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.moore@hp.com> 18 * Copyright (C) 2007 Hitachi Software Engineering Co., Ltd. 19 * Yuichi Nakamura <ynakam@hitachisoft.jp> 20 * 21 * This program is free software; you can redistribute it and/or modify 22 * it under the terms of the GNU General Public License version 2, 23 * as published by the Free Software Foundation. 24 */ 25 26 #include <linux/init.h> 27 #include <linux/kd.h> 28 #include <linux/kernel.h> 29 #include <linux/tracehook.h> 30 #include <linux/errno.h> 31 #include <linux/ext2_fs.h> 32 #include <linux/sched.h> 33 #include <linux/security.h> 34 #include <linux/xattr.h> 35 #include <linux/capability.h> 36 #include <linux/unistd.h> 37 #include <linux/mm.h> 38 #include <linux/mman.h> 39 #include <linux/slab.h> 40 #include <linux/pagemap.h> 41 #include <linux/proc_fs.h> 42 #include <linux/swap.h> 43 #include <linux/spinlock.h> 44 #include <linux/syscalls.h> 45 #include <linux/dcache.h> 46 #include <linux/file.h> 47 #include <linux/fdtable.h> 48 #include <linux/namei.h> 49 #include <linux/mount.h> 50 #include <linux/netfilter_ipv4.h> 51 #include <linux/netfilter_ipv6.h> 52 #include <linux/tty.h> 53 #include <net/icmp.h> 54 #include <net/ip.h> /* for local_port_range[] */ 55 #include <net/tcp.h> /* struct or_callable used in sock_rcv_skb */ 56 #include <net/net_namespace.h> 57 #include <net/netlabel.h> 58 #include <linux/uaccess.h> 59 #include <asm/ioctls.h> 60 #include <asm/atomic.h> 61 #include <linux/bitops.h> 62 #include <linux/interrupt.h> 63 #include <linux/netdevice.h> /* for network interface checks */ 64 #include <linux/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 84 #include "avc.h" 85 #include "objsec.h" 86 #include "netif.h" 87 #include "netnode.h" 88 #include "netport.h" 89 #include "xfrm.h" 90 #include "netlabel.h" 91 #include "audit.h" 92 93 #define NUM_SEL_MNT_OPTS 5 94 95 extern int selinux_nlmsg_lookup(u16 sclass, u16 nlmsg_type, u32 *perm); 96 extern struct security_operations *security_ops; 97 98 /* SECMARK reference count */ 99 atomic_t selinux_secmark_refcount = ATOMIC_INIT(0); 100 101 #ifdef CONFIG_SECURITY_SELINUX_DEVELOP 102 int selinux_enforcing; 103 104 static int __init enforcing_setup(char *str) 105 { 106 unsigned long enforcing; 107 if (!strict_strtoul(str, 0, &enforcing)) 108 selinux_enforcing = enforcing ? 1 : 0; 109 return 1; 110 } 111 __setup("enforcing=", enforcing_setup); 112 #endif 113 114 #ifdef CONFIG_SECURITY_SELINUX_BOOTPARAM 115 int selinux_enabled = CONFIG_SECURITY_SELINUX_BOOTPARAM_VALUE; 116 117 static int __init selinux_enabled_setup(char *str) 118 { 119 unsigned long enabled; 120 if (!strict_strtoul(str, 0, &enabled)) 121 selinux_enabled = enabled ? 1 : 0; 122 return 1; 123 } 124 __setup("selinux=", selinux_enabled_setup); 125 #else 126 int selinux_enabled = 1; 127 #endif 128 129 static struct kmem_cache *sel_inode_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. 139 * 140 */ 141 static int selinux_secmark_enabled(void) 142 { 143 return (atomic_read(&selinux_secmark_refcount) > 0); 144 } 145 146 /* 147 * initialise the security for the init task 148 */ 149 static void cred_init_security(void) 150 { 151 struct cred *cred = (struct cred *) current->real_cred; 152 struct task_security_struct *tsec; 153 154 tsec = kzalloc(sizeof(struct task_security_struct), GFP_KERNEL); 155 if (!tsec) 156 panic("SELinux: Failed to initialize initial task.\n"); 157 158 tsec->osid = tsec->sid = SECINITSID_KERNEL; 159 cred->security = tsec; 160 } 161 162 /* 163 * get the security ID of a set of credentials 164 */ 165 static inline u32 cred_sid(const struct cred *cred) 166 { 167 const struct task_security_struct *tsec; 168 169 tsec = cred->security; 170 return tsec->sid; 171 } 172 173 /* 174 * get the objective security ID of a task 175 */ 176 static inline u32 task_sid(const struct task_struct *task) 177 { 178 u32 sid; 179 180 rcu_read_lock(); 181 sid = cred_sid(__task_cred(task)); 182 rcu_read_unlock(); 183 return sid; 184 } 185 186 /* 187 * get the subjective security ID of the current task 188 */ 189 static inline u32 current_sid(void) 190 { 191 const struct task_security_struct *tsec = current_security(); 192 193 return tsec->sid; 194 } 195 196 /* Allocate and free functions for each kind of security blob. */ 197 198 static int inode_alloc_security(struct inode *inode) 199 { 200 struct inode_security_struct *isec; 201 u32 sid = current_sid(); 202 203 isec = kmem_cache_zalloc(sel_inode_cache, GFP_NOFS); 204 if (!isec) 205 return -ENOMEM; 206 207 mutex_init(&isec->lock); 208 INIT_LIST_HEAD(&isec->list); 209 isec->inode = inode; 210 isec->sid = SECINITSID_UNLABELED; 211 isec->sclass = SECCLASS_FILE; 212 isec->task_sid = sid; 213 inode->i_security = isec; 214 215 return 0; 216 } 217 218 static void inode_free_security(struct inode *inode) 219 { 220 struct inode_security_struct *isec = inode->i_security; 221 struct superblock_security_struct *sbsec = inode->i_sb->s_security; 222 223 spin_lock(&sbsec->isec_lock); 224 if (!list_empty(&isec->list)) 225 list_del_init(&isec->list); 226 spin_unlock(&sbsec->isec_lock); 227 228 inode->i_security = NULL; 229 kmem_cache_free(sel_inode_cache, isec); 230 } 231 232 static int file_alloc_security(struct file *file) 233 { 234 struct file_security_struct *fsec; 235 u32 sid = current_sid(); 236 237 fsec = kzalloc(sizeof(struct file_security_struct), GFP_KERNEL); 238 if (!fsec) 239 return -ENOMEM; 240 241 fsec->sid = sid; 242 fsec->fown_sid = sid; 243 file->f_security = fsec; 244 245 return 0; 246 } 247 248 static void file_free_security(struct file *file) 249 { 250 struct file_security_struct *fsec = file->f_security; 251 file->f_security = NULL; 252 kfree(fsec); 253 } 254 255 static int superblock_alloc_security(struct super_block *sb) 256 { 257 struct superblock_security_struct *sbsec; 258 259 sbsec = kzalloc(sizeof(struct superblock_security_struct), GFP_KERNEL); 260 if (!sbsec) 261 return -ENOMEM; 262 263 mutex_init(&sbsec->lock); 264 INIT_LIST_HEAD(&sbsec->isec_head); 265 spin_lock_init(&sbsec->isec_lock); 266 sbsec->sb = sb; 267 sbsec->sid = SECINITSID_UNLABELED; 268 sbsec->def_sid = SECINITSID_FILE; 269 sbsec->mntpoint_sid = SECINITSID_UNLABELED; 270 sb->s_security = sbsec; 271 272 return 0; 273 } 274 275 static void superblock_free_security(struct super_block *sb) 276 { 277 struct superblock_security_struct *sbsec = sb->s_security; 278 sb->s_security = NULL; 279 kfree(sbsec); 280 } 281 282 /* The security server must be initialized before 283 any labeling or access decisions can be provided. */ 284 extern int ss_initialized; 285 286 /* The file system's label must be initialized prior to use. */ 287 288 static const char *labeling_behaviors[6] = { 289 "uses xattr", 290 "uses transition SIDs", 291 "uses task SIDs", 292 "uses genfs_contexts", 293 "not configured for labeling", 294 "uses mountpoint labeling", 295 }; 296 297 static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dentry); 298 299 static inline int inode_doinit(struct inode *inode) 300 { 301 return inode_doinit_with_dentry(inode, NULL); 302 } 303 304 enum { 305 Opt_error = -1, 306 Opt_context = 1, 307 Opt_fscontext = 2, 308 Opt_defcontext = 3, 309 Opt_rootcontext = 4, 310 Opt_labelsupport = 5, 311 }; 312 313 static const match_table_t tokens = { 314 {Opt_context, CONTEXT_STR "%s"}, 315 {Opt_fscontext, FSCONTEXT_STR "%s"}, 316 {Opt_defcontext, DEFCONTEXT_STR "%s"}, 317 {Opt_rootcontext, ROOTCONTEXT_STR "%s"}, 318 {Opt_labelsupport, LABELSUPP_STR}, 319 {Opt_error, NULL}, 320 }; 321 322 #define SEL_MOUNT_FAIL_MSG "SELinux: duplicate or incompatible mount options\n" 323 324 static int may_context_mount_sb_relabel(u32 sid, 325 struct superblock_security_struct *sbsec, 326 const struct cred *cred) 327 { 328 const struct task_security_struct *tsec = cred->security; 329 int rc; 330 331 rc = avc_has_perm(tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM, 332 FILESYSTEM__RELABELFROM, NULL); 333 if (rc) 334 return rc; 335 336 rc = avc_has_perm(tsec->sid, sid, SECCLASS_FILESYSTEM, 337 FILESYSTEM__RELABELTO, NULL); 338 return rc; 339 } 340 341 static int may_context_mount_inode_relabel(u32 sid, 342 struct superblock_security_struct *sbsec, 343 const struct cred *cred) 344 { 345 const struct task_security_struct *tsec = cred->security; 346 int rc; 347 rc = avc_has_perm(tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM, 348 FILESYSTEM__RELABELFROM, NULL); 349 if (rc) 350 return rc; 351 352 rc = avc_has_perm(sid, sbsec->sid, SECCLASS_FILESYSTEM, 353 FILESYSTEM__ASSOCIATE, NULL); 354 return rc; 355 } 356 357 static int sb_finish_set_opts(struct super_block *sb) 358 { 359 struct superblock_security_struct *sbsec = sb->s_security; 360 struct dentry *root = sb->s_root; 361 struct inode *root_inode = root->d_inode; 362 int rc = 0; 363 364 if (sbsec->behavior == SECURITY_FS_USE_XATTR) { 365 /* Make sure that the xattr handler exists and that no 366 error other than -ENODATA is returned by getxattr on 367 the root directory. -ENODATA is ok, as this may be 368 the first boot of the SELinux kernel before we have 369 assigned xattr values to the filesystem. */ 370 if (!root_inode->i_op->getxattr) { 371 printk(KERN_WARNING "SELinux: (dev %s, type %s) has no " 372 "xattr support\n", sb->s_id, sb->s_type->name); 373 rc = -EOPNOTSUPP; 374 goto out; 375 } 376 rc = root_inode->i_op->getxattr(root, XATTR_NAME_SELINUX, NULL, 0); 377 if (rc < 0 && rc != -ENODATA) { 378 if (rc == -EOPNOTSUPP) 379 printk(KERN_WARNING "SELinux: (dev %s, type " 380 "%s) has no security xattr handler\n", 381 sb->s_id, sb->s_type->name); 382 else 383 printk(KERN_WARNING "SELinux: (dev %s, type " 384 "%s) getxattr errno %d\n", sb->s_id, 385 sb->s_type->name, -rc); 386 goto out; 387 } 388 } 389 390 sbsec->flags |= (SE_SBINITIALIZED | SE_SBLABELSUPP); 391 392 if (sbsec->behavior > ARRAY_SIZE(labeling_behaviors)) 393 printk(KERN_ERR "SELinux: initialized (dev %s, type %s), unknown behavior\n", 394 sb->s_id, sb->s_type->name); 395 else 396 printk(KERN_DEBUG "SELinux: initialized (dev %s, type %s), %s\n", 397 sb->s_id, sb->s_type->name, 398 labeling_behaviors[sbsec->behavior-1]); 399 400 if (sbsec->behavior == SECURITY_FS_USE_GENFS || 401 sbsec->behavior == SECURITY_FS_USE_MNTPOINT || 402 sbsec->behavior == SECURITY_FS_USE_NONE || 403 sbsec->behavior > ARRAY_SIZE(labeling_behaviors)) 404 sbsec->flags &= ~SE_SBLABELSUPP; 405 406 /* Special handling for sysfs. Is genfs but also has setxattr handler*/ 407 if (strncmp(sb->s_type->name, "sysfs", sizeof("sysfs")) == 0) 408 sbsec->flags |= SE_SBLABELSUPP; 409 410 /* Initialize the root inode. */ 411 rc = inode_doinit_with_dentry(root_inode, root); 412 413 /* Initialize any other inodes associated with the superblock, e.g. 414 inodes created prior to initial policy load or inodes created 415 during get_sb by a pseudo filesystem that directly 416 populates itself. */ 417 spin_lock(&sbsec->isec_lock); 418 next_inode: 419 if (!list_empty(&sbsec->isec_head)) { 420 struct inode_security_struct *isec = 421 list_entry(sbsec->isec_head.next, 422 struct inode_security_struct, list); 423 struct inode *inode = isec->inode; 424 spin_unlock(&sbsec->isec_lock); 425 inode = igrab(inode); 426 if (inode) { 427 if (!IS_PRIVATE(inode)) 428 inode_doinit(inode); 429 iput(inode); 430 } 431 spin_lock(&sbsec->isec_lock); 432 list_del_init(&isec->list); 433 goto next_inode; 434 } 435 spin_unlock(&sbsec->isec_lock); 436 out: 437 return rc; 438 } 439 440 /* 441 * This function should allow an FS to ask what it's mount security 442 * options were so it can use those later for submounts, displaying 443 * mount options, or whatever. 444 */ 445 static int selinux_get_mnt_opts(const struct super_block *sb, 446 struct security_mnt_opts *opts) 447 { 448 int rc = 0, i; 449 struct superblock_security_struct *sbsec = sb->s_security; 450 char *context = NULL; 451 u32 len; 452 char tmp; 453 454 security_init_mnt_opts(opts); 455 456 if (!(sbsec->flags & SE_SBINITIALIZED)) 457 return -EINVAL; 458 459 if (!ss_initialized) 460 return -EINVAL; 461 462 tmp = sbsec->flags & SE_MNTMASK; 463 /* count the number of mount options for this sb */ 464 for (i = 0; i < 8; i++) { 465 if (tmp & 0x01) 466 opts->num_mnt_opts++; 467 tmp >>= 1; 468 } 469 /* Check if the Label support flag is set */ 470 if (sbsec->flags & SE_SBLABELSUPP) 471 opts->num_mnt_opts++; 472 473 opts->mnt_opts = kcalloc(opts->num_mnt_opts, sizeof(char *), GFP_ATOMIC); 474 if (!opts->mnt_opts) { 475 rc = -ENOMEM; 476 goto out_free; 477 } 478 479 opts->mnt_opts_flags = kcalloc(opts->num_mnt_opts, sizeof(int), GFP_ATOMIC); 480 if (!opts->mnt_opts_flags) { 481 rc = -ENOMEM; 482 goto out_free; 483 } 484 485 i = 0; 486 if (sbsec->flags & FSCONTEXT_MNT) { 487 rc = security_sid_to_context(sbsec->sid, &context, &len); 488 if (rc) 489 goto out_free; 490 opts->mnt_opts[i] = context; 491 opts->mnt_opts_flags[i++] = FSCONTEXT_MNT; 492 } 493 if (sbsec->flags & CONTEXT_MNT) { 494 rc = security_sid_to_context(sbsec->mntpoint_sid, &context, &len); 495 if (rc) 496 goto out_free; 497 opts->mnt_opts[i] = context; 498 opts->mnt_opts_flags[i++] = CONTEXT_MNT; 499 } 500 if (sbsec->flags & DEFCONTEXT_MNT) { 501 rc = security_sid_to_context(sbsec->def_sid, &context, &len); 502 if (rc) 503 goto out_free; 504 opts->mnt_opts[i] = context; 505 opts->mnt_opts_flags[i++] = DEFCONTEXT_MNT; 506 } 507 if (sbsec->flags & ROOTCONTEXT_MNT) { 508 struct inode *root = sbsec->sb->s_root->d_inode; 509 struct inode_security_struct *isec = root->i_security; 510 511 rc = security_sid_to_context(isec->sid, &context, &len); 512 if (rc) 513 goto out_free; 514 opts->mnt_opts[i] = context; 515 opts->mnt_opts_flags[i++] = ROOTCONTEXT_MNT; 516 } 517 if (sbsec->flags & SE_SBLABELSUPP) { 518 opts->mnt_opts[i] = NULL; 519 opts->mnt_opts_flags[i++] = SE_SBLABELSUPP; 520 } 521 522 BUG_ON(i != opts->num_mnt_opts); 523 524 return 0; 525 526 out_free: 527 security_free_mnt_opts(opts); 528 return rc; 529 } 530 531 static int bad_option(struct superblock_security_struct *sbsec, char flag, 532 u32 old_sid, u32 new_sid) 533 { 534 char mnt_flags = sbsec->flags & SE_MNTMASK; 535 536 /* check if the old mount command had the same options */ 537 if (sbsec->flags & SE_SBINITIALIZED) 538 if (!