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 spin_lock_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 isec->initialized = LABEL_INVALID; 241 inode->i_security = isec; 242 243 return 0; 244 } 245 246 static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dentry); 247 248 /* 249 * Try reloading inode security labels that have been marked as invalid. The 250 * @may_sleep parameter indicates when sleeping and thus reloading labels is 251 * allowed; when set to false, returns -ECHILD when the label is 252 * invalid. The @opt_dentry parameter should be set to a dentry of the inode; 253 * when no dentry is available, set it to NULL instead. 254 */ 255 static int __inode_security_revalidate(struct inode *inode, 256 struct dentry *opt_dentry, 257 bool may_sleep) 258 { 259 struct inode_security_struct *isec = inode->i_security; 260 261 might_sleep_if(may_sleep); 262 263 if (ss_initialized && isec->initialized != LABEL_INITIALIZED) { 264 if (!may_sleep) 265 return -ECHILD; 266 267 /* 268 * Try reloading the inode security label. This will fail if 269 * @opt_dentry is NULL and no dentry for this inode can be 270 * found; in that case, continue using the old label. 271 */ 272 inode_doinit_with_dentry(inode, opt_dentry); 273 } 274 return 0; 275 } 276 277 static struct inode_security_struct *inode_security_novalidate(struct inode *inode) 278 { 279 return inode->i_security; 280 } 281 282 static struct inode_security_struct *inode_security_rcu(struct inode *inode, bool rcu) 283 { 284 int error; 285 286 error = __inode_security_revalidate(inode, NULL, !rcu); 287 if (error) 288 return ERR_PTR(error); 289 return inode->i_security; 290 } 291 292 /* 293 * Get the security label of an inode. 294 */ 295 static struct inode_security_struct *inode_security(struct inode *inode) 296 { 297 __inode_security_revalidate(inode, NULL, true); 298 return inode->i_security; 299 } 300 301 static struct inode_security_struct *backing_inode_security_novalidate(struct dentry *dentry) 302 { 303 struct inode *inode = d_backing_inode(dentry); 304 305 return inode->i_security; 306 } 307 308 /* 309 * Get the security label of a dentry's backing inode. 310 */ 311 static struct inode_security_struct *backing_inode_security(struct dentry *dentry) 312 { 313 struct inode *inode = d_backing_inode(dentry); 314 315 __inode_security_revalidate(inode, dentry, true); 316 return inode->i_security; 317 } 318 319 static void inode_free_rcu(struct rcu_head *head) 320 { 321 struct inode_security_struct *isec; 322 323 isec = container_of(head, struct inode_security_struct, rcu); 324 kmem_cache_free(sel_inode_cache, isec); 325 } 326 327 static void inode_free_security(struct inode *inode) 328 { 329 struct inode_security_struct *isec = inode->i_security; 330 struct superblock_security_struct *sbsec = inode->i_sb->s_security; 331 332 /* 333 * As not all inode security structures are in a list, we check for 334 * empty list outside of the lock to make sure that we won't waste 335 * time taking a lock doing nothing. 336 * 337 * The list_del_init() function can be safely called more than once. 338 * It should not be possible for this function to be called with 339 * concurrent list_add(), but for better safety against future changes 340 * in the code, we use list_empty_careful() here. 341 */ 342 if (!list_empty_careful(&isec->list)) { 343 spin_lock(&sbsec->isec_lock); 344 list_del_init(&isec->list); 345 spin_unlock(&sbsec->isec_lock); 346 } 347 348 /* 349 * The inode may still be referenced in a path walk and 350 * a call to selinux_inode_permission() can be made 351 * after inode_free_security() is called. Ideally, the VFS 352 * wouldn't do this, but fixing that is a much harder 353 * job. For now, simply free the i_security via RCU, and 354 * leave the current inode->i_security pointer intact. 355 * The inode will be freed after the RCU grace period too. 356 */ 357 call_rcu(&isec->rcu, inode_free_rcu); 358 } 359 360 static int file_alloc_security(struct file *file) 361 { 362 struct file_security_struct *fsec; 363 u32 sid = current_sid(); 364 365 fsec = kmem_cache_zalloc(file_security_cache, GFP_KERNEL); 366 if (!fsec) 367 return -ENOMEM; 368 369 fsec->sid = sid; 370 fsec->fown_sid = sid; 371 file->f_security = fsec; 372 373 return 0; 374 } 375 376 static void file_free_security(struct file *file) 377 { 378 struct file_security_struct *fsec = file->f_security; 379 file->f_security = NULL; 380 kmem_cache_free(file_security_cache, fsec); 381 } 382 383 static int superblock_alloc_security(struct super_block *sb) 384 { 385 struct superblock_security_struct *sbsec; 386 387 sbsec = kzalloc(sizeof(struct superblock_security_struct), GFP_KERNEL); 388 if (!sbsec) 389 return -ENOMEM; 390 391 mutex_init(&sbsec->lock); 392 INIT_LIST_HEAD(&sbsec->isec_head); 393 spin_lock_init(&sbsec->isec_lock); 394 sbsec->sb = sb; 395 sbsec->sid = SECINITSID_UNLABELED; 396 sbsec->def_sid = SECINITSID_FILE; 397 sbsec->mntpoint_sid = SECINITSID_UNLABELED; 398 sb->s_security = sbsec; 399 400 return 0; 401 } 402 403 static void superblock_free_security(struct super_block *sb) 404 { 405 struct superblock_security_struct *sbsec = sb->s_security; 406 sb->s_security = NULL; 407 kfree(sbsec); 408 } 409 410 /* The file system's label must be initialized prior to use. */ 411 412 static const char *labeling_behaviors[7] = { 413 "uses xattr", 414 "uses transition SIDs", 415 "uses task SIDs", 416 "uses genfs_contexts", 417 "not configured for labeling", 418 "uses mountpoint labeling", 419 "uses native labeling", 420 }; 421 422 static inline int inode_doinit(struct inode *inode) 423 { 424 return inode_doinit_with_dentry(inode, NULL); 425 } 426 427 enum { 428 Opt_error = -1, 429 Opt_context = 1, 430 Opt_fscontext = 2, 431 Opt_defcontext = 3, 432 Opt_rootcontext = 4, 433 Opt_labelsupport = 5, 434 Opt_nextmntopt = 6, 435 }; 436 437 #define NUM_SEL_MNT_OPTS (Opt_nextmntopt - 1) 438 439 static const match_table_t tokens = { 440 {Opt_context, CONTEXT_STR "%s"}, 441 {Opt_fscontext, FSCONTEXT_STR "%s"}, 442 {Opt_defcontext, DEFCONTEXT_STR "%s"}, 443 {Opt_rootcontext, ROOTCONTEXT_STR "%s"}, 444 {Opt_labelsupport, LABELSUPP_STR}, 445 {Opt_error, NULL}, 446 }; 447 448 #define SEL_MOUNT_FAIL_MSG "SELinux: duplicate or incompatible mount options\n" 449 450 static int may_context_mount_sb_relabel(u32 sid, 451 struct superblock_security_struct *sbsec, 452 const struct cred *cred) 453 { 454 const struct task_security_struct *tsec = cred->security; 455 int rc; 456 457 rc = avc_has_perm(tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM, 458 FILESYSTEM__RELABELFROM, NULL); 459 if (rc) 460 return rc; 461 462 rc = avc_has_perm(tsec->sid, sid, SECCLASS_FILESYSTEM, 463 FILESYSTEM__RELABELTO, NULL); 464 return rc; 465 } 466 467 static int may_context_mount_inode_relabel(u32 sid, 468 struct superblock_security_struct *sbsec, 469 const struct cred *cred) 470 { 471 const struct task_security_struct *tsec = cred->security; 472 int rc; 473 rc = avc_has_perm(tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM, 474 FILESYSTEM__RELABELFROM, NULL); 475 if (rc) 476 return rc; 477 478 rc = avc_has_perm(sid, sbsec->sid, SECCLASS_FILESYSTEM, 479 FILESYSTEM__ASSOCIATE, NULL); 480 return rc; 481 } 482 483 static int selinux_is_sblabel_mnt(struct super_block *sb) 484 { 485 struct superblock_security_struct *sbsec = sb->s_security; 486 487 return sbsec->behavior == SECURITY_FS_USE_XATTR || 488 sbsec->behavior == SECURITY_FS_USE_TRANS || 489 sbsec->behavior == SECURITY_FS_USE_TASK || 490 sbsec->behavior == SECURITY_FS_USE_NATIVE || 491 /* Special handling. Genfs but also in-core setxattr handler */ 492 !strcmp(sb->s_type->name, "sysfs") || 493 !strcmp(sb->s_type->name, "pstore") || 494 !strcmp(sb->s_type->name, "debugfs") || 495 !strcmp(sb->s_type->name, "rootfs"); 496 } 497 498 static int sb_finish_set_opts(struct super_block *sb) 499 { 500 struct superblock_security_struct *sbsec = sb->s_security; 501 struct dentry *root = sb->s_root; 502 struct inode *root_inode = d_backing_inode(root); 503 int rc = 0; 504 505 if (sbsec->behavior == SECURITY_FS_USE_XATTR) { 506 /* Make sure that the xattr handler exists and that no 507 error other than -ENODATA is returned by getxattr on 508 the root directory. -ENODATA is ok, as this may be 509 the first boot of the SELinux kernel before we have 510 assigned xattr values to the filesystem. */ 511 if (!(root_inode->i_opflags & IOP_XATTR)) { 512 printk(KERN_WARNING "SELinux: (dev %s, type %s) has no " 513 "xattr support\n", sb->s_id, sb->s_type->name); 514 rc = -EOPNOTSUPP; 515 goto out; 516 } 517 518 rc = __vfs_getxattr(root, root_inode, XATTR_NAME_SELINUX, NULL, 0); 519 if (rc < 0 && rc != -ENODATA) { 520 if (rc == -EOPNOTSUPP) 521 printk(KERN_WARNING "SELinux: (dev %s, type " 522 "%s) has no security xattr handler\n", 523 sb->s_id, sb->s_type->name); 524 else 525 printk(KERN_WARNING "SELinux: (dev %s, type " 526 "%s) getxattr errno %d\n", sb->s_id, 527 sb->s_type->name, -rc); 528 goto out; 529 } 530 } 531 532 if (sbsec->behavior > ARRAY_SIZE(labeling_behaviors)) 533 printk(KERN_ERR "SELinux: initialized (dev %s, type %s), unknown behavior\n", 534 sb->s_id, sb->s_type->name); 535 536 sbsec->flags |= SE_SBINITIALIZED; 537 if (selinux_is_sblabel_mnt(sb)) 538 sbsec->flags |= SBLABEL_MNT; 539 540 /* Initialize the root inode. */ 541 rc = inode_doinit_with_dentry(root_inode, root); 542 543 /* Initialize any other inodes associated with the superblock, e.g. 544 inodes created prior to initial policy load or inodes created 545 during get_sb by a pseudo filesystem that directly 546 populates itself. */ 547 spin_lock(&sbsec->isec_lock); 548 next_inode: 549 if (!list_empty(&sbsec->isec_head)) { 550 struct inode_security_struct *isec = 551 list_entry(sbsec->isec_head.next, 552 struct inode_security_struct, list); 553 struct inode *inode = isec->inode; 554 list_del_init(&isec->list); 555 spin_unlock(&sbsec->isec_lock); 556 inode = igrab(inode); 557 if (inode) { 558 if (!IS_PRIVATE(inode)) 559 inode_doinit(inode); 560 iput(inode); 561 } 562 spin_lock(&sbsec->isec_lock); 563 goto next_inode; 564 } 565 spin_unlock(&sbsec->isec_lock); 566 out: 567 return rc; 568 } 569 570 /* 571 * This function should allow an FS to ask what it's mount security 572 * options were so it can use those later for submounts, displaying 573 * mount options, or whatever. 574 */ 575 static int selinux_get_mnt_opts(const struct super_block *sb, 576 struct security_mnt_opts *opts) 577 { 578 int rc = 0, i; 579 struct superblock_security_struct *sbsec = sb->s_security; 580 char *context = NULL; 581 u32 len; 582 char tmp; 583 584 security_init_mnt_opts(opts); 585 586 if (!(sbsec->flags & SE_SBINITIALIZED)) 587 return -EINVAL; 588 589 if (!ss_initialized) 590 return -EINVAL; 591 592 /* make sure we always check enough bits to cover the mask */ 593 BUILD_BUG_ON(SE_MNTMASK >= (1 << NUM_SEL_MNT_OPTS)); 594 595 tmp = sbsec->flags & SE_MNTMASK; 596 /* count the number of mount options for this sb */ 597 for (i = 0; i < NUM_SEL_MNT_OPTS; i++) { 598 if (tmp & 0x01) 599 opts->num_mnt_opts++; 600 tmp >>= 1; 601 } 602 /* Check if the Label support flag is set */ 603 if (sbsec->flags & SBLABEL_MNT) 604 opts->num_mnt_opts++; 605 606 opts->mnt_opts = kcalloc(opts->num_mnt_opts, sizeof(char *), GFP_ATOMIC); 607 if (!opts->mnt_opts) { 608 rc = -ENOMEM; 609 goto out_free; 610 } 611 612 opts->mnt_opts_flags = kcalloc(opts->num_mnt_opts, sizeof(int), GFP_ATOMIC); 613 if (!opts->mnt_opts_flags) { 614 rc = -ENOMEM; 615 goto out_free; 616 } 617 618 i = 0; 619 if (sbsec->flags & FSCONTEXT_MNT) { 620 rc = security_sid_to_context(sbsec->sid, &context, &len); 621 if (rc) 622 goto out_free; 623 opts->mnt_opts[i] = context; 624 opts->mnt_opts_flags[i++] = FSCONTEXT_MNT; 625 } 626 if (sbsec->flags & CONTEXT_MNT) { 627 rc = security_sid_to_context(sbsec->mntpoint_sid, &context, &len); 628 if (rc) 629 goto out_free; 630 opts->mnt_opts[i] = context; 631 opts->mnt_opts_flags[i++] = CONTEXT_MNT; 632 } 633 if (sbsec->flags & DEFCONTEXT_MNT) { 634 rc = security_sid_to_context(sbsec->def_sid, &context, &len); 635 if (rc) 636 goto out_free; 637 opts->mnt_opts[i] = context; 638 opts->mnt_opts_flags[i++] = DEFCONTEXT_MNT; 639 } 640 if (sbsec->flags & ROOTCONTEXT_MNT) { 641 struct dentry *root = sbsec->sb->s_root; 642 struct inode_security_struct *isec = backing_inode_security(root); 643 644 rc = security_sid_to_context(isec->sid, &context, &len); 645 if (rc) 646 goto out_free; 647 opts->mnt_opts[i] = context; 648 opts->mnt_opts_flags[i++] = ROOTCONTEXT_MNT; 649 } 650 if (sbsec->flags & SBLABEL_MNT) { 651 opts->mnt_opts[i] = NULL; 652 opts->mnt_opts_flags[i++] = SBLABEL_MNT; 653 } 654 655 BUG_ON(i != opts->num_mnt_opts); 656 657 return 0; 658 659 out_free: 660 security_free_mnt_opts(opts); 661 return rc; 662 } 663 664 static int bad_option(struct superblock_security_struct *sbsec, char flag, 665 u32 old_sid, u32 new_sid) 666 { 667 char mnt_flags = sbsec->flags & SE_MNTMASK; 668 669 /* check if the old mount command had the same options */ 670 if (sbsec->flags & SE_SBINITIALIZED) 671 if (!(sbsec->flags & flag) || 672 (old_sid != new_sid)) 673 return 1; 674 675 /* check if we were passed the same options twice, 676 * aka someone passed context=a,context=b 677 */ 678 if (!(sbsec->flags & SE_SBINITIALIZED)) 679 if (mnt_flags & flag) 680 return 1; 681 return 0; 682 } 683 684 /* 685 * Allow filesystems with binary mount data to explicitly set mount point 686 * labeling information. 687 */ 688 static int selinux_set_mnt_opts(struct super_block *sb, 689 struct security_mnt_opts *opts, 690 unsigned long kern_flags, 691 unsigned long *set_kern_flags) 692 { 693 const struct cred *cred = current_cred(); 694 int rc = 0, i; 695 struct superblock_security_struct *sbsec = sb->s_security; 696 const char *name = sb->s_type->name; 697 struct dentry *root = sbsec->sb->s_root; 698 struct inode_security_struct *root_isec; 699 u32 fscontext_sid = 0, context_sid = 0, rootcontext_sid = 0; 700 u32 defcontext_sid = 0; 701 char **mount_options = opts->mnt_opts; 702 int *flags = opts->mnt_opts_flags; 703 int num_opts = opts->num_mnt_opts; 704 705 mutex_lock(&sbsec->lock); 706 707 if (!ss_initialized) { 708 if (!num_opts) { 709 /* Defer initialization until selinux_complete_init, 710 after the initial policy is loaded and the security 711 server is ready to handle calls. */ 712 goto out; 713 } 714 rc = -EINVAL; 715 printk(KERN_WARNING "SELinux: Unable to set superblock options " 716 "before the security server is initialized\n"); 717 goto out; 718 } 719 if (kern_flags && !set_kern_flags) { 720 /* Specifying internal flags without providing a place to 721 * place the results is not allowed */ 722 rc = -EINVAL; 723 goto out; 724 } 725 726 /* 727 * Binary mount data FS will come through this function twice. Once 728 * from an explicit call and once from the generic calls from the vfs. 729 * Since the generic VFS calls will not contain any security mount data 730 * we need to skip the double mount verification. 731 * 732 * This does open a hole in which we will not notice if the first 733 * mount using this sb set explict options and a second mount using 734 * this sb does not set any security options. (The first options 735 * will be used for both mounts) 736 */ 737 if ((sbsec->flags & SE_SBINITIALIZED) && (sb->s_type->fs_flags & FS_BINARY_MOUNTDATA) 738 && (num_opts == 0)) 739 goto out; 740 741 root_isec = backing_inode_security_novalidate(root); 742 743 /* 744 * parse the mount options, check if they are valid sids. 745 * also check if someone is trying to mount the same sb more 746 * than once with different security options. 747 */ 748 for (i = 0; i < num_opts; i++) { 749 u32 sid; 750 751 if (flags[i] == SBLABEL_MNT) 752 continue; 753 rc = security_context_str_to_sid(mount_options[i], &sid, GFP_KERNEL); 754 if (rc) { 755 printk(KERN_WARNING "SELinux: security_context_str_to_sid" 756 "(%s) failed for (dev %s, type %s) errno=%d\n", 757 mount_options[i], sb->s_id, name, rc); 758 goto out; 759 } 760 switch (flags[i]) { 761 case FSCONTEXT_MNT: 762 fscontext_sid = sid; 763 764 if (bad_option(sbsec, FSCONTEXT_MNT, sbsec->sid, 765 fscontext_sid)) 766 goto out_double_mount; 767 768 sbsec->flags |= FSCONTEXT_MNT; 769 break; 770 case CONTEXT_MNT: 771 context_sid = sid; 772 773 if (bad_option(sbsec, CONTEXT_MNT, sbsec->mntpoint_sid, 774 context_sid)) 775 goto out_double_mount; 776 777 sbsec->flags |= CONTEXT_MNT; 778 break; 779 case ROOTCONTEXT_MNT: 780 rootcontext_sid = sid; 781 782 if (bad_option(sbsec, ROOTCONTEXT_MNT, root_isec->sid, 783 rootcontext_sid)) 784 goto out_double_mount; 785 786 sbsec->flags |= ROOTCONTEXT_MNT; 787 788 break; 789 case DEFCONTEXT_MNT: 790 defcontext_sid = sid; 791 792 if (bad_option(sbsec, DEFCONTEXT_MNT, sbsec->def_sid, 793 defcontext_sid)) 794 goto out_double_mount; 795 796 sbsec->flags |= DEFCONTEXT_MNT; 797 798 break; 799 default: 800 rc = -EINVAL; 801 goto out; 802 } 803 } 804 805 if (sbsec->flags & SE_SBINITIALIZED) { 806 /* previously mounted with options, but not on this attempt? */ 807 if ((sbsec->flags & SE_MNTMASK) && !num_opts) 808 goto out_double_mount; 809 rc = 0; 810 goto out; 811 } 812 813 if (strcmp(sb->s_type->name, "proc") == 0) 814 sbsec->flags |= SE_SBPROC | SE_SBGENFS; 815 816 if (!strcmp(sb->s_type->name, "debugfs") || 817 !strcmp(sb->s_type->name, "sysfs") || 818 !strcmp(sb->s_type->name, "pstore")) 819 sbsec->flags |= SE_SBGENFS; 820 821 if (!sbsec->behavior) { 822 /* 823 * Determine the labeling behavior to use for this 824 * filesystem type. 825 */ 826 rc = security_fs_use(sb); 827 if (rc) { 828 printk(KERN_WARNING 829 "%s: security_fs_use(%s) returned %d\n", 830 __func__, sb->s_type->name, rc); 831 goto out; 832 } 833 } 834 835 /* 836 * If this is a user namespace mount, no contexts are allowed 837 * on the command line and security labels must be ignored. 838 */ 839 if (sb->s_user_ns != &init_user_ns) { 840 if (context_sid || fscontext_sid || rootcontext_sid || 841 defcontext_sid) { 842 rc = -EACCES; 843 goto out; 844 } 845 if (sbsec->behavior == SECURITY_FS_USE_XATTR) { 846 sbsec->behavior = SECURITY_FS_USE_MNTPOINT; 847 rc = security_transition_sid(current_sid(), current_sid(), 848 SECCLASS_FILE, NULL, 849 &sbsec->mntpoint_sid); 850 if (rc) 851 goto out; 852 } 853 goto out_set_opts; 854 } 855 856 /* sets the context of the superblock for the fs being mounted. */ 857 if (fscontext_sid) { 858 rc = may_context_mount_sb_relabel(fscontext_sid, sbsec, cred); 859 if (rc) 860 goto out; 861 862 sbsec->sid = fscontext_sid; 863 } 864 865 /* 866 * Switch to using mount point labeling behavior. 867 * sets the label used on all file below the mountpoint, and will set 868 * the superblock context if not already set. 869 */ 870 if (kern_flags & SECURITY_LSM_NATIVE_LABELS && !context_sid) { 871 sbsec->behavior = SECURITY_FS_USE_NATIVE; 872 *set_kern_flags |= SECURITY_LSM_NATIVE_LABELS; 873 } 874 875 if (context_sid) { 876 if (!fscontext_sid) { 877 rc = may_context_mount_sb_relabel(context_sid, sbsec, 878 cred); 879 if (rc) 880 goto out; 881 sbsec->sid = context_sid; 882 } else { 883 rc = may_context_mount_inode_relabel(context_sid, sbsec, 884 cred); 885 if (rc) 886 goto out; 887 } 888 if (!rootcontext_sid) 889 rootcontext_sid = context_sid; 890 891 sbsec->mntpoint_sid = context_sid; 892 sbsec->behavior = SECURITY_FS_USE_MNTPOINT; 893 } 894 895 if (rootcontext_sid) { 896 rc = may_context_mount_inode_relabel(rootcontext_sid, sbsec, 897 cred); 898 if (rc) 899 goto out; 900 901 root_isec->sid = rootcontext_sid; 902 root_isec->initialized = LABEL_INITIALIZED; 903 } 904 905 if (defcontext_sid) { 906 if (sbsec->behavior != SECURITY_FS_USE_XATTR && 907 sbsec->behavior != SECURITY_FS_USE_NATIVE) { 908 rc = -EINVAL; 909 printk(KERN_WARNING "SELinux: defcontext option is " 910 "invalid for this filesystem type\n"); 911 goto out; 912 } 913 914 if (defcontext_sid != sbsec->def_sid) { 915 rc = may_context_mount_inode_relabel(defcontext_sid, 916 sbsec, cred); 917 if (rc) 918 goto out; 919 } 920 921 sbsec->def_sid = defcontext_sid; 922 } 923 924 out_set_opts: 925 rc = sb_finish_set_opts(sb); 926 out: 927 mutex_unlock(&sbsec->lock); 928 return rc; 929 out_double_mount: 930 rc = -EINVAL; 931 printk(KERN_WARNING "SELinux: mount invalid. Same superblock, different " 932 "security settings for (dev %s, type %s)\n", sb->s_id, name); 933 goto out; 934 } 935 936 static int selinux_cmp_sb_context(const struct super_block *oldsb, 937 const struct super_block *newsb) 938 { 939 struct superblock_security_struct *old = oldsb->s_security; 940 struct superblock_security_struct *new = newsb->s_security; 941 char oldflags = old->flags & SE_MNTMASK; 942 char newflags = new->flags & SE_MNTMASK; 943 944 if (oldflags != newflags) 945 goto mismatch; 946 if ((oldflags & FSCONTEXT_MNT) && old->sid != new->sid) 947 goto mismatch; 948 if ((oldflags & CONTEXT_MNT) && old->mntpoint_sid != new->mntpoint_sid) 949 goto mismatch; 950 if ((oldflags & DEFCONTEXT_MNT) && old->def_sid != new->def_sid) 951 goto mismatch; 952 if (oldflags & ROOTCONTEXT_MNT) { 953 struct inode_security_struct *oldroot = backing_inode_security(oldsb->s_root); 954 struct inode_security_struct *newroot = backing_inode_security(newsb->s_root); 955 if (oldroot->sid != newroot->sid) 956 goto mismatch; 957 } 958 return 0; 959 mismatch: 960 printk(KERN_WARNING "SELinux: mount invalid. Same superblock, " 961 "different security settings for (dev %s, " 962 "type %s)\n", newsb->s_id, newsb->s_type->name); 963 return -EBUSY; 964 } 965 966 static int selinux_sb_clone_mnt_opts(const struct super_block *oldsb, 967 struct super_block *newsb) 968 { 969 const struct superblock_security_struct *oldsbsec = oldsb->s_security; 970 struct superblock_security_struct *newsbsec = newsb->s_security; 971 972 int set_fscontext = (oldsbsec->flags & FSCONTEXT_MNT); 973 int set_context = (oldsbsec->flags & CONTEXT_MNT); 974 int set_rootcontext = (oldsbsec->flags & ROOTCONTEXT_MNT); 975 976 /* 977 * if the parent was able to be mounted it clearly had no special lsm 978 * mount options. thus we can safely deal with this superblock later 979 */ 980 if (!ss_initialized) 981 return 0; 982 983 /* how can we clone if the old one wasn't set up?? */ 984 BUG_ON(!