hooks.c 141.1 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
#include <linux/errno.h>
31
#include <linux/ext2_fs.h>
L
Linus Torvalds 已提交
32 33 34 35 36 37 38 39 40
#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>
41
#include <linux/proc_fs.h>
L
Linus Torvalds 已提交
42 43 44
#include <linux/swap.h>
#include <linux/spinlock.h>
#include <linux/syscalls.h>
45
#include <linux/dcache.h>
L
Linus Torvalds 已提交
46
#include <linux/file.h>
A
Al Viro 已提交
47
#include <linux/fdtable.h>
L
Linus Torvalds 已提交
48 49 50 51 52 53
#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>
54
#include <net/ip.h>		/* for local_port_range[] */
L
Linus Torvalds 已提交
55
#include <net/tcp.h>		/* struct or_callable used in sock_rcv_skb */
56
#include <net/net_namespace.h>
57
#include <net/netlabel.h>
58
#include <linux/uaccess.h>
L
Linus Torvalds 已提交
59
#include <asm/ioctls.h>
A
Arun Sharma 已提交
60
#include <linux/atomic.h>
L
Linus Torvalds 已提交
61 62 63 64 65 66
#include <linux/bitops.h>
#include <linux/interrupt.h>
#include <linux/netdevice.h>	/* for network interface checks */
#include <linux/netlink.h>
#include <linux/tcp.h>
#include <linux/udp.h>
J
James Morris 已提交
67
#include <linux/dccp.h>
L
Linus Torvalds 已提交
68 69 70 71 72 73 74 75 76
#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>
77
#include <linux/string.h>
C
Catherine Zhang 已提交
78
#include <linux/selinux.h>
79
#include <linux/mutex.h>
80
#include <linux/posix-timers.h>
81
#include <linux/syslog.h>
82
#include <linux/user_namespace.h>
83
#include <linux/export.h>
L
Linus Torvalds 已提交
84 85 86 87

#include "avc.h"
#include "objsec.h"
#include "netif.h"
88
#include "netnode.h"
P
Paul Moore 已提交
89
#include "netport.h"
90
#include "xfrm.h"
91
#include "netlabel.h"
92
#include "audit.h"
93
#include "avc_ss.h"
L
Linus Torvalds 已提交
94

95
#define NUM_SEL_MNT_OPTS 5
96

97
extern struct security_operations *security_ops;
L
Linus Torvalds 已提交
98

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

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

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

#ifdef CONFIG_SECURITY_SELINUX_BOOTPARAM
int selinux_enabled = CONFIG_SECURITY_SELINUX_BOOTPARAM_VALUE;

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

130
static struct kmem_cache *sel_inode_cache;
131

132 133 134 135 136 137 138 139 140 141 142 143 144 145 146
/**
 * selinux_secmark_enabled - Check to see if SECMARK is currently enabled
 *
 * Description:
 * This function checks the SECMARK reference counter to see if any SECMARK
 * targets are currently configured, if the reference counter is greater than
 * zero SECMARK is considered to be enabled.  Returns true (1) if SECMARK is
 * enabled, false (0) if SECMARK is disabled.
 *
 */
static int selinux_secmark_enabled(void)
{
	return (atomic_read(&selinux_secmark_refcount) > 0);
}

D
David Howells 已提交
147 148 149 150
/*
 * initialise the security for the init task
 */
static void cred_init_security(void)
L
Linus Torvalds 已提交
151
{
152
	struct cred *cred = (struct cred *) current->real_cred;
L
Linus Torvalds 已提交
153 154
	struct task_security_struct *tsec;

J
James Morris 已提交
155
	tsec = kzalloc(sizeof(struct task_security_struct), GFP_KERNEL);
L
Linus Torvalds 已提交
156
	if (!tsec)
D
David Howells 已提交
157
		panic("SELinux:  Failed to initialize initial task.\n");
L
Linus Torvalds 已提交
158

D
David Howells 已提交
159
	tsec->osid = tsec->sid = SECINITSID_KERNEL;
160
	cred->security = tsec;
L
Linus Torvalds 已提交
161 162
}

163 164 165 166 167 168 169 170 171 172 173
/*
 * 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;
}

174
/*
175
 * get the objective security ID of a task
176 177 178 179 180 181
 */
static inline u32 task_sid(const struct task_struct *task)
{
	u32 sid;

	rcu_read_lock();
182
	sid = cred_sid(__task_cred(task));
183 184 185 186 187
	rcu_read_unlock();
	return sid;
}

/*
188
 * get the subjective security ID of the current task
189 190 191
 */
static inline u32 current_sid(void)
{
192
	const struct task_security_struct *tsec = current_security();
193 194 195 196

	return tsec->sid;
}

197 198
/* Allocate and free functions for each kind of security blob. */

L
Linus Torvalds 已提交
199 200 201
static int inode_alloc_security(struct inode *inode)
{
	struct inode_security_struct *isec;
202
	u32 sid = current_sid();
L
Linus Torvalds 已提交
203

204
	isec = kmem_cache_zalloc(sel_inode_cache, GFP_NOFS);
L
Linus Torvalds 已提交
205 206 207
	if (!isec)
		return -ENOMEM;

208
	mutex_init(&isec->lock);
L
Linus Torvalds 已提交
209 210 211 212
	INIT_LIST_HEAD(&isec->list);
	isec->inode = inode;
	isec->sid = SECINITSID_UNLABELED;
	isec->sclass = SECCLASS_FILE;
213
	isec->task_sid = sid;
L
Linus Torvalds 已提交
214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229
	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;
230
	kmem_cache_free(sel_inode_cache, isec);
L
Linus Torvalds 已提交
231 232 233 234 235
}

static int file_alloc_security(struct file *file)
{
	struct file_security_struct *fsec;
236
	u32 sid = current_sid();
L
Linus Torvalds 已提交
237

238
	fsec = kzalloc(sizeof(struct file_security_struct), GFP_KERNEL);
L
Linus Torvalds 已提交
239 240 241
	if (!fsec)
		return -ENOMEM;

242 243
	fsec->sid = sid;
	fsec->fown_sid = sid;
L
Linus Torvalds 已提交
244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259
	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
260
	sbsec = kzalloc(sizeof(struct superblock_security_struct), GFP_KERNEL);
L
Linus Torvalds 已提交
261 262 263
	if (!sbsec)
		return -ENOMEM;

264
	mutex_init(&sbsec->lock);
L
Linus Torvalds 已提交
265 266 267 268 269
	INIT_LIST_HEAD(&sbsec->isec_head);
	spin_lock_init(&sbsec->isec_lock);
	sbsec->sb = sb;
	sbsec->sid = SECINITSID_UNLABELED;
	sbsec->def_sid = SECINITSID_FILE;
270
	sbsec->mntpoint_sid = SECINITSID_UNLABELED;
L
Linus Torvalds 已提交
271 272 273 274 275 276 277 278 279 280 281 282 283 284
	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. */

285
static const char *labeling_behaviors[6] = {
L
Linus Torvalds 已提交
286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301
	"uses xattr",
	"uses transition SIDs",
	"uses task SIDs",
	"uses genfs_contexts",
	"not configured for labeling",
	"uses mountpoint labeling",
};

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

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

enum {
302
	Opt_error = -1,
L
Linus Torvalds 已提交
303 304
	Opt_context = 1,
	Opt_fscontext = 2,
305 306
	Opt_defcontext = 3,
	Opt_rootcontext = 4,
307
	Opt_labelsupport = 5,
L
Linus Torvalds 已提交
308 309
};

310
static const match_table_t tokens = {
311 312 313 314
	{Opt_context, CONTEXT_STR "%s"},
	{Opt_fscontext, FSCONTEXT_STR "%s"},
	{Opt_defcontext, DEFCONTEXT_STR "%s"},
	{Opt_rootcontext, ROOTCONTEXT_STR "%s"},
315
	{Opt_labelsupport, LABELSUPP_STR},
316
	{Opt_error, NULL},
L
Linus Torvalds 已提交
317 318 319 320
};

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

321 322
static int may_context_mount_sb_relabel(u32 sid,
			struct superblock_security_struct *sbsec,
323
			const struct cred *cred)
324
{
325
	const struct task_security_struct *tsec = cred->security;
326 327 328 329 330 331 332 333 334 335 336 337
	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;
}

338 339
static int may_context_mount_inode_relabel(u32 sid,
			struct superblock_security_struct *sbsec,
340
			const struct cred *cred)
341
{
342
	const struct task_security_struct *tsec = cred->security;
343 344 345 346 347 348 349 350 351 352 353
	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;
}

354
static int sb_finish_set_opts(struct super_block *sb)
L
Linus Torvalds 已提交
355 356
{
	struct superblock_security_struct *sbsec = sb->s_security;
357 358 359
	struct dentry *root = sb->s_root;
	struct inode *root_inode = root->d_inode;
	int rc = 0;
L
Linus Torvalds 已提交
360

361 362 363 364 365 366 367 368 369 370 371 372 373 374 375 376 377 378 379 380 381 382 383 384 385
	if (sbsec->behavior == SECURITY_FS_USE_XATTR) {
		/* Make sure that the xattr handler exists and that no
		   error other than -ENODATA is returned by getxattr on
		   the root directory.  -ENODATA is ok, as this may be
		   the first boot of the SELinux kernel before we have
		   assigned xattr values to the filesystem. */
		if (!root_inode->i_op->getxattr) {
			printk(KERN_WARNING "SELinux: (dev %s, type %s) has no "
			       "xattr support\n", sb->s_id, sb->s_type->name);
			rc = -EOPNOTSUPP;
			goto out;
		}
		rc = root_inode->i_op->getxattr(root, XATTR_NAME_SELINUX, NULL, 0);
		if (rc < 0 && rc != -ENODATA) {
			if (rc == -EOPNOTSUPP)
				printk(KERN_WARNING "SELinux: (dev %s, type "
				       "%s) has no security xattr handler\n",
				       sb->s_id, sb->s_type->name);
			else
				printk(KERN_WARNING "SELinux: (dev %s, type "
				       "%s) getxattr errno %d\n", sb->s_id,
				       sb->s_type->name, -rc);
			goto out;
		}
	}
L
Linus Torvalds 已提交
386

387
	sbsec->flags |= (SE_SBINITIALIZED | SE_SBLABELSUPP);
L
Linus Torvalds 已提交
388

389 390 391 392 393 394 395
	if (sbsec->behavior > ARRAY_SIZE(labeling_behaviors))
		printk(KERN_ERR "SELinux: initialized (dev %s, type %s), unknown behavior\n",
		       sb->s_id, sb->s_type->name);
	else
		printk(KERN_DEBUG "SELinux: initialized (dev %s, type %s), %s\n",
		       sb->s_id, sb->s_type->name,
		       labeling_behaviors[sbsec->behavior-1]);
L
Linus Torvalds 已提交
396

397 398 399 400 401 402
	if (sbsec->behavior == SECURITY_FS_USE_GENFS ||
	    sbsec->behavior == SECURITY_FS_USE_MNTPOINT ||
	    sbsec->behavior == SECURITY_FS_USE_NONE ||
	    sbsec->behavior > ARRAY_SIZE(labeling_behaviors))
		sbsec->flags &= ~SE_SBLABELSUPP;

403 404 405 406
	/* Special handling for sysfs. Is genfs but also has setxattr handler*/
	if (strncmp(sb->s_type->name, "sysfs", sizeof("sysfs")) == 0)
		sbsec->flags |= SE_SBLABELSUPP;

407 408
	/* Initialize the root inode. */
	rc = inode_doinit_with_dentry(root_inode, root);
L
Linus Torvalds 已提交
409

410 411 412 413 414 415 416 417 418 419 420 421 422 423 424 425 426 427 428 429 430 431 432 433 434 435
	/* 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
436

437 438 439 440 441 442
/*
 * 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,
443
				struct security_mnt_opts *opts)
444 445 446 447 448 449
{
	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
450

451
	security_init_mnt_opts(opts);
L
Linus Torvalds 已提交
452

453
	if (!(sbsec->flags & SE_SBINITIALIZED))
454
		return -EINVAL;
L
Linus Torvalds 已提交
455

456 457
	if (!ss_initialized)
		return -EINVAL;
L
Linus Torvalds 已提交
458

459
	tmp = sbsec->flags & SE_MNTMASK;
460 461 462
	/* count the number of mount options for this sb */
	for (i = 0; i < 8; i++) {
		if (tmp & 0x01)
463
			opts->num_mnt_opts++;
464 465
		tmp >>= 1;
	}
466 467 468
	/* Check if the Label support flag is set */
	if (sbsec->flags & SE_SBLABELSUPP)
		opts->num_mnt_opts++;
L
Linus Torvalds 已提交
469

470 471
	opts->mnt_opts = kcalloc(opts->num_mnt_opts, sizeof(char *), GFP_ATOMIC);
	if (!opts->mnt_opts) {
472 473 474
		rc = -ENOMEM;
		goto out_free;
	}
L
Linus Torvalds 已提交
475

476 477
	opts->mnt_opts_flags = kcalloc(opts->num_mnt_opts, sizeof(int), GFP_ATOMIC);
	if (!opts->mnt_opts_flags) {
478 479 480
		rc = -ENOMEM;
		goto out_free;
	}
L
Linus Torvalds 已提交
481

482 483 484 485 486
	i = 0;
	if (sbsec->flags & FSCONTEXT_MNT) {
		rc = security_sid_to_context(sbsec->sid, &context, &len);
		if (rc)
			goto out_free;
487 488
		opts->mnt_opts[i] = context;
		opts->mnt_opts_flags[i++] = FSCONTEXT_MNT;
489 490 491 492 493
	}
	if (sbsec->flags & CONTEXT_MNT) {
		rc = security_sid_to_context(sbsec->mntpoint_sid, &context, &len);
		if (rc)
			goto out_free;
494 495
		opts->mnt_opts[i] = context;
		opts->mnt_opts_flags[i++] = CONTEXT_MNT;
496 497 498 499 500
	}
	if (sbsec->flags & DEFCONTEXT_MNT) {
		rc = security_sid_to_context(sbsec->def_sid, &context, &len);
		if (rc)
			goto out_free;
501 502
		opts->mnt_opts[i] = context;
		opts->mnt_opts_flags[i++] = DEFCONTEXT_MNT;
503 504 505 506
	}
	if (sbsec->flags & ROOTCONTEXT_MNT) {
		struct inode *root = sbsec->sb->s_root->d_inode;
		struct inode_security_struct *isec = root->i_security;
507

508 509 510
		rc = security_sid_to_context(isec->sid, &context, &len);
		if (rc)
			goto out_free;
511 512
		opts->mnt_opts[i] = context;
		opts->mnt_opts_flags[i++] = ROOTCONTEXT_MNT;
513
	}
514 515 516 517
	if (sbsec->flags & SE_SBLABELSUPP) {
		opts->mnt_opts[i] = NULL;
		opts->mnt_opts_flags[i++] = SE_SBLABELSUPP;
	}
L
Linus Torvalds 已提交
518

519
	BUG_ON(i != opts->num_mnt_opts);
L
Linus Torvalds 已提交
520

521 522 523
	return 0;

out_free:
524
	security_free_mnt_opts(opts);
525 526
	return rc;
}
L
Linus Torvalds 已提交
527

528 529 530
static int bad_option(struct superblock_security_struct *sbsec, char flag,
		      u32 old_sid, u32 new_sid)
{
531 532
	char mnt_flags = sbsec->flags & SE_MNTMASK;

533
	/* check if the old mount command had the same options */
534
	if (sbsec->flags & SE_SBINITIALIZED)
535 536 537 538 539 540 541
		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
	 */
542 543
	if (!(sbsec->flags & SE_SBINITIALIZED))
		if (mnt_flags & flag)
544 545 546
			return 1;
	return 0;
}
547

548 549 550 551
/*
 * Allow filesystems with binary mount data to explicitly set mount point
 * labeling information.
 */
552 553
static int selinux_set_mnt_opts(struct super_block *sb,
				struct security_mnt_opts *opts)
554
{
555
	const struct cred *cred = current_cred();
556 557 558
	int rc = 0, i;
	struct superblock_security_struct *sbsec = sb->s_security;
	const char *name = sb->s_type->name;
559 560
	struct inode *inode = sbsec->sb->s_root->d_inode;
	struct inode_security_struct *root_isec = inode->i_security;
561 562
	u32 fscontext_sid = 0, context_sid = 0, rootcontext_sid = 0;
	u32 defcontext_sid = 0;
563 564 565
	char **mount_options = opts->mnt_opts;
	int *flags = opts->mnt_opts_flags;
	int num_opts = opts->num_mnt_opts;
566 567 568 569 570 571 572 573 574 575 576

	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
577 578
		printk(KERN_WARNING "SELinux: Unable to set superblock options "
			"before the security server is initialized\n");
L
Linus Torvalds 已提交
579
		goto out;
580
	}
L
Linus Torvalds 已提交
581

582 583 584 585 586 587 588 589 590 591 592
	/*
	 * 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)
	 */
593
	if ((sbsec->flags & SE_SBINITIALIZED) && (sb->s_type->fs_flags & FS_BINARY_MOUNTDATA)
594
	    && (num_opts == 0))
595
		goto out;
596

597 598 599 600 601 602 603
	/*
	 * 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;
604 605 606

		if (flags[i] == SE_SBLABELSUPP)
			continue;
607 608
		rc = security_context_to_sid(mount_options[i],
					     strlen(mount_options[i]), &sid);
L
Linus Torvalds 已提交
609 610 611
		if (rc) {
			printk(KERN_WARNING "SELinux: security_context_to_sid"
			       "(%s) failed for (dev %s, type %s) errno=%d\n",
612 613 614 615 616 617 618 619 620 621 622 623 624 625 626 627 628 629 630 631 632 633 634 635 636 637 638 639 640 641 642 643 644 645 646 647 648 649 650 651 652 653 654 655 656
			       mount_options[i], sb->s_id, name, rc);
			goto out;
		}
		switch (flags[i]) {
		case FSCONTEXT_MNT:
			fscontext_sid = sid;

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

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

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

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

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

			sbsec->flags |= ROOTCONTEXT_MNT;

			break;
		case DEFCONTEXT_MNT:
			defcontext_sid = sid;

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

			sbsec->flags |= DEFCONTEXT_MNT;

			break;
		default:
			rc = -EINVAL;
			goto out;
L
Linus Torvalds 已提交
657
		}
658 659
	}

660
	if (sbsec->flags & SE_SBINITIALIZED) {
661
		/* previously mounted with options, but not on this attempt? */
662
		if ((sbsec->flags & SE_MNTMASK) && !num_opts)
663 664 665 666 667
			goto out_double_mount;
		rc = 0;
		goto out;
	}

668
	if (strcmp(sb->s_type->name, "proc") == 0)
669
		sbsec->flags |= SE_SBPROC;
670 671

	/* Determine the labeling behavior to use for this filesystem type. */
672
	rc = security_fs_use((sbsec->flags & SE_SBPROC) ? "proc" : sb->s_type->name, &sbsec->behavior, &sbsec->sid);
673 674
	if (rc) {
		printk(KERN_WARNING "%s: security_fs_use(%s) returned %d\n",
675
		       __func__, sb->s_type->name, rc);
676 677
		goto out;
	}
L
Linus Torvalds 已提交
678

679 680
	/* sets the context of the superblock for the fs being mounted. */
	if (fscontext_sid) {
681
		rc = may_context_mount_sb_relabel(fscontext_sid, sbsec, cred);
L
Linus Torvalds 已提交
682
		if (rc)
683
			goto out;
L
Linus Torvalds 已提交
684

685
		sbsec->sid = fscontext_sid;
686 687 688 689 690 691 692
	}

	/*
	 * 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.
	 */
693 694
	if (context_sid) {
		if (!fscontext_sid) {
695 696
			rc = may_context_mount_sb_relabel(context_sid, sbsec,
							  cred);
697
			if (rc)
698 699
				goto out;
			sbsec->sid = context_sid;
700
		} else {
701 702
			rc = may_context_mount_inode_relabel(context_sid, sbsec,
							     cred);
703
			if (rc)
704
				goto out;
705
		}
706 707
		if (!rootcontext_sid)
			rootcontext_sid = context_sid;
L
Linus Torvalds 已提交
708

709
		sbsec->mntpoint_sid = context_sid;
710
		sbsec->behavior = SECURITY_FS_USE_MNTPOINT;
L
Linus Torvalds 已提交
711 712
	}

713
	if (rootcontext_sid) {
714 715
		rc = may_context_mount_inode_relabel(rootcontext_sid, sbsec,
						     cred);
716
		if (rc)
717
			goto out;
718

719 720
		root_isec->sid = rootcontext_sid;
		root_isec->initialized = 1;
721 722
	}

723 724 725 726 727 728
	if (defcontext_sid) {
		if (sbsec->behavior != SECURITY_FS_USE_XATTR) {
			rc = -EINVAL;
			printk(KERN_WARNING "SELinux: defcontext option is "
			       "invalid for this filesystem type\n");
			goto out;
L
Linus Torvalds 已提交
729 730
		}

731 732
		if (defcontext_sid != sbsec->def_sid) {
			rc = may_context_mount_inode_relabel(defcontext_sid,
733
							     sbsec, cred);
734 735 736
			if (rc)
				goto out;
		}
L
Linus Torvalds 已提交
737

738
		sbsec->def_sid = defcontext_sid;
L
Linus Torvalds 已提交
739 740
	}

741
	rc = sb_finish_set_opts(sb);
L
Linus Torvalds 已提交
742
out:
743
	mutex_unlock(&sbsec->lock);
L
Linus Torvalds 已提交
744
	return rc;
745 746 747 748 749
out_double_mount:
	rc = -EINVAL;
	printk(KERN_WARNING "SELinux: mount invalid.  Same superblock, different "
	       "security settings for (dev %s, type %s)\n", sb->s_id, name);
	goto out;
L
Linus Torvalds 已提交
750 751
}

