EINVAL)
			rc = 0;
1041
		return rc;
1042
	}
1043 1044 1045 1046 1047 1048 1049 1050

	selinux_write_opts(m, &opts);

	security_free_mnt_opts(&opts);

	return rc;
}

L
Linus Torvalds 已提交
1051 1052 1053 1054 1055 1056 1057 1058 1059 1060 1061 1062 1063 1064 1065 1066 1067 1068 1069 1070 1071 1072 1073
static inline u16 inode_mode_to_security_class(umode_t mode)
{
	switch (mode & S_IFMT) {
	case S_IFSOCK:
		return SECCLASS_SOCK_FILE;
	case S_IFLNK:
		return SECCLASS_LNK_FILE;
	case S_IFREG:
		return SECCLASS_FILE;
	case S_IFBLK:
		return SECCLASS_BLK_FILE;
	case S_IFDIR:
		return SECCLASS_DIR;
	case S_IFCHR:
		return SECCLASS_CHR_FILE;
	case S_IFIFO:
		return SECCLASS_FIFO_FILE;

	}

	return SECCLASS_FILE;
}

1074 1075 1076 1077 1078 1079 1080 1081 1082 1083
static inline int default_protocol_stream(int protocol)
{
	return (protocol == IPPROTO_IP || protocol == IPPROTO_TCP);
}

static inline int default_protocol_dgram(int protocol)
{
	return (protocol == IPPROTO_IP || protocol == IPPROTO_UDP);
}

L
Linus Torvalds 已提交
1084 1085 1086 1087 1088 1089 1090 1091 1092 1093 1094 1095 1096 1097 1098 1099
static inline u16 socket_type_to_security_class(int family, int type, int protocol)
{
	switch (family) {
	case PF_UNIX:
		switch (type) {
		case SOCK_STREAM:
		case SOCK_SEQPACKET:
			return SECCLASS_UNIX_STREAM_SOCKET;
		case SOCK_DGRAM:
			return SECCLASS_UNIX_DGRAM_SOCKET;
		}
		break;
	case PF_INET:
	case PF_INET6:
		switch (type) {
		case SOCK_STREAM:
1100 1101 1102 1103
			if (default_protocol_stream(protocol))
				return SECCLASS_TCP_SOCKET;
			else
				return SECCLASS_RAWIP_SOCKET;
L
Linus Torvalds 已提交
1104
		case SOCK_DGRAM:
1105 1106 1107 1108
			if (default_protocol_dgram(protocol))
				return SECCLASS_UDP_SOCKET;
			else
				return SECCLASS_RAWIP_SOCKET;
J
James Morris 已提交
1109 1110
		case SOCK_DCCP:
			return SECCLASS_DCCP_SOCKET;
1111
		default:
L
Linus Torvalds 已提交
1112 1113 1114 1115 1116 1117 1118 1119 1120
			return SECCLASS_RAWIP_SOCKET;
		}
		break;
	case PF_NETLINK:
		switch (protocol) {
		case NETLINK_ROUTE:
			return SECCLASS_NETLINK_ROUTE_SOCKET;
		case NETLINK_FIREWALL:
			return SECCLASS_NETLINK_FIREWALL_SOCKET;
1121
		case NETLINK_INET_DIAG:
L
Linus Torvalds 已提交
1122 1123 1124 1125 1126 1127 1128 1129 1130 1131 1132 1133 1134
			return SECCLASS_NETLINK_TCPDIAG_SOCKET;
		case NETLINK_NFLOG:
			return SECCLASS_NETLINK_NFLOG_SOCKET;
		case NETLINK_XFRM:
			return SECCLASS_NETLINK_XFRM_SOCKET;
		case NETLINK_SELINUX:
			return SECCLASS_NETLINK_SELINUX_SOCKET;
		case NETLINK_AUDIT:
			return SECCLASS_NETLINK_AUDIT_SOCKET;
		case NETLINK_IP6_FW:
			return SECCLASS_NETLINK_IP6FW_SOCKET;
		case NETLINK_DNRTMSG:
			return SECCLASS_NETLINK_DNRT_SOCKET;
1135 1136
		case NETLINK_KOBJECT_UEVENT:
			return SECCLASS_NETLINK_KOBJECT_UEVENT_SOCKET;
L
Linus Torvalds 已提交
1137 1138 1139 1140 1141 1142 1143
		default:
			return SECCLASS_NETLINK_SOCKET;
		}
	case PF_PACKET:
		return SECCLASS_PACKET_SOCKET;
	case PF_KEY:
		return SECCLASS_KEY_SOCKET;
1144 1145
	case PF_APPLETALK:
		return SECCLASS_APPLETALK_SOCKET;
L
Linus Torvalds 已提交
1146 1147 1148 1149 1150 1151 1152 1153 1154 1155 1156 1157 1158
	}

	return SECCLASS_SOCKET;
}

#ifdef CONFIG_PROC_FS
static int selinux_proc_get_sid(struct proc_dir_entry *de,
				u16 tclass,
				u32 *sid)
{
	int buflen, rc;
	char *buffer, *path, *end;

1159
	buffer = (char *)__get_free_page(GFP_KERNEL);
L
Linus Torvalds 已提交
1160 1161 1162 1163 1164 1165 1166 1167 1168 1169 1170 1171 1172 1173 1174 1175 1176 1177 1178 1179 1180 1181 1182 1183 1184 1185 1186 1187 1188 1189 1190 1191 1192 1193 1194 1195 1196 1197 1198 1199 1200 1201 1202 1203 1204 1205 1206
	if (!buffer)
		return -ENOMEM;

	buflen = PAGE_SIZE;
	end = buffer+buflen;
	*--end = '\0';
	buflen--;
	path = end-1;
	*path = '/';
	while (de && de != de->parent) {
		buflen -= de->namelen + 1;
		if (buflen < 0)
			break;
		end -= de->namelen;
		memcpy(end, de->name, de->namelen);
		*--end = '/';
		path = end;
		de = de->parent;
	}
	rc = security_genfs_sid("proc", path, tclass, sid);
	free_page((unsigned long)buffer);
	return rc;
}
#else
static int selinux_proc_get_sid(struct proc_dir_entry *de,
				u16 tclass,
				u32 *sid)
{
	return -EINVAL;
}
#endif

/* The inode's security attributes must be initialized before first use. */
static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dentry)
{
	struct superblock_security_struct *sbsec = NULL;
	struct inode_security_struct *isec = inode->i_security;
	u32 sid;
	struct dentry *dentry;
#define INITCONTEXTLEN 255
	char *context = NULL;
	unsigned len = 0;
	int rc = 0;

	if (isec->initialized)
		goto out;

1207
	mutex_lock(&isec->lock);
L
Linus Torvalds 已提交
1208
	if (isec->initialized)
1209
		goto out_unlock;
L
Linus Torvalds 已提交
1210 1211 1212 1213 1214 1215 1216 1217 1218 1219

	sbsec = inode->i_sb->s_security;
	if (!sbsec->initialized) {
		/* Defer initialization until selinux_complete_init,
		   after the initial policy is loaded and the security
		   server is ready to handle calls. */
		spin_lock(&sbsec->isec_lock);
		if (list_empty(&isec->list))
			list_add(&isec->list, &sbsec->isec_head);
		spin_unlock(&sbsec->isec_lock);
1220
		goto out_unlock;
L
Linus Torvalds 已提交
1221 1222 1223 1224 1225 1226 1227 1228 1229 1230 1231 1232 1233 1234 1235 1236 1237 1238 1239
	}

	switch (sbsec->behavior) {
	case SECURITY_FS_USE_XATTR:
		if (!inode->i_op->getxattr) {
			isec->sid = sbsec->def_sid;
			break;
		}

		/* Need a dentry, since the xattr API requires one.
		   Life would be simpler if we could just pass the inode. */
		if (opt_dentry) {
			/* Called from d_instantiate or d_splice_alias. */
			dentry = dget(opt_dentry);
		} else {
			/* Called from selinux_complete_init, try to find a dentry. */
			dentry = d_find_alias(inode);
		}
		if (!dentry) {
E
Eric Paris 已提交
1240
			printk(KERN_WARNING "SELinux: %s:  no dentry for dev=%s "
1241
			       "ino=%ld\n", __func__, inode->i_sb->s_id,
L
Linus Torvalds 已提交
1242
			       inode->i_ino);
1243
			goto out_unlock;
L
Linus Torvalds 已提交
1244 1245 1246
		}

		len = INITCONTEXTLEN;
1247
		context = kmalloc(len, GFP_NOFS);
L
Linus Torvalds 已提交
1248 1249 1250
		if (!context) {
			rc = -ENOMEM;
			dput(dentry);
1251
			goto out_unlock;
L
Linus Torvalds 已提交
1252 1253 1254 1255 1256 1257 1258 1259 1260
		}
		rc = inode->i_op->getxattr(dentry, XATTR_NAME_SELINUX,
					   context, len);
		if (rc == -ERANGE) {
			/* Need a larger buffer.  Query for the right size. */
			rc = inode->i_op->getxattr(dentry, XATTR_NAME_SELINUX,
						   NULL, 0);
			if (rc < 0) {
				dput(dentry);
1261
				goto out_unlock;
L
Linus Torvalds 已提交
1262 1263 1264
			}
			kfree(context);
			len = rc;
1265
			context = kmalloc(len, GFP_NOFS);
L
Linus Torvalds 已提交
1266 1267 1268
			if (!context) {
				rc = -ENOMEM;
				dput(dentry);
1269
				goto out_unlock;
L
Linus Torvalds 已提交
1270 1271 1272 1273 1274 1275 1276 1277
			}
			rc = inode->i_op->getxattr(dentry,
						   XATTR_NAME_SELINUX,
						   context, len);
		}
		dput(dentry);
		if (rc < 0) {
			if (rc != -ENODATA) {
E
Eric Paris 已提交
1278
				printk(KERN_WARNING "SELinux: %s:  getxattr returned "
1279
				       "%d for dev=%s ino=%ld\n", __func__,
L
Linus Torvalds 已提交
1280 1281
				       -rc, inode->i_sb->s_id, inode->i_ino);
				kfree(context);
1282
				goto out_unlock;
L
Linus Torvalds 已提交
1283 1284 1285 1286 1287
			}
			/* Map ENODATA to the default file SID */
			sid = sbsec->def_sid;
			rc = 0;
		} else {
1288
			rc = security_context_to_sid_default(context, rc, &sid,
1289 1290
							     sbsec->def_sid,
							     GFP_NOFS);
L
Linus Torvalds 已提交
1291
			if (rc) {
E
Eric Paris 已提交
1292
				printk(KERN_WARNING "SELinux: %s:  context_to_sid(%s) "
L
Linus Torvalds 已提交
1293
				       "returned %d for dev=%s ino=%ld\n",
1294
				       __func__, context, -rc,
L
Linus Torvalds 已提交
1295 1296 1297 1298 1299 1300 1301 1302 1303 1304 1305 1306 1307 1308 1309 1310 1311 1312 1313 1314 1315 1316 1317 1318
				       inode->i_sb->s_id, inode->i_ino);
				kfree(context);
				/* Leave with the unlabeled SID */
				rc = 0;
				break;
			}
		}
		kfree(context);
		isec->sid = sid;
		break;
	case SECURITY_FS_USE_TASK:
		isec->sid = isec->task_sid;
		break;
	case SECURITY_FS_USE_TRANS:
		/* Default to the fs SID. */
		isec->sid = sbsec->sid;

		/* Try to obtain a transition SID. */
		isec->sclass = inode_mode_to_security_class(inode->i_mode);
		rc = security_transition_sid(isec->task_sid,
					     sbsec->sid,
					     isec->sclass,
					     &sid);
		if (rc)
1319
			goto out_unlock;
L
Linus Torvalds 已提交
1320 1321
		isec->sid = sid;
		break;
1322 1323 1324
	case SECURITY_FS_USE_MNTPOINT:
		isec->sid = sbsec->mntpoint_sid;
		break;
L
Linus Torvalds 已提交
1325
	default:
1326
		/* Default to the fs superblock SID. */
L
Linus Torvalds 已提交
1327 1328
		isec->sid = sbsec->sid;

1329
		if (sbsec->proc && !S_ISLNK(inode->i_mode)) {
L
Linus Torvalds 已提交
1330 1331 1332 1333 1334 1335 1336
			struct proc_inode *proci = PROC_I(inode);
			if (proci->pde) {
				isec->sclass = inode_mode_to_security_class(inode->i_mode);
				rc = selinux_proc_get_sid(proci->pde,
							  isec->sclass,
							  &sid);
				if (rc)
1337
					goto out_unlock;
L
Linus Torvalds 已提交
1338 1339 1340 1341 1342 1343 1344 1345
				isec->sid = sid;
			}
		}
		break;
	}

	isec->initialized = 1;

1346 1347
out_unlock:
	mutex_unlock(&isec->lock);
L
Linus Torvalds 已提交
1348 1349 1350 1351 1352 1353 1354 1355 1356 1357 1358 1359 1360 1361 1362 1363 1364 1365 1366 1367 1368 1369 1370 1371 1372 1373 1374 1375 1376 1377 1378 1379 1380
out:
	if (isec->sclass == SECCLASS_FILE)
		isec->sclass = inode_mode_to_security_class(inode->i_mode);
	return rc;
}

/* Convert a Linux signal to an access vector. */
static inline u32 signal_to_av(int sig)
{
	u32 perm = 0;

	switch (sig) {
	case SIGCHLD:
		/* Commonly granted from child to parent. */
		perm = PROCESS__SIGCHLD;
		break;
	case SIGKILL:
		/* Cannot be caught or ignored */
		perm = PROCESS__SIGKILL;
		break;
	case SIGSTOP:
		/* Cannot be caught or ignored */
		perm = PROCESS__SIGSTOP;
		break;
	default:
		/* All other signals. */
		perm = PROCESS__SIGNAL;
		break;
	}

	return perm;
}

D
David Howells 已提交
1381 1382 1383 1384 1385 1386 1387 1388 1389 1390 1391 1392 1393
/*
 * Check permission between a pair of credentials
 * fork check, ptrace check, etc.
 */
static int cred_has_perm(const struct cred *actor,
			 const struct cred *target,
			 u32 perms)
{
	u32 asid = cred_sid(actor), tsid = cred_sid(target);

	return avc_has_perm(asid, tsid, SECCLASS_PROCESS, perms, NULL);
}

1394
/*
1395
 * Check permission between a pair of tasks, e.g. signal checks,
1396 1397
 * fork check, ptrace check, etc.
 * tsk1 is the actor and tsk2 is the target
1398
 * - this uses the default subjective creds of tsk1
1399 1400 1401
 */
static int task_has_perm(const struct task_struct *tsk1,
			 const struct task_struct *tsk2,
L
Linus Torvalds 已提交
1402 1403
			 u32 perms)
{
1404 1405
	const struct task_security_struct *__tsec1, *__tsec2;
	u32 sid1, sid2;
L
Linus Torvalds 已提交
1406

1407 1408 1409 1410 1411
	rcu_read_lock();
	__tsec1 = __task_cred(tsk1)->security;	sid1 = __tsec1->sid;
	__tsec2 = __task_cred(tsk2)->security;	sid2 = __tsec2->sid;
	rcu_read_unlock();
	return avc_has_perm(sid1, sid2, SECCLASS_PROCESS, perms, NULL);
L
Linus Torvalds 已提交
1412 1413
}

1414 1415 1416 1417 1418 1419 1420 1421 1422 1423 1424 1425 1426 1427 1428 1429
/*
 * Check permission between current and another task, e.g. signal checks,
 * fork check, ptrace check, etc.
 * current is the actor and tsk2 is the target
 * - this uses current's subjective creds
 */
static int current_has_perm(const struct task_struct *tsk,
			    u32 perms)
{
	u32 sid, tsid;

	sid = current_sid();
	tsid = task_sid(tsk);
	return avc_has_perm(sid, tsid, SECCLASS_PROCESS, perms, NULL);
}

1430 1431 1432 1433
#if CAP_LAST_CAP > 63
#error Fix SELinux to handle capabilities > 63.
#endif

L
Linus Torvalds 已提交
1434 1435
/* Check whether a task is allowed to use a capability. */
static int task_has_capability(struct task_struct *tsk,
1436
			       int cap, int audit)
L
Linus Torvalds 已提交
1437 1438
{
	struct avc_audit_data ad;
1439
	struct av_decision avd;
1440
	u16 sclass;
1441
	u32 sid = task_sid(tsk);
1442
	u32 av = CAP_TO_MASK(cap);
1443
	int rc;
L
Linus Torvalds 已提交
1444

1445
	AVC_AUDIT_DATA_INIT(&ad, CAP);
L
Linus Torvalds 已提交
1446 1447 1448
	ad.tsk = tsk;
	ad.u.cap = cap;

1449 1450 1451 1452 1453 1454 1455 1456 1457 1458 1459 1460
	switch (CAP_TO_INDEX(cap)) {
	case 0:
		sclass = SECCLASS_CAPABILITY;
		break;
	case 1:
		sclass = SECCLASS_CAPABILITY2;
		break;
	default:
		printk(KERN_ERR
		       "SELinux:  out of range capability %d\n", cap);
		BUG();
	}
1461

1462
	rc = avc_has_perm_noaudit(sid, sid, sclass, av, 0, &avd);
1463
	if (audit == SECURITY_CAP_AUDIT)
1464
		avc_audit(sid, sid, sclass, av, &avd, rc, &ad);
1465
	return rc;
L
Linus Torvalds 已提交
1466 1467 1468 1469 1470 1471
}

/* Check whether a task is allowed to use a system operation. */
static int task_has_system(struct task_struct *tsk,
			   u32 perms)
{
1472
	u32 sid = task_sid(tsk);
L
Linus Torvalds 已提交
1473

1474
	return avc_has_perm(sid, SECINITSID_KERNEL,
L
Linus Torvalds 已提交
1475 1476 1477 1478 1479 1480
			    SECCLASS_SYSTEM, perms, NULL);
}

/* Check whether a task has a particular permission to an inode.
   The 'adp' parameter is optional and allows other audit
   data to be passed (e.g. the dentry). */
1481
static int inode_has_perm(const struct cred *cred,
L
Linus Torvalds 已提交
1482 1483 1484 1485 1486 1487
			  struct inode *inode,
			  u32 perms,
			  struct avc_audit_data *adp)
{
	struct inode_security_struct *isec;
	struct avc_audit_data ad;
1488
	u32 sid;
L
Linus Torvalds 已提交
1489

1490
	if (unlikely(IS_PRIVATE(inode)))
1491 1492
		return 0;

1493
	sid = cred_sid(cred);
L
Linus Torvalds 已提交
1494 1495 1496 1497 1498 1499 1500 1501
	isec = inode->i_security;

	if (!adp) {
		adp = &ad;
		AVC_AUDIT_DATA_INIT(&ad, FS);
		ad.u.fs.inode = inode;
	}

1502
	return avc_has_perm(sid, isec->sid, isec->sclass, perms, adp);
L
Linus Torvalds 已提交
1503 1504 1505 1506 1507
}

/* Same as inode_has_perm, but pass explicit audit data containing
   the dentry to help the auditing code to more easily generate the
   pathname if needed. */
1508
static inline int dentry_has_perm(const struct cred *cred,
L
Linus Torvalds 已提交
1509 1510 1511 1512 1513 1514
				  struct vfsmount *mnt,
				  struct dentry *dentry,
				  u32 av)
{
	struct inode *inode = dentry->d_inode;
	struct avc_audit_data ad;
1515

1516
	AVC_AUDIT_DATA_INIT(&ad, FS);
1517 1518
	ad.u.fs.path.mnt = mnt;
	ad.u.fs.path.dentry = dentry;
1519
	return inode_has_perm(cred, inode, av, &ad);
L
Linus Torvalds 已提交
1520 1521 1522 1523 1524 1525 1526 1527 1528 1529
}

/* Check whether a task can use an open file descriptor to
   access an inode in a given way.  Check access to the
   descriptor itself, and then use dentry_has_perm to
   check a particular permission to the file.
   Access to the descriptor is implicitly granted if it
   has the same SID as the process.  If av is zero, then
   access to the file is not checked, e.g. for cases
   where only the descriptor is affected like seek. */
1530 1531 1532
static int file_has_perm(const struct cred *cred,
			 struct file *file,
			 u32 av)
L
Linus Torvalds 已提交
1533 1534
{
	struct file_security_struct *fsec = file->f_security;
1535
	struct inode *inode = file->f_path.dentry->d_inode;
L
Linus Torvalds 已提交
1536
	struct avc_audit_data ad;
1537
	u32 sid = cred_sid(cred);
L
Linus Torvalds 已提交
1538 1539 1540
	int rc;

	AVC_AUDIT_DATA_INIT(&ad, FS);
1541
	ad.u.fs.path = file->f_path;
L
Linus Torvalds 已提交
1542

1543 1544
	if (sid != fsec->sid) {
		rc = avc_has_perm(sid, fsec->sid,
L
Linus Torvalds 已提交
1545 1546 1547 1548
				  SECCLASS_FD,
				  FD__USE,
				  &ad);
		if (rc)
1549
			goto out;
L
Linus Torvalds 已提交
1550 1551 1552
	}

	/* av is zero if only checking access to the descriptor. */
1553
	rc = 0;
L
Linus Torvalds 已提交
1554
	if (av)
1555
		rc = inode_has_perm(cred, inode, av, &ad);
L
Linus Torvalds 已提交
1556

1557 1558
out:
	return rc;
L
Linus Torvalds 已提交
1559 1560 1561 1562 1563 1564 1565
}

/* Check whether a task can create a file. */
static int may_create(struct inode *dir,
		      struct dentry *dentry,
		      u16 tclass)
{
1566 1567
	const struct cred *cred = current_cred();
	const struct task_security_struct *tsec = cred->security;
L
Linus Torvalds 已提交
1568 1569
	struct inode_security_struct *dsec;
	struct superblock_security_struct *sbsec;
1570
	u32 sid, newsid;
L
Linus Torvalds 已提交
1571 1572 1573 1574 1575 1576
	struct avc_audit_data ad;
	int rc;

	dsec = dir->i_security;
	sbsec = dir->i_sb->s_security;

1577 1578 1579
	sid = tsec->sid;
	newsid = tsec->create_sid;

L
Linus Torvalds 已提交
1580
	AVC_AUDIT_DATA_INIT(&ad, FS);
1581
	ad.u.fs.path.dentry = dentry;
L
Linus Torvalds 已提交
1582

1583
	rc = avc_has_perm(sid, dsec->sid, SECCLASS_DIR,
L
Linus Torvalds 已提交
1584 1585 1586 1587 1588
			  DIR__ADD_NAME | DIR__SEARCH,
			  &ad);
	if (rc)
		return rc;

1589 1590
	if (!newsid || sbsec->behavior == SECURITY_FS_USE_MNTPOINT) {
		rc = security_transition_sid(sid, dsec->sid, tclass, &newsid);
L
Linus Torvalds 已提交
1591 1592 1593 1594
		if (rc)
			return rc;
	}

1595
	rc = avc_has_perm(sid, newsid, tclass, FILE__CREATE, &ad);
L
Linus Torvalds 已提交
1596 1597 1598 1599 1600 1601 1602 1603
	if (rc)
		return rc;

	return avc_has_perm(newsid, sbsec->sid,
			    SECCLASS_FILESYSTEM,
			    FILESYSTEM__ASSOCIATE, &ad);
}

1604 1605 1606 1607
/* Check whether a task can create a key. */
static int may_create_key(u32 ksid,
			  struct task_struct *ctx)
{
1608
	u32 sid = task_sid(ctx);
1609

1610
	return avc_has_perm(sid, ksid, SECCLASS_KEY, KEY__CREATE, NULL);
1611 1612
}

1613 1614 1615
#define MAY_LINK	0
#define MAY_UNLINK	1
#define MAY_RMDIR	2
L
Linus Torvalds 已提交
1616 1617 1618 1619 1620 1621 1622 1623 1624

/* Check whether a task can link, unlink, or rmdir a file/directory. */
static int may_link(struct inode *dir,
		    struct dentry *dentry,
		    int kind)

{
	struct inode_security_struct *dsec, *isec;
	struct avc_audit_data ad;
1625
	u32 sid = current_sid();
L
Linus Torvalds 已提交
1626 1627 1628 1629 1630 1631 1632
	u32 av;
	int rc;

	dsec = dir->i_security;
	isec = dentry->d_inode->i_security;

	AVC_AUDIT_DATA_INIT(&ad, FS);
1633
	ad.u.fs.path.dentry = dentry;
L
Linus Torvalds 已提交
1634 1635 1636

	av = DIR__SEARCH;
	av |= (kind ? DIR__REMOVE_NAME : DIR__ADD_NAME);
1637
	rc = avc_has_perm(sid, dsec->sid, SECCLASS_DIR, av, &ad);
L
Linus Torvalds 已提交
1638 1639 1640 1641 1642 1643 1644 1645 1646 1647 1648 1649 1650 1651
	if (rc)
		return rc;

	switch (kind) {
	case MAY_LINK:
		av = FILE__LINK;
		break;
	case MAY_UNLINK:
		av = FILE__UNLINK;
		break;
	case MAY_RMDIR:
		av = DIR__RMDIR;
		break;
	default:
E
Eric Paris 已提交
1652 1653
		printk(KERN_WARNING "SELinux: %s:  unrecognized kind %d\n",
			__func__, kind);
L
Linus Torvalds 已提交
1654 1655 1656
		return 0;
	}

