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 Red Hat, Inc., James Morris <jmorris@redhat.com> 13 * Copyright (C) 2004-2005 Trusted Computer Solutions, Inc. 14 * <dgoeddel@trustedcs.com> 15 * Copyright (C) 2006 Hewlett-Packard Development Company, L.P. 16 * Paul Moore, <paul.moore@hp.com> 17 * 18 * This program is free software; you can redistribute it and/or modify 19 * it under the terms of the GNU General Public License version 2, 20 * as published by the Free Software Foundation. 21 */ 22 23 #include <linux/module.h> 24 #include <linux/init.h> 25 #include <linux/kernel.h> 26 #include <linux/ptrace.h> 27 #include <linux/errno.h> 28 #include <linux/sched.h> 29 #include <linux/security.h> 30 #include <linux/xattr.h> 31 #include <linux/capability.h> 32 #include <linux/unistd.h> 33 #include <linux/mm.h> 34 #include <linux/mman.h> 35 #include <linux/slab.h> 36 #include <linux/pagemap.h> 37 #include <linux/swap.h> 38 #include <linux/smp_lock.h> 39 #include <linux/spinlock.h> 40 #include <linux/syscalls.h> 41 #include <linux/file.h> 42 #include <linux/namei.h> 43 #include <linux/mount.h> 44 #include <linux/ext2_fs.h> 45 #include <linux/proc_fs.h> 46 #include <linux/kd.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 sysctl_local_port_range[] */ 52 #include <net/tcp.h> /* struct or_callable used in sock_rcv_skb */ 53 #include <asm/uaccess.h> 54 #include <asm/semaphore.h> 55 #include <asm/ioctls.h> 56 #include <linux/bitops.h> 57 #include <linux/interrupt.h> 58 #include <linux/netdevice.h> /* for network interface checks */ 59 #include <linux/netlink.h> 60 #include <linux/tcp.h> 61 #include <linux/udp.h> 62 #include <linux/quota.h> 63 #include <linux/un.h> /* for Unix socket types */ 64 #include <net/af_unix.h> /* for Unix socket types */ 65 #include <linux/parser.h> 66 #include <linux/nfs_mount.h> 67 #include <net/ipv6.h> 68 #include <linux/hugetlb.h> 69 #include <linux/personality.h> 70 #include <linux/sysctl.h> 71 #include <linux/audit.h> 72 #include <linux/string.h> 73 #include <linux/selinux.h> 74 75 #include "avc.h" 76 #include "objsec.h" 77 #include "netif.h" 78 #include "xfrm.h" 79 #include "selinux_netlabel.h" 80 81 #define XATTR_SELINUX_SUFFIX "selinux" 82 #define XATTR_NAME_SELINUX XATTR_SECURITY_PREFIX XATTR_SELINUX_SUFFIX 83 84 extern unsigned int policydb_loaded_version; 85 extern int selinux_nlmsg_lookup(u16 sclass, u16 nlmsg_type, u32 *perm); 86 extern int selinux_compat_net; 87 88 #ifdef CONFIG_SECURITY_SELINUX_DEVELOP 89 int selinux_enforcing = 0; 90 91 static int __init enforcing_setup(char *str) 92 { 93 selinux_enforcing = simple_strtol(str,NULL,0); 94 return 1; 95 } 96 __setup("enforcing=", enforcing_setup); 97 #endif 98 99 #ifdef CONFIG_SECURITY_SELINUX_BOOTPARAM 100 int selinux_enabled = CONFIG_SECURITY_SELINUX_BOOTPARAM_VALUE; 101 102 static int __init selinux_enabled_setup(char *str) 103 { 104 selinux_enabled = simple_strtol(str, NULL, 0); 105 return 1; 106 } 107 __setup("selinux=", selinux_enabled_setup); 108 #else 109 int selinux_enabled = 1; 110 #endif 111 112 /* Original (dummy) security module. */ 113 static struct security_operations *original_ops = NULL; 114 115 /* Minimal support for a secondary security module, 116 just to allow the use of the dummy or capability modules. 117 The owlsm module can alternatively be used as a secondary 118 module as long as CONFIG_OWLSM_FD is not enabled. */ 119 static struct security_operations *secondary_ops = NULL; 120 121 /* Lists of inode and superblock security structures initialized 122 before the policy was loaded. */ 123 static LIST_HEAD(superblock_security_head); 124 static DEFINE_SPINLOCK(sb_security_lock); 125 126 static kmem_cache_t *sel_inode_cache; 127 128 /* Return security context for a given sid or just the context 129 length if the buffer is null or length is 0 */ 130 static int selinux_getsecurity(u32 sid, void *buffer, size_t size) 131 { 132 char *context; 133 unsigned len; 134 int rc; 135 136 rc = security_sid_to_context(sid, &context, &len); 137 if (rc) 138 return rc; 139 140 if (!buffer || !size) 141 goto getsecurity_exit; 142 143 if (size < len) { 144 len = -ERANGE; 145 goto getsecurity_exit; 146 } 147 memcpy(buffer, context, len); 148 149 getsecurity_exit: 150 kfree(context); 151 return len; 152 } 153 154 /* Allocate and free functions for each kind of security blob. */ 155 156 static int task_alloc_security(struct task_struct *task) 157 { 158 struct task_security_struct *tsec; 159 160 tsec = kzalloc(sizeof(struct task_security_struct), GFP_KERNEL); 161 if (!tsec) 162 return -ENOMEM; 163 164 tsec->task = task; 165 tsec->osid = tsec->sid = tsec->ptrace_sid = SECINITSID_UNLABELED; 166 task->security = tsec; 167 168 return 0; 169 } 170 171 static void task_free_security(struct task_struct *task) 172 { 173 struct task_security_struct *tsec = task->security; 174 task->security = NULL; 175 kfree(tsec); 176 } 177 178 static int inode_alloc_security(struct inode *inode) 179 { 180 struct task_security_struct *tsec = current->security; 181 struct inode_security_struct *isec; 182 183 isec = kmem_cache_alloc(sel_inode_cache, SLAB_KERNEL); 184 if (!isec) 185 return -ENOMEM; 186 187 memset(isec, 0, sizeof(*isec)); 188 init_MUTEX(&isec->sem); 189 INIT_LIST_HEAD(&isec->list); 190 isec->inode = inode; 191 isec->sid = SECINITSID_UNLABELED; 192 isec->sclass = SECCLASS_FILE; 193 isec->task_sid = tsec->sid; 194 inode->i_security = isec; 195 196 return 0; 197 } 198 199 static void inode_free_security(struct inode *inode) 200 { 201 struct inode_security_struct *isec = inode->i_security; 202 struct superblock_security_struct *sbsec = inode->i_sb->s_security; 203 204 spin_lock(&sbsec->isec_lock); 205 if (!list_empty(&isec->list)) 206 list_del_init(&isec->list); 207 spin_unlock(&sbsec->isec_lock); 208 209 inode->i_security = NULL; 210 kmem_cache_free(sel_inode_cache, isec); 211 } 212 213 static int file_alloc_security(struct file *file) 214 { 215 struct task_security_struct *tsec = current->security; 216 struct file_security_struct *fsec; 217 218 fsec = kzalloc(sizeof(struct file_security_struct), GFP_KERNEL); 219 if (!fsec) 220 return -ENOMEM; 221 222 fsec->file = file; 223 fsec->sid = tsec->sid; 224 fsec->fown_sid = tsec->sid; 225 file->f_security = fsec; 226 227 return 0; 228 } 229 230 static void file_free_security(struct file *file) 231 { 232 struct file_security_struct *fsec = file->f_security; 233 file->f_security = NULL; 234 kfree(fsec); 235 } 236 237 static int superblock_alloc_security(struct super_block *sb) 238 { 239 struct superblock_security_struct *sbsec; 240 241 sbsec = kzalloc(sizeof(struct superblock_security_struct), GFP_KERNEL); 242 if (!sbsec) 243 return -ENOMEM; 244 245 init_MUTEX(&sbsec->sem); 246 INIT_LIST_HEAD(&sbsec->list); 247 INIT_LIST_HEAD(&sbsec->isec_head); 248 spin_lock_init(&sbsec->isec_lock); 249 sbsec->sb = sb; 250 sbsec->sid = SECINITSID_UNLABELED; 251 sbsec->def_sid = SECINITSID_FILE; 252 sbsec->mntpoint_sid = SECINITSID_UNLABELED; 253 sb->s_security = sbsec; 254 255 return 0; 256 } 257 258 static void superblock_free_security(struct super_block *sb) 259 { 260 struct superblock_security_struct *sbsec = sb->s_security; 261 262 spin_lock(&sb_security_lock); 263 if (!list_empty(&sbsec->list)) 264 list_del_init(&sbsec->list); 265 spin_unlock(&sb_security_lock); 266 267 sb->s_security = NULL; 268 kfree(sbsec); 269 } 270 271 static int sk_alloc_security(struct sock *sk, int family, gfp_t priority) 272 { 273 struct sk_security_struct *ssec; 274 275 ssec = kzalloc(sizeof(*ssec), priority); 276 if (!ssec) 277 return -ENOMEM; 278 279 ssec->sk = sk; 280 ssec->peer_sid = SECINITSID_UNLABELED; 281 ssec->sid = SECINITSID_UNLABELED; 282 sk->sk_security = ssec; 283 284 selinux_netlbl_sk_security_init(ssec, family); 285 286 return 0; 287 } 288 289 static void sk_free_security(struct sock *sk) 290 { 291 struct sk_security_struct *ssec = sk->sk_security; 292 293 sk->sk_security = NULL; 294 kfree(ssec); 295 } 296 297 /* The security server must be initialized before 298 any labeling or access decisions can be provided. */ 299 extern int ss_initialized; 300 301 /* The file system's label must be initialized prior to use. */ 302 303 static char *labeling_behaviors[6] = { 304 "uses xattr", 305 "uses transition SIDs", 306 "uses task SIDs", 307 "uses genfs_contexts", 308 "not configured for labeling", 309 "uses mountpoint labeling", 310 }; 311 312 static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dentry); 313 314 static inline int inode_doinit(struct inode *inode) 315 { 316 return inode_doinit_with_dentry(inode, NULL); 317 } 318 319 enum { 320 Opt_context = 1, 321 Opt_fscontext = 2, 322 Opt_defcontext = 4, 323 Opt_rootcontext = 8, 324 }; 325 326 static match_table_t tokens = { 327 {Opt_context, "context=%s"}, 328 {Opt_fscontext, "fscontext=%s"}, 329 {Opt_defcontext, "defcontext=%s"}, 330 {Opt_rootcontext, "rootcontext=%s"}, 331 }; 332 333 #define SEL_MOUNT_FAIL_MSG "SELinux: duplicate or incompatible mount options\n" 334 335 static int may_context_mount_sb_relabel(u32 sid, 336 struct superblock_security_struct *sbsec, 337 struct task_security_struct *tsec) 338 { 339 int rc; 340 341 rc = avc_has_perm(tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM, 342 FILESYSTEM__RELABELFROM, NULL); 343 if (rc) 344 return rc; 345 346 rc = avc_has_perm(tsec->sid, sid, SECCLASS_FILESYSTEM, 347 FILESYSTEM__RELABELTO, NULL); 348 return rc; 349 } 350 351 static int may_context_mount_inode_relabel(u32 sid, 352 struct superblock_security_struct *sbsec, 353 struct task_security_struct *tsec) 354 { 355 int rc; 356 rc = avc_has_perm(tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM, 357 FILESYSTEM__RELABELFROM, NULL); 358 if (rc) 359 return rc; 360 361 rc = avc_has_perm(sid, sbsec->sid, SECCLASS_FILESYSTEM, 362 FILESYSTEM__ASSOCIATE, NULL); 363 return rc; 364 } 365 366 static int try_context_mount(struct super_block *sb, void *data) 367 { 368 char *context = NULL, *defcontext = NULL; 369 char *fscontext = NULL, *rootcontext = NULL; 370 const char *name; 371 u32 sid; 372 int alloc = 0, rc = 0, seen = 0; 373 struct task_security_struct *tsec = current->security; 374 struct superblock_security_struct *sbsec = sb->s_security; 375 376 if (!data) 377 goto out; 378 379 name = sb->s_type->name; 380 381 if (sb->s_type->fs_flags & FS_BINARY_MOUNTDATA) { 382 383 /* NFS we understand. */ 384 if (!strcmp(name, "nfs")) { 385 struct nfs_mount_data *d = data; 386 387 if (d->version < NFS_MOUNT_VERSION) 388 goto out; 389 390 if (d->context[0]) { 391 context = d->context; 392 seen |= Opt_context; 393 } 394 } else 395 goto out; 396 397 } else { 398 /* Standard string-based options. */ 399 char *p, *options = data; 400 401 while ((p = strsep(&options, ",")) != NULL) { 402 int token; 403 substring_t args[MAX_OPT_ARGS]; 404 405 if (!*p) 406 continue; 407 408 token = match_token(p, tokens, args); 409 410 switch (token) { 411 case Opt_context: 412 if (seen & (Opt_context|Opt_defcontext)) { 413 rc = -EINVAL; 414 printk(KERN_WARNING SEL_MOUNT_FAIL_MSG); 415 goto out_free; 416 } 417 context = match_strdup(&args[0]); 418 if (!context) { 419 rc = -ENOMEM; 420 goto out_free; 421 } 422 if (!alloc) 423 alloc = 1; 424 seen |= Opt_context; 425 break; 426 427 case Opt_fscontext: 428 if (seen & Opt_fscontext) { 429 rc = -EINVAL; 430 printk(KERN_WARNING SEL_MOUNT_FAIL_MSG); 431 goto out_free; 432 } 433 fscontext = match_strdup(&args[0]); 434 if (!fscontext) { 435 rc = -ENOMEM; 436 goto out_free; 437 } 438 if (!alloc) 439 alloc = 1; 440 seen |= Opt_fscontext; 441 break; 442 443 case Opt_rootcontext: 444 if (seen & Opt_rootcontext) { 445 rc = -EINVAL; 446 printk(KERN_WARNING SEL_MOUNT_FAIL_MSG); 447 goto out_free; 448 } 449 rootcontext = match_strdup(&args[0]); 450 if (!rootcontext) { 451 rc = -ENOMEM; 452 goto out_free; 453 } 454 if (!alloc) 455 alloc = 1; 456 seen |= Opt_rootcontext; 457 break; 458 459 case Opt_defcontext: 460 if (sbsec->behavior != SECURITY_FS_USE_XATTR) { 461 rc = -EINVAL; 462 printk(KERN_WARNING "SELinux: " 463 "defcontext option is invalid " 464 "for this filesystem type\n"); 465 goto out_free; 466 } 467 if (seen & (Opt_context|Opt_defcontext)) { 468 rc = -EINVAL; 469 printk(KERN_WARNING SEL_MOUNT_FAIL_MSG); 470 goto out_free; 471 } 472 defcontext = match_strdup(&args[0]); 473 if (!defcontext) { 474 rc = -ENOMEM; 475 goto out_free; 476 } 477 if (!alloc) 478 alloc = 1; 479 seen |= Opt_defcontext; 480 break; 481 482 default: 483 rc = -EINVAL; 484 printk(KERN_WARNING "SELinux: unknown mount " 485 "option\n"); 486 goto out_free; 487 488 } 489 } 490 } 491 492 if (!seen) 493 goto out; 494 495 /* sets the context of the superblock for the fs being mounted. */ 496 if (fscontext) { 497 rc = security_context_to_sid(fscontext, strlen(fscontext), &sid); 498 if (rc) { 499 printk(KERN_WARNING "SELinux: security_context_to_sid" 500 "(%s) failed for (dev %s, type %s) errno=%d\n", 501 fscontext, sb->s_id, name, rc); 502 goto out_free; 503 } 504 505 rc = may_context_mount_sb_relabel(sid, sbsec, tsec); 506 if (rc) 507 goto out_free; 508 509 sbsec->sid = sid; 510 } 511 512 /* 513 * Switch to using mount point labeling behavior. 514 * sets the label used on all file below the mountpoint, and will set 515 * the superblock context if not already set. 516 */ 517 if (context) { 518 rc = security_context_to_sid(context, strlen(context), &sid); 519 if (rc) { 520 printk(KERN_WARNING "SELinux: security_context_to_sid" 521 "(%s) failed for (dev %s, type %s) errno=%d\n", 522 context, sb->s_id, name, rc); 523 goto out_free; 524 } 525 526 if (!fscontext) { 527 rc = may_context_mount_sb_relabel(sid, sbsec, tsec); 528 if (rc) 529 goto out_free; 530 sbsec->sid = sid; 531 } else { 532 rc = may_context_mount_inode_relabel(sid, sbsec, tsec); 533 if (rc) 534 goto out_free; 535 } 536 sbsec->mntpoint_sid = sid; 537 538 sbsec->behavior = SECURITY_FS_USE_MNTPOINT; 539 } 540 541 if (rootcontext) { 542 struct inode *inode = sb->s_root->d_inode; 543 struct inode_security_struct *isec = inode->i_security; 544 rc = security_context_to_sid(rootcontext, strlen(rootcontext), &sid); 545 if (rc) { 546 printk(KERN_WARNING "SELinux: security_context_to_sid" 547 "(%s) failed for (dev %s, type %s) errno=%d\n", 548 rootcontext, sb->s_id, name, rc); 549 goto out_free; 550 } 551 552 rc = may_context_mount_inode_relabel(sid, sbsec, tsec); 553 if (rc) 554 goto out_free; 555 556 isec->sid = sid; 557 isec->initialized = 1; 558 } 559 560 if (defcontext) { 561 rc = security_context_to_sid(defcontext, strlen(defcontext), &sid); 562 if (rc) { 563 printk(KERN_WARNING "SELinux: security_context_to_sid" 564 "(%s) failed for (dev %s, type %s) errno=%d\n", 565 defcontext, sb->s_id, name, rc); 566 goto out_free; 567 } 568 569 if (sid == sbsec->def_sid) 570 goto out_free; 571 572 rc = may_context_mount_inode_relabel(sid, sbsec, tsec); 573 if (rc) 574 goto out_free; 575 576 sbsec->def_sid = sid; 577 } 578 579 out_free: 580 if (alloc) { 581 kfree(context); 582 kfree(defcontext); 583 kfree(fscontext); 584 kfree(rootcontext); 585 } 586 out: 587 return rc; 588 } 589 590 static int superblock_doinit(struct super_block *sb, void *data) 591 { 592 struct superblock_security_struct *sbsec = sb->s_security; 593 struct dentry *root = sb->s_root; 594 struct inode *inode = root->d_inode; 595 int rc = 0; 596 597 down(&sbsec->sem); 598 if (sbsec->initialized) 599 goto out; 600 601 if (!ss_initialized) { 602 /* Defer initialization until selinux_complete_init, 603 after the initial policy is loaded and the security 604 server is ready to handle calls. */ 605 spin_lock(&sb_security_lock); 606 if (list_empty(&sbsec->list)) 607 list_add(&sbsec->list, &superblock_security_head); 608 spin_unlock(&sb_security_lock); 609 goto out; 610 } 611 612 /* Determine the labeling behavior to use for this filesystem type. */ 613 rc = security_fs_use(sb->s_type->name, &sbsec->behavior, &sbsec->sid); 614 if (rc) { 615 printk(KERN_WARNING "%s: security_fs_use(%s) returned %d\n", 616 __FUNCTION__, sb->s_type->name, rc); 617 goto out; 618 } 619 620 rc = try_context_mount(sb, data); 621 if (rc) 622 goto out; 623 624 if (sbsec->behavior == SECURITY_FS_USE_XATTR) { 625 /* Make sure that the xattr handler exists and that no 626 error other than -ENODATA is returned by getxattr on 627 the root directory. -ENODATA is ok, as this may be 628 the first boot of the SELinux kernel before we have 629 assigned xattr values to the filesystem. */ 630 if (!inode->i_op->getxattr) { 631 printk(KERN_WARNING "SELinux: (dev %s, type %s) has no " 632 "xattr support\n", sb->s_id, sb->s_type->name); 633 rc = -EOPNOTSUPP; 634 goto out; 635 } 636 rc = inode->i_op->getxattr(root, XATTR_NAME_SELINUX, NULL, 0); 637 if (rc < 0 && rc != -ENODATA) { 638 if (rc == -EOPNOTSUPP) 639 