hooks.c 150.0 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, 2009 Hewlett-Packard Development Company, L.P.
17
 *	Paul Moore <paul@paul-moore.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
 */

#include <linux/init.h>
27
#include <linux/kd.h>
L
Linus Torvalds 已提交
28
#include <linux/kernel.h>
29
#include <linux/tracehook.h>
L
Linus Torvalds 已提交
30 31 32 33 34 35 36 37 38 39
#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>
40
#include <linux/proc_fs.h>
L
Linus Torvalds 已提交
41 42 43
#include <linux/swap.h>
#include <linux/spinlock.h>
#include <linux/syscalls.h>
44
#include <linux/dcache.h>
L
Linus Torvalds 已提交
45
#include <linux/file.h>
A
Al Viro 已提交
46
#include <linux/fdtable.h>
L
Linus Torvalds 已提交
47 48 49 50 51 52
#include <linux/namei.h>
#include <linux/mount.h>
#include <linux/netfilter_ipv4.h>
#include <linux/netfilter_ipv6.h>
#include <linux/tty.h>
#include <net/icmp.h>
53
#include <net/ip.h>		/* for local_port_range[] */
54
#include <net/sock.h>
L
Linus Torvalds 已提交
55
#include <net/tcp.h>		/* struct or_callable used in sock_rcv_skb */
56
#include <net/inet_connection_sock.h>
57
#include <net/net_namespace.h>
58
#include <net/netlabel.h>
59
#include <linux/uaccess.h>
L
Linus Torvalds 已提交
60
#include <asm/ioctls.h>
A
Arun Sharma 已提交
61
#include <linux/atomic.h>
L
Linus Torvalds 已提交
62 63 64
#include <linux/bitops.h>
#include <linux/interrupt.h>
#include <linux/netdevice.h>	/* for network interface checks */
65
#include <net/netlink.h>
L
Linus Torvalds 已提交
66 67
#include <linux/tcp.h>
#include <linux/udp.h>
J
James Morris 已提交
68
#include <linux/dccp.h>
L
Linus Torvalds 已提交
69 70 71 72 73 74 75 76 77
#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/audit.h>
78
#include <linux/string.h>
C
Catherine Zhang 已提交
79
#include <linux/selinux.h>
80
#include <linux/mutex.h>
81
#include <linux/posix-timers.h>
82
#include <linux/syslog.h>
83
#include <linux/user_namespace.h>
84
#include <linux/export.h>
A
Al Viro 已提交
85 86
#include <linux/msg.h>
#include <linux/shm.h>
L
Linus Torvalds 已提交
87 88 89 90

#include "avc.h"
#include "objsec.h"
#include "netif.h"
91
#include "netnode.h"
P
Paul Moore 已提交
92
#include "netport.h"
93
#include "xfrm.h"
94
#include "netlabel.h"
95
#include "audit.h"
96
#include "avc_ss.h"
L
Linus Torvalds 已提交
97

98
extern struct security_operations *security_ops;
L
Linus Torvalds 已提交
99

100
/* SECMARK reference count */
101
static atomic_t selinux_secmark_refcount = ATOMIC_INIT(0);
102

L
Linus Torvalds 已提交
103
#ifdef CONFIG_SECURITY_SELINUX_DEVELOP
104
int selinux_enforcing;
L
Linus Torvalds 已提交
105 106 107

static int __init enforcing_setup(char *str)
{
108
	unsigned long enforcing;
109
	if (!kstrtoul(str, 0, &enforcing))
110
		selinux_enforcing = enforcing ? 1 : 0;
L
Linus Torvalds 已提交
111 112 113 114 115 116 117 118 119 120
	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)
{
121
	unsigned long enabled;
122
	if (!kstrtoul(str, 0, &enabled))
123
		selinux_enabled = enabled ? 1 : 0;
L
Linus Torvalds 已提交
124 125 126
	return 1;
}
__setup("selinux=", selinux_enabled_setup);
127 128
#else
int selinux_enabled = 1;
L
Linus Torvalds 已提交
129 130
#endif

131
static struct kmem_cache *sel_inode_cache;
132

133 134 135 136 137 138 139
/**
 * 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
140 141
 * enabled, false (0) if SECMARK is disabled.  If the always_check_network
 * policy capability is enabled, SECMARK is always considered enabled.
142 143 144 145
 *
 */
static int selinux_secmark_enabled(void)
{
146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161
	return (selinux_policycap_alwaysnetwork || atomic_read(&selinux_secmark_refcount));
}

/**
 * selinux_peerlbl_enabled - Check to see if peer labeling is currently enabled
 *
 * Description:
 * This function checks if NetLabel or labeled IPSEC is enabled.  Returns true
 * (1) if any are enabled or false (0) if neither are enabled.  If the
 * always_check_network policy capability is enabled, peer labeling
 * is always considered enabled.
 *
 */
static int selinux_peerlbl_enabled(void)
{
	return (selinux_policycap_alwaysnetwork || netlbl_enabled() || selinux_xfrm_enabled());
162 163
}

D
David Howells 已提交
164 165 166 167
/*
 * initialise the security for the init task
 */
static void cred_init_security(void)
L
Linus Torvalds 已提交
168
{
169
	struct cred *cred = (struct cred *) current->real_cred;
L
Linus Torvalds 已提交
170 171
	struct task_security_struct *tsec;

J
James Morris 已提交
172
	tsec = kzalloc(sizeof(struct task_security_struct), GFP_KERNEL);
L
Linus Torvalds 已提交
173
	if (!tsec)
D
David Howells 已提交
174
		panic("SELinux:  Failed to initialize initial task.\n");
L
Linus Torvalds 已提交
175

D
David Howells 已提交
176
	tsec->osid = tsec->sid = SECINITSID_KERNEL;
177
	cred->security = tsec;
L
Linus Torvalds 已提交
178 179
}

180 181 182 183 184 185 186 187 188 189 190
/*
 * 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;
}

191
/*
192
 * get the objective security ID of a task
193 194 195 196 197 198
 */
static inline u32 task_sid(const struct task_struct *task)
{
	u32 sid;

	rcu_read_lock();
199
	sid = cred_sid(__task_cred(task));
200 201 202 203 204
	rcu_read_unlock();
	return sid;
}

/*
205
 * get the subjective security ID of the current task
206 207 208
 */
static inline u32 current_sid(void)
{
209
	const struct task_security_struct *tsec = current_security();
210 211 212 213

	return tsec->sid;
}

214 215
/* Allocate and free functions for each kind of security blob. */

L
Linus Torvalds 已提交
216 217 218
static int inode_alloc_security(struct inode *inode)
{
	struct inode_security_struct *isec;
219
	u32 sid = current_sid();
L
Linus Torvalds 已提交
220

221
	isec = kmem_cache_zalloc(sel_inode_cache, GFP_NOFS);
L
Linus Torvalds 已提交
222 223 224
	if (!isec)
		return -ENOMEM;

225
	mutex_init(&isec->lock);
L
Linus Torvalds 已提交
226 227 228 229
	INIT_LIST_HEAD(&isec->list);
	isec->inode = inode;
	isec->sid = SECINITSID_UNLABELED;
	isec->sclass = SECCLASS_FILE;
230
	isec->task_sid = sid;
L
Linus Torvalds 已提交
231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246
	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;
247
	kmem_cache_free(sel_inode_cache, isec);
L
Linus Torvalds 已提交
248 249 250 251 252
}

static int file_alloc_security(struct file *file)
{
	struct file_security_struct *fsec;
253
	u32 sid = current_sid();
L
Linus Torvalds 已提交
254

255
	fsec = kzalloc(sizeof(struct file_security_struct), GFP_KERNEL);
L
Linus Torvalds 已提交
256 257 258
	if (!fsec)
		return -ENOMEM;

259 260
	fsec->sid = sid;
	fsec->fown_sid = sid;
L
Linus Torvalds 已提交
261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276
	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
277
	sbsec = kzalloc(sizeof(struct superblock_security_struct), GFP_KERNEL);
L
Linus Torvalds 已提交
278 279 280
	if (!sbsec)
		return -ENOMEM;

281
	mutex_init(&sbsec->lock);
L
Linus Torvalds 已提交
282 283 284 285 286
	INIT_LIST_HEAD(&sbsec->isec_head);
	spin_lock_init(&sbsec->isec_lock);
	sbsec->sb = sb;
	sbsec->sid = SECINITSID_UNLABELED;
	sbsec->def_sid = SECINITSID_FILE;
287
	sbsec->mntpoint_sid = SECINITSID_UNLABELED;
L
Linus Torvalds 已提交
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;
	sb->s_security = NULL;
	kfree(sbsec);
}

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

302
static const char *labeling_behaviors[7] = {
L
Linus Torvalds 已提交
303 304 305 306 307 308
	"uses xattr",
	"uses transition SIDs",
	"uses task SIDs",
	"uses genfs_contexts",
	"not configured for labeling",
	"uses mountpoint labeling",
309
	"uses native labeling",
L
Linus Torvalds 已提交
310 311 312 313 314 315 316 317 318 319
};

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 {
320
	Opt_error = -1,
L
Linus Torvalds 已提交
321 322
	Opt_context = 1,
	Opt_fscontext = 2,
323 324
	Opt_defcontext = 3,
	Opt_rootcontext = 4,
325
	Opt_labelsupport = 5,
326
	Opt_nextmntopt = 6,
L
Linus Torvalds 已提交
327 328
};

329 330
#define NUM_SEL_MNT_OPTS	(Opt_nextmntopt - 1)

331
static const match_table_t tokens = {
332 333 334 335
	{Opt_context, CONTEXT_STR "%s"},
	{Opt_fscontext, FSCONTEXT_STR "%s"},
	{Opt_defcontext, DEFCONTEXT_STR "%s"},
	{Opt_rootcontext, ROOTCONTEXT_STR "%s"},
336
	{Opt_labelsupport, LABELSUPP_STR},
337
	{Opt_error, NULL},
L
Linus Torvalds 已提交
338 339 340 341
};

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

342 343
static int may_context_mount_sb_relabel(u32 sid,
			struct superblock_security_struct *sbsec,
344
			const struct cred *cred)
345
{
346
	const struct task_security_struct *tsec = cred->security;
347 348 349 350 351 352 353 354 355 356 357 358
	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;
}

359 360
static int may_context_mount_inode_relabel(u32 sid,
			struct superblock_security_struct *sbsec,
361
			const struct cred *cred)
362
{
363
	const struct task_security_struct *tsec = cred->security;
364 365 366 367 368 369 370 371 372 373 374
	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;
}

375 376 377 378 379 380 381 382 383 384 385 386 387 388 389 390 391 392 393 394 395 396 397
static int selinux_is_sblabel_mnt(struct super_block *sb)
{
	struct superblock_security_struct *sbsec = sb->s_security;

	if (sbsec->behavior == SECURITY_FS_USE_XATTR ||
	    sbsec->behavior == SECURITY_FS_USE_TRANS ||
	    sbsec->behavior == SECURITY_FS_USE_TASK)
		return 1;

	/* Special handling for sysfs. Is genfs but also has setxattr handler*/
	if (strncmp(sb->s_type->name, "sysfs", sizeof("sysfs")) == 0)
		return 1;

	/*
	 * Special handling for rootfs. Is genfs but supports
	 * setting SELinux context on in-core inodes.
	 */
	if (strncmp(sb->s_type->name, "rootfs", sizeof("rootfs")) == 0)
		return 1;

	return 0;
}

398
static int sb_finish_set_opts(struct super_block *sb)
L
Linus Torvalds 已提交
399 400
{
	struct superblock_security_struct *sbsec = sb->s_security;
401 402 403
	struct dentry *root = sb->s_root;
	struct inode *root_inode = root->d_inode;
	int rc = 0;
L
Linus Torvalds 已提交
404

405 406 407 408 409 410 411
	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) {
412 413
			printk(KERN_WARNING "SELinux: (dev %s, type %s) has no "
			       "xattr support\n", sb->s_id, sb->s_type->name);
414 415 416 417 418 419 420
			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 "
421 422
				       "%s) has no security xattr handler\n",
				       sb->s_id, sb->s_type->name);
423 424
			else
				printk(KERN_WARNING "SELinux: (dev %s, type "
425 426
				       "%s) getxattr errno %d\n", sb->s_id,
				       sb->s_type->name, -rc);
427 428 429
			goto out;
		}
	}
L
Linus Torvalds 已提交
430

431
	if (sbsec->behavior > ARRAY_SIZE(labeling_behaviors))
432 433
		printk(KERN_ERR "SELinux: initialized (dev %s, type %s), unknown behavior\n",
		       sb->s_id, sb->s_type->name);
434
	else
435 436
		printk(KERN_DEBUG "SELinux: initialized (dev %s, type %s), %s\n",
		       sb->s_id, sb->s_type->name,
437
		       labeling_behaviors[sbsec->behavior-1]);
L
Linus Torvalds 已提交
438

439
	sbsec->flags |= SE_SBINITIALIZED;
440
	if (selinux_is_sblabel_mnt(sb))
441
		sbsec->flags |= SBLABEL_MNT;
442

443 444
	/* Initialize the root inode. */
	rc = inode_doinit_with_dentry(root_inode, root);
L
Linus Torvalds 已提交
445

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
	/* 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
472

473 474 475 476 477 478
/*
 * 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,
479
				struct security_mnt_opts *opts)
480 481 482 483 484 485
{
	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
486

487
	security_init_mnt_opts(opts);
L
Linus Torvalds 已提交
488

489
	if (!(sbsec->flags & SE_SBINITIALIZED))
490
		return -EINVAL;
L
Linus Torvalds 已提交
491

492 493
	if (!ss_initialized)
		return -EINVAL;
L
Linus Torvalds 已提交
494

495 496 497
	/* make sure we always check enough bits to cover the mask */
	BUILD_BUG_ON(SE_MNTMASK >= (1 << NUM_SEL_MNT_OPTS));

498
	tmp = sbsec->flags & SE_MNTMASK;
499
	/* count the number of mount options for this sb */
500
	for (i = 0; i < NUM_SEL_MNT_OPTS; i++) {
501
		if (tmp & 0x01)
502
			opts->num_mnt_opts++;
503 504
		tmp >>= 1;
	}
505
	/* Check if the Label support flag is set */
506
	if (sbsec->flags & SBLABEL_MNT)
507
		opts->num_mnt_opts++;
L
Linus Torvalds 已提交
508

509 510
	opts->mnt_opts = kcalloc(opts->num_mnt_opts, sizeof(char *), GFP_ATOMIC);
	if (!opts->mnt_opts) {
511 512 513
		rc = -ENOMEM;
		goto out_free;
	}
L
Linus Torvalds 已提交
514

515 516
	opts->mnt_opts_flags = kcalloc(opts->num_mnt_opts, sizeof(int), GFP_ATOMIC);
	if (!opts->mnt_opts_flags) {
517 518 519
		rc = -ENOMEM;
		goto out_free;
	}
L
Linus Torvalds 已提交
520

521 522 523 524 525
	i = 0;
	if (sbsec->flags & FSCONTEXT_MNT) {
		rc = security_sid_to_context(sbsec->sid, &context, &len);
		if (rc)
			goto out_free;
526 527
		opts->mnt_opts[i] = context;
		opts->mnt_opts_flags[i++] = FSCONTEXT_MNT;
528 529 530 531 532
	}
	if (sbsec->flags & CONTEXT_MNT) {
		rc = security_sid_to_context(sbsec->mntpoint_sid, &context, &len);
		if (rc)
			goto out_free;
533 534
		opts->mnt_opts[i] = context;
		opts->mnt_opts_flags[i++] = CONTEXT_MNT;
535 536 537 538 539
	}
	if (sbsec->flags & DEFCONTEXT_MNT) {
		rc = security_sid_to_context(sbsec->def_sid, &context, &len);
		if (rc)
			goto out_free;
540 541
		opts->mnt_opts[i] = context;
		opts->mnt_opts_flags[i++] = DEFCONTEXT_MNT;
542 543 544 545
	}
	if (sbsec->flags & ROOTCONTEXT_MNT) {
		struct inode *root = sbsec->sb->s_root->d_inode;
		struct inode_security_struct *isec = root->i_security;
546

547 548 549
		rc = security_sid_to_context(isec->sid, &context, &len);
		if (rc)
			goto out_free;
550 551
		opts->mnt_opts[i] = context;
		opts->mnt_opts_flags[i++] = ROOTCONTEXT_MNT;
552
	}
553
	if (sbsec->flags & SBLABEL_MNT) {
554
		opts->mnt_opts[i] = NULL;
555
		opts->mnt_opts_flags[i++] = SBLABEL_MNT;
556
	}
L
Linus Torvalds 已提交
557

558
	BUG_ON(i != opts->num_mnt_opts);
L
Linus Torvalds 已提交
559

560 561 562
	return 0;

out_free:
563
	security_free_mnt_opts(opts);
564 565
	return rc;
}
L
Linus Torvalds 已提交
566

567 568 569
static int bad_option(struct superblock_security_struct *sbsec, char flag,
		      u32 old_sid, u32 new_sid)
{
570 571
	char mnt_flags = sbsec->flags & SE_MNTMASK;

572
	/* check if the old mount command had the same options */
573
	if (sbsec->flags & SE_SBINITIALIZED)
574 575 576 577 578 579 580
		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
	 */
581 582
	if (!(sbsec->flags & SE_SBINITIALIZED))
		if (mnt_flags & flag)
583 584 585
			return 1;
	return 0;
}
586

587 588 589 590
/*
 * Allow filesystems with binary mount data to explicitly set mount point
 * labeling information.
 */
591
static int selinux_set_mnt_opts(struct super_block *sb,
592 593 594
				struct security_mnt_opts *opts,
				unsigned long kern_flags,
				unsigned long *set_kern_flags)
595
{
596
	const struct cred *cred = current_cred();
597 598
	int rc = 0, i;
	struct superblock_security_struct *sbsec = sb->s_security;
599
	const char *name = sb->s_type->name;
600 601
	struct inode *inode = sbsec->sb->s_root->d_inode;
	struct inode_security_struct *root_isec = inode->i_security;
602 603
	u32 fscontext_sid = 0, context_sid = 0, rootcontext_sid = 0;
	u32 defcontext_sid = 0;
604 605 606
	char **mount_options = opts->mnt_opts;
	int *flags = opts->mnt_opts_flags;
	int num_opts = opts->num_mnt_opts;
607 608 609 610 611 612 613 614 615 616 617

	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. */
			goto out;
		}
		rc = -EINVAL;
E
Eric Paris 已提交
618 619
		printk(KERN_WARNING "SELinux: Unable to set superblock options "
			"before the security server is initialized\n");
L
Linus Torvalds 已提交
620
		goto out;
621
	}
622 623 624 625 626 627
	if (kern_flags && !set_kern_flags) {
		/* Specifying internal flags without providing a place to
		 * place the results is not allowed */
		rc = -EINVAL;
		goto out;
	}
L
Linus Torvalds 已提交
628

629 630 631 632 633 634 635 636 637 638 639
	/*
	 * 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)
	 */
640
	if ((sbsec->flags & SE_SBINITIALIZED) && (sb->s_type->fs_flags & FS_BINARY_MOUNTDATA)
641
	    && (num_opts == 0))
642
		goto out;
643

644 645 646 647 648 649 650
	/*
	 * 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;
651

652
		if (flags[i] == SBLABEL_MNT)
653
			continue;
654 655
		rc = security_context_to_sid(mount_options[i],
					     strlen(mount_options[i]), &sid);
L
Linus Torvalds 已提交
656 657
		if (rc) {
			printk(KERN_WARNING "SELinux: security_context_to_sid"
658 659
			       "(%s) failed for (dev %s, type %s) errno=%d\n",
			       mount_options[i], sb->s_id, name, rc);
660 661 662 663 664 665 666 667 668 669 670 671 672 673 674 675 676 677 678 679 680 681 682 683 684 685 686 687 688 689 690 691 692 693 694 695 696 697 698 699 700 701 702 703
			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
704
		}
705 706
	}

707
	if (sbsec->flags & SE_SBINITIALIZED) {
708
		/* previously mounted with options, but not on this attempt? */
709
		if ((sbsec->flags & SE_MNTMASK) && !num_opts)
710 711 712 713 714
			goto out_double_mount;
		rc = 0;
		goto out;
	}

715
	if (strcmp(sb->s_type->name, "proc") == 0)
716
		sbsec->flags |= SE_SBPROC;
717

718 719 720 721 722
	if (!sbsec->behavior) {
		/*
		 * Determine the labeling behavior to use for this
		 * filesystem type.
		 */
723
		rc = security_fs_use(sb);
724 725 726 727 728 729
		if (rc) {
			printk(KERN_WARNING
				"%s: security_fs_use(%s) returned %d\n",
					__func__, sb->s_type->name, rc);
			goto out;
		}
730 731 732
	}
	/* sets the context of the superblock for the fs being mounted. */
	if (fscontext_sid) {
733
		rc = may_context_mount_sb_relabel(fscontext_sid, sbsec, cred);
L
Linus Torvalds 已提交
734
		if (rc)
735
			goto out;
L
Linus Torvalds 已提交
736

737
		sbsec->sid = fscontext_sid;
738 739 740 741 742 743 744
	}

	/*
	 * 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.
	 */
745 746 747 748 749
	if (kern_flags & SECURITY_LSM_NATIVE_LABELS && !context_sid) {
		sbsec->behavior = SECURITY_FS_USE_NATIVE;
		*set_kern_flags |= SECURITY_LSM_NATIVE_LABELS;
	}

750 751
	if (context_sid) {
		if (!fscontext_sid) {
752 753
			rc = may_context_mount_sb_relabel(context_sid, sbsec,
							  cred);
754
			if (rc)
755 756
				goto out;
			sbsec->sid = context_sid;
757
		} else {
758 759
			rc = may_context_mount_inode_relabel(context_sid, sbsec,
							     cred);
760
			if (rc)
761
				goto out;
762
		}
763 764
		if (!rootcontext_sid)
			rootcontext_sid = context_sid;
L
Linus Torvalds 已提交
765

766
		sbsec->mntpoint_sid = context_sid;
767
		sbsec->behavior = SECURITY_FS_USE_MNTPOINT;
L
Linus Torvalds 已提交
768 769
	}

770
	if (rootcontext_sid) {
771 772
		rc = may_context_mount_inode_relabel(rootcontext_sid, sbsec,
						     cred);
773
		if (rc)
774
			goto out;
775

776 777
		root_isec->sid = rootcontext_sid;
		root_isec->initialized = 1;
778 779
	}

780
	if (defcontext_sid) {
781 782
		if (sbsec->behavior != SECURITY_FS_USE_XATTR &&
			sbsec->behavior != SECURITY_FS_USE_NATIVE) {
783 784 785 786
			rc = -EINVAL;
			printk(KERN_WARNING "SELinux: defcontext option is "
			       "invalid for this filesystem type\n");
			goto out;
L
Linus Torvalds 已提交
787 788
		}

789 790
		if (defcontext_sid != sbsec->def_sid) {
			rc = may_context_mount_inode_relabel(defcontext_sid,
791
							     sbsec, cred);
792 793 794
			if (rc)
				goto out;
		}
L
Linus Torvalds 已提交
795

796
		sbsec->def_sid = defcontext_sid;
L
Linus Torvalds 已提交
797 798
	}

799
	rc = sb_finish_set_opts(sb);
L
Linus Torvalds 已提交
800
out:
801
	mutex_unlock(&sbsec->lock);
L
Linus Torvalds 已提交
802
	return rc;
803 804 805
out_double_mount:
	rc = -EINVAL;
	printk(KERN_WARNING "SELinux: mount invalid.  Same superblock, different "
806
	       "security settings for (dev %s, type %s)\n", sb->s_id, name);
807
	goto out;
L
Linus Torvalds 已提交
808 809
}

810 811 812 813 814 815 816 817 818 819 820 821 822 823 824 825 826 827 828 829 830 831 832 833 834 835 836 837 838 839 840
static int selinux_cmp_sb_context(const struct super_block *oldsb,
				    const struct super_block *newsb)
{
	struct superblock_security_struct *old = oldsb->s_security;
	struct superblock_security_struct *new = newsb->s_security;
	char oldflags = old->flags & SE_MNTMASK;
	char newflags = new->flags & SE_MNTMASK;

	if (oldflags != newflags)
		goto mismatch;
	if ((oldflags & FSCONTEXT_MNT) && old->sid != new->sid)
		goto mismatch;
	if ((oldflags & CONTEXT_MNT) && old->mntpoint_sid != new->mntpoint_sid)
		goto mismatch;
	if ((oldflags & DEFCONTEXT_MNT) && old->def_sid != new->def_sid)
		goto mismatch;
	if (oldflags & ROOTCONTEXT_MNT) {
		struct inode_security_struct *oldroot = oldsb->s_root->d_inode->i_security;
		struct inode_security_struct *newroot = newsb->s_root->d_inode->i_security;
		if (oldroot->sid != newroot->sid)
			goto mismatch;
	}
	return 0;
mismatch:
	printk(KERN_WARNING "SELinux: mount invalid.  Same superblock, "
			    "different security settings for (dev %s, "
			    "type %s)\n", newsb->s_id, newsb->s_type->name);
	return -EBUSY;
}

static int selinux_sb_clone_mnt_opts(const struct super_block *oldsb,
841
					struct super_block *newsb)
L
Linus Torvalds 已提交
842
{
843 844
	const struct superblock_security_struct *oldsbsec = oldsb->s_security;
	struct superblock_security_struct *newsbsec = newsb->s_security;
L
Linus Torvalds 已提交
845

