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) 2003-2008 Red Hat, Inc., James Morris <jmorris@redhat.com> 13 * Eric Paris <eparis@redhat.com> 14 * Copyright (C) 2004-2005 Trusted Computer Solutions, Inc. 15 * <dgoeddel@trustedcs.com> 16 * Copyright (C) 2006, 2007 Hewlett-Packard Development Company, L.P. 17 * Paul Moore <paul.moore@hp.com> 18 * Copyright (C) 2007 Hitachi Software Engineering Co., Ltd. 19 * Yuichi Nakamura <ynakam@hitachisoft.jp> 20 * 21 * This program is free software; you can redistribute it and/or modify 22 * it under the terms of the GNU General Public License version 2, 23 * as published by the Free Software Foundation. 24 */ 25 26 #include <linux/init.h> 27 #include <linux/kernel.h> 28 #include <linux/tracehook.h> 29 #include <linux/errno.h> 30 #include <linux/sched.h> 31 #include <linux/security.h> 32 #include <linux/xattr.h> 33 #include <linux/capability.h> 34 #include <linux/unistd.h> 35 #include <linux/mm.h> 36 #include <linux/mman.h> 37 #include <linux/slab.h> 38 #include <linux/pagemap.h> 39 #include <linux/swap.h> 40 #include <linux/spinlock.h> 41 #include <linux/syscalls.h> 42 #include <linux/file.h> 43 #include <linux/fdtable.h> 44 #include <linux/namei.h> 45 #include <linux/mount.h> 46 #include <linux/proc_fs.h> 47 #include <linux/netfilter_ipv4.h> 48 #include <linux/netfilter_ipv6.h> 49 #include <linux/tty.h> 50 #include <net/icmp.h> 51 #include <net/ip.h> /* for local_port_range[] */ 52 #include <net/tcp.h> /* struct or_callable used in sock_rcv_skb */ 53 #include <net/net_namespace.h> 54 #include <net/netlabel.h> 55 #include <linux/uaccess.h> 56 #include <asm/ioctls.h> 57 #include <asm/atomic.h> 58 #include <linux/bitops.h> 59 #include <linux/interrupt.h> 60 #include <linux/netdevice.h> /* for network interface checks */ 61 #include <linux/netlink.h> 62 #include <linux/tcp.h> 63 #include <linux/udp.h> 64 #include <linux/dccp.h> 65 #include <linux/quota.h> 66 #include <linux/un.h> /* for Unix socket types */ 67 #include <net/af_unix.h> /* for Unix socket types */ 68 #include <linux/parser.h> 69 #include <linux/nfs_mount.h> 70 #include <net/ipv6.h> 71 #include <linux/hugetlb.h> 72 #include <linux/personality.h> 73 #include <linux/sysctl.h> 74 #include <linux/audit.h> 75 #include <linux/string.h> 76 #include <linux/selinux.h> 77 #include <linux/mutex.h> 78 #include <linux/posix-timers.h> 79 80 #include "avc.h" 81 #include "objsec.h" 82 #include "netif.h" 83 #include "netnode.h" 84 #include "netport.h" 85 #include "xfrm.h" 86 #include "netlabel.h" 87 #include "audit.h" 88 89 #define XATTR_SELINUX_SUFFIX "selinux" 90 #define XATTR_NAME_SELINUX XATTR_SECURITY_PREFIX XATTR_SELINUX_SUFFIX 91 92 #define NUM_SEL_MNT_OPTS 5 93 94 extern unsigned int policydb_loaded_version; 95 extern int selinux_nlmsg_lookup(u16 sclass, u16 nlmsg_type, u32 *perm); 96 extern int selinux_compat_net; 97 extern struct security_operations *security_ops; 98 99 /* SECMARK reference count */ 100 atomic_t selinux_secmark_refcount = ATOMIC_INIT(0); 101 102 #ifdef CONFIG_SECURITY_SELINUX_DEVELOP 103 int selinux_enforcing; 104 105 static int __init enforcing_setup(char *str) 106 { 107 unsigned long enforcing; 108 if (!strict_strtoul(str, 0, &enforcing)) 109 selinux_enforcing = enforcing ? 1 : 0; 110 return 1; 111 } 112 __setup("enforcing=", enforcing_setup); 113 #endif 114 115 #ifdef CONFIG_SECURITY_SELINUX_BOOTPARAM 116 int selinux_enabled = CONFIG_SECURITY_SELINUX_BOOTPARAM_VALUE; 117 118 static int __init selinux_enabled_setup(char *str) 119 { 120 unsigned long enabled; 121 if (!strict_strtoul(str, 0, &enabled)) 122 selinux_enabled = enabled ? 1 : 0; 123 return 1; 124 } 125 __setup("selinux=", selinux_enabled_setup); 126 #else 127 int selinux_enabled = 1; 128 #endif 129 130 131 /* 132 * Minimal support for a secondary security module, 133 * just to allow the use of the capability module. 134 */ 135 static struct security_operations *secondary_ops; 136 137 /* Lists of inode and superblock security structures initialized 138 before the policy was loaded. */ 139 static LIST_HEAD(superblock_security_head); 140 static DEFINE_SPINLOCK(sb_security_lock); 141 142 static struct kmem_cache *sel_inode_cache; 143 144 /** 145 * selinux_secmark_enabled - Check to see if SECMARK is currently enabled 146 * 147 * Description: 148 * This function checks the SECMARK reference counter to see if any SECMARK 149 * targets are currently configured, if the reference counter is greater than 150 * zero SECMARK is considered to be enabled. Returns true (1) if SECMARK is 151 * enabled, false (0) if SECMARK is disabled. 152 * 153 */ 154 static int selinux_secmark_enabled(void) 155 { 156 return (atomic_read(&selinux_secmark_refcount) > 0); 157 } 158 159 /* 160 * initialise the security for the init task 161 */ 162 static void cred_init_security(void) 163 { 164 struct cred *cred = (struct cred *) current->real_cred; 165 struct task_security_struct *tsec; 166 167 tsec = kzalloc(sizeof(struct task_security_struct), GFP_KERNEL); 168 if (!tsec) 169 panic("SELinux: Failed to initialize initial task.\n"); 170 171 tsec->osid = tsec->sid = SECINITSID_KERNEL; 172 cred->security = tsec; 173 } 174 175 /* 176 * get the security ID of a set of credentials 177 */ 178 static inline u32 cred_sid(const struct cred *cred) 179 { 180 const struct task_security_struct *tsec; 181 182 tsec = cred->security; 183 return tsec->sid; 184 } 185 186 /* 187 * get the objective security ID of a task 188 */ 189 static inline u32 task_sid(const struct task_struct *task) 190 { 191 u32 sid; 192 193 rcu_read_lock(); 194 sid = cred_sid(__task_cred(task)); 195 rcu_read_unlock(); 196 return sid; 197 } 198 199 /* 200 * get the subjective security ID of the current task 201 */ 202 static inline u32 current_sid(void) 203 { 204 const struct task_security_struct *tsec = current_cred()->security; 205 206 return tsec->sid; 207 } 208 209 /* Allocate and free functions for each kind of security blob. */ 210 211 static int inode_alloc_security(struct inode *inode) 212 { 213 struct inode_security_struct *isec; 214 u32 sid = current_sid(); 215 216 isec = kmem_cache_zalloc(sel_inode_cache, GFP_NOFS); 217 if (!isec) 218 return -ENOMEM; 219 220 mutex_init(&isec->lock); 221 INIT_LIST_HEAD(&isec->list); 222 isec->inode = inode; 223 isec->sid = SECINITSID_UNLABELED; 224 isec->sclass = SECCLASS_FILE; 225 isec->task_sid = sid; 226 inode->i_security = isec; 227 228 return 0; 229 } 230 231 static void inode_free_security(struct inode *inode) 232 { 233 struct inode_security_struct *isec = inode->i_security; 234 struct superblock_security_struct *sbsec = inode->i_sb->s_security; 235 236 spin_lock(&sbsec->isec_lock); 237 if (!list_empty(&isec->list)) 238 list_del_init(&isec->list); 239 spin_unlock(&sbsec->isec_lock); 240 241 inode->i_security = NULL; 242 kmem_cache_free(sel_inode_cache, isec); 243 } 244 245 static int file_alloc_security(struct file *file) 246 { 247 struct file_security_struct *fsec; 248 u32 sid = current_sid(); 249 250 fsec = kzalloc(sizeof(struct file_security_struct), GFP_KERNEL); 251 if (!fsec) 252 return -ENOMEM; 253 254 fsec->sid = sid; 255 fsec->fown_sid = sid; 256 file->f_security = fsec; 257 258 return 0; 259 } 260 261 static void file_free_security(struct file *file) 262 { 263 struct file_security_struct *fsec = file->f_security; 264 file->f_security = NULL; 265 kfree(fsec); 266 } 267 268 static int superblock_alloc_security(struct super_block *sb) 269 { 270 struct superblock_security_struct *sbsec; 271 272 sbsec = kzalloc(sizeof(struct superblock_security_struct), GFP_KERNEL); 273 if (!sbsec) 274 return -ENOMEM; 275 276 mutex_init(&sbsec->lock); 277 INIT_LIST_HEAD(&sbsec->list); 278 INIT_LIST_HEAD(&sbsec->isec_head); 279 spin_lock_init(&sbsec->isec_lock); 280 sbsec->sb = sb; 281 sbsec->sid = SECINITSID_UNLABELED; 282 sbsec->def_sid = SECINITSID_FILE; 283 sbsec->mntpoint_sid = SECINITSID_UNLABELED; 284 sb->s_security = sbsec; 285 286 return 0; 287 } 288 289 static void superblock_free_security(struct super_block *sb) 290 { 291 struct superblock_security_struct *sbsec = sb->s_security; 292 293 spin_lock(&sb_security_lock); 294 if (!list_empty(&sbsec->list)) 295 list_del_init(&sbsec->list); 296 spin_unlock(&sb_security_lock); 297 298 sb->s_security = NULL; 299 kfree(sbsec); 300 } 301 302 static int sk_alloc_security(struct sock *sk, int family, gfp_t priority) 303 { 304 struct sk_security_struct *ssec; 305 306 ssec = kzalloc(sizeof(*ssec), priority); 307 if (!ssec) 308 return -ENOMEM; 309 310 ssec->peer_sid = SECINITSID_UNLABELED; 311 ssec->sid = SECINITSID_UNLABELED; 312 sk->sk_security = ssec; 313 314 selinux_netlbl_sk_security_reset(ssec, family); 315 316 return 0; 317 } 318 319 static void sk_free_security(struct sock *sk) 320 { 321 struct sk_security_struct *ssec = sk->sk_security; 322 323 sk->sk_security = NULL; 324 selinux_netlbl_sk_security_free(ssec); 325 kfree(ssec); 326 } 327 328 /* The security server must be initialized before 329 any labeling or access decisions can be provided. */ 330 extern int ss_initialized; 331 332 /* The file system's label must be initialized prior to use. */ 333 334 static char *labeling_behaviors[6] = { 335 "uses xattr", 336 "uses transition SIDs", 337 "uses task SIDs", 338 "uses genfs_contexts", 339 "not configured for labeling", 340 "uses mountpoint labeling", 341 }; 342 343 static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dentry); 344 345 static inline int inode_doinit(struct inode *inode) 346 { 347 return inode_doinit_with_dentry(inode, NULL); 348 } 349 350 enum { 351 Opt_error = -1, 352 Opt_context = 1, 353 Opt_fscontext = 2, 354 Opt_defcontext = 3, 355 Opt_rootcontext = 4, 356 Opt_labelsupport = 5, 357 }; 358 359 static const match_table_t tokens = { 360 {Opt_context, CONTEXT_STR "%s"}, 361 {Opt_fscontext, FSCONTEXT_STR "%s"}, 362 {Opt_defcontext, DEFCONTEXT_STR "%s"}, 363 {Opt_rootcontext, ROOTCONTEXT_STR "%s"}, 364 {Opt_labelsupport, LABELSUPP_STR}, 365 {Opt_error, NULL}, 366 }; 367 368 #define SEL_MOUNT_FAIL_MSG "SELinux: duplicate or incompatible mount options\n" 369 370 static int may_context_mount_sb_relabel(u32 sid, 371 struct superblock_security_struct *sbsec, 372 const struct cred *cred) 373 { 374 const struct task_security_struct *tsec = cred->security; 375 int rc; 376 377 rc = avc_has_perm(tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM, 378 FILESYSTEM__RELABELFROM, NULL); 379 if (rc) 380 return rc; 381 382 rc = avc_has_perm(tsec->sid, sid, SECCLASS_FILESYSTEM, 383 FILESYSTEM__RELABELTO, NULL); 384 return rc; 385 } 386 387 static int may_context_mount_inode_relabel(u32 sid, 388 struct superblock_security_struct *sbsec, 389 const struct cred *cred) 390 { 391 const struct task_security_struct *tsec = cred->security; 392 int rc; 393 rc = avc_has_perm(tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM, 394 FILESYSTEM__RELABELFROM, NULL); 395 if (rc) 396 return rc; 397 398 rc = avc_has_perm(sid, sbsec->sid, SECCLASS_FILESYSTEM, 399 FILESYSTEM__ASSOCIATE, NULL); 400 return rc; 401 } 402 403 static int sb_finish_set_opts(struct super_block *sb) 404 { 405 struct superblock_security_struct *sbsec = sb->s_security; 406 struct dentry *root = sb->s_root; 407 struct inode *root_inode = root->d_inode; 408 int rc = 0; 409 410 if (sbsec->behavior == SECURITY_FS_USE_XATTR) { 411 /* Make sure that the xattr handler exists and that no 412 error other than -ENODATA is returned by getxattr on 413 the root directory. -ENODATA is ok, as this may be 414 the first boot of the SELinux kernel before we have 415 assigned xattr values to the filesystem. */ 416 if (!root_inode->i_op->getxattr) { 417 printk(KERN_WARNING "SELinux: (dev %s, type %s) has no " 418 "xattr support\n", sb->s_id, sb->s_type->name); 419 rc = -EOPNOTSUPP; 420 goto out; 421 } 422 rc = root_inode->i_op->getxattr(root, XATTR_NAME_SELINUX, NULL, 0); 423 if (rc < 0 && rc != -ENODATA) { 424 if (rc == -EOPNOTSUPP) 425 printk(KERN_WARNING "SELinux: (dev %s, type " 426 "%s) has no security xattr handler\n", 427 sb->s_id, sb->s_type->name); 428 else 429 printk(KERN_WARNING "SELinux: (dev %s, type " 430 "%s) getxattr errno %d\n", sb->s_id, 431 sb->s_type->name, -rc); 432 goto out; 433 } 434 } 435 436 sbsec->flags |= (SE_SBINITIALIZED | SE_SBLABELSUPP); 437 438 if (sbsec->behavior > ARRAY_SIZE(labeling_behaviors)) 439 printk(KERN_ERR "SELinux: initialized (dev %s, type %s), unknown behavior\n", 440 sb->s_id, sb->s_type->name); 441 else 442 printk(KERN_DEBUG "SELinux: initialized (dev %s, type %s), %s\n", 443 sb->s_id, sb->s_type->name, 444 labeling_behaviors[sbsec->behavior-1]); 445 446 if (sbsec->behavior == SECURITY_FS_USE_GENFS || 447 sbsec->behavior == SECURITY_FS_USE_MNTPOINT || 448 sbsec->behavior == SECURITY_FS_USE_NONE || 449 sbsec->behavior > ARRAY_SIZE(labeling_behaviors)) 450 sbsec->flags &= ~SE_SBLABELSUPP; 451 452 /* Initialize the root inode. */ 453 rc = inode_doinit_with_dentry(root_inode, root); 454 455 /* Initialize any other inodes associated with the superblock, e.g. 456 inodes created prior to initial policy load or inodes created 457 during get_sb by a pseudo filesystem that directly 458 populates itself. */ 459 spin_lock(&sbsec->isec_lock); 460 next_inode: 461 if (!list_empty(&sbsec->isec_head)) { 462 struct inode_security_struct *isec = 463 list_entry(sbsec->isec_head.next, 464 struct inode_security_struct, list); 465 struct inode *inode = isec->inode; 466 spin_unlock(&sbsec->isec_lock); 467 inode = igrab(inode); 468 if (inode) { 469 if (!IS_PRIVATE(inode)) 470 inode_doinit(inode); 471 iput(inode); 472 } 473 spin_lock(&sbsec->isec_lock); 474 list_del_init(&isec->list); 475 goto next_inode; 476 } 477 spin_unlock(&sbsec->isec_lock); 478 out: 479 return rc; 480 } 481 482 /* 483 * This function should allow an FS to ask what it's mount security 484 * options were so it can use those later for submounts, displaying 485 * mount options, or whatever. 486 */ 487 static int selinux_get_mnt_opts(const struct super_block *sb, 488 struct security_mnt_opts *opts) 489 { 490 int rc = 0, i; 491 struct superblock_security_struct *sbsec = sb->s_security; 492 char *context = NULL; 493 u32 len; 494 char tmp; 495 496 security_init_mnt_opts(opts); 497 498 if (!(sbsec->flags & SE_SBINITIALIZED)) 499 return -EINVAL; 500 501 if (!ss_initialized) 502 return -EINVAL; 503 504 tmp = sbsec->flags & SE_MNTMASK; 505 /* count the number of mount options for this sb */ 506 for (i = 0; i < 8; i++) { 507 if (tmp & 0x01) 508 opts->num_mnt_opts++; 509 tmp >>= 1; 510 } 511 /* Check if the Label support flag is set */ 512 if (sbsec->flags & SE_SBLABELSUPP) 513 opts->num_mnt_opts++; 514 515 opts->mnt_opts = kcalloc(opts->num_mnt_opts, sizeof(char *), GFP_ATOMIC); 516 if (!opts->mnt_opts) { 517 rc = -ENOMEM; 518 goto out_free; 519 } 520 521 opts->mnt_opts_flags = kcalloc(opts->num_mnt_opts, sizeof(int), GFP_ATOMIC); 522 if (!opts->mnt_opts_flags) { 523 rc = -ENOMEM; 524 goto out_free; 525 } 526 527 i = 0; 528 if (sbsec->flags & FSCONTEXT_MNT) { 529 rc = security_sid_to_context(sbsec->sid, &context, &len); 530 if (rc) 531 goto out_free; 532 opts->mnt_opts[i] = context; 533 opts->mnt_opts_flags[i++] = FSCONTEXT_MNT; 534 } 535 if (sbsec->flags & CONTEXT_MNT) { 536 rc = security_sid_to_context(sbsec->mntpoint_sid, &context, &len); 537 if (rc) 538 goto out_free; 539 opts->mnt_opts[i] = context; 540 opts->mnt_opts_flags[i++] = CONTEXT_MNT; 541 } 542 if (sbsec->flags & DEFCONTEXT_MNT) { 543 rc = security_sid_to_context(sbsec->def_sid, &context, &len); 544 if (rc) 545 goto out_free; 546 opts->mnt_opts[i] = context; 547 opts->mnt_opts_flags[i++] = DEFCONTEXT_MNT; 548 } 549 if (sbsec->flags & ROOTCONTEXT_MNT) { 550 struct inode *root = sbsec->sb->s_root->d_inode; 551 struct inode_security_struct *isec = root->i_security; 552 553 rc = security_sid_to_context(isec->sid, &context, &len); 554 if (rc) 555 goto out_free; 556 opts->mnt_opts[i] = context; 557 opts->mnt_opts_flags[i++] = ROOTCONTEXT_MNT; 558 } 559 if (sbsec->flags & SE_SBLABELSUPP) { 560 opts->mnt_opts[i] = NULL; 561 opts->mnt_opts_flags[i++] = SE_SBLABELSUPP; 562 } 563 564 BUG_ON(i != opts->num_mnt_opts); 565 566 return 0; 567 568 out_free: 569 security_free_mnt_opts(opts); 570 return rc; 571 } 572 573 static int bad_option(struct superblock_security_struct *sbsec, char flag, 574 u32 old_sid, u32 new_sid) 575 { 576 char mnt_flags = sbsec->flags & SE_MNTMASK; 577 578 /* check if the old mount command had the same options */ 579 if (sbsec->flags & SE_SBINITIALIZED) 580 if (!(sbsec->flags & flag) || 581 (old_sid != new_sid)) 582 return 1; 583 584 /* check if we were passed the same options twice, 585 * aka someone passed context=a,context=b 586 */ 587 if (!(sbsec->flags & SE_SBINITIALIZED)) 588 if (mnt_flags & flag) 589 return 1; 590 return 0; 591 } 592 593 /* 594 * Allow filesystems with binary mount data to explicitly set mount point 595 * labeling information. 596 */ 597 static int selinux_set_mnt_opts(struct super_block *sb, 598 struct security_mnt_opts *opts) 599 { 600 const struct cred *cred = current_cred(); 601 int rc = 0, i; 602 struct superblock_security_struct *sbsec = sb->s_security; 603 const char *name = sb->s_type->name; 604 struct inode *inode = sbsec->sb->s_root->d_inode; 605 struct inode_security_struct *root_isec = inode->i_security; 606 u32 fscontext_sid = 0, context_sid = 0, rootcontext_sid = 0; 607 u32 defcontext_sid = 0; 608 char **mount_options = opts->mnt_opts; 609 int *flags = opts->mnt_opts_flags; 610 int num_opts = opts->num_mnt_opts; 611 612 mutex_lock(&sbsec->lock); 613 614 if (!ss_initialized) { 615 if (!num_opts) { 616 /* Defer initialization until selinux_complete_init, 617 after the initial policy is loaded and the security 618 server is ready to handle calls. */ 619 spin_lock(&sb_security_lock); 620 if (list_empty(&sbsec->list)) 621 list_add(&sbsec->list, &superblock_security_head); 622 spin_unlock(&sb_security_lock); 623 goto out; 624 } 625 rc = -EINVAL; 626 printk(KERN_WARNING "SELinux: Unable to set superblock options " 627 "before the security server is initialized\n"); 628 goto out; 629 } 630 631 /* 632 * Binary mount data FS will come through this function twice. Once 633 * from an explicit call and once from the generic calls from the vfs. 634 * Since the generic VFS calls will not contain any security mount data 635 * we need to skip the double mount verification. 636 * 637 * This does open a hole in which we will not notice if the first 638 * mount using this sb set explict options and a second mount using 639 * this sb does not set any security options. (The first options 640 * will be used for both mounts) 641 */ 642 if ((sbsec->flags & SE_SBINITIALIZED) && (sb->s_type->fs_flags & FS_BINARY_MOUNTDATA) 643 && (num_opts == 0)) 644 goto out; 645 646 /* 647 * parse the mount options, check if they are valid sids. 648 * also check if someone is trying to mount the same sb more 649 * than once with different security options. 650 */ 651 for (i = 0; i < num_opts; i++) { 652 u32 sid; 653 654 if (flags[i] == SE_SBLABELSUPP) 655 continue; 656 rc = security_context_to_sid(mount_options[i], 657 strlen(mount_options[i]), &sid); 658 if (rc) { 659 printk(KERN_WARNING "SELinux: security_context_to_sid" 660 "(%s) failed for (dev %s, type %s) errno=%d\n", 661 mount_options[i], sb->s_id, name, rc); 662 goto out; 663 } 664 switch (flags[i]) { 665 case FSCONTEXT_MNT: 666 fscontext_sid = sid; 667 668 if (bad_option(sbsec, FSCONTEXT_MNT, sbsec->sid, 669 fscontext_sid)) 670 goto out_double_mount; 671 672 sbsec->flags |= FSCONTEXT_MNT; 673 break; 674 case CONTEXT_MNT: 675 context_sid = sid; 676 677 if (bad_option(sbsec, CONTEXT_MNT, sbsec->mntpoint_sid, 678 context_sid)) 679 goto out_double_mount; 680 681 sbsec->flags |= CONTEXT_MNT; 682 break; 683 case ROOTCONTEXT_MNT: 684 rootcontext_sid = sid; 685 686 if (bad_option(sbsec, ROOTCONTEXT_MNT, root_isec->sid, 687 rootcontext_sid)) 688 goto out_double_mount; 689 690 sbsec->flags |= ROOTCONTEXT_MNT; 691 692 break; 693 case DEFCONTEXT_MNT: 694 defcontext_sid = sid; 695 696 if (bad_option(sbsec, DEFCONTEXT_MNT, sbsec->def_sid, 697 defcontext_sid)) 698 goto out_double_mount; 699 700 sbsec->flags |= DEFCONTEXT_MNT; 701 702 break; 703 default: 704 rc = -EINVAL; 705 goto out; 706 } 707 } 708 709 if (sbsec->flags & SE_SBINITIALIZED) { 710 /* previously mounted with options, but not on this attempt? */ 711 if ((sbsec->flags & SE_MNTMASK) && !num_opts) 712 goto out_double_mount; 713 rc = 0; 714 goto out; 715 } 716 717 if (strcmp(sb->s_type->name, "proc") == 0) 718 sbsec->flags |= SE_SBPROC; 719 720 /* Determine the labeling behavior to use for this filesystem type. */ 721 rc = security_fs_use((sbsec->flags & SE_SBPROC) ? "proc" : sb->s_type->name, &sbsec->behavior, &sbsec->sid); 722 if (rc) { 723 printk(KERN_WARNING "%s: security_fs_use(%s) returned %d\n", 724 __func__, sb->s_type->name, rc); 725 goto out; 726 } 727 728 /* sets the context of the superblock for the fs being mounted. */ 729 if (fscontext_sid) { 730 rc = may_context_mount_sb_relabel(fscontext_sid, sbsec, cred); 731 if (rc) 732 goto out; 733 734 sbsec->sid = fscontext_sid; 735 } 736 737 /* 738 * Switch to using mount point labeling behavior. 