printk(KERN_WARNING "SELinux: (dev %s, type " 640 "%s) has no security xattr handler\n", 641 sb->s_id, sb->s_type->name); 642 else 643 printk(KERN_WARNING "SELinux: (dev %s, type " 644 "%s) getxattr errno %d\n", sb->s_id, 645 sb->s_type->name, -rc); 646 goto out; 647 } 648 } 649 650 if (strcmp(sb->s_type->name, "proc") == 0) 651 sbsec->proc = 1; 652 653 sbsec->initialized = 1; 654 655 if (sbsec->behavior > ARRAY_SIZE(labeling_behaviors)) { 656 printk(KERN_INFO "SELinux: initialized (dev %s, type %s), unknown behavior\n", 657 sb->s_id, sb->s_type->name); 658 } 659 else { 660 printk(KERN_INFO "SELinux: initialized (dev %s, type %s), %s\n", 661 sb->s_id, sb->s_type->name, 662 labeling_behaviors[sbsec->behavior-1]); 663 } 664 665 /* Initialize the root inode. */ 666 rc = inode_doinit_with_dentry(sb->s_root->d_inode, sb->s_root); 667 668 /* Initialize any other inodes associated with the superblock, e.g. 669 inodes created prior to initial policy load or inodes created 670 during get_sb by a pseudo filesystem that directly 671 populates itself. */ 672 spin_lock(&sbsec->isec_lock); 673 next_inode: 674 if (!list_empty(&sbsec->isec_head)) { 675 struct inode_security_struct *isec = 676 list_entry(sbsec->isec_head.next, 677 struct inode_security_struct, list); 678 struct inode *inode = isec->inode; 679 spin_unlock(&sbsec->isec_lock); 680 inode = igrab(inode); 681 if (inode) { 682 if (!IS_PRIVATE (inode)) 683 inode_doinit(inode); 684 iput(inode); 685 } 686 spin_lock(&sbsec->isec_lock); 687 list_del_init(&isec->list); 688 goto next_inode; 689 } 690 spin_unlock(&sbsec->isec_lock); 691 out: 692 up(&sbsec->sem); 693 return rc; 694 } 695 696 static inline u16 inode_mode_to_security_class(umode_t mode) 697 { 698 switch (mode & S_IFMT) { 699 case S_IFSOCK: 700 return SECCLASS_SOCK_FILE; 701 case S_IFLNK: 702 return SECCLASS_LNK_FILE; 703 case S_IFREG: 704 return SECCLASS_FILE; 705 case S_IFBLK: 706 return SECCLASS_BLK_FILE; 707 case S_IFDIR: 708 return SECCLASS_DIR; 709 case S_IFCHR: 710 return SECCLASS_CHR_FILE; 711 case S_IFIFO: 712 return SECCLASS_FIFO_FILE; 713 714 } 715 716 return SECCLASS_FILE; 717 } 718 719 static inline int default_protocol_stream(int protocol) 720 { 721 return (protocol == IPPROTO_IP || protocol == IPPROTO_TCP); 722 } 723 724 static inline int default_protocol_dgram(int protocol) 725 { 726 return (protocol == IPPROTO_IP || protocol == IPPROTO_UDP); 727 } 728 729 static inline u16 socket_type_to_security_class(int family, int type, int protocol) 730 { 731 switch (family) { 732 case PF_UNIX: 733 switch (type) { 734 case SOCK_STREAM: 735 case SOCK_SEQPACKET: 736 return SECCLASS_UNIX_STREAM_SOCKET; 737 case SOCK_DGRAM: 738 return SECCLASS_UNIX_DGRAM_SOCKET; 739 } 740 break; 741 case PF_INET: 742 case PF_INET6: 743 switch (type) { 744 case SOCK_STREAM: 745 if (default_protocol_stream(protocol)) 746 return SECCLASS_TCP_SOCKET; 747 else 748 return SECCLASS_RAWIP_SOCKET; 749 case SOCK_DGRAM: 750 if (default_protocol_dgram(protocol)) 751 return SECCLASS_UDP_SOCKET; 752 else 753 return SECCLASS_RAWIP_SOCKET; 754 default: 755 return SECCLASS_RAWIP_SOCKET; 756 } 757 break; 758 case PF_NETLINK: 759 switch (protocol) { 760 case NETLINK_ROUTE: 761 return SECCLASS_NETLINK_ROUTE_SOCKET; 762 case NETLINK_FIREWALL: 763 return SECCLASS_NETLINK_FIREWALL_SOCKET; 764 case NETLINK_INET_DIAG: 765 return SECCLASS_NETLINK_TCPDIAG_SOCKET; 766 case NETLINK_NFLOG: 767 return SECCLASS_NETLINK_NFLOG_SOCKET; 768 case NETLINK_XFRM: 769 return SECCLASS_NETLINK_XFRM_SOCKET; 770 case NETLINK_SELINUX: 771 return SECCLASS_NETLINK_SELINUX_SOCKET; 772 case NETLINK_AUDIT: 773 return SECCLASS_NETLINK_AUDIT_SOCKET; 774 case NETLINK_IP6_FW: 775 return SECCLASS_NETLINK_IP6FW_SOCKET; 776 case NETLINK_DNRTMSG: 777 return SECCLASS_NETLINK_DNRT_SOCKET; 778 case NETLINK_KOBJECT_UEVENT: 779 return SECCLASS_NETLINK_KOBJECT_UEVENT_SOCKET; 780 default: 781 return SECCLASS_NETLINK_SOCKET; 782 } 783 case PF_PACKET: 784 return SECCLASS_PACKET_SOCKET; 785 case PF_KEY: 786 return SECCLASS_KEY_SOCKET; 787 case PF_APPLETALK: 788 return SECCLASS_APPLETALK_SOCKET; 789 } 790 791 return SECCLASS_SOCKET; 792 } 793 794 #ifdef CONFIG_PROC_FS 795 static int selinux_proc_get_sid(struct proc_dir_entry *de, 796 u16 tclass, 797 u32 *sid) 798 { 799 int buflen, rc; 800 char *buffer, *path, *end; 801 802 buffer = (char*)__get_free_page(GFP_KERNEL); 803 if (!buffer) 804 return -ENOMEM; 805 806 buflen = PAGE_SIZE; 807 end = buffer+buflen; 808 *--end = '\0'; 809 buflen--; 810 path = end-1; 811 *path = '/'; 812 while (de && de != de->parent) { 813 buflen -= de->namelen + 1; 814 if (buflen < 0) 815 break; 816 end -= de->namelen; 817 memcpy(end, de->name, de->namelen); 818 *--end = '/'; 819 path = end; 820 de = de->parent; 821 } 822 rc = security_genfs_sid("proc", path, tclass, sid); 823 free_page((unsigned long)buffer); 824 return rc; 825 } 826 #else 827 static int selinux_proc_get_sid(struct proc_dir_entry *de, 828 u16 tclass, 829 u32 *sid) 830 { 831 return -EINVAL; 832 } 833 #endif 834 835 /* The inode's security attributes must be initialized before first use. */ 836 static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dentry) 837 { 838 struct superblock_security_struct *sbsec = NULL; 839 struct inode_security_struct *isec = inode->i_security; 840 u32 sid; 841 struct dentry *dentry; 842 #define INITCONTEXTLEN 255 843 char *context = NULL; 844 unsigned len = 0; 845 int rc = 0; 846 int hold_sem = 0; 847 848 if (isec->initialized) 849 goto out; 850 851 down(&isec->sem); 852 hold_sem = 1; 853 if (isec->initialized) 854 goto out; 855 856 sbsec = inode->i_sb->s_security; 857 if (!sbsec->initialized) { 858 /* Defer initialization until selinux_complete_init, 859 after the initial policy is loaded and the security 860 server is ready to handle calls. */ 861 spin_lock(&sbsec->isec_lock); 862 if (list_empty(&isec->list)) 863 list_add(&isec->list, &sbsec->isec_head); 864 spin_unlock(&sbsec->isec_lock); 865 goto out; 866 } 867 868 switch (sbsec->behavior) { 869 case SECURITY_FS_USE_XATTR: 870 if (!inode->i_op->getxattr) { 871 isec->sid = sbsec->def_sid; 872 break; 873 } 874 875 /* Need a dentry, since the xattr API requires one. 876 Life would be simpler if we could just pass the inode. */ 877 if (opt_dentry) { 878 /* Called from d_instantiate or d_splice_alias. */ 879 dentry = dget(opt_dentry); 880 } else { 881 /* Called from selinux_complete_init, try to find a dentry. */ 882 dentry = d_find_alias(inode); 883 } 884 if (!dentry) { 885 printk(KERN_WARNING "%s: no dentry for dev=%s " 886 "ino=%ld\n", __FUNCTION__, inode->i_sb->s_id, 887 inode->i_ino); 888 goto out; 889 } 890 891 len = INITCONTEXTLEN; 892 context = kmalloc(len, GFP_KERNEL); 893 if (!context) { 894 rc = -ENOMEM; 895 dput(dentry); 896 goto out; 897 } 898 rc = inode->i_op->getxattr(dentry, XATTR_NAME_SELINUX, 899 context, len); 900 if (rc == -ERANGE) { 901 /* Need a larger buffer. Query for the right size. */ 902 rc = inode->i_op->getxattr(dentry, XATTR_NAME_SELINUX, 903 NULL, 0); 904 if (rc < 0) { 905 dput(dentry); 906 goto out; 907 } 908 kfree(context); 909 len = rc; 910 context = kmalloc(len, GFP_KERNEL); 911 if (!context) { 912 rc = -ENOMEM; 913 dput(dentry); 914 goto out; 915 } 916 rc = inode->i_op->getxattr(dentry, 917 XATTR_NAME_SELINUX, 918 context, len); 919 } 920 dput(dentry); 921 if (rc < 0) { 922 if (rc != -ENODATA) { 923 printk(KERN_WARNING "%s: getxattr returned " 924 "%d for dev=%s ino=%ld\n", __FUNCTION__, 925 -rc, inode->i_sb->s_id, inode->i_ino); 926 kfree(context); 927 goto out; 928 } 929 /* Map ENODATA to the default file SID */ 930 sid = sbsec->def_sid; 931 rc = 0; 932 } else { 933 rc = security_context_to_sid_default(context, rc, &sid, 934 sbsec->def_sid); 935 if (rc) { 936 printk(KERN_WARNING "%s: context_to_sid(%s) " 937 "returned %d for dev=%s ino=%ld\n", 938 __FUNCTION__, context, -rc, 939 inode->i_sb->s_id, inode->i_ino); 940 kfree(context); 941 /* Leave with the unlabeled SID */ 942 rc = 0; 943 break; 944 } 945 } 946 kfree(context); 947 isec->sid = sid; 948 break; 949 case SECURITY_FS_USE_TASK: 950 isec->sid = isec->task_sid; 951 break; 952 case SECURITY_FS_USE_TRANS: 953 /* Default to the fs SID. */ 954 isec->sid = sbsec->sid; 955 956 /* Try to obtain a transition SID. */ 957 isec->sclass = inode_mode_to_security_class(inode->i_mode); 958 rc = security_transition_sid(isec->task_sid, 959 sbsec->sid, 960 isec->sclass, 961 &sid); 962 if (rc) 963 goto out; 964 isec->sid = sid; 965 break; 966 case SECURITY_FS_USE_MNTPOINT: 967 isec->sid = sbsec->mntpoint_sid; 968 break; 969 default: 970 /* Default to the fs superblock SID. */ 971 isec->sid = sbsec->sid; 972 973 if (sbsec->proc) { 974 struct proc_inode *proci = PROC_I(inode); 975 if (proci->pde) { 976 isec->sclass = inode_mode_to_security_class(inode->i_mode); 977 rc = selinux_proc_get_sid(proci->pde, 978 isec->sclass, 979 &sid); 980 if (rc) 981 goto out; 982 isec->sid = sid; 983 } 984 } 985 break; 986 } 987 988 isec->initialized = 1; 989 990 out: 991 if (isec->sclass == SECCLASS_FILE) 992 isec->sclass = inode_mode_to_security_class(inode->i_mode); 993 994 if (hold_sem) 995 up(&isec->sem); 996 return rc; 997 } 998 999 /* Convert a Linux signal to an access vector. */ 1000 static inline u32 signal_to_av(int sig) 1001 { 1002 u32 perm = 0; 1003 1004 switch (sig) { 1005 case SIGCHLD: 1006 /* Commonly granted from child to parent. */ 1007 perm = PROCESS__SIGCHLD; 1008 break; 1009 case SIGKILL: 1010 /* Cannot be caught or ignored */ 1011 perm = PROCESS__SIGKILL; 1012 break; 1013 case SIGSTOP: 1014 /* Cannot be caught or ignored */ 1015 perm = PROCESS__SIGSTOP; 1016 break; 1017 default: 1018 /* All other signals. */ 1019 perm = PROCESS__SIGNAL; 1020 break; 1021 } 1022 1023 return perm; 1024 } 1025 1026 /* Check permission betweeen a pair of tasks, e.g. signal checks, 1027 fork check, ptrace check, etc. */ 1028 static int task_has_perm(struct task_struct *tsk1, 1029 struct task_struct *tsk2, 1030 u32 perms) 1031 { 1032 struct task_security_struct *tsec1, *tsec2; 1033 1034 tsec1 = tsk1->security; 1035 tsec2 = tsk2->security; 1036 return avc_has_perm(tsec1->sid, tsec2->sid, 1037 SECCLASS_PROCESS, perms, NULL); 1038 } 1039 1040 /* Check whether a task is allowed to use a capability. */ 1041 static int task_has_capability(struct task_struct *tsk, 1042 int cap) 1043 { 1044 struct task_security_struct *tsec; 1045 struct avc_audit_data ad; 1046 1047 tsec = tsk->security; 1048 1049 AVC_AUDIT_DATA_INIT(&ad,CAP); 1050 ad.tsk = tsk; 1051 ad.u.cap = cap; 1052 1053 return avc_has_perm(tsec->sid, tsec->sid, 1054 SECCLASS_CAPABILITY, CAP_TO_MASK(cap), &ad); 1055 } 1056 1057 /* Check whether a task is allowed to use a system operation. */ 1058 static int task_has_system(struct task_struct *tsk, 1059 u32 perms) 1060 { 1061 struct task_security_struct *tsec; 1062 1063 tsec = tsk->security; 1064 1065 return avc_has_perm(tsec->sid, SECINITSID_KERNEL, 1066 SECCLASS_SYSTEM, perms, NULL); 1067 } 1068 1069 /* Check whether a task has a particular permission to an inode. 1070 The 'adp' parameter is optional and allows other audit 1071 data to be passed (e.g. the dentry). */ 1072 static int inode_has_perm(struct task_struct *tsk, 1073 struct inode *inode, 1074 u32 perms, 1075 struct avc_audit_data *adp) 1076 { 1077 struct task_security_struct *tsec; 1078 struct inode_security_struct *isec; 1079 struct avc_audit_data ad; 1080 1081 tsec = tsk->security; 1082 isec = inode->i_security; 1083 1084 if (!adp) { 1085 adp = &ad; 1086 AVC_AUDIT_DATA_INIT(&ad, FS); 1087 ad.u.fs.inode = inode; 1088 } 1089 1090 return avc_has_perm(tsec->sid, isec->sid, isec->sclass, perms, adp); 1091 } 1092 1093 /* Same as inode_has_perm, but pass explicit audit data containing 1094 the dentry to help the auditing code to more easily generate the 1095 pathname if needed. */ 1096 static inline int dentry_has_perm(struct task_struct *tsk, 1097 struct vfsmount *mnt, 1098 struct dentry *dentry, 1099 u32 av) 1100 { 1101 struct inode *inode = dentry->d_inode; 1102 struct avc_audit_data ad; 1103 AVC_AUDIT_DATA_INIT(&ad,FS); 1104 ad.u.fs.mnt = mnt; 1105 ad.u.fs.dentry = dentry; 1106 return inode_has_perm(tsk, inode, av, &ad); 1107 } 1108 1109 /* Check whether a task can use an open file descriptor to 1110 access an inode in a given way. Check access to the 1111 descriptor itself, and then use dentry_has_perm to 1112 check a particular permission to the file. 1113 Access to the descriptor is implicitly granted if it 1114 has the same SID as the process. If av is zero, then 1115 access to the file is not checked, e.g. for cases 1116 where only the descriptor is affected like seek. */ 1117 static int file_has_perm(struct task_struct *tsk, 1118 struct file *file, 1119 u32 av) 1120 { 1121 struct task_security_struct *tsec = tsk->security; 1122 struct file_security_struct *fsec = file->f_security; 1123 struct vfsmount *mnt = file->f_vfsmnt; 1124 struct dentry *dentry = file->f_dentry; 1125 struct inode *inode = dentry->d_inode; 1126 struct avc_audit_data ad; 1127 int rc; 1128 1129 AVC_AUDIT_DATA_INIT(&ad, FS); 1130 ad.u.fs.mnt = mnt; 1131 ad.u.fs.dentry = dentry; 1132 1133 if (tsec->sid != fsec->sid) { 1134 rc = avc_has_perm(tsec->sid, fsec->sid, 1135 SECCLASS_FD, 1136 FD__USE, 1137 &ad); 1138 if (rc) 1139 return rc; 1140 } 1141 1142 /* av is zero if only checking access to the descriptor. */ 1143 if (av) 1144 return inode_has_perm(tsk, inode, av, &ad); 1145 1146 return 0; 1147 } 1148 1149 /* Check whether a task can create a file. */ 1150 static int may_create(struct inode *dir, 1151 struct dentry *dentry, 1152 u16 tclass) 1153 { 1154 struct task_security_struct *tsec; 1155 struct inode_security_struct *dsec; 1156 struct superblock_security_struct *sbsec; 1157 u32 newsid; 1158 struct avc_audit_data ad; 1159 int rc; 1160 1161 tsec = current->security; 1162 dsec = dir->i_security; 1163 sbsec = dir->i_sb->s_security; 1164 1165 AVC_AUDIT_DATA_INIT(&ad, FS); 1166 ad.u.fs.dentry = dentry; 1167 1168 rc = avc_has_perm(tsec->sid, dsec->sid, SECCLASS_DIR, 1169 DIR__ADD_NAME | DIR__SEARCH, 1170 &ad); 1171 if (rc) 1172 return rc; 1173 1174 if (tsec->create_sid && sbsec->behavior != SECURITY_FS_USE_MNTPOINT) { 1175 newsid = tsec->create_sid; 1176 } else { 1177 rc = security_transition_sid(tsec->sid, dsec->sid, tclass, 1178 &newsid); 1179 if (rc) 1180 return rc; 1181 } 1182 1183 rc = avc_has_perm(tsec->sid, newsid, tclass, FILE__CREATE, &ad); 1184 if (rc) 1185 return rc; 1186 1187 return avc_has_perm(newsid, sbsec->sid, 1188 SECCLASS_FILESYSTEM, 1189 FILESYSTEM__ASSOCIATE, &ad); 1190 } 1191 1192 /* Check whether a task can create a key. */ 1193 static int may_create_key(u32 ksid, 1194 struct task_struct *ctx) 1195 { 1196 struct task_security_struct *tsec; 1197 1198 tsec = ctx->security; 1199 1200 return avc_has_perm(tsec->sid, ksid, SECCLASS_KEY, KEY__CREATE, NULL); 1201 } 1202 1203 #define MAY_LINK 0 1204 #define MAY_UNLINK 1 1205 #define MAY_RMDIR 2 1206 1207 /* Check whether a task can link, unlink, or rmdir a file/directory. */ 1208 static int may_link(struct inode *dir, 1209 struct dentry *dentry, 1210 int kind) 1211 1212 { 1213 struct task_security_struct *tsec; 1214 struct inode_security_struct *dsec, *isec; 1215 struct avc_audit_data ad; 1216 u32 av; 1217 int rc; 1218 1219 tsec = current->security; 1220 dsec = dir->i_security; 1221 isec = dentry->d_inode->i_security; 1222 1223 AVC_AUDIT_DATA_INIT(&ad, FS); 1224 ad.u.fs.dentry = dentry; 1225 1226 av = DIR__SEARCH; 1227 av |= (kind ? DIR__REMOVE_NAME : DIR__ADD_NAME); 1228 rc = avc_has_perm(tsec->sid, dsec->sid, SECCLASS_DIR, av, &ad); 1229 if (rc) 1230 return rc; 1231 1232 switch (kind) { 1233 case MAY_LINK: 1234 av = FILE__LINK; 1235 break; 1236 case MAY_UNLINK: 1237 av = FILE__UNLINK; 1238 break; 1239 case MAY_RMDIR: 1240 av = DIR__RMDIR; 1241 break; 1242 default: 1243 printk(KERN_WARNING "may_link: unrecognized kind %d\n", kind); 1244 return 0; 1245 } 1246 1247 rc = avc_has_perm(tsec->sid, isec->sid, isec->sclass, av, &ad); 1248 return rc; 1249 } 1250 1251 static inline int may_rename(struct inode *old_dir, 1252 struct dentry *old_dentry, 1253 struct inode *new_dir, 1254 struct dentry *new_dentry) 1255 { 1256 struct task_security_struct *tsec; 1257 struct inode_security_struct *old_dsec, *new_dsec, *old_isec, *new_isec; 1258 struct avc_audit_data ad; 1259 u32 av; 1260 int old_is_dir, new_is_dir; 1261 int rc; 1262 1263 tsec = current->security; 1264 old_dsec = old_dir->i_security; 1265 old_isec = old_dentry->d_inode->i_security; 1266 old_is_dir = S_ISDIR(old_dentry->d_inode->i_mode); 1267 new_dsec = new_dir->i_security; 1268 1269 AVC_AUDIT_DATA_INIT(&ad, FS); 1270 1271 ad.u.fs.dentry = old_dentry; 1272 rc = avc_has_perm(tsec->sid, old_dsec->sid, SECCLASS_DIR, 1273 DIR__REMOVE_NAME | DIR__SEARCH, &ad); 1274 if (rc) 1275 return rc; 1276 rc = avc_has_perm(tsec->sid, old_isec->sid, 1277 old_isec->sclass, FILE__RENAME, &ad); 1278 if (rc) 1279 return rc; 1280 if (old_is_dir && new_dir != old_dir) { 1281 rc = avc_has_perm(tsec->sid, old_isec->sid, 1282 old_isec->sclass, DIR__REPARENT, &ad); 1283 if (rc) 1284 return rc; 1285 } 1286 1287 ad.u.fs.dentry = new_dentry; 1288 av = DIR__ADD_NAME | DIR__SEARCH; 1289 if (new_dentry->d_inode) 1290 av |= DIR__REMOVE_NAME; 1291 rc = avc_has_perm(tsec->sid, new_dsec->sid, SECCLASS_DIR, av, &ad); 1292 if (rc) 1293 return rc; 1294 if (new_dentry->d_inode) { 1295 new_isec = new_dentry->d_inode->i_security; 1296 new_is_dir = S_ISDIR(new_dentry->d_inode->i_mode); 1297 rc = avc_has_perm(tsec->sid, new_isec->sid, 1298 new_isec->sclass, 1299 (new_is_dir ? DIR__RMDIR : FILE__UNLINK), &ad); 1300 if (rc) 1301 return rc; 1302 } 1303 1304 return 0; 1305 } 1306 1307 /* Check whether a task can perform a filesystem operation. */ 1308 static int superblock_has_perm(struct task_struct *tsk, 1309 struct super_block *sb, 1310 u32 perms, 1311 struct avc_audit_data *ad) 1312 { 1313 struct task_security_struct *tsec; 1314 struct superblock_security_struct *sbsec; 1315 1316 tsec = tsk->security; 1317 sbsec = sb->s_security; 1318 return avc_has_perm(tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM, 1319 perms, ad); 1320 } 1321 1322 /* Convert a Linux mode and permission mask to an access vector. */ 1323 static inline u32 file_mask_to_av(int mode, int mask) 1324 { 1325 u32 av = 0; 1326 1327 if ((mode & S_IFMT) != S_IFDIR) { 1328 if (mask & MAY_EXEC) 1329 av |= FILE__EXECUTE; 1330 if (mask & MAY_READ) 1331 av |= FILE__READ; 1332 1333 if (mask & MAY_APPEND) 1334 av |= FILE__APPEND; 1335 else if (mask & MAY_WRITE) 1336 av |= FILE__WRITE; 1337 1338 } else { 1339 if (mask & MAY_EXEC) 1340 av |= DIR__SEARCH; 1341 if (mask & MAY_WRITE) 1342 av |= DIR__WRITE; 1343 if (mask & MAY_READ) 1344 av |= DIR__READ; 1345 } 1346 1347 return av; 1348 } 1349 1350 /* Convert a Linux file to an access vector. */ 1351 static inline u32 file_to_av(struct file *file) 1352 { 1353 u32 av = 0; 1354 1355 if (file->f_mode & FMODE_READ) 1356 av |= FILE__READ; 1357 if (file->f_mode & FMODE_WRITE) { 1358 if (file->f_flags & O_APPEND) 1359 av |= FILE__APPEND; 1360 else 1361 av |= FILE__WRITE; 1362 } 1363 1364 return av; 1365 } 1366 1367 /* Set an inode's SID to a specified value. */ 1368 static int inode_security_set_sid(struct inode *inode, u32 sid) 1369 { 1370 struct inode_security_struct *isec = inode->i_security; 1371 struct superblock_security_struct *sbsec = inode->i_sb->s_security; 1372 1373 if (!sbsec->initialized) { 1374 /* Defer initialization to selinux_complete_init. */ 1375 return 0; 1376 } 1377 1378 down(&isec->sem); 1379 isec->sclass = inode_mode_to_security_class(inode->i_mode); 1380 isec->sid = sid; 1381 isec->initialized = 1; 1382 up(&isec->sem); 1383 return 0; 1384 } 1385 1386 /* Hook functions begin here. */ 1387 1388 static int selinux_ptrace(struct task_struct *parent, struct task_struct *child) 1389 { 1390 struct task_security_struct *psec = parent->security; 1391 struct task_security_struct *csec = child->security; 1392 int rc; 1393 1394 rc = secondary_ops->ptrace(parent,child); 1395 if (rc) 1396 return rc; 1397 1398 rc = task_has_perm(parent, child, PROCESS__PTRACE); 1399 /* Save the SID of the tracing process for later use in apply_creds. */ 1400 if (!(child->ptrace & PT_PTRACED) && !rc) 1401 csec->ptrace_sid = psec->sid; 1402 return rc; 1403 } 1404 1405 static int selinux_capget(struct task_struct *target, kernel_cap_t *effective, 1406 kernel_cap_t *inheritable, kernel_cap_t *permitted) 1407 { 1408 int error; 1409 1410 error = task_has_perm(current, target, PROCESS__GETCAP); 1411 if (error) 1412 return error; 1413 1414 return secondary_ops->capget(target, effective, inheritable, permitted); 1415 } 1416 1417 static int selinux_capset_check(struct task_struct *target, kernel_cap_t *effective, 1418 kernel_cap_t *inheritable, kernel_cap_t *permitted) 1419 { 1420 int error; 1421 1422 error = secondary_ops->capset_check(target, effective, inheritable, permitted); 1423 if (error) 1424 return error; 1425 1426 return task_has_perm(current, target, PROCESS__SETCAP); 1427 } 1428 1429 static void selinux_capset_set(struct task_struct *target, kernel_cap_t *effective, 1430 kernel_cap_t *inheritable, kernel_cap_t *permitted) 1431 { 1432 secondary_ops->capset_set(target, effective, inheritable, permitted); 1433 } 1434 1435 static int selinux_capable(struct task_struct *tsk, int cap) 1436 { 1437 int rc; 1438 1439 rc = secondary_ops->capable(tsk, cap); 1440 if (rc) 1441 return rc; 1442 1443 return task_has_capability(tsk,cap); 1444 } 1445 1446 static int selinux_sysctl(ctl_table *table, int op) 1447 { 1448 int error = 0; 1449 u32 av; 1450 struct task_security_struct *tsec; 1451 u32 tsid; 1452 int rc; 1453 1454 rc = secondary_ops->sysctl(table, op); 1455 if (rc) 1456 return rc; 1457 1458 tsec = current->security; 1459 1460 rc = selinux_proc_get_sid(table->de, (op == 001) ? 1461 SECCLASS_DIR : SECCLASS_FILE, &tsid); 1462 if (rc) { 1463 /* Default to the well-defined sysctl SID. */ 1464 tsid = SECINITSID_SYSCTL; 1465 } 1466 1467 /* The op values are "defined" in sysctl.c, thereby creating 1468 * a bad coupling between this module and sysctl.c */ 1469 if(op == 001) { 1470 error = avc_has_perm(tsec->sid, tsid, 1471 SECCLASS_DIR, DIR__SEARCH, NULL); 1472 } else { 1473 av = 0; 1474 if (op & 004) 1475 av |= FILE__READ; 1476 if (op & 002) 1477 av |= FILE__WRITE; 1478 if (av) 1479 error = avc_has_perm(tsec->sid, tsid, 1480 SECCLASS_FILE, av, NULL); 1481 } 1482 1483 return error; 1484 } 1485 1486 static int selinux_quotactl(int cmds, int type, int id, struct super_block *sb) 1487 { 1488 int rc = 0; 1489 1490 if (!sb) 1491 return 0; 1492 1493 switch (cmds) { 1494 case Q_SYNC: 1495 case Q_QUOTAON: 1496 case Q_QUOTAOFF: 1497 case Q_SETINFO: 1498 case Q_SETQUOTA: 1499 rc = superblock_has_perm(current, 1500 sb, 1501 FILESYSTEM__QUOTAMOD, NULL); 1502 break; 1503 case Q_GETFMT: 1504 case Q_GETINFO: 1505 case Q_GETQUOTA: 1506 rc = superblock_has_perm(current, 1507 sb, 1508 FILESYSTEM__QUOTAGET, NULL); 1509 break; 1510 default: 1511 rc = 0; /* let the kernel handle invalid cmds */ 1512 break; 1513 } 1514 return rc; 1515 } 1516 1517 static int selinux_quota_on(struct dentry *dentry) 1518 { 1519 return dentry_has_perm(current, NULL, dentry, FILE__QUOTAON); 1520 } 1521 1522 static int selinux_syslog(int type) 1523 { 1524 int rc; 1525 1526 rc = secondary_ops->syslog(type); 1527 if (rc) 1528 return rc; 1529 1530 switch (type) { 1531 case 3: /* Read last kernel messages */ 1532 case 10: /* Return size of the log buffer */ 1533 rc = task_has_system(current, SYSTEM__SYSLOG_READ); 1534 break; 1535 case 6: /* Disable logging to console */ 1536 case 7: /* Enable logging to console */ 1537 case 8: /* Set level of messages printed to console */ 1538 rc = task_has_system(current, SYSTEM__SYSLOG_CONSOLE); 1539 break; 1540 case 0: /* Close log */ 1541 case 1: /* Open log */ 1542 case 2: /* Read from log */ 1543 case 4: /* Read/clear last kernel messages */ 1544 case 5: /* Clear ring buffer */ 1545 default: 1546 rc = task_has_system(current, SYSTEM__SYSLOG_MOD); 1547 break; 1548 } 1549 return rc; 1550 } 1551 1552 /* 1553 * Check that a process has enough memory to allocate a new virtual 1554 * mapping. 0 means there is enough memory for the allocation to 1555 * succeed and -ENOMEM implies there is not. 1556 * 1557 * Note that secondary_ops->capable and task_has_perm_noaudit return 0 1558 * if the capability is granted, but __vm_enough_memory requires 1 if 1559 * the capability is granted. 1560 * 1561 * Do not audit the selinux permission check, as this is applied to all 1562 * processes that allocate mappings. 1563 */ 1564 static int selinux_vm_enough_memory(long pages) 1565 { 1566 int rc, cap_sys_admin = 0; 1567 struct task_security_struct *tsec = current->security; 1568 1569 rc = secondary_ops->capable(current, CAP_SYS_ADMIN); 1570 if (rc == 0) 1571 rc = avc_has_perm_noaudit(tsec->sid, tsec->sid, 1572 SECCLASS_CAPABILITY, 1573 CAP_TO_MASK(CAP_SYS_ADMIN), 1574 NULL); 1575 1576 if (rc == 0) 1577 cap_sys_admin = 1; 1578 1579 return __vm_enough_memory(pages, cap_sys_admin); 1580 } 1581 1582 /* binprm security operations */ 1583 1584 static int selinux_bprm_alloc_security(struct linux_binprm *bprm) 1585 { 1586 struct bprm_security_struct *bsec; 1587 1588 bsec = kzalloc(sizeof(struct bprm_security_struct), GFP_KERNEL); 1589 if (!bsec) 1590 return -ENOMEM; 1591 1592 bsec->bprm = bprm; 1593 bsec->sid = SECINITSID_UNLABELED; 1594 bsec->set = 0; 1595 1596 bprm->security = bsec; 1597 return 0; 1598 } 1599 1600 static int selinux_bprm_set_security(struct linux_binprm *bprm) 1601 { 1602 struct task_security_struct *tsec; 1603 struct inode *inode = bprm->file->f_dentry->d_inode; 1604 struct inode_security_struct *isec; 1605 struct bprm_security_struct *bsec; 1606 u32 newsid; 1607 struct avc_audit_data ad; 1608 int rc; 1609 1610 rc = secondary_ops->bprm_set_security(bprm); 1611 if (rc) 1612 return rc; 1613 1614 bsec = bprm->security; 1615 1616 if (bsec->set) 1617 return 0; 1618 1619 tsec = current->security; 1620 isec = inode->i_security; 1621 1622 /* Default to the current task SID. */ 1623 bsec->sid = tsec->sid; 1624 1625 /* Reset fs, key, and sock SIDs on execve. */ 1626 tsec->create_sid = 0; 1627 tsec->keycreate_sid = 0; 1628 tsec->sockcreate_sid = 0; 1629 1630 if (tsec->exec_sid) { 1631 newsid = tsec->exec_sid; 1632 /* Reset exec SID on execve. */ 1633 tsec->exec_sid = 0; 1634 } else { 1635 /* Check for a default transition on this program. */ 1636 rc = security_transition_sid(tsec->sid, isec->sid, 1637 SECCLASS_PROCESS, &newsid); 1638 if (rc) 1639 return rc; 1640 } 1641 1642 AVC_AUDIT_DATA_INIT(&ad, FS); 1643 ad.u.fs.mnt = bprm->file->f_vfsmnt; 1644 ad.u.fs.dentry = bprm->file->f_dentry; 1645 1646 if (bprm->file->f_vfsmnt->mnt_flags & MNT_NOSUID) 1647 newsid = tsec->sid; 1648 1649 if (tsec->sid == newsid) { 1650 rc = avc_has_perm(tsec->sid, isec->sid, 1651 SECCLASS_FILE, FILE__EXECUTE_NO_TRANS, &ad); 1652 if (rc) 1653 return rc; 1654 } else { 1655 /* Check permissions for the transition. */ 1656 rc = avc_has_perm(tsec->sid, newsid, 1657 SECCLASS_PROCESS, PROCESS__TRANSITION, &ad); 1658 if (rc) 1659 return rc; 1660 1661 rc = avc_has_perm(newsid, isec->sid, 1662 SECCLASS_FILE, FILE__ENTRYPOINT, &ad); 1663 if (rc) 1664 return rc; 1665 1666 /* Clear any possibly unsafe personality bits on exec: */ 1667 current->personality &= ~PER_CLEAR_ON_SETID; 1668 1669 /* Set the security field to the new SID. */ 1670 bsec->sid = newsid; 1671 } 1672 1673 bsec->set = 1; 1674 return 0; 1675 } 1676 1677 static int selinux_bprm_check_security (struct linux_binprm *bprm) 1678 { 1679 return secondary_ops->bprm_check_security(bprm); 1680 } 1681 1682 1683 static int selinux_bprm_secureexec (struct linux_binprm *bprm) 1684 { 1685 struct task_security_struct *tsec = current->security; 1686 int atsecure = 0; 1687 1688 if (tsec->osid != tsec->sid) { 1689 /* Enable secure mode for SIDs transitions unless 1690 the noatsecure permission is granted between 1691 the two SIDs, i.e. ahp returns 0. */ 1692 atsecure = avc_has_perm(tsec->osid, tsec->sid, 1693 SECCLASS_PROCESS, 1694 PROCESS__NOATSECURE, NULL); 1695 } 1696 1697 return (atsecure || secondary_ops->bprm_secureexec(bprm)); 1698 } 1699 1700 static void selinux_bprm_free_security(struct linux_binprm *bprm) 1701 { 1702 kfree(bprm->security); 1703 bprm->security = NULL; 1704 } 1705 1706 extern struct vfsmount *selinuxfs_mount; 1707 extern struct dentry *selinux_null; 1708 1709 /* Derived from fs/exec.c:flush_old_files. */ 1710 static inline void flush_unauthorized_files(struct files_struct * files) 1711 { 1712 struct avc_audit_data ad; 1713 struct file *file, *devnull = NULL; 1714 struct tty_struct *tty = current->signal->tty; 1715 struct fdtable *fdt; 1716 long j = -1; 1717 1718 if (tty) { 1719 file_list_lock(); 1720 file = list_entry(tty->tty_files.next, typeof(*file), f_u.fu_list); 1721 if (file) { 1722 /* Revalidate access to controlling tty. 1723 Use inode_has_perm on the tty inode directly rather 1724 than using file_has_perm, as this particular open 1725 file may belong to another process and we are only 1726 interested in the inode-based check here. */ 1727 struct inode *inode = file->f_dentry->d_inode; 1728 if (inode_has_perm(current, inode, 1729 FILE__READ | FILE__WRITE, NULL)) { 1730 /* Reset controlling tty. */ 1731 current->signal->tty = NULL; 1732 current->signal->tty_old_pgrp = 0; 1733 } 1734 } 1735 file_list_unlock(); 1736 } 1737 1738 /* Revalidate access to inherited open files. */ 1739 1740 AVC_AUDIT_DATA_INIT(&ad,FS); 1741 1742 spin_lock(&files->file_lock); 1743 for (;;) { 1744 unsigned long set, i; 1745 int fd; 1746 1747 j++; 1748 i = j * __NFDBITS; 1749 fdt = files_fdtable(files); 1750 if (i >= fdt->max_fds || i >= fdt->max_fdset) 1751 break; 1752 set = fdt->open_fds->fds_bits[j]; 1753 if (!set) 1754 continue; 1755 spin_unlock(&files->file_lock); 1756 for ( ; set ; i++,set >>= 1) { 1757 if (set & 1) { 1758 file = fget(i); 1759 if (!file) 1760 continue; 1761 if (file_has_perm(current, 1762 file, 1763 file_to_av(file))) { 1764 sys_close(i); 1765 fd = get_unused_fd(); 1766 if (fd != i) { 1767 if (fd >= 0) 1768 put_unused_fd(fd); 1769 fput(file); 1770 continue; 1771 } 1772 if (devnull) { 1773 get_file(devnull); 1774 } else { 1775 devnull = dentry_open(dget(selinux_null), mntget(selinuxfs_mount), O_RDWR); 1776 if (!devnull) { 1777 put_unused_fd(fd); 1778 fput(file); 1779 continue; 1780 } 1781 } 1782 fd_install(fd, devnull); 1783 } 1784 fput(file); 1785 } 1786 } 1787 spin_lock(&files->file_lock); 1788 1789 } 1790 spin_unlock(&files->file_lock); 1791 } 1792 1793 static void selinux_bprm_apply_creds(struct linux_binprm *bprm, int unsafe) 1794 { 1795 struct task_security_struct *tsec; 1796 struct bprm_security_struct *bsec; 1797 u32 sid; 1798 int rc; 1799 1800 secondary_ops->bprm_apply_creds(bprm, unsafe); 1801 1802 tsec = current->security; 1803 1804 bsec = bprm->security; 1805 sid = bsec->sid; 1806 1807 tsec->osid = tsec->sid; 1808 bsec->unsafe = 0; 1809 if (tsec->sid != sid) { 1810 /* Check for shared state. If not ok, leave SID 1811 unchanged and kill. */ 1812 if (unsafe & LSM_UNSAFE_SHARE) { 1813 rc = avc_has_perm(tsec->sid, sid, SECCLASS_PROCESS, 1814 PROCESS__SHARE, NULL); 1815 if (rc) { 1816 bsec->unsafe = 1; 1817 return; 1818 } 1819 } 1820 1821 /* Check for ptracing, and update the task SID if ok. 1822 Otherwise, leave SID unchanged and kill. */ 1823 if (unsafe & (LSM_UNSAFE_PTRACE | LSM_UNSAFE_PTRACE_CAP)) { 1824 rc = avc_has_perm(tsec->ptrace_sid, sid, 1825 SECCLASS_PROCESS, PROCESS__PTRACE, 1826 NULL); 1827 if (rc) { 1828 bsec->unsafe = 1; 1829 return; 1830 } 1831 } 1832 tsec->sid = sid; 1833 } 1834 } 1835 1836 /* 1837 * called after apply_creds without the task lock held 1838 */ 1839 static void selinux_bprm_post_apply_creds(struct linux_binprm *bprm) 1840 { 1841 struct task_security_struct *tsec; 1842 struct rlimit *rlim, *initrlim; 1843 struct itimerval itimer; 1844 struct bprm_security_struct *bsec; 1845 int rc, i; 1846 1847 tsec = current->security; 1848 bsec = bprm->security; 1849 1850 if (bsec->unsafe) { 1851 force_sig_specific(SIGKILL, current); 1852 return; 1853 } 1854 if (tsec->osid == tsec->sid) 1855 return; 1856 1857 /* Close files for which the new task SID is not authorized. */ 1858 flush_unauthorized_files(current->files); 1859 1860 /* Check whether the new SID can inherit signal state 1861 from the old SID. If not, clear itimers to avoid 1862 subsequent signal generation and flush and unblock 1863 signals. This must occur _after_ the task SID has 1864 been updated so that any kill done after the flush 1865 will be checked against the new SID. */ 1866 rc = avc_has_perm(tsec->osid, tsec->sid, SECCLASS_PROCESS, 1867 PROCESS__SIGINH, NULL); 1868 if (rc) { 1869 memset(&itimer, 0, sizeof itimer); 1870 for (i = 0; i < 3; i++) 1871 do_setitimer(i, &itimer, NULL); 1872 flush_signals(current); 1873 spin_lock_irq(¤t->sighand->siglock); 1874 flush_signal_handlers(current, 1); 1875 sigemptyset(¤t->blocked); 1876 recalc_sigpending(); 1877 spin_unlock_irq(¤t->sighand->siglock); 1878 } 1879 1880 /* Check whether the new SID can inherit resource limits 1881 from the old SID. If not, reset all soft limits to 1882 the lower of the current task's hard limit and the init 1883 task's soft limit. Note that the setting of hard limits 1884 (even to lower them) can be controlled by the setrlimit 1885 check. The inclusion of the init task's soft limit into 1886 the computation is to avoid resetting soft limits higher 1887 than the default soft limit for cases where the default 1888 is lower than the hard limit, e.g. RLIMIT_CORE or 1889 RLIMIT_STACK.