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 79 #include "avc.h" 80 #include "objsec.h" 81 #include "netif.h" 82 #include "netnode.h" 83 #include "netport.h" 84 #include "xfrm.h" 85 #include "netlabel.h" 86 #include "audit.h" 87 88 #define XATTR_SELINUX_SUFFIX "selinux" 89 #define XATTR_NAME_SELINUX XATTR_SECURITY_PREFIX XATTR_SELINUX_SUFFIX 90 91 #define NUM_SEL_MNT_OPTS 4 92 93 extern unsigned int policydb_loaded_version; 94 extern int selinux_nlmsg_lookup(u16 sclass, u16 nlmsg_type, u32 *perm); 95 extern int selinux_compat_net; 96 extern struct security_operations *security_ops; 97 98 /* SECMARK reference count */ 99 atomic_t selinux_secmark_refcount = ATOMIC_INIT(0); 100 101 #ifdef CONFIG_SECURITY_SELINUX_DEVELOP 102 int selinux_enforcing; 103 104 static 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 115 int selinux_enabled = CONFIG_SECURITY_SELINUX_BOOTPARAM_VALUE; 116 117 static 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 126 int 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 */ 134 static struct security_operations *secondary_ops; 135 136 /* Lists of inode and superblock security structures initialized 137 before the policy was loaded. */ 138 static LIST_HEAD(superblock_security_head); 139 static DEFINE_SPINLOCK(sb_security_lock); 140 141 static 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 */ 153 static int selinux_secmark_enabled(void) 154 { 155 return (atomic_read(&selinux_secmark_refcount) > 0); 156 } 157 158 /* Allocate and free functions for each kind of security blob. */ 159 160 static int task_alloc_security(struct task_struct *task) 161 { 162 struct task_security_struct *tsec; 163 164 tsec = kzalloc(sizeof(struct task_security_struct), GFP_KERNEL); 165 if (!tsec) 166 return -ENOMEM; 167 168 tsec->osid = tsec->sid = SECINITSID_UNLABELED; 169 task->security = tsec; 170 171 return 0; 172 } 173 174 static void task_free_security(struct task_struct *task) 175 { 176 struct task_security_struct *tsec = task->security; 177 task->security = NULL; 178 kfree(tsec); 179 } 180 181 static int inode_alloc_security(struct inode *inode) 182 { 183 struct task_security_struct *tsec = current->security; 184 struct inode_security_struct *isec; 185 186 isec = kmem_cache_zalloc(sel_inode_cache, GFP_NOFS); 187 if (!isec) 188 return -ENOMEM; 189 190 mutex_init(&isec->lock); 191 INIT_LIST_HEAD(&isec->list); 192 isec->inode = inode; 193 isec->sid = SECINITSID_UNLABELED; 194 isec->sclass = SECCLASS_FILE; 195 isec->task_sid = tsec->sid; 196 inode->i_security = isec; 197 198 return 0; 199 } 200 201 static void inode_free_security(struct inode *inode) 202 { 203 struct inode_security_struct *isec = inode->i_security; 204 struct superblock_security_struct *sbsec = inode->i_sb->s_security; 205 206 spin_lock(&sbsec->isec_lock); 207 if (!list_empty(&isec->list)) 208 list_del_init(&isec->list); 209 spin_unlock(&sbsec->isec_lock); 210 211 inode->i_security = NULL; 212 kmem_cache_free(sel_inode_cache, isec); 213 } 214 215 static int file_alloc_security(struct file *file) 216 { 217 struct task_security_struct *tsec = current->security; 218 struct file_security_struct *fsec; 219 220 fsec = kzalloc(sizeof(struct file_security_struct), GFP_KERNEL); 221 if (!fsec) 222 return -ENOMEM; 223 224 fsec->sid = tsec->sid; 225 fsec->fown_sid = tsec->sid; 226 file->f_security = fsec; 227 228 return 0; 229 } 230 231 static void file_free_security(struct file *file) 232 { 233 struct file_security_struct *fsec = file->f_security; 234 file->f_security = NULL; 235 kfree(fsec); 236 } 237 238 static int superblock_alloc_security(struct super_block *sb) 239 { 240 struct superblock_security_struct *sbsec; 241 242 sbsec = kzalloc(sizeof(struct superblock_security_struct), GFP_KERNEL); 243 if (!sbsec) 244 return -ENOMEM; 245 246 mutex_init(&sbsec->lock); 247 INIT_LIST_HEAD(&sbsec->list); 248 INIT_LIST_HEAD(&sbsec->isec_head); 249 spin_lock_init(&sbsec->isec_lock); 250 sbsec->sb = sb; 251 sbsec->sid = SECINITSID_UNLABELED; 252 sbsec->def_sid = SECINITSID_FILE; 253 sbsec->mntpoint_sid = SECINITSID_UNLABELED; 254 sb->s_security = sbsec; 255 256 return 0; 257 } 258 259 static void superblock_free_security(struct super_block *sb) 260 { 261 struct superblock_security_struct *sbsec = sb->s_security; 262 263 spin_lock(&sb_security_lock); 264 if (!list_empty(&sbsec->list)) 265 list_del_init(&sbsec->list); 266 spin_unlock(&sb_security_lock); 267 268 sb->s_security = NULL; 269 kfree(sbsec); 270 } 271 272 static int sk_alloc_security(struct sock *sk, int family, gfp_t priority) 273 { 274 struct sk_security_struct *ssec; 275 276 ssec = kzalloc(sizeof(*ssec), priority); 277 if (!ssec) 278 return -ENOMEM; 279 280 ssec->peer_sid = SECINITSID_UNLABELED; 281 ssec->sid = SECINITSID_UNLABELED; 282 sk->sk_security = ssec; 283 284 selinux_netlbl_sk_security_reset(ssec, family); 285 286 return 0; 287 } 288 289 static void sk_free_security(struct sock *sk) 290 { 291 struct sk_security_struct *ssec = sk->sk_security; 292 293 sk->sk_security = NULL; 294 kfree(ssec); 295 } 296 297 /* The security server must be initialized before 298 any labeling or access decisions can be provided. */ 299 extern int ss_initialized; 300 301 /* The file system's label must be initialized prior to use. */ 302 303 static char *labeling_behaviors[6] = { 304 "uses xattr", 305 "uses transition SIDs", 306 "uses task SIDs", 307 "uses genfs_contexts", 308 "not configured for labeling", 309 "uses mountpoint labeling", 310 }; 311 312 static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dentry); 313 314 static inline int inode_doinit(struct inode *inode) 315 { 316 return inode_doinit_with_dentry(inode, NULL); 317 } 318 319 enum { 320 Opt_error = -1, 321 Opt_context = 1, 322 Opt_fscontext = 2, 323 Opt_defcontext = 3, 324 Opt_rootcontext = 4, 325 }; 326 327 static match_table_t tokens = { 328 {Opt_context, CONTEXT_STR "%s"}, 329 {Opt_fscontext, FSCONTEXT_STR "%s"}, 330 {Opt_defcontext, DEFCONTEXT_STR "%s"}, 331 {Opt_rootcontext, ROOTCONTEXT_STR "%s"}, 332 {Opt_error, NULL}, 333 }; 334 335 #define SEL_MOUNT_FAIL_MSG "SELinux: duplicate or incompatible mount options\n" 336 337 static int may_context_mount_sb_relabel(u32 sid, 338 struct superblock_security_struct *sbsec, 339 struct task_security_struct *tsec) 340 { 341 int rc; 342 343 rc = avc_has_perm(tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM, 344 FILESYSTEM__RELABELFROM, NULL); 345 if (rc) 346 return rc; 347 348 rc = avc_has_perm(tsec->sid, sid, SECCLASS_FILESYSTEM, 349 FILESYSTEM__RELABELTO, NULL); 350 return rc; 351 } 352 353 static int may_context_mount_inode_relabel(u32 sid, 354 struct superblock_security_struct *sbsec, 355 struct task_security_struct *tsec) 356 { 357 int rc; 358 rc = avc_has_perm(tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM, 359 FILESYSTEM__RELABELFROM, NULL); 360 if (rc) 361 return rc; 362 363 rc = avc_has_perm(sid, sbsec->sid, SECCLASS_FILESYSTEM, 364 FILESYSTEM__ASSOCIATE, NULL); 365 return rc; 366 } 367 368 static int sb_finish_set_opts(struct super_block *sb) 369 { 370 struct superblock_security_struct *sbsec = sb->s_security; 371 struct dentry *root = sb->s_root; 372 struct inode *root_inode = root->d_inode; 373 int rc = 0; 374 375 if (sbsec->behavior == SECURITY_FS_USE_XATTR) { 376 /* Make sure that the xattr handler exists and that no 377 error other than -ENODATA is returned by getxattr on 378 the root directory. -ENODATA is ok, as this may be 379 the first boot of the SELinux kernel before we have 380 assigned xattr values to the filesystem. */ 381 if (!root_inode->i_op->getxattr) { 382 printk(KERN_WARNING "SELinux: (dev %s, type %s) has no " 383 "xattr support\n", sb->s_id, sb->s_type->name); 384 rc = -EOPNOTSUPP; 385 goto out; 386 } 387 rc = root_inode->i_op->getxattr(root, XATTR_NAME_SELINUX, NULL, 0); 388 if (rc < 0 && rc != -ENODATA) { 389 if (rc == -EOPNOTSUPP) 390 printk(KERN_WARNING "SELinux: (dev %s, type " 391 "%s) has no security xattr handler\n", 392 sb->s_id, sb->s_type->name); 393 else 394 printk(KERN_WARNING "SELinux: (dev %s, type " 395 "%s) getxattr errno %d\n", sb->s_id, 396 sb->s_type->name, -rc); 397 goto out; 398 } 399 } 400 401 sbsec->initialized = 1; 402 403 if (sbsec->behavior > ARRAY_SIZE(labeling_behaviors)) 404 printk(KERN_ERR "SELinux: initialized (dev %s, type %s), unknown behavior\n", 405 sb->s_id, sb->s_type->name); 406 else 407 printk(KERN_DEBUG "SELinux: initialized (dev %s, type %s), %s\n", 408 sb->s_id, sb->s_type->name, 409 labeling_behaviors[sbsec->behavior-1]); 410 411 /* Initialize the root inode. */ 412 rc = inode_doinit_with_dentry(root_inode, root); 413 414 /* Initialize any other inodes associated with the superblock, e.g. 415 inodes created prior to initial policy load or inodes created 416 during get_sb by a pseudo filesystem that directly 417 populates itself. */ 418 spin_lock(&sbsec->isec_lock); 419 next_inode: 420 if (!list_empty(&sbsec->isec_head)) { 421 struct inode_security_struct *isec = 422 list_entry(sbsec->isec_head.next, 423 struct inode_security_struct, list); 424 struct inode *inode = isec->inode; 425 spin_unlock(&sbsec->isec_lock); 426 inode = igrab(inode); 427 if (inode) { 428 if (!IS_PRIVATE(inode)) 429 inode_doinit(inode); 430 iput(inode); 431 } 432 spin_lock(&sbsec->isec_lock); 433 list_del_init(&isec->list); 434 goto next_inode; 435 } 436 spin_unlock(&sbsec->isec_lock); 437 out: 438 return rc; 439 } 440 441 /* 442 * This function should allow an FS to ask what it's mount security 443 * options were so it can use those later for submounts, displaying 444 * mount options, or whatever. 445 */ 446 static int selinux_get_mnt_opts(const struct super_block *sb, 447 struct security_mnt_opts *opts) 448 { 449 int rc = 0, i; 450 struct superblock_security_struct *sbsec = sb->s_security; 451 char *context = NULL; 452 u32 len; 453 char tmp; 454 455 security_init_mnt_opts(opts); 456 457 if (!sbsec->initialized) 458 return -EINVAL; 459 460 if (!ss_initialized) 461 return -EINVAL; 462 463 /* 464 * if we ever use sbsec flags for anything other than tracking mount 465 * settings this is going to need a mask 466 */ 467 tmp = sbsec->flags; 468 /* count the number of mount options for this sb */ 469 for (i = 0; i < 8; i++) { 470 if (tmp & 0x01) 471 opts->num_mnt_opts++; 472 tmp >>= 1; 473 } 474 475 opts->mnt_opts = kcalloc(opts->num_mnt_opts, sizeof(char *), GFP_ATOMIC); 476 if (!opts->mnt_opts) { 477 rc = -ENOMEM; 478 goto out_free; 479 } 480 481 opts->mnt_opts_flags = kcalloc(opts->num_mnt_opts, sizeof(int), GFP_ATOMIC); 482 if (!opts->mnt_opts_flags) { 483 rc = -ENOMEM; 484 goto out_free; 485 } 486 487 i = 0; 488 if (sbsec->flags & FSCONTEXT_MNT) { 489 rc = security_sid_to_context(sbsec->sid, &context, &len); 490 if (rc) 491 goto out_free; 492 opts->mnt_opts[i] = context; 493 opts->mnt_opts_flags[i++] = FSCONTEXT_MNT; 494 } 495 if (sbsec->flags & CONTEXT_MNT) { 496 rc = security_sid_to_context(sbsec->mntpoint_sid, &context, &len); 497 if (rc) 498 goto out_free; 499 opts->mnt_opts[i] = context; 500 opts->mnt_opts_flags[i++] = CONTEXT_MNT; 501 } 502 if (sbsec->flags & DEFCONTEXT_MNT) { 503 rc = security_sid_to_context(sbsec->def_sid, &context, &len); 504 if (rc) 505 goto out_free; 506 opts->mnt_opts[i] = context; 507 opts->mnt_opts_flags[i++] = DEFCONTEXT_MNT; 508 } 509 if (sbsec->flags & ROOTCONTEXT_MNT) { 510 struct inode *root = sbsec->sb->s_root->d_inode; 511 struct inode_security_struct *isec = root->i_security; 512 513 rc = security_sid_to_context(isec->sid, &context, &len); 514 if (rc) 515 goto out_free; 516 opts->mnt_opts[i] = context; 517 opts->mnt_opts_flags[i++] = ROOTCONTEXT_MNT; 518 } 519 520 BUG_ON(i != opts->num_mnt_opts); 521 522 return 0; 523 524 out_free: 525 security_free_mnt_opts(opts); 526 return rc; 527 } 528 529 static int bad_option(struct superblock_security_struct *sbsec, char flag, 530 u32 old_sid, u32 new_sid) 531 { 532 /* check if the old mount command had the same options */ 533 if (sbsec->initialized) 534 if (!(sbsec->flags & flag) || 535 (old_sid != new_sid)) 536 return 1; 537 538 /* check if we were passed the same options twice, 539 * aka someone passed context=a,context=b 540 */ 541 if (!sbsec->initialized) 542 if (sbsec->flags & flag) 543 return 1; 544 return 0; 545 } 546 547 /* 548 * Allow filesystems with binary mount data to explicitly set mount point 549 * labeling information. 550 */ 551 static int selinux_set_mnt_opts(struct super_block *sb, 552 struct security_mnt_opts *opts) 553 { 554 int rc = 0, i; 555 struct task_security_struct *tsec = current->security; 556 struct superblock_security_struct *sbsec = sb->s_security; 557 const char *name = sb->s_type->name; 558 struct inode *inode = sbsec->sb->s_root->d_inode; 559 struct inode_security_struct *root_isec = inode->i_security; 560 u32 fscontext_sid = 0, context_sid = 0, rootcontext_sid = 0; 561 u32 defcontext_sid = 0; 562 char **mount_options = opts->mnt_opts; 563 int *flags = opts->mnt_opts_flags; 564 int num_opts = opts->num_mnt_opts; 565 566 mutex_lock(&sbsec->lock); 567 568 if (!ss_initialized) { 569 if (!num_opts) { 570 /* Defer initialization until selinux_complete_init, 571 after the initial policy is loaded and the security 572 server is ready to handle calls. */ 573 spin_lock(&sb_security_lock); 574 if (list_empty(&sbsec->list)) 575 list_add(&sbsec->list, &superblock_security_head); 576 spin_unlock(&sb_security_lock); 577 goto out; 578 } 579 rc = -EINVAL; 580 printk(KERN_WARNING "SELinux: Unable to set superblock options " 581 "before the security server is initialized\n"); 582 goto out; 583 } 584 585 /* 586 * Binary mount data FS will come through this function twice. Once 587 * from an explicit call and once from the generic calls from the vfs. 588 * Since the generic VFS calls will not contain any security mount data 589 * we need to skip the double mount verification. 590 * 591 * This does open a hole in which we will not notice if the first 592 * mount using this sb set explict options and a second mount using 593 * this sb does not set any security options. (The first options 594 * will be used for both mounts) 595 */ 596 if (sbsec->initialized && (sb->s_type->fs_flags & FS_BINARY_MOUNTDATA) 597 && (num_opts == 0)) 598 goto out; 599 600 /* 601 * parse the mount options, check if they are valid sids. 602 * also check if someone is trying to mount the same sb more 603 * than once with different security options. 604 */ 605 for (i = 0; i < num_opts; i++) { 606 u32 sid; 607 rc = security_context_to_sid(mount_options[i], 608 strlen(mount_options[i]), &sid); 609 if (rc) { 610 printk(KERN_WARNING "SELinux: security_context_to_sid" 611 "(%s) failed for (dev %s, type %s) errno=%d\n", 612 mount_options[i], sb->s_id, name, rc); 613 goto out; 614 } 615 switch (flags[i]) { 616 case FSCONTEXT_MNT: 617 fscontext_sid = sid; 618 619 if (bad_option(sbsec, FSCONTEXT_MNT, sbsec->sid, 620 fscontext_sid)) 621 goto out_double_mount; 622 623 sbsec->flags |= FSCONTEXT_MNT; 624 break; 625 case CONTEXT_MNT: 626 context_sid = sid; 627 628 if (bad_option(sbsec, CONTEXT_MNT, sbsec->mntpoint_sid, 629 context_sid)) 630 goto out_double_mount; 631 632 sbsec->flags |= CONTEXT_MNT; 633 break; 634 case ROOTCONTEXT_MNT: 635 rootcontext_sid = sid; 636 637 if (bad_option(sbsec, ROOTCONTEXT_MNT, root_isec->sid, 638 rootcontext_sid)) 639 goto out_double_mount; 640 641 sbsec->flags |= ROOTCONTEXT_MNT; 642 643 break; 644 case DEFCONTEXT_MNT: 645 defcontext_sid = sid; 646 647 if (bad_option(sbsec, DEFCONTEXT_MNT, sbsec->def_sid, 648 defcontext_sid)) 649 goto out_double_mount; 650 651 sbsec->flags |= DEFCONTEXT_MNT; 652 653 break; 654 default: 655 rc = -EINVAL; 656 goto out; 657 } 658 } 659 660 if (sbsec->initialized) { 661 /* previously mounted with options, but not on this attempt? */ 662 if (sbsec->flags && !num_opts) 663 goto out_double_mount; 664 rc = 0; 665 goto out; 666 } 667 668 if (strcmp(sb->s_type->name, "proc") == 0) 669 sbsec->proc = 1; 670 671 /* Determine the labeling behavior to use for this filesystem type. */ 672 rc = security_fs_use(sb->s_type->name, &sbsec->behavior, &sbsec->sid); 673 if (rc) { 674 printk(KERN_WARNING "%s: security_fs_use(%s) returned %d\n", 675 __func__, sb->s_type->name, rc); 676 goto out; 677 } 678 679 /* sets the context of the superblock for the fs being mounted. */ 680 if (fscontext_sid) { 681 682 rc = may_context_mount_sb_relabel(fscontext_sid, sbsec, tsec); 683 if (rc) 684 goto out; 685 686 sbsec->sid = fscontext_sid; 687 } 688 689 /* 690 * Switch to using mount point labeling behavior. 691 * sets the label used on all file below the mountpoint, and will set 692 * the superblock context if not already set. 693 */ 694 if (context_sid) { 695 if (!fscontext_sid) { 696 rc = may_context_mount_sb_relabel(context_sid, sbsec, tsec); 697 if (rc) 698 goto out; 699 sbsec->sid = context_sid; 700 } else { 701 rc = may_context_mount_inode_relabel(context_sid, sbsec, tsec); 702 if (rc) 703 goto out; 704 } 705 if (!rootcontext_sid) 706 rootcontext_sid = context_sid; 707 708 sbsec->mntpoint_sid = context_sid; 709 sbsec->behavior = SECURITY_FS_USE_MNTPOINT; 710 } 711 712 if (rootcontext_sid) { 713 rc = may_context_mount_inode_relabel(rootcontext_sid, sbsec, tsec); 714 if (rc) 715 goto out; 716 717 root_isec->sid = rootcontext_sid; 718 root_isec->initialized = 1; 719 } 720 721 if (defcontext_sid) { 722 if (sbsec->behavior != SECURITY_FS_USE_XATTR) { 723 rc = -EINVAL; 724 printk(KERN_WARNING "SELinux: defcontext option is " 725 "invalid for this filesystem type\n"); 726 goto out; 727 } 728 729 if (defcontext_sid != sbsec->def_sid) { 730 rc = may_context_mount_inode_relabel(defcontext_sid, 731 sbsec, tsec); 732 if (rc) 733 goto out; 734 } 735 736 sbsec->def_sid = defcontext_sid; 737 } 738 739 rc = sb_finish_set_opts(sb); 740 out: 741 mutex_unlock(&sbsec->lock); 742 return rc; 743 out_double_mount: 744 rc = -EINVAL; 745 printk(KERN_WARNING "SELinux: mount invalid. Same superblock, different " 746 "security settings for (dev %s, type %s)\n", sb->s_id, name); 747 goto out; 748 } 749 750 static void selinux_sb_clone_mnt_opts(const struct super_block *oldsb, 751 struct super_block *newsb) 752 { 753 const struct superblock_security_struct *oldsbsec = oldsb->s_security; 754 struct superblock_security_struct *newsbsec = newsb->s_security; 755 756 int set_fscontext = (oldsbsec->flags & FSCONTEXT_MNT); 757 int set_context = (oldsbsec->flags & CONTEXT_MNT); 758 int set_rootcontext = (oldsbsec->flags & ROOTCONTEXT_MNT); 759 760 /* 761 * if the parent was able to be mounted it clearly had no special lsm 762 * mount options. thus we can safely put this sb on the list and deal 763 * with it later 764 */ 765 if (!ss_initialized) { 766 spin_lock(&sb_security_lock); 767 if (list_empty(&newsbsec->list)) 768 list_add(&newsbsec->list, &superblock_security_head); 769 spin_unlock(&sb_security_lock); 770 return; 771 } 772 773 /* how can we clone if the old one wasn't set up?? */ 774 BUG_ON(!oldsbsec->initialized); 775 776 /* if fs is reusing a sb, just let its options stand... */ 777 if (newsbsec->initialized) 778 return; 779 780 mutex_lock(&newsbsec->lock); 781 782 newsbsec->flags = oldsbsec->flags; 783 784 newsbsec->sid = oldsbsec->sid; 785 newsbsec->def_sid = oldsbsec->def_sid; 786 newsbsec->behavior = oldsbsec->behavior; 787 788 if (set_context) { 789 u32 sid = oldsbsec->mntpoint_sid; 790 791 if (!set_fscontext) 792 newsbsec->sid = sid; 793 if (!set_rootcontext) { 794 struct inode *newinode = newsb->s_root->d_inode; 795 struct inode_security_struct *newisec = newinode->i_security; 796 newisec->sid = sid; 797 } 798 newsbsec->mntpoint_sid = sid; 799 } 800 if (set_rootcontext) { 801 const struct inode *oldinode = oldsb->s_root->d_inode; 802 const struct inode_security_struct *oldisec = oldinode->i_security; 803 struct inode *newinode = newsb->s_root->d_inode; 804 struct inode_security_struct *newisec = newinode->i_security; 805 806 newisec->sid = oldisec->sid; 807 } 808 809 sb_finish_set_opts(newsb); 810 mutex_unlock(&newsbsec->lock); 811 } 812 813 static int selinux_parse_opts_str(char *options, 814 struct security_mnt_opts *opts) 815 { 816 char *p; 817 char *context = NULL, *defcontext = NULL; 818 char *fscontext = NULL, *rootcontext = NULL; 819 int rc, num_mnt_opts = 0; 820 821 opts->num_mnt_opts = 0; 822 823 /* Standard string-based options. */ 824 while ((p = strsep(&options, "|")) != NULL) { 825 int token; 826 substring_t args[MAX_OPT_ARGS]; 827 828 if (!