(oldsbsec->flags & SE_SBINITIALIZED)); 985 986 /* if fs is reusing a sb, make sure that the contexts match */ 987 if (newsbsec->flags & SE_SBINITIALIZED) 988 return selinux_cmp_sb_context(oldsb, newsb); 989 990 mutex_lock(&newsbsec->lock); 991 992 newsbsec->flags = oldsbsec->flags; 993 994 newsbsec->sid = oldsbsec->sid; 995 newsbsec->def_sid = oldsbsec->def_sid; 996 newsbsec->behavior = oldsbsec->behavior; 997 998 if (set_context) { 999 u32 sid = oldsbsec->mntpoint_sid; 1000 1001 if (!set_fscontext) 1002 newsbsec->sid = sid; 1003 if (!set_rootcontext) { 1004 struct inode_security_struct *newisec = backing_inode_security(newsb->s_root); 1005 newisec->sid = sid; 1006 } 1007 newsbsec->mntpoint_sid = sid; 1008 } 1009 if (set_rootcontext) { 1010 const struct inode_security_struct *oldisec = backing_inode_security(oldsb->s_root); 1011 struct inode_security_struct *newisec = backing_inode_security(newsb->s_root); 1012 1013 newisec->sid = oldisec->sid; 1014 } 1015 1016 sb_finish_set_opts(newsb); 1017 mutex_unlock(&newsbsec->lock); 1018 return 0; 1019 } 1020 1021 static int selinux_parse_opts_str(char *options, 1022 struct security_mnt_opts *opts) 1023 { 1024 char *p; 1025 char *context = NULL, *defcontext = NULL; 1026 char *fscontext = NULL, *rootcontext = NULL; 1027 int rc, num_mnt_opts = 0; 1028 1029 opts->num_mnt_opts = 0; 1030 1031 /* Standard string-based options. */ 1032 while ((p = strsep(&options, "|")) != NULL) { 1033 int token; 1034 substring_t args[MAX_OPT_ARGS]; 1035 1036 if (!*p) 1037 continue; 1038 1039 token = match_token(p, tokens, args); 1040 1041 switch (token) { 1042 case Opt_context: 1043 if (context || defcontext) { 1044 rc = -EINVAL; 1045 printk(KERN_WARNING SEL_MOUNT_FAIL_MSG); 1046 goto out_err; 1047 } 1048 context = match_strdup(&args[0]); 1049 if (!context) { 1050 rc = -ENOMEM; 1051 goto out_err; 1052 } 1053 break; 1054 1055 case Opt_fscontext: 1056 if (fscontext) { 1057 rc = -EINVAL; 1058 printk(KERN_WARNING SEL_MOUNT_FAIL_MSG); 1059 goto out_err; 1060 } 1061 fscontext = match_strdup(&args[0]); 1062 if (!fscontext) { 1063 rc = -ENOMEM; 1064 goto out_err; 1065 } 1066 break; 1067 1068 case Opt_rootcontext: 1069 if (rootcontext) { 1070 rc = -EINVAL; 1071 printk(KERN_WARNING SEL_MOUNT_FAIL_MSG); 1072 goto out_err; 1073 } 1074 rootcontext = match_strdup(&args[0]); 1075 if (!rootcontext) { 1076 rc = -ENOMEM; 1077 goto out_err; 1078 } 1079 break; 1080 1081 case Opt_defcontext: 1082 if (context || defcontext) { 1083 rc = -EINVAL; 1084 printk(KERN_WARNING SEL_MOUNT_FAIL_MSG); 1085 goto out_err; 1086 } 1087 defcontext = match_strdup(&args[0]); 1088 if (!defcontext) { 1089 rc = -ENOMEM; 1090 goto out_err; 1091 } 1092 break; 1093 case Opt_labelsupport: 1094 break; 1095 default: 1096 rc = -EINVAL; 1097 printk(KERN_WARNING "SELinux: unknown mount option\n"); 1098 goto out_err; 1099 1100 } 1101 } 1102 1103 rc = -ENOMEM; 1104 opts->mnt_opts = kcalloc(NUM_SEL_MNT_OPTS, sizeof(char *), GFP_KERNEL); 1105 if (!opts->mnt_opts) 1106 goto out_err; 1107 1108 opts->mnt_opts_flags = kcalloc(NUM_SEL_MNT_OPTS, sizeof(int), 1109 GFP_KERNEL); 1110 if (!opts->mnt_opts_flags) { 1111 kfree(opts->mnt_opts); 1112 goto out_err; 1113 } 1114 1115 if (fscontext) { 1116 opts->mnt_opts[num_mnt_opts] = fscontext; 1117 opts->mnt_opts_flags[num_mnt_opts++] = FSCONTEXT_MNT; 1118 } 1119 if (context) { 1120 opts->mnt_opts[num_mnt_opts] = context; 1121 opts->mnt_opts_flags[num_mnt_opts++] = CONTEXT_MNT; 1122 } 1123 if (rootcontext) { 1124 opts->mnt_opts[num_mnt_opts] = rootcontext; 1125 opts->mnt_opts_flags[num_mnt_opts++] = ROOTCONTEXT_MNT; 1126 } 1127 if (defcontext) { 1128 opts->mnt_opts[num_mnt_opts] = defcontext; 1129 opts->mnt_opts_flags[num_mnt_opts++] = DEFCONTEXT_MNT; 1130 } 1131 1132 opts->num_mnt_opts = num_mnt_opts; 1133 return 0; 1134 1135 out_err: 1136 kfree(context); 1137 kfree(defcontext); 1138 kfree(fscontext); 1139 kfree(rootcontext); 1140 return rc; 1141 } 1142 /* 1143 * string mount options parsing and call set the sbsec 1144 */ 1145 static int superblock_doinit(struct super_block *sb, void *data) 1146 { 1147 int rc = 0; 1148 char *options = data; 1149 struct security_mnt_opts opts; 1150 1151 security_init_mnt_opts(&opts); 1152 1153 if (!data) 1154 goto out; 1155 1156 BUG_ON(sb->s_type->fs_flags & FS_BINARY_MOUNTDATA); 1157 1158 rc = selinux_parse_opts_str(options, &opts); 1159 if (rc) 1160 goto out_err; 1161 1162 out: 1163 rc = selinux_set_mnt_opts(sb, &opts, 0, NULL); 1164 1165 out_err: 1166 security_free_mnt_opts(&opts); 1167 return rc; 1168 } 1169 1170 static void selinux_write_opts(struct seq_file *m, 1171 struct security_mnt_opts *opts) 1172 { 1173 int i; 1174 char *prefix; 1175 1176 for (i = 0; i < opts->num_mnt_opts; i++) { 1177 char *has_comma; 1178 1179 if (opts->mnt_opts[i]) 1180 has_comma = strchr(opts->mnt_opts[i], ','); 1181 else 1182 has_comma = NULL; 1183 1184 switch (opts->mnt_opts_flags[i]) { 1185 case CONTEXT_MNT: 1186 prefix = CONTEXT_STR; 1187 break; 1188 case FSCONTEXT_MNT: 1189 prefix = FSCONTEXT_STR; 1190 break; 1191 case ROOTCONTEXT_MNT: 1192 prefix = ROOTCONTEXT_STR; 1193 break; 1194 case DEFCONTEXT_MNT: 1195 prefix = DEFCONTEXT_STR; 1196 break; 1197 case SBLABEL_MNT: 1198 seq_putc(m, ','); 1199 seq_puts(m, LABELSUPP_STR); 1200 continue; 1201 default: 1202 BUG(); 1203 return; 1204 }; 1205 /* we need a comma before each option */ 1206 seq_putc(m, ','); 1207 seq_puts(m, prefix); 1208 if (has_comma) 1209 seq_putc(m, '\"'); 1210 seq_escape(m, opts->mnt_opts[i], "\"\n\\"); 1211 if (has_comma) 1212 seq_putc(m, '\"'); 1213 } 1214 } 1215 1216 static int selinux_sb_show_options(struct seq_file *m, struct super_block *sb) 1217 { 1218 struct security_mnt_opts opts; 1219 int rc; 1220 1221 rc = selinux_get_mnt_opts(sb, &opts); 1222 if (rc) { 1223 /* before policy load we may get EINVAL, don't show anything */ 1224 if (rc == -EINVAL) 1225 rc = 0; 1226 return rc; 1227 } 1228 1229 selinux_write_opts(m, &opts); 1230 1231 security_free_mnt_opts(&opts); 1232 1233 return rc; 1234 } 1235 1236 static inline u16 inode_mode_to_security_class(umode_t mode) 1237 { 1238 switch (mode & S_IFMT) { 1239 case S_IFSOCK: 1240 return SECCLASS_SOCK_FILE; 1241 case S_IFLNK: 1242 return SECCLASS_LNK_FILE; 1243 case S_IFREG: 1244 return SECCLASS_FILE; 1245 case S_IFBLK: 1246 return SECCLASS_BLK_FILE; 1247 case S_IFDIR: 1248 return SECCLASS_DIR; 1249 case S_IFCHR: 1250 return SECCLASS_CHR_FILE; 1251 case S_IFIFO: 1252 return SECCLASS_FIFO_FILE; 1253 1254 } 1255 1256 return SECCLASS_FILE; 1257 } 1258 1259 static inline int default_protocol_stream(int protocol) 1260 { 1261 return (protocol == IPPROTO_IP || protocol == IPPROTO_TCP); 1262 } 1263 1264 static inline int default_protocol_dgram(int protocol) 1265 { 1266 return (protocol == IPPROTO_IP || protocol == IPPROTO_UDP); 1267 } 1268 1269 static inline u16 socket_type_to_security_class(int family, int type, int protocol) 1270 { 1271 int extsockclass = selinux_policycap_extsockclass; 1272 1273 switch (family) { 1274 case PF_UNIX: 1275 switch (type) { 1276 case SOCK_STREAM: 1277 case SOCK_SEQPACKET: 1278 return SECCLASS_UNIX_STREAM_SOCKET; 1279 case SOCK_DGRAM: 1280 return SECCLASS_UNIX_DGRAM_SOCKET; 1281 } 1282 break; 1283 case PF_INET: 1284 case PF_INET6: 1285 switch (type) { 1286 case SOCK_STREAM: 1287 case SOCK_SEQPACKET: 1288 if (default_protocol_stream(protocol)) 1289 return SECCLASS_TCP_SOCKET; 1290 else if (extsockclass && protocol == IPPROTO_SCTP) 1291 return SECCLASS_SCTP_SOCKET; 1292 else 1293 return SECCLASS_RAWIP_SOCKET; 1294 case SOCK_DGRAM: 1295 if (default_protocol_dgram(protocol)) 1296 return SECCLASS_UDP_SOCKET; 1297 else if (extsockclass && protocol == IPPROTO_ICMP) 1298 return SECCLASS_ICMP_SOCKET; 1299 else 1300 return SECCLASS_RAWIP_SOCKET; 1301 case SOCK_DCCP: 1302 return SECCLASS_DCCP_SOCKET; 1303 default: 1304 return SECCLASS_RAWIP_SOCKET; 1305 } 1306 break; 1307 case PF_NETLINK: 1308 switch (protocol) { 1309 case NETLINK_ROUTE: 1310 return SECCLASS_NETLINK_ROUTE_SOCKET; 1311 case NETLINK_SOCK_DIAG: 1312 return SECCLASS_NETLINK_TCPDIAG_SOCKET; 1313 case NETLINK_NFLOG: 1314 return SECCLASS_NETLINK_NFLOG_SOCKET; 1315 case NETLINK_XFRM: 1316 return SECCLASS_NETLINK_XFRM_SOCKET; 1317 case NETLINK_SELINUX: 1318 return SECCLASS_NETLINK_SELINUX_SOCKET; 1319 case NETLINK_ISCSI: 1320 return SECCLASS_NETLINK_ISCSI_SOCKET; 1321 case NETLINK_AUDIT: 1322 return SECCLASS_NETLINK_AUDIT_SOCKET; 1323 case NETLINK_FIB_LOOKUP: 1324 return SECCLASS_NETLINK_FIB_LOOKUP_SOCKET; 1325 case NETLINK_CONNECTOR: 1326 return SECCLASS_NETLINK_CONNECTOR_SOCKET; 1327 case NETLINK_NETFILTER: 1328 return SECCLASS_NETLINK_NETFILTER_SOCKET; 1329 case NETLINK_DNRTMSG: 1330 return SECCLASS_NETLINK_DNRT_SOCKET; 1331 case NETLINK_KOBJECT_UEVENT: 1332 return SECCLASS_NETLINK_KOBJECT_UEVENT_SOCKET; 1333 case NETLINK_GENERIC: 1334 return SECCLASS_NETLINK_GENERIC_SOCKET; 1335 case NETLINK_SCSITRANSPORT: 1336 return SECCLASS_NETLINK_SCSITRANSPORT_SOCKET; 1337 case NETLINK_RDMA: 1338 return SECCLASS_NETLINK_RDMA_SOCKET; 1339 case NETLINK_CRYPTO: 1340 return SECCLASS_NETLINK_CRYPTO_SOCKET; 1341 default: 1342 return SECCLASS_NETLINK_SOCKET; 1343 } 1344 case PF_PACKET: 1345 return SECCLASS_PACKET_SOCKET; 1346 case PF_KEY: 1347 return SECCLASS_KEY_SOCKET; 1348 case PF_APPLETALK: 1349 return SECCLASS_APPLETALK_SOCKET; 1350 } 1351 1352 if (extsockclass) { 1353 switch (family) { 1354 case PF_AX25: 1355 return SECCLASS_AX25_SOCKET; 1356 case PF_IPX: 1357 return SECCLASS_IPX_SOCKET; 1358 case PF_NETROM: 1359 return SECCLASS_NETROM_SOCKET; 1360 case PF_BRIDGE: 1361 return SECCLASS_BRIDGE_SOCKET; 1362 case PF_ATMPVC: 1363 return SECCLASS_ATMPVC_SOCKET; 1364 case PF_X25: 1365 return SECCLASS_X25_SOCKET; 1366 case PF_ROSE: 1367 return SECCLASS_ROSE_SOCKET; 1368 case PF_DECnet: 1369 return SECCLASS_DECNET_SOCKET; 1370 case PF_ATMSVC: 1371 return SECCLASS_ATMSVC_SOCKET; 1372 case PF_RDS: 1373 return SECCLASS_RDS_SOCKET; 1374 case PF_IRDA: 1375 return SECCLASS_IRDA_SOCKET; 1376 case PF_PPPOX: 1377 return SECCLASS_PPPOX_SOCKET; 1378 case PF_LLC: 1379 return SECCLASS_LLC_SOCKET; 1380 case PF_IB: 1381 return SECCLASS_IB_SOCKET; 1382 case PF_MPLS: 1383 return SECCLASS_MPLS_SOCKET; 1384 case PF_CAN: 1385 return SECCLASS_CAN_SOCKET; 1386 case PF_TIPC: 1387 return SECCLASS_TIPC_SOCKET; 1388 case PF_BLUETOOTH: 1389 return SECCLASS_BLUETOOTH_SOCKET; 1390 case PF_IUCV: 1391 return SECCLASS_IUCV_SOCKET; 1392 case PF_RXRPC: 1393 return SECCLASS_RXRPC_SOCKET; 1394 case PF_ISDN: 1395 return SECCLASS_ISDN_SOCKET; 1396 case PF_PHONET: 1397 return SECCLASS_PHONET_SOCKET; 1398 case PF_IEEE802154: 1399 return SECCLASS_IEEE802154_SOCKET; 1400 case PF_CAIF: 1401 return SECCLASS_CAIF_SOCKET; 1402 case PF_ALG: 1403 return SECCLASS_ALG_SOCKET; 1404 case PF_NFC: 1405 return SECCLASS_NFC_SOCKET; 1406 case PF_VSOCK: 1407 return SECCLASS_VSOCK_SOCKET; 1408 case PF_KCM: 1409 return SECCLASS_KCM_SOCKET; 1410 case PF_QIPCRTR: 1411 return SECCLASS_QIPCRTR_SOCKET; 1412 #if PF_MAX > 43 1413 #error New address family defined, please update this function. 1414 #endif 1415 } 1416 } 1417 1418 return SECCLASS_SOCKET; 1419 } 1420 1421 static int selinux_genfs_get_sid(struct dentry *dentry, 1422 u16 tclass, 1423 u16 flags, 1424 u32 *sid) 1425 { 1426 int rc; 1427 struct super_block *sb = dentry->d_sb; 1428 char *buffer, *path; 1429 1430 buffer = (char *)__get_free_page(GFP_KERNEL); 1431 if (!buffer) 1432 return -ENOMEM; 1433 1434 path = dentry_path_raw(dentry, buffer, PAGE_SIZE); 1435 if (IS_ERR(path)) 1436 rc = PTR_ERR(path); 1437 else { 1438 if (flags & SE_SBPROC) { 1439 /* each process gets a /proc/PID/ entry. Strip off the 1440 * PID part to get a valid selinux labeling. 1441 * e.g. /proc/1/net/rpc/nfs -> /net/rpc/nfs */ 1442 while (path[1] >= '0' && path[1] <= '9') { 1443 path[1] = '/'; 1444 path++; 1445 } 1446 } 1447 rc = security_genfs_sid(sb->s_type->name, path, tclass, sid); 1448 } 1449 free_page((unsigned long)buffer); 1450 return rc; 1451 } 1452 1453 /* The inode's security attributes must be initialized before first use. */ 1454 static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dentry) 1455 { 1456 struct superblock_security_struct *sbsec = NULL; 1457 struct inode_security_struct *isec = inode->i_security; 1458 u32 task_sid, sid = 0; 1459 u16 sclass; 1460 struct dentry *dentry; 1461 #define INITCONTEXTLEN 255 1462 char *context = NULL; 1463 unsigned len = 0; 1464 int rc = 0; 1465 1466 if (isec->initialized == LABEL_INITIALIZED) 1467 return 0; 1468 1469 spin_lock(&isec->lock); 1470 if (isec->initialized == LABEL_INITIALIZED) 1471 goto out_unlock; 1472 1473 if (isec->sclass == SECCLASS_FILE) 1474 isec->sclass = inode_mode_to_security_class(inode->i_mode); 1475 1476 sbsec = inode->i_sb->s_security; 1477 if (!(sbsec->flags & SE_SBINITIALIZED)) { 1478 /* Defer initialization until selinux_complete_init, 1479 after the initial policy is loaded and the security 1480 server is ready to handle calls. */ 1481 spin_lock(&sbsec->isec_lock); 1482 if (list_empty(&isec->list)) 1483 list_add(&isec->list, &sbsec->isec_head); 1484 spin_unlock(&sbsec->isec_lock); 1485 goto out_unlock; 1486 } 1487 1488 sclass = isec->sclass; 1489 task_sid = isec->task_sid; 1490 sid = isec->sid; 1491 isec->initialized = LABEL_PENDING; 1492 spin_unlock(&isec->lock); 1493 1494 switch (sbsec->behavior) { 1495 case SECURITY_FS_USE_NATIVE: 1496 break; 1497 case SECURITY_FS_USE_XATTR: 1498 if (!(inode->i_opflags & IOP_XATTR)) { 1499 sid = sbsec->def_sid; 1500 break; 1501 } 1502 /* Need a dentry, since the xattr API requires one. 1503 Life would be simpler if we could just pass the inode. */ 1504 if (opt_dentry) { 1505 /* Called from d_instantiate or d_splice_alias. */ 1506 dentry = dget(opt_dentry); 1507 } else { 1508 /* Called from selinux_complete_init, try to find a dentry. */ 1509 dentry = d_find_alias(inode); 1510 } 1511 if (!dentry) { 1512 /* 1513 * this is can be hit on boot when a file is accessed 1514 * before the policy is loaded. When we load policy we 1515 * may find inodes that have no dentry on the 1516 * sbsec->isec_head list. No reason to complain as these 1517 * will get fixed up the next time we go through 1518 * inode_doinit with a dentry, before these inodes could 1519 * be used again by userspace. 1520 */ 1521 goto out; 1522 } 1523 1524 len = INITCONTEXTLEN; 1525 context = kmalloc(len+1, GFP_NOFS); 1526 if (!context) { 1527 rc = -ENOMEM; 1528 dput(dentry); 1529 goto out; 1530 } 1531 context[len] = '\0'; 1532 rc = __vfs_getxattr(dentry, inode, XATTR_NAME_SELINUX, context, len); 1533 if (rc == -ERANGE) { 1534 kfree(context); 1535 1536 /* Need a larger buffer. Query for the right size. */ 1537 rc = __vfs_getxattr(dentry, inode, XATTR_NAME_SELINUX, NULL, 0); 1538 if (rc < 0) { 1539 dput(dentry); 1540 goto out; 1541 } 1542 len = rc; 1543 context = kmalloc(len+1, GFP_NOFS); 1544 if (!context) { 1545 rc = -ENOMEM; 1546 dput(dentry); 1547 goto out; 1548 } 1549 context[len] = '\0'; 1550 rc = __vfs_getxattr(dentry, inode, XATTR_NAME_SELINUX, context, len); 1551 } 1552 dput(dentry); 1553 if (rc < 0) { 1554 if (rc != -ENODATA) { 1555 printk(KERN_WARNING "SELinux: %s: getxattr returned " 1556 "%d for dev=%s ino=%ld\n", __func__, 1557 -rc, inode->i_sb->s_id, inode->i_ino); 1558 kfree(context); 1559 goto out; 1560 } 1561 /* Map ENODATA to the default file SID */ 1562 sid = sbsec->def_sid; 1563 rc = 0; 1564 } else { 1565 rc = security_context_to_sid_default(context, rc, &sid, 1566 sbsec->def_sid, 1567 GFP_NOFS); 1568 if (rc) { 1569 char *dev = inode->i_sb->s_id; 1570 unsigned long ino = inode->i_ino; 1571 1572 if (rc == -EINVAL) { 1573 if (printk_ratelimit()) 1574 printk(KERN_NOTICE "SELinux: inode=%lu on dev=%s was found to have an invalid " 1575 "context=%s. This indicates you may need to relabel the inode or the " 1576 "filesystem in question.\n", ino, dev, context); 1577 } else { 1578 printk(KERN_WARNING "SELinux: %s: context_to_sid(%s) " 1579 "returned %d for dev=%s ino=%ld\n", 1580 __func__, context, -rc, dev, ino); 1581 } 1582 kfree(context); 1583 /* Leave with the unlabeled SID */ 1584 rc = 0; 1585 break; 1586 } 1587 } 1588 kfree(context); 1589 break; 1590 case SECURITY_FS_USE_TASK: 1591 sid = task_sid; 1592 break; 1593 case SECURITY_FS_USE_TRANS: 1594 /* Default to the fs SID. */ 1595 sid = sbsec->sid; 1596 1597 /* Try to obtain a transition SID. */ 1598 rc = security_transition_sid(task_sid, sid, sclass, NULL, &sid); 1599 if (rc) 1600 goto out; 1601 break; 1602 case SECURITY_FS_USE_MNTPOINT: 1603 sid = sbsec->mntpoint_sid; 1604 break; 1605 default: 1606 /* Default to the fs superblock SID. */ 1607 sid = sbsec->sid; 1608 1609 if ((sbsec->flags & SE_SBGENFS) && !S_ISLNK(inode->i_mode)) { 1610 /* We must have a dentry to determine the label on 1611 * procfs inodes */ 1612 if (opt_dentry) 1613 /* Called from d_instantiate or 1614 * d_splice_alias. */ 1615 dentry = dget(opt_dentry); 1616 else 1617 /* Called from selinux_complete_init, try to 1618 * find a dentry. */ 1619 dentry = d_find_alias(inode); 1620 /* 1621 * This can be hit on boot when a file is accessed 1622 * before the policy is loaded. When we load policy we 1623 * may find inodes that have no dentry on the 1624 * sbsec->isec_head list. No reason to complain as 1625 * these will get fixed up the next time we go through 1626 * inode_doinit() with a dentry, before these inodes 1627 * could be used again by userspace. 1628 */ 1629 if (!dentry) 1630 goto out; 1631 rc = selinux_genfs_get_sid(dentry, sclass, 1632 sbsec->flags, &sid); 1633 dput(dentry); 1634 if (rc) 1635 goto out; 1636 } 1637 break; 1638 } 1639 1640 out: 1641 spin_lock(&isec->lock); 1642 if (isec->initialized == LABEL_PENDING) { 1643 if (!sid || rc) { 1644 isec->initialized = LABEL_INVALID; 1645 goto out_unlock; 1646 } 1647 1648 isec->initialized = LABEL_INITIALIZED; 1649 isec->sid = sid; 1650 } 1651 1652 out_unlock: 1653 spin_unlock(&isec->lock); 1654 return rc; 1655 } 1656 1657 /* Convert a Linux signal to an access vector. */ 1658 static inline u32 signal_to_av(int sig) 1659 { 1660 u32 perm = 0; 1661 1662 switch (sig) { 1663 case SIGCHLD: 1664 /* Commonly granted from child to parent. */ 1665 perm = PROCESS__SIGCHLD; 1666 break; 1667 case SIGKILL: 1668 /* Cannot be caught or ignored */ 1669 perm = PROCESS__SIGKILL; 1670 break; 1671 case SIGSTOP: 1672 /* Cannot be caught or ignored */ 1673 perm = PROCESS__SIGSTOP; 1674 break; 1675 default: 1676 /* All other signals. */ 1677 perm = PROCESS__SIGNAL; 1678 break; 1679 } 1680 1681 return perm; 1682 } 1683 1684 /* 1685 * Check permission between a pair of credentials 1686 * fork check, ptrace check, etc. 1687 */ 1688 static int cred_has_perm(const struct cred *actor, 1689 const struct cred *target, 1690 u32 perms) 1691 { 1692 u32 asid = cred_sid(actor), tsid = cred_sid(target); 1693 1694 return avc_has_perm(asid, tsid, SECCLASS_PROCESS, perms, NULL); 1695 } 1696 1697 /* 1698 * Check permission between a pair of tasks, e.g. signal checks, 1699 * fork check, ptrace check, etc. 1700 * tsk1 is the actor and tsk2 is the target 1701 * - this uses the default subjective creds of tsk1 1702 */ 1703 static int task_has_perm(const struct task_struct *tsk1, 1704 const struct task_struct *tsk2, 1705 u32 perms) 1706 { 1707 const struct task_security_struct *__tsec1, *__tsec2; 1708 u32 sid1, sid2; 1709 1710 rcu_read_lock(); 1711 __tsec1 = __task_cred(tsk1)->security; sid1 = __tsec1->sid; 1712 __tsec2 = __task_cred(tsk2)->security; sid2 = __tsec2->sid; 1713 rcu_read_unlock(); 1714 return avc_has_perm(sid1, sid2, SECCLASS_PROCESS, perms, NULL); 1715 } 1716 1717 /* 1718 * Check permission between current and another task, e.g. signal checks, 1719 * fork check, ptrace check, etc. 1720 * current is the actor and tsk2 is the target 1721 * - this uses current's subjective creds 1722 */ 1723 static int current_has_perm(const struct task_struct *tsk, 1724 u32 perms) 1725 { 1726 u32 sid, tsid; 1727 1728 sid = current_sid(); 1729 tsid = task_sid(tsk); 1730 return avc_has_perm(sid, tsid, SECCLASS_PROCESS, perms, NULL); 1731 } 1732 1733 #if CAP_LAST_CAP > 63 1734 #error Fix SELinux to handle capabilities > 63. 1735 #endif 1736 1737 /* Check whether a task is allowed to use a capability. */ 1738 static int cred_has_capability(const struct cred *cred, 1739 int cap, int audit, bool initns) 1740 { 1741 struct common_audit_data ad; 1742 struct av_decision avd; 1743 u16 sclass; 1744 u32 sid = cred_sid(cred); 1745 u32 av = CAP_TO_MASK(cap); 1746 int rc; 1747 1748 ad.type = LSM_AUDIT_DATA_CAP; 1749 ad.u.cap = cap; 1750 1751 switch (CAP_TO_INDEX(cap)) { 1752 case 0: 1753 sclass = initns ? SECCLASS_CAPABILITY : SECCLASS_CAP_USERNS; 1754 break; 1755 case 1: 1756 sclass = initns ? SECCLASS_CAPABILITY2 : SECCLASS_CAP2_USERNS; 1757 break; 1758 default: 1759 printk(KERN_ERR 1760 "SELinux: out of range capability %d\n", cap); 1761 BUG(); 1762 return -EINVAL; 1763 } 1764 1765 rc = avc_has_perm_noaudit(sid, sid, sclass, av, 0, &avd); 1766 if (audit == SECURITY_CAP_AUDIT) { 1767 int rc2 = avc_audit(sid, sid, sclass, av, &avd, rc, &ad, 0); 1768 if (rc2) 1769 return rc2; 1770 } 1771 return rc; 1772 } 1773 1774 /* Check whether a task is allowed to use a system operation. */ 1775 static int task_has_system(struct task_struct *tsk, 1776 u32 perms) 1777 { 1778 u32 sid = task_sid(tsk); 1779 1780 return avc_has_perm(sid, SECINITSID_KERNEL, 1781 SECCLASS_SYSTEM, perms, NULL); 1782 } 1783 1784 /* Check whether a task has a particular permission to an inode. 1785 The 'adp' parameter is optional and allows other audit 1786 data to be passed (e.g. the dentry). */ 1787 static int inode_has_perm(const struct cred *cred, 1788 struct inode *inode, 1789 u32 perms, 1790 struct common_audit_data *adp) 1791 { 1792 struct inode_security_struct *isec; 1793 u32 sid; 1794 1795 validate_creds(cred); 1796 1797 if (unlikely(IS_PRIVATE(inode))) 1798 return 0; 1799 1800 sid = cred_sid(cred); 1801 isec = inode->i_security; 1802 1803 return avc_has_perm(sid, isec->sid, isec->sclass, perms, adp); 1804 } 1805 1806 /* Same as inode_has_perm, but pass explicit audit data containing 1807 the dentry to help the auditing code to more easily generate the 1808 pathname if needed. */ 1809 static inline int dentry_has_perm(const struct cred *cred, 1810 struct dentry *dentry, 1811 u32 av) 1812 { 1813 struct inode *inode = d_backing_inode(dentry); 1814 struct common_audit_data ad; 1815 1816 ad.type = LSM_AUDIT_DATA_DENTRY; 1817 ad.u.dentry = dentry; 1818 __inode_security_revalidate(inode, dentry, true); 1819 return inode_has_perm(cred, inode, av, &ad); 1820 } 1821 1822 /* Same as inode_has_perm, but pass explicit audit data containing 1823 the path to help the auditing code to more easily generate the 1824 pathname if needed. */ 1825 static inline int path_has_perm(const struct cred *cred, 1826 const struct path *path, 1827 u32 av) 1828 { 1829 struct inode *inode = d_backing_inode(path->dentry); 1830 struct common_audit_data ad; 1831 1832 ad.type = LSM_AUDIT_DATA_PATH; 1833 ad.u.path = *path; 1834 __inode_security_revalidate(inode, path->dentry, true); 1835 return inode_has_perm(cred, inode, av, &ad); 1836 } 1837 1838 /* Same as path_has_perm, but uses the inode from the file struct. */ 1839 static inline int file_path_has_perm(const struct cred *cred, 1840 struct file *file, 1841 u32 av) 1842 { 1843 struct common_audit_data ad; 1844 1845 ad.type = LSM_AUDIT_DATA_FILE; 1846 ad.u.file = file; 1847 return inode_has_perm(cred, file_inode(file), av, &ad); 1848 } 1849 1850 /* Check whether a task can use an open file descriptor to 1851 access an inode in a given way. Check access to the 1852 descriptor itself, and then use dentry_has_perm to 1853 check a particular permission to the file. 1854 Access to the descriptor is implicitly granted if it 1855 has the same SID as the process. If av is zero, then 1856 access to the file is not checked, e.g. for cases 1857 where only the descriptor is affected like seek. */ 1858 static int file_has_perm(const struct cred *cred, 1859 struct file *file, 1860 u32 av) 1861 { 1862 struct file_security_struct *fsec = file->f_security; 1863 struct inode *inode = file_inode(file); 1864 struct common_audit_data ad; 1865 u32 sid = cred_sid(cred); 1866 int rc; 1867 1868 ad.type = LSM_AUDIT_DATA_FILE; 1869 ad.u.file = file; 1870 1871 if (sid != fsec->sid) { 1872 rc = avc_has_perm(sid, fsec->sid, 1873 SECCLASS_FD, 1874 FD__USE, 1875 &ad); 1876 if (rc) 1877 goto out; 1878 } 1879 1880 /* av is zero if only checking access to the descriptor. */ 1881 rc = 0; 1882 if (av) 1883 rc = inode_has_perm(cred, inode, av, &ad); 1884 1885 out: 1886 return rc; 1887 } 1888 1889 /* 1890 * Determine the label for an inode that might be unioned. 