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 * 16 * This program is free software; you can redistribute it and/or modify 17 * it under the terms of the GNU General Public License version 2, 18 * as published by the Free Software Foundation. 19 */ 20 21 #include <linux/config.h> 22 #include <linux/module.h> 23 #include <linux/init.h> 24 #include <linux/kernel.h> 25 #include <linux/ptrace.h> 26 #include <linux/errno.h> 27 #include <linux/sched.h> 28 #include <linux/security.h> 29 #include <linux/xattr.h> 30 #include <linux/capability.h> 31 #include <linux/unistd.h> 32 #include <linux/mm.h> 33 #include <linux/mman.h> 34 #include <linux/slab.h> 35 #include <linux/pagemap.h> 36 #include <linux/swap.h> 37 #include <linux/smp_lock.h> 38 #include <linux/spinlock.h> 39 #include <linux/syscalls.h> 40 #include <linux/file.h> 41 #include <linux/namei.h> 42 #include <linux/mount.h> 43 #include <linux/ext2_fs.h> 44 #include <linux/proc_fs.h> 45 #include <linux/kd.h> 46 #include <linux/netfilter_ipv4.h> 47 #include <linux/netfilter_ipv6.h> 48 #include <linux/tty.h> 49 #include <net/icmp.h> 50 #include <net/ip.h> /* for sysctl_local_port_range[] */ 51 #include <net/tcp.h> /* struct or_callable used in sock_rcv_skb */ 52 #include <asm/uaccess.h> 53 #include <asm/semaphore.h> 54 #include <asm/ioctls.h> 55 #include <linux/bitops.h> 56 #include <linux/interrupt.h> 57 #include <linux/netdevice.h> /* for network interface checks */ 58 #include <linux/netlink.h> 59 #include <linux/tcp.h> 60 #include <linux/udp.h> 61 #include <linux/quota.h> 62 #include <linux/un.h> /* for Unix socket types */ 63 #include <net/af_unix.h> /* for Unix socket types */ 64 #include <linux/parser.h> 65 #include <linux/nfs_mount.h> 66 #include <net/ipv6.h> 67 #include <linux/hugetlb.h> 68 #include <linux/personality.h> 69 #include <linux/sysctl.h> 70 #include <linux/audit.h> 71 #include <linux/string.h> 72 73 #include "avc.h" 74 #include "objsec.h" 75 #include "netif.h" 76 #include "xfrm.h" 77 78 #define XATTR_SELINUX_SUFFIX "selinux" 79 #define XATTR_NAME_SELINUX XATTR_SECURITY_PREFIX XATTR_SELINUX_SUFFIX 80 81 extern unsigned int policydb_loaded_version; 82 extern int selinux_nlmsg_lookup(u16 sclass, u16 nlmsg_type, u32 *perm); 83 84 #ifdef CONFIG_SECURITY_SELINUX_DEVELOP 85 int selinux_enforcing = 0; 86 87 static int __init enforcing_setup(char *str) 88 { 89 selinux_enforcing = simple_strtol(str,NULL,0); 90 return 1; 91 } 92 __setup("enforcing=", enforcing_setup); 93 #endif 94 95 #ifdef CONFIG_SECURITY_SELINUX_BOOTPARAM 96 int selinux_enabled = CONFIG_SECURITY_SELINUX_BOOTPARAM_VALUE; 97 98 static int __init selinux_enabled_setup(char *str) 99 { 100 selinux_enabled = simple_strtol(str, NULL, 0); 101 return 1; 102 } 103 __setup("selinux=", selinux_enabled_setup); 104 #endif 105 106 /* Original (dummy) security module. */ 107 static struct security_operations *original_ops = NULL; 108 109 /* Minimal support for a secondary security module, 110 just to allow the use of the dummy or capability modules. 111 The owlsm module can alternatively be used as a secondary 112 module as long as CONFIG_OWLSM_FD is not enabled. */ 113 static struct security_operations *secondary_ops = NULL; 114 115 /* Lists of inode and superblock security structures initialized 116 before the policy was loaded. */ 117 static LIST_HEAD(superblock_security_head); 118 static DEFINE_SPINLOCK(sb_security_lock); 119 120 /* Allocate and free functions for each kind of security blob. */ 121 122 static int task_alloc_security(struct task_struct *task) 123 { 124 struct task_security_struct *tsec; 125 126 tsec = kzalloc(sizeof(struct task_security_struct), GFP_KERNEL); 127 if (!tsec) 128 return -ENOMEM; 129 130 tsec->magic = SELINUX_MAGIC; 131 tsec->task = task; 132 tsec->osid = tsec->sid = tsec->ptrace_sid = SECINITSID_UNLABELED; 133 task->security = tsec; 134 135 return 0; 136 } 137 138 static void task_free_security(struct task_struct *task) 139 { 140 struct task_security_struct *tsec = task->security; 141 142 if (!tsec || tsec->magic != SELINUX_MAGIC) 143 return; 144 145 task->security = NULL; 146 kfree(tsec); 147 } 148 149 static int inode_alloc_security(struct inode *inode) 150 { 151 struct task_security_struct *tsec = current->security; 152 struct inode_security_struct *isec; 153 154 isec = kzalloc(sizeof(struct inode_security_struct), GFP_KERNEL); 155 if (!isec) 156 return -ENOMEM; 157 158 init_MUTEX(&isec->sem); 159 INIT_LIST_HEAD(&isec->list); 160 isec->magic = SELINUX_MAGIC; 161 isec->inode = inode; 162 isec->sid = SECINITSID_UNLABELED; 163 isec->sclass = SECCLASS_FILE; 164 if (tsec && tsec->magic == SELINUX_MAGIC) 165 isec->task_sid = tsec->sid; 166 else 167 isec->task_sid = SECINITSID_UNLABELED; 168 inode->i_security = isec; 169 170 return 0; 171 } 172 173 static void inode_free_security(struct inode *inode) 174 { 175 struct inode_security_struct *isec = inode->i_security; 176 struct superblock_security_struct *sbsec = inode->i_sb->s_security; 177 178 if (!isec || isec->magic != SELINUX_MAGIC) 179 return; 180 181 spin_lock(&sbsec->isec_lock); 182 if (!list_empty(&isec->list)) 183 list_del_init(&isec->list); 184 spin_unlock(&sbsec->isec_lock); 185 186 inode->i_security = NULL; 187 kfree(isec); 188 } 189 190 static int file_alloc_security(struct file *file) 191 { 192 struct task_security_struct *tsec = current->security; 193 struct file_security_struct *fsec; 194 195 fsec = kzalloc(sizeof(struct file_security_struct), GFP_ATOMIC); 196 if (!fsec) 197 return -ENOMEM; 198 199 fsec->magic = SELINUX_MAGIC; 200 fsec->file = file; 201 if (tsec && tsec->magic == SELINUX_MAGIC) { 202 fsec->sid = tsec->sid; 203 fsec->fown_sid = tsec->sid; 204 } else { 205 fsec->sid = SECINITSID_UNLABELED; 206 fsec->fown_sid = SECINITSID_UNLABELED; 207 } 208 file->f_security = fsec; 209 210 return 0; 211 } 212 213 static void file_free_security(struct file *file) 214 { 215 struct file_security_struct *fsec = file->f_security; 216 217 if (!fsec || fsec->magic != SELINUX_MAGIC) 218 return; 219 220 file->f_security = NULL; 221 kfree(fsec); 222 } 223 224 static int superblock_alloc_security(struct super_block *sb) 225 { 226 struct superblock_security_struct *sbsec; 227 228 sbsec = kzalloc(sizeof(struct superblock_security_struct), GFP_KERNEL); 229 if (!sbsec) 230 return -ENOMEM; 231 232 init_MUTEX(&sbsec->sem); 233 INIT_LIST_HEAD(&sbsec->list); 234 INIT_LIST_HEAD(&sbsec->isec_head); 235 spin_lock_init(&sbsec->isec_lock); 236 sbsec->magic = SELINUX_MAGIC; 237 sbsec->sb = sb; 238 sbsec->sid = SECINITSID_UNLABELED; 239 sbsec->def_sid = SECINITSID_FILE; 240 sb->s_security = sbsec; 241 242 return 0; 243 } 244 245 static void superblock_free_security(struct super_block *sb) 246 { 247 struct superblock_security_struct *sbsec = sb->s_security; 248 249 if (!sbsec || sbsec->magic != SELINUX_MAGIC) 250 return; 251 252 spin_lock(&sb_security_lock); 253 if (!list_empty(&sbsec->list)) 254 list_del_init(&sbsec->list); 255 spin_unlock(&sb_security_lock); 256 257 sb->s_security = NULL; 258 kfree(sbsec); 259 } 260 261 #ifdef CONFIG_SECURITY_NETWORK 262 static int sk_alloc_security(struct sock *sk, int family, gfp_t priority) 263 { 264 struct sk_security_struct *ssec; 265 266 if (family != PF_UNIX) 267 return 0; 268 269 ssec = kzalloc(sizeof(*ssec), priority); 270 if (!ssec) 271 return -ENOMEM; 272 273 ssec->magic = SELINUX_MAGIC; 274 ssec->sk = sk; 275 ssec->peer_sid = SECINITSID_UNLABELED; 276 sk->sk_security = ssec; 277 278 return 0; 279 } 280 281 static void sk_free_security(struct sock *sk) 282 { 283 struct sk_security_struct *ssec = sk->sk_security; 284 285 if (sk->sk_family != PF_UNIX || ssec->magic != SELINUX_MAGIC) 286 return; 287 288 sk->sk_security = NULL; 289 kfree(ssec); 290 } 291 #endif /* CONFIG_SECURITY_NETWORK */ 292 293 /* The security server must be initialized before 294 any labeling or access decisions can be provided. */ 295 extern int ss_initialized; 296 297 /* The file system's label must be initialized prior to use. */ 298 299 static char *labeling_behaviors[6] = { 300 "uses xattr", 301 "uses transition SIDs", 302 "uses task SIDs", 303 "uses genfs_contexts", 304 "not configured for labeling", 305 "uses mountpoint labeling", 306 }; 307 308 static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dentry); 309 310 static inline int inode_doinit(struct inode *inode) 311 { 312 return inode_doinit_with_dentry(inode, NULL); 313 } 314 315 enum { 316 Opt_context = 1, 317 Opt_fscontext = 2, 318 Opt_defcontext = 4, 319 }; 320 321 static match_table_t tokens = { 322 {Opt_context, "context=%s"}, 323 {Opt_fscontext, "fscontext=%s"}, 324 {Opt_defcontext, "defcontext=%s"}, 325 }; 326 327 #define SEL_MOUNT_FAIL_MSG "SELinux: duplicate or incompatible mount options\n" 328 329 static int try_context_mount(struct super_block *sb, void *data) 330 { 331 char *context = NULL, *defcontext = NULL; 332 const char *name; 333 u32 sid; 334 int alloc = 0, rc = 0, seen = 0; 335 struct task_security_struct *tsec = current->security; 336 struct superblock_security_struct *sbsec = sb->s_security; 337 338 if (!data) 339 goto out; 340 341 name = sb->s_type->name; 342 343 if (sb->s_type->fs_flags & FS_BINARY_MOUNTDATA) { 344 345 /* NFS we understand. */ 346 if (!strcmp(name, "nfs")) { 347 struct nfs_mount_data *d = data; 348 349 if (d->version < NFS_MOUNT_VERSION) 350 goto out; 351 352 if (d->context[0]) { 353 context = d->context; 354 seen |= Opt_context; 355 } 356 } else 357 goto out; 358 359 } else { 360 /* Standard string-based options. */ 361 char *p, *options = data; 362 363 while ((p = strsep(&options, ",")) != NULL) { 364 int token; 365 substring_t args[MAX_OPT_ARGS]; 366 367 if (!*p) 368 continue; 369 370 token = match_token(p, tokens, args); 371 372 switch (token) { 373 case Opt_context: 374 if (seen) { 375 rc = -EINVAL; 376 printk(KERN_WARNING SEL_MOUNT_FAIL_MSG); 377 goto out_free; 378 } 379 context = match_strdup(&args[0]); 380 if (!context) { 381 rc = -ENOMEM; 382 goto out_free; 383 } 384 if (!alloc) 385 alloc = 1; 386 seen |= Opt_context; 387 break; 388 389 case Opt_fscontext: 390 if (seen & (Opt_context|Opt_fscontext)) { 391 rc = -EINVAL; 392 printk(KERN_WARNING SEL_MOUNT_FAIL_MSG); 393 goto out_free; 394 } 395 context = match_strdup(&args[0]); 396 if (!context) { 397 rc = -ENOMEM; 398 goto out_free; 399 } 400 if (!alloc) 401 alloc = 1; 402 seen |= Opt_fscontext; 403 break; 404 405 case Opt_defcontext: 406 if (sbsec->behavior != SECURITY_FS_USE_XATTR) { 407 rc = -EINVAL; 408 printk(KERN_WARNING "SELinux: " 409 "defcontext option is invalid " 410 "for this filesystem type\n"); 411 goto out_free; 412 } 413 if (seen & (Opt_context|Opt_defcontext)) { 414 rc = -EINVAL; 415 printk(KERN_WARNING SEL_MOUNT_FAIL_MSG); 416 goto out_free; 417 } 418 defcontext = match_strdup(&args[0]); 419 if (!defcontext) { 420 rc = -ENOMEM; 421 goto out_free; 422 } 423 if (!alloc) 424 alloc = 1; 425 seen |= Opt_defcontext; 426 break; 427 428 default: 429 rc = -EINVAL; 430 printk(KERN_WARNING "SELinux: unknown mount " 431 "option\n"); 432 goto out_free; 433 434 } 435 } 436 } 437 438 if (!seen) 439 goto out; 440 441 if (context) { 442 rc = security_context_to_sid(context, strlen(context), &sid); 443 if (rc) { 444 printk(KERN_WARNING "SELinux: security_context_to_sid" 445 "(%s) failed for (dev %s, type %s) errno=%d\n", 446 context, sb->s_id, name, rc); 447 goto out_free; 448 } 449 450 rc = avc_has_perm(tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM, 451 FILESYSTEM__RELABELFROM, NULL); 452 if (rc) 453 goto out_free; 454 455 rc = avc_has_perm(tsec->sid, sid, SECCLASS_FILESYSTEM, 456 FILESYSTEM__RELABELTO, NULL); 457 if (rc) 458 goto out_free; 459 460 sbsec->sid = sid; 461 462 if (seen & Opt_context) 463 sbsec->behavior = SECURITY_FS_USE_MNTPOINT; 464 } 465 466 if (defcontext) { 467 rc = security_context_to_sid(defcontext, strlen(defcontext), &sid); 468 if (rc) { 469 printk(KERN_WARNING "SELinux: security_context_to_sid" 470 "(%s) failed for (dev %s, type %s) errno=%d\n", 471 defcontext, sb->s_id, name, rc); 472 goto out_free; 473 } 474 475 if (sid == sbsec->def_sid) 476 goto out_free; 477 478 rc = avc_has_perm(tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM, 479 FILESYSTEM__RELABELFROM, NULL); 480 if (rc) 481 goto out_free; 482 483 rc = avc_has_perm(sid, sbsec->sid, SECCLASS_FILESYSTEM, 484 FILESYSTEM__ASSOCIATE, NULL); 485 if (rc) 486 goto out_free; 487 488 sbsec->def_sid = sid; 489 } 490 491 out_free: 492 if (alloc) { 493 kfree(context); 494 kfree(defcontext); 495 } 496 out: 497 return rc; 498 } 499 500 static int superblock_doinit(struct super_block *sb, void *data) 501 { 502 struct superblock_security_struct *sbsec = sb->s_security; 503 struct dentry *root = sb->s_root; 504 struct inode *inode = root->d_inode; 505 int rc = 0; 506 507 down(&sbsec->sem); 508 if (sbsec->initialized) 509 goto out; 510 511 if (!ss_initialized) { 512 /* Defer initialization until selinux_complete_init, 513 after the initial policy is loaded and the security 514 server is ready to handle calls. */ 515 spin_lock(&sb_security_lock); 516 if (list_empty(&sbsec->list)) 517 list_add(&sbsec->list, &superblock_security_head); 518 spin_unlock(&sb_security_lock); 519 goto out; 520 } 521 522 /* Determine the labeling behavior to use for this filesystem type. */ 523 rc = security_fs_use(sb->s_type->name, &sbsec->behavior, &sbsec->sid); 524 if (rc) { 525 printk(KERN_WARNING "%s: security_fs_use(%s) returned %d\n", 526 __FUNCTION__, sb->s_type->name, rc); 527 goto out; 528 } 529 530 rc = try_context_mount(sb, data); 531 if (rc) 532 goto out; 533 534 if (sbsec->behavior == SECURITY_FS_USE_XATTR) { 535 /* Make sure that the xattr handler exists and that no 536 error other than -ENODATA is returned by getxattr on 537 the root directory. -ENODATA is ok, as this may be 538 the first boot of the SELinux kernel before we have 539 assigned xattr values to the filesystem. */ 540 if (!inode->i_op->getxattr) { 541 printk(KERN_WARNING "SELinux: (dev %s, type %s) has no " 542 "xattr support\n", sb->s_id, sb->s_type->name); 543 rc = -EOPNOTSUPP; 544 goto out; 545 } 546 rc = inode->i_op->getxattr(root, XATTR_NAME_SELINUX, NULL, 0); 547 if (rc < 0 && rc != -ENODATA) { 548 if (rc == -EOPNOTSUPP) 549 printk(KERN_WARNING "SELinux: (dev %s, type " 550 "%s) has no security xattr handler\n", 551 sb->s_id, sb->s_type->name); 552 else 553 printk(KERN_WARNING "SELinux: (dev %s, type " 554 "%s) getxattr errno %d\n", sb->s_id, 555 sb->s_type->name, -rc); 556 goto out; 557 } 558 } 559 560 if (strcmp(sb->s_type->name, "proc") == 0) 561 sbsec->proc = 1; 562 563 sbsec->initialized = 1; 564 565 if (sbsec->behavior > ARRAY_SIZE(labeling_behaviors)) { 566 printk(KERN_INFO "SELinux: initialized (dev %s, type %s), unknown behavior\n", 567 sb->s_id, sb->s_type->name); 568 } 569 else { 570 printk(KERN_INFO "SELinux: initialized (dev %s, type %s), %s\n", 571 sb->s_id, sb->s_type->name, 572 labeling_behaviors[sbsec->behavior-1]); 573 } 574 575 /* Initialize the root inode. */ 576 rc = inode_doinit_with_dentry(sb->s_root->d_inode, sb->s_root); 577 578 /* Initialize any other inodes associated with the superblock, e.g. 579 inodes created prior to initial policy load or inodes created 580 during get_sb by a pseudo filesystem that directly 581 populates itself. */ 582 spin_lock(&sbsec->isec_lock); 583 next_inode: 584 if (!list_empty(&sbsec->isec_head)) { 585 struct inode_security_struct *isec = 586 list_entry(sbsec->isec_head.next, 