1 /* 2 * NSA Security-Enhanced Linux (SELinux) security module 3 * 4 * This file contains the SELinux hook function implementations. 5 * 6 * Authors: Stephen Smalley, <sds@epoch.ncsc.mil> 7 * Chris Vance, <cvance@nai.com> 8 * Wayne Salamon, <wsalamon@nai.com> 9 * James Morris <jmorris@redhat.com> 10 * 11 * Copyright (C) 2001,2002 Networks Associates Technology, Inc. 12 * Copyright (C) 2003-2008 Red Hat, Inc., James Morris <jmorris@redhat.com> 13 * Eric Paris <eparis@redhat.com> 14 * Copyright (C) 2004-2005 Trusted Computer Solutions, Inc. 15 * <dgoeddel@trustedcs.com> 16 * Copyright (C) 2006, 2007 Hewlett-Packard Development Company, L.P. 17 * Paul Moore <paul.moore@hp.com> 18 * Copyright (C) 2007 Hitachi Software Engineering Co., Ltd. 19 * Yuichi Nakamura <ynakam@hitachisoft.jp> 20 * 21 * This program is free software; you can redistribute it and/or modify 22 * it under the terms of the GNU General Public License version 2, 23 * as published by the Free Software Foundation. 24 */ 25 26 #include <linux/init.h> 27 #include <linux/kernel.h> 28 #include <linux/tracehook.h> 29 #include <linux/errno.h> 30 #include <linux/sched.h> 31 #include <linux/security.h> 32 #include <linux/xattr.h> 33 #include <linux/capability.h> 34 #include <linux/unistd.h> 35 #include <linux/mm.h> 36 #include <linux/mman.h> 37 #include <linux/slab.h> 38 #include <linux/pagemap.h> 39 #include <linux/swap.h> 40 #include <linux/spinlock.h> 41 #include <linux/syscalls.h> 42 #include <linux/file.h> 43 #include <linux/fdtable.h> 44 #include <linux/namei.h> 45 #include <linux/mount.h> 46 #include <linux/proc_fs.h> 47 #include <linux/netfilter_ipv4.h> 48 #include <linux/netfilter_ipv6.h> 49 #include <linux/tty.h> 50 #include <net/icmp.h> 51 #include <net/ip.h> /* for local_port_range[] */ 52 #include <net/tcp.h> /* struct or_callable used in sock_rcv_skb */ 53 #include <net/net_namespace.h> 54 #include <net/netlabel.h> 55 #include <linux/uaccess.h> 56 #include <asm/ioctls.h> 57 #include <asm/atomic.h> 58 #include <linux/bitops.h> 59 #include <linux/interrupt.h> 60 #include <linux/netdevice.h> /* for network interface checks */ 61 #include <linux/netlink.h> 62 #include <linux/tcp.h> 63 #include <linux/udp.h> 64 #include <linux/dccp.h> 65 #include <linux/quota.h> 66 #include <linux/un.h> /* for Unix socket types */ 67 #include <net/af_unix.h> /* for Unix socket types */ 68 #include <linux/parser.h> 69 #include <linux/nfs_mount.h> 70 #include <net/ipv6.h> 71 #include <linux/hugetlb.h> 72 #include <linux/personality.h> 73 #include <linux/sysctl.h> 74 #include <linux/audit.h> 75 #include <linux/string.h> 76 #include <linux/selinux.h> 77 #include <linux/mutex.h> 78 #include <linux/posix-timers.h> 79 80 #include "avc.h" 81 #include "objsec.h" 82 #include "netif.h" 83 #include "netnode.h" 84 #include "netport.h" 85 #include "xfrm.h" 86 #include "netlabel.h" 87 #include "audit.h" 88 89 #define XATTR_SELINUX_SUFFIX "selinux" 90 #define XATTR_NAME_SELINUX XATTR_SECURITY_PREFIX XATTR_SELINUX_SUFFIX 91 92 #define NUM_SEL_MNT_OPTS 4 93 94 extern unsigned int policydb_loaded_version; 95 extern int selinux_nlmsg_lookup(u16 sclass, u16 nlmsg_type, u32 *perm); 96 extern int selinux_compat_net; 97 extern struct security_operations *security_ops; 98 99 /* SECMARK reference count */ 100 atomic_t selinux_secmark_refcount = ATOMIC_INIT(0); 101 102 #ifdef CONFIG_SECURITY_SELINUX_DEVELOP 103 int selinux_enforcing; 104 105 static int __init enforcing_setup(char *str) 106 { 107 unsigned long enforcing; 108 if (!strict_strtoul(str, 0, &enforcing)) 109 selinux_enforcing = enforcing ? 1 : 0; 110 return 1; 111 } 112 __setup("enforcing=", enforcing_setup); 113 #endif 114 115 #ifdef CONFIG_SECURITY_SELINUX_BOOTPARAM 116 int selinux_enabled = CONFIG_SECURITY_SELINUX_BOOTPARAM_VALUE; 117 118 static int __init selinux_enabled_setup(char *str) 119 { 120 unsigned long enabled; 121 if (!strict_strtoul(str, 0, &enabled)) 122 selinux_enabled = enabled ? 1 : 0; 123 return 1; 124 } 125 __setup("selinux=", selinux_enabled_setup); 126 #else 127 int selinux_enabled = 1; 128 #endif 129 130 131 /* 132 * Minimal support for a secondary security module, 133 * just to allow the use of the capability module. 134 */ 135 static struct security_operations *secondary_ops; 136 137 /* Lists of inode and superblock security structures initialized 138 before the policy was loaded. */ 139 static LIST_HEAD(superblock_security_head); 140 static DEFINE_SPINLOCK(sb_security_lock); 141 142 static struct kmem_cache *sel_inode_cache; 143 144 /** 145 * selinux_secmark_enabled - Check to see if SECMARK is currently enabled 146 * 147 * Description: 148 * This function checks the SECMARK reference counter to see if any SECMARK 149 * targets are currently configured, if the reference counter is greater than 150 * zero SECMARK is considered to be enabled. Returns true (1) if SECMARK is 151 * enabled, false (0) if SECMARK is disabled. 152 * 153 */ 154 static int selinux_secmark_enabled(void) 155 { 156 return (atomic_read(&selinux_secmark_refcount) > 0); 157 } 158 159 /* Allocate and free functions for each kind of security blob. */ 160 161 static int task_alloc_security(struct task_struct *task) 162 { 163 struct task_security_struct *tsec; 164 165 tsec = kzalloc(sizeof(struct task_security_struct), GFP_KERNEL); 166 if (!tsec) 167 return -ENOMEM; 168 169 tsec->osid = tsec->sid = SECINITSID_UNLABELED; 170 task->cred->security = tsec; 171 172 return 0; 173 } 174 175 static void task_free_security(struct task_struct *task) 176 { 177 struct task_security_struct *tsec = task->cred->security; 178 task->cred->security = NULL; 179 kfree(tsec); 180 } 181 182 static int inode_alloc_security(struct inode *inode) 183 { 184 struct task_security_struct *tsec = current->cred->security; 185 struct inode_security_struct *isec; 186 187 isec = kmem_cache_zalloc(sel_inode_cache, GFP_NOFS); 188 if (!isec) 189 return -ENOMEM; 190 191 mutex_init(&isec->lock); 192 INIT_LIST_HEAD(&isec->list); 193 isec->inode = inode; 194 isec->sid = SECINITSID_UNLABELED; 195 isec->sclass = SECCLASS_FILE; 196 isec->task_sid = tsec->sid; 197 inode->i_security = isec; 198 199 return 0; 200 } 201 202 static void inode_free_security(struct inode *inode) 203 { 204 struct inode_security_struct *isec = inode->i_security; 205 struct superblock_security_struct *sbsec = inode->i_sb->s_security; 206 207 spin_lock(&sbsec->isec_lock); 208 if (!list_empty(&isec->list)) 209 list_del_init(&isec->list); 210 spin_unlock(&sbsec->isec_lock); 211 212 inode->i_security = NULL; 213 kmem_cache_free(sel_inode_cache, isec); 214 } 215 216 static int file_alloc_security(struct file *file) 217 { 218 struct task_security_struct *tsec = current->cred->security; 219 struct file_security_struct *fsec; 220 221 fsec = kzalloc(sizeof(struct file_security_struct), GFP_KERNEL); 222 if (!fsec) 223 return -ENOMEM; 224 225 fsec->sid = tsec->sid; 226 fsec->fown_sid = tsec->sid; 227 file->f_security = fsec; 228 229 return 0; 230 } 231 232 static void file_free_security(struct file *file) 233 { 234 struct file_security_struct *fsec = file->f_security; 235 file->f_security = NULL; 236 kfree(fsec); 237 } 238 239 static int superblock_alloc_security(struct super_block *sb) 240 { 241 struct superblock_security_struct *sbsec; 242 243 sbsec = kzalloc(sizeof(struct superblock_security_struct), GFP_KERNEL); 244 if (!sbsec) 245 return -ENOMEM; 246 247 mutex_init(&sbsec->lock); 248 INIT_LIST_HEAD(&sbsec->list); 249 INIT_LIST_HEAD(&sbsec->isec_head); 250 spin_lock_init(&sbsec->isec_lock); 251 sbsec->sb = sb; 252 sbsec->sid = SECINITSID_UNLABELED; 253 sbsec->def_sid = SECINITSID_FILE; 254 sbsec->mntpoint_sid = SECINITSID_UNLABELED; 255 sb->s_security = sbsec; 256 257 return 0; 258 } 259 260 static void superblock_free_security(struct super_block *sb) 261 { 262 struct superblock_security_struct *sbsec = sb->s_security; 263 264 spin_lock(&sb_security_lock); 265 if (!list_empty(&sbsec->list)) 266 list_del_init(&sbsec->list); 267 spin_unlock(&sb_security_lock); 268 269 sb->s_security = NULL; 270 kfree(sbsec); 271 } 272 273 static int sk_alloc_security(struct sock *sk, int family, gfp_t priority) 274 { 275 struct sk_security_struct *ssec; 276 277 ssec = kzalloc(sizeof(*ssec), priority); 278 if (!ssec) 279 return -ENOMEM; 280 281 ssec->peer_sid = SECINITSID_UNLABELED; 282 ssec->sid = SECINITSID_UNLABELED; 283 sk->sk_security = ssec; 284 285 selinux_netlbl_sk_security_reset(ssec, family); 286 287 return 0; 288 } 289 290 static void sk_free_security(struct sock *sk) 291 { 292 struct sk_security_struct *ssec = sk->sk_security; 293 294 sk->sk_security = NULL; 295 selinux_netlbl_sk_security_free(ssec); 296 kfree(ssec); 297 } 298 299 /* The security server must be initialized before 300 any labeling or access decisions can be provided. */ 301 extern int ss_initialized; 302 303 /* The file system's label must be initialized prior to use. */ 304 305 static char *labeling_behaviors[6] = { 306 "uses xattr", 307 "uses transition SIDs", 308 "uses task SIDs", 309 "uses genfs_contexts", 310 "not configured for labeling", 311 "uses mountpoint labeling", 312 }; 313 314 static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dentry); 315 316 static inline int inode_doinit(struct inode *inode) 317 { 318 return inode_doinit_with_dentry(inode, NULL); 319 } 320 321 enum { 322 Opt_error = -1, 323 Opt_context = 1, 324 Opt_fscontext = 2, 325 Opt_defcontext = 3, 326 Opt_rootcontext = 4, 327 }; 328 329 static const match_table_t tokens = { 330 {Opt_context, CONTEXT_STR "%s"}, 331 {Opt_fscontext, FSCONTEXT_STR "%s"}, 332 {Opt_defcontext, DEFCONTEXT_STR "%s"}, 333 {Opt_rootcontext, ROOTCONTEXT_STR "%s"}, 334 {Opt_error, NULL}, 335 }; 336 337 #define SEL_MOUNT_FAIL_MSG "SELinux: duplicate or incompatible mount options\n" 338 339 static int may_context_mount_sb_relabel(u32 sid, 340 struct superblock_security_struct *sbsec, 341 struct task_security_struct *tsec) 342 { 343 int rc; 344 345 rc = avc_has_perm(tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM, 346 FILESYSTEM__RELABELFROM, NULL); 347 if (rc) 348 return rc; 349 350 rc = avc_has_perm(tsec->sid, sid, SECCLASS_FILESYSTEM, 351 FILESYSTEM__RELABELTO, NULL); 352 return rc; 353 } 354 355 static int may_context_mount_inode_relabel(u32 sid, 356 struct superblock_security_struct *sbsec, 357 struct task_security_struct *tsec) 358 { 359 int rc; 360 rc = avc_has_perm(tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM, 361 FILESYSTEM__RELABELFROM, NULL); 362 if (rc) 363 return rc; 364 365 rc = avc_has_perm(sid, sbsec->sid, SECCLASS_FILESYSTEM, 366 FILESYSTEM__ASSOCIATE, NULL); 367 return rc; 368 } 369 370 static int sb_finish_set_opts(struct super_block *sb) 371 { 372 struct superblock_security_struct *sbsec = sb->s_security; 373 struct dentry *root = sb->s_root; 374 struct inode *root_inode = root->d_inode; 375 int rc = 0; 376 377 if (sbsec->behavior == SECURITY_FS_USE_XATTR) { 378 /* Make sure that the xattr handler exists and that no 379 error other than -ENODATA is returned by getxattr on 380 the root directory. -ENODATA is ok, as this may be 381 the first boot of the SELinux kernel before we have 382 assigned xattr values to the filesystem. */ 383 if (!root_inode->i_op->getxattr) { 384 printk(KERN_WARNING "SELinux: (dev %s, type %s) has no " 385 "xattr support\n", sb->s_id, sb->s_type->name); 386 rc = -EOPNOTSUPP; 387 goto out; 388 } 389 rc = root_inode->i_op->getxattr(root, XATTR_NAME_SELINUX, NULL, 0); 390 if (rc < 0 && rc != -ENODATA) { 391 if (rc == -EOPNOTSUPP) 392 printk(KERN_WARNING "SELinux: (dev %s, type " 393 "%s) has no security xattr handler\n", 394 sb->s_id, sb->s_type->name); 395 else 396 printk(KERN_WARNING "SELinux: (dev %s, type " 397 "%s) getxattr errno %d\n", sb->s_id, 398 sb->s_type->name, -rc); 399 goto out; 400 } 401 } 402 403 sbsec->initialized = 1; 404 405 if (sbsec->behavior > ARRAY_SIZE(labeling_behaviors)) 406 printk(KERN_ERR "SELinux: initialized (dev %s, type %s), unknown behavior\n", 407 sb->s_id, sb->s_type->name); 408 else 409 printk(KERN_DEBUG "SELinux: initialized (dev %s, type %s), %s\n", 410 sb->s_id, sb->s_type->name, 411 labeling_behaviors[sbsec->behavior-1]); 412 413 /* Initialize the root inode. */ 414 rc = inode_doinit_with_dentry(root_inode, root); 415 416 /* Initialize any other inodes associated with the superblock, e.g. 417 inodes created prior to initial policy load or inodes created 418 during get_sb by a pseudo filesystem that directly 419 populates itself. */ 420 spin_lock(&sbsec->isec_lock); 421 next_inode: 422 if (!list_empty(&sbsec->isec_head)) { 423 struct inode_security_struct *isec = 424 list_entry(sbsec->isec_head.next, 425 struct inode_security_struct, list); 426 struct inode *inode = isec->inode; 427 spin_unlock(&sbsec->isec_lock); 428 inode = igrab(inode); 429 if (inode) { 430 if (!IS_PRIVATE(inode)) 431 inode_doinit(inode); 432 iput(inode); 433 } 434 spin_lock(&sbsec->isec_lock); 435 list_del_init(&isec->list); 436 goto next_inode; 437 } 438 spin_unlock(&sbsec->isec_lock); 439 out: 440 return rc; 441 } 442 443 /* 444 * This function should allow an FS to ask what it's mount security 445 * options were so it can use those later for submounts, displaying 446 * mount options, or whatever. 447 */ 448 static int selinux_get_mnt_opts(const struct super_block *sb, 449 struct security_mnt_opts *opts) 450 { 451 int rc = 0, i; 452 struct superblock_security_struct *sbsec = sb->s_security; 453 char *context = NULL; 454 u32 len; 455 char tmp; 456 457 security_init_mnt_opts(opts); 458 459 if (!sbsec->initialized) 460 return -EINVAL; 461 462 if (!ss_initialized) 463 return -EINVAL; 464 465 /* 466 * if we ever use sbsec flags for anything other than tracking mount 467 * settings this is going to need a mask 468 */ 469 tmp = sbsec->flags; 470 /* count the number of mount options for this sb */ 471 for (i = 0; i < 8; i++) { 472 if (tmp & 0x01) 473 opts->num_mnt_opts++; 474 tmp >>= 1; 475 } 476 477 opts->mnt_opts = kcalloc(opts->num_mnt_opts, sizeof(char *), GFP_ATOMIC); 478 if (!opts->mnt_opts) { 479 rc = -ENOMEM; 480 goto out_free; 481 } 482 483 opts->mnt_opts_flags = kcalloc(opts->num_mnt_opts, sizeof(int), GFP_ATOMIC); 484 if (!opts->mnt_opts_flags) { 485 rc = -ENOMEM; 486 goto out_free; 487 } 488 489 i = 0; 490 if (sbsec->flags & FSCONTEXT_MNT) { 491 rc = security_sid_to_context(sbsec->sid, &context, &len); 492 if (rc) 493 goto out_free; 494 opts->mnt_opts[i] = context; 495 opts->mnt_opts_flags[i++] = FSCONTEXT_MNT; 496 } 497 if (sbsec->flags & CONTEXT_MNT) { 498 rc = security_sid_to_context(sbsec->mntpoint_sid, &context, &len); 499 if (rc) 500 goto out_free; 501 opts->mnt_opts[i] = context; 502 opts->mnt_opts_flags[i++] = CONTEXT_MNT; 503 } 504 if (sbsec->flags & DEFCONTEXT_MNT) { 505 rc = security_sid_to_context(sbsec->def_sid, &context, &len); 506 if (rc) 507 goto out_free; 508 opts->mnt_opts[i] = context; 509 opts->mnt_opts_flags[i++] = DEFCONTEXT_MNT; 510 } 511 if (sbsec->flags & ROOTCONTEXT_MNT) { 512 struct inode *root = sbsec->sb->s_root->d_inode; 513 struct inode_security_struct *isec = root->i_security; 514 515 rc = security_sid_to_context(isec->sid, &context, &len); 516 if (rc) 517 goto out_free; 518 opts->mnt_opts[i] = context; 519 opts->mnt_opts_flags[i++] = ROOTCONTEXT_MNT; 520 } 521 522 BUG_ON(i != opts->num_mnt_opts); 523 524 return 0; 525 526 out_free: 527 security_free_mnt_opts(opts); 528 return rc; 529 } 530 531 static int bad_option(struct superblock_security_struct *sbsec, char flag, 532 u32 old_sid, u32 new_sid) 533 { 534 /* check if the old mount command had the same options */ 535 if (sbsec->initialized) 536 if (!(sbsec->flags & flag) || 537 (old_sid != new_sid)) 538 return 1; 539 540 /* check if we were passed the same options twice, 541 * aka someone passed context=a,context=b 542 */ 543 if (!sbsec->initialized) 544 if (sbsec->flags & flag) 545 return 1; 546 return 0; 547 } 548 549 /* 550 * Allow filesystems with binary mount data to explicitly set mount point 551 * labeling information. 552 */ 553 static int selinux_set_mnt_opts(struct super_block *sb, 554 struct security_mnt_opts *opts) 555 { 556 int rc = 0, i; 557 struct task_security_struct *tsec = current->cred->security; 558 struct superblock_security_struct *sbsec = sb->s_security; 559 const char *name = sb->s_type->name; 560 struct inode *inode = sbsec->sb->s_root->d_inode; 561 struct inode_security_struct *root_isec = inode->i_security; 562 u32 fscontext_sid = 0, context_sid = 0, rootcontext_sid = 0; 563 u32 defcontext_sid = 0; 564 char **mount_options = opts->mnt_opts; 565 int *flags = opts->mnt_opts_flags; 566 int num_opts = opts->num_mnt_opts; 567 568 mutex_lock(&sbsec->lock); 569 570 if (!ss_initialized) { 571 if (!num_opts) { 572 /* Defer initialization until selinux_complete_init, 573 after the initial policy is loaded and the security 574 server is ready to handle calls. */ 575 spin_lock(&sb_security_lock); 576 if (list_empty(&sbsec->list)) 577 list_add(&sbsec->list, &superblock_security_head); 578 spin_unlock(&sb_security_lock); 579 goto out; 580 } 581 rc = -EINVAL; 582 printk(KERN_WARNING "SELinux: Unable to set superblock options " 583 "before the security server is initialized\n"); 584 goto out; 585 } 586 587 /* 588 * Binary mount data FS will come through this function twice. Once 589 * from an explicit call and once from the generic calls from the vfs. 590 * Since the generic VFS calls will not contain any security mount data 591 * we need to skip the double mount verification. 592 * 593 * This does open a hole in which we will not notice if the first 594 * mount using this sb set explict options and a second mount using 595 * this sb does not set any security options. (The first options 596 * will be used for both mounts) 597 */ 598 if (sbsec->initialized && (sb->s_type->fs_flags & FS_BINARY_MOUNTDATA) 599 && (num_opts == 0)) 600 goto out; 601 602 /* 603 * parse the mount options, check if they are valid sids. 604 * also check if someone is trying to mount the same sb more 605 * than once with different security options. 606 */ 607 for (i = 0; i < num_opts; i++) { 608 u32 sid; 609 rc = security_context_to_sid(mount_options[i], 610 strlen(mount_options[i]), &sid); 611 if (rc) { 612 printk(KERN_WARNING "SELinux: security_context_to_sid" 613 "(%s) failed for (dev %s, type %s) errno=%d\n", 614 mount_options[i], sb->s_id, name, rc); 615 goto out; 616 } 617 switch (flags[i]) { 618 case FSCONTEXT_MNT: 619 fscontext_sid = sid; 620 621 if (bad_option(sbsec, FSCONTEXT_MNT, sbsec->sid, 622 fscontext_sid)) 623 goto out_double_mount; 624 625 sbsec->flags |= FSCONTEXT_MNT; 626 break; 627 case CONTEXT_MNT: 628 context_sid = sid; 629 630 if (bad_option(sbsec, CONTEXT_MNT, sbsec->mntpoint_sid, 631 context_sid)) 632 goto out_double_mount; 633 634 sbsec->flags |= CONTEXT_MNT; 635 break; 636 case ROOTCONTEXT_MNT: 637 rootcontext_sid = sid; 638 639 if (bad_option(sbsec, ROOTCONTEXT_MNT, root_isec->sid, 640 rootcontext_sid)) 641 goto out_double_mount; 642 643 sbsec->flags |= ROOTCONTEXT_MNT; 644 645 break; 646 case DEFCONTEXT_MNT: 647 defcontext_sid = sid; 648 649 if (bad_option(sbsec, DEFCONTEXT_MNT, sbsec->def_sid, 650 defcontext_sid)) 651 goto out_double_mount; 652 653 sbsec->flags |= DEFCONTEXT_MNT; 654 655 break; 656 default: 657 rc = -EINVAL; 658 goto out; 659 } 660 } 661 662 if (sbsec->initialized) { 663 /* previously mounted with options, but not on this attempt? */ 664 if (sbsec->flags && !num_opts) 665 goto out_double_mount; 666 rc = 0; 667 goto out; 668 } 669 670 if (strcmp(sb->s_type->name, "proc") == 0) 671 sbsec->proc = 1; 672 673 /* Determine the labeling behavior to use for this filesystem type. */ 674 rc = security_fs_use(sb->s_type->name, &sbsec->behavior, &sbsec->sid); 675 if (rc) { 676 printk(KERN_WARNING "%s: security_fs_use(%s) returned %d\n", 677 __func__, sb->s_type->name, rc); 678 goto out; 679 } 680 681 /* sets the context of the superblock for the fs being mounted. */ 682 if (fscontext_sid) { 683 684 rc = may_context_mount_sb_relabel(fscontext_sid, sbsec, tsec); 685 if (rc) 686 goto out; 687 688 sbsec->sid = fscontext_sid; 689 } 690 691 /* 692 * Switch to using mount point labeling behavior. 