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