1 /* 2 * NSA Security-Enhanced Linux (SELinux) security module 3 * 4 * This file contains the SELinux hook function implementations. 5 * 6 * Authors: Stephen Smalley, <sds@epoch.ncsc.mil> 7 * Chris Vance, <cvance@nai.com> 8 * Wayne Salamon, <wsalamon@nai.com> 9 * James Morris <jmorris@redhat.com> 10 * 11 * Copyright (C) 2001,2002 Networks Associates Technology, Inc. 12 * Copyright (C) 2003 Red Hat, Inc., James Morris <jmorris@redhat.com> 13 * Copyright (C) 2004-2005 Trusted Computer Solutions, Inc. 14 * <dgoeddel@trustedcs.com> 15 * 16 * This program is free software; you can redistribute it and/or modify 17 * it under the terms of the GNU General Public License version 2, 18 * as published by the Free Software Foundation. 19 */ 20 21 #include <linux/config.h> 22 #include <linux/module.h> 23 #include <linux/init.h> 24 #include <linux/kernel.h> 25 #include <linux/ptrace.h> 26 #include <linux/errno.h> 27 #include <linux/sched.h> 28 #include <linux/security.h> 29 #include <linux/xattr.h> 30 #include <linux/capability.h> 31 #include <linux/unistd.h> 32 #include <linux/mm.h> 33 #include <linux/mman.h> 34 #include <linux/slab.h> 35 #include <linux/pagemap.h> 36 #include <linux/swap.h> 37 #include <linux/smp_lock.h> 38 #include <linux/spinlock.h> 39 #include <linux/syscalls.h> 40 #include <linux/file.h> 41 #include <linux/namei.h> 42 #include <linux/mount.h> 43 #include <linux/ext2_fs.h> 44 #include <linux/proc_fs.h> 45 #include <linux/kd.h> 46 #include <linux/netfilter_ipv4.h> 47 #include <linux/netfilter_ipv6.h> 48 #include <linux/tty.h> 49 #include <net/icmp.h> 50 #include <net/ip.h> /* for sysctl_local_port_range[] */ 51 #include <net/tcp.h> /* struct or_callable used in sock_rcv_skb */ 52 #include <asm/uaccess.h> 53 #include <asm/semaphore.h> 54 #include <asm/ioctls.h> 55 #include <linux/bitops.h> 56 #include <linux/interrupt.h> 57 #include <linux/netdevice.h> /* for network interface checks */ 58 #include <linux/netlink.h> 59 #include <linux/tcp.h> 60 #include <linux/udp.h> 61 #include <linux/quota.h> 62 #include <linux/un.h> /* for Unix socket types */ 63 #include <net/af_unix.h> /* for Unix socket types */ 64 #include <linux/parser.h> 65 #include <linux/nfs_mount.h> 66 #include <net/ipv6.h> 67 #include <linux/hugetlb.h> 68 #include <linux/personality.h> 69 #include <linux/sysctl.h> 70 #include <linux/audit.h> 71 #include <linux/string.h> 72 73 #include "avc.h" 74 #include "objsec.h" 75 #include "netif.h" 76 77 #define XATTR_SELINUX_SUFFIX "selinux" 78 #define XATTR_NAME_SELINUX XATTR_SECURITY_PREFIX XATTR_SELINUX_SUFFIX 79 80 extern unsigned int policydb_loaded_version; 81 extern int selinux_nlmsg_lookup(u16 sclass, u16 nlmsg_type, u32 *perm); 82 83 #ifdef CONFIG_SECURITY_SELINUX_DEVELOP 84 int selinux_enforcing = 0; 85 86 static int __init enforcing_setup(char *str) 87 { 88 selinux_enforcing = simple_strtol(str,NULL,0); 89 return 1; 90 } 91 __setup("enforcing=", enforcing_setup); 92 #endif 93 94 #ifdef CONFIG_SECURITY_SELINUX_BOOTPARAM 95 int selinux_enabled = CONFIG_SECURITY_SELINUX_BOOTPARAM_VALUE; 96 97 static int __init selinux_enabled_setup(char *str) 98 { 99 selinux_enabled = simple_strtol(str, NULL, 0); 100 return 1; 101 } 102 __setup("selinux=", selinux_enabled_setup); 103 #endif 104 105 /* Original (dummy) security module. */ 106 static struct security_operations *original_ops = NULL; 107 108 /* Minimal support for a secondary security module, 109 just to allow the use of the dummy or capability modules. 110 The owlsm module can alternatively be used as a secondary 111 module as long as CONFIG_OWLSM_FD is not enabled. */ 112 static struct security_operations *secondary_ops = NULL; 113 114 /* Lists of inode and superblock security structures initialized 115 before the policy was loaded. */ 116 static LIST_HEAD(superblock_security_head); 117 static DEFINE_SPINLOCK(sb_security_lock); 118 119 /* Allocate and free functions for each kind of security blob. */ 120 121 static int task_alloc_security(struct task_struct *task) 122 { 123 struct task_security_struct *tsec; 124 125 tsec = kmalloc(sizeof(struct task_security_struct), GFP_KERNEL); 126 if (!tsec) 127 return -ENOMEM; 128 129 memset(tsec, 0, sizeof(struct task_security_struct)); 130 tsec->magic = SELINUX_MAGIC; 131 tsec->task = task; 132 tsec->osid = tsec->sid = tsec->ptrace_sid = SECINITSID_UNLABELED; 133 task->security = tsec; 134 135 return 0; 136 } 137 138 static void task_free_security(struct task_struct *task) 139 { 140 struct task_security_struct *tsec = task->security; 141 142 if (!tsec || tsec->magic != SELINUX_MAGIC) 143 return; 144 145 task->security = NULL; 146 kfree(tsec); 147 } 148 149 static int inode_alloc_security(struct inode *inode) 150 { 151 struct task_security_struct *tsec = current->security; 152 struct inode_security_struct *isec; 153 154 isec = kmalloc(sizeof(struct inode_security_struct), GFP_KERNEL); 155 if (!isec) 156 return -ENOMEM; 157 158 memset(isec, 0, sizeof(struct inode_security_struct)); 159 init_MUTEX(&isec->sem); 160 INIT_LIST_HEAD(&isec->list); 161 isec->magic = SELINUX_MAGIC; 162 isec->inode = inode; 163 isec->sid = SECINITSID_UNLABELED; 164 isec->sclass = SECCLASS_FILE; 165 if (tsec && tsec->magic == SELINUX_MAGIC) 166 isec->task_sid = tsec->sid; 167 else 168 isec->task_sid = SECINITSID_UNLABELED; 169 inode->i_security = isec; 170 171 return 0; 172 } 173 174 static void inode_free_security(struct inode *inode) 175 { 176 struct inode_security_struct *isec = inode->i_security; 177 struct superblock_security_struct *sbsec = inode->i_sb->s_security; 178 179 if (!isec || isec->magic != SELINUX_MAGIC) 180 return; 181 182 spin_lock(&sbsec->isec_lock); 183 if (!list_empty(&isec->list)) 184 list_del_init(&isec->list); 185 spin_unlock(&sbsec->isec_lock); 186 187 inode->i_security = NULL; 188 kfree(isec); 189 } 190 191 static int file_alloc_security(struct file *file) 192 { 193 struct task_security_struct *tsec = current->security; 194 struct file_security_struct *fsec; 195 196 fsec = kmalloc(sizeof(struct file_security_struct), GFP_ATOMIC); 197 if (!fsec) 198 return -ENOMEM; 199 200 memset(fsec, 0, sizeof(struct file_security_struct)); 201 fsec->magic = SELINUX_MAGIC; 202 fsec->file = file; 203 if (tsec && tsec->magic == SELINUX_MAGIC) { 204 fsec->sid = tsec->sid; 205 fsec->fown_sid = tsec->sid; 206 } else { 207 fsec->sid = SECINITSID_UNLABELED; 208 fsec->fown_sid = SECINITSID_UNLABELED; 209 } 210 file->f_security = fsec; 211 212 return 0; 213 } 214 215 static void file_free_security(struct file *file) 216 { 217 struct file_security_struct *fsec = file->f_security; 218 219 if (!fsec || fsec->magic != SELINUX_MAGIC) 220 return; 221 222 file->f_security = NULL; 223 kfree(fsec); 224 } 225 226 static int superblock_alloc_security(struct super_block *sb) 227 { 228 struct superblock_security_struct *sbsec; 229 230 sbsec = kmalloc(sizeof(struct superblock_security_struct), GFP_KERNEL); 231 if (!sbsec) 232 return -ENOMEM; 233 234 memset(sbsec, 0, sizeof(struct superblock_security_struct)); 235 init_MUTEX(&sbsec->sem); 236 INIT_LIST_HEAD(&sbsec->list); 237 INIT_LIST_HEAD(&sbsec->isec_head); 238 spin_lock_init(&sbsec->isec_lock); 239 sbsec->magic = SELINUX_MAGIC; 240 sbsec->sb = sb; 241 sbsec->sid = SECINITSID_UNLABELED; 242 sbsec->def_sid = SECINITSID_FILE; 243 sb->s_security = sbsec; 244 245 return 0; 246 } 247 248 static void superblock_free_security(struct super_block *sb) 249 { 250 struct superblock_security_struct *sbsec = sb->s_security; 251 252 if (!sbsec || sbsec->magic != SELINUX_MAGIC) 253 return; 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 #ifdef CONFIG_SECURITY_NETWORK 265 static int sk_alloc_security(struct sock *sk, int family, int priority) 266 { 267 struct sk_security_struct *ssec; 268 269 if (family != PF_UNIX) 270 return 0; 271 272 ssec = kmalloc(sizeof(*ssec), priority); 273 if (!ssec) 274 return -ENOMEM; 275 276 memset(ssec, 0, sizeof(*ssec)); 277 ssec->magic = SELINUX_MAGIC; 278 ssec->sk = sk; 279 ssec->peer_sid = SECINITSID_UNLABELED; 280 sk->sk_security = ssec; 281 282 return 0; 283 } 284 285 static void sk_free_security(struct sock *sk) 286 { 287 struct sk_security_struct *ssec = sk->sk_security; 288 289 if (sk->sk_family != PF_UNIX || ssec->magic != SELINUX_MAGIC) 290 return; 291 292 sk->sk_security = NULL; 293 kfree(ssec); 294 } 295 #endif /* CONFIG_SECURITY_NETWORK */ 296 297 /* The security server must be initialized before 298 any labeling or access decisions can be provided. */ 299 extern int ss_initialized; 300 301 /* The file system's label must be initialized prior to use. */ 302 303 static char *labeling_behaviors[6] = { 304 "uses xattr", 305 "uses transition SIDs", 306 "uses task SIDs", 307 "uses genfs_contexts", 308 "not configured for labeling", 309 "uses mountpoint labeling", 310 }; 311 312 static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dentry); 313 314 static inline int inode_doinit(struct inode *inode) 315 { 316 return inode_doinit_with_dentry(inode, NULL); 317 } 318 319 enum { 320 Opt_context = 1, 321 Opt_fscontext = 2, 322 Opt_defcontext = 4, 323 }; 324 325 static match_table_t tokens = { 326 {Opt_context, "context=%s"}, 327 {Opt_fscontext, "fscontext=%s"}, 328 {Opt_defcontext, "defcontext=%s"}, 329 }; 330 331 #define SEL_MOUNT_FAIL_MSG "SELinux: duplicate or incompatible mount options\n" 332 333 static int try_context_mount(struct super_block *sb, void *data) 334 { 335 char *context = NULL, *defcontext = NULL; 336 const char *name; 337 u32 sid; 338 int alloc = 0, rc = 0, seen = 0; 339 struct task_security_struct *tsec = current->security; 340 struct superblock_security_struct *sbsec = sb->s_security; 341 342 if (!data) 343 goto out; 344 345 name = sb->s_type->name; 346 347 if (sb->s_type->fs_flags & FS_BINARY_MOUNTDATA) { 348 349 /* NFS we understand. */ 350 if (!strcmp(name, "nfs")) { 351 struct nfs_mount_data *d = data; 352 353 if (d->version < NFS_MOUNT_VERSION) 354 goto out; 355 356 if (d->context[0]) { 357 context = d->context; 358 seen |= Opt_context; 359 } 360 } else 361 goto out; 362 363 } else { 364 /* Standard string-based options. */ 365 char *p, *options = data; 366 367 while ((p = strsep(&options, ",")) != NULL) { 368 int token; 369 substring_t args[MAX_OPT_ARGS]; 370 371 if (!*p) 372 continue; 373 374 token = match_token(p, tokens, args); 375 376 switch (token) { 377 case Opt_context: 378 if (seen) { 379 rc = -EINVAL; 380 printk(KERN_WARNING SEL_MOUNT_FAIL_MSG); 381 goto out_free; 382 } 383 context = match_strdup(&args[0]); 384 if (!context) { 385 rc = -ENOMEM; 386 goto out_free; 387 } 388 if (!alloc) 389 alloc = 1; 390 seen |= Opt_context; 391 break; 392 393 case Opt_fscontext: 394 if (seen & (Opt_context|Opt_fscontext)) { 395 rc = -EINVAL; 396 printk(KERN_WARNING SEL_MOUNT_FAIL_MSG); 397 goto out_free; 398 } 399 context = match_strdup(&args[0]); 400 if (!context) { 401 rc = -ENOMEM; 402 goto out_free; 403 } 404 if (!alloc) 405 alloc = 1; 406 seen |= Opt_fscontext; 407 break; 408 409 case Opt_defcontext: 410 if (sbsec->behavior != SECURITY_FS_USE_XATTR) { 411 rc = -EINVAL; 412 printk(KERN_WARNING "SELinux: " 413 "defcontext option is invalid " 414 "for this filesystem type\n"); 415 goto out_free; 416 } 417 if (seen & (Opt_context|Opt_defcontext)) { 418 rc = -EINVAL; 419 printk(KERN_WARNING SEL_MOUNT_FAIL_MSG); 420 goto out_free; 421 } 422 defcontext = match_strdup(&args[0]); 423 if (!defcontext) { 424 rc = -ENOMEM; 425 goto out_free; 426 } 427 if (!alloc) 428 alloc = 1; 429 seen |= Opt_defcontext; 430 break; 431 432 default: 433 rc = -EINVAL; 434 printk(KERN_WARNING "SELinux: unknown mount " 435 "option\n"); 436 goto out_free; 437 438 } 439 } 440 } 441 442 if (!seen) 443 goto out; 444 445 if (context) { 446 rc = security_context_to_sid(context, strlen(context), &sid); 447 if (rc) { 448 printk(KERN_WARNING "SELinux: security_context_to_sid" 449 "(%s) failed for (dev %s, type %s) errno=%d\n", 450 context, sb->s_id, name, rc); 451 goto out_free; 452 } 453 454 rc = avc_has_perm(tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM, 455 FILESYSTEM__RELABELFROM, NULL); 456 if (rc) 457 goto out_free; 458 459 rc = avc_has_perm(tsec->sid, sid, SECCLASS_FILESYSTEM, 460 FILESYSTEM__RELABELTO, NULL); 461 if (rc) 462 goto out_free; 463 464 sbsec->sid = sid; 465 466 if (seen & Opt_context) 467 sbsec->behavior = SECURITY_FS_USE_MNTPOINT; 468 } 469 470 if (defcontext) { 471 rc = security_context_to_sid(defcontext, strlen(defcontext), &sid); 472 if (rc) { 473 printk(KERN_WARNING "SELinux: security_context_to_sid" 474 "(%s) failed for (dev %s, type %s) errno=%d\n", 475 defcontext, sb->s_id, name, rc); 476 goto out_free; 477 } 478 479 if (sid == sbsec->def_sid) 480 goto out_free; 481 482 rc = avc_has_perm(tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM, 483 FILESYSTEM__RELABELFROM, NULL); 484 if (rc) 485 goto out_free; 486 487 rc = avc_has_perm(sid, sbsec->sid, SECCLASS_FILESYSTEM, 488 FILESYSTEM__ASSOCIATE, NULL); 489 if (rc) 490 goto out_free; 491 492 sbsec->def_sid = sid; 493 } 494 495 out_free: 496 if (alloc) { 497 kfree(context); 498 kfree(defcontext); 499 } 500 out: 501 return rc; 502 } 503 504 static int superblock_doinit(struct super_block *sb, void *data) 505 { 506 struct superblock_security_struct *sbsec = sb->s_security; 507 struct dentry *root = sb->s_root; 508 struct inode *inode = root->d_inode; 509 int rc = 0; 510 511 down(&sbsec->sem); 512 if (sbsec->initialized) 513 goto out; 514 515 if (!ss_initialized) { 516 /* Defer initialization until selinux_complete_init, 517 after the initial policy is loaded and the security 518 server is ready to handle calls. */ 519 spin_lock(&sb_security_lock); 520 if (list_empty(&sbsec->list)) 521 list_add(&sbsec->list, &superblock_security_head); 522 spin_unlock(&sb_security_lock); 523 goto out; 524 } 525 526 /* Determine the labeling behavior to use for this filesystem type. */ 527 rc = security_fs_use(sb->s_type->name, &sbsec->behavior, &sbsec->sid); 528 if (rc) { 529 printk(KERN_WARNING "%s: security_fs_use(%s) returned %d\n", 530 __FUNCTION__, sb->s_type->name, rc); 531 goto out; 532 } 533 534 rc = try_context_mount(sb, data); 535 if (rc) 536 goto out; 537 538 if (sbsec->behavior == SECURITY_FS_USE_XATTR) { 539 /* Make sure that the xattr handler exists and that no 540 error other than -ENODATA is returned by getxattr on 541 the root directory. -ENODATA is ok, as this may be 542 the first boot of the SELinux kernel before we have 543 assigned xattr values to the filesystem. */ 544 if (!inode->i_op->getxattr) { 545 printk(KERN_WARNING "SELinux: (dev %s, type %s) has no " 546 "xattr support\n", sb->s_id, sb->s_type->name); 547 rc = -EOPNOTSUPP; 548 goto out; 549 } 550 rc = inode->i_op->getxattr(root, XATTR_NAME_SELINUX, NULL, 0); 551 if (rc < 0 && rc != -ENODATA) { 552 if (rc == -EOPNOTSUPP) 553 printk(KERN_WARNING "SELinux: (dev %s, type " 554 "%s) has no security xattr handler\n", 555 sb->s_id, sb->s_type->name); 556 else 557 printk(KERN_WARNING "SELinux: (dev %s, type " 558 "%s) getxattr errno %d\n", sb->s_id, 559 sb->s_type->name, -rc); 560 goto out; 561 } 562 } 563 564 if (strcmp(sb->s_type->name, "proc") == 0) 565 sbsec->proc = 1; 566 567 sbsec->initialized = 1; 568 569 if (sbsec->behavior > ARRAY_SIZE(labeling_behaviors)) { 570 printk(KERN_INFO "SELinux: initialized (dev %s, type %s), unknown behavior\n", 571 sb->s_id, sb->s_type->name); 