(sbsec->flags & flag) || 539 (old_sid != new_sid)) 540 return 1; 541 542 /* check if we were passed the same options twice, 543 * aka someone passed context=a,context=b 544 */ 545 if (!(sbsec->flags & SE_SBINITIALIZED)) 546 if (mnt_flags & flag) 547 return 1; 548 return 0; 549 } 550 551 /* 552 * Allow filesystems with binary mount data to explicitly set mount point 553 * labeling information. 554 */ 555 static int selinux_set_mnt_opts(struct super_block *sb, 556 struct security_mnt_opts *opts) 557 { 558 const struct cred *cred = current_cred(); 559 int rc = 0, i; 560 struct superblock_security_struct *sbsec = sb->s_security; 561 const char *name = sb->s_type->name; 562 struct inode *inode = sbsec->sb->s_root->d_inode; 563 struct inode_security_struct *root_isec = inode->i_security; 564 u32 fscontext_sid = 0, context_sid = 0, rootcontext_sid = 0; 565 u32 defcontext_sid = 0; 566 char **mount_options = opts->mnt_opts; 567 int *flags = opts->mnt_opts_flags; 568 int num_opts = opts->num_mnt_opts; 569 570 mutex_lock(&sbsec->lock); 571 572 if (!ss_initialized) { 573 if (!num_opts) { 574 /* Defer initialization until selinux_complete_init, 575 after the initial policy is loaded and the security 576 server is ready to handle calls. */ 577 goto out; 578 } 579 rc = -EINVAL; 580 printk(KERN_WARNING "SELinux: Unable to set superblock options " 581 "before the security server is initialized\n"); 582 goto out; 583 } 584 585 /* 586 * Binary mount data FS will come through this function twice. Once 587 * from an explicit call and once from the generic calls from the vfs. 588 * Since the generic VFS calls will not contain any security mount data 589 * we need to skip the double mount verification. 590 * 591 * This does open a hole in which we will not notice if the first 592 * mount using this sb set explict options and a second mount using 593 * this sb does not set any security options. (The first options 594 * will be used for both mounts) 595 */ 596 if ((sbsec->flags & SE_SBINITIALIZED) && (sb->s_type->fs_flags & FS_BINARY_MOUNTDATA) 597 && (num_opts == 0)) 598 goto out; 599 600 /* 601 * parse the mount options, check if they are valid sids. 602 * also check if someone is trying to mount the same sb more 603 * than once with different security options. 604 */ 605 for (i = 0; i < num_opts; i++) { 606 u32 sid; 607 608 if (flags[i] == SE_SBLABELSUPP) 609 continue; 610 rc = security_context_to_sid(mount_options[i], 611 strlen(mount_options[i]), &sid); 612 if (rc) { 613 printk(KERN_WARNING "SELinux: security_context_to_sid" 614 "(%s) failed for (dev %s, type %s) errno=%d\n", 615 mount_options[i], sb->s_id, name, rc); 616 goto out; 617 } 618 switch (flags[i]) { 619 case FSCONTEXT_MNT: 620 fscontext_sid = sid; 621 622 if (bad_option(sbsec, FSCONTEXT_MNT, sbsec->sid, 623 fscontext_sid)) 624 goto out_double_mount; 625 626 sbsec->flags |= FSCONTEXT_MNT; 627 break; 628 case CONTEXT_MNT: 629 context_sid = sid; 630 631 if (bad_option(sbsec, CONTEXT_MNT, sbsec->mntpoint_sid, 632 context_sid)) 633 goto out_double_mount; 634 635 sbsec->flags |= CONTEXT_MNT; 636 break; 637 case ROOTCONTEXT_MNT: 638 rootcontext_sid = sid; 639 640 if (bad_option(sbsec, ROOTCONTEXT_MNT, root_isec->sid, 641 rootcontext_sid)) 642 goto out_double_mount; 643 644 sbsec->flags |= ROOTCONTEXT_MNT; 645 646 break; 647 case DEFCONTEXT_MNT: 648 defcontext_sid = sid; 649 650 if (bad_option(sbsec, DEFCONTEXT_MNT, sbsec->def_sid, 651 defcontext_sid)) 652 goto out_double_mount; 653 654 sbsec->flags |= DEFCONTEXT_MNT; 655 656 break; 657 default: 658 rc = -EINVAL; 659 goto out; 660 } 661 } 662 663 if (sbsec->flags & SE_SBINITIALIZED) { 664 /* previously mounted with options, but not on this attempt? */ 665 if ((sbsec->flags & SE_MNTMASK) && !num_opts) 666 goto out_double_mount; 667 rc = 0; 668 goto out; 669 } 670 671 if (strcmp(sb->s_type->name, "proc") == 0) 672 sbsec->flags |= SE_SBPROC; 673 674 /* Determine the labeling behavior to use for this filesystem type. */ 675 rc = security_fs_use((sbsec->flags & SE_SBPROC) ? "proc" : sb->s_type->name, &sbsec->behavior, &sbsec->sid); 676 if (rc) { 677 printk(KERN_WARNING "%s: security_fs_use(%s) returned %d\n", 678 __func__, sb->s_type->name, rc); 679 goto out; 680 } 681 682 /* sets the context of the superblock for the fs being mounted. */ 683 if (fscontext_sid) { 684 rc = may_context_mount_sb_relabel(fscontext_sid, sbsec, cred); 685 if (rc) 686 goto out; 687 688 sbsec->sid = fscontext_sid; 689 } 690 691 /* 692 * Switch to using mount point labeling behavior. 693 * sets the label used on all file below the mountpoint, and will set 694 * the superblock context if not already set. 695 */ 696 if (context_sid) { 697 if (!fscontext_sid) { 698 rc = may_context_mount_sb_relabel(context_sid, sbsec, 699 cred); 700 if (rc) 701 goto out; 702 sbsec->sid = context_sid; 703 } else { 704 rc = may_context_mount_inode_relabel(context_sid, sbsec, 705 cred); 706 if (rc) 707 goto out; 708 } 709 if (!rootcontext_sid) 710 rootcontext_sid = context_sid; 711 712 sbsec->mntpoint_sid = context_sid; 713 sbsec->behavior = SECURITY_FS_USE_MNTPOINT; 714 } 715 716 if (rootcontext_sid) { 717 rc = may_context_mount_inode_relabel(rootcontext_sid, sbsec, 718 cred); 719 if (rc) 720 goto out; 721 722 root_isec->sid = rootcontext_sid; 723 root_isec->initialized = 1; 724 } 725 726 if (defcontext_sid) { 727 if (sbsec->behavior != SECURITY_FS_USE_XATTR) { 728 rc = -EINVAL; 729 printk(KERN_WARNING "SELinux: defcontext option is " 730 "invalid for this filesystem type\n"); 731 goto out; 732 } 733 734 if (defcontext_sid != sbsec->def_sid) { 735 rc = may_context_mount_inode_relabel(defcontext_sid, 736 sbsec, cred); 737 if (rc) 738 goto out; 739 } 740 741 sbsec->def_sid = defcontext_sid; 742 } 743 744 rc = sb_finish_set_opts(sb); 745 out: 746 mutex_unlock(&sbsec->lock); 747 return rc; 748 out_double_mount: 749 rc = -EINVAL; 750 printk(KERN_WARNING "SELinux: mount invalid. Same superblock, different " 751 "security settings for (dev %s, type %s)\n", sb->s_id, name); 752 goto out; 753 } 754 755 static void selinux_sb_clone_mnt_opts(const struct super_block *oldsb, 756 struct super_block *newsb) 757 { 758 const struct superblock_security_struct *oldsbsec = oldsb->s_security; 759 struct superblock_security_struct *newsbsec = newsb->s_security; 760 761 int set_fscontext = (oldsbsec->flags & FSCONTEXT_MNT); 762 int set_context = (oldsbsec->flags & CONTEXT_MNT); 763 int set_rootcontext = (oldsbsec->flags & ROOTCONTEXT_MNT); 764 765 /* 766 * if the parent was able to be mounted it clearly had no special lsm 767 * mount options. thus we can safely deal with this superblock later 768 */ 769 if (!ss_initialized) 770 return; 771 772 /* how can we clone if the old one wasn't set up?? */ 773 BUG_ON(!(oldsbsec->flags & SE_SBINITIALIZED)); 774 775 /* if fs is reusing a sb, just let its options stand... */ 776 if (newsbsec->flags & SE_SBINITIALIZED) 777 return; 778 779 mutex_lock(&newsbsec->lock); 780 781 newsbsec->flags = oldsbsec->flags; 782 783 newsbsec->sid = oldsbsec->sid; 784 newsbsec->def_sid = oldsbsec->def_sid; 785 newsbsec->behavior = oldsbsec->behavior; 786 787 if (set_context) { 788 u32 sid = oldsbsec->mntpoint_sid; 789 790 if (!set_fscontext) 791 newsbsec->sid = sid; 792 if (!set_rootcontext) { 793 struct inode *newinode = newsb->s_root->d_inode; 794 struct inode_security_struct *newisec = newinode->i_security; 795 newisec->sid = sid; 796 } 797 newsbsec->mntpoint_sid = sid; 798 } 799 if (set_rootcontext) { 800 const struct inode *oldinode = oldsb->s_root->d_inode; 801 const struct inode_security_struct *oldisec = oldinode->i_security; 802 struct inode *newinode = newsb->s_root->d_inode; 803 struct inode_security_struct *newisec = newinode->i_security; 804 805 newisec->sid = oldisec->sid; 806 } 807 808 sb_finish_set_opts(newsb); 809 mutex_unlock(&newsbsec->lock); 810 } 811 812 static int selinux_parse_opts_str(char *options, 813 struct security_mnt_opts *opts) 814 { 815 char *p; 816 char *context = NULL, *defcontext = NULL; 817 char *fscontext = NULL, *rootcontext = NULL; 818 int rc, num_mnt_opts = 0; 819 820 opts->num_mnt_opts = 0; 821 822 /* Standard string-based options. */ 823 while ((p = strsep(&options, "|")) != NULL) { 824 int token; 825 substring_t args[MAX_OPT_ARGS]; 826 827 if (!*p) 828 continue; 829 830 token = match_token(p, tokens, args); 831 832 switch (token) { 833 case Opt_context: 834 if (context || defcontext) { 835 rc = -EINVAL; 836 printk(KERN_WARNING SEL_MOUNT_FAIL_MSG); 837 goto out_err; 838 } 839 context = match_strdup(&args[0]); 840 if (!context) { 841 rc = -ENOMEM; 842 goto out_err; 843 } 844 break; 845 846 case Opt_fscontext: 847 if (fscontext) { 848 rc = -EINVAL; 849 printk(KERN_WARNING SEL_MOUNT_FAIL_MSG); 850 goto out_err; 851 } 852 fscontext = match_strdup(&args[0]); 853 if (!fscontext) { 854 rc = -ENOMEM; 855 goto out_err; 856 } 857 break; 858 859 case Opt_rootcontext: 860 if (rootcontext) { 861 rc = -EINVAL; 862 printk(KERN_WARNING SEL_MOUNT_FAIL_MSG); 863 goto out_err; 864 } 865 rootcontext = match_strdup(&args[0]); 866 if (!rootcontext) { 867 rc = -ENOMEM; 868 goto out_err; 869 } 870 break; 871 872 case Opt_defcontext: 873 if (context || defcontext) { 874 rc = -EINVAL; 875 printk(KERN_WARNING SEL_MOUNT_FAIL_MSG); 876 goto out_err; 877 } 878 defcontext = match_strdup(&args[0]); 879 if (!defcontext) { 880 rc = -ENOMEM; 881 goto out_err; 882 } 883 break; 884 case Opt_labelsupport: 885 break; 886 default: 887 rc = -EINVAL; 888 printk(KERN_WARNING "SELinux: unknown mount option\n"); 889 goto out_err; 890 891 } 892 } 893 894 rc = -ENOMEM; 895 opts->mnt_opts = kcalloc(NUM_SEL_MNT_OPTS, sizeof(char *), GFP_ATOMIC); 896 if (!opts->mnt_opts) 897 goto out_err; 898 899 opts->mnt_opts_flags = kcalloc(NUM_SEL_MNT_OPTS, sizeof(int), GFP_ATOMIC); 900 if (!opts->mnt_opts_flags) { 901 kfree(opts->mnt_opts); 902 goto out_err; 903 } 904 905 if (fscontext) { 906 opts->mnt_opts[num_mnt_opts] = fscontext; 907 opts->mnt_opts_flags[num_mnt_opts++] = FSCONTEXT_MNT; 908 } 909 if (context) { 910 opts->mnt_opts[num_mnt_opts] = context; 911 opts->mnt_opts_flags[num_mnt_opts++] = CONTEXT_MNT; 912 } 913 if (rootcontext) { 914 opts->mnt_opts[num_mnt_opts] = rootcontext; 915 opts->mnt_opts_flags[num_mnt_opts++] = ROOTCONTEXT_MNT; 916 } 917 if (defcontext) { 918 opts->mnt_opts[num_mnt_opts] = defcontext; 919 opts->mnt_opts_flags[num_mnt_opts++] = DEFCONTEXT_MNT; 920 } 921 922 opts->num_mnt_opts = num_mnt_opts; 923 return 0; 924 925 out_err: 926 kfree(context); 927 kfree(defcontext); 928 kfree(fscontext); 929 kfree(rootcontext); 930 return rc; 931 } 932 /* 933 * string mount options parsing and call set the sbsec 934 */ 935 static int superblock_doinit(struct super_block *sb, void *data) 936 { 937 int rc = 0; 938 char *options = data; 939 struct security_mnt_opts opts; 940 941 security_init_mnt_opts(&opts); 942 943 if (!data) 944 goto out; 945 946 BUG_ON(sb->s_type->fs_flags & FS_BINARY_MOUNTDATA); 947 948 rc = selinux_parse_opts_str(options, &opts); 949 if (rc) 950 goto out_err; 951 952 out: 953 rc = selinux_set_mnt_opts(sb, &opts); 954 955 out_err: 956 security_free_mnt_opts(&opts); 957 return rc; 958 } 959 960 static void selinux_write_opts(struct seq_file *m, 961 struct security_mnt_opts *opts) 962 { 963 int i; 964 char *prefix; 965 966 for (i = 0; i < opts->num_mnt_opts; i++) { 967 char *has_comma; 968 969 if (opts->mnt_opts[i]) 970 has_comma = strchr(opts->mnt_opts[i], ','); 971 else 972 has_comma = NULL; 973 974 switch (opts->mnt_opts_flags[i]) { 975 case CONTEXT_MNT: 976 prefix = CONTEXT_STR; 977 break; 978 case FSCONTEXT_MNT: 979 prefix = FSCONTEXT_STR; 980 break; 981 case ROOTCONTEXT_MNT: 982 prefix = ROOTCONTEXT_STR; 983 break; 984 case DEFCONTEXT_MNT: 985 prefix = DEFCONTEXT_STR; 986 break; 987 case SE_SBLABELSUPP: 988 seq_putc(m, ','); 989 seq_puts(m, LABELSUPP_STR); 990 continue; 991 default: 992 BUG(); 993 return; 994 }; 995 /* we need a comma before each option */ 996 seq_putc(m, ','); 997 seq_puts(m, prefix); 998 if (has_comma) 999 seq_putc(m, '\"'); 1000 seq_puts(m, opts->mnt_opts[i]); 1001 if (has_comma) 1002 seq_putc(m, '\"'); 1003 } 1004 } 1005 1006 static int selinux_sb_show_options(struct seq_file *m, struct super_block *sb) 1007 { 1008 struct security_mnt_opts opts; 1009 int rc; 1010 1011 rc = selinux_get_mnt_opts(sb, &opts); 1012 if (rc) { 1013 /* before policy load we may get EINVAL, don't show anything */ 1014 if (rc == -EINVAL) 1015 rc = 0; 1016 return rc; 1017 } 