739 * sets the label used on all file below the mountpoint, and will set 740 * the superblock context if not already set. 741 */ 742 if (context_sid) { 743 if (!fscontext_sid) { 744 rc = may_context_mount_sb_relabel(context_sid, sbsec, 745 cred); 746 if (rc) 747 goto out; 748 sbsec->sid = context_sid; 749 } else { 750 rc = may_context_mount_inode_relabel(context_sid, sbsec, 751 cred); 752 if (rc) 753 goto out; 754 } 755 if (!rootcontext_sid) 756 rootcontext_sid = context_sid; 757 758 sbsec->mntpoint_sid = context_sid; 759 sbsec->behavior = SECURITY_FS_USE_MNTPOINT; 760 } 761 762 if (rootcontext_sid) { 763 rc = may_context_mount_inode_relabel(rootcontext_sid, sbsec, 764 cred); 765 if (rc) 766 goto out; 767 768 root_isec->sid = rootcontext_sid; 769 root_isec->initialized = 1; 770 } 771 772 if (defcontext_sid) { 773 if (sbsec->behavior != SECURITY_FS_USE_XATTR) { 774 rc = -EINVAL; 775 printk(KERN_WARNING "SELinux: defcontext option is " 776 "invalid for this filesystem type\n"); 777 goto out; 778 } 779 780 if (defcontext_sid != sbsec->def_sid) { 781 rc = may_context_mount_inode_relabel(defcontext_sid, 782 sbsec, cred); 783 if (rc) 784 goto out; 785 } 786 787 sbsec->def_sid = defcontext_sid; 788 } 789 790 rc = sb_finish_set_opts(sb); 791 out: 792 mutex_unlock(&sbsec->lock); 793 return rc; 794 out_double_mount: 795 rc = -EINVAL; 796 printk(KERN_WARNING "SELinux: mount invalid. Same superblock, different " 797 "security settings for (dev %s, type %s)\n", sb->s_id, name); 798 goto out; 799 } 800 801 static void selinux_sb_clone_mnt_opts(const struct super_block *oldsb, 802 struct super_block *newsb) 803 { 804 const struct superblock_security_struct *oldsbsec = oldsb->s_security; 805 struct superblock_security_struct *newsbsec = newsb->s_security; 806 807 int set_fscontext = (oldsbsec->flags & FSCONTEXT_MNT); 808 int set_context = (oldsbsec->flags & CONTEXT_MNT); 809 int set_rootcontext = (oldsbsec->flags & ROOTCONTEXT_MNT); 810 811 /* 812 * if the parent was able to be mounted it clearly had no special lsm 813 * mount options. thus we can safely put this sb on the list and deal 814 * with it later 815 */ 816 if (!ss_initialized) { 817 spin_lock(&sb_security_lock); 818 if (list_empty(&newsbsec->list)) 819 list_add(&newsbsec->list, &superblock_security_head); 820 spin_unlock(&sb_security_lock); 821 return; 822 } 823 824 /* how can we clone if the old one wasn't set up?? */ 825 BUG_ON(!(oldsbsec->flags & SE_SBINITIALIZED)); 826 827 /* if fs is reusing a sb, just let its options stand... */ 828 if (newsbsec->flags & SE_SBINITIALIZED) 829 return; 830 831 mutex_lock(&newsbsec->lock); 832 833 newsbsec->flags = oldsbsec->flags; 834 835 newsbsec->sid = oldsbsec->sid; 836 newsbsec->def_sid = oldsbsec->def_sid; 837 newsbsec->behavior = oldsbsec->behavior; 838 839 if (set_context) { 840 u32 sid = oldsbsec->mntpoint_sid; 841 842 if (!set_fscontext) 843 newsbsec->sid = sid; 844 if (!set_rootcontext) { 845 struct inode *newinode = newsb->s_root->d_inode; 846 struct inode_security_struct *newisec = newinode->i_security; 847 newisec->sid = sid; 848 } 849 newsbsec->mntpoint_sid = sid; 850 } 851 if (set_rootcontext) { 852 const struct inode *oldinode = oldsb->s_root->d_inode; 853 const struct inode_security_struct *oldisec = oldinode->i_security; 854 struct inode *newinode = newsb->s_root->d_inode; 855 struct inode_security_struct *newisec = newinode->i_security; 856 857 newisec->sid = oldisec->sid; 858 } 859 860 sb_finish_set_opts(newsb); 861 mutex_unlock(&newsbsec->lock); 862 } 863 864 static int selinux_parse_opts_str(char *options, 865 struct security_mnt_opts *opts) 866 { 867 char *p; 868 char *context = NULL, *defcontext = NULL; 869 char *fscontext = NULL, *rootcontext = NULL; 870 int rc, num_mnt_opts = 0; 871 872 opts->num_mnt_opts = 0; 873 874 /* Standard string-based options. */ 875 while ((p = strsep(&options, "|")) != NULL) { 876 int token; 877 substring_t args[MAX_OPT_ARGS]; 878 879 if (!*p) 880 continue; 881 882 token = match_token(p, tokens, args); 883 884 switch (token) { 885 case Opt_context: 886 if (context || defcontext) { 887 rc = -EINVAL; 888 printk(KERN_WARNING SEL_MOUNT_FAIL_MSG); 889 goto out_err; 890 } 891 context = match_strdup(&args[0]); 892 if (!context) { 893 rc = -ENOMEM; 894 goto out_err; 895 } 896 break; 897 898 case Opt_fscontext: 899 if (fscontext) { 900 rc = -EINVAL; 901 printk(KERN_WARNING SEL_MOUNT_FAIL_MSG); 902 goto out_err; 903 } 904 fscontext = match_strdup(&args[0]); 905 if (!fscontext) { 906 rc = -ENOMEM; 907 goto out_err; 908 } 909 break; 910 911 case Opt_rootcontext: 912 if (rootcontext) { 913 rc = -EINVAL; 914 printk(KERN_WARNING SEL_MOUNT_FAIL_MSG); 915 goto out_err; 916 } 917 rootcontext = match_strdup(&args[0]); 918 if (!rootcontext) { 919 rc = -ENOMEM; 920 goto out_err; 921 } 922 break; 923 924 case Opt_defcontext: 925 if (context || defcontext) { 926 rc = -EINVAL; 927 printk(KERN_WARNING SEL_MOUNT_FAIL_MSG); 928 goto out_err; 929 } 930 defcontext = match_strdup(&args[0]); 931 if (!defcontext) { 932 rc = -ENOMEM; 933 goto out_err; 934 } 935 break; 936 case Opt_labelsupport: 937 break; 938 default: 939 rc = -EINVAL; 940 printk(KERN_WARNING "SELinux: unknown mount option\n"); 941 goto out_err; 942 943 } 944 } 945 946 rc = -ENOMEM; 947 opts->mnt_opts = kcalloc(NUM_SEL_MNT_OPTS, sizeof(char *), GFP_ATOMIC); 948 if (!opts->mnt_opts) 949 goto out_err; 950 951 opts->mnt_opts_flags = kcalloc(NUM_SEL_MNT_OPTS, sizeof(int), GFP_ATOMIC); 952 if (!opts->mnt_opts_flags) { 953 kfree(opts->mnt_opts); 954 goto out_err; 955 } 956 957 if (fscontext) { 958 opts->mnt_opts[num_mnt_opts] = fscontext; 959 opts->mnt_opts_flags[num_mnt_opts++] = FSCONTEXT_MNT; 960 } 961 if (context) { 962 opts->mnt_opts[num_mnt_opts] = context; 963 opts->mnt_opts_flags[num_mnt_opts++] = CONTEXT_MNT; 964 } 965 if (rootcontext) { 966 opts->mnt_opts[num_mnt_opts] = rootcontext; 967 opts->mnt_opts_flags[num_mnt_opts++] = ROOTCONTEXT_MNT; 968 } 969 if (defcontext) { 970 opts->mnt_opts[num_mnt_opts] = defcontext; 971 opts->mnt_opts_flags[num_mnt_opts++] = DEFCONTEXT_MNT; 972 } 973 974 opts->num_mnt_opts = num_mnt_opts; 975 return 0; 976 977 out_err: 978 kfree(context); 979 kfree(defcontext); 980 kfree(fscontext); 981 kfree(rootcontext); 982 return rc; 983 } 984 /* 985 * string mount options parsing and call set the sbsec 986 */ 987 static int superblock_doinit(struct super_block *sb, void *data) 988 { 989 int rc = 0; 990 char *options = data; 991 struct security_mnt_opts opts; 992 993 security_init_mnt_opts(&opts); 994 995 if (!data) 996 goto out; 997 998 BUG_ON(sb->s_type->fs_flags & FS_BINARY_MOUNTDATA); 999 1000 rc = selinux_parse_opts_str(options, &opts); 1001 if (rc) 1002 goto out_err; 1003 1004 out: 1005 rc = selinux_set_mnt_opts(sb, &opts); 1006 1007 out_err: 1008 security_free_mnt_opts(&opts); 1009 return rc; 1010 } 1011 1012 static void selinux_write_opts(struct seq_file *m, 1013 struct security_mnt_opts *opts) 1014 { 1015 int i; 1016 char *prefix; 1017 1018 for (i = 0; i < opts->num_mnt_opts; i++) { 1019 char *has_comma; 1020 1021 if (opts->mnt_opts[i]) 1022 has_comma = strchr(opts->mnt_opts[i], ','); 1023 else 1024 has_comma = NULL; 1025 1026 switch (opts->mnt_opts_flags[i]) { 1027 case CONTEXT_MNT: 1028 prefix = CONTEXT_STR; 1029 break; 1030 case FSCONTEXT_MNT: 1031 prefix = FSCONTEXT_STR; 1032 break; 1033 case ROOTCONTEXT_MNT: 1034 prefix = ROOTCONTEXT_STR; 1035 break; 1036 case DEFCONTEXT_MNT: 1037 prefix = DEFCONTEXT_STR; 1038 break; 1039 case SE_SBLABELSUPP: 1040 seq_putc(m, ','); 1041 seq_puts(m, LABELSUPP_STR); 1042 continue; 1043 default: 1044 BUG(); 1045 }; 1046 /* we need a comma before each option */ 1047 seq_putc(m, ','); 1048 seq_puts(m, prefix); 1049 if (has_comma) 1050 seq_putc(m, '\"'); 1051 seq_puts(m, opts->mnt_opts[i]); 1052 if (has_comma) 1053 seq_putc(m, '\"'); 1054 } 1055 } 1056 1057 static int selinux_sb_show_options(struct seq_file *m, struct super_block *sb) 1058 { 1059 struct security_mnt_opts opts; 1060 int rc; 1061 1062 rc = selinux_get_mnt_opts(sb, &opts); 1063 if (rc) { 1064 /* before policy load we may get EINVAL, don't show anything */ 1065 if (rc == -EINVAL) 1066 rc = 0; 1067 return rc; 1068 } 1069 1070 selinux_write_opts(m, &opts); 1071 1072 security_free_mnt_opts(&opts); 1073 1074 return rc; 1075 } 1076 1077 static inline u16 inode_mode_to_security_class(umode_t mode) 1078 { 1079 switch (mode & S_IFMT) { 1080 case S_IFSOCK: 1081 return SECCLASS_SOCK_FILE; 1082 case S_IFLNK: 1083 return SECCLASS_LNK_FILE; 1084 case S_IFREG: 1085 return SECCLASS_FILE; 1086 case S_IFBLK: 1087 return SECCLASS_BLK_FILE; 1088 case S_IFDIR: 1089 return SECCLASS_DIR; 1090 case S_IFCHR: 1091 return SECCLASS_CHR_FILE; 1092 case S_IFIFO: 1093 return SECCLASS_FIFO_FILE; 1094 1095 } 1096 1097 return SECCLASS_FILE; 1098 } 1099 1100 static inline int default_protocol_stream(int protocol) 1101 { 1102 return (protocol == IPPROTO_IP || protocol == IPPROTO_TCP); 1103 } 1104 1105 static inline int default_protocol_dgram(int protocol) 1106 { 1107 return (protocol == IPPROTO_IP || protocol == IPPROTO_UDP); 1108 } 1109 1110 static inline u16 socket_type_to_security_class(int family, int type, int protocol) 1111 { 1112 switch (family) { 1113 case PF_UNIX: 1114 switch (type) { 1115 case SOCK_STREAM: 1116 case SOCK_SEQPACKET: 1117 return SECCLASS_UNIX_STREAM_SOCKET; 1118 case SOCK_DGRAM: 1119 return SECCLASS_UNIX_DGRAM_SOCKET; 1120 } 1121 break; 1122 case PF_INET: 1123 case PF_INET6: 1124 switch (type) { 1125 case SOCK_STREAM: 1126 if (default_protocol_stream(protocol)) 1127 return SECCLASS_TCP_SOCKET; 1128 else 1129 return SECCLASS_RAWIP_SOCKET; 1130 case SOCK_DGRAM: 1131 if (default_protocol_dgram(protocol)) 1132 return SECCLASS_UDP_SOCKET; 1133 else 1134 return SECCLASS_RAWIP_SOCKET; 1135 case SOCK_DCCP: 1136 return SECCLASS_DCCP_SOCKET; 1137 default: 1138 return SECCLASS_RAWIP_SOCKET; 1139 } 1140 break; 1141 case PF_NETLINK: 1142 switch (protocol) { 1143 case NETLINK_ROUTE: 1144 return SECCLASS_NETLINK_ROUTE_SOCKET; 1145 case NETLINK_FIREWALL: 1146 return SECCLASS_NETLINK_FIREWALL_SOCKET; 1147 case NETLINK_INET_DIAG: 1148 return SECCLASS_NETLINK_TCPDIAG_SOCKET; 1149 case NETLINK_NFLOG: 1150 return SECCLASS_NETLINK_NFLOG_SOCKET; 1151 case NETLINK_XFRM: 1152 return SECCLASS_NETLINK_XFRM_SOCKET; 1153 case NETLINK_SELINUX: 1154 return SECCLASS_NETLINK_SELINUX_SOCKET; 1155 case NETLINK_AUDIT: 1156 return SECCLASS_NETLINK_AUDIT_SOCKET; 1157 case NETLINK_IP6_FW: 1158 return SECCLASS_NETLINK_IP6FW_SOCKET; 1159 case NETLINK_DNRTMSG: 1160 return SECCLASS_NETLINK_DNRT_SOCKET; 1161 case NETLINK_KOBJECT_UEVENT: 1162 return SECCLASS_NETLINK_KOBJECT_UEVENT_SOCKET; 1163 default: 1164 return SECCLASS_NETLINK_SOCKET; 1165 } 1166 case PF_PACKET: 1167 return SECCLASS_PACKET_SOCKET; 1168 case PF_KEY: 1169 return SECCLASS_KEY_SOCKET; 1170 case PF_APPLETALK: 1171 return SECCLASS_APPLETALK_SOCKET; 1172 } 1173 1174 return SECCLASS_SOCKET; 1175 } 1176 1177 #ifdef CONFIG_PROC_FS 1178 static int selinux_proc_get_sid(struct proc_dir_entry *de, 1179 u16 tclass, 1180 u32 *sid) 1181 { 1182 int buflen, rc; 1183 char *buffer, *path, *end; 1184 1185 buffer = (char *)__get_free_page(GFP_KERNEL); 1186 if (!buffer) 1187 return -ENOMEM; 1188 1189 buflen = PAGE_SIZE; 1190 end = buffer+buflen; 1191 *--end = '\0'; 1192 buflen--; 1193 path = end-1; 1194 *path = '/'; 1195 while (de && de != de->parent) { 1196 buflen -= de->namelen + 1; 1197 if (buflen < 0) 1198 break; 1199 end -= de->namelen; 1200 memcpy(end, de->name, de->namelen); 1201 *--end = '/'; 1202 path = end; 1203 de = de->parent; 1204 } 1205 rc = security_genfs_sid("proc", path, tclass, sid); 1206 free_page((unsigned long)buffer); 1207 return rc; 1208 } 1209 #else 1210 static int selinux_proc_get_sid(struct proc_dir_entry *de, 1211 u16 tclass, 1212 u32 *sid) 1213 { 1214 return -EINVAL; 1215 } 1216 #endif 1217 1218 /* The inode's security attributes must be initialized before first use. */ 1219 static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dentry) 1220 { 1221 struct superblock_security_struct *sbsec = NULL; 1222 struct inode_security_struct *isec = inode->i_security; 1223 u32 sid; 1224 struct dentry *dentry; 1225 #define INITCONTEXTLEN 255 1226 char *context = NULL; 1227 unsigned len = 0; 1228 int rc = 0; 1229 1230 if (isec->initialized) 1231 goto out; 1232 1233 mutex_lock(&isec->lock); 1234 if (isec->initialized) 1235 goto out_unlock; 1236 1237 sbsec = inode->i_sb->s_security; 1238 if (!(sbsec->flags & SE_SBINITIALIZED)) { 1239 /* Defer initialization until selinux_complete_init, 1240 after the initial policy is loaded and the security 1241 server is ready to handle calls. */ 1242 spin_lock(&sbsec->isec_lock); 1243 if (list_empty(&isec->list)) 1244 list_add(&isec->list, &sbsec->isec_head); 1245 spin_unlock(&sbsec->isec_lock); 1246 goto out_unlock; 1247 } 1248 1249 switch (sbsec->behavior) { 1250 case SECURITY_FS_USE_XATTR: 1251 if (!inode->i_op->getxattr) { 1252 isec->sid = sbsec->def_sid; 1253 break; 1254 } 1255 1256 /* Need a dentry, since the xattr API requires one. 1257 Life would be simpler if we could just pass the inode. */ 1258 if (opt_dentry) { 1259 /* Called from d_instantiate or d_splice_alias. */ 1260 dentry = dget(opt_dentry); 1261 } else { 1262 /* Called from selinux_complete_init, try to find a dentry. */ 1263 dentry = d_find_alias(inode); 1264 } 1265 if (!dentry) { 1266 /* 1267 * this is can be hit on boot when a file is accessed 1268 * before the policy is loaded. When we load policy we 1269 * may find inodes that have no dentry on the 1270 * sbsec->isec_head list. No reason to complain as these 1271 * will get fixed up the next time we go through 1272 * inode_doinit with a dentry, before these inodes could 1273 * be used again by userspace. 1274 */ 1275 goto out_unlock; 1276 } 1277 1278 len = INITCONTEXTLEN; 1279 context = kmalloc(len+1, GFP_NOFS); 1280 if (!context) { 1281 rc = -ENOMEM; 1282 dput(dentry); 1283 goto out_unlock; 1284 } 1285 context[len] = '\0'; 1286 rc = inode->i_op->getxattr(dentry, XATTR_NAME_SELINUX, 1287 context, len); 1288 if (rc == -ERANGE) { 1289 /* Need a larger buffer. Query for the right size. */ 1290 rc = inode->i_op->getxattr(dentry, XATTR_NAME_SELINUX, 1291 NULL, 0); 1292 if (rc < 0) { 1293 dput(dentry); 1294 goto out_unlock; 1295 } 1296 kfree(context); 1297 len = rc; 1298 context = kmalloc(len+1, GFP_NOFS); 1299 if (!context) { 1300 rc = -ENOMEM; 1301 dput(dentry); 1302 goto out_unlock; 1303 } 1304 context[len] = '\0'; 1305 rc = inode->i_op->getxattr(dentry, 1306 XATTR_NAME_SELINUX, 1307 context, len); 1308 } 1309 dput(dentry); 1310 if (rc < 0) { 1311 if (rc != -ENODATA) { 1312 printk(KERN_WARNING "SELinux: %s: getxattr returned " 1313 "%d for dev=%s ino=%ld\n", __func__, 1314 -rc, inode->i_sb->s_id, inode->i_ino); 1315 kfree(context); 1316 goto out_unlock; 1317 } 1318 /* Map ENODATA to the default file SID */ 1319 sid = sbsec->def_sid; 1320 rc = 0; 1321 } else { 1322 rc = security_context_to_sid_default(context, rc, &sid, 1323 sbsec->def_sid, 1324 GFP_NOFS); 1325 if (rc) { 1326 char *dev = inode->i_sb->s_id; 1327 unsigned long ino = inode->i_ino; 1328 1329 if (rc == -EINVAL) { 1330 if (printk_ratelimit()) 1331 printk(KERN_NOTICE "SELinux: inode=%lu on dev=%s was found to have an invalid " 1332 "context=%s. This indicates you may need to relabel the inode or the " 1333 "filesystem in question.\n", ino, dev, context); 1334 } else { 1335 printk(KERN_WARNING "SELinux: %s: context_to_sid(%s) " 1336 "returned %d for dev=%s ino=%ld\n", 1337 __func__, context, -rc, dev, ino); 1338 } 1339 kfree(context); 1340 /* Leave with the unlabeled SID */ 1341 rc = 0; 1342 break; 1343 } 1344 } 1345 kfree(context); 1346 isec->sid = sid; 1347 break; 1348 case SECURITY_FS_USE_TASK: 1349 isec->sid = isec->task_sid; 1350 break; 1351 case SECURITY_FS_USE_TRANS: 1352 /* Default to the fs SID. */ 1353 isec->sid = sbsec->sid; 1354 1355 /* Try to obtain a transition SID. */ 1356 isec->sclass = inode_mode_to_security_class(inode->i_mode); 1357 rc = security_transition_sid(isec->task_sid, 1358 sbsec->sid, 1359 isec->sclass, 1360 &sid); 1361 if (rc) 1362 goto out_unlock; 1363 isec->sid = sid; 1364 break; 1365 case SECURITY_FS_USE_MNTPOINT: 1366 isec->sid = sbsec->mntpoint_sid; 1367 break; 1368 default: 1369 /* Default to the fs superblock SID. */ 1370 isec->sid = sbsec->sid; 1371 1372 if ((sbsec->flags & SE_SBPROC) && !S_ISLNK(inode->i_mode)) { 1373 struct proc_inode *proci = PROC_I(inode); 1374 if (proci->pde) { 1375 isec->sclass = inode_mode_to_security_class(inode->i_mode); 1376 rc = selinux_proc_get_sid(proci->pde, 1377 isec->sclass, 1378 &sid); 1379 if (rc) 1380 goto out_unlock; 1381 isec->sid = sid; 1382 } 1383 } 1384 break; 1385 } 1386 1387 isec->initialized = 1; 1388 1389 out_unlock: 1390 mutex_unlock(&isec->lock); 1391 out: 1392 if (isec->sclass == SECCLASS_FILE) 1393 isec->sclass = inode_mode_to_security_class(inode->i_mode); 1394 return rc; 1395 } 1396 1397 /* Convert a Linux signal to an access vector. */ 1398 static inline u32 signal_to_av(int sig) 1399 { 1400 u32 perm = 0; 1401 1402 switch (sig) { 1403 case SIGCHLD: 1404 /* Commonly granted from child to parent. */ 1405 perm = PROCESS__SIGCHLD; 1406 break; 1407 case SIGKILL: 1408 /* Cannot be caught or ignored */ 1409 perm = PROCESS__SIGKILL; 1410 break; 1411 case SIGSTOP: 1412 /* Cannot be caught or ignored */ 1413 perm = PROCESS__SIGSTOP; 1414 break; 1415 default: 1416 /* All other signals. */ 1417 perm = PROCESS__SIGNAL; 1418 break; 1419 } 1420 1421 return perm; 1422 } 1423 1424 /* 1425 * Check permission between a pair of credentials 1426 * fork check, ptrace check, etc. 1427 */ 1428 static int cred_has_perm(const struct cred *actor, 1429 const struct cred *target, 1430 u32 perms) 1431 { 1432 u32 asid = cred_sid(actor), tsid = cred_sid(target); 1433 1434 return avc_has_perm(asid, tsid, SECCLASS_PROCESS, perms, NULL); 1435 } 1436 1437 /* 1438 * Check permission between a pair of tasks, e.g. signal checks, 1439 * fork check, ptrace check, etc. 1440 * tsk1 is the actor and tsk2 is the target 1441 * - this uses the default subjective creds of tsk1 1442 */ 1443 static int task_has_perm(const struct task_struct *tsk1, 1444 const struct task_struct *tsk2, 1445 u32 perms) 1446 { 1447 const struct task_security_struct *__tsec1, *__tsec2; 1448 u32 sid1, sid2; 1449 1450 rcu_read_lock(); 1451 __tsec1 = __task_cred(tsk1)->security; sid1 = __tsec1->sid; 1452 __tsec2 = __task_cred(tsk2)->security; sid2 = __tsec2->sid; 1453 rcu_read_unlock(); 1454 return avc_has_perm(sid1, sid2, SECCLASS_PROCESS, perms, NULL); 1455 } 1456 1457 /* 1458 * Check permission between current and another task, e.g. signal checks, 1459 * fork check, ptrace check, etc. 1460 * current is the actor and tsk2 is the target 1461 * - this uses current's subjective creds 1462 */ 1463 static int current_has_perm(const struct task_struct *tsk, 1464 u32 perms) 1465 { 1466 u32 sid, tsid; 1467 1468 sid = current_sid(); 1469 tsid = task_sid(tsk); 1470 return avc_has_perm(sid, tsid, SECCLASS_PROCESS, perms, NULL); 1471 } 1472 1473 #if CAP_LAST_CAP > 63 1474 #error Fix SELinux to handle capabilities > 63. 