846 847 848
	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
849

850 851
	/*
	 * if the parent was able to be mounted it clearly had no special lsm
852
	 * mount options.  thus we can safely deal with this superblock later
853
	 */
854
	if (!ss_initialized)
855
		return 0;
856 857

	/* how can we clone if the old one wasn't set up?? */
858
	BUG_ON(!(oldsbsec->flags & SE_SBINITIALIZED));
859

860
	/* if fs is reusing a sb, make sure that the contexts match */
861
	if (newsbsec->flags & SE_SBINITIALIZED)
862
		return selinux_cmp_sb_context(oldsb, newsb);
863

864 865 866 867 868 869 870 871 872 873 874 875 876 877 878 879 880 881 882
	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
883
	}
884 885 886 887 888
	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
889

890
		newisec->sid = oldisec->sid;
L
Linus Torvalds 已提交
891 892
	}

893 894
	sb_finish_set_opts(newsb);
	mutex_unlock(&newsbsec->lock);
895
	return 0;
896 897
}

898 899
static int selinux_parse_opts_str(char *options,
				  struct security_mnt_opts *opts)
900
{
901
	char *p;
902 903
	char *context = NULL, *defcontext = NULL;
	char *fscontext = NULL, *rootcontext = NULL;
904
	int rc, num_mnt_opts = 0;
L
Linus Torvalds 已提交
905

906
	opts->num_mnt_opts = 0;
L
Linus Torvalds 已提交
907

908 909 910 911
	/* Standard string-based options. */
	while ((p = strsep(&options, "|")) != NULL) {
		int token;
		substring_t args[MAX_OPT_ARGS];
L
Linus Torvalds 已提交
912

913 914
		if (!*p)
			continue;
L
Linus Torvalds 已提交
915

916
		token = match_token(p, tokens, args);
L
Linus Torvalds 已提交
917

918 919 920 921 922 923 924 925 926 927 928 929 930 931 932 933 934 935 936 937 938 939 940 941 942 943 944 945 946 947 948 949 950 951 952 953 954 955 956 957 958 959 960 961 962 963 964 965 966 967 968 969
		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;
970 971
		case Opt_labelsupport:
			break;
972 973 974 975
		default:
			rc = -EINVAL;
			printk(KERN_WARNING "SELinux:  unknown mount option\n");
			goto out_err;
L
Linus Torvalds 已提交
976 977 978

		}
	}
979

980 981 982 983 984 985 986 987 988 989 990
	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;
	}

991
	if (fscontext) {
992 993
		opts->mnt_opts[num_mnt_opts] = fscontext;
		opts->mnt_opts_flags[num_mnt_opts++] = FSCONTEXT_MNT;
994 995
	}
	if (context) {
996 997
		opts->mnt_opts[num_mnt_opts] = context;
		opts->mnt_opts_flags[num_mnt_opts++] = CONTEXT_MNT;
998 999
	}
	if (rootcontext) {
1000 1001
		opts->mnt_opts[num_mnt_opts] = rootcontext;
		opts->mnt_opts_flags[num_mnt_opts++] = ROOTCONTEXT_MNT;
1002 1003
	}
	if (defcontext) {
1004 1005
		opts->mnt_opts[num_mnt_opts] = defcontext;
		opts->mnt_opts_flags[num_mnt_opts++] = DEFCONTEXT_MNT;
1006 1007
	}

1008 1009 1010
	opts->num_mnt_opts = num_mnt_opts;
	return 0;

1011 1012 1013 1014 1015
out_err:
	kfree(context);
	kfree(defcontext);
	kfree(fscontext);
	kfree(rootcontext);
L
Linus Torvalds 已提交
1016 1017
	return rc;
}
1018 1019 1020 1021 1022 1023 1024 1025 1026 1027 1028 1029 1030 1031 1032 1033 1034 1035 1036 1037 1038
/*
 * 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:
1039
	rc = selinux_set_mnt_opts(sb, &opts, 0, NULL);
1040 1041 1042 1043 1044

out_err:
	security_free_mnt_opts(&opts);
	return rc;
}
L
Linus Torvalds 已提交
1045

A
Adrian Bunk 已提交
1046 1047
static void selinux_write_opts(struct seq_file *m,
			       struct security_mnt_opts *opts)
1048 1049 1050 1051 1052
{
	int i;
	char *prefix;

	for (i = 0; i < opts->num_mnt_opts; i++) {
1053 1054 1055 1056 1057 1058
		char *has_comma;

		if (opts->mnt_opts[i])
			has_comma = strchr(opts->mnt_opts[i], ',');
		else
			has_comma = NULL;
1059 1060 1061 1062 1063 1064 1065 1066 1067 1068 1069 1070 1071 1072

		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;
1073
		case SBLABEL_MNT:
1074 1075 1076
			seq_putc(m, ',');
			seq_puts(m, LABELSUPP_STR);
			continue;
1077 1078
		default:
			BUG();
1079
			return;
1080 1081 1082 1083 1084 1085 1086 1087 1088 1089 1090 1091 1092 1093 1094 1095 1096 1097
		};
		/* 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);
1098 1099 1100 1101
	if (rc) {
		/* before policy load we may get EINVAL, don't show anything */
		if (rc == -EINVAL)
			rc = 0;
1102
		return rc;
1103
	}
1104 1105 1106 1107 1108 1109 1110 1111

	selinux_write_opts(m, &opts);

	security_free_mnt_opts(&opts);

	return rc;
}

L
Linus Torvalds 已提交
1112 1113 1114 1115 1116 1117 1118 1119 1120 1121 1122 1123 1124 1125 1126 1127 1128 1129 1130 1131 1132 1133 1134
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;
}

1135 1136 1137 1138 1139 1140 1141 1142 1143 1144
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
1145 1146 1147 1148 1149 1150 1151 1152 1153 1154 1155 1156 1157 1158 1159 1160
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:
1161 1162 1163 1164
			if (default_protocol_stream(protocol))
				return SECCLASS_TCP_SOCKET;
			else
				return SECCLASS_RAWIP_SOCKET;
L
Linus Torvalds 已提交
1165
		case SOCK_DGRAM:
1166 1167 1168 1169
			if (default_protocol_dgram(protocol))
				return SECCLASS_UDP_SOCKET;
			else
				return SECCLASS_RAWIP_SOCKET;
J
James Morris 已提交
1170 1171
		case SOCK_DCCP:
			return SECCLASS_DCCP_SOCKET;
1172
		default:
L
Linus Torvalds 已提交
1173 1174 1175 1176 1177 1178 1179 1180 1181
			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;
1182
		case NETLINK_SOCK_DIAG:
L
Linus Torvalds 已提交
1183 1184 1185 1186 1187 1188 1189 1190 1191 1192 1193 1194 1195
			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;
1196 1197
		case NETLINK_KOBJECT_UEVENT:
			return SECCLASS_NETLINK_KOBJECT_UEVENT_SOCKET;
L
Linus Torvalds 已提交
1198 1199 1200 1201 1202 1203 1204
		default:
			return SECCLASS_NETLINK_SOCKET;
		}
	case PF_PACKET:
		return SECCLASS_PACKET_SOCKET;
	case PF_KEY:
		return SECCLASS_KEY_SOCKET;
1205 1206
	case PF_APPLETALK:
		return SECCLASS_APPLETALK_SOCKET;
L
Linus Torvalds 已提交
1207 1208 1209 1210 1211 1212
	}

	return SECCLASS_SOCKET;
}

#ifdef CONFIG_PROC_FS
1213
static int selinux_proc_get_sid(struct dentry *dentry,
L
Linus Torvalds 已提交
1214 1215 1216
				u16 tclass,
				u32 *sid)
{
1217 1218
	int rc;
	char *buffer, *path;
L
Linus Torvalds 已提交
1219

1220
	buffer = (char *)__get_free_page(GFP_KERNEL);
L
Linus Torvalds 已提交
1221 1222 1223
	if (!buffer)
		return -ENOMEM;

1224 1225 1226 1227 1228 1229 1230 1231 1232 1233 1234 1235
	path = dentry_path_raw(dentry, buffer, PAGE_SIZE);
	if (IS_ERR(path))
		rc = PTR_ERR(path);
	else {
		/* each process gets a /proc/PID/ entry. Strip off the
		 * PID part to get a valid selinux labeling.
		 * e.g. /proc/1/net/rpc/nfs -> /net/rpc/nfs */
		while (path[1] >= '0' && path[1] <= '9') {
			path[1] = '/';
			path++;
		}
		rc = security_genfs_sid("proc", path, tclass, sid);
L
Linus Torvalds 已提交
1236 1237 1238 1239 1240
	}
	free_page((unsigned long)buffer);
	return rc;
}
#else
1241
static int selinux_proc_get_sid(struct dentry *dentry,
L
Linus Torvalds 已提交
1242 1243 1244 1245 1246 1247 1248 1249 1250 1251 1252 1253 1254 1255 1256 1257 1258 1259 1260 1261 1262 1263
				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;

1264
	mutex_lock(&isec->lock);
L
Linus Torvalds 已提交
1265
	if (isec->initialized)
1266
		goto out_unlock;
L
Linus Torvalds 已提交
1267 1268

	sbsec = inode->i_sb->s_security;
1269
	if (!(sbsec->flags & SE_SBINITIALIZED)) {
L
Linus Torvalds 已提交
1270 1271 1272 1273 1274 1275 1276
		/* 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);
1277
		goto out_unlock;
L
Linus Torvalds 已提交
1278 1279 1280
	}

	switch (sbsec->behavior) {
1281 1282
	case SECURITY_FS_USE_NATIVE:
		break;
L
Linus Torvalds 已提交
1283 1284 1285 1286 1287 1288 1289 1290 1291 1292 1293 1294 1295 1296 1297 1298
	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) {
1299 1300 1301 1302 1303 1304 1305 1306 1307
			/*
			 * this is can be hit on boot when a file is accessed
			 * before the policy is loaded.  When we load policy we
			 * may find inodes that have no dentry on the
			 * sbsec->isec_head list.  No reason to complain as these
			 * will get fixed up the next time we go through
			 * inode_doinit with a dentry, before these inodes could
			 * be used again by userspace.
			 */
1308
			goto out_unlock;
L
Linus Torvalds 已提交
1309 1310 1311
		}

		len = INITCONTEXTLEN;
1312
		context = kmalloc(len+1, GFP_NOFS);
L
Linus Torvalds 已提交
1313 1314 1315
		if (!context) {
			rc = -ENOMEM;
			dput(dentry);
1316
			goto out_unlock;
L
Linus Torvalds 已提交
1317
		}
1318
		context[len] = '\0';
L
Linus Torvalds 已提交
1319 1320 1321
		rc = inode->i_op->getxattr(dentry, XATTR_NAME_SELINUX,
					   context, len);
		if (rc == -ERANGE) {
1322 1323
			kfree(context);

L
Linus Torvalds 已提交
1324 1325 1326 1327 1328
			/* 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);
1329
				goto out_unlock;
L
Linus Torvalds 已提交
1330 1331
			}
			len = rc;
1332
			context = kmalloc(len+1, GFP_NOFS);
L
Linus Torvalds 已提交
1333 1334 1335
			if (!context) {
				rc = -ENOMEM;
				dput(dentry);
1336
				goto out_unlock;
L
Linus Torvalds 已提交
1337
			}
1338
			context[len] = '\0';
L
Linus Torvalds 已提交
1339 1340 1341 1342 1343 1344 1345
			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
1346
				printk(KERN_WARNING "SELinux: %s:  getxattr returned "
1347
				       "%d for dev=%s ino=%ld\n", __func__,
L
Linus Torvalds 已提交
1348 1349
				       -rc, inode->i_sb->s_id, inode->i_ino);
				kfree(context);
1350
				goto out_unlock;
L
Linus Torvalds 已提交
1351 1352 1353 1354 1355
			}
			/* Map ENODATA to the default file SID */
			sid = sbsec->def_sid;
			rc = 0;
		} else {
1356
			rc = security_context_to_sid_default(context, rc, &sid,
1357 1358
							     sbsec->def_sid,
							     GFP_NOFS);
L
Linus Torvalds 已提交
1359
			if (rc) {
1360 1361 1362 1363 1364 1365 1366 1367 1368 1369 1370 1371 1372
				char *dev = inode->i_sb->s_id;
				unsigned long ino = inode->i_ino;

				if (rc == -EINVAL) {
					if (printk_ratelimit())
						printk(KERN_NOTICE "SELinux: inode=%lu on dev=%s was found to have an invalid "
							"context=%s.  This indicates you may need to relabel the inode or the "
							"filesystem in question.\n", ino, dev, context);
				} else {
					printk(KERN_WARNING "SELinux: %s:  context_to_sid(%s) "
					       "returned %d for dev=%s ino=%ld\n",
					       __func__, context, -rc, dev, ino);
				}
L
Linus Torvalds 已提交
1373 1374 1375 1376 1377 1378 1379 1380 1381 1382 1383 1384 1385 1386 1387 1388 1389 1390
				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);
1391 1392
		rc = security_transition_sid(isec->task_sid, sbsec->sid,
					     isec->sclass, NULL, &sid);
L
Linus Torvalds 已提交
1393
		if (rc)
1394
			goto out_unlock;
L
Linus Torvalds 已提交
1395 1396
		isec->sid = sid;
		break;
1397 1398 1399
	case SECURITY_FS_USE_MNTPOINT:
		isec->sid = sbsec->mntpoint_sid;
		break;
L
Linus Torvalds 已提交
1400
	default:
1401
		/* Default to the fs superblock SID. */
L
Linus Torvalds 已提交
1402 1403
		isec->sid = sbsec->sid;

1404
		if ((sbsec->flags & SE_SBPROC) && !S_ISLNK(inode->i_mode)) {
1405
			if (opt_dentry) {
L
Linus Torvalds 已提交
1406
				isec->sclass = inode_mode_to_security_class(inode->i_mode);
1407
				rc = selinux_proc_get_sid(opt_dentry,
L
Linus Torvalds 已提交
1408 1409 1410
							  isec->sclass,
							  &sid);
				if (rc)
1411
					goto out_unlock;
L
Linus Torvalds 已提交
1412 1413 1414 1415 1416 1417 1418 1419
				isec->sid = sid;
			}
		}
		break;
	}

	isec->initialized = 1;

1420 1421
out_unlock:
	mutex_unlock(&isec->lock);
L
Linus Torvalds 已提交
1422 1423 1424 1425 1426 1427 1428 1429 1430 1431 1432 1433 1434 1435 1436 1437 1438 1439 1440 1441 1442 1443 1444 1445 1446 1447 1448 1449 1450 1451 1452 1453 1454
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
1455 1456 1457 1458 1459 1460 1461 1462 1463 1464 1465 1466 1467
/*
 * 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);
}

1468
/*
1469
 * Check permission between a pair of tasks, e.g. signal checks,
1470 1471
 * fork check, ptrace check, etc.
 * tsk1 is the actor and tsk2 is the target
1472
 * - this uses the default subjective creds of tsk1
1473 1474 1475
 */
static int task_has_perm(const struct task_struct *tsk1,
			 const struct task_struct *tsk2,
L
Linus Torvalds 已提交
1476 1477
			 u32 perms)
{
1478 1479
	const struct task_security_struct *__tsec1, *__tsec2;
	u32 sid1, sid2;
L
Linus Torvalds 已提交
1480

1481 1482 1483 1484 1485
	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
1486 1487
}

1488 1489 1490 1491 1492 1493 1494 1495 1496 1497 1498 1499 1500 1501 1502 1503
/*
 * 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);
}

1504 1505 1506 1507
#if CAP_LAST_CAP > 63
#error Fix SELinux to handle capabilities > 63.
#endif

L
Linus Torvalds 已提交
1508
/* Check whether a task is allowed to use a capability. */
1509
static int cred_has_capability(const struct cred *cred,
1510
			       int cap, int audit)
L
Linus Torvalds 已提交
1511
{
1512
	struct common_audit_data ad;
1513
	struct av_decision avd;
1514
	u16 sclass;
1515
	u32 sid = cred_sid(cred);
1516
	u32 av = CAP_TO_MASK(cap);
1517
	int rc;
L
Linus Torvalds 已提交
1518

1519
	ad.type = LSM_AUDIT_DATA_CAP;
L
Linus Torvalds 已提交
1520 1521
	ad.u.cap = cap;

1522 1523 1524 1525 1526 1527 1528 1529 1530 1531 1532
	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();
1533
		return -EINVAL;
1534
	}
1535

1536
	rc = avc_has_perm_noaudit(sid, sid, sclass, av, 0, &avd);
1537
	if (audit == SECURITY_CAP_AUDIT) {
1538
		int rc2 = avc_audit(sid, sid, sclass, av, &avd, rc, &ad);
1539 1540 1541
		if (rc2)
			return rc2;
	}
1542
	return rc;
L
Linus Torvalds 已提交
1543 1544 1545 1546 1547 1548
}

/* Check whether a task is allowed to use a system operation. */
static int task_has_system(struct task_struct *tsk,
			   u32 perms)
{
1549
	u32 sid = task_sid(tsk);
L
Linus Torvalds 已提交
1550

1551
	return avc_has_perm(sid, SECINITSID_KERNEL,
L
Linus Torvalds 已提交
1552 1553 1554 1555 1556 1557
			    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). */
1558
static int inode_has_perm(const struct cred *cred,
L
Linus Torvalds 已提交
1559 1560
			  struct inode *inode,
			  u32 perms,
1561
			  struct common_audit_data *adp)
L
Linus Torvalds 已提交
1562 1563
{
	struct inode_security_struct *isec;
1564
	u32 sid;
L
Linus Torvalds 已提交
1565

1566 1567
	validate_creds(cred);

1568
	if (unlikely(IS_PRIVATE(inode)))
1569 1570
		return 0;

1571
	sid = cred_sid(cred);
L
Linus Torvalds 已提交
1572 1573
	isec = inode->i_security;

1574
	return avc_has_perm(sid, isec->sid, isec->sclass, perms, adp);
L
Linus Torvalds 已提交
1575 1576 1577 1578 1579
}

/* 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. */
1580
static inline int dentry_has_perm(const struct cred *cred,
L
Linus Torvalds 已提交
1581 1582 1583 1584
				  struct dentry *dentry,
				  u32 av)
{
	struct inode *inode = dentry->d_inode;
1585
	struct common_audit_data ad;
1586

1587
	ad.type = LSM_AUDIT_DATA_DENTRY;
E
Eric Paris 已提交
1588
	ad.u.dentry = dentry;
1589
	return inode_has_perm(cred, inode, av, &ad);
E
Eric Paris 已提交
1590 1591 1592 1593 1594 1595 1596 1597 1598 1599 1600 1601
}

/* Same as inode_has_perm, but pass explicit audit data containing
   the path to help the auditing code to more easily generate the
   pathname if needed. */
static inline int path_has_perm(const struct cred *cred,
				struct path *path,
				u32 av)
{
	struct inode *inode = path->dentry->d_inode;
	struct common_audit_data ad;

1602
	ad.type = LSM_AUDIT_DATA_PATH;
E
Eric Paris 已提交
1603
	ad.u.path = *path;
1604
	return inode_has_perm(cred, inode, av, &ad);
L
Linus Torvalds 已提交
1605 1606
}

1607 1608 1609 1610 1611 1612 1613 1614 1615
/* Same as path_has_perm, but uses the inode from the file struct. */
static inline int file_path_has_perm(const struct cred *cred,
				     struct file *file,
				     u32 av)
{
	struct common_audit_data ad;

	ad.type = LSM_AUDIT_DATA_PATH;
	ad.u.path = file->f_path;
1616
	return inode_has_perm(cred, file_inode(file), av, &ad);
1617 1618
}

L
Linus Torvalds 已提交
1619 1620 1621 1622 1623 1624 1625 1626
/* 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. */
1627 1628 1629
static int file_has_perm(const struct cred *cred,
			 struct file *file,
			 u32 av)
L
Linus Torvalds 已提交
1630 1631
{
	struct file_security_struct *fsec = file->f_security;
A
Al Viro 已提交
1632
	struct inode *inode = file_inode(file);
1633
	struct common_audit_data ad;
1634
	u32 sid = cred_sid(cred);
L
Linus Torvalds 已提交
1635 1636
	int rc;

1637
	ad.type = LSM_AUDIT_DATA_PATH;
1638
	ad.u.path = file->f_path;
L
Linus Torvalds 已提交
1639

1640 1641
	if (sid != fsec->sid) {
		rc = avc_has_perm(sid, fsec->sid,
L
Linus Torvalds 已提交
1642 1643 1644 1645
				  SECCLASS_FD,
				  FD__USE,
				  &ad);
		if (rc)
1646
			goto out;
L
Linus Torvalds 已提交
1647 1648 1649
	}

	/* av is zero if only checking access to the descriptor. */
1650
	rc = 0;
L
Linus Torvalds 已提交
1651
	if (av)
1652
		rc = inode_has_perm(cred, inode, av, &ad);
L
Linus Torvalds 已提交
1653

1654 1655
out:
	return rc;
L
Linus Torvalds 已提交
1656 1657 1658 1659 1660 1661 1662
}

/* Check whether a task can create a file. */
static int may_create(struct inode *dir,
		      struct dentry *dentry,
		      u16 tclass)
{
1663
	const struct task_security_struct *tsec = current_security();
L
Linus Torvalds 已提交
1664 1665
	struct inode_security_struct *dsec;
	struct superblock_security_struct *sbsec;
1666
	u32 sid, newsid;
1667
	struct common_audit_data ad;
L
Linus Torvalds 已提交
1668 1669 1670 1671 1672
	int rc;

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

1673 1674 1675
	sid = tsec->sid;
	newsid = tsec->create_sid;

1676
	ad.type = LSM_AUDIT_DATA_DENTRY;
1677
	ad.u.dentry = dentry;
L
Linus Torvalds 已提交
1678

1679
	rc = avc_has_perm(sid, dsec->sid, SECCLASS_DIR,
L
Linus Torvalds 已提交
1680 1681 1682 1683 1684
			  DIR__ADD_NAME | DIR__SEARCH,
			  &ad);
	if (rc)
		return rc;

1685
	if (!newsid || !(sbsec->flags & SBLABEL_MNT)) {
1686 1687
		rc = security_transition_sid(sid, dsec->sid, tclass,
					     &dentry->d_name, &newsid);
L
Linus Torvalds 已提交
1688 1689 1690 1691
		if (rc)
			return rc;
	}

1692
	rc = avc_has_perm(sid, newsid, tclass, FILE__CREATE, &ad);
L
Linus Torvalds 已提交
1693 1694 1695 1696 1697 1698 1699 1700
	if (rc)
		return rc;

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

1701 1702 1703 1704
/* Check whether a task can create a key. */
static int may_create_key(u32 ksid,
			  struct task_struct *ctx)
{
1705
	u32 sid = task_sid(ctx);
1706

1707
	return avc_has_perm(sid, ksid, SECCLASS_KEY, KEY__CREATE, NULL);
1708 1709
}

1710 1711 1712
#define MAY_LINK	0
#define MAY_UNLINK	1
#define MAY_RMDIR	2
L
Linus Torvalds 已提交
1713 1714 1715 1716 1717 1718 1719 1720

/* 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;
1721
	struct common_audit_data ad;
1722
	u32 sid = current_sid();
L
Linus Torvalds 已提交
1723 1724 1725 1726 1727 1728
	u32 av;
	int rc;

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

1729
	ad.type = LSM_AUDIT_DATA_DENTRY;
1730
	ad.u.dentry = dentry;
L
Linus Torvalds 已提交
1731 1732 1733

	av = DIR__SEARCH;
	av |= (kind ? DIR__REMOVE_NAME : DIR__ADD_NAME);
1734
	rc = avc_has_perm(sid, dsec->sid, SECCLASS_DIR, av, &ad);
L
Linus Torvalds 已提交
1735 1736 1737 1738 1739 1740 1741 1742 1743 1744 1745 1746 1747 1748
	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
1749 1750
		printk(KERN_WARNING "SELinux: %s:  unrecognized kind %d\n",
			__func__, kind);
L
Linus Torvalds 已提交
1751 1752 1753
		return 0;
	}

