hooks.c revision 89c86576ecde504da1eeb4f4882b2189ac2f9c4a
1/* 2 * NSA Security-Enhanced Linux (SELinux) security module 3 * 4 * This file contains the SELinux hook function implementations. 5 * 6 * Authors: Stephen Smalley, <sds@epoch.ncsc.mil> 7 * Chris Vance, <cvance@nai.com> 8 * Wayne Salamon, <wsalamon@nai.com> 9 * James Morris <jmorris@redhat.com> 10 * 11 * Copyright (C) 2001,2002 Networks Associates Technology, Inc. 12 * Copyright (C) 2003-2008 Red Hat, Inc., James Morris <jmorris@redhat.com> 13 * Eric Paris <eparis@redhat.com> 14 * Copyright (C) 2004-2005 Trusted Computer Solutions, Inc. 15 * <dgoeddel@trustedcs.com> 16 * Copyright (C) 2006, 2007 Hewlett-Packard Development Company, L.P. 17 * Paul Moore <paul.moore@hp.com> 18 * Copyright (C) 2007 Hitachi Software Engineering Co., Ltd. 19 * Yuichi Nakamura <ynakam@hitachisoft.jp> 20 * 21 * This program is free software; you can redistribute it and/or modify 22 * it under the terms of the GNU General Public License version 2, 23 * as published by the Free Software Foundation. 24 */ 25 26#include <linux/init.h> 27#include <linux/kernel.h> 28#include <linux/tracehook.h> 29#include <linux/errno.h> 30#include <linux/sched.h> 31#include <linux/security.h> 32#include <linux/xattr.h> 33#include <linux/capability.h> 34#include <linux/unistd.h> 35#include <linux/mm.h> 36#include <linux/mman.h> 37#include <linux/slab.h> 38#include <linux/pagemap.h> 39#include <linux/swap.h> 40#include <linux/spinlock.h> 41#include <linux/syscalls.h> 42#include <linux/file.h> 43#include <linux/fdtable.h> 44#include <linux/namei.h> 45#include <linux/mount.h> 46#include <linux/proc_fs.h> 47#include <linux/netfilter_ipv4.h> 48#include <linux/netfilter_ipv6.h> 49#include <linux/tty.h> 50#include <net/icmp.h> 51#include <net/ip.h> /* for local_port_range[] */ 52#include <net/tcp.h> /* struct or_callable used in sock_rcv_skb */ 53#include <net/net_namespace.h> 54#include <net/netlabel.h> 55#include <linux/uaccess.h> 56#include <asm/ioctls.h> 57#include <asm/atomic.h> 58#include <linux/bitops.h> 59#include <linux/interrupt.h> 60#include <linux/netdevice.h> /* for network interface checks */ 61#include <linux/netlink.h> 62#include <linux/tcp.h> 63#include <linux/udp.h> 64#include <linux/dccp.h> 65#include <linux/quota.h> 66#include <linux/un.h> /* for Unix socket types */ 67#include <net/af_unix.h> /* for Unix socket types */ 68#include <linux/parser.h> 69#include <linux/nfs_mount.h> 70#include <net/ipv6.h> 71#include <linux/hugetlb.h> 72#include <linux/personality.h> 73#include <linux/sysctl.h> 74#include <linux/audit.h> 75#include <linux/string.h> 76#include <linux/selinux.h> 77#include <linux/mutex.h> 78#include <linux/posix-timers.h> 79 80#include "avc.h" 81#include "objsec.h" 82#include "netif.h" 83#include "netnode.h" 84#include "netport.h" 85#include "xfrm.h" 86#include "netlabel.h" 87#include "audit.h" 88 89#define XATTR_SELINUX_SUFFIX "selinux" 90#define XATTR_NAME_SELINUX XATTR_SECURITY_PREFIX XATTR_SELINUX_SUFFIX 91 92#define NUM_SEL_MNT_OPTS 5 93 94extern unsigned int policydb_loaded_version; 95extern int selinux_nlmsg_lookup(u16 sclass, u16 nlmsg_type, u32 *perm); 96extern struct security_operations *security_ops; 97 98/* SECMARK reference count */ 99atomic_t selinux_secmark_refcount = ATOMIC_INIT(0); 100 101#ifdef CONFIG_SECURITY_SELINUX_DEVELOP 102int selinux_enforcing; 103 104static int __init enforcing_setup(char *str) 105{ 106 unsigned long enforcing; 107 if (!strict_strtoul(str, 0, &enforcing)) 108 selinux_enforcing = enforcing ? 1 : 0; 109 return 1; 110} 111__setup("enforcing=", enforcing_setup); 112#endif 113 114#ifdef CONFIG_SECURITY_SELINUX_BOOTPARAM 115int selinux_enabled = CONFIG_SECURITY_SELINUX_BOOTPARAM_VALUE; 116 117static int __init selinux_enabled_setup(char *str) 118{ 119 unsigned long enabled; 120 if (!strict_strtoul(str, 0, &enabled)) 121 selinux_enabled = enabled ? 1 : 0; 122 return 1; 123} 124__setup("selinux=", selinux_enabled_setup); 125#else 126int selinux_enabled = 1; 127#endif 128 129 130/* 131 * Minimal support for a secondary security module, 132 * just to allow the use of the capability module. 133 */ 134static struct security_operations *secondary_ops; 135 136/* Lists of inode and superblock security structures initialized 137 before the policy was loaded. */ 138static LIST_HEAD(superblock_security_head); 139static DEFINE_SPINLOCK(sb_security_lock); 140 141static struct kmem_cache *sel_inode_cache; 142 143/** 144 * selinux_secmark_enabled - Check to see if SECMARK is currently enabled 145 * 146 * Description: 147 * This function checks the SECMARK reference counter to see if any SECMARK 148 * targets are currently configured, if the reference counter is greater than 149 * zero SECMARK is considered to be enabled. Returns true (1) if SECMARK is 150 * enabled, false (0) if SECMARK is disabled. 151 * 152 */ 153static int selinux_secmark_enabled(void) 154{ 155 return (atomic_read(&selinux_secmark_refcount) > 0); 156} 157 158/* 159 * initialise the security for the init task 160 */ 161static void cred_init_security(void) 162{ 163 struct cred *cred = (struct cred *) current->real_cred; 164 struct task_security_struct *tsec; 165 166 tsec = kzalloc(sizeof(struct task_security_struct), GFP_KERNEL); 167 if (!tsec) 168 panic("SELinux: Failed to initialize initial task.\n"); 169 170 tsec->osid = tsec->sid = SECINITSID_KERNEL; 171 cred->security = tsec; 172} 173 174/* 175 * get the security ID of a set of credentials 176 */ 177static inline u32 cred_sid(const struct cred *cred) 178{ 179 const struct task_security_struct *tsec; 180 181 tsec = cred->security; 182 return tsec->sid; 183} 184 185/* 186 * get the objective security ID of a task 187 */ 188static inline u32 task_sid(const struct task_struct *task) 189{ 190 u32 sid; 191 192 rcu_read_lock(); 193 sid = cred_sid(__task_cred(task)); 194 rcu_read_unlock(); 195 return sid; 196} 197 198/* 199 * get the subjective security ID of the current task 200 */ 201static inline u32 current_sid(void) 202{ 203 const struct task_security_struct *tsec = current_cred()->security; 204 205 return tsec->sid; 206} 207 208/* Allocate and free functions for each kind of security blob. */ 209 210static int inode_alloc_security(struct inode *inode) 211{ 212 struct inode_security_struct *isec; 213 u32 sid = current_sid(); 214 215 isec = kmem_cache_zalloc(sel_inode_cache, GFP_NOFS); 216 if (!isec) 217 return -ENOMEM; 218 219 mutex_init(&isec->lock); 220 INIT_LIST_HEAD(&isec->list); 221 isec->inode = inode; 222 isec->sid = SECINITSID_UNLABELED; 223 isec->sclass = SECCLASS_FILE; 224 isec->task_sid = sid; 225 inode->i_security = isec; 226 227 return 0; 228} 229 230static void inode_free_security(struct inode *inode) 231{ 232 struct inode_security_struct *isec = inode->i_security; 233 struct superblock_security_struct *sbsec = inode->i_sb->s_security; 234 235 spin_lock(&sbsec->isec_lock); 236 if (!list_empty(&isec->list)) 237 list_del_init(&isec->list); 238 spin_unlock(&sbsec->isec_lock); 239 240 inode->i_security = NULL; 241 kmem_cache_free(sel_inode_cache, isec); 242} 243 244static int file_alloc_security(struct file *file) 245{ 246 struct file_security_struct *fsec; 247 u32 sid = current_sid(); 248 249 fsec = kzalloc(sizeof(struct file_security_struct), GFP_KERNEL); 250 if (!fsec) 251 return -ENOMEM; 252 253 fsec->sid = sid; 254 fsec->fown_sid = sid; 255 file->f_security = fsec; 256 257 return 0; 258} 259 260static void file_free_security(struct file *file) 261{ 262 struct file_security_struct *fsec = file->f_security; 263 file->f_security = NULL; 264 kfree(fsec); 265} 266 267static int superblock_alloc_security(struct super_block *sb) 268{ 269 struct superblock_security_struct *sbsec; 270 271 sbsec = kzalloc(sizeof(struct superblock_security_struct), GFP_KERNEL); 272 if (!sbsec) 273 return -ENOMEM; 274 275 mutex_init(&sbsec->lock); 276 INIT_LIST_HEAD(&sbsec->list); 277 INIT_LIST_HEAD(&sbsec->isec_head); 278 spin_lock_init(&sbsec->isec_lock); 279 sbsec->sb = sb; 280 sbsec->sid = SECINITSID_UNLABELED; 281 sbsec->def_sid = SECINITSID_FILE; 282 sbsec->mntpoint_sid = SECINITSID_UNLABELED; 283 sb->s_security = sbsec; 284 285 return 0; 286} 287 288static void superblock_free_security(struct super_block *sb) 289{ 290 struct superblock_security_struct *sbsec = sb->s_security; 291 292 spin_lock(&sb_security_lock); 293 if (!list_empty(&sbsec->list)) 294 list_del_init(&sbsec->list); 295 spin_unlock(&sb_security_lock); 296 297 sb->s_security = NULL; 298 kfree(sbsec); 299} 300 301static int sk_alloc_security(struct sock *sk, int family, gfp_t priority) 302{ 303 struct sk_security_struct *ssec; 304 305 ssec = kzalloc(sizeof(*ssec), priority); 306 if (!ssec) 307 return -ENOMEM; 308 309 ssec->peer_sid = SECINITSID_UNLABELED; 310 ssec->sid = SECINITSID_UNLABELED; 311 sk->sk_security = ssec; 312 313 selinux_netlbl_sk_security_reset(ssec); 314 315 return 0; 316} 317 318static void sk_free_security(struct sock *sk) 319{ 320 struct sk_security_struct *ssec = sk->sk_security; 321 322 sk->sk_security = NULL; 323 selinux_netlbl_sk_security_free(ssec); 324 kfree(ssec); 325} 326 327/* The security server must be initialized before 328 any labeling or access decisions can be provided. */ 329extern int ss_initialized; 330 331/* The file system's label must be initialized prior to use. */ 332 333static char *labeling_behaviors[6] = { 334 "uses xattr", 335 "uses transition SIDs", 336 "uses task SIDs", 337 "uses genfs_contexts", 338 "not configured for labeling", 339 "uses mountpoint labeling", 340}; 341 342static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dentry); 343 344static inline int inode_doinit(struct inode *inode) 345{ 346 return inode_doinit_with_dentry(inode, NULL); 347} 348 349enum { 350 Opt_error = -1, 351 Opt_context = 1, 352 Opt_fscontext = 2, 353 Opt_defcontext = 3, 354 Opt_rootcontext = 4, 355 Opt_labelsupport = 5, 356}; 357 358static const match_table_t tokens = { 359 {Opt_context, CONTEXT_STR "%s"}, 360 {Opt_fscontext, FSCONTEXT_STR "%s"}, 361 {Opt_defcontext, DEFCONTEXT_STR "%s"}, 362 {Opt_rootcontext, ROOTCONTEXT_STR "%s"}, 363 {Opt_labelsupport, LABELSUPP_STR}, 364 {Opt_error, NULL}, 365}; 366 367#define SEL_MOUNT_FAIL_MSG "SELinux: duplicate or incompatible mount options\n" 368 369static int may_context_mount_sb_relabel(u32 sid, 370 struct superblock_security_struct *sbsec, 371 const struct cred *cred) 372{ 373 const struct task_security_struct *tsec = cred->security; 374 int rc; 375 376 rc = avc_has_perm(tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM, 377 FILESYSTEM__RELABELFROM, NULL); 378 if (rc) 379 return rc; 380 381 rc = avc_has_perm(tsec->sid, sid, SECCLASS_FILESYSTEM, 382 FILESYSTEM__RELABELTO, NULL); 383 return rc; 384} 385 386static int may_context_mount_inode_relabel(u32 sid, 387 struct superblock_security_struct *sbsec, 388 const struct cred *cred) 389{ 390 const struct task_security_struct *tsec = cred->security; 391 int rc; 392 rc = avc_has_perm(tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM, 393 FILESYSTEM__RELABELFROM, NULL); 394 if (rc) 395 return rc; 396 397 rc = avc_has_perm(sid, sbsec->sid, SECCLASS_FILESYSTEM, 398 FILESYSTEM__ASSOCIATE, NULL); 399 return rc; 400} 401 402static int sb_finish_set_opts(struct super_block *sb) 403{ 404 struct superblock_security_struct *sbsec = sb->s_security; 405 struct dentry *root = sb->s_root; 406 struct inode *root_inode = root->d_inode; 407 int rc = 0; 408 409 if (sbsec->behavior == SECURITY_FS_USE_XATTR) { 410 /* Make sure that the xattr handler exists and that no 411 error other than -ENODATA is returned by getxattr on 412 the root directory. -ENODATA is ok, as this may be 413 the first boot of the SELinux kernel before we have 414 assigned xattr values to the filesystem. */ 415 if (!root_inode->i_op->getxattr) { 416 printk(KERN_WARNING "SELinux: (dev %s, type %s) has no " 417 "xattr support\n", sb->s_id, sb->s_type->name); 418 rc = -EOPNOTSUPP; 419 goto out; 420 } 421 rc = root_inode->i_op->getxattr(root, XATTR_NAME_SELINUX, NULL, 0); 422 if (rc < 0 && rc != -ENODATA) { 423 if (rc == -EOPNOTSUPP) 424 printk(KERN_WARNING "SELinux: (dev %s, type " 425 "%s) has no security xattr handler\n", 426 sb->s_id, sb->s_type->name); 427 else 428 printk(KERN_WARNING "SELinux: (dev %s, type " 429 "%s) getxattr errno %d\n", sb->s_id, 430 sb->s_type->name, -rc); 431 goto out; 432 } 433 } 434 435 sbsec->flags |= (SE_SBINITIALIZED | SE_SBLABELSUPP); 436 437 if (sbsec->behavior > ARRAY_SIZE(labeling_behaviors)) 438 printk(KERN_ERR "SELinux: initialized (dev %s, type %s), unknown behavior\n", 439 sb->s_id, sb->s_type->name); 440 else 441 printk(KERN_DEBUG "SELinux: initialized (dev %s, type %s), %s\n", 442 sb->s_id, sb->s_type->name, 443 labeling_behaviors[sbsec->behavior-1]); 444 445 if (sbsec->behavior == SECURITY_FS_USE_GENFS || 446 sbsec->behavior == SECURITY_FS_USE_MNTPOINT || 447 sbsec->behavior == SECURITY_FS_USE_NONE || 448 sbsec->behavior > ARRAY_SIZE(labeling_behaviors)) 449 sbsec->flags &= ~SE_SBLABELSUPP; 450 451 /* Initialize the root inode. */ 452 rc = inode_doinit_with_dentry(root_inode, root); 453 454 /* Initialize any other inodes associated with the superblock, e.g. 455 inodes created prior to initial policy load or inodes created 456 during get_sb by a pseudo filesystem that directly 457 populates itself. */ 458 spin_lock(&sbsec->isec_lock); 459next_inode: 460 if (!list_empty(&sbsec->isec_head)) { 461 struct inode_security_struct *isec = 462 list_entry(sbsec->isec_head.next, 463 struct inode_security_struct, list); 464 struct inode *inode = isec->inode; 465 spin_unlock(&sbsec->isec_lock); 466 inode = igrab(inode); 467 if (inode) { 468 if (!IS_PRIVATE(inode)) 469 inode_doinit(inode); 470 iput(inode); 471 } 472 spin_lock(&sbsec->isec_lock); 473 list_del_init(&isec->list); 474 goto next_inode; 475 } 476 spin_unlock(&sbsec->isec_lock); 477out: 478 return rc; 479} 480 481/* 482 * This function should allow an FS to ask what it's mount security 483 * options were so it can use those later for submounts, displaying 484 * mount options, or whatever. 485 */ 486static int selinux_get_mnt_opts(const struct super_block *sb, 487 struct security_mnt_opts *opts) 488{ 489 int rc = 0, i; 490 struct superblock_security_struct *sbsec = sb->s_security; 491 char *context = NULL; 492 u32 len; 493 char tmp; 494 495 security_init_mnt_opts(opts); 496 497 if (!(sbsec->flags & SE_SBINITIALIZED)) 498 return -EINVAL; 499 500 if (!ss_initialized) 501 return -EINVAL; 502 503 tmp = sbsec->flags & SE_MNTMASK; 504 /* count the number of mount options for this sb */ 505 for (i = 0; i < 8; i++) { 506 if (tmp & 0x01) 507 opts->num_mnt_opts++; 508 tmp >>= 1; 509 } 510 /* Check if the Label support flag is set */ 511 if (sbsec->flags & SE_SBLABELSUPP) 512 opts->num_mnt_opts++; 513 514 opts->mnt_opts = kcalloc(opts->num_mnt_opts, sizeof(char *), GFP_ATOMIC); 515 if (!opts->mnt_opts) { 516 rc = -ENOMEM; 517 goto out_free; 518 } 519 520 opts->mnt_opts_flags = kcalloc(opts->num_mnt_opts, sizeof(int), GFP_ATOMIC); 521 if (!opts->mnt_opts_flags) { 522 rc = -ENOMEM; 523 goto out_free; 524 } 525 526 i = 0; 527 if (sbsec->flags & FSCONTEXT_MNT) { 528 rc = security_sid_to_context(sbsec->sid, &context, &len); 529 if (rc) 530 goto out_free; 531 opts->mnt_opts[i] = context; 532 opts->mnt_opts_flags[i++] = FSCONTEXT_MNT; 533 } 534 if (sbsec->flags & CONTEXT_MNT) { 535 rc = security_sid_to_context(sbsec->mntpoint_sid, &context, &len); 536 if (rc) 537 goto out_free; 538 opts->mnt_opts[i] = context; 539 opts->mnt_opts_flags[i++] = CONTEXT_MNT; 540 } 541 if (sbsec->flags & DEFCONTEXT_MNT) { 542 rc = security_sid_to_context(sbsec->def_sid, &context, &len); 543 if (rc) 544 goto out_free; 545 opts->mnt_opts[i] = context; 546 opts->mnt_opts_flags[i++] = DEFCONTEXT_MNT; 547 } 548 if (sbsec->flags & ROOTCONTEXT_MNT) { 549 struct inode *root = sbsec->sb->s_root->d_inode; 550 struct inode_security_struct *isec = root->i_security; 551 552 rc = security_sid_to_context(isec->sid, &context, &len); 553 if (rc) 554 goto out_free; 555 opts->mnt_opts[i] = context; 556 opts->mnt_opts_flags[i++] = ROOTCONTEXT_MNT; 557 } 558 if (sbsec->flags & SE_SBLABELSUPP) { 559 opts->mnt_opts[i] = NULL; 560 opts->mnt_opts_flags[i++] = SE_SBLABELSUPP; 561 } 562 563 BUG_ON(i != opts->num_mnt_opts); 564 565 return 0; 566 567out_free: 568 security_free_mnt_opts(opts); 569 return rc; 570} 571 572static int bad_option(struct superblock_security_struct *sbsec, char flag, 573 u32 old_sid, u32 new_sid) 574{ 575 char mnt_flags = sbsec->flags & SE_MNTMASK; 576 577 /* check if the old mount command had the same options */ 578 if (sbsec->flags & SE_SBINITIALIZED) 579 if (!(sbsec->flags & flag) || 580 (old_sid != new_sid)) 581 return 1; 582 583 /* check if we were passed the same options twice, 584 * aka someone passed context=a,context=b 585 */ 586 if (!(sbsec->flags & SE_SBINITIALIZED)) 587 if (mnt_flags & flag) 588 return 1; 589 return 0; 590} 591 592/* 593 * Allow filesystems with binary mount data to explicitly set mount point 594 * labeling information. 595 */ 596static int selinux_set_mnt_opts(struct super_block *sb, 597 struct security_mnt_opts *opts) 598{ 599 const struct cred *cred = current_cred(); 600 int rc = 0, i; 601 struct superblock_security_struct *sbsec = sb->s_security; 602 const char *name = sb->s_type->name; 603 struct inode *inode = sbsec->sb->s_root->d_inode; 604 struct inode_security_struct *root_isec = inode->i_security; 605 u32 fscontext_sid = 0, context_sid = 0, rootcontext_sid = 0; 606 u32 defcontext_sid = 0; 607 char **mount_options = opts->mnt_opts; 608 int *flags = opts->mnt_opts_flags; 609 int num_opts = opts->num_mnt_opts; 610 611 mutex_lock(&sbsec->lock); 612 613 if (!ss_initialized) { 614 if (!num_opts) { 615 /* Defer initialization until selinux_complete_init, 616 after the initial policy is loaded and the security 617 server is ready to handle calls. */ 618 spin_lock(&sb_security_lock); 619 if (list_empty(&sbsec->list)) 620 list_add(&sbsec->list, &superblock_security_head); 621 spin_unlock(&sb_security_lock); 622 goto out; 623 } 624 rc = -EINVAL; 625 printk(KERN_WARNING "SELinux: Unable to set superblock options " 626 "before the security server is initialized\n"); 627 goto out; 628 } 629 630 /* 631 * Binary mount data FS will come through this function twice. Once 632 * from an explicit call and once from the generic calls from the vfs. 633 * Since the generic VFS calls will not contain any security mount data 634 * we need to skip the double mount verification. 635 * 636 * This does open a hole in which we will not notice if the first 637 * mount using this sb set explict options and a second mount using 638 * this sb does not set any security options. (The first options 639 * will be used for both mounts) 640 */ 641 if ((sbsec->flags & SE_SBINITIALIZED) && (sb->s_type->fs_flags & FS_BINARY_MOUNTDATA) 642 && (num_opts == 0)) 643 goto out; 644 645 /* 646 * parse the mount options, check if they are valid sids. 647 * also check if someone is trying to mount the same sb more 648 * than once with different security options. 