*/ 1890 rc = avc_has_perm(tsec->osid, tsec->sid, SECCLASS_PROCESS, 1891 PROCESS__RLIMITINH, NULL); 1892 if (rc) { 1893 for (i = 0; i < RLIM_NLIMITS; i++) { 1894 rlim = current->signal->rlim + i; 1895 initrlim = init_task.signal->rlim+i; 1896 rlim->rlim_cur = min(rlim->rlim_max,initrlim->rlim_cur); 1897 } 1898 if (current->signal->rlim[RLIMIT_CPU].rlim_cur != RLIM_INFINITY) { 1899 /* 1900 * This will cause RLIMIT_CPU calculations 1901 * to be refigured. 1902 */ 1903 current->it_prof_expires = jiffies_to_cputime(1); 1904 } 1905 } 1906 1907 /* Wake up the parent if it is waiting so that it can 1908 recheck wait permission to the new task SID. */ 1909 wake_up_interruptible(¤t->parent->signal->wait_chldexit); 1910 } 1911 1912 /* superblock security operations */ 1913 1914 static int selinux_sb_alloc_security(struct super_block *sb) 1915 { 1916 return superblock_alloc_security(sb); 1917 } 1918 1919 static void selinux_sb_free_security(struct super_block *sb) 1920 { 1921 superblock_free_security(sb); 1922 } 1923 1924 static inline int match_prefix(char *prefix, int plen, char *option, int olen) 1925 { 1926 if (plen > olen) 1927 return 0; 1928 1929 return !memcmp(prefix, option, plen); 1930 } 1931 1932 static inline int selinux_option(char *option, int len) 1933 { 1934 return (match_prefix("context=", sizeof("context=")-1, option, len) || 1935 match_prefix("fscontext=", sizeof("fscontext=")-1, option, len) || 1936 match_prefix("defcontext=", sizeof("defcontext=")-1, option, len) || 1937 match_prefix("rootcontext=", sizeof("rootcontext=")-1, option, len)); 1938 } 1939 1940 static inline void take_option(char **to, char *from, int *first, int len) 1941 { 1942 if (!*first) { 1943 **to = ','; 1944 *to += 1; 1945 } 1946 else 1947 *first = 0; 1948 memcpy(*to, from, len); 1949 *to += len; 1950 } 1951 1952 static int selinux_sb_copy_data(struct file_system_type *type, void *orig, void *copy) 1953 { 1954 int fnosec, fsec, rc = 0; 1955 char *in_save, *in_curr, *in_end; 1956 char *sec_curr, *nosec_save, *nosec; 1957 1958 in_curr = orig; 1959 sec_curr = copy; 1960 1961 /* Binary mount data: just copy */ 1962 if (type->fs_flags & FS_BINARY_MOUNTDATA) { 1963 copy_page(sec_curr, in_curr); 1964 goto out; 1965 } 1966 1967 nosec = (char *)get_zeroed_page(GFP_KERNEL); 1968 if (!nosec) { 1969 rc = -ENOMEM; 1970 goto out; 1971 } 1972 1973 nosec_save = nosec; 1974 fnosec = fsec = 1; 1975 in_save = in_end = orig; 1976 1977 do { 1978 if (*in_end == ',' || *in_end == '\0') { 1979 int len = in_end - in_curr; 1980 1981 if (selinux_option(in_curr, len)) 1982 take_option(&sec_curr, in_curr, &fsec, len); 1983 else 1984 take_option(&nosec, in_curr, &fnosec, len); 1985 1986 in_curr = in_end + 1; 1987 } 1988 } while (*in_end++); 1989 1990 strcpy(in_save, nosec_save); 1991 free_page((unsigned long)nosec_save); 1992 out: 1993 return rc; 1994 } 1995 1996 static int selinux_sb_kern_mount(struct super_block *sb, void *data) 1997 { 1998 struct avc_audit_data ad; 1999 int rc; 2000 2001 rc = superblock_doinit(sb, data); 2002 if (rc) 2003 return rc; 2004 2005 AVC_AUDIT_DATA_INIT(&ad,FS); 2006 ad.u.fs.dentry = sb->s_root; 2007 return superblock_has_perm(current, sb, FILESYSTEM__MOUNT, &ad); 2008 } 2009 2010 static int selinux_sb_statfs(struct dentry *dentry) 2011 { 2012 struct avc_audit_data ad; 2013 2014 AVC_AUDIT_DATA_INIT(&ad,FS); 2015 ad.u.fs.dentry = dentry->d_sb->s_root; 2016 return superblock_has_perm(current, dentry->d_sb, FILESYSTEM__GETATTR, &ad); 2017 } 2018 2019 static int selinux_mount(char * dev_name, 2020 struct nameidata *nd, 2021 char * type, 2022 unsigned long flags, 2023 void * data) 2024 { 2025 int rc; 2026 2027 rc = secondary_ops->sb_mount(dev_name, nd, type, flags, data); 2028 if (rc) 2029 return rc; 2030 2031 if (flags & MS_REMOUNT) 2032 return superblock_has_perm(current, nd->mnt->mnt_sb, 2033 FILESYSTEM__REMOUNT, NULL); 2034 else 2035 return dentry_has_perm(current, nd->mnt, nd->dentry, 2036 FILE__MOUNTON); 2037 } 2038 2039 static int selinux_umount(struct vfsmount *mnt, int flags) 2040 { 2041 int rc; 2042 2043 rc = secondary_ops->sb_umount(mnt, flags); 2044 if (rc) 2045 return rc; 2046 2047 return superblock_has_perm(current,mnt->mnt_sb, 2048 FILESYSTEM__UNMOUNT,NULL); 2049 } 2050 2051 /* inode security operations */ 2052 2053 static int selinux_inode_alloc_security(struct inode *inode) 2054 { 2055 return inode_alloc_security(inode); 2056 } 2057 2058 static void selinux_inode_free_security(struct inode *inode) 2059 { 2060 inode_free_security(inode); 2061 } 2062 2063 static int selinux_inode_init_security(struct inode *inode, struct inode *dir, 2064 char **name, void **value, 2065 size_t *len) 2066 { 2067 struct task_security_struct *tsec; 2068 struct inode_security_struct *dsec; 2069 struct superblock_security_struct *sbsec; 2070 u32 newsid, clen; 2071 int rc; 2072 char *namep = NULL, *context; 2073 2074 tsec = current->security; 2075 dsec = dir->i_security; 2076 sbsec = dir->i_sb->s_security; 2077 2078 if (tsec->create_sid && sbsec->behavior != SECURITY_FS_USE_MNTPOINT) { 2079 newsid = tsec->create_sid; 2080 } else { 2081 rc = security_transition_sid(tsec->sid, dsec->sid, 2082 inode_mode_to_security_class(inode->i_mode), 2083 &newsid); 2084 if (rc) { 2085 printk(KERN_WARNING "%s: " 2086 "security_transition_sid failed, rc=%d (dev=%s " 2087 "ino=%ld)\n", 2088 __FUNCTION__, 2089 -rc, inode->i_sb->s_id, inode->i_ino); 2090 return rc; 2091 } 2092 } 2093 2094 inode_security_set_sid(inode, newsid); 2095 2096 if (!ss_initialized || sbsec->behavior == SECURITY_FS_USE_MNTPOINT) 2097 return -EOPNOTSUPP; 2098 2099 if (name) { 2100 namep = kstrdup(XATTR_SELINUX_SUFFIX, GFP_KERNEL); 2101 if (!namep) 2102 return -ENOMEM; 2103 *name = namep; 2104 } 2105 2106 if (value && len) { 2107 rc = security_sid_to_context(newsid, &context, &clen); 2108 if (rc) { 2109 kfree(namep); 2110 return rc; 2111 } 2112 *value = context; 2113 *len = clen; 2114 } 2115 2116 return 0; 2117 } 2118 2119 static int selinux_inode_create(struct inode *dir, struct dentry *dentry, int mask) 2120 { 2121 return may_create(dir, dentry, SECCLASS_FILE); 2122 } 2123 2124 static int selinux_inode_link(struct dentry *old_dentry, struct inode *dir, struct dentry *new_dentry) 2125 { 2126 int rc; 2127 2128 rc = secondary_ops->inode_link(old_dentry,dir,new_dentry); 2129 if (rc) 2130 return rc; 2131 return may_link(dir, old_dentry, MAY_LINK); 2132 } 2133 2134 static int selinux_inode_unlink(struct inode *dir, struct dentry *dentry) 2135 { 2136 int rc; 2137 2138 rc = secondary_ops->inode_unlink(dir, dentry); 2139 if (rc) 2140 return rc; 2141 return may_link(dir, dentry, MAY_UNLINK); 2142 } 2143 2144 static int selinux_inode_symlink(struct inode *dir, struct dentry *dentry, const char *name) 2145 { 2146 return may_create(dir, dentry, SECCLASS_LNK_FILE); 2147 } 2148 2149 static int selinux_inode_mkdir(struct inode *dir, struct dentry *dentry, int mask) 2150 { 2151 return may_create(dir, dentry, SECCLASS_DIR); 2152 } 2153 2154 static int selinux_inode_rmdir(struct inode *dir, struct dentry *dentry) 2155 { 2156 return may_link(dir, dentry, MAY_RMDIR); 2157 } 2158 2159 static int selinux_inode_mknod(struct inode *dir, struct dentry *dentry, int mode, dev_t dev) 2160 { 2161 int rc; 2162 2163 rc = secondary_ops->inode_mknod(dir, dentry, mode, dev); 2164 if (rc) 2165 return rc; 2166 2167 return may_create(dir, dentry, inode_mode_to_security_class(mode)); 2168 } 2169 2170 static int selinux_inode_rename(struct inode *old_inode, struct dentry *old_dentry, 2171 struct inode *new_inode, struct dentry *new_dentry) 2172 { 2173 return may_rename(old_inode, old_dentry, new_inode, new_dentry); 2174 } 2175 2176 static int selinux_inode_readlink(struct dentry *dentry) 2177 { 2178 return dentry_has_perm(current, NULL, dentry, FILE__READ); 2179 } 2180 2181 static int selinux_inode_follow_link(struct dentry *dentry, struct nameidata *nameidata) 2182 { 2183 int rc; 2184 2185 rc = secondary_ops->inode_follow_link(dentry,nameidata); 2186 if (rc) 2187 return rc; 2188 return dentry_has_perm(current, NULL, dentry, FILE__READ); 2189 } 2190 2191 static int selinux_inode_permission(struct inode *inode, int mask, 2192 struct nameidata *nd) 2193 { 2194 int rc; 2195 2196 rc = secondary_ops->inode_permission(inode, mask, nd); 2197 if (rc) 2198 return rc; 2199 2200 if (!mask) { 2201 /* No permission to check. Existence test. */ 2202 return 0; 2203 } 2204 2205 return inode_has_perm(current, inode, 2206 file_mask_to_av(inode->i_mode, mask), NULL); 2207 } 2208 2209 static int selinux_inode_setattr(struct dentry *dentry, struct iattr *iattr) 2210 { 2211 int rc; 2212 2213 rc = secondary_ops->inode_setattr(dentry, iattr); 2214 if (rc) 2215 return rc; 2216 2217 if (iattr->ia_valid & ATTR_FORCE) 2218 return 0; 2219 2220 if (iattr->ia_valid & (ATTR_MODE | ATTR_UID | ATTR_GID | 2221 ATTR_ATIME_SET | ATTR_MTIME_SET)) 2222 return dentry_has_perm(current, NULL, dentry, FILE__SETATTR); 2223 2224 return dentry_has_perm(current, NULL, dentry, FILE__WRITE); 2225 } 2226 2227 static int selinux_inode_getattr(struct vfsmount *mnt, struct dentry *dentry) 2228 { 2229 return dentry_has_perm(current, mnt, dentry, FILE__GETATTR); 2230 } 2231 2232 static int selinux_inode_setxattr(struct dentry *dentry, char *name, void *value, size_t size, int flags) 2233 { 2234 struct task_security_struct *tsec = current->security; 2235 struct inode *inode = dentry->d_inode; 2236 struct inode_security_struct *isec = inode->i_security; 2237 struct superblock_security_struct *sbsec; 2238 struct avc_audit_data ad; 2239 u32 newsid; 2240 int rc = 0; 2241 2242 if (strcmp(name, XATTR_NAME_SELINUX)) { 2243 if (!strncmp(name, XATTR_SECURITY_PREFIX, 2244 sizeof XATTR_SECURITY_PREFIX - 1) && 2245 !capable(CAP_SYS_ADMIN)) { 2246 /* A different attribute in the security namespace. 2247 Restrict to administrator. */ 2248 return -EPERM; 2249 } 2250 2251 /* Not an attribute we recognize, so just check the 2252 ordinary setattr permission. */ 2253 return dentry_has_perm(current, NULL, dentry, FILE__SETATTR); 2254 } 2255 2256 sbsec = inode->i_sb->s_security; 2257 if (sbsec->behavior == SECURITY_FS_USE_MNTPOINT) 2258 return -EOPNOTSUPP; 2259 2260 if ((current->fsuid != inode->i_uid) && !capable(CAP_FOWNER)) 2261 return -EPERM; 2262 2263 AVC_AUDIT_DATA_INIT(&ad,FS); 2264 ad.u.fs.dentry = dentry; 2265 2266 rc = avc_has_perm(tsec->sid, isec->sid, isec->sclass, 2267 FILE__RELABELFROM, &ad); 2268 if (rc) 2269 return rc; 2270 2271 rc = security_context_to_sid(value, size, &newsid); 2272 if (rc) 2273 return rc; 2274 2275 rc = avc_has_perm(tsec->sid, newsid, isec->sclass, 2276 FILE__RELABELTO, &ad); 2277 if (rc) 2278 return rc; 2279 2280 rc = security_validate_transition(isec->sid, newsid, tsec->sid, 2281 isec->sclass); 2282 if (rc) 2283 return rc; 2284 2285 return avc_has_perm(newsid, 2286 sbsec->sid, 2287 SECCLASS_FILESYSTEM, 2288 FILESYSTEM__ASSOCIATE, 2289 &ad); 2290 } 2291 2292 static void selinux_inode_post_setxattr(struct dentry *dentry, char *name, 2293 void *value, size_t size, int flags) 2294 { 2295 struct inode *inode = dentry->d_inode; 2296 struct inode_security_struct *isec = inode->i_security; 2297 u32 newsid; 2298 int rc; 2299 2300 if (strcmp(name, XATTR_NAME_SELINUX)) { 2301 /* Not an attribute we recognize, so nothing to do. */ 2302 return; 2303 } 2304 2305 rc = security_context_to_sid(value, size, &newsid); 2306 if (rc) { 2307 printk(KERN_WARNING "%s: unable to obtain SID for context " 2308 "%s, rc=%d\n", __FUNCTION__, (char*)value, -rc); 2309 return; 2310 } 2311 2312 isec->sid = newsid; 2313 return; 2314 } 2315 2316 static int selinux_inode_getxattr (struct dentry *dentry, char *name) 2317 { 2318 return dentry_has_perm(current, NULL, dentry, FILE__GETATTR); 2319 } 2320 2321 static int selinux_inode_listxattr (struct dentry *dentry) 2322 { 2323 return dentry_has_perm(current, NULL, dentry, FILE__GETATTR); 2324 } 2325 2326 static int selinux_inode_removexattr (struct dentry *dentry, char *name) 2327 { 2328 if (strcmp(name, XATTR_NAME_SELINUX)) { 2329 if (!strncmp(name, XATTR_SECURITY_PREFIX, 2330 sizeof XATTR_SECURITY_PREFIX - 1) && 2331 !capable(CAP_SYS_ADMIN)) { 2332 /* A different attribute in the security namespace. 2333 Restrict to administrator. */ 2334 return -EPERM; 2335 } 2336 2337 /* Not an attribute we recognize, so just check the 2338 ordinary setattr permission. Might want a separate 2339 permission for removexattr. */ 2340 return dentry_has_perm(current, NULL, dentry, FILE__SETATTR); 2341 } 2342 2343 /* No one is allowed to remove a SELinux security label. 2344 You can change the label, but all data must be labeled. */ 2345 return -EACCES; 2346 } 2347 2348 static const char *selinux_inode_xattr_getsuffix(void) 2349 { 2350 return XATTR_SELINUX_SUFFIX; 2351 } 2352 2353 /* 2354 * Copy the in-core inode security context value to the user. If the 2355 * getxattr() prior to this succeeded, check to see if we need to 2356 * canonicalize the value to be finally returned to the user. 2357 * 2358 * Permission check is handled by selinux_inode_getxattr hook. 2359 */ 2360 static int selinux_inode_getsecurity(const struct inode *inode, const char *name, void *buffer, size_t size, int err) 2361 { 2362 struct inode_security_struct *isec = inode->i_security; 2363 2364 if (strcmp(name, XATTR_SELINUX_SUFFIX)) 2365 return -EOPNOTSUPP; 2366 2367 return selinux_getsecurity(isec->sid, buffer, size); 2368 } 2369 2370 static int selinux_inode_setsecurity(struct inode *inode, const char *name, 2371 const void *value, size_t size, int flags) 2372 { 2373 struct inode_security_struct *isec = inode->i_security; 2374 u32 newsid; 2375 int rc; 2376 2377 if (strcmp(name, XATTR_SELINUX_SUFFIX)) 2378 return -EOPNOTSUPP; 2379 2380 if (!value || !size) 2381 return -EACCES; 2382 2383 rc = security_context_to_sid((void*)value, size, &newsid); 2384 if (rc) 2385 return rc; 2386 2387 isec->sid = newsid; 2388 return 0; 2389 } 2390 2391 static int selinux_inode_listsecurity(struct inode *inode, char *buffer, size_t buffer_size) 2392 { 2393 const int len = sizeof(XATTR_NAME_SELINUX); 2394 if (buffer && len <= buffer_size) 2395 memcpy(buffer, XATTR_NAME_SELINUX, len); 2396 return len; 2397 } 2398 2399 /* file security operations */ 2400 2401 static int selinux_file_permission(struct file *file, int mask) 2402 { 2403 int rc; 2404 struct inode *inode = file->f_dentry->d_inode; 2405 2406 if (!mask) { 2407 /* No permission to check. Existence test. */ 2408 return 0; 2409 } 2410 2411 /* file_mask_to_av won't add FILE__WRITE if MAY_APPEND is set */ 2412 if ((file->f_flags & O_APPEND) && (mask & MAY_WRITE)) 2413 mask |= MAY_APPEND; 2414 2415 rc = file_has_perm(current, file, 2416 file_mask_to_av(inode->i_mode, mask)); 2417 if (rc) 2418 return rc; 2419 2420 return selinux_netlbl_inode_permission(inode, mask); 2421 } 2422 2423 static int selinux_file_alloc_security(struct file *file) 2424 { 2425 return file_alloc_security(file); 2426 } 2427 2428 static void selinux_file_free_security(struct file *file) 2429 { 2430 file_free_security(file); 2431 } 2432 2433 static int selinux_file_ioctl(struct file *file, unsigned int cmd, 2434 unsigned long arg) 2435 { 2436 int error = 0; 2437 2438 switch (cmd) { 2439 case FIONREAD: 2440 /* fall through */ 2441 case FIBMAP: 2442 /* fall through */ 2443 case FIGETBSZ: 2444 /* fall through */ 2445 case EXT2_IOC_GETFLAGS: 2446 /* fall through */ 2447 case EXT2_IOC_GETVERSION: 2448 error = file_has_perm(current, file, FILE__GETATTR); 2449 break; 2450 2451 case EXT2_IOC_SETFLAGS: 2452 /* fall through */ 2453 case EXT2_IOC_SETVERSION: 2454 error = file_has_perm(current, file, FILE__SETATTR); 2455 break; 2456 2457 /* sys_ioctl() checks */ 2458 case FIONBIO: 2459 /* fall through */ 2460 case FIOASYNC: 2461 error = file_has_perm(current, file, 0); 2462 break; 2463 2464 case KDSKBENT: 2465 case KDSKBSENT: 2466 error = task_has_capability(current,CAP_SYS_TTY_CONFIG); 2467 break; 2468 2469 /* default case assumes that the command will go 2470 * to the file's ioctl() function. 2471 */ 2472 default: 2473 error = file_has_perm(current, file, FILE__IOCTL); 2474 2475 } 2476 return error; 2477 } 2478 2479 static int file_map_prot_check(struct file *file, unsigned long prot, int shared) 2480 { 2481 #ifndef CONFIG_PPC32 2482 if ((prot & PROT_EXEC) && (!file || (!shared && (prot & PROT_WRITE)))) { 2483 /* 2484 * We are making executable an anonymous mapping or a 2485 * private file mapping that will also be writable. 2486 * This has an additional check. 