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/lsm_hooks.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/inet_connection_sock.h> 56 #include <net/net_namespace.h> 57 #include <net/netlabel.h> 58 #include <linux/uaccess.h> 59 #include <asm/ioctls.h> 60 #include <linux/atomic.h> 61 #include <linux/bitops.h> 62 #include <linux/interrupt.h> 63 #include <linux/netdevice.h> /* for network interface checks */ 64 #include <net/netlink.h> 65 #include <linux/tcp.h> 66 #include <linux/udp.h> 67 #include <linux/dccp.h> 68 #include <linux/quota.h> 69 #include <linux/un.h> /* for Unix socket types */ 70 #include <net/af_unix.h> /* for Unix socket types */ 71 #include <linux/parser.h> 72 #include <linux/nfs_mount.h> 73 #include <net/ipv6.h> 74 #include <linux/hugetlb.h> 75 #include <linux/personality.h> 76 #include <linux/audit.h> 77 #include <linux/string.h> 78 #include <linux/selinux.h> 79 #include <linux/mutex.h> 80 #include <linux/posix-timers.h> 81 #include <linux/syslog.h> 82 #include <linux/user_namespace.h> 83 #include <linux/export.h> 84 #include <linux/msg.h> 85 #include <linux/shm.h> 86 87 #include "avc.h" 88 #include "objsec.h" 89 #include "netif.h" 90 #include "netnode.h" 91 #include "netport.h" 92 #include "xfrm.h" 93 #include "netlabel.h" 94 #include "audit.h" 95 #include "avc_ss.h" 96 97 /* SECMARK reference count */ 98 static atomic_t selinux_secmark_refcount = ATOMIC_INIT(0); 99 100 #ifdef CONFIG_SECURITY_SELINUX_DEVELOP 101 int selinux_enforcing; 102 103 static int __init enforcing_setup(char *str) 104 { 105 unsigned long enforcing; 106 if (!kstrtoul(str, 0, &enforcing)) 107 selinux_enforcing = enforcing ? 1 : 0; 108 return 1; 109 } 110 __setup("enforcing=", enforcing_setup); 111 #endif 112 113 #ifdef CONFIG_SECURITY_SELINUX_BOOTPARAM 114 int selinux_enabled = CONFIG_SECURITY_SELINUX_BOOTPARAM_VALUE; 115 116 static int __init selinux_enabled_setup(char *str) 117 { 118 unsigned long enabled; 119 if (!kstrtoul(str, 0, &enabled)) 120 selinux_enabled = enabled ? 1 : 0; 121 return 1; 122 } 123 __setup("selinux=", selinux_enabled_setup); 124 #else 125 int selinux_enabled = 1; 126 #endif 127 128 static struct kmem_cache *sel_inode_cache; 129 static struct kmem_cache *file_security_cache; 130 131 /** 132 * selinux_secmark_enabled - Check to see if SECMARK is currently enabled 133 * 134 * Description: 135 * This function checks the SECMARK reference counter to see if any SECMARK 136 * targets are currently configured, if the reference counter is greater than 137 * zero SECMARK is considered to be enabled. Returns true (1) if SECMARK is 138 * enabled, false (0) if SECMARK is disabled. If the always_check_network 139 * policy capability is enabled, SECMARK is always considered enabled. 140 * 141 */ 142 static int selinux_secmark_enabled(void) 143 { 144 return (selinux_policycap_alwaysnetwork || atomic_read(&selinux_secmark_refcount)); 145 } 146 147 /** 148 * selinux_peerlbl_enabled - Check to see if peer labeling is currently enabled 149 * 150 * Description: 151 * This function checks if NetLabel or labeled IPSEC is enabled. Returns true 152 * (1) if any are enabled or false (0) if neither are enabled. If the 153 * always_check_network policy capability is enabled, peer labeling 154 * is always considered enabled. 155 * 156 */ 157 static int selinux_peerlbl_enabled(void) 158 { 159 return (selinux_policycap_alwaysnetwork || netlbl_enabled() || selinux_xfrm_enabled()); 160 } 161 162 static int selinux_netcache_avc_callback(u32 event) 163 { 164 if (event == AVC_CALLBACK_RESET) { 165 sel_netif_flush(); 166 sel_netnode_flush(); 167 sel_netport_flush(); 168 synchronize_net(); 169 } 170 return 0; 171 } 172 173 /* 174 * initialise the security for the init task 175 */ 176 static void cred_init_security(void) 177 { 178 struct cred *cred = (struct cred *) current->real_cred; 179 struct task_security_struct *tsec; 180 181 tsec = kzalloc(sizeof(struct task_security_struct), GFP_KERNEL); 182 if (!tsec) 183 panic("SELinux: Failed to initialize initial task.\n"); 184 185 tsec->osid = tsec->sid = SECINITSID_KERNEL; 186 cred->security = tsec; 187 } 188 189 /* 190 * get the security ID of a set of credentials 191 */ 192 static inline u32 cred_sid(const struct cred *cred) 193 { 194 const struct task_security_struct *tsec; 195 196 tsec = cred->security; 197 return tsec->sid; 198 } 199 200 /* 201 * get the objective security ID of a task 202 */ 203 static inline u32 task_sid(const struct task_struct *task) 204 { 205 u32 sid; 206 207 rcu_read_lock(); 208 sid = cred_sid(__task_cred(task)); 209 rcu_read_unlock(); 210 return sid; 211 } 212 213 /* 214 * get the subjective security ID of the current task 215 */ 216 static inline u32 current_sid(void) 217 { 218 const struct task_security_struct *tsec = current_security(); 219 220 return tsec->sid; 221 } 222 223 /* Allocate and free functions for each kind of security blob. */ 224 225 static int inode_alloc_security(struct inode *inode) 226 { 227 struct inode_security_struct *isec; 228 u32 sid = current_sid(); 229 230 isec = kmem_cache_zalloc(sel_inode_cache, GFP_NOFS); 231 if (!isec) 232 return -ENOMEM; 233 234 mutex_init(&isec->lock); 235 INIT_LIST_HEAD(&isec->list); 236 isec->inode = inode; 237 isec->sid = SECINITSID_UNLABELED; 238 isec->sclass = SECCLASS_FILE; 239 isec->task_sid = sid; 240 inode->i_security = isec; 241 242 return 0; 243 } 244 245 static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dentry); 246 247 /* 248 * Try reloading inode security labels that have been marked as invalid. The 249 * @may_sleep parameter indicates when sleeping and thus reloading labels is 250 * allowed; when set to false, returns ERR_PTR(-ECHILD) when the label is 251 * invalid. The @opt_dentry parameter should be set to a dentry of the inode; 252 * when no dentry is available, set it to NULL instead. 253 */ 254 static int __inode_security_revalidate(struct inode *inode, 255 struct dentry *opt_dentry, 256 bool may_sleep) 257 { 258 struct inode_security_struct *isec = inode->i_security; 259 260 might_sleep_if(may_sleep); 261 262 if (ss_initialized && isec->initialized != LABEL_INITIALIZED) { 263 if (!may_sleep) 264 return -ECHILD; 265 266 /* 267 * Try reloading the inode security label. This will fail if 268 * @opt_dentry is NULL and no dentry for this inode can be 269 * found; in that case, continue using the old label. 270 */ 271 inode_doinit_with_dentry(inode, opt_dentry); 272 } 273 return 0; 274 } 275 276 static struct inode_security_struct *inode_security_novalidate(struct inode *inode) 277 { 278 return inode->i_security; 279 } 280 281 static struct inode_security_struct *inode_security_rcu(struct inode *inode, bool rcu) 282 { 283 int error; 284 285 error = __inode_security_revalidate(inode, NULL, !rcu); 286 if (error) 287 return ERR_PTR(error); 288 return inode->i_security; 289 } 290 291 /* 292 * Get the security label of an inode. 293 */ 294 static struct inode_security_struct *inode_security(struct inode *inode) 295 { 296 __inode_security_revalidate(inode, NULL, true); 297 return inode->i_security; 298 } 299 300 static struct inode_security_struct *backing_inode_security_novalidate(struct dentry *dentry) 301 { 302 struct inode *inode = d_backing_inode(dentry); 303 304 return inode->i_security; 305 } 306 307 /* 308 * Get the security label of a dentry's backing inode. 309 */ 310 static struct inode_security_struct *backing_inode_security(struct dentry *dentry) 311 { 312 struct inode *inode = d_backing_inode(dentry); 313 314 __inode_security_revalidate(inode, dentry, true); 315 return inode->i_security; 316 } 317 318 static void inode_free_rcu(struct rcu_head *head) 319 { 320 struct inode_security_struct *isec; 321 322 isec = container_of(head, struct inode_security_struct, rcu); 323 kmem_cache_free(sel_inode_cache, isec); 324 } 325 326 static void inode_free_security(struct inode *inode) 327 { 328 struct inode_security_struct *isec = inode->i_security; 329 struct superblock_security_struct *sbsec = inode->i_sb->s_security; 330 331 /* 332 * As not all inode security structures are in a list, we check for 333 * empty list outside of the lock to make sure that we won't waste 334 * time taking a lock doing nothing. 335 * 336 * The list_del_init() function can be safely called more than once. 337 * It should not be possible for this function to be called with 338 * concurrent list_add(), but for better safety against future changes 339 * in the code, we use list_empty_careful() here. 340 */ 341 if (!list_empty_careful(&isec->list)) { 342 spin_lock(&sbsec->isec_lock); 343 list_del_init(&isec->list); 344 spin_unlock(&sbsec->isec_lock); 345 } 346 347 /* 348 * The inode may still be referenced in a path walk and 349 * a call to selinux_inode_permission() can be made 350 * after inode_free_security() is called. Ideally, the VFS 351 * wouldn't do this, but fixing that is a much harder 352 * job. For now, simply free the i_security via RCU, and 353 * leave the current inode->i_security pointer intact. 354 * The inode will be freed after the RCU grace period too. 355 */ 356 call_rcu(&isec->rcu, inode_free_rcu); 357 } 358 359 static int file_alloc_security(struct file *file) 360 { 361 struct file_security_struct *fsec; 362 u32 sid = current_sid(); 363 364 fsec = kmem_cache_zalloc(file_security_cache, GFP_KERNEL); 365 if (!fsec) 366 return -ENOMEM; 367 368 fsec->sid = sid; 369 fsec->fown_sid = sid; 370 file->f_security = fsec; 371 372 return 0; 373 } 374 375 static void file_free_security(struct file *file) 376 { 377 struct file_security_struct *fsec = file->f_security; 378 file->f_security = NULL; 379 kmem_cache_free(file_security_cache, fsec); 380 } 381 382 static int superblock_alloc_security(struct super_block *sb) 383 { 384 struct superblock_security_struct *sbsec; 385 386 sbsec = kzalloc(sizeof(struct superblock_security_struct), GFP_KERNEL); 387 if (!sbsec) 388 return -ENOMEM; 389 390 mutex_init(&sbsec->lock); 391 INIT_LIST_HEAD(&sbsec->isec_head); 392 spin_lock_init(&sbsec->isec_lock); 393 sbsec->sb = sb; 394 sbsec->sid = SECINITSID_UNLABELED; 395 sbsec->def_sid = SECINITSID_FILE; 396 sbsec->mntpoint_sid = SECINITSID_UNLABELED; 397 sb->s_security = sbsec; 398 399 return 0; 400 } 401 402 static void superblock_free_security(struct super_block *sb) 403 { 404 struct superblock_security_struct *sbsec = sb->s_security; 405 sb->s_security = NULL; 406 kfree(sbsec); 407 } 408 409 /* The file system's label must be initialized prior to use. */ 410 411 static const char *labeling_behaviors[7] = { 412 "uses xattr", 413 "uses transition SIDs", 414 "uses task SIDs", 415 "uses genfs_contexts", 416 "not configured for labeling", 417 "uses mountpoint labeling", 418 "uses native labeling", 419 }; 420 421 static inline int inode_doinit(struct inode *inode) 422 { 423 return inode_doinit_with_dentry(inode, NULL); 424 } 425 426 enum { 427 Opt_error = -1, 428 Opt_context = 1, 429 Opt_fscontext = 2, 430 Opt_defcontext = 3, 431 Opt_rootcontext = 4, 432 Opt_labelsupport = 5, 433 Opt_nextmntopt = 6, 434 }; 435 436 #define NUM_SEL_MNT_OPTS (Opt_nextmntopt - 1) 437 438 static const match_table_t tokens = { 439 {Opt_context, CONTEXT_STR "%s"}, 440 {Opt_fscontext, FSCONTEXT_STR "%s"}, 441 {Opt_defcontext, DEFCONTEXT_STR "%s"}, 442 {Opt_rootcontext, ROOTCONTEXT_STR "%s"}, 443 {Opt_labelsupport, LABELSUPP_STR}, 444 {Opt_error, NULL}, 445 }; 446 447 #define SEL_MOUNT_FAIL_MSG "SELinux: duplicate or incompatible mount options\n" 448 449 static int may_context_mount_sb_relabel(u32 sid, 450 struct superblock_security_struct *sbsec, 451 const struct cred *cred) 452 { 453 const struct task_security_struct *tsec = cred->security; 454 int rc; 455 456 rc = avc_has_perm(tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM, 457 FILESYSTEM__RELABELFROM, NULL); 458 if (rc) 459 return rc; 460 461 rc = avc_has_perm(tsec->sid, sid, SECCLASS_FILESYSTEM, 462 FILESYSTEM__RELABELTO, NULL); 463 return rc; 464 } 465 466 static int may_context_mount_inode_relabel(u32 sid, 467 struct superblock_security_struct *sbsec, 468 const struct cred *cred) 469 { 470 const struct task_security_struct *tsec = cred->security; 471 int rc; 472 rc = avc_has_perm(tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM, 473 FILESYSTEM__RELABELFROM, NULL); 474 if (rc) 475 return rc; 476 477 rc = avc_has_perm(sid, sbsec->sid, SECCLASS_FILESYSTEM, 478 FILESYSTEM__ASSOCIATE, NULL); 479 return rc; 480 } 481 482 static int selinux_is_sblabel_mnt(struct super_block *sb) 483 { 484 struct superblock_security_struct *sbsec = sb->s_security; 485 486 return sbsec->behavior == SECURITY_FS_USE_XATTR || 487 sbsec->behavior == SECURITY_FS_USE_TRANS || 488 sbsec->behavior == SECURITY_FS_USE_TASK || 489 sbsec->behavior == SECURITY_FS_USE_NATIVE || 490 /* Special handling. Genfs but also in-core setxattr handler */ 491 !strcmp(sb->s_type->name, "sysfs") || 492 !strcmp(sb->s_type->name, "pstore") || 493 !strcmp(sb->s_type->name, "debugfs") || 494 !strcmp(sb->s_type->name, "rootfs"); 495 } 496 497 static int sb_finish_set_opts(struct super_block *sb) 498 { 499 struct superblock_security_struct *sbsec = sb->s_security; 500 struct dentry *root = sb->s_root; 501 struct inode *root_inode = d_backing_inode(root); 502 int rc = 0; 503 504 if (sbsec->behavior == SECURITY_FS_USE_XATTR) { 505 /* Make sure that the xattr handler exists and that no 506 error other than -ENODATA is returned by getxattr on 507 the root directory. -ENODATA is ok, as this may be 508 the first boot of the SELinux kernel before we have 509 assigned xattr values to the filesystem. */ 510 if (!root_inode->i_op->getxattr) { 511 printk(KERN_WARNING "SELinux: (dev %s, type %s) has no " 512 "xattr support\n", sb->s_id, sb->s_type->name); 513 rc = -EOPNOTSUPP; 514 goto out; 515 } 516 rc = root_inode->i_op->getxattr(root, root_inode, 517 XATTR_NAME_SELINUX, NULL, 0); 518 if (rc < 0 && rc != -ENODATA) { 519 if (rc == -EOPNOTSUPP) 520 printk(KERN_WARNING "SELinux: (dev %s, type " 521 "%s) has no security xattr handler\n", 522 sb->s_id, sb->s_type->name); 523 else 524 printk(KERN_WARNING "SELinux: (dev %s, type " 525 "%s) getxattr errno %d\n", sb->s_id, 526 sb->s_type->name, -rc); 527 goto out; 528 } 529 } 530 531 if (sbsec->behavior > ARRAY_SIZE(labeling_behaviors)) 532 printk(KERN_ERR "SELinux: initialized (dev %s, type %s), unknown behavior\n", 533 sb->s_id, sb->s_type->name); 534 535 sbsec->flags |= SE_SBINITIALIZED; 536 if (selinux_is_sblabel_mnt(sb)) 537 sbsec->flags |= SBLABEL_MNT; 538 539 /* Initialize the root inode. */ 540 rc = inode_doinit_with_dentry(root_inode, root); 541 542 /* Initialize any other inodes associated with the superblock, e.g. 543 inodes created prior to initial policy load or inodes created 544 during get_sb by a pseudo filesystem that directly 545 populates itself. */ 546 spin_lock(&sbsec->isec_lock); 547 next_inode: 548 if (!list_empty(&sbsec->isec_head)) { 549 struct inode_security_struct *isec = 550 list_entry(sbsec->isec_head.next, 551 struct inode_security_struct, list); 552 struct inode *inode = isec->inode; 553 list_del_init(&isec->list); 554 spin_unlock(&sbsec->isec_lock); 555 inode = igrab(inode); 556 if (inode) { 557 if (!IS_PRIVATE(inode)) 558 inode_doinit(inode); 559 iput(inode); 560 } 561 spin_lock(&sbsec->isec_lock); 562 goto next_inode; 563 } 564 spin_unlock(&sbsec->isec_lock); 565 out: 566 return rc; 567 } 568 569 /* 570 * This function should allow an FS to ask what it's mount security 571 * options were so it can use those later for submounts, displaying 572 * mount options, or whatever. 573 */ 574 static int selinux_get_mnt_opts(const struct super_block *sb, 575 struct security_mnt_opts *opts) 576 { 577 int rc = 0, i; 578 struct superblock_security_struct *sbsec = sb->s_security; 579 char *context = NULL; 580 u32 len; 581 char tmp; 582 583 security_init_mnt_opts(opts); 584 585 if (!(sbsec->flags & SE_SBINITIALIZED)) 586 return -EINVAL; 587 588 if (!ss_initialized) 589 return -EINVAL; 590 591 /* make sure we always check enough bits to cover the mask */ 592 BUILD_BUG_ON(SE_MNTMASK >= (1 << NUM_SEL_MNT_OPTS)); 593 594 tmp = sbsec->flags & SE_MNTMASK; 595 /* count the number of mount options for this sb */ 596 for (i = 0; i < NUM_SEL_MNT_OPTS; i++) { 597 if (tmp & 0x01) 598 opts->num_mnt_opts++; 599 tmp >>= 1; 600 } 601 /* Check if the Label support flag is set */ 602 if (sbsec->flags & SBLABEL_MNT) 603 opts->num_mnt_opts++; 604 605 opts->mnt_opts = kcalloc(opts->num_mnt_opts, sizeof(char *), GFP_ATOMIC); 606 if (!opts->mnt_opts) { 607 rc = -ENOMEM; 608 goto out_free; 609 } 610 611 opts->mnt_opts_flags = kcalloc(opts->num_mnt_opts, sizeof(int), GFP_ATOMIC); 612 if (!opts->mnt_opts_flags) { 613 rc = -ENOMEM; 614 goto out_free; 615 } 616 617 i = 0; 618 if (sbsec->flags & FSCONTEXT_MNT) { 619 rc = security_sid_to_context(sbsec->sid, &context, &len); 620 if (rc) 621 goto out_free; 622 opts->mnt_opts[i] = context; 623 opts->mnt_opts_flags[i++] = FSCONTEXT_MNT; 624 } 625 if (sbsec->flags & CONTEXT_MNT) { 626 rc = security_sid_to_context(sbsec->mntpoint_sid, &context, &len); 627 if (rc) 628 goto out_free; 629 opts->mnt_opts[i] = context; 630 opts->mnt_opts_flags[i++] = CONTEXT_MNT; 631 } 632 if (sbsec->flags & DEFCONTEXT_MNT) { 633 rc = security_sid_to_context(sbsec->def_sid, &context, &len); 634 if (rc) 635 goto out_free; 636 opts->mnt_opts[i] = context; 637 opts->mnt_opts_flags[i++] = DEFCONTEXT_MNT; 638 } 639 if (sbsec->flags & ROOTCONTEXT_MNT) { 640 struct dentry *root = sbsec->sb->s_root; 641 struct inode_security_struct *isec = backing_inode_security(root); 642 643 rc = security_sid_to_context(isec->sid, &context, &len); 644 if (rc) 645 goto out_free; 646 opts->mnt_opts[i] = context; 647 opts->mnt_opts_flags[i++] = ROOTCONTEXT_MNT; 648 } 649 if (sbsec->flags & SBLABEL_MNT) { 650 opts->mnt_opts[i] = NULL; 651 opts->mnt_opts_flags[i++] = SBLABEL_MNT; 652 } 653 654 BUG_ON(i != opts->num_mnt_opts); 655 656 return 0; 657 658 out_free: 659 security_free_mnt_opts(opts); 660 return rc; 661 } 662 663 static int bad_option(struct superblock_security_struct *sbsec, char flag, 664 u32 old_sid, u32 new_sid) 665 { 666 char mnt_flags = sbsec->flags & SE_MNTMASK; 667 668 /* check if the old mount command had the same options */ 669 if (sbsec->flags & SE_SBINITIALIZED) 670 if (!(sbsec->flags & flag) || 671 (old_sid != new_sid)) 672 return 1; 673 674 /* check if we were passed the same options twice, 675 * aka someone passed context=a,context=b 676 */ 677 if (!(sbsec->flags & SE_SBINITIALIZED)) 678 if (mnt_flags & flag) 679 return 1; 680 return 0; 681 } 682 683 /* 684 * Allow filesystems with binary mount data to explicitly set mount point 685 * labeling information. 686 */ 687 static int selinux_set_mnt_opts(struct super_block *sb, 688 struct security_mnt_opts *opts, 689 unsigned long kern_flags, 690 unsigned long *set_kern_flags) 691 { 692 const struct cred *cred = current_cred(); 693 int rc = 0, i; 694 struct superblock_security_struct *sbsec = sb->s_security; 695 const char *name = sb->s_type->name; 696 struct dentry *root = sbsec->sb->s_root; 697 struct inode_security_struct *root_isec; 698 u32 fscontext_sid = 0, context_sid = 0, rootcontext_sid = 0; 699 u32 defcontext_sid = 0; 700 char **mount_options = opts->mnt_opts; 701 int *flags = opts->mnt_opts_flags; 702 int num_opts = opts->num_mnt_opts; 703 704 mutex_lock(&sbsec->lock); 705 706 if (!ss_initialized) { 707 if (!num_opts) { 708 /* Defer initialization until selinux_complete_init, 709 after the initial policy is loaded and the security 710 server is ready to handle calls. */ 711 goto out; 712 } 713 rc = -EINVAL; 714 printk(KERN_WARNING "SELinux: Unable to set superblock options " 715 "before the security server is initialized\n"); 716 goto out; 717 } 718 if (kern_flags && !set_kern_flags) { 719 /* Specifying internal flags without providing a place to 720 * place the results is not allowed */ 721 rc = -EINVAL; 722 goto out; 723 } 724 725 /* 726 * Binary mount data FS will come through this function twice. Once 727 * from an explicit call and once from the generic calls from the vfs. 728 * Since the generic VFS calls will not contain any security mount data 729 * we need to skip the double mount verification. 730 * 731 * This does open a hole in which we will not notice if the first 732 * mount using this sb set explict options and a second mount using 733 * this sb does not set any security options. (The first options 734 * will be used for both mounts) 735 */ 736 if ((sbsec->flags & SE_SBINITIALIZED) && (sb->s_type->fs_flags & FS_BINARY_MOUNTDATA) 737 && (num_opts == 0)) 738 goto out; 739 740 root_isec = backing_inode_security_novalidate(root); 741 742 /* 743 * parse the mount options, check if they are valid sids. 744 * also check if someone is trying to mount the same sb more 745 * than once with different security options. 746 */ 747 for (i = 0; i < num_opts; i++) { 748 u32 sid; 749 750 if (flags[i] == SBLABEL_MNT) 751 continue; 752 rc = security_context_str_to_sid(mount_options[i], &sid, GFP_KERNEL); 753 if (rc) { 754 printk(KERN_WARNING "SELinux: security_context_str_to_sid" 755 "(%s) failed for (dev %s, type %s) errno=%d\n", 756 mount_options[i], sb->s_id, name, rc); 757 goto out; 758 } 759 switch (flags[i]) { 760 case FSCONTEXT_MNT: 761 fscontext_sid = sid; 762 763 if (bad_option(sbsec, FSCONTEXT_MNT, sbsec->sid, 764 fscontext_sid)) 765 goto out_double_mount; 766 767 sbsec->flags |= FSCONTEXT_MNT; 768 break; 769 case CONTEXT_MNT: 770 context_sid = sid; 771 772 if (bad_option(sbsec, CONTEXT_MNT, sbsec->mntpoint_sid, 773 context_sid)) 774 goto out_double_mount; 775 776 sbsec->flags |= CONTEXT_MNT; 777 break; 778 case ROOTCONTEXT_MNT: 779 rootcontext_sid = sid; 780 781 if (bad_option(sbsec, ROOTCONTEXT_MNT, root_isec->sid, 782 rootcontext_sid)) 783 goto out_double_mount; 784 785 sbsec->flags |= ROOTCONTEXT_MNT; 786 787 break; 788 case DEFCONTEXT_MNT: 789 defcontext_sid = sid; 790 791 if (bad_option(sbsec, DEFCONTEXT_MNT, sbsec->def_sid, 792 defcontext_sid)) 793 goto out_double_mount; 794 795 sbsec->flags |= DEFCONTEXT_MNT; 796 797 break; 798 default: 799 rc = -EINVAL; 800 goto out; 801 } 802 } 803 804 if (sbsec->flags & SE_SBINITIALIZED) { 805 /* previously mounted with options, but not on this attempt? */ 806 if ((sbsec->flags & SE_MNTMASK) && !num_opts) 807 goto out_double_mount; 808 rc = 0; 809 goto out; 810 } 811 812 if (strcmp(sb->s_type->name, "proc") == 0) 813 sbsec->flags |= SE_SBPROC | SE_SBGENFS; 814 815 if (!strcmp(sb->s_type->name, "debugfs") || 816 !strcmp(sb->s_type->name, "sysfs") || 817 !strcmp(sb->s_type->name, "pstore")) 818 sbsec->flags |= SE_SBGENFS; 819 820 if (!sbsec->behavior) { 821 /* 822 * Determine the labeling behavior to use for this 823 * filesystem type. 824 */ 825 rc = security_fs_use(sb); 826 if (rc) { 827 printk(KERN_WARNING 828 "%s: security_fs_use(%s) returned %d\n", 829 __func__, sb->s_type->name, rc); 830 goto out; 831 } 832 } 833 834 /* 835 * If this is a user namespace mount, no contexts are allowed 836 * on the command line and security labels must be ignored. 