572 } 573 else { 574 printk(KERN_INFO "SELinux: initialized (dev %s, type %s), %s\n", 575 sb->s_id, sb->s_type->name, 576 labeling_behaviors[sbsec->behavior-1]); 577 } 578 579 /* Initialize the root inode. */ 580 rc = inode_doinit_with_dentry(sb->s_root->d_inode, sb->s_root); 581 582 /* Initialize any other inodes associated with the superblock, e.g. 583 inodes created prior to initial policy load or inodes created 584 during get_sb by a pseudo filesystem that directly 585 populates itself. */ 586 spin_lock(&sbsec->isec_lock); 587 next_inode: 588 if (!list_empty(&sbsec->isec_head)) { 589 struct inode_security_struct *isec = 590 list_entry(sbsec->isec_head.next, 591 struct inode_security_struct, list); 592 struct inode *inode = isec->inode; 593 spin_unlock(&sbsec->isec_lock); 594 inode = igrab(inode); 595 if (inode) { 596 if (!IS_PRIVATE (inode)) 597 inode_doinit(inode); 598 iput(inode); 599 } 600 spin_lock(&sbsec->isec_lock); 601 list_del_init(&isec->list); 602 goto next_inode; 603 } 604 spin_unlock(&sbsec->isec_lock); 605 out: 606 up(&sbsec->sem); 607 return rc; 608 } 609 610 static inline u16 inode_mode_to_security_class(umode_t mode) 611 { 612 switch (mode & S_IFMT) { 613 case S_IFSOCK: 614 return SECCLASS_SOCK_FILE; 615 case S_IFLNK: 616 return SECCLASS_LNK_FILE; 617 case S_IFREG: 618 return SECCLASS_FILE; 619 case S_IFBLK: 620 return SECCLASS_BLK_FILE; 621 case S_IFDIR: 622 return SECCLASS_DIR; 623 case S_IFCHR: 624 return SECCLASS_CHR_FILE; 625 case S_IFIFO: 626 return SECCLASS_FIFO_FILE; 627 628 } 629 630 return SECCLASS_FILE; 631 } 632 633 static inline int default_protocol_stream(int protocol) 634 { 635 return (protocol == IPPROTO_IP || protocol == IPPROTO_TCP); 636 } 637 638 static inline int default_protocol_dgram(int protocol) 639 { 640 return (protocol == IPPROTO_IP || protocol == IPPROTO_UDP); 641 } 642 643 static inline u16 socket_type_to_security_class(int family, int type, int protocol) 644 { 645 switch (family) { 646 case PF_UNIX: 647 switch (type) { 648 case SOCK_STREAM: 649 case SOCK_SEQPACKET: 650 return SECCLASS_UNIX_STREAM_SOCKET; 651 case SOCK_DGRAM: 652 return SECCLASS_UNIX_DGRAM_SOCKET; 653 } 654 break; 655 case PF_INET: 656 case PF_INET6: 657 switch (type) { 658 case SOCK_STREAM: 659 if (default_protocol_stream(protocol)) 660 return SECCLASS_TCP_SOCKET; 661 else 662 return SECCLASS_RAWIP_SOCKET; 663 case SOCK_DGRAM: 664 if (default_protocol_dgram(protocol)) 665 return SECCLASS_UDP_SOCKET; 666 else 667 return SECCLASS_RAWIP_SOCKET; 668 default: 669 return SECCLASS_RAWIP_SOCKET; 670 } 671 break; 672 case PF_NETLINK: 673 switch (protocol) { 674 case NETLINK_ROUTE: 675 return SECCLASS_NETLINK_ROUTE_SOCKET; 676 case NETLINK_FIREWALL: 677 return SECCLASS_NETLINK_FIREWALL_SOCKET; 678 case NETLINK_INET_DIAG: 679 return SECCLASS_NETLINK_TCPDIAG_SOCKET; 680 case NETLINK_NFLOG: 681 return SECCLASS_NETLINK_NFLOG_SOCKET; 682 case NETLINK_XFRM: 683 return SECCLASS_NETLINK_XFRM_SOCKET; 684 case NETLINK_SELINUX: 685 return SECCLASS_NETLINK_SELINUX_SOCKET; 686 case NETLINK_AUDIT: 687 return SECCLASS_NETLINK_AUDIT_SOCKET; 688 case NETLINK_IP6_FW: 689 return SECCLASS_NETLINK_IP6FW_SOCKET; 690 case NETLINK_DNRTMSG: 691 return SECCLASS_NETLINK_DNRT_SOCKET; 692 case NETLINK_KOBJECT_UEVENT: 693 return SECCLASS_NETLINK_KOBJECT_UEVENT_SOCKET; 694 default: 695 return SECCLASS_NETLINK_SOCKET; 696 } 697 case PF_PACKET: 698 return SECCLASS_PACKET_SOCKET; 699 case PF_KEY: 700 return SECCLASS_KEY_SOCKET; 701 } 702 703 return SECCLASS_SOCKET; 704 } 705 706 #ifdef CONFIG_PROC_FS 707 static int selinux_proc_get_sid(struct proc_dir_entry *de, 708 u16 tclass, 709 u32 *sid) 710 { 711 int buflen, rc; 712 char *buffer, *path, *end; 713 714 buffer = (char*)__get_free_page(GFP_KERNEL); 715 if (!buffer) 716 return -ENOMEM; 717 718 buflen = PAGE_SIZE; 719 end = buffer+buflen; 720 *--end = '\0'; 721 buflen--; 722 path = end-1; 723 *path = '/'; 724 while (de && de != de->parent) { 725 buflen -= de->namelen + 1; 726 if (buflen < 0) 727 break; 728 end -= de->namelen; 729 memcpy(end, de->name, de->namelen); 730 *--end = '/'; 731 path = end; 732 de = de->parent; 733 } 734 rc = security_genfs_sid("proc", path, tclass, sid); 735 free_page((unsigned long)buffer); 736 return rc; 737 } 738 #else 739 static int selinux_proc_get_sid(struct proc_dir_entry *de, 740 u16 tclass, 741 u32 *sid) 742 { 743 return -EINVAL; 744 } 745 #endif 746 747 /* The inode's security attributes must be initialized before first use. */ 748 static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dentry) 749 { 750 struct superblock_security_struct *sbsec = NULL; 751 struct inode_security_struct *isec = inode->i_security; 752 u32 sid; 753 struct dentry *dentry; 754 #define INITCONTEXTLEN 255 755 char *context = NULL; 756 unsigned len = 0; 757 int rc = 0; 758 int hold_sem = 0; 759 760 if (isec->initialized) 761 goto out; 762 763 down(&isec->sem); 764 hold_sem = 1; 765 if (isec->initialized) 766 goto out; 767 768 sbsec = inode->i_sb->s_security; 769 if (!sbsec->initialized) { 770 /* Defer initialization until selinux_complete_init, 771 after the initial policy is loaded and the security 772 server is ready to handle calls. */ 773 spin_lock(&sbsec->isec_lock); 774 if (list_empty(&isec->list)) 775 list_add(&isec->list, &sbsec->isec_head); 776 spin_unlock(&sbsec->isec_lock); 777 goto out; 778 } 779 780 switch (sbsec->behavior) { 781 case SECURITY_FS_USE_XATTR: 782 if (!inode->i_op->getxattr) { 783 isec->sid = sbsec->def_sid; 784 break; 785 } 786 787 /* Need a dentry, since the xattr API requires one. 788 Life would be simpler if we could just pass the inode. */ 789 if (opt_dentry) { 790 /* Called from d_instantiate or d_splice_alias. */ 791 dentry = dget(opt_dentry); 792 } else { 793 /* Called from selinux_complete_init, try to find a dentry. */ 794 dentry = d_find_alias(inode); 795 } 796 if (!dentry) { 797 printk(KERN_WARNING "%s: no dentry for dev=%s " 798 "ino=%ld\n", __FUNCTION__, inode->i_sb->s_id, 799 inode->i_ino); 800 goto out; 801 } 802 803 len = INITCONTEXTLEN; 804 context = kmalloc(len, GFP_KERNEL); 805 if (!context) { 806 rc = -ENOMEM; 807 dput(dentry); 808 goto out; 809 } 810 rc = inode->i_op->getxattr(dentry, XATTR_NAME_SELINUX, 811 context, len); 812 if (rc == -ERANGE) { 813 /* Need a larger buffer. Query for the right size. */ 814 rc = inode->i_op->getxattr(dentry, XATTR_NAME_SELINUX, 815 NULL, 0); 816 if (rc < 0) { 817 dput(dentry); 818 goto out; 819 } 820 kfree(context); 821 len = rc; 822 context = kmalloc(len, GFP_KERNEL); 823 if (!context) { 824 rc = -ENOMEM; 825 dput(dentry); 826 goto out; 827 } 828 rc = inode->i_op->getxattr(dentry, 829 XATTR_NAME_SELINUX, 830 context, len); 831 } 832 dput(dentry); 833 if (rc < 0) { 834 if (rc != -ENODATA) { 835 printk(KERN_WARNING "%s: getxattr returned " 836 "%d for dev=%s ino=%ld\n", __FUNCTION__, 837 -rc, inode->i_sb->s_id, inode->i_ino); 838 kfree(context); 839 goto out; 840 } 841 /* Map ENODATA to the default file SID */ 842 sid = sbsec->def_sid; 843 rc = 0; 844 } else { 845 rc = security_context_to_sid_default(context, rc, &sid, 846 sbsec->def_sid); 847 if (rc) { 848 printk(KERN_WARNING "%s: context_to_sid(%s) " 849 "returned %d for dev=%s ino=%ld\n", 850 __FUNCTION__, context, -rc, 851 inode->i_sb->s_id, inode->i_ino); 852 kfree(context); 853 /* Leave with the unlabeled SID */ 854 rc = 0; 855 break; 856 } 857 } 858 kfree(context); 859 isec->sid = sid; 860 break; 861 case SECURITY_FS_USE_TASK: 862 isec->sid = isec->task_sid; 863 break; 864 case SECURITY_FS_USE_TRANS: 865 /* Default to the fs SID. */ 866 isec->sid = sbsec->sid; 867 868 /* Try to obtain a transition SID. */ 869 isec->sclass = inode_mode_to_security_class(inode->i_mode); 870 rc = security_transition_sid(isec->task_sid, 871 sbsec->sid, 872 isec->sclass, 873 &sid); 874 if (rc) 875 goto out; 876 isec->sid = sid; 877 break; 878 default: 879 /* Default to the fs SID. */ 880 isec->sid = sbsec->sid; 881 882 if (sbsec->proc) { 883 struct proc_inode *proci = PROC_I(inode); 884 if (proci->pde) { 885 isec->sclass = inode_mode_to_security_class(inode->i_mode); 886 rc = selinux_proc_get_sid(proci->pde, 887 isec->sclass, 888 &sid); 889 if (rc) 890 goto out; 891 isec->sid = sid; 892 } 893 } 894 break; 895 } 896 897 isec->initialized = 1; 898 899 out: 900 if (isec->sclass == SECCLASS_FILE) 901 isec->sclass = inode_mode_to_security_class(inode->i_mode); 902 903 if (hold_sem) 904 up(&isec->sem); 905 return rc; 906 } 907 908 /* Convert a Linux signal to an access vector. */ 909 static inline u32 signal_to_av(int sig) 910 { 911 u32 perm = 0; 912 913 switch (sig) { 914 case SIGCHLD: 915 /* Commonly granted from child to parent. */ 916 perm = PROCESS__SIGCHLD; 917 break; 918 case SIGKILL: 919 /* Cannot be caught or ignored */ 920 perm = PROCESS__SIGKILL; 921 break; 922 case SIGSTOP: 923 /* Cannot be caught or ignored */ 924 perm = PROCESS__SIGSTOP; 925 break; 926 default: 927 /* All other signals. */ 928 perm = PROCESS__SIGNAL; 929 break; 930 } 931 932 return perm; 933 } 934 935 /* Check permission betweeen a pair of tasks, e.g. signal checks, 936 fork check, ptrace check, etc. */ 937 static int task_has_perm(struct task_struct *tsk1, 938 struct task_struct *tsk2, 939 u32 perms) 940 { 941 struct task_security_struct *tsec1, *tsec2; 942 943 tsec1 = tsk1->security; 944 tsec2 = tsk2->security; 945 return avc_has_perm(tsec1->sid, tsec2->sid, 946 SECCLASS_PROCESS, perms, NULL); 947 } 948 949 /* Check whether a task is allowed to use a capability. */ 950 static int task_has_capability(struct task_struct *tsk, 951 int cap) 952 { 953 struct task_security_struct *tsec; 954 struct avc_audit_data ad; 955 956 tsec = tsk->security; 957 958 AVC_AUDIT_DATA_INIT(&ad,CAP); 959 ad.tsk = tsk; 960 ad.u.cap = cap; 961 962 return avc_has_perm(tsec->sid, tsec->sid, 963 SECCLASS_CAPABILITY, CAP_TO_MASK(cap), &ad); 964 } 965 966 /* Check whether a task is allowed to use a system operation. */ 967 static int task_has_system(struct task_struct *tsk, 968 u32 perms) 969 { 970 struct task_security_struct *tsec; 971 972 tsec = tsk->security; 973 974 return avc_has_perm(tsec->sid, SECINITSID_KERNEL, 975 SECCLASS_SYSTEM, perms, NULL); 976 } 977 978 /* Check whether a task has a particular permission to an inode. 979 The 'adp' parameter is optional and allows other audit 980 data to be passed (e.g. the dentry). */ 981 static int inode_has_perm(struct task_struct *tsk, 982 struct inode *inode, 983 u32 perms, 984 struct avc_audit_data *adp) 985 { 986 struct task_security_struct *tsec; 987 struct inode_security_struct *isec; 988 struct avc_audit_data ad; 989 990 tsec = tsk->security; 991 isec = inode->i_security; 992 993 if (!adp) { 994 adp = &ad; 995 AVC_AUDIT_DATA_INIT(&ad, FS); 996 ad.u.fs.inode = inode; 997 } 998 999 return avc_has_perm(tsec->sid, isec->sid, isec->sclass, perms, adp); 1000 } 1001 1002 /* Same as inode_has_perm, but pass explicit audit data containing 1003 the dentry to help the auditing code to more easily generate the 1004 pathname if needed. */ 1005 static inline int dentry_has_perm(struct task_struct *tsk, 1006 struct vfsmount *mnt, 1007 struct dentry *dentry, 1008 u32 av) 1009 { 1010 struct inode *inode = dentry->d_inode; 1011 struct avc_audit_data ad; 1012 AVC_AUDIT_DATA_INIT(&ad,FS); 1013 ad.u.fs.mnt = mnt; 1014 ad.u.fs.dentry = dentry; 1015 return inode_has_perm(tsk, inode, av, &ad); 1016 } 1017 1018 /* Check whether a task can use an open file descriptor to 1019 access an inode in a given way. Check access to the 1020 descriptor itself, and then use dentry_has_perm to 1021 check a particular permission to the file. 1022 Access to the descriptor is implicitly granted if it 1023 has the same SID as the process. If av is zero, then 1024 access to the file is not checked, e.g. for cases 1025 where only the descriptor is affected like seek. */ 1026 static inline int file_has_perm(struct task_struct *tsk, 1027 struct file *file, 1028 u32 av) 1029 { 1030 struct task_security_struct *tsec = tsk->security; 1031 struct file_security_struct *fsec = file->f_security; 1032 struct vfsmount *mnt = file->f_vfsmnt; 1033 struct dentry *dentry = file->f_dentry; 1034 struct inode *inode = dentry->d_inode; 1035 struct avc_audit_data ad; 1036 int rc; 1037 1038 AVC_AUDIT_DATA_INIT(&ad, FS); 1039 ad.u.fs.mnt = mnt; 1040 ad.u.fs.dentry = dentry; 1041 1042 if (tsec->sid != fsec->sid) { 1043 rc = avc_has_perm(tsec->sid, fsec->sid, 1044 SECCLASS_FD, 1045 FD__USE, 1046 &ad); 1047 if (rc) 1048 return rc; 1049 } 1050 1051 /* av is zero if only checking access to the descriptor. */ 1052 if (av) 1053 return inode_has_perm(tsk, inode, av, &ad); 1054 1055 return 0; 1056 } 1057 1058 /* Check whether a task can create a file. */ 1059 static int may_create(struct inode *dir, 1060 struct dentry *dentry, 1061 u16 tclass) 1062 { 1063 struct task_security_struct *tsec; 1064 struct inode_security_struct *dsec; 1065 struct superblock_security_struct *sbsec; 1066 u32 newsid; 1067 struct avc_audit_data ad; 1068 int rc; 1069 1070 tsec = current->security; 1071 dsec = dir->i_security; 1072 sbsec = dir->i_sb->s_security; 1073 1074 AVC_AUDIT_DATA_INIT(&ad, FS); 1075 ad.u.fs.dentry = dentry; 1076 1077 rc = avc_has_perm(tsec->sid, dsec->sid, SECCLASS_DIR, 1078 DIR__ADD_NAME | DIR__SEARCH, 1079 &ad); 1080 if (rc) 1081 return rc; 1082 1083 if (tsec->create_sid && sbsec->behavior != SECURITY_FS_USE_MNTPOINT) { 1084 newsid = tsec->create_sid; 1085 } else { 1086 rc = security_transition_sid(tsec->sid, dsec->sid, tclass, 1087 &newsid); 1088 if (rc) 1089 return rc; 1090 } 1091 1092 rc = avc_has_perm(tsec->sid, newsid, tclass, FILE__CREATE, &ad); 1093 if (rc) 1094 return rc; 1095 1096 return avc_has_perm(newsid, sbsec->sid, 1097 SECCLASS_FILESYSTEM, 1098 FILESYSTEM__ASSOCIATE, &ad); 1099 } 1100 1101 #define MAY_LINK 0 1102 #define MAY_UNLINK 1 1103 #define MAY_RMDIR 2 1104 1105 /* Check whether a task can link, unlink, or rmdir a file/directory. */ 1106 static int may_link(struct inode *dir, 1107 struct dentry *dentry, 1108 int kind) 1109 1110 { 1111 struct task_security_struct *tsec; 1112 struct inode_security_struct *dsec, *isec; 1113 struct avc_audit_data ad; 1114 u32 av; 1115 int rc; 1116 1117 tsec = current->security; 1118 dsec = dir->i_security; 1119 isec = dentry->d_inode->i_security; 1120 1121 AVC_AUDIT_DATA_INIT(&ad, FS); 1122 ad.u.fs.dentry = dentry; 1123 1124 av = DIR__SEARCH; 1125 av |= (kind ? DIR__REMOVE_NAME : DIR__ADD_NAME); 1126 rc = avc_has_perm(tsec->sid, dsec->sid, SECCLASS_DIR, av, &ad); 1127 if (rc) 1128 return rc; 1129 1130 switch (kind) { 1131 case MAY_LINK: 1132 av = FILE__LINK; 1133 break; 1134 case MAY_UNLINK: 1135 av = FILE__UNLINK; 1136 break; 1137 case MAY_RMDIR: 1138 av = DIR__RMDIR; 1139 break; 1140 default: 1141 printk(KERN_WARNING "may_link: unrecognized kind %d\n", kind); 1142 return 0; 1143 } 1144 1145 rc = avc_has_perm(tsec->sid, isec->sid, isec->sclass, av, &ad); 1146 return rc; 1147 } 1148 1149 static inline int may_rename(struct inode *old_dir, 1150 struct dentry *old_dentry, 1151 struct inode *new_dir, 1152 struct dentry *new_dentry) 1153 { 1154 struct task_security_struct *tsec; 1155 struct inode_security_struct *old_dsec, *new_dsec, *old_isec, *new_isec; 1156 struct avc_audit_data ad; 1157 u32 av; 1158 int old_is_dir, new_is_dir; 1159 int rc; 1160 1161 tsec = current->security; 1162 old_dsec = old_dir->i_security; 1163 old_isec = old_dentry->d_inode->i_security; 1164 old_is_dir = S_ISDIR(old_dentry->d_inode->i_mode); 1165 new_dsec = new_dir->i_security; 1166 1167 AVC_AUDIT_DATA_INIT(&ad, FS); 1168 1169 ad.u.fs.dentry = old_dentry; 1170 rc = avc_has_perm(tsec->sid, old_dsec->sid, SECCLASS_DIR, 1171 DIR__REMOVE_NAME | DIR__SEARCH, &ad); 1172 if (rc) 1173 return rc; 1174 rc = avc_has_perm(tsec->sid, old_isec->sid, 1175 old_isec->sclass, FILE__RENAME, &ad); 1176 if (rc) 1177 return rc; 1178 if (old_is_dir && new_dir != old_dir) { 1179 rc = avc_has_perm(tsec->sid, old_isec->sid, 1180 old_isec->sclass, DIR__REPARENT, &ad); 1181 if (rc) 1182 return rc; 1183 } 1184 1185 ad.u.fs.dentry = new_dentry; 1186 av = DIR__ADD_NAME | DIR__SEARCH; 1187 if (new_dentry->d_inode) 1188 av |= DIR__REMOVE_NAME; 1189 rc = avc_has_perm(tsec->sid, new_dsec->sid, SECCLASS_DIR, av, &ad); 1190 if (rc) 1191 return rc; 1192 if (new_dentry->d_inode) { 1193 new_isec = new_dentry->d_inode->i_security; 1194 new_is_dir = S_ISDIR(new_dentry->d_inode->i_mode); 1195 rc = avc_has_perm(tsec->sid, new_isec->sid, 1196 new_isec->sclass, 1197 (new_is_dir ? DIR__RMDIR : FILE__UNLINK), &ad); 1198 if (rc) 1199 return rc; 1200 } 1201 1202 return 0; 1203 } 1204 1205 /* Check whether a task can perform a filesystem operation. */ 1206 static int superblock_has_perm(struct task_struct *tsk, 1207 struct super_block *sb, 1208 u32 perms, 1209 struct avc_audit_data *ad) 1210 { 1211 struct task_security_struct *tsec; 1212 struct superblock_security_struct *sbsec; 1213 1214 tsec = tsk->security; 1215 sbsec = sb->s_security; 1216 return avc_has_perm(tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM, 1217 perms, ad); 1218 } 1219 1220 /* Convert a Linux mode and permission mask to an access vector. */ 1221 static inline u32 file_mask_to_av(int mode, int mask) 1222 { 1223 u32 av = 0; 1224 1225 if ((mode & S_IFMT) != S_IFDIR) { 1226 if (mask & MAY_EXEC) 1227 av |= FILE__EXECUTE; 1228 if (mask & MAY_READ) 1229 av |= FILE__READ; 1230 1231 if (mask & MAY_APPEND) 1232 av |= FILE__APPEND; 1233 else if (mask & MAY_WRITE) 1234 av |= FILE__WRITE; 1235 1236 } else { 1237 if (mask & MAY_EXEC) 1238 av |= DIR__SEARCH; 1239 if (mask & MAY_WRITE) 1240 av |= DIR__WRITE; 1241 if (mask & MAY_READ) 1242 av |= DIR__READ; 1243 } 1244 1245 return av; 1246 } 1247 1248 /* Convert a Linux file to an access vector. */ 1249 static inline u32 file_to_av(struct file *file) 1250 { 1251 u32 av = 0; 1252 1253 if (file->f_mode & FMODE_READ) 1254 av |= FILE__READ; 1255 if (file->f_mode & FMODE_WRITE) { 1256 if (file->f_flags & O_APPEND) 1257 av |= FILE__APPEND; 1258 else 1259 av |= FILE__WRITE; 1260 } 1261 1262 return av; 1263 } 1264 1265 /* Set an inode's SID to a specified value. */ 1266 static int inode_security_set_sid(struct inode *inode, u32 sid) 1267 { 1268 struct inode_security_struct *isec = inode->i_security; 1269 struct superblock_security_struct *sbsec = inode->i_sb->s_security; 1270 1271 if (!sbsec->initialized) { 1272 /* Defer initialization to selinux_complete_init. */ 1273 return 0; 1274 } 1275 1276 down(&isec->sem); 1277 isec->sclass = inode_mode_to_security_class(inode->i_mode); 1278 isec->sid = sid; 1279 isec->initialized = 1; 1280 up(&isec->sem); 1281 return 0; 1282 } 1283 1284 /* Hook functions begin here. */ 1285 1286 static int selinux_ptrace(struct task_struct *parent, struct task_struct *child) 1287 { 1288 struct task_security_struct *psec = parent->security; 1289 struct task_security_struct *csec = child->security; 1290 int rc; 1291 1292 rc = secondary_ops->ptrace(parent,child); 1293 if (rc) 1294 return rc; 1295 1296 rc = task_has_perm(parent, child, PROCESS__PTRACE); 1297 /* Save the SID of the tracing process for later use in apply_creds. */ 1298 if (!rc) 1299 csec->ptrace_sid = psec->sid; 1300 return rc; 1301 } 1302 1303 static int selinux_capget(struct task_struct *target, kernel_cap_t *effective, 1304 kernel_cap_t *inheritable, kernel_cap_t *permitted) 1305 { 1306 int error; 1307 1308 error = task_has_perm(current, target, PROCESS__GETCAP); 1309 if (error) 1310 return error; 1311 1312 return secondary_ops->capget(target, effective, inheritable, permitted); 1313 } 1314 1315 static int selinux_capset_check(struct task_struct *target, kernel_cap_t *effective, 1316 kernel_cap_t *inheritable, kernel_cap_t *permitted) 1317 { 1318 int error; 1319 1320 error = secondary_ops->capset_check(target, effective, inheritable, permitted); 1321 if (error) 1322 return error; 1323 1324 return task_has_perm(current, target, PROCESS__SETCAP); 1325 } 1326 1327 static void selinux_capset_set(struct task_struct *target, kernel_cap_t *effective, 1328 kernel_cap_t *inheritable, kernel_cap_t *permitted) 1329 { 1330 secondary_ops->capset_set(target, effective, inheritable, permitted); 1331 } 1332 1333 static int selinux_capable(struct task_struct *tsk, int cap) 1334 { 1335 int rc; 1336 1337 rc = secondary_ops->capable(tsk, cap); 1338 if (rc) 1339 return rc; 1340 1341 return task_has_capability(tsk,cap); 1342 } 1343 1344 static int selinux_sysctl(ctl_table *table, int op) 1345 { 1346 int error = 0; 1347 u32 av; 1348 struct task_security_struct *tsec; 1349 u32 tsid; 1350 int rc; 1351 1352 rc = secondary_ops->sysctl(table, op); 1353 if (rc) 1354 return rc; 1355 1356 tsec = current->security; 1357 1358 rc = selinux_proc_get_sid(table->de, (op == 001) ? 1359 SECCLASS_DIR : SECCLASS_FILE, &tsid); 1360 if (rc) { 1361 /* Default to the well-defined sysctl SID. */ 1362 tsid = SECINITSID_SYSCTL; 1363 } 1364 1365 /* The op values are "defined" in sysctl.c, thereby creating 1366 * a bad coupling between this module and sysctl.c */ 1367 if(op == 001) { 1368 error = avc_has_perm(tsec->sid, tsid, 1369 SECCLASS_DIR, DIR__SEARCH, NULL); 1370 } else { 1371 av = 0; 1372 if (op & 004) 1373 av |= FILE__READ; 1374 if (op & 002) 1375 av |= FILE__WRITE; 1376 if (av) 1377 error = avc_has_perm(tsec->sid, tsid, 1378 SECCLASS_FILE, av, NULL); 1379 } 1380 1381 return error; 1382 } 1383 1384 static int selinux_quotactl(int cmds, int type, int id, struct super_block *sb) 1385 { 1386 int rc = 0; 1387 1388 if (!sb) 1389 return 0; 1390 1391 switch (cmds) { 1392 case Q_SYNC: 1393 case Q_QUOTAON: 1394 case Q_QUOTAOFF: 1395 case Q_SETINFO: 1396 case Q_SETQUOTA: 1397 rc = superblock_has_perm(current, 1398 sb, 1399 FILESYSTEM__QUOTAMOD, NULL); 1400 break; 1401 case Q_GETFMT: 1402 case Q_GETINFO: 1403 case Q_GETQUOTA: 1404 rc = superblock_has_perm(current, 1405 sb, 1406 FILESYSTEM__QUOTAGET, NULL); 1407 break; 1408 default: 1409 rc = 0; /* let the kernel handle invalid cmds */ 1410 break; 1411 } 1412 return rc; 1413 } 1414 1415 static int selinux_quota_on(struct dentry *dentry) 1416 { 1417 return dentry_has_perm(current, NULL, dentry, FILE__QUOTAON); 1418 } 1419 1420 static int selinux_syslog(int type) 1421 { 1422 int rc; 1423 1424 rc = secondary_ops->syslog(type); 1425 if (rc) 1426 return rc; 1427 1428 switch (type) { 1429 case 3: /* Read last kernel messages */ 1430 case 10: /* Return size of the log buffer */ 1431 rc = task_has_system(current, SYSTEM__SYSLOG_READ); 1432 break; 1433 case 6: /* Disable logging to console */ 1434 case 7: /* Enable logging to console */ 1435 case 8: /* Set level of messages printed to console */ 1436 rc = task_has_system(current, SYSTEM__SYSLOG_CONSOLE); 1437 break; 1438 case 0: /* Close log */ 1439 case 1: /* Open log */ 1440 case 2: /* Read from log */ 1441 case 4: /* Read/clear last kernel messages */ 1442 case 5: /* Clear ring buffer */ 1443 default: 1444 rc = task_has_system(current, SYSTEM__SYSLOG_MOD); 1445 break; 1446 } 1447 return rc; 1448 } 1449 1450 /* 1451 * Check that a process has enough memory to allocate a new virtual 1452 * mapping. 0 means there is enough memory for the allocation to 1453 * succeed and -ENOMEM implies there is not. 1454 * 1455 * Note that secondary_ops->capable and task_has_perm_noaudit return 0 1456 * if the capability is granted, but __vm_enough_memory requires 1 if 1457 * the capability is granted. 1458 * 1459 * Do not audit the selinux permission check, as this is applied to all 1460 * processes that allocate mappings. 1461 */ 1462 static int selinux_vm_enough_memory(long pages) 1463 { 1464 int rc, cap_sys_admin = 0; 1465 struct task_security_struct *tsec = current->security; 1466 1467 rc = secondary_ops->capable(current, CAP_SYS_ADMIN); 1468 if (rc == 0) 1469 rc = avc_has_perm_noaudit(tsec->sid, tsec->sid, 1470 SECCLASS_CAPABILITY, 1471 CAP_TO_MASK(CAP_SYS_ADMIN), 1472 NULL); 1473 1474 if (rc == 0) 1475 cap_sys_admin = 1; 1476 1477 return __vm_enough_memory(pages, cap_sys_admin); 1478 } 1479 1480 /* binprm security operations */ 1481 1482 static int selinux_bprm_alloc_security(struct linux_binprm *bprm) 1483 { 1484 struct bprm_security_struct *bsec; 1485 1486 bsec = kmalloc(sizeof(struct bprm_security_struct), GFP_KERNEL); 1487 if (!bsec) 1488 return -ENOMEM; 1489 1490 memset(bsec, 0, sizeof *bsec); 1491 bsec->magic = SELINUX_MAGIC; 1492 bsec->bprm = bprm; 1493 bsec->sid = SECINITSID_UNLABELED; 1494 bsec->set = 0; 1495 1496 bprm->security = bsec; 1497 return 0; 1498 } 1499 1500 static int selinux_bprm_set_security(struct linux_binprm *bprm) 1501 { 1502 struct task_security_struct *tsec; 1503 struct inode *inode = bprm->file->f_dentry->d_inode; 1504 struct inode_security_struct *isec; 1505 struct bprm_security_struct *bsec; 1506 u32 newsid; 1507 struct avc_audit_data ad; 1508 int rc; 1509 1510 rc = secondary_ops->bprm_set_security(bprm); 1511 if (rc) 1512 return rc; 1513 1514 bsec = bprm->security; 1515 1516 if (bsec->set) 1517 return 0; 1518 1519 tsec = current->security; 1520 isec = inode->i_security; 1521 1522 /* Default to the current task SID. */ 1523 bsec->sid = tsec->sid; 1524 1525 /* Reset create SID on execve. */ 1526 tsec->create_sid = 0; 1527 1528 if (tsec->exec_sid) { 1529 newsid = tsec->exec_sid; 1530 /* Reset exec SID on execve. */ 1531 tsec->exec_sid = 0; 1532 } else { 1533 /* Check for a default transition on this program. */ 1534 rc = security_transition_sid(tsec->sid, isec->sid, 1535 SECCLASS_PROCESS, &newsid); 1536 if (rc) 1537 return rc; 1538 } 1539 1540 AVC_AUDIT_DATA_INIT(&ad, FS); 1541 ad.u.fs.mnt = bprm->file->f_vfsmnt; 1542 ad.u.fs.dentry = bprm->file->f_dentry; 1543 1544 if (bprm->file->f_vfsmnt->mnt_flags & MNT_NOSUID) 1545 newsid = tsec->sid; 1546 1547 if (tsec->sid == newsid) { 1548 rc = avc_has_perm(tsec->sid, isec->sid, 1549 SECCLASS_FILE, FILE__EXECUTE_NO_TRANS, &ad); 1550 if (rc) 1551 return rc; 1552 } else { 1553 /* Check permissions for the transition. */ 1554 rc = avc_has_perm(tsec->sid, newsid, 1555 SECCLASS_PROCESS, PROCESS__TRANSITION, &ad); 1556 if (rc) 1557 return rc; 1558 1559 rc = avc_has_perm(newsid, isec->sid, 1560 SECCLASS_FILE, FILE__ENTRYPOINT, &ad); 1561 if (rc) 1562 return rc; 1563 1564 /* Clear any possibly unsafe personality bits on exec: */ 1565 current->personality &= ~PER_CLEAR_ON_SETID; 1566 1567 /* Set the security field to the new SID. */ 1568 bsec->sid = newsid; 1569 } 1570 1571 bsec->set = 1; 1572 return 0; 1573 } 1574 1575 static int selinux_bprm_check_security (struct linux_binprm *bprm) 1576 { 1577 return secondary_ops->bprm_check_security(bprm); 1578 } 1579 1580 1581 static int selinux_bprm_secureexec (struct linux_binprm *bprm) 1582 { 1583 struct task_security_struct *tsec = current->security; 1584 int atsecure = 0; 1585 1586 if (tsec->osid != tsec->sid) { 1587 /* Enable secure mode for SIDs transitions unless 1588 the noatsecure permission is granted between 1589 the two SIDs, i.e. ahp returns 0. */ 1590 atsecure = avc_has_perm(tsec->osid, tsec->sid, 1591 SECCLASS_PROCESS, 1592 PROCESS__NOATSECURE, NULL); 1593 } 1594 1595 return (atsecure || secondary_ops->bprm_secureexec(bprm)); 1596 } 1597 1598 static void selinux_bprm_free_security(struct linux_binprm *bprm) 1599 { 1600 kfree(bprm->security); 1601 bprm->security = NULL; 1602 } 1603 1604 extern struct vfsmount *selinuxfs_mount; 1605 extern struct dentry *selinux_null; 1606 1607 /* Derived from fs/exec.c:flush_old_files. */ 1608 static inline void flush_unauthorized_files(struct files_struct * files) 1609 { 1610 struct avc_audit_data ad; 1611 struct file *file, *devnull = NULL; 1612 struct tty_struct *tty = current->signal->tty; 1613 struct fdtable *fdt; 1614 long j = -1; 1615 1616 if (tty) { 1617 file_list_lock(); 1618 file = list_entry(tty->tty_files.next, typeof(*file), f_list); 1619 if (file) { 1620 /* Revalidate access to controlling tty. 1621 Use inode_has_perm on the tty inode directly rather 1622 than using file_has_perm, as this particular open 1623 file may belong to another process and we are only 1624 interested in the inode-based check here. */ 1625 struct inode *inode = file->f_dentry->d_inode; 1626 if (inode_has_perm(current, inode, 1627 FILE__READ | FILE__WRITE, NULL)) { 1628 /* Reset controlling tty. */ 1629 current->signal->tty = NULL; 1630 current->signal->tty_old_pgrp = 0; 1631 } 1632 } 1633 file_list_unlock(); 1634 } 1635 1636 /* Revalidate access to inherited open files. */ 1637 1638 AVC_AUDIT_DATA_INIT(&ad,FS); 1639 1640 spin_lock(&files->file_lock); 1641 for (;;) { 1642 unsigned long set, i; 1643 int fd; 1644 1645 j++; 1646 i = j * __NFDBITS; 1647 fdt = files_fdtable(files); 1648 if (i >= fdt->max_fds || i >= fdt->max_fdset) 1649 break; 1650 set = fdt->open_fds->fds_bits[j]; 1651 if (!set) 1652 continue; 1653 spin_unlock(&files->file_lock); 1654 for ( ; set ; i++,set >>= 1) { 1655 if (set & 1) { 1656 file = fget(i); 1657 if (!file) 1658 continue; 1659 if (file_has_perm(current, 1660 file, 1661 file_to_av(file))) { 1662 sys_close(i); 1663 fd = get_unused_fd(); 1664 if (fd != i) { 1665 if (fd >= 0) 1666 put_unused_fd(fd); 1667 fput(file); 1668 continue; 1669 } 1670 if (devnull) { 1671 rcuref_inc(&devnull->f_count); 1672 } else { 1673 devnull = dentry_open(dget(selinux_null), mntget(selinuxfs_mount), O_RDWR); 1674 if (!devnull) { 1675 put_unused_fd(fd); 1676 fput(file); 1677 continue; 1678 } 1679 } 1680 fd_install(fd, devnull); 1681 } 1682 fput(file); 1683 } 1684 } 1685 spin_lock(&files->file_lock); 1686 1687 } 1688 spin_unlock(&files->file_lock); 1689 } 1690 1691 static void selinux_bprm_apply_creds(struct linux_binprm *bprm, int unsafe) 1692 { 1693 struct task_security_struct *tsec; 1694 struct bprm_security_struct *bsec; 1695 u32 sid; 1696 int rc; 1697 1698 secondary_ops->bprm_apply_creds(bprm, unsafe); 1699 1700 tsec = current->security; 1701 1702 bsec = bprm->security; 1703 sid = bsec->sid; 1704 1705 tsec->osid = tsec->sid; 1706 bsec->unsafe = 0; 1707 if (tsec->sid != sid) { 1708 /* Check for shared state. If not ok, leave SID 1709 unchanged and kill. */ 1710 if (unsafe & LSM_UNSAFE_SHARE) { 1711 rc = avc_has_perm(tsec->sid, sid, SECCLASS_PROCESS, 1712 PROCESS__SHARE, NULL); 1713 if (rc) { 1714 bsec->unsafe = 1; 1715 return; 1716 } 1717 } 1718 1719 /* Check for ptracing, and update the task SID if ok. 1720 Otherwise, leave SID unchanged and kill. */ 1721 if (unsafe & (LSM_UNSAFE_PTRACE | LSM_UNSAFE_PTRACE_CAP)) { 1722 rc = avc_has_perm(tsec->ptrace_sid, sid, 1723 SECCLASS_PROCESS, PROCESS__PTRACE, 1724 NULL); 1725 if (rc) { 1726 bsec->unsafe = 1; 1727 return; 1728 } 1729 } 1730 tsec->sid = sid; 1731 } 1732 } 1733 1734 /* 1735 * called after apply_creds without the task lock held 1736 */ 1737 static void selinux_bprm_post_apply_creds(struct linux_binprm *bprm) 1738 { 1739 struct task_security_struct *tsec; 1740 struct rlimit *rlim, *initrlim; 1741 struct itimerval itimer; 1742 struct bprm_security_struct *bsec; 1743 int rc, i; 1744 1745 tsec = current->security; 1746 bsec = bprm->security; 1747 1748 if (bsec->unsafe) { 1749 force_sig_specific(SIGKILL, current); 1750 return; 1751 } 1752 if (tsec->osid == tsec->sid) 1753 return; 1754 1755 /* Close files for which the new task SID is not authorized. */ 1756 flush_unauthorized_files(current->files); 1757 1758 /* Check whether the new SID can inherit signal state 1759 from the old SID. If not, clear itimers to avoid 1760 subsequent signal generation and flush and unblock 1761 signals. This must occur _after_ the task SID has 1762 been updated so that any kill done after the flush 1763 will be checked against the new SID. */ 1764 rc = avc_has_perm(tsec->osid, tsec->sid, SECCLASS_PROCESS, 1765 PROCESS__SIGINH, NULL); 1766 if (rc) { 1767 memset(&itimer, 0, sizeof itimer); 1768 for (i = 0; i < 3; i++) 1769 do_setitimer(i, &itimer, NULL); 1770 flush_signals(current); 1771 spin_lock_irq(¤t->sighand->siglock); 1772 flush_signal_handlers(current, 1); 1773 sigemptyset(¤t->blocked); 1774 recalc_sigpending(); 1775 spin_unlock_irq(¤t->sighand->siglock); 1776 } 1777 1778 /* Check whether the new SID can inherit resource limits 1779 from the old SID. If not, reset all soft limits to 1780 the lower of the current task's hard limit and the init 1781 task's soft limit. Note that the setting of hard limits 1782 (even to lower them) can be controlled by the setrlimit 1783 check. The inclusion of the init task's soft limit into 1784 the computation is to avoid resetting soft limits higher 1785 than the default soft limit for cases where the default 1786 is lower than the hard limit, e.g. RLIMIT_CORE or 1787 RLIMIT_STACK.