693 * sets the label used on all file below the mountpoint, and will set 694 * the superblock context if not already set. 695 */ 696 if (context_sid) { 697 if (!fscontext_sid) { 698 rc = may_context_mount_sb_relabel(context_sid, sbsec, tsec); 699 if (rc) 700 goto out; 701 sbsec->sid = context_sid; 702 } else { 703 rc = may_context_mount_inode_relabel(context_sid, sbsec, tsec); 704 if (rc) 705 goto out; 706 } 707 if (!rootcontext_sid) 708 rootcontext_sid = context_sid; 709 710 sbsec->mntpoint_sid = context_sid; 711 sbsec->behavior = SECURITY_FS_USE_MNTPOINT; 712 } 713 714 if (rootcontext_sid) { 715 rc = may_context_mount_inode_relabel(rootcontext_sid, sbsec, tsec); 716 if (rc) 717 goto out; 718 719 root_isec->sid = rootcontext_sid; 720 root_isec->initialized = 1; 721 } 722 723 if (defcontext_sid) { 724 if (sbsec->behavior != SECURITY_FS_USE_XATTR) { 725 rc = -EINVAL; 726 printk(KERN_WARNING "SELinux: defcontext option is " 727 "invalid for this filesystem type\n"); 728 goto out; 729 } 730 731 if (defcontext_sid != sbsec->def_sid) { 732 rc = may_context_mount_inode_relabel(defcontext_sid, 733 sbsec, tsec); 734 if (rc) 735 goto out; 736 } 737 738 sbsec->def_sid = defcontext_sid; 739 } 740 741 rc = sb_finish_set_opts(sb); 742 out: 743 mutex_unlock(&sbsec->lock); 744 return rc; 745 out_double_mount: 746 rc = -EINVAL; 747 printk(KERN_WARNING "SELinux: mount invalid. Same superblock, different " 748 "security settings for (dev %s, type %s)\n", sb->s_id, name); 749 goto out; 750 } 751 752 static void selinux_sb_clone_mnt_opts(const struct super_block *oldsb, 753 struct super_block *newsb) 754 { 755 const struct superblock_security_struct *oldsbsec = oldsb->s_security; 756 struct superblock_security_struct *newsbsec = newsb->s_security; 757 758 int set_fscontext = (oldsbsec->flags & FSCONTEXT_MNT); 759 int set_context = (oldsbsec->flags & CONTEXT_MNT); 760 int set_rootcontext = (oldsbsec->flags & ROOTCONTEXT_MNT); 761 762 /* 763 * if the parent was able to be mounted it clearly had no special lsm 764 * mount options. thus we can safely put this sb on the list and deal 765 * with it later 766 */ 767 if (!ss_initialized) { 768 spin_lock(&sb_security_lock); 769 if (list_empty(&newsbsec->list)) 770 list_add(&newsbsec->list, &superblock_security_head); 771 spin_unlock(&sb_security_lock); 772 return; 773 } 774 775 /* how can we clone if the old one wasn't set up?? */ 776 BUG_ON(!oldsbsec->initialized); 777 778 /* if fs is reusing a sb, just let its options stand... */ 779 if (newsbsec->initialized) 780 return; 781 782 mutex_lock(&newsbsec->lock); 783 784 newsbsec->flags = oldsbsec->flags; 785 786 newsbsec->sid = oldsbsec->sid; 787 newsbsec->def_sid = oldsbsec->def_sid; 788 newsbsec->behavior = oldsbsec->behavior; 789 790 if (set_context) { 791 u32 sid = oldsbsec->mntpoint_sid; 792 793 if (!set_fscontext) 794 newsbsec->sid = sid; 795 if (!set_rootcontext) { 796 struct inode *newinode = newsb->s_root->d_inode; 797 struct inode_security_struct *newisec = newinode->i_security; 798 newisec->sid = sid; 799 } 800 newsbsec->mntpoint_sid = sid; 801 } 802 if (set_rootcontext) { 803 const struct inode *oldinode = oldsb->s_root->d_inode; 804 const struct inode_security_struct *oldisec = oldinode->i_security; 805 struct inode *newinode = newsb->s_root->d_inode; 806 struct inode_security_struct *newisec = newinode->i_security; 807 808 newisec->sid = oldisec->sid; 809 } 810 811 sb_finish_set_opts(newsb); 812 mutex_unlock(&newsbsec->lock); 813 } 814 815 static int selinux_parse_opts_str(char *options, 816 struct security_mnt_opts *opts) 817 { 818 char *p; 819 char *context = NULL, *defcontext = NULL; 820 char *fscontext = NULL, *rootcontext = NULL; 821 int rc, num_mnt_opts = 0; 822 823 opts->num_mnt_opts = 0; 824 825 /* Standard string-based options. */ 826 while ((p = strsep(&options, "|")) != NULL) { 827 int token; 828 substring_t args[MAX_OPT_ARGS]; 829 830 if (!*p) 831 continue; 832 833 token = match_token(p, tokens, args); 834 835 switch (token) { 836 case Opt_context: 837 if (context || defcontext) { 838 rc = -EINVAL; 839 printk(KERN_WARNING SEL_MOUNT_FAIL_MSG); 840 goto out_err; 841 } 842 context = match_strdup(&args[0]); 843 if (!context) { 844 rc = -ENOMEM; 845 goto out_err; 846 } 847 break; 848 849 case Opt_fscontext: 850 if (fscontext) { 851 rc = -EINVAL; 852 printk(KERN_WARNING SEL_MOUNT_FAIL_MSG); 853 goto out_err; 854 } 855 fscontext = match_strdup(&args[0]); 856 if (!fscontext) { 857 rc = -ENOMEM; 858 goto out_err; 859 } 860 break; 861 862 case Opt_rootcontext: 863 if (rootcontext) { 864 rc = -EINVAL; 865 printk(KERN_WARNING SEL_MOUNT_FAIL_MSG); 866 goto out_err; 867 } 868 rootcontext = match_strdup(&args[0]); 869 if (!rootcontext) { 870 rc = -ENOMEM; 871 goto out_err; 872 } 873 break; 874 875 case Opt_defcontext: 876 if (context || defcontext) { 877 rc = -EINVAL; 878 printk(KERN_WARNING SEL_MOUNT_FAIL_MSG); 879 goto out_err; 880 } 881 defcontext = match_strdup(&args[0]); 882 if (!defcontext) { 883 rc = -ENOMEM; 884 goto out_err; 885 } 886 break; 887 888 default: 889 rc = -EINVAL; 890 printk(KERN_WARNING "SELinux: unknown mount option\n"); 891 goto out_err; 892 893 } 894 } 895 896 rc = -ENOMEM; 897 opts->mnt_opts = kcalloc(NUM_SEL_MNT_OPTS, sizeof(char *), GFP_ATOMIC); 898 if (!opts->mnt_opts) 899 goto out_err; 900 901 opts->mnt_opts_flags = kcalloc(NUM_SEL_MNT_OPTS, sizeof(int), GFP_ATOMIC); 902 if (!opts->mnt_opts_flags) { 903 kfree(opts->mnt_opts); 904 goto out_err; 905 } 906 907 if (fscontext) { 908 opts->mnt_opts[num_mnt_opts] = fscontext; 909 opts->mnt_opts_flags[num_mnt_opts++] = FSCONTEXT_MNT; 910 } 911 if (context) { 912 opts->mnt_opts[num_mnt_opts] = context; 913 opts->mnt_opts_flags[num_mnt_opts++] = CONTEXT_MNT; 914 } 915 if (rootcontext) { 916 opts->mnt_opts[num_mnt_opts] = rootcontext; 917 opts->mnt_opts_flags[num_mnt_opts++] = ROOTCONTEXT_MNT; 918 } 919 if (defcontext) { 920 opts->mnt_opts[num_mnt_opts] = defcontext; 921 opts->mnt_opts_flags[num_mnt_opts++] = DEFCONTEXT_MNT; 922 } 923 924 opts->num_mnt_opts = num_mnt_opts; 925 return 0; 926 927 out_err: 928 kfree(context); 929 kfree(defcontext); 930 kfree(fscontext); 931 kfree(rootcontext); 932 return rc; 933 } 934 /* 935 * string mount options parsing and call set the sbsec 936 */ 937 static int superblock_doinit(struct super_block *sb, void *data) 938 { 939 int rc = 0; 940 char *options = data; 941 struct security_mnt_opts opts; 942 943 security_init_mnt_opts(&opts); 944 945 if (!data) 946 goto out; 947 948 BUG_ON(sb->s_type->fs_flags & FS_BINARY_MOUNTDATA); 949 950 rc = selinux_parse_opts_str(options, &opts); 951 if (rc) 952 goto out_err; 953 954 out: 955 rc = selinux_set_mnt_opts(sb, &opts); 956 957 out_err: 958 security_free_mnt_opts(&opts); 959 return rc; 960 } 961 962 static void selinux_write_opts(struct seq_file *m, 963 struct security_mnt_opts *opts) 964 { 965 int i; 966 char *prefix; 967 968 for (i = 0; i < opts->num_mnt_opts; i++) { 969 char *has_comma = strchr(opts->mnt_opts[i], ','); 970 971 switch (opts->mnt_opts_flags[i]) { 972 case CONTEXT_MNT: 973 prefix = CONTEXT_STR; 974 break; 975 case FSCONTEXT_MNT: 976 prefix = FSCONTEXT_STR; 977 break; 978 case ROOTCONTEXT_MNT: 979 prefix = ROOTCONTEXT_STR; 980 break; 981 case DEFCONTEXT_MNT: 982 prefix = DEFCONTEXT_STR; 983 break; 984 default: 985 BUG(); 986 }; 987 /* we need a comma before each option */ 988 seq_putc(m, ','); 989 seq_puts(m, prefix); 990 if (has_comma) 991 seq_putc(m, '\"'); 992 seq_puts(m, opts->mnt_opts[i]); 993 if (has_comma) 994 seq_putc(m, '\"'); 995 } 996 } 997 998 static int selinux_sb_show_options(struct seq_file *m, struct super_block *sb) 999 { 1000 struct security_mnt_opts opts; 1001 int rc; 1002 1003 rc = selinux_get_mnt_opts(sb, &opts); 1004 if (rc) { 1005 /* before policy load we may get EINVAL, don't show anything */ 1006 if (rc == -EINVAL) 1007 rc = 0; 1008 return rc; 1009 } 1010 1011 selinux_write_opts(m, &opts); 1012 1013 security_free_mnt_opts(&opts); 1014 1015 return rc; 1016 } 1017 1018 static inline u16 inode_mode_to_security_class(umode_t mode) 1019 { 1020 switch (mode & S_IFMT) { 1021 case S_IFSOCK: 1022 return SECCLASS_SOCK_FILE; 1023 case S_IFLNK: 1024 return SECCLASS_LNK_FILE; 1025 case S_IFREG: 1026 return SECCLASS_FILE; 1027 case S_IFBLK: 1028 return SECCLASS_BLK_FILE; 1029 case S_IFDIR: 1030 return SECCLASS_DIR; 1031 case S_IFCHR: 1032 return SECCLASS_CHR_FILE; 1033 case S_IFIFO: 1034 return SECCLASS_FIFO_FILE; 1035 1036 } 1037 1038 return SECCLASS_FILE; 1039 } 1040 1041 static inline int default_protocol_stream(int protocol) 1042 { 1043 return (protocol == IPPROTO_IP || protocol == IPPROTO_TCP); 1044 } 1045 1046 static inline int default_protocol_dgram(int protocol) 1047 { 1048 return (protocol == IPPROTO_IP || protocol == IPPROTO_UDP); 1049 } 1050 1051 static inline u16 socket_type_to_security_class(int family, int type, int protocol) 1052 { 1053 switch (family) { 1054 case PF_UNIX: 1055 switch (type) { 1056 case SOCK_STREAM: 1057 case SOCK_SEQPACKET: 1058 return SECCLASS_UNIX_STREAM_SOCKET; 1059 case SOCK_DGRAM: 1060 return SECCLASS_UNIX_DGRAM_SOCKET; 1061 } 1062 break; 1063 case PF_INET: 1064 case PF_INET6: 1065 switch (type) { 1066 case SOCK_STREAM: 1067 if (default_protocol_stream(protocol)) 1068 return SECCLASS_TCP_SOCKET; 1069 else 1070 return SECCLASS_RAWIP_SOCKET; 1071 case SOCK_DGRAM: 1072 if (default_protocol_dgram(protocol)) 1073 return SECCLASS_UDP_SOCKET; 1074 else 1075 return SECCLASS_RAWIP_SOCKET; 1076 case SOCK_DCCP: 1077 return SECCLASS_DCCP_SOCKET; 1078 default: 1079 return SECCLASS_RAWIP_SOCKET; 1080 } 1081 break; 1082 case PF_NETLINK: 1083 switch (protocol) { 1084 case NETLINK_ROUTE: 1085 return SECCLASS_NETLINK_ROUTE_SOCKET; 1086 case NETLINK_FIREWALL: 1087 return SECCLASS_NETLINK_FIREWALL_SOCKET; 1088 case NETLINK_INET_DIAG: 1089 return SECCLASS_NETLINK_TCPDIAG_SOCKET; 1090 case NETLINK_NFLOG: 1091 return SECCLASS_NETLINK_NFLOG_SOCKET; 1092 case NETLINK_XFRM: 1093 return SECCLASS_NETLINK_XFRM_SOCKET; 1094 case NETLINK_SELINUX: 1095 return SECCLASS_NETLINK_SELINUX_SOCKET; 1096 case NETLINK_AUDIT: 1097 return SECCLASS_NETLINK_AUDIT_SOCKET; 1098 case NETLINK_IP6_FW: 1099 return SECCLASS_NETLINK_IP6FW_SOCKET; 1100 case NETLINK_DNRTMSG: 1101 return SECCLASS_NETLINK_DNRT_SOCKET; 1102 case NETLINK_KOBJECT_UEVENT: 1103 return SECCLASS_NETLINK_KOBJECT_UEVENT_SOCKET; 1104 default: 1105 return SECCLASS_NETLINK_SOCKET; 1106 } 1107 case PF_PACKET: 1108 return SECCLASS_PACKET_SOCKET; 1109 case PF_KEY: 1110 return SECCLASS_KEY_SOCKET; 1111 case PF_APPLETALK: 1112 return SECCLASS_APPLETALK_SOCKET; 1113 } 1114 1115 return SECCLASS_SOCKET; 1116 } 1117 1118 #ifdef CONFIG_PROC_FS 1119 static int selinux_proc_get_sid(struct proc_dir_entry *de, 1120 u16 tclass, 1121 u32 *sid) 1122 { 1123 int buflen, rc; 1124 char *buffer, *path, *end; 1125 1126 buffer = (char *)__get_free_page(GFP_KERNEL); 1127 if (!buffer) 1128 return -ENOMEM; 1129 1130 buflen = PAGE_SIZE; 1131 end = buffer+buflen; 1132 *--end = '\0'; 1133 buflen--; 1134 path = end-1; 1135 *path = '/'; 1136 while (de && de != de->parent) { 1137 buflen -= de->namelen + 1; 1138 if (buflen < 0) 1139 break; 1140 end -= de->namelen; 1141 memcpy(end, de->name, de->namelen); 1142 *--end = '/'; 1143 path = end; 1144 de = de->parent; 1145 } 1146 rc = security_genfs_sid("proc", path, tclass, sid); 1147 free_page((unsigned long)buffer); 1148 return rc; 1149 } 1150 #else 1151 static int selinux_proc_get_sid(struct proc_dir_entry *de, 1152 u16 tclass, 1153 u32 *sid) 1154 { 1155 return -EINVAL; 1156 } 1157 #endif 1158 1159 /* The inode's security attributes must be initialized before first use. */ 1160 static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dentry) 1161 { 1162 struct superblock_security_struct *sbsec = NULL; 1163 struct inode_security_struct *isec = inode->i_security; 1164 u32 sid; 1165 struct dentry *dentry; 1166 #define INITCONTEXTLEN 255 1167 char *context = NULL; 1168 unsigned len = 0; 1169 int rc = 0; 1170 1171 if (isec->initialized) 1172 goto out; 1173 1174 mutex_lock(&isec->lock); 1175 if (isec->initialized) 1176 goto out_unlock; 1177 1178 sbsec = inode->i_sb->s_security; 1179 if (!sbsec->initialized) { 1180 /* Defer initialization until selinux_complete_init, 1181 after the initial policy is loaded and the security 1182 server is ready to handle calls. */ 1183 spin_lock(&sbsec->isec_lock); 1184 if (list_empty(&isec->list)) 1185 list_add(&isec->list, &sbsec->isec_head); 1186 spin_unlock(&sbsec->isec_lock); 1187 goto out_unlock; 1188 } 1189 1190 switch (sbsec->behavior) { 1191 case SECURITY_FS_USE_XATTR: 1192 if (!inode->i_op->getxattr) { 1193 isec->sid = sbsec->def_sid; 1194 break; 1195 } 1196 1197 /* Need a dentry, since the xattr API requires one. 1198 Life would be simpler if we could just pass the inode. */ 1199 if (opt_dentry) { 1200 /* Called from d_instantiate or d_splice_alias. */ 1201 dentry = dget(opt_dentry); 1202 } else { 1203 /* Called from selinux_complete_init, try to find a dentry. */ 1204 dentry = d_find_alias(inode); 1205 } 1206 if (!dentry) { 1207 printk(KERN_WARNING "SELinux: %s: no dentry for dev=%s " 1208 "ino=%ld\n", __func__, inode->i_sb->s_id, 1209 inode->i_ino); 1210 goto out_unlock; 1211 } 1212 1213 len = INITCONTEXTLEN; 1214 context = kmalloc(len, GFP_NOFS); 1215 if (!context) { 1216 rc = -ENOMEM; 1217 dput(dentry); 1218 goto out_unlock; 1219 } 1220 rc = inode->i_op->getxattr(dentry, XATTR_NAME_SELINUX, 1221 context, len); 1222 if (rc == -ERANGE) { 1223 /* Need a larger buffer. Query for the right size. */ 1224 rc = inode->i_op->getxattr(dentry, XATTR_NAME_SELINUX, 1225 NULL, 0); 1226 if (rc < 0) { 1227 dput(dentry); 1228 goto out_unlock; 1229 } 1230 kfree(context); 1231 len = rc; 1232 context = kmalloc(len, GFP_NOFS); 1233 if (!context) { 1234 rc = -ENOMEM; 1235 dput(dentry); 1236 goto out_unlock; 1237 } 1238 rc = inode->i_op->getxattr(dentry, 1239 XATTR_NAME_SELINUX, 1240 context, len); 1241 } 1242 dput(dentry); 1243 if (rc < 0) { 1244 if (rc != -ENODATA) { 1245 printk(KERN_WARNING "SELinux: %s: getxattr returned " 1246 "%d for dev=%s ino=%ld\n", __func__, 1247 -rc, inode->i_sb->s_id, inode->i_ino); 1248 kfree(context); 1249 goto out_unlock; 1250 } 1251 /* Map ENODATA to the default file SID */ 1252 sid = sbsec->def_sid; 1253 rc = 0; 1254 } else { 1255 rc = security_context_to_sid_default(context, rc, &sid, 1256 sbsec->def_sid, 1257 GFP_NOFS); 1258 if (rc) { 1259 printk(KERN_WARNING "SELinux: %s: context_to_sid(%s) " 1260 "returned %d for dev=%s ino=%ld\n", 1261 __func__, context, -rc, 1262 inode->i_sb->s_id, inode->i_ino); 1263 kfree(context); 1264 /* Leave with the unlabeled SID */ 1265 rc = 0; 1266 break; 1267 } 1268 } 1269 kfree(context); 1270 isec->sid = sid; 1271 break; 1272 case SECURITY_FS_USE_TASK: 1273 isec->sid = isec->task_sid; 1274 break; 1275 case SECURITY_FS_USE_TRANS: 1276 /* Default to the fs SID. */ 1277 isec->sid = sbsec->sid; 1278 1279 /* Try to obtain a transition SID. */ 1280 isec->sclass = inode_mode_to_security_class(inode->i_mode); 1281 rc = security_transition_sid(isec->task_sid, 1282 sbsec->sid, 1283 isec->sclass, 1284 &sid); 1285 if (rc) 1286 goto out_unlock; 1287 isec->sid = sid; 1288 break; 1289 case SECURITY_FS_USE_MNTPOINT: 1290 isec->sid = sbsec->mntpoint_sid; 1291 break; 1292 default: 1293 /* Default to the fs superblock SID. */ 1294 isec->sid = sbsec->sid; 1295 1296 if (sbsec->proc && !S_ISLNK(inode->i_mode)) { 1297 struct proc_inode *proci = PROC_I(inode); 1298 if (proci->pde) { 1299 isec->sclass = inode_mode_to_security_class(inode->i_mode); 1300 rc = selinux_proc_get_sid(proci->pde, 1301 isec->sclass, 1302 &sid); 1303 if (rc) 1304 goto out_unlock; 1305 isec->sid = sid; 1306 } 1307 } 1308 break; 1309 } 1310 1311 isec->initialized = 1; 1312 1313 out_unlock: 1314 mutex_unlock(&isec->lock); 1315 out: 1316 if (isec->sclass == SECCLASS_FILE) 1317 isec->sclass = inode_mode_to_security_class(inode->i_mode); 1318 return rc; 1319 } 1320 1321 /* Convert a Linux signal to an access vector. */ 1322 static inline u32 signal_to_av(int sig) 1323 { 1324 u32 perm = 0; 1325 1326 switch (sig) { 1327 case SIGCHLD: 1328 /* Commonly granted from child to parent. */ 1329 perm = PROCESS__SIGCHLD; 1330 break; 1331 case SIGKILL: 1332 /* Cannot be caught or ignored */ 1333 perm = PROCESS__SIGKILL; 1334 break; 1335 case SIGSTOP: 1336 /* Cannot be caught or ignored */ 1337 perm = PROCESS__SIGSTOP; 1338 break; 1339 default: 1340 /* All other signals. */ 1341 perm = PROCESS__SIGNAL; 1342 break; 1343 } 1344 1345 return perm; 1346 } 1347 1348 /* Check permission betweeen a pair of tasks, e.g. signal checks, 1349 fork check, ptrace check, etc. */ 1350 static int task_has_perm(struct task_struct *tsk1, 1351 struct task_struct *tsk2, 1352 u32 perms) 1353 { 1354 struct task_security_struct *tsec1, *tsec2; 1355 1356 tsec1 = tsk1->cred->security; 1357 tsec2 = tsk2->cred->security; 1358 return avc_has_perm(tsec1->sid, tsec2->sid, 1359 SECCLASS_PROCESS, perms, NULL); 1360 } 1361 1362 #if CAP_LAST_CAP > 63 1363 #error Fix SELinux to handle capabilities > 63. 1364 #endif 1365 1366 /* Check whether a task is allowed to use a capability. */ 1367 static int task_has_capability(struct task_struct *tsk, 1368 int cap, int audit) 1369 { 1370 struct task_security_struct *tsec; 1371 struct avc_audit_data ad; 1372 struct av_decision avd; 1373 u16 sclass; 1374 u32 av = CAP_TO_MASK(cap); 1375 int rc; 1376 1377 tsec = tsk->cred->security; 1378 1379 AVC_AUDIT_DATA_INIT(&ad, CAP); 1380 ad.tsk = tsk; 1381 ad.u.cap = cap; 1382 1383 switch (CAP_TO_INDEX(cap)) { 1384 case 0: 1385 sclass = SECCLASS_CAPABILITY; 1386 break; 1387 case 1: 1388 sclass = SECCLASS_CAPABILITY2; 1389 break; 1390 default: 1391 printk(KERN_ERR 1392 "SELinux: out of range capability %d\n", cap); 1393 BUG(); 1394 } 1395 1396 rc = avc_has_perm_noaudit(tsec->sid, tsec->sid, sclass, av, 0, &avd); 1397 if (audit == SECURITY_CAP_AUDIT) 1398 avc_audit(tsec->sid, tsec->sid, sclass, av, &avd, rc, &ad); 1399 return rc; 1400 } 1401 1402 /* Check whether a task is allowed to use a system operation. */ 1403 static int task_has_system(struct task_struct *tsk, 1404 u32 perms) 1405 { 1406 struct task_security_struct *tsec; 1407 1408 tsec = tsk->cred->security; 1409 1410 return avc_has_perm(tsec->sid, SECINITSID_KERNEL, 1411 SECCLASS_SYSTEM, perms, NULL); 1412 } 1413 1414 /* Check whether a task has a particular permission to an inode. 