837 */ 838 if (sb->s_user_ns != &init_user_ns) { 839 if (context_sid || fscontext_sid || rootcontext_sid || 840 defcontext_sid) { 841 rc = -EACCES; 842 goto out; 843 } 844 if (sbsec->behavior == SECURITY_FS_USE_XATTR) { 845 sbsec->behavior = SECURITY_FS_USE_MNTPOINT; 846 rc = security_transition_sid(current_sid(), current_sid(), 847 SECCLASS_FILE, NULL, 848 &sbsec->mntpoint_sid); 849 if (rc) 850 goto out; 851 } 852 goto out_set_opts; 853 } 854 855 /* sets the context of the superblock for the fs being mounted. */ 856 if (fscontext_sid) { 857 rc = may_context_mount_sb_relabel(fscontext_sid, sbsec, cred); 858 if (rc) 859 goto out; 860 861 sbsec->sid = fscontext_sid; 862 } 863 864 /* 865 * Switch to using mount point labeling behavior. 866 * sets the label used on all file below the mountpoint, and will set 867 * the superblock context if not already set. 868 */ 869 if (kern_flags & SECURITY_LSM_NATIVE_LABELS && !context_sid) { 870 sbsec->behavior = SECURITY_FS_USE_NATIVE; 871 *set_kern_flags |= SECURITY_LSM_NATIVE_LABELS; 872 } 873 874 if (context_sid) { 875 if (!fscontext_sid) { 876 rc = may_context_mount_sb_relabel(context_sid, sbsec, 877 cred); 878 if (rc) 879 goto out; 880 sbsec->sid = context_sid; 881 } else { 882 rc = may_context_mount_inode_relabel(context_sid, sbsec, 883 cred); 884 if (rc) 885 goto out; 886 } 887 if (!rootcontext_sid) 888 rootcontext_sid = context_sid; 889 890 sbsec->mntpoint_sid = context_sid; 891 sbsec->behavior = SECURITY_FS_USE_MNTPOINT; 892 } 893 894 if (rootcontext_sid) { 895 rc = may_context_mount_inode_relabel(rootcontext_sid, sbsec, 896 cred); 897 if (rc) 898 goto out; 899 900 root_isec->sid = rootcontext_sid; 901 root_isec->initialized = LABEL_INITIALIZED; 902 } 903 904 if (defcontext_sid) { 905 if (sbsec->behavior != SECURITY_FS_USE_XATTR && 906 sbsec->behavior != SECURITY_FS_USE_NATIVE) { 907 rc = -EINVAL; 908 printk(KERN_WARNING "SELinux: defcontext option is " 909 "invalid for this filesystem type\n"); 910 goto out; 911 } 912 913 if (defcontext_sid != sbsec->def_sid) { 914 rc = may_context_mount_inode_relabel(defcontext_sid, 915 sbsec, cred); 916 if (rc) 917 goto out; 918 } 919 920 sbsec->def_sid = defcontext_sid; 921 } 922 923 out_set_opts: 924 rc = sb_finish_set_opts(sb); 925 out: 926 mutex_unlock(&sbsec->lock); 927 return rc; 928 out_double_mount: 929 rc = -EINVAL; 930 printk(KERN_WARNING "SELinux: mount invalid. Same superblock, different " 931 "security settings for (dev %s, type %s)\n", sb->s_id, name); 932 goto out; 933 } 934 935 static int selinux_cmp_sb_context(const struct super_block *oldsb, 936 const struct super_block *newsb) 937 { 938 struct superblock_security_struct *old = oldsb->s_security; 939 struct superblock_security_struct *new = newsb->s_security; 940 char oldflags = old->flags & SE_MNTMASK; 941 char newflags = new->flags & SE_MNTMASK; 942 943 if (oldflags != newflags) 944 goto mismatch; 945 if ((oldflags & FSCONTEXT_MNT) && old->sid != new->sid) 946 goto mismatch; 947 if ((oldflags & CONTEXT_MNT) && old->mntpoint_sid != new->mntpoint_sid) 948 goto mismatch; 949 if ((oldflags & DEFCONTEXT_MNT) && old->def_sid != new->def_sid) 950 goto mismatch; 951 if (oldflags & ROOTCONTEXT_MNT) { 952 struct inode_security_struct *oldroot = backing_inode_security(oldsb->s_root); 953 struct inode_security_struct *newroot = backing_inode_security(newsb->s_root); 954 if (oldroot->sid != newroot->sid) 955 goto mismatch; 956 } 957 return 0; 958 mismatch: 959 printk(KERN_WARNING "SELinux: mount invalid. Same superblock, " 960 "different security settings for (dev %s, " 961 "type %s)\n", newsb->s_id, newsb->s_type->name); 962 return -EBUSY; 963 } 964 965 static int selinux_sb_clone_mnt_opts(const struct super_block *oldsb, 966 struct super_block *newsb) 967 { 968 const struct superblock_security_struct *oldsbsec = oldsb->s_security; 969 struct superblock_security_struct *newsbsec = newsb->s_security; 970 971 int set_fscontext = (oldsbsec->flags & FSCONTEXT_MNT); 972 int set_context = (oldsbsec->flags & CONTEXT_MNT); 973 int set_rootcontext = (oldsbsec->flags & ROOTCONTEXT_MNT); 974 975 /* 976 * if the parent was able to be mounted it clearly had no special lsm 977 * mount options. thus we can safely deal with this superblock later 978 */ 979 if (!ss_initialized) 980 return 0; 981 982 /* how can we clone if the old one wasn't set up?? */ 983 BUG_ON(!(oldsbsec->flags & SE_SBINITIALIZED)); 984 985 /* if fs is reusing a sb, make sure that the contexts match */ 986 if (newsbsec->flags & SE_SBINITIALIZED) 987 return selinux_cmp_sb_context(oldsb, newsb); 988 989 mutex_lock(&newsbsec->lock); 990 991 newsbsec->flags = oldsbsec->flags; 992 993 newsbsec->sid = oldsbsec->sid; 994 newsbsec->def_sid = oldsbsec->def_sid; 995 newsbsec->behavior = oldsbsec->behavior; 996 997 if (set_context) { 998 u32 sid = oldsbsec->mntpoint_sid; 999 1000 if (!set_fscontext) 1001 newsbsec->sid = sid; 1002 if (!set_rootcontext) { 1003 struct inode_security_struct *newisec = backing_inode_security(newsb->s_root); 1004 newisec->sid = sid; 1005 } 1006 newsbsec->mntpoint_sid = sid; 1007 } 1008 if (set_rootcontext) { 1009 const struct inode_security_struct *oldisec = backing_inode_security(oldsb->s_root); 1010 struct inode_security_struct *newisec = backing_inode_security(newsb->s_root); 1011 1012 newisec->sid = oldisec->sid; 1013 } 1014 1015 sb_finish_set_opts(newsb); 1016 mutex_unlock(&newsbsec->lock); 1017 return 0; 1018 } 1019 1020 static int selinux_parse_opts_str(char *options, 1021 struct security_mnt_opts *opts) 1022 { 1023 char *p; 1024 char *context = NULL, *defcontext = NULL; 1025 char *fscontext = NULL, *rootcontext = NULL; 1026 int rc, num_mnt_opts = 0; 1027 1028 opts->num_mnt_opts = 0; 1029 1030 /* Standard string-based options. */ 1031 while ((p = strsep(&options, "|")) != NULL) { 1032 int token; 1033 substring_t args[MAX_OPT_ARGS]; 1034 1035 if (!*p) 1036 continue; 1037 1038 token = match_token(p, tokens, args); 1039 1040 switch (token) { 1041 case Opt_context: 1042 if (context || defcontext) { 1043 rc = -EINVAL; 1044 printk(KERN_WARNING SEL_MOUNT_FAIL_MSG); 1045 goto out_err; 1046 } 1047 context = match_strdup(&args[0]); 1048 if (!context) { 1049 rc = -ENOMEM; 1050 goto out_err; 1051 } 1052 break; 1053 1054 case Opt_fscontext: 1055 if (fscontext) { 1056 rc = -EINVAL; 1057 printk(KERN_WARNING SEL_MOUNT_FAIL_MSG); 1058 goto out_err; 1059 } 1060 fscontext = match_strdup(&args[0]); 1061 if (!fscontext) { 1062 rc = -ENOMEM; 1063 goto out_err; 1064 } 1065 break; 1066 1067 case Opt_rootcontext: 1068 if (rootcontext) { 1069 rc = -EINVAL; 1070 printk(KERN_WARNING SEL_MOUNT_FAIL_MSG); 1071 goto out_err; 1072 } 1073 rootcontext = match_strdup(&args[0]); 1074 if (!rootcontext) { 1075 rc = -ENOMEM; 1076 goto out_err; 1077 } 1078 break; 1079 1080 case Opt_defcontext: 1081 if (context || defcontext) { 1082 rc = -EINVAL; 1083 printk(KERN_WARNING SEL_MOUNT_FAIL_MSG); 1084 goto out_err; 1085 } 1086 defcontext = match_strdup(&args[0]); 1087 if (!defcontext) { 1088 rc = -ENOMEM; 1089 goto out_err; 1090 } 1091 break; 1092 case Opt_labelsupport: 1093 break; 1094 default: 1095 rc = -EINVAL; 1096 printk(KERN_WARNING "SELinux: unknown mount option\n"); 1097 goto out_err; 1098 1099 } 1100 } 1101 1102 rc = -ENOMEM; 1103 opts->mnt_opts = kcalloc(NUM_SEL_MNT_OPTS, sizeof(char *), GFP_ATOMIC); 1104 if (!opts->mnt_opts) 1105 goto out_err; 1106 1107 opts->mnt_opts_flags = kcalloc(NUM_SEL_MNT_OPTS, sizeof(int), GFP_ATOMIC); 1108 if (!opts->mnt_opts_flags) { 1109 kfree(opts->mnt_opts); 1110 goto out_err; 1111 } 1112 1113 if (fscontext) { 1114 opts->mnt_opts[num_mnt_opts] = fscontext; 1115 opts->mnt_opts_flags[num_mnt_opts++] = FSCONTEXT_MNT; 1116 } 1117 if (context) { 1118 opts->mnt_opts[num_mnt_opts] = context; 1119 opts->mnt_opts_flags[num_mnt_opts++] = CONTEXT_MNT; 1120 } 1121 if (rootcontext) { 1122 opts->mnt_opts[num_mnt_opts] = rootcontext; 1123 opts->mnt_opts_flags[num_mnt_opts++] = ROOTCONTEXT_MNT; 1124 } 1125 if (defcontext) { 1126 opts->mnt_opts[num_mnt_opts] = defcontext; 1127 opts->mnt_opts_flags[num_mnt_opts++] = DEFCONTEXT_MNT; 1128 } 1129 1130 opts->num_mnt_opts = num_mnt_opts; 1131 return 0; 1132 1133 out_err: 1134 kfree(context); 1135 kfree(defcontext); 1136 kfree(fscontext); 1137 kfree(rootcontext); 1138 return rc; 1139 } 1140 /* 1141 * string mount options parsing and call set the sbsec 1142 */ 1143 static int superblock_doinit(struct super_block *sb, void *data) 1144 { 1145 int rc = 0; 1146 char *options = data; 1147 struct security_mnt_opts opts; 1148 1149 security_init_mnt_opts(&opts); 1150 1151 if (!data) 1152 goto out; 1153 1154 BUG_ON(sb->s_type->fs_flags & FS_BINARY_MOUNTDATA); 1155 1156 rc = selinux_parse_opts_str(options, &opts); 1157 if (rc) 1158 goto out_err; 1159 1160 out: 1161 rc = selinux_set_mnt_opts(sb, &opts, 0, NULL); 1162 1163 out_err: 1164 security_free_mnt_opts(&opts); 1165 return rc; 1166 } 1167 1168 static void selinux_write_opts(struct seq_file *m, 1169 struct security_mnt_opts *opts) 1170 { 1171 int i; 1172 char *prefix; 1173 1174 for (i = 0; i < opts->num_mnt_opts; i++) { 1175 char *has_comma; 1176 1177 if (opts->mnt_opts[i]) 1178 has_comma = strchr(opts->mnt_opts[i], ','); 1179 else 1180 has_comma = NULL; 1181 1182 switch (opts->mnt_opts_flags[i]) { 1183 case CONTEXT_MNT: 1184 prefix = CONTEXT_STR; 1185 break; 1186 case FSCONTEXT_MNT: 1187 prefix = FSCONTEXT_STR; 1188 break; 1189 case ROOTCONTEXT_MNT: 1190 prefix = ROOTCONTEXT_STR; 1191 break; 1192 case DEFCONTEXT_MNT: 1193 prefix = DEFCONTEXT_STR; 1194 break; 1195 case SBLABEL_MNT: 1196 seq_putc(m, ','); 1197 seq_puts(m, LABELSUPP_STR); 1198 continue; 1199 default: 1200 BUG(); 1201 return; 1202 }; 1203 /* we need a comma before each option */ 1204 seq_putc(m, ','); 1205 seq_puts(m, prefix); 1206 if (has_comma) 1207 seq_putc(m, '\"'); 1208 seq_escape(m, opts->mnt_opts[i], "\"\n\\"); 1209 if (has_comma) 1210 seq_putc(m, '\"'); 1211 } 1212 } 1213 1214 static int selinux_sb_show_options(struct seq_file *m, struct super_block *sb) 1215 { 1216 struct security_mnt_opts opts; 1217 int rc; 1218 1219 rc = selinux_get_mnt_opts(sb, &opts); 1220 if (rc) { 1221 /* before policy load we may get EINVAL, don't show anything */ 1222 if (rc == -EINVAL) 1223 rc = 0; 1224 return rc; 1225 } 1226 1227 selinux_write_opts(m, &opts); 1228 1229 security_free_mnt_opts(&opts); 1230 1231 return rc; 1232 } 1233 1234 static inline u16 inode_mode_to_security_class(umode_t mode) 1235 { 1236 switch (mode & S_IFMT) { 1237 case S_IFSOCK: 1238 return SECCLASS_SOCK_FILE; 1239 case S_IFLNK: 1240 return SECCLASS_LNK_FILE; 1241 case S_IFREG: 1242 return SECCLASS_FILE; 1243 case S_IFBLK: 1244 return SECCLASS_BLK_FILE; 1245 case S_IFDIR: 1246 return SECCLASS_DIR; 1247 case S_IFCHR: 1248 return SECCLASS_CHR_FILE; 1249 case S_IFIFO: 1250 return SECCLASS_FIFO_FILE; 1251 1252 } 1253 1254 return SECCLASS_FILE; 1255 } 1256 1257 static inline int default_protocol_stream(int protocol) 1258 { 1259 return (protocol == IPPROTO_IP || protocol == IPPROTO_TCP); 1260 } 1261 1262 static inline int default_protocol_dgram(int protocol) 1263 { 1264 return (protocol == IPPROTO_IP || protocol == IPPROTO_UDP); 1265 } 1266 1267 static inline u16 socket_type_to_security_class(int family, int type, int protocol) 1268 { 1269 switch (family) { 1270 case PF_UNIX: 1271 switch (type) { 1272 case SOCK_STREAM: 1273 case SOCK_SEQPACKET: 1274 return SECCLASS_UNIX_STREAM_SOCKET; 1275 case SOCK_DGRAM: 1276 return SECCLASS_UNIX_DGRAM_SOCKET; 1277 } 1278 break; 1279 case PF_INET: 1280 case PF_INET6: 1281 switch (type) { 1282 case SOCK_STREAM: 1283 if (default_protocol_stream(protocol)) 1284 return SECCLASS_TCP_SOCKET; 1285 else 1286 return SECCLASS_RAWIP_SOCKET; 1287 case SOCK_DGRAM: 1288 if (default_protocol_dgram(protocol)) 1289 return SECCLASS_UDP_SOCKET; 1290 else 1291 return SECCLASS_RAWIP_SOCKET; 1292 case SOCK_DCCP: 1293 return SECCLASS_DCCP_SOCKET; 1294 default: 1295 return SECCLASS_RAWIP_SOCKET; 1296 } 1297 break; 1298 case PF_NETLINK: 1299 switch (protocol) { 1300 case NETLINK_ROUTE: 1301 return SECCLASS_NETLINK_ROUTE_SOCKET; 1302 case NETLINK_SOCK_DIAG: 1303 return SECCLASS_NETLINK_TCPDIAG_SOCKET; 1304 case NETLINK_NFLOG: 1305 return SECCLASS_NETLINK_NFLOG_SOCKET; 1306 case NETLINK_XFRM: 1307 return SECCLASS_NETLINK_XFRM_SOCKET; 1308 case NETLINK_SELINUX: 1309 return SECCLASS_NETLINK_SELINUX_SOCKET; 1310 case NETLINK_ISCSI: 1311 return SECCLASS_NETLINK_ISCSI_SOCKET; 1312 case NETLINK_AUDIT: 1313 return SECCLASS_NETLINK_AUDIT_SOCKET; 1314 case NETLINK_FIB_LOOKUP: 1315 return SECCLASS_NETLINK_FIB_LOOKUP_SOCKET; 1316 case NETLINK_CONNECTOR: 1317 return SECCLASS_NETLINK_CONNECTOR_SOCKET; 1318 case NETLINK_NETFILTER: 1319 return SECCLASS_NETLINK_NETFILTER_SOCKET; 1320 case NETLINK_DNRTMSG: 1321 return SECCLASS_NETLINK_DNRT_SOCKET; 1322 case NETLINK_KOBJECT_UEVENT: 1323 return SECCLASS_NETLINK_KOBJECT_UEVENT_SOCKET; 1324 case NETLINK_GENERIC: 1325 return SECCLASS_NETLINK_GENERIC_SOCKET; 1326 case NETLINK_SCSITRANSPORT: 1327 return SECCLASS_NETLINK_SCSITRANSPORT_SOCKET; 1328 case NETLINK_RDMA: 1329 return SECCLASS_NETLINK_RDMA_SOCKET; 1330 case NETLINK_CRYPTO: 1331 return SECCLASS_NETLINK_CRYPTO_SOCKET; 1332 default: 1333 return SECCLASS_NETLINK_SOCKET; 1334 } 1335 case PF_PACKET: 1336 return SECCLASS_PACKET_SOCKET; 1337 case PF_KEY: 1338 return SECCLASS_KEY_SOCKET; 1339 case PF_APPLETALK: 1340 return SECCLASS_APPLETALK_SOCKET; 1341 } 1342 1343 return SECCLASS_SOCKET; 1344 } 1345 1346 static int selinux_genfs_get_sid(struct dentry *dentry, 1347 u16 tclass, 1348 u16 flags, 1349 u32 *sid) 1350 { 1351 int rc; 1352 struct super_block *sb = dentry->d_sb; 1353 char *buffer, *path; 1354 1355 buffer = (char *)__get_free_page(GFP_KERNEL); 1356 if (!buffer) 1357 return -ENOMEM; 1358 1359 path = dentry_path_raw(dentry, buffer, PAGE_SIZE); 1360 if (IS_ERR(path)) 1361 rc = PTR_ERR(path); 1362 else { 1363 if (flags & SE_SBPROC) { 1364 /* each process gets a /proc/PID/ entry. Strip off the 1365 * PID part to get a valid selinux labeling. 1366 * e.g. /proc/1/net/rpc/nfs -> /net/rpc/nfs */ 1367 while (path[1] >= '0' && path[1] <= '9') { 1368 path[1] = '/'; 1369 path++; 1370 } 1371 } 1372 rc = security_genfs_sid(sb->s_type->name, path, tclass, sid); 1373 } 1374 free_page((unsigned long)buffer); 1375 return rc; 1376 } 1377 1378 /* The inode's security attributes must be initialized before first use. */ 1379 static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dentry) 1380 { 1381 struct superblock_security_struct *sbsec = NULL; 1382 struct inode_security_struct *isec = inode->i_security; 1383 u32 sid; 1384 struct dentry *dentry; 1385 #define INITCONTEXTLEN 255 1386 char *context = NULL; 1387 unsigned len = 0; 1388 int rc = 0; 1389 1390 if (isec->initialized == LABEL_INITIALIZED) 1391 goto out; 1392 1393 mutex_lock(&isec->lock); 1394 if (isec->initialized == LABEL_INITIALIZED) 1395 goto out_unlock; 1396 1397 sbsec = inode->i_sb->s_security; 1398 if (!(sbsec->flags & SE_SBINITIALIZED)) { 1399 /* Defer initialization until selinux_complete_init, 1400 after the initial policy is loaded and the security 1401 server is ready to handle calls. */ 1402 spin_lock(&sbsec->isec_lock); 1403 if (list_empty(&isec->list)) 1404 list_add(&isec->list, &sbsec->isec_head); 1405 spin_unlock(&sbsec->isec_lock); 1406 goto out_unlock; 1407 } 1408 1409 switch (sbsec->behavior) { 1410 case SECURITY_FS_USE_NATIVE: 1411 break; 1412 case SECURITY_FS_USE_XATTR: 1413 if (!inode->i_op->getxattr) { 1414 isec->sid = sbsec->def_sid; 1415 break; 1416 } 1417 1418 /* Need a dentry, since the xattr API requires one. 1419 Life would be simpler if we could just pass the inode. */ 1420 if (opt_dentry) { 1421 /* Called from d_instantiate or d_splice_alias. */ 1422 dentry = dget(opt_dentry); 1423 } else { 1424 /* Called from selinux_complete_init, try to find a dentry. */ 1425 dentry = d_find_alias(inode); 1426 } 1427 if (!dentry) { 1428 /* 1429 * this is can be hit on boot when a file is accessed 1430 * before the policy is loaded. When we load policy we 1431 * may find inodes that have no dentry on the 1432 * sbsec->isec_head list. No reason to complain as these 1433 * will get fixed up the next time we go through 1434 * inode_doinit with a dentry, before these inodes could 1435 * be used again by userspace. 1436 */ 1437 goto out_unlock; 1438 } 1439 1440 len = INITCONTEXTLEN; 1441 context = kmalloc(len+1, GFP_NOFS); 1442 if (!context) { 1443 rc = -ENOMEM; 1444 dput(dentry); 1445 goto out_unlock; 1446 } 1447 context[len] = '\0'; 1448 rc = inode->i_op->getxattr(dentry, inode, XATTR_NAME_SELINUX, 1449 context, len); 1450 if (rc == -ERANGE) { 1451 kfree(context); 1452 1453 /* Need a larger buffer. Query for the right size. */ 1454 rc = inode->i_op->getxattr(dentry, inode, XATTR_NAME_SELINUX, 1455 NULL, 0); 1456 if (rc < 0) { 1457 dput(dentry); 1458 goto out_unlock; 1459 } 1460 len = rc; 1461 context = kmalloc(len+1, GFP_NOFS); 1462 if (!context) { 1463 rc = -ENOMEM; 1464 dput(dentry); 1465 goto out_unlock; 1466 } 1467 context[len] = '\0'; 1468 rc = inode->i_op->getxattr(dentry, inode, 1469 XATTR_NAME_SELINUX, 1470 context, len); 1471 } 1472 dput(dentry); 1473 if (rc < 0) { 1474 if (rc != -ENODATA) { 1475 printk(KERN_WARNING "SELinux: %s: getxattr returned " 1476 "%d for dev=%s ino=%ld\n", __func__, 1477 -rc, inode->i_sb->s_id, inode->i_ino); 1478 kfree(context); 1479 goto out_unlock; 1480 } 1481 /* Map ENODATA to the default file SID */ 1482 sid = sbsec->def_sid; 1483 rc = 0; 1484 } else { 1485 rc = security_context_to_sid_default(context, rc, &sid, 1486 sbsec->def_sid, 1487 GFP_NOFS); 1488 if (rc) { 1489 char *dev = inode->i_sb->s_id; 1490 unsigned long ino = inode->i_ino; 1491 1492 if (rc == -EINVAL) { 1493 if (printk_ratelimit()) 1494 printk(KERN_NOTICE "SELinux: inode=%lu on dev=%s was found to have an invalid " 1495 "context=%s. This indicates you may need to relabel the inode or the " 1496 "filesystem in question.\n", ino, dev, context); 1497 } else { 1498 printk(KERN_WARNING "SELinux: %s: context_to_sid(%s) " 1499 "returned %d for dev=%s ino=%ld\n", 1500 __func__, context, -rc, dev, ino); 1501 } 1502 kfree(context); 1503 /* Leave with the unlabeled SID */ 1504 rc = 0; 1505 break; 1506 } 1507 } 1508 kfree(context); 1509 isec->sid = sid; 1510 break; 1511 case SECURITY_FS_USE_TASK: 1512 isec->sid = isec->task_sid; 1513 break; 1514 case SECURITY_FS_USE_TRANS: 1515 /* Default to the fs SID. */ 1516 isec->sid = sbsec->sid; 1517 1518 /* Try to obtain a transition SID. */ 1519 isec->sclass = inode_mode_to_security_class(inode->i_mode); 1520 rc = security_transition_sid(isec->task_sid, sbsec->sid, 1521 isec->sclass, NULL, &sid); 1522 if (rc) 1523 goto out_unlock; 1524 isec->sid = sid; 1525 break; 1526 case SECURITY_FS_USE_MNTPOINT: 1527 isec->sid = sbsec->mntpoint_sid; 1528 break; 1529 default: 1530 /* Default to the fs superblock SID. */ 1531 isec->sid = sbsec->sid; 1532 1533 if ((sbsec->flags & SE_SBGENFS) && !S_ISLNK(inode->i_mode)) { 1534 /* We must have a dentry to determine the label on 1535 * procfs inodes */ 1536 if (opt_dentry) 1537 /* Called from d_instantiate or 1538 * d_splice_alias. */ 1539 dentry = dget(opt_dentry); 1540 else 1541 /* Called from selinux_complete_init, try to 1542 * find a dentry. */ 1543 dentry = d_find_alias(inode); 1544 /* 1545 * This can be hit on boot when a file is accessed 1546 * before the policy is loaded. When we load policy we 1547 * may find inodes that have no dentry on the 1548 * sbsec->isec_head list. No reason to complain as 1549 * these will get fixed up the next time we go through 1550 * inode_doinit() with a dentry, before these inodes 1551 * could be used again by userspace. 1552 */ 1553 if (!dentry) 1554 goto out_unlock; 1555 isec->sclass = inode_mode_to_security_class(inode->i_mode); 1556 rc = selinux_genfs_get_sid(dentry, isec->sclass, 1557 sbsec->flags, &sid); 1558 dput(dentry); 1559 if (rc) 1560 goto out_unlock; 1561 isec->sid = sid; 1562 } 1563 break; 1564 } 1565 1566 isec->initialized = LABEL_INITIALIZED; 1567 1568 out_unlock: 1569 mutex_unlock(&isec->lock); 1570 out: 1571 if (isec->sclass == SECCLASS_FILE) 1572 isec->sclass = inode_mode_to_security_class(inode->i_mode); 1573 return rc; 1574 } 1575 1576 /* Convert a Linux signal to an access vector. */ 1577 static inline u32 signal_to_av(int sig) 1578 { 1579 u32 perm = 0; 1580 1581 switch (sig) { 1582 case SIGCHLD: 1583 /* Commonly granted from child to parent. */ 1584 perm = PROCESS__SIGCHLD; 1585 break; 1586 case SIGKILL: 1587 /* Cannot be caught or ignored */ 1588 perm = PROCESS__SIGKILL; 1589 break; 1590 case SIGSTOP: 1591 /* Cannot be caught or ignored */ 1592 perm = PROCESS__SIGSTOP; 1593 break; 1594 default: 1595 /* All other signals. */ 1596 perm = PROCESS__SIGNAL; 1597 break; 1598 } 1599 1600 return perm; 1601 } 1602 1603 /* 1604 * Check permission between a pair of credentials 1605 * fork check, ptrace check, etc. 1606 */ 1607 static int cred_has_perm(const struct cred *actor, 1608 const struct cred *target, 1609 u32 perms) 1610 { 1611 u32 asid = cred_sid(actor), tsid = cred_sid(target); 1612 1613 return avc_has_perm(asid, tsid, SECCLASS_PROCESS, perms, NULL); 1614 } 1615 1616 /* 1617 * Check permission between a pair of tasks, e.g. signal checks, 1618 * fork check, ptrace check, etc. 1619 * tsk1 is the actor and tsk2 is the target 1620 * - this uses the default subjective creds of tsk1 1621 */ 1622 static int task_has_perm(const struct task_struct *tsk1, 1623 const struct task_struct *tsk2, 1624 u32 perms) 1625 { 1626 const struct task_security_struct *__tsec1, *__tsec2; 1627 u32 sid1, sid2; 1628 1629 rcu_read_lock(); 1630 __tsec1 = __task_cred(tsk1)->security; sid1 = __tsec1->sid; 1631 __tsec2 = __task_cred(tsk2)->security; sid2 = __tsec2->sid; 1632 rcu_read_unlock(); 1633 return avc_has_perm(sid1, sid2, SECCLASS_PROCESS, perms, NULL); 1634 } 1635 1636 /* 1637 * Check permission between current and another task, e.g. signal checks, 1638 * fork check, ptrace check, etc. 1639 * current is the actor and tsk2 is the target 1640 * - this uses current's subjective creds 1641 */ 1642 static int current_has_perm(const struct task_struct *tsk, 1643 u32 perms) 1644 { 1645 u32 sid, tsid; 1646 1647 sid = current_sid(); 1648 tsid = task_sid(tsk); 1649 return avc_has_perm(sid, tsid, SECCLASS_PROCESS, perms, NULL); 1650 } 1651 1652 #if CAP_LAST_CAP > 63 1653 #error Fix SELinux to handle capabilities > 63. 1654 #endif 1655 1656 /* Check whether a task is allowed to use a capability. */ 1657 static int cred_has_capability(const struct cred *cred, 1658 int cap, int audit, bool initns) 1659 { 1660 struct common_audit_data ad; 1661 struct av_decision avd; 1662 u16 sclass; 1663 u32 sid = cred_sid(cred); 1664 u32 av = CAP_TO_MASK(cap); 1665 int rc; 1666 1667 ad.type = LSM_AUDIT_DATA_CAP; 1668 ad.u.cap = cap; 1669 1670 switch (CAP_TO_INDEX(cap)) { 1671 case 0: 1672 sclass = initns ? SECCLASS_CAPABILITY : SECCLASS_CAP_USERNS; 1673 break; 1674 case 1: 1675 sclass = initns ? SECCLASS_CAPABILITY2 : SECCLASS_CAP2_USERNS; 1676 break; 1677 default: 1678 printk(KERN_ERR 1679 "SELinux: out of range capability %d\n", cap); 1680 BUG(); 1681 return -EINVAL; 1682 } 1683 1684 rc = avc_has_perm_noaudit(sid, sid, sclass, av, 0, &avd); 1685 if (audit == SECURITY_CAP_AUDIT) { 1686 int rc2 = avc_audit(sid, sid, sclass, av, &avd, rc, &ad, 0); 1687 if (rc2) 1688 return rc2; 1689 } 1690 return rc; 1691 } 1692 1693 /* Check whether a task is allowed to use a system operation. */ 1694 static int task_has_system(struct task_struct *tsk, 1695 u32 perms) 1696 { 1697 u32 sid = task_sid(tsk); 1698 1699 return avc_has_perm(sid, SECINITSID_KERNEL, 1700 SECCLASS_SYSTEM, perms, NULL); 1701 } 1702 1703 /* Check whether a task has a particular permission to an inode. 