1891 */ 1892 static int 1893 selinux_determine_inode_label(const struct task_security_struct *tsec, 1894 struct inode *dir, 1895 const struct qstr *name, u16 tclass, 1896 u32 *_new_isid) 1897 { 1898 const struct superblock_security_struct *sbsec = dir->i_sb->s_security; 1899 1900 if ((sbsec->flags & SE_SBINITIALIZED) && 1901 (sbsec->behavior == SECURITY_FS_USE_MNTPOINT)) { 1902 *_new_isid = sbsec->mntpoint_sid; 1903 } else if ((sbsec->flags & SBLABEL_MNT) && 1904 tsec->create_sid) { 1905 *_new_isid = tsec->create_sid; 1906 } else { 1907 const struct inode_security_struct *dsec = inode_security(dir); 1908 return security_transition_sid(tsec->sid, dsec->sid, tclass, 1909 name, _new_isid); 1910 } 1911 1912 return 0; 1913 } 1914 1915 /* Check whether a task can create a file. */ 1916 static int may_create(struct inode *dir, 1917 struct dentry *dentry, 1918 u16 tclass) 1919 { 1920 const struct task_security_struct *tsec = current_security(); 1921 struct inode_security_struct *dsec; 1922 struct superblock_security_struct *sbsec; 1923 u32 sid, newsid; 1924 struct common_audit_data ad; 1925 int rc; 1926 1927 dsec = inode_security(dir); 1928 sbsec = dir->i_sb->s_security; 1929 1930 sid = tsec->sid; 1931 1932 ad.type = LSM_AUDIT_DATA_DENTRY; 1933 ad.u.dentry = dentry; 1934 1935 rc = avc_has_perm(sid, dsec->sid, SECCLASS_DIR, 1936 DIR__ADD_NAME | DIR__SEARCH, 1937 &ad); 1938 if (rc) 1939 return rc; 1940 1941 rc = selinux_determine_inode_label(current_security(), dir, 1942 &dentry->d_name, tclass, &newsid); 1943 if (rc) 1944 return rc; 1945 1946 rc = avc_has_perm(sid, newsid, tclass, FILE__CREATE, &ad); 1947 if (rc) 1948 return rc; 1949 1950 return avc_has_perm(newsid, sbsec->sid, 1951 SECCLASS_FILESYSTEM, 1952 FILESYSTEM__ASSOCIATE, &ad); 1953 } 1954 1955 /* Check whether a task can create a key. */ 1956 static int may_create_key(u32 ksid, 1957 struct task_struct *ctx) 1958 { 1959 u32 sid = task_sid(ctx); 1960 1961 return avc_has_perm(sid, ksid, SECCLASS_KEY, KEY__CREATE, NULL); 1962 } 1963 1964 #define MAY_LINK 0 1965 #define MAY_UNLINK 1 1966 #define MAY_RMDIR 2 1967 1968 /* Check whether a task can link, unlink, or rmdir a file/directory. */ 1969 static int may_link(struct inode *dir, 1970 struct dentry *dentry, 1971 int kind) 1972 1973 { 1974 struct inode_security_struct *dsec, *isec; 1975 struct common_audit_data ad; 1976 u32 sid = current_sid(); 1977 u32 av; 1978 int rc; 1979 1980 dsec = inode_security(dir); 1981 isec = backing_inode_security(dentry); 1982 1983 ad.type = LSM_AUDIT_DATA_DENTRY; 1984 ad.u.dentry = dentry; 1985 1986 av = DIR__SEARCH; 1987 av |= (kind ? DIR__REMOVE_NAME : DIR__ADD_NAME); 1988 rc = avc_has_perm(sid, dsec->sid, SECCLASS_DIR, av, &ad); 1989 if (rc) 1990 return rc; 1991 1992 switch (kind) { 1993 case MAY_LINK: 1994 av = FILE__LINK; 1995 break; 1996 case MAY_UNLINK: 1997 av = FILE__UNLINK; 1998 break; 1999 case MAY_RMDIR: 2000 av = DIR__RMDIR; 2001 break; 2002 default: 2003 printk(KERN_WARNING "SELinux: %s: unrecognized kind %d\n", 2004 __func__, kind); 2005 return 0; 2006 } 2007 2008 rc = avc_has_perm(sid, isec->sid, isec->sclass, av, &ad); 2009 return rc; 2010 } 2011 2012 static inline int may_rename(struct inode *old_dir, 2013 struct dentry *old_dentry, 2014 struct inode *new_dir, 2015 struct dentry *new_dentry) 2016 { 2017 struct inode_security_struct *old_dsec, *new_dsec, *old_isec, *new_isec; 2018 struct common_audit_data ad; 2019 u32 sid = current_sid(); 2020 u32 av; 2021 int old_is_dir, new_is_dir; 2022 int rc; 2023 2024 old_dsec = inode_security(old_dir); 2025 old_isec = backing_inode_security(old_dentry); 2026 old_is_dir = d_is_dir(old_dentry); 2027 new_dsec = inode_security(new_dir); 2028 2029 ad.type = LSM_AUDIT_DATA_DENTRY; 2030 2031 ad.u.dentry = old_dentry; 2032 rc = avc_has_perm(sid, old_dsec->sid, SECCLASS_DIR, 2033 DIR__REMOVE_NAME | DIR__SEARCH, &ad); 2034 if (rc) 2035 return rc; 2036 rc = avc_has_perm(sid, old_isec->sid, 2037 old_isec->sclass, FILE__RENAME, &ad); 2038 if (rc) 2039 return rc; 2040 if (old_is_dir && new_dir != old_dir) { 2041 rc = avc_has_perm(sid, old_isec->sid, 2042 old_isec->sclass, DIR__REPARENT, &ad); 2043 if (rc) 2044 return rc; 2045 } 2046 2047 ad.u.dentry = new_dentry; 2048 av = DIR__ADD_NAME | DIR__SEARCH; 2049 if (d_is_positive(new_dentry)) 2050 av |= DIR__REMOVE_NAME; 2051 rc = avc_has_perm(sid, new_dsec->sid, SECCLASS_DIR, av, &ad); 2052 if (rc) 2053 return rc; 2054 if (d_is_positive(new_dentry)) { 2055 new_isec = backing_inode_security(new_dentry); 2056 new_is_dir = d_is_dir(new_dentry); 2057 rc = avc_has_perm(sid, new_isec->sid, 2058 new_isec->sclass, 2059 (new_is_dir ? DIR__RMDIR : FILE__UNLINK), &ad); 2060 if (rc) 2061 return rc; 2062 } 2063 2064 return 0; 2065 } 2066 2067 /* Check whether a task can perform a filesystem operation. */ 2068 static int superblock_has_perm(const struct cred *cred, 2069 struct super_block *sb, 2070 u32 perms, 2071 struct common_audit_data *ad) 2072 { 2073 struct superblock_security_struct *sbsec; 2074 u32 sid = cred_sid(cred); 2075 2076 sbsec = sb->s_security; 2077 return avc_has_perm(sid, sbsec->sid, SECCLASS_FILESYSTEM, perms, ad); 2078 } 2079 2080 /* Convert a Linux mode and permission mask to an access vector. */ 2081 static inline u32 file_mask_to_av(int mode, int mask) 2082 { 2083 u32 av = 0; 2084 2085 if (!S_ISDIR(mode)) { 2086 if (mask & MAY_EXEC) 2087 av |= FILE__EXECUTE; 2088 if (mask & MAY_READ) 2089 av |= FILE__READ; 2090 2091 if (mask & MAY_APPEND) 2092 av |= FILE__APPEND; 2093 else if (mask & MAY_WRITE) 2094 av |= FILE__WRITE; 2095 2096 } else { 2097 if (mask & MAY_EXEC) 2098 av |= DIR__SEARCH; 2099 if (mask & MAY_WRITE) 2100 av |= DIR__WRITE; 2101 if (mask & MAY_READ) 2102 av |= DIR__READ; 2103 } 2104 2105 return av; 2106 } 2107 2108 /* Convert a Linux file to an access vector. */ 2109 static inline u32 file_to_av(struct file *file) 2110 { 2111 u32 av = 0; 2112 2113 if (file->f_mode & FMODE_READ) 2114 av |= FILE__READ; 2115 if (file->f_mode & FMODE_WRITE) { 2116 if (file->f_flags & O_APPEND) 2117 av |= FILE__APPEND; 2118 else 2119 av |= FILE__WRITE; 2120 } 2121 if (!av) { 2122 /* 2123 * Special file opened with flags 3 for ioctl-only use. 2124 */ 2125 av = FILE__IOCTL; 2126 } 2127 2128 return av; 2129 } 2130 2131 /* 2132 * Convert a file to an access vector and include the correct open 2133 * open permission. 2134 */ 2135 static inline u32 open_file_to_av(struct file *file) 2136 { 2137 u32 av = file_to_av(file); 2138 2139 if (selinux_policycap_openperm) 2140 av |= FILE__OPEN; 2141 2142 return av; 2143 } 2144 2145 /* Hook functions begin here. */ 2146 2147 static int selinux_binder_set_context_mgr(struct task_struct *mgr) 2148 { 2149 u32 mysid = current_sid(); 2150 u32 mgrsid = task_sid(mgr); 2151 2152 return avc_has_perm(mysid, mgrsid, SECCLASS_BINDER, 2153 BINDER__SET_CONTEXT_MGR, NULL); 2154 } 2155 2156 static int selinux_binder_transaction(struct task_struct *from, 2157 struct task_struct *to) 2158 { 2159 u32 mysid = current_sid(); 2160 u32 fromsid = task_sid(from); 2161 u32 tosid = task_sid(to); 2162 int rc; 2163 2164 if (mysid != fromsid) { 2165 rc = avc_has_perm(mysid, fromsid, SECCLASS_BINDER, 2166 BINDER__IMPERSONATE, NULL); 2167 if (rc) 2168 return rc; 2169 } 2170 2171 return avc_has_perm(fromsid, tosid, SECCLASS_BINDER, BINDER__CALL, 2172 NULL); 2173 } 2174 2175 static int selinux_binder_transfer_binder(struct task_struct *from, 2176 struct task_struct *to) 2177 { 2178 u32 fromsid = task_sid(from); 2179 u32 tosid = task_sid(to); 2180 2181 return avc_has_perm(fromsid, tosid, SECCLASS_BINDER, BINDER__TRANSFER, 2182 NULL); 2183 } 2184 2185 static int selinux_binder_transfer_file(struct task_struct *from, 2186 struct task_struct *to, 2187 struct file *file) 2188 { 2189 u32 sid = task_sid(to); 2190 struct file_security_struct *fsec = file->f_security; 2191 struct dentry *dentry = file->f_path.dentry; 2192 struct inode_security_struct *isec; 2193 struct common_audit_data ad; 2194 int rc; 2195 2196 ad.type = LSM_AUDIT_DATA_PATH; 2197 ad.u.path = file->f_path; 2198 2199 if (sid != fsec->sid) { 2200 rc = avc_has_perm(sid, fsec->sid, 2201 SECCLASS_FD, 2202 FD__USE, 2203 &ad); 2204 if (rc) 2205 return rc; 2206 } 2207 2208 if (unlikely(IS_PRIVATE(d_backing_inode(dentry)))) 2209 return 0; 2210 2211 isec = backing_inode_security(dentry); 2212 return avc_has_perm(sid, isec->sid, isec->sclass, file_to_av(file), 2213 &ad); 2214 } 2215 2216 static int selinux_ptrace_access_check(struct task_struct *child, 2217 unsigned int mode) 2218 { 2219 if (mode & PTRACE_MODE_READ) { 2220 u32 sid = current_sid(); 2221 u32 csid = task_sid(child); 2222 return avc_has_perm(sid, csid, SECCLASS_FILE, FILE__READ, NULL); 2223 } 2224 2225 return current_has_perm(child, PROCESS__PTRACE); 2226 } 2227 2228 static int selinux_ptrace_traceme(struct task_struct *parent) 2229 { 2230 return task_has_perm(parent, current, PROCESS__PTRACE); 2231 } 2232 2233 static int selinux_capget(struct task_struct *target, kernel_cap_t *effective, 2234 kernel_cap_t *inheritable, kernel_cap_t *permitted) 2235 { 2236 return current_has_perm(target, PROCESS__GETCAP); 2237 } 2238 2239 static int selinux_capset(struct cred *new, const struct cred *old, 2240 const kernel_cap_t *effective, 2241 const kernel_cap_t *inheritable, 2242 const kernel_cap_t *permitted) 2243 { 2244 return cred_has_perm(old, new, PROCESS__SETCAP); 2245 } 2246 2247 /* 2248 * (This comment used to live with the selinux_task_setuid hook, 2249 * which was removed). 2250 * 2251 * Since setuid only affects the current process, and since the SELinux 2252 * controls are not based on the Linux identity attributes, SELinux does not 2253 * need to control this operation. However, SELinux does control the use of 2254 * the CAP_SETUID and CAP_SETGID capabilities using the capable hook. 2255 */ 2256 2257 static int selinux_capable(const struct cred *cred, struct user_namespace *ns, 2258 int cap, int audit) 2259 { 2260 return cred_has_capability(cred, cap, audit, ns == &init_user_ns); 2261 } 2262 2263 static int selinux_quotactl(int cmds, int type, int id, struct super_block *sb) 2264 { 2265 const struct cred *cred = current_cred(); 2266 int rc = 0; 2267 2268 if (!sb) 2269 return 0; 2270 2271 switch (cmds) { 2272 case Q_SYNC: 2273 case Q_QUOTAON: 2274 case Q_QUOTAOFF: 2275 case Q_SETINFO: 2276 case Q_SETQUOTA: 2277 rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAMOD, NULL); 2278 break; 2279 case Q_GETFMT: 2280 case Q_GETINFO: 2281 case Q_GETQUOTA: 2282 rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAGET, NULL); 2283 break; 2284 default: 2285 rc = 0; /* let the kernel handle invalid cmds */ 2286 break; 2287 } 2288 return rc; 2289 } 2290 2291 static int selinux_quota_on(struct dentry *dentry) 2292 { 2293 const struct cred *cred = current_cred(); 2294 2295 return dentry_has_perm(cred, dentry, FILE__QUOTAON); 2296 } 2297 2298 static int selinux_syslog(int type) 2299 { 2300 int rc; 2301 2302 switch (type) { 2303 case SYSLOG_ACTION_READ_ALL: /* Read last kernel messages */ 2304 case SYSLOG_ACTION_SIZE_BUFFER: /* Return size of the log buffer */ 2305 rc = task_has_system(current, SYSTEM__SYSLOG_READ); 2306 break; 2307 case SYSLOG_ACTION_CONSOLE_OFF: /* Disable logging to console */ 2308 case SYSLOG_ACTION_CONSOLE_ON: /* Enable logging to console */ 2309 /* Set level of messages printed to console */ 2310 case SYSLOG_ACTION_CONSOLE_LEVEL: 2311 rc = task_has_system(current, SYSTEM__SYSLOG_CONSOLE); 2312 break; 2313 case SYSLOG_ACTION_CLOSE: /* Close log */ 2314 case SYSLOG_ACTION_OPEN: /* Open log */ 2315 case SYSLOG_ACTION_READ: /* Read from log */ 2316 case SYSLOG_ACTION_READ_CLEAR: /* Read/clear last kernel messages */ 2317 case SYSLOG_ACTION_CLEAR: /* Clear ring buffer */ 2318 default: 2319 rc = task_has_system(current, SYSTEM__SYSLOG_MOD); 2320 break; 2321 } 2322 return rc; 2323 } 2324 2325 /* 2326 * Check that a process has enough memory to allocate a new virtual 2327 * mapping. 0 means there is enough memory for the allocation to 2328 * succeed and -ENOMEM implies there is not. 2329 * 2330 * Do not audit the selinux permission check, as this is applied to all 2331 * processes that allocate mappings. 2332 */ 2333 static int selinux_vm_enough_memory(struct mm_struct *mm, long pages) 2334 { 2335 int rc, cap_sys_admin = 0; 2336 2337 rc = cred_has_capability(current_cred(), CAP_SYS_ADMIN, 2338 SECURITY_CAP_NOAUDIT, true); 2339 if (rc == 0) 2340 cap_sys_admin = 1; 2341 2342 return cap_sys_admin; 2343 } 2344 2345 /* binprm security operations */ 2346 2347 static u32 ptrace_parent_sid(struct task_struct *task) 2348 { 2349 u32 sid = 0; 2350 struct task_struct *tracer; 2351 2352 rcu_read_lock(); 2353 tracer = ptrace_parent(task); 2354 if (tracer) 2355 sid = task_sid(tracer); 2356 rcu_read_unlock(); 2357 2358 return sid; 2359 } 2360 2361 static int check_nnp_nosuid(const struct linux_binprm *bprm, 2362 const struct task_security_struct *old_tsec, 2363 const struct task_security_struct *new_tsec) 2364 { 2365 int nnp = (bprm->unsafe & LSM_UNSAFE_NO_NEW_PRIVS); 2366 int nosuid = !mnt_may_suid(bprm->file->f_path.mnt); 2367 int rc; 2368 2369 if (!nnp && !nosuid) 2370 return 0; /* neither NNP nor nosuid */ 2371 2372 if (new_tsec->sid == old_tsec->sid) 2373 return 0; /* No change in credentials */ 2374 2375 /* 2376 * The only transitions we permit under NNP or nosuid 2377 * are transitions to bounded SIDs, i.e. SIDs that are 2378 * guaranteed to only be allowed a subset of the permissions 2379 * of the current SID. 2380 */ 2381 rc = security_bounded_transition(old_tsec->sid, new_tsec->sid); 2382 if (rc) { 2383 /* 2384 * On failure, preserve the errno values for NNP vs nosuid. 2385 * NNP: Operation not permitted for caller. 2386 * nosuid: Permission denied to file. 2387 */ 2388 if (nnp) 2389 return -EPERM; 2390 else 2391 return -EACCES; 2392 } 2393 return 0; 2394 } 2395 2396 static int selinux_bprm_set_creds(struct linux_binprm *bprm) 2397 { 2398 const struct task_security_struct *old_tsec; 2399 struct task_security_struct *new_tsec; 2400 struct inode_security_struct *isec; 2401 struct common_audit_data ad; 2402 struct inode *inode = file_inode(bprm->file); 2403 int rc; 2404 2405 /* SELinux context only depends on initial program or script and not 2406 * the script interpreter */ 2407 if (bprm->cred_prepared) 2408 return 0; 2409 2410 old_tsec = current_security(); 2411 new_tsec = bprm->cred->security; 2412 isec = inode_security(inode); 2413 2414 /* Default to the current task SID. */ 2415 new_tsec->sid = old_tsec->sid; 2416 new_tsec->osid = old_tsec->sid; 2417 2418 /* Reset fs, key, and sock SIDs on execve. */ 2419 new_tsec->create_sid = 0; 2420 new_tsec->keycreate_sid = 0; 2421 new_tsec->sockcreate_sid = 0; 2422 2423 if (old_tsec->exec_sid) { 2424 new_tsec->sid = old_tsec->exec_sid; 2425 /* Reset exec SID on execve. */ 2426 new_tsec->exec_sid = 0; 2427 2428 /* Fail on NNP or nosuid if not an allowed transition. */ 2429 rc = check_nnp_nosuid(bprm, old_tsec, new_tsec); 2430 if (rc) 2431 return rc; 2432 } else { 2433 /* Check for a default transition on this program. */ 2434 rc = security_transition_sid(old_tsec->sid, isec->sid, 2435 SECCLASS_PROCESS, NULL, 2436 &new_tsec->sid); 2437 if (rc) 2438 return rc; 2439 2440 /* 2441 * Fallback to old SID on NNP or nosuid if not an allowed 2442 * transition. 2443 */ 2444 rc = check_nnp_nosuid(bprm, old_tsec, new_tsec); 2445 if (rc) 2446 new_tsec->sid = old_tsec->sid; 2447 } 2448 2449 ad.type = LSM_AUDIT_DATA_FILE; 2450 ad.u.file = bprm->file; 2451 2452 if (new_tsec->sid == old_tsec->sid) { 2453 rc = avc_has_perm(old_tsec->sid, isec->sid, 2454 SECCLASS_FILE, FILE__EXECUTE_NO_TRANS, &ad); 2455 if (rc) 2456 return rc; 2457 } else { 2458 /* Check permissions for the transition. */ 2459 rc = avc_has_perm(old_tsec->sid, new_tsec->sid, 2460 SECCLASS_PROCESS, PROCESS__TRANSITION, &ad); 2461 if (rc) 2462 return rc; 2463 2464 rc = avc_has_perm(new_tsec->sid, isec->sid, 2465 SECCLASS_FILE, FILE__ENTRYPOINT, &ad); 2466 if (rc) 2467 return rc; 2468 2469 /* Check for shared state */ 2470 if (bprm->unsafe & LSM_UNSAFE_SHARE) { 2471 rc = avc_has_perm(old_tsec->sid, new_tsec->sid, 2472 SECCLASS_PROCESS, PROCESS__SHARE, 2473 NULL); 2474 if (rc) 2475 return -EPERM; 2476 } 2477 2478 /* Make sure that anyone attempting to ptrace over a task that 2479 * changes its SID has the appropriate permit */ 2480 if (bprm->unsafe & 2481 (LSM_UNSAFE_PTRACE | LSM_UNSAFE_PTRACE_CAP)) { 2482 u32 ptsid = ptrace_parent_sid(current); 2483 if (ptsid != 0) { 2484 rc = avc_has_perm(ptsid, new_tsec->sid, 2485 SECCLASS_PROCESS, 2486 PROCESS__PTRACE, NULL); 2487 if (rc) 2488 return -EPERM; 2489 } 2490 } 2491 2492 /* Clear any possibly unsafe personality bits on exec: */ 2493 bprm->per_clear |= PER_CLEAR_ON_SETID; 2494 } 2495 2496 return 0; 2497 } 2498 2499 static int selinux_bprm_secureexec(struct linux_binprm *bprm) 2500 { 2501 const struct task_security_struct *tsec = current_security(); 2502 u32 sid, osid; 2503 int atsecure = 0; 2504 2505 sid = tsec->sid; 2506 osid = tsec->osid; 2507 2508 if (osid != sid) { 2509 /* Enable secure mode for SIDs transitions unless 2510 the noatsecure permission is granted between 2511 the two SIDs, i.e. ahp returns 0. */ 2512 atsecure = avc_has_perm(osid, sid, 2513 SECCLASS_PROCESS, 2514 PROCESS__NOATSECURE, NULL); 2515 } 2516 2517 return !!atsecure; 2518 } 2519 2520 static int match_file(const void *p, struct file *file, unsigned fd) 2521 { 2522 return file_has_perm(p, file, file_to_av(file)) ? fd + 1 : 0; 2523 } 2524 2525 /* Derived from fs/exec.c:flush_old_files. */ 2526 static inline void flush_unauthorized_files(const struct cred *cred, 2527 struct files_struct *files) 2528 { 2529 struct file *file, *devnull = NULL; 2530 struct tty_struct *tty; 2531 int drop_tty = 0; 2532 unsigned n; 2533 2534 tty = get_current_tty(); 2535 if (tty) { 2536 spin_lock(&tty->files_lock); 2537 if (!list_empty(&tty->tty_files)) { 2538 struct tty_file_private *file_priv; 2539 2540 /* Revalidate access to controlling tty. 2541 Use file_path_has_perm on the tty path directly 2542 rather than using file_has_perm, as this particular 2543 open file may belong to another process and we are 2544 only interested in the inode-based check here. */ 2545 file_priv = list_first_entry(&tty->tty_files, 2546 struct tty_file_private, list); 2547 file = file_priv->file; 2548 if (file_path_has_perm(cred, file, FILE__READ | FILE__WRITE)) 2549 drop_tty = 1; 2550 } 2551 spin_unlock(&tty->files_lock); 2552 tty_kref_put(tty); 2553 } 2554 /* Reset controlling tty. */ 2555 if (drop_tty) 2556 no_tty(); 2557 2558 /* Revalidate access to inherited open files. */ 2559 n = iterate_fd(files, 0, match_file, cred); 2560 if (!n) /* none found? */ 2561 return; 2562 2563 devnull = dentry_open(&selinux_null, O_RDWR, cred); 2564 if (IS_ERR(devnull)) 2565 devnull = NULL; 2566 /* replace all the matching ones with this */ 2567 do { 2568 replace_fd(n - 1, devnull, 0); 2569 } while ((n = iterate_fd(files, n, match_file, cred)) != 0); 2570 if (devnull) 2571 fput(devnull); 2572 } 2573 2574 /* 2575 * Prepare a process for imminent new credential changes due to exec 2576 */ 2577 static void selinux_bprm_committing_creds(struct linux_binprm *bprm) 2578 { 2579 struct task_security_struct *new_tsec; 2580 struct rlimit *rlim, *initrlim; 2581 int rc, i; 2582 2583 new_tsec = bprm->cred->security; 2584 if (new_tsec->sid == new_tsec->osid) 2585 return; 2586 2587 /* Close files for which the new task SID is not authorized. */ 2588 flush_unauthorized_files(bprm->cred, current->files); 2589 2590 /* Always clear parent death signal on SID transitions. */ 2591 current->pdeath_signal = 0; 2592 2593 /* Check whether the new SID can inherit resource limits from the old 2594 * SID. If not, reset all soft limits to the lower of the current 2595 * task's hard limit and the init task's soft limit. 2596 * 2597 * Note that the setting of hard limits (even to lower them) can be 2598 * controlled by the setrlimit check. The inclusion of the init task's 2599 * soft limit into the computation is to avoid resetting soft limits 2600 * higher than the default soft limit for cases where the default is 2601 * lower than the hard limit, e.g. RLIMIT_CORE or RLIMIT_STACK. 2602 */ 2603 rc = avc_has_perm(new_tsec->osid, new_tsec->sid, SECCLASS_PROCESS, 2604 PROCESS__RLIMITINH, NULL); 2605 if (rc) { 2606 /* protect against do_prlimit() */ 2607 task_lock(current); 2608 for (i = 0; i < RLIM_NLIMITS; i++) { 2609 rlim = current->signal->rlim + i; 2610 initrlim = init_task.signal->rlim + i; 2611 rlim->rlim_cur = min(rlim->rlim_max, initrlim->rlim_cur); 2612 } 2613 task_unlock(current); 2614 if (IS_ENABLED(CONFIG_POSIX_TIMERS)) 2615 update_rlimit_cpu(current, rlimit(RLIMIT_CPU)); 2616 } 2617 } 2618 2619 /* 2620 * Clean up the process immediately after the installation of new credentials 2621 * due to exec 2622 */ 2623 static void selinux_bprm_committed_creds(struct linux_binprm *bprm) 2624 { 2625 const struct task_security_struct *tsec = current_security(); 2626 struct itimerval itimer; 2627 u32 osid, sid; 2628 int rc, i; 2629 2630 osid = tsec->osid; 2631 sid = tsec->sid; 2632 2633 if (sid == osid) 2634 return; 2635 2636 /* Check whether the new SID can inherit signal state from the old SID. 2637 * If not, clear itimers to avoid subsequent signal generation and 2638 * flush and unblock signals. 