649 */ 650 for (i = 0; i < num_opts; i++) { 651 u32 sid; 652 653 if (flags[i] == SE_SBLABELSUPP) 654 continue; 655 rc = security_context_to_sid(mount_options[i], 656 strlen(mount_options[i]), &sid); 657 if (rc) { 658 printk(KERN_WARNING "SELinux: security_context_to_sid" 659 "(%s) failed for (dev %s, type %s) errno=%d\n", 660 mount_options[i], sb->s_id, name, rc); 661 goto out; 662 } 663 switch (flags[i]) { 664 case FSCONTEXT_MNT: 665 fscontext_sid = sid; 666 667 if (bad_option(sbsec, FSCONTEXT_MNT, sbsec->sid, 668 fscontext_sid)) 669 goto out_double_mount; 670 671 sbsec->flags |= FSCONTEXT_MNT; 672 break; 673 case CONTEXT_MNT: 674 context_sid = sid; 675 676 if (bad_option(sbsec, CONTEXT_MNT, sbsec->mntpoint_sid, 677 context_sid)) 678 goto out_double_mount; 679 680 sbsec->flags |= CONTEXT_MNT; 681 break; 682 case ROOTCONTEXT_MNT: 683 rootcontext_sid = sid; 684 685 if (bad_option(sbsec, ROOTCONTEXT_MNT, root_isec->sid, 686 rootcontext_sid)) 687 goto out_double_mount; 688 689 sbsec->flags |= ROOTCONTEXT_MNT; 690 691 break; 692 case DEFCONTEXT_MNT: 693 defcontext_sid = sid; 694 695 if (bad_option(sbsec, DEFCONTEXT_MNT, sbsec->def_sid, 696 defcontext_sid)) 697 goto out_double_mount; 698 699 sbsec->flags |= DEFCONTEXT_MNT; 700 701 break; 702 default: 703 rc = -EINVAL; 704 goto out; 705 } 706 } 707 708 if (sbsec->flags & SE_SBINITIALIZED) { 709 /* previously mounted with options, but not on this attempt? */ 710 if ((sbsec->flags & SE_MNTMASK) && !num_opts) 711 goto out_double_mount; 712 rc = 0; 713 goto out; 714 } 715 716 if (strcmp(sb->s_type->name, "proc") == 0) 717 sbsec->flags |= SE_SBPROC; 718 719 /* Determine the labeling behavior to use for this filesystem type. */ 720 rc = security_fs_use((sbsec->flags & SE_SBPROC) ? "proc" : sb->s_type->name, &sbsec->behavior, &sbsec->sid); 721 if (rc) { 722 printk(KERN_WARNING "%s: security_fs_use(%s) returned %d\n", 723 __func__, sb->s_type->name, rc); 724 goto out; 725 } 726 727 /* sets the context of the superblock for the fs being mounted. */ 728 if (fscontext_sid) { 729 rc = may_context_mount_sb_relabel(fscontext_sid, sbsec, cred); 730 if (rc) 731 goto out; 732 733 sbsec->sid = fscontext_sid; 734 } 735 736 /* 737 * Switch to using mount point labeling behavior. 738 * sets the label used on all file below the mountpoint, and will set 739 * the superblock context if not already set. 740 */ 741 if (context_sid) { 742 if (!fscontext_sid) { 743 rc = may_context_mount_sb_relabel(context_sid, sbsec, 744 cred); 745 if (rc) 746 goto out; 747 sbsec->sid = context_sid; 748 } else { 749 rc = may_context_mount_inode_relabel(context_sid, sbsec, 750 cred); 751 if (rc) 752 goto out; 753 } 754 if (!rootcontext_sid) 755 rootcontext_sid = context_sid; 756 757 sbsec->mntpoint_sid = context_sid; 758 sbsec->behavior = SECURITY_FS_USE_MNTPOINT; 759 } 760 761 if (rootcontext_sid) { 762 rc = may_context_mount_inode_relabel(rootcontext_sid, sbsec, 763 cred); 764 if (rc) 765 goto out; 766 767 root_isec->sid = rootcontext_sid; 768 root_isec->initialized = 1; 769 } 770 771 if (defcontext_sid) { 772 if (sbsec->behavior != SECURITY_FS_USE_XATTR) { 773 rc = -EINVAL; 774 printk(KERN_WARNING "SELinux: defcontext option is " 775 "invalid for this filesystem type\n"); 776 goto out; 777 } 778 779 if (defcontext_sid != sbsec->def_sid) { 780 rc = may_context_mount_inode_relabel(defcontext_sid, 781 sbsec, cred); 782 if (rc) 783 goto out; 784 } 785 786 sbsec->def_sid = defcontext_sid; 787 } 788 789 rc = sb_finish_set_opts(sb); 790out: 791 mutex_unlock(&sbsec->lock); 792 return rc; 793out_double_mount: 794 rc = -EINVAL; 795 printk(KERN_WARNING "SELinux: mount invalid. Same superblock, different " 796 "security settings for (dev %s, type %s)\n", sb->s_id, name); 797 goto out; 798} 799 800static void selinux_sb_clone_mnt_opts(const struct super_block *oldsb, 801 struct super_block *newsb) 802{ 803 const struct superblock_security_struct *oldsbsec = oldsb->s_security; 804 struct superblock_security_struct *newsbsec = newsb->s_security; 805 806 int set_fscontext = (oldsbsec->flags & FSCONTEXT_MNT); 807 int set_context = (oldsbsec->flags & CONTEXT_MNT); 808 int set_rootcontext = (oldsbsec->flags & ROOTCONTEXT_MNT); 809 810 /* 811 * if the parent was able to be mounted it clearly had no special lsm 812 * mount options. thus we can safely put this sb on the list and deal 813 * with it later 814 */ 815 if (!ss_initialized) { 816 spin_lock(&sb_security_lock); 817 if (list_empty(&newsbsec->list)) 818 list_add(&newsbsec->list, &superblock_security_head); 819 spin_unlock(&sb_security_lock); 820 return; 821 } 822 823 /* how can we clone if the old one wasn't set up?? */ 824 BUG_ON(!(oldsbsec->flags & SE_SBINITIALIZED)); 825 826 /* if fs is reusing a sb, just let its options stand... */ 827 if (newsbsec->flags & SE_SBINITIALIZED) 828 return; 829 830 mutex_lock(&newsbsec->lock); 831 832 newsbsec->flags = oldsbsec->flags; 833 834 newsbsec->sid = oldsbsec->sid; 835 newsbsec->def_sid = oldsbsec->def_sid; 836 newsbsec->behavior = oldsbsec->behavior; 837 838 if (set_context) { 839 u32 sid = oldsbsec->mntpoint_sid; 840 841 if (!set_fscontext) 842 newsbsec->sid = sid; 843 if (!set_rootcontext) { 844 struct inode *newinode = newsb->s_root->d_inode; 845 struct inode_security_struct *newisec = newinode->i_security; 846 newisec->sid = sid; 847 } 848 newsbsec->mntpoint_sid = sid; 849 } 850 if (set_rootcontext) { 851 const struct inode *oldinode = oldsb->s_root->d_inode; 852 const struct inode_security_struct *oldisec = oldinode->i_security; 853 struct inode *newinode = newsb->s_root->d_inode; 854 struct inode_security_struct *newisec = newinode->i_security; 855 856 newisec->sid = oldisec->sid; 857 } 858 859 sb_finish_set_opts(newsb); 860 mutex_unlock(&newsbsec->lock); 861} 862 863static int selinux_parse_opts_str(char *options, 864 struct security_mnt_opts *opts) 865{ 866 char *p; 867 char *context = NULL, *defcontext = NULL; 868 char *fscontext = NULL, *rootcontext = NULL; 869 int rc, num_mnt_opts = 0; 870 871 opts->num_mnt_opts = 0; 872 873 /* Standard string-based options. */ 874 while ((p = strsep(&options, "|")) != NULL) { 875 int token; 876 substring_t args[MAX_OPT_ARGS]; 877 878 if (!*p) 879 continue; 880 881 token = match_token(p, tokens, args); 882 883 switch (token) { 884 case Opt_context: 885 if (context || defcontext) { 886 rc = -EINVAL; 887 printk(KERN_WARNING SEL_MOUNT_FAIL_MSG); 888 goto out_err; 889 } 890 context = match_strdup(&args[0]); 891 if (!context) { 892 rc = -ENOMEM; 893 goto out_err; 894 } 895 break; 896 897 case Opt_fscontext: 898 if (fscontext) { 899 rc = -EINVAL; 900 printk(KERN_WARNING SEL_MOUNT_FAIL_MSG); 901 goto out_err; 902 } 903 fscontext = match_strdup(&args[0]); 904 if (!fscontext) { 905 rc = -ENOMEM; 906 goto out_err; 907 } 908 break; 909 910 case Opt_rootcontext: 911 if (rootcontext) { 912 rc = -EINVAL; 913 printk(KERN_WARNING SEL_MOUNT_FAIL_MSG); 914 goto out_err; 915 } 916 rootcontext = match_strdup(&args[0]); 917 if (!rootcontext) { 918 rc = -ENOMEM; 919 goto out_err; 920 } 921 break; 922 923 case Opt_defcontext: 924 if (context || defcontext) { 925 rc = -EINVAL; 926 printk(KERN_WARNING SEL_MOUNT_FAIL_MSG); 927 goto out_err; 928 } 929 defcontext = match_strdup(&args[0]); 930 if (!defcontext) { 931 rc = -ENOMEM; 932 goto out_err; 933 } 934 break; 935 case Opt_labelsupport: 936 break; 937 default: 938 rc = -EINVAL; 939 printk(KERN_WARNING "SELinux: unknown mount option\n"); 940 goto out_err; 941 942 } 943 } 944 945 rc = -ENOMEM; 946 opts->mnt_opts = kcalloc(NUM_SEL_MNT_OPTS, sizeof(char *), GFP_ATOMIC); 947 if (!opts->mnt_opts) 948 goto out_err; 949 950 opts->mnt_opts_flags = kcalloc(NUM_SEL_MNT_OPTS, sizeof(int), GFP_ATOMIC); 951 if (!opts->mnt_opts_flags) { 952 kfree(opts->mnt_opts); 953 goto out_err; 954 } 955 956 if (fscontext) { 957 opts->mnt_opts[num_mnt_opts] = fscontext; 958 opts->mnt_opts_flags[num_mnt_opts++] = FSCONTEXT_MNT; 959 } 960 if (context) { 961 opts->mnt_opts[num_mnt_opts] = context; 962 opts->mnt_opts_flags[num_mnt_opts++] = CONTEXT_MNT; 963 } 964 if (rootcontext) { 965 opts->mnt_opts[num_mnt_opts] = rootcontext; 966 opts->mnt_opts_flags[num_mnt_opts++] = ROOTCONTEXT_MNT; 967 } 968 if (defcontext) { 969 opts->mnt_opts[num_mnt_opts] = defcontext; 970 opts->mnt_opts_flags[num_mnt_opts++] = DEFCONTEXT_MNT; 971 } 972 973 opts->num_mnt_opts = num_mnt_opts; 974 return 0; 975 976out_err: 977 kfree(context); 978 kfree(defcontext); 979 kfree(fscontext); 980 kfree(rootcontext); 981 return rc; 982} 983/* 984 * string mount options parsing and call set the sbsec 985 */ 986static int superblock_doinit(struct super_block *sb, void *data) 987{ 988 int rc = 0; 989 char *options = data; 990 struct security_mnt_opts opts; 991 992 security_init_mnt_opts(&opts); 993 994 if (!data) 995 goto out; 996 997 BUG_ON(sb->s_type->fs_flags & FS_BINARY_MOUNTDATA); 998 999 rc = selinux_parse_opts_str(options, &opts); 1000 if (rc) 1001 goto out_err; 1002 1003out: 1004 rc = selinux_set_mnt_opts(sb, &opts); 1005 1006out_err: 1007 security_free_mnt_opts(&opts); 1008 return rc; 1009} 1010 1011static void selinux_write_opts(struct seq_file *m, 1012 struct security_mnt_opts *opts) 1013{ 1014 int i; 1015 char *prefix; 1016 1017 for (i = 0; i < opts->num_mnt_opts; i++) { 1018 char *has_comma; 1019 1020 if (opts->mnt_opts[i]) 1021 has_comma = strchr(opts->mnt_opts[i], ','); 1022 else 1023 has_comma = NULL; 1024 1025 switch (opts->mnt_opts_flags[i]) { 1026 case CONTEXT_MNT: 1027 prefix = CONTEXT_STR; 1028 break; 1029 case FSCONTEXT_MNT: 1030 prefix = FSCONTEXT_STR; 1031 break; 1032 case ROOTCONTEXT_MNT: 1033 prefix = ROOTCONTEXT_STR; 1034 break; 1035 case DEFCONTEXT_MNT: 1036 prefix = DEFCONTEXT_STR; 1037 break; 1038 case SE_SBLABELSUPP: 1039 seq_putc(m, ','); 1040 seq_puts(m, LABELSUPP_STR); 1041 continue; 1042 default: 1043 BUG(); 1044 }; 1045 /* we need a comma before each option */ 1046 seq_putc(m, ','); 1047 seq_puts(m, prefix); 1048 if (has_comma) 1049 seq_putc(m, '\"'); 1050 seq_puts(m, opts->mnt_opts[i]); 1051 if (has_comma) 1052 seq_putc(m, '\"'); 1053 } 1054} 1055 1056static int selinux_sb_show_options(struct seq_file *m, struct super_block *sb) 1057{ 1058 struct security_mnt_opts opts; 1059 int rc; 1060 1061 rc = selinux_get_mnt_opts(sb, &opts); 1062 if (rc) { 1063 /* before policy load we may get EINVAL, don't show anything */ 1064 if (rc == -EINVAL) 1065 rc = 0; 1066 return rc; 1067 } 1068 1069 selinux_write_opts(m, &opts); 1070 1071 security_free_mnt_opts(&opts); 1072 1073 return rc; 1074} 1075 1076static inline u16 inode_mode_to_security_class(umode_t mode) 1077{ 1078 switch (mode & S_IFMT) { 1079 case S_IFSOCK: 1080 return SECCLASS_SOCK_FILE; 1081 case S_IFLNK: 1082 return SECCLASS_LNK_FILE; 1083 case S_IFREG: 1084 return SECCLASS_FILE; 1085 case S_IFBLK: 1086 return SECCLASS_BLK_FILE; 1087 case S_IFDIR: 1088 return SECCLASS_DIR; 1089 case S_IFCHR: 1090 return SECCLASS_CHR_FILE; 1091 case S_IFIFO: 1092 return SECCLASS_FIFO_FILE; 1093 1094 } 1095 1096 return SECCLASS_FILE; 1097} 1098 1099static inline int default_protocol_stream(int protocol) 1100{ 1101 return (protocol == IPPROTO_IP || protocol == IPPROTO_TCP); 1102} 1103 1104static inline int default_protocol_dgram(int protocol) 1105{ 1106 return (protocol == IPPROTO_IP || protocol == IPPROTO_UDP); 1107} 1108 1109static inline u16 socket_type_to_security_class(int family, int type, int protocol) 1110{ 1111 switch (family) { 1112 case PF_UNIX: 1113 switch (type) { 1114 case SOCK_STREAM: 1115 case SOCK_SEQPACKET: 1116 return SECCLASS_UNIX_STREAM_SOCKET; 1117 case SOCK_DGRAM: 1118 return SECCLASS_UNIX_DGRAM_SOCKET; 1119 } 1120 break; 1121 case PF_INET: 1122 case PF_INET6: 1123 switch (type) { 1124 case SOCK_STREAM: 1125 if (default_protocol_stream(protocol)) 1126 return SECCLASS_TCP_SOCKET; 1127 else 1128 return SECCLASS_RAWIP_SOCKET; 1129 case SOCK_DGRAM: 1130 if (default_protocol_dgram(protocol)) 1131 return SECCLASS_UDP_SOCKET; 1132 else 1133 return SECCLASS_RAWIP_SOCKET; 1134 case SOCK_DCCP: 1135 return SECCLASS_DCCP_SOCKET; 1136 default: 1137 return SECCLASS_RAWIP_SOCKET; 1138 } 1139 break; 1140 case PF_NETLINK: 1141 switch (protocol) { 1142 case NETLINK_ROUTE: 1143 return SECCLASS_NETLINK_ROUTE_SOCKET; 1144 case NETLINK_FIREWALL: 1145 return SECCLASS_NETLINK_FIREWALL_SOCKET; 1146 case NETLINK_INET_DIAG: 1147 return SECCLASS_NETLINK_TCPDIAG_SOCKET; 1148 case NETLINK_NFLOG: 1149 return SECCLASS_NETLINK_NFLOG_SOCKET; 1150 case NETLINK_XFRM: 1151 return SECCLASS_NETLINK_XFRM_SOCKET; 1152 case NETLINK_SELINUX: 1153 return SECCLASS_NETLINK_SELINUX_SOCKET; 1154 case NETLINK_AUDIT: 1155 return SECCLASS_NETLINK_AUDIT_SOCKET; 1156 case NETLINK_IP6_FW: 1157 return SECCLASS_NETLINK_IP6FW_SOCKET; 1158 case NETLINK_DNRTMSG: 1159 return SECCLASS_NETLINK_DNRT_SOCKET; 1160 case NETLINK_KOBJECT_UEVENT: 1161 return SECCLASS_NETLINK_KOBJECT_UEVENT_SOCKET; 1162 default: 1163 return SECCLASS_NETLINK_SOCKET; 1164 } 1165 case PF_PACKET: 1166 return SECCLASS_PACKET_SOCKET; 1167 case PF_KEY: 1168 return SECCLASS_KEY_SOCKET; 1169 case PF_APPLETALK: 1170 return SECCLASS_APPLETALK_SOCKET; 1171 } 1172 1173 return SECCLASS_SOCKET; 1174} 1175 1176#ifdef CONFIG_PROC_FS 1177static int selinux_proc_get_sid(struct proc_dir_entry *de, 1178 u16 tclass, 1179 u32 *sid) 1180{ 1181 int buflen, rc; 1182 char *buffer, *path, *end; 1183 1184 buffer = (char *)__get_free_page(GFP_KERNEL); 1185 if (!buffer) 1186 return -ENOMEM; 1187 1188 buflen = PAGE_SIZE; 1189 end = buffer+buflen; 1190 *--end = '\0'; 1191 buflen--; 1192 path = end-1; 1193 *path = '/'; 1194 while (de && de != de->parent) { 1195 buflen -= de->namelen + 1; 1196 if (buflen < 0) 1197 break; 1198 end -= de->namelen; 1199 memcpy(end, de->name, de->namelen); 1200 *--end = '/'; 1201 path = end; 1202 de = de->parent; 1203 } 1204 rc = security_genfs_sid("proc", path, tclass, sid); 1205 free_page((unsigned long)buffer); 1206 return rc; 1207} 1208#else 1209static int selinux_proc_get_sid(struct proc_dir_entry *de, 1210 u16 tclass, 1211 u32 *sid) 1212{ 1213 return -EINVAL; 1214} 1215#endif 1216 1217/* The inode's security attributes must be initialized before first use. */ 1218static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dentry) 1219{ 1220 struct superblock_security_struct *sbsec = NULL; 1221 struct inode_security_struct *isec = inode->i_security; 1222 u32 sid; 1223 struct dentry *dentry; 1224#define INITCONTEXTLEN 255 1225 char *context = NULL; 1226 unsigned len = 0; 1227 int rc = 0; 1228 1229 if (isec->initialized) 1230 goto out; 1231 1232 mutex_lock(&isec->lock); 1233 if (isec->initialized) 1234 goto out_unlock; 1235 1236 sbsec = inode->i_sb->s_security; 1237 if (!(sbsec->flags & SE_SBINITIALIZED)) { 1238 /* Defer initialization until selinux_complete_init, 1239 after the initial policy is loaded and the security 1240 server is ready to handle calls. */ 1241 spin_lock(&sbsec->isec_lock); 1242 if (list_empty(&isec->list)) 1243 list_add(&isec->list, &sbsec->isec_head); 1244 spin_unlock(&sbsec->isec_lock); 1245 goto out_unlock; 1246 } 1247 1248 switch (sbsec->behavior) { 1249 case SECURITY_FS_USE_XATTR: 1250 if (!inode->i_op->getxattr) { 1251 isec->sid = sbsec->def_sid; 1252 break; 1253 } 1254 1255 /* Need a dentry, since the xattr API requires one. 1256 Life would be simpler if we could just pass the inode. */ 1257 if (opt_dentry) { 1258 /* Called from d_instantiate or d_splice_alias. */ 1259 dentry = dget(opt_dentry); 1260 } else { 1261 /* Called from selinux_complete_init, try to find a dentry. */ 1262 dentry = d_find_alias(inode); 1263 } 1264 if (!dentry) { 1265 /* 1266 * this is can be hit on boot when a file is accessed 1267 * before the policy is loaded. When we load policy we 1268 * may find inodes that have no dentry on the 1269 * sbsec->isec_head list. No reason to complain as these 1270 * will get fixed up the next time we go through 1271 * inode_doinit with a dentry, before these inodes could 1272 * be used again by userspace. 1273 */ 1274 goto out_unlock; 1275 } 1276 1277 len = INITCONTEXTLEN; 1278 context = kmalloc(len+1, GFP_NOFS); 1279 if (!context) { 1280 rc = -ENOMEM; 1281 dput(dentry); 1282 goto out_unlock; 1283 } 1284 context[len] = '\0'; 1285 rc = inode->i_op->getxattr(dentry, XATTR_NAME_SELINUX, 1286 context, len); 1287 if (rc == -ERANGE) { 1288 /* Need a larger buffer. Query for the right size. */ 1289 rc = inode->i_op->getxattr(dentry, XATTR_NAME_SELINUX, 1290 NULL, 0); 1291 if (rc < 0) { 1292 dput(dentry); 1293 goto out_unlock; 1294 } 1295 kfree(context); 1296 len = rc; 1297 context = kmalloc(len+1, GFP_NOFS); 1298 if (!context) { 1299 rc = -ENOMEM; 1300 dput(dentry); 1301 goto out_unlock; 1302 } 1303 context[len] = '\0'; 1304 rc = inode->i_op->getxattr(dentry, 1305 XATTR_NAME_SELINUX, 1306 context, len); 1307 } 1308 dput(dentry); 1309 if (rc < 0) { 1310 if (rc != -ENODATA) { 1311 printk(KERN_WARNING "SELinux: %s: getxattr returned " 1312 "%d for dev=%s ino=%ld\n", __func__, 1313 -rc, inode->i_sb->s_id, inode->i_ino); 1314 kfree(context); 1315 goto out_unlock; 1316 } 1317 /* Map ENODATA to the default file SID */ 1318 sid = sbsec->def_sid; 1319 rc = 0; 1320 } else { 1321 rc = security_context_to_sid_default(context, rc, &sid, 1322 sbsec->def_sid, 1323 GFP_NOFS); 1324 if (rc) { 1325 char *dev = inode->i_sb->s_id; 1326 unsigned long ino = inode->i_ino; 1327 1328 if (rc == -EINVAL) { 1329 if (printk_ratelimit()) 1330 printk(KERN_NOTICE "SELinux: inode=%lu on dev=%s was found to have an invalid " 1331 "context=%s. This indicates you may need to relabel the inode or the " 1332 "filesystem in question.\n", ino, dev, context); 1333 } else { 1334 printk(KERN_WARNING "SELinux: %s: context_to_sid(%s) " 1335 "returned %d for dev=%s ino=%ld\n", 1336 __func__, context, -rc, dev, ino); 1337 } 1338 kfree(context); 1339 /* Leave with the unlabeled SID */ 1340 rc = 0; 1341 break; 1342 } 1343 } 1344 kfree(context); 1345 isec->sid = sid; 1346 break; 1347 case SECURITY_FS_USE_TASK: 1348 isec->sid = isec->task_sid; 1349 break; 1350 case SECURITY_FS_USE_TRANS: 1351 /* Default to the fs SID. */ 1352 isec->sid = sbsec->sid; 1353 1354 /* Try to obtain a transition SID. */ 1355 isec->sclass = inode_mode_to_security_class(inode->i_mode); 1356 rc = security_transition_sid(isec->task_sid, 1357 sbsec->sid, 1358 isec->sclass, 1359 &sid); 1360 if (rc) 1361 goto out_unlock; 1362 isec->sid = sid; 1363 break; 1364 case SECURITY_FS_USE_MNTPOINT: 1365 isec->sid = sbsec->mntpoint_sid; 1366 break; 1367 default: 1368 /* Default to the fs superblock SID. */ 1369 isec->sid = sbsec->sid; 1370 1371 if ((sbsec->flags & SE_SBPROC) && !S_ISLNK(inode->i_mode)) { 1372 struct proc_inode *proci = PROC_I(inode); 1373 if (proci->pde) { 1374 isec->sclass = inode_mode_to_security_class(inode->i_mode); 1375 rc = selinux_proc_get_sid(proci->pde, 1376 isec->sclass, 1377 &sid); 1378 if (rc) 1379 goto out_unlock; 1380 isec->sid = sid; 1381 } 1382 } 1383 break; 1384 } 1385 1386 isec->initialized = 1; 1387 1388out_unlock: 1389 mutex_unlock(&isec->lock); 1390out: 1391 if (isec->sclass == SECCLASS_FILE) 1392 isec->sclass = inode_mode_to_security_class(inode->i_mode); 1393 return rc; 1394} 1395 1396/* Convert a Linux signal to an access vector. */ 1397static inline u32 signal_to_av(int sig) 1398{ 1399 u32 perm = 0; 1400 1401 switch (sig) { 1402 case SIGCHLD: 1403 /* Commonly granted from child to parent. */ 1404 perm = PROCESS__SIGCHLD; 1405 break; 1406 case SIGKILL: 1407 /* Cannot be caught or ignored */ 1408 perm = PROCESS__SIGKILL; 1409 break; 1410 case SIGSTOP: 1411 /* Cannot be caught or ignored */ 1412 perm = PROCESS__SIGSTOP; 1413 break; 1414 default: 1415 /* All other signals. */ 1416 perm = PROCESS__SIGNAL; 1417 break; 1418 } 1419 1420 return perm; 1421} 1422 1423/* 1424 * Check permission between a pair of credentials 1425 * fork check, ptrace check, etc. 1426 */ 1427static int cred_has_perm(const struct cred *actor, 1428 const struct cred *target, 1429 u32 perms) 1430{ 1431 u32 asid = cred_sid(actor), tsid = cred_sid(target); 1432 1433 return avc_has_perm(asid, tsid, SECCLASS_PROCESS, perms, NULL); 1434} 1435 1436/* 1437 * Check permission between a pair of tasks, e.g. signal checks, 1438 * fork check, ptrace check, etc. 1439 * tsk1 is the actor and tsk2 is the target 1440 * - this uses the default subjective creds of tsk1 1441 */ 1442static int task_has_perm(const struct task_struct *tsk1, 1443 const struct task_struct *tsk2, 1444 u32 perms) 1445{ 1446 const struct task_security_struct *__tsec1, *__tsec2; 1447 u32 sid1, sid2; 1448 1449 rcu_read_lock(); 1450 __tsec1 = __task_cred(tsk1)->security; sid1 = __tsec1->sid; 1451 __tsec2 = __task_cred(tsk2)->security; sid2 = __tsec2->sid; 1452 rcu_read_unlock(); 1453 return avc_has_perm(sid1, sid2, SECCLASS_PROCESS, perms, NULL); 1454} 1455 1456/* 1457 * Check permission between current and another task, e.g. signal checks, 1458 * fork check, ptrace check, etc. 1459 * current is the actor and tsk2 is the target 1460 * - this uses current's subjective creds 1461 */ 1462static int current_has_perm(const struct task_struct *tsk, 1463 u32 perms) 1464{ 1465 u32 sid, tsid; 1466 1467 sid = current_sid(); 1468 tsid = task_sid(tsk); 1469 return avc_has_perm(sid, tsid, SECCLASS_PROCESS, perms, NULL); 1470} 1471 1472#if CAP_LAST_CAP > 63 1473#error Fix SELinux to handle capabilities > 63. 