1 /* 2 * NSA Security-Enhanced Linux (SELinux) security module 3 * 4 * This file contains the SELinux hook function implementations. 5 * 6 * Authors: Stephen Smalley, <sds@epoch.ncsc.mil> 7 * Chris Vance, <cvance@nai.com> 8 * Wayne Salamon, <wsalamon@nai.com> 9 * James Morris <jmorris@redhat.com> 10 * 11 * Copyright (C) 2001,2002 Networks Associates Technology, Inc. 12 * Copyright (C) 2003 Red Hat, Inc., James Morris <jmorris@redhat.com> 13 * Copyright (C) 2004-2005 Trusted Computer Solutions, Inc. 14 * <dgoeddel@trustedcs.com> 15 * 16 * This program is free software; you can redistribute it and/or modify 17 * it under the terms of the GNU General Public License version 2, 18 * as published by the Free Software Foundation. 19 */ 20 21 #include <linux/config.h> 22 #include <linux/module.h> 23 #include <linux/init.h> 24 #include <linux/kernel.h> 25 #include <linux/ptrace.h> 26 #include <linux/errno.h> 27 #include <linux/sched.h> 28 #include <linux/security.h> 29 #include <linux/xattr.h> 30 #include <linux/capability.h> 31 #include <linux/unistd.h> 32 #include <linux/mm.h> 33 #include <linux/mman.h> 34 #include <linux/slab.h> 35 #include <linux/pagemap.h> 36 #include <linux/swap.h> 37 #include <linux/smp_lock.h> 38 #include <linux/spinlock.h> 39 #include <linux/syscalls.h> 40 #include <linux/file.h> 41 #include <linux/namei.h> 42 #include <linux/mount.h> 43 #include <linux/ext2_fs.h> 44 #include <linux/proc_fs.h> 45 #include <linux/kd.h> 46 #include <linux/netfilter_ipv4.h> 47 #include <linux/netfilter_ipv6.h> 48 #include <linux/tty.h> 49 #include <net/icmp.h> 50 #include <net/ip.h> /* for sysctl_local_port_range[] */ 51 #include <net/tcp.h> /* struct or_callable used in sock_rcv_skb */ 52 #include <asm/uaccess.h> 53 #include <asm/semaphore.h> 54 #include <asm/ioctls.h> 55 #include <linux/bitops.h> 56 #include <linux/interrupt.h> 57 #include <linux/netdevice.h> /* for network interface checks */ 58 #include <linux/netlink.h> 59 #include <linux/tcp.h> 60 #include <linux/udp.h> 61 #include <linux/quota.h> 62 #include <linux/un.h> /* for Unix socket types */ 63 #include <net/af_unix.h> /* for Unix socket types */ 64 #include <linux/parser.h> 65 #include <linux/nfs_mount.h> 66 #include <net/ipv6.h> 67 #include <linux/hugetlb.h> 68 #include <linux/personality.h> 69 #include <linux/sysctl.h> 70 #include <linux/audit.h> 71 #include <linux/string.h> 72 73 #include "avc.h" 74 #include "objsec.h" 75 #include "netif.h" 76 #include "xfrm.h" 77 78 #define XATTR_SELINUX_SUFFIX "selinux" 79 #define XATTR_NAME_SELINUX XATTR_SECURITY_PREFIX XATTR_SELINUX_SUFFIX 80 81 extern unsigned int policydb_loaded_version; 82 extern int selinux_nlmsg_lookup(u16 sclass, u16 nlmsg_type, u32 *perm); 83 84 #ifdef CONFIG_SECURITY_SELINUX_DEVELOP 85 int selinux_enforcing = 0; 86 87 static int __init enforcing_setup(char *str) 88 { 89 selinux_enforcing = simple_strtol(str,NULL,0); 90 return 1; 91 } 92 __setup("enforcing=", enforcing_setup); 93 #endif 94 95 #ifdef CONFIG_SECURITY_SELINUX_BOOTPARAM 96 int selinux_enabled = CONFIG_SECURITY_SELINUX_BOOTPARAM_VALUE; 97 98 static int __init selinux_enabled_setup(char *str) 99 { 100 selinux_enabled = simple_strtol(str, NULL, 0); 101 return 1; 102 } 103 __setup("selinux=", selinux_enabled_setup); 104 #endif 105 106 /* Original (dummy) security module. */ 107 static struct security_operations *original_ops = NULL; 108 109 /* Minimal support for a secondary security module, 110 just to allow the use of the dummy or capability modules. 111 The owlsm module can alternatively be used as a secondary 112 module as long as CONFIG_OWLSM_FD is not enabled. */ 113 static struct security_operations *secondary_ops = NULL; 114 115 /* Lists of inode and superblock security structures initialized 116 before the policy was loaded. */ 117 static LIST_HEAD(superblock_security_head); 118 static DEFINE_SPINLOCK(sb_security_lock); 119 120 static kmem_cache_t *sel_inode_cache; 121 122 /* Return security context for a given sid or just the context 123 length if the buffer is null or length is 0 */ 124 static int selinux_getsecurity(u32 sid, void *buffer, size_t size) 125 { 126 char *context; 127 unsigned len; 128 int rc; 129 130 rc = security_sid_to_context(sid, &context, &len); 131 if (rc) 132 return rc; 133 134 if (!buffer || !size) 135 goto getsecurity_exit; 136 137 if (size < len) { 138 len = -ERANGE; 139 goto getsecurity_exit; 140 } 141 memcpy(buffer, context, len); 142 143 getsecurity_exit: 144 kfree(context); 145 return len; 146 } 147 148 /* Allocate and free functions for each kind of security blob. */ 149 150 static int task_alloc_security(struct task_struct *task) 151 { 152 struct task_security_struct *tsec; 153 154 tsec = kzalloc(sizeof(struct task_security_struct), GFP_KERNEL); 155 if (!tsec) 156 return -ENOMEM; 157 158 tsec->task = task; 159 tsec->osid = tsec->sid = tsec->ptrace_sid = SECINITSID_UNLABELED; 160 task->security = tsec; 161 162 return 0; 163 } 164 165 static void task_free_security(struct task_struct *task) 166 { 167 struct task_security_struct *tsec = task->security; 168 task->security = NULL; 169 kfree(tsec); 170 } 171 172 static int inode_alloc_security(struct inode *inode) 173 { 174 struct task_security_struct *tsec = current->security; 175 struct inode_security_struct *isec; 176 177 isec = kmem_cache_alloc(sel_inode_cache, SLAB_KERNEL); 178 if (!isec) 179 return -ENOMEM; 180 181 memset(isec, 0, sizeof(*isec)); 182 init_MUTEX(&isec->sem); 183 INIT_LIST_HEAD(&isec->list); 184 isec->inode = inode; 185 isec->sid = SECINITSID_UNLABELED; 186 isec->sclass = SECCLASS_FILE; 187 isec->task_sid = tsec->sid; 188 inode->i_security = isec; 189 190 return 0; 191 } 192 193 static void inode_free_security(struct inode *inode) 194 { 195 struct inode_security_struct *isec = inode->i_security; 196 struct superblock_security_struct *sbsec = inode->i_sb->s_security; 197 198 spin_lock(&sbsec->isec_lock); 199 if (!list_empty(&isec->list)) 200 list_del_init(&isec->list); 201 spin_unlock(&sbsec->isec_lock); 202 203 inode->i_security = NULL; 204 kmem_cache_free(sel_inode_cache, isec); 205 } 206 207 static int file_alloc_security(struct file *file) 208 { 209 struct task_security_struct *tsec = current->security; 210 struct file_security_struct *fsec; 211 212 fsec = kzalloc(sizeof(struct file_security_struct), GFP_KERNEL); 213 if (!fsec) 214 return -ENOMEM; 215 216 fsec->file = file; 217 fsec->sid = tsec->sid; 218 fsec->fown_sid = tsec->sid; 219 file->f_security = fsec; 220 221 return 0; 222 } 223 224 static void file_free_security(struct file *file) 225 { 226 struct file_security_struct *fsec = file->f_security; 227 file->f_security = NULL; 228 kfree(fsec); 229 } 230 231 static int superblock_alloc_security(struct super_block *sb) 232 { 233 struct superblock_security_struct *sbsec; 234 235 sbsec = kzalloc(sizeof(struct superblock_security_struct), GFP_KERNEL); 236 if (!sbsec) 237 return -ENOMEM; 238 239 init_MUTEX(&sbsec->sem); 240 INIT_LIST_HEAD(&sbsec->list); 241 INIT_LIST_HEAD(&sbsec->isec_head); 242 spin_lock_init(&sbsec->isec_lock); 243 sbsec->sb = sb; 244 sbsec->sid = SECINITSID_UNLABELED; 245 sbsec->def_sid = SECINITSID_FILE; 246 sb->s_security = sbsec; 247 248 return 0; 249 } 250 251 static void superblock_free_security(struct super_block *sb) 252 { 253 struct superblock_security_struct *sbsec = sb->s_security; 254 255 spin_lock(&sb_security_lock); 256 if (!list_empty(&sbsec->list)) 257 list_del_init(&sbsec->list); 258 spin_unlock(&sb_security_lock); 259 260 sb->s_security = NULL; 261 kfree(sbsec); 262 } 263 264 static int sk_alloc_security(struct sock *sk, int family, gfp_t priority) 265 { 266 struct sk_security_struct *ssec; 267 268 if (family != PF_UNIX) 269 return 0; 270 271 ssec = kzalloc(sizeof(*ssec), priority); 272 if (!ssec) 273 return -ENOMEM; 274 275 ssec->sk = sk; 276 ssec->peer_sid = SECINITSID_UNLABELED; 277 sk->sk_security = ssec; 278 279 return 0; 280 } 281 282 static void sk_free_security(struct sock *sk) 283 { 284 struct sk_security_struct *ssec = sk->sk_security; 285 286 if (sk->sk_family != PF_UNIX) 287 return; 288 289 sk->sk_security = NULL; 290 kfree(ssec); 291 } 292 293 /* The security server must be initialized before 294 any labeling or access decisions can be provided. */ 295 extern int ss_initialized; 296 297 /* The file system's label must be initialized prior to use. */ 298 299 static char *labeling_behaviors[6] = { 300 "uses xattr", 301 "uses transition SIDs", 302 "uses task SIDs", 303 "uses genfs_contexts", 304 "not configured for labeling", 305 "uses mountpoint labeling", 306 }; 307 308 static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dentry); 309 310 static inline int inode_doinit(struct inode *inode) 311 { 312 return inode_doinit_with_dentry(inode, NULL); 313 } 314 315 enum { 316 Opt_context = 1, 317 Opt_fscontext = 2, 318 Opt_defcontext = 4, 319 }; 320 321 static match_table_t tokens = { 322 {Opt_context, "context=%s"}, 323 {Opt_fscontext, "fscontext=%s"}, 324 {Opt_defcontext, "defcontext=%s"}, 325 }; 326 327 #define SEL_MOUNT_FAIL_MSG "SELinux: duplicate or incompatible mount options\n" 328 329 static int try_context_mount(struct super_block *sb, void *data) 330 { 331 char *context = NULL, *defcontext = NULL; 332 const char *name; 333 u32 sid; 334 int alloc = 0, rc = 0, seen = 0; 335 struct task_security_struct *tsec = current->security; 336 struct superblock_security_struct *sbsec = sb->s_security; 337 338 if (!data) 339 goto out; 340 341 name = sb->s_type->name; 342 343 if (sb->s_type->fs_flags & FS_BINARY_MOUNTDATA) { 344 345 /* NFS we understand. */ 346 if (!strcmp(name, "nfs")) { 347 struct nfs_mount_data *d = data; 348 349 if (d->version < NFS_MOUNT_VERSION) 350 goto out; 351 352 if (d->context[0]) { 353 context = d->context; 354 seen |= Opt_context; 355 } 356 } else 357 goto out; 358 359 } else { 360 /* Standard string-based options. */ 361 char *p, *options = data; 362 363 while ((p = strsep(&options, ",")) != NULL) { 364 int token; 365 substring_t args[MAX_OPT_ARGS]; 366 367 if (!*p) 368 continue; 369 370 token = match_token(p, tokens, args); 371 372 switch (token) { 373 case Opt_context: 374 if (seen) { 375 rc = -EINVAL; 376 printk(KERN_WARNING SEL_MOUNT_FAIL_MSG); 377 goto out_free; 378 } 379 context = match_strdup(&args[0]); 380 if (!context) { 381 rc = -ENOMEM; 382 goto out_free; 383 } 384 if (!alloc) 385 alloc = 1; 386 seen |= Opt_context; 387 break; 388 389 case Opt_fscontext: 390 if (seen & (Opt_context|Opt_fscontext)) { 391 rc = -EINVAL; 392 printk(KERN_WARNING SEL_MOUNT_FAIL_MSG); 393 goto out_free; 394 } 395 context = match_strdup(&args[0]); 396 if (!context) { 397 rc = -ENOMEM; 398 goto out_free; 399 } 400 if (!alloc) 401 alloc = 1; 402 seen |= Opt_fscontext; 403 break; 404 405 case Opt_defcontext: 406 if (sbsec->behavior != SECURITY_FS_USE_XATTR) { 407 rc = -EINVAL; 408 printk(KERN_WARNING "SELinux: " 409 "defcontext option is invalid " 410 "for this filesystem type\n"); 411 goto out_free; 412 } 413 if (seen & (Opt_context|Opt_defcontext)) { 414 rc = -EINVAL; 415 printk(KERN_WARNING SEL_MOUNT_FAIL_MSG); 416 goto out_free; 417 } 418 defcontext = match_strdup(&args[0]); 419 if (!defcontext) { 420 rc = -ENOMEM; 421 goto out_free; 422 } 423 if (!alloc) 424 alloc = 1; 425 seen |= Opt_defcontext; 426 break; 427 428 default: 429 rc = -EINVAL; 430 printk(KERN_WARNING "SELinux: unknown mount " 431 "option\n"); 432 goto out_free; 433 434 } 435 } 436 } 437 438 if (!seen) 439 goto out; 440 441 if (context) { 442 rc = security_context_to_sid(context, strlen(context), &sid); 443 if (rc) { 444 printk(KERN_WARNING "SELinux: security_context_to_sid" 445 "(%s) failed for (dev %s, type %s) errno=%d\n", 446 context, sb->s_id, name, rc); 447 goto out_free; 448 } 449 450 rc = avc_has_perm(tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM, 451 FILESYSTEM__RELABELFROM, NULL); 452 if (rc) 453 goto out_free; 454 455 rc = avc_has_perm(tsec->sid, sid, SECCLASS_FILESYSTEM, 456 FILESYSTEM__RELABELTO, NULL); 457 if (rc) 458 goto out_free; 459 460 sbsec->sid = sid; 461 462 if (seen & Opt_context) 463 sbsec->behavior = SECURITY_FS_USE_MNTPOINT; 464 } 465 466 if (defcontext) { 467 rc = security_context_to_sid(defcontext, strlen(defcontext), &sid); 468 if (rc) { 469 printk(KERN_WARNING "SELinux: security_context_to_sid" 470 "(%s) failed for (dev %s, type %s) errno=%d\n", 471 defcontext, sb->s_id, name, rc); 472 goto out_free; 473 } 474 475 if (sid == sbsec->def_sid) 476 goto out_free; 477 478 rc = avc_has_perm(tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM, 479 FILESYSTEM__RELABELFROM, NULL); 480 if (rc) 481 goto out_free; 482 483 rc = avc_has_perm(sid, sbsec->sid, SECCLASS_FILESYSTEM, 484 FILESYSTEM__ASSOCIATE, NULL); 485 if (rc) 486 goto out_free; 487 488 sbsec->def_sid = sid; 489 } 490 491 out_free: 492 if (alloc) { 493 kfree(context); 494 kfree(defcontext); 495 } 496 out: 497 return rc; 498 } 499 500 static int superblock_doinit(struct super_block *sb, void *data) 501 { 502 struct superblock_security_struct *sbsec = sb->s_security; 503 struct dentry *root = sb->s_root; 504 struct inode *inode = root->d_inode; 505 int rc = 0; 506 507 down(&sbsec->sem); 508 if (sbsec->initialized) 509 goto out; 510 511 if (!ss_initialized) { 512 /* Defer initialization until selinux_complete_init, 513 after the initial policy is loaded and the security 514 server is ready to handle calls. */ 515 spin_lock(&sb_security_lock); 516 if (list_empty(&sbsec->list)) 517 list_add(&sbsec->list, &superblock_security_head); 518 spin_unlock(&sb_security_lock); 519 goto out; 520 } 521 522 /* Determine the labeling behavior to use for this filesystem type. */ 523 rc = security_fs_use(sb->s_type->name, &sbsec->behavior, &sbsec->sid); 524 if (rc) { 525 printk(KERN_WARNING "%s: security_fs_use(%s) returned %d\n", 526 __FUNCTION__, sb->s_type->name, rc); 