587 struct inode_security_struct, list); 588 struct inode *inode = isec->inode; 589 spin_unlock(&sbsec->isec_lock); 590 inode = igrab(inode); 591 if (inode) { 592 if (!IS_PRIVATE (inode)) 593 inode_doinit(inode); 594 iput(inode); 595 } 596 spin_lock(&sbsec->isec_lock); 597 list_del_init(&isec->list); 598 goto next_inode; 599 } 600 spin_unlock(&sbsec->isec_lock); 601 out: 602 up(&sbsec->sem); 603 return rc; 604 } 605 606 static inline u16 inode_mode_to_security_class(umode_t mode) 607 { 608 switch (mode & S_IFMT) { 609 case S_IFSOCK: 610 return SECCLASS_SOCK_FILE; 611 case S_IFLNK: 612 return SECCLASS_LNK_FILE; 613 case S_IFREG: 614 return SECCLASS_FILE; 615 case S_IFBLK: 616 return SECCLASS_BLK_FILE; 617 case S_IFDIR: 618 return SECCLASS_DIR; 619 case S_IFCHR: 620 return SECCLASS_CHR_FILE; 621 case S_IFIFO: 622 return SECCLASS_FIFO_FILE; 623 624 } 625 626 return SECCLASS_FILE; 627 } 628 629 static inline int default_protocol_stream(int protocol) 630 { 631 return (protocol == IPPROTO_IP || protocol == IPPROTO_TCP); 632 } 633 634 static inline int default_protocol_dgram(int protocol) 635 { 636 return (protocol == IPPROTO_IP || protocol == IPPROTO_UDP); 637 } 638 639 static inline u16 socket_type_to_security_class(int family, int type, int protocol) 640 { 641 switch (family) { 642 case PF_UNIX: 643 switch (type) { 644 case SOCK_STREAM: 645 case SOCK_SEQPACKET: 646 return SECCLASS_UNIX_STREAM_SOCKET; 647 case SOCK_DGRAM: 648 return SECCLASS_UNIX_DGRAM_SOCKET; 649 } 650 break; 651 case PF_INET: 652 case PF_INET6: 653 switch (type) { 654 case SOCK_STREAM: 655 if (default_protocol_stream(protocol)) 656 return SECCLASS_TCP_SOCKET; 657 else 658 return SECCLASS_RAWIP_SOCKET; 659 case SOCK_DGRAM: 660 if (default_protocol_dgram(protocol)) 661 return SECCLASS_UDP_SOCKET; 662 else 663 return SECCLASS_RAWIP_SOCKET; 664 default: 665 return SECCLASS_RAWIP_SOCKET; 666 } 667 break; 668 case PF_NETLINK: 669 switch (protocol) { 670 case NETLINK_ROUTE: 671 return SECCLASS_NETLINK_ROUTE_SOCKET; 672 case NETLINK_FIREWALL: 673 return SECCLASS_NETLINK_FIREWALL_SOCKET; 674 case NETLINK_INET_DIAG: 675 return SECCLASS_NETLINK_TCPDIAG_SOCKET; 676 case NETLINK_NFLOG: 677 return SECCLASS_NETLINK_NFLOG_SOCKET; 678 case NETLINK_XFRM: 679 return SECCLASS_NETLINK_XFRM_SOCKET; 680 case NETLINK_SELINUX: 681 return SECCLASS_NETLINK_SELINUX_SOCKET; 682 case NETLINK_AUDIT: 683 return SECCLASS_NETLINK_AUDIT_SOCKET; 684 case NETLINK_IP6_FW: 685 return SECCLASS_NETLINK_IP6FW_SOCKET; 686 case NETLINK_DNRTMSG: 687 return SECCLASS_NETLINK_DNRT_SOCKET; 688 case NETLINK_KOBJECT_UEVENT: 689 return SECCLASS_NETLINK_KOBJECT_UEVENT_SOCKET; 690 default: 691 return SECCLASS_NETLINK_SOCKET; 692 } 693 case PF_PACKET: 694 return SECCLASS_PACKET_SOCKET; 695 case PF_KEY: 696 return SECCLASS_KEY_SOCKET; 697 } 698 699 return SECCLASS_SOCKET; 700 } 701 702 #ifdef CONFIG_PROC_FS 703 static int selinux_proc_get_sid(struct proc_dir_entry *de, 704 u16 tclass, 705 u32 *sid) 706 { 707 int buflen, rc; 708 char *buffer, *path, *end; 709 710 buffer = (char*)__get_free_page(GFP_KERNEL); 711 if (!buffer) 712 return -ENOMEM; 713 714 buflen = PAGE_SIZE; 715 end = buffer+buflen; 716 *--end = '\0'; 717 buflen--; 718 path = end-1; 719 *path = '/'; 720 while (de && de != de->parent) { 721 buflen -= de->namelen + 1; 722 if (buflen < 0) 723 break; 724 end -= de->namelen; 725 memcpy(end, de->name, de->namelen); 726 *--end = '/'; 727 path = end; 728 de = de->parent; 729 } 730 rc = security_genfs_sid("proc", path, tclass, sid); 731 free_page((unsigned long)buffer); 732 return rc; 733 } 734 #else 735 static int selinux_proc_get_sid(struct proc_dir_entry *de, 736 u16 tclass, 737 u32 *sid) 738 { 739 return -EINVAL; 740 } 741 #endif 742 743 /* The inode's security attributes must be initialized before first use. */ 744 static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dentry) 745 { 746 struct superblock_security_struct *sbsec = NULL; 747 struct inode_security_struct *isec = inode->i_security; 748 u32 sid; 749 struct dentry *dentry; 750 #define INITCONTEXTLEN 255 751 char *context = NULL; 752 unsigned len = 0; 753 int rc = 0; 754 int hold_sem = 0; 755 756 if (isec->initialized) 757 goto out; 758 759 down(&isec->sem); 760 hold_sem = 1; 761 if (isec->initialized) 762 goto out; 763 764 sbsec = inode->i_sb->s_security; 765 if (!sbsec->initialized) { 766 /* Defer initialization until selinux_complete_init, 767 after the initial policy is loaded and the security 768 server is ready to handle calls. */ 769 spin_lock(&sbsec->isec_lock); 770 if (list_empty(&isec->list)) 771 list_add(&isec->list, &sbsec->isec_head); 772 spin_unlock(&sbsec->isec_lock); 773 goto out; 774 } 775 776 switch (sbsec->behavior) { 777 case SECURITY_FS_USE_XATTR: 778 if (!inode->i_op->getxattr) { 779 isec->sid = sbsec->def_sid; 780 break; 781 } 782 783 /* Need a dentry, since the xattr API requires one. 784 Life would be simpler if we could just pass the inode. */ 785 if (opt_dentry) { 786 /* Called from d_instantiate or d_splice_alias. */ 787 dentry = dget(opt_dentry); 788 } else { 789 /* Called from selinux_complete_init, try to find a dentry. */ 790 dentry = d_find_alias(inode); 791 } 792 if (!dentry) { 793 printk(KERN_WARNING "%s: no dentry for dev=%s " 794 "ino=%ld\n", __FUNCTION__, inode->i_sb->s_id, 795 inode->i_ino); 796 goto out; 797 } 798 799 len = INITCONTEXTLEN; 800 context = kmalloc(len, GFP_KERNEL); 801 if (!context) { 802 rc = -ENOMEM; 803 dput(dentry); 804 goto out; 805 } 806 rc = inode->i_op->getxattr(dentry, XATTR_NAME_SELINUX, 807 context, len); 808 if (rc == -ERANGE) { 809 /* Need a larger buffer. Query for the right size. */ 810 rc = inode->i_op->getxattr(dentry, XATTR_NAME_SELINUX, 811 NULL, 0); 812 if (rc < 0) { 813 dput(dentry); 814 goto out; 815 } 816 kfree(context); 817 len = rc; 818 context = kmalloc(len, GFP_KERNEL); 819 if (!context) { 820 rc = -ENOMEM; 821 dput(dentry); 822 goto out; 823 } 824 rc = inode->i_op->getxattr(dentry, 825 XATTR_NAME_SELINUX, 826 context, len); 827 } 828 dput(dentry); 829 if (rc < 0) { 830 if (rc != -ENODATA) { 831 printk(KERN_WARNING "%s: getxattr returned " 832 "%d for dev=%s ino=%ld\n", __FUNCTION__, 833 -rc, inode->i_sb->s_id, inode->i_ino); 834 kfree(context); 835 goto out; 836 } 837 /* Map ENODATA to the default file SID */ 838 sid = sbsec->def_sid; 839 rc = 0; 840 } else { 841 rc = security_context_to_sid_default(context, rc, &sid, 842 sbsec->def_sid); 843 if (rc) { 844 printk(KERN_WARNING "%s: context_to_sid(%s) " 845 "returned %d for dev=%s ino=%ld\n", 846 __FUNCTION__, context, -rc, 847 inode->i_sb->s_id, inode->i_ino); 848 kfree(context); 849 /* Leave with the unlabeled SID */ 850 rc = 0; 851 break; 852 } 853 } 854 kfree(context); 855 isec->sid = sid; 856 break; 857 case SECURITY_FS_USE_TASK: 858 isec->sid = isec->task_sid; 859 break; 860 case SECURITY_FS_USE_TRANS: 861 /* Default to the fs SID. */ 862 isec->sid = sbsec->sid; 863 864 /* Try to obtain a transition SID. */ 865 isec->sclass = inode_mode_to_security_class(inode->i_mode); 866 rc = security_transition_sid(isec->task_sid, 867 sbsec->sid, 868 isec->sclass, 869 &sid); 870 if (rc) 871 goto out; 872 isec->sid = sid; 873 break; 874 default: 875 /* Default to the fs SID. */ 876 isec->sid = sbsec->sid; 877 878 if (sbsec->proc) { 879 struct proc_inode *proci = PROC_I(inode); 880 if (proci->pde) { 881 isec->sclass = inode_mode_to_security_class(inode->i_mode); 882 rc = selinux_proc_get_sid(proci->pde, 883 isec->sclass, 884 &sid); 885 if (rc) 886 goto out; 887 isec->sid = sid; 888 } 889 } 890 break; 891 } 892 893 isec->initialized = 1; 894 895 out: 896 if (isec->sclass == SECCLASS_FILE) 897 isec->sclass = inode_mode_to_security_class(inode->i_mode); 898 899 if (hold_sem) 900 up(&isec->sem); 901 return rc; 902 } 903 904 /* Convert a Linux signal to an access vector. */ 905 static inline u32 signal_to_av(int sig) 906 { 907 u32 perm = 0; 908 909 switch (sig) { 910 case SIGCHLD: 911 /* Commonly granted from child to parent. */ 912 perm = PROCESS__SIGCHLD; 913 break; 914 case SIGKILL: 915 /* Cannot be caught or ignored */ 916 perm = PROCESS__SIGKILL; 917 break; 918 case SIGSTOP: 919 /* Cannot be caught or ignored */ 920 perm = PROCESS__SIGSTOP; 921 break; 922 default: 923 /* All other signals. */ 924 perm = PROCESS__SIGNAL; 925 break; 926 } 927 928 return perm; 929 } 930 931 /* Check permission betweeen a pair of tasks, e.g. signal checks, 932 fork check, ptrace check, etc. */ 933 static int task_has_perm(struct task_struct *tsk1, 934 struct task_struct *tsk2, 935 u32 perms) 936 { 937 struct task_security_struct *tsec1, *tsec2; 938 939 tsec1 = tsk1->security; 940 tsec2 = tsk2->security; 941 return avc_has_perm(tsec1->sid, tsec2->sid, 942 SECCLASS_PROCESS, perms, NULL); 943 } 944 945 /* Check whether a task is allowed to use a capability. */ 946 static int task_has_capability(struct task_struct *tsk, 947 int cap) 948 { 949 struct task_security_struct *tsec; 950 struct avc_audit_data ad; 951 952 tsec = tsk->security; 953 954 AVC_AUDIT_DATA_INIT(&ad,CAP); 955 ad.tsk = tsk; 956 ad.u.cap = cap; 957 958 return avc_has_perm(tsec->sid, tsec->sid, 959 SECCLASS_CAPABILITY, CAP_TO_MASK(cap), &ad); 960 } 961 962 /* Check whether a task is allowed to use a system operation. */ 963 static int task_has_system(struct task_struct *tsk, 964 u32 perms) 965 { 966 struct task_security_struct *tsec; 967 968 tsec = tsk->security; 969 970 return avc_has_perm(tsec->sid, SECINITSID_KERNEL, 971 SECCLASS_SYSTEM, perms, NULL); 972 } 973 974 /* Check whether a task has a particular permission to an inode. 975 The 'adp' parameter is optional and allows other audit 976 data to be passed (e.g. the dentry). */ 977 static int inode_has_perm(struct task_struct *tsk, 978 struct inode *inode, 979 u32 perms, 980 struct avc_audit_data *adp) 981 { 982 struct task_security_struct *tsec; 983 struct inode_security_struct *isec; 984 struct avc_audit_data ad; 985 986 tsec = tsk->security; 987 isec = inode->i_security; 988 989 if (!adp) { 990 adp = &ad; 991 AVC_AUDIT_DATA_INIT(&ad, FS); 992 ad.u.fs.inode = inode; 993 } 994 995 return avc_has_perm(tsec->sid, isec->sid, isec->sclass, perms, adp); 996 } 997 998 /* Same as inode_has_perm, but pass explicit audit data containing 999 the dentry to help the auditing code to more easily generate the 1000 pathname if needed. */ 1001 static inline int dentry_has_perm(struct task_struct *tsk, 1002 struct vfsmount *mnt, 1003 struct dentry *dentry, 1004 u32 av) 1005 { 1006 struct inode *inode = dentry->d_inode; 1007 struct avc_audit_data ad; 1008 AVC_AUDIT_DATA_INIT(&ad,FS); 1009 ad.u.fs.mnt = mnt; 1010 ad.u.fs.dentry = dentry; 1011 return inode_has_perm(tsk, inode, av, &ad); 1012 } 1013 1014 /* Check whether a task can use an open file descriptor to 1015 access an inode in a given way. Check access to the 1016 descriptor itself, and then use dentry_has_perm to 1017 check a particular permission to the file. 1018 Access to the descriptor is implicitly granted if it 1019 has the same SID as the process. If av is zero, then 1020 access to the file is not checked, e.g. for cases 1021 where only the descriptor is affected like seek. */ 1022 static inline int file_has_perm(struct task_struct *tsk, 1023 struct file *file, 1024 u32 av) 1025 { 1026 struct task_security_struct *tsec = tsk->security; 1027 struct file_security_struct *fsec = file->f_security; 1028 struct vfsmount *mnt = file->f_vfsmnt; 1029 struct dentry *dentry = file->f_dentry; 1030 struct inode *inode = dentry->d_inode; 1031 struct avc_audit_data ad; 1032 int rc; 1033 1034 AVC_AUDIT_DATA_INIT(&ad, FS); 1035 ad.u.fs.mnt = mnt; 1036 ad.u.fs.dentry = dentry; 1037 1038 if (tsec->sid != fsec->sid) { 1039 rc = avc_has_perm(tsec->sid, fsec->sid, 1040 SECCLASS_FD, 1041 FD__USE, 1042 &ad); 1043 if (rc) 1044 return rc; 1045 } 1046 1047 /* av is zero if only checking access to the descriptor. */ 1048 if (av) 1049 return inode_has_perm(tsk, inode, av, &ad); 1050 1051 return 0; 1052 } 1053 1054 /* Check whether a task can create a file. */ 1055 static int may_create(struct inode *dir, 1056 struct dentry *dentry, 1057 u16 tclass) 1058 { 1059 struct task_security_struct *tsec; 1060 struct inode_security_struct *dsec; 1061 struct superblock_security_struct *sbsec; 1062 u32 newsid; 1063 struct avc_audit_data ad; 1064 int rc; 1065 1066 tsec = current->security; 1067 dsec = dir->i_security; 1068 sbsec = dir->i_sb->s_security; 1069 1070 AVC_AUDIT_DATA_INIT(&ad, FS); 1071 ad.u.fs.dentry = dentry; 1072 1073 rc = avc_has_perm(tsec->sid, dsec->sid, SECCLASS_DIR, 1074 DIR__ADD_NAME | DIR__SEARCH, 1075 &ad); 1076 if (rc) 1077 return rc; 1078 1079 if (tsec->create_sid && sbsec->behavior != SECURITY_FS_USE_MNTPOINT) { 1080 newsid = tsec->create_sid; 1081 } else { 1082 rc = security_transition_sid(tsec->sid, dsec->sid, tclass, 1083 &newsid); 1084 if (rc) 1085 return rc; 1086 } 1087 1088 rc = avc_has_perm(tsec->sid, newsid, tclass, FILE__CREATE, &ad); 1089 if (rc) 1090 return rc; 1091 1092 return avc_has_perm(newsid, sbsec->sid, 1093 SECCLASS_FILESYSTEM, 1094 FILESYSTEM__ASSOCIATE, &ad); 1095 } 1096 1097 #define MAY_LINK 0 1098 #define MAY_UNLINK 1 1099 #define MAY_RMDIR 2 1100 1101 /* Check whether a task can link, unlink, or rmdir a file/directory. */ 1102 static int may_link(struct inode *dir, 1103 struct dentry *dentry, 1104 int kind) 1105 1106 { 1107 struct task_security_struct *tsec; 1108 struct inode_security_struct *dsec, *isec; 1109 struct avc_audit_data ad; 1110 u32 av; 1111 int rc; 1112 1113 tsec = current->security; 1114 dsec = dir->i_security; 1115 isec = dentry->d_inode->i_security; 1116 1117 AVC_AUDIT_DATA_INIT(&ad, FS); 1118 ad.u.fs.dentry = dentry; 1119 1120 av = DIR__SEARCH; 1121 av |= (kind ? DIR__REMOVE_NAME : DIR__ADD_NAME); 1122 rc = avc_has_perm(tsec->sid, dsec->sid, SECCLASS_DIR, av, &ad); 1123 if (rc) 1124 return rc; 1125 1126 switch (kind) { 1127 case MAY_LINK: 1128 av = FILE__LINK; 1129 break; 1130 case MAY_UNLINK: 1131 av = FILE__UNLINK; 1132 break; 1133 case MAY_RMDIR: 1134 av = DIR__RMDIR; 1135 break; 1136 default: 1137 printk(KERN_WARNING "may_link: unrecognized kind %d\n", kind); 1138 return 0; 1139 } 1140 1141 rc = avc_has_perm(tsec->sid, isec->sid, isec->sclass, av, &ad); 1142 return rc; 1143 } 1144 1145 static inline int may_rename(struct inode *old_dir, 1146 struct dentry *old_dentry, 1147 struct inode *new_dir, 1148 struct dentry *new_dentry) 1149 { 1150 struct task_security_struct *tsec; 1151 struct inode_security_struct *old_dsec, *new_dsec, *old_isec, *new_isec; 1152 struct avc_audit_data ad; 1153 u32 av; 1154 int old_is_dir, new_is_dir; 1155 int rc; 1156 1157 tsec = current->security; 1158 old_dsec = old_dir->i_security; 1159 old_isec = old_dentry->d_inode->i_security; 1160 old_is_dir = S_ISDIR(old_dentry->d_inode->i_mode); 1161 new_dsec = new_dir->i_security; 1162 1163 AVC_AUDIT_DATA_INIT(&ad, FS); 1164 1165 ad.u.fs.dentry = old_dentry; 1166 rc = avc_has_perm(tsec->sid, old_dsec->sid, SECCLASS_DIR, 1167 DIR__REMOVE_NAME | DIR__SEARCH, &ad); 1168 if (rc) 1169 return rc; 1170 rc = avc_has_perm(tsec->sid, old_isec->sid, 1171 old_isec->sclass, FILE__RENAME, &ad); 1172 if (rc) 1173 return rc; 1174 if (old_is_dir && new_dir != old_dir) { 1175 rc = avc_has_perm(tsec->sid, old_isec->sid, 1176 old_isec->sclass, DIR__REPARENT, &ad); 1177 if (rc) 1178 return rc; 1179 } 1180 1181 ad.u.fs.dentry = new_dentry; 1182 av = DIR__ADD_NAME | DIR__SEARCH; 1183 if (new_dentry->d_inode) 1184 