1657
	rc = avc_has_perm(sid, isec->sid, isec->sclass, av, &ad);
L
Linus Torvalds 已提交
1658 1659 1660 1661 1662 1663 1664 1665 1666 1667
	return rc;
}

static inline int may_rename(struct inode *old_dir,
			     struct dentry *old_dentry,
			     struct inode *new_dir,
			     struct dentry *new_dentry)
{
	struct inode_security_struct *old_dsec, *new_dsec, *old_isec, *new_isec;
	struct avc_audit_data ad;
1668
	u32 sid = current_sid();
L
Linus Torvalds 已提交
1669 1670 1671 1672 1673 1674 1675 1676 1677 1678 1679
	u32 av;
	int old_is_dir, new_is_dir;
	int rc;

	old_dsec = old_dir->i_security;
	old_isec = old_dentry->d_inode->i_security;
	old_is_dir = S_ISDIR(old_dentry->d_inode->i_mode);
	new_dsec = new_dir->i_security;

	AVC_AUDIT_DATA_INIT(&ad, FS);

1680
	ad.u.fs.path.dentry = old_dentry;
1681
	rc = avc_has_perm(sid, old_dsec->sid, SECCLASS_DIR,
L
Linus Torvalds 已提交
1682 1683 1684
			  DIR__REMOVE_NAME | DIR__SEARCH, &ad);
	if (rc)
		return rc;
1685
	rc = avc_has_perm(sid, old_isec->sid,
L
Linus Torvalds 已提交
1686 1687 1688 1689
			  old_isec->sclass, FILE__RENAME, &ad);
	if (rc)
		return rc;
	if (old_is_dir && new_dir != old_dir) {
1690
		rc = avc_has_perm(sid, old_isec->sid,
L
Linus Torvalds 已提交
1691 1692 1693 1694 1695
				  old_isec->sclass, DIR__REPARENT, &ad);
		if (rc)
			return rc;
	}

1696
	ad.u.fs.path.dentry = new_dentry;
L
Linus Torvalds 已提交
1697 1698 1699
	av = DIR__ADD_NAME | DIR__SEARCH;
	if (new_dentry->d_inode)
		av |= DIR__REMOVE_NAME;
1700
	rc = avc_has_perm(sid, new_dsec->sid, SECCLASS_DIR, av, &ad);
L
Linus Torvalds 已提交
1701 1702 1703 1704 1705
	if (rc)
		return rc;
	if (new_dentry->d_inode) {
		new_isec = new_dentry->d_inode->i_security;
		new_is_dir = S_ISDIR(new_dentry->d_inode->i_mode);
1706
		rc = avc_has_perm(sid, new_isec->sid,
L
Linus Torvalds 已提交
1707 1708 1709 1710 1711 1712 1713 1714 1715 1716
				  new_isec->sclass,
				  (new_is_dir ? DIR__RMDIR : FILE__UNLINK), &ad);
		if (rc)
			return rc;
	}

	return 0;
}

/* Check whether a task can perform a filesystem operation. */
1717
static int superblock_has_perm(const struct cred *cred,
L
Linus Torvalds 已提交
1718 1719 1720 1721 1722
			       struct super_block *sb,
			       u32 perms,
			       struct avc_audit_data *ad)
{
	struct superblock_security_struct *sbsec;
1723
	u32 sid = cred_sid(cred);
L
Linus Torvalds 已提交
1724 1725

	sbsec = sb->s_security;
1726
	return avc_has_perm(sid, sbsec->sid, SECCLASS_FILESYSTEM, perms, ad);
L
Linus Torvalds 已提交
1727 1728 1729 1730 1731 1732 1733 1734 1735 1736 1737 1738 1739 1740 1741 1742 1743 1744 1745 1746 1747 1748 1749 1750 1751 1752 1753 1754 1755 1756
}

/* Convert a Linux mode and permission mask to an access vector. */
static inline u32 file_mask_to_av(int mode, int mask)
{
	u32 av = 0;

	if ((mode & S_IFMT) != S_IFDIR) {
		if (mask & MAY_EXEC)
			av |= FILE__EXECUTE;
		if (mask & MAY_READ)
			av |= FILE__READ;

		if (mask & MAY_APPEND)
			av |= FILE__APPEND;
		else if (mask & MAY_WRITE)
			av |= FILE__WRITE;

	} else {
		if (mask & MAY_EXEC)
			av |= DIR__SEARCH;
		if (mask & MAY_WRITE)
			av |= DIR__WRITE;
		if (mask & MAY_READ)
			av |= DIR__READ;
	}

	return av;
}

1757 1758 1759 1760 1761 1762 1763 1764 1765 1766 1767 1768 1769 1770 1771 1772 1773 1774 1775 1776 1777 1778 1779
/* Convert a Linux file to an access vector. */
static inline u32 file_to_av(struct file *file)
{
	u32 av = 0;

	if (file->f_mode & FMODE_READ)
		av |= FILE__READ;
	if (file->f_mode & FMODE_WRITE) {
		if (file->f_flags & O_APPEND)
			av |= FILE__APPEND;
		else
			av |= FILE__WRITE;
	}
	if (!av) {
		/*
		 * Special file opened with flags 3 for ioctl-only use.
		 */
		av = FILE__IOCTL;
	}

	return av;
}

E
Eric Paris 已提交
1780
/*
1781
 * Convert a file to an access vector and include the correct open
E
Eric Paris 已提交
1782 1783
 * open permission.
 */
1784
static inline u32 open_file_to_av(struct file *file)
E
Eric Paris 已提交
1785
{
1786
	u32 av = file_to_av(file);
E
Eric Paris 已提交
1787 1788

	if (selinux_policycap_openperm) {
1789
		mode_t mode = file->f_path.dentry->d_inode->i_mode;
E
Eric Paris 已提交
1790 1791 1792 1793 1794 1795 1796 1797 1798 1799 1800 1801 1802 1803
		/*
		 * lnk files and socks do not really have an 'open'
		 */
		if (S_ISREG(mode))
			av |= FILE__OPEN;
		else if (S_ISCHR(mode))
			av |= CHR_FILE__OPEN;
		else if (S_ISBLK(mode))
			av |= BLK_FILE__OPEN;
		else if (S_ISFIFO(mode))
			av |= FIFO_FILE__OPEN;
		else if (S_ISDIR(mode))
			av |= DIR__OPEN;
		else
E
Eric Paris 已提交
1804
			printk(KERN_ERR "SELinux: WARNING: inside %s with "
1805
				"unknown mode:%o\n", __func__, mode);
E
Eric Paris 已提交
1806 1807 1808 1809
	}
	return av;
}

L
Linus Torvalds 已提交
1810 1811
/* Hook functions begin here. */

1812 1813
static int selinux_ptrace_may_access(struct task_struct *child,
				     unsigned int mode)
L
Linus Torvalds 已提交
1814 1815 1816
{
	int rc;

1817
	rc = secondary_ops->ptrace_may_access(child, mode);
L
Linus Torvalds 已提交
1818 1819 1820
	if (rc)
		return rc;

1821
	if (mode == PTRACE_MODE_READ) {
1822 1823 1824
		u32 sid = current_sid();
		u32 csid = task_sid(child);
		return avc_has_perm(sid, csid, SECCLASS_FILE, FILE__READ, NULL);
1825 1826
	}

1827
	return current_has_perm(child, PROCESS__PTRACE);
1828 1829 1830 1831 1832 1833 1834 1835 1836 1837 1838
}

static int selinux_ptrace_traceme(struct task_struct *parent)
{
	int rc;

	rc = secondary_ops->ptrace_traceme(parent);
	if (rc)
		return rc;

	return task_has_perm(parent, current, PROCESS__PTRACE);
L
Linus Torvalds 已提交
1839 1840 1841
}

static int selinux_capget(struct task_struct *target, kernel_cap_t *effective,
1842
			  kernel_cap_t *inheritable, kernel_cap_t *permitted)
L
Linus Torvalds 已提交
1843 1844 1845
{
	int error;

1846
	error = current_has_perm(target, PROCESS__GETCAP);
L
Linus Torvalds 已提交
1847 1848 1849 1850 1851 1852
	if (error)
		return error;

	return secondary_ops->capget(target, effective, inheritable, permitted);
}

D
David Howells 已提交
1853 1854 1855 1856
static int selinux_capset(struct cred *new, const struct cred *old,
			  const kernel_cap_t *effective,
			  const kernel_cap_t *inheritable,
			  const kernel_cap_t *permitted)
L
Linus Torvalds 已提交
1857 1858 1859
{
	int error;

D
David Howells 已提交
1860 1861
	error = secondary_ops->capset(new, old,
				      effective, inheritable, permitted);
L
Linus Torvalds 已提交
1862 1863 1864
	if (error)
		return error;

D
David Howells 已提交
1865
	return cred_has_perm(old, new, PROCESS__SETCAP);
L
Linus Torvalds 已提交
1866 1867
}

1868
static int selinux_capable(struct task_struct *tsk, int cap, int audit)
L
Linus Torvalds 已提交
1869 1870 1871
{
	int rc;

1872
	rc = secondary_ops->capable(tsk, cap, audit);
L
Linus Torvalds 已提交
1873 1874 1875
	if (rc)
		return rc;

1876
	return task_has_capability(tsk, cap, audit);
L
Linus Torvalds 已提交
1877 1878
}

1879 1880 1881 1882 1883 1884
static int selinux_sysctl_get_sid(ctl_table *table, u16 tclass, u32 *sid)
{
	int buflen, rc;
	char *buffer, *path, *end;

	rc = -ENOMEM;
1885
	buffer = (char *)__get_free_page(GFP_KERNEL);
1886 1887 1888 1889 1890 1891 1892 1893 1894 1895 1896 1897 1898 1899 1900 1901 1902 1903 1904 1905 1906
	if (!buffer)
		goto out;

	buflen = PAGE_SIZE;
	end = buffer+buflen;
	*--end = '\0';
	buflen--;
	path = end-1;
	*path = '/';
	while (table) {
		const char *name = table->procname;
		size_t namelen = strlen(name);
		buflen -= namelen + 1;
		if (buflen < 0)
			goto out_free;
		end -= namelen;
		memcpy(end, name, namelen);
		*--end = '/';
		path = end;
		table = table->parent;
	}
1907 1908 1909 1910 1911 1912
	buflen -= 4;
	if (buflen < 0)
		goto out_free;
	end -= 4;
	memcpy(end, "/sys", 4);
	path = end;
1913 1914 1915 1916 1917 1918 1919
	rc = security_genfs_sid("proc", path, tclass, sid);
out_free:
	free_page((unsigned long)buffer);
out:
	return rc;
}

L
Linus Torvalds 已提交
1920 1921 1922 1923
static int selinux_sysctl(ctl_table *table, int op)
{
	int error = 0;
	u32 av;
1924
	u32 tsid, sid;
L
Linus Torvalds 已提交
1925 1926 1927 1928 1929 1930
	int rc;

	rc = secondary_ops->sysctl(table, op);
	if (rc)
		return rc;

1931
	sid = current_sid();
L
Linus Torvalds 已提交
1932

1933 1934
	rc = selinux_sysctl_get_sid(table, (op == 0001) ?
				    SECCLASS_DIR : SECCLASS_FILE, &tsid);
L
Linus Torvalds 已提交
1935 1936 1937 1938 1939 1940 1941
	if (rc) {
		/* Default to the well-defined sysctl SID. */
		tsid = SECINITSID_SYSCTL;
	}

	/* The op values are "defined" in sysctl.c, thereby creating
	 * a bad coupling between this module and sysctl.c */
1942
	if (op == 001) {
1943
		error = avc_has_perm(sid, tsid,
L
Linus Torvalds 已提交
1944 1945 1946 1947 1948 1949 1950 1951
				     SECCLASS_DIR, DIR__SEARCH, NULL);
	} else {
		av = 0;
		if (op & 004)
			av |= FILE__READ;
		if (op & 002)
			av |= FILE__WRITE;
		if (av)
1952
			error = avc_has_perm(sid, tsid,
L
Linus Torvalds 已提交
1953
					     SECCLASS_FILE, av, NULL);
1954
	}
L
Linus Torvalds 已提交
1955 1956 1957 1958 1959 1960

	return error;
}

static int selinux_quotactl(int cmds, int type, int id, struct super_block *sb)
{
1961
	const struct cred *cred = current_cred();
L
Linus Torvalds 已提交
1962 1963 1964 1965 1966 1967
	int rc = 0;

	if (!sb)
		return 0;

	switch (cmds) {
1968 1969 1970 1971 1972
	case Q_SYNC:
	case Q_QUOTAON:
	case Q_QUOTAOFF:
	case Q_SETINFO:
	case Q_SETQUOTA:
1973
		rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAMOD, NULL);
1974 1975 1976 1977
		break;
	case Q_GETFMT:
	case Q_GETINFO:
	case Q_GETQUOTA:
1978
		rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAGET, NULL);
1979 1980 1981 1982
		break;
	default:
		rc = 0;  /* let the kernel handle invalid cmds */
		break;
L
Linus Torvalds 已提交
1983 1984 1985 1986 1987 1988
	}
	return rc;
}

static int selinux_quota_on(struct dentry *dentry)
{
1989 1990 1991
	const struct cred *cred = current_cred();

	return dentry_has_perm(cred, NULL, dentry, FILE__QUOTAON);
L
Linus Torvalds 已提交
1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002
}

static int selinux_syslog(int type)
{
	int rc;

	rc = secondary_ops->syslog(type);
	if (rc)
		return rc;

	switch (type) {
2003 2004 2005 2006 2007 2008 2009 2010 2011 2012 2013 2014 2015 2016 2017 2018 2019
	case 3:		/* Read last kernel messages */
	case 10:	/* Return size of the log buffer */
		rc = task_has_system(current, SYSTEM__SYSLOG_READ);
		break;
	case 6:		/* Disable logging to console */
	case 7:		/* Enable logging to console */
	case 8:		/* Set level of messages printed to console */
		rc = task_has_system(current, SYSTEM__SYSLOG_CONSOLE);
		break;
	case 0:		/* Close log */
	case 1:		/* Open log */
	case 2:		/* Read from log */
	case 4:		/* Read/clear last kernel messages */
	case 5:		/* Clear ring buffer */
	default:
		rc = task_has_system(current, SYSTEM__SYSLOG_MOD);
		break;
L
Linus Torvalds 已提交
2020 2021 2022 2023 2024 2025 2026 2027 2028 2029 2030 2031 2032 2033 2034 2035
	}
	return rc;
}

/*
 * Check that a process has enough memory to allocate a new virtual
 * mapping. 0 means there is enough memory for the allocation to
 * succeed and -ENOMEM implies there is not.
 *
 * Note that secondary_ops->capable and task_has_perm_noaudit return 0
 * if the capability is granted, but __vm_enough_memory requires 1 if
 * the capability is granted.
 *
 * Do not audit the selinux permission check, as this is applied to all
 * processes that allocate mappings.
 */
2036
static int selinux_vm_enough_memory(struct mm_struct *mm, long pages)
L
Linus Torvalds 已提交
2037 2038 2039
{
	int rc, cap_sys_admin = 0;

2040
	rc = selinux_capable(current, CAP_SYS_ADMIN, SECURITY_CAP_NOAUDIT);
L
Linus Torvalds 已提交
2041 2042 2043
	if (rc == 0)
		cap_sys_admin = 1;

2044
	return __vm_enough_memory(mm, pages, cap_sys_admin);
L
Linus Torvalds 已提交
2045 2046 2047 2048
}

/* binprm security operations */

2049
static int selinux_bprm_set_creds(struct linux_binprm *bprm)
L
Linus Torvalds 已提交
2050
{
2051 2052
	const struct task_security_struct *old_tsec;
	struct task_security_struct *new_tsec;
L
Linus Torvalds 已提交
2053 2054
	struct inode_security_struct *isec;
	struct avc_audit_data ad;
2055
	struct inode *inode = bprm->file->f_path.dentry->d_inode;
L
Linus Torvalds 已提交
2056 2057
	int rc;

2058
	rc = secondary_ops->bprm_set_creds(bprm);
L
Linus Torvalds 已提交
2059 2060 2061
	if (rc)
		return rc;

2062 2063 2064
	/* SELinux context only depends on initial program or script and not
	 * the script interpreter */
	if (bprm->cred_prepared)
L
Linus Torvalds 已提交
2065 2066
		return 0;

2067 2068
	old_tsec = current_security();
	new_tsec = bprm->cred->security;
L
Linus Torvalds 已提交
2069 2070 2071
	isec = inode->i_security;

	/* Default to the current task SID. */
2072 2073
	new_tsec->sid = old_tsec->sid;
	new_tsec->osid = old_tsec->sid;
L
Linus Torvalds 已提交
2074

2075
	/* Reset fs, key, and sock SIDs on execve. */
2076 2077 2078
	new_tsec->create_sid = 0;
	new_tsec->keycreate_sid = 0;
	new_tsec->sockcreate_sid = 0;
L
Linus Torvalds 已提交
2079

2080 2081
	if (old_tsec->exec_sid) {
		new_tsec->sid = old_tsec->exec_sid;
L
Linus Torvalds 已提交
2082
		/* Reset exec SID on execve. */
2083
		new_tsec->exec_sid = 0;
L
Linus Torvalds 已提交
2084 2085
	} else {
		/* Check for a default transition on this program. */
2086 2087
		rc = security_transition_sid(old_tsec->sid, isec->sid,
					     SECCLASS_PROCESS, &new_tsec->sid);
L
Linus Torvalds 已提交
2088 2089 2090 2091 2092
		if (rc)
			return rc;
	}

	AVC_AUDIT_DATA_INIT(&ad, FS);
2093
	ad.u.fs.path = bprm->file->f_path;
L
Linus Torvalds 已提交
2094

J
Josef Sipek 已提交
2095
	if (bprm->file->f_path.mnt->mnt_flags & MNT_NOSUID)
2096
		new_tsec->sid = old_tsec->sid;
L
Linus Torvalds 已提交
2097

2098 2099
	if (new_tsec->sid == old_tsec->sid) {
		rc = avc_has_perm(old_tsec->sid, isec->sid,
L
Linus Torvalds 已提交
2100 2101 2102 2103 2104
				  SECCLASS_FILE, FILE__EXECUTE_NO_TRANS, &ad);
		if (rc)
			return rc;
	} else {
		/* Check permissions for the transition. */
2105
		rc = avc_has_perm(old_tsec->sid, new_tsec->sid,
L
Linus Torvalds 已提交
2106 2107 2108 2109
				  SECCLASS_PROCESS, PROCESS__TRANSITION, &ad);
		if (rc)
			return rc;

2110
		rc = avc_has_perm(new_tsec->sid, isec->sid,
L
Linus Torvalds 已提交
2111 2112 2113 2114
				  SECCLASS_FILE, FILE__ENTRYPOINT, &ad);
		if (rc)
			return rc;

2115 2116 2117 2118 2119 2120 2121 2122 2123 2124 2125 2126 2127 2128 2129 2130 2131 2132 2133 2134 2135 2136 2137 2138 2139 2140 2141 2142 2143 2144 2145 2146 2147
		/* Check for shared state */
		if (bprm->unsafe & LSM_UNSAFE_SHARE) {
			rc = avc_has_perm(old_tsec->sid, new_tsec->sid,
					  SECCLASS_PROCESS, PROCESS__SHARE,
					  NULL);
			if (rc)
				return -EPERM;
		}

		/* Make sure that anyone attempting to ptrace over a task that
		 * changes its SID has the appropriate permit */
		if (bprm->unsafe &
		    (LSM_UNSAFE_PTRACE | LSM_UNSAFE_PTRACE_CAP)) {
			struct task_struct *tracer;
			struct task_security_struct *sec;
			u32 ptsid = 0;

			rcu_read_lock();
			tracer = tracehook_tracer_task(current);
			if (likely(tracer != NULL)) {
				sec = __task_cred(tracer)->security;
				ptsid = sec->sid;
			}
			rcu_read_unlock();

			if (ptsid != 0) {
				rc = avc_has_perm(ptsid, new_tsec->sid,
						  SECCLASS_PROCESS,
						  PROCESS__PTRACE, NULL);
				if (rc)
					return -EPERM;
			}
		}
L
Linus Torvalds 已提交
2148

2149 2150
		/* Clear any possibly unsafe personality bits on exec: */
		bprm->per_clear |= PER_CLEAR_ON_SETID;
L
Linus Torvalds 已提交
2151 2152 2153 2154 2155
	}

	return 0;
}

2156
static int selinux_bprm_check_security(struct linux_binprm *bprm)
L
Linus Torvalds 已提交
2157 2158 2159 2160
{
	return secondary_ops->bprm_check_security(bprm);
}

2161
static int selinux_bprm_secureexec(struct linux_binprm *bprm)
L
Linus Torvalds 已提交
2162
{
2163 2164 2165
	const struct cred *cred = current_cred();
	const struct task_security_struct *tsec = cred->security;
	u32 sid, osid;
L
Linus Torvalds 已提交
2166 2167
	int atsecure = 0;

2168 2169 2170 2171
	sid = tsec->sid;
	osid = tsec->osid;

	if (osid != sid) {
L
Linus Torvalds 已提交
2172 2173 2174
		/* Enable secure mode for SIDs transitions unless
		   the noatsecure permission is granted between
		   the two SIDs, i.e. ahp returns 0. */
2175
		atsecure = avc_has_perm(osid, sid,
2176 2177
					SECCLASS_PROCESS,
					PROCESS__NOATSECURE, NULL);
L
Linus Torvalds 已提交
2178 2179 2180 2181 2182 2183 2184 2185 2186
	}

	return (atsecure || secondary_ops->bprm_secureexec(bprm));
}

extern struct vfsmount *selinuxfs_mount;
extern struct dentry *selinux_null;

/* Derived from fs/exec.c:flush_old_files. */
2187 2188
static inline void flush_unauthorized_files(const struct cred *cred,
					    struct files_struct *files)
L
Linus Torvalds 已提交
2189 2190 2191
{
	struct avc_audit_data ad;
	struct file *file, *devnull = NULL;
2192
	struct tty_struct *tty;
2193
	struct fdtable *fdt;
L
Linus Torvalds 已提交
2194
	long j = -1;
2195
	int drop_tty = 0;
L
Linus Torvalds 已提交
2196

2197
	tty = get_current_tty();
L
Linus Torvalds 已提交
2198 2199
	if (tty) {
		file_list_lock();
2200 2201 2202
		if (!list_empty(&tty->tty_files)) {
			struct inode *inode;

L
Linus Torvalds 已提交
2203 2204 2205 2206 2207
			/* Revalidate access to controlling tty.
			   Use inode_has_perm on the tty inode directly rather
			   than using file_has_perm, as this particular open
			   file may belong to another process and we are only
			   interested in the inode-based check here. */
2208 2209
			file = list_first_entry(&tty->tty_files, struct file, f_u.fu_list);
			inode = file->f_path.dentry->d_inode;
2210
			if (inode_has_perm(cred, inode,
L
Linus Torvalds 已提交
2211
					   FILE__READ | FILE__WRITE, NULL)) {
2212
				drop_tty = 1;
L
Linus Torvalds 已提交
2213 2214 2215
			}
		}
		file_list_unlock();
A
Alan Cox 已提交
2216
		tty_kref_put(tty);
L
Linus Torvalds 已提交
2217
	}
2218 2219 2220
	/* Reset controlling tty. */
	if (drop_tty)
		no_tty();
L
Linus Torvalds 已提交
2221 2222 2223

	/* Revalidate access to inherited open files. */

2224
	AVC_AUDIT_DATA_INIT(&ad, FS);
L
Linus Torvalds 已提交
2225 2226 2227 2228 2229 2230 2231 2232

	spin_lock(&files->file_lock);
	for (;;) {
		unsigned long set, i;
		int fd;

		j++;
		i = j * __NFDBITS;
2233
		fdt = files_fdtable(files);
2234
		if (i >= fdt->max_fds)
L
Linus Torvalds 已提交
2235
			break;
2236
		set = fdt->open_fds->fds_bits[j];
L
Linus Torvalds 已提交
2237 2238 2239
		if (!set)
			continue;
		spin_unlock(&files->file_lock);
2240
		for ( ; set ; i++, set >>= 1) {
L
Linus Torvalds 已提交
2241 2242 2243 2244
			if (set & 1) {
				file = fget(i);
				if (!file)
					continue;
2245
				if (file_has_perm(cred,
L
Linus Torvalds 已提交
2246 2247 2248 2249 2250 2251 2252 2253 2254 2255 2256
						  file,
						  file_to_av(file))) {
					sys_close(i);
					fd = get_unused_fd();
					if (fd != i) {
						if (fd >= 0)
							put_unused_fd(fd);
						fput(file);
						continue;
					}
					if (devnull) {
2257
						get_file(devnull);
L
Linus Torvalds 已提交
2258
					} else {
2259 2260 2261 2262
						devnull = dentry_open(
							dget(selinux_null),
							mntget(selinuxfs_mount),
							O_RDWR, cred);
2263 2264
						if (IS_ERR(devnull)) {
							devnull = NULL;
L
Linus Torvalds 已提交
2265 2266 2267 2268 2269 2270 2271 2272 2273 2274 2275 2276 2277 2278 2279 2280
							put_unused_fd(fd);
							fput(file);
							continue;
						}
					}
					fd_install(fd, devnull);
				}
				fput(file);
			}
		}
		spin_lock(&files->file_lock);