1754
	rc = avc_has_perm(sid, isec->sid, isec->sclass, av, &ad);
L
Linus Torvalds 已提交
1755 1756 1757 1758 1759 1760 1761 1762 1763
	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;
1764
	struct common_audit_data ad;
1765
	u32 sid = current_sid();
L
Linus Torvalds 已提交
1766 1767 1768 1769 1770 1771 1772 1773 1774
	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;

1775
	ad.type = LSM_AUDIT_DATA_DENTRY;
L
Linus Torvalds 已提交
1776

1777
	ad.u.dentry = old_dentry;
1778
	rc = avc_has_perm(sid, old_dsec->sid, SECCLASS_DIR,
L
Linus Torvalds 已提交
1779 1780 1781
			  DIR__REMOVE_NAME | DIR__SEARCH, &ad);
	if (rc)
		return rc;
1782
	rc = avc_has_perm(sid, old_isec->sid,
L
Linus Torvalds 已提交
1783 1784 1785 1786
			  old_isec->sclass, FILE__RENAME, &ad);
	if (rc)
		return rc;
	if (old_is_dir && new_dir != old_dir) {
1787
		rc = avc_has_perm(sid, old_isec->sid,
L
Linus Torvalds 已提交
1788 1789 1790 1791 1792
				  old_isec->sclass, DIR__REPARENT, &ad);
		if (rc)
			return rc;
	}

1793
	ad.u.dentry = new_dentry;
L
Linus Torvalds 已提交
1794 1795 1796
	av = DIR__ADD_NAME | DIR__SEARCH;
	if (new_dentry->d_inode)
		av |= DIR__REMOVE_NAME;
1797
	rc = avc_has_perm(sid, new_dsec->sid, SECCLASS_DIR, av, &ad);
L
Linus Torvalds 已提交
1798 1799 1800 1801 1802
	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);
1803
		rc = avc_has_perm(sid, new_isec->sid,
L
Linus Torvalds 已提交
1804 1805 1806 1807 1808 1809 1810 1811 1812 1813
				  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. */
1814
static int superblock_has_perm(const struct cred *cred,
L
Linus Torvalds 已提交
1815 1816
			       struct super_block *sb,
			       u32 perms,
1817
			       struct common_audit_data *ad)
L
Linus Torvalds 已提交
1818 1819
{
	struct superblock_security_struct *sbsec;
1820
	u32 sid = cred_sid(cred);
L
Linus Torvalds 已提交
1821 1822

	sbsec = sb->s_security;
1823
	return avc_has_perm(sid, sbsec->sid, SECCLASS_FILESYSTEM, perms, ad);
L
Linus Torvalds 已提交
1824 1825 1826 1827 1828 1829 1830
}

/* 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;

A
Al Viro 已提交
1831
	if (!S_ISDIR(mode)) {
L
Linus Torvalds 已提交
1832 1833 1834 1835 1836 1837 1838 1839 1840 1841 1842 1843 1844 1845 1846 1847 1848 1849 1850 1851 1852 1853
		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;
}

1854 1855 1856 1857 1858 1859 1860 1861 1862 1863 1864 1865 1866 1867 1868 1869 1870 1871 1872 1873 1874 1875 1876
/* 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
1877
/*
1878
 * Convert a file to an access vector and include the correct open
E
Eric Paris 已提交
1879 1880
 * open permission.
 */
1881
static inline u32 open_file_to_av(struct file *file)
E
Eric Paris 已提交
1882
{
1883
	u32 av = file_to_av(file);
E
Eric Paris 已提交
1884

1885 1886 1887
	if (selinux_policycap_openperm)
		av |= FILE__OPEN;

E
Eric Paris 已提交
1888 1889 1890
	return av;
}

L
Linus Torvalds 已提交
1891 1892
/* Hook functions begin here. */

1893
static int selinux_ptrace_access_check(struct task_struct *child,
1894
				     unsigned int mode)
L
Linus Torvalds 已提交
1895 1896 1897
{
	int rc;

1898
	rc = cap_ptrace_access_check(child, mode);
L
Linus Torvalds 已提交
1899 1900 1901
	if (rc)
		return rc;

1902
	if (mode & PTRACE_MODE_READ) {
1903 1904 1905
		u32 sid = current_sid();
		u32 csid = task_sid(child);
		return avc_has_perm(sid, csid, SECCLASS_FILE, FILE__READ, NULL);
1906 1907
	}

1908
	return current_has_perm(child, PROCESS__PTRACE);
1909 1910 1911 1912 1913 1914
}

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

1915
	rc = cap_ptrace_traceme(parent);
1916 1917 1918 1919
	if (rc)
		return rc;

	return task_has_perm(parent, current, PROCESS__PTRACE);
L
Linus Torvalds 已提交
1920 1921 1922
}

static int selinux_capget(struct task_struct *target, kernel_cap_t *effective,
1923
			  kernel_cap_t *inheritable, kernel_cap_t *permitted)
L
Linus Torvalds 已提交
1924 1925 1926
{
	int error;

1927
	error = current_has_perm(target, PROCESS__GETCAP);
L
Linus Torvalds 已提交
1928 1929 1930
	if (error)
		return error;

1931
	return cap_capget(target, effective, inheritable, permitted);
L
Linus Torvalds 已提交
1932 1933
}

D
David Howells 已提交
1934 1935 1936 1937
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
1938 1939 1940
{
	int error;

1941
	error = cap_capset(new, old,
D
David Howells 已提交
1942
				      effective, inheritable, permitted);
L
Linus Torvalds 已提交
1943 1944 1945
	if (error)
		return error;

D
David Howells 已提交
1946
	return cred_has_perm(old, new, PROCESS__SETCAP);
L
Linus Torvalds 已提交
1947 1948
}

1949 1950 1951 1952 1953 1954 1955 1956 1957 1958
/*
 * (This comment used to live with the selinux_task_setuid hook,
 * which was removed).
 *
 * 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.
 */

1959 1960
static int selinux_capable(const struct cred *cred, struct user_namespace *ns,
			   int cap, int audit)
L
Linus Torvalds 已提交
1961 1962 1963
{
	int rc;

1964
	rc = cap_capable(cred, ns, cap, audit);
L
Linus Torvalds 已提交
1965 1966 1967
	if (rc)
		return rc;

1968
	return cred_has_capability(cred, cap, audit);
L
Linus Torvalds 已提交
1969 1970 1971 1972
}

static int selinux_quotactl(int cmds, int type, int id, struct super_block *sb)
{
1973
	const struct cred *cred = current_cred();
L
Linus Torvalds 已提交
1974 1975 1976 1977 1978 1979
	int rc = 0;

	if (!sb)
		return 0;

	switch (cmds) {
1980 1981 1982 1983 1984
	case Q_SYNC:
	case Q_QUOTAON:
	case Q_QUOTAOFF:
	case Q_SETINFO:
	case Q_SETQUOTA:
1985
		rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAMOD, NULL);
1986 1987 1988 1989
		break;
	case Q_GETFMT:
	case Q_GETINFO:
	case Q_GETQUOTA:
1990
		rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAGET, NULL);
1991 1992 1993 1994
		break;
	default:
		rc = 0;  /* let the kernel handle invalid cmds */
		break;
L
Linus Torvalds 已提交
1995 1996 1997 1998 1999 2000
	}
	return rc;
}

static int selinux_quota_on(struct dentry *dentry)
{
2001 2002
	const struct cred *cred = current_cred();

E
Eric Paris 已提交
2003
	return dentry_has_perm(cred, dentry, FILE__QUOTAON);
L
Linus Torvalds 已提交
2004 2005
}

2006
static int selinux_syslog(int type)
L
Linus Torvalds 已提交
2007 2008 2009 2010
{
	int rc;

	switch (type) {
2011 2012
	case SYSLOG_ACTION_READ_ALL:	/* Read last kernel messages */
	case SYSLOG_ACTION_SIZE_BUFFER:	/* Return size of the log buffer */
2013 2014
		rc = task_has_system(current, SYSTEM__SYSLOG_READ);
		break;
2015 2016 2017 2018
	case SYSLOG_ACTION_CONSOLE_OFF:	/* Disable logging to console */
	case SYSLOG_ACTION_CONSOLE_ON:	/* Enable logging to console */
	/* Set level of messages printed to console */
	case SYSLOG_ACTION_CONSOLE_LEVEL:
2019 2020
		rc = task_has_system(current, SYSTEM__SYSLOG_CONSOLE);
		break;
2021 2022 2023 2024 2025
	case SYSLOG_ACTION_CLOSE:	/* Close log */
	case SYSLOG_ACTION_OPEN:	/* Open log */
	case SYSLOG_ACTION_READ:	/* Read from log */
	case SYSLOG_ACTION_READ_CLEAR:	/* Read/clear last kernel messages */
	case SYSLOG_ACTION_CLEAR:	/* Clear ring buffer */
2026 2027 2028
	default:
		rc = task_has_system(current, SYSTEM__SYSLOG_MOD);
		break;
L
Linus Torvalds 已提交
2029 2030 2031 2032 2033 2034 2035 2036 2037 2038 2039 2040
	}
	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.
 *
 * Do not audit the selinux permission check, as this is applied to all
 * processes that allocate mappings.
 */
2041
static int selinux_vm_enough_memory(struct mm_struct *mm, long pages)
L
Linus Torvalds 已提交
2042 2043 2044
{
	int rc, cap_sys_admin = 0;

2045
	rc = selinux_capable(current_cred(), &init_user_ns, CAP_SYS_ADMIN,
2046
			     SECURITY_CAP_NOAUDIT);
L
Linus Torvalds 已提交
2047 2048 2049
	if (rc == 0)
		cap_sys_admin = 1;

2050
	return __vm_enough_memory(mm, pages, cap_sys_admin);
L
Linus Torvalds 已提交
2051 2052 2053 2054
}

/* binprm security operations */

2055
static int selinux_bprm_set_creds(struct linux_binprm *bprm)
L
Linus Torvalds 已提交
2056
{
2057 2058
	const struct task_security_struct *old_tsec;
	struct task_security_struct *new_tsec;
L
Linus Torvalds 已提交
2059
	struct inode_security_struct *isec;
2060
	struct common_audit_data ad;
A
Al Viro 已提交
2061
	struct inode *inode = file_inode(bprm->file);
L
Linus Torvalds 已提交
2062 2063
	int rc;

2064
	rc = cap_bprm_set_creds(bprm);
L
Linus Torvalds 已提交
2065 2066 2067
	if (rc)
		return rc;

2068 2069 2070
	/* SELinux context only depends on initial program or script and not
	 * the script interpreter */
	if (bprm->cred_prepared)
L
Linus Torvalds 已提交
2071 2072
		return 0;

2073 2074
	old_tsec = current_security();
	new_tsec = bprm->cred->security;
L
Linus Torvalds 已提交
2075 2076 2077
	isec = inode->i_security;

	/* Default to the current task SID. */
2078 2079
	new_tsec->sid = old_tsec->sid;
	new_tsec->osid = old_tsec->sid;
L
Linus Torvalds 已提交
2080

2081
	/* Reset fs, key, and sock SIDs on execve. */
2082 2083 2084
	new_tsec->create_sid = 0;
	new_tsec->keycreate_sid = 0;
	new_tsec->sockcreate_sid = 0;
L
Linus Torvalds 已提交
2085

2086 2087
	if (old_tsec->exec_sid) {
		new_tsec->sid = old_tsec->exec_sid;
L
Linus Torvalds 已提交
2088
		/* Reset exec SID on execve. */
2089
		new_tsec->exec_sid = 0;
2090 2091 2092 2093 2094 2095 2096

		/*
		 * Minimize confusion: if no_new_privs and a transition is
		 * explicitly requested, then fail the exec.
		 */
		if (bprm->unsafe & LSM_UNSAFE_NO_NEW_PRIVS)
			return -EPERM;
L
Linus Torvalds 已提交
2097 2098
	} else {
		/* Check for a default transition on this program. */
2099
		rc = security_transition_sid(old_tsec->sid, isec->sid,
2100 2101
					     SECCLASS_PROCESS, NULL,
					     &new_tsec->sid);
L
Linus Torvalds 已提交
2102 2103 2104 2105
		if (rc)
			return rc;
	}

2106
	ad.type = LSM_AUDIT_DATA_PATH;
2107
	ad.u.path = bprm->file->f_path;
L
Linus Torvalds 已提交
2108

2109 2110
	if ((bprm->file->f_path.mnt->mnt_flags & MNT_NOSUID) ||
	    (bprm->unsafe & LSM_UNSAFE_NO_NEW_PRIVS))
2111
		new_tsec->sid = old_tsec->sid;
L
Linus Torvalds 已提交
2112

2113 2114
	if (new_tsec->sid == old_tsec->sid) {
		rc = avc_has_perm(old_tsec->sid, isec->sid,
L
Linus Torvalds 已提交
2115 2116 2117 2118 2119
				  SECCLASS_FILE, FILE__EXECUTE_NO_TRANS, &ad);
		if (rc)
			return rc;
	} else {
		/* Check permissions for the transition. */
2120
		rc = avc_has_perm(old_tsec->sid, new_tsec->sid,
L
Linus Torvalds 已提交
2121 2122 2123 2124
				  SECCLASS_PROCESS, PROCESS__TRANSITION, &ad);
		if (rc)
			return rc;

2125
		rc = avc_has_perm(new_tsec->sid, isec->sid,
L
Linus Torvalds 已提交
2126 2127 2128 2129
				  SECCLASS_FILE, FILE__ENTRYPOINT, &ad);
		if (rc)
			return rc;

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();
2148
			tracer = ptrace_parent(current);
2149 2150 2151 2152 2153 2154 2155 2156 2157 2158 2159 2160 2161 2162
			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
2163

2164 2165
		/* Clear any possibly unsafe personality bits on exec: */
		bprm->per_clear |= PER_CLEAR_ON_SETID;
L
Linus Torvalds 已提交
2166 2167 2168 2169 2170
	}

	return 0;
}

2171
static int selinux_bprm_secureexec(struct linux_binprm *bprm)
L
Linus Torvalds 已提交
2172
{
2173
	const struct task_security_struct *tsec = current_security();
2174
	u32 sid, osid;
L
Linus Torvalds 已提交
2175 2176
	int atsecure = 0;

2177 2178 2179 2180
	sid = tsec->sid;
	osid = tsec->osid;

	if (osid != sid) {
L
Linus Torvalds 已提交
2181 2182 2183
		/* Enable secure mode for SIDs transitions unless
		   the noatsecure permission is granted between
		   the two SIDs, i.e. ahp returns 0. */
2184
		atsecure = avc_has_perm(osid, sid,
2185 2186
					SECCLASS_PROCESS,
					PROCESS__NOATSECURE, NULL);
L
Linus Torvalds 已提交
2187 2188
	}

2189
	return (atsecure || cap_bprm_secureexec(bprm));
L
Linus Torvalds 已提交
2190 2191
}

A
Al Viro 已提交
2192 2193 2194 2195 2196
static int match_file(const void *p, struct file *file, unsigned fd)
{
	return file_has_perm(p, file, file_to_av(file)) ? fd + 1 : 0;
}

L
Linus Torvalds 已提交
2197
/* Derived from fs/exec.c:flush_old_files. */
2198 2199
static inline void flush_unauthorized_files(const struct cred *cred,
					    struct files_struct *files)
L
Linus Torvalds 已提交
2200 2201
{
	struct file *file, *devnull = NULL;
2202
	struct tty_struct *tty;
2203
	int drop_tty = 0;
A
Al Viro 已提交
2204
	unsigned n;
L
Linus Torvalds 已提交
2205

2206
	tty = get_current_tty();
L
Linus Torvalds 已提交
2207
	if (tty) {
N
Nick Piggin 已提交
2208
		spin_lock(&tty_files_lock);
2209
		if (!list_empty(&tty->tty_files)) {
N
Nick Piggin 已提交
2210
			struct tty_file_private *file_priv;
2211

L
Linus Torvalds 已提交
2212
			/* Revalidate access to controlling tty.
2213 2214 2215 2216
			   Use file_path_has_perm on the tty path 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. */
N
Nick Piggin 已提交
2217 2218 2219
			file_priv = list_first_entry(&tty->tty_files,
						struct tty_file_private, list);
			file = file_priv->file;
2220
			if (file_path_has_perm(cred, file, FILE__READ | FILE__WRITE))
2221
				drop_tty = 1;
L
Linus Torvalds 已提交
2222
		}
N
Nick Piggin 已提交
2223
		spin_unlock(&tty_files_lock);
A
Alan Cox 已提交
2224
		tty_kref_put(tty);
L
Linus Torvalds 已提交
2225
	}
2226 2227 2228
	/* Reset controlling tty. */
	if (drop_tty)
		no_tty();
L
Linus Torvalds 已提交
2229 2230

	/* Revalidate access to inherited open files. */
A
Al Viro 已提交
2231 2232 2233
	n = iterate_fd(files, 0, match_file, cred);
	if (!n) /* none found? */
		return;
L
Linus Torvalds 已提交
2234

A
Al Viro 已提交
2235
	devnull = dentry_open(&selinux_null, O_RDWR, cred);
A
Al Viro 已提交
2236 2237 2238 2239 2240 2241 2242
	if (IS_ERR(devnull))
		devnull = NULL;
	/* replace all the matching ones with this */
	do {
		replace_fd(n - 1, devnull, 0);
	} while ((n = iterate_fd(files, n, match_file, cred)) != 0);
	if (devnull)
A
Al Viro 已提交
2243
		fput(devnull);
L
Linus Torvalds 已提交
2244 2245
}

2246 2247 2248 2249
/*
 * 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
2250
{
2251 2252 2253
	struct task_security_struct *new_tsec;
	struct rlimit *rlim, *initrlim;
	int rc, i;
D
David Howells 已提交
2254

2255 2256 2257
	new_tsec = bprm->cred->security;
	if (new_tsec->sid == new_tsec->osid)
		return;
L
Linus Torvalds 已提交
2258

2259 2260
	/* Close files for which the new task SID is not authorized. */
	flush_unauthorized_files(bprm->cred, current->files);
R
Roland McGrath 已提交
2261

2262 2263
	/* Always clear parent death signal on SID transitions. */
	current->pdeath_signal = 0;
R
Roland McGrath 已提交
2264

2265 2266 2267 2268 2269 2270 2271 2272 2273 2274 2275 2276 2277
	/* 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) {
2278 2279
		/* protect against do_prlimit() */
		task_lock(current);
2280 2281 2282 2283
		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
2284
		}
2285 2286
		task_unlock(current);
		update_rlimit_cpu(current, rlimit(RLIMIT_CPU));
L
Linus Torvalds 已提交
2287 2288 2289 2290
	}
}

/*
2291 2292
 * Clean up the process immediately after the installation of new credentials
 * due to exec
L
Linus Torvalds 已提交
2293
 */
2294
static void selinux_bprm_committed_creds(struct linux_binprm *bprm)
L
Linus Torvalds 已提交
2295
{
2296
	const struct task_security_struct *tsec = current_security();
L
Linus Torvalds 已提交
2297
	struct itimerval itimer;
2298
	u32 osid, sid;
L
Linus Torvalds 已提交
2299 2300
	int rc, i;

2301 2302 2303 2304
	osid = tsec->osid;
	sid = tsec->sid;

	if (sid == osid)
L
Linus Torvalds 已提交
2305 2306
		return;

2307 2308 2309 2310 2311 2312 2313 2314
	/* 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
2315 2316 2317 2318 2319
	if (rc) {
		memset(&itimer, 0, sizeof itimer);
		for (i = 0; i < 3; i++)
			do_setitimer(i, &itimer, NULL);
		spin_lock_irq(&current->sighand->siglock);
2320 2321 2322 2323 2324
		if (!(current->signal->flags & SIGNAL_GROUP_EXIT)) {
			__flush_signals(current);
			flush_signal_handlers(current, 1);
			sigemptyset(&current->blocked);
		}
L
Linus Torvalds 已提交
2325 2326 2327
		spin_unlock_irq(&current->sighand->siglock);
	}

2328 2329
	/* Wake up the parent if it is waiting so that it can recheck
	 * wait permission to the new task SID. */
2330
	read_lock(&tasklist_lock);
2331
	__wake_up_parent(current, current->real_parent);
2332
	read_unlock(&tasklist_lock);
L
Linus Torvalds 已提交
2333 2334 2335 2336 2337 2338 2339 2340 2341 2342 2343 2344 2345 2346 2347 2348 2349 2350 2351 2352 2353 2354 2355 2356
}

/* 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)
{
2357 2358 2359
	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) ||
2360 2361
		match_prefix(ROOTCONTEXT_STR, sizeof(ROOTCONTEXT_STR)-1, option, len) ||
		match_prefix(LABELSUPP_STR, sizeof(LABELSUPP_STR)-1, option, len));
L
Linus Torvalds 已提交
2362 2363 2364 2365 2366 2367 2368
}

static inline void take_option(char **to, char *from, int *first, int len)
{
	if (!*first) {
		**to = ',';
		*to += 1;
2369
	} else
L
Linus Torvalds 已提交
2370 2371 2372 2373 2374
		*first = 0;
	memcpy(*to, from, len);
	*to += len;
}

2375 2376
static inline void take_selinux_option(char **to, char *from, int *first,
				       int len)
2377 2378 2379 2380 2381 2382
{
	int current_size = 0;

	if (!*first) {
		**to = '|';
		*to += 1;
2383
	} else
2384 2385 2386 2387 2388 2389 2390 2391 2392 2393 2394 2395
		*first = 0;

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

2396
static int selinux_sb_copy_data(char *orig, char *copy)
L
Linus Torvalds 已提交
2397 2398 2399 2400
{
	int fnosec, fsec, rc = 0;
	char *in_save, *in_curr, *in_end;
	char *sec_curr, *nosec_save, *nosec;
2401
	int open_quote = 0;
L
Linus Torvalds 已提交
2402 2403 2404 2405 2406 2407 2408 2409 2410 2411 2412 2413 2414 2415 2416

	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 {
2417 2418 2419 2420
		if (*in_end == '"')
			open_quote = !open_quote;
		if ((*in_end == ',' && open_quote == 0) ||
				*in_end == '\0') {
L
Linus Torvalds 已提交
2421 2422 2423
			int len = in_end - in_curr;

			if (selinux_option(in_curr, len))
2424
				take_selinux_option(&sec_curr, in_curr, &fsec, len);
L
Linus Torvalds 已提交
2425 2426 2427 2428 2429 2430 2431
			else
				take_option(&nosec, in_curr, &fnosec, len);

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

2432
	strcpy(in_save, nosec_save);
2433
	free_page((unsigned long)nosec_save);
L
Linus Torvalds 已提交
2434 2435 2436 2437
out:
	return rc;
}

2438 2439 2440 2441 2442 2443 2444 2445 2446 2447 2448 2449 2450 2451 2452 2453 2454 2455 2456 2457 2458 2459 2460 2461 2462 2463 2464 2465 2466 2467 2468 2469 2470 2471 2472
static int selinux_sb_remount(struct super_block *sb, void *data)
{
	int rc, i, *flags;
	struct security_mnt_opts opts;
	char *secdata, **mount_options;
	struct superblock_security_struct *sbsec = sb->s_security;

	if (!(sbsec->flags & SE_SBINITIALIZED))
		return 0;

	if (!data)
		return 0;

	if (sb->s_type->fs_flags & FS_BINARY_MOUNTDATA)
		return 0;

	security_init_mnt_opts(&opts);
	secdata = alloc_secdata();
	if (!secdata)
		return -ENOMEM;
	rc = selinux_sb_copy_data(data, secdata);
	if (rc)
		goto out_free_secdata;

	rc = selinux_parse_opts_str(secdata, &opts);
	if (rc)
		goto out_free_secdata;

	mount_options = opts.mnt_opts;
	flags = opts.mnt_opts_flags;

	for (i = 0; i < opts.num_mnt_opts; i++) {
		u32 sid;
		size_t len;