2639 * 2640 * This must occur _after_ the task SID has been updated so that any 2641 * kill done after the flush will be checked against the new SID. 2642 */ 2643 rc = avc_has_perm(osid, sid, SECCLASS_PROCESS, PROCESS__SIGINH, NULL); 2644 if (rc) { 2645 if (IS_ENABLED(CONFIG_POSIX_TIMERS)) { 2646 memset(&itimer, 0, sizeof itimer); 2647 for (i = 0; i < 3; i++) 2648 do_setitimer(i, &itimer, NULL); 2649 } 2650 spin_lock_irq(¤t->sighand->siglock); 2651 if (!fatal_signal_pending(current)) { 2652 flush_sigqueue(¤t->pending); 2653 flush_sigqueue(¤t->signal->shared_pending); 2654 flush_signal_handlers(current, 1); 2655 sigemptyset(¤t->blocked); 2656 recalc_sigpending(); 2657 } 2658 spin_unlock_irq(¤t->sighand->siglock); 2659 } 2660 2661 /* Wake up the parent if it is waiting so that it can recheck 2662 * wait permission to the new task SID. */ 2663 read_lock(&tasklist_lock); 2664 __wake_up_parent(current, current->real_parent); 2665 read_unlock(&tasklist_lock); 2666 } 2667 2668 /* superblock security operations */ 2669 2670 static int selinux_sb_alloc_security(struct super_block *sb) 2671 { 2672 return superblock_alloc_security(sb); 2673 } 2674 2675 static void selinux_sb_free_security(struct super_block *sb) 2676 { 2677 superblock_free_security(sb); 2678 } 2679 2680 static inline int match_prefix(char *prefix, int plen, char *option, int olen) 2681 { 2682 if (plen > olen) 2683 return 0; 2684 2685 return !memcmp(prefix, option, plen); 2686 } 2687 2688 static inline int selinux_option(char *option, int len) 2689 { 2690 return (match_prefix(CONTEXT_STR, sizeof(CONTEXT_STR)-1, option, len) || 2691 match_prefix(FSCONTEXT_STR, sizeof(FSCONTEXT_STR)-1, option, len) || 2692 match_prefix(DEFCONTEXT_STR, sizeof(DEFCONTEXT_STR)-1, option, len) || 2693 match_prefix(ROOTCONTEXT_STR, sizeof(ROOTCONTEXT_STR)-1, option, len) || 2694 match_prefix(LABELSUPP_STR, sizeof(LABELSUPP_STR)-1, option, len)); 2695 } 2696 2697 static inline void take_option(char **to, char *from, int *first, int len) 2698 { 2699 if (!*first) { 2700 **to = ','; 2701 *to += 1; 2702 } else 2703 *first = 0; 2704 memcpy(*to, from, len); 2705 *to += len; 2706 } 2707 2708 static inline void take_selinux_option(char **to, char *from, int *first, 2709 int len) 2710 { 2711 int current_size = 0; 2712 2713 if (!*first) { 2714 **to = '|'; 2715 *to += 1; 2716 } else 2717 *first = 0; 2718 2719 while (current_size < len) { 2720 if (*from != '"') { 2721 **to = *from; 2722 *to += 1; 2723 } 2724 from += 1; 2725 current_size += 1; 2726 } 2727 } 2728 2729 static int selinux_sb_copy_data(char *orig, char *copy) 2730 { 2731 int fnosec, fsec, rc = 0; 2732 char *in_save, *in_curr, *in_end; 2733 char *sec_curr, *nosec_save, *nosec; 2734 int open_quote = 0; 2735 2736 in_curr = orig; 2737 sec_curr = copy; 2738 2739 nosec = (char *)get_zeroed_page(GFP_KERNEL); 2740 if (!nosec) { 2741 rc = -ENOMEM; 2742 goto out; 2743 } 2744 2745 nosec_save = nosec; 2746 fnosec = fsec = 1; 2747 in_save = in_end = orig; 2748 2749 do { 2750 if (*in_end == '"') 2751 open_quote = !open_quote; 2752 if ((*in_end == ',' && open_quote == 0) || 2753 *in_end == '\0') { 2754 int len = in_end - in_curr; 2755 2756 if (selinux_option(in_curr, len)) 2757 take_selinux_option(&sec_curr, in_curr, &fsec, len); 2758 else 2759 take_option(&nosec, in_curr, &fnosec, len); 2760 2761 in_curr = in_end + 1; 2762 } 2763 } while (*in_end++); 2764 2765 strcpy(in_save, nosec_save); 2766 free_page((unsigned long)nosec_save); 2767 out: 2768 return rc; 2769 } 2770 2771 static int selinux_sb_remount(struct super_block *sb, void *data) 2772 { 2773 int rc, i, *flags; 2774 struct security_mnt_opts opts; 2775 char *secdata, **mount_options; 2776 struct superblock_security_struct *sbsec = sb->s_security; 2777 2778 if (!(sbsec->flags & SE_SBINITIALIZED)) 2779 return 0; 2780 2781 if (!data) 2782 return 0; 2783 2784 if (sb->s_type->fs_flags & FS_BINARY_MOUNTDATA) 2785 return 0; 2786 2787 security_init_mnt_opts(&opts); 2788 secdata = alloc_secdata(); 2789 if (!secdata) 2790 return -ENOMEM; 2791 rc = selinux_sb_copy_data(data, secdata); 2792 if (rc) 2793 goto out_free_secdata; 2794 2795 rc = selinux_parse_opts_str(secdata, &opts); 2796 if (rc) 2797 goto out_free_secdata; 2798 2799 mount_options = opts.mnt_opts; 2800 flags = opts.mnt_opts_flags; 2801 2802 for (i = 0; i < opts.num_mnt_opts; i++) { 2803 u32 sid; 2804 2805 if (flags[i] == SBLABEL_MNT) 2806 continue; 2807 rc = security_context_str_to_sid(mount_options[i], &sid, GFP_KERNEL); 2808 if (rc) { 2809 printk(KERN_WARNING "SELinux: security_context_str_to_sid" 2810 "(%s) failed for (dev %s, type %s) errno=%d\n", 2811 mount_options[i], sb->s_id, sb->s_type->name, rc); 2812 goto out_free_opts; 2813 } 2814 rc = -EINVAL; 2815 switch (flags[i]) { 2816 case FSCONTEXT_MNT: 2817 if (bad_option(sbsec, FSCONTEXT_MNT, sbsec->sid, sid)) 2818 goto out_bad_option; 2819 break; 2820 case CONTEXT_MNT: 2821 if (bad_option(sbsec, CONTEXT_MNT, sbsec->mntpoint_sid, sid)) 2822 goto out_bad_option; 2823 break; 2824 case ROOTCONTEXT_MNT: { 2825 struct inode_security_struct *root_isec; 2826 root_isec = backing_inode_security(sb->s_root); 2827 2828 if (bad_option(sbsec, ROOTCONTEXT_MNT, root_isec->sid, sid)) 2829 goto out_bad_option; 2830 break; 2831 } 2832 case DEFCONTEXT_MNT: 2833 if (bad_option(sbsec, DEFCONTEXT_MNT, sbsec->def_sid, sid)) 2834 goto out_bad_option; 2835 break; 2836 default: 2837 goto out_free_opts; 2838 } 2839 } 2840 2841 rc = 0; 2842 out_free_opts: 2843 security_free_mnt_opts(&opts); 2844 out_free_secdata: 2845 free_secdata(secdata); 2846 return rc; 2847 out_bad_option: 2848 printk(KERN_WARNING "SELinux: unable to change security options " 2849 "during remount (dev %s, type=%s)\n", sb->s_id, 2850 sb->s_type->name); 2851 goto out_free_opts; 2852 } 2853 2854 static int selinux_sb_kern_mount(struct super_block *sb, int flags, void *data) 2855 { 2856 const struct cred *cred = current_cred(); 2857 struct common_audit_data ad; 2858 int rc; 2859 2860 rc = superblock_doinit(sb, data); 2861 if (rc) 2862 return rc; 2863 2864 /* Allow all mounts performed by the kernel */ 2865 if (flags & MS_KERNMOUNT) 2866 return 0; 2867 2868 ad.type = LSM_AUDIT_DATA_DENTRY; 2869 ad.u.dentry = sb->s_root; 2870 return superblock_has_perm(cred, sb, FILESYSTEM__MOUNT, &ad); 2871 } 2872 2873 static int selinux_sb_statfs(struct dentry *dentry) 2874 { 2875 const struct cred *cred = current_cred(); 2876 struct common_audit_data ad; 2877 2878 ad.type = LSM_AUDIT_DATA_DENTRY; 2879 ad.u.dentry = dentry->d_sb->s_root; 2880 return superblock_has_perm(cred, dentry->d_sb, FILESYSTEM__GETATTR, &ad); 2881 } 2882 2883 static int selinux_mount(const char *dev_name, 2884 const struct path *path, 2885 const char *type, 2886 unsigned long flags, 2887 void *data) 2888 { 2889 const struct cred *cred = current_cred(); 2890 2891 if (flags & MS_REMOUNT) 2892 return superblock_has_perm(cred, path->dentry->d_sb, 2893 FILESYSTEM__REMOUNT, NULL); 2894 else 2895 return path_has_perm(cred, path, FILE__MOUNTON); 2896 } 2897 2898 static int selinux_umount(struct vfsmount *mnt, int flags) 2899 { 2900 const struct cred *cred = current_cred(); 2901 2902 return superblock_has_perm(cred, mnt->mnt_sb, 2903 FILESYSTEM__UNMOUNT, NULL); 2904 } 2905 2906 /* inode security operations */ 2907 2908 static int selinux_inode_alloc_security(struct inode *inode) 2909 { 2910 return inode_alloc_security(inode); 2911 } 2912 2913 static void selinux_inode_free_security(struct inode *inode) 2914 { 2915 inode_free_security(inode); 2916 } 2917 2918 static int selinux_dentry_init_security(struct dentry *dentry, int mode, 2919 const struct qstr *name, void **ctx, 2920 u32 *ctxlen) 2921 { 2922 u32 newsid; 2923 int rc; 2924 2925 rc = selinux_determine_inode_label(current_security(), 2926 d_inode(dentry->d_parent), name, 2927 inode_mode_to_security_class(mode), 2928 &newsid); 2929 if (rc) 2930 return rc; 2931 2932 return security_sid_to_context(newsid, (char **)ctx, ctxlen); 2933 } 2934 2935 static int selinux_dentry_create_files_as(struct dentry *dentry, int mode, 2936 struct qstr *name, 2937 const struct cred *old, 2938 struct cred *new) 2939 { 2940 u32 newsid; 2941 int rc; 2942 struct task_security_struct *tsec; 2943 2944 rc = selinux_determine_inode_label(old->security, 2945 d_inode(dentry->d_parent), name, 2946 inode_mode_to_security_class(mode), 2947 &newsid); 2948 if (rc) 2949 return rc; 2950 2951 tsec = new->security; 2952 tsec->create_sid = newsid; 2953 return 0; 2954 } 2955 2956 static int selinux_inode_init_security(struct inode *inode, struct inode *dir, 2957 const struct qstr *qstr, 2958 const char **name, 2959 void **value, size_t *len) 2960 { 2961 const struct task_security_struct *tsec = current_security(); 2962 struct superblock_security_struct *sbsec; 2963 u32 sid, newsid, clen; 2964 int rc; 2965 char *context; 2966 2967 sbsec = dir->i_sb->s_security; 2968 2969 sid = tsec->sid; 2970 newsid = tsec->create_sid; 2971 2972 rc = selinux_determine_inode_label(current_security(), 2973 dir, qstr, 2974 inode_mode_to_security_class(inode->i_mode), 2975 &newsid); 2976 if (rc) 2977 return rc; 2978 2979 /* Possibly defer initialization to selinux_complete_init. */ 2980 if (sbsec->flags & SE_SBINITIALIZED) { 2981 struct inode_security_struct *isec = inode->i_security; 2982 isec->sclass = inode_mode_to_security_class(inode->i_mode); 2983 isec->sid = newsid; 2984 isec->initialized = LABEL_INITIALIZED; 2985 } 2986 2987 if (!ss_initialized || !(sbsec->flags & SBLABEL_MNT)) 2988 return -EOPNOTSUPP; 2989 2990 if (name) 2991 *name = XATTR_SELINUX_SUFFIX; 2992 2993 if (value && len) { 2994 rc = security_sid_to_context_force(newsid, &context, &clen); 2995 if (rc) 2996 return rc; 2997 *value = context; 2998 *len = clen; 2999 } 3000 3001 return 0; 3002 } 3003 3004 static int selinux_inode_create(struct inode *dir, struct dentry *dentry, umode_t mode) 3005 { 3006 return may_create(dir, dentry, SECCLASS_FILE); 3007 } 3008 3009 static int selinux_inode_link(struct dentry *old_dentry, struct inode *dir, struct dentry *new_dentry) 3010 { 3011 return may_link(dir, old_dentry, MAY_LINK); 3012 } 3013 3014 static int selinux_inode_unlink(struct inode *dir, struct dentry *dentry) 3015 { 3016 return may_link(dir, dentry, MAY_UNLINK); 3017 } 3018 3019 static int selinux_inode_symlink(struct inode *dir, struct dentry *dentry, const char *name) 3020 { 3021 return may_create(dir, dentry, SECCLASS_LNK_FILE); 3022 } 3023 3024 static int selinux_inode_mkdir(struct inode *dir, struct dentry *dentry, umode_t mask) 3025 { 3026 return may_create(dir, dentry, SECCLASS_DIR); 3027 } 3028 3029 static int selinux_inode_rmdir(struct inode *dir, struct dentry *dentry) 3030 { 3031 return may_link(dir, dentry, MAY_RMDIR); 3032 } 3033 3034 static int selinux_inode_mknod(struct inode *dir, struct dentry *dentry, umode_t mode, dev_t dev) 3035 { 3036 return may_create(dir, dentry, inode_mode_to_security_class(mode)); 3037 } 3038 3039 static int selinux_inode_rename(struct inode *old_inode, struct dentry *old_dentry, 3040 struct inode *new_inode, struct dentry *new_dentry) 3041 { 3042 return may_rename(old_inode, old_dentry, new_inode, new_dentry); 3043 } 3044 3045 static int selinux_inode_readlink(struct dentry *dentry) 3046 { 3047 const struct cred *cred = current_cred(); 3048 3049 return dentry_has_perm(cred, dentry, FILE__READ); 3050 } 3051 3052 static int selinux_inode_follow_link(struct dentry *dentry, struct inode *inode, 3053 bool rcu) 3054 { 3055 const struct cred *cred = current_cred(); 3056 struct common_audit_data ad; 3057 struct inode_security_struct *isec; 3058 u32 sid; 3059 3060 validate_creds(cred); 3061 3062 ad.type = LSM_AUDIT_DATA_DENTRY; 3063 ad.u.dentry = dentry; 3064 sid = cred_sid(cred); 3065 isec = inode_security_rcu(inode, rcu); 3066 if (IS_ERR(isec)) 3067 return PTR_ERR(isec); 3068 3069 return avc_has_perm_flags(sid, isec->sid, isec->sclass, FILE__READ, &ad, 3070 rcu ? MAY_NOT_BLOCK : 0); 3071 } 3072 3073 static noinline int audit_inode_permission(struct inode *inode, 3074 u32 perms, u32 audited, u32 denied, 3075 int result, 3076 unsigned flags) 3077 { 3078 struct common_audit_data ad; 3079 struct inode_security_struct *isec = inode->i_security; 3080 int rc; 3081 3082 ad.type = LSM_AUDIT_DATA_INODE; 3083 ad.u.inode = inode; 3084 3085 rc = slow_avc_audit(current_sid(), isec->sid, isec->sclass, perms, 3086 audited, denied, result, &ad, flags); 3087 if (rc) 3088 return rc; 3089 return 0; 3090 } 3091 3092 static int selinux_inode_permission(struct inode *inode, int mask) 3093 { 3094 const struct cred *cred = current_cred(); 3095 u32 perms; 3096 bool from_access; 3097 unsigned flags = mask & MAY_NOT_BLOCK; 3098 struct inode_security_struct *isec; 3099 u32 sid; 3100 struct av_decision avd; 3101 int rc, rc2; 3102 u32 audited, denied; 3103 3104 from_access = mask & MAY_ACCESS; 3105 mask &= (MAY_READ|MAY_WRITE|MAY_EXEC|MAY_APPEND); 3106 3107 /* No permission to check. Existence test. */ 3108 if (!mask) 3109 return 0; 3110 3111 validate_creds(cred); 3112 3113 if (unlikely(IS_PRIVATE(inode))) 3114 return 0; 3115 3116 perms = file_mask_to_av(inode->i_mode, mask); 3117 3118 sid = cred_sid(cred); 3119 isec = inode_security_rcu(inode, flags & MAY_NOT_BLOCK); 3120 if (IS_ERR(isec)) 3121 return PTR_ERR(isec); 3122 3123 rc = avc_has_perm_noaudit(sid, isec->sid, isec->sclass, perms, 0, &avd); 3124 audited = avc_audit_required(perms, &avd, rc, 3125 from_access ? FILE__AUDIT_ACCESS : 0, 3126 &denied); 3127 if (likely(!audited)) 3128 return rc; 3129 3130 rc2 = audit_inode_permission(inode, perms, audited, denied, rc, flags); 3131 if (rc2) 3132 return rc2; 3133 return rc; 3134 } 3135 3136 static int selinux_inode_setattr(struct dentry *dentry, struct iattr *iattr) 3137 { 3138 const struct cred *cred = current_cred(); 3139 unsigned int ia_valid = iattr->ia_valid; 3140 __u32 av = FILE__WRITE; 3141 3142 /* ATTR_FORCE is just used for ATTR_KILL_S[UG]ID. */ 3143 if (ia_valid & ATTR_FORCE) { 3144 ia_valid &= ~(ATTR_KILL_SUID | ATTR_KILL_SGID | ATTR_MODE | 3145 ATTR_FORCE); 3146 if (!ia_valid) 3147 return 0; 3148 } 3149 3150 if (ia_valid & (ATTR_MODE | ATTR_UID | ATTR_GID | 3151 ATTR_ATIME_SET | ATTR_MTIME_SET | ATTR_TIMES_SET)) 3152 return dentry_has_perm(cred, dentry, FILE__SETATTR); 3153 3154 if (selinux_policycap_openperm && (ia_valid & ATTR_SIZE) 3155 && !(ia_valid & ATTR_FILE)) 3156 av |= FILE__OPEN; 3157 3158 return dentry_has_perm(cred, dentry, av); 3159 } 3160 3161 static int selinux_inode_getattr(const struct path *path) 3162 { 3163 return path_has_perm(current_cred(), path, FILE__GETATTR); 3164 } 3165 3166 static int selinux_inode_setotherxattr(struct dentry *dentry, const char *name) 3167 { 3168 const struct cred *cred = current_cred(); 3169 3170 if (!strncmp(name, XATTR_SECURITY_PREFIX, 3171 sizeof XATTR_SECURITY_PREFIX - 1)) { 3172 if (!strcmp(name, XATTR_NAME_CAPS)) { 3173 if (!capable(CAP_SETFCAP)) 3174 return -EPERM; 3175 } else if (!capable(CAP_SYS_ADMIN)) { 3176 /* A different attribute in the security namespace. 3177 Restrict to administrator. */ 3178 return -EPERM; 3179 } 3180 } 3181 3182 /* Not an attribute we recognize, so just check the 3183 ordinary setattr permission. */ 3184 return dentry_has_perm(cred, dentry, FILE__SETATTR); 3185 } 3186 3187 static int selinux_inode_setxattr(struct dentry *dentry, const char *name, 3188 const void *value, size_t size, int flags) 3189 { 3190 struct inode *inode = d_backing_inode(dentry); 3191 struct inode_security_struct *isec; 3192 struct superblock_security_struct *sbsec; 3193 struct common_audit_data ad; 3194 u32 newsid, sid = current_sid(); 3195 int rc = 0; 3196 3197 if (strcmp(name, XATTR_NAME_SELINUX)) 3198 return selinux_inode_setotherxattr(dentry, name); 3199 3200 sbsec = inode->i_sb->s_security; 3201 if (!(sbsec->flags & SBLABEL_MNT)) 3202 return -EOPNOTSUPP; 3203 3204 if (!inode_owner_or_capable(inode)) 3205 return -EPERM; 3206 3207 ad.type = LSM_AUDIT_DATA_DENTRY; 3208 ad.u.dentry = dentry; 3209 3210 isec = backing_inode_security(dentry); 3211 rc = avc_has_perm(sid, isec->sid, isec->sclass, 3212 FILE__RELABELFROM, &ad); 3213 if (rc) 3214 return rc; 3215 3216 rc = security_context_to_sid(value, size, &newsid, GFP_KERNEL); 3217 if (rc == -EINVAL) { 3218 if (!capable(CAP_MAC_ADMIN)) { 3219 struct audit_buffer *ab; 3220 size_t audit_size; 3221 const char *str; 3222 3223 /* We strip a nul only if it is at the end, otherwise the 3224 * context contains a nul and we should audit that */ 3225 if (value) { 3226 str = value; 3227 if (str[size - 1] == '\0') 3228 audit_size = size - 1; 3229 else 3230 audit_size = size; 3231 } else { 3232 str = ""; 3233 audit_size = 0; 3234 } 3235 ab = audit_log_start(current->audit_context, GFP_ATOMIC, AUDIT_SELINUX_ERR); 3236 audit_log_format(ab, "op=setxattr invalid_context="); 3237 audit_log_n_untrustedstring(ab, value, audit_size); 3238 audit_log_end(ab); 3239 3240 return rc; 3241 } 3242 rc = security_context_to_sid_force(value, size, &newsid); 3243 } 3244 if (rc) 3245 return rc; 3246 3247 rc = avc_has_perm(sid, newsid, isec->sclass, 3248 FILE__RELABELTO, &ad); 3249 if (rc) 3250 return rc; 3251 3252 rc = security_validate_transition(isec->sid, newsid, sid, 3253 isec->sclass); 3254 if (rc) 3255 return rc; 3256 3257 return avc_has_perm(newsid, 3258 sbsec->sid, 3259 SECCLASS_FILESYSTEM, 3260 FILESYSTEM__ASSOCIATE, 3261 &ad); 3262 } 3263 3264 static void selinux_inode_post_setxattr(struct dentry *dentry, const char *name, 3265 const void *value, size_t size, 3266 int flags) 3267 { 3268 struct inode *inode = d_backing_inode(dentry); 3269 struct inode_security_struct *isec; 3270 u32 newsid; 3271 int rc; 3272 3273 if (strcmp(name, XATTR_NAME_SELINUX)) { 3274 /* Not an attribute we recognize, so nothing to do. */ 3275 return; 3276 } 3277 3278 rc = security_context_to_sid_force(value, size, &newsid); 3279 if (rc) { 3280 printk(KERN_ERR "SELinux: unable to map context to SID" 3281 "for (%s, %lu), rc=%d\n", 3282 inode->i_sb->s_id, inode->i_ino, -rc); 3283 return; 3284 } 3285 3286 isec = backing_inode_security(dentry); 3287 spin_lock(&isec->lock); 3288 isec->sclass = inode_mode_to_security_class(inode->i_mode); 3289 isec->sid = newsid; 3290 isec->initialized = LABEL_INITIALIZED; 3291 spin_unlock(&isec->lock); 3292 3293 return; 3294 } 3295 3296 static int selinux_inode_getxattr(struct dentry *dentry, const char *name) 3297 { 3298 const struct cred *cred = current_cred(); 3299 3300 return dentry_has_perm(cred, dentry, FILE__GETATTR); 3301 } 3302 3303 static int selinux_inode_listxattr(struct dentry *dentry) 3304 { 3305 const struct cred *cred = current_cred(); 3306 3307 return dentry_has_perm(cred, dentry, FILE__GETATTR); 3308 } 3309 3310 static int selinux_inode_removexattr(struct dentry *dentry, const char *name) 3311 { 3312 if (strcmp(name, XATTR_NAME_SELINUX)) 3313 return selinux_inode_setotherxattr(dentry, name); 3314 3315 /* No one is allowed to remove a SELinux security label. 3316 You can change the label, but all data must be labeled. */ 3317 return -EACCES; 3318 } 3319 3320 /* 3321 * Copy the inode security context value to the user. 3322 * 3323 * Permission check is handled by selinux_inode_getxattr hook. 3324 */ 3325 static int selinux_inode_getsecurity(struct inode *inode, const char *name, void **buffer, bool alloc) 3326 { 3327 u32 size; 3328 int error; 3329 char *context = NULL; 3330 struct inode_security_struct *isec; 3331 3332 if (strcmp(name, XATTR_SELINUX_SUFFIX)) 3333 return -EOPNOTSUPP; 3334 3335 /* 3336 * If the caller has CAP_MAC_ADMIN, then get the raw context 3337 * value even if it is not defined by current policy; otherwise, 3338 * use the in-core value under current policy. 3339 * Use the non-auditing forms of the permission checks since 3340 * getxattr may be called by unprivileged processes commonly 3341 * and lack of permission just means that we fall back to the 3342 * in-core context value, not a denial. 3343 */ 3344 error = cap_capable(current_cred(), &init_user_ns, CAP_MAC_ADMIN, 3345 SECURITY_CAP_NOAUDIT); 3346 if (!error) 3347 error = cred_has_capability(current_cred(), CAP_MAC_ADMIN, 3348 SECURITY_CAP_NOAUDIT, true); 3349 isec = inode_security(inode); 3350 if (!error) 3351 error = security_sid_to_context_force(isec->sid, &context, 3352 &size); 3353 else 3354 error = security_sid_to_context(isec->sid, &context, &size); 3355 if (error) 3356 return error; 3357 error = size; 3358 if (alloc) { 3359 *buffer = context; 3360 goto out_nofree; 3361 } 3362 kfree(context); 3363 out_nofree: 3364 return error; 3365 } 3366 3367 static int selinux_inode_setsecurity(struct inode *inode, const char *name, 3368 const void *value, size_t size, int flags) 3369 { 3370 struct inode_security_struct *isec = inode_security_novalidate(inode); 3371 u32 newsid; 3372 int rc; 3373 3374 if (strcmp(name, XATTR_SELINUX_SUFFIX)) 3375 return -EOPNOTSUPP; 3376 3377 if (!value || !size) 3378 return -EACCES; 3379 3380 rc = security_context_to_sid(value, size, &newsid, GFP_KERNEL); 3381 if (rc) 3382 return rc; 3383 3384 spin_lock(&isec->lock); 3385 isec->sclass = inode_mode_to_security_class(inode->i_mode); 3386 isec->sid = newsid; 3387 isec->initialized = LABEL_INITIALIZED; 3388 spin_unlock(&isec->lock); 3389 return 0; 3390 } 3391 3392 static int selinux_inode_listsecurity(struct inode *inode, char *buffer, size_t buffer_size) 3393 { 3394 const int len = sizeof(XATTR_NAME_SELINUX); 3395 if (buffer && len <= buffer_size) 3396 memcpy(buffer, XATTR_NAME_SELINUX, len); 3397 return len; 3398 } 3399 3400 static void selinux_inode_getsecid(struct inode *inode, u32 *secid) 3401 { 3402 struct inode_security_struct *isec = inode_security_novalidate(inode); 3403 *secid = isec->sid; 3404 } 3405 3406 static int selinux_inode_copy_up(struct dentry *src, struct cred **new) 3407 { 3408 u32 sid; 3409 struct task_security_struct *tsec; 3410 struct cred *new_creds = *new; 3411 3412 if (new_creds == NULL) { 3413 new_creds = prepare_creds(); 3414 if (!new_creds) 3415 return -ENOMEM; 3416 } 3417 3418 tsec = new_creds->security; 3419 /* Get label from overlay inode and set it in create_sid */ 3420 selinux_inode_getsecid(d_inode(src), &sid); 3421 tsec->create_sid = sid; 3422 *new = new_creds; 3423 return 0; 3424 } 3425 3426 static int selinux_inode_copy_up_xattr(const char *name) 3427 { 3428 /* The copy_up hook above sets the initial context on an inode, but we 3429 * don't then want to overwrite it by blindly copying all the lower 3430 * xattrs up. Instead, we have to filter out SELinux-related xattrs. 3431 */ 3432 if (strcmp(name, XATTR_NAME_SELINUX) == 0) 3433 return 1; /* Discard */ 3434 /* 3435 * Any other attribute apart from SELINUX is not claimed, supported 3436 * by selinux. 