	}
	spin_unlock(&files->file_lock);
}

2281 2282 2283 2284
/*
 * Prepare a process for imminent new credential changes due to exec
 */
static void selinux_bprm_committing_creds(struct linux_binprm *bprm)
L
Linus Torvalds 已提交
2285
{
2286 2287 2288
	struct task_security_struct *new_tsec;
	struct rlimit *rlim, *initrlim;
	int rc, i;
D
David Howells 已提交
2289

2290
	secondary_ops->bprm_committing_creds(bprm);
L
Linus Torvalds 已提交
2291

2292 2293 2294
	new_tsec = bprm->cred->security;
	if (new_tsec->sid == new_tsec->osid)
		return;
L
Linus Torvalds 已提交
2295

2296 2297
	/* Close files for which the new task SID is not authorized. */
	flush_unauthorized_files(bprm->cred, current->files);
R
Roland McGrath 已提交
2298

2299 2300
	/* Always clear parent death signal on SID transitions. */
	current->pdeath_signal = 0;
R
Roland McGrath 已提交
2301

2302 2303 2304 2305 2306 2307 2308 2309 2310 2311 2312 2313 2314 2315 2316 2317 2318
	/* Check whether the new SID can inherit resource limits from the old
	 * SID.  If not, reset all soft limits to the lower of the current
	 * task's hard limit and the init task's soft limit.
	 *
	 * Note that the setting of hard limits (even to lower them) can be
	 * controlled by the setrlimit check.  The inclusion of the init task's
	 * soft limit into the computation is to avoid resetting soft limits
	 * higher than the default soft limit for cases where the default is
	 * lower than the hard limit, e.g. RLIMIT_CORE or RLIMIT_STACK.
	 */
	rc = avc_has_perm(new_tsec->osid, new_tsec->sid, SECCLASS_PROCESS,
			  PROCESS__RLIMITINH, NULL);
	if (rc) {
		for (i = 0; i < RLIM_NLIMITS; i++) {
			rlim = current->signal->rlim + i;
			initrlim = init_task.signal->rlim + i;
			rlim->rlim_cur = min(rlim->rlim_max, initrlim->rlim_cur);
L
Linus Torvalds 已提交
2319
		}
2320
		update_rlimit_cpu(rlim->rlim_cur);
L
Linus Torvalds 已提交
2321 2322 2323 2324
	}
}

/*
2325 2326
 * Clean up the process immediately after the installation of new credentials
 * due to exec
L
Linus Torvalds 已提交
2327
 */
2328
static void selinux_bprm_committed_creds(struct linux_binprm *bprm)
L
Linus Torvalds 已提交
2329
{
2330
	const struct task_security_struct *tsec = current_security();
L
Linus Torvalds 已提交
2331
	struct itimerval itimer;
2332
	struct sighand_struct *psig;
2333
	u32 osid, sid;
L
Linus Torvalds 已提交
2334
	int rc, i;
2335
	unsigned long flags;
L
Linus Torvalds 已提交
2336

2337
	secondary_ops->bprm_committed_creds(bprm);
L
Linus Torvalds 已提交
2338

2339 2340 2341 2342
	osid = tsec->osid;
	sid = tsec->sid;

	if (sid == osid)
L
Linus Torvalds 已提交
2343 2344
		return;

2345 2346 2347 2348 2349 2350 2351 2352
	/* Check whether the new SID can inherit signal state from the old SID.
	 * If not, clear itimers to avoid subsequent signal generation and
	 * flush and unblock signals.
	 *
	 * This must occur _after_ the task SID has been updated so that any
	 * kill done after the flush will be checked against the new SID.
	 */
	rc = avc_has_perm(osid, sid, SECCLASS_PROCESS, PROCESS__SIGINH, NULL);
L
Linus Torvalds 已提交
2353 2354 2355 2356 2357 2358 2359 2360 2361 2362 2363 2364
	if (rc) {
		memset(&itimer, 0, sizeof itimer);
		for (i = 0; i < 3; i++)
			do_setitimer(i, &itimer, NULL);
		flush_signals(current);
		spin_lock_irq(&current->sighand->siglock);
		flush_signal_handlers(current, 1);
		sigemptyset(&current->blocked);
		recalc_sigpending();
		spin_unlock_irq(&current->sighand->siglock);
	}

2365 2366
	/* Wake up the parent if it is waiting so that it can recheck
	 * wait permission to the new task SID. */
2367 2368 2369
	read_lock_irq(&tasklist_lock);
	psig = current->parent->sighand;
	spin_lock_irqsave(&psig->siglock, flags);
L
Linus Torvalds 已提交
2370
	wake_up_interruptible(&current->parent->signal->wait_chldexit);
2371 2372
	spin_unlock_irqrestore(&psig->siglock, flags);
	read_unlock_irq(&tasklist_lock);
L
Linus Torvalds 已提交
2373 2374 2375 2376 2377 2378 2379 2380 2381 2382 2383 2384 2385 2386 2387 2388 2389 2390 2391 2392 2393 2394 2395 2396
}

/* superblock security operations */

static int selinux_sb_alloc_security(struct super_block *sb)
{
	return superblock_alloc_security(sb);
}

static void selinux_sb_free_security(struct super_block *sb)
{
	superblock_free_security(sb);
}

static inline int match_prefix(char *prefix, int plen, char *option, int olen)
{
	if (plen > olen)
		return 0;

	return !memcmp(prefix, option, plen);
}

static inline int selinux_option(char *option, int len)
{
2397 2398 2399 2400
	return (match_prefix(CONTEXT_STR, sizeof(CONTEXT_STR)-1, option, len) ||
		match_prefix(FSCONTEXT_STR, sizeof(FSCONTEXT_STR)-1, option, len) ||
		match_prefix(DEFCONTEXT_STR, sizeof(DEFCONTEXT_STR)-1, option, len) ||
		match_prefix(ROOTCONTEXT_STR, sizeof(ROOTCONTEXT_STR)-1, option, len));
L
Linus Torvalds 已提交
2401 2402 2403 2404 2405 2406 2407
}

static inline void take_option(char **to, char *from, int *first, int len)
{
	if (!*first) {
		**to = ',';
		*to += 1;
2408
	} else
L
Linus Torvalds 已提交
2409 2410 2411 2412 2413
		*first = 0;
	memcpy(*to, from, len);
	*to += len;
}

2414 2415
static inline void take_selinux_option(char **to, char *from, int *first,
				       int len)
2416 2417 2418 2419 2420 2421
{
	int current_size = 0;

	if (!*first) {
		**to = '|';
		*to += 1;
2422
	} else
2423 2424 2425 2426 2427 2428 2429 2430 2431 2432 2433 2434
		*first = 0;

	while (current_size < len) {
		if (*from != '"') {
			**to = *from;
			*to += 1;
		}
		from += 1;
		current_size += 1;
	}
}

2435
static int selinux_sb_copy_data(char *orig, char *copy)
L
Linus Torvalds 已提交
2436 2437 2438 2439
{
	int fnosec, fsec, rc = 0;
	char *in_save, *in_curr, *in_end;
	char *sec_curr, *nosec_save, *nosec;
2440
	int open_quote = 0;
L
Linus Torvalds 已提交
2441 2442 2443 2444 2445 2446 2447 2448 2449 2450 2451 2452 2453 2454 2455

	in_curr = orig;
	sec_curr = copy;

	nosec = (char *)get_zeroed_page(GFP_KERNEL);
	if (!nosec) {
		rc = -ENOMEM;
		goto out;
	}

	nosec_save = nosec;
	fnosec = fsec = 1;
	in_save = in_end = orig;

	do {
2456 2457 2458 2459
		if (*in_end == '"')
			open_quote = !open_quote;
		if ((*in_end == ',' && open_quote == 0) ||
				*in_end == '\0') {
L
Linus Torvalds 已提交
2460 2461 2462
			int len = in_end - in_curr;

			if (selinux_option(in_curr, len))
2463
				take_selinux_option(&sec_curr, in_curr, &fsec, len);
L
Linus Torvalds 已提交
2464 2465 2466 2467 2468 2469 2470
			else
				take_option(&nosec, in_curr, &fnosec, len);

			in_curr = in_end + 1;
		}
	} while (*in_end++);

2471
	strcpy(in_save, nosec_save);
2472
	free_page((unsigned long)nosec_save);
L
Linus Torvalds 已提交
2473 2474 2475 2476
out:
	return rc;
}

2477
static int selinux_sb_kern_mount(struct super_block *sb, int flags, void *data)
L
Linus Torvalds 已提交
2478
{
2479
	const struct cred *cred = current_cred();
L
Linus Torvalds 已提交
2480 2481 2482 2483 2484 2485 2486
	struct avc_audit_data ad;
	int rc;

	rc = superblock_doinit(sb, data);
	if (rc)
		return rc;

2487
	AVC_AUDIT_DATA_INIT(&ad, FS);
2488
	ad.u.fs.path.dentry = sb->s_root;
2489
	return superblock_has_perm(cred, sb, FILESYSTEM__MOUNT, &ad);
L
Linus Torvalds 已提交
2490 2491
}

2492
static int selinux_sb_statfs(struct dentry *dentry)
L
Linus Torvalds 已提交
2493
{
2494
	const struct cred *cred = current_cred();
L
Linus Torvalds 已提交
2495 2496
	struct avc_audit_data ad;

2497
	AVC_AUDIT_DATA_INIT(&ad, FS);
2498
	ad.u.fs.path.dentry = dentry->d_sb->s_root;
2499
	return superblock_has_perm(cred, dentry->d_sb, FILESYSTEM__GETATTR, &ad);
L
Linus Torvalds 已提交
2500 2501
}

2502
static int selinux_mount(char *dev_name,
2503
			 struct path *path,
2504 2505 2506
			 char *type,
			 unsigned long flags,
			 void *data)
L
Linus Torvalds 已提交
2507
{
2508
	const struct cred *cred = current_cred();
L
Linus Torvalds 已提交
2509 2510
	int rc;

2511
	rc = secondary_ops->sb_mount(dev_name, path, type, flags, data);
L
Linus Torvalds 已提交
2512 2513 2514 2515
	if (rc)
		return rc;

	if (flags & MS_REMOUNT)
2516
		return superblock_has_perm(cred, path->mnt->mnt_sb,
2517
					   FILESYSTEM__REMOUNT, NULL);
L
Linus Torvalds 已提交
2518
	else
2519
		return dentry_has_perm(cred, path->mnt, path->dentry,
2520
				       FILE__MOUNTON);
L
Linus Torvalds 已提交
2521 2522 2523 2524
}

static int selinux_umount(struct vfsmount *mnt, int flags)
{
2525
	const struct cred *cred = current_cred();
L
Linus Torvalds 已提交
2526 2527 2528 2529 2530 2531
	int rc;

	rc = secondary_ops->sb_umount(mnt, flags);
	if (rc)
		return rc;

2532
	return superblock_has_perm(cred, mnt->mnt_sb,
2533
				   FILESYSTEM__UNMOUNT, NULL);
L
Linus Torvalds 已提交
2534 2535 2536 2537 2538 2539 2540 2541 2542 2543 2544 2545 2546 2547
}

/* inode security operations */

static int selinux_inode_alloc_security(struct inode *inode)
{
	return inode_alloc_security(inode);
}

static void selinux_inode_free_security(struct inode *inode)
{
	inode_free_security(inode);
}

2548 2549 2550 2551
static int selinux_inode_init_security(struct inode *inode, struct inode *dir,
				       char **name, void **value,
				       size_t *len)
{
2552 2553
	const struct cred *cred = current_cred();
	const struct task_security_struct *tsec = cred->security;
2554 2555
	struct inode_security_struct *dsec;
	struct superblock_security_struct *sbsec;
2556
	u32 sid, newsid, clen;
2557
	int rc;
2558
	char *namep = NULL, *context;
2559 2560 2561 2562

	dsec = dir->i_security;
	sbsec = dir->i_sb->s_security;

2563 2564 2565 2566 2567
	sid = tsec->sid;
	newsid = tsec->create_sid;

	if (!newsid || sbsec->behavior == SECURITY_FS_USE_MNTPOINT) {
		rc = security_transition_sid(sid, dsec->sid,
2568 2569 2570 2571 2572 2573
					     inode_mode_to_security_class(inode->i_mode),
					     &newsid);
		if (rc) {
			printk(KERN_WARNING "%s:  "
			       "security_transition_sid failed, rc=%d (dev=%s "
			       "ino=%ld)\n",
2574
			       __func__,
2575 2576 2577 2578 2579
			       -rc, inode->i_sb->s_id, inode->i_ino);
			return rc;
		}
	}

2580 2581 2582 2583 2584 2585 2586
	/* Possibly defer initialization to selinux_complete_init. */
	if (sbsec->initialized) {
		struct inode_security_struct *isec = inode->i_security;
		isec->sclass = inode_mode_to_security_class(inode->i_mode);
		isec->sid = newsid;
		isec->initialized = 1;
	}
2587

2588
	if (!ss_initialized || sbsec->behavior == SECURITY_FS_USE_MNTPOINT)
2589 2590
		return -EOPNOTSUPP;

2591
	if (name) {
2592
		namep = kstrdup(XATTR_SELINUX_SUFFIX, GFP_NOFS);
2593 2594 2595 2596
		if (!namep)
			return -ENOMEM;
		*name = namep;
	}
2597

2598
	if (value && len) {
2599
		rc = security_sid_to_context_force(newsid, &context, &clen);
2600 2601 2602 2603 2604 2605
		if (rc) {
			kfree(namep);
			return rc;
		}
		*value = context;
		*len = clen;
2606 2607 2608 2609 2610
	}

	return 0;
}

L
Linus Torvalds 已提交
2611 2612 2613 2614 2615 2616 2617 2618 2619
static int selinux_inode_create(struct inode *dir, struct dentry *dentry, int mask)
{
	return may_create(dir, dentry, SECCLASS_FILE);
}

static int selinux_inode_link(struct dentry *old_dentry, struct inode *dir, struct dentry *new_dentry)
{
	int rc;

2620
	rc = secondary_ops->inode_link(old_dentry, dir, new_dentry);
L
Linus Torvalds 已提交
2621 2622 2623 2624 2625 2626 2627 2628 2629 2630 2631 2632 2633 2634 2635 2636 2637 2638 2639 2640 2641 2642 2643 2644 2645 2646 2647 2648 2649 2650 2651 2652 2653 2654 2655 2656 2657 2658 2659 2660 2661 2662
	if (rc)
		return rc;
	return may_link(dir, old_dentry, MAY_LINK);
}

static int selinux_inode_unlink(struct inode *dir, struct dentry *dentry)
{
	int rc;

	rc = secondary_ops->inode_unlink(dir, dentry);
	if (rc)
		return rc;
	return may_link(dir, dentry, MAY_UNLINK);
}

static int selinux_inode_symlink(struct inode *dir, struct dentry *dentry, const char *name)
{
	return may_create(dir, dentry, SECCLASS_LNK_FILE);
}

static int selinux_inode_mkdir(struct inode *dir, struct dentry *dentry, int mask)
{
	return may_create(dir, dentry, SECCLASS_DIR);
}

static int selinux_inode_rmdir(struct inode *dir, struct dentry *dentry)
{
	return may_link(dir, dentry, MAY_RMDIR);
}

static int selinux_inode_mknod(struct inode *dir, struct dentry *dentry, int mode, dev_t dev)
{
	int rc;

	rc = secondary_ops->inode_mknod(dir, dentry, mode, dev);
	if (rc)
		return rc;

	return may_create(dir, dentry, inode_mode_to_security_class(mode));
}

static int selinux_inode_rename(struct inode *old_inode, struct dentry *old_dentry,
2663
				struct inode *new_inode, struct dentry *new_dentry)
L
Linus Torvalds 已提交
2664 2665 2666 2667 2668 2669
{
	return may_rename(old_inode, old_dentry, new_inode, new_dentry);
}

static int selinux_inode_readlink(struct dentry *dentry)
{
2670 2671 2672
	const struct cred *cred = current_cred();

	return dentry_has_perm(cred, NULL, dentry, FILE__READ);
L
Linus Torvalds 已提交
2673 2674 2675 2676
}

static int selinux_inode_follow_link(struct dentry *dentry, struct nameidata *nameidata)
{
2677
	const struct cred *cred = current_cred();
L
Linus Torvalds 已提交
2678 2679
	int rc;

2680
	rc = secondary_ops->inode_follow_link(dentry, nameidata);
L
Linus Torvalds 已提交
2681 2682
	if (rc)
		return rc;
2683
	return dentry_has_perm(cred, NULL, dentry, FILE__READ);
L
Linus Torvalds 已提交
2684 2685
}

2686
static int selinux_inode_permission(struct inode *inode, int mask)
L
Linus Torvalds 已提交
2687
{
2688
	const struct cred *cred = current_cred();
L
Linus Torvalds 已提交
2689 2690
	int rc;

2691
	rc = secondary_ops->inode_permission(inode, mask);
L
Linus Torvalds 已提交
2692 2693 2694 2695 2696 2697 2698 2699
	if (rc)
		return rc;

	if (!mask) {
		/* No permission to check.  Existence test. */
		return 0;
	}

2700
	return inode_has_perm(cred, inode,
2701
			      file_mask_to_av(inode->i_mode, mask), NULL);
L
Linus Torvalds 已提交
2702 2703 2704 2705
}

static int selinux_inode_setattr(struct dentry *dentry, struct iattr *iattr)
{
2706
	const struct cred *cred = current_cred();
L
Linus Torvalds 已提交
2707 2708 2709 2710 2711 2712 2713 2714 2715 2716 2717
	int rc;

	rc = secondary_ops->inode_setattr(dentry, iattr);
	if (rc)
		return rc;

	if (iattr->ia_valid & ATTR_FORCE)
		return 0;

	if (iattr->ia_valid & (ATTR_MODE | ATTR_UID | ATTR_GID |
			       ATTR_ATIME_SET | ATTR_MTIME_SET))
2718
		return dentry_has_perm(cred, NULL, dentry, FILE__SETATTR);
L
Linus Torvalds 已提交
2719

2720
	return dentry_has_perm(cred, NULL, dentry, FILE__WRITE);
L
Linus Torvalds 已提交
2721 2722 2723 2724
}

static int selinux_inode_getattr(struct vfsmount *mnt, struct dentry *dentry)
{
2725 2726 2727
	const struct cred *cred = current_cred();

	return dentry_has_perm(cred, mnt, dentry, FILE__GETATTR);
L
Linus Torvalds 已提交
2728 2729
}

2730
static int selinux_inode_setotherxattr(struct dentry *dentry, const char *name)
2731
{
2732 2733
	const struct cred *cred = current_cred();

2734 2735 2736 2737 2738 2739 2740 2741 2742 2743 2744 2745 2746 2747
	if (!strncmp(name, XATTR_SECURITY_PREFIX,
		     sizeof XATTR_SECURITY_PREFIX - 1)) {
		if (!strcmp(name, XATTR_NAME_CAPS)) {
			if (!capable(CAP_SETFCAP))
				return -EPERM;
		} else if (!capable(CAP_SYS_ADMIN)) {
			/* A different attribute in the security namespace.
			   Restrict to administrator. */
			return -EPERM;
		}
	}

	/* Not an attribute we recognize, so just check the
	   ordinary setattr permission. */
2748
	return dentry_has_perm(cred, NULL, dentry, FILE__SETATTR);
2749 2750
}

2751 2752
static int selinux_inode_setxattr(struct dentry *dentry, const char *name,
				  const void *value, size_t size, int flags)
L
Linus Torvalds 已提交
2753 2754 2755 2756 2757
{
	struct inode *inode = dentry->d_inode;
	struct inode_security_struct *isec = inode->i_security;
	struct superblock_security_struct *sbsec;
	struct avc_audit_data ad;
2758
	u32 newsid, sid = current_sid();
L
Linus Torvalds 已提交
2759 2760
	int rc = 0;

2761 2762
	if (strcmp(name, XATTR_NAME_SELINUX))
		return selinux_inode_setotherxattr(dentry, name);
L
Linus Torvalds 已提交
2763 2764 2765 2766 2767

	sbsec = inode->i_sb->s_security;
	if (sbsec->behavior == SECURITY_FS_USE_MNTPOINT)
		return -EOPNOTSUPP;

2768
	if (!is_owner_or_cap(inode))
L
Linus Torvalds 已提交
2769 2770
		return -EPERM;

2771
	AVC_AUDIT_DATA_INIT(&ad, FS);
2772
	ad.u.fs.path.dentry = dentry;
L
Linus Torvalds 已提交
2773

2774
	rc = avc_has_perm(sid, isec->sid, isec->sclass,
L
Linus Torvalds 已提交
2775 2776 2777 2778 2779
			  FILE__RELABELFROM, &ad);
	if (rc)
		return rc;

	rc = security_context_to_sid(value, size, &newsid);
2780 2781 2782 2783 2784
	if (rc == -EINVAL) {
		if (!capable(CAP_MAC_ADMIN))
			return rc;
		rc = security_context_to_sid_force(value, size, &newsid);
	}
L
Linus Torvalds 已提交
2785 2786 2787
	if (rc)
		return rc;

2788
	rc = avc_has_perm(sid, newsid, isec->sclass,
L
Linus Torvalds 已提交
2789 2790 2791 2792
			  FILE__RELABELTO, &ad);
	if (rc)
		return rc;

2793
	rc = security_validate_transition(isec->sid, newsid, sid,
2794
					  isec->sclass);
L
Linus Torvalds 已提交
2795 2796 2797 2798 2799 2800 2801 2802 2803 2804
	if (rc)
		return rc;

	return avc_has_perm(newsid,
			    sbsec->sid,
			    SECCLASS_FILESYSTEM,
			    FILESYSTEM__ASSOCIATE,
			    &ad);
}

2805
static void selinux_inode_post_setxattr(struct dentry *dentry, const char *name,
2806
					const void *value, size_t size,
2807
					int flags)
L
Linus Torvalds 已提交
2808 2809 2810 2811 2812 2813 2814 2815 2816 2817 2818
{
	struct inode *inode = dentry->d_inode;
	struct inode_security_struct *isec = inode->i_security;
	u32 newsid;
	int rc;

	if (strcmp(name, XATTR_NAME_SELINUX)) {
		/* Not an attribute we recognize, so nothing to do. */
		return;
	}

2819
	rc = security_context_to_sid_force(value, size, &newsid);
L
Linus Torvalds 已提交
2820
	if (rc) {
2821 2822 2823
		printk(KERN_ERR "SELinux:  unable to map context to SID"
		       "for (%s, %lu), rc=%d\n",
		       inode->i_sb->s_id, inode->i_ino, -rc);
L
Linus Torvalds 已提交
2824 2825 2826 2827 2828 2829 2830
		return;
	}

	isec->sid = newsid;
	return;
}

2831
static int selinux_inode_getxattr(struct dentry *dentry, const char *name)
L
Linus Torvalds 已提交
2832
{
2833 2834 2835
	const struct cred *cred = current_cred();

	return dentry_has_perm(cred, NULL, dentry, FILE__GETATTR);
L
Linus Torvalds 已提交
2836 2837
}

2838
static int selinux_inode_listxattr(struct dentry *dentry)
L
Linus Torvalds 已提交
2839
{
2840 2841 2842
	const struct cred *cred = current_cred();

	return dentry_has_perm(cred, NULL, dentry, FILE__GETATTR);
L
Linus Torvalds 已提交
2843 2844
}

2845
static int selinux_inode_removexattr(struct dentry *dentry, const char *name)
L
Linus Torvalds 已提交
2846
{
2847 2848
	if (strcmp(name, XATTR_NAME_SELINUX))
		return selinux_inode_setotherxattr(dentry, name);
L
Linus Torvalds 已提交
2849 2850 2851 2852 2853 2854

	/* No one is allowed to remove a SELinux security label.
	   You can change the label, but all data must be labeled. */
	return -EACCES;
}

2855
/*
2856
 * Copy the inode security context value to the user.
2857 2858 2859
 *
 * Permission check is handled by selinux_inode_getxattr hook.
 */
2860
static int selinux_inode_getsecurity(const struct inode *inode, const char *name, void **buffer, bool alloc)
L
Linus Torvalds 已提交
2861
{
2862 2863 2864
	u32 size;
	int error;
	char *context = NULL;
L
Linus Torvalds 已提交
2865
	struct inode_security_struct *isec = inode->i_security;
2866

2867 2868
	if (strcmp(name, XATTR_SELINUX_SUFFIX))
		return -EOPNOTSUPP;
2869

2870 2871 2872 2873 2874 2875 2876 2877 2878
	/*
	 * If the caller has CAP_MAC_ADMIN, then get the raw context
	 * value even if it is not defined by current policy; otherwise,
	 * use the in-core value under current policy.
	 * Use the non-auditing forms of the permission checks since
	 * getxattr may be called by unprivileged processes commonly
	 * and lack of permission just means that we fall back to the
	 * in-core context value, not a denial.
	 */
2879
	error = selinux_capable(current, CAP_MAC_ADMIN, SECURITY_CAP_NOAUDIT);
2880 2881 2882 2883 2884
	if (!error)
		error = security_sid_to_context_force(isec->sid, &context,
						      &size);
	else
		error = security_sid_to_context(isec->sid, &context, &size);
2885 2886 2887 2888 2889 2890 2891 2892 2893 2894
	if (error)
		return error;
	error = size;
	if (alloc) {
		*buffer = context;
		goto out_nofree;
	}
	kfree(context);
out_nofree:
	return error;
L
Linus Torvalds 已提交
2895 2896 2897
}

static int selinux_inode_setsecurity(struct inode *inode, const char *name,
2898
				     const void *value, size_t size, int flags)
L
Linus Torvalds 已提交
2899 2900 2901 2902 2903 2904 2905 2906 2907 2908 2909
{
	struct inode_security_struct *isec = inode->i_security;
	u32 newsid;
	int rc;

	if (strcmp(name, XATTR_SELINUX_SUFFIX))
		return -EOPNOTSUPP;

	if (!value || !size)
		return -EACCES;