1704 The 'adp' parameter is optional and allows other audit 1705 data to be passed (e.g. the dentry). */ 1706 static int inode_has_perm(const struct cred *cred, 1707 struct inode *inode, 1708 u32 perms, 1709 struct common_audit_data *adp) 1710 { 1711 struct inode_security_struct *isec; 1712 u32 sid; 1713 1714 validate_creds(cred); 1715 1716 if (unlikely(IS_PRIVATE(inode))) 1717 return 0; 1718 1719 sid = cred_sid(cred); 1720 isec = inode->i_security; 1721 1722 return avc_has_perm(sid, isec->sid, isec->sclass, perms, adp); 1723 } 1724 1725 /* Same as inode_has_perm, but pass explicit audit data containing 1726 the dentry to help the auditing code to more easily generate the 1727 pathname if needed. */ 1728 static inline int dentry_has_perm(const struct cred *cred, 1729 struct dentry *dentry, 1730 u32 av) 1731 { 1732 struct inode *inode = d_backing_inode(dentry); 1733 struct common_audit_data ad; 1734 1735 ad.type = LSM_AUDIT_DATA_DENTRY; 1736 ad.u.dentry = dentry; 1737 __inode_security_revalidate(inode, dentry, true); 1738 return inode_has_perm(cred, inode, av, &ad); 1739 } 1740 1741 /* Same as inode_has_perm, but pass explicit audit data containing 1742 the path to help the auditing code to more easily generate the 1743 pathname if needed. */ 1744 static inline int path_has_perm(const struct cred *cred, 1745 const struct path *path, 1746 u32 av) 1747 { 1748 struct inode *inode = d_backing_inode(path->dentry); 1749 struct common_audit_data ad; 1750 1751 ad.type = LSM_AUDIT_DATA_PATH; 1752 ad.u.path = *path; 1753 __inode_security_revalidate(inode, path->dentry, true); 1754 return inode_has_perm(cred, inode, av, &ad); 1755 } 1756 1757 /* Same as path_has_perm, but uses the inode from the file struct. */ 1758 static inline int file_path_has_perm(const struct cred *cred, 1759 struct file *file, 1760 u32 av) 1761 { 1762 struct common_audit_data ad; 1763 1764 ad.type = LSM_AUDIT_DATA_FILE; 1765 ad.u.file = file; 1766 return inode_has_perm(cred, file_inode(file), av, &ad); 1767 } 1768 1769 /* Check whether a task can use an open file descriptor to 1770 access an inode in a given way. Check access to the 1771 descriptor itself, and then use dentry_has_perm to 1772 check a particular permission to the file. 1773 Access to the descriptor is implicitly granted if it 1774 has the same SID as the process. If av is zero, then 1775 access to the file is not checked, e.g. for cases 1776 where only the descriptor is affected like seek. */ 1777 static int file_has_perm(const struct cred *cred, 1778 struct file *file, 1779 u32 av) 1780 { 1781 struct file_security_struct *fsec = file->f_security; 1782 struct inode *inode = file_inode(file); 1783 struct common_audit_data ad; 1784 u32 sid = cred_sid(cred); 1785 int rc; 1786 1787 ad.type = LSM_AUDIT_DATA_FILE; 1788 ad.u.file = file; 1789 1790 if (sid != fsec->sid) { 1791 rc = avc_has_perm(sid, fsec->sid, 1792 SECCLASS_FD, 1793 FD__USE, 1794 &ad); 1795 if (rc) 1796 goto out; 1797 } 1798 1799 /* av is zero if only checking access to the descriptor. */ 1800 rc = 0; 1801 if (av) 1802 rc = inode_has_perm(cred, inode, av, &ad); 1803 1804 out: 1805 return rc; 1806 } 1807 1808 /* 1809 * Determine the label for an inode that might be unioned. 1810 */ 1811 static int 1812 selinux_determine_inode_label(const struct task_security_struct *tsec, 1813 struct inode *dir, 1814 const struct qstr *name, u16 tclass, 1815 u32 *_new_isid) 1816 { 1817 const struct superblock_security_struct *sbsec = dir->i_sb->s_security; 1818 1819 if ((sbsec->flags & SE_SBINITIALIZED) && 1820 (sbsec->behavior == SECURITY_FS_USE_MNTPOINT)) { 1821 *_new_isid = sbsec->mntpoint_sid; 1822 } else if ((sbsec->flags & SBLABEL_MNT) && 1823 tsec->create_sid) { 1824 *_new_isid = tsec->create_sid; 1825 } else { 1826 const struct inode_security_struct *dsec = inode_security(dir); 1827 return security_transition_sid(tsec->sid, dsec->sid, tclass, 1828 name, _new_isid); 1829 } 1830 1831 return 0; 1832 } 1833 1834 /* Check whether a task can create a file. */ 1835 static int may_create(struct inode *dir, 1836 struct dentry *dentry, 1837 u16 tclass) 1838 { 1839 const struct task_security_struct *tsec = current_security(); 1840 struct inode_security_struct *dsec; 1841 struct superblock_security_struct *sbsec; 1842 u32 sid, newsid; 1843 struct common_audit_data ad; 1844 int rc; 1845 1846 dsec = inode_security(dir); 1847 sbsec = dir->i_sb->s_security; 1848 1849 sid = tsec->sid; 1850 1851 ad.type = LSM_AUDIT_DATA_DENTRY; 1852 ad.u.dentry = dentry; 1853 1854 rc = avc_has_perm(sid, dsec->sid, SECCLASS_DIR, 1855 DIR__ADD_NAME | DIR__SEARCH, 1856 &ad); 1857 if (rc) 1858 return rc; 1859 1860 rc = selinux_determine_inode_label(current_security(), dir, 1861 &dentry->d_name, tclass, &newsid); 1862 if (rc) 1863 return rc; 1864 1865 rc = avc_has_perm(sid, newsid, tclass, FILE__CREATE, &ad); 1866 if (rc) 1867 return rc; 1868 1869 return avc_has_perm(newsid, sbsec->sid, 1870 SECCLASS_FILESYSTEM, 1871 FILESYSTEM__ASSOCIATE, &ad); 1872 } 1873 1874 /* Check whether a task can create a key. */ 1875 static int may_create_key(u32 ksid, 1876 struct task_struct *ctx) 1877 { 1878 u32 sid = task_sid(ctx); 1879 1880 return avc_has_perm(sid, ksid, SECCLASS_KEY, KEY__CREATE, NULL); 1881 } 1882 1883 #define MAY_LINK 0 1884 #define MAY_UNLINK 1 1885 #define MAY_RMDIR 2 1886 1887 /* Check whether a task can link, unlink, or rmdir a file/directory. */ 1888 static int may_link(struct inode *dir, 1889 struct dentry *dentry, 1890 int kind) 1891 1892 { 1893 struct inode_security_struct *dsec, *isec; 1894 struct common_audit_data ad; 1895 u32 sid = current_sid(); 1896 u32 av; 1897 int rc; 1898 1899 dsec = inode_security(dir); 1900 isec = backing_inode_security(dentry); 1901 1902 ad.type = LSM_AUDIT_DATA_DENTRY; 1903 ad.u.dentry = dentry; 1904 1905 av = DIR__SEARCH; 1906 av |= (kind ? DIR__REMOVE_NAME : DIR__ADD_NAME); 1907 rc = avc_has_perm(sid, dsec->sid, SECCLASS_DIR, av, &ad); 1908 if (rc) 1909 return rc; 1910 1911 switch (kind) { 1912 case MAY_LINK: 1913 av = FILE__LINK; 1914 break; 1915 case MAY_UNLINK: 1916 av = FILE__UNLINK; 1917 break; 1918 case MAY_RMDIR: 1919 av = DIR__RMDIR; 1920 break; 1921 default: 1922 printk(KERN_WARNING "SELinux: %s: unrecognized kind %d\n", 1923 __func__, kind); 1924 return 0; 1925 } 1926 1927 rc = avc_has_perm(sid, isec->sid, isec->sclass, av, &ad); 1928 return rc; 1929 } 1930 1931 static inline int may_rename(struct inode *old_dir, 1932 struct dentry *old_dentry, 1933 struct inode *new_dir, 1934 struct dentry *new_dentry) 1935 { 1936 struct inode_security_struct *old_dsec, *new_dsec, *old_isec, *new_isec; 1937 struct common_audit_data ad; 1938 u32 sid = current_sid(); 1939 u32 av; 1940 int old_is_dir, new_is_dir; 1941 int rc; 1942 1943 old_dsec = inode_security(old_dir); 1944 old_isec = backing_inode_security(old_dentry); 1945 old_is_dir = d_is_dir(old_dentry); 1946 new_dsec = inode_security(new_dir); 1947 1948 ad.type = LSM_AUDIT_DATA_DENTRY; 1949 1950 ad.u.dentry = old_dentry; 1951 rc = avc_has_perm(sid, old_dsec->sid, SECCLASS_DIR, 1952 DIR__REMOVE_NAME | DIR__SEARCH, &ad); 1953 if (rc) 1954 return rc; 1955 rc = avc_has_perm(sid, old_isec->sid, 1956 old_isec->sclass, FILE__RENAME, &ad); 1957 if (rc) 1958 return rc; 1959 if (old_is_dir && new_dir != old_dir) { 1960 rc = avc_has_perm(sid, old_isec->sid, 1961 old_isec->sclass, DIR__REPARENT, &ad); 1962 if (rc) 1963 return rc; 1964 } 1965 1966 ad.u.dentry = new_dentry; 1967 av = DIR__ADD_NAME | DIR__SEARCH; 1968 if (d_is_positive(new_dentry)) 1969 av |= DIR__REMOVE_NAME; 1970 rc = avc_has_perm(sid, new_dsec->sid, SECCLASS_DIR, av, &ad); 1971 if (rc) 1972 return rc; 1973 if (d_is_positive(new_dentry)) { 1974 new_isec = backing_inode_security(new_dentry); 1975 new_is_dir = d_is_dir(new_dentry); 1976 rc = avc_has_perm(sid, new_isec->sid, 1977 new_isec->sclass, 1978 (new_is_dir ? DIR__RMDIR : FILE__UNLINK), &ad); 1979 if (rc) 1980 return rc; 1981 } 1982 1983 return 0; 1984 } 1985 1986 /* Check whether a task can perform a filesystem operation. */ 1987 static int superblock_has_perm(const struct cred *cred, 1988 struct super_block *sb, 1989 u32 perms, 1990 struct common_audit_data *ad) 1991 { 1992 struct superblock_security_struct *sbsec; 1993 u32 sid = cred_sid(cred); 1994 1995 sbsec = sb->s_security; 1996 return avc_has_perm(sid, sbsec->sid, SECCLASS_FILESYSTEM, perms, ad); 1997 } 1998 1999 /* Convert a Linux mode and permission mask to an access vector. */ 2000 static inline u32 file_mask_to_av(int mode, int mask) 2001 { 2002 u32 av = 0; 2003 2004 if (!S_ISDIR(mode)) { 2005 if (mask & MAY_EXEC) 2006 av |= FILE__EXECUTE; 2007 if (mask & MAY_READ) 2008 av |= FILE__READ; 2009 2010 if (mask & MAY_APPEND) 2011 av |= FILE__APPEND; 2012 else if (mask & MAY_WRITE) 2013 av |= FILE__WRITE; 2014 2015 } else { 2016 if (mask & MAY_EXEC) 2017 av |= DIR__SEARCH; 2018 if (mask & MAY_WRITE) 2019 av |= DIR__WRITE; 2020 if (mask & MAY_READ) 2021 av |= DIR__READ; 2022 } 2023 2024 return av; 2025 } 2026 2027 /* Convert a Linux file to an access vector. */ 2028 static inline u32 file_to_av(struct file *file) 2029 { 2030 u32 av = 0; 2031 2032 if (file->f_mode & FMODE_READ) 2033 av |= FILE__READ; 2034 if (file->f_mode & FMODE_WRITE) { 2035 if (file->f_flags & O_APPEND) 2036 av |= FILE__APPEND; 2037 else 2038 av |= FILE__WRITE; 2039 } 2040 if (!av) { 2041 /* 2042 * Special file opened with flags 3 for ioctl-only use. 2043 */ 2044 av = FILE__IOCTL; 2045 } 2046 2047 return av; 2048 } 2049 2050 /* 2051 * Convert a file to an access vector and include the correct open 2052 * open permission. 2053 */ 2054 static inline u32 open_file_to_av(struct file *file) 2055 { 2056 u32 av = file_to_av(file); 2057 2058 if (selinux_policycap_openperm) 2059 av |= FILE__OPEN; 2060 2061 return av; 2062 } 2063 2064 /* Hook functions begin here. */ 2065 2066 static int selinux_binder_set_context_mgr(struct task_struct *mgr) 2067 { 2068 u32 mysid = current_sid(); 2069 u32 mgrsid = task_sid(mgr); 2070 2071 return avc_has_perm(mysid, mgrsid, SECCLASS_BINDER, 2072 BINDER__SET_CONTEXT_MGR, NULL); 2073 } 2074 2075 static int selinux_binder_transaction(struct task_struct *from, 2076 struct task_struct *to) 2077 { 2078 u32 mysid = current_sid(); 2079 u32 fromsid = task_sid(from); 2080 u32 tosid = task_sid(to); 2081 int rc; 2082 2083 if (mysid != fromsid) { 2084 rc = avc_has_perm(mysid, fromsid, SECCLASS_BINDER, 2085 BINDER__IMPERSONATE, NULL); 2086 if (rc) 2087 return rc; 2088 } 2089 2090 return avc_has_perm(fromsid, tosid, SECCLASS_BINDER, BINDER__CALL, 2091 NULL); 2092 } 2093 2094 static int selinux_binder_transfer_binder(struct task_struct *from, 2095 struct task_struct *to) 2096 { 2097 u32 fromsid = task_sid(from); 2098 u32 tosid = task_sid(to); 2099 2100 return avc_has_perm(fromsid, tosid, SECCLASS_BINDER, BINDER__TRANSFER, 2101 NULL); 2102 } 2103 2104 static int selinux_binder_transfer_file(struct task_struct *from, 2105 struct task_struct *to, 2106 struct file *file) 2107 { 2108 u32 sid = task_sid(to); 2109 struct file_security_struct *fsec = file->f_security; 2110 struct dentry *dentry = file->f_path.dentry; 2111 struct inode_security_struct *isec; 2112 struct common_audit_data ad; 2113 int rc; 2114 2115 ad.type = LSM_AUDIT_DATA_PATH; 2116 ad.u.path = file->f_path; 2117 2118 if (sid != fsec->sid) { 2119 rc = avc_has_perm(sid, fsec->sid, 2120 SECCLASS_FD, 2121 FD__USE, 2122 &ad); 2123 if (rc) 2124 return rc; 2125 } 2126 2127 if (unlikely(IS_PRIVATE(d_backing_inode(dentry)))) 2128 return 0; 2129 2130 isec = backing_inode_security(dentry); 2131 return avc_has_perm(sid, isec->sid, isec->sclass, file_to_av(file), 2132 &ad); 2133 } 2134 2135 static int selinux_ptrace_access_check(struct task_struct *child, 2136 unsigned int mode) 2137 { 2138 if (mode & PTRACE_MODE_READ) { 2139 u32 sid = current_sid(); 2140 u32 csid = task_sid(child); 2141 return avc_has_perm(sid, csid, SECCLASS_FILE, FILE__READ, NULL); 2142 } 2143 2144 return current_has_perm(child, PROCESS__PTRACE); 2145 } 2146 2147 static int selinux_ptrace_traceme(struct task_struct *parent) 2148 { 2149 return task_has_perm(parent, current, PROCESS__PTRACE); 2150 } 2151 2152 static int selinux_capget(struct task_struct *target, kernel_cap_t *effective, 2153 kernel_cap_t *inheritable, kernel_cap_t *permitted) 2154 { 2155 return current_has_perm(target, PROCESS__GETCAP); 2156 } 2157 2158 static int selinux_capset(struct cred *new, const struct cred *old, 2159 const kernel_cap_t *effective, 2160 const kernel_cap_t *inheritable, 2161 const kernel_cap_t *permitted) 2162 { 2163 return cred_has_perm(old, new, PROCESS__SETCAP); 2164 } 2165 2166 /* 2167 * (This comment used to live with the selinux_task_setuid hook, 2168 * which was removed). 2169 * 2170 * Since setuid only affects the current process, and since the SELinux 2171 * controls are not based on the Linux identity attributes, SELinux does not 2172 * need to control this operation. However, SELinux does control the use of 2173 * the CAP_SETUID and CAP_SETGID capabilities using the capable hook. 2174 */ 2175 2176 static int selinux_capable(const struct cred *cred, struct user_namespace *ns, 2177 int cap, int audit) 2178 { 2179 return cred_has_capability(cred, cap, audit, ns == &init_user_ns); 2180 } 2181 2182 static int selinux_quotactl(int cmds, int type, int id, struct super_block *sb) 2183 { 2184 const struct cred *cred = current_cred(); 2185 int rc = 0; 2186 2187 if (!sb) 2188 return 0; 2189 2190 switch (cmds) { 2191 case Q_SYNC: 2192 case Q_QUOTAON: 2193 case Q_QUOTAOFF: 2194 case Q_SETINFO: 2195 case Q_SETQUOTA: 2196 rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAMOD, NULL); 2197 break; 2198 case Q_GETFMT: 2199 case Q_GETINFO: 2200 case Q_GETQUOTA: 2201 rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAGET, NULL); 2202 break; 2203 default: 2204 rc = 0; /* let the kernel handle invalid cmds */ 2205 break; 2206 } 2207 return rc; 2208 } 2209 2210 static int selinux_quota_on(struct dentry *dentry) 2211 { 2212 const struct cred *cred = current_cred(); 2213 2214 return dentry_has_perm(cred, dentry, FILE__QUOTAON); 2215 } 2216 2217 static int selinux_syslog(int type) 2218 { 2219 int rc; 2220 2221 switch (type) { 2222 case SYSLOG_ACTION_READ_ALL: /* Read last kernel messages */ 2223 case SYSLOG_ACTION_SIZE_BUFFER: /* Return size of the log buffer */ 2224 rc = task_has_system(current, SYSTEM__SYSLOG_READ); 2225 break; 2226 case SYSLOG_ACTION_CONSOLE_OFF: /* Disable logging to console */ 2227 case SYSLOG_ACTION_CONSOLE_ON: /* Enable logging to console */ 2228 /* Set level of messages printed to console */ 2229 case SYSLOG_ACTION_CONSOLE_LEVEL: 2230 rc = task_has_system(current, SYSTEM__SYSLOG_CONSOLE); 2231 break; 2232 case SYSLOG_ACTION_CLOSE: /* Close log */ 2233 case SYSLOG_ACTION_OPEN: /* Open log */ 2234 case SYSLOG_ACTION_READ: /* Read from log */ 2235 case SYSLOG_ACTION_READ_CLEAR: /* Read/clear last kernel messages */ 2236 case SYSLOG_ACTION_CLEAR: /* Clear ring buffer */ 2237 default: 2238 rc = task_has_system(current, SYSTEM__SYSLOG_MOD); 2239 break; 2240 } 2241 return rc; 2242 } 2243 2244 /* 2245 * Check that a process has enough memory to allocate a new virtual 2246 * mapping. 0 means there is enough memory for the allocation to 2247 * succeed and -ENOMEM implies there is not. 2248 * 2249 * Do not audit the selinux permission check, as this is applied to all 2250 * processes that allocate mappings. 2251 */ 2252 static int selinux_vm_enough_memory(struct mm_struct *mm, long pages) 2253 { 2254 int rc, cap_sys_admin = 0; 2255 2256 rc = cred_has_capability(current_cred(), CAP_SYS_ADMIN, 2257 SECURITY_CAP_NOAUDIT, true); 2258 if (rc == 0) 2259 cap_sys_admin = 1; 2260 2261 return cap_sys_admin; 2262 } 2263 2264 /* binprm security operations */ 2265 2266 static u32 ptrace_parent_sid(struct task_struct *task) 2267 { 2268 u32 sid = 0; 2269 struct task_struct *tracer; 2270 2271 rcu_read_lock(); 2272 tracer = ptrace_parent(task); 2273 if (tracer) 2274 sid = task_sid(tracer); 2275 rcu_read_unlock(); 2276 2277 return sid; 2278 } 2279 2280 static int check_nnp_nosuid(const struct linux_binprm *bprm, 2281 const struct task_security_struct *old_tsec, 2282 const struct task_security_struct *new_tsec) 2283 { 2284 int nnp = (bprm->unsafe & LSM_UNSAFE_NO_NEW_PRIVS); 2285 int nosuid = !mnt_may_suid(bprm->file->f_path.mnt); 2286 int rc; 2287 2288 if (!nnp && !nosuid) 2289 return 0; /* neither NNP nor nosuid */ 2290 2291 if (new_tsec->sid == old_tsec->sid) 2292 return 0; /* No change in credentials */ 2293 2294 /* 2295 * The only transitions we permit under NNP or nosuid 2296 * are transitions to bounded SIDs, i.e. SIDs that are 2297 * guaranteed to only be allowed a subset of the permissions 2298 * of the current SID. 2299 */ 2300 rc = security_bounded_transition(old_tsec->sid, new_tsec->sid); 2301 if (rc) { 2302 /* 2303 * On failure, preserve the errno values for NNP vs nosuid. 2304 * NNP: Operation not permitted for caller. 2305 * nosuid: Permission denied to file. 2306 */ 2307 if (nnp) 2308 return -EPERM; 2309 else 2310 return -EACCES; 2311 } 2312 return 0; 2313 } 2314 2315 static int selinux_bprm_set_creds(struct linux_binprm *bprm) 2316 { 2317 const struct task_security_struct *old_tsec; 2318 struct task_security_struct *new_tsec; 2319 struct inode_security_struct *isec; 2320 struct common_audit_data ad; 2321 struct inode *inode = file_inode(bprm->file); 2322 int rc; 2323 2324 /* SELinux context only depends on initial program or script and not 2325 * the script interpreter */ 2326 if (bprm->cred_prepared) 2327 return 0; 2328 2329 old_tsec = current_security(); 2330 new_tsec = bprm->cred->security; 2331 isec = inode_security(inode); 2332 2333 /* Default to the current task SID. */ 2334 new_tsec->sid = old_tsec->sid; 2335 new_tsec->osid = old_tsec->sid; 2336 2337 /* Reset fs, key, and sock SIDs on execve. */ 2338 new_tsec->create_sid = 0; 2339 new_tsec->keycreate_sid = 0; 2340 new_tsec->sockcreate_sid = 0; 2341 2342 if (old_tsec->exec_sid) { 2343 new_tsec->sid = old_tsec->exec_sid; 2344 /* Reset exec SID on execve. */ 2345 new_tsec->exec_sid = 0; 2346 2347 /* Fail on NNP or nosuid if not an allowed transition. */ 2348 rc = check_nnp_nosuid(bprm, old_tsec, new_tsec); 2349 if (rc) 2350 return rc; 2351 } else { 2352 /* Check for a default transition on this program. */ 2353 rc = security_transition_sid(old_tsec->sid, isec->sid, 2354 SECCLASS_PROCESS, NULL, 2355 &new_tsec->sid); 2356 if (rc) 2357 return rc; 2358 2359 /* 2360 * Fallback to old SID on NNP or nosuid if not an allowed 2361 * transition. 2362 */ 2363 rc = check_nnp_nosuid(bprm, old_tsec, new_tsec); 2364 if (rc) 2365 new_tsec->sid = old_tsec->sid; 2366 } 2367 2368 ad.type = LSM_AUDIT_DATA_FILE; 2369 ad.u.file = bprm->file; 2370 2371 if (new_tsec->sid == old_tsec->sid) { 2372 rc = avc_has_perm(old_tsec->sid, isec->sid, 2373 SECCLASS_FILE, FILE__EXECUTE_NO_TRANS, &ad); 2374 if (rc) 2375 return rc; 2376 } else { 2377 /* Check permissions for the transition. */ 2378 rc = avc_has_perm(old_tsec->sid, new_tsec->sid, 2379 SECCLASS_PROCESS, PROCESS__TRANSITION, &ad); 2380 if (rc) 2381 return rc; 2382 2383 rc = avc_has_perm(new_tsec->sid, isec->sid, 2384 SECCLASS_FILE, FILE__ENTRYPOINT, &ad); 2385 if (rc) 2386 return rc; 2387 2388 /* Check for shared state */ 2389 if (bprm->unsafe & LSM_UNSAFE_SHARE) { 2390 rc = avc_has_perm(old_tsec->sid, new_tsec->sid, 2391 SECCLASS_PROCESS, PROCESS__SHARE, 2392 NULL); 2393 if (rc) 2394 return -EPERM; 2395 } 2396 2397 /* Make sure that anyone attempting to ptrace over a task that 2398 * changes its SID has the appropriate permit */ 2399 if (bprm->unsafe & 2400 (LSM_UNSAFE_PTRACE | LSM_UNSAFE_PTRACE_CAP)) { 2401 u32 ptsid = ptrace_parent_sid(current); 2402 if (ptsid != 0) { 2403 rc = avc_has_perm(ptsid, new_tsec->sid, 2404 SECCLASS_PROCESS, 2405 PROCESS__PTRACE, NULL); 2406 if (rc) 2407 return -EPERM; 2408 } 2409 } 2410 2411 /* Clear any possibly unsafe personality bits on exec: */ 2412 bprm->per_clear |= PER_CLEAR_ON_SETID; 2413 } 2414 2415 return 0; 2416 } 2417 2418 static int selinux_bprm_secureexec(struct linux_binprm *bprm) 2419 { 2420 const struct task_security_struct *tsec = current_security(); 2421 u32 sid, osid; 2422 int atsecure = 0; 2423 2424 sid = tsec->sid; 2425 osid = tsec->osid; 2426 2427 if (osid != sid) { 2428 /* Enable secure mode for SIDs transitions unless 2429 the noatsecure permission is granted between 2430 the two SIDs, i.e. ahp returns 0. */ 2431 atsecure = avc_has_perm(osid, sid, 2432 SECCLASS_PROCESS, 2433 PROCESS__NOATSECURE, NULL); 2434 } 2435 2436 return !!atsecure; 2437 } 2438 2439 static int match_file(const void *p, struct file *file, unsigned fd) 2440 { 2441 return file_has_perm(p, file, file_to_av(file)) ? fd + 1 : 0; 2442 } 2443 2444 /* Derived from fs/exec.c:flush_old_files. */ 2445 static inline void flush_unauthorized_files(const struct cred *cred, 2446 struct files_struct *files) 2447 { 2448 struct file *file, *devnull = NULL; 2449 struct tty_struct *tty; 2450 int drop_tty = 0; 2451 unsigned n; 2452 2453 tty = get_current_tty(); 2454 if (tty) { 2455 spin_lock(&tty->files_lock); 2456 if (!list_empty(&tty->tty_files)) { 2457 struct tty_file_private *file_priv; 2458 2459 /* Revalidate access to controlling tty. 2460 Use file_path_has_perm on the tty path directly 2461 rather than using file_has_perm, as this particular 2462 open file may belong to another process and we are 2463 only interested in the inode-based check here. */ 2464 file_priv = list_first_entry(&tty->tty_files, 2465 struct tty_file_private, list); 2466 file = file_priv->file; 2467 if (file_path_has_perm(cred, file, FILE__READ | FILE__WRITE)) 2468 drop_tty = 1; 2469 } 2470 spin_unlock(&tty->files_lock); 2471 tty_kref_put(tty); 2472 } 2473 /* Reset controlling tty. */ 2474 if (drop_tty) 2475 no_tty(); 2476 2477 /* Revalidate access to inherited open files. */ 2478 n = iterate_fd(files, 0, match_file, cred); 2479 if (!n) /* none found? */ 2480 return; 2481 2482 devnull = dentry_open(&selinux_null, O_RDWR, cred); 2483 if (IS_ERR(devnull)) 2484 devnull = NULL; 2485 /* replace all the matching ones with this */ 2486 do { 2487 replace_fd(n - 1, devnull, 0); 2488 } while ((n = iterate_fd(files, n, match_file, cred)) != 0); 2489 if (devnull) 2490 fput(devnull); 2491 } 2492 2493 /* 2494 * Prepare a process for imminent new credential changes due to exec 2495 */ 2496 static void selinux_bprm_committing_creds(struct linux_binprm *bprm) 2497 { 2498 struct task_security_struct *new_tsec; 2499 struct rlimit *rlim, *initrlim; 2500 int rc, i; 2501 2502 new_tsec = bprm->cred->security; 2503 if (new_tsec->sid == new_tsec->osid) 2504 return; 2505 2506 /* Close files for which the new task SID is not authorized. */ 2507 flush_unauthorized_files(bprm->cred, current->files); 2508 2509 /* Always clear parent death signal on SID transitions. */ 2510 current->pdeath_signal = 0; 2511 2512 /* Check whether the new SID can inherit resource limits from the old 2513 * SID. If not, reset all soft limits to the lower of the current 2514 * task's hard limit and the init task's soft limit. 