2473
		if (flags[i] == SBLABEL_MNT)
2474 2475 2476 2477 2478
			continue;
		len = strlen(mount_options[i]);
		rc = security_context_to_sid(mount_options[i], len, &sid);
		if (rc) {
			printk(KERN_WARNING "SELinux: security_context_to_sid"
2479 2480
			       "(%s) failed for (dev %s, type %s) errno=%d\n",
			       mount_options[i], sb->s_id, sb->s_type->name, rc);
2481 2482 2483 2484 2485 2486 2487 2488 2489 2490 2491 2492 2493 2494 2495 2496 2497 2498 2499 2500 2501 2502 2503 2504 2505 2506 2507 2508 2509 2510 2511 2512 2513 2514 2515 2516 2517
			goto out_free_opts;
		}
		rc = -EINVAL;
		switch (flags[i]) {
		case FSCONTEXT_MNT:
			if (bad_option(sbsec, FSCONTEXT_MNT, sbsec->sid, sid))
				goto out_bad_option;
			break;
		case CONTEXT_MNT:
			if (bad_option(sbsec, CONTEXT_MNT, sbsec->mntpoint_sid, sid))
				goto out_bad_option;
			break;
		case ROOTCONTEXT_MNT: {
			struct inode_security_struct *root_isec;
			root_isec = sb->s_root->d_inode->i_security;

			if (bad_option(sbsec, ROOTCONTEXT_MNT, root_isec->sid, sid))
				goto out_bad_option;
			break;
		}
		case DEFCONTEXT_MNT:
			if (bad_option(sbsec, DEFCONTEXT_MNT, sbsec->def_sid, sid))
				goto out_bad_option;
			break;
		default:
			goto out_free_opts;
		}
	}

	rc = 0;
out_free_opts:
	security_free_mnt_opts(&opts);
out_free_secdata:
	free_secdata(secdata);
	return rc;
out_bad_option:
	printk(KERN_WARNING "SELinux: unable to change security options "
2518 2519
	       "during remount (dev %s, type=%s)\n", sb->s_id,
	       sb->s_type->name);
2520 2521 2522
	goto out_free_opts;
}

2523
static int selinux_sb_kern_mount(struct super_block *sb, int flags, void *data)
L
Linus Torvalds 已提交
2524
{
2525
	const struct cred *cred = current_cred();
2526
	struct common_audit_data ad;
L
Linus Torvalds 已提交
2527 2528 2529 2530 2531 2532
	int rc;

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

2533 2534 2535 2536
	/* Allow all mounts performed by the kernel */
	if (flags & MS_KERNMOUNT)
		return 0;

2537
	ad.type = LSM_AUDIT_DATA_DENTRY;
2538
	ad.u.dentry = sb->s_root;
2539
	return superblock_has_perm(cred, sb, FILESYSTEM__MOUNT, &ad);
L
Linus Torvalds 已提交
2540 2541
}

2542
static int selinux_sb_statfs(struct dentry *dentry)
L
Linus Torvalds 已提交
2543
{
2544
	const struct cred *cred = current_cred();
2545
	struct common_audit_data ad;
L
Linus Torvalds 已提交
2546

2547
	ad.type = LSM_AUDIT_DATA_DENTRY;
2548
	ad.u.dentry = dentry->d_sb->s_root;
2549
	return superblock_has_perm(cred, dentry->d_sb, FILESYSTEM__GETATTR, &ad);
L
Linus Torvalds 已提交
2550 2551
}

A
Al Viro 已提交
2552
static int selinux_mount(const char *dev_name,
2553
			 struct path *path,
A
Al Viro 已提交
2554
			 const char *type,
2555 2556
			 unsigned long flags,
			 void *data)
L
Linus Torvalds 已提交
2557
{
2558
	const struct cred *cred = current_cred();
L
Linus Torvalds 已提交
2559 2560

	if (flags & MS_REMOUNT)
2561
		return superblock_has_perm(cred, path->dentry->d_sb,
2562
					   FILESYSTEM__REMOUNT, NULL);
L
Linus Torvalds 已提交
2563
	else
E
Eric Paris 已提交
2564
		return path_has_perm(cred, path, FILE__MOUNTON);
L
Linus Torvalds 已提交
2565 2566 2567 2568
}

static int selinux_umount(struct vfsmount *mnt, int flags)
{
2569
	const struct cred *cred = current_cred();
L
Linus Torvalds 已提交
2570

2571
	return superblock_has_perm(cred, mnt->mnt_sb,
2572
				   FILESYSTEM__UNMOUNT, NULL);
L
Linus Torvalds 已提交
2573 2574 2575 2576 2577 2578 2579 2580 2581 2582 2583 2584 2585 2586
}

/* 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);
}

2587 2588 2589 2590 2591 2592 2593 2594 2595 2596 2597 2598 2599 2600 2601 2602 2603 2604 2605 2606 2607 2608 2609 2610 2611 2612 2613 2614 2615 2616 2617 2618 2619 2620
static int selinux_dentry_init_security(struct dentry *dentry, int mode,
					struct qstr *name, void **ctx,
					u32 *ctxlen)
{
	const struct cred *cred = current_cred();
	struct task_security_struct *tsec;
	struct inode_security_struct *dsec;
	struct superblock_security_struct *sbsec;
	struct inode *dir = dentry->d_parent->d_inode;
	u32 newsid;
	int rc;

	tsec = cred->security;
	dsec = dir->i_security;
	sbsec = dir->i_sb->s_security;

	if (tsec->create_sid && sbsec->behavior != SECURITY_FS_USE_MNTPOINT) {
		newsid = tsec->create_sid;
	} else {
		rc = security_transition_sid(tsec->sid, dsec->sid,
					     inode_mode_to_security_class(mode),
					     name,
					     &newsid);
		if (rc) {
			printk(KERN_WARNING
				"%s: security_transition_sid failed, rc=%d\n",
			       __func__, -rc);
			return rc;
		}
	}

	return security_sid_to_context(newsid, (char **)ctx, ctxlen);
}

2621
static int selinux_inode_init_security(struct inode *inode, struct inode *dir,
2622 2623
				       const struct qstr *qstr,
				       const char **name,
2624
				       void **value, size_t *len)
2625
{
2626
	const struct task_security_struct *tsec = current_security();
2627 2628
	struct inode_security_struct *dsec;
	struct superblock_security_struct *sbsec;
2629
	u32 sid, newsid, clen;
2630
	int rc;
2631
	char *context;
2632 2633 2634 2635

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

2636 2637 2638
	sid = tsec->sid;
	newsid = tsec->create_sid;

2639 2640 2641
	if ((sbsec->flags & SE_SBINITIALIZED) &&
	    (sbsec->behavior == SECURITY_FS_USE_MNTPOINT))
		newsid = sbsec->mntpoint_sid;
2642
	else if (!newsid || !(sbsec->flags & SBLABEL_MNT)) {
2643
		rc = security_transition_sid(sid, dsec->sid,
2644
					     inode_mode_to_security_class(inode->i_mode),
2645
					     qstr, &newsid);
2646 2647 2648 2649
		if (rc) {
			printk(KERN_WARNING "%s:  "
			       "security_transition_sid failed, rc=%d (dev=%s "
			       "ino=%ld)\n",
2650
			       __func__,
2651 2652 2653 2654 2655
			       -rc, inode->i_sb->s_id, inode->i_ino);
			return rc;
		}
	}

2656
	/* Possibly defer initialization to selinux_complete_init. */
2657
	if (sbsec->flags & SE_SBINITIALIZED) {
2658 2659 2660 2661 2662
		struct inode_security_struct *isec = inode->i_security;
		isec->sclass = inode_mode_to_security_class(inode->i_mode);
		isec->sid = newsid;
		isec->initialized = 1;
	}
2663

2664
	if (!ss_initialized || !(sbsec->flags & SBLABEL_MNT))
2665 2666
		return -EOPNOTSUPP;

2667 2668
	if (name)
		*name = XATTR_SELINUX_SUFFIX;
2669

2670
	if (value && len) {
2671
		rc = security_sid_to_context_force(newsid, &context, &clen);
2672
		if (rc)
2673 2674 2675
			return rc;
		*value = context;
		*len = clen;
2676 2677 2678 2679 2680
	}

	return 0;
}

A
Al Viro 已提交
2681
static int selinux_inode_create(struct inode *dir, struct dentry *dentry, umode_t mode)
L
Linus Torvalds 已提交
2682 2683 2684 2685 2686 2687 2688 2689 2690 2691 2692 2693 2694 2695 2696 2697 2698 2699 2700
{
	return may_create(dir, dentry, SECCLASS_FILE);
}

static int selinux_inode_link(struct dentry *old_dentry, struct inode *dir, struct dentry *new_dentry)
{
	return may_link(dir, old_dentry, MAY_LINK);
}

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

2701
static int selinux_inode_mkdir(struct inode *dir, struct dentry *dentry, umode_t mask)
L
Linus Torvalds 已提交
2702 2703 2704 2705 2706 2707 2708 2709 2710
{
	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);
}

A
Al Viro 已提交
2711
static int selinux_inode_mknod(struct inode *dir, struct dentry *dentry, umode_t mode, dev_t dev)
L
Linus Torvalds 已提交
2712 2713 2714 2715 2716
{
	return may_create(dir, dentry, inode_mode_to_security_class(mode));
}

static int selinux_inode_rename(struct inode *old_inode, struct dentry *old_dentry,
2717
				struct inode *new_inode, struct dentry *new_dentry)
L
Linus Torvalds 已提交
2718 2719 2720 2721 2722 2723
{
	return may_rename(old_inode, old_dentry, new_inode, new_dentry);
}

static int selinux_inode_readlink(struct dentry *dentry)
{
2724 2725
	const struct cred *cred = current_cred();

E
Eric Paris 已提交
2726
	return dentry_has_perm(cred, dentry, FILE__READ);
L
Linus Torvalds 已提交
2727 2728 2729 2730
}

static int selinux_inode_follow_link(struct dentry *dentry, struct nameidata *nameidata)
{
2731
	const struct cred *cred = current_cred();
L
Linus Torvalds 已提交
2732

E
Eric Paris 已提交
2733
	return dentry_has_perm(cred, dentry, FILE__READ);
L
Linus Torvalds 已提交
2734 2735
}

2736 2737 2738
static noinline int audit_inode_permission(struct inode *inode,
					   u32 perms, u32 audited, u32 denied,
					   unsigned flags)
L
Linus Torvalds 已提交
2739
{
2740
	struct common_audit_data ad;
2741 2742 2743
	struct inode_security_struct *isec = inode->i_security;
	int rc;

2744
	ad.type = LSM_AUDIT_DATA_INODE;
2745 2746 2747 2748 2749 2750 2751 2752 2753
	ad.u.inode = inode;

	rc = slow_avc_audit(current_sid(), isec->sid, isec->sclass, perms,
			    audited, denied, &ad, flags);
	if (rc)
		return rc;
	return 0;
}

2754
static int selinux_inode_permission(struct inode *inode, int mask)
L
Linus Torvalds 已提交
2755
{
2756
	const struct cred *cred = current_cred();
2757 2758
	u32 perms;
	bool from_access;
2759
	unsigned flags = mask & MAY_NOT_BLOCK;
2760 2761 2762 2763 2764
	struct inode_security_struct *isec;
	u32 sid;
	struct av_decision avd;
	int rc, rc2;
	u32 audited, denied;
L
Linus Torvalds 已提交
2765

2766
	from_access = mask & MAY_ACCESS;
2767 2768
	mask &= (MAY_READ|MAY_WRITE|MAY_EXEC|MAY_APPEND);

2769 2770
	/* No permission to check.  Existence test. */
	if (!mask)
L
Linus Torvalds 已提交
2771 2772
		return 0;

2773
	validate_creds(cred);
2774

2775 2776
	if (unlikely(IS_PRIVATE(inode)))
		return 0;
2777 2778 2779

	perms = file_mask_to_av(inode->i_mode, mask);

2780 2781 2782 2783 2784 2785 2786 2787 2788 2789
	sid = cred_sid(cred);
	isec = inode->i_security;

	rc = avc_has_perm_noaudit(sid, isec->sid, isec->sclass, perms, 0, &avd);
	audited = avc_audit_required(perms, &avd, rc,
				     from_access ? FILE__AUDIT_ACCESS : 0,
				     &denied);
	if (likely(!audited))
		return rc;

2790
	rc2 = audit_inode_permission(inode, perms, audited, denied, flags);
2791 2792 2793
	if (rc2)
		return rc2;
	return rc;
L
Linus Torvalds 已提交
2794 2795 2796 2797
}

static int selinux_inode_setattr(struct dentry *dentry, struct iattr *iattr)
{
2798
	const struct cred *cred = current_cred();
2799
	unsigned int ia_valid = iattr->ia_valid;
2800
	__u32 av = FILE__WRITE;
L
Linus Torvalds 已提交
2801

2802 2803 2804 2805 2806 2807 2808
	/* ATTR_FORCE is just used for ATTR_KILL_S[UG]ID. */
	if (ia_valid & ATTR_FORCE) {
		ia_valid &= ~(ATTR_KILL_SUID | ATTR_KILL_SGID | ATTR_MODE |
			      ATTR_FORCE);
		if (!ia_valid)
			return 0;
	}
L
Linus Torvalds 已提交
2809

2810 2811
	if (ia_valid & (ATTR_MODE | ATTR_UID | ATTR_GID |
			ATTR_ATIME_SET | ATTR_MTIME_SET | ATTR_TIMES_SET))
E
Eric Paris 已提交
2812
		return dentry_has_perm(cred, dentry, FILE__SETATTR);
L
Linus Torvalds 已提交
2813

2814
	if (selinux_policycap_openperm && (ia_valid & ATTR_SIZE))
2815 2816 2817
		av |= FILE__OPEN;

	return dentry_has_perm(cred, dentry, av);
L
Linus Torvalds 已提交
2818 2819 2820 2821
}

static int selinux_inode_getattr(struct vfsmount *mnt, struct dentry *dentry)
{
2822
	const struct cred *cred = current_cred();
E
Eric Paris 已提交
2823 2824 2825 2826
	struct path path;

	path.dentry = dentry;
	path.mnt = mnt;
2827

E
Eric Paris 已提交
2828
	return path_has_perm(cred, &path, FILE__GETATTR);
L
Linus Torvalds 已提交
2829 2830
}

2831
static int selinux_inode_setotherxattr(struct dentry *dentry, const char *name)
2832
{
2833 2834
	const struct cred *cred = current_cred();

2835 2836 2837 2838 2839 2840 2841 2842 2843 2844 2845 2846 2847 2848
	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. */
E
Eric Paris 已提交
2849
	return dentry_has_perm(cred, dentry, FILE__SETATTR);
2850 2851
}

2852 2853
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
2854 2855 2856 2857
{
	struct inode *inode = dentry->d_inode;
	struct inode_security_struct *isec = inode->i_security;
	struct superblock_security_struct *sbsec;
2858
	struct common_audit_data ad;
2859
	u32 newsid, sid = current_sid();
L
Linus Torvalds 已提交
2860 2861
	int rc = 0;

2862 2863
	if (strcmp(name, XATTR_NAME_SELINUX))
		return selinux_inode_setotherxattr(dentry, name);
L
Linus Torvalds 已提交
2864 2865

	sbsec = inode->i_sb->s_security;
2866
	if (!(sbsec->flags & SBLABEL_MNT))
L
Linus Torvalds 已提交
2867 2868
		return -EOPNOTSUPP;

2869
	if (!inode_owner_or_capable(inode))
L
Linus Torvalds 已提交
2870 2871
		return -EPERM;

2872
	ad.type = LSM_AUDIT_DATA_DENTRY;
2873
	ad.u.dentry = dentry;
L
Linus Torvalds 已提交
2874

2875
	rc = avc_has_perm(sid, isec->sid, isec->sclass,
L
Linus Torvalds 已提交
2876 2877 2878 2879 2880
			  FILE__RELABELFROM, &ad);
	if (rc)
		return rc;

	rc = security_context_to_sid(value, size, &newsid);
2881
	if (rc == -EINVAL) {
2882 2883 2884 2885 2886 2887 2888
		if (!capable(CAP_MAC_ADMIN)) {
			struct audit_buffer *ab;
			size_t audit_size;
			const char *str;

			/* We strip a nul only if it is at the end, otherwise the
			 * context contains a nul and we should audit that */
2889 2890 2891 2892 2893 2894 2895 2896 2897 2898
			if (value) {
				str = value;
				if (str[size - 1] == '\0')
					audit_size = size - 1;
				else
					audit_size = size;
			} else {
				str = "";
				audit_size = 0;
			}
2899 2900 2901 2902 2903
			ab = audit_log_start(current->audit_context, GFP_ATOMIC, AUDIT_SELINUX_ERR);
			audit_log_format(ab, "op=setxattr invalid_context=");
			audit_log_n_untrustedstring(ab, value, audit_size);
			audit_log_end(ab);

2904
			return rc;
2905
		}
2906 2907
		rc = security_context_to_sid_force(value, size, &newsid);
	}
L
Linus Torvalds 已提交
2908 2909 2910
	if (rc)
		return rc;

2911
	rc = avc_has_perm(sid, newsid, isec->sclass,
L
Linus Torvalds 已提交
2912 2913 2914 2915
			  FILE__RELABELTO, &ad);
	if (rc)
		return rc;

2916
	rc = security_validate_transition(isec->sid, newsid, sid,
2917
					  isec->sclass);
L
Linus Torvalds 已提交
2918 2919 2920 2921 2922 2923 2924 2925 2926 2927
	if (rc)
		return rc;

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

2928
static void selinux_inode_post_setxattr(struct dentry *dentry, const char *name,
2929
					const void *value, size_t size,
2930
					int flags)
L
Linus Torvalds 已提交
2931 2932 2933 2934 2935 2936 2937 2938 2939 2940 2941
{
	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;
	}

2942
	rc = security_context_to_sid_force(value, size, &newsid);
L
Linus Torvalds 已提交
2943
	if (rc) {
2944 2945 2946
		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
2947 2948 2949
		return;
	}

2950
	isec->sclass = inode_mode_to_security_class(inode->i_mode);
L
Linus Torvalds 已提交
2951
	isec->sid = newsid;
2952 2953
	isec->initialized = 1;

L
Linus Torvalds 已提交
2954 2955 2956
	return;
}

2957
static int selinux_inode_getxattr(struct dentry *dentry, const char *name)
L
Linus Torvalds 已提交
2958
{
2959 2960
	const struct cred *cred = current_cred();

E
Eric Paris 已提交
2961
	return dentry_has_perm(cred, dentry, FILE__GETATTR);
L
Linus Torvalds 已提交
2962 2963
}

2964
static int selinux_inode_listxattr(struct dentry *dentry)
L
Linus Torvalds 已提交
2965
{
2966 2967
	const struct cred *cred = current_cred();

E
Eric Paris 已提交
2968
	return dentry_has_perm(cred, dentry, FILE__GETATTR);
L
Linus Torvalds 已提交
2969 2970
}

2971
static int selinux_inode_removexattr(struct dentry *dentry, const char *name)
L
Linus Torvalds 已提交
2972
{
2973 2974
	if (strcmp(name, XATTR_NAME_SELINUX))
		return selinux_inode_setotherxattr(dentry, name);
L
Linus Torvalds 已提交
2975 2976 2977 2978 2979 2980

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

2981
/*
2982
 * Copy the inode security context value to the user.
2983 2984 2985
 *
 * Permission check is handled by selinux_inode_getxattr hook.
 */
2986
static int selinux_inode_getsecurity(const struct inode *inode, const char *name, void **buffer, bool alloc)
L
Linus Torvalds 已提交
2987
{
2988 2989 2990
	u32 size;
	int error;
	char *context = NULL;
L
Linus Torvalds 已提交
2991
	struct inode_security_struct *isec = inode->i_security;
2992

2993 2994
	if (strcmp(name, XATTR_SELINUX_SUFFIX))
		return -EOPNOTSUPP;
2995

2996 2997 2998 2999 3000 3001 3002 3003 3004
	/*
	 * 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.
	 */
3005
	error = selinux_capable(current_cred(), &init_user_ns, CAP_MAC_ADMIN,
3006
				SECURITY_CAP_NOAUDIT);
3007 3008 3009 3010 3011
	if (!error)
		error = security_sid_to_context_force(isec->sid, &context,
						      &size);
	else
		error = security_sid_to_context(isec->sid, &context, &size);
3012 3013 3014 3015 3016 3017 3018 3019 3020 3021
	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
3022 3023 3024
}

static int selinux_inode_setsecurity(struct inode *inode, const char *name,
3025
				     const void *value, size_t size, int flags)
L
Linus Torvalds 已提交
3026 3027 3028 3029 3030 3031 3032 3033 3034 3035 3036
{
	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;

3037
	rc = security_context_to_sid((void *)value, size, &newsid);
L
Linus Torvalds 已提交
3038 3039 3040
	if (rc)
		return rc;

3041
	isec->sclass = inode_mode_to_security_class(inode->i_mode);
L
Linus Torvalds 已提交
3042
	isec->sid = newsid;
3043
	isec->initialized = 1;
L
Linus Torvalds 已提交
3044 3045 3046 3047 3048 3049 3050 3051 3052 3053 3054
	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;
}

3055 3056 3057 3058 3059 3060
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
3061 3062
/* file security operations */

3063
static int selinux_revalidate_file_permission(struct file *file, int mask)
L
Linus Torvalds 已提交
3064
{
3065
	const struct cred *cred = current_cred();
A
Al Viro 已提交
3066
	struct inode *inode = file_inode(file);
L
Linus Torvalds 已提交
3067 3068 3069 3070 3071

	/* 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;

3072 3073
	return file_has_perm(cred, file,
			     file_mask_to_av(inode->i_mode, mask));
L
Linus Torvalds 已提交
3074 3075
}

3076 3077
static int selinux_file_permission(struct file *file, int mask)
{
A
Al Viro 已提交
3078
	struct inode *inode = file_inode(file);
3079 3080 3081 3082
	struct file_security_struct *fsec = file->f_security;
	struct inode_security_struct *isec = inode->i_security;
	u32 sid = current_sid();

3083
	if (!mask)
3084 3085 3086
		/* No permission to check.  Existence test. */
		return 0;

3087 3088
	if (sid == fsec->sid && fsec->isid == isec->sid &&
	    fsec->pseqno == avc_policy_seqno())
3089
		/* No change since file_open check. */
3090 3091
		return 0;

3092 3093 3094
	return selinux_revalidate_file_permission(file, mask);
}

L
Linus Torvalds 已提交
3095 3096 3097 3098 3099 3100 3101 3102 3103 3104 3105 3106 3107
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)
{
3108
	const struct cred *cred = current_cred();
3109
	int error = 0;
L
Linus Torvalds 已提交
3110

3111 3112 3113 3114 3115 3116 3117
	switch (cmd) {
	case FIONREAD:
	/* fall through */
	case FIBMAP:
	/* fall through */
	case FIGETBSZ:
	/* fall through */
3118
	case FS_IOC_GETFLAGS:
3119
	/* fall through */
3120
	case FS_IOC_GETVERSION:
3121 3122
		error = file_has_perm(cred, file, FILE__GETATTR);
		break;
L
Linus Torvalds 已提交
3123

3124
	case FS_IOC_SETFLAGS:
3125
	/* fall through */
3126
	case FS_IOC_SETVERSION:
3127 3128 3129 3130 3131 3132 3133 3134 3135
		error = file_has_perm(cred, file, FILE__SETATTR);
		break;

	/* sys_ioctl() checks */
	case FIONBIO:
	/* fall through */
	case FIOASYNC:
		error = file_has_perm(cred, file, 0);
		break;
L
Linus Torvalds 已提交
3136

3137 3138
	case KDSKBENT:
	case KDSKBSENT:
3139 3140
		error = cred_has_capability(cred, CAP_SYS_TTY_CONFIG,
					    SECURITY_CAP_AUDIT);
3141 3142 3143 3144 3145 3146 3147 3148 3149
		break;

	/* default case assumes that the command will go
	 * to the file's ioctl() function.
	 */
	default:
		error = file_has_perm(cred, file, FILE__IOCTL);
	}
	return error;
L
Linus Torvalds 已提交
3150 3151
}

3152 3153
static int default_noexec;

L
Linus Torvalds 已提交
3154 3155
static int file_map_prot_check(struct file *file, unsigned long prot, int shared)
{
3156
	const struct cred *cred = current_cred();
D
David Howells 已提交
3157
	int rc = 0;
3158

3159 3160
	if (default_noexec &&
	    (prot & PROT_EXEC) && (!file || (!shared && (prot & PROT_WRITE)))) {
L
Linus Torvalds 已提交
3161 3162 3163 3164 3165
		/*
		 * 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
3166
		rc = cred_has_perm(cred, cred, PROCESS__EXECMEM);
L
Linus Torvalds 已提交
3167
		if (rc)
D
David Howells 已提交
3168
			goto error;
L
Linus Torvalds 已提交
3169 3170 3171 3172 3173 3174 3175 3176 3177 3178 3179 3180 3181
	}

	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;

3182
		return file_has_perm(cred, file, av);
L
Linus Torvalds 已提交
3183
	}
D
David Howells 已提交
3184 3185 3186

error:
	return rc;
L
Linus Torvalds 已提交
3187 3188
}

3189
static int selinux_mmap_addr(unsigned long addr)
L
Linus Torvalds 已提交
3190
{
3191
	int rc = 0;
3192
	u32 sid = current_sid();
L
Linus Torvalds 已提交
3193