3437 */ 3438 return -EOPNOTSUPP; 3439 } 3440 3441 /* file security operations */ 3442 3443 static int selinux_revalidate_file_permission(struct file *file, int mask) 3444 { 3445 const struct cred *cred = current_cred(); 3446 struct inode *inode = file_inode(file); 3447 3448 /* file_mask_to_av won't add FILE__WRITE if MAY_APPEND is set */ 3449 if ((file->f_flags & O_APPEND) && (mask & MAY_WRITE)) 3450 mask |= MAY_APPEND; 3451 3452 return file_has_perm(cred, file, 3453 file_mask_to_av(inode->i_mode, mask)); 3454 } 3455 3456 static int selinux_file_permission(struct file *file, int mask) 3457 { 3458 struct inode *inode = file_inode(file); 3459 struct file_security_struct *fsec = file->f_security; 3460 struct inode_security_struct *isec; 3461 u32 sid = current_sid(); 3462 3463 if (!mask) 3464 /* No permission to check. Existence test. */ 3465 return 0; 3466 3467 isec = inode_security(inode); 3468 if (sid == fsec->sid && fsec->isid == isec->sid && 3469 fsec->pseqno == avc_policy_seqno()) 3470 /* No change since file_open check. */ 3471 return 0; 3472 3473 return selinux_revalidate_file_permission(file, mask); 3474 } 3475 3476 static int selinux_file_alloc_security(struct file *file) 3477 { 3478 return file_alloc_security(file); 3479 } 3480 3481 static void selinux_file_free_security(struct file *file) 3482 { 3483 file_free_security(file); 3484 } 3485 3486 /* 3487 * Check whether a task has the ioctl permission and cmd 3488 * operation to an inode. 3489 */ 3490 static int ioctl_has_perm(const struct cred *cred, struct file *file, 3491 u32 requested, u16 cmd) 3492 { 3493 struct common_audit_data ad; 3494 struct file_security_struct *fsec = file->f_security; 3495 struct inode *inode = file_inode(file); 3496 struct inode_security_struct *isec; 3497 struct lsm_ioctlop_audit ioctl; 3498 u32 ssid = cred_sid(cred); 3499 int rc; 3500 u8 driver = cmd >> 8; 3501 u8 xperm = cmd & 0xff; 3502 3503 ad.type = LSM_AUDIT_DATA_IOCTL_OP; 3504 ad.u.op = &ioctl; 3505 ad.u.op->cmd = cmd; 3506 ad.u.op->path = file->f_path; 3507 3508 if (ssid != fsec->sid) { 3509 rc = avc_has_perm(ssid, fsec->sid, 3510 SECCLASS_FD, 3511 FD__USE, 3512 &ad); 3513 if (rc) 3514 goto out; 3515 } 3516 3517 if (unlikely(IS_PRIVATE(inode))) 3518 return 0; 3519 3520 isec = inode_security(inode); 3521 rc = avc_has_extended_perms(ssid, isec->sid, isec->sclass, 3522 requested, driver, xperm, &ad); 3523 out: 3524 return rc; 3525 } 3526 3527 static int selinux_file_ioctl(struct file *file, unsigned int cmd, 3528 unsigned long arg) 3529 { 3530 const struct cred *cred = current_cred(); 3531 int error = 0; 3532 3533 switch (cmd) { 3534 case FIONREAD: 3535 /* fall through */ 3536 case FIBMAP: 3537 /* fall through */ 3538 case FIGETBSZ: 3539 /* fall through */ 3540 case FS_IOC_GETFLAGS: 3541 /* fall through */ 3542 case FS_IOC_GETVERSION: 3543 error = file_has_perm(cred, file, FILE__GETATTR); 3544 break; 3545 3546 case FS_IOC_SETFLAGS: 3547 /* fall through */ 3548 case FS_IOC_SETVERSION: 3549 error = file_has_perm(cred, file, FILE__SETATTR); 3550 break; 3551 3552 /* sys_ioctl() checks */ 3553 case FIONBIO: 3554 /* fall through */ 3555 case FIOASYNC: 3556 error = file_has_perm(cred, file, 0); 3557 break; 3558 3559 case KDSKBENT: 3560 case KDSKBSENT: 3561 error = cred_has_capability(cred, CAP_SYS_TTY_CONFIG, 3562 SECURITY_CAP_AUDIT, true); 3563 break; 3564 3565 /* default case assumes that the command will go 3566 * to the file's ioctl() function. 3567 */ 3568 default: 3569 error = ioctl_has_perm(cred, file, FILE__IOCTL, (u16) cmd); 3570 } 3571 return error; 3572 } 3573 3574 static int default_noexec; 3575 3576 static int file_map_prot_check(struct file *file, unsigned long prot, int shared) 3577 { 3578 const struct cred *cred = current_cred(); 3579 int rc = 0; 3580 3581 if (default_noexec && 3582 (prot & PROT_EXEC) && (!file || IS_PRIVATE(file_inode(file)) || 3583 (!shared && (prot & PROT_WRITE)))) { 3584 /* 3585 * We are making executable an anonymous mapping or a 3586 * private file mapping that will also be writable. 3587 * This has an additional check. 3588 */ 3589 rc = cred_has_perm(cred, cred, PROCESS__EXECMEM); 3590 if (rc) 3591 goto error; 3592 } 3593 3594 if (file) { 3595 /* read access is always possible with a mapping */ 3596 u32 av = FILE__READ; 3597 3598 /* write access only matters if the mapping is shared */ 3599 if (shared && (prot & PROT_WRITE)) 3600 av |= FILE__WRITE; 3601 3602 if (prot & PROT_EXEC) 3603 av |= FILE__EXECUTE; 3604 3605 return file_has_perm(cred, file, av); 3606 } 3607 3608 error: 3609 return rc; 3610 } 3611 3612 static int selinux_mmap_addr(unsigned long addr) 3613 { 3614 int rc = 0; 3615 3616 if (addr < CONFIG_LSM_MMAP_MIN_ADDR) { 3617 u32 sid = current_sid(); 3618 rc = avc_has_perm(sid, sid, SECCLASS_MEMPROTECT, 3619 MEMPROTECT__MMAP_ZERO, NULL); 3620 } 3621 3622 return rc; 3623 } 3624 3625 static int selinux_mmap_file(struct file *file, unsigned long reqprot, 3626 unsigned long prot, unsigned long flags) 3627 { 3628 if (selinux_checkreqprot) 3629 prot = reqprot; 3630 3631 return file_map_prot_check(file, prot, 3632 (flags & MAP_TYPE) == MAP_SHARED); 3633 } 3634 3635 static int selinux_file_mprotect(struct vm_area_struct *vma, 3636 unsigned long reqprot, 3637 unsigned long prot) 3638 { 3639 const struct cred *cred = current_cred(); 3640 3641 if (selinux_checkreqprot) 3642 prot = reqprot; 3643 3644 if (default_noexec && 3645 (prot & PROT_EXEC) && !(vma->vm_flags & VM_EXEC)) { 3646 int rc = 0; 3647 if (vma->vm_start >= vma->vm_mm->start_brk && 3648 vma->vm_end <= vma->vm_mm->brk) { 3649 rc = cred_has_perm(cred, cred, PROCESS__EXECHEAP); 3650 } else if (!vma->vm_file && 3651 ((vma->vm_start <= vma->vm_mm->start_stack && 3652 vma->vm_end >= vma->vm_mm->start_stack) || 3653 vma_is_stack_for_current(vma))) { 3654 rc = current_has_perm(current, PROCESS__EXECSTACK); 3655 } else if (vma->vm_file && vma->anon_vma) { 3656 /* 3657 * We are making executable a file mapping that has 3658 * had some COW done. Since pages might have been 3659 * written, check ability to execute the possibly 3660 * modified content. This typically should only 3661 * occur for text relocations. 3662 */ 3663 rc = file_has_perm(cred, vma->vm_file, FILE__EXECMOD); 3664 } 3665 if (rc) 3666 return rc; 3667 } 3668 3669 return file_map_prot_check(vma->vm_file, prot, vma->vm_flags&VM_SHARED); 3670 } 3671 3672 static int selinux_file_lock(struct file *file, unsigned int cmd) 3673 { 3674 const struct cred *cred = current_cred(); 3675 3676 return file_has_perm(cred, file, FILE__LOCK); 3677 } 3678 3679 static int selinux_file_fcntl(struct file *file, unsigned int cmd, 3680 unsigned long arg) 3681 { 3682 const struct cred *cred = current_cred(); 3683 int err = 0; 3684 3685 switch (cmd) { 3686 case F_SETFL: 3687 if ((file->f_flags & O_APPEND) && !(arg & O_APPEND)) { 3688 err = file_has_perm(cred, file, FILE__WRITE); 3689 break; 3690 } 3691 /* fall through */ 3692 case F_SETOWN: 3693 case F_SETSIG: 3694 case F_GETFL: 3695 case F_GETOWN: 3696 case F_GETSIG: 3697 case F_GETOWNER_UIDS: 3698 /* Just check FD__USE permission */ 3699 err = file_has_perm(cred, file, 0); 3700 break; 3701 case F_GETLK: 3702 case F_SETLK: 3703 case F_SETLKW: 3704 case F_OFD_GETLK: 3705 case F_OFD_SETLK: 3706 case F_OFD_SETLKW: 3707 #if BITS_PER_LONG == 32 3708 case F_GETLK64: 3709 case F_SETLK64: 3710 case F_SETLKW64: 3711 #endif 3712 err = file_has_perm(cred, file, FILE__LOCK); 3713 break; 3714 } 3715 3716 return err; 3717 } 3718 3719 static void selinux_file_set_fowner(struct file *file) 3720 { 3721 struct file_security_struct *fsec; 3722 3723 fsec = file->f_security; 3724 fsec->fown_sid = current_sid(); 3725 } 3726 3727 static int selinux_file_send_sigiotask(struct task_struct *tsk, 3728 struct fown_struct *fown, int signum) 3729 { 3730 struct file *file; 3731 u32 sid = task_sid(tsk); 3732 u32 perm; 3733 struct file_security_struct *fsec; 3734 3735 /* struct fown_struct is never outside the context of a struct file */ 3736 file = container_of(fown, struct file, f_owner); 3737 3738 fsec = file->f_security; 3739 3740 if (!signum) 3741 perm = signal_to_av(SIGIO); /* as per send_sigio_to_task */ 3742 else 3743 perm = signal_to_av(signum); 3744 3745 return avc_has_perm(fsec->fown_sid, sid, 3746 SECCLASS_PROCESS, perm, NULL); 3747 } 3748 3749 static int selinux_file_receive(struct file *file) 3750 { 3751 const struct cred *cred = current_cred(); 3752 3753 return file_has_perm(cred, file, file_to_av(file)); 3754 } 3755 3756 static int selinux_file_open(struct file *file, const struct cred *cred) 3757 { 3758 struct file_security_struct *fsec; 3759 struct inode_security_struct *isec; 3760 3761 fsec = file->f_security; 3762 isec = inode_security(file_inode(file)); 3763 /* 3764 * Save inode label and policy sequence number 3765 * at open-time so that selinux_file_permission 3766 * can determine whether revalidation is necessary. 3767 * Task label is already saved in the file security 3768 * struct as its SID. 3769 */ 3770 fsec->isid = isec->sid; 3771 fsec->pseqno = avc_policy_seqno(); 3772 /* 3773 * Since the inode label or policy seqno may have changed 3774 * between the selinux_inode_permission check and the saving 3775 * of state above, recheck that access is still permitted. 3776 * Otherwise, access might never be revalidated against the 3777 * new inode label or new policy. 3778 * This check is not redundant - do not remove. 3779 */ 3780 return file_path_has_perm(cred, file, open_file_to_av(file)); 3781 } 3782 3783 /* task security operations */ 3784 3785 static int selinux_task_create(unsigned long clone_flags) 3786 { 3787 return current_has_perm(current, PROCESS__FORK); 3788 } 3789 3790 /* 3791 * allocate the SELinux part of blank credentials 3792 */ 3793 static int selinux_cred_alloc_blank(struct cred *cred, gfp_t gfp) 3794 { 3795 struct task_security_struct *tsec; 3796 3797 tsec = kzalloc(sizeof(struct task_security_struct), gfp); 3798 if (!tsec) 3799 return -ENOMEM; 3800 3801 cred->security = tsec; 3802 return 0; 3803 } 3804 3805 /* 3806 * detach and free the LSM part of a set of credentials 3807 */ 3808 static void selinux_cred_free(struct cred *cred) 3809 { 3810 struct task_security_struct *tsec = cred->security; 3811 3812 /* 3813 * cred->security == NULL if security_cred_alloc_blank() or 3814 * security_prepare_creds() returned an error. 3815 */ 3816 BUG_ON(cred->security && (unsigned long) cred->security < PAGE_SIZE); 3817 cred->security = (void *) 0x7UL; 3818 kfree(tsec); 3819 } 3820 3821 /* 3822 * prepare a new set of credentials for modification 3823 */ 3824 static int selinux_cred_prepare(struct cred *new, const struct cred *old, 3825 gfp_t gfp) 3826 { 3827 const struct task_security_struct *old_tsec; 3828 struct task_security_struct *tsec; 3829 3830 old_tsec = old->security; 3831 3832 tsec = kmemdup(old_tsec, sizeof(struct task_security_struct), gfp); 3833 if (!tsec) 3834 return -ENOMEM; 3835 3836 new->security = tsec; 3837 return 0; 3838 } 3839 3840 /* 3841 * transfer the SELinux data to a blank set of creds 3842 */ 3843 static void selinux_cred_transfer(struct cred *new, const struct cred *old) 3844 { 3845 const struct task_security_struct *old_tsec = old->security; 3846 struct task_security_struct *tsec = new->security; 3847 3848 *tsec = *old_tsec; 3849 } 3850 3851 /* 3852 * set the security data for a kernel service 3853 * - all the creation contexts are set to unlabelled 3854 */ 3855 static int selinux_kernel_act_as(struct cred *new, u32 secid) 3856 { 3857 struct task_security_struct *tsec = new->security; 3858 u32 sid = current_sid(); 3859 int ret; 3860 3861 ret = avc_has_perm(sid, secid, 3862 SECCLASS_KERNEL_SERVICE, 3863 KERNEL_SERVICE__USE_AS_OVERRIDE, 3864 NULL); 3865 if (ret == 0) { 3866 tsec->sid = secid; 3867 tsec->create_sid = 0; 3868 tsec->keycreate_sid = 0; 3869 tsec->sockcreate_sid = 0; 3870 } 3871 return ret; 3872 } 3873 3874 /* 3875 * set the file creation context in a security record to the same as the 3876 * objective context of the specified inode 3877 */ 3878 static int selinux_kernel_create_files_as(struct cred *new, struct inode *inode) 3879 { 3880 struct inode_security_struct *isec = inode_security(inode); 3881 struct task_security_struct *tsec = new->security; 3882 u32 sid = current_sid(); 3883 int ret; 3884 3885 ret = avc_has_perm(sid, isec->sid, 3886 SECCLASS_KERNEL_SERVICE, 3887 KERNEL_SERVICE__CREATE_FILES_AS, 3888 NULL); 3889 3890 if (ret == 0) 3891 tsec->create_sid = isec->sid; 3892 return ret; 3893 } 3894 3895 static int selinux_kernel_module_request(char *kmod_name) 3896 { 3897 u32 sid; 3898 struct common_audit_data ad; 3899 3900 sid = task_sid(current); 3901 3902 ad.type = LSM_AUDIT_DATA_KMOD; 3903 ad.u.kmod_name = kmod_name; 3904 3905 return avc_has_perm(sid, SECINITSID_KERNEL, SECCLASS_SYSTEM, 3906 SYSTEM__MODULE_REQUEST, &ad); 3907 } 3908 3909 static int selinux_kernel_module_from_file(struct file *file) 3910 { 3911 struct common_audit_data ad; 3912 struct inode_security_struct *isec; 3913 struct file_security_struct *fsec; 3914 u32 sid = current_sid(); 3915 int rc; 3916 3917 /* init_module */ 3918 if (file == NULL) 3919 return avc_has_perm(sid, sid, SECCLASS_SYSTEM, 3920 SYSTEM__MODULE_LOAD, NULL); 3921 3922 /* finit_module */ 3923 3924 ad.type = LSM_AUDIT_DATA_FILE; 3925 ad.u.file = file; 3926 3927 fsec = file->f_security; 3928 if (sid != fsec->sid) { 3929 rc = avc_has_perm(sid, fsec->sid, SECCLASS_FD, FD__USE, &ad); 3930 if (rc) 3931 return rc; 3932 } 3933 3934 isec = inode_security(file_inode(file)); 3935 return avc_has_perm(sid, isec->sid, SECCLASS_SYSTEM, 3936 SYSTEM__MODULE_LOAD, &ad); 3937 } 3938 3939 static int selinux_kernel_read_file(struct file *file, 3940 enum kernel_read_file_id id) 3941 { 3942 int rc = 0; 3943 3944 switch (id) { 3945 case READING_MODULE: 3946 rc = selinux_kernel_module_from_file(file); 3947 break; 3948 default: 3949 break; 3950 } 3951 3952 return rc; 3953 } 3954 3955 static int selinux_task_setpgid(struct task_struct *p, pid_t pgid) 3956 { 3957 return current_has_perm(p, PROCESS__SETPGID); 3958 } 3959 3960 static int selinux_task_getpgid(struct task_struct *p) 3961 { 3962 return current_has_perm(p, PROCESS__GETPGID); 3963 } 3964 3965 static int selinux_task_getsid(struct task_struct *p) 3966 { 3967 return current_has_perm(p, PROCESS__GETSESSION); 3968 } 3969 3970 static void selinux_task_getsecid(struct task_struct *p, u32 *secid) 3971 { 3972 *secid = task_sid(p); 3973 } 3974 3975 static int selinux_task_setnice(struct task_struct *p, int nice) 3976 { 3977 return current_has_perm(p, PROCESS__SETSCHED); 3978 } 3979 3980 static int selinux_task_setioprio(struct task_struct *p, int ioprio) 3981 { 3982 return current_has_perm(p, PROCESS__SETSCHED); 3983 } 3984 3985 static int selinux_task_getioprio(struct task_struct *p) 3986 { 3987 return current_has_perm(p, PROCESS__GETSCHED); 3988 } 3989 3990 static int selinux_task_setrlimit(struct task_struct *p, unsigned int resource, 3991 struct rlimit *new_rlim) 3992 { 3993 struct rlimit *old_rlim = p->signal->rlim + resource; 3994 3995 /* Control the ability to change the hard limit (whether 3996 lowering or raising it), so that the hard limit can 3997 later be used as a safe reset point for the soft limit 3998 upon context transitions. See selinux_bprm_committing_creds. */ 3999 if (old_rlim->rlim_max != new_rlim->rlim_max) 4000 return current_has_perm(p, PROCESS__SETRLIMIT); 4001 4002 return 0; 4003 } 4004 4005 static int selinux_task_setscheduler(struct task_struct *p) 4006 { 4007 return current_has_perm(p, PROCESS__SETSCHED); 4008 } 4009 4010 static int selinux_task_getscheduler(struct task_struct *p) 4011 { 4012 return current_has_perm(p, PROCESS__GETSCHED); 4013 } 4014 4015 static int selinux_task_movememory(struct task_struct *p) 4016 { 4017 return current_has_perm(p, PROCESS__SETSCHED); 4018 } 4019 4020 static int selinux_task_kill(struct task_struct *p, struct siginfo *info, 4021 int sig, u32 secid) 4022 { 4023 u32 perm; 4024 int rc; 4025 4026 if (!sig) 4027 perm = PROCESS__SIGNULL; /* null signal; existence test */ 4028 else 4029 perm = signal_to_av(sig); 4030 if (secid) 4031 rc = avc_has_perm(secid, task_sid(p), 4032 SECCLASS_PROCESS, perm, NULL); 4033 else 4034 rc = current_has_perm(p, perm); 4035 return rc; 4036 } 4037 4038 static int selinux_task_wait(struct task_struct *p) 4039 { 4040 return task_has_perm(p, current, PROCESS__SIGCHLD); 4041 } 4042 4043 static void selinux_task_to_inode(struct task_struct *p, 4044 struct inode *inode) 4045 { 4046 struct inode_security_struct *isec = inode->i_security; 4047 u32 sid = task_sid(p); 4048 4049 spin_lock(&isec->lock); 4050 isec->sclass = inode_mode_to_security_class(inode->i_mode); 4051 isec->sid = sid; 4052 isec->initialized = LABEL_INITIALIZED; 4053 spin_unlock(&isec->lock); 4054 } 4055 4056 /* Returns error only if unable to parse addresses */ 4057 static int selinux_parse_skb_ipv4(struct sk_buff *skb, 4058 struct common_audit_data *ad, u8 *proto) 4059 { 4060 int offset, ihlen, ret = -EINVAL; 4061 struct iphdr _iph, *ih; 4062 4063 offset = skb_network_offset(skb); 4064 ih = skb_header_pointer(skb, offset, sizeof(_iph), &_iph); 4065 if (ih == NULL) 4066 goto out; 4067 4068 ihlen = ih->ihl * 4; 4069 if (ihlen < sizeof(_iph)) 4070 goto out; 4071 4072 ad->u.net->v4info.saddr = ih->saddr; 4073 ad->u.net->v4info.daddr = ih->daddr; 4074 ret = 0; 4075 4076 if (proto) 4077 *proto = ih->protocol; 4078 4079 switch (ih->protocol) { 4080 case IPPROTO_TCP: { 4081 struct tcphdr _tcph, *th; 4082 4083 if (ntohs(ih->frag_off) & IP_OFFSET) 4084 break; 4085 4086 offset += ihlen; 4087 th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph); 4088 if (th == NULL) 4089 break; 4090 4091 ad->u.net->sport = th->source; 4092 ad->u.net->dport = th->dest; 4093 break; 4094 } 4095 4096 case IPPROTO_UDP: { 4097 struct udphdr _udph, *uh; 4098 4099 if (ntohs(ih->frag_off) & IP_OFFSET) 4100 break; 4101 4102 offset += ihlen; 4103 uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph); 4104 if (uh == NULL) 4105 break; 4106 4107 ad->u.net->sport = uh->source; 4108 ad->u.net->dport = uh->dest; 4109 break; 4110 } 4111 4112 case IPPROTO_DCCP: { 4113 struct dccp_hdr _dccph, *dh; 4114 4115 if (ntohs(ih->frag_off) & IP_OFFSET) 4116 break; 4117 4118 offset += ihlen; 4119 dh = skb_header_pointer(skb, offset, sizeof(_dccph), &_dccph); 4120 if (dh == NULL) 4121 break; 4122 4123 ad->u.net->sport = dh->dccph_sport; 4124 ad->u.net->dport = dh->dccph_dport; 4125 break; 4126 } 4127 4128 default: 4129 break; 4130 } 4131 out: 4132 return ret; 4133 } 4134 4135 #if IS_ENABLED(CONFIG_IPV6) 4136 4137 /* Returns error only if unable to parse addresses */ 4138 static int selinux_parse_skb_ipv6(struct sk_buff *skb, 4139 struct common_audit_data *ad, u8 *proto) 4140 { 4141 u8 nexthdr; 4142 int ret = -EINVAL, offset; 4143 struct ipv6hdr _ipv6h, *ip6; 4144 __be16 frag_off; 4145 4146 offset = skb_network_offset(skb); 4147 ip6 = skb_header_pointer(skb, offset, sizeof(_ipv6h), &_ipv6h); 4148 if (ip6 == NULL) 4149 goto out; 4150 4151 ad->u.net->v6info.saddr = ip6->saddr; 4152 ad->u.net->v6info.daddr = ip6->daddr; 4153 ret = 0; 4154 4155 nexthdr = ip6->nexthdr; 4156 offset += sizeof(_ipv6h); 4157 offset = ipv6_skip_exthdr(skb, offset, &nexthdr, &frag_off); 4158 if (offset < 0) 4159 goto out; 4160 4161 if (proto) 4162 *proto = nexthdr; 4163 4164 switch (nexthdr) { 4165 case IPPROTO_TCP: { 4166 struct tcphdr _tcph, *th; 4167 4168 th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph); 4169 if (th == NULL) 4170 break; 4171 4172 ad->u.net->sport = th->source; 4173 ad->u.net->dport = th->dest; 4174 break; 4175 } 4176 4177 case IPPROTO_UDP: { 4178 struct udphdr _udph, *uh; 4179 4180 uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph); 4181 if (uh == NULL) 4182 break; 4183 4184 ad->u.net->sport = uh->source; 4185 ad->u.net->dport = uh->dest; 4186 break; 4187 } 4188 4189 case IPPROTO_DCCP: { 4190 struct dccp_hdr _dccph, *dh; 4191 4192 dh = skb_header_pointer(skb, offset, sizeof(_dccph), &_dccph); 4193 if (dh == NULL) 4194 break; 4195 4196 ad->u.net->sport = dh->dccph_sport; 4197 ad->u.net->dport = dh->dccph_dport; 4198 break; 4199 } 4200 4201 /* includes fragments */ 4202 default: 4203 break; 4204 } 4205 out: 4206 return ret; 4207 } 4208 4209 #endif /* IPV6 */ 4210 4211 static int selinux_parse_skb(struct sk_buff *skb, struct common_audit_data *ad, 4212 char **_addrp, int src, u8 *proto) 4213 { 4214 char *addrp; 4215 int ret; 4216 4217 switch (ad->u.net->family) { 4218 case PF_INET: 4219 ret = selinux_parse_skb_ipv4(skb, ad, proto); 4220 if (ret) 4221 goto parse_error; 4222 addrp = (char *)(src ? &ad->u.net->v4info.saddr : 4223 &ad->u.net->v4info.daddr); 4224 goto okay; 4225 4226 #if IS_ENABLED(CONFIG_IPV6) 4227 case PF_INET6: 4228 ret = selinux_parse_skb_ipv6(skb, ad, proto); 4229 if (ret) 4230 goto parse_error; 4231 addrp = (char *)(src ? &ad->u.net->v6info.saddr : 4232 &ad->u.net->v6info.daddr); 4233 goto okay; 4234 #endif /* IPV6 */ 4235 default: 4236 addrp = NULL; 4237 goto okay; 4238 } 4239 4240 parse_error: 4241 printk(KERN_WARNING 4242 "SELinux: failure in selinux_parse_skb()," 4243 " unable to parse packet\n"); 4244 return ret; 4245 4246 okay: 4247 if (_addrp) 4248 *_addrp = addrp; 4249 return 0; 4250 } 4251 4252 /** 4253 * selinux_skb_peerlbl_sid - Determine the peer label of a packet 4254 * @skb: the packet 4255 * @family: protocol family 4256 * @sid: the packet's peer label SID 4257 * 4258 * Description: 4259 * Check the various different forms of network peer labeling and determine 4260 * the peer label/SID for the packet; most of the magic actually occurs in 4261 * the security server function security_net_peersid_cmp(). The function 4262 * returns zero if the value in @sid is valid (although it may be SECSID_NULL) 4263 * or -EACCES if @sid is invalid due to inconsistencies with the different 4264 * peer labels. 4265 * 4266 */ 4267 static int selinux_skb_peerlbl_sid(struct sk_buff *skb, u16 family, u32 *sid) 4268 { 4269 int err; 4270 u32 xfrm_sid; 4271 u32 nlbl_sid; 4272 u32 nlbl_type; 4273 4274 err = selinux_xfrm_skb_sid(skb, &xfrm_sid); 4275 if (unlikely(err)) 4276 return -EACCES; 4277 err = selinux_netlbl_skbuff_getsid(skb, family, &nlbl_type, &nlbl_sid); 4278 if (unlikely(err)) 4279 return -EACCES; 4280 4281 err = security_net_peersid_resolve(nlbl_sid, nlbl_type, xfrm_sid, sid); 4282 if (unlikely(err)) { 4283 printk(KERN_WARNING 4284 "SELinux: failure in selinux_skb_peerlbl_sid()," 4285 " unable to determine packet's peer label\n"); 4286 return -EACCES; 4287 } 4288 4289 return 0; 4290 } 4291 4292 /** 4293 * selinux_conn_sid - Determine the child socket label for a connection 4294 * @sk_sid: the parent socket's SID 4295 * @skb_sid: the packet's SID 4296 * @conn_sid: the resulting connection SID 4297 * 4298 * If @skb_sid is valid then the user:role:type information from @sk_sid is 4299 * combined with the MLS information from @skb_sid in order to create 4300 * @conn_sid. If @skb_sid is not valid then then @conn_sid is simply a copy 4301 * of @sk_sid. Returns zero on success, negative values on failure. 