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, 2009 Hewlett-Packard Development Company, L.P. 17 * Paul Moore <paul@paul-moore.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/kd.h> 28 #include <linux/kernel.h> 29 #include <linux/tracehook.h> 30 #include <linux/errno.h> 31 #include <linux/sched.h> 32 #include <linux/security.h> 33 #include <linux/xattr.h> 34 #include <linux/capability.h> 35 #include <linux/unistd.h> 36 #include <linux/mm.h> 37 #include <linux/mman.h> 38 #include <linux/slab.h> 39 #include <linux/pagemap.h> 40 #include <linux/proc_fs.h> 41 #include <linux/swap.h> 42 #include <linux/spinlock.h> 43 #include <linux/syscalls.h> 44 #include <linux/dcache.h> 45 #include <linux/file.h> 46 #include <linux/fdtable.h> 47 #include <linux/namei.h> 48 #include <linux/mount.h> 49 #include <linux/netfilter_ipv4.h> 50 #include <linux/netfilter_ipv6.h> 51 #include <linux/tty.h> 52 #include <net/icmp.h> 53 #include <net/ip.h> /* for local_port_range[] */ 54 #include <net/tcp.h> /* struct or_callable used in sock_rcv_skb */ 55 #include <net/net_namespace.h> 56 #include <net/netlabel.h> 57 #include <linux/uaccess.h> 58 #include <asm/ioctls.h> 59 #include <linux/atomic.h> 60 #include <linux/bitops.h> 61 #include <linux/interrupt.h> 62 #include <linux/netdevice.h> /* for network interface checks */ 63 #include <linux/netlink.h> 64 #include <linux/tcp.h> 65 #include <linux/udp.h> 66 #include <linux/dccp.h> 67 #include <linux/quota.h> 68 #include <linux/un.h> /* for Unix socket types */ 69 #include <net/af_unix.h> /* for Unix socket types */ 70 #include <linux/parser.h> 71 #include <linux/nfs_mount.h> 72 #include <net/ipv6.h> 73 #include <linux/hugetlb.h> 74 #include <linux/personality.h> 75 #include <linux/audit.h> 76 #include <linux/string.h> 77 #include <linux/selinux.h> 78 #include <linux/mutex.h> 79 #include <linux/posix-timers.h> 80 #include <linux/syslog.h> 81 #include <linux/user_namespace.h> 82 #include <linux/export.h> 83 #include <linux/msg.h> 84 #include <linux/shm.h> 85 86 #include "avc.h" 87 #include "objsec.h" 88 #include "netif.h" 89 #include "netnode.h" 90 #include "netport.h" 91 #include "xfrm.h" 92 #include "netlabel.h" 93 #include "audit.h" 94 #include "avc_ss.h" 95 96 #define NUM_SEL_MNT_OPTS 5 97 98 extern struct security_operations *security_ops; 99 100 /* SECMARK reference count */ 101 static atomic_t selinux_secmark_refcount = ATOMIC_INIT(0); 102 103 #ifdef CONFIG_SECURITY_SELINUX_DEVELOP 104 int selinux_enforcing; 105 106 static int __init enforcing_setup(char *str) 107 { 108 unsigned long enforcing; 109 if (!strict_strtoul(str, 0, &enforcing)) 110 selinux_enforcing = enforcing ? 1 : 0; 111 return 1; 112 } 113 __setup("enforcing=", enforcing_setup); 114 #endif 115 116 #ifdef CONFIG_SECURITY_SELINUX_BOOTPARAM 117 int selinux_enabled = CONFIG_SECURITY_SELINUX_BOOTPARAM_VALUE; 118 119 static int __init selinux_enabled_setup(char *str) 120 { 121 unsigned long enabled; 122 if (!strict_strtoul(str, 0, &enabled)) 123 selinux_enabled = enabled ? 1 : 0; 124 return 1; 125 } 126 __setup("selinux=", selinux_enabled_setup); 127 #else 128 int selinux_enabled = 1; 129 #endif 130 131 static struct kmem_cache *sel_inode_cache; 132 133 /** 134 * selinux_secmark_enabled - Check to see if SECMARK is currently enabled 135 * 136 * Description: 137 * This function checks the SECMARK reference counter to see if any SECMARK 138 * targets are currently configured, if the reference counter is greater than 139 * zero SECMARK is considered to be enabled. Returns true (1) if SECMARK is 140 * enabled, false (0) if SECMARK is disabled. 141 * 142 */ 143 static int selinux_secmark_enabled(void) 144 { 145 return (atomic_read(&selinux_secmark_refcount) > 0); 146 } 147 148 /* 149 * initialise the security for the init task 150 */ 151 static void cred_init_security(void) 152 { 153 struct cred *cred = (struct cred *) current->real_cred; 154 struct task_security_struct *tsec; 155 156 tsec = kzalloc(sizeof(struct task_security_struct), GFP_KERNEL); 157 if (!tsec) 158 panic("SELinux: Failed to initialize initial task.\n"); 159 160 tsec->osid = tsec->sid = SECINITSID_KERNEL; 161 cred->security = tsec; 162 } 163 164 /* 165 * get the security ID of a set of credentials 166 */ 167 static inline u32 cred_sid(const struct cred *cred) 168 { 169 const struct task_security_struct *tsec; 170 171 tsec = cred->security; 172 return tsec->sid; 173 } 174 175 /* 176 * get the objective security ID of a task 177 */ 178 static inline u32 task_sid(const struct task_struct *task) 179 { 180 u32 sid; 181 182 rcu_read_lock(); 183 sid = cred_sid(__task_cred(task)); 184 rcu_read_unlock(); 185 return sid; 186 } 187 188 /* 189 * get the subjective security ID of the current task 190 */ 191 static inline u32 current_sid(void) 192 { 193 const struct task_security_struct *tsec = current_security(); 194 195 return tsec->sid; 196 } 197 198 /* Allocate and free functions for each kind of security blob. */ 199 200 static int inode_alloc_security(struct inode *inode) 201 { 202 struct inode_security_struct *isec; 203 u32 sid = current_sid(); 204 205 isec = kmem_cache_zalloc(sel_inode_cache, GFP_NOFS); 206 if (!isec) 207 return -ENOMEM; 208 209 mutex_init(&isec->lock); 210 INIT_LIST_HEAD(&isec->list); 211 isec->inode = inode; 212 isec->sid = SECINITSID_UNLABELED; 213 isec->sclass = SECCLASS_FILE; 214 isec->task_sid = sid; 215 inode->i_security = isec; 216 217 return 0; 218 } 219 220 static void inode_free_security(struct inode *inode) 221 { 222 struct inode_security_struct *isec = inode->i_security; 223 struct superblock_security_struct *sbsec = inode->i_sb->s_security; 224 225 spin_lock(&sbsec->isec_lock); 226 if (!list_empty(&isec->list)) 227 list_del_init(&isec->list); 228 spin_unlock(&sbsec->isec_lock); 229 230 inode->i_security = NULL; 231 kmem_cache_free(sel_inode_cache, isec); 232 } 233 234 static int file_alloc_security(struct file *file) 235 { 236 struct file_security_struct *fsec; 237 u32 sid = current_sid(); 238 239 fsec = kzalloc(sizeof(struct file_security_struct), GFP_KERNEL); 240 if (!fsec) 241 return -ENOMEM; 242 243 fsec->sid = sid; 244 fsec->fown_sid = sid; 245 file->f_security = fsec; 246 247 return 0; 248 } 249 250 static void file_free_security(struct file *file) 251 { 252 struct file_security_struct *fsec = file->f_security; 253 file->f_security = NULL; 254 kfree(fsec); 255 } 256 257 static int superblock_alloc_security(struct super_block *sb) 258 { 259 struct superblock_security_struct *sbsec; 260 261 sbsec = kzalloc(sizeof(struct superblock_security_struct), GFP_KERNEL); 262 if (!sbsec) 263 return -ENOMEM; 264 265 mutex_init(&sbsec->lock); 266 INIT_LIST_HEAD(&sbsec->isec_head); 267 spin_lock_init(&sbsec->isec_lock); 268 sbsec->sb = sb; 269 sbsec->sid = SECINITSID_UNLABELED; 270 sbsec->def_sid = SECINITSID_FILE; 271 sbsec->mntpoint_sid = SECINITSID_UNLABELED; 272 sb->s_security = sbsec; 273 274 return 0; 275 } 276 277 static void superblock_free_security(struct super_block *sb) 278 { 279 struct superblock_security_struct *sbsec = sb->s_security; 280 sb->s_security = NULL; 281 kfree(sbsec); 282 } 283 284 /* The file system's label must be initialized prior to use. */ 285 286 static const char *labeling_behaviors[6] = { 287 "uses xattr", 288 "uses transition SIDs", 289 "uses task SIDs", 290 "uses genfs_contexts", 291 "not configured for labeling", 292 "uses mountpoint labeling", 293 }; 294 295 static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dentry); 296 297 static inline int inode_doinit(struct inode *inode) 298 { 299 return inode_doinit_with_dentry(inode, NULL); 300 } 301 302 enum { 303 Opt_error = -1, 304 Opt_context = 1, 305 Opt_fscontext = 2, 306 Opt_defcontext = 3, 307 Opt_rootcontext = 4, 308 Opt_labelsupport = 5, 309 }; 310 311 static const match_table_t tokens = { 312 {Opt_context, CONTEXT_STR "%s"}, 313 {Opt_fscontext, FSCONTEXT_STR "%s"}, 314 {Opt_defcontext, DEFCONTEXT_STR "%s"}, 315 {Opt_rootcontext, ROOTCONTEXT_STR "%s"}, 316 {Opt_labelsupport, LABELSUPP_STR}, 317 {Opt_error, NULL}, 318 }; 319 320 #define SEL_MOUNT_FAIL_MSG "SELinux: duplicate or incompatible mount options\n" 321 322 static int may_context_mount_sb_relabel(u32 sid, 323 struct superblock_security_struct *sbsec, 324 const struct cred *cred) 325 { 326 const struct task_security_struct *tsec = cred->security; 327 int rc; 328 329 rc = avc_has_perm(tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM, 330 FILESYSTEM__RELABELFROM, NULL); 331 if (rc) 332 return rc; 333 334 rc = avc_has_perm(tsec->sid, sid, SECCLASS_FILESYSTEM, 335 FILESYSTEM__RELABELTO, NULL); 336 return rc; 337 } 338 339 static int may_context_mount_inode_relabel(u32 sid, 340 struct superblock_security_struct *sbsec, 341 const struct cred *cred) 342 { 343 const struct task_security_struct *tsec = cred->security; 344 int rc; 345 rc = avc_has_perm(tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM, 346 FILESYSTEM__RELABELFROM, NULL); 347 if (rc) 348 return rc; 349 350 rc = avc_has_perm(sid, sbsec->sid, SECCLASS_FILESYSTEM, 351 FILESYSTEM__ASSOCIATE, NULL); 352 return rc; 353 } 354 355 static int sb_finish_set_opts(struct super_block *sb) 356 { 357 struct superblock_security_struct *sbsec = sb->s_security; 358 struct dentry *root = sb->s_root; 359 struct inode *root_inode = root->d_inode; 360 int rc = 0; 361 362 if (sbsec->behavior == SECURITY_FS_USE_XATTR) { 363 /* Make sure that the xattr handler exists and that no 364 error other than -ENODATA is returned by getxattr on 365 the root directory. -ENODATA is ok, as this may be 366 the first boot of the SELinux kernel before we have 367 assigned xattr values to the filesystem. */ 368 if (!root_inode->i_op->getxattr) { 369 printk(KERN_WARNING "SELinux: (dev %s, type %s) has no " 370 "xattr support\n", sb->s_id, sb->s_type->name); 371 rc = -EOPNOTSUPP; 372 goto out; 373 } 374 rc = root_inode->i_op->getxattr(root, XATTR_NAME_SELINUX, NULL, 0); 375 if (rc < 0 && rc != -ENODATA) { 376 if (rc == -EOPNOTSUPP) 377 printk(KERN_WARNING "SELinux: (dev %s, type " 378 "%s) has no security xattr handler\n", 379 sb->s_id, sb->s_type->name); 380 else 381 printk(KERN_WARNING "SELinux: (dev %s, type " 382 "%s) getxattr errno %d\n", sb->s_id, 383 sb->s_type->name, -rc); 384 goto out; 385 } 386 } 387 388 sbsec->flags |= (SE_SBINITIALIZED | SE_SBLABELSUPP); 389 390 if (sbsec->behavior > ARRAY_SIZE(labeling_behaviors)) 391 printk(KERN_ERR "SELinux: initialized (dev %s, type %s), unknown behavior\n", 392 sb->s_id, sb->s_type->name); 393 else 394 printk(KERN_DEBUG "SELinux: initialized (dev %s, type %s), %s\n", 395 sb->s_id, sb->s_type->name, 396 labeling_behaviors[sbsec->behavior-1]); 397 398 if (sbsec->behavior == SECURITY_FS_USE_GENFS || 399 sbsec->behavior == SECURITY_FS_USE_MNTPOINT || 400 sbsec->behavior == SECURITY_FS_USE_NONE || 401 sbsec->behavior > ARRAY_SIZE(labeling_behaviors)) 402 sbsec->flags &= ~SE_SBLABELSUPP; 403 404 /* Special handling for sysfs. Is genfs but also has setxattr handler*/ 405 if (strncmp(sb->s_type->name, "sysfs", sizeof("sysfs")) == 0) 406 sbsec->flags |= SE_SBLABELSUPP; 407 408 /* Initialize the root inode. */ 409 rc = inode_doinit_with_dentry(root_inode, root); 410 411 /* Initialize any other inodes associated with the superblock, e.g. 412 inodes created prior to initial policy load or inodes created 413 during get_sb by a pseudo filesystem that directly 414 populates itself. */ 415 spin_lock(&sbsec->isec_lock); 416 next_inode: 417 if (!list_empty(&sbsec->isec_head)) { 418 struct inode_security_struct *isec = 419 list_entry(sbsec->isec_head.next, 420 struct inode_security_struct, list); 421 struct inode *inode = isec->inode; 422 spin_unlock(&sbsec->isec_lock); 423 inode = igrab(inode); 424 if (inode) { 425 if (!IS_PRIVATE(inode)) 426 inode_doinit(inode); 427 iput(inode); 428 } 429 spin_lock(&sbsec->isec_lock); 430 list_del_init(&isec->list); 431 goto next_inode; 432 } 433 spin_unlock(&sbsec->isec_lock); 434 out: 435 return rc; 436 } 437 438 /* 439 * This function should allow an FS to ask what it's mount security 440 * options were so it can use those later for submounts, displaying 441 * mount options, or whatever. 442 */ 443 static int selinux_get_mnt_opts(const struct super_block *sb, 444 struct security_mnt_opts *opts) 445 { 446 int rc = 0, i; 447 struct superblock_security_struct *sbsec = sb->s_security; 448 char *context = NULL; 449 u32 len; 450 char tmp; 451 452 security_init_mnt_opts(opts); 453 454 if (!(sbsec->flags & SE_SBINITIALIZED)) 455 return -EINVAL; 456 457 if (!ss_initialized) 458 return -EINVAL; 459 460 tmp = sbsec->flags & SE_MNTMASK; 461 /* count the number of mount options for this sb */ 462 for (i = 0; i < 8; i++) { 463 if (tmp & 0x01) 464 opts->num_mnt_opts++; 465 tmp >>= 1; 466 } 467 /* Check if the Label support flag is set */ 468 if (sbsec->flags & SE_SBLABELSUPP) 469 opts->num_mnt_opts++; 470 471 opts->mnt_opts = kcalloc(opts->num_mnt_opts, sizeof(char *), GFP_ATOMIC); 472 if (!opts->mnt_opts) { 473 rc = -ENOMEM; 474 goto out_free; 475 } 476 477 opts->mnt_opts_flags = kcalloc(opts->num_mnt_opts, sizeof(int), GFP_ATOMIC); 478 if (!opts->mnt_opts_flags) { 479 rc = -ENOMEM; 480 goto out_free; 481 } 482 483 i = 0; 484 if (sbsec->flags & FSCONTEXT_MNT) { 485 rc = security_sid_to_context(sbsec->sid, &context, &len); 486 if (rc) 487 goto out_free; 488 opts->mnt_opts[i] = context; 489 opts->mnt_opts_flags[i++] = FSCONTEXT_MNT; 490 } 491 if (sbsec->flags & CONTEXT_MNT) { 492 rc = security_sid_to_context(sbsec->mntpoint_sid, &context, &len); 493 if (rc) 494 goto out_free; 495 opts->mnt_opts[i] = context; 496 opts->mnt_opts_flags[i++] = CONTEXT_MNT; 497 } 498 if (sbsec->flags & DEFCONTEXT_MNT) { 499 rc = security_sid_to_context(sbsec->def_sid, &context, &len); 500 if (rc) 501 goto out_free; 502 opts->mnt_opts[i] = context; 503 opts->mnt_opts_flags[i++] = DEFCONTEXT_MNT; 504 } 505 if (sbsec->flags & ROOTCONTEXT_MNT) { 506 struct inode *root = sbsec->sb->s_root->d_inode; 507 struct inode_security_struct *isec = root->i_security; 508 509 rc = security_sid_to_context(isec->sid, &context, &len); 510 if (rc) 511 goto out_free; 512 opts->mnt_opts[i] = context; 513 opts->mnt_opts_flags[i++] = ROOTCONTEXT_MNT; 514 } 515 if (sbsec->flags & SE_SBLABELSUPP) { 516 opts->mnt_opts[i] = NULL; 517 opts->mnt_opts_flags[i++] = SE_SBLABELSUPP; 518 } 519 520 BUG_ON(i != opts->num_mnt_opts); 521 522 return 0; 523 524 out_free: 525 security_free_mnt_opts(opts); 526 return rc; 527 } 528 529 static int bad_option(struct superblock_security_struct *sbsec, char flag, 530 u32 old_sid, u32 new_sid) 531 { 532 char mnt_flags = sbsec->flags & SE_MNTMASK; 533 534 /* check if the old mount command had the same options */ 535 if (sbsec->flags & SE_SBINITIALIZED) 536 if (!(sbsec->flags & flag) || 537 (old_sid != new_sid)) 538 return 1; 539 540 /* check if we were passed the same options twice, 541 * aka someone passed context=a,context=b 542 */ 543 if (!(sbsec->flags & SE_SBINITIALIZED)) 544 if (mnt_flags & flag) 545 return 1; 546 return 0; 547 } 548 549 /* 550 * Allow filesystems with binary mount data to explicitly set mount point 551 * labeling information. 552 */ 553 static int selinux_set_mnt_opts(struct super_block *sb, 554 struct security_mnt_opts *opts) 555 { 556 const struct cred *cred = current_cred(); 557 int rc = 0, i; 558 struct superblock_security_struct *sbsec = sb->s_security; 559 const char *name = sb->s_type->name; 560 struct inode *inode = sbsec->sb->s_root->d_inode; 561 struct inode_security_struct *root_isec = inode->i_security; 562 u32 fscontext_sid = 0, context_sid = 0, rootcontext_sid = 0; 563 u32 defcontext_sid = 0; 564 char **mount_options = opts->mnt_opts; 565 int *flags = opts->mnt_opts_flags; 566 int num_opts = opts->num_mnt_opts; 567 568 mutex_lock(&sbsec->lock); 569 570 if (!ss_initialized) { 571 if (!num_opts) { 572 /* Defer initialization until selinux_complete_init, 573 after the initial policy is loaded and the security 574 server is ready to handle calls. */ 575 goto out; 576 } 577 rc = -EINVAL; 578 printk(KERN_WARNING "SELinux: Unable to set superblock options " 579 "before the security server is initialized\n"); 580 goto out; 581 } 582 583 /* 584 * Binary mount data FS will come through this function twice. Once 585 * from an explicit call and once from the generic calls from the vfs. 586 * Since the generic VFS calls will not contain any security mount data 587 * we need to skip the double mount verification. 588 * 589 * This does open a hole in which we will not notice if the first 590 * mount using this sb set explict options and a second mount using 591 * this sb does not set any security options. (The first options 592 * will be used for both mounts) 593 */ 594 if ((sbsec->flags & SE_SBINITIALIZED) && (sb->s_type->fs_flags & FS_BINARY_MOUNTDATA) 595 && (num_opts == 0)) 596 goto out; 597 598 /* 599 * parse the mount options, check if they are valid sids. 600 * also check if someone is trying to mount the same sb more 601 * than once with different security options. 602 */ 603 for (i = 0; i < num_opts; i++) { 604 u32 sid; 605 606 if (flags[i] == SE_SBLABELSUPP) 607 continue; 608 rc = security_context_to_sid(mount_options[i], 609 strlen(mount_options[i]), &sid); 610 if (rc) { 611 printk(KERN_WARNING "SELinux: security_context_to_sid" 612 "(%s) failed for (dev %s, type %s) errno=%d\n", 613 mount_options[i], sb->s_id, name, rc); 614 goto out; 615 } 616 switch (flags[i]) { 617 case FSCONTEXT_MNT: 618 fscontext_sid = sid; 619 620 if (bad_option(sbsec, FSCONTEXT_MNT, sbsec->sid, 621 fscontext_sid)) 622 goto out_double_mount; 623 624 sbsec->flags |= FSCONTEXT_MNT; 625 break; 626 case CONTEXT_MNT: 627 context_sid = sid; 628 629 if (bad_option(sbsec, CONTEXT_MNT, sbsec->mntpoint_sid, 630 context_sid)) 631 goto out_double_mount; 632 633 sbsec->flags |= CONTEXT_MNT; 634 break; 635 case ROOTCONTEXT_MNT: 636 rootcontext_sid = sid; 637 638 if (bad_option(sbsec, ROOTCONTEXT_MNT, root_isec->sid, 639 rootcontext_sid)) 640 goto out_double_mount; 641 642 sbsec->flags |= ROOTCONTEXT_MNT; 643 644 break; 645 case DEFCONTEXT_MNT: 646 defcontext_sid = sid; 647 648 if (bad_option(sbsec, DEFCONTEXT_MNT, sbsec->def_sid, 649 defcontext_sid)) 650 goto out_double_mount; 651 652 sbsec->flags |= DEFCONTEXT_MNT; 653 654 break; 655 default: 656 rc = -EINVAL; 657 goto out; 658 } 659 } 660 661 if (sbsec->flags & SE_SBINITIALIZED) { 662 /* previously mounted with options, but not on this attempt? */ 663 if ((sbsec->flags & SE_MNTMASK) && !num_opts) 664 goto out_double_mount; 665 rc = 0; 666 goto out; 667 } 668 669 if (strcmp(sb->s_type->name, "proc") == 0) 670 sbsec->flags |= SE_SBPROC; 671 672 /* Determine the labeling behavior to use for this filesystem type. */ 673 rc = security_fs_use((sbsec->flags & SE_SBPROC) ? "proc" : sb->s_type->name, &sbsec->behavior, &sbsec->sid); 674 if (rc) { 675 printk(KERN_WARNING "%s: security_fs_use(%s) returned %d\n", 676 __func__, sb->s_type->name, rc); 677 goto out; 678 } 679 680 /* sets the context of the superblock for the fs being mounted. */ 681 if (fscontext_sid) { 682 rc = may_context_mount_sb_relabel(fscontext_sid, sbsec, cred); 683 if (rc) 684 goto out; 685 686 sbsec->sid = fscontext_sid; 687 } 688 689 /* 690 * Switch to using mount point labeling behavior. 691 * sets the label used on all file below the mountpoint, and will set 692 * the superblock context if not already set. 693 */ 694 if (context_sid) { 695 if (!fscontext_sid) { 696 rc = may_context_mount_sb_relabel(context_sid, sbsec, 697 cred); 698 if (rc) 699 goto out; 700 sbsec->sid = context_sid; 701 } else { 702 rc = may_context_mount_inode_relabel(context_sid, sbsec, 703 cred); 704 if (rc) 705 goto out; 706 } 707 if (!rootcontext_sid) 708 rootcontext_sid = context_sid; 709 710 sbsec->mntpoint_sid = context_sid; 711 sbsec->behavior = SECURITY_FS_USE_MNTPOINT; 712 } 713 714 if (rootcontext_sid) { 715 rc = may_context_mount_inode_relabel(rootcontext_sid, sbsec, 716 cred); 717 if (rc) 718 goto out; 719 720 root_isec->sid = rootcontext_sid; 721 root_isec->initialized = 1; 722 } 723 724 if (defcontext_sid) { 725 if (sbsec->behavior != SECURITY_FS_USE_XATTR) { 726 rc = -EINVAL; 727 printk(KERN_WARNING "SELinux: defcontext option is " 728 "invalid for this filesystem type\n"); 729 goto out; 730 } 731 732 if (defcontext_sid != sbsec->def_sid) { 733 rc = may_context_mount_inode_relabel(defcontext_sid, 734 sbsec, cred); 735 if (rc) 736 goto out; 737 } 738 739 sbsec->def_sid = defcontext_sid; 740 } 741 742 rc = sb_finish_set_opts(sb); 743 out: 744 mutex_unlock(&sbsec->lock); 745 return rc; 746 out_double_mount: 747 rc = -EINVAL; 748 printk(KERN_WARNING "SELinux: mount invalid. Same superblock, different " 749 "security settings for (dev %s, type %s)\n", sb->s_id, name); 750 goto out; 751 } 752 753 static void selinux_sb_clone_mnt_opts(const struct super_block *oldsb, 754 struct super_block *newsb) 755 { 756 const struct superblock_security_struct *oldsbsec = oldsb->s_security; 757 struct superblock_security_struct *newsbsec = newsb->s_security; 758 759 int set_fscontext = (oldsbsec->flags & FSCONTEXT_MNT); 760 int set_context = (oldsbsec->flags & CONTEXT_MNT); 761 int set_rootcontext = (oldsbsec->flags & ROOTCONTEXT_MNT); 762 763 /* 764 * if the parent was able to be mounted it clearly had no special lsm 765 * mount options. thus we can safely deal with this superblock later 766 */ 767 if (!ss_initialized) 768 return; 769 770 /* how can we clone if the old one wasn't set up?? */ 771 BUG_ON(!