*p) 829 continue; 830 831 token = match_token(p, tokens, args); 832 833 switch (token) { 834 case Opt_context: 835 if (context || defcontext) { 836 rc = -EINVAL; 837 printk(KERN_WARNING SEL_MOUNT_FAIL_MSG); 838 goto out_err; 839 } 840 context = match_strdup(&args[0]); 841 if (!context) { 842 rc = -ENOMEM; 843 goto out_err; 844 } 845 break; 846 847 case Opt_fscontext: 848 if (fscontext) { 849 rc = -EINVAL; 850 printk(KERN_WARNING SEL_MOUNT_FAIL_MSG); 851 goto out_err; 852 } 853 fscontext = match_strdup(&args[0]); 854 if (!fscontext) { 855 rc = -ENOMEM; 856 goto out_err; 857 } 858 break; 859 860 case Opt_rootcontext: 861 if (rootcontext) { 862 rc = -EINVAL; 863 printk(KERN_WARNING SEL_MOUNT_FAIL_MSG); 864 goto out_err; 865 } 866 rootcontext = match_strdup(&args[0]); 867 if (!rootcontext) { 868 rc = -ENOMEM; 869 goto out_err; 870 } 871 break; 872 873 case Opt_defcontext: 874 if (context || defcontext) { 875 rc = -EINVAL; 876 printk(KERN_WARNING SEL_MOUNT_FAIL_MSG); 877 goto out_err; 878 } 879 defcontext = match_strdup(&args[0]); 880 if (!defcontext) { 881 rc = -ENOMEM; 882 goto out_err; 883 } 884 break; 885 886 default: 887 rc = -EINVAL; 888 printk(KERN_WARNING "SELinux: unknown mount option\n"); 889 goto out_err; 890 891 } 892 } 893 894 rc = -ENOMEM; 895 opts->mnt_opts = kcalloc(NUM_SEL_MNT_OPTS, sizeof(char *), GFP_ATOMIC); 896 if (!opts->mnt_opts) 897 goto out_err; 898 899 opts->mnt_opts_flags = kcalloc(NUM_SEL_MNT_OPTS, sizeof(int), GFP_ATOMIC); 900 if (!opts->mnt_opts_flags) { 901 kfree(opts->mnt_opts); 902 goto out_err; 903 } 904 905 if (fscontext) { 906 opts->mnt_opts[num_mnt_opts] = fscontext; 907 opts->mnt_opts_flags[num_mnt_opts++] = FSCONTEXT_MNT; 908 } 909 if (context) { 910 opts->mnt_opts[num_mnt_opts] = context; 911 opts->mnt_opts_flags[num_mnt_opts++] = CONTEXT_MNT; 912 } 913 if (rootcontext) { 914 opts->mnt_opts[num_mnt_opts] = rootcontext; 915 opts->mnt_opts_flags[num_mnt_opts++] = ROOTCONTEXT_MNT; 916 } 917 if (defcontext) { 918 opts->mnt_opts[num_mnt_opts] = defcontext; 919 opts->mnt_opts_flags[num_mnt_opts++] = DEFCONTEXT_MNT; 920 } 921 922 opts->num_mnt_opts = num_mnt_opts; 923 return 0; 924 925 out_err: 926 kfree(context); 927 kfree(defcontext); 928 kfree(fscontext); 929 kfree(rootcontext); 930 return rc; 931 } 932 /* 933 * string mount options parsing and call set the sbsec 934 */ 935 static int superblock_doinit(struct super_block *sb, void *data) 936 { 937 int rc = 0; 938 char *options = data; 939 struct security_mnt_opts opts; 940 941 security_init_mnt_opts(&opts); 942 943 if (!data) 944 goto out; 945 946 BUG_ON(sb->s_type->fs_flags & FS_BINARY_MOUNTDATA); 947 948 rc = selinux_parse_opts_str(options, &opts); 949 if (rc) 950 goto out_err; 951 952 out: 953 rc = selinux_set_mnt_opts(sb, &opts); 954 955 out_err: 956 security_free_mnt_opts(&opts); 957 return rc; 958 } 959 960 static void selinux_write_opts(struct seq_file *m, 961 struct security_mnt_opts *opts) 962 { 963 int i; 964 char *prefix; 965 966 for (i = 0; i < opts->num_mnt_opts; i++) { 967 char *has_comma = strchr(opts->mnt_opts[i], ','); 968 969 switch (opts->mnt_opts_flags[i]) { 970 case CONTEXT_MNT: 971 prefix = CONTEXT_STR; 972 break; 973 case FSCONTEXT_MNT: 974 prefix = FSCONTEXT_STR; 975 break; 976 case ROOTCONTEXT_MNT: 977 prefix = ROOTCONTEXT_STR; 978 break; 979 case DEFCONTEXT_MNT: 980 prefix = DEFCONTEXT_STR; 981 break; 982 default: 983 BUG(); 984 }; 985 /* we need a comma before each option */ 986 seq_putc(m, ','); 987 seq_puts(m, prefix); 988 if (has_comma) 989 seq_putc(m, '\"'); 990 seq_puts(m, opts->mnt_opts[i]); 991 if (has_comma) 992 seq_putc(m, '\"'); 993 } 994 } 995 996 static int selinux_sb_show_options(struct seq_file *m, struct super_block *sb) 997 { 998 struct security_mnt_opts opts; 999 int rc; 1000 1001 rc = selinux_get_mnt_opts(sb, &opts); 1002 if (rc) { 1003 /* before policy load we may get EINVAL, don't show anything */ 1004 if (rc == -EINVAL) 1005 rc = 0; 1006 return rc; 1007 } 1008 1009 selinux_write_opts(m, &opts); 1010 1011 security_free_mnt_opts(&opts); 1012 1013 return rc; 1014 } 1015 1016 static inline u16 inode_mode_to_security_class(umode_t mode) 1017 { 1018 switch (mode & S_IFMT) { 1019 case S_IFSOCK: 1020 return SECCLASS_SOCK_FILE; 1021 case S_IFLNK: 1022 return SECCLASS_LNK_FILE; 1023 case S_IFREG: 1024 return SECCLASS_FILE; 1025 case S_IFBLK: 1026 return SECCLASS_BLK_FILE; 1027 case S_IFDIR: 1028 return SECCLASS_DIR; 1029 case S_IFCHR: 1030 return SECCLASS_CHR_FILE; 1031 case S_IFIFO: 1032 return SECCLASS_FIFO_FILE; 1033 1034 } 1035 1036 return SECCLASS_FILE; 1037 } 1038 1039 static inline int default_protocol_stream(int protocol) 1040 { 1041 return (protocol == IPPROTO_IP || protocol == IPPROTO_TCP); 1042 } 1043 1044 static inline int default_protocol_dgram(int protocol) 1045 { 1046 return (protocol == IPPROTO_IP || protocol == IPPROTO_UDP); 1047 } 1048 1049 static inline u16 socket_type_to_security_class(int family, int type, int protocol) 1050 { 1051 switch (family) { 1052 case PF_UNIX: 1053 switch (type) { 1054 case SOCK_STREAM: 1055 case SOCK_SEQPACKET: 1056 return SECCLASS_UNIX_STREAM_SOCKET; 1057 case SOCK_DGRAM: 1058 return SECCLASS_UNIX_DGRAM_SOCKET; 1059 } 1060 break; 1061 case PF_INET: 1062 case PF_INET6: 1063 switch (type) { 1064 case SOCK_STREAM: 1065 if (default_protocol_stream(protocol)) 1066 return SECCLASS_TCP_SOCKET; 1067 else 1068 return SECCLASS_RAWIP_SOCKET; 1069 case SOCK_DGRAM: 1070 if (default_protocol_dgram(protocol)) 1071 return SECCLASS_UDP_SOCKET; 1072 else 1073 return SECCLASS_RAWIP_SOCKET; 1074 case SOCK_DCCP: 1075 return SECCLASS_DCCP_SOCKET; 1076 default: 1077 return SECCLASS_RAWIP_SOCKET; 1078 } 1079 break; 1080 case PF_NETLINK: 1081 switch (protocol) { 1082 case NETLINK_ROUTE: 1083 return SECCLASS_NETLINK_ROUTE_SOCKET; 1084 case NETLINK_FIREWALL: 1085 return SECCLASS_NETLINK_FIREWALL_SOCKET; 1086 case NETLINK_INET_DIAG: 1087 return SECCLASS_NETLINK_TCPDIAG_SOCKET; 1088 case NETLINK_NFLOG: 1089 return SECCLASS_NETLINK_NFLOG_SOCKET; 1090 case NETLINK_XFRM: 1091 return SECCLASS_NETLINK_XFRM_SOCKET; 1092 case NETLINK_SELINUX: 1093 return SECCLASS_NETLINK_SELINUX_SOCKET; 1094 case NETLINK_AUDIT: 1095 return SECCLASS_NETLINK_AUDIT_SOCKET; 1096 case NETLINK_IP6_FW: 1097 return SECCLASS_NETLINK_IP6FW_SOCKET; 1098 case NETLINK_DNRTMSG: 1099 return SECCLASS_NETLINK_DNRT_SOCKET; 1100 case NETLINK_KOBJECT_UEVENT: 1101 return SECCLASS_NETLINK_KOBJECT_UEVENT_SOCKET; 1102 default: 1103 return SECCLASS_NETLINK_SOCKET; 1104 } 1105 case PF_PACKET: 1106 return SECCLASS_PACKET_SOCKET; 1107 case PF_KEY: 1108 return SECCLASS_KEY_SOCKET; 1109 case PF_APPLETALK: 1110 return SECCLASS_APPLETALK_SOCKET; 1111 } 1112 1113 return SECCLASS_SOCKET; 1114 } 1115 1116 #ifdef CONFIG_PROC_FS 1117 static int selinux_proc_get_sid(struct proc_dir_entry *de, 1118 u16 tclass, 1119 u32 *sid) 1120 { 1121 int buflen, rc; 1122 char *buffer, *path, *end; 1123 1124 buffer = (char *)__get_free_page(GFP_KERNEL); 1125 if (!buffer) 1126 return -ENOMEM; 1127 1128 buflen = PAGE_SIZE; 1129 end = buffer+buflen; 1130 *--end = '\0'; 1131 buflen--; 1132 path = end-1; 1133 *path = '/'; 1134 while (de && de != de->parent) { 1135 buflen -= de->namelen + 1; 1136 if (buflen < 0) 1137 break; 1138 end -= de->namelen; 1139 memcpy(end, de->name, de->namelen); 1140 *--end = '/'; 1141 path = end; 1142 de = de->parent; 1143 } 1144 rc = security_genfs_sid("proc", path, tclass, sid); 1145 free_page((unsigned long)buffer); 1146 return rc; 1147 } 1148 #else 1149 static int selinux_proc_get_sid(struct proc_dir_entry *de, 1150 u16 tclass, 1151 u32 *sid) 1152 { 1153 return -EINVAL; 1154 } 1155 #endif 1156 1157 /* The inode's security attributes must be initialized before first use. */ 1158 static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dentry) 1159 { 1160 struct superblock_security_struct *sbsec = NULL; 1161 struct inode_security_struct *isec = inode->i_security; 1162 u32 sid; 1163 struct dentry *dentry; 1164 #define INITCONTEXTLEN 255 1165 char *context = NULL; 1166 unsigned len = 0; 1167 int rc = 0; 1168 1169 if (isec->initialized) 1170 goto out; 1171 1172 mutex_lock(&isec->lock); 1173 if (isec->initialized) 1174 goto out_unlock; 1175 1176 sbsec = inode->i_sb->s_security; 1177 if (!sbsec->initialized) { 1178 /* Defer initialization until selinux_complete_init, 1179 after the initial policy is loaded and the security 1180 server is ready to handle calls. */ 1181 spin_lock(&sbsec->isec_lock); 1182 if (list_empty(&isec->list)) 1183 list_add(&isec->list, &sbsec->isec_head); 1184 spin_unlock(&sbsec->isec_lock); 1185 goto out_unlock; 1186 } 1187 1188 switch (sbsec->behavior) { 1189 case SECURITY_FS_USE_XATTR: 1190 if (!inode->i_op->getxattr) { 1191 isec->sid = sbsec->def_sid; 1192 break; 1193 } 1194 1195 /* Need a dentry, since the xattr API requires one. 1196 Life would be simpler if we could just pass the inode. */ 1197 if (opt_dentry) { 1198 /* Called from d_instantiate or d_splice_alias. */ 1199 dentry = dget(opt_dentry); 1200 } else { 1201 /* Called from selinux_complete_init, try to find a dentry. */ 1202 dentry = d_find_alias(inode); 1203 } 1204 if (!dentry) { 1205 printk(KERN_WARNING "SELinux: %s: no dentry for dev=%s " 1206 "ino=%ld\n", __func__, inode->i_sb->s_id, 1207 inode->i_ino); 1208 goto out_unlock; 1209 } 1210 1211 len = INITCONTEXTLEN; 1212 context = kmalloc(len, GFP_NOFS); 1213 if (!context) { 1214 rc = -ENOMEM; 1215 dput(dentry); 1216 goto out_unlock; 1217 } 1218 rc = inode->i_op->getxattr(dentry, XATTR_NAME_SELINUX, 1219 context, len); 1220 if (rc == -ERANGE) { 1221 /* Need a larger buffer. Query for the right size. */ 1222 rc = inode->i_op->getxattr(dentry, XATTR_NAME_SELINUX, 1223 NULL, 0); 1224 if (rc < 0) { 1225 dput(dentry); 1226 goto out_unlock; 1227 } 1228 kfree(context); 1229 len = rc; 1230 context = kmalloc(len, GFP_NOFS); 1231 if (!context) { 1232 rc = -ENOMEM; 1233 dput(dentry); 1234 goto out_unlock; 1235 } 1236 rc = inode->i_op->getxattr(dentry, 1237 XATTR_NAME_SELINUX, 1238 context, len); 1239 } 1240 dput(dentry); 1241 if (rc < 0) { 1242 if (rc != -ENODATA) { 1243 printk(KERN_WARNING "SELinux: %s: getxattr returned " 1244 "%d for dev=%s ino=%ld\n", __func__, 1245 -rc, inode->i_sb->s_id, inode->i_ino); 1246 kfree(context); 1247 goto out_unlock; 1248 } 1249 /* Map ENODATA to the default file SID */ 1250 sid = sbsec->def_sid; 1251 rc = 0; 1252 } else { 1253 rc = security_context_to_sid_default(context, rc, &sid, 1254 sbsec->def_sid, 1255 GFP_NOFS); 1256 if (rc) { 1257 printk(KERN_WARNING "SELinux: %s: context_to_sid(%s) " 1258 "returned %d for dev=%s ino=%ld\n", 1259 __func__, context, -rc, 1260 inode->i_sb->s_id, inode->i_ino); 1261 kfree(context); 1262 /* Leave with the unlabeled SID */ 1263 rc = 0; 1264 break; 1265 } 1266 } 1267 kfree(context); 1268 isec->sid = sid; 1269 break; 1270 case SECURITY_FS_USE_TASK: 1271 isec->sid = isec->task_sid; 1272 break; 1273 case SECURITY_FS_USE_TRANS: 1274 /* Default to the fs SID. */ 1275 isec->sid = sbsec->sid; 1276 1277 /* Try to obtain a transition SID. */ 1278 isec->sclass = inode_mode_to_security_class(inode->i_mode); 1279 rc = security_transition_sid(isec->task_sid, 1280 sbsec->sid, 1281 isec->sclass, 1282 &sid); 1283 if (rc) 1284 goto out_unlock; 1285 isec->sid = sid; 1286 break; 1287 case SECURITY_FS_USE_MNTPOINT: 1288 isec->sid = sbsec->mntpoint_sid; 1289 break; 1290 default: 1291 /* Default to the fs superblock SID. */ 1292 isec->sid = sbsec->sid; 1293 1294 if (sbsec->proc && !S_ISLNK(inode->i_mode)) { 1295 struct proc_inode *proci = PROC_I(inode); 1296 if (proci->pde) { 1297 isec->sclass = inode_mode_to_security_class(inode->i_mode); 1298 rc = selinux_proc_get_sid(proci->pde, 1299 isec->sclass, 1300 &sid); 1301 if (rc) 1302 goto out_unlock; 1303 isec->sid = sid; 1304 } 1305 } 1306 break; 1307 } 1308 1309 isec->initialized = 1; 1310 1311 out_unlock: 1312 mutex_unlock(&isec->lock); 1313 out: 1314 if (isec->sclass == SECCLASS_FILE) 1315 isec->sclass = inode_mode_to_security_class(inode->i_mode); 1316 return rc; 1317 } 1318 1319 /* Convert a Linux signal to an access vector. */ 1320 static inline u32 signal_to_av(int sig) 1321 { 1322 u32 perm = 0; 1323 1324 switch (sig) { 1325 case SIGCHLD: 1326 /* Commonly granted from child to parent. */ 1327 perm = PROCESS__SIGCHLD; 1328 break; 1329 case SIGKILL: 1330 /* Cannot be caught or ignored */ 1331 perm = PROCESS__SIGKILL; 1332 break; 1333 case SIGSTOP: 1334 /* Cannot be caught or ignored */ 1335 perm = PROCESS__SIGSTOP; 1336 break; 1337 default: 1338 /* All other signals. */ 1339 perm = PROCESS__SIGNAL; 1340 break; 1341 } 1342 1343 return perm; 1344 } 1345 1346 /* Check permission betweeen a pair of tasks, e.g. signal checks, 1347 fork check, ptrace check, etc. */ 1348 static int task_has_perm(struct task_struct *tsk1, 1349 struct task_struct *tsk2, 1350 u32 perms) 1351 { 1352 struct task_security_struct *tsec1, *tsec2; 1353 1354 tsec1 = tsk1->security; 1355 tsec2 = tsk2->security; 1356 return avc_has_perm(tsec1->sid, tsec2->sid, 1357 SECCLASS_PROCESS, perms, NULL); 1358 } 1359 1360 #if CAP_LAST_CAP > 63 1361 #error Fix SELinux to handle capabilities > 63. 1362 #endif 1363 1364 /* Check whether a task is allowed to use a capability. */ 1365 static int task_has_capability(struct task_struct *tsk, 1366 int cap) 1367 { 1368 struct task_security_struct *tsec; 1369 struct avc_audit_data ad; 1370 u16 sclass; 1371 u32 av = CAP_TO_MASK(cap); 1372 1373 tsec = tsk->security; 1374 1375 AVC_AUDIT_DATA_INIT(&ad, CAP); 1376 ad.tsk = tsk; 1377 ad.u.cap = cap; 1378 1379 switch (CAP_TO_INDEX(cap)) { 1380 case 0: 1381 sclass = SECCLASS_CAPABILITY; 1382 break; 1383 case 1: 1384 sclass = SECCLASS_CAPABILITY2; 1385 break; 1386 default: 1387 printk(KERN_ERR 1388 "SELinux: out of range capability %d\n", cap); 1389 BUG(); 1390 } 1391 return avc_has_perm(tsec->sid, tsec->sid, sclass, av, &ad); 1392 } 1393 1394 /* Check whether a task is allowed to use a system operation. */ 1395 static int task_has_system(struct task_struct *tsk, 1396 u32 perms) 1397 { 1398 struct task_security_struct *tsec; 1399 1400 tsec = tsk->security; 1401 1402 return avc_has_perm(tsec->sid, SECINITSID_KERNEL, 1403 SECCLASS_SYSTEM, perms, NULL); 1404 } 1405 1406 /* Check whether a task has a particular permission to an inode. 1407 The 'adp' parameter is optional and allows other audit 1408 data to be passed (e.g. the dentry). */ 1409 static int inode_has_perm(struct task_struct *tsk, 1410 struct inode *inode, 1411 u32 perms, 1412 struct avc_audit_data *adp) 1413 { 1414 struct task_security_struct *tsec; 1415 struct inode_security_struct *isec; 1416 struct avc_audit_data ad; 1417 1418 if (unlikely(IS_PRIVATE(inode))) 1419 return 0; 1420 1421 tsec = tsk->security; 1422 isec = inode->i_security; 1423 1424 if (!adp) { 1425 adp = &ad; 1426 AVC_AUDIT_DATA_INIT(&ad, FS); 1427 ad.u.fs.inode = inode; 1428 } 1429 1430 return avc_has_perm(tsec->sid, isec->sid, isec->sclass, perms, adp); 1431 } 1432 1433 /* Same as inode_has_perm, but pass explicit audit data containing 1434 the dentry to help the auditing code to more easily generate the 1435 pathname if needed. */ 1436 static inline int dentry_has_perm(struct task_struct *tsk, 1437 struct vfsmount *mnt, 1438 struct dentry *dentry, 1439 u32 av) 1440 { 1441 struct inode *inode = dentry->d_inode; 1442 struct avc_audit_data ad; 1443 AVC_AUDIT_DATA_INIT(&ad, FS); 1444 ad.u.fs.path.mnt = mnt; 1445 ad.u.fs.path.dentry = dentry; 1446 return inode_has_perm(tsk, inode, av, &ad); 1447 } 1448 1449 /* Check whether a task can use an open file descriptor to 1450 access an inode in a given way. Check access to the 1451 descriptor itself, and then use dentry_has_perm to 1452 check a particular permission to the file. 1453 Access to the descriptor is implicitly granted if it 1454 has the same SID as the process. If av is zero, then 1455 access to the file is not checked, e.g. for cases 1456 where only the descriptor is affected like seek. */ 1457 static int file_has_perm(struct task_struct *tsk, 1458 struct file *file, 1459 u32 av) 1460 { 1461 struct task_security_struct *tsec = tsk->security; 1462 struct file_security_struct *fsec = file->f_security; 1463 struct inode *inode = file->f_path.dentry->d_inode; 1464 struct avc_audit_data ad; 1465 int rc; 1466 1467 AVC_AUDIT_DATA_INIT(&ad, FS); 1468 ad.u.fs.path = file->f_path; 1469 1470 if (tsec->sid != fsec->sid) { 1471 rc = avc_has_perm(tsec->sid, fsec->sid, 1472 SECCLASS_FD, 1473 FD__USE, 1474 &ad); 1475 if (rc) 1476 return rc; 1477 } 1478 1479 /* av is zero if only checking access to the descriptor. */ 1480 if (av) 1481 return inode_has_perm(tsk, inode, av, &ad); 1482 1483 return 0; 1484 } 1485 1486 /* Check whether a task can create a file. */ 1487 static int may_create(struct inode *dir, 1488 struct dentry *dentry, 1489 u16 tclass) 1490 { 1491 struct task_security_struct *tsec; 1492 struct inode_security_struct *dsec; 1493 struct superblock_security_struct *sbsec; 1494 u32 newsid; 1495 struct avc_audit_data ad; 1496 int rc; 1497 1498 tsec = current->security; 1499 dsec = dir->i_security; 1500 sbsec = dir->i_sb->s_security; 1501 1502 AVC_AUDIT_DATA_INIT(&ad, FS); 1503 ad.u.fs.path.dentry = dentry; 1504 1505 rc = avc_has_perm(tsec->sid, dsec->sid, SECCLASS_DIR, 1506 DIR__ADD_NAME | DIR__SEARCH, 1507 &ad); 1508 if (rc) 1509 return rc; 1510 1511 if (tsec->create_sid && sbsec->behavior != SECURITY_FS_USE_MNTPOINT) { 1512 newsid = tsec->create_sid; 1513 } else { 1514 rc = security_transition_sid(tsec->sid, dsec->sid, tclass, 1515 &newsid); 1516 if (rc) 1517 return rc; 1518 } 1519 1520 rc = avc_has_perm(tsec->sid, newsid, tclass, FILE__CREATE, &ad); 1521 if (rc) 1522 return rc; 1523 1524 return avc_has_perm(newsid, sbsec->sid, 1525 SECCLASS_FILESYSTEM, 1526 FILESYSTEM__ASSOCIATE, &ad); 1527 } 1528 1529 /* Check whether a task can create a key. */ 1530 static int may_create_key(u32 ksid, 1531 struct task_struct *ctx) 1532 { 1533 struct task_security_struct *tsec; 1534 1535 tsec = ctx->security; 1536 1537 return avc_has_perm(tsec->sid, ksid, SECCLASS_KEY, KEY__CREATE, NULL); 1538 } 1539 1540 #define MAY_LINK 0 1541 #define MAY_UNLINK 1 1542 #define MAY_RMDIR 2 1543 1544 /* Check whether a task can link, unlink, or rmdir a file/directory. */ 1545 static int may_link(struct inode *dir, 1546 struct dentry *dentry, 1547 int kind) 1548 1549 { 1550 struct task_security_struct *tsec; 1551 struct inode_security_struct *dsec, *isec; 1552 struct avc_audit_data ad; 1553 u32 av; 1554 int rc; 1555 1556 tsec = current->security; 1557 dsec = dir->i_security; 1558 isec = dentry->d_inode->i_security; 1559 1560 AVC_AUDIT_DATA_INIT(&ad, FS); 1561 ad.u.fs.path.dentry = dentry; 1562 1563 av = DIR__SEARCH; 1564 av |= (kind ? DIR__REMOVE_NAME : DIR__ADD_NAME); 1565 rc = avc_has_perm(tsec->sid, dsec->sid, SECCLASS_DIR, av, &ad); 1566 if (rc) 1567 return rc; 1568 1569 switch (kind) { 1570 case MAY_LINK: 1571 av = FILE__LINK; 1572 break; 1573 case MAY_UNLINK: 1574 av = FILE__UNLINK; 1575 break; 1576 case MAY_RMDIR: 1577 av = DIR__RMDIR; 1578 break; 1579 default: 1580 printk(KERN_WARNING "SELinux: %s: unrecognized kind %d\n", 1581 __func__, kind); 1582 return 0; 1583 } 1584 1585 rc = avc_has_perm(tsec->sid, isec->sid, isec->sclass, av, &ad); 1586 return rc; 1587 } 1588 1589 static inline int may_rename(struct inode *old_dir, 1590 struct dentry *old_dentry, 1591 struct inode *new_dir, 1592 struct dentry *new_dentry) 1593 { 1594 struct task_security_struct *tsec; 1595 struct inode_security_struct *old_dsec, *new_dsec, *old_isec, *new_isec; 1596 struct avc_audit_data ad; 1597 u32 av; 1598 int old_is_dir, new_is_dir; 1599 int rc; 1600 1601 tsec = current->security; 1602 old_dsec = old_dir->i_security; 1603 old_isec = old_dentry->d_inode->i_security; 1604 old_is_dir = S_ISDIR(old_dentry->d_inode->i_mode); 1605 new_dsec = new_dir->i_security; 1606 1607 AVC_AUDIT_DATA_INIT(&ad, FS); 1608 1609 ad.u.fs.path.dentry = old_dentry; 1610 rc = avc_has_perm(tsec->sid, old_dsec->sid, SECCLASS_DIR, 1611 DIR__REMOVE_NAME | DIR__SEARCH, &ad); 1612 if (rc) 1613 return rc; 1614 rc = avc_has_perm(tsec->sid, old_isec->sid, 1615 old_isec->sclass, FILE__RENAME, &ad); 1616 if (rc) 1617 return rc; 1618 if (old_is_dir && new_dir != old_dir) { 1619 rc = avc_has_perm(tsec->sid, old_isec->sid, 1620 old_isec->sclass, DIR__REPARENT, &ad); 1621 if (rc) 1622 return rc; 1623 } 1624 1625 ad.u.fs.path.dentry = new_dentry; 1626 av = DIR__ADD_NAME | DIR__SEARCH; 1627 if (new_dentry->d_inode) 1628 av |= DIR__REMOVE_NAME; 1629 rc = avc_has_perm(tsec->sid, new_dsec->sid, SECCLASS_DIR, av, &ad); 1630 if (rc) 1631 return rc; 1632 if (new_dentry->d_inode) { 1633 new_isec = new_dentry->d_inode->i_security; 1634 new_is_dir = S_ISDIR(new_dentry->d_inode->i_mode); 1635 rc = avc_has_perm(tsec->sid, new_isec->sid, 1636 new_isec->sclass, 1637 (new_is_dir ? DIR__RMDIR : FILE__UNLINK), &ad); 1638 if (rc) 1639 return rc; 1640 } 1641 1642 return 0; 1643 } 1644 1645 /* Check whether a task can perform a filesystem operation. */ 1646 static int superblock_has_perm(struct task_struct *tsk, 1647 struct super_block *sb, 1648 u32 perms, 1649 struct avc_audit_data *ad) 1650 { 1651 struct task_security_struct *tsec; 1652 struct superblock_security_struct *sbsec; 1653 1654 tsec = tsk->security; 1655 sbsec = sb->s_security; 1656 return avc_has_perm(tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM, 1657 perms, ad); 1658 } 1659 1660 /* Convert a Linux mode and permission mask to an access vector. */ 1661 static inline u32 file_mask_to_av(int mode, int mask) 1662 { 1663 u32 av = 0; 1664 1665 if ((mode & S_IFMT) != S_IFDIR) { 1666 if (mask & MAY_EXEC) 1667 av |= FILE__EXECUTE; 1668 if (mask & MAY_READ) 1669 av |= FILE__READ; 1670 1671 if (mask & MAY_APPEND) 1672 av |= FILE__APPEND; 1673 else if (mask & MAY_WRITE) 1674 av |= FILE__WRITE; 1675 1676 } else { 1677 if (mask & MAY_EXEC) 1678 av |= DIR__SEARCH; 1679 if (mask & MAY_WRITE) 1680 av |= DIR__WRITE; 1681 if (mask & MAY_READ) 1682 av |= DIR__READ; 1683 } 1684 1685 return av; 1686 } 1687 1688 /* 1689 * Convert a file mask to an access vector and include the correct open 1690 * open permission. 1691 */ 1692 static inline u32 open_file_mask_to_av(int mode, int mask) 1693 { 1694 u32 av = file_mask_to_av(mode, mask); 1695 1696 if (selinux_policycap_openperm) { 1697 /* 1698 * lnk files and socks do not really have an 'open' 1699 */ 1700 if (S_ISREG(mode)) 1701 av |= FILE__OPEN; 1702 else if (S_ISCHR(mode)) 1703 av |= CHR_FILE__OPEN; 1704 else if (S_ISBLK(mode)) 1705 av |= BLK_FILE__OPEN; 1706 else if (S_ISFIFO(mode)) 1707 av |= FIFO_FILE__OPEN; 1708 else if (S_ISDIR(mode)) 1709 av |= DIR__OPEN; 1710 else 1711 printk(KERN_ERR "SELinux: WARNING: inside %s with " 1712 "unknown mode:%x\n", __func__, mode); 1713 } 1714 return av; 1715 } 1716 1717 /* Convert a Linux file to an access vector. */ 1718 static inline u32 file_to_av(struct file *file) 1719 { 1720 u32 av = 0; 1721 1722 if (file->f_mode & FMODE_READ) 1723 av |= FILE__READ; 1724 if (file->f_mode & FMODE_WRITE) { 1725 if (file->f_flags & O_APPEND) 1726 av |= FILE__APPEND; 1727 else 1728 av |= FILE__WRITE; 1729 } 1730 if (!av) { 1731 /* 1732 * Special file opened with flags 3 for ioctl-only use. 1733 */ 1734 av = FILE__IOCTL; 1735 } 1736 1737 return av; 1738 } 1739 1740 /* Hook functions begin here. */ 1741 1742 static int selinux_ptrace_may_access(struct task_struct *child, 1743 unsigned int mode) 1744 { 1745 int rc; 1746 1747 rc = secondary_ops->ptrace_may_access(child, mode); 1748 if (rc) 1749 return rc; 1750 1751 if (mode == PTRACE_MODE_READ) { 1752 struct task_security_struct *tsec = current->security; 1753 struct task_security_struct *csec = child->security; 1754 return avc_has_perm(tsec->sid, csec->sid, 1755 SECCLASS_FILE, FILE__READ, NULL); 1756 } 1757 1758 return task_has_perm(current, child, PROCESS__PTRACE); 1759 } 1760 1761 static int selinux_ptrace_traceme(struct task_struct *parent) 1762 { 1763 int rc; 1764 1765 rc = secondary_ops->ptrace_traceme(parent); 1766 if (rc) 1767 return rc; 1768 1769 return task_has_perm(parent, current, PROCESS__PTRACE); 1770 } 1771 1772 static int selinux_capget(struct task_struct *target, kernel_cap_t *effective, 1773 kernel_cap_t *inheritable, kernel_cap_t *permitted) 1774 { 1775 int error; 1776 1777 error = task_has_perm(current, target, PROCESS__GETCAP); 1778 if (error) 1779 return error; 1780 1781 return secondary_ops->capget(target, effective, inheritable, permitted); 1782 } 1783 1784 static int selinux_capset_check(struct task_struct *target, kernel_cap_t *effective, 1785 kernel_cap_t *inheritable, kernel_cap_t *permitted) 1786 { 1787 int error; 1788 1789 error = secondary_ops->capset_check(target, effective, inheritable, permitted); 1790 if (error) 1791 return error; 1792 1793 return task_has_perm(current, target, PROCESS__SETCAP); 1794 } 1795 1796 static void selinux_capset_set(struct task_struct *target, kernel_cap_t *effective, 1797 kernel_cap_t *inheritable, kernel_cap_t *permitted) 1798 { 1799 secondary_ops->capset_set(target, effective, inheritable, permitted); 1800 } 1801 1802 static int selinux_capable(struct task_struct *tsk, int cap) 1803 { 1804 int rc; 1805 1806 rc = secondary_ops->capable(tsk, cap); 1807 if (rc) 1808 return rc; 1809 1810 return task_has_capability(tsk, cap); 1811 } 1812 1813 static int selinux_sysctl_get_sid(ctl_table *table, u16 tclass, u32 *sid) 1814 { 1815 int buflen, rc; 1816 char *buffer, *path, *end; 1817 1818 rc = -ENOMEM; 1819 buffer = (char *)__get_free_page(GFP_KERNEL); 1820 if (!buffer) 1821 goto out; 1822 1823 buflen = PAGE_SIZE; 1824 end = buffer+buflen; 1825 *--end = '\0'; 1826 buflen--; 1827 path = end-1; 1828 *path = '/'; 1829 while (table) { 1830 const char *name = table->procname; 1831 size_t namelen = strlen(name); 1832 buflen -= namelen + 1; 1833 if (buflen < 0) 1834 goto out_free; 1835 end -= namelen; 1836 memcpy(end, name, namelen); 1837 *--end = '/'; 1838 path = end; 1839 table = table->parent; 1840 } 1841 buflen -= 4; 1842 if (buflen < 0) 1843 goto out_free; 1844 end -= 4; 1845 memcpy(end, "/sys", 4); 1846 path = end; 1847 rc = security_genfs_sid("proc", path, tclass, sid); 1848 out_free: 1849 free_page((unsigned long)buffer); 1850 out: 1851 return rc; 1852 } 1853 1854 static int selinux_sysctl(ctl_table *table, int op) 1855 { 1856 int error = 0; 1857 u32 av; 1858 struct task_security_struct *tsec; 1859 u32 tsid; 1860 int rc; 1861 1862 rc = secondary_ops->sysctl(table, op); 1863 if (rc) 1864 return rc; 1865 1866 tsec = current->security; 1867 1868 rc = selinux_sysctl_get_sid(table, (op == 0001) ? 1869 SECCLASS_DIR : SECCLASS_FILE, &tsid); 1870 if (rc) { 1871 /* Default to the well-defined sysctl SID. */ 1872 tsid = SECINITSID_SYSCTL; 1873 } 1874 1875 /* The op values are "defined" in sysctl.c, thereby creating 1876 * a bad coupling between this module and sysctl.c */ 1877 if (op == 001) { 1878 error = avc_has_perm(tsec->sid, tsid, 1879 SECCLASS_DIR, DIR__SEARCH, NULL); 1880 } else { 1881 av = 0; 1882 if (op & 004) 1883 av |= FILE__READ; 1884 if (op & 002) 1885 av |= FILE__WRITE; 1886 if (av) 1887 error = avc_has_perm(tsec->sid, tsid, 1888 SECCLASS_FILE, av, NULL); 1889 } 1890 1891 return error; 1892 } 1893 1894 static int selinux_quotactl(int cmds, int type, int id, struct super_block *sb) 1895 { 1896 int rc = 0; 1897 1898 if (!sb) 1899 return 0; 1900 1901 switch (cmds) { 1902 case Q_SYNC: 1903 case Q_QUOTAON: 1904 case Q_QUOTAOFF: 1905 case Q_SETINFO: 1906 case Q_SETQUOTA: 1907 rc = superblock_has_perm(current, sb, FILESYSTEM__QUOTAMOD, 1908 NULL); 1909 break; 1910 case Q_GETFMT: 1911 case Q_GETINFO: 1912 case Q_GETQUOTA: 1913 rc = superblock_has_perm(current, sb, FILESYSTEM__QUOTAGET, 1914 NULL); 1915 break; 1916 default: 1917 rc = 0; /* let the kernel handle invalid cmds */ 1918 break; 1919 } 1920 return rc; 1921 } 1922 1923 static int selinux_quota_on(struct dentry *dentry) 1924 { 1925 return dentry_has_perm(current, NULL, dentry, FILE__QUOTAON); 1926 } 1927 1928 static int selinux_syslog(int type) 1929 { 1930 int rc; 1931 1932 rc = secondary_ops->syslog(type); 1933 if (rc) 1934 return rc; 1935 1936 switch (type) { 1937 case 3: /* Read last kernel messages */ 1938 case 10: /* Return size of the log buffer */ 1939 rc = task_has_system(current, SYSTEM__SYSLOG_READ); 1940 break; 1941 case 6: /* Disable logging to console */ 1942 case 7: /* Enable logging to console */ 1943 case 8: /* Set level of messages printed to console */ 1944 rc = task_has_system(current, SYSTEM__SYSLOG_CONSOLE); 1945 break; 1946 case 0: /* Close log */ 1947 case 1: /* Open log */ 1948 case 2: /* Read from log */ 1949 case 4: /* Read/clear last kernel messages */ 1950 case 5: /* Clear ring buffer */ 1951 default: 1952 rc = task_has_system(current, SYSTEM__SYSLOG_MOD); 1953 break; 1954 } 1955 return rc; 1956 } 1957 1958 /* 1959 * Check that a process has enough memory to allocate a new virtual 1960 * mapping. 0 means there is enough memory for the allocation to 1961 * succeed and -ENOMEM implies there is not. 1962 * 1963 * Note that secondary_ops->capable and task_has_perm_noaudit return 0 1964 * if the capability is granted, but __vm_enough_memory requires 1 if 1965 * the capability is granted. 1966 * 1967 * Do not audit the selinux permission check, as this is applied to all 1968 * processes that allocate mappings. 1969 */ 1970 static int selinux_vm_enough_memory(struct mm_struct *mm, long pages) 1971 { 1972 int rc, cap_sys_admin = 0; 1973 struct task_security_struct *tsec = current->security; 1974 1975 rc = secondary_ops->capable(current, CAP_SYS_ADMIN); 1976 if (rc == 0) 1977 rc = avc_has_perm_noaudit(tsec->sid, tsec->sid, 1978 SECCLASS_CAPABILITY, 1979 CAP_TO_MASK(CAP_SYS_ADMIN), 1980 0, 1981 NULL); 1982 1983 if (rc == 0) 1984 cap_sys_admin = 1; 1985 1986 return __vm_enough_memory(mm, pages, cap_sys_admin); 1987 } 1988 1989 /* binprm security operations */ 1990 1991 static int selinux_bprm_alloc_security(struct linux_binprm *bprm) 1992 { 1993 struct bprm_security_struct *bsec; 1994 1995 bsec = kzalloc(sizeof(struct bprm_security_struct), GFP_KERNEL); 1996 if (!bsec) 1997 return -ENOMEM; 1998 1999 bsec->sid = SECINITSID_UNLABELED; 2000 bsec->set = 0; 2001 2002 bprm->security = bsec; 2003 return 0; 2004 } 2005 2006 static int selinux_bprm_set_security(struct linux_binprm *bprm) 2007 { 2008 struct task_security_struct *tsec; 2009 struct inode *inode = bprm->file->f_path.dentry->d_inode; 2010 struct inode_security_struct *isec; 2011 struct bprm_security_struct *bsec; 2012 u32 newsid; 2013 struct avc_audit_data ad; 2014 int rc; 2015 2016 rc = secondary_ops->bprm_set_security(bprm); 2017 if (rc) 2018 return rc; 2019 2020 bsec = bprm->security; 2021 2022 if (bsec->set) 2023 return 0; 2024 2025 tsec = current->security; 2026 isec = inode->i_security; 2027 2028 /* Default to the current task SID. */ 2029 bsec->sid = tsec->sid; 2030 2031 /* Reset fs, key, and sock SIDs on execve. */ 2032 tsec->create_sid = 0; 2033 tsec->keycreate_sid = 0; 2034 tsec->sockcreate_sid = 0; 2035 2036 if (tsec->exec_sid) { 2037 newsid = tsec->exec_sid; 2038 /* Reset exec SID on execve. */ 2039 tsec->exec_sid = 0; 2040 } else { 2041 /* Check for a default transition on this program. */ 2042 rc = security_transition_sid(tsec->sid, isec->sid, 2043 SECCLASS_PROCESS, &newsid); 2044 if (rc) 2045 return rc; 2046 } 2047 2048 AVC_AUDIT_DATA_INIT(&ad, FS); 2049 ad.u.fs.path = bprm->file->f_path; 2050 2051 if (bprm->file->f_path.mnt->mnt_flags & MNT_NOSUID) 2052 newsid = tsec->sid; 2053 2054 if (tsec->sid == newsid) { 2055 rc = avc_has_perm(tsec->sid, isec->sid, 2056 SECCLASS_FILE, FILE__EXECUTE_NO_TRANS, &ad); 2057 if (rc) 2058 return rc; 2059 } else { 2060 /* Check permissions for the transition. */ 2061 rc = avc_has_perm(tsec->sid, newsid, 2062 SECCLASS_PROCESS, PROCESS__TRANSITION, &ad); 2063 if (rc) 2064 return rc; 2065 2066 rc = avc_has_perm(newsid, isec->sid, 2067 SECCLASS_FILE, FILE__ENTRYPOINT, &ad); 2068 if (rc) 2069 return rc; 2070 2071 /* Clear any possibly unsafe personality bits on exec: */ 2072 current->personality &= ~PER_CLEAR_ON_SETID; 2073 2074 /* Set the security field to the new SID. */ 2075 bsec->sid = newsid; 2076 } 2077 2078 bsec->set = 1; 2079 return 0; 2080 } 2081 2082 static int selinux_bprm_check_security(struct linux_binprm *bprm) 2083 { 2084 return secondary_ops->bprm_check_security(bprm); 2085 } 2086 2087 2088 static int selinux_bprm_secureexec(struct linux_binprm *bprm) 2089 { 2090 struct task_security_struct *tsec = current->security; 2091 int atsecure = 0; 2092 2093 if (tsec->osid != tsec->sid) { 2094 /* Enable secure mode for SIDs transitions unless 2095 the noatsecure permission is granted between 2096 the two SIDs, i.e. ahp returns 0. */ 2097 atsecure = avc_has_perm(tsec->osid, tsec->sid, 2098 SECCLASS_PROCESS, 2099 PROCESS__NOATSECURE, NULL); 2100 } 2101 2102 return (atsecure || secondary_ops->bprm_secureexec(bprm)); 2103 } 2104 2105 static void selinux_bprm_free_security(struct linux_binprm *bprm) 2106 { 2107 kfree(bprm->security); 2108 bprm->security = NULL; 2109 } 2110 2111 extern struct vfsmount *selinuxfs_mount; 2112 extern struct dentry *selinux_null; 2113 2114 /* Derived from fs/exec.c:flush_old_files. */ 2115 static inline void flush_unauthorized_files(struct files_struct *files) 2116 { 2117 struct avc_audit_data ad; 2118 struct file *file, *devnull = NULL; 2119 struct tty_struct *tty; 2120 struct fdtable *fdt; 2121 long j = -1; 2122 int drop_tty = 0; 2123 2124 mutex_lock(&tty_mutex); 2125 tty = get_current_tty(); 2126 if (tty) { 2127 file_list_lock(); 2128 file = list_entry(tty->tty_files.next, typeof(*file), f_u.fu_list); 2129 if (file) { 2130 /* Revalidate access to controlling tty. 2131 Use inode_has_perm on the tty inode directly rather 2132 than using file_has_perm, as this particular open 2133 file may belong to another process and we are only 2134 interested in the inode-based check here. */ 2135 struct inode *inode = file->f_path.dentry->d_inode; 2136 if (inode_has_perm(current, inode, 2137 FILE__READ | FILE__WRITE, NULL)) { 2138 drop_tty = 1; 2139 } 2140 } 2141 file_list_unlock(); 2142 } 2143 mutex_unlock(&tty_mutex); 2144 /* Reset controlling tty. */ 2145 if (drop_tty) 2146 no_tty(); 2147 2148 /* Revalidate access to inherited open files. */ 2149 2150 AVC_AUDIT_DATA_INIT(&ad, FS); 2151 2152 spin_lock(&files->file_lock); 2153 for (;;) { 2154 unsigned long set, i; 2155 int fd; 2156 2157 j++; 2158 i = j * __NFDBITS; 2159 fdt = files_fdtable(files); 2160 if (i >= fdt->max_fds) 2161 break; 2162 set = fdt->open_fds->fds_bits[j]; 2163 if (!set) 2164 continue; 2165 spin_unlock(&files->file_lock); 2166 for ( ; set ; i++, set >>= 1) { 2167 if (set & 1) { 2168 file = fget(i); 2169 if (!file) 2170 continue; 2171 if (file_has_perm(current, 2172 file, 2173 file_to_av(file))) { 2174 sys_close(i); 2175 fd = get_unused_fd(); 2176 if (fd != i) { 2177 if (fd >= 0) 2178 put_unused_fd(fd); 2179 fput(file); 2180 continue; 2181 } 2182 if (devnull) { 2183 get_file(devnull); 2184 } else { 2185 devnull = dentry_open(dget(selinux_null), mntget(selinuxfs_mount), O_RDWR); 2186 if (IS_ERR(devnull)) { 2187 devnull = NULL; 2188 put_unused_fd(fd); 2189 fput(file); 2190 continue; 2191 } 2192 } 2193 fd_install(fd, devnull); 2194 } 2195 fput(file); 2196 } 2197 } 2198 spin_lock(&files->file_lock); 2199 2200 } 2201 spin_unlock(&files->file_lock); 2202 } 2203 2204 static void selinux_bprm_apply_creds(struct linux_binprm *bprm, int unsafe) 2205 { 2206 struct task_security_struct *tsec; 2207 struct bprm_security_struct *bsec; 2208 u32 sid; 2209 int rc; 2210 2211 secondary_ops->bprm_apply_creds(bprm, unsafe); 2212 2213 tsec = current->security; 2214 2215 bsec = bprm->security; 2216 sid = bsec->sid; 2217 2218 tsec->osid = tsec->sid; 2219 bsec->unsafe = 0; 2220 if (tsec->sid != sid) { 2221 /* Check for shared state. If not ok, leave SID 2222 unchanged and kill. */ 2223 if (unsafe & LSM_UNSAFE_SHARE) { 2224 rc = avc_has_perm(tsec->sid, sid, SECCLASS_PROCESS, 2225 PROCESS__SHARE, NULL); 2226 if (rc) { 2227 bsec->unsafe = 1; 2228 return; 2229 } 2230 } 2231 2232 /* Check for ptracing, and update the task SID if ok. 2233 Otherwise, leave SID unchanged and kill. */ 2234 if (unsafe & (LSM_UNSAFE_PTRACE | LSM_UNSAFE_PTRACE_CAP)) { 2235 struct task_struct *tracer; 2236 struct task_security_struct *sec; 2237 u32 ptsid = 0; 2238 2239 rcu_read_lock(); 2240 tracer = tracehook_tracer_task(current); 2241 if (likely(tracer != NULL)) { 2242 sec = tracer->security; 2243 ptsid = sec->sid; 2244 } 2245 rcu_read_unlock(); 2246 2247 if (ptsid != 0) { 2248 rc = avc_has_perm(ptsid, sid, SECCLASS_PROCESS, 2249 PROCESS__PTRACE, NULL); 2250 if (rc) { 2251 bsec->unsafe = 1; 2252 return; 2253 } 2254 } 2255 } 2256 tsec->sid = sid; 2257 } 2258 } 2259 2260 /* 2261 * called after apply_creds without the task lock held 2262 */ 2263 static void selinux_bprm_post_apply_creds(struct linux_binprm *bprm) 2264 { 2265 struct task_security_struct *tsec; 2266 struct rlimit *rlim, *initrlim; 2267 struct itimerval itimer; 2268 struct bprm_security_struct *bsec; 2269 int rc, i; 2270 2271 tsec = current->security; 2272 bsec = bprm->security; 2273 2274 if (bsec->unsafe) { 2275 force_sig_specific(SIGKILL, current); 2276 return; 2277 } 2278 if (tsec->osid == tsec->sid) 2279 return; 2280 2281 /* Close files for which the new task SID is not authorized. */ 2282 flush_unauthorized_files(current->files); 2283 2284 /* Check whether the new SID can inherit signal state 2285 from the old SID. If not, clear itimers to avoid 2286 subsequent signal generation and flush and unblock 2287 signals. This must occur _after_ the task SID has 2288 been updated so that any kill done after the flush 2289 will be checked against the new SID. */ 2290 rc = avc_has_perm(tsec->osid, tsec->sid, SECCLASS_PROCESS, 2291 PROCESS__SIGINH, NULL); 2292 if (rc) { 2293 memset(&itimer, 0, sizeof itimer); 2294 for (i = 0; i < 3; i++) 2295 do_setitimer(i, &itimer, NULL); 2296 flush_signals(current); 2297 spin_lock_irq(¤t->sighand->siglock); 2298 flush_signal_handlers(current, 1); 2299 sigemptyset(¤t->blocked); 2300 recalc_sigpending(); 2301 spin_unlock_irq(¤t->sighand->siglock); 2302 } 2303 2304 /* Always clear parent death signal on SID transitions. */ 2305 current->pdeath_signal = 0; 2306 2307 /* Check whether the new SID can inherit resource limits 2308 from the old SID. If not, reset all soft limits to 2309 the lower of the current task's hard limit and the init 2310 task's soft limit. Note that the setting of hard limits 2311 (even to lower them) can be controlled by the setrlimit 2312 check. The inclusion of the init task's soft limit into 2313 the computation is to avoid resetting soft limits higher 2314 than the default soft limit for cases where the default 2315 is lower than the hard limit, e.g. RLIMIT_CORE or 2316 RLIMIT_STACK.