4302 * 4303 */ 4304 static int selinux_conn_sid(u32 sk_sid, u32 skb_sid, u32 *conn_sid) 4305 { 4306 int err = 0; 4307 4308 if (skb_sid != SECSID_NULL) 4309 err = security_sid_mls_copy(sk_sid, skb_sid, conn_sid); 4310 else 4311 *conn_sid = sk_sid; 4312 4313 return err; 4314 } 4315 4316 /* socket security operations */ 4317 4318 static int socket_sockcreate_sid(const struct task_security_struct *tsec, 4319 u16 secclass, u32 *socksid) 4320 { 4321 if (tsec->sockcreate_sid > SECSID_NULL) { 4322 *socksid = tsec->sockcreate_sid; 4323 return 0; 4324 } 4325 4326 return security_transition_sid(tsec->sid, tsec->sid, secclass, NULL, 4327 socksid); 4328 } 4329 4330 static int sock_has_perm(struct task_struct *task, struct sock *sk, u32 perms) 4331 { 4332 struct sk_security_struct *sksec = sk->sk_security; 4333 struct common_audit_data ad; 4334 struct lsm_network_audit net = {0,}; 4335 u32 tsid = task_sid(task); 4336 4337 if (sksec->sid == SECINITSID_KERNEL) 4338 return 0; 4339 4340 ad.type = LSM_AUDIT_DATA_NET; 4341 ad.u.net = &net; 4342 ad.u.net->sk = sk; 4343 4344 return avc_has_perm(tsid, sksec->sid, sksec->sclass, perms, &ad); 4345 } 4346 4347 static int selinux_socket_create(int family, int type, 4348 int protocol, int kern) 4349 { 4350 const struct task_security_struct *tsec = current_security(); 4351 u32 newsid; 4352 u16 secclass; 4353 int rc; 4354 4355 if (kern) 4356 return 0; 4357 4358 secclass = socket_type_to_security_class(family, type, protocol); 4359 rc = socket_sockcreate_sid(tsec, secclass, &newsid); 4360 if (rc) 4361 return rc; 4362 4363 return avc_has_perm(tsec->sid, newsid, secclass, SOCKET__CREATE, NULL); 4364 } 4365 4366 static int selinux_socket_post_create(struct socket *sock, int family, 4367 int type, int protocol, int kern) 4368 { 4369 const struct task_security_struct *tsec = current_security(); 4370 struct inode_security_struct *isec = inode_security_novalidate(SOCK_INODE(sock)); 4371 struct sk_security_struct *sksec; 4372 u16 sclass = socket_type_to_security_class(family, type, protocol); 4373 u32 sid = SECINITSID_KERNEL; 4374 int err = 0; 4375 4376 if (!kern) { 4377 err = socket_sockcreate_sid(tsec, sclass, &sid); 4378 if (err) 4379 return err; 4380 } 4381 4382 isec->sclass = sclass; 4383 isec->sid = sid; 4384 isec->initialized = LABEL_INITIALIZED; 4385 4386 if (sock->sk) { 4387 sksec = sock->sk->sk_security; 4388 sksec->sclass = sclass; 4389 sksec->sid = sid; 4390 err = selinux_netlbl_socket_post_create(sock->sk, family); 4391 } 4392 4393 return err; 4394 } 4395 4396 /* Range of port numbers used to automatically bind. 4397 Need to determine whether we should perform a name_bind 4398 permission check between the socket and the port number. */ 4399 4400 static int selinux_socket_bind(struct socket *sock, struct sockaddr *address, int addrlen) 4401 { 4402 struct sock *sk = sock->sk; 4403 u16 family; 4404 int err; 4405 4406 err = sock_has_perm(current, sk, SOCKET__BIND); 4407 if (err) 4408 goto out; 4409 4410 /* 4411 * If PF_INET or PF_INET6, check name_bind permission for the port. 4412 * Multiple address binding for SCTP is not supported yet: we just 4413 * check the first address now. 4414 */ 4415 family = sk->sk_family; 4416 if (family == PF_INET || family == PF_INET6) { 4417 char *addrp; 4418 struct sk_security_struct *sksec = sk->sk_security; 4419 struct common_audit_data ad; 4420 struct lsm_network_audit net = {0,}; 4421 struct sockaddr_in *addr4 = NULL; 4422 struct sockaddr_in6 *addr6 = NULL; 4423 unsigned short snum; 4424 u32 sid, node_perm; 4425 4426 if (family == PF_INET) { 4427 addr4 = (struct sockaddr_in *)address; 4428 snum = ntohs(addr4->sin_port); 4429 addrp = (char *)&addr4->sin_addr.s_addr; 4430 } else { 4431 addr6 = (struct sockaddr_in6 *)address; 4432 snum = ntohs(addr6->sin6_port); 4433 addrp = (char *)&addr6->sin6_addr.s6_addr; 4434 } 4435 4436 if (snum) { 4437 int low, high; 4438 4439 inet_get_local_port_range(sock_net(sk), &low, &high); 4440 4441 if (snum < max(PROT_SOCK, low) || snum > high) { 4442 err = sel_netport_sid(sk->sk_protocol, 4443 snum, &sid); 4444 if (err) 4445 goto out; 4446 ad.type = LSM_AUDIT_DATA_NET; 4447 ad.u.net = &net; 4448 ad.u.net->sport = htons(snum); 4449 ad.u.net->family = family; 4450 err = avc_has_perm(sksec->sid, sid, 4451 sksec->sclass, 4452 SOCKET__NAME_BIND, &ad); 4453 if (err) 4454 goto out; 4455 } 4456 } 4457 4458 switch (sksec->sclass) { 4459 case SECCLASS_TCP_SOCKET: 4460 node_perm = TCP_SOCKET__NODE_BIND; 4461 break; 4462 4463 case SECCLASS_UDP_SOCKET: 4464 node_perm = UDP_SOCKET__NODE_BIND; 4465 break; 4466 4467 case SECCLASS_DCCP_SOCKET: 4468 node_perm = DCCP_SOCKET__NODE_BIND; 4469 break; 4470 4471 default: 4472 node_perm = RAWIP_SOCKET__NODE_BIND; 4473 break; 4474 } 4475 4476 err = sel_netnode_sid(addrp, family, &sid); 4477 if (err) 4478 goto out; 4479 4480 ad.type = LSM_AUDIT_DATA_NET; 4481 ad.u.net = &net; 4482 ad.u.net->sport = htons(snum); 4483 ad.u.net->family = family; 4484 4485 if (family == PF_INET) 4486 ad.u.net->v4info.saddr = addr4->sin_addr.s_addr; 4487 else 4488 ad.u.net->v6info.saddr = addr6->sin6_addr; 4489 4490 err = avc_has_perm(sksec->sid, sid, 4491 sksec->sclass, node_perm, &ad); 4492 if (err) 4493 goto out; 4494 } 4495 out: 4496 return err; 4497 } 4498 4499 static int selinux_socket_connect(struct socket *sock, struct sockaddr *address, int addrlen) 4500 { 4501 struct sock *sk = sock->sk; 4502 struct sk_security_struct *sksec = sk->sk_security; 4503 int err; 4504 4505 err = sock_has_perm(current, sk, SOCKET__CONNECT); 4506 if (err) 4507 return err; 4508 4509 /* 4510 * If a TCP or DCCP socket, check name_connect permission for the port. 4511 */ 4512 if (sksec->sclass == SECCLASS_TCP_SOCKET || 4513 sksec->sclass == SECCLASS_DCCP_SOCKET) { 4514 struct common_audit_data ad; 4515 struct lsm_network_audit net = {0,}; 4516 struct sockaddr_in *addr4 = NULL; 4517 struct sockaddr_in6 *addr6 = NULL; 4518 unsigned short snum; 4519 u32 sid, perm; 4520 4521 if (sk->sk_family == PF_INET) { 4522 addr4 = (struct sockaddr_in *)address; 4523 if (addrlen < sizeof(struct sockaddr_in)) 4524 return -EINVAL; 4525 snum = ntohs(addr4->sin_port); 4526 } else { 4527 addr6 = (struct sockaddr_in6 *)address; 4528 if (addrlen < SIN6_LEN_RFC2133) 4529 return -EINVAL; 4530 snum = ntohs(addr6->sin6_port); 4531 } 4532 4533 err = sel_netport_sid(sk->sk_protocol, snum, &sid); 4534 if (err) 4535 goto out; 4536 4537 perm = (sksec->sclass == SECCLASS_TCP_SOCKET) ? 4538 TCP_SOCKET__NAME_CONNECT : DCCP_SOCKET__NAME_CONNECT; 4539 4540 ad.type = LSM_AUDIT_DATA_NET; 4541 ad.u.net = &net; 4542 ad.u.net->dport = htons(snum); 4543 ad.u.net->family = sk->sk_family; 4544 err = avc_has_perm(sksec->sid, sid, sksec->sclass, perm, &ad); 4545 if (err) 4546 goto out; 4547 } 4548 4549 err = selinux_netlbl_socket_connect(sk, address); 4550 4551 out: 4552 return err; 4553 } 4554 4555 static int selinux_socket_listen(struct socket *sock, int backlog) 4556 { 4557 return sock_has_perm(current, sock->sk, SOCKET__LISTEN); 4558 } 4559 4560 static int selinux_socket_accept(struct socket *sock, struct socket *newsock) 4561 { 4562 int err; 4563 struct inode_security_struct *isec; 4564 struct inode_security_struct *newisec; 4565 u16 sclass; 4566 u32 sid; 4567 4568 err = sock_has_perm(current, sock->sk, SOCKET__ACCEPT); 4569 if (err) 4570 return err; 4571 4572 isec = inode_security_novalidate(SOCK_INODE(sock)); 4573 spin_lock(&isec->lock); 4574 sclass = isec->sclass; 4575 sid = isec->sid; 4576 spin_unlock(&isec->lock); 4577 4578 newisec = inode_security_novalidate(SOCK_INODE(newsock)); 4579 newisec->sclass = sclass; 4580 newisec->sid = sid; 4581 newisec->initialized = LABEL_INITIALIZED; 4582 4583 return 0; 4584 } 4585 4586 static int selinux_socket_sendmsg(struct socket *sock, struct msghdr *msg, 4587 int size) 4588 { 4589 return sock_has_perm(current, sock->sk, SOCKET__WRITE); 4590 } 4591 4592 static int selinux_socket_recvmsg(struct socket *sock, struct msghdr *msg, 4593 int size, int flags) 4594 { 4595 return sock_has_perm(current, sock->sk, SOCKET__READ); 4596 } 4597 4598 static int selinux_socket_getsockname(struct socket *sock) 4599 { 4600 return sock_has_perm(current, sock->sk, SOCKET__GETATTR); 4601 } 4602 4603 static int selinux_socket_getpeername(struct socket *sock) 4604 { 4605 return sock_has_perm(current, sock->sk, SOCKET__GETATTR); 4606 } 4607 4608 static int selinux_socket_setsockopt(struct socket *sock, int level, int optname) 4609 { 4610 int err; 4611 4612 err = sock_has_perm(current, sock->sk, SOCKET__SETOPT); 4613 if (err) 4614 return err; 4615 4616 return selinux_netlbl_socket_setsockopt(sock, level, optname); 4617 } 4618 4619 static int selinux_socket_getsockopt(struct socket *sock, int level, 4620 int optname) 4621 { 4622 return sock_has_perm(current, sock->sk, SOCKET__GETOPT); 4623 } 4624 4625 static int selinux_socket_shutdown(struct socket *sock, int how) 4626 { 4627 return sock_has_perm(current, sock->sk, SOCKET__SHUTDOWN); 4628 } 4629 4630 static int selinux_socket_unix_stream_connect(struct sock *sock, 4631 struct sock *other, 4632 struct sock *newsk) 4633 { 4634 struct sk_security_struct *sksec_sock = sock->sk_security; 4635 struct sk_security_struct *sksec_other = other->sk_security; 4636 struct sk_security_struct *sksec_new = newsk->sk_security; 4637 struct common_audit_data ad; 4638 struct lsm_network_audit net = {0,}; 4639 int err; 4640 4641 ad.type = LSM_AUDIT_DATA_NET; 4642 ad.u.net = &net; 4643 ad.u.net->sk = other; 4644 4645 err = avc_has_perm(sksec_sock->sid, sksec_other->sid, 4646 sksec_other->sclass, 4647 UNIX_STREAM_SOCKET__CONNECTTO, &ad); 4648 if (err) 4649 return err; 4650 4651 /* server child socket */ 4652 sksec_new->peer_sid = sksec_sock->sid; 4653 err = security_sid_mls_copy(sksec_other->sid, sksec_sock->sid, 4654 &sksec_new->sid); 4655 if (err) 4656 return err; 4657 4658 /* connecting socket */ 4659 sksec_sock->peer_sid = sksec_new->sid; 4660 4661 return 0; 4662 } 4663 4664 static int selinux_socket_unix_may_send(struct socket *sock, 4665 struct socket *other) 4666 { 4667 struct sk_security_struct *ssec = sock->sk->sk_security; 4668 struct sk_security_struct *osec = other->sk->sk_security; 4669 struct common_audit_data ad; 4670 struct lsm_network_audit net = {0,}; 4671 4672 ad.type = LSM_AUDIT_DATA_NET; 4673 ad.u.net = &net; 4674 ad.u.net->sk = other->sk; 4675 4676 return avc_has_perm(ssec->sid, osec->sid, osec->sclass, SOCKET__SENDTO, 4677 &ad); 4678 } 4679 4680 static int selinux_inet_sys_rcv_skb(struct net *ns, int ifindex, 4681 char *addrp, u16 family, u32 peer_sid, 4682 struct common_audit_data *ad) 4683 { 4684 int err; 4685 u32 if_sid; 4686 u32 node_sid; 4687 4688 err = sel_netif_sid(ns, ifindex, &if_sid); 4689 if (err) 4690 return err; 4691 err = avc_has_perm(peer_sid, if_sid, 4692 SECCLASS_NETIF, NETIF__INGRESS, ad); 4693 if (err) 4694 return err; 4695 4696 err = sel_netnode_sid(addrp, family, &node_sid); 4697 if (err) 4698 return err; 4699 return avc_has_perm(peer_sid, node_sid, 4700 SECCLASS_NODE, NODE__RECVFROM, ad); 4701 } 4702 4703 static int selinux_sock_rcv_skb_compat(struct sock *sk, struct sk_buff *skb, 4704 u16 family) 4705 { 4706 int err = 0; 4707 struct sk_security_struct *sksec = sk->sk_security; 4708 u32 sk_sid = sksec->sid; 4709 struct common_audit_data ad; 4710 struct lsm_network_audit net = {0,}; 4711 char *addrp; 4712 4713 ad.type = LSM_AUDIT_DATA_NET; 4714 ad.u.net = &net; 4715 ad.u.net->netif = skb->skb_iif; 4716 ad.u.net->family = family; 4717 err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL); 4718 if (err) 4719 return err; 4720 4721 if (selinux_secmark_enabled()) { 4722 err = avc_has_perm(sk_sid, skb->secmark, SECCLASS_PACKET, 4723 PACKET__RECV, &ad); 4724 if (err) 4725 return err; 4726 } 4727 4728 err = selinux_netlbl_sock_rcv_skb(sksec, skb, family, &ad); 4729 if (err) 4730 return err; 4731 err = selinux_xfrm_sock_rcv_skb(sksec->sid, skb, &ad); 4732 4733 return err; 4734 } 4735 4736 static int selinux_socket_sock_rcv_skb(struct sock *sk, struct sk_buff *skb) 4737 { 4738 int err; 4739 struct sk_security_struct *sksec = sk->sk_security; 4740 u16 family = sk->sk_family; 4741 u32 sk_sid = sksec->sid; 4742 struct common_audit_data ad; 4743 struct lsm_network_audit net = {0,}; 4744 char *addrp; 4745 u8 secmark_active; 4746 u8 peerlbl_active; 4747 4748 if (family != PF_INET && family != PF_INET6) 4749 return 0; 4750 4751 /* Handle mapped IPv4 packets arriving via IPv6 sockets */ 4752 if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP)) 4753 family = PF_INET; 4754 4755 /* If any sort of compatibility mode is enabled then handoff processing 4756 * to the selinux_sock_rcv_skb_compat() function to deal with the 4757 * special handling. We do this in an attempt to keep this function 4758 * as fast and as clean as possible. */ 4759 if (!selinux_policycap_netpeer) 4760 return selinux_sock_rcv_skb_compat(sk, skb, family); 4761 4762 secmark_active = selinux_secmark_enabled(); 4763 peerlbl_active = selinux_peerlbl_enabled(); 4764 if (!secmark_active && !peerlbl_active) 4765 return 0; 4766 4767 ad.type = LSM_AUDIT_DATA_NET; 4768 ad.u.net = &net; 4769 ad.u.net->netif = skb->skb_iif; 4770 ad.u.net->family = family; 4771 err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL); 4772 if (err) 4773 return err; 4774 4775 if (peerlbl_active) { 4776 u32 peer_sid; 4777 4778 err = selinux_skb_peerlbl_sid(skb, family, &peer_sid); 4779 if (err) 4780 return err; 4781 err = selinux_inet_sys_rcv_skb(sock_net(sk), skb->skb_iif, 4782 addrp, family, peer_sid, &ad); 4783 if (err) { 4784 selinux_netlbl_err(skb, family, err, 0); 4785 return err; 4786 } 4787 err = avc_has_perm(sk_sid, peer_sid, SECCLASS_PEER, 4788 PEER__RECV, &ad); 4789 if (err) { 4790 selinux_netlbl_err(skb, family, err, 0); 4791 return err; 4792 } 4793 } 4794 4795 if (secmark_active) { 4796 err = avc_has_perm(sk_sid, skb->secmark, SECCLASS_PACKET, 4797 PACKET__RECV, &ad); 4798 if (err) 4799 return err; 4800 } 4801 4802 return err; 4803 } 4804 4805 static int selinux_socket_getpeersec_stream(struct socket *sock, char __user *optval, 4806 int __user *optlen, unsigned len) 4807 { 4808 int err = 0; 4809 char *scontext; 4810 u32 scontext_len; 4811 struct sk_security_struct *sksec = sock->sk->sk_security; 4812 u32 peer_sid = SECSID_NULL; 4813 4814 if (sksec->sclass == SECCLASS_UNIX_STREAM_SOCKET || 4815 sksec->sclass == SECCLASS_TCP_SOCKET) 4816 peer_sid = sksec->peer_sid; 4817 if (peer_sid == SECSID_NULL) 4818 return -ENOPROTOOPT; 4819 4820 err = security_sid_to_context(peer_sid, &scontext, &scontext_len); 4821 if (err) 4822 return err; 4823 4824 if (scontext_len > len) { 4825 err = -ERANGE; 4826 goto out_len; 4827 } 4828 4829 if (copy_to_user(optval, scontext, scontext_len)) 4830 err = -EFAULT; 4831 4832 out_len: 4833 if (put_user(scontext_len, optlen)) 4834 err = -EFAULT; 4835 kfree(scontext); 4836 return err; 4837 } 4838 4839 static int selinux_socket_getpeersec_dgram(struct socket *sock, struct sk_buff *skb, u32 *secid) 4840 { 4841 u32 peer_secid = SECSID_NULL; 4842 u16 family; 4843 struct inode_security_struct *isec; 4844 4845 if (skb && skb->protocol == htons(ETH_P_IP)) 4846 family = PF_INET; 4847 else if (skb && skb->protocol == htons(ETH_P_IPV6)) 4848 family = PF_INET6; 4849 else if (sock) 4850 family = sock->sk->sk_family; 4851 else 4852 goto out; 4853 4854 if (sock && family == PF_UNIX) { 4855 isec = inode_security_novalidate(SOCK_INODE(sock)); 4856 peer_secid = isec->sid; 4857 } else if (skb) 4858 selinux_skb_peerlbl_sid(skb, family, &peer_secid); 4859 4860 out: 4861 *secid = peer_secid; 4862 if (peer_secid == SECSID_NULL) 4863 return -EINVAL; 4864 return 0; 4865 } 4866 4867 static int selinux_sk_alloc_security(struct sock *sk, int family, gfp_t priority) 4868 { 4869 struct sk_security_struct *sksec; 4870 4871 sksec = kzalloc(sizeof(*sksec), priority); 4872 if (!sksec) 4873 return -ENOMEM; 4874 4875 sksec->peer_sid = SECINITSID_UNLABELED; 4876 sksec->sid = SECINITSID_UNLABELED; 4877 sksec->sclass = SECCLASS_SOCKET; 4878 selinux_netlbl_sk_security_reset(sksec); 4879 sk->sk_security = sksec; 4880 4881 return 0; 4882 } 4883 4884 static void selinux_sk_free_security(struct sock *sk) 4885 { 4886 struct sk_security_struct *sksec = sk->sk_security; 4887 4888 sk->sk_security = NULL; 4889 selinux_netlbl_sk_security_free(sksec); 4890 kfree(sksec); 4891 } 4892 4893 static void selinux_sk_clone_security(const struct sock *sk, struct sock *newsk) 4894 { 4895 struct sk_security_struct *sksec = sk->sk_security; 4896 struct sk_security_struct *newsksec = newsk->sk_security; 4897 4898 newsksec->sid = sksec->sid; 4899 newsksec->peer_sid = sksec->peer_sid; 4900 newsksec->sclass = sksec->sclass; 4901 4902 selinux_netlbl_sk_security_reset(newsksec); 4903 } 4904 4905 static void selinux_sk_getsecid(struct sock *sk, u32 *secid) 4906 { 4907 if (!sk) 4908 *secid = SECINITSID_ANY_SOCKET; 4909 else { 4910 struct sk_security_struct *sksec = sk->sk_security; 4911 4912 *secid = sksec->sid; 4913 } 4914 } 4915 4916 static void selinux_sock_graft(struct sock *sk, struct socket *parent) 4917 { 4918 struct inode_security_struct *isec = 4919 inode_security_novalidate(SOCK_INODE(parent)); 4920 struct sk_security_struct *sksec = sk->sk_security; 4921 4922 if (sk->sk_family == PF_INET || sk->sk_family == PF_INET6 || 4923 sk->sk_family == PF_UNIX) 4924 isec->sid = sksec->sid; 4925 sksec->sclass = isec->sclass; 4926 } 4927 4928 static int selinux_inet_conn_request(struct sock *sk, struct sk_buff *skb, 4929 struct request_sock *req) 4930 { 4931 struct sk_security_struct *sksec = sk->sk_security; 4932 int err; 4933 u16 family = req->rsk_ops->family; 4934 u32 connsid; 4935 u32 peersid; 4936 4937 err = selinux_skb_peerlbl_sid(skb, family, &peersid); 4938 if (err) 4939 return err; 4940 err = selinux_conn_sid(sksec->sid, peersid, &connsid); 4941 if (err) 4942 return err; 4943 req->secid = connsid; 4944 req->peer_secid = peersid; 4945 4946 return selinux_netlbl_inet_conn_request(req, family); 4947 } 4948 4949 static void selinux_inet_csk_clone(struct sock *newsk, 4950 const struct request_sock *req) 4951 { 4952 struct sk_security_struct *newsksec = newsk->sk_security; 4953 4954 newsksec->sid = req->secid; 4955 newsksec->peer_sid = req->peer_secid; 4956 /* NOTE: Ideally, we should also get the isec->sid for the 4957 new socket in sync, but we don't have the isec available yet. 4958 So we will wait until sock_graft to do it, by which 4959 time it will have been created and available. */ 4960 4961 /* We don't need to take any sort of lock here as we are the only 4962 * thread with access to newsksec */ 4963 selinux_netlbl_inet_csk_clone(newsk, req->rsk_ops->family); 4964 } 4965 4966 static void selinux_inet_conn_established(struct sock *sk, struct sk_buff *skb) 4967 { 4968 u16 family = sk->sk_family; 4969 struct sk_security_struct *sksec = sk->sk_security; 4970 4971 /* handle mapped IPv4 packets arriving via IPv6 sockets */ 4972 if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP)) 4973 family = PF_INET; 4974 4975 selinux_skb_peerlbl_sid(skb, family, &sksec->peer_sid); 4976 } 4977 4978 static int selinux_secmark_relabel_packet(u32 sid) 4979 { 4980 const struct task_security_struct *__tsec; 4981 u32 tsid; 4982 4983 __tsec = current_security(); 4984 tsid = __tsec->sid; 4985 4986 return avc_has_perm(tsid, sid, SECCLASS_PACKET, PACKET__RELABELTO, NULL); 4987 } 4988 4989 static void selinux_secmark_refcount_inc(void) 4990 { 4991 atomic_inc(&selinux_secmark_refcount); 4992 } 4993 4994 static void selinux_secmark_refcount_dec(void) 4995 { 4996 atomic_dec(&selinux_secmark_refcount); 4997 } 4998 4999 static void selinux_req_classify_flow(const struct request_sock *req, 5000 struct flowi *fl) 5001 { 5002 fl->flowi_secid = req->secid; 5003 } 5004 5005 static int selinux_tun_dev_alloc_security(void **security) 5006 { 5007 struct tun_security_struct *tunsec; 5008 5009 tunsec = kzalloc(sizeof(*tunsec), GFP_KERNEL); 5010 if (!tunsec) 5011 return -ENOMEM; 5012 tunsec->sid = current_sid(); 5013 5014 *security = tunsec; 5015 return 0; 5016 } 5017 5018 static void selinux_tun_dev_free_security(void *security) 5019 { 5020 kfree(security); 5021 } 5022 5023 static int selinux_tun_dev_create(void) 5024 { 5025 u32 sid = current_sid(); 5026 5027 /* we aren't taking into account the "sockcreate" SID since the socket 5028 * that is being created here is not a socket in the traditional sense, 5029 * instead it is a private sock, accessible only to the kernel, and 5030 * representing a wide range of network traffic spanning multiple 5031 * connections unlike traditional sockets - check the TUN driver to 5032 * get a better understanding of why this socket is special */ 5033 5034 return avc_has_perm(sid, sid, SECCLASS_TUN_SOCKET, TUN_SOCKET__CREATE, 5035 NULL); 5036 } 5037 5038 static int selinux_tun_dev_attach_queue(void *security) 5039 { 5040 struct tun_security_struct *tunsec = security; 5041 5042 return avc_has_perm(current_sid(), tunsec->sid, SECCLASS_TUN_SOCKET, 5043 TUN_SOCKET__ATTACH_QUEUE, NULL); 5044 } 5045 5046 static int selinux_tun_dev_attach(struct sock *sk, void *security) 5047 { 5048 struct tun_security_struct *tunsec = security; 5049 struct sk_security_struct *sksec = sk->sk_security; 5050 5051 /* we don't currently perform any NetLabel based labeling here and it 5052 * isn't clear that we would want to do so anyway; while we could apply 5053 * labeling without the support of the TUN user the resulting labeled 5054 * traffic from the other end of the connection would almost certainly 5055 * cause confusion to the TUN user that had no idea network labeling 5056 * protocols were being used */ 5057 5058 sksec->sid = tunsec->sid; 5059 sksec->sclass = SECCLASS_TUN_SOCKET; 5060 5061 return 0; 5062 } 5063 5064 static int selinux_tun_dev_open(void *security) 5065 { 5066 struct tun_security_struct *tunsec = security; 5067 u32 sid = current_sid(); 5068 int err; 5069 5070 err = avc_has_perm(sid, tunsec->sid, SECCLASS_TUN_SOCKET, 5071 TUN_SOCKET__RELABELFROM, NULL); 5072 if (err) 5073 return err; 5074 err = avc_has_perm(sid, sid, SECCLASS_TUN_SOCKET, 5075 TUN_SOCKET__RELABELTO, NULL); 5076 if (err) 5077 return err; 5078 tunsec->sid = sid; 5079 5080 return 0; 5081 } 5082 5083 static int selinux_nlmsg_perm(struct sock *sk, struct sk_buff *skb) 5084 { 5085 int err = 0; 5086 u32 perm; 5087 struct nlmsghdr *nlh; 5088 struct sk_security_struct *sksec = sk->sk_security; 5089 5090 if (skb->len < NLMSG_HDRLEN) { 5091 err = -EINVAL; 5092 goto out; 5093 } 5094 nlh = nlmsg_hdr(skb); 5095 5096 err = selinux_nlmsg_lookup(sksec->sclass, nlh->nlmsg_type, &perm); 5097 if (err) { 5098 if (err == -EINVAL) { 5099 pr_warn_ratelimited("SELinux: unrecognized netlink" 5100 " message: protocol=%hu nlmsg_type=%hu sclass=%s" 5101 " pig=%d comm=%s\n", 5102 sk->sk_protocol, nlh->nlmsg_type, 5103 secclass_map[sksec->sclass - 1].name, 5104 task_pid_nr(current), current->comm); 5105 if (!selinux_enforcing || security_get_allow_unknown()) 5106 err = 0; 5107 } 5108 5109 /* Ignore */ 5110 if (err == -ENOENT) 5111 err = 0; 5112 goto out; 5113 } 5114 5115 err = sock_has_perm(current, sk, perm); 5116 out: 5117 return