527 goto out; 528 } 529 530 rc = try_context_mount(sb, data); 531 if (rc) 532 goto out; 533 534 if (sbsec->behavior == SECURITY_FS_USE_XATTR) { 535 /* Make sure that the xattr handler exists and that no 536 error other than -ENODATA is returned by getxattr on 537 the root directory. -ENODATA is ok, as this may be 538 the first boot of the SELinux kernel before we have 539 assigned xattr values to the filesystem. */ 540 if (!inode->i_op->getxattr) { 541 printk(KERN_WARNING "SELinux: (dev %s, type %s) has no " 542 "xattr support\n", sb->s_id, sb->s_type->name); 543 rc = -EOPNOTSUPP; 544 goto out; 545 } 546 rc = inode->i_op->getxattr(root, XATTR_NAME_SELINUX, NULL, 0); 547 if (rc < 0 && rc != -ENODATA) { 548 if (rc == -EOPNOTSUPP) 549 printk(KERN_WARNING "SELinux: (dev %s, type " 550 "%s) has no security xattr handler\n", 551 sb->s_id, sb->s_type->name); 552 else 553 printk(KERN_WARNING "SELinux: (dev %s, type " 554 "%s) getxattr errno %d\n", sb->s_id, 555 sb->s_type->name, -rc); 556 goto out; 557 } 558 } 559 560 if (strcmp(sb->s_type->name, "proc") == 0) 561 sbsec->proc = 1; 562 563 sbsec->initialized = 1; 564 565 if (sbsec->behavior > ARRAY_SIZE(labeling_behaviors)) { 566 printk(KERN_INFO "SELinux: initialized (dev %s, type %s), unknown behavior\n", 567 sb->s_id, sb->s_type->name); 568 } 569 else { 570 printk(KERN_INFO "SELinux: initialized (dev %s, type %s), %s\n", 571 sb->s_id, sb->s_type->name, 572 labeling_behaviors[sbsec->behavior-1]); 573 } 574 575 /* Initialize the root inode. */ 576 rc = inode_doinit_with_dentry(sb->s_root->d_inode, sb->s_root); 577 578 /* Initialize any other inodes associated with the superblock, e.g. 579 inodes created prior to initial policy load or inodes created 580 during get_sb by a pseudo filesystem that directly 581 populates itself. */ 582 spin_lock(&sbsec->isec_lock); 583 next_inode: 584 if (!list_empty(&sbsec->isec_head)) { 585 struct inode_security_struct *isec = 586 list_entry(sbsec->isec_head.next, 587 struct inode_security_struct, list); 588 struct inode *inode = isec->inode; 589 spin_unlock(&sbsec->isec_lock); 590 inode = igrab(inode); 591 if (inode) { 592 if (!IS_PRIVATE (inode)) 593 inode_doinit(inode); 594 iput(inode); 595 } 596 spin_lock(&sbsec->isec_lock); 597 list_del_init(&isec->list); 598 goto next_inode; 599 } 600 spin_unlock(&sbsec->isec_lock); 601 out: 602 up(&sbsec->sem); 603 return rc; 604 } 605 606 static inline u16 inode_mode_to_security_class(umode_t mode) 607 { 608 switch (mode & S_IFMT) { 609 case S_IFSOCK: 610 return SECCLASS_SOCK_FILE; 611 case S_IFLNK: 612 return SECCLASS_LNK_FILE; 613 case S_IFREG: 614 return SECCLASS_FILE; 615 case S_IFBLK: 616 return SECCLASS_BLK_FILE; 617 case S_IFDIR: 618 return SECCLASS_DIR; 619 case S_IFCHR: 620 return SECCLASS_CHR_FILE; 621 case S_IFIFO: 622 return SECCLASS_FIFO_FILE; 623 624 } 625 626 return SECCLASS_FILE; 627 } 628 629 static inline int default_protocol_stream(int protocol) 630 { 631 return (protocol == IPPROTO_IP || protocol == IPPROTO_TCP); 632 } 633 634 static inline int default_protocol_dgram(int protocol) 635 { 636 return (protocol == IPPROTO_IP || protocol == IPPROTO_UDP); 637 } 638 639 static inline u16 socket_type_to_security_class(int family, int type, int protocol) 640 { 641 switch (family) { 642 case PF_UNIX: 643 switch (type) { 644 case SOCK_STREAM: 645 case SOCK_SEQPACKET: 646 return SECCLASS_UNIX_STREAM_SOCKET; 647 case SOCK_DGRAM: 648 return SECCLASS_UNIX_DGRAM_SOCKET; 649 } 650 break; 651 case PF_INET: 652 case PF_INET6: 653 switch (type) { 654 case SOCK_STREAM: 655 if (default_protocol_stream(protocol)) 656 return SECCLASS_TCP_SOCKET; 657 else 658 return SECCLASS_RAWIP_SOCKET; 659 case SOCK_DGRAM: 660 if (default_protocol_dgram(protocol)) 661 return SECCLASS_UDP_SOCKET; 662 else 663 return SECCLASS_RAWIP_SOCKET; 664 default: 665 return SECCLASS_RAWIP_SOCKET; 666 } 667 break; 668 case PF_NETLINK: 669 switch (protocol) { 670 case NETLINK_ROUTE: 671 return SECCLASS_NETLINK_ROUTE_SOCKET; 672 case NETLINK_FIREWALL: 673 return SECCLASS_NETLINK_FIREWALL_SOCKET; 674 case NETLINK_INET_DIAG: 675 return SECCLASS_NETLINK_TCPDIAG_SOCKET; 676 case NETLINK_NFLOG: 677 return SECCLASS_NETLINK_NFLOG_SOCKET; 678 case NETLINK_XFRM: 679 return SECCLASS_NETLINK_XFRM_SOCKET; 680 case NETLINK_SELINUX: 681 return SECCLASS_NETLINK_SELINUX_SOCKET; 682 case NETLINK_AUDIT: 683 return SECCLASS_NETLINK_AUDIT_SOCKET; 684 case NETLINK_IP6_FW: 685 return SECCLASS_NETLINK_IP6FW_SOCKET; 686 case NETLINK_DNRTMSG: 687 return SECCLASS_NETLINK_DNRT_SOCKET; 688 case NETLINK_KOBJECT_UEVENT: 689 return SECCLASS_NETLINK_KOBJECT_UEVENT_SOCKET; 690 default: 691 return SECCLASS_NETLINK_SOCKET; 692 } 693 case PF_PACKET: 694 return SECCLASS_PACKET_SOCKET; 695 case PF_KEY: 696 return SECCLASS_KEY_SOCKET; 697 } 698 699 return SECCLASS_SOCKET; 700 } 701 702 #ifdef CONFIG_PROC_FS 703 static int selinux_proc_get_sid(struct proc_dir_entry *de, 704 u16 tclass, 705 u32 *sid) 706 { 707 int buflen, rc; 708 char *buffer, *path, *end; 709 710 buffer = (char*)__get_free_page(GFP_KERNEL); 711 if (!buffer) 712 return -ENOMEM; 713 714 buflen = PAGE_SIZE; 715 end = buffer+buflen; 716 *--end = '\0'; 717 buflen--; 718 path = end-1; 719 *path = '/'; 720 while (de && de != de->parent) { 721 buflen -= de->namelen + 1; 722 if (buflen < 0) 723 break; 724 end -= de->namelen; 725 memcpy(end, de->name, de->namelen); 726 *--end = '/'; 727 path = end; 728 de = de->parent; 729 } 730 rc = security_genfs_sid("proc", path, tclass, sid); 731 free_page((unsigned long)buffer); 732 return rc; 733 } 734 #else 735 static int selinux_proc_get_sid(struct proc_dir_entry *de, 736 u16 tclass, 737 u32 *sid) 738 { 739 return -EINVAL; 740 } 741 #endif 742 743 /* The inode's security attributes must be initialized before first use. */ 744 static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dentry) 745 { 746 struct superblock_security_struct *sbsec = NULL; 747 struct inode_security_struct *isec = inode->i_security; 748 u32 sid; 749 struct dentry *dentry; 750 #define INITCONTEXTLEN 255 751 char *context = NULL; 752 unsigned len = 0; 753 int rc = 0; 754 int hold_sem = 0; 755 756 if (isec->initialized) 757 goto out; 758 759 down(&isec->sem); 760 hold_sem = 1; 761 if (isec->initialized) 762 goto out; 763 764 sbsec = inode->i_sb->s_security; 765 if (!sbsec->initialized) { 766 /* Defer initialization until selinux_complete_init, 767 after the initial policy is loaded and the security 768 server is ready to handle calls. */ 769 spin_lock(&sbsec->isec_lock); 770 if (list_empty(&isec->list)) 771 list_add(&isec->list, &sbsec->isec_head); 772 spin_unlock(&sbsec->isec_lock); 773 goto out; 774 } 775 776 switch (sbsec->behavior) { 777 case SECURITY_FS_USE_XATTR: 778 if (!inode->i_op->getxattr) { 779 isec->sid = sbsec->def_sid; 780 break; 781 } 782 783 /* Need a dentry, since the xattr API requires one. 784 Life would be simpler if we could just pass the inode. */ 785 if (opt_dentry) { 786 /* Called from d_instantiate or d_splice_alias. */ 787 dentry = dget(opt_dentry); 788 } else { 789 /* Called from selinux_complete_init, try to find a dentry. */ 790 dentry = d_find_alias(inode); 791 } 792 if (!dentry) { 793 printk(KERN_WARNING "%s: no dentry for dev=%s " 794 "ino=%ld\n", __FUNCTION__, inode->i_sb->s_id, 795 inode->i_ino); 796 goto out; 797 } 798 799 len = INITCONTEXTLEN; 800 context = kmalloc(len, GFP_KERNEL); 801 if (!context) { 802 rc = -ENOMEM; 803 dput(dentry); 804 goto out; 805 } 806 rc = inode->i_op->getxattr(dentry, XATTR_NAME_SELINUX, 807 context, len); 808 if (rc == -ERANGE) { 809 /* Need a larger buffer. Query for the right size. */ 810 rc = inode->i_op->getxattr(dentry, XATTR_NAME_SELINUX, 811 NULL, 0); 812 if (rc < 0) { 813 dput(dentry); 814 goto out; 815 } 816 kfree(context); 817 len = rc; 818 context = kmalloc(len, GFP_KERNEL); 819 if (!context) { 820 rc = -ENOMEM; 821 dput(dentry); 822 goto out; 823 } 824 rc = inode->i_op->getxattr(dentry, 825 XATTR_NAME_SELINUX, 826 context, len); 827 } 828 dput(dentry); 829 if (rc < 0) { 830 if (rc != -ENODATA) { 831 printk(KERN_WARNING "%s: getxattr returned " 832 "%d for dev=%s ino=%ld\n", __FUNCTION__, 833 -rc, inode->i_sb->s_id, inode->i_ino); 834 kfree(context); 835 goto out; 836 } 837 /* Map ENODATA to the default file SID */ 838 sid = sbsec->def_sid; 839 rc = 0; 840 } else { 841 rc = security_context_to_sid_default(context, rc, &sid, 842 sbsec->def_sid); 843 if (rc) { 844 printk(KERN_WARNING "%s: context_to_sid(%s) " 845 "returned %d for dev=%s ino=%ld\n", 846 __FUNCTION__, context, -rc, 847 inode->i_sb->s_id, inode->i_ino); 848 kfree(context); 849 /* Leave with the unlabeled SID */ 850 rc = 0; 851 break; 852 } 853 } 854 kfree(context); 855 isec->sid = sid; 856 break; 857 case SECURITY_FS_USE_TASK: 858 isec->sid = isec->task_sid; 859 break; 860 case SECURITY_FS_USE_TRANS: 861 /* Default to the fs SID. */ 862 isec->sid = sbsec->sid; 863 864 /* Try to obtain a transition SID. */ 865 isec->sclass = inode_mode_to_security_class(inode->i_mode); 866 rc = security_transition_sid(isec->task_sid, 867 sbsec->sid, 868 isec->sclass, 869 &sid); 870 if (rc) 871 goto out; 872 isec->sid = sid; 873 break; 874 default: 875 /* Default to the fs SID. */ 876 isec->sid = sbsec->sid; 877 878 if (sbsec->proc) { 879 struct proc_inode *proci = PROC_I(inode); 880 if (proci->pde) { 881 isec->sclass = inode_mode_to_security_class(inode->i_mode); 882 rc = selinux_proc_get_sid(proci->pde, 883 isec->sclass, 884 &sid); 885 if (rc) 886 goto out; 887 isec->sid = sid; 888 } 889 } 890 break; 891 } 892 893 isec->initialized = 1; 894 895 out: 896 if (isec->sclass == SECCLASS_FILE) 897 isec->sclass = inode_mode_to_security_class(inode->i_mode); 898 899 if (hold_sem) 900 up(&isec->sem); 901 return rc; 902 } 903 904 /* Convert a Linux signal to an access vector. */ 905 static inline u32 signal_to_av(int sig) 906 { 907 u32 perm = 0; 908 909 switch (sig) { 910 case SIGCHLD: 911 /* Commonly granted from child to parent. */ 912 perm = PROCESS__SIGCHLD; 913 break; 914 case SIGKILL: 915 /* Cannot be caught or ignored */ 916 perm = PROCESS__SIGKILL; 917 break; 918 case SIGSTOP: 919 /* Cannot be caught or ignored */ 920 perm = PROCESS__SIGSTOP; 921 break; 922 default: 923 /* All other signals. */ 924 perm = PROCESS__SIGNAL; 925 break; 926 } 927 928 return perm; 929 } 930 931 /* Check permission betweeen a pair of tasks, e.g. signal checks, 932 fork check, ptrace check, etc. */ 933 static int task_has_perm(struct task_struct *tsk1, 934 struct task_struct *tsk2, 935 u32 perms) 936 { 937 struct task_security_struct *tsec1, *tsec2; 938 939 tsec1 = tsk1->security; 940 tsec2 = tsk2->security; 941 return avc_has_perm(tsec1->sid, tsec2->sid, 942 SECCLASS_PROCESS, perms, NULL); 943 } 944 945 /* Check whether a task is allowed to use a capability. */ 946 static int task_has_capability(struct task_struct *tsk, 947 int cap) 948 { 949 struct task_security_struct *tsec; 950 struct avc_audit_data ad; 951 952 tsec = tsk->security; 953 954 AVC_AUDIT_DATA_INIT(&ad,CAP); 955 ad.tsk = tsk; 956 ad.u.cap = cap; 957 958 return avc_has_perm(tsec->sid, tsec->sid, 959 SECCLASS_CAPABILITY, CAP_TO_MASK(cap), &ad); 960 } 961 962 /* Check whether a task is allowed to use a system operation. */ 963 static int task_has_system(struct task_struct *tsk, 964 u32 perms) 965 { 966 struct task_security_struct *tsec; 967 968 tsec = tsk->security; 969 970 return avc_has_perm(tsec->sid, SECINITSID_KERNEL, 971 SECCLASS_SYSTEM, perms, NULL); 972 } 973 974 /* Check whether a task has a particular permission to an inode. 975 The 'adp' parameter is optional and allows other audit 976 data to be passed (e.g. the dentry). */ 977 static int inode_has_perm(struct task_struct *tsk, 978 struct inode *inode, 979 u32 perms, 980 struct avc_audit_data *adp) 981 { 982 struct task_security_struct *tsec; 983 struct inode_security_struct *isec; 984 struct avc_audit_data ad; 985 986 tsec = tsk->security; 987 isec = inode->i_security; 988 989 if (!adp) { 990 adp = &ad; 991 AVC_AUDIT_DATA_INIT(&ad, FS); 992 ad.u.fs.inode = inode; 993 } 994 995 return avc_has_perm(tsec->sid, isec->sid, isec->sclass, perms, adp); 996 } 997 998 /* Same as inode_has_perm, but pass explicit audit data containing 999 the dentry to help the auditing code to more easily generate the 1000 pathname if needed. */ 1001 static inline int dentry_has_perm(struct task_struct *tsk, 1002 struct vfsmount *mnt, 1003 struct dentry *dentry, 1004 u32 av) 1005 { 1006 struct inode *inode = dentry->d_inode; 1007 struct avc_audit_data ad; 1008 AVC_AUDIT_DATA_INIT(&ad,FS); 1009 ad.u.fs.mnt = mnt; 1010 ad.u.fs.dentry = dentry; 1011 return inode_has_perm(tsk, inode, av, &ad); 1012 } 1013 1014 /* Check whether a task can use an open file descriptor to 1015 access an inode in a given way. Check access to the 1016 descriptor itself, and then use dentry_has_perm to 1017 check a particular permission to the file. 1018 Access to the descriptor is implicitly granted if it 1019 has the same SID as the process. If av is zero, then 1020 access to the file is not checked, e.g. for cases 1021 where only the descriptor is affected like seek. */ 1022 static int file_has_perm(struct task_struct *tsk, 1023 struct file *file, 1024 u32 av) 1025 { 1026 struct task_security_struct *tsec = tsk->security; 1027 struct file_security_struct *fsec = file->f_security; 1028 struct vfsmount *mnt = file->f_vfsmnt; 1029 struct dentry *dentry = file->f_dentry; 1030 struct inode *inode = dentry->d_inode; 1031 struct avc_audit_data ad; 1032 int rc; 1033 1034 AVC_AUDIT_DATA_INIT(&ad, FS); 1035 ad.u.fs.mnt = mnt; 1036 ad.u.fs.dentry = dentry; 1037 1038 if (tsec->sid != fsec->sid) { 1039 rc = avc_has_perm(tsec->sid, fsec->sid, 1040 SECCLASS_FD, 1041 FD__USE, 1042 &ad); 1043 if (rc) 1044 return rc; 1045 } 1046 1047 /* av is zero if only checking access to the