1474#endif 1475 1476/* Check whether a task is allowed to use a capability. */ 1477static int task_has_capability(struct task_struct *tsk, 1478 const struct cred *cred, 1479 int cap, int audit) 1480{ 1481 struct avc_audit_data ad; 1482 struct av_decision avd; 1483 u16 sclass; 1484 u32 sid = cred_sid(cred); 1485 u32 av = CAP_TO_MASK(cap); 1486 int rc; 1487 1488 AVC_AUDIT_DATA_INIT(&ad, CAP); 1489 ad.tsk = tsk; 1490 ad.u.cap = cap; 1491 1492 switch (CAP_TO_INDEX(cap)) { 1493 case 0: 1494 sclass = SECCLASS_CAPABILITY; 1495 break; 1496 case 1: 1497 sclass = SECCLASS_CAPABILITY2; 1498 break; 1499 default: 1500 printk(KERN_ERR 1501 "SELinux: out of range capability %d\n", cap); 1502 BUG(); 1503 } 1504 1505 rc = avc_has_perm_noaudit(sid, sid, sclass, av, 0, &avd); 1506 if (audit == SECURITY_CAP_AUDIT) 1507 avc_audit(sid, sid, sclass, av, &avd, rc, &ad); 1508 return rc; 1509} 1510 1511/* Check whether a task is allowed to use a system operation. */ 1512static int task_has_system(struct task_struct *tsk, 1513 u32 perms) 1514{ 1515 u32 sid = task_sid(tsk); 1516 1517 return avc_has_perm(sid, SECINITSID_KERNEL, 1518 SECCLASS_SYSTEM, perms, NULL); 1519} 1520 1521/* Check whether a task has a particular permission to an inode. 1522 The 'adp' parameter is optional and allows other audit 1523 data to be passed (e.g. the dentry). */ 1524static int inode_has_perm(const struct cred *cred, 1525 struct inode *inode, 1526 u32 perms, 1527 struct avc_audit_data *adp) 1528{ 1529 struct inode_security_struct *isec; 1530 struct avc_audit_data ad; 1531 u32 sid; 1532 1533 if (unlikely(IS_PRIVATE(inode))) 1534 return 0; 1535 1536 sid = cred_sid(cred); 1537 isec = inode->i_security; 1538 1539 if (!adp) { 1540 adp = &ad; 1541 AVC_AUDIT_DATA_INIT(&ad, FS); 1542 ad.u.fs.inode = inode; 1543 } 1544 1545 return avc_has_perm(sid, isec->sid, isec->sclass, perms, adp); 1546} 1547 1548/* Same as inode_has_perm, but pass explicit audit data containing 1549 the dentry to help the auditing code to more easily generate the 1550 pathname if needed. */ 1551static inline int dentry_has_perm(const struct cred *cred, 1552 struct vfsmount *mnt, 1553 struct dentry *dentry, 1554 u32 av) 1555{ 1556 struct inode *inode = dentry->d_inode; 1557 struct avc_audit_data ad; 1558 1559 AVC_AUDIT_DATA_INIT(&ad, FS); 1560 ad.u.fs.path.mnt = mnt; 1561 ad.u.fs.path.dentry = dentry; 1562 return inode_has_perm(cred, inode, av, &ad); 1563} 1564 1565/* Check whether a task can use an open file descriptor to 1566 access an inode in a given way. Check access to the 1567 descriptor itself, and then use dentry_has_perm to 1568 check a particular permission to the file. 1569 Access to the descriptor is implicitly granted if it 1570 has the same SID as the process. If av is zero, then 1571 access to the file is not checked, e.g. for cases 1572 where only the descriptor is affected like seek. */ 1573static int file_has_perm(const struct cred *cred, 1574 struct file *file, 1575 u32 av) 1576{ 1577 struct file_security_struct *fsec = file->f_security; 1578 struct inode *inode = file->f_path.dentry->d_inode; 1579 struct avc_audit_data ad; 1580 u32 sid = cred_sid(cred); 1581 int rc; 1582 1583 AVC_AUDIT_DATA_INIT(&ad, FS); 1584 ad.u.fs.path = file->f_path; 1585 1586 if (sid != fsec->sid) { 1587 rc = avc_has_perm(sid, fsec->sid, 1588 SECCLASS_FD, 1589 FD__USE, 1590 &ad); 1591 if (rc) 1592 goto out; 1593 } 1594 1595 /* av is zero if only checking access to the descriptor. */ 1596 rc = 0; 1597 if (av) 1598 rc = inode_has_perm(cred, inode, av, &ad); 1599 1600out: 1601 return rc; 1602} 1603 1604/* Check whether a task can create a file. */ 1605static int may_create(struct inode *dir, 1606 struct dentry *dentry, 1607 u16 tclass) 1608{ 1609 const struct cred *cred = current_cred(); 1610 const struct task_security_struct *tsec = cred->security; 1611 struct inode_security_struct *dsec; 1612 struct superblock_security_struct *sbsec; 1613 u32 sid, newsid; 1614 struct avc_audit_data ad; 1615 int rc; 1616 1617 dsec = dir->i_security; 1618 sbsec = dir->i_sb->s_security; 1619 1620 sid = tsec->sid; 1621 newsid = tsec->create_sid; 1622 1623 AVC_AUDIT_DATA_INIT(&ad, FS); 1624 ad.u.fs.path.dentry = dentry; 1625 1626 rc = avc_has_perm(sid, dsec->sid, SECCLASS_DIR, 1627 DIR__ADD_NAME | DIR__SEARCH, 1628 &ad); 1629 if (rc) 1630 return rc; 1631 1632 if (!newsid || !(sbsec->flags & SE_SBLABELSUPP)) { 1633 rc = security_transition_sid(sid, dsec->sid, tclass, &newsid); 1634 if (rc) 1635 return rc; 1636 } 1637 1638 rc = avc_has_perm(sid, newsid, tclass, FILE__CREATE, &ad); 1639 if (rc) 1640 return rc; 1641 1642 return avc_has_perm(newsid, sbsec->sid, 1643 SECCLASS_FILESYSTEM, 1644 FILESYSTEM__ASSOCIATE, &ad); 1645} 1646 1647/* Check whether a task can create a key. */ 1648static int may_create_key(u32 ksid, 1649 struct task_struct *ctx) 1650{ 1651 u32 sid = task_sid(ctx); 1652 1653 return avc_has_perm(sid, ksid, SECCLASS_KEY, KEY__CREATE, NULL); 1654} 1655 1656#define MAY_LINK 0 1657#define MAY_UNLINK 1 1658#define MAY_RMDIR 2 1659 1660/* Check whether a task can link, unlink, or rmdir a file/directory. */ 1661static int may_link(struct inode *dir, 1662 struct dentry *dentry, 1663 int kind) 1664 1665{ 1666 struct inode_security_struct *dsec, *isec; 1667 struct avc_audit_data ad; 1668 u32 sid = current_sid(); 1669 u32 av; 1670 int rc; 1671 1672 dsec = dir->i_security; 1673 isec = dentry->d_inode->i_security; 1674 1675 AVC_AUDIT_DATA_INIT(&ad, FS); 1676 ad.u.fs.path.dentry = dentry; 1677 1678 av = DIR__SEARCH; 1679 av |= (kind ? DIR__REMOVE_NAME : DIR__ADD_NAME); 1680 rc = avc_has_perm(sid, dsec->sid, SECCLASS_DIR, av, &ad); 1681 if (rc) 1682 return rc; 1683 1684 switch (kind) { 1685 case MAY_LINK: 1686 av = FILE__LINK; 1687 break; 1688 case MAY_UNLINK: 1689 av = FILE__UNLINK; 1690 break; 1691 case MAY_RMDIR: 1692 av = DIR__RMDIR; 1693 break; 1694 default: 1695 printk(KERN_WARNING "SELinux: %s: unrecognized kind %d\n", 1696 __func__, kind); 1697 return 0; 1698 } 1699 1700 rc = avc_has_perm(sid, isec->sid, isec->sclass, av, &ad); 1701 return rc; 1702} 1703 1704static inline int may_rename(struct inode *old_dir, 1705 struct dentry *old_dentry, 1706 struct inode *new_dir, 1707 struct dentry *new_dentry) 1708{ 1709 struct inode_security_struct *old_dsec, *new_dsec, *old_isec, *new_isec; 1710 struct avc_audit_data ad; 1711 u32 sid = current_sid(); 1712 u32 av; 1713 int old_is_dir, new_is_dir; 1714 int rc; 1715 1716 old_dsec = old_dir->i_security; 1717 old_isec = old_dentry->d_inode->i_security; 1718 old_is_dir = S_ISDIR(old_dentry->d_inode->i_mode); 1719 new_dsec = new_dir->i_security; 1720 1721 AVC_AUDIT_DATA_INIT(&ad, FS); 1722 1723 ad.u.fs.path.dentry = old_dentry; 1724 rc = avc_has_perm(sid, old_dsec->sid, SECCLASS_DIR, 1725 DIR__REMOVE_NAME | DIR__SEARCH, &ad); 1726 if (rc) 1727 return rc; 1728 rc = avc_has_perm(sid, old_isec->sid, 1729 old_isec->sclass, FILE__RENAME, &ad); 1730 if (rc) 1731 return rc; 1732 if (old_is_dir && new_dir != old_dir) { 1733 rc = avc_has_perm(sid, old_isec->sid, 1734 old_isec->sclass, DIR__REPARENT, &ad); 1735 if (rc) 1736 return rc; 1737 } 1738 1739 ad.u.fs.path.dentry = new_dentry; 1740 av = DIR__ADD_NAME | DIR__SEARCH; 1741 if (new_dentry->d_inode) 1742 av |= DIR__REMOVE_NAME; 1743 rc = avc_has_perm(sid, new_dsec->sid, SECCLASS_DIR, av, &ad); 1744 if (rc) 1745 return rc; 1746 if (new_dentry->d_inode) { 1747 new_isec = new_dentry->d_inode->i_security; 1748 new_is_dir = S_ISDIR(new_dentry->d_inode->i_mode); 1749 rc = avc_has_perm(sid, new_isec->sid, 1750 new_isec->sclass, 1751 (new_is_dir ? DIR__RMDIR : FILE__UNLINK), &ad); 1752 if (rc) 1753 return rc; 1754 } 1755 1756 return 0; 1757} 1758 1759/* Check whether a task can perform a filesystem operation. */ 1760static int superblock_has_perm(const struct cred *cred, 1761 struct super_block *sb, 1762 u32 perms, 1763 struct avc_audit_data *ad) 1764{ 1765 struct superblock_security_struct *sbsec; 1766 u32 sid = cred_sid(cred); 1767 1768 sbsec = sb->s_security; 1769 return avc_has_perm(sid, sbsec->sid, SECCLASS_FILESYSTEM, perms, ad); 1770} 1771 1772/* Convert a Linux mode and permission mask to an access vector. */ 1773static inline u32 file_mask_to_av(int mode, int mask) 1774{ 1775 u32 av = 0; 1776 1777 if ((mode & S_IFMT) != S_IFDIR) { 1778 if (mask & MAY_EXEC) 1779 av |= FILE__EXECUTE; 1780 if (mask & MAY_READ) 1781 av |= FILE__READ; 1782 1783 if (mask & MAY_APPEND) 1784 av |= FILE__APPEND; 1785 else if (mask & MAY_WRITE) 1786 av |= FILE__WRITE; 1787 1788 } else { 1789 if (mask & MAY_EXEC) 1790 av |= DIR__SEARCH; 1791 if (mask & MAY_WRITE) 1792 av |= DIR__WRITE; 1793 if (mask & MAY_READ) 1794 av |= DIR__READ; 1795 } 1796 1797 return av; 1798} 1799 1800/* Convert a Linux file to an access vector. */ 1801static inline u32 file_to_av(struct file *file) 1802{ 1803 u32 av = 0; 1804 1805 if (file->f_mode & FMODE_READ) 1806 av |= FILE__READ; 1807 if (file->f_mode & FMODE_WRITE) { 1808 if (file->f_flags & O_APPEND) 1809 av |= FILE__APPEND; 1810 else 1811 av |= FILE__WRITE; 1812 } 1813 if (!av) { 1814 /* 1815 * Special file opened with flags 3 for ioctl-only use. 1816 */ 1817 av = FILE__IOCTL; 1818 } 1819 1820 return av; 1821} 1822 1823/* 1824 * Convert a file to an access vector and include the correct open 1825 * open permission. 1826 */ 1827static inline u32 open_file_to_av(struct file *file) 1828{ 1829 u32 av = file_to_av(file); 1830 1831 if (selinux_policycap_openperm) { 1832 mode_t mode = file->f_path.dentry->d_inode->i_mode; 1833 /* 1834 * lnk files and socks do not really have an 'open' 1835 */ 1836 if (S_ISREG(mode)) 1837 av |= FILE__OPEN; 1838 else if (S_ISCHR(mode)) 1839 av |= CHR_FILE__OPEN; 1840 else if (S_ISBLK(mode)) 1841 av |= BLK_FILE__OPEN; 1842 else if (S_ISFIFO(mode)) 1843 av |= FIFO_FILE__OPEN; 1844 else if (S_ISDIR(mode)) 1845 av |= DIR__OPEN; 1846 else if (S_ISSOCK(mode)) 1847 av |= SOCK_FILE__OPEN; 1848 else 1849 printk(KERN_ERR "SELinux: WARNING: inside %s with " 1850 "unknown mode:%o\n", __func__, mode); 1851 } 1852 return av; 1853} 1854 1855/* Hook functions begin here. */ 1856 1857static int selinux_ptrace_access_check(struct task_struct *child, 1858 unsigned int mode) 1859{ 1860 int rc; 1861 1862 rc = cap_ptrace_access_check(child, mode); 1863 if (rc) 1864 return rc; 1865 1866 if (mode == PTRACE_MODE_READ) { 1867 u32 sid = current_sid(); 1868 u32 csid = task_sid(child); 1869 return avc_has_perm(sid, csid, SECCLASS_FILE, FILE__READ, NULL); 1870 } 1871 1872 return current_has_perm(child, PROCESS__PTRACE); 1873} 1874 1875static int selinux_ptrace_traceme(struct task_struct *parent) 1876{ 1877 int rc; 1878 1879 rc = cap_ptrace_traceme(parent); 1880 if (rc) 1881 return rc; 1882 1883 return task_has_perm(parent, current, PROCESS__PTRACE); 1884} 1885 1886static int selinux_capget(struct task_struct *target, kernel_cap_t *effective, 1887 kernel_cap_t *inheritable, kernel_cap_t *permitted) 1888{ 1889 int error; 1890 1891 error = current_has_perm(target, PROCESS__GETCAP); 1892 if (error) 1893 return error; 1894 1895 return cap_capget(target, effective, inheritable, permitted); 1896} 1897 1898static int selinux_capset(struct cred *new, const struct cred *old, 1899 const kernel_cap_t *effective, 1900 const kernel_cap_t *inheritable, 1901 const kernel_cap_t *permitted) 1902{ 1903 int error; 1904 1905 error = cap_capset(new, old, 1906 effective, inheritable, permitted); 1907 if (error) 1908 return error; 1909 1910 return cred_has_perm(old, new, PROCESS__SETCAP); 1911} 1912 1913/* 1914 * (This comment used to live with the selinux_task_setuid hook, 1915 * which was removed). 1916 * 1917 * Since setuid only affects the current process, and since the SELinux 1918 * controls are not based on the Linux identity attributes, SELinux does not 1919 * need to control this operation. However, SELinux does control the use of 1920 * the CAP_SETUID and CAP_SETGID capabilities using the capable hook. 1921 */ 1922 1923static int selinux_capable(struct task_struct *tsk, const struct cred *cred, 1924 int cap, int audit) 1925{ 1926 int rc; 1927 1928 rc = cap_capable(tsk, cred, cap, audit); 1929 if (rc) 1930 return rc; 1931 1932 return task_has_capability(tsk, cred, cap, audit); 1933} 1934 1935static int selinux_sysctl_get_sid(ctl_table *table, u16 tclass, u32 *sid) 1936{ 1937 int buflen, rc; 1938 char *buffer, *path, *end; 1939 1940 rc = -ENOMEM; 1941 buffer = (char *)__get_free_page(GFP_KERNEL); 1942 if (!buffer) 1943 goto out; 1944 1945 buflen = PAGE_SIZE; 1946 end = buffer+buflen; 1947 *--end = '\0'; 1948 buflen--; 1949 path = end-1; 1950 *path = '/'; 1951 while (table) { 1952 const char *name = table->procname; 1953 size_t namelen = strlen(name); 1954 buflen -= namelen + 1; 1955 if (buflen < 0) 1956 goto out_free; 1957 end -= namelen; 1958 memcpy(end, name, namelen); 1959 *--end = '/'; 1960 path = end; 1961 table = table->parent; 1962 } 1963 buflen -= 4; 1964 if (buflen < 0) 1965 goto out_free; 1966 end -= 4; 1967 memcpy(end, "/sys", 4); 1968 path = end; 1969 rc = security_genfs_sid("proc", path, tclass, sid); 1970out_free: 1971 free_page((unsigned long)buffer); 1972out: 1973 return rc; 1974} 1975 1976static int selinux_sysctl(ctl_table *table, int op) 1977{ 1978 int error = 0; 1979 u32 av; 1980 u32 tsid, sid; 1981 int rc; 1982 1983 sid = current_sid(); 1984 1985 rc = selinux_sysctl_get_sid(table, (op == 0001) ? 1986 SECCLASS_DIR : SECCLASS_FILE, &tsid); 1987 if (rc) { 1988 /* Default to the well-defined sysctl SID. */ 1989 tsid = SECINITSID_SYSCTL; 1990 } 1991 1992 /* The op values are "defined" in sysctl.c, thereby creating 1993 * a bad coupling between this module and sysctl.c */ 1994 if (op == 001) { 1995 error = avc_has_perm(sid, tsid, 1996 SECCLASS_DIR, DIR__SEARCH, NULL); 1997 } else { 1998 av = 0; 1999 if (op & 004) 2000 av |= FILE__READ; 2001 if (op & 002) 2002 av |= FILE__WRITE; 2003 if (av) 2004 error = avc_has_perm(sid, tsid, 2005 SECCLASS_FILE, av, NULL); 2006 } 2007 2008 return error; 2009} 2010 2011static int selinux_quotactl(int cmds, int type, int id, struct super_block *sb) 2012{ 2013 const struct cred *cred = current_cred(); 2014 int rc = 0; 2015 2016 if (!sb) 2017 return 0; 2018 2019 switch (cmds) { 2020 case Q_SYNC: 2021 case Q_QUOTAON: 2022 case Q_QUOTAOFF: 2023 case Q_SETINFO: 2024 case Q_SETQUOTA: 2025 rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAMOD, NULL); 2026 break; 2027 case Q_GETFMT: 2028 case Q_GETINFO: 2029 case Q_GETQUOTA: 2030 rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAGET, NULL); 2031 break; 2032 default: 2033 rc = 0; /* let the kernel handle invalid cmds */ 2034 break; 2035 } 2036 return rc; 2037} 2038 2039static int selinux_quota_on(struct dentry *dentry) 2040{ 2041 const struct cred *cred = current_cred(); 2042 2043 return dentry_has_perm(cred, NULL, dentry, FILE__QUOTAON); 2044} 2045 2046static int selinux_syslog(int type) 2047{ 2048 int rc; 2049 2050 rc = cap_syslog(type); 2051 if (rc) 2052 return rc; 2053 2054 switch (type) { 2055 case 3: /* Read last kernel messages */ 2056 case 10: /* Return size of the log buffer */ 2057 rc = task_has_system(current, SYSTEM__SYSLOG_READ); 2058 break; 2059 case 6: /* Disable logging to console */ 2060 case 7: /* Enable logging to console */ 2061 case 8: /* Set level of messages printed to console */ 2062 rc = task_has_system(current, SYSTEM__SYSLOG_CONSOLE); 2063 break; 2064 case 0: /* Close log */ 2065 case 1: /* Open log */ 2066 case 2: /* Read from log */ 2067 case 4: /* Read/clear last kernel messages */ 2068 case 5: /* Clear ring buffer */ 2069 default: 2070 rc = task_has_system(current, SYSTEM__SYSLOG_MOD); 2071 break; 2072 } 2073 return rc; 2074} 2075 2076/* 2077 * Check that a process has enough memory to allocate a new virtual 2078 * mapping. 0 means there is enough memory for the allocation to 2079 * succeed and -ENOMEM implies there is not. 2080 * 2081 * Do not audit the selinux permission check, as this is applied to all 2082 * processes that allocate mappings. 