1018 1019 selinux_write_opts(m, &opts); 1020 1021 security_free_mnt_opts(&opts); 1022 1023 return rc; 1024 } 1025 1026 static inline u16 inode_mode_to_security_class(umode_t mode) 1027 { 1028 switch (mode & S_IFMT) { 1029 case S_IFSOCK: 1030 return SECCLASS_SOCK_FILE; 1031 case S_IFLNK: 1032 return SECCLASS_LNK_FILE; 1033 case S_IFREG: 1034 return SECCLASS_FILE; 1035 case S_IFBLK: 1036 return SECCLASS_BLK_FILE; 1037 case S_IFDIR: 1038 return SECCLASS_DIR; 1039 case S_IFCHR: 1040 return SECCLASS_CHR_FILE; 1041 case S_IFIFO: 1042 return SECCLASS_FIFO_FILE; 1043 1044 } 1045 1046 return SECCLASS_FILE; 1047 } 1048 1049 static inline int default_protocol_stream(int protocol) 1050 { 1051 return (protocol == IPPROTO_IP || protocol == IPPROTO_TCP); 1052 } 1053 1054 static inline int default_protocol_dgram(int protocol) 1055 { 1056 return (protocol == IPPROTO_IP || protocol == IPPROTO_UDP); 1057 } 1058 1059 static inline u16 socket_type_to_security_class(int family, int type, int protocol) 1060 { 1061 switch (family) { 1062 case PF_UNIX: 1063 switch (type) { 1064 case SOCK_STREAM: 1065 case SOCK_SEQPACKET: 1066 return SECCLASS_UNIX_STREAM_SOCKET; 1067 case SOCK_DGRAM: 1068 return SECCLASS_UNIX_DGRAM_SOCKET; 1069 } 1070 break; 1071 case PF_INET: 1072 case PF_INET6: 1073 switch (type) { 1074 case SOCK_STREAM: 1075 if (default_protocol_stream(protocol)) 1076 return SECCLASS_TCP_SOCKET; 1077 else 1078 return SECCLASS_RAWIP_SOCKET; 1079 case SOCK_DGRAM: 1080 if (default_protocol_dgram(protocol)) 1081 return SECCLASS_UDP_SOCKET; 1082 else 1083 return SECCLASS_RAWIP_SOCKET; 1084 case SOCK_DCCP: 1085 return SECCLASS_DCCP_SOCKET; 1086 default: 1087 return SECCLASS_RAWIP_SOCKET; 1088 } 1089 break; 1090 case PF_NETLINK: 1091 switch (protocol) { 1092 case NETLINK_ROUTE: 1093 return SECCLASS_NETLINK_ROUTE_SOCKET; 1094 case NETLINK_FIREWALL: 1095 return SECCLASS_NETLINK_FIREWALL_SOCKET; 1096 case NETLINK_INET_DIAG: 1097 return SECCLASS_NETLINK_TCPDIAG_SOCKET; 1098 case NETLINK_NFLOG: 1099 return SECCLASS_NETLINK_NFLOG_SOCKET; 1100 case NETLINK_XFRM: 1101 return SECCLASS_NETLINK_XFRM_SOCKET; 1102 case NETLINK_SELINUX: 1103 return SECCLASS_NETLINK_SELINUX_SOCKET; 1104 case NETLINK_AUDIT: 1105 return SECCLASS_NETLINK_AUDIT_SOCKET; 1106 case NETLINK_IP6_FW: 1107 return SECCLASS_NETLINK_IP6FW_SOCKET; 1108 case NETLINK_DNRTMSG: 1109 return SECCLASS_NETLINK_DNRT_SOCKET; 1110 case NETLINK_KOBJECT_UEVENT: 1111 return SECCLASS_NETLINK_KOBJECT_UEVENT_SOCKET; 1112 default: 1113 return SECCLASS_NETLINK_SOCKET; 1114 } 1115 case PF_PACKET: 1116 return SECCLASS_PACKET_SOCKET; 1117 case PF_KEY: 1118 return SECCLASS_KEY_SOCKET; 1119 case PF_APPLETALK: 1120 return SECCLASS_APPLETALK_SOCKET; 1121 } 1122 1123 return SECCLASS_SOCKET; 1124 } 1125 1126 #ifdef CONFIG_PROC_FS 1127 static int selinux_proc_get_sid(struct dentry *dentry, 1128 u16 tclass, 1129 u32 *sid) 1130 { 1131 int rc; 1132 char *buffer, *path; 1133 1134 buffer = (char *)__get_free_page(GFP_KERNEL); 1135 if (!buffer) 1136 return -ENOMEM; 1137 1138 path = dentry_path_raw(dentry, buffer, PAGE_SIZE); 1139 if (IS_ERR(path)) 1140 rc = PTR_ERR(path); 1141 else { 1142 /* each process gets a /proc/PID/ entry. Strip off the 1143 * PID part to get a valid selinux labeling. 1144 * e.g. /proc/1/net/rpc/nfs -> /net/rpc/nfs */ 1145 while (path[1] >= '0' && path[1] <= '9') { 1146 path[1] = '/'; 1147 path++; 1148 } 1149 rc = security_genfs_sid("proc", path, tclass, sid); 1150 } 1151 free_page((unsigned long)buffer); 1152 return rc; 1153 } 1154 #else 1155 static int selinux_proc_get_sid(struct dentry *dentry, 1156 u16 tclass, 1157 u32 *sid) 1158 { 1159 return -EINVAL; 1160 } 1161 #endif 1162 1163 /* The inode's security attributes must be initialized before first use. */ 1164 static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dentry) 1165 { 1166 struct superblock_security_struct *sbsec = NULL; 1167 struct inode_security_struct *isec = inode->i_security; 1168 u32 sid; 1169 struct dentry *dentry; 1170 #define INITCONTEXTLEN 255 1171 char *context = NULL; 1172 unsigned len = 0; 1173 int rc = 0; 1174 1175 if (isec->initialized) 1176 goto out; 1177 1178 mutex_lock(&isec->lock); 1179 if (isec->initialized) 1180 goto out_unlock; 1181 1182 sbsec = inode->i_sb->s_security; 1183 if (!(sbsec->flags & SE_SBINITIALIZED)) { 1184 /* Defer initialization until selinux_complete_init, 1185 after the initial policy is loaded and the security 1186 server is ready to handle calls. */ 1187 spin_lock(&sbsec->isec_lock); 1188 if (list_empty(&isec->list)) 1189 list_add(&isec->list, &sbsec->isec_head); 1190 spin_unlock(&sbsec->isec_lock); 1191 goto out_unlock; 1192 } 1193 1194 switch (sbsec->behavior) { 1195 case SECURITY_FS_USE_XATTR: 1196 if (!inode->i_op->getxattr) { 1197 isec->sid = sbsec->def_sid; 1198 break; 1199 } 1200 1201 /* Need a dentry, since the xattr API requires one. 1202 Life would be simpler if we could just pass the inode. */ 1203 if (opt_dentry) { 1204 /* Called from d_instantiate or d_splice_alias. */ 1205 dentry = dget(opt_dentry); 1206 } else { 1207 /* Called from selinux_complete_init, try to find a dentry. */ 1208 dentry = d_find_alias(inode); 1209 } 1210 if (!dentry) { 1211 /* 1212 * this is can be hit on boot when a file is accessed 1213 * before the policy is loaded. When we load policy we 1214 * may find inodes that have no dentry on the 1215 * sbsec->isec_head list. No reason to complain as these 1216 * will get fixed up the next time we go through 1217 * inode_doinit with a dentry, before these inodes could 1218 * be used again by userspace. 1219 */ 1220 goto out_unlock; 1221 } 1222 1223 len = INITCONTEXTLEN; 1224 context = kmalloc(len+1, GFP_NOFS); 1225 if (!context) { 1226 rc = -ENOMEM; 1227 dput(dentry); 1228 goto out_unlock; 1229 } 1230 context[len] = '\0'; 1231 rc = inode->i_op->getxattr(dentry, XATTR_NAME_SELINUX, 1232 context, len); 1233 if (rc == -ERANGE) { 1234 kfree(context); 1235 1236 /* Need a larger buffer. Query for the right size. */ 1237 rc = inode->i_op->getxattr(dentry, XATTR_NAME_SELINUX, 1238 NULL, 0); 1239 if (rc < 0) { 1240 dput(dentry); 1241 goto out_unlock; 1242 } 1243 len = rc; 1244 context = kmalloc(len+1, GFP_NOFS); 1245 if (!context) { 1246 rc = -ENOMEM; 1247 dput(dentry); 1248 goto out_unlock; 1249 } 1250 context[len] = '\0'; 1251 rc = inode->i_op->getxattr(dentry, 1252 XATTR_NAME_SELINUX, 1253 context, len); 1254 } 1255 dput(dentry); 1256 if (rc < 0) { 1257 if (rc != -ENODATA) { 1258 printk(KERN_WARNING "SELinux: %s: getxattr returned " 1259 "%d for dev=%s ino=%ld\n", __func__, 1260 -rc, inode->i_sb->s_id, inode->i_ino); 1261 kfree(context); 1262 goto out_unlock; 1263 } 1264 /* Map ENODATA to the default file SID */ 1265 sid = sbsec->def_sid; 1266 rc = 0; 1267 } else { 1268 rc = security_context_to_sid_default(context, rc, &sid, 1269 sbsec->def_sid, 1270 GFP_NOFS); 1271 if (rc) { 1272 char *dev = inode->i_sb->s_id; 1273 unsigned long ino = inode->i_ino; 1274 1275 if (rc == -EINVAL) { 1276 if (printk_ratelimit()) 1277 printk(KERN_NOTICE "SELinux: inode=%lu on dev=%s was found to have an invalid " 1278 "context=%s. This indicates you may need to relabel the inode or the " 1279 "filesystem in question.\n", ino, dev, context); 1280 } else { 1281 printk(KERN_WARNING "SELinux: %s: context_to_sid(%s) " 1282 "returned %d for dev=%s ino=%ld\n", 1283 __func__, context, -rc, dev, ino); 1284 } 1285 kfree(context); 1286 /* Leave with the unlabeled SID */ 1287 rc = 0; 1288 break; 1289 } 1290 } 1291 kfree(context); 1292 isec->sid = sid; 1293 break; 1294 case SECURITY_FS_USE_TASK: 1295 isec->sid = isec->task_sid; 1296 break; 1297 case SECURITY_FS_USE_TRANS: 1298 /* Default to the fs SID. */ 1299 isec->sid = sbsec->sid; 1300 1301 /* Try to obtain a transition SID. */ 1302 isec->sclass = inode_mode_to_security_class(inode->i_mode); 1303 rc = security_transition_sid(isec->task_sid, sbsec->sid, 1304 isec->sclass, NULL, &sid); 1305 if (rc) 1306 goto out_unlock; 1307 isec->sid = sid; 1308 break; 1309 case SECURITY_FS_USE_MNTPOINT: 1310 isec->sid = sbsec->mntpoint_sid; 1311 break; 1312 default: 1313 /* Default to the fs superblock SID. */ 1314 isec->sid = sbsec->sid; 1315 1316 if ((sbsec->flags & SE_SBPROC) && !S_ISLNK(inode->i_mode)) { 1317 if (opt_dentry) { 1318 isec->sclass = inode_mode_to_security_class(inode->i_mode); 1319 rc = selinux_proc_get_sid(opt_dentry, 1320 isec->sclass, 1321 &sid); 1322 if (rc) 1323 goto out_unlock; 1324 isec->sid = sid; 1325 } 1326 } 1327 break; 1328 } 1329 1330 isec->initialized = 1; 1331 1332 out_unlock: 1333 mutex_unlock(&isec->lock); 1334 out: 1335 if (isec->sclass == SECCLASS_FILE) 1336 isec->sclass = inode_mode_to_security_class(inode->i_mode); 1337 return rc; 1338 } 1339 1340 /* Convert a Linux signal to an access vector. */ 1341 static inline u32 signal_to_av(int sig) 1342 { 1343 u32 perm = 0; 1344 1345 switch (sig) { 1346 case SIGCHLD: 1347 /* Commonly granted from child to parent. */ 1348 perm = PROCESS__SIGCHLD; 1349 break; 1350 case SIGKILL: 1351 /* Cannot be caught or ignored */ 1352 perm = PROCESS__SIGKILL; 1353 break; 1354 case SIGSTOP: 1355 /* Cannot be caught or ignored */ 1356 perm = PROCESS__SIGSTOP; 1357 break; 1358 default: 1359 /* All other signals. */ 1360 perm = PROCESS__SIGNAL; 1361 break; 1362 } 1363 1364 return perm; 1365 } 1366 1367 /* 1368 * Check permission between a pair of credentials 1369 * fork check, ptrace check, etc. 1370 */ 1371 static int cred_has_perm(const struct cred *actor, 1372 const struct cred *target, 1373 u32 perms) 1374 { 1375 u32 asid = cred_sid(actor), tsid = cred_sid(target); 1376 1377 return avc_has_perm(asid, tsid, SECCLASS_PROCESS, perms, NULL); 1378 } 1379 1380 /* 1381 * Check permission between a pair of tasks, e.g. signal checks, 1382 * fork check, ptrace check, etc. 1383 * tsk1 is the actor and tsk2 is the target 1384 * - this uses the default subjective creds of tsk1 1385 */ 1386 static int task_has_perm(const struct task_struct *tsk1, 1387 const struct task_struct *tsk2, 1388 u32 perms) 1389 { 1390 const struct task_security_struct *__tsec1, *__tsec2; 1391 u32 sid1, sid2; 1392 1393 rcu_read_lock(); 1394 __tsec1 = __task_cred(tsk1)->security; sid1 = __tsec1->sid; 1395 __tsec2 = __task_cred(tsk2)->security; sid2 = __tsec2->sid; 1396 rcu_read_unlock(); 1397 return avc_has_perm(sid1, sid2, SECCLASS_PROCESS, perms, NULL); 1398 } 1399 1400 /* 1401 * Check permission between current and another task, e.g. signal checks, 1402 * fork check, ptrace check, etc. 1403 * current is the actor and tsk2 is the target 1404 * - this uses current's subjective creds 1405 */ 1406 static int current_has_perm(const struct task_struct *tsk, 1407 u32 perms) 1408 { 1409 u32 sid, tsid; 1410 1411 sid = current_sid(); 1412 tsid = task_sid(tsk); 1413 return avc_has_perm(sid, tsid, SECCLASS_PROCESS, perms, NULL); 1414 } 1415 1416 #if CAP_LAST_CAP > 63 1417 #error Fix SELinux to handle capabilities > 63. 1418 #endif 1419 1420 /* Check whether a task is allowed to use a capability. */ 1421 static int task_has_capability(struct task_struct *tsk, 1422 const struct cred *cred, 1423 int cap, int audit) 1424 { 1425 struct common_audit_data ad; 1426 struct av_decision avd; 1427 u16 sclass; 1428 u32 sid = cred_sid(cred); 1429 u32 av = CAP_TO_MASK(cap); 1430 int rc; 1431 1432 COMMON_AUDIT_DATA_INIT(&ad, CAP); 1433 ad.tsk = tsk; 1434 ad.u.cap = cap; 1435 1436 switch (CAP_TO_INDEX(cap)) { 1437 case 0: 1438 sclass = SECCLASS_CAPABILITY; 1439 break; 1440 case 1: 1441 sclass = SECCLASS_CAPABILITY2; 1442 break; 1443 default: 1444 printk(KERN_ERR 1445 "SELinux: out of range capability %d\n", cap); 1446 BUG(); 1447 return -EINVAL; 1448 } 1449 1450 rc = avc_has_perm_noaudit(sid, sid, sclass, av, 0, &avd); 1451 if (audit == SECURITY_CAP_AUDIT) { 1452 int rc2 = avc_audit(sid, sid, sclass, av, &avd, rc, &ad, 0); 1453 if (rc2) 1454 return rc2; 1455 } 1456 return rc; 1457 } 1458 1459 /* Check whether a task is allowed to use a system operation. */ 1460 static int task_has_system(struct task_struct *tsk, 1461 u32 perms) 1462 { 1463 u32 sid = task_sid(tsk); 1464 1465 return avc_has_perm(sid, SECINITSID_KERNEL, 1466 SECCLASS_SYSTEM, perms, NULL); 1467 } 1468 1469 /* Check whether a task has a particular permission to an inode. 