752 753
static void selinux_sb_clone_mnt_opts(const struct super_block *oldsb,
					struct super_block *newsb)
L
Linus Torvalds 已提交
754
{
755 756
	const struct superblock_security_struct *oldsbsec = oldsb->s_security;
	struct superblock_security_struct *newsbsec = newsb->s_security;
L
Linus Torvalds 已提交
757

758 759 760
	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
761

762 763
	/*
	 * if the parent was able to be mounted it clearly had no special lsm
764
	 * mount options.  thus we can safely deal with this superblock later
765
	 */
766
	if (!ss_initialized)
767
		return;
768 769

	/* how can we clone if the old one wasn't set up?? */
770
	BUG_ON(!(oldsbsec->flags & SE_SBINITIALIZED));
771

772
	/* if fs is reusing a sb, just let its options stand... */
773
	if (newsbsec->flags & SE_SBINITIALIZED)
774 775
		return;

776 777 778 779 780 781 782 783 784 785 786 787 788 789 790 791 792 793 794
	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
795
	}
796 797 798 799 800
	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
801

802
		newisec->sid = oldisec->sid;
L
Linus Torvalds 已提交
803 804
	}

805 806 807 808
	sb_finish_set_opts(newsb);
	mutex_unlock(&newsbsec->lock);
}

809 810
static int selinux_parse_opts_str(char *options,
				  struct security_mnt_opts *opts)
811
{
812
	char *p;
813 814
	char *context = NULL, *defcontext = NULL;
	char *fscontext = NULL, *rootcontext = NULL;
815
	int rc, num_mnt_opts = 0;
L
Linus Torvalds 已提交
816

817
	opts->num_mnt_opts = 0;
L
Linus Torvalds 已提交
818

819 820 821 822
	/* Standard string-based options. */
	while ((p = strsep(&options, "|")) != NULL) {
		int token;
		substring_t args[MAX_OPT_ARGS];
L
Linus Torvalds 已提交
823

824 825
		if (!*p)
			continue;
L
Linus Torvalds 已提交
826

827
		token = match_token(p, tokens, args);
L
Linus Torvalds 已提交
828

829 830 831 832 833 834 835 836 837 838 839 840 841 842 843 844 845 846 847 848 849 850 851 852 853 854 855 856 857 858 859 860 861 862 863 864 865 866 867 868 869 870 871 872 873 874 875 876 877 878 879 880
		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;
881 882
		case Opt_labelsupport:
			break;
883 884 885 886
		default:
			rc = -EINVAL;
			printk(KERN_WARNING "SELinux:  unknown mount option\n");
			goto out_err;
L
Linus Torvalds 已提交
887 888 889

		}
	}
890

891 892 893 894 895 896 897 898 899 900 901
	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;
	}

902
	if (fscontext) {
903 904
		opts->mnt_opts[num_mnt_opts] = fscontext;
		opts->mnt_opts_flags[num_mnt_opts++] = FSCONTEXT_MNT;
905 906
	}
	if (context) {
907 908
		opts->mnt_opts[num_mnt_opts] = context;
		opts->mnt_opts_flags[num_mnt_opts++] = CONTEXT_MNT;
909 910
	}
	if (rootcontext) {
911 912
		opts->mnt_opts[num_mnt_opts] = rootcontext;
		opts->mnt_opts_flags[num_mnt_opts++] = ROOTCONTEXT_MNT;
913 914
	}
	if (defcontext) {
915 916
		opts->mnt_opts[num_mnt_opts] = defcontext;
		opts->mnt_opts_flags[num_mnt_opts++] = DEFCONTEXT_MNT;
917 918
	}

919 920 921
	opts->num_mnt_opts = num_mnt_opts;
	return 0;

922 923 924 925 926
out_err:
	kfree(context);
	kfree(defcontext);
	kfree(fscontext);
	kfree(rootcontext);
L
Linus Torvalds 已提交
927 928
	return rc;
}
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
/*
 * string mount options parsing and call set the sbsec
 */
static int superblock_doinit(struct super_block *sb, void *data)
{
	int rc = 0;
	char *options = data;
	struct security_mnt_opts opts;

	security_init_mnt_opts(&opts);

	if (!data)
		goto out;

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

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

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

out_err:
	security_free_mnt_opts(&opts);
	return rc;
}
L
Linus Torvalds 已提交
956

A
Adrian Bunk 已提交
957 958
static void selinux_write_opts(struct seq_file *m,
			       struct security_mnt_opts *opts)
959 960 961 962 963
{
	int i;
	char *prefix;

	for (i = 0; i < opts->num_mnt_opts; i++) {
964 965 966 967 968 969
		char *has_comma;

		if (opts->mnt_opts[i])
			has_comma = strchr(opts->mnt_opts[i], ',');
		else
			has_comma = NULL;
970 971 972 973 974 975 976 977 978 979 980 981 982 983

		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;
984 985 986 987
		case SE_SBLABELSUPP:
			seq_putc(m, ',');
			seq_puts(m, LABELSUPP_STR);
			continue;
988 989
		default:
			BUG();
990
			return;
991 992 993 994 995 996 997 998 999 1000 1001 1002 1003 1004 1005 1006 1007 1008
		};
		/* 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);
1009 1010 1011 1012
	if (rc) {
		/* before policy load we may get EINVAL, don't show anything */
		if (rc == -EINVAL)
			rc = 0;
1013
		return rc;
1014
	}
1015 1016 1017 1018 1019 1020 1021 1022

	selinux_write_opts(m, &opts);

	security_free_mnt_opts(&opts);

	return rc;
}

L
Linus Torvalds 已提交
1023 1024 1025 1026 1027 1028 1029 1030 1031 1032 1033 1034 1035 1036 1037 1038 1039 1040 1041 1042 1043 1044 1045
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;
}

1046 1047 1048 1049 1050 1051 1052 1053 1054 1055
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
1056 1057 1058 1059 1060 1061 1062 1063 1064 1065 1066 1067 1068 1069 1070 1071
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:
1072 1073 1074 1075
			if (default_protocol_stream(protocol))
				return SECCLASS_TCP_SOCKET;
			else
				return SECCLASS_RAWIP_SOCKET;
L
Linus Torvalds 已提交
1076
		case SOCK_DGRAM:
1077 1078 1079 1080
			if (default_protocol_dgram(protocol))
				return SECCLASS_UDP_SOCKET;
			else
				return SECCLASS_RAWIP_SOCKET;
J
James Morris 已提交
1081 1082
		case SOCK_DCCP:
			return SECCLASS_DCCP_SOCKET;
1083
		default:
L
Linus Torvalds 已提交
1084 1085 1086 1087 1088 1089 1090 1091 1092
			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;
1093
		case NETLINK_INET_DIAG:
L
Linus Torvalds 已提交
1094 1095 1096 1097 1098 1099 1100 1101 1102 1103 1104 1105 1106
			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;
1107 1108
		case NETLINK_KOBJECT_UEVENT:
			return SECCLASS_NETLINK_KOBJECT_UEVENT_SOCKET;
L
Linus Torvalds 已提交
1109 1110 1111 1112 1113 1114 1115
		default:
			return SECCLASS_NETLINK_SOCKET;
		}
	case PF_PACKET:
		return SECCLASS_PACKET_SOCKET;
	case PF_KEY:
		return SECCLASS_KEY_SOCKET;
1116 1117
	case PF_APPLETALK:
		return SECCLASS_APPLETALK_SOCKET;
L
Linus Torvalds 已提交
1118 1119 1120 1121 1122 1123
	}

	return SECCLASS_SOCKET;
}

#ifdef CONFIG_PROC_FS
1124
static int selinux_proc_get_sid(struct dentry *dentry,
L
Linus Torvalds 已提交
1125 1126 1127
				u16 tclass,
				u32 *sid)
{
1128 1129
	int rc;
	char *buffer, *path;
L
Linus Torvalds 已提交
1130

1131
	buffer = (char *)__get_free_page(GFP_KERNEL);
L
Linus Torvalds 已提交
1132 1133 1134
	if (!buffer)
		return -ENOMEM;

1135 1136 1137 1138 1139 1140 1141 1142 1143 1144 1145 1146
	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
1147 1148 1149 1150 1151
	}
	free_page((unsigned long)buffer);
	return rc;
}
#else
1152
static int selinux_proc_get_sid(struct dentry *dentry,
L
Linus Torvalds 已提交
1153 1154 1155 1156 1157 1158 1159 1160 1161 1162 1163 1164 1165 1166 1167 1168 1169 1170 1171 1172 1173 1174
				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;

1175
	mutex_lock(&isec->lock);
L
Linus Torvalds 已提交
1176
	if (isec->initialized)
1177
		goto out_unlock;
L
Linus Torvalds 已提交
1178 1179

	sbsec = inode->i_sb->s_security;
1180
	if (!(sbsec->flags & SE_SBINITIALIZED)) {
L
Linus Torvalds 已提交
1181 1182 1183 1184 1185 1186 1187
		/* 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);
1188
		goto out_unlock;
L
Linus Torvalds 已提交
1189 1190 1191 1192 1193 1194 1195 1196 1197 1198 1199 1200 1201 1202 1203 1204 1205 1206 1207
	}

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

		/* Need a dentry, since the xattr API requires one.
		   Life would be simpler if we could just pass the inode. */
		if (opt_dentry) {
			/* Called from d_instantiate or d_splice_alias. */
			dentry = dget(opt_dentry);
		} else {
			/* Called from selinux_complete_init, try to find a dentry. */
			dentry = d_find_alias(inode);
		}
		if (!dentry) {
1208 1209 1210 1211 1212 1213 1214 1215 1216
			/*
			 * 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.
			 */
1217
			goto out_unlock;
L
Linus Torvalds 已提交
1218 1219 1220
		}

		len = INITCONTEXTLEN;
1221
		context = kmalloc(len+1, GFP_NOFS);
L
Linus Torvalds 已提交
1222 1223 1224
		if (!context) {
			rc = -ENOMEM;
			dput(dentry);
1225
			goto out_unlock;
L
Linus Torvalds 已提交
1226
		}
1227
		context[len] = '\0';
L
Linus Torvalds 已提交
1228 1229 1230
		rc = inode->i_op->getxattr(dentry, XATTR_NAME_SELINUX,
					   context, len);
		if (rc == -ERANGE) {
1231 1232
			kfree(context);

L
Linus Torvalds 已提交
1233 1234 1235 1236 1237
			/* 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);
1238
				goto out_unlock;
L
Linus Torvalds 已提交
1239 1240
			}
			len = rc;
1241
			context = kmalloc(len+1, GFP_NOFS);
L
Linus Torvalds 已提交
1242 1243 1244
			if (!context) {
				rc = -ENOMEM;
				dput(dentry);
1245
				goto out_unlock;
L
Linus Torvalds 已提交
1246
			}
1247
			context[len] = '\0';
L
Linus Torvalds 已提交
1248 1249 1250 1251 1252 1253 1254
			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
1255
				printk(KERN_WARNING "SELinux: %s:  getxattr returned "
1256
				       "%d for dev=%s ino=%ld\n", __func__,
L
Linus Torvalds 已提交
1257 1258
				       -rc, inode->i_sb->s_id, inode->i_ino);
				kfree(context);
1259
				goto out_unlock;
L
Linus Torvalds 已提交
1260 1261 1262 1263 1264
			}
			/* Map ENODATA to the default file SID */
			sid = sbsec->def_sid;
			rc = 0;
		} else {
1265
			rc = security_context_to_sid_default(context, rc, &sid,
1266 1267
							     sbsec->def_sid,
							     GFP_NOFS);
L
Linus Torvalds 已提交
1268
			if (rc) {
1269 1270 1271 1272 1273 1274 1275 1276 1277 1278 1279 1280 1281
				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
1282 1283 1284 1285 1286 1287 1288 1289 1290 1291 1292 1293 1294 1295 1296 1297 1298 1299
				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);
1300 1301
		rc = security_transition_sid(isec->task_sid, sbsec->sid,
					     isec->sclass, NULL, &sid);
L
Linus Torvalds 已提交
1302
		if (rc)
1303
			goto out_unlock;
L
Linus Torvalds 已提交
1304 1305
		isec->sid = sid;
		break;
1306 1307 1308
	case SECURITY_FS_USE_MNTPOINT:
		isec->sid = sbsec->mntpoint_sid;
		break;
L
Linus Torvalds 已提交
1309
	default:
1310
		/* Default to the fs superblock SID. */
L
Linus Torvalds 已提交
1311 1312
		isec->sid = sbsec->sid;

1313
		if ((sbsec->flags & SE_SBPROC) && !S_ISLNK(inode->i_mode)) {
1314
			if (opt_dentry) {
L
Linus Torvalds 已提交
1315
				isec->sclass = inode_mode_to_security_class(inode->i_mode);
1316
				rc = selinux_proc_get_sid(opt_dentry,
L
Linus Torvalds 已提交
1317 1318 1319
							  isec->sclass,
							  &sid);
				if (rc)
1320
					goto out_unlock;
L
Linus Torvalds 已提交
1321 1322 1323 1324 1325 1326 1327 1328
				isec->sid = sid;
			}
		}
		break;
	}

	isec->initialized = 1;

1329 1330
out_unlock:
	mutex_unlock(&isec->lock);
L
Linus Torvalds 已提交
1331 1332 1333 1334 1335 1336 1337 1338 1339 1340 1341 1342 1343 1344 1345 1346 1347 1348 1349 1350 1351 1352 1353 1354 1355 1356 1357 1358 1359 1360 1361 1362 1363
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
1364 1365 1366 1367 1368 1369 1370 1371 1372 1373 1374 1375 1376
/*
 * 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);
}

1377
/*
1378
 * Check permission between a pair of tasks, e.g. signal checks,
1379 1380
 * fork check, ptrace check, etc.
 * tsk1 is the actor and tsk2 is the target
1381
 * - this uses the default subjective creds of tsk1
1382 1383 1384
 */
static int task_has_perm(const struct task_struct *tsk1,
			 const struct task_struct *tsk2,
L
Linus Torvalds 已提交
1385 1386
			 u32 perms)
{
1387 1388
	const struct task_security_struct *__tsec1, *__tsec2;
	u32 sid1, sid2;
L
Linus Torvalds 已提交
1389

1390 1391 1392 1393 1394
	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
1395 1396
}

1397 1398 1399 1400 1401 1402 1403 1404 1405 1406 1407 1408 1409 1410 1411 1412
/*
 * 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);
}

1413 1414 1415 1416
#if CAP_LAST_CAP > 63
#error Fix SELinux to handle capabilities > 63.
#endif

L
Linus Torvalds 已提交
1417 1418
/* Check whether a task is allowed to use a capability. */
static int task_has_capability(struct task_struct *tsk,
1419
			       const struct cred *cred,
1420
			       int cap, int audit)
L
Linus Torvalds 已提交
1421
{
1422
	struct common_audit_data ad;
1423
	struct av_decision avd;
1424
	u16 sclass;
1425
	u32 sid = cred_sid(cred);
1426
	u32 av = CAP_TO_MASK(cap);
1427
	int rc;
L
Linus Torvalds 已提交
1428

1429
	COMMON_AUDIT_DATA_INIT(&ad, CAP);
L
Linus Torvalds 已提交
1430 1431 1432
	ad.tsk = tsk;
	ad.u.cap = cap;

1433 1434 1435 1436 1437 1438 1439 1440 1441 1442 1443
	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();
1444
		return -EINVAL;
1445
	}
1446

1447
	rc = avc_has_perm_noaudit(sid, sid, sclass, av, 0, &avd);
1448 1449 1450 1451 1452
	if (audit == SECURITY_CAP_AUDIT) {
		int rc2 = avc_audit(sid, sid, sclass, av, &avd, rc, &ad, 0);
		if (rc2)
			return rc2;
	}
1453
	return rc;
L
Linus Torvalds 已提交
1454 1455 1456 1457 1458 1459
}

/* Check whether a task is allowed to use a system operation. */
static int task_has_system(struct task_struct *tsk,
			   u32 perms)
{
1460
	u32 sid = task_sid(tsk);
L
Linus Torvalds 已提交
1461

1462
	return avc_has_perm(sid, SECINITSID_KERNEL,
L
Linus Torvalds 已提交
1463 1464 1465 1466 1467 1468
			    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). */
1469
static int inode_has_perm(const struct cred *cred,
L
Linus Torvalds 已提交
1470 1471
			  struct inode *inode,
			  u32 perms,
1472 1473
			  struct common_audit_data *adp,
			  unsigned flags)
L
Linus Torvalds 已提交
1474 1475
{
	struct inode_security_struct *isec;
1476
	u32 sid;
L
Linus Torvalds 已提交
1477

1478 1479
	validate_creds(cred);

1480
	if (unlikely(IS_PRIVATE(inode)))
1481 1482
		return 0;

1483
	sid = cred_sid(cred);
L
Linus Torvalds 已提交
1484 1485
	isec = inode->i_security;

1486
	return avc_has_perm_flags(sid, isec->sid, isec->sclass, perms, adp, flags);
L
Linus Torvalds 已提交
1487 1488
}

1489 1490 1491 1492 1493 1494 1495 1496 1497 1498 1499 1500
static int inode_has_perm_noadp(const struct cred *cred,
				struct inode *inode,
				u32 perms,
				unsigned flags)
{
	struct common_audit_data ad;

	COMMON_AUDIT_DATA_INIT(&ad, INODE);
	ad.u.inode = inode;
	return inode_has_perm(cred, inode, perms, &ad, flags);
}

L
Linus Torvalds 已提交
1501 1502 1503
/* 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. */
1504
static inline int dentry_has_perm(const struct cred *cred,
L
Linus Torvalds 已提交
1505 1506 1507 1508
				  struct dentry *dentry,
				  u32 av)
{
	struct inode *inode = dentry->d_inode;
1509
	struct common_audit_data ad;
1510

E
Eric Paris 已提交
1511 1512 1513 1514 1515 1516 1517 1518 1519 1520 1521 1522 1523 1524 1525
	COMMON_AUDIT_DATA_INIT(&ad, DENTRY);
	ad.u.dentry = dentry;
	return inode_has_perm(cred, inode, av, &ad, 0);
}

/* 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;

1526
	COMMON_AUDIT_DATA_INIT(&ad, PATH);
E
Eric Paris 已提交
1527
	ad.u.path = *path;
1528
	return inode_has_perm(cred, inode, av, &ad, 0);
L
Linus Torvalds 已提交
1529 1530 1531 1532 1533 1534 1535 1536 1537 1538
}

/* 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. */
1539 1540 1541
static int file_has_perm(const struct cred *cred,
			 struct file *file,
			 u32 av)
L
Linus Torvalds 已提交
1542 1543
{
	struct file_security_struct *fsec = file->f_security;
1544
	struct inode *inode = file->f_path.dentry->d_inode;
1545
	struct common_audit_data ad;
1546
	u32 sid = cred_sid(cred);
L
Linus Torvalds 已提交
1547 1548
	int rc;

1549 1550
	COMMON_AUDIT_DATA_INIT(&ad, PATH);
	ad.u.path = file->f_path;
L
Linus Torvalds 已提交
1551

1552 1553
	if (sid != fsec->sid) {
		rc = avc_has_perm(sid, fsec->sid,
L
Linus Torvalds 已提交
1554 1555 1556 1557
				  SECCLASS_FD,
				  FD__USE,
				  &ad);
		if (rc)
1558
			goto out;
L
Linus Torvalds 已提交
1559 1560 1561
	}

	/* av is zero if only checking access to the descriptor. */
1562
	rc = 0;
L
Linus Torvalds 已提交
1563
	if (av)
1564
		rc = inode_has_perm(cred, inode, av, &ad, 0);
L
Linus Torvalds 已提交
1565

1566 1567
out:
	return rc;
L
Linus Torvalds 已提交
1568 1569 1570 1571 1572 1573 1574
}

/* Check whether a task can create a file. */
static int may_create(struct inode *dir,
		      struct dentry *dentry,
		      u16 tclass)
{
1575
	const struct task_security_struct *tsec = current_security();
L
Linus Torvalds 已提交
1576 1577
	struct inode_security_struct *dsec;
	struct superblock_security_struct *sbsec;
1578
	u32 sid, newsid;
1579
	struct common_audit_data ad;
L
Linus Torvalds 已提交
1580 1581 1582 1583 1584
	int rc;

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

1585 1586 1587
	sid = tsec->sid;
	newsid = tsec->create_sid;

1588 1589
	COMMON_AUDIT_DATA_INIT(&ad, DENTRY);
	ad.u.dentry = dentry;
L
Linus Torvalds 已提交
1590

1591
	rc = avc_has_perm(sid, dsec->sid, SECCLASS_DIR,
L
Linus Torvalds 已提交
1592 1593 1594 1595 1596
			  DIR__ADD_NAME | DIR__SEARCH,
			  &ad);
	if (rc)
		return rc;

1597
	if (!newsid || !(sbsec->flags & SE_SBLABELSUPP)) {
1598 1599
		rc = security_transition_sid(sid, dsec->sid, tclass,
					     &dentry->d_name, &newsid);
L
Linus Torvalds 已提交
1600 1601 1602 1603
		if (rc)
			return rc;
	}

1604
	rc = avc_has_perm(sid, newsid, tclass, FILE__CREATE, &ad);
L
Linus Torvalds 已提交
1605 1606 1607 1608 1609 1610 1611 1612
	if (rc)
		return rc;

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

1613 1614 1615 1616
/* Check whether a task can create a key. */
static int may_create_key(u32 ksid,
			  struct task_struct *ctx)
{
1617
	u32 sid = task_sid(ctx);
1618

1619
	return avc_has_perm(sid, ksid, SECCLASS_KEY, KEY__CREATE, NULL);
1620 1621
}

1622 1623 1624
#define MAY_LINK	0
#define MAY_UNLINK	1
#define MAY_RMDIR	2
L
Linus Torvalds 已提交
1625 1626 1627 1628 1629 1630 1631 1632