av |= DIR__REMOVE_NAME; 1185 rc = avc_has_perm(tsec->sid, new_dsec->sid, SECCLASS_DIR, av, &ad); 1186 if (rc) 1187 return rc; 1188 if (new_dentry->d_inode) { 1189 new_isec = new_dentry->d_inode->i_security; 1190 new_is_dir = S_ISDIR(new_dentry->d_inode->i_mode); 1191 rc = avc_has_perm(tsec->sid, new_isec->sid, 1192 new_isec->sclass, 1193 (new_is_dir ? DIR__RMDIR : FILE__UNLINK), &ad); 1194 if (rc) 1195 return rc; 1196 } 1197 1198 return 0; 1199 } 1200 1201 /* Check whether a task can perform a filesystem operation. */ 1202 static int superblock_has_perm(struct task_struct *tsk, 1203 struct super_block *sb, 1204 u32 perms, 1205 struct avc_audit_data *ad) 1206 { 1207 struct task_security_struct *tsec; 1208 struct superblock_security_struct *sbsec; 1209 1210 tsec = tsk->security; 1211 sbsec = sb->s_security; 1212 return avc_has_perm(tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM, 1213 perms, ad); 1214 } 1215 1216 /* Convert a Linux mode and permission mask to an access vector. */ 1217 static inline u32 file_mask_to_av(int mode, int mask) 1218 { 1219 u32 av = 0; 1220 1221 if ((mode & S_IFMT) != S_IFDIR) { 1222 if (mask & MAY_EXEC) 1223 av |= FILE__EXECUTE; 1224 if (mask & MAY_READ) 1225 av |= FILE__READ; 1226 1227 if (mask & MAY_APPEND) 1228 av |= FILE__APPEND; 1229 else if (mask & MAY_WRITE) 1230 av |= FILE__WRITE; 1231 1232 } else { 1233 if (mask & MAY_EXEC) 1234 av |= DIR__SEARCH; 1235 if (mask & MAY_WRITE) 1236 av |= DIR__WRITE; 1237 if (mask & MAY_READ) 1238 av |= DIR__READ; 1239 } 1240 1241 return av; 1242 } 1243 1244 /* Convert a Linux file to an access vector. */ 1245 static inline u32 file_to_av(struct file *file) 1246 { 1247 u32 av = 0; 1248 1249 if (file->f_mode & FMODE_READ) 1250 av |= FILE__READ; 1251 if (file->f_mode & FMODE_WRITE) { 1252 if (file->f_flags & O_APPEND) 1253 av |= FILE__APPEND; 1254 else 1255 av |= FILE__WRITE; 1256 } 1257 1258 return av; 1259 } 1260 1261 /* Set an inode's SID to a specified value. */ 1262 static int inode_security_set_sid(struct inode *inode, u32 sid) 1263 { 1264 struct inode_security_struct *isec = inode->i_security; 1265 struct superblock_security_struct *sbsec = inode->i_sb->s_security; 1266 1267 if (!sbsec->initialized) { 1268 /* Defer initialization to selinux_complete_init. */ 1269 return 0; 1270 } 1271 1272 down(&isec->sem); 1273 isec->sclass = inode_mode_to_security_class(inode->i_mode); 1274 isec->sid = sid; 1275 isec->initialized = 1; 1276 up(&isec->sem); 1277 return 0; 1278 } 1279 1280 /* Hook functions begin here. */ 1281 1282 static int selinux_ptrace(struct task_struct *parent, struct task_struct *child) 1283 { 1284 struct task_security_struct *psec = parent->security; 1285 struct task_security_struct *csec = child->security; 1286 int rc; 1287 1288 rc = secondary_ops->ptrace(parent,child); 1289 if (rc) 1290 return rc; 1291 1292 rc = task_has_perm(parent, child, PROCESS__PTRACE); 1293 /* Save the SID of the tracing process for later use in apply_creds. */ 1294 if (!rc) 1295 csec->ptrace_sid = psec->sid; 1296 return rc; 1297 } 1298 1299 static int selinux_capget(struct task_struct *target, kernel_cap_t *effective, 1300 kernel_cap_t *inheritable, kernel_cap_t *permitted) 1301 { 1302 int error; 1303 1304 error = task_has_perm(current, target, PROCESS__GETCAP); 1305 if (error) 1306 return error; 1307 1308 return secondary_ops->capget(target, effective, inheritable, permitted); 1309 } 1310 1311 static int selinux_capset_check(struct task_struct *target, kernel_cap_t *effective, 1312 kernel_cap_t *inheritable, kernel_cap_t *permitted) 1313 { 1314 int error; 1315 1316 error = secondary_ops->capset_check(target, effective, inheritable, permitted); 1317 if (error) 1318 return error; 1319 1320 return task_has_perm(current, target, PROCESS__SETCAP); 1321 } 1322 1323 static void selinux_capset_set(struct task_struct *target, kernel_cap_t *effective, 1324 kernel_cap_t *inheritable, kernel_cap_t *permitted) 1325 { 1326 secondary_ops->capset_set(target, effective, inheritable, permitted); 1327 } 1328 1329 static int selinux_capable(struct task_struct *tsk, int cap) 1330 { 1331 int rc; 1332 1333 rc = secondary_ops->capable(tsk, cap); 1334 if (rc) 1335 return rc; 1336 1337 return task_has_capability(tsk,cap); 1338 } 1339 1340 static int selinux_sysctl(ctl_table *table, int op) 1341 { 1342 int error = 0; 1343 u32 av; 1344 struct task_security_struct *tsec; 1345 u32 tsid; 1346 int rc; 1347 1348 rc = secondary_ops->sysctl(table, op); 1349 if (rc) 1350 return rc; 1351 1352 tsec = current->security; 1353 1354 rc = selinux_proc_get_sid(table->de, (op == 001) ? 1355 SECCLASS_DIR : SECCLASS_FILE, &tsid); 1356 if (rc) { 1357 /* Default to the well-defined sysctl SID. */ 1358 tsid = SECINITSID_SYSCTL; 1359 } 1360 1361 /* The op values are "defined" in sysctl.c, thereby creating 1362 * a bad coupling between this module and sysctl.c */ 1363 if(op == 001) { 1364 error = avc_has_perm(tsec->sid, tsid, 1365 SECCLASS_DIR, DIR__SEARCH, NULL); 1366 } else { 1367 av = 0; 1368 if (op & 004) 1369 av |= FILE__READ; 1370 if (op & 002) 1371 av |= FILE__WRITE; 1372 if (av) 1373 error = avc_has_perm(tsec->sid, tsid, 1374 SECCLASS_FILE, av, NULL); 1375 } 1376 1377 return error; 1378 } 1379 1380 static int selinux_quotactl(int cmds, int type, int id, struct super_block *sb) 1381 { 1382 int rc = 0; 1383 1384 if (!sb) 1385 return 0; 1386 1387 switch (cmds) { 1388 case Q_SYNC: 1389 case Q_QUOTAON: 1390 case Q_QUOTAOFF: 1391 case Q_SETINFO: 1392 case Q_SETQUOTA: 1393 rc = superblock_has_perm(current, 1394 sb, 1395 FILESYSTEM__QUOTAMOD, NULL); 1396 break; 1397 case Q_GETFMT: 1398 case Q_GETINFO: 1399 case Q_GETQUOTA: 1400 rc = superblock_has_perm(current, 1401 sb, 1402 FILESYSTEM__QUOTAGET, NULL); 1403 break; 1404 default: 1405 rc = 0; /* let the kernel handle invalid cmds */ 1406 break; 1407 } 1408 return rc; 1409 } 1410 1411 static int selinux_quota_on(struct dentry *dentry) 1412 { 1413 return dentry_has_perm(current, NULL, dentry, FILE__QUOTAON); 1414 } 1415 1416 static int selinux_syslog(int type) 1417 { 1418 int rc; 1419 1420 rc = secondary_ops->syslog(type); 1421 if (rc) 1422 return rc; 1423 1424 switch (type) { 1425 case 3: /* Read last kernel messages */ 1426 case 10: /* Return size of the log buffer */ 1427 rc = task_has_system(current, SYSTEM__SYSLOG_READ); 1428 break; 1429 case 6: /* Disable logging to console */ 1430 case 7: /* Enable logging to console */ 1431 case 8: /* Set level of messages printed to console */ 1432 rc = task_has_system(current, SYSTEM__SYSLOG_CONSOLE); 1433 break; 1434 case 0: /* Close log */ 1435 case 1: /* Open log */ 1436 case 2: /* Read from log */ 1437 case 4: /* Read/clear last kernel messages */ 1438 case 5: /* Clear ring buffer */ 1439 default: 1440 rc = task_has_system(current, SYSTEM__SYSLOG_MOD); 1441 break; 1442 } 1443 return rc; 1444 } 1445 1446 /* 1447 * Check that a process has enough memory to allocate a new virtual 1448 * mapping. 0 means there is enough memory for the allocation to 1449 * succeed and -ENOMEM implies there is not. 1450 * 1451 * Note that secondary_ops->capable and task_has_perm_noaudit return 0 1452 * if the capability is granted, but __vm_enough_memory requires 1 if 1453 * the capability is granted. 1454 * 1455 * Do not audit the selinux permission check, as this is applied to all 1456 * processes that allocate mappings. 1457 */ 1458 static int selinux_vm_enough_memory(long pages) 1459 { 1460 int rc, cap_sys_admin = 0; 1461 struct task_security_struct *tsec = current->security; 1462 1463 rc = secondary_ops->capable(current, CAP_SYS_ADMIN); 1464 if (rc == 0) 1465 rc = avc_has_perm_noaudit(tsec->sid, tsec->sid, 1466 SECCLASS_CAPABILITY, 1467 CAP_TO_MASK(CAP_SYS_ADMIN), 1468 NULL); 1469 1470 if (rc == 0) 1471 cap_sys_admin = 1; 1472 1473 return __vm_enough_memory(pages, cap_sys_admin); 1474 } 1475 1476 /* binprm security operations */ 1477 1478 static int selinux_bprm_alloc_security(struct linux_binprm *bprm) 1479 { 1480 struct bprm_security_struct *bsec; 1481 1482 bsec = kzalloc(sizeof(struct bprm_security_struct), GFP_KERNEL); 1483 if (!bsec) 1484 return -ENOMEM; 1485 1486 bsec->magic = SELINUX_MAGIC; 1487 bsec->bprm = bprm; 1488 bsec->sid = SECINITSID_UNLABELED; 1489 bsec->set = 0; 1490 1491 bprm->security = bsec; 1492 return 0; 1493 } 1494 1495 static int selinux_bprm_set_security(struct linux_binprm *bprm) 1496 { 1497 struct task_security_struct *tsec; 1498 struct inode *inode = bprm->file->f_dentry->d_inode; 1499 struct inode_security_struct *isec; 1500 struct bprm_security_struct *bsec; 1501 u32 newsid; 1502 struct avc_audit_data ad; 1503 int rc; 1504 1505 rc = secondary_ops->bprm_set_security(bprm); 1506 if (rc) 1507 return rc; 1508 1509 bsec = bprm->security; 1510 1511 if (bsec->set) 1512 return 0; 1513 1514 tsec = current->security; 1515 isec = inode->i_security; 1516 1517 /* Default to the current task SID. */ 1518 bsec->sid = tsec->sid; 1519 1520 /* Reset create SID on execve. */ 1521 tsec->create_sid = 0; 1522 1523 if (tsec->exec_sid) { 1524 newsid = tsec->exec_sid; 1525 /* Reset exec SID on execve. */ 1526 tsec->exec_sid = 0; 1527 } else { 1528 /* Check for a default transition on this program. */ 1529 rc = security_transition_sid(tsec->sid, isec->sid, 1530 SECCLASS_PROCESS, &newsid); 1531 if (rc) 1532 return rc; 1533 } 1534 1535 AVC_AUDIT_DATA_INIT(&ad, FS); 1536 ad.u.fs.mnt = bprm->file->f_vfsmnt; 1537 ad.u.fs.dentry = bprm->file->f_dentry; 1538 1539 if (bprm->file->f_vfsmnt->mnt_flags & MNT_NOSUID) 1540 newsid = tsec->sid; 1541 1542 if (tsec->sid == newsid) { 1543 rc = avc_has_perm(tsec->sid, isec->sid, 1544 SECCLASS_FILE, FILE__EXECUTE_NO_TRANS, &ad); 1545 if (rc) 1546 return rc; 1547 } else { 1548 /* Check permissions for the transition. */ 1549 rc = avc_has_perm(tsec->sid, newsid, 1550 SECCLASS_PROCESS, PROCESS__TRANSITION, &ad); 1551 if (rc) 1552 return rc; 1553 1554 rc = avc_has_perm(newsid, isec->sid, 1555 SECCLASS_FILE, FILE__ENTRYPOINT, &ad); 1556 if (rc) 1557 return rc; 1558 1559 /* Clear any possibly unsafe personality bits on exec: */ 1560 current->personality &= ~PER_CLEAR_ON_SETID; 1561 1562 /* Set the security field to the new SID. */ 1563 bsec->sid = newsid; 1564 } 1565 1566 bsec->set = 1; 1567 return 0; 1568 } 1569 1570 static int selinux_bprm_check_security (struct linux_binprm *bprm) 1571 { 1572 return secondary_ops->bprm_check_security(bprm); 1573 } 1574 1575 1576 static int selinux_bprm_secureexec (struct linux_binprm *bprm) 1577 { 1578 struct task_security_struct *tsec = current->security; 1579 int atsecure = 0; 1580 1581 if (tsec->osid != tsec->sid) { 1582 /* Enable secure mode for SIDs transitions unless 1583 the noatsecure permission is granted between 1584 the two SIDs, i.e. ahp returns 0. */ 1585 atsecure = avc_has_perm(tsec->osid, tsec->sid, 1586 SECCLASS_PROCESS, 1587 PROCESS__NOATSECURE, NULL); 1588 } 1589 1590 return (atsecure || secondary_ops->bprm_secureexec(bprm)); 1591 } 1592 1593 static void selinux_bprm_free_security(struct linux_binprm *bprm) 1594 { 1595 kfree(bprm->security); 1596 bprm->security = NULL; 1597 } 1598 1599 extern struct vfsmount *selinuxfs_mount; 1600 extern struct dentry *selinux_null; 1601 1602 /* Derived from fs/exec.c:flush_old_files. */ 1603 static inline void flush_unauthorized_files(struct files_struct * files) 1604 { 1605 struct avc_audit_data ad; 1606 struct file *file, *devnull = NULL; 1607 struct tty_struct *tty = current->signal->tty; 1608 struct fdtable *fdt; 1609 long j = -1; 1610 1611 if (tty) { 1612 file_list_lock(); 1613 file = list_entry(tty->tty_files.next, typeof(*file), f_u.fu_list); 1614 if (file) { 1615 /* Revalidate access to controlling tty. 1616 Use inode_has_perm on the tty inode directly rather 1617 than using file_has_perm, as this particular open 1618 file may belong to another process and we are only 1619 interested in the inode-based check here. */ 1620 struct inode *inode = file->f_dentry->d_inode; 1621 if (inode_has_perm(current, inode, 1622 FILE__READ | FILE__WRITE, NULL)) { 1623 /* Reset controlling tty. */ 1624 current->signal->tty = NULL; 1625 current->signal->tty_old_pgrp = 0; 1626 } 1627 } 1628 file_list_unlock(); 1629 } 1630 1631 /* Revalidate access to inherited open files. */ 1632 1633 AVC_AUDIT_DATA_INIT(&ad,FS); 1634 1635 spin_lock(&files->file_lock); 1636 for (;;) { 1637 unsigned long set, i; 1638 int fd; 1639 1640 j++; 1641 i = j * __NFDBITS; 1642 fdt = files_fdtable(files); 1643 if (i >= fdt->max_fds || i >= fdt->max_fdset) 1644 break; 1645 set = fdt->open_fds->fds_bits[j]; 1646 if (!set) 1647 continue; 1648 spin_unlock(&files->file_lock); 1649 for ( ; set ; i++,set >>= 1) { 1650 if (set & 1) { 1651 file = fget(i); 1652 if (!file) 1653 continue; 1654 if (file_has_perm(current, 1655 file, 1656 file_to_av(file))) { 1657 sys_close(i); 1658 fd = get_unused_fd(); 1659 if (fd != i) { 1660 if (fd >= 0) 1661 put_unused_fd(fd); 1662 fput(file); 1663 continue; 1664 } 1665 if (devnull) { 1666 get_file(devnull); 1667 } else { 1668 devnull = dentry_open(dget(selinux_null), mntget(selinuxfs_mount), O_RDWR); 1669 if (!devnull) { 1670 put_unused_fd(fd); 1671 fput(file); 1672 continue; 1673 } 1674 } 1675 fd_install(fd, devnull); 1676 } 1677 fput(file); 1678 } 1679 } 1680 spin_lock(&files->file_lock); 1681 1682 } 1683 spin_unlock(&files->file_lock); 1684 } 1685 1686 static void selinux_bprm_apply_creds(struct linux_binprm *bprm, int unsafe) 1687 { 1688 struct task_security_struct *tsec; 1689 struct bprm_security_struct *bsec; 1690 u32 sid; 1691 int rc; 1692 1693 secondary_ops->bprm_apply_creds(bprm, unsafe); 1694 1695 tsec = current->security; 1696 1697 bsec = bprm->security; 1698 sid = bsec->sid; 1699 1700 tsec->osid = tsec->sid; 1701 bsec->unsafe = 0; 1702 if (tsec->sid != sid) { 1703 /* Check for shared state. If not ok, leave SID 1704 unchanged and kill. */ 1705 if (unsafe & LSM_UNSAFE_SHARE) { 1706 rc = avc_has_perm(tsec->sid, sid, SECCLASS_PROCESS, 1707 PROCESS__SHARE, NULL); 1708 if (rc) { 1709 bsec->unsafe = 1; 1710 return; 1711 } 1712 } 1713 1714 /* Check for ptracing, and update the task SID if ok. 1715 Otherwise, leave SID unchanged and kill. */ 1716 if (unsafe & (LSM_UNSAFE_PTRACE | LSM_UNSAFE_PTRACE_CAP)) { 1717 rc = avc_has_perm(tsec->ptrace_sid, sid, 1718 SECCLASS_PROCESS, PROCESS__PTRACE, 1719 NULL); 1720 if (rc) { 1721 bsec->unsafe = 1; 1722 return; 1723 } 1724 } 1725 tsec->sid = sid; 1726 } 1727 } 1728 1729 /* 1730 * called after apply_creds without the task lock held 1731 */ 1732 static void selinux_bprm_post_apply_creds(struct linux_binprm *bprm) 1733 { 1734 struct task_security_struct *tsec; 1735 struct rlimit *rlim, *initrlim; 1736 struct itimerval itimer; 1737 struct bprm_security_struct *bsec; 1738 int rc, i; 1739 1740 tsec = current->security; 1741 bsec = bprm->security; 1742 1743 if (bsec->unsafe) { 1744 force_sig_specific(SIGKILL, current); 1745 return; 1746 } 1747 if (tsec->osid == tsec->sid) 1748 return; 1749 1750 /* Close files for which the new task SID is not authorized. */ 1751 flush_unauthorized_files(current->files); 1752 1753 /* Check whether the new SID can inherit signal state 1754 from the old SID. If not, clear itimers to avoid 1755 subsequent signal generation and flush and unblock 1756 signals. This must occur _after_ the task SID has 1757 been updated so that any kill done after the flush 1758 will be checked against the new SID. */ 1759 rc = avc_has_perm(tsec->osid, tsec->sid, SECCLASS_PROCESS, 1760 PROCESS__SIGINH, NULL); 1761 if (rc) { 1762 memset(&itimer, 0, sizeof itimer); 1763 for (i = 0; i < 3; i++) 1764 do_setitimer(i, &itimer, NULL); 1765 flush_signals(current); 1766 spin_lock_irq(¤t->sighand->siglock); 1767 flush_signal_handlers(current, 1); 1768 sigemptyset(¤t->blocked); 1769 recalc_sigpending(); 1770 spin_unlock_irq(¤t->sighand->siglock); 1771 } 1772 1773 /* Check whether the new SID can inherit resource limits 1774 from the old SID. If not, reset all soft limits to 1775 the lower of the current task's hard limit and the init 1776 task's soft limit. Note that the setting of hard limits 1777 (even to lower them) can be controlled by the setrlimit 1778 check. The inclusion of the init task's soft limit into 1779 the computation is to avoid resetting soft limits higher 1780 than the default soft limit for cases where the default 1781 is lower than the hard limit, e.g. RLIMIT_CORE or 1782 RLIMIT_STACK.