3194 3195 3196 3197 3198 3199
	/*
	 * notice that we are intentionally putting the SELinux check before
	 * the secondary cap_file_mmap check.  This is such a likely attempt
	 * at bad behaviour/exploit that we always want to get the AVC, even
	 * if DAC would have also denied the operation.
	 */
3200
	if (addr < CONFIG_LSM_MMAP_MIN_ADDR) {
3201 3202
		rc = avc_has_perm(sid, sid, SECCLASS_MEMPROTECT,
				  MEMPROTECT__MMAP_ZERO, NULL);
3203 3204 3205 3206 3207
		if (rc)
			return rc;
	}

	/* do DAC check on address space usage */
3208 3209
	return cap_mmap_addr(addr);
}
L
Linus Torvalds 已提交
3210

3211 3212 3213
static int selinux_mmap_file(struct file *file, unsigned long reqprot,
			     unsigned long prot, unsigned long flags)
{
L
Linus Torvalds 已提交
3214 3215 3216 3217 3218 3219 3220 3221 3222 3223 3224
	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)
{
3225
	const struct cred *cred = current_cred();
L
Linus Torvalds 已提交
3226 3227 3228 3229

	if (selinux_checkreqprot)
		prot = reqprot;

3230 3231
	if (default_noexec &&
	    (prot & PROT_EXEC) && !(vma->vm_flags & VM_EXEC)) {
3232
		int rc = 0;
3233 3234
		if (vma->vm_start >= vma->vm_mm->start_brk &&
		    vma->vm_end <= vma->vm_mm->brk) {
D
David Howells 已提交
3235
			rc = cred_has_perm(cred, cred, PROCESS__EXECHEAP);
3236 3237 3238
		} else if (!vma->vm_file &&
			   vma->vm_start <= vma->vm_mm->start_stack &&
			   vma->vm_end >= vma->vm_mm->start_stack) {
3239
			rc = current_has_perm(current, PROCESS__EXECSTACK);
3240 3241 3242 3243 3244 3245 3246 3247
		} 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
3248
			rc = file_has_perm(cred, vma->vm_file, FILE__EXECMOD);
3249
		}
3250 3251 3252
		if (rc)
			return rc;
	}
L
Linus Torvalds 已提交
3253 3254 3255 3256 3257 3258

	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)
{
3259 3260 3261
	const struct cred *cred = current_cred();

	return file_has_perm(cred, file, FILE__LOCK);
L
Linus Torvalds 已提交
3262 3263 3264 3265 3266
}

static int selinux_file_fcntl(struct file *file, unsigned int cmd,
			      unsigned long arg)
{
3267
	const struct cred *cred = current_cred();
L
Linus Torvalds 已提交
3268 3269 3270
	int err = 0;

	switch (cmd) {
3271 3272
	case F_SETFL:
		if ((file->f_flags & O_APPEND) && !(arg & O_APPEND)) {
3273
			err = file_has_perm(cred, file, FILE__WRITE);
L
Linus Torvalds 已提交
3274
			break;
3275 3276 3277 3278 3279 3280 3281
		}
		/* fall through */
	case F_SETOWN:
	case F_SETSIG:
	case F_GETFL:
	case F_GETOWN:
	case F_GETSIG:
3282
	case F_GETOWNER_UIDS:
3283
		/* Just check FD__USE permission */
3284
		err = file_has_perm(cred, file, 0);
3285 3286 3287 3288
		break;
	case F_GETLK:
	case F_SETLK:
	case F_SETLKW:
L
Linus Torvalds 已提交
3289
#if BITS_PER_LONG == 32
3290 3291 3292
	case F_GETLK64:
	case F_SETLK64:
	case F_SETLKW64:
L
Linus Torvalds 已提交
3293
#endif
3294
		err = file_has_perm(cred, file, FILE__LOCK);
3295
		break;
L
Linus Torvalds 已提交
3296 3297 3298 3299 3300 3301 3302 3303 3304 3305
	}

	return err;
}

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

	fsec = file->f_security;
3306
	fsec->fown_sid = current_sid();
L
Linus Torvalds 已提交
3307 3308 3309 3310 3311 3312 3313

	return 0;
}

static int selinux_file_send_sigiotask(struct task_struct *tsk,
				       struct fown_struct *fown, int signum)
{
3314
	struct file *file;
3315
	u32 sid = task_sid(tsk);
L
Linus Torvalds 已提交
3316 3317 3318 3319
	u32 perm;
	struct file_security_struct *fsec;

	/* struct fown_struct is never outside the context of a struct file */
3320
	file = container_of(fown, struct file, f_owner);
L
Linus Torvalds 已提交
3321 3322 3323 3324 3325 3326 3327 3328

	fsec = file->f_security;

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

3329
	return avc_has_perm(fsec->fown_sid, sid,
L
Linus Torvalds 已提交
3330 3331 3332 3333 3334
			    SECCLASS_PROCESS, perm, NULL);
}

static int selinux_file_receive(struct file *file)
{
3335 3336 3337
	const struct cred *cred = current_cred();

	return file_has_perm(cred, file, file_to_av(file));
L
Linus Torvalds 已提交
3338 3339
}

3340
static int selinux_file_open(struct file *file, const struct cred *cred)
3341 3342 3343
{
	struct file_security_struct *fsec;
	struct inode_security_struct *isec;
D
David Howells 已提交
3344

3345
	fsec = file->f_security;
A
Al Viro 已提交
3346
	isec = file_inode(file)->i_security;
3347 3348 3349 3350 3351 3352 3353 3354 3355 3356 3357 3358 3359 3360 3361 3362 3363
	/*
	 * 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.
	 */
3364
	return file_path_has_perm(cred, file, open_file_to_av(file));
3365 3366
}

L
Linus Torvalds 已提交
3367 3368 3369 3370
/* task security operations */

static int selinux_task_create(unsigned long clone_flags)
{
3371
	return current_has_perm(current, PROCESS__FORK);
L
Linus Torvalds 已提交
3372 3373
}

3374 3375 3376 3377 3378 3379 3380 3381 3382 3383 3384 3385 3386 3387 3388
/*
 * allocate the SELinux part of blank credentials
 */
static int selinux_cred_alloc_blank(struct cred *cred, gfp_t gfp)
{
	struct task_security_struct *tsec;

	tsec = kzalloc(sizeof(struct task_security_struct), gfp);
	if (!tsec)
		return -ENOMEM;

	cred->security = tsec;
	return 0;
}

D
David Howells 已提交
3389 3390 3391 3392
/*
 * 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
3393
{
D
David Howells 已提交
3394
	struct task_security_struct *tsec = cred->security;
3395

3396 3397 3398 3399 3400
	/*
	 * cred->security == NULL if security_cred_alloc_blank() or
	 * security_prepare_creds() returned an error.
	 */
	BUG_ON(cred->security && (unsigned long) cred->security < PAGE_SIZE);
3401
	cred->security = (void *) 0x7UL;
D
David Howells 已提交
3402 3403
	kfree(tsec);
}
L
Linus Torvalds 已提交
3404

D
David Howells 已提交
3405 3406 3407 3408 3409 3410 3411 3412
/*
 * 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
3413

D
David Howells 已提交
3414
	old_tsec = old->security;
L
Linus Torvalds 已提交
3415

D
David Howells 已提交
3416 3417 3418
	tsec = kmemdup(old_tsec, sizeof(struct task_security_struct), gfp);
	if (!tsec)
		return -ENOMEM;
L
Linus Torvalds 已提交
3419

D
David Howells 已提交
3420
	new->security = tsec;
L
Linus Torvalds 已提交
3421 3422 3423
	return 0;
}

3424 3425 3426 3427 3428 3429 3430 3431 3432 3433 3434
/*
 * transfer the SELinux data to a blank set of creds
 */
static void selinux_cred_transfer(struct cred *new, const struct cred *old)
{
	const struct task_security_struct *old_tsec = old->security;
	struct task_security_struct *tsec = new->security;

	*tsec = *old_tsec;
}

3435 3436 3437 3438 3439 3440 3441 3442 3443 3444 3445 3446 3447 3448 3449 3450 3451 3452 3453 3454 3455 3456 3457 3458 3459 3460 3461 3462 3463 3464 3465 3466 3467 3468 3469 3470 3471 3472 3473 3474 3475
/*
 * 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;
3476
	return ret;
3477 3478
}

3479
static int selinux_kernel_module_request(char *kmod_name)
3480
{
3481 3482 3483 3484 3485
	u32 sid;
	struct common_audit_data ad;

	sid = task_sid(current);

3486
	ad.type = LSM_AUDIT_DATA_KMOD;
3487 3488 3489 3490
	ad.u.kmod_name = kmod_name;

	return avc_has_perm(sid, SECINITSID_KERNEL, SECCLASS_SYSTEM,
			    SYSTEM__MODULE_REQUEST, &ad);
3491 3492
}

L
Linus Torvalds 已提交
3493 3494
static int selinux_task_setpgid(struct task_struct *p, pid_t pgid)
{
3495
	return current_has_perm(p, PROCESS__SETPGID);
L
Linus Torvalds 已提交
3496 3497 3498 3499
}

static int selinux_task_getpgid(struct task_struct *p)
{
3500
	return current_has_perm(p, PROCESS__GETPGID);
L
Linus Torvalds 已提交
3501 3502 3503 3504
}

static int selinux_task_getsid(struct task_struct *p)
{
3505
	return current_has_perm(p, PROCESS__GETSESSION);
L
Linus Torvalds 已提交
3506 3507
}

3508 3509
static void selinux_task_getsecid(struct task_struct *p, u32 *secid)
{
3510
	*secid = task_sid(p);
3511 3512
}

L
Linus Torvalds 已提交
3513 3514 3515 3516
static int selinux_task_setnice(struct task_struct *p, int nice)
{
	int rc;

3517
	rc = cap_task_setnice(p, nice);
L
Linus Torvalds 已提交
3518 3519 3520
	if (rc)
		return rc;

3521
	return current_has_perm(p, PROCESS__SETSCHED);
L
Linus Torvalds 已提交
3522 3523
}

3524 3525
static int selinux_task_setioprio(struct task_struct *p, int ioprio)
{
3526 3527
	int rc;

3528
	rc = cap_task_setioprio(p, ioprio);
3529 3530 3531
	if (rc)
		return rc;

3532
	return current_has_perm(p, PROCESS__SETSCHED);
3533 3534
}

3535 3536
static int selinux_task_getioprio(struct task_struct *p)
{
3537
	return current_has_perm(p, PROCESS__GETSCHED);
3538 3539
}

3540 3541
static int selinux_task_setrlimit(struct task_struct *p, unsigned int resource,
		struct rlimit *new_rlim)
L
Linus Torvalds 已提交
3542
{
3543
	struct rlimit *old_rlim = p->signal->rlim + resource;
L
Linus Torvalds 已提交
3544 3545 3546 3547

	/* 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
3548
	   upon context transitions.  See selinux_bprm_committing_creds. */
L
Linus Torvalds 已提交
3549
	if (old_rlim->rlim_max != new_rlim->rlim_max)
3550
		return current_has_perm(p, PROCESS__SETRLIMIT);
L
Linus Torvalds 已提交
3551 3552 3553 3554

	return 0;
}

3555
static int selinux_task_setscheduler(struct task_struct *p)
L
Linus Torvalds 已提交
3556
{
3557 3558
	int rc;

3559
	rc = cap_task_setscheduler(p);
3560 3561 3562
	if (rc)
		return rc;

3563
	return current_has_perm(p, PROCESS__SETSCHED);
L
Linus Torvalds 已提交
3564 3565 3566 3567
}

static int selinux_task_getscheduler(struct task_struct *p)
{
3568
	return current_has_perm(p, PROCESS__GETSCHED);
L
Linus Torvalds 已提交
3569 3570
}

3571 3572
static int selinux_task_movememory(struct task_struct *p)
{
3573
	return current_has_perm(p, PROCESS__SETSCHED);
3574 3575
}

3576 3577
static int selinux_task_kill(struct task_struct *p, struct siginfo *info,
				int sig, u32 secid)
L
Linus Torvalds 已提交
3578 3579 3580 3581 3582 3583 3584 3585
{
	u32 perm;
	int rc;

	if (!sig)
		perm = PROCESS__SIGNULL; /* null signal; existence test */
	else
		perm = signal_to_av(sig);
3586
	if (secid)
3587 3588
		rc = avc_has_perm(secid, task_sid(p),
				  SECCLASS_PROCESS, perm, NULL);
3589
	else
3590
		rc = current_has_perm(p, perm);
3591
	return rc;
L
Linus Torvalds 已提交
3592 3593 3594 3595
}

static int selinux_task_wait(struct task_struct *p)
{
3596
	return task_has_perm(p, current, PROCESS__SIGCHLD);
L
Linus Torvalds 已提交
3597 3598 3599 3600 3601 3602
}

static void selinux_task_to_inode(struct task_struct *p,
				  struct inode *inode)
{
	struct inode_security_struct *isec = inode->i_security;
3603
	u32 sid = task_sid(p);
L
Linus Torvalds 已提交
3604

3605
	isec->sid = sid;
L
Linus Torvalds 已提交
3606 3607 3608 3609
	isec->initialized = 1;
}

/* Returns error only if unable to parse addresses */
3610
static int selinux_parse_skb_ipv4(struct sk_buff *skb,
3611
			struct common_audit_data *ad, u8 *proto)
L
Linus Torvalds 已提交
3612 3613 3614 3615
{
	int offset, ihlen, ret = -EINVAL;
	struct iphdr _iph, *ih;

3616
	offset = skb_network_offset(skb);
L
Linus Torvalds 已提交
3617 3618 3619 3620 3621 3622 3623 3624
	ih = skb_header_pointer(skb, offset, sizeof(_iph), &_iph);
	if (ih == NULL)
		goto out;

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

3625 3626
	ad->u.net->v4info.saddr = ih->saddr;
	ad->u.net->v4info.daddr = ih->daddr;
L
Linus Torvalds 已提交
3627 3628
	ret = 0;

3629 3630 3631
	if (proto)
		*proto = ih->protocol;

L
Linus Torvalds 已提交
3632
	switch (ih->protocol) {
3633 3634
	case IPPROTO_TCP: {
		struct tcphdr _tcph, *th;
L
Linus Torvalds 已提交
3635

3636 3637
		if (ntohs(ih->frag_off) & IP_OFFSET)
			break;
L
Linus Torvalds 已提交
3638 3639 3640 3641 3642 3643

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

3644 3645
		ad->u.net->sport = th->source;
		ad->u.net->dport = th->dest;
L
Linus Torvalds 已提交
3646
		break;
3647 3648 3649 3650 3651 3652 3653 3654
	}

	case IPPROTO_UDP: {
		struct udphdr _udph, *uh;

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

L
Linus Torvalds 已提交
3655
		offset += ihlen;
3656
		uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph);
L
Linus Torvalds 已提交
3657
		if (uh == NULL)
3658
			break;
L
Linus Torvalds 已提交
3659

3660 3661
		ad->u.net->sport = uh->source;
		ad->u.net->dport = uh->dest;
3662 3663
		break;
	}
L
Linus Torvalds 已提交
3664

J
James Morris 已提交
3665 3666 3667 3668 3669 3670 3671 3672 3673 3674 3675
	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;

3676 3677
		ad->u.net->sport = dh->dccph_sport;
		ad->u.net->dport = dh->dccph_dport;
J
James Morris 已提交
3678
		break;
3679
	}
J
James Morris 已提交
3680

3681 3682 3683
	default:
		break;
	}
L
Linus Torvalds 已提交
3684 3685 3686 3687 3688 3689 3690
out:
	return ret;
}

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

/* Returns error only if unable to parse addresses */
3691
static int selinux_parse_skb_ipv6(struct sk_buff *skb,
3692
			struct common_audit_data *ad, u8 *proto)
L
Linus Torvalds 已提交
3693 3694 3695 3696
{
	u8 nexthdr;
	int ret = -EINVAL, offset;
	struct ipv6hdr _ipv6h, *ip6;
3697
	__be16 frag_off;
L
Linus Torvalds 已提交
3698

3699
	offset = skb_network_offset(skb);
L
Linus Torvalds 已提交
3700 3701 3702 3703
	ip6 = skb_header_pointer(skb, offset, sizeof(_ipv6h), &_ipv6h);
	if (ip6 == NULL)
		goto out;

3704 3705
	ad->u.net->v6info.saddr = ip6->saddr;
	ad->u.net->v6info.daddr = ip6->daddr;
L
Linus Torvalds 已提交
3706 3707 3708 3709
	ret = 0;

	nexthdr = ip6->nexthdr;
	offset += sizeof(_ipv6h);
3710
	offset = ipv6_skip_exthdr(skb, offset, &nexthdr, &frag_off);
L
Linus Torvalds 已提交
3711 3712 3713
	if (offset < 0)
		goto out;

3714 3715 3716
	if (proto)
		*proto = nexthdr;

L
Linus Torvalds 已提交
3717 3718
	switch (nexthdr) {
	case IPPROTO_TCP: {
3719
		struct tcphdr _tcph, *th;
L
Linus Torvalds 已提交
3720 3721 3722 3723 3724

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

3725 3726
		ad->u.net->sport = th->source;
		ad->u.net->dport = th->dest;
L
Linus Torvalds 已提交
3727 3728 3729 3730 3731 3732 3733 3734 3735 3736
		break;
	}

	case IPPROTO_UDP: {
		struct udphdr _udph, *uh;

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

3737 3738
		ad->u.net->sport = uh->source;
		ad->u.net->dport = uh->dest;
L
Linus Torvalds 已提交
3739 3740 3741
		break;
	}

J
James Morris 已提交
3742 3743 3744 3745 3746 3747 3748
	case IPPROTO_DCCP: {
		struct dccp_hdr _dccph, *dh;

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

3749 3750
		ad->u.net->sport = dh->dccph_sport;
		ad->u.net->dport = dh->dccph_dport;
J
James Morris 已提交
3751
		break;
3752
	}
J
James Morris 已提交
3753

L
Linus Torvalds 已提交
3754 3755 3756 3757 3758 3759 3760 3761 3762 3763
	/* includes fragments */
	default:
		break;
	}
out:
	return ret;
}

#endif /* IPV6 */

3764
static int selinux_parse_skb(struct sk_buff *skb, struct common_audit_data *ad,
3765
			     char **_addrp, int src, u8 *proto)
L
Linus Torvalds 已提交
3766
{
3767 3768
	char *addrp;
	int ret;
L
Linus Torvalds 已提交
3769

3770
	switch (ad->u.net->family) {
L
Linus Torvalds 已提交
3771
	case PF_INET:
3772
		ret = selinux_parse_skb_ipv4(skb, ad, proto);
3773 3774
		if (ret)
			goto parse_error;
3775 3776
		addrp = (char *)(src ? &ad->u.net->v4info.saddr :
				       &ad->u.net->v4info.daddr);
3777
		goto okay;
L
Linus Torvalds 已提交
3778 3779 3780

#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
	case PF_INET6:
3781
		ret = selinux_parse_skb_ipv6(skb, ad, proto);
3782 3783
		if (ret)
			goto parse_error;
3784 3785
		addrp = (char *)(src ? &ad->u.net->v6info.saddr :
				       &ad->u.net->v6info.daddr);
3786
		goto okay;
L
Linus Torvalds 已提交
3787 3788
#endif	/* IPV6 */
	default:
3789 3790
		addrp = NULL;
		goto okay;
L
Linus Torvalds 已提交
3791 3792
	}

3793 3794 3795 3796
parse_error:
	printk(KERN_WARNING
	       "SELinux: failure in selinux_parse_skb(),"
	       " unable to parse packet\n");
L
Linus Torvalds 已提交
3797
	return ret;
3798 3799 3800 3801 3802

okay:
	if (_addrp)
		*_addrp = addrp;
	return 0;
L
Linus Torvalds 已提交
3803 3804
}

3805
/**
3806
 * selinux_skb_peerlbl_sid - Determine the peer label of a packet
3807
 * @skb: the packet
3808
 * @family: protocol family
3809
 * @sid: the packet's peer label SID
3810 3811
 *
 * Description:
3812 3813 3814 3815 3816 3817
 * 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.
3818 3819
 *
 */
3820
static int selinux_skb_peerlbl_sid(struct sk_buff *skb, u16 family, u32 *sid)
3821
{
3822
	int err;
3823 3824
	u32 xfrm_sid;
	u32 nlbl_sid;
3825
	u32 nlbl_type;
3826

3827
	err = selinux_xfrm_skb_sid(skb, &xfrm_sid);
3828 3829 3830 3831 3832
	if (unlikely(err))
		return -EACCES;
	err = selinux_netlbl_skbuff_getsid(skb, family, &nlbl_type, &nlbl_sid);
	if (unlikely(err))
		return -EACCES;
3833

3834 3835 3836 3837 3838
	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");
3839
		return -EACCES;
3840
	}
3841 3842

	return 0;
3843 3844
}

3845 3846 3847 3848 3849 3850 3851 3852 3853 3854 3855 3856 3857 3858 3859 3860 3861 3862 3863 3864 3865 3866 3867 3868
/**
 * selinux_conn_sid - Determine the child socket label for a connection
 * @sk_sid: the parent socket's SID
 * @skb_sid: the packet's SID
 * @conn_sid: the resulting connection SID
 *
 * If @skb_sid is valid then the user:role:type information from @sk_sid is
 * combined with the MLS information from @skb_sid in order to create
 * @conn_sid.  If @skb_sid is not valid then then @conn_sid is simply a copy
 * of @sk_sid.  Returns zero on success, negative values on failure.
 *
 */
static int selinux_conn_sid(u32 sk_sid, u32 skb_sid, u32 *conn_sid)
{
	int err = 0;

	if (skb_sid != SECSID_NULL)
		err = security_sid_mls_copy(sk_sid, skb_sid, conn_sid);
	else
		*conn_sid = sk_sid;

	return err;
}

L
Linus Torvalds 已提交
3869
/* socket security operations */
3870

3871 3872
static int socket_sockcreate_sid(const struct task_security_struct *tsec,
				 u16 secclass, u32 *socksid)
3873
{
3874 3875 3876 3877 3878 3879 3880
	if (tsec->sockcreate_sid > SECSID_NULL) {
		*socksid = tsec->sockcreate_sid;
		return 0;
	}

	return security_transition_sid(tsec->sid, tsec->sid, secclass, NULL,
				       socksid);
3881 3882
}

3883
static int sock_has_perm(struct task_struct *task, struct sock *sk, u32 perms)
L
Linus Torvalds 已提交
3884
{
3885
	struct sk_security_struct *sksec = sk->sk_security;
3886
	struct common_audit_data ad;
3887
	struct lsm_network_audit net = {0,};
3888
	u32 tsid = task_sid(task);
L
Linus Torvalds 已提交
3889

3890 3891
	if (sksec->sid == SECINITSID_KERNEL)
		return 0;
L
Linus Torvalds 已提交
3892

3893
	ad.type = LSM_AUDIT_DATA_NET;
3894 3895
	ad.u.net = &net;
	ad.u.net->sk = sk;
L
Linus Torvalds 已提交
3896

3897
	return avc_has_perm(tsid, sksec->sid, sksec->sclass, perms, &ad);
L
Linus Torvalds 已提交
3898 3899 3900 3901 3902
}

static int selinux_socket_create(int family, int type,
				 int protocol, int kern)
{
3903
	const struct task_security_struct *tsec = current_security();
3904
	u32 newsid;
3905
	u16 secclass;
3906
	int rc;
L
Linus Torvalds 已提交
3907 3908

	if (kern)
3909
		return 0;
3910 3911

	secclass = socket_type_to_security_class(family, type, protocol);
3912 3913 3914 3915
	rc = socket_sockcreate_sid(tsec, secclass, &newsid);
	if (rc)
		return rc;

3916
	return avc_has_perm(tsec->sid, newsid, secclass, SOCKET__CREATE, NULL);
L
Linus Torvalds 已提交
3917 3918
}

V
Venkat Yekkirala 已提交
3919 3920
static int selinux_socket_post_create(struct socket *sock, int family,
				      int type, int protocol, int kern)
L
Linus Torvalds 已提交
3921
{
3922
	const struct task_security_struct *tsec = current_security();
3923
	struct inode_security_struct *isec = SOCK_INODE(sock)->i_security;
3924
	struct sk_security_struct *sksec;
3925 3926
	int err = 0;

3927 3928
	isec->sclass = socket_type_to_security_class(family, type, protocol);

3929 3930
	if (kern)
		isec->sid = SECINITSID_KERNEL;
3931 3932 3933 3934 3935
	else {
		err = socket_sockcreate_sid(tsec, isec->sclass, &(isec->sid));
		if (err)
			return err;
	}
3936

L
Linus Torvalds 已提交
3937 3938
	isec->initialized = 1;