1415 The 'adp' parameter is optional and allows other audit 1416 data to be passed (e.g. the dentry). */ 1417 static int inode_has_perm(struct task_struct *tsk, 1418 struct inode *inode, 1419 u32 perms, 1420 struct avc_audit_data *adp) 1421 { 1422 struct task_security_struct *tsec; 1423 struct inode_security_struct *isec; 1424 struct avc_audit_data ad; 1425 1426 if (unlikely(IS_PRIVATE(inode))) 1427 return 0; 1428 1429 tsec = tsk->cred->security; 1430 isec = inode->i_security; 1431 1432 if (!adp) { 1433 adp = &ad; 1434 AVC_AUDIT_DATA_INIT(&ad, FS); 1435 ad.u.fs.inode = inode; 1436 } 1437 1438 return avc_has_perm(tsec->sid, isec->sid, isec->sclass, perms, adp); 1439 } 1440 1441 /* Same as inode_has_perm, but pass explicit audit data containing 1442 the dentry to help the auditing code to more easily generate the 1443 pathname if needed. */ 1444 static inline int dentry_has_perm(struct task_struct *tsk, 1445 struct vfsmount *mnt, 1446 struct dentry *dentry, 1447 u32 av) 1448 { 1449 struct inode *inode = dentry->d_inode; 1450 struct avc_audit_data ad; 1451 AVC_AUDIT_DATA_INIT(&ad, FS); 1452 ad.u.fs.path.mnt = mnt; 1453 ad.u.fs.path.dentry = dentry; 1454 return inode_has_perm(tsk, inode, av, &ad); 1455 } 1456 1457 /* Check whether a task can use an open file descriptor to 1458 access an inode in a given way. Check access to the 1459 descriptor itself, and then use dentry_has_perm to 1460 check a particular permission to the file. 1461 Access to the descriptor is implicitly granted if it 1462 has the same SID as the process. If av is zero, then 1463 access to the file is not checked, e.g. for cases 1464 where only the descriptor is affected like seek. */ 1465 static int file_has_perm(struct task_struct *tsk, 1466 struct file *file, 1467 u32 av) 1468 { 1469 struct task_security_struct *tsec = tsk->cred->security; 1470 struct file_security_struct *fsec = file->f_security; 1471 struct inode *inode = file->f_path.dentry->d_inode; 1472 struct avc_audit_data ad; 1473 int rc; 1474 1475 AVC_AUDIT_DATA_INIT(&ad, FS); 1476 ad.u.fs.path = file->f_path; 1477 1478 if (tsec->sid != fsec->sid) { 1479 rc = avc_has_perm(tsec->sid, fsec->sid, 1480 SECCLASS_FD, 1481 FD__USE, 1482 &ad); 1483 if (rc) 1484 return rc; 1485 } 1486 1487 /* av is zero if only checking access to the descriptor. */ 1488 if (av) 1489 return inode_has_perm(tsk, inode, av, &ad); 1490 1491 return 0; 1492 } 1493 1494 /* Check whether a task can create a file. */ 1495 static int may_create(struct inode *dir, 1496 struct dentry *dentry, 1497 u16 tclass) 1498 { 1499 struct task_security_struct *tsec; 1500 struct inode_security_struct *dsec; 1501 struct superblock_security_struct *sbsec; 1502 u32 newsid; 1503 struct avc_audit_data ad; 1504 int rc; 1505 1506 tsec = current->cred->security; 1507 dsec = dir->i_security; 1508 sbsec = dir->i_sb->s_security; 1509 1510 AVC_AUDIT_DATA_INIT(&ad, FS); 1511 ad.u.fs.path.dentry = dentry; 1512 1513 rc = avc_has_perm(tsec->sid, dsec->sid, SECCLASS_DIR, 1514 DIR__ADD_NAME | DIR__SEARCH, 1515 &ad); 1516 if (rc) 1517 return rc; 1518 1519 if (tsec->create_sid && sbsec->behavior != SECURITY_FS_USE_MNTPOINT) { 1520 newsid = tsec->create_sid; 1521 } else { 1522 rc = security_transition_sid(tsec->sid, dsec->sid, tclass, 1523 &newsid); 1524 if (rc) 1525 return rc; 1526 } 1527 1528 rc = avc_has_perm(tsec->sid, newsid, tclass, FILE__CREATE, &ad); 1529 if (rc) 1530 return rc; 1531 1532 return avc_has_perm(newsid, sbsec->sid, 1533 SECCLASS_FILESYSTEM, 1534 FILESYSTEM__ASSOCIATE, &ad); 1535 } 1536 1537 /* Check whether a task can create a key. */ 1538 static int may_create_key(u32 ksid, 1539 struct task_struct *ctx) 1540 { 1541 struct task_security_struct *tsec; 1542 1543 tsec = ctx->cred->security; 1544 1545 return avc_has_perm(tsec->sid, ksid, SECCLASS_KEY, KEY__CREATE, NULL); 1546 } 1547 1548 #define MAY_LINK 0 1549 #define MAY_UNLINK 1 1550 #define MAY_RMDIR 2 1551 1552 /* Check whether a task can link, unlink, or rmdir a file/directory. */ 1553 static int may_link(struct inode *dir, 1554 struct dentry *dentry, 1555 int kind) 1556 1557 { 1558 struct task_security_struct *tsec; 1559 struct inode_security_struct *dsec, *isec; 1560 struct avc_audit_data ad; 1561 u32 av; 1562 int rc; 1563 1564 tsec = current->cred->security; 1565 dsec = dir->i_security; 1566 isec = dentry->d_inode->i_security; 1567 1568 AVC_AUDIT_DATA_INIT(&ad, FS); 1569 ad.u.fs.path.dentry = dentry; 1570 1571 av = DIR__SEARCH; 1572 av |= (kind ? DIR__REMOVE_NAME : DIR__ADD_NAME); 1573 rc = avc_has_perm(tsec->sid, dsec->sid, SECCLASS_DIR, av, &ad); 1574 if (rc) 1575 return rc; 1576 1577 switch (kind) { 1578 case MAY_LINK: 1579 av = FILE__LINK; 1580 break; 1581 case MAY_UNLINK: 1582 av = FILE__UNLINK; 1583 break; 1584 case MAY_RMDIR: 1585 av = DIR__RMDIR; 1586 break; 1587 default: 1588 printk(KERN_WARNING "SELinux: %s: unrecognized kind %d\n", 1589 __func__, kind); 1590 return 0; 1591 } 1592 1593 rc = avc_has_perm(tsec->sid, isec->sid, isec->sclass, av, &ad); 1594 return rc; 1595 } 1596 1597 static inline int may_rename(struct inode *old_dir, 1598 struct dentry *old_dentry, 1599 struct inode *new_dir, 1600 struct dentry *new_dentry) 1601 { 1602 struct task_security_struct *tsec; 1603 struct inode_security_struct *old_dsec, *new_dsec, *old_isec, *new_isec; 1604 struct avc_audit_data ad; 1605 u32 av; 1606 int old_is_dir, new_is_dir; 1607 int rc; 1608 1609 tsec = current->cred->security; 1610 old_dsec = old_dir->i_security; 1611 old_isec = old_dentry->d_inode->i_security; 1612 old_is_dir = S_ISDIR(old_dentry->d_inode->i_mode); 1613 new_dsec = new_dir->i_security; 1614 1615 AVC_AUDIT_DATA_INIT(&ad, FS); 1616 1617 ad.u.fs.path.dentry = old_dentry; 1618 rc = avc_has_perm(tsec->sid, old_dsec->sid, SECCLASS_DIR, 1619 DIR__REMOVE_NAME | DIR__SEARCH, &ad); 1620 if (rc) 1621 return rc; 1622 rc = avc_has_perm(tsec->sid, old_isec->sid, 1623 old_isec->sclass, FILE__RENAME, &ad); 1624 if (rc) 1625 return rc; 1626 if (old_is_dir && new_dir != old_dir) { 1627 rc = avc_has_perm(tsec->sid, old_isec->sid, 1628 old_isec->sclass, DIR__REPARENT, &ad); 1629 if (rc) 1630 return rc; 1631 } 1632 1633 ad.u.fs.path.dentry = new_dentry; 1634 av = DIR__ADD_NAME | DIR__SEARCH; 1635 if (new_dentry->d_inode) 1636 av |= DIR__REMOVE_NAME; 1637 rc = avc_has_perm(tsec->sid, new_dsec->sid, SECCLASS_DIR, av, &ad); 1638 if (rc) 1639 return rc; 1640 if (new_dentry->d_inode) { 1641 new_isec = new_dentry->d_inode->i_security; 1642 new_is_dir = S_ISDIR(new_dentry->d_inode->i_mode); 1643 rc = avc_has_perm(tsec->sid, new_isec->sid, 1644 new_isec->sclass, 1645 (new_is_dir ? DIR__RMDIR : FILE__UNLINK), &ad); 1646 if (rc) 1647 return rc; 1648 } 1649 1650 return 0; 1651 } 1652 1653 /* Check whether a task can perform a filesystem operation. */ 1654 static int superblock_has_perm(struct task_struct *tsk, 1655 struct super_block *sb, 1656 u32 perms, 1657 struct avc_audit_data *ad) 1658 { 1659 struct task_security_struct *tsec; 1660 struct superblock_security_struct *sbsec; 1661 1662 tsec = tsk->cred->security; 1663 sbsec = sb->s_security; 1664 return avc_has_perm(tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM, 1665 perms, ad); 1666 } 1667 1668 /* Convert a Linux mode and permission mask to an access vector. */ 1669 static inline u32 file_mask_to_av(int mode, int mask) 1670 { 1671 u32 av = 0; 1672 1673 if ((mode & S_IFMT) != S_IFDIR) { 1674 if (mask & MAY_EXEC) 1675 av |= FILE__EXECUTE; 1676 if (mask & MAY_READ) 1677 av |= FILE__READ; 1678 1679 if (mask & MAY_APPEND) 1680 av |= FILE__APPEND; 1681 else if (mask & MAY_WRITE) 1682 av |= FILE__WRITE; 1683 1684 } else { 1685 if (mask & MAY_EXEC) 1686 av |= DIR__SEARCH; 1687 if (mask & MAY_WRITE) 1688 av |= DIR__WRITE; 1689 if (mask & MAY_READ) 1690 av |= DIR__READ; 1691 } 1692 1693 return av; 1694 } 1695 1696 /* Convert a Linux file to an access vector. */ 1697 static inline u32 file_to_av(struct file *file) 1698 { 1699 u32 av = 0; 1700 1701 if (file->f_mode & FMODE_READ) 1702 av |= FILE__READ; 1703 if (file->f_mode & FMODE_WRITE) { 1704 if (file->f_flags & O_APPEND) 1705 av |= FILE__APPEND; 1706 else 1707 av |= FILE__WRITE; 1708 } 1709 if (!av) { 1710 /* 1711 * Special file opened with flags 3 for ioctl-only use. 1712 */ 1713 av = FILE__IOCTL; 1714 } 1715 1716 return av; 1717 } 1718 1719 /* 1720 * Convert a file to an access vector and include the correct open 1721 * open permission. 1722 */ 1723 static inline u32 open_file_to_av(struct file *file) 1724 { 1725 u32 av = file_to_av(file); 1726 1727 if (selinux_policycap_openperm) { 1728 mode_t mode = file->f_path.dentry->d_inode->i_mode; 1729 /* 1730 * lnk files and socks do not really have an 'open' 1731 */ 1732 if (S_ISREG(mode)) 1733 av |= FILE__OPEN; 1734 else if (S_ISCHR(mode)) 1735 av |= CHR_FILE__OPEN; 1736 else if (S_ISBLK(mode)) 1737 av |= BLK_FILE__OPEN; 1738 else if (S_ISFIFO(mode)) 1739 av |= FIFO_FILE__OPEN; 1740 else if (S_ISDIR(mode)) 1741 av |= DIR__OPEN; 1742 else 1743 printk(KERN_ERR "SELinux: WARNING: inside %s with " 1744 "unknown mode:%o\n", __func__, mode); 1745 } 1746 return av; 1747 } 1748 1749 /* Hook functions begin here. */ 1750 1751 static int selinux_ptrace_may_access(struct task_struct *child, 1752 unsigned int mode) 1753 { 1754 int rc; 1755 1756 rc = secondary_ops->ptrace_may_access(child, mode); 1757 if (rc) 1758 return rc; 1759 1760 if (mode == PTRACE_MODE_READ) { 1761 struct task_security_struct *tsec = current->cred->security; 1762 struct task_security_struct *csec = child->cred->security; 1763 return avc_has_perm(tsec->sid, csec->sid, 1764 SECCLASS_FILE, FILE__READ, NULL); 1765 } 1766 1767 return task_has_perm(current, child, PROCESS__PTRACE); 1768 } 1769 1770 static int selinux_ptrace_traceme(struct task_struct *parent) 1771 { 1772 int rc; 1773 1774 rc = secondary_ops->ptrace_traceme(parent); 1775 if (rc) 1776 return rc; 1777 1778 return task_has_perm(parent, current, PROCESS__PTRACE); 1779 } 1780 1781 static int selinux_capget(struct task_struct *target, kernel_cap_t *effective, 1782 kernel_cap_t *inheritable, kernel_cap_t *permitted) 1783 { 1784 int error; 1785 1786 error = task_has_perm(current, target, PROCESS__GETCAP); 1787 if (error) 1788 return error; 1789 1790 return secondary_ops->capget(target, effective, inheritable, permitted); 1791 } 1792 1793 static int selinux_capset_check(const kernel_cap_t *effective, 1794 const kernel_cap_t *inheritable, 1795 const kernel_cap_t *permitted) 1796 { 1797 int error; 1798 1799 error = secondary_ops->capset_check(effective, inheritable, permitted); 1800 if (error) 1801 return error; 1802 1803 return task_has_perm(current, current, PROCESS__SETCAP); 1804 } 1805 1806 static void selinux_capset_set(const kernel_cap_t *effective, 1807 const kernel_cap_t *inheritable, 1808 const kernel_cap_t *permitted) 1809 { 1810 secondary_ops->capset_set(effective, inheritable, permitted); 1811 } 1812 1813 static int selinux_capable(struct task_struct *tsk, int cap, int audit) 1814 { 1815 int rc; 1816 1817 rc = secondary_ops->capable(tsk, cap, audit); 1818 if (rc) 1819 return rc; 1820 1821 return task_has_capability(tsk, cap, audit); 1822 } 1823 1824 static int selinux_sysctl_get_sid(ctl_table *table, u16 tclass, u32 *sid) 1825 { 1826 int buflen, rc; 1827 char *buffer, *path, *end; 1828 1829 rc = -ENOMEM; 1830 buffer = (char *)__get_free_page(GFP_KERNEL); 1831 if (!buffer) 1832 goto out; 1833 1834 buflen = PAGE_SIZE; 1835 end = buffer+buflen; 1836 *--end = '\0'; 1837 buflen--; 1838 path = end-1; 1839 *path = '/'; 1840 while (table) { 1841 const char *name = table->procname; 1842 size_t namelen = strlen(name); 1843 buflen -= namelen + 1; 1844 if (buflen < 0) 1845 goto out_free; 1846 end -= namelen; 1847 memcpy(end, name, namelen); 1848 *--end = '/'; 1849 path = end; 1850 table = table->parent; 1851 } 1852 buflen -= 4; 1853 if (buflen < 0) 1854 goto out_free; 1855 end -= 4; 1856 memcpy(end, "/sys", 4); 1857 path = end; 1858 rc = security_genfs_sid("proc", path, tclass, sid); 1859 out_free: 1860 free_page((unsigned long)buffer); 1861 out: 1862 return rc; 1863 } 1864 1865 static int selinux_sysctl(ctl_table *table, int op) 1866 { 1867 int error = 0; 1868 u32 av; 1869 struct task_security_struct *tsec; 1870 u32 tsid; 1871 int rc; 1872 1873 rc = secondary_ops->sysctl(table, op); 1874 if (rc) 1875 return rc; 1876 1877 tsec = current->cred->security; 1878 1879 rc = selinux_sysctl_get_sid(table, (op == 0001) ? 1880 SECCLASS_DIR : SECCLASS_FILE, &tsid); 1881 if (rc) { 1882 /* Default to the well-defined sysctl SID. */ 1883 tsid = SECINITSID_SYSCTL; 1884 } 1885 1886 /* The op values are "defined" in sysctl.c, thereby creating 1887 * a bad coupling between this module and sysctl.c */ 1888 if (op == 001) { 1889 error = avc_has_perm(tsec->sid, tsid, 1890 SECCLASS_DIR, DIR__SEARCH, NULL); 1891 } else { 1892 av = 0; 1893 if (op & 004) 1894 av |= FILE__READ; 1895 if (op & 002) 1896 av |= FILE__WRITE; 1897 if (av) 1898 error = avc_has_perm(tsec->sid, tsid, 1899 SECCLASS_FILE, av, NULL); 1900 } 1901 1902 return error; 1903 } 1904 1905 static int selinux_quotactl(int cmds, int type, int id, struct super_block *sb) 1906 { 1907 int rc = 0; 1908 1909 if (!sb) 1910 return 0; 1911 1912 switch (cmds) { 1913 case Q_SYNC: 1914 case Q_QUOTAON: 1915 case Q_QUOTAOFF: 1916 case Q_SETINFO: 1917 case Q_SETQUOTA: 1918 rc = superblock_has_perm(current, sb, FILESYSTEM__QUOTAMOD, 1919 NULL); 1920 break; 1921 case Q_GETFMT: 1922 case Q_GETINFO: 1923 case Q_GETQUOTA: 1924 rc = superblock_has_perm(current, sb, FILESYSTEM__QUOTAGET, 1925 NULL); 1926 break; 1927 default: 1928 rc = 0; /* let the kernel handle invalid cmds */ 1929 break; 1930 } 1931 return rc; 1932 } 1933 1934 static int selinux_quota_on(struct dentry *dentry) 1935 { 1936 return dentry_has_perm(current, NULL, dentry, FILE__QUOTAON); 1937 } 1938 1939 static int selinux_syslog(int type) 1940 { 1941 int rc; 1942 1943 rc = secondary_ops->syslog(type); 1944 if (rc) 1945 return rc; 1946 1947 switch (type) { 1948 case 3: /* Read last kernel messages */ 1949 case 10: /* Return size of the log buffer */ 1950 rc = task_has_system(current, SYSTEM__SYSLOG_READ); 1951 break; 1952 case 6: /* Disable logging to console */ 1953 case 7: /* Enable logging to console */ 1954 case 8: /* Set level of messages printed to console */ 1955 rc = task_has_system(current, SYSTEM__SYSLOG_CONSOLE); 1956 break; 1957 case 0: /* Close log */ 1958 case 1: /* Open log */ 1959 case 2: /* Read from log */ 1960 case 4: /* Read/clear last kernel messages */ 1961 case 5: /* Clear ring buffer */ 1962 default: 1963 rc = task_has_system(current, SYSTEM__SYSLOG_MOD); 1964 break; 1965 } 1966 return rc; 1967 } 1968 1969 /* 1970 * Check that a process has enough memory to allocate a new virtual 1971 * mapping. 0 means there is enough memory for the allocation to 1972 * succeed and -ENOMEM implies there is not. 1973 * 1974 * Note that secondary_ops->capable and task_has_perm_noaudit return 0 1975 * if the capability is granted, but __vm_enough_memory requires 1 if 1976 * the capability is granted. 1977 * 1978 * Do not audit the selinux permission check, as this is applied to all 1979 * processes that allocate mappings. 1980 */ 1981 static int selinux_vm_enough_memory(struct mm_struct *mm, long pages) 1982 { 1983 int rc, cap_sys_admin = 0; 1984 1985 rc = selinux_capable(current, CAP_SYS_ADMIN, SECURITY_CAP_NOAUDIT); 1986 if (rc == 0) 1987 cap_sys_admin = 1; 1988 1989 return __vm_enough_memory(mm, pages, cap_sys_admin); 1990 } 1991 1992 /* binprm security operations */ 1993 1994 static int selinux_bprm_alloc_security(struct linux_binprm *bprm) 1995 { 1996 struct bprm_security_struct *bsec; 1997 1998 bsec = kzalloc(sizeof(struct bprm_security_struct), GFP_KERNEL); 1999 if (!bsec) 2000 return -ENOMEM; 2001 2002 bsec->sid = SECINITSID_UNLABELED; 2003 bsec->set = 0; 2004 2005 bprm->security = bsec; 2006 return 0; 2007 } 2008 2009 static int selinux_bprm_set_security(struct linux_binprm *bprm) 2010 { 2011 struct task_security_struct *tsec; 2012 struct inode *inode = bprm->file->f_path.dentry->d_inode; 2013 struct inode_security_struct *isec; 2014 struct bprm_security_struct *bsec; 2015 u32 newsid; 2016 struct avc_audit_data ad; 2017 int rc; 2018 2019 rc = secondary_ops->bprm_set_security(bprm); 2020 if (rc) 2021 return rc; 2022 2023 bsec = bprm->security; 2024 2025 if (bsec->set) 2026 return 0; 2027 2028 tsec = current->cred->security; 2029 isec = inode->i_security; 2030 2031 /* Default to the current task SID. */ 2032 bsec->sid = tsec->sid; 2033 2034 /* Reset fs, key, and sock SIDs on execve. */ 2035 tsec->create_sid = 0; 2036 tsec->keycreate_sid = 0; 2037 tsec->sockcreate_sid = 0; 2038 2039 if (tsec->exec_sid) { 2040 newsid = tsec->exec_sid; 2041 /* Reset exec SID on execve. */ 2042 tsec->exec_sid = 0; 2043 } else { 2044 /* Check for a default transition on this program. */ 2045 rc = security_transition_sid(tsec->sid, isec->sid, 2046 SECCLASS_PROCESS, &newsid); 2047 if (rc) 2048 return rc; 2049 } 2050 2051 AVC_AUDIT_DATA_INIT(&ad, FS); 2052 ad.u.fs.path = bprm->file->f_path; 2053 2054 if (bprm->file->f_path.mnt->mnt_flags & MNT_NOSUID) 2055 newsid = tsec->sid; 2056 2057 if (tsec->sid == newsid) { 2058 rc = avc_has_perm(tsec->sid, isec->sid, 2059 SECCLASS_FILE, FILE__EXECUTE_NO_TRANS, &ad); 2060 if (rc) 2061 return rc; 2062 } else { 2063 /* Check permissions for the transition. */ 2064 rc = avc_has_perm(tsec->sid, newsid, 2065 SECCLASS_PROCESS, PROCESS__TRANSITION, &ad); 2066 if (rc) 2067 return rc; 2068 2069 rc = avc_has_perm(newsid, isec->sid, 2070 SECCLASS_FILE, FILE__ENTRYPOINT, &ad); 2071 if (rc) 2072 return rc; 2073 2074 /* Clear any possibly unsafe personality bits on exec: */ 2075 current->personality &= ~PER_CLEAR_ON_SETID; 2076 2077 /* Set the security field to the new SID. */ 2078 bsec->sid = newsid; 2079 } 2080 2081 bsec->set = 1; 2082 return 0; 2083 } 2084 2085 static int selinux_bprm_check_security(struct linux_binprm *bprm) 2086 { 2087 return secondary_ops->bprm_check_security(bprm); 2088 } 2089 2090 2091 static int selinux_bprm_secureexec(struct linux_binprm *bprm) 2092 { 2093 struct task_security_struct *tsec = current->cred->security; 2094 int atsecure = 0; 2095 2096 if (tsec->osid != tsec->sid) { 2097 /* Enable secure mode for SIDs transitions unless 2098 the noatsecure permission is granted between 2099 the two SIDs, i.e. ahp returns 0. */ 2100 atsecure = avc_has_perm(tsec->osid, tsec->sid, 2101 SECCLASS_PROCESS, 2102 PROCESS__NOATSECURE, NULL); 2103 } 2104 2105 return (atsecure || secondary_ops->bprm_secureexec(bprm)); 2106 } 2107 2108 static void selinux_bprm_free_security(struct linux_binprm *bprm) 2109 { 2110 kfree(bprm->security); 2111 bprm->security = NULL; 2112 } 2113 2114 extern struct vfsmount *selinuxfs_mount; 2115 extern struct dentry *selinux_null; 2116 2117 /* Derived from fs/exec.c:flush_old_files. */ 2118 static inline void flush_unauthorized_files(struct files_struct *files) 2119 { 2120 struct avc_audit_data ad; 2121 struct file *file, *devnull = NULL; 2122 struct tty_struct *tty; 2123 struct fdtable *fdt; 2124 long j = -1; 2125 int drop_tty = 0; 2126 2127 tty = get_current_tty(); 2128 if (tty) { 2129 file_list_lock(); 2130 if (!list_empty(&tty->tty_files)) { 2131 struct inode *inode; 2132 2133 /* Revalidate access to controlling tty. 2134 Use inode_has_perm on the tty inode directly rather 2135 than using file_has_perm, as this particular open 2136 file may belong to another process and we are only 2137 interested in the inode-based check here. */ 2138 file = list_first_entry(&tty->tty_files, struct file, f_u.fu_list); 2139 inode = file->f_path.dentry->d_inode; 2140 if (inode_has_perm(current, inode, 2141 FILE__READ | FILE__WRITE, NULL)) { 2142 drop_tty = 1; 2143 } 2144 } 2145 file_list_unlock(); 2146 tty_kref_put(tty); 2147 } 2148 /* Reset controlling tty. */ 2149 if (drop_tty) 2150 no_tty(); 2151 2152 /* Revalidate access to inherited open files. */ 2153 2154 AVC_AUDIT_DATA_INIT(&ad, FS); 2155 2156 spin_lock(&files->file_lock); 2157 for (;;) { 2158 unsigned long set, i; 2159 int fd; 2160 2161 j++; 2162 i = j * __NFDBITS; 2163 fdt = files_fdtable(files); 2164 if (i >= fdt->max_fds) 2165 break; 2166 set = fdt->open_fds->fds_bits[j]; 2167 if (!set) 2168 continue; 2169 spin_unlock(&files->file_lock); 2170 for ( ; set ; i++, set >>= 1) { 2171 if (set & 1) { 2172 file = fget(i); 2173 if (!file) 2174 continue; 2175 if (file_has_perm(current, 2176 file, 2177 file_to_av(file))) { 2178 sys_close(i); 2179 fd = get_unused_fd(); 2180 if (fd != i) { 2181 if (fd >= 0) 2182 put_unused_fd(fd); 2183 fput(file); 2184 continue; 2185 } 2186 if (devnull) { 2187 get_file(devnull); 2188 } else { 2189 devnull = dentry_open(dget(selinux_null), mntget(selinuxfs_mount), O_RDWR); 2190 if (IS_ERR(devnull)) { 2191 devnull = NULL; 2192 put_unused_fd(fd); 2193 fput(file); 2194 continue; 2195 } 2196 } 2197 fd_install(fd, devnull); 2198 } 2199 fput(file); 2200 } 2201 } 2202 spin_lock(&files->file_lock); 2203 2204 } 2205 spin_unlock(&files->file_lock); 2206 } 2207 2208 static void selinux_bprm_apply_creds(struct linux_binprm *bprm, int unsafe) 2209 { 2210 struct task_security_struct *tsec; 2211 struct bprm_security_struct *bsec; 2212 u32 sid; 2213 int rc; 2214 2215 secondary_ops->bprm_apply_creds(bprm, unsafe); 2216 2217 tsec = current->cred->security; 2218 2219 bsec = bprm->security; 2220 sid = bsec->sid; 2221 2222 tsec->osid = tsec->sid; 2223 bsec->unsafe = 0; 2224 if (tsec->sid != sid) { 2225 /* Check for shared state. If not ok, leave SID 2226 unchanged and kill. */ 2227 if (unsafe & LSM_UNSAFE_SHARE) { 2228 rc = avc_has_perm(tsec->sid, sid, SECCLASS_PROCESS, 2229 PROCESS__SHARE, NULL); 2230 if (rc) { 2231 bsec->unsafe = 1; 2232 return; 2233 } 2234 } 2235 2236 /* Check for ptracing, and update the task SID if ok. 2237 Otherwise, leave SID unchanged and kill. */ 2238 if (unsafe & (LSM_UNSAFE_PTRACE | LSM_UNSAFE_PTRACE_CAP)) { 2239 struct task_struct *tracer; 2240 struct task_security_struct *sec; 2241 u32 ptsid = 0; 2242 2243 rcu_read_lock(); 2244 tracer = tracehook_tracer_task(current); 2245 if (likely(tracer != NULL)) { 2246 sec = tracer->cred->security; 2247 ptsid = sec->sid; 2248 } 2249 rcu_read_unlock(); 2250 2251 if (ptsid != 0) { 2252 rc = avc_has_perm(ptsid, sid, SECCLASS_PROCESS, 2253 PROCESS__PTRACE, NULL); 2254 if (rc) { 2255 bsec->unsafe = 1; 2256 return; 2257 } 2258 } 2259 } 2260 tsec->sid = sid; 2261 } 2262 } 2263 2264 /* 2265 * called after apply_creds without the task lock held 2266 */ 2267 static void selinux_bprm_post_apply_creds(struct linux_binprm *bprm) 2268 { 2269 struct task_security_struct *tsec; 2270 struct rlimit *rlim, *initrlim; 2271 struct itimerval itimer; 2272 struct bprm_security_struct *bsec; 2273 struct sighand_struct *psig; 2274 int rc, i; 2275 unsigned long flags; 2276 2277 tsec = current->cred->security; 2278 bsec = bprm->security; 2279 2280 if (bsec->unsafe) { 2281 force_sig_specific(SIGKILL, current); 2282 return; 2283 } 2284 if (tsec->osid == tsec->sid) 2285 return; 2286 2287 /* Close files for which the new task SID is not authorized. */ 2288 flush_unauthorized_files(current->files); 2289 2290 /* Check whether the new SID can inherit signal state 2291 from the old SID. If not, clear itimers to avoid 2292 subsequent signal generation and flush and unblock 2293 signals. This must occur _after_ the task SID has 2294 been updated so that any kill done after the flush 2295 will be checked against the new SID. */ 2296 rc = avc_has_perm(tsec->osid, tsec->sid, SECCLASS_PROCESS, 2297 PROCESS__SIGINH, NULL); 2298 if (rc) { 2299 memset(&itimer, 0, sizeof itimer); 2300 for (i = 0; i < 3; i++) 2301 do_setitimer(i, &itimer, NULL); 2302 flush_signals(current); 2303 spin_lock_irq(¤t->sighand->siglock); 2304 flush_signal_handlers(current, 1); 2305 sigemptyset(¤t->blocked); 2306 recalc_sigpending(); 2307 spin_unlock_irq(¤t->sighand->siglock); 2308 } 2309 2310 /* Always clear parent death signal on SID transitions. */ 2311 current->pdeath_signal = 0; 2312 2313 /* Check whether the new SID can inherit resource limits 2314 from the old SID. If not, reset all soft limits to 2315 the lower of the current task's hard limit and the init 2316 task's soft limit. Note that the setting of hard limits 2317 (even to lower them) can be controlled by the setrlimit 2318 check. The inclusion of the init task's soft limit into 2319 the computation is to avoid resetting soft limits higher 2320 than the default soft limit for cases where the default 2321 is lower than the hard limit, e.g. RLIMIT_CORE or 2322 RLIMIT_STACK.