2083 */ 2084static int selinux_vm_enough_memory(struct mm_struct *mm, long pages) 2085{ 2086 int rc, cap_sys_admin = 0; 2087 2088 rc = selinux_capable(current, current_cred(), CAP_SYS_ADMIN, 2089 SECURITY_CAP_NOAUDIT); 2090 if (rc == 0) 2091 cap_sys_admin = 1; 2092 2093 return __vm_enough_memory(mm, pages, cap_sys_admin); 2094} 2095 2096/* binprm security operations */ 2097 2098static int selinux_bprm_set_creds(struct linux_binprm *bprm) 2099{ 2100 const struct task_security_struct *old_tsec; 2101 struct task_security_struct *new_tsec; 2102 struct inode_security_struct *isec; 2103 struct avc_audit_data ad; 2104 struct inode *inode = bprm->file->f_path.dentry->d_inode; 2105 int rc; 2106 2107 rc = cap_bprm_set_creds(bprm); 2108 if (rc) 2109 return rc; 2110 2111 /* SELinux context only depends on initial program or script and not 2112 * the script interpreter */ 2113 if (bprm->cred_prepared) 2114 return 0; 2115 2116 old_tsec = current_security(); 2117 new_tsec = bprm->cred->security; 2118 isec = inode->i_security; 2119 2120 /* Default to the current task SID. */ 2121 new_tsec->sid = old_tsec->sid; 2122 new_tsec->osid = old_tsec->sid; 2123 2124 /* Reset fs, key, and sock SIDs on execve. */ 2125 new_tsec->create_sid = 0; 2126 new_tsec->keycreate_sid = 0; 2127 new_tsec->sockcreate_sid = 0; 2128 2129 if (old_tsec->exec_sid) { 2130 new_tsec->sid = old_tsec->exec_sid; 2131 /* Reset exec SID on execve. */ 2132 new_tsec->exec_sid = 0; 2133 } else { 2134 /* Check for a default transition on this program. */ 2135 rc = security_transition_sid(old_tsec->sid, isec->sid, 2136 SECCLASS_PROCESS, &new_tsec->sid); 2137 if (rc) 2138 return rc; 2139 } 2140 2141 AVC_AUDIT_DATA_INIT(&ad, FS); 2142 ad.u.fs.path = bprm->file->f_path; 2143 2144 if (bprm->file->f_path.mnt->mnt_flags & MNT_NOSUID) 2145 new_tsec->sid = old_tsec->sid; 2146 2147 if (new_tsec->sid == old_tsec->sid) { 2148 rc = avc_has_perm(old_tsec->sid, isec->sid, 2149 SECCLASS_FILE, FILE__EXECUTE_NO_TRANS, &ad); 2150 if (rc) 2151 return rc; 2152 } else { 2153 /* Check permissions for the transition. */ 2154 rc = avc_has_perm(old_tsec->sid, new_tsec->sid, 2155 SECCLASS_PROCESS, PROCESS__TRANSITION, &ad); 2156 if (rc) 2157 return rc; 2158 2159 rc = avc_has_perm(new_tsec->sid, isec->sid, 2160 SECCLASS_FILE, FILE__ENTRYPOINT, &ad); 2161 if (rc) 2162 return rc; 2163 2164 /* Check for shared state */ 2165 if (bprm->unsafe & LSM_UNSAFE_SHARE) { 2166 rc = avc_has_perm(old_tsec->sid, new_tsec->sid, 2167 SECCLASS_PROCESS, PROCESS__SHARE, 2168 NULL); 2169 if (rc) 2170 return -EPERM; 2171 } 2172 2173 /* Make sure that anyone attempting to ptrace over a task that 2174 * changes its SID has the appropriate permit */ 2175 if (bprm->unsafe & 2176 (LSM_UNSAFE_PTRACE | LSM_UNSAFE_PTRACE_CAP)) { 2177 struct task_struct *tracer; 2178 struct task_security_struct *sec; 2179 u32 ptsid = 0; 2180 2181 rcu_read_lock(); 2182 tracer = tracehook_tracer_task(current); 2183 if (likely(tracer != NULL)) { 2184 sec = __task_cred(tracer)->security; 2185 ptsid = sec->sid; 2186 } 2187 rcu_read_unlock(); 2188 2189 if (ptsid != 0) { 2190 rc = avc_has_perm(ptsid, new_tsec->sid, 2191 SECCLASS_PROCESS, 2192 PROCESS__PTRACE, NULL); 2193 if (rc) 2194 return -EPERM; 2195 } 2196 } 2197 2198 /* Clear any possibly unsafe personality bits on exec: */ 2199 bprm->per_clear |= PER_CLEAR_ON_SETID; 2200 } 2201 2202 return 0; 2203} 2204 2205static int selinux_bprm_secureexec(struct linux_binprm *bprm) 2206{ 2207 const struct cred *cred = current_cred(); 2208 const struct task_security_struct *tsec = cred->security; 2209 u32 sid, osid; 2210 int atsecure = 0; 2211 2212 sid = tsec->sid; 2213 osid = tsec->osid; 2214 2215 if (osid != sid) { 2216 /* Enable secure mode for SIDs transitions unless 2217 the noatsecure permission is granted between 2218 the two SIDs, i.e. ahp returns 0. */ 2219 atsecure = avc_has_perm(osid, sid, 2220 SECCLASS_PROCESS, 2221 PROCESS__NOATSECURE, NULL); 2222 } 2223 2224 return (atsecure || cap_bprm_secureexec(bprm)); 2225} 2226 2227extern struct vfsmount *selinuxfs_mount; 2228extern struct dentry *selinux_null; 2229 2230/* Derived from fs/exec.c:flush_old_files. */ 2231static inline void flush_unauthorized_files(const struct cred *cred, 2232 struct files_struct *files) 2233{ 2234 struct avc_audit_data ad; 2235 struct file *file, *devnull = NULL; 2236 struct tty_struct *tty; 2237 struct fdtable *fdt; 2238 long j = -1; 2239 int drop_tty = 0; 2240 2241 tty = get_current_tty(); 2242 if (tty) { 2243 file_list_lock(); 2244 if (!list_empty(&tty->tty_files)) { 2245 struct inode *inode; 2246 2247 /* Revalidate access to controlling tty. 2248 Use inode_has_perm on the tty inode directly rather 2249 than using file_has_perm, as this particular open 2250 file may belong to another process and we are only 2251 interested in the inode-based check here. */ 2252 file = list_first_entry(&tty->tty_files, struct file, f_u.fu_list); 2253 inode = file->f_path.dentry->d_inode; 2254 if (inode_has_perm(cred, inode, 2255 FILE__READ | FILE__WRITE, NULL)) { 2256 drop_tty = 1; 2257 } 2258 } 2259 file_list_unlock(); 2260 tty_kref_put(tty); 2261 } 2262 /* Reset controlling tty. */ 2263 if (drop_tty) 2264 no_tty(); 2265 2266 /* Revalidate access to inherited open files. */ 2267 2268 AVC_AUDIT_DATA_INIT(&ad, FS); 2269 2270 spin_lock(&files->file_lock); 2271 for (;;) { 2272 unsigned long set, i; 2273 int fd; 2274 2275 j++; 2276 i = j * __NFDBITS; 2277 fdt = files_fdtable(files); 2278 if (i >= fdt->max_fds) 2279 break; 2280 set = fdt->open_fds->fds_bits[j]; 2281 if (!set) 2282 continue; 2283 spin_unlock(&files->file_lock); 2284 for ( ; set ; i++, set >>= 1) { 2285 if (set & 1) { 2286 file = fget(i); 2287 if (!file) 2288 continue; 2289 if (file_has_perm(cred, 2290 file, 2291 file_to_av(file))) { 2292 sys_close(i); 2293 fd = get_unused_fd(); 2294 if (fd != i) { 2295 if (fd >= 0) 2296 put_unused_fd(fd); 2297 fput(file); 2298 continue; 2299 } 2300 if (devnull) { 2301 get_file(devnull); 2302 } else { 2303 devnull = dentry_open( 2304 dget(selinux_null), 2305 mntget(selinuxfs_mount), 2306 O_RDWR, cred); 2307 if (IS_ERR(devnull)) { 2308 devnull = NULL; 2309 put_unused_fd(fd); 2310 fput(file); 2311 continue; 2312 } 2313 } 2314 fd_install(fd, devnull); 2315 } 2316 fput(file); 2317 } 2318 } 2319 spin_lock(&files->file_lock); 2320 2321 } 2322 spin_unlock(&files->file_lock); 2323} 2324 2325/* 2326 * Prepare a process for imminent new credential changes due to exec 2327 */ 2328static void selinux_bprm_committing_creds(struct linux_binprm *bprm) 2329{ 2330 struct task_security_struct *new_tsec; 2331 struct rlimit *rlim, *initrlim; 2332 int rc, i; 2333 2334 new_tsec = bprm->cred->security; 2335 if (new_tsec->sid == new_tsec->osid) 2336 return; 2337 2338 /* Close files for which the new task SID is not authorized. */ 2339 flush_unauthorized_files(bprm->cred, current->files); 2340 2341 /* Always clear parent death signal on SID transitions. */ 2342 current->pdeath_signal = 0; 2343 2344 /* Check whether the new SID can inherit resource limits from the old 2345 * SID. If not, reset all soft limits to the lower of the current 2346 * task's hard limit and the init task's soft limit. 2347 * 2348 * Note that the setting of hard limits (even to lower them) can be 2349 * controlled by the setrlimit check. The inclusion of the init task's 2350 * soft limit into the computation is to avoid resetting soft limits 2351 * higher than the default soft limit for cases where the default is 2352 * lower than the hard limit, e.g. RLIMIT_CORE or RLIMIT_STACK. 2353 */ 2354 rc = avc_has_perm(new_tsec->osid, new_tsec->sid, SECCLASS_PROCESS, 2355 PROCESS__RLIMITINH, NULL); 2356 if (rc) { 2357 for (i = 0; i < RLIM_NLIMITS; i++) { 2358 rlim = current->signal->rlim + i; 2359 initrlim = init_task.signal->rlim + i; 2360 rlim->rlim_cur = min(rlim->rlim_max, initrlim->rlim_cur); 2361 } 2362 update_rlimit_cpu(rlim->rlim_cur); 2363 } 2364} 2365 2366/* 2367 * Clean up the process immediately after the installation of new credentials 2368 * due to exec 2369 */ 2370static void selinux_bprm_committed_creds(struct linux_binprm *bprm) 2371{ 2372 const struct task_security_struct *tsec = current_security(); 2373 struct itimerval itimer; 2374 u32 osid, sid; 2375 int rc, i; 2376 2377 osid = tsec->osid; 2378 sid = tsec->sid; 2379 2380 if (sid == osid) 2381 return; 2382 2383 /* Check whether the new SID can inherit signal state from the old SID. 2384 * If not, clear itimers to avoid subsequent signal generation and 2385 * flush and unblock signals. 2386 * 2387 * This must occur _after_ the task SID has been updated so that any 2388 * kill done after the flush will be checked against the new SID. 2389 */ 2390 rc = avc_has_perm(osid, sid, SECCLASS_PROCESS, PROCESS__SIGINH, NULL); 2391 if (rc) { 2392 memset(&itimer, 0, sizeof itimer); 2393 for (i = 0; i < 3; i++) 2394 do_setitimer(i, &itimer, NULL); 2395 spin_lock_irq(¤t->sighand->siglock); 2396 if (!(current->signal->flags & SIGNAL_GROUP_EXIT)) { 2397 __flush_signals(current); 2398 flush_signal_handlers(current, 1); 2399 sigemptyset(¤t->blocked); 2400 } 2401 spin_unlock_irq(¤t->sighand->siglock); 2402 } 2403 2404 /* Wake up the parent if it is waiting so that it can recheck 2405 * wait permission to the new task SID. */ 2406 read_lock(&tasklist_lock); 2407 wake_up_interruptible(¤t->real_parent->signal->wait_chldexit); 2408 read_unlock(&tasklist_lock); 2409} 2410 2411/* superblock security operations */ 2412 2413static int selinux_sb_alloc_security(struct super_block *sb) 2414{ 2415 return superblock_alloc_security(sb); 2416} 2417 2418static void selinux_sb_free_security(struct super_block *sb) 2419{ 2420 superblock_free_security(sb); 2421} 2422 2423static inline int match_prefix(char *prefix, int plen, char *option, int olen) 2424{ 2425 if (plen > olen) 2426 return 0; 2427 2428 return !memcmp(prefix, option, plen); 2429} 2430 2431static inline int selinux_option(char *option, int len) 2432{ 2433 return (match_prefix(CONTEXT_STR, sizeof(CONTEXT_STR)-1, option, len) || 2434 match_prefix(FSCONTEXT_STR, sizeof(FSCONTEXT_STR)-1, option, len) || 2435 match_prefix(DEFCONTEXT_STR, sizeof(DEFCONTEXT_STR)-1, option, len) || 2436 match_prefix(ROOTCONTEXT_STR, sizeof(ROOTCONTEXT_STR)-1, option, len) || 2437 match_prefix(LABELSUPP_STR, sizeof(LABELSUPP_STR)-1, option, len)); 2438} 2439 2440static inline void take_option(char **to, char *from, int *first, int len) 2441{ 2442 if (!*first) { 2443 **to = ','; 2444 *to += 1; 2445 } else 2446 *first = 0; 2447 memcpy(*to, from, len); 2448 *to += len; 2449} 2450 2451static inline void take_selinux_option(char **to, char *from, int *first, 2452 int len) 2453{ 2454 int current_size = 0; 2455 2456 if (!*first) { 2457 **to = '|'; 2458 *to += 1; 2459 } else 2460 *first = 0; 2461 2462 while (current_size < len) { 2463 if (*from != '"') { 2464 **to = *from; 2465 *to += 1; 2466 } 2467 from += 1; 2468 current_size += 1; 2469 } 2470} 2471 2472static int selinux_sb_copy_data(char *orig, char *copy) 2473{ 2474 int fnosec, fsec, rc = 0; 2475 char *in_save, *in_curr, *in_end; 2476 char *sec_curr, *nosec_save, *nosec; 2477 int open_quote = 0; 2478 2479 in_curr = orig; 2480 sec_curr = copy; 2481 2482 nosec = (char *)get_zeroed_page(GFP_KERNEL); 2483 if (!nosec) { 2484 rc = -ENOMEM; 2485 goto out; 2486 } 2487 2488 nosec_save = nosec; 2489 fnosec = fsec = 1; 2490 in_save = in_end = orig; 2491 2492 do { 2493 if (*in_end == '"') 2494 open_quote = !open_quote; 2495 if ((*in_end == ',' && open_quote == 0) || 2496 *in_end == '\0') { 2497 int len = in_end - in_curr; 2498 2499 if (selinux_option(in_curr, len)) 2500 take_selinux_option(&sec_curr, in_curr, &fsec, len); 2501 else 2502 take_option(&nosec, in_curr, &fnosec, len); 2503 2504 in_curr = in_end + 1; 2505 } 2506 } while (*in_end++); 2507 2508 strcpy(in_save, nosec_save); 2509 free_page((unsigned long)nosec_save); 2510out: 2511 return rc; 2512} 2513 2514static int selinux_sb_kern_mount(struct super_block *sb, int flags, void *data) 2515{ 2516 const struct cred *cred = current_cred(); 2517 struct avc_audit_data ad; 2518 int rc; 2519 2520 rc = superblock_doinit(sb, data); 2521 if (rc) 2522 return rc; 2523 2524 /* Allow all mounts performed by the kernel */ 2525 if (flags & MS_KERNMOUNT) 2526 return 0; 2527 2528 AVC_AUDIT_DATA_INIT(&ad, FS); 2529 ad.u.fs.path.dentry = sb->s_root; 2530 return superblock_has_perm(cred, sb, FILESYSTEM__MOUNT, &ad); 2531} 2532 2533static int selinux_sb_statfs(struct dentry *dentry) 2534{ 2535 const struct cred *cred = current_cred(); 2536 struct avc_audit_data ad; 2537 2538 AVC_AUDIT_DATA_INIT(&ad, FS); 2539 ad.u.fs.path.dentry = dentry->d_sb->s_root; 2540 return superblock_has_perm(cred, dentry->d_sb, FILESYSTEM__GETATTR, &ad); 2541} 2542 2543static int selinux_mount(char *dev_name, 2544 struct path *path, 2545 char *type, 2546 unsigned long flags, 2547 void *data) 2548{ 2549 const struct cred *cred = current_cred(); 2550 2551 if (flags & MS_REMOUNT) 2552 return superblock_has_perm(cred, path->mnt->mnt_sb, 2553 FILESYSTEM__REMOUNT, NULL); 2554 else 2555 return dentry_has_perm(cred, path->mnt, path->dentry, 2556 FILE__MOUNTON); 2557} 2558 2559static int selinux_umount(struct vfsmount *mnt, int flags) 2560{ 2561 const struct cred *cred = current_cred(); 2562 2563 return superblock_has_perm(cred, mnt->mnt_sb, 2564 FILESYSTEM__UNMOUNT, NULL); 2565} 2566 2567/* inode security operations */ 2568 2569static int selinux_inode_alloc_security(struct inode *inode) 2570{ 2571 return inode_alloc_security(inode); 2572} 2573 2574static void selinux_inode_free_security(struct inode *inode) 2575{ 2576 inode_free_security(inode); 2577} 2578 2579static int selinux_inode_init_security(struct inode *inode, struct inode *dir, 2580 char **name, void **value, 2581 size_t *len) 2582{ 2583 const struct cred *cred = current_cred(); 2584 const struct task_security_struct *tsec = cred->security; 2585 struct inode_security_struct *dsec; 2586 struct superblock_security_struct *sbsec; 2587 u32 sid, newsid, clen; 2588 int rc; 2589 char *namep = NULL, *context; 2590 2591 dsec = dir->i_security; 2592 sbsec = dir->i_sb->s_security; 2593 2594 sid = tsec->sid; 2595 newsid = tsec->create_sid; 2596 2597 if (!newsid || !(sbsec->flags & SE_SBLABELSUPP)) { 2598 rc = security_transition_sid(sid, dsec->sid, 2599 inode_mode_to_security_class(inode->i_mode), 2600 &newsid); 2601 if (rc) { 2602 printk(KERN_WARNING "%s: " 2603 "security_transition_sid failed, rc=%d (dev=%s " 2604 "ino=%ld)\n", 2605 __func__, 2606 -rc, inode->i_sb->s_id, inode->i_ino); 2607 return rc; 2608 } 2609 } 2610 2611 /* Possibly defer initialization to selinux_complete_init. */ 2612 if (sbsec->flags & SE_SBINITIALIZED) { 2613 struct inode_security_struct *isec = inode->i_security; 2614 isec->sclass = inode_mode_to_security_class(inode->i_mode); 2615 isec->sid = newsid; 2616 isec->initialized = 1; 2617 } 2618 2619 if (!ss_initialized || !(sbsec->flags & SE_SBLABELSUPP)) 2620 return -EOPNOTSUPP; 2621 2622 if (name) { 2623 namep = kstrdup(XATTR_SELINUX_SUFFIX, GFP_NOFS); 2624 if (!namep) 2625 return -ENOMEM; 2626 *name = namep; 2627 } 2628 2629 if (value && len) { 2630 rc = security_sid_to_context_force(newsid, &context, &clen); 2631 if (rc) { 2632 kfree(namep); 2633 return rc; 2634 } 2635 *value = context; 2636 *len = clen; 2637 } 2638 2639 return 0; 2640} 2641 2642static int selinux_inode_create(struct inode *dir, struct dentry *dentry, int mask) 2643{ 2644 return may_create(dir, dentry, SECCLASS_FILE); 2645} 2646 2647static int selinux_inode_link(struct dentry *old_dentry, struct inode *dir, struct dentry *new_dentry) 2648{ 2649 return may_link(dir, old_dentry, MAY_LINK); 2650} 2651 2652static int selinux_inode_unlink(struct inode *dir, struct dentry *dentry) 2653{ 2654 return may_link(dir, dentry, MAY_UNLINK); 2655} 2656 2657static int selinux_inode_symlink(struct inode *dir, struct dentry *dentry, const char *name) 2658{ 2659 return may_create(dir, dentry, SECCLASS_LNK_FILE); 2660} 2661 2662static int selinux_inode_mkdir(struct inode *dir, struct dentry *dentry, int mask) 2663{ 2664 return may_create(dir, dentry, SECCLASS_DIR); 2665} 2666 2667static int selinux_inode_rmdir(struct inode *dir, struct dentry *dentry) 2668{ 2669 return may_link(dir, dentry, MAY_RMDIR); 2670} 2671 2672static int selinux_inode_mknod(struct inode *dir, struct dentry *dentry, int mode, dev_t dev) 2673{ 2674 return may_create(dir, dentry, inode_mode_to_security_class(mode)); 2675} 2676 2677static int selinux_inode_rename(struct inode *old_inode, struct dentry *old_dentry, 2678 struct inode *new_inode, struct dentry *new_dentry) 2679{ 2680 return may_rename(old_inode, old_dentry, new_inode, new_dentry); 2681} 2682 2683static int selinux_inode_readlink(struct dentry *dentry) 2684{ 2685 const struct cred *cred = current_cred(); 2686 2687 return dentry_has_perm(cred, NULL, dentry, FILE__READ); 2688} 2689 2690static int selinux_inode_follow_link(struct dentry *dentry, struct nameidata *nameidata) 2691{ 2692 const struct cred *cred = current_cred(); 2693 2694 return dentry_has_perm(cred, NULL, dentry, FILE__READ); 2695} 2696 2697static int selinux_inode_permission(struct inode *inode, int mask) 2698{ 2699 const struct cred *cred = current_cred(); 2700 2701 if (!mask) { 2702 /* No permission to check. Existence test. */ 2703 return 0; 2704 } 2705 2706 return inode_has_perm(cred, inode, 2707 file_mask_to_av(inode->i_mode, mask), NULL); 2708} 2709 2710static int selinux_inode_setattr(struct dentry *dentry, struct iattr *iattr) 2711{ 2712 const struct cred *cred = current_cred(); 2713 2714 if (iattr->ia_valid & ATTR_FORCE) 2715 return 0; 2716 2717 if (iattr->ia_valid & (ATTR_MODE | ATTR_UID | ATTR_GID | 2718 ATTR_ATIME_SET | ATTR_MTIME_SET)) 2719 return dentry_has_perm(cred, NULL, dentry, FILE__SETATTR); 2720 2721 return dentry_has_perm(cred, NULL, dentry, FILE__WRITE); 2722} 2723 2724static int selinux_inode_getattr(struct vfsmount *mnt, struct dentry *dentry) 2725{ 2726 const struct cred *cred = current_cred(); 2727 2728 return dentry_has_perm(cred, mnt, dentry, FILE__GETATTR); 2729} 2730 2731static int selinux_inode_setotherxattr(struct dentry *dentry, const char *name) 2732{ 2733 const struct cred *cred = current_cred(); 2734 2735 if (!strncmp(name, XATTR_SECURITY_PREFIX, 2736 sizeof XATTR_SECURITY_PREFIX - 1)) { 2737 if (!strcmp(name, XATTR_NAME_CAPS)) { 2738 if (!capable(CAP_SETFCAP)) 2739 return -EPERM; 2740 } else if (!capable(CAP_SYS_ADMIN)) { 2741 /* A different attribute in the security namespace. 2742 Restrict to administrator. */ 2743 return -EPERM; 2744 } 2745 } 2746 2747 /* Not an attribute we recognize, so just check the 2748 ordinary setattr permission. */ 2749 return dentry_has_perm(cred, NULL, dentry, FILE__SETATTR); 2750} 2751 2752static int selinux_inode_setxattr(struct dentry *dentry, const char *name, 2753 const void *value, size_t size, int flags) 2754{ 2755 struct inode *inode = dentry->d_inode; 2756 struct inode_security_struct *isec = inode->i_security; 2757 struct superblock_security_struct *sbsec; 2758 struct avc_audit_data ad; 2759 u32 newsid, sid = current_sid(); 2760 int rc = 0; 2761 2762 if (strcmp(name, XATTR_NAME_SELINUX)) 2763 return selinux_inode_setotherxattr(dentry, name); 2764 2765 sbsec = inode->i_sb->s_security; 2766 if (!(sbsec->flags & SE_SBLABELSUPP)) 2767 return -EOPNOTSUPP; 2768 2769 if (!is_owner_or_cap(inode)) 2770 return -EPERM; 2771 2772 AVC_AUDIT_DATA_INIT(&ad, FS); 2773 ad.u.fs.path.dentry = dentry; 2774 2775 rc = avc_has_perm(sid, isec->sid, isec->sclass, 2776 FILE__RELABELFROM, &ad); 2777 if (rc) 2778 return rc; 2779 2780 rc = security_context_to_sid(value, size, &newsid); 2781 if (rc == -EINVAL) { 2782 if (!capable(CAP_MAC_ADMIN)) 2783 return rc; 2784 rc = security_context_to_sid_force(value, size, &newsid); 2785 } 2786 if (rc) 2787 return rc; 2788 2789 rc = avc_has_perm(sid, newsid, isec->sclass, 2790 FILE__RELABELTO, &ad); 2791 if (rc) 2792 return rc; 2793 2794 rc = security_validate_transition(isec->sid, newsid, sid, 2795 isec->sclass); 2796 if (rc) 2797 return rc; 2798 2799 return avc_has_perm(newsid, 2800 sbsec->sid, 2801 SECCLASS_FILESYSTEM, 2802 FILESYSTEM__ASSOCIATE, 2803 &ad); 2804} 2805 2806static void selinux_inode_post_setxattr(struct dentry *dentry, const char *name, 2807 const void *value, size_t size, 2808 int flags) 2809{ 2810 struct inode *inode = dentry->d_inode; 2811 struct inode_security_struct *isec = inode->i_security; 2812 u32 newsid; 2813 int rc; 2814 2815 if (strcmp(name, XATTR_NAME_SELINUX)) { 2816 /* Not an attribute we recognize, so nothing to do. */ 2817 return; 2818 } 2819 2820 rc = security_context_to_sid_force(value, size, &newsid); 2821 if (rc) { 2822 printk(KERN_ERR "SELinux: unable to map context to SID" 2823 "for (%s, %lu), rc=%d\n", 2824 inode->i_sb->s_id, inode->i_ino, -rc); 2825 return; 2826 } 2827 2828 isec->sid = newsid; 2829 return; 2830} 2831 2832static int selinux_inode_getxattr(struct dentry *dentry, const char *name) 2833{ 2834 const struct cred *cred = current_cred(); 2835 2836 return dentry_has_perm(cred, NULL, dentry, FILE__GETATTR); 2837} 2838 2839static int selinux_inode_listxattr(struct dentry *dentry) 2840{ 2841 const struct cred *cred = current_cred(); 2842 2843 return dentry_has_perm(cred, NULL, dentry, FILE__GETATTR); 2844} 2845 2846static int selinux_inode_removexattr(struct dentry *dentry, const char *name) 2847{ 2848 if (strcmp(name, XATTR_NAME_SELINUX)) 2849 return selinux_inode_setotherxattr(dentry, name); 2850 2851 /* No one is allowed to remove a SELinux security label. 2852 You can change the label, but all data must be labeled. */ 2853 return -EACCES; 2854} 2855 2856/* 2857 * Copy the inode security context value to the user. 2858 * 2859 * Permission check is handled by selinux_inode_getxattr hook. 2860 */ 2861static int selinux_inode_getsecurity(const struct inode *inode, const char *name, void **buffer, bool alloc) 2862{ 2863 u32 size; 2864 int error; 2865 char *context = NULL; 2866 struct inode_security_struct *isec = inode->i_security; 2867 2868 if (strcmp(name, XATTR_SELINUX_SUFFIX)) 2869 return -EOPNOTSUPP; 2870 2871 /* 2872 * If the caller has CAP_MAC_ADMIN, then get the raw context 2873 * value even if it is not defined by current policy; otherwise, 2874 * use the in-core value under current policy. 