/* 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;
1633
	struct common_audit_data ad;
1634
	u32 sid = current_sid();
L
Linus Torvalds 已提交
1635 1636 1637 1638 1639 1640
	u32 av;
	int rc;

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

1641 1642
	COMMON_AUDIT_DATA_INIT(&ad, DENTRY);
	ad.u.dentry = dentry;
L
Linus Torvalds 已提交
1643 1644 1645

	av = DIR__SEARCH;
	av |= (kind ? DIR__REMOVE_NAME : DIR__ADD_NAME);
1646
	rc = avc_has_perm(sid, dsec->sid, SECCLASS_DIR, av, &ad);
L
Linus Torvalds 已提交
1647 1648 1649 1650 1651 1652 1653 1654 1655 1656 1657 1658 1659 1660
	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
1661 1662
		printk(KERN_WARNING "SELinux: %s:  unrecognized kind %d\n",
			__func__, kind);
L
Linus Torvalds 已提交
1663 1664 1665
		return 0;
	}

1666
	rc = avc_has_perm(sid, isec->sid, isec->sclass, av, &ad);
L
Linus Torvalds 已提交
1667 1668 1669 1670 1671 1672 1673 1674 1675
	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;
1676
	struct common_audit_data ad;
1677
	u32 sid = current_sid();
L
Linus Torvalds 已提交
1678 1679 1680 1681 1682 1683 1684 1685 1686
	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;

1687
	COMMON_AUDIT_DATA_INIT(&ad, DENTRY);
L
Linus Torvalds 已提交
1688

1689
	ad.u.dentry = old_dentry;
1690
	rc = avc_has_perm(sid, old_dsec->sid, SECCLASS_DIR,
L
Linus Torvalds 已提交
1691 1692 1693
			  DIR__REMOVE_NAME | DIR__SEARCH, &ad);
	if (rc)
		return rc;
1694
	rc = avc_has_perm(sid, old_isec->sid,
L
Linus Torvalds 已提交
1695 1696 1697 1698
			  old_isec->sclass, FILE__RENAME, &ad);
	if (rc)
		return rc;
	if (old_is_dir && new_dir != old_dir) {
1699
		rc = avc_has_perm(sid, old_isec->sid,
L
Linus Torvalds 已提交
1700 1701 1702 1703 1704
				  old_isec->sclass, DIR__REPARENT, &ad);
		if (rc)
			return rc;
	}

1705
	ad.u.dentry = new_dentry;
L
Linus Torvalds 已提交
1706 1707 1708
	av = DIR__ADD_NAME | DIR__SEARCH;
	if (new_dentry->d_inode)
		av |= DIR__REMOVE_NAME;
1709
	rc = avc_has_perm(sid, new_dsec->sid, SECCLASS_DIR, av, &ad);
L
Linus Torvalds 已提交
1710 1711 1712 1713 1714
	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);
1715
		rc = avc_has_perm(sid, new_isec->sid,
L
Linus Torvalds 已提交
1716 1717 1718 1719 1720 1721 1722 1723 1724 1725
				  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. */
1726
static int superblock_has_perm(const struct cred *cred,
L
Linus Torvalds 已提交
1727 1728
			       struct super_block *sb,
			       u32 perms,
1729
			       struct common_audit_data *ad)
L
Linus Torvalds 已提交
1730 1731
{
	struct superblock_security_struct *sbsec;
1732
	u32 sid = cred_sid(cred);
L
Linus Torvalds 已提交
1733 1734

	sbsec = sb->s_security;
1735
	return avc_has_perm(sid, sbsec->sid, SECCLASS_FILESYSTEM, perms, ad);
L
Linus Torvalds 已提交
1736 1737 1738 1739 1740 1741 1742 1743 1744 1745 1746 1747 1748 1749 1750 1751 1752 1753 1754 1755 1756 1757 1758 1759 1760 1761 1762 1763 1764 1765
}

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

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

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

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

	return av;
}

1766 1767 1768 1769 1770 1771 1772 1773 1774 1775 1776 1777 1778 1779 1780 1781 1782 1783 1784 1785 1786 1787 1788
/* 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
1789
/*
1790
 * Convert a file to an access vector and include the correct open
E
Eric Paris 已提交
1791 1792
 * open permission.
 */
1793
static inline u32 open_file_to_av(struct file *file)
E
Eric Paris 已提交
1794
{
1795
	u32 av = file_to_av(file);
E
Eric Paris 已提交
1796

1797 1798 1799
	if (selinux_policycap_openperm)
		av |= FILE__OPEN;

E
Eric Paris 已提交
1800 1801 1802
	return av;
}

L
Linus Torvalds 已提交
1803 1804
/* Hook functions begin here. */

1805
static int selinux_ptrace_access_check(struct task_struct *child,
1806
				     unsigned int mode)
L
Linus Torvalds 已提交
1807 1808 1809
{
	int rc;

1810
	rc = cap_ptrace_access_check(child, mode);
L
Linus Torvalds 已提交
1811 1812 1813
	if (rc)
		return rc;

1814
	if (mode == PTRACE_MODE_READ) {
1815 1816 1817
		u32 sid = current_sid();
		u32 csid = task_sid(child);
		return avc_has_perm(sid, csid, SECCLASS_FILE, FILE__READ, NULL);
1818 1819
	}

1820
	return current_has_perm(child, PROCESS__PTRACE);
1821 1822 1823 1824 1825 1826
}

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

1827
	rc = cap_ptrace_traceme(parent);
1828 1829 1830 1831
	if (rc)
		return rc;

	return task_has_perm(parent, current, PROCESS__PTRACE);
L
Linus Torvalds 已提交
1832 1833 1834
}

static int selinux_capget(struct task_struct *target, kernel_cap_t *effective,
1835
			  kernel_cap_t *inheritable, kernel_cap_t *permitted)
L
Linus Torvalds 已提交
1836 1837 1838
{
	int error;

1839
	error = current_has_perm(target, PROCESS__GETCAP);
L
Linus Torvalds 已提交
1840 1841 1842
	if (error)
		return error;

1843
	return cap_capget(target, effective, inheritable, permitted);
L
Linus Torvalds 已提交
1844 1845
}

D
David Howells 已提交
1846 1847 1848 1849
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
1850 1851 1852
{
	int error;

1853
	error = cap_capset(new, old,
D
David Howells 已提交
1854
				      effective, inheritable, permitted);
L
Linus Torvalds 已提交
1855 1856 1857
	if (error)
		return error;

D
David Howells 已提交
1858
	return cred_has_perm(old, new, PROCESS__SETCAP);
L
Linus Torvalds 已提交
1859 1860
}

1861 1862 1863 1864 1865 1866 1867 1868 1869 1870
/*
 * (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.
 */

1871
static int selinux_capable(struct task_struct *tsk, const struct cred *cred,
1872
			   struct user_namespace *ns, int cap, int audit)
L
Linus Torvalds 已提交
1873 1874 1875
{
	int rc;

1876
	rc = cap_capable(tsk, cred, ns, cap, audit);
L
Linus Torvalds 已提交
1877 1878 1879
	if (rc)
		return rc;

1880
	return task_has_capability(tsk, cred, cap, audit);
L
Linus Torvalds 已提交
1881 1882 1883 1884
}

static int selinux_quotactl(int cmds, int type, int id, struct super_block *sb)
{
1885
	const struct cred *cred = current_cred();
L
Linus Torvalds 已提交
1886 1887 1888 1889 1890 1891
	int rc = 0;

	if (!sb)
		return 0;

	switch (cmds) {
1892 1893 1894 1895 1896
	case Q_SYNC:
	case Q_QUOTAON:
	case Q_QUOTAOFF:
	case Q_SETINFO:
	case Q_SETQUOTA:
1897
		rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAMOD, NULL);
1898 1899 1900 1901
		break;
	case Q_GETFMT:
	case Q_GETINFO:
	case Q_GETQUOTA:
1902
		rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAGET, NULL);
1903 1904 1905 1906
		break;
	default:
		rc = 0;  /* let the kernel handle invalid cmds */
		break;
L
Linus Torvalds 已提交
1907 1908 1909 1910 1911 1912
	}
	return rc;
}

static int selinux_quota_on(struct dentry *dentry)
{
1913 1914
	const struct cred *cred = current_cred();

E
Eric Paris 已提交
1915
	return dentry_has_perm(cred, dentry, FILE__QUOTAON);
L
Linus Torvalds 已提交
1916 1917
}

1918
static int selinux_syslog(int type)
L
Linus Torvalds 已提交
1919 1920 1921 1922
{
	int rc;

	switch (type) {
1923 1924
	case SYSLOG_ACTION_READ_ALL:	/* Read last kernel messages */
	case SYSLOG_ACTION_SIZE_BUFFER:	/* Return size of the log buffer */
1925 1926
		rc = task_has_system(current, SYSTEM__SYSLOG_READ);
		break;
1927 1928 1929 1930
	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:
1931 1932
		rc = task_has_system(current, SYSTEM__SYSLOG_CONSOLE);
		break;
1933 1934 1935 1936 1937
	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 */
1938 1939 1940
	default:
		rc = task_has_system(current, SYSTEM__SYSLOG_MOD);
		break;
L
Linus Torvalds 已提交
1941 1942 1943 1944 1945 1946 1947 1948 1949 1950 1951 1952
	}
	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.
 */
1953
static int selinux_vm_enough_memory(struct mm_struct *mm, long pages)
L
Linus Torvalds 已提交
1954 1955 1956
{
	int rc, cap_sys_admin = 0;

1957 1958
	rc = selinux_capable(current, current_cred(),
			     &init_user_ns, CAP_SYS_ADMIN,
1959
			     SECURITY_CAP_NOAUDIT);
L
Linus Torvalds 已提交
1960 1961 1962
	if (rc == 0)
		cap_sys_admin = 1;

1963
	return __vm_enough_memory(mm, pages, cap_sys_admin);
L
Linus Torvalds 已提交
1964 1965 1966 1967
}

/* binprm security operations */

1968
static int selinux_bprm_set_creds(struct linux_binprm *bprm)
L
Linus Torvalds 已提交
1969
{
1970 1971
	const struct task_security_struct *old_tsec;
	struct task_security_struct *new_tsec;
L
Linus Torvalds 已提交
1972
	struct inode_security_struct *isec;
1973
	struct common_audit_data ad;
1974
	struct inode *inode = bprm->file->f_path.dentry->d_inode;
L
Linus Torvalds 已提交
1975 1976
	int rc;

1977
	rc = cap_bprm_set_creds(bprm);
L
Linus Torvalds 已提交
1978 1979 1980
	if (rc)
		return rc;

1981 1982 1983
	/* SELinux context only depends on initial program or script and not
	 * the script interpreter */
	if (bprm->cred_prepared)
L
Linus Torvalds 已提交
1984 1985
		return 0;

1986 1987
	old_tsec = current_security();
	new_tsec = bprm->cred->security;
L
Linus Torvalds 已提交
1988 1989 1990
	isec = inode->i_security;

	/* Default to the current task SID. */
1991 1992
	new_tsec->sid = old_tsec->sid;
	new_tsec->osid = old_tsec->sid;
L
Linus Torvalds 已提交
1993

1994
	/* Reset fs, key, and sock SIDs on execve. */
1995 1996 1997
	new_tsec->create_sid = 0;
	new_tsec->keycreate_sid = 0;
	new_tsec->sockcreate_sid = 0;
L
Linus Torvalds 已提交
1998

1999 2000
	if (old_tsec->exec_sid) {
		new_tsec->sid = old_tsec->exec_sid;
L
Linus Torvalds 已提交
2001
		/* Reset exec SID on execve. */
2002
		new_tsec->exec_sid = 0;
L
Linus Torvalds 已提交
2003 2004
	} else {
		/* Check for a default transition on this program. */
2005
		rc = security_transition_sid(old_tsec->sid, isec->sid,
2006 2007
					     SECCLASS_PROCESS, NULL,
					     &new_tsec->sid);
L
Linus Torvalds 已提交
2008 2009 2010 2011
		if (rc)
			return rc;
	}

2012 2013
	COMMON_AUDIT_DATA_INIT(&ad, PATH);
	ad.u.path = bprm->file->f_path;
L
Linus Torvalds 已提交
2014

J
Josef Sipek 已提交
2015
	if (bprm->file->f_path.mnt->mnt_flags & MNT_NOSUID)
2016
		new_tsec->sid = old_tsec->sid;
L
Linus Torvalds 已提交
2017

2018 2019
	if (new_tsec->sid == old_tsec->sid) {
		rc = avc_has_perm(old_tsec->sid, isec->sid,
L
Linus Torvalds 已提交
2020 2021 2022 2023 2024
				  SECCLASS_FILE, FILE__EXECUTE_NO_TRANS, &ad);
		if (rc)
			return rc;
	} else {
		/* Check permissions for the transition. */
2025
		rc = avc_has_perm(old_tsec->sid, new_tsec->sid,
L
Linus Torvalds 已提交
2026 2027 2028 2029
				  SECCLASS_PROCESS, PROCESS__TRANSITION, &ad);
		if (rc)
			return rc;

2030
		rc = avc_has_perm(new_tsec->sid, isec->sid,
L
Linus Torvalds 已提交
2031 2032 2033 2034
				  SECCLASS_FILE, FILE__ENTRYPOINT, &ad);
		if (rc)
			return rc;

2035 2036 2037 2038 2039 2040 2041 2042 2043 2044 2045 2046 2047 2048 2049 2050 2051 2052
		/* 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();
2053
			tracer = ptrace_parent(current);
2054 2055 2056 2057 2058 2059 2060 2061 2062 2063 2064 2065 2066 2067
			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
2068

2069 2070
		/* Clear any possibly unsafe personality bits on exec: */
		bprm->per_clear |= PER_CLEAR_ON_SETID;
L
Linus Torvalds 已提交
2071 2072 2073 2074 2075
	}

	return 0;
}

2076
static int selinux_bprm_secureexec(struct linux_binprm *bprm)
L
Linus Torvalds 已提交
2077
{
2078
	const struct task_security_struct *tsec = current_security();
2079
	u32 sid, osid;
L
Linus Torvalds 已提交
2080 2081
	int atsecure = 0;

2082 2083 2084 2085
	sid = tsec->sid;
	osid = tsec->osid;

	if (osid != sid) {
L
Linus Torvalds 已提交
2086 2087 2088
		/* Enable secure mode for SIDs transitions unless
		   the noatsecure permission is granted between
		   the two SIDs, i.e. ahp returns 0. */
2089
		atsecure = avc_has_perm(osid, sid,
2090 2091
					SECCLASS_PROCESS,
					PROCESS__NOATSECURE, NULL);
L
Linus Torvalds 已提交
2092 2093
	}

2094
	return (atsecure || cap_bprm_secureexec(bprm));
L
Linus Torvalds 已提交
2095 2096 2097
}

/* Derived from fs/exec.c:flush_old_files. */
2098 2099
static inline void flush_unauthorized_files(const struct cred *cred,
					    struct files_struct *files)
L
Linus Torvalds 已提交
2100
{
2101
	struct common_audit_data ad;
L
Linus Torvalds 已提交
2102
	struct file *file, *devnull = NULL;
2103
	struct tty_struct *tty;
2104
	struct fdtable *fdt;
L
Linus Torvalds 已提交
2105
	long j = -1;
2106
	int drop_tty = 0;
L
Linus Torvalds 已提交
2107

2108
	tty = get_current_tty();
L
Linus Torvalds 已提交
2109
	if (tty) {
N
Nick Piggin 已提交
2110
		spin_lock(&tty_files_lock);
2111
		if (!list_empty(&tty->tty_files)) {
N
Nick Piggin 已提交
2112
			struct tty_file_private *file_priv;
2113 2114
			struct inode *inode;

L
Linus Torvalds 已提交
2115 2116 2117 2118 2119
			/* Revalidate access to controlling tty.
			   Use inode_has_perm on the tty inode directly rather
			   than using file_has_perm, as this particular open
			   file may belong to another process and we are only
			   interested in the inode-based check here. */
N
Nick Piggin 已提交
2120 2121 2122
			file_priv = list_first_entry(&tty->tty_files,
						struct tty_file_private, list);
			file = file_priv->file;
2123
			inode = file->f_path.dentry->d_inode;
2124 2125
			if (inode_has_perm_noadp(cred, inode,
					   FILE__READ | FILE__WRITE, 0)) {
2126
				drop_tty = 1;
L
Linus Torvalds 已提交
2127 2128
			}
		}
N
Nick Piggin 已提交
2129
		spin_unlock(&tty_files_lock);
A
Alan Cox 已提交
2130
		tty_kref_put(tty);
L
Linus Torvalds 已提交
2131
	}
2132 2133 2134
	/* Reset controlling tty. */
	if (drop_tty)
		no_tty();
L
Linus Torvalds 已提交
2135 2136 2137

	/* Revalidate access to inherited open files. */

2138
	COMMON_AUDIT_DATA_INIT(&ad, INODE);
L
Linus Torvalds 已提交
2139 2140 2141 2142 2143 2144 2145 2146

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

		j++;
		i = j * __NFDBITS;
2147
		fdt = files_fdtable(files);
2148
		if (i >= fdt->max_fds)
L
Linus Torvalds 已提交
2149
			break;
2150
		set = fdt->open_fds->fds_bits[j];
L
Linus Torvalds 已提交
2151 2152 2153
		if (!set)
			continue;
		spin_unlock(&files->file_lock);
2154
		for ( ; set ; i++, set >>= 1) {
L
Linus Torvalds 已提交
2155 2156 2157 2158
			if (set & 1) {
				file = fget(i);
				if (!file)
					continue;
2159
				if (file_has_perm(cred,
L
Linus Torvalds 已提交
2160 2161 2162 2163 2164 2165 2166 2167 2168 2169 2170
						  file,
						  file_to_av(file))) {
					sys_close(i);
					fd = get_unused_fd();
					if (fd != i) {
						if (fd >= 0)
							put_unused_fd(fd);
						fput(file);
						continue;
					}
					if (devnull) {
2171
						get_file(devnull);
L
Linus Torvalds 已提交
2172
					} else {
2173 2174 2175 2176
						devnull = dentry_open(
							dget(selinux_null),
							mntget(selinuxfs_mount),
							O_RDWR, cred);
2177 2178
						if (IS_ERR(devnull)) {
							devnull = NULL;
L
Linus Torvalds 已提交
2179 2180 2181 2182 2183 2184 2185 2186 2187 2188 2189 2190 2191 2192 2193 2194
							put_unused_fd(fd);
							fput(file);
							continue;
						}
					}
					fd_install(fd, devnull);
				}
				fput(file);
			}
		}
		spin_lock(&files->file_lock);

	}
	spin_unlock(&files->file_lock);
}

2195 2196 2197 2198
/*
 * 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
2199
{
2200 2201 2202
	struct task_security_struct *new_tsec;
	struct rlimit *rlim, *initrlim;
	int rc, i;
D
David Howells 已提交
2203

2204 2205 2206
	new_tsec = bprm->cred->security;
	if (new_tsec->sid == new_tsec->osid)
		return;
L
Linus Torvalds 已提交
2207

2208 2209
	/* Close files for which the new task SID is not authorized. */
	flush_unauthorized_files(bprm->cred, current->files);
R
Roland McGrath 已提交
2210

2211 2212
	/* Always clear parent death signal on SID transitions. */
	current->pdeath_signal = 0;
R
Roland McGrath 已提交
2213

2214 2215 2216 2217 2218 2219 2220 2221 2222 2223 2224 2225 2226
	/* 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) {
2227 2228
		/* protect against do_prlimit() */
		task_lock(current);
2229 2230 2231 2232
		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
2233
		}
2234 2235
		task_unlock(current);
		update_rlimit_cpu(current, rlimit(RLIMIT_CPU));
L
Linus Torvalds 已提交
2236 2237 2238 2239
	}
}

/*
2240 2241
 * Clean up the process immediately after the installation of new credentials
 * due to exec
L
Linus Torvalds 已提交
2242
 */
2243
static void selinux_bprm_committed_creds(struct linux_binprm *bprm)
L
Linus Torvalds 已提交
2244
{
2245
	const struct task_security_struct *tsec = current_security();
L
Linus Torvalds 已提交
2246
	struct itimerval itimer;
2247
	u32 osid, sid;
L
Linus Torvalds 已提交
2248 2249
	int rc, i;

2250 2251 2252 2253
	osid = tsec->osid;
	sid = tsec->sid;

	if (sid == osid)
L
Linus Torvalds 已提交
2254 2255
		return;

2256 2257 2258 2259 2260 2261 2262 2263
	/* 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
2264 2265 2266 2267 2268
	if (rc) {
		memset(&itimer, 0, sizeof itimer);
		for (i = 0; i < 3; i++)
			do_setitimer(i, &itimer, NULL);
		spin_lock_irq(&current->sighand->siglock);
2269 2270 2271 2272 2273
		if (!(current->signal->flags & SIGNAL_GROUP_EXIT)) {
			__flush_signals(current);
			flush_signal_handlers(current, 1);
			sigemptyset(&current->blocked);
		}
L
Linus Torvalds 已提交
2274 2275 2276
		spin_unlock_irq(&current->sighand->siglock);
	}

2277 2278
	/* Wake up the parent if it is waiting so that it can recheck
	 * wait permission to the new task SID. */
2279
	read_lock(&tasklist_lock);
2280
	__wake_up_parent(current, current->real_parent);
2281
	read_unlock(&tasklist_lock);
L
Linus Torvalds 已提交
2282 2283 2284 2285 2286 2287 2288 2289 2290 2291 2292 2293 2294 2295 2296 2297 2298 2299 2300 2301 2302 2303 2304 2305
}

/* 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)
{
2306 2307 2308
	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) ||
2309 2310
		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
2311 2312 2313 2314 2315 2316 2317
}

static inline void take_option(char **to, char *from, int *first, int len)
{
	if (!*first) {
		**to = ',';
		*to += 1;
2318
	} else
L
Linus Torvalds 已提交
2319 2320 2321 2322 2323
		*first = 0;
	memcpy(*to, from, len);
	*to += len;
}