descriptor. */ 1048 if (av) 1049 return inode_has_perm(tsk, inode, av, &ad); 1050 1051 return 0; 1052 } 1053 1054 /* Check whether a task can create a file. */ 1055 static int may_create(struct inode *dir, 1056 struct dentry *dentry, 1057 u16 tclass) 1058 { 1059 struct task_security_struct *tsec; 1060 struct inode_security_struct *dsec; 1061 struct superblock_security_struct *sbsec; 1062 u32 newsid; 1063 struct avc_audit_data ad; 1064 int rc; 1065 1066 tsec = current->security; 1067 dsec = dir->i_security; 1068 sbsec = dir->i_sb->s_security; 1069 1070 AVC_AUDIT_DATA_INIT(&ad, FS); 1071 ad.u.fs.dentry = dentry; 1072 1073 rc = avc_has_perm(tsec->sid, dsec->sid, SECCLASS_DIR, 1074 DIR__ADD_NAME | DIR__SEARCH, 1075 &ad); 1076 if (rc) 1077 return rc; 1078 1079 if (tsec->create_sid && sbsec->behavior != SECURITY_FS_USE_MNTPOINT) { 1080 newsid = tsec->create_sid; 1081 } else { 1082 rc = security_transition_sid(tsec->sid, dsec->sid, tclass, 1083 &newsid); 1084 if (rc) 1085 return rc; 1086 } 1087 1088 rc = avc_has_perm(tsec->sid, newsid, tclass, FILE__CREATE, &ad); 1089 if (rc) 1090 return rc; 1091 1092 return avc_has_perm(newsid, sbsec->sid, 1093 SECCLASS_FILESYSTEM, 1094 FILESYSTEM__ASSOCIATE, &ad); 1095 } 1096 1097 #define MAY_LINK 0 1098 #define MAY_UNLINK 1 1099 #define MAY_RMDIR 2 1100 1101 /* Check whether a task can link, unlink, or rmdir a file/directory. */ 1102 static int may_link(struct inode *dir, 1103 struct dentry *dentry, 1104 int kind) 1105 1106 { 1107 struct task_security_struct *tsec; 1108 struct inode_security_struct *dsec, *isec; 1109 struct avc_audit_data ad; 1110 u32 av; 1111 int rc; 1112 1113 tsec = current->security; 1114 dsec = dir->i_security; 1115 isec = dentry->d_inode->i_security; 1116 1117 AVC_AUDIT_DATA_INIT(&ad, FS); 1118 ad.u.fs.dentry = dentry; 1119 1120 av = DIR__SEARCH; 1121 av |= (kind ? DIR__REMOVE_NAME : DIR__ADD_NAME); 1122 rc = avc_has_perm(tsec->sid, dsec->sid, SECCLASS_DIR, av, &ad); 1123 if (rc) 1124 return rc; 1125 1126 switch (kind) { 1127 case MAY_LINK: 1128 av = FILE__LINK; 1129 break; 1130 case MAY_UNLINK: 1131 av = FILE__UNLINK; 1132 break; 1133 case MAY_RMDIR: 1134 av = DIR__RMDIR; 1135 break; 1136 default: 1137 printk(KERN_WARNING "may_link: unrecognized kind %d\n", kind); 1138 return 0; 1139 } 1140 1141 rc = avc_has_perm(tsec->sid, isec->sid, isec->sclass, av, &ad); 1142 return rc; 1143 } 1144 1145 static inline int may_rename(struct inode *old_dir, 1146 struct dentry *old_dentry, 1147 struct inode *new_dir, 1148 struct dentry *new_dentry) 1149 { 1150 struct task_security_struct *tsec; 1151 struct inode_security_struct *old_dsec, *new_dsec, *old_isec, *new_isec; 1152 struct avc_audit_data ad; 1153 u32 av; 1154 int old_is_dir, new_is_dir; 1155 int rc; 1156 1157 tsec = current->security; 1158 old_dsec = old_dir->i_security; 1159 old_isec = old_dentry->d_inode->i_security; 1160 old_is_dir = S_ISDIR(old_dentry->d_inode->i_mode); 1161 new_dsec = new_dir->i_security; 1162 1163 AVC_AUDIT_DATA_INIT(&ad, FS); 1164 1165 ad.u.fs.dentry = old_dentry; 1166 rc = avc_has_perm(tsec->sid, old_dsec->sid, SECCLASS_DIR, 1167 DIR__REMOVE_NAME | DIR__SEARCH, &ad); 1168 if (rc) 1169 return rc; 1170 rc = avc_has_perm(tsec->sid, old_isec->sid, 1171 old_isec->sclass, FILE__RENAME, &ad); 1172 if (rc) 1173 return rc; 1174 if (old_is_dir && new_dir != old_dir) { 1175 rc = avc_has_perm(tsec->sid, old_isec->sid, 1176 old_isec->sclass, DIR__REPARENT, &ad); 1177 if (rc) 1178 return rc; 1179 } 1180 1181 ad.u.fs.dentry = new_dentry; 1182 av = DIR__ADD_NAME | DIR__SEARCH; 1183 if (new_dentry->d_inode) 1184 av |= DIR__REMOVE_NAME; 1185 rc = avc_has_perm(tsec->sid, new_dsec->sid, SECCLASS_DIR, av, &ad); 1186 if (rc) 1187 return rc; 1188 if (new_dentry->d_inode) { 1189 new_isec = new_dentry->d_inode->i_security; 1190 new_is_dir = S_ISDIR(new_dentry->d_inode->i_mode); 1191 rc = avc_has_perm(tsec->sid, new_isec->sid, 1192 new_isec->sclass, 1193 (new_is_dir ? DIR__RMDIR : FILE__UNLINK), &ad); 1194 if (rc) 1195 return rc; 1196 } 1197 1198 return 0; 1199 } 1200 1201 /* Check whether a task can perform a filesystem operation. */ 1202 static int superblock_has_perm(struct task_struct *tsk, 1203 struct super_block *sb, 1204 u32 perms, 1205 struct avc_audit_data *ad) 1206 { 1207 struct task_security_struct *tsec; 1208 struct superblock_security_struct *sbsec; 1209 1210 tsec = tsk->security; 1211 sbsec = sb->s_security; 1212 return avc_has_perm(tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM, 1213 perms, ad); 1214 } 1215 1216 /* Convert a Linux mode and permission mask to an access vector. */ 1217 static inline u32 file_mask_to_av(int mode, int mask) 1218 { 1219 u32 av = 0; 1220 1221 if ((mode & S_IFMT) != S_IFDIR) { 1222 if (mask & MAY_EXEC) 1223 av |= FILE__EXECUTE; 1224 if (mask & MAY_READ) 1225 av |= FILE__READ; 1226 1227 if (mask & MAY_APPEND) 1228 av |= FILE__APPEND; 1229 else if (mask & MAY_WRITE) 1230 av |= FILE__WRITE; 1231 1232 } else { 1233 if (mask & MAY_EXEC) 1234 av |= DIR__SEARCH; 1235 if (mask & MAY_WRITE) 1236 av |= DIR__WRITE; 1237 if (mask & MAY_READ) 1238 av |= DIR__READ; 1239 } 1240 1241 return av; 1242 } 1243 1244 /* Convert a Linux file to an access vector. */ 1245 static inline u32 file_to_av(struct file *file) 1246 { 1247 u32 av = 0; 1248 1249 if (file->f_mode & FMODE_READ) 1250 av |= FILE__READ; 1251 if (file->f_mode & FMODE_WRITE) { 1252 if (file->f_flags & O_APPEND) 1253 av |= FILE__APPEND; 1254 else 1255 av |= FILE__WRITE; 1256 } 1257 1258 return av; 1259 } 1260 1261 /* Set an inode's SID to a specified value. */ 1262 static int inode_security_set_sid(struct inode *inode, u32 sid) 1263 { 1264 struct inode_security_struct *isec = inode->i_security; 1265 struct superblock_security_struct *sbsec = inode->i_sb->s_security; 1266 1267 if (!sbsec->initialized) { 1268 /* Defer initialization to selinux_complete_init. */ 1269 return 0; 1270 } 1271 1272 down(&isec->sem); 1273 isec->sclass = inode_mode_to_security_class(inode->i_mode); 1274 isec->sid = sid; 1275 isec->initialized = 1; 1276 up(&isec->sem); 1277 return 0; 1278 } 1279 1280 /* Hook functions begin here. */ 1281 1282 static int selinux_ptrace(struct task_struct *parent, struct task_struct *child) 1283 { 1284 struct task_security_struct *psec = parent->security; 1285 struct task_security_struct *csec = child->security; 1286 int rc; 1287 1288 rc = secondary_ops->ptrace(parent,child); 1289 if (rc) 1290 return rc; 1291 1292 rc = task_has_perm(parent, child, PROCESS__PTRACE); 1293 /* Save the SID of the tracing process for later use in apply_creds. */ 1294 if (!(child->ptrace & PT_PTRACED) && !rc) 1295 csec->ptrace_sid = psec->sid; 1296 return rc; 1297 } 1298 1299 static int selinux_capget(struct task_struct *target, kernel_cap_t *effective, 1300 kernel_cap_t *inheritable, kernel_cap_t *permitted) 1301 { 1302 int error; 1303 1304 error = task_has_perm(current, target, PROCESS__GETCAP); 1305 if (error) 1306 return error; 1307 1308 return secondary_ops->capget(target, effective, inheritable, permitted); 1309 } 1310 1311 static int selinux_capset_check(struct task_struct *target, kernel_cap_t *effective, 1312 kernel_cap_t *inheritable, kernel_cap_t *permitted) 1313 { 1314 int error; 1315 1316 error = secondary_ops->capset_check(target, effective, inheritable, permitted); 1317 if (error) 1318 return error; 1319 1320 return task_has_perm(current, target, PROCESS__SETCAP); 1321 } 1322 1323 static void selinux_capset_set(struct task_struct *target, kernel_cap_t *effective, 1324 kernel_cap_t *inheritable, kernel_cap_t *permitted) 1325 { 1326 secondary_ops->capset_set(target, effective, inheritable, permitted); 1327 } 1328 1329 static int selinux_capable(struct task_struct *tsk, int cap) 1330 { 1331 int rc; 1332 1333 rc = secondary_ops->capable(tsk, cap); 1334 if (rc) 1335 return rc; 1336 1337 return task_has_capability(tsk,cap); 1338 } 1339 1340 static int selinux_sysctl(ctl_table *table, int op) 1341 { 1342 int error = 0; 1343 u32 av; 1344 struct task_security_struct *tsec; 1345 u32 tsid; 1346 int rc; 1347 1348 rc = secondary_ops->sysctl(table, op); 1349 if (rc) 1350 return rc; 1351 1352 tsec = current->security; 1353 1354 rc = selinux_proc_get_sid(table->de, (op == 001) ? 1355 SECCLASS_DIR : SECCLASS_FILE, &tsid); 1356 if (rc) { 1357 /* Default to the well-defined sysctl SID. */ 1358 tsid = SECINITSID_SYSCTL; 1359 } 1360 1361 /* The op values are "defined" in sysctl.c, thereby creating 1362 * a bad coupling between this module and sysctl.c */ 1363 if(op == 001) { 1364 error = avc_has_perm(tsec->sid, tsid, 1365 SECCLASS_DIR, DIR__SEARCH, NULL); 1366 } else { 1367 av = 0; 1368 if (op & 004) 1369 av |= FILE__READ; 1370 if (op & 002) 1371 av |= FILE__WRITE; 1372 if (av) 1373 error = avc_has_perm(tsec->sid, tsid, 1374 SECCLASS_FILE, av, NULL); 1375 } 1376 1377 return error; 1378 } 1379 1380 static int selinux_quotactl(int cmds, int type, int id, struct super_block *sb) 1381 { 1382 int rc = 0; 1383 1384 if (!sb) 1385 return 0; 1386 1387 switch (cmds) { 1388 case Q_SYNC: 1389 case Q_QUOTAON: 1390 case Q_QUOTAOFF: 1391 case Q_SETINFO: 1392 case Q_SETQUOTA: 1393 rc = superblock_has_perm(current, 1394 sb, 1395 FILESYSTEM__QUOTAMOD, NULL); 1396 break; 1397 case Q_GETFMT: 1398 case Q_GETINFO: 1399 case Q_GETQUOTA: 1400 rc = superblock_has_perm(current, 1401 sb, 1402 FILESYSTEM__QUOTAGET, NULL); 1403 break; 1404 default: 1405 rc = 0; /* let the kernel handle invalid cmds */ 1406 break; 1407 } 1408 return rc; 1409 } 1410 1411 static int selinux_quota_on(struct dentry *dentry) 1412 { 1413 return dentry_has_perm(current, NULL, dentry, FILE__QUOTAON); 1414 } 1415 1416 static int selinux_syslog(int type) 1417 { 1418 int rc; 1419 1420 rc = secondary_ops->syslog(type); 1421 if (rc) 1422 return rc; 1423 1424 switch (type) { 1425 case 3: /* Read last kernel messages */ 1426 case 10: /* Return size of the log buffer */ 1427 rc = task_has_system(current, SYSTEM__SYSLOG_READ); 1428 break; 1429 case 6: /* Disable logging to console */ 1430 case 7: /* Enable logging to console */ 1431 case 8: /* Set level of messages printed to console */ 1432 rc = task_has_system(current, SYSTEM__SYSLOG_CONSOLE); 1433 break; 1434 case 0: /* Close log */ 1435 case 1: /* Open log */ 1436 case 2: /* Read from log */ 1437 case 4: /* Read/clear last kernel messages */ 1438 case 5: /* Clear ring buffer */ 1439 default: 1440 rc = task_has_system(current, SYSTEM__SYSLOG_MOD); 1441 break; 1442 } 1443 return rc; 1444 } 1445 1446 /* 1447 * Check that a process has enough memory to allocate a new virtual 1448 * mapping. 0 means there is enough memory for the allocation to 1449 * succeed and -ENOMEM implies there is not. 1450 * 1451 * Note that secondary_ops->capable and task_has_perm_noaudit return 0 1452 * if the capability is granted, but __vm_enough_memory requires 1 if 1453 * the capability is granted. 1454 * 1455 * Do not audit the selinux permission check, as this is applied to all 1456 * processes that allocate mappings. 1457 */ 1458 static int selinux_vm_enough_memory(long pages) 1459 { 1460 int rc, cap_sys_admin = 0; 1461 struct task_security_struct *tsec = current->security; 1462 1463 rc = secondary_ops->capable(current, CAP_SYS_ADMIN); 1464 if (rc == 0) 1465 rc = avc_has_perm_noaudit(tsec->sid, tsec->sid, 1466 SECCLASS_CAPABILITY, 1467 CAP_TO_MASK(CAP_SYS_ADMIN), 1468 NULL); 1469 1470 if (rc == 0) 1471 cap_sys_admin = 1; 1472 1473 return __vm_enough_memory(pages, cap_sys_admin); 1474 } 1475 1476 /* binprm security operations */ 1477 1478 static int selinux_bprm_alloc_security(struct linux_binprm *bprm) 1479 { 1480 struct bprm_security_struct *bsec; 1481 1482 bsec = kzalloc(sizeof(struct bprm_security_struct), GFP_KERNEL); 1483 if (!bsec) 1484 return -ENOMEM; 1485 1486 bsec->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 get_file(devnull); 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 u32 newsid, clen; 1962 int rc; 1963 char *namep = NULL, *context; 1964 1965 tsec = current->security; 1966 dsec = dir->i_security; 1967 sbsec = dir->i_sb->s_security; 1968 1969 if (tsec->create_sid && sbsec->behavior != SECURITY_FS_USE_MNTPOINT) { 1970 newsid = tsec->create_sid; 1971 } else { 1972 rc = security_transition_sid(tsec->sid, dsec->sid, 1973 inode_mode_to_security_class(inode->i_mode), 1974 &newsid); 1975 if (rc) { 1976 printk(KERN_WARNING "%s: " 1977 "security_transition_sid failed, rc=%d (dev=%s " 1978 "ino=%ld)\n", 1979 __FUNCTION__, 1980 -rc, inode->i_sb->s_id, inode->i_ino); 1981 return rc; 1982 } 1983 } 1984 1985 inode_security_set_sid(inode, newsid); 1986 1987 if (!ss_initialized || sbsec->behavior == SECURITY_FS_USE_MNTPOINT) 1988 return -EOPNOTSUPP; 1989 1990 if (name) { 1991 namep = kstrdup(XATTR_SELINUX_SUFFIX, GFP_KERNEL); 1992 if (!namep) 1993 return -ENOMEM; 1994 *name = namep; 1995 } 1996 1997 if (value && len) { 1998 rc = security_sid_to_context(newsid, &context, &clen); 1999 if (rc) { 2000 kfree(namep); 2001 return rc; 2002 } 2003 *value = context; 2004 *len = clen; 2005 } 2006 2007 return 0; 2008 } 2009 2010 static int selinux_inode_create(struct inode *dir, struct dentry *dentry, int mask) 2011 { 2012 return may_create(dir, dentry, SECCLASS_FILE); 2013 } 2014 2015 static int selinux_inode_link(struct dentry *old_dentry, struct inode *dir, struct dentry *new_dentry) 2016 { 2017 int rc; 2018 2019 rc = secondary_ops->inode_link(old_dentry,dir,new_dentry); 2020 if (rc) 2021 return rc; 2022 return may_link(dir, old_dentry, MAY_LINK); 2023 } 2024 2025 static int selinux_inode_unlink(struct inode *dir, struct dentry *dentry) 2026 { 2027 int rc; 2028 2029 rc = secondary_ops->inode_unlink(dir, dentry); 2030 if (rc) 2031 return rc; 2032 return may_link(dir, dentry, MAY_UNLINK); 2033 } 2034 2035 static int selinux_inode_symlink(struct inode *dir, struct dentry *dentry, const char *name) 2036 { 2037 return