2487 */ 2488 int rc = task_has_perm(current, current, PROCESS__EXECMEM); 2489 if (rc) 2490 return rc; 2491 } 2492 #endif 2493 2494 if (file) { 2495 /* read access is always possible with a mapping */ 2496 u32 av = FILE__READ; 2497 2498 /* write access only matters if the mapping is shared */ 2499 if (shared && (prot & PROT_WRITE)) 2500 av |= FILE__WRITE; 2501 2502 if (prot & PROT_EXEC) 2503 av |= FILE__EXECUTE; 2504 2505 return file_has_perm(current, file, av); 2506 } 2507 return 0; 2508 } 2509 2510 static int selinux_file_mmap(struct file *file, unsigned long reqprot, 2511 unsigned long prot, unsigned long flags) 2512 { 2513 int rc; 2514 2515 rc = secondary_ops->file_mmap(file, reqprot, prot, flags); 2516 if (rc) 2517 return rc; 2518 2519 if (selinux_checkreqprot) 2520 prot = reqprot; 2521 2522 return file_map_prot_check(file, prot, 2523 (flags & MAP_TYPE) == MAP_SHARED); 2524 } 2525 2526 static int selinux_file_mprotect(struct vm_area_struct *vma, 2527 unsigned long reqprot, 2528 unsigned long prot) 2529 { 2530 int rc; 2531 2532 rc = secondary_ops->file_mprotect(vma, reqprot, prot); 2533 if (rc) 2534 return rc; 2535 2536 if (selinux_checkreqprot) 2537 prot = reqprot; 2538 2539 #ifndef CONFIG_PPC32 2540 if ((prot & PROT_EXEC) && !(vma->vm_flags & VM_EXEC)) { 2541 rc = 0; 2542 if (vma->vm_start >= vma->vm_mm->start_brk && 2543 vma->vm_end <= vma->vm_mm->brk) { 2544 rc = task_has_perm(current, current, 2545 PROCESS__EXECHEAP); 2546 } else if (!vma->vm_file && 2547 vma->vm_start <= vma->vm_mm->start_stack && 2548 vma->vm_end >= vma->vm_mm->start_stack) { 2549 rc = task_has_perm(current, current, PROCESS__EXECSTACK); 2550 } else if (vma->vm_file && vma->anon_vma) { 2551 /* 2552 * We are making executable a file mapping that has 2553 * had some COW done. Since pages might have been 2554 * written, check ability to execute the possibly 2555 * modified content. This typically should only 2556 * occur for text relocations. 2557 */ 2558 rc = file_has_perm(current, vma->vm_file, 2559 FILE__EXECMOD); 2560 } 2561 if (rc) 2562 return rc; 2563 } 2564 #endif 2565 2566 return file_map_prot_check(vma->vm_file, prot, vma->vm_flags&VM_SHARED); 2567 } 2568 2569 static int selinux_file_lock(struct file *file, unsigned int cmd) 2570 { 2571 return file_has_perm(current, file, FILE__LOCK); 2572 } 2573 2574 static int selinux_file_fcntl(struct file *file, unsigned int cmd, 2575 unsigned long arg) 2576 { 2577 int err = 0; 2578 2579 switch (cmd) { 2580 case F_SETFL: 2581 if (!file->f_dentry || !file->f_dentry->d_inode) { 2582 err = -EINVAL; 2583 break; 2584 } 2585 2586 if ((file->f_flags & O_APPEND) && !(arg & O_APPEND)) { 2587 err = file_has_perm(current, file,FILE__WRITE); 2588 break; 2589 } 2590 /* fall through */ 2591 case F_SETOWN: 2592 case F_SETSIG: 2593 case F_GETFL: 2594 case F_GETOWN: 2595 case F_GETSIG: 2596 /* Just check FD__USE permission */ 2597 err = file_has_perm(current, file, 0); 2598 break; 2599 case F_GETLK: 2600 case F_SETLK: 2601 case F_SETLKW: 2602 #if BITS_PER_LONG == 32 2603 case F_GETLK64: 2604 case F_SETLK64: 2605 case F_SETLKW64: 2606 #endif 2607 if (!file->f_dentry || !file->f_dentry->d_inode) { 2608 err = -EINVAL; 2609 break; 2610 } 2611 err = file_has_perm(current, file, FILE__LOCK); 2612 break; 2613 } 2614 2615 return err; 2616 } 2617 2618 static int selinux_file_set_fowner(struct file *file) 2619 { 2620 struct task_security_struct *tsec; 2621 struct file_security_struct *fsec; 2622 2623 tsec = current->security; 2624 fsec = file->f_security; 2625 fsec->fown_sid = tsec->sid; 2626 2627 return 0; 2628 } 2629 2630 static int selinux_file_send_sigiotask(struct task_struct *tsk, 2631 struct fown_struct *fown, int signum) 2632 { 2633 struct file *file; 2634 u32 perm; 2635 struct task_security_struct *tsec; 2636 struct file_security_struct *fsec; 2637 2638 /* struct fown_struct is never outside the context of a struct file */ 2639 file = (struct file *)((long)fown - offsetof(struct file,f_owner)); 2640 2641 tsec = tsk->security; 2642 fsec = file->f_security; 2643 2644 if (!signum) 2645 perm = signal_to_av(SIGIO); /* as per send_sigio_to_task */ 2646 else 2647 perm = signal_to_av(signum); 2648 2649 return avc_has_perm(fsec->fown_sid, tsec->sid, 2650 SECCLASS_PROCESS, perm, NULL); 2651 } 2652 2653 static int selinux_file_receive(struct file *file) 2654 { 2655 return file_has_perm(current, file, file_to_av(file)); 2656 } 2657 2658 /* task security operations */ 2659 2660 static int selinux_task_create(unsigned long clone_flags) 2661 { 2662 int rc; 2663 2664 rc = secondary_ops->task_create(clone_flags); 2665 if (rc) 2666 return rc; 2667 2668 return task_has_perm(current, current, PROCESS__FORK); 2669 } 2670 2671 static int selinux_task_alloc_security(struct task_struct *tsk) 2672 { 2673 struct task_security_struct *tsec1, *tsec2; 2674 int rc; 2675 2676 tsec1 = current->security; 2677 2678 rc = task_alloc_security(tsk); 2679 if (rc) 2680 return rc; 2681 tsec2 = tsk->security; 2682 2683 tsec2->osid = tsec1->osid; 2684 tsec2->sid = tsec1->sid; 2685 2686 /* Retain the exec, fs, key, and sock SIDs across fork */ 2687 tsec2->exec_sid = tsec1->exec_sid; 2688 tsec2->create_sid = tsec1->create_sid; 2689 tsec2->keycreate_sid = tsec1->keycreate_sid; 2690 tsec2->sockcreate_sid = tsec1->sockcreate_sid; 2691 2692 /* Retain ptracer SID across fork, if any. 2693 This will be reset by the ptrace hook upon any 2694 subsequent ptrace_attach operations. */ 2695 tsec2->ptrace_sid = tsec1->ptrace_sid; 2696 2697 return 0; 2698 } 2699 2700 static void selinux_task_free_security(struct task_struct *tsk) 2701 { 2702 task_free_security(tsk); 2703 } 2704 2705 static int selinux_task_setuid(uid_t id0, uid_t id1, uid_t id2, int flags) 2706 { 2707 /* Since setuid only affects the current process, and 2708 since the SELinux controls are not based on the Linux 2709 identity attributes, SELinux does not need to control 2710 this operation. However, SELinux does control the use 2711 of the CAP_SETUID and CAP_SETGID capabilities using the 2712 capable hook. */ 2713 return 0; 2714 } 2715 2716 static int selinux_task_post_setuid(uid_t id0, uid_t id1, uid_t id2, int flags) 2717 { 2718 return secondary_ops->task_post_setuid(id0,id1,id2,flags); 2719 } 2720 2721 static int selinux_task_setgid(gid_t id0, gid_t id1, gid_t id2, int flags) 2722 { 2723 /* See the comment for setuid above. */ 2724 return 0; 2725 } 2726 2727 static int selinux_task_setpgid(struct task_struct *p, pid_t pgid) 2728 { 2729 return task_has_perm(current, p, PROCESS__SETPGID); 2730 } 2731 2732 static int selinux_task_getpgid(struct task_struct *p) 2733 { 2734 return task_has_perm(current, p, PROCESS__GETPGID); 2735 } 2736 2737 static int selinux_task_getsid(struct task_struct *p) 2738 { 2739 return task_has_perm(current, p, PROCESS__GETSESSION); 2740 } 2741 2742 static void selinux_task_getsecid(struct task_struct *p, u32 *secid) 2743 { 2744 selinux_get_task_sid(p, secid); 2745 } 2746 2747 static int selinux_task_setgroups(struct group_info *group_info) 2748 { 2749 /* See the comment for setuid above. */ 2750 return 0; 2751 } 2752 2753 static int selinux_task_setnice(struct task_struct *p, int nice) 2754 { 2755 int rc; 2756 2757 rc = secondary_ops->task_setnice(p, nice); 2758 if (rc) 2759 return rc; 2760 2761 return task_has_perm(current,p, PROCESS__SETSCHED); 2762 } 2763 2764 static int selinux_task_setioprio(struct task_struct *p, int ioprio) 2765 { 2766 return task_has_perm(current, p, PROCESS__SETSCHED); 2767 } 2768 2769 static int selinux_task_getioprio(struct task_struct *p) 2770 { 2771 return task_has_perm(current, p, PROCESS__GETSCHED); 2772 } 2773 2774 static int selinux_task_setrlimit(unsigned int resource, struct rlimit *new_rlim) 2775 { 2776 struct rlimit *old_rlim = current->signal->rlim + resource; 2777 int rc; 2778 2779 rc = secondary_ops->task_setrlimit(resource, new_rlim); 2780 if (rc) 2781 return rc; 2782 2783 /* Control the ability to change the hard limit (whether 2784 lowering or raising it), so that the hard limit can 2785 later be used as a safe reset point for the soft limit 2786 upon context transitions. See selinux_bprm_apply_creds. */ 2787 if (old_rlim->rlim_max != new_rlim->rlim_max) 2788 return task_has_perm(current, current, PROCESS__SETRLIMIT); 2789 2790 return 0; 2791 } 2792 2793 static int selinux_task_setscheduler(struct task_struct *p, int policy, struct sched_param *lp) 2794 { 2795 return task_has_perm(current, p, PROCESS__SETSCHED); 2796 } 2797 2798 static int selinux_task_getscheduler(struct task_struct *p) 2799 { 2800 return task_has_perm(current, p, PROCESS__GETSCHED); 2801 } 2802 2803 static int selinux_task_movememory(struct task_struct *p) 2804 { 2805 return task_has_perm(current, p, PROCESS__SETSCHED); 2806 } 2807 2808 static int selinux_task_kill(struct task_struct *p, struct siginfo *info, 2809 int sig, u32 secid) 2810 { 2811 u32 perm; 2812 int rc; 2813 struct task_security_struct *tsec; 2814 2815 rc = secondary_ops->task_kill(p, info, sig, secid); 2816 if (rc) 2817 return rc; 2818 2819 if (info != SEND_SIG_NOINFO && (is_si_special(info) || SI_FROMKERNEL(info))) 2820 return 0; 2821 2822 if (!sig) 2823 perm = PROCESS__SIGNULL; /* null signal; existence test */ 2824 else 2825 perm = signal_to_av(sig); 2826 tsec = p->security; 2827 if (secid) 2828 rc = avc_has_perm(secid, tsec->sid, SECCLASS_PROCESS, perm, NULL); 2829 else 2830 rc = task_has_perm(current, p, perm); 2831 return rc; 2832 } 2833 2834 static int selinux_task_prctl(int option, 2835 unsigned long arg2, 2836 unsigned long arg3, 2837 unsigned long arg4, 2838 unsigned long arg5) 2839 { 2840 /* The current prctl operations do not appear to require 2841 any SELinux controls since they merely observe or modify 2842 the state of the current process. */ 2843 return 0; 2844 } 2845 2846 static int selinux_task_wait(struct task_struct *p) 2847 { 2848 u32 perm; 2849 2850 perm = signal_to_av(p->exit_signal); 2851 2852 return task_has_perm(p, current, perm); 2853 } 2854 2855 static void selinux_task_reparent_to_init(struct task_struct *p) 2856 { 2857 struct task_security_struct *tsec; 2858 2859 secondary_ops->task_reparent_to_init(p); 2860 2861 tsec = p->security; 2862 tsec->osid = tsec->sid; 2863 tsec->sid = SECINITSID_KERNEL; 2864 return; 2865 } 2866 2867 static void selinux_task_to_inode(struct task_struct *p, 2868 struct inode *inode) 2869 { 2870 struct task_security_struct *tsec = p->security; 2871 struct inode_security_struct *isec = inode->i_security; 2872 2873 isec->sid = tsec->sid; 2874 isec->initialized = 1; 2875 return; 2876 } 2877 2878 /* Returns error only if unable to parse addresses */ 2879 static int selinux_parse_skb_ipv4(struct sk_buff *skb, struct avc_audit_data *ad) 2880 { 2881 int offset, ihlen, ret = -EINVAL; 2882 struct iphdr _iph, *ih; 2883 2884 offset = skb->nh.raw - skb->data; 2885 ih = skb_header_pointer(skb, offset, sizeof(_iph), &_iph); 2886 if (ih == NULL) 2887 goto out; 2888 2889 ihlen = ih->ihl * 4; 2890 if (ihlen < sizeof(_iph)) 2891 goto out; 2892 2893 ad->u.net.v4info.saddr = ih->saddr; 2894 ad->u.net.v4info.daddr = ih->daddr; 2895 ret = 0; 2896 2897 switch (ih->protocol) { 2898 case IPPROTO_TCP: { 2899 struct tcphdr _tcph, *th; 2900 2901 if (ntohs(ih->frag_off) & IP_OFFSET) 2902 break; 2903 2904 offset += ihlen; 2905 th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph); 2906 if (th == NULL) 2907 break; 2908 2909 ad->u.net.sport = th->source; 2910 ad->u.net.dport = th->dest; 2911 break; 2912 } 2913 2914 case IPPROTO_UDP: { 2915 struct udphdr _udph, *uh; 2916 2917 if (ntohs(ih->frag_off) & IP_OFFSET) 2918 break; 2919 2920 offset += ihlen; 2921 uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph); 2922 if (uh == NULL) 2923 break; 2924 2925 ad->u.net.sport = uh->source; 2926 ad->u.net.dport = uh->dest; 2927 break; 2928 } 2929 2930 default: 2931 break; 2932 } 2933 out: 2934 return ret; 2935 } 2936 2937 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE) 2938 2939 /* Returns error only if unable to parse addresses */ 2940 static int selinux_parse_skb_ipv6(struct sk_buff *skb, struct avc_audit_data *ad) 2941 { 2942 u8 nexthdr; 2943 int ret = -EINVAL, offset; 2944 struct ipv6hdr _ipv6h, *ip6; 2945 2946 offset = skb->nh.raw - skb->data; 2947 ip6 = skb_header_pointer(skb, offset, sizeof(_ipv6h), &_ipv6h); 2948 if (ip6 == NULL) 2949 goto out; 2950 2951 ipv6_addr_copy(&ad->u.net.v6info.saddr, &ip6->saddr); 2952 ipv6_addr_copy(&ad->u.net.v6info.daddr, &ip6->daddr); 2953 ret = 0; 2954 2955 nexthdr = ip6->nexthdr; 2956 offset += sizeof(_ipv6h); 2957 offset = ipv6_skip_exthdr(skb, offset, &nexthdr); 2958 if (offset < 0) 2959 goto out; 2960 2961 switch (nexthdr) { 2962 case IPPROTO_TCP: { 2963 struct tcphdr _tcph, *th; 2964 2965 th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph); 2966 if (th == NULL) 2967 break; 2968 2969 ad->u.net.sport = th->source; 2970 ad->u.net.dport = th->dest; 2971 break; 2972 } 2973 2974 case IPPROTO_UDP: { 2975 struct udphdr _udph, *uh; 2976 2977 uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph); 2978 if (uh == NULL) 2979 break; 2980 2981 ad->u.net.sport = uh->source; 2982 ad->u.net.dport = uh->dest; 2983 break; 2984 } 2985 2986 /* includes fragments */ 2987 default: 2988 break; 2989 } 2990 out: 2991 return ret; 2992 } 2993 2994 #endif /* IPV6 */ 2995 2996 static int selinux_parse_skb(struct sk_buff *skb, struct avc_audit_data *ad, 2997 char **addrp, int *len, int src) 2998 { 2999 int ret = 0; 3000 3001 switch (ad->u.net.family) { 3002 case PF_INET: 3003 ret = selinux_parse_skb_ipv4(skb, ad); 3004 if (ret || !addrp) 3005 break; 3006 *len = 4; 3007 *addrp = (char *)(src ? &ad->u.net.v4info.saddr : 3008 &ad->u.net.v4info.daddr); 3009 break; 3010 3011 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE) 3012 case PF_INET6: 3013 ret = selinux_parse_skb_ipv6(skb, ad); 3014 if (ret || !addrp) 3015 break; 3016 *len = 16; 3017 *addrp = (char *)(src ? &ad->u.net.v6info.saddr : 3018 &ad->u.net.v6info.daddr); 3019 break; 3020 #endif /* IPV6 */ 3021 default: 3022 break; 3023 } 3024 3025 return ret; 3026 } 3027 3028 /* socket security operations */ 3029 static int socket_has_perm(struct task_struct *task, struct socket *sock, 3030 u32 perms) 3031 { 3032 struct inode_security_struct *isec; 3033 struct task_security_struct *tsec; 3034 struct avc_audit_data ad; 3035 int err = 0; 3036 3037 tsec = task->security; 3038 isec = SOCK_INODE(sock)->i_security; 3039 3040 if (isec->sid == SECINITSID_KERNEL) 3041 goto out; 3042 3043 AVC_AUDIT_DATA_INIT(&ad,NET); 3044 ad.u.net.sk = sock->sk; 3045 err = avc_has_perm(tsec->sid, isec->sid, isec->sclass, perms, &ad); 3046 3047 out: 3048 return err; 3049 } 3050 3051 static int selinux_socket_create(int family, int type, 3052 int protocol, int kern) 3053 { 3054 int err = 0; 3055 struct task_security_struct *tsec; 3056 u32 newsid; 3057 3058 if (kern) 3059 goto out; 3060 3061 tsec = current->security; 3062 newsid = tsec->sockcreate_sid ? : tsec->sid; 3063 err = avc_has_perm(tsec->sid, newsid, 3064 socket_type_to_security_class(family, type, 3065 protocol), SOCKET__CREATE, NULL); 3066 3067 out: 3068 return err; 3069 } 3070 3071 static int selinux_socket_post_create(struct socket *sock, int family, 3072 int type, int protocol, int kern) 3073 { 3074 int err = 0; 3075 struct inode_security_struct *isec; 3076 struct task_security_struct *tsec; 3077 struct sk_security_struct *sksec; 3078 u32 newsid; 3079 3080 isec = SOCK_INODE(sock)->i_security; 3081 3082 tsec = current->security; 3083 newsid = tsec->sockcreate_sid ? : tsec->sid; 3084 isec->sclass = socket_type_to_security_class(family, type, protocol); 3085 isec->sid = kern ? SECINITSID_KERNEL : newsid; 3086 isec->initialized = 1; 3087 3088 if (sock->sk) { 3089 sksec = sock->sk->sk_security; 3090 sksec->sid = isec->sid; 3091 err = selinux_netlbl_socket_post_create(sock, 3092 family, 3093 isec->sid); 3094 } 3095 3096 return err; 3097 } 3098 3099 /* Range of port numbers used to automatically bind. 3100 Need to determine whether we should perform a name_bind 3101 permission check between the socket and the port number. */ 3102 #define ip_local_port_range_0 sysctl_local_port_range[0] 3103 #define ip_local_port_range_1 sysctl_local_port_range[1] 3104 3105 static int selinux_socket_bind(struct socket *sock, struct sockaddr *address, int addrlen) 3106 { 3107 u16 family; 3108 int err; 3109 3110 err = socket_has_perm(current, sock, SOCKET__BIND); 3111 if (err) 3112 goto out; 3113 3114 /* 3115 * If PF_INET or PF_INET6, check name_bind permission for the port. 3116 * Multiple address binding for SCTP is not supported yet: we just 3117 * check the first address now. 3118 */ 3119 family = sock->sk->sk_family; 3120 if (family == PF_INET || family == PF_INET6) { 3121 char *addrp; 3122 struct inode_security_struct *isec; 3123 struct task_security_struct *tsec; 3124 struct