2515 * 2516 * Note that the setting of hard limits (even to lower them) can be 2517 * controlled by the setrlimit check. The inclusion of the init task's 2518 * soft limit into the computation is to avoid resetting soft limits 2519 * higher than the default soft limit for cases where the default is 2520 * lower than the hard limit, e.g. RLIMIT_CORE or RLIMIT_STACK. 2521 */ 2522 rc = avc_has_perm(new_tsec->osid, new_tsec->sid, SECCLASS_PROCESS, 2523 PROCESS__RLIMITINH, NULL); 2524 if (rc) { 2525 /* protect against do_prlimit() */ 2526 task_lock(current); 2527 for (i = 0; i < RLIM_NLIMITS; i++) { 2528 rlim = current->signal->rlim + i; 2529 initrlim = init_task.signal->rlim + i; 2530 rlim->rlim_cur = min(rlim->rlim_max, initrlim->rlim_cur); 2531 } 2532 task_unlock(current); 2533 update_rlimit_cpu(current, rlimit(RLIMIT_CPU)); 2534 } 2535 } 2536 2537 /* 2538 * Clean up the process immediately after the installation of new credentials 2539 * due to exec 2540 */ 2541 static void selinux_bprm_committed_creds(struct linux_binprm *bprm) 2542 { 2543 const struct task_security_struct *tsec = current_security(); 2544 struct itimerval itimer; 2545 u32 osid, sid; 2546 int rc, i; 2547 2548 osid = tsec->osid; 2549 sid = tsec->sid; 2550 2551 if (sid == osid) 2552 return; 2553 2554 /* Check whether the new SID can inherit signal state from the old SID. 2555 * If not, clear itimers to avoid subsequent signal generation and 2556 * flush and unblock signals. 2557 * 2558 * This must occur _after_ the task SID has been updated so that any 2559 * kill done after the flush will be checked against the new SID. 2560 */ 2561 rc = avc_has_perm(osid, sid, SECCLASS_PROCESS, PROCESS__SIGINH, NULL); 2562 if (rc) { 2563 memset(&itimer, 0, sizeof itimer); 2564 for (i = 0; i < 3; i++) 2565 do_setitimer(i, &itimer, NULL); 2566 spin_lock_irq(¤t->sighand->siglock); 2567 if (!fatal_signal_pending(current)) { 2568 flush_sigqueue(¤t->pending); 2569 flush_sigqueue(¤t->signal->shared_pending); 2570 flush_signal_handlers(current, 1); 2571 sigemptyset(¤t->blocked); 2572 recalc_sigpending(); 2573 } 2574 spin_unlock_irq(¤t->sighand->siglock); 2575 } 2576 2577 /* Wake up the parent if it is waiting so that it can recheck 2578 * wait permission to the new task SID. */ 2579 read_lock(&tasklist_lock); 2580 __wake_up_parent(current, current->real_parent); 2581 read_unlock(&tasklist_lock); 2582 } 2583 2584 /* superblock security operations */ 2585 2586 static int selinux_sb_alloc_security(struct super_block *sb) 2587 { 2588 return superblock_alloc_security(sb); 2589 } 2590 2591 static void selinux_sb_free_security(struct super_block *sb) 2592 { 2593 superblock_free_security(sb); 2594 } 2595 2596 static inline int match_prefix(char *prefix, int plen, char *option, int olen) 2597 { 2598 if (plen > olen) 2599 return 0; 2600 2601 return !memcmp(prefix, option, plen); 2602 } 2603 2604 static inline int selinux_option(char *option, int len) 2605 { 2606 return (match_prefix(CONTEXT_STR, sizeof(CONTEXT_STR)-1, option, len) || 2607 match_prefix(FSCONTEXT_STR, sizeof(FSCONTEXT_STR)-1, option, len) || 2608 match_prefix(DEFCONTEXT_STR, sizeof(DEFCONTEXT_STR)-1, option, len) || 2609 match_prefix(ROOTCONTEXT_STR, sizeof(ROOTCONTEXT_STR)-1, option, len) || 2610 match_prefix(LABELSUPP_STR, sizeof(LABELSUPP_STR)-1, option, len)); 2611 } 2612 2613 static inline void take_option(char **to, char *from, int *first, int len) 2614 { 2615 if (!*first) { 2616 **to = ','; 2617 *to += 1; 2618 } else 2619 *first = 0; 2620 memcpy(*to, from, len); 2621 *to += len; 2622 } 2623 2624 static inline void take_selinux_option(char **to, char *from, int *first, 2625 int len) 2626 { 2627 int current_size = 0; 2628 2629 if (!*first) { 2630 **to = '|'; 2631 *to += 1; 2632 } else 2633 *first = 0; 2634 2635 while (current_size < len) { 2636 if (*from != '"') { 2637 **to = *from; 2638 *to += 1; 2639 } 2640 from += 1; 2641 current_size += 1; 2642 } 2643 } 2644 2645 static int selinux_sb_copy_data(char *orig, char *copy) 2646 { 2647 int fnosec, fsec, rc = 0; 2648 char *in_save, *in_curr, *in_end; 2649 char *sec_curr, *nosec_save, *nosec; 2650 int open_quote = 0; 2651 2652 in_curr = orig; 2653 sec_curr = copy; 2654 2655 nosec = (char *)get_zeroed_page(GFP_KERNEL); 2656 if (!nosec) { 2657 rc = -ENOMEM; 2658 goto out; 2659 } 2660 2661 nosec_save = nosec; 2662 fnosec = fsec = 1; 2663 in_save = in_end = orig; 2664 2665 do { 2666 if (*in_end == '"') 2667 open_quote = !open_quote; 2668 if ((*in_end == ',' && open_quote == 0) || 2669 *in_end == '\0') { 2670 int len = in_end - in_curr; 2671 2672 if (selinux_option(in_curr, len)) 2673 take_selinux_option(&sec_curr, in_curr, &fsec, len); 2674 else 2675 take_option(&nosec, in_curr, &fnosec, len); 2676 2677 in_curr = in_end + 1; 2678 } 2679 } while (*in_end++); 2680 2681 strcpy(in_save, nosec_save); 2682 free_page((unsigned long)nosec_save); 2683 out: 2684 return rc; 2685 } 2686 2687 static int selinux_sb_remount(struct super_block *sb, void *data) 2688 { 2689 int rc, i, *flags; 2690 struct security_mnt_opts opts; 2691 char *secdata, **mount_options; 2692 struct superblock_security_struct *sbsec = sb->s_security; 2693 2694 if (!(sbsec->flags & SE_SBINITIALIZED)) 2695 return 0; 2696 2697 if (!data) 2698 return 0; 2699 2700 if (sb->s_type->fs_flags & FS_BINARY_MOUNTDATA) 2701 return 0; 2702 2703 security_init_mnt_opts(&opts); 2704 secdata = alloc_secdata(); 2705 if (!secdata) 2706 return -ENOMEM; 2707 rc = selinux_sb_copy_data(data, secdata); 2708 if (rc) 2709 goto out_free_secdata; 2710 2711 rc = selinux_parse_opts_str(secdata, &opts); 2712 if (rc) 2713 goto out_free_secdata; 2714 2715 mount_options = opts.mnt_opts; 2716 flags = opts.mnt_opts_flags; 2717 2718 for (i = 0; i < opts.num_mnt_opts; i++) { 2719 u32 sid; 2720 2721 if (flags[i] == SBLABEL_MNT) 2722 continue; 2723 rc = security_context_str_to_sid(mount_options[i], &sid, GFP_KERNEL); 2724 if (rc) { 2725 printk(KERN_WARNING "SELinux: security_context_str_to_sid" 2726 "(%s) failed for (dev %s, type %s) errno=%d\n", 2727 mount_options[i], sb->s_id, sb->s_type->name, rc); 2728 goto out_free_opts; 2729 } 2730 rc = -EINVAL; 2731 switch (flags[i]) { 2732 case FSCONTEXT_MNT: 2733 if (bad_option(sbsec, FSCONTEXT_MNT, sbsec->sid, sid)) 2734 goto out_bad_option; 2735 break; 2736 case CONTEXT_MNT: 2737 if (bad_option(sbsec, CONTEXT_MNT, sbsec->mntpoint_sid, sid)) 2738 goto out_bad_option; 2739 break; 2740 case ROOTCONTEXT_MNT: { 2741 struct inode_security_struct *root_isec; 2742 root_isec = backing_inode_security(sb->s_root); 2743 2744 if (bad_option(sbsec, ROOTCONTEXT_MNT, root_isec->sid, sid)) 2745 goto out_bad_option; 2746 break; 2747 } 2748 case DEFCONTEXT_MNT: 2749 if (bad_option(sbsec, DEFCONTEXT_MNT, sbsec->def_sid, sid)) 2750 goto out_bad_option; 2751 break; 2752 default: 2753 goto out_free_opts; 2754 } 2755 } 2756 2757 rc = 0; 2758 out_free_opts: 2759 security_free_mnt_opts(&opts); 2760 out_free_secdata: 2761 free_secdata(secdata); 2762 return rc; 2763 out_bad_option: 2764 printk(KERN_WARNING "SELinux: unable to change security options " 2765 "during remount (dev %s, type=%s)\n", sb->s_id, 2766 sb->s_type->name); 2767 goto out_free_opts; 2768 } 2769 2770 static int selinux_sb_kern_mount(struct super_block *sb, int flags, void *data) 2771 { 2772 const struct cred *cred = current_cred(); 2773 struct common_audit_data ad; 2774 int rc; 2775 2776 rc = superblock_doinit(sb, data); 2777 if (rc) 2778 return rc; 2779 2780 /* Allow all mounts performed by the kernel */ 2781 if (flags & MS_KERNMOUNT) 2782 return 0; 2783 2784 ad.type = LSM_AUDIT_DATA_DENTRY; 2785 ad.u.dentry = sb->s_root; 2786 return superblock_has_perm(cred, sb, FILESYSTEM__MOUNT, &ad); 2787 } 2788 2789 static int selinux_sb_statfs(struct dentry *dentry) 2790 { 2791 const struct cred *cred = current_cred(); 2792 struct common_audit_data ad; 2793 2794 ad.type = LSM_AUDIT_DATA_DENTRY; 2795 ad.u.dentry = dentry->d_sb->s_root; 2796 return superblock_has_perm(cred, dentry->d_sb, FILESYSTEM__GETATTR, &ad); 2797 } 2798 2799 static int selinux_mount(const char *dev_name, 2800 const struct path *path, 2801 const char *type, 2802 unsigned long flags, 2803 void *data) 2804 { 2805 const struct cred *cred = current_cred(); 2806 2807 if (flags & MS_REMOUNT) 2808 return superblock_has_perm(cred, path->dentry->d_sb, 2809 FILESYSTEM__REMOUNT, NULL); 2810 else 2811 return path_has_perm(cred, path, FILE__MOUNTON); 2812 } 2813 2814 static int selinux_umount(struct vfsmount *mnt, int flags) 2815 { 2816 const struct cred *cred = current_cred(); 2817 2818 return superblock_has_perm(cred, mnt->mnt_sb, 2819 FILESYSTEM__UNMOUNT, NULL); 2820 } 2821 2822 /* inode security operations */ 2823 2824 static int selinux_inode_alloc_security(struct inode *inode) 2825 { 2826 return inode_alloc_security(inode); 2827 } 2828 2829 static void selinux_inode_free_security(struct inode *inode) 2830 { 2831 inode_free_security(inode); 2832 } 2833 2834 static int selinux_dentry_init_security(struct dentry *dentry, int mode, 2835 const struct qstr *name, void **ctx, 2836 u32 *ctxlen) 2837 { 2838 u32 newsid; 2839 int rc; 2840 2841 rc = selinux_determine_inode_label(current_security(), 2842 d_inode(dentry->d_parent), name, 2843 inode_mode_to_security_class(mode), 2844 &newsid); 2845 if (rc) 2846 return rc; 2847 2848 return security_sid_to_context(newsid, (char **)ctx, ctxlen); 2849 } 2850 2851 static int selinux_dentry_create_files_as(struct dentry *dentry, int mode, 2852 struct qstr *name, 2853 const struct cred *old, 2854 struct cred *new) 2855 { 2856 u32 newsid; 2857 int rc; 2858 struct task_security_struct *tsec; 2859 2860 rc = selinux_determine_inode_label(old->security, 2861 d_inode(dentry->d_parent), name, 2862 inode_mode_to_security_class(mode), 2863 &newsid); 2864 if (rc) 2865 return rc; 2866 2867 tsec = new->security; 2868 tsec->create_sid = newsid; 2869 return 0; 2870 } 2871 2872 static int selinux_inode_init_security(struct inode *inode, struct inode *dir, 2873 const struct qstr *qstr, 2874 const char **name, 2875 void **value, size_t *len) 2876 { 2877 const struct task_security_struct *tsec = current_security(); 2878 struct superblock_security_struct *sbsec; 2879 u32 sid, newsid, clen; 2880 int rc; 2881 char *context; 2882 2883 sbsec = dir->i_sb->s_security; 2884 2885 sid = tsec->sid; 2886 newsid = tsec->create_sid; 2887 2888 rc = selinux_determine_inode_label(current_security(), 2889 dir, qstr, 2890 inode_mode_to_security_class(inode->i_mode), 2891 &newsid); 2892 if (rc) 2893 return rc; 2894 2895 /* Possibly defer initialization to selinux_complete_init. */ 2896 if (sbsec->flags & SE_SBINITIALIZED) { 2897 struct inode_security_struct *isec = inode->i_security; 2898 isec->sclass = inode_mode_to_security_class(inode->i_mode); 2899 isec->sid = newsid; 2900 isec->initialized = LABEL_INITIALIZED; 2901 } 2902 2903 if (!ss_initialized || !(sbsec->flags & SBLABEL_MNT)) 2904 return -EOPNOTSUPP; 2905 2906 if (name) 2907 *name = XATTR_SELINUX_SUFFIX; 2908 2909 if (value && len) { 2910 rc = security_sid_to_context_force(newsid, &context, &clen); 2911 if (rc) 2912 return rc; 2913 *value = context; 2914 *len = clen; 2915 } 2916 2917 return 0; 2918 } 2919 2920 static int selinux_inode_create(struct inode *dir, struct dentry *dentry, umode_t mode) 2921 { 2922 return may_create(dir, dentry, SECCLASS_FILE); 2923 } 2924 2925 static int selinux_inode_link(struct dentry *old_dentry, struct inode *dir, struct dentry *new_dentry) 2926 { 2927 return may_link(dir, old_dentry, MAY_LINK); 2928 } 2929 2930 static int selinux_inode_unlink(struct inode *dir, struct dentry *dentry) 2931 { 2932 return may_link(dir, dentry, MAY_UNLINK); 2933 } 2934 2935 static int selinux_inode_symlink(struct inode *dir, struct dentry *dentry, const char *name) 2936 { 2937 return may_create(dir, dentry, SECCLASS_LNK_FILE); 2938 } 2939 2940 static int selinux_inode_mkdir(struct inode *dir, struct dentry *dentry, umode_t mask) 2941 { 2942 return may_create(dir, dentry, SECCLASS_DIR); 2943 } 2944 2945 static int selinux_inode_rmdir(struct inode *dir, struct dentry *dentry) 2946 { 2947 return may_link(dir, dentry, MAY_RMDIR); 2948 } 2949 2950 static int selinux_inode_mknod(struct inode *dir, struct dentry *dentry, umode_t mode, dev_t dev) 2951 { 2952 return may_create(dir, dentry, inode_mode_to_security_class(mode)); 2953 } 2954 2955 static int selinux_inode_rename(struct inode *old_inode, struct dentry *old_dentry, 2956 struct inode *new_inode, struct dentry *new_dentry) 2957 { 2958 return may_rename(old_inode, old_dentry, new_inode, new_dentry); 2959 } 2960 2961 static int selinux_inode_readlink(struct dentry *dentry) 2962 { 2963 const struct cred *cred = current_cred(); 2964 2965 return dentry_has_perm(cred, dentry, FILE__READ); 2966 } 2967 2968 static int selinux_inode_follow_link(struct dentry *dentry, struct inode *inode, 2969 bool rcu) 2970 { 2971 const struct cred *cred = current_cred(); 2972 struct common_audit_data ad; 2973 struct inode_security_struct *isec; 2974 u32 sid; 2975 2976 validate_creds(cred); 2977 2978 ad.type = LSM_AUDIT_DATA_DENTRY; 2979 ad.u.dentry = dentry; 2980 sid = cred_sid(cred); 2981 isec = inode_security_rcu(inode, rcu); 2982 if (IS_ERR(isec)) 2983 return PTR_ERR(isec); 2984 2985 return avc_has_perm_flags(sid, isec->sid, isec->sclass, FILE__READ, &ad, 2986 rcu ? MAY_NOT_BLOCK : 0); 2987 } 2988 2989 static noinline int audit_inode_permission(struct inode *inode, 2990 u32 perms, u32 audited, u32 denied, 2991 int result, 2992 unsigned flags) 2993 { 2994 struct common_audit_data ad; 2995 struct inode_security_struct *isec = inode->i_security; 2996 int rc; 2997 2998 ad.type = LSM_AUDIT_DATA_INODE; 2999 ad.u.inode = inode; 3000 3001 rc = slow_avc_audit(current_sid(), isec->sid, isec->sclass, perms, 3002 audited, denied, result, &ad, flags); 3003 if (rc) 3004 return rc; 3005 return 0; 3006 } 3007 3008 static int selinux_inode_permission(struct inode *inode, int mask) 3009 { 3010 const struct cred *cred = current_cred(); 3011 u32 perms; 3012 bool from_access; 3013 unsigned flags = mask & MAY_NOT_BLOCK; 3014 struct inode_security_struct *isec; 3015 u32 sid; 3016 struct av_decision avd; 3017 int rc, rc2; 3018 u32 audited, denied; 3019 3020 from_access = mask & MAY_ACCESS; 3021 mask &= (MAY_READ|MAY_WRITE|MAY_EXEC|MAY_APPEND); 3022 3023 /* No permission to check. Existence test. */ 3024 if (!mask) 3025 return 0; 3026 3027 validate_creds(cred); 3028 3029 if (unlikely(IS_PRIVATE(inode))) 3030 return 0; 3031 3032 perms = file_mask_to_av(inode->i_mode, mask); 3033 3034 sid = cred_sid(cred); 3035 isec = inode_security_rcu(inode, flags & MAY_NOT_BLOCK); 3036 if (IS_ERR(isec)) 3037 return PTR_ERR(isec); 3038 3039 rc = avc_has_perm_noaudit(sid, isec->sid, isec->sclass, perms, 0, &avd); 3040 audited = avc_audit_required(perms, &avd, rc, 3041 from_access ? FILE__AUDIT_ACCESS : 0, 3042 &denied); 3043 if (likely(!audited)) 3044 return rc; 3045 3046 rc2 = audit_inode_permission(inode, perms, audited, denied, rc, flags); 3047 if (rc2) 3048 return rc2; 3049 return rc; 3050 } 3051 3052 static int selinux_inode_setattr(struct dentry *dentry, struct iattr *iattr) 3053 { 3054 const struct cred *cred = current_cred(); 3055 unsigned int ia_valid = iattr->ia_valid; 3056 __u32 av = FILE__WRITE; 3057 3058 /* ATTR_FORCE is just used for ATTR_KILL_S[UG]ID. */ 3059 if (ia_valid & ATTR_FORCE) { 3060 ia_valid &= ~(ATTR_KILL_SUID | ATTR_KILL_SGID | ATTR_MODE | 3061 ATTR_FORCE); 3062 if (!ia_valid) 3063 return 0; 3064 } 3065 3066 if (ia_valid & (ATTR_MODE | ATTR_UID | ATTR_GID | 3067 ATTR_ATIME_SET | ATTR_MTIME_SET | ATTR_TIMES_SET)) 3068 return dentry_has_perm(cred, dentry, FILE__SETATTR); 3069 3070 if (selinux_policycap_openperm && (ia_valid & ATTR_SIZE) 3071 && !(ia_valid & ATTR_FILE)) 3072 av |= FILE__OPEN; 3073 3074 return dentry_has_perm(cred, dentry, av); 3075 } 3076 3077 static int selinux_inode_getattr(const struct path *path) 3078 { 3079 return path_has_perm(current_cred(), path, FILE__GETATTR); 3080 } 3081 3082 static int selinux_inode_setotherxattr(struct dentry *dentry, const char *name) 3083 { 3084 const struct cred *cred = current_cred(); 3085 3086 if (!strncmp(name, XATTR_SECURITY_PREFIX, 3087 sizeof XATTR_SECURITY_PREFIX - 1)) { 3088 if (!strcmp(name, XATTR_NAME_CAPS)) { 3089 if (!capable(CAP_SETFCAP)) 3090 return -EPERM; 3091 } else if (!capable(CAP_SYS_ADMIN)) { 3092 /* A different attribute in the security namespace. 3093 Restrict to administrator. */ 3094 return -EPERM; 3095 } 3096 } 3097 3098 /* Not an attribute we recognize, so just check the 3099 ordinary setattr permission. */ 3100 return dentry_has_perm(cred, dentry, FILE__SETATTR); 3101 } 3102 3103 static int selinux_inode_setxattr(struct dentry *dentry, const char *name, 3104 const void *value, size_t size, int flags) 3105 { 3106 struct inode *inode = d_backing_inode(dentry); 3107 struct inode_security_struct *isec; 3108 struct superblock_security_struct *sbsec; 3109 struct common_audit_data ad; 3110 u32 newsid, sid = current_sid(); 3111 int rc = 0; 3112 3113 if (strcmp(name, XATTR_NAME_SELINUX)) 3114 return selinux_inode_setotherxattr(dentry, name); 3115 3116 sbsec = inode->i_sb->s_security; 3117 if (!(sbsec->flags & SBLABEL_MNT)) 3118 return -EOPNOTSUPP; 3119 3120 if (!inode_owner_or_capable(inode)) 3121 return -EPERM; 3122 3123 ad.type = LSM_AUDIT_DATA_DENTRY; 3124 ad.u.dentry = dentry; 3125 3126 isec = backing_inode_security(dentry); 3127 rc = avc_has_perm(sid, isec->sid, isec->sclass, 3128 FILE__RELABELFROM, &ad); 3129 if (rc) 3130 return rc; 3131 3132 rc = security_context_to_sid(value, size, &newsid, GFP_KERNEL); 3133 if (rc == -EINVAL) { 3134 if (!capable(CAP_MAC_ADMIN)) { 3135 struct audit_buffer *ab; 3136 size_t audit_size; 3137 const char *str; 3138 3139 /* We strip a nul only if it is at the end, otherwise the 3140 * context contains a nul and we should audit that */ 3141 if (value) { 3142 str = value; 3143 if (str[size - 1] == '\0') 3144 audit_size = size - 1; 3145 else 3146 audit_size = size; 3147 } else { 3148 str = ""; 3149 audit_size = 0; 3150 } 3151 ab = audit_log_start(current->audit_context, GFP_ATOMIC, AUDIT_SELINUX_ERR); 3152 audit_log_format(ab, "op=setxattr invalid_context="); 3153 audit_log_n_untrustedstring(ab, value, audit_size); 3154 audit_log_end(ab); 3155 3156 return rc; 3157 } 3158 rc = security_context_to_sid_force(value, size, &newsid); 3159 } 3160 if (rc) 3161 return rc; 3162 3163 rc = avc_has_perm(sid, newsid, isec->sclass, 3164 FILE__RELABELTO, &ad); 3165 if (rc) 3166 return rc; 3167 3168 rc = security_validate_transition(isec->sid, newsid, sid, 3169 isec->sclass); 3170 if (rc) 3171 return rc; 3172 3173 return avc_has_perm(newsid, 3174 sbsec->sid, 3175 SECCLASS_FILESYSTEM, 3176 FILESYSTEM__ASSOCIATE, 3177 &ad); 3178 } 3179 3180 static void selinux_inode_post_setxattr(struct dentry *dentry, const char *name, 3181 const void *value, size_t size, 3182 int flags) 3183 { 3184 struct inode *inode = d_backing_inode(dentry); 3185 struct inode_security_struct *isec; 3186 u32 newsid; 3187 int rc; 3188 3189 if (strcmp(name, XATTR_NAME_SELINUX)) { 3190 /* Not an attribute we recognize, so nothing to do. */ 3191 return; 3192 } 3193 3194 rc = security_context_to_sid_force(value, size, &newsid); 3195 if (rc) { 3196 printk(KERN_ERR "SELinux: unable to map context to SID" 3197 "for (%s, %lu), rc=%d\n", 3198 inode->i_sb->s_id, inode->i_ino, -rc); 3199 return; 3200 } 3201 3202 isec = backing_inode_security(dentry); 3203 isec->sclass = inode_mode_to_security_class(inode->i_mode); 3204 isec->sid = newsid; 3205 isec->initialized = LABEL_INITIALIZED; 3206 3207 return; 3208 } 3209 3210 static int selinux_inode_getxattr(struct dentry *dentry, const char *name) 3211 { 3212 const struct cred *cred = current_cred(); 3213 3214 return dentry_has_perm(cred, dentry, FILE__GETATTR); 3215 } 3216 3217 static int selinux_inode_listxattr(struct dentry *dentry) 3218 { 3219 const struct cred *cred = current_cred(); 3220 3221 return dentry_has_perm(cred, dentry, FILE__GETATTR); 3222 } 3223 3224 static int selinux_inode_removexattr(struct dentry *dentry, const char *name) 3225 { 3226 if (strcmp(name, XATTR_NAME_SELINUX)) 3227 return selinux_inode_setotherxattr(dentry, name); 3228 3229 /* No one is allowed to remove a SELinux security label. 3230 You can change the label, but all data must be labeled. */ 3231 return -EACCES; 3232 } 3233 3234 /* 3235 * Copy the inode security context value to the user. 3236 * 3237 * Permission check is handled by selinux_inode_getxattr hook. 3238 */ 3239 static int selinux_inode_getsecurity(struct inode *inode, const char *name, void **buffer, bool alloc) 3240 { 3241 u32 size; 3242 int error; 3243 char *context = NULL; 3244 struct inode_security_struct *isec; 3245 3246 if (strcmp(name, XATTR_SELINUX_SUFFIX)) 3247 return -EOPNOTSUPP; 3248 3249 /* 3250 * If the caller has CAP_MAC_ADMIN, then get the raw context 3251 * value even if it is not defined by current policy; otherwise, 3252 * use the in-core value under current policy. 3253 * Use the non-auditing forms of the permission checks since 3254 * getxattr may be called by unprivileged processes commonly 3255 * and lack of permission just means that we fall back to the 3256 * in-core context value, not a denial. 3257 */ 3258 error = cap_capable(current_cred(), &init_user_ns, CAP_MAC_ADMIN, 3259 SECURITY_CAP_NOAUDIT); 3260 if (!error) 3261 error = cred_has_capability(current_cred(), CAP_MAC_ADMIN, 3262 SECURITY_CAP_NOAUDIT, true); 3263 isec = inode_security(inode); 3264 if (!error) 3265 error = security_sid_to_context_force(isec->sid, &context, 3266 &size); 3267 else 3268 error = security_sid_to_context(isec->sid, &context, &size); 3269 if (error) 3270 return error; 3271 error = size; 3272 if (alloc) { 3273 *buffer = context; 3274 goto out_nofree; 3275 } 3276 kfree(context); 3277 out_nofree: 3278 return error; 3279 } 3280 3281 static int selinux_inode_setsecurity(struct inode *inode, const char *name, 3282 const void *value, size_t size, int flags) 3283 { 3284 struct inode_security_struct *isec = inode_security_novalidate(inode); 3285 u32 newsid; 3286 int rc; 3287 3288 if (strcmp(name, XATTR_SELINUX_SUFFIX)) 3289 return -EOPNOTSUPP; 3290 3291 if (!value || !size) 3292 return -EACCES; 3293 3294 rc = security_context_to_sid(value, size, &newsid, GFP_KERNEL); 3295 if (rc) 3296 return rc; 3297 3298 isec->sclass = inode_mode_to_security_class(inode->i_mode); 3299 isec->sid = newsid; 3300 isec->initialized = LABEL_INITIALIZED; 3301 return 0; 3302 } 3303 3304 static int selinux_inode_listsecurity(struct inode *inode, char *buffer, size_t buffer_size) 3305 { 3306 const int len = sizeof(XATTR_NAME_SELINUX); 3307 if (buffer && len <= buffer_size) 3308 memcpy(buffer, XATTR_NAME_SELINUX, len); 3309 return len; 3310 } 3311 3312 static void selinux_inode_getsecid(struct inode *inode, u32 *secid) 3313 { 3314 struct inode_security_struct *isec = inode_security_novalidate(inode); 3315 *secid = isec->sid; 3316 } 3317 3318 static int selinux_inode_copy_up(struct dentry *src, struct cred **new) 3319 { 3320 u32 sid; 3321 struct task_security_struct *tsec; 3322 struct cred *new_creds = *new; 3323 3324 if (new_creds == NULL) { 3325 new_creds = prepare_creds(); 3326 if (!new_creds) 3327 return -ENOMEM; 3328 } 3329 3330 tsec = new_creds->security; 3331 /* Get label from overlay inode and set it in create_sid */ 3332 selinux_inode_getsecid(d_inode(src), &sid); 3333 tsec->create_sid = sid; 3334 *new = new_creds; 3335 return 0; 3336 } 3337 3338 static int selinux_inode_copy_up_xattr(const char *name) 3339 { 3340 /* The copy_up hook above sets the initial context on an inode, but we 3341 * don't then want to overwrite it by blindly copying all the lower 3342 * xattrs up. Instead, we have to filter out SELinux-related xattrs. 