2910
	rc = security_context_to_sid((void *)value, size, &newsid);
L
Linus Torvalds 已提交
2911 2912 2913 2914 2915 2916 2917 2918 2919 2920 2921 2922 2923 2924 2925
	if (rc)
		return rc;

	isec->sid = newsid;
	return 0;
}

static int selinux_inode_listsecurity(struct inode *inode, char *buffer, size_t buffer_size)
{
	const int len = sizeof(XATTR_NAME_SELINUX);
	if (buffer && len <= buffer_size)
		memcpy(buffer, XATTR_NAME_SELINUX, len);
	return len;
}

2926 2927 2928 2929 2930 2931 2932 2933 2934 2935
static int selinux_inode_need_killpriv(struct dentry *dentry)
{
	return secondary_ops->inode_need_killpriv(dentry);
}

static int selinux_inode_killpriv(struct dentry *dentry)
{
	return secondary_ops->inode_killpriv(dentry);
}

2936 2937 2938 2939 2940 2941
static void selinux_inode_getsecid(const struct inode *inode, u32 *secid)
{
	struct inode_security_struct *isec = inode->i_security;
	*secid = isec->sid;
}

L
Linus Torvalds 已提交
2942 2943
/* file security operations */

2944
static int selinux_revalidate_file_permission(struct file *file, int mask)
L
Linus Torvalds 已提交
2945
{
2946
	const struct cred *cred = current_cred();
V
Venkat Yekkirala 已提交
2947
	int rc;
J
Josef Sipek 已提交
2948
	struct inode *inode = file->f_path.dentry->d_inode;
L
Linus Torvalds 已提交
2949 2950 2951 2952 2953 2954 2955 2956 2957 2958

	if (!mask) {
		/* No permission to check.  Existence test. */
		return 0;
	}

	/* file_mask_to_av won't add FILE__WRITE if MAY_APPEND is set */
	if ((file->f_flags & O_APPEND) && (mask & MAY_WRITE))
		mask |= MAY_APPEND;

2959
	rc = file_has_perm(cred, file,
V
Venkat Yekkirala 已提交
2960 2961 2962 2963 2964
			   file_mask_to_av(inode->i_mode, mask));
	if (rc)
		return rc;

	return selinux_netlbl_inode_permission(inode, mask);
L
Linus Torvalds 已提交
2965 2966
}

2967 2968 2969 2970 2971
static int selinux_file_permission(struct file *file, int mask)
{
	struct inode *inode = file->f_path.dentry->d_inode;
	struct file_security_struct *fsec = file->f_security;
	struct inode_security_struct *isec = inode->i_security;
2972
	u32 sid = current_sid();
2973 2974 2975 2976 2977 2978

	if (!mask) {
		/* No permission to check.  Existence test. */
		return 0;
	}

2979
	if (sid == fsec->sid && fsec->isid == isec->sid
2980 2981 2982 2983 2984 2985
	    && fsec->pseqno == avc_policy_seqno())
		return selinux_netlbl_inode_permission(inode, mask);

	return selinux_revalidate_file_permission(file, mask);
}

L
Linus Torvalds 已提交
2986 2987 2988 2989 2990 2991 2992 2993 2994 2995 2996 2997 2998
static int selinux_file_alloc_security(struct file *file)
{
	return file_alloc_security(file);
}

static void selinux_file_free_security(struct file *file)
{
	file_free_security(file);
}

static int selinux_file_ioctl(struct file *file, unsigned int cmd,
			      unsigned long arg)
{
2999
	const struct cred *cred = current_cred();
3000
	u32 av = 0;
L
Linus Torvalds 已提交
3001

3002 3003 3004 3005 3006 3007
	if (_IOC_DIR(cmd) & _IOC_WRITE)
		av |= FILE__WRITE;
	if (_IOC_DIR(cmd) & _IOC_READ)
		av |= FILE__READ;
	if (!av)
		av = FILE__IOCTL;
L
Linus Torvalds 已提交
3008

3009
	return file_has_perm(cred, file, av);
L
Linus Torvalds 已提交
3010 3011 3012 3013
}

static int file_map_prot_check(struct file *file, unsigned long prot, int shared)
{
3014
	const struct cred *cred = current_cred();
D
David Howells 已提交
3015
	int rc = 0;
3016

L
Linus Torvalds 已提交
3017 3018 3019 3020 3021 3022 3023
#ifndef CONFIG_PPC32
	if ((prot & PROT_EXEC) && (!file || (!shared && (prot & PROT_WRITE)))) {
		/*
		 * We are making executable an anonymous mapping or a
		 * private file mapping that will also be writable.
		 * This has an additional check.
		 */
D
David Howells 已提交
3024
		rc = cred_has_perm(cred, cred, PROCESS__EXECMEM);
L
Linus Torvalds 已提交
3025
		if (rc)
D
David Howells 已提交
3026
			goto error;
L
Linus Torvalds 已提交
3027 3028 3029 3030 3031 3032 3033 3034 3035 3036 3037 3038 3039 3040
	}
#endif

	if (file) {
		/* read access is always possible with a mapping */
		u32 av = FILE__READ;

		/* write access only matters if the mapping is shared */
		if (shared && (prot & PROT_WRITE))
			av |= FILE__WRITE;

		if (prot & PROT_EXEC)
			av |= FILE__EXECUTE;

3041
		return file_has_perm(cred, file, av);
L
Linus Torvalds 已提交
3042
	}
D
David Howells 已提交
3043 3044 3045

error:
	return rc;
L
Linus Torvalds 已提交
3046 3047 3048
}

static int selinux_file_mmap(struct file *file, unsigned long reqprot,
3049 3050
			     unsigned long prot, unsigned long flags,
			     unsigned long addr, unsigned long addr_only)
L
Linus Torvalds 已提交
3051
{
3052
	int rc = 0;
3053
	u32 sid = current_sid();
L
Linus Torvalds 已提交
3054

3055 3056 3057 3058
	if (addr < mmap_min_addr)
		rc = avc_has_perm(sid, sid, SECCLASS_MEMPROTECT,
				  MEMPROTECT__MMAP_ZERO, NULL);
	if (rc || addr_only)
L
Linus Torvalds 已提交
3059 3060 3061 3062 3063 3064 3065 3066 3067 3068 3069 3070 3071
		return rc;

	if (selinux_checkreqprot)
		prot = reqprot;

	return file_map_prot_check(file, prot,
				   (flags & MAP_TYPE) == MAP_SHARED);
}

static int selinux_file_mprotect(struct vm_area_struct *vma,
				 unsigned long reqprot,
				 unsigned long prot)
{
3072
	const struct cred *cred = current_cred();
L
Linus Torvalds 已提交
3073 3074 3075 3076 3077 3078 3079 3080 3081 3082
	int rc;

	rc = secondary_ops->file_mprotect(vma, reqprot, prot);
	if (rc)
		return rc;

	if (selinux_checkreqprot)
		prot = reqprot;

#ifndef CONFIG_PPC32
3083 3084 3085 3086
	if ((prot & PROT_EXEC) && !(vma->vm_flags & VM_EXEC)) {
		rc = 0;
		if (vma->vm_start >= vma->vm_mm->start_brk &&
		    vma->vm_end <= vma->vm_mm->brk) {
D
David Howells 已提交
3087
			rc = cred_has_perm(cred, cred, PROCESS__EXECHEAP);
3088 3089 3090
		} else if (!vma->vm_file &&
			   vma->vm_start <= vma->vm_mm->start_stack &&
			   vma->vm_end >= vma->vm_mm->start_stack) {
3091
			rc = current_has_perm(current, PROCESS__EXECSTACK);
3092 3093 3094 3095 3096 3097 3098 3099
		} else if (vma->vm_file && vma->anon_vma) {
			/*
			 * We are making executable a file mapping that has
			 * had some COW done. Since pages might have been
			 * written, check ability to execute the possibly
			 * modified content.  This typically should only
			 * occur for text relocations.
			 */
D
David Howells 已提交
3100
			rc = file_has_perm(cred, vma->vm_file, FILE__EXECMOD);
3101
		}
3102 3103 3104
		if (rc)
			return rc;
	}
L
Linus Torvalds 已提交
3105 3106 3107 3108 3109 3110 3111
#endif

	return file_map_prot_check(vma->vm_file, prot, vma->vm_flags&VM_SHARED);
}

static int selinux_file_lock(struct file *file, unsigned int cmd)
{
3112 3113 3114
	const struct cred *cred = current_cred();

	return file_has_perm(cred, file, FILE__LOCK);
L
Linus Torvalds 已提交
3115 3116 3117 3118 3119
}

static int selinux_file_fcntl(struct file *file, unsigned int cmd,
			      unsigned long arg)
{
3120
	const struct cred *cred = current_cred();
L
Linus Torvalds 已提交
3121 3122 3123
	int err = 0;

	switch (cmd) {
3124 3125 3126 3127 3128
	case F_SETFL:
		if (!file->f_path.dentry || !file->f_path.dentry->d_inode) {
			err = -EINVAL;
			break;
		}
L
Linus Torvalds 已提交
3129

3130
		if ((file->f_flags & O_APPEND) && !(arg & O_APPEND)) {
3131
			err = file_has_perm(cred, file, FILE__WRITE);
L
Linus Torvalds 已提交
3132
			break;
3133 3134 3135 3136 3137 3138 3139 3140
		}
		/* fall through */
	case F_SETOWN:
	case F_SETSIG:
	case F_GETFL:
	case F_GETOWN:
	case F_GETSIG:
		/* Just check FD__USE permission */
3141
		err = file_has_perm(cred, file, 0);
3142 3143 3144 3145
		break;
	case F_GETLK:
	case F_SETLK:
	case F_SETLKW:
L
Linus Torvalds 已提交
3146
#if BITS_PER_LONG == 32
3147 3148 3149
	case F_GETLK64:
	case F_SETLK64:
	case F_SETLKW64:
L
Linus Torvalds 已提交
3150
#endif
3151 3152
		if (!file->f_path.dentry || !file->f_path.dentry->d_inode) {
			err = -EINVAL;
L
Linus Torvalds 已提交
3153
			break;
3154
		}
3155
		err = file_has_perm(cred, file, FILE__LOCK);
3156
		break;
L
Linus Torvalds 已提交
3157 3158 3159 3160 3161 3162 3163 3164 3165 3166
	}

	return err;
}

static int selinux_file_set_fowner(struct file *file)
{
	struct file_security_struct *fsec;

	fsec = file->f_security;
3167
	fsec->fown_sid = current_sid();
L
Linus Torvalds 已提交
3168 3169 3170 3171 3172 3173 3174

	return 0;
}

static int selinux_file_send_sigiotask(struct task_struct *tsk,
				       struct fown_struct *fown, int signum)
{
3175
	struct file *file;
3176
	u32 sid = current_sid();
L
Linus Torvalds 已提交
3177 3178 3179 3180
	u32 perm;
	struct file_security_struct *fsec;

	/* struct fown_struct is never outside the context of a struct file */
3181
	file = container_of(fown, struct file, f_owner);
L
Linus Torvalds 已提交
3182 3183 3184 3185 3186 3187 3188 3189

	fsec = file->f_security;

	if (!signum)
		perm = signal_to_av(SIGIO); /* as per send_sigio_to_task */
	else
		perm = signal_to_av(signum);

3190
	return avc_has_perm(fsec->fown_sid, sid,
L
Linus Torvalds 已提交
3191 3192 3193 3194 3195
			    SECCLASS_PROCESS, perm, NULL);
}

static int selinux_file_receive(struct file *file)
{
3196 3197 3198
	const struct cred *cred = current_cred();

	return file_has_perm(cred, file, file_to_av(file));
L
Linus Torvalds 已提交
3199 3200
}

3201
static int selinux_dentry_open(struct file *file, const struct cred *cred)
3202 3203 3204 3205
{
	struct file_security_struct *fsec;
	struct inode *inode;
	struct inode_security_struct *isec;
D
David Howells 已提交
3206

3207 3208 3209 3210 3211 3212 3213 3214 3215 3216 3217 3218 3219 3220 3221 3222 3223 3224 3225 3226
	inode = file->f_path.dentry->d_inode;
	fsec = file->f_security;
	isec = inode->i_security;
	/*
	 * Save inode label and policy sequence number
	 * at open-time so that selinux_file_permission
	 * can determine whether revalidation is necessary.
	 * Task label is already saved in the file security
	 * struct as its SID.
	 */
	fsec->isid = isec->sid;
	fsec->pseqno = avc_policy_seqno();
	/*
	 * Since the inode label or policy seqno may have changed
	 * between the selinux_inode_permission check and the saving
	 * of state above, recheck that access is still permitted.
	 * Otherwise, access might never be revalidated against the
	 * new inode label or new policy.
	 * This check is not redundant - do not remove.
	 */
3227
	return inode_has_perm(cred, inode, open_file_to_av(file), NULL);
3228 3229
}

L
Linus Torvalds 已提交
3230 3231 3232 3233 3234 3235 3236 3237 3238 3239
/* task security operations */

static int selinux_task_create(unsigned long clone_flags)
{
	int rc;

	rc = secondary_ops->task_create(clone_flags);
	if (rc)
		return rc;

3240
	return current_has_perm(current, PROCESS__FORK);
L
Linus Torvalds 已提交
3241 3242
}

D
David Howells 已提交
3243 3244 3245 3246
/*
 * detach and free the LSM part of a set of credentials
 */
static void selinux_cred_free(struct cred *cred)
L
Linus Torvalds 已提交
3247
{
D
David Howells 已提交
3248 3249 3250 3251
	struct task_security_struct *tsec = cred->security;
	cred->security = NULL;
	kfree(tsec);
}
L
Linus Torvalds 已提交
3252

D
David Howells 已提交
3253 3254 3255 3256 3257 3258 3259 3260
/*
 * prepare a new set of credentials for modification
 */
static int selinux_cred_prepare(struct cred *new, const struct cred *old,
				gfp_t gfp)
{
	const struct task_security_struct *old_tsec;
	struct task_security_struct *tsec;
L
Linus Torvalds 已提交
3261

D
David Howells 已提交
3262
	old_tsec = old->security;
L
Linus Torvalds 已提交
3263

D
David Howells 已提交
3264 3265 3266
	tsec = kmemdup(old_tsec, sizeof(struct task_security_struct), gfp);
	if (!tsec)
		return -ENOMEM;
L
Linus Torvalds 已提交
3267

D
David Howells 已提交
3268
	new->security = tsec;
L
Linus Torvalds 已提交
3269 3270 3271
	return 0;
}

3272
/*
D
David Howells 已提交
3273
 * commit new credentials
3274
 */
D
David Howells 已提交
3275
static void selinux_cred_commit(struct cred *new, const struct cred *old)
L
Linus Torvalds 已提交
3276
{
D
David Howells 已提交
3277
	secondary_ops->cred_commit(new, old);
L
Linus Torvalds 已提交
3278 3279
}

3280 3281 3282 3283 3284 3285 3286 3287 3288 3289 3290 3291 3292 3293 3294 3295 3296 3297 3298 3299 3300 3301 3302 3303 3304 3305 3306 3307 3308 3309 3310 3311 3312 3313 3314 3315 3316 3317 3318 3319 3320 3321 3322 3323
/*
 * set the security data for a kernel service
 * - all the creation contexts are set to unlabelled
 */
static int selinux_kernel_act_as(struct cred *new, u32 secid)
{
	struct task_security_struct *tsec = new->security;
	u32 sid = current_sid();
	int ret;

	ret = avc_has_perm(sid, secid,
			   SECCLASS_KERNEL_SERVICE,
			   KERNEL_SERVICE__USE_AS_OVERRIDE,
			   NULL);
	if (ret == 0) {
		tsec->sid = secid;
		tsec->create_sid = 0;
		tsec->keycreate_sid = 0;
		tsec->sockcreate_sid = 0;
	}
	return ret;
}

/*
 * set the file creation context in a security record to the same as the
 * objective context of the specified inode
 */
static int selinux_kernel_create_files_as(struct cred *new, struct inode *inode)
{
	struct inode_security_struct *isec = inode->i_security;
	struct task_security_struct *tsec = new->security;
	u32 sid = current_sid();
	int ret;

	ret = avc_has_perm(sid, isec->sid,
			   SECCLASS_KERNEL_SERVICE,
			   KERNEL_SERVICE__CREATE_FILES_AS,
			   NULL);

	if (ret == 0)
		tsec->create_sid = isec->sid;
	return 0;
}

L
Linus Torvalds 已提交
3324 3325 3326 3327 3328 3329 3330 3331 3332 3333 3334
static int selinux_task_setuid(uid_t id0, uid_t id1, uid_t id2, int flags)
{
	/* Since setuid only affects the current process, and
	   since the SELinux controls are not based on the Linux
	   identity attributes, SELinux does not need to control
	   this operation.  However, SELinux does control the use
	   of the CAP_SETUID and CAP_SETGID capabilities using the
	   capable hook. */
	return 0;
}

D
David Howells 已提交
3335 3336
static int selinux_task_fix_setuid(struct cred *new, const struct cred *old,
				   int flags)
L
Linus Torvalds 已提交
3337
{
D
David Howells 已提交
3338
	return secondary_ops->task_fix_setuid(new, old, flags);
L
Linus Torvalds 已提交
3339 3340 3341 3342 3343 3344 3345 3346 3347 3348
}

static int selinux_task_setgid(gid_t id0, gid_t id1, gid_t id2, int flags)
{
	/* See the comment for setuid above. */
	return 0;
}

static int selinux_task_setpgid(struct task_struct *p, pid_t pgid)
{
3349
	return current_has_perm(p, PROCESS__SETPGID);
L
Linus Torvalds 已提交
3350 3351 3352 3353
}

static int selinux_task_getpgid(struct task_struct *p)
{
3354
	return current_has_perm(p, PROCESS__GETPGID);
L
Linus Torvalds 已提交
3355 3356 3357 3358
}

static int selinux_task_getsid(struct task_struct *p)
{
3359
	return current_has_perm(p, PROCESS__GETSESSION);
L
Linus Torvalds 已提交
3360 3361
}

3362 3363
static void selinux_task_getsecid(struct task_struct *p, u32 *secid)
{
3364
	*secid = task_sid(p);
3365 3366
}

L
Linus Torvalds 已提交
3367 3368 3369 3370 3371 3372 3373 3374 3375 3376 3377 3378 3379 3380
static int selinux_task_setgroups(struct group_info *group_info)
{
	/* See the comment for setuid above. */
	return 0;
}

static int selinux_task_setnice(struct task_struct *p, int nice)
{
	int rc;

	rc = secondary_ops->task_setnice(p, nice);
	if (rc)
		return rc;

3381
	return current_has_perm(p, PROCESS__SETSCHED);
L
Linus Torvalds 已提交
3382 3383
}

3384 3385
static int selinux_task_setioprio(struct task_struct *p, int ioprio)
{
3386 3387 3388 3389 3390 3391
	int rc;

	rc = secondary_ops->task_setioprio(p, ioprio);
	if (rc)
		return rc;

3392
	return current_has_perm(p, PROCESS__SETSCHED);
3393 3394
}

3395 3396
static int selinux_task_getioprio(struct task_struct *p)
{
3397
	return current_has_perm(p, PROCESS__GETSCHED);
3398 3399
}

L
Linus Torvalds 已提交
3400 3401 3402 3403 3404 3405 3406 3407 3408 3409 3410 3411
static int selinux_task_setrlimit(unsigned int resource, struct rlimit *new_rlim)
{
	struct rlimit *old_rlim = current->signal->rlim + resource;
	int rc;

	rc = secondary_ops->task_setrlimit(resource, new_rlim);
	if (rc)
		return rc;

	/* Control the ability to change the hard limit (whether
	   lowering or raising it), so that the hard limit can
	   later be used as a safe reset point for the soft limit
D
David Howells 已提交
3412
	   upon context transitions.  See selinux_bprm_committing_creds. */
L
Linus Torvalds 已提交
3413
	if (old_rlim->rlim_max != new_rlim->rlim_max)
3414
		return current_has_perm(current, PROCESS__SETRLIMIT);
L
Linus Torvalds 已提交
3415 3416 3417 3418 3419 3420

	return 0;
}

static int selinux_task_setscheduler(struct task_struct *p, int policy, struct sched_param *lp)
{
3421 3422 3423 3424 3425 3426
	int rc;

	rc = secondary_ops->task_setscheduler(p, policy, lp);
	if (rc)
		return rc;

3427
	return current_has_perm(p, PROCESS__SETSCHED);
L
Linus Torvalds 已提交
3428 3429 3430 3431
}

static int selinux_task_getscheduler(struct task_struct *p)
{
3432
	return current_has_perm(p, PROCESS__GETSCHED);
L
Linus Torvalds 已提交
3433 3434
}

3435 3436
static int selinux_task_movememory(struct task_struct *p)
{
3437
	return current_has_perm(p, PROCESS__SETSCHED);
3438 3439
}

3440 3441
static int selinux_task_kill(struct task_struct *p, struct siginfo *info,
				int sig, u32 secid)
L
Linus Torvalds 已提交
3442 3443 3444 3445
{
	u32 perm;
	int rc;

3446
	rc = secondary_ops->task_kill(p, info, sig, secid);
L
Linus Torvalds 已提交
3447 3448 3449 3450 3451 3452 3453
	if (rc)
		return rc;

	if (!sig)
		perm = PROCESS__SIGNULL; /* null signal; existence test */
	else
		perm = signal_to_av(sig);
3454
	if (secid)
3455 3456
		rc = avc_has_perm(secid, task_sid(p),
				  SECCLASS_PROCESS, perm, NULL);
3457
	else
3458
		rc = current_has_perm(p, perm);
3459
	return rc;
L
Linus Torvalds 已提交
3460 3461 3462 3463 3464 3465
}

static int selinux_task_prctl(int option,
			      unsigned long arg2,
			      unsigned long arg3,
			      unsigned long arg4,
D
David Howells 已提交
3466
			      unsigned long arg5)
L
Linus Torvalds 已提交
3467 3468 3469 3470
{
	/* The current prctl operations do not appear to require
	   any SELinux controls since they merely observe or modify
	   the state of the current process. */
D
David Howells 已提交
3471
	return secondary_ops->task_prctl(option, arg2, arg3, arg4, arg5);
L
Linus Torvalds 已提交
3472 3473 3474 3475
}

static int selinux_task_wait(struct task_struct *p)
{
3476
	return task_has_perm(p, current, PROCESS__SIGCHLD);
L
Linus Torvalds 已提交
3477 3478 3479 3480 3481 3482
}

static void selinux_task_to_inode(struct task_struct *p,
				  struct inode *inode)
{
	struct inode_security_struct *isec = inode->i_security;
3483
	u32 sid = task_sid(p);
L
Linus Torvalds 已提交
3484

3485
	isec->sid = sid;
L
Linus Torvalds 已提交
3486 3487 3488 3489
	isec->initialized = 1;
}

/* Returns error only if unable to parse addresses */
3490 3491
static int selinux_parse_skb_ipv4(struct sk_buff *skb,
			struct avc_audit_data *ad, u8 *proto)
L
Linus Torvalds 已提交
3492 3493 3494 3495
{
	int offset, ihlen, ret = -EINVAL;
	struct iphdr _iph, *ih;

3496
	offset = skb_network_offset(skb);
L
Linus Torvalds 已提交
3497 3498 3499 3500 3501 3502 3503 3504 3505 3506 3507 3508
	ih = skb_header_pointer(skb, offset, sizeof(_iph), &_iph);
	if (ih == NULL)
		goto out;

	ihlen = ih->ihl * 4;
	if (ihlen < sizeof(_iph))
		goto out;

	ad->u.net.v4info.saddr = ih->saddr;
	ad->u.net.v4info.daddr = ih->daddr;
	ret = 0;

3509 3510 3511
	if (proto)
		*proto = ih->protocol;

L
Linus Torvalds 已提交
3512
	switch (ih->protocol) {
3513 3514
	case IPPROTO_TCP: {
		struct tcphdr _tcph, *th;
L
Linus Torvalds 已提交
3515

3516 3517
		if (ntohs(ih->frag_off) & IP_OFFSET)
			break;
L
Linus Torvalds 已提交
3518 3519 3520 3521 3522 3523 3524 3525 3526

		offset += ihlen;
		th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph);
		if (th == NULL)
			break;

		ad->u.net.sport = th->source;
		ad->u.net.dport = th->dest;
		break;
3527 3528 3529 3530 3531 3532 3533 3534
	}

	case IPPROTO_UDP: {
		struct udphdr _udph, *uh;

		if (ntohs(ih->frag_off) & IP_OFFSET)
			break;