avc_audit_data ad; 3125 struct sockaddr_in *addr4 = NULL; 3126 struct sockaddr_in6 *addr6 = NULL; 3127 unsigned short snum; 3128 struct sock *sk = sock->sk; 3129 u32 sid, node_perm, addrlen; 3130 3131 tsec = current->security; 3132 isec = SOCK_INODE(sock)->i_security; 3133 3134 if (family == PF_INET) { 3135 addr4 = (struct sockaddr_in *)address; 3136 snum = ntohs(addr4->sin_port); 3137 addrlen = sizeof(addr4->sin_addr.s_addr); 3138 addrp = (char *)&addr4->sin_addr.s_addr; 3139 } else { 3140 addr6 = (struct sockaddr_in6 *)address; 3141 snum = ntohs(addr6->sin6_port); 3142 addrlen = sizeof(addr6->sin6_addr.s6_addr); 3143 addrp = (char *)&addr6->sin6_addr.s6_addr; 3144 } 3145 3146 if (snum&&(snum < max(PROT_SOCK,ip_local_port_range_0) || 3147 snum > ip_local_port_range_1)) { 3148 err = security_port_sid(sk->sk_family, sk->sk_type, 3149 sk->sk_protocol, snum, &sid); 3150 if (err) 3151 goto out; 3152 AVC_AUDIT_DATA_INIT(&ad,NET); 3153 ad.u.net.sport = htons(snum); 3154 ad.u.net.family = family; 3155 err = avc_has_perm(isec->sid, sid, 3156 isec->sclass, 3157 SOCKET__NAME_BIND, &ad); 3158 if (err) 3159 goto out; 3160 } 3161 3162 switch(isec->sclass) { 3163 case SECCLASS_TCP_SOCKET: 3164 node_perm = TCP_SOCKET__NODE_BIND; 3165 break; 3166 3167 case SECCLASS_UDP_SOCKET: 3168 node_perm = UDP_SOCKET__NODE_BIND; 3169 break; 3170 3171 default: 3172 node_perm = RAWIP_SOCKET__NODE_BIND; 3173 break; 3174 } 3175 3176 err = security_node_sid(family, addrp, addrlen, &sid); 3177 if (err) 3178 goto out; 3179 3180 AVC_AUDIT_DATA_INIT(&ad,NET); 3181 ad.u.net.sport = htons(snum); 3182 ad.u.net.family = family; 3183 3184 if (family == PF_INET) 3185 ad.u.net.v4info.saddr = addr4->sin_addr.s_addr; 3186 else 3187 ipv6_addr_copy(&ad.u.net.v6info.saddr, &addr6->sin6_addr); 3188 3189 err = avc_has_perm(isec->sid, sid, 3190 isec->sclass, node_perm, &ad); 3191 if (err) 3192 goto out; 3193 } 3194 out: 3195 return err; 3196 } 3197 3198 static int selinux_socket_connect(struct socket *sock, struct sockaddr *address, int addrlen) 3199 { 3200 struct inode_security_struct *isec; 3201 int err; 3202 3203 err = socket_has_perm(current, sock, SOCKET__CONNECT); 3204 if (err) 3205 return err; 3206 3207 /* 3208 * If a TCP socket, check name_connect permission for the port. 3209 */ 3210 isec = SOCK_INODE(sock)->i_security; 3211 if (isec->sclass == SECCLASS_TCP_SOCKET) { 3212 struct sock *sk = sock->sk; 3213 struct avc_audit_data ad; 3214 struct sockaddr_in *addr4 = NULL; 3215 struct sockaddr_in6 *addr6 = NULL; 3216 unsigned short snum; 3217 u32 sid; 3218 3219 if (sk->sk_family == PF_INET) { 3220 addr4 = (struct sockaddr_in *)address; 3221 if (addrlen < sizeof(struct sockaddr_in)) 3222 return -EINVAL; 3223 snum = ntohs(addr4->sin_port); 3224 } else { 3225 addr6 = (struct sockaddr_in6 *)address; 3226 if (addrlen < SIN6_LEN_RFC2133) 3227 return -EINVAL; 3228 snum = ntohs(addr6->sin6_port); 3229 } 3230 3231 err = security_port_sid(sk->sk_family, sk->sk_type, 3232 sk->sk_protocol, snum, &sid); 3233 if (err) 3234 goto out; 3235 3236 AVC_AUDIT_DATA_INIT(&ad,NET); 3237 ad.u.net.dport = htons(snum); 3238 ad.u.net.family = sk->sk_family; 3239 err = avc_has_perm(isec->sid, sid, isec->sclass, 3240 TCP_SOCKET__NAME_CONNECT, &ad); 3241 if (err) 3242 goto out; 3243 } 3244 3245 out: 3246 return err; 3247 } 3248 3249 static int selinux_socket_listen(struct socket *sock, int backlog) 3250 { 3251 return socket_has_perm(current, sock, SOCKET__LISTEN); 3252 } 3253 3254 static int selinux_socket_accept(struct socket *sock, struct socket *newsock) 3255 { 3256 int err; 3257 struct inode_security_struct *isec; 3258 struct inode_security_struct *newisec; 3259 3260 err = socket_has_perm(current, sock, SOCKET__ACCEPT); 3261 if (err) 3262 return err; 3263 3264 newisec = SOCK_INODE(newsock)->i_security; 3265 3266 isec = SOCK_INODE(sock)->i_security; 3267 newisec->sclass = isec->sclass; 3268 newisec->sid = isec->sid; 3269 newisec->initialized = 1; 3270 3271 return 0; 3272 } 3273 3274 static int selinux_socket_sendmsg(struct socket *sock, struct msghdr *msg, 3275 int size) 3276 { 3277 int rc; 3278 3279 rc = socket_has_perm(current, sock, SOCKET__WRITE); 3280 if (rc) 3281 return rc; 3282 3283 return selinux_netlbl_inode_permission(SOCK_INODE(sock), MAY_WRITE); 3284 } 3285 3286 static int selinux_socket_recvmsg(struct socket *sock, struct msghdr *msg, 3287 int size, int flags) 3288 { 3289 return socket_has_perm(current, sock, SOCKET__READ); 3290 } 3291 3292 static int selinux_socket_getsockname(struct socket *sock) 3293 { 3294 return socket_has_perm(current, sock, SOCKET__GETATTR); 3295 } 3296 3297 static int selinux_socket_getpeername(struct socket *sock) 3298 { 3299 return socket_has_perm(current, sock, SOCKET__GETATTR); 3300 } 3301 3302 static int selinux_socket_setsockopt(struct socket *sock,int level,int optname) 3303 { 3304 return socket_has_perm(current, sock, SOCKET__SETOPT); 3305 } 3306 3307 static int selinux_socket_getsockopt(struct socket *sock, int level, 3308 int optname) 3309 { 3310 return socket_has_perm(current, sock, SOCKET__GETOPT); 3311 } 3312 3313 static int selinux_socket_shutdown(struct socket *sock, int how) 3314 { 3315 return socket_has_perm(current, sock, SOCKET__SHUTDOWN); 3316 } 3317 3318 static int selinux_socket_unix_stream_connect(struct socket *sock, 3319 struct socket *other, 3320 struct sock *newsk) 3321 { 3322 struct sk_security_struct *ssec; 3323 struct inode_security_struct *isec; 3324 struct inode_security_struct *other_isec; 3325 struct avc_audit_data ad; 3326 int err; 3327 3328 err = secondary_ops->unix_stream_connect(sock, other, newsk); 3329 if (err) 3330 return err; 3331 3332 isec = SOCK_INODE(sock)->i_security; 3333 other_isec = SOCK_INODE(other)->i_security; 3334 3335 AVC_AUDIT_DATA_INIT(&ad,NET); 3336 ad.u.net.sk = other->sk; 3337 3338 err = avc_has_perm(isec->sid, other_isec->sid, 3339 isec->sclass, 3340 UNIX_STREAM_SOCKET__CONNECTTO, &ad); 3341 if (err) 3342 return err; 3343 3344 /* connecting socket */ 3345 ssec = sock->sk->sk_security; 3346 ssec->peer_sid = other_isec->sid; 3347 3348 /* server child socket */ 3349 ssec = newsk->sk_security; 3350 ssec->peer_sid = isec->sid; 3351 err = security_sid_mls_copy(other_isec->sid, ssec->peer_sid, &ssec->sid); 3352 3353 return err; 3354 } 3355 3356 static int selinux_socket_unix_may_send(struct socket *sock, 3357 struct socket *other) 3358 { 3359 struct inode_security_struct *isec; 3360 struct inode_security_struct *other_isec; 3361 struct avc_audit_data ad; 3362 int err; 3363 3364 isec = SOCK_INODE(sock)->i_security; 3365 other_isec = SOCK_INODE(other)->i_security; 3366 3367 AVC_AUDIT_DATA_INIT(&ad,NET); 3368 ad.u.net.sk = other->sk; 3369 3370 err = avc_has_perm(isec->sid, other_isec->sid, 3371 isec->sclass, SOCKET__SENDTO, &ad); 3372 if (err) 3373 return err; 3374 3375 return 0; 3376 } 3377 3378 static int selinux_sock_rcv_skb_compat(struct sock *sk, struct sk_buff *skb, 3379 struct avc_audit_data *ad, u16 family, char *addrp, int len) 3380 { 3381 int err = 0; 3382 u32 netif_perm, node_perm, node_sid, if_sid, recv_perm = 0; 3383 struct socket *sock; 3384 u16 sock_class = 0; 3385 u32 sock_sid = 0; 3386 3387 read_lock_bh(&sk->sk_callback_lock); 3388 sock = sk->sk_socket; 3389 if (sock) { 3390 struct inode *inode; 3391 inode = SOCK_INODE(sock); 3392 if (inode) { 3393 struct inode_security_struct *isec; 3394 isec = inode->i_security; 3395 sock_sid = isec->sid; 3396 sock_class = isec->sclass; 3397 } 3398 } 3399 read_unlock_bh(&sk->sk_callback_lock); 3400 if (!sock_sid) 3401 goto out; 3402 3403 if (!skb->dev) 3404 goto out; 3405 3406 err = sel_netif_sids(skb->dev, &if_sid, NULL); 3407 if (err) 3408 goto out; 3409 3410 switch (sock_class) { 3411 case SECCLASS_UDP_SOCKET: 3412 netif_perm = NETIF__UDP_RECV; 3413 node_perm = NODE__UDP_RECV; 3414 recv_perm = UDP_SOCKET__RECV_MSG; 3415 break; 3416 3417 case SECCLASS_TCP_SOCKET: 3418 netif_perm = NETIF__TCP_RECV; 3419 node_perm = NODE__TCP_RECV; 3420 recv_perm = TCP_SOCKET__RECV_MSG; 3421 break; 3422 3423 default: 3424 netif_perm = NETIF__RAWIP_RECV; 3425 node_perm = NODE__RAWIP_RECV; 3426 break; 3427 } 3428 3429 err = avc_has_perm(sock_sid, if_sid, SECCLASS_NETIF, netif_perm, ad); 3430 if (err) 3431 goto out; 3432 3433 err = security_node_sid(family, addrp, len, &node_sid); 3434 if (err) 3435 goto out; 3436 3437 err = avc_has_perm(sock_sid, node_sid, SECCLASS_NODE, node_perm, ad); 3438 if (err) 3439 goto out; 3440 3441 if (recv_perm) { 3442 u32 port_sid; 3443 3444 err = security_port_sid(sk->sk_family, sk->sk_type, 3445 sk->sk_protocol, ntohs(ad->u.net.sport), 3446 &port_sid); 3447 if (err) 3448 goto out; 3449 3450 err = avc_has_perm(sock_sid, port_sid, 3451 sock_class, recv_perm, ad); 3452 } 3453 3454 out: 3455 return err; 3456 } 3457 3458 static int selinux_socket_sock_rcv_skb(struct sock *sk, struct sk_buff *skb) 3459 { 3460 u16 family; 3461 char *addrp; 3462 int len, err = 0; 3463 struct avc_audit_data ad; 3464 struct sk_security_struct *sksec = sk->sk_security; 3465 3466 family = sk->sk_family; 3467 if (family != PF_INET && family != PF_INET6) 3468 goto out; 3469 3470 /* Handle mapped IPv4 packets arriving via IPv6 sockets */ 3471 if (family == PF_INET6 && skb->protocol == ntohs(ETH_P_IP)) 3472 family = PF_INET; 3473 3474 AVC_AUDIT_DATA_INIT(&ad, NET); 3475 ad.u.net.netif = skb->dev ? skb->dev->name : "[unknown]"; 3476 ad.u.net.family = family; 3477 3478 err = selinux_parse_skb(skb, &ad, &addrp, &len, 1); 3479 if (err) 3480 goto out; 3481 3482 if (selinux_compat_net) 3483 err = selinux_sock_rcv_skb_compat(sk, skb, &ad, family, 3484 addrp, len); 3485 else 3486 err = avc_has_perm(sksec->sid, skb->secmark, SECCLASS_PACKET, 3487 PACKET__RECV, &ad); 3488 if (err) 3489 goto out; 3490 3491 err = selinux_netlbl_sock_rcv_skb(sksec, skb, &ad); 3492 if (err) 3493 goto out; 3494 3495 err = selinux_xfrm_sock_rcv_skb(sksec->sid, skb, &ad); 3496 out: 3497 return err; 3498 } 3499 3500 static int selinux_socket_getpeersec_stream(struct socket *sock, char __user *optval, 3501 int __user *optlen, unsigned len) 3502 { 3503 int err = 0; 3504 char *scontext; 3505 u32 scontext_len; 3506 struct sk_security_struct *ssec; 3507 struct inode_security_struct *isec; 3508 u32 peer_sid = 0; 3509 3510 isec = SOCK_INODE(sock)->i_security; 3511 3512 /* if UNIX_STREAM check peer_sid, if TCP check dst for labelled sa */ 3513 if (isec->sclass == SECCLASS_UNIX_STREAM_SOCKET) { 3514 ssec = sock->sk->sk_security; 3515 peer_sid = ssec->peer_sid; 3516 } 3517 else if (isec->sclass == SECCLASS_TCP_SOCKET) { 3518 peer_sid = selinux_netlbl_socket_getpeersec_stream(sock); 3519 if (peer_sid == SECSID_NULL) 3520 peer_sid = selinux_socket_getpeer_stream(sock->sk); 3521 if (peer_sid == SECSID_NULL) { 3522 err = -ENOPROTOOPT; 3523 goto out; 3524 } 3525 } 3526 else { 3527 err = -ENOPROTOOPT; 3528 goto out; 3529 } 3530 3531 err = security_sid_to_context(peer_sid, &scontext, &scontext_len); 3532 3533 if (err) 3534 goto out; 3535 3536 if (scontext_len > len) { 3537 err = -ERANGE; 3538 goto out_len; 3539 } 3540 3541 if (copy_to_user(optval, scontext, scontext_len)) 3542 err = -EFAULT; 3543 3544 out_len: 3545 if (put_user(scontext_len, optlen)) 3546 err = -EFAULT; 3547 3548 kfree(scontext); 3549 out: 3550 return err; 3551 } 3552 3553 static int selinux_socket_getpeersec_dgram(struct socket *sock, struct sk_buff *skb, u32 *secid) 3554 { 3555 u32 peer_secid = SECSID_NULL; 3556 int err = 0; 3557 3558 if (sock && (sock->sk->sk_family == PF_UNIX)) 3559 selinux_get_inode_sid(SOCK_INODE(sock), &peer_secid); 3560 else if (skb) { 3561 peer_secid = selinux_netlbl_socket_getpeersec_dgram(skb); 3562 if (peer_secid == SECSID_NULL) 3563 peer_secid = selinux_socket_getpeer_dgram(skb); 3564 } 3565 3566 if (peer_secid == SECSID_NULL) 3567 err = -EINVAL; 3568 *secid = peer_secid; 3569 3570 return err; 3571 } 3572 3573 static int selinux_sk_alloc_security(struct sock *sk, int family, gfp_t priority) 3574 { 3575 return sk_alloc_security(sk, family, priority); 3576 } 3577 3578 static void selinux_sk_free_security(struct sock *sk) 3579 { 3580 sk_free_security(sk); 3581 } 3582 3583 static void selinux_sk_clone_security(const struct sock *sk, struct sock *newsk) 3584 { 3585 struct sk_security_struct *ssec = sk->sk_security; 3586 struct sk_security_struct *newssec = newsk->sk_security; 3587 3588 newssec->sid = ssec->sid; 3589 newssec->peer_sid = ssec->peer_sid; 3590 3591 selinux_netlbl_sk_clone_security(ssec, newssec); 3592 } 3593 3594 static void selinux_sk_getsecid(struct sock *sk, u32 *secid) 3595 { 3596 if (!sk) 3597 *secid = SECINITSID_ANY_SOCKET; 3598 else { 3599 struct sk_security_struct *sksec = sk->sk_security; 3600 3601 *secid = sksec->sid; 3602 } 3603 } 3604 3605 static void selinux_sock_graft(struct sock* sk, struct socket *parent) 3606 { 3607 struct inode_security_struct *isec = SOCK_INODE(parent)->i_security; 3608 struct sk_security_struct *sksec = sk->sk_security; 3609 3610 isec->sid = sksec->sid; 3611 3612 selinux_netlbl_sock_graft(sk, parent); 3613 } 3614 3615 static int selinux_inet_conn_request(struct sock *sk, struct sk_buff *skb, 3616 struct request_sock *req) 3617 { 3618 struct sk_security_struct *sksec = sk->sk_security; 3619 int err; 3620 u32 newsid; 3621 u32 peersid; 3622 3623 newsid = selinux_netlbl_inet_conn_request(skb, sksec->sid); 3624 if (newsid != SECSID_NULL) { 3625 req->secid = newsid; 3626 return 0; 3627 } 3628 3629 err = selinux_xfrm_decode_session(skb, &peersid, 0); 3630 BUG_ON(err); 3631 3632 if (peersid == SECSID_NULL) { 3633 req->secid = sksec->sid; 3634 return 0; 3635 } 3636 3637 err = security_sid_mls_copy(sksec->sid, peersid, &newsid); 3638 if (err) 3639 return err; 3640 3641 req->secid = newsid; 3642 return 0; 3643 } 3644 3645 static void selinux_inet_csk_clone(struct sock *newsk, 3646 const struct request_sock *req) 3647 { 3648 struct sk_security_struct *newsksec = newsk->sk_security; 3649 3650 newsksec->sid = req->secid; 3651 /* NOTE: Ideally, we should also get the isec->sid for the 3652 new socket in sync, but we don't have the isec available yet. 3653 So we will wait until sock_graft to do it, by which 3654 time it will have been created and available. */ 3655 3656 selinux_netlbl_sk_security_init(newsksec, req->rsk_ops->family); 3657 } 3658 3659 static void selinux_req_classify_flow(const struct request_sock *req, 3660 struct flowi *fl) 3661 { 3662 fl->secid = req->secid; 3663 } 3664 3665 static int selinux_nlmsg_perm(struct sock *sk, struct sk_buff *skb) 3666 { 3667 int err = 0; 3668 u32 perm; 3669 struct nlmsghdr *nlh; 3670 struct socket *sock = sk->sk_socket; 3671 struct inode_security_struct *isec = SOCK_INODE(sock)->i_security; 3672 3673 if (skb->len < NLMSG_SPACE(0)) { 3674 err = -EINVAL; 3675 goto out; 3676 } 3677 nlh = (struct nlmsghdr *)skb->data; 3678 3679 err = selinux_nlmsg_lookup(isec->sclass, nlh->nlmsg_type, &perm); 3680 if (err) { 3681 if (err == -EINVAL) { 3682 audit_log(current->audit_context, GFP_KERNEL, AUDIT_SELINUX_ERR, 3683 "SELinux: unrecognized netlink message" 3684 " type=%hu for sclass=%hu\n", 3685 nlh->nlmsg_type, isec->sclass); 3686 if (!selinux_enforcing) 3687 err = 0; 3688 } 3689 3690 /* Ignore */ 3691 if (err == -ENOENT) 3692 err = 0; 3693 goto out; 3694 } 3695 3696 err = socket_has_perm(current, sock, perm); 3697 out: 3698 return err; 3699 } 3700 3701 #ifdef CONFIG_NETFILTER 3702 3703 static int selinux_ip_postroute_last_compat(struct sock *sk, struct net_device *dev, 3704 struct avc_audit_data *ad, 3705 u16 family, char *addrp, int len) 3706 { 3707 int err = 0; 3708 u32 netif_perm, node_perm, node_sid, if_sid, send_perm = 0; 3709 struct socket *sock; 3710 struct inode *inode; 3711 struct inode_security_struct *isec; 3712 3713 sock = sk->sk_socket; 3714 if (!sock) 3715 goto out; 3716 3717 inode = SOCK_INODE(sock); 3718 if (!inode) 3719 goto out; 3720 3721 isec = inode->i_security; 3722 3723 err = sel_netif_sids(dev, &if_sid, NULL); 3724 if (err) 3725 goto out; 3726 3727 switch (isec->sclass) { 3728 case SECCLASS_UDP_SOCKET: 3729 netif_perm = NETIF__UDP_SEND; 3730 node_perm = NODE__UDP_SEND; 3731 send_perm = UDP_SOCKET__SEND_MSG; 3732 break; 3733 3734 case SECCLASS_TCP_SOCKET: 3735 netif_perm = NETIF__TCP_SEND; 3736 node_perm = NODE__TCP_SEND; 3737 send_perm = TCP_SOCKET__SEND_MSG; 3738 break; 3739 3740 default: 3741 netif_perm = NETIF__RAWIP_SEND; 3742 node_perm = NODE__RAWIP_SEND; 3743 break; 3744 } 3745 3746 err = avc_has_perm(isec->sid, if_sid, SECCLASS_NETIF, netif_perm, ad); 3747 if (err) 3748 goto out; 3749 3750 err = security_node_sid(family, addrp, len, &node_sid); 3751 if (err) 3752 goto out; 3753 3754 err = avc_has_perm(isec->sid, node_sid, SECCLASS_NODE, node_perm, ad); 3755 if (err) 3756 goto out; 3757 3758 if (send_perm) { 3759 u32 port_sid; 