may_create(dir, dentry, SECCLASS_LNK_FILE); 2038 } 2039 2040 static int selinux_inode_mkdir(struct inode *dir, struct dentry *dentry, int mask) 2041 { 2042 return may_create(dir, dentry, SECCLASS_DIR); 2043 } 2044 2045 static int selinux_inode_rmdir(struct inode *dir, struct dentry *dentry) 2046 { 2047 return may_link(dir, dentry, MAY_RMDIR); 2048 } 2049 2050 static int selinux_inode_mknod(struct inode *dir, struct dentry *dentry, int mode, dev_t dev) 2051 { 2052 int rc; 2053 2054 rc = secondary_ops->inode_mknod(dir, dentry, mode, dev); 2055 if (rc) 2056 return rc; 2057 2058 return may_create(dir, dentry, inode_mode_to_security_class(mode)); 2059 } 2060 2061 static int selinux_inode_rename(struct inode *old_inode, struct dentry *old_dentry, 2062 struct inode *new_inode, struct dentry *new_dentry) 2063 { 2064 return may_rename(old_inode, old_dentry, new_inode, new_dentry); 2065 } 2066 2067 static int selinux_inode_readlink(struct dentry *dentry) 2068 { 2069 return dentry_has_perm(current, NULL, dentry, FILE__READ); 2070 } 2071 2072 static int selinux_inode_follow_link(struct dentry *dentry, struct nameidata *nameidata) 2073 { 2074 int rc; 2075 2076 rc = secondary_ops->inode_follow_link(dentry,nameidata); 2077 if (rc) 2078 return rc; 2079 return dentry_has_perm(current, NULL, dentry, FILE__READ); 2080 } 2081 2082 static int selinux_inode_permission(struct inode *inode, int mask, 2083 struct nameidata *nd) 2084 { 2085 int rc; 2086 2087 rc = secondary_ops->inode_permission(inode, mask, nd); 2088 if (rc) 2089 return rc; 2090 2091 if (!mask) { 2092 /* No permission to check. Existence test. */ 2093 return 0; 2094 } 2095 2096 return inode_has_perm(current, inode, 2097 file_mask_to_av(inode->i_mode, mask), NULL); 2098 } 2099 2100 static int selinux_inode_setattr(struct dentry *dentry, struct iattr *iattr) 2101 { 2102 int rc; 2103 2104 rc = secondary_ops->inode_setattr(dentry, iattr); 2105 if (rc) 2106 return rc; 2107 2108 if (iattr->ia_valid & ATTR_FORCE) 2109 return 0; 2110 2111 if (iattr->ia_valid & (ATTR_MODE | ATTR_UID | ATTR_GID | 2112 ATTR_ATIME_SET | ATTR_MTIME_SET)) 2113 return dentry_has_perm(current, NULL, dentry, FILE__SETATTR); 2114 2115 return dentry_has_perm(current, NULL, dentry, FILE__WRITE); 2116 } 2117 2118 static int selinux_inode_getattr(struct vfsmount *mnt, struct dentry *dentry) 2119 { 2120 return dentry_has_perm(current, mnt, dentry, FILE__GETATTR); 2121 } 2122 2123 static int selinux_inode_setxattr(struct dentry *dentry, char *name, void *value, size_t size, int flags) 2124 { 2125 struct task_security_struct *tsec = current->security; 2126 struct inode *inode = dentry->d_inode; 2127 struct inode_security_struct *isec = inode->i_security; 2128 struct superblock_security_struct *sbsec; 2129 struct avc_audit_data ad; 2130 u32 newsid; 2131 int rc = 0; 2132 2133 if (strcmp(name, XATTR_NAME_SELINUX)) { 2134 if (!strncmp(name, XATTR_SECURITY_PREFIX, 2135 sizeof XATTR_SECURITY_PREFIX - 1) && 2136 !capable(CAP_SYS_ADMIN)) { 2137 /* A different attribute in the security namespace. 2138 Restrict to administrator. */ 2139 return -EPERM; 2140 } 2141 2142 /* Not an attribute we recognize, so just check the 2143 ordinary setattr permission. */ 2144 return dentry_has_perm(current, NULL, dentry, FILE__SETATTR); 2145 } 2146 2147 sbsec = inode->i_sb->s_security; 2148 if (sbsec->behavior == SECURITY_FS_USE_MNTPOINT) 2149 return -EOPNOTSUPP; 2150 2151 if ((current->fsuid != inode->i_uid) && !capable(CAP_FOWNER)) 2152 return -EPERM; 2153 2154 AVC_AUDIT_DATA_INIT(&ad,FS); 2155 ad.u.fs.dentry = dentry; 2156 2157 rc = avc_has_perm(tsec->sid, isec->sid, isec->sclass, 2158 FILE__RELABELFROM, &ad); 2159 if (rc) 2160 return rc; 2161 2162 rc = security_context_to_sid(value, size, &newsid); 2163 if (rc) 2164 return rc; 2165 2166 rc = avc_has_perm(tsec->sid, newsid, isec->sclass, 2167 FILE__RELABELTO, &ad); 2168 if (rc) 2169 return rc; 2170 2171 rc = security_validate_transition(isec->sid, newsid, tsec->sid, 2172 isec->sclass); 2173 if (rc) 2174 return rc; 2175 2176 return avc_has_perm(newsid, 2177 sbsec->sid, 2178 SECCLASS_FILESYSTEM, 2179 FILESYSTEM__ASSOCIATE, 2180 &ad); 2181 } 2182 2183 static void selinux_inode_post_setxattr(struct dentry *dentry, char *name, 2184 void *value, size_t size, int flags) 2185 { 2186 struct inode *inode = dentry->d_inode; 2187 struct inode_security_struct *isec = inode->i_security; 2188 u32 newsid; 2189 int rc; 2190 2191 if (strcmp(name, XATTR_NAME_SELINUX)) { 2192 /* Not an attribute we recognize, so nothing to do. */ 2193 return; 2194 } 2195 2196 rc = security_context_to_sid(value, size, &newsid); 2197 if (rc) { 2198 printk(KERN_WARNING "%s: unable to obtain SID for context " 2199 "%s, rc=%d\n", __FUNCTION__, (char*)value, -rc); 2200 return; 2201 } 2202 2203 isec->sid = newsid; 2204 return; 2205 } 2206 2207 static int selinux_inode_getxattr (struct dentry *dentry, char *name) 2208 { 2209 return dentry_has_perm(current, NULL, dentry, FILE__GETATTR); 2210 } 2211 2212 static int selinux_inode_listxattr (struct dentry *dentry) 2213 { 2214 return dentry_has_perm(current, NULL, dentry, FILE__GETATTR); 2215 } 2216 2217 static int selinux_inode_removexattr (struct dentry *dentry, char *name) 2218 { 2219 if (strcmp(name, XATTR_NAME_SELINUX)) { 2220 if (!strncmp(name, XATTR_SECURITY_PREFIX, 2221 sizeof XATTR_SECURITY_PREFIX - 1) && 2222 !capable(CAP_SYS_ADMIN)) { 2223 /* A different attribute in the security namespace. 2224 Restrict to administrator. */ 2225 return -EPERM; 2226 } 2227 2228 /* Not an attribute we recognize, so just check the 2229 ordinary setattr permission. Might want a separate 2230 permission for removexattr. */ 2231 return dentry_has_perm(current, NULL, dentry, FILE__SETATTR); 2232 } 2233 2234 /* No one is allowed to remove a SELinux security label. 2235 You can change the label, but all data must be labeled. */ 2236 return -EACCES; 2237 } 2238 2239 static const char *selinux_inode_xattr_getsuffix(void) 2240 { 2241 return XATTR_SELINUX_SUFFIX; 2242 } 2243 2244 /* 2245 * Copy the in-core inode security context value to the user. If the 2246 * getxattr() prior to this succeeded, check to see if we need to 2247 * canonicalize the value to be finally returned to the user. 2248 * 2249 * Permission check is handled by selinux_inode_getxattr hook. 2250 */ 2251 static int selinux_inode_getsecurity(const struct inode *inode, const char *name, void *buffer, size_t size, int err) 2252 { 2253 struct inode_security_struct *isec = inode->i_security; 2254 2255 if (strcmp(name, XATTR_SELINUX_SUFFIX)) 2256 return -EOPNOTSUPP; 2257 2258 return selinux_getsecurity(isec->sid, buffer, size); 2259 } 2260 2261 static int selinux_inode_setsecurity(struct inode *inode, const char *name, 2262 const void *value, size_t size, int flags) 2263 { 2264 struct inode_security_struct *isec = inode->i_security; 2265 u32 newsid; 2266 int rc; 2267 2268 if (strcmp(name, XATTR_SELINUX_SUFFIX)) 2269 return -EOPNOTSUPP; 2270 2271 if (!value || !size) 2272 return -EACCES; 2273 2274 rc = security_context_to_sid((void*)value, size, &newsid); 2275 if (rc) 2276 return rc; 2277 2278 isec->sid = newsid; 2279 return 0; 2280 } 2281 2282 static int selinux_inode_listsecurity(struct inode *inode, char *buffer, size_t buffer_size) 2283 { 2284 const int len = sizeof(XATTR_NAME_SELINUX); 2285 if (buffer && len <= buffer_size) 2286 memcpy(buffer, XATTR_NAME_SELINUX, len); 2287 return len; 2288 } 2289 2290 /* file security operations */ 2291 2292 static int selinux_file_permission(struct file *file, int mask) 2293 { 2294 struct inode *inode = file->f_dentry->d_inode; 2295 2296 if (!mask) { 2297 /* No permission to check. Existence test. */ 2298 return 0; 2299 } 2300 2301 /* file_mask_to_av won't add FILE__WRITE if MAY_APPEND is set */ 2302 if ((file->f_flags & O_APPEND) && (mask & MAY_WRITE)) 2303 mask |= MAY_APPEND; 2304 2305 return file_has_perm(current, file, 2306 file_mask_to_av(inode->i_mode, mask)); 2307 } 2308 2309 static int selinux_file_alloc_security(struct file *file) 2310 { 2311 return file_alloc_security(file); 2312 } 2313 2314 static void selinux_file_free_security(struct file *file) 2315 { 2316 file_free_security(file); 2317 } 2318 2319 static int selinux_file_ioctl(struct file *file, unsigned int cmd, 2320 unsigned long arg) 2321 { 2322 int error = 0; 2323 2324 switch (cmd) { 2325 case FIONREAD: 2326 /* fall through */ 2327 case FIBMAP: 2328 /* fall through */ 2329 case FIGETBSZ: 2330 /* fall through */ 2331 case EXT2_IOC_GETFLAGS: 2332 /* fall through */ 2333 case EXT2_IOC_GETVERSION: 2334 error = file_has_perm(current, file, FILE__GETATTR); 2335 break; 2336 2337 case EXT2_IOC_SETFLAGS: 2338 /* fall through */ 2339 case EXT2_IOC_SETVERSION: 2340 error = file_has_perm(current, file, FILE__SETATTR); 2341 break; 2342 2343 /* sys_ioctl() checks */ 2344 case FIONBIO: 2345 /* fall through */ 2346 case FIOASYNC: 2347 error = file_has_perm(current, file, 0); 2348 break; 2349 2350 case KDSKBENT: 2351 case KDSKBSENT: 2352 error = task_has_capability(current,CAP_SYS_TTY_CONFIG); 2353 break; 2354 2355 /* default case assumes that the command will go 2356 * to the file's ioctl() function. 2357 */ 2358 default: 2359 error = file_has_perm(current, file, FILE__IOCTL); 2360 2361 } 2362 return error; 2363 } 2364 2365 static int file_map_prot_check(struct file *file, unsigned long prot, int shared) 2366 { 2367 #ifndef CONFIG_PPC32 2368 if ((prot & PROT_EXEC) && (!file || (!shared && (prot & PROT_WRITE)))) { 2369 /* 2370 * We are making executable an anonymous mapping or a 2371 * private file mapping that will also be writable. 2372 * This has an additional check. 2373 */ 2374 int rc = task_has_perm(current, current, PROCESS__EXECMEM); 2375 if (rc) 2376 return rc; 2377 } 2378 #endif 2379 2380 if (file) { 2381 /* read access is always possible with a mapping */ 2382 u32 av = FILE__READ; 2383 2384 /* write access only matters if the mapping is shared */ 2385 if (shared && (prot & PROT_WRITE)) 2386 av |= FILE__WRITE; 2387 2388 if (prot & PROT_EXEC) 2389 av |= FILE__EXECUTE; 2390 2391 return file_has_perm(current, file, av); 2392 } 2393 return 0; 2394 } 2395 2396 static int selinux_file_mmap(struct file *file, unsigned long reqprot, 2397 unsigned long prot, unsigned long flags) 2398 { 2399 int rc; 2400 2401 rc = secondary_ops->file_mmap(file, reqprot, prot, flags); 2402 if (rc) 2403 return rc; 2404 2405 if (selinux_checkreqprot) 2406 prot = reqprot; 2407 2408 return file_map_prot_check(file, prot, 2409 (flags & MAP_TYPE) == MAP_SHARED); 2410 } 2411 2412 static int selinux_file_mprotect(struct vm_area_struct *vma, 2413 unsigned long reqprot, 2414 unsigned long prot) 2415 { 2416 int rc; 2417 2418 rc = secondary_ops->file_mprotect(vma, reqprot, prot); 2419 if (rc) 2420 return rc; 2421 2422 if (selinux_checkreqprot) 2423 prot = reqprot; 2424 2425 #ifndef CONFIG_PPC32 2426 if ((prot & PROT_EXEC) && !(vma->vm_flags & VM_EXEC)) { 2427 rc = 0; 2428 if (vma->vm_start >= vma->vm_mm->start_brk && 2429 vma->vm_end <= vma->vm_mm->brk) { 2430 rc = task_has_perm(current, current, 2431 PROCESS__EXECHEAP); 2432 } else if (!vma->vm_file && 2433 vma->vm_start <= vma->vm_mm->start_stack && 2434 vma->vm_end >= vma->vm_mm->start_stack) { 2435 rc = task_has_perm(current, current, PROCESS__EXECSTACK); 2436 } else if (vma->vm_file && vma->anon_vma) { 2437 /* 2438 * We are making executable a file mapping that has 2439 * had some COW done. Since pages might have been 2440 * written, check ability to execute the possibly 2441 * modified content. This typically should only 2442 * occur for text relocations. 2443 */ 2444 rc = file_has_perm(current, vma->vm_file, 2445 FILE__EXECMOD); 2446 } 2447 if (rc) 2448 return rc; 2449 } 2450 #endif 2451 2452 return file_map_prot_check(vma->vm_file, prot, vma->vm_flags&VM_SHARED); 2453 } 2454 2455 static int selinux_file_lock(struct file *file, unsigned int cmd) 2456 { 2457 return file_has_perm(current, file, FILE__LOCK); 2458 } 2459 2460 static int selinux_file_fcntl(struct file *file, unsigned int cmd, 2461 unsigned long arg) 2462 { 2463 int err = 0; 2464 2465 switch (cmd) { 2466 case F_SETFL: 2467 if (!file->f_dentry || !file->f_dentry->d_inode) { 2468 err = -EINVAL; 2469 break; 2470 } 2471 2472 if ((file->f_flags & O_APPEND) && !