(oldsbsec->flags & SE_SBINITIALIZED)); 772 773 /* if fs is reusing a sb, just let its options stand... */ 774 if (newsbsec->flags & SE_SBINITIALIZED) 775 return; 776 777 mutex_lock(&newsbsec->lock); 778 779 newsbsec->flags = oldsbsec->flags; 780 781 newsbsec->sid = oldsbsec->sid; 782 newsbsec->def_sid = oldsbsec->def_sid; 783 newsbsec->behavior = oldsbsec->behavior; 784 785 if (set_context) { 786 u32 sid = oldsbsec->mntpoint_sid; 787 788 if (!set_fscontext) 789 newsbsec->sid = sid; 790 if (!set_rootcontext) { 791 struct inode *newinode = newsb->s_root->d_inode; 792 struct inode_security_struct *newisec = newinode->i_security; 793 newisec->sid = sid; 794 } 795 newsbsec->mntpoint_sid = sid; 796 } 797 if (set_rootcontext) { 798 const struct inode *oldinode = oldsb->s_root->d_inode; 799 const struct inode_security_struct *oldisec = oldinode->i_security; 800 struct inode *newinode = newsb->s_root->d_inode; 801 struct inode_security_struct *newisec = newinode->i_security; 802 803 newisec->sid = oldisec->sid; 804 } 805 806 sb_finish_set_opts(newsb); 807 mutex_unlock(&newsbsec->lock); 808 } 809 810 static int selinux_parse_opts_str(char *options, 811 struct security_mnt_opts *opts) 812 { 813 char *p; 814 char *context = NULL, *defcontext = NULL; 815 char *fscontext = NULL, *rootcontext = NULL; 816 int rc, num_mnt_opts = 0; 817 818 opts->num_mnt_opts = 0; 819 820 /* Standard string-based options. */ 821 while ((p = strsep(&options, "|")) != NULL) { 822 int token; 823 substring_t args[MAX_OPT_ARGS]; 824 825 if (!*p) 826 continue; 827 828 token = match_token(p, tokens, args); 829 830 switch (token) { 831 case Opt_context: 832 if (context || defcontext) { 833 rc = -EINVAL; 834 printk(KERN_WARNING SEL_MOUNT_FAIL_MSG); 835 goto out_err; 836 } 837 context = match_strdup(&args[0]); 838 if (!context) { 839 rc = -ENOMEM; 840 goto out_err; 841 } 842 break; 843 844 case Opt_fscontext: 845 if (fscontext) { 846 rc = -EINVAL; 847 printk(KERN_WARNING SEL_MOUNT_FAIL_MSG); 848 goto out_err; 849 } 850 fscontext = match_strdup(&args[0]); 851 if (!fscontext) { 852 rc = -ENOMEM; 853 goto out_err; 854 } 855 break; 856 857 case Opt_rootcontext: 858 if (rootcontext) { 859 rc = -EINVAL; 860 printk(KERN_WARNING SEL_MOUNT_FAIL_MSG); 861 goto out_err; 862 } 863 rootcontext = match_strdup(&args[0]); 864 if (!rootcontext) { 865 rc = -ENOMEM; 866 goto out_err; 867 } 868 break; 869 870 case Opt_defcontext: 871 if (context || defcontext) { 872 rc = -EINVAL; 873 printk(KERN_WARNING SEL_MOUNT_FAIL_MSG); 874 goto out_err; 875 } 876 defcontext = match_strdup(&args[0]); 877 if (!defcontext) { 878 rc = -ENOMEM; 879 goto out_err; 880 } 881 break; 882 case Opt_labelsupport: 883 break; 884 default: 885 rc = -EINVAL; 886 printk(KERN_WARNING "SELinux: unknown mount option\n"); 887 goto out_err; 888 889 } 890 } 891 892 rc = -ENOMEM; 893 opts->mnt_opts = kcalloc(NUM_SEL_MNT_OPTS, sizeof(char *), GFP_ATOMIC); 894 if (!opts->mnt_opts) 895 goto out_err; 896 897 opts->mnt_opts_flags = kcalloc(NUM_SEL_MNT_OPTS, sizeof(int), GFP_ATOMIC); 898 if (!opts->mnt_opts_flags) { 899 kfree(opts->mnt_opts); 900 goto out_err; 901 } 902 903 if (fscontext) { 904 opts->mnt_opts[num_mnt_opts] = fscontext; 905 opts->mnt_opts_flags[num_mnt_opts++] = FSCONTEXT_MNT; 906 } 907 if (context) { 908 opts->mnt_opts[num_mnt_opts] = context; 909 opts->mnt_opts_flags[num_mnt_opts++] = CONTEXT_MNT; 910 } 911 if (rootcontext) { 912 opts->mnt_opts[num_mnt_opts] = rootcontext; 913 opts->mnt_opts_flags[num_mnt_opts++] = ROOTCONTEXT_MNT; 914 } 915 if (defcontext) { 916 opts->mnt_opts[num_mnt_opts] = defcontext; 917 opts->mnt_opts_flags[num_mnt_opts++] = DEFCONTEXT_MNT; 918 } 919 920 opts->num_mnt_opts = num_mnt_opts; 921 return 0; 922 923 out_err: 924 kfree(context); 925 kfree(defcontext); 926 kfree(fscontext); 927 kfree(rootcontext); 928 return rc; 929 } 930 /* 931 * string mount options parsing and call set the sbsec 932 */ 933 static int superblock_doinit(struct super_block *sb, void *data) 934 { 935 int rc = 0; 936 char *options = data; 937 struct security_mnt_opts opts; 938 939 security_init_mnt_opts(&opts); 940 941 if (!data) 942 goto out; 943 944 BUG_ON(sb->s_type->fs_flags & FS_BINARY_MOUNTDATA); 945 946 rc = selinux_parse_opts_str(options, &opts); 947 if (rc) 948 goto out_err; 949 950 out: 951 rc = selinux_set_mnt_opts(sb, &opts); 952 953 out_err: 954 security_free_mnt_opts(&opts); 955 return rc; 956 } 957 958 static void selinux_write_opts(struct seq_file *m, 959 struct security_mnt_opts *opts) 960 { 961 int i; 962 char *prefix; 963 964 for (i = 0; i < opts->num_mnt_opts; i++) { 965 char *has_comma; 966 967 if (opts->mnt_opts[i]) 968 has_comma = strchr(opts->mnt_opts[i], ','); 969 else 970 has_comma = NULL; 971 972 switch (opts->mnt_opts_flags[i]) { 973 case CONTEXT_MNT: 974 prefix = CONTEXT_STR; 975 break; 976 case FSCONTEXT_MNT: 977 prefix = FSCONTEXT_STR; 978 break; 979 case ROOTCONTEXT_MNT: 980 prefix = ROOTCONTEXT_STR; 981 break; 982 case DEFCONTEXT_MNT: 983 prefix = DEFCONTEXT_STR; 984 break; 985 case SE_SBLABELSUPP: 986 seq_putc(m, ','); 987 seq_puts(m, LABELSUPP_STR); 988 continue; 989 default: 990 BUG(); 991 return; 992 }; 993 /* we need a comma before each option */ 994 seq_putc(m, ','); 995 seq_puts(m, prefix); 996 if (has_comma) 997 seq_putc(m, '\"'); 998 seq_puts(m, opts->mnt_opts[i]); 999 if (has_comma) 1000 seq_putc(m, '\"'); 1001 } 1002 } 1003 1004 static int selinux_sb_show_options(struct seq_file *m, struct super_block *sb) 1005 { 1006 struct security_mnt_opts opts; 1007 int rc; 1008 1009 rc = selinux_get_mnt_opts(sb, &opts); 1010 if (rc) { 1011 /* before policy load we may get EINVAL, don't show anything */ 1012 if (rc == -EINVAL) 1013 rc = 0; 1014 return rc; 1015 } 1016 1017 selinux_write_opts(m, &opts); 1018 1019 security_free_mnt_opts(&opts); 1020 1021 return rc; 1022 } 1023 1024 static inline u16 inode_mode_to_security_class(umode_t mode) 1025 { 1026 switch (mode & S_IFMT) { 1027 case S_IFSOCK: 1028 return SECCLASS_SOCK_FILE; 1029 case S_IFLNK: 1030 return SECCLASS_LNK_FILE; 1031 case S_IFREG: 1032 return SECCLASS_FILE; 1033 case S_IFBLK: 1034 return SECCLASS_BLK_FILE; 1035 case S_IFDIR: 1036 return SECCLASS_DIR; 1037 case S_IFCHR: 1038 return SECCLASS_CHR_FILE; 1039 case S_IFIFO: 1040 return SECCLASS_FIFO_FILE; 1041 1042 } 1043 1044 return SECCLASS_FILE; 1045 } 1046 1047 static inline int default_protocol_stream(int protocol) 1048 { 1049 return (protocol == IPPROTO_IP || protocol == IPPROTO_TCP); 1050 } 1051 1052 static inline int default_protocol_dgram(int protocol) 1053 { 1054 return (protocol == IPPROTO_IP || protocol == IPPROTO_UDP); 1055 } 1056 1057 static inline u16 socket_type_to_security_class(int family, int type, int protocol) 1058 { 1059 switch (family) { 1060 case PF_UNIX: 1061 switch (type) { 1062 case SOCK_STREAM: 1063 case SOCK_SEQPACKET: 1064 return SECCLASS_UNIX_STREAM_SOCKET; 1065 case SOCK_DGRAM: 1066 return SECCLASS_UNIX_DGRAM_SOCKET; 1067 } 1068 break; 1069 case PF_INET: 1070 case PF_INET6: 1071 switch (type) { 1072 case SOCK_STREAM: 1073 if (default_protocol_stream(protocol)) 1074 return SECCLASS_TCP_SOCKET; 1075 else 1076 return SECCLASS_RAWIP_SOCKET; 1077 case SOCK_DGRAM: 1078 if (default_protocol_dgram(protocol)) 1079 return SECCLASS_UDP_SOCKET; 1080 else 1081 return SECCLASS_RAWIP_SOCKET; 1082 case SOCK_DCCP: 1083 return SECCLASS_DCCP_SOCKET; 1084 default: 1085 return SECCLASS_RAWIP_SOCKET; 1086 } 1087 break; 1088 case PF_NETLINK: 1089 switch (protocol) { 1090 case NETLINK_ROUTE: 1091 return SECCLASS_NETLINK_ROUTE_SOCKET; 1092 case NETLINK_FIREWALL: 1093 return SECCLASS_NETLINK_FIREWALL_SOCKET; 1094 case NETLINK_SOCK_DIAG: 1095 return SECCLASS_NETLINK_TCPDIAG_SOCKET; 1096 case NETLINK_NFLOG: 1097 return SECCLASS_NETLINK_NFLOG_SOCKET; 1098 case NETLINK_XFRM: 1099 return SECCLASS_NETLINK_XFRM_SOCKET; 1100 case NETLINK_SELINUX: 1101 return SECCLASS_NETLINK_SELINUX_SOCKET; 1102 case NETLINK_AUDIT: 1103 return SECCLASS_NETLINK_AUDIT_SOCKET; 1104 case NETLINK_IP6_FW: 1105 return SECCLASS_NETLINK_IP6FW_SOCKET; 1106 case NETLINK_DNRTMSG: 1107 return SECCLASS_NETLINK_DNRT_SOCKET; 1108 case NETLINK_KOBJECT_UEVENT: 1109 return SECCLASS_NETLINK_KOBJECT_UEVENT_SOCKET; 1110 default: 1111 return SECCLASS_NETLINK_SOCKET; 1112 } 1113 case PF_PACKET: 1114 return SECCLASS_PACKET_SOCKET; 1115 case PF_KEY: 1116 return SECCLASS_KEY_SOCKET; 1117 case PF_APPLETALK: 1118 return SECCLASS_APPLETALK_SOCKET; 1119 } 1120 1121 return SECCLASS_SOCKET; 1122 } 1123 1124 #ifdef CONFIG_PROC_FS 1125 static int selinux_proc_get_sid(struct dentry *dentry, 1126 u16 tclass, 1127 u32 *sid) 1128 { 1129 int rc; 1130 char *buffer, *path; 1131 1132 buffer = (char *)__get_free_page(GFP_KERNEL); 1133 if (!buffer) 1134 return -ENOMEM; 1135 1136 path = dentry_path_raw(dentry, buffer, PAGE_SIZE); 1137 if (IS_ERR(path)) 1138 rc = PTR_ERR(path); 1139 else { 1140 /* each process gets a /proc/PID/ entry. Strip off the 1141 * PID part to get a valid selinux labeling. 1142 * e.g. /proc/1/net/rpc/nfs -> /net/rpc/nfs */ 1143 while (path[1] >= '0' && path[1] <= '9') { 1144 path[1] = '/'; 1145 path++; 1146 } 1147 rc = security_genfs_sid("proc", path, tclass, sid); 1148 } 1149 free_page((unsigned long)buffer); 1150 return rc; 1151 } 1152 #else 1153 static int selinux_proc_get_sid(struct dentry *dentry, 1154 u16 tclass, 1155 u32 *sid) 1156 { 1157 return -EINVAL; 1158 } 1159 #endif 1160 1161 /* The inode's security attributes must be initialized before first use. */ 1162 static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dentry) 1163 { 1164 struct superblock_security_struct *sbsec = NULL; 1165 struct inode_security_struct *isec = inode->i_security; 1166 u32 sid; 1167 struct dentry *dentry; 1168 #define INITCONTEXTLEN 255 1169 char *context = NULL; 1170 unsigned len = 0; 1171 int rc = 0; 1172 1173 if (isec->initialized) 1174 goto out; 1175 1176 mutex_lock(&isec->lock); 1177 if (isec->initialized) 1178 goto out_unlock; 1179 1180 sbsec = inode->i_sb->s_security; 1181 if (!(sbsec->flags & SE_SBINITIALIZED)) { 1182 /* Defer initialization until selinux_complete_init, 1183 after the initial policy is loaded and the security 1184 server is ready to handle calls. */ 1185 spin_lock(&sbsec->isec_lock); 1186 if (list_empty(&isec->list)) 1187 list_add(&isec->list, &sbsec->isec_head); 1188 spin_unlock(&sbsec->isec_lock); 1189 goto out_unlock; 1190 } 1191 1192 switch (sbsec->behavior) { 1193 case SECURITY_FS_USE_XATTR: 1194 if (!inode->i_op->getxattr) { 1195 isec->sid = sbsec->def_sid; 1196 break; 1197 } 1198 1199 /* Need a dentry, since the xattr API requires one. 1200 Life would be simpler if we could just pass the inode. */ 1201 if (opt_dentry) { 1202 /* Called from d_instantiate or d_splice_alias. */ 1203 dentry = dget(opt_dentry); 1204 } else { 1205 /* Called from selinux_complete_init, try to find a dentry. */ 1206 dentry = d_find_alias(inode); 1207 } 1208 if (!dentry) { 1209 /* 1210 * this is can be hit on boot when a file is accessed 1211 * before the policy is loaded. When we load policy we 1212 * may find inodes that have no dentry on the 1213 * sbsec->isec_head list. No reason to complain as these 1214 * will get fixed up the next time we go through 1215 * inode_doinit with a dentry, before these inodes could 1216 * be used again by userspace. 1217 */ 1218 goto out_unlock; 1219 } 1220 1221 len = INITCONTEXTLEN; 1222 context = kmalloc(len+1, GFP_NOFS); 1223 if (!context) { 1224 rc = -ENOMEM; 1225 dput(dentry); 1226 goto out_unlock; 1227 } 1228 context[len] = '\0'; 1229 rc = inode->i_op->getxattr(dentry, XATTR_NAME_SELINUX, 1230 context, len); 1231 if (rc == -ERANGE) { 1232 kfree(context); 1233 1234 /* Need a larger buffer. Query for the right size. */ 1235 rc = inode->i_op->getxattr(dentry, XATTR_NAME_SELINUX, 1236 NULL, 0); 1237 if (rc < 0) { 1238 dput(dentry); 1239 goto out_unlock; 1240 } 1241 len = rc; 1242 context = kmalloc(len+1, GFP_NOFS); 1243 if (!context) { 1244 rc = -ENOMEM; 1245 dput(dentry); 1246 goto out_unlock; 1247 } 1248 context[len] = '\0'; 1249 rc = inode->i_op->getxattr(dentry, 1250 XATTR_NAME_SELINUX, 1251 context, len); 1252 } 1253 dput(dentry); 1254 if (rc < 0) { 1255 if (rc != -ENODATA) { 1256 printk(KERN_WARNING "SELinux: %s: getxattr returned " 1257 "%d for dev=%s ino=%ld\n", __func__, 1258 -rc, inode->i_sb->s_id, inode->i_ino); 1259 kfree(context); 1260 goto out_unlock; 1261 } 1262 /* Map ENODATA to the default file SID */ 1263 sid = sbsec->def_sid; 1264 rc = 0; 1265 } else { 1266 rc = security_context_to_sid_default(context, rc, &sid, 1267 sbsec->def_sid, 1268 GFP_NOFS); 1269 if (rc) { 1270 char *dev = inode->i_sb->s_id; 1271 unsigned long ino = inode->i_ino; 1272 1273 if (rc == -EINVAL) { 1274 if (printk_ratelimit()) 1275 printk(KERN_NOTICE "SELinux: inode=%lu on dev=%s was found to have an invalid " 1276 "context=%s. This indicates you may need to relabel the inode or the " 1277 "filesystem in question.\n", ino, dev, context); 1278 } else { 1279 printk(KERN_WARNING "SELinux: %s: context_to_sid(%s) " 1280 "returned %d for dev=%s ino=%ld\n", 1281 __func__, context, -rc, dev, ino); 1282 } 1283 kfree(context); 1284 /* Leave with the unlabeled SID */ 1285 rc = 0; 1286 break; 1287 } 1288 } 1289 kfree(context); 1290 isec->sid = sid; 1291 break; 1292 case SECURITY_FS_USE_TASK: 1293 isec->sid = isec->task_sid; 1294 break; 1295 case SECURITY_FS_USE_TRANS: 1296 /* Default to the fs SID. */ 1297 isec->sid = sbsec->sid; 1298 1299 /* Try to obtain a transition SID. */ 1300 isec->sclass = inode_mode_to_security_class(inode->i_mode); 1301 rc = security_transition_sid(isec->task_sid, sbsec->sid, 1302 isec->sclass, NULL, &sid); 1303 if (rc) 1304 goto out_unlock; 1305 isec->sid = sid; 1306 break; 1307 case SECURITY_FS_USE_MNTPOINT: 1308 isec->sid = sbsec->mntpoint_sid; 1309 break; 1310 default: 1311 /* Default to the fs superblock SID. */ 1312 isec->sid = sbsec->sid; 1313 1314 if ((sbsec->flags & SE_SBPROC) && !S_ISLNK(inode->i_mode)) { 1315 if (opt_dentry) { 1316 isec->sclass = inode_mode_to_security_class(inode->i_mode); 1317 rc = selinux_proc_get_sid(opt_dentry, 1318 isec->sclass, 1319 &sid); 1320 if (rc) 1321 goto out_unlock; 1322 isec->sid = sid; 1323 } 1324 } 1325 break; 1326 } 1327 1328 isec->initialized = 1; 1329 1330 out_unlock: 1331 mutex_unlock(&isec->lock); 1332 out: 1333 if (isec->sclass == SECCLASS_FILE) 1334 isec->sclass = inode_mode_to_security_class(inode->i_mode); 1335 return rc; 1336 } 1337 1338 /* Convert a Linux signal to an access vector. */ 1339 static inline u32 signal_to_av(int sig) 1340 { 1341 u32 perm = 0; 1342 1343 switch (sig) { 1344 case SIGCHLD: 1345 /* Commonly granted from child to parent. */ 1346 perm = PROCESS__SIGCHLD; 1347 break; 1348 case SIGKILL: 1349 /* Cannot be caught or ignored */ 1350 perm = PROCESS__SIGKILL; 1351 break; 1352 case SIGSTOP: 1353 /* Cannot be caught or ignored */ 1354 perm = PROCESS__SIGSTOP; 1355 break; 1356 default: 1357 /* All other signals. */ 1358 perm = PROCESS__SIGNAL; 1359 break; 1360 } 1361 1362 return perm; 1363 } 1364 1365 /* 1366 * Check permission between a pair of credentials 1367 * fork check, ptrace check, etc. 1368 */ 1369 static int cred_has_perm(const struct cred *actor, 1370 const struct cred *target, 1371 u32 perms) 1372 { 1373 u32 asid = cred_sid(actor), tsid = cred_sid(target); 1374 1375 return avc_has_perm(asid, tsid, SECCLASS_PROCESS, perms, NULL); 1376 } 1377 1378 /* 1379 * Check permission between a pair of tasks, e.g. signal checks, 1380 * fork check, ptrace check, etc. 1381 * tsk1 is the actor and tsk2 is the target 1382 * - this uses the default subjective creds of tsk1 1383 */ 1384 static int task_has_perm(const struct task_struct *tsk1, 1385 const struct task_struct *tsk2, 1386 u32 perms) 1387 { 1388 const struct task_security_struct *__tsec1, *__tsec2; 1389 u32 sid1, sid2; 1390 1391 rcu_read_lock(); 1392 __tsec1 = __task_cred(tsk1)->security; sid1 = __tsec1->sid; 1393 __tsec2 = __task_cred(tsk2)->security; sid2 = __tsec2->sid; 1394 rcu_read_unlock(); 1395 return avc_has_perm(sid1, sid2, SECCLASS_PROCESS, perms, NULL); 1396 } 1397 1398 /* 1399 * Check permission between current and another task, e.g. signal checks, 1400 * fork check, ptrace check, etc. 1401 * current is the actor and tsk2 is the target 1402 * - this uses current's subjective creds 1403 */ 1404 static int current_has_perm(const struct task_struct *tsk, 1405 u32 perms) 1406 { 1407 u32 sid, tsid; 1408 1409 sid = current_sid(); 1410 tsid = task_sid(tsk); 1411 return avc_has_perm(sid, tsid, SECCLASS_PROCESS, perms, NULL); 1412 } 1413 1414 #if CAP_LAST_CAP > 63 1415 #error Fix SELinux to handle capabilities > 63. 1416 #endif 1417 1418 /* Check whether a task is allowed to use a capability. */ 1419 static int cred_has_capability(const struct cred *cred, 1420 int cap, int audit) 1421 { 1422 struct common_audit_data ad; 1423 struct selinux_audit_data sad = {0,}; 1424 struct av_decision avd; 1425 u16 sclass; 1426 u32 sid = cred_sid(cred); 1427 u32 av = CAP_TO_MASK(cap); 1428 int rc; 1429 1430 COMMON_AUDIT_DATA_INIT(&ad, CAP); 1431 ad.selinux_audit_data = &sad; 1432 ad.tsk = current; 1433 ad.u.cap = cap; 1434 1435 switch (CAP_TO_INDEX(cap)) { 1436 case 0: 1437 sclass = SECCLASS_CAPABILITY; 1438 break; 1439 case 1: 1440 sclass = SECCLASS_CAPABILITY2; 1441 break; 1442 default: 1443 printk(KERN_ERR 1444 "SELinux: out of range capability %d\n", cap); 1445 BUG(); 1446 return -EINVAL; 1447 } 1448 1449 rc = avc_has_perm_noaudit(sid, sid, sclass, av, 0, &avd); 1450 if (audit == SECURITY_CAP_AUDIT) { 1451 int rc2 = avc_audit(sid, sid, sclass, av, &avd, rc, &ad, 0); 1452 if (rc2) 1453 return rc2; 1454 } 1455 return rc; 1456 } 1457 1458 /* Check whether a task is allowed to use a system operation. */ 1459 static int task_has_system(struct task_struct *tsk, 1460 u32 perms) 1461 { 1462 u32 sid = task_sid(tsk); 1463 1464 return avc_has_perm(sid, SECINITSID_KERNEL, 1465 SECCLASS_SYSTEM, perms, NULL); 1466 } 1467 1468 /* Check whether a task has a particular permission to an inode. 