L
Linus Torvalds 已提交
3535
		offset += ihlen;
3536
		uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph);
L
Linus Torvalds 已提交
3537
		if (uh == NULL)
3538
			break;
L
Linus Torvalds 已提交
3539

3540 3541 3542 3543
		ad->u.net.sport = uh->source;
		ad->u.net.dport = uh->dest;
		break;
	}
L
Linus Torvalds 已提交
3544

J
James Morris 已提交
3545 3546 3547 3548 3549 3550 3551 3552 3553 3554 3555 3556 3557 3558
	case IPPROTO_DCCP: {
		struct dccp_hdr _dccph, *dh;

		if (ntohs(ih->frag_off) & IP_OFFSET)
			break;

		offset += ihlen;
		dh = skb_header_pointer(skb, offset, sizeof(_dccph), &_dccph);
		if (dh == NULL)
			break;

		ad->u.net.sport = dh->dccph_sport;
		ad->u.net.dport = dh->dccph_dport;
		break;
3559
	}
J
James Morris 已提交
3560

3561 3562 3563
	default:
		break;
	}
L
Linus Torvalds 已提交
3564 3565 3566 3567 3568 3569 3570
out:
	return ret;
}

#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)

/* Returns error only if unable to parse addresses */
3571 3572
static int selinux_parse_skb_ipv6(struct sk_buff *skb,
			struct avc_audit_data *ad, u8 *proto)
L
Linus Torvalds 已提交
3573 3574 3575 3576 3577
{
	u8 nexthdr;
	int ret = -EINVAL, offset;
	struct ipv6hdr _ipv6h, *ip6;

3578
	offset = skb_network_offset(skb);
L
Linus Torvalds 已提交
3579 3580 3581 3582 3583 3584 3585 3586 3587 3588
	ip6 = skb_header_pointer(skb, offset, sizeof(_ipv6h), &_ipv6h);
	if (ip6 == NULL)
		goto out;

	ipv6_addr_copy(&ad->u.net.v6info.saddr, &ip6->saddr);
	ipv6_addr_copy(&ad->u.net.v6info.daddr, &ip6->daddr);
	ret = 0;

	nexthdr = ip6->nexthdr;
	offset += sizeof(_ipv6h);
3589
	offset = ipv6_skip_exthdr(skb, offset, &nexthdr);
L
Linus Torvalds 已提交
3590 3591 3592
	if (offset < 0)
		goto out;

3593 3594 3595
	if (proto)
		*proto = nexthdr;

L
Linus Torvalds 已提交
3596 3597
	switch (nexthdr) {
	case IPPROTO_TCP: {
3598
		struct tcphdr _tcph, *th;
L
Linus Torvalds 已提交
3599 3600 3601 3602 3603 3604 3605 3606 3607 3608 3609 3610 3611 3612 3613 3614 3615 3616 3617 3618 3619 3620

		th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph);
		if (th == NULL)
			break;

		ad->u.net.sport = th->source;
		ad->u.net.dport = th->dest;
		break;
	}

	case IPPROTO_UDP: {
		struct udphdr _udph, *uh;

		uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph);
		if (uh == NULL)
			break;

		ad->u.net.sport = uh->source;
		ad->u.net.dport = uh->dest;
		break;
	}

J
James Morris 已提交
3621 3622 3623 3624 3625 3626 3627 3628 3629 3630
	case IPPROTO_DCCP: {
		struct dccp_hdr _dccph, *dh;

		dh = skb_header_pointer(skb, offset, sizeof(_dccph), &_dccph);
		if (dh == NULL)
			break;

		ad->u.net.sport = dh->dccph_sport;
		ad->u.net.dport = dh->dccph_dport;
		break;
3631
	}
J
James Morris 已提交
3632

L
Linus Torvalds 已提交
3633 3634 3635 3636 3637 3638 3639 3640 3641 3642 3643
	/* includes fragments */
	default:
		break;
	}
out:
	return ret;
}

#endif /* IPV6 */

static int selinux_parse_skb(struct sk_buff *skb, struct avc_audit_data *ad,
3644
			     char **_addrp, int src, u8 *proto)
L
Linus Torvalds 已提交
3645
{
3646 3647
	char *addrp;
	int ret;
L
Linus Torvalds 已提交
3648 3649 3650

	switch (ad->u.net.family) {
	case PF_INET:
3651
		ret = selinux_parse_skb_ipv4(skb, ad, proto);
3652 3653 3654 3655 3656
		if (ret)
			goto parse_error;
		addrp = (char *)(src ? &ad->u.net.v4info.saddr :
				       &ad->u.net.v4info.daddr);
		goto okay;
L
Linus Torvalds 已提交
3657 3658 3659

#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
	case PF_INET6:
3660
		ret = selinux_parse_skb_ipv6(skb, ad, proto);
3661 3662 3663 3664 3665
		if (ret)
			goto parse_error;
		addrp = (char *)(src ? &ad->u.net.v6info.saddr :
				       &ad->u.net.v6info.daddr);
		goto okay;
L
Linus Torvalds 已提交
3666 3667
#endif	/* IPV6 */
	default:
3668 3669
		addrp = NULL;
		goto okay;
L
Linus Torvalds 已提交
3670 3671
	}

3672 3673 3674 3675
parse_error:
	printk(KERN_WARNING
	       "SELinux: failure in selinux_parse_skb(),"
	       " unable to parse packet\n");
L
Linus Torvalds 已提交
3676
	return ret;
3677 3678 3679 3680 3681

okay:
	if (_addrp)
		*_addrp = addrp;
	return 0;
L
Linus Torvalds 已提交
3682 3683
}

3684
/**
3685
 * selinux_skb_peerlbl_sid - Determine the peer label of a packet
3686
 * @skb: the packet
3687
 * @family: protocol family
3688
 * @sid: the packet's peer label SID
3689 3690
 *
 * Description:
3691 3692 3693 3694 3695 3696
 * Check the various different forms of network peer labeling and determine
 * the peer label/SID for the packet; most of the magic actually occurs in
 * the security server function security_net_peersid_cmp().  The function
 * returns zero if the value in @sid is valid (although it may be SECSID_NULL)
 * or -EACCES if @sid is invalid due to inconsistencies with the different
 * peer labels.
3697 3698
 *
 */
3699
static int selinux_skb_peerlbl_sid(struct sk_buff *skb, u16 family, u32 *sid)
3700
{
3701
	int err;
3702 3703
	u32 xfrm_sid;
	u32 nlbl_sid;
3704
	u32 nlbl_type;
3705 3706

	selinux_skb_xfrm_sid(skb, &xfrm_sid);
3707
	selinux_netlbl_skbuff_getsid(skb, family, &nlbl_type, &nlbl_sid);
3708

3709 3710 3711 3712 3713
	err = security_net_peersid_resolve(nlbl_sid, nlbl_type, xfrm_sid, sid);
	if (unlikely(err)) {
		printk(KERN_WARNING
		       "SELinux: failure in selinux_skb_peerlbl_sid(),"
		       " unable to determine packet's peer label\n");
3714
		return -EACCES;
3715
	}
3716 3717

	return 0;
3718 3719
}

L
Linus Torvalds 已提交
3720 3721 3722 3723 3724 3725
/* socket security operations */
static int socket_has_perm(struct task_struct *task, struct socket *sock,
			   u32 perms)
{
	struct inode_security_struct *isec;
	struct avc_audit_data ad;
3726
	u32 sid;
L
Linus Torvalds 已提交
3727 3728 3729 3730 3731 3732
	int err = 0;

	isec = SOCK_INODE(sock)->i_security;

	if (isec->sid == SECINITSID_KERNEL)
		goto out;
3733
	sid = task_sid(task);
L
Linus Torvalds 已提交
3734

3735
	AVC_AUDIT_DATA_INIT(&ad, NET);
L
Linus Torvalds 已提交
3736
	ad.u.net.sk = sock->sk;
3737
	err = avc_has_perm(sid, isec->sid, isec->sclass, perms, &ad);
L
Linus Torvalds 已提交
3738 3739 3740 3741 3742 3743 3744 3745

out:
	return err;
}

static int selinux_socket_create(int family, int type,
				 int protocol, int kern)
{
3746 3747 3748 3749
	const struct cred *cred = current_cred();
	const struct task_security_struct *tsec = cred->security;
	u32 sid, newsid;
	u16 secclass;
L
Linus Torvalds 已提交
3750 3751 3752 3753 3754
	int err = 0;

	if (kern)
		goto out;

3755 3756 3757 3758 3759
	sid = tsec->sid;
	newsid = tsec->sockcreate_sid ?: sid;

	secclass = socket_type_to_security_class(family, type, protocol);
	err = avc_has_perm(sid, newsid, secclass, SOCKET__CREATE, NULL);
L
Linus Torvalds 已提交
3760 3761 3762 3763 3764

out:
	return err;
}

V
Venkat Yekkirala 已提交
3765 3766
static int selinux_socket_post_create(struct socket *sock, int family,
				      int type, int protocol, int kern)
L
Linus Torvalds 已提交
3767
{
3768 3769
	const struct cred *cred = current_cred();
	const struct task_security_struct *tsec = cred->security;
L
Linus Torvalds 已提交
3770
	struct inode_security_struct *isec;
3771
	struct sk_security_struct *sksec;
3772 3773 3774 3775 3776
	u32 sid, newsid;
	int err = 0;

	sid = tsec->sid;
	newsid = tsec->sockcreate_sid;
L
Linus Torvalds 已提交
3777 3778 3779

	isec = SOCK_INODE(sock)->i_security;

3780 3781 3782 3783 3784 3785 3786
	if (kern)
		isec->sid = SECINITSID_KERNEL;
	else if (newsid)
		isec->sid = newsid;
	else
		isec->sid = sid;

L
Linus Torvalds 已提交
3787 3788 3789
	isec->sclass = socket_type_to_security_class(family, type, protocol);
	isec->initialized = 1;

3790 3791 3792
	if (sock->sk) {
		sksec = sock->sk->sk_security;
		sksec->sid = isec->sid;
3793
		sksec->sclass = isec->sclass;
P
Paul Moore 已提交
3794
		err = selinux_netlbl_socket_post_create(sock);
3795 3796
	}

V
Venkat Yekkirala 已提交
3797
	return err;
L
Linus Torvalds 已提交
3798 3799 3800 3801 3802 3803 3804 3805 3806 3807 3808 3809 3810 3811 3812 3813 3814
}

/* Range of port numbers used to automatically bind.
   Need to determine whether we should perform a name_bind
   permission check between the socket and the port number. */

static int selinux_socket_bind(struct socket *sock, struct sockaddr *address, int addrlen)
{
	u16 family;
	int err;

	err = socket_has_perm(current, sock, SOCKET__BIND);
	if (err)
		goto out;

	/*
	 * If PF_INET or PF_INET6, check name_bind permission for the port.
3815 3816
	 * Multiple address binding for SCTP is not supported yet: we just
	 * check the first address now.
L
Linus Torvalds 已提交
3817 3818 3819 3820 3821 3822 3823 3824 3825 3826
	 */
	family = sock->sk->sk_family;
	if (family == PF_INET || family == PF_INET6) {
		char *addrp;
		struct inode_security_struct *isec;
		struct avc_audit_data ad;
		struct sockaddr_in *addr4 = NULL;
		struct sockaddr_in6 *addr6 = NULL;
		unsigned short snum;
		struct sock *sk = sock->sk;
3827
		u32 sid, node_perm;
L
Linus Torvalds 已提交
3828 3829 3830 3831 3832 3833 3834 3835 3836 3837 3838 3839 3840

		isec = SOCK_INODE(sock)->i_security;

		if (family == PF_INET) {
			addr4 = (struct sockaddr_in *)address;
			snum = ntohs(addr4->sin_port);
			addrp = (char *)&addr4->sin_addr.s_addr;
		} else {
			addr6 = (struct sockaddr_in6 *)address;
			snum = ntohs(addr6->sin6_port);
			addrp = (char *)&addr6->sin6_addr.s6_addr;
		}

3841 3842 3843 3844 3845 3846
		if (snum) {
			int low, high;

			inet_get_local_port_range(&low, &high);

			if (snum < max(PROT_SOCK, low) || snum > high) {
P
Paul Moore 已提交
3847 3848
				err = sel_netport_sid(sk->sk_protocol,
						      snum, &sid);
3849 3850
				if (err)
					goto out;
3851
				AVC_AUDIT_DATA_INIT(&ad, NET);
3852 3853 3854 3855 3856 3857 3858 3859
				ad.u.net.sport = htons(snum);
				ad.u.net.family = family;
				err = avc_has_perm(isec->sid, sid,
						   isec->sclass,
						   SOCKET__NAME_BIND, &ad);
				if (err)
					goto out;
			}
L
Linus Torvalds 已提交
3860
		}
3861 3862

		switch (isec->sclass) {
3863
		case SECCLASS_TCP_SOCKET:
L
Linus Torvalds 已提交
3864 3865
			node_perm = TCP_SOCKET__NODE_BIND;
			break;
3866

3867
		case SECCLASS_UDP_SOCKET:
L
Linus Torvalds 已提交
3868 3869
			node_perm = UDP_SOCKET__NODE_BIND;
			break;
J
James Morris 已提交
3870 3871 3872 3873 3874

		case SECCLASS_DCCP_SOCKET:
			node_perm = DCCP_SOCKET__NODE_BIND;
			break;

L
Linus Torvalds 已提交
3875 3876 3877 3878
		default:
			node_perm = RAWIP_SOCKET__NODE_BIND;
			break;
		}
3879

3880
		err = sel_netnode_sid(addrp, family, &sid);
L
Linus Torvalds 已提交
3881 3882
		if (err)
			goto out;
3883 3884

		AVC_AUDIT_DATA_INIT(&ad, NET);
L
Linus Torvalds 已提交
3885 3886 3887 3888 3889 3890 3891 3892 3893
		ad.u.net.sport = htons(snum);
		ad.u.net.family = family;

		if (family == PF_INET)
			ad.u.net.v4info.saddr = addr4->sin_addr.s_addr;
		else
			ipv6_addr_copy(&ad.u.net.v6info.saddr, &addr6->sin6_addr);

		err = avc_has_perm(isec->sid, sid,
3894
				   isec->sclass, node_perm, &ad);
L
Linus Torvalds 已提交
3895 3896 3897 3898 3899 3900 3901 3902 3903
		if (err)
			goto out;
	}
out:
	return err;
}

static int selinux_socket_connect(struct socket *sock, struct sockaddr *address, int addrlen)
{
3904
	struct sock *sk = sock->sk;
L
Linus Torvalds 已提交
3905 3906 3907 3908 3909 3910 3911 3912
	struct inode_security_struct *isec;
	int err;

	err = socket_has_perm(current, sock, SOCKET__CONNECT);
	if (err)
		return err;

	/*
J
James Morris 已提交
3913
	 * If a TCP or DCCP socket, check name_connect permission for the port.
L
Linus Torvalds 已提交
3914 3915
	 */
	isec = SOCK_INODE(sock)->i_security;
J
James Morris 已提交
3916 3917
	if (isec->sclass == SECCLASS_TCP_SOCKET ||
	    isec->sclass == SECCLASS_DCCP_SOCKET) {
L
Linus Torvalds 已提交
3918 3919 3920 3921
		struct avc_audit_data ad;
		struct sockaddr_in *addr4 = NULL;
		struct sockaddr_in6 *addr6 = NULL;
		unsigned short snum;
J
James Morris 已提交
3922
		u32 sid, perm;
L
Linus Torvalds 已提交
3923 3924 3925

		if (sk->sk_family == PF_INET) {
			addr4 = (struct sockaddr_in *)address;
3926
			if (addrlen < sizeof(struct sockaddr_in))
L
Linus Torvalds 已提交
3927 3928 3929 3930
				return -EINVAL;
			snum = ntohs(addr4->sin_port);
		} else {
			addr6 = (struct sockaddr_in6 *)address;
3931
			if (addrlen < SIN6_LEN_RFC2133)
L
Linus Torvalds 已提交
3932 3933 3934 3935
				return -EINVAL;
			snum = ntohs(addr6->sin6_port);
		}

P
Paul Moore 已提交
3936
		err = sel_netport_sid(sk->sk_protocol, snum, &sid);
L
Linus Torvalds 已提交
3937 3938 3939
		if (err)
			goto out;

J
James Morris 已提交
3940 3941 3942
		perm = (isec->sclass == SECCLASS_TCP_SOCKET) ?
		       TCP_SOCKET__NAME_CONNECT : DCCP_SOCKET__NAME_CONNECT;

3943
		AVC_AUDIT_DATA_INIT(&ad, NET);
L
Linus Torvalds 已提交
3944 3945
		ad.u.net.dport = htons(snum);
		ad.u.net.family = sk->sk_family;
J
James Morris 已提交
3946
		err = avc_has_perm(isec->sid, sid, isec->sclass, perm, &ad);
L
Linus Torvalds 已提交
3947 3948 3949 3950
		if (err)
			goto out;
	}

3951 3952
	err = selinux_netlbl_socket_connect(sk, address);

L
Linus Torvalds 已提交
3953 3954 3955 3956 3957 3958 3959 3960 3961 3962 3963 3964 3965 3966 3967 3968 3969 3970 3971 3972 3973 3974 3975 3976 3977 3978 3979 3980 3981 3982
out:
	return err;
}

static int selinux_socket_listen(struct socket *sock, int backlog)
{
	return socket_has_perm(current, sock, SOCKET__LISTEN);
}

static int selinux_socket_accept(struct socket *sock, struct socket *newsock)
{
	int err;
	struct inode_security_struct *isec;
	struct inode_security_struct *newisec;

	err = socket_has_perm(current, sock, SOCKET__ACCEPT);
	if (err)
		return err;

	newisec = SOCK_INODE(newsock)->i_security;

	isec = SOCK_INODE(sock)->i_security;
	newisec->sclass = isec->sclass;
	newisec->sid = isec->sid;
	newisec->initialized = 1;

	return 0;
}

static int selinux_socket_sendmsg(struct socket *sock, struct msghdr *msg,
3983
				  int size)
L
Linus Torvalds 已提交
3984
{
V
Venkat Yekkirala 已提交
3985 3986 3987 3988 3989 3990 3991
	int rc;

	rc = socket_has_perm(current, sock, SOCKET__WRITE);
	if (rc)
		return rc;

	return selinux_netlbl_inode_permission(SOCK_INODE(sock), MAY_WRITE);
L
Linus Torvalds 已提交
3992 3993 3994 3995 3996 3997 3998 3999 4000 4001 4002 4003 4004 4005 4006 4007 4008 4009
}

static int selinux_socket_recvmsg(struct socket *sock, struct msghdr *msg,
				  int size, int flags)
{
	return socket_has_perm(current, sock, SOCKET__READ);
}

static int selinux_socket_getsockname(struct socket *sock)
{
	return socket_has_perm(current, sock, SOCKET__GETATTR);
}

static int selinux_socket_getpeername(struct socket *sock)
{
	return socket_has_perm(current, sock, SOCKET__GETATTR);
}

4010
static int selinux_socket_setsockopt(struct socket *sock, int level, int optname)
L
Linus Torvalds 已提交
4011
{
4012 4013 4014 4015 4016 4017 4018
	int err;

	err = socket_has_perm(current, sock, SOCKET__SETOPT);
	if (err)
		return err;

	return selinux_netlbl_socket_setsockopt(sock, level, optname);
L
Linus Torvalds 已提交
4019 4020 4021 4022 4023 4024 4025 4026 4027 4028 4029 4030 4031 4032 4033 4034 4035 4036 4037 4038 4039 4040 4041 4042 4043 4044 4045 4046 4047 4048
}

static int selinux_socket_getsockopt(struct socket *sock, int level,
				     int optname)
{
	return socket_has_perm(current, sock, SOCKET__GETOPT);
}

static int selinux_socket_shutdown(struct socket *sock, int how)
{
	return socket_has_perm(current, sock, SOCKET__SHUTDOWN);
}

static int selinux_socket_unix_stream_connect(struct socket *sock,
					      struct socket *other,
					      struct sock *newsk)
{
	struct sk_security_struct *ssec;
	struct inode_security_struct *isec;
	struct inode_security_struct *other_isec;
	struct avc_audit_data ad;
	int err;

	err = secondary_ops->unix_stream_connect(sock, other, newsk);
	if (err)
		return err;

	isec = SOCK_INODE(sock)->i_security;
	other_isec = SOCK_INODE(other)->i_security;

4049
	AVC_AUDIT_DATA_INIT(&ad, NET);
L
Linus Torvalds 已提交
4050 4051 4052 4053 4054 4055 4056 4057 4058 4059 4060
	ad.u.net.sk = other->sk;

	err = avc_has_perm(isec->sid, other_isec->sid,
			   isec->sclass,
			   UNIX_STREAM_SOCKET__CONNECTTO, &ad);
	if (err)
		return err;

	/* connecting socket */
	ssec = sock->sk->sk_security;
	ssec->peer_sid = other_isec->sid;
4061

L
Linus Torvalds 已提交
4062 4063 4064
	/* server child socket */
	ssec = newsk->sk_security;
	ssec->peer_sid = isec->sid;
4065 4066 4067
	err = security_sid_mls_copy(other_isec->sid, ssec->peer_sid, &ssec->sid);

	return err;
L
Linus Torvalds 已提交
4068 4069 4070 4071 4072 4073 4074 4075 4076 4077 4078 4079 4080
}

static int selinux_socket_unix_may_send(struct socket *sock,
					struct socket *other)
{
	struct inode_security_struct *isec;
	struct inode_security_struct *other_isec;
	struct avc_audit_data ad;
	int err;

	isec = SOCK_INODE(sock)->i_security;
	other_isec = SOCK_INODE(other)->i_security;

4081
	AVC_AUDIT_DATA_INIT(&ad, NET);
L
Linus Torvalds 已提交
4082 4083 4084 4085 4086 4087 4088 4089 4090 4091
	ad.u.net.sk = other->sk;

	err = avc_has_perm(isec->sid, other_isec->sid,
			   isec->sclass, SOCKET__SENDTO, &ad);
	if (err)
		return err;

	return 0;
}

4092 4093 4094 4095 4096 4097 4098 4099 4100 4101 4102 4103 4104 4105 4106 4107 4108 4109 4110 4111 4112 4113 4114
static int selinux_inet_sys_rcv_skb(int ifindex, char *addrp, u16 family,
				    u32 peer_sid,
				    struct avc_audit_data *ad)
{
	int err;
	u32 if_sid;
	u32 node_sid;

	err = sel_netif_sid(ifindex, &if_sid);
	if (err)
		return err;
	err = avc_has_perm(peer_sid, if_sid,
			   SECCLASS_NETIF, NETIF__INGRESS, ad);
	if (err)
		return err;

	err = sel_netnode_sid(addrp, family, &node_sid);
	if (err)
		return err;
	return avc_has_perm(peer_sid, node_sid,
			    SECCLASS_NODE, NODE__RECVFROM, ad);
}

4115 4116 4117 4118 4119
static int selinux_sock_rcv_skb_iptables_compat(struct sock *sk,
						struct sk_buff *skb,
						struct avc_audit_data *ad,
						u16 family,
						char *addrp)
L
Linus Torvalds 已提交
4120
{
4121 4122 4123 4124 4125
	int err;
	struct sk_security_struct *sksec = sk->sk_security;
	u16 sk_class;
	u32 netif_perm, node_perm, recv_perm;
	u32 port_sid, node_sid, if_sid, sk_sid;
L
Linus Torvalds 已提交
4126

4127 4128
	sk_sid = sksec->sid;
	sk_class = sksec->sclass;
L
Linus Torvalds 已提交
4129

4130
	switch (sk_class) {
L
Linus Torvalds 已提交
4131 4132 4133 4134 4135 4136 4137 4138 4139 4140
	case SECCLASS_UDP_SOCKET:
		netif_perm = NETIF__UDP_RECV;
		node_perm = NODE__UDP_RECV;
		recv_perm = UDP_SOCKET__RECV_MSG;
		break;
	case SECCLASS_TCP_SOCKET:
		netif_perm = NETIF__TCP_RECV;
		node_perm = NODE__TCP_RECV;
		recv_perm = TCP_SOCKET__RECV_MSG;
		break;
J
James Morris 已提交
4141 4142 4143 4144 4145
	case SECCLASS_DCCP_SOCKET:
		netif_perm = NETIF__DCCP_RECV;
		node_perm = NODE__DCCP_RECV;
		recv_perm = DCCP_SOCKET__RECV_MSG;
		break;
L
Linus Torvalds 已提交
4146 4147 4148
	default:
		netif_perm = NETIF__RAWIP_RECV;
		node_perm = NODE__RAWIP_RECV;
4149
		recv_perm = 0;
L
Linus Torvalds 已提交
4150 4151 4152
		break;
	}

4153
	err = sel_netif_sid(skb->iif, &if_sid);
L
Linus Torvalds 已提交
4154
	if (err)
4155 4156 4157 4158
		return err;
	err = avc_has_perm(sk_sid, if_sid, SECCLASS_NETIF, netif_perm, ad);
	if (err)
		return err;
4159

4160
	err = sel_netnode_sid(addrp, family, &node_sid);
L
Linus Torvalds 已提交
4161
	if (err)
4162 4163
		return err;
	err = avc_has_perm(sk_sid, node_sid, SECCLASS_NODE, node_perm, ad);
L
Linus Torvalds 已提交
4164
	if (err)
4165
		return err;
L
Linus Torvalds 已提交
4166