(arg & O_APPEND)) { 2473 err = file_has_perm(current, file,FILE__WRITE); 2474 break; 2475 } 2476 /* fall through */ 2477 case F_SETOWN: 2478 case F_SETSIG: 2479 case F_GETFL: 2480 case F_GETOWN: 2481 case F_GETSIG: 2482 /* Just check FD__USE permission */ 2483 err = file_has_perm(current, file, 0); 2484 break; 2485 case F_GETLK: 2486 case F_SETLK: 2487 case F_SETLKW: 2488 #if BITS_PER_LONG == 32 2489 case F_GETLK64: 2490 case F_SETLK64: 2491 case F_SETLKW64: 2492 #endif 2493 if (!file->f_dentry || !file->f_dentry->d_inode) { 2494 err = -EINVAL; 2495 break; 2496 } 2497 err = file_has_perm(current, file, FILE__LOCK); 2498 break; 2499 } 2500 2501 return err; 2502 } 2503 2504 static int selinux_file_set_fowner(struct file *file) 2505 { 2506 struct task_security_struct *tsec; 2507 struct file_security_struct *fsec; 2508 2509 tsec = current->security; 2510 fsec = file->f_security; 2511 fsec->fown_sid = tsec->sid; 2512 2513 return 0; 2514 } 2515 2516 static int selinux_file_send_sigiotask(struct task_struct *tsk, 2517 struct fown_struct *fown, int signum) 2518 { 2519 struct file *file; 2520 u32 perm; 2521 struct task_security_struct *tsec; 2522 struct file_security_struct *fsec; 2523 2524 /* struct fown_struct is never outside the context of a struct file */ 2525 file = (struct file *)((long)fown - offsetof(struct file,f_owner)); 2526 2527 tsec = tsk->security; 2528 fsec = file->f_security; 2529 2530 if (!signum) 2531 perm = signal_to_av(SIGIO); /* as per send_sigio_to_task */ 2532 else 2533 perm = signal_to_av(signum); 2534 2535 return avc_has_perm(fsec->fown_sid, tsec->sid, 2536 SECCLASS_PROCESS, perm, NULL); 2537 } 2538 2539 static int selinux_file_receive(struct file *file) 2540 { 2541 return file_has_perm(current, file, file_to_av(file)); 2542 } 2543 2544 /* task security operations */ 2545 2546 static int selinux_task_create(unsigned long clone_flags) 2547 { 2548 int rc; 2549 2550 rc = secondary_ops->task_create(clone_flags); 2551 if (rc) 2552 return rc; 2553 2554 return task_has_perm(current, current, PROCESS__FORK); 2555 } 2556 2557 static int selinux_task_alloc_security(struct task_struct *tsk) 2558 { 2559 struct task_security_struct *tsec1, *tsec2; 2560 int rc; 2561 2562 tsec1 = current->security; 2563 2564 rc = task_alloc_security(tsk); 2565 if (rc) 2566 return rc; 2567 tsec2 = tsk->security; 2568 2569 tsec2->osid = tsec1->osid; 2570 tsec2->sid = tsec1->sid; 2571 2572 /* Retain the exec and create SIDs across fork */ 2573 tsec2->exec_sid = tsec1->exec_sid; 2574 tsec2->create_sid = tsec1->create_sid; 2575 2576 /* Retain ptracer SID across fork, if any. 2577 This will be reset by the ptrace hook upon any 2578 subsequent ptrace_attach operations. */ 2579 tsec2->ptrace_sid = tsec1->ptrace_sid; 2580 2581 return 0; 2582 } 2583 2584 static void selinux_task_free_security(struct task_struct *tsk) 2585 { 2586 task_free_security(tsk); 2587 } 2588 2589 static int selinux_task_setuid(uid_t id0, uid_t id1, uid_t id2, int flags) 2590 { 2591 /* Since setuid only affects the current process, and 2592 since the SELinux controls are not based on the Linux 2593 identity attributes, SELinux does not need to control 2594 this operation. However, SELinux does control the use 2595 of the CAP_SETUID and CAP_SETGID capabilities using the 2596 capable hook. */ 2597 return 0; 2598 } 2599 2600 static int selinux_task_post_setuid(uid_t id0, uid_t id1, uid_t id2, int flags) 2601 { 2602 return secondary_ops->task_post_setuid(id0,id1,id2,flags); 2603 } 2604 2605 static int selinux_task_setgid(gid_t id0, gid_t id1, gid_t id2, int flags) 2606 { 2607 /* See the comment for setuid above. */ 2608 return 0; 2609 } 2610 2611 static int selinux_task_setpgid(struct task_struct *p, pid_t pgid) 2612 { 2613 return task_has_perm(current, p, PROCESS__SETPGID); 2614 } 2615 2616 static int selinux_task_getpgid(struct task_struct *p) 2617 { 2618 return task_has_perm(current, p, PROCESS__GETPGID); 2619 } 2620 2621 static int selinux_task_getsid(struct task_struct *p) 2622 { 2623 return task_has_perm(current, p, PROCESS__GETSESSION); 2624 } 2625 2626 static int selinux_task_setgroups(struct group_info *group_info) 2627 { 2628 /* See the comment for setuid above. */ 2629 return 0; 2630 } 2631 2632 static int selinux_task_setnice(struct task_struct *p, int nice) 2633 { 2634 int rc; 2635 2636 rc = secondary_ops->task_setnice(p, nice); 2637 if (rc) 2638 return rc; 2639 2640 return task_has_perm(current,p, PROCESS__SETSCHED); 2641 } 2642 2643 static int selinux_task_setrlimit(unsigned int resource, struct rlimit *new_rlim) 2644 { 2645 struct rlimit *old_rlim = current->signal->rlim + resource; 2646 int rc; 2647 2648 rc = secondary_ops->task_setrlimit(resource, new_rlim); 2649 if (rc) 2650 return rc; 2651 2652 /* Control the ability to change the hard limit (whether 2653 lowering or raising it), so that the hard limit can 2654 later be used as a safe reset point for the soft limit 2655 upon context transitions. See selinux_bprm_apply_creds. */ 2656 if (old_rlim->rlim_max != new_rlim->rlim_max) 2657 return task_has_perm(current, current, PROCESS__SETRLIMIT); 2658 2659 return 0; 2660 } 2661 2662 static int selinux_task_setscheduler(struct task_struct *p, int policy, struct sched_param *lp) 2663 { 2664 return task_has_perm(current, p, PROCESS__SETSCHED); 2665 } 2666 2667 static int selinux_task_getscheduler(struct task_struct *p) 2668 { 2669 return task_has_perm(current, p, PROCESS__GETSCHED); 2670 } 2671 2672 static int selinux_task_kill(struct task_struct *p, struct siginfo *info, int sig) 2673 { 2674 u32 perm; 2675 int rc; 2676 2677 rc = secondary_ops->task_kill(p, info, sig); 2678 if (rc) 2679 return rc; 2680 2681 if (info != SEND_SIG_NOINFO && (is_si_special(info) || SI_FROMKERNEL(info))) 2682 return 0; 2683 2684 if (!sig) 2685 perm = PROCESS__SIGNULL; /* null signal; existence test */ 2686 else 2687 perm = signal_to_av(sig); 2688 2689 return task_has_perm(current, p, perm); 2690 } 2691 2692 static int selinux_task_prctl(int option, 2693 unsigned long arg2, 2694 unsigned long arg3, 2695 unsigned long arg4, 2696 unsigned long arg5) 2697 { 2698 /* The current prctl operations do not appear to require 2699 any SELinux controls since they merely observe or modify 2700 the state of the current process. */ 2701 return 0; 2702 } 2703 2704 static int selinux_task_wait(struct task_struct *p) 2705 { 2706 u32 perm; 2707 2708 perm = signal_to_av(p->exit_signal); 2709 2710 return task_has_perm(p, current, perm); 2711 } 2712 2713 static void selinux_task_reparent_to_init(struct task_struct *p) 2714 { 2715 struct task_security_struct *tsec; 2716 2717 secondary_ops->task_reparent_to_init(p); 2718 2719 tsec = p->security; 2720 tsec->osid = tsec->sid; 2721 tsec->sid = SECINITSID_KERNEL; 2722 return; 2723 } 2724 2725 static void selinux_task_to_inode(struct task_struct *p, 2726 struct inode *inode) 2727 { 2728 struct task_security_struct *tsec = p->security; 2729 struct inode_security_struct *isec = inode->i_security; 2730 2731 isec->sid = tsec->sid; 2732 isec->initialized = 1; 2733 return; 2734 } 2735 2736 /* Returns error only if unable to parse addresses */ 2737 static int selinux_parse_skb_ipv4(struct sk_buff *skb, struct avc_audit_data *ad) 2738 { 2739 int offset, ihlen, ret = -EINVAL; 2740 struct iphdr _iph, *ih; 2741 2742 offset = skb->nh.raw - skb->data; 2743 ih = skb_header_pointer(skb, offset, sizeof(_iph), &_iph); 2744 if (ih == NULL) 2745 goto out; 2746 2747 ihlen = ih->ihl * 4; 2748 if (ihlen < sizeof(_iph)) 2749 goto out; 2750 2751 ad->u.net.v4info.saddr = ih->saddr; 2752 ad->u.net.v4info.daddr = ih->daddr; 2753 ret = 0; 2754 2755 switch (ih->protocol) { 2756 case IPPROTO_TCP: { 2757 struct tcphdr _tcph, *th; 2758 2759 if (ntohs(ih->frag_off) & IP_OFFSET) 2760 break; 2761 2762 offset += ihlen; 2763 th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph); 2764 if (th == NULL) 2765 break; 2766 2767 ad->u.net.sport = th->source; 2768 ad->u.net.dport = th->dest; 2769 break; 2770 } 2771 2772 case IPPROTO_UDP: { 2773 struct udphdr _udph, *uh; 2774 2775 if (ntohs(ih->frag_off) & IP_OFFSET) 2776 break; 2777 2778 offset += ihlen; 2779 uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph); 2780 if (uh == NULL) 2781 break; 2782 2783 ad->u.net.sport = uh->source; 2784 ad->u.net.dport = uh->dest; 2785 break; 2786 } 2787 2788 default: 2789 break; 2790 } 2791 out: 2792 return ret; 2793 } 2794 2795 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE) 2796 2797 /* Returns error only if unable to parse addresses */ 2798 static int selinux_parse_skb_ipv6(struct sk_buff *skb, struct avc_audit_data *ad) 2799 { 2800 u8 nexthdr; 2801 int ret = -EINVAL, offset; 2802 struct ipv6hdr _ipv6h, *ip6; 2803 2804 offset = skb->nh.raw - skb->data; 2805 ip6 = skb_header_pointer(skb, offset, sizeof(_ipv6h), &_ipv6h); 2806 if (ip6 == NULL) 2807 goto out; 2808 2809 ipv6_addr_copy(&ad->u.net.v6info.saddr, &ip6->saddr); 2810 ipv6_addr_copy(&ad->u.net.v6info.daddr, &ip6->daddr); 2811 ret = 0; 2812 2813 nexthdr = ip6->nexthdr; 2814 offset += sizeof(_ipv6h); 2815 offset = ipv6_skip_exthdr(skb, offset, &nexthdr); 2816 if (offset < 0) 2817 goto out; 2818 2819 switch (nexthdr) { 2820 case IPPROTO_TCP: { 2821 struct tcphdr _tcph, *th; 2822 2823 th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph); 2824 if (th == NULL) 2825 break; 2826 2827 ad->u.net.sport = th->source; 2828 ad->u.net.dport = th->dest; 2829 break; 2830 } 2831 2832 case IPPROTO_UDP: { 2833 struct udphdr _udph, *uh; 2834 2835 uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph); 2836 if (uh == NULL) 2837 break; 2838 2839 ad->u.net.sport = uh->source; 2840 ad->u.net.dport = uh->dest; 2841 break; 2842 } 2843 2844 /* includes fragments */ 2845 default: 2846 break; 2847 } 2848 out: 2849 return ret; 2850 } 2851 2852 #endif /* IPV6 */ 2853 2854 static int selinux_parse_skb(struct sk_buff *skb, struct avc_audit_data *ad, 2855 char **addrp, int *len, int src) 2856 { 2857 int ret = 0; 2858 2859 switch (ad->u.net.family) { 2860 case PF_INET: 2861 ret = selinux_parse_skb_ipv4(skb, ad); 2862 if (ret || !addrp) 2863 break; 2864 *len = 4; 2865 *addrp = (char *)(src ? &ad->u.net.v4info.saddr : 2866 &ad->u.net.v4info.daddr); 2867 break; 2868 2869 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE) 2870 case PF_INET6: 2871 ret = selinux_parse_skb_ipv6(skb, ad); 2872 if (ret || !addrp) 2873 break; 2874 *len = 16; 2875 *addrp = (char *)(src ? &ad->u.net.v6info.saddr : 2876 &ad->u.net.v6info.daddr); 2877 break; 2878 #endif /* IPV6 */ 2879 default: 2880 break; 2881 } 2882 2883 return ret; 2884 } 2885 2886 /* socket security operations */ 2887 static int socket_has_perm(struct task_struct *task, struct socket *sock, 2888 u32 perms) 2889 { 2890 struct inode_security_struct *isec; 2891 struct task_security_struct *tsec; 2892 struct avc_audit_data ad; 2893 int err = 0; 2894 2895 tsec = task->security; 2896 isec = SOCK_INODE(sock)->i_security; 2897 2898 if (isec->sid == SECINITSID_KERNEL) 2899 goto out; 2900 2901 AVC_AUDIT_DATA_INIT(&ad,NET); 2902 ad.u.net.sk = sock->sk; 2903 err = avc_has_perm(tsec->sid, isec->sid, isec->sclass, perms, &ad); 2904 2905 out: 2906 return err; 2907 } 2908 2909 static int selinux_socket_create(int family, int type, 2910 int protocol, int kern) 2911 { 2912 int err = 0; 2913 struct task_security_struct *tsec; 2914 2915 if (kern) 2916 goto out; 2917 2918 tsec = current->security; 2919 err = avc_has_perm(tsec->sid, tsec->sid, 2920 socket_type_to_security_class(family, type, 2921 protocol), SOCKET__CREATE, NULL); 2922 2923 out: 2924 return err; 2925 } 2926 2927 static void selinux_socket_post_create(struct socket *sock, int family, 2928 int type, int protocol, int kern) 2929 { 2930 struct inode_security_struct *isec; 2931 struct task_security_struct *tsec; 2932 2933 isec = SOCK_INODE(sock)->i_security; 2934 2935 tsec = current->security; 2936 isec->sclass = socket_type_to_security_class(family, type, protocol); 2937 isec->sid = kern ? SECINITSID_KERNEL : tsec->sid; 2938 isec->initialized = 1; 2939 2940 return; 2941 } 2942 2943 /* Range of port numbers used to automatically bind. 2944 Need to determine whether we should perform a name_bind 2945 permission check between the socket and the port number. */ 2946 #define ip_local_port_range_0 sysctl_local_port_range[0] 2947 #define ip_local_port_range_1 sysctl_local_port_range[1] 2948 2949 static int selinux_socket_bind(struct socket *sock, struct sockaddr *address, int addrlen) 2950 { 2951 u16 family; 2952 int err; 2953 2954 err = socket_has_perm(current, sock, SOCKET__BIND); 2955 if (err) 2956 goto out; 2957 2958 /* 2959 * If PF_INET or PF_INET6, check name_bind permission for the port. 2960 * Multiple address binding for SCTP is not supported yet: we just 2961 * check the first address now. 2962 */ 2963 family = sock->sk->sk_family; 2964 if (family == PF_INET || family == PF_INET6) { 2965 char *addrp; 2966 struct inode_security_struct *isec; 2967 struct task_security_struct *tsec; 2968 struct avc_audit_data ad; 2969 struct sockaddr_in *addr4 = NULL; 2970 struct sockaddr_in6 *addr6 = NULL; 2971 unsigned short snum; 2972 struct sock *sk = sock->sk; 2973 u32 sid, node_perm, addrlen; 2974 2975 tsec = current->security; 2976 isec = SOCK_INODE(sock)->i_security; 2977 2978 if (family == PF_INET) { 2979 addr4 = (struct sockaddr_in *)address; 2980 snum = ntohs(addr4->sin_port); 2981 addrlen = sizeof(addr4->sin_addr.s_addr); 2982 addrp = (char *)&addr4->sin_addr.s_addr; 2983 } else { 2984 addr6 = (struct sockaddr_in6 *)address; 2985 snum = ntohs(addr6->sin6_port); 2986 addrlen = sizeof(addr6->sin6_addr.s6_addr); 2987 addrp = (char *)&addr6->sin6_addr.s6_addr; 2988 } 2989 2990 if (snum&&(snum < max(PROT_SOCK,ip_local_port_range_0) || 2991 snum > ip_local_port_range_1)) { 2992 err = security_port_sid(sk->sk_family, sk->sk_type, 2993 sk->sk_protocol, snum, &sid); 2994 if (err) 2995 goto out; 2996 AVC_AUDIT_DATA_INIT(&ad,NET); 2997 ad.u.net.sport = htons(snum); 2998 ad.u.net.family = family; 2999 err = avc_has_perm(isec->sid, sid, 3000 isec->sclass, 3001 SOCKET__NAME_BIND, &ad); 3002 if (err) 3003 goto out; 3004 } 3005 3006 switch(isec->sclass) { 3007 case SECCLASS_TCP_SOCKET: 3008 node_perm = TCP_SOCKET__NODE_BIND; 3009 break; 3010 3011 case SECCLASS_UDP_SOCKET: 3012 node_perm = UDP_SOCKET__NODE_BIND; 3013 break; 3014 3015 default: 3016 node_perm = RAWIP_SOCKET__NODE_BIND; 3017 break; 3018 } 3019 3020 err = security_node_sid(family, addrp, addrlen, &sid); 3021 if (err) 3022 goto out; 3023 3024 AVC_AUDIT_DATA_INIT(&ad,NET); 3025 ad.u.net.sport = htons(snum); 3026 ad.u.net.family = family; 3027 3028 if (family == PF_INET) 3029 ad.u.net.v4info.saddr = addr4->sin_addr.s_addr; 3030 else 3031 ipv6_addr_copy(&ad.u.net.v6info.saddr, &addr6->sin6_addr); 3032 3033 err = avc_has_perm(isec->sid, sid, 3034 isec->sclass, node_perm, &ad); 3035 if (err) 3036 goto out; 3037 } 3038 out: 3039 return err; 3040 } 3041 3042 static int selinux_socket_connect(struct socket *sock, struct sockaddr *address, int addrlen) 3043 { 3044 struct inode_security_struct *isec; 3045 int err; 3046 3047 err = socket_has_perm(current, sock, SOCKET__CONNECT); 3048 if (err) 3049 return err; 3050 3051 /* 3052 * If a TCP socket, check name_connect permission for the port. 3053 */ 3054 isec = SOCK_INODE(sock)->i_security; 3055 if (isec->sclass == SECCLASS_TCP_SOCKET) { 3056 struct sock *sk = sock->sk; 3057 struct avc_audit_data