2875 * Use the non-auditing forms of the permission checks since 2876 * getxattr may be called by unprivileged processes commonly 2877 * and lack of permission just means that we fall back to the 2878 * in-core context value, not a denial. 2879 */ 2880 error = selinux_capable(current, current_cred(), CAP_MAC_ADMIN, 2881 SECURITY_CAP_NOAUDIT); 2882 if (!error) 2883 error = security_sid_to_context_force(isec->sid, &context, 2884 &size); 2885 else 2886 error = security_sid_to_context(isec->sid, &context, &size); 2887 if (error) 2888 return error; 2889 error = size; 2890 if (alloc) { 2891 *buffer = context; 2892 goto out_nofree; 2893 } 2894 kfree(context); 2895out_nofree: 2896 return error; 2897} 2898 2899static int selinux_inode_setsecurity(struct inode *inode, const char *name, 2900 const void *value, size_t size, int flags) 2901{ 2902 struct inode_security_struct *isec = inode->i_security; 2903 u32 newsid; 2904 int rc; 2905 2906 if (strcmp(name, XATTR_SELINUX_SUFFIX)) 2907 return -EOPNOTSUPP; 2908 2909 if (!value || !size) 2910 return -EACCES; 2911 2912 rc = security_context_to_sid((void *)value, size, &newsid); 2913 if (rc) 2914 return rc; 2915 2916 isec->sid = newsid; 2917 return 0; 2918} 2919 2920static int selinux_inode_listsecurity(struct inode *inode, char *buffer, size_t buffer_size) 2921{ 2922 const int len = sizeof(XATTR_NAME_SELINUX); 2923 if (buffer && len <= buffer_size) 2924 memcpy(buffer, XATTR_NAME_SELINUX, len); 2925 return len; 2926} 2927 2928static void selinux_inode_getsecid(const struct inode *inode, u32 *secid) 2929{ 2930 struct inode_security_struct *isec = inode->i_security; 2931 *secid = isec->sid; 2932} 2933 2934/* file security operations */ 2935 2936static int selinux_revalidate_file_permission(struct file *file, int mask) 2937{ 2938 const struct cred *cred = current_cred(); 2939 struct inode *inode = file->f_path.dentry->d_inode; 2940 2941 /* file_mask_to_av won't add FILE__WRITE if MAY_APPEND is set */ 2942 if ((file->f_flags & O_APPEND) && (mask & MAY_WRITE)) 2943 mask |= MAY_APPEND; 2944 2945 return file_has_perm(cred, file, 2946 file_mask_to_av(inode->i_mode, mask)); 2947} 2948 2949static int selinux_file_permission(struct file *file, int mask) 2950{ 2951 struct inode *inode = file->f_path.dentry->d_inode; 2952 struct file_security_struct *fsec = file->f_security; 2953 struct inode_security_struct *isec = inode->i_security; 2954 u32 sid = current_sid(); 2955 2956 if (!mask) 2957 /* No permission to check. Existence test. */ 2958 return 0; 2959 2960 if (sid == fsec->sid && fsec->isid == isec->sid && 2961 fsec->pseqno == avc_policy_seqno()) 2962 /* No change since dentry_open check. */ 2963 return 0; 2964 2965 return selinux_revalidate_file_permission(file, mask); 2966} 2967 2968static int selinux_file_alloc_security(struct file *file) 2969{ 2970 return file_alloc_security(file); 2971} 2972 2973static void selinux_file_free_security(struct file *file) 2974{ 2975 file_free_security(file); 2976} 2977 2978static int selinux_file_ioctl(struct file *file, unsigned int cmd, 2979 unsigned long arg) 2980{ 2981 const struct cred *cred = current_cred(); 2982 u32 av = 0; 2983 2984 if (_IOC_DIR(cmd) & _IOC_WRITE) 2985 av |= FILE__WRITE; 2986 if (_IOC_DIR(cmd) & _IOC_READ) 2987 av |= FILE__READ; 2988 if (!av) 2989 av = FILE__IOCTL; 2990 2991 return file_has_perm(cred, file, av); 2992} 2993 2994static int file_map_prot_check(struct file *file, unsigned long prot, int shared) 2995{ 2996 const struct cred *cred = current_cred(); 2997 int rc = 0; 2998 2999#ifndef CONFIG_PPC32 3000 if ((prot & PROT_EXEC) && (!file || (!shared && (prot & PROT_WRITE)))) { 3001 /* 3002 * We are making executable an anonymous mapping or a 3003 * private file mapping that will also be writable. 3004 * This has an additional check. 3005 */ 3006 rc = cred_has_perm(cred, cred, PROCESS__EXECMEM); 3007 if (rc) 3008 goto error; 3009 } 3010#endif 3011 3012 if (file) { 3013 /* read access is always possible with a mapping */ 3014 u32 av = FILE__READ; 3015 3016 /* write access only matters if the mapping is shared */ 3017 if (shared && (prot & PROT_WRITE)) 3018 av |= FILE__WRITE; 3019 3020 if (prot & PROT_EXEC) 3021 av |= FILE__EXECUTE; 3022 3023 return file_has_perm(cred, file, av); 3024 } 3025 3026error: 3027 return rc; 3028} 3029 3030static int selinux_file_mmap(struct file *file, unsigned long reqprot, 3031 unsigned long prot, unsigned long flags, 3032 unsigned long addr, unsigned long addr_only) 3033{ 3034 int rc = 0; 3035 u32 sid = current_sid(); 3036 3037 if (addr < mmap_min_addr) 3038 rc = avc_has_perm(sid, sid, SECCLASS_MEMPROTECT, 3039 MEMPROTECT__MMAP_ZERO, NULL); 3040 if (rc || addr_only) 3041 return rc; 3042 3043 if (selinux_checkreqprot) 3044 prot = reqprot; 3045 3046 return file_map_prot_check(file, prot, 3047 (flags & MAP_TYPE) == MAP_SHARED); 3048} 3049 3050static int selinux_file_mprotect(struct vm_area_struct *vma, 3051 unsigned long reqprot, 3052 unsigned long prot) 3053{ 3054 const struct cred *cred = current_cred(); 3055 3056 if (selinux_checkreqprot) 3057 prot = reqprot; 3058 3059#ifndef CONFIG_PPC32 3060 if ((prot & PROT_EXEC) && !(vma->vm_flags & VM_EXEC)) { 3061 int rc = 0; 3062 if (vma->vm_start >= vma->vm_mm->start_brk && 3063 vma->vm_end <= vma->vm_mm->brk) { 3064 rc = cred_has_perm(cred, cred, PROCESS__EXECHEAP); 3065 } else if (!vma->vm_file && 3066 vma->vm_start <= vma->vm_mm->start_stack && 3067 vma->vm_end >= vma->vm_mm->start_stack) { 3068 rc = current_has_perm(current, PROCESS__EXECSTACK); 3069 } else if (vma->vm_file && vma->anon_vma) { 3070 /* 3071 * We are making executable a file mapping that has 3072 * had some COW done. Since pages might have been 3073 * written, check ability to execute the possibly 3074 * modified content. This typically should only 3075 * occur for text relocations. 3076 */ 3077 rc = file_has_perm(cred, vma->vm_file, FILE__EXECMOD); 3078 } 3079 if (rc) 3080 return rc; 3081 } 3082#endif 3083 3084 return file_map_prot_check(vma->vm_file, prot, vma->vm_flags&VM_SHARED); 3085} 3086 3087static int selinux_file_lock(struct file *file, unsigned int cmd) 3088{ 3089 const struct cred *cred = current_cred(); 3090 3091 return file_has_perm(cred, file, FILE__LOCK); 3092} 3093 3094static int selinux_file_fcntl(struct file *file, unsigned int cmd, 3095 unsigned long arg) 3096{ 3097 const struct cred *cred = current_cred(); 3098 int err = 0; 3099 3100 switch (cmd) { 3101 case F_SETFL: 3102 if (!file->f_path.dentry || !file->f_path.dentry->d_inode) { 3103 err = -EINVAL; 3104 break; 3105 } 3106 3107 if ((file->f_flags & O_APPEND) && !(arg & O_APPEND)) { 3108 err = file_has_perm(cred, file, FILE__WRITE); 3109 break; 3110 } 3111 /* fall through */ 3112 case F_SETOWN: 3113 case F_SETSIG: 3114 case F_GETFL: 3115 case F_GETOWN: 3116 case F_GETSIG: 3117 /* Just check FD__USE permission */ 3118 err = file_has_perm(cred, file, 0); 3119 break; 3120 case F_GETLK: 3121 case F_SETLK: 3122 case F_SETLKW: 3123#if BITS_PER_LONG == 32 3124 case F_GETLK64: 3125 case F_SETLK64: 3126 case F_SETLKW64: 3127#endif 3128 if (!file->f_path.dentry || !file->f_path.dentry->d_inode) { 3129 err = -EINVAL; 3130 break; 3131 } 3132 err = file_has_perm(cred, file, FILE__LOCK); 3133 break; 3134 } 3135 3136 return err; 3137} 3138 3139static int selinux_file_set_fowner(struct file *file) 3140{ 3141 struct file_security_struct *fsec; 3142 3143 fsec = file->f_security; 3144 fsec->fown_sid = current_sid(); 3145 3146 return 0; 3147} 3148 3149static int selinux_file_send_sigiotask(struct task_struct *tsk, 3150 struct fown_struct *fown, int signum) 3151{ 3152 struct file *file; 3153 u32 sid = task_sid(tsk); 3154 u32 perm; 3155 struct file_security_struct *fsec; 3156 3157 /* struct fown_struct is never outside the context of a struct file */ 3158 file = container_of(fown, struct file, f_owner); 3159 3160 fsec = file->f_security; 3161 3162 if (!signum) 3163 perm = signal_to_av(SIGIO); /* as per send_sigio_to_task */ 3164 else 3165 perm = signal_to_av(signum); 3166 3167 return avc_has_perm(fsec->fown_sid, sid, 3168 SECCLASS_PROCESS, perm, NULL); 3169} 3170 3171static int selinux_file_receive(struct file *file) 3172{ 3173 const struct cred *cred = current_cred(); 3174 3175 return file_has_perm(cred, file, file_to_av(file)); 3176} 3177 3178static int selinux_dentry_open(struct file *file, const struct cred *cred) 3179{ 3180 struct file_security_struct *fsec; 3181 struct inode *inode; 3182 struct inode_security_struct *isec; 3183 3184 inode = file->f_path.dentry->d_inode; 3185 fsec = file->f_security; 3186 isec = inode->i_security; 3187 /* 3188 * Save inode label and policy sequence number 3189 * at open-time so that selinux_file_permission 3190 * can determine whether revalidation is necessary. 3191 * Task label is already saved in the file security 3192 * struct as its SID. 3193 */ 3194 fsec->isid = isec->sid; 3195 fsec->pseqno = avc_policy_seqno(); 3196 /* 3197 * Since the inode label or policy seqno may have changed 3198 * between the selinux_inode_permission check and the saving 3199 * of state above, recheck that access is still permitted. 3200 * Otherwise, access might never be revalidated against the 3201 * new inode label or new policy. 3202 * This check is not redundant - do not remove. 3203 */ 3204 return inode_has_perm(cred, inode, open_file_to_av(file), NULL); 3205} 3206 3207/* task security operations */ 3208 3209static int selinux_task_create(unsigned long clone_flags) 3210{ 3211 return current_has_perm(current, PROCESS__FORK); 3212} 3213 3214/* 3215 * detach and free the LSM part of a set of credentials 3216 */ 3217static void selinux_cred_free(struct cred *cred) 3218{ 3219 struct task_security_struct *tsec = cred->security; 3220 cred->security = NULL; 3221 kfree(tsec); 3222} 3223 3224/* 3225 * prepare a new set of credentials for modification 3226 */ 3227static int selinux_cred_prepare(struct cred *new, const struct cred *old, 3228 gfp_t gfp) 3229{ 3230 const struct task_security_struct *old_tsec; 3231 struct task_security_struct *tsec; 3232 3233 old_tsec = old->security; 3234 3235 tsec = kmemdup(old_tsec, sizeof(struct task_security_struct), gfp); 3236 if (!tsec) 3237 return -ENOMEM; 3238 3239 new->security = tsec; 3240 return 0; 3241} 3242 3243/* 3244 * set the security data for a kernel service 3245 * - all the creation contexts are set to unlabelled 3246 */ 3247static int selinux_kernel_act_as(struct cred *new, u32 secid) 3248{ 3249 struct task_security_struct *tsec = new->security; 3250 u32 sid = current_sid(); 3251 int ret; 3252 3253 ret = avc_has_perm(sid, secid, 3254 SECCLASS_KERNEL_SERVICE, 3255 KERNEL_SERVICE__USE_AS_OVERRIDE, 3256 NULL); 3257 if (ret == 0) { 3258 tsec->sid = secid; 3259 tsec->create_sid = 0; 3260 tsec->keycreate_sid = 0; 3261 tsec->sockcreate_sid = 0; 3262 } 3263 return ret; 3264} 3265 3266/* 3267 * set the file creation context in a security record to the same as the 3268 * objective context of the specified inode 3269 */ 3270static int selinux_kernel_create_files_as(struct cred *new, struct inode *inode) 3271{ 3272 struct inode_security_struct *isec = inode->i_security; 3273 struct task_security_struct *tsec = new->security; 3274 u32 sid = current_sid(); 3275 int ret; 3276 3277 ret = avc_has_perm(sid, isec->sid, 3278 SECCLASS_KERNEL_SERVICE, 3279 KERNEL_SERVICE__CREATE_FILES_AS, 3280 NULL); 3281 3282 if (ret == 0) 3283 tsec->create_sid = isec->sid; 3284 return 0; 3285} 3286 3287static int selinux_task_setpgid(struct task_struct *p, pid_t pgid) 3288{ 3289 return current_has_perm(p, PROCESS__SETPGID); 3290} 3291 3292static int selinux_task_getpgid(struct task_struct *p) 3293{ 3294 return current_has_perm(p, PROCESS__GETPGID); 3295} 3296 3297static int selinux_task_getsid(struct task_struct *p) 3298{ 3299 return current_has_perm(p, PROCESS__GETSESSION); 3300} 3301 3302static void selinux_task_getsecid(struct task_struct *p, u32 *secid) 3303{ 3304 *secid = task_sid(p); 3305} 3306 3307static int selinux_task_setnice(struct task_struct *p, int nice) 3308{ 3309 int rc; 3310 3311 rc = cap_task_setnice(p, nice); 3312 if (rc) 3313 return rc; 3314 3315 return current_has_perm(p, PROCESS__SETSCHED); 3316} 3317 3318static int selinux_task_setioprio(struct task_struct *p, int ioprio) 3319{ 3320 int rc; 3321 3322 rc = cap_task_setioprio(p, ioprio); 3323 if (rc) 3324 return rc; 3325 3326 return current_has_perm(p, PROCESS__SETSCHED); 3327} 3328 3329static int selinux_task_getioprio(struct task_struct *p) 3330{ 3331 return current_has_perm(p, PROCESS__GETSCHED); 3332} 3333 3334static int selinux_task_setrlimit(unsigned int resource, struct rlimit *new_rlim) 3335{ 3336 struct rlimit *old_rlim = current->signal->rlim + resource; 3337 3338 /* Control the ability to change the hard limit (whether 3339 lowering or raising it), so that the hard limit can 3340 later be used as a safe reset point for the soft limit 3341 upon context transitions. See selinux_bprm_committing_creds. */ 3342 if (old_rlim->rlim_max != new_rlim->rlim_max) 3343 return current_has_perm(current, PROCESS__SETRLIMIT); 3344 3345 return 0; 3346} 3347 3348static int selinux_task_setscheduler(struct task_struct *p, int policy, struct sched_param *lp) 3349{ 3350 int rc; 3351 3352 rc = cap_task_setscheduler(p, policy, lp); 3353 if (rc) 3354 return rc; 3355 3356 return current_has_perm(p, PROCESS__SETSCHED); 3357} 3358 3359static int selinux_task_getscheduler(struct task_struct *p) 3360{ 3361 return current_has_perm(p, PROCESS__GETSCHED); 3362} 3363 3364static int selinux_task_movememory(struct task_struct *p) 3365{ 3366 return current_has_perm(p, PROCESS__SETSCHED); 3367} 3368 3369static int selinux_task_kill(struct task_struct *p, struct siginfo *info, 3370 int sig, u32 secid) 3371{ 3372 u32 perm; 3373 int rc; 3374 3375 if (!sig) 3376 perm = PROCESS__SIGNULL; /* null signal; existence test */ 3377 else 3378 perm = signal_to_av(sig); 3379 if (secid) 3380 rc = avc_has_perm(secid, task_sid(p), 3381 SECCLASS_PROCESS, perm, NULL); 3382 else 3383 rc = current_has_perm(p, perm); 3384 return rc; 3385} 3386 3387static int selinux_task_wait(struct task_struct *p) 3388{ 3389 return task_has_perm(p, current, PROCESS__SIGCHLD); 3390} 3391 3392static void selinux_task_to_inode(struct task_struct *p, 3393 struct inode *inode) 3394{ 3395 struct inode_security_struct *isec = inode->i_security; 3396 u32 sid = task_sid(p); 3397 3398 isec->sid = sid; 3399 isec->initialized = 1; 3400} 3401 3402/* Returns error only if unable to parse addresses */ 3403static int selinux_parse_skb_ipv4(struct sk_buff *skb, 3404 struct avc_audit_data *ad, u8 *proto) 3405{ 3406 int offset, ihlen, ret = -EINVAL; 3407 struct iphdr _iph, *ih; 3408 3409 offset = skb_network_offset(skb); 3410 ih = skb_header_pointer(skb, offset, sizeof(_iph), &_iph); 3411 if (ih == NULL) 3412 goto out; 3413 3414 ihlen = ih->ihl * 4; 3415 if (ihlen < sizeof(_iph)) 3416 goto out; 3417 3418 ad->u.net.v4info.saddr = ih->saddr; 3419 ad->u.net.v4info.daddr = ih->daddr; 3420 ret = 0; 3421 3422 if (proto) 3423 *proto = ih->protocol; 3424 3425 switch (ih->protocol) { 3426 case IPPROTO_TCP: { 3427 struct tcphdr _tcph, *th; 3428 3429 if (ntohs(ih->frag_off) & IP_OFFSET) 3430 break; 3431 3432 offset += ihlen; 3433 th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph); 3434 if (th == NULL) 3435 break; 3436 3437 ad->u.net.sport = th->source; 3438 ad->u.net.dport = th->dest; 3439 break; 3440 } 3441 3442 case IPPROTO_UDP: { 3443 struct udphdr _udph, *uh; 3444 3445 if (ntohs(ih->frag_off) & IP_OFFSET) 3446 break; 3447 3448 offset += ihlen; 3449 uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph); 3450 if (uh == NULL) 3451 break; 3452 3453 ad->u.net.sport = uh->source; 3454 ad->u.net.dport = uh->dest; 3455 break; 3456 } 3457 3458 case IPPROTO_DCCP: { 3459 struct dccp_hdr _dccph, *dh; 3460 3461 if (ntohs(ih->frag_off) & IP_OFFSET) 3462 break; 3463 3464 offset += ihlen; 3465 dh = skb_header_pointer(skb, offset, sizeof(_dccph), &_dccph); 3466 if (dh == NULL) 3467 break; 3468 3469 ad->u.net.sport = dh->dccph_sport; 3470 ad->u.net.dport = dh->dccph_dport; 3471 break; 3472 } 3473 3474 default: 3475 break; 3476 } 3477out: 3478 return ret; 3479} 3480 3481#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE) 3482 3483/* Returns error only if unable to parse addresses */ 3484static int selinux_parse_skb_ipv6(struct sk_buff *skb, 3485 struct avc_audit_data *ad, u8 *proto) 3486{ 3487 u8 nexthdr; 3488 int ret = -EINVAL, offset; 3489 struct ipv6hdr _ipv6h, *ip6; 3490 3491 offset = skb_network_offset(skb); 3492 ip6 = skb_header_pointer(skb, offset, sizeof(_ipv6h), &_ipv6h); 3493 if (ip6 == NULL) 3494 goto out; 3495 3496 ipv6_addr_copy(&ad->u.net.v6info.saddr, &ip6->saddr); 3497 ipv6_addr_copy(&ad->u.net.v6info.daddr, &ip6->daddr); 3498 ret = 0; 3499 3500 nexthdr = ip6->nexthdr; 3501 offset += sizeof(_ipv6h); 3502 offset = ipv6_skip_exthdr(skb, offset, &nexthdr); 3503 if (offset < 0) 3504 goto out; 3505 3506 if (proto) 3507 *proto = nexthdr; 3508 3509 switch (nexthdr) { 3510 case IPPROTO_TCP: { 3511 struct tcphdr _tcph, *th; 3512 3513 th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph); 3514 if (th == NULL) 3515 break; 3516 3517 ad->u.net.sport = th->source; 3518 ad->u.net.dport = th->dest; 3519 break; 3520 } 3521 3522 case IPPROTO_UDP: { 3523 struct udphdr _udph, *uh; 3524 3525 uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph); 3526 if (uh == NULL) 3527 break; 3528 3529 ad->u.net.sport = uh->source; 3530 ad->u.net.dport = uh->dest; 3531 break; 3532 } 3533 3534 case IPPROTO_DCCP: { 3535 struct dccp_hdr _dccph, *dh; 3536 3537 dh = skb_header_pointer(skb, offset, sizeof(_dccph), &_dccph); 3538 if (dh == NULL) 3539 break; 3540 3541 ad->u.net.sport = dh->dccph_sport; 3542 ad->u.net.dport = dh->dccph_dport; 3543 break; 3544 } 3545 3546 /* includes fragments */ 3547 default: 3548 break; 3549 } 3550out: 3551 return ret; 3552} 3553 3554#endif /* IPV6 */ 3555 3556static int selinux_parse_skb(struct sk_buff *skb, struct avc_audit_data *ad, 3557 char **_addrp, int src, u8 *proto) 3558{ 3559 char *addrp; 3560 int ret; 3561 3562 switch (ad->u.net.family) { 3563 case PF_INET: 3564 ret = selinux_parse_skb_ipv4(skb, ad, proto); 3565 if (ret) 3566 goto parse_error; 3567 addrp = (char *)(src ? &ad->u.net.v4info.saddr : 3568 &ad->u.net.v4info.daddr); 3569 goto okay; 3570 3571#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE) 3572 case PF_INET6: 3573 ret = selinux_parse_skb_ipv6(skb, ad, proto); 3574 if (ret) 3575 goto parse_error; 3576 addrp = (char *)(src ? &ad->u.net.v6info.saddr : 3577 &ad->u.net.v6info.daddr); 3578 goto okay; 3579#endif /* IPV6 */ 3580 default: 3581 addrp = NULL; 3582 goto okay; 3583 } 3584 3585parse_error: 3586 printk(KERN_WARNING 3587 "SELinux: failure in selinux_parse_skb()," 3588 " unable to parse packet\n"); 3589 return ret; 3590 3591okay: 3592 if (_addrp) 3593 *_addrp = addrp; 3594 return 0; 3595} 3596 3597/** 3598 * selinux_skb_peerlbl_sid - Determine the peer label of a packet 3599 * @skb: the packet 3600 * @family: protocol family 3601 * @sid: the packet's peer label SID 3602 * 3603 * Description: 3604 * Check the various different forms of network peer labeling and determine 3605 * the peer label/SID for the packet; most of the magic actually occurs in 3606 * the security server function security_net_peersid_cmp(). The function 3607 * returns zero if the value in @sid is valid (although it may be SECSID_NULL) 3608 * or -EACCES if @sid is invalid due to inconsistencies with the different 3609 * peer labels. 