2324 2325
static inline void take_selinux_option(char **to, char *from, int *first,
				       int len)
2326 2327 2328 2329 2330 2331
{
	int current_size = 0;

	if (!*first) {
		**to = '|';
		*to += 1;
2332
	} else
2333 2334 2335 2336 2337 2338 2339 2340 2341 2342 2343 2344
		*first = 0;

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

2345
static int selinux_sb_copy_data(char *orig, char *copy)
L
Linus Torvalds 已提交
2346 2347 2348 2349
{
	int fnosec, fsec, rc = 0;
	char *in_save, *in_curr, *in_end;
	char *sec_curr, *nosec_save, *nosec;
2350
	int open_quote = 0;
L
Linus Torvalds 已提交
2351 2352 2353 2354 2355 2356 2357 2358 2359 2360 2361 2362 2363 2364 2365

	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 {
2366 2367 2368 2369
		if (*in_end == '"')
			open_quote = !open_quote;
		if ((*in_end == ',' && open_quote == 0) ||
				*in_end == '\0') {
L
Linus Torvalds 已提交
2370 2371 2372
			int len = in_end - in_curr;

			if (selinux_option(in_curr, len))
2373
				take_selinux_option(&sec_curr, in_curr, &fsec, len);
L
Linus Torvalds 已提交
2374 2375 2376 2377 2378 2379 2380
			else
				take_option(&nosec, in_curr, &fnosec, len);

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

2381
	strcpy(in_save, nosec_save);
2382
	free_page((unsigned long)nosec_save);
L
Linus Torvalds 已提交
2383 2384 2385 2386
out:
	return rc;
}

2387 2388 2389 2390 2391 2392 2393 2394 2395 2396 2397 2398 2399 2400 2401 2402 2403 2404 2405 2406 2407 2408 2409 2410 2411 2412 2413 2414 2415 2416 2417 2418 2419 2420 2421 2422 2423 2424 2425 2426 2427 2428 2429 2430 2431 2432 2433 2434 2435 2436 2437 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
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;

		if (flags[i] == SE_SBLABELSUPP)
			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"
			       "(%s) failed for (dev %s, type %s) errno=%d\n",
			       mount_options[i], sb->s_id, sb->s_type->name, rc);
			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 "
	       "during remount (dev %s, type=%s)\n", sb->s_id,
	       sb->s_type->name);
	goto out_free_opts;
}

2472
static int selinux_sb_kern_mount(struct super_block *sb, int flags, void *data)
L
Linus Torvalds 已提交
2473
{
2474
	const struct cred *cred = current_cred();
2475
	struct common_audit_data ad;
L
Linus Torvalds 已提交
2476 2477 2478 2479 2480 2481
	int rc;

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

2482 2483 2484 2485
	/* Allow all mounts performed by the kernel */
	if (flags & MS_KERNMOUNT)
		return 0;

2486 2487
	COMMON_AUDIT_DATA_INIT(&ad, DENTRY);
	ad.u.dentry = sb->s_root;
2488
	return superblock_has_perm(cred, sb, FILESYSTEM__MOUNT, &ad);
L
Linus Torvalds 已提交
2489 2490
}

2491
static int selinux_sb_statfs(struct dentry *dentry)
L
Linus Torvalds 已提交
2492
{
2493
	const struct cred *cred = current_cred();
2494
	struct common_audit_data ad;
L
Linus Torvalds 已提交
2495

2496 2497
	COMMON_AUDIT_DATA_INIT(&ad, DENTRY);
	ad.u.dentry = dentry->d_sb->s_root;
2498
	return superblock_has_perm(cred, dentry->d_sb, FILESYSTEM__GETATTR, &ad);
L
Linus Torvalds 已提交
2499 2500
}

2501
static int selinux_mount(char *dev_name,
2502
			 struct path *path,
2503 2504 2505
			 char *type,
			 unsigned long flags,
			 void *data)
L
Linus Torvalds 已提交
2506
{
2507
	const struct cred *cred = current_cred();
L
Linus Torvalds 已提交
2508 2509

	if (flags & MS_REMOUNT)
2510
		return superblock_has_perm(cred, path->mnt->mnt_sb,
2511
					   FILESYSTEM__REMOUNT, NULL);
L
Linus Torvalds 已提交
2512
	else
E
Eric Paris 已提交
2513
		return path_has_perm(cred, path, FILE__MOUNTON);
L
Linus Torvalds 已提交
2514 2515 2516 2517
}

static int selinux_umount(struct vfsmount *mnt, int flags)
{
2518
	const struct cred *cred = current_cred();
L
Linus Torvalds 已提交
2519

2520
	return superblock_has_perm(cred, mnt->mnt_sb,
2521
				   FILESYSTEM__UNMOUNT, NULL);
L
Linus Torvalds 已提交
2522 2523 2524 2525 2526 2527 2528 2529 2530 2531 2532 2533 2534 2535
}

/* 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);
}

2536
static int selinux_inode_init_security(struct inode *inode, struct inode *dir,
2537 2538
				       const struct qstr *qstr, char **name,
				       void **value, size_t *len)
2539
{
2540
	const struct task_security_struct *tsec = current_security();
2541 2542
	struct inode_security_struct *dsec;
	struct superblock_security_struct *sbsec;
2543
	u32 sid, newsid, clen;
2544
	int rc;
2545
	char *namep = NULL, *context;
2546 2547 2548 2549

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

2550 2551 2552
	sid = tsec->sid;
	newsid = tsec->create_sid;

2553 2554 2555 2556
	if ((sbsec->flags & SE_SBINITIALIZED) &&
	    (sbsec->behavior == SECURITY_FS_USE_MNTPOINT))
		newsid = sbsec->mntpoint_sid;
	else if (!newsid || !(sbsec->flags & SE_SBLABELSUPP)) {
2557
		rc = security_transition_sid(sid, dsec->sid,
2558
					     inode_mode_to_security_class(inode->i_mode),
2559
					     qstr, &newsid);
2560 2561 2562 2563
		if (rc) {
			printk(KERN_WARNING "%s:  "
			       "security_transition_sid failed, rc=%d (dev=%s "
			       "ino=%ld)\n",
2564
			       __func__,
2565 2566 2567 2568 2569
			       -rc, inode->i_sb->s_id, inode->i_ino);
			return rc;
		}
	}

2570
	/* Possibly defer initialization to selinux_complete_init. */
2571
	if (sbsec->flags & SE_SBINITIALIZED) {
2572 2573 2574 2575 2576
		struct inode_security_struct *isec = inode->i_security;
		isec->sclass = inode_mode_to_security_class(inode->i_mode);
		isec->sid = newsid;
		isec->initialized = 1;
	}
2577

2578
	if (!ss_initialized || !(sbsec->flags & SE_SBLABELSUPP))
2579 2580
		return -EOPNOTSUPP;

2581
	if (name) {
2582
		namep = kstrdup(XATTR_SELINUX_SUFFIX, GFP_NOFS);
2583 2584 2585 2586
		if (!namep)
			return -ENOMEM;
		*name = namep;
	}
2587

2588
	if (value && len) {
2589
		rc = security_sid_to_context_force(newsid, &context, &clen);
2590 2591 2592 2593 2594 2595
		if (rc) {
			kfree(namep);
			return rc;
		}
		*value = context;
		*len = clen;
2596 2597 2598 2599 2600
	}

	return 0;
}

L
Linus Torvalds 已提交
2601 2602 2603 2604 2605 2606 2607 2608 2609 2610 2611 2612 2613 2614 2615 2616 2617 2618 2619 2620 2621 2622 2623 2624 2625 2626 2627 2628 2629 2630 2631 2632 2633 2634 2635 2636
static int selinux_inode_create(struct inode *dir, struct dentry *dentry, int mask)
{
	return may_create(dir, dentry, SECCLASS_FILE);
}

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

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

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

static int selinux_inode_mknod(struct inode *dir, struct dentry *dentry, int mode, dev_t dev)
{
	return may_create(dir, dentry, inode_mode_to_security_class(mode));
}

static int selinux_inode_rename(struct inode *old_inode, struct dentry *old_dentry,
2637
				struct inode *new_inode, struct dentry *new_dentry)
L
Linus Torvalds 已提交
2638 2639 2640 2641 2642 2643
{
	return may_rename(old_inode, old_dentry, new_inode, new_dentry);
}

static int selinux_inode_readlink(struct dentry *dentry)
{
2644 2645
	const struct cred *cred = current_cred();

E
Eric Paris 已提交
2646
	return dentry_has_perm(cred, dentry, FILE__READ);
L
Linus Torvalds 已提交
2647 2648 2649 2650
}

static int selinux_inode_follow_link(struct dentry *dentry, struct nameidata *nameidata)
{
2651
	const struct cred *cred = current_cred();
L
Linus Torvalds 已提交
2652

E
Eric Paris 已提交
2653
	return dentry_has_perm(cred, dentry, FILE__READ);
L
Linus Torvalds 已提交
2654 2655
}

2656
static int selinux_inode_permission(struct inode *inode, int mask)
L
Linus Torvalds 已提交
2657
{
2658
	const struct cred *cred = current_cred();
2659 2660 2661
	struct common_audit_data ad;
	u32 perms;
	bool from_access;
2662
	unsigned flags = mask & MAY_NOT_BLOCK;
L
Linus Torvalds 已提交
2663

2664
	from_access = mask & MAY_ACCESS;
2665 2666
	mask &= (MAY_READ|MAY_WRITE|MAY_EXEC|MAY_APPEND);

2667 2668
	/* No permission to check.  Existence test. */
	if (!mask)
L
Linus Torvalds 已提交
2669 2670
		return 0;

2671 2672
	COMMON_AUDIT_DATA_INIT(&ad, INODE);
	ad.u.inode = inode;
2673 2674 2675 2676 2677 2678

	if (from_access)
		ad.selinux_audit_data.auditdeny |= FILE__AUDIT_ACCESS;

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

2679
	return inode_has_perm(cred, inode, perms, &ad, flags);
L
Linus Torvalds 已提交
2680 2681 2682 2683
}

static int selinux_inode_setattr(struct dentry *dentry, struct iattr *iattr)
{
2684
	const struct cred *cred = current_cred();
2685
	unsigned int ia_valid = iattr->ia_valid;
L
Linus Torvalds 已提交
2686

2687 2688 2689 2690 2691 2692 2693
	/* 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
2694

2695 2696
	if (ia_valid & (ATTR_MODE | ATTR_UID | ATTR_GID |
			ATTR_ATIME_SET | ATTR_MTIME_SET | ATTR_TIMES_SET))
E
Eric Paris 已提交
2697
		return dentry_has_perm(cred, dentry, FILE__SETATTR);
L
Linus Torvalds 已提交
2698

E
Eric Paris 已提交
2699
	return dentry_has_perm(cred, dentry, FILE__WRITE);
L
Linus Torvalds 已提交
2700 2701 2702 2703
}

static int selinux_inode_getattr(struct vfsmount *mnt, struct dentry *dentry)
{
2704
	const struct cred *cred = current_cred();
E
Eric Paris 已提交
2705 2706 2707 2708
	struct path path;

	path.dentry = dentry;
	path.mnt = mnt;
2709

E
Eric Paris 已提交
2710
	return path_has_perm(cred, &path, FILE__GETATTR);
L
Linus Torvalds 已提交
2711 2712
}

2713
static int selinux_inode_setotherxattr(struct dentry *dentry, const char *name)
2714
{
2715 2716
	const struct cred *cred = current_cred();

2717 2718 2719 2720 2721 2722 2723 2724 2725 2726 2727 2728 2729 2730
	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
2731
	return dentry_has_perm(cred, dentry, FILE__SETATTR);
2732 2733
}

2734 2735
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
2736 2737 2738 2739
{
	struct inode *inode = dentry->d_inode;
	struct inode_security_struct *isec = inode->i_security;
	struct superblock_security_struct *sbsec;
2740
	struct common_audit_data ad;
2741
	u32 newsid, sid = current_sid();
L
Linus Torvalds 已提交
2742 2743
	int rc = 0;

2744 2745
	if (strcmp(name, XATTR_NAME_SELINUX))
		return selinux_inode_setotherxattr(dentry, name);
L
Linus Torvalds 已提交
2746 2747

	sbsec = inode->i_sb->s_security;
2748
	if (!(sbsec->flags & SE_SBLABELSUPP))
L
Linus Torvalds 已提交
2749 2750
		return -EOPNOTSUPP;

2751
	if (!inode_owner_or_capable(inode))
L
Linus Torvalds 已提交
2752 2753
		return -EPERM;

2754 2755
	COMMON_AUDIT_DATA_INIT(&ad, DENTRY);
	ad.u.dentry = dentry;
L
Linus Torvalds 已提交
2756

2757
	rc = avc_has_perm(sid, isec->sid, isec->sclass,
L
Linus Torvalds 已提交
2758 2759 2760 2761 2762
			  FILE__RELABELFROM, &ad);
	if (rc)
		return rc;

	rc = security_context_to_sid(value, size, &newsid);
2763 2764 2765 2766 2767
	if (rc == -EINVAL) {
		if (!capable(CAP_MAC_ADMIN))
			return rc;
		rc = security_context_to_sid_force(value, size, &newsid);
	}
L
Linus Torvalds 已提交
2768 2769 2770
	if (rc)
		return rc;

2771
	rc = avc_has_perm(sid, newsid, isec->sclass,
L
Linus Torvalds 已提交
2772 2773 2774 2775
			  FILE__RELABELTO, &ad);
	if (rc)
		return rc;

2776
	rc = security_validate_transition(isec->sid, newsid, sid,
2777
					  isec->sclass);
L
Linus Torvalds 已提交
2778 2779 2780 2781 2782 2783 2784 2785 2786 2787
	if (rc)
		return rc;

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

2788
static void selinux_inode_post_setxattr(struct dentry *dentry, const char *name,
2789
					const void *value, size_t size,
2790
					int flags)
L
Linus Torvalds 已提交
2791 2792 2793 2794 2795 2796 2797 2798 2799 2800 2801
{
	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;
	}

2802
	rc = security_context_to_sid_force(value, size, &newsid);
L
Linus Torvalds 已提交
2803
	if (rc) {
2804 2805 2806
		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
2807 2808 2809 2810 2811 2812 2813
		return;
	}

	isec->sid = newsid;
	return;
}

2814
static int selinux_inode_getxattr(struct dentry *dentry, const char *name)
L
Linus Torvalds 已提交
2815
{
2816 2817
	const struct cred *cred = current_cred();

E
Eric Paris 已提交
2818
	return dentry_has_perm(cred, dentry, FILE__GETATTR);
L
Linus Torvalds 已提交
2819 2820
}

2821
static int selinux_inode_listxattr(struct dentry *dentry)
L
Linus Torvalds 已提交
2822
{
2823 2824
	const struct cred *cred = current_cred();

E
Eric Paris 已提交
2825
	return dentry_has_perm(cred, dentry, FILE__GETATTR);
L
Linus Torvalds 已提交
2826 2827
}

2828
static int selinux_inode_removexattr(struct dentry *dentry, const char *name)
L
Linus Torvalds 已提交
2829
{
2830 2831
	if (strcmp(name, XATTR_NAME_SELINUX))
		return selinux_inode_setotherxattr(dentry, name);
L
Linus Torvalds 已提交
2832 2833 2834 2835 2836 2837

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

2838
/*
2839
 * Copy the inode security context value to the user.
2840 2841 2842
 *
 * Permission check is handled by selinux_inode_getxattr hook.
 */
2843
static int selinux_inode_getsecurity(const struct inode *inode, const char *name, void **buffer, bool alloc)
L
Linus Torvalds 已提交
2844
{
2845 2846 2847
	u32 size;
	int error;
	char *context = NULL;
L
Linus Torvalds 已提交
2848
	struct inode_security_struct *isec = inode->i_security;
2849

2850 2851
	if (strcmp(name, XATTR_SELINUX_SUFFIX))
		return -EOPNOTSUPP;
2852

2853 2854 2855 2856 2857 2858 2859 2860 2861
	/*
	 * 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.
	 */
2862 2863
	error = selinux_capable(current, current_cred(),
				&init_user_ns, CAP_MAC_ADMIN,
2864
				SECURITY_CAP_NOAUDIT);
2865 2866 2867 2868 2869
	if (!error)
		error = security_sid_to_context_force(isec->sid, &context,
						      &size);
	else
		error = security_sid_to_context(isec->sid, &context, &size);
2870 2871 2872 2873 2874 2875 2876 2877 2878 2879
	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
2880 2881 2882
}

static int selinux_inode_setsecurity(struct inode *inode, const char *name,
2883
				     const void *value, size_t size, int flags)
L
Linus Torvalds 已提交
2884 2885 2886 2887 2888 2889 2890 2891 2892 2893 2894
{
	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;

2895
	rc = security_context_to_sid((void *)value, size, &newsid);
L
Linus Torvalds 已提交
2896 2897 2898 2899
	if (rc)
		return rc;

	isec->sid = newsid;
2900
	isec->initialized = 1;
L
Linus Torvalds 已提交
2901 2902 2903 2904 2905 2906 2907 2908 2909 2910 2911
	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;
}

2912 2913 2914 2915 2916 2917
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
2918 2919
/* file security operations */

2920
static int selinux_revalidate_file_permission(struct file *file, int mask)
L
Linus Torvalds 已提交
2921
{
2922
	const struct cred *cred = current_cred();
J
Josef Sipek 已提交
2923
	struct inode *inode = file->f_path.dentry->d_inode;
L
Linus Torvalds 已提交
2924 2925 2926 2927 2928

	/* 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;

2929 2930
	return file_has_perm(cred, file,
			     file_mask_to_av(inode->i_mode, mask));
L
Linus Torvalds 已提交
2931 2932
}

2933 2934
static int selinux_file_permission(struct file *file, int mask)
{
2935 2936 2937 2938 2939
	struct inode *inode = file->f_path.dentry->d_inode;
	struct file_security_struct *fsec = file->f_security;
	struct inode_security_struct *isec = inode->i_security;
	u32 sid = current_sid();

2940
	if (!mask)
2941 2942 2943
		/* No permission to check.  Existence test. */
		return 0;

2944 2945 2946 2947 2948
	if (sid == fsec->sid && fsec->isid == isec->sid &&
	    fsec->pseqno == avc_policy_seqno())
		/* No change since dentry_open check. */
		return 0;

2949 2950 2951
	return selinux_revalidate_file_permission(file, mask);
}

L
Linus Torvalds 已提交
2952 2953 2954 2955 2956 2957 2958 2959 2960 2961 2962 2963 2964
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)
{
2965
	const struct cred *cred = current_cred();
2966
	int error = 0;
L
Linus Torvalds 已提交
2967

2968 2969 2970 2971 2972 2973 2974 2975 2976 2977 2978 2979
	switch (cmd) {
	case FIONREAD:
	/* fall through */
	case FIBMAP:
	/* fall through */
	case FIGETBSZ:
	/* fall through */
	case EXT2_IOC_GETFLAGS:
	/* fall through */
	case EXT2_IOC_GETVERSION:
		error = file_has_perm(cred, file, FILE__GETATTR);
		break;
L
Linus Torvalds 已提交
2980

2981 2982 2983 2984 2985 2986 2987 2988 2989 2990 2991 2992
	case EXT2_IOC_SETFLAGS:
	/* fall through */
	case EXT2_IOC_SETVERSION:
		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
2993

2994 2995 2996
	case KDSKBENT:
	case KDSKBSENT:
		error = task_has_capability(current, cred, CAP_SYS_TTY_CONFIG,
2997
					SECURITY_CAP_AUDIT);
2998 2999 3000 3001 3002 3003 3004 3005 3006
		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
3007 3008
}

3009 3010
static int default_noexec;

L
Linus Torvalds 已提交
3011 3012
static int file_map_prot_check(struct file *file, unsigned long prot, int shared)
{
3013
	const struct cred *cred = current_cred();
D
David Howells 已提交
3014
	int rc = 0;
3015

3016 3017
	if (default_noexec &&
	    (prot & PROT_EXEC) && (!file || (!shared && (prot & PROT_WRITE)))) {
L
Linus Torvalds 已提交
3018 3019 3020 3021 3022
		/*
		 * 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
3023
		rc = cred_has_perm(cred, cred, PROCESS__EXECMEM);
L
Linus Torvalds 已提交
3024
		if (rc)
D
David Howells 已提交
3025
			goto error;
L
Linus Torvalds 已提交
3026 3027 3028 3029 3030 3031 3032 3033 3034 3035 3036 3037 3038
	}

	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;

3039
		return file_has_perm(cred, file, av);
L
Linus Torvalds 已提交
3040
	}
D
David Howells 已提交
3041 3042 3043

error:
	return rc;
L
Linus Torvalds 已提交
3044 3045 3046
}

static int selinux_file_mmap(struct file *file, unsigned long reqprot,
3047 3048
			     unsigned long prot, unsigned long flags,
			     unsigned long addr, unsigned long addr_only)
L
Linus Torvalds 已提交
3049
{
3050
	int rc = 0;
3051
	u32 sid = current_sid();
L
Linus Torvalds 已提交
3052

3053 3054 3055 3056 3057 3058
	/*
	 * 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.
	 */
3059
	if (addr < CONFIG_LSM_MMAP_MIN_ADDR) {
3060 3061
		rc = avc_has_perm(sid, sid, SECCLASS_MEMPROTECT,
				  MEMPROTECT__MMAP_ZERO, NULL);
3062 3063 3064 3065 3066 3067
		if (rc)
			return rc;
	}

	/* do DAC check on address space usage */
	rc = cap_file_mmap(file, reqprot, prot, flags, addr, addr_only);
3068
	if (rc || addr_only)
L
Linus Torvalds 已提交
3069 3070 3071 3072 3073 3074 3075 3076 3077 3078 3079 3080 3081
		return rc;

	if (selinux_checkreqprot)
		prot = reqprot;