*/ 2323 rc = avc_has_perm(tsec->osid, tsec->sid, SECCLASS_PROCESS, 2324 PROCESS__RLIMITINH, NULL); 2325 if (rc) { 2326 for (i = 0; i < RLIM_NLIMITS; i++) { 2327 rlim = current->signal->rlim + i; 2328 initrlim = init_task.signal->rlim+i; 2329 rlim->rlim_cur = min(rlim->rlim_max, initrlim->rlim_cur); 2330 } 2331 update_rlimit_cpu(rlim->rlim_cur); 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 read_lock_irq(&tasklist_lock); 2337 psig = current->parent->sighand; 2338 spin_lock_irqsave(&psig->siglock, flags); 2339 wake_up_interruptible(¤t->parent->signal->wait_chldexit); 2340 spin_unlock_irqrestore(&psig->siglock, flags); 2341 read_unlock_irq(&tasklist_lock); 2342 } 2343 2344 /* superblock security operations */ 2345 2346 static int selinux_sb_alloc_security(struct super_block *sb) 2347 { 2348 return superblock_alloc_security(sb); 2349 } 2350 2351 static void selinux_sb_free_security(struct super_block *sb) 2352 { 2353 superblock_free_security(sb); 2354 } 2355 2356 static inline int match_prefix(char *prefix, int plen, char *option, int olen) 2357 { 2358 if (plen > olen) 2359 return 0; 2360 2361 return !memcmp(prefix, option, plen); 2362 } 2363 2364 static inline int selinux_option(char *option, int len) 2365 { 2366 return (match_prefix(CONTEXT_STR, sizeof(CONTEXT_STR)-1, option, len) || 2367 match_prefix(FSCONTEXT_STR, sizeof(FSCONTEXT_STR)-1, option, len) || 2368 match_prefix(DEFCONTEXT_STR, sizeof(DEFCONTEXT_STR)-1, option, len) || 2369 match_prefix(ROOTCONTEXT_STR, sizeof(ROOTCONTEXT_STR)-1, option, len)); 2370 } 2371 2372 static inline void take_option(char **to, char *from, int *first, int len) 2373 { 2374 if (!*first) { 2375 **to = ','; 2376 *to += 1; 2377 } else 2378 *first = 0; 2379 memcpy(*to, from, len); 2380 *to += len; 2381 } 2382 2383 static inline void take_selinux_option(char **to, char *from, int *first, 2384 int len) 2385 { 2386 int current_size = 0; 2387 2388 if (!*first) { 2389 **to = '|'; 2390 *to += 1; 2391 } else 2392 *first = 0; 2393 2394 while (current_size < len) { 2395 if (*from != '"') { 2396 **to = *from; 2397 *to += 1; 2398 } 2399 from += 1; 2400 current_size += 1; 2401 } 2402 } 2403 2404 static int selinux_sb_copy_data(char *orig, char *copy) 2405 { 2406 int fnosec, fsec, rc = 0; 2407 char *in_save, *in_curr, *in_end; 2408 char *sec_curr, *nosec_save, *nosec; 2409 int open_quote = 0; 2410 2411 in_curr = orig; 2412 sec_curr = copy; 2413 2414 nosec = (char *)get_zeroed_page(GFP_KERNEL); 2415 if (!nosec) { 2416 rc = -ENOMEM; 2417 goto out; 2418 } 2419 2420 nosec_save = nosec; 2421 fnosec = fsec = 1; 2422 in_save = in_end = orig; 2423 2424 do { 2425 if (*in_end == '"') 2426 open_quote = !open_quote; 2427 if ((*in_end == ',' && open_quote == 0) || 2428 *in_end == '\0') { 2429 int len = in_end - in_curr; 2430 2431 if (selinux_option(in_curr, len)) 2432 take_selinux_option(&sec_curr, in_curr, &fsec, len); 2433 else 2434 take_option(&nosec, in_curr, &fnosec, len); 2435 2436 in_curr = in_end + 1; 2437 } 2438 } while (*in_end++); 2439 2440 strcpy(in_save, nosec_save); 2441 free_page((unsigned long)nosec_save); 2442 out: 2443 return rc; 2444 } 2445 2446 static int selinux_sb_kern_mount(struct super_block *sb, void *data) 2447 { 2448 struct avc_audit_data ad; 2449 int rc; 2450 2451 rc = superblock_doinit(sb, data); 2452 if (rc) 2453 return rc; 2454 2455 AVC_AUDIT_DATA_INIT(&ad, FS); 2456 ad.u.fs.path.dentry = sb->s_root; 2457 return superblock_has_perm(current, sb, FILESYSTEM__MOUNT, &ad); 2458 } 2459 2460 static int selinux_sb_statfs(struct dentry *dentry) 2461 { 2462 struct avc_audit_data ad; 2463 2464 AVC_AUDIT_DATA_INIT(&ad, FS); 2465 ad.u.fs.path.dentry = dentry->d_sb->s_root; 2466 return superblock_has_perm(current, dentry->d_sb, FILESYSTEM__GETATTR, &ad); 2467 } 2468 2469 static int selinux_mount(char *dev_name, 2470 struct path *path, 2471 char *type, 2472 unsigned long flags, 2473 void *data) 2474 { 2475 int rc; 2476 2477 rc = secondary_ops->sb_mount(dev_name, path, type, flags, data); 2478 if (rc) 2479 return rc; 2480 2481 if (flags & MS_REMOUNT) 2482 return superblock_has_perm(current, path->mnt->mnt_sb, 2483 FILESYSTEM__REMOUNT, NULL); 2484 else 2485 return dentry_has_perm(current, path->mnt, path->dentry, 2486 FILE__MOUNTON); 2487 } 2488 2489 static int selinux_umount(struct vfsmount *mnt, int flags) 2490 { 2491 int rc; 2492 2493 rc = secondary_ops->sb_umount(mnt, flags); 2494 if (rc) 2495 return rc; 2496 2497 return superblock_has_perm(current, mnt->mnt_sb, 2498 FILESYSTEM__UNMOUNT, NULL); 2499 } 2500 2501 /* inode security operations */ 2502 2503 static int selinux_inode_alloc_security(struct inode *inode) 2504 { 2505 return inode_alloc_security(inode); 2506 } 2507 2508 static void selinux_inode_free_security(struct inode *inode) 2509 { 2510 inode_free_security(inode); 2511 } 2512 2513 static int selinux_inode_init_security(struct inode *inode, struct inode *dir, 2514 char **name, void **value, 2515 size_t *len) 2516 { 2517 struct task_security_struct *tsec; 2518 struct inode_security_struct *dsec; 2519 struct superblock_security_struct *sbsec; 2520 u32 newsid, clen; 2521 int rc; 2522 char *namep = NULL, *context; 2523 2524 tsec = current->cred->security; 2525 dsec = dir->i_security; 2526 sbsec = dir->i_sb->s_security; 2527 2528 if (tsec->create_sid && sbsec->behavior != SECURITY_FS_USE_MNTPOINT) { 2529 newsid = tsec->create_sid; 2530 } else { 2531 rc = security_transition_sid(tsec->sid, dsec->sid, 2532 inode_mode_to_security_class(inode->i_mode), 2533 &newsid); 2534 if (rc) { 2535 printk(KERN_WARNING "%s: " 2536 "security_transition_sid failed, rc=%d (dev=%s " 2537 "ino=%ld)\n", 2538 __func__, 2539 -rc, inode->i_sb->s_id, inode->i_ino); 2540 return rc; 2541 } 2542 } 2543 2544 /* Possibly defer initialization to selinux_complete_init. */ 2545 if (sbsec->initialized) { 2546 struct inode_security_struct *isec = inode->i_security; 2547 isec->sclass = inode_mode_to_security_class(inode->i_mode); 2548 isec->sid = newsid; 2549 isec->initialized = 1; 2550 } 2551 2552 if (!ss_initialized || sbsec->behavior == SECURITY_FS_USE_MNTPOINT) 2553 return -EOPNOTSUPP; 2554 2555 if (name) { 2556 namep = kstrdup(XATTR_SELINUX_SUFFIX, GFP_NOFS); 2557 if (!namep) 2558 return -ENOMEM; 2559 *name = namep; 2560 } 2561 2562 if (value && len) { 2563 rc = security_sid_to_context_force(newsid, &context, &clen); 2564 if (rc) { 2565 kfree(namep); 2566 return rc; 2567 } 2568 *value = context; 2569 *len = clen; 2570 } 2571 2572 return 0; 2573 } 2574 2575 static int selinux_inode_create(struct inode *dir, struct dentry *dentry, int mask) 2576 { 2577 return may_create(dir, dentry, SECCLASS_FILE); 2578 } 2579 2580 static int selinux_inode_link(struct dentry *old_dentry, struct inode *dir, struct dentry *new_dentry) 2581 { 2582 int rc; 2583 2584 rc = secondary_ops->inode_link(old_dentry, dir, new_dentry); 2585 if (rc) 2586 return rc; 2587 return may_link(dir, old_dentry, MAY_LINK); 2588 } 2589 2590 static int selinux_inode_unlink(struct inode *dir, struct dentry *dentry) 2591 { 2592 int rc; 2593 2594 rc = secondary_ops->inode_unlink(dir, dentry); 2595 if (rc) 2596 return rc; 2597 return may_link(dir, dentry, MAY_UNLINK); 2598 } 2599 2600 static int selinux_inode_symlink(struct inode *dir, struct dentry *dentry, const char *name) 2601 { 2602 return may_create(dir, dentry, SECCLASS_LNK_FILE); 2603 } 2604 2605 static int selinux_inode_mkdir(struct inode *dir, struct dentry *dentry, int mask) 2606 { 2607 return may_create(dir, dentry, SECCLASS_DIR); 2608 } 2609 2610 static int selinux_inode_rmdir(struct inode *dir, struct dentry *dentry) 2611 { 2612 return may_link(dir, dentry, MAY_RMDIR); 2613 } 2614 2615 static int selinux_inode_mknod(struct inode *dir, struct dentry *dentry, int mode, dev_t dev) 2616 { 2617 int rc; 2618 2619 rc = secondary_ops->inode_mknod(dir, dentry, mode, dev); 2620 if (rc) 2621 return rc; 2622 2623 return may_create(dir, dentry, inode_mode_to_security_class(mode)); 2624 } 2625 2626 static int selinux_inode_rename(struct inode *old_inode, struct dentry *old_dentry, 2627 struct inode *new_inode, struct dentry *new_dentry) 2628 { 2629 return may_rename(old_inode, old_dentry, new_inode, new_dentry); 2630 } 2631 2632 static int selinux_inode_readlink(struct dentry *dentry) 2633 { 2634 return dentry_has_perm(current, NULL, dentry, FILE__READ); 2635 } 2636 2637 static int selinux_inode_follow_link(struct dentry *dentry, struct nameidata *nameidata) 2638 { 2639 int rc; 2640 2641 rc = secondary_ops->inode_follow_link(dentry, nameidata); 2642 if (rc) 2643 return rc; 2644 return dentry_has_perm(current, NULL, dentry, FILE__READ); 2645 } 2646 2647 static int selinux_inode_permission(struct inode *inode, int mask) 2648 { 2649 int rc; 2650 2651 rc = secondary_ops->inode_permission(inode, mask); 2652 if (rc) 2653 return rc; 2654 2655 if (!mask) { 2656 /* No permission to check. Existence test. */ 2657 return 0; 2658 } 2659 2660 return inode_has_perm(current, inode, 2661 file_mask_to_av(inode->i_mode, mask), NULL); 2662 } 2663 2664 static int selinux_inode_setattr(struct dentry *dentry, struct iattr *iattr) 2665 { 2666 int rc; 2667 2668 rc = secondary_ops->inode_setattr(dentry, iattr); 2669 if (rc) 2670 return rc; 2671 2672 if (iattr->ia_valid & ATTR_FORCE) 2673 return 0; 2674 2675 if (iattr->ia_valid & (ATTR_MODE | ATTR_UID | ATTR_GID | 2676 ATTR_ATIME_SET | ATTR_MTIME_SET)) 2677 return dentry_has_perm(current, NULL, dentry, FILE__SETATTR); 2678 2679 return dentry_has_perm(current, NULL, dentry, FILE__WRITE); 2680 } 2681 2682 static int selinux_inode_getattr(struct vfsmount *mnt, struct dentry *dentry) 2683 { 2684 return dentry_has_perm(current, mnt, dentry, FILE__GETATTR); 2685 } 2686 2687 static int selinux_inode_setotherxattr(struct dentry *dentry, const char *name) 2688 { 2689 if (!strncmp(name, XATTR_SECURITY_PREFIX, 2690 sizeof XATTR_SECURITY_PREFIX - 1)) { 2691 if (!strcmp(name, XATTR_NAME_CAPS)) { 2692 if (!capable(CAP_SETFCAP)) 2693 return -EPERM; 2694 } else if (!capable(CAP_SYS_ADMIN)) { 2695 /* A different attribute in the security namespace. 2696 Restrict to administrator. */ 2697 return -EPERM; 2698 } 2699 } 2700 2701 /* Not an attribute we recognize, so just check the 2702 ordinary setattr permission. */ 2703 return dentry_has_perm(current, NULL, dentry, FILE__SETATTR); 2704 } 2705 2706 static int selinux_inode_setxattr(struct dentry *dentry, const char *name, 2707 const void *value, size_t size, int flags) 2708 { 2709 struct task_security_struct *tsec = current->cred->security; 2710 struct inode *inode = dentry->d_inode; 2711 struct inode_security_struct *isec = inode->i_security; 2712 struct superblock_security_struct *sbsec; 2713 struct avc_audit_data ad; 2714 u32 newsid; 2715 int rc = 0; 2716 2717 if (strcmp(name, XATTR_NAME_SELINUX)) 2718 return selinux_inode_setotherxattr(dentry, name); 2719 2720 sbsec = inode->i_sb->s_security; 2721 if (sbsec->behavior == SECURITY_FS_USE_MNTPOINT) 2722 return -EOPNOTSUPP; 2723 2724 if (!is_owner_or_cap(inode)) 2725 return -EPERM; 2726 2727 AVC_AUDIT_DATA_INIT(&ad, FS); 2728 ad.u.fs.path.dentry = dentry; 2729 2730 rc = avc_has_perm(tsec->sid, isec->sid, isec->sclass, 2731 FILE__RELABELFROM, &ad); 2732 if (rc) 2733 return rc; 2734 2735 rc = security_context_to_sid(value, size, &newsid); 2736 if (rc == -EINVAL) { 2737 if (!capable(CAP_MAC_ADMIN)) 2738 return rc; 2739 rc = security_context_to_sid_force(value, size, &newsid); 2740 } 2741 if (rc) 2742 return rc; 2743 2744 rc = avc_has_perm(tsec->sid, newsid, isec->sclass, 2745 FILE__RELABELTO, &ad); 2746 if (rc) 2747 return rc; 2748 2749 rc = security_validate_transition(isec->sid, newsid, tsec->sid, 2750 isec->sclass); 2751 if (rc) 2752 return rc; 2753 2754 return avc_has_perm(newsid, 2755 sbsec->sid, 2756 SECCLASS_FILESYSTEM, 2757 FILESYSTEM__ASSOCIATE, 2758 &ad); 2759 } 2760 2761 static void selinux_inode_post_setxattr(struct dentry *dentry, const char *name, 2762 const void *value, size_t size, 2763 int flags) 2764 { 2765 struct inode *inode = dentry->d_inode; 2766 struct inode_security_struct *isec = inode->i_security; 2767 u32 newsid; 2768 int rc; 2769 2770 if (strcmp(name, XATTR_NAME_SELINUX)) { 2771 /* Not an attribute we recognize, so nothing to do. */ 2772 return; 2773 } 2774 2775 rc = security_context_to_sid_force(value, size, &newsid); 2776 if (rc) { 2777 printk(KERN_ERR "SELinux: unable to map context to SID" 2778 "for (%s, %lu), rc=%d\n", 2779 inode->i_sb->s_id, inode->i_ino, -rc); 2780 return; 2781 } 2782 2783 isec->sid = newsid; 2784 return; 2785 } 2786 2787 static int selinux_inode_getxattr(struct dentry *dentry, const char *name) 2788 { 2789 return dentry_has_perm(current, NULL, dentry, FILE__GETATTR); 2790 } 2791 2792 static int selinux_inode_listxattr(struct dentry *dentry) 2793 { 2794 return dentry_has_perm(current, NULL, dentry, FILE__GETATTR); 2795 } 2796 2797 static int selinux_inode_removexattr(struct dentry *dentry, const char *name) 2798 { 2799 if (strcmp(name, XATTR_NAME_SELINUX)) 2800 return selinux_inode_setotherxattr(dentry, name); 2801 2802 /* No one is allowed to remove a SELinux security label. 2803 You can change the label, but all data must be labeled. */ 2804 return -EACCES; 2805 } 2806 2807 /* 2808 * Copy the inode security context value to the user. 2809 * 2810 * Permission check is handled by selinux_inode_getxattr hook. 2811 */ 2812 static int selinux_inode_getsecurity(const struct inode *inode, const char *name, void **buffer, bool alloc) 2813 { 2814 u32 size; 2815 int error; 2816 char *context = NULL; 2817 struct inode_security_struct *isec = inode->i_security; 2818 2819 if (strcmp(name, XATTR_SELINUX_SUFFIX)) 2820 return -EOPNOTSUPP; 2821 2822 /* 2823 * If the caller has CAP_MAC_ADMIN, then get the raw context 2824 * value even if it is not defined by current policy; otherwise, 2825 * use the in-core value under current policy. 2826 * Use the non-auditing forms of the permission checks since 2827 * getxattr may be called by unprivileged processes commonly 2828 * and lack of permission just means that we fall back to the 2829 * in-core context value, not a denial. 2830 */ 2831 error = selinux_capable(current, CAP_MAC_ADMIN, SECURITY_CAP_NOAUDIT); 2832 if (!error) 2833 error = security_sid_to_context_force(isec->sid, &context, 2834 &size); 2835 else 2836 error = security_sid_to_context(isec->sid, &context, &size); 2837 if (error) 2838 return error; 2839 error = size; 2840 if (alloc) { 2841 *buffer = context; 2842 goto out_nofree; 2843 } 2844 kfree(context); 2845 out_nofree: 2846 return error; 2847 } 2848 2849 static int selinux_inode_setsecurity(struct inode *inode, const char *name, 2850 const void *value, size_t size, int flags) 2851 { 2852 struct inode_security_struct *isec = inode->i_security; 2853 u32 newsid; 2854 int rc; 2855 2856 if (strcmp(name, XATTR_SELINUX_SUFFIX)) 2857 return -EOPNOTSUPP; 2858 2859 if (!value || !size) 2860 return -EACCES; 2861 2862 rc = security_context_to_sid((void *)value, size, &newsid); 2863 if (rc) 2864 return rc; 2865 2866 isec->sid = newsid; 2867 return 0; 2868 } 2869 2870 static int selinux_inode_listsecurity(struct inode *inode, char *buffer, size_t buffer_size) 2871 { 2872 const int len = sizeof(XATTR_NAME_SELINUX); 2873 if (buffer && len <= buffer_size) 2874 memcpy(buffer, XATTR_NAME_SELINUX, len); 2875 return len; 2876 } 2877 2878 static int selinux_inode_need_killpriv(struct dentry *dentry) 2879 { 2880 return secondary_ops->inode_need_killpriv(dentry); 2881 } 2882 2883 static int selinux_inode_killpriv(struct dentry *dentry) 2884 { 2885 return secondary_ops->inode_killpriv(dentry); 2886 } 2887 2888 static void selinux_inode_getsecid(const struct inode *inode, u32 *secid) 2889 { 2890 struct inode_security_struct *isec = inode->i_security; 2891 *secid = isec->sid; 2892 } 2893 2894 /* file security operations */ 2895 2896 static int selinux_revalidate_file_permission(struct file *file, int mask) 2897 { 2898 int rc; 2899 struct inode *inode = file->f_path.dentry->d_inode; 2900 2901 if (!mask) { 2902 /* No permission to check. Existence test. */ 2903 return 0; 2904 } 2905 2906 /* file_mask_to_av won't add FILE__WRITE if MAY_APPEND is set */ 2907 if ((file->f_flags & O_APPEND) && (mask & MAY_WRITE)) 2908 mask |= MAY_APPEND; 2909 2910 rc = file_has_perm(current, file, 2911 file_mask_to_av(inode->i_mode, mask)); 2912 if (rc) 2913 return rc; 2914 2915 return selinux_netlbl_inode_permission(inode, mask); 2916 } 2917 2918 static int selinux_file_permission(struct file *file, int mask) 2919 { 2920 struct inode *inode = file->f_path.dentry->d_inode; 2921 struct task_security_struct *tsec = current->cred->security; 2922 struct file_security_struct *fsec = file->f_security; 2923 struct inode_security_struct *isec = inode->i_security; 2924 2925 if (!mask) { 2926 /* No permission to check. Existence test. */ 2927 return 0; 2928 } 2929 2930 if (tsec->sid == fsec->sid && fsec->isid == isec->sid 2931 && fsec->pseqno == avc_policy_seqno()) 2932 return selinux_netlbl_inode_permission(inode, mask); 2933 2934 return selinux_revalidate_file_permission(file, mask); 2935 } 2936 2937 static int selinux_file_alloc_security(struct file *file) 2938 { 2939 return file_alloc_security(file); 2940 } 2941 2942 static void selinux_file_free_security(struct file *file) 2943 { 2944 file_free_security(file); 2945 } 2946 2947 static int selinux_file_ioctl(struct file *file, unsigned int cmd, 2948 unsigned long arg) 2949 { 2950 u32 av = 0; 2951 2952 if (_IOC_DIR(cmd) & _IOC_WRITE) 2953 av |= FILE__WRITE; 2954 if (_IOC_DIR(cmd) & _IOC_READ) 2955 av |= FILE__READ; 2956 if (!av) 2957 av = FILE__IOCTL; 2958 2959 return file_has_perm(current, file, av); 2960 } 2961 2962 static int file_map_prot_check(struct file *file, unsigned long prot, int shared) 2963 { 2964 #ifndef CONFIG_PPC32 2965 if ((prot & PROT_EXEC) && (!file || (!shared && (prot & PROT_WRITE)))) { 2966 /* 2967 * We are making executable an anonymous mapping or a 2968 * private file mapping that will also be writable. 2969 * This has an additional check. 