3343 */ 3344 if (strcmp(name, XATTR_NAME_SELINUX) == 0) 3345 return 1; /* Discard */ 3346 /* 3347 * Any other attribute apart from SELINUX is not claimed, supported 3348 * by selinux. 3349 */ 3350 return -EOPNOTSUPP; 3351 } 3352 3353 /* file security operations */ 3354 3355 static int selinux_revalidate_file_permission(struct file *file, int mask) 3356 { 3357 const struct cred *cred = current_cred(); 3358 struct inode *inode = file_inode(file); 3359 3360 /* file_mask_to_av won't add FILE__WRITE if MAY_APPEND is set */ 3361 if ((file->f_flags & O_APPEND) && (mask & MAY_WRITE)) 3362 mask |= MAY_APPEND; 3363 3364 return file_has_perm(cred, file, 3365 file_mask_to_av(inode->i_mode, mask)); 3366 } 3367 3368 static int selinux_file_permission(struct file *file, int mask) 3369 { 3370 struct inode *inode = file_inode(file); 3371 struct file_security_struct *fsec = file->f_security; 3372 struct inode_security_struct *isec; 3373 u32 sid = current_sid(); 3374 3375 if (!mask) 3376 /* No permission to check. Existence test. */ 3377 return 0; 3378 3379 isec = inode_security(inode); 3380 if (sid == fsec->sid && fsec->isid == isec->sid && 3381 fsec->pseqno == avc_policy_seqno()) 3382 /* No change since file_open check. */ 3383 return 0; 3384 3385 return selinux_revalidate_file_permission(file, mask); 3386 } 3387 3388 static int selinux_file_alloc_security(struct file *file) 3389 { 3390 return file_alloc_security(file); 3391 } 3392 3393 static void selinux_file_free_security(struct file *file) 3394 { 3395 file_free_security(file); 3396 } 3397 3398 /* 3399 * Check whether a task has the ioctl permission and cmd 3400 * operation to an inode. 3401 */ 3402 static int ioctl_has_perm(const struct cred *cred, struct file *file, 3403 u32 requested, u16 cmd) 3404 { 3405 struct common_audit_data ad; 3406 struct file_security_struct *fsec = file->f_security; 3407 struct inode *inode = file_inode(file); 3408 struct inode_security_struct *isec; 3409 struct lsm_ioctlop_audit ioctl; 3410 u32 ssid = cred_sid(cred); 3411 int rc; 3412 u8 driver = cmd >> 8; 3413 u8 xperm = cmd & 0xff; 3414 3415 ad.type = LSM_AUDIT_DATA_IOCTL_OP; 3416 ad.u.op = &ioctl; 3417 ad.u.op->cmd = cmd; 3418 ad.u.op->path = file->f_path; 3419 3420 if (ssid != fsec->sid) { 3421 rc = avc_has_perm(ssid, fsec->sid, 3422 SECCLASS_FD, 3423 FD__USE, 3424 &ad); 3425 if (rc) 3426 goto out; 3427 } 3428 3429 if (unlikely(IS_PRIVATE(inode))) 3430 return 0; 3431 3432 isec = inode_security(inode); 3433 rc = avc_has_extended_perms(ssid, isec->sid, isec->sclass, 3434 requested, driver, xperm, &ad); 3435 out: 3436 return rc; 3437 } 3438 3439 static int selinux_file_ioctl(struct file *file, unsigned int cmd, 3440 unsigned long arg) 3441 { 3442 const struct cred *cred = current_cred(); 3443 int error = 0; 3444 3445 switch (cmd) { 3446 case FIONREAD: 3447 /* fall through */ 3448 case FIBMAP: 3449 /* fall through */ 3450 case FIGETBSZ: 3451 /* fall through */ 3452 case FS_IOC_GETFLAGS: 3453 /* fall through */ 3454 case FS_IOC_GETVERSION: 3455 error = file_has_perm(cred, file, FILE__GETATTR); 3456 break; 3457 3458 case FS_IOC_SETFLAGS: 3459 /* fall through */ 3460 case FS_IOC_SETVERSION: 3461 error = file_has_perm(cred, file, FILE__SETATTR); 3462 break; 3463 3464 /* sys_ioctl() checks */ 3465 case FIONBIO: 3466 /* fall through */ 3467 case FIOASYNC: 3468 error = file_has_perm(cred, file, 0); 3469 break; 3470 3471 case KDSKBENT: 3472 case KDSKBSENT: 3473 error = cred_has_capability(cred, CAP_SYS_TTY_CONFIG, 3474 SECURITY_CAP_AUDIT, true); 3475 break; 3476 3477 /* default case assumes that the command will go 3478 * to the file's ioctl() function. 3479 */ 3480 default: 3481 error = ioctl_has_perm(cred, file, FILE__IOCTL, (u16) cmd); 3482 } 3483 return error; 3484 } 3485 3486 static int default_noexec; 3487 3488 static int file_map_prot_check(struct file *file, unsigned long prot, int shared) 3489 { 3490 const struct cred *cred = current_cred(); 3491 int rc = 0; 3492 3493 if (default_noexec && 3494 (prot & PROT_EXEC) && (!file || IS_PRIVATE(file_inode(file)) || 3495 (!shared && (prot & PROT_WRITE)))) { 3496 /* 3497 * We are making executable an anonymous mapping or a 3498 * private file mapping that will also be writable. 3499 * This has an additional check. 3500 */ 3501 rc = cred_has_perm(cred, cred, PROCESS__EXECMEM); 3502 if (rc) 3503 goto error; 3504 } 3505 3506 if (file) { 3507 /* read access is always possible with a mapping */ 3508 u32 av = FILE__READ; 3509 3510 /* write access only matters if the mapping is shared */ 3511 if (shared && (prot & PROT_WRITE)) 3512 av |= FILE__WRITE; 3513 3514 if (prot & PROT_EXEC) 3515 av |= FILE__EXECUTE; 3516 3517 return file_has_perm(cred, file, av); 3518 } 3519 3520 error: 3521 return rc; 3522 } 3523 3524 static int selinux_mmap_addr(unsigned long addr) 3525 { 3526 int rc = 0; 3527 3528 if (addr < CONFIG_LSM_MMAP_MIN_ADDR) { 3529 u32 sid = current_sid(); 3530 rc = avc_has_perm(sid, sid, SECCLASS_MEMPROTECT, 3531 MEMPROTECT__MMAP_ZERO, NULL); 3532 } 3533 3534 return rc; 3535 } 3536 3537 static int selinux_mmap_file(struct file *file, unsigned long reqprot, 3538 unsigned long prot, unsigned long flags) 3539 { 3540 if (selinux_checkreqprot) 3541 prot = reqprot; 3542 3543 return file_map_prot_check(file, prot, 3544 (flags & MAP_TYPE) == MAP_SHARED); 3545 } 3546 3547 static int selinux_file_mprotect(struct vm_area_struct *vma, 3548 unsigned long reqprot, 3549 unsigned long prot) 3550 { 3551 const struct cred *cred = current_cred(); 3552 3553 if (selinux_checkreqprot) 3554 prot = reqprot; 3555 3556 if (default_noexec && 3557 (prot & PROT_EXEC) && !(vma->vm_flags & VM_EXEC)) { 3558 int rc = 0; 3559 if (vma->vm_start >= vma->vm_mm->start_brk && 3560 vma->vm_end <= vma->vm_mm->brk) { 3561 rc = cred_has_perm(cred, cred, PROCESS__EXECHEAP); 3562 } else if (!vma->vm_file && 3563 ((vma->vm_start <= vma->vm_mm->start_stack && 3564 vma->vm_end >= vma->vm_mm->start_stack) || 3565 vma_is_stack_for_task(vma, current))) { 3566 rc = current_has_perm(current, PROCESS__EXECSTACK); 3567 } else if (vma->vm_file && vma->anon_vma) { 3568 /* 3569 * We are making executable a file mapping that has 3570 * had some COW done. Since pages might have been 3571 * written, check ability to execute the possibly 3572 * modified content. This typically should only 3573 * occur for text relocations. 3574 */ 3575 rc = file_has_perm(cred, vma->vm_file, FILE__EXECMOD); 3576 } 3577 if (rc) 3578 return rc; 3579 } 3580 3581 return file_map_prot_check(vma->vm_file, prot, vma->vm_flags&VM_SHARED); 3582 } 3583 3584 static int selinux_file_lock(struct file *file, unsigned int cmd) 3585 { 3586 const struct cred *cred = current_cred(); 3587 3588 return file_has_perm(cred, file, FILE__LOCK); 3589 } 3590 3591 static int selinux_file_fcntl(struct file *file, unsigned int cmd, 3592 unsigned long arg) 3593 { 3594 const struct cred *cred = current_cred(); 3595 int err = 0; 3596 3597 switch (cmd) { 3598 case F_SETFL: 3599 if ((file->f_flags & O_APPEND) && !(arg & O_APPEND)) { 3600 err = file_has_perm(cred, file, FILE__WRITE); 3601 break; 3602 } 3603 /* fall through */ 3604 case F_SETOWN: 3605 case F_SETSIG: 3606 case F_GETFL: 3607 case F_GETOWN: 3608 case F_GETSIG: 3609 case F_GETOWNER_UIDS: 3610 /* Just check FD__USE permission */ 3611 err = file_has_perm(cred, file, 0); 3612 break; 3613 case F_GETLK: 3614 case F_SETLK: 3615 case F_SETLKW: 3616 case F_OFD_GETLK: 3617 case F_OFD_SETLK: 3618 case F_OFD_SETLKW: 3619 #if BITS_PER_LONG == 32 3620 case F_GETLK64: 3621 case F_SETLK64: 3622 case F_SETLKW64: 3623 #endif 3624 err = file_has_perm(cred, file, FILE__LOCK); 3625 break; 3626 } 3627 3628 return err; 3629 } 3630 3631 static void selinux_file_set_fowner(struct file *file) 3632 { 3633 struct file_security_struct *fsec; 3634 3635 fsec = file->f_security; 3636 fsec->fown_sid = current_sid(); 3637 } 3638 3639 static int selinux_file_send_sigiotask(struct task_struct *tsk, 3640 struct fown_struct *fown, int signum) 3641 { 3642 struct file *file; 3643 u32 sid = task_sid(tsk); 3644 u32 perm; 3645 struct file_security_struct *fsec; 3646 3647 /* struct fown_struct is never outside the context of a struct file */ 3648 file = container_of(fown, struct file, f_owner); 3649 3650 fsec = file->f_security; 3651 3652 if (!signum) 3653 perm = signal_to_av(SIGIO); /* as per send_sigio_to_task */ 3654 else 3655 perm = signal_to_av(signum); 3656 3657 return avc_has_perm(fsec->fown_sid, sid, 3658 SECCLASS_PROCESS, perm, NULL); 3659 } 3660 3661 static int selinux_file_receive(struct file *file) 3662 { 3663 const struct cred *cred = current_cred(); 3664 3665 return file_has_perm(cred, file, file_to_av(file)); 3666 } 3667 3668 static int selinux_file_open(struct file *file, const struct cred *cred) 3669 { 3670 struct file_security_struct *fsec; 3671 struct inode_security_struct *isec; 3672 3673 fsec = file->f_security; 3674 isec = inode_security(file_inode(file)); 3675 /* 3676 * Save inode label and policy sequence number 3677 * at open-time so that selinux_file_permission 3678 * can determine whether revalidation is necessary. 3679 * Task label is already saved in the file security 3680 * struct as its SID. 3681 */ 3682 fsec->isid = isec->sid; 3683 fsec->pseqno = avc_policy_seqno(); 3684 /* 3685 * Since the inode label or policy seqno may have changed 3686 * between the selinux_inode_permission check and the saving 3687 * of state above, recheck that access is still permitted. 3688 * Otherwise, access might never be revalidated against the 3689 * new inode label or new policy. 3690 * This check is not redundant - do not remove. 3691 */ 3692 return file_path_has_perm(cred, file, open_file_to_av(file)); 3693 } 3694 3695 /* task security operations */ 3696 3697 static int selinux_task_create(unsigned long clone_flags) 3698 { 3699 return current_has_perm(current, PROCESS__FORK); 3700 } 3701 3702 /* 3703 * allocate the SELinux part of blank credentials 3704 */ 3705 static int selinux_cred_alloc_blank(struct cred *cred, gfp_t gfp) 3706 { 3707 struct task_security_struct *tsec; 3708 3709 tsec = kzalloc(sizeof(struct task_security_struct), gfp); 3710 if (!tsec) 3711 return -ENOMEM; 3712 3713 cred->security = tsec; 3714 return 0; 3715 } 3716 3717 /* 3718 * detach and free the LSM part of a set of credentials 3719 */ 3720 static void selinux_cred_free(struct cred *cred) 3721 { 3722 struct task_security_struct *tsec = cred->security; 3723 3724 /* 3725 * cred->security == NULL if security_cred_alloc_blank() or 3726 * security_prepare_creds() returned an error. 3727 */ 3728 BUG_ON(cred->security && (unsigned long) cred->security < PAGE_SIZE); 3729 cred->security = (void *) 0x7UL; 3730 kfree(tsec); 3731 } 3732 3733 /* 3734 * prepare a new set of credentials for modification 3735 */ 3736 static int selinux_cred_prepare(struct cred *new, const struct cred *old, 3737 gfp_t gfp) 3738 { 3739 const struct task_security_struct *old_tsec; 3740 struct task_security_struct *tsec; 3741 3742 old_tsec = old->security; 3743 3744 tsec = kmemdup(old_tsec, sizeof(struct task_security_struct), gfp); 3745 if (!tsec) 3746 return -ENOMEM; 3747 3748 new->security = tsec; 3749 return 0; 3750 } 3751 3752 /* 3753 * transfer the SELinux data to a blank set of creds 3754 */ 3755 static void selinux_cred_transfer(struct cred *new, const struct cred *old) 3756 { 3757 const struct task_security_struct *old_tsec = old->security; 3758 struct task_security_struct *tsec = new->security; 3759 3760 *tsec = *old_tsec; 3761 } 3762 3763 /* 3764 * set the security data for a kernel service 3765 * - all the creation contexts are set to unlabelled 3766 */ 3767 static int selinux_kernel_act_as(struct cred *new, u32 secid) 3768 { 3769 struct task_security_struct *tsec = new->security; 3770 u32 sid = current_sid(); 3771 int ret; 3772 3773 ret = avc_has_perm(sid, secid, 3774 SECCLASS_KERNEL_SERVICE, 3775 KERNEL_SERVICE__USE_AS_OVERRIDE, 3776 NULL); 3777 if (ret == 0) { 3778 tsec->sid = secid; 3779 tsec->create_sid = 0; 3780 tsec->keycreate_sid = 0; 3781 tsec->sockcreate_sid = 0; 3782 } 3783 return ret; 3784 } 3785 3786 /* 3787 * set the file creation context in a security record to the same as the 3788 * objective context of the specified inode 3789 */ 3790 static int selinux_kernel_create_files_as(struct cred *new, struct inode *inode) 3791 { 3792 struct inode_security_struct *isec = inode_security(inode); 3793 struct task_security_struct *tsec = new->security; 3794 u32 sid = current_sid(); 3795 int ret; 3796 3797 ret = avc_has_perm(sid, isec->sid, 3798 SECCLASS_KERNEL_SERVICE, 3799 KERNEL_SERVICE__CREATE_FILES_AS, 3800 NULL); 3801 3802 if (ret == 0) 3803 tsec->create_sid = isec->sid; 3804 return ret; 3805 } 3806 3807 static int selinux_kernel_module_request(char *kmod_name) 3808 { 3809 u32 sid; 3810 struct common_audit_data ad; 3811 3812 sid = task_sid(current); 3813 3814 ad.type = LSM_AUDIT_DATA_KMOD; 3815 ad.u.kmod_name = kmod_name; 3816 3817 return avc_has_perm(sid, SECINITSID_KERNEL, SECCLASS_SYSTEM, 3818 SYSTEM__MODULE_REQUEST, &ad); 3819 } 3820 3821 static int selinux_kernel_module_from_file(struct file *file) 3822 { 3823 struct common_audit_data ad; 3824 struct inode_security_struct *isec; 3825 struct file_security_struct *fsec; 3826 u32 sid = current_sid(); 3827 int rc; 3828 3829 /* init_module */ 3830 if (file == NULL) 3831 return avc_has_perm(sid, sid, SECCLASS_SYSTEM, 3832 SYSTEM__MODULE_LOAD, NULL); 3833 3834 /* finit_module */ 3835 3836 ad.type = LSM_AUDIT_DATA_FILE; 3837 ad.u.file = file; 3838 3839 fsec = file->f_security; 3840 if (sid != fsec->sid) { 3841 rc = avc_has_perm(sid, fsec->sid, SECCLASS_FD, FD__USE, &ad); 3842 if (rc) 3843 return rc; 3844 } 3845 3846 isec = inode_security(file_inode(file)); 3847 return avc_has_perm(sid, isec->sid, SECCLASS_SYSTEM, 3848 SYSTEM__MODULE_LOAD, &ad); 3849 } 3850 3851 static int selinux_kernel_read_file(struct file *file, 3852 enum kernel_read_file_id id) 3853 { 3854 int rc = 0; 3855 3856 switch (id) { 3857 case READING_MODULE: 3858 rc = selinux_kernel_module_from_file(file); 3859 break; 3860 default: 3861 break; 3862 } 3863 3864 return rc; 3865 } 3866 3867 static int selinux_task_setpgid(struct task_struct *p, pid_t pgid) 3868 { 3869 return current_has_perm(p, PROCESS__SETPGID); 3870 } 3871 3872 static int selinux_task_getpgid(struct task_struct *p) 3873 { 3874 return current_has_perm(p, PROCESS__GETPGID); 3875 } 3876 3877 static int selinux_task_getsid(struct task_struct *p) 3878 { 3879 return current_has_perm(p, PROCESS__GETSESSION); 3880 } 3881 3882 static void selinux_task_getsecid(struct task_struct *p, u32 *secid) 3883 { 3884 *secid = task_sid(p); 3885 } 3886 3887 static int selinux_task_setnice(struct task_struct *p, int nice) 3888 { 3889 return current_has_perm(p, PROCESS__SETSCHED); 3890 } 3891 3892 static int selinux_task_setioprio(struct task_struct *p, int ioprio) 3893 { 3894 return current_has_perm(p, PROCESS__SETSCHED); 3895 } 3896 3897 static int selinux_task_getioprio(struct task_struct *p) 3898 { 3899 return current_has_perm(p, PROCESS__GETSCHED); 3900 } 3901 3902 static int selinux_task_setrlimit(struct task_struct *p, unsigned int resource, 3903 struct rlimit *new_rlim) 3904 { 3905 struct rlimit *old_rlim = p->signal->rlim + resource; 3906 3907 /* Control the ability to change the hard limit (whether 3908 lowering or raising it), so that the hard limit can 3909 later be used as a safe reset point for the soft limit 3910 upon context transitions. See selinux_bprm_committing_creds. */ 3911 if (old_rlim->rlim_max != new_rlim->rlim_max) 3912 return current_has_perm(p, PROCESS__SETRLIMIT); 3913 3914 return 0; 3915 } 3916 3917 static int selinux_task_setscheduler(struct task_struct *p) 3918 { 3919 return current_has_perm(p, PROCESS__SETSCHED); 3920 } 3921 3922 static int selinux_task_getscheduler(struct task_struct *p) 3923 { 3924 return current_has_perm(p, PROCESS__GETSCHED); 3925 } 3926 3927 static int selinux_task_movememory(struct task_struct *p) 3928 { 3929 return current_has_perm(p, PROCESS__SETSCHED); 3930 } 3931 3932 static int selinux_task_kill(struct task_struct *p, struct siginfo *info, 3933 int sig, u32 secid) 3934 { 3935 u32 perm; 3936 int rc; 3937 3938 if (!sig) 3939 perm = PROCESS__SIGNULL; /* null signal; existence test */ 3940 else 3941 perm = signal_to_av(sig); 3942 if (secid) 3943 rc = avc_has_perm(secid, task_sid(p), 3944 SECCLASS_PROCESS, perm, NULL); 3945 else 3946 rc = current_has_perm(p, perm); 3947 return rc; 3948 } 3949 3950 static int selinux_task_wait(struct task_struct *p) 3951 { 3952 return task_has_perm(p, current, PROCESS__SIGCHLD); 3953 } 3954 3955 static void selinux_task_to_inode(struct task_struct *p, 3956 struct inode *inode) 3957 { 3958 struct inode_security_struct *isec = inode->i_security; 3959 u32 sid = task_sid(p); 3960 3961 isec->sid = sid; 3962 isec->initialized = LABEL_INITIALIZED; 3963 } 3964 3965 /* Returns error only if unable to parse addresses */ 3966 static int selinux_parse_skb_ipv4(struct sk_buff *skb, 3967 struct common_audit_data *ad, u8 *proto) 3968 { 3969 int offset, ihlen, ret = -EINVAL; 3970 struct iphdr _iph, *ih; 3971 3972 offset = skb_network_offset(skb); 3973 ih = skb_header_pointer(skb, offset, sizeof(_iph), &_iph); 3974 if (ih == NULL) 3975 goto out; 3976 3977 ihlen = ih->ihl * 4; 3978 if (ihlen < sizeof(_iph)) 3979 goto out; 3980 3981 ad->u.net->v4info.saddr = ih->saddr; 3982 ad->u.net->v4info.daddr = ih->daddr; 3983 ret = 0; 3984 3985 if (proto) 3986 *proto = ih->protocol; 3987 3988 switch (ih->protocol) { 3989 case IPPROTO_TCP: { 3990 struct tcphdr _tcph, *th; 3991 3992 if (ntohs(ih->frag_off) & IP_OFFSET) 3993 break; 3994 3995 offset += ihlen; 3996 th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph); 3997 if (th == NULL) 3998 break; 3999 4000 ad->u.net->sport = th->source; 4001 ad->u.net->dport = th->dest; 4002 break; 4003 } 4004 4005 case IPPROTO_UDP: { 4006 struct udphdr _udph, *uh; 4007 4008 if (ntohs(ih->frag_off) & IP_OFFSET) 4009 break; 4010 4011 offset += ihlen; 4012 uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph); 4013 if (uh == NULL) 4014 break; 4015 4016 ad->u.net->sport = uh->source; 4017 ad->u.net->dport = uh->dest; 4018 break; 4019 } 4020 4021 case IPPROTO_DCCP: { 4022 struct dccp_hdr _dccph, *dh; 4023 4024 if (ntohs(ih->frag_off) & IP_OFFSET) 4025 break; 4026 4027 offset += ihlen; 4028 dh = skb_header_pointer(skb, offset, sizeof(_dccph), &_dccph); 4029 if (dh == NULL) 4030 break; 4031 4032 ad->u.net->sport = dh->dccph_sport; 4033 ad->u.net->dport = dh->dccph_dport; 4034 break; 4035 } 4036 4037 default: 4038 break; 4039 } 4040 out: 4041 return ret; 4042 } 4043 4044 #if IS_ENABLED(CONFIG_IPV6) 4045 4046 /* Returns error only if unable to parse addresses */ 4047 static int selinux_parse_skb_ipv6(struct sk_buff *skb, 4048 struct common_audit_data *ad, u8 *proto) 4049 { 4050 u8 nexthdr; 4051 int ret = -EINVAL, offset; 4052 struct ipv6hdr _ipv6h, *ip6; 4053 __be16 frag_off; 4054 4055 offset = skb_network_offset(skb); 4056 ip6 = skb_header_pointer(skb, offset, sizeof(_ipv6h), &_ipv6h); 4057 if (ip6 == NULL) 4058 goto out; 4059 4060 ad->u.net->v6info.saddr = ip6->saddr; 4061 ad->u.net->v6info.daddr = ip6->daddr; 4062 ret = 0; 4063 4064 nexthdr = ip6->nexthdr; 4065 offset += sizeof(_ipv6h); 4066 offset = ipv6_skip_exthdr(skb, offset, &nexthdr, &frag_off); 4067 if (offset < 0) 4068 goto out; 4069 4070 if (proto) 4071 *proto = nexthdr; 4072 4073 switch (nexthdr) { 4074 case IPPROTO_TCP: { 4075 struct tcphdr _tcph, *th; 4076 4077 th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph); 4078 if (th == NULL) 4079 break; 4080 4081 ad->u.net->sport = th->source; 4082 ad->u.net->dport = th->dest; 4083 break; 4084 } 4085 4086 case IPPROTO_UDP: { 4087 struct udphdr _udph, *uh; 4088 4089 uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph); 4090 if (uh == NULL) 4091 break; 4092 4093 ad->u.net->sport = uh->source; 4094 ad->u.net->dport = uh->dest; 4095 break; 4096 } 4097 4098 case IPPROTO_DCCP: { 4099 struct dccp_hdr _dccph, *dh; 4100 4101 dh = skb_header_pointer(skb, offset, sizeof(_dccph), &_dccph); 4102 if (dh == NULL) 4103 break; 4104 4105 ad->u.net->sport = dh->dccph_sport; 4106 ad->u.net->dport = dh->dccph_dport; 4107 break; 4108 } 4109 4110 /* includes fragments */ 4111 default: 4112 break; 4113 } 4114 out: 4115 return ret; 4116 } 4117 4118 #endif /* IPV6 */ 4119 4120 static int selinux_parse_skb(struct sk_buff *skb, struct common_audit_data *ad, 4121 char **_addrp, int src, u8 *proto) 4122 { 4123 char *addrp; 4124 int ret; 4125 4126 switch (ad->u.net->family) { 4127 case PF_INET: 4128 ret = selinux_parse_skb_ipv4(skb, ad, proto); 4129 if (ret) 4130 goto parse_error; 4131 addrp = (char *)(src ? &ad->u.net->v4info.saddr : 4132 &ad->u.net->v4info.daddr); 4133 goto okay; 4134 4135 #if IS_ENABLED(CONFIG_IPV6) 4136 case PF_INET6: 4137 ret = selinux_parse_skb_ipv6(skb, ad, proto); 4138 if (ret) 4139 goto parse_error; 4140 addrp = (char *)(src ? &ad->u.net->v6info.saddr : 4141 &ad->u.net->v6info.daddr); 4142 goto okay; 4143 #endif /* IPV6 */ 4144 default: 4145 addrp = NULL; 4146 goto okay; 4147 } 4148 4149 parse_error: 4150 printk(KERN_WARNING 4151 "SELinux: failure in selinux_parse_skb()," 4152 " unable to parse packet\n"); 4153 return ret; 4154 4155 okay: 4156 if (_addrp) 4157 *_addrp = addrp; 4158 return 0; 4159 } 4160 4161 /** 4162 * selinux_skb_peerlbl_sid - Determine the peer label of a packet 4163 * @skb: the packet 4164 * @family: protocol family 4165 * @sid: the packet's peer label SID 4166 * 4167 * Description: 4168 * Check the various different forms of network peer labeling and determine 4169 * the peer label/SID for the packet; most of the magic actually occurs in 4170 * the security server function security_net_peersid_cmp(). The function 4171 * returns zero if the value in @sid is valid (although it may be SECSID_NULL) 4172 * or -EACCES if @sid is invalid due to inconsistencies with the different 4173 * peer labels. 