*/ 2317 rc = avc_has_perm(tsec->osid, tsec->sid, SECCLASS_PROCESS, 2318 PROCESS__RLIMITINH, NULL); 2319 if (rc) { 2320 for (i = 0; i < RLIM_NLIMITS; i++) { 2321 rlim = current->signal->rlim + i; 2322 initrlim = init_task.signal->rlim+i; 2323 rlim->rlim_cur = min(rlim->rlim_max, initrlim->rlim_cur); 2324 } 2325 if (current->signal->rlim[RLIMIT_CPU].rlim_cur != RLIM_INFINITY) { 2326 /* 2327 * This will cause RLIMIT_CPU calculations 2328 * to be refigured. 2329 */ 2330 current->it_prof_expires = jiffies_to_cputime(1); 2331 } 2332 } 2333 2334 /* Wake up the parent if it is waiting so that it can 2335 recheck wait permission to the new task SID. */ 2336 wake_up_interruptible(¤t->parent->signal->wait_chldexit); 2337 } 2338 2339 /* superblock security operations */ 2340 2341 static int selinux_sb_alloc_security(struct super_block *sb) 2342 { 2343 return superblock_alloc_security(sb); 2344 } 2345 2346 static void selinux_sb_free_security(struct super_block *sb) 2347 { 2348 superblock_free_security(sb); 2349 } 2350 2351 static inline int match_prefix(char *prefix, int plen, char *option, int olen) 2352 { 2353 if (plen > olen) 2354 return 0; 2355 2356 return !memcmp(prefix, option, plen); 2357 } 2358 2359 static inline int selinux_option(char *option, int len) 2360 { 2361 return (match_prefix(CONTEXT_STR, sizeof(CONTEXT_STR)-1, option, len) || 2362 match_prefix(FSCONTEXT_STR, sizeof(FSCONTEXT_STR)-1, option, len) || 2363 match_prefix(DEFCONTEXT_STR, sizeof(DEFCONTEXT_STR)-1, option, len) || 2364 match_prefix(ROOTCONTEXT_STR, sizeof(ROOTCONTEXT_STR)-1, option, len)); 2365 } 2366 2367 static inline void take_option(char **to, char *from, int *first, int len) 2368 { 2369 if (!*first) { 2370 **to = ','; 2371 *to += 1; 2372 } else 2373 *first = 0; 2374 memcpy(*to, from, len); 2375 *to += len; 2376 } 2377 2378 static inline void take_selinux_option(char **to, char *from, int *first, 2379 int len) 2380 { 2381 int current_size = 0; 2382 2383 if (!*first) { 2384 **to = '|'; 2385 *to += 1; 2386 } else 2387 *first = 0; 2388 2389 while (current_size < len) { 2390 if (*from != '"') { 2391 **to = *from; 2392 *to += 1; 2393 } 2394 from += 1; 2395 current_size += 1; 2396 } 2397 } 2398 2399 static int selinux_sb_copy_data(char *orig, char *copy) 2400 { 2401 int fnosec, fsec, rc = 0; 2402 char *in_save, *in_curr, *in_end; 2403 char *sec_curr, *nosec_save, *nosec; 2404 int open_quote = 0; 2405 2406 in_curr = orig; 2407 sec_curr = copy; 2408 2409 nosec = (char *)get_zeroed_page(GFP_KERNEL); 2410 if (!nosec) { 2411 rc = -ENOMEM; 2412 goto out; 2413 } 2414 2415 nosec_save = nosec; 2416 fnosec = fsec = 1; 2417 in_save = in_end = orig; 2418 2419 do { 2420 if (*in_end == '"') 2421 open_quote = !open_quote; 2422 if ((*in_end == ',' && open_quote == 0) || 2423 *in_end == '\0') { 2424 int len = in_end - in_curr; 2425 2426 if (selinux_option(in_curr, len)) 2427 take_selinux_option(&sec_curr, in_curr, &fsec, len); 2428 else 2429 take_option(&nosec, in_curr, &fnosec, len); 2430 2431 in_curr = in_end + 1; 2432 } 2433 } while (*in_end++); 2434 2435 strcpy(in_save, nosec_save); 2436 free_page((unsigned long)nosec_save); 2437 out: 2438 return rc; 2439 } 2440 2441 static int selinux_sb_kern_mount(struct super_block *sb, void *data) 2442 { 2443 struct avc_audit_data ad; 2444 int rc; 2445 2446 rc = superblock_doinit(sb, data); 2447 if (rc) 2448 return rc; 2449 2450 AVC_AUDIT_DATA_INIT(&ad, FS); 2451 ad.u.fs.path.dentry = sb->s_root; 2452 return superblock_has_perm(current, sb, FILESYSTEM__MOUNT, &ad); 2453 } 2454 2455 static int selinux_sb_statfs(struct dentry *dentry) 2456 { 2457 struct avc_audit_data ad; 2458 2459 AVC_AUDIT_DATA_INIT(&ad, FS); 2460 ad.u.fs.path.dentry = dentry->d_sb->s_root; 2461 return superblock_has_perm(current, dentry->d_sb, FILESYSTEM__GETATTR, &ad); 2462 } 2463 2464 static int selinux_mount(char *dev_name, 2465 struct path *path, 2466 char *type, 2467 unsigned long flags, 2468 void *data) 2469 { 2470 int rc; 2471 2472 rc = secondary_ops->sb_mount(dev_name, path, type, flags, data); 2473 if (rc) 2474 return rc; 2475 2476 if (flags & MS_REMOUNT) 2477 return superblock_has_perm(current, path->mnt->mnt_sb, 2478 FILESYSTEM__REMOUNT, NULL); 2479 else 2480 return dentry_has_perm(current, path->mnt, path->dentry, 2481 FILE__MOUNTON); 2482 } 2483 2484 static int selinux_umount(struct vfsmount *mnt, int flags) 2485 { 2486 int rc; 2487 2488 rc = secondary_ops->sb_umount(mnt, flags); 2489 if (rc) 2490 return rc; 2491 2492 return superblock_has_perm(current, mnt->mnt_sb, 2493 FILESYSTEM__UNMOUNT, NULL); 2494 } 2495 2496 /* inode security operations */ 2497 2498 static int selinux_inode_alloc_security(struct inode *inode) 2499 { 2500 return inode_alloc_security(inode); 2501 } 2502 2503 static void selinux_inode_free_security(struct inode *inode) 2504 { 2505 inode_free_security(inode); 2506 } 2507 2508 static int selinux_inode_init_security(struct inode *inode, struct inode *dir, 2509 char **name, void **value, 2510 size_t *len) 2511 { 2512 struct task_security_struct *tsec; 2513 struct inode_security_struct *dsec; 2514 struct superblock_security_struct *sbsec; 2515 u32 newsid, clen; 2516 int rc; 2517 char *namep = NULL, *context; 2518 2519 tsec = current->security; 2520 dsec = dir->i_security; 2521 sbsec = dir->i_sb->s_security; 2522 2523 if (tsec->create_sid && sbsec->behavior != SECURITY_FS_USE_MNTPOINT) { 2524 newsid = tsec->create_sid; 2525 } else { 2526 rc = security_transition_sid(tsec->sid, dsec->sid, 2527 inode_mode_to_security_class(inode->i_mode), 2528 &newsid); 2529 if (rc) { 2530 printk(KERN_WARNING "%s: " 2531 "security_transition_sid failed, rc=%d (dev=%s " 2532 "ino=%ld)\n", 2533 __func__, 2534 -rc, inode->i_sb->s_id, inode->i_ino); 2535 return rc; 2536 } 2537 } 2538 2539 /* Possibly defer initialization to selinux_complete_init. */ 2540 if (sbsec->initialized) { 2541 struct inode_security_struct *isec = inode->i_security; 2542 isec->sclass = inode_mode_to_security_class(inode->i_mode); 2543 isec->sid = newsid; 2544 isec->initialized = 1; 2545 } 2546 2547 if (!ss_initialized || sbsec->behavior == SECURITY_FS_USE_MNTPOINT) 2548 return -EOPNOTSUPP; 2549 2550 if (name) { 2551 namep = kstrdup(XATTR_SELINUX_SUFFIX, GFP_NOFS); 2552 if (!namep) 2553 return -ENOMEM; 2554 *name = namep; 2555 } 2556 2557 if (value && len) { 2558 rc = security_sid_to_context_force(newsid, &context, &clen); 2559 if (rc) { 2560 kfree(namep); 2561 return rc; 2562 } 2563 *value = context; 2564 *len = clen; 2565 } 2566 2567 return 0; 2568 } 2569 2570 static int selinux_inode_create(struct inode *dir, struct dentry *dentry, int mask) 2571 { 2572 return may_create(dir, dentry, SECCLASS_FILE); 2573 } 2574 2575 static int selinux_inode_link(struct dentry *old_dentry, struct inode *dir, struct dentry *new_dentry) 2576 { 2577 int rc; 2578 2579 rc = secondary_ops->inode_link(old_dentry, dir, new_dentry); 2580 if (rc) 2581 return rc; 2582 return may_link(dir, old_dentry, MAY_LINK); 2583 } 2584 2585 static int selinux_inode_unlink(struct inode *dir, struct dentry *dentry) 2586 { 2587 int rc; 2588 2589 rc = secondary_ops->inode_unlink(dir, dentry); 2590 if (rc) 2591 return rc; 2592 return may_link(dir, dentry, MAY_UNLINK); 2593 } 2594 2595 static int selinux_inode_symlink(struct inode *dir, struct dentry *dentry, const char *name) 2596 { 2597 return may_create(dir, dentry, SECCLASS_LNK_FILE); 2598 } 2599 2600 static int selinux_inode_mkdir(struct inode *dir, struct dentry *dentry, int mask) 2601 { 2602 return may_create(dir, dentry, SECCLASS_DIR); 2603 } 2604 2605 static int selinux_inode_rmdir(struct inode *dir, struct dentry *dentry) 2606 { 2607 return may_link(dir, dentry, MAY_RMDIR); 2608 } 2609 2610 static int selinux_inode_mknod(struct inode *dir, struct dentry *dentry, int mode, dev_t dev) 2611 { 2612 int rc; 2613 2614 rc = secondary_ops->inode_mknod(dir, dentry, mode, dev); 2615 if (rc) 2616 return rc; 2617 2618 return may_create(dir, dentry, inode_mode_to_security_class(mode)); 2619 } 2620 2621 static int selinux_inode_rename(struct inode *old_inode, struct dentry *old_dentry, 2622 struct inode *new_inode, struct dentry *new_dentry) 2623 { 2624 return may_rename(old_inode, old_dentry, new_inode, new_dentry); 2625 } 2626 2627 static int selinux_inode_readlink(struct dentry *dentry) 2628 { 2629 return dentry_has_perm(current, NULL, dentry, FILE__READ); 2630 } 2631 2632 static int selinux_inode_follow_link(struct dentry *dentry, struct nameidata *nameidata) 2633 { 2634 int rc; 2635 2636 rc = secondary_ops->inode_follow_link(dentry, nameidata); 2637 if (rc) 2638 return rc; 2639 return dentry_has_perm(current, NULL, dentry, FILE__READ); 2640 } 2641 2642 static int selinux_inode_permission(struct inode *inode, int mask) 2643 { 2644 int rc; 2645 2646 rc = secondary_ops->inode_permission(inode, mask); 2647 if (rc) 2648 return rc; 2649 2650 if (!mask) { 2651 /* No permission to check. Existence test. */ 2652 return 0; 2653 } 2654 2655 return inode_has_perm(current, inode, 2656 open_file_mask_to_av(inode->i_mode, mask), NULL); 2657 } 2658 2659 static int selinux_inode_setattr(struct dentry *dentry, struct iattr *iattr) 2660 { 2661 int rc; 2662 2663 rc = secondary_ops->inode_setattr(dentry, iattr); 2664 if (rc) 2665 return rc; 2666 2667 if (iattr->ia_valid & ATTR_FORCE) 2668 return 0; 2669 2670 if (iattr->ia_valid & (ATTR_MODE | ATTR_UID | ATTR_GID | 2671 ATTR_ATIME_SET | ATTR_MTIME_SET)) 2672 return dentry_has_perm(current, NULL, dentry, FILE__SETATTR); 2673 2674 return dentry_has_perm(current, NULL, dentry, FILE__WRITE); 2675 } 2676 2677 static int selinux_inode_getattr(struct vfsmount *mnt, struct dentry *dentry) 2678 { 2679 return dentry_has_perm(current, mnt, dentry, FILE__GETATTR); 2680 } 2681 2682 static int selinux_inode_setotherxattr(struct dentry *dentry, const char *name) 2683 { 2684 if (!strncmp(name, XATTR_SECURITY_PREFIX, 2685 sizeof XATTR_SECURITY_PREFIX - 1)) { 2686 if (!strcmp(name, XATTR_NAME_CAPS)) { 2687 if (!capable(CAP_SETFCAP)) 2688 return -EPERM; 2689 } else if (!capable(CAP_SYS_ADMIN)) { 2690 /* A different attribute in the security namespace. 2691 Restrict to administrator. */ 2692 return -EPERM; 2693 } 2694 } 2695 2696 /* Not an attribute we recognize, so just check the 2697 ordinary setattr permission. */ 2698 return dentry_has_perm(current, NULL, dentry, FILE__SETATTR); 2699 } 2700 2701 static int selinux_inode_setxattr(struct dentry *dentry, const char *name, 2702 const void *value, size_t size, int flags) 2703 { 2704 struct task_security_struct *tsec = current->security; 2705 struct inode *inode = dentry->d_inode; 2706 struct inode_security_struct *isec = inode->i_security; 2707 struct superblock_security_struct *sbsec; 2708 struct avc_audit_data ad; 2709 u32 newsid; 2710 int rc = 0; 2711 2712 if (strcmp(name, XATTR_NAME_SELINUX)) 2713 return selinux_inode_setotherxattr(dentry, name); 2714 2715 sbsec = inode->i_sb->s_security; 2716 if (sbsec->behavior == SECURITY_FS_USE_MNTPOINT) 2717 return -EOPNOTSUPP; 2718 2719 if (!is_owner_or_cap(inode)) 2720 return -EPERM; 2721 2722 AVC_AUDIT_DATA_INIT(&ad, FS); 2723 ad.u.fs.path.dentry = dentry; 2724 2725 rc = avc_has_perm(tsec->sid, isec->sid, isec->sclass, 2726 FILE__RELABELFROM, &ad); 2727 if (rc) 2728 return rc; 2729 2730 rc = security_context_to_sid(value, size, &newsid); 2731 if (rc == -EINVAL) { 2732 if (!capable(CAP_MAC_ADMIN)) 2733 return rc; 2734 rc = security_context_to_sid_force(value, size, &newsid); 2735 } 2736 if (rc) 2737 return rc; 2738 2739 rc = avc_has_perm(tsec->sid, newsid, isec->sclass, 2740 FILE__RELABELTO, &ad); 2741 if (rc) 2742 return rc; 2743 2744 rc = security_validate_transition(isec->sid, newsid, tsec->sid, 2745 isec->sclass); 2746 if (rc) 2747 return rc; 2748 2749 return avc_has_perm(newsid, 2750 sbsec->sid, 2751 SECCLASS_FILESYSTEM, 2752 FILESYSTEM__ASSOCIATE, 2753 &ad); 2754 } 2755 2756 static void selinux_inode_post_setxattr(struct dentry *dentry, const char *name, 2757 const void *value, size_t size, 2758 int flags) 2759 { 2760 struct inode *inode = dentry->d_inode; 2761 struct inode_security_struct *isec = inode->i_security; 2762 u32 newsid; 2763 int rc; 2764 2765 if (strcmp(name, XATTR_NAME_SELINUX)) { 2766 /* Not an attribute we recognize, so nothing to do. */ 2767 return; 2768 } 2769 2770 rc = security_context_to_sid_force(value, size, &newsid); 2771 if (rc) { 2772 printk(KERN_ERR "SELinux: unable to map context to SID" 2773 "for (%s, %lu), rc=%d\n", 2774 inode->i_sb->s_id, inode->i_ino, -rc); 2775 return; 2776 } 2777 2778 isec->sid = newsid; 2779 return; 2780 } 2781 2782 static int selinux_inode_getxattr(struct dentry *dentry, const char *name) 2783 { 2784 return dentry_has_perm(current, NULL, dentry, FILE__GETATTR); 2785 } 2786 2787 static int selinux_inode_listxattr(struct dentry *dentry) 2788 { 2789 return dentry_has_perm(current, NULL, dentry, FILE__GETATTR); 2790 } 2791 2792 static int selinux_inode_removexattr(struct dentry *dentry, const char *name) 2793 { 2794 if (strcmp(name, XATTR_NAME_SELINUX)) 2795 return selinux_inode_setotherxattr(dentry, name); 2796 2797 /* No one is allowed to remove a SELinux security label. 2798 You can change the label, but all data must be labeled. */ 2799 return -EACCES; 2800 } 2801 2802 /* 2803 * Copy the inode security context value to the user. 2804 * 2805 * Permission check is handled by selinux_inode_getxattr hook. 2806 */ 2807 static int selinux_inode_getsecurity(const struct inode *inode, const char *name, void **buffer, bool alloc) 2808 { 2809 u32 size; 2810 int error; 2811 char *context = NULL; 2812 struct task_security_struct *tsec = current->security; 2813 struct inode_security_struct *isec = inode->i_security; 2814 2815 if (strcmp(name, XATTR_SELINUX_SUFFIX)) 2816 return -EOPNOTSUPP; 2817 2818 /* 2819 * If the caller has CAP_MAC_ADMIN, then get the raw context 2820 * value even if it is not defined by current policy; otherwise, 2821 * use the in-core value under current policy. 2822 * Use the non-auditing forms of the permission checks since 2823 * getxattr may be called by unprivileged processes commonly 2824 * and lack of permission just means that we fall back to the 2825 * in-core context value, not a denial. 2826 */ 2827 error = secondary_ops->capable(current, CAP_MAC_ADMIN); 2828 if (!error) 2829 error = avc_has_perm_noaudit(tsec->sid, tsec->sid, 2830 SECCLASS_CAPABILITY2, 2831 CAPABILITY2__MAC_ADMIN, 2832 0, 2833 NULL); 2834 if (!error) 2835 error = security_sid_to_context_force(isec->sid, &context, 2836 &size); 2837 else 2838 error = security_sid_to_context(isec->sid, &context, &size); 2839 if (error) 2840 return error; 2841 error = size; 2842 if (alloc) { 2843 *buffer = context; 2844 goto out_nofree; 2845 } 2846 kfree(context); 2847 out_nofree: 2848 return error; 2849 } 2850 2851 static int selinux_inode_setsecurity(struct inode *inode, const char *name, 2852 const void *value, size_t size, int flags) 2853 { 2854 struct inode_security_struct *isec = inode->i_security; 2855 u32 newsid; 2856 int rc; 2857 2858 if (strcmp(name, XATTR_SELINUX_SUFFIX)) 2859 return -EOPNOTSUPP; 2860 2861 if (!value || !size) 2862 return -EACCES; 2863 2864 rc = security_context_to_sid((void *)value, size, &newsid); 2865 if (rc) 2866 return rc; 2867 2868 isec->sid = newsid; 2869 return 0; 2870 } 2871 2872 static int selinux_inode_listsecurity(struct inode *inode, char *buffer, size_t buffer_size) 2873 { 2874 const int len = sizeof(XATTR_NAME_SELINUX); 2875 if (buffer && len <= buffer_size) 2876 memcpy(buffer, XATTR_NAME_SELINUX, len); 2877 return len; 2878 } 2879 2880 static int selinux_inode_need_killpriv(struct dentry *dentry) 2881 { 2882 return secondary_ops->inode_need_killpriv(dentry); 2883 } 2884 2885 static int selinux_inode_killpriv(struct dentry *dentry) 2886 { 2887 return secondary_ops->inode_killpriv(dentry); 2888 } 2889 2890 static void selinux_inode_getsecid(const struct inode *inode, u32 *secid) 2891 { 2892 struct inode_security_struct *isec = inode->i_security; 2893 *secid = isec->sid; 2894 } 2895 2896 /* file security operations */ 2897 2898 static int selinux_revalidate_file_permission(struct file *file, int mask) 2899 { 2900 int rc; 2901 struct inode *inode = file->f_path.dentry->d_inode; 2902 2903 if (!mask) { 2904 /* No permission to check. Existence test. */ 2905 return 0; 2906 } 2907 2908 /* file_mask_to_av won't add FILE__WRITE if MAY_APPEND is set */ 2909 if ((file->f_flags & O_APPEND) && (mask & MAY_WRITE)) 2910 mask |= MAY_APPEND; 2911 2912 rc = file_has_perm(current, file, 2913 file_mask_to_av(inode->i_mode, mask)); 2914 if (rc) 2915 return rc; 2916 2917 return selinux_netlbl_inode_permission(inode, mask); 2918 } 2919 2920 static int selinux_file_permission(struct file *file, int mask) 2921 { 2922 struct inode *inode = file->f_path.dentry->d_inode; 2923 struct task_security_struct *tsec = current->security; 2924 struct file_security_struct *fsec = file->f_security; 2925 struct inode_security_struct *isec = inode->i_security; 2926 2927 if (!mask) { 2928 /* No permission to check. Existence test. */ 2929 return 0; 2930 } 2931 2932 if (tsec->sid == fsec->sid && fsec->isid == isec->sid 2933 && fsec->pseqno == avc_policy_seqno()) 2934 return selinux_netlbl_inode_permission(inode, mask); 2935 2936 return selinux_revalidate_file_permission(file, mask); 2937 } 2938 2939 static int selinux_file_alloc_security(struct file *file) 2940 { 2941 return file_alloc_security(file); 2942 } 2943 2944 static void selinux_file_free_security(struct file *file) 2945 { 2946 file_free_security(file); 2947 } 2948 2949 static int selinux_file_ioctl(struct file *file, unsigned int cmd, 2950 unsigned long arg) 2951 { 2952 u32 av = 0; 2953 2954 if (_IOC_DIR(cmd) & _IOC_WRITE) 2955 av |= FILE__WRITE; 2956 if (_IOC_DIR(cmd) & _IOC_READ) 2957 av |= FILE__READ; 2958 if (!av) 2959 av = FILE__IOCTL; 2960 2961 return file_has_perm(current, file, av); 2962 } 2963 2964 static int file_map_prot_check(struct file *file, unsigned long prot, int shared) 2965 { 2966 #ifndef CONFIG_PPC32 2967 if ((prot & PROT_EXEC) && (!file || (!shared && (prot & PROT_WRITE)))) { 2968 /* 2969 * We are making executable an anonymous mapping or a 2970 * private file mapping that will also be writable. 2971 * This has an additional check. 