3610 * 3611 */ 3612static int selinux_skb_peerlbl_sid(struct sk_buff *skb, u16 family, u32 *sid) 3613{ 3614 int err; 3615 u32 xfrm_sid; 3616 u32 nlbl_sid; 3617 u32 nlbl_type; 3618 3619 selinux_skb_xfrm_sid(skb, &xfrm_sid); 3620 selinux_netlbl_skbuff_getsid(skb, family, &nlbl_type, &nlbl_sid); 3621 3622 err = security_net_peersid_resolve(nlbl_sid, nlbl_type, xfrm_sid, sid); 3623 if (unlikely(err)) { 3624 printk(KERN_WARNING 3625 "SELinux: failure in selinux_skb_peerlbl_sid()," 3626 " unable to determine packet's peer label\n"); 3627 return -EACCES; 3628 } 3629 3630 return 0; 3631} 3632 3633/* socket security operations */ 3634static int socket_has_perm(struct task_struct *task, struct socket *sock, 3635 u32 perms) 3636{ 3637 struct inode_security_struct *isec; 3638 struct avc_audit_data ad; 3639 u32 sid; 3640 int err = 0; 3641 3642 isec = SOCK_INODE(sock)->i_security; 3643 3644 if (isec->sid == SECINITSID_KERNEL) 3645 goto out; 3646 sid = task_sid(task); 3647 3648 AVC_AUDIT_DATA_INIT(&ad, NET); 3649 ad.u.net.sk = sock->sk; 3650 err = avc_has_perm(sid, isec->sid, isec->sclass, perms, &ad); 3651 3652out: 3653 return err; 3654} 3655 3656static int selinux_socket_create(int family, int type, 3657 int protocol, int kern) 3658{ 3659 const struct cred *cred = current_cred(); 3660 const struct task_security_struct *tsec = cred->security; 3661 u32 sid, newsid; 3662 u16 secclass; 3663 int err = 0; 3664 3665 if (kern) 3666 goto out; 3667 3668 sid = tsec->sid; 3669 newsid = tsec->sockcreate_sid ?: sid; 3670 3671 secclass = socket_type_to_security_class(family, type, protocol); 3672 err = avc_has_perm(sid, newsid, secclass, SOCKET__CREATE, NULL); 3673 3674out: 3675 return err; 3676} 3677 3678static int selinux_socket_post_create(struct socket *sock, int family, 3679 int type, int protocol, int kern) 3680{ 3681 const struct cred *cred = current_cred(); 3682 const struct task_security_struct *tsec = cred->security; 3683 struct inode_security_struct *isec; 3684 struct sk_security_struct *sksec; 3685 u32 sid, newsid; 3686 int err = 0; 3687 3688 sid = tsec->sid; 3689 newsid = tsec->sockcreate_sid; 3690 3691 isec = SOCK_INODE(sock)->i_security; 3692 3693 if (kern) 3694 isec->sid = SECINITSID_KERNEL; 3695 else if (newsid) 3696 isec->sid = newsid; 3697 else 3698 isec->sid = sid; 3699 3700 isec->sclass = socket_type_to_security_class(family, type, protocol); 3701 isec->initialized = 1; 3702 3703 if (sock->sk) { 3704 sksec = sock->sk->sk_security; 3705 sksec->sid = isec->sid; 3706 sksec->sclass = isec->sclass; 3707 err = selinux_netlbl_socket_post_create(sock->sk, family); 3708 } 3709 3710 return err; 3711} 3712 3713/* Range of port numbers used to automatically bind. 3714 Need to determine whether we should perform a name_bind 3715 permission check between the socket and the port number. */ 3716 3717static int selinux_socket_bind(struct socket *sock, struct sockaddr *address, int addrlen) 3718{ 3719 u16 family; 3720 int err; 3721 3722 err = socket_has_perm(current, sock, SOCKET__BIND); 3723 if (err) 3724 goto out; 3725 3726 /* 3727 * If PF_INET or PF_INET6, check name_bind permission for the port. 3728 * Multiple address binding for SCTP is not supported yet: we just 3729 * check the first address now. 3730 */ 3731 family = sock->sk->sk_family; 3732 if (family == PF_INET || family == PF_INET6) { 3733 char *addrp; 3734 struct inode_security_struct *isec; 3735 struct avc_audit_data ad; 3736 struct sockaddr_in *addr4 = NULL; 3737 struct sockaddr_in6 *addr6 = NULL; 3738 unsigned short snum; 3739 struct sock *sk = sock->sk; 3740 u32 sid, node_perm; 3741 3742 isec = SOCK_INODE(sock)->i_security; 3743 3744 if (family == PF_INET) { 3745 addr4 = (struct sockaddr_in *)address; 3746 snum = ntohs(addr4->sin_port); 3747 addrp = (char *)&addr4->sin_addr.s_addr; 3748 } else { 3749 addr6 = (struct sockaddr_in6 *)address; 3750 snum = ntohs(addr6->sin6_port); 3751 addrp = (char *)&addr6->sin6_addr.s6_addr; 3752 } 3753 3754 if (snum) { 3755 int low, high; 3756 3757 inet_get_local_port_range(&low, &high); 3758 3759 if (snum < max(PROT_SOCK, low) || snum > high) { 3760 err = sel_netport_sid(sk->sk_protocol, 3761 snum, &sid); 3762 if (err) 3763 goto out; 3764 AVC_AUDIT_DATA_INIT(&ad, NET); 3765 ad.u.net.sport = htons(snum); 3766 ad.u.net.family = family; 3767 err = avc_has_perm(isec->sid, sid, 3768 isec->sclass, 3769 SOCKET__NAME_BIND, &ad); 3770 if (err) 3771 goto out; 3772 } 3773 } 3774 3775 switch (isec->sclass) { 3776 case SECCLASS_TCP_SOCKET: 3777 node_perm = TCP_SOCKET__NODE_BIND; 3778 break; 3779 3780 case SECCLASS_UDP_SOCKET: 3781 node_perm = UDP_SOCKET__NODE_BIND; 3782 break; 3783 3784 case SECCLASS_DCCP_SOCKET: 3785 node_perm = DCCP_SOCKET__NODE_BIND; 3786 break; 3787 3788 default: 3789 node_perm = RAWIP_SOCKET__NODE_BIND; 3790 break; 3791 } 3792 3793 err = sel_netnode_sid(addrp, family, &sid); 3794 if (err) 3795 goto out; 3796 3797 AVC_AUDIT_DATA_INIT(&ad, NET); 3798 ad.u.net.sport = htons(snum); 3799 ad.u.net.family = family; 3800 3801 if (family == PF_INET) 3802 ad.u.net.v4info.saddr = addr4->sin_addr.s_addr; 3803 else 3804 ipv6_addr_copy(&ad.u.net.v6info.saddr, &addr6->sin6_addr); 3805 3806 err = avc_has_perm(isec->sid, sid, 3807 isec->sclass, node_perm, &ad); 3808 if (err) 3809 goto out; 3810 } 3811out: 3812 return err; 3813} 3814 3815static int selinux_socket_connect(struct socket *sock, struct sockaddr *address, int addrlen) 3816{ 3817 struct sock *sk = sock->sk; 3818 struct inode_security_struct *isec; 3819 int err; 3820 3821 err = socket_has_perm(current, sock, SOCKET__CONNECT); 3822 if (err) 3823 return err; 3824 3825 /* 3826 * If a TCP or DCCP socket, check name_connect permission for the port. 3827 */ 3828 isec = SOCK_INODE(sock)->i_security; 3829 if (isec->sclass == SECCLASS_TCP_SOCKET || 3830 isec->sclass == SECCLASS_DCCP_SOCKET) { 3831 struct avc_audit_data ad; 3832 struct sockaddr_in *addr4 = NULL; 3833 struct sockaddr_in6 *addr6 = NULL; 3834 unsigned short snum; 3835 u32 sid, perm; 3836 3837 if (sk->sk_family == PF_INET) { 3838 addr4 = (struct sockaddr_in *)address; 3839 if (addrlen < sizeof(struct sockaddr_in)) 3840 return -EINVAL; 3841 snum = ntohs(addr4->sin_port); 3842 } else { 3843 addr6 = (struct sockaddr_in6 *)address; 3844 if (addrlen < SIN6_LEN_RFC2133) 3845 return -EINVAL; 3846 snum = ntohs(addr6->sin6_port); 3847 } 3848 3849 err = sel_netport_sid(sk->sk_protocol, snum, &sid); 3850 if (err) 3851 goto out; 3852 3853 perm = (isec->sclass == SECCLASS_TCP_SOCKET) ? 3854 TCP_SOCKET__NAME_CONNECT : DCCP_SOCKET__NAME_CONNECT; 3855 3856 AVC_AUDIT_DATA_INIT(&ad, NET); 3857 ad.u.net.dport = htons(snum); 3858 ad.u.net.family = sk->sk_family; 3859 err = avc_has_perm(isec->sid, sid, isec->sclass, perm, &ad); 3860 if (err) 3861 goto out; 3862 } 3863 3864 err = selinux_netlbl_socket_connect(sk, address); 3865 3866out: 3867 return err; 3868} 3869 3870static int selinux_socket_listen(struct socket *sock, int backlog) 3871{ 3872 return socket_has_perm(current, sock, SOCKET__LISTEN); 3873} 3874 3875static int selinux_socket_accept(struct socket *sock, struct socket *newsock) 3876{ 3877 int err; 3878 struct inode_security_struct *isec; 3879 struct inode_security_struct *newisec; 3880 3881 err = socket_has_perm(current, sock, SOCKET__ACCEPT); 3882 if (err) 3883 return err; 3884 3885 newisec = SOCK_INODE(newsock)->i_security; 3886 3887 isec = SOCK_INODE(sock)->i_security; 3888 newisec->sclass = isec->sclass; 3889 newisec->sid = isec->sid; 3890 newisec->initialized = 1; 3891 3892 return 0; 3893} 3894 3895static int selinux_socket_sendmsg(struct socket *sock, struct msghdr *msg, 3896 int size) 3897{ 3898 return socket_has_perm(current, sock, SOCKET__WRITE); 3899} 3900 3901static int selinux_socket_recvmsg(struct socket *sock, struct msghdr *msg, 3902 int size, int flags) 3903{ 3904 return socket_has_perm(current, sock, SOCKET__READ); 3905} 3906 3907static int selinux_socket_getsockname(struct socket *sock) 3908{ 3909 return socket_has_perm(current, sock, SOCKET__GETATTR); 3910} 3911 3912static int selinux_socket_getpeername(struct socket *sock) 3913{ 3914 return socket_has_perm(current, sock, SOCKET__GETATTR); 3915} 3916 3917static int selinux_socket_setsockopt(struct socket *sock, int level, int optname) 3918{ 3919 int err; 3920 3921 err = socket_has_perm(current, sock, SOCKET__SETOPT); 3922 if (err) 3923 return err; 3924 3925 return selinux_netlbl_socket_setsockopt(sock, level, optname); 3926} 3927 3928static int selinux_socket_getsockopt(struct socket *sock, int level, 3929 int optname) 3930{ 3931 return socket_has_perm(current, sock, SOCKET__GETOPT); 3932} 3933 3934static int selinux_socket_shutdown(struct socket *sock, int how) 3935{ 3936 return socket_has_perm(current, sock, SOCKET__SHUTDOWN); 3937} 3938 3939static int selinux_socket_unix_stream_connect(struct socket *sock, 3940 struct socket *other, 3941 struct sock *newsk) 3942{ 3943 struct sk_security_struct *ssec; 3944 struct inode_security_struct *isec; 3945 struct inode_security_struct *other_isec; 3946 struct avc_audit_data ad; 3947 int err; 3948 3949 isec = SOCK_INODE(sock)->i_security; 3950 other_isec = SOCK_INODE(other)->i_security; 3951 3952 AVC_AUDIT_DATA_INIT(&ad, NET); 3953 ad.u.net.sk = other->sk; 3954 3955 err = avc_has_perm(isec->sid, other_isec->sid, 3956 isec->sclass, 3957 UNIX_STREAM_SOCKET__CONNECTTO, &ad); 3958 if (err) 3959 return err; 3960 3961 /* connecting socket */ 3962 ssec = sock->sk->sk_security; 3963 ssec->peer_sid = other_isec->sid; 3964 3965 /* server child socket */ 3966 ssec = newsk->sk_security; 3967 ssec->peer_sid = isec->sid; 3968 err = security_sid_mls_copy(other_isec->sid, ssec->peer_sid, &ssec->sid); 3969 3970 return err; 3971} 3972 3973static int selinux_socket_unix_may_send(struct socket *sock, 3974 struct socket *other) 3975{ 3976 struct inode_security_struct *isec; 3977 struct inode_security_struct *other_isec; 3978 struct avc_audit_data ad; 3979 int err; 3980 3981 isec = SOCK_INODE(sock)->i_security; 3982 other_isec = SOCK_INODE(other)->i_security; 3983 3984 AVC_AUDIT_DATA_INIT(&ad, NET); 3985 ad.u.net.sk = other->sk; 3986 3987 err = avc_has_perm(isec->sid, other_isec->sid, 3988 isec->sclass, SOCKET__SENDTO, &ad); 3989 if (err) 3990 return err; 3991 3992 return 0; 3993} 3994 3995static int selinux_inet_sys_rcv_skb(int ifindex, char *addrp, u16 family, 3996 u32 peer_sid, 3997 struct avc_audit_data *ad) 3998{ 3999 int err; 4000 u32 if_sid; 4001 u32 node_sid; 4002 4003 err = sel_netif_sid(ifindex, &if_sid); 4004 if (err) 4005 return err; 4006 err = avc_has_perm(peer_sid, if_sid, 4007 SECCLASS_NETIF, NETIF__INGRESS, ad); 4008 if (err) 4009 return err; 4010 4011 err = sel_netnode_sid(addrp, family, &node_sid); 4012 if (err) 4013 return err; 4014 return avc_has_perm(peer_sid, node_sid, 4015 SECCLASS_NODE, NODE__RECVFROM, ad); 4016} 4017 4018static int selinux_sock_rcv_skb_compat(struct sock *sk, struct sk_buff *skb, 4019 u16 family) 4020{ 4021 int err = 0; 4022 struct sk_security_struct *sksec = sk->sk_security; 4023 u32 peer_sid; 4024 u32 sk_sid = sksec->sid; 4025 struct avc_audit_data ad; 4026 char *addrp; 4027 4028 AVC_AUDIT_DATA_INIT(&ad, NET); 4029 ad.u.net.netif = skb->iif; 4030 ad.u.net.family = family; 4031 err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL); 4032 if (err) 4033 return err; 4034 4035 if (selinux_secmark_enabled()) { 4036 err = avc_has_perm(sk_sid, skb->secmark, SECCLASS_PACKET, 4037 PACKET__RECV, &ad); 4038 if (err) 4039 return err; 4040 } 4041 4042 if (selinux_policycap_netpeer) { 4043 err = selinux_skb_peerlbl_sid(skb, family, &peer_sid); 4044 if (err) 4045 return err; 4046 err = avc_has_perm(sk_sid, peer_sid, 4047 SECCLASS_PEER, PEER__RECV, &ad); 4048 if (err) 4049 selinux_netlbl_err(skb, err, 0); 4050 } else { 4051 err = selinux_netlbl_sock_rcv_skb(sksec, skb, family, &ad); 4052 if (err) 4053 return err; 4054 err = selinux_xfrm_sock_rcv_skb(sksec->sid, skb, &ad); 4055 } 4056 4057 return err; 4058} 4059 4060static int selinux_socket_sock_rcv_skb(struct sock *sk, struct sk_buff *skb) 4061{ 4062 int err; 4063 struct sk_security_struct *sksec = sk->sk_security; 4064 u16 family = sk->sk_family; 4065 u32 sk_sid = sksec->sid; 4066 struct avc_audit_data ad; 4067 char *addrp; 4068 u8 secmark_active; 4069 u8 peerlbl_active; 4070 4071 if (family != PF_INET && family != PF_INET6) 4072 return 0; 4073 4074 /* Handle mapped IPv4 packets arriving via IPv6 sockets */ 4075 if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP)) 4076 family = PF_INET; 4077 4078 /* If any sort of compatibility mode is enabled then handoff processing 4079 * to the selinux_sock_rcv_skb_compat() function to deal with the 4080 * special handling. We do this in an attempt to keep this function 4081 * as fast and as clean as possible. */ 4082 if (!selinux_policycap_netpeer) 4083 return selinux_sock_rcv_skb_compat(sk, skb, family); 4084 4085 secmark_active = selinux_secmark_enabled(); 4086 peerlbl_active = netlbl_enabled() || selinux_xfrm_enabled(); 4087 if (!secmark_active && !peerlbl_active) 4088 return 0; 4089 4090 AVC_AUDIT_DATA_INIT(&ad, NET); 4091 ad.u.net.netif = skb->iif; 4092 ad.u.net.family = family; 4093 err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL); 4094 if (err) 4095 return err; 4096 4097 if (peerlbl_active) { 4098 u32 peer_sid; 4099 4100 err = selinux_skb_peerlbl_sid(skb, family, &peer_sid); 4101 if (err) 4102 return err; 4103 err = selinux_inet_sys_rcv_skb(skb->iif, addrp, family, 4104 peer_sid, &ad); 4105 if (err) { 4106 selinux_netlbl_err(skb, err, 0); 4107 return err; 4108 } 4109 err = avc_has_perm(sk_sid, peer_sid, SECCLASS_PEER, 4110 PEER__RECV, &ad); 4111 if (err) 4112 selinux_netlbl_err(skb, err, 0); 4113 } 4114 4115 if (secmark_active) { 4116 err = avc_has_perm(sk_sid, skb->secmark, SECCLASS_PACKET, 4117 PACKET__RECV, &ad); 4118 if (err) 4119 return err; 4120 } 4121 4122 return err; 4123} 4124 4125static int selinux_socket_getpeersec_stream(struct socket *sock, char __user *optval, 4126 int __user *optlen, unsigned len) 4127{ 4128 int err = 0; 4129 char *scontext; 4130 u32 scontext_len; 4131 struct sk_security_struct *ssec; 4132 struct inode_security_struct *isec; 4133 u32 peer_sid = SECSID_NULL; 4134 4135 isec = SOCK_INODE(sock)->i_security; 4136 4137 if (isec->sclass == SECCLASS_UNIX_STREAM_SOCKET || 4138 isec->sclass == SECCLASS_TCP_SOCKET) { 4139 ssec = sock->sk->sk_security; 4140 peer_sid = ssec->peer_sid; 4141 } 4142 if (peer_sid == SECSID_NULL) { 4143 err = -ENOPROTOOPT; 4144 goto out; 4145 } 4146 4147 err = security_sid_to_context(peer_sid, &scontext, &scontext_len); 4148 4149 if (err) 4150 goto out; 4151 4152 if (scontext_len > len) { 4153 err = -ERANGE; 4154 goto out_len; 4155 } 4156 4157 if (copy_to_user(optval, scontext, scontext_len)) 4158 err = -EFAULT; 4159 4160out_len: 4161 if (put_user(scontext_len, optlen)) 4162 err = -EFAULT; 4163 4164 kfree(scontext); 4165out: 4166 return err; 4167} 4168 4169static int selinux_socket_getpeersec_dgram(struct socket *sock, struct sk_buff *skb, u32 *secid) 4170{ 4171 u32 peer_secid = SECSID_NULL; 4172 u16 family; 4173 4174 if (skb && skb->protocol == htons(ETH_P_IP)) 4175 family = PF_INET; 4176 else if (skb && skb->protocol == htons(ETH_P_IPV6)) 4177 family = PF_INET6; 4178 else if (sock) 4179 family = sock->sk->sk_family; 4180 else 4181 goto out; 4182 4183 if (sock && family == PF_UNIX) 4184 selinux_inode_getsecid(SOCK_INODE(sock), &peer_secid); 4185 else if (skb) 4186 selinux_skb_peerlbl_sid(skb, family, &peer_secid); 4187 4188out: 4189 *secid = peer_secid; 4190 if (peer_secid == SECSID_NULL) 4191 return -EINVAL; 4192 return 0; 4193} 4194 4195static int selinux_sk_alloc_security(struct sock *sk, int family, gfp_t priority) 4196{ 4197 return sk_alloc_security(sk, family, priority); 4198} 4199 4200static void selinux_sk_free_security(struct sock *sk) 4201{ 4202 sk_free_security(sk); 4203} 4204 4205static void selinux_sk_clone_security(const struct sock *sk, struct sock *newsk) 4206{ 4207 struct sk_security_struct *ssec = sk->sk_security; 4208 struct sk_security_struct *newssec = newsk->sk_security; 4209 4210 newssec->sid = ssec->sid; 4211 newssec->peer_sid = ssec->peer_sid; 4212 newssec->sclass = ssec->sclass; 4213 4214 selinux_netlbl_sk_security_reset(newssec); 4215} 4216 4217static void selinux_sk_getsecid(struct sock *sk, u32 *secid) 4218{ 4219 if (!sk) 4220 *secid = SECINITSID_ANY_SOCKET; 4221 else { 4222 struct sk_security_struct *sksec = sk->sk_security; 4223 4224 *secid = sksec->sid; 4225 } 4226} 4227 4228static void selinux_sock_graft(struct sock *sk, struct socket *parent) 4229{ 4230 struct inode_security_struct *isec = SOCK_INODE(parent)->i_security; 4231 struct sk_security_struct *sksec = sk->sk_security; 4232 4233 if (sk->sk_family == PF_INET || sk->sk_family == PF_INET6 || 4234 sk->sk_family == PF_UNIX) 4235 isec->sid = sksec->sid; 4236 sksec->sclass = isec->sclass; 4237} 4238 4239static int selinux_inet_conn_request(struct sock *sk, struct sk_buff *skb, 4240 struct request_sock *req) 4241{ 4242 struct sk_security_struct *sksec = sk->sk_security; 4243 int err; 4244 u16 family = sk->sk_family; 4245 u32 newsid; 4246 u32 peersid; 4247 4248 /* handle mapped IPv4 packets arriving via IPv6 sockets */ 4249 if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP)) 4250 family = PF_INET; 4251 4252 err = selinux_skb_peerlbl_sid(skb, family, &peersid); 4253 if (err) 4254 return err; 4255 if (peersid == SECSID_NULL) { 4256 req->secid = sksec->sid; 4257 req->peer_secid = SECSID_NULL; 4258 } else { 4259 err = security_sid_mls_copy(sksec->sid, peersid, &newsid); 4260 if (err) 4261 return err; 4262 req->secid = newsid; 4263 req->peer_secid = peersid; 4264 } 4265 4266 return selinux_netlbl_inet_conn_request(req, family); 4267} 4268 4269static void selinux_inet_csk_clone(struct sock *newsk, 4270 const struct request_sock *req) 4271{ 4272 struct sk_security_struct *newsksec = newsk->sk_security; 4273 4274 newsksec->sid = req->secid; 4275 newsksec->peer_sid = req->peer_secid; 4276 /* NOTE: Ideally, we should also get the isec->sid for the 4277 new socket in sync, but we don't have the isec available yet. 4278 So we will wait until sock_graft to do it, by which 4279 time it will have been created and available. */ 4280 4281 /* We don't need to take any sort of lock here as we are the only 4282 * thread with access to newsksec */ 4283 selinux_netlbl_inet_csk_clone(newsk, req->rsk_ops->family); 4284} 4285 4286static void selinux_inet_conn_established(struct sock *sk, struct sk_buff *skb) 4287{ 4288 u16 family = sk->sk_family; 4289 struct sk_security_struct *sksec = sk->sk_security; 4290 4291 /* handle mapped IPv4 packets arriving via IPv6 sockets */ 4292 if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP)) 4293 family = PF_INET; 4294 4295 selinux_skb_peerlbl_sid(skb, family, &sksec->peer_sid); 4296} 4297 4298static void selinux_req_classify_flow(const struct request_sock *req, 4299 struct flowi *fl) 4300{ 4301 fl->secid = req->secid; 4302} 4303 4304static int selinux_nlmsg_perm(struct sock *sk, struct sk_buff *skb) 4305{ 4306 int err = 0; 4307 u32 perm; 4308 struct nlmsghdr *nlh; 4309 struct socket *sock = sk->sk_socket; 4310 struct inode_security_struct *isec = SOCK_INODE(sock)->i_security; 4311 4312 if (skb->len < NLMSG_SPACE(0)) { 4313 err = -EINVAL; 4314 goto out; 4315 } 4316 nlh = nlmsg_hdr(skb); 4317 4318 err = selinux_nlmsg_lookup(isec->sclass, nlh->nlmsg_type, &perm); 4319 if (err) { 4320 if (err == -EINVAL) { 4321 audit_log(current->audit_context, GFP_KERNEL, AUDIT_SELINUX_ERR, 4322 "SELinux: unrecognized netlink message" 4323 " type=%hu