4174 * 4175 */ 4176 static int selinux_skb_peerlbl_sid(struct sk_buff *skb, u16 family, u32 *sid) 4177 { 4178 int err; 4179 u32 xfrm_sid; 4180 u32 nlbl_sid; 4181 u32 nlbl_type; 4182 4183 err = selinux_xfrm_skb_sid(skb, &xfrm_sid); 4184 if (unlikely(err)) 4185 return -EACCES; 4186 err = selinux_netlbl_skbuff_getsid(skb, family, &nlbl_type, &nlbl_sid); 4187 if (unlikely(err)) 4188 return -EACCES; 4189 4190 err = security_net_peersid_resolve(nlbl_sid, nlbl_type, xfrm_sid, sid); 4191 if (unlikely(err)) { 4192 printk(KERN_WARNING 4193 "SELinux: failure in selinux_skb_peerlbl_sid()," 4194 " unable to determine packet's peer label\n"); 4195 return -EACCES; 4196 } 4197 4198 return 0; 4199 } 4200 4201 /** 4202 * selinux_conn_sid - Determine the child socket label for a connection 4203 * @sk_sid: the parent socket's SID 4204 * @skb_sid: the packet's SID 4205 * @conn_sid: the resulting connection SID 4206 * 4207 * If @skb_sid is valid then the user:role:type information from @sk_sid is 4208 * combined with the MLS information from @skb_sid in order to create 4209 * @conn_sid. If @skb_sid is not valid then then @conn_sid is simply a copy 4210 * of @sk_sid. Returns zero on success, negative values on failure. 4211 * 4212 */ 4213 static int selinux_conn_sid(u32 sk_sid, u32 skb_sid, u32 *conn_sid) 4214 { 4215 int err = 0; 4216 4217 if (skb_sid != SECSID_NULL) 4218 err = security_sid_mls_copy(sk_sid, skb_sid, conn_sid); 4219 else 4220 *conn_sid = sk_sid; 4221 4222 return err; 4223 } 4224 4225 /* socket security operations */ 4226 4227 static int socket_sockcreate_sid(const struct task_security_struct *tsec, 4228 u16 secclass, u32 *socksid) 4229 { 4230 if (tsec->sockcreate_sid > SECSID_NULL) { 4231 *socksid = tsec->sockcreate_sid; 4232 return 0; 4233 } 4234 4235 return security_transition_sid(tsec->sid, tsec->sid, secclass, NULL, 4236 socksid); 4237 } 4238 4239 static int sock_has_perm(struct task_struct *task, struct sock *sk, u32 perms) 4240 { 4241 struct sk_security_struct *sksec = sk->sk_security; 4242 struct common_audit_data ad; 4243 struct lsm_network_audit net = {0,}; 4244 u32 tsid = task_sid(task); 4245 4246 if (sksec->sid == SECINITSID_KERNEL) 4247 return 0; 4248 4249 ad.type = LSM_AUDIT_DATA_NET; 4250 ad.u.net = &net; 4251 ad.u.net->sk = sk; 4252 4253 return avc_has_perm(tsid, sksec->sid, sksec->sclass, perms, &ad); 4254 } 4255 4256 static int selinux_socket_create(int family, int type, 4257 int protocol, int kern) 4258 { 4259 const struct task_security_struct *tsec = current_security(); 4260 u32 newsid; 4261 u16 secclass; 4262 int rc; 4263 4264 if (kern) 4265 return 0; 4266 4267 secclass = socket_type_to_security_class(family, type, protocol); 4268 rc = socket_sockcreate_sid(tsec, secclass, &newsid); 4269 if (rc) 4270 return rc; 4271 4272 return avc_has_perm(tsec->sid, newsid, secclass, SOCKET__CREATE, NULL); 4273 } 4274 4275 static int selinux_socket_post_create(struct socket *sock, int family, 4276 int type, int protocol, int kern) 4277 { 4278 const struct task_security_struct *tsec = current_security(); 4279 struct inode_security_struct *isec = inode_security_novalidate(SOCK_INODE(sock)); 4280 struct sk_security_struct *sksec; 4281 int err = 0; 4282 4283 isec->sclass = socket_type_to_security_class(family, type, protocol); 4284 4285 if (kern) 4286 isec->sid = SECINITSID_KERNEL; 4287 else { 4288 err = socket_sockcreate_sid(tsec, isec->sclass, &(isec->sid)); 4289 if (err) 4290 return err; 4291 } 4292 4293 isec->initialized = LABEL_INITIALIZED; 4294 4295 if (sock->sk) { 4296 sksec = sock->sk->sk_security; 4297 sksec->sid = isec->sid; 4298 sksec->sclass = isec->sclass; 4299 err = selinux_netlbl_socket_post_create(sock->sk, family); 4300 } 4301 4302 return err; 4303 } 4304 4305 /* Range of port numbers used to automatically bind. 4306 Need to determine whether we should perform a name_bind 4307 permission check between the socket and the port number. */ 4308 4309 static int selinux_socket_bind(struct socket *sock, struct sockaddr *address, int addrlen) 4310 { 4311 struct sock *sk = sock->sk; 4312 u16 family; 4313 int err; 4314 4315 err = sock_has_perm(current, sk, SOCKET__BIND); 4316 if (err) 4317 goto out; 4318 4319 /* 4320 * If PF_INET or PF_INET6, check name_bind permission for the port. 4321 * Multiple address binding for SCTP is not supported yet: we just 4322 * check the first address now. 4323 */ 4324 family = sk->sk_family; 4325 if (family == PF_INET || family == PF_INET6) { 4326 char *addrp; 4327 struct sk_security_struct *sksec = sk->sk_security; 4328 struct common_audit_data ad; 4329 struct lsm_network_audit net = {0,}; 4330 struct sockaddr_in *addr4 = NULL; 4331 struct sockaddr_in6 *addr6 = NULL; 4332 unsigned short snum; 4333 u32 sid, node_perm; 4334 4335 if (family == PF_INET) { 4336 addr4 = (struct sockaddr_in *)address; 4337 snum = ntohs(addr4->sin_port); 4338 addrp = (char *)&addr4->sin_addr.s_addr; 4339 } else { 4340 addr6 = (struct sockaddr_in6 *)address; 4341 snum = ntohs(addr6->sin6_port); 4342 addrp = (char *)&addr6->sin6_addr.s6_addr; 4343 } 4344 4345 if (snum) { 4346 int low, high; 4347 4348 inet_get_local_port_range(sock_net(sk), &low, &high); 4349 4350 if (snum < max(PROT_SOCK, low) || snum > high) { 4351 err = sel_netport_sid(sk->sk_protocol, 4352 snum, &sid); 4353 if (err) 4354 goto out; 4355 ad.type = LSM_AUDIT_DATA_NET; 4356 ad.u.net = &net; 4357 ad.u.net->sport = htons(snum); 4358 ad.u.net->family = family; 4359 err = avc_has_perm(sksec->sid, sid, 4360 sksec->sclass, 4361 SOCKET__NAME_BIND, &ad); 4362 if (err) 4363 goto out; 4364 } 4365 } 4366 4367 switch (sksec->sclass) { 4368 case SECCLASS_TCP_SOCKET: 4369 node_perm = TCP_SOCKET__NODE_BIND; 4370 break; 4371 4372 case SECCLASS_UDP_SOCKET: 4373 node_perm = UDP_SOCKET__NODE_BIND; 4374 break; 4375 4376 case SECCLASS_DCCP_SOCKET: 4377 node_perm = DCCP_SOCKET__NODE_BIND; 4378 break; 4379 4380 default: 4381 node_perm = RAWIP_SOCKET__NODE_BIND; 4382 break; 4383 } 4384 4385 err = sel_netnode_sid(addrp, family, &sid); 4386 if (err) 4387 goto out; 4388 4389 ad.type = LSM_AUDIT_DATA_NET; 4390 ad.u.net = &net; 4391 ad.u.net->sport = htons(snum); 4392 ad.u.net->family = family; 4393 4394 if (family == PF_INET) 4395 ad.u.net->v4info.saddr = addr4->sin_addr.s_addr; 4396 else 4397 ad.u.net->v6info.saddr = addr6->sin6_addr; 4398 4399 err = avc_has_perm(sksec->sid, sid, 4400 sksec->sclass, node_perm, &ad); 4401 if (err) 4402 goto out; 4403 } 4404 out: 4405 return err; 4406 } 4407 4408 static int selinux_socket_connect(struct socket *sock, struct sockaddr *address, int addrlen) 4409 { 4410 struct sock *sk = sock->sk; 4411 struct sk_security_struct *sksec = sk->sk_security; 4412 int err; 4413 4414 err = sock_has_perm(current, sk, SOCKET__CONNECT); 4415 if (err) 4416 return err; 4417 4418 /* 4419 * If a TCP or DCCP socket, check name_connect permission for the port. 4420 */ 4421 if (sksec->sclass == SECCLASS_TCP_SOCKET || 4422 sksec->sclass == SECCLASS_DCCP_SOCKET) { 4423 struct common_audit_data ad; 4424 struct lsm_network_audit net = {0,}; 4425 struct sockaddr_in *addr4 = NULL; 4426 struct sockaddr_in6 *addr6 = NULL; 4427 unsigned short snum; 4428 u32 sid, perm; 4429 4430 if (sk->sk_family == PF_INET) { 4431 addr4 = (struct sockaddr_in *)address; 4432 if (addrlen < sizeof(struct sockaddr_in)) 4433 return -EINVAL; 4434 snum = ntohs(addr4->sin_port); 4435 } else { 4436 addr6 = (struct sockaddr_in6 *)address; 4437 if (addrlen < SIN6_LEN_RFC2133) 4438 return -EINVAL; 4439 snum = ntohs(addr6->sin6_port); 4440 } 4441 4442 err = sel_netport_sid(sk->sk_protocol, snum, &sid); 4443 if (err) 4444 goto out; 4445 4446 perm = (sksec->sclass == SECCLASS_TCP_SOCKET) ? 4447 TCP_SOCKET__NAME_CONNECT : DCCP_SOCKET__NAME_CONNECT; 4448 4449 ad.type = LSM_AUDIT_DATA_NET; 4450 ad.u.net = &net; 4451 ad.u.net->dport = htons(snum); 4452 ad.u.net->family = sk->sk_family; 4453 err = avc_has_perm(sksec->sid, sid, sksec->sclass, perm, &ad); 4454 if (err) 4455 goto out; 4456 } 4457 4458 err = selinux_netlbl_socket_connect(sk, address); 4459 4460 out: 4461 return err; 4462 } 4463 4464 static int selinux_socket_listen(struct socket *sock, int backlog) 4465 { 4466 return sock_has_perm(current, sock->sk, SOCKET__LISTEN); 4467 } 4468 4469 static int selinux_socket_accept(struct socket *sock, struct socket *newsock) 4470 { 4471 int err; 4472 struct inode_security_struct *isec; 4473 struct inode_security_struct *newisec; 4474 4475 err = sock_has_perm(current, sock->sk, SOCKET__ACCEPT); 4476 if (err) 4477 return err; 4478 4479 newisec = inode_security_novalidate(SOCK_INODE(newsock)); 4480 4481 isec = inode_security_novalidate(SOCK_INODE(sock)); 4482 newisec->sclass = isec->sclass; 4483 newisec->sid = isec->sid; 4484 newisec->initialized = LABEL_INITIALIZED; 4485 4486 return 0; 4487 } 4488 4489 static int selinux_socket_sendmsg(struct socket *sock, struct msghdr *msg, 4490 int size) 4491 { 4492 return sock_has_perm(current, sock->sk, SOCKET__WRITE); 4493 } 4494 4495 static int selinux_socket_recvmsg(struct socket *sock, struct msghdr *msg, 4496 int size, int flags) 4497 { 4498 return sock_has_perm(current, sock->sk, SOCKET__READ); 4499 } 4500 4501 static int selinux_socket_getsockname(struct socket *sock) 4502 { 4503 return sock_has_perm(current, sock->sk, SOCKET__GETATTR); 4504 } 4505 4506 static int selinux_socket_getpeername(struct socket *sock) 4507 { 4508 return sock_has_perm(current, sock->sk, SOCKET__GETATTR); 4509 } 4510 4511 static int selinux_socket_setsockopt(struct socket *sock, int level, int optname) 4512 { 4513 int err; 4514 4515 err = sock_has_perm(current, sock->sk, SOCKET__SETOPT); 4516 if (err) 4517 return err; 4518 4519 return selinux_netlbl_socket_setsockopt(sock, level, optname); 4520 } 4521 4522 static int selinux_socket_getsockopt(struct socket *sock, int level, 4523 int optname) 4524 { 4525 return sock_has_perm(current, sock->sk, SOCKET__GETOPT); 4526 } 4527 4528 static int selinux_socket_shutdown(struct socket *sock, int how) 4529 { 4530 return sock_has_perm(current, sock->sk, SOCKET__SHUTDOWN); 4531 } 4532 4533 static int selinux_socket_unix_stream_connect(struct sock *sock, 4534 struct sock *other, 4535 struct sock *newsk) 4536 { 4537 struct sk_security_struct *sksec_sock = sock->sk_security; 4538 struct sk_security_struct *sksec_other = other->sk_security; 4539 struct sk_security_struct *sksec_new = newsk->sk_security; 4540 struct common_audit_data ad; 4541 struct lsm_network_audit net = {0,}; 4542 int err; 4543 4544 ad.type = LSM_AUDIT_DATA_NET; 4545 ad.u.net = &net; 4546 ad.u.net->sk = other; 4547 4548 err = avc_has_perm(sksec_sock->sid, sksec_other->sid, 4549 sksec_other->sclass, 4550 UNIX_STREAM_SOCKET__CONNECTTO, &ad); 4551 if (err) 4552 return err; 4553 4554 /* server child socket */ 4555 sksec_new->peer_sid = sksec_sock->sid; 4556 err = security_sid_mls_copy(sksec_other->sid, sksec_sock->sid, 4557 &sksec_new->sid); 4558 if (err) 4559 return err; 4560 4561 /* connecting socket */ 4562 sksec_sock->peer_sid = sksec_new->sid; 4563 4564 return 0; 4565 } 4566 4567 static int selinux_socket_unix_may_send(struct socket *sock, 4568 struct socket *other) 4569 { 4570 struct sk_security_struct *ssec = sock->sk->sk_security; 4571 struct sk_security_struct *osec = other->sk->sk_security; 4572 struct common_audit_data ad; 4573 struct lsm_network_audit net = {0,}; 4574 4575 ad.type = LSM_AUDIT_DATA_NET; 4576 ad.u.net = &net; 4577 ad.u.net->sk = other->sk; 4578 4579 return avc_has_perm(ssec->sid, osec->sid, osec->sclass, SOCKET__SENDTO, 4580 &ad); 4581 } 4582 4583 static int selinux_inet_sys_rcv_skb(struct net *ns, int ifindex, 4584 char *addrp, u16 family, u32 peer_sid, 4585 struct common_audit_data *ad) 4586 { 4587 int err; 4588 u32 if_sid; 4589 u32 node_sid; 4590 4591 err = sel_netif_sid(ns, ifindex, &if_sid); 4592 if (err) 4593 return err; 4594 err = avc_has_perm(peer_sid, if_sid, 4595 SECCLASS_NETIF, NETIF__INGRESS, ad); 4596 if (err) 4597 return err; 4598 4599 err = sel_netnode_sid(addrp, family, &node_sid); 4600 if (err) 4601 return err; 4602 return avc_has_perm(peer_sid, node_sid, 4603 SECCLASS_NODE, NODE__RECVFROM, ad); 4604 } 4605 4606 static int selinux_sock_rcv_skb_compat(struct sock *sk, struct sk_buff *skb, 4607 u16 family) 4608 { 4609 int err = 0; 4610 struct sk_security_struct *sksec = sk->sk_security; 4611 u32 sk_sid = sksec->sid; 4612 struct common_audit_data ad; 4613 struct lsm_network_audit net = {0,}; 4614 char *addrp; 4615 4616 ad.type = LSM_AUDIT_DATA_NET; 4617 ad.u.net = &net; 4618 ad.u.net->netif = skb->skb_iif; 4619 ad.u.net->family = family; 4620 err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL); 4621 if (err) 4622 return err; 4623 4624 if (selinux_secmark_enabled()) { 4625 err = avc_has_perm(sk_sid, skb->secmark, SECCLASS_PACKET, 4626 PACKET__RECV, &ad); 4627 if (err) 4628 return err; 4629 } 4630 4631 err = selinux_netlbl_sock_rcv_skb(sksec, skb, family, &ad); 4632 if (err) 4633 return err; 4634 err = selinux_xfrm_sock_rcv_skb(sksec->sid, skb, &ad); 4635 4636 return err; 4637 } 4638 4639 static int selinux_socket_sock_rcv_skb(struct sock *sk, struct sk_buff *skb) 4640 { 4641 int err; 4642 struct sk_security_struct *sksec = sk->sk_security; 4643 u16 family = sk->sk_family; 4644 u32 sk_sid = sksec->sid; 4645 struct common_audit_data ad; 4646 struct lsm_network_audit net = {0,}; 4647 char *addrp; 4648 u8 secmark_active; 4649 u8 peerlbl_active; 4650 4651 if (family != PF_INET && family != PF_INET6) 4652 return 0; 4653 4654 /* Handle mapped IPv4 packets arriving via IPv6 sockets */ 4655 if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP)) 4656 family = PF_INET; 4657 4658 /* If any sort of compatibility mode is enabled then handoff processing 4659 * to the selinux_sock_rcv_skb_compat() function to deal with the 4660 * special handling. We do this in an attempt to keep this function 4661 * as fast and as clean as possible. */ 4662 if (!selinux_policycap_netpeer) 4663 return selinux_sock_rcv_skb_compat(sk, skb, family); 4664 4665 secmark_active = selinux_secmark_enabled(); 4666 peerlbl_active = selinux_peerlbl_enabled(); 4667 if (!secmark_active && !peerlbl_active) 4668 return 0; 4669 4670 ad.type = LSM_AUDIT_DATA_NET; 4671 ad.u.net = &net; 4672 ad.u.net->netif = skb->skb_iif; 4673 ad.u.net->family = family; 4674 err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL); 4675 if (err) 4676 return err; 4677 4678 if (peerlbl_active) { 4679 u32 peer_sid; 4680 4681 err = selinux_skb_peerlbl_sid(skb, family, &peer_sid); 4682 if (err) 4683 return err; 4684 err = selinux_inet_sys_rcv_skb(sock_net(sk), skb->skb_iif, 4685 addrp, family, peer_sid, &ad); 4686 if (err) { 4687 selinux_netlbl_err(skb, family, err, 0); 4688 return err; 4689 } 4690 err = avc_has_perm(sk_sid, peer_sid, SECCLASS_PEER, 4691 PEER__RECV, &ad); 4692 if (err) { 4693 selinux_netlbl_err(skb, family, err, 0); 4694 return err; 4695 } 4696 } 4697 4698 if (secmark_active) { 4699 err = avc_has_perm(sk_sid, skb->secmark, SECCLASS_PACKET, 4700 PACKET__RECV, &ad); 4701 if (err) 4702 return err; 4703 } 4704 4705 return err; 4706 } 4707 4708 static int selinux_socket_getpeersec_stream(struct socket *sock, char __user *optval, 4709 int __user *optlen, unsigned len) 4710 { 4711 int err = 0; 4712 char *scontext; 4713 u32 scontext_len; 4714 struct sk_security_struct *sksec = sock->sk->sk_security; 4715 u32 peer_sid = SECSID_NULL; 4716 4717 if (sksec->sclass == SECCLASS_UNIX_STREAM_SOCKET || 4718 sksec->sclass == SECCLASS_TCP_SOCKET) 4719 peer_sid = sksec->peer_sid; 4720 if (peer_sid == SECSID_NULL) 4721 return -ENOPROTOOPT; 4722 4723 err = security_sid_to_context(peer_sid, &scontext, &scontext_len); 4724 if (err) 4725 return err; 4726 4727 if (scontext_len > len) { 4728 err = -ERANGE; 4729 goto out_len; 4730 } 4731 4732 if (copy_to_user(optval, scontext, scontext_len)) 4733 err = -EFAULT; 4734 4735 out_len: 4736 if (put_user(scontext_len, optlen)) 4737 err = -EFAULT; 4738 kfree(scontext); 4739 return err; 4740 } 4741 4742 static int selinux_socket_getpeersec_dgram(struct socket *sock, struct sk_buff *skb, u32 *secid) 4743 { 4744 u32 peer_secid = SECSID_NULL; 4745 u16 family; 4746 struct inode_security_struct *isec; 4747 4748 if (skb && skb->protocol == htons(ETH_P_IP)) 4749 family = PF_INET; 4750 else if (skb && skb->protocol == htons(ETH_P_IPV6)) 4751 family = PF_INET6; 4752 else if (sock) 4753 family = sock->sk->sk_family; 4754 else 4755 goto out; 4756 4757 if (sock && family == PF_UNIX) { 4758 isec = inode_security_novalidate(SOCK_INODE(sock)); 4759 peer_secid = isec->sid; 4760 } else if (skb) 4761 selinux_skb_peerlbl_sid(skb, family, &peer_secid); 4762 4763 out: 4764 *secid = peer_secid; 4765 if (peer_secid == SECSID_NULL) 4766 return -EINVAL; 4767 return 0; 4768 } 4769 4770 static int selinux_sk_alloc_security(struct sock *sk, int family, gfp_t priority) 4771 { 4772 struct sk_security_struct *sksec; 4773 4774 sksec = kzalloc(sizeof(*sksec), priority); 4775 if (!sksec) 4776 return -ENOMEM; 4777 4778 sksec->peer_sid = SECINITSID_UNLABELED; 4779 sksec->sid = SECINITSID_UNLABELED; 4780 sksec->sclass = SECCLASS_SOCKET; 4781 selinux_netlbl_sk_security_reset(sksec); 4782 sk->sk_security = sksec; 4783 4784 return 0; 4785 } 4786 4787 static void selinux_sk_free_security(struct sock *sk) 4788 { 4789 struct sk_security_struct *sksec = sk->sk_security; 4790 4791 sk->sk_security = NULL; 4792 selinux_netlbl_sk_security_free(sksec); 4793 kfree(sksec); 4794 } 4795 4796 static void selinux_sk_clone_security(const struct sock *sk, struct sock *newsk) 4797 { 4798 struct sk_security_struct *sksec = sk->sk_security; 4799 struct sk_security_struct *newsksec = newsk->sk_security; 4800 4801 newsksec->sid = sksec->sid; 4802 newsksec->peer_sid = sksec->peer_sid; 4803 newsksec->sclass = sksec->sclass; 4804 4805 selinux_netlbl_sk_security_reset(newsksec); 4806 } 4807 4808 static void selinux_sk_getsecid(struct sock *sk, u32 *secid) 4809 { 4810 if (!sk) 4811 *secid = SECINITSID_ANY_SOCKET; 4812 else { 4813 struct sk_security_struct *sksec = sk->sk_security; 4814 4815 *secid = sksec->sid; 4816 } 4817 } 4818 4819 static void selinux_sock_graft(struct sock *sk, struct socket *parent) 4820 { 4821 struct inode_security_struct *isec = 4822 inode_security_novalidate(SOCK_INODE(parent)); 4823 struct sk_security_struct *sksec = sk->sk_security; 4824 4825 if (sk->sk_family == PF_INET || sk->sk_family == PF_INET6 || 4826 sk->sk_family == PF_UNIX) 4827 isec->sid = sksec->sid; 4828 sksec->sclass = isec->sclass; 4829 } 4830 4831 static int selinux_inet_conn_request(struct sock *sk, struct sk_buff *skb, 4832 struct request_sock *req) 4833 { 4834 struct sk_security_struct *sksec = sk->sk_security; 4835 int err; 4836 u16 family = req->rsk_ops->family; 4837 u32 connsid; 4838 u32 peersid; 4839 4840 err = selinux_skb_peerlbl_sid(skb, family, &peersid); 4841 if (err) 4842 return err; 4843 err = selinux_conn_sid(sksec->sid, peersid, &connsid); 4844 if (err) 4845 return err; 4846 req->secid = connsid; 4847 req->peer_secid = peersid; 4848 4849 return selinux_netlbl_inet_conn_request(req, family); 4850 } 4851 4852 static void selinux_inet_csk_clone(struct sock *newsk, 4853 const struct request_sock *req) 4854 { 4855 struct sk_security_struct *newsksec = newsk->sk_security; 4856 4857 newsksec->sid = req->secid; 4858 newsksec->peer_sid = req->peer_secid; 4859 /* NOTE: Ideally, we should also get the isec->sid for the 4860 new socket in sync, but we don't have the isec available yet. 4861 So we will wait until sock_graft to do it, by which 4862 time it will have been created and available. */ 4863 4864 /* We don't need to take any sort of lock here as we are the only 4865 * thread with access to newsksec */ 4866 selinux_netlbl_inet_csk_clone(newsk, req->rsk_ops->family); 4867 } 4868 4869 static void selinux_inet_conn_established(struct sock *sk, struct sk_buff *skb) 4870 { 4871 u16 family = sk->sk_family; 4872 struct sk_security_struct *sksec = sk->sk_security; 4873 4874 /* handle mapped IPv4 packets arriving via IPv6 sockets */ 4875 if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP)) 4876 family = PF_INET; 4877 4878 selinux_skb_peerlbl_sid(skb, family, &sksec->peer_sid); 4879 } 4880 4881 static int selinux_secmark_relabel_packet(u32 sid) 4882 { 4883 const struct task_security_struct *__tsec; 4884 u32 tsid; 4885 4886 __tsec = current_security(); 4887 tsid = __tsec->sid; 4888 4889 return avc_has_perm(tsid, sid, SECCLASS_PACKET, PACKET__RELABELTO, NULL); 4890 } 4891 4892 static void selinux_secmark_refcount_inc(void) 4893 { 4894 atomic_inc(&selinux_secmark_refcount); 4895 } 4896 4897 static void selinux_secmark_refcount_dec(void) 4898 { 4899 atomic_dec(&selinux_secmark_refcount); 4900 } 4901 4902 static void selinux_req_classify_flow(const struct request_sock *req, 4903 struct flowi *fl) 4904 { 4905 fl->flowi_secid = req->secid; 4906 } 4907 4908 static int selinux_tun_dev_alloc_security(void **security) 4909 { 4910 struct tun_security_struct *tunsec; 4911 4912 tunsec = kzalloc(sizeof(*tunsec), GFP_KERNEL); 4913 if (!tunsec) 4914 return -ENOMEM; 4915 tunsec->sid = current_sid(); 4916 4917 *security = tunsec; 4918 return 0; 4919 } 4920 4921 static void selinux_tun_dev_free_security(void *security) 4922 { 4923 kfree(security); 4924 } 4925 4926 static int selinux_tun_dev_create(void) 4927 { 4928 u32 sid = current_sid(); 4929 4930 /* we aren't taking into account the "sockcreate" SID since the socket 4931 * that is being created here is not a socket in the traditional sense, 4932 * instead it is a private sock, accessible only to the kernel, and 4933 * representing a wide range of network traffic spanning multiple 4934 * connections unlike traditional sockets - check the TUN driver to 4935 * get a better understanding of why this socket is special */ 4936 4937 return avc_has_perm(sid, sid, SECCLASS_TUN_SOCKET, TUN_SOCKET__CREATE, 4938 NULL); 4939 } 4940 4941 static int selinux_tun_dev_attach_queue(void *security) 4942 { 4943 struct tun_security_struct *tunsec = security; 4944 4945 return avc_has_perm(current_sid(), tunsec->sid, SECCLASS_TUN_SOCKET, 4946 TUN_SOCKET__ATTACH_QUEUE, NULL); 4947 } 4948 4949 static int selinux_tun_dev_attach(struct sock *sk, void *security) 4950 { 4951 struct tun_security_struct *tunsec = security; 4952 struct sk_security_struct *sksec = sk->sk_security; 4953 4954 /* we don't currently perform any NetLabel based labeling here and it 4955 * isn't clear that we would want to do so anyway; while we could apply 4956 * labeling without the support of the TUN user the resulting labeled 4957 * traffic from the other end of the connection would almost certainly 4958 * cause confusion to the TUN user that had no idea network labeling 4959 * protocols were being used */ 4960 4961 sksec->sid = tunsec->sid; 4962 sksec->sclass = SECCLASS_TUN_SOCKET; 4963 4964 return 0; 4965 } 4966 4967 static int selinux_tun_dev_open(void *security) 4968 { 4969 struct tun_security_struct *tunsec = security; 4970 u32 sid = current_sid(); 4971 int err; 4972 4973 err = avc_has_perm(sid, tunsec->sid, SECCLASS_TUN_SOCKET, 4974 TUN_SOCKET__RELABELFROM, NULL); 4975 if (err) 4976 return err; 4977 err = avc_has_perm(sid, sid, SECCLASS_TUN_SOCKET, 4978 TUN_SOCKET__RELABELTO, NULL); 4979 if (err) 4980 return err; 4981 tunsec->sid = sid; 4982 4983 return 0; 4984 } 4985 4986 static int selinux_nlmsg_perm(struct sock *sk, struct sk_buff *skb) 4987 { 4988 int err = 0; 4989 u32 perm; 4990 struct nlmsghdr *nlh; 4991 struct sk_security_struct *sksec = sk->sk_security; 4992 4993 if (skb->len < NLMSG_HDRLEN) { 4994 err = -EINVAL; 4995 