1469 The 'adp' parameter is optional and allows other audit 1470 data to be passed (e.g. the dentry). */ 1471 static int inode_has_perm(const struct cred *cred, 1472 struct inode *inode, 1473 u32 perms, 1474 struct common_audit_data *adp, 1475 unsigned flags) 1476 { 1477 struct inode_security_struct *isec; 1478 u32 sid; 1479 1480 validate_creds(cred); 1481 1482 if (unlikely(IS_PRIVATE(inode))) 1483 return 0; 1484 1485 sid = cred_sid(cred); 1486 isec = inode->i_security; 1487 1488 return avc_has_perm_flags(sid, isec->sid, isec->sclass, perms, adp, flags); 1489 } 1490 1491 static int inode_has_perm_noadp(const struct cred *cred, 1492 struct inode *inode, 1493 u32 perms, 1494 unsigned flags) 1495 { 1496 struct common_audit_data ad; 1497 struct selinux_audit_data sad = {0,}; 1498 1499 COMMON_AUDIT_DATA_INIT(&ad, INODE); 1500 ad.u.inode = inode; 1501 ad.selinux_audit_data = &sad; 1502 return inode_has_perm(cred, inode, perms, &ad, flags); 1503 } 1504 1505 /* Same as inode_has_perm, but pass explicit audit data containing 1506 the dentry to help the auditing code to more easily generate the 1507 pathname if needed. */ 1508 static inline int dentry_has_perm(const struct cred *cred, 1509 struct dentry *dentry, 1510 u32 av) 1511 { 1512 struct inode *inode = dentry->d_inode; 1513 struct common_audit_data ad; 1514 struct selinux_audit_data sad = {0,}; 1515 1516 COMMON_AUDIT_DATA_INIT(&ad, DENTRY); 1517 ad.u.dentry = dentry; 1518 ad.selinux_audit_data = &sad; 1519 return inode_has_perm(cred, inode, av, &ad, 0); 1520 } 1521 1522 /* Same as inode_has_perm, but pass explicit audit data containing 1523 the path to help the auditing code to more easily generate the 1524 pathname if needed. */ 1525 static inline int path_has_perm(const struct cred *cred, 1526 struct path *path, 1527 u32 av) 1528 { 1529 struct inode *inode = path->dentry->d_inode; 1530 struct common_audit_data ad; 1531 struct selinux_audit_data sad = {0,}; 1532 1533 COMMON_AUDIT_DATA_INIT(&ad, PATH); 1534 ad.u.path = *path; 1535 ad.selinux_audit_data = &sad; 1536 return inode_has_perm(cred, inode, av, &ad, 0); 1537 } 1538 1539 /* Check whether a task can use an open file descriptor to 1540 access an inode in a given way. Check access to the 1541 descriptor itself, and then use dentry_has_perm to 1542 check a particular permission to the file. 1543 Access to the descriptor is implicitly granted if it 1544 has the same SID as the process. If av is zero, then 1545 access to the file is not checked, e.g. for cases 1546 where only the descriptor is affected like seek. */ 1547 static int file_has_perm(const struct cred *cred, 1548 struct file *file, 1549 u32 av) 1550 { 1551 struct file_security_struct *fsec = file->f_security; 1552 struct inode *inode = file->f_path.dentry->d_inode; 1553 struct common_audit_data ad; 1554 struct selinux_audit_data sad = {0,}; 1555 u32 sid = cred_sid(cred); 1556 int rc; 1557 1558 COMMON_AUDIT_DATA_INIT(&ad, PATH); 1559 ad.u.path = file->f_path; 1560 ad.selinux_audit_data = &sad; 1561 1562 if (sid != fsec->sid) { 1563 rc = avc_has_perm(sid, fsec->sid, 1564 SECCLASS_FD, 1565 FD__USE, 1566 &ad); 1567 if (rc) 1568 goto out; 1569 } 1570 1571 /* av is zero if only checking access to the descriptor. */ 1572 rc = 0; 1573 if (av) 1574 rc = inode_has_perm(cred, inode, av, &ad, 0); 1575 1576 out: 1577 return rc; 1578 } 1579 1580 /* Check whether a task can create a file. */ 1581 static int may_create(struct inode *dir, 1582 struct dentry *dentry, 1583 u16 tclass) 1584 { 1585 const struct task_security_struct *tsec = current_security(); 1586 struct inode_security_struct *dsec; 1587 struct superblock_security_struct *sbsec; 1588 u32 sid, newsid; 1589 struct common_audit_data ad; 1590 struct selinux_audit_data sad = {0,}; 1591 int rc; 1592 1593 dsec = dir->i_security; 1594 sbsec = dir->i_sb->s_security; 1595 1596 sid = tsec->sid; 1597 newsid = tsec->create_sid; 1598 1599 COMMON_AUDIT_DATA_INIT(&ad, DENTRY); 1600 ad.u.dentry = dentry; 1601 ad.selinux_audit_data = &sad; 1602 1603 rc = avc_has_perm(sid, dsec->sid, SECCLASS_DIR, 1604 DIR__ADD_NAME | DIR__SEARCH, 1605 &ad); 1606 if (rc) 1607 return rc; 1608 1609 if (!newsid || !(sbsec->flags & SE_SBLABELSUPP)) { 1610 rc = security_transition_sid(sid, dsec->sid, tclass, 1611 &dentry->d_name, &newsid); 1612 if (rc) 1613 return rc; 1614 } 1615 1616 rc = avc_has_perm(sid, newsid, tclass, FILE__CREATE, &ad); 1617 if (rc) 1618 return rc; 1619 1620 return avc_has_perm(newsid, sbsec->sid, 1621 SECCLASS_FILESYSTEM, 1622 FILESYSTEM__ASSOCIATE, &ad); 1623 } 1624 1625 /* Check whether a task can create a key. */ 1626 static int may_create_key(u32 ksid, 1627 struct task_struct *ctx) 1628 { 1629 u32 sid = task_sid(ctx); 1630 1631 return avc_has_perm(sid, ksid, SECCLASS_KEY, KEY__CREATE, NULL); 1632 } 1633 1634 #define MAY_LINK 0 1635 #define MAY_UNLINK 1 1636 #define MAY_RMDIR 2 1637 1638 /* Check whether a task can link, unlink, or rmdir a file/directory. */ 1639 static int may_link(struct inode *dir, 1640 struct dentry *dentry, 1641 int kind) 1642 1643 { 1644 struct inode_security_struct *dsec, *isec; 1645 struct common_audit_data ad; 1646 struct selinux_audit_data sad = {0,}; 1647 u32 sid = current_sid(); 1648 u32 av; 1649 int rc; 1650 1651 dsec = dir->i_security; 1652 isec = dentry->d_inode->i_security; 1653 1654 COMMON_AUDIT_DATA_INIT(&ad, DENTRY); 1655 ad.u.dentry = dentry; 1656 ad.selinux_audit_data = &sad; 1657 1658 av = DIR__SEARCH; 1659 av |= (kind ? DIR__REMOVE_NAME : DIR__ADD_NAME); 1660 rc = avc_has_perm(sid, dsec->sid, SECCLASS_DIR, av, &ad); 1661 if (rc) 1662 return rc; 1663 1664 switch (kind) { 1665 case MAY_LINK: 1666 av = FILE__LINK; 1667 break; 1668 case MAY_UNLINK: 1669 av = FILE__UNLINK; 1670 break; 1671 case MAY_RMDIR: 1672 av = DIR__RMDIR; 1673 break; 1674 default: 1675 printk(KERN_WARNING "SELinux: %s: unrecognized kind %d\n", 1676 __func__, kind); 1677 return 0; 1678 } 1679 1680 rc = avc_has_perm(sid, isec->sid, isec->sclass, av, &ad); 1681 return rc; 1682 } 1683 1684 static inline int may_rename(struct inode *old_dir, 1685 struct dentry *old_dentry, 1686 struct inode *new_dir, 1687 struct dentry *new_dentry) 1688 { 1689 struct inode_security_struct *old_dsec, *new_dsec, *old_isec, *new_isec; 1690 struct common_audit_data ad; 1691 struct selinux_audit_data sad = {0,}; 1692 u32 sid = current_sid(); 1693 u32 av; 1694 int old_is_dir, new_is_dir; 1695 int rc; 1696 1697 old_dsec = old_dir->i_security; 1698 old_isec = old_dentry->d_inode->i_security; 1699 old_is_dir = S_ISDIR(old_dentry->d_inode->i_mode); 1700 new_dsec = new_dir->i_security; 1701 1702 COMMON_AUDIT_DATA_INIT(&ad, DENTRY); 1703 ad.selinux_audit_data = &sad; 1704 1705 ad.u.dentry = old_dentry; 1706 rc = avc_has_perm(sid, old_dsec->sid, SECCLASS_DIR, 1707 DIR__REMOVE_NAME | DIR__SEARCH, &ad); 1708 if (rc) 1709 return rc; 1710 rc = avc_has_perm(sid, old_isec->sid, 1711 old_isec->sclass, FILE__RENAME, &ad); 1712 if (rc) 1713 return rc; 1714 if (old_is_dir && new_dir != old_dir) { 1715 rc = avc_has_perm(sid, old_isec->sid, 1716 old_isec->sclass, DIR__REPARENT, &ad); 1717 if (rc) 1718 return rc; 1719 } 1720 1721 ad.u.dentry = new_dentry; 1722 av = DIR__ADD_NAME | DIR__SEARCH; 1723 if (new_dentry->d_inode) 1724 av |= DIR__REMOVE_NAME; 1725 rc = avc_has_perm(sid, new_dsec->sid, SECCLASS_DIR, av, &ad); 1726 if (rc) 1727 return rc; 1728 if (new_dentry->d_inode) { 1729 new_isec = new_dentry->d_inode->i_security; 1730 new_is_dir = S_ISDIR(new_dentry->d_inode->i_mode); 1731 rc = avc_has_perm(sid, new_isec->sid, 1732 new_isec->sclass, 1733 (new_is_dir ? DIR__RMDIR : FILE__UNLINK), &ad); 1734 if (rc) 1735 return rc; 1736 } 1737 1738 return 0; 1739 } 1740 1741 /* Check whether a task can perform a filesystem operation. */ 1742 static int superblock_has_perm(const struct cred *cred, 1743 struct super_block *sb, 1744 u32 perms, 1745 struct common_audit_data *ad) 1746 { 1747 struct superblock_security_struct *sbsec; 1748 u32 sid = cred_sid(cred); 1749 1750 sbsec = sb->s_security; 1751 return avc_has_perm(sid, sbsec->sid, SECCLASS_FILESYSTEM, perms, ad); 1752 } 1753 1754 /* Convert a Linux mode and permission mask to an access vector. */ 1755 static inline u32 file_mask_to_av(int mode, int mask) 1756 { 1757 u32 av = 0; 1758 1759 if (!S_ISDIR(mode)) { 1760 if (mask & MAY_EXEC) 1761 av |= FILE__EXECUTE; 1762 if (mask & MAY_READ) 1763 av |= FILE__READ; 1764 1765 if (mask & MAY_APPEND) 1766 av |= FILE__APPEND; 1767 else if (mask & MAY_WRITE) 1768 av |= FILE__WRITE; 1769 1770 } else { 1771 if (mask & MAY_EXEC) 1772 av |= DIR__SEARCH; 1773 if (mask & MAY_WRITE) 1774 av |= DIR__WRITE; 1775 if (mask & MAY_READ) 1776 av |= DIR__READ; 1777 } 1778 1779 return av; 1780 } 1781 1782 /* Convert a Linux file to an access vector. */ 1783 static inline u32 file_to_av(struct file *file) 1784 { 1785 u32 av = 0; 1786 1787 if (file->f_mode & FMODE_READ) 1788 av |= FILE__READ; 1789 if (file->f_mode & FMODE_WRITE) { 1790 if (file->f_flags & O_APPEND) 1791 av |= FILE__APPEND; 1792 else 1793 av |= FILE__WRITE; 1794 } 1795 if (!av) { 1796 /* 1797 * Special file opened with flags 3 for ioctl-only use. 1798 */ 1799 av = FILE__IOCTL; 1800 } 1801 1802 return av; 1803 } 1804 1805 /* 1806 * Convert a file to an access vector and include the correct open 1807 * open permission. 1808 */ 1809 static inline u32 open_file_to_av(struct file *file) 1810 { 1811 u32 av = file_to_av(file); 1812 1813 if (selinux_policycap_openperm) 1814 av |= FILE__OPEN; 1815 1816 return av; 1817 } 1818 1819 /* Hook functions begin here. */ 1820 1821 static int selinux_ptrace_access_check(struct task_struct *child, 1822 unsigned int mode) 1823 { 1824 int rc; 1825 1826 rc = cap_ptrace_access_check(child, mode); 1827 if (rc) 1828 return rc; 1829 1830 if (mode & PTRACE_MODE_READ) { 1831 u32 sid = current_sid(); 1832 u32 csid = task_sid(child); 1833 return avc_has_perm(sid, csid, SECCLASS_FILE, FILE__READ, NULL); 1834 } 1835 1836 return current_has_perm(child, PROCESS__PTRACE); 1837 } 1838 1839 static int selinux_ptrace_traceme(struct task_struct *parent) 1840 { 1841 int rc; 1842 1843 rc = cap_ptrace_traceme(parent); 1844 if (rc) 1845 return rc; 1846 1847 return task_has_perm(parent, current, PROCESS__PTRACE); 1848 } 1849 1850 static int selinux_capget(struct task_struct *target, kernel_cap_t *effective, 1851 kernel_cap_t *inheritable, kernel_cap_t *permitted) 1852 { 1853 int error; 1854 1855 error = current_has_perm(target, PROCESS__GETCAP); 1856 if (error) 1857 return error; 1858 1859 return cap_capget(target, effective, inheritable, permitted); 1860 } 1861 1862 static int selinux_capset(struct cred *new, const struct cred *old, 1863 const kernel_cap_t *effective, 1864 const kernel_cap_t *inheritable, 1865 const kernel_cap_t *permitted) 1866 { 1867 int error; 1868 1869 error = cap_capset(new, old, 1870 effective, inheritable, permitted); 1871 if (error) 1872 return error; 1873 1874 return cred_has_perm(old, new, PROCESS__SETCAP); 1875 } 1876 1877 /* 1878 * (This comment used to live with the selinux_task_setuid hook, 1879 * which was removed). 1880 * 1881 * Since setuid only affects the current process, and since the SELinux 1882 * controls are not based on the Linux identity attributes, SELinux does not 1883 * need to control this operation. However, SELinux does control the use of 1884 * the CAP_SETUID and CAP_SETGID capabilities using the capable hook. 1885 */ 1886 1887 static int selinux_capable(const struct cred *cred, struct user_namespace *ns, 1888 int cap, int audit) 1889 { 1890 int rc; 1891 1892 rc = cap_capable(cred, ns, cap, audit); 1893 if (rc) 1894 return rc; 1895 1896 return cred_has_capability(cred, cap, audit); 1897 } 1898 1899 static int selinux_quotactl(int cmds, int type, int id, struct super_block *sb) 1900 { 1901 const struct cred *cred = current_cred(); 1902 int rc = 0; 1903 1904 if (!sb) 1905 return 0; 1906 1907 switch (cmds) { 1908 case Q_SYNC: 1909 case Q_QUOTAON: 1910 case Q_QUOTAOFF: 1911 case Q_SETINFO: 1912 case Q_SETQUOTA: 1913 rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAMOD, NULL); 1914 break; 1915 case Q_GETFMT: 1916 case Q_GETINFO: 1917 case Q_GETQUOTA: 1918 rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAGET, NULL); 1919 break; 1920 default: 1921 rc = 0; /* let the kernel handle invalid cmds */ 1922 break; 1923 } 1924 return rc; 1925 } 1926 1927 static int selinux_quota_on(struct dentry *dentry) 1928 { 1929 const struct cred *cred = current_cred(); 1930 1931 return dentry_has_perm(cred, dentry, FILE__QUOTAON); 1932 } 1933 1934 static int selinux_syslog(int type) 1935 { 1936 int rc; 1937 1938 switch (type) { 1939 case SYSLOG_ACTION_READ_ALL: /* Read last kernel messages */ 1940 case SYSLOG_ACTION_SIZE_BUFFER: /* Return size of the log buffer */ 1941 rc = task_has_system(current, SYSTEM__SYSLOG_READ); 1942 break; 1943 case SYSLOG_ACTION_CONSOLE_OFF: /* Disable logging to console */ 1944 case SYSLOG_ACTION_CONSOLE_ON: /* Enable logging to console */ 1945 /* Set level of messages printed to console */ 1946 case SYSLOG_ACTION_CONSOLE_LEVEL: 1947 rc = task_has_system(current, SYSTEM__SYSLOG_CONSOLE); 1948 break; 1949 case SYSLOG_ACTION_CLOSE: /* Close log */ 1950 case SYSLOG_ACTION_OPEN: /* Open log */ 1951 case SYSLOG_ACTION_READ: /* Read from log */ 1952 case SYSLOG_ACTION_READ_CLEAR: /* Read/clear last kernel messages */ 1953 case SYSLOG_ACTION_CLEAR: /* Clear ring buffer */ 1954 default: 1955 rc = task_has_system(current, SYSTEM__SYSLOG_MOD); 1956 break; 1957 } 1958 return rc; 1959 } 1960 1961 /* 1962 * Check that a process has enough memory to allocate a new virtual 1963 * mapping. 0 means there is enough memory for the allocation to 1964 * succeed and -ENOMEM implies there is not. 1965 * 1966 * Do not audit the selinux permission check, as this is applied to all 1967 * processes that allocate mappings. 1968 */ 1969 static int selinux_vm_enough_memory(struct mm_struct *mm, long pages) 1970 { 1971 int rc, cap_sys_admin = 0; 1972 1973 rc = selinux_capable(current_cred(), &init_user_ns, CAP_SYS_ADMIN, 1974 SECURITY_CAP_NOAUDIT); 1975 if (rc == 0) 1976 cap_sys_admin = 1; 1977 1978 return __vm_enough_memory(mm, pages, cap_sys_admin); 1979 } 1980 1981 /* binprm security operations */ 1982 1983 static int selinux_bprm_set_creds(struct linux_binprm *bprm) 1984 { 1985 const struct task_security_struct *old_tsec; 1986 struct task_security_struct *new_tsec; 1987 struct inode_security_struct *isec; 1988 struct common_audit_data ad; 1989 struct selinux_audit_data sad = {0,}; 1990 struct inode *inode = bprm->file->f_path.dentry->d_inode; 1991 int rc; 1992 1993 rc = cap_bprm_set_creds(bprm); 1994 if (rc) 1995 return rc; 1996 1997 /* SELinux context only depends on initial program or script and not 1998 * the script interpreter */ 1999 if (bprm->cred_prepared) 2000 return 0; 2001 2002 old_tsec = current_security(); 2003 new_tsec = bprm->cred->security; 2004 isec = inode->i_security; 2005 2006 /* Default to the current task SID. */ 2007 new_tsec->sid = old_tsec->sid; 2008 new_tsec->osid = old_tsec->sid; 2009 2010 /* Reset fs, key, and sock SIDs on execve. */ 2011 new_tsec->create_sid = 0; 2012 new_tsec->keycreate_sid = 0; 2013 new_tsec->sockcreate_sid = 0; 2014 2015 if (old_tsec->exec_sid) { 2016 new_tsec->sid = old_tsec->exec_sid; 2017 /* Reset exec SID on execve. */ 2018 new_tsec->exec_sid = 0; 2019 2020 /* 2021 * Minimize confusion: if no_new_privs and a transition is 2022 * explicitly requested, then fail the exec. 2023 */ 2024 if (bprm->unsafe & LSM_UNSAFE_NO_NEW_PRIVS) 2025 return -EPERM; 2026 } else { 2027 /* Check for a default transition on this program. */ 2028 rc = security_transition_sid(old_tsec->sid, isec->sid, 2029 SECCLASS_PROCESS, NULL, 2030 &new_tsec->sid); 2031 if (rc) 2032 return rc; 2033 } 2034 2035 COMMON_AUDIT_DATA_INIT(&ad, PATH); 2036 ad.selinux_audit_data = &sad; 2037 ad.u.path = bprm->file->f_path; 2038 2039 if ((bprm->file->f_path.mnt->mnt_flags & MNT_NOSUID) || 2040 (bprm->unsafe & LSM_UNSAFE_NO_NEW_PRIVS)) 2041 new_tsec->sid = old_tsec->sid; 2042 2043 if (new_tsec->sid == old_tsec->sid) { 2044 rc = avc_has_perm(old_tsec->sid, isec->sid, 2045 SECCLASS_FILE, FILE__EXECUTE_NO_TRANS, &ad); 2046 if (rc) 2047 return rc; 2048 } else { 2049 /* Check permissions for the transition. */ 2050 rc = avc_has_perm(old_tsec->sid, new_tsec->sid, 2051 SECCLASS_PROCESS, PROCESS__TRANSITION, &ad); 2052 if (rc) 2053 return rc; 2054 2055 rc = avc_has_perm(new_tsec->sid, isec->sid, 2056 SECCLASS_FILE, FILE__ENTRYPOINT, &ad); 2057 if (rc) 2058 return rc; 2059 2060 /* Check for shared state */ 2061 if (bprm->unsafe & LSM_UNSAFE_SHARE) { 2062 rc = avc_has_perm(old_tsec->sid, new_tsec->sid, 2063 SECCLASS_PROCESS, PROCESS__SHARE, 2064 NULL); 2065 if (rc) 2066 return -EPERM; 2067 } 2068 2069 /* Make sure that anyone attempting to ptrace over a task that 2070 * changes its SID has the appropriate permit */ 2071 if (bprm->unsafe & 2072 (LSM_UNSAFE_PTRACE | LSM_UNSAFE_PTRACE_CAP)) { 2073 struct task_struct *tracer; 2074 struct task_security_struct *sec; 2075 u32 ptsid = 0; 2076 2077 rcu_read_lock(); 2078 tracer = ptrace_parent(current); 2079 if (likely(tracer != NULL)) { 2080 sec = __task_cred(tracer)->security; 2081 ptsid = sec->sid; 2082 } 2083 rcu_read_unlock(); 2084 2085 if (ptsid != 0) { 2086 rc = avc_has_perm(ptsid, new_tsec->sid, 2087 SECCLASS_PROCESS, 2088 PROCESS__PTRACE, NULL); 2089 if (rc) 2090 return -EPERM; 2091 } 2092 } 2093 2094 /* Clear any possibly unsafe personality bits on exec: */ 2095 bprm->per_clear |= PER_CLEAR_ON_SETID; 2096 } 2097 2098 return 0; 2099 } 2100 2101 static int selinux_bprm_secureexec(struct linux_binprm *bprm) 2102 { 2103 const struct task_security_struct *tsec = current_security(); 2104 u32 sid, osid; 2105 int atsecure = 0; 2106 2107 sid = tsec->sid; 2108 osid = tsec->osid; 2109 2110 if (osid != sid) { 2111 /* Enable secure mode for SIDs transitions unless 2112 the noatsecure permission is granted between 2113 the two SIDs, i.e. ahp returns 0. */ 2114 atsecure = avc_has_perm(osid, sid, 2115 SECCLASS_PROCESS, 2116 PROCESS__NOATSECURE, NULL); 2117 } 2118 2119 return (atsecure || cap_bprm_secureexec(bprm)); 2120 } 2121 2122 /* Derived from fs/exec.c:flush_old_files. */ 2123 static inline void flush_unauthorized_files(const struct cred *cred, 2124 struct files_struct *files) 2125 { 2126 struct common_audit_data ad; 2127 struct selinux_audit_data sad = {0,}; 2128 struct file *file, *devnull = NULL; 2129 struct tty_struct *tty; 2130 struct fdtable *fdt; 2131 long j = -1; 2132 int drop_tty = 0; 2133 2134 tty = get_current_tty(); 2135 if (tty) { 2136 spin_lock(&tty_files_lock); 2137 if (!list_empty(&tty->tty_files)) { 2138 struct tty_file_private *file_priv; 2139 struct inode *inode; 2140 2141 /* Revalidate access to controlling tty. 2142 Use inode_has_perm on the tty inode directly rather 2143 than using file_has_perm, as this particular open 2144 file may belong to another process and we are only 2145 interested in the inode-based check here. */ 2146 file_priv = list_first_entry(&tty->tty_files, 2147 struct tty_file_private, list); 2148 file = file_priv->file; 2149 inode = file->f_path.dentry->d_inode; 2150 if (inode_has_perm_noadp(cred, inode, 2151 FILE__READ | FILE__WRITE, 0)) { 2152 drop_tty = 1; 2153 } 2154 } 2155 spin_unlock(&tty_files_lock); 2156 tty_kref_put(tty); 2157 } 2158 /* Reset controlling tty. */ 2159 if (drop_tty) 2160 no_tty(); 2161 2162 /* Revalidate access to inherited open files. */ 2163 2164 COMMON_AUDIT_DATA_INIT(&ad, INODE); 2165 ad.selinux_audit_data = &sad; 2166 2167 spin_lock(&files->file_lock); 2168 for (;;) { 2169 unsigned long set, i; 2170 int fd; 2171 2172 j++; 2173 i = j * __NFDBITS; 2174 fdt = files_fdtable(files); 2175 if (i >= fdt->max_fds) 2176 break; 2177 set = fdt->open_fds[j]; 2178 if (!set) 2179 continue; 2180 spin_unlock(&files->file_lock); 2181 for ( ; set ; i++, set >>= 1) { 2182 if (set & 1) { 2183 file = fget(i); 2184 if (!file) 2185 continue; 2186 if (file_has_perm(cred, 2187 file, 2188 file_to_av(file))) { 2189 sys_close(i); 2190 fd = get_unused_fd(); 2191 if (fd != i) { 2192 if (fd >= 0) 2193 put_unused_fd(fd); 2194 fput(file); 2195 continue; 2196 } 2197 if (devnull) { 2198 get_file(devnull); 2199 } else { 2200 devnull = dentry_open( 2201 dget(selinux_null), 2202 mntget(selinuxfs_mount), 2203 O_RDWR, cred); 2204 if (IS_ERR(devnull)) { 2205 devnull = NULL; 2206 put_unused_fd(fd); 2207 fput(file); 2208 continue; 2209 } 2210 } 2211 fd_install(fd, devnull); 2212 } 2213 fput(file); 2214 } 2215 } 2216 spin_lock(&files->file_lock); 2217 2218 } 2219 spin_unlock(&files->file_lock); 2220 } 2221 2222 /* 2223 * Prepare a process for imminent new credential changes due to exec 2224 */ 2225 static void selinux_bprm_committing_creds(struct linux_binprm *bprm) 2226 { 2227 struct task_security_struct *new_tsec; 2228 struct rlimit *rlim, *initrlim; 2229 int rc, i; 2230 2231 new_tsec = bprm->cred->security; 2232 if (new_tsec->sid == new_tsec->osid) 2233 return; 2234 2235 /* Close files for which the new task SID is not authorized. */ 2236 flush_unauthorized_files(bprm->cred, current->files); 2237 2238 /* Always clear parent death signal on SID transitions. */ 2239 current->pdeath_signal = 0; 2240 2241 /* Check whether the new SID can inherit resource limits from the old 2242 * SID. If not, reset all soft limits to the lower of the current 2243 * task's hard limit and the init task's soft limit. 2244 * 2245 * Note that the setting of hard limits (even to lower them) can be 2246 * controlled by the setrlimit check. The inclusion of the init task's 2247 * soft limit into the computation is to avoid resetting soft limits 2248 * higher than the default soft limit for cases where the default is 2249 * lower than the hard limit, e.g. RLIMIT_CORE or RLIMIT_STACK. 2250 */ 2251 rc = avc_has_perm(new_tsec->osid, new_tsec->sid, SECCLASS_PROCESS, 2252 PROCESS__RLIMITINH, NULL); 2253 if (rc) { 2254 /* protect against do_prlimit() */ 2255 task_lock(current); 2256 for (i = 0; i < RLIM_NLIMITS; i++) { 2257 rlim = current->signal->rlim + i; 2258 initrlim = init_task.signal->rlim + i; 2259 rlim->rlim_cur = min(rlim->rlim_max, initrlim->rlim_cur); 2260 } 2261 task_unlock(current); 2262 update_rlimit_cpu(current, rlimit(RLIMIT_CPU)); 2263 } 2264 } 2265 2266 /* 2267 * Clean up the process immediately after the installation of new credentials 2268 * due to exec 2269 */ 2270 static void selinux_bprm_committed_creds(struct linux_binprm *bprm) 2271 { 2272 const struct task_security_struct *tsec = current_security(); 2273 struct itimerval itimer; 2274 u32 osid, sid; 2275 int rc, i; 2276 2277 osid = tsec->osid; 2278 sid = tsec->sid; 2279 2280 if (sid == osid) 2281 return; 2282 2283 /* Check whether the new SID can inherit signal state from the old SID. 2284 * If not, clear itimers to avoid subsequent signal generation and 2285 * flush and unblock signals. 