*/ 1788 rc = avc_has_perm(tsec->osid, tsec->sid, SECCLASS_PROCESS, 1789 PROCESS__RLIMITINH, NULL); 1790 if (rc) { 1791 for (i = 0; i < RLIM_NLIMITS; i++) { 1792 rlim = current->signal->rlim + i; 1793 initrlim = init_task.signal->rlim+i; 1794 rlim->rlim_cur = min(rlim->rlim_max,initrlim->rlim_cur); 1795 } 1796 if (current->signal->rlim[RLIMIT_CPU].rlim_cur != RLIM_INFINITY) { 1797 /* 1798 * This will cause RLIMIT_CPU calculations 1799 * to be refigured. 1800 */ 1801 current->it_prof_expires = jiffies_to_cputime(1); 1802 } 1803 } 1804 1805 /* Wake up the parent if it is waiting so that it can 1806 recheck wait permission to the new task SID. */ 1807 wake_up_interruptible(¤t->parent->signal->wait_chldexit); 1808 } 1809 1810 /* superblock security operations */ 1811 1812 static int selinux_sb_alloc_security(struct super_block *sb) 1813 { 1814 return superblock_alloc_security(sb); 1815 } 1816 1817 static void selinux_sb_free_security(struct super_block *sb) 1818 { 1819 superblock_free_security(sb); 1820 } 1821 1822 static inline int match_prefix(char *prefix, int plen, char *option, int olen) 1823 { 1824 if (plen > olen) 1825 return 0; 1826 1827 return !memcmp(prefix, option, plen); 1828 } 1829 1830 static inline int selinux_option(char *option, int len) 1831 { 1832 return (match_prefix("context=", sizeof("context=")-1, option, len) || 1833 match_prefix("fscontext=", sizeof("fscontext=")-1, option, len) || 1834 match_prefix("defcontext=", sizeof("defcontext=")-1, option, len)); 1835 } 1836 1837 static inline void take_option(char **to, char *from, int *first, int len) 1838 { 1839 if (!*first) { 1840 **to = ','; 1841 *to += 1; 1842 } 1843 else 1844 *first = 0; 1845 memcpy(*to, from, len); 1846 *to += len; 1847 } 1848 1849 static int selinux_sb_copy_data(struct file_system_type *type, void *orig, void *copy) 1850 { 1851 int fnosec, fsec, rc = 0; 1852 char *in_save, *in_curr, *in_end; 1853 char *sec_curr, *nosec_save, *nosec; 1854 1855 in_curr = orig; 1856 sec_curr = copy; 1857 1858 /* Binary mount data: just copy */ 1859 if (type->fs_flags & FS_BINARY_MOUNTDATA) { 1860 copy_page(sec_curr, in_curr); 1861 goto out; 1862 } 1863 1864 nosec = (char *)get_zeroed_page(GFP_KERNEL); 1865 if (!nosec) { 1866 rc = -ENOMEM; 1867 goto out; 1868 } 1869 1870 nosec_save = nosec; 1871 fnosec = fsec = 1; 1872 in_save = in_end = orig; 1873 1874 do { 1875 if (*in_end == ',' || *in_end == '\0') { 1876 int len = in_end - in_curr; 1877 1878 if (selinux_option(in_curr, len)) 1879 take_option(&sec_curr, in_curr, &fsec, len); 1880 else 1881 take_option(&nosec, in_curr, &fnosec, len); 1882 1883 in_curr = in_end + 1; 1884 } 1885 } while (*in_end++); 1886 1887 strcpy(in_save, nosec_save); 1888 free_page((unsigned long)nosec_save); 1889 out: 1890 return rc; 1891 } 1892 1893 static int selinux_sb_kern_mount(struct super_block *sb, void *data) 1894 { 1895 struct avc_audit_data ad; 1896 int rc; 1897 1898 rc = superblock_doinit(sb, data); 1899 if (rc) 1900 return rc; 1901 1902 AVC_AUDIT_DATA_INIT(&ad,FS); 1903 ad.u.fs.dentry = sb->s_root; 1904 return superblock_has_perm(current, sb, FILESYSTEM__MOUNT, &ad); 1905 } 1906 1907 static int selinux_sb_statfs(struct super_block *sb) 1908 { 1909 struct avc_audit_data ad; 1910 1911 AVC_AUDIT_DATA_INIT(&ad,FS); 1912 ad.u.fs.dentry = sb->s_root; 1913 return superblock_has_perm(current, sb, FILESYSTEM__GETATTR, &ad); 1914 } 1915 1916 static int selinux_mount(char * dev_name, 1917 struct nameidata *nd, 1918 char * type, 1919 unsigned long flags, 1920 void * data) 1921 { 1922 int rc; 1923 1924 rc = secondary_ops->sb_mount(dev_name, nd, type, flags, data); 1925 if (rc) 1926 return rc; 1927 1928 if (flags & MS_REMOUNT) 1929 return superblock_has_perm(current, nd->mnt->mnt_sb, 1930 FILESYSTEM__REMOUNT, NULL); 1931 else 1932 return dentry_has_perm(current, nd->mnt, nd->dentry, 1933 FILE__MOUNTON); 1934 } 1935 1936 static int selinux_umount(struct vfsmount *mnt, int flags) 1937 { 1938 int rc; 1939 1940 rc = secondary_ops->sb_umount(mnt, flags); 1941 if (rc) 1942 return rc; 1943 1944 return superblock_has_perm(current,mnt->mnt_sb, 1945 FILESYSTEM__UNMOUNT,NULL); 1946 } 1947 1948 /* inode security operations */ 1949 1950 static int selinux_inode_alloc_security(struct inode *inode) 1951 { 1952 return inode_alloc_security(inode); 1953 } 1954 1955 static void selinux_inode_free_security(struct inode *inode) 1956 { 1957 inode_free_security(inode); 1958 } 1959 1960 static int selinux_inode_init_security(struct inode *inode, struct inode *dir, 1961 char **name, void **value, 1962 size_t *len) 1963 { 1964 struct task_security_struct *tsec; 1965 struct inode_security_struct *dsec; 1966 struct superblock_security_struct *sbsec; 1967 struct inode_security_struct *isec; 1968 u32 newsid, clen; 1969 int rc; 1970 char *namep = NULL, *context; 1971 1972 tsec = current->security; 1973 dsec = dir->i_security; 1974 sbsec = dir->i_sb->s_security; 1975 isec = inode->i_security; 1976 1977 if (tsec->create_sid && sbsec->behavior != SECURITY_FS_USE_MNTPOINT) { 1978 newsid = tsec->create_sid; 1979 } else { 1980 rc = security_transition_sid(tsec->sid, dsec->sid, 1981 inode_mode_to_security_class(inode->i_mode), 1982 &newsid); 1983 if (rc) { 1984 printk(KERN_WARNING "%s: " 1985 "security_transition_sid failed, rc=%d (dev=%s " 1986 "ino=%ld)\n", 1987 __FUNCTION__, 1988 -rc, inode->i_sb->s_id, inode->i_ino); 1989 return rc; 1990 } 1991 } 1992 1993 inode_security_set_sid(inode, newsid); 1994 1995 if (name) { 1996 namep = kstrdup(XATTR_SELINUX_SUFFIX, GFP_KERNEL); 1997 if (!namep) 1998 return -ENOMEM; 1999 *name = namep; 2000 } 2001 2002 if (value && len) { 2003 rc = security_sid_to_context(newsid, &context, &clen); 2004 if (rc) { 2005 kfree(namep); 2006 return rc; 2007 } 2008 *value = context; 2009 *len = clen; 2010 } 2011 2012 return 0; 2013 } 2014 2015 static int selinux_inode_create(struct inode *dir, struct dentry *dentry, int mask) 2016 { 2017 return may_create(dir, dentry, SECCLASS_FILE); 2018 } 2019 2020 static int selinux_inode_link(struct dentry *old_dentry, struct inode *dir, struct dentry *new_dentry) 2021 { 2022 int rc; 2023 2024 rc = secondary_ops->inode_link(old_dentry,dir,new_dentry); 2025 if (rc) 2026 return rc; 2027 return may_link(dir, old_dentry, MAY_LINK); 2028 } 2029 2030 static int selinux_inode_unlink(struct inode *dir, struct dentry *dentry) 2031 { 2032 int rc; 2033 2034 rc = secondary_ops->inode_unlink(dir, dentry); 2035 if (rc) 2036 return rc; 2037 return may_link(dir, dentry, MAY_UNLINK); 2038 } 2039 2040 static int selinux_inode_symlink(struct inode *dir, struct dentry *dentry, const char *name) 2041 { 2042 return may_create(dir, dentry, SECCLASS_LNK_FILE); 2043 } 2044 2045 static int selinux_inode_mkdir(struct inode *dir, struct dentry *dentry, int mask) 2046 { 2047 return may_create(dir, dentry, SECCLASS_DIR); 2048 } 2049 2050 static int selinux_inode_rmdir(struct inode *dir, struct dentry *dentry) 2051 { 2052 return may_link(dir, dentry, MAY_RMDIR); 2053 } 2054 2055 static int selinux_inode_mknod(struct inode *dir, struct dentry *dentry, int mode, dev_t dev) 2056 { 2057 int rc; 2058 2059 rc = secondary_ops->inode_mknod(dir, dentry, mode, dev); 2060 if (rc) 2061 return rc; 2062 2063 return may_create(dir, dentry, inode_mode_to_security_class(mode)); 2064 } 2065 2066 static int selinux_inode_rename(struct inode *old_inode, struct dentry *old_dentry, 2067 struct inode *new_inode, struct dentry *new_dentry) 2068 { 2069 return may_rename(old_inode, old_dentry, new_inode, new_dentry); 2070 } 2071 2072 static int selinux_inode_readlink(struct dentry *dentry) 2073 { 2074 return dentry_has_perm(current, NULL, dentry, FILE__READ); 2075 } 2076 2077 static int selinux_inode_follow_link(struct dentry *dentry, struct nameidata *nameidata) 2078 { 2079 int rc; 2080 2081 rc = secondary_ops->inode_follow_link(dentry,nameidata); 2082 if (rc) 2083 return rc; 2084 return dentry_has_perm(current, NULL, dentry, FILE__READ); 2085 } 2086 2087 static int selinux_inode_permission(struct inode *inode, int mask, 2088 struct nameidata *nd) 2089 { 2090 int rc; 2091 2092 rc = secondary_ops->inode_permission(inode, mask, nd); 2093 if (rc) 2094 return rc; 2095 2096 if (!mask) { 2097 /* No permission to check. Existence test. */ 2098 return 0; 2099 } 2100 2101 return inode_has_perm(current, inode, 2102 file_mask_to_av(inode->i_mode, mask), NULL); 2103 } 2104 2105 static int selinux_inode_setattr(struct dentry *dentry, struct iattr *iattr) 2106 { 2107 int rc; 2108 2109 rc = secondary_ops->inode_setattr(dentry, iattr); 2110 if (rc) 2111 return rc; 2112 2113 if (iattr->ia_valid & ATTR_FORCE) 2114 return 0; 2115 2116 if (iattr->ia_valid & (ATTR_MODE | ATTR_UID | ATTR_GID | 2117 ATTR_ATIME_SET | ATTR_MTIME_SET)) 2118 return dentry_has_perm(current, NULL, dentry, FILE__SETATTR); 2119 2120 return dentry_has_perm(current, NULL, dentry, FILE__WRITE); 2121 } 2122 2123 static int selinux_inode_getattr(struct vfsmount *mnt, struct dentry *dentry) 2124 { 2125 return dentry_has_perm(current, mnt, dentry, FILE__GETATTR); 2126 } 2127 2128 static int selinux_inode_setxattr(struct dentry *dentry, char *name, void *value, size_t size, int flags) 2129 { 2130 struct task_security_struct *tsec = current->security; 2131 struct inode *inode = dentry->d_inode; 2132 struct inode_security_struct *isec = inode->i_security; 2133 struct superblock_security_struct *sbsec; 2134 struct avc_audit_data ad; 2135 u32 newsid; 2136 int rc = 0; 2137 2138 if (strcmp(name, XATTR_NAME_SELINUX)) { 2139 if (!strncmp(name, XATTR_SECURITY_PREFIX, 2140 sizeof XATTR_SECURITY_PREFIX - 1) && 2141 !capable(CAP_SYS_ADMIN)) { 2142 /* A different attribute in the security namespace. 2143 Restrict to administrator. */ 2144 return -EPERM; 2145 } 2146 2147 /* Not an attribute we recognize, so just check the 2148 ordinary setattr permission. */ 2149 return dentry_has_perm(current, NULL, dentry, FILE__SETATTR); 2150 } 2151 2152 sbsec = inode->i_sb->s_security; 2153 if (sbsec->behavior == SECURITY_FS_USE_MNTPOINT) 2154 return -EOPNOTSUPP; 2155 2156 if ((current->fsuid != inode->i_uid) && !capable(CAP_FOWNER)) 2157 return -EPERM; 2158 2159 AVC_AUDIT_DATA_INIT(&ad,FS); 2160 ad.u.fs.dentry = dentry; 2161 2162 rc = avc_has_perm(tsec->sid, isec->sid, isec->sclass, 2163 FILE__RELABELFROM, &ad); 2164 if (rc) 2165 return rc; 2166 2167 rc = security_context_to_sid(value, size, &newsid); 2168 if (rc) 2169 return rc; 2170 2171 rc = avc_has_perm(tsec->sid, newsid, isec->sclass, 2172 FILE__RELABELTO, &ad); 2173 if (rc) 2174 return rc; 2175 2176 rc = security_validate_transition(isec->sid, newsid, tsec->sid, 2177 isec->sclass); 2178 if (rc) 2179 return rc; 2180 2181 return avc_has_perm(newsid, 2182 sbsec->sid, 2183 SECCLASS_FILESYSTEM, 2184 FILESYSTEM__ASSOCIATE, 2185 &ad); 2186 } 2187 2188 static void selinux_inode_post_setxattr(struct dentry *dentry, char *name, 2189 void *value, size_t size, int flags) 2190 { 2191 struct inode *inode = dentry->d_inode; 2192 struct inode_security_struct *isec = inode->i_security; 2193 u32 newsid; 2194 int rc; 2195 2196 if (strcmp(name, XATTR_NAME_SELINUX)) { 2197 /* Not an attribute we recognize, so nothing to do. */ 2198 return; 2199 } 2200 2201 rc = security_context_to_sid(value, size, &newsid); 2202 if (rc) { 2203 printk(KERN_WARNING "%s: unable to obtain SID for context " 2204 "%s, rc=%d\n", __FUNCTION__, (char*)value, -rc); 2205 return; 2206 } 2207 2208 isec->sid = newsid; 2209 return; 2210 } 2211 2212 static int selinux_inode_getxattr (struct dentry *dentry, char *name) 2213 { 2214 struct inode *inode = dentry->d_inode; 2215 struct superblock_security_struct *sbsec = inode->i_sb->s_security; 2216 2217 if (sbsec->behavior == SECURITY_FS_USE_MNTPOINT) 2218 return -EOPNOTSUPP; 2219 2220 return dentry_has_perm(current, NULL, dentry, FILE__GETATTR); 2221 } 2222 2223 static int selinux_inode_listxattr (struct dentry *dentry) 2224 { 2225 return dentry_has_perm(current, NULL, dentry, FILE__GETATTR); 2226 } 2227 2228 static int selinux_inode_removexattr (struct dentry *dentry, char *name) 2229 { 2230 if (strcmp(name, XATTR_NAME_SELINUX)) { 2231 if (!strncmp(name, XATTR_SECURITY_PREFIX, 2232 sizeof XATTR_SECURITY_PREFIX - 1) && 2233 !capable(CAP_SYS_ADMIN)) { 2234 /* A different attribute in the security namespace. 2235 Restrict to administrator. */ 2236 return -EPERM; 2237 } 2238 2239 /* Not an attribute we recognize, so just check the 2240 ordinary setattr permission. Might want a separate 2241 permission for removexattr. */ 2242 return dentry_has_perm(current, NULL, dentry, FILE__SETATTR); 2243 } 2244 2245 /* No one is allowed to remove a SELinux security label. 2246 You can change the label, but all data must be labeled. */ 2247 return -EACCES; 2248 } 2249 2250 static int selinux_inode_getsecurity(struct inode *inode, const char *name, void *buffer, size_t size) 2251 { 2252 struct inode_security_struct *isec = inode->i_security; 2253 char *context; 2254 unsigned len; 2255 int rc; 2256 2257 /* Permission check handled by selinux_inode_getxattr hook.