*/ 1783 rc = avc_has_perm(tsec->osid, tsec->sid, SECCLASS_PROCESS, 1784 PROCESS__RLIMITINH, NULL); 1785 if (rc) { 1786 for (i = 0; i < RLIM_NLIMITS; i++) { 1787 rlim = current->signal->rlim + i; 1788 initrlim = init_task.signal->rlim+i; 1789 rlim->rlim_cur = min(rlim->rlim_max,initrlim->rlim_cur); 1790 } 1791 if (current->signal->rlim[RLIMIT_CPU].rlim_cur != RLIM_INFINITY) { 1792 /* 1793 * This will cause RLIMIT_CPU calculations 1794 * to be refigured. 1795 */ 1796 current->it_prof_expires = jiffies_to_cputime(1); 1797 } 1798 } 1799 1800 /* Wake up the parent if it is waiting so that it can 1801 recheck wait permission to the new task SID. */ 1802 wake_up_interruptible(¤t->parent->signal->wait_chldexit); 1803 } 1804 1805 /* superblock security operations */ 1806 1807 static int selinux_sb_alloc_security(struct super_block *sb) 1808 { 1809 return superblock_alloc_security(sb); 1810 } 1811 1812 static void selinux_sb_free_security(struct super_block *sb) 1813 { 1814 superblock_free_security(sb); 1815 } 1816 1817 static inline int match_prefix(char *prefix, int plen, char *option, int olen) 1818 { 1819 if (plen > olen) 1820 return 0; 1821 1822 return !memcmp(prefix, option, plen); 1823 } 1824 1825 static inline int selinux_option(char *option, int len) 1826 { 1827 return (match_prefix("context=", sizeof("context=")-1, option, len) || 1828 match_prefix("fscontext=", sizeof("fscontext=")-1, option, len) || 1829 match_prefix("defcontext=", sizeof("defcontext=")-1, option, len)); 1830 } 1831 1832 static inline void take_option(char **to, char *from, int *first, int len) 1833 { 1834 if (!*first) { 1835 **to = ','; 1836 *to += 1; 1837 } 1838 else 1839 *first = 0; 1840 memcpy(*to, from, len); 1841 *to += len; 1842 } 1843 1844 static int selinux_sb_copy_data(struct file_system_type *type, void *orig, void *copy) 1845 { 1846 int fnosec, fsec, rc = 0; 1847 char *in_save, *in_curr, *in_end; 1848 char *sec_curr, *nosec_save, *nosec; 1849 1850 in_curr = orig; 1851 sec_curr = copy; 1852 1853 /* Binary mount data: just copy */ 1854 if (type->fs_flags & FS_BINARY_MOUNTDATA) { 1855 copy_page(sec_curr, in_curr); 1856 goto out; 1857 } 1858 1859 nosec = (char *)get_zeroed_page(GFP_KERNEL); 1860 if (!nosec) { 1861 rc = -ENOMEM; 1862 goto out; 1863 } 1864 1865 nosec_save = nosec; 1866 fnosec = fsec = 1; 1867 in_save = in_end = orig; 1868 1869 do { 1870 if (*in_end == ',' || *in_end == '\0') { 1871 int len = in_end - in_curr; 1872 1873 if (selinux_option(in_curr, len)) 1874 take_option(&sec_curr, in_curr, &fsec, len); 1875 else 1876 take_option(&nosec, in_curr, &fnosec, len); 1877 1878 in_curr = in_end + 1; 1879 } 1880 } while (*in_end++); 1881 1882 strcpy(in_save, nosec_save); 1883 free_page((unsigned long)nosec_save); 1884 out: 1885 return rc; 1886 } 1887 1888 static int selinux_sb_kern_mount(struct super_block *sb, void *data) 1889 { 1890 struct avc_audit_data ad; 1891 int rc; 1892 1893 rc = superblock_doinit(sb, data); 1894 if (rc) 1895 return rc; 1896 1897 AVC_AUDIT_DATA_INIT(&ad,FS); 1898 ad.u.fs.dentry = sb->s_root; 1899 return superblock_has_perm(current, sb, FILESYSTEM__MOUNT, &ad); 1900 } 1901 1902 static int selinux_sb_statfs(struct super_block *sb) 1903 { 1904 struct avc_audit_data ad; 1905 1906 AVC_AUDIT_DATA_INIT(&ad,FS); 1907 ad.u.fs.dentry = sb->s_root; 1908 return superblock_has_perm(current, sb, FILESYSTEM__GETATTR, &ad); 1909 } 1910 1911 static int selinux_mount(char * dev_name, 1912 struct nameidata *nd, 1913 char * type, 1914 unsigned long flags, 1915 void * data) 1916 { 1917 int rc; 1918 1919 rc = secondary_ops->sb_mount(dev_name, nd, type, flags, data); 1920 if (rc) 1921 return rc; 1922 1923 if (flags & MS_REMOUNT) 1924 return superblock_has_perm(current, nd->mnt->mnt_sb, 1925 FILESYSTEM__REMOUNT, NULL); 1926 else 1927 return dentry_has_perm(current, nd->mnt, nd->dentry, 1928 FILE__MOUNTON); 1929 } 1930 1931 static int selinux_umount(struct vfsmount *mnt, int flags) 1932 { 1933 int rc; 1934 1935 rc = secondary_ops->sb_umount(mnt, flags); 1936 if (rc) 1937 return rc; 1938 1939 return superblock_has_perm(current,mnt->mnt_sb, 1940 FILESYSTEM__UNMOUNT,NULL); 1941 } 1942 1943 /* inode security operations */ 1944 1945 static int selinux_inode_alloc_security(struct inode *inode) 1946 { 1947 return inode_alloc_security(inode); 1948 } 1949 1950 static void selinux_inode_free_security(struct inode *inode) 1951 { 1952 inode_free_security(inode); 1953 } 1954 1955 static int selinux_inode_init_security(struct inode *inode, struct inode *dir, 1956 char **name, void **value, 1957 size_t *len) 1958 { 1959 struct task_security_struct *tsec; 1960 struct inode_security_struct *dsec; 1961 struct superblock_security_struct *sbsec; 1962 struct inode_security_struct *isec; 1963 u32 newsid, clen; 1964 int rc; 1965 char *namep = NULL, *context; 1966 1967 tsec = current->security; 1968 dsec = dir->i_security; 1969 sbsec = dir->i_sb->s_security; 1970 isec = inode->i_security; 1971 1972 if (tsec->create_sid && sbsec->behavior != SECURITY_FS_USE_MNTPOINT) { 1973 newsid = tsec->create_sid; 1974 } else { 1975 rc = security_transition_sid(tsec->sid, dsec->sid, 1976 inode_mode_to_security_class(inode->i_mode), 1977 &newsid); 1978 if (rc) { 1979 printk(KERN_WARNING "%s: " 1980 "security_transition_sid failed, rc=%d (dev=%s " 1981 "ino=%ld)\n", 1982 __FUNCTION__, 1983 -rc, inode->i_sb->s_id, inode->i_ino); 1984 return rc; 1985 } 1986 } 1987 1988 inode_security_set_sid(inode, newsid); 1989 1990 if (sbsec->behavior == SECURITY_FS_USE_MNTPOINT) 1991 return -EOPNOTSUPP; 1992 1993 if (name) { 1994 namep = kstrdup(XATTR_SELINUX_SUFFIX, GFP_KERNEL); 1995 if (!namep) 1996 return -ENOMEM; 1997 *name = namep; 1998 } 1999 2000 if (value && len) { 2001 rc = security_sid_to_context(newsid, &context, &clen); 2002 if (rc) { 2003 kfree(namep); 2004 return rc; 2005 } 2006 *value = context; 2007 *len = clen; 2008 } 2009 2010 return 0; 2011 } 2012 2013 static int selinux_inode_create(struct inode *dir, struct dentry *dentry, int mask) 2014 { 2015 return may_create(dir, dentry, SECCLASS_FILE); 2016 } 2017 2018 static int selinux_inode_link(struct dentry *old_dentry, struct inode *dir, struct dentry *new_dentry) 2019 { 2020 int rc; 2021 2022 rc = secondary_ops->inode_link(old_dentry,dir,new_dentry); 2023 if (rc) 2024 return rc; 2025 return may_link(dir, old_dentry, MAY_LINK); 2026 } 2027 2028 static int selinux_inode_unlink(struct inode *dir, struct dentry *dentry) 2029 { 2030 int rc; 2031 2032 rc = secondary_ops->inode_unlink(dir, dentry); 2033 if (rc) 2034 return rc; 2035 return may_link(dir, dentry, MAY_UNLINK); 2036 } 2037 2038 static int selinux_inode_symlink(struct inode *dir, struct dentry *dentry, const char *name) 2039 { 2040 return may_create(dir, dentry, SECCLASS_LNK_FILE); 2041 } 2042 2043 static int selinux_inode_mkdir(struct inode *dir, struct dentry *dentry, int mask) 2044 { 2045 return may_create(dir, dentry, SECCLASS_DIR); 2046 } 2047 2048 static int selinux_inode_rmdir(struct inode *dir, struct dentry *dentry) 2049 { 2050 return may_link(dir, dentry, MAY_RMDIR); 2051 } 2052 2053 static int selinux_inode_mknod(struct inode *dir, struct dentry *dentry, int mode, dev_t dev) 2054 { 2055 int rc; 2056 2057 rc = secondary_ops->inode_mknod(dir, dentry, mode, dev); 2058 if (rc) 2059 return rc; 2060 2061 return may_create(dir, dentry, inode_mode_to_security_class(mode)); 2062 } 2063 2064 static int selinux_inode_rename(struct inode *old_inode, struct dentry *old_dentry, 2065 struct inode *new_inode, struct dentry *new_dentry) 2066 { 2067 return may_rename(old_inode, old_dentry, new_inode, new_dentry); 2068 } 2069 2070 static int selinux_inode_readlink(struct dentry *dentry) 2071 { 2072 return dentry_has_perm(current, NULL, dentry, FILE__READ); 2073 } 2074 2075 static int selinux_inode_follow_link(struct dentry *dentry, struct nameidata *nameidata) 2076 { 2077 int rc; 2078 2079 rc = secondary_ops->inode_follow_link(dentry,nameidata); 2080 if (rc) 2081 return rc; 2082 return dentry_has_perm(current, NULL, dentry, FILE__READ); 2083 } 2084 2085 static int selinux_inode_permission(struct inode *inode, int mask, 2086 struct nameidata *nd) 2087 { 2088 int rc; 2089 2090 rc = secondary_ops->inode_permission(inode, mask, nd); 2091 if (rc) 2092 return rc; 2093 2094 if (!mask) { 2095 /* No permission to check. Existence test. */ 2096 return 0; 2097 } 2098 2099 return inode_has_perm(current, inode, 2100 file_mask_to_av(inode->i_mode, mask), NULL); 2101 } 2102 2103 static int selinux_inode_setattr(struct dentry *dentry, struct iattr *iattr) 2104 { 2105 int rc; 2106 2107 rc = secondary_ops->inode_setattr(dentry, iattr); 2108 if (rc) 2109 return rc; 2110 2111 if (iattr->ia_valid & ATTR_FORCE) 2112 return 0; 2113 2114 if (iattr->ia_valid & (ATTR_MODE | ATTR_UID | ATTR_GID | 2115 ATTR_ATIME_SET | ATTR_MTIME_SET)) 2116 return dentry_has_perm(current, NULL, dentry, FILE__SETATTR); 2117 2118 return dentry_has_perm(current, NULL, dentry, FILE__WRITE); 2119 } 2120 2121 static int selinux_inode_getattr(struct vfsmount *mnt, struct dentry *dentry) 2122 { 2123 return dentry_has_perm(current, mnt, dentry, FILE__GETATTR); 2124 } 2125 2126 static int selinux_inode_setxattr(struct dentry *dentry, char *name, void *value, size_t size, int flags) 2127 { 2128 struct task_security_struct *tsec = current->security; 2129 struct inode *inode = dentry->d_inode; 2130 struct inode_security_struct *isec = inode->i_security; 2131 struct superblock_security_struct *sbsec; 2132 struct avc_audit_data ad; 2133 u32 newsid; 2134 int rc = 0; 2135 2136 if (strcmp(name, XATTR_NAME_SELINUX)) { 2137 if (!strncmp(name, XATTR_SECURITY_PREFIX, 2138 sizeof XATTR_SECURITY_PREFIX - 1) && 2139 !capable(CAP_SYS_ADMIN)) { 2140 /* A different attribute in the security namespace. 2141 Restrict to administrator. */ 2142 return -EPERM; 2143 } 2144 2145 /* Not an attribute we recognize, so just check the 2146 ordinary setattr permission. */ 2147 return dentry_has_perm(current, NULL, dentry, FILE__SETATTR); 2148 } 2149 2150 sbsec = inode->i_sb->s_security; 2151 if (sbsec->behavior == SECURITY_FS_USE_MNTPOINT) 2152 return -EOPNOTSUPP; 2153 2154 if ((current->fsuid != inode->i_uid) && !capable(CAP_FOWNER)) 2155 return -EPERM; 2156 2157 AVC_AUDIT_DATA_INIT(&ad,FS); 2158 ad.u.fs.dentry = dentry; 2159 2160 rc = avc_has_perm(tsec->sid, isec->sid, isec->sclass, 2161 FILE__RELABELFROM, &ad); 2162 if (rc) 2163 return rc; 2164 2165 rc = security_context_to_sid(value, size, &newsid); 2166 if (rc) 2167 return rc; 2168 2169 rc = avc_has_perm(tsec->sid, newsid, isec->sclass, 2170 FILE__RELABELTO, &ad); 2171 if (rc) 2172 return rc; 2173 2174 rc = security_validate_transition(isec->sid, newsid, tsec->sid, 2175 isec->sclass); 2176 if (rc) 2177 return rc; 2178 2179 return avc_has_perm(newsid, 2180 sbsec->sid, 2181 SECCLASS_FILESYSTEM, 2182 FILESYSTEM__ASSOCIATE, 2183 &ad); 2184 } 2185 2186 static void selinux_inode_post_setxattr(struct dentry *dentry, char *name, 2187 void *value, size_t size, int flags) 2188 { 2189 struct inode *inode = dentry->d_inode; 2190 struct inode_security_struct *isec = inode->i_security; 2191 u32 newsid; 2192 int rc; 2193 2194 if (strcmp(name, XATTR_NAME_SELINUX)) { 2195 /* Not an attribute we recognize, so nothing to do. */ 2196 return; 2197 } 2198 2199 rc = security_context_to_sid(value, size, &newsid); 2200 if (rc) { 2201 printk(KERN_WARNING "%s: unable to obtain SID for context " 2202 "%s, rc=%d\n", __FUNCTION__, (char*)value, -rc); 2203 return; 2204 } 2205 2206 isec->sid = newsid; 2207 return; 2208 } 2209 2210 static int selinux_inode_getxattr (struct dentry *dentry, char *name) 2211 { 2212 return dentry_has_perm(current, NULL, dentry, FILE__GETATTR); 2213 } 2214 2215 static int selinux_inode_listxattr (struct dentry *dentry) 2216 { 2217 return dentry_has_perm(current, NULL, dentry, FILE__GETATTR); 2218 } 2219 2220 static int selinux_inode_removexattr (struct dentry *dentry, char *name) 2221 { 2222 if (strcmp(name, XATTR_NAME_SELINUX)) { 2223 if (!strncmp(name, XATTR_SECURITY_PREFIX, 2224 sizeof XATTR_SECURITY_PREFIX - 1) && 2225 !capable(CAP_SYS_ADMIN)) { 2226 /* A different attribute in the security namespace. 2227 Restrict to administrator. */ 2228 return -EPERM; 2229 } 2230 2231 /* Not an attribute we recognize, so just check the 2232 ordinary setattr permission. Might want a separate 2233 permission for removexattr. */ 2234 return dentry_has_perm(current, NULL, dentry, FILE__SETATTR); 2235 } 2236 2237 /* No one is allowed to remove a SELinux security label. 2238 You can change the label, but all data must be labeled. */ 2239 return -EACCES; 2240 } 2241 2242 /* 2243 * Copy the in-core inode security context value to the user. If the 2244 * getxattr() prior to this succeeded, check to see if we need to 2245 * canonicalize the value to be finally returned to the user. 2246 * 2247 * Permission check is handled by selinux_inode_getxattr hook. 2248 */ 2249 static int selinux_inode_getsecurity(struct inode *inode, const char *name, void *buffer, size_t size, int err) 2250 { 2251 struct inode_security_struct *isec = inode->i_security; 2252 char *context; 2253 unsigned len; 2254 int rc; 2255 2256 if (strcmp(name, XATTR_SELINUX_SUFFIX)) { 2257 rc = -EOPNOTSUPP; 2258 goto out; 2259 } 2260 2261 rc = security_sid_to_context(isec->sid, &context, &len); 2262 if (rc) 2263 goto out; 2264 2265 /* Probe for required buffer size */ 2266 if (!buffer || !size) { 2267 rc = len; 2268 goto out_free; 2269 } 2270 2271 if (size < len) { 2272 rc = -ERANGE; 2273 goto out_free; 2274 } 2275 2276 if (err > 0) { 2277 if ((len == err) && !