1475 #endif 1476 1477 /* Check whether a task is allowed to use a capability. */ 1478 static int task_has_capability(struct task_struct *tsk, 1479 const struct cred *cred, 1480 int cap, int audit) 1481 { 1482 struct avc_audit_data ad; 1483 struct av_decision avd; 1484 u16 sclass; 1485 u32 sid = cred_sid(cred); 1486 u32 av = CAP_TO_MASK(cap); 1487 int rc; 1488 1489 AVC_AUDIT_DATA_INIT(&ad, CAP); 1490 ad.tsk = tsk; 1491 ad.u.cap = cap; 1492 1493 switch (CAP_TO_INDEX(cap)) { 1494 case 0: 1495 sclass = SECCLASS_CAPABILITY; 1496 break; 1497 case 1: 1498 sclass = SECCLASS_CAPABILITY2; 1499 break; 1500 default: 1501 printk(KERN_ERR 1502 "SELinux: out of range capability %d\n", cap); 1503 BUG(); 1504 } 1505 1506 rc = avc_has_perm_noaudit(sid, sid, sclass, av, 0, &avd); 1507 if (audit == SECURITY_CAP_AUDIT) 1508 avc_audit(sid, sid, sclass, av, &avd, rc, &ad); 1509 return rc; 1510 } 1511 1512 /* Check whether a task is allowed to use a system operation. */ 1513 static int task_has_system(struct task_struct *tsk, 1514 u32 perms) 1515 { 1516 u32 sid = task_sid(tsk); 1517 1518 return avc_has_perm(sid, SECINITSID_KERNEL, 1519 SECCLASS_SYSTEM, perms, NULL); 1520 } 1521 1522 /* Check whether a task has a particular permission to an inode. 1523 The 'adp' parameter is optional and allows other audit 1524 data to be passed (e.g. the dentry). */ 1525 static int inode_has_perm(const struct cred *cred, 1526 struct inode *inode, 1527 u32 perms, 1528 struct avc_audit_data *adp) 1529 { 1530 struct inode_security_struct *isec; 1531 struct avc_audit_data ad; 1532 u32 sid; 1533 1534 if (unlikely(IS_PRIVATE(inode))) 1535 return 0; 1536 1537 sid = cred_sid(cred); 1538 isec = inode->i_security; 1539 1540 if (!adp) { 1541 adp = &ad; 1542 AVC_AUDIT_DATA_INIT(&ad, FS); 1543 ad.u.fs.inode = inode; 1544 } 1545 1546 return avc_has_perm(sid, isec->sid, isec->sclass, perms, adp); 1547 } 1548 1549 /* Same as inode_has_perm, but pass explicit audit data containing 1550 the dentry to help the auditing code to more easily generate the 1551 pathname if needed. */ 1552 static inline int dentry_has_perm(const struct cred *cred, 1553 struct vfsmount *mnt, 1554 struct dentry *dentry, 1555 u32 av) 1556 { 1557 struct inode *inode = dentry->d_inode; 1558 struct avc_audit_data ad; 1559 1560 AVC_AUDIT_DATA_INIT(&ad, FS); 1561 ad.u.fs.path.mnt = mnt; 1562 ad.u.fs.path.dentry = dentry; 1563 return inode_has_perm(cred, inode, av, &ad); 1564 } 1565 1566 /* Check whether a task can use an open file descriptor to 1567 access an inode in a given way. Check access to the 1568 descriptor itself, and then use dentry_has_perm to 1569 check a particular permission to the file. 1570 Access to the descriptor is implicitly granted if it 1571 has the same SID as the process. If av is zero, then 1572 access to the file is not checked, e.g. for cases 1573 where only the descriptor is affected like seek. */ 1574 static int file_has_perm(const struct cred *cred, 1575 struct file *file, 1576 u32 av) 1577 { 1578 struct file_security_struct *fsec = file->f_security; 1579 struct inode *inode = file->f_path.dentry->d_inode; 1580 struct avc_audit_data ad; 1581 u32 sid = cred_sid(cred); 1582 int rc; 1583 1584 AVC_AUDIT_DATA_INIT(&ad, FS); 1585 ad.u.fs.path = file->f_path; 1586 1587 if (sid != fsec->sid) { 1588 rc = avc_has_perm(sid, fsec->sid, 1589 SECCLASS_FD, 1590 FD__USE, 1591 &ad); 1592 if (rc) 1593 goto out; 1594 } 1595 1596 /* av is zero if only checking access to the descriptor. */ 1597 rc = 0; 1598 if (av) 1599 rc = inode_has_perm(cred, inode, av, &ad); 1600 1601 out: 1602 return rc; 1603 } 1604 1605 /* Check whether a task can create a file. */ 1606 static int may_create(struct inode *dir, 1607 struct dentry *dentry, 1608 u16 tclass) 1609 { 1610 const struct cred *cred = current_cred(); 1611 const struct task_security_struct *tsec = cred->security; 1612 struct inode_security_struct *dsec; 1613 struct superblock_security_struct *sbsec; 1614 u32 sid, newsid; 1615 struct avc_audit_data ad; 1616 int rc; 1617 1618 dsec = dir->i_security; 1619 sbsec = dir->i_sb->s_security; 1620 1621 sid = tsec->sid; 1622 newsid = tsec->create_sid; 1623 1624 AVC_AUDIT_DATA_INIT(&ad, FS); 1625 ad.u.fs.path.dentry = dentry; 1626 1627 rc = avc_has_perm(sid, dsec->sid, SECCLASS_DIR, 1628 DIR__ADD_NAME | DIR__SEARCH, 1629 &ad); 1630 if (rc) 1631 return rc; 1632 1633 if (!newsid || !(sbsec->flags & SE_SBLABELSUPP)) { 1634 rc = security_transition_sid(sid, dsec->sid, tclass, &newsid); 1635 if (rc) 1636 return rc; 1637 } 1638 1639 rc = avc_has_perm(sid, newsid, tclass, FILE__CREATE, &ad); 1640 if (rc) 1641 return rc; 1642 1643 return avc_has_perm(newsid, sbsec->sid, 1644 SECCLASS_FILESYSTEM, 1645 FILESYSTEM__ASSOCIATE, &ad); 1646 } 1647 1648 /* Check whether a task can create a key. */ 1649 static int may_create_key(u32 ksid, 1650 struct task_struct *ctx) 1651 { 1652 u32 sid = task_sid(ctx); 1653 1654 return avc_has_perm(sid, ksid, SECCLASS_KEY, KEY__CREATE, NULL); 1655 } 1656 1657 #define MAY_LINK 0 1658 #define MAY_UNLINK 1 1659 #define MAY_RMDIR 2 1660 1661 /* Check whether a task can link, unlink, or rmdir a file/directory. */ 1662 static int may_link(struct inode *dir, 1663 struct dentry *dentry, 1664 int kind) 1665 1666 { 1667 struct inode_security_struct *dsec, *isec; 1668 struct avc_audit_data ad; 1669 u32 sid = current_sid(); 1670 u32 av; 1671 int rc; 1672 1673 dsec = dir->i_security; 1674 isec = dentry->d_inode->i_security; 1675 1676 AVC_AUDIT_DATA_INIT(&ad, FS); 1677 ad.u.fs.path.dentry = dentry; 1678 1679 av = DIR__SEARCH; 1680 av |= (kind ? DIR__REMOVE_NAME : DIR__ADD_NAME); 1681 rc = avc_has_perm(sid, dsec->sid, SECCLASS_DIR, av, &ad); 1682 if (rc) 1683 return rc; 1684 1685 switch (kind) { 1686 case MAY_LINK: 1687 av = FILE__LINK; 1688 break; 1689 case MAY_UNLINK: 1690 av = FILE__UNLINK; 1691 break; 1692 case MAY_RMDIR: 1693 av = DIR__RMDIR; 1694 break; 1695 default: 1696 printk(KERN_WARNING "SELinux: %s: unrecognized kind %d\n", 1697 __func__, kind); 1698 return 0; 1699 } 1700 1701 rc = avc_has_perm(sid, isec->sid, isec->sclass, av, &ad); 1702 return rc; 1703 } 1704 1705 static inline int may_rename(struct inode *old_dir, 1706 struct dentry *old_dentry, 1707 struct inode *new_dir, 1708 struct dentry *new_dentry) 1709 { 1710 struct inode_security_struct *old_dsec, *new_dsec, *old_isec, *new_isec; 1711 struct avc_audit_data ad; 1712 u32 sid = current_sid(); 1713 u32 av; 1714 int old_is_dir, new_is_dir; 1715 int rc; 1716 1717 old_dsec = old_dir->i_security; 1718 old_isec = old_dentry->d_inode->i_security; 1719 old_is_dir = S_ISDIR(old_dentry->d_inode->i_mode); 1720 new_dsec = new_dir->i_security; 1721 1722 AVC_AUDIT_DATA_INIT(&ad, FS); 1723 1724 ad.u.fs.path.dentry = old_dentry; 1725 rc = avc_has_perm(sid, old_dsec->sid, SECCLASS_DIR, 1726 DIR__REMOVE_NAME | DIR__SEARCH, &ad); 1727 if (rc) 1728 return rc; 1729 rc = avc_has_perm(sid, old_isec->sid, 1730 old_isec->sclass, FILE__RENAME, &ad); 1731 if (rc) 1732 return rc; 1733 if (old_is_dir && new_dir != old_dir) { 1734 rc = avc_has_perm(sid, old_isec->sid, 1735 old_isec->sclass, DIR__REPARENT, &ad); 1736 if (rc) 1737 return rc; 1738 } 1739 1740 ad.u.fs.path.dentry = new_dentry; 1741 av = DIR__ADD_NAME | DIR__SEARCH; 1742 if (new_dentry->d_inode) 1743 av |= DIR__REMOVE_NAME; 1744 rc = avc_has_perm(sid, new_dsec->sid, SECCLASS_DIR, av, &ad); 1745 if (rc) 1746 return rc; 1747 if (new_dentry->d_inode) { 1748 new_isec = new_dentry->d_inode->i_security; 1749 new_is_dir = S_ISDIR(new_dentry->d_inode->i_mode); 1750 rc = avc_has_perm(sid, new_isec->sid, 1751 new_isec->sclass, 1752 (new_is_dir ? DIR__RMDIR : FILE__UNLINK), &ad); 1753 if (rc) 1754 return rc; 1755 } 1756 1757 return 0; 1758 } 1759 1760 /* Check whether a task can perform a filesystem operation. */ 1761 static int superblock_has_perm(const struct cred *cred, 1762 struct super_block *sb, 1763 u32 perms, 1764 struct avc_audit_data *ad) 1765 { 1766 struct superblock_security_struct *sbsec; 1767 u32 sid = cred_sid(cred); 1768 1769 sbsec = sb->s_security; 1770 return avc_has_perm(sid, sbsec->sid, SECCLASS_FILESYSTEM, perms, ad); 1771 } 1772 1773 /* Convert a Linux mode and permission mask to an access vector. */ 1774 static inline u32 file_mask_to_av(int mode, int mask) 1775 { 1776 u32 av = 0; 1777 1778 if ((mode & S_IFMT) != S_IFDIR) { 1779 if (mask & MAY_EXEC) 1780 av |= FILE__EXECUTE; 1781 if (mask & MAY_READ) 1782 av |= FILE__READ; 1783 1784 if (mask & MAY_APPEND) 1785 av |= FILE__APPEND; 1786 else if (mask & MAY_WRITE) 1787 av |= FILE__WRITE; 1788 1789 } else { 1790 if (mask & MAY_EXEC) 1791 av |= DIR__SEARCH; 1792 if (mask & MAY_WRITE) 1793 av |= DIR__WRITE; 1794 if (mask & MAY_READ) 1795 av |= DIR__READ; 1796 } 1797 1798 return av; 1799 } 1800 1801 /* Convert a Linux file to an access vector. */ 1802 static inline u32 file_to_av(struct file *file) 1803 { 1804 u32 av = 0; 1805 1806 if (file->f_mode & FMODE_READ) 1807 av |= FILE__READ; 1808 if (file->f_mode & FMODE_WRITE) { 1809 if (file->f_flags & O_APPEND) 1810 av |= FILE__APPEND; 1811 else 1812 av |= FILE__WRITE; 1813 } 1814 if (!av) { 1815 /* 1816 * Special file opened with flags 3 for ioctl-only use. 1817 */ 1818 av = FILE__IOCTL; 1819 } 1820 1821 return av; 1822 } 1823 1824 /* 1825 * Convert a file to an access vector and include the correct open 1826 * open permission. 1827 */ 1828 static inline u32 open_file_to_av(struct file *file) 1829 { 1830 u32 av = file_to_av(file); 1831 1832 if (selinux_policycap_openperm) { 1833 mode_t mode = file->f_path.dentry->d_inode->i_mode; 1834 /* 1835 * lnk files and socks do not really have an 'open' 1836 */ 1837 if (S_ISREG(mode)) 1838 av |= FILE__OPEN; 1839 else if (S_ISCHR(mode)) 1840 av |= CHR_FILE__OPEN; 1841 else if (S_ISBLK(mode)) 1842 av |= BLK_FILE__OPEN; 1843 else if (S_ISFIFO(mode)) 1844 av |= FIFO_FILE__OPEN; 1845 else if (S_ISDIR(mode)) 1846 av |= DIR__OPEN; 1847 else if (S_ISSOCK(mode)) 1848 av |= SOCK_FILE__OPEN; 1849 else 1850 printk(KERN_ERR "SELinux: WARNING: inside %s with " 1851 "unknown mode:%o\n", __func__, mode); 1852 } 1853 return av; 1854 } 1855 1856 /* Hook functions begin here. */ 1857 1858 static int selinux_ptrace_may_access(struct task_struct *child, 1859 unsigned int mode) 1860 { 1861 int rc; 1862 1863 rc = cap_ptrace_may_access(child, mode); 1864 if (rc) 1865 return rc; 1866 1867 if (mode == PTRACE_MODE_READ) { 1868 u32 sid = current_sid(); 1869 u32 csid = task_sid(child); 1870 return avc_has_perm(sid, csid, SECCLASS_FILE, FILE__READ, NULL); 1871 } 1872 1873 return current_has_perm(child, PROCESS__PTRACE); 1874 } 1875 1876 static int selinux_ptrace_traceme(struct task_struct *parent) 1877 { 1878 int rc; 1879 1880 rc = cap_ptrace_traceme(parent); 1881 if (rc) 1882 return rc; 1883 1884 return task_has_perm(parent, current, PROCESS__PTRACE); 1885 } 1886 1887 static int selinux_capget(struct task_struct *target, kernel_cap_t *effective, 1888 kernel_cap_t *inheritable, kernel_cap_t *permitted) 1889 { 1890 int error; 1891 1892 error = current_has_perm(target, PROCESS__GETCAP); 1893 if (error) 1894 return error; 1895 1896 return cap_capget(target, effective, inheritable, permitted); 1897 } 1898 1899 static int selinux_capset(struct cred *new, const struct cred *old, 1900 const kernel_cap_t *effective, 1901 const kernel_cap_t *inheritable, 1902 const kernel_cap_t *permitted) 1903 { 1904 int error; 1905 1906 error = cap_capset(new, old, 1907 effective, inheritable, permitted); 1908 if (error) 1909 return error; 1910 1911 return cred_has_perm(old, new, PROCESS__SETCAP); 1912 } 1913 1914 /* 1915 * (This comment used to live with the selinux_task_setuid hook, 1916 * which was removed). 1917 * 1918 * Since setuid only affects the current process, and since the SELinux 1919 * controls are not based on the Linux identity attributes, SELinux does not 1920 * need to control this operation. However, SELinux does control the use of 1921 * the CAP_SETUID and CAP_SETGID capabilities using the capable hook. 1922 */ 1923 1924 static int selinux_capable(struct task_struct *tsk, const struct cred *cred, 1925 int cap, int audit) 1926 { 1927 int rc; 1928 1929 rc = cap_capable(tsk, cred, cap, audit); 1930 if (rc) 1931 return rc; 1932 1933 return task_has_capability(tsk, cred, cap, audit); 1934 } 1935 1936 static int selinux_sysctl_get_sid(ctl_table *table, u16 tclass, u32 *sid) 1937 { 1938 int buflen, rc; 1939 char *buffer, *path, *end; 1940 1941 rc = -ENOMEM; 1942 buffer = (char *)__get_free_page(GFP_KERNEL); 1943 if (!buffer) 1944 goto out; 1945 1946 buflen = PAGE_SIZE; 1947 end = buffer+buflen; 1948 *--end = '\0'; 1949 buflen--; 1950 path = end-1; 1951 *path = '/'; 1952 while (table) { 1953 const char *name = table->procname; 1954 size_t namelen = strlen(name); 1955 buflen -= namelen + 1; 1956 if (buflen < 0) 1957 goto out_free; 1958 end -= namelen; 1959 memcpy(end, name, namelen); 1960 *--end = '/'; 1961 path = end; 1962 table = table->parent; 1963 } 1964 buflen -= 4; 1965 if (buflen < 0) 1966 goto out_free; 1967 end -= 4; 1968 memcpy(end, "/sys", 4); 1969 path = end; 1970 rc = security_genfs_sid("proc", path, tclass, sid); 1971 out_free: 1972 free_page((unsigned long)buffer); 1973 out: 1974 return rc; 1975 } 1976 1977 static int selinux_sysctl(ctl_table *table, int op) 1978 { 1979 int error = 0; 1980 u32 av; 1981 u32 tsid, sid; 1982 int rc; 1983 1984 rc = secondary_ops->sysctl(table, op); 1985 if (rc) 1986 return rc; 1987 1988 sid = current_sid(); 1989 1990 rc = selinux_sysctl_get_sid(table, (op == 0001) ? 1991 SECCLASS_DIR : SECCLASS_FILE, &tsid); 1992 if (rc) { 1993 /* Default to the well-defined sysctl SID. */ 1994 tsid = SECINITSID_SYSCTL; 1995 } 1996 1997 /* The op values are "defined" in sysctl.c, thereby creating 1998 * a bad coupling between this module and sysctl.c */ 1999 if (op == 001) { 2000 error = avc_has_perm(sid, tsid, 2001 SECCLASS_DIR, DIR__SEARCH, NULL); 2002 } else { 2003 av = 0; 2004 if (op & 004) 2005 av |= FILE__READ; 2006 if (op & 002) 2007 av |= FILE__WRITE; 2008 if (av) 2009 error = avc_has_perm(sid, tsid, 2010 SECCLASS_FILE, av, NULL); 2011 } 2012 2013 return error; 2014 } 2015 2016 static int selinux_quotactl(int cmds, int type, int id, struct super_block *sb) 2017 { 2018 const struct cred *cred = current_cred(); 2019 int rc = 0; 2020 2021 if (!sb) 2022 return 0; 2023 2024 switch (cmds) { 2025 case Q_SYNC: 2026 case Q_QUOTAON: 2027 case Q_QUOTAOFF: 2028 case Q_SETINFO: 2029 case Q_SETQUOTA: 2030 rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAMOD, NULL); 2031 break; 2032 case Q_GETFMT: 2033 case Q_GETINFO: 2034 case Q_GETQUOTA: 2035 rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAGET, NULL); 2036 break; 2037 default: 2038 rc = 0; /* let the kernel handle invalid cmds */ 2039 break; 2040 } 2041 return rc; 2042 } 2043 2044 static int selinux_quota_on(struct dentry *dentry) 2045 { 2046 const struct cred *cred = current_cred(); 2047 2048 return dentry_has_perm(cred, NULL, dentry, FILE__QUOTAON); 2049 } 2050 2051 static int selinux_syslog(int type) 2052 { 2053 int rc; 2054 2055 rc = cap_syslog(type); 2056 if (rc) 2057 return rc; 2058 2059 switch (type) { 2060 case 3: /* Read last kernel messages */ 2061 case 10: /* Return size of the log buffer */ 2062 rc = task_has_system(current, SYSTEM__SYSLOG_READ); 2063 break; 2064 case 6: /* Disable logging to console */ 2065 case 7: /* Enable logging to console */ 2066 case 8: /* Set level of messages printed to console */ 2067 rc = task_has_system(current, SYSTEM__SYSLOG_CONSOLE); 2068 break; 2069 case 0: /* Close log */ 2070 case 1: /* Open log */ 2071 case 2: /* Read from log */ 2072 case 4: /* Read/clear last kernel messages */ 2073 case 5: /* Clear ring buffer */ 2074 default: 2075 rc = task_has_system(current, SYSTEM__SYSLOG_MOD); 2076 break; 2077 } 2078 return rc; 2079 } 2080 2081 /* 2082 * Check that a process has enough memory to allocate a new virtual 2083 * mapping. 0 means there is enough memory for the allocation to 2084 * succeed and -ENOMEM implies there is not. 2085 * 2086 * Do not audit the selinux permission check, as this is applied to all 2087 * processes that allocate mappings. 2088 */ 2089 static int selinux_vm_enough_memory(struct mm_struct *mm, long pages) 2090 { 2091 int rc, cap_sys_admin = 0; 2092 2093 rc = selinux_capable(current, current_cred(), CAP_SYS_ADMIN, 2094 SECURITY_CAP_NOAUDIT); 2095 if (rc == 0) 2096 cap_sys_admin = 1; 2097 2098 return __vm_enough_memory(mm, pages, cap_sys_admin); 2099 } 2100 2101 /* binprm security operations */ 2102 2103 static int selinux_bprm_set_creds(struct linux_binprm *bprm) 2104 { 2105 const struct task_security_struct *old_tsec; 2106 struct task_security_struct *new_tsec; 2107 struct inode_security_struct *isec; 2108 struct avc_audit_data ad; 2109 struct inode *inode = bprm->file->f_path.dentry->d_inode; 2110 int rc; 2111 2112 rc = cap_bprm_set_creds(bprm); 2113 if (rc) 2114 return rc; 2115 2116 /* SELinux context only depends on initial program or script and not 2117 * the script interpreter */ 2118 if (bprm->cred_prepared) 2119 return 0; 2120 2121 old_tsec = current_security(); 2122 new_tsec = bprm->cred->security; 2123 isec = inode->i_security; 2124 2125 /* Default to the current task SID. */ 2126 new_tsec->sid = old_tsec->sid; 2127 new_tsec->osid = old_tsec->sid; 2128 2129 /* Reset fs, key, and sock SIDs on execve. */ 2130 new_tsec->create_sid = 0; 2131 new_tsec->keycreate_sid = 0; 2132 new_tsec->sockcreate_sid = 0; 2133 2134 if (old_tsec->exec_sid) { 2135 new_tsec->sid = old_tsec->exec_sid; 2136 /* Reset exec SID on execve. */ 2137 new_tsec->exec_sid = 0; 2138 } else { 2139 /* Check for a default transition on this program. */ 2140 rc = security_transition_sid(old_tsec->sid, isec->sid, 2141 SECCLASS_PROCESS, &new_tsec->sid); 2142 if (rc) 2143 return rc; 2144 } 2145 2146 AVC_AUDIT_DATA_INIT(&ad, FS); 2147 ad.u.fs.path = bprm->file->f_path; 2148 2149 if (bprm->file->f_path.mnt->mnt_flags & MNT_NOSUID) 2150 new_tsec->sid = old_tsec->sid; 2151 2152 if (new_tsec->sid == old_tsec->sid) { 2153 rc = avc_has_perm(old_tsec->sid, isec->sid, 2154 SECCLASS_FILE, FILE__EXECUTE_NO_TRANS, &ad); 2155 if (rc) 2156 return rc; 2157 } else { 2158 /* Check permissions for the transition. */ 2159 rc = avc_has_perm(old_tsec->sid, new_tsec->sid, 2160 SECCLASS_PROCESS, PROCESS__TRANSITION, &ad); 2161 if (rc) 2162 return rc; 2163 2164 rc = avc_has_perm(new_tsec->sid, isec->sid, 2165 SECCLASS_FILE, FILE__ENTRYPOINT, &ad); 2166 if (rc) 2167 return rc; 2168 2169 /* Check for shared state */ 2170 if (bprm->unsafe & LSM_UNSAFE_SHARE) { 2171 rc = avc_has_perm(old_tsec->sid, new_tsec->sid, 2172 SECCLASS_PROCESS, PROCESS__SHARE, 2173 NULL); 2174 if (rc) 2175 return -EPERM; 2176 } 2177 2178 /* Make sure that anyone attempting to ptrace over a task that 2179 * changes its SID has the appropriate permit */ 2180 if (bprm->unsafe & 2181 (LSM_UNSAFE_PTRACE | LSM_UNSAFE_PTRACE_CAP)) { 2182 struct task_struct *tracer; 2183 struct task_security_struct *sec; 2184 u32 ptsid = 0; 2185 2186 rcu_read_lock(); 2187 tracer = tracehook_tracer_task(current); 2188 if (likely(tracer != NULL)) { 2189 sec = __task_cred(tracer)->security; 2190 ptsid = sec->sid; 2191 } 2192 rcu_read_unlock(); 2193 2194 if (ptsid != 0) { 2195 rc = avc_has_perm(ptsid, new_tsec->sid, 2196 SECCLASS_PROCESS, 2197 PROCESS__PTRACE, NULL); 2198 if (rc) 2199 return -EPERM; 2200 } 2201 } 2202 2203 /* Clear any possibly unsafe personality bits on exec: */ 2204 bprm->per_clear |= PER_CLEAR_ON_SETID; 2205 } 2206 2207 return 0; 2208 } 2209 2210 static int selinux_bprm_secureexec(struct linux_binprm *bprm) 2211 { 2212 const struct cred *cred = current_cred(); 2213 const struct task_security_struct *tsec = cred->security; 2214 u32 sid, osid; 2215 int atsecure = 0; 2216 2217 sid = tsec->sid; 2218 osid = tsec->osid; 2219 2220 if (osid != sid) { 2221 /* Enable secure mode for SIDs transitions unless 2222 the noatsecure permission is granted between 2223 the two SIDs, i.e. ahp returns 0. */ 2224 atsecure = avc_has_perm(osid, sid, 2225 SECCLASS_PROCESS, 2226 PROCESS__NOATSECURE, NULL); 2227 } 2228 2229 return (atsecure || cap_bprm_secureexec(bprm)); 2230 } 2231 2232 extern struct vfsmount *selinuxfs_mount; 2233 extern struct dentry *selinux_null; 2234 2235 /* Derived from fs/exec.c:flush_old_files. */ 2236 static inline void flush_unauthorized_files(const struct cred *cred, 2237 struct files_struct *files) 2238 { 2239 struct avc_audit_data ad; 2240 struct file *file, *devnull = NULL; 2241 struct tty_struct *tty; 2242 struct fdtable *fdt; 2243 long j = -1; 2244 int drop_tty = 0; 2245 2246 tty = get_current_tty(); 2247 if (tty) { 2248 file_list_lock(); 2249 if (!list_empty(&tty->tty_files)) { 2250 struct inode *inode; 2251 2252 /* Revalidate access to controlling tty. 2253 Use inode_has_perm on the tty inode directly rather 2254 than using file_has_perm, as this particular open 2255 file may belong to another process and we are only 2256 interested in the inode-based check here. */ 2257 file = list_first_entry(&tty->tty_files, struct file, f_u.fu_list); 2258 inode = file->f_path.dentry->d_inode; 2259 if (inode_has_perm(cred, inode, 2260 FILE__READ | FILE__WRITE, NULL)) { 2261 drop_tty = 1; 2262 } 2263 } 2264 file_list_unlock(); 2265 tty_kref_put(tty); 2266 } 2267 /* Reset controlling tty. */ 2268 if (drop_tty) 2269 no_tty(); 2270 2271 /* Revalidate access to inherited open files. */ 2272 2273 AVC_AUDIT_DATA_INIT(&ad, FS); 2274 2275 spin_lock(&files->file_lock); 2276 for (;;) { 2277 unsigned long set, i; 2278 int fd; 2279 2280 j++; 2281 i = j * __NFDBITS; 2282 fdt = files_fdtable(files); 2283 if (i >= fdt->max_fds) 2284 break; 2285 set = fdt->open_fds->fds_bits[j]; 2286 if (!set) 2287 continue; 2288 spin_unlock(&files->file_lock); 2289 for ( ; set ; i++, set >>= 1) { 2290 if (set & 1) { 2291 file = fget(i); 2292 if (!file) 2293 continue; 2294 if (file_has_perm(cred, 2295 file, 2296 file_to_av(file))) { 2297 sys_close(i); 2298 fd = get_unused_fd(); 2299 if (fd != i) { 2300 if (fd >= 0) 2301 put_unused_fd(fd); 2302 fput(file); 2303 continue; 2304 } 2305 if (devnull) { 2306 get_file(devnull); 2307 } else { 2308 devnull = dentry_open( 2309 dget(selinux_null), 2310 mntget(selinuxfs_mount), 2311 O_RDWR, cred); 2312 if (IS_ERR(devnull)) { 2313 devnull = NULL; 2314 put_unused_fd(fd); 2315 fput(file); 2316 continue; 2317 } 2318 } 2319 fd_install(fd, devnull); 2320 } 2321 fput(file); 2322 } 2323 } 2324 spin_lock(&files->file_lock); 2325 2326 } 2327 spin_unlock(&files->file_lock); 2328 } 2329 2330 /* 2331 * Prepare a process for imminent new credential changes due to exec 2332 */ 2333 static void selinux_bprm_committing_creds(struct linux_binprm *bprm) 2334 { 2335 struct task_security_struct *new_tsec; 2336 struct rlimit *rlim, *initrlim; 2337 int rc, i; 2338 2339 new_tsec = bprm->cred->security; 2340 if (new_tsec->sid == new_tsec->osid) 2341 return; 2342 2343 /* Close files for which the new task SID is not authorized. */ 2344 flush_unauthorized_files(bprm->cred, current->files); 2345 2346 /* Always clear parent death signal on SID transitions. */ 2347 current->pdeath_signal = 0; 2348 2349 /* Check whether the new SID can inherit resource limits from the old 2350 * SID. If not, reset all soft limits to the lower of the current 2351 * task's hard limit and the init task's soft limit. 