1470 The 'adp' parameter is optional and allows other audit 1471 data to be passed (e.g. the dentry). */ 1472 static int inode_has_perm(const struct cred *cred, 1473 struct inode *inode, 1474 u32 perms, 1475 struct common_audit_data *adp, 1476 unsigned flags) 1477 { 1478 struct inode_security_struct *isec; 1479 u32 sid; 1480 1481 validate_creds(cred); 1482 1483 if (unlikely(IS_PRIVATE(inode))) 1484 return 0; 1485 1486 sid = cred_sid(cred); 1487 isec = inode->i_security; 1488 1489 return avc_has_perm_flags(sid, isec->sid, isec->sclass, perms, adp, flags); 1490 } 1491 1492 static int inode_has_perm_noadp(const struct cred *cred, 1493 struct inode *inode, 1494 u32 perms, 1495 unsigned flags) 1496 { 1497 struct common_audit_data ad; 1498 1499 COMMON_AUDIT_DATA_INIT(&ad, INODE); 1500 ad.u.inode = inode; 1501 return inode_has_perm(cred, inode, perms, &ad, flags); 1502 } 1503 1504 /* Same as inode_has_perm, but pass explicit audit data containing 1505 the dentry to help the auditing code to more easily generate the 1506 pathname if needed. */ 1507 static inline int dentry_has_perm(const struct cred *cred, 1508 struct dentry *dentry, 1509 u32 av) 1510 { 1511 struct inode *inode = dentry->d_inode; 1512 struct common_audit_data ad; 1513 1514 COMMON_AUDIT_DATA_INIT(&ad, DENTRY); 1515 ad.u.dentry = dentry; 1516 return inode_has_perm(cred, inode, av, &ad, 0); 1517 } 1518 1519 /* Same as inode_has_perm, but pass explicit audit data containing 1520 the path to help the auditing code to more easily generate the 1521 pathname if needed. */ 1522 static inline int path_has_perm(const struct cred *cred, 1523 struct path *path, 1524 u32 av) 1525 { 1526 struct inode *inode = path->dentry->d_inode; 1527 struct common_audit_data ad; 1528 1529 COMMON_AUDIT_DATA_INIT(&ad, PATH); 1530 ad.u.path = *path; 1531 return inode_has_perm(cred, inode, av, &ad, 0); 1532 } 1533 1534 /* Check whether a task can use an open file descriptor to 1535 access an inode in a given way. Check access to the 1536 descriptor itself, and then use dentry_has_perm to 1537 check a particular permission to the file. 1538 Access to the descriptor is implicitly granted if it 1539 has the same SID as the process. If av is zero, then 1540 access to the file is not checked, e.g. for cases 1541 where only the descriptor is affected like seek. */ 1542 static int file_has_perm(const struct cred *cred, 1543 struct file *file, 1544 u32 av) 1545 { 1546 struct file_security_struct *fsec = file->f_security; 1547 struct inode *inode = file->f_path.dentry->d_inode; 1548 struct common_audit_data ad; 1549 u32 sid = cred_sid(cred); 1550 int rc; 1551 1552 COMMON_AUDIT_DATA_INIT(&ad, PATH); 1553 ad.u.path = file->f_path; 1554 1555 if (sid != fsec->sid) { 1556 rc = avc_has_perm(sid, fsec->sid, 1557 SECCLASS_FD, 1558 FD__USE, 1559 &ad); 1560 if (rc) 1561 goto out; 1562 } 1563 1564 /* av is zero if only checking access to the descriptor. */ 1565 rc = 0; 1566 if (av) 1567 rc = inode_has_perm(cred, inode, av, &ad, 0); 1568 1569 out: 1570 return rc; 1571 } 1572 1573 /* Check whether a task can create a file. */ 1574 static int may_create(struct inode *dir, 1575 struct dentry *dentry, 1576 u16 tclass) 1577 { 1578 const struct task_security_struct *tsec = current_security(); 1579 struct inode_security_struct *dsec; 1580 struct superblock_security_struct *sbsec; 1581 u32 sid, newsid; 1582 struct common_audit_data ad; 1583 int rc; 1584 1585 dsec = dir->i_security; 1586 sbsec = dir->i_sb->s_security; 1587 1588 sid = tsec->sid; 1589 newsid = tsec->create_sid; 1590 1591 COMMON_AUDIT_DATA_INIT(&ad, DENTRY); 1592 ad.u.dentry = dentry; 1593 1594 rc = avc_has_perm(sid, dsec->sid, SECCLASS_DIR, 1595 DIR__ADD_NAME | DIR__SEARCH, 1596 &ad); 1597 if (rc) 1598 return rc; 1599 1600 if (!newsid || !(sbsec->flags & SE_SBLABELSUPP)) { 1601 rc = security_transition_sid(sid, dsec->sid, tclass, 1602 &dentry->d_name, &newsid); 1603 if (rc) 1604 return rc; 1605 } 1606 1607 rc = avc_has_perm(sid, newsid, tclass, FILE__CREATE, &ad); 1608 if (rc) 1609 return rc; 1610 1611 return avc_has_perm(newsid, sbsec->sid, 1612 SECCLASS_FILESYSTEM, 1613 FILESYSTEM__ASSOCIATE, &ad); 1614 } 1615 1616 /* Check whether a task can create a key. */ 1617 static int may_create_key(u32 ksid, 1618 struct task_struct *ctx) 1619 { 1620 u32 sid = task_sid(ctx); 1621 1622 return avc_has_perm(sid, ksid, SECCLASS_KEY, KEY__CREATE, NULL); 1623 } 1624 1625 #define MAY_LINK 0 1626 #define MAY_UNLINK 1 1627 #define MAY_RMDIR 2 1628 1629 /* Check whether a task can link, unlink, or rmdir a file/directory. */ 1630 static int may_link(struct inode *dir, 1631 struct dentry *dentry, 1632 int kind) 1633 1634 { 1635 struct inode_security_struct *dsec, *isec; 1636 struct common_audit_data ad; 1637 u32 sid = current_sid(); 1638 u32 av; 1639 int rc; 1640 1641 dsec = dir->i_security; 1642 isec = dentry->d_inode->i_security; 1643 1644 COMMON_AUDIT_DATA_INIT(&ad, DENTRY); 1645 ad.u.dentry = dentry; 1646 1647 av = DIR__SEARCH; 1648 av |= (kind ? DIR__REMOVE_NAME : DIR__ADD_NAME); 1649 rc = avc_has_perm(sid, dsec->sid, SECCLASS_DIR, av, &ad); 1650 if (rc) 1651 return rc; 1652 1653 switch (kind) { 1654 case MAY_LINK: 1655 av = FILE__LINK; 1656 break; 1657 case MAY_UNLINK: 1658 av = FILE__UNLINK; 1659 break; 1660 case MAY_RMDIR: 1661 av = DIR__RMDIR; 1662 break; 1663 default: 1664 printk(KERN_WARNING "SELinux: %s: unrecognized kind %d\n", 1665 __func__, kind); 1666 return 0; 1667 } 1668 1669 rc = avc_has_perm(sid, isec->sid, isec->sclass, av, &ad); 1670 return rc; 1671 } 1672 1673 static inline int may_rename(struct inode *old_dir, 1674 struct dentry *old_dentry, 1675 struct inode *new_dir, 1676 struct dentry *new_dentry) 1677 { 1678 struct inode_security_struct *old_dsec, *new_dsec, *old_isec, *new_isec; 1679 struct common_audit_data ad; 1680 u32 sid = current_sid(); 1681 u32 av; 1682 int old_is_dir, new_is_dir; 1683 int rc; 1684 1685 old_dsec = old_dir->i_security; 1686 old_isec = old_dentry->d_inode->i_security; 1687 old_is_dir = S_ISDIR(old_dentry->d_inode->i_mode); 1688 new_dsec = new_dir->i_security; 1689 1690 COMMON_AUDIT_DATA_INIT(&ad, DENTRY); 1691 1692 ad.u.dentry = old_dentry; 1693 rc = avc_has_perm(sid, old_dsec->sid, SECCLASS_DIR, 1694 DIR__REMOVE_NAME | DIR__SEARCH, &ad); 1695 if (rc) 1696 return rc; 1697 rc = avc_has_perm(sid, old_isec->sid, 1698 old_isec->sclass, FILE__RENAME, &ad); 1699 if (rc) 1700 return rc; 1701 if (old_is_dir && new_dir != old_dir) { 1702 rc = avc_has_perm(sid, old_isec->sid, 1703 old_isec->sclass, DIR__REPARENT, &ad); 1704 if (rc) 1705 return rc; 1706 } 1707 1708 ad.u.dentry = new_dentry; 1709 av = DIR__ADD_NAME | DIR__SEARCH; 1710 if (new_dentry->d_inode) 1711 av |= DIR__REMOVE_NAME; 1712 rc = avc_has_perm(sid, new_dsec->sid, SECCLASS_DIR, av, &ad); 1713 if (rc) 1714 return rc; 1715 if (new_dentry->d_inode) { 1716 new_isec = new_dentry->d_inode->i_security; 1717 new_is_dir = S_ISDIR(new_dentry->d_inode->i_mode); 1718 rc = avc_has_perm(sid, new_isec->sid, 1719 new_isec->sclass, 1720 (new_is_dir ? DIR__RMDIR : FILE__UNLINK), &ad); 1721 if (rc) 1722 return rc; 1723 } 1724 1725 return 0; 1726 } 1727 1728 /* Check whether a task can perform a filesystem operation. */ 1729 static int superblock_has_perm(const struct cred *cred, 1730 struct super_block *sb, 1731 u32 perms, 1732 struct common_audit_data *ad) 1733 { 1734 struct superblock_security_struct *sbsec; 1735 u32 sid = cred_sid(cred); 1736 1737 sbsec = sb->s_security; 1738 return avc_has_perm(sid, sbsec->sid, SECCLASS_FILESYSTEM, perms, ad); 1739 } 1740 1741 /* Convert a Linux mode and permission mask to an access vector. */ 1742 static inline u32 file_mask_to_av(int mode, int mask) 1743 { 1744 u32 av = 0; 1745 1746 if ((mode & S_IFMT) != S_IFDIR) { 1747 if (mask & MAY_EXEC) 1748 av |= FILE__EXECUTE; 1749 if (mask & MAY_READ) 1750 av |= FILE__READ; 1751 1752 if (mask & MAY_APPEND) 1753 av |= FILE__APPEND; 1754 else if (mask & MAY_WRITE) 1755 av |= FILE__WRITE; 1756 1757 } else { 1758 if (mask & MAY_EXEC) 1759 av |= DIR__SEARCH; 1760 if (mask & MAY_WRITE) 1761 av |= DIR__WRITE; 1762 if (mask & MAY_READ) 1763 av |= DIR__READ; 1764 } 1765 1766 return av; 1767 } 1768 1769 /* Convert a Linux file to an access vector. */ 1770 static inline u32 file_to_av(struct file *file) 1771 { 1772 u32 av = 0; 1773 1774 if (file->f_mode & FMODE_READ) 1775 av |= FILE__READ; 1776 if (file->f_mode & FMODE_WRITE) { 1777 if (file->f_flags & O_APPEND) 1778 av |= FILE__APPEND; 1779 else 1780 av |= FILE__WRITE; 1781 } 1782 if (!av) { 1783 /* 1784 * Special file opened with flags 3 for ioctl-only use. 1785 */ 1786 av = FILE__IOCTL; 1787 } 1788 1789 return av; 1790 } 1791 1792 /* 1793 * Convert a file to an access vector and include the correct open 1794 * open permission. 1795 */ 1796 static inline u32 open_file_to_av(struct file *file) 1797 { 1798 u32 av = file_to_av(file); 1799 1800 if (selinux_policycap_openperm) 1801 av |= FILE__OPEN; 1802 1803 return av; 1804 } 1805 1806 /* Hook functions begin here. */ 1807 1808 static int selinux_ptrace_access_check(struct task_struct *child, 1809 unsigned int mode) 1810 { 1811 int rc; 1812 1813 rc = cap_ptrace_access_check(child, mode); 1814 if (rc) 1815 return rc; 1816 1817 if (mode == PTRACE_MODE_READ) { 1818 u32 sid = current_sid(); 1819 u32 csid = task_sid(child); 1820 return avc_has_perm(sid, csid, SECCLASS_FILE, FILE__READ, NULL); 1821 } 1822 1823 return current_has_perm(child, PROCESS__PTRACE); 1824 } 1825 1826 static int selinux_ptrace_traceme(struct task_struct *parent) 1827 { 1828 int rc; 1829 1830 rc = cap_ptrace_traceme(parent); 1831 if (rc) 1832 return rc; 1833 1834 return task_has_perm(parent, current, PROCESS__PTRACE); 1835 } 1836 1837 static int selinux_capget(struct task_struct *target, kernel_cap_t *effective, 1838 kernel_cap_t *inheritable, kernel_cap_t *permitted) 1839 { 1840 int error; 1841 1842 error = current_has_perm(target, PROCESS__GETCAP); 1843 if (error) 1844 return error; 1845 1846 return cap_capget(target, effective, inheritable, permitted); 1847 } 1848 1849 static int selinux_capset(struct cred *new, const struct cred *old, 1850 const kernel_cap_t *effective, 1851 const kernel_cap_t *inheritable, 1852 const kernel_cap_t *permitted) 1853 { 1854 int error; 1855 1856 error = cap_capset(new, old, 1857 effective, inheritable, permitted); 1858 if (error) 1859 return error; 1860 1861 return cred_has_perm(old, new, PROCESS__SETCAP); 1862 } 1863 1864 /* 1865 * (This comment used to live with the selinux_task_setuid hook, 1866 * which was removed). 1867 * 1868 * Since setuid only affects the current process, and since the SELinux 1869 * controls are not based on the Linux identity attributes, SELinux does not 1870 * need to control this operation. However, SELinux does control the use of 1871 * the CAP_SETUID and CAP_SETGID capabilities using the capable hook. 1872 */ 1873 1874 static int selinux_capable(struct task_struct *tsk, const struct cred *cred, 1875 struct user_namespace *ns, int cap, int audit) 1876 { 1877 int rc; 1878 1879 rc = cap_capable(tsk, cred, ns, cap, audit); 1880 if (rc) 1881 return rc; 1882 1883 return task_has_capability(tsk, cred, cap, audit); 1884 } 1885 1886 static int selinux_quotactl(int cmds, int type, int id, struct super_block *sb) 1887 { 1888 const struct cred *cred = current_cred(); 1889 int rc = 0; 1890 1891 if (!sb) 1892 return 0; 1893 1894 switch (cmds) { 1895 case Q_SYNC: 1896 case Q_QUOTAON: 1897 case Q_QUOTAOFF: 1898 case Q_SETINFO: 1899 case Q_SETQUOTA: 1900 rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAMOD, NULL); 1901 break; 1902 case Q_GETFMT: 1903 case Q_GETINFO: 1904 case Q_GETQUOTA: 1905 rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAGET, NULL); 1906 break; 1907 default: 1908 rc = 0; /* let the kernel handle invalid cmds */ 1909 break; 1910 } 1911 return rc; 1912 } 1913 1914 static int selinux_quota_on(struct dentry *dentry) 1915 { 1916 const struct cred *cred = current_cred(); 1917 1918 return dentry_has_perm(cred, dentry, FILE__QUOTAON); 1919 } 1920 1921 static int selinux_syslog(int type) 1922 { 1923 int rc; 1924 1925 switch (type) { 1926 case SYSLOG_ACTION_READ_ALL: /* Read last kernel messages */ 1927 case SYSLOG_ACTION_SIZE_BUFFER: /* Return size of the log buffer */ 1928 rc = task_has_system(current, SYSTEM__SYSLOG_READ); 1929 break; 1930 case SYSLOG_ACTION_CONSOLE_OFF: /* Disable logging to console */ 1931 case SYSLOG_ACTION_CONSOLE_ON: /* Enable logging to console */ 1932 /* Set level of messages printed to console */ 1933 case SYSLOG_ACTION_CONSOLE_LEVEL: 1934 rc = task_has_system(current, SYSTEM__SYSLOG_CONSOLE); 1935 break; 1936 case SYSLOG_ACTION_CLOSE: /* Close log */ 1937 case SYSLOG_ACTION_OPEN: /* Open log */ 1938 case SYSLOG_ACTION_READ: /* Read from log */ 1939 case SYSLOG_ACTION_READ_CLEAR: /* Read/clear last kernel messages */ 1940 case SYSLOG_ACTION_CLEAR: /* Clear ring buffer */ 1941 default: 1942 rc = task_has_system(current, SYSTEM__SYSLOG_MOD); 1943 break; 1944 } 1945 return rc; 1946 } 1947 1948 /* 1949 * Check that a process has enough memory to allocate a new virtual 1950 * mapping. 0 means there is enough memory for the allocation to 1951 * succeed and -ENOMEM implies there is not. 1952 * 1953 * Do not audit the selinux permission check, as this is applied to all 1954 * processes that allocate mappings. 