2286 * 2287 * This must occur _after_ the task SID has been updated so that any 2288 * kill done after the flush will be checked against the new SID. 2289 */ 2290 rc = avc_has_perm(osid, sid, SECCLASS_PROCESS, PROCESS__SIGINH, NULL); 2291 if (rc) { 2292 memset(&itimer, 0, sizeof itimer); 2293 for (i = 0; i < 3; i++) 2294 do_setitimer(i, &itimer, NULL); 2295 spin_lock_irq(¤t->sighand->siglock); 2296 if (!(current->signal->flags & SIGNAL_GROUP_EXIT)) { 2297 __flush_signals(current); 2298 flush_signal_handlers(current, 1); 2299 sigemptyset(¤t->blocked); 2300 } 2301 spin_unlock_irq(¤t->sighand->siglock); 2302 } 2303 2304 /* Wake up the parent if it is waiting so that it can recheck 2305 * wait permission to the new task SID. */ 2306 read_lock(&tasklist_lock); 2307 __wake_up_parent(current, current->real_parent); 2308 read_unlock(&tasklist_lock); 2309 } 2310 2311 /* superblock security operations */ 2312 2313 static int selinux_sb_alloc_security(struct super_block *sb) 2314 { 2315 return superblock_alloc_security(sb); 2316 } 2317 2318 static void selinux_sb_free_security(struct super_block *sb) 2319 { 2320 superblock_free_security(sb); 2321 } 2322 2323 static inline int match_prefix(char *prefix, int plen, char *option, int olen) 2324 { 2325 if (plen > olen) 2326 return 0; 2327 2328 return !memcmp(prefix, option, plen); 2329 } 2330 2331 static inline int selinux_option(char *option, int len) 2332 { 2333 return (match_prefix(CONTEXT_STR, sizeof(CONTEXT_STR)-1, option, len) || 2334 match_prefix(FSCONTEXT_STR, sizeof(FSCONTEXT_STR)-1, option, len) || 2335 match_prefix(DEFCONTEXT_STR, sizeof(DEFCONTEXT_STR)-1, option, len) || 2336 match_prefix(ROOTCONTEXT_STR, sizeof(ROOTCONTEXT_STR)-1, option, len) || 2337 match_prefix(LABELSUPP_STR, sizeof(LABELSUPP_STR)-1, option, len)); 2338 } 2339 2340 static inline void take_option(char **to, char *from, int *first, int len) 2341 { 2342 if (!*first) { 2343 **to = ','; 2344 *to += 1; 2345 } else 2346 *first = 0; 2347 memcpy(*to, from, len); 2348 *to += len; 2349 } 2350 2351 static inline void take_selinux_option(char **to, char *from, int *first, 2352 int len) 2353 { 2354 int current_size = 0; 2355 2356 if (!*first) { 2357 **to = '|'; 2358 *to += 1; 2359 } else 2360 *first = 0; 2361 2362 while (current_size < len) { 2363 if (*from != '"') { 2364 **to = *from; 2365 *to += 1; 2366 } 2367 from += 1; 2368 current_size += 1; 2369 } 2370 } 2371 2372 static int selinux_sb_copy_data(char *orig, char *copy) 2373 { 2374 int fnosec, fsec, rc = 0; 2375 char *in_save, *in_curr, *in_end; 2376 char *sec_curr, *nosec_save, *nosec; 2377 int open_quote = 0; 2378 2379 in_curr = orig; 2380 sec_curr = copy; 2381 2382 nosec = (char *)get_zeroed_page(GFP_KERNEL); 2383 if (!nosec) { 2384 rc = -ENOMEM; 2385 goto out; 2386 } 2387 2388 nosec_save = nosec; 2389 fnosec = fsec = 1; 2390 in_save = in_end = orig; 2391 2392 do { 2393 if (*in_end == '"') 2394 open_quote = !open_quote; 2395 if ((*in_end == ',' && open_quote == 0) || 2396 *in_end == '\0') { 2397 int len = in_end - in_curr; 2398 2399 if (selinux_option(in_curr, len)) 2400 take_selinux_option(&sec_curr, in_curr, &fsec, len); 2401 else 2402 take_option(&nosec, in_curr, &fnosec, len); 2403 2404 in_curr = in_end + 1; 2405 } 2406 } while (*in_end++); 2407 2408 strcpy(in_save, nosec_save); 2409 free_page((unsigned long)nosec_save); 2410 out: 2411 return rc; 2412 } 2413 2414 static int selinux_sb_remount(struct super_block *sb, void *data) 2415 { 2416 int rc, i, *flags; 2417 struct security_mnt_opts opts; 2418 char *secdata, **mount_options; 2419 struct superblock_security_struct *sbsec = sb->s_security; 2420 2421 if (!(sbsec->flags & SE_SBINITIALIZED)) 2422 return 0; 2423 2424 if (!data) 2425 return 0; 2426 2427 if (sb->s_type->fs_flags & FS_BINARY_MOUNTDATA) 2428 return 0; 2429 2430 security_init_mnt_opts(&opts); 2431 secdata = alloc_secdata(); 2432 if (!secdata) 2433 return -ENOMEM; 2434 rc = selinux_sb_copy_data(data, secdata); 2435 if (rc) 2436 goto out_free_secdata; 2437 2438 rc = selinux_parse_opts_str(secdata, &opts); 2439 if (rc) 2440 goto out_free_secdata; 2441 2442 mount_options = opts.mnt_opts; 2443 flags = opts.mnt_opts_flags; 2444 2445 for (i = 0; i < opts.num_mnt_opts; i++) { 2446 u32 sid; 2447 size_t len; 2448 2449 if (flags[i] == SE_SBLABELSUPP) 2450 continue; 2451 len = strlen(mount_options[i]); 2452 rc = security_context_to_sid(mount_options[i], len, &sid); 2453 if (rc) { 2454 printk(KERN_WARNING "SELinux: security_context_to_sid" 2455 "(%s) failed for (dev %s, type %s) errno=%d\n", 2456 mount_options[i], sb->s_id, sb->s_type->name, rc); 2457 goto out_free_opts; 2458 } 2459 rc = -EINVAL; 2460 switch (flags[i]) { 2461 case FSCONTEXT_MNT: 2462 if (bad_option(sbsec, FSCONTEXT_MNT, sbsec->sid, sid)) 2463 goto out_bad_option; 2464 break; 2465 case CONTEXT_MNT: 2466 if (bad_option(sbsec, CONTEXT_MNT, sbsec->mntpoint_sid, sid)) 2467 goto out_bad_option; 2468 break; 2469 case ROOTCONTEXT_MNT: { 2470 struct inode_security_struct *root_isec; 2471 root_isec = sb->s_root->d_inode->i_security; 2472 2473 if (bad_option(sbsec, ROOTCONTEXT_MNT, root_isec->sid, sid)) 2474 goto out_bad_option; 2475 break; 2476 } 2477 case DEFCONTEXT_MNT: 2478 if (bad_option(sbsec, DEFCONTEXT_MNT, sbsec->def_sid, sid)) 2479 goto out_bad_option; 2480 break; 2481 default: 2482 goto out_free_opts; 2483 } 2484 } 2485 2486 rc = 0; 2487 out_free_opts: 2488 security_free_mnt_opts(&opts); 2489 out_free_secdata: 2490 free_secdata(secdata); 2491 return rc; 2492 out_bad_option: 2493 printk(KERN_WARNING "SELinux: unable to change security options " 2494 "during remount (dev %s, type=%s)\n", sb->s_id, 2495 sb->s_type->name); 2496 goto out_free_opts; 2497 } 2498 2499 static int selinux_sb_kern_mount(struct super_block *sb, int flags, void *data) 2500 { 2501 const struct cred *cred = current_cred(); 2502 struct common_audit_data ad; 2503 struct selinux_audit_data sad = {0,}; 2504 int rc; 2505 2506 rc = superblock_doinit(sb, data); 2507 if (rc) 2508 return rc; 2509 2510 /* Allow all mounts performed by the kernel */ 2511 if (flags & MS_KERNMOUNT) 2512 return 0; 2513 2514 COMMON_AUDIT_DATA_INIT(&ad, DENTRY); 2515 ad.selinux_audit_data = &sad; 2516 ad.u.dentry = sb->s_root; 2517 return superblock_has_perm(cred, sb, FILESYSTEM__MOUNT, &ad); 2518 } 2519 2520 static int selinux_sb_statfs(struct dentry *dentry) 2521 { 2522 const struct cred *cred = current_cred(); 2523 struct common_audit_data ad; 2524 struct selinux_audit_data sad = {0,}; 2525 2526 COMMON_AUDIT_DATA_INIT(&ad, DENTRY); 2527 ad.selinux_audit_data = &sad; 2528 ad.u.dentry = dentry->d_sb->s_root; 2529 return superblock_has_perm(cred, dentry->d_sb, FILESYSTEM__GETATTR, &ad); 2530 } 2531 2532 static int selinux_mount(char *dev_name, 2533 struct path *path, 2534 char *type, 2535 unsigned long flags, 2536 void *data) 2537 { 2538 const struct cred *cred = current_cred(); 2539 2540 if (flags & MS_REMOUNT) 2541 return superblock_has_perm(cred, path->dentry->d_sb, 2542 FILESYSTEM__REMOUNT, NULL); 2543 else 2544 return path_has_perm(cred, path, FILE__MOUNTON); 2545 } 2546 2547 static int selinux_umount(struct vfsmount *mnt, int flags) 2548 { 2549 const struct cred *cred = current_cred(); 2550 2551 return superblock_has_perm(cred, mnt->mnt_sb, 2552 FILESYSTEM__UNMOUNT, NULL); 2553 } 2554 2555 /* inode security operations */ 2556 2557 static int selinux_inode_alloc_security(struct inode *inode) 2558 { 2559 return inode_alloc_security(inode); 2560 } 2561 2562 static void selinux_inode_free_security(struct inode *inode) 2563 { 2564 inode_free_security(inode); 2565 } 2566 2567 static int selinux_inode_init_security(struct inode *inode, struct inode *dir, 2568 const struct qstr *qstr, char **name, 2569 void **value, size_t *len) 2570 { 2571 const struct task_security_struct *tsec = current_security(); 2572 struct inode_security_struct *dsec; 2573 struct superblock_security_struct *sbsec; 2574 u32 sid, newsid, clen; 2575 int rc; 2576 char *namep = NULL, *context; 2577 2578 dsec = dir->i_security; 2579 sbsec = dir->i_sb->s_security; 2580 2581 sid = tsec->sid; 2582 newsid = tsec->create_sid; 2583 2584 if ((sbsec->flags & SE_SBINITIALIZED) && 2585 (sbsec->behavior == SECURITY_FS_USE_MNTPOINT)) 2586 newsid = sbsec->mntpoint_sid; 2587 else if (!newsid || !(sbsec->flags & SE_SBLABELSUPP)) { 2588 rc = security_transition_sid(sid, dsec->sid, 2589 inode_mode_to_security_class(inode->i_mode), 2590 qstr, &newsid); 2591 if (rc) { 2592 printk(KERN_WARNING "%s: " 2593 "security_transition_sid failed, rc=%d (dev=%s " 2594 "ino=%ld)\n", 2595 __func__, 2596 -rc, inode->i_sb->s_id, inode->i_ino); 2597 return rc; 2598 } 2599 } 2600 2601 /* Possibly defer initialization to selinux_complete_init. */ 2602 if (sbsec->flags & SE_SBINITIALIZED) { 2603 struct inode_security_struct *isec = inode->i_security; 2604 isec->sclass = inode_mode_to_security_class(inode->i_mode); 2605 isec->sid = newsid; 2606 isec->initialized = 1; 2607 } 2608 2609 if (!ss_initialized || !(sbsec->flags & SE_SBLABELSUPP)) 2610 return -EOPNOTSUPP; 2611 2612 if (name) { 2613 namep = kstrdup(XATTR_SELINUX_SUFFIX, GFP_NOFS); 2614 if (!namep) 2615 return -ENOMEM; 2616 *name = namep; 2617 } 2618 2619 if (value && len) { 2620 rc = security_sid_to_context_force(newsid, &context, &clen); 2621 if (rc) { 2622 kfree(namep); 2623 return rc; 2624 } 2625 *value = context; 2626 *len = clen; 2627 } 2628 2629 return 0; 2630 } 2631 2632 static int selinux_inode_create(struct inode *dir, struct dentry *dentry, umode_t mode) 2633 { 2634 return may_create(dir, dentry, SECCLASS_FILE); 2635 } 2636 2637 static int selinux_inode_link(struct dentry *old_dentry, struct inode *dir, struct dentry *new_dentry) 2638 { 2639 return may_link(dir, old_dentry, MAY_LINK); 2640 } 2641 2642 static int selinux_inode_unlink(struct inode *dir, struct dentry *dentry) 2643 { 2644 return may_link(dir, dentry, MAY_UNLINK); 2645 } 2646 2647 static int selinux_inode_symlink(struct inode *dir, struct dentry *dentry, const char *name) 2648 { 2649 return may_create(dir, dentry, SECCLASS_LNK_FILE); 2650 } 2651 2652 static int selinux_inode_mkdir(struct inode *dir, struct dentry *dentry, umode_t mask) 2653 { 2654 return may_create(dir, dentry, SECCLASS_DIR); 2655 } 2656 2657 static int selinux_inode_rmdir(struct inode *dir, struct dentry *dentry) 2658 { 2659 return may_link(dir, dentry, MAY_RMDIR); 2660 } 2661 2662 static int selinux_inode_mknod(struct inode *dir, struct dentry *dentry, umode_t mode, dev_t dev) 2663 { 2664 return may_create(dir, dentry, inode_mode_to_security_class(mode)); 2665 } 2666 2667 static int selinux_inode_rename(struct inode *old_inode, struct dentry *old_dentry, 2668 struct inode *new_inode, struct dentry *new_dentry) 2669 { 2670 return may_rename(old_inode, old_dentry, new_inode, new_dentry); 2671 } 2672 2673 static int selinux_inode_readlink(struct dentry *dentry) 2674 { 2675 const struct cred *cred = current_cred(); 2676 2677 return dentry_has_perm(cred, dentry, FILE__READ); 2678 } 2679 2680 static int selinux_inode_follow_link(struct dentry *dentry, struct nameidata *nameidata) 2681 { 2682 const struct cred *cred = current_cred(); 2683 2684 return dentry_has_perm(cred, dentry, FILE__READ); 2685 } 2686 2687 static int selinux_inode_permission(struct inode *inode, int mask) 2688 { 2689 const struct cred *cred = current_cred(); 2690 struct common_audit_data ad; 2691 struct selinux_audit_data sad = {0,}; 2692 u32 perms; 2693 bool from_access; 2694 unsigned flags = mask & MAY_NOT_BLOCK; 2695 2696 from_access = mask & MAY_ACCESS; 2697 mask &= (MAY_READ|MAY_WRITE|MAY_EXEC|MAY_APPEND); 2698 2699 /* No permission to check. Existence test. */ 2700 if (!mask) 2701 return 0; 2702 2703 COMMON_AUDIT_DATA_INIT(&ad, INODE); 2704 ad.selinux_audit_data = &sad; 2705 ad.u.inode = inode; 2706 2707 if (from_access) 2708 ad.selinux_audit_data->auditdeny |= FILE__AUDIT_ACCESS; 2709 2710 perms = file_mask_to_av(inode->i_mode, mask); 2711 2712 return inode_has_perm(cred, inode, perms, &ad, flags); 2713 } 2714 2715 static int selinux_inode_setattr(struct dentry *dentry, struct iattr *iattr) 2716 { 2717 const struct cred *cred = current_cred(); 2718 unsigned int ia_valid = iattr->ia_valid; 2719 2720 /* ATTR_FORCE is just used for ATTR_KILL_S[UG]ID. */ 2721 if (ia_valid & ATTR_FORCE) { 2722 ia_valid &= ~(ATTR_KILL_SUID | ATTR_KILL_SGID | ATTR_MODE | 2723 ATTR_FORCE); 2724 if (!ia_valid) 2725 return 0; 2726 } 2727 2728 if (ia_valid & (ATTR_MODE | ATTR_UID | ATTR_GID | 2729 ATTR_ATIME_SET | ATTR_MTIME_SET | ATTR_TIMES_SET)) 2730 return dentry_has_perm(cred, dentry, FILE__SETATTR); 2731 2732 return dentry_has_perm(cred, dentry, FILE__WRITE); 2733 } 2734 2735 static int selinux_inode_getattr(struct vfsmount *mnt, struct dentry *dentry) 2736 { 2737 const struct cred *cred = current_cred(); 2738 struct path path; 2739 2740 path.dentry = dentry; 2741 path.mnt = mnt; 2742 2743 return path_has_perm(cred, &path, FILE__GETATTR); 2744 } 2745 2746 static int selinux_inode_setotherxattr(struct dentry *dentry, const char *name) 2747 { 2748 const struct cred *cred = current_cred(); 2749 2750 if (!strncmp(name, XATTR_SECURITY_PREFIX, 2751 sizeof XATTR_SECURITY_PREFIX - 1)) { 2752 if (!strcmp(name, XATTR_NAME_CAPS)) { 2753 if (!capable(CAP_SETFCAP)) 2754 return -EPERM; 2755 } else if (!capable(CAP_SYS_ADMIN)) { 2756 /* A different attribute in the security namespace. 2757 Restrict to administrator. */ 2758 return -EPERM; 2759 } 2760 } 2761 2762 /* Not an attribute we recognize, so just check the 2763 ordinary setattr permission. */ 2764 return dentry_has_perm(cred, dentry, FILE__SETATTR); 2765 } 2766 2767 static int selinux_inode_setxattr(struct dentry *dentry, const char *name, 2768 const void *value, size_t size, int flags) 2769 { 2770 struct inode *inode = dentry->d_inode; 2771 struct inode_security_struct *isec = inode->i_security; 2772 struct superblock_security_struct *sbsec; 2773 struct common_audit_data ad; 2774 struct selinux_audit_data sad = {0,}; 2775 u32 newsid, sid = current_sid(); 2776 int rc = 0; 2777 2778 if (strcmp(name, XATTR_NAME_SELINUX)) 2779 return selinux_inode_setotherxattr(dentry, name); 2780 2781 sbsec = inode->i_sb->s_security; 2782 if (!(sbsec->flags & SE_SBLABELSUPP)) 2783 return -EOPNOTSUPP; 2784 2785 if (!inode_owner_or_capable(inode)) 2786 return -EPERM; 2787 2788 COMMON_AUDIT_DATA_INIT(&ad, DENTRY); 2789 ad.selinux_audit_data = &sad; 2790 ad.u.dentry = dentry; 2791 2792 rc = avc_has_perm(sid, isec->sid, isec->sclass, 2793 FILE__RELABELFROM, &ad); 2794 if (rc) 2795 return rc; 2796 2797 rc = security_context_to_sid(value, size, &newsid); 2798 if (rc == -EINVAL) { 2799 if (!capable(CAP_MAC_ADMIN)) 2800 return rc; 2801 rc = security_context_to_sid_force(value, size, &newsid); 2802 } 2803 if (rc) 2804 return rc; 2805 2806 rc = avc_has_perm(sid, newsid, isec->sclass, 2807 FILE__RELABELTO, &ad); 2808 if (rc) 2809 return rc; 2810 2811 rc = security_validate_transition(isec->sid, newsid, sid, 2812 isec->sclass); 2813 if (rc) 2814 return rc; 2815 2816 return avc_has_perm(newsid, 2817 sbsec->sid, 2818 SECCLASS_FILESYSTEM, 2819 FILESYSTEM__ASSOCIATE, 2820 &ad); 2821 } 2822 2823 static void selinux_inode_post_setxattr(struct dentry *dentry, const char *name, 2824 const void *value, size_t size, 2825 int flags) 2826 { 2827 struct inode *inode = dentry->d_inode; 2828 struct inode_security_struct *isec = inode->i_security; 2829 u32 newsid; 2830 int rc; 2831 2832 if (strcmp(name, XATTR_NAME_SELINUX)) { 2833 /* Not an attribute we recognize, so nothing to do. */ 2834 return; 2835 } 2836 2837 rc = security_context_to_sid_force(value, size, &newsid); 2838 if (rc) { 2839 printk(KERN_ERR "SELinux: unable to map context to SID" 2840 "for (%s, %lu), rc=%d\n", 2841 inode->i_sb->s_id, inode->i_ino, -rc); 2842 return; 2843 } 2844 2845 isec->sid = newsid; 2846 return; 2847 } 2848 2849 static int selinux_inode_getxattr(struct dentry *dentry, const char *name) 2850 { 2851 const struct cred *cred = current_cred(); 2852 2853 return dentry_has_perm(cred, dentry, FILE__GETATTR); 2854 } 2855 2856 static int selinux_inode_listxattr(struct dentry *dentry) 2857 { 2858 const struct cred *cred = current_cred(); 2859 2860 return dentry_has_perm(cred, dentry, FILE__GETATTR); 2861 } 2862 2863 static int selinux_inode_removexattr(struct dentry *dentry, const char *name) 2864 { 2865 if (strcmp(name, XATTR_NAME_SELINUX)) 2866 return selinux_inode_setotherxattr(dentry, name); 2867 2868 /* No one is allowed to remove a SELinux security label. 2869 You can change the label, but all data must be labeled. */ 2870 return -EACCES; 2871 } 2872 2873 /* 2874 * Copy the inode security context value to the user. 2875 * 2876 * Permission check is handled by selinux_inode_getxattr hook. 2877 */ 2878 static int selinux_inode_getsecurity(const struct inode *inode, const char *name, void **buffer, bool alloc) 2879 { 2880 u32 size; 2881 int error; 2882 char *context = NULL; 2883 struct inode_security_struct *isec = inode->i_security; 2884 2885 if (strcmp(name, XATTR_SELINUX_SUFFIX)) 2886 return -EOPNOTSUPP; 2887 2888 /* 2889 * If the caller has CAP_MAC_ADMIN, then get the raw context 2890 * value even if it is not defined by current policy; otherwise, 2891 * use the in-core value under current policy. 2892 * Use the non-auditing forms of the permission checks since 2893 * getxattr may be called by unprivileged processes commonly 2894 * and lack of permission just means that we fall back to the 2895 * in-core context value, not a denial. 2896 */ 2897 error = selinux_capable(current_cred(), &init_user_ns, CAP_MAC_ADMIN, 2898 SECURITY_CAP_NOAUDIT); 2899 if (!error) 2900 error = security_sid_to_context_force(isec->sid, &context, 2901 &size); 2902 else 2903 error = security_sid_to_context(isec->sid, &context, &size); 2904 if (error) 2905 return error; 2906 error = size; 2907 if (alloc) { 2908 *buffer = context; 2909 goto out_nofree; 2910 } 2911 kfree(context); 2912 out_nofree: 2913 return error; 2914 } 2915 2916 static int selinux_inode_setsecurity(struct inode *inode, const char *name, 2917 const void *value, size_t size, int flags) 2918 { 2919 struct inode_security_struct *isec = inode->i_security; 2920 u32 newsid; 2921 int rc; 2922 2923 if (strcmp(name, XATTR_SELINUX_SUFFIX)) 2924 return -EOPNOTSUPP; 2925 2926 if (!value || !size) 2927 return -EACCES; 2928 2929 rc = security_context_to_sid((void *)value, size, &newsid); 2930 if (rc) 2931 return rc; 2932 2933 isec->sid = newsid; 2934 isec->initialized = 1; 2935 return 0; 2936 } 2937 2938 static int selinux_inode_listsecurity(struct inode *inode, char *buffer, size_t buffer_size) 2939 { 2940 const int len = sizeof(XATTR_NAME_SELINUX); 2941 if (buffer && len <= buffer_size) 2942 memcpy(buffer, XATTR_NAME_SELINUX, len); 2943 return len; 2944 } 2945 2946 static void selinux_inode_getsecid(const struct inode *inode, u32 *secid) 2947 { 2948 struct inode_security_struct *isec = inode->i_security; 2949 *secid = isec->sid; 2950 } 2951 2952 /* file security operations */ 2953 2954 static int selinux_revalidate_file_permission(struct file *file, int mask) 2955 { 2956 const struct cred *cred = current_cred(); 2957 struct inode *inode = file->f_path.dentry->d_inode; 2958 2959 /* file_mask_to_av won't add FILE__WRITE if MAY_APPEND is set */ 2960 if ((file->f_flags & O_APPEND) && (mask & MAY_WRITE)) 2961 mask |= MAY_APPEND; 2962 2963 return file_has_perm(cred, file, 2964 file_mask_to_av(inode->i_mode, mask)); 2965 } 2966 2967 static int selinux_file_permission(struct file *file, int mask) 2968 { 2969 struct inode *inode = file->f_path.dentry->d_inode; 2970 struct file_security_struct *fsec = file->f_security; 2971 struct inode_security_struct *isec = inode->i_security; 2972 u32 sid = current_sid(); 2973 2974 if (!mask) 2975 /* No permission to check. Existence test. */ 2976 return 0; 2977 2978 if (sid == fsec->sid && fsec->isid == isec->sid && 2979 fsec->pseqno == avc_policy_seqno()) 2980 /* No change since dentry_open check. */ 2981 return 0; 2982 2983 return selinux_revalidate_file_permission(file, mask); 2984 } 2985 2986 static int selinux_file_alloc_security(struct file *file) 2987 { 2988 return file_alloc_security(file); 2989 } 2990 2991 static void selinux_file_free_security(struct file *file) 2992 { 2993 file_free_security(file); 2994 } 2995 2996 static int selinux_file_ioctl(struct file *file, unsigned int cmd, 2997 unsigned long arg) 2998 { 2999 const struct cred *cred = current_cred(); 3000 int error = 0; 3001 3002 switch (cmd) { 3003 case FIONREAD: 3004 /* fall through */ 3005 case FIBMAP: 3006 /* fall through */ 3007 case FIGETBSZ: 3008 /* fall through */ 3009 case FS_IOC_GETFLAGS: 3010 /* fall through */ 3011 case FS_IOC_GETVERSION: 3012 error = file_has_perm(cred, file, FILE__GETATTR); 3013 break; 3014 3015 case FS_IOC_SETFLAGS: 3016 /* fall through */ 3017 case FS_IOC_SETVERSION: 3018 error = file_has_perm(cred, file, FILE__SETATTR); 3019 break; 3020 3021 /* sys_ioctl() checks */ 3022 case FIONBIO: 3023 /* fall through */ 3024 case FIOASYNC: 3025 error = file_has_perm(cred, file, 0); 3026 break; 3027 3028 case KDSKBENT: 3029 case KDSKBSENT: 3030 error = cred_has_capability(cred, CAP_SYS_TTY_CONFIG, 3031 SECURITY_CAP_AUDIT); 3032 break; 3033 3034 /* default case assumes that the command will go 3035 * to the file's ioctl() function. 