2970 */ 2971 int rc = task_has_perm(current, current, PROCESS__EXECMEM); 2972 if (rc) 2973 return rc; 2974 } 2975 #endif 2976 2977 if (file) { 2978 /* read access is always possible with a mapping */ 2979 u32 av = FILE__READ; 2980 2981 /* write access only matters if the mapping is shared */ 2982 if (shared && (prot & PROT_WRITE)) 2983 av |= FILE__WRITE; 2984 2985 if (prot & PROT_EXEC) 2986 av |= FILE__EXECUTE; 2987 2988 return file_has_perm(current, file, av); 2989 } 2990 return 0; 2991 } 2992 2993 static int selinux_file_mmap(struct file *file, unsigned long reqprot, 2994 unsigned long prot, unsigned long flags, 2995 unsigned long addr, unsigned long addr_only) 2996 { 2997 int rc = 0; 2998 u32 sid = ((struct task_security_struct *) 2999 (current->cred->security))->sid; 3000 3001 if (addr < mmap_min_addr) 3002 rc = avc_has_perm(sid, sid, SECCLASS_MEMPROTECT, 3003 MEMPROTECT__MMAP_ZERO, NULL); 3004 if (rc || addr_only) 3005 return rc; 3006 3007 if (selinux_checkreqprot) 3008 prot = reqprot; 3009 3010 return file_map_prot_check(file, prot, 3011 (flags & MAP_TYPE) == MAP_SHARED); 3012 } 3013 3014 static int selinux_file_mprotect(struct vm_area_struct *vma, 3015 unsigned long reqprot, 3016 unsigned long prot) 3017 { 3018 int rc; 3019 3020 rc = secondary_ops->file_mprotect(vma, reqprot, prot); 3021 if (rc) 3022 return rc; 3023 3024 if (selinux_checkreqprot) 3025 prot = reqprot; 3026 3027 #ifndef CONFIG_PPC32 3028 if ((prot & PROT_EXEC) && !(vma->vm_flags & VM_EXEC)) { 3029 rc = 0; 3030 if (vma->vm_start >= vma->vm_mm->start_brk && 3031 vma->vm_end <= vma->vm_mm->brk) { 3032 rc = task_has_perm(current, current, 3033 PROCESS__EXECHEAP); 3034 } else if (!vma->vm_file && 3035 vma->vm_start <= vma->vm_mm->start_stack && 3036 vma->vm_end >= vma->vm_mm->start_stack) { 3037 rc = task_has_perm(current, current, PROCESS__EXECSTACK); 3038 } else if (vma->vm_file && vma->anon_vma) { 3039 /* 3040 * We are making executable a file mapping that has 3041 * had some COW done. Since pages might have been 3042 * written, check ability to execute the possibly 3043 * modified content. This typically should only 3044 * occur for text relocations. 3045 */ 3046 rc = file_has_perm(current, vma->vm_file, 3047 FILE__EXECMOD); 3048 } 3049 if (rc) 3050 return rc; 3051 } 3052 #endif 3053 3054 return file_map_prot_check(vma->vm_file, prot, vma->vm_flags&VM_SHARED); 3055 } 3056 3057 static int selinux_file_lock(struct file *file, unsigned int cmd) 3058 { 3059 return file_has_perm(current, file, FILE__LOCK); 3060 } 3061 3062 static int selinux_file_fcntl(struct file *file, unsigned int cmd, 3063 unsigned long arg) 3064 { 3065 int err = 0; 3066 3067 switch (cmd) { 3068 case F_SETFL: 3069 if (!file->f_path.dentry || !file->f_path.dentry->d_inode) { 3070 err = -EINVAL; 3071 break; 3072 } 3073 3074 if ((file->f_flags & O_APPEND) && !(arg & O_APPEND)) { 3075 err = file_has_perm(current, file, FILE__WRITE); 3076 break; 3077 } 3078 /* fall through */ 3079 case F_SETOWN: 3080 case F_SETSIG: 3081 case F_GETFL: 3082 case F_GETOWN: 3083 case F_GETSIG: 3084 /* Just check FD__USE permission */ 3085 err = file_has_perm(current, file, 0); 3086 break; 3087 case F_GETLK: 3088 case F_SETLK: 3089 case F_SETLKW: 3090 #if BITS_PER_LONG == 32 3091 case F_GETLK64: 3092 case F_SETLK64: 3093 case F_SETLKW64: 3094 #endif 3095 if (!file->f_path.dentry || !file->f_path.dentry->d_inode) { 3096 err = -EINVAL; 3097 break; 3098 } 3099 err = file_has_perm(current, file, FILE__LOCK); 3100 break; 3101 } 3102 3103 return err; 3104 } 3105 3106 static int selinux_file_set_fowner(struct file *file) 3107 { 3108 struct task_security_struct *tsec; 3109 struct file_security_struct *fsec; 3110 3111 tsec = current->cred->security; 3112 fsec = file->f_security; 3113 fsec->fown_sid = tsec->sid; 3114 3115 return 0; 3116 } 3117 3118 static int selinux_file_send_sigiotask(struct task_struct *tsk, 3119 struct fown_struct *fown, int signum) 3120 { 3121 struct file *file; 3122 u32 perm; 3123 struct task_security_struct *tsec; 3124 struct file_security_struct *fsec; 3125 3126 /* struct fown_struct is never outside the context of a struct file */ 3127 file = container_of(fown, struct file, f_owner); 3128 3129 tsec = tsk->cred->security; 3130 fsec = file->f_security; 3131 3132 if (!signum) 3133 perm = signal_to_av(SIGIO); /* as per send_sigio_to_task */ 3134 else 3135 perm = signal_to_av(signum); 3136 3137 return avc_has_perm(fsec->fown_sid, tsec->sid, 3138 SECCLASS_PROCESS, perm, NULL); 3139 } 3140 3141 static int selinux_file_receive(struct file *file) 3142 { 3143 return file_has_perm(current, file, file_to_av(file)); 3144 } 3145 3146 static int selinux_dentry_open(struct file *file) 3147 { 3148 struct file_security_struct *fsec; 3149 struct inode *inode; 3150 struct inode_security_struct *isec; 3151 inode = file->f_path.dentry->d_inode; 3152 fsec = file->f_security; 3153 isec = inode->i_security; 3154 /* 3155 * Save inode label and policy sequence number 3156 * at open-time so that selinux_file_permission 3157 * can determine whether revalidation is necessary. 3158 * Task label is already saved in the file security 3159 * struct as its SID. 3160 */ 3161 fsec->isid = isec->sid; 3162 fsec->pseqno = avc_policy_seqno(); 3163 /* 3164 * Since the inode label or policy seqno may have changed 3165 * between the selinux_inode_permission check and the saving 3166 * of state above, recheck that access is still permitted. 3167 * Otherwise, access might never be revalidated against the 3168 * new inode label or new policy. 3169 * This check is not redundant - do not remove. 3170 */ 3171 return inode_has_perm(current, inode, open_file_to_av(file), NULL); 3172 } 3173 3174 /* task security operations */ 3175 3176 static int selinux_task_create(unsigned long clone_flags) 3177 { 3178 int rc; 3179 3180 rc = secondary_ops->task_create(clone_flags); 3181 if (rc) 3182 return rc; 3183 3184 return task_has_perm(current, current, PROCESS__FORK); 3185 } 3186 3187 static int selinux_task_alloc_security(struct task_struct *tsk) 3188 { 3189 struct task_security_struct *tsec1, *tsec2; 3190 int rc; 3191 3192 tsec1 = current->cred->security; 3193 3194 rc = task_alloc_security(tsk); 3195 if (rc) 3196 return rc; 3197 tsec2 = tsk->cred->security; 3198 3199 tsec2->osid = tsec1->osid; 3200 tsec2->sid = tsec1->sid; 3201 3202 /* Retain the exec, fs, key, and sock SIDs across fork */ 3203 tsec2->exec_sid = tsec1->exec_sid; 3204 tsec2->create_sid = tsec1->create_sid; 3205 tsec2->keycreate_sid = tsec1->keycreate_sid; 3206 tsec2->sockcreate_sid = tsec1->sockcreate_sid; 3207 3208 return 0; 3209 } 3210 3211 static void selinux_task_free_security(struct task_struct *tsk) 3212 { 3213 task_free_security(tsk); 3214 } 3215 3216 static int selinux_task_setuid(uid_t id0, uid_t id1, uid_t id2, int flags) 3217 { 3218 /* Since setuid only affects the current process, and 3219 since the SELinux controls are not based on the Linux 3220 identity attributes, SELinux does not need to control 3221 this operation. However, SELinux does control the use 3222 of the CAP_SETUID and CAP_SETGID capabilities using the 3223 capable hook. */ 3224 return 0; 3225 } 3226 3227 static int selinux_task_post_setuid(uid_t id0, uid_t id1, uid_t id2, int flags) 3228 { 3229 return secondary_ops->task_post_setuid(id0, id1, id2, flags); 3230 } 3231 3232 static int selinux_task_setgid(gid_t id0, gid_t id1, gid_t id2, int flags) 3233 { 3234 /* See the comment for setuid above. */ 3235 return 0; 3236 } 3237 3238 static int selinux_task_setpgid(struct task_struct *p, pid_t pgid) 3239 { 3240 return task_has_perm(current, p, PROCESS__SETPGID); 3241 } 3242 3243 static int selinux_task_getpgid(struct task_struct *p) 3244 { 3245 return task_has_perm(current, p, PROCESS__GETPGID); 3246 } 3247 3248 static int selinux_task_getsid(struct task_struct *p) 3249 { 3250 return task_has_perm(current, p, PROCESS__GETSESSION); 3251 } 3252 3253 static void selinux_task_getsecid(struct task_struct *p, u32 *secid) 3254 { 3255 struct task_security_struct *tsec = p->cred->security; 3256 *secid = tsec->sid; 3257 } 3258 3259 static int selinux_task_setgroups(struct group_info *group_info) 3260 { 3261 /* See the comment for setuid above. */ 3262 return 0; 3263 } 3264 3265 static int selinux_task_setnice(struct task_struct *p, int nice) 3266 { 3267 int rc; 3268 3269 rc = secondary_ops->task_setnice(p, nice); 3270 if (rc) 3271 return rc; 3272 3273 return task_has_perm(current, p, PROCESS__SETSCHED); 3274 } 3275 3276 static int selinux_task_setioprio(struct task_struct *p, int ioprio) 3277 { 3278 int rc; 3279 3280 rc = secondary_ops->task_setioprio(p, ioprio); 3281 if (rc) 3282 return rc; 3283 3284 return task_has_perm(current, p, PROCESS__SETSCHED); 3285 } 3286 3287 static int selinux_task_getioprio(struct task_struct *p) 3288 { 3289 return task_has_perm(current, p, PROCESS__GETSCHED); 3290 } 3291 3292 static int selinux_task_setrlimit(unsigned int resource, struct rlimit *new_rlim) 3293 { 3294 struct rlimit *old_rlim = current->signal->rlim + resource; 3295 int rc; 3296 3297 rc = secondary_ops->task_setrlimit(resource, new_rlim); 3298 if (rc) 3299 return rc; 3300 3301 /* Control the ability to change the hard limit (whether 3302 lowering or raising it), so that the hard limit can 3303 later be used as a safe reset point for the soft limit 3304 upon context transitions. See selinux_bprm_apply_creds. */ 3305 if (old_rlim->rlim_max != new_rlim->rlim_max) 3306 return task_has_perm(current, current, PROCESS__SETRLIMIT); 3307 3308 return 0; 3309 } 3310 3311 static int selinux_task_setscheduler(struct task_struct *p, int policy, struct sched_param *lp) 3312 { 3313 int rc; 3314 3315 rc = secondary_ops->task_setscheduler(p, policy, lp); 3316 if (rc) 3317 return rc; 3318 3319 return task_has_perm(current, p, PROCESS__SETSCHED); 3320 } 3321 3322 static int selinux_task_getscheduler(struct task_struct *p) 3323 { 3324 return task_has_perm(current, p, PROCESS__GETSCHED); 3325 } 3326 3327 static int selinux_task_movememory(struct task_struct *p) 3328 { 3329 return task_has_perm(current, p, PROCESS__SETSCHED); 3330 } 3331 3332 static int selinux_task_kill(struct task_struct *p, struct siginfo *info, 3333 int sig, u32 secid) 3334 { 3335 u32 perm; 3336 int rc; 3337 struct task_security_struct *tsec; 3338 3339 rc = secondary_ops->task_kill(p, info, sig, secid); 3340 if (rc) 3341 return rc; 3342 3343 if (!sig) 3344 perm = PROCESS__SIGNULL; /* null signal; existence test */ 3345 else 3346 perm = signal_to_av(sig); 3347 tsec = p->cred->security; 3348 if (secid) 3349 rc = avc_has_perm(secid, tsec->sid, SECCLASS_PROCESS, perm, NULL); 3350 else 3351 rc = task_has_perm(current, p, perm); 3352 return rc; 3353 } 3354 3355 static int selinux_task_prctl(int option, 3356 unsigned long arg2, 3357 unsigned long arg3, 3358 unsigned long arg4, 3359 unsigned long arg5, 3360 long *rc_p) 3361 { 3362 /* The current prctl operations do not appear to require 3363 any SELinux controls since they merely observe or modify 3364 the state of the current process. */ 3365 return secondary_ops->task_prctl(option, arg2, arg3, arg4, arg5, rc_p); 3366 } 3367 3368 static int selinux_task_wait(struct task_struct *p) 3369 { 3370 return task_has_perm(p, current, PROCESS__SIGCHLD); 3371 } 3372 3373 static void selinux_task_reparent_to_init(struct task_struct *p) 3374 { 3375 struct task_security_struct *tsec; 3376 3377 secondary_ops->task_reparent_to_init(p); 3378 3379 tsec = p->cred->security; 3380 tsec->osid = tsec->sid; 3381 tsec->sid = SECINITSID_KERNEL; 3382 return; 3383 } 3384 3385 static void selinux_task_to_inode(struct task_struct *p, 3386 struct inode *inode) 3387 { 3388 struct task_security_struct *tsec = p->cred->security; 3389 struct inode_security_struct *isec = inode->i_security; 3390 3391 isec->sid = tsec->sid; 3392 isec->initialized = 1; 3393 return; 3394 } 3395 3396 /* Returns error only if unable to parse addresses */ 3397 static int selinux_parse_skb_ipv4(struct sk_buff *skb, 3398 struct avc_audit_data *ad, u8 *proto) 3399 { 3400 int offset, ihlen, ret = -EINVAL; 3401 struct iphdr _iph, *ih; 3402 3403 offset = skb_network_offset(skb); 3404 ih = skb_header_pointer(skb, offset, sizeof(_iph), &_iph); 3405 if (ih == NULL) 3406 goto out; 3407 3408 ihlen = ih->ihl * 4; 3409 if (ihlen < sizeof(_iph)) 3410 goto out; 3411 3412 ad->u.net.v4info.saddr = ih->saddr; 3413 ad->u.net.v4info.daddr = ih->daddr; 3414 ret = 0; 3415 3416 if (proto) 3417 *proto = ih->protocol; 3418 3419 switch (ih->protocol) { 3420 case IPPROTO_TCP: { 3421 struct tcphdr _tcph, *th; 3422 3423 if (ntohs(ih->frag_off) & IP_OFFSET) 3424 break; 3425 3426 offset += ihlen; 3427 th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph); 3428 if (th == NULL) 3429 break; 3430 3431 ad->u.net.sport = th->source; 3432 ad->u.net.dport = th->dest; 3433 break; 3434 } 3435 3436 case IPPROTO_UDP: { 3437 struct udphdr _udph, *uh; 3438 3439 if (ntohs(ih->frag_off) & IP_OFFSET) 3440 break; 3441 3442 offset += ihlen; 3443 uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph); 3444 if (uh == NULL) 3445 break; 3446 3447 ad->u.net.sport = uh->source; 3448 ad->u.net.dport = uh->dest; 3449 break; 3450 } 3451 3452 case IPPROTO_DCCP: { 3453 struct dccp_hdr _dccph, *dh; 3454 3455 if (ntohs(ih->frag_off) & IP_OFFSET) 3456 break; 3457 3458 offset += ihlen; 3459 dh = skb_header_pointer(skb, offset, sizeof(_dccph), &_dccph); 3460 if (dh == NULL) 3461 break; 3462 3463 ad->u.net.sport = dh->dccph_sport; 3464 ad->u.net.dport = dh->dccph_dport; 3465 break; 3466 } 3467 3468 default: 3469 break; 3470 } 3471 out: 3472 return ret; 3473 } 3474 3475 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE) 3476 3477 /* Returns error only if unable to parse addresses */ 3478 static int selinux_parse_skb_ipv6(struct sk_buff *skb, 3479 struct avc_audit_data *ad, u8 *proto) 3480 { 3481 u8 nexthdr; 3482 int ret = -EINVAL, offset; 3483 struct ipv6hdr _ipv6h, *ip6; 3484 3485 offset = skb_network_offset(skb); 3486 ip6 = skb_header_pointer(skb, offset, sizeof(_ipv6h), &_ipv6h); 3487 if (ip6 == NULL) 3488 goto out; 3489 3490 ipv6_addr_copy(&ad->u.net.v6info.saddr, &ip6->saddr); 3491 ipv6_addr_copy(&ad->u.net.v6info.daddr, &ip6->daddr); 3492 ret = 0; 3493 3494 nexthdr = ip6->nexthdr; 3495 offset += sizeof(_ipv6h); 3496 offset = ipv6_skip_exthdr(skb, offset, &nexthdr); 3497 if (offset < 0) 3498 goto out; 3499 3500 if (proto) 3501 *proto = nexthdr; 3502 3503 switch (nexthdr) { 3504 case IPPROTO_TCP: { 3505 struct tcphdr _tcph, *th; 3506 3507 th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph); 3508 if (th == NULL) 3509 break; 3510 3511 ad->u.net.sport = th->source; 3512 ad->u.net.dport = th->dest; 3513 break; 3514 } 3515 3516 case IPPROTO_UDP: { 3517 struct udphdr _udph, *uh; 3518 3519 uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph); 3520 if (uh == NULL) 3521 break; 3522 3523 ad->u.net.sport = uh->source; 3524 ad->u.net.dport = uh->dest; 3525 break; 3526 } 3527 3528 case IPPROTO_DCCP: { 3529 struct dccp_hdr _dccph, *dh; 3530 3531 dh = skb_header_pointer(skb, offset, sizeof(_dccph), &_dccph); 3532 if (dh == NULL) 3533 break; 3534 3535 ad->u.net.sport = dh->dccph_sport; 3536 ad->u.net.dport = dh->dccph_dport; 3537 break; 3538 } 3539 3540 /* includes fragments */ 3541 default: 3542 break; 3543 } 3544 out: 3545 return ret; 3546 } 3547 3548 #endif /* IPV6 */ 3549 3550 static int selinux_parse_skb(struct sk_buff *skb, struct avc_audit_data *ad, 3551 char **_addrp, int src, u8 *proto) 3552 { 3553 char *addrp; 3554 int ret; 3555 3556 switch (ad->u.net.family) { 3557 case PF_INET: 3558 ret = selinux_parse_skb_ipv4(skb, ad, proto); 3559 if (ret) 3560 goto parse_error; 3561 addrp = (char *)(src ? &ad->u.net.v4info.saddr : 3562 &ad->u.net.v4info.daddr); 3563 goto okay; 3564 3565 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE) 3566 case PF_INET6: 3567 ret = selinux_parse_skb_ipv6(skb, ad, proto); 3568 if (ret) 3569 goto parse_error; 3570 addrp = (char *)(src ? &ad->u.net.v6info.saddr : 3571 &ad->u.net.v6info.daddr); 3572 goto okay; 3573 #endif /* IPV6 */ 3574 default: 3575 addrp = NULL; 3576 goto okay; 3577 } 3578 3579 parse_error: 3580 printk(KERN_WARNING 3581 "SELinux: failure in selinux_parse_skb()," 3582 " unable to parse packet\n"); 3583 return ret; 3584 3585 okay: 3586 if (_addrp) 3587 *_addrp = addrp; 3588 return 0; 3589 } 3590 3591 /** 3592 * selinux_skb_peerlbl_sid - Determine the peer label of a packet 3593 * @skb: the packet 3594 * @family: protocol family 3595 * @sid: the packet's peer label SID 3596 * 3597 * Description: 3598 * Check the various different forms of network peer labeling and determine 3599 * the peer label/SID for the packet; most of the magic actually occurs in 3600 * the security server function security_net_peersid_cmp(). The function 3601 * returns zero if the value in @sid is valid (although it may be SECSID_NULL) 3602 * or -EACCES if @sid is invalid due to inconsistencies with the different 3603 * peer labels. 3604 * 3605 */ 3606 static int selinux_skb_peerlbl_sid(struct sk_buff *skb, u16 family, u32 *sid) 3607 { 3608 int err; 3609 u32 xfrm_sid; 3610 u32 nlbl_sid; 3611 u32 nlbl_type; 3612 3613 selinux_skb_xfrm_sid(skb, &xfrm_sid); 3614 selinux_netlbl_skbuff_getsid(skb, family, &nlbl_type, &nlbl_sid); 3615 3616 err = security_net_peersid_resolve(nlbl_sid, nlbl_type, xfrm_sid, sid); 3617 if (unlikely(err)) { 3618 printk(KERN_WARNING 3619 "SELinux: failure in selinux_skb_peerlbl_sid()," 3620 " unable to determine packet's peer label\n"); 3621 return -EACCES; 3622 } 3623 3624 return 0; 3625 } 3626 3627 /* socket security operations */ 3628 static int socket_has_perm(struct task_struct *task, struct socket *sock, 3629 u32 perms) 3630 { 3631 struct inode_security_struct *isec; 3632 struct task_security_struct *tsec; 3633 struct avc_audit_data ad; 3634 int err = 0; 3635 3636 tsec = task->cred->security; 3637 isec = SOCK_INODE(sock)->i_security; 3638 3639 if (isec->sid == SECINITSID_KERNEL) 3640 goto out; 3641 3642 AVC_AUDIT_DATA_INIT(&ad, NET); 3643 ad.u.net.sk = sock->sk; 3644 err = avc_has_perm(tsec->sid, isec->sid, isec->sclass, perms, &ad); 3645 3646 out: 3647 return err; 3648 } 3649 3650 static int selinux_socket_create(int family, int type, 3651 int protocol, int kern) 3652 { 3653 int err = 0; 3654 struct task_security_struct *tsec; 3655 u32 newsid; 3656 3657 if (kern) 3658 goto out; 3659 3660 tsec = current->cred->security; 3661 newsid = tsec->sockcreate_sid ? : tsec->sid; 3662 err = avc_has_perm(tsec->sid, newsid, 3663 socket_type_to_security_class(family, type, 3664 protocol), SOCKET__CREATE, NULL); 3665 3666 out: 3667 return err; 3668 } 3669 3670 static int selinux_socket_post_create(struct socket *sock, int family, 3671 int type, int protocol, int kern) 3672 { 3673 int err = 0; 3674 struct inode_security_struct *isec; 3675 struct task_security_struct *tsec; 3676 struct sk_security_struct *sksec; 3677 u32 newsid; 3678 3679 isec = SOCK_INODE(sock)->i_security; 3680 3681 tsec = current->cred->security; 3682 newsid = tsec->sockcreate_sid ? : tsec->sid; 3683 isec->sclass = socket_type_to_security_class(family, type, protocol); 3684 isec->sid = kern ? SECINITSID_KERNEL : newsid; 3685 isec->initialized = 1; 3686 3687 if (sock->sk) { 3688 sksec = sock->sk->sk_security; 3689 sksec->sid = isec->sid; 3690 sksec->sclass = isec->sclass; 3691 err = selinux_netlbl_socket_post_create(sock); 3692 } 3693 3694 return err; 3695 } 3696 3697 /* Range of port numbers used to automatically bind. 3698 Need to determine whether we should perform a name_bind 3699 permission check between the socket and the port number. */ 3700 3701 static int selinux_socket_bind(struct socket *sock, struct sockaddr *address, int addrlen) 3702 { 3703 u16 family; 3704 int err; 3705 3706 err = socket_has_perm(current, sock, SOCKET__BIND); 3707 if (err) 3708 goto out; 3709 3710 /* 3711 * If PF_INET or PF_INET6, check name_bind permission for the port. 3712 * Multiple address binding for SCTP is not supported yet: we just 3713 * check the first address now. 3714 */ 3715 family = sock->sk->sk_family; 3716 if (family == PF_INET || family == PF_INET6) { 3717 char *addrp; 3718 struct inode_security_struct *isec; 3719 struct task_security_struct *tsec; 3720 struct avc_audit_data ad; 3721 struct sockaddr_in *addr4 = NULL; 3722 struct sockaddr_in6 *addr6 = NULL; 3723 unsigned short snum; 3724 struct sock *sk = sock->sk; 3725 u32 sid, node_perm; 3726 3727 tsec = current->cred->security; 3728 isec = SOCK_INODE(sock)->i_security; 3729 3730 if (family == PF_INET) { 3731 addr4 = (struct sockaddr_in *)address; 3732 snum = ntohs(addr4->sin_port); 3733 addrp = (char *)&addr4->sin_addr.s_addr; 3734 } else { 3735 addr6 = (struct sockaddr_in6 *)address; 3736 snum = ntohs(addr6->sin6_port); 3737 addrp = (char *)&addr6->sin6_addr.s6_addr; 3738 } 3739 3740 if (snum) { 3741 int low, high; 3742 3743 inet_get_local_port_range(&low, &high); 3744 3745 if (snum < max(PROT_SOCK, low) || snum > high) { 3746 err = sel_netport_sid(sk->sk_protocol, 3747 snum, &sid); 3748 if (err) 3749 goto out; 3750 AVC_AUDIT_DATA_INIT(&ad, NET); 3751 ad.u.net.sport = htons(snum); 3752 ad.u.net.family = family; 3753 err = avc_has_perm(isec->sid, sid, 3754 isec->sclass, 3755 SOCKET__NAME_BIND, &ad); 3756 if (err) 3757 goto out; 3758 } 3759 } 3760 3761 switch (isec->sclass) { 3762 case SECCLASS_TCP_SOCKET: 3763 node_perm = TCP_SOCKET__NODE_BIND; 3764 break; 3765 3766 case SECCLASS_UDP_SOCKET: 3767 node_perm = UDP_SOCKET__NODE_BIND; 3768 break; 3769 3770 case SECCLASS_DCCP_SOCKET: 3771 node_perm = DCCP_SOCKET__NODE_BIND; 3772 break; 3773 3774 default: 3775 node_perm = RAWIP_SOCKET__NODE_BIND; 3776 break; 3777 } 3778 3779 err = sel_netnode_sid(addrp, family, &sid); 3780 if (err) 3781 goto out; 3782 3783 AVC_AUDIT_DATA_INIT(&ad, NET); 3784 ad.u.net.sport = htons(snum); 3785 ad.u.net.family = family; 3786 3787 if (family == PF_INET) 3788 ad.u.net.v4info.saddr = addr4->sin_addr.s_addr; 3789 else 3790 ipv6_addr_copy(&ad.u.net.v6info.saddr, &addr6->sin6_addr); 3791 3792 err = avc_has_perm(isec->sid, sid, 3793 isec->sclass, node_perm, &ad); 3794 if (err) 3795 goto out; 3796 } 3797 out: 3798 return err; 3799 } 3800 3801 static int selinux_socket_connect(struct socket *sock, struct sockaddr *address, int addrlen) 3802 { 3803 struct sock *sk = sock->sk; 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 avc_audit_data ad; 3818 struct sockaddr_in *addr4 = NULL; 3819 struct sockaddr_in6 *addr6 = NULL; 3820 unsigned short snum; 3821 u32 sid, perm; 3822 3823 if (sk->sk_family == PF_INET) { 3824 addr4 = (struct sockaddr_in *)address; 3825 if (addrlen < sizeof(struct sockaddr_in)) 3826 return -EINVAL; 3827 snum = ntohs(addr4->sin_port); 3828 } else { 3829 addr6 = (struct sockaddr_in6 *)address; 3830 if (addrlen < SIN6_LEN_RFC2133) 3831 return -EINVAL; 3832 snum = ntohs(addr6->sin6_port); 3833 } 3834 3835 err = sel_netport_sid(sk->sk_protocol, snum, &sid); 3836 if (err) 3837 goto out; 3838 3839 perm = (isec->sclass == SECCLASS_TCP_SOCKET) ? 