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

static int selinux_file_mprotect(struct vm_area_struct *vma,
				 unsigned long reqprot,
				 unsigned long prot)
{
3082
	const struct cred *cred = current_cred();
L
Linus Torvalds 已提交
3083 3084 3085 3086

	if (selinux_checkreqprot)
		prot = reqprot;

3087 3088
	if (default_noexec &&
	    (prot & PROT_EXEC) && !(vma->vm_flags & VM_EXEC)) {
3089
		int rc = 0;
3090 3091
		if (vma->vm_start >= vma->vm_mm->start_brk &&
		    vma->vm_end <= vma->vm_mm->brk) {
D
David Howells 已提交
3092
			rc = cred_has_perm(cred, cred, PROCESS__EXECHEAP);
3093 3094 3095
		} else if (!vma->vm_file &&
			   vma->vm_start <= vma->vm_mm->start_stack &&
			   vma->vm_end >= vma->vm_mm->start_stack) {
3096
			rc = current_has_perm(current, PROCESS__EXECSTACK);
3097 3098 3099 3100 3101 3102 3103 3104
		} 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
3105
			rc = file_has_perm(cred, vma->vm_file, FILE__EXECMOD);
3106
		}
3107 3108 3109
		if (rc)
			return rc;
	}
L
Linus Torvalds 已提交
3110 3111 3112 3113 3114 3115

	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)
{
3116 3117 3118
	const struct cred *cred = current_cred();

	return file_has_perm(cred, file, FILE__LOCK);
L
Linus Torvalds 已提交
3119 3120 3121 3122 3123
}

static int selinux_file_fcntl(struct file *file, unsigned int cmd,
			      unsigned long arg)
{
3124
	const struct cred *cred = current_cred();
L
Linus Torvalds 已提交
3125 3126 3127
	int err = 0;

	switch (cmd) {
3128 3129 3130 3131 3132
	case F_SETFL:
		if (!file->f_path.dentry || !file->f_path.dentry->d_inode) {
			err = -EINVAL;
			break;
		}
L
Linus Torvalds 已提交
3133

3134
		if ((file->f_flags & O_APPEND) && !(arg & O_APPEND)) {
3135
			err = file_has_perm(cred, file, FILE__WRITE);
L
Linus Torvalds 已提交
3136
			break;
3137 3138 3139 3140 3141 3142 3143 3144
		}
		/* fall through */
	case F_SETOWN:
	case F_SETSIG:
	case F_GETFL:
	case F_GETOWN:
	case F_GETSIG:
		/* Just check FD__USE permission */
3145
		err = file_has_perm(cred, file, 0);
3146 3147 3148 3149
		break;
	case F_GETLK:
	case F_SETLK:
	case F_SETLKW:
L
Linus Torvalds 已提交
3150
#if BITS_PER_LONG == 32
3151 3152 3153
	case F_GETLK64:
	case F_SETLK64:
	case F_SETLKW64:
L
Linus Torvalds 已提交
3154
#endif
3155 3156
		if (!file->f_path.dentry || !file->f_path.dentry->d_inode) {
			err = -EINVAL;
L
Linus Torvalds 已提交
3157
			break;
3158
		}
3159
		err = file_has_perm(cred, file, FILE__LOCK);
3160
		break;
L
Linus Torvalds 已提交
3161 3162 3163 3164 3165 3166 3167 3168 3169 3170
	}

	return err;
}

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

	fsec = file->f_security;
3171
	fsec->fown_sid = current_sid();
L
Linus Torvalds 已提交
3172 3173 3174 3175 3176 3177 3178

	return 0;
}

static int selinux_file_send_sigiotask(struct task_struct *tsk,
				       struct fown_struct *fown, int signum)
{
3179
	struct file *file;
3180
	u32 sid = task_sid(tsk);
L
Linus Torvalds 已提交
3181 3182 3183 3184
	u32 perm;
	struct file_security_struct *fsec;

	/* struct fown_struct is never outside the context of a struct file */
3185
	file = container_of(fown, struct file, f_owner);
L
Linus Torvalds 已提交
3186 3187 3188 3189 3190 3191 3192 3193

	fsec = file->f_security;

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

3194
	return avc_has_perm(fsec->fown_sid, sid,
L
Linus Torvalds 已提交
3195 3196 3197 3198 3199
			    SECCLASS_PROCESS, perm, NULL);
}

static int selinux_file_receive(struct file *file)
{
3200 3201 3202
	const struct cred *cred = current_cred();

	return file_has_perm(cred, file, file_to_av(file));
L
Linus Torvalds 已提交
3203 3204
}

3205
static int selinux_dentry_open(struct file *file, const struct cred *cred)
3206 3207 3208 3209
{
	struct file_security_struct *fsec;
	struct inode *inode;
	struct inode_security_struct *isec;
D
David Howells 已提交
3210

3211 3212 3213 3214 3215 3216 3217 3218 3219 3220 3221 3222 3223 3224 3225 3226 3227 3228 3229 3230
	inode = file->f_path.dentry->d_inode;
	fsec = file->f_security;
	isec = inode->i_security;
	/*
	 * Save inode label and policy sequence number
	 * at open-time so that selinux_file_permission
	 * can determine whether revalidation is necessary.
	 * Task label is already saved in the file security
	 * struct as its SID.
	 */
	fsec->isid = isec->sid;
	fsec->pseqno = avc_policy_seqno();
	/*
	 * Since the inode label or policy seqno may have changed
	 * between the selinux_inode_permission check and the saving
	 * of state above, recheck that access is still permitted.
	 * Otherwise, access might never be revalidated against the
	 * new inode label or new policy.
	 * This check is not redundant - do not remove.
	 */
3231
	return inode_has_perm_noadp(cred, inode, open_file_to_av(file), 0);
3232 3233
}

L
Linus Torvalds 已提交
3234 3235 3236 3237
/* task security operations */

static int selinux_task_create(unsigned long clone_flags)
{
3238
	return current_has_perm(current, PROCESS__FORK);
L
Linus Torvalds 已提交
3239 3240
}

3241 3242 3243 3244 3245 3246 3247 3248 3249 3250 3251 3252 3253 3254 3255
/*
 * 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
3256 3257 3258 3259
/*
 * 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
3260
{
D
David Howells 已提交
3261
	struct task_security_struct *tsec = cred->security;
3262

3263 3264 3265 3266 3267
	/*
	 * 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);
3268
	cred->security = (void *) 0x7UL;
D
David Howells 已提交
3269 3270
	kfree(tsec);
}
L
Linus Torvalds 已提交
3271

D
David Howells 已提交
3272 3273 3274 3275 3276 3277 3278 3279
/*
 * 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
3280

D
David Howells 已提交
3281
	old_tsec = old->security;
L
Linus Torvalds 已提交
3282

D
David Howells 已提交
3283 3284 3285
	tsec = kmemdup(old_tsec, sizeof(struct task_security_struct), gfp);
	if (!tsec)
		return -ENOMEM;
L
Linus Torvalds 已提交
3286

D
David Howells 已提交
3287
	new->security = tsec;
L
Linus Torvalds 已提交
3288 3289 3290
	return 0;
}

3291 3292 3293 3294 3295 3296 3297 3298 3299 3300 3301
/*
 * 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;
}

3302 3303 3304 3305 3306 3307 3308 3309 3310 3311 3312 3313 3314 3315 3316 3317 3318 3319 3320 3321 3322 3323 3324 3325 3326 3327 3328 3329 3330 3331 3332 3333 3334 3335 3336 3337 3338 3339 3340 3341 3342
/*
 * 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;
3343
	return ret;
3344 3345
}

3346
static int selinux_kernel_module_request(char *kmod_name)
3347
{
3348 3349 3350 3351 3352 3353 3354 3355 3356 3357
	u32 sid;
	struct common_audit_data ad;

	sid = task_sid(current);

	COMMON_AUDIT_DATA_INIT(&ad, KMOD);
	ad.u.kmod_name = kmod_name;

	return avc_has_perm(sid, SECINITSID_KERNEL, SECCLASS_SYSTEM,
			    SYSTEM__MODULE_REQUEST, &ad);
3358 3359
}

L
Linus Torvalds 已提交
3360 3361
static int selinux_task_setpgid(struct task_struct *p, pid_t pgid)
{
3362
	return current_has_perm(p, PROCESS__SETPGID);
L
Linus Torvalds 已提交
3363 3364 3365 3366
}

static int selinux_task_getpgid(struct task_struct *p)
{
3367
	return current_has_perm(p, PROCESS__GETPGID);
L
Linus Torvalds 已提交
3368 3369 3370 3371
}

static int selinux_task_getsid(struct task_struct *p)
{
3372
	return current_has_perm(p, PROCESS__GETSESSION);
L
Linus Torvalds 已提交
3373 3374
}

3375 3376
static void selinux_task_getsecid(struct task_struct *p, u32 *secid)
{
3377
	*secid = task_sid(p);
3378 3379
}

L
Linus Torvalds 已提交
3380 3381 3382 3383
static int selinux_task_setnice(struct task_struct *p, int nice)
{
	int rc;

3384
	rc = cap_task_setnice(p, nice);
L
Linus Torvalds 已提交
3385 3386 3387
	if (rc)
		return rc;

3388
	return current_has_perm(p, PROCESS__SETSCHED);
L
Linus Torvalds 已提交
3389 3390
}

3391 3392
static int selinux_task_setioprio(struct task_struct *p, int ioprio)
{
3393 3394
	int rc;

3395
	rc = cap_task_setioprio(p, ioprio);
3396 3397 3398
	if (rc)
		return rc;

3399
	return current_has_perm(p, PROCESS__SETSCHED);
3400 3401
}

3402 3403
static int selinux_task_getioprio(struct task_struct *p)
{
3404
	return current_has_perm(p, PROCESS__GETSCHED);
3405 3406
}

3407 3408
static int selinux_task_setrlimit(struct task_struct *p, unsigned int resource,
		struct rlimit *new_rlim)
L
Linus Torvalds 已提交
3409
{
3410
	struct rlimit *old_rlim = p->signal->rlim + resource;
L
Linus Torvalds 已提交
3411 3412 3413 3414

	/* 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
3415
	   upon context transitions.  See selinux_bprm_committing_creds. */
L
Linus Torvalds 已提交
3416
	if (old_rlim->rlim_max != new_rlim->rlim_max)
3417
		return current_has_perm(p, PROCESS__SETRLIMIT);
L
Linus Torvalds 已提交
3418 3419 3420 3421

	return 0;
}

3422
static int selinux_task_setscheduler(struct task_struct *p)
L
Linus Torvalds 已提交
3423
{
3424 3425
	int rc;

3426
	rc = cap_task_setscheduler(p);
3427 3428 3429
	if (rc)
		return rc;

3430
	return current_has_perm(p, PROCESS__SETSCHED);
L
Linus Torvalds 已提交
3431 3432 3433 3434
}

static int selinux_task_getscheduler(struct task_struct *p)
{
3435
	return current_has_perm(p, PROCESS__GETSCHED);
L
Linus Torvalds 已提交
3436 3437
}

3438 3439
static int selinux_task_movememory(struct task_struct *p)
{
3440
	return current_has_perm(p, PROCESS__SETSCHED);
3441 3442
}

3443 3444
static int selinux_task_kill(struct task_struct *p, struct siginfo *info,
				int sig, u32 secid)
L
Linus Torvalds 已提交
3445 3446 3447 3448 3449 3450 3451 3452
{
	u32 perm;
	int rc;

	if (!sig)
		perm = PROCESS__SIGNULL; /* null signal; existence test */
	else
		perm = signal_to_av(sig);
3453
	if (secid)
3454 3455
		rc = avc_has_perm(secid, task_sid(p),
				  SECCLASS_PROCESS, perm, NULL);
3456
	else
3457
		rc = current_has_perm(p, perm);
3458
	return rc;
L
Linus Torvalds 已提交
3459 3460 3461 3462
}

static int selinux_task_wait(struct task_struct *p)
{
3463
	return task_has_perm(p, current, PROCESS__SIGCHLD);
L
Linus Torvalds 已提交
3464 3465 3466 3467 3468 3469
}

static void selinux_task_to_inode(struct task_struct *p,
				  struct inode *inode)
{
	struct inode_security_struct *isec = inode->i_security;
3470
	u32 sid = task_sid(p);
L
Linus Torvalds 已提交
3471

3472
	isec->sid = sid;
L
Linus Torvalds 已提交
3473 3474 3475 3476
	isec->initialized = 1;
}

/* Returns error only if unable to parse addresses */
3477
static int selinux_parse_skb_ipv4(struct sk_buff *skb,
3478
			struct common_audit_data *ad, u8 *proto)
L
Linus Torvalds 已提交
3479 3480 3481 3482
{
	int offset, ihlen, ret = -EINVAL;
	struct iphdr _iph, *ih;

3483
	offset = skb_network_offset(skb);
L
Linus Torvalds 已提交
3484 3485 3486 3487 3488 3489 3490 3491 3492 3493 3494 3495
	ih = skb_header_pointer(skb, offset, sizeof(_iph), &_iph);
	if (ih == NULL)
		goto out;

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

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

3496 3497 3498
	if (proto)
		*proto = ih->protocol;

L
Linus Torvalds 已提交
3499
	switch (ih->protocol) {
3500 3501
	case IPPROTO_TCP: {
		struct tcphdr _tcph, *th;
L
Linus Torvalds 已提交
3502

3503 3504
		if (ntohs(ih->frag_off) & IP_OFFSET)
			break;
L
Linus Torvalds 已提交
3505 3506 3507 3508 3509 3510 3511 3512 3513

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

		ad->u.net.sport = th->source;
		ad->u.net.dport = th->dest;
		break;
3514 3515 3516 3517 3518 3519 3520 3521
	}

	case IPPROTO_UDP: {
		struct udphdr _udph, *uh;

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

L
Linus Torvalds 已提交
3522
		offset += ihlen;
3523
		uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph);
L
Linus Torvalds 已提交
3524
		if (uh == NULL)
3525
			break;
L
Linus Torvalds 已提交
3526

3527 3528 3529 3530
		ad->u.net.sport = uh->source;
		ad->u.net.dport = uh->dest;
		break;
	}
L
Linus Torvalds 已提交
3531

J
James Morris 已提交
3532 3533 3534 3535 3536 3537 3538 3539 3540 3541 3542 3543 3544 3545
	case IPPROTO_DCCP: {
		struct dccp_hdr _dccph, *dh;

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

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

		ad->u.net.sport = dh->dccph_sport;
		ad->u.net.dport = dh->dccph_dport;
		break;
3546
	}
J
James Morris 已提交
3547

3548 3549 3550
	default:
		break;
	}
L
Linus Torvalds 已提交
3551 3552 3553 3554 3555 3556 3557
out:
	return ret;
}

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

/* Returns error only if unable to parse addresses */
3558
static int selinux_parse_skb_ipv6(struct sk_buff *skb,
3559
			struct common_audit_data *ad, u8 *proto)
L
Linus Torvalds 已提交
3560 3561 3562 3563
{
	u8 nexthdr;
	int ret = -EINVAL, offset;
	struct ipv6hdr _ipv6h, *ip6;
3564
	__be16 frag_off;
L
Linus Torvalds 已提交
3565

3566
	offset = skb_network_offset(skb);
L
Linus Torvalds 已提交
3567 3568 3569 3570
	ip6 = skb_header_pointer(skb, offset, sizeof(_ipv6h), &_ipv6h);
	if (ip6 == NULL)
		goto out;

A
Alexey Dobriyan 已提交
3571 3572
	ad->u.net.v6info.saddr = ip6->saddr;
	ad->u.net.v6info.daddr = ip6->daddr;
L
Linus Torvalds 已提交
3573 3574 3575 3576
	ret = 0;

	nexthdr = ip6->nexthdr;
	offset += sizeof(_ipv6h);
3577
	offset = ipv6_skip_exthdr(skb, offset, &nexthdr, &frag_off);
L
Linus Torvalds 已提交
3578 3579 3580
	if (offset < 0)
		goto out;

3581 3582 3583
	if (proto)
		*proto = nexthdr;

L
Linus Torvalds 已提交
3584 3585
	switch (nexthdr) {
	case IPPROTO_TCP: {
3586
		struct tcphdr _tcph, *th;
L
Linus Torvalds 已提交
3587 3588 3589 3590 3591 3592 3593 3594 3595 3596 3597 3598 3599 3600 3601 3602 3603 3604 3605 3606 3607 3608

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

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

	case IPPROTO_UDP: {
		struct udphdr _udph, *uh;

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

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

J
James Morris 已提交
3609 3610 3611 3612 3613 3614 3615 3616 3617 3618
	case IPPROTO_DCCP: {
		struct dccp_hdr _dccph, *dh;

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

		ad->u.net.sport = dh->dccph_sport;
		ad->u.net.dport = dh->dccph_dport;
		break;
3619
	}
J
James Morris 已提交
3620

L
Linus Torvalds 已提交
3621 3622 3623 3624 3625 3626 3627 3628 3629 3630
	/* includes fragments */
	default:
		break;
	}
out:
	return ret;
}

#endif /* IPV6 */

3631
static int selinux_parse_skb(struct sk_buff *skb, struct common_audit_data *ad,
3632
			     char **_addrp, int src, u8 *proto)
L
Linus Torvalds 已提交
3633
{
3634 3635
	char *addrp;
	int ret;
L
Linus Torvalds 已提交
3636 3637 3638

	switch (ad->u.net.family) {
	case PF_INET:
3639
		ret = selinux_parse_skb_ipv4(skb, ad, proto);
3640 3641 3642 3643 3644
		if (ret)
			goto parse_error;
		addrp = (char *)(src ? &ad->u.net.v4info.saddr :
				       &ad->u.net.v4info.daddr);
		goto okay;
L
Linus Torvalds 已提交
3645 3646 3647

#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
	case PF_INET6:
3648
		ret = selinux_parse_skb_ipv6(skb, ad, proto);
3649 3650 3651 3652 3653
		if (ret)
			goto parse_error;
		addrp = (char *)(src ? &ad->u.net.v6info.saddr :
				       &ad->u.net.v6info.daddr);
		goto okay;
L
Linus Torvalds 已提交
3654 3655
#endif	/* IPV6 */
	default:
3656 3657
		addrp = NULL;
		goto okay;
L
Linus Torvalds 已提交
3658 3659
	}

3660 3661 3662 3663
parse_error:
	printk(KERN_WARNING
	       "SELinux: failure in selinux_parse_skb(),"
	       " unable to parse packet\n");
L
Linus Torvalds 已提交
3664
	return ret;
3665 3666 3667 3668 3669

okay:
	if (_addrp)
		*_addrp = addrp;
	return 0;
L
Linus Torvalds 已提交
3670 3671
}

3672
/**
3673
 * selinux_skb_peerlbl_sid - Determine the peer label of a packet
3674
 * @skb: the packet
3675
 * @family: protocol family
3676
 * @sid: the packet's peer label SID
3677 3678
 *
 * Description:
3679 3680 3681 3682 3683 3684
 * 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.
3685 3686
 *
 */
3687
static int selinux_skb_peerlbl_sid(struct sk_buff *skb, u16 family, u32 *sid)
3688
{
3689
	int err;
3690 3691
	u32 xfrm_sid;
	u32 nlbl_sid;
3692
	u32 nlbl_type;
3693 3694

	selinux_skb_xfrm_sid(skb, &xfrm_sid);
3695
	selinux_netlbl_skbuff_getsid(skb, family, &nlbl_type, &nlbl_sid);
3696

3697 3698 3699 3700 3701
	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");
3702
		return -EACCES;
3703
	}
3704 3705

	return 0;
3706 3707
}

L
Linus Torvalds 已提交
3708
/* socket security operations */
3709

3710 3711
static int socket_sockcreate_sid(const struct task_security_struct *tsec,
				 u16 secclass, u32 *socksid)
3712
{
3713 3714 3715 3716 3717 3718 3719
	if (tsec->sockcreate_sid > SECSID_NULL) {
		*socksid = tsec->sockcreate_sid;
		return 0;
	}

	return security_transition_sid(tsec->sid, tsec->sid, secclass, NULL,
				       socksid);
3720 3721
}

3722
static int sock_has_perm(struct task_struct *task, struct sock *sk, u32 perms)
L
Linus Torvalds 已提交
3723
{
3724
	struct sk_security_struct *sksec = sk->sk_security;
3725
	struct common_audit_data ad;
3726
	u32 tsid = task_sid(task);
L
Linus Torvalds 已提交
3727

3728 3729
	if (sksec->sid == SECINITSID_KERNEL)
		return 0;
L
Linus Torvalds 已提交
3730

3731
	COMMON_AUDIT_DATA_INIT(&ad, NET);
3732
	ad.u.net.sk = sk;
L
Linus Torvalds 已提交
3733

3734
	return avc_has_perm(tsid, sksec->sid, sksec->sclass, perms, &ad);
L
Linus Torvalds 已提交
3735 3736 3737 3738 3739
}

static int selinux_socket_create(int family, int type,
				 int protocol, int kern)
{
3740
	const struct task_security_struct *tsec = current_security();
3741
	u32 newsid;
3742
	u16 secclass;
3743
	int rc;
L
Linus Torvalds 已提交
3744 3745

	if (kern)
3746
		return 0;
3747 3748

	secclass = socket_type_to_security_class(family, type, protocol);
3749 3750 3751 3752
	rc = socket_sockcreate_sid(tsec, secclass, &newsid);
	if (rc)
		return rc;

3753
	return avc_has_perm(tsec->sid, newsid, secclass, SOCKET__CREATE, NULL);
L
Linus Torvalds 已提交
3754 3755
}

V
Venkat Yekkirala 已提交
3756 3757
static int selinux_socket_post_create(struct socket *sock, int family,
				      int type, int protocol, int kern)
L
Linus Torvalds 已提交
3758
{
3759
	const struct task_security_struct *tsec = current_security();
3760
	struct inode_security_struct *isec = SOCK_INODE(sock)->i_security;
3761
	struct sk_security_struct *sksec;
3762 3763
	int err = 0;