2972 */ 2973 int rc = task_has_perm(current, current, PROCESS__EXECMEM); 2974 if (rc) 2975 return rc; 2976 } 2977 #endif 2978 2979 if (file) { 2980 /* read access is always possible with a mapping */ 2981 u32 av = FILE__READ; 2982 2983 /* write access only matters if the mapping is shared */ 2984 if (shared && (prot & PROT_WRITE)) 2985 av |= FILE__WRITE; 2986 2987 if (prot & PROT_EXEC) 2988 av |= FILE__EXECUTE; 2989 2990 return file_has_perm(current, file, av); 2991 } 2992 return 0; 2993 } 2994 2995 static int selinux_file_mmap(struct file *file, unsigned long reqprot, 2996 unsigned long prot, unsigned long flags, 2997 unsigned long addr, unsigned long addr_only) 2998 { 2999 int rc = 0; 3000 u32 sid = ((struct task_security_struct *)(current->security))->sid; 3001 3002 if (addr < mmap_min_addr) 3003 rc = avc_has_perm(sid, sid, SECCLASS_MEMPROTECT, 3004 MEMPROTECT__MMAP_ZERO, NULL); 3005 if (rc || addr_only) 3006 return rc; 3007 3008 if (selinux_checkreqprot) 3009 prot = reqprot; 3010 3011 return file_map_prot_check(file, prot, 3012 (flags & MAP_TYPE) == MAP_SHARED); 3013 } 3014 3015 static int selinux_file_mprotect(struct vm_area_struct *vma, 3016 unsigned long reqprot, 3017 unsigned long prot) 3018 { 3019 int rc; 3020 3021 rc = secondary_ops->file_mprotect(vma, reqprot, prot); 3022 if (rc) 3023 return rc; 3024 3025 if (selinux_checkreqprot) 3026 prot = reqprot; 3027 3028 #ifndef CONFIG_PPC32 3029 if ((prot & PROT_EXEC) && !(vma->vm_flags & VM_EXEC)) { 3030 rc = 0; 3031 if (vma->vm_start >= vma->vm_mm->start_brk && 3032 vma->vm_end <= vma->vm_mm->brk) { 3033 rc = task_has_perm(current, current, 3034 PROCESS__EXECHEAP); 3035 } else if (!vma->vm_file && 3036 vma->vm_start <= vma->vm_mm->start_stack && 3037 vma->vm_end >= vma->vm_mm->start_stack) { 3038 rc = task_has_perm(current, current, PROCESS__EXECSTACK); 3039 } else if (vma->vm_file && vma->anon_vma) { 3040 /* 3041 * We are making executable a file mapping that has 3042 * had some COW done. Since pages might have been 3043 * written, check ability to execute the possibly 3044 * modified content. This typically should only 3045 * occur for text relocations. 3046 */ 3047 rc = file_has_perm(current, vma->vm_file, 3048 FILE__EXECMOD); 3049 } 3050 if (rc) 3051 return rc; 3052 } 3053 #endif 3054 3055 return file_map_prot_check(vma->vm_file, prot, vma->vm_flags&VM_SHARED); 3056 } 3057 3058 static int selinux_file_lock(struct file *file, unsigned int cmd) 3059 { 3060 return file_has_perm(current, file, FILE__LOCK); 3061 } 3062 3063 static int selinux_file_fcntl(struct file *file, unsigned int cmd, 3064 unsigned long arg) 3065 { 3066 int err = 0; 3067 3068 switch (cmd) { 3069 case F_SETFL: 3070 if (!file->f_path.dentry || !file->f_path.dentry->d_inode) { 3071 err = -EINVAL; 3072 break; 3073 } 3074 3075 if ((file->f_flags & O_APPEND) && !(arg & O_APPEND)) { 3076 err = file_has_perm(current, file, FILE__WRITE); 3077 break; 3078 } 3079 /* fall through */ 3080 case F_SETOWN: 3081 case F_SETSIG: 3082 case F_GETFL: 3083 case F_GETOWN: 3084 case F_GETSIG: 3085 /* Just check FD__USE permission */ 3086 err = file_has_perm(current, file, 0); 3087 break; 3088 case F_GETLK: 3089 case F_SETLK: 3090 case F_SETLKW: 3091 #if BITS_PER_LONG == 32 3092 case F_GETLK64: 3093 case F_SETLK64: 3094 case F_SETLKW64: 3095 #endif 3096 if (!file->f_path.dentry || !file->f_path.dentry->d_inode) { 3097 err = -EINVAL; 3098 break; 3099 } 3100 err = file_has_perm(current, file, FILE__LOCK); 3101 break; 3102 } 3103 3104 return err; 3105 } 3106 3107 static int selinux_file_set_fowner(struct file *file) 3108 { 3109 struct task_security_struct *tsec; 3110 struct file_security_struct *fsec; 3111 3112 tsec = current->security; 3113 fsec = file->f_security; 3114 fsec->fown_sid = tsec->sid; 3115 3116 return 0; 3117 } 3118 3119 static int selinux_file_send_sigiotask(struct task_struct *tsk, 3120 struct fown_struct *fown, int signum) 3121 { 3122 struct file *file; 3123 u32 perm; 3124 struct task_security_struct *tsec; 3125 struct file_security_struct *fsec; 3126 3127 /* struct fown_struct is never outside the context of a struct file */ 3128 file = container_of(fown, struct file, f_owner); 3129 3130 tsec = tsk->security; 3131 fsec = file->f_security; 3132 3133 if (!signum) 3134 perm = signal_to_av(SIGIO); /* as per send_sigio_to_task */ 3135 else 3136 perm = signal_to_av(signum); 3137 3138 return avc_has_perm(fsec->fown_sid, tsec->sid, 3139 SECCLASS_PROCESS, perm, NULL); 3140 } 3141 3142 static int selinux_file_receive(struct file *file) 3143 { 3144 return file_has_perm(current, file, file_to_av(file)); 3145 } 3146 3147 static int selinux_dentry_open(struct file *file) 3148 { 3149 struct file_security_struct *fsec; 3150 struct inode *inode; 3151 struct inode_security_struct *isec; 3152 inode = file->f_path.dentry->d_inode; 3153 fsec = file->f_security; 3154 isec = inode->i_security; 3155 /* 3156 * Save inode label and policy sequence number 3157 * at open-time so that selinux_file_permission 3158 * can determine whether revalidation is necessary. 3159 * Task label is already saved in the file security 3160 * struct as its SID. 3161 */ 3162 fsec->isid = isec->sid; 3163 fsec->pseqno = avc_policy_seqno(); 3164 /* 3165 * Since the inode label or policy seqno may have changed 3166 * between the selinux_inode_permission check and the saving 3167 * of state above, recheck that access is still permitted. 3168 * Otherwise, access might never be revalidated against the 3169 * new inode label or new policy. 3170 * This check is not redundant - do not remove. 3171 */ 3172 return inode_has_perm(current, inode, file_to_av(file), NULL); 3173 } 3174 3175 /* task security operations */ 3176 3177 static int selinux_task_create(unsigned long clone_flags) 3178 { 3179 int rc; 3180 3181 rc = secondary_ops->task_create(clone_flags); 3182 if (rc) 3183 return rc; 3184 3185 return task_has_perm(current, current, PROCESS__FORK); 3186 } 3187 3188 static int selinux_task_alloc_security(struct task_struct *tsk) 3189 { 3190 struct task_security_struct *tsec1, *tsec2; 3191 int rc; 3192 3193 tsec1 = current->security; 3194 3195 rc = task_alloc_security(tsk); 3196 if (rc) 3197 return rc; 3198 tsec2 = tsk->security; 3199 3200 tsec2->osid = tsec1->osid; 3201 tsec2->sid = tsec1->sid; 3202 3203 /* Retain the exec, fs, key, and sock SIDs across fork */ 3204 tsec2->exec_sid = tsec1->exec_sid; 3205 tsec2->create_sid = tsec1->create_sid; 3206 tsec2->keycreate_sid = tsec1->keycreate_sid; 3207 tsec2->sockcreate_sid = tsec1->sockcreate_sid; 3208 3209 return 0; 3210 } 3211 3212 static void selinux_task_free_security(struct task_struct *tsk) 3213 { 3214 task_free_security(tsk); 3215 } 3216 3217 static int selinux_task_setuid(uid_t id0, uid_t id1, uid_t id2, int flags) 3218 { 3219 /* Since setuid only affects the current process, and 3220 since the SELinux controls are not based on the Linux 3221 identity attributes, SELinux does not need to control 3222 this operation. However, SELinux does control the use 3223 of the CAP_SETUID and CAP_SETGID capabilities using the 3224 capable hook. */ 3225 return 0; 3226 } 3227 3228 static int selinux_task_post_setuid(uid_t id0, uid_t id1, uid_t id2, int flags) 3229 { 3230 return secondary_ops->task_post_setuid(id0, id1, id2, flags); 3231 } 3232 3233 static int selinux_task_setgid(gid_t id0, gid_t id1, gid_t id2, int flags) 3234 { 3235 /* See the comment for setuid above. */ 3236 return 0; 3237 } 3238 3239 static int selinux_task_setpgid(struct task_struct *p, pid_t pgid) 3240 { 3241 return task_has_perm(current, p, PROCESS__SETPGID); 3242 } 3243 3244 static int selinux_task_getpgid(struct task_struct *p) 3245 { 3246 return task_has_perm(current, p, PROCESS__GETPGID); 3247 } 3248 3249 static int selinux_task_getsid(struct task_struct *p) 3250 { 3251 return task_has_perm(current, p, PROCESS__GETSESSION); 3252 } 3253 3254 static void selinux_task_getsecid(struct task_struct *p, u32 *secid) 3255 { 3256 struct task_security_struct *tsec = p->security; 3257 *secid = tsec->sid; 3258 } 3259 3260 static int selinux_task_setgroups(struct group_info *group_info) 3261 { 3262 /* See the comment for setuid above. */ 3263 return 0; 3264 } 3265 3266 static int selinux_task_setnice(struct task_struct *p, int nice) 3267 { 3268 int rc; 3269 3270 rc = secondary_ops->task_setnice(p, nice); 3271 if (rc) 3272 return rc; 3273 3274 return task_has_perm(current, p, PROCESS__SETSCHED); 3275 } 3276 3277 static int selinux_task_setioprio(struct task_struct *p, int ioprio) 3278 { 3279 int rc; 3280 3281 rc = secondary_ops->task_setioprio(p, ioprio); 3282 if (rc) 3283 return rc; 3284 3285 return task_has_perm(current, p, PROCESS__SETSCHED); 3286 } 3287 3288 static int selinux_task_getioprio(struct task_struct *p) 3289 { 3290 return task_has_perm(current, p, PROCESS__GETSCHED); 3291 } 3292 3293 static int selinux_task_setrlimit(unsigned int resource, struct rlimit *new_rlim) 3294 { 3295 struct rlimit *old_rlim = current->signal->rlim + resource; 3296 int rc; 3297 3298 rc = secondary_ops->task_setrlimit(resource, new_rlim); 3299 if (rc) 3300 return rc; 3301 3302 /* Control the ability to change the hard limit (whether 3303 lowering or raising it), so that the hard limit can 3304 later be used as a safe reset point for the soft limit 3305 upon context transitions. See selinux_bprm_apply_creds. */ 3306 if (old_rlim->rlim_max != new_rlim->rlim_max) 3307 return task_has_perm(current, current, PROCESS__SETRLIMIT); 3308 3309 return 0; 3310 } 3311 3312 static int selinux_task_setscheduler(struct task_struct *p, int policy, struct sched_param *lp) 3313 { 3314 int rc; 3315 3316 rc = secondary_ops->task_setscheduler(p, policy, lp); 3317 if (rc) 3318 return rc; 3319 3320 return task_has_perm(current, p, PROCESS__SETSCHED); 3321 } 3322 3323 static int selinux_task_getscheduler(struct task_struct *p) 3324 { 3325 return task_has_perm(current, p, PROCESS__GETSCHED); 3326 } 3327 3328 static int selinux_task_movememory(struct task_struct *p) 3329 { 3330 return task_has_perm(current, p, PROCESS__SETSCHED); 3331 } 3332 3333 static int selinux_task_kill(struct task_struct *p, struct siginfo *info, 3334 int sig, u32 secid) 3335 { 3336 u32 perm; 3337 int rc; 3338 struct task_security_struct *tsec; 3339 3340 rc = secondary_ops->task_kill(p, info, sig, secid); 3341 if (rc) 3342 return rc; 3343 3344 if (!sig) 3345 perm = PROCESS__SIGNULL; /* null signal; existence test */ 3346 else 3347 perm = signal_to_av(sig); 3348 tsec = p->security; 3349 if (secid) 3350 rc = avc_has_perm(secid, tsec->sid, SECCLASS_PROCESS, perm, NULL); 3351 else 3352 rc = task_has_perm(current, p, perm); 3353 return rc; 3354 } 3355 3356 static int selinux_task_prctl(int option, 3357 unsigned long arg2, 3358 unsigned long arg3, 3359 unsigned long arg4, 3360 unsigned long arg5, 3361 long *rc_p) 3362 { 3363 /* The current prctl operations do not appear to require 3364 any SELinux controls since they merely observe or modify 3365 the state of the current process. */ 3366 return secondary_ops->task_prctl(option, arg2, arg3, arg4, arg5, rc_p); 3367 } 3368 3369 static int selinux_task_wait(struct task_struct *p) 3370 { 3371 return task_has_perm(p, current, PROCESS__SIGCHLD); 3372 } 3373 3374 static void selinux_task_reparent_to_init(struct task_struct *p) 3375 { 3376 struct task_security_struct *tsec; 3377 3378 secondary_ops->task_reparent_to_init(p); 3379 3380 tsec = p->security; 3381 tsec->osid = tsec->sid; 3382 tsec->sid = SECINITSID_KERNEL; 3383 return; 3384 } 3385 3386 static void selinux_task_to_inode(struct task_struct *p, 3387 struct inode *inode) 3388 { 3389 struct task_security_struct *tsec = p->security; 3390 struct inode_security_struct *isec = inode->i_security; 3391 3392 isec->sid = tsec->sid; 3393 isec->initialized = 1; 3394 return; 3395 } 3396 3397 /* Returns error only if unable to parse addresses */ 3398 static int selinux_parse_skb_ipv4(struct sk_buff *skb, 3399 struct avc_audit_data *ad, u8 *proto) 3400 { 3401 int offset, ihlen, ret = -EINVAL; 3402 struct iphdr _iph, *ih; 3403 3404 offset = skb_network_offset(skb); 3405 ih = skb_header_pointer(skb, offset, sizeof(_iph), &_iph); 3406 if (ih == NULL) 3407 goto out; 3408 3409 ihlen = ih->ihl * 4; 3410 if (ihlen < sizeof(_iph)) 3411 goto out; 3412 3413 ad->u.net.v4info.saddr = ih->saddr; 3414 ad->u.net.v4info.daddr = ih->daddr; 3415 ret = 0; 3416 3417 if (proto) 3418 *proto = ih->protocol; 3419 3420 switch (ih->protocol) { 3421 case IPPROTO_TCP: { 3422 struct tcphdr _tcph, *th; 3423 3424 if (ntohs(ih->frag_off) & IP_OFFSET) 3425 break; 3426 3427 offset += ihlen; 3428 th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph); 3429 if (th == NULL) 3430 break; 3431 3432 ad->u.net.sport = th->source; 3433 ad->u.net.dport = th->dest; 3434 break; 3435 } 3436 3437 case IPPROTO_UDP: { 3438 struct udphdr _udph, *uh; 3439 3440 if (ntohs(ih->frag_off) & IP_OFFSET) 3441 break; 3442 3443 offset += ihlen; 3444 uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph); 3445 if (uh == NULL) 3446 break; 3447 3448 ad->u.net.sport = uh->source; 3449 ad->u.net.dport = uh->dest; 3450 break; 3451 } 3452 3453 case IPPROTO_DCCP: { 3454 struct dccp_hdr _dccph, *dh; 3455 3456 if (ntohs(ih->frag_off) & IP_OFFSET) 3457 break; 3458 3459 offset += ihlen; 3460 dh = skb_header_pointer(skb, offset, sizeof(_dccph), &_dccph); 3461 if (dh == NULL) 3462 break; 3463 3464 ad->u.net.sport = dh->dccph_sport; 3465 ad->u.net.dport = dh->dccph_dport; 3466 break; 3467 } 3468 3469 default: 3470 break; 3471 } 3472 out: 3473 return ret; 3474 } 3475 3476 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE) 3477 3478 /* Returns error only if unable to parse addresses */ 3479 static int selinux_parse_skb_ipv6(struct sk_buff *skb, 3480 struct avc_audit_data *ad, u8 *proto) 3481 { 3482 u8 nexthdr; 3483 int ret = -EINVAL, offset; 3484 struct ipv6hdr _ipv6h, *ip6; 3485 3486 offset = skb_network_offset(skb); 3487 ip6 = skb_header_pointer(skb, offset, sizeof(_ipv6h), &_ipv6h); 3488 if (ip6 == NULL) 3489 goto out; 3490 3491 ipv6_addr_copy(&ad->u.net.v6info.saddr, &ip6->saddr); 3492 ipv6_addr_copy(&ad->u.net.v6info.daddr, &ip6->daddr); 3493 ret = 0; 3494 3495 nexthdr = ip6->nexthdr; 3496 offset += sizeof(_ipv6h); 3497 offset = ipv6_skip_exthdr(skb, offset, &nexthdr); 3498 if (offset < 0) 3499 goto out; 3500 3501 if (proto) 3502 *proto = nexthdr; 3503 3504 switch (nexthdr) { 3505 case IPPROTO_TCP: { 3506 struct tcphdr _tcph, *th; 3507 3508 th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph); 3509 if (th == NULL) 3510 break; 3511 3512 ad->u.net.sport = th->source; 3513 ad->u.net.dport = th->dest; 3514 break; 3515 } 3516 3517 case IPPROTO_UDP: { 3518 struct udphdr _udph, *uh; 3519 3520 uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph); 3521 if (uh == NULL) 3522 break; 3523 3524 ad->u.net.sport = uh->source; 3525 ad->u.net.dport = uh->dest; 3526 break; 3527 } 3528 3529 case IPPROTO_DCCP: { 3530 struct dccp_hdr _dccph, *dh; 3531 3532 dh = skb_header_pointer(skb, offset, sizeof(_dccph), &_dccph); 3533 if (dh == NULL) 3534 break; 3535 3536 ad->u.net.sport = dh->dccph_sport; 3537 ad->u.net.dport = dh->dccph_dport; 3538 break; 3539 } 3540 3541 /* includes fragments */ 3542 default: 3543 break; 3544 } 3545 out: 3546 return ret; 3547 } 3548 3549 #endif /* IPV6 */ 3550 3551 static int selinux_parse_skb(struct sk_buff *skb, struct avc_audit_data *ad, 3552 char **_addrp, int src, u8 *proto) 3553 { 3554 char *addrp; 3555 int ret; 3556 3557 switch (ad->u.net.family) { 3558 case PF_INET: 3559 ret = selinux_parse_skb_ipv4(skb, ad, proto); 3560 if (ret) 3561 goto parse_error; 3562 addrp = (char *)(src ? &ad->u.net.v4info.saddr : 3563 &ad->u.net.v4info.daddr); 3564 goto okay; 3565 3566 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE) 3567 case PF_INET6: 3568 ret = selinux_parse_skb_ipv6(skb, ad, proto); 3569 if (ret) 3570 goto parse_error; 3571 addrp = (char *)(src ? &ad->u.net.v6info.saddr : 3572 &ad->u.net.v6info.daddr); 3573 goto okay; 3574 #endif /* IPV6 */ 3575 default: 3576 addrp = NULL; 3577 goto okay; 3578 } 3579 3580 parse_error: 3581 printk(KERN_WARNING 3582 "SELinux: failure in selinux_parse_skb()," 3583 " unable to parse packet\n"); 3584 return ret; 3585 3586 okay: 3587 if (_addrp) 3588 *_addrp = addrp; 3589 return 0; 3590 } 3591 3592 /** 3593 * selinux_skb_peerlbl_sid - Determine the peer label of a packet 3594 * @skb: the packet 3595 * @family: protocol family 3596 * @sid: the packet's peer label SID 3597 * 3598 * Description: 3599 * Check the various different forms of network peer labeling and determine 3600 * the peer label/SID for the packet; most of the magic actually occurs in 3601 * the security server function security_net_peersid_cmp(). The function 3602 * returns zero if the value in @sid is valid (although it may be SECSID_NULL) 3603 * or -EACCES if @sid is invalid due to inconsistencies with the different 3604 * peer labels. 3605 * 3606 */ 3607 static int selinux_skb_peerlbl_sid(struct sk_buff *skb, u16 family, u32 *sid) 3608 { 3609 int err; 3610 u32 xfrm_sid; 3611 u32 nlbl_sid; 3612 u32 nlbl_type; 3613 3614 selinux_skb_xfrm_sid(skb, &xfrm_sid); 3615 selinux_netlbl_skbuff_getsid(skb, family, &nlbl_type, &nlbl_sid); 3616 3617 err = security_net_peersid_resolve(nlbl_sid, nlbl_type, xfrm_sid, sid); 3618 if (unlikely(err)) { 3619 printk(KERN_WARNING 3620 "SELinux: failure in selinux_skb_peerlbl_sid()," 3621 " unable to determine packet's peer label\n"); 3622 return -EACCES; 3623 } 3624 3625 return 0; 3626 } 3627 3628 /* socket security operations */ 3629 static int socket_has_perm(struct task_struct *task, struct socket *sock, 3630 u32 perms) 3631 { 3632 struct inode_security_struct *isec; 3633 struct task_security_struct *tsec; 3634 struct avc_audit_data ad; 3635 int err = 0; 3636 3637 tsec = task->security; 3638 isec = SOCK_INODE(sock)->i_security; 3639 3640 if (isec->sid == SECINITSID_KERNEL) 3641 goto out; 3642 3643 AVC_AUDIT_DATA_INIT(&ad, NET); 3644 ad.u.net.sk = sock->sk; 3645 err = avc_has_perm(tsec->sid, isec->sid, isec->sclass, perms, &ad); 3646 3647 out: 3648 return err; 3649 } 3650 3651 static int selinux_socket_create(int family, int type, 3652 int protocol, int kern) 3653 { 3654 int err = 0; 3655 struct task_security_struct *tsec; 3656 u32 newsid; 3657 3658 if (kern) 3659 goto out; 3660 3661 tsec = current->security; 3662 newsid = tsec->sockcreate_sid ? : tsec->sid; 3663 err = avc_has_perm(tsec->sid, newsid, 3664 socket_type_to_security_class(family, type, 3665 protocol), SOCKET__CREATE, NULL); 3666 3667 out: 3668 return err; 3669 } 3670 3671 static int selinux_socket_post_create(struct socket *sock, int family, 3672 int type, int protocol, int kern) 3673 { 3674 int err = 0; 3675 struct inode_security_struct *isec; 3676 struct task_security_struct *tsec; 3677 struct sk_security_struct *sksec; 3678 u32 newsid; 3679 3680 isec = SOCK_INODE(sock)->i_security; 3681 3682 tsec = current->security; 3683 newsid = tsec->sockcreate_sid ? : tsec->sid; 3684 isec->sclass = socket_type_to_security_class(family, type, protocol); 3685 isec->sid = kern ? SECINITSID_KERNEL : newsid; 3686 isec->initialized = 1; 3687 3688 if (sock->sk) { 3689 sksec = sock->sk->sk_security; 3690 sksec->sid = isec->sid; 3691 sksec->sclass = isec->sclass; 3692 err = selinux_netlbl_socket_post_create(sock); 3693 } 3694 3695 return err; 3696 } 3697 3698 /* Range of port numbers used to automatically bind. 3699 Need to determine whether we should perform a name_bind 3700 permission check between the socket and the port number. */ 3701 3702 static int selinux_socket_bind(struct socket *sock, struct sockaddr *address, int addrlen) 3703 { 3704 u16 family; 3705 int err; 3706 3707 err = socket_has_perm(current, sock, SOCKET__BIND); 3708 if (err) 3709 goto out; 3710 3711 /* 3712 * If PF_INET or PF_INET6, check name_bind permission for the port. 3713 * Multiple address