3760 3761 err = security_port_sid(sk->sk_family, 3762 sk->sk_type, 3763 sk->sk_protocol, 3764 ntohs(ad->u.net.dport), 3765 &port_sid); 3766 if (err) 3767 goto out; 3768 3769 err = avc_has_perm(isec->sid, port_sid, isec->sclass, 3770 send_perm, ad); 3771 } 3772 out: 3773 return err; 3774 } 3775 3776 static unsigned int selinux_ip_postroute_last(unsigned int hooknum, 3777 struct sk_buff **pskb, 3778 const struct net_device *in, 3779 const struct net_device *out, 3780 int (*okfn)(struct sk_buff *), 3781 u16 family) 3782 { 3783 char *addrp; 3784 int len, err = 0; 3785 struct sock *sk; 3786 struct sk_buff *skb = *pskb; 3787 struct avc_audit_data ad; 3788 struct net_device *dev = (struct net_device *)out; 3789 struct sk_security_struct *sksec; 3790 3791 sk = skb->sk; 3792 if (!sk) 3793 goto out; 3794 3795 sksec = sk->sk_security; 3796 3797 AVC_AUDIT_DATA_INIT(&ad, NET); 3798 ad.u.net.netif = dev->name; 3799 ad.u.net.family = family; 3800 3801 err = selinux_parse_skb(skb, &ad, &addrp, &len, 0); 3802 if (err) 3803 goto out; 3804 3805 if (selinux_compat_net) 3806 err = selinux_ip_postroute_last_compat(sk, dev, &ad, 3807 family, addrp, len); 3808 else 3809 err = avc_has_perm(sksec->sid, skb->secmark, SECCLASS_PACKET, 3810 PACKET__SEND, &ad); 3811 3812 if (err) 3813 goto out; 3814 3815 err = selinux_xfrm_postroute_last(sksec->sid, skb, &ad); 3816 out: 3817 return err ? NF_DROP : NF_ACCEPT; 3818 } 3819 3820 static unsigned int selinux_ipv4_postroute_last(unsigned int hooknum, 3821 struct sk_buff **pskb, 3822 const struct net_device *in, 3823 const struct net_device *out, 3824 int (*okfn)(struct sk_buff *)) 3825 { 3826 return selinux_ip_postroute_last(hooknum, pskb, in, out, okfn, PF_INET); 3827 } 3828 3829 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE) 3830 3831 static unsigned int selinux_ipv6_postroute_last(unsigned int hooknum, 3832 struct sk_buff **pskb, 3833 const struct net_device *in, 3834 const struct net_device *out, 3835 int (*okfn)(struct sk_buff *)) 3836 { 3837 return selinux_ip_postroute_last(hooknum, pskb, in, out, okfn, PF_INET6); 3838 } 3839 3840 #endif /* IPV6 */ 3841 3842 #endif /* CONFIG_NETFILTER */ 3843 3844 static int selinux_netlink_send(struct sock *sk, struct sk_buff *skb) 3845 { 3846 int err; 3847 3848 err = secondary_ops->netlink_send(sk, skb); 3849 if (err) 3850 return err; 3851 3852 if (policydb_loaded_version >= POLICYDB_VERSION_NLCLASS) 3853 err = selinux_nlmsg_perm(sk, skb); 3854 3855 return err; 3856 } 3857 3858 static int selinux_netlink_recv(struct sk_buff *skb, int capability) 3859 { 3860 int err; 3861 struct avc_audit_data ad; 3862 3863 err = secondary_ops->netlink_recv(skb, capability); 3864 if (err) 3865 return err; 3866 3867 AVC_AUDIT_DATA_INIT(&ad, CAP); 3868 ad.u.cap = capability; 3869 3870 return avc_has_perm(NETLINK_CB(skb).sid, NETLINK_CB(skb).sid, 3871 SECCLASS_CAPABILITY, CAP_TO_MASK(capability), &ad); 3872 } 3873 3874 static int ipc_alloc_security(struct task_struct *task, 3875 struct kern_ipc_perm *perm, 3876 u16 sclass) 3877 { 3878 struct task_security_struct *tsec = task->security; 3879 struct ipc_security_struct *isec; 3880 3881 isec = kzalloc(sizeof(struct ipc_security_struct), GFP_KERNEL); 3882 if (!isec) 3883 return -ENOMEM; 3884 3885 isec->sclass = sclass; 3886 isec->ipc_perm = perm; 3887 isec->sid = tsec->sid; 3888 perm->security = isec; 3889 3890 return 0; 3891 } 3892 3893 static void ipc_free_security(struct kern_ipc_perm *perm) 3894 { 3895 struct ipc_security_struct *isec = perm->security; 3896 perm->security = NULL; 3897 kfree(isec); 3898 } 3899 3900 static int msg_msg_alloc_security(struct msg_msg *msg) 3901 { 3902 struct msg_security_struct *msec; 3903 3904 msec = kzalloc(sizeof(struct msg_security_struct), GFP_KERNEL); 3905 if (!msec) 3906 return -ENOMEM; 3907 3908 msec->msg = msg; 3909 msec->sid = SECINITSID_UNLABELED; 3910 msg->security = msec; 3911 3912 return 0; 3913 } 3914 3915 static void msg_msg_free_security(struct msg_msg *msg) 3916 { 3917 struct msg_security_struct *msec = msg->security; 3918 3919 msg->security = NULL; 3920 kfree(msec); 3921 } 3922 3923 static int ipc_has_perm(struct kern_ipc_perm *ipc_perms, 3924 u32 perms) 3925 { 3926 struct task_security_struct *tsec; 3927 struct ipc_security_struct *isec; 3928 struct avc_audit_data ad; 3929 3930 tsec = current->security; 3931 isec = ipc_perms->security; 3932 3933 AVC_AUDIT_DATA_INIT(&ad, IPC); 3934 ad.u.ipc_id = ipc_perms->key; 3935 3936 return avc_has_perm(tsec->sid, isec->sid, isec->sclass, perms, &ad); 3937 } 3938 3939 static int selinux_msg_msg_alloc_security(struct msg_msg *msg) 3940 { 3941 return msg_msg_alloc_security(msg); 3942 } 3943 3944 static void selinux_msg_msg_free_security(struct msg_msg *msg) 3945 { 3946 msg_msg_free_security(msg); 3947 } 3948 3949 /* message queue security operations */ 3950 static int selinux_msg_queue_alloc_security(struct msg_queue *msq) 3951 { 3952 struct task_security_struct *tsec; 3953 struct ipc_security_struct *isec; 3954 struct avc_audit_data ad; 3955 int rc; 3956 3957 rc = ipc_alloc_security(current, &msq->q_perm, SECCLASS_MSGQ); 3958 if (rc) 3959 return rc; 3960 3961 tsec = current->security; 3962 isec = msq->q_perm.security; 3963 3964 AVC_AUDIT_DATA_INIT(&ad, IPC); 3965 ad.u.ipc_id = msq->q_perm.key; 3966 3967 rc = avc_has_perm(tsec->sid, isec->sid, SECCLASS_MSGQ, 3968 MSGQ__CREATE, &ad); 3969 if (rc) { 3970 ipc_free_security(&msq->q_perm); 3971 return rc; 3972 } 3973 return 0; 3974 } 3975 3976 static void selinux_msg_queue_free_security(struct msg_queue *msq) 3977 { 3978 ipc_free_security(&msq->q_perm); 3979 } 3980 3981 static int selinux_msg_queue_associate(struct msg_queue *msq, int msqflg) 3982 { 3983 struct task_security_struct *tsec; 3984 struct ipc_security_struct *isec; 3985 struct avc_audit_data ad; 3986 3987 tsec = current->security; 3988 isec = msq->q_perm.security; 3989 3990 AVC_AUDIT_DATA_INIT(&ad, IPC); 3991 ad.u.ipc_id = msq->q_perm.key; 3992 3993 return avc_has_perm(tsec->sid, isec->sid, SECCLASS_MSGQ, 3994 MSGQ__ASSOCIATE, &ad); 3995 } 3996 3997 static int selinux_msg_queue_msgctl(struct msg_queue *msq, int cmd) 3998 { 3999 int err; 4000 int perms; 4001 4002 switch(cmd) { 4003 case IPC_INFO: 4004 case MSG_INFO: 4005 /* No specific object, just general system-wide information. */ 4006 return task_has_system(current, SYSTEM__IPC_INFO); 4007 case IPC_STAT: 4008 case MSG_STAT: 4009 perms = MSGQ__GETATTR | MSGQ__ASSOCIATE; 4010 break; 4011 case IPC_SET: 4012 perms = MSGQ__SETATTR; 4013 break; 4014 case IPC_RMID: 4015 perms = MSGQ__DESTROY; 4016 break; 4017 default: 4018 return 0; 4019 } 4020 4021 err = ipc_has_perm(&msq->q_perm, perms); 4022 return err; 4023 } 4024 4025 static int selinux_msg_queue_msgsnd(struct msg_queue *msq, struct msg_msg *msg, int msqflg) 4026 { 4027 struct task_security_struct *tsec; 4028 struct ipc_security_struct *isec; 4029 struct msg_security_struct *msec; 4030 struct avc_audit_data ad; 4031 int rc; 4032 4033 tsec = current->security; 4034 isec = msq->q_perm.security; 4035 msec = msg->security; 4036 4037 /* 4038 * First time through, need to assign label to the message 4039 */ 4040 if (msec->sid == SECINITSID_UNLABELED) { 4041 /* 4042 * Compute new sid based on current process and 4043 * message queue this message will be stored in 4044 */ 4045 rc = security_transition_sid(tsec->sid, 4046 isec->sid, 4047 SECCLASS_MSG, 4048 &msec->sid); 4049 if (rc) 4050 return rc; 4051 } 4052 4053 AVC_AUDIT_DATA_INIT(&ad, IPC); 4054 ad.u.ipc_id = msq->q_perm.key; 4055 4056 /* Can this process write to the queue? */ 4057 rc = avc_has_perm(tsec->sid, isec->sid, SECCLASS_MSGQ, 4058 MSGQ__WRITE, &ad); 4059 if (!rc) 4060 /* Can this process send the message */ 4061 rc = avc_has_perm(tsec->sid, msec->sid, 4062 SECCLASS_MSG, MSG__SEND, &ad); 4063 if (!rc) 4064 /* Can the message be put in the queue? */ 4065 rc = avc_has_perm(msec->sid, isec->sid, 4066 SECCLASS_MSGQ, MSGQ__ENQUEUE, &ad); 4067 4068 return rc; 4069 } 4070 4071 static int selinux_msg_queue_msgrcv(struct msg_queue *msq, struct msg_msg *msg, 4072 struct task_struct *target, 4073 long type, int mode) 4074 { 4075 struct task_security_struct *tsec; 4076 struct ipc_security_struct *isec; 4077 struct msg_security_struct *msec; 4078 struct avc_audit_data ad; 4079 int rc; 4080 4081 tsec = target->security; 4082 isec = msq->q_perm.security; 4083 msec = msg->security; 4084 4085 AVC_AUDIT_DATA_INIT(&ad, IPC); 4086 ad.u.ipc_id = msq->q_perm.key; 4087 4088 rc = avc_has_perm(tsec->sid, isec->sid, 4089 SECCLASS_MSGQ, MSGQ__READ, &ad); 4090 if (!rc) 4091 rc = avc_has_perm(tsec->sid, msec->sid, 4092 SECCLASS_MSG, MSG__RECEIVE, &ad); 4093 return rc; 4094 } 4095 4096 /* Shared Memory security operations */ 4097 static int selinux_shm_alloc_security(struct shmid_kernel *shp) 4098 { 4099 struct task_security_struct *tsec; 4100 struct ipc_security_struct *isec; 4101 struct avc_audit_data ad; 4102 int rc; 4103 4104 rc = ipc_alloc_security(current, &shp->shm_perm, SECCLASS_SHM); 4105 if (rc) 4106 return rc; 4107 4108 tsec = current->security; 4109 isec = shp->shm_perm.security; 4110 4111 AVC_AUDIT_DATA_INIT(&ad, IPC); 4112 ad.u.ipc_id = shp->shm_perm.key; 4113 4114 rc = avc_has_perm(tsec->sid, isec->sid, SECCLASS_SHM, 4115 SHM__CREATE, &ad); 4116 if (rc) { 4117 ipc_free_security(&shp->shm_perm); 4118 return rc; 4119 } 4120 return 0; 4121 } 4122 4123 static void selinux_shm_free_security(struct shmid_kernel *shp) 4124 { 4125 ipc_free_security(&shp->shm_perm); 4126 } 4127 4128 static int selinux_shm_associate(struct shmid_kernel *shp, int shmflg) 4129 { 4130 struct task_security_struct *tsec; 4131 struct ipc_security_struct *isec; 4132 struct avc_audit_data ad; 4133 4134 tsec = current->security; 4135 isec = shp->shm_perm.security; 4136 4137 AVC_AUDIT_DATA_INIT(&ad, IPC); 4138 ad.u.ipc_id = shp->shm_perm.key; 4139 4140 return avc_has_perm(tsec->sid, isec->sid, SECCLASS_SHM, 4141 SHM__ASSOCIATE, &ad); 4142 } 4143 4144 /* Note, at this point, shp is locked down */ 4145 static int selinux_shm_shmctl(struct shmid_kernel *shp, int cmd) 4146 { 4147 int perms; 4148 int err; 4149 4150 switch(cmd) { 4151 case IPC_INFO: 4152 case SHM_INFO: 4153 /* No specific object, just general system-wide information. */ 4154 return task_has_system(current, SYSTEM__IPC_INFO); 4155 case IPC_STAT: 4156 case SHM_STAT: 4157 perms = SHM__GETATTR | SHM__ASSOCIATE; 4158 break; 4159 case IPC_SET: 4160 perms = SHM__SETATTR; 4161 break; 4162 case SHM_LOCK: 4163 case SHM_UNLOCK: 4164 perms = SHM__LOCK; 4165 break; 4166 case IPC_RMID: 4167 perms = SHM__DESTROY; 4168 break; 4169 default: 4170 return 0; 4171 } 4172 4173 err = ipc_has_perm(&shp->shm_perm, perms); 4174 return err; 4175 } 4176 4177 static int selinux_shm_shmat(struct shmid_kernel *shp, 4178 char __user *shmaddr, int shmflg) 4179 { 4180 u32 perms; 4181 int rc; 4182 4183 rc = secondary_ops->shm_shmat(shp, shmaddr, shmflg); 4184 if (rc) 4185 return rc; 4186 4187 if (shmflg & SHM_RDONLY) 4188 perms = SHM__READ; 4189 else 4190 perms = SHM__READ | SHM__WRITE; 4191 4192 return ipc_has_perm(&shp->shm_perm, perms); 4193 } 4194 4195 /* Semaphore security operations */ 4196 static int selinux_sem_alloc_security(struct sem_array *sma) 4197 { 4198 struct task_security_struct *tsec; 4199 struct ipc_security_struct *isec; 4200 struct avc_audit_data ad; 4201 int rc; 4202 4203 rc = ipc_alloc_security(current, &sma->sem_perm, SECCLASS_SEM); 4204 if (rc) 4205 return rc; 4206 4207 tsec = current->security; 4208 isec = sma->sem_perm.security; 4209 4210 AVC_AUDIT_DATA_INIT(&ad, IPC); 4211 ad.u.ipc_id = sma->sem_perm.key; 4212 4213 rc = avc_has_perm(tsec->sid, isec->sid, SECCLASS_SEM, 4214 SEM__CREATE, &ad); 4215 if (rc) { 4216 ipc_free_security(&sma->sem_perm); 4217 return rc; 4218 } 4219 return 0; 4220 } 4221 4222 static void selinux_sem_free_security(struct sem_array *sma) 4223 { 4224 ipc_free_security(&sma->sem_perm); 4225 } 4226 4227 static int selinux_sem_associate(struct sem_array *sma, int semflg) 4228 { 4229 struct task_security_struct *tsec; 4230 struct ipc_security_struct *isec; 4231 struct avc_audit_data ad; 4232 4233 tsec = current->security; 4234 isec = sma->sem_perm.security; 4235 4236 AVC_AUDIT_DATA_INIT(&ad, IPC); 4237 ad.u.ipc_id = sma->sem_perm.key; 4238 4239 return avc_has_perm(tsec->sid, isec->sid, SECCLASS_SEM, 4240 SEM__ASSOCIATE, &ad); 4241 } 4242 4243 /* Note, at this point, sma is locked down */ 4244 static int selinux_sem_semctl(struct sem_array *sma, int cmd) 4245 { 4246 int err; 4247 u32 perms; 4248 4249 switch(cmd) { 4250 case IPC_INFO: 4251 case SEM_INFO: 4252 /* No specific object, just general system-wide information. */ 4253 return task_has_system(current, SYSTEM__IPC_INFO); 4254 case GETPID: 4255 case GETNCNT: 4256 case GETZCNT: 4257 perms = SEM__GETATTR; 4258 break; 4259 case GETVAL: 4260 case GETALL: 4261 perms = SEM__READ; 4262 break; 4263 case SETVAL: 4264 case SETALL: 4265 perms = SEM__WRITE; 4266 break; 4267 case IPC_RMID: 4268 perms = SEM__DESTROY; 4269 break; 4270 case IPC_SET: 4271 perms = SEM__SETATTR; 4272 break; 4273 case IPC_STAT: 4274 case SEM_STAT: 4275 perms = SEM__GETATTR | SEM__ASSOCIATE; 4276 break; 4277 default: 4278 return 0; 4279 } 4280 4281 err = ipc_has_perm(&sma->sem_perm, perms); 4282 return err; 4283 } 4284 4285 static int selinux_sem_semop(struct sem_array *sma, 4286 struct sembuf *sops, unsigned nsops, int alter) 4287 { 4288 u32 perms; 4289 4290 if (alter) 4291 perms = SEM__READ | SEM__WRITE; 4292 else 4293 perms = SEM__READ; 4294 4295 return ipc_has_perm(&sma->sem_perm, perms); 4296 } 4297 4298 static int selinux_ipc_permission(struct kern_ipc_perm *ipcp, short flag) 4299 { 4300 u32 av = 0; 4301 4302 av = 0; 4303 if (flag & S_IRUGO) 4304 av |= IPC__UNIX_READ; 4305 if (flag & S_IWUGO) 4306 av |= IPC__UNIX_WRITE; 4307 4308 if (av == 0) 4309 return 0; 4310 4311 return ipc_has_perm(ipcp, av); 4312 } 4313 4314 /* module stacking operations */ 4315 static int selinux_register_security (const char *name, struct security_operations *ops) 4316 { 4317 if (secondary_ops != original_ops) { 4318 printk(KERN_INFO "%s: There is already a secondary security " 4319 "module registered.\n", __FUNCTION__); 4320 return -EINVAL; 4321 } 4322 4323 secondary_ops = ops; 4324 4325 printk(KERN_INFO "%s: Registering secondary module %s\n", 4326 __FUNCTION__, 4327 name); 4328 4329 return 0; 4330 } 4331 4332 static int selinux_unregister_security (const char *name, struct security_operations *ops) 4333 { 4334 if (ops != secondary_ops) { 4335 printk (KERN_INFO "%s: trying to unregister a security module " 4336 "that is not registered.\n", __FUNCTION__); 4337 return -EINVAL; 4338 } 4339 4340 secondary_ops = original_ops; 4341 4342 return 0; 4343 } 4344 4345 static void selinux_d_instantiate (struct dentry *dentry, struct inode *inode) 4346 { 4347 if (inode) 4348 inode_doinit_with_dentry(inode, dentry); 4349 } 4350 4351 static int selinux_getprocattr(struct task_struct *p, 4352 char *name, void *value, size_t size) 4353 { 4354 struct task_security_struct *tsec; 4355 u32 sid; 4356 int error; 4357 4358 if (current != p) { 4359 error = task_has_perm(current, p, PROCESS__GETATTR); 4360 if (error) 4361 return error; 4362 } 4363 4364 tsec = p->security; 4365 4366 if (!strcmp(name, "current")) 4367 sid = tsec->sid; 4368 else if (!strcmp(name, "prev")) 4369 sid = tsec->osid; 4370 else if (!strcmp(name, "exec")) 4371 sid = tsec->exec_sid; 4372 else if (!strcmp(name, "fscreate")) 4373 sid = tsec->create_sid; 4374 else if (!strcmp(name, "keycreate")) 4375 sid = tsec->keycreate_sid; 4376 else if (!strcmp(name, "sockcreate")) 4377 sid = tsec->sockcreate_sid; 4378 else 4379 return -EINVAL; 4380 4381 if (!sid) 4382 return 0; 4383 4384 return selinux_getsecurity(sid, value, size); 4385 } 4386 4387 static int selinux_setprocattr(struct task_struct *p, 4388 char *name, void *value, size_t size) 4389 { 4390 struct task_security_struct *tsec; 4391 u32 sid = 0; 4392 int error; 4393 char *str = value; 4394 4395 if (current != p) { 4396 /* SELinux only allows a process to change its own 4397 security attributes. */ 4398 return -EACCES; 4399 } 4400 4401 /* 4402 * Basic control over ability to set these attributes at all. 4403 * current == p, but we'll pass them separately in case the 4404 * above restriction is ever removed. 