3764 3765
	isec->sclass = socket_type_to_security_class(family, type, protocol);

3766 3767
	if (kern)
		isec->sid = SECINITSID_KERNEL;
3768 3769 3770 3771 3772
	else {
		err = socket_sockcreate_sid(tsec, isec->sclass, &(isec->sid));
		if (err)
			return err;
	}
3773

L
Linus Torvalds 已提交
3774 3775
	isec->initialized = 1;

3776 3777 3778
	if (sock->sk) {
		sksec = sock->sk->sk_security;
		sksec->sid = isec->sid;
3779
		sksec->sclass = isec->sclass;
3780
		err = selinux_netlbl_socket_post_create(sock->sk, family);
3781 3782
	}

V
Venkat Yekkirala 已提交
3783
	return err;
L
Linus Torvalds 已提交
3784 3785 3786 3787 3788 3789 3790 3791
}

/* 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)
{
3792
	struct sock *sk = sock->sk;
L
Linus Torvalds 已提交
3793 3794 3795
	u16 family;
	int err;

3796
	err = sock_has_perm(current, sk, SOCKET__BIND);
L
Linus Torvalds 已提交
3797 3798 3799 3800 3801
	if (err)
		goto out;

	/*
	 * If PF_INET or PF_INET6, check name_bind permission for the port.
3802 3803
	 * Multiple address binding for SCTP is not supported yet: we just
	 * check the first address now.
L
Linus Torvalds 已提交
3804
	 */
3805
	family = sk->sk_family;
L
Linus Torvalds 已提交
3806 3807
	if (family == PF_INET || family == PF_INET6) {
		char *addrp;
3808
		struct sk_security_struct *sksec = sk->sk_security;
3809
		struct common_audit_data ad;
L
Linus Torvalds 已提交
3810 3811 3812
		struct sockaddr_in *addr4 = NULL;
		struct sockaddr_in6 *addr6 = NULL;
		unsigned short snum;
3813
		u32 sid, node_perm;
L
Linus Torvalds 已提交
3814 3815 3816 3817 3818 3819 3820 3821 3822 3823 3824

		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;
		}

3825 3826 3827 3828 3829 3830
		if (snum) {
			int low, high;

			inet_get_local_port_range(&low, &high);

			if (snum < max(PROT_SOCK, low) || snum > high) {
P
Paul Moore 已提交
3831 3832
				err = sel_netport_sid(sk->sk_protocol,
						      snum, &sid);
3833 3834
				if (err)
					goto out;
3835
				COMMON_AUDIT_DATA_INIT(&ad, NET);
3836 3837
				ad.u.net.sport = htons(snum);
				ad.u.net.family = family;
3838 3839
				err = avc_has_perm(sksec->sid, sid,
						   sksec->sclass,
3840 3841 3842 3843
						   SOCKET__NAME_BIND, &ad);
				if (err)
					goto out;
			}
L
Linus Torvalds 已提交
3844
		}
3845

3846
		switch (sksec->sclass) {
3847
		case SECCLASS_TCP_SOCKET:
L
Linus Torvalds 已提交
3848 3849
			node_perm = TCP_SOCKET__NODE_BIND;
			break;
3850

3851
		case SECCLASS_UDP_SOCKET:
L
Linus Torvalds 已提交
3852 3853
			node_perm = UDP_SOCKET__NODE_BIND;
			break;
J
James Morris 已提交
3854 3855 3856 3857 3858

		case SECCLASS_DCCP_SOCKET:
			node_perm = DCCP_SOCKET__NODE_BIND;
			break;

L
Linus Torvalds 已提交
3859 3860 3861 3862
		default:
			node_perm = RAWIP_SOCKET__NODE_BIND;
			break;
		}
3863

3864
		err = sel_netnode_sid(addrp, family, &sid);
L
Linus Torvalds 已提交
3865 3866
		if (err)
			goto out;
3867

3868
		COMMON_AUDIT_DATA_INIT(&ad, NET);
L
Linus Torvalds 已提交
3869 3870 3871 3872 3873 3874
		ad.u.net.sport = htons(snum);
		ad.u.net.family = family;

		if (family == PF_INET)
			ad.u.net.v4info.saddr = addr4->sin_addr.s_addr;
		else
A
Alexey Dobriyan 已提交
3875
			ad.u.net.v6info.saddr = addr6->sin6_addr;
L
Linus Torvalds 已提交
3876

3877 3878
		err = avc_has_perm(sksec->sid, sid,
				   sksec->sclass, node_perm, &ad);
L
Linus Torvalds 已提交
3879 3880 3881 3882 3883 3884 3885 3886 3887
		if (err)
			goto out;
	}
out:
	return err;
}

static int selinux_socket_connect(struct socket *sock, struct sockaddr *address, int addrlen)
{
3888
	struct sock *sk = sock->sk;
3889
	struct sk_security_struct *sksec = sk->sk_security;
L
Linus Torvalds 已提交
3890 3891
	int err;

3892
	err = sock_has_perm(current, sk, SOCKET__CONNECT);
L
Linus Torvalds 已提交
3893 3894 3895 3896
	if (err)
		return err;

	/*
J
James Morris 已提交
3897
	 * If a TCP or DCCP socket, check name_connect permission for the port.
L
Linus Torvalds 已提交
3898
	 */
3899 3900
	if (sksec->sclass == SECCLASS_TCP_SOCKET ||
	    sksec->sclass == SECCLASS_DCCP_SOCKET) {
3901
		struct common_audit_data ad;
L
Linus Torvalds 已提交
3902 3903 3904
		struct sockaddr_in *addr4 = NULL;
		struct sockaddr_in6 *addr6 = NULL;
		unsigned short snum;
J
James Morris 已提交
3905
		u32 sid, perm;
L
Linus Torvalds 已提交
3906 3907 3908

		if (sk->sk_family == PF_INET) {
			addr4 = (struct sockaddr_in *)address;
3909
			if (addrlen < sizeof(struct sockaddr_in))
L
Linus Torvalds 已提交
3910 3911 3912 3913
				return -EINVAL;
			snum = ntohs(addr4->sin_port);
		} else {
			addr6 = (struct sockaddr_in6 *)address;
3914
			if (addrlen < SIN6_LEN_RFC2133)
L
Linus Torvalds 已提交
3915 3916 3917 3918
				return -EINVAL;
			snum = ntohs(addr6->sin6_port);
		}

P
Paul Moore 已提交
3919
		err = sel_netport_sid(sk->sk_protocol, snum, &sid);
L
Linus Torvalds 已提交
3920 3921 3922
		if (err)
			goto out;

3923
		perm = (sksec->sclass == SECCLASS_TCP_SOCKET) ?
J
James Morris 已提交
3924 3925
		       TCP_SOCKET__NAME_CONNECT : DCCP_SOCKET__NAME_CONNECT;

3926
		COMMON_AUDIT_DATA_INIT(&ad, NET);
L
Linus Torvalds 已提交
3927 3928
		ad.u.net.dport = htons(snum);
		ad.u.net.family = sk->sk_family;
3929
		err = avc_has_perm(sksec->sid, sid, sksec->sclass, perm, &ad);
L
Linus Torvalds 已提交
3930 3931 3932 3933
		if (err)
			goto out;
	}

3934 3935
	err = selinux_netlbl_socket_connect(sk, address);

L
Linus Torvalds 已提交
3936 3937 3938 3939 3940 3941
out:
	return err;
}

static int selinux_socket_listen(struct socket *sock, int backlog)
{
3942
	return sock_has_perm(current, sock->sk, SOCKET__LISTEN);
L
Linus Torvalds 已提交
3943 3944 3945 3946 3947 3948 3949 3950
}

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

3951
	err = sock_has_perm(current, sock->sk, SOCKET__ACCEPT);
L
Linus Torvalds 已提交
3952 3953 3954 3955 3956 3957 3958 3959 3960 3961 3962 3963 3964 3965
	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,
3966
				  int size)
L
Linus Torvalds 已提交
3967
{
3968
	return sock_has_perm(current, sock->sk, SOCKET__WRITE);
L
Linus Torvalds 已提交
3969 3970 3971 3972 3973
}

static int selinux_socket_recvmsg(struct socket *sock, struct msghdr *msg,
				  int size, int flags)
{
3974
	return sock_has_perm(current, sock->sk, SOCKET__READ);
L
Linus Torvalds 已提交
3975 3976 3977 3978
}

static int selinux_socket_getsockname(struct socket *sock)
{
3979
	return sock_has_perm(current, sock->sk, SOCKET__GETATTR);
L
Linus Torvalds 已提交
3980 3981 3982 3983
}

static int selinux_socket_getpeername(struct socket *sock)
{
3984
	return sock_has_perm(current, sock->sk, SOCKET__GETATTR);
L
Linus Torvalds 已提交
3985 3986
}

3987
static int selinux_socket_setsockopt(struct socket *sock, int level, int optname)
L
Linus Torvalds 已提交
3988
{
3989 3990
	int err;

3991
	err = sock_has_perm(current, sock->sk, SOCKET__SETOPT);
3992 3993 3994 3995
	if (err)
		return err;

	return selinux_netlbl_socket_setsockopt(sock, level, optname);
L
Linus Torvalds 已提交
3996 3997 3998 3999 4000
}

static int selinux_socket_getsockopt(struct socket *sock, int level,
				     int optname)
{
4001
	return sock_has_perm(current, sock->sk, SOCKET__GETOPT);
L
Linus Torvalds 已提交
4002 4003 4004 4005
}

static int selinux_socket_shutdown(struct socket *sock, int how)
{
4006
	return sock_has_perm(current, sock->sk, SOCKET__SHUTDOWN);
L
Linus Torvalds 已提交
4007 4008
}

4009 4010
static int selinux_socket_unix_stream_connect(struct sock *sock,
					      struct sock *other,
L
Linus Torvalds 已提交
4011 4012
					      struct sock *newsk)
{
4013 4014
	struct sk_security_struct *sksec_sock = sock->sk_security;
	struct sk_security_struct *sksec_other = other->sk_security;
4015
	struct sk_security_struct *sksec_new = newsk->sk_security;
4016
	struct common_audit_data ad;
L
Linus Torvalds 已提交
4017 4018
	int err;

4019
	COMMON_AUDIT_DATA_INIT(&ad, NET);
4020
	ad.u.net.sk = other;
L
Linus Torvalds 已提交
4021

4022 4023
	err = avc_has_perm(sksec_sock->sid, sksec_other->sid,
			   sksec_other->sclass,
L
Linus Torvalds 已提交
4024 4025 4026 4027 4028
			   UNIX_STREAM_SOCKET__CONNECTTO, &ad);
	if (err)
		return err;

	/* server child socket */
4029 4030 4031 4032 4033
	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;
4034

4035 4036 4037 4038
	/* connecting socket */
	sksec_sock->peer_sid = sksec_new->sid;

	return 0;
L
Linus Torvalds 已提交
4039 4040 4041 4042 4043
}

static int selinux_socket_unix_may_send(struct socket *sock,
					struct socket *other)
{
4044 4045
	struct sk_security_struct *ssec = sock->sk->sk_security;
	struct sk_security_struct *osec = other->sk->sk_security;
4046
	struct common_audit_data ad;
L
Linus Torvalds 已提交
4047

4048
	COMMON_AUDIT_DATA_INIT(&ad, NET);
L
Linus Torvalds 已提交
4049 4050
	ad.u.net.sk = other->sk;

4051 4052
	return avc_has_perm(ssec->sid, osec->sid, osec->sclass, SOCKET__SENDTO,
			    &ad);
L
Linus Torvalds 已提交
4053 4054
}

4055 4056
static int selinux_inet_sys_rcv_skb(int ifindex, char *addrp, u16 family,
				    u32 peer_sid,
4057
				    struct common_audit_data *ad)
4058 4059 4060 4061 4062 4063 4064 4065 4066 4067 4068 4069 4070 4071 4072 4073 4074 4075 4076 4077
{
	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);
}

4078
static int selinux_sock_rcv_skb_compat(struct sock *sk, struct sk_buff *skb,
4079
				       u16 family)
4080
{
4081
	int err = 0;
4082 4083
	struct sk_security_struct *sksec = sk->sk_security;
	u32 sk_sid = sksec->sid;
4084
	struct common_audit_data ad;
4085 4086
	char *addrp;

4087
	COMMON_AUDIT_DATA_INIT(&ad, NET);
4088
	ad.u.net.netif = skb->skb_iif;
4089 4090 4091 4092
	ad.u.net.family = family;
	err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL);
	if (err)
		return err;
L
Linus Torvalds 已提交
4093

4094
	if (selinux_secmark_enabled()) {
4095
		err = avc_has_perm(sk_sid, skb->secmark, SECCLASS_PACKET,
4096
				   PACKET__RECV, &ad);
4097 4098 4099
		if (err)
			return err;
	}
4100

4101 4102 4103 4104
	err = selinux_netlbl_sock_rcv_skb(sksec, skb, family, &ad);
	if (err)
		return err;
	err = selinux_xfrm_sock_rcv_skb(sksec->sid, skb, &ad);
4105

4106 4107 4108 4109 4110
	return err;
}

static int selinux_socket_sock_rcv_skb(struct sock *sk, struct sk_buff *skb)
{
4111
	int err;
4112
	struct sk_security_struct *sksec = sk->sk_security;
4113 4114
	u16 family = sk->sk_family;
	u32 sk_sid = sksec->sid;
4115
	struct common_audit_data ad;
4116
	char *addrp;
4117 4118
	u8 secmark_active;
	u8 peerlbl_active;
4119 4120

	if (family != PF_INET && family != PF_INET6)
4121
		return 0;
4122 4123

	/* Handle mapped IPv4 packets arriving via IPv6 sockets */
A
Al Viro 已提交
4124
	if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
4125 4126
		family = PF_INET;

4127 4128 4129 4130
	/* 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. */
4131
	if (!selinux_policycap_netpeer)
4132 4133 4134 4135 4136 4137 4138
		return selinux_sock_rcv_skb_compat(sk, skb, family);

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

4139
	COMMON_AUDIT_DATA_INIT(&ad, NET);
4140
	ad.u.net.netif = skb->skb_iif;
4141
	ad.u.net.family = family;
4142
	err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL);
4143
	if (err)
4144
		return err;
4145

4146
	if (peerlbl_active) {
4147 4148 4149
		u32 peer_sid;

		err = selinux_skb_peerlbl_sid(skb, family, &peer_sid);
4150 4151
		if (err)
			return err;
4152
		err = selinux_inet_sys_rcv_skb(skb->skb_iif, addrp, family,
4153
					       peer_sid, &ad);
4154 4155
		if (err) {
			selinux_netlbl_err(skb, err, 0);
4156
			return err;
4157
		}
4158 4159
		err = avc_has_perm(sk_sid, peer_sid, SECCLASS_PEER,
				   PEER__RECV, &ad);
4160 4161
		if (err)
			selinux_netlbl_err(skb, err, 0);
4162 4163
	}

4164
	if (secmark_active) {
4165 4166 4167 4168 4169 4170
		err = avc_has_perm(sk_sid, skb->secmark, SECCLASS_PACKET,
				   PACKET__RECV, &ad);
		if (err)
			return err;
	}

4171
	return err;
L
Linus Torvalds 已提交
4172 4173
}

C
Catherine Zhang 已提交
4174 4175
static int selinux_socket_getpeersec_stream(struct socket *sock, char __user *optval,
					    int __user *optlen, unsigned len)
L
Linus Torvalds 已提交
4176 4177 4178 4179
{
	int err = 0;
	char *scontext;
	u32 scontext_len;
4180
	struct sk_security_struct *sksec = sock->sk->sk_security;
4181
	u32 peer_sid = SECSID_NULL;
L
Linus Torvalds 已提交
4182

4183 4184
	if (sksec->sclass == SECCLASS_UNIX_STREAM_SOCKET ||
	    sksec->sclass == SECCLASS_TCP_SOCKET)
4185
		peer_sid = sksec->peer_sid;
4186 4187
	if (peer_sid == SECSID_NULL)
		return -ENOPROTOOPT;
L
Linus Torvalds 已提交
4188

C
Catherine Zhang 已提交
4189
	err = security_sid_to_context(peer_sid, &scontext, &scontext_len);
L
Linus Torvalds 已提交
4190
	if (err)
4191
		return err;
L
Linus Torvalds 已提交
4192 4193 4194 4195 4196 4197 4198 4199 4200 4201 4202 4203 4204 4205 4206 4207

	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;
}

4208
static int selinux_socket_getpeersec_dgram(struct socket *sock, struct sk_buff *skb, u32 *secid)
C
Catherine Zhang 已提交
4209
{
4210
	u32 peer_secid = SECSID_NULL;
4211
	u16 family;
C
Catherine Zhang 已提交
4212

4213 4214 4215 4216 4217
	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)
4218 4219 4220 4221 4222
		family = sock->sk->sk_family;
	else
		goto out;

	if (sock && family == PF_UNIX)
4223
		selinux_inode_getsecid(SOCK_INODE(sock), &peer_secid);
4224
	else if (skb)
4225
		selinux_skb_peerlbl_sid(skb, family, &peer_secid);
C
Catherine Zhang 已提交
4226

4227
out:
4228
	*secid = peer_secid;
4229 4230 4231
	if (peer_secid == SECSID_NULL)
		return -EINVAL;
	return 0;
C
Catherine Zhang 已提交
4232 4233
}

A
Al Viro 已提交
4234
static int selinux_sk_alloc_security(struct sock *sk, int family, gfp_t priority)
L
Linus Torvalds 已提交
4235
{
4236 4237 4238 4239 4240 4241 4242 4243 4244 4245 4246 4247
	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
4248 4249 4250 4251
}

static void selinux_sk_free_security(struct sock *sk)
{
4252 4253 4254 4255 4256
	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
4257 4258
}

4259
static void selinux_sk_clone_security(const struct sock *sk, struct sock *newsk)
4260
{
4261 4262
	struct sk_security_struct *sksec = sk->sk_security;
	struct sk_security_struct *newsksec = newsk->sk_security;
4263

4264 4265 4266
	newsksec->sid = sksec->sid;
	newsksec->peer_sid = sksec->peer_sid;
	newsksec->sclass = sksec->sclass;
4267

4268
	selinux_netlbl_sk_security_reset(newsksec);
4269 4270
}

V
Venkat Yekkirala 已提交
4271
static void selinux_sk_getsecid(struct sock *sk, u32 *secid)
4272
{
4273
	if (!sk)
V
Venkat Yekkirala 已提交
4274
		*secid = SECINITSID_ANY_SOCKET;
4275 4276
	else {
		struct sk_security_struct *sksec = sk->sk_security;
4277

V
Venkat Yekkirala 已提交
4278
		*secid = sksec->sid;
4279
	}
4280 4281
}

4282
static void selinux_sock_graft(struct sock *sk, struct socket *parent)
4283 4284 4285 4286
{
	struct inode_security_struct *isec = SOCK_INODE(parent)->i_security;
	struct sk_security_struct *sksec = sk->sk_security;

4287 4288 4289
	if (sk->sk_family == PF_INET || sk->sk_family == PF_INET6 ||
	    sk->sk_family == PF_UNIX)
		isec->sid = sksec->sid;
4290
	sksec->sclass = isec->sclass;
4291 4292
}

4293 4294
static int selinux_inet_conn_request(struct sock *sk, struct sk_buff *skb,
				     struct request_sock *req)
4295 4296 4297
{
	struct sk_security_struct *sksec = sk->sk_security;
	int err;
4298
	u16 family = sk->sk_family;
V
Venkat Yekkirala 已提交
4299
	u32 newsid;
4300 4301
	u32 peersid;

4302 4303 4304 4305 4306
	/* handle mapped IPv4 packets arriving via IPv6 sockets */
	if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
		family = PF_INET;

	err = selinux_skb_peerlbl_sid(skb, family, &peersid);
4307 4308
	if (err)
		return err;
4309 4310
	if (peersid == SECSID_NULL) {
		req->secid = sksec->sid;
4311
		req->peer_secid = SECSID_NULL;
4312 4313 4314 4315 4316 4317
	} else {
		err = security_sid_mls_copy(sksec->sid, peersid, &newsid);
		if (err)
			return err;
		req->secid = newsid;
		req->peer_secid = peersid;
4318 4319
	}

4320
	return selinux_netlbl_inet_conn_request(req, family);
4321 4322
}

4323 4324
static void selinux_inet_csk_clone(struct sock *newsk,
				   const struct request_sock *req)
4325 4326 4327 4328
{
	struct sk_security_struct *newsksec = newsk->sk_security;

	newsksec->sid = req->secid;
4329
	newsksec->peer_sid = req->peer_secid;
4330 4331 4332 4333
	/* 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. */
4334

P
Paul Moore 已提交
4335 4336
	/* We don't need to take any sort of lock here as we are the only
	 * thread with access to newsksec */
4337
	selinux_netlbl_inet_csk_clone(newsk, req->rsk_ops->family);
4338 4339
}

4340
static void selinux_inet_conn_established(struct sock *sk, struct sk_buff *skb)
4341
{
4342
	u16 family = sk->sk_family;
4343 4344
	struct sk_security_struct *sksec = sk->sk_security;

4345 4346 4347 4348 4349
	/* 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);
4350 4351
}

4352 4353 4354 4355 4356 4357 4358 4359 4360 4361 4362 4363 4364 4365 4366 4367 4368 4369 4370 4371 4372
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);
}

4373 4374
static void selinux_req_classify_flow(const struct request_sock *req,
				      struct flowi *fl)
4375
{
4376
	fl->flowi_secid = req->secid;
4377 4378
}