(memcmp(context, buffer, len))) { 2278 /* Don't need to canonicalize value */ 2279 rc = err; 2280 goto out_free; 2281 } 2282 memset(buffer, 0, size); 2283 } 2284 memcpy(buffer, context, len); 2285 rc = len; 2286 out_free: 2287 kfree(context); 2288 out: 2289 return rc; 2290 } 2291 2292 static int selinux_inode_setsecurity(struct inode *inode, const char *name, 2293 const void *value, size_t size, int flags) 2294 { 2295 struct inode_security_struct *isec = inode->i_security; 2296 u32 newsid; 2297 int rc; 2298 2299 if (strcmp(name, XATTR_SELINUX_SUFFIX)) 2300 return -EOPNOTSUPP; 2301 2302 if (!value || !size) 2303 return -EACCES; 2304 2305 rc = security_context_to_sid((void*)value, size, &newsid); 2306 if (rc) 2307 return rc; 2308 2309 isec->sid = newsid; 2310 return 0; 2311 } 2312 2313 static int selinux_inode_listsecurity(struct inode *inode, char *buffer, size_t buffer_size) 2314 { 2315 const int len = sizeof(XATTR_NAME_SELINUX); 2316 if (buffer && len <= buffer_size) 2317 memcpy(buffer, XATTR_NAME_SELINUX, len); 2318 return len; 2319 } 2320 2321 /* file security operations */ 2322 2323 static int selinux_file_permission(struct file *file, int mask) 2324 { 2325 struct inode *inode = file->f_dentry->d_inode; 2326 2327 if (!mask) { 2328 /* No permission to check. Existence test. */ 2329 return 0; 2330 } 2331 2332 /* file_mask_to_av won't add FILE__WRITE if MAY_APPEND is set */ 2333 if ((file->f_flags & O_APPEND) && (mask & MAY_WRITE)) 2334 mask |= MAY_APPEND; 2335 2336 return file_has_perm(current, file, 2337 file_mask_to_av(inode->i_mode, mask)); 2338 } 2339 2340 static int selinux_file_alloc_security(struct file *file) 2341 { 2342 return file_alloc_security(file); 2343 } 2344 2345 static void selinux_file_free_security(struct file *file) 2346 { 2347 file_free_security(file); 2348 } 2349 2350 static int selinux_file_ioctl(struct file *file, unsigned int cmd, 2351 unsigned long arg) 2352 { 2353 int error = 0; 2354 2355 switch (cmd) { 2356 case FIONREAD: 2357 /* fall through */ 2358 case FIBMAP: 2359 /* fall through */ 2360 case FIGETBSZ: 2361 /* fall through */ 2362 case EXT2_IOC_GETFLAGS: 2363 /* fall through */ 2364 case EXT2_IOC_GETVERSION: 2365 error = file_has_perm(current, file, FILE__GETATTR); 2366 break; 2367 2368 case EXT2_IOC_SETFLAGS: 2369 /* fall through */ 2370 case EXT2_IOC_SETVERSION: 2371 error = file_has_perm(current, file, FILE__SETATTR); 2372 break; 2373 2374 /* sys_ioctl() checks */ 2375 case FIONBIO: 2376 /* fall through */ 2377 case FIOASYNC: 2378 error = file_has_perm(current, file, 0); 2379 break; 2380 2381 case KDSKBENT: 2382 case KDSKBSENT: 2383 error = task_has_capability(current,CAP_SYS_TTY_CONFIG); 2384 break; 2385 2386 /* default case assumes that the command will go 2387 * to the file's ioctl() function. 2388 */ 2389 default: 2390 error = file_has_perm(current, file, FILE__IOCTL); 2391 2392 } 2393 return error; 2394 } 2395 2396 static int file_map_prot_check(struct file *file, unsigned long prot, int shared) 2397 { 2398 #ifndef CONFIG_PPC32 2399 if ((prot & PROT_EXEC) && (!file || (!shared && (prot & PROT_WRITE)))) { 2400 /* 2401 * We are making executable an anonymous mapping or a 2402 * private file mapping that will also be writable. 2403 * This has an additional check. 2404 */ 2405 int rc = task_has_perm(current, current, PROCESS__EXECMEM); 2406 if (rc) 2407 return rc; 2408 } 2409 #endif 2410 2411 if (file) { 2412 /* read access is always possible with a mapping */ 2413 u32 av = FILE__READ; 2414 2415 /* write access only matters if the mapping is shared */ 2416 if (shared && (prot & PROT_WRITE)) 2417 av |= FILE__WRITE; 2418 2419 if (prot & PROT_EXEC) 2420 av |= FILE__EXECUTE; 2421 2422 return file_has_perm(current, file, av); 2423 } 2424 return 0; 2425 } 2426 2427 static int selinux_file_mmap(struct file *file, unsigned long reqprot, 2428 unsigned long prot, unsigned long flags) 2429 { 2430 int rc; 2431 2432 rc = secondary_ops->file_mmap(file, reqprot, prot, flags); 2433 if (rc) 2434 return rc; 2435 2436 if (selinux_checkreqprot) 2437 prot = reqprot; 2438 2439 return file_map_prot_check(file, prot, 2440 (flags & MAP_TYPE) == MAP_SHARED); 2441 } 2442 2443 static int selinux_file_mprotect(struct vm_area_struct *vma, 2444 unsigned long reqprot, 2445 unsigned long prot) 2446 { 2447 int rc; 2448 2449 rc = secondary_ops->file_mprotect(vma, reqprot, prot); 2450 if (rc) 2451 return rc; 2452 2453 if (selinux_checkreqprot) 2454 prot = reqprot; 2455 2456 #ifndef CONFIG_PPC32 2457 if ((prot & PROT_EXEC) && !(vma->vm_flags & VM_EXECUTABLE) && 2458 (vma->vm_start >= vma->vm_mm->start_brk && 2459 vma->vm_end <= vma->vm_mm->brk)) { 2460 /* 2461 * We are making an executable mapping in the brk region. 2462 * This has an additional execheap check. 2463 */ 2464 rc = task_has_perm(current, current, PROCESS__EXECHEAP); 2465 if (rc) 2466 return rc; 2467 } 2468 if (vma->vm_file != NULL && vma->anon_vma != NULL && (prot & PROT_EXEC)) { 2469 /* 2470 * We are making executable a file mapping that has 2471 * had some COW done. Since pages might have been written, 2472 * check ability to execute the possibly modified content. 2473 * This typically should only occur for text relocations. 2474 */ 2475 int rc = file_has_perm(current, vma->vm_file, FILE__EXECMOD); 2476 if (rc) 2477 return rc; 2478 } 2479 if (!vma->vm_file && (prot & PROT_EXEC) && 2480 vma->vm_start <= vma->vm_mm->start_stack && 2481 vma->vm_end >= vma->vm_mm->start_stack) { 2482 /* Attempt to make the process stack executable. 2483 * This has an additional execstack check. 2484 */ 2485 rc = task_has_perm(current, current, PROCESS__EXECSTACK); 2486 if (rc) 2487 return rc; 2488 } 2489 #endif 2490 2491 return file_map_prot_check(vma->vm_file, prot, vma->vm_flags&VM_SHARED); 2492 } 2493 2494 static int selinux_file_lock(struct file *file, unsigned int cmd) 2495 { 2496 return file_has_perm(current, file, FILE__LOCK); 2497 } 2498 2499 static int selinux_file_fcntl(struct file *file, unsigned int cmd, 2500 unsigned long arg) 2501 { 2502 int err = 0; 2503 2504 switch (cmd) { 2505 case F_SETFL: 2506 if (!file->f_dentry || !file->f_dentry->d_inode) { 2507 err = -EINVAL; 2508 break; 2509 } 2510 2511 if ((file->f_flags & O_APPEND) && !(arg & O_APPEND)) { 2512 err = file_has_perm(current, file,FILE__WRITE); 2513 break; 2514 } 2515 /* fall through */ 2516 case F_SETOWN: 2517 case F_SETSIG: 2518 case F_GETFL: 2519 case F_GETOWN: 2520 case F_GETSIG: 2521 /* Just check FD__USE permission */ 2522 err = file_has_perm(current, file, 0); 2523 break; 2524 case F_GETLK: 2525 case F_SETLK: 2526 case F_SETLKW: 2527 #if BITS_PER_LONG == 32 2528 case F_GETLK64: 2529 case F_SETLK64: 2530 case F_SETLKW64: 2531 #endif 2532 if (!file->f_dentry || !file->f_dentry->d_inode) { 2533 err = -EINVAL; 2534 break; 2535 } 2536 err = file_has_perm(current, file, FILE__LOCK); 2537 break; 2538 } 2539 2540 return err; 2541 } 2542 2543 static int selinux_file_set_fowner(struct file *file) 2544 { 2545 struct task_security_struct *tsec; 2546 struct file_security_struct *fsec; 2547 2548 tsec = current->security; 2549 fsec = file->f_security; 2550 fsec->fown_sid = tsec->sid; 2551 2552 return 0; 2553 } 2554 2555 static int selinux_file_send_sigiotask(struct task_struct *tsk, 2556 struct fown_struct *fown, int signum) 2557 { 2558 struct file *file; 2559 u32 perm; 2560 struct task_security_struct *tsec; 2561 struct file_security_struct *fsec; 2562 2563 /* struct fown_struct is never outside the context of a struct file */ 2564 file = (struct file *)((long)fown - offsetof(struct file,f_owner)); 2565 2566 tsec = tsk->security; 2567 fsec = file->f_security; 2568 2569 if (!signum) 2570 perm = signal_to_av(SIGIO); /* as per send_sigio_to_task */ 2571 else 2572 perm = signal_to_av(signum); 2573 2574 return avc_has_perm(fsec->fown_sid, tsec->sid, 2575 SECCLASS_PROCESS, perm, NULL); 2576 } 2577 2578 static int selinux_file_receive(struct file *file) 2579 { 2580 return file_has_perm(current, file, file_to_av(file)); 2581 } 2582 2583 /* task security operations */ 2584 2585 static int selinux_task_create(unsigned long clone_flags) 2586 { 2587 int rc; 2588 2589 rc = secondary_ops->task_create(clone_flags); 2590 if (rc) 2591 return rc; 2592 2593 return task_has_perm(current, current, PROCESS__FORK); 2594 } 2595 2596 static int selinux_task_alloc_security(struct task_struct *tsk) 2597 { 2598 struct task_security_struct *tsec1, *tsec2; 2599 int rc; 2600 2601 tsec1 = current->security; 2602 2603 rc = task_alloc_security(tsk); 2604 if (rc) 2605 return rc; 2606 tsec2 = tsk->security; 2607 2608 tsec2->osid = tsec1->osid; 2609 tsec2->sid = tsec1->sid; 2610 2611 /* Retain the exec and create SIDs across fork */ 2612 tsec2->exec_sid = tsec1->exec_sid; 2613 tsec2->create_sid = tsec1->create_sid; 2614 2615 /* Retain ptracer SID across fork, if any. 2616 This will be reset by the ptrace hook upon any 2617 subsequent ptrace_attach operations. */ 2618 tsec2->ptrace_sid = tsec1->ptrace_sid; 2619 2620 return 0; 2621 } 2622 2623 static void selinux_task_free_security(struct task_struct *tsk) 2624 { 2625 task_free_security(tsk); 2626 } 2627 2628 static int selinux_task_setuid(uid_t id0, uid_t id1, uid_t id2, int flags) 2629 { 2630 /* Since setuid only affects the current process, and 2631 since the SELinux controls are not based on the Linux 2632 identity attributes, SELinux does not need to control 2633 this operation. However, SELinux does control the use 2634 of the CAP_SETUID and CAP_SETGID capabilities using the 2635 capable hook. */ 2636 return 0; 2637 } 2638 2639 static int selinux_task_post_setuid(uid_t id0, uid_t id1, uid_t id2, int flags) 2640 { 2641 return secondary_ops->task_post_setuid(id0,id1,id2,flags); 2642 } 2643 2644 static int selinux_task_setgid(gid_t id0, gid_t id1, gid_t id2, int flags) 2645 { 2646 /* See the comment for setuid above. */ 2647 return 0; 2648 } 2649 2650 static int selinux_task_setpgid(struct task_struct *p, pid_t pgid) 2651 { 2652 return task_has_perm(current, p, PROCESS__SETPGID); 2653 } 2654 2655 static int selinux_task_getpgid(struct task_struct *p) 2656 { 2657 return task_has_perm(current, p, PROCESS__GETPGID); 2658 } 2659 2660 static int selinux_task_getsid(struct task_struct *p) 2661 { 2662 return task_has_perm(current, p, PROCESS__GETSESSION); 2663 } 2664 2665 static int selinux_task_setgroups(struct group_info *group_info) 2666 { 2667 /* See the comment for setuid above. */ 2668 return 0; 2669 } 2670 2671 static int selinux_task_setnice(struct task_struct *p, int nice) 2672 { 2673 int rc; 2674 2675 rc = secondary_ops->task_setnice(p, nice); 2676 if (rc) 2677 return rc; 2678 2679 return task_has_perm(current,p, PROCESS__SETSCHED); 2680 } 2681 2682 static int selinux_task_setrlimit(unsigned int resource, struct rlimit *new_rlim) 2683 { 2684 struct rlimit *old_rlim = current->signal->rlim + resource; 2685 int rc; 2686 2687 rc = secondary_ops->task_setrlimit(resource, new_rlim); 2688 if (rc) 2689 return rc; 2690 2691 /* Control the ability to change the hard limit (whether 2692 lowering or raising it), so that the hard limit can 2693 later be used as a safe reset point for the soft limit 2694 upon context transitions. See selinux_bprm_apply_creds. */ 2695 if (old_rlim->rlim_max != new_rlim->rlim_max) 2696 return task_has_perm(current, current, PROCESS__SETRLIMIT); 2697 2698 return 0; 2699 } 2700 2701 static int selinux_task_setscheduler(struct task_struct *p, int policy, struct sched_param *lp) 2702 { 2703 return task_has_perm(current, p, PROCESS__SETSCHED); 2704 } 2705 2706 static int selinux_task_getscheduler(struct task_struct *p) 2707 { 2708 return task_has_perm(current, p, PROCESS__GETSCHED); 2709 } 2710 2711 static int selinux_task_kill(struct task_struct *p, struct siginfo *info, int sig) 2712 { 2713 u32 perm; 2714 int rc; 2715 2716 rc = secondary_ops->task_kill(p, info, sig); 2717 if (rc) 2718 return rc; 2719 2720 if (info != SEND_SIG_NOINFO && (is_si_special(info) || SI_FROMKERNEL(info))) 2721 return 0; 2722 2723 if (!sig) 2724 perm = PROCESS__SIGNULL; /* null signal; existence test */ 2725 else 2726 perm = signal_to_av(sig); 2727 2728 return task_has_perm(current, p, perm); 2729 } 2730 2731 static int selinux_task_prctl(int option, 2732 unsigned long arg2, 2733 unsigned long arg3, 2734 unsigned long arg4, 2735 unsigned long arg5) 2736 { 2737 /* The current prctl operations do not appear to require 2738 any SELinux controls since they merely observe or modify 2739 the state of the current process. */ 2740 return 0; 2741 } 2742 2743 static int selinux_task_wait(struct task_struct *p) 2744 { 2745 u32 perm; 2746 2747 perm = signal_to_av(p->exit_signal); 2748 2749 return task_has_perm(p, current, perm); 2750 } 2751 2752 static void selinux_task_reparent_to_init(struct task_struct *p) 2753 { 2754 struct task_security_struct *tsec; 2755 2756 secondary_ops->task_reparent_to_init(p); 2757 2758 tsec = p->security; 2759 tsec->osid = tsec->sid; 2760 tsec->sid = SECINITSID_KERNEL; 2761 return; 2762 } 2763 2764 static void selinux_task_to_inode(struct task_struct *p, 2765 struct inode *inode) 2766 { 2767 struct task_security_struct *tsec = p->security; 2768 struct inode_security_struct *isec = inode->i_security; 2769 2770 isec->sid = tsec->sid; 2771 isec->initialized = 1; 2772 return; 2773 } 2774 2775 #ifdef CONFIG_SECURITY_NETWORK 2776 2777 /* Returns error only if unable to parse addresses */ 2778 static int selinux_parse_skb_ipv4(struct sk_buff *skb, struct avc_audit_data *ad) 2779 { 2780 int offset, ihlen, ret = -EINVAL; 2781 struct iphdr _iph, *ih; 2782 2783 offset = skb->nh.raw - skb->data; 2784 ih = skb_header_pointer(skb, offset, sizeof(_iph), &_iph); 2785 if (ih == NULL) 2786 goto out; 2787 2788 ihlen = ih->ihl * 4; 2789 if (ihlen < sizeof(_iph)) 2790 goto out; 2791 2792 ad->u.net.v4info.saddr = ih->saddr; 2793 ad->u.net.v4info.daddr = ih->daddr; 2794 ret = 0; 2795 2796 switch (ih->protocol) { 2797 case IPPROTO_TCP: { 2798 struct tcphdr _tcph, *th; 2799 2800 if (ntohs(ih->frag_off) & IP_OFFSET) 2801 break; 2802 2803 offset += ihlen; 2804 th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph); 2805 if (th == NULL) 2806 break; 2807 2808 ad->u.net.sport = th->source; 2809 ad->u.net.dport = th->dest; 2810 break; 2811 } 2812 2813 case IPPROTO_UDP: { 2814 struct udphdr _udph, *uh; 2815 2816 if (ntohs(ih->frag_off) & IP_OFFSET) 2817 break; 2818 2819 offset += ihlen; 2820 uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph); 2821 if (uh == NULL) 2822 break; 2823 2824 ad->u.net.sport = uh->source; 2825 ad->u.net.dport = uh->dest; 2826 break; 2827 } 2828 2829 default: 2830 break; 2831 } 2832 out: 2833 return ret; 2834 } 2835 2836 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE) 2837 2838 /* Returns error only if unable to parse addresses */ 2839 static int selinux_parse_skb_ipv6(struct sk_buff *skb, struct avc_audit_data *ad) 2840 { 2841 u8 nexthdr; 2842 int ret = -EINVAL, offset; 2843 struct ipv6hdr _ipv6h, *ip6; 2844 2845 offset = skb->nh.raw - skb->data; 2846 ip6 = skb_header_pointer(skb, offset, sizeof(_ipv6h), &_ipv6h); 2847 if (ip6 == NULL) 2848 goto out; 2849 2850 ipv6_addr_copy(&ad->u.net.v6info.saddr, &ip6->saddr); 2851 ipv6_addr_copy(&ad->u.net.v6info.daddr, &ip6->daddr); 2852 ret = 0; 2853 2854 nexthdr = ip6->nexthdr; 2855 offset += sizeof(_ipv6h); 2856 offset = ipv6_skip_exthdr(skb, offset, &nexthdr); 2857 if (offset < 0) 2858 goto out; 2859 2860 switch (nexthdr) { 2861 case IPPROTO_TCP: { 2862 struct tcphdr _tcph, *th; 2863 2864 th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph); 2865 if (th == NULL) 2866 break; 2867 2868 ad->u.net.sport = th->source; 2869 ad->u.net.dport = th->dest; 2870 break; 2871 } 2872 2873 case IPPROTO_UDP: { 2874 struct udphdr _udph, *uh; 2875 2876 uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph); 2877 if (uh == NULL) 2878 break; 2879 2880 ad->u.net.sport = uh->source; 2881 ad->u.net.dport = uh->dest; 2882 break; 2883 } 2884 2885 /* includes fragments */ 2886 default: 2887 break; 2888 } 2889 out: 2890 return ret; 2891 } 2892 2893 #endif /* IPV6 */ 2894 2895 static int selinux_parse_skb(struct sk_buff *skb, struct avc_audit_data *ad, 2896 char **addrp, int *len, int src) 2897 { 2898 int ret = 0; 2899 2900 switch (ad->u.net.family) { 2901 case PF_INET: 2902 ret = selinux_parse_skb_ipv4(skb, ad); 2903 if (ret || !addrp) 2904 break; 2905 *len = 4; 2906 *addrp = (char *)(src ? &ad->u.net.v4info.saddr : 2907 &ad->u.net.v4info.daddr); 2908 break; 2909 2910 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE) 2911 case PF_INET6: 2912 ret = selinux_parse_skb_ipv6(skb, ad); 2913 if (ret || !addrp) 2914 break; 2915 *len = 16; 2916 *addrp = (char *)(src ? &ad->u.net.v6info.saddr : 2917 &ad->u.net.v6info.daddr); 2918 break; 2919 #endif /* IPV6 */ 2920 default: 2921 break; 2922 } 2923 2924 return ret; 2925 } 2926 2927 /* socket security operations */ 2928 static int socket_has_perm(struct task_struct *task, struct socket *sock, 2929 u32 perms) 2930 { 2931 struct inode_security_struct *isec; 2932 struct task_security_struct *tsec; 2933 struct avc_audit_data ad; 2934 int err = 0; 2935 2936 tsec = task->security; 2937 isec = SOCK_INODE(sock)->i_security; 2938 2939 if (isec->sid == SECINITSID_KERNEL) 2940 goto out; 2941 2942 AVC_AUDIT_DATA_INIT(&ad,NET); 2943 ad.u.net.sk = sock->sk; 2944 err = avc_has_perm(tsec->sid, isec->sid, isec->sclass, perms, &ad); 2945 2946 out: 2947 return err; 2948 } 2949 2950 static int selinux_socket_create(int family, int type, 2951 int protocol, int kern) 2952 { 2953 int err = 0; 2954 struct task_security_struct *tsec; 2955 2956 if (kern) 2957 goto out; 2958 2959 tsec = current->security; 2960 err = avc_has_perm(tsec->sid, tsec->sid, 2961 socket_type_to_security_class(family, type, 2962 protocol), SOCKET__CREATE, NULL); 2963 2964 out: 2965 return err; 2966 } 2967 2968 static void selinux_socket_post_create(struct socket *sock, int family, 2969 int type, int protocol, int kern) 2970 { 2971 struct inode_security_struct *isec; 2972 struct task_security_struct *tsec; 2973 2974 isec = SOCK_INODE(sock)->i_security; 2975 2976 tsec = current->security; 2977 isec->sclass = socket_type_to_security_class(family, type, protocol); 2978 isec->sid = kern ? SECINITSID_KERNEL : tsec->sid; 2979 isec->initialized = 1; 2980 2981 return; 2982 } 2983 2984 /* Range of port numbers used to automatically bind. 2985 Need to determine whether we should perform a name_bind 2986 permission check between the socket and the port number. */ 2987 #define ip_local_port_range_0 sysctl_local_port_range[0] 2988 #define ip_local_port_range_1 sysctl_local_port_range[1] 2989 2990 static int selinux_socket_bind(struct socket *sock, struct sockaddr *address, int addrlen) 2991 { 2992 u16 family; 2993 int err; 2994 2995 err = socket_has_perm(current, sock, SOCKET__BIND); 2996 if (err) 2997 goto out; 2998 2999 /* 3000 * If PF_INET or PF_INET6, check name_bind permission for the port. 3001 * Multiple address binding for SCTP is not supported yet: we just 3002 * check the first address now. 3003 */ 3004 family = sock->sk->sk_family; 3005 if (family == PF_INET || family == PF_INET6) { 3006 char *addrp; 3007 struct inode_security_struct *isec; 3008 struct task_security_struct *tsec; 3009 struct avc_audit_data ad; 3010 struct sockaddr_in *addr4 = NULL; 3011 struct sockaddr_in6 *addr6 = NULL; 3012 unsigned short snum; 3013 struct sock *sk = sock->sk; 3014 u32 sid, node_perm, addrlen; 3015 3016 tsec = current->security; 3017 isec = SOCK_INODE(sock)->i_security; 3018 3019 if (family == PF_INET) { 3020 addr4 = (struct sockaddr_in *)address; 3021 snum = ntohs(addr4->sin_port); 3022 addrlen = sizeof(addr4->sin_addr.s_addr); 3023 addrp = (char *)&addr4->sin_addr.s_addr; 3024 } else { 3025 addr6 = (struct sockaddr_in6 *)address; 3026 snum = ntohs(addr6->sin6_port); 3027 addrlen = sizeof(addr6->sin6_addr.s6_addr); 3028 addrp = (char *)&addr6->sin6_addr.s6_addr; 3029 } 3030 3031 if (snum&&(snum < max(PROT_SOCK,ip_local_port_range_0) || 3032 snum > ip_local_port_range_1)) { 3033 err = security_port_sid(sk->sk_family, sk->sk_type, 3034 sk->sk_protocol, snum, &sid); 3035 if (err) 3036 goto out; 3037 AVC_AUDIT_DATA_INIT(&ad,NET); 3038 ad.u.net.sport = htons(snum); 3039 ad.u.net.family = family; 3040 err = avc_has_perm(isec->sid, sid, 3041 isec->sclass, 3042 SOCKET__NAME_BIND, &ad); 3043 if (err) 3044 goto out; 3045 } 3046 3047 switch(isec->sclass) { 3048 case SECCLASS_TCP_SOCKET: 3049 node_perm = TCP_SOCKET__NODE_BIND; 3050 break; 3051 3052 case SECCLASS_UDP_SOCKET: 3053 node_perm = UDP_SOCKET__NODE_BIND; 3054 break; 3055 3056 default: 3057 node_perm = RAWIP_SOCKET__NODE_BIND; 3058 break; 3059 } 3060 3061 err = security_node_sid(family, addrp, addrlen, &sid); 3062 if (err) 3063 goto out; 3064 3065 AVC_AUDIT_DATA_INIT(&ad,NET); 3066 ad.u.net.sport = htons(snum); 3067 ad.u.net.family = family; 3068 3069 if (family == PF_INET) 3070 ad.u.net.v4info.saddr = addr4->sin_addr.s_addr; 3071 else 3072 ipv6_addr_copy(&ad.u.net.v6info.saddr, &addr6->sin6_addr); 3073 3074 err = avc_has_perm(isec->sid, sid, 3075 isec->sclass, node_perm, &ad); 3076 if (err) 3077 goto out; 3078 } 3079 out: 3080 return err; 3081 } 3082 3083 static int selinux_socket_connect(struct socket *sock, struct sockaddr *address, int addrlen) 3084 { 3085 struct inode_security_struct *isec; 3086 int err; 3087 3088 err = socket_has_perm(current, sock, SOCKET__CONNECT); 3089 if (err) 3090 return err; 3091 3092 /* 3093 * If a TCP socket, check name_connect permission for the port. 3094 */ 3095 isec = SOCK_INODE(sock)->i_security; 3096 if (isec->sclass == SECCLASS_TCP_SOCKET) { 3097 struct sock *sk = sock->sk; 3098 struct avc_audit_data ad; 3099 struct sockaddr_in *addr4 = NULL; 3100 struct sockaddr_in6 *addr6 = NULL; 3101 unsigned short snum; 3102 u32 sid; 3103 3104 if (sk->sk_family == PF_INET) { 3105 addr4 = (struct sockaddr_in *)address; 3106 if (addrlen < sizeof(struct sockaddr_in)) 3107 return -EINVAL; 3108 snum = ntohs(addr4->sin_port); 3109 } else { 3110 addr6 = (struct sockaddr_in6 *)address; 3111 if (addrlen < SIN6_LEN_RFC2133) 3112 return -EINVAL; 3113 snum = ntohs(addr6->sin6_port); 3114 } 3115 3116 err = security_port_sid(sk->sk_family, sk->sk_type, 3117 sk->sk_protocol, snum, &sid); 3118 if (err) 3119 goto out; 3120 3121 AVC_AUDIT_DATA_INIT(&ad,NET); 3122 ad.u.net.dport = htons(snum); 3123 ad.u.net.family = sk->sk_family; 3124 err = avc_has_perm(isec->sid, sid, isec->sclass, 3125 TCP_SOCKET__NAME_CONNECT, &ad); 3126 if (err) 3127 goto out; 3128 } 3129 3130 out: 3131 return err; 3132 } 3133 3134 static int selinux_socket_listen(struct socket *sock, int backlog) 3135 { 3136 return socket_has_perm(current, sock, SOCKET__LISTEN); 3137 } 3138 3139 static int selinux_socket_accept(struct socket *sock, struct socket *newsock) 3140 { 3141 int err; 3142 struct inode_security_struct *isec; 3143 struct inode_security_struct *newisec; 3144 3145 err = socket_has_perm(current, sock, SOCKET__ACCEPT); 3146 if (err) 3147 return err; 3148 3149 newisec = SOCK_INODE(newsock)->i_security; 3150 3151 isec = SOCK_INODE(sock)->i_security; 3152 newisec->sclass = isec->sclass; 3153 newisec->sid = isec->sid; 3154 newisec->initialized = 1; 3155 3156 return 0; 3157 } 3158 3159 static int selinux_socket_sendmsg(struct socket *sock, struct msghdr *msg, 3160 int size) 3161 { 3162 return socket_has_perm(current, sock, SOCKET__WRITE); 3163 } 3164 3165 static int selinux_socket_recvmsg(struct socket *sock, struct msghdr *msg, 3166 int size, int flags) 3167 { 3168 return socket_has_perm(current, sock, SOCKET__READ); 3169 } 3170 3171 static int selinux_socket_getsockname(struct socket *sock) 3172 { 3173 return socket_has_perm(current, sock, SOCKET__GETATTR); 3174 } 3175 3176 static int selinux_socket_getpeername(struct socket *sock) 3177 { 3178 return socket_has_perm(current, sock, SOCKET__GETATTR); 3179 } 3180 3181 static int selinux_socket_setsockopt(struct socket *sock,int level,int optname) 3182 { 3183 return socket_has_perm(current, sock, SOCKET__SETOPT); 3184 } 3185 3186 static int selinux_socket_getsockopt(struct socket *sock, int level, 3187 int optname) 3188 { 3189 return socket_has_perm(current, sock, SOCKET__GETOPT); 3190 } 3191 3192 static int selinux_socket_shutdown(struct socket *sock, int how) 3193 { 3194 return socket_has_perm(current, sock, SOCKET__SHUTDOWN); 3195 } 3196 3197 static int selinux_socket_unix_stream_connect(struct socket *sock, 3198 struct socket *other, 3199 struct sock *newsk) 3200 { 3201 struct sk_security_struct *ssec; 3202 struct inode_security_struct *isec; 3203 struct inode_security_struct *other_isec; 3204 struct avc_audit_data ad; 3205 int err; 3206 3207 err = secondary_ops->unix_stream_connect(sock, other, newsk); 3208 if (err) 3209 return err; 3210 3211 isec = SOCK_INODE(sock)->i_security; 3212 other_isec = SOCK_INODE(other)->i_security; 3213 3214 AVC_AUDIT_DATA_INIT(&ad,NET); 3215 ad.u.net.sk = other->sk; 3216 3217 err = avc_has_perm(isec->sid, other_isec->sid, 3218 isec->sclass, 3219 UNIX_STREAM_SOCKET__CONNECTTO, &ad); 3220 if (err) 3221 return err; 3222 3223 /* connecting socket */ 3224 ssec = sock->sk->sk_security; 3225 ssec->peer_sid = other_isec->sid; 3226 3227 /* server child socket */ 3228 ssec = newsk->sk_security; 3229 ssec->peer_sid = isec->sid; 3230 3231 return 0; 3232 } 3233 3234 static int selinux_socket_unix_may_send(struct socket *sock, 3235 struct socket *other) 3236 { 3237 struct inode_security_struct *isec; 3238 struct inode_security_struct *other_isec; 3239 struct avc_audit_data ad; 3240 int err; 3241 3242 isec = SOCK_INODE(sock)->i_security; 3243 other_isec = SOCK_INODE(other)->i_security; 3244 3245 AVC_AUDIT_DATA_INIT(&ad,NET); 3246 ad.u.net.sk = other->sk; 3247 3248 err = avc_has_perm(isec->sid, other_isec->sid, 3249 isec->sclass, SOCKET__SENDTO, &ad); 3250 if (err) 3251 return err; 3252 3253 return 0; 3254 } 3255 3256 static int selinux_socket_sock_rcv_skb(struct sock *sk, struct sk_buff *skb) 3257 { 3258 u16 family; 3259 char *addrp; 3260 int len, err = 0; 3261 u32 netif_perm, node_perm, node_sid, if_sid, recv_perm = 0; 3262 u32 sock_sid = 0; 3263 u16 sock_class = 0; 3264 struct socket *sock; 3265 struct net_device *dev; 3266 struct avc_audit_data ad; 3267 3268 family = sk->sk_family; 3269 if (family != PF_INET && family != PF_INET6) 3270 goto out; 3271 3272 /* Handle mapped IPv4 packets arriving via IPv6 sockets */ 3273 if (family == PF_INET6 && skb->protocol == ntohs(ETH_P_IP)) 3274 family = PF_INET; 3275 3276 read_lock_bh(&sk->sk_callback_lock); 3277 sock = sk->sk_socket; 3278 if (sock) { 3279 struct inode *inode; 3280 inode = SOCK_INODE(sock); 3281 if (inode) { 3282 struct inode_security_struct *isec; 3283 isec = inode->i_security; 3284 sock_sid = isec->sid; 3285 sock_class = isec->sclass; 3286 } 3287 } 3288 read_unlock_bh(&sk->sk_callback_lock); 3289 if (!sock_sid) 3290 goto out; 3291 3292 dev = skb->dev; 3293 if (!dev) 3294 goto out; 3295 3296 err = sel_netif_sids(dev, &if_sid, NULL); 3297 if (err) 3298 goto out; 3299 3300 switch (sock_class) { 3301 case SECCLASS_UDP_SOCKET: 3302 netif_perm = NETIF__UDP_RECV; 3303 node_perm = NODE__UDP_RECV; 3304 recv_perm = UDP_SOCKET__RECV_MSG; 3305 break; 3306 3307 case SECCLASS_TCP_SOCKET: 3308 netif_perm = NETIF__TCP_RECV; 3309 node_perm = NODE__TCP_RECV; 3310 recv_perm = TCP_SOCKET__RECV_MSG; 3311 break; 3312 3313 default: 3314 netif_perm = NETIF__RAWIP_RECV; 3315 node_perm = NODE__RAWIP_RECV; 3316 break; 3317 } 3318 3319 AVC_AUDIT_DATA_INIT(&ad, NET); 3320 ad.u.net.netif = dev->name; 3321 ad.u.net.family = family; 3322 3323 err = selinux_parse_skb(skb, &ad, &addrp, &len, 1); 3324 if (err) 3325 goto out; 3326 3327 err = avc_has_perm(sock_sid, if_sid, SECCLASS_NETIF, netif_perm, &ad); 3328 if (err) 3329 goto out; 3330 3331 /* Fixme: this lookup is inefficient */ 3332 err = security_node_sid(family, addrp, len, &node_sid); 3333 if (err) 3334 goto out; 3335 3336 err = avc_has_perm(sock_sid, node_sid, SECCLASS_NODE, node_perm, &ad); 3337 if (err) 3338 goto out; 3339 3340 if (recv_perm) { 3341 u32 port_sid; 3342 3343 /* Fixme: make this more efficient */ 3344 err = security_port_sid(sk->sk_family, sk->sk_type, 3345 sk->sk_protocol, ntohs(ad.u.net.sport), 3346 &port_sid); 3347 if (err) 3348 goto out; 3349 3350 err = avc_has_perm(sock_sid, port_sid, 3351 sock_class, recv_perm, &ad); 3352 } 3353 3354 if (!err) 3355 err = selinux_xfrm_sock_rcv_skb(sock_sid, skb); 3356 3357 out: 3358 return err; 3359 } 3360 3361 static int selinux_socket_getpeersec(struct socket *sock, char __user *optval, 3362 int __user *optlen, unsigned len) 3363 { 3364 int err = 0; 3365 char *scontext; 3366 u32 scontext_len; 3367 struct sk_security_struct *ssec; 3368 struct inode_security_struct *isec; 3369 3370 isec = SOCK_INODE(sock)->i_security; 3371 if (isec->sclass != SECCLASS_UNIX_STREAM_SOCKET) { 3372 err = -ENOPROTOOPT; 3373 goto out; 3374 } 3375 3376 ssec = sock->sk->sk_security; 3377 3378 err = security_sid_to_context(ssec->peer_sid, &scontext, &scontext_len); 3379 if (err) 3380 goto out; 3381 3382 if (scontext_len > len) { 3383 err = -ERANGE; 3384 goto out_len; 3385 } 3386 3387 if (copy_to_user(optval, scontext, scontext_len)) 3388 err = -EFAULT; 3389 3390 out_len: 3391 if (put_user(scontext_len, optlen)) 3392 err = -EFAULT; 3393 3394 kfree(scontext); 3395 out: 3396 return err; 3397 } 3398 3399 static int selinux_sk_alloc_security(struct sock *sk, int family, gfp_t priority) 3400 { 3401 return sk_alloc_security(sk, family, priority); 3402 } 3403 3404 static void selinux_sk_free_security(struct sock *sk) 3405 { 3406 sk_free_security(sk); 3407 } 3408 3409 static unsigned int selinux_sk_getsid_security(struct sock *sk, struct flowi *fl, u8 dir) 3410 { 3411 struct inode_security_struct *isec; 3412 u32 sock_sid = SECINITSID_ANY_SOCKET; 3413 3414 if (!sk) 3415 return selinux_no_sk_sid(fl); 3416 3417 read_lock_bh(&sk->sk_callback_lock); 3418 isec = get_sock_isec(sk); 3419 3420 if (isec) 3421 sock_sid = isec->sid; 3422 3423 read_unlock_bh(&sk->sk_callback_lock); 3424 return sock_sid; 3425 } 3426 3427 static int selinux_nlmsg_perm(struct sock *sk, struct sk_buff *skb) 3428 { 3429 int err = 0; 3430 u32 perm; 3431 struct nlmsghdr *nlh; 3432 struct socket *sock = sk->sk_socket; 3433 struct inode_security_struct *isec = SOCK_INODE(sock)->i_security; 3434 3435 if (skb->len < NLMSG_SPACE(0)) { 3436 err = -EINVAL; 3437 goto out; 3438 } 3439 nlh = (struct nlmsghdr *)skb->data; 3440 3441 err = selinux_nlmsg_lookup(isec->sclass, nlh->nlmsg_type, &perm); 3442 if (err) { 3443 if (err == -EINVAL) { 3444 audit_log(current->audit_context, GFP_KERNEL, AUDIT_SELINUX_ERR, 3445 "SELinux: unrecognized netlink message" 3446 " type=%hu for sclass=%hu\n", 3447 nlh->nlmsg_type, isec->sclass); 3448 if (!selinux_enforcing) 3449 err = 0; 3450 } 3451 3452 /* Ignore */ 3453 if (err == -ENOENT) 3454 err = 0; 3455 goto out; 3456 } 3457 3458 err = socket_has_perm(current, sock, perm); 3459 out: 3460 return err; 3461 } 3462 3463 #ifdef CONFIG_NETFILTER 3464 3465 static unsigned int selinux_ip_postroute_last(unsigned int hooknum, 3466 struct sk_buff **pskb, 3467 const struct net_device *in, 3468 const struct net_device *out, 3469 int (*okfn)(struct sk_buff *), 3470 u16 family) 3471 { 3472 char *addrp; 3473 int len, err = NF_ACCEPT; 3474 u32 netif_perm, node_perm, node_sid, if_sid, send_perm = 0; 3475 struct sock *sk; 3476 struct socket *sock; 3477 struct inode *inode; 3478 struct sk_buff *skb = *pskb; 3479 struct inode_security_struct *isec; 3480 struct avc_audit_data ad; 3481 struct net_device *dev = (struct net_device *)out; 3482 3483 sk = skb->sk; 3484 if (!sk) 3485 goto out; 3486 3487 sock = sk->sk_socket; 3488 if (!sock) 3489 goto out; 3490 3491 inode = SOCK_INODE(sock); 3492 if (!inode) 3493 goto out; 3494 3495 err = sel_netif_sids(dev, &if_sid, NULL); 3496 