4167 4168
	if (!recv_perm)
		return 0;
P
Paul Moore 已提交
4169 4170
	err = sel_netport_sid(sk->sk_protocol,
			      ntohs(ad->u.net.sport), &port_sid);
4171 4172 4173 4174 4175
	if (unlikely(err)) {
		printk(KERN_WARNING
		       "SELinux: failure in"
		       " selinux_sock_rcv_skb_iptables_compat(),"
		       " network port label not found\n");
4176
		return err;
4177
	}
4178 4179
	return avc_has_perm(sk_sid, port_sid, sk_class, recv_perm, ad);
}
L
Linus Torvalds 已提交
4180

4181
static int selinux_sock_rcv_skb_compat(struct sock *sk, struct sk_buff *skb,
4182
				       u16 family)
4183 4184 4185 4186 4187
{
	int err;
	struct sk_security_struct *sksec = sk->sk_security;
	u32 peer_sid;
	u32 sk_sid = sksec->sid;
4188 4189 4190 4191 4192 4193 4194 4195 4196
	struct avc_audit_data ad;
	char *addrp;

	AVC_AUDIT_DATA_INIT(&ad, NET);
	ad.u.net.netif = skb->iif;
	ad.u.net.family = family;
	err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL);
	if (err)
		return err;
L
Linus Torvalds 已提交
4197

4198
	if (selinux_compat_net)
4199
		err = selinux_sock_rcv_skb_iptables_compat(sk, skb, &ad,
4200 4201 4202
							   family, addrp);
	else
		err = avc_has_perm(sk_sid, skb->secmark, SECCLASS_PACKET,
4203
				   PACKET__RECV, &ad);
4204 4205 4206 4207 4208 4209 4210 4211
	if (err)
		return err;

	if (selinux_policycap_netpeer) {
		err = selinux_skb_peerlbl_sid(skb, family, &peer_sid);
		if (err)
			return err;
		err = avc_has_perm(sk_sid, peer_sid,
4212
				   SECCLASS_PEER, PEER__RECV, &ad);
4213 4214
		if (err)
			selinux_netlbl_err(skb, err, 0);
4215
	} else {
4216
		err = selinux_netlbl_sock_rcv_skb(sksec, skb, family, &ad);
4217 4218
		if (err)
			return err;
4219
		err = selinux_xfrm_sock_rcv_skb(sksec->sid, skb, &ad);
L
Linus Torvalds 已提交
4220
	}
4221

4222 4223 4224 4225 4226
	return err;
}

static int selinux_socket_sock_rcv_skb(struct sock *sk, struct sk_buff *skb)
{
4227
	int err;
4228
	struct sk_security_struct *sksec = sk->sk_security;
4229 4230 4231 4232
	u16 family = sk->sk_family;
	u32 sk_sid = sksec->sid;
	struct avc_audit_data ad;
	char *addrp;
4233 4234
	u8 secmark_active;
	u8 peerlbl_active;
4235 4236

	if (family != PF_INET && family != PF_INET6)
4237
		return 0;
4238 4239

	/* Handle mapped IPv4 packets arriving via IPv6 sockets */
A
Al Viro 已提交
4240
	if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
4241 4242
		family = PF_INET;

4243 4244 4245 4246 4247 4248 4249 4250 4251 4252 4253 4254
	/* If any sort of compatibility mode is enabled then handoff processing
	 * to the selinux_sock_rcv_skb_compat() function to deal with the
	 * special handling.  We do this in an attempt to keep this function
	 * as fast and as clean as possible. */
	if (selinux_compat_net || !selinux_policycap_netpeer)
		return selinux_sock_rcv_skb_compat(sk, skb, family);

	secmark_active = selinux_secmark_enabled();
	peerlbl_active = netlbl_enabled() || selinux_xfrm_enabled();
	if (!secmark_active && !peerlbl_active)
		return 0;

4255
	AVC_AUDIT_DATA_INIT(&ad, NET);
4256
	ad.u.net.netif = skb->iif;
4257
	ad.u.net.family = family;
4258
	err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL);
4259
	if (err)
4260
		return err;
4261

4262
	if (peerlbl_active) {
4263 4264 4265
		u32 peer_sid;

		err = selinux_skb_peerlbl_sid(skb, family, &peer_sid);
4266 4267 4268 4269
		if (err)
			return err;
		err = selinux_inet_sys_rcv_skb(skb->iif, addrp, family,
					       peer_sid, &ad);
4270 4271
		if (err) {
			selinux_netlbl_err(skb, err, 0);
4272
			return err;
4273
		}
4274 4275
		err = avc_has_perm(sk_sid, peer_sid, SECCLASS_PEER,
				   PEER__RECV, &ad);
4276 4277
		if (err)
			selinux_netlbl_err(skb, err, 0);
4278 4279
	}

4280
	if (secmark_active) {
4281 4282 4283 4284 4285 4286
		err = avc_has_perm(sk_sid, skb->secmark, SECCLASS_PACKET,
				   PACKET__RECV, &ad);
		if (err)
			return err;
	}

4287
	return err;
L
Linus Torvalds 已提交
4288 4289
}

C
Catherine Zhang 已提交
4290 4291
static int selinux_socket_getpeersec_stream(struct socket *sock, char __user *optval,
					    int __user *optlen, unsigned len)
L
Linus Torvalds 已提交
4292 4293 4294 4295 4296 4297
{
	int err = 0;
	char *scontext;
	u32 scontext_len;
	struct sk_security_struct *ssec;
	struct inode_security_struct *isec;
4298
	u32 peer_sid = SECSID_NULL;
L
Linus Torvalds 已提交
4299 4300

	isec = SOCK_INODE(sock)->i_security;
C
Catherine Zhang 已提交
4301

4302 4303
	if (isec->sclass == SECCLASS_UNIX_STREAM_SOCKET ||
	    isec->sclass == SECCLASS_TCP_SOCKET) {
C
Catherine Zhang 已提交
4304 4305 4306
		ssec = sock->sk->sk_security;
		peer_sid = ssec->peer_sid;
	}
4307
	if (peer_sid == SECSID_NULL) {
L
Linus Torvalds 已提交
4308 4309 4310 4311
		err = -ENOPROTOOPT;
		goto out;
	}

C
Catherine Zhang 已提交
4312 4313
	err = security_sid_to_context(peer_sid, &scontext, &scontext_len);

L
Linus Torvalds 已提交
4314 4315 4316 4317 4318 4319 4320 4321 4322 4323 4324 4325 4326 4327 4328 4329
	if (err)
		goto out;

	if (scontext_len > len) {
		err = -ERANGE;
		goto out_len;
	}

	if (copy_to_user(optval, scontext, scontext_len))
		err = -EFAULT;

out_len:
	if (put_user(scontext_len, optlen))
		err = -EFAULT;

	kfree(scontext);
4330
out:
L
Linus Torvalds 已提交
4331 4332 4333
	return err;
}

4334
static int selinux_socket_getpeersec_dgram(struct socket *sock, struct sk_buff *skb, u32 *secid)
C
Catherine Zhang 已提交
4335
{
4336
	u32 peer_secid = SECSID_NULL;
4337
	u16 family;
C
Catherine Zhang 已提交
4338

4339 4340 4341 4342 4343
	if (skb && skb->protocol == htons(ETH_P_IP))
		family = PF_INET;
	else if (skb && skb->protocol == htons(ETH_P_IPV6))
		family = PF_INET6;
	else if (sock)
4344 4345 4346 4347 4348
		family = sock->sk->sk_family;
	else
		goto out;

	if (sock && family == PF_UNIX)
4349
		selinux_inode_getsecid(SOCK_INODE(sock), &peer_secid);
4350
	else if (skb)
4351
		selinux_skb_peerlbl_sid(skb, family, &peer_secid);
C
Catherine Zhang 已提交
4352

4353
out:
4354
	*secid = peer_secid;
4355 4356 4357
	if (peer_secid == SECSID_NULL)
		return -EINVAL;
	return 0;
C
Catherine Zhang 已提交
4358 4359
}

A
Al Viro 已提交
4360
static int selinux_sk_alloc_security(struct sock *sk, int family, gfp_t priority)
L
Linus Torvalds 已提交
4361 4362 4363 4364 4365 4366 4367 4368 4369
{
	return sk_alloc_security(sk, family, priority);
}

static void selinux_sk_free_security(struct sock *sk)
{
	sk_free_security(sk);
}

4370
static void selinux_sk_clone_security(const struct sock *sk, struct sock *newsk)
4371
{
4372 4373
	struct sk_security_struct *ssec = sk->sk_security;
	struct sk_security_struct *newssec = newsk->sk_security;
4374

4375 4376
	newssec->sid = ssec->sid;
	newssec->peer_sid = ssec->peer_sid;
4377
	newssec->sclass = ssec->sclass;
4378

4379
	selinux_netlbl_sk_security_reset(newssec, newsk->sk_family);
4380 4381
}

V
Venkat Yekkirala 已提交
4382
static void selinux_sk_getsecid(struct sock *sk, u32 *secid)
4383
{
4384
	if (!sk)
V
Venkat Yekkirala 已提交
4385
		*secid = SECINITSID_ANY_SOCKET;
4386 4387
	else {
		struct sk_security_struct *sksec = sk->sk_security;
4388

V
Venkat Yekkirala 已提交
4389
		*secid = sksec->sid;
4390
	}
4391 4392
}

4393
static void selinux_sock_graft(struct sock *sk, struct socket *parent)
4394 4395 4396 4397
{
	struct inode_security_struct *isec = SOCK_INODE(parent)->i_security;
	struct sk_security_struct *sksec = sk->sk_security;

4398 4399 4400
	if (sk->sk_family == PF_INET || sk->sk_family == PF_INET6 ||
	    sk->sk_family == PF_UNIX)
		isec->sid = sksec->sid;
4401
	sksec->sclass = isec->sclass;
4402 4403
}

4404 4405
static int selinux_inet_conn_request(struct sock *sk, struct sk_buff *skb,
				     struct request_sock *req)
4406 4407 4408
{
	struct sk_security_struct *sksec = sk->sk_security;
	int err;
4409
	u16 family = sk->sk_family;
V
Venkat Yekkirala 已提交
4410
	u32 newsid;
4411 4412
	u32 peersid;

4413 4414 4415 4416 4417
	/* handle mapped IPv4 packets arriving via IPv6 sockets */
	if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
		family = PF_INET;

	err = selinux_skb_peerlbl_sid(skb, family, &peersid);
4418 4419
	if (err)
		return err;
4420 4421
	if (peersid == SECSID_NULL) {
		req->secid = sksec->sid;
4422
		req->peer_secid = SECSID_NULL;
4423 4424 4425
		return 0;
	}

4426 4427 4428 4429 4430
	err = security_sid_mls_copy(sksec->sid, peersid, &newsid);
	if (err)
		return err;

	req->secid = newsid;
4431
	req->peer_secid = peersid;
4432 4433 4434
	return 0;
}

4435 4436
static void selinux_inet_csk_clone(struct sock *newsk,
				   const struct request_sock *req)
4437 4438 4439 4440
{
	struct sk_security_struct *newsksec = newsk->sk_security;

	newsksec->sid = req->secid;
4441
	newsksec->peer_sid = req->peer_secid;
4442 4443 4444 4445
	/* NOTE: Ideally, we should also get the isec->sid for the
	   new socket in sync, but we don't have the isec available yet.
	   So we will wait until sock_graft to do it, by which
	   time it will have been created and available. */
4446

P
Paul Moore 已提交
4447 4448 4449
	/* We don't need to take any sort of lock here as we are the only
	 * thread with access to newsksec */
	selinux_netlbl_sk_security_reset(newsksec, req->rsk_ops->family);
4450 4451
}

4452
static void selinux_inet_conn_established(struct sock *sk, struct sk_buff *skb)
4453
{
4454
	u16 family = sk->sk_family;
4455 4456
	struct sk_security_struct *sksec = sk->sk_security;

4457 4458 4459 4460 4461
	/* handle mapped IPv4 packets arriving via IPv6 sockets */
	if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
		family = PF_INET;

	selinux_skb_peerlbl_sid(skb, family, &sksec->peer_sid);
4462 4463

	selinux_netlbl_inet_conn_established(sk, family);
4464 4465
}

4466 4467
static void selinux_req_classify_flow(const struct request_sock *req,
				      struct flowi *fl)
4468 4469 4470 4471
{
	fl->secid = req->secid;
}

L
Linus Torvalds 已提交
4472 4473 4474 4475 4476 4477 4478
static int selinux_nlmsg_perm(struct sock *sk, struct sk_buff *skb)
{
	int err = 0;
	u32 perm;
	struct nlmsghdr *nlh;
	struct socket *sock = sk->sk_socket;
	struct inode_security_struct *isec = SOCK_INODE(sock)->i_security;
4479

L
Linus Torvalds 已提交
4480 4481 4482 4483
	if (skb->len < NLMSG_SPACE(0)) {
		err = -EINVAL;
		goto out;
	}
4484
	nlh = nlmsg_hdr(skb);
4485

L
Linus Torvalds 已提交
4486 4487 4488
	err = selinux_nlmsg_lookup(isec->sclass, nlh->nlmsg_type, &perm);
	if (err) {
		if (err == -EINVAL) {
4489
			audit_log(current->audit_context, GFP_KERNEL, AUDIT_SELINUX_ERR,
L
Linus Torvalds 已提交
4490 4491 4492
				  "SELinux:  unrecognized netlink message"
				  " type=%hu for sclass=%hu\n",
				  nlh->nlmsg_type, isec->sclass);
4493
			if (!selinux_enforcing || security_get_allow_unknown())
L
Linus Torvalds 已提交
4494 4495 4496 4497 4498 4499 4500 4501 4502 4503 4504 4505 4506 4507 4508 4509
				err = 0;
		}

		/* Ignore */
		if (err == -ENOENT)
			err = 0;
		goto out;
	}

	err = socket_has_perm(current, sock, perm);
out:
	return err;
}

#ifdef CONFIG_NETFILTER

4510 4511
static unsigned int selinux_ip_forward(struct sk_buff *skb, int ifindex,
				       u16 family)
L
Linus Torvalds 已提交
4512
{
4513
	int err;
4514 4515 4516 4517
	char *addrp;
	u32 peer_sid;
	struct avc_audit_data ad;
	u8 secmark_active;
4518
	u8 netlbl_active;
4519
	u8 peerlbl_active;
4520

4521 4522
	if (!selinux_policycap_netpeer)
		return NF_ACCEPT;
4523

4524
	secmark_active = selinux_secmark_enabled();
4525 4526
	netlbl_active = netlbl_enabled();
	peerlbl_active = netlbl_active || selinux_xfrm_enabled();
4527 4528
	if (!secmark_active && !peerlbl_active)
		return NF_ACCEPT;
4529

4530 4531 4532
	if (selinux_skb_peerlbl_sid(skb, family, &peer_sid) != 0)
		return NF_DROP;

4533 4534 4535 4536 4537 4538
	AVC_AUDIT_DATA_INIT(&ad, NET);
	ad.u.net.netif = ifindex;
	ad.u.net.family = family;
	if (selinux_parse_skb(skb, &ad, &addrp, 1, NULL) != 0)
		return NF_DROP;

4539 4540 4541 4542 4543
	if (peerlbl_active) {
		err = selinux_inet_sys_rcv_skb(ifindex, addrp, family,
					       peer_sid, &ad);
		if (err) {
			selinux_netlbl_err(skb, err, 1);
4544
			return NF_DROP;
4545 4546
		}
	}
4547 4548 4549 4550 4551 4552

	if (secmark_active)
		if (avc_has_perm(peer_sid, skb->secmark,
				 SECCLASS_PACKET, PACKET__FORWARD_IN, &ad))
			return NF_DROP;

4553 4554 4555 4556 4557 4558 4559 4560
	if (netlbl_active)
		/* we do this in the FORWARD path and not the POST_ROUTING
		 * path because we want to make sure we apply the necessary
		 * labeling before IPsec is applied so we can leverage AH
		 * protection */
		if (selinux_netlbl_skbuff_setsid(skb, family, peer_sid) != 0)
			return NF_DROP;

4561 4562 4563 4564 4565 4566 4567 4568 4569 4570 4571 4572 4573 4574 4575 4576 4577 4578 4579 4580 4581 4582 4583
	return NF_ACCEPT;
}

static unsigned int selinux_ipv4_forward(unsigned int hooknum,
					 struct sk_buff *skb,
					 const struct net_device *in,
					 const struct net_device *out,
					 int (*okfn)(struct sk_buff *))
{
	return selinux_ip_forward(skb, in->ifindex, PF_INET);
}

#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
static unsigned int selinux_ipv6_forward(unsigned int hooknum,
					 struct sk_buff *skb,
					 const struct net_device *in,
					 const struct net_device *out,
					 int (*okfn)(struct sk_buff *))
{
	return selinux_ip_forward(skb, in->ifindex, PF_INET6);
}
#endif	/* IPV6 */

4584 4585 4586 4587 4588 4589 4590 4591 4592 4593 4594 4595 4596 4597 4598 4599 4600 4601 4602 4603 4604 4605 4606 4607 4608 4609 4610 4611 4612 4613 4614
static unsigned int selinux_ip_output(struct sk_buff *skb,
				      u16 family)
{
	u32 sid;

	if (!netlbl_enabled())
		return NF_ACCEPT;

	/* we do this in the LOCAL_OUT path and not the POST_ROUTING path
	 * because we want to make sure we apply the necessary labeling
	 * before IPsec is applied so we can leverage AH protection */
	if (skb->sk) {
		struct sk_security_struct *sksec = skb->sk->sk_security;
		sid = sksec->sid;
	} else
		sid = SECINITSID_KERNEL;
	if (selinux_netlbl_skbuff_setsid(skb, family, sid) != 0)
		return NF_DROP;

	return NF_ACCEPT;
}

static unsigned int selinux_ipv4_output(unsigned int hooknum,
					struct sk_buff *skb,
					const struct net_device *in,
					const struct net_device *out,
					int (*okfn)(struct sk_buff *))
{
	return selinux_ip_output(skb, PF_INET);
}

4615 4616 4617 4618 4619 4620 4621 4622 4623 4624 4625 4626 4627
static int selinux_ip_postroute_iptables_compat(struct sock *sk,
						int ifindex,
						struct avc_audit_data *ad,
						u16 family, char *addrp)
{
	int err;
	struct sk_security_struct *sksec = sk->sk_security;
	u16 sk_class;
	u32 netif_perm, node_perm, send_perm;
	u32 port_sid, node_sid, if_sid, sk_sid;

	sk_sid = sksec->sid;
	sk_class = sksec->sclass;
L
Linus Torvalds 已提交
4628

4629
	switch (sk_class) {
L
Linus Torvalds 已提交
4630 4631 4632 4633 4634 4635 4636 4637 4638 4639
	case SECCLASS_UDP_SOCKET:
		netif_perm = NETIF__UDP_SEND;
		node_perm = NODE__UDP_SEND;
		send_perm = UDP_SOCKET__SEND_MSG;
		break;
	case SECCLASS_TCP_SOCKET:
		netif_perm = NETIF__TCP_SEND;
		node_perm = NODE__TCP_SEND;
		send_perm = TCP_SOCKET__SEND_MSG;
		break;
J
James Morris 已提交
4640 4641 4642 4643 4644
	case SECCLASS_DCCP_SOCKET:
		netif_perm = NETIF__DCCP_SEND;
		node_perm = NODE__DCCP_SEND;
		send_perm = DCCP_SOCKET__SEND_MSG;
		break;
L
Linus Torvalds 已提交
4645 4646 4647
	default:
		netif_perm = NETIF__RAWIP_SEND;
		node_perm = NODE__RAWIP_SEND;
4648
		send_perm = 0;
L
Linus Torvalds 已提交
4649 4650 4651
		break;
	}

4652
	err = sel_netif_sid(ifindex, &if_sid);
4653
	if (err)
4654 4655 4656
		return err;
	err = avc_has_perm(sk_sid, if_sid, SECCLASS_NETIF, netif_perm, ad);
		return err;
4657

4658
	err = sel_netnode_sid(addrp, family, &node_sid);
4659
	if (err)
4660 4661
		return err;
	err = avc_has_perm(sk_sid, node_sid, SECCLASS_NODE, node_perm, ad);
4662
	if (err)
4663
		return err;
L
Linus Torvalds 已提交
4664

4665 4666 4667
	if (send_perm != 0)
		return 0;

P
Paul Moore 已提交
4668 4669
	err = sel_netport_sid(sk->sk_protocol,
			      ntohs(ad->u.net.dport), &port_sid);
4670 4671 4672 4673 4674
	if (unlikely(err)) {
		printk(KERN_WARNING
		       "SELinux: failure in"
		       " selinux_ip_postroute_iptables_compat(),"
		       " network port label not found\n");
4675
		return err;
4676
	}
4677 4678 4679 4680 4681
	return avc_has_perm(sk_sid, port_sid, sk_class, send_perm, ad);
}

static unsigned int selinux_ip_postroute_compat(struct sk_buff *skb,
						int ifindex,
4682
						u16 family)
4683 4684 4685
{
	struct sock *sk = skb->sk;
	struct sk_security_struct *sksec;
4686 4687 4688
	struct avc_audit_data ad;
	char *addrp;
	u8 proto;
L
Linus Torvalds 已提交
4689

4690 4691 4692 4693
	if (sk == NULL)
		return NF_ACCEPT;
	sksec = sk->sk_security;

4694 4695 4696 4697 4698 4699
	AVC_AUDIT_DATA_INIT(&ad, NET);
	ad.u.net.netif = ifindex;
	ad.u.net.family = family;
	if (selinux_parse_skb(skb, &ad, &addrp, 0, &proto))
		return NF_DROP;

4700 4701
	if (selinux_compat_net) {
		if (selinux_ip_postroute_iptables_compat(skb->sk, ifindex,
4702
							 &ad, family, addrp))
4703 4704 4705
			return NF_DROP;
	} else {
		if (avc_has_perm(sksec->sid, skb->secmark,
4706
				 SECCLASS_PACKET, PACKET__SEND, &ad))
4707
			return NF_DROP;
L
Linus Torvalds 已提交
4708
	}
4709 4710

	if (selinux_policycap_netpeer)
4711
		if (selinux_xfrm_postroute_last(sksec->sid, skb, &ad, proto))
4712 4713 4714
			return NF_DROP;

	return NF_ACCEPT;
4715 4716
}

4717 4718
static unsigned int selinux_ip_postroute(struct sk_buff *skb, int ifindex,
					 u16 family)
4719
{
4720 4721
	u32 secmark_perm;
	u32 peer_sid;
4722 4723
	struct sock *sk;
	struct avc_audit_data ad;
4724 4725 4726
	char *addrp;
	u8 secmark_active;
	u8 peerlbl_active;
4727

4728 4729 4730 4731 4732
	/* If any sort of compatibility mode is enabled then handoff processing
	 * to the selinux_ip_postroute_compat() function to deal with the
	 * special handling.  We do this in an attempt to keep this function
	 * as fast and as clean as possible. */
	if (selinux_compat_net || !selinux_policycap_netpeer)
4733
		return selinux_ip_postroute_compat(skb, ifindex, family);
4734 4735 4736 4737 4738 4739 4740 4741 4742 4743 4744 4745 4746 4747 4748

	/* If skb->dst->xfrm is non-NULL then the packet is undergoing an IPsec
	 * packet transformation so allow the packet to pass without any checks
	 * since we'll have another chance to perform access control checks
	 * when the packet is on it's final way out.
	 * NOTE: there appear to be some IPv6 multicast cases where skb->dst
	 *       is NULL, in this case go ahead and apply access control. */
	if (skb->dst != NULL && skb->dst->xfrm != NULL)
		return NF_ACCEPT;

	secmark_active = selinux_secmark_enabled();
	peerlbl_active = netlbl_enabled() || selinux_xfrm_enabled();
	if (!secmark_active && !peerlbl_active)
		return NF_ACCEPT;

4749 4750 4751 4752
	/* if the packet is being forwarded then get the peer label from the
	 * packet itself; otherwise check to see if it is from a local
	 * application or the kernel, if from an application get the peer label
	 * from the sending socket, otherwise use the kernel's sid */
4753
	sk = skb->sk;
4754 4755 4756 4757 4758 4759 4760 4761 4762 4763 4764 4765 4766 4767 4768 4769 4770 4771 4772 4773 4774 4775 4776
	if (sk == NULL) {
		switch (family) {
		case PF_INET:
			if (IPCB(skb)->flags & IPSKB_FORWARDED)
				secmark_perm = PACKET__FORWARD_OUT;
			else
				secmark_perm = PACKET__SEND;
			break;
		case PF_INET6:
			if (IP6CB(skb)->flags & IP6SKB_FORWARDED)
				secmark_perm = PACKET__FORWARD_OUT;
			else
				secmark_perm = PACKET__SEND;
			break;
		default:
			return NF_DROP;
		}
		if (secmark_perm == PACKET__FORWARD_OUT) {
			if (selinux_skb_peerlbl_sid(skb, family, &peer_sid))
				return NF_DROP;
		} else
			peer_sid = SECINITSID_KERNEL;
	} else {
4777 4778 4779 4780
		struct sk_security_struct *sksec = sk->sk_security;
		peer_sid = sksec->sid;
		secmark_perm = PACKET__SEND;
	}
4781