2352 * 2353 * Note that the setting of hard limits (even to lower them) can be 2354 * controlled by the setrlimit check. The inclusion of the init task's 2355 * soft limit into the computation is to avoid resetting soft limits 2356 * higher than the default soft limit for cases where the default is 2357 * lower than the hard limit, e.g. RLIMIT_CORE or RLIMIT_STACK. 2358 */ 2359 rc = avc_has_perm(new_tsec->osid, new_tsec->sid, SECCLASS_PROCESS, 2360 PROCESS__RLIMITINH, NULL); 2361 if (rc) { 2362 for (i = 0; i < RLIM_NLIMITS; i++) { 2363 rlim = current->signal->rlim + i; 2364 initrlim = init_task.signal->rlim + i; 2365 rlim->rlim_cur = min(rlim->rlim_max, initrlim->rlim_cur); 2366 } 2367 update_rlimit_cpu(rlim->rlim_cur); 2368 } 2369 } 2370 2371 /* 2372 * Clean up the process immediately after the installation of new credentials 2373 * due to exec 2374 */ 2375 static void selinux_bprm_committed_creds(struct linux_binprm *bprm) 2376 { 2377 const struct task_security_struct *tsec = current_security(); 2378 struct itimerval itimer; 2379 struct sighand_struct *psig; 2380 u32 osid, sid; 2381 int rc, i; 2382 unsigned long flags; 2383 2384 osid = tsec->osid; 2385 sid = tsec->sid; 2386 2387 if (sid == osid) 2388 return; 2389 2390 /* Check whether the new SID can inherit signal state from the old SID. 2391 * If not, clear itimers to avoid subsequent signal generation and 2392 * flush and unblock signals. 2393 * 2394 * This must occur _after_ the task SID has been updated so that any 2395 * kill done after the flush will be checked against the new SID. 2396 */ 2397 rc = avc_has_perm(osid, sid, SECCLASS_PROCESS, PROCESS__SIGINH, NULL); 2398 if (rc) { 2399 memset(&itimer, 0, sizeof itimer); 2400 for (i = 0; i < 3; i++) 2401 do_setitimer(i, &itimer, NULL); 2402 flush_signals(current); 2403 spin_lock_irq(¤t->sighand->siglock); 2404 flush_signal_handlers(current, 1); 2405 sigemptyset(¤t->blocked); 2406 recalc_sigpending(); 2407 spin_unlock_irq(¤t->sighand->siglock); 2408 } 2409 2410 /* Wake up the parent if it is waiting so that it can recheck 2411 * wait permission to the new task SID. */ 2412 read_lock_irq(&tasklist_lock); 2413 psig = current->parent->sighand; 2414 spin_lock_irqsave(&psig->siglock, flags); 2415 wake_up_interruptible(¤t->parent->signal->wait_chldexit); 2416 spin_unlock_irqrestore(&psig->siglock, flags); 2417 read_unlock_irq(&tasklist_lock); 2418 } 2419 2420 /* superblock security operations */ 2421 2422 static int selinux_sb_alloc_security(struct super_block *sb) 2423 { 2424 return superblock_alloc_security(sb); 2425 } 2426 2427 static void selinux_sb_free_security(struct super_block *sb) 2428 { 2429 superblock_free_security(sb); 2430 } 2431 2432 static inline int match_prefix(char *prefix, int plen, char *option, int olen) 2433 { 2434 if (plen > olen) 2435 return 0; 2436 2437 return !memcmp(prefix, option, plen); 2438 } 2439 2440 static inline int selinux_option(char *option, int len) 2441 { 2442 return (match_prefix(CONTEXT_STR, sizeof(CONTEXT_STR)-1, option, len) || 2443 match_prefix(FSCONTEXT_STR, sizeof(FSCONTEXT_STR)-1, option, len) || 2444 match_prefix(DEFCONTEXT_STR, sizeof(DEFCONTEXT_STR)-1, option, len) || 2445 match_prefix(ROOTCONTEXT_STR, sizeof(ROOTCONTEXT_STR)-1, option, len) || 2446 match_prefix(LABELSUPP_STR, sizeof(LABELSUPP_STR)-1, option, len)); 2447 } 2448 2449 static inline void take_option(char **to, char *from, int *first, int len) 2450 { 2451 if (!*first) { 2452 **to = ','; 2453 *to += 1; 2454 } else 2455 *first = 0; 2456 memcpy(*to, from, len); 2457 *to += len; 2458 } 2459 2460 static inline void take_selinux_option(char **to, char *from, int *first, 2461 int len) 2462 { 2463 int current_size = 0; 2464 2465 if (!*first) { 2466 **to = '|'; 2467 *to += 1; 2468 } else 2469 *first = 0; 2470 2471 while (current_size < len) { 2472 if (*from != '"') { 2473 **to = *from; 2474 *to += 1; 2475 } 2476 from += 1; 2477 current_size += 1; 2478 } 2479 } 2480 2481 static int selinux_sb_copy_data(char *orig, char *copy) 2482 { 2483 int fnosec, fsec, rc = 0; 2484 char *in_save, *in_curr, *in_end; 2485 char *sec_curr, *nosec_save, *nosec; 2486 int open_quote = 0; 2487 2488 in_curr = orig; 2489 sec_curr = copy; 2490 2491 nosec = (char *)get_zeroed_page(GFP_KERNEL); 2492 if (!nosec) { 2493 rc = -ENOMEM; 2494 goto out; 2495 } 2496 2497 nosec_save = nosec; 2498 fnosec = fsec = 1; 2499 in_save = in_end = orig; 2500 2501 do { 2502 if (*in_end == '"') 2503 open_quote = !open_quote; 2504 if ((*in_end == ',' && open_quote == 0) || 2505 *in_end == '\0') { 2506 int len = in_end - in_curr; 2507 2508 if (selinux_option(in_curr, len)) 2509 take_selinux_option(&sec_curr, in_curr, &fsec, len); 2510 else 2511 take_option(&nosec, in_curr, &fnosec, len); 2512 2513 in_curr = in_end + 1; 2514 } 2515 } while (*in_end++); 2516 2517 strcpy(in_save, nosec_save); 2518 free_page((unsigned long)nosec_save); 2519 out: 2520 return rc; 2521 } 2522 2523 static int selinux_sb_kern_mount(struct super_block *sb, int flags, void *data) 2524 { 2525 const struct cred *cred = current_cred(); 2526 struct avc_audit_data ad; 2527 int rc; 2528 2529 rc = superblock_doinit(sb, data); 2530 if (rc) 2531 return rc; 2532 2533 /* Allow all mounts performed by the kernel */ 2534 if (flags & MS_KERNMOUNT) 2535 return 0; 2536 2537 AVC_AUDIT_DATA_INIT(&ad, FS); 2538 ad.u.fs.path.dentry = sb->s_root; 2539 return superblock_has_perm(cred, sb, FILESYSTEM__MOUNT, &ad); 2540 } 2541 2542 static int selinux_sb_statfs(struct dentry *dentry) 2543 { 2544 const struct cred *cred = current_cred(); 2545 struct avc_audit_data ad; 2546 2547 AVC_AUDIT_DATA_INIT(&ad, FS); 2548 ad.u.fs.path.dentry = dentry->d_sb->s_root; 2549 return superblock_has_perm(cred, dentry->d_sb, FILESYSTEM__GETATTR, &ad); 2550 } 2551 2552 static int selinux_mount(char *dev_name, 2553 struct path *path, 2554 char *type, 2555 unsigned long flags, 2556 void *data) 2557 { 2558 const struct cred *cred = current_cred(); 2559 2560 if (flags & MS_REMOUNT) 2561 return superblock_has_perm(cred, path->mnt->mnt_sb, 2562 FILESYSTEM__REMOUNT, NULL); 2563 else 2564 return dentry_has_perm(cred, path->mnt, path->dentry, 2565 FILE__MOUNTON); 2566 } 2567 2568 static int selinux_umount(struct vfsmount *mnt, int flags) 2569 { 2570 const struct cred *cred = current_cred(); 2571 2572 return superblock_has_perm(cred, mnt->mnt_sb, 2573 FILESYSTEM__UNMOUNT, NULL); 2574 } 2575 2576 /* inode security operations */ 2577 2578 static int selinux_inode_alloc_security(struct inode *inode) 2579 { 2580 return inode_alloc_security(inode); 2581 } 2582 2583 static void selinux_inode_free_security(struct inode *inode) 2584 { 2585 inode_free_security(inode); 2586 } 2587 2588 static int selinux_inode_init_security(struct inode *inode, struct inode *dir, 2589 char **name, void **value, 2590 size_t *len) 2591 { 2592 const struct cred *cred = current_cred(); 2593 const struct task_security_struct *tsec = cred->security; 2594 struct inode_security_struct *dsec; 2595 struct superblock_security_struct *sbsec; 2596 u32 sid, newsid, clen; 2597 int rc; 2598 char *namep = NULL, *context; 2599 2600 dsec = dir->i_security; 2601 sbsec = dir->i_sb->s_security; 2602 2603 sid = tsec->sid; 2604 newsid = tsec->create_sid; 2605 2606 if (!newsid || !(sbsec->flags & SE_SBLABELSUPP)) { 2607 rc = security_transition_sid(sid, dsec->sid, 2608 inode_mode_to_security_class(inode->i_mode), 2609 &newsid); 2610 if (rc) { 2611 printk(KERN_WARNING "%s: " 2612 "security_transition_sid failed, rc=%d (dev=%s " 2613 "ino=%ld)\n", 2614 __func__, 2615 -rc, inode->i_sb->s_id, inode->i_ino); 2616 return rc; 2617 } 2618 } 2619 2620 /* Possibly defer initialization to selinux_complete_init. */ 2621 if (sbsec->flags & SE_SBINITIALIZED) { 2622 struct inode_security_struct *isec = inode->i_security; 2623 isec->sclass = inode_mode_to_security_class(inode->i_mode); 2624 isec->sid = newsid; 2625 isec->initialized = 1; 2626 } 2627 2628 if (!ss_initialized || !(sbsec->flags & SE_SBLABELSUPP)) 2629 return -EOPNOTSUPP; 2630 2631 if (name) { 2632 namep = kstrdup(XATTR_SELINUX_SUFFIX, GFP_NOFS); 2633 if (!namep) 2634 return -ENOMEM; 2635 *name = namep; 2636 } 2637 2638 if (value && len) { 2639 rc = security_sid_to_context_force(newsid, &context, &clen); 2640 if (rc) { 2641 kfree(namep); 2642 return rc; 2643 } 2644 *value = context; 2645 *len = clen; 2646 } 2647 2648 return 0; 2649 } 2650 2651 static int selinux_inode_create(struct inode *dir, struct dentry *dentry, int mask) 2652 { 2653 return may_create(dir, dentry, SECCLASS_FILE); 2654 } 2655 2656 static int selinux_inode_link(struct dentry *old_dentry, struct inode *dir, struct dentry *new_dentry) 2657 { 2658 return may_link(dir, old_dentry, MAY_LINK); 2659 } 2660 2661 static int selinux_inode_unlink(struct inode *dir, struct dentry *dentry) 2662 { 2663 return may_link(dir, dentry, MAY_UNLINK); 2664 } 2665 2666 static int selinux_inode_symlink(struct inode *dir, struct dentry *dentry, const char *name) 2667 { 2668 return may_create(dir, dentry, SECCLASS_LNK_FILE); 2669 } 2670 2671 static int selinux_inode_mkdir(struct inode *dir, struct dentry *dentry, int mask) 2672 { 2673 return may_create(dir, dentry, SECCLASS_DIR); 2674 } 2675 2676 static int selinux_inode_rmdir(struct inode *dir, struct dentry *dentry) 2677 { 2678 return may_link(dir, dentry, MAY_RMDIR); 2679 } 2680 2681 static int selinux_inode_mknod(struct inode *dir, struct dentry *dentry, int mode, dev_t dev) 2682 { 2683 return may_create(dir, dentry, inode_mode_to_security_class(mode)); 2684 } 2685 2686 static int selinux_inode_rename(struct inode *old_inode, struct dentry *old_dentry, 2687 struct inode *new_inode, struct dentry *new_dentry) 2688 { 2689 return may_rename(old_inode, old_dentry, new_inode, new_dentry); 2690 } 2691 2692 static int selinux_inode_readlink(struct dentry *dentry) 2693 { 2694 const struct cred *cred = current_cred(); 2695 2696 return dentry_has_perm(cred, NULL, dentry, FILE__READ); 2697 } 2698 2699 static int selinux_inode_follow_link(struct dentry *dentry, struct nameidata *nameidata) 2700 { 2701 const struct cred *cred = current_cred(); 2702 2703 return dentry_has_perm(cred, NULL, dentry, FILE__READ); 2704 } 2705 2706 static int selinux_inode_permission(struct inode *inode, int mask) 2707 { 2708 const struct cred *cred = current_cred(); 2709 2710 if (!mask) { 2711 /* No permission to check. Existence test. */ 2712 return 0; 2713 } 2714 2715 return inode_has_perm(cred, inode, 2716 file_mask_to_av(inode->i_mode, mask), NULL); 2717 } 2718 2719 static int selinux_inode_setattr(struct dentry *dentry, struct iattr *iattr) 2720 { 2721 const struct cred *cred = current_cred(); 2722 2723 if (iattr->ia_valid & ATTR_FORCE) 2724 return 0; 2725 2726 if (iattr->ia_valid & (ATTR_MODE | ATTR_UID | ATTR_GID | 2727 ATTR_ATIME_SET | ATTR_MTIME_SET)) 2728 return dentry_has_perm(cred, NULL, dentry, FILE__SETATTR); 2729 2730 return dentry_has_perm(cred, NULL, dentry, FILE__WRITE); 2731 } 2732 2733 static int selinux_inode_getattr(struct vfsmount *mnt, struct dentry *dentry) 2734 { 2735 const struct cred *cred = current_cred(); 2736 2737 return dentry_has_perm(cred, mnt, dentry, FILE__GETATTR); 2738 } 2739 2740 static int selinux_inode_setotherxattr(struct dentry *dentry, const char *name) 2741 { 2742 const struct cred *cred = current_cred(); 2743 2744 if (!strncmp(name, XATTR_SECURITY_PREFIX, 2745 sizeof XATTR_SECURITY_PREFIX - 1)) { 2746 if (!strcmp(name, XATTR_NAME_CAPS)) { 2747 if (!capable(CAP_SETFCAP)) 2748 return -EPERM; 2749 } else if (!capable(CAP_SYS_ADMIN)) { 2750 /* A different attribute in the security namespace. 2751 Restrict to administrator. */ 2752 return -EPERM; 2753 } 2754 } 2755 2756 /* Not an attribute we recognize, so just check the 2757 ordinary setattr permission. */ 2758 return dentry_has_perm(cred, NULL, dentry, FILE__SETATTR); 2759 } 2760 2761 static int selinux_inode_setxattr(struct dentry *dentry, const char *name, 2762 const void *value, size_t size, int flags) 2763 { 2764 struct inode *inode = dentry->d_inode; 2765 struct inode_security_struct *isec = inode->i_security; 2766 struct superblock_security_struct *sbsec; 2767 struct avc_audit_data ad; 2768 u32 newsid, sid = current_sid(); 2769 int rc = 0; 2770 2771 if (strcmp(name, XATTR_NAME_SELINUX)) 2772 return selinux_inode_setotherxattr(dentry, name); 2773 2774 sbsec = inode->i_sb->s_security; 2775 if (!(sbsec->flags & SE_SBLABELSUPP)) 2776 return -EOPNOTSUPP; 2777 2778 if (!is_owner_or_cap(inode)) 2779 return -EPERM; 2780 2781 AVC_AUDIT_DATA_INIT(&ad, FS); 2782 ad.u.fs.path.dentry = dentry; 2783 2784 rc = avc_has_perm(sid, isec->sid, isec->sclass, 2785 FILE__RELABELFROM, &ad); 2786 if (rc) 2787 return rc; 2788 2789 rc = security_context_to_sid(value, size, &newsid); 2790 if (rc == -EINVAL) { 2791 if (!capable(CAP_MAC_ADMIN)) 2792 return rc; 2793 rc = security_context_to_sid_force(value, size, &newsid); 2794 } 2795 if (rc) 2796 return rc; 2797 2798 rc = avc_has_perm(sid, newsid, isec->sclass, 2799 FILE__RELABELTO, &ad); 2800 if (rc) 2801 return rc; 2802 2803 rc = security_validate_transition(isec->sid, newsid, sid, 2804 isec->sclass); 2805 if (rc) 2806 return rc; 2807 2808 return avc_has_perm(newsid, 2809 sbsec->sid, 2810 SECCLASS_FILESYSTEM, 2811 FILESYSTEM__ASSOCIATE, 2812 &ad); 2813 } 2814 2815 static void selinux_inode_post_setxattr(struct dentry *dentry, const char *name, 2816 const void *value, size_t size, 2817 int flags) 2818 { 2819 struct inode *inode = dentry->d_inode; 2820 struct inode_security_struct *isec = inode->i_security; 2821 u32 newsid; 2822 int rc; 2823 2824 if (strcmp(name, XATTR_NAME_SELINUX)) { 2825 /* Not an attribute we recognize, so nothing to do. */ 2826 return; 2827 } 2828 2829 rc = security_context_to_sid_force(value, size, &newsid); 2830 if (rc) { 2831 printk(KERN_ERR "SELinux: unable to map context to SID" 2832 "for (%s, %lu), rc=%d\n", 2833 inode->i_sb->s_id, inode->i_ino, -rc); 2834 return; 2835 } 2836 2837 isec->sid = newsid; 2838 return; 2839 } 2840 2841 static int selinux_inode_getxattr(struct dentry *dentry, const char *name) 2842 { 2843 const struct cred *cred = current_cred(); 2844 2845 return dentry_has_perm(cred, NULL, dentry, FILE__GETATTR); 2846 } 2847 2848 static int selinux_inode_listxattr(struct dentry *dentry) 2849 { 2850 const struct cred *cred = current_cred(); 2851 2852 return dentry_has_perm(cred, NULL, dentry, FILE__GETATTR); 2853 } 2854 2855 static int selinux_inode_removexattr(struct dentry *dentry, const char *name) 2856 { 2857 if (strcmp(name, XATTR_NAME_SELINUX)) 2858 return selinux_inode_setotherxattr(dentry, name); 2859 2860 /* No one is allowed to remove a SELinux security label. 2861 You can change the label, but all data must be labeled. */ 2862 return -EACCES; 2863 } 2864 2865 /* 2866 * Copy the inode security context value to the user. 2867 * 2868 * Permission check is handled by selinux_inode_getxattr hook. 2869 */ 2870 static int selinux_inode_getsecurity(const struct inode *inode, const char *name, void **buffer, bool alloc) 2871 { 2872 u32 size; 2873 int error; 2874 char *context = NULL; 2875 struct inode_security_struct *isec = inode->i_security; 2876 2877 if (strcmp(name, XATTR_SELINUX_SUFFIX)) 2878 return -EOPNOTSUPP; 2879 2880 /* 2881 * If the caller has CAP_MAC_ADMIN, then get the raw context 2882 * value even if it is not defined by current policy; otherwise, 2883 * use the in-core value under current policy. 2884 * Use the non-auditing forms of the permission checks since 2885 * getxattr may be called by unprivileged processes commonly 2886 * and lack of permission just means that we fall back to the 2887 * in-core context value, not a denial. 