binding for SCTP is not supported yet: we just 3714 * check the first address now. 3715 */ 3716 family = sock->sk->sk_family; 3717 if (family == PF_INET || family == PF_INET6) { 3718 char *addrp; 3719 struct inode_security_struct *isec; 3720 struct task_security_struct *tsec; 3721 struct avc_audit_data ad; 3722 struct sockaddr_in *addr4 = NULL; 3723 struct sockaddr_in6 *addr6 = NULL; 3724 unsigned short snum; 3725 struct sock *sk = sock->sk; 3726 u32 sid, node_perm; 3727 3728 tsec = current->security; 3729 isec = SOCK_INODE(sock)->i_security; 3730 3731 if (family == PF_INET) { 3732 addr4 = (struct sockaddr_in *)address; 3733 snum = ntohs(addr4->sin_port); 3734 addrp = (char *)&addr4->sin_addr.s_addr; 3735 } else { 3736 addr6 = (struct sockaddr_in6 *)address; 3737 snum = ntohs(addr6->sin6_port); 3738 addrp = (char *)&addr6->sin6_addr.s6_addr; 3739 } 3740 3741 if (snum) { 3742 int low, high; 3743 3744 inet_get_local_port_range(&low, &high); 3745 3746 if (snum < max(PROT_SOCK, low) || snum > high) { 3747 err = sel_netport_sid(sk->sk_protocol, 3748 snum, &sid); 3749 if (err) 3750 goto out; 3751 AVC_AUDIT_DATA_INIT(&ad, NET); 3752 ad.u.net.sport = htons(snum); 3753 ad.u.net.family = family; 3754 err = avc_has_perm(isec->sid, sid, 3755 isec->sclass, 3756 SOCKET__NAME_BIND, &ad); 3757 if (err) 3758 goto out; 3759 } 3760 } 3761 3762 switch (isec->sclass) { 3763 case SECCLASS_TCP_SOCKET: 3764 node_perm = TCP_SOCKET__NODE_BIND; 3765 break; 3766 3767 case SECCLASS_UDP_SOCKET: 3768 node_perm = UDP_SOCKET__NODE_BIND; 3769 break; 3770 3771 case SECCLASS_DCCP_SOCKET: 3772 node_perm = DCCP_SOCKET__NODE_BIND; 3773 break; 3774 3775 default: 3776 node_perm = RAWIP_SOCKET__NODE_BIND; 3777 break; 3778 } 3779 3780 err = sel_netnode_sid(addrp, family, &sid); 3781 if (err) 3782 goto out; 3783 3784 AVC_AUDIT_DATA_INIT(&ad, NET); 3785 ad.u.net.sport = htons(snum); 3786 ad.u.net.family = family; 3787 3788 if (family == PF_INET) 3789 ad.u.net.v4info.saddr = addr4->sin_addr.s_addr; 3790 else 3791 ipv6_addr_copy(&ad.u.net.v6info.saddr, &addr6->sin6_addr); 3792 3793 err = avc_has_perm(isec->sid, sid, 3794 isec->sclass, node_perm, &ad); 3795 if (err) 3796 goto out; 3797 } 3798 out: 3799 return err; 3800 } 3801 3802 static int selinux_socket_connect(struct socket *sock, struct sockaddr *address, int addrlen) 3803 { 3804 struct inode_security_struct *isec; 3805 int err; 3806 3807 err = socket_has_perm(current, sock, SOCKET__CONNECT); 3808 if (err) 3809 return err; 3810 3811 /* 3812 * If a TCP or DCCP socket, check name_connect permission for the port. 3813 */ 3814 isec = SOCK_INODE(sock)->i_security; 3815 if (isec->sclass == SECCLASS_TCP_SOCKET || 3816 isec->sclass == SECCLASS_DCCP_SOCKET) { 3817 struct sock *sk = sock->sk; 3818 struct avc_audit_data ad; 3819 struct sockaddr_in *addr4 = NULL; 3820 struct sockaddr_in6 *addr6 = NULL; 3821 unsigned short snum; 3822 u32 sid, perm; 3823 3824 if (sk->sk_family == PF_INET) { 3825 addr4 = (struct sockaddr_in *)address; 3826 if (addrlen < sizeof(struct sockaddr_in)) 3827 return -EINVAL; 3828 snum = ntohs(addr4->sin_port); 3829 } else { 3830 addr6 = (struct sockaddr_in6 *)address; 3831 if (addrlen < SIN6_LEN_RFC2133) 3832 return -EINVAL; 3833 snum = ntohs(addr6->sin6_port); 3834 } 3835 3836 err = sel_netport_sid(sk->sk_protocol, snum, &sid); 3837 if (err) 3838 goto out; 3839 3840 perm = (isec->sclass == SECCLASS_TCP_SOCKET) ? 3841 TCP_SOCKET__NAME_CONNECT : DCCP_SOCKET__NAME_CONNECT; 3842 3843 AVC_AUDIT_DATA_INIT(&ad, NET); 3844 ad.u.net.dport = htons(snum); 3845 ad.u.net.family = sk->sk_family; 3846 err = avc_has_perm(isec->sid, sid, isec->sclass, perm, &ad); 3847 if (err) 3848 goto out; 3849 } 3850 3851 out: 3852 return err; 3853 } 3854 3855 static int selinux_socket_listen(struct socket *sock, int backlog) 3856 { 3857 return socket_has_perm(current, sock, SOCKET__LISTEN); 3858 } 3859 3860 static int selinux_socket_accept(struct socket *sock, struct socket *newsock) 3861 { 3862 int err; 3863 struct inode_security_struct *isec; 3864 struct inode_security_struct *newisec; 3865 3866 err = socket_has_perm(current, sock, SOCKET__ACCEPT); 3867 if (err) 3868 return err; 3869 3870 newisec = SOCK_INODE(newsock)->i_security; 3871 3872 isec = SOCK_INODE(sock)->i_security; 3873 newisec->sclass = isec->sclass; 3874 newisec->sid = isec->sid; 3875 newisec->initialized = 1; 3876 3877 return 0; 3878 } 3879 3880 static int selinux_socket_sendmsg(struct socket *sock, struct msghdr *msg, 3881 int size) 3882 { 3883 int rc; 3884 3885 rc = socket_has_perm(current, sock, SOCKET__WRITE); 3886 if (rc) 3887 return rc; 3888 3889 return selinux_netlbl_inode_permission(SOCK_INODE(sock), MAY_WRITE); 3890 } 3891 3892 static int selinux_socket_recvmsg(struct socket *sock, struct msghdr *msg, 3893 int size, int flags) 3894 { 3895 return socket_has_perm(current, sock, SOCKET__READ); 3896 } 3897 3898 static int selinux_socket_getsockname(struct socket *sock) 3899 { 3900 return socket_has_perm(current, sock, SOCKET__GETATTR); 3901 } 3902 3903 static int selinux_socket_getpeername(struct socket *sock) 3904 { 3905 return socket_has_perm(current, sock, SOCKET__GETATTR); 3906 } 3907 3908 static int selinux_socket_setsockopt(struct socket *sock, int level, int optname) 3909 { 3910 int err; 3911 3912 err = socket_has_perm(current, sock, SOCKET__SETOPT); 3913 if (err) 3914 return err; 3915 3916 return selinux_netlbl_socket_setsockopt(sock, level, optname); 3917 } 3918 3919 static int selinux_socket_getsockopt(struct socket *sock, int level, 3920 int optname) 3921 { 3922 return socket_has_perm(current, sock, SOCKET__GETOPT); 3923 } 3924 3925 static int selinux_socket_shutdown(struct socket *sock, int how) 3926 { 3927 return socket_has_perm(current, sock, SOCKET__SHUTDOWN); 3928 } 3929 3930 static int selinux_socket_unix_stream_connect(struct socket *sock, 3931 struct socket *other, 3932 struct sock *newsk) 3933 { 3934 struct sk_security_struct *ssec; 3935 struct inode_security_struct *isec; 3936 struct inode_security_struct *other_isec; 3937 struct avc_audit_data ad; 3938 int err; 3939 3940 err = secondary_ops->unix_stream_connect(sock, other, newsk); 3941 if (err) 3942 return err; 3943 3944 isec = SOCK_INODE(sock)->i_security; 3945 other_isec = SOCK_INODE(other)->i_security; 3946 3947 AVC_AUDIT_DATA_INIT(&ad, NET); 3948 ad.u.net.sk = other->sk; 3949 3950 err = avc_has_perm(isec->sid, other_isec->sid, 3951 isec->sclass, 3952 UNIX_STREAM_SOCKET__CONNECTTO, &ad); 3953 if (err) 3954 return err; 3955 3956 /* connecting socket */ 3957 ssec = sock->sk->sk_security; 3958 ssec->peer_sid = other_isec->sid; 3959 3960 /* server child socket */ 3961 ssec = newsk->sk_security; 3962 ssec->peer_sid = isec->sid; 3963 err = security_sid_mls_copy(other_isec->sid, ssec->peer_sid, &ssec->sid); 3964 3965 return err; 3966 } 3967 3968 static int selinux_socket_unix_may_send(struct socket *sock, 3969 struct socket *other) 3970 { 3971 struct inode_security_struct *isec; 3972 struct inode_security_struct *other_isec; 3973 struct avc_audit_data ad; 3974 int err; 3975 3976 isec = SOCK_INODE(sock)->i_security; 3977 other_isec = SOCK_INODE(other)->i_security; 3978 3979 AVC_AUDIT_DATA_INIT(&ad, NET); 3980 ad.u.net.sk = other->sk; 3981 3982 err = avc_has_perm(isec->sid, other_isec->sid, 3983 isec->sclass, SOCKET__SENDTO, &ad); 3984 if (err) 3985 return err; 3986 3987 return 0; 3988 } 3989 3990 static int selinux_inet_sys_rcv_skb(int ifindex, char *addrp, u16 family, 3991 u32 peer_sid, 3992 struct avc_audit_data *ad) 3993 { 3994 int err; 3995 u32 if_sid; 3996 u32 node_sid; 3997 3998 err = sel_netif_sid(ifindex, &if_sid); 3999 if (err) 4000 return err; 4001 err = avc_has_perm(peer_sid, if_sid, 4002 SECCLASS_NETIF, NETIF__INGRESS, ad); 4003 if (err) 4004 return err; 4005 4006 err = sel_netnode_sid(addrp, family, &node_sid); 4007 if (err) 4008 return err; 4009 return avc_has_perm(peer_sid, node_sid, 4010 SECCLASS_NODE, NODE__RECVFROM, ad); 4011 } 4012 4013 static int selinux_sock_rcv_skb_iptables_compat(struct sock *sk, 4014 struct sk_buff *skb, 4015 struct avc_audit_data *ad, 4016 u16 family, 4017 char *addrp) 4018 { 4019 int err; 4020 struct sk_security_struct *sksec = sk->sk_security; 4021 u16 sk_class; 4022 u32 netif_perm, node_perm, recv_perm; 4023 u32 port_sid, node_sid, if_sid, sk_sid; 4024 4025 sk_sid = sksec->sid; 4026 sk_class = sksec->sclass; 4027 4028 switch (sk_class) { 4029 case SECCLASS_UDP_SOCKET: 4030 netif_perm = NETIF__UDP_RECV; 4031 node_perm = NODE__UDP_RECV; 4032 recv_perm = UDP_SOCKET__RECV_MSG; 4033 break; 4034 case SECCLASS_TCP_SOCKET: 4035 netif_perm = NETIF__TCP_RECV; 4036 node_perm = NODE__TCP_RECV; 4037 recv_perm = TCP_SOCKET__RECV_MSG; 4038 break; 4039 case SECCLASS_DCCP_SOCKET: 4040 netif_perm = NETIF__DCCP_RECV; 4041 node_perm = NODE__DCCP_RECV; 4042 recv_perm = DCCP_SOCKET__RECV_MSG; 4043 break; 4044 default: 4045 netif_perm = NETIF__RAWIP_RECV; 4046 node_perm = NODE__RAWIP_RECV; 4047 recv_perm = 0; 4048 break; 4049 } 4050 4051 err = sel_netif_sid(skb->iif, &if_sid); 4052 if (err) 4053 return err; 4054 err = avc_has_perm(sk_sid, if_sid, SECCLASS_NETIF, netif_perm, ad); 4055 if (err) 4056 return err; 4057 4058 err = sel_netnode_sid(addrp, family, &node_sid); 4059 if (err) 4060 return err; 4061 err = avc_has_perm(sk_sid, node_sid, SECCLASS_NODE, node_perm, ad); 4062 if (err) 4063 return err; 4064 4065 if (!recv_perm) 4066 return 0; 4067 err = sel_netport_sid(sk->sk_protocol, 4068 ntohs(ad->u.net.sport), &port_sid); 4069 if (unlikely(err)) { 4070 printk(KERN_WARNING 4071 "SELinux: failure in" 4072 " selinux_sock_rcv_skb_iptables_compat()," 4073 " network port label not found\n"); 4074 return err; 4075 } 4076 return avc_has_perm(sk_sid, port_sid, sk_class, recv_perm, ad); 4077 } 4078 4079 static int selinux_sock_rcv_skb_compat(struct sock *sk, struct sk_buff *skb, 4080 struct avc_audit_data *ad, 4081 u16 family, char *addrp) 4082 { 4083 int err; 4084 struct sk_security_struct *sksec = sk->sk_security; 4085 u32 peer_sid; 4086 u32 sk_sid = sksec->sid; 4087 4088 if (selinux_compat_net) 4089 err = selinux_sock_rcv_skb_iptables_compat(sk, skb, ad, 4090 family, addrp); 4091 else 4092 err = avc_has_perm(sk_sid, skb->secmark, SECCLASS_PACKET, 4093 PACKET__RECV, ad); 4094 if (err) 4095 return err; 4096 4097 if (selinux_policycap_netpeer) { 4098 err = selinux_skb_peerlbl_sid(skb, family, &peer_sid); 4099 if (err) 4100 return err; 4101 err = avc_has_perm(sk_sid, peer_sid, 4102 SECCLASS_PEER, PEER__RECV, ad); 4103 } else { 4104 err = selinux_netlbl_sock_rcv_skb(sksec, skb, family, ad); 4105 if (err) 4106 return err; 4107 err = selinux_xfrm_sock_rcv_skb(sksec->sid, skb, ad); 4108 } 4109 4110 return err; 4111 } 4112 4113 static int selinux_socket_sock_rcv_skb(struct sock *sk, struct sk_buff *skb) 4114 { 4115 int err; 4116 struct sk_security_struct *sksec = sk->sk_security; 4117 u16 family = sk->sk_family; 4118 u32 sk_sid = sksec->sid; 4119 struct avc_audit_data ad; 4120 char *addrp; 4121 4122 if (family != PF_INET && family != PF_INET6) 4123 return 0; 4124 4125 /* Handle mapped IPv4 packets arriving via IPv6 sockets */ 4126 if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP)) 4127 family = PF_INET; 4128 4129 AVC_AUDIT_DATA_INIT(&ad, NET); 4130 ad.u.net.netif = skb->iif; 4131 ad.u.net.family = family; 4132 err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL); 4133 if (err) 4134 return err; 4135 4136 /* If any sort of compatibility mode is enabled then handoff processing 4137 * to the selinux_sock_rcv_skb_compat() function to deal with the 4138 * special handling. We do this in an attempt to keep this function 4139 * as fast and as clean as possible. */ 4140 if (selinux_compat_net || !selinux_policycap_netpeer) 4141 return selinux_sock_rcv_skb_compat(sk, skb, &ad, 4142 family, addrp); 4143 4144 if (netlbl_enabled() || selinux_xfrm_enabled()) { 4145 u32 peer_sid; 4146 4147 err = selinux_skb_peerlbl_sid(skb, family, &peer_sid); 4148 if (err) 4149 return err; 4150 err = selinux_inet_sys_rcv_skb(skb->iif, addrp, family, 4151 peer_sid, &ad); 4152 if (err) 4153 return err; 4154 err = avc_has_perm(sk_sid, peer_sid, SECCLASS_PEER, 4155 PEER__RECV, &ad); 4156 } 4157 4158 if (selinux_secmark_enabled()) { 4159 err = avc_has_perm(sk_sid, skb->secmark, SECCLASS_PACKET, 4160 PACKET__RECV, &ad); 4161 if (err) 4162 return err; 4163 } 4164 4165 return err; 4166 } 4167 4168 static int selinux_socket_getpeersec_stream(struct socket *sock, char __user *optval, 4169 int __user *optlen, unsigned len) 4170 { 4171 int err = 0; 4172 char *scontext; 4173 u32 scontext_len; 4174 struct sk_security_struct *ssec; 4175 struct inode_security_struct *isec; 4176 u32 peer_sid = SECSID_NULL; 4177 4178 isec = SOCK_INODE(sock)->i_security; 4179 4180 if (isec->sclass == SECCLASS_UNIX_STREAM_SOCKET || 4181 isec->sclass == SECCLASS_TCP_SOCKET) { 4182 ssec = sock->sk->sk_security; 4183 peer_sid = ssec->peer_sid; 4184 } 4185 if (peer_sid == SECSID_NULL) { 4186 err = -ENOPROTOOPT; 4187 goto out; 4188 } 4189 4190 err = security_sid_to_context(peer_sid, &scontext, &scontext_len); 4191 4192 if (err) 4193 goto out; 4194 4195 if (scontext_len > len) { 4196 err = -ERANGE; 4197 goto out_len; 4198 } 4199 4200 if (copy_to_user(optval, scontext, scontext_len)) 4201 err = -EFAULT; 4202 4203 out_len: 4204 if (put_user(scontext_len, optlen)) 4205 err = -EFAULT; 4206 4207 kfree(scontext); 4208 out: 4209 return err; 4210 } 4211 4212 static int selinux_socket_getpeersec_dgram(struct socket *sock, struct sk_buff *skb, u32 *secid) 4213 { 4214 u32 peer_secid = SECSID_NULL; 4215 u16 family; 4216 4217 if (sock) 4218 family = sock->sk->sk_family; 4219 else if (skb && skb->sk) 4220 family = skb->sk->sk_family; 4221 else 4222 goto out; 4223 4224 if (sock && family == PF_UNIX) 4225 selinux_inode_getsecid(SOCK_INODE(sock), &peer_secid); 4226 else if (skb) 4227 selinux_skb_peerlbl_sid(skb, family, &peer_secid); 4228 4229 out: 4230 *secid = peer_secid; 4231 if (peer_secid == SECSID_NULL) 4232 return -EINVAL; 4233 return 0; 4234 } 4235 4236 static int selinux_sk_alloc_security(struct sock *sk, int family, gfp_t priority) 4237 { 4238 return sk_alloc_security(sk, family, priority); 4239 } 4240 4241 static void selinux_sk_free_security(struct sock *sk) 4242 { 4243 sk_free_security(sk); 4244 } 4245 4246 static void selinux_sk_clone_security(const struct sock *sk, struct sock *newsk) 4247 { 4248 struct sk_security_struct *ssec = sk->sk_security; 4249 struct sk_security_struct *newssec = newsk->sk_security; 4250 4251 newssec->sid = ssec->sid; 4252 newssec->peer_sid = ssec->peer_sid; 4253 newssec->sclass = ssec->sclass; 4254 4255 selinux_netlbl_sk_security_reset(newssec, newsk->sk_family); 4256 } 4257 4258 static void selinux_sk_getsecid(struct sock *sk, u32 *secid) 4259 { 4260 if (!sk) 4261 *secid = SECINITSID_ANY_SOCKET; 4262 else { 4263 struct sk_security_struct *sksec = sk->sk_security; 4264 4265 *secid = sksec->sid; 4266 } 4267 } 4268 4269 static void selinux_sock_graft(struct sock *sk, struct socket *parent) 4270 { 4271 struct inode_security_struct *isec = SOCK_INODE(parent)->i_security; 4272 struct sk_security_struct *sksec = sk->sk_security; 4273 4274 if (sk->sk_family == PF_INET || sk->sk_family == PF_INET6 || 4275 sk->sk_family == PF_UNIX) 4276 isec->sid = sksec->sid; 4277 sksec->sclass = isec->sclass; 4278 4279 selinux_netlbl_sock_graft(sk, parent); 4280 } 4281 4282 static int selinux_inet_conn_request(struct sock *sk, struct sk_buff *skb, 4283 struct request_sock *req) 4284 { 4285 struct sk_security_struct *sksec = sk->sk_security; 4286 int err; 4287 u32 newsid; 4288 u32 peersid; 4289 4290 err = selinux_skb_peerlbl_sid(skb, sk->sk_family, &peersid); 4291 if (err) 4292 return err; 4293 if (peersid == SECSID_NULL) { 4294 req->secid = sksec->sid; 4295 req->peer_secid = SECSID_NULL; 4296 return 0; 4297 } 4298 4299 err = security_sid_mls_copy(sksec->sid, peersid, &newsid); 4300 if (err) 4301 return err; 4302 4303 req->secid = newsid; 4304 req->peer_secid = peersid; 4305 return 0; 4306 } 4307 4308 static void selinux_inet_csk_clone(struct sock *newsk, 4309 const struct request_sock *req) 4310 { 4311 struct sk_security_struct *newsksec = newsk->sk_security; 4312 4313 newsksec->sid = req->secid; 4314 newsksec->peer_sid = req->peer_secid; 4315 /* NOTE: Ideally, we should also get the isec->sid for the 4316 new socket in sync, but we don't have the isec available yet. 4317 So we will wait until sock_graft to do it, by which 4318 time it will have been created and available. */ 4319 4320 /* We don't need to take any sort of lock here as we are the only 4321 * thread with access to newsksec */ 4322 selinux_netlbl_sk_security_reset(newsksec, req->rsk_ops->family); 4323 } 4324 4325 static void selinux_inet_conn_established(struct sock *sk, 4326 struct sk_buff *skb) 4327 { 4328 struct sk_security_struct *sksec = sk->sk_security; 4329 4330 selinux_skb_peerlbl_sid(skb, sk->sk_family, &sksec->peer_sid); 4331 } 4332 4333 static void selinux_req_classify_flow(const struct request_sock *req, 4334 struct flowi *fl) 4335 { 4336 fl->secid = req->secid; 4337 } 4338 4339 static int selinux_nlmsg_perm(struct sock *sk, struct sk_buff *skb) 4340 { 4341 int err = 0; 4342 u32 perm; 4343 struct nlmsghdr *nlh; 4344 struct socket *sock = sk->sk_socket; 4345 struct inode_security_struct *isec = SOCK_INODE(sock)->i_security; 4346 4347 if (skb->len < NLMSG_SPACE(0)) { 4348 err = -EINVAL; 4349 goto out; 4350 } 4351 nlh = nlmsg_hdr(skb); 4352 4353 err = selinux_nlmsg_lookup(isec->sclass, nlh->nlmsg_type, &perm); 4354 if (err) { 4355 if (err == -EINVAL) { 4356 audit_log(current->audit_context, GFP_KERNEL, AUDIT_SELINUX_ERR, 4357 "SELinux: unrecognized netlink message" 4358 " type=%hu for sclass=%hu\n", 4359 nlh->nlmsg_type, isec->sclass); 4360 if (!selinux_enforcing) 4361 err = 0; 4362 } 4363 4364 /* Ignore */ 4365 if (err == -ENOENT) 4366 err = 0; 4367 goto out; 4368 } 4369 4370 err = socket_has_perm(current, sock, perm); 4371 out: 4372 return err; 4373 } 4374 4375 #ifdef CONFIG_NETFILTER 4376 4377 static unsigned int selinux_ip_forward(struct sk_buff *skb, int ifindex, 4378 u16 family) 4379 { 4380 char *addrp; 4381 u32 peer_sid; 4382 struct avc_audit_data ad; 4383 u8 secmark_active; 4384 u8 peerlbl_active; 4385 4386 if (!selinux_policycap_netpeer) 4387 return NF_ACCEPT; 4388 4389 secmark_active = selinux_secmark_enabled(); 4390 peerlbl_active = netlbl_enabled() || selinux_xfrm_enabled(); 4391 if (!secmark_active && !peerlbl_active) 4392 return NF_ACCEPT; 4393 4394 AVC_AUDIT_DATA_INIT(&ad, NET); 4395 ad.u.net.netif = ifindex; 4396 ad.u.net.family = family; 4397 if (selinux_parse_skb(skb, &ad, &addrp, 1, NULL) != 0) 4398 return NF_DROP; 4399 4400 if (selinux_skb_peerlbl_sid(skb, family, &peer_sid) != 0) 4401 return NF_DROP; 4402 4403 if (peerlbl_active) 4404 if (selinux_inet_sys_rcv_skb(ifindex, addrp, family, 4405 peer_sid, &ad) != 0) 4406 return NF_DROP; 4407 4408 if (secmark_active) 4409 if (avc_has_perm(peer_sid, skb->secmark, 4410 SECCLASS_PACKET, PACKET__FORWARD_IN, &ad)) 4411 return NF_DROP; 4412 4413 return NF_ACCEPT; 4414 } 4415 4416 static unsigned int selinux_ipv4_forward(unsigned int hooknum, 4417 struct sk_buff *skb, 4418 const struct net_device *in, 4419 const struct net_device *out, 4420 int (*okfn)(struct sk_buff *)) 4421 { 4422 return selinux_ip_forward(skb, in->ifindex, PF_INET); 4423 } 4424 4425 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE) 4426 static unsigned int selinux_ipv6_forward(unsigned int hooknum, 