for sclass=%hu\n", 4324 nlh->nlmsg_type, isec->sclass); 4325 if (!selinux_enforcing || security_get_allow_unknown()) 4326 err = 0; 4327 } 4328 4329 /* Ignore */ 4330 if (err == -ENOENT) 4331 err = 0; 4332 goto out; 4333 } 4334 4335 err = socket_has_perm(current, sock, perm); 4336out: 4337 return err; 4338} 4339 4340#ifdef CONFIG_NETFILTER 4341 4342static unsigned int selinux_ip_forward(struct sk_buff *skb, int ifindex, 4343 u16 family) 4344{ 4345 int err; 4346 char *addrp; 4347 u32 peer_sid; 4348 struct avc_audit_data ad; 4349 u8 secmark_active; 4350 u8 netlbl_active; 4351 u8 peerlbl_active; 4352 4353 if (!selinux_policycap_netpeer) 4354 return NF_ACCEPT; 4355 4356 secmark_active = selinux_secmark_enabled(); 4357 netlbl_active = netlbl_enabled(); 4358 peerlbl_active = netlbl_active || selinux_xfrm_enabled(); 4359 if (!secmark_active && !peerlbl_active) 4360 return NF_ACCEPT; 4361 4362 if (selinux_skb_peerlbl_sid(skb, family, &peer_sid) != 0) 4363 return NF_DROP; 4364 4365 AVC_AUDIT_DATA_INIT(&ad, NET); 4366 ad.u.net.netif = ifindex; 4367 ad.u.net.family = family; 4368 if (selinux_parse_skb(skb, &ad, &addrp, 1, NULL) != 0) 4369 return NF_DROP; 4370 4371 if (peerlbl_active) { 4372 err = selinux_inet_sys_rcv_skb(ifindex, addrp, family, 4373 peer_sid, &ad); 4374 if (err) { 4375 selinux_netlbl_err(skb, err, 1); 4376 return NF_DROP; 4377 } 4378 } 4379 4380 if (secmark_active) 4381 if (avc_has_perm(peer_sid, skb->secmark, 4382 SECCLASS_PACKET, PACKET__FORWARD_IN, &ad)) 4383 return NF_DROP; 4384 4385 if (netlbl_active) 4386 /* we do this in the FORWARD path and not the POST_ROUTING 4387 * path because we want to make sure we apply the necessary 4388 * labeling before IPsec is applied so we can leverage AH 4389 * protection */ 4390 if (selinux_netlbl_skbuff_setsid(skb, family, peer_sid) != 0) 4391 return NF_DROP; 4392 4393 return NF_ACCEPT; 4394} 4395 4396static unsigned int selinux_ipv4_forward(unsigned int hooknum, 4397 struct sk_buff *skb, 4398 const struct net_device *in, 4399 const struct net_device *out, 4400 int (*okfn)(struct sk_buff *)) 4401{ 4402 return selinux_ip_forward(skb, in->ifindex, PF_INET); 4403} 4404 4405#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE) 4406static unsigned int selinux_ipv6_forward(unsigned int hooknum, 4407 struct sk_buff *skb, 4408 const struct net_device *in, 4409 const struct net_device *out, 4410 int (*okfn)(struct sk_buff *)) 4411{ 4412 return selinux_ip_forward(skb, in->ifindex, PF_INET6); 4413} 4414#endif /* IPV6 */ 4415 4416static unsigned int selinux_ip_output(struct sk_buff *skb, 4417 u16 family) 4418{ 4419 u32 sid; 4420 4421 if (!netlbl_enabled()) 4422 return NF_ACCEPT; 4423 4424 /* we do this in the LOCAL_OUT path and not the POST_ROUTING path 4425 * because we want to make sure we apply the necessary labeling 4426 * before IPsec is applied so we can leverage AH protection */ 4427 if (skb->sk) { 4428 struct sk_security_struct *sksec = skb->sk->sk_security; 4429 sid = sksec->sid; 4430 } else 4431 sid = SECINITSID_KERNEL; 4432 if (selinux_netlbl_skbuff_setsid(skb, family, sid) != 0) 4433 return NF_DROP; 4434 4435 return NF_ACCEPT; 4436} 4437 4438static unsigned int selinux_ipv4_output(unsigned int hooknum, 4439 struct sk_buff *skb, 4440 const struct net_device *in, 4441 const struct net_device *out, 4442 int (*okfn)(struct sk_buff *)) 4443{ 4444 return selinux_ip_output(skb, PF_INET); 4445} 4446 4447static unsigned int selinux_ip_postroute_compat(struct sk_buff *skb, 4448 int ifindex, 4449 u16 family) 4450{ 4451 struct sock *sk = skb->sk; 4452 struct sk_security_struct *sksec; 4453 struct avc_audit_data ad; 4454 char *addrp; 4455 u8 proto; 4456 4457 if (sk == NULL) 4458 return NF_ACCEPT; 4459 sksec = sk->sk_security; 4460 4461 AVC_AUDIT_DATA_INIT(&ad, NET); 4462 ad.u.net.netif = ifindex; 4463 ad.u.net.family = family; 4464 if (selinux_parse_skb(skb, &ad, &addrp, 0, &proto)) 4465 return NF_DROP; 4466 4467 if (selinux_secmark_enabled()) 4468 if (avc_has_perm(sksec->sid, skb->secmark, 4469 SECCLASS_PACKET, PACKET__SEND, &ad)) 4470 return NF_DROP; 4471 4472 if (selinux_policycap_netpeer) 4473 if (selinux_xfrm_postroute_last(sksec->sid, skb, &ad, proto)) 4474 return NF_DROP; 4475 4476 return NF_ACCEPT; 4477} 4478 4479static unsigned int selinux_ip_postroute(struct sk_buff *skb, int ifindex, 4480 u16 family) 4481{ 4482 u32 secmark_perm; 4483 u32 peer_sid; 4484 struct sock *sk; 4485 struct avc_audit_data ad; 4486 char *addrp; 4487 u8 secmark_active; 4488 u8 peerlbl_active; 4489 4490 /* If any sort of compatibility mode is enabled then handoff processing 4491 * to the selinux_ip_postroute_compat() function to deal with the 4492 * special handling. We do this in an attempt to keep this function 4493 * as fast and as clean as possible. */ 4494 if (!selinux_policycap_netpeer) 4495 return selinux_ip_postroute_compat(skb, ifindex, family); 4496#ifdef CONFIG_XFRM 4497 /* If skb->dst->xfrm is non-NULL then the packet is undergoing an IPsec 4498 * packet transformation so allow the packet to pass without any checks 4499 * since we'll have another chance to perform access control checks 4500 * when the packet is on it's final way out. 4501 * NOTE: there appear to be some IPv6 multicast cases where skb->dst 4502 * is NULL, in this case go ahead and apply access control. */ 4503 if (skb_dst(skb) != NULL && skb_dst(skb)->xfrm != NULL) 4504 return NF_ACCEPT; 4505#endif 4506 secmark_active = selinux_secmark_enabled(); 4507 peerlbl_active = netlbl_enabled() || selinux_xfrm_enabled(); 4508 if (!secmark_active && !peerlbl_active) 4509 return NF_ACCEPT; 4510 4511 /* if the packet is being forwarded then get the peer label from the 4512 * packet itself; otherwise check to see if it is from a local 4513 * application or the kernel, if from an application get the peer label 4514 * from the sending socket, otherwise use the kernel's sid */ 4515 sk = skb->sk; 4516 if (sk == NULL) { 4517 switch (family) { 4518 case PF_INET: 4519 if (IPCB(skb)->flags & IPSKB_FORWARDED) 4520 secmark_perm = PACKET__FORWARD_OUT; 4521 else 4522 secmark_perm = PACKET__SEND; 4523 break; 4524 case PF_INET6: 4525 if (IP6CB(skb)->flags & IP6SKB_FORWARDED) 4526 secmark_perm = PACKET__FORWARD_OUT; 4527 else 4528 secmark_perm = PACKET__SEND; 4529 break; 4530 default: 4531 return NF_DROP; 4532 } 4533 if (secmark_perm == PACKET__FORWARD_OUT) { 4534 if (selinux_skb_peerlbl_sid(skb, family, &peer_sid)) 4535 return NF_DROP; 4536 } else 4537 peer_sid = SECINITSID_KERNEL; 4538 } else { 4539 struct sk_security_struct *sksec = sk->sk_security; 4540 peer_sid = sksec->sid; 4541 secmark_perm = PACKET__SEND; 4542 } 4543 4544 AVC_AUDIT_DATA_INIT(&ad, NET); 4545 ad.u.net.netif = ifindex; 4546 ad.u.net.family = family; 4547 if (selinux_parse_skb(skb, &ad, &addrp, 0, NULL)) 4548 return NF_DROP; 4549 4550 if (secmark_active) 4551 if (avc_has_perm(peer_sid, skb->secmark, 4552 SECCLASS_PACKET, secmark_perm, &ad)) 4553 return NF_DROP; 4554 4555 if (peerlbl_active) { 4556 u32 if_sid; 4557 u32 node_sid; 4558 4559 if (sel_netif_sid(ifindex, &if_sid)) 4560 return NF_DROP; 4561 if (avc_has_perm(peer_sid, if_sid, 4562 SECCLASS_NETIF, NETIF__EGRESS, &ad)) 4563 return NF_DROP; 4564 4565 if (sel_netnode_sid(addrp, family, &node_sid)) 4566 return NF_DROP; 4567 if (avc_has_perm(peer_sid, node_sid, 4568 SECCLASS_NODE, NODE__SENDTO, &ad)) 4569 return NF_DROP; 4570 } 4571 4572 return NF_ACCEPT; 4573} 4574 4575static unsigned int selinux_ipv4_postroute(unsigned int hooknum, 4576 struct sk_buff *skb, 4577 const struct net_device *in, 4578 const struct net_device *out, 4579 int (*okfn)(struct sk_buff *)) 4580{ 4581 return selinux_ip_postroute(skb, out->ifindex, PF_INET); 4582} 4583 4584#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE) 4585static unsigned int selinux_ipv6_postroute(unsigned int hooknum, 4586 struct sk_buff *skb, 4587 const struct net_device *in, 4588 const struct net_device *out, 4589 int (*okfn)(struct sk_buff *)) 4590{ 4591 return selinux_ip_postroute(skb, out->ifindex, PF_INET6); 4592} 4593#endif /* IPV6 */ 4594 4595#endif /* CONFIG_NETFILTER */ 4596 4597static int selinux_netlink_send(struct sock *sk, struct sk_buff *skb) 4598{ 4599 int err; 4600 4601 err = cap_netlink_send(sk, skb); 4602 if (err) 4603 return err; 4604 4605 if (policydb_loaded_version >= POLICYDB_VERSION_NLCLASS) 4606 err = selinux_nlmsg_perm(sk, skb); 4607 4608 return err; 4609} 4610 4611static int selinux_netlink_recv(struct sk_buff *skb, int capability) 4612{ 4613 int err; 4614 struct avc_audit_data ad; 4615 4616 err = cap_netlink_recv(skb, capability); 4617 if (err) 4618 return err; 4619 4620 AVC_AUDIT_DATA_INIT(&ad, CAP); 4621 ad.u.cap = capability; 4622 4623 return avc_has_perm(NETLINK_CB(skb).sid, NETLINK_CB(skb).sid, 4624 SECCLASS_CAPABILITY, CAP_TO_MASK(capability), &ad); 4625} 4626 4627static int ipc_alloc_security(struct task_struct *task, 4628 struct kern_ipc_perm *perm, 4629 u16 sclass) 4630{ 4631 struct ipc_security_struct *isec; 4632 u32 sid; 4633 4634 isec = kzalloc(sizeof(struct ipc_security_struct), GFP_KERNEL); 4635 if (!isec) 4636 return -ENOMEM; 4637 4638 sid = task_sid(task); 4639 isec->sclass = sclass; 4640 isec->sid = sid; 4641 perm->security = isec; 4642 4643 return 0; 4644} 4645 4646static void ipc_free_security(struct kern_ipc_perm *perm) 4647{ 4648 struct ipc_security_struct *isec = perm->security; 4649 perm->security = NULL; 4650 kfree(isec); 4651} 4652 4653static int msg_msg_alloc_security(struct msg_msg *msg) 4654{ 4655 struct msg_security_struct *msec; 4656 4657 msec = kzalloc(sizeof(struct msg_security_struct), GFP_KERNEL); 4658 if (!msec) 4659 return -ENOMEM; 4660 4661 msec->sid = SECINITSID_UNLABELED; 4662 msg->security = msec; 4663 4664 return 0; 4665} 4666 4667static void msg_msg_free_security(struct msg_msg *msg) 4668{ 4669 struct msg_security_struct *msec = msg->security; 4670 4671 msg->security = NULL; 4672 kfree(msec); 4673} 4674 4675static int ipc_has_perm(struct kern_ipc_perm *ipc_perms, 4676 u32 perms) 4677{ 4678 struct ipc_security_struct *isec; 4679 struct avc_audit_data ad; 4680 u32 sid = current_sid(); 4681 4682 isec = ipc_perms->security; 4683 4684 AVC_AUDIT_DATA_INIT(&ad, IPC); 4685 ad.u.ipc_id = ipc_perms->key; 4686 4687 return avc_has_perm(sid, isec->sid, isec->sclass, perms, &ad); 4688} 4689 4690static int selinux_msg_msg_alloc_security(struct msg_msg *msg) 4691{ 4692 return msg_msg_alloc_security(msg); 4693} 4694 4695static void selinux_msg_msg_free_security(struct msg_msg *msg) 4696{ 4697 msg_msg_free_security(msg); 4698} 4699 4700/* message queue security operations */ 4701static int selinux_msg_queue_alloc_security(struct msg_queue *msq) 4702{ 4703 struct ipc_security_struct *isec; 4704 struct avc_audit_data ad; 4705 u32 sid = current_sid(); 4706 int rc; 4707 4708 rc = ipc_alloc_security(current, &msq->q_perm, SECCLASS_MSGQ); 4709 if (rc) 4710 return rc; 4711 4712 isec = msq->q_perm.security; 4713 4714 AVC_AUDIT_DATA_INIT(&ad, IPC); 4715 ad.u.ipc_id = msq->q_perm.key; 4716 4717 rc = avc_has_perm(sid, isec->sid, SECCLASS_MSGQ, 4718 MSGQ__CREATE, &ad); 4719 if (rc) { 4720 ipc_free_security(&msq->q_perm); 4721 return rc; 4722 } 4723 return 0; 4724} 4725 4726static void selinux_msg_queue_free_security(struct msg_queue *msq) 4727{ 4728 ipc_free_security(&msq->q_perm); 4729} 4730 4731static int selinux_msg_queue_associate(struct msg_queue *msq, int msqflg) 4732{ 4733 struct ipc_security_struct *isec; 4734 struct avc_audit_data ad; 4735 u32 sid = current_sid(); 4736 4737 isec = msq->q_perm.security; 4738 4739 AVC_AUDIT_DATA_INIT(&ad, IPC); 4740 ad.u.ipc_id = msq->q_perm.key; 4741 4742 return avc_has_perm(sid, isec->sid, SECCLASS_MSGQ, 4743 MSGQ__ASSOCIATE, &ad); 4744} 4745 4746static int selinux_msg_queue_msgctl(struct msg_queue *msq, int cmd) 4747{ 4748 int err; 4749 int perms; 4750 4751 switch (cmd) { 4752 case IPC_INFO: 4753 case MSG_INFO: 4754 /* No specific object, just general system-wide information. */ 4755 return task_has_system(current, SYSTEM__IPC_INFO); 4756 case IPC_STAT: 4757 case MSG_STAT: 4758 perms = MSGQ__GETATTR | MSGQ__ASSOCIATE; 4759 break; 4760 case IPC_SET: 4761 perms = MSGQ__SETATTR; 4762 break; 4763 case IPC_RMID: 4764 perms = MSGQ__DESTROY; 4765 break; 4766 default: 4767 return 0; 4768 } 4769 4770 err = ipc_has_perm(&msq->q_perm, perms); 4771 return err; 4772} 4773 4774static int selinux_msg_queue_msgsnd(struct msg_queue *msq, struct msg_msg *msg, int msqflg) 4775{ 4776 struct ipc_security_struct *isec; 4777 struct msg_security_struct *msec; 4778 struct avc_audit_data ad; 4779 u32 sid = current_sid(); 4780 int rc; 4781 4782 isec = msq->q_perm.security; 4783 msec = msg->security; 4784 4785 /* 4786 * First time through, need to assign label to the message 4787 */ 4788 if (msec->sid == SECINITSID_UNLABELED) { 4789 /* 4790 * Compute new sid based on current process and 4791 * message queue this message will be stored in 4792 */ 4793 rc = security_transition_sid(sid, isec->sid, SECCLASS_MSG, 4794 &msec->sid); 4795 if (rc) 4796 return rc; 4797 } 4798 4799 AVC_AUDIT_DATA_INIT(&ad, IPC); 4800 ad.u.ipc_id = msq->q_perm.key; 4801 4802 /* Can this process write to the queue? */ 4803 rc = avc_has_perm(sid, isec->sid, SECCLASS_MSGQ, 4804 MSGQ__WRITE, &ad); 4805 if (!rc) 4806 /* Can this process send the message */ 4807 rc = avc_has_perm(sid, msec->sid, SECCLASS_MSG, 4808 MSG__SEND, &ad); 4809 if (!rc) 4810 /* Can the message be put in the queue? */ 4811 rc = avc_has_perm(msec->sid, isec->sid, SECCLASS_MSGQ, 4812 MSGQ__ENQUEUE, &ad); 4813 4814 return rc; 4815} 4816 4817static int selinux_msg_queue_msgrcv(struct msg_queue *msq, struct msg_msg *msg, 4818 struct task_struct *target, 4819 long type, int mode) 4820{ 4821 struct ipc_security_struct *isec; 4822 struct msg_security_struct *msec; 4823 struct avc_audit_data ad; 4824 u32 sid = task_sid(target); 4825 int rc; 4826 4827 isec = msq->q_perm.security; 4828 msec = msg->security; 4829 4830 AVC_AUDIT_DATA_INIT(&ad, IPC); 4831 ad.u.ipc_id = msq->q_perm.key; 4832 4833 rc = avc_has_perm(sid, isec->sid, 4834 SECCLASS_MSGQ, MSGQ__READ, &ad); 4835 if (!rc) 4836 rc = avc_has_perm(sid, msec->sid, 4837 SECCLASS_MSG, MSG__RECEIVE, &ad); 4838 return rc; 4839} 4840 4841/* Shared Memory security operations */ 4842static int selinux_shm_alloc_security(struct shmid_kernel *shp) 4843{ 4844 struct ipc_security_struct *isec; 4845 struct avc_audit_data ad; 4846 u32 sid = current_sid(); 4847 int rc; 4848 4849 rc = ipc_alloc_security(current, &shp->shm_perm, SECCLASS_SHM); 4850 if (rc) 4851 return rc; 4852 4853 isec = shp->shm_perm.security; 4854 4855 AVC_AUDIT_DATA_INIT(&ad, IPC); 4856 ad.u.ipc_id = shp->shm_perm.key; 4857 4858 rc = avc_has_perm(sid, isec->sid, SECCLASS_SHM, 4859 SHM__CREATE, &ad); 4860 if (rc) { 4861 ipc_free_security(&shp->shm_perm); 4862 return rc; 4863 } 4864 return 0; 4865} 4866 4867static void selinux_shm_free_security(struct shmid_kernel *shp) 4868{ 4869 ipc_free_security(&shp->shm_perm); 4870} 4871 4872static int selinux_shm_associate(struct shmid_kernel *shp, int shmflg) 4873{ 4874 struct ipc_security_struct *isec; 4875 struct avc_audit_data ad; 4876 u32 sid = current_sid(); 4877 4878 isec = shp->shm_perm.security; 4879 4880 AVC_AUDIT_DATA_INIT(&ad, IPC); 4881 ad.u.ipc_id = shp->shm_perm.key; 4882 4883 return avc_has_perm(sid, isec->sid, SECCLASS_SHM, 4884 SHM__ASSOCIATE, &ad); 4885} 4886 4887/* Note, at this point, shp is locked down */ 4888static int selinux_shm_shmctl(struct shmid_kernel *shp, int cmd) 4889{ 4890 int perms; 4891 int err; 4892 4893 switch (cmd) { 4894 case IPC_INFO: 4895 case SHM_INFO: 4896 /* No specific object, just general system-wide information. */ 4897 return task_has_system(current, SYSTEM__IPC_INFO); 4898 case IPC_STAT: 4899 case SHM_STAT: 4900 perms = SHM__GETATTR | SHM__ASSOCIATE; 4901 break; 4902 case IPC_SET: 4903 perms = SHM__SETATTR; 4904 break; 4905 case SHM_LOCK: 4906 case SHM_UNLOCK: 4907 perms = SHM__LOCK; 4908 break; 4909 case IPC_RMID: 4910 perms = SHM__DESTROY; 4911 break; 4912 default: 4913 return 0; 4914 } 4915 4916 err = ipc_has_perm(&shp->shm_perm, perms); 4917 return err; 4918} 4919 4920static int selinux_shm_shmat(struct shmid_kernel *shp, 4921 char __user *shmaddr, int shmflg) 4922{ 4923 u32 perms; 4924 4925 if (shmflg & SHM_RDONLY) 4926 perms = SHM__READ; 4927 else 4928 perms = SHM__READ | SHM__WRITE; 4929 4930 return ipc_has_perm(&shp->shm_perm, perms); 4931} 4932 4933/* Semaphore security operations */ 4934static int selinux_sem_alloc_security(struct sem_array *sma) 4935{ 4936 struct ipc_security_struct *isec; 4937 struct avc_audit_data ad; 4938 u32 sid = current_sid(); 4939 int rc; 4940 4941 rc = ipc_alloc_security(current, &sma->sem_perm, SECCLASS_SEM); 4942 if (rc) 4943 return rc; 4944 4945 isec = sma->sem_perm.security; 4946 4947 AVC_AUDIT_DATA_INIT(&ad, IPC); 4948 ad.u.ipc_id = sma->sem_perm.key; 4949 4950 rc = avc_has_perm(sid, isec->sid, SECCLASS_SEM, 4951 SEM__CREATE, &ad); 4952 if (rc) { 4953 ipc_free_security(&sma->sem_perm); 4954 return rc; 4955 } 4956 return 0; 4957} 4958 4959static void selinux_sem_free_security(struct sem_array *sma) 4960{ 4961 ipc_free_security(&sma->sem_perm); 4962} 4963 4964static int selinux_sem_associate(struct sem_array *sma, int semflg) 4965{ 4966 struct ipc_security_struct *isec; 4967 struct avc_audit_data ad; 4968 u32 sid = current_sid(); 4969 4970 isec = sma->sem_perm.security; 4971 4972 AVC_AUDIT_DATA_INIT(&ad, IPC); 4973 ad.u.ipc_id = sma->sem_perm.key; 4974 4975 return avc_has_perm(sid, isec->sid, SECCLASS_SEM, 4976 SEM__ASSOCIATE, &ad); 4977} 4978 4979/* Note, at this point, sma is locked down */ 4980static int selinux_sem_semctl(struct sem_array *sma, int cmd) 4981{ 4982 int err; 4983 u32 perms; 4984 4985 switch (cmd) { 4986 case IPC_INFO: 4987 case SEM_INFO: 4988 /* No specific object, just general system-wide information. */ 4989 return task_has_system(current, SYSTEM__IPC_INFO); 4990 case GETPID: 4991 case GETNCNT: 4992 case GETZCNT: 4993 perms = SEM__GETATTR; 4994 break; 4995 case GETVAL: 4996 case GETALL: 4997 perms = SEM__READ; 4998 break; 4999 case SETVAL: 5000 case SETALL: 5001 perms = SEM__WRITE; 5002 break; 5003 case IPC_RMID: 5004 perms = SEM__DESTROY; 5005 break; 5006 case IPC_SET: 5007 perms = SEM__SETATTR; 5008 break; 5009 case IPC_STAT: 5010 case SEM_STAT: 5011 perms = SEM__GETATTR | SEM__ASSOCIATE; 5012 break; 5013 default: 5014 return 0; 5015 } 5016 5017 err = ipc_has_perm(&sma->sem_perm, perms); 5018 return err; 5019} 5020 5021static int selinux_sem_semop(struct sem_array *sma, 5022 struct sembuf *sops, unsigned nsops, int alter) 5023{ 5024 u32 perms; 5025 5026 if (alter) 5027 perms = SEM__READ | SEM__WRITE; 5028 else 5029 perms = SEM__READ; 5030 5031 return ipc_has_perm(&sma->sem_perm, perms); 5032} 5033 5034static int selinux_ipc_permission(struct kern_ipc_perm *ipcp, short flag) 5035{ 5036 u32 av = 0; 5037 5038 av = 0; 5039 if (flag & S_IRUGO) 5040 av |= IPC__UNIX_READ; 5041 if (flag & S_IWUGO) 5042 av |= IPC__UNIX_WRITE; 5043 5044 if (av == 0) 5045 return 0; 5046 5047 return ipc_has_perm(ipcp, av); 5048} 5049 5050static void selinux_ipc_getsecid(struct kern_ipc_perm *ipcp, u32 *secid) 5051{ 5052 struct ipc_security_struct *isec = ipcp->security; 5053 *secid = isec->sid; 5054} 5055 5056static void selinux_d_instantiate(struct dentry *dentry, struct inode *inode) 5057{ 5058 if (inode) 5059 inode_doinit_with_dentry(inode, dentry); 5060} 5061 5062static int selinux_getprocattr(struct task_struct *p, 5063 char *name, char **value) 5064{ 5065 const struct task_security_struct *__tsec; 5066 u32 sid; 5067 int error; 5068 unsigned len; 5069 5070 if (current != p) { 5071 error = current_has_perm(p, PROCESS__GETATTR); 5072 if (error) 5073 return error; 5074 } 5075 5076 rcu_read_lock(); 5077 __tsec = __task_cred(p)->security; 5078 5079 if (!strcmp(name, "current")) 5080 sid = __tsec->sid; 5081 else if (!strcmp(name, "prev")) 5082 sid = __tsec->osid; 5083 else if (!strcmp(name, "exec")) 5084 sid = __tsec->exec_sid; 5085 else if (!strcmp(name, "fscreate")) 5086 sid = __tsec->create_sid; 5087 else if (!strcmp(name, "keycreate")) 5088 sid = __tsec->keycreate_sid; 5089 else if (!strcmp(name, "sockcreate")) 5090 sid = __tsec->sockcreate_sid; 5091 else 5092 goto invalid; 5093 rcu_read_unlock(); 5094 5095 if (!sid) 5096 return 0; 5097 5098 error = security_sid_to_context(sid, value, &len); 5099 if (error) 5100 return error; 5101 return len; 5102 5103invalid: 5104 rcu_read_unlock(); 5105 return -EINVAL; 5106} 5107 5108static int selinux_setprocattr(struct task_struct *p, 5109 char *name, void *value, size_t size) 5110{ 5111 struct task_security_struct *tsec; 5112 struct task_struct *tracer; 5113 struct cred *new; 5114 u32 sid = 0, ptsid; 5115 int error; 5116 char *str = value; 5117 5118 if (current != p) { 5119 /* SELinux only allows a process to change its own 5120 security attributes. */ 5121 return -EACCES; 5122 } 5123 5124 /* 5125 * Basic control over ability to set these attributes at all. 5126 * current == p, but we'll pass them separately in case the 5127 * above restriction is ever removed. 