ad; 3058 struct sockaddr_in *addr4 = NULL; 3059 struct sockaddr_in6 *addr6 = NULL; 3060 unsigned short snum; 3061 u32 sid; 3062 3063 if (sk->sk_family == PF_INET) { 3064 addr4 = (struct sockaddr_in *)address; 3065 if (addrlen < sizeof(struct sockaddr_in)) 3066 return -EINVAL; 3067 snum = ntohs(addr4->sin_port); 3068 } else { 3069 addr6 = (struct sockaddr_in6 *)address; 3070 if (addrlen < SIN6_LEN_RFC2133) 3071 return -EINVAL; 3072 snum = ntohs(addr6->sin6_port); 3073 } 3074 3075 err = security_port_sid(sk->sk_family, sk->sk_type, 3076 sk->sk_protocol, snum, &sid); 3077 if (err) 3078 goto out; 3079 3080 AVC_AUDIT_DATA_INIT(&ad,NET); 3081 ad.u.net.dport = htons(snum); 3082 ad.u.net.family = sk->sk_family; 3083 err = avc_has_perm(isec->sid, sid, isec->sclass, 3084 TCP_SOCKET__NAME_CONNECT, &ad); 3085 if (err) 3086 goto out; 3087 } 3088 3089 out: 3090 return err; 3091 } 3092 3093 static int selinux_socket_listen(struct socket *sock, int backlog) 3094 { 3095 return socket_has_perm(current, sock, SOCKET__LISTEN); 3096 } 3097 3098 static int selinux_socket_accept(struct socket *sock, struct socket *newsock) 3099 { 3100 int err; 3101 struct inode_security_struct *isec; 3102 struct inode_security_struct *newisec; 3103 3104 err = socket_has_perm(current, sock, SOCKET__ACCEPT); 3105 if (err) 3106 return err; 3107 3108 newisec = SOCK_INODE(newsock)->i_security; 3109 3110 isec = SOCK_INODE(sock)->i_security; 3111 newisec->sclass = isec->sclass; 3112 newisec->sid = isec->sid; 3113 newisec->initialized = 1; 3114 3115 return 0; 3116 } 3117 3118 static int selinux_socket_sendmsg(struct socket *sock, struct msghdr *msg, 3119 int size) 3120 { 3121 return socket_has_perm(current, sock, SOCKET__WRITE); 3122 } 3123 3124 static int selinux_socket_recvmsg(struct socket *sock, struct msghdr *msg, 3125 int size, int flags) 3126 { 3127 return socket_has_perm(current, sock, SOCKET__READ); 3128 } 3129 3130 static int selinux_socket_getsockname(struct socket *sock) 3131 { 3132 return socket_has_perm(current, sock, SOCKET__GETATTR); 3133 } 3134 3135 static int selinux_socket_getpeername(struct socket *sock) 3136 { 3137 return socket_has_perm(current, sock, SOCKET__GETATTR); 3138 } 3139 3140 static int selinux_socket_setsockopt(struct socket *sock,int level,int optname) 3141 { 3142 return socket_has_perm(current, sock, SOCKET__SETOPT); 3143 } 3144 3145 static int selinux_socket_getsockopt(struct socket *sock, int level, 3146 int optname) 3147 { 3148 return socket_has_perm(current, sock, SOCKET__GETOPT); 3149 } 3150 3151 static int selinux_socket_shutdown(struct socket *sock, int how) 3152 { 3153 return socket_has_perm(current, sock, SOCKET__SHUTDOWN); 3154 } 3155 3156 static int selinux_socket_unix_stream_connect(struct socket *sock, 3157 struct socket *other, 3158 struct sock *newsk) 3159 { 3160 struct sk_security_struct *ssec; 3161 struct inode_security_struct *isec; 3162 struct inode_security_struct *other_isec; 3163 struct avc_audit_data ad; 3164 int err; 3165 3166 err = secondary_ops->unix_stream_connect(sock, other, newsk); 3167 if (err) 3168 return err; 3169 3170 isec = SOCK_INODE(sock)->i_security; 3171 other_isec = SOCK_INODE(other)->i_security; 3172 3173 AVC_AUDIT_DATA_INIT(&ad,NET); 3174 ad.u.net.sk = other->sk; 3175 3176 err = avc_has_perm(isec->sid, other_isec->sid, 3177 isec->sclass, 3178 UNIX_STREAM_SOCKET__CONNECTTO, &ad); 3179 if (err) 3180 return err; 3181 3182 /* connecting socket */ 3183 ssec = sock->sk->sk_security; 3184 ssec->peer_sid = other_isec->sid; 3185 3186 /* server child socket */ 3187 ssec = newsk->sk_security; 3188 ssec->peer_sid = isec->sid; 3189 3190 return 0; 3191 } 3192 3193 static int selinux_socket_unix_may_send(struct socket *sock, 3194 struct socket *other) 3195 { 3196 struct inode_security_struct *isec; 3197 struct inode_security_struct *other_isec; 3198 struct avc_audit_data ad; 3199 int err; 3200 3201 isec = SOCK_INODE(sock)->i_security; 3202 other_isec = SOCK_INODE(other)->i_security; 3203 3204 AVC_AUDIT_DATA_INIT(&ad,NET); 3205 ad.u.net.sk = other->sk; 3206 3207 err = avc_has_perm(isec->sid, other_isec->sid, 3208 isec->sclass, SOCKET__SENDTO, &ad); 3209 if (err) 3210 return err; 3211 3212 return 0; 3213 } 3214 3215 static int selinux_socket_sock_rcv_skb(struct sock *sk, struct sk_buff *skb) 3216 { 3217 u16 family; 3218 char *addrp; 3219 int len, err = 0; 3220 u32 netif_perm, node_perm, node_sid, if_sid, recv_perm = 0; 3221 u32 sock_sid = 0; 3222 u16 sock_class = 0; 3223 struct socket *sock; 3224 struct net_device *dev; 3225 struct avc_audit_data ad; 3226 3227 family = sk->sk_family; 3228 if (family != PF_INET && family != PF_INET6) 3229 goto out; 3230 3231 /* Handle mapped IPv4 packets arriving via IPv6 sockets */ 3232 if (family == PF_INET6 && skb->protocol == ntohs(ETH_P_IP)) 3233 family = PF_INET; 3234 3235 read_lock_bh(&sk->sk_callback_lock); 3236 sock = sk->sk_socket; 3237 if (sock) { 3238 struct inode *inode; 3239 inode = SOCK_INODE(sock); 3240 if (inode) { 3241 struct inode_security_struct *isec; 3242 isec = inode->i_security; 3243 sock_sid = isec->sid; 3244 sock_class = isec->sclass; 3245 } 3246 } 3247 read_unlock_bh(&sk->sk_callback_lock); 3248 if (!sock_sid) 3249 goto out; 3250 3251 dev = skb->dev; 3252 if (!dev) 3253 goto out; 3254 3255 err = sel_netif_sids(dev, &if_sid, NULL); 3256 if (err) 3257 goto out; 3258 3259 switch (sock_class) { 3260 case SECCLASS_UDP_SOCKET: 3261 netif_perm = NETIF__UDP_RECV; 3262 node_perm = NODE__UDP_RECV; 3263 recv_perm = UDP_SOCKET__RECV_MSG; 3264 break; 3265 3266 case SECCLASS_TCP_SOCKET: 3267 netif_perm = NETIF__TCP_RECV; 3268 node_perm = NODE__TCP_RECV; 3269 recv_perm = TCP_SOCKET__RECV_MSG; 3270 break; 3271 3272 default: 3273 netif_perm = NETIF__RAWIP_RECV; 3274 node_perm = NODE__RAWIP_RECV; 3275 break; 3276 } 3277 3278 AVC_AUDIT_DATA_INIT(&ad, NET); 3279 ad.u.net.netif = dev->name; 3280 ad.u.net.family = family; 3281 3282 err = selinux_parse_skb(skb, &ad, &addrp, &len, 1); 3283 if (err) 3284 goto out; 3285 3286 err = avc_has_perm(sock_sid, if_sid, SECCLASS_NETIF, netif_perm, &ad); 3287 if (err) 3288 goto out; 3289 3290 /* Fixme: this lookup is inefficient */ 3291 err = security_node_sid(family, addrp, len, &node_sid); 3292 if (err) 3293 goto out; 3294 3295 err = avc_has_perm(sock_sid, node_sid, SECCLASS_NODE, node_perm, &ad); 3296 if (err) 3297 goto out; 3298 3299 if (recv_perm) { 3300 u32 port_sid; 3301 3302 /* Fixme: make this more efficient */ 3303 err = security_port_sid(sk->sk_family, sk->sk_type, 3304 sk->sk_protocol, ntohs(ad.u.net.sport), 3305 &port_sid); 3306 if (err) 3307 goto out; 3308 3309 err = avc_has_perm(sock_sid, port_sid, 3310 sock_class, recv_perm, &ad); 3311 } 3312 3313 if (!err) 3314 err = selinux_xfrm_sock_rcv_skb(sock_sid, skb); 3315 3316 out: 3317 return err; 3318 } 3319 3320 static int selinux_socket_getpeersec_stream(struct socket *sock, char __user *optval, 3321 int __user *optlen, unsigned len) 3322 { 3323 int err = 0; 3324 char *scontext; 3325 u32 scontext_len; 3326 struct sk_security_struct *ssec; 3327 struct inode_security_struct *isec; 3328 u32 peer_sid = 0; 3329 3330 isec = SOCK_INODE(sock)->i_security; 3331 3332 /* if UNIX_STREAM check peer_sid, if TCP check dst for labelled sa */ 3333 if (isec->sclass == SECCLASS_UNIX_STREAM_SOCKET) { 3334 ssec = sock->sk->sk_security; 3335 peer_sid = ssec->peer_sid; 3336 } 3337 else if (isec->sclass == SECCLASS_TCP_SOCKET) { 3338 peer_sid = selinux_socket_getpeer_stream(sock->sk); 3339 3340 if (peer_sid == SECSID_NULL) { 3341 err = -ENOPROTOOPT; 3342 goto out; 3343 } 3344 } 3345 else { 3346 err = -ENOPROTOOPT; 3347 goto out; 3348 } 3349 3350 err = security_sid_to_context(peer_sid, &scontext, &scontext_len); 3351 3352 if (err) 3353 goto out; 3354 3355 if (scontext_len > len) { 3356 err = -ERANGE; 3357 goto out_len; 3358 } 3359 3360 if (copy_to_user(optval, scontext, scontext_len)) 3361 err = -EFAULT; 3362 3363 out_len: 3364 if (put_user(scontext_len, optlen)) 3365 err = -EFAULT; 3366 3367 kfree(scontext); 3368 out: 3369 return err; 3370 } 3371 3372 static int selinux_socket_getpeersec_dgram(struct sk_buff *skb, char **secdata, u32 *seclen) 3373 { 3374 int err = 0; 3375 u32 peer_sid = selinux_socket_getpeer_dgram(skb); 3376 3377 if (peer_sid == SECSID_NULL) 3378 return -EINVAL; 3379 3380 err = security_sid_to_context(peer_sid, secdata, seclen); 3381 if (err) 3382 return err; 3383 3384 return 0; 3385 } 3386 3387 3388 3389 static int selinux_sk_alloc_security(struct sock *sk, int family, gfp_t priority) 3390 { 3391 return sk_alloc_security(sk, family, priority); 3392 } 3393 3394 static void selinux_sk_free_security(struct sock *sk) 3395 { 3396 sk_free_security(sk); 3397 } 3398 3399 static unsigned int selinux_sk_getsid_security(struct sock *sk, struct flowi *fl, u8 dir) 3400 { 3401 struct inode_security_struct *isec; 3402 u32 sock_sid = SECINITSID_ANY_SOCKET; 3403 3404 if (!sk) 3405 return selinux_no_sk_sid(fl); 3406 3407 read_lock_bh(&sk->sk_callback_lock); 3408 isec = get_sock_isec(sk); 3409 3410 if (isec) 3411 sock_sid = isec->sid; 3412 3413 read_unlock_bh(&sk->sk_callback_lock); 3414 return sock_sid; 3415 } 3416 3417 static int selinux_nlmsg_perm(struct sock *sk, struct sk_buff *skb) 3418 { 3419 int err = 0; 3420 u32 perm; 3421 struct nlmsghdr *nlh; 3422 struct socket *sock = sk->sk_socket; 3423 struct inode_security_struct *isec = SOCK_INODE(sock)->i_security; 3424 3425 if (skb->len < NLMSG_SPACE(0)) { 3426 err = -EINVAL; 3427 goto out; 3428 } 3429 nlh = (struct nlmsghdr *)skb->data; 3430 3431 err = selinux_nlmsg_lookup(isec->sclass, nlh->nlmsg_type, &perm); 3432 if (err) { 3433 if (err == -EINVAL) { 3434 audit_log(current->audit_context, GFP_KERNEL, AUDIT_SELINUX_ERR, 3435 "SELinux: unrecognized netlink message" 3436 " type=%hu for sclass=%hu\n", 3437 nlh->nlmsg_type, isec->sclass); 3438 if (!selinux_enforcing) 3439 err = 0; 3440 } 3441 3442 /* Ignore */ 3443 if (err == -ENOENT) 3444 err = 0; 3445 goto out; 3446 } 3447 3448 err = socket_has_perm(current, sock, perm); 3449 out: 3450 return err; 3451 } 3452 3453 #ifdef CONFIG_NETFILTER 3454 3455 static unsigned int selinux_ip_postroute_last(unsigned int hooknum, 3456 struct sk_buff **pskb, 3457 const struct net_device *in, 3458 const struct net_device *out, 3459 int (*okfn)(struct sk_buff *), 3460 u16 family) 3461 { 3462 char *addrp; 3463 int len, err = NF_ACCEPT; 3464 u32 netif_perm, node_perm, node_sid, if_sid, send_perm = 0; 3465 struct sock *sk; 3466 struct socket *sock; 3467 struct inode *inode; 3468 struct sk_buff *skb = *pskb; 3469 struct inode_security_struct *isec; 3470 struct avc_audit_data ad; 3471 struct net_device *dev = (struct net_device *)out; 3472 3473 sk = skb->sk; 3474 if (!sk) 3475 goto out; 3476 3477 sock = sk->sk_socket; 3478 if (!sock) 3479 goto out; 3480 3481 inode = SOCK_INODE(sock); 3482 if (!inode) 3483 goto out; 3484 3485 err = sel_netif_sids(dev, &if_sid, NULL); 3486 if (err) 3487 goto out; 3488 3489 isec = inode->i_security; 3490 3491 switch (isec->sclass) { 3492 case SECCLASS_UDP_SOCKET: 3493 netif_perm = NETIF__UDP_SEND; 3494 node_perm = NODE__UDP_SEND; 3495 send_perm = UDP_SOCKET__SEND_MSG; 3496 break; 3497 3498 case SECCLASS_TCP_SOCKET: 3499 netif_perm = NETIF__TCP_SEND; 3500 node_perm = NODE__TCP_SEND; 3501 send_perm = TCP_SOCKET__SEND_MSG; 3502 break; 3503 3504 default: 3505 netif_perm = NETIF__RAWIP_SEND; 3506 node_perm = NODE__RAWIP_SEND; 3507 break; 3508 } 3509 3510 3511 AVC_AUDIT_DATA_INIT(&ad, NET); 3512 ad.u.net.netif = dev->name; 3513 ad.u.net.family = family; 3514 3515 err = selinux_parse_skb(skb, &ad, &addrp, 3516 &len, 0) ? NF_DROP : NF_ACCEPT; 3517 if (err != NF_ACCEPT) 3518 goto out; 3519 3520 err = avc_has_perm(isec->sid, if_sid, SECCLASS_NETIF, 3521 netif_perm, &ad) ? NF_DROP : NF_ACCEPT; 3522 if (err != NF_ACCEPT) 3523 goto out; 3524 3525 /* Fixme: this lookup is inefficient */ 3526 err = security_node_sid(family, addrp, len, 3527 &node_sid) ? NF_DROP : NF_ACCEPT; 3528 if (err != NF_ACCEPT) 3529 goto out; 3530 3531 err = avc_has_perm(isec->sid, node_sid, SECCLASS_NODE, 3532 node_perm, &ad) ? NF_DROP : NF_ACCEPT; 3533 if (err != NF_ACCEPT) 3534 goto out; 3535 3536 if (send_perm) { 3537 u32 port_sid; 3538 3539 /* Fixme: make this more efficient */ 3540 err = security_port_sid(sk->sk_family, 3541 sk->sk_type, 3542 sk->sk_protocol, 3543 ntohs(ad.u.net.dport), 3544 &port_sid) ? NF_DROP : NF_ACCEPT; 3545 if (err != NF_ACCEPT) 3546 goto out; 3547 3548 err = avc_has_perm(isec->sid, port_sid, isec->sclass, 3549 send_perm, &ad) ? NF_DROP : NF_ACCEPT; 3550 } 3551 3552 if (err != NF_ACCEPT) 3553 goto out; 3554 3555 err = selinux_xfrm_postroute_last(isec->sid, skb); 3556 3557 out: 3558 return err; 3559 } 3560 3561 static unsigned int selinux_ipv4_postroute_last(unsigned int hooknum, 3562 struct sk_buff **pskb, 3563 const struct net_device *in, 3564 const struct net_device *out, 3565 int (*okfn)(struct sk_buff *)) 3566 { 3567 return selinux_ip_postroute_last(hooknum, pskb, in, out, okfn, PF_INET); 3568 } 3569 3570 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE) 3571 3572 static unsigned int selinux_ipv6_postroute_last(unsigned int hooknum, 3573 struct sk_buff **pskb, 3574 const struct net_device *in, 3575 const struct net_device *out, 3576 int (*okfn)(struct sk_buff *)) 3577 { 3578 return selinux_ip_postroute_last(hooknum, pskb, in, out, okfn, PF_INET6); 3579 } 3580 3581 #endif /* IPV6 */ 3582 3583 #endif /* CONFIG_NETFILTER */ 3584 3585 static int selinux_netlink_send(struct sock *sk, struct sk_buff *skb) 3586 { 3587 struct task_security_struct *tsec; 3588 struct av_decision avd; 3589 int err; 3590 3591 err = secondary_ops->netlink_send(sk, skb); 3592 if (err) 3593 return err; 3594 3595 tsec = current->security; 3596 3597 avd.allowed = 0; 3598 avc_has_perm_noaudit(tsec->sid, tsec->sid, 3599 SECCLASS_CAPABILITY, ~0, &avd); 3600 