4427 struct sk_buff *skb, 4428 const struct net_device *in, 4429 const struct net_device *out, 4430 int (*okfn)(struct sk_buff *)) 4431 { 4432 return selinux_ip_forward(skb, in->ifindex, PF_INET6); 4433 } 4434 #endif /* IPV6 */ 4435 4436 static int selinux_ip_postroute_iptables_compat(struct sock *sk, 4437 int ifindex, 4438 struct avc_audit_data *ad, 4439 u16 family, char *addrp) 4440 { 4441 int err; 4442 struct sk_security_struct *sksec = sk->sk_security; 4443 u16 sk_class; 4444 u32 netif_perm, node_perm, send_perm; 4445 u32 port_sid, node_sid, if_sid, sk_sid; 4446 4447 sk_sid = sksec->sid; 4448 sk_class = sksec->sclass; 4449 4450 switch (sk_class) { 4451 case SECCLASS_UDP_SOCKET: 4452 netif_perm = NETIF__UDP_SEND; 4453 node_perm = NODE__UDP_SEND; 4454 send_perm = UDP_SOCKET__SEND_MSG; 4455 break; 4456 case SECCLASS_TCP_SOCKET: 4457 netif_perm = NETIF__TCP_SEND; 4458 node_perm = NODE__TCP_SEND; 4459 send_perm = TCP_SOCKET__SEND_MSG; 4460 break; 4461 case SECCLASS_DCCP_SOCKET: 4462 netif_perm = NETIF__DCCP_SEND; 4463 node_perm = NODE__DCCP_SEND; 4464 send_perm = DCCP_SOCKET__SEND_MSG; 4465 break; 4466 default: 4467 netif_perm = NETIF__RAWIP_SEND; 4468 node_perm = NODE__RAWIP_SEND; 4469 send_perm = 0; 4470 break; 4471 } 4472 4473 err = sel_netif_sid(ifindex, &if_sid); 4474 if (err) 4475 return err; 4476 err = avc_has_perm(sk_sid, if_sid, SECCLASS_NETIF, netif_perm, ad); 4477 return err; 4478 4479 err = sel_netnode_sid(addrp, family, &node_sid); 4480 if (err) 4481 return err; 4482 err = avc_has_perm(sk_sid, node_sid, SECCLASS_NODE, node_perm, ad); 4483 if (err) 4484 return err; 4485 4486 if (send_perm != 0) 4487 return 0; 4488 4489 err = sel_netport_sid(sk->sk_protocol, 4490 ntohs(ad->u.net.dport), &port_sid); 4491 if (unlikely(err)) { 4492 printk(KERN_WARNING 4493 "SELinux: failure in" 4494 " selinux_ip_postroute_iptables_compat()," 4495 " network port label not found\n"); 4496 return err; 4497 } 4498 return avc_has_perm(sk_sid, port_sid, sk_class, send_perm, ad); 4499 } 4500 4501 static unsigned int selinux_ip_postroute_compat(struct sk_buff *skb, 4502 int ifindex, 4503 struct avc_audit_data *ad, 4504 u16 family, 4505 char *addrp, 4506 u8 proto) 4507 { 4508 struct sock *sk = skb->sk; 4509 struct sk_security_struct *sksec; 4510 4511 if (sk == NULL) 4512 return NF_ACCEPT; 4513 sksec = sk->sk_security; 4514 4515 if (selinux_compat_net) { 4516 if (selinux_ip_postroute_iptables_compat(skb->sk, ifindex, 4517 ad, family, addrp)) 4518 return NF_DROP; 4519 } else { 4520 if (avc_has_perm(sksec->sid, skb->secmark, 4521 SECCLASS_PACKET, PACKET__SEND, ad)) 4522 return NF_DROP; 4523 } 4524 4525 if (selinux_policycap_netpeer) 4526 if (selinux_xfrm_postroute_last(sksec->sid, skb, ad, proto)) 4527 return NF_DROP; 4528 4529 return NF_ACCEPT; 4530 } 4531 4532 static unsigned int selinux_ip_postroute(struct sk_buff *skb, int ifindex, 4533 u16 family) 4534 { 4535 u32 secmark_perm; 4536 u32 peer_sid; 4537 struct sock *sk; 4538 struct avc_audit_data ad; 4539 char *addrp; 4540 u8 proto; 4541 u8 secmark_active; 4542 u8 peerlbl_active; 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, &proto)) 4548 return NF_DROP; 4549 4550 /* If any sort of compatibility mode is enabled then handoff processing 4551 * to the selinux_ip_postroute_compat() function to deal with the 4552 * special handling. We do this in an attempt to keep this function 4553 * as fast and as clean as possible. */ 4554 if (selinux_compat_net || !selinux_policycap_netpeer) 4555 return selinux_ip_postroute_compat(skb, ifindex, &ad, 4556 family, addrp, proto); 4557 4558 /* If skb->dst->xfrm is non-NULL then the packet is undergoing an IPsec 4559 * packet transformation so allow the packet to pass without any checks 4560 * since we'll have another chance to perform access control checks 4561 * when the packet is on it's final way out. 4562 * NOTE: there appear to be some IPv6 multicast cases where skb->dst 4563 * is NULL, in this case go ahead and apply access control. */ 4564 if (skb->dst != NULL && skb->dst->xfrm != NULL) 4565 return NF_ACCEPT; 4566 4567 secmark_active = selinux_secmark_enabled(); 4568 peerlbl_active = netlbl_enabled() || selinux_xfrm_enabled(); 4569 if (!secmark_active && !peerlbl_active) 4570 return NF_ACCEPT; 4571 4572 /* if the packet is locally generated (skb->sk != NULL) then use the 4573 * socket's label as the peer label, otherwise the packet is being 4574 * forwarded through this system and we need to fetch the peer label 4575 * directly from the packet */ 4576 sk = skb->sk; 4577 if (sk) { 4578 struct sk_security_struct *sksec = sk->sk_security; 4579 peer_sid = sksec->sid; 4580 secmark_perm = PACKET__SEND; 4581 } else { 4582 if (selinux_skb_peerlbl_sid(skb, family, &peer_sid)) 4583 return NF_DROP; 4584 secmark_perm = PACKET__FORWARD_OUT; 4585 } 4586 4587 if (secmark_active) 4588 if (avc_has_perm(peer_sid, skb->secmark, 4589 SECCLASS_PACKET, secmark_perm, &ad)) 4590 return NF_DROP; 4591 4592 if (peerlbl_active) { 4593 u32 if_sid; 4594 u32 node_sid; 4595 4596 if (sel_netif_sid(ifindex, &if_sid)) 4597 return NF_DROP; 4598 if (avc_has_perm(peer_sid, if_sid, 4599 SECCLASS_NETIF, NETIF__EGRESS, &ad)) 4600 return NF_DROP; 4601 4602 if (sel_netnode_sid(addrp, family, &node_sid)) 4603 return NF_DROP; 4604 if (avc_has_perm(peer_sid, node_sid, 4605 SECCLASS_NODE, NODE__SENDTO, &ad)) 4606 return NF_DROP; 4607 } 4608 4609 return NF_ACCEPT; 4610 } 4611 4612 static unsigned int selinux_ipv4_postroute(unsigned int hooknum, 4613 struct sk_buff *skb, 4614 const struct net_device *in, 4615 const struct net_device *out, 4616 int (*okfn)(struct sk_buff *)) 4617 { 4618 return selinux_ip_postroute(skb, out->ifindex, PF_INET); 4619 } 4620 4621 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE) 4622 static unsigned int selinux_ipv6_postroute(unsigned int hooknum, 4623 struct sk_buff *skb, 4624 const struct net_device *in, 4625 const struct net_device *out, 4626 int (*okfn)(struct sk_buff *)) 4627 { 4628 return selinux_ip_postroute(skb, out->ifindex, PF_INET6); 4629 } 4630 #endif /* IPV6 */ 4631 4632 #endif /* CONFIG_NETFILTER */ 4633 4634 static int selinux_netlink_send(struct sock *sk, struct sk_buff *skb) 4635 { 4636 int err; 4637 4638 err = secondary_ops->netlink_send(sk, skb); 4639 if (err) 4640 return err; 4641 4642 if (policydb_loaded_version >= POLICYDB_VERSION_NLCLASS) 4643 err = selinux_nlmsg_perm(sk, skb); 4644 4645 return err; 4646 } 4647 4648 static int selinux_netlink_recv(struct sk_buff *skb, int capability) 4649 { 4650 int err; 4651 struct avc_audit_data ad; 4652 4653 err = secondary_ops->netlink_recv(skb, capability); 4654 if (err) 4655 return err; 4656 4657 AVC_AUDIT_DATA_INIT(&ad, CAP); 4658 ad.u.cap = capability; 4659 4660 return avc_has_perm(NETLINK_CB(skb).sid, NETLINK_CB(skb).sid, 4661 SECCLASS_CAPABILITY, CAP_TO_MASK(capability), &ad); 4662 } 4663 4664 static int ipc_alloc_security(struct task_struct *task, 4665 struct kern_ipc_perm *perm, 4666 u16 sclass) 4667 { 4668 struct task_security_struct *tsec = task->security; 4669 struct ipc_security_struct *isec; 4670 4671 isec = kzalloc(sizeof(struct ipc_security_struct), GFP_KERNEL); 4672 if (!isec) 4673 return -ENOMEM; 4674 4675 isec->sclass = sclass; 4676 isec->sid = tsec->sid; 4677 perm->security = isec; 4678 4679 return 0; 4680 } 4681 4682 static void ipc_free_security(struct kern_ipc_perm *perm) 4683 { 4684 struct ipc_security_struct *isec = perm->security; 4685 perm->security = NULL; 4686 kfree(isec); 4687 } 4688 4689 static int msg_msg_alloc_security(struct msg_msg *msg) 4690 { 4691 struct msg_security_struct *msec; 4692 4693 msec = kzalloc(sizeof(struct msg_security_struct), GFP_KERNEL); 4694 if (!msec) 4695 return -ENOMEM; 4696 4697 msec->sid = SECINITSID_UNLABELED; 4698 msg->security = msec; 4699 4700 return 0; 4701 } 4702 4703 static void msg_msg_free_security(struct msg_msg *msg) 4704 { 4705 struct msg_security_struct *msec = msg->security; 4706 4707 msg->security = NULL; 4708 kfree(msec); 4709 } 4710 4711 static int ipc_has_perm(struct kern_ipc_perm *ipc_perms, 4712 u32 perms) 4713 { 4714 struct task_security_struct *tsec; 4715 struct ipc_security_struct *isec; 4716 struct avc_audit_data ad; 4717 4718 tsec = current->security; 4719 isec = ipc_perms->security; 4720 4721 AVC_AUDIT_DATA_INIT(&ad, IPC); 4722 ad.u.ipc_id = ipc_perms->key; 4723 4724 return avc_has_perm(tsec->sid, isec->sid, isec->sclass, perms, &ad); 4725 } 4726 4727 static int selinux_msg_msg_alloc_security(struct msg_msg *msg) 4728 { 4729 return msg_msg_alloc_security(msg); 4730 } 4731 4732 static void selinux_msg_msg_free_security(struct msg_msg *msg) 4733 { 4734 msg_msg_free_security(msg); 4735 } 4736 4737 /* message queue security operations */ 4738 static int selinux_msg_queue_alloc_security(struct msg_queue *msq) 4739 { 4740 struct task_security_struct *tsec; 4741 struct ipc_security_struct *isec; 4742 struct avc_audit_data ad; 4743 int rc; 4744 4745 rc = ipc_alloc_security(current, &msq->q_perm, SECCLASS_MSGQ); 4746 if (rc) 4747 return rc; 4748 4749 tsec = current->security; 4750 isec = msq->q_perm.security; 4751 4752 AVC_AUDIT_DATA_INIT(&ad, IPC); 4753 ad.u.ipc_id = msq->q_perm.key; 4754 4755 rc = avc_has_perm(tsec->sid, isec->sid, SECCLASS_MSGQ, 4756 MSGQ__CREATE, &ad); 4757 if (rc) { 4758 ipc_free_security(&msq->q_perm); 4759 return rc; 4760 } 4761 return 0; 4762 } 4763 4764 static void selinux_msg_queue_free_security(struct msg_queue *msq) 4765 { 4766 ipc_free_security(&msq->q_perm); 4767 } 4768 4769 static int selinux_msg_queue_associate(struct msg_queue *msq, int msqflg) 4770 { 4771 struct task_security_struct *tsec; 4772 struct ipc_security_struct *isec; 4773 struct avc_audit_data ad; 4774 4775 tsec = current->security; 4776 isec = msq->q_perm.security; 4777 4778 AVC_AUDIT_DATA_INIT(&ad, IPC); 4779 ad.u.ipc_id = msq->q_perm.key; 4780 4781 return avc_has_perm(tsec->sid, isec->sid, SECCLASS_MSGQ, 4782 MSGQ__ASSOCIATE, &ad); 4783 } 4784 4785 static int selinux_msg_queue_msgctl(struct msg_queue *msq, int cmd) 4786 { 4787 int err; 4788 int perms; 4789 4790 switch (cmd) { 4791 case IPC_INFO: 4792 case MSG_INFO: 4793 /* No specific object, just general system-wide information. */ 4794 return task_has_system(current, SYSTEM__IPC_INFO); 4795 case IPC_STAT: 4796 case MSG_STAT: 4797 perms = MSGQ__GETATTR | MSGQ__ASSOCIATE; 4798 break; 4799 case IPC_SET: 4800 perms = MSGQ__SETATTR; 4801 break; 4802 case IPC_RMID: 4803 perms = MSGQ__DESTROY; 4804 break; 4805 default: 4806 return 0; 4807 } 4808 4809 err = ipc_has_perm(&msq->q_perm, perms); 4810 return err; 4811 } 4812 4813 static int selinux_msg_queue_msgsnd(struct msg_queue *msq, struct msg_msg *msg, int msqflg) 4814 { 4815 struct task_security_struct *tsec; 4816 struct ipc_security_struct *isec; 4817 struct msg_security_struct *msec; 4818 struct avc_audit_data ad; 4819 int rc; 4820 4821 tsec = current->security; 4822 isec = msq->q_perm.security; 4823 msec = msg->security; 4824 4825 /* 4826 * First time through, need to assign label to the message 4827 */ 4828 if (msec->sid == SECINITSID_UNLABELED) { 4829 /* 4830 * Compute new sid based on current process and 4831 * message queue this message will be stored in 4832 */ 4833 rc = security_transition_sid(tsec->sid, 4834 isec->sid, 4835 SECCLASS_MSG, 4836 &msec->sid); 4837 if (rc) 4838 return rc; 4839 } 4840 4841 AVC_AUDIT_DATA_INIT(&ad, IPC); 4842 ad.u.ipc_id = msq->q_perm.key; 4843 4844 /* Can this process write to the queue? */ 4845 rc = avc_has_perm(tsec->sid, isec->sid, SECCLASS_MSGQ, 4846 MSGQ__WRITE, &ad); 4847 if (!rc) 4848 /* Can this process send the message */ 4849 rc = avc_has_perm(tsec->sid, msec->sid, 4850 SECCLASS_MSG, MSG__SEND, &ad); 4851 if (!rc) 4852 /* Can the message be put in the queue? */ 4853 rc = avc_has_perm(msec->sid, isec->sid, 4854 SECCLASS_MSGQ, MSGQ__ENQUEUE, &ad); 4855 4856 return rc; 4857 } 4858 4859 static int selinux_msg_queue_msgrcv(struct msg_queue *msq, struct msg_msg *msg, 4860 struct task_struct *target, 4861 long type, int mode) 4862 { 4863 struct task_security_struct *tsec; 4864 struct ipc_security_struct *isec; 4865 struct msg_security_struct *msec; 4866 struct avc_audit_data ad; 4867 int rc; 4868 4869 tsec = target->security; 4870 isec = msq->q_perm.security; 4871 msec = msg->security; 4872 4873 AVC_AUDIT_DATA_INIT(&ad, IPC); 4874 ad.u.ipc_id = msq->q_perm.key; 4875 4876 rc = avc_has_perm(tsec->sid, isec->sid, 4877 SECCLASS_MSGQ, MSGQ__READ, &ad); 4878 if (!rc) 4879 rc = avc_has_perm(tsec->sid, msec->sid, 4880 SECCLASS_MSG, MSG__RECEIVE, &ad); 4881 return rc; 4882 } 4883 4884 /* Shared Memory security operations */ 4885 static int selinux_shm_alloc_security(struct shmid_kernel *shp) 4886 { 4887 struct task_security_struct *tsec; 4888 struct ipc_security_struct *isec; 4889 struct avc_audit_data ad; 4890 int rc; 4891 4892 rc = ipc_alloc_security(current, &shp->shm_perm, SECCLASS_SHM); 4893 if (rc) 4894 return rc; 4895 4896 tsec = current->security; 4897 isec = shp->shm_perm.security; 4898 4899 AVC_AUDIT_DATA_INIT(&ad, IPC); 4900 ad.u.ipc_id = shp->shm_perm.key; 4901 4902 rc = avc_has_perm(tsec->sid, isec->sid, SECCLASS_SHM, 4903 SHM__CREATE, &ad); 4904 if (rc) { 4905 ipc_free_security(&shp->shm_perm); 4906 return rc; 4907 } 4908 return 0; 4909 } 4910 4911 static void selinux_shm_free_security(struct shmid_kernel *shp) 4912 { 4913 ipc_free_security(&shp->shm_perm); 4914 } 4915 4916 static int selinux_shm_associate(struct shmid_kernel *shp, int shmflg) 4917 { 4918 struct task_security_struct *tsec; 4919 struct ipc_security_struct *isec; 4920 struct avc_audit_data ad; 4921 4922 tsec = current->security; 4923 isec = shp->shm_perm.security; 4924 4925 AVC_AUDIT_DATA_INIT(&ad, IPC); 4926 ad.u.ipc_id = shp->shm_perm.key; 4927 4928 return avc_has_perm(tsec->sid, isec->sid, SECCLASS_SHM, 4929 SHM__ASSOCIATE, &ad); 4930 } 4931 4932 /* Note, at this point, shp is locked down */ 4933 static int selinux_shm_shmctl(struct shmid_kernel *shp, int cmd) 4934 { 4935 int perms; 4936 int err; 4937 4938 switch (cmd) { 4939 case IPC_INFO: 4940 case SHM_INFO: 4941 /* No specific object, just general system-wide information. */ 4942 return task_has_system(current, SYSTEM__IPC_INFO); 4943 case IPC_STAT: 4944 case SHM_STAT: 4945 perms = SHM__GETATTR | SHM__ASSOCIATE; 4946 break; 4947 case IPC_SET: 4948 perms = SHM__SETATTR; 4949 break; 4950 case SHM_LOCK: 4951 case SHM_UNLOCK: 4952 perms = SHM__LOCK; 4953 break; 4954 case IPC_RMID: 4955 perms = SHM__DESTROY; 4956 break; 4957 default: 4958 return 0; 4959 } 4960 4961 err = ipc_has_perm(&shp->shm_perm, perms); 4962 return err; 4963 } 4964 4965 static int selinux_shm_shmat(struct shmid_kernel *shp, 4966 char __user *shmaddr, int shmflg) 4967 { 4968 u32 perms; 4969 int rc; 4970 4971 rc = secondary_ops->shm_shmat(shp, shmaddr, shmflg); 4972 if (rc) 4973 return rc; 4974 4975 if (shmflg & SHM_RDONLY) 4976 perms = SHM__READ; 4977 else 4978 perms = SHM__READ | SHM__WRITE; 4979 4980 return ipc_has_perm(&shp->shm_perm, perms); 4981 } 4982 4983 /* Semaphore security operations */ 4984 static int selinux_sem_alloc_security(struct sem_array *sma) 4985 { 4986 struct task_security_struct *tsec; 4987 struct ipc_security_struct *isec; 4988 struct avc_audit_data ad; 4989 int rc; 4990 4991 rc = ipc_alloc_security(current, &sma->sem_perm, SECCLASS_SEM); 4992 if (rc) 4993 return rc; 4994 4995 tsec = current->security; 4996 isec = sma->sem_perm.security; 4997 4998 AVC_AUDIT_DATA_INIT(&ad, IPC); 4999 ad.u.ipc_id = sma->sem_perm.key; 5000 5001 rc = avc_has_perm(tsec->sid, isec->sid, SECCLASS_SEM, 5002 SEM__CREATE, &ad); 5003 if (rc) { 5004 ipc_free_security(&sma->sem_perm); 5005 return rc; 5006 } 5007 return 0; 5008 } 5009 5010 static void selinux_sem_free_security(struct sem_array *sma) 5011 { 5012 ipc_free_security(&sma->sem_perm); 5013 } 5014 5015 static int selinux_sem_associate(struct sem_array *sma, int semflg) 5016 { 5017 struct task_security_struct *tsec; 5018 struct ipc_security_struct *isec; 5019 struct avc_audit_data ad; 5020 5021 tsec = current->security; 5022 isec = sma->sem_perm.security; 5023 5024 AVC_AUDIT_DATA_INIT(&ad, IPC); 5025 ad.u.ipc_id = sma->sem_perm.key; 5026 5027 return avc_has_perm(tsec->sid, isec->sid, SECCLASS_SEM, 5028 SEM__ASSOCIATE, &ad); 5029 } 5030 5031 /* Note, at this point, sma is locked down */ 5032 static int selinux_sem_semctl(struct sem_array *sma, int cmd) 5033 { 5034 int err; 5035 u32 perms; 5036 5037 switch (cmd) { 5038 case IPC_INFO: 5039 case SEM_INFO: 5040 /* No specific object, just general system-wide information. */ 5041 return task_has_system(current, SYSTEM__IPC_INFO); 5042 case GETPID: 5043 case GETNCNT: 5044 case GETZCNT: 5045 perms = SEM__GETATTR; 5046 break; 5047 case GETVAL: 5048 case GETALL: 5049 perms = SEM__READ; 5050 break; 5051 case SETVAL: 5052 case SETALL: 5053 perms = SEM__WRITE; 5054 break; 5055 case IPC_RMID: 5056 perms = SEM__DESTROY; 5057 break; 5058 case IPC_SET: 5059 perms = SEM__SETATTR; 5060 break; 5061 case IPC_STAT: 5062 case SEM_STAT: 5063 perms = SEM__GETATTR | SEM__ASSOCIATE; 5064 break; 5065 default: 5066 return 0; 5067 } 5068 5069 err = ipc_has_perm(&sma->sem_perm, perms); 5070 return err; 5071 } 5072 5073 static int selinux_sem_semop(struct sem_array *sma, 5074 struct sembuf *sops, unsigned nsops, int alter) 5075 { 5076 u32 perms; 5077 5078 if (alter) 5079 perms = SEM__READ | SEM__WRITE; 5080 else 5081 perms = SEM__READ; 5082 5083 return ipc_has_perm(&sma->sem_perm, perms); 5084 } 5085 5086 static int selinux_ipc_permission(struct kern_ipc_perm *ipcp, short flag) 5087 { 5088 u32 av = 0; 5089 5090 av = 0; 5091 if (flag & S_IRUGO) 5092 av |= IPC__UNIX_READ; 5093 if (flag & S_IWUGO) 5094 av |= IPC__UNIX_WRITE; 5095 5096 if (av == 0) 5097 return 0; 5098 5099 return ipc_has_perm(ipcp, av); 5100 } 5101 5102 static void selinux_ipc_getsecid(struct kern_ipc_perm *ipcp, u32 *secid) 5103 { 5104 struct ipc_security_struct *isec = ipcp->security; 5105 *secid = isec->sid; 5106 } 5107 5108 static void selinux_d_instantiate(struct dentry *dentry, struct inode *inode) 5109 { 5110 if (inode) 5111 inode_doinit_with_dentry(inode, dentry); 5112 } 5113 5114 static int selinux_getprocattr(struct task_struct *p, 5115 char *name, char **value) 5116 { 5117 struct task_security_struct *tsec; 5118 u32 sid; 5119 int error; 5120 unsigned len; 5121 5122 if (current != p) { 5123 error = task_has_perm(current, p, PROCESS__GETATTR); 5124 if (error) 5125 return error; 5126 } 5127 5128 tsec = p->security; 5129 5130 if (!strcmp(name, "current")) 5131 sid = tsec->sid; 5132 else if (!strcmp(name, "prev")) 5133 sid = tsec->osid; 5134 else if (!strcmp(name, "exec")) 5135 sid = tsec->exec_sid; 5136 else if (!strcmp(name, "fscreate")) 5137 sid = tsec->create_sid; 5138 else if (!strcmp(name, "keycreate")) 5139 sid = tsec->keycreate_sid; 5140 else if (!strcmp(name, "sockcreate")) 5141 sid = tsec->sockcreate_sid; 5142 else 5143 return -EINVAL; 5144 5145 if (!sid) 5146 return 0; 5147 5148 error = security_sid_to_context(sid, value, &len); 5149 if (error) 5150 return error; 5151 return len; 5152 } 5153 5154 static int selinux_setprocattr(struct task_struct *p, 5155 char *name, void *value, size_t size) 5156 { 5157 struct task_security_struct *tsec; 5158 struct task_struct *tracer; 5159 u32 sid = 0; 5160 int error; 5161 char *str = value; 5162 5163 if (current != p) { 5164 /* SELinux only allows a process to change its own 5165 security attributes. */ 5166 return -EACCES; 5167 } 5168 5169 /* 5170 * Basic control over ability to set these attributes at all. 5171 * current == p, but we'll pass them separately in case the 5172 * above restriction is ever removed. 