*/ 2258 2259 if (strcmp(name, XATTR_SELINUX_SUFFIX)) 2260 return -EOPNOTSUPP; 2261 2262 rc = security_sid_to_context(isec->sid, &context, &len); 2263 if (rc) 2264 return rc; 2265 2266 if (!buffer || !size) { 2267 kfree(context); 2268 return len; 2269 } 2270 if (size < len) { 2271 kfree(context); 2272 return -ERANGE; 2273 } 2274 memcpy(buffer, context, len); 2275 kfree(context); 2276 return len; 2277 } 2278 2279 static int selinux_inode_setsecurity(struct inode *inode, const char *name, 2280 const void *value, size_t size, int flags) 2281 { 2282 struct inode_security_struct *isec = inode->i_security; 2283 u32 newsid; 2284 int rc; 2285 2286 if (strcmp(name, XATTR_SELINUX_SUFFIX)) 2287 return -EOPNOTSUPP; 2288 2289 if (!value || !size) 2290 return -EACCES; 2291 2292 rc = security_context_to_sid((void*)value, size, &newsid); 2293 if (rc) 2294 return rc; 2295 2296 isec->sid = newsid; 2297 return 0; 2298 } 2299 2300 static int selinux_inode_listsecurity(struct inode *inode, char *buffer, size_t buffer_size) 2301 { 2302 const int len = sizeof(XATTR_NAME_SELINUX); 2303 if (buffer && len <= buffer_size) 2304 memcpy(buffer, XATTR_NAME_SELINUX, len); 2305 return len; 2306 } 2307 2308 /* file security operations */ 2309 2310 static int selinux_file_permission(struct file *file, int mask) 2311 { 2312 struct inode *inode = file->f_dentry->d_inode; 2313 2314 if (!mask) { 2315 /* No permission to check. Existence test. */ 2316 return 0; 2317 } 2318 2319 /* file_mask_to_av won't add FILE__WRITE if MAY_APPEND is set */ 2320 if ((file->f_flags & O_APPEND) && (mask & MAY_WRITE)) 2321 mask |= MAY_APPEND; 2322 2323 return file_has_perm(current, file, 2324 file_mask_to_av(inode->i_mode, mask)); 2325 } 2326 2327 static int selinux_file_alloc_security(struct file *file) 2328 { 2329 return file_alloc_security(file); 2330 } 2331 2332 static void selinux_file_free_security(struct file *file) 2333 { 2334 file_free_security(file); 2335 } 2336 2337 static int selinux_file_ioctl(struct file *file, unsigned int cmd, 2338 unsigned long arg) 2339 { 2340 int error = 0; 2341 2342 switch (cmd) { 2343 case FIONREAD: 2344 /* fall through */ 2345 case FIBMAP: 2346 /* fall through */ 2347 case FIGETBSZ: 2348 /* fall through */ 2349 case EXT2_IOC_GETFLAGS: 2350 /* fall through */ 2351 case EXT2_IOC_GETVERSION: 2352 error = file_has_perm(current, file, FILE__GETATTR); 2353 break; 2354 2355 case EXT2_IOC_SETFLAGS: 2356 /* fall through */ 2357 case EXT2_IOC_SETVERSION: 2358 error = file_has_perm(current, file, FILE__SETATTR); 2359 break; 2360 2361 /* sys_ioctl() checks */ 2362 case FIONBIO: 2363 /* fall through */ 2364 case FIOASYNC: 2365 error = file_has_perm(current, file, 0); 2366 break; 2367 2368 case KDSKBENT: 2369 case KDSKBSENT: 2370 error = task_has_capability(current,CAP_SYS_TTY_CONFIG); 2371 break; 2372 2373 /* default case assumes that the command will go 2374 * to the file's ioctl() function. 2375 */ 2376 default: 2377 error = file_has_perm(current, file, FILE__IOCTL); 2378 2379 } 2380 return error; 2381 } 2382 2383 static int file_map_prot_check(struct file *file, unsigned long prot, int shared) 2384 { 2385 #ifndef CONFIG_PPC32 2386 if ((prot & PROT_EXEC) && (!file || (!shared && (prot & PROT_WRITE)))) { 2387 /* 2388 * We are making executable an anonymous mapping or a 2389 * private file mapping that will also be writable. 2390 * This has an additional check. 2391 */ 2392 int rc = task_has_perm(current, current, PROCESS__EXECMEM); 2393 if (rc) 2394 return rc; 2395 } 2396 #endif 2397 2398 if (file) { 2399 /* read access is always possible with a mapping */ 2400 u32 av = FILE__READ; 2401 2402 /* write access only matters if the mapping is shared */ 2403 if (shared && (prot & PROT_WRITE)) 2404 av |= FILE__WRITE; 2405 2406 if (prot & PROT_EXEC) 2407 av |= FILE__EXECUTE; 2408 2409 return file_has_perm(current, file, av); 2410 } 2411 return 0; 2412 } 2413 2414 static int selinux_file_mmap(struct file *file, unsigned long reqprot, 2415 unsigned long prot, unsigned long flags) 2416 { 2417 int rc; 2418 2419 rc = secondary_ops->file_mmap(file, reqprot, prot, flags); 2420 if (rc) 2421 return rc; 2422 2423 if (selinux_checkreqprot) 2424 prot = reqprot; 2425 2426 return file_map_prot_check(file, prot, 2427 (flags & MAP_TYPE) == MAP_SHARED); 2428 } 2429 2430 static int selinux_file_mprotect(struct vm_area_struct *vma, 2431 unsigned long reqprot, 2432 unsigned long prot) 2433 { 2434 int rc; 2435 2436 rc = secondary_ops->file_mprotect(vma, reqprot, prot); 2437 if (rc) 2438 return rc; 2439 2440 if (selinux_checkreqprot) 2441 prot = reqprot; 2442 2443 #ifndef CONFIG_PPC32 2444 if ((prot & PROT_EXEC) && !(vma->vm_flags & VM_EXECUTABLE) && 2445 (vma->vm_start >= vma->vm_mm->start_brk && 2446 vma->vm_end <= vma->vm_mm->brk)) { 2447 /* 2448 * We are making an executable mapping in the brk region. 2449 * This has an additional execheap check. 2450 */ 2451 rc = task_has_perm(current, current, PROCESS__EXECHEAP); 2452 if (rc) 2453 return rc; 2454 } 2455 if (vma->vm_file != NULL && vma->anon_vma != NULL && (prot & PROT_EXEC)) { 2456 /* 2457 * We are making executable a file mapping that has 2458 * had some COW done. Since pages might have been written, 2459 * check ability to execute the possibly modified content. 2460 * This typically should only occur for text relocations. 2461 */ 2462 int rc = file_has_perm(current, vma->vm_file, FILE__EXECMOD); 2463 if (rc) 2464 return rc; 2465 } 2466 if (!vma->vm_file && (prot & PROT_EXEC) && 2467 vma->vm_start <= vma->vm_mm->start_stack && 2468 vma->vm_end >= vma->vm_mm->start_stack) { 2469 /* Attempt to make the process stack executable. 2470 * This has an additional execstack check. 2471 */ 2472 rc = task_has_perm(current, current, PROCESS__EXECSTACK); 2473 if (rc) 2474 return rc; 2475 } 2476 #endif 2477 2478 return file_map_prot_check(vma->vm_file, prot, vma->vm_flags&VM_SHARED); 2479 } 2480 2481 static int selinux_file_lock(struct file *file, unsigned int cmd) 2482 { 2483 return file_has_perm(current, file, FILE__LOCK); 2484 } 2485 2486 static int selinux_file_fcntl(struct file *file, unsigned int cmd, 2487 unsigned long arg) 2488 { 2489 int err = 0; 2490 2491 switch (cmd) { 2492 case F_SETFL: 2493 if (!file->f_dentry || !file->f_dentry->d_inode) { 2494 err = -EINVAL; 2495 break; 2496 } 2497 2498 if ((file->f_flags & O_APPEND) && !(arg & O_APPEND)) { 2499 err = file_has_perm(current, file,FILE__WRITE); 2500 break; 2501 } 2502 /* fall through */ 2503 case F_SETOWN: 2504 case F_SETSIG: 2505 case F_GETFL: 2506 case F_GETOWN: 2507 case F_GETSIG: 2508 /* Just check FD__USE permission */ 2509 err = file_has_perm(current, file, 0); 2510 break; 2511 case F_GETLK: 2512 case F_SETLK: 2513 case F_SETLKW: 2514 #if BITS_PER_LONG == 32 2515 case F_GETLK64: 2516 case F_SETLK64: 2517 case F_SETLKW64: 2518 #endif 2519 if (!file->f_dentry || !file->f_dentry->d_inode) { 2520 err = -EINVAL; 2521 break; 2522 } 2523 err = file_has_perm(current, file, FILE__LOCK); 2524 break; 2525 } 2526 2527 return err; 2528 } 2529 2530 static int selinux_file_set_fowner(struct file *file) 2531 { 2532 struct task_security_struct *tsec; 2533 struct file_security_struct *fsec; 2534 2535 tsec = current->security; 2536 fsec = file->f_security; 2537 fsec->fown_sid = tsec->sid; 2538 2539 return 0; 2540 } 2541 2542 static int selinux_file_send_sigiotask(struct task_struct *tsk, 2543 struct fown_struct *fown, int signum) 2544 { 2545 struct file *file; 2546 u32 perm; 2547 struct task_security_struct *tsec; 2548 struct file_security_struct *fsec; 2549 2550 /* struct fown_struct is never outside the context of a struct file */ 2551 file = (struct file *)((long)fown - offsetof(struct file,f_owner)); 2552 2553 tsec = tsk->security; 2554 fsec = file->f_security; 2555 2556 if (!signum) 2557 perm = signal_to_av(SIGIO); /* as per send_sigio_to_task */ 2558 else 2559 perm = signal_to_av(signum); 2560 2561 return avc_has_perm(fsec->fown_sid, tsec->sid, 2562 SECCLASS_PROCESS, perm, NULL); 2563 } 2564 2565 static int selinux_file_receive(struct file *file) 2566 { 2567 return file_has_perm(current, file, file_to_av(file)); 2568 } 2569 2570 /* task security operations */ 2571 2572 static int selinux_task_create(unsigned long clone_flags) 2573 { 2574 int rc; 2575 2576 rc = secondary_ops->task_create(clone_flags); 2577 if (rc) 2578 return rc; 2579 2580 return task_has_perm(current, current, PROCESS__FORK); 2581 } 2582 2583 static int selinux_task_alloc_security(struct task_struct *tsk) 2584 { 2585 struct task_security_struct *tsec1, *tsec2; 2586 int rc; 2587 2588 tsec1 = current->security; 2589 2590 rc = task_alloc_security(tsk); 2591 if (rc) 2592 return rc; 2593 tsec2 = tsk->security; 2594 2595 tsec2->osid = tsec1->osid; 2596 tsec2->sid = tsec1->sid; 2597 2598 /* Retain the exec and create SIDs across fork */ 2599 tsec2->exec_sid = tsec1->exec_sid; 2600 tsec2->create_sid = tsec1->create_sid; 2601 2602 /* Retain ptracer SID across fork, if any. 2603 This will be reset by the ptrace hook upon any 2604 subsequent ptrace_attach operations. */ 2605 tsec2->ptrace_sid = tsec1->ptrace_sid; 2606 2607 return 0; 2608 } 2609 2610 static void selinux_task_free_security(struct task_struct *tsk) 2611 { 2612 task_free_security(tsk); 2613 } 2614 2615 static int selinux_task_setuid(uid_t id0, uid_t id1, uid_t id2, int flags) 2616 { 2617 /* Since setuid only affects the current process, and 2618 since the SELinux controls are not based on the Linux 2619 identity attributes, SELinux does not need to control 2620 this operation. However, SELinux does control the use 2621 of the CAP_SETUID and CAP_SETGID capabilities using the 2622 capable hook. */ 2623 return 0; 2624 } 2625 2626 static int selinux_task_post_setuid(uid_t id0, uid_t id1, uid_t id2, int flags) 2627 { 2628 return secondary_ops->task_post_setuid(id0,id1,id2,flags); 2629 } 2630 2631 static int selinux_task_setgid(gid_t id0, gid_t id1, gid_t id2, int flags) 2632 { 2633 /* See the comment for setuid above. */ 2634 return 0; 2635 } 2636 2637 static int selinux_task_setpgid(struct task_struct *p, pid_t pgid) 2638 { 2639 return task_has_perm(current, p, PROCESS__SETPGID); 2640 } 2641 2642 static int selinux_task_getpgid(struct task_struct *p) 2643 { 2644 return task_has_perm(current, p, PROCESS__GETPGID); 2645 } 2646 2647 static int selinux_task_getsid(struct task_struct *p) 2648 { 2649 return task_has_perm(current, p, PROCESS__GETSESSION); 2650 } 2651 2652 static int selinux_task_setgroups(struct group_info *group_info) 2653 { 2654 /* See the comment for setuid above. */ 2655 return 0; 2656 } 2657 2658 static int selinux_task_setnice(struct task_struct *p, int nice) 2659 { 2660 int rc; 2661 2662 rc = secondary_ops->task_setnice(p, nice); 2663 if (rc) 2664 return rc; 2665 2666 return task_has_perm(current,p, PROCESS__SETSCHED); 2667 } 2668 2669 static int selinux_task_setrlimit(unsigned int resource, struct rlimit *new_rlim) 2670 { 2671 struct rlimit *old_rlim = current->signal->rlim + resource; 2672 int rc; 2673 2674 rc = secondary_ops->task_setrlimit(resource, new_rlim); 2675 if (rc) 2676 return rc; 2677 2678 /* Control the ability to change the hard limit (whether 2679 lowering or raising it), so that the hard limit can 2680 later be used as a safe reset point for the soft limit 2681 upon context transitions. See selinux_bprm_apply_creds. */ 2682 if (old_rlim->rlim_max != new_rlim->rlim_max) 2683 return task_has_perm(current, current, PROCESS__SETRLIMIT); 2684 2685 return 0; 2686 } 2687 2688 static int selinux_task_setscheduler(struct task_struct *p, int policy, struct sched_param *lp) 2689 { 2690 return task_has_perm(current, p, PROCESS__SETSCHED); 2691 } 2692 2693 static int selinux_task_getscheduler(struct task_struct *p) 2694 { 2695 return task_has_perm(current, p, PROCESS__GETSCHED); 2696 } 2697 2698 static int selinux_task_kill(struct task_struct *p, struct siginfo *info, int sig) 2699 { 2700 u32 perm; 2701 int rc; 2702 2703 rc = secondary_ops->task_kill(p, info, sig); 2704 if (rc) 2705 return rc; 2706 2707 if (info && ((unsigned long)info == 1 || 2708 (unsigned long)info == 2 || SI_FROMKERNEL(info))) 2709 return 0; 2710 2711 if (!sig) 2712 perm = PROCESS__SIGNULL; /* null signal; existence test */ 2713 else 2714 perm = signal_to_av(sig); 2715 2716 return task_has_perm(current, p, perm); 2717 } 2718 2719 static int selinux_task_prctl(int option, 2720 unsigned long arg2, 2721 unsigned long arg3, 2722 unsigned long arg4, 2723 unsigned long arg5) 2724 { 2725 /* The current prctl operations do not appear to require 2726 any SELinux controls since they merely observe or modify 2727 the state of the current process. */ 2728 return 0; 2729 } 2730 2731 static int selinux_task_wait(struct task_struct *p) 2732 { 2733 u32 perm; 2734 2735 perm = signal_to_av(p->exit_signal); 2736 2737 return task_has_perm(p, current, perm); 2738 } 2739 2740 static void selinux_task_reparent_to_init(struct task_struct *p) 2741 { 2742 struct task_security_struct *tsec; 2743 2744 secondary_ops->task_reparent_to_init(p); 2745 2746 tsec = p->security; 2747 tsec->osid = tsec->sid; 2748 tsec->sid = SECINITSID_KERNEL; 2749 return; 2750 } 2751 2752 static void selinux_task_to_inode(struct task_struct *p, 2753 struct inode *inode) 2754 { 2755 struct task_security_struct *tsec = p->security; 2756 struct inode_security_struct *isec = inode->i_security; 2757 2758 isec->sid = tsec->sid; 2759 isec->initialized = 1; 2760 return; 2761 } 2762 2763 #ifdef CONFIG_SECURITY_NETWORK 2764 2765 /* Returns error only if unable to parse addresses */ 2766 static int selinux_parse_skb_ipv4(struct sk_buff *skb, struct avc_audit_data *ad) 2767 { 2768 int offset, ihlen, ret = -EINVAL; 2769 struct iphdr _iph, *ih; 2770 2771 offset = skb->nh.raw - skb->data; 2772 ih = skb_header_pointer(skb, offset, sizeof(_iph), &_iph); 2773 if (ih == NULL) 2774 goto out; 2775 2776 ihlen = ih->ihl * 4; 2777 if (ihlen < sizeof(_iph)) 2778 goto out; 2779 2780 ad->u.net.v4info.saddr = ih->saddr; 2781 ad->u.net.v4info.daddr = ih->daddr; 2782 ret = 0; 2783 2784 switch (ih->protocol) { 2785 case IPPROTO_TCP: { 2786 struct tcphdr _tcph, *th; 2787 2788 if (ntohs(ih->frag_off) & IP_OFFSET) 2789 break; 2790 2791 offset += ihlen; 2792 th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph); 2793 if (th == NULL) 2794 break; 2795 2796 ad->u.net.sport = th->source; 2797 ad->u.net.dport = th->dest; 2798 break; 2799 } 2800 2801 case IPPROTO_UDP: { 2802 struct udphdr _udph, *uh; 2803 2804 if (ntohs(ih->frag_off) & IP_OFFSET) 2805 break; 2806 2807 offset += ihlen; 2808 uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph); 2809 if (uh == NULL) 2810 break; 2811 2812 ad->u.net.sport = uh->source; 2813 ad->u.net.dport = uh->dest; 2814 break; 2815 } 2816 2817 default: 2818 break; 2819 } 2820 out: 2821 return ret; 2822 } 2823 2824 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE) 2825 2826 /* Returns error only if unable to parse addresses */ 2827 static int selinux_parse_skb_ipv6(struct sk_buff *skb, struct avc_audit_data *ad) 2828 { 2829 u8 nexthdr; 2830 int ret = -EINVAL, offset; 2831 struct ipv6hdr _ipv6h, *ip6; 2832 2833 offset = skb->nh.raw - skb->data; 2834 ip6 = skb_header_pointer(skb, offset, sizeof(_ipv6h), &_ipv6h); 2835 if (ip6 == NULL) 2836 goto out; 2837 2838 ipv6_addr_copy(&ad->u.net.v6info.saddr, &ip6->saddr); 2839 ipv6_addr_copy(&ad->u.net.v6info.daddr, &ip6->daddr); 2840 ret = 0; 2841 2842 nexthdr = ip6->nexthdr; 2843 offset += sizeof(_ipv6h); 2844 offset = ipv6_skip_exthdr(skb, offset, &nexthdr); 2845 if (offset < 0) 2846 goto out; 2847 2848 switch (nexthdr) { 2849 case IPPROTO_TCP: { 2850 struct tcphdr _tcph, *th; 2851 2852 th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph); 2853 if (th == NULL) 2854 break; 2855 2856 ad->u.net.sport = th->source; 2857 ad->u.net.dport = th->dest; 2858 break; 2859 } 2860 