err; 5118 } 5119 5120 #ifdef CONFIG_NETFILTER 5121 5122 static unsigned int selinux_ip_forward(struct sk_buff *skb, 5123 const struct net_device *indev, 5124 u16 family) 5125 { 5126 int err; 5127 char *addrp; 5128 u32 peer_sid; 5129 struct common_audit_data ad; 5130 struct lsm_network_audit net = {0,}; 5131 u8 secmark_active; 5132 u8 netlbl_active; 5133 u8 peerlbl_active; 5134 5135 if (!selinux_policycap_netpeer) 5136 return NF_ACCEPT; 5137 5138 secmark_active = selinux_secmark_enabled(); 5139 netlbl_active = netlbl_enabled(); 5140 peerlbl_active = selinux_peerlbl_enabled(); 5141 if (!secmark_active && !peerlbl_active) 5142 return NF_ACCEPT; 5143 5144 if (selinux_skb_peerlbl_sid(skb, family, &peer_sid) != 0) 5145 return NF_DROP; 5146 5147 ad.type = LSM_AUDIT_DATA_NET; 5148 ad.u.net = &net; 5149 ad.u.net->netif = indev->ifindex; 5150 ad.u.net->family = family; 5151 if (selinux_parse_skb(skb, &ad, &addrp, 1, NULL) != 0) 5152 return NF_DROP; 5153 5154 if (peerlbl_active) { 5155 err = selinux_inet_sys_rcv_skb(dev_net(indev), indev->ifindex, 5156 addrp, family, peer_sid, &ad); 5157 if (err) { 5158 selinux_netlbl_err(skb, family, err, 1); 5159 return NF_DROP; 5160 } 5161 } 5162 5163 if (secmark_active) 5164 if (avc_has_perm(peer_sid, skb->secmark, 5165 SECCLASS_PACKET, PACKET__FORWARD_IN, &ad)) 5166 return NF_DROP; 5167 5168 if (netlbl_active) 5169 /* we do this in the FORWARD path and not the POST_ROUTING 5170 * path because we want to make sure we apply the necessary 5171 * labeling before IPsec is applied so we can leverage AH 5172 * protection */ 5173 if (selinux_netlbl_skbuff_setsid(skb, family, peer_sid) != 0) 5174 return NF_DROP; 5175 5176 return NF_ACCEPT; 5177 } 5178 5179 static unsigned int selinux_ipv4_forward(void *priv, 5180 struct sk_buff *skb, 5181 const struct nf_hook_state *state) 5182 { 5183 return selinux_ip_forward(skb, state->in, PF_INET); 5184 } 5185 5186 #if IS_ENABLED(CONFIG_IPV6) 5187 static unsigned int selinux_ipv6_forward(void *priv, 5188 struct sk_buff *skb, 5189 const struct nf_hook_state *state) 5190 { 5191 return selinux_ip_forward(skb, state->in, PF_INET6); 5192 } 5193 #endif /* IPV6 */ 5194 5195 static unsigned int selinux_ip_output(struct sk_buff *skb, 5196 u16 family) 5197 { 5198 struct sock *sk; 5199 u32 sid; 5200 5201 if (!netlbl_enabled()) 5202 return NF_ACCEPT; 5203 5204 /* we do this in the LOCAL_OUT path and not the POST_ROUTING path 5205 * because we want to make sure we apply the necessary labeling 5206 * before IPsec is applied so we can leverage AH protection */ 5207 sk = skb->sk; 5208 if (sk) { 5209 struct sk_security_struct *sksec; 5210 5211 if (sk_listener(sk)) 5212 /* if the socket is the listening state then this 5213 * packet is a SYN-ACK packet which means it needs to 5214 * be labeled based on the connection/request_sock and 5215 * not the parent socket. unfortunately, we can't 5216 * lookup the request_sock yet as it isn't queued on 5217 * the parent socket until after the SYN-ACK is sent. 5218 * the "solution" is to simply pass the packet as-is 5219 * as any IP option based labeling should be copied 5220 * from the initial connection request (in the IP 5221 * layer). it is far from ideal, but until we get a 5222 * security label in the packet itself this is the 5223 * best we can do. */ 5224 return NF_ACCEPT; 5225 5226 /* standard practice, label using the parent socket */ 5227 sksec = sk->sk_security; 5228 sid = sksec->sid; 5229 } else 5230 sid = SECINITSID_KERNEL; 5231 if (selinux_netlbl_skbuff_setsid(skb, family, sid) != 0) 5232 return NF_DROP; 5233 5234 return NF_ACCEPT; 5235 } 5236 5237 static unsigned int selinux_ipv4_output(void *priv, 5238 struct sk_buff *skb, 5239 const struct nf_hook_state *state) 5240 { 5241 return selinux_ip_output(skb, PF_INET); 5242 } 5243 5244 #if IS_ENABLED(CONFIG_IPV6) 5245 static unsigned int selinux_ipv6_output(void *priv, 5246 struct sk_buff *skb, 5247 const struct nf_hook_state *state) 5248 { 5249 return selinux_ip_output(skb, PF_INET6); 5250 } 5251 #endif /* IPV6 */ 5252 5253 static unsigned int selinux_ip_postroute_compat(struct sk_buff *skb, 5254 int ifindex, 5255 u16 family) 5256 { 5257 struct sock *sk = skb_to_full_sk(skb); 5258 struct sk_security_struct *sksec; 5259 struct common_audit_data ad; 5260 struct lsm_network_audit net = {0,}; 5261 char *addrp; 5262 u8 proto; 5263 5264 if (sk == NULL) 5265 return NF_ACCEPT; 5266 sksec = sk->sk_security; 5267 5268 ad.type = LSM_AUDIT_DATA_NET; 5269 ad.u.net = &net; 5270 ad.u.net->netif = ifindex; 5271 ad.u.net->family = family; 5272 if (selinux_parse_skb(skb, &ad, &addrp, 0, &proto)) 5273 return NF_DROP; 5274 5275 if (selinux_secmark_enabled()) 5276 if (avc_has_perm(sksec->sid, skb->secmark, 5277 SECCLASS_PACKET, PACKET__SEND, &ad)) 5278 return NF_DROP_ERR(-ECONNREFUSED); 5279 5280 if (selinux_xfrm_postroute_last(sksec->sid, skb, &ad, proto)) 5281 return NF_DROP_ERR(-ECONNREFUSED); 5282 5283 return NF_ACCEPT; 5284 } 5285 5286 static unsigned int selinux_ip_postroute(struct sk_buff *skb, 5287 const struct net_device *outdev, 5288 u16 family) 5289 { 5290 u32 secmark_perm; 5291 u32 peer_sid; 5292 int ifindex = outdev->ifindex; 5293 struct sock *sk; 5294 struct common_audit_data ad; 5295 struct lsm_network_audit net = {0,}; 5296 char *addrp; 5297 u8 secmark_active; 5298 u8 peerlbl_active; 5299 5300 /* If any sort of compatibility mode is enabled then handoff processing 5301 * to the selinux_ip_postroute_compat() function to deal with the 5302 * special handling. We do this in an attempt to keep this function 5303 * as fast and as clean as possible. */ 5304 if (!selinux_policycap_netpeer) 5305 return selinux_ip_postroute_compat(skb, ifindex, family); 5306 5307 secmark_active = selinux_secmark_enabled(); 5308 peerlbl_active = selinux_peerlbl_enabled(); 5309 if (!secmark_active && !peerlbl_active) 5310 return NF_ACCEPT; 5311 5312 sk = skb_to_full_sk(skb); 5313 5314 #ifdef CONFIG_XFRM 5315 /* If skb->dst->xfrm is non-NULL then the packet is undergoing an IPsec 5316 * packet transformation so allow the packet to pass without any checks 5317 * since we'll have another chance to perform access control checks 5318 * when the packet is on it's final way out. 5319 * NOTE: there appear to be some IPv6 multicast cases where skb->dst 5320 * is NULL, in this case go ahead and apply access control. 5321 * NOTE: if this is a local socket (skb->sk != NULL) that is in the 5322 * TCP listening state we cannot wait until the XFRM processing 5323 * is done as we will miss out on the SA label if we do; 5324 * unfortunately, this means more work, but it is only once per 5325 * connection. */ 5326 if (skb_dst(skb) != NULL && skb_dst(skb)->xfrm != NULL && 5327 !(sk && sk_listener(sk))) 5328 return NF_ACCEPT; 5329 #endif 5330 5331 if (sk == NULL) { 5332 /* Without an associated socket the packet is either coming 5333 * from the kernel or it is being forwarded; check the packet 5334 * to determine which and if the packet is being forwarded 5335 * query the packet directly to determine the security label. */ 5336 if (skb->skb_iif) { 5337 secmark_perm = PACKET__FORWARD_OUT; 5338 if (selinux_skb_peerlbl_sid(skb, family, &peer_sid)) 5339 return NF_DROP; 5340 } else { 5341 secmark_perm = PACKET__SEND; 5342 peer_sid = SECINITSID_KERNEL; 5343 } 5344 } else if (sk_listener(sk)) { 5345 /* Locally generated packet but the associated socket is in the 5346 * listening state which means this is a SYN-ACK packet. In 5347 * this particular case the correct security label is assigned 5348 * to the connection/request_sock but unfortunately we can't 5349 * query the request_sock as it isn't queued on the parent 5350 * socket until after the SYN-ACK packet is sent; the only 5351 * viable choice is to regenerate the label like we do in 5352 * selinux_inet_conn_request(). See also selinux_ip_output() 5353 * for similar problems. */ 5354 u32 skb_sid; 5355 struct sk_security_struct *sksec; 5356 5357 sksec = sk->sk_security; 5358 if (selinux_skb_peerlbl_sid(skb, family, &skb_sid)) 5359 return NF_DROP; 5360 /* At this point, if the returned skb peerlbl is SECSID_NULL 5361 * and the packet has been through at least one XFRM 5362 * transformation then we must be dealing with the "final" 5363 * form of labeled IPsec packet; since we've already applied 5364 * all of our access controls on this packet we can safely 5365 * pass the packet. */ 5366 if (skb_sid == SECSID_NULL) { 5367 switch (family) { 5368 case PF_INET: 5369 if (IPCB(skb)->flags & IPSKB_XFRM_TRANSFORMED) 5370 return NF_ACCEPT; 5371 break; 5372 case PF_INET6: 5373 if (IP6CB(skb)->flags & IP6SKB_XFRM_TRANSFORMED) 5374 return NF_ACCEPT; 5375 break; 5376 default: 5377 return NF_DROP_ERR(-ECONNREFUSED); 5378 } 5379 } 5380 if (selinux_conn_sid(sksec->sid, skb_sid, &peer_sid)) 5381 return NF_DROP; 5382 secmark_perm = PACKET__SEND; 5383 } else { 5384 /* Locally generated packet, fetch the security label from the 5385 * associated socket. */ 5386 struct sk_security_struct *sksec = sk->sk_security; 5387 peer_sid = sksec->sid; 5388 secmark_perm = PACKET__SEND; 5389 } 5390 5391 ad.type = LSM_AUDIT_DATA_NET; 5392 ad.u.net = &net; 5393 ad.u.net->netif = ifindex; 5394 ad.u.net->family = family; 5395 if (selinux_parse_skb(skb, &ad, &addrp, 0, NULL)) 5396 return NF_DROP; 5397 5398 if (secmark_active) 5399 if (avc_has_perm(peer_sid, skb->secmark, 5400 SECCLASS_PACKET, secmark_perm, &ad)) 5401 return NF_DROP_ERR(-ECONNREFUSED); 5402 5403 if (peerlbl_active) { 5404 u32 if_sid; 5405 u32 node_sid; 5406 5407 if (sel_netif_sid(dev_net(outdev), ifindex, &if_sid)) 5408 return NF_DROP; 5409 if (avc_has_perm(peer_sid, if_sid, 5410 SECCLASS_NETIF, NETIF__EGRESS, &ad)) 5411 return NF_DROP_ERR(-ECONNREFUSED); 5412 5413 if (sel_netnode_sid(addrp, family, &node_sid)) 5414 return NF_DROP; 5415 if (avc_has_perm(peer_sid, node_sid, 5416 SECCLASS_NODE, NODE__SENDTO, &ad)) 5417 return NF_DROP_ERR(-ECONNREFUSED); 5418 } 5419 5420 return NF_ACCEPT; 5421 } 5422 5423 static unsigned int selinux_ipv4_postroute(void *priv, 5424 struct sk_buff *skb, 5425 const struct nf_hook_state *state) 5426 { 5427 return selinux_ip_postroute(skb, state->out, PF_INET); 5428 } 5429 5430 #if IS_ENABLED(CONFIG_IPV6) 5431 static unsigned int selinux_ipv6_postroute(void *priv, 5432 struct sk_buff *skb, 5433 const struct nf_hook_state *state) 5434 { 5435 return selinux_ip_postroute(skb, state->out, PF_INET6); 5436 } 5437 #endif /* IPV6 */ 5438 5439 #endif /* CONFIG_NETFILTER */ 5440 5441 static int selinux_netlink_send(struct sock *sk, struct sk_buff *skb) 5442 { 5443 return selinux_nlmsg_perm(sk, skb); 5444 } 5445 5446 static int ipc_alloc_security(struct task_struct *task, 5447 struct kern_ipc_perm *perm, 5448 u16 sclass) 5449 { 5450 struct ipc_security_struct *isec; 5451 u32 sid; 5452 5453 isec = kzalloc(sizeof(struct ipc_security_struct), GFP_KERNEL); 5454 if (!isec) 5455 return -ENOMEM; 5456 5457 sid = task_sid(task); 5458 isec->sclass = sclass; 5459 isec->sid = sid; 5460 perm->security = isec; 5461 5462 return 0; 5463 } 5464 5465 static void ipc_free_security(struct kern_ipc_perm *perm) 5466 { 5467 struct ipc_security_struct *isec = perm->security; 5468 perm->security = NULL; 5469 kfree(isec); 5470 } 5471 5472 static int msg_msg_alloc_security(struct msg_msg *msg) 5473 { 5474 struct msg_security_struct *msec; 5475 5476 msec = kzalloc(sizeof(struct msg_security_struct), GFP_KERNEL); 5477 if (!msec) 5478 return -ENOMEM; 5479 5480 msec->sid = SECINITSID_UNLABELED; 5481 msg->security = msec; 5482 5483 return 0; 5484 } 5485 5486 static void msg_msg_free_security(struct msg_msg *msg) 5487 { 5488 struct msg_security_struct *msec = msg->security; 5489 5490 msg->security = NULL; 5491 kfree(msec); 5492 } 5493 5494 static int ipc_has_perm(struct kern_ipc_perm *ipc_perms, 5495 u32 perms) 5496 { 5497 struct ipc_security_struct *isec; 5498 struct common_audit_data ad; 5499 u32 sid = current_sid(); 5500 5501 isec = ipc_perms->security; 5502 5503 ad.type = LSM_AUDIT_DATA_IPC; 5504 ad.u.ipc_id = ipc_perms->key; 5505 5506 return avc_has_perm(sid, isec->sid, isec->sclass, perms, &ad); 5507 } 5508 5509 static int selinux_msg_msg_alloc_security(struct msg_msg *msg) 5510 { 5511 return msg_msg_alloc_security(msg); 5512 } 5513 5514 static void selinux_msg_msg_free_security(struct msg_msg *msg) 5515 { 5516 msg_msg_free_security(msg); 5517 } 5518 5519 /* message queue security operations */ 5520 static int selinux_msg_queue_alloc_security(struct msg_queue *msq) 5521 { 5522 struct ipc_security_struct *isec; 5523 struct common_audit_data ad; 5524 u32 sid = current_sid(); 5525 int rc; 5526 5527 rc = ipc_alloc_security(current, &msq->q_perm, SECCLASS_MSGQ); 5528 if (rc) 5529 return rc; 5530 5531 isec = msq->q_perm.security; 5532 5533 ad.type = LSM_AUDIT_DATA_IPC; 5534 ad.u.ipc_id = msq->q_perm.key; 5535 5536 rc = avc_has_perm(sid, isec->sid, SECCLASS_MSGQ, 5537 MSGQ__CREATE, &ad); 5538 if (rc) { 5539 ipc_free_security(&msq->q_perm); 5540 return rc; 5541 } 5542 return 0; 5543 } 5544 5545 static void selinux_msg_queue_free_security(struct msg_queue *msq) 5546 { 5547 ipc_free_security(&msq->q_perm); 5548 } 5549 5550 static int selinux_msg_queue_associate(struct msg_queue *msq, int msqflg) 5551 { 5552 struct ipc_security_struct *isec; 5553 struct common_audit_data ad; 5554 u32 sid = current_sid(); 5555 5556 isec = msq->q_perm.security; 5557 5558 ad.type = LSM_AUDIT_DATA_IPC; 5559 ad.u.ipc_id = msq->q_perm.key; 5560 5561 return avc_has_perm(sid, isec->sid, SECCLASS_MSGQ, 5562 MSGQ__ASSOCIATE, &ad); 5563 } 5564 5565 static int selinux_msg_queue_msgctl(struct msg_queue *msq, int cmd) 5566 { 5567 int err; 5568 int perms; 5569 5570 switch (cmd) { 5571 case IPC_INFO: 5572 case MSG_INFO: 5573 /* No specific object, just general system-wide information. */ 5574 return task_has_system(current, SYSTEM__IPC_INFO); 5575 case IPC_STAT: 5576 case MSG_STAT: 5577 perms = MSGQ__GETATTR | MSGQ__ASSOCIATE; 5578 break; 5579 case IPC_SET: 5580 perms = MSGQ__SETATTR; 5581 break; 5582 case IPC_RMID: 5583 perms = MSGQ__DESTROY; 5584 break; 5585 default: 5586 return 0; 5587 } 5588 5589 err = ipc_has_perm(&msq->q_perm, perms); 5590 return err; 5591 } 5592 5593 static int selinux_msg_queue_msgsnd(struct msg_queue *msq, struct msg_msg *msg, int msqflg) 5594 { 5595 struct ipc_security_struct *isec; 5596 struct msg_security_struct *msec; 5597 struct common_audit_data ad; 5598 u32 sid = current_sid(); 5599 int rc; 5600 5601 isec = msq->q_perm.security; 5602 msec = msg->security; 5603 5604 /* 5605 * First time through, need to assign label to the message 5606 */ 5607 if (msec->sid == SECINITSID_UNLABELED) { 5608 /* 5609 * Compute new sid based on current process and 5610 * message queue this message will be stored in 5611 */ 5612 rc = security_transition_sid(sid, isec->sid, SECCLASS_MSG, 5613 NULL, &msec->sid); 5614 if (rc) 5615 return rc; 5616 } 5617 5618 ad.type = LSM_AUDIT_DATA_IPC; 5619 ad.u.ipc_id = msq->q_perm.key; 5620 5621 /* Can this process write to the queue? */ 5622 rc = avc_has_perm(sid, isec->sid, SECCLASS_MSGQ, 5623 MSGQ__WRITE, &ad); 5624 if (!rc) 5625 /* Can this process send the message */ 5626 rc = avc_has_perm(sid, msec->sid, SECCLASS_MSG, 5627 MSG__SEND, &ad); 5628 if (!rc) 5629 /* Can the message be put in the queue? */ 5630 rc = avc_has_perm(msec->sid, isec->sid, SECCLASS_MSGQ, 5631 MSGQ__ENQUEUE, &ad); 5632 5633 return rc; 5634 } 5635 5636 static int selinux_msg_queue_msgrcv(struct msg_queue *msq, struct msg_msg *msg, 5637 struct task_struct *target, 5638 long type, int mode) 5639 { 5640 struct ipc_security_struct *isec; 5641 struct msg_security_struct *msec; 5642 struct common_audit_data ad; 5643 u32 sid = task_sid(target); 5644 int rc; 5645 5646 isec = msq->q_perm.security; 5647 msec = msg->security; 5648 5649 ad.type = LSM_AUDIT_DATA_IPC; 5650 ad.u.ipc_id = msq->q_perm.key; 5651 5652 rc = avc_has_perm(sid, isec->sid, 5653 SECCLASS_MSGQ, MSGQ__READ, &ad); 5654 if (!rc) 5655 rc = avc_has_perm(sid, msec->sid, 5656 SECCLASS_MSG, MSG__RECEIVE, &ad); 5657 return rc; 5658 } 5659 5660 /* Shared Memory security operations */ 5661 static int selinux_shm_alloc_security(struct shmid_kernel *shp) 5662 { 5663 struct ipc_security_struct *isec; 5664 struct common_audit_data ad; 5665 u32 sid = current_sid(); 5666 int rc; 5667 5668 rc = ipc_alloc_security(current, &shp->shm_perm, SECCLASS_SHM); 5669 if (rc) 5670 return rc; 5671 5672 isec = shp->shm_perm.security; 5673 5674 ad.type = LSM_AUDIT_DATA_IPC; 5675 ad.u.ipc_id = shp->shm_perm.key; 5676 5677 rc = avc_has_perm(sid, isec->sid, SECCLASS_SHM, 5678 SHM__CREATE, &ad); 5679 if (rc) { 5680 ipc_free_security(&shp->shm_perm); 5681 return rc; 5682 } 5683 return 0; 5684 } 5685 5686 static void selinux_shm_free_security(struct shmid_kernel *shp) 5687 { 5688 ipc_free_security(&shp->shm_perm); 5689 } 5690 5691 static int selinux_shm_associate(struct shmid_kernel *shp, int shmflg) 5692 { 5693 struct ipc_security_struct *isec; 5694 struct common_audit_data ad; 5695 u32 sid = current_sid(); 5696 5697 isec = shp->shm_perm.security; 5698 5699 ad.type = LSM_AUDIT_DATA_IPC; 5700 ad.u.ipc_id = shp->shm_perm.key; 5701 5702 return avc_has_perm(sid, isec->sid, SECCLASS_SHM, 5703 SHM__ASSOCIATE, &ad); 5704 } 5705 5706 /* Note, at this point, shp is locked down */ 5707 static int selinux_shm_shmctl(struct shmid_kernel *shp, int cmd) 5708 { 5709 int perms; 5710 int err; 5711 5712 switch (cmd) { 5713 case IPC_INFO: 5714 case SHM_INFO: 5715 /* No specific object, just general system-wide information. */ 5716 return task_has_system(current, SYSTEM__IPC_INFO); 5717 case IPC_STAT: 5718 case SHM_STAT: 5719 perms = SHM__GETATTR | SHM__ASSOCIATE; 5720 break; 5721 case IPC_SET: 5722 perms = SHM__SETATTR; 5723 break; 5724 case SHM_LOCK: 5725 case SHM_UNLOCK: 5726 perms = SHM__LOCK; 5727 break; 5728 case IPC_RMID: 5729 perms = SHM__DESTROY; 5730 break; 5731 default: 5732 return 0; 5733 } 5734 5735 err = ipc_has_perm(&shp->shm_perm, perms); 5736 return err; 5737 } 5738 5739 static int selinux_shm_shmat(struct shmid_kernel *shp, 5740 char __user *shmaddr, int shmflg) 5741 { 5742 u32 perms; 5743 5744 if (shmflg & SHM_RDONLY) 5745 perms = SHM__READ; 5746 else 5747 perms = SHM__READ | SHM__WRITE; 5748 5749 return ipc_has_perm(&shp->shm_perm, perms); 5750 } 5751 5752 /* Semaphore security operations */ 5753 static int selinux_sem_alloc_security(struct sem_array *sma) 5754 { 5755 struct ipc_security_struct *isec; 5756 struct common_audit_data ad; 5757 u32 sid = current_sid(); 5758 int rc; 5759 5760 rc = ipc_alloc_security(current, &sma->sem_perm, SECCLASS_SEM); 5761 if (rc) 5762 return rc; 5763 5764 isec = sma->sem_perm.security; 5765 5766 ad.type = LSM_AUDIT_DATA_IPC; 5767 ad.u.ipc_id = sma->sem_perm.key; 5768 5769 rc = avc_has_perm(sid, isec->sid, SECCLASS_SEM, 5770 SEM__CREATE, &ad); 5771 if (rc) { 5772 ipc_free_security(&sma->sem_perm); 5773 return rc; 5774 } 5775 return 0; 5776 } 5777 5778 static void selinux_sem_free_security(struct sem_array *sma) 5779 { 5780 ipc_free_security(&sma->sem_perm); 5781 } 5782 5783 static int selinux_sem_associate(struct sem_array *sma, int semflg) 5784 { 5785 struct ipc_security_struct *isec; 5786 struct common_audit_data ad; 5787 u32 sid = current_sid(); 5788 5789 isec = sma->sem_perm.security; 5790 5791 ad.type = LSM_AUDIT_DATA_IPC; 5792 ad.u.ipc_id = sma->sem_perm.key; 5793 5794 return avc_has_perm(sid, isec->sid, SECCLASS_SEM, 5795 SEM__ASSOCIATE, &ad); 5796 } 5797 5798 /* Note, at this point, sma is locked down */ 5799 static int selinux_sem_semctl(struct sem_array *sma, int cmd) 5800 { 5801 int err; 5802 u32 perms; 5803 5804 switch (cmd) { 5805 case IPC_INFO: 5806 case SEM_INFO: 5807 /* No specific object, just general system-wide information. */ 5808 return task_has_system(current, SYSTEM__IPC_INFO); 5809 case GETPID: 5810 case GETNCNT: 5811 case GETZCNT: 5812 perms = SEM__GETATTR; 5813 break; 5814 case GETVAL: 5815 case GETALL: 5816 perms = SEM__READ; 5817 break; 5818 case SETVAL: 5819 case SETALL: 5820 perms = SEM__WRITE; 5821 break; 5822 case IPC_RMID: 5823 perms = SEM__DESTROY; 5824 break; 5825 case IPC_SET: 5826 perms = SEM__SETATTR; 5827 break; 5828 case IPC_STAT: 5829 case SEM_STAT: 5830 perms = SEM__GETATTR | SEM__ASSOCIATE; 5831 break; 5832 default: 5833 return 0; 5834 } 5835 5836 err = ipc_has_perm(&sma->sem_perm, perms); 5837 return err; 5838 } 5839 5840 static int selinux_sem_semop(struct sem_array *sma, 5841 struct sembuf *sops, unsigned nsops, int alter) 5842 { 5843 u32 perms; 5844 5845 if (alter) 5846 perms = SEM__READ | SEM__WRITE; 5847 else 5848 perms = SEM__READ; 5849 5850 return ipc_has_perm(&sma->sem_perm, perms); 5851 } 5852 5853 static int selinux_ipc_permission(struct kern_ipc_perm *ipcp, short flag) 5854 { 5855 u32 av = 0; 5856 5857 av = 0; 5858 if (flag & S_IRUGO) 5859 av |= IPC__UNIX_READ; 5860 if (flag & S_IWUGO) 5861 av |= IPC__UNIX_WRITE; 5862 5863 if (av == 0) 5864 return 0; 5865 5866 return ipc_has_perm(ipcp, av); 5867 } 5868 5869 static void selinux_ipc_getsecid(struct kern_ipc_perm *ipcp, u32 *secid) 5870 { 5871 struct ipc_security_struct *isec = ipcp->security; 5872 *secid = isec->sid; 5873 } 5874 5875 static void selinux_d_instantiate(struct dentry *dentry, struct inode *inode) 5876 { 5877 if (inode) 5878 inode_doinit_with_dentry(inode, dentry); 5879 } 5880 5881 static int selinux_getprocattr(struct task_struct *p, 5882 char *name, char **value) 5883 { 5884 const struct task_security_struct *__tsec; 5885 u32 sid; 5886 int error; 5887 unsigned len; 5888 5889 if (current != p) { 5890 error = current_has_perm(p, PROCESS__GETATTR); 5891 if (error) 5892 return error; 5893 } 5894 5895 rcu_read_lock(); 5896 __tsec = __task_cred(p)->security; 5897 5898 if (!strcmp(name, "current")) 5899 sid = __tsec->sid; 5900 else if (!strcmp(name, "prev")) 5901 sid = __tsec->osid; 5902 else if (!strcmp(name, "exec")) 5903 sid = __tsec->exec_sid; 5904 else if (!strcmp(name, "fscreate")) 5905 sid = __tsec->create_sid; 5906 else if (!strcmp(name, "keycreate")) 5907 sid = __tsec->keycreate_sid; 5908 else if (!strcmp(name, "sockcreate")) 5909 sid = __tsec->sockcreate_sid; 5910 else 5911 goto invalid; 5912 rcu_read_unlock(); 5913 5914 if (!sid) 5915 return 0; 5916 5917 error = security_sid_to_context(sid, value, &len); 5918 if (error) 5919 return error; 5920 return len; 5921 5922 invalid: 5923 rcu_read_unlock(); 5924 return -EINVAL; 5925 } 5926 5927 static int selinux_setprocattr(struct task_struct *p, 5928 char *name, void *value, size_t size) 5929 { 5930 struct task_security_struct *tsec; 5931 struct cred *new; 5932 u32 sid = 0, ptsid; 5933 int error; 5934 char *str = value; 5935 5936 if (current != p) { 5937 /* SELinux only allows a process to change its own 5938 security attributes. */ 5939 return -EACCES; 5940 } 5941 5942 /* 5943 * Basic control over ability to set these attributes at all. 5944 * current == p, but we'll pass them separately in case the 5945 * above restriction is ever removed. 