3840 TCP_SOCKET__NAME_CONNECT : DCCP_SOCKET__NAME_CONNECT; 3841 3842 AVC_AUDIT_DATA_INIT(&ad, NET); 3843 ad.u.net.dport = htons(snum); 3844 ad.u.net.family = sk->sk_family; 3845 err = avc_has_perm(isec->sid, sid, isec->sclass, perm, &ad); 3846 if (err) 3847 goto out; 3848 } 3849 3850 err = selinux_netlbl_socket_connect(sk, address); 3851 3852 out: 3853 return err; 3854 } 3855 3856 static int selinux_socket_listen(struct socket *sock, int backlog) 3857 { 3858 return socket_has_perm(current, sock, SOCKET__LISTEN); 3859 } 3860 3861 static int selinux_socket_accept(struct socket *sock, struct socket *newsock) 3862 { 3863 int err; 3864 struct inode_security_struct *isec; 3865 struct inode_security_struct *newisec; 3866 3867 err = socket_has_perm(current, sock, SOCKET__ACCEPT); 3868 if (err) 3869 return err; 3870 3871 newisec = SOCK_INODE(newsock)->i_security; 3872 3873 isec = SOCK_INODE(sock)->i_security; 3874 newisec->sclass = isec->sclass; 3875 newisec->sid = isec->sid; 3876 newisec->initialized = 1; 3877 3878 return 0; 3879 } 3880 3881 static int selinux_socket_sendmsg(struct socket *sock, struct msghdr *msg, 3882 int size) 3883 { 3884 int rc; 3885 3886 rc = socket_has_perm(current, sock, SOCKET__WRITE); 3887 if (rc) 3888 return rc; 3889 3890 return selinux_netlbl_inode_permission(SOCK_INODE(sock), MAY_WRITE); 3891 } 3892 3893 static int selinux_socket_recvmsg(struct socket *sock, struct msghdr *msg, 3894 int size, int flags) 3895 { 3896 return socket_has_perm(current, sock, SOCKET__READ); 3897 } 3898 3899 static int selinux_socket_getsockname(struct socket *sock) 3900 { 3901 return socket_has_perm(current, sock, SOCKET__GETATTR); 3902 } 3903 3904 static int selinux_socket_getpeername(struct socket *sock) 3905 { 3906 return socket_has_perm(current, sock, SOCKET__GETATTR); 3907 } 3908 3909 static int selinux_socket_setsockopt(struct socket *sock, int level, int optname) 3910 { 3911 int err; 3912 3913 err = socket_has_perm(current, sock, SOCKET__SETOPT); 3914 if (err) 3915 return err; 3916 3917 return selinux_netlbl_socket_setsockopt(sock, level, optname); 3918 } 3919 3920 static int selinux_socket_getsockopt(struct socket *sock, int level, 3921 int optname) 3922 { 3923 return socket_has_perm(current, sock, SOCKET__GETOPT); 3924 } 3925 3926 static int selinux_socket_shutdown(struct socket *sock, int how) 3927 { 3928 return socket_has_perm(current, sock, SOCKET__SHUTDOWN); 3929 } 3930 3931 static int selinux_socket_unix_stream_connect(struct socket *sock, 3932 struct socket *other, 3933 struct sock *newsk) 3934 { 3935 struct sk_security_struct *ssec; 3936 struct inode_security_struct *isec; 3937 struct inode_security_struct *other_isec; 3938 struct avc_audit_data ad; 3939 int err; 3940 3941 err = secondary_ops->unix_stream_connect(sock, other, newsk); 3942 if (err) 3943 return err; 3944 3945 isec = SOCK_INODE(sock)->i_security; 3946 other_isec = SOCK_INODE(other)->i_security; 3947 3948 AVC_AUDIT_DATA_INIT(&ad, NET); 3949 ad.u.net.sk = other->sk; 3950 3951 err = avc_has_perm(isec->sid, other_isec->sid, 3952 isec->sclass, 3953 UNIX_STREAM_SOCKET__CONNECTTO, &ad); 3954 if (err) 3955 return err; 3956 3957 /* connecting socket */ 3958 ssec = sock->sk->sk_security; 3959 ssec->peer_sid = other_isec->sid; 3960 3961 /* server child socket */ 3962 ssec = newsk->sk_security; 3963 ssec->peer_sid = isec->sid; 3964 err = security_sid_mls_copy(other_isec->sid, ssec->peer_sid, &ssec->sid); 3965 3966 return err; 3967 } 3968 3969 static int selinux_socket_unix_may_send(struct socket *sock, 3970 struct socket *other) 3971 { 3972 struct inode_security_struct *isec; 3973 struct inode_security_struct *other_isec; 3974 struct avc_audit_data ad; 3975 int err; 3976 3977 isec = SOCK_INODE(sock)->i_security; 3978 other_isec = SOCK_INODE(other)->i_security; 3979 3980 AVC_AUDIT_DATA_INIT(&ad, NET); 3981 ad.u.net.sk = other->sk; 3982 3983 err = avc_has_perm(isec->sid, other_isec->sid, 3984 isec->sclass, SOCKET__SENDTO, &ad); 3985 if (err) 3986 return err; 3987 3988 return 0; 3989 } 3990 3991 static int selinux_inet_sys_rcv_skb(int ifindex, char *addrp, u16 family, 3992 u32 peer_sid, 3993 struct avc_audit_data *ad) 3994 { 3995 int err; 3996 u32 if_sid; 3997 u32 node_sid; 3998 3999 err = sel_netif_sid(ifindex, &if_sid); 4000 if (err) 4001 return err; 4002 err = avc_has_perm(peer_sid, if_sid, 4003 SECCLASS_NETIF, NETIF__INGRESS, ad); 4004 if (err) 4005 return err; 4006 4007 err = sel_netnode_sid(addrp, family, &node_sid); 4008 if (err) 4009 return err; 4010 return avc_has_perm(peer_sid, node_sid, 4011 SECCLASS_NODE, NODE__RECVFROM, ad); 4012 } 4013 4014 static int selinux_sock_rcv_skb_iptables_compat(struct sock *sk, 4015 struct sk_buff *skb, 4016 struct avc_audit_data *ad, 4017 u16 family, 4018 char *addrp) 4019 { 4020 int err; 4021 struct sk_security_struct *sksec = sk->sk_security; 4022 u16 sk_class; 4023 u32 netif_perm, node_perm, recv_perm; 4024 u32 port_sid, node_sid, if_sid, sk_sid; 4025 4026 sk_sid = sksec->sid; 4027 sk_class = sksec->sclass; 4028 4029 switch (sk_class) { 4030 case SECCLASS_UDP_SOCKET: 4031 netif_perm = NETIF__UDP_RECV; 4032 node_perm = NODE__UDP_RECV; 4033 recv_perm = UDP_SOCKET__RECV_MSG; 4034 break; 4035 case SECCLASS_TCP_SOCKET: 4036 netif_perm = NETIF__TCP_RECV; 4037 node_perm = NODE__TCP_RECV; 4038 recv_perm = TCP_SOCKET__RECV_MSG; 4039 break; 4040 case SECCLASS_DCCP_SOCKET: 4041 netif_perm = NETIF__DCCP_RECV; 4042 node_perm = NODE__DCCP_RECV; 4043 recv_perm = DCCP_SOCKET__RECV_MSG; 4044 break; 4045 default: 4046 netif_perm = NETIF__RAWIP_RECV; 4047 node_perm = NODE__RAWIP_RECV; 4048 recv_perm = 0; 4049 break; 4050 } 4051 4052 err = sel_netif_sid(skb->iif, &if_sid); 4053 if (err) 4054 return err; 4055 err = avc_has_perm(sk_sid, if_sid, SECCLASS_NETIF, netif_perm, ad); 4056 if (err) 4057 return err; 4058 4059 err = sel_netnode_sid(addrp, family, &node_sid); 4060 if (err) 4061 return err; 4062 err = avc_has_perm(sk_sid, node_sid, SECCLASS_NODE, node_perm, ad); 4063 if (err) 4064 return err; 4065 4066 if (!recv_perm) 4067 return 0; 4068 err = sel_netport_sid(sk->sk_protocol, 4069 ntohs(ad->u.net.sport), &port_sid); 4070 if (unlikely(err)) { 4071 printk(KERN_WARNING 4072 "SELinux: failure in" 4073 " selinux_sock_rcv_skb_iptables_compat()," 4074 " network port label not found\n"); 4075 return err; 4076 } 4077 return avc_has_perm(sk_sid, port_sid, sk_class, recv_perm, ad); 4078 } 4079 4080 static int selinux_sock_rcv_skb_compat(struct sock *sk, struct sk_buff *skb, 4081 u16 family) 4082 { 4083 int err; 4084 struct sk_security_struct *sksec = sk->sk_security; 4085 u32 peer_sid; 4086 u32 sk_sid = sksec->sid; 4087 struct avc_audit_data ad; 4088 char *addrp; 4089 4090 AVC_AUDIT_DATA_INIT(&ad, NET); 4091 ad.u.net.netif = skb->iif; 4092 ad.u.net.family = family; 4093 err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL); 4094 if (err) 4095 return err; 4096 4097 if (selinux_compat_net) 4098 err = selinux_sock_rcv_skb_iptables_compat(sk, skb, &ad, 4099 family, addrp); 4100 else 4101 err = avc_has_perm(sk_sid, skb->secmark, SECCLASS_PACKET, 4102 PACKET__RECV, &ad); 4103 if (err) 4104 return err; 4105 4106 if (selinux_policycap_netpeer) { 4107 err = selinux_skb_peerlbl_sid(skb, family, &peer_sid); 4108 if (err) 4109 return err; 4110 err = avc_has_perm(sk_sid, peer_sid, 4111 SECCLASS_PEER, PEER__RECV, &ad); 4112 if (err) 4113 selinux_netlbl_err(skb, err, 0); 4114 } else { 4115 err = selinux_netlbl_sock_rcv_skb(sksec, skb, family, &ad); 4116 if (err) 4117 return err; 4118 err = selinux_xfrm_sock_rcv_skb(sksec->sid, skb, &ad); 4119 } 4120 4121 return err; 4122 } 4123 4124 static int selinux_socket_sock_rcv_skb(struct sock *sk, struct sk_buff *skb) 4125 { 4126 int err; 4127 struct sk_security_struct *sksec = sk->sk_security; 4128 u16 family = sk->sk_family; 4129 u32 sk_sid = sksec->sid; 4130 struct avc_audit_data ad; 4131 char *addrp; 4132 u8 secmark_active; 4133 u8 peerlbl_active; 4134 4135 if (family != PF_INET && family != PF_INET6) 4136 return 0; 4137 4138 /* Handle mapped IPv4 packets arriving via IPv6 sockets */ 4139 if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP)) 4140 family = PF_INET; 4141 4142 /* If any sort of compatibility mode is enabled then handoff processing 4143 * to the selinux_sock_rcv_skb_compat() function to deal with the 4144 * special handling. We do this in an attempt to keep this function 4145 * as fast and as clean as possible. */ 4146 if (selinux_compat_net || !selinux_policycap_netpeer) 4147 return selinux_sock_rcv_skb_compat(sk, skb, family); 4148 4149 secmark_active = selinux_secmark_enabled(); 4150 peerlbl_active = netlbl_enabled() || selinux_xfrm_enabled(); 4151 if (!secmark_active && !peerlbl_active) 4152 return 0; 4153 4154 AVC_AUDIT_DATA_INIT(&ad, NET); 4155 ad.u.net.netif = skb->iif; 4156 ad.u.net.family = family; 4157 err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL); 4158 if (err) 4159 return err; 4160 4161 if (peerlbl_active) { 4162 u32 peer_sid; 4163 4164 err = selinux_skb_peerlbl_sid(skb, family, &peer_sid); 4165 if (err) 4166 return err; 4167 err = selinux_inet_sys_rcv_skb(skb->iif, addrp, family, 4168 peer_sid, &ad); 4169 if (err) { 4170 selinux_netlbl_err(skb, err, 0); 4171 return err; 4172 } 4173 err = avc_has_perm(sk_sid, peer_sid, SECCLASS_PEER, 4174 PEER__RECV, &ad); 4175 if (err) 4176 selinux_netlbl_err(skb, err, 0); 4177 } 4178 4179 if (secmark_active) { 4180 err = avc_has_perm(sk_sid, skb->secmark, SECCLASS_PACKET, 4181 PACKET__RECV, &ad); 4182 if (err) 4183 return err; 4184 } 4185 4186 return err; 4187 } 4188 4189 static int selinux_socket_getpeersec_stream(struct socket *sock, char __user *optval, 4190 int __user *optlen, unsigned len) 4191 { 4192 int err = 0; 4193 char *scontext; 4194 u32 scontext_len; 4195 struct sk_security_struct *ssec; 4196 struct inode_security_struct *isec; 4197 u32 peer_sid = SECSID_NULL; 4198 4199 isec = SOCK_INODE(sock)->i_security; 4200 4201 if (isec->sclass == SECCLASS_UNIX_STREAM_SOCKET || 4202 isec->sclass == SECCLASS_TCP_SOCKET) { 4203 ssec = sock->sk->sk_security; 4204 peer_sid = ssec->peer_sid; 4205 } 4206 if (peer_sid == SECSID_NULL) { 4207 err = -ENOPROTOOPT; 4208 goto out; 4209 } 4210 4211 err = security_sid_to_context(peer_sid, &scontext, &scontext_len); 4212 4213 if (err) 4214 goto out; 4215 4216 if (scontext_len > len) { 4217 err = -ERANGE; 4218 goto out_len; 4219 } 4220 4221 if (copy_to_user(optval, scontext, scontext_len)) 4222 err = -EFAULT; 4223 4224 out_len: 4225 if (put_user(scontext_len, optlen)) 4226 err = -EFAULT; 4227 4228 kfree(scontext); 4229 out: 4230 return err; 4231 } 4232 4233 static int selinux_socket_getpeersec_dgram(struct socket *sock, struct sk_buff *skb, u32 *secid) 4234 { 4235 u32 peer_secid = SECSID_NULL; 4236 u16 family; 4237 4238 if (skb && skb->protocol == htons(ETH_P_IP)) 4239 family = PF_INET; 4240 else if (skb && skb->protocol == htons(ETH_P_IPV6)) 4241 family = PF_INET6; 4242 else if (sock) 4243 family = sock->sk->sk_family; 4244 else 4245 goto out; 4246 4247 if (sock && family == PF_UNIX) 4248 selinux_inode_getsecid(SOCK_INODE(sock), &peer_secid); 4249 else if (skb) 4250 selinux_skb_peerlbl_sid(skb, family, &peer_secid); 4251 4252 out: 4253 *secid = peer_secid; 4254 if (peer_secid == SECSID_NULL) 4255 return -EINVAL; 4256 return 0; 4257 } 4258 4259 static int selinux_sk_alloc_security(struct sock *sk, int family, gfp_t priority) 4260 { 4261 return sk_alloc_security(sk, family, priority); 4262 } 4263 4264 static void selinux_sk_free_security(struct sock *sk) 4265 { 4266 sk_free_security(sk); 4267 } 4268 4269 static void selinux_sk_clone_security(const struct sock *sk, struct sock *newsk) 4270 { 4271 struct sk_security_struct *ssec = sk->sk_security; 4272 struct sk_security_struct *newssec = newsk->sk_security; 4273 4274 newssec->sid = ssec->sid; 4275 newssec->peer_sid = ssec->peer_sid; 4276 newssec->sclass = ssec->sclass; 4277 4278 selinux_netlbl_sk_security_reset(newssec, newsk->sk_family); 4279 } 4280 4281 static void selinux_sk_getsecid(struct sock *sk, u32 *secid) 4282 { 4283 if (!sk) 4284 *secid = SECINITSID_ANY_SOCKET; 4285 else { 4286 struct sk_security_struct *sksec = sk->sk_security; 4287 4288 *secid = sksec->sid; 4289 } 4290 } 4291 4292 static void selinux_sock_graft(struct sock *sk, struct socket *parent) 4293 { 4294 struct inode_security_struct *isec = SOCK_INODE(parent)->i_security; 4295 struct sk_security_struct *sksec = sk->sk_security; 4296 4297 if (sk->sk_family == PF_INET || sk->sk_family == PF_INET6 || 4298 sk->sk_family == PF_UNIX) 4299 isec->sid = sksec->sid; 4300 sksec->sclass = isec->sclass; 4301 } 4302 4303 static int selinux_inet_conn_request(struct sock *sk, struct sk_buff *skb, 4304 struct request_sock *req) 4305 { 4306 struct sk_security_struct *sksec = sk->sk_security; 4307 int err; 4308 u16 family = sk->sk_family; 4309 u32 newsid; 4310 u32 peersid; 4311 4312 /* handle mapped IPv4 packets arriving via IPv6 sockets */ 4313 if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP)) 4314 family = PF_INET; 4315 4316 err = selinux_skb_peerlbl_sid(skb, family, &peersid); 4317 if (err) 4318 return err; 4319 if (peersid == SECSID_NULL) { 4320 req->secid = sksec->sid; 4321 req->peer_secid = SECSID_NULL; 4322 return 0; 4323 } 4324 4325 err = security_sid_mls_copy(sksec->sid, peersid, &newsid); 4326 if (err) 4327 return err; 4328 4329 req->secid = newsid; 4330 req->peer_secid = peersid; 4331 return 0; 4332 } 4333 4334 static void selinux_inet_csk_clone(struct sock *newsk, 4335 const struct request_sock *req) 4336 { 4337 struct sk_security_struct *newsksec = newsk->sk_security; 4338 4339 newsksec->sid = req->secid; 4340 newsksec->peer_sid = req->peer_secid; 4341 /* NOTE: Ideally, we should also get the isec->sid for the 4342 new socket in sync, but we don't have the isec available yet. 4343 So we will wait until sock_graft to do it, by which 4344 time it will have been created and available. */ 4345 4346 /* We don't need to take any sort of lock here as we are the only 4347 * thread with access to newsksec */ 4348 selinux_netlbl_sk_security_reset(newsksec, req->rsk_ops->family); 4349 } 4350 4351 static void selinux_inet_conn_established(struct sock *sk, struct sk_buff *skb) 4352 { 4353 u16 family = sk->sk_family; 4354 struct sk_security_struct *sksec = sk->sk_security; 4355 4356 /* handle mapped IPv4 packets arriving via IPv6 sockets */ 4357 if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP)) 4358 family = PF_INET; 4359 4360 selinux_skb_peerlbl_sid(skb, family, &sksec->peer_sid); 4361 4362 selinux_netlbl_inet_conn_established(sk, family); 4363 } 4364 4365 static void selinux_req_classify_flow(const struct request_sock *req, 4366 struct flowi *fl) 4367 { 4368 fl->secid = req->secid; 4369 } 4370 4371 static int selinux_nlmsg_perm(struct sock *sk, struct sk_buff *skb) 4372 { 4373 int err = 0; 4374 u32 perm; 4375 struct nlmsghdr *nlh; 4376 struct socket *sock = sk->sk_socket; 4377 struct inode_security_struct *isec = SOCK_INODE(sock)->i_security; 4378 4379 if (skb->len < NLMSG_SPACE(0)) { 4380 err = -EINVAL; 4381 goto out; 4382 } 4383 nlh = nlmsg_hdr(skb); 4384 4385 err = selinux_nlmsg_lookup(isec->sclass, nlh->nlmsg_type, &perm); 4386 if (err) { 4387 if (err == -EINVAL) { 4388 audit_log(current->audit_context, GFP_KERNEL, AUDIT_SELINUX_ERR, 4389 "SELinux: unrecognized netlink message" 4390 " type=%hu for sclass=%hu\n", 4391 nlh->nlmsg_type, isec->sclass); 4392 if (!selinux_enforcing || security_get_allow_unknown()) 4393 err = 0; 4394 } 4395 4396 /* Ignore */ 4397 if (err == -ENOENT) 4398 err = 0; 4399 goto out; 4400 } 4401 4402 err = socket_has_perm(current, sock, perm); 4403 out: 4404 return err; 4405 } 4406 4407 #ifdef CONFIG_NETFILTER 4408 4409 static unsigned int selinux_ip_forward(struct sk_buff *skb, int ifindex, 4410 u16 family) 4411 { 4412 int err; 4413 char *addrp; 4414 u32 peer_sid; 4415 struct avc_audit_data ad; 4416 u8 secmark_active; 4417 u8 netlbl_active; 4418 u8 peerlbl_active; 4419 4420 if (!selinux_policycap_netpeer) 4421 return NF_ACCEPT; 4422 4423 secmark_active = selinux_secmark_enabled(); 4424 netlbl_active = netlbl_enabled(); 4425 peerlbl_active = netlbl_active || selinux_xfrm_enabled(); 4426 if (!secmark_active && !peerlbl_active) 4427 return NF_ACCEPT; 4428 4429 if (selinux_skb_peerlbl_sid(skb, family, &peer_sid) != 0) 4430 return NF_DROP; 4431 4432 AVC_AUDIT_DATA_INIT(&ad, NET); 4433 ad.u.net.netif = ifindex; 4434 ad.u.net.family = family; 4435 if (selinux_parse_skb(skb, &ad, &addrp, 1, NULL) != 0) 4436 return NF_DROP; 4437 4438 if (peerlbl_active) { 4439 err = selinux_inet_sys_rcv_skb(ifindex, addrp, family, 4440 peer_sid, &ad); 4441 if (err) { 4442 selinux_netlbl_err(skb, err, 1); 4443 return NF_DROP; 4444 } 4445 } 4446 4447 if (secmark_active) 4448 if (avc_has_perm(peer_sid, skb->secmark, 4449 SECCLASS_PACKET, PACKET__FORWARD_IN, &ad)) 4450 return NF_DROP; 4451 4452 if (netlbl_active) 4453 /* we do this in the FORWARD path and not the POST_ROUTING 4454 * path because we want to make sure we apply the necessary 4455 * labeling before IPsec is applied so we can leverage AH 4456 * protection */ 4457 if (selinux_netlbl_skbuff_setsid(skb, family, peer_sid) != 0) 4458 return NF_DROP; 4459 4460 return NF_ACCEPT; 4461 } 4462 4463 static unsigned int selinux_ipv4_forward(unsigned int hooknum, 4464 struct sk_buff *skb, 4465 const struct net_device *in, 4466 const struct net_device *out, 4467 int (*okfn)(struct sk_buff *)) 4468 { 4469 return selinux_ip_forward(skb, in->ifindex, PF_INET); 4470 } 4471 4472 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE) 4473 static unsigned int selinux_ipv6_forward(unsigned int hooknum, 4474 struct sk_buff *skb, 4475 const struct net_device *in, 4476 const struct net_device *out, 4477 int (*okfn)(struct sk_buff *)) 4478 { 4479 return selinux_ip_forward(skb, in->ifindex, PF_INET6); 