4379 4380 4381 4382 4383 4384 4385 4386 4387 4388 4389 4390 4391 4392 4393 4394 4395 4396 4397 4398 4399 4400 4401 4402 4403 4404 4405 4406 4407 4408 4409 4410 4411 4412 4413 4414 4415 4416 4417 4418 4419 4420 4421 4422 4423 4424 4425 4426 4427 4428 4429 4430 4431
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);
}

static void selinux_tun_dev_post_create(struct sock *sk)
{
	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 */

	/* see the comments in selinux_tun_dev_create() about why we don't use
	 * the sockcreate SID here */

	sksec->sid = current_sid();
	sksec->sclass = SECCLASS_TUN_SOCKET;
}

static int selinux_tun_dev_attach(struct sock *sk)
{
	struct sk_security_struct *sksec = sk->sk_security;
	u32 sid = current_sid();
	int err;

	err = avc_has_perm(sid, sksec->sid, SECCLASS_TUN_SOCKET,
			   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;

	sksec->sid = sid;

	return 0;
}

L
Linus Torvalds 已提交
4432 4433 4434 4435 4436
static int selinux_nlmsg_perm(struct sock *sk, struct sk_buff *skb)
{
	int err = 0;
	u32 perm;
	struct nlmsghdr *nlh;
4437
	struct sk_security_struct *sksec = sk->sk_security;
4438

L
Linus Torvalds 已提交
4439 4440 4441 4442
	if (skb->len < NLMSG_SPACE(0)) {
		err = -EINVAL;
		goto out;
	}
4443
	nlh = nlmsg_hdr(skb);
4444

4445
	err = selinux_nlmsg_lookup(sksec->sclass, nlh->nlmsg_type, &perm);
L
Linus Torvalds 已提交
4446 4447
	if (err) {
		if (err == -EINVAL) {
4448
			audit_log(current->audit_context, GFP_KERNEL, AUDIT_SELINUX_ERR,
L
Linus Torvalds 已提交
4449 4450
				  "SELinux:  unrecognized netlink message"
				  " type=%hu for sclass=%hu\n",
4451
				  nlh->nlmsg_type, sksec->sclass);
4452
			if (!selinux_enforcing || security_get_allow_unknown())
L
Linus Torvalds 已提交
4453 4454 4455 4456 4457 4458 4459 4460 4461
				err = 0;
		}

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

4462
	err = sock_has_perm(current, sk, perm);
L
Linus Torvalds 已提交
4463 4464 4465 4466 4467 4468
out:
	return err;
}

#ifdef CONFIG_NETFILTER

4469 4470
static unsigned int selinux_ip_forward(struct sk_buff *skb, int ifindex,
				       u16 family)
L
Linus Torvalds 已提交
4471
{
4472
	int err;
4473 4474
	char *addrp;
	u32 peer_sid;
4475
	struct common_audit_data ad;
4476
	u8 secmark_active;
4477
	u8 netlbl_active;
4478
	u8 peerlbl_active;
4479

4480 4481
	if (!selinux_policycap_netpeer)
		return NF_ACCEPT;
4482

4483
	secmark_active = selinux_secmark_enabled();
4484 4485
	netlbl_active = netlbl_enabled();
	peerlbl_active = netlbl_active || selinux_xfrm_enabled();
4486 4487
	if (!secmark_active && !peerlbl_active)
		return NF_ACCEPT;
4488

4489 4490 4491
	if (selinux_skb_peerlbl_sid(skb, family, &peer_sid) != 0)
		return NF_DROP;

4492
	COMMON_AUDIT_DATA_INIT(&ad, NET);
4493 4494 4495 4496 4497
	ad.u.net.netif = ifindex;
	ad.u.net.family = family;
	if (selinux_parse_skb(skb, &ad, &addrp, 1, NULL) != 0)
		return NF_DROP;

4498 4499 4500 4501 4502
	if (peerlbl_active) {
		err = selinux_inet_sys_rcv_skb(ifindex, addrp, family,
					       peer_sid, &ad);
		if (err) {
			selinux_netlbl_err(skb, err, 1);
4503
			return NF_DROP;
4504 4505
		}
	}
4506 4507 4508 4509 4510 4511

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

4512 4513 4514 4515 4516 4517 4518 4519
	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;

4520 4521 4522 4523 4524 4525 4526 4527 4528 4529 4530 4531 4532 4533 4534 4535 4536 4537 4538 4539 4540 4541 4542
	return NF_ACCEPT;
}

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

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

4543 4544 4545 4546 4547 4548 4549 4550 4551 4552 4553 4554 4555 4556 4557 4558 4559 4560 4561 4562 4563 4564 4565 4566 4567 4568 4569 4570 4571 4572 4573
static unsigned int selinux_ip_output(struct sk_buff *skb,
				      u16 family)
{
	u32 sid;

	if (!netlbl_enabled())
		return NF_ACCEPT;

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

	return NF_ACCEPT;
}

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

4574 4575
static unsigned int selinux_ip_postroute_compat(struct sk_buff *skb,
						int ifindex,
4576
						u16 family)
4577 4578 4579
{
	struct sock *sk = skb->sk;
	struct sk_security_struct *sksec;
4580
	struct common_audit_data ad;
4581 4582
	char *addrp;
	u8 proto;
L
Linus Torvalds 已提交
4583

4584 4585 4586 4587
	if (sk == NULL)
		return NF_ACCEPT;
	sksec = sk->sk_security;

4588
	COMMON_AUDIT_DATA_INIT(&ad, NET);
4589 4590 4591 4592 4593
	ad.u.net.netif = ifindex;
	ad.u.net.family = family;
	if (selinux_parse_skb(skb, &ad, &addrp, 0, &proto))
		return NF_DROP;

4594
	if (selinux_secmark_enabled())
4595
		if (avc_has_perm(sksec->sid, skb->secmark,
4596
				 SECCLASS_PACKET, PACKET__SEND, &ad))
4597
			return NF_DROP_ERR(-ECONNREFUSED);
4598

4599 4600
	if (selinux_xfrm_postroute_last(sksec->sid, skb, &ad, proto))
		return NF_DROP_ERR(-ECONNREFUSED);
4601 4602

	return NF_ACCEPT;
4603 4604
}

4605 4606
static unsigned int selinux_ip_postroute(struct sk_buff *skb, int ifindex,
					 u16 family)
4607
{
4608 4609
	u32 secmark_perm;
	u32 peer_sid;
4610
	struct sock *sk;
4611
	struct common_audit_data ad;
4612 4613 4614
	char *addrp;
	u8 secmark_active;
	u8 peerlbl_active;
4615

4616 4617 4618 4619
	/* 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. */
4620
	if (!selinux_policycap_netpeer)
4621
		return selinux_ip_postroute_compat(skb, ifindex, family);
4622
#ifdef CONFIG_XFRM
4623 4624 4625 4626 4627 4628
	/* If skb->dst->xfrm is non-NULL then the packet is undergoing an IPsec
	 * packet transformation so allow the packet to pass without any checks
	 * since we'll have another chance to perform access control checks
	 * when the packet is on it's final way out.
	 * NOTE: there appear to be some IPv6 multicast cases where skb->dst
	 *       is NULL, in this case go ahead and apply access control. */
E
Eric Dumazet 已提交
4629
	if (skb_dst(skb) != NULL && skb_dst(skb)->xfrm != NULL)
4630
		return NF_ACCEPT;
4631
#endif
4632 4633 4634 4635 4636
	secmark_active = selinux_secmark_enabled();
	peerlbl_active = netlbl_enabled() || selinux_xfrm_enabled();
	if (!secmark_active && !peerlbl_active)
		return NF_ACCEPT;

4637 4638 4639 4640
	/* if the packet is being forwarded then get the peer label from the
	 * packet itself; otherwise check to see if it is from a local
	 * application or the kernel, if from an application get the peer label
	 * from the sending socket, otherwise use the kernel's sid */
4641
	sk = skb->sk;
4642
	if (sk == NULL) {
4643 4644
		if (skb->skb_iif) {
			secmark_perm = PACKET__FORWARD_OUT;
4645
			if (selinux_skb_peerlbl_sid(skb, family, &peer_sid))
4646
				return NF_DROP;
4647 4648
		} else {
			secmark_perm = PACKET__SEND;
4649
			peer_sid = SECINITSID_KERNEL;
4650
		}
4651
	} else {
4652 4653 4654 4655
		struct sk_security_struct *sksec = sk->sk_security;
		peer_sid = sksec->sid;
		secmark_perm = PACKET__SEND;
	}
4656

4657
	COMMON_AUDIT_DATA_INIT(&ad, NET);
4658 4659 4660
	ad.u.net.netif = ifindex;
	ad.u.net.family = family;
	if (selinux_parse_skb(skb, &ad, &addrp, 0, NULL))
4661
		return NF_DROP;
4662

4663 4664 4665
	if (secmark_active)
		if (avc_has_perm(peer_sid, skb->secmark,
				 SECCLASS_PACKET, secmark_perm, &ad))
4666
			return NF_DROP_ERR(-ECONNREFUSED);
4667 4668 4669 4670 4671 4672

	if (peerlbl_active) {
		u32 if_sid;
		u32 node_sid;

		if (sel_netif_sid(ifindex, &if_sid))
4673
			return NF_DROP;
4674 4675
		if (avc_has_perm(peer_sid, if_sid,
				 SECCLASS_NETIF, NETIF__EGRESS, &ad))
4676
			return NF_DROP_ERR(-ECONNREFUSED);
4677 4678

		if (sel_netnode_sid(addrp, family, &node_sid))
4679
			return NF_DROP;
4680 4681
		if (avc_has_perm(peer_sid, node_sid,
				 SECCLASS_NODE, NODE__SENDTO, &ad))
4682
			return NF_DROP_ERR(-ECONNREFUSED);
4683
	}
4684

4685
	return NF_ACCEPT;
L
Linus Torvalds 已提交
4686 4687
}

4688 4689 4690 4691 4692
static unsigned int selinux_ipv4_postroute(unsigned int hooknum,
					   struct sk_buff *skb,
					   const struct net_device *in,
					   const struct net_device *out,
					   int (*okfn)(struct sk_buff *))
L
Linus Torvalds 已提交
4693
{
4694
	return selinux_ip_postroute(skb, out->ifindex, PF_INET);
L
Linus Torvalds 已提交
4695 4696 4697
}

#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
4698 4699 4700 4701 4702
static unsigned int selinux_ipv6_postroute(unsigned int hooknum,
					   struct sk_buff *skb,
					   const struct net_device *in,
					   const struct net_device *out,
					   int (*okfn)(struct sk_buff *))
L
Linus Torvalds 已提交
4703
{
4704
	return selinux_ip_postroute(skb, out->ifindex, PF_INET6);
L
Linus Torvalds 已提交
4705 4706 4707 4708 4709 4710 4711 4712 4713
}
#endif	/* IPV6 */

#endif	/* CONFIG_NETFILTER */

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

4714
	err = cap_netlink_send(sk, skb);
L
Linus Torvalds 已提交
4715 4716 4717
	if (err)
		return err;

4718
	return selinux_nlmsg_perm(sk, skb);
L
Linus Torvalds 已提交
4719 4720
}

4721
static int selinux_netlink_recv(struct sk_buff *skb, int capability)
L
Linus Torvalds 已提交
4722
{
4723
	int err;
4724
	struct common_audit_data ad;
4725
	u32 sid;
4726

4727
	err = cap_netlink_recv(skb, capability);
4728 4729 4730
	if (err)
		return err;

4731
	COMMON_AUDIT_DATA_INIT(&ad, CAP);
4732 4733
	ad.u.cap = capability;

4734 4735 4736
	security_task_getsecid(current, &sid);
	return avc_has_perm(sid, sid, SECCLASS_CAPABILITY,
			    CAP_TO_MASK(capability), &ad);
L
Linus Torvalds 已提交
4737 4738 4739 4740 4741 4742 4743
}

static int ipc_alloc_security(struct task_struct *task,
			      struct kern_ipc_perm *perm,
			      u16 sclass)
{
	struct ipc_security_struct *isec;
4744
	u32 sid;
L
Linus Torvalds 已提交
4745

J
James Morris 已提交
4746
	isec = kzalloc(sizeof(struct ipc_security_struct), GFP_KERNEL);
L
Linus Torvalds 已提交
4747 4748 4749
	if (!isec)
		return -ENOMEM;

4750
	sid = task_sid(task);
L
Linus Torvalds 已提交
4751
	isec->sclass = sclass;
4752
	isec->sid = sid;
L
Linus Torvalds 已提交
4753 4754 4755 4756 4757 4758 4759 4760 4761 4762 4763 4764 4765 4766 4767 4768
	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
4769
	msec = kzalloc(sizeof(struct msg_security_struct), GFP_KERNEL);
L
Linus Torvalds 已提交
4770 4771 4772 4773 4774 4775 4776 4777 4778 4779 4780 4781 4782 4783 4784 4785 4786 4787
	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,
4788
			u32 perms)
L
Linus Torvalds 已提交
4789 4790
{
	struct ipc_security_struct *isec;
4791
	struct common_audit_data ad;
4792
	u32 sid = current_sid();
L
Linus Torvalds 已提交
4793 4794 4795

	isec = ipc_perms->security;

4796
	COMMON_AUDIT_DATA_INIT(&ad, IPC);
L
Linus Torvalds 已提交
4797 4798
	ad.u.ipc_id = ipc_perms->key;

4799
	return avc_has_perm(sid, isec->sid, isec->sclass, perms, &ad);
L
Linus Torvalds 已提交
4800 4801 4802 4803 4804 4805 4806 4807 4808 4809 4810 4811 4812 4813 4814 4815
}

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;
4816
	struct common_audit_data ad;
4817
	u32 sid = current_sid();
L
Linus Torvalds 已提交
4818 4819 4820 4821 4822 4823 4824 4825
	int rc;

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

	isec = msq->q_perm.security;

4826
	COMMON_AUDIT_DATA_INIT(&ad, IPC);
4827
	ad.u.ipc_id = msq->q_perm.key;
L
Linus Torvalds 已提交
4828

4829
	rc = avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
L
Linus Torvalds 已提交
4830 4831 4832 4833 4834 4835 4836 4837 4838 4839 4840 4841 4842 4843 4844 4845
			  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;
4846
	struct common_audit_data ad;
4847
	u32 sid = current_sid();
L
Linus Torvalds 已提交
4848 4849 4850

	isec = msq->q_perm.security;

4851
	COMMON_AUDIT_DATA_INIT(&ad, IPC);
L
Linus Torvalds 已提交
4852 4853
	ad.u.ipc_id = msq->q_perm.key;

4854
	return avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
L
Linus Torvalds 已提交
4855 4856 4857 4858 4859 4860 4861 4862
			    MSGQ__ASSOCIATE, &ad);
}

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

4863
	switch (cmd) {
L
Linus Torvalds 已提交
4864 4865 4866 4867 4868 4869 4870 4871 4872 4873 4874 4875 4876 4877 4878 4879 4880 4881
	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;
	}

4882
	err = ipc_has_perm(&msq->q_perm, perms);
L
Linus Torvalds 已提交
4883 4884 4885 4886 4887 4888 4889
	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;
4890
	struct common_audit_data ad;
4891
	u32 sid = current_sid();
L
Linus Torvalds 已提交
4892 4893 4894 4895 4896 4897 4898 4899 4900 4901 4902 4903 4904
	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
		 */
4905
		rc = security_transition_sid(sid, isec->sid, SECCLASS_MSG,
4906
					     NULL, &msec->sid);
L
Linus Torvalds 已提交
4907 4908 4909 4910
		if (rc)
			return rc;
	}

4911
	COMMON_AUDIT_DATA_INIT(&ad, IPC);
L
Linus Torvalds 已提交
4912 4913 4914
	ad.u.ipc_id = msq->q_perm.key;

	/* Can this process write to the queue? */
4915
	rc = avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
L
Linus Torvalds 已提交
4916 4917 4918
			  MSGQ__WRITE, &ad);
	if (!rc)
		/* Can this process send the message */
4919 4920
		rc = avc_has_perm(sid, msec->sid, SECCLASS_MSG,
				  MSG__SEND, &ad);
L
Linus Torvalds 已提交
4921 4922
	if (!rc)
		/* Can the message be put in the queue? */
4923 4924
		rc = avc_has_perm(msec->sid, isec->sid, SECCLASS_MSGQ,
				  MSGQ__ENQUEUE, &ad);
L
Linus Torvalds 已提交
4925 4926 4927 4928 4929 4930 4931 4932 4933 4934

	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;
4935
	struct common_audit_data ad;
4936
	u32 sid = task_sid(target);
L
Linus Torvalds 已提交
4937 4938 4939 4940 4941
	int rc;

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

4942
	COMMON_AUDIT_DATA_INIT(&ad, IPC);
4943
	ad.u.ipc_id = msq->q_perm.key;
L
Linus Torvalds 已提交
4944

4945
	rc = avc_has_perm(sid, isec->sid,
L
Linus Torvalds 已提交
4946 4947
			  SECCLASS_MSGQ, MSGQ__READ, &ad);
	if (!rc)
4948
		rc = avc_has_perm(sid, msec->sid,
L
Linus Torvalds 已提交
4949 4950 4951 4952 4953 4954 4955 4956
				  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;
4957
	struct common_audit_data ad;
4958
	u32 sid = current_sid();
L
Linus Torvalds 已提交
4959 4960 4961 4962 4963 4964 4965 4966
	int rc;

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

	isec = shp->shm_perm.security;

4967
	COMMON_AUDIT_DATA_INIT(&ad, IPC);
4968
	ad.u.ipc_id = shp->shm_perm.key;
L
Linus Torvalds 已提交
4969

4970
	rc = avc_has_perm(sid, isec->sid, SECCLASS_SHM,
L
Linus Torvalds 已提交
4971 4972 4973 4974 4975 4976 4977 4978 4979 4980 4981 4982 4983 4984 4985 4986
			  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;
4987
	struct common_audit_data ad;
4988
	u32 sid = current_sid();
L
Linus Torvalds 已提交
4989 4990 4991

	isec = shp->shm_perm.security;

4992
	COMMON_AUDIT_DATA_INIT(&ad, IPC);
L
Linus Torvalds 已提交
4993 4994
	ad.u.ipc_id = shp->shm_perm.key;

4995
	return avc_has_perm(sid, isec->sid, SECCLASS_SHM,
L
Linus Torvalds 已提交
4996 4997 4998 4999 5000 5001 5002 5003 5004
			    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;

5005
	switch (cmd) {
L
Linus Torvalds 已提交
5006 5007 5008 5009 5010 5011 5012 5013 5014 5015 5016 5017 5018 5019 5020 5021 5022 5023 5024 5025 5026 5027
	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;
	}

5028
	err = ipc_has_perm(&shp->shm_perm, perms);
L
Linus Torvalds 已提交
5029 5030 5031 5032 5033 5034 5035 5036 5037 5038 5039 5040 5041
	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;

5042
	return ipc_has_perm(&shp->shm_perm, perms);
L
Linus Torvalds 已提交
5043 5044 5045 5046 5047 5048
}

/* Semaphore security operations */
static int selinux_sem_alloc_security(struct sem_array *sma)
{
	struct ipc_security_struct *isec;
5049
	struct common_audit_data ad;
5050
	u32 sid = current_sid();
L
Linus Torvalds 已提交
5051 5052 5053 5054 5055 5056 5057 5058
	int rc;

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

	isec = sma->sem_perm.security;

5059
	COMMON_AUDIT_DATA_INIT(&ad, IPC);
5060
	ad.u.ipc_id = sma->sem_perm.key;
L
Linus Torvalds 已提交
5061

5062
	rc = avc_has_perm(sid, isec->sid, SECCLASS_SEM,
L
Linus Torvalds 已提交
5063 5064 5065 5066 5067 5068 5069 5070 5071 5072 5073 5074 5075 5076 5077 5078
			  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;
5079
	struct common_audit_data ad;
5080
	u32 sid = current_sid();
L
Linus Torvalds 已提交
5081 5082 5083

	isec = sma->sem_perm.security;

5084
	COMMON_AUDIT_DATA_INIT(&ad, IPC);
L
Linus Torvalds 已提交
5085 5086
	ad.u.ipc_id = sma->sem_perm.key;

5087
	return avc_has_perm(sid, isec->sid, SECCLASS_SEM,
L
Linus Torvalds 已提交
5088 5089 5090 5091 5092 5093 5094 5095 5096
			    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;

5097
	switch (cmd) {
L
Linus Torvalds 已提交
5098 5099 5100 5101 5102 5103 5104 5105 5106 5107 5108 5109 5110 5111 5112 5113 5114 5115 5116 5117 5118 5119 5120 5121 5122 5123 5124 5125 5126 5127 5128
	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;
	}

5129
	err = ipc_has_perm(&sma->sem_perm, perms);
L
Linus Torvalds 已提交
5130 5131 5132 5133 5134 5135 5136 5137 5138 5139 5140 5141 5142
	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;

5143
	return ipc_has_perm(&sma->sem_perm, perms);
L
Linus Torvalds 已提交
5144 5145 5146 5147 5148 5149 5150 5151 5152 5153 5154 5155 5156 5157 5158
}

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;

5159
	return ipc_has_perm(ipcp, av);
L
Linus Torvalds 已提交
5160 5161
}

5162 5163 5164 5165 5166 5167
static void selinux_ipc_getsecid(struct kern_ipc_perm *ipcp, u32 *secid)
{
	struct ipc_security_struct *isec = ipcp->security;
	*secid = isec->sid;
}

5168
static void selinux_d_instantiate(struct dentry *dentry, struct inode *inode)
L
Linus Torvalds 已提交
5169 5170 5171 5172 5173 5174
{
	if (inode)
		inode_doinit_with_dentry(inode, dentry);
}

static int selinux_getprocattr(struct task_struct *p,
5175
			       char *name, char **value)
L
Linus Torvalds 已提交
5176
{
5177
	const struct task_security_struct *__tsec;
5178
	u32 sid;
L
Linus Torvalds 已提交
5179
	int error;
5180
	unsigned len;
L
Linus Torvalds 已提交
5181 5182

	if (current != p) {
5183
		error = current_has_perm(p, PROCESS__GETATTR);
L
Linus Torvalds 已提交
5184 5185 5186 5187
		if (error)
			return error;
	}