2888 */ 2889 error = selinux_capable(current, current_cred(), CAP_MAC_ADMIN, 2890 SECURITY_CAP_NOAUDIT); 2891 if (!error) 2892 error = security_sid_to_context_force(isec->sid, &context, 2893 &size); 2894 else 2895 error = security_sid_to_context(isec->sid, &context, &size); 2896 if (error) 2897 return error; 2898 error = size; 2899 if (alloc) { 2900 *buffer = context; 2901 goto out_nofree; 2902 } 2903 kfree(context); 2904 out_nofree: 2905 return error; 2906 } 2907 2908 static int selinux_inode_setsecurity(struct inode *inode, const char *name, 2909 const void *value, size_t size, int flags) 2910 { 2911 struct inode_security_struct *isec = inode->i_security; 2912 u32 newsid; 2913 int rc; 2914 2915 if (strcmp(name, XATTR_SELINUX_SUFFIX)) 2916 return -EOPNOTSUPP; 2917 2918 if (!value || !size) 2919 return -EACCES; 2920 2921 rc = security_context_to_sid((void *)value, size, &newsid); 2922 if (rc) 2923 return rc; 2924 2925 isec->sid = newsid; 2926 return 0; 2927 } 2928 2929 static int selinux_inode_listsecurity(struct inode *inode, char *buffer, size_t buffer_size) 2930 { 2931 const int len = sizeof(XATTR_NAME_SELINUX); 2932 if (buffer && len <= buffer_size) 2933 memcpy(buffer, XATTR_NAME_SELINUX, len); 2934 return len; 2935 } 2936 2937 static void selinux_inode_getsecid(const struct inode *inode, u32 *secid) 2938 { 2939 struct inode_security_struct *isec = inode->i_security; 2940 *secid = isec->sid; 2941 } 2942 2943 /* file security operations */ 2944 2945 static int selinux_revalidate_file_permission(struct file *file, int mask) 2946 { 2947 const struct cred *cred = current_cred(); 2948 int rc; 2949 struct inode *inode = file->f_path.dentry->d_inode; 2950 2951 if (!mask) { 2952 /* No permission to check. Existence test. */ 2953 return 0; 2954 } 2955 2956 /* file_mask_to_av won't add FILE__WRITE if MAY_APPEND is set */ 2957 if ((file->f_flags & O_APPEND) && (mask & MAY_WRITE)) 2958 mask |= MAY_APPEND; 2959 2960 rc = file_has_perm(cred, file, 2961 file_mask_to_av(inode->i_mode, mask)); 2962 if (rc) 2963 return rc; 2964 2965 return selinux_netlbl_inode_permission(inode, mask); 2966 } 2967 2968 static int selinux_file_permission(struct file *file, int mask) 2969 { 2970 struct inode *inode = file->f_path.dentry->d_inode; 2971 struct file_security_struct *fsec = file->f_security; 2972 struct inode_security_struct *isec = inode->i_security; 2973 u32 sid = current_sid(); 2974 2975 if (!mask) { 2976 /* No permission to check. Existence test. */ 2977 return 0; 2978 } 2979 2980 if (sid == fsec->sid && fsec->isid == isec->sid 2981 && fsec->pseqno == avc_policy_seqno()) 2982 return selinux_netlbl_inode_permission(inode, mask); 2983 2984 return selinux_revalidate_file_permission(file, mask); 2985 } 2986 2987 static int selinux_file_alloc_security(struct file *file) 2988 { 2989 return file_alloc_security(file); 2990 } 2991 2992 static void selinux_file_free_security(struct file *file) 2993 { 2994 file_free_security(file); 2995 } 2996 2997 static int selinux_file_ioctl(struct file *file, unsigned int cmd, 2998 unsigned long arg) 2999 { 3000 const struct cred *cred = current_cred(); 3001 u32 av = 0; 3002 3003 if (_IOC_DIR(cmd) & _IOC_WRITE) 3004 av |= FILE__WRITE; 3005 if (_IOC_DIR(cmd) & _IOC_READ) 3006 av |= FILE__READ; 3007 if (!av) 3008 av = FILE__IOCTL; 3009 3010 return file_has_perm(cred, file, av); 3011 } 3012 3013 static int file_map_prot_check(struct file *file, unsigned long prot, int shared) 3014 { 3015 const struct cred *cred = current_cred(); 3016 int rc = 0; 3017 3018 #ifndef CONFIG_PPC32 3019 if ((prot & PROT_EXEC) && (!file || (!shared && (prot & PROT_WRITE)))) { 3020 /* 3021 * We are making executable an anonymous mapping or a 3022 * private file mapping that will also be writable. 3023 * This has an additional check. 3024 */ 3025 rc = cred_has_perm(cred, cred, PROCESS__EXECMEM); 3026 if (rc) 3027 goto error; 3028 } 3029 #endif 3030 3031 if (file) { 3032 /* read access is always possible with a mapping */ 3033 u32 av = FILE__READ; 3034 3035 /* write access only matters if the mapping is shared */ 3036 if (shared && (prot & PROT_WRITE)) 3037 av |= FILE__WRITE; 3038 3039 if (prot & PROT_EXEC) 3040 av |= FILE__EXECUTE; 3041 3042 return file_has_perm(cred, file, av); 3043 } 3044 3045 error: 3046 return rc; 3047 } 3048 3049 static int selinux_file_mmap(struct file *file, unsigned long reqprot, 3050 unsigned long prot, unsigned long flags, 3051 unsigned long addr, unsigned long addr_only) 3052 { 3053 int rc = 0; 3054 u32 sid = current_sid(); 3055 3056 if (addr < mmap_min_addr) 3057 rc = avc_has_perm(sid, sid, SECCLASS_MEMPROTECT, 3058 MEMPROTECT__MMAP_ZERO, NULL); 3059 if (rc || addr_only) 3060 return rc; 3061 3062 if (selinux_checkreqprot) 3063 prot = reqprot; 3064 3065 return file_map_prot_check(file, prot, 3066 (flags & MAP_TYPE) == MAP_SHARED); 3067 } 3068 3069 static int selinux_file_mprotect(struct vm_area_struct *vma, 3070 unsigned long reqprot, 3071 unsigned long prot) 3072 { 3073 const struct cred *cred = current_cred(); 3074 3075 if (selinux_checkreqprot) 3076 prot = reqprot; 3077 3078 #ifndef CONFIG_PPC32 3079 if ((prot & PROT_EXEC) && !(vma->vm_flags & VM_EXEC)) { 3080 int rc = 0; 3081 if (vma->vm_start >= vma->vm_mm->start_brk && 3082 vma->vm_end <= vma->vm_mm->brk) { 3083 rc = cred_has_perm(cred, cred, PROCESS__EXECHEAP); 3084 } else if (!vma->vm_file && 3085 vma->vm_start <= vma->vm_mm->start_stack && 3086 vma->vm_end >= vma->vm_mm->start_stack) { 3087 rc = current_has_perm(current, PROCESS__EXECSTACK); 3088 } else if (vma->vm_file && vma->anon_vma) { 3089 /* 3090 * We are making executable a file mapping that has 3091 * had some COW done. Since pages might have been 3092 * written, check ability to execute the possibly 3093 * modified content. This typically should only 3094 * occur for text relocations. 3095 */ 3096 rc = file_has_perm(cred, vma->vm_file, FILE__EXECMOD); 3097 } 3098 if (rc) 3099 return rc; 3100 } 3101 #endif 3102 3103 return file_map_prot_check(vma->vm_file, prot, vma->vm_flags&VM_SHARED); 3104 } 3105 3106 static int selinux_file_lock(struct file *file, unsigned int cmd) 3107 { 3108 const struct cred *cred = current_cred(); 3109 3110 return file_has_perm(cred, file, FILE__LOCK); 3111 } 3112 3113 static int selinux_file_fcntl(struct file *file, unsigned int cmd, 3114 unsigned long arg) 3115 { 3116 const struct cred *cred = current_cred(); 3117 int err = 0; 3118 3119 switch (cmd) { 3120 case F_SETFL: 3121 if (!file->f_path.dentry || !file->f_path.dentry->d_inode) { 3122 err = -EINVAL; 3123 break; 3124 } 3125 3126 if ((file->f_flags & O_APPEND) && !(arg & O_APPEND)) { 3127 err = file_has_perm(cred, file, FILE__WRITE); 3128 break; 3129 } 3130 /* fall through */ 3131 case F_SETOWN: 3132 case F_SETSIG: 3133 case F_GETFL: 3134 case F_GETOWN: 3135 case F_GETSIG: 3136 /* Just check FD__USE permission */ 3137 err = file_has_perm(cred, file, 0); 3138 break; 3139 case F_GETLK: 3140 case F_SETLK: 3141 case F_SETLKW: 3142 #if BITS_PER_LONG == 32 3143 case F_GETLK64: 3144 case F_SETLK64: 3145 case F_SETLKW64: 3146 #endif 3147 if (!file->f_path.dentry || !file->f_path.dentry->d_inode) { 3148 err = -EINVAL; 3149 break; 3150 } 3151 err = file_has_perm(cred, file, FILE__LOCK); 3152 break; 3153 } 3154 3155 return err; 3156 } 3157 3158 static int selinux_file_set_fowner(struct file *file) 3159 { 3160 struct file_security_struct *fsec; 3161 3162 fsec = file->f_security; 3163 fsec->fown_sid = current_sid(); 3164 3165 return 0; 3166 } 3167 3168 static int selinux_file_send_sigiotask(struct task_struct *tsk, 3169 struct fown_struct *fown, int signum) 3170 { 3171 struct file *file; 3172 u32 sid = current_sid(); 3173 u32 perm; 3174 struct file_security_struct *fsec; 3175 3176 /* struct fown_struct is never outside the context of a struct file */ 3177 file = container_of(fown, struct file, f_owner); 3178 3179 fsec = file->f_security; 3180 3181 if (!signum) 3182 perm = signal_to_av(SIGIO); /* as per send_sigio_to_task */ 3183 else 3184 perm = signal_to_av(signum); 3185 3186 return avc_has_perm(fsec->fown_sid, sid, 3187 SECCLASS_PROCESS, perm, NULL); 3188 } 3189 3190 static int selinux_file_receive(struct file *file) 3191 { 3192 const struct cred *cred = current_cred(); 3193 3194 return file_has_perm(cred, file, file_to_av(file)); 3195 } 3196 3197 static int selinux_dentry_open(struct file *file, const struct cred *cred) 3198 { 3199 struct file_security_struct *fsec; 3200 struct inode *inode; 3201 struct inode_security_struct *isec; 3202 3203 inode = file->f_path.dentry->d_inode; 3204 fsec = file->f_security; 3205 isec = inode->i_security; 3206 /* 3207 * Save inode label and policy sequence number 3208 * at open-time so that selinux_file_permission 3209 * can determine whether revalidation is necessary. 3210 * Task label is already saved in the file security 3211 * struct as its SID. 3212 */ 3213 fsec->isid = isec->sid; 3214 fsec->pseqno = avc_policy_seqno(); 3215 /* 3216 * Since the inode label or policy seqno may have changed 3217 * between the selinux_inode_permission check and the saving 3218 * of state above, recheck that access is still permitted. 3219 * Otherwise, access might never be revalidated against the 3220 * new inode label or new policy. 3221 * This check is not redundant - do not remove. 3222 */ 3223 return inode_has_perm(cred, inode, open_file_to_av(file), NULL); 3224 } 3225 3226 /* task security operations */ 3227 3228 static int selinux_task_create(unsigned long clone_flags) 3229 { 3230 return current_has_perm(current, PROCESS__FORK); 3231 } 3232 3233 /* 3234 * detach and free the LSM part of a set of credentials 3235 */ 3236 static void selinux_cred_free(struct cred *cred) 3237 { 3238 struct task_security_struct *tsec = cred->security; 3239 cred->security = NULL; 3240 kfree(tsec); 3241 } 3242 3243 /* 3244 * prepare a new set of credentials for modification 3245 */ 3246 static int selinux_cred_prepare(struct cred *new, const struct cred *old, 3247 gfp_t gfp) 3248 { 3249 const struct task_security_struct *old_tsec; 3250 struct task_security_struct *tsec; 3251 3252 old_tsec = old->security; 3253 3254 tsec = kmemdup(old_tsec, sizeof(struct task_security_struct), gfp); 3255 if (!tsec) 3256 return -ENOMEM; 3257 3258 new->security = tsec; 3259 return 0; 3260 } 3261 3262 /* 3263 * set the security data for a kernel service 3264 * - all the creation contexts are set to unlabelled 3265 */ 3266 static int selinux_kernel_act_as(struct cred *new, u32 secid) 3267 { 3268 struct task_security_struct *tsec = new->security; 3269 u32 sid = current_sid(); 3270 int ret; 3271 3272 ret = avc_has_perm(sid, secid, 3273 SECCLASS_KERNEL_SERVICE, 3274 KERNEL_SERVICE__USE_AS_OVERRIDE, 3275 NULL); 3276 if (ret == 0) { 3277 tsec->sid = secid; 3278 tsec->create_sid = 0; 3279 tsec->keycreate_sid = 0; 3280 tsec->sockcreate_sid = 0; 3281 } 3282 return ret; 3283 } 3284 3285 /* 3286 * set the file creation context in a security record to the same as the 3287 * objective context of the specified inode 3288 */ 3289 static int selinux_kernel_create_files_as(struct cred *new, struct inode *inode) 3290 { 3291 struct inode_security_struct *isec = inode->i_security; 3292 struct task_security_struct *tsec = new->security; 3293 u32 sid = current_sid(); 3294 int ret; 3295 3296 ret = avc_has_perm(sid, isec->sid, 3297 SECCLASS_KERNEL_SERVICE, 3298 KERNEL_SERVICE__CREATE_FILES_AS, 3299 NULL); 3300 3301 if (ret == 0) 3302 tsec->create_sid = isec->sid; 3303 return 0; 3304 } 3305 3306 static int selinux_task_setpgid(struct task_struct *p, pid_t pgid) 3307 { 3308 return current_has_perm(p, PROCESS__SETPGID); 3309 } 3310 3311 static int selinux_task_getpgid(struct task_struct *p) 3312 { 3313 return current_has_perm(p, PROCESS__GETPGID); 3314 } 3315 3316 static int selinux_task_getsid(struct task_struct *p) 3317 { 3318 return current_has_perm(p, PROCESS__GETSESSION); 3319 } 3320 3321 static void selinux_task_getsecid(struct task_struct *p, u32 *secid) 3322 { 3323 *secid = task_sid(p); 3324 } 3325 3326 static int selinux_task_setnice(struct task_struct *p, int nice) 3327 { 3328 int rc; 3329 3330 rc = cap_task_setnice(p, nice); 3331 if (rc) 3332 return rc; 3333 3334 return current_has_perm(p, PROCESS__SETSCHED); 3335 } 3336 3337 static int selinux_task_setioprio(struct task_struct *p, int ioprio) 3338 { 3339 int rc; 3340 3341 rc = cap_task_setioprio(p, ioprio); 3342 if (rc) 3343 return rc; 3344 3345 return current_has_perm(p, PROCESS__SETSCHED); 3346 } 3347 3348 static int selinux_task_getioprio(struct task_struct *p) 3349 { 3350 return current_has_perm(p, PROCESS__GETSCHED); 3351 } 3352 3353 static int selinux_task_setrlimit(unsigned int resource, struct rlimit *new_rlim) 3354 { 3355 struct rlimit *old_rlim = current->signal->rlim + resource; 3356 3357 /* Control the ability to change the hard limit (whether 3358 lowering or raising it), so that the hard limit can 3359 later be used as a safe reset point for the soft limit 3360 upon context transitions. See selinux_bprm_committing_creds. */ 3361 if (old_rlim->rlim_max != new_rlim->rlim_max) 3362 return current_has_perm(current, PROCESS__SETRLIMIT); 3363 3364 return 0; 3365 } 3366 3367 static int selinux_task_setscheduler(struct task_struct *p, int policy, struct sched_param *lp) 3368 { 3369 int rc; 3370 3371 rc = cap_task_setscheduler(p, policy, lp); 3372 if (rc) 3373 return rc; 3374 3375 return current_has_perm(p, PROCESS__SETSCHED); 3376 } 3377 3378 static int selinux_task_getscheduler(struct task_struct *p) 3379 { 3380 return current_has_perm(p, PROCESS__GETSCHED); 3381 } 3382 3383 static int selinux_task_movememory(struct task_struct *p) 3384 { 3385 return current_has_perm(p, PROCESS__SETSCHED); 3386 } 3387 3388 static int selinux_task_kill(struct task_struct *p, struct siginfo *info, 3389 int sig, u32 secid) 3390 { 3391 u32 perm; 3392 int rc; 3393 3394 if (!sig) 3395 perm = PROCESS__SIGNULL; /* null signal; existence test */ 3396 else 3397 perm = signal_to_av(sig); 3398 if (secid) 3399 rc = avc_has_perm(secid, task_sid(p), 3400 SECCLASS_PROCESS, perm, NULL); 3401 else 3402 rc = current_has_perm(p, perm); 3403 return rc; 3404 } 3405 3406 static int selinux_task_wait(struct task_struct *p) 3407 { 3408 return task_has_perm(p, current, PROCESS__SIGCHLD); 3409 } 3410 3411 static void selinux_task_to_inode(struct task_struct *p, 3412 struct inode *inode) 3413 { 3414 struct inode_security_struct *isec = inode->i_security; 3415 u32 sid = task_sid(p); 3416 3417 isec->sid = sid; 3418 isec->initialized = 1; 3419 } 3420 3421 /* Returns error only if unable to parse addresses */ 3422 static int selinux_parse_skb_ipv4(struct sk_buff *skb, 3423 struct avc_audit_data *ad, u8 *proto) 3424 { 3425 int offset, ihlen, ret = -EINVAL; 3426 struct iphdr _iph, *ih; 3427 3428 offset = skb_network_offset(skb); 3429 ih = skb_header_pointer(skb, offset, sizeof(_iph), &_iph); 3430 if (ih == NULL) 3431 goto out; 3432 3433 ihlen = ih->ihl * 4; 3434 if (ihlen < sizeof(_iph)) 3435 goto out; 3436 3437 ad->u.net.v4info.saddr = ih->saddr; 3438 ad->u.net.v4info.daddr = ih->daddr; 3439 ret = 0; 3440 3441 if (proto) 3442 *proto = ih->protocol; 3443 3444 switch (ih->protocol) { 3445 case IPPROTO_TCP: { 3446 struct tcphdr _tcph, *th; 3447 3448 if (ntohs(ih->frag_off) & IP_OFFSET) 3449 break; 3450 3451 offset += ihlen; 3452 th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph); 3453 if (th == NULL) 3454 break; 3455 3456 ad->u.net.sport = th->source; 3457 ad->u.net.dport = th->dest; 3458 break; 3459 } 3460 3461 case IPPROTO_UDP: { 3462 struct udphdr _udph, *uh; 3463 3464 if (ntohs(ih->frag_off) & IP_OFFSET) 3465 break; 3466 3467 offset += ihlen; 3468 uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph); 3469 if (uh == NULL) 3470 break; 3471 3472 ad->u.net.sport = uh->source; 3473 ad->u.net.dport = uh->dest; 3474 break; 3475 } 3476 3477 case IPPROTO_DCCP: { 3478 struct dccp_hdr _dccph, *dh; 3479 3480 if (ntohs(ih->frag_off) & IP_OFFSET) 3481 break; 3482 3483 offset += ihlen; 3484 dh = skb_header_pointer(skb, offset, sizeof(_dccph), &_dccph); 3485 if (dh == NULL) 3486 break; 3487 3488 ad->u.net.sport = dh->dccph_sport; 3489 ad->u.net.dport = dh->dccph_dport; 3490 break; 3491 } 3492 3493 default: 3494 break; 3495 } 3496 out: 3497 return ret; 3498 } 3499 3500 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE) 3501 3502 /* Returns error only if unable to parse addresses */ 3503 static int selinux_parse_skb_ipv6(struct sk_buff *skb, 3504 struct avc_audit_data *ad, u8 *proto) 3505 { 3506 u8 nexthdr; 3507 int ret = -EINVAL, offset; 3508 struct ipv6hdr _ipv6h, *ip6; 3509 3510 offset = skb_network_offset(skb); 3511 ip6 = skb_header_pointer(skb, offset, sizeof(_ipv6h), &_ipv6h); 3512 if (ip6 == NULL) 3513 goto out; 3514 3515 ipv6_addr_copy(&ad->u.net.v6info.saddr, &ip6->saddr); 3516 ipv6_addr_copy(&ad->u.net.v6info.daddr, &ip6->daddr); 3517 ret = 0; 3518 3519 nexthdr = ip6->nexthdr; 3520 offset += sizeof(_ipv6h); 3521 offset = ipv6_skip_exthdr(skb, offset, &nexthdr); 3522 if (offset < 0) 3523 goto out; 3524 3525 if (proto) 3526 *proto = nexthdr; 3527 3528 switch (nexthdr) { 3529 case IPPROTO_TCP: { 3530 struct tcphdr _tcph, *th; 3531 3532 th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph); 3533 if (th == NULL) 3534 break; 3535 3536 ad->u.net.sport = th->source; 3537 ad->u.net.dport = th->dest; 3538 break; 3539 } 3540 3541 case IPPROTO_UDP: { 3542 struct udphdr _udph, *uh; 3543 3544 uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph); 3545 if (uh == NULL) 3546 break; 3547 3548 ad->u.net.sport = uh->source; 3549 ad->u.net.dport = uh->dest; 3550 break; 3551 } 3552 3553 case IPPROTO_DCCP: { 3554 struct dccp_hdr _dccph, *dh; 3555 3556 dh = skb_header_pointer(skb, offset, sizeof(_dccph), &_dccph); 3557 if (dh == NULL) 3558 break; 3559 3560 ad->u.net.sport = dh->dccph_sport; 3561 ad->u.net.dport = dh->dccph_dport; 3562 break; 3563 } 3564 3565 /* includes fragments */ 3566 default: 3567 break; 3568 } 3569 out: 3570 return ret; 3571 } 3572 3573 #endif /* IPV6 */ 3574 3575 static int selinux_parse_skb(struct sk_buff *skb, struct avc_audit_data *ad, 3576 char **_addrp, int src, u8 *proto) 3577 { 3578 char *addrp; 3579 int ret; 3580 3581 switch (ad->u.net.family) { 3582 case PF_INET: 3583 ret = selinux_parse_skb_ipv4(skb, ad, proto); 3584 if (ret) 3585 goto parse_error; 3586 addrp = (char *)(src ? &ad->u.net.v4info.saddr : 3587 &ad->u.net.v4info.daddr); 3588 goto okay; 3589 3590 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE) 3591 case PF_INET6: 3592 ret = selinux_parse_skb_ipv6(skb, ad, proto); 3593 if (ret) 3594 goto parse_error; 3595 addrp = (char *)(src ? &ad->u.net.v6info.saddr : 3596 &ad->u.net.v6info.daddr); 3597 goto okay; 3598 #endif /* IPV6 */ 3599 default: 3600 addrp = NULL; 3601 goto okay; 3602 } 3603 3604 parse_error: 3605 printk(KERN_WARNING 3606 "SELinux: failure in selinux_parse_skb()," 3607 " unable to parse packet\n"); 3608 return ret; 3609 3610 okay: 3611 if (_addrp) 3612 *_addrp = addrp; 3613 return 0; 3614 } 3615 3616 /** 3617 * selinux_skb_peerlbl_sid - Determine the peer label of a packet 3618 * @skb: the packet 3619 * @family: protocol family 3620 * @sid: the packet's peer label SID 3621 * 3622 * Description: 3623 * Check the various different forms of network peer labeling and determine 3624 * the peer label/SID for the packet; most of the magic actually occurs in 3625 * the security server function security_net_peersid_cmp(). The function 3626 * returns zero if the value in @sid is valid (although it may be SECSID_NULL) 3627 * or -EACCES if @sid is invalid due to inconsistencies with the different 3628 * peer labels. 