1955 */ 1956 static int selinux_vm_enough_memory(struct mm_struct *mm, long pages) 1957 { 1958 int rc, cap_sys_admin = 0; 1959 1960 rc = selinux_capable(current, current_cred(), 1961 &init_user_ns, CAP_SYS_ADMIN, 1962 SECURITY_CAP_NOAUDIT); 1963 if (rc == 0) 1964 cap_sys_admin = 1; 1965 1966 return __vm_enough_memory(mm, pages, cap_sys_admin); 1967 } 1968 1969 /* binprm security operations */ 1970 1971 static int selinux_bprm_set_creds(struct linux_binprm *bprm) 1972 { 1973 const struct task_security_struct *old_tsec; 1974 struct task_security_struct *new_tsec; 1975 struct inode_security_struct *isec; 1976 struct common_audit_data ad; 1977 struct inode *inode = bprm->file->f_path.dentry->d_inode; 1978 int rc; 1979 1980 rc = cap_bprm_set_creds(bprm); 1981 if (rc) 1982 return rc; 1983 1984 /* SELinux context only depends on initial program or script and not 1985 * the script interpreter */ 1986 if (bprm->cred_prepared) 1987 return 0; 1988 1989 old_tsec = current_security(); 1990 new_tsec = bprm->cred->security; 1991 isec = inode->i_security; 1992 1993 /* Default to the current task SID. */ 1994 new_tsec->sid = old_tsec->sid; 1995 new_tsec->osid = old_tsec->sid; 1996 1997 /* Reset fs, key, and sock SIDs on execve. */ 1998 new_tsec->create_sid = 0; 1999 new_tsec->keycreate_sid = 0; 2000 new_tsec->sockcreate_sid = 0; 2001 2002 if (old_tsec->exec_sid) { 2003 new_tsec->sid = old_tsec->exec_sid; 2004 /* Reset exec SID on execve. */ 2005 new_tsec->exec_sid = 0; 2006 } else { 2007 /* Check for a default transition on this program. */ 2008 rc = security_transition_sid(old_tsec->sid, isec->sid, 2009 SECCLASS_PROCESS, NULL, 2010 &new_tsec->sid); 2011 if (rc) 2012 return rc; 2013 } 2014 2015 COMMON_AUDIT_DATA_INIT(&ad, PATH); 2016 ad.u.path = bprm->file->f_path; 2017 2018 if (bprm->file->f_path.mnt->mnt_flags & MNT_NOSUID) 2019 new_tsec->sid = old_tsec->sid; 2020 2021 if (new_tsec->sid == old_tsec->sid) { 2022 rc = avc_has_perm(old_tsec->sid, isec->sid, 2023 SECCLASS_FILE, FILE__EXECUTE_NO_TRANS, &ad); 2024 if (rc) 2025 return rc; 2026 } else { 2027 /* Check permissions for the transition. */ 2028 rc = avc_has_perm(old_tsec->sid, new_tsec->sid, 2029 SECCLASS_PROCESS, PROCESS__TRANSITION, &ad); 2030 if (rc) 2031 return rc; 2032 2033 rc = avc_has_perm(new_tsec->sid, isec->sid, 2034 SECCLASS_FILE, FILE__ENTRYPOINT, &ad); 2035 if (rc) 2036 return rc; 2037 2038 /* Check for shared state */ 2039 if (bprm->unsafe & LSM_UNSAFE_SHARE) { 2040 rc = avc_has_perm(old_tsec->sid, new_tsec->sid, 2041 SECCLASS_PROCESS, PROCESS__SHARE, 2042 NULL); 2043 if (rc) 2044 return -EPERM; 2045 } 2046 2047 /* Make sure that anyone attempting to ptrace over a task that 2048 * changes its SID has the appropriate permit */ 2049 if (bprm->unsafe & 2050 (LSM_UNSAFE_PTRACE | LSM_UNSAFE_PTRACE_CAP)) { 2051 struct task_struct *tracer; 2052 struct task_security_struct *sec; 2053 u32 ptsid = 0; 2054 2055 rcu_read_lock(); 2056 tracer = tracehook_tracer_task(current); 2057 if (likely(tracer != NULL)) { 2058 sec = __task_cred(tracer)->security; 2059 ptsid = sec->sid; 2060 } 2061 rcu_read_unlock(); 2062 2063 if (ptsid != 0) { 2064 rc = avc_has_perm(ptsid, new_tsec->sid, 2065 SECCLASS_PROCESS, 2066 PROCESS__PTRACE, NULL); 2067 if (rc) 2068 return -EPERM; 2069 } 2070 } 2071 2072 /* Clear any possibly unsafe personality bits on exec: */ 2073 bprm->per_clear |= PER_CLEAR_ON_SETID; 2074 } 2075 2076 return 0; 2077 } 2078 2079 static int selinux_bprm_secureexec(struct linux_binprm *bprm) 2080 { 2081 const struct task_security_struct *tsec = current_security(); 2082 u32 sid, osid; 2083 int atsecure = 0; 2084 2085 sid = tsec->sid; 2086 osid = tsec->osid; 2087 2088 if (osid != sid) { 2089 /* Enable secure mode for SIDs transitions unless 2090 the noatsecure permission is granted between 2091 the two SIDs, i.e. ahp returns 0. */ 2092 atsecure = avc_has_perm(osid, sid, 2093 SECCLASS_PROCESS, 2094 PROCESS__NOATSECURE, NULL); 2095 } 2096 2097 return (atsecure || cap_bprm_secureexec(bprm)); 2098 } 2099 2100 extern struct vfsmount *selinuxfs_mount; 2101 extern struct dentry *selinux_null; 2102 2103 /* Derived from fs/exec.c:flush_old_files. */ 2104 static inline void flush_unauthorized_files(const struct cred *cred, 2105 struct files_struct *files) 2106 { 2107 struct common_audit_data ad; 2108 struct file *file, *devnull = NULL; 2109 struct tty_struct *tty; 2110 struct fdtable *fdt; 2111 long j = -1; 2112 int drop_tty = 0; 2113 2114 tty = get_current_tty(); 2115 if (tty) { 2116 spin_lock(&tty_files_lock); 2117 if (!list_empty(&tty->tty_files)) { 2118 struct tty_file_private *file_priv; 2119 struct inode *inode; 2120 2121 /* Revalidate access to controlling tty. 2122 Use inode_has_perm on the tty inode directly rather 2123 than using file_has_perm, as this particular open 2124 file may belong to another process and we are only 2125 interested in the inode-based check here. */ 2126 file_priv = list_first_entry(&tty->tty_files, 2127 struct tty_file_private, list); 2128 file = file_priv->file; 2129 inode = file->f_path.dentry->d_inode; 2130 if (inode_has_perm_noadp(cred, inode, 2131 FILE__READ | FILE__WRITE, 0)) { 2132 drop_tty = 1; 2133 } 2134 } 2135 spin_unlock(&tty_files_lock); 2136 tty_kref_put(tty); 2137 } 2138 /* Reset controlling tty. */ 2139 if (drop_tty) 2140 no_tty(); 2141 2142 /* Revalidate access to inherited open files. */ 2143 2144 COMMON_AUDIT_DATA_INIT(&ad, INODE); 2145 2146 spin_lock(&files->file_lock); 2147 for (;;) { 2148 unsigned long set, i; 2149 int fd; 2150 2151 j++; 2152 i = j * __NFDBITS; 2153 fdt = files_fdtable(files); 2154 if (i >= fdt->max_fds) 2155 break; 2156 set = fdt->open_fds->fds_bits[j]; 2157 if (!set) 2158 continue; 2159 spin_unlock(&files->file_lock); 2160 for ( ; set ; i++, set >>= 1) { 2161 if (set & 1) { 2162 file = fget(i); 2163 if (!file) 2164 continue; 2165 if (file_has_perm(cred, 2166 file, 2167 file_to_av(file))) { 2168 sys_close(i); 2169 fd = get_unused_fd(); 2170 if (fd != i) { 2171 if (fd >= 0) 2172 put_unused_fd(fd); 2173 fput(file); 2174 continue; 2175 } 2176 if (devnull) { 2177 get_file(devnull); 2178 } else { 2179 devnull = dentry_open( 2180 dget(selinux_null), 2181 mntget(selinuxfs_mount), 2182 O_RDWR, cred); 2183 if (IS_ERR(devnull)) { 2184 devnull = NULL; 2185 put_unused_fd(fd); 2186 fput(file); 2187 continue; 2188 } 2189 } 2190 fd_install(fd, devnull); 2191 } 2192 fput(file); 2193 } 2194 } 2195 spin_lock(&files->file_lock); 2196 2197 } 2198 spin_unlock(&files->file_lock); 2199 } 2200 2201 /* 2202 * Prepare a process for imminent new credential changes due to exec 2203 */ 2204 static void selinux_bprm_committing_creds(struct linux_binprm *bprm) 2205 { 2206 struct task_security_struct *new_tsec; 2207 struct rlimit *rlim, *initrlim; 2208 int rc, i; 2209 2210 new_tsec = bprm->cred->security; 2211 if (new_tsec->sid == new_tsec->osid) 2212 return; 2213 2214 /* Close files for which the new task SID is not authorized. */ 2215 flush_unauthorized_files(bprm->cred, current->files); 2216 2217 /* Always clear parent death signal on SID transitions. */ 2218 current->pdeath_signal = 0; 2219 2220 /* Check whether the new SID can inherit resource limits from the old 2221 * SID. If not, reset all soft limits to the lower of the current 2222 * task's hard limit and the init task's soft limit. 2223 * 2224 * Note that the setting of hard limits (even to lower them) can be 2225 * controlled by the setrlimit check. The inclusion of the init task's 2226 * soft limit into the computation is to avoid resetting soft limits 2227 * higher than the default soft limit for cases where the default is 2228 * lower than the hard limit, e.g. RLIMIT_CORE or RLIMIT_STACK. 2229 */ 2230 rc = avc_has_perm(new_tsec->osid, new_tsec->sid, SECCLASS_PROCESS, 2231 PROCESS__RLIMITINH, NULL); 2232 if (rc) { 2233 /* protect against do_prlimit() */ 2234 task_lock(current); 2235 for (i = 0; i < RLIM_NLIMITS; i++) { 2236 rlim = current->signal->rlim + i; 2237 initrlim = init_task.signal->rlim + i; 2238 rlim->rlim_cur = min(rlim->rlim_max, initrlim->rlim_cur); 2239 } 2240 task_unlock(current); 2241 update_rlimit_cpu(current, rlimit(RLIMIT_CPU)); 2242 } 2243 } 2244 2245 /* 2246 * Clean up the process immediately after the installation of new credentials 2247 * due to exec 2248 */ 2249 static void selinux_bprm_committed_creds(struct linux_binprm *bprm) 2250 { 2251 const struct task_security_struct *tsec = current_security(); 2252 struct itimerval itimer; 2253 u32 osid, sid; 2254 int rc, i; 2255 2256 osid = tsec->osid; 2257 sid = tsec->sid; 2258 2259 if (sid == osid) 2260 return; 2261 2262 /* Check whether the new SID can inherit signal state from the old SID. 2263 * If not, clear itimers to avoid subsequent signal generation and 2264 * flush and unblock signals. 2265 * 2266 * This must occur _after_ the task SID has been updated so that any 2267 * kill done after the flush will be checked against the new SID. 2268 */ 2269 rc = avc_has_perm(osid, sid, SECCLASS_PROCESS, PROCESS__SIGINH, NULL); 2270 if (rc) { 2271 memset(&itimer, 0, sizeof itimer); 2272 for (i = 0; i < 3; i++) 2273 do_setitimer(i, &itimer, NULL); 2274 spin_lock_irq(¤t->sighand->siglock); 2275 if (!(current->signal->flags & SIGNAL_GROUP_EXIT)) { 2276 __flush_signals(current); 2277 flush_signal_handlers(current, 1); 2278 sigemptyset(¤t->blocked); 2279 } 2280 spin_unlock_irq(¤t->sighand->siglock); 2281 } 2282 2283 /* Wake up the parent if it is waiting so that it can recheck 2284 * wait permission to the new task SID. */ 2285 read_lock(&tasklist_lock); 2286 __wake_up_parent(current, current->real_parent); 2287 read_unlock(&tasklist_lock); 2288 } 2289 2290 /* superblock security operations */ 2291 2292 static int selinux_sb_alloc_security(struct super_block *sb) 2293 { 2294 return superblock_alloc_security(sb); 2295 } 2296 2297 static void selinux_sb_free_security(struct super_block *sb) 2298 { 2299 superblock_free_security(sb); 2300 } 2301 2302 static inline int match_prefix(char *prefix, int plen, char *option, int olen) 2303 { 2304 if (plen > olen) 2305 return 0; 2306 2307 return !memcmp(prefix, option, plen); 2308 } 2309 2310 static inline int selinux_option(char *option, int len) 2311 { 2312 return (match_prefix(CONTEXT_STR, sizeof(CONTEXT_STR)-1, option, len) || 2313 match_prefix(FSCONTEXT_STR, sizeof(FSCONTEXT_STR)-1, option, len) || 2314 match_prefix(DEFCONTEXT_STR, sizeof(DEFCONTEXT_STR)-1, option, len) || 2315 match_prefix(ROOTCONTEXT_STR, sizeof(ROOTCONTEXT_STR)-1, option, len) || 2316 match_prefix(LABELSUPP_STR, sizeof(LABELSUPP_STR)-1, option, len)); 2317 } 2318 2319 static inline void take_option(char **to, char *from, int *first, int len) 2320 { 2321 if (!*first) { 2322 **to = ','; 2323 *to += 1; 2324 } else 2325 *first = 0; 2326 memcpy(*to, from, len); 2327 *to += len; 2328 } 2329 2330 static inline void take_selinux_option(char **to, char *from, int *first, 2331 int len) 2332 { 2333 int current_size = 0; 2334 2335 if (!*first) { 2336 **to = '|'; 2337 *to += 1; 2338 } else 2339 *first = 0; 2340 2341 while (current_size < len) { 2342 if (*from != '"') { 2343 **to = *from; 2344 *to += 1; 2345 } 2346 from += 1; 2347 current_size += 1; 2348 } 2349 } 2350 2351 static int selinux_sb_copy_data(char *orig, char *copy) 2352 { 2353 int fnosec, fsec, rc = 0; 2354 char *in_save, *in_curr, *in_end; 2355 char *sec_curr, *nosec_save, *nosec; 2356 int open_quote = 0; 2357 2358 in_curr = orig; 2359 sec_curr = copy; 2360 2361 nosec = (char *)get_zeroed_page(GFP_KERNEL); 2362 if (!nosec) { 2363 rc = -ENOMEM; 2364 goto out; 2365 } 2366 2367 nosec_save = nosec; 2368 fnosec = fsec = 1; 2369 in_save = in_end = orig; 2370 2371 do { 2372 if (*in_end == '"') 2373 open_quote = !open_quote; 2374 if ((*in_end == ',' && open_quote == 0) || 2375 *in_end == '\0') { 2376 int len = in_end - in_curr; 2377 2378 if (selinux_option(in_curr, len)) 2379 take_selinux_option(&sec_curr, in_curr, &fsec, len); 2380 else 2381 take_option(&nosec, in_curr, &fnosec, len); 2382 2383 in_curr = in_end + 1; 2384 } 2385 } while (*in_end++); 2386 2387 strcpy(in_save, nosec_save); 2388 free_page((unsigned long)nosec_save); 2389 out: 2390 return rc; 2391 } 2392 2393 static int selinux_sb_remount(struct super_block *sb, void *data) 2394 { 2395 int rc, i, *flags; 2396 struct security_mnt_opts opts; 2397 char *secdata, **mount_options; 2398 struct superblock_security_struct *sbsec = sb->s_security; 2399 2400 if (!(sbsec->flags & SE_SBINITIALIZED)) 2401 return 0; 2402 2403 if (!data) 2404 return 0; 2405 2406 if (sb->s_type->fs_flags & FS_BINARY_MOUNTDATA) 2407 return 0; 2408 2409 security_init_mnt_opts(&opts); 2410 secdata = alloc_secdata(); 2411 if (!secdata) 2412 return -ENOMEM; 2413 rc = selinux_sb_copy_data(data, secdata); 2414 if (rc) 2415 goto out_free_secdata; 2416 2417 rc = selinux_parse_opts_str(secdata, &opts); 2418 if (rc) 2419 goto out_free_secdata; 2420 2421 mount_options = opts.mnt_opts; 2422 flags = opts.mnt_opts_flags; 2423 2424 for (i = 0; i < opts.num_mnt_opts; i++) { 2425 u32 sid; 2426 size_t len; 2427 2428 if (flags[i] == SE_SBLABELSUPP) 2429 continue; 2430 len = strlen(mount_options[i]); 2431 rc = security_context_to_sid(mount_options[i], len, &sid); 2432 if (rc) { 2433 printk(KERN_WARNING "SELinux: security_context_to_sid" 2434 "(%s) failed for (dev %s, type %s) errno=%d\n", 2435 mount_options[i], sb->s_id, sb->s_type->name, rc); 2436 goto out_free_opts; 2437 } 2438 rc = -EINVAL; 2439 switch (flags[i]) { 2440 case FSCONTEXT_MNT: 2441 if (bad_option(sbsec, FSCONTEXT_MNT, sbsec->sid, sid)) 2442 goto out_bad_option; 2443 break; 2444 case CONTEXT_MNT: 2445 if (bad_option(sbsec, CONTEXT_MNT, sbsec->mntpoint_sid, sid)) 2446 goto out_bad_option; 2447 break; 2448 case ROOTCONTEXT_MNT: { 2449 struct inode_security_struct *root_isec; 2450 root_isec = sb->s_root->d_inode->i_security; 2451 2452 if (bad_option(sbsec, ROOTCONTEXT_MNT, root_isec->sid, sid)) 2453 goto out_bad_option; 2454 break; 2455 } 2456 case DEFCONTEXT_MNT: 2457 if (bad_option(sbsec, DEFCONTEXT_MNT, sbsec->def_sid, sid)) 2458 goto out_bad_option; 2459 break; 2460 default: 2461 goto out_free_opts; 2462 } 2463 } 2464 2465 rc = 0; 2466 out_free_opts: 2467 security_free_mnt_opts(&opts); 2468 out_free_secdata: 2469 free_secdata(secdata); 2470 return rc; 2471 out_bad_option: 2472 printk(KERN_WARNING "SELinux: unable to change security options " 2473 "during remount (dev %s, type=%s)\n", sb->s_id, 2474 sb->s_type->name); 2475 goto out_free_opts; 2476 } 2477 2478 static int