goto out; 4996 } 4997 nlh = nlmsg_hdr(skb); 4998 4999 err = selinux_nlmsg_lookup(sksec->sclass, nlh->nlmsg_type, &perm); 5000 if (err) { 5001 if (err == -EINVAL) { 5002 pr_warn_ratelimited("SELinux: unrecognized netlink" 5003 " message: protocol=%hu nlmsg_type=%hu sclass=%s" 5004 " pig=%d comm=%s\n", 5005 sk->sk_protocol, nlh->nlmsg_type, 5006 secclass_map[sksec->sclass - 1].name, 5007 task_pid_nr(current), current->comm); 5008 if (!selinux_enforcing || security_get_allow_unknown()) 5009 err = 0; 5010 } 5011 5012 /* Ignore */ 5013 if (err == -ENOENT) 5014 err = 0; 5015 goto out; 5016 } 5017 5018 err = sock_has_perm(current, sk, perm); 5019 out: 5020 return err; 5021 } 5022 5023 #ifdef CONFIG_NETFILTER 5024 5025 static unsigned int selinux_ip_forward(struct sk_buff *skb, 5026 const struct net_device *indev, 5027 u16 family) 5028 { 5029 int err; 5030 char *addrp; 5031 u32 peer_sid; 5032 struct common_audit_data ad; 5033 struct lsm_network_audit net = {0,}; 5034 u8 secmark_active; 5035 u8 netlbl_active; 5036 u8 peerlbl_active; 5037 5038 if (!selinux_policycap_netpeer) 5039 return NF_ACCEPT; 5040 5041 secmark_active = selinux_secmark_enabled(); 5042 netlbl_active = netlbl_enabled(); 5043 peerlbl_active = selinux_peerlbl_enabled(); 5044 if (!secmark_active && !peerlbl_active) 5045 return NF_ACCEPT; 5046 5047 if (selinux_skb_peerlbl_sid(skb, family, &peer_sid) != 0) 5048 return NF_DROP; 5049 5050 ad.type = LSM_AUDIT_DATA_NET; 5051 ad.u.net = &net; 5052 ad.u.net->netif = indev->ifindex; 5053 ad.u.net->family = family; 5054 if (selinux_parse_skb(skb, &ad, &addrp, 1, NULL) != 0) 5055 return NF_DROP; 5056 5057 if (peerlbl_active) { 5058 err = selinux_inet_sys_rcv_skb(dev_net(indev), indev->ifindex, 5059 addrp, family, peer_sid, &ad); 5060 if (err) { 5061 selinux_netlbl_err(skb, family, err, 1); 5062 return NF_DROP; 5063 } 5064 } 5065 5066 if (secmark_active) 5067 if (avc_has_perm(peer_sid, skb->secmark, 5068 SECCLASS_PACKET, PACKET__FORWARD_IN, &ad)) 5069 return NF_DROP; 5070 5071 if (netlbl_active) 5072 /* we do this in the FORWARD path and not the POST_ROUTING 5073 * path because we want to make sure we apply the necessary 5074 * labeling before IPsec is applied so we can leverage AH 5075 * protection */ 5076 if (selinux_netlbl_skbuff_setsid(skb, family, peer_sid) != 0) 5077 return NF_DROP; 5078 5079 return NF_ACCEPT; 5080 } 5081 5082 static unsigned int selinux_ipv4_forward(void *priv, 5083 struct sk_buff *skb, 5084 const struct nf_hook_state *state) 5085 { 5086 return selinux_ip_forward(skb, state->in, PF_INET); 5087 } 5088 5089 #if IS_ENABLED(CONFIG_IPV6) 5090 static unsigned int selinux_ipv6_forward(void *priv, 5091 struct sk_buff *skb, 5092 const struct nf_hook_state *state) 5093 { 5094 return selinux_ip_forward(skb, state->in, PF_INET6); 5095 } 5096 #endif /* IPV6 */ 5097 5098 static unsigned int selinux_ip_output(struct sk_buff *skb, 5099 u16 family) 5100 { 5101 struct sock *sk; 5102 u32 sid; 5103 5104 if (!netlbl_enabled()) 5105 return NF_ACCEPT; 5106 5107 /* we do this in the LOCAL_OUT path and not the POST_ROUTING path 5108 * because we want to make sure we apply the necessary labeling 5109 * before IPsec is applied so we can leverage AH protection */ 5110 sk = skb->sk; 5111 if (sk) { 5112 struct sk_security_struct *sksec; 5113 5114 if (sk_listener(sk)) 5115 /* if the socket is the listening state then this 5116 * packet is a SYN-ACK packet which means it needs to 5117 * be labeled based on the connection/request_sock and 5118 * not the parent socket. unfortunately, we can't 5119 * lookup the request_sock yet as it isn't queued on 5120 * the parent socket until after the SYN-ACK is sent. 5121 * the "solution" is to simply pass the packet as-is 5122 * as any IP option based labeling should be copied 5123 * from the initial connection request (in the IP 5124 * layer). it is far from ideal, but until we get a 5125 * security label in the packet itself this is the 5126 * best we can do. */ 5127 return NF_ACCEPT; 5128 5129 /* standard practice, label using the parent socket */ 5130 sksec = sk->sk_security; 5131 sid = sksec->sid; 5132 } else 5133 sid = SECINITSID_KERNEL; 5134 if (selinux_netlbl_skbuff_setsid(skb, family, sid) != 0) 5135 return NF_DROP; 5136 5137 return NF_ACCEPT; 5138 } 5139 5140 static unsigned int selinux_ipv4_output(void *priv, 5141 struct sk_buff *skb, 5142 const struct nf_hook_state *state) 5143 { 5144 return selinux_ip_output(skb, PF_INET); 5145 } 5146 5147 #if IS_ENABLED(CONFIG_IPV6) 5148 static unsigned int selinux_ipv6_output(void *priv, 5149 struct sk_buff *skb, 5150 const struct nf_hook_state *state) 5151 { 5152 return selinux_ip_output(skb, PF_INET6); 5153 } 5154 #endif /* IPV6 */ 5155 5156 static unsigned int selinux_ip_postroute_compat(struct sk_buff *skb, 5157 int ifindex, 5158 u16 family) 5159 { 5160 struct sock *sk = skb_to_full_sk(skb); 5161 struct sk_security_struct *sksec; 5162 struct common_audit_data ad; 5163 struct lsm_network_audit net = {0,}; 5164 char *addrp; 5165 u8 proto; 5166 5167 if (sk == NULL) 5168 return NF_ACCEPT; 5169 sksec = sk->sk_security; 5170 5171 ad.type = LSM_AUDIT_DATA_NET; 5172 ad.u.net = &net; 5173 ad.u.net->netif = ifindex; 5174 ad.u.net->family = family; 5175 if (selinux_parse_skb(skb, &ad, &addrp, 0, &proto)) 5176 return NF_DROP; 5177 5178 if (selinux_secmark_enabled()) 5179 if (avc_has_perm(sksec->sid, skb->secmark, 5180 SECCLASS_PACKET, PACKET__SEND, &ad)) 5181 return NF_DROP_ERR(-ECONNREFUSED); 5182 5183 if (selinux_xfrm_postroute_last(sksec->sid, skb, &ad, proto)) 5184 return NF_DROP_ERR(-ECONNREFUSED); 5185 5186 return NF_ACCEPT; 5187 } 5188 5189 static unsigned int selinux_ip_postroute(struct sk_buff *skb, 5190 const struct net_device *outdev, 5191 u16 family) 5192 { 5193 u32 secmark_perm; 5194 u32 peer_sid; 5195 int ifindex = outdev->ifindex; 5196 struct sock *sk; 5197 struct common_audit_data ad; 5198 struct lsm_network_audit net = {0,}; 5199 char *addrp; 5200 u8 secmark_active; 5201 u8 peerlbl_active; 5202 5203 /* If any sort of compatibility mode is enabled then handoff processing 5204 * to the selinux_ip_postroute_compat() function to deal with the 5205 * special handling. We do this in an attempt to keep this function 5206 * as fast and as clean as possible. */ 5207 if (!selinux_policycap_netpeer) 5208 return selinux_ip_postroute_compat(skb, ifindex, family); 5209 5210 secmark_active = selinux_secmark_enabled(); 5211 peerlbl_active = selinux_peerlbl_enabled(); 5212 if (!secmark_active && !peerlbl_active) 5213 return NF_ACCEPT; 5214 5215 sk = skb_to_full_sk(skb); 5216 5217 #ifdef CONFIG_XFRM 5218 /* If skb->dst->xfrm is non-NULL then the packet is undergoing an IPsec 5219 * packet transformation so allow the packet to pass without any checks 5220 * since we'll have another chance to perform access control checks 5221 * when the packet is on it's final way out. 5222 * NOTE: there appear to be some IPv6 multicast cases where skb->dst 5223 * is NULL, in this case go ahead and apply access control. 5224 * NOTE: if this is a local socket (skb->sk != NULL) that is in the 5225 * TCP listening state we cannot wait until the XFRM processing 5226 * is done as we will miss out on the SA label if we do; 5227 * unfortunately, this means more work, but it is only once per 5228 * connection. */ 5229 if (skb_dst(skb) != NULL && skb_dst(skb)->xfrm != NULL && 5230 !(sk && sk_listener(sk))) 5231 return NF_ACCEPT; 5232 #endif 5233 5234 if (sk == NULL) { 5235 /* Without an associated socket the packet is either coming 5236 * from the kernel or it is being forwarded; check the packet 5237 * to determine which and if the packet is being forwarded 5238 * query the packet directly to determine the security label. */ 5239 if (skb->skb_iif) { 5240 secmark_perm = PACKET__FORWARD_OUT; 5241 if (selinux_skb_peerlbl_sid(skb, family, &peer_sid)) 5242 return NF_DROP; 5243 } else { 5244 secmark_perm = PACKET__SEND; 5245 peer_sid = SECINITSID_KERNEL; 5246 } 5247 } else if (sk_listener(sk)) { 5248 /* Locally generated packet but the associated socket is in the 5249 * listening state which means this is a SYN-ACK packet. In 5250 * this particular case the correct security label is assigned 5251 * to the connection/request_sock but unfortunately we can't 5252 * query the request_sock as it isn't queued on the parent 5253 * socket until after the SYN-ACK packet is sent; the only 5254 * viable choice is to regenerate the label like we do in 5255 * selinux_inet_conn_request(). See also selinux_ip_output() 5256 * for similar problems. */ 5257 u32 skb_sid; 5258 struct sk_security_struct *sksec; 5259 5260 sksec = sk->sk_security; 5261 if (selinux_skb_peerlbl_sid(skb, family, &skb_sid)) 5262 return NF_DROP; 5263 /* At this point, if the returned skb peerlbl is SECSID_NULL 5264 * and the packet has been through at least one XFRM 5265 * transformation then we must be dealing with the "final" 5266 * form of labeled IPsec packet; since we've already applied 5267 * all of our access controls on this packet we can safely 5268 * pass the packet. */ 5269 if (skb_sid == SECSID_NULL) { 5270 switch (family) { 5271 case PF_INET: 5272 if (IPCB(skb)->flags & IPSKB_XFRM_TRANSFORMED) 5273 return NF_ACCEPT; 5274 break; 5275 case PF_INET6: 5276 if (IP6CB(skb)->flags & IP6SKB_XFRM_TRANSFORMED) 5277 return NF_ACCEPT; 5278 break; 5279 default: 5280 return NF_DROP_ERR(-ECONNREFUSED); 5281 } 5282 } 5283 if (selinux_conn_sid(sksec->sid, skb_sid, &peer_sid)) 5284 return NF_DROP; 5285 secmark_perm = PACKET__SEND; 5286 } else { 5287 /* Locally generated packet, fetch the security label from the 5288 * associated socket. */ 5289 struct sk_security_struct *sksec = sk->sk_security; 5290 peer_sid = sksec->sid; 5291 secmark_perm = PACKET__SEND; 5292 } 5293 5294 ad.type = LSM_AUDIT_DATA_NET; 5295 ad.u.net = &net; 5296 ad.u.net->netif = ifindex; 5297 ad.u.net->family = family; 5298 if (selinux_parse_skb(skb, &ad, &addrp, 0, NULL)) 5299 return NF_DROP; 5300 5301 if (secmark_active) 5302 if (avc_has_perm(peer_sid, skb->secmark, 5303 SECCLASS_PACKET, secmark_perm, &ad)) 5304 return NF_DROP_ERR(-ECONNREFUSED); 5305 5306 if (peerlbl_active) { 5307 u32 if_sid; 5308 u32 node_sid; 5309 5310 if (sel_netif_sid(dev_net(outdev), ifindex, &if_sid)) 5311 return NF_DROP; 5312 if (avc_has_perm(peer_sid, if_sid, 5313 SECCLASS_NETIF, NETIF__EGRESS, &ad)) 5314 return NF_DROP_ERR(-ECONNREFUSED); 5315 5316 if (sel_netnode_sid(addrp, family, &node_sid)) 5317 return NF_DROP; 5318 if (avc_has_perm(peer_sid, node_sid, 5319 SECCLASS_NODE, NODE__SENDTO, &ad)) 5320 return NF_DROP_ERR(-ECONNREFUSED); 5321 } 5322 5323 return NF_ACCEPT; 5324 } 5325 5326 static unsigned int selinux_ipv4_postroute(void *priv, 5327 struct sk_buff *skb, 5328 const struct nf_hook_state *state) 5329 { 5330 return selinux_ip_postroute(skb, state->out, PF_INET); 5331 } 5332 5333 #if IS_ENABLED(CONFIG_IPV6) 5334 static unsigned int selinux_ipv6_postroute(void *priv, 5335 struct sk_buff *skb, 5336 const struct nf_hook_state *state) 5337 { 5338 return selinux_ip_postroute(skb, state->out, PF_INET6); 5339 } 5340 #endif /* IPV6 */ 5341 5342 #endif /* CONFIG_NETFILTER */ 5343 5344 static int selinux_netlink_send(struct sock *sk, struct sk_buff *skb) 5345 { 5346 return selinux_nlmsg_perm(sk, skb); 5347 } 5348 5349 static int ipc_alloc_security(struct task_struct *task, 5350 struct kern_ipc_perm *perm, 5351 u16 sclass) 5352 { 5353 struct ipc_security_struct *isec; 5354 u32 sid; 5355 5356 isec = kzalloc(sizeof(struct ipc_security_struct), GFP_KERNEL); 5357 if (!isec) 5358 return -ENOMEM; 5359 5360 sid = task_sid(task); 5361 isec->sclass = sclass; 5362 isec->sid = sid; 5363 perm->security = isec; 5364 5365 return 0; 5366 } 5367 5368 static void ipc_free_security(struct kern_ipc_perm *perm) 5369 { 5370 struct ipc_security_struct *isec = perm->security; 5371 perm->security = NULL; 5372 kfree(isec); 5373 } 5374 5375 static int msg_msg_alloc_security(struct msg_msg *msg) 5376 { 5377 struct msg_security_struct *msec; 5378 5379 msec = kzalloc(sizeof(struct msg_security_struct), GFP_KERNEL); 5380 if (!msec) 5381 return -ENOMEM; 5382 5383 msec->sid = SECINITSID_UNLABELED; 5384 msg->security = msec; 5385 5386 return 0; 5387 } 5388 5389 static void msg_msg_free_security(struct msg_msg *msg) 5390 { 5391 struct msg_security_struct *msec = msg->security; 5392 5393 msg->security = NULL; 5394 kfree(msec); 5395 } 5396 5397 static int ipc_has_perm(struct kern_ipc_perm *ipc_perms, 5398 u32 perms) 5399 { 5400 struct ipc_security_struct *isec; 5401 struct common_audit_data ad; 5402 u32 sid = current_sid(); 5403 5404 isec = ipc_perms->security; 5405 5406 ad.type = LSM_AUDIT_DATA_IPC; 5407 ad.u.ipc_id = ipc_perms->key; 5408 5409 return avc_has_perm(sid, isec->sid, isec->sclass, perms, &ad); 5410 } 5411 5412 static int selinux_msg_msg_alloc_security(struct msg_msg *msg) 5413 { 5414 return msg_msg_alloc_security(msg); 5415 } 5416 5417 static void selinux_msg_msg_free_security(struct msg_msg *msg) 5418 { 5419 msg_msg_free_security(msg); 5420 } 5421 5422 /* message queue security operations */ 5423 static int selinux_msg_queue_alloc_security(struct msg_queue *msq) 5424 { 5425 struct ipc_security_struct *isec; 5426 struct common_audit_data ad; 5427 u32 sid = current_sid(); 5428 int rc; 5429 5430 rc = ipc_alloc_security(current, &msq->q_perm, SECCLASS_MSGQ); 5431 if (rc) 5432 return rc; 5433 5434 isec = msq->q_perm.security; 5435 5436 ad.type = LSM_AUDIT_DATA_IPC; 5437 ad.u.ipc_id = msq->q_perm.key; 5438 5439 rc = avc_has_perm(sid, isec->sid, SECCLASS_MSGQ, 5440 MSGQ__CREATE, &ad); 5441 if (rc) { 5442 ipc_free_security(&msq->q_perm); 5443 return rc; 5444 } 5445 return 0; 5446 } 5447 5448 static void selinux_msg_queue_free_security(struct msg_queue *msq) 5449 { 5450 ipc_free_security(&msq->q_perm); 5451 } 5452 5453 static int selinux_msg_queue_associate(struct msg_queue *msq, int msqflg) 5454 { 5455 struct ipc_security_struct *isec; 5456 struct common_audit_data ad; 5457 u32 sid = current_sid(); 5458 5459 isec = msq->q_perm.security; 5460 5461 ad.type = LSM_AUDIT_DATA_IPC; 5462 ad.u.ipc_id = msq->q_perm.key; 5463 5464 return avc_has_perm(sid, isec->sid, SECCLASS_MSGQ, 5465 MSGQ__ASSOCIATE, &ad); 5466 } 5467 5468 static int selinux_msg_queue_msgctl(struct msg_queue *msq, int cmd) 5469 { 5470 int err; 5471 int perms; 5472 5473 switch (cmd) { 5474 case IPC_INFO: 5475 case MSG_INFO: 5476 /* No specific object, just general system-wide information. */ 5477 return task_has_system(current, SYSTEM__IPC_INFO); 5478 case IPC_STAT: 5479 case MSG_STAT: 5480 perms = MSGQ__GETATTR | MSGQ__ASSOCIATE; 5481 break; 5482 case IPC_SET: 5483 perms = MSGQ__SETATTR; 5484 break; 5485 case IPC_RMID: 5486 perms = MSGQ__DESTROY; 5487 break; 5488 default: 5489 return 0; 5490 } 5491 5492 err = ipc_has_perm(&msq->q_perm, perms); 5493 return err; 5494 } 5495 5496 static int selinux_msg_queue_msgsnd(struct msg_queue *msq, struct msg_msg *msg, int msqflg) 5497 { 5498 struct ipc_security_struct *isec; 5499 struct msg_security_struct *msec; 5500 struct common_audit_data ad; 5501 u32 sid = current_sid(); 5502 int rc; 5503 5504 isec = msq->q_perm.security; 5505 msec = msg->security; 5506 5507 /* 5508 * First time through, need to assign label to the message 5509 */ 5510 if (msec->sid == SECINITSID_UNLABELED) { 5511 /* 5512 * Compute new sid based on current process and 5513 * message queue this message will be stored in 5514 */ 5515 rc = security_transition_sid(sid, isec->sid, SECCLASS_MSG, 5516 NULL, &msec->sid); 5517 if (rc) 5518 return rc; 5519 } 5520 5521 ad.type = LSM_AUDIT_DATA_IPC; 5522 ad.u.ipc_id = msq->q_perm.key; 5523 5524 /* Can this process write to the queue? */ 5525 rc = avc_has_perm(sid, isec->sid, SECCLASS_MSGQ, 5526 MSGQ__WRITE, &ad); 5527 if (!rc) 5528 /* Can this process send the message */ 5529 rc = avc_has_perm(sid, msec->sid, SECCLASS_MSG, 5530 MSG__SEND, &ad); 5531 if (!rc) 5532 /* Can the message be put in the queue? */ 5533 rc = avc_has_perm(msec->sid, isec->sid, SECCLASS_MSGQ, 5534 MSGQ__ENQUEUE, &ad); 5535 5536 return rc; 5537 } 5538 5539 static int selinux_msg_queue_msgrcv(struct msg_queue *msq, struct msg_msg *msg, 5540 struct task_struct *target, 5541 long type, int mode) 5542 { 5543 struct ipc_security_struct *isec; 5544 struct msg_security_struct *msec; 5545 struct common_audit_data ad; 5546 u32 sid = task_sid(target); 5547 int rc; 5548 5549 isec = msq->q_perm.security; 5550 msec = msg->security; 5551 5552 ad.type = LSM_AUDIT_DATA_IPC; 5553 ad.u.ipc_id = msq->q_perm.key; 5554 5555 rc = avc_has_perm(sid, isec->sid, 5556 SECCLASS_MSGQ, MSGQ__READ, &ad); 5557 if (!rc) 5558 rc = avc_has_perm(sid, msec->sid, 5559 SECCLASS_MSG, MSG__RECEIVE, &ad); 5560 return rc; 5561 } 5562 5563 /* Shared Memory security operations */ 5564 static int selinux_shm_alloc_security(struct shmid_kernel *shp) 5565 { 5566 struct ipc_security_struct *isec; 5567 struct common_audit_data ad; 5568 u32 sid = current_sid(); 5569 int rc; 5570 5571 rc = ipc_alloc_security(current, &shp->shm_perm, SECCLASS_SHM); 5572 if (rc) 5573 return rc; 5574 5575 isec = shp->shm_perm.security; 5576 5577 ad.type = LSM_AUDIT_DATA_IPC; 5578 ad.u.ipc_id = shp->shm_perm.key; 5579 5580 rc = avc_has_perm(sid, isec->sid, SECCLASS_SHM, 5581 SHM__CREATE, &ad); 5582 if (rc) { 5583 ipc_free_security(&shp->shm_perm); 5584 return rc; 5585 } 5586 return 0; 5587 } 5588 5589 static void selinux_shm_free_security(struct shmid_kernel *shp) 5590 { 5591 ipc_free_security(&shp->shm_perm); 5592 } 5593 5594 static int selinux_shm_associate(struct shmid_kernel *shp, int shmflg) 5595 { 5596 struct ipc_security_struct *isec; 5597 struct common_audit_data ad; 5598 u32 sid = current_sid(); 5599 5600 isec = shp->shm_perm.security; 5601 5602 ad.type = LSM_AUDIT_DATA_IPC; 5603 ad.u.ipc_id = shp->shm_perm.key; 5604 5605 return avc_has_perm(sid, isec->sid, SECCLASS_SHM, 5606 SHM__ASSOCIATE, &ad); 5607 } 5608 5609 /* Note, at this point, shp is locked down */ 5610 static int selinux_shm_shmctl(struct shmid_kernel *shp, int cmd) 5611 { 5612 int perms; 5613 int err; 5614 5615 switch (cmd) { 5616 case IPC_INFO: 5617 case SHM_INFO: 5618 /* No specific object, just general system-wide information. */ 5619 return task_has_system(current, SYSTEM__IPC_INFO); 5620 case IPC_STAT: 5621 case SHM_STAT: 5622 perms = SHM__GETATTR | SHM__ASSOCIATE; 5623 break; 5624 case IPC_SET: 5625 perms = SHM__SETATTR; 5626 break; 5627 case SHM_LOCK: 5628 case SHM_UNLOCK: 5629 perms = SHM__LOCK; 5630 break; 5631 case IPC_RMID: 5632 perms = SHM__DESTROY; 5633 break; 5634 default: 5635 return 0; 5636 } 5637 5638 err = ipc_has_perm(&shp->shm_perm, perms); 5639 return err; 5640 } 5641 5642 static int selinux_shm_shmat(struct shmid_kernel *shp, 5643 char __user *shmaddr, int shmflg) 5644 { 5645 u32 perms; 5646 5647 if (shmflg & SHM_RDONLY) 5648 perms = SHM__READ; 5649 else 5650 perms = SHM__READ | SHM__WRITE; 5651 5652 return ipc_has_perm(&shp->shm_perm, perms); 5653 } 5654 5655 /* Semaphore security operations */ 5656 static int selinux_sem_alloc_security(struct sem_array *sma) 5657 { 5658 struct ipc_security_struct *isec; 5659 struct common_audit_data ad; 5660 u32 sid = current_sid(); 5661 int rc; 5662 5663 rc = ipc_alloc_security(current, &sma->sem_perm, SECCLASS_SEM); 5664 if (rc) 5665 return rc; 5666 5667 isec = sma->sem_perm.security; 5668 5669 ad.type = LSM_AUDIT_DATA_IPC; 5670 ad.u.ipc_id = sma->sem_perm.key; 5671 5672 rc = avc_has_perm(sid, isec->sid, SECCLASS_SEM, 5673 SEM__CREATE, &ad); 5674 if (rc) { 5675 ipc_free_security(&sma->sem_perm); 5676 return rc; 5677 } 5678 return 0; 5679 } 5680 5681 static void selinux_sem_free_security(struct sem_array *sma) 5682 { 5683 ipc_free_security(&sma->sem_perm); 5684 } 5685 5686 static int selinux_sem_associate(struct sem_array *sma, int semflg) 5687 { 5688 struct ipc_security_struct *isec; 5689 struct common_audit_data ad; 5690 u32 sid = current_sid(); 5691 5692 isec = sma->sem_perm.security; 5693 5694 ad.type = LSM_AUDIT_DATA_IPC; 5695 ad.u.ipc_id = sma->sem_perm.key; 5696 5697 return avc_has_perm(sid, isec->sid, SECCLASS_SEM, 5698 SEM__ASSOCIATE, &ad); 5699 } 5700 5701 /* Note, at this point, sma is locked down */ 5702 static int selinux_sem_semctl(struct sem_array *sma, int cmd) 5703 { 5704 int err; 5705 u32 perms; 5706 5707 switch (cmd) { 5708 case IPC_INFO: 5709 case SEM_INFO: 5710 /* No specific object, just general system-wide information. */ 5711 return task_has_system(current, SYSTEM__IPC_INFO); 5712 case GETPID: 5713 case GETNCNT: 5714 case GETZCNT: 5715 perms = SEM__GETATTR; 5716 break; 5717 case GETVAL: 5718 case GETALL: 5719 perms = SEM__READ; 5720 break; 5721 case SETVAL: 5722 case SETALL: 5723 perms = SEM__WRITE; 5724 break; 5725 case IPC_RMID: 5726 perms = SEM__DESTROY; 5727 break; 5728 case IPC_SET: 5729 perms = SEM__SETATTR; 5730 break; 5731 case IPC_STAT: 5732 case SEM_STAT: 5733 perms = SEM__GETATTR | SEM__ASSOCIATE; 5734 break; 5735 default: 5736 return 0; 5737 } 5738 5739 err = ipc_has_perm(&sma->sem_perm, perms); 5740 return err; 5741 } 5742 5743 static int selinux_sem_semop(struct sem_array *sma, 5744 struct sembuf *sops, unsigned nsops, int alter) 5745 { 5746 u32 perms; 5747 5748 if (alter) 5749 perms = SEM__READ | SEM__WRITE; 5750 else 5751 perms = SEM__READ; 5752 5753 return ipc_has_perm(&sma->sem_perm, perms); 5754 } 5755 5756 static int selinux_ipc_permission(struct kern_ipc_perm *ipcp, short flag) 5757 { 5758 u32 av = 0; 5759 5760 av = 0; 5761 if (flag & S_IRUGO) 5762 av |= IPC__UNIX_READ; 5763 if (flag & S_IWUGO) 5764 av |= IPC__UNIX_WRITE; 5765 5766 if (av == 0) 5767 return 0; 5768 5769 return ipc_has_perm(ipcp, av); 5770 } 5771 5772 static void selinux_ipc_getsecid(struct kern_ipc_perm *ipcp, u32 *secid) 5773 { 5774 struct ipc_security_struct *isec = ipcp->security; 5775 *secid = isec->sid; 5776 } 5777 5778 static void selinux_d_instantiate(struct dentry *dentry, struct inode *inode) 5779 { 5780 if (inode) 5781 inode_doinit_with_dentry(inode, dentry); 5782 } 5783 5784 static int selinux_getprocattr(struct task_struct *p, 5785 char *name, char **value) 5786 { 5787 const struct task_security_struct *__tsec; 5788 u32 sid; 5789 int error; 5790 unsigned len; 5791 5792 if (current != p) { 5793 error = current_has_perm(p, PROCESS__GETATTR); 5794 if (error) 5795 return error; 5796 } 5797 5798 rcu_read_lock(); 5799 __tsec = __task_cred(p)->security; 5800 5801 if (!strcmp(name, "current")) 5802 sid = __tsec->sid; 5803 else if (!strcmp(name, "prev")) 5804 sid = __tsec->osid; 5805 else if (!strcmp(name, "exec")) 5806 sid = __tsec->exec_sid; 5807 else if (!strcmp(name, "fscreate")) 5808 sid = __tsec->create_sid; 5809 else if (!strcmp(name, "keycreate")) 5810 sid = __tsec->keycreate_sid; 5811 else if (!strcmp(name, "sockcreate")) 5812 sid = __tsec->sockcreate_sid; 5813 else 5814 goto invalid; 5815 rcu_read_unlock(); 5816 5817 if (!sid) 5818 return 0; 5819 5820 error = security_sid_to_context(sid, value, &len); 5821 if (error) 5822 return error; 5823 return len; 5824 5825 invalid: 5826 rcu_read_unlock(); 5827 return -EINVAL; 5828 } 5829 5830 static int selinux_setprocattr(struct task_struct *p, 5831 char *name, void *value, size_t size) 5832 { 5833 struct task_security_struct *tsec; 5834 struct cred *new; 5835 u32 sid = 0, ptsid; 5836 int error; 5837 char *str = value; 5838 5839 if (current != p) { 5840 /* SELinux only allows a process to change its own 5841 security attributes. */ 5842 return -EACCES; 5843 } 5844 5845 /* 5846 * Basic control over ability to set these attributes at all. 5847 * current == p, but we'll pass them separately in case the 5848 * above restriction is ever removed. 