if (err) 3497 goto out; 3498 3499 isec = inode->i_security; 3500 3501 switch (isec->sclass) { 3502 case SECCLASS_UDP_SOCKET: 3503 netif_perm = NETIF__UDP_SEND; 3504 node_perm = NODE__UDP_SEND; 3505 send_perm = UDP_SOCKET__SEND_MSG; 3506 break; 3507 3508 case SECCLASS_TCP_SOCKET: 3509 netif_perm = NETIF__TCP_SEND; 3510 node_perm = NODE__TCP_SEND; 3511 send_perm = TCP_SOCKET__SEND_MSG; 3512 break; 3513 3514 default: 3515 netif_perm = NETIF__RAWIP_SEND; 3516 node_perm = NODE__RAWIP_SEND; 3517 break; 3518 } 3519 3520 3521 AVC_AUDIT_DATA_INIT(&ad, NET); 3522 ad.u.net.netif = dev->name; 3523 ad.u.net.family = family; 3524 3525 err = selinux_parse_skb(skb, &ad, &addrp, 3526 &len, 0) ? NF_DROP : NF_ACCEPT; 3527 if (err != NF_ACCEPT) 3528 goto out; 3529 3530 err = avc_has_perm(isec->sid, if_sid, SECCLASS_NETIF, 3531 netif_perm, &ad) ? NF_DROP : NF_ACCEPT; 3532 if (err != NF_ACCEPT) 3533 goto out; 3534 3535 /* Fixme: this lookup is inefficient */ 3536 err = security_node_sid(family, addrp, len, 3537 &node_sid) ? NF_DROP : NF_ACCEPT; 3538 if (err != NF_ACCEPT) 3539 goto out; 3540 3541 err = avc_has_perm(isec->sid, node_sid, SECCLASS_NODE, 3542 node_perm, &ad) ? NF_DROP : NF_ACCEPT; 3543 if (err != NF_ACCEPT) 3544 goto out; 3545 3546 if (send_perm) { 3547 u32 port_sid; 3548 3549 /* Fixme: make this more efficient */ 3550 err = security_port_sid(sk->sk_family, 3551 sk->sk_type, 3552 sk->sk_protocol, 3553 ntohs(ad.u.net.dport), 3554 &port_sid) ? NF_DROP : NF_ACCEPT; 3555 if (err != NF_ACCEPT) 3556 goto out; 3557 3558 err = avc_has_perm(isec->sid, port_sid, isec->sclass, 3559 send_perm, &ad) ? NF_DROP : NF_ACCEPT; 3560 } 3561 3562 if (err != NF_ACCEPT) 3563 goto out; 3564 3565 err = selinux_xfrm_postroute_last(isec->sid, skb); 3566 3567 out: 3568 return err; 3569 } 3570 3571 static unsigned int selinux_ipv4_postroute_last(unsigned int hooknum, 3572 struct sk_buff **pskb, 3573 const struct net_device *in, 3574 const struct net_device *out, 3575 int (*okfn)(struct sk_buff *)) 3576 { 3577 return selinux_ip_postroute_last(hooknum, pskb, in, out, okfn, PF_INET); 3578 } 3579 3580 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE) 3581 3582 static unsigned int selinux_ipv6_postroute_last(unsigned int hooknum, 3583 struct sk_buff **pskb, 3584 const struct net_device *in, 3585 const struct net_device *out, 3586 int (*okfn)(struct sk_buff *)) 3587 { 3588 return selinux_ip_postroute_last(hooknum, pskb, in, out, okfn, PF_INET6); 3589 } 3590 3591 #endif /* IPV6 */ 3592 3593 #endif /* CONFIG_NETFILTER */ 3594 3595 #else 3596 3597 static inline int selinux_nlmsg_perm(struct sock *sk, struct sk_buff *skb) 3598 { 3599 return 0; 3600 } 3601 3602 #endif /* CONFIG_SECURITY_NETWORK */ 3603 3604 static int selinux_netlink_send(struct sock *sk, struct sk_buff *skb) 3605 { 3606 struct task_security_struct *tsec; 3607 struct av_decision avd; 3608 int err; 3609 3610 err = secondary_ops->netlink_send(sk, skb); 3611 if (err) 3612 return err; 3613 3614 tsec = current->security; 3615 3616 avd.allowed = 0; 3617 avc_has_perm_noaudit(tsec->sid, tsec->sid, 3618 SECCLASS_CAPABILITY, ~0, &avd); 3619 cap_mask(NETLINK_CB(skb).eff_cap, avd.allowed); 3620 3621 if (policydb_loaded_version >= POLICYDB_VERSION_NLCLASS) 3622 err = selinux_nlmsg_perm(sk, skb); 3623 3624 return err; 3625 } 3626 3627 static int selinux_netlink_recv(struct sk_buff *skb) 3628 { 3629 if (!cap_raised(NETLINK_CB(skb).eff_cap, CAP_NET_ADMIN)) 3630 return -EPERM; 3631 return 0; 3632 } 3633 3634 static int ipc_alloc_security(struct task_struct *task, 3635 struct kern_ipc_perm *perm, 3636 u16 sclass) 3637 { 3638 struct task_security_struct *tsec = task->security; 3639 struct ipc_security_struct *isec; 3640 3641 isec = kzalloc(sizeof(struct ipc_security_struct), GFP_KERNEL); 3642 if (!isec) 3643 return -ENOMEM; 3644 3645 isec->magic = SELINUX_MAGIC; 3646 isec->sclass = sclass; 3647 isec->ipc_perm = perm; 3648 if (tsec) { 3649 isec->sid = tsec->sid; 3650 } else { 3651 isec->sid = SECINITSID_UNLABELED; 3652 } 3653 perm->security = isec; 3654 3655 return 0; 3656 } 3657 3658 static void ipc_free_security(struct kern_ipc_perm *perm) 3659 { 3660 struct ipc_security_struct *isec = perm->security; 3661 if (!isec || isec->magic != SELINUX_MAGIC) 3662 return; 3663 3664 perm->security = NULL; 3665 kfree(isec); 3666 } 3667 3668 static int msg_msg_alloc_security(struct msg_msg *msg) 3669 { 3670 struct msg_security_struct *msec; 3671 3672 msec = kzalloc(sizeof(struct msg_security_struct), GFP_KERNEL); 3673 if (!msec) 3674 return -ENOMEM; 3675 3676 msec->magic = SELINUX_MAGIC; 3677 msec->msg = msg; 3678 msec->sid = SECINITSID_UNLABELED; 3679 msg->security = msec; 3680 3681 return 0; 3682 } 3683 3684 static void msg_msg_free_security(struct msg_msg *msg) 3685 { 3686 struct msg_security_struct *msec = msg->security; 3687 if (!msec || msec->magic != SELINUX_MAGIC) 3688 return; 3689 3690 msg->security = NULL; 3691 kfree(msec); 3692 } 3693 3694 static int ipc_has_perm(struct kern_ipc_perm *ipc_perms, 3695 u32 perms) 3696 { 3697 struct task_security_struct *tsec; 3698 struct ipc_security_struct *isec; 3699 struct avc_audit_data ad; 3700 3701 tsec = current->security; 3702 isec = ipc_perms->security; 3703 3704 AVC_AUDIT_DATA_INIT(&ad, IPC); 3705 ad.u.ipc_id = ipc_perms->key; 3706 3707 return avc_has_perm(tsec->sid, isec->sid, isec->sclass, perms, &ad); 3708 } 3709 3710 static int selinux_msg_msg_alloc_security(struct msg_msg *msg) 3711 { 3712 return msg_msg_alloc_security(msg); 3713 } 3714 3715 static void selinux_msg_msg_free_security(struct msg_msg *msg) 3716 { 3717 msg_msg_free_security(msg); 3718 } 3719 3720 /* message queue security operations */ 3721 static int selinux_msg_queue_alloc_security(struct msg_queue *msq) 3722 { 3723 struct task_security_struct *tsec; 3724 struct ipc_security_struct *isec; 3725 struct avc_audit_data ad; 3726 int rc; 3727 3728 rc = ipc_alloc_security(current, &msq->q_perm, SECCLASS_MSGQ); 3729 if (rc) 3730 return rc; 3731 3732 tsec = current->security; 3733 isec = msq->q_perm.security; 3734 3735 AVC_AUDIT_DATA_INIT(&ad, IPC); 3736 ad.u.ipc_id = msq->q_perm.key; 3737 3738 rc = avc_has_perm(tsec->sid, isec->sid, SECCLASS_MSGQ, 3739 MSGQ__CREATE, &ad); 3740 if (rc) { 3741 ipc_free_security(&msq->q_perm); 3742 return rc; 3743 } 3744 return 0; 3745 } 3746 3747 static void selinux_msg_queue_free_security(struct msg_queue *msq) 3748 { 3749 ipc_free_security(&msq->q_perm); 3750 } 3751 3752 static int selinux_msg_queue_associate(struct msg_queue *msq, int msqflg) 3753 { 3754 struct task_security_struct *tsec; 3755 struct ipc_security_struct *isec; 3756 struct avc_audit_data ad; 3757 3758 tsec = current->security; 3759 isec = msq->q_perm.security; 3760 3761 AVC_AUDIT_DATA_INIT(&ad, IPC); 3762 ad.u.ipc_id = msq->q_perm.key; 3763 3764 return avc_has_perm(tsec->sid, isec->sid, SECCLASS_MSGQ, 3765 MSGQ__ASSOCIATE, &ad); 3766 } 3767 3768 static int selinux_msg_queue_msgctl(struct msg_queue *msq, int cmd) 3769 { 3770 int err; 3771 int perms; 3772 3773 switch(cmd) { 3774 case IPC_INFO: 3775 case MSG_INFO: 3776 /* No specific object, just general system-wide information. */ 3777 return task_has_system(current, SYSTEM__IPC_INFO); 3778 case IPC_STAT: 3779 case MSG_STAT: 3780 perms = MSGQ__GETATTR | MSGQ__ASSOCIATE; 3781 break; 3782 case IPC_SET: 3783 perms = MSGQ__SETATTR; 3784 break; 3785 case IPC_RMID: 3786 perms = MSGQ__DESTROY; 3787 break; 3788 default: 3789 return 0; 3790 } 3791 3792 err = ipc_has_perm(&msq->q_perm, perms); 3793 return err; 3794 } 3795 3796 static int selinux_msg_queue_msgsnd(struct msg_queue *msq, struct msg_msg *msg, int msqflg) 3797 { 3798 struct task_security_struct *tsec; 3799 struct ipc_security_struct *isec; 3800 struct msg_security_struct *msec; 3801 struct avc_audit_data ad; 3802 int rc; 3803 3804 tsec = current->security; 3805 isec = msq->q_perm.security; 3806 msec = msg->security; 3807 3808 /* 3809 * First time through, need to assign label to the message 3810 */ 3811 if (msec->sid == SECINITSID_UNLABELED) { 3812 /* 3813 * Compute new sid based on current process and 3814 * message queue this message will be stored in 3815 */ 3816 rc = security_transition_sid(tsec->sid, 3817 isec->sid, 3818 SECCLASS_MSG, 3819 &msec->sid); 3820 if (rc) 3821 return rc; 3822 } 3823 3824 AVC_AUDIT_DATA_INIT(&ad, IPC); 3825 ad.u.ipc_id = msq->q_perm.key; 3826 3827 /* Can this process write to the queue? */ 3828 rc = avc_has_perm(tsec->sid, isec->sid, SECCLASS_MSGQ, 3829 MSGQ__WRITE, &ad); 3830 if (!rc) 3831 /* Can this process send the message */ 3832 rc = avc_has_perm(tsec->sid, msec->sid, 3833 SECCLASS_MSG, MSG__SEND, &ad); 3834 if (!rc) 3835 /* Can the message be put in the queue? */ 3836 rc = avc_has_perm(msec->sid, isec->sid, 3837 SECCLASS_MSGQ, MSGQ__ENQUEUE, &ad); 3838 3839 return rc; 3840 } 3841 3842 static int selinux_msg_queue_msgrcv(struct msg_queue *msq, struct msg_msg *msg, 3843 struct task_struct *target, 3844 long type, int mode) 3845 { 3846 struct task_security_struct *tsec; 3847 struct ipc_security_struct *isec; 3848 struct msg_security_struct *msec; 3849 struct avc_audit_data ad; 3850 int rc; 3851 3852 tsec = target->security; 3853 isec = msq->q_perm.security; 3854 msec = msg->security; 3855 3856 AVC_AUDIT_DATA_INIT(&ad, IPC); 3857 ad.u.ipc_id = msq->q_perm.key; 3858 3859 rc = avc_has_perm(tsec->sid, isec->sid, 3860 SECCLASS_MSGQ, MSGQ__READ, &ad); 3861 if (!rc) 3862 rc = avc_has_perm(tsec->sid, msec->sid, 3863 SECCLASS_MSG, MSG__RECEIVE, &ad); 3864 return rc; 3865 } 3866 3867 /* Shared Memory security operations */ 3868 static int selinux_shm_alloc_security(struct shmid_kernel *shp) 3869 { 3870 struct task_security_struct *tsec; 3871 struct ipc_security_struct *isec; 3872 struct avc_audit_data ad; 3873 int rc; 3874 3875 rc = ipc_alloc_security(current, &shp->shm_perm, SECCLASS_SHM); 3876 if (rc) 3877 return rc; 3878 3879 tsec = current->security; 3880 isec = shp->shm_perm.security; 3881 3882 AVC_AUDIT_DATA_INIT(&ad, IPC); 3883 ad.u.ipc_id = shp->shm_perm.key; 3884 3885 rc = avc_has_perm(tsec->sid, isec->sid, SECCLASS_SHM, 3886 SHM__CREATE, &ad); 3887 if (rc) { 3888 ipc_free_security(&shp->shm_perm); 3889 return rc; 3890 } 3891 return 0; 3892 } 3893 3894 static void selinux_shm_free_security(struct shmid_kernel *shp) 3895 { 3896 ipc_free_security(&shp->shm_perm); 3897 } 3898 3899 static int selinux_shm_associate(struct shmid_kernel *shp, int shmflg) 3900 { 3901 struct task_security_struct *tsec; 3902 struct ipc_security_struct *isec; 3903 struct avc_audit_data ad; 3904 3905 tsec = current->security; 3906 isec = shp->shm_perm.security; 3907 3908 AVC_AUDIT_DATA_INIT(&ad, IPC); 3909 ad.u.ipc_id = shp->shm_perm.key; 3910 3911 return avc_has_perm(tsec->sid, isec->sid, SECCLASS_SHM, 3912 SHM__ASSOCIATE, &ad); 3913 } 3914 3915 /* Note, at this point, shp is locked down */ 3916 static int selinux_shm_shmctl(struct shmid_kernel *shp, int cmd) 3917 { 3918 int perms; 3919 int err; 3920 3921 switch(cmd) { 3922 case IPC_INFO: 3923 case SHM_INFO: 3924 /* No specific object, just general system-wide information. */ 3925 return task_has_system(current, SYSTEM__IPC_INFO); 3926 case IPC_STAT: 3927 case SHM_STAT: 3928 perms = SHM__GETATTR | SHM__ASSOCIATE; 3929 break; 3930 case IPC_SET: 3931 perms = SHM__SETATTR; 3932 break; 3933 case SHM_LOCK: 3934 case SHM_UNLOCK: 3935 perms = SHM__LOCK; 3936 break; 3937 case IPC_RMID: 3938 perms = SHM__DESTROY; 3939 break; 3940 default: 3941 return 0; 3942 } 3943 3944 err = ipc_has_perm(&shp->shm_perm, perms); 3945 return err; 3946 } 3947 3948 static int selinux_shm_shmat(struct shmid_kernel *shp, 3949 char __user *shmaddr, int shmflg) 3950 { 3951 u32 perms; 3952 int rc; 3953 3954 rc = secondary_ops->shm_shmat(shp, shmaddr, shmflg); 3955 if (rc) 3956 return rc; 3957 3958 if (shmflg & SHM_RDONLY) 3959 perms = SHM__READ; 3960 else 3961 perms = SHM__READ | SHM__WRITE; 3962 3963 return ipc_has_perm(&shp->shm_perm, perms); 3964 } 3965 3966 /* Semaphore security operations */ 3967 static int selinux_sem_alloc_security(struct sem_array *sma) 3968 { 3969 struct task_security_struct *tsec; 3970 struct ipc_security_struct *isec; 3971 struct avc_audit_data ad; 3972 int rc; 3973 3974 rc = ipc_alloc_security(current, &sma->sem_perm, SECCLASS_SEM); 3975 if (rc) 3976 return rc; 3977 3978 tsec = current->security; 3979 isec = sma->sem_perm.security; 3980 3981 AVC_AUDIT_DATA_INIT(&ad, IPC); 3982 ad.u.ipc_id = sma->sem_perm.key; 3983 3984 rc = avc_has_perm(tsec->sid, isec->sid, SECCLASS_SEM, 3985 SEM__CREATE, &ad); 3986 if (rc) { 3987 ipc_free_security(&sma->sem_perm); 3988 return rc; 3989 } 3990 return 0; 3991 } 3992 3993 static void selinux_sem_free_security(struct sem_array *sma) 3994 { 3995 ipc_free_security(&sma->sem_perm); 3996 } 3997 3998 static int selinux_sem_associate(struct sem_array *sma, int semflg) 3999 { 4000 struct task_security_struct *tsec; 4001 struct ipc_security_struct *isec; 4002 struct avc_audit_data ad; 4003 4004 tsec = current->security; 4005 isec = sma->sem_perm.security; 4006 4007 AVC_AUDIT_DATA_INIT(&ad, IPC); 4008 ad.u.ipc_id = sma->sem_perm.key; 4009 4010 return avc_has_perm(tsec->sid, isec->sid, SECCLASS_SEM, 4011 SEM__ASSOCIATE, &ad); 4012 } 4013 4014 /* Note, at this point, sma is locked down */ 4015 static int selinux_sem_semctl(struct sem_array *sma, int cmd) 4016 { 4017 int err; 4018 u32 perms; 4019 4020 switch(cmd) { 4021 case IPC_INFO: 4022 case SEM_INFO: 4023 /* No specific object, just general system-wide information. */ 4024 return task_has_system(current, SYSTEM__IPC_INFO); 4025 case GETPID: 4026 case GETNCNT: 4027 case GETZCNT: 4028 perms = SEM__GETATTR; 4029 break; 4030 case GETVAL: 4031 case GETALL: 4032 perms = SEM__READ; 4033 break; 4034 case SETVAL: 4035 case SETALL: 4036 perms = SEM__WRITE; 4037 break; 4038 case IPC_RMID: 4039 perms = SEM__DESTROY; 4040 break; 4041 case IPC_SET: 4042 perms = SEM__SETATTR; 4043 break; 4044 case IPC_STAT: 4045 case SEM_STAT: 4046 perms = SEM__GETATTR | SEM__ASSOCIATE; 4047 break; 4048 default: 4049 return 0; 4050 } 4051 4052 err = ipc_has_perm(&sma->sem_perm, perms); 4053 return err; 4054 } 4055 4056 static int selinux_sem_semop(struct sem_array *sma, 4057 struct sembuf *sops, unsigned nsops, int alter) 4058 { 4059 u32 perms; 4060 4061 if (alter) 4062 perms = SEM__READ | SEM__WRITE; 4063 else 4064 perms = SEM__READ; 4065 4066 return ipc_has_perm(&sma->sem_perm, perms); 4067 } 4068 4069 static int selinux_ipc_permission(struct kern_ipc_perm *ipcp, short flag) 4070 { 4071 u32 av = 0; 4072 4073 av = 0; 4074 if (flag & S_IRUGO) 4075 av |= IPC__UNIX_READ; 4076 if (flag & S_IWUGO) 4077 av |= IPC__UNIX_WRITE; 4078 4079 if (av == 0) 4080 return 0; 4081 4082 return ipc_has_perm(ipcp, av); 4083 } 4084 4085 /* module stacking operations */ 4086 static int selinux_register_security (const char *name, struct security_operations *ops) 4087 { 4088 if (secondary_ops != original_ops) { 4089 printk(KERN_INFO "%s: There is already a secondary security " 4090 "module registered.\n", __FUNCTION__); 4091 return -EINVAL; 4092 } 4093 4094 secondary_ops = ops; 4095 4096 printk(KERN_INFO "%s: Registering secondary module %s\n", 4097 __FUNCTION__, 4098 name); 4099 4100 return 0; 4101 } 4102 4103 static int selinux_unregister_security (const char *name, struct security_operations *ops) 4104 { 4105 if (ops != secondary_ops) { 4106 printk (KERN_INFO "%s: trying to unregister a security module " 4107 "that is not registered.