3629 * 3630 */ 3631 static int selinux_skb_peerlbl_sid(struct sk_buff *skb, u16 family, u32 *sid) 3632 { 3633 int err; 3634 u32 xfrm_sid; 3635 u32 nlbl_sid; 3636 u32 nlbl_type; 3637 3638 selinux_skb_xfrm_sid(skb, &xfrm_sid); 3639 selinux_netlbl_skbuff_getsid(skb, family, &nlbl_type, &nlbl_sid); 3640 3641 err = security_net_peersid_resolve(nlbl_sid, nlbl_type, xfrm_sid, sid); 3642 if (unlikely(err)) { 3643 printk(KERN_WARNING 3644 "SELinux: failure in selinux_skb_peerlbl_sid()," 3645 " unable to determine packet's peer label\n"); 3646 return -EACCES; 3647 } 3648 3649 return 0; 3650 } 3651 3652 /* socket security operations */ 3653 static int socket_has_perm(struct task_struct *task, struct socket *sock, 3654 u32 perms) 3655 { 3656 struct inode_security_struct *isec; 3657 struct avc_audit_data ad; 3658 u32 sid; 3659 int err = 0; 3660 3661 isec = SOCK_INODE(sock)->i_security; 3662 3663 if (isec->sid == SECINITSID_KERNEL) 3664 goto out; 3665 sid = task_sid(task); 3666 3667 AVC_AUDIT_DATA_INIT(&ad, NET); 3668 ad.u.net.sk = sock->sk; 3669 err = avc_has_perm(sid, isec->sid, isec->sclass, perms, &ad); 3670 3671 out: 3672 return err; 3673 } 3674 3675 static int selinux_socket_create(int family, int type, 3676 int protocol, int kern) 3677 { 3678 const struct cred *cred = current_cred(); 3679 const struct task_security_struct *tsec = cred->security; 3680 u32 sid, newsid; 3681 u16 secclass; 3682 int err = 0; 3683 3684 if (kern) 3685 goto out; 3686 3687 sid = tsec->sid; 3688 newsid = tsec->sockcreate_sid ?: sid; 3689 3690 secclass = socket_type_to_security_class(family, type, protocol); 3691 err = avc_has_perm(sid, newsid, secclass, SOCKET__CREATE, NULL); 3692 3693 out: 3694 return err; 3695 } 3696 3697 static int selinux_socket_post_create(struct socket *sock, int family, 3698 int type, int protocol, int kern) 3699 { 3700 const struct cred *cred = current_cred(); 3701 const struct task_security_struct *tsec = cred->security; 3702 struct inode_security_struct *isec; 3703 struct sk_security_struct *sksec; 3704 u32 sid, newsid; 3705 int err = 0; 3706 3707 sid = tsec->sid; 3708 newsid = tsec->sockcreate_sid; 3709 3710 isec = SOCK_INODE(sock)->i_security; 3711 3712 if (kern) 3713 isec->sid = SECINITSID_KERNEL; 3714 else if (newsid) 3715 isec->sid = newsid; 3716 else 3717 isec->sid = sid; 3718 3719 isec->sclass = socket_type_to_security_class(family, type, protocol); 3720 isec->initialized = 1; 3721 3722 if (sock->sk) { 3723 sksec = sock->sk->sk_security; 3724 sksec->sid = isec->sid; 3725 sksec->sclass = isec->sclass; 3726 err = selinux_netlbl_socket_post_create(sock); 3727 } 3728 3729 return err; 3730 } 3731 3732 /* Range of port numbers used to automatically bind. 3733 Need to determine whether we should perform a name_bind 3734 permission check between the socket and the port number. */ 3735 3736 static int selinux_socket_bind(struct socket *sock, struct sockaddr *address, int addrlen) 3737 { 3738 u16 family; 3739 int err; 3740 3741 err = socket_has_perm(current, sock, SOCKET__BIND); 3742 if (err) 3743 goto out; 3744 3745 /* 3746 * If PF_INET or PF_INET6, check name_bind permission for the port. 3747 * Multiple address binding for SCTP is not supported yet: we just 3748 * check the first address now. 3749 */ 3750 family = sock->sk->sk_family; 3751 if (family == PF_INET || family == PF_INET6) { 3752 char *addrp; 3753 struct inode_security_struct *isec; 3754 struct avc_audit_data ad; 3755 struct sockaddr_in *addr4 = NULL; 3756 struct sockaddr_in6 *addr6 = NULL; 3757 unsigned short snum; 3758 struct sock *sk = sock->sk; 3759 u32 sid, node_perm; 3760 3761 isec = SOCK_INODE(sock)->i_security; 3762 3763 if (family == PF_INET) { 3764 addr4 = (struct sockaddr_in *)address; 3765 snum = ntohs(addr4->sin_port); 3766 addrp = (char *)&addr4->sin_addr.s_addr; 3767 } else { 3768 addr6 = (struct sockaddr_in6 *)address; 3769 snum = ntohs(addr6->sin6_port); 3770 addrp = (char *)&addr6->sin6_addr.s6_addr; 3771 } 3772 3773 if (snum) { 3774 int low, high; 3775 3776 inet_get_local_port_range(&low, &high); 3777 3778 if (snum < max(PROT_SOCK, low) || snum > high) { 3779 err = sel_netport_sid(sk->sk_protocol, 3780 snum, &sid); 3781 if (err) 3782 goto out; 3783 AVC_AUDIT_DATA_INIT(&ad, NET); 3784 ad.u.net.sport = htons(snum); 3785 ad.u.net.family = family; 3786 err = avc_has_perm(isec->sid, sid, 3787 isec->sclass, 3788 SOCKET__NAME_BIND, &ad); 3789 if (err) 3790 goto out; 3791 } 3792 } 3793 3794 switch (isec->sclass) { 3795 case SECCLASS_TCP_SOCKET: 3796 node_perm = TCP_SOCKET__NODE_BIND; 3797 break; 3798 3799 case SECCLASS_UDP_SOCKET: 3800 node_perm = UDP_SOCKET__NODE_BIND; 3801 break; 3802 3803 case SECCLASS_DCCP_SOCKET: 3804 node_perm = DCCP_SOCKET__NODE_BIND; 3805 break; 3806 3807 default: 3808 node_perm = RAWIP_SOCKET__NODE_BIND; 3809 break; 3810 } 3811 3812 err = sel_netnode_sid(addrp, family, &sid); 3813 if (err) 3814 goto out; 3815 3816 AVC_AUDIT_DATA_INIT(&ad, NET); 3817 ad.u.net.sport = htons(snum); 3818 ad.u.net.family = family; 3819 3820 if (family == PF_INET) 3821 ad.u.net.v4info.saddr = addr4->sin_addr.s_addr; 3822 else 3823 ipv6_addr_copy(&ad.u.net.v6info.saddr, &addr6->sin6_addr); 3824 3825 err = avc_has_perm(isec->sid, sid, 3826 isec->sclass, node_perm, &ad); 3827 if (err) 3828 goto out; 3829 } 3830 out: 3831 return err; 3832 } 3833 3834 static int selinux_socket_connect(struct socket *sock, struct sockaddr *address, int addrlen) 3835 { 3836 struct sock *sk = sock->sk; 3837 struct inode_security_struct *isec; 3838 int err; 3839 3840 err = socket_has_perm(current, sock, SOCKET__CONNECT); 3841 if (err) 3842 return err; 3843 3844 /* 3845 * If a TCP or DCCP socket, check name_connect permission for the port. 3846 */ 3847 isec = SOCK_INODE(sock)->i_security; 3848 if (isec->sclass == SECCLASS_TCP_SOCKET || 3849 isec->sclass == SECCLASS_DCCP_SOCKET) { 3850 struct avc_audit_data ad; 3851 struct sockaddr_in *addr4 = NULL; 3852 struct sockaddr_in6 *addr6 = NULL; 3853 unsigned short snum; 3854 u32 sid, perm; 3855 3856 if (sk->sk_family == PF_INET) { 3857 addr4 = (struct sockaddr_in *)address; 3858 if (addrlen < sizeof(struct sockaddr_in)) 3859 return -EINVAL; 3860 snum = ntohs(addr4->sin_port); 3861 } else { 3862 addr6 = (struct sockaddr_in6 *)address; 3863 if (addrlen < SIN6_LEN_RFC2133) 3864 return -EINVAL; 3865 snum = ntohs(addr6->sin6_port); 3866 } 3867 3868 err = sel_netport_sid(sk->sk_protocol, snum, &sid); 3869 if (err) 3870 goto out; 3871 3872 perm = (isec->sclass == SECCLASS_TCP_SOCKET) ? 3873 TCP_SOCKET__NAME_CONNECT : DCCP_SOCKET__NAME_CONNECT; 3874 3875 AVC_AUDIT_DATA_INIT(&ad, NET); 3876 ad.u.net.dport = htons(snum); 3877 ad.u.net.family = sk->sk_family; 3878 err = avc_has_perm(isec->sid, sid, isec->sclass, perm, &ad); 3879 if (err) 3880 goto out; 3881 } 3882 3883 err = selinux_netlbl_socket_connect(sk, address); 3884 3885 out: 3886 return err; 3887 } 3888 3889 static int selinux_socket_listen(struct socket *sock, int backlog) 3890 { 3891 return socket_has_perm(current, sock, SOCKET__LISTEN); 3892 } 3893 3894 static int selinux_socket_accept(struct socket *sock, struct socket *newsock) 3895 { 3896 int err; 3897 struct inode_security_struct *isec; 3898 struct inode_security_struct *newisec; 3899 3900 err = socket_has_perm(current, sock, SOCKET__ACCEPT); 3901 if (err) 3902 return err; 3903 3904 newisec = SOCK_INODE(newsock)->i_security; 3905 3906 isec = SOCK_INODE(sock)->i_security; 3907 newisec->sclass = isec->sclass; 3908 newisec->sid = isec->sid; 3909 newisec->initialized = 1; 3910 3911 return 0; 3912 } 3913 3914 static int selinux_socket_sendmsg(struct socket *sock, struct msghdr *msg, 3915 int size) 3916 { 3917 int rc; 3918 3919 rc = socket_has_perm(current, sock, SOCKET__WRITE); 3920 if (rc) 3921 return rc; 3922 3923 return selinux_netlbl_inode_permission(SOCK_INODE(sock), MAY_WRITE); 3924 } 3925 3926 static int selinux_socket_recvmsg(struct socket *sock, struct msghdr *msg, 3927 int size, int flags) 3928 { 3929 return socket_has_perm(current, sock, SOCKET__READ); 3930 } 3931 3932 static int selinux_socket_getsockname(struct socket *sock) 3933 { 3934 return socket_has_perm(current, sock, SOCKET__GETATTR); 3935 } 3936 3937 static int selinux_socket_getpeername(struct socket *sock) 3938 { 3939 return socket_has_perm(current, sock, SOCKET__GETATTR); 3940 } 3941 3942 static int selinux_socket_setsockopt(struct socket *sock, int level, int optname) 3943 { 3944 int err; 3945 3946 err = socket_has_perm(current, sock, SOCKET__SETOPT); 3947 if (err) 3948 return err; 3949 3950 return selinux_netlbl_socket_setsockopt(sock, level, optname); 3951 } 3952 3953 static int selinux_socket_getsockopt(struct socket *sock, int level, 3954 int optname) 3955 { 3956 return socket_has_perm(current, sock, SOCKET__GETOPT); 3957 } 3958 3959 static int selinux_socket_shutdown(struct socket *sock, int how) 3960 { 3961 return socket_has_perm(current, sock, SOCKET__SHUTDOWN); 3962 } 3963 3964 static int selinux_socket_unix_stream_connect(struct socket *sock, 3965 struct socket *other, 3966 struct sock *newsk) 3967 { 3968 struct sk_security_struct *ssec; 3969 struct inode_security_struct *isec; 3970 struct inode_security_struct *other_isec; 3971 struct avc_audit_data ad; 3972 int err; 3973 3974 isec = SOCK_INODE(sock)->i_security; 3975 other_isec = SOCK_INODE(other)->i_security; 3976 3977 AVC_AUDIT_DATA_INIT(&ad, NET); 3978 ad.u.net.sk = other->sk; 3979 3980 err = avc_has_perm(isec->sid, other_isec->sid, 3981 isec->sclass, 3982 UNIX_STREAM_SOCKET__CONNECTTO, &ad); 3983 if (err) 3984 return err; 3985 3986 /* connecting socket */ 3987 ssec = sock->sk->sk_security; 3988 ssec->peer_sid = other_isec->sid; 3989 3990 /* server child socket */ 3991 ssec = newsk->sk_security; 3992 ssec->peer_sid = isec->sid; 3993 err = security_sid_mls_copy(other_isec->sid, ssec->peer_sid, &ssec->sid); 3994 3995 return err; 3996 } 3997 3998 static int selinux_socket_unix_may_send(struct socket *sock, 3999 struct socket *other) 4000 { 4001 struct inode_security_struct *isec; 4002 struct inode_security_struct *other_isec; 4003 struct avc_audit_data ad; 4004 int err; 4005 4006 isec = SOCK_INODE(sock)->i_security; 4007 other_isec = SOCK_INODE(other)->i_security; 4008 4009 AVC_AUDIT_DATA_INIT(&ad, NET); 4010 ad.u.net.sk = other->sk; 4011 4012 err = avc_has_perm(isec->sid, other_isec->sid, 4013 isec->sclass, SOCKET__SENDTO, &ad); 4014 if (err) 4015 return err; 4016 4017 return 0; 4018 } 4019 4020 static int selinux_inet_sys_rcv_skb(int ifindex, char *addrp, u16 family, 4021 u32 peer_sid, 4022 struct avc_audit_data *ad) 4023 { 4024 int err; 4025 u32 if_sid; 4026 u32 node_sid; 4027 4028 err = sel_netif_sid(ifindex, &if_sid); 4029 if (err) 4030 return err; 4031 err = avc_has_perm(peer_sid, if_sid, 4032 SECCLASS_NETIF, NETIF__INGRESS, ad); 4033 if (err) 4034 return err; 4035 4036 err = sel_netnode_sid(addrp, family, &node_sid); 4037 if (err) 4038 return err; 4039 return avc_has_perm(peer_sid, node_sid, 4040 SECCLASS_NODE, NODE__RECVFROM, ad); 4041 } 4042 4043 static int selinux_sock_rcv_skb_iptables_compat(struct sock *sk, 4044 struct sk_buff *skb, 4045 struct avc_audit_data *ad, 4046 u16 family, 4047 char *addrp) 4048 { 4049 int err; 4050 struct sk_security_struct *sksec = sk->sk_security; 4051 u16 sk_class; 4052 u32 netif_perm, node_perm, recv_perm; 4053 u32 port_sid, node_sid, if_sid, sk_sid; 4054 4055 sk_sid = sksec->sid; 4056 sk_class = sksec->sclass; 4057 4058 switch (sk_class) { 4059 case SECCLASS_UDP_SOCKET: 4060 netif_perm = NETIF__UDP_RECV; 4061 node_perm = NODE__UDP_RECV; 4062 recv_perm = UDP_SOCKET__RECV_MSG; 4063 break; 4064 case SECCLASS_TCP_SOCKET: 4065 netif_perm = NETIF__TCP_RECV; 4066 node_perm = NODE__TCP_RECV; 4067 recv_perm = TCP_SOCKET__RECV_MSG; 4068 break; 4069 case SECCLASS_DCCP_SOCKET: 4070 netif_perm = NETIF__DCCP_RECV; 4071 node_perm = NODE__DCCP_RECV; 4072 recv_perm = DCCP_SOCKET__RECV_MSG; 4073 break; 4074 default: 4075 netif_perm = NETIF__RAWIP_RECV; 4076 node_perm = NODE__RAWIP_RECV; 4077 recv_perm = 0; 4078 break; 4079 } 4080 4081 err = sel_netif_sid(skb->iif, &if_sid); 4082 if (err) 4083 return err; 4084 err = avc_has_perm(sk_sid, if_sid, SECCLASS_NETIF, netif_perm, ad); 4085 if (err) 4086 return err; 4087 4088 err = sel_netnode_sid(addrp, family, &node_sid); 4089 if (err) 4090 return err; 4091 err = avc_has_perm(sk_sid, node_sid, SECCLASS_NODE, node_perm, ad); 4092 if (err) 4093 return err; 4094 4095 if (!recv_perm) 4096 return 0; 4097 err = sel_netport_sid(sk->sk_protocol, 4098 ntohs(ad->u.net.sport), &port_sid); 4099 if (unlikely(err)) { 4100 printk(KERN_WARNING 4101 "SELinux: failure in" 4102 " selinux_sock_rcv_skb_iptables_compat()," 4103 " network port label not found\n"); 4104 return err; 4105 } 4106 return avc_has_perm(sk_sid, port_sid, sk_class, recv_perm, ad); 4107 } 4108 4109 static int selinux_sock_rcv_skb_compat(struct sock *sk, struct sk_buff *skb, 4110 u16 family) 4111 { 4112 int err = 0; 4113 struct sk_security_struct *sksec = sk->sk_security; 4114 u32 peer_sid; 4115 u32 sk_sid = sksec->sid; 4116 struct avc_audit_data ad; 4117 char *addrp; 4118 4119 AVC_AUDIT_DATA_INIT(&ad, NET); 4120 ad.u.net.netif = skb->iif; 4121 ad.u.net.family = family; 4122 err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL); 4123 if (err) 4124 return err; 4125 4126 if (selinux_compat_net) 4127 err = selinux_sock_rcv_skb_iptables_compat(sk, skb, &ad, 4128 family, addrp); 4129 else if (selinux_secmark_enabled()) 4130 err = avc_has_perm(sk_sid, skb->secmark, SECCLASS_PACKET, 4131 PACKET__RECV, &ad); 4132 if (err) 4133 return err; 4134 4135 if (selinux_policycap_netpeer) { 4136 err = selinux_skb_peerlbl_sid(skb, family, &peer_sid); 4137 if (err) 4138 return err; 4139 err = avc_has_perm(sk_sid, peer_sid, 4140 SECCLASS_PEER, PEER__RECV, &ad); 4141 if (err) 4142 selinux_netlbl_err(skb, err, 0); 4143 } else { 4144 err = selinux_netlbl_sock_rcv_skb(sksec, skb, family, &ad); 4145 if (err) 4146 return err; 4147 err = selinux_xfrm_sock_rcv_skb(sksec->sid, skb, &ad); 4148 } 4149 4150 return err; 4151 } 4152 4153 static int selinux_socket_sock_rcv_skb(struct sock *sk, struct sk_buff *skb) 4154 { 4155 int err; 4156 struct sk_security_struct *sksec = sk->sk_security; 4157 u16 family = sk->sk_family; 4158 u32 sk_sid = sksec->sid; 4159 struct avc_audit_data ad; 4160 char *addrp; 4161 u8 secmark_active; 4162 u8 peerlbl_active; 4163 4164 if (family != PF_INET && family != PF_INET6) 4165 return 0; 4166 4167 /* Handle mapped IPv4 packets arriving via IPv6 sockets */ 4168 if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP)) 4169 family = PF_INET; 4170 4171 /* If any sort of compatibility mode is enabled then handoff processing 4172 * to the selinux_sock_rcv_skb_compat() function to deal with the 4173 * special handling. We do this in an attempt to keep this function 4174 * as fast and as clean as possible. */ 4175 if (selinux_compat_net || !selinux_policycap_netpeer) 4176 return selinux_sock_rcv_skb_compat(sk, skb, family); 4177 4178 secmark_active = selinux_secmark_enabled(); 4179 peerlbl_active = netlbl_enabled() || selinux_xfrm_enabled(); 4180 if (!secmark_active && !peerlbl_active) 4181 return 0; 4182 4183 AVC_AUDIT_DATA_INIT(&ad, NET); 4184 ad.u.net.netif = skb->iif; 4185 ad.u.net.family = family; 4186 err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL); 4187 if (err) 4188 return err; 4189 4190 if (peerlbl_active) { 4191 u32 peer_sid; 4192 4193 err = selinux_skb_peerlbl_sid(skb, family, &peer_sid); 4194 if (err) 4195 return err; 4196 err = selinux_inet_sys_rcv_skb(skb->iif, addrp, family, 4197 peer_sid, &ad); 4198 if (err) { 4199 selinux_netlbl_err(skb, err, 0); 4200 return err; 4201 } 4202 err = avc_has_perm(sk_sid, peer_sid, SECCLASS_PEER, 4203 PEER__RECV, &ad); 4204 if (err) 4205 selinux_netlbl_err(skb, err, 0); 4206 } 4207 4208 if (secmark_active) { 4209 err = avc_has_perm(sk_sid, skb->secmark, SECCLASS_PACKET, 4210 PACKET__RECV, &ad); 4211 if (err) 4212 return err; 4213 } 4214 4215 return err; 4216 } 4217 4218 static int selinux_socket_getpeersec_stream(struct socket *sock, char __user *optval, 4219 int __user *optlen, unsigned len) 4220 { 4221 int err = 0; 4222 char *scontext; 4223 u32 scontext_len; 4224 struct sk_security_struct *ssec; 4225 struct inode_security_struct *isec; 4226 u32 peer_sid = SECSID_NULL; 4227 4228 isec = SOCK_INODE(sock)->i_security; 4229 4230 if (isec->sclass == SECCLASS_UNIX_STREAM_SOCKET || 4231 isec->sclass == SECCLASS_TCP_SOCKET) { 4232 ssec = sock->sk->sk_security; 4233 peer_sid = ssec->peer_sid; 4234 } 4235 if (peer_sid == SECSID_NULL) { 4236 err = -ENOPROTOOPT; 4237 goto out; 4238 } 4239 4240 err = security_sid_to_context(peer_sid, &scontext, &scontext_len); 4241 4242 if (err) 4243 goto out; 4244 4245 if (scontext_len > len) { 4246 err = -ERANGE; 4247 goto out_len; 4248 } 4249 4250 if (copy_to_user(optval, scontext, scontext_len)) 4251 err = -EFAULT; 4252 4253 out_len: 4254 if (put_user(scontext_len, optlen)) 4255 err = -EFAULT; 4256 4257 kfree(scontext); 4258 out: 4259 return err; 4260 } 4261 4262 static int selinux_socket_getpeersec_dgram(struct socket *sock, struct sk_buff *skb, u32 *secid) 4263 { 4264 u32 peer_secid = SECSID_NULL; 4265 u16 family; 4266 4267 if (skb && skb->protocol == htons(ETH_P_IP)) 4268 family = PF_INET; 4269 else if (skb && skb->protocol == htons(ETH_P_IPV6)) 4270 family = PF_INET6; 4271 else if (sock) 4272 family = sock->sk->sk_family; 4273 else 4274 goto out; 4275 4276 if (sock && family == PF_UNIX) 4277 selinux_inode_getsecid(SOCK_INODE(sock), &peer_secid); 4278 else if (skb) 4279 selinux_skb_peerlbl_sid(skb, family, &peer_secid); 4280 4281 out: 4282 *secid = peer_secid; 4283 if (peer_secid == SECSID_NULL) 4284 return -EINVAL; 4285 return 0; 4286 } 4287 4288 static int selinux_sk_alloc_security(struct sock *sk, int family, gfp_t priority) 4289 { 4290 return sk_alloc_security(sk, family, priority); 4291 } 4292 4293 static void selinux_sk_free_security(struct sock *sk) 4294 { 4295 sk_free_security(sk); 4296 } 4297 4298 static void selinux_sk_clone_security(const struct sock *sk, struct sock *newsk) 4299 { 4300 struct sk_security_struct *ssec = sk->sk_security; 4301 struct sk_security_struct *newssec = newsk->sk_security; 4302 4303 newssec->sid = ssec->sid; 4304 newssec->peer_sid = ssec->peer_sid; 4305 newssec->sclass = ssec->sclass; 4306 4307 selinux_netlbl_sk_security_reset(newssec, newsk->sk_family); 4308 } 4309 4310 static void selinux_sk_getsecid(struct sock *sk, u32 *secid) 4311 { 4312 if (!sk) 4313 *secid = SECINITSID_ANY_SOCKET; 4314 else { 4315 struct sk_security_struct *sksec = sk->sk_security; 4316 4317 *secid = sksec->sid; 4318 } 4319 } 4320 4321 static void selinux_sock_graft(struct sock *sk, struct socket *parent) 4322 { 4323 struct inode_security_struct *isec = SOCK_INODE(parent)->i_security; 4324 struct sk_security_struct *sksec = sk->sk_security; 4325 4326 if (sk->sk_family == PF_INET || sk->sk_family == PF_INET6 || 4327 sk->sk_family == PF_UNIX) 4328 isec->sid = sksec->sid; 4329 sksec->sclass = isec->sclass; 4330 } 4331 4332 static int selinux_inet_conn_request(struct sock *sk, struct sk_buff *skb, 4333 struct request_sock *req) 4334 { 4335 struct sk_security_struct *sksec = sk->sk_security; 4336 int err; 4337 u16 family = sk->sk_family; 4338 u32 newsid; 4339 u32 peersid; 4340 4341 /* handle mapped IPv4 packets arriving via IPv6 sockets */ 4342 if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP)) 4343 family = PF_INET; 4344 4345 err = selinux_skb_peerlbl_sid(skb, family, &peersid); 4346 if (err) 4347 return err; 4348 if (peersid == SECSID_NULL) { 4349 req->secid = sksec->sid; 4350 req->peer_secid = SECSID_NULL; 4351 return 0; 4352 } 4353 4354 err = security_sid_mls_copy(sksec->sid, peersid, &newsid); 4355 if (err) 4356 return err; 4357 4358 req->secid = newsid; 4359 req->peer_secid = peersid; 4360 return 0; 4361 } 4362 4363 static void selinux_inet_csk_clone(struct sock *newsk, 4364 const struct request_sock *req) 4365 { 4366 struct sk_security_struct *newsksec = newsk->sk_security; 4367 4368 newsksec->sid = req->secid; 4369 newsksec->peer_sid = req->peer_secid; 4370 /* NOTE: Ideally, we should also get the isec->sid for the 4371 new socket in sync, but we don't have the isec available yet. 4372 So we will wait until sock_graft to do it, by which 4373 time it will have been created and available. */ 4374 4375 /* We don't need to take any sort of lock here as we are the only 4376 * thread with access to newsksec */ 4377 selinux_netlbl_sk_security_reset(newsksec, req->rsk_ops->family); 4378 } 4379 4380 static void selinux_inet_conn_established(struct sock *sk, struct sk_buff *skb) 4381 { 4382 u16 family = sk->sk_family; 4383 struct sk_security_struct *sksec = sk->sk_security; 4384 4385 /* handle mapped IPv4 packets arriving via IPv6 sockets */ 4386 if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP)) 4387 family = PF_INET; 4388 4389 selinux_skb_peerlbl_sid(skb, family, &sksec->peer_sid); 4390 4391 selinux_netlbl_inet_conn_established(sk, family); 4392 } 4393 4394 static void selinux_req_classify_flow(const struct request_sock *req, 4395 struct flowi *fl) 4396 { 4397 fl->secid = req->secid; 4398 } 4399 4400 static int selinux_nlmsg_perm(struct sock *sk, struct sk_buff *skb) 4401 { 4402 int err = 0; 4403 u32 perm; 4404 struct nlmsghdr *nlh; 4405 struct socket *sock = sk->sk_socket; 4406 struct inode_security_struct *isec = SOCK_INODE(sock)->i_security; 4407 4408 if (skb->len < NLMSG_SPACE(0)) { 4409 err = -EINVAL; 4410 goto out; 4411 } 4412 nlh = nlmsg_hdr(skb); 4413 4414 err = selinux_nlmsg_lookup(isec->sclass, nlh->nlmsg_type, &perm); 4415 if (err) { 4416 if (err == -EINVAL) { 4417 audit_log(current->audit_context, GFP_KERNEL, AUDIT_SELINUX_ERR, 4418 "SELinux: unrecognized netlink message" 4419 " type=%hu for sclass=%hu\n", 4420 nlh->nlmsg_type, isec->sclass); 4421 if (!selinux_enforcing || security_get_allow_unknown()) 4422 err = 0; 4423 } 4424 4425 /* Ignore */ 4426 if (err == -ENOENT) 4427 err = 0; 4428 goto out; 4429 } 4430 4431 err = socket_has_perm(current, sock, perm); 4432 out: 4433 return err; 4434 } 4435 4436 #ifdef CONFIG_NETFILTER 4437 4438 static unsigned int selinux_ip_forward(struct sk_buff *skb, int ifindex, 4439 u16 family) 4440 { 4441 int err; 4442 char *addrp; 4443 u32 peer_sid; 4444 struct avc_audit_data ad; 4445 u8 secmark_active; 4446 u8 netlbl_active; 4447 u8 peerlbl_active; 4448 4449 if (!selinux_policycap_netpeer) 4450 return NF_ACCEPT; 4451 4452 secmark_active = selinux_secmark_enabled(); 4453 netlbl_active = netlbl_enabled(); 4454 peerlbl_active = netlbl_active || selinux_xfrm_enabled(); 4455 if (!secmark_active && !peerlbl_active) 4456 return NF_ACCEPT; 4457 4458 if (selinux_skb_peerlbl_sid(skb, family, &peer_sid) != 0) 4459 return NF_DROP; 4460 4461 AVC_AUDIT_DATA_INIT(&ad, NET); 4462 ad.u.net.netif = ifindex; 4463 ad.u.net.family = family; 4464 if (selinux_parse_skb(skb, &ad, &addrp, 1, NULL) != 0) 4465 return NF_DROP; 4466 4467 if (peerlbl_active) { 4468 err = selinux_inet_sys_rcv_skb(ifindex, addrp, family, 4469 peer_sid, &ad); 4470 if (err) { 4471 selinux_netlbl_err(skb, err, 1); 4472 return NF_DROP; 4473 } 4474 } 4475 4476 if (secmark_active) 4477 if (avc_has_perm(peer_sid, skb->secmark, 4478 SECCLASS_PACKET, PACKET__FORWARD_IN, &ad)) 4479 return NF_DROP; 4480 4481 if (netlbl_active) 4482 /* we do this in the FORWARD path and not the POST_ROUTING 4483 * path because we want to make sure we apply the necessary 4484 * labeling before IPsec is applied so we can leverage AH 4485 * protection */ 4486 if (selinux_netlbl_skbuff_setsid(skb, family, peer_sid) != 0) 4487 return NF_DROP; 4488 4489 return NF_ACCEPT; 4490 } 4491 4492 static unsigned int selinux_ipv4_forward(unsigned int hooknum, 4493 struct sk_buff *skb, 4494 const struct net_device *in, 4495 const struct net_device *out, 4496 int (*okfn)(struct sk_buff *)) 4497 { 4498 return selinux_ip_forward(skb, in->ifindex, PF_INET); 4499 } 4500 4501 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE) 4502 static unsigned int selinux_ipv6_forward(unsigned int hooknum, 4503 struct sk_buff *skb, 4504 const struct net_device *in, 4505 const struct net_device *out, 4506 int (*okfn)(struct sk_buff *)) 4507 { 4508 return selinux_ip_forward(skb, in->ifindex, PF_INET6); 4509 } 4510 #endif /* IPV6 */ 4511 4512 static unsigned int selinux_ip_output(struct sk_buff *skb, 4513 u16 family) 4514 { 4515 u32 sid; 4516 4517 if (!netlbl_enabled()) 4518 return NF_ACCEPT; 4519 4520 /* we do this in the LOCAL_OUT path and not the POST_ROUTING path 4521 * because we want to make sure we apply the necessary labeling 4522 * before IPsec is applied so we can leverage AH protection */ 4523 if (skb->sk) { 4524 struct sk_security_struct *sksec = skb->sk->sk_security; 4525 sid = sksec->sid; 4526 } else 4527 sid = SECINITSID_KERNEL; 4528 if (selinux_netlbl_skbuff_setsid(skb, family, sid) != 0) 4529 return NF_DROP; 4530 4531 return NF_ACCEPT; 4532 } 4533 4534 static unsigned int selinux_ipv4_output(unsigned int hooknum, 4535 struct sk_buff *skb, 4536 const struct net_device *in, 4537 const struct net_device *out, 4538 int (*okfn)(struct sk_buff *)) 4539 { 4540 return selinux_ip_output(skb, PF_INET); 4541 } 4542 4543 static int selinux_ip_postroute_iptables_compat(struct sock *sk, 4544 int ifindex, 4545 struct avc_audit_data *ad, 4546 u16 family, char *addrp) 4547 { 4548 int err; 4549 struct sk_security_struct *sksec = sk->sk_security; 4550 u16 sk_class; 4551 u32 netif_perm, node_perm, send_perm; 4552 u32 port_sid, node_sid, if_sid, sk_sid; 4553 4554 sk_sid = sksec->sid; 4555 sk_class = sksec->sclass; 4556 4557 switch (sk_class) { 4558 case SECCLASS_UDP_SOCKET: 4559 netif_perm = NETIF__UDP_SEND; 4560 node_perm = NODE__UDP_SEND; 4561 send_perm = UDP_SOCKET__SEND_MSG; 4562 break; 4563 case SECCLASS_TCP_SOCKET: 4564 netif_perm = NETIF__TCP_SEND; 4565 node_perm = NODE__TCP_SEND; 4566 send_perm = TCP_SOCKET__SEND_MSG; 4567 break; 4568 case SECCLASS_DCCP_SOCKET: 4569 netif_perm = NETIF__DCCP_SEND; 4570 node_perm = NODE__DCCP_SEND; 4571 send_perm = DCCP_SOCKET__SEND_MSG; 4572 break; 4573 default: 4574 netif_perm = NETIF__RAWIP_SEND; 4575 node_perm = NODE__RAWIP_SEND; 4576 send_perm = 0; 4577 break; 4578 } 4579 4580 err = sel_netif_sid(ifindex, &if_sid); 4581 if (err) 4582 return err; 4583 err = avc_has_perm(sk_sid, if_sid, SECCLASS_NETIF, netif_perm, ad); 4584 return err; 4585 4586 err = sel_netnode_sid(addrp, family, &node_sid); 4587 if (err) 4588 return err; 4589 err = avc_has_perm(sk_sid, node_sid, SECCLASS_NODE, node_perm, ad); 4590 if (err) 4591 return err; 4592 4593 if (send_perm != 0) 4594 return 0; 4595 4596 err = sel_netport_sid(sk->sk_protocol, 4597 ntohs(ad->u.net.dport), &port_sid); 4598 if (unlikely(err)) { 4599 printk(KERN_WARNING 4600 "SELinux: failure in" 4601 " selinux_ip_postroute_iptables_compat()," 4602 " network port label not found\n"); 4603 return err; 4604 } 4605 return avc_has_perm(sk_sid, port_sid, sk_class, send_perm, ad); 4606 } 4607 4608 static unsigned int selinux_ip_postroute_compat(struct sk_buff *skb, 4609 int ifindex, 4610 u16 family) 4611 { 4612 struct sock *sk = skb->sk; 4613 struct sk_security_struct *sksec; 4614 struct avc_audit_data ad; 4615 char *addrp; 4616 u8 proto; 4617 4618 if (sk == NULL) 4619 return NF_ACCEPT; 4620 sksec = sk->sk_security; 4621 4622 AVC_AUDIT_DATA_INIT(&ad, NET); 4623 ad.u.net.netif = ifindex; 4624 ad.u.net.family = family; 4625 if (selinux_parse_skb(skb, &ad, &addrp, 0, &proto)) 4626 return NF_DROP; 4627 4628 if (selinux_compat_net) { 4629 if (selinux_ip_postroute_iptables_compat(skb->sk, ifindex, 4630 &ad, family, addrp)) 4631 return NF_DROP; 4632 } else if (selinux_secmark_enabled()) { 4633 if (avc_has_perm(sksec->sid, skb->secmark, 4634 SECCLASS_PACKET, PACKET__SEND, &ad)) 4635 return NF_DROP; 4636 } 4637 4638 if (selinux_policycap_netpeer) 4639 if (selinux_xfrm_postroute_last(sksec->sid, skb, &ad, proto)) 4640 return NF_DROP; 4641 4642 return NF_ACCEPT; 4643 } 4644 4645 static unsigned int selinux_ip_postroute(struct sk_buff *skb, int ifindex, 4646 u16 family) 4647 { 4648 u32 secmark_perm; 4649 u32 peer_sid; 4650 struct sock *sk; 4651 struct avc_audit_data ad; 4652 char *addrp; 4653 u8 secmark_active; 4654 u8 peerlbl_active; 4655 4656 /* If any sort of compatibility mode is enabled then handoff processing 4657 * to the selinux_ip_postroute_compat() function to deal with the 4658 * special handling. We do this in an attempt to keep this function 4659 * as fast and as clean as possible. */ 4660 if (selinux_compat_net || !selinux_policycap_netpeer) 4661 return selinux_ip_postroute_compat(skb, ifindex, family); 4662 #ifdef CONFIG_XFRM 4663 /* If skb->dst->xfrm is non-NULL then the packet is undergoing an IPsec 4664 * packet transformation so allow the packet to pass without any checks 4665 * since we'll have another chance to perform access control checks 4666 * when the packet is on it's final way out. 4667 * NOTE: there appear to be some IPv6 multicast cases where skb->dst 4668 * is NULL, in this case go ahead and apply access control. */ 4669 if (skb->dst != NULL && skb->dst->xfrm != NULL) 4670 return NF_ACCEPT; 4671 #endif 4672 secmark_active = selinux_secmark_enabled(); 4673 peerlbl_active = netlbl_enabled() || selinux_xfrm_enabled(); 4674 if (!secmark_active && !peerlbl_active) 4675 return NF_ACCEPT; 4676 4677 /* if the packet is being forwarded then get the peer label from the 4678 * packet itself; otherwise check to see if it is from a local 4679 * application or the kernel, if from an application get the peer label 4680 * from the sending socket, otherwise use the kernel's sid */ 4681 sk = skb->sk; 4682 if (sk == NULL) { 4683 switch (family) { 4684 case PF_INET: 4685 if (IPCB(skb)->flags & IPSKB_FORWARDED) 4686 secmark_perm = PACKET__FORWARD_OUT; 4687 else 4688 secmark_perm = PACKET__SEND; 4689 break; 4690 case PF_INET6: 4691 if (IP6CB(skb)->flags & IP6SKB_FORWARDED) 4692 secmark_perm = PACKET__FORWARD_OUT; 4693 else 4694 secmark_perm = PACKET__SEND; 4695 break; 4696 default: 4697 return NF_DROP; 4698 } 4699 if (secmark_perm == PACKET__FORWARD_OUT) { 4700 if (selinux_skb_peerlbl_sid(skb, family, &peer_sid)) 4701 return NF_DROP; 4702 } else 4703 peer_sid = SECINITSID_KERNEL; 4704 } else { 4705 struct sk_security_struct *sksec = sk->sk_security; 4706 peer_sid = sksec->sid; 4707 secmark_perm = PACKET__SEND; 4708 } 4709 4710 AVC_AUDIT_DATA_INIT(&ad, NET); 4711 ad.u.net.netif = ifindex; 4712 ad.u.net.family = family; 4713 if (selinux_parse_skb(skb, &ad, &addrp, 0, NULL)) 4714 return NF_DROP; 4715 4716 if (secmark_active) 4717 if (avc_has_perm(peer_sid, skb->secmark, 4718 SECCLASS_PACKET, secmark_perm, &ad)) 4719 return NF_DROP; 4720 4721 if (peerlbl_active) { 4722 u32 if_sid; 4723 u32 node_sid; 4724 4725 if (sel_netif_sid(ifindex, &if_sid)) 4726 return NF_DROP; 4727 if (avc_has_perm(peer_sid, if_sid, 4728 SECCLASS_NETIF, NETIF__EGRESS, &ad)) 4729 return NF_DROP; 4730 4731 if (sel_netnode_sid(addrp, family, &node_sid)) 4732 return NF_DROP; 4733 if (avc_has_perm(peer_sid, node_sid, 4734 SECCLASS_NODE, NODE__SENDTO, &ad)) 4735 return NF_DROP; 4736 } 4737 4738 return NF_ACCEPT; 4739 } 4740 4741 static unsigned int selinux_ipv4_postroute(unsigned int hooknum, 4742 struct sk_buff *skb, 4743 const struct net_device *in, 4744 const struct net_device *out, 4745 int (*okfn)(struct sk_buff *)) 4746 { 4747 return selinux_ip_postroute(skb, out->ifindex, PF_INET); 4748 } 4749 4750 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE) 4751 static unsigned int selinux_ipv6_postroute(unsigned int hooknum, 4752 struct sk_buff *skb, 4753 const struct net_device *in, 4754 const struct net_device *out, 4755 int (*okfn)(struct sk_buff *)) 4756 { 4757 return selinux_ip_postroute(skb, out->ifindex, PF_INET6); 4758 } 4759 #endif /* IPV6 */ 4760 4761 #endif /* CONFIG_NETFILTER */ 4762 4763 static int selinux_netlink_send(struct sock *sk, struct sk_buff *skb) 4764 { 4765 int err; 4766 4767 err = cap_netlink_send(sk, skb); 4768 if (err) 4769 return err; 4770 4771 if (policydb_loaded_version >= POLICYDB_VERSION_NLCLASS) 4772 err = selinux_nlmsg_perm(sk, skb); 4773 4774 return err; 4775 } 4776 4777 static int selinux_netlink_recv(struct sk_buff *skb, int capability) 4778 { 4779 int err; 4780 struct avc_audit_data ad; 4781 4782 err = cap_netlink_recv(skb, capability); 4783 if (err) 4784 return err; 4785 4786 AVC_AUDIT_DATA_INIT(&ad, CAP); 4787 ad.u.cap = capability; 4788 4789 return avc_has_perm(NETLINK_CB(skb).sid, NETLINK_CB(skb).sid, 4790 SECCLASS_CAPABILITY, CAP_TO_MASK(capability), &ad); 4791 } 4792 4793 static int ipc_alloc_security(struct task_struct *task, 4794 struct kern_ipc_perm *perm, 4795 u16 sclass) 4796 { 4797 struct ipc_security_struct *isec; 4798 u32 sid; 4799 4800 isec = kzalloc(sizeof(struct ipc_security_struct), GFP_KERNEL); 4801 if (!isec) 4802 return -ENOMEM; 4803 4804 sid = task_sid(task); 4805 isec->sclass = sclass; 4806 isec->sid = sid; 4807 perm->security = isec; 4808 4809 return 0; 4810 } 4811 4812 static void ipc_free_security(struct kern_ipc_perm *perm) 4813 { 4814 struct ipc_security_struct *isec = perm->security; 4815 perm->security = NULL; 4816 kfree(isec); 4817 } 4818 4819 static int msg_msg_alloc_security(struct msg_msg *msg) 4820 { 4821 struct msg_security_struct *msec; 4822 4823 msec = kzalloc(sizeof(struct msg_security_struct), GFP_KERNEL); 4824 if (!msec) 4825 return -ENOMEM; 4826 4827 msec->sid = SECINITSID_UNLABELED; 4828 msg->security = msec; 4829 4830 return 0; 4831 } 4832 4833 static void msg_msg_free_security(struct msg_msg *msg) 4834 { 4835 struct msg_security_struct *msec = msg->security; 4836 4837 msg->security = NULL; 4838 kfree(msec); 4839 } 4840 4841 static int ipc_has_perm(struct kern_ipc_perm *ipc_perms, 4842 u32 perms) 4843 { 4844 struct ipc_security_struct *isec; 4845 struct avc_audit_data ad; 4846 u32 sid = current_sid(); 4847 4848 isec = ipc_perms->security; 4849 4850 AVC_AUDIT_DATA_INIT(&ad, IPC); 4851 ad.u.ipc_id = ipc_perms->key; 4852 4853 return avc_has_perm(sid, isec->sid, isec->sclass, perms, &ad); 4854 } 4855 4856 static int selinux_msg_msg_alloc_security(struct msg_msg *msg) 4857 { 4858 return msg_msg_alloc_security(msg); 4859 } 4860 4861 static void selinux_msg_msg_free_security(struct msg_msg *msg) 4862 { 4863 msg_msg_free_security(msg); 4864 } 4865 4866 /* message queue security operations */ 4867 static int selinux_msg_queue_alloc_security(struct msg_queue *msq) 4868 { 4869 struct ipc_security_struct *isec; 4870 struct avc_audit_data ad; 4871 u32 sid = current_sid(); 4872 int rc; 4873 4874 rc = ipc_alloc_security(current, &msq->q_perm, SECCLASS_MSGQ); 4875 if (rc) 4876 return rc; 4877 4878 isec = msq->q_perm.security; 4879 4880 AVC_AUDIT_DATA_INIT(&ad, IPC); 4881 ad.u.ipc_id = msq->q_perm.key; 4882 4883 rc = avc_has_perm(sid, isec->sid, SECCLASS_MSGQ, 4884 MSGQ__CREATE, &ad); 4885 if (rc) { 4886 ipc_free_security(&msq->q_perm); 4887 return rc; 4888 } 4889 return 0; 4890 } 4891 4892 static void selinux_msg_queue_free_security(struct msg_queue *msq) 4893 { 4894 ipc_free_security(&msq->q_perm); 4895 } 4896 4897 static int selinux_msg_queue_associate(struct msg_queue *msq, int msqflg) 4898 { 4899 struct ipc_security_struct *isec; 4900 struct avc_audit_data ad; 4901 u32 sid = current_sid(); 4902 4903 isec = msq->q_perm.security; 4904 4905 AVC_AUDIT_DATA_INIT(&ad, IPC); 4906 ad.u.ipc_id = msq->q_perm.key; 4907 4908 return avc_has_perm(sid, isec->sid, SECCLASS_MSGQ, 4909 MSGQ__ASSOCIATE, &ad); 4910 } 4911 4912 static int selinux_msg_queue_msgctl(struct msg_queue *msq, int cmd) 4913 { 4914 int err; 4915 int perms; 4916 4917 switch (cmd) { 4918 case IPC_INFO: 4919 case MSG_INFO: 4920 /* No specific object, just general system-wide information. */ 4921 return task_has_system(current, SYSTEM__IPC_INFO); 4922 case IPC_STAT: 4923 case MSG_STAT: 4924 perms = MSGQ__GETATTR | MSGQ__ASSOCIATE; 4925 break; 4926 case IPC_SET: 4927 perms = MSGQ__SETATTR; 4928 break; 4929 case IPC_RMID: 4930 perms = MSGQ__DESTROY; 4931 break; 4932 default: 4933 return 0; 4934 } 4935 4936 err = ipc_has_perm(&msq->q_perm, perms); 4937 return err; 4938 } 4939 4940 static int selinux_msg_queue_msgsnd(struct msg_queue *msq, struct msg_msg *msg, int msqflg) 4941 { 4942 struct ipc_security_struct *isec; 4943 struct msg_security_struct *msec; 4944 struct avc_audit_data ad; 4945 u32 sid = current_sid(); 4946 int rc; 4947 4948 isec = msq->q_perm.security; 4949 msec = msg->security; 4950 4951 /* 4952 * First time through, need to assign label to the message 4953 */ 4954 if (msec->sid == SECINITSID_UNLABELED) { 4955 /* 4956 * Compute new sid based on current process and 4957 * message queue this message will be stored in 4958 */ 4959 rc = security_transition_sid(sid, isec->sid, SECCLASS_MSG, 4960 &msec->sid); 4961 if (rc) 4962 return rc; 4963 } 4964 4965 AVC_AUDIT_DATA_INIT(&ad, IPC); 4966 ad.u.ipc_id = msq->q_perm.key; 4967 4968 /* Can this process write to the queue? */ 4969 rc = avc_has_perm(sid, isec->sid, SECCLASS_MSGQ, 4970 MSGQ__WRITE, &ad); 4971 if (!rc) 4972 /* Can this process send the message */ 4973 rc = avc_has_perm(sid, msec->sid, SECCLASS_MSG, 4974 MSG__SEND, &ad); 4975 if (!rc) 4976 /* Can the message be put in the queue? */ 4977 rc = avc_has_perm(msec->sid, isec->sid, SECCLASS_MSGQ, 4978 MSGQ__ENQUEUE, &ad); 4979 4980 return rc; 4981 } 4982 4983 static int selinux_msg_queue_msgrcv(struct msg_queue *msq, struct msg_msg *msg, 4984 struct task_struct *target, 4985 long type, int mode) 4986 { 4987 struct ipc_security_struct *isec; 4988 struct msg_security_struct *msec; 4989 struct avc_audit_data ad; 4990 u32 sid = task_sid(target); 4991 int rc; 4992 4993 isec = msq->q_perm.security; 4994 msec = msg->security; 4995 4996 AVC_AUDIT_DATA_INIT(&ad, IPC); 4997 ad.u.ipc_id = msq->q_perm.key; 4998 4999 rc = avc_has_perm(sid, isec->sid, 5000 SECCLASS_MSGQ, MSGQ__READ, &ad); 5001 if (!rc) 5002 rc = avc_has_perm(sid, msec->sid, 5003 SECCLASS_MSG, MSG__RECEIVE, &ad); 5004 return rc; 5005 } 5006 5007 /* Shared Memory security operations */ 5008 static int selinux_shm_alloc_security(struct shmid_kernel *shp) 5009 { 5010 struct ipc_security_struct *isec; 5011 struct avc_audit_data ad; 5012 u32 sid = current_sid(); 5013 int rc; 5014 5015 rc = ipc_alloc_security(current, &shp->shm_perm, SECCLASS_SHM); 5016 if (rc) 5017 return rc; 5018 5019 isec = shp->shm_perm.security; 5020 5021 AVC_AUDIT_DATA_INIT(&ad, IPC); 5022 ad.u.ipc_id = shp->shm_perm.key; 5023 5024 rc = avc_has_perm(sid, isec->sid, SECCLASS_SHM, 5025 SHM__CREATE, &ad); 5026 if (rc) { 5027 ipc_free_security(&shp->shm_perm); 5028 return rc; 5029 } 5030 return 0; 5031 } 5032 5033 static void selinux_shm_free_security(struct shmid_kernel *shp) 5034 { 5035 ipc_free_security(&shp->shm_perm); 5036 } 5037 5038 static int selinux_shm_associate(struct shmid_kernel *shp, int shmflg) 5039 { 5040 struct ipc_security_struct *isec; 5041 struct avc_audit_data ad; 5042 u32 sid = current_sid(); 5043 5044 isec = shp->shm_perm.security; 5045 5046 AVC_AUDIT_DATA_INIT(&ad, IPC); 5047 ad.u.ipc_id = shp->shm_perm.key; 5048 5049 return avc_has_perm(sid, isec->sid, SECCLASS_SHM, 5050 SHM__ASSOCIATE, &ad); 5051 } 5052 5053 /* Note, at this point, shp is locked down */ 5054 static int selinux_shm_shmctl(struct shmid_kernel *shp, int cmd) 5055 { 5056 int perms; 5057 int err; 5058 5059 switch (cmd) { 5060 case IPC_INFO: 5061 case SHM_INFO: 5062 /* No specific object, just general system-wide information. */ 5063 return task_has_system(current, SYSTEM__IPC_INFO); 5064 case IPC_STAT: 5065 case SHM_STAT: 5066 perms = SHM__GETATTR | SHM__ASSOCIATE; 5067 break; 5068 case IPC_SET: 5069 perms = SHM__SETATTR; 5070 break; 5071 case SHM_LOCK: 5072 case SHM_UNLOCK: 5073 perms = SHM__LOCK; 5074 break; 5075 case IPC_RMID: 5076 perms = SHM__DESTROY; 5077 break; 5078 default: 5079 return 0; 5080 } 5081 5082 err = ipc_has_perm(&shp->shm_perm, perms); 5083 return err; 5084 } 5085 5086 static int selinux_shm_shmat(struct shmid_kernel *shp, 5087 char __user *shmaddr, int shmflg) 5088 { 5089 u32 perms; 5090 5091 if (shmflg & SHM_RDONLY) 5092 perms = SHM__READ; 5093 else 5094 perms = SHM__READ | SHM__WRITE; 5095 5096 return ipc_has_perm(&shp->shm_perm, perms); 5097 } 5098 5099 /* Semaphore security operations */ 5100 static int selinux_sem_alloc_security(struct sem_array *sma) 5101 { 5102 struct ipc_security_struct *isec; 5103 struct avc_audit_data ad; 5104 u32 sid = current_sid(); 5105 int rc; 5106 5107 rc = ipc_alloc_security(current, &sma->sem_perm, SECCLASS_SEM); 5108 if (rc) 5109 return rc; 5110 5111 isec = sma->sem_perm.security; 5112 5113 AVC_AUDIT_DATA_INIT(&ad, IPC); 5114 ad.u.ipc_id = sma->sem_perm.key; 5115 5116 rc = avc_has_perm(sid, isec->sid, SECCLASS_SEM, 5117 SEM__CREATE, &ad); 5118 if (rc) { 5119 ipc_free_security(&sma->sem_perm); 5120 return rc; 5121 } 5122 return 0; 5123 } 5124 5125 static void selinux_sem_free_security(struct sem_array *sma) 5126 { 5127 ipc_free_security(&sma->sem_perm); 5128 } 5129 5130 static int selinux_sem_associate(struct sem_array *sma, int semflg) 5131 { 5132 struct ipc_security_struct *isec; 5133 struct avc_audit_data ad; 5134 u32 sid = current_sid(); 5135 5136 isec = sma->sem_perm.security; 5137 5138 AVC_AUDIT_DATA_INIT(&ad, IPC); 5139 ad.u.ipc_id = sma->sem_perm.key; 5140 5141 return avc_has_perm(sid, isec->sid, SECCLASS_SEM, 5142 SEM__ASSOCIATE, &ad); 5143 } 5144 5145 /* Note, at this point, sma is locked down */ 5146 static int selinux_sem_semctl(struct sem_array *sma, int cmd) 5147 { 5148 int err; 5149 u32 perms; 5150 5151 switch (cmd) { 5152 case IPC_INFO: 5153 case SEM_INFO: 5154 /* No specific object, just general system-wide information. */ 5155 return task_has_system(current, SYSTEM__IPC_INFO); 5156 case GETPID: 5157 case GETNCNT: 5158 case GETZCNT: 5159 perms = SEM__GETATTR; 5160 break; 5161 case GETVAL: 5162 case GETALL: 5163 perms = SEM__READ; 5164 break; 5165 case SETVAL: 5166 case SETALL: 5167 perms = SEM__WRITE; 5168 break; 5169 case IPC_RMID: 5170 perms = SEM__DESTROY; 5171 break; 5172 case IPC_SET: 5173 perms = SEM__SETATTR; 5174 break; 5175 case IPC_STAT: 5176 case SEM_STAT: 5177 perms = SEM__GETATTR | SEM__ASSOCIATE; 5178 break; 5179 default: 5180 return 0; 5181 } 5182 5183 err = ipc_has_perm(&sma->sem_perm, perms); 5184 return err; 5185 } 5186 5187 static int selinux_sem_semop(struct sem_array *sma, 5188 struct sembuf *sops, unsigned nsops, int alter) 5189 { 5190 u32 perms; 5191 5192 if (alter) 5193 perms = SEM__READ | SEM__WRITE; 5194 else 5195 perms = SEM__READ; 5196 5197 return ipc_has_perm(&sma->sem_perm, perms); 5198 } 5199 5200 static int selinux_ipc_permission(struct kern_ipc_perm *ipcp, short flag) 5201 { 5202 u32 av = 0; 5203 5204 av = 0; 5205 if (flag & S_IRUGO) 5206 av |= IPC__UNIX_READ; 5207 if (flag & S_IWUGO) 5208 av |= IPC__UNIX_WRITE; 5209 5210 if (av == 0) 5211 return 0; 5212 5213 return ipc_has_perm(ipcp, av); 5214 } 5215 5216 static void selinux_ipc_getsecid(struct kern_ipc_perm *ipcp, u32 *secid) 5217 { 5218 struct ipc_security_struct *isec = ipcp->security; 5219 *secid = isec->sid; 5220 } 5221 5222 static void selinux_d_instantiate(struct dentry *dentry, struct inode *inode) 5223 { 5224 if (inode) 5225 inode_doinit_with_dentry(inode, dentry); 5226 } 5227 5228 static int selinux_getprocattr(struct task_struct *p, 5229 char *name, char **value) 5230 { 5231 const struct task_security_struct *__tsec; 5232 u32 sid; 5233 int error; 5234 unsigned len; 5235 5236 if (current != p) { 5237 error = current_has_perm(p, PROCESS__GETATTR); 5238 if (error) 5239 return error; 5240 } 5241 5242 rcu_read_lock(); 5243 __tsec = __task_cred(p)->security; 5244 5245 if (!strcmp(name, "current")) 5246 sid = __tsec->sid; 5247 else if (!strcmp(name, "prev")) 5248 sid = __tsec->osid; 5249 else if (!strcmp(name, "exec")) 5250 sid = __tsec->exec_sid; 5251 else if (!strcmp(name, "fscreate")) 5252 sid = __tsec->create_sid; 5253 else if (!strcmp(name, "keycreate")) 5254 sid = __tsec->keycreate_sid; 5255 else if (!strcmp(name, "sockcreate")) 5256 sid = __tsec->sockcreate_sid; 5257 else 5258 goto invalid; 5259 rcu_read_unlock(); 5260 5261 if (!sid) 5262 return 0; 5263 5264 error = security_sid_to_context(sid, value, &len); 5265 if (error) 5266 return error; 5267 return len; 5268 5269 invalid: 5270 rcu_read_unlock(); 5271 return -EINVAL; 5272 } 5273 5274 static int selinux_setprocattr(struct task_struct *p, 5275 char *name, void *value, size_t size) 5276 { 5277 struct task_security_struct *tsec; 5278 struct task_struct *tracer; 5279 struct cred *new; 5280 u32 sid = 0, ptsid; 5281 int error; 5282 char *str = value; 5283 5284 if (current != p) { 5285 /* SELinux only allows a process to change its own 5286 security attributes. */ 5287 return -EACCES; 5288 } 5289 5290 /* 5291 * Basic control over ability to set these attributes at all. 5292 * current == p, but we'll pass them separately in case the 5293 * above restriction is ever removed. 