5946 */ 5947 if (!strcmp(name, "exec")) 5948 error = current_has_perm(p, PROCESS__SETEXEC); 5949 else if (!strcmp(name, "fscreate")) 5950 error = current_has_perm(p, PROCESS__SETFSCREATE); 5951 else if (!strcmp(name, "keycreate")) 5952 error = current_has_perm(p, PROCESS__SETKEYCREATE); 5953 else if (!strcmp(name, "sockcreate")) 5954 error = current_has_perm(p, PROCESS__SETSOCKCREATE); 5955 else if (!strcmp(name, "current")) 5956 error = current_has_perm(p, PROCESS__SETCURRENT); 5957 else 5958 error = -EINVAL; 5959 if (error) 5960 return error; 5961 5962 /* Obtain a SID for the context, if one was specified. */ 5963 if (size && str[1] && str[1] != '\n') { 5964 if (str[size-1] == '\n') { 5965 str[size-1] = 0; 5966 size--; 5967 } 5968 error = security_context_to_sid(value, size, &sid, GFP_KERNEL); 5969 if (error == -EINVAL && !strcmp(name, "fscreate")) { 5970 if (!capable(CAP_MAC_ADMIN)) { 5971 struct audit_buffer *ab; 5972 size_t audit_size; 5973 5974 /* We strip a nul only if it is at the end, otherwise the 5975 * context contains a nul and we should audit that */ 5976 if (str[size - 1] == '\0') 5977 audit_size = size - 1; 5978 else 5979 audit_size = size; 5980 ab = audit_log_start(current->audit_context, GFP_ATOMIC, AUDIT_SELINUX_ERR); 5981 audit_log_format(ab, "op=fscreate invalid_context="); 5982 audit_log_n_untrustedstring(ab, value, audit_size); 5983 audit_log_end(ab); 5984 5985 return error; 5986 } 5987 error = security_context_to_sid_force(value, size, 5988 &sid); 5989 } 5990 if (error) 5991 return error; 5992 } 5993 5994 new = prepare_creds(); 5995 if (!new) 5996 return -ENOMEM; 5997 5998 /* Permission checking based on the specified context is 5999 performed during the actual operation (execve, 6000 open/mkdir/...), when we know the full context of the 6001 operation. See selinux_bprm_set_creds for the execve 6002 checks and may_create for the file creation checks. The 6003 operation will then fail if the context is not permitted. */ 6004 tsec = new->security; 6005 if (!strcmp(name, "exec")) { 6006 tsec->exec_sid = sid; 6007 } else if (!strcmp(name, "fscreate")) { 6008 tsec->create_sid = sid; 6009 } else if (!strcmp(name, "keycreate")) { 6010 error = may_create_key(sid, p); 6011 if (error) 6012 goto abort_change; 6013 tsec->keycreate_sid = sid; 6014 } else if (!strcmp(name, "sockcreate")) { 6015 tsec->sockcreate_sid = sid; 6016 } else if (!strcmp(name, "current")) { 6017 error = -EINVAL; 6018 if (sid == 0) 6019 goto abort_change; 6020 6021 /* Only allow single threaded processes to change context */ 6022 error = -EPERM; 6023 if (!current_is_single_threaded()) { 6024 error = security_bounded_transition(tsec->sid, sid); 6025 if (error) 6026 goto abort_change; 6027 } 6028 6029 /* Check permissions for the transition. */ 6030 error = avc_has_perm(tsec->sid, sid, SECCLASS_PROCESS, 6031 PROCESS__DYNTRANSITION, NULL); 6032 if (error) 6033 goto abort_change; 6034 6035 /* Check for ptracing, and update the task SID if ok. 6036 Otherwise, leave SID unchanged and fail. */ 6037 ptsid = ptrace_parent_sid(p); 6038 if (ptsid != 0) { 6039 error = avc_has_perm(ptsid, sid, SECCLASS_PROCESS, 6040 PROCESS__PTRACE, NULL); 6041 if (error) 6042 goto abort_change; 6043 } 6044 6045 tsec->sid = sid; 6046 } else { 6047 error = -EINVAL; 6048 goto abort_change; 6049 } 6050 6051 commit_creds(new); 6052 return size; 6053 6054 abort_change: 6055 abort_creds(new); 6056 return error; 6057 } 6058 6059 static int selinux_ismaclabel(const char *name) 6060 { 6061 return (strcmp(name, XATTR_SELINUX_SUFFIX) == 0); 6062 } 6063 6064 static int selinux_secid_to_secctx(u32 secid, char **secdata, u32 *seclen) 6065 { 6066 return security_sid_to_context(secid, secdata, seclen); 6067 } 6068 6069 static int selinux_secctx_to_secid(const char *secdata, u32 seclen, u32 *secid) 6070 { 6071 return security_context_to_sid(secdata, seclen, secid, GFP_KERNEL); 6072 } 6073 6074 static void selinux_release_secctx(char *secdata, u32 seclen) 6075 { 6076 kfree(secdata); 6077 } 6078 6079 static void selinux_inode_invalidate_secctx(struct inode *inode) 6080 { 6081 struct inode_security_struct *isec = inode->i_security; 6082 6083 spin_lock(&isec->lock); 6084 isec->initialized = LABEL_INVALID; 6085 spin_unlock(&isec->lock); 6086 } 6087 6088 /* 6089 * called with inode->i_mutex locked 6090 */ 6091 static int selinux_inode_notifysecctx(struct inode *inode, void *ctx, u32 ctxlen) 6092 { 6093 return selinux_inode_setsecurity(inode, XATTR_SELINUX_SUFFIX, ctx, ctxlen, 0); 6094 } 6095 6096 /* 6097 * called with inode->i_mutex locked 6098 */ 6099 static int selinux_inode_setsecctx(struct dentry *dentry, void *ctx, u32 ctxlen) 6100 { 6101 return __vfs_setxattr_noperm(dentry, XATTR_NAME_SELINUX, ctx, ctxlen, 0); 6102 } 6103 6104 static int selinux_inode_getsecctx(struct inode *inode, void **ctx, u32 *ctxlen) 6105 { 6106 int len = 0; 6107 len = selinux_inode_getsecurity(inode, XATTR_SELINUX_SUFFIX, 6108 ctx, true); 6109 if (len < 0) 6110 return len; 6111 *ctxlen = len; 6112 return 0; 6113 } 6114 #ifdef CONFIG_KEYS 6115 6116 static int selinux_key_alloc(struct key *k, const struct cred *cred, 6117 unsigned long flags) 6118 { 6119 const struct task_security_struct *tsec; 6120 struct key_security_struct *ksec; 6121 6122 ksec = kzalloc(sizeof(struct key_security_struct), GFP_KERNEL); 6123 if (!ksec) 6124 return -ENOMEM; 6125 6126 tsec = cred->security; 6127 if (tsec->keycreate_sid) 6128 ksec->sid = tsec->keycreate_sid; 6129 else 6130 ksec->sid = tsec->sid; 6131 6132 k->security = ksec; 6133 return 0; 6134 } 6135 6136 static void selinux_key_free(struct key *k) 6137 { 6138 struct key_security_struct *ksec = k->security; 6139 6140 k->security = NULL; 6141 kfree(ksec); 6142 } 6143 6144 static int selinux_key_permission(key_ref_t key_ref, 6145 const struct cred *cred, 6146 unsigned perm) 6147 { 6148 struct key *key; 6149 struct key_security_struct *ksec; 6150 u32 sid; 6151 6152 /* if no specific permissions are requested, we skip the 6153 permission check. No serious, additional covert channels 6154 appear to be created. */ 6155 if (perm == 0) 6156 return 0; 6157 6158 sid = cred_sid(cred); 6159 6160 key = key_ref_to_ptr(key_ref); 6161 ksec = key->security; 6162 6163 return avc_has_perm(sid, ksec->sid, SECCLASS_KEY, perm, NULL); 6164 } 6165 6166 static int selinux_key_getsecurity(struct key *key, char **_buffer) 6167 { 6168 struct key_security_struct *ksec = key->security; 6169 char *context = NULL; 6170 unsigned len; 6171 int rc; 6172 6173 rc = security_sid_to_context(ksec->sid, &context, &len); 6174 if (!rc) 6175 rc = len; 6176 *_buffer = context; 6177 return rc; 6178 } 6179 6180 #endif 6181 6182 static struct security_hook_list selinux_hooks[] = { 6183 LSM_HOOK_INIT(binder_set_context_mgr, selinux_binder_set_context_mgr), 6184 LSM_HOOK_INIT(binder_transaction, selinux_binder_transaction), 6185 LSM_HOOK_INIT(binder_transfer_binder, selinux_binder_transfer_binder), 6186 LSM_HOOK_INIT(binder_transfer_file, selinux_binder_transfer_file), 6187 6188 LSM_HOOK_INIT(ptrace_access_check, selinux_ptrace_access_check), 6189 LSM_HOOK_INIT(ptrace_traceme, selinux_ptrace_traceme), 6190 LSM_HOOK_INIT(capget, selinux_capget), 6191 LSM_HOOK_INIT(capset, selinux_capset), 6192 LSM_HOOK_INIT(capable, selinux_capable), 6193 LSM_HOOK_INIT(quotactl, selinux_quotactl), 6194 LSM_HOOK_INIT(quota_on, selinux_quota_on), 6195 LSM_HOOK_INIT(syslog, selinux_syslog), 6196 LSM_HOOK_INIT(vm_enough_memory, selinux_vm_enough_memory), 6197 6198 LSM_HOOK_INIT(netlink_send, selinux_netlink_send), 6199 6200 LSM_HOOK_INIT(bprm_set_creds, selinux_bprm_set_creds), 6201 LSM_HOOK_INIT(bprm_committing_creds, selinux_bprm_committing_creds), 6202 LSM_HOOK_INIT(bprm_committed_creds, selinux_bprm_committed_creds), 6203 LSM_HOOK_INIT(bprm_secureexec, selinux_bprm_secureexec), 6204 6205 LSM_HOOK_INIT(sb_alloc_security, selinux_sb_alloc_security), 6206 LSM_HOOK_INIT(sb_free_security, selinux_sb_free_security), 6207 LSM_HOOK_INIT(sb_copy_data, selinux_sb_copy_data), 6208 LSM_HOOK_INIT(sb_remount, selinux_sb_remount), 6209 LSM_HOOK_INIT(sb_kern_mount, selinux_sb_kern_mount), 6210 LSM_HOOK_INIT(sb_show_options, selinux_sb_show_options), 6211 LSM_HOOK_INIT(sb_statfs, selinux_sb_statfs), 6212 LSM_HOOK_INIT(sb_mount, selinux_mount), 6213 LSM_HOOK_INIT(sb_umount, selinux_umount), 6214 LSM_HOOK_INIT(sb_set_mnt_opts, selinux_set_mnt_opts), 6215 LSM_HOOK_INIT(sb_clone_mnt_opts, selinux_sb_clone_mnt_opts), 6216 LSM_HOOK_INIT(sb_parse_opts_str, selinux_parse_opts_str), 6217 6218 LSM_HOOK_INIT(dentry_init_security, selinux_dentry_init_security), 6219 LSM_HOOK_INIT(dentry_create_files_as, selinux_dentry_create_files_as), 6220 6221 LSM_HOOK_INIT(inode_alloc_security, selinux_inode_alloc_security), 6222 LSM_HOOK_INIT(inode_free_security, selinux_inode_free_security), 6223 LSM_HOOK_INIT(inode_init_security, selinux_inode_init_security), 6224 LSM_HOOK_INIT(inode_create, selinux_inode_create), 6225 LSM_HOOK_INIT(inode_link, selinux_inode_link), 6226 LSM_HOOK_INIT(inode_unlink, selinux_inode_unlink), 6227 LSM_HOOK_INIT(inode_symlink, selinux_inode_symlink), 6228 LSM_HOOK_INIT(inode_mkdir, selinux_inode_mkdir), 6229 LSM_HOOK_INIT(inode_rmdir, selinux_inode_rmdir), 6230 LSM_HOOK_INIT(inode_mknod, selinux_inode_mknod), 6231 LSM_HOOK_INIT(inode_rename, selinux_inode_rename), 6232 LSM_HOOK_INIT(inode_readlink, selinux_inode_readlink), 6233 LSM_HOOK_INIT(inode_follow_link, selinux_inode_follow_link), 6234 LSM_HOOK_INIT(inode_permission, selinux_inode_permission), 6235 LSM_HOOK_INIT(inode_setattr, selinux_inode_setattr), 6236 LSM_HOOK_INIT(inode_getattr, selinux_inode_getattr), 6237 LSM_HOOK_INIT(inode_setxattr, selinux_inode_setxattr), 6238 LSM_HOOK_INIT(inode_post_setxattr, selinux_inode_post_setxattr), 6239 LSM_HOOK_INIT(inode_getxattr, selinux_inode_getxattr), 6240 LSM_HOOK_INIT(inode_listxattr, selinux_inode_listxattr), 6241 LSM_HOOK_INIT(inode_removexattr, selinux_inode_removexattr), 6242 LSM_HOOK_INIT(inode_getsecurity, selinux_inode_getsecurity), 6243 LSM_HOOK_INIT(inode_setsecurity, selinux_inode_setsecurity), 6244 LSM_HOOK_INIT(inode_listsecurity, selinux_inode_listsecurity), 6245 LSM_HOOK_INIT(inode_getsecid, selinux_inode_getsecid), 6246 LSM_HOOK_INIT(inode_copy_up, selinux_inode_copy_up), 6247 LSM_HOOK_INIT(inode_copy_up_xattr, selinux_inode_copy_up_xattr), 6248 6249 LSM_HOOK_INIT(file_permission, selinux_file_permission), 6250 LSM_HOOK_INIT(file_alloc_security, selinux_file_alloc_security), 6251 LSM_HOOK_INIT(file_free_security, selinux_file_free_security), 6252 LSM_HOOK_INIT(file_ioctl, selinux_file_ioctl), 6253 LSM_HOOK_INIT(mmap_file, selinux_mmap_file), 6254 LSM_HOOK_INIT(mmap_addr, selinux_mmap_addr), 6255 LSM_HOOK_INIT(file_mprotect, selinux_file_mprotect), 6256 LSM_HOOK_INIT(file_lock, selinux_file_lock), 6257 LSM_HOOK_INIT(file_fcntl, selinux_file_fcntl), 6258 LSM_HOOK_INIT(file_set_fowner, selinux_file_set_fowner), 6259 LSM_HOOK_INIT(file_send_sigiotask, selinux_file_send_sigiotask), 6260 LSM_HOOK_INIT(file_receive, selinux_file_receive), 6261 6262 LSM_HOOK_INIT(file_open, selinux_file_open), 6263 6264 LSM_HOOK_INIT(task_create, selinux_task_create), 6265 LSM_HOOK_INIT(cred_alloc_blank, selinux_cred_alloc_blank), 6266 LSM_HOOK_INIT(cred_free, selinux_cred_free), 6267 LSM_HOOK_INIT(cred_prepare, selinux_cred_prepare), 6268 LSM_HOOK_INIT(cred_transfer, selinux_cred_transfer), 6269 LSM_HOOK_INIT(kernel_act_as, selinux_kernel_act_as), 6270 LSM_HOOK_INIT(kernel_create_files_as, selinux_kernel_create_files_as), 6271 LSM_HOOK_INIT(kernel_module_request, selinux_kernel_module_request), 6272 LSM_HOOK_INIT(kernel_read_file, selinux_kernel_read_file), 6273 LSM_HOOK_INIT(task_setpgid, selinux_task_setpgid), 6274 LSM_HOOK_INIT(task_getpgid, selinux_task_getpgid), 6275 LSM_HOOK_INIT(task_getsid, selinux_task_getsid), 6276 LSM_HOOK_INIT(task_getsecid, selinux_task_getsecid), 6277 LSM_HOOK_INIT(task_setnice, selinux_task_setnice), 6278 LSM_HOOK_INIT(task_setioprio, selinux_task_setioprio), 6279 LSM_HOOK_INIT(task_getioprio, selinux_task_getioprio), 6280 LSM_HOOK_INIT(task_setrlimit, selinux_task_setrlimit), 6281 LSM_HOOK_INIT(task_setscheduler, selinux_task_setscheduler), 6282 LSM_HOOK_INIT(task_getscheduler, selinux_task_getscheduler), 6283 LSM_HOOK_INIT(task_movememory, selinux_task_movememory), 6284 LSM_HOOK_INIT(task_kill, selinux_task_kill), 6285 LSM_HOOK_INIT(task_wait, selinux_task_wait), 6286 LSM_HOOK_INIT(task_to_inode, selinux_task_to_inode), 6287 6288 LSM_HOOK_INIT(ipc_permission, selinux_ipc_permission), 6289 LSM_HOOK_INIT(ipc_getsecid, selinux_ipc_getsecid), 6290 6291 LSM_HOOK_INIT(msg_msg_alloc_security, selinux_msg_msg_alloc_security), 6292 LSM_HOOK_INIT(msg_msg_free_security, selinux_msg_msg_free_security), 6293 6294 LSM_HOOK_INIT(msg_queue_alloc_security, 6295 selinux_msg_queue_alloc_security), 6296 LSM_HOOK_INIT(msg_queue_free_security, selinux_msg_queue_free_security), 6297 LSM_HOOK_INIT(msg_queue_associate, selinux_msg_queue_associate), 6298 LSM_HOOK_INIT(msg_queue_msgctl, selinux_msg_queue_msgctl), 6299 LSM_HOOK_INIT(msg_queue_msgsnd, selinux_msg_queue_msgsnd), 6300 LSM_HOOK_INIT(msg_queue_msgrcv, selinux_msg_queue_msgrcv), 6301 6302 LSM_HOOK_INIT(shm_alloc_security, selinux_shm_alloc_security), 6303 LSM_HOOK_INIT(shm_free_security, selinux_shm_free_security), 6304 LSM_HOOK_INIT(shm_associate, selinux_shm_associate), 6305 LSM_HOOK_INIT(shm_shmctl, selinux_shm_shmctl), 6306 LSM_HOOK_INIT(shm_shmat, selinux_shm_shmat), 6307 6308 LSM_HOOK_INIT(sem_alloc_security, selinux_sem_alloc_security), 6309 LSM_HOOK_INIT(sem_free_security, selinux_sem_free_security), 6310 LSM_HOOK_INIT(sem_associate, selinux_sem_associate), 6311 LSM_HOOK_INIT(sem_semctl, selinux_sem_semctl), 6312 LSM_HOOK_INIT(sem_semop, selinux_sem_semop), 6313 6314 LSM_HOOK_INIT(d_instantiate, selinux_d_instantiate), 6315 6316 LSM_HOOK_INIT(getprocattr, selinux_getprocattr), 6317 LSM_HOOK_INIT(setprocattr, selinux_setprocattr), 6318 6319 LSM_HOOK_INIT(ismaclabel, selinux_ismaclabel), 6320 LSM_HOOK_INIT(secid_to_secctx, selinux_secid_to_secctx), 6321 LSM_HOOK_INIT(secctx_to_secid, selinux_secctx_to_secid), 6322 LSM_HOOK_INIT(release_secctx, selinux_release_secctx), 6323 LSM_HOOK_INIT(inode_invalidate_secctx, selinux_inode_invalidate_secctx), 6324 LSM_HOOK_INIT(inode_notifysecctx, selinux_inode_notifysecctx), 6325 LSM_HOOK_INIT(inode_setsecctx, selinux_inode_setsecctx), 6326 LSM_HOOK_INIT(inode_getsecctx, selinux_inode_getsecctx), 6327 6328 LSM_HOOK_INIT(unix_stream_connect, selinux_socket_unix_stream_connect), 6329 LSM_HOOK_INIT(unix_may_send, selinux_socket_unix_may_send), 6330 6331 LSM_HOOK_INIT(socket_create, selinux_socket_create), 6332 LSM_HOOK_INIT(socket_post_create, selinux_socket_post_create), 6333 LSM_HOOK_INIT(socket_bind, selinux_socket_bind), 6334 LSM_HOOK_INIT(socket_connect, selinux_socket_connect), 6335 LSM_HOOK_INIT(socket_listen, selinux_socket_listen), 6336 LSM_HOOK_INIT(socket_accept, selinux_socket_accept), 6337 LSM_HOOK_INIT(socket_sendmsg, selinux_socket_sendmsg), 6338 LSM_HOOK_INIT(socket_recvmsg, selinux_socket_recvmsg), 6339 LSM_HOOK_INIT(socket_getsockname, selinux_socket_getsockname), 6340 LSM_HOOK_INIT(socket_getpeername, selinux_socket_getpeername), 6341 LSM_HOOK_INIT(socket_getsockopt, selinux_socket_getsockopt), 6342 LSM_HOOK_INIT(socket_setsockopt, selinux_socket_setsockopt), 6343 LSM_HOOK_INIT(socket_shutdown, selinux_socket_shutdown), 6344 LSM_HOOK_INIT(socket_sock_rcv_skb, selinux_socket_sock_rcv_skb), 6345 LSM_HOOK_INIT(socket_getpeersec_stream, 6346 selinux_socket_getpeersec_stream), 6347 LSM_HOOK_INIT(socket_getpeersec_dgram, selinux_socket_getpeersec_dgram), 6348 LSM_HOOK_INIT(sk_alloc_security, selinux_sk_alloc_security), 6349 LSM_HOOK_INIT(sk_free_security, selinux_sk_free_security), 6350 LSM_HOOK_INIT(sk_clone_security, selinux_sk_clone_security), 6351 LSM_HOOK_INIT(sk_getsecid, selinux_sk_getsecid), 6352 LSM_HOOK_INIT(sock_graft, selinux_sock_graft), 6353 LSM_HOOK_INIT(inet_conn_request, selinux_inet_conn_request), 6354 LSM_HOOK_INIT(inet_csk_clone, selinux_inet_csk_clone), 6355 LSM_HOOK_INIT(inet_conn_established, selinux_inet_conn_established), 6356 LSM_HOOK_INIT(secmark_relabel_packet, selinux_secmark_relabel_packet), 6357 LSM_HOOK_INIT(secmark_refcount_inc, selinux_secmark_refcount_inc), 6358 LSM_HOOK_INIT(secmark_refcount_dec, selinux_secmark_refcount_dec), 6359 LSM_HOOK_INIT(req_classify_flow, selinux_req_classify_flow), 6360 LSM_HOOK_INIT(tun_dev_alloc_security, selinux_tun_dev_alloc_security), 6361 LSM_HOOK_INIT(tun_dev_free_security, selinux_tun_dev_free_security), 6362 LSM_HOOK_INIT(tun_dev_create, selinux_tun_dev_create), 6363 LSM_HOOK_INIT(tun_dev_attach_queue, selinux_tun_dev_attach_queue), 6364 LSM_HOOK_INIT(tun_dev_attach, selinux_tun_dev_attach), 6365 LSM_HOOK_INIT(tun_dev_open, selinux_tun_dev_open), 6366 6367 #ifdef CONFIG_SECURITY_NETWORK_XFRM 6368 LSM_HOOK_INIT(xfrm_policy_alloc_security, selinux_xfrm_policy_alloc), 6369 LSM_HOOK_INIT(xfrm_policy_clone_security, selinux_xfrm_policy_clone), 6370 LSM_HOOK_INIT(xfrm_policy_free_security, selinux_xfrm_policy_free), 6371 LSM_HOOK_INIT(xfrm_policy_delete_security, selinux_xfrm_policy_delete), 6372 LSM_HOOK_INIT(xfrm_state_alloc, selinux_xfrm_state_alloc), 6373 LSM_HOOK_INIT(xfrm_state_alloc_acquire, 6374 selinux_xfrm_state_alloc_acquire), 6375 LSM_HOOK_INIT(xfrm_state_free_security, selinux_xfrm_state_free), 6376 LSM_HOOK_INIT(xfrm_state_delete_security, selinux_xfrm_state_delete), 6377 LSM_HOOK_INIT(xfrm_policy_lookup, selinux_xfrm_policy_lookup), 6378 LSM_HOOK_INIT(xfrm_state_pol_flow_match, 6379 selinux_xfrm_state_pol_flow_match), 6380 LSM_HOOK_INIT(xfrm_decode_session, selinux_xfrm_decode_session), 6381 #endif 6382 6383 #ifdef CONFIG_KEYS 6384 LSM_HOOK_INIT(key_alloc, selinux_key_alloc), 6385 LSM_HOOK_INIT(key_free, selinux_key_free), 6386 LSM_HOOK_INIT(key_permission, selinux_key_permission), 6387 LSM_HOOK_INIT(key_getsecurity, selinux_key_getsecurity), 6388 #endif 6389 6390 #ifdef CONFIG_AUDIT 6391 LSM_HOOK_INIT(audit_rule_init, selinux_audit_rule_init), 6392 LSM_HOOK_INIT(audit_rule_known, selinux_audit_rule_known), 6393 LSM_HOOK_INIT(audit_rule_match, selinux_audit_rule_match), 6394 LSM_HOOK_INIT(audit_rule_free, selinux_audit_rule_free), 6395 #endif 6396 }; 6397 6398 static __init int selinux_init(void) 6399 { 6400 if (!security_module_enable("selinux")) { 6401 selinux_enabled = 0; 6402 return 0; 6403 } 6404 6405 if (!selinux_enabled) { 6406 printk(KERN_INFO "SELinux: Disabled at boot.\n"); 6407 return 0; 6408 } 6409 6410 printk(KERN_INFO "SELinux: Initializing.\n"); 6411 6412 /* Set the security state for the initial task. */ 6413 cred_init_security(); 6414 6415 default_noexec = !(VM_DATA_DEFAULT_FLAGS & VM_EXEC); 6416 6417 sel_inode_cache = kmem_cache_create("selinux_inode_security", 6418 sizeof(struct inode_security_struct), 6419 0, SLAB_PANIC, NULL); 6420 file_security_cache = kmem_cache_create("selinux_file_security", 6421 sizeof(struct file_security_struct), 6422 0, SLAB_PANIC, NULL); 6423 avc_init(); 6424 6425 security_add_hooks(selinux_hooks, ARRAY_SIZE(selinux_hooks)); 6426 6427 if (avc_add_callback(selinux_netcache_avc_callback, AVC_CALLBACK_RESET)) 6428 panic("SELinux: Unable to register AVC netcache callback\n"); 6429 6430 if (selinux_enforcing) 6431 printk(KERN_DEBUG "SELinux: Starting in enforcing mode\n"); 6432 else 6433 printk(KERN_DEBUG "SELinux: Starting in permissive mode\n"); 6434 6435 return 0; 6436 } 6437 6438 static void delayed_superblock_init(struct super_block *sb, void *unused) 6439 { 6440 superblock_doinit(sb, NULL); 6441 } 6442 6443 void selinux_complete_init(void) 6444 { 6445 printk(KERN_DEBUG "SELinux: Completing initialization.\n"); 6446 6447 /* Set up any superblocks initialized prior to the policy load. */ 6448 printk(KERN_DEBUG "SELinux: Setting up existing superblocks.\n"); 6449 iterate_supers(delayed_superblock_init, NULL); 6450 } 6451 6452 /* SELinux requires early initialization in order to label 6453 all processes and objects when they are created. */ 6454 security_initcall(selinux_init); 6455 6456 #if defined(CONFIG_NETFILTER) 6457 6458 static struct nf_hook_ops selinux_nf_ops[] = { 6459 { 6460 .hook = selinux_ipv4_postroute, 6461 .pf = NFPROTO_IPV4, 6462 .hooknum = NF_INET_POST_ROUTING, 6463 .priority = NF_IP_PRI_SELINUX_LAST, 6464 }, 6465 { 6466 .hook = selinux_ipv4_forward, 6467 .pf = NFPROTO_IPV4, 6468 .hooknum = NF_INET_FORWARD, 6469 .priority = NF_IP_PRI_SELINUX_FIRST, 6470 }, 6471 { 6472 .hook = selinux_ipv4_output, 6473 .pf = NFPROTO_IPV4, 6474 .hooknum = NF_INET_LOCAL_OUT, 6475 .priority = NF_IP_PRI_SELINUX_FIRST, 6476 }, 6477 #if IS_ENABLED(CONFIG_IPV6) 6478 { 6479 .hook = selinux_ipv6_postroute, 6480 .pf = NFPROTO_IPV6, 6481 .hooknum = NF_INET_POST_ROUTING, 6482 .priority = NF_IP6_PRI_SELINUX_LAST, 6483 }, 6484 { 6485 .hook = selinux_ipv6_forward, 6486 .pf = NFPROTO_IPV6, 6487 .hooknum = NF_INET_FORWARD, 6488 .priority = NF_IP6_PRI_SELINUX_FIRST, 6489 }, 6490 { 6491 .hook = selinux_ipv6_output, 6492 .pf = NFPROTO_IPV6, 6493 .hooknum = NF_INET_LOCAL_OUT, 6494 .priority = NF_IP6_PRI_SELINUX_FIRST, 6495 }, 6496 #endif /* IPV6 */ 6497 }; 6498 6499 static int __init selinux_nf_ip_init(void) 6500 { 6501 int err; 6502 6503 if (!selinux_enabled) 6504 return 0; 6505 6506 printk(KERN_DEBUG "SELinux: Registering netfilter hooks\n"); 6507 6508 err = nf_register_hooks(selinux_nf_ops, ARRAY_SIZE(selinux_nf_ops)); 6509 if (err) 6510 panic("SELinux: nf_register_hooks: error %d\n", err); 6511 6512 return 0; 6513 } 6514 6515 __initcall(selinux_nf_ip_init); 6516 6517 #ifdef CONFIG_SECURITY_SELINUX_DISABLE 6518 static void selinux_nf_ip_exit(void) 6519 { 6520 printk(KERN_DEBUG "SELinux: Unregistering netfilter hooks\n"); 6521 6522 nf_unregister_hooks(selinux_nf_ops, ARRAY_SIZE(selinux_nf_ops)); 6523 } 6524 #endif 6525 6526 #else /* CONFIG_NETFILTER */ 6527 6528 #ifdef CONFIG_SECURITY_SELINUX_DISABLE 6529 #define selinux_nf_ip_exit() 6530 #endif 6531 6532 #endif /* CONFIG_NETFILTER */ 6533 6534 #ifdef CONFIG_SECURITY_SELINUX_DISABLE 6535 static int selinux_disabled; 6536 6537 int selinux_disable(void) 6538 { 6539 if (ss_initialized) { 6540 /* Not permitted after initial policy load. */ 6541 return -EINVAL; 6542 } 6543 6544 if (selinux_disabled) { 6545 /* Only do this once. */ 6546 return -EINVAL; 6547 } 6548 6549 printk(KERN_INFO "SELinux: Disabled at runtime.\n"); 6550 6551 selinux_disabled = 1; 6552 selinux_enabled = 0; 6553 6554 security_delete_hooks(selinux_hooks, ARRAY_SIZE(selinux_hooks)); 6555 6556 /* Try to destroy the avc node cache */ 6557 avc_disable(); 6558 6559 /* Unregister netfilter hooks. */ 6560 selinux_nf_ip_exit(); 6561 6562 /* Unregister selinuxfs. */ 6563 exit_sel_fs(); 6564 6565 return 0; 6566 } 6567 #endif 6568