4782 4783 4784 4785 4786 4787
	AVC_AUDIT_DATA_INIT(&ad, NET);
	ad.u.net.netif = ifindex;
	ad.u.net.family = family;
	if (selinux_parse_skb(skb, &ad, &addrp, 0, NULL))
		return NF_DROP;

4788 4789 4790 4791 4792 4793 4794 4795 4796 4797 4798 4799 4800 4801 4802 4803 4804 4805 4806 4807 4808
	if (secmark_active)
		if (avc_has_perm(peer_sid, skb->secmark,
				 SECCLASS_PACKET, secmark_perm, &ad))
			return NF_DROP;

	if (peerlbl_active) {
		u32 if_sid;
		u32 node_sid;

		if (sel_netif_sid(ifindex, &if_sid))
			return NF_DROP;
		if (avc_has_perm(peer_sid, if_sid,
				 SECCLASS_NETIF, NETIF__EGRESS, &ad))
			return NF_DROP;

		if (sel_netnode_sid(addrp, family, &node_sid))
			return NF_DROP;
		if (avc_has_perm(peer_sid, node_sid,
				 SECCLASS_NODE, NODE__SENDTO, &ad))
			return NF_DROP;
	}
4809

4810
	return NF_ACCEPT;
L
Linus Torvalds 已提交
4811 4812
}

4813 4814 4815 4816 4817
static unsigned int selinux_ipv4_postroute(unsigned int hooknum,
					   struct sk_buff *skb,
					   const struct net_device *in,
					   const struct net_device *out,
					   int (*okfn)(struct sk_buff *))
L
Linus Torvalds 已提交
4818
{
4819
	return selinux_ip_postroute(skb, out->ifindex, PF_INET);
L
Linus Torvalds 已提交
4820 4821 4822
}

#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
4823 4824 4825 4826 4827
static unsigned int selinux_ipv6_postroute(unsigned int hooknum,
					   struct sk_buff *skb,
					   const struct net_device *in,
					   const struct net_device *out,
					   int (*okfn)(struct sk_buff *))
L
Linus Torvalds 已提交
4828
{
4829
	return selinux_ip_postroute(skb, out->ifindex, PF_INET6);
L
Linus Torvalds 已提交
4830 4831 4832 4833 4834 4835 4836 4837 4838 4839 4840 4841 4842 4843 4844 4845 4846 4847 4848
}
#endif	/* IPV6 */

#endif	/* CONFIG_NETFILTER */

static int selinux_netlink_send(struct sock *sk, struct sk_buff *skb)
{
	int err;

	err = secondary_ops->netlink_send(sk, skb);
	if (err)
		return err;

	if (policydb_loaded_version >= POLICYDB_VERSION_NLCLASS)
		err = selinux_nlmsg_perm(sk, skb);

	return err;
}

4849
static int selinux_netlink_recv(struct sk_buff *skb, int capability)
L
Linus Torvalds 已提交
4850
{
4851 4852 4853 4854 4855 4856 4857 4858 4859 4860 4861
	int err;
	struct avc_audit_data ad;

	err = secondary_ops->netlink_recv(skb, capability);
	if (err)
		return err;

	AVC_AUDIT_DATA_INIT(&ad, CAP);
	ad.u.cap = capability;

	return avc_has_perm(NETLINK_CB(skb).sid, NETLINK_CB(skb).sid,
4862
			    SECCLASS_CAPABILITY, CAP_TO_MASK(capability), &ad);
L
Linus Torvalds 已提交
4863 4864 4865 4866 4867 4868 4869
}

static int ipc_alloc_security(struct task_struct *task,
			      struct kern_ipc_perm *perm,
			      u16 sclass)
{
	struct ipc_security_struct *isec;
4870
	u32 sid;
L
Linus Torvalds 已提交
4871

J
James Morris 已提交
4872
	isec = kzalloc(sizeof(struct ipc_security_struct), GFP_KERNEL);
L
Linus Torvalds 已提交
4873 4874 4875
	if (!isec)
		return -ENOMEM;

4876
	sid = task_sid(task);
L
Linus Torvalds 已提交
4877
	isec->sclass = sclass;
4878
	isec->sid = sid;
L
Linus Torvalds 已提交
4879 4880 4881 4882 4883 4884 4885 4886 4887 4888 4889 4890 4891 4892 4893 4894
	perm->security = isec;

	return 0;
}

static void ipc_free_security(struct kern_ipc_perm *perm)
{
	struct ipc_security_struct *isec = perm->security;
	perm->security = NULL;
	kfree(isec);
}

static int msg_msg_alloc_security(struct msg_msg *msg)
{
	struct msg_security_struct *msec;

J
James Morris 已提交
4895
	msec = kzalloc(sizeof(struct msg_security_struct), GFP_KERNEL);
L
Linus Torvalds 已提交
4896 4897 4898 4899 4900 4901 4902 4903 4904 4905 4906 4907 4908 4909 4910 4911 4912 4913
	if (!msec)
		return -ENOMEM;

	msec->sid = SECINITSID_UNLABELED;
	msg->security = msec;

	return 0;
}

static void msg_msg_free_security(struct msg_msg *msg)
{
	struct msg_security_struct *msec = msg->security;

	msg->security = NULL;
	kfree(msec);
}

static int ipc_has_perm(struct kern_ipc_perm *ipc_perms,
4914
			u32 perms)
L
Linus Torvalds 已提交
4915 4916 4917
{
	struct ipc_security_struct *isec;
	struct avc_audit_data ad;
4918
	u32 sid = current_sid();
L
Linus Torvalds 已提交
4919 4920 4921 4922 4923 4924

	isec = ipc_perms->security;

	AVC_AUDIT_DATA_INIT(&ad, IPC);
	ad.u.ipc_id = ipc_perms->key;

4925
	return avc_has_perm(sid, isec->sid, isec->sclass, perms, &ad);
L
Linus Torvalds 已提交
4926 4927 4928 4929 4930 4931 4932 4933 4934 4935 4936 4937 4938 4939 4940 4941 4942
}

static int selinux_msg_msg_alloc_security(struct msg_msg *msg)
{
	return msg_msg_alloc_security(msg);
}

static void selinux_msg_msg_free_security(struct msg_msg *msg)
{
	msg_msg_free_security(msg);
}

/* message queue security operations */
static int selinux_msg_queue_alloc_security(struct msg_queue *msq)
{
	struct ipc_security_struct *isec;
	struct avc_audit_data ad;
4943
	u32 sid = current_sid();
L
Linus Torvalds 已提交
4944 4945 4946 4947 4948 4949 4950 4951 4952
	int rc;

	rc = ipc_alloc_security(current, &msq->q_perm, SECCLASS_MSGQ);
	if (rc)
		return rc;

	isec = msq->q_perm.security;

	AVC_AUDIT_DATA_INIT(&ad, IPC);
4953
	ad.u.ipc_id = msq->q_perm.key;
L
Linus Torvalds 已提交
4954

4955
	rc = avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
L
Linus Torvalds 已提交
4956 4957 4958 4959 4960 4961 4962 4963 4964 4965 4966 4967 4968 4969 4970 4971 4972
			  MSGQ__CREATE, &ad);
	if (rc) {
		ipc_free_security(&msq->q_perm);
		return rc;
	}
	return 0;
}

static void selinux_msg_queue_free_security(struct msg_queue *msq)
{
	ipc_free_security(&msq->q_perm);
}

static int selinux_msg_queue_associate(struct msg_queue *msq, int msqflg)
{
	struct ipc_security_struct *isec;
	struct avc_audit_data ad;
4973
	u32 sid = current_sid();
L
Linus Torvalds 已提交
4974 4975 4976 4977 4978 4979

	isec = msq->q_perm.security;

	AVC_AUDIT_DATA_INIT(&ad, IPC);
	ad.u.ipc_id = msq->q_perm.key;

4980
	return avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
L
Linus Torvalds 已提交
4981 4982 4983 4984 4985 4986 4987 4988
			    MSGQ__ASSOCIATE, &ad);
}

static int selinux_msg_queue_msgctl(struct msg_queue *msq, int cmd)
{
	int err;
	int perms;

4989
	switch (cmd) {
L
Linus Torvalds 已提交
4990 4991 4992 4993 4994 4995 4996 4997 4998 4999 5000 5001 5002 5003 5004 5005 5006 5007
	case IPC_INFO:
	case MSG_INFO:
		/* No specific object, just general system-wide information. */
		return task_has_system(current, SYSTEM__IPC_INFO);
	case IPC_STAT:
	case MSG_STAT:
		perms = MSGQ__GETATTR | MSGQ__ASSOCIATE;
		break;
	case IPC_SET:
		perms = MSGQ__SETATTR;
		break;
	case IPC_RMID:
		perms = MSGQ__DESTROY;
		break;
	default:
		return 0;
	}

5008
	err = ipc_has_perm(&msq->q_perm, perms);
L
Linus Torvalds 已提交
5009 5010 5011 5012 5013 5014 5015 5016
	return err;
}

static int selinux_msg_queue_msgsnd(struct msg_queue *msq, struct msg_msg *msg, int msqflg)
{
	struct ipc_security_struct *isec;
	struct msg_security_struct *msec;
	struct avc_audit_data ad;
5017
	u32 sid = current_sid();
L
Linus Torvalds 已提交
5018 5019 5020 5021 5022 5023 5024 5025 5026 5027 5028 5029 5030
	int rc;

	isec = msq->q_perm.security;
	msec = msg->security;

	/*
	 * First time through, need to assign label to the message
	 */
	if (msec->sid == SECINITSID_UNLABELED) {
		/*
		 * Compute new sid based on current process and
		 * message queue this message will be stored in
		 */
5031
		rc = security_transition_sid(sid, isec->sid, SECCLASS_MSG,
L
Linus Torvalds 已提交
5032 5033 5034 5035 5036 5037 5038 5039 5040
					     &msec->sid);
		if (rc)
			return rc;
	}

	AVC_AUDIT_DATA_INIT(&ad, IPC);
	ad.u.ipc_id = msq->q_perm.key;

	/* Can this process write to the queue? */
5041
	rc = avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
L
Linus Torvalds 已提交
5042 5043 5044
			  MSGQ__WRITE, &ad);
	if (!rc)
		/* Can this process send the message */
5045 5046
		rc = avc_has_perm(sid, msec->sid, SECCLASS_MSG,
				  MSG__SEND, &ad);
L
Linus Torvalds 已提交
5047 5048
	if (!rc)
		/* Can the message be put in the queue? */
5049 5050
		rc = avc_has_perm(msec->sid, isec->sid, SECCLASS_MSGQ,
				  MSGQ__ENQUEUE, &ad);
L
Linus Torvalds 已提交
5051 5052 5053 5054 5055 5056 5057 5058 5059 5060 5061

	return rc;
}

static int selinux_msg_queue_msgrcv(struct msg_queue *msq, struct msg_msg *msg,
				    struct task_struct *target,
				    long type, int mode)
{
	struct ipc_security_struct *isec;
	struct msg_security_struct *msec;
	struct avc_audit_data ad;
5062
	u32 sid = task_sid(target);
L
Linus Torvalds 已提交
5063 5064 5065 5066 5067 5068
	int rc;

	isec = msq->q_perm.security;
	msec = msg->security;

	AVC_AUDIT_DATA_INIT(&ad, IPC);
5069
	ad.u.ipc_id = msq->q_perm.key;
L
Linus Torvalds 已提交
5070

5071
	rc = avc_has_perm(sid, isec->sid,
L
Linus Torvalds 已提交
5072 5073
			  SECCLASS_MSGQ, MSGQ__READ, &ad);
	if (!rc)
5074
		rc = avc_has_perm(sid, msec->sid,
L
Linus Torvalds 已提交
5075 5076 5077 5078 5079 5080 5081 5082 5083
				  SECCLASS_MSG, MSG__RECEIVE, &ad);
	return rc;
}

/* Shared Memory security operations */
static int selinux_shm_alloc_security(struct shmid_kernel *shp)
{
	struct ipc_security_struct *isec;
	struct avc_audit_data ad;
5084
	u32 sid = current_sid();
L
Linus Torvalds 已提交
5085 5086 5087 5088 5089 5090 5091 5092 5093
	int rc;

	rc = ipc_alloc_security(current, &shp->shm_perm, SECCLASS_SHM);
	if (rc)
		return rc;

	isec = shp->shm_perm.security;

	AVC_AUDIT_DATA_INIT(&ad, IPC);
5094
	ad.u.ipc_id = shp->shm_perm.key;
L
Linus Torvalds 已提交
5095

5096
	rc = avc_has_perm(sid, isec->sid, SECCLASS_SHM,
L
Linus Torvalds 已提交
5097 5098 5099 5100 5101 5102 5103 5104 5105 5106 5107 5108 5109 5110 5111 5112 5113
			  SHM__CREATE, &ad);
	if (rc) {
		ipc_free_security(&shp->shm_perm);
		return rc;
	}
	return 0;
}

static void selinux_shm_free_security(struct shmid_kernel *shp)
{
	ipc_free_security(&shp->shm_perm);
}

static int selinux_shm_associate(struct shmid_kernel *shp, int shmflg)
{
	struct ipc_security_struct *isec;
	struct avc_audit_data ad;
5114
	u32 sid = current_sid();
L
Linus Torvalds 已提交
5115 5116 5117 5118 5119 5120

	isec = shp->shm_perm.security;

	AVC_AUDIT_DATA_INIT(&ad, IPC);
	ad.u.ipc_id = shp->shm_perm.key;

5121
	return avc_has_perm(sid, isec->sid, SECCLASS_SHM,
L
Linus Torvalds 已提交
5122 5123 5124 5125 5126 5127 5128 5129 5130
			    SHM__ASSOCIATE, &ad);
}

/* Note, at this point, shp is locked down */
static int selinux_shm_shmctl(struct shmid_kernel *shp, int cmd)
{
	int perms;
	int err;

5131
	switch (cmd) {
L
Linus Torvalds 已提交
5132 5133 5134 5135 5136 5137 5138 5139 5140 5141 5142 5143 5144 5145 5146 5147 5148 5149 5150 5151 5152 5153
	case IPC_INFO:
	case SHM_INFO:
		/* No specific object, just general system-wide information. */
		return task_has_system(current, SYSTEM__IPC_INFO);
	case IPC_STAT:
	case SHM_STAT:
		perms = SHM__GETATTR | SHM__ASSOCIATE;
		break;
	case IPC_SET:
		perms = SHM__SETATTR;
		break;
	case SHM_LOCK:
	case SHM_UNLOCK:
		perms = SHM__LOCK;
		break;
	case IPC_RMID:
		perms = SHM__DESTROY;
		break;
	default:
		return 0;
	}

5154
	err = ipc_has_perm(&shp->shm_perm, perms);
L
Linus Torvalds 已提交
5155 5156 5157 5158 5159 5160 5161 5162 5163 5164 5165 5166 5167 5168 5169 5170 5171 5172
	return err;
}

static int selinux_shm_shmat(struct shmid_kernel *shp,
			     char __user *shmaddr, int shmflg)
{
	u32 perms;
	int rc;

	rc = secondary_ops->shm_shmat(shp, shmaddr, shmflg);
	if (rc)
		return rc;

	if (shmflg & SHM_RDONLY)
		perms = SHM__READ;
	else
		perms = SHM__READ | SHM__WRITE;

5173
	return ipc_has_perm(&shp->shm_perm, perms);
L
Linus Torvalds 已提交
5174 5175 5176 5177 5178 5179 5180
}

/* Semaphore security operations */
static int selinux_sem_alloc_security(struct sem_array *sma)
{
	struct ipc_security_struct *isec;
	struct avc_audit_data ad;
5181
	u32 sid = current_sid();
L
Linus Torvalds 已提交
5182 5183 5184 5185 5186 5187 5188 5189 5190
	int rc;

	rc = ipc_alloc_security(current, &sma->sem_perm, SECCLASS_SEM);
	if (rc)
		return rc;

	isec = sma->sem_perm.security;

	AVC_AUDIT_DATA_INIT(&ad, IPC);
5191
	ad.u.ipc_id = sma->sem_perm.key;
L
Linus Torvalds 已提交
5192

5193
	rc = avc_has_perm(sid, isec->sid, SECCLASS_SEM,
L
Linus Torvalds 已提交
5194 5195 5196 5197 5198 5199 5200 5201 5202 5203 5204 5205 5206 5207 5208 5209 5210
			  SEM__CREATE, &ad);
	if (rc) {
		ipc_free_security(&sma->sem_perm);
		return rc;
	}
	return 0;
}

static void selinux_sem_free_security(struct sem_array *sma)
{
	ipc_free_security(&sma->sem_perm);
}

static int selinux_sem_associate(struct sem_array *sma, int semflg)
{
	struct ipc_security_struct *isec;
	struct avc_audit_data ad;
5211
	u32 sid = current_sid();
L
Linus Torvalds 已提交
5212 5213 5214 5215 5216 5217

	isec = sma->sem_perm.security;

	AVC_AUDIT_DATA_INIT(&ad, IPC);
	ad.u.ipc_id = sma->sem_perm.key;

5218
	return avc_has_perm(sid, isec->sid, SECCLASS_SEM,
L
Linus Torvalds 已提交
5219 5220 5221 5222 5223 5224 5225 5226 5227
			    SEM__ASSOCIATE, &ad);
}

/* Note, at this point, sma is locked down */
static int selinux_sem_semctl(struct sem_array *sma, int cmd)
{
	int err;
	u32 perms;

5228
	switch (cmd) {
L
Linus Torvalds 已提交
5229 5230 5231 5232 5233 5234 5235 5236 5237 5238 5239 5240 5241 5242 5243 5244 5245 5246 5247 5248 5249 5250 5251 5252 5253 5254 5255 5256 5257 5258 5259
	case IPC_INFO:
	case SEM_INFO:
		/* No specific object, just general system-wide information. */
		return task_has_system(current, SYSTEM__IPC_INFO);
	case GETPID:
	case GETNCNT:
	case GETZCNT:
		perms = SEM__GETATTR;
		break;
	case GETVAL:
	case GETALL:
		perms = SEM__READ;
		break;
	case SETVAL:
	case SETALL:
		perms = SEM__WRITE;
		break;
	case IPC_RMID:
		perms = SEM__DESTROY;
		break;
	case IPC_SET:
		perms = SEM__SETATTR;
		break;
	case IPC_STAT:
	case SEM_STAT:
		perms = SEM__GETATTR | SEM__ASSOCIATE;
		break;
	default:
		return 0;
	}

5260
	err = ipc_has_perm(&sma->sem_perm, perms);
L
Linus Torvalds 已提交
5261 5262 5263 5264 5265 5266 5267 5268 5269 5270 5271 5272 5273
	return err;
}

static int selinux_sem_semop(struct sem_array *sma,
			     struct sembuf *sops, unsigned nsops, int alter)
{
	u32 perms;

	if (alter)
		perms = SEM__READ | SEM__WRITE;
	else
		perms = SEM__READ;

5274
	return ipc_has_perm(&sma->sem_perm, perms);
L
Linus Torvalds 已提交
5275 5276 5277 5278 5279 5280 5281 5282 5283 5284 5285 5286 5287 5288 5289
}

static int selinux_ipc_permission(struct kern_ipc_perm *ipcp, short flag)
{
	u32 av = 0;

	av = 0;
	if (flag & S_IRUGO)
		av |= IPC__UNIX_READ;
	if (flag & S_IWUGO)
		av |= IPC__UNIX_WRITE;

	if (av == 0)
		return 0;

5290
	return ipc_has_perm(ipcp, av);
L
Linus Torvalds 已提交
5291 5292
}

5293 5294 5295 5296 5297 5298
static void selinux_ipc_getsecid(struct kern_ipc_perm *ipcp, u32 *secid)
{
	struct ipc_security_struct *isec = ipcp->security;
	*secid = isec->sid;
}

5299
static void selinux_d_instantiate(struct dentry *dentry, struct inode *inode)
L
Linus Torvalds 已提交
5300 5301 5302 5303 5304 5305
{
	if (inode)
		inode_doinit_with_dentry(inode, dentry);
}

static int selinux_getprocattr(struct task_struct *p,
5306
			       char *name, char **value)
L
Linus Torvalds 已提交
5307
{
5308
	const struct task_security_struct *__tsec;
5309
	u32 sid;
L
Linus Torvalds 已提交
5310
	int error;
5311
	unsigned len;
L
Linus Torvalds 已提交
5312 5313

	if (current != p) {
5314
		error = current_has_perm(p, PROCESS__GETATTR);
L
Linus Torvalds 已提交
5315 5316 5317 5318
		if (error)
			return error;
	}

5319 5320
	rcu_read_lock();
	__tsec = __task_cred(p)->security;
L
Linus Torvalds 已提交
5321 5322

	if (!strcmp(name, "current"))
5323
		sid = __tsec->sid;
L
Linus Torvalds 已提交
5324
	else if (!strcmp(name, "prev"))
5325
		sid = __tsec->osid;
L
Linus Torvalds 已提交
5326
	else if (!strcmp(name, "exec"))
5327
		sid = __tsec->exec_sid;
L
Linus Torvalds 已提交
5328
	else if (!strcmp(name, "fscreate"))
5329
		sid = __tsec->create_sid;
5330
	else if (!strcmp(name, "keycreate"))
5331
		sid = __tsec->keycreate_sid;
5332
	else if (!strcmp(name, "sockcreate"))
5333
		sid = __tsec->sockcreate_sid;
L
Linus Torvalds 已提交
5334
	else
5335 5336
		goto invalid;
	rcu_read_unlock();
L
Linus Torvalds 已提交
5337 5338 5339 5340

	if (!sid)
		return 0;

5341 5342 5343 5344
	error = security_sid_to_context(sid, value, &len);
	if (error)
		return error;
	return len;
5345 5346 5347 5348

invalid:
	rcu_read_unlock();
	return -EINVAL;
L
Linus Torvalds 已提交
5349 5350 5351 5352 5353 5354
}

static int selinux_setprocattr(struct task_struct *p,
			       char *name, void *value, size_t size)
{
	struct task_security_struct *tsec;
R
Roland McGrath 已提交
5355
	struct task_struct *tracer;
D
David Howells 已提交
5356 5357
	struct cred *new;
	u32 sid = 0, ptsid;
L
Linus Torvalds 已提交
5358 5359 5360 5361 5362 5363 5364 5365 5366 5367 5368 5369 5370 5371 5372
	int error;
	char *str = value;

	if (current != p) {
		/* SELinux only allows a process to change its own
		   security attributes. */
		return -EACCES;
	}

	/*
	 * Basic control over ability to set these attributes at all.
	 * current == p, but we'll pass them separately in case the
	 * above restriction is ever removed.
	 */
	if (!strcmp(name, "exec"))
5373
		error = current_has_perm(p, PROCESS__SETEXEC);
L
Linus Torvalds 已提交
5374
	else if (!strcmp(name, "fscreate"))
5375
		error = current_has_perm(p, PROCESS__SETFSCREATE);
5376
	else if (!strcmp(name, "keycreate"))
5377
		error = current_has_perm(p, PROCESS__SETKEYCREATE);
5378
	else if (!strcmp(name, "sockcreate"))
5379
		error = current_has_perm(p, PROCESS__SETSOCKCREATE);
L
Linus Torvalds 已提交
5380
	else if (!strcmp(name, "current"))
5381
		error = current_has_perm(p, PROCESS__SETCURRENT);
L
Linus Torvalds 已提交
5382 5383 5384 5385 5386 5387 5388 5389 5390 5391 5392 5393
	else
		error = -EINVAL;
	if (error)
		return error;

	/* Obtain a SID for the context, if one was specified. */
	if (size && str[1] && str[1] != '\n') {
		if (str[size-1] == '\n') {
			str[size-1] = 0;
			size--;
		}
		error = security_context_to_sid(value, size, &sid);
5394 5395 5396 5397 5398 5399
		if (error == -EINVAL && !strcmp(name, "fscreate")) {
			if (!capable(CAP_MAC_ADMIN))
				return error;
			error = security_context_to_sid_force(value, size,
							      &sid);
		}
L
Linus Torvalds 已提交
5400 5401 5402 5403
		if (error)
			return error;
	}

D
David Howells 已提交
5404 5405 5406 5407
	new = prepare_creds();
	if (!new)
		return -ENOMEM;

L
Linus Torvalds 已提交
5408 5409 5410
	/* Permission checking based on the specified context is
	   performed during the actual operation (execve,
	   open/mkdir/...), when we know the full context of the
D
David Howells 已提交
5411
	   operation.  See selinux_bprm_set_creds for the execve
L
Linus Torvalds 已提交
5412 5413
	   checks and may_create for the file creation checks. The
	   operation will then fail if the context is not permitted. */
D
David Howells 已提交
5414 5415
	tsec = new->security;
	if (!strcmp(name, "exec")) {
L
Linus Torvalds 已提交
5416
		tsec->exec_sid = sid;
D
David Howells 已提交
5417
	} else if (!strcmp(name, "fscreate")) {
L
Linus Torvalds 已提交
5418
		tsec->create_sid = sid;
D
David Howells 已提交
5419
	} else if (!strcmp(name, "keycreate")) {
5420 5421
		error = may_create_key(sid, p);
		if (error)
D
David Howells 已提交
5422
			goto abort_change;
5423
		tsec->keycreate_sid = sid;
D
David Howells 已提交
5424
	} else if (!strcmp(name, "sockcreate")) {
5425
		tsec->sockcreate_sid = sid;
D
David Howells 已提交
5426 5427
	} else if (!strcmp(name, "current")) {
		error = -EINVAL;
L
Linus Torvalds 已提交
5428
		if (sid == 0)
D
David Howells 已提交
5429 5430 5431 5432 5433 5434 5435 5436
			goto abort_change;