3036 */ 3037 default: 3038 error = file_has_perm(cred, file, FILE__IOCTL); 3039 } 3040 return error; 3041 } 3042 3043 static int default_noexec; 3044 3045 static int file_map_prot_check(struct file *file, unsigned long prot, int shared) 3046 { 3047 const struct cred *cred = current_cred(); 3048 int rc = 0; 3049 3050 if (default_noexec && 3051 (prot & PROT_EXEC) && (!file || (!shared && (prot & PROT_WRITE)))) { 3052 /* 3053 * We are making executable an anonymous mapping or a 3054 * private file mapping that will also be writable. 3055 * This has an additional check. 3056 */ 3057 rc = cred_has_perm(cred, cred, PROCESS__EXECMEM); 3058 if (rc) 3059 goto error; 3060 } 3061 3062 if (file) { 3063 /* read access is always possible with a mapping */ 3064 u32 av = FILE__READ; 3065 3066 /* write access only matters if the mapping is shared */ 3067 if (shared && (prot & PROT_WRITE)) 3068 av |= FILE__WRITE; 3069 3070 if (prot & PROT_EXEC) 3071 av |= FILE__EXECUTE; 3072 3073 return file_has_perm(cred, file, av); 3074 } 3075 3076 error: 3077 return rc; 3078 } 3079 3080 static int selinux_file_mmap(struct file *file, unsigned long reqprot, 3081 unsigned long prot, unsigned long flags, 3082 unsigned long addr, unsigned long addr_only) 3083 { 3084 int rc = 0; 3085 u32 sid = current_sid(); 3086 3087 /* 3088 * notice that we are intentionally putting the SELinux check before 3089 * the secondary cap_file_mmap check. This is such a likely attempt 3090 * at bad behaviour/exploit that we always want to get the AVC, even 3091 * if DAC would have also denied the operation. 3092 */ 3093 if (addr < CONFIG_LSM_MMAP_MIN_ADDR) { 3094 rc = avc_has_perm(sid, sid, SECCLASS_MEMPROTECT, 3095 MEMPROTECT__MMAP_ZERO, NULL); 3096 if (rc) 3097 return rc; 3098 } 3099 3100 /* do DAC check on address space usage */ 3101 rc = cap_file_mmap(file, reqprot, prot, flags, addr, addr_only); 3102 if (rc || addr_only) 3103 return rc; 3104 3105 if (selinux_checkreqprot) 3106 prot = reqprot; 3107 3108 return file_map_prot_check(file, prot, 3109 (flags & MAP_TYPE) == MAP_SHARED); 3110 } 3111 3112 static int selinux_file_mprotect(struct vm_area_struct *vma, 3113 unsigned long reqprot, 3114 unsigned long prot) 3115 { 3116 const struct cred *cred = current_cred(); 3117 3118 if (selinux_checkreqprot) 3119 prot = reqprot; 3120 3121 if (default_noexec && 3122 (prot & PROT_EXEC) && !(vma->vm_flags & VM_EXEC)) { 3123 int rc = 0; 3124 if (vma->vm_start >= vma->vm_mm->start_brk && 3125 vma->vm_end <= vma->vm_mm->brk) { 3126 rc = cred_has_perm(cred, cred, PROCESS__EXECHEAP); 3127 } else if (!vma->vm_file && 3128 vma->vm_start <= vma->vm_mm->start_stack && 3129 vma->vm_end >= vma->vm_mm->start_stack) { 3130 rc = current_has_perm(current, PROCESS__EXECSTACK); 3131 } else if (vma->vm_file && vma->anon_vma) { 3132 /* 3133 * We are making executable a file mapping that has 3134 * had some COW done. Since pages might have been 3135 * written, check ability to execute the possibly 3136 * modified content. This typically should only 3137 * occur for text relocations. 3138 */ 3139 rc = file_has_perm(cred, vma->vm_file, FILE__EXECMOD); 3140 } 3141 if (rc) 3142 return rc; 3143 } 3144 3145 return file_map_prot_check(vma->vm_file, prot, vma->vm_flags&VM_SHARED); 3146 } 3147 3148 static int selinux_file_lock(struct file *file, unsigned int cmd) 3149 { 3150 const struct cred *cred = current_cred(); 3151 3152 return file_has_perm(cred, file, FILE__LOCK); 3153 } 3154 3155 static int selinux_file_fcntl(struct file *file, unsigned int cmd, 3156 unsigned long arg) 3157 { 3158 const struct cred *cred = current_cred(); 3159 int err = 0; 3160 3161 switch (cmd) { 3162 case F_SETFL: 3163 if (!file->f_path.dentry || !file->f_path.dentry->d_inode) { 3164 err = -EINVAL; 3165 break; 3166 } 3167 3168 if ((file->f_flags & O_APPEND) && !(arg & O_APPEND)) { 3169 err = file_has_perm(cred, file, FILE__WRITE); 3170 break; 3171 } 3172 /* fall through */ 3173 case F_SETOWN: 3174 case F_SETSIG: 3175 case F_GETFL: 3176 case F_GETOWN: 3177 case F_GETSIG: 3178 /* Just check FD__USE permission */ 3179 err = file_has_perm(cred, file, 0); 3180 break; 3181 case F_GETLK: 3182 case F_SETLK: 3183 case F_SETLKW: 3184 #if BITS_PER_LONG == 32 3185 case F_GETLK64: 3186 case F_SETLK64: 3187 case F_SETLKW64: 3188 #endif 3189 if (!file->f_path.dentry || !file->f_path.dentry->d_inode) { 3190 err = -EINVAL; 3191 break; 3192 } 3193 err = file_has_perm(cred, file, FILE__LOCK); 3194 break; 3195 } 3196 3197 return err; 3198 } 3199 3200 static int selinux_file_set_fowner(struct file *file) 3201 { 3202 struct file_security_struct *fsec; 3203 3204 fsec = file->f_security; 3205 fsec->fown_sid = current_sid(); 3206 3207 return 0; 3208 } 3209 3210 static int selinux_file_send_sigiotask(struct task_struct *tsk, 3211 struct fown_struct *fown, int signum) 3212 { 3213 struct file *file; 3214 u32 sid = task_sid(tsk); 3215 u32 perm; 3216 struct file_security_struct *fsec; 3217 3218 /* struct fown_struct is never outside the context of a struct file */ 3219 file = container_of(fown, struct file, f_owner); 3220 3221 fsec = file->f_security; 3222 3223 if (!signum) 3224 perm = signal_to_av(SIGIO); /* as per send_sigio_to_task */ 3225 else 3226 perm = signal_to_av(signum); 3227 3228 return avc_has_perm(fsec->fown_sid, sid, 3229 SECCLASS_PROCESS, perm, NULL); 3230 } 3231 3232 static int selinux_file_receive(struct file *file) 3233 { 3234 const struct cred *cred = current_cred(); 3235 3236 return file_has_perm(cred, file, file_to_av(file)); 3237 } 3238 3239 static int selinux_dentry_open(struct file *file, const struct cred *cred) 3240 { 3241 struct file_security_struct *fsec; 3242 struct inode *inode; 3243 struct inode_security_struct *isec; 3244 3245 inode = file->f_path.dentry->d_inode; 3246 fsec = file->f_security; 3247 isec = inode->i_security; 3248 /* 3249 * Save inode label and policy sequence number 3250 * at open-time so that selinux_file_permission 3251 * can determine whether revalidation is necessary. 3252 * Task label is already saved in the file security 3253 * struct as its SID. 3254 */ 3255 fsec->isid = isec->sid; 3256 fsec->pseqno = avc_policy_seqno(); 3257 /* 3258 * Since the inode label or policy seqno may have changed 3259 * between the selinux_inode_permission check and the saving 3260 * of state above, recheck that access is still permitted. 3261 * Otherwise, access might never be revalidated against the 3262 * new inode label or new policy. 3263 * This check is not redundant - do not remove. 3264 */ 3265 return inode_has_perm_noadp(cred, inode, open_file_to_av(file), 0); 3266 } 3267 3268 /* task security operations */ 3269 3270 static int selinux_task_create(unsigned long clone_flags) 3271 { 3272 return current_has_perm(current, PROCESS__FORK); 3273 } 3274 3275 /* 3276 * allocate the SELinux part of blank credentials 3277 */ 3278 static int selinux_cred_alloc_blank(struct cred *cred, gfp_t gfp) 3279 { 3280 struct task_security_struct *tsec; 3281 3282 tsec = kzalloc(sizeof(struct task_security_struct), gfp); 3283 if (!tsec) 3284 return -ENOMEM; 3285 3286 cred->security = tsec; 3287 return 0; 3288 } 3289 3290 /* 3291 * detach and free the LSM part of a set of credentials 3292 */ 3293 static void selinux_cred_free(struct cred *cred) 3294 { 3295 struct task_security_struct *tsec = cred->security; 3296 3297 /* 3298 * cred->security == NULL if security_cred_alloc_blank() or 3299 * security_prepare_creds() returned an error. 3300 */ 3301 BUG_ON(cred->security && (unsigned long) cred->security < PAGE_SIZE); 3302 cred->security = (void *) 0x7UL; 3303 kfree(tsec); 3304 } 3305 3306 /* 3307 * prepare a new set of credentials for modification 3308 */ 3309 static int selinux_cred_prepare(struct cred *new, const struct cred *old, 3310 gfp_t gfp) 3311 { 3312 const struct task_security_struct *old_tsec; 3313 struct task_security_struct *tsec; 3314 3315 old_tsec = old->security; 3316 3317 tsec = kmemdup(old_tsec, sizeof(struct task_security_struct), gfp); 3318 if (!tsec) 3319 return -ENOMEM; 3320 3321 new->security = tsec; 3322 return 0; 3323 } 3324 3325 /* 3326 * transfer the SELinux data to a blank set of creds 3327 */ 3328 static void selinux_cred_transfer(struct cred *new, const struct cred *old) 3329 { 3330 const struct task_security_struct *old_tsec = old->security; 3331 struct task_security_struct *tsec = new->security; 3332 3333 *tsec = *old_tsec; 3334 } 3335 3336 /* 3337 * set the security data for a kernel service 3338 * - all the creation contexts are set to unlabelled 3339 */ 3340 static int selinux_kernel_act_as(struct cred *new, u32 secid) 3341 { 3342 struct task_security_struct *tsec = new->security; 3343 u32 sid = current_sid(); 3344 int ret; 3345 3346 ret = avc_has_perm(sid, secid, 3347 SECCLASS_KERNEL_SERVICE, 3348 KERNEL_SERVICE__USE_AS_OVERRIDE, 3349 NULL); 3350 if (ret == 0) { 3351 tsec->sid = secid; 3352 tsec->create_sid = 0; 3353 tsec->keycreate_sid = 0; 3354 tsec->sockcreate_sid = 0; 3355 } 3356 return ret; 3357 } 3358 3359 /* 3360 * set the file creation context in a security record to the same as the 3361 * objective context of the specified inode 3362 */ 3363 static int selinux_kernel_create_files_as(struct cred *new, struct inode *inode) 3364 { 3365 struct inode_security_struct *isec = inode->i_security; 3366 struct task_security_struct *tsec = new->security; 3367 u32 sid = current_sid(); 3368 int ret; 3369 3370 ret = avc_has_perm(sid, isec->sid, 3371 SECCLASS_KERNEL_SERVICE, 3372 KERNEL_SERVICE__CREATE_FILES_AS, 3373 NULL); 3374 3375 if (ret == 0) 3376 tsec->create_sid = isec->sid; 3377 return ret; 3378 } 3379 3380 static int selinux_kernel_module_request(char *kmod_name) 3381 { 3382 u32 sid; 3383 struct common_audit_data ad; 3384 struct selinux_audit_data sad = {0,}; 3385 3386 sid = task_sid(current); 3387 3388 COMMON_AUDIT_DATA_INIT(&ad, KMOD); 3389 ad.selinux_audit_data = &sad; 3390 ad.u.kmod_name = kmod_name; 3391 3392 return avc_has_perm(sid, SECINITSID_KERNEL, SECCLASS_SYSTEM, 3393 SYSTEM__MODULE_REQUEST, &ad); 3394 } 3395 3396 static int selinux_task_setpgid(struct task_struct *p, pid_t pgid) 3397 { 3398 return current_has_perm(p, PROCESS__SETPGID); 3399 } 3400 3401 static int selinux_task_getpgid(struct task_struct *p) 3402 { 3403 return current_has_perm(p, PROCESS__GETPGID); 3404 } 3405 3406 static int selinux_task_getsid(struct task_struct *p) 3407 { 3408 return current_has_perm(p, PROCESS__GETSESSION); 3409 } 3410 3411 static void selinux_task_getsecid(struct task_struct *p, u32 *secid) 3412 { 3413 *secid = task_sid(p); 3414 } 3415 3416 static int selinux_task_setnice(struct task_struct *p, int nice) 3417 { 3418 int rc; 3419 3420 rc = cap_task_setnice(p, nice); 3421 if (rc) 3422 return rc; 3423 3424 return current_has_perm(p, PROCESS__SETSCHED); 3425 } 3426 3427 static int selinux_task_setioprio(struct task_struct *p, int ioprio) 3428 { 3429 int rc; 3430 3431 rc = cap_task_setioprio(p, ioprio); 3432 if (rc) 3433 return rc; 3434 3435 return current_has_perm(p, PROCESS__SETSCHED); 3436 } 3437 3438 static int selinux_task_getioprio(struct task_struct *p) 3439 { 3440 return current_has_perm(p, PROCESS__GETSCHED); 3441 } 3442 3443 static int selinux_task_setrlimit(struct task_struct *p, unsigned int resource, 3444 struct rlimit *new_rlim) 3445 { 3446 struct rlimit *old_rlim = p->signal->rlim + resource; 3447 3448 /* Control the ability to change the hard limit (whether 3449 lowering or raising it), so that the hard limit can 3450 later be used as a safe reset point for the soft limit 3451 upon context transitions. See selinux_bprm_committing_creds. */ 3452 if (old_rlim->rlim_max != new_rlim->rlim_max) 3453 return current_has_perm(p, PROCESS__SETRLIMIT); 3454 3455 return 0; 3456 } 3457 3458 static int selinux_task_setscheduler(struct task_struct *p) 3459 { 3460 int rc; 3461 3462 rc = cap_task_setscheduler(p); 3463 if (rc) 3464 return rc; 3465 3466 return current_has_perm(p, PROCESS__SETSCHED); 3467 } 3468 3469 static int selinux_task_getscheduler(struct task_struct *p) 3470 { 3471 return current_has_perm(p, PROCESS__GETSCHED); 3472 } 3473 3474 static int selinux_task_movememory(struct task_struct *p) 3475 { 3476 return current_has_perm(p, PROCESS__SETSCHED); 3477 } 3478 3479 static int selinux_task_kill(struct task_struct *p, struct siginfo *info, 3480 int sig, u32 secid) 3481 { 3482 u32 perm; 3483 int rc; 3484 3485 if (!sig) 3486 perm = PROCESS__SIGNULL; /* null signal; existence test */ 3487 else 3488 perm = signal_to_av(sig); 3489 if (secid) 3490 rc = avc_has_perm(secid, task_sid(p), 3491 SECCLASS_PROCESS, perm, NULL); 3492 else 3493 rc = current_has_perm(p, perm); 3494 return rc; 3495 } 3496 3497 static int selinux_task_wait(struct task_struct *p) 3498 { 3499 return task_has_perm(p, current, PROCESS__SIGCHLD); 3500 } 3501 3502 static void selinux_task_to_inode(struct task_struct *p, 3503 struct inode *inode) 3504 { 3505 struct inode_security_struct *isec = inode->i_security; 3506 u32 sid = task_sid(p); 3507 3508 isec->sid = sid; 3509 isec->initialized = 1; 3510 } 3511 3512 /* Returns error only if unable to parse addresses */ 3513 static int selinux_parse_skb_ipv4(struct sk_buff *skb, 3514 struct common_audit_data *ad, u8 *proto) 3515 { 3516 int offset, ihlen, ret = -EINVAL; 3517 struct iphdr _iph, *ih; 3518 3519 offset = skb_network_offset(skb); 3520 ih = skb_header_pointer(skb, offset, sizeof(_iph), &_iph); 3521 if (ih == NULL) 3522 goto out; 3523 3524 ihlen = ih->ihl * 4; 3525 if (ihlen < sizeof(_iph)) 3526 goto out; 3527 3528 ad->u.net->v4info.saddr = ih->saddr; 3529 ad->u.net->v4info.daddr = ih->daddr; 3530 ret = 0; 3531 3532 if (proto) 3533 *proto = ih->protocol; 3534 3535 switch (ih->protocol) { 3536 case IPPROTO_TCP: { 3537 struct tcphdr _tcph, *th; 3538 3539 if (ntohs(ih->frag_off) & IP_OFFSET) 3540 break; 3541 3542 offset += ihlen; 3543 th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph); 3544 if (th == NULL) 3545 break; 3546 3547 ad->u.net->sport = th->source; 3548 ad->u.net->dport = th->dest; 3549 break; 3550 } 3551 3552 case IPPROTO_UDP: { 3553 struct udphdr _udph, *uh; 3554 3555 if (ntohs(ih->frag_off) & IP_OFFSET) 3556 break; 3557 3558 offset += ihlen; 3559 uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph); 3560 if (uh == NULL) 3561 break; 3562 3563 ad->u.net->sport = uh->source; 3564 ad->u.net->dport = uh->dest; 3565 break; 3566 } 3567 3568 case IPPROTO_DCCP: { 3569 struct dccp_hdr _dccph, *dh; 3570 3571 if (ntohs(ih->frag_off) & IP_OFFSET) 3572 break; 3573 3574 offset += ihlen; 3575 dh = skb_header_pointer(skb, offset, sizeof(_dccph), &_dccph); 3576 if (dh == NULL) 3577 break; 3578 3579 ad->u.net->sport = dh->dccph_sport; 3580 ad->u.net->dport = dh->dccph_dport; 3581 break; 3582 } 3583 3584 default: 3585 break; 3586 } 3587 out: 3588 return ret; 3589 } 3590 3591 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE) 3592 3593 /* Returns error only if unable to parse addresses */ 3594 static int selinux_parse_skb_ipv6(struct sk_buff *skb, 3595 struct common_audit_data *ad, u8 *proto) 3596 { 3597 u8 nexthdr; 3598 int ret = -EINVAL, offset; 3599 struct ipv6hdr _ipv6h, *ip6; 3600 __be16 frag_off; 3601 3602 offset = skb_network_offset(skb); 3603 ip6 = skb_header_pointer(skb, offset, sizeof(_ipv6h), &_ipv6h); 3604 if (ip6 == NULL) 3605 goto out; 3606 3607 ad->u.net->v6info.saddr = ip6->saddr; 3608 ad->u.net->v6info.daddr = ip6->daddr; 3609 ret = 0; 3610 3611 nexthdr = ip6->nexthdr; 3612 offset += sizeof(_ipv6h); 3613 offset = ipv6_skip_exthdr(skb, offset, &nexthdr, &frag_off); 3614 if (offset < 0) 3615 goto out; 3616 3617 if (proto) 3618 *proto = nexthdr; 3619 3620 switch (nexthdr) { 3621 case IPPROTO_TCP: { 3622 struct tcphdr _tcph, *th; 3623 3624 th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph); 3625 if (th == NULL) 3626 break; 3627 3628 ad->u.net->sport = th->source; 3629 ad->u.net->dport = th->dest; 3630 break; 3631 } 3632 3633 case IPPROTO_UDP: { 3634 struct udphdr _udph, *uh; 3635 3636 uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph); 3637 if (uh == NULL) 3638 break; 3639 3640 ad->u.net->sport = uh->source; 3641 ad->u.net->dport = uh->dest; 3642 break; 3643 } 3644 3645 case IPPROTO_DCCP: { 3646 struct dccp_hdr _dccph, *dh; 3647 3648 dh = skb_header_pointer(skb, offset, sizeof(_dccph), &_dccph); 3649 if (dh == NULL) 3650 break; 3651 3652 ad->u.net->sport = dh->dccph_sport; 3653 ad->u.net->dport = dh->dccph_dport; 3654 break; 3655 } 3656 3657 /* includes fragments */ 3658 default: 3659 break; 3660 } 3661 out: 3662 return ret; 3663 } 3664 3665 #endif /* IPV6 */ 3666 3667 static int selinux_parse_skb(struct sk_buff *skb, struct common_audit_data *ad, 3668 char **_addrp, int src, u8 *proto) 3669 { 3670 char *addrp; 3671 int ret; 3672 3673 switch (ad->u.net->family) { 3674 case PF_INET: 3675 ret = selinux_parse_skb_ipv4(skb, ad, proto); 3676 if (ret) 3677 goto parse_error; 3678 addrp = (char *)(src ? &ad->u.net->v4info.saddr : 3679 &ad->u.net->v4info.daddr); 3680 goto okay; 3681 3682 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE) 3683 case PF_INET6: 3684 ret = selinux_parse_skb_ipv6(skb, ad, proto); 3685 if (ret) 3686 goto parse_error; 3687 addrp = (char *)(src ? &ad->u.net->v6info.saddr : 3688 &ad->u.net->v6info.daddr); 3689 goto okay; 3690 #endif /* IPV6 */ 3691 default: 3692 addrp = NULL; 3693 goto okay; 3694 } 3695 3696 parse_error: 3697 printk(KERN_WARNING 3698 "SELinux: failure in selinux_parse_skb()," 3699 " unable to parse packet\n"); 3700 return ret; 3701 3702 okay: 3703 if (_addrp) 3704 *_addrp = addrp; 3705 return 0; 3706 } 3707 3708 /** 3709 * selinux_skb_peerlbl_sid - Determine the peer label of a packet 3710 * @skb: the packet 3711 * @family: protocol family 3712 * @sid: the packet's peer label SID 3713 * 3714 * Description: 3715 * Check the various different forms of network peer labeling and determine 3716 * the peer label/SID for the packet; most of the magic actually occurs in 3717 * the security server function security_net_peersid_cmp(). The function 3718 * returns zero if the value in @sid is valid (although it may be SECSID_NULL) 3719 * or -EACCES if @sid is invalid due to inconsistencies with the different 3720 * peer labels. 