2861 case IPPROTO_UDP: { 2862 struct udphdr _udph, *uh; 2863 2864 uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph); 2865 if (uh == NULL) 2866 break; 2867 2868 ad->u.net.sport = uh->source; 2869 ad->u.net.dport = uh->dest; 2870 break; 2871 } 2872 2873 /* includes fragments */ 2874 default: 2875 break; 2876 } 2877 out: 2878 return ret; 2879 } 2880 2881 #endif /* IPV6 */ 2882 2883 static int selinux_parse_skb(struct sk_buff *skb, struct avc_audit_data *ad, 2884 char **addrp, int *len, int src) 2885 { 2886 int ret = 0; 2887 2888 switch (ad->u.net.family) { 2889 case PF_INET: 2890 ret = selinux_parse_skb_ipv4(skb, ad); 2891 if (ret || !addrp) 2892 break; 2893 *len = 4; 2894 *addrp = (char *)(src ? &ad->u.net.v4info.saddr : 2895 &ad->u.net.v4info.daddr); 2896 break; 2897 2898 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE) 2899 case PF_INET6: 2900 ret = selinux_parse_skb_ipv6(skb, ad); 2901 if (ret || !addrp) 2902 break; 2903 *len = 16; 2904 *addrp = (char *)(src ? &ad->u.net.v6info.saddr : 2905 &ad->u.net.v6info.daddr); 2906 break; 2907 #endif /* IPV6 */ 2908 default: 2909 break; 2910 } 2911 2912 return ret; 2913 } 2914 2915 /* socket security operations */ 2916 static int socket_has_perm(struct task_struct *task, struct socket *sock, 2917 u32 perms) 2918 { 2919 struct inode_security_struct *isec; 2920 struct task_security_struct *tsec; 2921 struct avc_audit_data ad; 2922 int err = 0; 2923 2924 tsec = task->security; 2925 isec = SOCK_INODE(sock)->i_security; 2926 2927 if (isec->sid == SECINITSID_KERNEL) 2928 goto out; 2929 2930 AVC_AUDIT_DATA_INIT(&ad,NET); 2931 ad.u.net.sk = sock->sk; 2932 err = avc_has_perm(tsec->sid, isec->sid, isec->sclass, perms, &ad); 2933 2934 out: 2935 return err; 2936 } 2937 2938 static int selinux_socket_create(int family, int type, 2939 int protocol, int kern) 2940 { 2941 int err = 0; 2942 struct task_security_struct *tsec; 2943 2944 if (kern) 2945 goto out; 2946 2947 tsec = current->security; 2948 err = avc_has_perm(tsec->sid, tsec->sid, 2949 socket_type_to_security_class(family, type, 2950 protocol), SOCKET__CREATE, NULL); 2951 2952 out: 2953 return err; 2954 } 2955 2956 static void selinux_socket_post_create(struct socket *sock, int family, 2957 int type, int protocol, int kern) 2958 { 2959 struct inode_security_struct *isec; 2960 struct task_security_struct *tsec; 2961 2962 isec = SOCK_INODE(sock)->i_security; 2963 2964 tsec = current->security; 2965 isec->sclass = socket_type_to_security_class(family, type, protocol); 2966 isec->sid = kern ? SECINITSID_KERNEL : tsec->sid; 2967 isec->initialized = 1; 2968 2969 return; 2970 } 2971 2972 /* Range of port numbers used to automatically bind. 2973 Need to determine whether we should perform a name_bind 2974 permission check between the socket and the port number. */ 2975 #define ip_local_port_range_0 sysctl_local_port_range[0] 2976 #define ip_local_port_range_1 sysctl_local_port_range[1] 2977 2978 static int selinux_socket_bind(struct socket *sock, struct sockaddr *address, int addrlen) 2979 { 2980 u16 family; 2981 int err; 2982 2983 err = socket_has_perm(current, sock, SOCKET__BIND); 2984 if (err) 2985 goto out; 2986 2987 /* 2988 * If PF_INET or PF_INET6, check name_bind permission for the port. 2989 * Multiple address binding for SCTP is not supported yet: we just 2990 * check the first address now. 2991 */ 2992 family = sock->sk->sk_family; 2993 if (family == PF_INET || family == PF_INET6) { 2994 char *addrp; 2995 struct inode_security_struct *isec; 2996 struct task_security_struct *tsec; 2997 struct avc_audit_data ad; 2998 struct sockaddr_in *addr4 = NULL; 2999 struct sockaddr_in6 *addr6 = NULL; 3000 unsigned short snum; 3001 struct sock *sk = sock->sk; 3002 u32 sid, node_perm, addrlen; 3003 3004 tsec = current->security; 3005 isec = SOCK_INODE(sock)->i_security; 3006 3007 if (family == PF_INET) { 3008 addr4 = (struct sockaddr_in *)address; 3009 snum = ntohs(addr4->sin_port); 3010 addrlen = sizeof(addr4->sin_addr.s_addr); 3011 addrp = (char *)&addr4->sin_addr.s_addr; 3012 } else { 3013 addr6 = (struct sockaddr_in6 *)address; 3014 snum = ntohs(addr6->sin6_port); 3015 addrlen = sizeof(addr6->sin6_addr.s6_addr); 3016 addrp = (char *)&addr6->sin6_addr.s6_addr; 3017 } 3018 3019 if (snum&&(snum < max(PROT_SOCK,ip_local_port_range_0) || 3020 snum > ip_local_port_range_1)) { 3021 err = security_port_sid(sk->sk_family, sk->sk_type, 3022 sk->sk_protocol, snum, &sid); 3023 if (err) 3024 goto out; 3025 AVC_AUDIT_DATA_INIT(&ad,NET); 3026 ad.u.net.sport = htons(snum); 3027 ad.u.net.family = family; 3028 err = avc_has_perm(isec->sid, sid, 3029 isec->sclass, 3030 SOCKET__NAME_BIND, &ad); 3031 if (err) 3032 goto out; 3033 } 3034 3035 switch(isec->sclass) { 3036 case SECCLASS_TCP_SOCKET: 3037 node_perm = TCP_SOCKET__NODE_BIND; 3038 break; 3039 3040 case SECCLASS_UDP_SOCKET: 3041 node_perm = UDP_SOCKET__NODE_BIND; 3042 break; 3043 3044 default: 3045 node_perm = RAWIP_SOCKET__NODE_BIND; 3046 break; 3047 } 3048 3049 err = security_node_sid(family, addrp, addrlen, &sid); 3050 if (err) 3051 goto out; 3052 3053 AVC_AUDIT_DATA_INIT(&ad,NET); 3054 ad.u.net.sport = htons(snum); 3055 ad.u.net.family = family; 3056 3057 if (family == PF_INET) 3058 ad.u.net.v4info.saddr = addr4->sin_addr.s_addr; 3059 else 3060 ipv6_addr_copy(&ad.u.net.v6info.saddr, &addr6->sin6_addr); 3061 3062 err = avc_has_perm(isec->sid, sid, 3063 isec->sclass, node_perm, &ad); 3064 if (err) 3065 goto out; 3066 } 3067 out: 3068 return err; 3069 } 3070 3071 static int selinux_socket_connect(struct socket *sock, struct sockaddr *address, int addrlen) 3072 { 3073 struct inode_security_struct *isec; 3074 int err; 3075 3076 err = socket_has_perm(current, sock, SOCKET__CONNECT); 3077 if (err) 3078 return err; 3079 3080 /* 3081 * If a TCP socket, check name_connect permission for the port. 3082 */ 3083 isec = SOCK_INODE(sock)->i_security; 3084 if (isec->sclass == SECCLASS_TCP_SOCKET) { 3085 struct sock *sk = sock->sk; 3086 struct avc_audit_data ad; 3087 struct sockaddr_in *addr4 = NULL; 3088 struct sockaddr_in6 *addr6 = NULL; 3089 unsigned short snum; 3090 u32 sid; 3091 3092 if (sk->sk_family == PF_INET) { 3093 addr4 = (struct sockaddr_in *)address; 3094 if (addrlen < sizeof(struct sockaddr_in)) 3095 return -EINVAL; 3096 snum = ntohs(addr4->sin_port); 3097 } else { 3098 addr6 = (struct sockaddr_in6 *)address; 3099 if (addrlen < SIN6_LEN_RFC2133) 3100 return -EINVAL; 3101 snum = ntohs(addr6->sin6_port); 3102 } 3103 3104 err = security_port_sid(sk->sk_family, sk->sk_type, 3105 sk->sk_protocol, snum, &sid); 3106 if (err) 3107 goto out; 3108 3109 AVC_AUDIT_DATA_INIT(&ad,NET); 3110 ad.u.net.dport = htons(snum); 3111 ad.u.net.family = sk->sk_family; 3112 err = avc_has_perm(isec->sid, sid, isec->sclass, 3113 TCP_SOCKET__NAME_CONNECT, &ad); 3114 if (err) 3115 goto out; 3116 } 3117 3118 out: 3119 return err; 3120 } 3121 3122 static int selinux_socket_listen(struct socket *sock, int backlog) 3123 { 3124 return socket_has_perm(current, sock, SOCKET__LISTEN); 3125 } 3126 3127 static int selinux_socket_accept(struct socket *sock, struct socket *newsock) 3128 { 3129 int err; 3130 struct inode_security_struct *isec; 3131 struct inode_security_struct *newisec; 3132 3133 err = socket_has_perm(current, sock, SOCKET__ACCEPT); 3134 if (err) 3135 return err; 3136 3137 newisec = SOCK_INODE(newsock)->i_security; 3138 3139 isec = SOCK_INODE(sock)->i_security; 3140 newisec->sclass = isec->sclass; 3141 newisec->sid = isec->sid; 3142 newisec->initialized = 1; 3143 3144 return 0; 3145 } 3146 3147 static int selinux_socket_sendmsg(struct socket *sock, struct msghdr *msg, 3148 int size) 3149 { 3150 return socket_has_perm(current, sock, SOCKET__WRITE); 3151 } 3152 3153 static int selinux_socket_recvmsg(struct socket *sock, struct msghdr *msg, 3154 int size, int flags) 3155 { 3156 return socket_has_perm(current, sock, SOCKET__READ); 3157 } 3158 3159 static int selinux_socket_getsockname(struct socket *sock) 3160 { 3161 return socket_has_perm(current, sock, SOCKET__GETATTR); 3162 } 3163 3164 static int selinux_socket_getpeername(struct socket *sock) 3165 { 3166 return socket_has_perm(current, sock, SOCKET__GETATTR); 3167 } 3168 3169 static int selinux_socket_setsockopt(struct socket *sock,int level,int optname) 3170 { 3171 return socket_has_perm(current, sock, SOCKET__SETOPT); 3172 } 3173 3174 static int selinux_socket_getsockopt(struct socket *sock, int level, 3175 int optname) 3176 { 3177 return socket_has_perm(current, sock, SOCKET__GETOPT); 3178 } 3179 3180 static int selinux_socket_shutdown(struct socket *sock, int how) 3181 { 3182 return socket_has_perm(current, sock, SOCKET__SHUTDOWN); 3183 } 3184 3185 static int selinux_socket_unix_stream_connect(struct socket *sock, 3186 struct socket *other, 3187 struct sock *newsk) 3188 { 3189 struct sk_security_struct *ssec; 3190 struct inode_security_struct *isec; 3191 struct inode_security_struct *other_isec; 3192 struct avc_audit_data ad; 3193 int err; 3194 3195 err = secondary_ops->unix_stream_connect(sock, other, newsk); 3196 if (err) 3197 return err; 3198 3199 isec = SOCK_INODE(sock)->i_security; 3200 other_isec = SOCK_INODE(other)->i_security; 3201 3202 AVC_AUDIT_DATA_INIT(&ad,NET); 3203 ad.u.net.sk = other->sk; 3204 3205 err = avc_has_perm(isec->sid, other_isec->sid, 3206 isec->sclass, 3207 UNIX_STREAM_SOCKET__CONNECTTO, &ad); 3208 if (err) 3209 return err; 3210 3211 /* connecting socket */ 3212 ssec = sock->sk->sk_security; 3213 ssec->peer_sid = other_isec->sid; 3214 3215 /* server child socket */ 3216 ssec = newsk->sk_security; 3217 ssec->peer_sid = isec->sid; 3218 3219 return 0; 3220 } 3221 3222 static int selinux_socket_unix_may_send(struct socket *sock, 3223 struct socket *other) 3224 { 3225 struct inode_security_struct *isec; 3226 struct inode_security_struct *other_isec; 3227 struct avc_audit_data ad; 3228 int err; 3229 3230 isec = SOCK_INODE(sock)->i_security; 3231 other_isec = SOCK_INODE(other)->i_security; 3232 3233 AVC_AUDIT_DATA_INIT(&ad,NET); 3234 ad.u.net.sk = other->sk; 3235 3236 err = avc_has_perm(isec->sid, other_isec->sid, 3237 isec->sclass, SOCKET__SENDTO, &ad); 3238 if (err) 3239 return err; 3240 3241 return 0; 3242 } 3243 3244 static int selinux_socket_sock_rcv_skb(struct sock *sk, struct sk_buff *skb) 3245 { 3246 u16 family; 3247 char *addrp; 3248 int len, err = 0; 3249 u32 netif_perm, node_perm, node_sid, if_sid, recv_perm = 0; 3250 u32 sock_sid = 0; 3251 u16 sock_class = 0; 3252 struct socket *sock; 3253 struct net_device *dev; 3254 struct avc_audit_data ad; 3255 3256 family = sk->sk_family; 3257 if (family != PF_INET && family != PF_INET6) 3258 goto out; 3259 3260 /* Handle mapped IPv4 packets arriving via IPv6 sockets */ 3261 if (family == PF_INET6 && skb->protocol == ntohs(ETH_P_IP)) 3262 family = PF_INET; 3263 3264 read_lock_bh(&sk->sk_callback_lock); 3265 sock = sk->sk_socket; 3266 if (sock) { 3267 struct inode *inode; 3268 inode = SOCK_INODE(sock); 3269 if (inode) { 3270 struct inode_security_struct *isec; 3271 isec = inode->i_security; 3272 sock_sid = isec->sid; 3273 sock_class = isec->sclass; 3274 } 3275 } 3276 read_unlock_bh(&sk->sk_callback_lock); 3277 if (!sock_sid) 3278 goto out; 3279 3280 dev = skb->dev; 3281 if (!dev) 3282 goto out; 3283 3284 err = sel_netif_sids(dev, &if_sid, NULL); 3285 if (err) 3286 goto out; 3287 3288 switch (sock_class) { 3289 case SECCLASS_UDP_SOCKET: 3290 netif_perm = NETIF__UDP_RECV; 3291 node_perm = NODE__UDP_RECV; 3292 recv_perm = UDP_SOCKET__RECV_MSG; 3293 break; 3294 3295 case SECCLASS_TCP_SOCKET: 3296 netif_perm = NETIF__TCP_RECV; 3297 node_perm = NODE__TCP_RECV; 3298 recv_perm = TCP_SOCKET__RECV_MSG; 3299 break; 3300 3301 default: 3302 netif_perm = NETIF__RAWIP_RECV; 3303 node_perm = NODE__RAWIP_RECV; 3304 break; 3305 } 3306 3307 AVC_AUDIT_DATA_INIT(&ad, NET); 3308 ad.u.net.netif = dev->name; 3309 ad.u.net.family = family; 3310 3311 err = selinux_parse_skb(skb, &ad, &addrp, &len, 1); 3312 if (err) 3313 goto out; 3314 3315 err = avc_has_perm(sock_sid, if_sid, SECCLASS_NETIF, netif_perm, &ad); 3316 if (err) 3317 goto out; 3318 3319 /* Fixme: this lookup is inefficient */ 3320 err = security_node_sid(family, addrp, len, &node_sid); 3321 if (err) 3322 goto out; 3323 3324 err = avc_has_perm(sock_sid, node_sid, SECCLASS_NODE, node_perm, &ad); 3325 if (err) 3326 goto out; 3327 3328 if (recv_perm) { 3329 u32 port_sid; 3330 3331 /* Fixme: make this more efficient */ 3332 err = security_port_sid(sk->sk_family, sk->sk_type, 3333 sk->sk_protocol, ntohs(ad.u.net.sport), 3334 &port_sid); 3335 if (err) 3336 goto out; 3337 3338 err = avc_has_perm(sock_sid, port_sid, 3339 sock_class, recv_perm, &ad); 3340 } 3341 out: 3342 return err; 3343 } 3344 3345 static int selinux_socket_getpeersec(struct socket *sock, char __user *optval, 3346 int __user *optlen, unsigned len) 3347 { 3348 int err = 0; 3349 char *scontext; 3350 u32 scontext_len; 3351 struct sk_security_struct *ssec; 3352 struct inode_security_struct *isec; 3353 3354 isec = SOCK_INODE(sock)->i_security; 3355 if (isec->sclass != SECCLASS_UNIX_STREAM_SOCKET) { 3356 err = -ENOPROTOOPT; 3357 goto out; 3358 } 3359 3360 ssec = sock->sk->sk_security; 3361 3362 err = security_sid_to_context(ssec->peer_sid, &scontext, &scontext_len); 3363 if (err) 3364 goto out; 3365 3366 if (scontext_len > len) { 3367 err = -ERANGE; 3368 goto out_len; 3369 } 3370 3371 if (copy_to_user(optval, scontext, scontext_len)) 3372 err = -EFAULT; 3373 3374 out_len: 3375 if (put_user(scontext_len, optlen)) 3376 err = -EFAULT; 3377 3378 kfree(scontext); 3379 out: 3380 return err; 3381 } 3382 3383 static int selinux_sk_alloc_security(struct sock *sk, int family, int priority) 3384 { 3385 return sk_alloc_security(sk, family, priority); 3386 } 3387 3388 static void selinux_sk_free_security(struct sock *sk) 3389 { 3390 sk_free_security(sk); 3391 } 3392 3393 static int selinux_nlmsg_perm(struct sock *sk, struct sk_buff *skb) 3394 { 3395 int err = 0; 3396 u32 perm; 3397 struct nlmsghdr *nlh; 3398 struct socket *sock = sk->sk_socket; 3399 struct inode_security_struct *isec = SOCK_INODE(sock)->i_security; 3400 3401 if (skb->len < NLMSG_SPACE(0)) { 3402 err = -EINVAL; 3403 goto out; 3404 } 3405 nlh = (struct nlmsghdr *)skb->data; 3406 3407 err = selinux_nlmsg_lookup(isec->sclass, nlh->nlmsg_type, &perm); 3408 if (err) { 3409 if (err == -EINVAL) { 3410 audit_log(current->audit_context, GFP_KERNEL, AUDIT_SELINUX_ERR, 3411 "SELinux: unrecognized netlink message" 3412 " type=%hu for sclass=%hu\n", 3413 nlh->nlmsg_type, isec->sclass); 3414 if (!selinux_enforcing) 3415 err = 0; 3416 } 3417 3418 /* Ignore */ 3419 if (err == -ENOENT) 3420 err = 0; 3421 goto out; 3422 } 3423 3424 err = socket_has_perm(current, sock, perm); 3425 out: 3426 return err; 3427 } 3428 3429 #ifdef CONFIG_NETFILTER 3430 3431 static unsigned int selinux_ip_postroute_last(unsigned int hooknum, 3432 struct sk_buff **pskb, 3433 const struct net_device *in, 3434 const struct net_device *out, 3435 int (*okfn)(struct sk_buff *), 3436 u16 family) 3437 { 3438 char *addrp; 3439 int len, err = NF_ACCEPT; 3440 u32 netif_perm, node_perm, node_sid, if_sid, send_perm = 0; 3441 struct sock *sk; 3442 struct socket *sock; 3443 struct inode *inode; 3444 struct sk_buff *skb = *pskb; 3445 struct inode_security_struct *isec; 3446 struct avc_audit_data ad; 3447 struct net_device *dev = (struct net_device *)out; 3448 3449 sk = skb->sk; 3450 if (!sk) 3451 goto out; 3452 3453 sock = sk->sk_socket; 3454 if (!sock) 3455 goto out; 3456 3457 inode = SOCK_INODE(sock); 3458 if (!inode) 3459 goto out; 3460 3461 err = sel_netif_sids(dev, &if_sid, NULL); 3462 if (err) 3463 goto out; 3464 3465 isec = inode->i_security; 3466 3467 switch (isec->sclass) { 3468 case SECCLASS_UDP_SOCKET: 3469 netif_perm = NETIF__UDP_SEND; 3470 node_perm = NODE__UDP_SEND; 3471 send_perm = UDP_SOCKET__SEND_MSG; 3472 break; 3473 3474 case SECCLASS_TCP_SOCKET: 3475 netif_perm = NETIF__TCP_SEND; 3476 node_perm = NODE__TCP_SEND; 3477 send_perm = TCP_SOCKET__SEND_MSG; 3478 break; 3479 3480 default: 3481 netif_perm = NETIF__RAWIP_SEND; 3482 node_perm = NODE__RAWIP_SEND; 3483 break; 3484 } 3485 3486 3487 AVC_AUDIT_DATA_INIT(&ad, NET); 3488 ad.u.net.netif = dev->name; 3489 ad.u.net.family = family; 3490 3491 err = selinux_parse_skb(skb, &ad, &addrp, 3492 &len, 0) ? NF_DROP : NF_ACCEPT; 3493 if (err != NF_ACCEPT) 3494 goto out; 3495 3496 err = avc_has_perm(isec->sid, if_sid, SECCLASS_NETIF, 3497 netif_perm, &ad) ? NF_DROP : NF_ACCEPT; 3498 if (err != NF_ACCEPT) 3499 goto out; 3500 3501 /* Fixme: this lookup is inefficient */ 3502 err = security_node_sid(family, addrp, len, 3503 &node_sid) ? NF_DROP : NF_ACCEPT; 3504 if (err != NF_ACCEPT) 3505 goto out; 3506 3507 err = avc_has_perm(isec->sid, node_sid, SECCLASS_NODE, 3508 node_perm, &ad) ? NF_DROP : NF_ACCEPT; 3509 if (err != NF_ACCEPT) 3510 goto out; 3511 3512 if (send_perm) { 3513 u32 port_sid; 3514 3515 /* Fixme: make this more efficient */ 3516 err = security_port_sid(sk->sk_family, 3517 sk->sk_type, 3518 sk->sk_protocol, 3519 ntohs(ad.u.net.dport), 3520 &port_sid) ? NF_DROP : NF_ACCEPT; 3521 if (err != NF_ACCEPT) 3522 goto out; 3523 3524 err = avc_has_perm(isec->sid, port_sid, isec->sclass, 3525 send_perm, &ad) ? NF_DROP : NF_ACCEPT; 3526 } 3527 3528 out: 3529 return err; 3530 } 3531 3532 static unsigned int selinux_ipv4_postroute_last(unsigned int hooknum, 3533 struct sk_buff **pskb, 3534 const struct net_device *in, 3535 const struct net_device *out, 3536 int (*okfn)(struct sk_buff *)) 3537 { 3538 return selinux_ip_postroute_last(hooknum, pskb, in, out, okfn, PF_INET); 3539 } 3540 3541 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE) 3542 3543 static unsigned int selinux_ipv6_postroute_last(unsigned int hooknum, 3544 struct sk_buff **pskb, 3545 const struct net_device *in, 3546 const struct net_device *out, 3547 int (*okfn)(struct sk_buff *)) 3548 { 3549 return selinux_ip_postroute_last(hooknum, pskb, in, out, okfn, PF_INET6); 3550 } 3551 3552 #endif /* IPV6 */ 3553 3554 #endif /* CONFIG_NETFILTER */ 3555 3556 #else 3557 3558 static inline int selinux_nlmsg_perm(struct sock *sk, struct sk_buff *skb) 3559 { 3560 return 0; 3561 } 3562 3563 #endif /* CONFIG_SECURITY_NETWORK */ 3564 3565 static int selinux_netlink_send(struct sock *sk, struct sk_buff *skb) 3566 { 3567 struct task_security_struct *tsec; 3568 struct av_decision avd; 3569 int err; 3570 3571 err = secondary_ops->netlink_send(sk, skb); 3572 if (err) 3573 return err; 3574 3575 tsec = current->security; 3576 3577 avd.allowed = 0; 3578 avc_has_perm_noaudit(tsec->sid, tsec->sid, 3579 SECCLASS_CAPABILITY, ~0, &avd); 3580 cap_mask(NETLINK_CB(skb).eff_cap, avd.allowed); 3581 3582 if (policydb_loaded_version >= POLICYDB_VERSION_NLCLASS) 3583 err = selinux_nlmsg_perm(sk, skb); 3584 3585 return err; 3586 } 3587 3588 static int selinux_netlink_recv(struct sk_buff *skb) 3589 { 3590 if (!cap_raised(NETLINK_CB(skb).eff_cap, CAP_NET_ADMIN)) 3591 return -EPERM; 3592 return 0; 3593 } 3594 3595 static int ipc_alloc_security(struct task_struct *task, 3596 struct kern_ipc_perm *perm, 3597 u16 sclass) 3598 { 3599 struct task_security_struct *tsec = task->security; 3600 struct ipc_security_struct *isec; 3601 3602 isec = kmalloc(sizeof(struct ipc_security_struct), GFP_KERNEL); 3603 if (!isec) 3604 return -ENOMEM; 3605 3606 memset(isec, 0, sizeof(struct ipc_security_struct)); 3607 isec->magic = SELINUX_MAGIC; 3608 isec->sclass = sclass; 3609 isec->ipc_perm = perm; 3610 if (tsec) { 3611 isec->sid = tsec->sid; 3612 } else { 3613 isec->sid = SECINITSID_UNLABELED; 3614 } 3615 perm->security = isec; 3616 3617 return 0; 3618 } 3619 3620 static void ipc_free_security(struct kern_ipc_perm *perm) 3621 { 3622 struct ipc_security_struct *isec = perm->security; 3623 if (!isec || isec->magic != SELINUX_MAGIC) 3624 return; 3625 3626 perm->security = NULL; 3627 kfree(isec); 3628 } 3629 3630 static int msg_msg_alloc_security(struct msg_msg *msg) 3631 { 3632 struct msg_security_struct *msec; 3633 3634 msec = kmalloc(sizeof(struct msg_security_struct), GFP_KERNEL); 3635 if (!msec) 3636 return -ENOMEM; 3637 3638 memset(msec, 0, sizeof(struct msg_security_struct)); 3639 msec->magic = SELINUX_MAGIC; 3640 msec->msg = msg; 3641 msec->sid = SECINITSID_UNLABELED; 3642 msg->security = msec; 3643 3644 return 0; 3645 } 3646 3647 static void msg_msg_free_security(struct msg_msg *msg) 3648 { 3649 struct msg_security_struct *msec = msg->security; 3650 if (!msec || msec->magic != SELINUX_MAGIC) 3651 return; 3652 3653 msg->security = NULL; 3654 kfree(msec); 3655 } 3656 3657 static int ipc_has_perm(struct kern_ipc_perm *ipc_perms, 3658 u32 perms) 3659 { 3660 struct task_security_struct *tsec; 3661 struct ipc_security_struct *isec; 3662 struct avc_audit_data ad; 3663 3664 tsec = current->security; 3665 isec = ipc_perms->security; 3666 3667 AVC_AUDIT_DATA_INIT(&ad, IPC); 3668 ad.u.ipc_id = ipc_perms->key; 3669 3670 return avc_has_perm(tsec->sid, isec->sid, isec->sclass, perms, &ad); 3671 } 3672 3673 static int selinux_msg_msg_alloc_security(struct msg_msg *msg) 3674 { 3675 return msg_msg_alloc_security(msg); 3676 } 3677 3678 static void selinux_msg_msg_free_security(struct msg_msg *msg) 3679 { 3680 msg_msg_free_security(msg); 3681 } 3682 3683 /* message queue security operations */ 3684 static int selinux_msg_queue_alloc_security(struct msg_queue *msq) 3685 { 3686 struct task_security_struct *tsec; 3687 struct ipc_security_struct *isec; 3688 struct avc_audit_data ad; 3689 int rc; 3690 3691 rc = ipc_alloc_security(current, &msq->q_perm, SECCLASS_MSGQ); 3692 if (rc) 3693 return rc; 3694 3695 tsec = current->security; 3696 isec = msq->q_perm.security; 3697 3698 AVC_AUDIT_DATA_INIT(&ad, IPC); 3699 ad.u.ipc_id = msq->q_perm.key; 3700 3701 rc = avc_has_perm(tsec->sid, isec->sid, SECCLASS_MSGQ, 3702 MSGQ__CREATE, &ad); 3703 if (rc) { 3704 ipc_free_security(&msq->q_perm); 3705 return rc; 3706 } 3707 return 0; 3708 } 3709 3710 static void selinux_msg_queue_free_security(struct msg_queue *msq) 3711 { 3712 ipc_free_security(&msq->q_perm); 3713 } 3714 3715 static int selinux_msg_queue_associate(struct msg_queue *msq, int msqflg) 3716 { 3717 struct task_security_struct *tsec; 3718 struct ipc_security_struct *isec; 3719 struct avc_audit_data ad; 3720 3721 tsec = current->security; 3722 isec = msq->q_perm.security; 3723 3724 AVC_AUDIT_DATA_INIT(&ad, IPC); 3725 ad.u.ipc_id = msq->q_perm.key; 3726 3727 return avc_has_perm(tsec->sid, isec->sid, SECCLASS_MSGQ, 3728 MSGQ__ASSOCIATE, &ad); 3729 } 3730 3731 static int selinux_msg_queue_msgctl(struct msg_queue *msq, int cmd) 3732 { 3733 int err; 3734 int perms; 3735 3736 switch(cmd) { 3737 case IPC_INFO: 3738 case MSG_INFO: 3739 /* No specific object, just general system-wide information. */ 3740 return task_has_system(current, SYSTEM__IPC_INFO); 3741 case IPC_STAT: 3742 case MSG_STAT: 3743 perms = MSGQ__GETATTR | MSGQ__ASSOCIATE; 3744 break; 3745 case IPC_SET: 3746 perms = MSGQ__SETATTR; 3747 break; 3748 case IPC_RMID: 3749 perms = MSGQ__DESTROY; 3750 break; 3751 default: 3752 return 0; 3753 } 3754 3755 err = ipc_has_perm(&msq->q_perm, perms); 3756 return err; 3757 } 3758 3759 static int selinux_msg_queue_msgsnd(struct msg_queue *msq, struct msg_msg *msg, int msqflg) 3760 { 3761 struct task_security_struct *tsec; 3762 struct ipc_security_struct *isec; 3763 struct msg_security_struct *msec; 3764 struct avc_audit_data ad; 3765 int rc; 3766 3767 tsec = current->security; 3768 isec = msq->q_perm.security; 3769 msec = msg->security; 3770 3771 /* 3772 * First time through, need to assign label to the message 3773 */ 3774 if (msec->sid == SECINITSID_UNLABELED) { 3775 /* 3776 * Compute new sid based on current process and 3777 * message queue this message will be stored in 3778 */ 3779 rc = security_transition_sid(tsec->sid, 3780 isec->sid, 3781 SECCLASS_MSG, 3782 &msec->sid); 3783 if (rc) 3784 return rc; 3785 } 3786 3787 AVC_AUDIT_DATA_INIT(&ad, IPC); 3788 ad.u.ipc_id = msq->q_perm.key; 3789 3790 /* Can this process write to the queue? */ 3791 rc = avc_has_perm(tsec->sid, isec->sid, SECCLASS_MSGQ, 3792 MSGQ__WRITE, &ad); 3793 if (!rc) 3794 /* Can this process send the message */ 3795 rc = avc_has_perm(tsec->sid, msec->sid, 3796 SECCLASS_MSG, MSG__SEND, &ad); 3797 if (!rc) 3798 /* Can the message be put in the queue? */ 3799 rc = avc_has_perm(msec->sid, isec->sid, 3800 SECCLASS_MSGQ, MSGQ__ENQUEUE, &ad); 3801 3802 return rc; 3803 } 3804 3805 static int selinux_msg_queue_msgrcv(struct msg_queue *msq, struct msg_msg *msg, 3806 struct task_struct *target, 3807 long type, int mode) 3808 { 3809 struct task_security_struct *tsec; 3810 struct ipc_security_struct *isec; 3811 struct msg_security_struct *msec; 3812 struct avc_audit_data ad; 3813 int rc; 3814 3815 tsec = target->security; 3816 isec = msq->q_perm.security; 3817 msec = msg->security; 3818 3819 AVC_AUDIT_DATA_INIT(&ad, IPC); 3820 ad.u.ipc_id = msq->q_perm.key; 3821 3822 rc = avc_has_perm(tsec->sid, isec->sid, 3823 SECCLASS_MSGQ, MSGQ__READ, &ad); 3824 if (!rc) 3825 rc = avc_has_perm(tsec->sid, msec->sid, 3826 SECCLASS_MSG, MSG__RECEIVE, &ad); 3827 return rc; 3828 } 3829 3830 /* Shared Memory security operations */ 3831 static int selinux_shm_alloc_security(struct shmid_kernel *shp) 3832 { 3833 struct task_security_struct *tsec; 3834 struct ipc_security_struct *isec; 3835 struct avc_audit_data ad; 3836 int rc; 3837 3838 rc = ipc_alloc_security(current, &shp->shm_perm, SECCLASS_SHM); 3839 if (rc) 3840 return rc; 3841 3842 tsec = current->security; 3843 isec = shp->shm_perm.security; 3844 3845 AVC_AUDIT_DATA_INIT(&ad, IPC); 3846 ad.u.ipc_id = shp->shm_perm.key; 3847 3848 rc = avc_has_perm(tsec->sid, isec->sid, SECCLASS_SHM, 3849 SHM__CREATE, &ad); 3850 if (rc) { 3851 ipc_free_security(&shp->shm_perm); 3852 return rc; 3853 } 3854 return 0; 3855 } 3856 3857 static void selinux_shm_free_security(struct shmid_kernel *shp) 3858 { 3859 ipc_free_security(&shp->shm_perm); 3860 } 3861 3862 static int selinux_shm_associate(struct shmid_kernel *shp, int shmflg) 3863 { 3864 struct task_security_struct *tsec; 3865 struct ipc_security_struct *isec; 3866 struct avc_audit_data ad; 3867 3868 tsec = current->security; 3869 isec = shp->shm_perm.security; 3870 3871 AVC_AUDIT_DATA_INIT(&ad, IPC); 3872 ad.u.ipc_id = shp->shm_perm.key; 3873 3874 return avc_has_perm(tsec->sid, isec->sid, SECCLASS_SHM, 3875 SHM__ASSOCIATE, &ad); 3876 } 3877 3878 /* Note, at this point, shp is locked down */ 3879 static int selinux_shm_shmctl(struct shmid_kernel *shp, int cmd) 3880 { 3881 int perms; 3882 int err; 3883 3884 switch(cmd) { 3885 case IPC_INFO: 3886 case SHM_INFO: 3887 /* No specific object, just general system-wide information. */ 3888 return task_has_system(current, SYSTEM__IPC_INFO); 3889 case IPC_STAT: 3890 case SHM_STAT: 3891 perms = SHM__GETATTR | SHM__ASSOCIATE; 3892 break; 3893 case IPC_SET: 3894 perms = SHM__SETATTR; 3895 break; 3896 case SHM_LOCK: 3897 case SHM_UNLOCK: 3898 perms = SHM__LOCK; 3899 break; 3900 case IPC_RMID: 3901 perms = SHM__DESTROY; 3902 break; 3903 default: 3904 return 0; 3905 } 3906 3907 err = ipc_has_perm(&shp->shm_perm, perms); 3908 return err; 3909 } 3910 3911 static int selinux_shm_shmat(struct shmid_kernel *shp, 3912 char __user *shmaddr, int shmflg) 3913 { 3914 u32 perms; 3915 int rc; 3916 3917 rc = secondary_ops->shm_shmat(shp, shmaddr, shmflg); 3918 if (rc) 3919 return rc; 3920 3921 if (shmflg & SHM_RDONLY) 3922 perms = SHM__READ; 3923 else 3924 perms = SHM__READ | SHM__WRITE; 3925 3926 return ipc_has_perm(&shp->shm_perm, perms); 3927 } 3928 3929 /* Semaphore security operations */ 3930 static int selinux_sem_alloc_security(struct sem_array *sma) 3931 { 3932 struct task_security_struct *tsec; 3933 struct ipc_security_struct *isec; 3934 struct avc_audit_data ad; 3935 int rc; 3936 3937 rc = ipc_alloc_security(current, &sma->sem_perm, SECCLASS_SEM); 3938 if (rc) 3939 return rc; 3940 3941 tsec = current->security; 3942 isec = sma->sem_perm.security; 3943 3944 AVC_AUDIT_DATA_INIT(&ad, IPC); 3945 ad.u.ipc_id = sma->sem_perm.key; 3946 3947 rc = avc_has_perm(tsec->sid, isec->sid, SECCLASS_SEM, 3948 SEM__CREATE, &ad); 3949 if (rc) { 3950 ipc_free_security(&sma->sem_perm); 3951 return rc; 3952 } 3953 return 0; 3954 } 3955 3956 static void selinux_sem_free_security(struct sem_array *sma) 3957 { 3958 ipc_free_security(&sma->sem_perm); 3959 } 3960 3961 static int selinux_sem_associate(struct sem_array *sma, int semflg) 3962 { 3963 struct task_security_struct *tsec; 3964 struct ipc_security_struct *isec; 3965 struct avc_audit_data ad; 3966 3967 tsec = current->security; 3968 isec = sma->sem_perm.security; 3969 3970 AVC_AUDIT_DATA_INIT(&ad, IPC); 3971 ad.u.ipc_id = sma->sem_perm.key; 3972 3973 return avc_has_perm(tsec->sid, isec->sid, SECCLASS_SEM, 3974 SEM__ASSOCIATE, &ad); 3975 } 3976 3977 /* Note, at this point, sma is locked down */ 3978 static int selinux_sem_semctl(struct sem_array *sma, int cmd) 3979 { 3980 int err; 3981 u32 perms; 3982 3983 switch(cmd) { 3984 case IPC_INFO: 3985 case SEM_INFO: 3986 /* No specific object, just general system-wide information. */ 3987 return task_has_system(current, SYSTEM__IPC_INFO); 3988 case GETPID: 3989 case GETNCNT: 3990 case GETZCNT: 3991 perms = SEM__GETATTR; 3992 break; 3993 case GETVAL: 3994 case GETALL: 3995 perms = SEM__READ; 3996 break; 3997 case SETVAL: 3998 case SETALL: 3999 perms = SEM__WRITE; 4000 break; 4001 case IPC_RMID: 4002 perms = SEM__DESTROY; 4003 break; 4004 case IPC_SET: 4005 perms = SEM__SETATTR; 4006 break; 4007 case IPC_STAT: 4008 case SEM_STAT: 4009 perms = SEM__GETATTR | SEM__ASSOCIATE; 4010 break; 4011 default: 4012 return 0; 4013 } 4014 4015 err = ipc_has_perm(&sma->sem_perm, perms); 4016 return err; 4017 } 4018 4019 static int selinux_sem_semop(struct sem_array *sma, 4020 struct sembuf *sops, unsigned nsops, int alter) 4021 { 4022 u32 perms; 4023 4024 if (alter) 4025 perms = SEM__READ | SEM__WRITE; 4026 else 4027 perms = SEM__READ; 4028 4029 return ipc_has_perm(&sma->sem_perm, perms); 4030 } 4031 4032 static int selinux_ipc_permission(struct kern_ipc_perm *ipcp, short flag) 4033 { 4034 u32 av = 0; 4035 4036 av = 0; 4037 if (flag & S_IRUGO) 4038 av |= IPC__UNIX_READ; 4039 if (flag & S_IWUGO) 4040 av |= IPC__UNIX_WRITE; 4041 4042 if (av == 0) 4043 return 0; 4044 4045 return ipc_has_perm(ipcp, av); 4046 } 4047 4048 /* module stacking operations */ 4049 static int selinux_register_security (const char *name, struct security_operations *ops) 4050 { 4051 if (secondary_ops != original_ops) { 4052 printk(KERN_INFO "%s: There is already a secondary security " 4053 "module registered.