4480 } 4481 #endif /* IPV6 */ 4482 4483 static unsigned int selinux_ip_output(struct sk_buff *skb, 4484 u16 family) 4485 { 4486 u32 sid; 4487 4488 if (!netlbl_enabled()) 4489 return NF_ACCEPT; 4490 4491 /* we do this in the LOCAL_OUT path and not the POST_ROUTING path 4492 * because we want to make sure we apply the necessary labeling 4493 * before IPsec is applied so we can leverage AH protection */ 4494 if (skb->sk) { 4495 struct sk_security_struct *sksec = skb->sk->sk_security; 4496 sid = sksec->sid; 4497 } else 4498 sid = SECINITSID_KERNEL; 4499 if (selinux_netlbl_skbuff_setsid(skb, family, sid) != 0) 4500 return NF_DROP; 4501 4502 return NF_ACCEPT; 4503 } 4504 4505 static unsigned int selinux_ipv4_output(unsigned int hooknum, 4506 struct sk_buff *skb, 4507 const struct net_device *in, 4508 const struct net_device *out, 4509 int (*okfn)(struct sk_buff *)) 4510 { 4511 return selinux_ip_output(skb, PF_INET); 4512 } 4513 4514 static int selinux_ip_postroute_iptables_compat(struct sock *sk, 4515 int ifindex, 4516 struct avc_audit_data *ad, 4517 u16 family, char *addrp) 4518 { 4519 int err; 4520 struct sk_security_struct *sksec = sk->sk_security; 4521 u16 sk_class; 4522 u32 netif_perm, node_perm, send_perm; 4523 u32 port_sid, node_sid, if_sid, sk_sid; 4524 4525 sk_sid = sksec->sid; 4526 sk_class = sksec->sclass; 4527 4528 switch (sk_class) { 4529 case SECCLASS_UDP_SOCKET: 4530 netif_perm = NETIF__UDP_SEND; 4531 node_perm = NODE__UDP_SEND; 4532 send_perm = UDP_SOCKET__SEND_MSG; 4533 break; 4534 case SECCLASS_TCP_SOCKET: 4535 netif_perm = NETIF__TCP_SEND; 4536 node_perm = NODE__TCP_SEND; 4537 send_perm = TCP_SOCKET__SEND_MSG; 4538 break; 4539 case SECCLASS_DCCP_SOCKET: 4540 netif_perm = NETIF__DCCP_SEND; 4541 node_perm = NODE__DCCP_SEND; 4542 send_perm = DCCP_SOCKET__SEND_MSG; 4543 break; 4544 default: 4545 netif_perm = NETIF__RAWIP_SEND; 4546 node_perm = NODE__RAWIP_SEND; 4547 send_perm = 0; 4548 break; 4549 } 4550 4551 err = sel_netif_sid(ifindex, &if_sid); 4552 if (err) 4553 return err; 4554 err = avc_has_perm(sk_sid, if_sid, SECCLASS_NETIF, netif_perm, ad); 4555 return err; 4556 4557 err = sel_netnode_sid(addrp, family, &node_sid); 4558 if (err) 4559 return err; 4560 err = avc_has_perm(sk_sid, node_sid, SECCLASS_NODE, node_perm, ad); 4561 if (err) 4562 return err; 4563 4564 if (send_perm != 0) 4565 return 0; 4566 4567 err = sel_netport_sid(sk->sk_protocol, 4568 ntohs(ad->u.net.dport), &port_sid); 4569 if (unlikely(err)) { 4570 printk(KERN_WARNING 4571 "SELinux: failure in" 4572 " selinux_ip_postroute_iptables_compat()," 4573 " network port label not found\n"); 4574 return err; 4575 } 4576 return avc_has_perm(sk_sid, port_sid, sk_class, send_perm, ad); 4577 } 4578 4579 static unsigned int selinux_ip_postroute_compat(struct sk_buff *skb, 4580 int ifindex, 4581 u16 family) 4582 { 4583 struct sock *sk = skb->sk; 4584 struct sk_security_struct *sksec; 4585 struct avc_audit_data ad; 4586 char *addrp; 4587 u8 proto; 4588 4589 if (sk == NULL) 4590 return NF_ACCEPT; 4591 sksec = sk->sk_security; 4592 4593 AVC_AUDIT_DATA_INIT(&ad, NET); 4594 ad.u.net.netif = ifindex; 4595 ad.u.net.family = family; 4596 if (selinux_parse_skb(skb, &ad, &addrp, 0, &proto)) 4597 return NF_DROP; 4598 4599 if (selinux_compat_net) { 4600 if (selinux_ip_postroute_iptables_compat(skb->sk, ifindex, 4601 &ad, family, addrp)) 4602 return NF_DROP; 4603 } else { 4604 if (avc_has_perm(sksec->sid, skb->secmark, 4605 SECCLASS_PACKET, PACKET__SEND, &ad)) 4606 return NF_DROP; 4607 } 4608 4609 if (selinux_policycap_netpeer) 4610 if (selinux_xfrm_postroute_last(sksec->sid, skb, &ad, proto)) 4611 return NF_DROP; 4612 4613 return NF_ACCEPT; 4614 } 4615 4616 static unsigned int selinux_ip_postroute(struct sk_buff *skb, int ifindex, 4617 u16 family) 4618 { 4619 u32 secmark_perm; 4620 u32 peer_sid; 4621 struct sock *sk; 4622 struct avc_audit_data ad; 4623 char *addrp; 4624 u8 secmark_active; 4625 u8 peerlbl_active; 4626 4627 /* If any sort of compatibility mode is enabled then handoff processing 4628 * to the selinux_ip_postroute_compat() function to deal with the 4629 * special handling. We do this in an attempt to keep this function 4630 * as fast and as clean as possible. */ 4631 if (selinux_compat_net || !selinux_policycap_netpeer) 4632 return selinux_ip_postroute_compat(skb, ifindex, family); 4633 4634 /* If skb->dst->xfrm is non-NULL then the packet is undergoing an IPsec 4635 * packet transformation so allow the packet to pass without any checks 4636 * since we'll have another chance to perform access control checks 4637 * when the packet is on it's final way out. 4638 * NOTE: there appear to be some IPv6 multicast cases where skb->dst 4639 * is NULL, in this case go ahead and apply access control. */ 4640 if (skb->dst != NULL && skb->dst->xfrm != NULL) 4641 return NF_ACCEPT; 4642 4643 secmark_active = selinux_secmark_enabled(); 4644 peerlbl_active = netlbl_enabled() || selinux_xfrm_enabled(); 4645 if (!secmark_active && !peerlbl_active) 4646 return NF_ACCEPT; 4647 4648 /* if the packet is being forwarded then get the peer label from the 4649 * packet itself; otherwise check to see if it is from a local 4650 * application or the kernel, if from an application get the peer label 4651 * from the sending socket, otherwise use the kernel's sid */ 4652 sk = skb->sk; 4653 if (sk == NULL) { 4654 switch (family) { 4655 case PF_INET: 4656 if (IPCB(skb)->flags & IPSKB_FORWARDED) 4657 secmark_perm = PACKET__FORWARD_OUT; 4658 else 4659 secmark_perm = PACKET__SEND; 4660 break; 4661 case PF_INET6: 4662 if (IP6CB(skb)->flags & IP6SKB_FORWARDED) 4663 secmark_perm = PACKET__FORWARD_OUT; 4664 else 4665 secmark_perm = PACKET__SEND; 4666 break; 4667 default: 4668 return NF_DROP; 4669 } 4670 if (secmark_perm == PACKET__FORWARD_OUT) { 4671 if (selinux_skb_peerlbl_sid(skb, family, &peer_sid)) 4672 return NF_DROP; 4673 } else 4674 peer_sid = SECINITSID_KERNEL; 4675 } else { 4676 struct sk_security_struct *sksec = sk->sk_security; 4677 peer_sid = sksec->sid; 4678 secmark_perm = PACKET__SEND; 4679 } 4680 4681 AVC_AUDIT_DATA_INIT(&ad, NET); 4682 ad.u.net.netif = ifindex; 4683 ad.u.net.family = family; 4684 if (selinux_parse_skb(skb, &ad, &addrp, 0, NULL)) 4685 return NF_DROP; 4686 4687 if (secmark_active) 4688 if (avc_has_perm(peer_sid, skb->secmark, 4689 SECCLASS_PACKET, secmark_perm, &ad)) 4690 return NF_DROP; 4691 4692 if (peerlbl_active) { 4693 u32 if_sid; 4694 u32 node_sid; 4695 4696 if (sel_netif_sid(ifindex, &if_sid)) 4697 return NF_DROP; 4698 if (avc_has_perm(peer_sid, if_sid, 4699 SECCLASS_NETIF, NETIF__EGRESS, &ad)) 4700 return NF_DROP; 4701 4702 if (sel_netnode_sid(addrp, family, &node_sid)) 4703 return NF_DROP; 4704 if (avc_has_perm(peer_sid, node_sid, 4705 SECCLASS_NODE, NODE__SENDTO, &ad)) 4706 return NF_DROP; 4707 } 4708 4709 return NF_ACCEPT; 4710 } 4711 4712 static unsigned int selinux_ipv4_postroute(unsigned int hooknum, 4713 struct sk_buff *skb, 4714 const struct net_device *in, 4715 const struct net_device *out, 4716 int (*okfn)(struct sk_buff *)) 4717 { 4718 return selinux_ip_postroute(skb, out->ifindex, PF_INET); 4719 } 4720 4721 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE) 4722 static unsigned int selinux_ipv6_postroute(unsigned int hooknum, 4723 struct sk_buff *skb, 4724 const struct net_device *in, 4725 const struct net_device *out, 4726 int (*okfn)(struct sk_buff *)) 4727 { 4728 return selinux_ip_postroute(skb, out->ifindex, PF_INET6); 4729 } 4730 #endif /* IPV6 */ 4731 4732 #endif /* CONFIG_NETFILTER */ 4733 4734 static int selinux_netlink_send(struct sock *sk, struct sk_buff *skb) 4735 { 4736 int err; 4737 4738 err = secondary_ops->netlink_send(sk, skb); 4739 if (err) 4740 return err; 4741 4742 if (policydb_loaded_version >= POLICYDB_VERSION_NLCLASS) 4743 err = selinux_nlmsg_perm(sk, skb); 4744 4745 return err; 4746 } 4747 4748 static int selinux_netlink_recv(struct sk_buff *skb, int capability) 4749 { 4750 int err; 4751 struct avc_audit_data ad; 4752 4753 err = secondary_ops->netlink_recv(skb, capability); 4754 if (err) 4755 return err; 4756 4757 AVC_AUDIT_DATA_INIT(&ad, CAP); 4758 ad.u.cap = capability; 4759 4760 return avc_has_perm(NETLINK_CB(skb).sid, NETLINK_CB(skb).sid, 4761 SECCLASS_CAPABILITY, CAP_TO_MASK(capability), &ad); 4762 } 4763 4764 static int ipc_alloc_security(struct task_struct *task, 4765 struct kern_ipc_perm *perm, 4766 u16 sclass) 4767 { 4768 struct task_security_struct *tsec = task->cred->security; 4769 struct ipc_security_struct *isec; 4770 4771 isec = kzalloc(sizeof(struct ipc_security_struct), GFP_KERNEL); 4772 if (!isec) 4773 return -ENOMEM; 4774 4775 isec->sclass = sclass; 4776 isec->sid = tsec->sid; 4777 perm->security = isec; 4778 4779 return 0; 4780 } 4781 4782 static void ipc_free_security(struct kern_ipc_perm *perm) 4783 { 4784 struct ipc_security_struct *isec = perm->security; 4785 perm->security = NULL; 4786 kfree(isec); 4787 } 4788 4789 static int msg_msg_alloc_security(struct msg_msg *msg) 4790 { 4791 struct msg_security_struct *msec; 4792 4793 msec = kzalloc(sizeof(struct msg_security_struct), GFP_KERNEL); 4794 if (!msec) 4795 return -ENOMEM; 4796 4797 msec->sid = SECINITSID_UNLABELED; 4798 msg->security = msec; 4799 4800 return 0; 4801 } 4802 4803 static void msg_msg_free_security(struct msg_msg *msg) 4804 { 4805 struct msg_security_struct *msec = msg->security; 4806 4807 msg->security = NULL; 4808 kfree(msec); 4809 } 4810 4811 static int ipc_has_perm(struct kern_ipc_perm *ipc_perms, 4812 u32 perms) 4813 { 4814 struct task_security_struct *tsec; 4815 struct ipc_security_struct *isec; 4816 struct avc_audit_data ad; 4817 4818 tsec = current->cred->security; 4819 isec = ipc_perms->security; 4820 4821 AVC_AUDIT_DATA_INIT(&ad, IPC); 4822 ad.u.ipc_id = ipc_perms->key; 4823 4824 return avc_has_perm(tsec->sid, isec->sid, isec->sclass, perms, &ad); 4825 } 4826 4827 static int selinux_msg_msg_alloc_security(struct msg_msg *msg) 4828 { 4829 return msg_msg_alloc_security(msg); 4830 } 4831 4832 static void selinux_msg_msg_free_security(struct msg_msg *msg) 4833 { 4834 msg_msg_free_security(msg); 4835 } 4836 4837 /* message queue security operations */ 4838 static int selinux_msg_queue_alloc_security(struct msg_queue *msq) 4839 { 4840 struct task_security_struct *tsec; 4841 struct ipc_security_struct *isec; 4842 struct avc_audit_data ad; 4843 int rc; 4844 4845 rc = ipc_alloc_security(current, &msq->q_perm, SECCLASS_MSGQ); 4846 if (rc) 4847 return rc; 4848 4849 tsec = current->cred->security; 4850 isec = msq->q_perm.security; 4851 4852 AVC_AUDIT_DATA_INIT(&ad, IPC); 4853 ad.u.ipc_id = msq->q_perm.key; 4854 4855 rc = avc_has_perm(tsec->sid, isec->sid, SECCLASS_MSGQ, 4856 MSGQ__CREATE, &ad); 4857 if (rc) { 4858 ipc_free_security(&msq->q_perm); 4859 return rc; 4860 } 4861 return 0; 4862 } 4863 4864 static void selinux_msg_queue_free_security(struct msg_queue *msq) 4865 { 4866 ipc_free_security(&msq->q_perm); 4867 } 4868 4869 static int selinux_msg_queue_associate(struct msg_queue *msq, int msqflg) 4870 { 4871 struct task_security_struct *tsec; 4872 struct ipc_security_struct *isec; 4873 struct avc_audit_data ad; 4874 4875 tsec = current->cred->security; 4876 isec = msq->q_perm.security; 4877 4878 AVC_AUDIT_DATA_INIT(&ad, IPC); 4879 ad.u.ipc_id = msq->q_perm.key; 4880 4881 return avc_has_perm(tsec->sid, isec->sid, SECCLASS_MSGQ, 4882 MSGQ__ASSOCIATE, &ad); 4883 } 4884 4885 static int selinux_msg_queue_msgctl(struct msg_queue *msq, int cmd) 4886 { 4887 int err; 4888 int perms; 4889 4890 switch (cmd) { 4891 case IPC_INFO: 4892 case MSG_INFO: 4893 /* No specific object, just general system-wide information. */ 4894 return task_has_system(current, SYSTEM__IPC_INFO); 4895 case IPC_STAT: 4896 case MSG_STAT: 4897 perms = MSGQ__GETATTR | MSGQ__ASSOCIATE; 4898 break; 4899 case IPC_SET: 4900 perms = MSGQ__SETATTR; 4901 break; 4902 case IPC_RMID: 4903 perms = MSGQ__DESTROY; 4904 break; 4905 default: 4906 return 0; 4907 } 4908 4909 err = ipc_has_perm(&msq->q_perm, perms); 4910 return err; 4911 } 4912 4913 static int selinux_msg_queue_msgsnd(struct msg_queue *msq, struct msg_msg *msg, int msqflg) 4914 { 4915 struct task_security_struct *tsec; 4916 struct ipc_security_struct *isec; 4917 struct msg_security_struct *msec; 4918 struct avc_audit_data ad; 4919 int rc; 4920 4921 tsec = current->cred->security; 4922 isec = msq->q_perm.security; 4923 msec = msg->security; 4924 4925 /* 4926 * First time through, need to assign label to the message 4927 */ 4928 if (msec->sid == SECINITSID_UNLABELED) { 4929 /* 4930 * Compute new sid based on current process and 4931 * message queue this message will be stored in 4932 */ 4933 rc = security_transition_sid(tsec->sid, 4934 isec->sid, 4935 SECCLASS_MSG, 4936 &msec->sid); 4937 if (rc) 4938 return rc; 4939 } 4940 4941 AVC_AUDIT_DATA_INIT(&ad, IPC); 4942 ad.u.ipc_id = msq->q_perm.key; 4943 4944 /* Can this process write to the queue? */ 4945 rc = avc_has_perm(tsec->sid, isec->sid, SECCLASS_MSGQ, 4946 MSGQ__WRITE, &ad); 4947 if (!rc) 4948 /* Can this process send the message */ 4949 rc = avc_has_perm(tsec->sid, msec->sid, 4950 SECCLASS_MSG, MSG__SEND, &ad); 4951 if (!rc) 4952 /* Can the message be put in the queue? */ 4953 rc = avc_has_perm(msec->sid, isec->sid, 4954 SECCLASS_MSGQ, MSGQ__ENQUEUE, &ad); 4955 4956 return rc; 4957 } 4958 4959 static int selinux_msg_queue_msgrcv(struct msg_queue *msq, struct msg_msg *msg, 4960 struct task_struct *target, 4961 long type, int mode) 4962 { 4963 struct task_security_struct *tsec; 4964 struct ipc_security_struct *isec; 4965 struct msg_security_struct *msec; 4966 struct avc_audit_data ad; 4967 int rc; 4968 4969 tsec = target->cred->security; 4970 isec = msq->q_perm.security; 4971 msec = msg->security; 4972 4973 AVC_AUDIT_DATA_INIT(&ad, IPC); 4974 ad.u.ipc_id = msq->q_perm.key; 4975 4976 rc = avc_has_perm(tsec->sid, isec->sid, 4977 SECCLASS_MSGQ, MSGQ__READ, &ad); 4978 if (!rc) 4979 rc = avc_has_perm(tsec->sid, msec->sid, 4980 SECCLASS_MSG, MSG__RECEIVE, &ad); 4981 return rc; 4982 } 4983 4984 /* Shared Memory security operations */ 4985 static int selinux_shm_alloc_security(struct shmid_kernel *shp) 4986 { 4987 struct task_security_struct *tsec; 4988 struct ipc_security_struct *isec; 4989 struct avc_audit_data ad; 4990 int rc; 4991 4992 rc = ipc_alloc_security(current, &shp->shm_perm, SECCLASS_SHM); 4993 if (rc) 4994 return rc; 4995 4996 tsec = current->cred->security; 4997 isec = shp->shm_perm.security; 4998 4999 AVC_AUDIT_DATA_INIT(&ad, IPC); 5000 ad.u.ipc_id = shp->shm_perm.key; 5001 5002 rc = avc_has_perm(tsec->sid, isec->sid, SECCLASS_SHM, 5003 SHM__CREATE, &ad); 5004 if (rc) { 5005 ipc_free_security(&shp->shm_perm); 5006 return rc; 5007 } 5008 return 0; 5009 } 5010 5011 static void selinux_shm_free_security(struct shmid_kernel *shp) 5012 { 5013 ipc_free_security(&shp->shm_perm); 5014 } 5015 5016 static int selinux_shm_associate(struct shmid_kernel *shp, int shmflg) 5017 { 5018 struct task_security_struct *tsec; 5019 struct ipc_security_struct *isec; 5020 struct avc_audit_data ad; 5021 5022 tsec = current->cred->security; 5023 isec = shp->shm_perm.security; 5024 5025 AVC_AUDIT_DATA_INIT(&ad, IPC); 5026 ad.u.ipc_id = shp->shm_perm.key; 5027 5028 return avc_has_perm(tsec->sid, isec->sid, SECCLASS_SHM, 5029 SHM__ASSOCIATE, &ad); 5030 } 5031 5032 /* Note, at this point, shp is locked down */ 5033 static int selinux_shm_shmctl(struct shmid_kernel *shp, int cmd) 5034 { 5035 int perms; 5036 int err; 5037 5038 switch (cmd) { 5039 case IPC_INFO: 5040 case SHM_INFO: 5041 /* No specific object, just general system-wide information. */ 5042 return task_has_system(current, SYSTEM__IPC_INFO); 5043 case IPC_STAT: 5044 case SHM_STAT: 5045 perms = SHM__GETATTR | SHM__ASSOCIATE; 5046 break; 5047 case IPC_SET: 5048 perms = SHM__SETATTR; 5049 break; 5050 case SHM_LOCK: 5051 case SHM_UNLOCK: 5052 perms = SHM__LOCK; 5053 break; 5054 case IPC_RMID: 5055 perms = SHM__DESTROY; 5056 break; 5057 default: 5058 return 0; 5059 } 5060 5061 err = ipc_has_perm(&shp->shm_perm, perms); 5062 return err; 5063 } 5064 5065 static int selinux_shm_shmat(struct shmid_kernel *shp, 5066 char __user *shmaddr, int shmflg) 5067 { 5068 u32 perms; 5069 int rc; 5070 5071 rc = secondary_ops->shm_shmat(shp, shmaddr, shmflg); 5072 if (rc) 5073 return rc; 5074 5075 if (shmflg & SHM_RDONLY) 5076 perms = SHM__READ; 5077 else 5078 perms = SHM__READ | SHM__WRITE; 5079 5080 return ipc_has_perm(&shp->shm_perm, perms); 5081 } 5082 5083 /* Semaphore security operations */ 5084 static int selinux_sem_alloc_security(struct sem_array *sma) 5085 { 5086 struct task_security_struct *tsec; 5087 struct ipc_security_struct *isec; 5088 struct avc_audit_data ad; 5089 int rc; 5090 5091 rc = ipc_alloc_security(current, &sma->sem_perm, SECCLASS_SEM); 5092 if (rc) 5093 return rc; 5094 5095 tsec = current->cred->security; 5096 isec = sma->sem_perm.security; 5097 5098 AVC_AUDIT_DATA_INIT(&ad, IPC); 5099 ad.u.ipc_id = sma->sem_perm.key; 5100 5101 rc = avc_has_perm(tsec->sid, isec->sid, SECCLASS_SEM, 5102 SEM__CREATE, &ad); 5103 if (rc) { 5104 ipc_free_security(&sma->sem_perm); 5105 return rc; 5106 } 5107 return 0; 5108 } 5109 5110 static void selinux_sem_free_security(struct sem_array *sma) 5111 { 5112 ipc_free_security(&sma->sem_perm); 5113 } 5114 5115 static int selinux_sem_associate(struct sem_array *sma, int semflg) 5116 { 5117 struct task_security_struct *tsec; 5118 struct ipc_security_struct *isec; 5119 struct avc_audit_data ad; 5120 5121 tsec = current->cred->security; 5122 isec = sma->sem_perm.security; 5123 5124 AVC_AUDIT_DATA_INIT(&ad, IPC); 5125 ad.u.ipc_id = sma->sem_perm.key; 5126 5127 return avc_has_perm(tsec->sid, isec->sid, SECCLASS_SEM, 5128 SEM__ASSOCIATE, &ad); 5129 } 5130 5131 /* Note, at this point, sma is locked down */ 5132 static int selinux_sem_semctl(struct sem_array *sma, int cmd) 5133 { 5134 int err; 5135 u32 perms; 5136 5137 switch (cmd) { 5138 case IPC_INFO: 5139 case SEM_INFO: 5140 /* No specific object, just general system-wide information. */ 5141 return task_has_system(current, SYSTEM__IPC_INFO); 5142 case GETPID: 5143 case GETNCNT: 5144 case GETZCNT: 5145 perms = SEM__GETATTR; 5146 break; 5147 case GETVAL: 5148 case GETALL: 5149 perms = SEM__READ; 5150 break; 5151 case SETVAL: 5152 case SETALL: 5153 perms = SEM__WRITE; 5154 break; 5155 case IPC_RMID: 5156 perms = SEM__DESTROY; 5157 break; 5158 case IPC_SET: 5159 perms = SEM__SETATTR; 5160 break; 5161 case IPC_STAT: 5162 case SEM_STAT: 5163 perms = SEM__GETATTR | SEM__ASSOCIATE; 5164 break; 5165 default: 5166 return 0; 5167 } 5168 5169 err = ipc_has_perm(&sma->sem_perm, perms); 5170 return err; 5171 } 5172 5173 static int selinux_sem_semop(struct sem_array *sma, 5174 struct sembuf *sops, unsigned nsops, int alter) 5175 { 5176 u32 perms; 5177 5178 if (alter) 5179 perms = SEM__READ | SEM__WRITE; 5180 else 5181 perms = SEM__READ; 5182 5183 return ipc_has_perm(&sma->sem_perm, perms); 5184 } 5185 5186 static int selinux_ipc_permission(struct kern_ipc_perm *ipcp, short flag) 5187 { 5188 u32 av = 0; 5189 5190 av = 0; 5191 if (flag & S_IRUGO) 5192 av |= IPC__UNIX_READ; 5193 if (flag & S_IWUGO) 5194 av |= IPC__UNIX_WRITE; 5195 5196 if (av == 0) 5197 return 0; 5198 5199 return ipc_has_perm(ipcp, av); 5200 } 5201 5202 static void selinux_ipc_getsecid(struct kern_ipc_perm *ipcp, u32 *secid) 5203 { 5204 struct ipc_security_struct *isec = ipcp->security; 5205 *secid = isec->sid; 5206 } 5207 5208 static void selinux_d_instantiate(struct dentry *dentry, struct inode *inode) 5209 { 5210 if (inode) 5211 inode_doinit_with_dentry(inode, dentry); 5212 } 5213 5214 static int selinux_getprocattr(struct task_struct *p, 5215 char *name, char **value) 5216 { 5217 struct task_security_struct *tsec; 5218 u32 sid; 5219 int error; 5220 unsigned len; 5221 5222 if (current != p) { 5223 error = task_has_perm(current, p, PROCESS__GETATTR); 5224 if (error) 5225 return error; 5226 } 5227 5228 tsec = p->cred->security; 5229 5230 if (!strcmp(name, "current")) 5231 sid = tsec->sid; 5232 else if (!strcmp(name, "prev")) 5233 sid = tsec->osid; 5234 else if (!strcmp(name, "exec")) 5235 sid = tsec->exec_sid; 5236 else if (!strcmp(name, "fscreate")) 5237 sid = tsec->create_sid; 5238 else if (!strcmp(name, "keycreate")) 5239 sid = tsec->keycreate_sid; 5240 else if (!strcmp(name, "sockcreate")) 5241 sid = tsec->sockcreate_sid; 5242 else 5243 return -EINVAL; 5244 5245 if (!sid) 5246 return 0; 5247 5248 error = security_sid_to_context(sid, value, &len); 5249 if (error) 5250 return error; 5251 return len; 5252 } 5253 5254 static int selinux_setprocattr(struct task_struct *p, 5255 char *name, void *value, size_t size) 5256 { 5257 struct task_security_struct *tsec; 5258 struct task_struct *tracer; 5259 u32 sid = 0; 5260 int error; 5261 char *str = value; 5262 5263 if (current != p) { 5264 /* SELinux only allows a process to change its own 5265 security attributes. */ 5266 return -EACCES; 5267 } 5268 5269 /* 5270 * Basic control over ability to set these attributes at all. 5271 * current == p, but we'll pass them separately in case the 5272 * above restriction is ever removed. 