5128 */ 5129 if (!strcmp(name, "exec")) 5130 error = current_has_perm(p, PROCESS__SETEXEC); 5131 else if (!strcmp(name, "fscreate")) 5132 error = current_has_perm(p, PROCESS__SETFSCREATE); 5133 else if (!strcmp(name, "keycreate")) 5134 error = current_has_perm(p, PROCESS__SETKEYCREATE); 5135 else if (!strcmp(name, "sockcreate")) 5136 error = current_has_perm(p, PROCESS__SETSOCKCREATE); 5137 else if (!strcmp(name, "current")) 5138 error = current_has_perm(p, PROCESS__SETCURRENT); 5139 else 5140 error = -EINVAL; 5141 if (error) 5142 return error; 5143 5144 /* Obtain a SID for the context, if one was specified. */ 5145 if (size && str[1] && str[1] != '\n') { 5146 if (str[size-1] == '\n') { 5147 str[size-1] = 0; 5148 size--; 5149 } 5150 error = security_context_to_sid(value, size, &sid); 5151 if (error == -EINVAL && !strcmp(name, "fscreate")) { 5152 if (!capable(CAP_MAC_ADMIN)) 5153 return error; 5154 error = security_context_to_sid_force(value, size, 5155 &sid); 5156 } 5157 if (error) 5158 return error; 5159 } 5160 5161 new = prepare_creds(); 5162 if (!new) 5163 return -ENOMEM; 5164 5165 /* Permission checking based on the specified context is 5166 performed during the actual operation (execve, 5167 open/mkdir/...), when we know the full context of the 5168 operation. See selinux_bprm_set_creds for the execve 5169 checks and may_create for the file creation checks. The 5170 operation will then fail if the context is not permitted. */ 5171 tsec = new->security; 5172 if (!strcmp(name, "exec")) { 5173 tsec->exec_sid = sid; 5174 } else if (!strcmp(name, "fscreate")) { 5175 tsec->create_sid = sid; 5176 } else if (!strcmp(name, "keycreate")) { 5177 error = may_create_key(sid, p); 5178 if (error) 5179 goto abort_change; 5180 tsec->keycreate_sid = sid; 5181 } else if (!strcmp(name, "sockcreate")) { 5182 tsec->sockcreate_sid = sid; 5183 } else if (!strcmp(name, "current")) { 5184 error = -EINVAL; 5185 if (sid == 0) 5186 goto abort_change; 5187 5188 /* Only allow single threaded processes to change context */ 5189 error = -EPERM; 5190 if (!is_single_threaded(p)) { 5191 error = security_bounded_transition(tsec->sid, sid); 5192 if (error) 5193 goto abort_change; 5194 } 5195 5196 /* Check permissions for the transition. */ 5197 error = avc_has_perm(tsec->sid, sid, SECCLASS_PROCESS, 5198 PROCESS__DYNTRANSITION, NULL); 5199 if (error) 5200 goto abort_change; 5201 5202 /* Check for ptracing, and update the task SID if ok. 5203 Otherwise, leave SID unchanged and fail. */ 5204 ptsid = 0; 5205 task_lock(p); 5206 tracer = tracehook_tracer_task(p); 5207 if (tracer) 5208 ptsid = task_sid(tracer); 5209 task_unlock(p); 5210 5211 if (tracer) { 5212 error = avc_has_perm(ptsid, sid, SECCLASS_PROCESS, 5213 PROCESS__PTRACE, NULL); 5214 if (error) 5215 goto abort_change; 5216 } 5217 5218 tsec->sid = sid; 5219 } else { 5220 error = -EINVAL; 5221 goto abort_change; 5222 } 5223 5224 commit_creds(new); 5225 return size; 5226 5227abort_change: 5228 abort_creds(new); 5229 return error; 5230} 5231 5232static int selinux_secid_to_secctx(u32 secid, char **secdata, u32 *seclen) 5233{ 5234 return security_sid_to_context(secid, secdata, seclen); 5235} 5236 5237static int selinux_secctx_to_secid(const char *secdata, u32 seclen, u32 *secid) 5238{ 5239 return security_context_to_sid(secdata, seclen, secid); 5240} 5241 5242static void selinux_release_secctx(char *secdata, u32 seclen) 5243{ 5244 kfree(secdata); 5245} 5246 5247#ifdef CONFIG_KEYS 5248 5249static int selinux_key_alloc(struct key *k, const struct cred *cred, 5250 unsigned long flags) 5251{ 5252 const struct task_security_struct *tsec; 5253 struct key_security_struct *ksec; 5254 5255 ksec = kzalloc(sizeof(struct key_security_struct), GFP_KERNEL); 5256 if (!ksec) 5257 return -ENOMEM; 5258 5259 tsec = cred->security; 5260 if (tsec->keycreate_sid) 5261 ksec->sid = tsec->keycreate_sid; 5262 else 5263 ksec->sid = tsec->sid; 5264 5265 k->security = ksec; 5266 return 0; 5267} 5268 5269static void selinux_key_free(struct key *k) 5270{ 5271 struct key_security_struct *ksec = k->security; 5272 5273 k->security = NULL; 5274 kfree(ksec); 5275} 5276 5277static int selinux_key_permission(key_ref_t key_ref, 5278 const struct cred *cred, 5279 key_perm_t perm) 5280{ 5281 struct key *key; 5282 struct key_security_struct *ksec; 5283 u32 sid; 5284 5285 /* if no specific permissions are requested, we skip the 5286 permission check. No serious, additional covert channels 5287 appear to be created. */ 5288 if (perm == 0) 5289 return 0; 5290 5291 sid = cred_sid(cred); 5292 5293 key = key_ref_to_ptr(key_ref); 5294 ksec = key->security; 5295 5296 return avc_has_perm(sid, ksec->sid, SECCLASS_KEY, perm, NULL); 5297} 5298 5299static int selinux_key_getsecurity(struct key *key, char **_buffer) 5300{ 5301 struct key_security_struct *ksec = key->security; 5302 char *context = NULL; 5303 unsigned len; 5304 int rc; 5305 5306 rc = security_sid_to_context(ksec->sid, &context, &len); 5307 if (!rc) 5308 rc = len; 5309 *_buffer = context; 5310 return rc; 5311} 5312 5313#endif 5314 5315static struct security_operations selinux_ops = { 5316 .name = "selinux", 5317 5318 .ptrace_access_check = selinux_ptrace_access_check, 5319 .ptrace_traceme = selinux_ptrace_traceme, 5320 .capget = selinux_capget, 5321 .capset = selinux_capset, 5322 .sysctl = selinux_sysctl, 5323 .capable = selinux_capable, 5324 .quotactl = selinux_quotactl, 5325 .quota_on = selinux_quota_on, 5326 .syslog = selinux_syslog, 5327 .vm_enough_memory = selinux_vm_enough_memory, 5328 5329 .netlink_send = selinux_netlink_send, 5330 .netlink_recv = selinux_netlink_recv, 5331 5332 .bprm_set_creds = selinux_bprm_set_creds, 5333 .bprm_committing_creds = selinux_bprm_committing_creds, 5334 .bprm_committed_creds = selinux_bprm_committed_creds, 5335 .bprm_secureexec = selinux_bprm_secureexec, 5336 5337 .sb_alloc_security = selinux_sb_alloc_security, 5338 .sb_free_security = selinux_sb_free_security, 5339 .sb_copy_data = selinux_sb_copy_data, 5340 .sb_kern_mount = selinux_sb_kern_mount, 5341 .sb_show_options = selinux_sb_show_options, 5342 .sb_statfs = selinux_sb_statfs, 5343 .sb_mount = selinux_mount, 5344 .sb_umount = selinux_umount, 5345 .sb_set_mnt_opts = selinux_set_mnt_opts, 5346 .sb_clone_mnt_opts = selinux_sb_clone_mnt_opts, 5347 .sb_parse_opts_str = selinux_parse_opts_str, 5348 5349 5350 .inode_alloc_security = selinux_inode_alloc_security, 5351 .inode_free_security = selinux_inode_free_security, 5352 .inode_init_security = selinux_inode_init_security, 5353 .inode_create = selinux_inode_create, 5354 .inode_link = selinux_inode_link, 5355 .inode_unlink = selinux_inode_unlink, 5356 .inode_symlink = selinux_inode_symlink, 5357 .inode_mkdir = selinux_inode_mkdir, 5358 .inode_rmdir = selinux_inode_rmdir, 5359 .inode_mknod = selinux_inode_mknod, 5360 .inode_rename = selinux_inode_rename, 5361 .inode_readlink = selinux_inode_readlink, 5362 .inode_follow_link = selinux_inode_follow_link, 5363 .inode_permission = selinux_inode_permission, 5364 .inode_setattr = selinux_inode_setattr, 5365 .inode_getattr = selinux_inode_getattr, 5366 .inode_setxattr = selinux_inode_setxattr, 5367 .inode_post_setxattr = selinux_inode_post_setxattr, 5368 .inode_getxattr = selinux_inode_getxattr, 5369 .inode_listxattr = selinux_inode_listxattr, 5370 .inode_removexattr = selinux_inode_removexattr, 5371 .inode_getsecurity = selinux_inode_getsecurity, 5372 .inode_setsecurity = selinux_inode_setsecurity, 5373 .inode_listsecurity = selinux_inode_listsecurity, 5374 .inode_getsecid = selinux_inode_getsecid, 5375 5376 .file_permission = selinux_file_permission, 5377 .file_alloc_security = selinux_file_alloc_security, 5378 .file_free_security = selinux_file_free_security, 5379 .file_ioctl = selinux_file_ioctl, 5380 .file_mmap = selinux_file_mmap, 5381 .file_mprotect = selinux_file_mprotect, 5382 .file_lock = selinux_file_lock, 5383 .file_fcntl = selinux_file_fcntl, 5384 .file_set_fowner = selinux_file_set_fowner, 5385 .file_send_sigiotask = selinux_file_send_sigiotask, 5386 .file_receive = selinux_file_receive, 5387 5388 .dentry_open = selinux_dentry_open, 5389 5390 .task_create = selinux_task_create, 5391 .cred_free = selinux_cred_free, 5392 .cred_prepare = selinux_cred_prepare, 5393 .kernel_act_as = selinux_kernel_act_as, 5394 .kernel_create_files_as = selinux_kernel_create_files_as, 5395 .task_setpgid = selinux_task_setpgid, 5396 .task_getpgid = selinux_task_getpgid, 5397 .task_getsid = selinux_task_getsid, 5398 .task_getsecid = selinux_task_getsecid, 5399 .task_setnice = selinux_task_setnice, 5400 .task_setioprio = selinux_task_setioprio, 5401 .task_getioprio = selinux_task_getioprio, 5402 .task_setrlimit = selinux_task_setrlimit, 5403 .task_setscheduler = selinux_task_setscheduler, 5404 .task_getscheduler = selinux_task_getscheduler, 5405 .task_movememory = selinux_task_movememory, 5406 .task_kill = selinux_task_kill, 5407 .task_wait = selinux_task_wait, 5408 .task_to_inode = selinux_task_to_inode, 5409 5410 .ipc_permission = selinux_ipc_permission, 5411 .ipc_getsecid = selinux_ipc_getsecid, 5412 5413 .msg_msg_alloc_security = selinux_msg_msg_alloc_security, 5414 .msg_msg_free_security = selinux_msg_msg_free_security, 5415 5416 .msg_queue_alloc_security = selinux_msg_queue_alloc_security, 5417 .msg_queue_free_security = selinux_msg_queue_free_security, 5418 .msg_queue_associate = selinux_msg_queue_associate, 5419 .msg_queue_msgctl = selinux_msg_queue_msgctl, 5420 .msg_queue_msgsnd = selinux_msg_queue_msgsnd, 5421 .msg_queue_msgrcv = selinux_msg_queue_msgrcv, 5422 5423 .shm_alloc_security = selinux_shm_alloc_security, 5424 .shm_free_security = selinux_shm_free_security, 5425 .shm_associate = selinux_shm_associate, 5426 .shm_shmctl = selinux_shm_shmctl, 5427 .shm_shmat = selinux_shm_shmat, 5428 5429 .sem_alloc_security = selinux_sem_alloc_security, 5430 .sem_free_security = selinux_sem_free_security, 5431 .sem_associate = selinux_sem_associate, 5432 .sem_semctl = selinux_sem_semctl, 5433 .sem_semop = selinux_sem_semop, 5434 5435 .d_instantiate = selinux_d_instantiate, 5436 5437 .getprocattr = selinux_getprocattr, 5438 .setprocattr = selinux_setprocattr, 5439 5440 .secid_to_secctx = selinux_secid_to_secctx, 5441 .secctx_to_secid = selinux_secctx_to_secid, 5442 .release_secctx = selinux_release_secctx, 5443 5444 .unix_stream_connect = selinux_socket_unix_stream_connect, 5445 .unix_may_send = selinux_socket_unix_may_send, 5446 5447 .socket_create = selinux_socket_create, 5448 .socket_post_create = selinux_socket_post_create, 5449 .socket_bind = selinux_socket_bind, 5450 .socket_connect = selinux_socket_connect, 5451 .socket_listen = selinux_socket_listen, 5452 .socket_accept = selinux_socket_accept, 5453 .socket_sendmsg = selinux_socket_sendmsg, 5454 .socket_recvmsg = selinux_socket_recvmsg, 5455 .socket_getsockname = selinux_socket_getsockname, 5456 .socket_getpeername = selinux_socket_getpeername, 5457 .socket_getsockopt = selinux_socket_getsockopt, 5458 .socket_setsockopt = selinux_socket_setsockopt, 5459 .socket_shutdown = selinux_socket_shutdown, 5460 .socket_sock_rcv_skb = selinux_socket_sock_rcv_skb, 5461 .socket_getpeersec_stream = selinux_socket_getpeersec_stream, 5462 .socket_getpeersec_dgram = selinux_socket_getpeersec_dgram, 5463 .sk_alloc_security = selinux_sk_alloc_security, 5464 .sk_free_security = selinux_sk_free_security, 5465 .sk_clone_security = selinux_sk_clone_security, 5466 .sk_getsecid = selinux_sk_getsecid, 5467 .sock_graft = selinux_sock_graft, 5468 .inet_conn_request = selinux_inet_conn_request, 5469 .inet_csk_clone = selinux_inet_csk_clone, 5470 .inet_conn_established = selinux_inet_conn_established, 5471 .req_classify_flow = selinux_req_classify_flow, 5472 5473#ifdef CONFIG_SECURITY_NETWORK_XFRM 5474 .xfrm_policy_alloc_security = selinux_xfrm_policy_alloc, 5475 .xfrm_policy_clone_security = selinux_xfrm_policy_clone, 5476 .xfrm_policy_free_security = selinux_xfrm_policy_free, 5477 .xfrm_policy_delete_security = selinux_xfrm_policy_delete, 5478 .xfrm_state_alloc_security = selinux_xfrm_state_alloc, 5479 .xfrm_state_free_security = selinux_xfrm_state_free, 5480 .xfrm_state_delete_security = selinux_xfrm_state_delete, 5481 .xfrm_policy_lookup = selinux_xfrm_policy_lookup, 5482 .xfrm_state_pol_flow_match = selinux_xfrm_state_pol_flow_match, 5483 .xfrm_decode_session = selinux_xfrm_decode_session, 5484#endif 5485 5486#ifdef CONFIG_KEYS 5487 .key_alloc = selinux_key_alloc, 5488 .key_free = selinux_key_free, 5489 .key_permission = selinux_key_permission, 5490 .key_getsecurity = selinux_key_getsecurity, 5491#endif 5492 5493#ifdef CONFIG_AUDIT 5494 .audit_rule_init = selinux_audit_rule_init, 5495 .audit_rule_known = selinux_audit_rule_known, 5496 .audit_rule_match = selinux_audit_rule_match, 5497 .audit_rule_free = selinux_audit_rule_free, 5498#endif 5499}; 5500 5501static __init int selinux_init(void) 5502{ 5503 if (!security_module_enable(&selinux_ops)) { 5504 selinux_enabled = 0; 5505 return 0; 5506 } 5507 5508 if (!selinux_enabled) { 5509 printk(KERN_INFO "SELinux: Disabled at boot.\n"); 5510 return 0; 5511 } 5512 5513 printk(KERN_INFO "SELinux: Initializing.\n"); 5514 5515 /* Set the security state for the initial task. */ 5516 cred_init_security(); 5517 5518 sel_inode_cache = kmem_cache_create("selinux_inode_security", 5519 sizeof(struct inode_security_struct), 5520 0, SLAB_PANIC, NULL); 5521 avc_init(); 5522 5523 secondary_ops = security_ops; 5524 if (!secondary_ops) 5525 panic("SELinux: No initial security operations\n"); 5526 if (register_security(&selinux_ops)) 5527 panic("SELinux: Unable to register with kernel.\n"); 5528 5529 if (selinux_enforcing) 5530 printk(KERN_DEBUG "SELinux: Starting in enforcing mode\n"); 5531 else 5532 printk(KERN_DEBUG "SELinux: Starting in permissive mode\n"); 5533 5534 return 0; 5535} 5536 5537void selinux_complete_init(void) 5538{ 5539 printk(KERN_DEBUG "SELinux: Completing initialization.\n"); 5540 5541 /* Set up any superblocks initialized prior to the policy load. */ 5542 printk(KERN_DEBUG "SELinux: Setting up existing superblocks.\n"); 5543 spin_lock(&sb_lock); 5544 spin_lock(&sb_security_lock); 5545next_sb: 5546 if (!list_empty(&superblock_security_head)) { 5547 struct superblock_security_struct *sbsec = 5548 list_entry(superblock_security_head.next, 5549 struct superblock_security_struct, 5550 list); 5551 struct super_block *sb = sbsec->sb; 5552 sb->s_count++; 5553 spin_unlock(&sb_security_lock); 5554 spin_unlock(&sb_lock); 5555 down_read(&sb->s_umount); 5556 if (sb->s_root) 5557 superblock_doinit(sb, NULL); 5558 drop_super(sb); 5559 spin_lock(&sb_lock); 5560 spin_lock(&sb_security_lock); 5561 list_del_init(&sbsec->list); 5562 goto next_sb; 5563 } 5564 spin_unlock(&sb_security_lock); 5565 spin_unlock(&sb_lock); 5566} 5567 5568/* SELinux requires early initialization in order to label 5569 all processes and objects when they are created. */ 5570security_initcall(selinux_init); 5571 5572#if defined(CONFIG_NETFILTER) 5573 5574static struct nf_hook_ops selinux_ipv4_ops[] = { 5575 { 5576 .hook = selinux_ipv4_postroute, 5577 .owner = THIS_MODULE, 5578 .pf = PF_INET, 5579 .hooknum = NF_INET_POST_ROUTING, 5580 .priority = NF_IP_PRI_SELINUX_LAST, 5581 }, 5582 { 5583 .hook = selinux_ipv4_forward, 5584 .owner = THIS_MODULE, 5585 .pf = PF_INET, 5586 .hooknum = NF_INET_FORWARD, 5587 .priority = NF_IP_PRI_SELINUX_FIRST, 5588 }, 5589 { 5590 .hook = selinux_ipv4_output, 5591 .owner = THIS_MODULE, 5592 .pf = PF_INET, 5593 .hooknum = NF_INET_LOCAL_OUT, 5594 .priority = NF_IP_PRI_SELINUX_FIRST, 5595 } 5596}; 5597 5598#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE) 5599 5600static struct nf_hook_ops selinux_ipv6_ops[] = { 5601 { 5602 .hook = selinux_ipv6_postroute, 5603 .owner = THIS_MODULE, 5604 .pf = PF_INET6, 5605 .hooknum = NF_INET_POST_ROUTING, 5606 .priority = NF_IP6_PRI_SELINUX_LAST, 5607 }, 5608 { 5609 .hook = selinux_ipv6_forward, 5610 .owner = THIS_MODULE, 5611 .pf = PF_INET6, 5612 .hooknum = NF_INET_FORWARD, 5613 .priority = NF_IP6_PRI_SELINUX_FIRST, 5614 } 5615}; 5616 5617#endif /* IPV6 */ 5618 5619static int __init selinux_nf_ip_init(void) 5620{ 5621 int err = 0; 5622 5623 if (!selinux_enabled) 5624 goto out; 5625 5626 printk(KERN_DEBUG "SELinux: Registering netfilter hooks\n"); 5627 5628 err = nf_register_hooks(selinux_ipv4_ops, ARRAY_SIZE(selinux_ipv4_ops)); 5629 if (err) 5630 panic("SELinux: nf_register_hooks for IPv4: error %d\n", err); 5631 5632#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE) 5633 err = nf_register_hooks(selinux_ipv6_ops, ARRAY_SIZE(selinux_ipv6_ops)); 5634 if (err) 5635 panic("SELinux: nf_register_hooks for IPv6: error %d\n", err); 5636#endif /* IPV6 */ 5637 5638out: 5639 return err; 5640} 5641 5642__initcall(selinux_nf_ip_init); 5643 5644#ifdef CONFIG_SECURITY_SELINUX_DISABLE 5645static void selinux_nf_ip_exit(void) 5646{ 5647 printk(KERN_DEBUG "SELinux: Unregistering netfilter hooks\n"); 5648 5649 nf_unregister_hooks(selinux_ipv4_ops, ARRAY_SIZE(selinux_ipv4_ops)); 5650#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE) 5651 nf_unregister_hooks(selinux_ipv6_ops, ARRAY_SIZE(selinux_ipv6_ops)); 5652#endif /* IPV6 */ 5653} 5654#endif 5655 5656#else /* CONFIG_NETFILTER */ 5657 5658#ifdef CONFIG_SECURITY_SELINUX_DISABLE 5659#define selinux_nf_ip_exit() 5660#endif 5661 5662#endif /* CONFIG_NETFILTER */ 5663 5664#ifdef CONFIG_SECURITY_SELINUX_DISABLE 5665static int selinux_disabled; 5666 5667int selinux_disable(void) 5668{ 5669 extern void exit_sel_fs(void); 5670 5671 if (ss_initialized) { 5672 /* Not permitted after initial policy load. */ 5673 return -EINVAL; 5674 } 5675 5676 if (selinux_disabled) { 5677 /* Only do this once. */ 5678 return -EINVAL; 5679 } 5680 5681 printk(KERN_INFO "SELinux: Disabled at runtime.\n"); 5682 5683 selinux_disabled = 1; 5684 selinux_enabled = 0; 5685 5686 /* Try to destroy the avc node cache */ 5687 avc_disable(); 5688 5689 /* Reset security_ops to the secondary module, dummy or capability. */ 5690 security_ops = secondary_ops; 5691 5692 /* Unregister netfilter hooks. */ 5693 selinux_nf_ip_exit(); 5694 5695 /* Unregister selinuxfs. */ 5696 exit_sel_fs(); 5697 5698 return 0; 5699} 5700#endif 5701