cap_mask(NETLINK_CB(skb).eff_cap, avd.allowed); 3601 3602 if (policydb_loaded_version >= POLICYDB_VERSION_NLCLASS) 3603 err = selinux_nlmsg_perm(sk, skb); 3604 3605 return err; 3606 } 3607 3608 static int selinux_netlink_recv(struct sk_buff *skb) 3609 { 3610 if (!cap_raised(NETLINK_CB(skb).eff_cap, CAP_NET_ADMIN)) 3611 return -EPERM; 3612 return 0; 3613 } 3614 3615 static int ipc_alloc_security(struct task_struct *task, 3616 struct kern_ipc_perm *perm, 3617 u16 sclass) 3618 { 3619 struct task_security_struct *tsec = task->security; 3620 struct ipc_security_struct *isec; 3621 3622 isec = kzalloc(sizeof(struct ipc_security_struct), GFP_KERNEL); 3623 if (!isec) 3624 return -ENOMEM; 3625 3626 isec->sclass = sclass; 3627 isec->ipc_perm = perm; 3628 isec->sid = tsec->sid; 3629 perm->security = isec; 3630 3631 return 0; 3632 } 3633 3634 static void ipc_free_security(struct kern_ipc_perm *perm) 3635 { 3636 struct ipc_security_struct *isec = perm->security; 3637 perm->security = NULL; 3638 kfree(isec); 3639 } 3640 3641 static int msg_msg_alloc_security(struct msg_msg *msg) 3642 { 3643 struct msg_security_struct *msec; 3644 3645 msec = kzalloc(sizeof(struct msg_security_struct), GFP_KERNEL); 3646 if (!msec) 3647 return -ENOMEM; 3648 3649 msec->msg = msg; 3650 msec->sid = SECINITSID_UNLABELED; 3651 msg->security = msec; 3652 3653 return 0; 3654 } 3655 3656 static void msg_msg_free_security(struct msg_msg *msg) 3657 { 3658 struct msg_security_struct *msec = msg->security; 3659 3660 msg->security = NULL; 3661 kfree(msec); 3662 } 3663 3664 static int ipc_has_perm(struct kern_ipc_perm *ipc_perms, 3665 u32 perms) 3666 { 3667 struct task_security_struct *tsec; 3668 struct ipc_security_struct *isec; 3669 struct avc_audit_data ad; 3670 3671 tsec = current->security; 3672 isec = ipc_perms->security; 3673 3674 AVC_AUDIT_DATA_INIT(&ad, IPC); 3675 ad.u.ipc_id = ipc_perms->key; 3676 3677 return avc_has_perm(tsec->sid, isec->sid, isec->sclass, perms, &ad); 3678 } 3679 3680 static int selinux_msg_msg_alloc_security(struct msg_msg *msg) 3681 { 3682 return msg_msg_alloc_security(msg); 3683 } 3684 3685 static void selinux_msg_msg_free_security(struct msg_msg *msg) 3686 { 3687 msg_msg_free_security(msg); 3688 } 3689 3690 /* message queue security operations */ 3691 static int selinux_msg_queue_alloc_security(struct msg_queue *msq) 3692 { 3693 struct task_security_struct *tsec; 3694 struct ipc_security_struct *isec; 3695 struct avc_audit_data ad; 3696 int rc; 3697 3698 rc = ipc_alloc_security(current, &msq->q_perm, SECCLASS_MSGQ); 3699 if (rc) 3700 return rc; 3701 3702 tsec = current->security; 3703 isec = msq->q_perm.security; 3704 3705 AVC_AUDIT_DATA_INIT(&ad, IPC); 3706 ad.u.ipc_id = msq->q_perm.key; 3707 3708 rc = avc_has_perm(tsec->sid, isec->sid, SECCLASS_MSGQ, 3709 MSGQ__CREATE, &ad); 3710 if (rc) { 3711 ipc_free_security(&msq->q_perm); 3712 return rc; 3713 } 3714 return 0; 3715 } 3716 3717 static void selinux_msg_queue_free_security(struct msg_queue *msq) 3718 { 3719 ipc_free_security(&msq->q_perm); 3720 } 3721 3722 static int selinux_msg_queue_associate(struct msg_queue *msq, int msqflg) 3723 { 3724 struct task_security_struct *tsec; 3725 struct ipc_security_struct *isec; 3726 struct avc_audit_data ad; 3727 3728 tsec = current->security; 3729 isec = msq->q_perm.security; 3730 3731 AVC_AUDIT_DATA_INIT(&ad, IPC); 3732 ad.u.ipc_id = msq->q_perm.key; 3733 3734 return avc_has_perm(tsec->sid, isec->sid, SECCLASS_MSGQ, 3735 MSGQ__ASSOCIATE, &ad); 3736 } 3737 3738 static int selinux_msg_queue_msgctl(struct msg_queue *msq, int cmd) 3739 { 3740 int err; 3741 int perms; 3742 3743 switch(cmd) { 3744 case IPC_INFO: 3745 case MSG_INFO: 3746 /* No specific object, just general system-wide information. */ 3747 return task_has_system(current, SYSTEM__IPC_INFO); 3748 case IPC_STAT: 3749 case MSG_STAT: 3750 perms = MSGQ__GETATTR | MSGQ__ASSOCIATE; 3751 break; 3752 case IPC_SET: 3753 perms = MSGQ__SETATTR; 3754 break; 3755 case IPC_RMID: 3756 perms = MSGQ__DESTROY; 3757 break; 3758 default: 3759 return 0; 3760 } 3761 3762 err = ipc_has_perm(&msq->q_perm, perms); 3763 return err; 3764 } 3765 3766 static int selinux_msg_queue_msgsnd(struct msg_queue *msq, struct msg_msg *msg, int msqflg) 3767 { 3768 struct task_security_struct *tsec; 3769 struct ipc_security_struct *isec; 3770 struct msg_security_struct *msec; 3771 struct avc_audit_data ad; 3772 int rc; 3773 3774 tsec = current->security; 3775 isec = msq->q_perm.security; 3776 msec = msg->security; 3777 3778 /* 3779 * First time through, need to assign label to the message 3780 */ 3781 if (msec->sid == SECINITSID_UNLABELED) { 3782 /* 3783 * Compute new sid based on current process and 3784 * message queue this message will be stored in 3785 */ 3786 rc = security_transition_sid(tsec->sid, 3787 isec->sid, 3788 SECCLASS_MSG, 3789 &msec->sid); 3790 if (rc) 3791 return rc; 3792 } 3793 3794 AVC_AUDIT_DATA_INIT(&ad, IPC); 3795 ad.u.ipc_id = msq->q_perm.key; 3796 3797 /* Can this process write to the queue? */ 3798 rc = avc_has_perm(tsec->sid, isec->sid, SECCLASS_MSGQ, 3799 MSGQ__WRITE, &ad); 3800 if (!rc) 3801 /* Can this process send the message */ 3802 rc = avc_has_perm(tsec->sid, msec->sid, 3803 SECCLASS_MSG, MSG__SEND, &ad); 3804 if (!rc) 3805 /* Can the message be put in the queue? */ 3806 rc = avc_has_perm(msec->sid, isec->sid, 3807 SECCLASS_MSGQ, MSGQ__ENQUEUE, &ad); 3808 3809 return rc; 3810 } 3811 3812 static int selinux_msg_queue_msgrcv(struct msg_queue *msq, struct msg_msg *msg, 3813 struct task_struct *target, 3814 long type, int mode) 3815 { 3816 struct task_security_struct *tsec; 3817 struct ipc_security_struct *isec; 3818 struct msg_security_struct *msec; 3819 struct avc_audit_data ad; 3820 int rc; 3821 3822 tsec = target->security; 3823 isec = msq->q_perm.security; 3824 msec = msg->security; 3825 3826 AVC_AUDIT_DATA_INIT(&ad, IPC); 3827 ad.u.ipc_id = msq->q_perm.key; 3828 3829 rc = avc_has_perm(tsec->sid, isec->sid, 3830 SECCLASS_MSGQ, MSGQ__READ, &ad); 3831 if (!rc) 3832 rc = avc_has_perm(tsec->sid, msec->sid, 3833 SECCLASS_MSG, MSG__RECEIVE, &ad); 3834 return rc; 3835 } 3836 3837 /* Shared Memory security operations */ 3838 static int selinux_shm_alloc_security(struct shmid_kernel *shp) 3839 { 3840 struct task_security_struct *tsec; 3841 struct ipc_security_struct *isec; 3842 struct avc_audit_data ad; 3843 int rc; 3844 3845 rc = ipc_alloc_security(current, &shp->shm_perm, SECCLASS_SHM); 3846 if (rc) 3847 return rc; 3848 3849 tsec = current->security; 3850 isec = shp->shm_perm.security; 3851 3852 AVC_AUDIT_DATA_INIT(&ad, IPC); 3853 ad.u.ipc_id = shp->shm_perm.key; 3854 3855 rc = avc_has_perm(tsec->sid, isec->sid, SECCLASS_SHM, 3856 SHM__CREATE, &ad); 3857 if (rc) { 3858 ipc_free_security(&shp->shm_perm); 3859 return rc; 3860 } 3861 return 0; 3862 } 3863 3864 static void selinux_shm_free_security(struct shmid_kernel *shp) 3865 { 3866 ipc_free_security(&shp->shm_perm); 3867 } 3868 3869 static int selinux_shm_associate(struct shmid_kernel *shp, int shmflg) 3870 { 3871 struct task_security_struct *tsec; 3872 struct ipc_security_struct *isec; 3873 struct avc_audit_data ad; 3874 3875 tsec = current->security; 3876 isec = shp->shm_perm.security; 3877 3878 AVC_AUDIT_DATA_INIT(&ad, IPC); 3879 ad.u.ipc_id = shp->shm_perm.key; 3880 3881 return avc_has_perm(tsec->sid, isec->sid, SECCLASS_SHM, 3882 SHM__ASSOCIATE, &ad); 3883 } 3884 3885 /* Note, at this point, shp is locked down */ 3886 static int selinux_shm_shmctl(struct shmid_kernel *shp, int cmd) 3887 { 3888 int perms; 3889 int err; 3890 3891 switch(cmd) { 3892 case IPC_INFO: 3893 case SHM_INFO: 3894 /* No specific object, just general system-wide information. */ 3895 return task_has_system(current, SYSTEM__IPC_INFO); 3896 case IPC_STAT: 3897 case SHM_STAT: 3898 perms = SHM__GETATTR | SHM__ASSOCIATE; 3899 break; 3900 case IPC_SET: 3901 perms = SHM__SETATTR; 3902 break; 3903 case SHM_LOCK: 3904 case SHM_UNLOCK: 3905 perms = SHM__LOCK; 3906 break; 3907 case IPC_RMID: 3908 perms = SHM__DESTROY; 3909 break; 3910 default: 3911 return 0; 3912 } 3913 3914 err = ipc_has_perm(&shp->shm_perm, perms); 3915 return err; 3916 } 3917 3918 static int selinux_shm_shmat(struct shmid_kernel *shp, 3919 char __user *shmaddr, int shmflg) 3920 { 3921 u32 perms; 3922 int rc; 3923 3924 rc = secondary_ops->shm_shmat(shp, shmaddr, shmflg); 3925 if (rc) 3926 return rc; 3927 3928 if (shmflg & SHM_RDONLY) 3929 perms = SHM__READ; 3930 else 3931 perms = SHM__READ | SHM__WRITE; 3932 3933 return ipc_has_perm(&shp->shm_perm, perms); 3934 } 3935 3936 /* Semaphore security operations */ 3937 static int selinux_sem_alloc_security(struct sem_array *sma) 3938 { 3939 struct task_security_struct *tsec; 3940 struct ipc_security_struct *isec; 3941 struct avc_audit_data ad; 3942 int rc; 3943 3944 rc = ipc_alloc_security(current, &sma->sem_perm, SECCLASS_SEM); 3945 if (rc) 3946 return rc; 3947 3948 tsec = current->security; 3949 isec = sma->sem_perm.security; 3950 3951 AVC_AUDIT_DATA_INIT(&ad, IPC); 3952 ad.u.ipc_id = sma->sem_perm.key; 3953 3954 rc = avc_has_perm(tsec->sid, isec->sid, SECCLASS_SEM, 3955 SEM__CREATE, &ad); 3956 if (rc) { 3957 ipc_free_security(&sma->sem_perm); 3958 return rc; 3959 } 3960 return 0; 3961 } 3962 3963 static void selinux_sem_free_security(struct sem_array *sma) 3964 { 3965 ipc_free_security(&sma->sem_perm); 3966 } 3967 3968 static int selinux_sem_associate(struct sem_array *sma, int semflg) 3969 { 3970 struct task_security_struct *tsec; 3971 struct ipc_security_struct *isec; 3972 struct avc_audit_data ad; 3973 3974 tsec = current->security; 3975 isec = sma->sem_perm.security; 3976 3977 AVC_AUDIT_DATA_INIT(&ad, IPC); 3978 ad.u.ipc_id = sma->sem_perm.key; 3979 3980 return avc_has_perm(tsec->sid, isec->sid, SECCLASS_SEM, 3981 SEM__ASSOCIATE, &ad); 3982 } 3983 3984 /* Note, at this point, sma is locked down */ 3985 static int selinux_sem_semctl(struct sem_array *sma, int cmd) 3986 { 3987 int err; 3988 u32 perms; 3989 3990 switch(cmd) { 3991 case IPC_INFO: 3992 case SEM_INFO: 3993 /* No specific object, just general system-wide information. */ 3994 return task_has_system(current, SYSTEM__IPC_INFO); 3995 case GETPID: 3996 case GETNCNT: 3997 case GETZCNT: 3998 perms = SEM__GETATTR; 3999 break; 4000 case GETVAL: 4001 case GETALL: 4002 perms = SEM__READ; 4003 break; 4004 case SETVAL: 4005 case SETALL: 4006 perms = SEM__WRITE; 4007 break; 4008 case IPC_RMID: 4009 perms = SEM__DESTROY; 4010 break; 4011 case IPC_SET: 4012 perms = SEM__SETATTR; 4013 break; 4014 case IPC_STAT: 4015 case SEM_STAT: 4016 perms = SEM__GETATTR | SEM__ASSOCIATE; 4017 break; 4018 default: 4019 return 0; 4020 } 4021 4022 err = ipc_has_perm(&sma->sem_perm, perms); 4023 return err; 4024 } 4025 4026 static int selinux_sem_semop(struct sem_array *sma, 4027 struct sembuf *sops, unsigned nsops, int alter) 4028 { 4029 u32 perms; 4030 4031 if (alter) 4032 perms = SEM__READ | SEM__WRITE; 4033 else 4034 perms = SEM__READ; 4035 4036 return ipc_has_perm(&sma->sem_perm, perms); 4037 } 4038 4039 static int selinux_ipc_permission(struct kern_ipc_perm *ipcp, short flag) 4040 { 4041 u32 av = 0; 4042 4043 av = 0; 4044 if (flag & S_IRUGO) 4045 av |= IPC__UNIX_READ; 4046 if (flag & S_IWUGO) 4047 av |= IPC__UNIX_WRITE; 4048 4049 if (av == 0) 4050 return 0; 4051 4052 return ipc_has_perm(ipcp, av); 4053 } 4054 4055 static int selinux_ipc_getsecurity(struct kern_ipc_perm *ipcp, void *buffer, size_t size) 4056 { 4057 struct ipc_security_struct *isec = ipcp->security; 4058 4059 return selinux_getsecurity(isec->sid, buffer, size); 4060 } 4061 4062 /* module stacking operations */ 4063 static int selinux_register_security (const char *name, struct security_operations *ops) 4064 { 4065 if (secondary_ops != original_ops) { 4066 printk(KERN_INFO "%s: There is already a secondary security " 4067 "module registered.\n", __FUNCTION__); 4068 return -EINVAL; 4069 } 4070 4071 secondary_ops = ops; 4072 4073 printk(KERN_INFO "%s: Registering secondary module %s\n", 4074 __FUNCTION__, 4075 name); 4076 4077 return 0; 4078 } 4079 4080 static int selinux_unregister_security (const char *name, struct security_operations *ops) 4081 { 4082 if (ops != secondary_ops) { 4083 printk (KERN_INFO "%s: trying to unregister a security module " 4084 "that is not registered.\n", __FUNCTION__); 4085 return -EINVAL; 4086 } 4087 4088 secondary_ops = original_ops; 4089 4090 return 0; 4091 } 4092 4093 static void selinux_d_instantiate (struct dentry *dentry, struct inode *inode) 4094 { 4095 if (inode) 4096 inode_doinit_with_dentry(inode, dentry); 4097 } 4098 4099 static int selinux_getprocattr(struct task_struct *p, 4100 char *name, void *value, size_t size) 4101 { 4102 struct task_security_struct *tsec; 4103 u32 sid; 4104 int error; 4105 4106 if (current != p) { 4107 error = task_has_perm(current, p, PROCESS__GETATTR); 4108 if (error) 4109 return error; 4110 } 4111 4112 tsec = p->security; 4113 4114 if (!strcmp(name, "current")) 4115 sid = tsec->sid; 4116 else if (!strcmp(name, "prev")) 4117 sid = tsec->osid; 4118 else if (!strcmp(name, "exec")) 4119 sid = tsec->exec_sid; 4120 else if (!strcmp(name, "fscreate")) 4121 sid = tsec->create_sid; 4122 else 4123 return -EINVAL; 4124 4125 if (!sid) 4126 return 0; 4127 4128 return selinux_getsecurity(sid, value, size); 4129 } 4130 4131 static int selinux_setprocattr(struct task_struct *p, 4132 char *name, void *value, size_t size) 4133 { 4134 struct task_security_struct *tsec; 4135 u32 sid = 0; 4136 int error; 4137 char *str = value; 4138 4139 if (current != p) { 4140 /* SELinux only allows a process to change its own 4141 security attributes. */ 4142 return -EACCES; 4143 } 4144 4145 /* 4146 * Basic control over ability to set these attributes at all. 4147 * current == p, but we'll pass them separately in case the 4148 * above restriction is ever removed. 