\n", __FUNCTION__); 4054 return -EINVAL; 4055 } 4056 4057 secondary_ops = ops; 4058 4059 printk(KERN_INFO "%s: Registering secondary module %s\n", 4060 __FUNCTION__, 4061 name); 4062 4063 return 0; 4064 } 4065 4066 static int selinux_unregister_security (const char *name, struct security_operations *ops) 4067 { 4068 if (ops != secondary_ops) { 4069 printk (KERN_INFO "%s: trying to unregister a security module " 4070 "that is not registered.\n", __FUNCTION__); 4071 return -EINVAL; 4072 } 4073 4074 secondary_ops = original_ops; 4075 4076 return 0; 4077 } 4078 4079 static void selinux_d_instantiate (struct dentry *dentry, struct inode *inode) 4080 { 4081 if (inode) 4082 inode_doinit_with_dentry(inode, dentry); 4083 } 4084 4085 static int selinux_getprocattr(struct task_struct *p, 4086 char *name, void *value, size_t size) 4087 { 4088 struct task_security_struct *tsec; 4089 u32 sid, len; 4090 char *context; 4091 int error; 4092 4093 if (current != p) { 4094 error = task_has_perm(current, p, PROCESS__GETATTR); 4095 if (error) 4096 return error; 4097 } 4098 4099 if (!size) 4100 return -ERANGE; 4101 4102 tsec = p->security; 4103 4104 if (!strcmp(name, "current")) 4105 sid = tsec->sid; 4106 else if (!strcmp(name, "prev")) 4107 sid = tsec->osid; 4108 else if (!strcmp(name, "exec")) 4109 sid = tsec->exec_sid; 4110 else if (!strcmp(name, "fscreate")) 4111 sid = tsec->create_sid; 4112 else 4113 return -EINVAL; 4114 4115 if (!sid) 4116 return 0; 4117 4118 error = security_sid_to_context(sid, &context, &len); 4119 if (error) 4120 return error; 4121 if (len > size) { 4122 kfree(context); 4123 return -ERANGE; 4124 } 4125 memcpy(value, context, len); 4126 kfree(context); 4127 return len; 4128 } 4129 4130 static int selinux_setprocattr(struct task_struct *p, 4131 char *name, void *value, size_t size) 4132 { 4133 struct task_security_struct *tsec; 4134 u32 sid = 0; 4135 int error; 4136 char *str = value; 4137 4138 if (current != p) { 4139 /* SELinux only allows a process to change its own 4140 security attributes. */ 4141 return -EACCES; 4142 } 4143 4144 /* 4145 * Basic control over ability to set these attributes at all. 4146 * current == p, but we'll pass them separately in case the 4147 * above restriction is ever removed. 4148 */ 4149 if (!strcmp(name, "exec")) 4150 error = task_has_perm(current, p, PROCESS__SETEXEC); 4151 else if (!strcmp(name, "fscreate")) 4152 error = task_has_perm(current, p, PROCESS__SETFSCREATE); 4153 else if (!strcmp(name, "current")) 4154 error = task_has_perm(current, p, PROCESS__SETCURRENT); 4155 else 4156 error = -EINVAL; 4157 if (error) 4158 return error; 4159 4160 /* Obtain a SID for the context, if one was specified. */ 4161 if (size && str[1] && str[1] != '\n') { 4162 if (str[size-1] == '\n') { 4163 str[size-1] = 0; 4164 size--; 4165 } 4166 error = security_context_to_sid(value, size, &sid); 4167 if (error) 4168 return error; 4169 } 4170 4171 /* Permission checking based on the specified context is 4172 performed during the actual operation (execve, 4173 open/mkdir/...), when we know the full context of the 4174 operation. See selinux_bprm_set_security for the execve 4175 checks and may_create for the file creation checks. The 4176 operation will then fail if the context is not permitted. */ 4177 tsec = p->security; 4178 if (!strcmp(name, "exec")) 4179 tsec->exec_sid = sid; 4180 else if (!strcmp(name, "fscreate")) 4181 tsec->create_sid = sid; 4182 else if (!strcmp(name, "current")) { 4183 struct av_decision avd; 4184 4185 if (sid == 0) 4186 return -EINVAL; 4187 4188 /* Only allow single threaded processes to change context */ 4189 if (atomic_read(&p->mm->mm_users) != 1) { 4190 struct task_struct *g, *t; 4191 struct mm_struct *mm = p->mm; 4192 read_lock(&tasklist_lock); 4193 do_each_thread(g, t) 4194 if (t->mm == mm && t != p) { 4195 read_unlock(&tasklist_lock); 4196 return -EPERM; 4197 } 4198 while_each_thread(g, t); 4199 read_unlock(&tasklist_lock); 4200 } 4201 4202 /* Check permissions for the transition. */ 4203 error = avc_has_perm(tsec->sid, sid, SECCLASS_PROCESS, 4204 PROCESS__DYNTRANSITION, NULL); 4205 if (error) 4206 return error; 4207 4208 /* Check for ptracing, and update the task SID if ok. 4209 Otherwise, leave SID unchanged and fail. */ 4210 task_lock(p); 4211 if (p->ptrace & PT_PTRACED) { 4212 error = avc_has_perm_noaudit(tsec->ptrace_sid, sid, 4213 SECCLASS_PROCESS, 4214 PROCESS__PTRACE, &avd); 4215 if (!error) 4216 tsec->sid = sid; 4217 task_unlock(p); 4218 avc_audit(tsec->ptrace_sid, sid, SECCLASS_PROCESS, 4219 PROCESS__PTRACE, &avd, error, NULL); 4220 if (error) 4221 return error; 4222 } else { 4223 tsec->sid = sid; 4224 task_unlock(p); 4225 } 4226 } 4227 else 4228 return -EINVAL; 4229 4230 return size; 4231 } 4232 4233 static struct security_operations selinux_ops = { 4234 .ptrace = selinux_ptrace, 4235 .capget = selinux_capget, 4236 .capset_check = selinux_capset_check, 4237 .capset_set = selinux_capset_set, 4238 .sysctl = selinux_sysctl, 4239 .capable = selinux_capable, 4240 .quotactl = selinux_quotactl, 4241 .quota_on = selinux_quota_on, 4242 .syslog = selinux_syslog, 4243 .vm_enough_memory = selinux_vm_enough_memory, 4244 4245 .netlink_send = selinux_netlink_send, 4246 .netlink_recv = selinux_netlink_recv, 4247 4248 .bprm_alloc_security = selinux_bprm_alloc_security, 4249 .bprm_free_security = selinux_bprm_free_security, 4250 .bprm_apply_creds = selinux_bprm_apply_creds, 4251 .bprm_post_apply_creds = selinux_bprm_post_apply_creds, 4252 .bprm_set_security = selinux_bprm_set_security, 4253 .bprm_check_security = selinux_bprm_check_security, 4254 .bprm_secureexec = selinux_bprm_secureexec, 4255 4256 .sb_alloc_security = selinux_sb_alloc_security, 4257 .sb_free_security = selinux_sb_free_security, 4258 .sb_copy_data = selinux_sb_copy_data, 4259 .sb_kern_mount = selinux_sb_kern_mount, 4260 .sb_statfs = selinux_sb_statfs, 4261 .sb_mount = selinux_mount, 4262 .sb_umount = selinux_umount, 4263 4264 .inode_alloc_security = selinux_inode_alloc_security, 4265 .inode_free_security = selinux_inode_free_security, 4266 .inode_init_security = selinux_inode_init_security, 4267 .inode_create = selinux_inode_create, 4268 .inode_link = selinux_inode_link, 4269 .inode_unlink = selinux_inode_unlink, 4270 .inode_symlink = selinux_inode_symlink, 4271 .inode_mkdir = selinux_inode_mkdir, 4272 .inode_rmdir = selinux_inode_rmdir, 4273 .inode_mknod = selinux_inode_mknod, 4274 .inode_rename = selinux_inode_rename, 4275 .inode_readlink = selinux_inode_readlink, 4276 .inode_follow_link = selinux_inode_follow_link, 4277 .inode_permission = selinux_inode_permission, 4278 .inode_setattr = selinux_inode_setattr, 4279 .inode_getattr = selinux_inode_getattr, 4280 .inode_setxattr = selinux_inode_setxattr, 4281 .inode_post_setxattr = selinux_inode_post_setxattr, 4282 .inode_getxattr = selinux_inode_getxattr, 4283 .inode_listxattr = selinux_inode_listxattr, 4284 .inode_removexattr = selinux_inode_removexattr, 4285 .inode_getsecurity = selinux_inode_getsecurity, 4286 .inode_setsecurity = selinux_inode_setsecurity, 4287 .inode_listsecurity = selinux_inode_listsecurity, 4288 4289 .file_permission = selinux_file_permission, 4290 .file_alloc_security = selinux_file_alloc_security, 4291 .file_free_security = selinux_file_free_security, 4292 .file_ioctl = selinux_file_ioctl, 4293 .file_mmap = selinux_file_mmap, 4294 .file_mprotect = selinux_file_mprotect, 4295 .file_lock = selinux_file_lock, 4296 .file_fcntl = selinux_file_fcntl, 4297 .file_set_fowner = selinux_file_set_fowner, 4298 .file_send_sigiotask = selinux_file_send_sigiotask, 4299 .file_receive = selinux_file_receive, 4300 4301 .task_create = selinux_task_create, 4302 .task_alloc_security = selinux_task_alloc_security, 4303 .task_free_security = selinux_task_free_security, 4304 .task_setuid = selinux_task_setuid, 4305 .task_post_setuid = selinux_task_post_setuid, 4306 .task_setgid = selinux_task_setgid, 4307 .task_setpgid = selinux_task_setpgid, 4308 .task_getpgid = selinux_task_getpgid, 4309 .task_getsid = selinux_task_getsid, 4310 .task_setgroups = selinux_task_setgroups, 4311 .task_setnice = selinux_task_setnice, 4312 .task_setrlimit = selinux_task_setrlimit, 4313 .task_setscheduler = selinux_task_setscheduler, 4314 .task_getscheduler = selinux_task_getscheduler, 4315 .task_kill = selinux_task_kill, 4316 .task_wait = selinux_task_wait, 4317 .task_prctl = selinux_task_prctl, 4318 .task_reparent_to_init = selinux_task_reparent_to_init, 4319 .task_to_inode = selinux_task_to_inode, 4320 4321 .ipc_permission = selinux_ipc_permission, 4322 4323 .msg_msg_alloc_security = selinux_msg_msg_alloc_security, 4324 .msg_msg_free_security = selinux_msg_msg_free_security, 4325 4326 .msg_queue_alloc_security = selinux_msg_queue_alloc_security, 4327 .msg_queue_free_security = selinux_msg_queue_free_security, 4328 .msg_queue_associate = selinux_msg_queue_associate, 4329 .msg_queue_msgctl = selinux_msg_queue_msgctl, 4330 .msg_queue_msgsnd = selinux_msg_queue_msgsnd, 4331 .msg_queue_msgrcv = selinux_msg_queue_msgrcv, 4332 4333 .shm_alloc_security = selinux_shm_alloc_security, 4334 .shm_free_security = selinux_shm_free_security, 4335 .shm_associate = selinux_shm_associate, 4336 .shm_shmctl = selinux_shm_shmctl, 4337 .shm_shmat = selinux_shm_shmat, 4338 4339 .sem_alloc_security = selinux_sem_alloc_security, 4340 .sem_free_security = selinux_sem_free_security, 4341 .sem_associate = selinux_sem_associate, 4342 .sem_semctl = selinux_sem_semctl, 4343 .sem_semop = selinux_sem_semop, 4344 4345 .register_security = selinux_register_security, 4346 .unregister_security = selinux_unregister_security, 4347 4348 .d_instantiate = selinux_d_instantiate, 4349 4350 .getprocattr = selinux_getprocattr, 4351 .setprocattr = selinux_setprocattr, 4352 4353 #ifdef CONFIG_SECURITY_NETWORK 4354 .unix_stream_connect = selinux_socket_unix_stream_connect, 4355 .unix_may_send = selinux_socket_unix_may_send, 4356 4357 .socket_create = selinux_socket_create, 4358 .socket_post_create = selinux_socket_post_create, 4359 .socket_bind = selinux_socket_bind, 4360 .socket_connect = selinux_socket_connect, 4361 .socket_listen = selinux_socket_listen, 4362 .socket_accept = selinux_socket_accept, 4363 .socket_sendmsg = selinux_socket_sendmsg, 4364 .socket_recvmsg = selinux_socket_recvmsg, 4365 .socket_getsockname = selinux_socket_getsockname, 4366 .socket_getpeername = selinux_socket_getpeername, 4367 .socket_getsockopt = selinux_socket_getsockopt, 4368 .socket_setsockopt = selinux_socket_setsockopt, 4369 .socket_shutdown = selinux_socket_shutdown, 4370 .socket_sock_rcv_skb = selinux_socket_sock_rcv_skb, 4371 .socket_getpeersec = selinux_socket_getpeersec, 4372 .sk_alloc_security = selinux_sk_alloc_security, 4373 .sk_free_security = selinux_sk_free_security, 4374 #endif 4375 }; 4376 4377 static __init int selinux_init(void) 4378 { 4379 struct task_security_struct *tsec; 4380 4381 if (!selinux_enabled) { 4382 printk(KERN_INFO "SELinux: Disabled at boot.\n"); 4383 return 0; 4384 } 4385 4386 printk(KERN_INFO "SELinux: Initializing.\n"); 4387 4388 /* Set the security state for the initial task. */ 4389 if (task_alloc_security(current)) 4390 panic("SELinux: Failed to initialize initial task.\n"); 4391 tsec = current->security; 4392 tsec->osid = tsec->sid = SECINITSID_KERNEL; 4393 4394 avc_init(); 4395 4396 original_ops = secondary_ops = security_ops; 4397 if (!secondary_ops) 4398 panic ("SELinux: No initial security operations\n"); 4399 if (register_security (&selinux_ops)) 4400 panic("SELinux: Unable to register with kernel.\n"); 4401 4402 if (selinux_enforcing) { 4403 printk(KERN_INFO "SELinux: Starting in enforcing mode\n"); 4404 } else { 4405 printk(KERN_INFO "SELinux: Starting in permissive mode\n"); 4406 } 4407 return 0; 4408 } 4409 4410 void selinux_complete_init(void) 4411 { 4412 printk(KERN_INFO "SELinux: Completing initialization.\n"); 4413 4414 /* Set up any superblocks initialized prior to the policy load. */ 4415 printk(KERN_INFO "SELinux: Setting up existing superblocks.\n"); 4416 spin_lock(&sb_security_lock); 4417 next_sb: 4418 if (!list_empty(&superblock_security_head)) { 4419 struct superblock_security_struct *sbsec = 4420 list_entry(superblock_security_head.next, 4421 struct superblock_security_struct, 4422 list); 4423 struct super_block *sb = sbsec->sb; 4424 spin_lock(&sb_lock); 4425 sb->s_count++; 4426 spin_unlock(&sb_lock); 4427 spin_unlock(&sb_security_lock); 4428 down_read(&sb->s_umount); 4429 if (sb->s_root) 4430 superblock_doinit(sb, NULL); 4431 drop_super(sb); 4432 spin_lock(&sb_security_lock); 4433 list_del_init(&sbsec->list); 4434 goto next_sb; 4435 } 4436 spin_unlock(&sb_security_lock); 4437 } 4438 4439 /* SELinux requires early initialization in order to label 4440 all processes and objects when they are created. */ 4441 security_initcall(selinux_init); 4442 4443 #if defined(CONFIG_SECURITY_NETWORK) && defined(CONFIG_NETFILTER) 4444 4445 static struct nf_hook_ops selinux_ipv4_op = { 4446 .hook = selinux_ipv4_postroute_last, 4447 .owner = THIS_MODULE, 4448 .pf = PF_INET, 4449 .hooknum = NF_IP_POST_ROUTING, 4450 .priority = NF_IP_PRI_SELINUX_LAST, 4451 }; 4452 4453 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE) 4454 4455 static struct nf_hook_ops selinux_ipv6_op = { 4456 .hook = selinux_ipv6_postroute_last, 4457 .owner = THIS_MODULE, 4458 .pf = PF_INET6, 4459 .hooknum = NF_IP6_POST_ROUTING, 4460 .priority = NF_IP6_PRI_SELINUX_LAST, 4461 }; 4462 4463 #endif /* IPV6 */ 4464 4465 static int __init selinux_nf_ip_init(void) 4466 { 4467 int err = 0; 4468 4469 if (!selinux_enabled) 4470 goto out; 4471 4472 printk(KERN_INFO "SELinux: Registering netfilter hooks\n"); 4473 4474 err = nf_register_hook(&selinux_ipv4_op); 4475 if (err) 4476 panic("SELinux: nf_register_hook for IPv4: error %d\n", err); 4477 4478 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE) 4479 4480 err = nf_register_hook(&selinux_ipv6_op); 4481 if (err) 4482 panic("SELinux: nf_register_hook for IPv6: error %d\n", err); 4483 4484 #endif /* IPV6 */ 4485 out: 4486 return err; 4487 } 4488 4489 __initcall(selinux_nf_ip_init); 4490 4491 #ifdef CONFIG_SECURITY_SELINUX_DISABLE 4492 static void selinux_nf_ip_exit(void) 4493 { 4494 printk(KERN_INFO "SELinux: Unregistering netfilter hooks\n"); 4495 4496 nf_unregister_hook(&selinux_ipv4_op); 4497 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE) 4498 nf_unregister_hook(&selinux_ipv6_op); 4499 #endif /* IPV6 */ 4500 } 4501 #endif 4502 4503 #else /* CONFIG_SECURITY_NETWORK && CONFIG_NETFILTER */ 4504 4505 #ifdef CONFIG_SECURITY_SELINUX_DISABLE 4506 #define selinux_nf_ip_exit() 4507 #endif 4508 4509 #endif /* CONFIG_SECURITY_NETWORK && CONFIG_NETFILTER */ 4510 4511 #ifdef CONFIG_SECURITY_SELINUX_DISABLE 4512 int selinux_disable(void) 4513 { 4514 extern void exit_sel_fs(void); 4515 static int selinux_disabled = 0; 4516 4517 if (ss_initialized) { 4518 /* Not permitted after initial policy load. */ 4519 return -EINVAL; 4520 } 4521 4522 if (selinux_disabled) { 4523 /* Only do this once. */ 4524 return -EINVAL; 4525 } 4526 4527 printk(KERN_INFO "SELinux: Disabled at runtime.\n"); 4528 4529 selinux_disabled = 1; 4530 4531 /* Reset security_ops to the secondary module, dummy or capability. */ 4532 security_ops = secondary_ops; 4533 4534 /* Unregister netfilter hooks. */ 4535 selinux_nf_ip_exit(); 4536 4537 /* Unregister selinuxfs. */ 4538 exit_sel_fs(); 4539 4540 return 0; 4541 } 4542 #endif 4543 4544 4545