selinux_sb_kern_mount(struct super_block *sb, int flags, void *data) 2479 { 2480 const struct cred *cred = current_cred(); 2481 struct common_audit_data ad; 2482 int rc; 2483 2484 rc = superblock_doinit(sb, data); 2485 if (rc) 2486 return rc; 2487 2488 /* Allow all mounts performed by the kernel */ 2489 if (flags & MS_KERNMOUNT) 2490 return 0; 2491 2492 COMMON_AUDIT_DATA_INIT(&ad, DENTRY); 2493 ad.u.dentry = sb->s_root; 2494 return superblock_has_perm(cred, sb, FILESYSTEM__MOUNT, &ad); 2495 } 2496 2497 static int selinux_sb_statfs(struct dentry *dentry) 2498 { 2499 const struct cred *cred = current_cred(); 2500 struct common_audit_data ad; 2501 2502 COMMON_AUDIT_DATA_INIT(&ad, DENTRY); 2503 ad.u.dentry = dentry->d_sb->s_root; 2504 return superblock_has_perm(cred, dentry->d_sb, FILESYSTEM__GETATTR, &ad); 2505 } 2506 2507 static int selinux_mount(char *dev_name, 2508 struct path *path, 2509 char *type, 2510 unsigned long flags, 2511 void *data) 2512 { 2513 const struct cred *cred = current_cred(); 2514 2515 if (flags & MS_REMOUNT) 2516 return superblock_has_perm(cred, path->mnt->mnt_sb, 2517 FILESYSTEM__REMOUNT, NULL); 2518 else 2519 return path_has_perm(cred, path, FILE__MOUNTON); 2520 } 2521 2522 static int selinux_umount(struct vfsmount *mnt, int flags) 2523 { 2524 const struct cred *cred = current_cred(); 2525 2526 return superblock_has_perm(cred, mnt->mnt_sb, 2527 FILESYSTEM__UNMOUNT, NULL); 2528 } 2529 2530 /* inode security operations */ 2531 2532 static int selinux_inode_alloc_security(struct inode *inode) 2533 { 2534 return inode_alloc_security(inode); 2535 } 2536 2537 static void selinux_inode_free_security(struct inode *inode) 2538 { 2539 inode_free_security(inode); 2540 } 2541 2542 static int selinux_inode_init_security(struct inode *inode, struct inode *dir, 2543 const struct qstr *qstr, char **name, 2544 void **value, size_t *len) 2545 { 2546 const struct task_security_struct *tsec = current_security(); 2547 struct inode_security_struct *dsec; 2548 struct superblock_security_struct *sbsec; 2549 u32 sid, newsid, clen; 2550 int rc; 2551 char *namep = NULL, *context; 2552 2553 dsec = dir->i_security; 2554 sbsec = dir->i_sb->s_security; 2555 2556 sid = tsec->sid; 2557 newsid = tsec->create_sid; 2558 2559 if ((sbsec->flags & SE_SBINITIALIZED) && 2560 (sbsec->behavior == SECURITY_FS_USE_MNTPOINT)) 2561 newsid = sbsec->mntpoint_sid; 2562 else if (!newsid || !(sbsec->flags & SE_SBLABELSUPP)) { 2563 rc = security_transition_sid(sid, dsec->sid, 2564 inode_mode_to_security_class(inode->i_mode), 2565 qstr, &newsid); 2566 if (rc) { 2567 printk(KERN_WARNING "%s: " 2568 "security_transition_sid failed, rc=%d (dev=%s " 2569 "ino=%ld)\n", 2570 __func__, 2571 -rc, inode->i_sb->s_id, inode->i_ino); 2572 return rc; 2573 } 2574 } 2575 2576 /* Possibly defer initialization to selinux_complete_init. */ 2577 if (sbsec->flags & SE_SBINITIALIZED) { 2578 struct inode_security_struct *isec = inode->i_security; 2579 isec->sclass = inode_mode_to_security_class(inode->i_mode); 2580 isec->sid = newsid; 2581 isec->initialized = 1; 2582 } 2583 2584 if (!ss_initialized || !(sbsec->flags & SE_SBLABELSUPP)) 2585 return -EOPNOTSUPP; 2586 2587 if (name) { 2588 namep = kstrdup(XATTR_SELINUX_SUFFIX, GFP_NOFS); 2589 if (!namep) 2590 return -ENOMEM; 2591 *name = namep; 2592 } 2593 2594 if (value && len) { 2595 rc = security_sid_to_context_force(newsid, &context, &clen); 2596 if (rc) { 2597 kfree(namep); 2598 return rc; 2599 } 2600 *value = context; 2601 *len = clen; 2602 } 2603 2604 return 0; 2605 } 2606 2607 static int selinux_inode_create(struct inode *dir, struct dentry *dentry, int mask) 2608 { 2609 return may_create(dir, dentry, SECCLASS_FILE); 2610 } 2611 2612 static int selinux_inode_link(struct dentry *old_dentry, struct inode *dir, struct dentry *new_dentry) 2613 { 2614 return may_link(dir, old_dentry, MAY_LINK); 2615 } 2616 2617 static int selinux_inode_unlink(struct inode *dir, struct dentry *dentry) 2618 { 2619 return may_link(dir, dentry, MAY_UNLINK); 2620 } 2621 2622 static int selinux_inode_symlink(struct inode *dir, struct dentry *dentry, const char *name) 2623 { 2624 return may_create(dir, dentry, SECCLASS_LNK_FILE); 2625 } 2626 2627 static int selinux_inode_mkdir(struct inode *dir, struct dentry *dentry, int mask) 2628 { 2629 return may_create(dir, dentry, SECCLASS_DIR); 2630 } 2631 2632 static int selinux_inode_rmdir(struct inode *dir, struct dentry *dentry) 2633 { 2634 return may_link(dir, dentry, MAY_RMDIR); 2635 } 2636 2637 static int selinux_inode_mknod(struct inode *dir, struct dentry *dentry, int mode, dev_t dev) 2638 { 2639 return may_create(dir, dentry, inode_mode_to_security_class(mode)); 2640 } 2641 2642 static int selinux_inode_rename(struct inode *old_inode, struct dentry *old_dentry, 2643 struct inode *new_inode, struct dentry *new_dentry) 2644 { 2645 return may_rename(old_inode, old_dentry, new_inode, new_dentry); 2646 } 2647 2648 static int selinux_inode_readlink(struct dentry *dentry) 2649 { 2650 const struct cred *cred = current_cred(); 2651 2652 return dentry_has_perm(cred, dentry, FILE__READ); 2653 } 2654 2655 static int selinux_inode_follow_link(struct dentry *dentry, struct nameidata *nameidata) 2656 { 2657 const struct cred *cred = current_cred(); 2658 2659 return dentry_has_perm(cred, dentry, FILE__READ); 2660 } 2661 2662 static int selinux_inode_permission(struct inode *inode, int mask, unsigned flags) 2663 { 2664 const struct cred *cred = current_cred(); 2665 struct common_audit_data ad; 2666 u32 perms; 2667 bool from_access; 2668 2669 from_access = mask & MAY_ACCESS; 2670 mask &= (MAY_READ|MAY_WRITE|MAY_EXEC|MAY_APPEND); 2671 2672 /* No permission to check. Existence test. */ 2673 if (!mask) 2674 return 0; 2675 2676 COMMON_AUDIT_DATA_INIT(&ad, INODE); 2677 ad.u.inode = inode; 2678 2679 if (from_access) 2680 ad.selinux_audit_data.auditdeny |= FILE__AUDIT_ACCESS; 2681 2682 perms = file_mask_to_av(inode->i_mode, mask); 2683 2684 return inode_has_perm(cred, inode, perms, &ad, flags); 2685 } 2686 2687 static int selinux_inode_setattr(struct dentry *dentry, struct iattr *iattr) 2688 { 2689 const struct cred *cred = current_cred(); 2690 unsigned int ia_valid = iattr->ia_valid; 2691 2692 /* ATTR_FORCE is just used for ATTR_KILL_S[UG]ID. */ 2693 if (ia_valid & ATTR_FORCE) { 2694 ia_valid &= ~(ATTR_KILL_SUID | ATTR_KILL_SGID | ATTR_MODE | 2695 ATTR_FORCE); 2696 if (!ia_valid) 2697 return 0; 2698 } 2699 2700 if (ia_valid & (ATTR_MODE | ATTR_UID | ATTR_GID | 2701 ATTR_ATIME_SET | ATTR_MTIME_SET | ATTR_TIMES_SET)) 2702 return dentry_has_perm(cred, dentry, FILE__SETATTR); 2703 2704 return dentry_has_perm(cred, dentry, FILE__WRITE); 2705 } 2706 2707 static int selinux_inode_getattr(struct vfsmount *mnt, struct dentry *dentry) 2708 { 2709 const struct cred *cred = current_cred(); 2710 struct path path; 2711 2712 path.dentry = dentry; 2713 path.mnt = mnt; 2714 2715 return path_has_perm(cred, &path, FILE__GETATTR); 2716 } 2717 2718 static int selinux_inode_setotherxattr(struct dentry *dentry, const char *name) 2719 { 2720 const struct cred *cred = current_cred(); 2721 2722 if (!strncmp(name, XATTR_SECURITY_PREFIX, 2723 sizeof XATTR_SECURITY_PREFIX - 1)) { 2724 if (!strcmp(name, XATTR_NAME_CAPS)) { 2725 if (!capable(CAP_SETFCAP)) 2726 return -EPERM; 2727 } else if (!capable(CAP_SYS_ADMIN)) { 2728 /* A different attribute in the security namespace. 2729 Restrict to administrator. */ 2730 return -EPERM; 2731 } 2732 } 2733 2734 /* Not an attribute we recognize, so just check the 2735 ordinary setattr permission. */ 2736 return dentry_has_perm(cred, dentry, FILE__SETATTR); 2737 } 2738 2739 static int selinux_inode_setxattr(struct dentry *dentry, const char *name, 2740 const void *value, size_t size, int flags) 2741 { 2742 struct inode *inode = dentry->d_inode; 2743 struct inode_security_struct *isec = inode->i_security; 2744 struct superblock_security_struct *sbsec; 2745 struct common_audit_data ad; 2746 u32 newsid, sid = current_sid(); 2747 int rc = 0; 2748 2749 if (strcmp(name, XATTR_NAME_SELINUX)) 2750 return selinux_inode_setotherxattr(dentry, name); 2751 2752 sbsec = inode->i_sb->s_security; 2753 if (!(sbsec->flags & SE_SBLABELSUPP)) 2754 return -EOPNOTSUPP; 2755 2756 if (!inode_owner_or_capable(inode)) 2757 return -EPERM; 2758 2759 COMMON_AUDIT_DATA_INIT(&ad, DENTRY); 2760 ad.u.dentry = dentry; 2761 2762 rc = avc_has_perm(sid, isec->sid, isec->sclass, 2763 FILE__RELABELFROM, &ad); 2764 if (rc) 2765 return rc; 2766 2767 rc = security_context_to_sid(value, size, &newsid); 2768 if (rc == -EINVAL) { 2769 if (!capable(CAP_MAC_ADMIN)) 2770 return rc; 2771 rc = security_context_to_sid_force(value, size, &newsid); 2772 } 2773 if (rc) 2774 return rc; 2775 2776 rc = avc_has_perm(sid, newsid, isec->sclass, 2777 FILE__RELABELTO, &ad); 2778 if (rc) 2779 return rc; 2780 2781 rc = security_validate_transition(isec->sid, newsid, sid, 2782 isec->sclass); 2783 if (rc) 2784 return rc; 2785 2786 return avc_has_perm(newsid, 2787 sbsec->sid, 2788 SECCLASS_FILESYSTEM, 2789 FILESYSTEM__ASSOCIATE, 2790 &ad); 2791 } 2792 2793 static void selinux_inode_post_setxattr(struct dentry *dentry, const char *name, 2794 const void *value, size_t size, 2795 int flags) 2796 { 2797 struct inode *inode = dentry->d_inode; 2798 struct inode_security_struct *isec = inode->i_security; 2799 u32 newsid; 2800 int rc; 2801 2802 if (strcmp(name, XATTR_NAME_SELINUX)) { 2803 /* Not an attribute we recognize, so nothing to do. */ 2804 return; 2805 } 2806 2807 rc = security_context_to_sid_force(value, size, &newsid); 2808 if (rc) { 2809 printk(KERN_ERR "SELinux: unable to map context to SID" 2810 "for (%s, %lu), rc=%d\n", 2811 inode->i_sb->s_id, inode->i_ino, -rc); 2812 return; 2813 } 2814 2815 isec->sid = newsid; 2816 return; 2817 } 2818 2819 static int selinux_inode_getxattr(struct dentry *dentry, const char *name) 2820 { 2821 const struct cred *cred = current_cred(); 2822 2823 return dentry_has_perm(cred, dentry, FILE__GETATTR); 2824 } 2825 2826 static int selinux_inode_listxattr(struct dentry *dentry) 2827 { 2828 const struct cred *cred = current_cred(); 2829 2830 return dentry_has_perm(cred, dentry, FILE__GETATTR); 2831 } 2832 2833 static int selinux_inode_removexattr(struct dentry *dentry, const char *name) 2834 { 2835 if (strcmp(name, XATTR_NAME_SELINUX)) 2836 return selinux_inode_setotherxattr(dentry, name); 2837 2838 /* No one is allowed to remove a SELinux security label. 2839 You can change the label, but all data must be labeled. */ 2840 return -EACCES; 2841 } 2842 2843 /* 2844 * Copy the inode security context value to the user. 2845 * 2846 * Permission check is handled by selinux_inode_getxattr hook. 2847 */ 2848 static int selinux_inode_getsecurity(const struct inode *inode, const char *name, void **buffer, bool alloc) 2849 { 2850 u32 size; 2851 int error; 2852 char *context = NULL; 2853 struct inode_security_struct *isec = inode->i_security; 2854 2855 if (strcmp(name, XATTR_SELINUX_SUFFIX)) 2856 return -EOPNOTSUPP; 2857 2858 /* 2859 * If the caller has CAP_MAC_ADMIN, then get the raw context 2860 * value even if it is not defined by current policy; otherwise, 2861 * use the in-core value under current policy. 2862 * Use the non-auditing forms of the permission checks since 2863 * getxattr may be called by unprivileged processes commonly 2864 * and lack of permission just means that we fall back to the 2865 * in-core context value, not a denial. 