5273 */ 5274 if (!strcmp(name, "exec")) 5275 error = task_has_perm(current, p, PROCESS__SETEXEC); 5276 else if (!strcmp(name, "fscreate")) 5277 error = task_has_perm(current, p, PROCESS__SETFSCREATE); 5278 else if (!strcmp(name, "keycreate")) 5279 error = task_has_perm(current, p, PROCESS__SETKEYCREATE); 5280 else if (!strcmp(name, "sockcreate")) 5281 error = task_has_perm(current, p, PROCESS__SETSOCKCREATE); 5282 else if (!strcmp(name, "current")) 5283 error = task_has_perm(current, p, PROCESS__SETCURRENT); 5284 else 5285 error = -EINVAL; 5286 if (error) 5287 return error; 5288 5289 /* Obtain a SID for the context, if one was specified. */ 5290 if (size && str[1] && str[1] != '\n') { 5291 if (str[size-1] == '\n') { 5292 str[size-1] = 0; 5293 size--; 5294 } 5295 error = security_context_to_sid(value, size, &sid); 5296 if (error == -EINVAL && !strcmp(name, "fscreate")) { 5297 if (!capable(CAP_MAC_ADMIN)) 5298 return error; 5299 error = security_context_to_sid_force(value, size, 5300 &sid); 5301 } 5302 if (error) 5303 return error; 5304 } 5305 5306 /* Permission checking based on the specified context is 5307 performed during the actual operation (execve, 5308 open/mkdir/...), when we know the full context of the 5309 operation. See selinux_bprm_set_security for the execve 5310 checks and may_create for the file creation checks. The 5311 operation will then fail if the context is not permitted. */ 5312 tsec = p->cred->security; 5313 if (!strcmp(name, "exec")) 5314 tsec->exec_sid = sid; 5315 else if (!strcmp(name, "fscreate")) 5316 tsec->create_sid = sid; 5317 else if (!strcmp(name, "keycreate")) { 5318 error = may_create_key(sid, p); 5319 if (error) 5320 return error; 5321 tsec->keycreate_sid = sid; 5322 } else if (!strcmp(name, "sockcreate")) 5323 tsec->sockcreate_sid = sid; 5324 else if (!strcmp(name, "current")) { 5325 struct av_decision avd; 5326 5327 if (sid == 0) 5328 return -EINVAL; 5329 /* 5330 * SELinux allows to change context in the following case only. 5331 * - Single threaded processes. 5332 * - Multi threaded processes intend to change its context into 5333 * more restricted domain (defined by TYPEBOUNDS statement). 5334 */ 5335 if (atomic_read(&p->mm->mm_users) != 1) { 5336 struct task_struct *g, *t; 5337 struct mm_struct *mm = p->mm; 5338 read_lock(&tasklist_lock); 5339 do_each_thread(g, t) { 5340 if (t->mm == mm && t != p) { 5341 read_unlock(&tasklist_lock); 5342 error = security_bounded_transition(tsec->sid, sid); 5343 if (!error) 5344 goto boundary_ok; 5345 5346 return error; 5347 } 5348 } while_each_thread(g, t); 5349 read_unlock(&tasklist_lock); 5350 } 5351 boundary_ok: 5352 5353 /* Check permissions for the transition. */ 5354 error = avc_has_perm(tsec->sid, sid, SECCLASS_PROCESS, 5355 PROCESS__DYNTRANSITION, NULL); 5356 if (error) 5357 return error; 5358 5359 /* Check for ptracing, and update the task SID if ok. 5360 Otherwise, leave SID unchanged and fail. */ 5361 task_lock(p); 5362 rcu_read_lock(); 5363 tracer = tracehook_tracer_task(p); 5364 if (tracer != NULL) { 5365 struct task_security_struct *ptsec = 5366 tracer->cred->security; 5367 u32 ptsid = ptsec->sid; 5368 rcu_read_unlock(); 5369 error = avc_has_perm_noaudit(ptsid, sid, 5370 SECCLASS_PROCESS, 5371 PROCESS__PTRACE, 0, &avd); 5372 if (!error) 5373 tsec->sid = sid; 5374 task_unlock(p); 5375 avc_audit(ptsid, sid, SECCLASS_PROCESS, 5376 PROCESS__PTRACE, &avd, error, NULL); 5377 if (error) 5378 return error; 5379 } else { 5380 rcu_read_unlock(); 5381 tsec->sid = sid; 5382 task_unlock(p); 5383 } 5384 } else 5385 return -EINVAL; 5386 5387 return size; 5388 } 5389 5390 static int selinux_secid_to_secctx(u32 secid, char **secdata, u32 *seclen) 5391 { 5392 return security_sid_to_context(secid, secdata, seclen); 5393 } 5394 5395 static int selinux_secctx_to_secid(const char *secdata, u32 seclen, u32 *secid) 5396 { 5397 return security_context_to_sid(secdata, seclen, secid); 5398 } 5399 5400 static void selinux_release_secctx(char *secdata, u32 seclen) 5401 { 5402 kfree(secdata); 5403 } 5404 5405 #ifdef CONFIG_KEYS 5406 5407 static int selinux_key_alloc(struct key *k, struct task_struct *tsk, 5408 unsigned long flags) 5409 { 5410 struct task_security_struct *tsec = tsk->cred->security; 5411 struct key_security_struct *ksec; 5412 5413 ksec = kzalloc(sizeof(struct key_security_struct), GFP_KERNEL); 5414 if (!ksec) 5415 return -ENOMEM; 5416 5417 if (tsec->keycreate_sid) 5418 ksec->sid = tsec->keycreate_sid; 5419 else 5420 ksec->sid = tsec->sid; 5421 k->security = ksec; 5422 5423 return 0; 5424 } 5425 5426 static void selinux_key_free(struct key *k) 5427 { 5428 struct key_security_struct *ksec = k->security; 5429 5430 k->security = NULL; 5431 kfree(ksec); 5432 } 5433 5434 static int selinux_key_permission(key_ref_t key_ref, 5435 struct task_struct *ctx, 5436 key_perm_t perm) 5437 { 5438 struct key *key; 5439 struct task_security_struct *tsec; 5440 struct key_security_struct *ksec; 5441 5442 key = key_ref_to_ptr(key_ref); 5443 5444 tsec = ctx->cred->security; 5445 ksec = key->security; 5446 5447 /* if no specific permissions are requested, we skip the 5448 permission check. No serious, additional covert channels 5449 appear to be created. */ 5450 if (perm == 0) 5451 return 0; 5452 5453 return avc_has_perm(tsec->sid, ksec->sid, 5454 SECCLASS_KEY, perm, NULL); 5455 } 5456 5457 static int selinux_key_getsecurity(struct key *key, char **_buffer) 5458 { 5459 struct key_security_struct *ksec = key->security; 5460 char *context = NULL; 5461 unsigned len; 5462 int rc; 5463 5464 rc = security_sid_to_context(ksec->sid, &context, &len); 5465 if (!rc) 5466 rc = len; 5467 *_buffer = context; 5468 return rc; 5469 } 5470 5471 #endif 5472 5473 static struct security_operations selinux_ops = { 5474 .name = "selinux", 5475 5476 .ptrace_may_access = selinux_ptrace_may_access, 5477 .ptrace_traceme = selinux_ptrace_traceme, 5478 .capget = selinux_capget, 5479 .capset_check = selinux_capset_check, 5480 .capset_set = selinux_capset_set, 5481 .sysctl = selinux_sysctl, 5482 .capable = selinux_capable, 5483 .quotactl = selinux_quotactl, 5484 .quota_on = selinux_quota_on, 5485 .syslog = selinux_syslog, 5486 .vm_enough_memory = selinux_vm_enough_memory, 5487 5488 .netlink_send = selinux_netlink_send, 5489 .netlink_recv = selinux_netlink_recv, 5490 5491 .bprm_alloc_security = selinux_bprm_alloc_security, 5492 .bprm_free_security = selinux_bprm_free_security, 5493 .bprm_apply_creds = selinux_bprm_apply_creds, 5494 .bprm_post_apply_creds = selinux_bprm_post_apply_creds, 5495 .bprm_set_security = selinux_bprm_set_security, 5496 .bprm_check_security = selinux_bprm_check_security, 5497 .bprm_secureexec = selinux_bprm_secureexec, 5498 5499 .sb_alloc_security = selinux_sb_alloc_security, 5500 .sb_free_security = selinux_sb_free_security, 5501 .sb_copy_data = selinux_sb_copy_data, 5502 .sb_kern_mount = selinux_sb_kern_mount, 5503 .sb_show_options = selinux_sb_show_options, 5504 .sb_statfs = selinux_sb_statfs, 5505 .sb_mount = selinux_mount, 5506 .sb_umount = selinux_umount, 5507 .sb_set_mnt_opts = selinux_set_mnt_opts, 5508 .sb_clone_mnt_opts = selinux_sb_clone_mnt_opts, 5509 .sb_parse_opts_str = selinux_parse_opts_str, 5510 5511 5512 .inode_alloc_security = selinux_inode_alloc_security, 5513 .inode_free_security = selinux_inode_free_security, 5514 .inode_init_security = selinux_inode_init_security, 5515 .inode_create = selinux_inode_create, 5516 .inode_link = selinux_inode_link, 5517 .inode_unlink = selinux_inode_unlink, 5518 .inode_symlink = selinux_inode_symlink, 5519 .inode_mkdir = selinux_inode_mkdir, 5520 .inode_rmdir = selinux_inode_rmdir, 5521 .inode_mknod = selinux_inode_mknod, 5522 .inode_rename = selinux_inode_rename, 5523 .inode_readlink = selinux_inode_readlink, 5524 .inode_follow_link = selinux_inode_follow_link, 5525 .inode_permission = selinux_inode_permission, 5526 .inode_setattr = selinux_inode_setattr, 5527 .inode_getattr = selinux_inode_getattr, 5528 .inode_setxattr = selinux_inode_setxattr, 5529 .inode_post_setxattr = selinux_inode_post_setxattr, 5530 .inode_getxattr = selinux_inode_getxattr, 5531 .inode_listxattr = selinux_inode_listxattr, 5532 .inode_removexattr = selinux_inode_removexattr, 5533 .inode_getsecurity = selinux_inode_getsecurity, 5534 .inode_setsecurity = selinux_inode_setsecurity, 5535 .inode_listsecurity = selinux_inode_listsecurity, 5536 .inode_need_killpriv = selinux_inode_need_killpriv, 5537 .inode_killpriv = selinux_inode_killpriv, 5538 .inode_getsecid = selinux_inode_getsecid, 5539 5540 .file_permission = selinux_file_permission, 5541 .file_alloc_security = selinux_file_alloc_security, 5542 .file_free_security = selinux_file_free_security, 5543 .file_ioctl = selinux_file_ioctl, 5544 .file_mmap = selinux_file_mmap, 5545 .file_mprotect = selinux_file_mprotect, 5546 .file_lock = selinux_file_lock, 5547 .file_fcntl = selinux_file_fcntl, 5548 .file_set_fowner = selinux_file_set_fowner, 5549 .file_send_sigiotask = selinux_file_send_sigiotask, 5550 .file_receive = selinux_file_receive, 5551 5552 .dentry_open = selinux_dentry_open, 5553 5554 .task_create = selinux_task_create, 5555 .task_alloc_security = selinux_task_alloc_security, 5556 .task_free_security = selinux_task_free_security, 5557 .task_setuid = selinux_task_setuid, 5558 .task_post_setuid = selinux_task_post_setuid, 5559 .task_setgid = selinux_task_setgid, 5560 .task_setpgid = selinux_task_setpgid, 5561 .task_getpgid = selinux_task_getpgid, 5562 .task_getsid = selinux_task_getsid, 5563 .task_getsecid = selinux_task_getsecid, 5564 .task_setgroups = selinux_task_setgroups, 5565 .task_setnice = selinux_task_setnice, 5566 .task_setioprio = selinux_task_setioprio, 5567 .task_getioprio = selinux_task_getioprio, 5568 .task_setrlimit = selinux_task_setrlimit, 5569 .task_setscheduler = selinux_task_setscheduler, 5570 .task_getscheduler = selinux_task_getscheduler, 5571 .task_movememory = selinux_task_movememory, 5572 .task_kill = selinux_task_kill, 5573 .task_wait = selinux_task_wait, 5574 .task_prctl = selinux_task_prctl, 5575 .task_reparent_to_init = selinux_task_reparent_to_init, 5576 .task_to_inode = selinux_task_to_inode, 5577 5578 .ipc_permission = selinux_ipc_permission, 5579 .ipc_getsecid = selinux_ipc_getsecid, 5580 5581 .msg_msg_alloc_security = selinux_msg_msg_alloc_security, 5582 .msg_msg_free_security = selinux_msg_msg_free_security, 5583 5584 .msg_queue_alloc_security = selinux_msg_queue_alloc_security, 5585 .msg_queue_free_security = selinux_msg_queue_free_security, 5586 .msg_queue_associate = selinux_msg_queue_associate, 5587 .msg_queue_msgctl = selinux_msg_queue_msgctl, 5588 .msg_queue_msgsnd = selinux_msg_queue_msgsnd, 5589 .msg_queue_msgrcv = selinux_msg_queue_msgrcv, 5590 5591 .shm_alloc_security = selinux_shm_alloc_security, 5592 .shm_free_security = selinux_shm_free_security, 5593 .shm_associate = selinux_shm_associate, 5594 .shm_shmctl = selinux_shm_shmctl, 5595 .shm_shmat = selinux_shm_shmat, 5596 5597 .sem_alloc_security = selinux_sem_alloc_security, 5598 .sem_free_security = selinux_sem_free_security, 5599 .sem_associate = selinux_sem_associate, 5600 .sem_semctl = selinux_sem_semctl, 5601 .sem_semop = selinux_sem_semop, 5602 5603 .d_instantiate = selinux_d_instantiate, 5604 5605 .getprocattr = selinux_getprocattr, 5606 .setprocattr = selinux_setprocattr, 5607 5608 .secid_to_secctx = selinux_secid_to_secctx, 5609 .secctx_to_secid = selinux_secctx_to_secid, 5610 .release_secctx = selinux_release_secctx, 5611 5612 .unix_stream_connect = selinux_socket_unix_stream_connect, 5613 .unix_may_send = selinux_socket_unix_may_send, 5614 5615 .socket_create = selinux_socket_create, 5616 .socket_post_create = selinux_socket_post_create, 5617 .socket_bind = selinux_socket_bind, 5618 .socket_connect = selinux_socket_connect, 5619 .socket_listen = selinux_socket_listen, 5620 .socket_accept = selinux_socket_accept, 5621 .socket_sendmsg = selinux_socket_sendmsg, 5622 .socket_recvmsg = selinux_socket_recvmsg, 5623 .socket_getsockname = selinux_socket_getsockname, 5624 .socket_getpeername = selinux_socket_getpeername, 5625 .socket_getsockopt = selinux_socket_getsockopt, 5626 .socket_setsockopt = selinux_socket_setsockopt, 5627 .socket_shutdown = selinux_socket_shutdown, 5628 .socket_sock_rcv_skb = selinux_socket_sock_rcv_skb, 5629 .socket_getpeersec_stream = selinux_socket_getpeersec_stream, 5630 .socket_getpeersec_dgram = selinux_socket_getpeersec_dgram, 5631 .sk_alloc_security = selinux_sk_alloc_security, 5632 .sk_free_security = selinux_sk_free_security, 5633 .sk_clone_security = selinux_sk_clone_security, 5634 .sk_getsecid = selinux_sk_getsecid, 5635 .sock_graft = selinux_sock_graft, 5636 .inet_conn_request = selinux_inet_conn_request, 5637 .inet_csk_clone = selinux_inet_csk_clone, 5638 .inet_conn_established = selinux_inet_conn_established, 5639 .req_classify_flow = selinux_req_classify_flow, 5640 5641 #ifdef CONFIG_SECURITY_NETWORK_XFRM 5642 .xfrm_policy_alloc_security = selinux_xfrm_policy_alloc, 5643 .xfrm_policy_clone_security = selinux_xfrm_policy_clone, 5644 .xfrm_policy_free_security = selinux_xfrm_policy_free, 5645 .xfrm_policy_delete_security = selinux_xfrm_policy_delete, 5646 .xfrm_state_alloc_security = selinux_xfrm_state_alloc, 5647 .xfrm_state_free_security = selinux_xfrm_state_free, 5648 .xfrm_state_delete_security = selinux_xfrm_state_delete, 5649 .xfrm_policy_lookup = selinux_xfrm_policy_lookup, 5650 .xfrm_state_pol_flow_match = selinux_xfrm_state_pol_flow_match, 5651 .xfrm_decode_session = selinux_xfrm_decode_session, 5652 #endif 5653 5654 #ifdef CONFIG_KEYS 5655 .key_alloc = selinux_key_alloc, 5656 .key_free = selinux_key_free, 5657 .key_permission = selinux_key_permission, 5658 .key_getsecurity = selinux_key_getsecurity, 5659 #endif 5660 5661 #ifdef CONFIG_AUDIT 5662 .audit_rule_init = selinux_audit_rule_init, 5663 .audit_rule_known = selinux_audit_rule_known, 5664 .audit_rule_match = selinux_audit_rule_match, 5665 .audit_rule_free = selinux_audit_rule_free, 5666 #endif 5667 }; 5668 5669 static __init int selinux_init(void) 5670 { 5671 struct task_security_struct *tsec; 5672 5673 if (!security_module_enable(&selinux_ops)) { 5674 selinux_enabled = 0; 5675 return 0; 5676 } 5677 5678 if (!selinux_enabled) { 5679 printk(KERN_INFO "SELinux: Disabled at boot.\n"); 5680 return 0; 5681 } 5682 5683 printk(KERN_INFO "SELinux: Initializing.\n"); 5684 5685 /* Set the security state for the initial task. */ 5686 if (task_alloc_security(current)) 5687 panic("SELinux: Failed to initialize initial task.\n"); 5688 tsec = current->cred->security; 5689 tsec->osid = tsec->sid = SECINITSID_KERNEL; 5690 5691 sel_inode_cache = kmem_cache_create("selinux_inode_security", 5692 sizeof(struct inode_security_struct), 5693 0, SLAB_PANIC, NULL); 5694 avc_init(); 5695 5696 secondary_ops = security_ops; 5697 if (!secondary_ops) 5698 panic("SELinux: No initial security operations\n"); 5699 if (register_security(&selinux_ops)) 5700 panic("SELinux: Unable to register with kernel.\n"); 5701 5702 if (selinux_enforcing) 5703 printk(KERN_DEBUG "SELinux: Starting in enforcing mode\n"); 5704 else 5705 printk(KERN_DEBUG "SELinux: Starting in permissive mode\n"); 5706 5707 return 0; 5708 } 5709 5710 void selinux_complete_init(void) 5711 { 5712 printk(KERN_DEBUG "SELinux: Completing initialization.\n"); 5713 5714 /* Set up any superblocks initialized prior to the policy load. */ 5715 printk(KERN_DEBUG "SELinux: Setting up existing superblocks.\n"); 5716 spin_lock(&sb_lock); 5717 spin_lock(&sb_security_lock); 5718 next_sb: 5719 if (!list_empty(&superblock_security_head)) { 5720 struct superblock_security_struct *sbsec = 5721 list_entry(superblock_security_head.next, 5722 struct superblock_security_struct, 5723 list); 5724 struct super_block *sb = sbsec->sb; 5725 sb->s_count++; 5726 spin_unlock(&sb_security_lock); 5727 spin_unlock(&sb_lock); 5728 down_read(&sb->s_umount); 5729 if (sb->s_root) 5730 superblock_doinit(sb, NULL); 5731 drop_super(sb); 5732 spin_lock(&sb_lock); 5733 spin_lock(&sb_security_lock); 5734 list_del_init(&sbsec->list); 5735 goto next_sb; 5736 } 5737 spin_unlock(&sb_security_lock); 5738 spin_unlock(&sb_lock); 5739 } 5740 5741 /* SELinux requires early initialization in order to label 5742 all processes and objects when they are created. */ 5743 security_initcall(selinux_init); 5744 5745 #if defined(CONFIG_NETFILTER) 5746 5747 static struct nf_hook_ops selinux_ipv4_ops[] = { 5748 { 5749 .hook = selinux_ipv4_postroute, 5750 .owner = THIS_MODULE, 5751 .pf = PF_INET, 5752 .hooknum = NF_INET_POST_ROUTING, 5753 .priority = NF_IP_PRI_SELINUX_LAST, 5754 }, 5755 { 5756 .hook = selinux_ipv4_forward, 5757 .owner = THIS_MODULE, 5758 .pf = PF_INET, 5759 .hooknum = NF_INET_FORWARD, 5760 .priority = NF_IP_PRI_SELINUX_FIRST, 5761 }, 5762 { 5763 .hook = selinux_ipv4_output, 5764 .owner = THIS_MODULE, 5765 .pf = PF_INET, 5766 .hooknum = NF_INET_LOCAL_OUT, 5767 .priority = NF_IP_PRI_SELINUX_FIRST, 5768 } 5769 }; 5770 5771 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE) 5772 5773 static struct nf_hook_ops selinux_ipv6_ops[] = { 5774 { 5775 .hook = selinux_ipv6_postroute, 5776 .owner = THIS_MODULE, 5777 .pf = PF_INET6, 5778 .hooknum = NF_INET_POST_ROUTING, 5779 .priority = NF_IP6_PRI_SELINUX_LAST, 5780 }, 5781 { 5782 .hook = selinux_ipv6_forward, 5783 .owner = THIS_MODULE, 5784 .pf = PF_INET6, 5785 .hooknum = NF_INET_FORWARD, 5786 .priority = NF_IP6_PRI_SELINUX_FIRST, 5787 } 5788 }; 5789 5790 #endif /* IPV6 */ 5791 5792 static int __init selinux_nf_ip_init(void) 5793 { 5794 int err = 0; 5795 5796 if (!selinux_enabled) 5797 goto out; 5798 5799 printk(KERN_DEBUG "SELinux: Registering netfilter hooks\n"); 5800 5801 err = nf_register_hooks(selinux_ipv4_ops, ARRAY_SIZE(selinux_ipv4_ops)); 5802 if (err) 5803 panic("SELinux: nf_register_hooks for IPv4: error %d\n", err); 5804 5805 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE) 5806 err = nf_register_hooks(selinux_ipv6_ops, ARRAY_SIZE(selinux_ipv6_ops)); 5807 if (err) 5808 panic("SELinux: nf_register_hooks for IPv6: error %d\n", err); 5809 #endif /* IPV6 */ 5810 5811 out: 5812 return err; 5813 } 5814 5815 __initcall(selinux_nf_ip_init); 5816 5817 #ifdef CONFIG_SECURITY_SELINUX_DISABLE 5818 static void selinux_nf_ip_exit(void) 5819 { 5820 printk(KERN_DEBUG "SELinux: Unregistering netfilter hooks\n"); 5821 5822 nf_unregister_hooks(selinux_ipv4_ops, ARRAY_SIZE(selinux_ipv4_ops)); 5823 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE) 5824 nf_unregister_hooks(selinux_ipv6_ops, ARRAY_SIZE(selinux_ipv6_ops)); 5825 #endif /* IPV6 */ 5826 } 5827 #endif 5828 5829 #else /* CONFIG_NETFILTER */ 5830 5831 #ifdef CONFIG_SECURITY_SELINUX_DISABLE 5832 #define selinux_nf_ip_exit() 5833 #endif 5834 5835 #endif /* CONFIG_NETFILTER */ 5836 5837 #ifdef CONFIG_SECURITY_SELINUX_DISABLE 5838 static int selinux_disabled; 5839 5840 int selinux_disable(void) 5841 { 5842 extern void exit_sel_fs(void); 5843 5844 if (ss_initialized) { 5845 /* Not permitted after initial policy load. */ 5846 return -EINVAL; 5847 } 5848 5849 if (selinux_disabled) { 5850 /* Only do this once. */ 5851 return -EINVAL; 5852 } 5853 5854 printk(KERN_INFO "SELinux: Disabled at runtime.\n"); 5855 5856 selinux_disabled = 1; 5857 selinux_enabled = 0; 5858 5859 /* Reset security_ops to the secondary module, dummy or capability. */ 5860 security_ops = secondary_ops; 5861 5862 /* Unregister netfilter hooks. */ 5863 selinux_nf_ip_exit(); 5864 5865 /* Unregister selinuxfs. */ 5866 exit_sel_fs(); 5867 5868 return 0; 5869 } 5870 #endif 5871