5173 */ 5174 if (!strcmp(name, "exec")) 5175 error = task_has_perm(current, p, PROCESS__SETEXEC); 5176 else if (!strcmp(name, "fscreate")) 5177 error = task_has_perm(current, p, PROCESS__SETFSCREATE); 5178 else if (!strcmp(name, "keycreate")) 5179 error = task_has_perm(current, p, PROCESS__SETKEYCREATE); 5180 else if (!strcmp(name, "sockcreate")) 5181 error = task_has_perm(current, p, PROCESS__SETSOCKCREATE); 5182 else if (!strcmp(name, "current")) 5183 error = task_has_perm(current, p, PROCESS__SETCURRENT); 5184 else 5185 error = -EINVAL; 5186 if (error) 5187 return error; 5188 5189 /* Obtain a SID for the context, if one was specified. */ 5190 if (size && str[1] && str[1] != '\n') { 5191 if (str[size-1] == '\n') { 5192 str[size-1] = 0; 5193 size--; 5194 } 5195 error = security_context_to_sid(value, size, &sid); 5196 if (error == -EINVAL && !strcmp(name, "fscreate")) { 5197 if (!capable(CAP_MAC_ADMIN)) 5198 return error; 5199 error = security_context_to_sid_force(value, size, 5200 &sid); 5201 } 5202 if (error) 5203 return error; 5204 } 5205 5206 /* Permission checking based on the specified context is 5207 performed during the actual operation (execve, 5208 open/mkdir/...), when we know the full context of the 5209 operation. See selinux_bprm_set_security for the execve 5210 checks and may_create for the file creation checks. The 5211 operation will then fail if the context is not permitted. */ 5212 tsec = p->security; 5213 if (!strcmp(name, "exec")) 5214 tsec->exec_sid = sid; 5215 else if (!strcmp(name, "fscreate")) 5216 tsec->create_sid = sid; 5217 else if (!strcmp(name, "keycreate")) { 5218 error = may_create_key(sid, p); 5219 if (error) 5220 return error; 5221 tsec->keycreate_sid = sid; 5222 } else if (!strcmp(name, "sockcreate")) 5223 tsec->sockcreate_sid = sid; 5224 else if (!strcmp(name, "current")) { 5225 struct av_decision avd; 5226 5227 if (sid == 0) 5228 return -EINVAL; 5229 /* 5230 * SELinux allows to change context in the following case only. 5231 * - Single threaded processes. 5232 * - Multi threaded processes intend to change its context into 5233 * more restricted domain (defined by TYPEBOUNDS statement). 5234 */ 5235 if (atomic_read(&p->mm->mm_users) != 1) { 5236 struct task_struct *g, *t; 5237 struct mm_struct *mm = p->mm; 5238 read_lock(&tasklist_lock); 5239 do_each_thread(g, t) { 5240 if (t->mm == mm && t != p) { 5241 read_unlock(&tasklist_lock); 5242 error = security_bounded_transition(tsec->sid, sid); 5243 if (!error) 5244 goto boundary_ok; 5245 5246 return error; 5247 } 5248 } while_each_thread(g, t); 5249 read_unlock(&tasklist_lock); 5250 } 5251 boundary_ok: 5252 5253 /* Check permissions for the transition. */ 5254 error = avc_has_perm(tsec->sid, sid, SECCLASS_PROCESS, 5255 PROCESS__DYNTRANSITION, NULL); 5256 if (error) 5257 return error; 5258 5259 /* Check for ptracing, and update the task SID if ok. 5260 Otherwise, leave SID unchanged and fail. */ 5261 task_lock(p); 5262 rcu_read_lock(); 5263 tracer = tracehook_tracer_task(p); 5264 if (tracer != NULL) { 5265 struct task_security_struct *ptsec = tracer->security; 5266 u32 ptsid = ptsec->sid; 5267 rcu_read_unlock(); 5268 error = avc_has_perm_noaudit(ptsid, sid, 5269 SECCLASS_PROCESS, 5270 PROCESS__PTRACE, 0, &avd); 5271 if (!error) 5272 tsec->sid = sid; 5273 task_unlock(p); 5274 avc_audit(ptsid, sid, SECCLASS_PROCESS, 5275 PROCESS__PTRACE, &avd, error, NULL); 5276 if (error) 5277 return error; 5278 } else { 5279 rcu_read_unlock(); 5280 tsec->sid = sid; 5281 task_unlock(p); 5282 } 5283 } else 5284 return -EINVAL; 5285 5286 return size; 5287 } 5288 5289 static int selinux_secid_to_secctx(u32 secid, char **secdata, u32 *seclen) 5290 { 5291 return security_sid_to_context(secid, secdata, seclen); 5292 } 5293 5294 static int selinux_secctx_to_secid(const char *secdata, u32 seclen, u32 *secid) 5295 { 5296 return security_context_to_sid(secdata, seclen, secid); 5297 } 5298 5299 static void selinux_release_secctx(char *secdata, u32 seclen) 5300 { 5301 kfree(secdata); 5302 } 5303 5304 #ifdef CONFIG_KEYS 5305 5306 static int selinux_key_alloc(struct key *k, struct task_struct *tsk, 5307 unsigned long flags) 5308 { 5309 struct task_security_struct *tsec = tsk->security; 5310 struct key_security_struct *ksec; 5311 5312 ksec = kzalloc(sizeof(struct key_security_struct), GFP_KERNEL); 5313 if (!ksec) 5314 return -ENOMEM; 5315 5316 if (tsec->keycreate_sid) 5317 ksec->sid = tsec->keycreate_sid; 5318 else 5319 ksec->sid = tsec->sid; 5320 k->security = ksec; 5321 5322 return 0; 5323 } 5324 5325 static void selinux_key_free(struct key *k) 5326 { 5327 struct key_security_struct *ksec = k->security; 5328 5329 k->security = NULL; 5330 kfree(ksec); 5331 } 5332 5333 static int selinux_key_permission(key_ref_t key_ref, 5334 struct task_struct *ctx, 5335 key_perm_t perm) 5336 { 5337 struct key *key; 5338 struct task_security_struct *tsec; 5339 struct key_security_struct *ksec; 5340 5341 key = key_ref_to_ptr(key_ref); 5342 5343 tsec = ctx->security; 5344 ksec = key->security; 5345 5346 /* if no specific permissions are requested, we skip the 5347 permission check. No serious, additional covert channels 5348 appear to be created. */ 5349 if (perm == 0) 5350 return 0; 5351 5352 return avc_has_perm(tsec->sid, ksec->sid, 5353 SECCLASS_KEY, perm, NULL); 5354 } 5355 5356 static int selinux_key_getsecurity(struct key *key, char **_buffer) 5357 { 5358 struct key_security_struct *ksec = key->security; 5359 char *context = NULL; 5360 unsigned len; 5361 int rc; 5362 5363 rc = security_sid_to_context(ksec->sid, &context, &len); 5364 if (!rc) 5365 rc = len; 5366 *_buffer = context; 5367 return rc; 5368 } 5369 5370 #endif 5371 5372 static struct security_operations selinux_ops = { 5373 .name = "selinux", 5374 5375 .ptrace_may_access = selinux_ptrace_may_access, 5376 .ptrace_traceme = selinux_ptrace_traceme, 5377 .capget = selinux_capget, 5378 .capset_check = selinux_capset_check, 5379 .capset_set = selinux_capset_set, 5380 .sysctl = selinux_sysctl, 5381 .capable = selinux_capable, 5382 .quotactl = selinux_quotactl, 5383 .quota_on = selinux_quota_on, 5384 .syslog = selinux_syslog, 5385 .vm_enough_memory = selinux_vm_enough_memory, 5386 5387 .netlink_send = selinux_netlink_send, 5388 .netlink_recv = selinux_netlink_recv, 5389 5390 .bprm_alloc_security = selinux_bprm_alloc_security, 5391 .bprm_free_security = selinux_bprm_free_security, 5392 .bprm_apply_creds = selinux_bprm_apply_creds, 5393 .bprm_post_apply_creds = selinux_bprm_post_apply_creds, 5394 .bprm_set_security = selinux_bprm_set_security, 5395 .bprm_check_security = selinux_bprm_check_security, 5396 .bprm_secureexec = selinux_bprm_secureexec, 5397 5398 .sb_alloc_security = selinux_sb_alloc_security, 5399 .sb_free_security = selinux_sb_free_security, 5400 .sb_copy_data = selinux_sb_copy_data, 5401 .sb_kern_mount = selinux_sb_kern_mount, 5402 .sb_show_options = selinux_sb_show_options, 5403 .sb_statfs = selinux_sb_statfs, 5404 .sb_mount = selinux_mount, 5405 .sb_umount = selinux_umount, 5406 .sb_set_mnt_opts = selinux_set_mnt_opts, 5407 .sb_clone_mnt_opts = selinux_sb_clone_mnt_opts, 5408 .sb_parse_opts_str = selinux_parse_opts_str, 5409 5410 5411 .inode_alloc_security = selinux_inode_alloc_security, 5412 .inode_free_security = selinux_inode_free_security, 5413 .inode_init_security = selinux_inode_init_security, 5414 .inode_create = selinux_inode_create, 5415 .inode_link = selinux_inode_link, 5416 .inode_unlink = selinux_inode_unlink, 5417 .inode_symlink = selinux_inode_symlink, 5418 .inode_mkdir = selinux_inode_mkdir, 5419 .inode_rmdir = selinux_inode_rmdir, 5420 .inode_mknod = selinux_inode_mknod, 5421 .inode_rename = selinux_inode_rename, 5422 .inode_readlink = selinux_inode_readlink, 5423 .inode_follow_link = selinux_inode_follow_link, 5424 .inode_permission = selinux_inode_permission, 5425 .inode_setattr = selinux_inode_setattr, 5426 .inode_getattr = selinux_inode_getattr, 5427 .inode_setxattr = selinux_inode_setxattr, 5428 .inode_post_setxattr = selinux_inode_post_setxattr, 5429 .inode_getxattr = selinux_inode_getxattr, 5430 .inode_listxattr = selinux_inode_listxattr, 5431 .inode_removexattr = selinux_inode_removexattr, 5432 .inode_getsecurity = selinux_inode_getsecurity, 5433 .inode_setsecurity = selinux_inode_setsecurity, 5434 .inode_listsecurity = selinux_inode_listsecurity, 5435 .inode_need_killpriv = selinux_inode_need_killpriv, 5436 .inode_killpriv = selinux_inode_killpriv, 5437 .inode_getsecid = selinux_inode_getsecid, 5438 5439 .file_permission = selinux_file_permission, 5440 .file_alloc_security = selinux_file_alloc_security, 5441 .file_free_security = selinux_file_free_security, 5442 .file_ioctl = selinux_file_ioctl, 5443 .file_mmap = selinux_file_mmap, 5444 .file_mprotect = selinux_file_mprotect, 5445 .file_lock = selinux_file_lock, 5446 .file_fcntl = selinux_file_fcntl, 5447 .file_set_fowner = selinux_file_set_fowner, 5448 .file_send_sigiotask = selinux_file_send_sigiotask, 5449 .file_receive = selinux_file_receive, 5450 5451 .dentry_open = selinux_dentry_open, 5452 5453 .task_create = selinux_task_create, 5454 .task_alloc_security = selinux_task_alloc_security, 5455 .task_free_security = selinux_task_free_security, 5456 .task_setuid = selinux_task_setuid, 5457 .task_post_setuid = selinux_task_post_setuid, 5458 .task_setgid = selinux_task_setgid, 5459 .task_setpgid = selinux_task_setpgid, 5460 .task_getpgid = selinux_task_getpgid, 5461 .task_getsid = selinux_task_getsid, 5462 .task_getsecid = selinux_task_getsecid, 5463 .task_setgroups = selinux_task_setgroups, 5464 .task_setnice = selinux_task_setnice, 5465 .task_setioprio = selinux_task_setioprio, 5466 .task_getioprio = selinux_task_getioprio, 5467 .task_setrlimit = selinux_task_setrlimit, 5468 .task_setscheduler = selinux_task_setscheduler, 5469 .task_getscheduler = selinux_task_getscheduler, 5470 .task_movememory = selinux_task_movememory, 5471 .task_kill = selinux_task_kill, 5472 .task_wait = selinux_task_wait, 5473 .task_prctl = selinux_task_prctl, 5474 .task_reparent_to_init = selinux_task_reparent_to_init, 5475 .task_to_inode = selinux_task_to_inode, 5476 5477 .ipc_permission = selinux_ipc_permission, 5478 .ipc_getsecid = selinux_ipc_getsecid, 5479 5480 .msg_msg_alloc_security = selinux_msg_msg_alloc_security, 5481 .msg_msg_free_security = selinux_msg_msg_free_security, 5482 5483 .msg_queue_alloc_security = selinux_msg_queue_alloc_security, 5484 .msg_queue_free_security = selinux_msg_queue_free_security, 5485 .msg_queue_associate = selinux_msg_queue_associate, 5486 .msg_queue_msgctl = selinux_msg_queue_msgctl, 5487 .msg_queue_msgsnd = selinux_msg_queue_msgsnd, 5488 .msg_queue_msgrcv = selinux_msg_queue_msgrcv, 5489 5490 .shm_alloc_security = selinux_shm_alloc_security, 5491 .shm_free_security = selinux_shm_free_security, 5492 .shm_associate = selinux_shm_associate, 5493 .shm_shmctl = selinux_shm_shmctl, 5494 .shm_shmat = selinux_shm_shmat, 5495 5496 .sem_alloc_security = selinux_sem_alloc_security, 5497 .sem_free_security = selinux_sem_free_security, 5498 .sem_associate = selinux_sem_associate, 5499 .sem_semctl = selinux_sem_semctl, 5500 .sem_semop = selinux_sem_semop, 5501 5502 .d_instantiate = selinux_d_instantiate, 5503 5504 .getprocattr = selinux_getprocattr, 5505 .setprocattr = selinux_setprocattr, 5506 5507 .secid_to_secctx = selinux_secid_to_secctx, 5508 .secctx_to_secid = selinux_secctx_to_secid, 5509 .release_secctx = selinux_release_secctx, 5510 5511 .unix_stream_connect = selinux_socket_unix_stream_connect, 5512 .unix_may_send = selinux_socket_unix_may_send, 5513 5514 .socket_create = selinux_socket_create, 5515 .socket_post_create = selinux_socket_post_create, 5516 .socket_bind = selinux_socket_bind, 5517 .socket_connect = selinux_socket_connect, 5518 .socket_listen = selinux_socket_listen, 5519 .socket_accept = selinux_socket_accept, 5520 .socket_sendmsg = selinux_socket_sendmsg, 5521 .socket_recvmsg = selinux_socket_recvmsg, 5522 .socket_getsockname = selinux_socket_getsockname, 5523 .socket_getpeername = selinux_socket_getpeername, 5524 .socket_getsockopt = selinux_socket_getsockopt, 5525 .socket_setsockopt = selinux_socket_setsockopt, 5526 .socket_shutdown = selinux_socket_shutdown, 5527 .socket_sock_rcv_skb = selinux_socket_sock_rcv_skb, 5528 .socket_getpeersec_stream = selinux_socket_getpeersec_stream, 5529 .socket_getpeersec_dgram = selinux_socket_getpeersec_dgram, 5530 .sk_alloc_security = selinux_sk_alloc_security, 5531 .sk_free_security = selinux_sk_free_security, 5532 .sk_clone_security = selinux_sk_clone_security, 5533 .sk_getsecid = selinux_sk_getsecid, 5534 .sock_graft = selinux_sock_graft, 5535 .inet_conn_request = selinux_inet_conn_request, 5536 .inet_csk_clone = selinux_inet_csk_clone, 5537 .inet_conn_established = selinux_inet_conn_established, 5538 .req_classify_flow = selinux_req_classify_flow, 5539 5540 #ifdef CONFIG_SECURITY_NETWORK_XFRM 5541 .xfrm_policy_alloc_security = selinux_xfrm_policy_alloc, 5542 .xfrm_policy_clone_security = selinux_xfrm_policy_clone, 5543 .xfrm_policy_free_security = selinux_xfrm_policy_free, 5544 .xfrm_policy_delete_security = selinux_xfrm_policy_delete, 5545 .xfrm_state_alloc_security = selinux_xfrm_state_alloc, 5546 .xfrm_state_free_security = selinux_xfrm_state_free, 5547 .xfrm_state_delete_security = selinux_xfrm_state_delete, 5548 .xfrm_policy_lookup = selinux_xfrm_policy_lookup, 5549 .xfrm_state_pol_flow_match = selinux_xfrm_state_pol_flow_match, 5550 .xfrm_decode_session = selinux_xfrm_decode_session, 5551 #endif 5552 5553 #ifdef CONFIG_KEYS 5554 .key_alloc = selinux_key_alloc, 5555 .key_free = selinux_key_free, 5556 .key_permission = selinux_key_permission, 5557 .key_getsecurity = selinux_key_getsecurity, 5558 #endif 5559 5560 #ifdef CONFIG_AUDIT 5561 .audit_rule_init = selinux_audit_rule_init, 5562 .audit_rule_known = selinux_audit_rule_known, 5563 .audit_rule_match = selinux_audit_rule_match, 5564 .audit_rule_free = selinux_audit_rule_free, 5565 #endif 5566 }; 5567 5568 static __init int selinux_init(void) 5569 { 5570 struct task_security_struct *tsec; 5571 5572 if (!security_module_enable(&selinux_ops)) { 5573 selinux_enabled = 0; 5574 return 0; 5575 } 5576 5577 if (!selinux_enabled) { 5578 printk(KERN_INFO "SELinux: Disabled at boot.\n"); 5579 return 0; 5580 } 5581 5582 printk(KERN_INFO "SELinux: Initializing.\n"); 5583 5584 /* Set the security state for the initial task. */ 5585 if (task_alloc_security(current)) 5586 panic("SELinux: Failed to initialize initial task.\n"); 5587 tsec = current->security; 5588 tsec->osid = tsec->sid = SECINITSID_KERNEL; 5589 5590 sel_inode_cache = kmem_cache_create("selinux_inode_security", 5591 sizeof(struct inode_security_struct), 5592 0, SLAB_PANIC, NULL); 5593 avc_init(); 5594 5595 secondary_ops = security_ops; 5596 if (!secondary_ops) 5597 panic("SELinux: No initial security operations\n"); 5598 if (register_security(&selinux_ops)) 5599 panic("SELinux: Unable to register with kernel.\n"); 5600 5601 if (selinux_enforcing) 5602 printk(KERN_DEBUG "SELinux: Starting in enforcing mode\n"); 5603 else 5604 printk(KERN_DEBUG "SELinux: Starting in permissive mode\n"); 5605 5606 return 0; 5607 } 5608 5609 void selinux_complete_init(void) 5610 { 5611 printk(KERN_DEBUG "SELinux: Completing initialization.\n"); 5612 5613 /* Set up any superblocks initialized prior to the policy load. */ 5614 printk(KERN_DEBUG "SELinux: Setting up existing superblocks.\n"); 5615 spin_lock(&sb_lock); 5616 spin_lock(&sb_security_lock); 5617 next_sb: 5618 if (!list_empty(&superblock_security_head)) { 5619 struct superblock_security_struct *sbsec = 5620 list_entry(superblock_security_head.next, 5621 struct superblock_security_struct, 5622 list); 5623 struct super_block *sb = sbsec->sb; 5624 sb->s_count++; 5625 spin_unlock(&sb_security_lock); 5626 spin_unlock(&sb_lock); 5627 down_read(&sb->s_umount); 5628 if (sb->s_root) 5629 superblock_doinit(sb, NULL); 5630 drop_super(sb); 5631 spin_lock(&sb_lock); 5632 spin_lock(&sb_security_lock); 5633 list_del_init(&sbsec->list); 5634 goto next_sb; 5635 } 5636 spin_unlock(&sb_security_lock); 5637 spin_unlock(&sb_lock); 5638 } 5639 5640 /* SELinux requires early initialization in order to label 5641 all processes and objects when they are created. */ 5642 security_initcall(selinux_init); 5643 5644 #if defined(CONFIG_NETFILTER) 5645 5646 static struct nf_hook_ops selinux_ipv4_ops[] = { 5647 { 5648 .hook = selinux_ipv4_postroute, 5649 .owner = THIS_MODULE, 5650 .pf = PF_INET, 5651 .hooknum = NF_INET_POST_ROUTING, 5652 .priority = NF_IP_PRI_SELINUX_LAST, 5653 }, 5654 { 5655 .hook = selinux_ipv4_forward, 5656 .owner = THIS_MODULE, 5657 .pf = PF_INET, 5658 .hooknum = NF_INET_FORWARD, 5659 .priority = NF_IP_PRI_SELINUX_FIRST, 5660 } 5661 }; 5662 5663 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE) 5664 5665 static struct nf_hook_ops selinux_ipv6_ops[] = { 5666 { 5667 .hook = selinux_ipv6_postroute, 5668 .owner = THIS_MODULE, 5669 .pf = PF_INET6, 5670 .hooknum = NF_INET_POST_ROUTING, 5671 .priority = NF_IP6_PRI_SELINUX_LAST, 5672 }, 5673 { 5674 .hook = selinux_ipv6_forward, 5675 .owner = THIS_MODULE, 5676 .pf = PF_INET6, 5677 .hooknum = NF_INET_FORWARD, 5678 .priority = NF_IP6_PRI_SELINUX_FIRST, 5679 } 5680 }; 5681 5682 #endif /* IPV6 */ 5683 5684 static int __init selinux_nf_ip_init(void) 5685 { 5686 int err = 0; 5687 5688 if (!selinux_enabled) 5689 goto out; 5690 5691 printk(KERN_DEBUG "SELinux: Registering netfilter hooks\n"); 5692 5693 err = nf_register_hooks(selinux_ipv4_ops, ARRAY_SIZE(selinux_ipv4_ops)); 5694 if (err) 5695 panic("SELinux: nf_register_hooks for IPv4: error %d\n", err); 5696 5697 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE) 5698 err = nf_register_hooks(selinux_ipv6_ops, ARRAY_SIZE(selinux_ipv6_ops)); 5699 if (err) 5700 panic("SELinux: nf_register_hooks for IPv6: error %d\n", err); 5701 #endif /* IPV6 */ 5702 5703 out: 5704 return err; 5705 } 5706 5707 __initcall(selinux_nf_ip_init); 5708 5709 #ifdef CONFIG_SECURITY_SELINUX_DISABLE 5710 static void selinux_nf_ip_exit(void) 5711 { 5712 printk(KERN_DEBUG "SELinux: Unregistering netfilter hooks\n"); 5713 5714 nf_unregister_hooks(selinux_ipv4_ops, ARRAY_SIZE(selinux_ipv4_ops)); 5715 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE) 5716 nf_unregister_hooks(selinux_ipv6_ops, ARRAY_SIZE(selinux_ipv6_ops)); 5717 #endif /* IPV6 */ 5718 } 5719 #endif 5720 5721 #else /* CONFIG_NETFILTER */ 5722 5723 #ifdef CONFIG_SECURITY_SELINUX_DISABLE 5724 #define selinux_nf_ip_exit() 5725 #endif 5726 5727 #endif /* CONFIG_NETFILTER */ 5728 5729 #ifdef CONFIG_SECURITY_SELINUX_DISABLE 5730 static int selinux_disabled; 5731 5732 int selinux_disable(void) 5733 { 5734 extern void exit_sel_fs(void); 5735 5736 if (ss_initialized) { 5737 /* Not permitted after initial policy load. */ 5738 return -EINVAL; 5739 } 5740 5741 if (selinux_disabled) { 5742 /* Only do this once. */ 5743 return -EINVAL; 5744 } 5745 5746 printk(KERN_INFO "SELinux: Disabled at runtime.\n"); 5747 5748 selinux_disabled = 1; 5749 selinux_enabled = 0; 5750 5751 /* Reset security_ops to the secondary module, dummy or capability. */ 5752 security_ops = secondary_ops; 5753 5754 /* Unregister netfilter hooks. */ 5755 selinux_nf_ip_exit(); 5756 5757 /* Unregister selinuxfs. */ 5758 exit_sel_fs(); 5759 5760 return 0; 5761 } 5762 #endif 5763