2866 */ 2867 error = selinux_capable(current, current_cred(), 2868 &init_user_ns, CAP_MAC_ADMIN, 2869 SECURITY_CAP_NOAUDIT); 2870 if (!error) 2871 error = security_sid_to_context_force(isec->sid, &context, 2872 &size); 2873 else 2874 error = security_sid_to_context(isec->sid, &context, &size); 2875 if (error) 2876 return error; 2877 error = size; 2878 if (alloc) { 2879 *buffer = context; 2880 goto out_nofree; 2881 } 2882 kfree(context); 2883 out_nofree: 2884 return error; 2885 } 2886 2887 static int selinux_inode_setsecurity(struct inode *inode, const char *name, 2888 const void *value, size_t size, int flags) 2889 { 2890 struct inode_security_struct *isec = inode->i_security; 2891 u32 newsid; 2892 int rc; 2893 2894 if (strcmp(name, XATTR_SELINUX_SUFFIX)) 2895 return -EOPNOTSUPP; 2896 2897 if (!value || !size) 2898 return -EACCES; 2899 2900 rc = security_context_to_sid((void *)value, size, &newsid); 2901 if (rc) 2902 return rc; 2903 2904 isec->sid = newsid; 2905 isec->initialized = 1; 2906 return 0; 2907 } 2908 2909 static int selinux_inode_listsecurity(struct inode *inode, char *buffer, size_t buffer_size) 2910 { 2911 const int len = sizeof(XATTR_NAME_SELINUX); 2912 if (buffer && len <= buffer_size) 2913 memcpy(buffer, XATTR_NAME_SELINUX, len); 2914 return len; 2915 } 2916 2917 static void selinux_inode_getsecid(const struct inode *inode, u32 *secid) 2918 { 2919 struct inode_security_struct *isec = inode->i_security; 2920 *secid = isec->sid; 2921 } 2922 2923 /* file security operations */ 2924 2925 static int selinux_revalidate_file_permission(struct file *file, int mask) 2926 { 2927 const struct cred *cred = current_cred(); 2928 struct inode *inode = file->f_path.dentry->d_inode; 2929 2930 /* file_mask_to_av won't add FILE__WRITE if MAY_APPEND is set */ 2931 if ((file->f_flags & O_APPEND) && (mask & MAY_WRITE)) 2932 mask |= MAY_APPEND; 2933 2934 return file_has_perm(cred, file, 2935 file_mask_to_av(inode->i_mode, mask)); 2936 } 2937 2938 static int selinux_file_permission(struct file *file, int mask) 2939 { 2940 struct inode *inode = file->f_path.dentry->d_inode; 2941 struct file_security_struct *fsec = file->f_security; 2942 struct inode_security_struct *isec = inode->i_security; 2943 u32 sid = current_sid(); 2944 2945 if (!mask) 2946 /* No permission to check. Existence test. */ 2947 return 0; 2948 2949 if (sid == fsec->sid && fsec->isid == isec->sid && 2950 fsec->pseqno == avc_policy_seqno()) 2951 /* No change since dentry_open check. */ 2952 return 0; 2953 2954 return selinux_revalidate_file_permission(file, mask); 2955 } 2956 2957 static int selinux_file_alloc_security(struct file *file) 2958 { 2959 return file_alloc_security(file); 2960 } 2961 2962 static void selinux_file_free_security(struct file *file) 2963 { 2964 file_free_security(file); 2965 } 2966 2967 static int selinux_file_ioctl(struct file *file, unsigned int cmd, 2968 unsigned long arg) 2969 { 2970 const struct cred *cred = current_cred(); 2971 int error = 0; 2972 2973 switch (cmd) { 2974 case FIONREAD: 2975 /* fall through */ 2976 case FIBMAP: 2977 /* fall through */ 2978 case FIGETBSZ: 2979 /* fall through */ 2980 case EXT2_IOC_GETFLAGS: 2981 /* fall through */ 2982 case EXT2_IOC_GETVERSION: 2983 error = file_has_perm(cred, file, FILE__GETATTR); 2984 break; 2985 2986 case EXT2_IOC_SETFLAGS: 2987 /* fall through */ 2988 case EXT2_IOC_SETVERSION: 2989 error = file_has_perm(cred, file, FILE__SETATTR); 2990 break; 2991 2992 /* sys_ioctl() checks */ 2993 case FIONBIO: 2994 /* fall through */ 2995 case FIOASYNC: 2996 error = file_has_perm(cred, file, 0); 2997 break; 2998 2999 case KDSKBENT: 3000 case KDSKBSENT: 3001 error = task_has_capability(current, cred, CAP_SYS_TTY_CONFIG, 3002 SECURITY_CAP_AUDIT); 3003 break; 3004 3005 /* default case assumes that the command will go 3006 * to the file's ioctl() function. 3007 */ 3008 default: 3009 error = file_has_perm(cred, file, FILE__IOCTL); 3010 } 3011 return error; 3012 } 3013 3014 static int default_noexec; 3015 3016 static int file_map_prot_check(struct file *file, unsigned long prot, int shared) 3017 { 3018 const struct cred *cred = current_cred(); 3019 int rc = 0; 3020 3021 if (default_noexec && 3022 (prot & PROT_EXEC) && (!file || (!shared && (prot & PROT_WRITE)))) { 3023 /* 3024 * We are making executable an anonymous mapping or a 3025 * private file mapping that will also be writable. 3026 * This has an additional check. 3027 */ 3028 rc = cred_has_perm(cred, cred, PROCESS__EXECMEM); 3029 if (rc) 3030 goto error; 3031 } 3032 3033 if (file) { 3034 /* read access is always possible with a mapping */ 3035 u32 av = FILE__READ; 3036 3037 /* write access only matters if the mapping is shared */ 3038 if (shared && (prot & PROT_WRITE)) 3039 av |= FILE__WRITE; 3040 3041 if (prot & PROT_EXEC) 3042 av |= FILE__EXECUTE; 3043 3044 return file_has_perm(cred, file, av); 3045 } 3046 3047 error: 3048 return rc; 3049 } 3050 3051 static int selinux_file_mmap(struct file *file, unsigned long reqprot, 3052 unsigned long prot, unsigned long flags, 3053 unsigned long addr, unsigned long addr_only) 3054 { 3055 int rc = 0; 3056 u32 sid = current_sid(); 3057 3058 /* 3059 * notice that we are intentionally putting the SELinux check before 3060 * the secondary cap_file_mmap check. This is such a likely attempt 3061 * at bad behaviour/exploit that we always want to get the AVC, even 3062 * if DAC would have also denied the operation. 3063 */ 3064 if (addr < CONFIG_LSM_MMAP_MIN_ADDR) { 3065 rc = avc_has_perm(sid, sid, SECCLASS_MEMPROTECT, 3066 MEMPROTECT__MMAP_ZERO, NULL); 3067 if (rc) 3068 return rc; 3069 } 3070 3071 /* do DAC check on address space usage */ 3072 rc = cap_file_mmap(file, reqprot, prot, flags, addr, addr_only); 3073 if (rc || addr_only) 3074 return rc; 3075 3076 if (selinux_checkreqprot) 3077 prot = reqprot; 3078 3079 return file_map_prot_check(file, prot, 3080 (flags & MAP_TYPE) == MAP_SHARED); 3081 } 3082 3083 static int selinux_file_mprotect(struct vm_area_struct *vma, 3084 unsigned long reqprot, 3085 unsigned long prot) 3086 { 3087 const struct cred *cred = current_cred(); 3088 3089 if (selinux_checkreqprot) 3090 prot = reqprot; 3091 3092 if (default_noexec && 3093 (prot & PROT_EXEC) && !(vma->vm_flags & VM_EXEC)) { 3094 int rc = 0; 3095 if (vma->vm_start >= vma->vm_mm->start_brk && 3096 vma->vm_end <= vma->vm_mm->brk) { 3097 rc = cred_has_perm(cred, cred, PROCESS__EXECHEAP); 3098 } else if (!vma->vm_file && 3099 vma->vm_start <= vma->vm_mm->start_stack && 3100 vma->vm_end >= vma->vm_mm->start_stack) { 3101 rc = current_has_perm(current, PROCESS__EXECSTACK); 3102 } else if (vma->vm_file && vma->anon_vma) { 3103 /* 3104 * We are making executable a file mapping that has 3105 * had some COW done. Since pages might have been 3106 * written, check ability to execute the possibly 3107 * modified content. This typically should only 3108 * occur for text relocations. 3109 */ 3110 rc = file_has_perm(cred, vma->vm_file, FILE__EXECMOD); 3111 } 3112 if (rc) 3113 return rc; 3114 } 3115 3116 return file_map_prot_check(vma->vm_file, prot, vma->vm_flags&VM_SHARED); 3117 } 3118 3119 static int selinux_file_lock(struct file *file, unsigned int cmd) 3120 { 3121 const struct cred *cred = current_cred(); 3122 3123 return file_has_perm(cred, file, FILE__LOCK); 3124 } 3125 3126 static int selinux_file_fcntl(struct file *file, unsigned int cmd, 3127 unsigned long arg) 3128 { 3129 const struct cred *cred = current_cred(); 3130 int err = 0; 3131 3132 switch (cmd) { 3133 case F_SETFL: 3134 if (!file->f_path.dentry || !file->f_path.dentry->d_inode) { 3135 err = -EINVAL; 3136 break; 3137 } 3138 3139 if ((file->f_flags & O_APPEND) && !(arg & O_APPEND)) { 3140 err = file_has_perm(cred, file, FILE__WRITE); 3141 break; 3142 } 3143 /* fall through */ 3144 case F_SETOWN: 3145 case F_SETSIG: 3146 case F_GETFL: 3147 case F_GETOWN: 3148 case F_GETSIG: 3149 /* Just check FD__USE permission */ 3150 err = file_has_perm(cred, file, 0); 3151 break; 3152 case F_GETLK: 3153 case F_SETLK: 3154 case F_SETLKW: 3155 #if BITS_PER_LONG == 32 3156 case F_GETLK64: 3157 case F_SETLK64: 3158 case F_SETLKW64: 3159 #endif 3160 if (!file->f_path.dentry || !file->f_path.dentry->d_inode) { 3161 err = -EINVAL; 3162 break; 3163 } 3164 err = file_has_perm(cred, file, FILE__LOCK); 3165 break; 3166 } 3167 3168 return err; 3169 } 3170 3171 static int selinux_file_set_fowner(struct file *file) 3172 { 3173 struct file_security_struct *fsec; 3174 3175 fsec = file->f_security; 3176 fsec->fown_sid = current_sid(); 3177 3178 return 0; 3179 } 3180 3181 static int selinux_file_send_sigiotask(struct task_struct *tsk, 3182 struct fown_struct *fown, int signum) 3183 { 3184 struct file *file; 3185 u32 sid = task_sid(tsk); 3186 u32 perm; 3187 struct file_security_struct *fsec; 3188 3189 /* struct fown_struct is never outside the context of a struct file */ 3190 file = container_of(fown, struct file, f_owner); 3191 3192 fsec = file->f_security; 3193 3194 if (!signum) 3195 perm = signal_to_av(SIGIO); /* as per send_sigio_to_task */ 3196 else 3197 perm = signal_to_av(signum); 3198 3199 return avc_has_perm(fsec->fown_sid, sid, 3200 SECCLASS_PROCESS, perm, NULL); 3201 } 3202 3203 static int selinux_file_receive(struct file *file) 3204 { 3205 const struct cred *cred = current_cred(); 3206 3207 return file_has_perm(cred, file, file_to_av(file)); 3208 } 3209 3210 static int selinux_dentry_open(struct file *file, const struct cred *cred) 3211 { 3212 struct file_security_struct *fsec; 3213 struct inode *inode; 3214 struct inode_security_struct *isec; 3215 3216 inode = file->f_path.dentry->d_inode; 3217 fsec = file->f_security; 3218 isec = inode->i_security; 3219 /* 3220 * Save inode label and policy sequence number 3221 * at open-time so that selinux_file_permission 3222 * can determine whether revalidation is necessary. 3223 * Task label is already saved in the file security 3224 * struct as its SID. 3225 */ 3226 fsec->isid = isec->sid; 3227 fsec->pseqno = avc_policy_seqno(); 3228 /* 3229 * Since the inode label or policy seqno may have changed 3230 * between the selinux_inode_permission check and the saving 3231 * of state above, recheck that access is still permitted. 3232 * Otherwise, access might never be revalidated against the 3233 * new inode label or new policy. 3234 * This check is not redundant - do not remove. 3235 */ 3236 return inode_has_perm_noadp(cred, inode, open_file_to_av(file), 0); 3237 } 3238 3239 /* task security operations */ 3240 3241 static int selinux_task_create(unsigned long clone_flags) 3242 { 3243 return current_has_perm(current, PROCESS__FORK); 3244 } 3245 3246 /* 3247 * allocate the SELinux part of blank credentials 3248 */ 3249 static int selinux_cred_alloc_blank(struct cred *cred, gfp_t gfp) 3250 { 3251 struct task_security_struct *tsec; 3252 3253 tsec = kzalloc(sizeof(struct task_security_struct), gfp); 3254 if (!tsec) 3255 return -ENOMEM; 3256 3257 cred->security = tsec; 3258 return 0; 3259 } 3260 3261 /* 3262 * detach and free the LSM part of a set of credentials 3263 */ 3264 static void selinux_cred_free(struct cred *cred) 3265 { 3266 struct task_security_struct *tsec = cred->security; 3267 3268 /* 3269 * cred->security == NULL if security_cred_alloc_blank() or 3270 * security_prepare_creds() returned an error. 3271 */ 3272 BUG_ON(cred->security && (unsigned long) cred->security < PAGE_SIZE); 3273 cred->security = (void *) 0x7UL; 3274 kfree(tsec); 3275 } 3276 3277 /* 3278 * prepare a new set of credentials for modification 3279 */ 3280 static int selinux_cred_prepare(struct cred *new, const struct cred *old, 3281 gfp_t gfp) 3282 { 3283 const struct task_security_struct *old_tsec; 3284 struct task_security_struct *tsec; 3285 3286 old_tsec = old->security; 3287 3288 tsec = kmemdup(old_tsec, sizeof(struct task_security_struct), gfp); 3289 if (!tsec) 3290 return -ENOMEM; 3291 3292 new->security = tsec; 3293 return 0; 3294 } 3295 3296 /* 3297 * transfer the SELinux data to a blank set of creds 3298 */ 3299 static void selinux_cred_transfer(struct cred *new, const struct cred *old) 3300 { 3301 const struct task_security_struct *old_tsec = old->security; 3302 struct task_security_struct *tsec = new->security; 3303 3304 *tsec = *old_tsec; 3305 } 3306 3307 /* 3308 * set the security data for a kernel service 3309 * - all the creation contexts are set to unlabelled 3310 */ 3311 static int selinux_kernel_act_as(struct cred *new, u32 secid) 3312 { 3313 struct task_security_struct *tsec = new->security; 3314 u32 sid = current_sid(); 3315 int ret; 3316 3317 ret = avc_has_perm(sid, secid, 3318 SECCLASS_KERNEL_SERVICE, 3319 KERNEL_SERVICE__USE_AS_OVERRIDE, 3320 NULL); 3321 if (ret == 0) { 3322 tsec->sid = secid; 3323 tsec->create_sid = 0; 3324 tsec->keycreate_sid = 0; 3325 tsec->sockcreate_sid = 0; 3326 } 3327 return ret; 3328 } 3329 3330 /* 3331 * set the file creation context in a security record to the same as the 3332 * objective context of the specified inode 3333 */ 3334 static int selinux_kernel_create_files_as(struct cred *new, struct inode *inode) 3335 { 3336 struct inode_security_struct *isec = inode->i_security; 3337 struct task_security_struct *tsec = new->security; 3338 u32 sid = current_sid(); 3339 int ret; 3340 3341 ret = avc_has_perm(sid, isec->sid, 3342 SECCLASS_KERNEL_SERVICE, 3343 KERNEL_SERVICE__CREATE_FILES_AS, 3344 NULL); 3345 3346 if (ret == 0) 3347 tsec->create_sid = isec->sid; 3348 return ret; 3349 } 3350 3351 static int selinux_kernel_module_request(char *kmod_name) 3352 { 3353 u32 sid; 3354 struct common_audit_data ad; 3355 3356 sid = task_sid(current); 3357 3358 COMMON_AUDIT_DATA_INIT(&ad, KMOD); 3359 ad.u.kmod_name = kmod_name; 3360 3361 return avc_has_perm(sid, SECINITSID_KERNEL, SECCLASS_SYSTEM, 3362 SYSTEM__MODULE_REQUEST, &ad); 3363 } 3364 3365 static int selinux_task_setpgid(struct task_struct *p, pid_t pgid) 3366 { 3367 return current_has_perm(p, PROCESS__SETPGID); 3368 } 3369 3370 static int selinux_task_getpgid(struct task_struct *p) 3371 { 3372 return current_has_perm(p, PROCESS__GETPGID); 3373 } 3374 3375 static int selinux_task_getsid(struct task_struct *p) 3376 { 3377 return current_has_perm(p, PROCESS__GETSESSION); 3378 } 3379 3380 static void selinux_task_getsecid(struct task_struct *p, u32 *secid) 3381 { 3382 *secid = task_sid(p); 3383 } 3384 3385 static int selinux_task_setnice(struct task_struct *p, int nice) 3386 { 3387 int rc; 3388 3389 rc = cap_task_setnice(p, nice); 3390 if (rc) 3391 return rc; 3392 3393 return current_has_perm(p, PROCESS__SETSCHED); 3394 } 3395 3396 static int selinux_task_setioprio(struct task_struct *p, int ioprio) 3397 { 3398 int rc; 3399 3400 rc = cap_task_setioprio(p, ioprio); 3401 if (rc) 3402 return rc; 3403 3404 return current_has_perm(p, PROCESS__SETSCHED); 3405 } 3406 3407 static int selinux_task_getioprio(struct task_struct *p) 3408 { 3409 return current_has_perm(p, PROCESS__GETSCHED); 3410 } 3411 3412 static int selinux_task_setrlimit(struct task_struct *p, unsigned int resource, 3413 struct rlimit *new_rlim) 3414 { 3415 struct rlimit *old_rlim = p->signal->rlim + resource; 3416 3417 /* Control the ability to change the hard limit (whether 3418 lowering or raising it), so that the hard limit can 3419 later be used as a safe