\n", __FUNCTION__); 4108 return -EINVAL; 4109 } 4110 4111 secondary_ops = original_ops; 4112 4113 return 0; 4114 } 4115 4116 static void selinux_d_instantiate (struct dentry *dentry, struct inode *inode) 4117 { 4118 if (inode) 4119 inode_doinit_with_dentry(inode, dentry); 4120 } 4121 4122 static int selinux_getprocattr(struct task_struct *p, 4123 char *name, void *value, size_t size) 4124 { 4125 struct task_security_struct *tsec; 4126 u32 sid, len; 4127 char *context; 4128 int error; 4129 4130 if (current != p) { 4131 error = task_has_perm(current, p, PROCESS__GETATTR); 4132 if (error) 4133 return error; 4134 } 4135 4136 if (!size) 4137 return -ERANGE; 4138 4139 tsec = p->security; 4140 4141 if (!strcmp(name, "current")) 4142 sid = tsec->sid; 4143 else if (!strcmp(name, "prev")) 4144 sid = tsec->osid; 4145 else if (!strcmp(name, "exec")) 4146 sid = tsec->exec_sid; 4147 else if (!strcmp(name, "fscreate")) 4148 sid = tsec->create_sid; 4149 else 4150 return -EINVAL; 4151 4152 if (!sid) 4153 return 0; 4154 4155 error = security_sid_to_context(sid, &context, &len); 4156 if (error) 4157 return error; 4158 if (len > size) { 4159 kfree(context); 4160 return -ERANGE; 4161 } 4162 memcpy(value, context, len); 4163 kfree(context); 4164 return len; 4165 } 4166 4167 static int selinux_setprocattr(struct task_struct *p, 4168 char *name, void *value, size_t size) 4169 { 4170 struct task_security_struct *tsec; 4171 u32 sid = 0; 4172 int error; 4173 char *str = value; 4174 4175 if (current != p) { 4176 /* SELinux only allows a process to change its own 4177 security attributes. */ 4178 return -EACCES; 4179 } 4180 4181 /* 4182 * Basic control over ability to set these attributes at all. 4183 * current == p, but we'll pass them separately in case the 4184 * above restriction is ever removed. 4185 */ 4186 if (!strcmp(name, "exec")) 4187 error = task_has_perm(current, p, PROCESS__SETEXEC); 4188 else if (!strcmp(name, "fscreate")) 4189 error = task_has_perm(current, p, PROCESS__SETFSCREATE); 4190 else if (!strcmp(name, "current")) 4191 error = task_has_perm(current, p, PROCESS__SETCURRENT); 4192 else 4193 error = -EINVAL; 4194 if (error) 4195 return error; 4196 4197 /* Obtain a SID for the context, if one was specified. */ 4198 if (size && str[1] && str[1] != '\n') { 4199 if (str[size-1] == '\n') { 4200 str[size-1] = 0; 4201 size--; 4202 } 4203 error = security_context_to_sid(value, size, &sid); 4204 if (error) 4205 return error; 4206 } 4207 4208 /* Permission checking based on the specified context is 4209 performed during the actual operation (execve, 4210 open/mkdir/...), when we know the full context of the 4211 operation. See selinux_bprm_set_security for the execve 4212 checks and may_create for the file creation checks. The 4213 operation will then fail if the context is not permitted. */ 4214 tsec = p->security; 4215 if (!strcmp(name, "exec")) 4216 tsec->exec_sid = sid; 4217 else if (!strcmp(name, "fscreate")) 4218 tsec->create_sid = sid; 4219 else if (!strcmp(name, "current")) { 4220 struct av_decision avd; 4221 4222 if (sid == 0) 4223 return -EINVAL; 4224 4225 /* Only allow single threaded processes to change context */ 4226 if (atomic_read(&p->mm->mm_users) != 1) { 4227 struct task_struct *g, *t; 4228 struct mm_struct *mm = p->mm; 4229 read_lock(&tasklist_lock); 4230 do_each_thread(g, t) 4231 if (t->mm == mm && t != p) { 4232 read_unlock(&tasklist_lock); 4233 return -EPERM; 4234 } 4235 while_each_thread(g, t); 4236 read_unlock(&tasklist_lock); 4237 } 4238 4239 /* Check permissions for the transition. */ 4240 error = avc_has_perm(tsec->sid, sid, SECCLASS_PROCESS, 4241 PROCESS__DYNTRANSITION, NULL); 4242 if (error) 4243 return error; 4244 4245 /* Check for ptracing, and update the task SID if ok. 4246 Otherwise, leave SID unchanged and fail. */ 4247 task_lock(p); 4248 if (p->ptrace & PT_PTRACED) { 4249 error = avc_has_perm_noaudit(tsec->ptrace_sid, sid, 4250 SECCLASS_PROCESS, 4251 PROCESS__PTRACE, &avd); 4252 if (!error) 4253 tsec->sid = sid; 4254 task_unlock(p); 4255 avc_audit(tsec->ptrace_sid, sid, SECCLASS_PROCESS, 4256 PROCESS__PTRACE, &avd, error, NULL); 4257 if (error) 4258 return error; 4259 } else { 4260 tsec->sid = sid; 4261 task_unlock(p); 4262 } 4263 } 4264 else 4265 return -EINVAL; 4266 4267 return size; 4268 } 4269 4270 static struct security_operations selinux_ops = { 4271 .ptrace = selinux_ptrace, 4272 .capget = selinux_capget, 4273 .capset_check = selinux_capset_check, 4274 .capset_set = selinux_capset_set, 4275 .sysctl = selinux_sysctl, 4276 .capable = selinux_capable, 4277 .quotactl = selinux_quotactl, 4278 .quota_on = selinux_quota_on, 4279 .syslog = selinux_syslog, 4280 .vm_enough_memory = selinux_vm_enough_memory, 4281 4282 .netlink_send = selinux_netlink_send, 4283 .netlink_recv = selinux_netlink_recv, 4284 4285 .bprm_alloc_security = selinux_bprm_alloc_security, 4286 .bprm_free_security = selinux_bprm_free_security, 4287 .bprm_apply_creds = selinux_bprm_apply_creds, 4288 .bprm_post_apply_creds = selinux_bprm_post_apply_creds, 4289 .bprm_set_security = selinux_bprm_set_security, 4290 .bprm_check_security = selinux_bprm_check_security, 4291 .bprm_secureexec = selinux_bprm_secureexec, 4292 4293 .sb_alloc_security = selinux_sb_alloc_security, 4294 .sb_free_security = selinux_sb_free_security, 4295 .sb_copy_data = selinux_sb_copy_data, 4296 .sb_kern_mount = selinux_sb_kern_mount, 4297 .sb_statfs = selinux_sb_statfs, 4298 .sb_mount = selinux_mount, 4299 .sb_umount = selinux_umount, 4300 4301 .inode_alloc_security = selinux_inode_alloc_security, 4302 .inode_free_security = selinux_inode_free_security, 4303 .inode_init_security = selinux_inode_init_security, 4304 .inode_create = selinux_inode_create, 4305 .inode_link = selinux_inode_link, 4306 .inode_unlink = selinux_inode_unlink, 4307 .inode_symlink = selinux_inode_symlink, 4308 .inode_mkdir = selinux_inode_mkdir, 4309 .inode_rmdir = selinux_inode_rmdir, 4310 .inode_mknod = selinux_inode_mknod, 4311 .inode_rename = selinux_inode_rename, 4312 .inode_readlink = selinux_inode_readlink, 4313 .inode_follow_link = selinux_inode_follow_link, 4314 .inode_permission = selinux_inode_permission, 4315 .inode_setattr = selinux_inode_setattr, 4316 .inode_getattr = selinux_inode_getattr, 4317 .inode_setxattr = selinux_inode_setxattr, 4318 .inode_post_setxattr = selinux_inode_post_setxattr, 4319 .inode_getxattr = selinux_inode_getxattr, 4320 .inode_listxattr = selinux_inode_listxattr, 4321 .inode_removexattr = selinux_inode_removexattr, 4322 .inode_getsecurity = selinux_inode_getsecurity, 4323 .inode_setsecurity = selinux_inode_setsecurity, 4324 .inode_listsecurity = selinux_inode_listsecurity, 4325 4326 .file_permission = selinux_file_permission, 4327 .file_alloc_security = selinux_file_alloc_security, 4328 .file_free_security = selinux_file_free_security, 4329 .file_ioctl = selinux_file_ioctl, 4330 .file_mmap = selinux_file_mmap, 4331 .file_mprotect = selinux_file_mprotect, 4332 .file_lock = selinux_file_lock, 4333 .file_fcntl = selinux_file_fcntl, 4334 .file_set_fowner = selinux_file_set_fowner, 4335 .file_send_sigiotask = selinux_file_send_sigiotask, 4336 .file_receive = selinux_file_receive, 4337 4338 .task_create = selinux_task_create, 4339 .task_alloc_security = selinux_task_alloc_security, 4340 .task_free_security = selinux_task_free_security, 4341 .task_setuid = selinux_task_setuid, 4342 .task_post_setuid = selinux_task_post_setuid, 4343 .task_setgid = selinux_task_setgid, 4344 .task_setpgid = selinux_task_setpgid, 4345 .task_getpgid = selinux_task_getpgid, 4346 .task_getsid = selinux_task_getsid, 4347 .task_setgroups = selinux_task_setgroups, 4348 .task_setnice = selinux_task_setnice, 4349 .task_setrlimit = selinux_task_setrlimit, 4350 .task_setscheduler = selinux_task_setscheduler, 4351 .task_getscheduler = selinux_task_getscheduler, 4352 .task_kill = selinux_task_kill, 4353 .task_wait = selinux_task_wait, 4354 .task_prctl = selinux_task_prctl, 4355 .task_reparent_to_init = selinux_task_reparent_to_init, 4356 .task_to_inode = selinux_task_to_inode, 4357 4358 .ipc_permission = selinux_ipc_permission, 4359 4360 .msg_msg_alloc_security = selinux_msg_msg_alloc_security, 4361 .msg_msg_free_security = selinux_msg_msg_free_security, 4362 4363 .msg_queue_alloc_security = selinux_msg_queue_alloc_security, 4364 .msg_queue_free_security = selinux_msg_queue_free_security, 4365 .msg_queue_associate = selinux_msg_queue_associate, 4366 .msg_queue_msgctl = selinux_msg_queue_msgctl, 4367 .msg_queue_msgsnd = selinux_msg_queue_msgsnd, 4368 .msg_queue_msgrcv = selinux_msg_queue_msgrcv, 4369 4370 .shm_alloc_security = selinux_shm_alloc_security, 4371 .shm_free_security = selinux_shm_free_security, 4372 .shm_associate = selinux_shm_associate, 4373 .shm_shmctl = selinux_shm_shmctl, 4374 .shm_shmat = selinux_shm_shmat, 4375 4376 .sem_alloc_security = selinux_sem_alloc_security, 4377 .sem_free_security = selinux_sem_free_security, 4378 .sem_associate = selinux_sem_associate, 4379 .sem_semctl = selinux_sem_semctl, 4380 .sem_semop = selinux_sem_semop, 4381 4382 .register_security = selinux_register_security, 4383 .unregister_security = selinux_unregister_security, 4384 4385 .d_instantiate = selinux_d_instantiate, 4386 4387 .getprocattr = selinux_getprocattr, 4388 .setprocattr = selinux_setprocattr, 4389 4390 #ifdef CONFIG_SECURITY_NETWORK 4391 .unix_stream_connect = selinux_socket_unix_stream_connect, 4392 .unix_may_send = selinux_socket_unix_may_send, 4393 4394 .socket_create = selinux_socket_create, 4395 .socket_post_create = selinux_socket_post_create, 4396 .socket_bind = selinux_socket_bind, 4397 .socket_connect = selinux_socket_connect, 4398 .socket_listen = selinux_socket_listen, 4399 .socket_accept = selinux_socket_accept, 4400 .socket_sendmsg = selinux_socket_sendmsg, 4401 .socket_recvmsg = selinux_socket_recvmsg, 4402 .socket_getsockname = selinux_socket_getsockname, 4403 .socket_getpeername = selinux_socket_getpeername, 4404 .socket_getsockopt = selinux_socket_getsockopt, 4405 .socket_setsockopt = selinux_socket_setsockopt, 4406 .socket_shutdown = selinux_socket_shutdown, 4407 .socket_sock_rcv_skb = selinux_socket_sock_rcv_skb, 4408 .socket_getpeersec = selinux_socket_getpeersec, 4409 .sk_alloc_security = selinux_sk_alloc_security, 4410 .sk_free_security = selinux_sk_free_security, 4411 .sk_getsid = selinux_sk_getsid_security, 4412 #endif 4413 4414 #ifdef CONFIG_SECURITY_NETWORK_XFRM 4415 .xfrm_policy_alloc_security = selinux_xfrm_policy_alloc, 4416 .xfrm_policy_clone_security = selinux_xfrm_policy_clone, 4417 .xfrm_policy_free_security = selinux_xfrm_policy_free, 4418 .xfrm_state_alloc_security = selinux_xfrm_state_alloc, 4419 .xfrm_state_free_security = selinux_xfrm_state_free, 4420 .xfrm_policy_lookup = selinux_xfrm_policy_lookup, 4421 #endif 4422 }; 4423 4424 static __init int selinux_init(void) 4425 { 4426 struct task_security_struct *tsec; 4427 4428 if (!selinux_enabled) { 4429 printk(KERN_INFO "SELinux: Disabled at boot.\n"); 4430 return 0; 4431 } 4432 4433 printk(KERN_INFO "SELinux: Initializing.\n"); 4434 4435 /* Set the security state for the initial task. */ 4436 if (task_alloc_security(current)) 4437 panic("SELinux: Failed to initialize initial task.\n"); 4438 tsec = current->security; 4439 tsec->osid = tsec->sid = SECINITSID_KERNEL; 4440 4441 avc_init(); 4442 4443 original_ops = secondary_ops = security_ops; 4444 if (!secondary_ops) 4445 panic ("SELinux: No initial security operations\n"); 4446 if (register_security (&selinux_ops)) 4447 panic("SELinux: Unable to register with kernel.\n"); 4448 4449 if (selinux_enforcing) { 4450 printk(KERN_INFO "SELinux: Starting in enforcing mode\n"); 4451 } else { 4452 printk(KERN_INFO "SELinux: Starting in permissive mode\n"); 4453 } 4454 return 0; 4455 } 4456 4457 void selinux_complete_init(void) 4458 { 4459 printk(KERN_INFO "SELinux: Completing initialization.\n"); 4460 4461 /* Set up any superblocks initialized prior to the policy load. */ 4462 printk(KERN_INFO "SELinux: Setting up existing superblocks.\n"); 4463 spin_lock(&sb_security_lock); 4464 next_sb: 4465 if (!list_empty(&superblock_security_head)) { 4466 struct superblock_security_struct *sbsec = 4467 list_entry(superblock_security_head.next, 4468 struct superblock_security_struct, 4469 list); 4470 struct super_block *sb = sbsec->sb; 4471 spin_lock(&sb_lock); 4472 sb->s_count++; 4473 spin_unlock(&sb_lock); 4474 spin_unlock(&sb_security_lock); 4475 down_read(&sb->s_umount); 4476 if (sb->s_root) 4477 superblock_doinit(sb, NULL); 4478 drop_super(sb); 4479 spin_lock(&sb_security_lock); 4480 list_del_init(&sbsec->list); 4481 goto next_sb; 4482 } 4483 spin_unlock(&sb_security_lock); 4484 } 4485 4486 /* SELinux requires early initialization in order to label 4487 all processes and objects when they are created. */ 4488 security_initcall(selinux_init); 4489 4490 #if defined(CONFIG_SECURITY_NETWORK) && defined(CONFIG_NETFILTER) 4491 4492 static struct nf_hook_ops selinux_ipv4_op = { 4493 .hook = selinux_ipv4_postroute_last, 4494 .owner = THIS_MODULE, 4495 .pf = PF_INET, 4496 .hooknum = NF_IP_POST_ROUTING, 4497 .priority = NF_IP_PRI_SELINUX_LAST, 4498 }; 4499 4500 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE) 4501 4502 static struct nf_hook_ops selinux_ipv6_op = { 4503 .hook = selinux_ipv6_postroute_last, 4504 .owner = THIS_MODULE, 4505 .pf = PF_INET6, 4506 .hooknum = NF_IP6_POST_ROUTING, 4507 .priority = NF_IP6_PRI_SELINUX_LAST, 4508 }; 4509 4510 #endif /* IPV6 */ 4511 4512 static int __init selinux_nf_ip_init(void) 4513 { 4514 int err = 0; 4515 4516 if (!selinux_enabled) 4517 goto out; 4518 4519 printk(KERN_INFO "SELinux: Registering netfilter hooks\n"); 4520 4521 err = nf_register_hook(&selinux_ipv4_op); 4522 if (err) 4523 panic("SELinux: nf_register_hook for IPv4: error %d\n", err); 4524 4525 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE) 4526 4527 err = nf_register_hook(&selinux_ipv6_op); 4528 if (err) 4529 panic("SELinux: nf_register_hook for IPv6: error %d\n", err); 4530 4531 #endif /* IPV6 */ 4532 4533 out: 4534 return err; 4535 } 4536 4537 __initcall(selinux_nf_ip_init); 4538 4539 #ifdef CONFIG_SECURITY_SELINUX_DISABLE 4540 static void selinux_nf_ip_exit(void) 4541 { 4542 printk(KERN_INFO "SELinux: Unregistering netfilter hooks\n"); 4543 4544 nf_unregister_hook(&selinux_ipv4_op); 4545 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE) 4546 nf_unregister_hook(&selinux_ipv6_op); 4547 #endif /* IPV6 */ 4548 } 4549 #endif 4550 4551 #else /* CONFIG_SECURITY_NETWORK && CONFIG_NETFILTER */ 4552 4553 #ifdef CONFIG_SECURITY_SELINUX_DISABLE 4554 #define selinux_nf_ip_exit() 4555 #endif 4556 4557 #endif /* CONFIG_SECURITY_NETWORK && CONFIG_NETFILTER */ 4558 4559 #ifdef CONFIG_SECURITY_SELINUX_DISABLE 4560 int selinux_disable(void) 4561 { 4562 extern void exit_sel_fs(void); 4563 static int selinux_disabled = 0; 4564 4565 if (ss_initialized) { 4566 /* Not permitted after initial policy load. */ 4567 return -EINVAL; 4568 } 4569 4570 if (selinux_disabled) { 4571 /* Only do this once. */ 4572 return -EINVAL; 4573 } 4574 4575 printk(KERN_INFO "SELinux: Disabled at runtime.\n"); 4576 4577 selinux_disabled = 1; 4578 4579 /* Reset security_ops to the secondary module, dummy or capability. */ 4580 security_ops = secondary_ops; 4581 4582 /* Unregister netfilter hooks. */ 4583 selinux_nf_ip_exit(); 4584 4585 /* Unregister selinuxfs. */ 4586 exit_sel_fs(); 4587 4588 return 0; 4589 } 4590 #endif 4591 4592 4593