5188 5189
	rcu_read_lock();
	__tsec = __task_cred(p)->security;
L
Linus Torvalds 已提交
5190 5191

	if (!strcmp(name, "current"))
5192
		sid = __tsec->sid;
L
Linus Torvalds 已提交
5193
	else if (!strcmp(name, "prev"))
5194
		sid = __tsec->osid;
L
Linus Torvalds 已提交
5195
	else if (!strcmp(name, "exec"))
5196
		sid = __tsec->exec_sid;
L
Linus Torvalds 已提交
5197
	else if (!strcmp(name, "fscreate"))
5198
		sid = __tsec->create_sid;
5199
	else if (!strcmp(name, "keycreate"))
5200
		sid = __tsec->keycreate_sid;
5201
	else if (!strcmp(name, "sockcreate"))
5202
		sid = __tsec->sockcreate_sid;
L
Linus Torvalds 已提交
5203
	else
5204 5205
		goto invalid;
	rcu_read_unlock();
L
Linus Torvalds 已提交
5206 5207 5208 5209

	if (!sid)
		return 0;

5210 5211 5212 5213
	error = security_sid_to_context(sid, value, &len);
	if (error)
		return error;
	return len;
5214 5215 5216 5217

invalid:
	rcu_read_unlock();
	return -EINVAL;
L
Linus Torvalds 已提交
5218 5219 5220 5221 5222 5223
}

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
5224
	struct task_struct *tracer;
D
David Howells 已提交
5225 5226
	struct cred *new;
	u32 sid = 0, ptsid;
L
Linus Torvalds 已提交
5227 5228 5229 5230 5231 5232 5233 5234 5235 5236 5237 5238 5239 5240 5241
	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"))
5242
		error = current_has_perm(p, PROCESS__SETEXEC);
L
Linus Torvalds 已提交
5243
	else if (!strcmp(name, "fscreate"))
5244
		error = current_has_perm(p, PROCESS__SETFSCREATE);
5245
	else if (!strcmp(name, "keycreate"))
5246
		error = current_has_perm(p, PROCESS__SETKEYCREATE);
5247
	else if (!strcmp(name, "sockcreate"))
5248
		error = current_has_perm(p, PROCESS__SETSOCKCREATE);
L
Linus Torvalds 已提交
5249
	else if (!strcmp(name, "current"))
5250
		error = current_has_perm(p, PROCESS__SETCURRENT);
L
Linus Torvalds 已提交
5251 5252 5253 5254 5255 5256 5257 5258 5259 5260 5261 5262
	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);
5263 5264 5265 5266 5267 5268
		if (error == -EINVAL && !strcmp(name, "fscreate")) {
			if (!capable(CAP_MAC_ADMIN))
				return error;
			error = security_context_to_sid_force(value, size,
							      &sid);
		}
L
Linus Torvalds 已提交
5269 5270 5271 5272
		if (error)
			return error;
	}

D
David Howells 已提交
5273 5274 5275 5276
	new = prepare_creds();
	if (!new)
		return -ENOMEM;

L
Linus Torvalds 已提交
5277 5278 5279
	/* 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
5280
	   operation.  See selinux_bprm_set_creds for the execve
L
Linus Torvalds 已提交
5281 5282
	   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
5283 5284
	tsec = new->security;
	if (!strcmp(name, "exec")) {
L
Linus Torvalds 已提交
5285
		tsec->exec_sid = sid;
D
David Howells 已提交
5286
	} else if (!strcmp(name, "fscreate")) {
L
Linus Torvalds 已提交
5287
		tsec->create_sid = sid;
D
David Howells 已提交
5288
	} else if (!strcmp(name, "keycreate")) {
5289 5290
		error = may_create_key(sid, p);
		if (error)
D
David Howells 已提交
5291
			goto abort_change;
5292
		tsec->keycreate_sid = sid;
D
David Howells 已提交
5293
	} else if (!strcmp(name, "sockcreate")) {
5294
		tsec->sockcreate_sid = sid;
D
David Howells 已提交
5295 5296
	} else if (!strcmp(name, "current")) {
		error = -EINVAL;
L
Linus Torvalds 已提交
5297
		if (sid == 0)
D
David Howells 已提交
5298 5299 5300 5301
			goto abort_change;

		/* Only allow single threaded processes to change context */
		error = -EPERM;
5302
		if (!current_is_single_threaded()) {
D
David Howells 已提交
5303 5304 5305
			error = security_bounded_transition(tsec->sid, sid);
			if (error)
				goto abort_change;
5306
		}
L
Linus Torvalds 已提交
5307 5308 5309

		/* Check permissions for the transition. */
		error = avc_has_perm(tsec->sid, sid, SECCLASS_PROCESS,
5310
				     PROCESS__DYNTRANSITION, NULL);
L
Linus Torvalds 已提交
5311
		if (error)
D
David Howells 已提交
5312
			goto abort_change;
L
Linus Torvalds 已提交
5313 5314 5315

		/* Check for ptracing, and update the task SID if ok.
		   Otherwise, leave SID unchanged and fail. */
D
David Howells 已提交
5316
		ptsid = 0;
L
Linus Torvalds 已提交
5317
		task_lock(p);
5318
		tracer = ptrace_parent(p);
D
David Howells 已提交
5319 5320 5321 5322 5323 5324 5325
		if (tracer)
			ptsid = task_sid(tracer);
		task_unlock(p);

		if (tracer) {
			error = avc_has_perm(ptsid, sid, SECCLASS_PROCESS,
					     PROCESS__PTRACE, NULL);
L
Linus Torvalds 已提交
5326
			if (error)
D
David Howells 已提交
5327
				goto abort_change;
L
Linus Torvalds 已提交
5328 5329
		}

D
David Howells 已提交
5330 5331 5332 5333 5334 5335 5336
		tsec->sid = sid;
	} else {
		error = -EINVAL;
		goto abort_change;
	}

	commit_creds(new);
L
Linus Torvalds 已提交
5337
	return size;
D
David Howells 已提交
5338 5339 5340 5341

abort_change:
	abort_creds(new);
	return error;
L
Linus Torvalds 已提交
5342 5343
}

5344 5345 5346 5347 5348
static int selinux_secid_to_secctx(u32 secid, char **secdata, u32 *seclen)
{
	return security_sid_to_context(secid, secdata, seclen);
}

5349
static int selinux_secctx_to_secid(const char *secdata, u32 seclen, u32 *secid)
5350 5351 5352 5353
{
	return security_context_to_sid(secdata, seclen, secid);
}

5354 5355
static void selinux_release_secctx(char *secdata, u32 seclen)
{
5356
	kfree(secdata);
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 5383 5384
/*
 *	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;
}
5385 5386
#ifdef CONFIG_KEYS

D
David Howells 已提交
5387
static int selinux_key_alloc(struct key *k, const struct cred *cred,
5388
			     unsigned long flags)
5389
{
D
David Howells 已提交
5390
	const struct task_security_struct *tsec;
5391 5392 5393 5394 5395 5396
	struct key_security_struct *ksec;

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

D
David Howells 已提交
5397 5398 5399
	tsec = cred->security;
	if (tsec->keycreate_sid)
		ksec->sid = tsec->keycreate_sid;
5400
	else
D
David Howells 已提交
5401
		ksec->sid = tsec->sid;
5402

5403
	k->security = ksec;
5404 5405 5406 5407 5408 5409 5410 5411 5412 5413 5414 5415
	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
5416 5417
				  const struct cred *cred,
				  key_perm_t perm)
5418 5419 5420
{
	struct key *key;
	struct key_security_struct *ksec;
5421
	u32 sid;
5422 5423 5424 5425 5426 5427 5428

	/* 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
5429
	sid = cred_sid(cred);
5430 5431 5432 5433 5434

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

	return avc_has_perm(sid, ksec->sid, SECCLASS_KEY, perm, NULL);
5435 5436
}

5437 5438 5439 5440 5441 5442 5443 5444 5445 5446 5447 5448 5449 5450
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;
}

5451 5452
#endif

L
Linus Torvalds 已提交
5453
static struct security_operations selinux_ops = {
5454 5455
	.name =				"selinux",

5456
	.ptrace_access_check =		selinux_ptrace_access_check,
5457
	.ptrace_traceme =		selinux_ptrace_traceme,
L
Linus Torvalds 已提交
5458
	.capget =			selinux_capget,
D
David Howells 已提交
5459
	.capset =			selinux_capset,
L
Linus Torvalds 已提交
5460 5461 5462 5463 5464 5465 5466
	.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,
5467
	.netlink_recv =			selinux_netlink_recv,
L
Linus Torvalds 已提交
5468

5469 5470 5471
	.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
5472 5473 5474 5475 5476
	.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,
5477
	.sb_remount =			selinux_sb_remount,
5478
	.sb_kern_mount =		selinux_sb_kern_mount,
5479
	.sb_show_options =		selinux_sb_show_options,
L
Linus Torvalds 已提交
5480 5481 5482
	.sb_statfs =			selinux_sb_statfs,
	.sb_mount =			selinux_mount,
	.sb_umount =			selinux_umount,
5483
	.sb_set_mnt_opts =		selinux_set_mnt_opts,
5484
	.sb_clone_mnt_opts =		selinux_sb_clone_mnt_opts,
5485 5486
	.sb_parse_opts_str = 		selinux_parse_opts_str,

L
Linus Torvalds 已提交
5487 5488 5489

	.inode_alloc_security =		selinux_inode_alloc_security,
	.inode_free_security =		selinux_inode_free_security,
5490
	.inode_init_security =		selinux_inode_init_security,
L
Linus Torvalds 已提交
5491 5492 5493 5494 5495 5496 5497 5498 5499 5500 5501 5502 5503 5504 5505 5506 5507 5508
	.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,
5509 5510 5511
	.inode_getsecurity =		selinux_inode_getsecurity,
	.inode_setsecurity =		selinux_inode_setsecurity,
	.inode_listsecurity =		selinux_inode_listsecurity,
5512
	.inode_getsecid =		selinux_inode_getsecid,
L
Linus Torvalds 已提交
5513 5514 5515 5516 5517 5518 5519 5520 5521 5522 5523 5524 5525

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

5526
	.dentry_open =			selinux_dentry_open,
5527

L
Linus Torvalds 已提交
5528
	.task_create =			selinux_task_create,
5529
	.cred_alloc_blank =		selinux_cred_alloc_blank,
5530
	.cred_free =			selinux_cred_free,
D
David Howells 已提交
5531
	.cred_prepare =			selinux_cred_prepare,
5532
	.cred_transfer =		selinux_cred_transfer,
5533 5534
	.kernel_act_as =		selinux_kernel_act_as,
	.kernel_create_files_as =	selinux_kernel_create_files_as,
5535
	.kernel_module_request =	selinux_kernel_module_request,
L
Linus Torvalds 已提交
5536 5537
	.task_setpgid =			selinux_task_setpgid,
	.task_getpgid =			selinux_task_getpgid,
5538
	.task_getsid =			selinux_task_getsid,
5539
	.task_getsecid =		selinux_task_getsecid,
L
Linus Torvalds 已提交
5540
	.task_setnice =			selinux_task_setnice,
5541
	.task_setioprio =		selinux_task_setioprio,
5542
	.task_getioprio =		selinux_task_getioprio,
L
Linus Torvalds 已提交
5543 5544 5545
	.task_setrlimit =		selinux_task_setrlimit,
	.task_setscheduler =		selinux_task_setscheduler,
	.task_getscheduler =		selinux_task_getscheduler,
5546
	.task_movememory =		selinux_task_movememory,
L
Linus Torvalds 已提交
5547 5548
	.task_kill =			selinux_task_kill,
	.task_wait =			selinux_task_wait,
5549
	.task_to_inode =		selinux_task_to_inode,
L
Linus Torvalds 已提交
5550 5551

	.ipc_permission =		selinux_ipc_permission,
5552
	.ipc_getsecid =			selinux_ipc_getsecid,
L
Linus Torvalds 已提交
5553 5554 5555 5556 5557 5558 5559 5560 5561 5562 5563 5564 5565 5566 5567 5568 5569

	.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,

5570 5571
	.sem_alloc_security =		selinux_sem_alloc_security,
	.sem_free_security =		selinux_sem_free_security,
L
Linus Torvalds 已提交
5572 5573 5574 5575
	.sem_associate =		selinux_sem_associate,
	.sem_semctl =			selinux_sem_semctl,
	.sem_semop =			selinux_sem_semop,

5576
	.d_instantiate =		selinux_d_instantiate,
L
Linus Torvalds 已提交
5577

5578 5579
	.getprocattr =			selinux_getprocattr,
	.setprocattr =			selinux_setprocattr,
L
Linus Torvalds 已提交
5580

5581
	.secid_to_secctx =		selinux_secid_to_secctx,
5582
	.secctx_to_secid =		selinux_secctx_to_secid,
5583
	.release_secctx =		selinux_release_secctx,
5584 5585 5586
	.inode_notifysecctx =		selinux_inode_notifysecctx,
	.inode_setsecctx =		selinux_inode_setsecctx,
	.inode_getsecctx =		selinux_inode_getsecctx,
5587

5588
	.unix_stream_connect =		selinux_socket_unix_stream_connect,
L
Linus Torvalds 已提交
5589 5590 5591 5592 5593 5594 5595 5596 5597 5598 5599 5600 5601 5602 5603 5604
	.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
5605 5606
	.socket_getpeersec_stream =	selinux_socket_getpeersec_stream,
	.socket_getpeersec_dgram =	selinux_socket_getpeersec_dgram,
L
Linus Torvalds 已提交
5607 5608
	.sk_alloc_security =		selinux_sk_alloc_security,
	.sk_free_security =		selinux_sk_free_security,
5609
	.sk_clone_security =		selinux_sk_clone_security,
5610
	.sk_getsecid =			selinux_sk_getsecid,
5611 5612 5613
	.sock_graft =			selinux_sock_graft,
	.inet_conn_request =		selinux_inet_conn_request,
	.inet_csk_clone =		selinux_inet_csk_clone,
5614
	.inet_conn_established =	selinux_inet_conn_established,
5615 5616 5617
	.secmark_relabel_packet =	selinux_secmark_relabel_packet,
	.secmark_refcount_inc =		selinux_secmark_refcount_inc,
	.secmark_refcount_dec =		selinux_secmark_refcount_dec,
5618
	.req_classify_flow =		selinux_req_classify_flow,
5619 5620 5621
	.tun_dev_create =		selinux_tun_dev_create,
	.tun_dev_post_create = 		selinux_tun_dev_post_create,
	.tun_dev_attach =		selinux_tun_dev_attach,
5622 5623 5624 5625 5626

#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
5627
	.xfrm_policy_delete_security =	selinux_xfrm_policy_delete,
5628 5629
	.xfrm_state_alloc_security =	selinux_xfrm_state_alloc,
	.xfrm_state_free_security =	selinux_xfrm_state_free,
C
Catherine Zhang 已提交
5630
	.xfrm_state_delete_security =	selinux_xfrm_state_delete,
5631
	.xfrm_policy_lookup =		selinux_xfrm_policy_lookup,
5632 5633
	.xfrm_state_pol_flow_match =	selinux_xfrm_state_pol_flow_match,
	.xfrm_decode_session =		selinux_xfrm_decode_session,
L
Linus Torvalds 已提交
5634
#endif
5635 5636

#ifdef CONFIG_KEYS
5637 5638 5639
	.key_alloc =			selinux_key_alloc,
	.key_free =			selinux_key_free,
	.key_permission =		selinux_key_permission,
5640
	.key_getsecurity =		selinux_key_getsecurity,
5641
#endif
5642 5643 5644 5645 5646 5647 5648

#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
5649 5650 5651 5652
};

static __init int selinux_init(void)
{
5653 5654 5655 5656 5657
	if (!security_module_enable(&selinux_ops)) {
		selinux_enabled = 0;
		return 0;
	}

L
Linus Torvalds 已提交
5658 5659 5660 5661 5662 5663 5664 5665
	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
5666
	cred_init_security();
L
Linus Torvalds 已提交
5667

5668 5669
	default_noexec = !(VM_DATA_DEFAULT_FLAGS & VM_EXEC);

5670 5671
	sel_inode_cache = kmem_cache_create("selinux_inode_security",
					    sizeof(struct inode_security_struct),
5672
					    0, SLAB_PANIC, NULL);
L
Linus Torvalds 已提交
5673 5674
	avc_init();

5675
	if (register_security(&selinux_ops))
L
Linus Torvalds 已提交
5676 5677
		panic("SELinux: Unable to register with kernel.\n");

5678
	if (selinux_enforcing)
5679
		printk(KERN_DEBUG "SELinux:  Starting in enforcing mode\n");
5680
	else
5681
		printk(KERN_DEBUG "SELinux:  Starting in permissive mode\n");
5682

L
Linus Torvalds 已提交
5683 5684 5685
	return 0;
}

5686 5687 5688 5689 5690
static void delayed_superblock_init(struct super_block *sb, void *unused)
{
	superblock_doinit(sb, NULL);
}

L
Linus Torvalds 已提交
5691 5692
void selinux_complete_init(void)
{
5693
	printk(KERN_DEBUG "SELinux:  Completing initialization.\n");
L
Linus Torvalds 已提交
5694 5695

	/* Set up any superblocks initialized prior to the policy load. */
5696
	printk(KERN_DEBUG "SELinux:  Setting up existing superblocks.\n");
5697
	iterate_supers(delayed_superblock_init, NULL);
L
Linus Torvalds 已提交
5698 5699 5700 5701 5702 5703
}

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

5704
#if defined(CONFIG_NETFILTER)
L
Linus Torvalds 已提交
5705

5706 5707 5708 5709 5710 5711 5712 5713 5714 5715 5716 5717 5718 5719
static struct nf_hook_ops selinux_ipv4_ops[] = {
	{
		.hook =		selinux_ipv4_postroute,
		.owner =	THIS_MODULE,
		.pf =		PF_INET,
		.hooknum =	NF_INET_POST_ROUTING,
		.priority =	NF_IP_PRI_SELINUX_LAST,
	},
	{
		.hook =		selinux_ipv4_forward,
		.owner =	THIS_MODULE,
		.pf =		PF_INET,
		.hooknum =	NF_INET_FORWARD,
		.priority =	NF_IP_PRI_SELINUX_FIRST,
5720 5721 5722 5723 5724 5725 5726
	},
	{
		.hook =		selinux_ipv4_output,
		.owner =	THIS_MODULE,
		.pf =		PF_INET,
		.hooknum =	NF_INET_LOCAL_OUT,
		.priority =	NF_IP_PRI_SELINUX_FIRST,
5727
	}
L
Linus Torvalds 已提交
5728 5729 5730 5731
};

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

5732 5733 5734 5735 5736 5737 5738 5739 5740 5741 5742 5743 5744 5745 5746
static struct nf_hook_ops selinux_ipv6_ops[] = {
	{
		.hook =		selinux_ipv6_postroute,
		.owner =	THIS_MODULE,
		.pf =		PF_INET6,
		.hooknum =	NF_INET_POST_ROUTING,
		.priority =	NF_IP6_PRI_SELINUX_LAST,
	},
	{
		.hook =		selinux_ipv6_forward,
		.owner =	THIS_MODULE,
		.pf =		PF_INET6,
		.hooknum =	NF_INET_FORWARD,
		.priority =	NF_IP6_PRI_SELINUX_FIRST,
	}
L
Linus Torvalds 已提交
5747 5748 5749 5750 5751 5752 5753 5754 5755 5756
};

#endif	/* IPV6 */

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

	if (!selinux_enabled)
		goto out;
5757 5758 5759

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

5760 5761 5762
	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
5763 5764

#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
5765 5766 5767
	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
5768
#endif	/* IPV6 */
5769

L
Linus Torvalds 已提交
5770 5771 5772 5773 5774 5775 5776 5777 5778
out:
	return err;
}

__initcall(selinux_nf_ip_init);

#ifdef CONFIG_SECURITY_SELINUX_DISABLE
static void selinux_nf_ip_exit(void)
{
5779
	printk(KERN_DEBUG "SELinux:  Unregistering netfilter hooks\n");
L
Linus Torvalds 已提交
5780

5781
	nf_unregister_hooks(selinux_ipv4_ops, ARRAY_SIZE(selinux_ipv4_ops));
L
Linus Torvalds 已提交
5782
#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
5783
	nf_unregister_hooks(selinux_ipv6_ops, ARRAY_SIZE(selinux_ipv6_ops));
L
Linus Torvalds 已提交
5784 5785 5786 5787
#endif	/* IPV6 */
}
#endif

5788
#else /* CONFIG_NETFILTER */
L
Linus Torvalds 已提交
5789 5790 5791 5792 5793

#ifdef CONFIG_SECURITY_SELINUX_DISABLE
#define selinux_nf_ip_exit()
#endif

5794
#endif /* CONFIG_NETFILTER */
L
Linus Torvalds 已提交
5795 5796

#ifdef CONFIG_SECURITY_SELINUX_DISABLE
5797 5798
static int selinux_disabled;

L
Linus Torvalds 已提交
5799 5800 5801 5802 5803 5804 5805 5806 5807 5808 5809 5810 5811 5812 5813
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;
5814
	selinux_enabled = 0;
L
Linus Torvalds 已提交
5815

5816
	reset_security_ops();
L
Linus Torvalds 已提交
5817

5818 5819 5820
	/* Try to destroy the avc node cache */
	avc_disable();

L
Linus Torvalds 已提交
5821 5822 5823 5824 5825 5826 5827 5828 5829
	/* Unregister netfilter hooks. */
	selinux_nf_ip_exit();

	/* Unregister selinuxfs. */
	exit_sel_fs();

	return 0;
}
#endif