5294 */ 5295 if (!strcmp(name, "exec")) 5296 error = current_has_perm(p, PROCESS__SETEXEC); 5297 else if (!strcmp(name, "fscreate")) 5298 error = current_has_perm(p, PROCESS__SETFSCREATE); 5299 else if (!strcmp(name, "keycreate")) 5300 error = current_has_perm(p, PROCESS__SETKEYCREATE); 5301 else if (!strcmp(name, "sockcreate")) 5302 error = current_has_perm(p, PROCESS__SETSOCKCREATE); 5303 else if (!strcmp(name, "current")) 5304 error = current_has_perm(p, PROCESS__SETCURRENT); 5305 else 5306 error = -EINVAL; 5307 if (error) 5308 return error; 5309 5310 /* Obtain a SID for the context, if one was specified. */ 5311 if (size && str[1] && str[1] != '\n') { 5312 if (str[size-1] == '\n') { 5313 str[size-1] = 0; 5314 size--; 5315 } 5316 error = security_context_to_sid(value, size, &sid); 5317 if (error == -EINVAL && !strcmp(name, "fscreate")) { 5318 if (!capable(CAP_MAC_ADMIN)) 5319 return error; 5320 error = security_context_to_sid_force(value, size, 5321 &sid); 5322 } 5323 if (error) 5324 return error; 5325 } 5326 5327 new = prepare_creds(); 5328 if (!new) 5329 return -ENOMEM; 5330 5331 /* Permission checking based on the specified context is 5332 performed during the actual operation (execve, 5333 open/mkdir/...), when we know the full context of the 5334 operation. See selinux_bprm_set_creds for the execve 5335 checks and may_create for the file creation checks. The 5336 operation will then fail if the context is not permitted. */ 5337 tsec = new->security; 5338 if (!strcmp(name, "exec")) { 5339 tsec->exec_sid = sid; 5340 } else if (!strcmp(name, "fscreate")) { 5341 tsec->create_sid = sid; 5342 } else if (!strcmp(name, "keycreate")) { 5343 error = may_create_key(sid, p); 5344 if (error) 5345 goto abort_change; 5346 tsec->keycreate_sid = sid; 5347 } else if (!strcmp(name, "sockcreate")) { 5348 tsec->sockcreate_sid = sid; 5349 } else if (!strcmp(name, "current")) { 5350 error = -EINVAL; 5351 if (sid == 0) 5352 goto abort_change; 5353 5354 /* Only allow single threaded processes to change context */ 5355 error = -EPERM; 5356 if (!is_single_threaded(p)) { 5357 error = security_bounded_transition(tsec->sid, sid); 5358 if (error) 5359 goto abort_change; 5360 } 5361 5362 /* Check permissions for the transition. */ 5363 error = avc_has_perm(tsec->sid, sid, SECCLASS_PROCESS, 5364 PROCESS__DYNTRANSITION, NULL); 5365 if (error) 5366 goto abort_change; 5367 5368 /* Check for ptracing, and update the task SID if ok. 5369 Otherwise, leave SID unchanged and fail. */ 5370 ptsid = 0; 5371 task_lock(p); 5372 tracer = tracehook_tracer_task(p); 5373 if (tracer) 5374 ptsid = task_sid(tracer); 5375 task_unlock(p); 5376 5377 if (tracer) { 5378 error = avc_has_perm(ptsid, sid, SECCLASS_PROCESS, 5379 PROCESS__PTRACE, NULL); 5380 if (error) 5381 goto abort_change; 5382 } 5383 5384 tsec->sid = sid; 5385 } else { 5386 error = -EINVAL; 5387 goto abort_change; 5388 } 5389 5390 commit_creds(new); 5391 return size; 5392 5393 abort_change: 5394 abort_creds(new); 5395 return error; 5396 } 5397 5398 static int selinux_secid_to_secctx(u32 secid, char **secdata, u32 *seclen) 5399 { 5400 return security_sid_to_context(secid, secdata, seclen); 5401 } 5402 5403 static int selinux_secctx_to_secid(const char *secdata, u32 seclen, u32 *secid) 5404 { 5405 return security_context_to_sid(secdata, seclen, secid); 5406 } 5407 5408 static void selinux_release_secctx(char *secdata, u32 seclen) 5409 { 5410 kfree(secdata); 5411 } 5412 5413 #ifdef CONFIG_KEYS 5414 5415 static int selinux_key_alloc(struct key *k, const struct cred *cred, 5416 unsigned long flags) 5417 { 5418 const struct task_security_struct *tsec; 5419 struct key_security_struct *ksec; 5420 5421 ksec = kzalloc(sizeof(struct key_security_struct), GFP_KERNEL); 5422 if (!ksec) 5423 return -ENOMEM; 5424 5425 tsec = cred->security; 5426 if (tsec->keycreate_sid) 5427 ksec->sid = tsec->keycreate_sid; 5428 else 5429 ksec->sid = tsec->sid; 5430 5431 k->security = ksec; 5432 return 0; 5433 } 5434 5435 static void selinux_key_free(struct key *k) 5436 { 5437 struct key_security_struct *ksec = k->security; 5438 5439 k->security = NULL; 5440 kfree(ksec); 5441 } 5442 5443 static int selinux_key_permission(key_ref_t key_ref, 5444 const struct cred *cred, 5445 key_perm_t perm) 5446 { 5447 struct key *key; 5448 struct key_security_struct *ksec; 5449 u32 sid; 5450 5451 /* if no specific permissions are requested, we skip the 5452 permission check. No serious, additional covert channels 5453 appear to be created. */ 5454 if (perm == 0) 5455 return 0; 5456 5457 sid = cred_sid(cred); 5458 5459 key = key_ref_to_ptr(key_ref); 5460 ksec = key->security; 5461 5462 return avc_has_perm(sid, ksec->sid, SECCLASS_KEY, perm, NULL); 5463 } 5464 5465 static int selinux_key_getsecurity(struct key *key, char **_buffer) 5466 { 5467 struct key_security_struct *ksec = key->security; 5468 char *context = NULL; 5469 unsigned len; 5470 int rc; 5471 5472 rc = security_sid_to_context(ksec->sid, &context, &len); 5473 if (!rc) 5474 rc = len; 5475 *_buffer = context; 5476 return rc; 5477 } 5478 5479 #endif 5480 5481 static struct security_operations selinux_ops = { 5482 .name = "selinux", 5483 5484 .ptrace_may_access = selinux_ptrace_may_access, 5485 .ptrace_traceme = selinux_ptrace_traceme, 5486 .capget = selinux_capget, 5487 .capset = selinux_capset, 5488 .sysctl = selinux_sysctl, 5489 .capable = selinux_capable, 5490 .quotactl = selinux_quotactl, 5491 .quota_on = selinux_quota_on, 5492 .syslog = selinux_syslog, 5493 .vm_enough_memory = selinux_vm_enough_memory, 5494 5495 .netlink_send = selinux_netlink_send, 5496 .netlink_recv = selinux_netlink_recv, 5497 5498 .bprm_set_creds = selinux_bprm_set_creds, 5499 .bprm_committing_creds = selinux_bprm_committing_creds, 5500 .bprm_committed_creds = selinux_bprm_committed_creds, 5501 .bprm_secureexec = selinux_bprm_secureexec, 5502 5503 .sb_alloc_security = selinux_sb_alloc_security, 5504 .sb_free_security = selinux_sb_free_security, 5505 .sb_copy_data = selinux_sb_copy_data, 5506 .sb_kern_mount = selinux_sb_kern_mount, 5507 .sb_show_options = selinux_sb_show_options, 5508 .sb_statfs = selinux_sb_statfs, 5509 .sb_mount = selinux_mount, 5510 .sb_umount = selinux_umount, 5511 .sb_set_mnt_opts = selinux_set_mnt_opts, 5512 .sb_clone_mnt_opts = selinux_sb_clone_mnt_opts, 5513 .sb_parse_opts_str = selinux_parse_opts_str, 5514 5515 5516 .inode_alloc_security = selinux_inode_alloc_security, 5517 .inode_free_security = selinux_inode_free_security, 5518 .inode_init_security = selinux_inode_init_security, 5519 .inode_create = selinux_inode_create, 5520 .inode_link = selinux_inode_link, 5521 .inode_unlink = selinux_inode_unlink, 5522 .inode_symlink = selinux_inode_symlink, 5523 .inode_mkdir = selinux_inode_mkdir, 5524 .inode_rmdir = selinux_inode_rmdir, 5525 .inode_mknod = selinux_inode_mknod, 5526 .inode_rename = selinux_inode_rename, 5527 .inode_readlink = selinux_inode_readlink, 5528 .inode_follow_link = selinux_inode_follow_link, 5529 .inode_permission = selinux_inode_permission, 5530 .inode_setattr = selinux_inode_setattr, 5531 .inode_getattr = selinux_inode_getattr, 5532 .inode_setxattr = selinux_inode_setxattr, 5533 .inode_post_setxattr = selinux_inode_post_setxattr, 5534 .inode_getxattr = selinux_inode_getxattr, 5535 .inode_listxattr = selinux_inode_listxattr, 5536 .inode_removexattr = selinux_inode_removexattr, 5537 .inode_getsecurity = selinux_inode_getsecurity, 5538 .inode_setsecurity = selinux_inode_setsecurity, 5539 .inode_listsecurity = selinux_inode_listsecurity, 5540 .inode_getsecid = selinux_inode_getsecid, 5541 5542 .file_permission = selinux_file_permission, 5543 .file_alloc_security = selinux_file_alloc_security, 5544 .file_free_security = selinux_file_free_security, 5545 .file_ioctl = selinux_file_ioctl, 5546 .file_mmap = selinux_file_mmap, 5547 .file_mprotect = selinux_file_mprotect, 5548 .file_lock = selinux_file_lock, 5549 .file_fcntl = selinux_file_fcntl, 5550 .file_set_fowner = selinux_file_set_fowner, 5551 .file_send_sigiotask = selinux_file_send_sigiotask, 5552 .file_receive = selinux_file_receive, 5553 5554 .dentry_open = selinux_dentry_open, 5555 5556 .task_create = selinux_task_create, 5557 .cred_free = selinux_cred_free, 5558 .cred_prepare = selinux_cred_prepare, 5559 .kernel_act_as = selinux_kernel_act_as, 5560 .kernel_create_files_as = selinux_kernel_create_files_as, 5561 .task_setpgid = selinux_task_setpgid, 5562 .task_getpgid = selinux_task_getpgid, 5563 .task_getsid = selinux_task_getsid, 5564 .task_getsecid = selinux_task_getsecid, 5565 .task_setnice = selinux_task_setnice, 5566 .task_setioprio = selinux_task_setioprio, 5567 .task_getioprio = selinux_task_getioprio, 5568 .task_setrlimit = selinux_task_setrlimit, 5569 .task_setscheduler = selinux_task_setscheduler, 5570 .task_getscheduler = selinux_task_getscheduler, 5571 .task_movememory = selinux_task_movememory, 5572 .task_kill = selinux_task_kill, 5573 .task_wait = selinux_task_wait, 5574 .task_to_inode = selinux_task_to_inode, 5575 5576 .ipc_permission = selinux_ipc_permission, 5577 .ipc_getsecid = selinux_ipc_getsecid, 5578 5579 .msg_msg_alloc_security = selinux_msg_msg_alloc_security, 5580 .msg_msg_free_security = selinux_msg_msg_free_security, 5581 5582 .msg_queue_alloc_security = selinux_msg_queue_alloc_security, 5583 .msg_queue_free_security = selinux_msg_queue_free_security, 5584 .msg_queue_associate = selinux_msg_queue_associate, 5585 .msg_queue_msgctl = selinux_msg_queue_msgctl, 5586 .msg_queue_msgsnd = selinux_msg_queue_msgsnd, 5587 .msg_queue_msgrcv = selinux_msg_queue_msgrcv, 5588 5589 .shm_alloc_security = selinux_shm_alloc_security, 5590 .shm_free_security = selinux_shm_free_security, 5591 .shm_associate = selinux_shm_associate, 5592 .shm_shmctl = selinux_shm_shmctl, 5593 .shm_shmat = selinux_shm_shmat, 5594 5595 .sem_alloc_security = selinux_sem_alloc_security, 5596 .sem_free_security = selinux_sem_free_security, 5597 .sem_associate = selinux_sem_associate, 5598 .sem_semctl = selinux_sem_semctl, 5599 .sem_semop = selinux_sem_semop, 5600 5601 .d_instantiate = selinux_d_instantiate, 5602 5603 .getprocattr = selinux_getprocattr, 5604 .setprocattr = selinux_setprocattr, 5605 5606 .secid_to_secctx = selinux_secid_to_secctx, 5607 .secctx_to_secid = selinux_secctx_to_secid, 5608 .release_secctx = selinux_release_secctx, 5609 5610 .unix_stream_connect = selinux_socket_unix_stream_connect, 5611 .unix_may_send = selinux_socket_unix_may_send, 5612 5613 .socket_create = selinux_socket_create, 5614 .socket_post_create = selinux_socket_post_create, 5615 .socket_bind = selinux_socket_bind, 5616 .socket_connect = selinux_socket_connect, 5617 .socket_listen = selinux_socket_listen, 5618 .socket_accept = selinux_socket_accept, 5619 .socket_sendmsg = selinux_socket_sendmsg, 5620 .socket_recvmsg = selinux_socket_recvmsg, 5621 .socket_getsockname = selinux_socket_getsockname, 5622 .socket_getpeername = selinux_socket_getpeername, 5623 .socket_getsockopt = selinux_socket_getsockopt, 5624 .socket_setsockopt = selinux_socket_setsockopt, 5625 .socket_shutdown = selinux_socket_shutdown, 5626 .socket_sock_rcv_skb = selinux_socket_sock_rcv_skb, 5627 .socket_getpeersec_stream = selinux_socket_getpeersec_stream, 5628 .socket_getpeersec_dgram = selinux_socket_getpeersec_dgram, 5629 .sk_alloc_security = selinux_sk_alloc_security, 5630 .sk_free_security = selinux_sk_free_security, 5631 .sk_clone_security = selinux_sk_clone_security, 5632 .sk_getsecid = selinux_sk_getsecid, 5633 .sock_graft = selinux_sock_graft, 5634 .inet_conn_request = selinux_inet_conn_request, 5635 .inet_csk_clone = selinux_inet_csk_clone, 5636 .inet_conn_established = selinux_inet_conn_established, 5637 .req_classify_flow = selinux_req_classify_flow, 5638 5639 #ifdef CONFIG_SECURITY_NETWORK_XFRM 5640 .xfrm_policy_alloc_security = selinux_xfrm_policy_alloc, 5641 .xfrm_policy_clone_security = selinux_xfrm_policy_clone, 5642 .xfrm_policy_free_security = selinux_xfrm_policy_free, 5643 .xfrm_policy_delete_security = selinux_xfrm_policy_delete, 5644 .xfrm_state_alloc_security = selinux_xfrm_state_alloc, 5645 .xfrm_state_free_security = selinux_xfrm_state_free, 5646 .xfrm_state_delete_security = selinux_xfrm_state_delete, 5647 .xfrm_policy_lookup = selinux_xfrm_policy_lookup, 5648 .xfrm_state_pol_flow_match = selinux_xfrm_state_pol_flow_match, 5649 .xfrm_decode_session = selinux_xfrm_decode_session, 5650 #endif 5651 5652 #ifdef CONFIG_KEYS 5653 .key_alloc = selinux_key_alloc, 5654 .key_free = selinux_key_free, 5655 .key_permission = selinux_key_permission, 5656 .key_getsecurity = selinux_key_getsecurity, 5657 #endif 5658 5659 #ifdef CONFIG_AUDIT 5660 .audit_rule_init = selinux_audit_rule_init, 5661 .audit_rule_known = selinux_audit_rule_known, 5662 .audit_rule_match = selinux_audit_rule_match, 5663 .audit_rule_free = selinux_audit_rule_free, 5664 #endif 5665 }; 5666 5667 static __init int selinux_init(void) 5668 { 5669 if (!security_module_enable(&selinux_ops)) { 5670 selinux_enabled = 0; 5671 return 0; 5672 } 5673 5674 if (!selinux_enabled) { 5675 printk(KERN_INFO "SELinux: Disabled at boot.\n"); 5676 return 0; 5677 } 5678 5679 printk(KERN_INFO "SELinux: Initializing.\n"); 5680 5681 /* Set the security state for the initial task. */ 5682 cred_init_security(); 5683 5684 sel_inode_cache = kmem_cache_create("selinux_inode_security", 5685 sizeof(struct inode_security_struct), 5686 0, SLAB_PANIC, NULL); 5687 avc_init(); 5688 5689 secondary_ops = security_ops; 5690 if (!secondary_ops) 5691 panic("SELinux: No initial security operations\n"); 5692 if (register_security(&selinux_ops)) 5693 panic("SELinux: Unable to register with kernel.\n"); 5694 5695 if (selinux_enforcing) 5696 printk(KERN_DEBUG "SELinux: Starting in enforcing mode\n"); 5697 else 5698 printk(KERN_DEBUG "SELinux: Starting in permissive mode\n"); 5699 5700 return 0; 5701 } 5702 5703 void selinux_complete_init(void) 5704 { 5705 printk(KERN_DEBUG "SELinux: Completing initialization.\n"); 5706 5707 /* Set up any superblocks initialized prior to the policy load. */ 5708 printk(KERN_DEBUG "SELinux: Setting up existing superblocks.\n"); 5709 spin_lock(&sb_lock); 5710 spin_lock(&sb_security_lock); 5711 next_sb: 5712 if (!list_empty(&superblock_security_head)) { 5713 struct superblock_security_struct *sbsec = 5714 list_entry(superblock_security_head.next, 5715 struct superblock_security_struct, 5716 list); 5717 struct super_block *sb = sbsec->sb; 5718 sb->s_count++; 5719 spin_unlock(&sb_security_lock); 5720 spin_unlock(&sb_lock); 5721 down_read(&sb->s_umount); 5722 if (sb->s_root) 5723 superblock_doinit(sb, NULL); 5724 drop_super(sb); 5725 spin_lock(&sb_lock); 5726 spin_lock(&sb_security_lock); 5727 list_del_init(&sbsec->list); 5728 goto next_sb; 5729 } 5730 spin_unlock(&sb_security_lock); 5731 spin_unlock(&sb_lock); 5732 } 5733 5734 /* SELinux requires early initialization in order to label 5735 all processes and objects when they are created. */ 5736 security_initcall(selinux_init); 5737 5738 #if defined(CONFIG_NETFILTER) 5739 5740 static struct nf_hook_ops selinux_ipv4_ops[] = { 5741 { 5742 .hook = selinux_ipv4_postroute, 5743 .owner = THIS_MODULE, 5744 .pf = PF_INET, 5745 .hooknum = NF_INET_POST_ROUTING, 5746 .priority = NF_IP_PRI_SELINUX_LAST, 5747 }, 5748 { 5749 .hook = selinux_ipv4_forward, 5750 .owner = THIS_MODULE, 5751 .pf = PF_INET, 5752 .hooknum = NF_INET_FORWARD, 5753 .priority = NF_IP_PRI_SELINUX_FIRST, 5754 }, 5755 { 5756 .hook = selinux_ipv4_output, 5757 .owner = THIS_MODULE, 5758 .pf = PF_INET, 5759 .hooknum = NF_INET_LOCAL_OUT, 5760 .priority = NF_IP_PRI_SELINUX_FIRST, 5761 } 5762 }; 5763 5764 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE) 5765 5766 static struct nf_hook_ops selinux_ipv6_ops[] = { 5767 { 5768 .hook = selinux_ipv6_postroute, 5769 .owner = THIS_MODULE, 5770 .pf = PF_INET6, 5771 .hooknum = NF_INET_POST_ROUTING, 5772 .priority = NF_IP6_PRI_SELINUX_LAST, 5773 }, 5774 { 5775 .hook = selinux_ipv6_forward, 5776 .owner = THIS_MODULE, 5777 .pf = PF_INET6, 5778 .hooknum = NF_INET_FORWARD, 5779 .priority = NF_IP6_PRI_SELINUX_FIRST, 5780 } 5781 }; 5782 5783 #endif /* IPV6 */ 5784 5785 static int __init selinux_nf_ip_init(void) 5786 { 5787 int err = 0; 5788 5789 if (!selinux_enabled) 5790 goto out; 5791 5792 printk(KERN_DEBUG "SELinux: Registering netfilter hooks\n"); 5793 5794 err = nf_register_hooks(selinux_ipv4_ops, ARRAY_SIZE(selinux_ipv4_ops)); 5795 if (err) 5796 panic("SELinux: nf_register_hooks for IPv4: error %d\n", err); 5797 5798 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE) 5799 err = nf_register_hooks(selinux_ipv6_ops, ARRAY_SIZE(selinux_ipv6_ops)); 5800 if (err) 5801 panic("SELinux: nf_register_hooks for IPv6: error %d\n", err); 5802 #endif /* IPV6 */ 5803 5804 out: 5805 return err; 5806 } 5807 5808 __initcall(selinux_nf_ip_init); 5809 5810 #ifdef CONFIG_SECURITY_SELINUX_DISABLE 5811 static void selinux_nf_ip_exit(void) 5812 { 5813 printk(KERN_DEBUG "SELinux: Unregistering netfilter hooks\n"); 5814 5815 nf_unregister_hooks(selinux_ipv4_ops, ARRAY_SIZE(selinux_ipv4_ops)); 5816 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE) 5817 nf_unregister_hooks(selinux_ipv6_ops, ARRAY_SIZE(selinux_ipv6_ops)); 5818 #endif /* IPV6 */ 5819 } 5820 #endif 5821 5822 #else /* CONFIG_NETFILTER */ 5823 5824 #ifdef CONFIG_SECURITY_SELINUX_DISABLE 5825 #define selinux_nf_ip_exit() 5826 #endif 5827 5828 #endif /* CONFIG_NETFILTER */ 5829 5830 #ifdef CONFIG_SECURITY_SELINUX_DISABLE 5831 static int selinux_disabled; 5832 5833 int selinux_disable(void) 5834 { 5835 extern void exit_sel_fs(void); 5836 5837 if (ss_initialized) { 5838 /* Not permitted after initial policy load. */ 5839 return -EINVAL; 5840 } 5841 5842 if (selinux_disabled) { 5843 /* Only do this once. */ 5844 return -EINVAL; 5845 } 5846 5847 printk(KERN_INFO "SELinux: Disabled at runtime.\n"); 5848 5849 selinux_disabled = 1; 5850 selinux_enabled = 0; 5851 5852 /* Reset security_ops to the secondary module, dummy or capability. */ 5853 security_ops = secondary_ops; 5854 5855 /* Unregister netfilter hooks. */ 5856 selinux_nf_ip_exit(); 5857 5858 /* Unregister selinuxfs. */ 5859 exit_sel_fs(); 5860 5861 return 0; 5862 } 5863 #endif 5864