3721 * 3722 */ 3723 static int selinux_skb_peerlbl_sid(struct sk_buff *skb, u16 family, u32 *sid) 3724 { 3725 int err; 3726 u32 xfrm_sid; 3727 u32 nlbl_sid; 3728 u32 nlbl_type; 3729 3730 selinux_skb_xfrm_sid(skb, &xfrm_sid); 3731 selinux_netlbl_skbuff_getsid(skb, family, &nlbl_type, &nlbl_sid); 3732 3733 err = security_net_peersid_resolve(nlbl_sid, nlbl_type, xfrm_sid, sid); 3734 if (unlikely(err)) { 3735 printk(KERN_WARNING 3736 "SELinux: failure in selinux_skb_peerlbl_sid()," 3737 " unable to determine packet's peer label\n"); 3738 return -EACCES; 3739 } 3740 3741 return 0; 3742 } 3743 3744 /* socket security operations */ 3745 3746 static int socket_sockcreate_sid(const struct task_security_struct *tsec, 3747 u16 secclass, u32 *socksid) 3748 { 3749 if (tsec->sockcreate_sid > SECSID_NULL) { 3750 *socksid = tsec->sockcreate_sid; 3751 return 0; 3752 } 3753 3754 return security_transition_sid(tsec->sid, tsec->sid, secclass, NULL, 3755 socksid); 3756 } 3757 3758 static int sock_has_perm(struct task_struct *task, struct sock *sk, u32 perms) 3759 { 3760 struct sk_security_struct *sksec = sk->sk_security; 3761 struct common_audit_data ad; 3762 struct selinux_audit_data sad = {0,}; 3763 struct lsm_network_audit net = {0,}; 3764 u32 tsid = task_sid(task); 3765 3766 if (sksec->sid == SECINITSID_KERNEL) 3767 return 0; 3768 3769 COMMON_AUDIT_DATA_INIT(&ad, NET); 3770 ad.selinux_audit_data = &sad; 3771 ad.u.net = &net; 3772 ad.u.net->sk = sk; 3773 3774 return avc_has_perm(tsid, sksec->sid, sksec->sclass, perms, &ad); 3775 } 3776 3777 static int selinux_socket_create(int family, int type, 3778 int protocol, int kern) 3779 { 3780 const struct task_security_struct *tsec = current_security(); 3781 u32 newsid; 3782 u16 secclass; 3783 int rc; 3784 3785 if (kern) 3786 return 0; 3787 3788 secclass = socket_type_to_security_class(family, type, protocol); 3789 rc = socket_sockcreate_sid(tsec, secclass, &newsid); 3790 if (rc) 3791 return rc; 3792 3793 return avc_has_perm(tsec->sid, newsid, secclass, SOCKET__CREATE, NULL); 3794 } 3795 3796 static int selinux_socket_post_create(struct socket *sock, int family, 3797 int type, int protocol, int kern) 3798 { 3799 const struct task_security_struct *tsec = current_security(); 3800 struct inode_security_struct *isec = SOCK_INODE(sock)->i_security; 3801 struct sk_security_struct *sksec; 3802 int err = 0; 3803 3804 isec->sclass = socket_type_to_security_class(family, type, protocol); 3805 3806 if (kern) 3807 isec->sid = SECINITSID_KERNEL; 3808 else { 3809 err = socket_sockcreate_sid(tsec, isec->sclass, &(isec->sid)); 3810 if (err) 3811 return err; 3812 } 3813 3814 isec->initialized = 1; 3815 3816 if (sock->sk) { 3817 sksec = sock->sk->sk_security; 3818 sksec->sid = isec->sid; 3819 sksec->sclass = isec->sclass; 3820 err = selinux_netlbl_socket_post_create(sock->sk, family); 3821 } 3822 3823 return err; 3824 } 3825 3826 /* Range of port numbers used to automatically bind. 3827 Need to determine whether we should perform a name_bind 3828 permission check between the socket and the port number. */ 3829 3830 static int selinux_socket_bind(struct socket *sock, struct sockaddr *address, int addrlen) 3831 { 3832 struct sock *sk = sock->sk; 3833 u16 family; 3834 int err; 3835 3836 err = sock_has_perm(current, sk, SOCKET__BIND); 3837 if (err) 3838 goto out; 3839 3840 /* 3841 * If PF_INET or PF_INET6, check name_bind permission for the port. 3842 * Multiple address binding for SCTP is not supported yet: we just 3843 * check the first address now. 3844 */ 3845 family = sk->sk_family; 3846 if (family == PF_INET || family == PF_INET6) { 3847 char *addrp; 3848 struct sk_security_struct *sksec = sk->sk_security; 3849 struct common_audit_data ad; 3850 struct selinux_audit_data sad = {0,}; 3851 struct lsm_network_audit net = {0,}; 3852 struct sockaddr_in *addr4 = NULL; 3853 struct sockaddr_in6 *addr6 = NULL; 3854 unsigned short snum; 3855 u32 sid, node_perm; 3856 3857 if (family == PF_INET) { 3858 addr4 = (struct sockaddr_in *)address; 3859 snum = ntohs(addr4->sin_port); 3860 addrp = (char *)&addr4->sin_addr.s_addr; 3861 } else { 3862 addr6 = (struct sockaddr_in6 *)address; 3863 snum = ntohs(addr6->sin6_port); 3864 addrp = (char *)&addr6->sin6_addr.s6_addr; 3865 } 3866 3867 if (snum) { 3868 int low, high; 3869 3870 inet_get_local_port_range(&low, &high); 3871 3872 if (snum < max(PROT_SOCK, low) || snum > high) { 3873 err = sel_netport_sid(sk->sk_protocol, 3874 snum, &sid); 3875 if (err) 3876 goto out; 3877 COMMON_AUDIT_DATA_INIT(&ad, NET); 3878 ad.selinux_audit_data = &sad; 3879 ad.u.net = &net; 3880 ad.u.net->sport = htons(snum); 3881 ad.u.net->family = family; 3882 err = avc_has_perm(sksec->sid, sid, 3883 sksec->sclass, 3884 SOCKET__NAME_BIND, &ad); 3885 if (err) 3886 goto out; 3887 } 3888 } 3889 3890 switch (sksec->sclass) { 3891 case SECCLASS_TCP_SOCKET: 3892 node_perm = TCP_SOCKET__NODE_BIND; 3893 break; 3894 3895 case SECCLASS_UDP_SOCKET: 3896 node_perm = UDP_SOCKET__NODE_BIND; 3897 break; 3898 3899 case SECCLASS_DCCP_SOCKET: 3900 node_perm = DCCP_SOCKET__NODE_BIND; 3901 break; 3902 3903 default: 3904 node_perm = RAWIP_SOCKET__NODE_BIND; 3905 break; 3906 } 3907 3908 err = sel_netnode_sid(addrp, family, &sid); 3909 if (err) 3910 goto out; 3911 3912 COMMON_AUDIT_DATA_INIT(&ad, NET); 3913 ad.selinux_audit_data = &sad; 3914 ad.u.net = &net; 3915 ad.u.net->sport = htons(snum); 3916 ad.u.net->family = family; 3917 3918 if (family == PF_INET) 3919 ad.u.net->v4info.saddr = addr4->sin_addr.s_addr; 3920 else 3921 ad.u.net->v6info.saddr = addr6->sin6_addr; 3922 3923 err = avc_has_perm(sksec->sid, sid, 3924 sksec->sclass, node_perm, &ad); 3925 if (err) 3926 goto out; 3927 } 3928 out: 3929 return err; 3930 } 3931 3932 static int selinux_socket_connect(struct socket *sock, struct sockaddr *address, int addrlen) 3933 { 3934 struct sock *sk = sock->sk; 3935 struct sk_security_struct *sksec = sk->sk_security; 3936 int err; 3937 3938 err = sock_has_perm(current, sk, SOCKET__CONNECT); 3939 if (err) 3940 return err; 3941 3942 /* 3943 * If a TCP or DCCP socket, check name_connect permission for the port. 3944 */ 3945 if (sksec->sclass == SECCLASS_TCP_SOCKET || 3946 sksec->sclass == SECCLASS_DCCP_SOCKET) { 3947 struct common_audit_data ad; 3948 struct selinux_audit_data sad = {0,}; 3949 struct lsm_network_audit net = {0,}; 3950 struct sockaddr_in *addr4 = NULL; 3951 struct sockaddr_in6 *addr6 = NULL; 3952 unsigned short snum; 3953 u32 sid, perm; 3954 3955 if (sk->sk_family == PF_INET) { 3956 addr4 = (struct sockaddr_in *)address; 3957 if (addrlen < sizeof(struct sockaddr_in)) 3958 return -EINVAL; 3959 snum = ntohs(addr4->sin_port); 3960 } else { 3961 addr6 = (struct sockaddr_in6 *)address; 3962 if (addrlen < SIN6_LEN_RFC2133) 3963 return -EINVAL; 3964 snum = ntohs(addr6->sin6_port); 3965 } 3966 3967 err = sel_netport_sid(sk->sk_protocol, snum, &sid); 3968 if (err) 3969 goto out; 3970 3971 perm = (sksec->sclass == SECCLASS_TCP_SOCKET) ? 3972 TCP_SOCKET__NAME_CONNECT : DCCP_SOCKET__NAME_CONNECT; 3973 3974 COMMON_AUDIT_DATA_INIT(&ad, NET); 3975 ad.selinux_audit_data = &sad; 3976 ad.u.net = &net; 3977 ad.u.net->dport = htons(snum); 3978 ad.u.net->family = sk->sk_family; 3979 err = avc_has_perm(sksec->sid, sid, sksec->sclass, perm, &ad); 3980 if (err) 3981 goto out; 3982 } 3983 3984 err = selinux_netlbl_socket_connect(sk, address); 3985 3986 out: 3987 return err; 3988 } 3989 3990 static int selinux_socket_listen(struct socket *sock, int backlog) 3991 { 3992 return sock_has_perm(current, sock->sk, SOCKET__LISTEN); 3993 } 3994 3995 static int selinux_socket_accept(struct socket *sock, struct socket *newsock) 3996 { 3997 int err; 3998 struct inode_security_struct *isec; 3999 struct inode_security_struct *newisec; 4000 4001 err = sock_has_perm(current, sock->sk, SOCKET__ACCEPT); 4002 if (err) 4003 return err; 4004 4005 newisec = SOCK_INODE(newsock)->i_security; 4006 4007 isec = SOCK_INODE(sock)->i_security; 4008 newisec->sclass = isec->sclass; 4009 newisec->sid = isec->sid; 4010 newisec->initialized = 1; 4011 4012 return 0; 4013 } 4014 4015 static int selinux_socket_sendmsg(struct socket *sock, struct msghdr *msg, 4016 int size) 4017 { 4018 return sock_has_perm(current, sock->sk, SOCKET__WRITE); 4019 } 4020 4021 static int selinux_socket_recvmsg(struct socket *sock, struct msghdr *msg, 4022 int size, int flags) 4023 { 4024 return sock_has_perm(current, sock->sk, SOCKET__READ); 4025 } 4026 4027 static int selinux_socket_getsockname(struct socket *sock) 4028 { 4029 return sock_has_perm(current, sock->sk, SOCKET__GETATTR); 4030 } 4031 4032 static int selinux_socket_getpeername(struct socket *sock) 4033 { 4034 return sock_has_perm(current, sock->sk, SOCKET__GETATTR); 4035 } 4036 4037 static int selinux_socket_setsockopt(struct socket *sock, int level, int optname) 4038 { 4039 int err; 4040 4041 err = sock_has_perm(current, sock->sk, SOCKET__SETOPT); 4042 if (err) 4043 return err; 4044 4045 return selinux_netlbl_socket_setsockopt(sock, level, optname); 4046 } 4047 4048 static int selinux_socket_getsockopt(struct socket *sock, int level, 4049 int optname) 4050 { 4051 return sock_has_perm(current, sock->sk, SOCKET__GETOPT); 4052 } 4053 4054 static int selinux_socket_shutdown(struct socket *sock, int how) 4055 { 4056 return sock_has_perm(current, sock->sk, SOCKET__SHUTDOWN); 4057 } 4058 4059 static int selinux_socket_unix_stream_connect(struct sock *sock, 4060 struct sock *other, 4061 struct sock *newsk) 4062 { 4063 struct sk_security_struct *sksec_sock = sock->sk_security; 4064 struct sk_security_struct *sksec_other = other->sk_security; 4065 struct sk_security_struct *sksec_new = newsk->sk_security; 4066 struct common_audit_data ad; 4067 struct selinux_audit_data sad = {0,}; 4068 struct lsm_network_audit net = {0,}; 4069 int err; 4070 4071 COMMON_AUDIT_DATA_INIT(&ad, NET); 4072 ad.selinux_audit_data = &sad; 4073 ad.u.net = &net; 4074 ad.u.net->sk = other; 4075 4076 err = avc_has_perm(sksec_sock->sid, sksec_other->sid, 4077 sksec_other->sclass, 4078 UNIX_STREAM_SOCKET__CONNECTTO, &ad); 4079 if (err) 4080 return err; 4081 4082 /* server child socket */ 4083 sksec_new->peer_sid = sksec_sock->sid; 4084 err = security_sid_mls_copy(sksec_other->sid, sksec_sock->sid, 4085 &sksec_new->sid); 4086 if (err) 4087 return err; 4088 4089 /* connecting socket */ 4090 sksec_sock->peer_sid = sksec_new->sid; 4091 4092 return 0; 4093 } 4094 4095 static int selinux_socket_unix_may_send(struct socket *sock, 4096 struct socket *other) 4097 { 4098 struct sk_security_struct *ssec = sock->sk->sk_security; 4099 struct sk_security_struct *osec = other->sk->sk_security; 4100 struct common_audit_data ad; 4101 struct selinux_audit_data sad = {0,}; 4102 struct lsm_network_audit net = {0,}; 4103 4104 COMMON_AUDIT_DATA_INIT(&ad, NET); 4105 ad.selinux_audit_data = &sad; 4106 ad.u.net = &net; 4107 ad.u.net->sk = other->sk; 4108 4109 return avc_has_perm(ssec->sid, osec->sid, osec->sclass, SOCKET__SENDTO, 4110 &ad); 4111 } 4112 4113 static int selinux_inet_sys_rcv_skb(int ifindex, char *addrp, u16 family, 4114 u32 peer_sid, 4115 struct common_audit_data *ad) 4116 { 4117 int err; 4118 u32 if_sid; 4119 u32 node_sid; 4120 4121 err = sel_netif_sid(ifindex, &if_sid); 4122 if (err) 4123 return err; 4124 err = avc_has_perm(peer_sid, if_sid, 4125 SECCLASS_NETIF, NETIF__INGRESS, ad); 4126 if (err) 4127 return err; 4128 4129 err = sel_netnode_sid(addrp, family, &node_sid); 4130 if (err) 4131 return err; 4132 return avc_has_perm(peer_sid, node_sid, 4133 SECCLASS_NODE, NODE__RECVFROM, ad); 4134 } 4135 4136 static int selinux_sock_rcv_skb_compat(struct sock *sk, struct sk_buff *skb, 4137 u16 family) 4138 { 4139 int err = 0; 4140 struct sk_security_struct *sksec = sk->sk_security; 4141 u32 sk_sid = sksec->sid; 4142 struct common_audit_data ad; 4143 struct selinux_audit_data sad = {0,}; 4144 struct lsm_network_audit net = {0,}; 4145 char *addrp; 4146 4147 COMMON_AUDIT_DATA_INIT(&ad, NET); 4148 ad.selinux_audit_data = &sad; 4149 ad.u.net = &net; 4150 ad.u.net->netif = skb->skb_iif; 4151 ad.u.net->family = family; 4152 err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL); 4153 if (err) 4154 return err; 4155 4156 if (selinux_secmark_enabled()) { 4157 err = avc_has_perm(sk_sid, skb->secmark, SECCLASS_PACKET, 4158 PACKET__RECV, &ad); 4159 if (err) 4160 return err; 4161 } 4162 4163 err = selinux_netlbl_sock_rcv_skb(sksec, skb, family, &ad); 4164 if (err) 4165 return err; 4166 err = selinux_xfrm_sock_rcv_skb(sksec->sid, skb, &ad); 4167 4168 return err; 4169 } 4170 4171 static int selinux_socket_sock_rcv_skb(struct sock *sk, struct sk_buff *skb) 4172 { 4173 int err; 4174 struct sk_security_struct *sksec = sk->sk_security; 4175 u16 family = sk->sk_family; 4176 u32 sk_sid = sksec->sid; 4177 struct common_audit_data ad; 4178 struct selinux_audit_data sad = {0,}; 4179 struct lsm_network_audit net = {0,}; 4180 char *addrp; 4181 u8 secmark_active; 4182 u8 peerlbl_active; 4183 4184 if (family != PF_INET && family != PF_INET6) 4185 return 0; 4186 4187 /* Handle mapped IPv4 packets arriving via IPv6 sockets */ 4188 if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP)) 4189 family = PF_INET; 4190 4191 /* If any sort of compatibility mode is enabled then handoff processing 4192 * to the selinux_sock_rcv_skb_compat() function to deal with the 4193 * special handling. We do this in an attempt to keep this function 4194 * as fast and as clean as possible. */ 4195 if (!selinux_policycap_netpeer) 4196 return selinux_sock_rcv_skb_compat(sk, skb, family); 4197 4198 secmark_active = selinux_secmark_enabled(); 4199 peerlbl_active = netlbl_enabled() || selinux_xfrm_enabled(); 4200 if (!secmark_active && !peerlbl_active) 4201 return 0; 4202 4203 COMMON_AUDIT_DATA_INIT(&ad, NET); 4204 ad.selinux_audit_data = &sad; 4205 ad.u.net = &net; 4206 ad.u.net->netif = skb->skb_iif; 4207 ad.u.net->family = family; 4208 err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL); 4209 if (err) 4210 return err; 4211 4212 if (peerlbl_active) { 4213 u32 peer_sid; 4214 4215 err = selinux_skb_peerlbl_sid(skb, family, &peer_sid); 4216 if (err) 4217 return err; 4218 err = selinux_inet_sys_rcv_skb(skb->skb_iif, addrp, family, 4219 peer_sid, &ad); 4220 if (err) { 4221 selinux_netlbl_err(skb, err, 0); 4222 return err; 4223 } 4224 err = avc_has_perm(sk_sid, peer_sid, SECCLASS_PEER, 4225 PEER__RECV, &ad); 4226 if (err) 4227 selinux_netlbl_err(skb, err, 0); 4228 } 4229 4230 if (secmark_active) { 4231 err = avc_has_perm(sk_sid, skb->secmark, SECCLASS_PACKET, 4232 PACKET__RECV, &ad); 4233 if (err) 4234 return err; 4235 } 4236 4237 return err; 4238 } 4239 4240 static int selinux_socket_getpeersec_stream(struct socket *sock, char __user *optval, 4241 int __user *optlen, unsigned len) 4242 { 4243 int err = 0; 4244 char *scontext; 4245 u32 scontext_len; 4246 struct sk_security_struct *sksec = sock->sk->sk_security; 4247 u32 peer_sid = SECSID_NULL; 4248 4249 if (sksec->sclass == SECCLASS_UNIX_STREAM_SOCKET || 4250 sksec->sclass == SECCLASS_TCP_SOCKET) 4251 peer_sid = sksec->peer_sid; 4252 if (peer_sid == SECSID_NULL) 4253 return -ENOPROTOOPT; 4254 4255 err = security_sid_to_context(peer_sid, &scontext, &scontext_len); 4256 if (err) 4257 return err; 4258 4259 if (scontext_len > len) { 4260 err = -ERANGE; 4261 goto out_len; 4262 } 4263 4264 if (copy_to_user(optval, scontext, scontext_len)) 4265 err = -EFAULT; 4266 4267 out_len: 4268 if (put_user(scontext_len, optlen)) 4269 err = -EFAULT; 4270 kfree(scontext); 4271 return err; 4272 } 4273 4274 static int selinux_socket_getpeersec_dgram(struct socket *sock, struct sk_buff *skb, u32 *secid) 4275 { 4276 u32 peer_secid = SECSID_NULL; 4277 u16 family; 4278 4279 if (skb && skb->protocol == htons(ETH_P_IP)) 4280 family = PF_INET; 4281 else if (skb && skb->protocol == htons(ETH_P_IPV6)) 4282 family = PF_INET6; 4283 else if (sock) 4284 family = sock->sk->sk_family; 4285 else 4286 goto out; 4287 4288 if (sock && family == PF_UNIX) 4289 selinux_inode_getsecid(SOCK_INODE(sock), &peer_secid); 4290 else if (skb) 4291 selinux_skb_peerlbl_sid(skb, family, &peer_secid); 4292 4293 out: 4294 *secid = peer_secid; 4295 if (peer_secid == SECSID_NULL) 4296 return -EINVAL; 4297 return 0; 4298 } 4299 4300 static int selinux_sk_alloc_security(struct sock *sk, int family, gfp_t priority) 4301 { 4302 struct sk_security_struct *sksec; 4303 4304 sksec = kzalloc(sizeof(*sksec), priority); 4305 if (!sksec) 4306 return -ENOMEM; 4307 4308 sksec->peer_sid = SECINITSID_UNLABELED; 4309 sksec->sid = SECINITSID_UNLABELED; 4310 selinux_netlbl_sk_security_reset(sksec); 4311 sk->sk_security = sksec; 4312 4313 return 0; 4314 } 4315 4316 static void selinux_sk_free_security(struct sock *sk) 4317 { 4318 struct sk_security_struct *sksec = sk->sk_security; 4319 4320 sk->sk_security = NULL; 4321 selinux_netlbl_sk_security_free(sksec); 4322 kfree(sksec); 4323 } 4324 4325 static void selinux_sk_clone_security(const struct sock *sk, struct sock *newsk) 4326 { 4327 struct sk_security_struct *sksec = sk->sk_security; 4328 struct sk_security_struct *newsksec = newsk->sk_security; 4329 4330 newsksec->sid = sksec->sid; 4331 newsksec->peer_sid = sksec->peer_sid; 4332 newsksec->sclass = sksec->sclass; 4333 4334 selinux_netlbl_sk_security_reset(newsksec); 4335 } 4336 4337 static void selinux_sk_getsecid(struct sock *sk, u32 *secid) 4338 { 4339 if (!sk) 4340 *secid = SECINITSID_ANY_SOCKET; 4341 else { 4342 struct sk_security_struct *sksec = sk->sk_security; 4343 4344 *secid = sksec->sid; 4345 } 4346 } 4347 4348 static void selinux_sock_graft(struct sock *sk, struct socket *parent) 4349 { 4350 struct inode_security_struct *isec = SOCK_INODE(parent)->i_security; 4351 struct sk_security_struct *sksec = sk->sk_security; 4352 4353 if (sk->sk_family == PF_INET || sk->sk_family == PF_INET6 || 4354 sk->sk_family == PF_UNIX) 4355 isec->sid = sksec->sid; 4356 sksec->sclass = isec->sclass; 4357 } 4358 4359 static int selinux_inet_conn_request(struct sock *sk, struct sk_buff *skb, 4360 struct request_sock *req) 4361 { 4362 struct sk_security_struct *sksec = sk->sk_security; 4363 int err; 4364 u16 family = sk->sk_family; 4365 u32 newsid; 4366 u32 peersid; 4367 4368 /* handle mapped IPv4 packets arriving via IPv6 sockets */ 4369 if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP)) 4370 family = PF_INET; 4371 4372 err = selinux_skb_peerlbl_sid(skb, family, &peersid); 4373 if (err) 4374 return err; 4375 if (peersid == SECSID_NULL) { 4376 req->secid = sksec->sid; 4377 req->peer_secid = SECSID_NULL; 4378 } else { 4379 err = security_sid_mls_copy(sksec->sid, peersid, &newsid); 4380 if (err) 4381 return err; 4382 req->secid = newsid; 4383 req->peer_secid = peersid; 4384 } 4385 4386 return selinux_netlbl_inet_conn_request(req, family); 4387 } 4388 4389 static void selinux_inet_csk_clone(struct sock *newsk, 4390 const struct request_sock *req) 4391 { 4392 struct sk_security_struct *newsksec = newsk->sk_security; 4393 4394 newsksec->sid = req->secid; 4395 newsksec->peer_sid = req->peer_secid; 4396 /* NOTE: Ideally, we should also get the isec->sid for the 4397 new socket in sync, but we don't have the isec available yet. 4398 So we will wait until sock_graft to do it, by which 4399 time it will have been created and available. */ 4400 4401 /* We don't need to take any sort of lock here as we are the only 4402 * thread with access to newsksec */ 4403 selinux_netlbl_inet_csk_clone(newsk, req->rsk_ops->family); 4404 } 4405 4406 static void selinux_inet_conn_established(struct sock *sk, struct sk_buff *skb) 4407 { 4408 u16 family = sk->sk_family; 4409 struct sk_security_struct *sksec = sk->sk_security; 4410 4411 /* handle mapped IPv4 packets arriving via IPv6 sockets */ 4412 if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP)) 4413 family = PF_INET; 4414 4415 selinux_skb_peerlbl_sid(skb, family, &sksec->peer_sid); 4416 } 4417 4418 static int selinux_secmark_relabel_packet(u32 sid) 4419 { 4420 const struct task_security_struct *__tsec; 4421 u32 tsid; 4422 4423 __tsec = current_security(); 4424 tsid = __tsec->sid; 4425 4426 return avc_has_perm(tsid, sid, SECCLASS_PACKET, PACKET__RELABELTO, NULL); 4427 } 4428 4429 static void selinux_secmark_refcount_inc(void) 4430 { 4431 atomic_inc(&selinux_secmark_refcount); 4432 } 4433 4434 static void selinux_secmark_refcount_dec(void) 4435 { 4436 atomic_dec(&selinux_secmark_refcount); 4437 } 4438 4439 static void selinux_req_classify_flow(const struct request_sock *req, 4440 struct flowi *fl) 4441 { 4442 fl->flowi_secid = req->secid; 4443 } 4444 4445 static int selinux_tun_dev_create(void) 4446 { 4447 u32 sid = current_sid(); 4448 4449 /* we aren't taking into account the "sockcreate" SID since the socket 4450 * that is being created here is not a socket in the traditional sense, 4451 * instead it is a private sock, accessible only to the kernel, and 4452 * representing a wide range of network traffic spanning multiple 4453 * connections unlike traditional sockets - check the TUN driver to 4454 * get a better understanding of why this socket is special */ 4455 4456 return avc_has_perm(sid, sid, SECCLASS_TUN_SOCKET, TUN_SOCKET__CREATE, 4457 NULL); 4458 } 4459 4460 static void selinux_tun_dev_post_create(struct sock *sk) 4461 { 4462 struct sk_security_struct *sksec = sk->sk_security; 4463 4464 /* we don't currently perform any NetLabel based labeling here and it 4465 * isn't clear that we would want to do so anyway; while we could apply 4466 * labeling without the support of the TUN user the resulting labeled 4467 * traffic from the other end of the connection would almost certainly 4468 * cause confusion to the TUN user that had no idea network labeling 4469 * protocols were being used */ 4470 4471 /* see the comments in selinux_tun_dev_create() about why we don't use 4472 * the sockcreate SID here */ 4473 4474 sksec->sid = current_sid(); 4475 sksec->sclass = SECCLASS_TUN_SOCKET; 4476 } 4477 4478 static int selinux_tun_dev_attach(struct sock *sk) 4479 { 4480 struct sk_security_struct *sksec = sk->sk_security; 4481 u32 sid = current_sid(); 4482 int err; 4483 4484 err = avc_has_perm(sid, sksec->sid, SECCLASS_TUN_SOCKET, 4485 TUN_SOCKET__RELABELFROM, NULL); 4486 