4405 */ 4406 if (!strcmp(name, "exec")) 4407 error = task_has_perm(current, p, PROCESS__SETEXEC); 4408 else if (!strcmp(name, "fscreate")) 4409 error = task_has_perm(current, p, PROCESS__SETFSCREATE); 4410 else if (!strcmp(name, "keycreate")) 4411 error = task_has_perm(current, p, PROCESS__SETKEYCREATE); 4412 else if (!strcmp(name, "sockcreate")) 4413 error = task_has_perm(current, p, PROCESS__SETSOCKCREATE); 4414 else if (!strcmp(name, "current")) 4415 error = task_has_perm(current, p, PROCESS__SETCURRENT); 4416 else 4417 error = -EINVAL; 4418 if (error) 4419 return error; 4420 4421 /* Obtain a SID for the context, if one was specified. */ 4422 if (size && str[1] && str[1] != '\n') { 4423 if (str[size-1] == '\n') { 4424 str[size-1] = 0; 4425 size--; 4426 } 4427 error = security_context_to_sid(value, size, &sid); 4428 if (error) 4429 return error; 4430 } 4431 4432 /* Permission checking based on the specified context is 4433 performed during the actual operation (execve, 4434 open/mkdir/...), when we know the full context of the 4435 operation. See selinux_bprm_set_security for the execve 4436 checks and may_create for the file creation checks. The 4437 operation will then fail if the context is not permitted. */ 4438 tsec = p->security; 4439 if (!strcmp(name, "exec")) 4440 tsec->exec_sid = sid; 4441 else if (!strcmp(name, "fscreate")) 4442 tsec->create_sid = sid; 4443 else if (!strcmp(name, "keycreate")) { 4444 error = may_create_key(sid, p); 4445 if (error) 4446 return error; 4447 tsec->keycreate_sid = sid; 4448 } else if (!strcmp(name, "sockcreate")) 4449 tsec->sockcreate_sid = sid; 4450 else if (!strcmp(name, "current")) { 4451 struct av_decision avd; 4452 4453 if (sid == 0) 4454 return -EINVAL; 4455 4456 /* Only allow single threaded processes to change context */ 4457 if (atomic_read(&p->mm->mm_users) != 1) { 4458 struct task_struct *g, *t; 4459 struct mm_struct *mm = p->mm; 4460 read_lock(&tasklist_lock); 4461 do_each_thread(g, t) 4462 if (t->mm == mm && t != p) { 4463 read_unlock(&tasklist_lock); 4464 return -EPERM; 4465 } 4466 while_each_thread(g, t); 4467 read_unlock(&tasklist_lock); 4468 } 4469 4470 /* Check permissions for the transition. */ 4471 error = avc_has_perm(tsec->sid, sid, SECCLASS_PROCESS, 4472 PROCESS__DYNTRANSITION, NULL); 4473 if (error) 4474 return error; 4475 4476 /* Check for ptracing, and update the task SID if ok. 4477 Otherwise, leave SID unchanged and fail. */ 4478 task_lock(p); 4479 if (p->ptrace & PT_PTRACED) { 4480 error = avc_has_perm_noaudit(tsec->ptrace_sid, sid, 4481 SECCLASS_PROCESS, 4482 PROCESS__PTRACE, &avd); 4483 if (!error) 4484 tsec->sid = sid; 4485 task_unlock(p); 4486 avc_audit(tsec->ptrace_sid, sid, SECCLASS_PROCESS, 4487 PROCESS__PTRACE, &avd, error, NULL); 4488 if (error) 4489 return error; 4490 } else { 4491 tsec->sid = sid; 4492 task_unlock(p); 4493 } 4494 } 4495 else 4496 return -EINVAL; 4497 4498 return size; 4499 } 4500 4501 static int selinux_secid_to_secctx(u32 secid, char **secdata, u32 *seclen) 4502 { 4503 return security_sid_to_context(secid, secdata, seclen); 4504 } 4505 4506 static void selinux_release_secctx(char *secdata, u32 seclen) 4507 { 4508 if (secdata) 4509 kfree(secdata); 4510 } 4511 4512 #ifdef CONFIG_KEYS 4513 4514 static int selinux_key_alloc(struct key *k, struct task_struct *tsk, 4515 unsigned long flags) 4516 { 4517 struct task_security_struct *tsec = tsk->security; 4518 struct key_security_struct *ksec; 4519 4520 ksec = kzalloc(sizeof(struct key_security_struct), GFP_KERNEL); 4521 if (!ksec) 4522 return -ENOMEM; 4523 4524 ksec->obj = k; 4525 if (tsec->keycreate_sid) 4526 ksec->sid = tsec->keycreate_sid; 4527 else 4528 ksec->sid = tsec->sid; 4529 k->security = ksec; 4530 4531 return 0; 4532 } 4533 4534 static void selinux_key_free(struct key *k) 4535 { 4536 struct key_security_struct *ksec = k->security; 4537 4538 k->security = NULL; 4539 kfree(ksec); 4540 } 4541 4542 static int selinux_key_permission(key_ref_t key_ref, 4543 struct task_struct *ctx, 4544 key_perm_t perm) 4545 { 4546 struct key *key; 4547 struct task_security_struct *tsec; 4548 struct key_security_struct *ksec; 4549 4550 key = key_ref_to_ptr(key_ref); 4551 4552 tsec = ctx->security; 4553 ksec = key->security; 4554 4555 /* if no specific permissions are requested, we skip the 4556 permission check. No serious, additional covert channels 4557 appear to be created. */ 4558 if (perm == 0) 4559 return 0; 4560 4561 return avc_has_perm(tsec->sid, ksec->sid, 4562 SECCLASS_KEY, perm, NULL); 4563 } 4564 4565 #endif 4566 4567 static struct security_operations selinux_ops = { 4568 .ptrace = selinux_ptrace, 4569 .capget = selinux_capget, 4570 .capset_check = selinux_capset_check, 4571 .capset_set = selinux_capset_set, 4572 .sysctl = selinux_sysctl, 4573 .capable = selinux_capable, 4574 .quotactl = selinux_quotactl, 4575 .quota_on = selinux_quota_on, 4576 .syslog = selinux_syslog, 4577 .vm_enough_memory = selinux_vm_enough_memory, 4578 4579 .netlink_send = selinux_netlink_send, 4580 .netlink_recv = selinux_netlink_recv, 4581 4582 .bprm_alloc_security = selinux_bprm_alloc_security, 4583 .bprm_free_security = selinux_bprm_free_security, 4584 .bprm_apply_creds = selinux_bprm_apply_creds, 4585 .bprm_post_apply_creds = selinux_bprm_post_apply_creds, 4586 .bprm_set_security = selinux_bprm_set_security, 4587 .bprm_check_security = selinux_bprm_check_security, 4588 .bprm_secureexec = selinux_bprm_secureexec, 4589 4590 .sb_alloc_security = selinux_sb_alloc_security, 4591 .sb_free_security = selinux_sb_free_security, 4592 .sb_copy_data = selinux_sb_copy_data, 4593 .sb_kern_mount = selinux_sb_kern_mount, 4594 .sb_statfs = selinux_sb_statfs, 4595 .sb_mount = selinux_mount, 4596 .sb_umount = selinux_umount, 4597 4598 .inode_alloc_security = selinux_inode_alloc_security, 4599 .inode_free_security = selinux_inode_free_security, 4600 .inode_init_security = selinux_inode_init_security, 4601 .inode_create = selinux_inode_create, 4602 .inode_link = selinux_inode_link, 4603 .inode_unlink = selinux_inode_unlink, 4604 .inode_symlink = selinux_inode_symlink, 4605 .inode_mkdir = selinux_inode_mkdir, 4606 .inode_rmdir = selinux_inode_rmdir, 4607 .inode_mknod = selinux_inode_mknod, 4608 .inode_rename = selinux_inode_rename, 4609 .inode_readlink = selinux_inode_readlink, 4610 .inode_follow_link = selinux_inode_follow_link, 4611 .inode_permission = selinux_inode_permission, 4612 .inode_setattr = selinux_inode_setattr, 4613 .inode_getattr = selinux_inode_getattr, 4614 .inode_setxattr = selinux_inode_setxattr, 4615 .inode_post_setxattr = selinux_inode_post_setxattr, 4616 .inode_getxattr = selinux_inode_getxattr, 4617 .inode_listxattr = selinux_inode_listxattr, 4618 .inode_removexattr = selinux_inode_removexattr, 4619 .inode_xattr_getsuffix = selinux_inode_xattr_getsuffix, 4620 .inode_getsecurity = selinux_inode_getsecurity, 4621 .inode_setsecurity = selinux_inode_setsecurity, 4622 .inode_listsecurity = selinux_inode_listsecurity, 4623 4624 .file_permission = selinux_file_permission, 4625 .file_alloc_security = selinux_file_alloc_security, 4626 .file_free_security = selinux_file_free_security, 4627 .file_ioctl = selinux_file_ioctl, 4628 .file_mmap = selinux_file_mmap, 4629 .file_mprotect = selinux_file_mprotect, 4630 .file_lock = selinux_file_lock, 4631 .file_fcntl = selinux_file_fcntl, 4632 .file_set_fowner = selinux_file_set_fowner, 4633 .file_send_sigiotask = selinux_file_send_sigiotask, 4634 .file_receive = selinux_file_receive, 4635 4636 .task_create = selinux_task_create, 4637 .task_alloc_security = selinux_task_alloc_security, 4638 .task_free_security = selinux_task_free_security, 4639 .task_setuid = selinux_task_setuid, 4640 .task_post_setuid = selinux_task_post_setuid, 4641 .task_setgid = selinux_task_setgid, 4642 .task_setpgid = selinux_task_setpgid, 4643 .task_getpgid = selinux_task_getpgid, 4644 .task_getsid = selinux_task_getsid, 4645 .task_getsecid = selinux_task_getsecid, 4646 .task_setgroups = selinux_task_setgroups, 4647 .task_setnice = selinux_task_setnice, 4648 .task_setioprio = selinux_task_setioprio, 4649 .task_getioprio = selinux_task_getioprio, 4650 .task_setrlimit = selinux_task_setrlimit, 4651 .task_setscheduler = selinux_task_setscheduler, 4652 .task_getscheduler = selinux_task_getscheduler, 4653 .task_movememory = selinux_task_movememory, 4654 .task_kill = selinux_task_kill, 4655 .task_wait = selinux_task_wait, 4656 .task_prctl = selinux_task_prctl, 4657 .task_reparent_to_init = selinux_task_reparent_to_init, 4658 .task_to_inode = selinux_task_to_inode, 4659 4660 .ipc_permission = selinux_ipc_permission, 4661 4662 .msg_msg_alloc_security = selinux_msg_msg_alloc_security, 4663 .msg_msg_free_security = selinux_msg_msg_free_security, 4664 4665 .msg_queue_alloc_security = selinux_msg_queue_alloc_security, 4666 .msg_queue_free_security = selinux_msg_queue_free_security, 4667 .msg_queue_associate = selinux_msg_queue_associate, 4668 .msg_queue_msgctl = selinux_msg_queue_msgctl, 4669 .msg_queue_msgsnd = selinux_msg_queue_msgsnd, 4670 .msg_queue_msgrcv = selinux_msg_queue_msgrcv, 4671 4672 .shm_alloc_security = selinux_shm_alloc_security, 4673 .shm_free_security = selinux_shm_free_security, 4674 .shm_associate = selinux_shm_associate, 4675 .shm_shmctl = selinux_shm_shmctl, 4676 .shm_shmat = selinux_shm_shmat, 4677 4678 .sem_alloc_security = selinux_sem_alloc_security, 4679 .sem_free_security = selinux_sem_free_security, 4680 .sem_associate = selinux_sem_associate, 4681 .sem_semctl = selinux_sem_semctl, 4682 .sem_semop = selinux_sem_semop, 4683 4684 .register_security = selinux_register_security, 4685 .unregister_security = selinux_unregister_security, 4686 4687 .d_instantiate = selinux_d_instantiate, 4688 4689 .getprocattr = selinux_getprocattr, 4690 .setprocattr = selinux_setprocattr, 4691 4692 .secid_to_secctx = selinux_secid_to_secctx, 4693 .release_secctx = selinux_release_secctx, 4694 4695 .unix_stream_connect = selinux_socket_unix_stream_connect, 4696 .unix_may_send = selinux_socket_unix_may_send, 4697 4698 .socket_create = selinux_socket_create, 4699 .socket_post_create = selinux_socket_post_create, 4700 .socket_bind = selinux_socket_bind, 4701 .socket_connect = selinux_socket_connect, 4702 .socket_listen = selinux_socket_listen, 4703 .socket_accept = selinux_socket_accept, 4704 .socket_sendmsg = selinux_socket_sendmsg, 4705 .socket_recvmsg = selinux_socket_recvmsg, 4706 .socket_getsockname = selinux_socket_getsockname, 4707 .socket_getpeername = selinux_socket_getpeername, 4708 .socket_getsockopt = selinux_socket_getsockopt, 4709 .socket_setsockopt = selinux_socket_setsockopt, 4710 .socket_shutdown = selinux_socket_shutdown, 4711 .socket_sock_rcv_skb = selinux_socket_sock_rcv_skb, 4712 .socket_getpeersec_stream = selinux_socket_getpeersec_stream, 4713 .socket_getpeersec_dgram = selinux_socket_getpeersec_dgram, 4714 .sk_alloc_security = selinux_sk_alloc_security, 4715 .sk_free_security = selinux_sk_free_security, 4716 .sk_clone_security = selinux_sk_clone_security, 4717 .sk_getsecid = selinux_sk_getsecid, 4718 .sock_graft = selinux_sock_graft, 4719 .inet_conn_request = selinux_inet_conn_request, 4720 .inet_csk_clone = selinux_inet_csk_clone, 4721 .req_classify_flow = selinux_req_classify_flow, 4722 4723 #ifdef CONFIG_SECURITY_NETWORK_XFRM 4724 .xfrm_policy_alloc_security = selinux_xfrm_policy_alloc, 4725 .xfrm_policy_clone_security = selinux_xfrm_policy_clone, 4726 .xfrm_policy_free_security = selinux_xfrm_policy_free, 4727 .xfrm_policy_delete_security = selinux_xfrm_policy_delete, 4728 .xfrm_state_alloc_security = selinux_xfrm_state_alloc, 4729 .xfrm_state_free_security = selinux_xfrm_state_free, 4730 .xfrm_state_delete_security = selinux_xfrm_state_delete, 4731 .xfrm_policy_lookup = selinux_xfrm_policy_lookup, 4732 .xfrm_state_pol_flow_match = selinux_xfrm_state_pol_flow_match, 4733 .xfrm_flow_state_match = selinux_xfrm_flow_state_match, 4734 .xfrm_decode_session = selinux_xfrm_decode_session, 4735 #endif 4736 4737 #ifdef CONFIG_KEYS 4738 .key_alloc = selinux_key_alloc, 4739 .key_free = selinux_key_free, 4740 .key_permission = selinux_key_permission, 4741 #endif 4742 }; 4743 4744 static __init int selinux_init(void) 4745 { 4746 struct task_security_struct *tsec; 4747 4748 if (!selinux_enabled) { 4749 printk(KERN_INFO "SELinux: Disabled at boot.\n"); 4750 return 0; 4751 } 4752 4753 printk(KERN_INFO "SELinux: Initializing.\n"); 4754 4755 /* Set the security state for the initial task. */ 4756 if (task_alloc_security(current)) 4757 panic("SELinux: Failed to initialize initial task.\n"); 4758 tsec = current->security; 4759 tsec->osid = tsec->sid = SECINITSID_KERNEL; 4760 4761 sel_inode_cache = kmem_cache_create("selinux_inode_security", 4762 sizeof(struct inode_security_struct), 4763 0, SLAB_PANIC, NULL, NULL); 4764 avc_init(); 4765 4766 original_ops = secondary_ops = security_ops; 4767 if (!secondary_ops) 4768 panic ("SELinux: No initial security operations\n"); 4769 if (register_security (&selinux_ops)) 4770 panic("SELinux: Unable to register with kernel.\n"); 4771 4772 if (selinux_enforcing) { 4773 printk(KERN_INFO "SELinux: Starting in enforcing mode\n"); 4774 } else { 4775 printk(KERN_INFO "SELinux: Starting in permissive mode\n"); 4776 } 4777 4778 #ifdef CONFIG_KEYS 4779 /* Add security information to initial keyrings */ 4780 selinux_key_alloc(&root_user_keyring, current, 4781 KEY_ALLOC_NOT_IN_QUOTA); 4782 selinux_key_alloc(&root_session_keyring, current, 4783 KEY_ALLOC_NOT_IN_QUOTA); 4784 #endif 4785 4786 return 0; 4787 } 4788 4789 void selinux_complete_init(void) 4790 { 4791 printk(KERN_INFO "SELinux: Completing initialization.\n"); 4792 4793 /* Set up any superblocks initialized prior to the policy load. */ 4794 printk(KERN_INFO "SELinux: Setting up existing superblocks.\n"); 4795 spin_lock(&sb_lock); 4796 spin_lock(&sb_security_lock); 4797 next_sb: 4798 if (!list_empty(&superblock_security_head)) { 4799 struct superblock_security_struct *sbsec = 4800 list_entry(superblock_security_head.next, 4801 struct superblock_security_struct, 4802 list); 4803 struct super_block *sb = sbsec->sb; 4804 sb->s_count++; 4805 spin_unlock(&sb_security_lock); 4806 spin_unlock(&sb_lock); 4807 down_read(&sb->s_umount); 4808 if (sb->s_root) 4809 superblock_doinit(sb, NULL); 4810 drop_super(sb); 4811 spin_lock(&sb_lock); 4812 spin_lock(&sb_security_lock); 4813 list_del_init(&sbsec->list); 4814 goto next_sb; 4815 } 4816 spin_unlock(&sb_security_lock); 4817 spin_unlock(&sb_lock); 4818 } 4819 4820 /* SELinux requires early initialization in order to label 4821 all processes and objects when they are created. */ 4822 security_initcall(selinux_init); 4823 4824 #if defined(CONFIG_NETFILTER) 4825 4826 static struct nf_hook_ops selinux_ipv4_op = { 4827 .hook = selinux_ipv4_postroute_last, 4828 .owner = THIS_MODULE, 4829 .pf = PF_INET, 4830 .hooknum = NF_IP_POST_ROUTING, 4831 .priority = NF_IP_PRI_SELINUX_LAST, 4832 }; 4833 4834 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE) 4835 4836 static struct nf_hook_ops selinux_ipv6_op = { 4837 .hook = selinux_ipv6_postroute_last, 4838 .owner = THIS_MODULE, 4839 .pf = PF_INET6, 4840 .hooknum = NF_IP6_POST_ROUTING, 4841 .priority = NF_IP6_PRI_SELINUX_LAST, 4842 }; 4843 4844 #endif /* IPV6 */ 4845 4846 static int __init selinux_nf_ip_init(void) 4847 { 4848 int err = 0; 4849 4850 if (!selinux_enabled) 4851 goto out; 4852 4853 printk(KERN_INFO "SELinux: Registering netfilter hooks\n"); 4854 4855 err = nf_register_hook(&selinux_ipv4_op); 4856 if (err) 4857 panic("SELinux: nf_register_hook for IPv4: error %d\n", err); 4858 4859 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE) 4860 4861 err = nf_register_hook(&selinux_ipv6_op); 4862 if (err) 4863 panic("SELinux: nf_register_hook for IPv6: error %d\n", err); 4864 4865 #endif /* IPV6 */ 4866 4867 out: 4868 return err; 4869 } 4870 4871 __initcall(selinux_nf_ip_init); 4872 4873 #ifdef CONFIG_SECURITY_SELINUX_DISABLE 4874 static void selinux_nf_ip_exit(void) 4875 { 4876 printk(KERN_INFO "SELinux: Unregistering netfilter hooks\n"); 4877 4878 nf_unregister_hook(&selinux_ipv4_op); 4879 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE) 4880 nf_unregister_hook(&selinux_ipv6_op); 4881 #endif /* IPV6 */ 4882 } 4883 #endif 4884 4885 #else /* CONFIG_NETFILTER */ 4886 4887 #ifdef CONFIG_SECURITY_SELINUX_DISABLE 4888 #define selinux_nf_ip_exit() 4889 #endif 4890 4891 #endif /* CONFIG_NETFILTER */ 4892 4893 #ifdef CONFIG_SECURITY_SELINUX_DISABLE 4894 int selinux_disable(void) 4895 { 4896 extern void exit_sel_fs(void); 4897 static int selinux_disabled = 0; 4898 4899 if (ss_initialized) { 4900 /* Not permitted after initial policy load. */ 4901 return -EINVAL; 4902 } 4903 4904 if (selinux_disabled) { 4905 /* Only do this once. */ 4906 return -EINVAL; 4907 } 4908 4909 printk(KERN_INFO "SELinux: Disabled at runtime.\n"); 4910 4911 selinux_disabled = 1; 4912 selinux_enabled = 0; 4913 4914 /* Reset security_ops to the secondary module, dummy or capability. */ 4915 security_ops = secondary_ops; 4916 4917 /* Unregister netfilter hooks. */ 4918 selinux_nf_ip_exit(); 4919 4920 /* Unregister selinuxfs. */ 4921 exit_sel_fs(); 4922 4923 return 0; 4924 } 4925 #endif 4926 4927 4928