3939 3940 3941
	if (sock->sk) {
		sksec = sock->sk->sk_security;
		sksec->sid = isec->sid;
3942
		sksec->sclass = isec->sclass;
3943
		err = selinux_netlbl_socket_post_create(sock->sk, family);
3944 3945
	}

V
Venkat Yekkirala 已提交
3946
	return err;
L
Linus Torvalds 已提交
3947 3948 3949 3950 3951 3952 3953 3954
}

/* 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)
{
3955
	struct sock *sk = sock->sk;
L
Linus Torvalds 已提交
3956 3957 3958
	u16 family;
	int err;

3959
	err = sock_has_perm(current, sk, SOCKET__BIND);
L
Linus Torvalds 已提交
3960 3961 3962 3963 3964
	if (err)
		goto out;

	/*
	 * If PF_INET or PF_INET6, check name_bind permission for the port.
3965 3966
	 * Multiple address binding for SCTP is not supported yet: we just
	 * check the first address now.
L
Linus Torvalds 已提交
3967
	 */
3968
	family = sk->sk_family;
L
Linus Torvalds 已提交
3969 3970
	if (family == PF_INET || family == PF_INET6) {
		char *addrp;
3971
		struct sk_security_struct *sksec = sk->sk_security;
3972
		struct common_audit_data ad;
3973
		struct lsm_network_audit net = {0,};
L
Linus Torvalds 已提交
3974 3975 3976
		struct sockaddr_in *addr4 = NULL;
		struct sockaddr_in6 *addr6 = NULL;
		unsigned short snum;
3977
		u32 sid, node_perm;
L
Linus Torvalds 已提交
3978 3979 3980 3981 3982 3983 3984 3985 3986 3987 3988

		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;
		}

3989 3990 3991
		if (snum) {
			int low, high;

3992
			inet_get_local_port_range(sock_net(sk), &low, &high);
3993 3994

			if (snum < max(PROT_SOCK, low) || snum > high) {
P
Paul Moore 已提交
3995 3996
				err = sel_netport_sid(sk->sk_protocol,
						      snum, &sid);
3997 3998
				if (err)
					goto out;
3999
				ad.type = LSM_AUDIT_DATA_NET;
4000 4001 4002
				ad.u.net = &net;
				ad.u.net->sport = htons(snum);
				ad.u.net->family = family;
4003 4004
				err = avc_has_perm(sksec->sid, sid,
						   sksec->sclass,
4005 4006 4007 4008
						   SOCKET__NAME_BIND, &ad);
				if (err)
					goto out;
			}
L
Linus Torvalds 已提交
4009
		}
4010

4011
		switch (sksec->sclass) {
4012
		case SECCLASS_TCP_SOCKET:
L
Linus Torvalds 已提交
4013 4014
			node_perm = TCP_SOCKET__NODE_BIND;
			break;
4015

4016
		case SECCLASS_UDP_SOCKET:
L
Linus Torvalds 已提交
4017 4018
			node_perm = UDP_SOCKET__NODE_BIND;
			break;
J
James Morris 已提交
4019 4020 4021 4022 4023

		case SECCLASS_DCCP_SOCKET:
			node_perm = DCCP_SOCKET__NODE_BIND;
			break;

L
Linus Torvalds 已提交
4024 4025 4026 4027
		default:
			node_perm = RAWIP_SOCKET__NODE_BIND;
			break;
		}
4028

4029
		err = sel_netnode_sid(addrp, family, &sid);
L
Linus Torvalds 已提交
4030 4031
		if (err)
			goto out;
4032

4033
		ad.type = LSM_AUDIT_DATA_NET;
4034 4035 4036
		ad.u.net = &net;
		ad.u.net->sport = htons(snum);
		ad.u.net->family = family;
L
Linus Torvalds 已提交
4037 4038

		if (family == PF_INET)
4039
			ad.u.net->v4info.saddr = addr4->sin_addr.s_addr;
L
Linus Torvalds 已提交
4040
		else
4041
			ad.u.net->v6info.saddr = addr6->sin6_addr;
L
Linus Torvalds 已提交
4042

4043 4044
		err = avc_has_perm(sksec->sid, sid,
				   sksec->sclass, node_perm, &ad);
L
Linus Torvalds 已提交
4045 4046 4047 4048 4049 4050 4051 4052 4053
		if (err)
			goto out;
	}
out:
	return err;
}

static int selinux_socket_connect(struct socket *sock, struct sockaddr *address, int addrlen)
{
4054
	struct sock *sk = sock->sk;
4055
	struct sk_security_struct *sksec = sk->sk_security;
L
Linus Torvalds 已提交
4056 4057
	int err;

4058
	err = sock_has_perm(current, sk, SOCKET__CONNECT);
L
Linus Torvalds 已提交
4059 4060 4061 4062
	if (err)
		return err;

	/*
J
James Morris 已提交
4063
	 * If a TCP or DCCP socket, check name_connect permission for the port.
L
Linus Torvalds 已提交
4064
	 */
4065 4066
	if (sksec->sclass == SECCLASS_TCP_SOCKET ||
	    sksec->sclass == SECCLASS_DCCP_SOCKET) {
4067
		struct common_audit_data ad;
4068
		struct lsm_network_audit net = {0,};
L
Linus Torvalds 已提交
4069 4070 4071
		struct sockaddr_in *addr4 = NULL;
		struct sockaddr_in6 *addr6 = NULL;
		unsigned short snum;
J
James Morris 已提交
4072
		u32 sid, perm;
L
Linus Torvalds 已提交
4073 4074 4075

		if (sk->sk_family == PF_INET) {
			addr4 = (struct sockaddr_in *)address;
4076
			if (addrlen < sizeof(struct sockaddr_in))
L
Linus Torvalds 已提交
4077 4078 4079 4080
				return -EINVAL;
			snum = ntohs(addr4->sin_port);
		} else {
			addr6 = (struct sockaddr_in6 *)address;
4081
			if (addrlen < SIN6_LEN_RFC2133)
L
Linus Torvalds 已提交
4082 4083 4084 4085
				return -EINVAL;
			snum = ntohs(addr6->sin6_port);
		}

P
Paul Moore 已提交
4086
		err = sel_netport_sid(sk->sk_protocol, snum, &sid);
L
Linus Torvalds 已提交
4087 4088 4089
		if (err)
			goto out;

4090
		perm = (sksec->sclass == SECCLASS_TCP_SOCKET) ?
J
James Morris 已提交
4091 4092
		       TCP_SOCKET__NAME_CONNECT : DCCP_SOCKET__NAME_CONNECT;

4093
		ad.type = LSM_AUDIT_DATA_NET;
4094 4095 4096
		ad.u.net = &net;
		ad.u.net->dport = htons(snum);
		ad.u.net->family = sk->sk_family;
4097
		err = avc_has_perm(sksec->sid, sid, sksec->sclass, perm, &ad);
L
Linus Torvalds 已提交
4098 4099 4100 4101
		if (err)
			goto out;
	}

4102 4103
	err = selinux_netlbl_socket_connect(sk, address);

L
Linus Torvalds 已提交
4104 4105 4106 4107 4108 4109
out:
	return err;
}

static int selinux_socket_listen(struct socket *sock, int backlog)
{
4110
	return sock_has_perm(current, sock->sk, SOCKET__LISTEN);
L
Linus Torvalds 已提交
4111 4112 4113 4114 4115 4116 4117 4118
}

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

4119
	err = sock_has_perm(current, sock->sk, SOCKET__ACCEPT);
L
Linus Torvalds 已提交
4120 4121 4122 4123 4124 4125 4126 4127 4128 4129 4130 4131 4132 4133
	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,
4134
				  int size)
L
Linus Torvalds 已提交
4135
{
4136
	return sock_has_perm(current, sock->sk, SOCKET__WRITE);
L
Linus Torvalds 已提交
4137 4138 4139 4140 4141
}

static int selinux_socket_recvmsg(struct socket *sock, struct msghdr *msg,
				  int size, int flags)
{
4142
	return sock_has_perm(current, sock->sk, SOCKET__READ);
L
Linus Torvalds 已提交
4143 4144 4145 4146
}

static int selinux_socket_getsockname(struct socket *sock)
{
4147
	return sock_has_perm(current, sock->sk, SOCKET__GETATTR);
L
Linus Torvalds 已提交
4148 4149 4150 4151
}

static int selinux_socket_getpeername(struct socket *sock)
{
4152
	return sock_has_perm(current, sock->sk, SOCKET__GETATTR);
L
Linus Torvalds 已提交
4153 4154
}

4155
static int selinux_socket_setsockopt(struct socket *sock, int level, int optname)
L
Linus Torvalds 已提交
4156
{
4157 4158
	int err;

4159
	err = sock_has_perm(current, sock->sk, SOCKET__SETOPT);
4160 4161 4162 4163
	if (err)
		return err;

	return selinux_netlbl_socket_setsockopt(sock, level, optname);
L
Linus Torvalds 已提交
4164 4165 4166 4167 4168
}

static int selinux_socket_getsockopt(struct socket *sock, int level,
				     int optname)
{
4169
	return sock_has_perm(current, sock->sk, SOCKET__GETOPT);
L
Linus Torvalds 已提交
4170 4171 4172 4173
}

static int selinux_socket_shutdown(struct socket *sock, int how)
{
4174
	return sock_has_perm(current, sock->sk, SOCKET__SHUTDOWN);
L
Linus Torvalds 已提交
4175 4176
}

4177 4178
static int selinux_socket_unix_stream_connect(struct sock *sock,
					      struct sock *other,
L
Linus Torvalds 已提交
4179 4180
					      struct sock *newsk)
{
4181 4182
	struct sk_security_struct *sksec_sock = sock->sk_security;
	struct sk_security_struct *sksec_other = other->sk_security;
4183
	struct sk_security_struct *sksec_new = newsk->sk_security;
4184
	struct common_audit_data ad;
4185
	struct lsm_network_audit net = {0,};
L
Linus Torvalds 已提交
4186 4187
	int err;

4188
	ad.type = LSM_AUDIT_DATA_NET;
4189 4190
	ad.u.net = &net;
	ad.u.net->sk = other;
L
Linus Torvalds 已提交
4191

4192 4193
	err = avc_has_perm(sksec_sock->sid, sksec_other->sid,
			   sksec_other->sclass,
L
Linus Torvalds 已提交
4194 4195 4196 4197 4198
			   UNIX_STREAM_SOCKET__CONNECTTO, &ad);
	if (err)
		return err;

	/* server child socket */
4199 4200 4201 4202 4203
	sksec_new->peer_sid = sksec_sock->sid;
	err = security_sid_mls_copy(sksec_other->sid, sksec_sock->sid,
				    &sksec_new->sid);
	if (err)
		return err;
4204

4205 4206 4207 4208
	/* connecting socket */
	sksec_sock->peer_sid = sksec_new->sid;

	return 0;
L
Linus Torvalds 已提交
4209 4210 4211 4212 4213
}

static int selinux_socket_unix_may_send(struct socket *sock,
					struct socket *other)
{
4214 4215
	struct sk_security_struct *ssec = sock->sk->sk_security;
	struct sk_security_struct *osec = other->sk->sk_security;
4216
	struct common_audit_data ad;
4217
	struct lsm_network_audit net = {0,};
L
Linus Torvalds 已提交
4218

4219
	ad.type = LSM_AUDIT_DATA_NET;
4220 4221
	ad.u.net = &net;
	ad.u.net->sk = other->sk;
L
Linus Torvalds 已提交
4222

4223 4224
	return avc_has_perm(ssec->sid, osec->sid, osec->sclass, SOCKET__SENDTO,
			    &ad);
L
Linus Torvalds 已提交
4225 4226
}

4227 4228
static int selinux_inet_sys_rcv_skb(int ifindex, char *addrp, u16 family,
				    u32 peer_sid,
4229
				    struct common_audit_data *ad)
4230 4231 4232 4233 4234 4235 4236 4237 4238 4239 4240 4241 4242 4243 4244 4245 4246 4247 4248 4249
{
	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);
}

4250
static int selinux_sock_rcv_skb_compat(struct sock *sk, struct sk_buff *skb,
4251
				       u16 family)
4252
{
4253
	int err = 0;
4254 4255
	struct sk_security_struct *sksec = sk->sk_security;
	u32 sk_sid = sksec->sid;
4256
	struct common_audit_data ad;
4257
	struct lsm_network_audit net = {0,};
4258 4259
	char *addrp;

4260
	ad.type = LSM_AUDIT_DATA_NET;
4261 4262 4263
	ad.u.net = &net;
	ad.u.net->netif = skb->skb_iif;
	ad.u.net->family = family;
4264 4265 4266
	err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL);
	if (err)
		return err;
L
Linus Torvalds 已提交
4267

4268
	if (selinux_secmark_enabled()) {
4269
		err = avc_has_perm(sk_sid, skb->secmark, SECCLASS_PACKET,
4270
				   PACKET__RECV, &ad);
4271 4272 4273
		if (err)
			return err;
	}
4274

4275 4276 4277 4278
	err = selinux_netlbl_sock_rcv_skb(sksec, skb, family, &ad);
	if (err)
		return err;
	err = selinux_xfrm_sock_rcv_skb(sksec->sid, skb, &ad);
4279

4280 4281 4282 4283 4284
	return err;
}

static int selinux_socket_sock_rcv_skb(struct sock *sk, struct sk_buff *skb)
{
4285
	int err;
4286
	struct sk_security_struct *sksec = sk->sk_security;
4287 4288
	u16 family = sk->sk_family;
	u32 sk_sid = sksec->sid;
4289
	struct common_audit_data ad;
4290
	struct lsm_network_audit net = {0,};
4291
	char *addrp;
4292 4293
	u8 secmark_active;
	u8 peerlbl_active;
4294 4295

	if (family != PF_INET && family != PF_INET6)
4296
		return 0;
4297 4298

	/* Handle mapped IPv4 packets arriving via IPv6 sockets */
A
Al Viro 已提交
4299
	if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
4300 4301
		family = PF_INET;

4302 4303 4304 4305
	/* 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. */
4306
	if (!selinux_policycap_netpeer)
4307 4308 4309
		return selinux_sock_rcv_skb_compat(sk, skb, family);

	secmark_active = selinux_secmark_enabled();
4310
	peerlbl_active = selinux_peerlbl_enabled();
4311 4312 4313
	if (!secmark_active && !peerlbl_active)
		return 0;

4314
	ad.type = LSM_AUDIT_DATA_NET;
4315 4316 4317
	ad.u.net = &net;
	ad.u.net->netif = skb->skb_iif;
	ad.u.net->family = family;
4318
	err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL);
4319
	if (err)
4320
		return err;
4321

4322
	if (peerlbl_active) {
4323 4324 4325
		u32 peer_sid;

		err = selinux_skb_peerlbl_sid(skb, family, &peer_sid);
4326 4327
		if (err)
			return err;
4328
		err = selinux_inet_sys_rcv_skb(skb->skb_iif, addrp, family,
4329
					       peer_sid, &ad);
4330 4331
		if (err) {
			selinux_netlbl_err(skb, err, 0);
4332
			return err;
4333
		}
4334 4335
		err = avc_has_perm(sk_sid, peer_sid, SECCLASS_PEER,
				   PEER__RECV, &ad);
C
Chad Hanson 已提交
4336
		if (err) {
4337
			selinux_netlbl_err(skb, err, 0);
C
Chad Hanson 已提交
4338 4339
			return err;
		}
4340 4341
	}

4342
	if (secmark_active) {
4343 4344 4345 4346 4347 4348
		err = avc_has_perm(sk_sid, skb->secmark, SECCLASS_PACKET,
				   PACKET__RECV, &ad);
		if (err)
			return err;
	}

4349
	return err;
L
Linus Torvalds 已提交
4350 4351
}

C
Catherine Zhang 已提交
4352 4353
static int selinux_socket_getpeersec_stream(struct socket *sock, char __user *optval,
					    int __user *optlen, unsigned len)
L
Linus Torvalds 已提交
4354 4355 4356 4357
{
	int err = 0;
	char *scontext;
	u32 scontext_len;
4358
	struct sk_security_struct *sksec = sock->sk->sk_security;
4359
	u32 peer_sid = SECSID_NULL;
L
Linus Torvalds 已提交
4360

4361 4362
	if (sksec->sclass == SECCLASS_UNIX_STREAM_SOCKET ||
	    sksec->sclass == SECCLASS_TCP_SOCKET)
4363
		peer_sid = sksec->peer_sid;
4364 4365
	if (peer_sid == SECSID_NULL)
		return -ENOPROTOOPT;
L
Linus Torvalds 已提交
4366

C
Catherine Zhang 已提交
4367
	err = security_sid_to_context(peer_sid, &scontext, &scontext_len);
L
Linus Torvalds 已提交
4368
	if (err)
4369
		return err;
L
Linus Torvalds 已提交
4370 4371 4372 4373 4374 4375 4376 4377 4378 4379 4380 4381 4382 4383 4384 4385

	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);
	return err;
}

4386
static int selinux_socket_getpeersec_dgram(struct socket *sock, struct sk_buff *skb, u32 *secid)
C
Catherine Zhang 已提交
4387
{
4388
	u32 peer_secid = SECSID_NULL;
4389
	u16 family;
C
Catherine Zhang 已提交
4390

4391 4392 4393 4394 4395
	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)
4396 4397 4398 4399 4400
		family = sock->sk->sk_family;
	else
		goto out;

	if (sock && family == PF_UNIX)
4401
		selinux_inode_getsecid(SOCK_INODE(sock), &peer_secid);
4402
	else if (skb)
4403
		selinux_skb_peerlbl_sid(skb, family, &peer_secid);
C
Catherine Zhang 已提交
4404

4405
out:
4406
	*secid = peer_secid;
4407 4408 4409
	if (peer_secid == SECSID_NULL)
		return -EINVAL;
	return 0;
C
Catherine Zhang 已提交
4410 4411
}

A
Al Viro 已提交
4412
static int selinux_sk_alloc_security(struct sock *sk, int family, gfp_t priority)
L
Linus Torvalds 已提交
4413
{
4414 4415 4416 4417 4418 4419 4420 4421 4422 4423 4424 4425
	struct sk_security_struct *sksec;

	sksec = kzalloc(sizeof(*sksec), priority);
	if (!sksec)
		return -ENOMEM;

	sksec->peer_sid = SECINITSID_UNLABELED;
	sksec->sid = SECINITSID_UNLABELED;
	selinux_netlbl_sk_security_reset(sksec);
	sk->sk_security = sksec;

	return 0;
L
Linus Torvalds 已提交
4426 4427 4428 4429
}

static void selinux_sk_free_security(struct sock *sk)
{
4430 4431 4432 4433 4434
	struct sk_security_struct *sksec = sk->sk_security;

	sk->sk_security = NULL;
	selinux_netlbl_sk_security_free(sksec);
	kfree(sksec);
L
Linus Torvalds 已提交
4435 4436
}

4437
static void selinux_sk_clone_security(const struct sock *sk, struct sock *newsk)
4438
{
4439 4440
	struct sk_security_struct *sksec = sk->sk_security;
	struct sk_security_struct *newsksec = newsk->sk_security;
4441

4442 4443 4444
	newsksec->sid = sksec->sid;
	newsksec->peer_sid = sksec->peer_sid;
	newsksec->sclass = sksec->sclass;
4445

4446
	selinux_netlbl_sk_security_reset(newsksec);
4447 4448
}

V
Venkat Yekkirala 已提交
4449
static void selinux_sk_getsecid(struct sock *sk, u32 *secid)
4450
{
4451
	if (!sk)
V
Venkat Yekkirala 已提交
4452
		*secid = SECINITSID_ANY_SOCKET;
4453 4454
	else {
		struct sk_security_struct *sksec = sk->sk_security;
4455

V
Venkat Yekkirala 已提交
4456
		*secid = sksec->sid;
4457
	}
4458 4459
}

4460
static void selinux_sock_graft(struct sock *sk, struct socket *parent)
4461 4462 4463 4464
{
	struct inode_security_struct *isec = SOCK_INODE(parent)->i_security;
	struct sk_security_struct *sksec = sk->sk_security;

4465 4466 4467
	if (sk->sk_family == PF_INET || sk->sk_family == PF_INET6 ||
	    sk->sk_family == PF_UNIX)
		isec->sid = sksec->sid;
4468
	sksec->sclass = isec->sclass;
4469 4470
}

4471 4472
static int selinux_inet_conn_request(struct sock *sk, struct sk_buff *skb,
				     struct request_sock *req)
4473 4474 4475
{
	struct sk_security_struct *sksec = sk->sk_security;
	int err;
4476
	u16 family = req->rsk_ops->family;
4477
	u32 connsid;
4478 4479
	u32 peersid;

4480
	err = selinux_skb_peerlbl_sid(skb, family, &peersid);
4481 4482
	if (err)
		return err;
4483 4484 4485 4486 4487
	err = selinux_conn_sid(sksec->sid, peersid, &connsid);
	if (err)
		return err;
	req->secid = connsid;
	req->peer_secid = peersid;
4488

4489
	return selinux_netlbl_inet_conn_request(req, family);
4490 4491
}

4492 4493
static void selinux_inet_csk_clone(struct sock *newsk,
				   const struct request_sock *req)
4494 4495 4496 4497
{
	struct sk_security_struct *newsksec = newsk->sk_security;

	newsksec->sid = req->secid;
4498
	newsksec->peer_sid = req->peer_secid;
4499 4500 4501 4502
	/* 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. */
4503

P
Paul Moore 已提交
4504 4505
	/* We don't need to take any sort of lock here as we are the only
	 * thread with access to newsksec */
4506
	selinux_netlbl_inet_csk_clone(newsk, req->rsk_ops->family);
4507 4508
}

4509
static void selinux_inet_conn_established(struct sock *sk, struct sk_buff *skb)
4510
{
4511
	u16 family = sk->sk_family;
4512 4513
	struct sk_security_struct *sksec = sk->sk_security;

4514 4515 4516 4517 4518
	/* 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);
4519 4520
}

4521 4522 4523 4524 4525
static void selinux_skb_owned_by(struct sk_buff *skb, struct sock *sk)
{
	skb_set_owner_w(skb, sk);
}

4526 4527 4528 4529 4530 4531 4532 4533 4534 4535 4536 4537 4538 4539 4540 4541 4542 4543 4544 4545 4546
static int selinux_secmark_relabel_packet(u32 sid)
{
	const struct task_security_struct *__tsec;
	u32 tsid;

	__tsec = current_security();
	tsid = __tsec->sid;

	return avc_has_perm(tsid, sid, SECCLASS_PACKET, PACKET__RELABELTO, NULL);
}

static void selinux_secmark_refcount_inc(void)
{
	atomic_inc(&selinux_secmark_refcount);
}

static void selinux_secmark_refcount_dec(void)
{
	atomic_dec(&selinux_secmark_refcount);
}

4547 4548
static void selinux_req_classify_flow(const struct request_sock *req,
				      struct flowi *fl)
4549
{
4550
	fl->flowi_secid = req->secid;
4551 4552
}

4553 4554 4555 4556 4557 4558 4559 4560 4561 4562 4563 4564 4565 4566 4567 4568 4569 4570
static int selinux_tun_dev_alloc_security(void **security)
{
	struct tun_security_struct *tunsec;

	tunsec = kzalloc(sizeof(*tunsec), GFP_KERNEL);
	if (!tunsec)
		return -ENOMEM;
	tunsec->sid = current_sid();

	*security = tunsec;
	return 0;
}

static void selinux_tun_dev_free_security(void *security)
{
	kfree(security);
}

4571 4572 4573 4574 4575 4576 4577 4578 4579 4580 4581 4582 4583 4584 4585
static int selinux_tun_dev_create(void)
{
	u32 sid = current_sid();

	/* we aren't taking into account the "sockcreate" SID since the socket
	 * that is being created here is not a socket in the traditional sense,
	 * instead it is a private sock, accessible only to the kernel, and
	 * representing a wide range of network traffic spanning multiple
	 * connections unlike traditional sockets - check the TUN driver to
	 * get a better understanding of why this socket is special */

	return avc_has_perm(sid, sid, SECCLASS_TUN_SOCKET, TUN_SOCKET__CREATE,
			    NULL);
}

4586
static int selinux_tun_dev_attach_queue(void *security)
4587
{
4588 4589 4590 4591 4592 4593 4594 4595 4596
	struct tun_security_struct *tunsec = security;

	return avc_has_perm(current_sid(), tunsec->sid, SECCLASS_TUN_SOCKET,
			    TUN_SOCKET__ATTACH_QUEUE, NULL);
}

static int selinux_tun_dev_attach(struct sock *sk, void *security)
{
	struct tun_security_struct *tunsec = security;
4597 4598 4599 4600 4601 4602 4603 4604 4605
	struct sk_security_struct *sksec = sk->sk_security;