if (err) 4487 return err; 4488 err = avc_has_perm(sid, sid, SECCLASS_TUN_SOCKET, 4489 TUN_SOCKET__RELABELTO, NULL); 4490 if (err) 4491 return err; 4492 4493 sksec->sid = sid; 4494 4495 return 0; 4496 } 4497 4498 static int selinux_nlmsg_perm(struct sock *sk, struct sk_buff *skb) 4499 { 4500 int err = 0; 4501 u32 perm; 4502 struct nlmsghdr *nlh; 4503 struct sk_security_struct *sksec = sk->sk_security; 4504 4505 if (skb->len < NLMSG_SPACE(0)) { 4506 err = -EINVAL; 4507 goto out; 4508 } 4509 nlh = nlmsg_hdr(skb); 4510 4511 err = selinux_nlmsg_lookup(sksec->sclass, nlh->nlmsg_type, &perm); 4512 if (err) { 4513 if (err == -EINVAL) { 4514 audit_log(current->audit_context, GFP_KERNEL, AUDIT_SELINUX_ERR, 4515 "SELinux: unrecognized netlink message" 4516 " type=%hu for sclass=%hu\n", 4517 nlh->nlmsg_type, sksec->sclass); 4518 if (!selinux_enforcing || security_get_allow_unknown()) 4519 err = 0; 4520 } 4521 4522 /* Ignore */ 4523 if (err == -ENOENT) 4524 err = 0; 4525 goto out; 4526 } 4527 4528 err = sock_has_perm(current, sk, perm); 4529 out: 4530 return err; 4531 } 4532 4533 #ifdef CONFIG_NETFILTER 4534 4535 static unsigned int selinux_ip_forward(struct sk_buff *skb, int ifindex, 4536 u16 family) 4537 { 4538 int err; 4539 char *addrp; 4540 u32 peer_sid; 4541 struct common_audit_data ad; 4542 struct selinux_audit_data sad = {0,}; 4543 struct lsm_network_audit net = {0,}; 4544 u8 secmark_active; 4545 u8 netlbl_active; 4546 u8 peerlbl_active; 4547 4548 if (!selinux_policycap_netpeer) 4549 return NF_ACCEPT; 4550 4551 secmark_active = selinux_secmark_enabled(); 4552 netlbl_active = netlbl_enabled(); 4553 peerlbl_active = netlbl_active || selinux_xfrm_enabled(); 4554 if (!secmark_active && !peerlbl_active) 4555 return NF_ACCEPT; 4556 4557 if (selinux_skb_peerlbl_sid(skb, family, &peer_sid) != 0) 4558 return NF_DROP; 4559 4560 COMMON_AUDIT_DATA_INIT(&ad, NET); 4561 ad.selinux_audit_data = &sad; 4562 ad.u.net = &net; 4563 ad.u.net->netif = ifindex; 4564 ad.u.net->family = family; 4565 if (selinux_parse_skb(skb, &ad, &addrp, 1, NULL) != 0) 4566 return NF_DROP; 4567 4568 if (peerlbl_active) { 4569 err = selinux_inet_sys_rcv_skb(ifindex, addrp, family, 4570 peer_sid, &ad); 4571 if (err) { 4572 selinux_netlbl_err(skb, err, 1); 4573 return NF_DROP; 4574 } 4575 } 4576 4577 if (secmark_active) 4578 if (avc_has_perm(peer_sid, skb->secmark, 4579 SECCLASS_PACKET, PACKET__FORWARD_IN, &ad)) 4580 return NF_DROP; 4581 4582 if (netlbl_active) 4583 /* we do this in the FORWARD path and not the POST_ROUTING 4584 * path because we want to make sure we apply the necessary 4585 * labeling before IPsec is applied so we can leverage AH 4586 * protection */ 4587 if (selinux_netlbl_skbuff_setsid(skb, family, peer_sid) != 0) 4588 return NF_DROP; 4589 4590 return NF_ACCEPT; 4591 } 4592 4593 static unsigned int selinux_ipv4_forward(unsigned int hooknum, 4594 struct sk_buff *skb, 4595 const struct net_device *in, 4596 const struct net_device *out, 4597 int (*okfn)(struct sk_buff *)) 4598 { 4599 return selinux_ip_forward(skb, in->ifindex, PF_INET); 4600 } 4601 4602 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE) 4603 static unsigned int selinux_ipv6_forward(unsigned int hooknum, 4604 struct sk_buff *skb, 4605 const struct net_device *in, 4606 const struct net_device *out, 4607 int (*okfn)(struct sk_buff *)) 4608 { 4609 return selinux_ip_forward(skb, in->ifindex, PF_INET6); 4610 } 4611 #endif /* IPV6 */ 4612 4613 static unsigned int selinux_ip_output(struct sk_buff *skb, 4614 u16 family) 4615 { 4616 u32 sid; 4617 4618 if (!netlbl_enabled()) 4619 return NF_ACCEPT; 4620 4621 /* we do this in the LOCAL_OUT path and not the POST_ROUTING path 4622 * because we want to make sure we apply the necessary labeling 4623 * before IPsec is applied so we can leverage AH protection */ 4624 if (skb->sk) { 4625 struct sk_security_struct *sksec = skb->sk->sk_security; 4626 sid = sksec->sid; 4627 } else 4628 sid = SECINITSID_KERNEL; 4629 if (selinux_netlbl_skbuff_setsid(skb, family, sid) != 0) 4630 return NF_DROP; 4631 4632 return NF_ACCEPT; 4633 } 4634 4635 static unsigned int selinux_ipv4_output(unsigned int hooknum, 4636 struct sk_buff *skb, 4637 const struct net_device *in, 4638 const struct net_device *out, 4639 int (*okfn)(struct sk_buff *)) 4640 { 4641 return selinux_ip_output(skb, PF_INET); 4642 } 4643 4644 static unsigned int selinux_ip_postroute_compat(struct sk_buff *skb, 4645 int ifindex, 4646 u16 family) 4647 { 4648 struct sock *sk = skb->sk; 4649 struct sk_security_struct *sksec; 4650 struct common_audit_data ad; 4651 struct selinux_audit_data sad = {0,}; 4652 struct lsm_network_audit net = {0,}; 4653 char *addrp; 4654 u8 proto; 4655 4656 if (sk == NULL) 4657 return NF_ACCEPT; 4658 sksec = sk->sk_security; 4659 4660 COMMON_AUDIT_DATA_INIT(&ad, NET); 4661 ad.selinux_audit_data = &sad; 4662 ad.u.net = &net; 4663 ad.u.net->netif = ifindex; 4664 ad.u.net->family = family; 4665 if (selinux_parse_skb(skb, &ad, &addrp, 0, &proto)) 4666 return NF_DROP; 4667 4668 if (selinux_secmark_enabled()) 4669 if (avc_has_perm(sksec->sid, skb->secmark, 4670 SECCLASS_PACKET, PACKET__SEND, &ad)) 4671 return NF_DROP_ERR(-ECONNREFUSED); 4672 4673 if (selinux_xfrm_postroute_last(sksec->sid, skb, &ad, proto)) 4674 return NF_DROP_ERR(-ECONNREFUSED); 4675 4676 return NF_ACCEPT; 4677 } 4678 4679 static unsigned int selinux_ip_postroute(struct sk_buff *skb, int ifindex, 4680 u16 family) 4681 { 4682 u32 secmark_perm; 4683 u32 peer_sid; 4684 struct sock *sk; 4685 struct common_audit_data ad; 4686 struct selinux_audit_data sad = {0,}; 4687 struct lsm_network_audit net = {0,}; 4688 char *addrp; 4689 u8 secmark_active; 4690 u8 peerlbl_active; 4691 4692 /* If any sort of compatibility mode is enabled then handoff processing 4693 * to the selinux_ip_postroute_compat() function to deal with the 4694 * special handling. We do this in an attempt to keep this function 4695 * as fast and as clean as possible. */ 4696 if (!selinux_policycap_netpeer) 4697 return selinux_ip_postroute_compat(skb, ifindex, family); 4698 #ifdef CONFIG_XFRM 4699 /* If skb->dst->xfrm is non-NULL then the packet is undergoing an IPsec 4700 * packet transformation so allow the packet to pass without any checks 4701 * since we'll have another chance to perform access control checks 4702 * when the packet is on it's final way out. 4703 * NOTE: there appear to be some IPv6 multicast cases where skb->dst 4704 * is NULL, in this case go ahead and apply access control. */ 4705 if (skb_dst(skb) != NULL && skb_dst(skb)->xfrm != NULL) 4706 return NF_ACCEPT; 4707 #endif 4708 secmark_active = selinux_secmark_enabled(); 4709 peerlbl_active = netlbl_enabled() || selinux_xfrm_enabled(); 4710 if (!secmark_active && !peerlbl_active) 4711 return NF_ACCEPT; 4712 4713 /* if the packet is being forwarded then get the peer label from the 4714 * packet itself; otherwise check to see if it is from a local 4715 * application or the kernel, if from an application get the peer label 4716 * from the sending socket, otherwise use the kernel's sid */ 4717 sk = skb->sk; 4718 if (sk == NULL) { 4719 if (skb->skb_iif) { 4720 secmark_perm = PACKET__FORWARD_OUT; 4721 if (selinux_skb_peerlbl_sid(skb, family, &peer_sid)) 4722 return NF_DROP; 4723 } else { 4724 secmark_perm = PACKET__SEND; 4725 peer_sid = SECINITSID_KERNEL; 4726 } 4727 } else { 4728 struct sk_security_struct *sksec = sk->sk_security; 4729 peer_sid = sksec->sid; 4730 secmark_perm = PACKET__SEND; 4731 } 4732 4733 COMMON_AUDIT_DATA_INIT(&ad, NET); 4734 ad.selinux_audit_data = &sad; 4735 ad.u.net = &net; 4736 ad.u.net->netif = ifindex; 4737 ad.u.net->family = family; 4738 if (selinux_parse_skb(skb, &ad, &addrp, 0, NULL)) 4739 return NF_DROP; 4740 4741 if (secmark_active) 4742 if (avc_has_perm(peer_sid, skb->secmark, 4743 SECCLASS_PACKET, secmark_perm, &ad)) 4744 return NF_DROP_ERR(-ECONNREFUSED); 4745 4746 if (peerlbl_active) { 4747 u32 if_sid; 4748 u32 node_sid; 4749 4750 if (sel_netif_sid(ifindex, &if_sid)) 4751 return NF_DROP; 4752 if (avc_has_perm(peer_sid, if_sid, 4753 SECCLASS_NETIF, NETIF__EGRESS, &ad)) 4754 return NF_DROP_ERR(-ECONNREFUSED); 4755 4756 if (sel_netnode_sid(addrp, family, &node_sid)) 4757 return NF_DROP; 4758 if (avc_has_perm(peer_sid, node_sid, 4759 SECCLASS_NODE, NODE__SENDTO, &ad)) 4760 return NF_DROP_ERR(-ECONNREFUSED); 4761 } 4762 4763 return NF_ACCEPT; 4764 } 4765 4766 static unsigned int selinux_ipv4_postroute(unsigned int hooknum, 4767 struct sk_buff *skb, 4768 const struct net_device *in, 4769 const struct net_device *out, 4770 int (*okfn)(struct sk_buff *)) 4771 { 4772 return selinux_ip_postroute(skb, out->ifindex, PF_INET); 4773 } 4774 4775 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE) 4776 static unsigned int selinux_ipv6_postroute(unsigned int hooknum, 4777 struct sk_buff *skb, 4778 const struct net_device *in, 4779 const struct net_device *out, 4780 int (*okfn)(struct sk_buff *)) 4781 { 4782 return selinux_ip_postroute(skb, out->ifindex, PF_INET6); 4783 } 4784 #endif /* IPV6 */ 4785 4786 #endif /* CONFIG_NETFILTER */ 4787 4788 static int selinux_netlink_send(struct sock *sk, struct sk_buff *skb) 4789 { 4790 int err; 4791 4792 err = cap_netlink_send(sk, skb); 4793 if (err) 4794 return err; 4795 4796 return selinux_nlmsg_perm(sk, skb); 4797 } 4798 4799 static int ipc_alloc_security(struct task_struct *task, 4800 struct kern_ipc_perm *perm, 4801 u16 sclass) 4802 { 4803 struct ipc_security_struct *isec; 4804 u32 sid; 4805 4806 isec = kzalloc(sizeof(struct ipc_security_struct), GFP_KERNEL); 4807 if (!isec) 4808 return -ENOMEM; 4809 4810 sid = task_sid(task); 4811 isec->sclass = sclass; 4812 isec->sid = sid; 4813 perm->security = isec; 4814 4815 return 0; 4816 } 4817 4818 static void ipc_free_security(struct kern_ipc_perm *perm) 4819 { 4820 struct ipc_security_struct *isec = perm->security; 4821 perm->security = NULL; 4822 kfree(isec); 4823 } 4824 4825 static int msg_msg_alloc_security(struct msg_msg *msg) 4826 { 4827 struct msg_security_struct *msec; 4828 4829 msec = kzalloc(sizeof(struct msg_security_struct), GFP_KERNEL); 4830 if (!msec) 4831 return -ENOMEM; 4832 4833 msec->sid = SECINITSID_UNLABELED; 4834 msg->security = msec; 4835 4836 return 0; 4837 } 4838 4839 static void msg_msg_free_security(struct msg_msg *msg) 4840 { 4841 struct msg_security_struct *msec = msg->security; 4842 4843 msg->security = NULL; 4844 kfree(msec); 4845 } 4846 4847 static int ipc_has_perm(struct kern_ipc_perm *ipc_perms, 4848 u32 perms) 4849 { 4850 struct ipc_security_struct *isec; 4851 struct common_audit_data ad; 4852 struct selinux_audit_data sad = {0,}; 4853 u32 sid = current_sid(); 4854 4855 isec = ipc_perms->security; 4856 4857 COMMON_AUDIT_DATA_INIT(&ad, IPC); 4858 ad.selinux_audit_data = &sad; 4859 ad.u.ipc_id = ipc_perms->key; 4860 4861 return avc_has_perm(sid, isec->sid, isec->sclass, perms, &ad); 4862 } 4863 4864 static int selinux_msg_msg_alloc_security(struct msg_msg *msg) 4865 { 4866 return msg_msg_alloc_security(msg); 4867 } 4868 4869 static void selinux_msg_msg_free_security(struct msg_msg *msg) 4870 { 4871 msg_msg_free_security(msg); 4872 } 4873 4874 /* message queue security operations */ 4875 static int selinux_msg_queue_alloc_security(struct msg_queue *msq) 4876 { 4877 struct ipc_security_struct *isec; 4878 struct common_audit_data ad; 4879 struct selinux_audit_data sad = {0,}; 4880 u32 sid = current_sid(); 4881 int rc; 4882 4883 rc = ipc_alloc_security(current, &msq->q_perm, SECCLASS_MSGQ); 4884 if (rc) 4885 return rc; 4886 4887 isec = msq->q_perm.security; 4888 4889 COMMON_AUDIT_DATA_INIT(&ad, IPC); 4890 ad.selinux_audit_data = &sad; 4891 ad.u.ipc_id = msq->q_perm.key; 4892 4893 rc = avc_has_perm(sid, isec->sid, SECCLASS_MSGQ, 4894 MSGQ__CREATE, &ad); 4895 if (rc) { 4896 ipc_free_security(&msq->q_perm); 4897 return rc; 4898 } 4899 return 0; 4900 } 4901 4902 static void selinux_msg_queue_free_security(struct msg_queue *msq) 4903 { 4904 ipc_free_security(&msq->q_perm); 4905 } 4906 4907 static int selinux_msg_queue_associate(struct msg_queue *msq, int msqflg) 4908 { 4909 struct ipc_security_struct *isec; 4910 struct common_audit_data ad; 4911 struct selinux_audit_data sad = {0,}; 4912 u32 sid = current_sid(); 4913 4914 isec = msq->q_perm.security; 4915 4916 COMMON_AUDIT_DATA_INIT(&ad, IPC); 4917 ad.selinux_audit_data = &sad; 4918 ad.u.ipc_id = msq->q_perm.key; 4919 4920 return avc_has_perm(sid, isec->sid, SECCLASS_MSGQ, 4921 MSGQ__ASSOCIATE, &ad); 4922 } 4923 4924 static int selinux_msg_queue_msgctl(struct msg_queue *msq, int cmd) 4925 { 4926 int err; 4927 int perms; 4928 4929 switch (cmd) { 4930 case IPC_INFO: 4931 case MSG_INFO: 4932 /* No specific object, just general system-wide information. */ 4933 return task_has_system(current, SYSTEM__IPC_INFO); 4934 case IPC_STAT: 4935 case MSG_STAT: 4936 perms = MSGQ__GETATTR | MSGQ__ASSOCIATE; 4937 break; 4938 case IPC_SET: 4939 perms = MSGQ__SETATTR; 4940 break; 4941 case IPC_RMID: 4942 perms = MSGQ__DESTROY; 4943 break; 4944 default: 4945 return 0; 4946 } 4947 4948 err = ipc_has_perm(&msq->q_perm, perms); 4949 return err; 4950 } 4951 4952 static int selinux_msg_queue_msgsnd(struct msg_queue *msq, struct msg_msg *msg, int msqflg) 4953 { 4954 struct ipc_security_struct *isec; 4955 struct msg_security_struct *msec; 4956 struct common_audit_data ad; 4957 struct selinux_audit_data sad = {0,}; 4958 u32 sid = current_sid(); 4959 int rc; 4960 4961 isec = msq->q_perm.security; 4962 msec = msg->security; 4963 4964 /* 4965 * First time through, need to assign label to the message 4966 */ 4967 if (msec->sid == SECINITSID_UNLABELED) { 4968 /* 4969 * Compute new sid based on current process and 4970 * message queue this message will be stored in 4971 */ 4972 rc = security_transition_sid(sid, isec->sid, SECCLASS_MSG, 4973 NULL, &msec->sid); 4974 if (rc) 4975 return rc; 4976 } 4977 4978 COMMON_AUDIT_DATA_INIT(&ad, IPC); 4979 ad.selinux_audit_data = &sad; 4980 ad.u.ipc_id = msq->q_perm.key; 4981 4982 /* Can this process write to the queue? */ 4983 rc = avc_has_perm(sid, isec->sid, SECCLASS_MSGQ, 4984 MSGQ__WRITE, &ad); 4985 if (!rc) 4986 /* Can this process send the message */ 4987 rc = avc_has_perm(sid, msec->sid, SECCLASS_MSG, 4988 MSG__SEND, &ad); 4989 if (!rc) 4990 /* Can the message be put in the queue? */ 4991 rc = avc_has_perm(msec->sid, isec->sid, SECCLASS_MSGQ, 4992 MSGQ__ENQUEUE, &ad); 4993 4994 return rc; 4995 } 4996 4997 static int selinux_msg_queue_msgrcv(struct msg_queue *msq, struct msg_msg *msg, 4998 struct task_struct *target, 4999 long type, int mode) 5000 { 5001 struct ipc_security_struct *isec; 5002 struct msg_security_struct *msec; 5003 struct common_audit_data ad; 5004 struct selinux_audit_data sad = {0,}; 5005 u32 sid = task_sid(target); 5006 int rc; 5007 5008 isec = msq->q_perm.security; 5009 msec = msg->security; 5010 5011 COMMON_AUDIT_DATA_INIT(&ad, IPC); 5012 ad.selinux_audit_data = &sad; 5013 ad.u.ipc_id = msq->q_perm.key; 5014 5015 rc = avc_has_perm(sid, isec->sid, 5016 SECCLASS_MSGQ, MSGQ__READ, &ad); 5017 if (!rc) 5018 rc = avc_has_perm(sid, msec->sid, 5019 SECCLASS_MSG, MSG__RECEIVE, &ad); 5020 return rc; 5021 } 5022 5023 /* Shared Memory security operations */ 5024 static int selinux_shm_alloc_security(struct shmid_kernel *shp) 5025 { 5026 struct ipc_security_struct *isec; 5027 struct common_audit_data ad; 5028 struct selinux_audit_data sad = {0,}; 5029 u32 sid = current_sid(); 5030 int rc; 5031 5032 rc = ipc_alloc_security(current, &shp->shm_perm, SECCLASS_SHM); 5033 if (rc) 5034 return rc; 5035 5036 isec = shp->shm_perm.security; 5037 5038 COMMON_AUDIT_DATA_INIT(&ad, IPC); 5039 ad.selinux_audit_data = &sad; 5040 ad.u.ipc_id = shp->shm_perm.key; 5041 5042 rc = avc_has_perm(sid, isec->sid, SECCLASS_SHM, 5043 SHM__CREATE, &ad); 5044 if (rc) { 5045 ipc_free_security(&shp->shm_perm); 5046 return rc; 5047 } 5048 return 0; 5049 } 5050 5051 static void selinux_shm_free_security(struct shmid_kernel *shp) 5052 { 5053 ipc_free_security(&shp->shm_perm); 5054 } 5055 5056 static int selinux_shm_associate(struct shmid_kernel *shp, int shmflg) 5057 { 5058 struct ipc_security_struct *isec; 5059 struct common_audit_data ad; 5060 struct selinux_audit_data sad = {0,}; 5061 u32 sid = current_sid(); 5062 5063 isec = shp->shm_perm.security; 5064 5065 COMMON_AUDIT_DATA_INIT(&ad, IPC); 5066 ad.selinux_audit_data = &sad; 5067 ad.u.ipc_id = shp->shm_perm.key; 5068 5069 return avc_has_perm(sid, isec->sid, SECCLASS_SHM, 5070 SHM__ASSOCIATE, &ad); 5071 } 5072 5073 /* Note, at this point, shp is locked down */ 5074 static int selinux_shm_shmctl(struct shmid_kernel *shp, int cmd) 5075 { 5076 int perms; 5077 int err; 5078 5079 switch (cmd) { 5080 case IPC_INFO: 5081 case SHM_INFO: 5082 /* No specific object, just general system-wide information. */ 5083 return task_has_system(current, SYSTEM__IPC_INFO); 5084 case IPC_STAT: 5085 case SHM_STAT: 5086 perms = SHM__GETATTR | SHM__ASSOCIATE; 5087 break; 5088 case IPC_SET: 5089 perms = SHM__SETATTR; 5090 break; 5091 case SHM_LOCK: 5092 case SHM_UNLOCK: 5093 perms = SHM__LOCK; 5094 break; 5095 case IPC_RMID: 5096 perms = SHM__DESTROY; 5097 break; 5098 default: 5099 return 0; 5100 } 5101 5102 err = ipc_has_perm(&shp->shm_perm, perms); 5103 return err; 5104 } 5105 5106 static int selinux_shm_shmat(struct shmid_kernel *shp, 5107 char __user *shmaddr, int shmflg) 5108 { 5109 u32 perms; 5110 5111 if (shmflg & SHM_RDONLY) 5112 perms = SHM__READ; 5113 else 5114 perms = SHM__READ | SHM__WRITE; 5115 5116 return ipc_has_perm(&shp->shm_perm, perms); 5117 } 5118 5119 /* Semaphore security operations */ 5120 static int selinux_sem_alloc_security(struct sem_array *sma) 5121 { 5122 struct ipc_security_struct *isec; 5123 struct common_audit_data ad; 5124 struct selinux_audit_data sad = {0,}; 5125 u32 sid = current_sid(); 5126 int rc; 5127 5128 rc = ipc_alloc_security(current, &sma->sem_perm, SECCLASS_SEM); 5129 if (rc) 5130 return rc; 5131 5132 isec = sma->sem_perm.security; 5133 5134 COMMON_AUDIT_DATA_INIT(&ad, IPC); 5135 ad.selinux_audit_data = &sad; 5136 ad.u.ipc_id = sma->sem_perm.key; 5137 5138 rc = avc_has_perm(sid, isec->sid, SECCLASS_SEM, 5139 SEM__CREATE, &ad); 5140 if (rc) { 5141 ipc_free_security(&sma->sem_perm); 5142 return rc; 5143 } 5144 return 0; 5145 } 5146 5147 static void selinux_sem_free_security(struct sem_array *sma) 5148 { 5149 ipc_free_security(&sma->sem_perm); 5150 } 5151 5152 static int selinux_sem_associate(struct sem_array *sma, int semflg) 5153 { 5154 struct ipc_security_struct *isec; 5155 struct common_audit_data ad; 5156 struct selinux_audit_data sad = {0,}; 5157 u32 sid = current_sid(); 5158 5159 isec = sma->sem_perm.security; 5160 5161 COMMON_AUDIT_DATA_INIT(&ad, IPC); 5162 ad.selinux_audit_data = &sad; 5163 ad.u.ipc_id = sma->sem_perm.key; 5164 5165 return avc_has_perm(sid, isec->sid, SECCLASS_SEM, 5166 SEM__ASSOCIATE, &ad); 5167 } 5168 5169 /* Note, at this point, sma is locked down */ 5170 static int selinux_sem_semctl(struct sem_array *sma, int cmd) 5171 { 5172 int err; 5173 u32 perms; 5174 5175 switch (cmd) { 5176 case IPC_INFO: 5177 case SEM_INFO: 5178 /* No specific object, just general system-wide information. */ 5179 return task_has_system(current, SYSTEM__IPC_INFO); 5180 case GETPID: 5181 case GETNCNT: 5182 case GETZCNT: 5183 perms = SEM__GETATTR; 5184 break; 5185 case GETVAL: 5186 case GETALL: 5187 perms = SEM__READ; 5188 break; 5189 case SETVAL: 5190 case SETALL: 5191 perms = SEM__WRITE; 5192 break; 5193 case IPC_RMID: 5194 perms = SEM__DESTROY; 5195 break; 5196 case IPC_SET: 5197 perms = SEM__SETATTR; 5198 break; 5199 case IPC_STAT: 5200 case SEM_STAT: 5201 perms = SEM__GETATTR | SEM__ASSOCIATE; 5202 break; 5203 default: 5204 return 0; 5205 } 5206 5207 err = ipc_has_perm(&sma->sem_perm, perms); 5208 return err; 5209 } 5210 5211 static int selinux_sem_semop(struct sem_array *sma, 5212 struct sembuf *sops, unsigned nsops, int alter) 5213 { 5214 u32 perms; 5215 5216 if (alter) 5217 perms = SEM__READ | SEM__WRITE; 5218 else 5219 perms = SEM__READ; 5220 5221 return ipc_has_perm(&sma->sem_perm, perms); 5222 } 5223 5224 static int selinux_ipc_permission(struct kern_ipc_perm *ipcp, short flag) 5225 { 5226 u32 av = 0; 5227 5228 av = 0; 5229 if (flag & S_IRUGO) 5230 av |= IPC__UNIX_READ; 5231 if (flag & S_IWUGO) 5232 av |= IPC__UNIX_WRITE; 5233 5234 if (av == 0) 5235 return 0; 5236 5237 return ipc_has_perm(ipcp, av); 5238 } 5239 5240 static void selinux_ipc_getsecid(struct kern_ipc_perm *ipcp, u32 *secid) 5241 { 5242 struct ipc_security_struct *isec = ipcp->security; 5243 *secid = isec->sid; 5244 } 5245 5246 static void selinux_d_instantiate(struct dentry *dentry, struct inode *inode) 5247 { 5248 if (inode) 5249 inode_doinit_with_dentry(inode, dentry); 5250 } 5251 5252 static int selinux_getprocattr(struct task_struct *p, 5253 char *name, char **value) 5254 { 5255 const struct task_security_struct *__tsec; 5256 u32 sid; 5257 int error; 5258 unsigned len; 5259 5260 if (current != p) { 5261 error = current_has_perm(p, PROCESS__GETATTR); 5262 if (error) 5263 return error; 5264 } 5265 5266 rcu_read_lock(); 5267 __tsec = __task_cred(p)->security; 5268 5269 if (!strcmp(name, "current")) 5270 sid = __tsec->sid; 5271 else if (!strcmp(name, "prev")) 5272 sid = __tsec->osid; 5273 else if (!strcmp(name, "exec")) 5274 sid = __tsec->exec_sid; 5275 else if (!strcmp(name, "fscreate")) 5276 sid = __tsec->create_sid; 5277 else if (!strcmp(name, "keycreate")) 5278 sid = __tsec->keycreate_sid; 5279 else if (!strcmp(name, "sockcreate")) 5280 sid = __tsec->sockcreate_sid; 5281 else 5282 goto invalid; 5283 rcu_read_unlock(); 5284 5285 if (!sid) 5286 return 0; 5287 5288 error = security_sid_to_context(sid, value, &len); 5289 if (error) 5290 return error; 5291 return len; 5292 5293 invalid: 5294 rcu_read_unlock(); 5295 return -EINVAL; 5296 } 5297 5298 static int selinux_setprocattr(struct task_struct *p, 5299 char *name, void *value, size_t size) 5300 { 5301 struct task_security_struct *tsec; 5302 struct task_struct *tracer; 5303 struct cred *new; 5304 u32 sid = 0, ptsid; 5305 int error; 5306 char *str = value; 5307 5308 if (current != p) { 5309 /* SELinux only allows a process to change its own 5310 security attributes. */ 5311 return -EACCES; 5312 } 5313 5314 /* 5315 * Basic control over ability to set these attributes at all. 5316 * current == p, but we'll pass them separately in case the 5317 * above restriction is ever removed. 