4149 */ 4150 if (!strcmp(name, "exec")) 4151 error = task_has_perm(current, p, PROCESS__SETEXEC); 4152 else if (!strcmp(name, "fscreate")) 4153 error = task_has_perm(current, p, PROCESS__SETFSCREATE); 4154 else if (!strcmp(name, "current")) 4155 error = task_has_perm(current, p, PROCESS__SETCURRENT); 4156 else 4157 error = -EINVAL; 4158 if (error) 4159 return error; 4160 4161 /* Obtain a SID for the context, if one was specified. */ 4162 if (size && str[1] && str[1] != '\n') { 4163 if (str[size-1] == '\n') { 4164 str[size-1] = 0; 4165 size--; 4166 } 4167 error = security_context_to_sid(value, size, &sid); 4168 if (error) 4169 return error; 4170 } 4171 4172 /* Permission checking based on the specified context is 4173 performed during the actual operation (execve, 4174 open/mkdir/...), when we know the full context of the 4175 operation. See selinux_bprm_set_security for the execve 4176 checks and may_create for the file creation checks. The 4177 operation will then fail if the context is not permitted. */ 4178 tsec = p->security; 4179 if (!strcmp(name, "exec")) 4180 tsec->exec_sid = sid; 4181 else if (!strcmp(name, "fscreate")) 4182 tsec->create_sid = sid; 4183 else if (!strcmp(name, "current")) { 4184 struct av_decision avd; 4185 4186 if (sid == 0) 4187 return -EINVAL; 4188 4189 /* Only allow single threaded processes to change context */ 4190 if (atomic_read(&p->mm->mm_users) != 1) { 4191 struct task_struct *g, *t; 4192 struct mm_struct *mm = p->mm; 4193 read_lock(&tasklist_lock); 4194 do_each_thread(g, t) 4195 if (t->mm == mm && t != p) { 4196 read_unlock(&tasklist_lock); 4197 return -EPERM; 4198 } 4199 while_each_thread(g, t); 4200 read_unlock(&tasklist_lock); 4201 } 4202 4203 /* Check permissions for the transition. */ 4204 error = avc_has_perm(tsec->sid, sid, SECCLASS_PROCESS, 4205 PROCESS__DYNTRANSITION, NULL); 4206 if (error) 4207 return error; 4208 4209 /* Check for ptracing, and update the task SID if ok. 4210 Otherwise, leave SID unchanged and fail. */ 4211 task_lock(p); 4212 if (p->ptrace & PT_PTRACED) { 4213 error = avc_has_perm_noaudit(tsec->ptrace_sid, sid, 4214 SECCLASS_PROCESS, 4215 PROCESS__PTRACE, &avd); 4216 if (!error) 4217 tsec->sid = sid; 4218 task_unlock(p); 4219 avc_audit(tsec->ptrace_sid, sid, SECCLASS_PROCESS, 4220 PROCESS__PTRACE, &avd, error, NULL); 4221 if (error) 4222 return error; 4223 } else { 4224 tsec->sid = sid; 4225 task_unlock(p); 4226 } 4227 } 4228 else 4229 return -EINVAL; 4230 4231 return size; 4232 } 4233 4234 static struct security_operations selinux_ops = { 4235 .ptrace = selinux_ptrace, 4236 .capget = selinux_capget, 4237 .capset_check = selinux_capset_check, 4238 .capset_set = selinux_capset_set, 4239 .sysctl = selinux_sysctl, 4240 .capable = selinux_capable, 4241 .quotactl = selinux_quotactl, 4242 .quota_on = selinux_quota_on, 4243 .syslog = selinux_syslog, 4244 .vm_enough_memory = selinux_vm_enough_memory, 4245 4246 .netlink_send = selinux_netlink_send, 4247 .netlink_recv = selinux_netlink_recv, 4248 4249 .bprm_alloc_security = selinux_bprm_alloc_security, 4250 .bprm_free_security = selinux_bprm_free_security, 4251 .bprm_apply_creds = selinux_bprm_apply_creds, 4252 .bprm_post_apply_creds = selinux_bprm_post_apply_creds, 4253 .bprm_set_security = selinux_bprm_set_security, 4254 .bprm_check_security = selinux_bprm_check_security, 4255 .bprm_secureexec = selinux_bprm_secureexec, 4256 4257 .sb_alloc_security = selinux_sb_alloc_security, 4258 .sb_free_security = selinux_sb_free_security, 4259 .sb_copy_data = selinux_sb_copy_data, 4260 .sb_kern_mount = selinux_sb_kern_mount, 4261 .sb_statfs = selinux_sb_statfs, 4262 .sb_mount = selinux_mount, 4263 .sb_umount = selinux_umount, 4264 4265 .inode_alloc_security = selinux_inode_alloc_security, 4266 .inode_free_security = selinux_inode_free_security, 4267 .inode_init_security = selinux_inode_init_security, 4268 .inode_create = selinux_inode_create, 4269 .inode_link = selinux_inode_link, 4270 .inode_unlink = selinux_inode_unlink, 4271 .inode_symlink = selinux_inode_symlink, 4272 .inode_mkdir = selinux_inode_mkdir, 4273 .inode_rmdir = selinux_inode_rmdir, 4274 .inode_mknod = selinux_inode_mknod, 4275 .inode_rename = selinux_inode_rename, 4276 .inode_readlink = selinux_inode_readlink, 4277 .inode_follow_link = selinux_inode_follow_link, 4278 .inode_permission = selinux_inode_permission, 4279 .inode_setattr = selinux_inode_setattr, 4280 .inode_getattr = selinux_inode_getattr, 4281 .inode_setxattr = selinux_inode_setxattr, 4282 .inode_post_setxattr = selinux_inode_post_setxattr, 4283 .inode_getxattr = selinux_inode_getxattr, 4284 .inode_listxattr = selinux_inode_listxattr, 4285 .inode_removexattr = selinux_inode_removexattr, 4286 .inode_xattr_getsuffix = selinux_inode_xattr_getsuffix, 4287 .inode_getsecurity = selinux_inode_getsecurity, 4288 .inode_setsecurity = selinux_inode_setsecurity, 4289 .inode_listsecurity = selinux_inode_listsecurity, 4290 4291 .file_permission = selinux_file_permission, 4292 .file_alloc_security = selinux_file_alloc_security, 4293 .file_free_security = selinux_file_free_security, 4294 .file_ioctl = selinux_file_ioctl, 4295 .file_mmap = selinux_file_mmap, 4296 .file_mprotect = selinux_file_mprotect, 4297 .file_lock = selinux_file_lock, 4298 .file_fcntl = selinux_file_fcntl, 4299 .file_set_fowner = selinux_file_set_fowner, 4300 .file_send_sigiotask = selinux_file_send_sigiotask, 4301 .file_receive = selinux_file_receive, 4302 4303 .task_create = selinux_task_create, 4304 .task_alloc_security = selinux_task_alloc_security, 4305 .task_free_security = selinux_task_free_security, 4306 .task_setuid = selinux_task_setuid, 4307 .task_post_setuid = selinux_task_post_setuid, 4308 .task_setgid = selinux_task_setgid, 4309 .task_setpgid = selinux_task_setpgid, 4310 .task_getpgid = selinux_task_getpgid, 4311 .task_getsid = selinux_task_getsid, 4312 .task_setgroups = selinux_task_setgroups, 4313 .task_setnice = selinux_task_setnice, 4314 .task_setrlimit = selinux_task_setrlimit, 4315 .task_setscheduler = selinux_task_setscheduler, 4316 .task_getscheduler = selinux_task_getscheduler, 4317 .task_kill = selinux_task_kill, 4318 .task_wait = selinux_task_wait, 4319 .task_prctl = selinux_task_prctl, 4320 .task_reparent_to_init = selinux_task_reparent_to_init, 4321 .task_to_inode = selinux_task_to_inode, 4322 4323 .ipc_permission = selinux_ipc_permission, 4324 .ipc_getsecurity = selinux_ipc_getsecurity, 4325 4326 .msg_msg_alloc_security = selinux_msg_msg_alloc_security, 4327 .msg_msg_free_security = selinux_msg_msg_free_security, 4328 4329 .msg_queue_alloc_security = selinux_msg_queue_alloc_security, 4330 .msg_queue_free_security = selinux_msg_queue_free_security, 4331 .msg_queue_associate = selinux_msg_queue_associate, 4332 .msg_queue_msgctl = selinux_msg_queue_msgctl, 4333 .msg_queue_msgsnd = selinux_msg_queue_msgsnd, 4334 .msg_queue_msgrcv = selinux_msg_queue_msgrcv, 4335 4336 .shm_alloc_security = selinux_shm_alloc_security, 4337 .shm_free_security = selinux_shm_free_security, 4338 .shm_associate = selinux_shm_associate, 4339 .shm_shmctl = selinux_shm_shmctl, 4340 .shm_shmat = selinux_shm_shmat, 4341 4342 .sem_alloc_security = selinux_sem_alloc_security, 4343 .sem_free_security = selinux_sem_free_security, 4344 .sem_associate = selinux_sem_associate, 4345 .sem_semctl = selinux_sem_semctl, 4346 .sem_semop = selinux_sem_semop, 4347 4348 .register_security = selinux_register_security, 4349 .unregister_security = selinux_unregister_security, 4350 4351 .d_instantiate = selinux_d_instantiate, 4352 4353 .getprocattr = selinux_getprocattr, 4354 .setprocattr = selinux_setprocattr, 4355 4356 .unix_stream_connect = selinux_socket_unix_stream_connect, 4357 .unix_may_send = selinux_socket_unix_may_send, 4358 4359 .socket_create = selinux_socket_create, 4360 .socket_post_create = selinux_socket_post_create, 4361 .socket_bind = selinux_socket_bind, 4362 .socket_connect = selinux_socket_connect, 4363 .socket_listen = selinux_socket_listen, 4364 .socket_accept = selinux_socket_accept, 4365 .socket_sendmsg = selinux_socket_sendmsg, 4366 .socket_recvmsg = selinux_socket_recvmsg, 4367 .socket_getsockname = selinux_socket_getsockname, 4368 .socket_getpeername = selinux_socket_getpeername, 4369 .socket_getsockopt = selinux_socket_getsockopt, 4370 .socket_setsockopt = selinux_socket_setsockopt, 4371 .socket_shutdown = selinux_socket_shutdown, 4372 .socket_sock_rcv_skb = selinux_socket_sock_rcv_skb, 4373 .socket_getpeersec_stream = selinux_socket_getpeersec_stream, 4374 .socket_getpeersec_dgram = selinux_socket_getpeersec_dgram, 4375 .sk_alloc_security = selinux_sk_alloc_security, 4376 .sk_free_security = selinux_sk_free_security, 4377 .sk_getsid = selinux_sk_getsid_security, 4378 4379 #ifdef CONFIG_SECURITY_NETWORK_XFRM 4380 .xfrm_policy_alloc_security = selinux_xfrm_policy_alloc, 4381 .xfrm_policy_clone_security = selinux_xfrm_policy_clone, 4382 .xfrm_policy_free_security = selinux_xfrm_policy_free, 4383 .xfrm_state_alloc_security = selinux_xfrm_state_alloc, 4384 .xfrm_state_free_security = selinux_xfrm_state_free, 4385 .xfrm_policy_lookup = selinux_xfrm_policy_lookup, 4386 #endif 4387 }; 4388 4389 static __init int selinux_init(void) 4390 { 4391 struct task_security_struct *tsec; 4392 4393 if (!selinux_enabled) { 4394 printk(KERN_INFO "SELinux: Disabled at boot.\n"); 4395 return 0; 4396 } 4397 4398 printk(KERN_INFO "SELinux: Initializing.\n"); 4399 4400 /* Set the security state for the initial task. */ 4401 if (task_alloc_security(current)) 4402 panic("SELinux: Failed to initialize initial task.\n"); 4403 tsec = current->security; 4404 tsec->osid = tsec->sid = SECINITSID_KERNEL; 4405 4406 sel_inode_cache = kmem_cache_create("selinux_inode_security", 4407 sizeof(struct inode_security_struct), 4408 0, SLAB_PANIC, NULL, NULL); 4409 avc_init(); 4410 4411 original_ops = secondary_ops = security_ops; 4412 if (!secondary_ops) 4413 panic ("SELinux: No initial security operations\n"); 4414 if (register_security (&selinux_ops)) 4415 panic("SELinux: Unable to register with kernel.\n"); 4416 4417 if (selinux_enforcing) { 4418 printk(KERN_INFO "SELinux: Starting in enforcing mode\n"); 4419 } else { 4420 printk(KERN_INFO "SELinux: Starting in permissive mode\n"); 4421 } 4422 return 0; 4423 } 4424 4425 void selinux_complete_init(void) 4426 { 4427 printk(KERN_INFO "SELinux: Completing initialization.\n"); 4428 4429 /* Set up any superblocks initialized prior to the policy load. */ 4430 printk(KERN_INFO "SELinux: Setting up existing superblocks.\n"); 4431 spin_lock(&sb_security_lock); 4432 next_sb: 4433 if (!list_empty(&superblock_security_head)) { 4434 struct superblock_security_struct *sbsec = 4435 list_entry(superblock_security_head.next, 4436 struct superblock_security_struct, 4437 list); 4438 struct super_block *sb = sbsec->sb; 4439 spin_lock(&sb_lock); 4440 sb->s_count++; 4441 spin_unlock(&sb_lock); 4442 spin_unlock(&sb_security_lock); 4443 down_read(&sb->s_umount); 4444 if (sb->s_root) 4445 superblock_doinit(sb, NULL); 4446 drop_super(sb); 4447 spin_lock(&sb_security_lock); 4448 list_del_init(&sbsec->list); 4449 goto next_sb; 4450 } 4451 spin_unlock(&sb_security_lock); 4452 } 4453 4454 /* SELinux requires early initialization in order to label 4455 all processes and objects when they are created. */ 4456 security_initcall(selinux_init); 4457 4458 #if defined(CONFIG_NETFILTER) 4459 4460 static struct nf_hook_ops selinux_ipv4_op = { 4461 .hook = selinux_ipv4_postroute_last, 4462 .owner = THIS_MODULE, 4463 .pf = PF_INET, 4464 .hooknum = NF_IP_POST_ROUTING, 4465 .priority = NF_IP_PRI_SELINUX_LAST, 4466 }; 4467 4468 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE) 4469 4470 static struct nf_hook_ops selinux_ipv6_op = { 4471 .hook = selinux_ipv6_postroute_last, 4472 .owner = THIS_MODULE, 4473 .pf = PF_INET6, 4474 .hooknum = NF_IP6_POST_ROUTING, 4475 .priority = NF_IP6_PRI_SELINUX_LAST, 4476 }; 4477 4478 #endif /* IPV6 */ 4479 4480 static int __init selinux_nf_ip_init(void) 4481 { 4482 int err = 0; 4483 4484 if (!selinux_enabled) 4485 goto out; 4486 4487 printk(KERN_INFO "SELinux: Registering netfilter hooks\n"); 4488 4489 err = nf_register_hook(&selinux_ipv4_op); 4490 if (err) 4491 panic("SELinux: nf_register_hook for IPv4: error %d\n", err); 4492 4493 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE) 4494 4495 err = nf_register_hook(&selinux_ipv6_op); 4496 if (err) 4497 panic("SELinux: nf_register_hook for IPv6: error %d\n", err); 4498 4499 #endif /* IPV6 */ 4500 4501 out: 4502 return err; 4503 } 4504 4505 __initcall(selinux_nf_ip_init); 4506 4507 #ifdef CONFIG_SECURITY_SELINUX_DISABLE 4508 static void selinux_nf_ip_exit(void) 4509 { 4510 printk(KERN_INFO "SELinux: Unregistering netfilter hooks\n"); 4511 4512 nf_unregister_hook(&selinux_ipv4_op); 4513 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE) 4514 nf_unregister_hook(&selinux_ipv6_op); 4515 #endif /* IPV6 */ 4516 } 4517 #endif 4518 4519 #else /* CONFIG_NETFILTER */ 4520 4521 #ifdef CONFIG_SECURITY_SELINUX_DISABLE 4522 #define selinux_nf_ip_exit() 4523 #endif 4524 4525 #endif /* CONFIG_NETFILTER */ 4526 4527 #ifdef CONFIG_SECURITY_SELINUX_DISABLE 4528 int selinux_disable(void) 4529 { 4530 extern void exit_sel_fs(void); 4531 static int selinux_disabled = 0; 4532 4533 if (ss_initialized) { 4534 /* Not permitted after initial policy load. */ 4535 return -EINVAL; 4536 } 4537 4538 if (selinux_disabled) { 4539 /* Only do this once. */ 4540 return -EINVAL; 4541 } 4542 4543 printk(KERN_INFO "SELinux: Disabled at runtime.\n"); 4544 4545 selinux_disabled = 1; 4546 4547 /* Reset security_ops to the secondary module, dummy or capability. */ 4548 security_ops = secondary_ops; 4549 4550 /* Unregister netfilter hooks. */ 4551 selinux_nf_ip_exit(); 4552 4553 /* Unregister selinuxfs. */ 4554 exit_sel_fs(); 4555 4556 return 0; 4557 } 4558 #endif 4559 4560 4561