	/* we don't currently perform any NetLabel based labeling here and it
	 * isn't clear that we would want to do so anyway; while we could apply
	 * labeling without the support of the TUN user the resulting labeled
	 * traffic from the other end of the connection would almost certainly
	 * cause confusion to the TUN user that had no idea network labeling
	 * protocols were being used */

4606
	sksec->sid = tunsec->sid;
4607
	sksec->sclass = SECCLASS_TUN_SOCKET;
4608 4609

	return 0;
4610 4611
}

4612
static int selinux_tun_dev_open(void *security)
4613
{
4614
	struct tun_security_struct *tunsec = security;
4615 4616 4617
	u32 sid = current_sid();
	int err;

4618
	err = avc_has_perm(sid, tunsec->sid, SECCLASS_TUN_SOCKET,
4619 4620 4621 4622 4623 4624 4625
			   TUN_SOCKET__RELABELFROM, NULL);
	if (err)
		return err;
	err = avc_has_perm(sid, sid, SECCLASS_TUN_SOCKET,
			   TUN_SOCKET__RELABELTO, NULL);
	if (err)
		return err;
4626
	tunsec->sid = sid;
4627 4628 4629 4630

	return 0;
}

L
Linus Torvalds 已提交
4631 4632 4633 4634 4635
static int selinux_nlmsg_perm(struct sock *sk, struct sk_buff *skb)
{
	int err = 0;
	u32 perm;
	struct nlmsghdr *nlh;
4636
	struct sk_security_struct *sksec = sk->sk_security;
4637

4638
	if (skb->len < NLMSG_HDRLEN) {
L
Linus Torvalds 已提交
4639 4640 4641
		err = -EINVAL;
		goto out;
	}
4642
	nlh = nlmsg_hdr(skb);
4643

4644
	err = selinux_nlmsg_lookup(sksec->sclass, nlh->nlmsg_type, &perm);
L
Linus Torvalds 已提交
4645 4646
	if (err) {
		if (err == -EINVAL) {
4647
			audit_log(current->audit_context, GFP_KERNEL, AUDIT_SELINUX_ERR,
L
Linus Torvalds 已提交
4648 4649
				  "SELinux:  unrecognized netlink message"
				  " type=%hu for sclass=%hu\n",
4650
				  nlh->nlmsg_type, sksec->sclass);
4651
			if (!selinux_enforcing || security_get_allow_unknown())
L
Linus Torvalds 已提交
4652 4653 4654 4655 4656 4657 4658 4659 4660
				err = 0;
		}

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

4661
	err = sock_has_perm(current, sk, perm);
L
Linus Torvalds 已提交
4662 4663 4664 4665 4666 4667
out:
	return err;
}

#ifdef CONFIG_NETFILTER

4668 4669
static unsigned int selinux_ip_forward(struct sk_buff *skb, int ifindex,
				       u16 family)
L
Linus Torvalds 已提交
4670
{
4671
	int err;
4672 4673
	char *addrp;
	u32 peer_sid;
4674
	struct common_audit_data ad;
4675
	struct lsm_network_audit net = {0,};
4676
	u8 secmark_active;
4677
	u8 netlbl_active;
4678
	u8 peerlbl_active;
4679

4680 4681
	if (!selinux_policycap_netpeer)
		return NF_ACCEPT;
4682

4683
	secmark_active = selinux_secmark_enabled();
4684
	netlbl_active = netlbl_enabled();
4685
	peerlbl_active = selinux_peerlbl_enabled();
4686 4687
	if (!secmark_active && !peerlbl_active)
		return NF_ACCEPT;
4688

4689 4690 4691
	if (selinux_skb_peerlbl_sid(skb, family, &peer_sid) != 0)
		return NF_DROP;

4692
	ad.type = LSM_AUDIT_DATA_NET;
4693 4694 4695
	ad.u.net = &net;
	ad.u.net->netif = ifindex;
	ad.u.net->family = family;
4696 4697 4698
	if (selinux_parse_skb(skb, &ad, &addrp, 1, NULL) != 0)
		return NF_DROP;

4699 4700 4701 4702 4703
	if (peerlbl_active) {
		err = selinux_inet_sys_rcv_skb(ifindex, addrp, family,
					       peer_sid, &ad);
		if (err) {
			selinux_netlbl_err(skb, err, 1);
4704
			return NF_DROP;
4705 4706
		}
	}
4707 4708 4709 4710 4711 4712

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

4713 4714 4715 4716 4717 4718 4719 4720
	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;

4721 4722 4723
	return NF_ACCEPT;
}

4724
static unsigned int selinux_ipv4_forward(const struct nf_hook_ops *ops,
4725 4726 4727 4728 4729 4730 4731 4732 4733
					 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)
4734
static unsigned int selinux_ipv6_forward(const struct nf_hook_ops *ops,
4735 4736 4737 4738 4739 4740 4741 4742 4743
					 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 */

4744 4745 4746
static unsigned int selinux_ip_output(struct sk_buff *skb,
				      u16 family)
{
4747
	struct sock *sk;
4748 4749 4750 4751 4752 4753 4754 4755
	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 */
4756 4757 4758 4759 4760 4761 4762 4763 4764 4765 4766 4767 4768 4769 4770 4771 4772 4773 4774 4775 4776
	sk = skb->sk;
	if (sk) {
		struct sk_security_struct *sksec;

		if (sk->sk_state == TCP_LISTEN)
			/* if the socket is the listening state then this
			 * packet is a SYN-ACK packet which means it needs to
			 * be labeled based on the connection/request_sock and
			 * not the parent socket.  unfortunately, we can't
			 * lookup the request_sock yet as it isn't queued on
			 * the parent socket until after the SYN-ACK is sent.
			 * the "solution" is to simply pass the packet as-is
			 * as any IP option based labeling should be copied
			 * from the initial connection request (in the IP
			 * layer).  it is far from ideal, but until we get a
			 * security label in the packet itself this is the
			 * best we can do. */
			return NF_ACCEPT;

		/* standard practice, label using the parent socket */
		sksec = sk->sk_security;
4777 4778 4779 4780 4781 4782 4783 4784 4785
		sid = sksec->sid;
	} else
		sid = SECINITSID_KERNEL;
	if (selinux_netlbl_skbuff_setsid(skb, family, sid) != 0)
		return NF_DROP;

	return NF_ACCEPT;
}

4786
static unsigned int selinux_ipv4_output(const struct nf_hook_ops *ops,
4787 4788 4789 4790 4791 4792 4793 4794
					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);
}

4795 4796
static unsigned int selinux_ip_postroute_compat(struct sk_buff *skb,
						int ifindex,
4797
						u16 family)
4798 4799 4800
{
	struct sock *sk = skb->sk;
	struct sk_security_struct *sksec;
4801
	struct common_audit_data ad;
4802
	struct lsm_network_audit net = {0,};
4803 4804
	char *addrp;
	u8 proto;
L
Linus Torvalds 已提交
4805

4806 4807 4808 4809
	if (sk == NULL)
		return NF_ACCEPT;
	sksec = sk->sk_security;

4810
	ad.type = LSM_AUDIT_DATA_NET;
4811 4812 4813
	ad.u.net = &net;
	ad.u.net->netif = ifindex;
	ad.u.net->family = family;
4814 4815 4816
	if (selinux_parse_skb(skb, &ad, &addrp, 0, &proto))
		return NF_DROP;

4817
	if (selinux_secmark_enabled())
4818
		if (avc_has_perm(sksec->sid, skb->secmark,
4819
				 SECCLASS_PACKET, PACKET__SEND, &ad))
4820
			return NF_DROP_ERR(-ECONNREFUSED);
4821

4822 4823
	if (selinux_xfrm_postroute_last(sksec->sid, skb, &ad, proto))
		return NF_DROP_ERR(-ECONNREFUSED);
4824 4825

	return NF_ACCEPT;
4826 4827
}

4828 4829
static unsigned int selinux_ip_postroute(struct sk_buff *skb, int ifindex,
					 u16 family)
4830
{
4831 4832
	u32 secmark_perm;
	u32 peer_sid;
4833
	struct sock *sk;
4834
	struct common_audit_data ad;
4835
	struct lsm_network_audit net = {0,};
4836 4837 4838
	char *addrp;
	u8 secmark_active;
	u8 peerlbl_active;
4839

4840 4841 4842 4843
	/* 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. */
4844
	if (!selinux_policycap_netpeer)
4845
		return selinux_ip_postroute_compat(skb, ifindex, family);
4846 4847 4848 4849 4850 4851 4852 4853

	secmark_active = selinux_secmark_enabled();
	peerlbl_active = selinux_peerlbl_enabled();
	if (!secmark_active && !peerlbl_active)
		return NF_ACCEPT;

	sk = skb->sk;

4854
#ifdef CONFIG_XFRM
4855 4856 4857 4858 4859
	/* 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
4860 4861 4862 4863 4864 4865 4866 4867
	 *       is NULL, in this case go ahead and apply access control.
	 * NOTE: if this is a local socket (skb->sk != NULL) that is in the
	 *       TCP listening state we cannot wait until the XFRM processing
	 *       is done as we will miss out on the SA label if we do;
	 *       unfortunately, this means more work, but it is only once per
	 *       connection. */
	if (skb_dst(skb) != NULL && skb_dst(skb)->xfrm != NULL &&
	    !(sk != NULL && sk->sk_state == TCP_LISTEN))
4868
		return NF_ACCEPT;
4869
#endif
4870

4871
	if (sk == NULL) {
4872 4873 4874 4875
		/* Without an associated socket the packet is either coming
		 * from the kernel or it is being forwarded; check the packet
		 * to determine which and if the packet is being forwarded
		 * query the packet directly to determine the security label. */
4876 4877
		if (skb->skb_iif) {
			secmark_perm = PACKET__FORWARD_OUT;
4878
			if (selinux_skb_peerlbl_sid(skb, family, &peer_sid))
4879
				return NF_DROP;
4880 4881
		} else {
			secmark_perm = PACKET__SEND;
4882
			peer_sid = SECINITSID_KERNEL;
4883
		}
4884 4885 4886 4887 4888 4889 4890 4891 4892 4893 4894 4895 4896 4897
	} else if (sk->sk_state == TCP_LISTEN) {
		/* Locally generated packet but the associated socket is in the
		 * listening state which means this is a SYN-ACK packet.  In
		 * this particular case the correct security label is assigned
		 * to the connection/request_sock but unfortunately we can't
		 * query the request_sock as it isn't queued on the parent
		 * socket until after the SYN-ACK packet is sent; the only
		 * viable choice is to regenerate the label like we do in
		 * selinux_inet_conn_request().  See also selinux_ip_output()
		 * for similar problems. */
		u32 skb_sid;
		struct sk_security_struct *sksec = sk->sk_security;
		if (selinux_skb_peerlbl_sid(skb, family, &skb_sid))
			return NF_DROP;
4898 4899 4900 4901 4902 4903 4904 4905 4906 4907 4908 4909 4910 4911 4912 4913 4914 4915 4916
		/* At this point, if the returned skb peerlbl is SECSID_NULL
		 * and the packet has been through at least one XFRM
		 * transformation then we must be dealing with the "final"
		 * form of labeled IPsec packet; since we've already applied
		 * all of our access controls on this packet we can safely
		 * pass the packet. */
		if (skb_sid == SECSID_NULL) {
			switch (family) {
			case PF_INET:
				if (IPCB(skb)->flags & IPSKB_XFRM_TRANSFORMED)
					return NF_ACCEPT;
				break;
			case PF_INET6:
				if (IP6CB(skb)->flags & IP6SKB_XFRM_TRANSFORMED)
					return NF_ACCEPT;
			default:
				return NF_DROP_ERR(-ECONNREFUSED);
			}
		}
4917 4918 4919
		if (selinux_conn_sid(sksec->sid, skb_sid, &peer_sid))
			return NF_DROP;
		secmark_perm = PACKET__SEND;
4920
	} else {
4921 4922
		/* Locally generated packet, fetch the security label from the
		 * associated socket. */
4923 4924 4925 4926
		struct sk_security_struct *sksec = sk->sk_security;
		peer_sid = sksec->sid;
		secmark_perm = PACKET__SEND;
	}
4927

4928
	ad.type = LSM_AUDIT_DATA_NET;
4929 4930 4931
	ad.u.net = &net;
	ad.u.net->netif = ifindex;
	ad.u.net->family = family;
4932
	if (selinux_parse_skb(skb, &ad, &addrp, 0, NULL))
4933
		return NF_DROP;
4934

4935 4936 4937
	if (secmark_active)
		if (avc_has_perm(peer_sid, skb->secmark,
				 SECCLASS_PACKET, secmark_perm, &ad))
4938
			return NF_DROP_ERR(-ECONNREFUSED);
4939 4940 4941 4942 4943 4944

	if (peerlbl_active) {
		u32 if_sid;
		u32 node_sid;

		if (sel_netif_sid(ifindex, &if_sid))
4945
			return NF_DROP;
4946 4947
		if (avc_has_perm(peer_sid, if_sid,
				 SECCLASS_NETIF, NETIF__EGRESS, &ad))
4948
			return NF_DROP_ERR(-ECONNREFUSED);
4949 4950

		if (sel_netnode_sid(addrp, family, &node_sid))
4951
			return NF_DROP;
4952 4953
		if (avc_has_perm(peer_sid, node_sid,
				 SECCLASS_NODE, NODE__SENDTO, &ad))
4954
			return NF_DROP_ERR(-ECONNREFUSED);
4955
	}
4956

4957
	return NF_ACCEPT;
L
Linus Torvalds 已提交
4958 4959
}

4960
static unsigned int selinux_ipv4_postroute(const struct nf_hook_ops *ops,
4961 4962 4963 4964
					   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
4965
{
4966
	return selinux_ip_postroute(skb, out->ifindex, PF_INET);
L
Linus Torvalds 已提交
4967 4968 4969
}

#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
4970
static unsigned int selinux_ipv6_postroute(const struct nf_hook_ops *ops,
4971 4972 4973 4974
					   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
4975
{
4976
	return selinux_ip_postroute(skb, out->ifindex, PF_INET6);
L
Linus Torvalds 已提交
4977 4978 4979 4980 4981 4982 4983 4984 4985
}
#endif	/* IPV6 */

#endif	/* CONFIG_NETFILTER */

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

4986
	err = cap_netlink_send(sk, skb);
L
Linus Torvalds 已提交
4987 4988 4989
	if (err)
		return err;

4990
	return selinux_nlmsg_perm(sk, skb);
L
Linus Torvalds 已提交
4991 4992 4993 4994 4995 4996 4997
}

static int ipc_alloc_security(struct task_struct *task,
			      struct kern_ipc_perm *perm,
			      u16 sclass)
{
	struct ipc_security_struct *isec;
4998
	u32 sid;
L
Linus Torvalds 已提交
4999

J
James Morris 已提交
5000
	isec = kzalloc(sizeof(struct ipc_security_struct), GFP_KERNEL);
L
Linus Torvalds 已提交
5001 5002 5003
	if (!isec)
		return -ENOMEM;

5004
	sid = task_sid(task);
L
Linus Torvalds 已提交
5005
	isec->sclass = sclass;
5006
	isec->sid = sid;
L
Linus Torvalds 已提交
5007 5008 5009 5010 5011 5012 5013 5014 5015 5016 5017 5018 5019 5020 5021 5022
	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
5023
	msec = kzalloc(sizeof(struct msg_security_struct), GFP_KERNEL);
L
Linus Torvalds 已提交
5024 5025 5026 5027 5028 5029 5030 5031 5032 5033 5034 5035 5036 5037 5038 5039 5040 5041
	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,
5042
			u32 perms)
L
Linus Torvalds 已提交
5043 5044
{
	struct ipc_security_struct *isec;
5045
	struct common_audit_data ad;
5046
	u32 sid = current_sid();
L
Linus Torvalds 已提交
5047 5048 5049

	isec = ipc_perms->security;

5050
	ad.type = LSM_AUDIT_DATA_IPC;
L
Linus Torvalds 已提交
5051 5052
	ad.u.ipc_id = ipc_perms->key;

5053
	return avc_has_perm(sid, isec->sid, isec->sclass, perms, &ad);
L
Linus Torvalds 已提交
5054 5055 5056 5057 5058 5059 5060 5061 5062 5063 5064 5065 5066 5067 5068 5069
}

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;
5070
	struct common_audit_data ad;
5071
	u32 sid = current_sid();
L
Linus Torvalds 已提交
5072 5073 5074 5075 5076 5077 5078 5079
	int rc;

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

	isec = msq->q_perm.security;

5080
	ad.type = LSM_AUDIT_DATA_IPC;
5081
	ad.u.ipc_id = msq->q_perm.key;
L
Linus Torvalds 已提交
5082

5083
	rc = avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
L
Linus Torvalds 已提交
5084 5085 5086 5087 5088 5089 5090 5091 5092 5093 5094 5095 5096 5097 5098 5099
			  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;
5100
	struct common_audit_data ad;
5101
	u32 sid = current_sid();
L
Linus Torvalds 已提交
5102 5103 5104

	isec = msq->q_perm.security;

5105
	ad.type = LSM_AUDIT_DATA_IPC;
L
Linus Torvalds 已提交
5106 5107
	ad.u.ipc_id = msq->q_perm.key;

5108
	return avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
L
Linus Torvalds 已提交
5109 5110 5111 5112 5113 5114 5115 5116
			    MSGQ__ASSOCIATE, &ad);
}

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

5117
	switch (cmd) {
L
Linus Torvalds 已提交
5118 5119 5120 5121 5122 5123 5124 5125 5126 5127 5128 5129 5130 5131 5132 5133 5134 5135
	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;
	}

5136
	err = ipc_has_perm(&msq->q_perm, perms);
L
Linus Torvalds 已提交
5137 5138 5139 5140 5141 5142 5143
	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;
5144
	struct common_audit_data ad;
5145
	u32 sid = current_sid();
L
Linus Torvalds 已提交
5146 5147 5148 5149 5150 5151 5152 5153 5154 5155 5156 5157 5158
	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
		 */
5159
		rc = security_transition_sid(sid, isec->sid, SECCLASS_MSG,
5160
					     NULL, &msec->sid);
L
Linus Torvalds 已提交
5161 5162 5163 5164
		if (rc)
			return rc;
	}

5165
	ad.type = LSM_AUDIT_DATA_IPC;
L
Linus Torvalds 已提交
5166 5167 5168
	ad.u.ipc_id = msq->q_perm.key;

	/* Can this process write to the queue? */
5169
	rc = avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
L
Linus Torvalds 已提交
5170 5171 5172
			  MSGQ__WRITE, &ad);
	if (!rc)
		/* Can this process send the message */
5173 5174
		rc = avc_has_perm(sid, msec->sid, SECCLASS_MSG,
				  MSG__SEND, &ad);
L
Linus Torvalds 已提交
5175 5176
	if (!rc)
		/* Can the message be put in the queue? */
5177 5178
		rc = avc_has_perm(msec->sid, isec->sid, SECCLASS_MSGQ,
				  MSGQ__ENQUEUE, &ad);
L
Linus Torvalds 已提交
5179 5180 5181 5182 5183 5184 5185 5186 5187 5188

	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;
5189
	struct common_audit_data ad;
5190
	u32 sid = task_sid(target);
L
Linus Torvalds 已提交
5191 5192 5193 5194 5195
	int rc;

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

5196
	ad.type = LSM_AUDIT_DATA_IPC;
5197
	ad.u.ipc_id = msq->q_perm.key;
L
Linus Torvalds 已提交
5198

5199
	rc = avc_has_perm(sid, isec->sid,
L
Linus Torvalds 已提交
5200 5201
			  SECCLASS_MSGQ, MSGQ__READ, &ad);
	if (!rc)
5202
		rc = avc_has_perm(sid, msec->sid,
L
Linus Torvalds 已提交
5203 5204 5205 5206 5207 5208 5209 5210
				  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;
5211
	struct common_audit_data ad;
5212
	u32 sid = current_sid();
L
Linus Torvalds 已提交
5213 5214 5215 5216 5217 5218 5219 5220
	int rc;

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

	isec = shp->shm_perm.security;

5221
	ad.type = LSM_AUDIT_DATA_IPC;
5222
	ad.u.ipc_id = shp->shm_perm.key;
L
Linus Torvalds 已提交
5223

5224
	rc = avc_has_perm(sid, isec->sid, SECCLASS_SHM,
L
Linus Torvalds 已提交
5225 5226 5227 5228 5229 5230 5231 5232 5233 5234 5235 5236 5237 5238 5239 5240
			  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;
5241
	struct common_audit_data ad;
5242
	u32 sid = current_sid();
L
Linus Torvalds 已提交
5243 5244 5245

	isec = shp->shm_perm.security;

5246
	ad.type = LSM_AUDIT_DATA_IPC;
L
Linus Torvalds 已提交
5247 5248
	ad.u.ipc_id = shp->shm_perm.key;

5249
	return avc_has_perm(sid, isec->sid, SECCLASS_SHM,
L
Linus Torvalds 已提交
5250 5251 5252 5253 5254 5255 5256 5257 5258
			    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;

5259
	switch (cmd) {
L
Linus Torvalds 已提交
5260 5261 5262 5263 5264 5265 5266 5267 5268 5269 5270 5271 5272 5273 5274 5275 5276 5277 5278 5279 5280 5281
	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;
	}

5282
	err = ipc_has_perm(&shp->shm_perm, perms);
L
Linus Torvalds 已提交
5283 5284 5285 5286 5287 5288 5289 5290 5291 5292 5293 5294 5295
	return err;
}

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

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

5296
	return ipc_has_perm(&shp->shm_perm, perms);
L
Linus Torvalds 已提交
5297 5298 5299 5300 5301 5302
}

/* Semaphore security operations */
static int selinux_sem_alloc_security(struct sem_array *sma)
{
	struct ipc_security_struct *isec;
5303
	struct common_audit_data ad;
5304
	u32 sid = current_sid();
L
Linus Torvalds 已提交
5305 5306 5307 5308 5309 5310 5311 5312
	int rc;

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

	isec = sma->sem_perm.security;

5313
	ad.type = LSM_AUDIT_DATA_IPC;
5314
	ad.u.ipc_id = sma->sem_perm.key;
L
Linus Torvalds 已提交
5315

5316
	rc = avc_has_perm(sid, isec->sid, SECCLASS_SEM,
L
Linus Torvalds 已提交
5317 5318 5319 5320 5321 5322 5323 5324 5325 5326 5327 5328 5329 5330 5331 5332
			  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;
5333
	struct common_audit_data ad;
5334
	u32 sid = current_sid();
L
Linus Torvalds 已提交
5335 5336 5337

	isec = sma->sem_perm.security;

5338
	ad.type = LSM_AUDIT_DATA_IPC;
L
Linus Torvalds 已提交
5339 5340
	ad.u.ipc_id = sma->sem_perm.key;

5341
	return avc_has_perm(sid, isec->sid, SECCLASS_SEM,
L
Linus Torvalds 已提交
5342 5343 5344 5345 5346 5347 5348 5349 5350
			    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;

5351
	switch (cmd) {
L
Linus Torvalds 已提交
5352 5353 5354 5355 5356 5357 5358 5359 5360 5361 5362 5363 5364 5365 5366 5367 5368 5369 5370 5371 5372 5373 5374 5375 5376 5377 5378 5379 5380 5381 5382
	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;
	}

5383
	err = ipc_has_perm(&sma->sem_perm, perms);
L
Linus Torvalds 已提交
5384 5385 5386 5387 5388 5389 5390 5391 5392 5393 5394 5395 5396
	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;

5397
	return ipc_has_perm(&sma->sem_perm, perms);
L
Linus Torvalds 已提交
5398 5399 5400 5401 5402 5403 5404 5405 5406 5407 5408 5409 5410 5411 5412
}

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;

5413
	return ipc_has_perm(ipcp, av);
L
Linus Torvalds 已提交
5414 5415
}

5416 5417 5418 5419 5420 5421
static void selinux_ipc_getsecid(struct kern_ipc_perm *ipcp, u32 *secid)
{
	struct ipc_security_struct *isec = ipcp->security;
	*secid = isec->sid;
}

5422
static void selinux_d_instantiate(struct dentry *dentry, struct inode *inode)
L
Linus Torvalds 已提交
5423 5424 5425 5426 5427 5428
{
	if (inode)
		inode_doinit_with_dentry(inode, dentry);
}

static int selinux_getprocattr(struct task_struct *p,
5429
			       char *name, char **value)
L
Linus Torvalds 已提交
5430
{
5431
	const struct task_security_struct *__tsec;
5432
	u32 sid;
L
Linus Torvalds 已提交
5433
	int error;
5434
	unsigned len;
L
Linus Torvalds 已提交
5435 5436

	if (current != p) {
5437
		error = current_has_perm(p, PROCESS__GETATTR);
L
Linus Torvalds 已提交
5438 5439 5440 5441
		if (error)
			return error;
	}