		/* Only allow single threaded processes to change context */
		error = -EPERM;
		if (!is_single_threaded(p)) {
			error = security_bounded_transition(tsec->sid, sid);
			if (error)
				goto abort_change;
5437
		}
L
Linus Torvalds 已提交
5438 5439 5440

		/* Check permissions for the transition. */
		error = avc_has_perm(tsec->sid, sid, SECCLASS_PROCESS,
5441
				     PROCESS__DYNTRANSITION, NULL);
L
Linus Torvalds 已提交
5442
		if (error)
D
David Howells 已提交
5443
			goto abort_change;
L
Linus Torvalds 已提交
5444 5445 5446

		/* Check for ptracing, and update the task SID if ok.
		   Otherwise, leave SID unchanged and fail. */
D
David Howells 已提交
5447
		ptsid = 0;
L
Linus Torvalds 已提交
5448
		task_lock(p);
5449
		tracer = tracehook_tracer_task(p);
D
David Howells 已提交
5450 5451 5452 5453 5454 5455 5456
		if (tracer)
			ptsid = task_sid(tracer);
		task_unlock(p);

		if (tracer) {
			error = avc_has_perm(ptsid, sid, SECCLASS_PROCESS,
					     PROCESS__PTRACE, NULL);
L
Linus Torvalds 已提交
5457
			if (error)
D
David Howells 已提交
5458
				goto abort_change;
L
Linus Torvalds 已提交
5459 5460
		}

D
David Howells 已提交
5461 5462 5463 5464 5465 5466 5467
		tsec->sid = sid;
	} else {
		error = -EINVAL;
		goto abort_change;
	}

	commit_creds(new);
L
Linus Torvalds 已提交
5468
	return size;
D
David Howells 已提交
5469 5470 5471 5472

abort_change:
	abort_creds(new);
	return error;
L
Linus Torvalds 已提交
5473 5474
}

5475 5476 5477 5478 5479
static int selinux_secid_to_secctx(u32 secid, char **secdata, u32 *seclen)
{
	return security_sid_to_context(secid, secdata, seclen);
}

5480
static int selinux_secctx_to_secid(const char *secdata, u32 seclen, u32 *secid)
5481 5482 5483 5484
{
	return security_context_to_sid(secdata, seclen, secid);
}

5485 5486
static void selinux_release_secctx(char *secdata, u32 seclen)
{
5487
	kfree(secdata);
5488 5489
}

5490 5491
#ifdef CONFIG_KEYS

D
David Howells 已提交
5492
static int selinux_key_alloc(struct key *k, const struct cred *cred,
5493
			     unsigned long flags)
5494
{
D
David Howells 已提交
5495
	const struct task_security_struct *tsec;
5496 5497 5498 5499 5500 5501
	struct key_security_struct *ksec;

	ksec = kzalloc(sizeof(struct key_security_struct), GFP_KERNEL);
	if (!ksec)
		return -ENOMEM;

D
David Howells 已提交
5502 5503 5504
	tsec = cred->security;
	if (tsec->keycreate_sid)
		ksec->sid = tsec->keycreate_sid;
5505
	else
D
David Howells 已提交
5506
		ksec->sid = tsec->sid;
5507

5508
	k->security = ksec;
5509 5510 5511 5512 5513 5514 5515 5516 5517 5518 5519 5520
	return 0;
}

static void selinux_key_free(struct key *k)
{
	struct key_security_struct *ksec = k->security;

	k->security = NULL;
	kfree(ksec);
}

static int selinux_key_permission(key_ref_t key_ref,
D
David Howells 已提交
5521 5522
				  const struct cred *cred,
				  key_perm_t perm)
5523 5524 5525
{
	struct key *key;
	struct key_security_struct *ksec;
5526
	u32 sid;
5527 5528 5529 5530 5531 5532 5533

	/* if no specific permissions are requested, we skip the
	   permission check. No serious, additional covert channels
	   appear to be created. */
	if (perm == 0)
		return 0;

D
David Howells 已提交
5534
	sid = cred_sid(cred);
5535 5536 5537 5538 5539

	key = key_ref_to_ptr(key_ref);
	ksec = key->security;

	return avc_has_perm(sid, ksec->sid, SECCLASS_KEY, perm, NULL);
5540 5541
}

5542 5543 5544 5545 5546 5547 5548 5549 5550 5551 5552 5553 5554 5555
static int selinux_key_getsecurity(struct key *key, char **_buffer)
{
	struct key_security_struct *ksec = key->security;
	char *context = NULL;
	unsigned len;
	int rc;

	rc = security_sid_to_context(ksec->sid, &context, &len);
	if (!rc)
		rc = len;
	*_buffer = context;
	return rc;
}

5556 5557
#endif

L
Linus Torvalds 已提交
5558
static struct security_operations selinux_ops = {
5559 5560
	.name =				"selinux",

5561 5562
	.ptrace_may_access =		selinux_ptrace_may_access,
	.ptrace_traceme =		selinux_ptrace_traceme,
L
Linus Torvalds 已提交
5563
	.capget =			selinux_capget,
D
David Howells 已提交
5564
	.capset =			selinux_capset,
L
Linus Torvalds 已提交
5565 5566 5567 5568 5569 5570 5571 5572
	.sysctl =			selinux_sysctl,
	.capable =			selinux_capable,
	.quotactl =			selinux_quotactl,
	.quota_on =			selinux_quota_on,
	.syslog =			selinux_syslog,
	.vm_enough_memory =		selinux_vm_enough_memory,

	.netlink_send =			selinux_netlink_send,
5573
	.netlink_recv =			selinux_netlink_recv,
L
Linus Torvalds 已提交
5574

5575
	.bprm_set_creds =		selinux_bprm_set_creds,
L
Linus Torvalds 已提交
5576
	.bprm_check_security =		selinux_bprm_check_security,
5577 5578
	.bprm_committing_creds =	selinux_bprm_committing_creds,
	.bprm_committed_creds =		selinux_bprm_committed_creds,
L
Linus Torvalds 已提交
5579 5580 5581 5582 5583
	.bprm_secureexec =		selinux_bprm_secureexec,

	.sb_alloc_security =		selinux_sb_alloc_security,
	.sb_free_security =		selinux_sb_free_security,
	.sb_copy_data =			selinux_sb_copy_data,
5584
	.sb_kern_mount =		selinux_sb_kern_mount,
5585
	.sb_show_options =		selinux_sb_show_options,
L
Linus Torvalds 已提交
5586 5587 5588
	.sb_statfs =			selinux_sb_statfs,
	.sb_mount =			selinux_mount,
	.sb_umount =			selinux_umount,
5589
	.sb_set_mnt_opts =		selinux_set_mnt_opts,
5590
	.sb_clone_mnt_opts =		selinux_sb_clone_mnt_opts,
5591 5592
	.sb_parse_opts_str = 		selinux_parse_opts_str,

L
Linus Torvalds 已提交
5593 5594 5595

	.inode_alloc_security =		selinux_inode_alloc_security,
	.inode_free_security =		selinux_inode_free_security,
5596
	.inode_init_security =		selinux_inode_init_security,
L
Linus Torvalds 已提交
5597 5598 5599 5600 5601 5602 5603 5604 5605 5606 5607 5608 5609 5610 5611 5612 5613 5614
	.inode_create =			selinux_inode_create,
	.inode_link =			selinux_inode_link,
	.inode_unlink =			selinux_inode_unlink,
	.inode_symlink =		selinux_inode_symlink,
	.inode_mkdir =			selinux_inode_mkdir,
	.inode_rmdir =			selinux_inode_rmdir,
	.inode_mknod =			selinux_inode_mknod,
	.inode_rename =			selinux_inode_rename,
	.inode_readlink =		selinux_inode_readlink,
	.inode_follow_link =		selinux_inode_follow_link,
	.inode_permission =		selinux_inode_permission,
	.inode_setattr =		selinux_inode_setattr,
	.inode_getattr =		selinux_inode_getattr,
	.inode_setxattr =		selinux_inode_setxattr,
	.inode_post_setxattr =		selinux_inode_post_setxattr,
	.inode_getxattr =		selinux_inode_getxattr,
	.inode_listxattr =		selinux_inode_listxattr,
	.inode_removexattr =		selinux_inode_removexattr,
5615 5616 5617
	.inode_getsecurity =		selinux_inode_getsecurity,
	.inode_setsecurity =		selinux_inode_setsecurity,
	.inode_listsecurity =		selinux_inode_listsecurity,
5618 5619
	.inode_need_killpriv =		selinux_inode_need_killpriv,
	.inode_killpriv =		selinux_inode_killpriv,
5620
	.inode_getsecid =		selinux_inode_getsecid,
L
Linus Torvalds 已提交
5621 5622 5623 5624 5625 5626 5627 5628 5629 5630 5631 5632 5633

	.file_permission =		selinux_file_permission,
	.file_alloc_security =		selinux_file_alloc_security,
	.file_free_security =		selinux_file_free_security,
	.file_ioctl =			selinux_file_ioctl,
	.file_mmap =			selinux_file_mmap,
	.file_mprotect =		selinux_file_mprotect,
	.file_lock =			selinux_file_lock,
	.file_fcntl =			selinux_file_fcntl,
	.file_set_fowner =		selinux_file_set_fowner,
	.file_send_sigiotask =		selinux_file_send_sigiotask,
	.file_receive =			selinux_file_receive,

5634
	.dentry_open =			selinux_dentry_open,
5635

L
Linus Torvalds 已提交
5636
	.task_create =			selinux_task_create,
5637
	.cred_free =			selinux_cred_free,
D
David Howells 已提交
5638 5639
	.cred_prepare =			selinux_cred_prepare,
	.cred_commit =			selinux_cred_commit,
5640 5641
	.kernel_act_as =		selinux_kernel_act_as,
	.kernel_create_files_as =	selinux_kernel_create_files_as,
L
Linus Torvalds 已提交
5642
	.task_setuid =			selinux_task_setuid,
D
David Howells 已提交
5643
	.task_fix_setuid =		selinux_task_fix_setuid,
L
Linus Torvalds 已提交
5644 5645 5646
	.task_setgid =			selinux_task_setgid,
	.task_setpgid =			selinux_task_setpgid,
	.task_getpgid =			selinux_task_getpgid,
5647
	.task_getsid =			selinux_task_getsid,
5648
	.task_getsecid =		selinux_task_getsecid,
L
Linus Torvalds 已提交
5649 5650
	.task_setgroups =		selinux_task_setgroups,
	.task_setnice =			selinux_task_setnice,
5651
	.task_setioprio =		selinux_task_setioprio,
5652
	.task_getioprio =		selinux_task_getioprio,
L
Linus Torvalds 已提交
5653 5654 5655
	.task_setrlimit =		selinux_task_setrlimit,
	.task_setscheduler =		selinux_task_setscheduler,
	.task_getscheduler =		selinux_task_getscheduler,
5656
	.task_movememory =		selinux_task_movememory,
L
Linus Torvalds 已提交
5657 5658 5659
	.task_kill =			selinux_task_kill,
	.task_wait =			selinux_task_wait,
	.task_prctl =			selinux_task_prctl,
5660
	.task_to_inode =		selinux_task_to_inode,
L
Linus Torvalds 已提交
5661 5662

	.ipc_permission =		selinux_ipc_permission,
5663
	.ipc_getsecid =			selinux_ipc_getsecid,
L
Linus Torvalds 已提交
5664 5665 5666 5667 5668 5669 5670 5671 5672 5673 5674 5675 5676 5677 5678 5679 5680

	.msg_msg_alloc_security =	selinux_msg_msg_alloc_security,
	.msg_msg_free_security =	selinux_msg_msg_free_security,

	.msg_queue_alloc_security =	selinux_msg_queue_alloc_security,
	.msg_queue_free_security =	selinux_msg_queue_free_security,
	.msg_queue_associate =		selinux_msg_queue_associate,
	.msg_queue_msgctl =		selinux_msg_queue_msgctl,
	.msg_queue_msgsnd =		selinux_msg_queue_msgsnd,
	.msg_queue_msgrcv =		selinux_msg_queue_msgrcv,

	.shm_alloc_security =		selinux_shm_alloc_security,
	.shm_free_security =		selinux_shm_free_security,
	.shm_associate =		selinux_shm_associate,
	.shm_shmctl =			selinux_shm_shmctl,
	.shm_shmat =			selinux_shm_shmat,

5681 5682
	.sem_alloc_security =		selinux_sem_alloc_security,
	.sem_free_security =		selinux_sem_free_security,
L
Linus Torvalds 已提交
5683 5684 5685 5686
	.sem_associate =		selinux_sem_associate,
	.sem_semctl =			selinux_sem_semctl,
	.sem_semop =			selinux_sem_semop,

5687
	.d_instantiate =		selinux_d_instantiate,
L
Linus Torvalds 已提交
5688

5689 5690
	.getprocattr =			selinux_getprocattr,
	.setprocattr =			selinux_setprocattr,
L
Linus Torvalds 已提交
5691

5692
	.secid_to_secctx =		selinux_secid_to_secctx,
5693
	.secctx_to_secid =		selinux_secctx_to_secid,
5694 5695
	.release_secctx =		selinux_release_secctx,

5696
	.unix_stream_connect =		selinux_socket_unix_stream_connect,
L
Linus Torvalds 已提交
5697 5698 5699 5700 5701 5702 5703 5704 5705 5706 5707 5708 5709 5710 5711 5712
	.unix_may_send =		selinux_socket_unix_may_send,

	.socket_create =		selinux_socket_create,
	.socket_post_create =		selinux_socket_post_create,
	.socket_bind =			selinux_socket_bind,
	.socket_connect =		selinux_socket_connect,
	.socket_listen =		selinux_socket_listen,
	.socket_accept =		selinux_socket_accept,
	.socket_sendmsg =		selinux_socket_sendmsg,
	.socket_recvmsg =		selinux_socket_recvmsg,
	.socket_getsockname =		selinux_socket_getsockname,
	.socket_getpeername =		selinux_socket_getpeername,
	.socket_getsockopt =		selinux_socket_getsockopt,
	.socket_setsockopt =		selinux_socket_setsockopt,
	.socket_shutdown =		selinux_socket_shutdown,
	.socket_sock_rcv_skb =		selinux_socket_sock_rcv_skb,
C
Catherine Zhang 已提交
5713 5714
	.socket_getpeersec_stream =	selinux_socket_getpeersec_stream,
	.socket_getpeersec_dgram =	selinux_socket_getpeersec_dgram,
L
Linus Torvalds 已提交
5715 5716
	.sk_alloc_security =		selinux_sk_alloc_security,
	.sk_free_security =		selinux_sk_free_security,
5717
	.sk_clone_security =		selinux_sk_clone_security,
5718
	.sk_getsecid =			selinux_sk_getsecid,
5719 5720 5721
	.sock_graft =			selinux_sock_graft,
	.inet_conn_request =		selinux_inet_conn_request,
	.inet_csk_clone =		selinux_inet_csk_clone,
5722
	.inet_conn_established =	selinux_inet_conn_established,
5723
	.req_classify_flow =		selinux_req_classify_flow,
5724 5725 5726 5727 5728

#ifdef CONFIG_SECURITY_NETWORK_XFRM
	.xfrm_policy_alloc_security =	selinux_xfrm_policy_alloc,
	.xfrm_policy_clone_security =	selinux_xfrm_policy_clone,
	.xfrm_policy_free_security =	selinux_xfrm_policy_free,
C
Catherine Zhang 已提交
5729
	.xfrm_policy_delete_security =	selinux_xfrm_policy_delete,
5730 5731
	.xfrm_state_alloc_security =	selinux_xfrm_state_alloc,
	.xfrm_state_free_security =	selinux_xfrm_state_free,
C
Catherine Zhang 已提交
5732
	.xfrm_state_delete_security =	selinux_xfrm_state_delete,
5733
	.xfrm_policy_lookup =		selinux_xfrm_policy_lookup,
5734 5735
	.xfrm_state_pol_flow_match =	selinux_xfrm_state_pol_flow_match,
	.xfrm_decode_session =		selinux_xfrm_decode_session,
L
Linus Torvalds 已提交
5736
#endif
5737 5738

#ifdef CONFIG_KEYS
5739 5740 5741
	.key_alloc =			selinux_key_alloc,
	.key_free =			selinux_key_free,
	.key_permission =		selinux_key_permission,
5742
	.key_getsecurity =		selinux_key_getsecurity,
5743
#endif
5744 5745 5746 5747 5748 5749 5750

#ifdef CONFIG_AUDIT
	.audit_rule_init =		selinux_audit_rule_init,
	.audit_rule_known =		selinux_audit_rule_known,
	.audit_rule_match =		selinux_audit_rule_match,
	.audit_rule_free =		selinux_audit_rule_free,
#endif
L
Linus Torvalds 已提交
5751 5752 5753 5754
};

static __init int selinux_init(void)
{
5755 5756 5757 5758 5759
	if (!security_module_enable(&selinux_ops)) {
		selinux_enabled = 0;
		return 0;
	}

L
Linus Torvalds 已提交
5760 5761 5762 5763 5764 5765 5766 5767
	if (!selinux_enabled) {
		printk(KERN_INFO "SELinux:  Disabled at boot.\n");
		return 0;
	}

	printk(KERN_INFO "SELinux:  Initializing.\n");

	/* Set the security state for the initial task. */
D
David Howells 已提交
5768
	cred_init_security();
L
Linus Torvalds 已提交
5769

5770 5771
	sel_inode_cache = kmem_cache_create("selinux_inode_security",
					    sizeof(struct inode_security_struct),
5772
					    0, SLAB_PANIC, NULL);
L
Linus Torvalds 已提交
5773 5774
	avc_init();

5775
	secondary_ops = security_ops;
L
Linus Torvalds 已提交
5776
	if (!secondary_ops)
5777 5778
		panic("SELinux: No initial security operations\n");
	if (register_security(&selinux_ops))
L
Linus Torvalds 已提交
5779 5780
		panic("SELinux: Unable to register with kernel.\n");

5781
	if (selinux_enforcing)
5782
		printk(KERN_DEBUG "SELinux:  Starting in enforcing mode\n");
5783
	else
5784
		printk(KERN_DEBUG "SELinux:  Starting in permissive mode\n");
5785

L
Linus Torvalds 已提交
5786 5787 5788 5789 5790
	return 0;
}

void selinux_complete_init(void)
{
5791
	printk(KERN_DEBUG "SELinux:  Completing initialization.\n");
L
Linus Torvalds 已提交
5792 5793

	/* Set up any superblocks initialized prior to the policy load. */
5794
	printk(KERN_DEBUG "SELinux:  Setting up existing superblocks.\n");
5795
	spin_lock(&sb_lock);
L
Linus Torvalds 已提交
5796 5797 5798 5799 5800
	spin_lock(&sb_security_lock);
next_sb:
	if (!list_empty(&superblock_security_head)) {
		struct superblock_security_struct *sbsec =
				list_entry(superblock_security_head.next,
5801 5802
					   struct superblock_security_struct,
					   list);
L
Linus Torvalds 已提交
5803 5804 5805
		struct super_block *sb = sbsec->sb;
		sb->s_count++;
		spin_unlock(&sb_security_lock);
5806
		spin_unlock(&sb_lock);
L
Linus Torvalds 已提交
5807 5808 5809 5810
		down_read(&sb->s_umount);
		if (sb->s_root)
			superblock_doinit(sb, NULL);
		drop_super(sb);
5811
		spin_lock(&sb_lock);
L
Linus Torvalds 已提交
5812 5813 5814 5815 5816
		spin_lock(&sb_security_lock);
		list_del_init(&sbsec->list);
		goto next_sb;
	}
	spin_unlock(&sb_security_lock);
5817
	spin_unlock(&sb_lock);
L
Linus Torvalds 已提交
5818 5819 5820 5821 5822 5823
}

/* SELinux requires early initialization in order to label
   all processes and objects when they are created. */
security_initcall(selinux_init);

5824
#if defined(CONFIG_NETFILTER)
L
Linus Torvalds 已提交
5825

5826 5827 5828 5829 5830 5831 5832 5833 5834 5835 5836 5837 5838 5839
static struct nf_hook_ops selinux_ipv4_ops[] = {
	{
		.hook =		selinux_ipv4_postroute,
		.owner =	THIS_MODULE,
		.pf =		PF_INET,
		.hooknum =	NF_INET_POST_ROUTING,
		.priority =	NF_IP_PRI_SELINUX_LAST,
	},
	{
		.hook =		selinux_ipv4_forward,
		.owner =	THIS_MODULE,
		.pf =		PF_INET,
		.hooknum =	NF_INET_FORWARD,
		.priority =	NF_IP_PRI_SELINUX_FIRST,
5840 5841 5842 5843 5844 5845 5846
	},
	{
		.hook =		selinux_ipv4_output,
		.owner =	THIS_MODULE,
		.pf =		PF_INET,
		.hooknum =	NF_INET_LOCAL_OUT,
		.priority =	NF_IP_PRI_SELINUX_FIRST,
5847
	}
L
Linus Torvalds 已提交
5848 5849 5850 5851
};

#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)

5852 5853 5854 5855 5856 5857 5858 5859 5860 5861 5862 5863 5864 5865 5866
static struct nf_hook_ops selinux_ipv6_ops[] = {
	{
		.hook =		selinux_ipv6_postroute,
		.owner =	THIS_MODULE,
		.pf =		PF_INET6,
		.hooknum =	NF_INET_POST_ROUTING,
		.priority =	NF_IP6_PRI_SELINUX_LAST,
	},
	{
		.hook =		selinux_ipv6_forward,
		.owner =	THIS_MODULE,
		.pf =		PF_INET6,
		.hooknum =	NF_INET_FORWARD,
		.priority =	NF_IP6_PRI_SELINUX_FIRST,
	}
L
Linus Torvalds 已提交
5867 5868 5869 5870 5871 5872 5873 5874 5875 5876
};

#endif	/* IPV6 */

static int __init selinux_nf_ip_init(void)
{
	int err = 0;

	if (!selinux_enabled)
		goto out;
5877 5878 5879

	printk(KERN_DEBUG "SELinux:  Registering netfilter hooks\n");

5880 5881 5882
	err = nf_register_hooks(selinux_ipv4_ops, ARRAY_SIZE(selinux_ipv4_ops));
	if (err)
		panic("SELinux: nf_register_hooks for IPv4: error %d\n", err);
L
Linus Torvalds 已提交
5883 5884

#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
5885 5886 5887
	err = nf_register_hooks(selinux_ipv6_ops, ARRAY_SIZE(selinux_ipv6_ops));
	if (err)
		panic("SELinux: nf_register_hooks for IPv6: error %d\n", err);
L
Linus Torvalds 已提交
5888
#endif	/* IPV6 */
5889

L
Linus Torvalds 已提交
5890 5891 5892 5893 5894 5895 5896 5897 5898
out:
	return err;
}

__initcall(selinux_nf_ip_init);

#ifdef CONFIG_SECURITY_SELINUX_DISABLE
static void selinux_nf_ip_exit(void)
{
5899
	printk(KERN_DEBUG "SELinux:  Unregistering netfilter hooks\n");
L
Linus Torvalds 已提交
5900

5901
	nf_unregister_hooks(selinux_ipv4_ops, ARRAY_SIZE(selinux_ipv4_ops));
L
Linus Torvalds 已提交
5902
#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
5903
	nf_unregister_hooks(selinux_ipv6_ops, ARRAY_SIZE(selinux_ipv6_ops));
L
Linus Torvalds 已提交
5904 5905 5906 5907
#endif	/* IPV6 */
}
#endif

5908
#else /* CONFIG_NETFILTER */
L
Linus Torvalds 已提交
5909 5910 5911 5912 5913

#ifdef CONFIG_SECURITY_SELINUX_DISABLE
#define selinux_nf_ip_exit()
#endif

5914
#endif /* CONFIG_NETFILTER */
L
Linus Torvalds 已提交
5915 5916

#ifdef CONFIG_SECURITY_SELINUX_DISABLE
5917 5918
static int selinux_disabled;

L
Linus Torvalds 已提交
5919 5920 5921 5922 5923 5924 5925 5926 5927 5928 5929 5930 5931 5932 5933 5934 5935
int selinux_disable(void)
{
	extern void exit_sel_fs(void);

	if (ss_initialized) {
		/* Not permitted after initial policy load. */
		return -EINVAL;
	}

	if (selinux_disabled) {
		/* Only do this once. */
		return -EINVAL;
	}

	printk(KERN_INFO "SELinux:  Disabled at runtime.\n");

	selinux_disabled = 1;
5936
	selinux_enabled = 0;
L
Linus Torvalds 已提交
5937 5938 5939 5940 5941 5942 5943 5944 5945 5946 5947 5948 5949

	/* Reset security_ops to the secondary module, dummy or capability. */
	security_ops = secondary_ops;

	/* Unregister netfilter hooks. */
	selinux_nf_ip_exit();

	/* Unregister selinuxfs. */
	exit_sel_fs();

	return 0;
}
#endif