5318 */ 5319 if (!strcmp(name, "exec")) 5320 error = current_has_perm(p, PROCESS__SETEXEC); 5321 else if (!strcmp(name, "fscreate")) 5322 error = current_has_perm(p, PROCESS__SETFSCREATE); 5323 else if (!strcmp(name, "keycreate")) 5324 error = current_has_perm(p, PROCESS__SETKEYCREATE); 5325 else if (!strcmp(name, "sockcreate")) 5326 error = current_has_perm(p, PROCESS__SETSOCKCREATE); 5327 else if (!strcmp(name, "current")) 5328 error = current_has_perm(p, PROCESS__SETCURRENT); 5329 else 5330 error = -EINVAL; 5331 if (error) 5332 return error; 5333 5334 /* Obtain a SID for the context, if one was specified. */ 5335 if (size && str[1] && str[1] != '\n') { 5336 if (str[size-1] == '\n') { 5337 str[size-1] = 0; 5338 size--; 5339 } 5340 error = security_context_to_sid(value, size, &sid); 5341 if (error == -EINVAL && !strcmp(name, "fscreate")) { 5342 if (!capable(CAP_MAC_ADMIN)) 5343 return error; 5344 error = security_context_to_sid_force(value, size, 5345 &sid); 5346 } 5347 if (error) 5348 return error; 5349 } 5350 5351 new = prepare_creds(); 5352 if (!new) 5353 return -ENOMEM; 5354 5355 /* Permission checking based on the specified context is 5356 performed during the actual operation (execve, 5357 open/mkdir/...), when we know the full context of the 5358 operation. See selinux_bprm_set_creds for the execve 5359 checks and may_create for the file creation checks. The 5360 operation will then fail if the context is not permitted. */ 5361 tsec = new->security; 5362 if (!strcmp(name, "exec")) { 5363 tsec->exec_sid = sid; 5364 } else if (!strcmp(name, "fscreate")) { 5365 tsec->create_sid = sid; 5366 } else if (!strcmp(name, "keycreate")) { 5367 error = may_create_key(sid, p); 5368 if (error) 5369 goto abort_change; 5370 tsec->keycreate_sid = sid; 5371 } else if (!strcmp(name, "sockcreate")) { 5372 tsec->sockcreate_sid = sid; 5373 } else if (!strcmp(name, "current")) { 5374 error = -EINVAL; 5375 if (sid == 0) 5376 goto abort_change; 5377 5378 /* Only allow single threaded processes to change context */ 5379 error = -EPERM; 5380 if (!current_is_single_threaded()) { 5381 error = security_bounded_transition(tsec->sid, sid); 5382 if (error) 5383 goto abort_change; 5384 } 5385 5386 /* Check permissions for the transition. */ 5387 error = avc_has_perm(tsec->sid, sid, SECCLASS_PROCESS, 5388 PROCESS__DYNTRANSITION, NULL); 5389 if (error) 5390 goto abort_change; 5391 5392 /* Check for ptracing, and update the task SID if ok. 5393 Otherwise, leave SID unchanged and fail. */ 5394 ptsid = 0; 5395 task_lock(p); 5396 tracer = ptrace_parent(p); 5397 if (tracer) 5398 ptsid = task_sid(tracer); 5399 task_unlock(p); 5400 5401 if (tracer) { 5402 error = avc_has_perm(ptsid, sid, SECCLASS_PROCESS, 5403 PROCESS__PTRACE, NULL); 5404 if (error) 5405 goto abort_change; 5406 } 5407 5408 tsec->sid = sid; 5409 } else { 5410 error = -EINVAL; 5411 goto abort_change; 5412 } 5413 5414 commit_creds(new); 5415 return size; 5416 5417 abort_change: 5418 abort_creds(new); 5419 return error; 5420 } 5421 5422 static int selinux_secid_to_secctx(u32 secid, char **secdata, u32 *seclen) 5423 { 5424 return security_sid_to_context(secid, secdata, seclen); 5425 } 5426 5427 static int selinux_secctx_to_secid(const char *secdata, u32 seclen, u32 *secid) 5428 { 5429 return security_context_to_sid(secdata, seclen, secid); 5430 } 5431 5432 static void selinux_release_secctx(char *secdata, u32 seclen) 5433 { 5434 kfree(secdata); 5435 } 5436 5437 /* 5438 * called with inode->i_mutex locked 5439 */ 5440 static int selinux_inode_notifysecctx(struct inode *inode, void *ctx, u32 ctxlen) 5441 { 5442 return selinux_inode_setsecurity(inode, XATTR_SELINUX_SUFFIX, ctx, ctxlen, 0); 5443 } 5444 5445 /* 5446 * called with inode->i_mutex locked 5447 */ 5448 static int selinux_inode_setsecctx(struct dentry *dentry, void *ctx, u32 ctxlen) 5449 { 5450 return __vfs_setxattr_noperm(dentry, XATTR_NAME_SELINUX, ctx, ctxlen, 0); 5451 } 5452 5453 static int selinux_inode_getsecctx(struct inode *inode, void **ctx, u32 *ctxlen) 5454 { 5455 int len = 0; 5456 len = selinux_inode_getsecurity(inode, XATTR_SELINUX_SUFFIX, 5457 ctx, true); 5458 if (len < 0) 5459 return len; 5460 *ctxlen = len; 5461 return 0; 5462 } 5463 #ifdef CONFIG_KEYS 5464 5465 static int selinux_key_alloc(struct key *k, const struct cred *cred, 5466 unsigned long flags) 5467 { 5468 const struct task_security_struct *tsec; 5469 struct key_security_struct *ksec; 5470 5471 ksec = kzalloc(sizeof(struct key_security_struct), GFP_KERNEL); 5472 if (!ksec) 5473 return -ENOMEM; 5474 5475 tsec = cred->security; 5476 if (tsec->keycreate_sid) 5477 ksec->sid = tsec->keycreate_sid; 5478 else 5479 ksec->sid = tsec->sid; 5480 5481 k->security = ksec; 5482 return 0; 5483 } 5484 5485 static void selinux_key_free(struct key *k) 5486 { 5487 struct key_security_struct *ksec = k->security; 5488 5489 k->security = NULL; 5490 kfree(ksec); 5491 } 5492 5493 static int selinux_key_permission(key_ref_t key_ref, 5494 const struct cred *cred, 5495 key_perm_t perm) 5496 { 5497 struct key *key; 5498 struct key_security_struct *ksec; 5499 u32 sid; 5500 5501 /* if no specific permissions are requested, we skip the 5502 permission check. No serious, additional covert channels 5503 appear to be created. */ 5504 if (perm == 0) 5505 return 0; 5506 5507 sid = cred_sid(cred); 5508 5509 key = key_ref_to_ptr(key_ref); 5510 ksec = key->security; 5511 5512 return avc_has_perm(sid, ksec->sid, SECCLASS_KEY, perm, NULL); 5513 } 5514 5515 static int selinux_key_getsecurity(struct key *key, char **_buffer) 5516 { 5517 struct key_security_struct *ksec = key->security; 5518 char *context = NULL; 5519 unsigned len; 5520 int rc; 5521 5522 rc = security_sid_to_context(ksec->sid, &context, &len); 5523 if (!rc) 5524 rc = len; 5525 *_buffer = context; 5526 return rc; 5527 } 5528 5529 #endif 5530 5531 static struct security_operations selinux_ops = { 5532 .name = "selinux", 5533 5534 .ptrace_access_check = selinux_ptrace_access_check, 5535 .ptrace_traceme = selinux_ptrace_traceme, 5536 .capget = selinux_capget, 5537 .capset = selinux_capset, 5538 .capable = selinux_capable, 5539 .quotactl = selinux_quotactl, 5540 .quota_on = selinux_quota_on, 5541 .syslog = selinux_syslog, 5542 .vm_enough_memory = selinux_vm_enough_memory, 5543 5544 .netlink_send = selinux_netlink_send, 5545 5546 .bprm_set_creds = selinux_bprm_set_creds, 5547 .bprm_committing_creds = selinux_bprm_committing_creds, 5548 .bprm_committed_creds = selinux_bprm_committed_creds, 5549 .bprm_secureexec = selinux_bprm_secureexec, 5550 5551 .sb_alloc_security = selinux_sb_alloc_security, 5552 .sb_free_security = selinux_sb_free_security, 5553 .sb_copy_data = selinux_sb_copy_data, 5554 .sb_remount = selinux_sb_remount, 5555 .sb_kern_mount = selinux_sb_kern_mount, 5556 .sb_show_options = selinux_sb_show_options, 5557 .sb_statfs = selinux_sb_statfs, 5558 .sb_mount = selinux_mount, 5559 .sb_umount = selinux_umount, 5560 .sb_set_mnt_opts = selinux_set_mnt_opts, 5561 .sb_clone_mnt_opts = selinux_sb_clone_mnt_opts, 5562 .sb_parse_opts_str = selinux_parse_opts_str, 5563 5564 5565 .inode_alloc_security = selinux_inode_alloc_security, 5566 .inode_free_security = selinux_inode_free_security, 5567 .inode_init_security = selinux_inode_init_security, 5568 .inode_create = selinux_inode_create, 5569 .inode_link = selinux_inode_link, 5570 .inode_unlink = selinux_inode_unlink, 5571 .inode_symlink = selinux_inode_symlink, 5572 .inode_mkdir = selinux_inode_mkdir, 5573 .inode_rmdir = selinux_inode_rmdir, 5574 .inode_mknod = selinux_inode_mknod, 5575 .inode_rename = selinux_inode_rename, 5576 .inode_readlink = selinux_inode_readlink, 5577 .inode_follow_link = selinux_inode_follow_link, 5578 .inode_permission = selinux_inode_permission, 5579 .inode_setattr = selinux_inode_setattr, 5580 .inode_getattr = selinux_inode_getattr, 5581 .inode_setxattr = selinux_inode_setxattr, 5582 .inode_post_setxattr = selinux_inode_post_setxattr, 5583 .inode_getxattr = selinux_inode_getxattr, 5584 .inode_listxattr = selinux_inode_listxattr, 5585 .inode_removexattr = selinux_inode_removexattr, 5586 .inode_getsecurity = selinux_inode_getsecurity, 5587 .inode_setsecurity = selinux_inode_setsecurity, 5588 .inode_listsecurity = selinux_inode_listsecurity, 5589 .inode_getsecid = selinux_inode_getsecid, 5590 5591 .file_permission = selinux_file_permission, 5592 .file_alloc_security = selinux_file_alloc_security, 5593 .file_free_security = selinux_file_free_security, 5594 .file_ioctl = selinux_file_ioctl, 5595 .file_mmap = selinux_file_mmap, 5596 .file_mprotect = selinux_file_mprotect, 5597 .file_lock = selinux_file_lock, 5598 .file_fcntl = selinux_file_fcntl, 5599 .file_set_fowner = selinux_file_set_fowner, 5600 .file_send_sigiotask = selinux_file_send_sigiotask, 5601 .file_receive = selinux_file_receive, 5602 5603 .dentry_open = selinux_dentry_open, 5604 5605 .task_create = selinux_task_create, 5606 .cred_alloc_blank = selinux_cred_alloc_blank, 5607 .cred_free = selinux_cred_free, 5608 .cred_prepare = selinux_cred_prepare, 5609 .cred_transfer = selinux_cred_transfer, 5610 .kernel_act_as = selinux_kernel_act_as, 5611 .kernel_create_files_as = selinux_kernel_create_files_as, 5612 .kernel_module_request = selinux_kernel_module_request, 5613 .task_setpgid = selinux_task_setpgid, 5614 .task_getpgid = selinux_task_getpgid, 5615 .task_getsid = selinux_task_getsid, 5616 .task_getsecid = selinux_task_getsecid, 5617 .task_setnice = selinux_task_setnice, 5618 .task_setioprio = selinux_task_setioprio, 5619 .task_getioprio = selinux_task_getioprio, 5620 .task_setrlimit = selinux_task_setrlimit, 5621 .task_setscheduler = selinux_task_setscheduler, 5622 .task_getscheduler = selinux_task_getscheduler, 5623 .task_movememory = selinux_task_movememory, 5624 .task_kill = selinux_task_kill, 5625 .task_wait = selinux_task_wait, 5626 .task_to_inode = selinux_task_to_inode, 5627 5628 .ipc_permission = selinux_ipc_permission, 5629 .ipc_getsecid = selinux_ipc_getsecid, 5630 5631 .msg_msg_alloc_security = selinux_msg_msg_alloc_security, 5632 .msg_msg_free_security = selinux_msg_msg_free_security, 5633 5634 .msg_queue_alloc_security = selinux_msg_queue_alloc_security, 5635 .msg_queue_free_security = selinux_msg_queue_free_security, 5636 .msg_queue_associate = selinux_msg_queue_associate, 5637 .msg_queue_msgctl = selinux_msg_queue_msgctl, 5638 .msg_queue_msgsnd = selinux_msg_queue_msgsnd, 5639 .msg_queue_msgrcv = selinux_msg_queue_msgrcv, 5640 5641 .shm_alloc_security = selinux_shm_alloc_security, 5642 .shm_free_security = selinux_shm_free_security, 5643 .shm_associate = selinux_shm_associate, 5644 .shm_shmctl = selinux_shm_shmctl, 5645 .shm_shmat = selinux_shm_shmat, 5646 5647 .sem_alloc_security = selinux_sem_alloc_security, 5648 .sem_free_security = selinux_sem_free_security, 5649 .sem_associate = selinux_sem_associate, 5650 .sem_semctl = selinux_sem_semctl, 5651 .sem_semop = selinux_sem_semop, 5652 5653 .d_instantiate = selinux_d_instantiate, 5654 5655 .getprocattr = selinux_getprocattr, 5656 .setprocattr = selinux_setprocattr, 5657 5658 .secid_to_secctx = selinux_secid_to_secctx, 5659 .secctx_to_secid = selinux_secctx_to_secid, 5660 .release_secctx = selinux_release_secctx, 5661 .inode_notifysecctx = selinux_inode_notifysecctx, 5662 .inode_setsecctx = selinux_inode_setsecctx, 5663 .inode_getsecctx = selinux_inode_getsecctx, 5664 5665 .unix_stream_connect = selinux_socket_unix_stream_connect, 5666 .unix_may_send = selinux_socket_unix_may_send, 5667 5668 .socket_create = selinux_socket_create, 5669 .socket_post_create = selinux_socket_post_create, 5670 .socket_bind = selinux_socket_bind, 5671 .socket_connect = selinux_socket_connect, 5672 .socket_listen = selinux_socket_listen, 5673 .socket_accept = selinux_socket_accept, 5674 .socket_sendmsg = selinux_socket_sendmsg, 5675 .socket_recvmsg = selinux_socket_recvmsg, 5676 .socket_getsockname = selinux_socket_getsockname, 5677 .socket_getpeername = selinux_socket_getpeername, 5678 .socket_getsockopt = selinux_socket_getsockopt, 5679 .socket_setsockopt = selinux_socket_setsockopt, 5680 .socket_shutdown = selinux_socket_shutdown, 5681 .socket_sock_rcv_skb = selinux_socket_sock_rcv_skb, 5682 .socket_getpeersec_stream = selinux_socket_getpeersec_stream, 5683 .socket_getpeersec_dgram = selinux_socket_getpeersec_dgram, 5684 .sk_alloc_security = selinux_sk_alloc_security, 5685 .sk_free_security = selinux_sk_free_security, 5686 .sk_clone_security = selinux_sk_clone_security, 5687 .sk_getsecid = selinux_sk_getsecid, 5688 .sock_graft = selinux_sock_graft, 5689 .inet_conn_request = selinux_inet_conn_request, 5690 .inet_csk_clone = selinux_inet_csk_clone, 5691 .inet_conn_established = selinux_inet_conn_established, 5692 .secmark_relabel_packet = selinux_secmark_relabel_packet, 5693 .secmark_refcount_inc = selinux_secmark_refcount_inc, 5694 .secmark_refcount_dec = selinux_secmark_refcount_dec, 5695 .req_classify_flow = selinux_req_classify_flow, 5696 .tun_dev_create = selinux_tun_dev_create, 5697 .tun_dev_post_create = selinux_tun_dev_post_create, 5698 .tun_dev_attach = selinux_tun_dev_attach, 5699 5700 #ifdef CONFIG_SECURITY_NETWORK_XFRM 5701 .xfrm_policy_alloc_security = selinux_xfrm_policy_alloc, 5702 .xfrm_policy_clone_security = selinux_xfrm_policy_clone, 5703 .xfrm_policy_free_security = selinux_xfrm_policy_free, 5704 .xfrm_policy_delete_security = selinux_xfrm_policy_delete, 5705 .xfrm_state_alloc_security = selinux_xfrm_state_alloc, 5706 .xfrm_state_free_security = selinux_xfrm_state_free, 5707 .xfrm_state_delete_security = selinux_xfrm_state_delete, 5708 .xfrm_policy_lookup = selinux_xfrm_policy_lookup, 5709 .xfrm_state_pol_flow_match = selinux_xfrm_state_pol_flow_match, 5710 .xfrm_decode_session = selinux_xfrm_decode_session, 5711 #endif 5712 5713 #ifdef CONFIG_KEYS 5714 .key_alloc = selinux_key_alloc, 5715 .key_free = selinux_key_free, 5716 .key_permission = selinux_key_permission, 5717 .key_getsecurity = selinux_key_getsecurity, 5718 #endif 5719 5720 #ifdef CONFIG_AUDIT 5721 .audit_rule_init = selinux_audit_rule_init, 5722 .audit_rule_known = selinux_audit_rule_known, 5723 .audit_rule_match = selinux_audit_rule_match, 5724 .audit_rule_free = selinux_audit_rule_free, 5725 #endif 5726 }; 5727 5728 static __init int selinux_init(void) 5729 { 5730 if (!security_module_enable(&selinux_ops)) { 5731 selinux_enabled = 0; 5732 return 0; 5733 } 5734 5735 if (!selinux_enabled) { 5736 printk(KERN_INFO "SELinux: Disabled at boot.\n"); 5737 return 0; 5738 } 5739 5740 printk(KERN_INFO "SELinux: Initializing.\n"); 5741 5742 /* Set the security state for the initial task. */ 5743 cred_init_security(); 5744 5745 default_noexec = !(VM_DATA_DEFAULT_FLAGS & VM_EXEC); 5746 5747 sel_inode_cache = kmem_cache_create("selinux_inode_security", 5748 sizeof(struct inode_security_struct), 5749 0, SLAB_PANIC, NULL); 5750 avc_init(); 5751 5752 if (register_security(&selinux_ops)) 5753 panic("SELinux: Unable to register with kernel.\n"); 5754 5755 if (selinux_enforcing) 5756 printk(KERN_DEBUG "SELinux: Starting in enforcing mode\n"); 5757 else 5758 printk(KERN_DEBUG "SELinux: Starting in permissive mode\n"); 5759 5760 return 0; 5761 } 5762 5763 static void delayed_superblock_init(struct super_block *sb, void *unused) 5764 { 5765 superblock_doinit(sb, NULL); 5766 } 5767 5768 void selinux_complete_init(void) 5769 { 5770 printk(KERN_DEBUG "SELinux: Completing initialization.\n"); 5771 5772 /* Set up any superblocks initialized prior to the policy load. */ 5773 printk(KERN_DEBUG "SELinux: Setting up existing superblocks.\n"); 5774 iterate_supers(delayed_superblock_init, NULL); 5775 } 5776 5777 /* SELinux requires early initialization in order to label 5778 all processes and objects when they are created. */ 5779 security_initcall(selinux_init); 5780 5781 #if defined(CONFIG_NETFILTER) 5782 5783 static struct nf_hook_ops selinux_ipv4_ops[] = { 5784 { 5785 .hook = selinux_ipv4_postroute, 5786 .owner = THIS_MODULE, 5787 .pf = PF_INET, 5788 .hooknum = NF_INET_POST_ROUTING, 5789 .priority = NF_IP_PRI_SELINUX_LAST, 5790 }, 5791 { 5792 .hook = selinux_ipv4_forward, 5793 .owner = THIS_MODULE, 5794 .pf = PF_INET, 5795 .hooknum = NF_INET_FORWARD, 5796 .priority = NF_IP_PRI_SELINUX_FIRST, 5797 }, 5798 { 5799 .hook = selinux_ipv4_output, 5800 .owner = THIS_MODULE, 5801 .pf = PF_INET, 5802 .hooknum = NF_INET_LOCAL_OUT, 5803 .priority = NF_IP_PRI_SELINUX_FIRST, 5804 } 5805 }; 5806 5807 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE) 5808 5809 static struct nf_hook_ops selinux_ipv6_ops[] = { 5810 { 5811 .hook = selinux_ipv6_postroute, 5812 .owner = THIS_MODULE, 5813 .pf = PF_INET6, 5814 .hooknum = NF_INET_POST_ROUTING, 5815 .priority = NF_IP6_PRI_SELINUX_LAST, 5816 }, 5817 { 5818 .hook = selinux_ipv6_forward, 5819 .owner = THIS_MODULE, 5820 .pf = PF_INET6, 5821 .hooknum = NF_INET_FORWARD, 5822 .priority = NF_IP6_PRI_SELINUX_FIRST, 5823 } 5824 }; 5825 5826 #endif /* IPV6 */ 5827 5828 static int __init selinux_nf_ip_init(void) 5829 { 5830 int err = 0; 5831 5832 if (!selinux_enabled) 5833 goto out; 5834 5835 printk(KERN_DEBUG "SELinux: Registering netfilter hooks\n"); 5836 5837 err = nf_register_hooks(selinux_ipv4_ops, ARRAY_SIZE(selinux_ipv4_ops)); 5838 if (err) 5839 panic("SELinux: nf_register_hooks for IPv4: error %d\n", err); 5840 5841 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE) 5842 err = nf_register_hooks(selinux_ipv6_ops, ARRAY_SIZE(selinux_ipv6_ops)); 5843 if (err) 5844 panic("SELinux: nf_register_hooks for IPv6: error %d\n", err); 5845 #endif /* IPV6 */ 5846 5847 out: 5848 return err; 5849 } 5850 5851 __initcall(selinux_nf_ip_init); 5852 5853 #ifdef CONFIG_SECURITY_SELINUX_DISABLE 5854 static void selinux_nf_ip_exit(void) 5855 { 5856 printk(KERN_DEBUG "SELinux: Unregistering netfilter hooks\n"); 5857 5858 nf_unregister_hooks(selinux_ipv4_ops, ARRAY_SIZE(selinux_ipv4_ops)); 5859 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE) 5860 nf_unregister_hooks(selinux_ipv6_ops, ARRAY_SIZE(selinux_ipv6_ops)); 5861 #endif /* IPV6 */ 5862 } 5863 #endif 5864 5865 #else /* CONFIG_NETFILTER */ 5866 5867 #ifdef CONFIG_SECURITY_SELINUX_DISABLE 5868 #define selinux_nf_ip_exit() 5869 #endif 5870 5871 #endif /* CONFIG_NETFILTER */ 5872 5873 #ifdef CONFIG_SECURITY_SELINUX_DISABLE 5874 static int selinux_disabled; 5875 5876 int selinux_disable(void) 5877 { 5878 if (ss_initialized) { 5879 /* Not permitted after initial policy load. */ 5880 return -EINVAL; 5881 } 5882 5883 if (selinux_disabled) { 5884 /* Only do this once. */ 5885 return -EINVAL; 5886 } 5887 5888 printk(KERN_INFO "SELinux: Disabled at runtime.\n"); 5889 5890 selinux_disabled = 1; 5891 selinux_enabled = 0; 5892 5893 reset_security_ops(); 5894 5895 /* Try to destroy the avc node cache */ 5896 avc_disable(); 5897 5898 /* Unregister netfilter hooks. */ 5899 selinux_nf_ip_exit(); 5900 5901 /* Unregister selinuxfs. */ 5902 exit_sel_fs(); 5903 5904 return 0; 5905 } 5906 #endif 5907