5442 5443
	rcu_read_lock();
	__tsec = __task_cred(p)->security;
L
Linus Torvalds 已提交
5444 5445

	if (!strcmp(name, "current"))
5446
		sid = __tsec->sid;
L
Linus Torvalds 已提交
5447
	else if (!strcmp(name, "prev"))
5448
		sid = __tsec->osid;
L
Linus Torvalds 已提交
5449
	else if (!strcmp(name, "exec"))
5450
		sid = __tsec->exec_sid;
L
Linus Torvalds 已提交
5451
	else if (!strcmp(name, "fscreate"))
5452
		sid = __tsec->create_sid;
5453
	else if (!strcmp(name, "keycreate"))
5454
		sid = __tsec->keycreate_sid;
5455
	else if (!strcmp(name, "sockcreate"))
5456
		sid = __tsec->sockcreate_sid;
L
Linus Torvalds 已提交
5457
	else
5458 5459
		goto invalid;
	rcu_read_unlock();
L
Linus Torvalds 已提交
5460 5461 5462 5463

	if (!sid)
		return 0;

5464 5465 5466 5467
	error = security_sid_to_context(sid, value, &len);
	if (error)
		return error;
	return len;
5468 5469 5470 5471

invalid:
	rcu_read_unlock();
	return -EINVAL;
L
Linus Torvalds 已提交
5472 5473 5474 5475 5476 5477
}

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
5478
	struct task_struct *tracer;
D
David Howells 已提交
5479 5480
	struct cred *new;
	u32 sid = 0, ptsid;
L
Linus Torvalds 已提交
5481 5482 5483 5484 5485 5486 5487 5488 5489 5490 5491 5492 5493 5494 5495
	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"))
5496
		error = current_has_perm(p, PROCESS__SETEXEC);
L
Linus Torvalds 已提交
5497
	else if (!strcmp(name, "fscreate"))
5498
		error = current_has_perm(p, PROCESS__SETFSCREATE);
5499
	else if (!strcmp(name, "keycreate"))
5500
		error = current_has_perm(p, PROCESS__SETKEYCREATE);
5501
	else if (!strcmp(name, "sockcreate"))
5502
		error = current_has_perm(p, PROCESS__SETSOCKCREATE);
L
Linus Torvalds 已提交
5503
	else if (!strcmp(name, "current"))
5504
		error = current_has_perm(p, PROCESS__SETCURRENT);
L
Linus Torvalds 已提交
5505 5506 5507 5508 5509 5510 5511 5512 5513 5514 5515 5516
	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);
5517
		if (error == -EINVAL && !strcmp(name, "fscreate")) {
5518 5519 5520 5521 5522 5523 5524 5525 5526 5527 5528 5529 5530 5531 5532
			if (!capable(CAP_MAC_ADMIN)) {
				struct audit_buffer *ab;
				size_t audit_size;

				/* We strip a nul only if it is at the end, otherwise the
				 * context contains a nul and we should audit that */
				if (str[size - 1] == '\0')
					audit_size = size - 1;
				else
					audit_size = size;
				ab = audit_log_start(current->audit_context, GFP_ATOMIC, AUDIT_SELINUX_ERR);
				audit_log_format(ab, "op=fscreate invalid_context=");
				audit_log_n_untrustedstring(ab, value, audit_size);
				audit_log_end(ab);

5533
				return error;
5534
			}
5535 5536 5537
			error = security_context_to_sid_force(value, size,
							      &sid);
		}
L
Linus Torvalds 已提交
5538 5539 5540 5541
		if (error)
			return error;
	}

D
David Howells 已提交
5542 5543 5544 5545
	new = prepare_creds();
	if (!new)
		return -ENOMEM;

L
Linus Torvalds 已提交
5546 5547 5548
	/* 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
5549
	   operation.  See selinux_bprm_set_creds for the execve
L
Linus Torvalds 已提交
5550 5551
	   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
5552 5553
	tsec = new->security;
	if (!strcmp(name, "exec")) {
L
Linus Torvalds 已提交
5554
		tsec->exec_sid = sid;
D
David Howells 已提交
5555
	} else if (!strcmp(name, "fscreate")) {
L
Linus Torvalds 已提交
5556
		tsec->create_sid = sid;
D
David Howells 已提交
5557
	} else if (!strcmp(name, "keycreate")) {
5558 5559
		error = may_create_key(sid, p);
		if (error)
D
David Howells 已提交
5560
			goto abort_change;
5561
		tsec->keycreate_sid = sid;
D
David Howells 已提交
5562
	} else if (!strcmp(name, "sockcreate")) {
5563
		tsec->sockcreate_sid = sid;
D
David Howells 已提交
5564 5565
	} else if (!strcmp(name, "current")) {
		error = -EINVAL;
L
Linus Torvalds 已提交
5566
		if (sid == 0)
D
David Howells 已提交
5567 5568 5569 5570
			goto abort_change;

		/* Only allow single threaded processes to change context */
		error = -EPERM;
5571
		if (!current_is_single_threaded()) {
D
David Howells 已提交
5572 5573 5574
			error = security_bounded_transition(tsec->sid, sid);
			if (error)
				goto abort_change;
5575
		}
L
Linus Torvalds 已提交
5576 5577 5578

		/* Check permissions for the transition. */
		error = avc_has_perm(tsec->sid, sid, SECCLASS_PROCESS,
5579
				     PROCESS__DYNTRANSITION, NULL);
L
Linus Torvalds 已提交
5580
		if (error)
D
David Howells 已提交
5581
			goto abort_change;
L
Linus Torvalds 已提交
5582 5583 5584

		/* Check for ptracing, and update the task SID if ok.
		   Otherwise, leave SID unchanged and fail. */
D
David Howells 已提交
5585
		ptsid = 0;
5586
		rcu_read_lock();
5587
		tracer = ptrace_parent(p);
D
David Howells 已提交
5588 5589
		if (tracer)
			ptsid = task_sid(tracer);
5590
		rcu_read_unlock();
D
David Howells 已提交
5591 5592 5593 5594

		if (tracer) {
			error = avc_has_perm(ptsid, sid, SECCLASS_PROCESS,
					     PROCESS__PTRACE, NULL);
L
Linus Torvalds 已提交
5595
			if (error)
D
David Howells 已提交
5596
				goto abort_change;
L
Linus Torvalds 已提交
5597 5598
		}

D
David Howells 已提交
5599 5600 5601 5602 5603 5604 5605
		tsec->sid = sid;
	} else {
		error = -EINVAL;
		goto abort_change;
	}

	commit_creds(new);
L
Linus Torvalds 已提交
5606
	return size;
D
David Howells 已提交
5607 5608 5609 5610

abort_change:
	abort_creds(new);
	return error;
L
Linus Torvalds 已提交
5611 5612
}

5613 5614 5615 5616 5617
static int selinux_ismaclabel(const char *name)
{
	return (strcmp(name, XATTR_SELINUX_SUFFIX) == 0);
}

5618 5619 5620 5621 5622
static int selinux_secid_to_secctx(u32 secid, char **secdata, u32 *seclen)
{
	return security_sid_to_context(secid, secdata, seclen);
}

5623
static int selinux_secctx_to_secid(const char *secdata, u32 seclen, u32 *secid)
5624 5625 5626 5627
{
	return security_context_to_sid(secdata, seclen, secid);
}

5628 5629
static void selinux_release_secctx(char *secdata, u32 seclen)
{
5630
	kfree(secdata);
5631 5632
}

5633 5634 5635 5636 5637 5638 5639 5640 5641 5642 5643 5644 5645 5646 5647 5648 5649 5650 5651 5652 5653 5654 5655 5656 5657 5658
/*
 *	called with inode->i_mutex locked
 */
static int selinux_inode_notifysecctx(struct inode *inode, void *ctx, u32 ctxlen)
{
	return selinux_inode_setsecurity(inode, XATTR_SELINUX_SUFFIX, ctx, ctxlen, 0);
}

/*
 *	called with inode->i_mutex locked
 */
static int selinux_inode_setsecctx(struct dentry *dentry, void *ctx, u32 ctxlen)
{
	return __vfs_setxattr_noperm(dentry, XATTR_NAME_SELINUX, ctx, ctxlen, 0);
}

static int selinux_inode_getsecctx(struct inode *inode, void **ctx, u32 *ctxlen)
{
	int len = 0;
	len = selinux_inode_getsecurity(inode, XATTR_SELINUX_SUFFIX,
						ctx, true);
	if (len < 0)
		return len;
	*ctxlen = len;
	return 0;
}
5659 5660
#ifdef CONFIG_KEYS

D
David Howells 已提交
5661
static int selinux_key_alloc(struct key *k, const struct cred *cred,
5662
			     unsigned long flags)
5663
{
D
David Howells 已提交
5664
	const struct task_security_struct *tsec;
5665 5666 5667 5668 5669 5670
	struct key_security_struct *ksec;

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

D
David Howells 已提交
5671 5672 5673
	tsec = cred->security;
	if (tsec->keycreate_sid)
		ksec->sid = tsec->keycreate_sid;
5674
	else
D
David Howells 已提交
5675
		ksec->sid = tsec->sid;
5676

5677
	k->security = ksec;
5678 5679 5680 5681 5682 5683 5684 5685 5686 5687 5688 5689
	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
5690 5691
				  const struct cred *cred,
				  key_perm_t perm)
5692 5693 5694
{
	struct key *key;
	struct key_security_struct *ksec;
5695
	u32 sid;
5696 5697 5698 5699 5700 5701 5702

	/* 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
5703
	sid = cred_sid(cred);
5704 5705 5706 5707 5708

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

	return avc_has_perm(sid, ksec->sid, SECCLASS_KEY, perm, NULL);
5709 5710
}

5711 5712 5713 5714 5715 5716 5717 5718 5719 5720 5721 5722 5723 5724
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;
}

5725 5726
#endif

L
Linus Torvalds 已提交
5727
static struct security_operations selinux_ops = {
5728 5729
	.name =				"selinux",

5730
	.ptrace_access_check =		selinux_ptrace_access_check,
5731
	.ptrace_traceme =		selinux_ptrace_traceme,
L
Linus Torvalds 已提交
5732
	.capget =			selinux_capget,
D
David Howells 已提交
5733
	.capset =			selinux_capset,
L
Linus Torvalds 已提交
5734 5735 5736 5737 5738 5739 5740 5741
	.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,

5742 5743 5744
	.bprm_set_creds =		selinux_bprm_set_creds,
	.bprm_committing_creds =	selinux_bprm_committing_creds,
	.bprm_committed_creds =		selinux_bprm_committed_creds,
L
Linus Torvalds 已提交
5745 5746 5747 5748 5749
	.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,
5750
	.sb_remount =			selinux_sb_remount,
5751
	.sb_kern_mount =		selinux_sb_kern_mount,
5752
	.sb_show_options =		selinux_sb_show_options,
L
Linus Torvalds 已提交
5753 5754 5755
	.sb_statfs =			selinux_sb_statfs,
	.sb_mount =			selinux_mount,
	.sb_umount =			selinux_umount,
5756
	.sb_set_mnt_opts =		selinux_set_mnt_opts,
5757
	.sb_clone_mnt_opts =		selinux_sb_clone_mnt_opts,
5758 5759
	.sb_parse_opts_str = 		selinux_parse_opts_str,

5760
	.dentry_init_security =		selinux_dentry_init_security,
L
Linus Torvalds 已提交
5761 5762 5763

	.inode_alloc_security =		selinux_inode_alloc_security,
	.inode_free_security =		selinux_inode_free_security,
5764
	.inode_init_security =		selinux_inode_init_security,
L
Linus Torvalds 已提交
5765 5766 5767 5768 5769 5770 5771 5772 5773 5774 5775 5776 5777 5778 5779 5780 5781 5782
	.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,
5783 5784 5785
	.inode_getsecurity =		selinux_inode_getsecurity,
	.inode_setsecurity =		selinux_inode_setsecurity,
	.inode_listsecurity =		selinux_inode_listsecurity,
5786
	.inode_getsecid =		selinux_inode_getsecid,
L
Linus Torvalds 已提交
5787 5788 5789 5790 5791

	.file_permission =		selinux_file_permission,
	.file_alloc_security =		selinux_file_alloc_security,
	.file_free_security =		selinux_file_free_security,
	.file_ioctl =			selinux_file_ioctl,
5792 5793
	.mmap_file =			selinux_mmap_file,
	.mmap_addr =			selinux_mmap_addr,
L
Linus Torvalds 已提交
5794 5795 5796 5797 5798 5799 5800
	.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,

5801
	.file_open =			selinux_file_open,
5802

L
Linus Torvalds 已提交
5803
	.task_create =			selinux_task_create,
5804
	.cred_alloc_blank =		selinux_cred_alloc_blank,
5805
	.cred_free =			selinux_cred_free,
D
David Howells 已提交
5806
	.cred_prepare =			selinux_cred_prepare,
5807
	.cred_transfer =		selinux_cred_transfer,
5808 5809
	.kernel_act_as =		selinux_kernel_act_as,
	.kernel_create_files_as =	selinux_kernel_create_files_as,
5810
	.kernel_module_request =	selinux_kernel_module_request,
L
Linus Torvalds 已提交
5811 5812
	.task_setpgid =			selinux_task_setpgid,
	.task_getpgid =			selinux_task_getpgid,
5813
	.task_getsid =			selinux_task_getsid,
5814
	.task_getsecid =		selinux_task_getsecid,
L
Linus Torvalds 已提交
5815
	.task_setnice =			selinux_task_setnice,
5816
	.task_setioprio =		selinux_task_setioprio,
5817
	.task_getioprio =		selinux_task_getioprio,
L
Linus Torvalds 已提交
5818 5819 5820
	.task_setrlimit =		selinux_task_setrlimit,
	.task_setscheduler =		selinux_task_setscheduler,
	.task_getscheduler =		selinux_task_getscheduler,
5821
	.task_movememory =		selinux_task_movememory,
L
Linus Torvalds 已提交
5822 5823
	.task_kill =			selinux_task_kill,
	.task_wait =			selinux_task_wait,
5824
	.task_to_inode =		selinux_task_to_inode,
L
Linus Torvalds 已提交
5825 5826

	.ipc_permission =		selinux_ipc_permission,
5827
	.ipc_getsecid =			selinux_ipc_getsecid,
L
Linus Torvalds 已提交
5828 5829 5830 5831 5832 5833 5834 5835 5836 5837 5838 5839 5840 5841 5842 5843 5844

	.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,

5845 5846
	.sem_alloc_security =		selinux_sem_alloc_security,
	.sem_free_security =		selinux_sem_free_security,
L
Linus Torvalds 已提交
5847 5848 5849 5850
	.sem_associate =		selinux_sem_associate,
	.sem_semctl =			selinux_sem_semctl,
	.sem_semop =			selinux_sem_semop,

5851
	.d_instantiate =		selinux_d_instantiate,
L
Linus Torvalds 已提交
5852

5853 5854
	.getprocattr =			selinux_getprocattr,
	.setprocattr =			selinux_setprocattr,
L
Linus Torvalds 已提交
5855

5856
	.ismaclabel =			selinux_ismaclabel,
5857
	.secid_to_secctx =		selinux_secid_to_secctx,
5858
	.secctx_to_secid =		selinux_secctx_to_secid,
5859
	.release_secctx =		selinux_release_secctx,
5860 5861 5862
	.inode_notifysecctx =		selinux_inode_notifysecctx,
	.inode_setsecctx =		selinux_inode_setsecctx,
	.inode_getsecctx =		selinux_inode_getsecctx,
5863

5864
	.unix_stream_connect =		selinux_socket_unix_stream_connect,
L
Linus Torvalds 已提交
5865 5866 5867 5868 5869 5870 5871 5872 5873 5874 5875 5876 5877 5878 5879 5880
	.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
5881 5882
	.socket_getpeersec_stream =	selinux_socket_getpeersec_stream,
	.socket_getpeersec_dgram =	selinux_socket_getpeersec_dgram,
L
Linus Torvalds 已提交
5883 5884
	.sk_alloc_security =		selinux_sk_alloc_security,
	.sk_free_security =		selinux_sk_free_security,
5885
	.sk_clone_security =		selinux_sk_clone_security,
5886
	.sk_getsecid =			selinux_sk_getsecid,
5887 5888 5889
	.sock_graft =			selinux_sock_graft,
	.inet_conn_request =		selinux_inet_conn_request,
	.inet_csk_clone =		selinux_inet_csk_clone,
5890
	.inet_conn_established =	selinux_inet_conn_established,
5891 5892 5893
	.secmark_relabel_packet =	selinux_secmark_relabel_packet,
	.secmark_refcount_inc =		selinux_secmark_refcount_inc,
	.secmark_refcount_dec =		selinux_secmark_refcount_dec,
5894
	.req_classify_flow =		selinux_req_classify_flow,
5895 5896
	.tun_dev_alloc_security =	selinux_tun_dev_alloc_security,
	.tun_dev_free_security =	selinux_tun_dev_free_security,
5897
	.tun_dev_create =		selinux_tun_dev_create,
5898
	.tun_dev_attach_queue =		selinux_tun_dev_attach_queue,
5899
	.tun_dev_attach =		selinux_tun_dev_attach,
5900
	.tun_dev_open =			selinux_tun_dev_open,
5901
	.skb_owned_by =			selinux_skb_owned_by,
5902 5903 5904 5905 5906

#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
5907
	.xfrm_policy_delete_security =	selinux_xfrm_policy_delete,
5908 5909
	.xfrm_state_alloc =		selinux_xfrm_state_alloc,
	.xfrm_state_alloc_acquire =	selinux_xfrm_state_alloc_acquire,
5910
	.xfrm_state_free_security =	selinux_xfrm_state_free,
C
Catherine Zhang 已提交
5911
	.xfrm_state_delete_security =	selinux_xfrm_state_delete,
5912
	.xfrm_policy_lookup =		selinux_xfrm_policy_lookup,
5913 5914
	.xfrm_state_pol_flow_match =	selinux_xfrm_state_pol_flow_match,
	.xfrm_decode_session =		selinux_xfrm_decode_session,
L
Linus Torvalds 已提交
5915
#endif
5916 5917

#ifdef CONFIG_KEYS
5918 5919 5920
	.key_alloc =			selinux_key_alloc,
	.key_free =			selinux_key_free,
	.key_permission =		selinux_key_permission,
5921
	.key_getsecurity =		selinux_key_getsecurity,
5922
#endif
5923 5924 5925 5926 5927 5928 5929

#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
5930 5931 5932 5933
};

static __init int selinux_init(void)
{
5934 5935 5936 5937 5938
	if (!security_module_enable(&selinux_ops)) {
		selinux_enabled = 0;
		return 0;
	}

L
Linus Torvalds 已提交
5939 5940 5941 5942 5943 5944 5945 5946
	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
5947
	cred_init_security();
L
Linus Torvalds 已提交
5948

5949 5950
	default_noexec = !(VM_DATA_DEFAULT_FLAGS & VM_EXEC);

5951 5952
	sel_inode_cache = kmem_cache_create("selinux_inode_security",
					    sizeof(struct inode_security_struct),
5953
					    0, SLAB_PANIC, NULL);
L
Linus Torvalds 已提交
5954 5955
	avc_init();

5956
	if (register_security(&selinux_ops))
L
Linus Torvalds 已提交
5957 5958
		panic("SELinux: Unable to register with kernel.\n");

5959
	if (selinux_enforcing)
5960
		printk(KERN_DEBUG "SELinux:  Starting in enforcing mode\n");
5961
	else
5962
		printk(KERN_DEBUG "SELinux:  Starting in permissive mode\n");
5963

L
Linus Torvalds 已提交
5964 5965 5966
	return 0;
}

5967 5968 5969 5970 5971
static void delayed_superblock_init(struct super_block *sb, void *unused)
{
	superblock_doinit(sb, NULL);
}

L
Linus Torvalds 已提交
5972 5973
void selinux_complete_init(void)
{
5974
	printk(KERN_DEBUG "SELinux:  Completing initialization.\n");
L
Linus Torvalds 已提交
5975 5976

	/* Set up any superblocks initialized prior to the policy load. */
5977
	printk(KERN_DEBUG "SELinux:  Setting up existing superblocks.\n");
5978
	iterate_supers(delayed_superblock_init, NULL);
L
Linus Torvalds 已提交
5979 5980 5981 5982 5983 5984
}

/* SELinux requires early initialization in order to label
   all processes and objects when they are created. */
security_initcall(selinux_init);

5985
#if defined(CONFIG_NETFILTER)
L
Linus Torvalds 已提交
5986

5987 5988 5989 5990
static struct nf_hook_ops selinux_ipv4_ops[] = {
	{
		.hook =		selinux_ipv4_postroute,
		.owner =	THIS_MODULE,
5991
		.pf =		NFPROTO_IPV4,
5992 5993 5994 5995 5996 5997
		.hooknum =	NF_INET_POST_ROUTING,
		.priority =	NF_IP_PRI_SELINUX_LAST,
	},
	{
		.hook =		selinux_ipv4_forward,
		.owner =	THIS_MODULE,
5998
		.pf =		NFPROTO_IPV4,
5999 6000
		.hooknum =	NF_INET_FORWARD,
		.priority =	NF_IP_PRI_SELINUX_FIRST,
6001 6002 6003 6004
	},
	{
		.hook =		selinux_ipv4_output,
		.owner =	THIS_MODULE,
6005
		.pf =		NFPROTO_IPV4,
6006 6007
		.hooknum =	NF_INET_LOCAL_OUT,
		.priority =	NF_IP_PRI_SELINUX_FIRST,
6008
	}
L
Linus Torvalds 已提交
6009 6010 6011 6012
};

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

6013 6014 6015 6016
static struct nf_hook_ops selinux_ipv6_ops[] = {
	{
		.hook =		selinux_ipv6_postroute,
		.owner =	THIS_MODULE,
6017
		.pf =		NFPROTO_IPV6,
6018 6019 6020 6021 6022 6023
		.hooknum =	NF_INET_POST_ROUTING,
		.priority =	NF_IP6_PRI_SELINUX_LAST,
	},
	{
		.hook =		selinux_ipv6_forward,
		.owner =	THIS_MODULE,
6024
		.pf =		NFPROTO_IPV6,
6025 6026 6027
		.hooknum =	NF_INET_FORWARD,
		.priority =	NF_IP6_PRI_SELINUX_FIRST,
	}
L
Linus Torvalds 已提交
6028 6029 6030 6031 6032 6033 6034 6035 6036 6037
};

#endif	/* IPV6 */

static int __init selinux_nf_ip_init(void)
{
	int err = 0;

	if (!selinux_enabled)
		goto out;
6038 6039 6040

	printk(KERN_DEBUG "SELinux:  Registering netfilter hooks\n");

6041 6042 6043
	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
6044 6045

#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
6046 6047 6048
	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
6049
#endif	/* IPV6 */
6050

L
Linus Torvalds 已提交
6051 6052 6053 6054 6055 6056 6057 6058 6059
out:
	return err;
}

__initcall(selinux_nf_ip_init);

#ifdef CONFIG_SECURITY_SELINUX_DISABLE
static void selinux_nf_ip_exit(void)
{
6060
	printk(KERN_DEBUG "SELinux:  Unregistering netfilter hooks\n");
L
Linus Torvalds 已提交
6061

6062
	nf_unregister_hooks(selinux_ipv4_ops, ARRAY_SIZE(selinux_ipv4_ops));
L
Linus Torvalds 已提交
6063
#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
6064
	nf_unregister_hooks(selinux_ipv6_ops, ARRAY_SIZE(selinux_ipv6_ops));
L
Linus Torvalds 已提交
6065 6066 6067 6068
#endif	/* IPV6 */
}
#endif

6069
#else /* CONFIG_NETFILTER */
L
Linus Torvalds 已提交
6070 6071 6072 6073 6074

#ifdef CONFIG_SECURITY_SELINUX_DISABLE
#define selinux_nf_ip_exit()
#endif

6075
#endif /* CONFIG_NETFILTER */
L
Linus Torvalds 已提交
6076 6077

#ifdef CONFIG_SECURITY_SELINUX_DISABLE
6078 6079
static int selinux_disabled;

L
Linus Torvalds 已提交
6080 6081 6082 6083 6084 6085 6086 6087 6088 6089 6090 6091 6092 6093 6094
int selinux_disable(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;
6095
	selinux_enabled = 0;
L
Linus Torvalds 已提交
6096

6097
	reset_security_ops();
L
Linus Torvalds 已提交
6098

6099 6100 6101
	/* Try to destroy the avc node cache */
	avc_disable();

L
Linus Torvalds 已提交
6102 6103 6104 6105 6106 6107 6108 6109 6110
	/* Unregister netfilter hooks. */
	selinux_nf_ip_exit();

	/* Unregister selinuxfs. */
	exit_sel_fs();

	return 0;
}
#endif