5849 */ 5850 if (!strcmp(name, "exec")) 5851 error = current_has_perm(p, PROCESS__SETEXEC); 5852 else if (!strcmp(name, "fscreate")) 5853 error = current_has_perm(p, PROCESS__SETFSCREATE); 5854 else if (!strcmp(name, "keycreate")) 5855 error = current_has_perm(p, PROCESS__SETKEYCREATE); 5856 else if (!strcmp(name, "sockcreate")) 5857 error = current_has_perm(p, PROCESS__SETSOCKCREATE); 5858 else if (!strcmp(name, "current")) 5859 error = current_has_perm(p, PROCESS__SETCURRENT); 5860 else 5861 error = -EINVAL; 5862 if (error) 5863 return error; 5864 5865 /* Obtain a SID for the context, if one was specified. */ 5866 if (size && str[1] && str[1] != '\n') { 5867 if (str[size-1] == '\n') { 5868 str[size-1] = 0; 5869 size--; 5870 } 5871 error = security_context_to_sid(value, size, &sid, GFP_KERNEL); 5872 if (error == -EINVAL && !strcmp(name, "fscreate")) { 5873 if (!capable(CAP_MAC_ADMIN)) { 5874 struct audit_buffer *ab; 5875 size_t audit_size; 5876 5877 /* We strip a nul only if it is at the end, otherwise the 5878 * context contains a nul and we should audit that */ 5879 if (str[size - 1] == '\0') 5880 audit_size = size - 1; 5881 else 5882 audit_size = size; 5883 ab = audit_log_start(current->audit_context, GFP_ATOMIC, AUDIT_SELINUX_ERR); 5884 audit_log_format(ab, "op=fscreate invalid_context="); 5885 audit_log_n_untrustedstring(ab, value, audit_size); 5886 audit_log_end(ab); 5887 5888 return error; 5889 } 5890 error = security_context_to_sid_force(value, size, 5891 &sid); 5892 } 5893 if (error) 5894 return error; 5895 } 5896 5897 new = prepare_creds(); 5898 if (!new) 5899 return -ENOMEM; 5900 5901 /* Permission checking based on the specified context is 5902 performed during the actual operation (execve, 5903 open/mkdir/...), when we know the full context of the 5904 operation. See selinux_bprm_set_creds for the execve 5905 checks and may_create for the file creation checks. The 5906 operation will then fail if the context is not permitted. */ 5907 tsec = new->security; 5908 if (!strcmp(name, "exec")) { 5909 tsec->exec_sid = sid; 5910 } else if (!strcmp(name, "fscreate")) { 5911 tsec->create_sid = sid; 5912 } else if (!strcmp(name, "keycreate")) { 5913 error = may_create_key(sid, p); 5914 if (error) 5915 goto abort_change; 5916 tsec->keycreate_sid = sid; 5917 } else if (!strcmp(name, "sockcreate")) { 5918 tsec->sockcreate_sid = sid; 5919 } else if (!strcmp(name, "current")) { 5920 error = -EINVAL; 5921 if (sid == 0) 5922 goto abort_change; 5923 5924 /* Only allow single threaded processes to change context */ 5925 error = -EPERM; 5926 if (!current_is_single_threaded()) { 5927 error = security_bounded_transition(tsec->sid, sid); 5928 if (error) 5929 goto abort_change; 5930 } 5931 5932 /* Check permissions for the transition. */ 5933 error = avc_has_perm(tsec->sid, sid, SECCLASS_PROCESS, 5934 PROCESS__DYNTRANSITION, NULL); 5935 if (error) 5936 goto abort_change; 5937 5938 /* Check for ptracing, and update the task SID if ok. 5939 Otherwise, leave SID unchanged and fail. */ 5940 ptsid = ptrace_parent_sid(p); 5941 if (ptsid != 0) { 5942 error = avc_has_perm(ptsid, sid, SECCLASS_PROCESS, 5943 PROCESS__PTRACE, NULL); 5944 if (error) 5945 goto abort_change; 5946 } 5947 5948 tsec->sid = sid; 5949 } else { 5950 error = -EINVAL; 5951 goto abort_change; 5952 } 5953 5954 commit_creds(new); 5955 return size; 5956 5957 abort_change: 5958 abort_creds(new); 5959 return error; 5960 } 5961 5962 static int selinux_ismaclabel(const char *name) 5963 { 5964 return (strcmp(name, XATTR_SELINUX_SUFFIX) == 0); 5965 } 5966 5967 static int selinux_secid_to_secctx(u32 secid, char **secdata, u32 *seclen) 5968 { 5969 return security_sid_to_context(secid, secdata, seclen); 5970 } 5971 5972 static int selinux_secctx_to_secid(const char *secdata, u32 seclen, u32 *secid) 5973 { 5974 return security_context_to_sid(secdata, seclen, secid, GFP_KERNEL); 5975 } 5976 5977 static void selinux_release_secctx(char *secdata, u32 seclen) 5978 { 5979 kfree(secdata); 5980 } 5981 5982 static void selinux_inode_invalidate_secctx(struct inode *inode) 5983 { 5984 struct inode_security_struct *isec = inode->i_security; 5985 5986 mutex_lock(&isec->lock); 5987 isec->initialized = LABEL_INVALID; 5988 mutex_unlock(&isec->lock); 5989 } 5990 5991 /* 5992 * called with inode->i_mutex locked 5993 */ 5994 static int selinux_inode_notifysecctx(struct inode *inode, void *ctx, u32 ctxlen) 5995 { 5996 return selinux_inode_setsecurity(inode, XATTR_SELINUX_SUFFIX, ctx, ctxlen, 0); 5997 } 5998 5999 /* 6000 * called with inode->i_mutex locked 6001 */ 6002 static int selinux_inode_setsecctx(struct dentry *dentry, void *ctx, u32 ctxlen) 6003 { 6004 return __vfs_setxattr_noperm(dentry, XATTR_NAME_SELINUX, ctx, ctxlen, 0); 6005 } 6006 6007 static int selinux_inode_getsecctx(struct inode *inode, void **ctx, u32 *ctxlen) 6008 { 6009 int len = 0; 6010 len = selinux_inode_getsecurity(inode, XATTR_SELINUX_SUFFIX, 6011 ctx, true); 6012 if (len < 0) 6013 return len; 6014 *ctxlen = len; 6015 return 0; 6016 } 6017 #ifdef CONFIG_KEYS 6018 6019 static int selinux_key_alloc(struct key *k, const struct cred *cred, 6020 unsigned long flags) 6021 { 6022 const struct task_security_struct *tsec; 6023 struct key_security_struct *ksec; 6024 6025 ksec = kzalloc(sizeof(struct key_security_struct), GFP_KERNEL); 6026 if (!ksec) 6027 return -ENOMEM; 6028 6029 tsec = cred->security; 6030 if (tsec->keycreate_sid) 6031 ksec->sid = tsec->keycreate_sid; 6032 else 6033 ksec->sid = tsec->sid; 6034 6035 k->security = ksec; 6036 return 0; 6037 } 6038 6039 static void selinux_key_free(struct key *k) 6040 { 6041 struct key_security_struct *ksec = k->security; 6042 6043 k->security = NULL; 6044 kfree(ksec); 6045 } 6046 6047 static int selinux_key_permission(key_ref_t key_ref, 6048 const struct cred *cred, 6049 unsigned perm) 6050 { 6051 struct key *key; 6052 struct key_security_struct *ksec; 6053 u32 sid; 6054 6055 /* if no specific permissions are requested, we skip the 6056 permission check. No serious, additional covert channels 6057 appear to be created. */ 6058 if (perm == 0) 6059 return 0; 6060 6061 sid = cred_sid(cred); 6062 6063 key = key_ref_to_ptr(key_ref); 6064 ksec = key->security; 6065 6066 return avc_has_perm(sid, ksec->sid, SECCLASS_KEY, perm, NULL); 6067 } 6068 6069 static int selinux_key_getsecurity(struct key *key, char **_buffer) 6070 { 6071 struct key_security_struct *ksec = key->security; 6072 char *context = NULL; 6073 unsigned len; 6074 int rc; 6075 6076 rc = security_sid_to_context(ksec->sid, &context, &len); 6077 if (!rc) 6078 rc = len; 6079 *_buffer = context; 6080 return rc; 6081 } 6082 6083 #endif 6084 6085 static struct security_hook_list selinux_hooks[] = { 6086 LSM_HOOK_INIT(binder_set_context_mgr, selinux_binder_set_context_mgr), 6087 LSM_HOOK_INIT(binder_transaction, selinux_binder_transaction), 6088 LSM_HOOK_INIT(binder_transfer_binder, selinux_binder_transfer_binder), 6089 LSM_HOOK_INIT(binder_transfer_file, selinux_binder_transfer_file), 6090 6091 LSM_HOOK_INIT(ptrace_access_check, selinux_ptrace_access_check), 6092 LSM_HOOK_INIT(ptrace_traceme, selinux_ptrace_traceme), 6093 LSM_HOOK_INIT(capget, selinux_capget), 6094 LSM_HOOK_INIT(capset, selinux_capset), 6095 LSM_HOOK_INIT(capable, selinux_capable), 6096 LSM_HOOK_INIT(quotactl, selinux_quotactl), 6097 LSM_HOOK_INIT(quota_on, selinux_quota_on), 6098 LSM_HOOK_INIT(syslog, selinux_syslog), 6099 LSM_HOOK_INIT(vm_enough_memory, selinux_vm_enough_memory), 6100 6101 LSM_HOOK_INIT(netlink_send, selinux_netlink_send), 6102 6103 LSM_HOOK_INIT(bprm_set_creds, selinux_bprm_set_creds), 6104 LSM_HOOK_INIT(bprm_committing_creds, selinux_bprm_committing_creds), 6105 LSM_HOOK_INIT(bprm_committed_creds, selinux_bprm_committed_creds), 6106 LSM_HOOK_INIT(bprm_secureexec, selinux_bprm_secureexec), 6107 6108 LSM_HOOK_INIT(sb_alloc_security, selinux_sb_alloc_security), 6109 LSM_HOOK_INIT(sb_free_security, selinux_sb_free_security), 6110 LSM_HOOK_INIT(sb_copy_data, selinux_sb_copy_data), 6111 LSM_HOOK_INIT(sb_remount, selinux_sb_remount), 6112 LSM_HOOK_INIT(sb_kern_mount, selinux_sb_kern_mount), 6113 LSM_HOOK_INIT(sb_show_options, selinux_sb_show_options), 6114 LSM_HOOK_INIT(sb_statfs, selinux_sb_statfs), 6115 LSM_HOOK_INIT(sb_mount, selinux_mount), 6116 LSM_HOOK_INIT(sb_umount, selinux_umount), 6117 LSM_HOOK_INIT(sb_set_mnt_opts, selinux_set_mnt_opts), 6118 LSM_HOOK_INIT(sb_clone_mnt_opts, selinux_sb_clone_mnt_opts), 6119 LSM_HOOK_INIT(sb_parse_opts_str, selinux_parse_opts_str), 6120 6121 LSM_HOOK_INIT(dentry_init_security, selinux_dentry_init_security), 6122 LSM_HOOK_INIT(dentry_create_files_as, selinux_dentry_create_files_as), 6123 6124 LSM_HOOK_INIT(inode_alloc_security, selinux_inode_alloc_security), 6125 LSM_HOOK_INIT(inode_free_security, selinux_inode_free_security), 6126 LSM_HOOK_INIT(inode_init_security, selinux_inode_init_security), 6127 LSM_HOOK_INIT(inode_create, selinux_inode_create), 6128 LSM_HOOK_INIT(inode_link, selinux_inode_link), 6129 LSM_HOOK_INIT(inode_unlink, selinux_inode_unlink), 6130 LSM_HOOK_INIT(inode_symlink, selinux_inode_symlink), 6131 LSM_HOOK_INIT(inode_mkdir, selinux_inode_mkdir), 6132 LSM_HOOK_INIT(inode_rmdir, selinux_inode_rmdir), 6133 LSM_HOOK_INIT(inode_mknod, selinux_inode_mknod), 6134 LSM_HOOK_INIT(inode_rename, selinux_inode_rename), 6135 LSM_HOOK_INIT(inode_readlink, selinux_inode_readlink), 6136 LSM_HOOK_INIT(inode_follow_link, selinux_inode_follow_link), 6137 LSM_HOOK_INIT(inode_permission, selinux_inode_permission), 6138 LSM_HOOK_INIT(inode_setattr, selinux_inode_setattr), 6139 LSM_HOOK_INIT(inode_getattr, selinux_inode_getattr), 6140 LSM_HOOK_INIT(inode_setxattr, selinux_inode_setxattr), 6141 LSM_HOOK_INIT(inode_post_setxattr, selinux_inode_post_setxattr), 6142 LSM_HOOK_INIT(inode_getxattr, selinux_inode_getxattr), 6143 LSM_HOOK_INIT(inode_listxattr, selinux_inode_listxattr), 6144 LSM_HOOK_INIT(inode_removexattr, selinux_inode_removexattr), 6145 LSM_HOOK_INIT(inode_getsecurity, selinux_inode_getsecurity), 6146 LSM_HOOK_INIT(inode_setsecurity, selinux_inode_setsecurity), 6147 LSM_HOOK_INIT(inode_listsecurity, selinux_inode_listsecurity), 6148 LSM_HOOK_INIT(inode_getsecid, selinux_inode_getsecid), 6149 LSM_HOOK_INIT(inode_copy_up, selinux_inode_copy_up), 6150 LSM_HOOK_INIT(inode_copy_up_xattr, selinux_inode_copy_up_xattr), 6151 6152 LSM_HOOK_INIT(file_permission, selinux_file_permission), 6153 LSM_HOOK_INIT(file_alloc_security, selinux_file_alloc_security), 6154 LSM_HOOK_INIT(file_free_security, selinux_file_free_security), 6155 LSM_HOOK_INIT(file_ioctl, selinux_file_ioctl), 6156 LSM_HOOK_INIT(mmap_file, selinux_mmap_file), 6157 LSM_HOOK_INIT(mmap_addr, selinux_mmap_addr), 6158 LSM_HOOK_INIT(file_mprotect, selinux_file_mprotect), 6159 LSM_HOOK_INIT(file_lock, selinux_file_lock), 6160 LSM_HOOK_INIT(file_fcntl, selinux_file_fcntl), 6161 LSM_HOOK_INIT(file_set_fowner, selinux_file_set_fowner), 6162 LSM_HOOK_INIT(file_send_sigiotask, selinux_file_send_sigiotask), 6163 LSM_HOOK_INIT(file_receive, selinux_file_receive), 6164 6165 LSM_HOOK_INIT(file_open, selinux_file_open), 6166 6167 LSM_HOOK_INIT(task_create, selinux_task_create), 6168 LSM_HOOK_INIT(cred_alloc_blank, selinux_cred_alloc_blank), 6169 LSM_HOOK_INIT(cred_free, selinux_cred_free), 6170 LSM_HOOK_INIT(cred_prepare, selinux_cred_prepare), 6171 LSM_HOOK_INIT(cred_transfer, selinux_cred_transfer), 6172 LSM_HOOK_INIT(kernel_act_as, selinux_kernel_act_as), 6173 LSM_HOOK_INIT(kernel_create_files_as, selinux_kernel_create_files_as), 6174 LSM_HOOK_INIT(kernel_module_request, selinux_kernel_module_request), 6175 LSM_HOOK_INIT(kernel_read_file, selinux_kernel_read_file), 6176 LSM_HOOK_INIT(task_setpgid, selinux_task_setpgid), 6177 LSM_HOOK_INIT(task_getpgid, selinux_task_getpgid), 6178 LSM_HOOK_INIT(task_getsid, selinux_task_getsid), 6179 LSM_HOOK_INIT(task_getsecid, selinux_task_getsecid), 6180 LSM_HOOK_INIT(task_setnice, selinux_task_setnice), 6181 LSM_HOOK_INIT(task_setioprio, selinux_task_setioprio), 6182 LSM_HOOK_INIT(task_getioprio, selinux_task_getioprio), 6183 LSM_HOOK_INIT(task_setrlimit, selinux_task_setrlimit), 6184 LSM_HOOK_INIT(task_setscheduler, selinux_task_setscheduler), 6185 LSM_HOOK_INIT(task_getscheduler, selinux_task_getscheduler), 6186 LSM_HOOK_INIT(task_movememory, selinux_task_movememory), 6187 LSM_HOOK_INIT(task_kill, selinux_task_kill), 6188 LSM_HOOK_INIT(task_wait, selinux_task_wait), 6189 LSM_HOOK_INIT(task_to_inode, selinux_task_to_inode), 6190 6191 LSM_HOOK_INIT(ipc_permission, selinux_ipc_permission), 6192 LSM_HOOK_INIT(ipc_getsecid, selinux_ipc_getsecid), 6193 6194 LSM_HOOK_INIT(msg_msg_alloc_security, selinux_msg_msg_alloc_security), 6195 LSM_HOOK_INIT(msg_msg_free_security, selinux_msg_msg_free_security), 6196 6197 LSM_HOOK_INIT(msg_queue_alloc_security, 6198 selinux_msg_queue_alloc_security), 6199 LSM_HOOK_INIT(msg_queue_free_security, selinux_msg_queue_free_security), 6200 LSM_HOOK_INIT(msg_queue_associate, selinux_msg_queue_associate), 6201 LSM_HOOK_INIT(msg_queue_msgctl, selinux_msg_queue_msgctl), 6202 LSM_HOOK_INIT(msg_queue_msgsnd, selinux_msg_queue_msgsnd), 6203 LSM_HOOK_INIT(msg_queue_msgrcv, selinux_msg_queue_msgrcv), 6204 6205 LSM_HOOK_INIT(shm_alloc_security, selinux_shm_alloc_security), 6206 LSM_HOOK_INIT(shm_free_security, selinux_shm_free_security), 6207 LSM_HOOK_INIT(shm_associate, selinux_shm_associate), 6208 LSM_HOOK_INIT(shm_shmctl, selinux_shm_shmctl), 6209 LSM_HOOK_INIT(shm_shmat, selinux_shm_shmat), 6210 6211 LSM_HOOK_INIT(sem_alloc_security, selinux_sem_alloc_security), 6212 LSM_HOOK_INIT(sem_free_security, selinux_sem_free_security), 6213 LSM_HOOK_INIT(sem_associate, selinux_sem_associate), 6214 LSM_HOOK_INIT(sem_semctl, selinux_sem_semctl), 6215 LSM_HOOK_INIT(sem_semop, selinux_sem_semop), 6216 6217 LSM_HOOK_INIT(d_instantiate, selinux_d_instantiate), 6218 6219 LSM_HOOK_INIT(getprocattr, selinux_getprocattr), 6220 LSM_HOOK_INIT(setprocattr, selinux_setprocattr), 6221 6222 LSM_HOOK_INIT(ismaclabel, selinux_ismaclabel), 6223 LSM_HOOK_INIT(secid_to_secctx, selinux_secid_to_secctx), 6224 LSM_HOOK_INIT(secctx_to_secid, selinux_secctx_to_secid), 6225 LSM_HOOK_INIT(release_secctx, selinux_release_secctx), 6226 LSM_HOOK_INIT(inode_invalidate_secctx, selinux_inode_invalidate_secctx), 6227 LSM_HOOK_INIT(inode_notifysecctx, selinux_inode_notifysecctx), 6228 LSM_HOOK_INIT(inode_setsecctx, selinux_inode_setsecctx), 6229 LSM_HOOK_INIT(inode_getsecctx, selinux_inode_getsecctx), 6230 6231 LSM_HOOK_INIT(unix_stream_connect, selinux_socket_unix_stream_connect), 6232 LSM_HOOK_INIT(unix_may_send, selinux_socket_unix_may_send), 6233 6234 LSM_HOOK_INIT(socket_create, selinux_socket_create), 6235 LSM_HOOK_INIT(socket_post_create, selinux_socket_post_create), 6236 LSM_HOOK_INIT(socket_bind, selinux_socket_bind), 6237 LSM_HOOK_INIT(socket_connect, selinux_socket_connect), 6238 LSM_HOOK_INIT(socket_listen, selinux_socket_listen), 6239 LSM_HOOK_INIT(socket_accept, selinux_socket_accept), 6240 LSM_HOOK_INIT(socket_sendmsg, selinux_socket_sendmsg), 6241 LSM_HOOK_INIT(socket_recvmsg, selinux_socket_recvmsg), 6242 LSM_HOOK_INIT(socket_getsockname, selinux_socket_getsockname), 6243 LSM_HOOK_INIT(socket_getpeername, selinux_socket_getpeername), 6244 LSM_HOOK_INIT(socket_getsockopt, selinux_socket_getsockopt), 6245 LSM_HOOK_INIT(socket_setsockopt, selinux_socket_setsockopt), 6246 LSM_HOOK_INIT(socket_shutdown, selinux_socket_shutdown), 6247 LSM_HOOK_INIT(socket_sock_rcv_skb, selinux_socket_sock_rcv_skb), 6248 LSM_HOOK_INIT(socket_getpeersec_stream, 6249 selinux_socket_getpeersec_stream), 6250 LSM_HOOK_INIT(socket_getpeersec_dgram, selinux_socket_getpeersec_dgram), 6251 LSM_HOOK_INIT(sk_alloc_security, selinux_sk_alloc_security), 6252 LSM_HOOK_INIT(sk_free_security, selinux_sk_free_security), 6253 LSM_HOOK_INIT(sk_clone_security, selinux_sk_clone_security), 6254 LSM_HOOK_INIT(sk_getsecid, selinux_sk_getsecid), 6255 LSM_HOOK_INIT(sock_graft, selinux_sock_graft), 6256 LSM_HOOK_INIT(inet_conn_request, selinux_inet_conn_request), 6257 LSM_HOOK_INIT(inet_csk_clone, selinux_inet_csk_clone), 6258 LSM_HOOK_INIT(inet_conn_established, selinux_inet_conn_established), 6259 LSM_HOOK_INIT(secmark_relabel_packet, selinux_secmark_relabel_packet), 6260 LSM_HOOK_INIT(secmark_refcount_inc, selinux_secmark_refcount_inc), 6261 LSM_HOOK_INIT(secmark_refcount_dec, selinux_secmark_refcount_dec), 6262 LSM_HOOK_INIT(req_classify_flow, selinux_req_classify_flow), 6263 LSM_HOOK_INIT(tun_dev_alloc_security, selinux_tun_dev_alloc_security), 6264 LSM_HOOK_INIT(tun_dev_free_security, selinux_tun_dev_free_security), 6265 LSM_HOOK_INIT(tun_dev_create, selinux_tun_dev_create), 6266 LSM_HOOK_INIT(tun_dev_attach_queue, selinux_tun_dev_attach_queue), 6267 LSM_HOOK_INIT(tun_dev_attach, selinux_tun_dev_attach), 6268 LSM_HOOK_INIT(tun_dev_open, selinux_tun_dev_open), 6269 6270 #ifdef CONFIG_SECURITY_NETWORK_XFRM 6271 LSM_HOOK_INIT(xfrm_policy_alloc_security, selinux_xfrm_policy_alloc), 6272 LSM_HOOK_INIT(xfrm_policy_clone_security, selinux_xfrm_policy_clone), 6273 LSM_HOOK_INIT(xfrm_policy_free_security, selinux_xfrm_policy_free), 6274 LSM_HOOK_INIT(xfrm_policy_delete_security, selinux_xfrm_policy_delete), 6275 LSM_HOOK_INIT(xfrm_state_alloc, selinux_xfrm_state_alloc), 6276 LSM_HOOK_INIT(xfrm_state_alloc_acquire, 6277 selinux_xfrm_state_alloc_acquire), 6278 LSM_HOOK_INIT(xfrm_state_free_security, selinux_xfrm_state_free), 6279 LSM_HOOK_INIT(xfrm_state_delete_security, selinux_xfrm_state_delete), 6280 LSM_HOOK_INIT(xfrm_policy_lookup, selinux_xfrm_policy_lookup), 6281 LSM_HOOK_INIT(xfrm_state_pol_flow_match, 6282 selinux_xfrm_state_pol_flow_match), 6283 LSM_HOOK_INIT(xfrm_decode_session, selinux_xfrm_decode_session), 6284 #endif 6285 6286 #ifdef CONFIG_KEYS 6287 LSM_HOOK_INIT(key_alloc, selinux_key_alloc), 6288 LSM_HOOK_INIT(key_free, selinux_key_free), 6289 LSM_HOOK_INIT(key_permission, selinux_key_permission), 6290 LSM_HOOK_INIT(key_getsecurity, selinux_key_getsecurity), 6291 #endif 6292 6293 #ifdef CONFIG_AUDIT 6294 LSM_HOOK_INIT(audit_rule_init, selinux_audit_rule_init), 6295 LSM_HOOK_INIT(audit_rule_known, selinux_audit_rule_known), 6296 LSM_HOOK_INIT(audit_rule_match, selinux_audit_rule_match), 6297 LSM_HOOK_INIT(audit_rule_free, selinux_audit_rule_free), 6298 #endif 6299 }; 6300 6301 static __init int selinux_init(void) 6302 { 6303 if (!security_module_enable("selinux")) { 6304 selinux_enabled = 0; 6305 return 0; 6306 } 6307 6308 if (!selinux_enabled) { 6309 printk(KERN_INFO "SELinux: Disabled at boot.\n"); 6310 return 0; 6311 } 6312 6313 printk(KERN_INFO "SELinux: Initializing.\n"); 6314 6315 /* Set the security state for the initial task. */ 6316 cred_init_security(); 6317 6318 default_noexec = !(VM_DATA_DEFAULT_FLAGS & VM_EXEC); 6319 6320 sel_inode_cache = kmem_cache_create("selinux_inode_security", 6321 sizeof(struct inode_security_struct), 6322 0, SLAB_PANIC, NULL); 6323 file_security_cache = kmem_cache_create("selinux_file_security", 6324 sizeof(struct file_security_struct), 6325 0, SLAB_PANIC, NULL); 6326 avc_init(); 6327 6328 security_add_hooks(selinux_hooks, ARRAY_SIZE(selinux_hooks)); 6329 6330 if (avc_add_callback(selinux_netcache_avc_callback, AVC_CALLBACK_RESET)) 6331 panic("SELinux: Unable to register AVC netcache callback\n"); 6332 6333 if (selinux_enforcing) 6334 printk(KERN_DEBUG "SELinux: Starting in enforcing mode\n"); 6335 else 6336 printk(KERN_DEBUG "SELinux: Starting in permissive mode\n"); 6337 6338 return 0; 6339 } 6340 6341 static void delayed_superblock_init(struct super_block *sb, void *unused) 6342 { 6343 superblock_doinit(sb, NULL); 6344 } 6345 6346 void selinux_complete_init(void) 6347 { 6348 printk(KERN_DEBUG "SELinux: Completing initialization.\n"); 6349 6350 /* Set up any superblocks initialized prior to the policy load. */ 6351 printk(KERN_DEBUG "SELinux: Setting up existing superblocks.\n"); 6352 iterate_supers(delayed_superblock_init, NULL); 6353 } 6354 6355 /* SELinux requires early initialization in order to label 6356 all processes and objects when they are created. */ 6357 security_initcall(selinux_init); 6358 6359 #if defined(CONFIG_NETFILTER) 6360 6361 static struct nf_hook_ops selinux_nf_ops[] = { 6362 { 6363 .hook = selinux_ipv4_postroute, 6364 .pf = NFPROTO_IPV4, 6365 .hooknum = NF_INET_POST_ROUTING, 6366 .priority = NF_IP_PRI_SELINUX_LAST, 6367 }, 6368 { 6369 .hook = selinux_ipv4_forward, 6370 .pf = NFPROTO_IPV4, 6371 .hooknum = NF_INET_FORWARD, 6372 .priority = NF_IP_PRI_SELINUX_FIRST, 6373 }, 6374 { 6375 .hook = selinux_ipv4_output, 6376 .pf = NFPROTO_IPV4, 6377 .hooknum = NF_INET_LOCAL_OUT, 6378 .priority = NF_IP_PRI_SELINUX_FIRST, 6379 }, 6380 #if IS_ENABLED(CONFIG_IPV6) 6381 { 6382 .hook = selinux_ipv6_postroute, 6383 .pf = NFPROTO_IPV6, 6384 .hooknum = NF_INET_POST_ROUTING, 6385 .priority = NF_IP6_PRI_SELINUX_LAST, 6386 }, 6387 { 6388 .hook = selinux_ipv6_forward, 6389 .pf = NFPROTO_IPV6, 6390 .hooknum = NF_INET_FORWARD, 6391 .priority = NF_IP6_PRI_SELINUX_FIRST, 6392 }, 6393 { 6394 .hook = selinux_ipv6_output, 6395 .pf = NFPROTO_IPV6, 6396 .hooknum = NF_INET_LOCAL_OUT, 6397 .priority = NF_IP6_PRI_SELINUX_FIRST, 6398 }, 6399 #endif /* IPV6 */ 6400 }; 6401 6402 static int __init selinux_nf_ip_init(void) 6403 { 6404 int err; 6405 6406 if (!selinux_enabled) 6407 return 0; 6408 6409 printk(KERN_DEBUG "SELinux: Registering netfilter hooks\n"); 6410 6411 err = nf_register_hooks(selinux_nf_ops, ARRAY_SIZE(selinux_nf_ops)); 6412 if (err) 6413 panic("SELinux: nf_register_hooks: error %d\n", err); 6414 6415 return 0; 6416 } 6417 6418 __initcall(selinux_nf_ip_init); 6419 6420 #ifdef CONFIG_SECURITY_SELINUX_DISABLE 6421 static void selinux_nf_ip_exit(void) 6422 { 6423 printk(KERN_DEBUG "SELinux: Unregistering netfilter hooks\n"); 6424 6425 nf_unregister_hooks(selinux_nf_ops, ARRAY_SIZE(selinux_nf_ops)); 6426 } 6427 #endif 6428 6429 #else /* CONFIG_NETFILTER */ 6430 6431 #ifdef CONFIG_SECURITY_SELINUX_DISABLE 6432 #define selinux_nf_ip_exit() 6433 #endif 6434 6435 #endif /* CONFIG_NETFILTER */ 6436 6437 #ifdef CONFIG_SECURITY_SELINUX_DISABLE 6438 static int selinux_disabled; 6439 6440 int selinux_disable(void) 6441 { 6442 if (ss_initialized) { 6443 /* Not permitted after initial policy load. */ 6444 return -EINVAL; 6445 } 6446 6447 if (selinux_disabled) { 6448 /* Only do this once. */ 6449 return -EINVAL; 6450 } 6451 6452 printk(KERN_INFO "SELinux: Disabled at runtime.\n"); 6453 6454 selinux_disabled = 1; 6455 selinux_enabled = 0; 6456 6457 security_delete_hooks(selinux_hooks, ARRAY_SIZE(selinux_hooks)); 6458 6459 /* Try to destroy the avc node cache */ 6460 avc_disable(); 6461 6462 /* Unregister netfilter hooks. */ 6463 selinux_nf_ip_exit(); 6464 6465 /* Unregister selinuxfs. */ 6466 exit_sel_fs(); 6467 6468 return 0; 6469 } 6470 #endif 6471