reset point for the soft limit 3420 upon context transitions. See selinux_bprm_committing_creds. */ 3421 if (old_rlim->rlim_max != new_rlim->rlim_max) 3422 return current_has_perm(p, PROCESS__SETRLIMIT); 3423 3424 return 0; 3425 } 3426 3427 static int selinux_task_setscheduler(struct task_struct *p) 3428 { 3429 int rc; 3430 3431 rc = cap_task_setscheduler(p); 3432 if (rc) 3433 return rc; 3434 3435 return current_has_perm(p, PROCESS__SETSCHED); 3436 } 3437 3438 static int selinux_task_getscheduler(struct task_struct *p) 3439 { 3440 return current_has_perm(p, PROCESS__GETSCHED); 3441 } 3442 3443 static int selinux_task_movememory(struct task_struct *p) 3444 { 3445 return current_has_perm(p, PROCESS__SETSCHED); 3446 } 3447 3448 static int selinux_task_kill(struct task_struct *p, struct siginfo *info, 3449 int sig, u32 secid) 3450 { 3451 u32 perm; 3452 int rc; 3453 3454 if (!sig) 3455 perm = PROCESS__SIGNULL; /* null signal; existence test */ 3456 else 3457 perm = signal_to_av(sig); 3458 if (secid) 3459 rc = avc_has_perm(secid, task_sid(p), 3460 SECCLASS_PROCESS, perm, NULL); 3461 else 3462 rc = current_has_perm(p, perm); 3463 return rc; 3464 } 3465 3466 static int selinux_task_wait(struct task_struct *p) 3467 { 3468 return task_has_perm(p, current, PROCESS__SIGCHLD); 3469 } 3470 3471 static void selinux_task_to_inode(struct task_struct *p, 3472 struct inode *inode) 3473 { 3474 struct inode_security_struct *isec = inode->i_security; 3475 u32 sid = task_sid(p); 3476 3477 isec->sid = sid; 3478 isec->initialized = 1; 3479 } 3480 3481 /* Returns error only if unable to parse addresses */ 3482 static int selinux_parse_skb_ipv4(struct sk_buff *skb, 3483 struct common_audit_data *ad, u8 *proto) 3484 { 3485 int offset, ihlen, ret = -EINVAL; 3486 struct iphdr _iph, *ih; 3487 3488 offset = skb_network_offset(skb); 3489 ih = skb_header_pointer(skb, offset, sizeof(_iph), &_iph); 3490 if (ih == NULL) 3491 goto out; 3492 3493 ihlen = ih->ihl * 4; 3494 if (ihlen < sizeof(_iph)) 3495 goto out; 3496 3497 ad->u.net.v4info.saddr = ih->saddr; 3498 ad->u.net.v4info.daddr = ih->daddr; 3499 ret = 0; 3500 3501 if (proto) 3502 *proto = ih->protocol; 3503 3504 switch (ih->protocol) { 3505 case IPPROTO_TCP: { 3506 struct tcphdr _tcph, *th; 3507 3508 if (ntohs(ih->frag_off) & IP_OFFSET) 3509 break; 3510 3511 offset += ihlen; 3512 th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph); 3513 if (th == NULL) 3514 break; 3515 3516 ad->u.net.sport = th->source; 3517 ad->u.net.dport = th->dest; 3518 break; 3519 } 3520 3521 case IPPROTO_UDP: { 3522 struct udphdr _udph, *uh; 3523 3524 if (ntohs(ih->frag_off) & IP_OFFSET) 3525 break; 3526 3527 offset += ihlen; 3528 uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph); 3529 if (uh == NULL) 3530 break; 3531 3532 ad->u.net.sport = uh->source; 3533 ad->u.net.dport = uh->dest; 3534 break; 3535 } 3536 3537 case IPPROTO_DCCP: { 3538 struct dccp_hdr _dccph, *dh; 3539 3540 if (ntohs(ih->frag_off) & IP_OFFSET) 3541 break; 3542 3543 offset += ihlen; 3544 dh = skb_header_pointer(skb, offset, sizeof(_dccph), &_dccph); 3545 if (dh == NULL) 3546 break; 3547 3548 ad->u.net.sport = dh->dccph_sport; 3549 ad->u.net.dport = dh->dccph_dport; 3550 break; 3551 } 3552 3553 default: 3554 break; 3555 } 3556 out: 3557 return ret; 3558 } 3559 3560 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE) 3561 3562 /* Returns error only if unable to parse addresses */ 3563 static int selinux_parse_skb_ipv6(struct sk_buff *skb, 3564 struct common_audit_data *ad, u8 *proto) 3565 { 3566 u8 nexthdr; 3567 int ret = -EINVAL, offset; 3568 struct ipv6hdr _ipv6h, *ip6; 3569 3570 offset = skb_network_offset(skb); 3571 ip6 = skb_header_pointer(skb, offset, sizeof(_ipv6h), &_ipv6h); 3572 if (ip6 == NULL) 3573 goto out; 3574 3575 ipv6_addr_copy(&ad->u.net.v6info.saddr, &ip6->saddr); 3576 ipv6_addr_copy(&ad->u.net.v6info.daddr, &ip6->daddr); 3577 ret = 0; 3578 3579 nexthdr = ip6->nexthdr; 3580 offset += sizeof(_ipv6h); 3581 offset = ipv6_skip_exthdr(skb, offset, &nexthdr); 3582 if (offset < 0) 3583 goto out; 3584 3585 if (proto) 3586 *proto = nexthdr; 3587 3588 switch (nexthdr) { 3589 case IPPROTO_TCP: { 3590 struct tcphdr _tcph, *th; 3591 3592 th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph); 3593 if (th == NULL) 3594 break; 3595 3596 ad->u.net.sport = th->source; 3597 ad->u.net.dport = th->dest; 3598 break; 3599 } 3600 3601 case IPPROTO_UDP: { 3602 struct udphdr _udph, *uh; 3603 3604 uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph); 3605 if (uh == NULL) 3606 break; 3607 3608 ad->u.net.sport = uh->source; 3609 ad->u.net.dport = uh->dest; 3610 break; 3611 } 3612 3613 case IPPROTO_DCCP: { 3614 struct dccp_hdr _dccph, *dh; 3615 3616 dh = skb_header_pointer(skb, offset, sizeof(_dccph), &_dccph); 3617 if (dh == NULL) 3618 break; 3619 3620 ad->u.net.sport = dh->dccph_sport; 3621 ad->u.net.dport = dh->dccph_dport; 3622 break; 3623 } 3624 3625 /* includes fragments */ 3626 default: 3627 break; 3628 } 3629 out: 3630 return ret; 3631 } 3632 3633 #endif /* IPV6 */ 3634 3635 static int selinux_parse_skb(struct sk_buff *skb, struct common_audit_data *ad, 3636 char **_addrp, int src, u8 *proto) 3637 { 3638 char *addrp; 3639 int ret; 3640 3641 switch (ad->u.net.family) { 3642 case PF_INET: 3643 ret = selinux_parse_skb_ipv4(skb, ad, proto); 3644 if (ret) 3645 goto parse_error; 3646 addrp = (char *)(src ? &ad->u.net.v4info.saddr : 3647 &ad->u.net.v4info.daddr); 3648 goto okay; 3649 3650 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE) 3651 case PF_INET6: 3652 ret = selinux_parse_skb_ipv6(skb, ad, proto); 3653 if (ret) 3654 goto parse_error; 3655 addrp = (char *)(src ? &ad->u.net.v6info.saddr : 3656 &ad->u.net.v6info.daddr); 3657 goto okay; 3658 #endif /* IPV6 */ 3659 default: 3660 addrp = NULL; 3661 goto okay; 3662 } 3663 3664 parse_error: 3665 printk(KERN_WARNING 3666 "SELinux: failure in selinux_parse_skb()," 3667 " unable to parse packet\n"); 3668 return ret; 3669 3670 okay: 3671 if (_addrp) 3672 *_addrp = addrp; 3673 return 0; 3674 } 3675 3676 /** 3677 * selinux_skb_peerlbl_sid - Determine the peer label of a packet 3678 * @skb: the packet 3679 * @family: protocol family 3680 * @sid: the packet's peer label SID 3681 * 3682 * Description: 3683 * Check the various different forms of network peer labeling and determine 3684 * the peer label/SID for the packet; most of the magic actually occurs in 3685 * the security server function security_net_peersid_cmp(). The function 3686 * returns zero if the value in @sid is valid (although it may be SECSID_NULL) 3687 * or -EACCES if @sid is invalid due to inconsistencies with the different 3688 * peer labels. 3689 * 3690 */ 3691 static int selinux_skb_peerlbl_sid(struct sk_buff *skb, u16 family, u32 *sid) 3692 { 3693 int err; 3694 u32 xfrm_sid; 3695 u32 nlbl_sid; 3696 u32 nlbl_type; 3697 3698 selinux_skb_xfrm_sid(skb, &xfrm_sid); 3699 selinux_netlbl_skbuff_getsid(skb, family, &nlbl_type, &nlbl_sid); 3700 3701 err = security_net_peersid_resolve(nlbl_sid, nlbl_type, xfrm_sid, sid); 3702 if (unlikely(err)) { 3703 printk(KERN_WARNING 3704 "SELinux: failure in selinux_skb_peerlbl_sid()," 3705 " unable to determine packet's peer label\n"); 3706 return -EACCES; 3707 } 3708 3709 return 0; 3710 } 3711 3712 /* socket security operations */ 3713 3714 static int socket_sockcreate_sid(const struct task_security_struct *tsec, 3715 u16 secclass, u32 *socksid) 3716 { 3717 if (tsec->sockcreate_sid > SECSID_NULL) { 3718 *socksid = tsec->sockcreate_sid; 3719 return 0; 3720 } 3721 3722 return security_transition_sid(tsec->sid, tsec->sid, secclass, NULL, 3723 socksid); 3724 } 3725 3726 static int sock_has_perm(struct task_struct *task, struct sock *sk, u32 perms) 3727 { 3728 struct sk_security_struct *sksec = sk->sk_security; 3729 struct common_audit_data ad; 3730 u32 tsid = task_sid(task); 3731 3732 if (sksec->sid == SECINITSID_KERNEL) 3733 return 0; 3734 3735 COMMON_AUDIT_DATA_INIT(&ad, NET); 3736 ad.u.net.sk = sk; 3737 3738 return avc_has_perm(tsid, sksec->sid, sksec->sclass, perms, &ad); 3739 } 3740 3741 static int selinux_socket_create(int family, int type, 3742 int protocol, int kern) 3743 { 3744 const struct task_security_struct *tsec = current_security(); 3745 u32 newsid; 3746 u16 secclass; 3747 int rc; 3748 3749 if (kern) 3750 return 0; 3751 3752 secclass = socket_type_to_security_class(family, type, protocol); 3753 rc = socket_sockcreate_sid(tsec, secclass, &newsid); 3754 if (rc) 3755 return rc; 3756 3757 return avc_has_perm(tsec->sid, newsid, secclass, SOCKET__CREATE, NULL); 3758 } 3759 3760 static int selinux_socket_post_create(struct socket *sock, int family, 3761 int type, int protocol, int kern) 3762 { 3763 const struct task_security_struct *tsec = current_security(); 3764 struct inode_security_struct *isec = SOCK_INODE(sock)->i_security; 3765 struct sk_security_struct *sksec; 3766 int err = 0; 3767 3768 isec->sclass = socket_type_to_security_class(family, type, protocol); 3769 3770 if (kern) 3771 isec->sid = SECINITSID_KERNEL; 3772 else { 3773 err = socket_sockcreate_sid(tsec, isec->sclass, &(isec->sid)); 3774 if (err) 3775 return err; 3776 } 3777 3778 isec->initialized = 1; 3779 3780 if (sock->sk) { 3781 sksec = sock->sk->sk_security; 3782 sksec->sid = isec->sid; 3783 sksec->sclass = isec->sclass; 3784 err = selinux_netlbl_socket_post_create(sock->sk, family); 3785 } 3786 3787 return err; 3788 } 3789 3790 /* Range of port numbers used to automatically bind. 3791 Need to determine whether we should perform a name_bind 3792 permission check between the socket and the port number. */ 3793 3794 static int selinux_socket_bind(struct socket *sock, struct sockaddr *address, int addrlen) 3795 { 3796 struct sock *sk = sock->sk; 3797 u16 family; 3798 int err; 3799 3800 err = sock_has_perm(current, sk, SOCKET__BIND); 3801 if (err) 3802 goto out; 3803 3804 /* 3805 * If PF_INET or PF_INET6, check name_bind permission for the port. 3806 * Multiple address binding for SCTP is not supported yet: we just 3807 * check the first address now. 3808 */ 3809 family = sk->sk_family; 3810 if (family == PF_INET || family == PF_INET6) { 3811 char *addrp; 3812 struct sk_security_struct *sksec = sk->sk_security; 3813 struct common_audit_data ad; 3814 struct sockaddr_in *addr4 = NULL; 3815 struct sockaddr_in6 *addr6 = NULL; 3816 unsigned short snum; 3817 u32 sid, node_perm; 3818 3819 if (family == PF_INET) { 3820 addr4 = (struct sockaddr_in *)address; 3821 snum = ntohs(addr4->sin_port); 3822 addrp = (char *)&addr4->sin_addr.s_addr; 3823 } else { 3824 addr6 = (struct sockaddr_in6 *)address; 3825 snum = ntohs(addr6->sin6_port); 3826 addrp = (char *)&addr6->sin6_addr.s6_addr; 3827 } 3828 3829 if (snum) { 3830 int low, high; 3831 3832 inet_get_local_port_range(&low, &high); 3833 3834 if (snum < max(PROT_SOCK, low) || snum > high) { 3835 err = sel_netport_sid(sk->sk_protocol, 3836 snum, &sid); 3837 if (err) 3838 goto out; 3839 COMMON_AUDIT_DATA_INIT(&ad, NET); 3840 ad.u.net.sport = htons(snum); 3841 ad.u.net.family = family; 3842 err = avc_has_perm(sksec->sid, sid, 3843 sksec->sclass, 3844 SOCKET__NAME_BIND, &ad); 3845 if (err) 3846 goto out; 3847 } 3848 } 3849 3850 switch (sksec->sclass) { 3851 case SECCLASS_TCP_SOCKET: 3852 node_perm = TCP_SOCKET__NODE_BIND; 3853 break; 3854 3855 case SECCLASS_UDP_SOCKET: 3856 node_perm = UDP_SOCKET__NODE_BIND; 3857 break; 3858 3859 case SECCLASS_DCCP_SOCKET: 3860 node_perm = DCCP_SOCKET__NODE_BIND; 3861 break; 3862 3863 default: 3864 node_perm = RAWIP_SOCKET__NODE_BIND; 3865 break; 3866 } 3867 3868 err = sel_netnode_sid(addrp, family, &sid); 3869 if (err) 3870 goto out; 3871 3872 COMMON_AUDIT_DATA_INIT(&ad, NET); 3873 ad.u.net.sport = htons(snum); 3874 ad.u.net.family = family; 3875 3876 if (family == PF_INET) 3877 ad.u.net.v4info.saddr = addr4->sin_addr.s_addr; 3878 else 3879 ipv6_addr_copy(&ad.u.net.v6info.saddr, &addr6->sin6_addr); 3880 3881 err = avc_has_perm(sksec->sid, sid, 3882 sksec->sclass, node_perm, &ad); 3883 if (err) 3884 goto out; 3885 } 3886 out: 3887 return err; 3888 } 3889 3890 static int selinux_socket_connect(struct socket *sock, struct sockaddr *address, int addrlen) 3891 { 3892 struct sock *sk = sock->sk; 3893 struct sk_security_struct *sksec = sk->sk_security; 3894 int err; 3895 3896 err = sock_has_perm(current, sk, SOCKET__CONNECT); 3897 if (err) 3898 return err; 3899 3900 /* 3901 * If a TCP or DCCP socket, check name_connect permission for the port. 3902 */ 3903 if (sksec->sclass == SECCLASS_TCP_SOCKET || 3904 sksec->sclass == SECCLASS_DCCP_SOCKET) { 3905 struct common_audit_data ad; 3906 struct sockaddr_in *addr4 = NULL; 3907 struct sockaddr_in6 *addr6 = NULL; 3908 unsigned short snum; 3909 u32 sid, perm; 3910 3911 if (sk->sk_family == PF_INET) { 3912 addr4 = (struct sockaddr_in *)address; 3913 if (addrlen < sizeof(struct sockaddr_in)) 3914 return -EINVAL; 3915 snum = ntohs(addr4->sin_port); 3916 } else { 3917 addr6 = (struct sockaddr_in6 *)address; 3918 if (addrlen < SIN6_LEN_RFC2133) 3919 return -EINVAL; 3920 snum = ntohs(addr6->sin6_port); 3921 } 3922 3923 err = sel_netport_sid(sk->sk_protocol, snum, &sid); 3924 if (err) 3925 goto out; 3926 3927 perm = (sksec->sclass == SECCLASS_TCP_SOCKET) ? 3928 TCP_SOCKET__NAME_CONNECT : DCCP_SOCKET__NAME_CONNECT; 3929 3930 COMMON_AUDIT_DATA_INIT(&ad, NET); 3931 ad.u.net.dport = htons(snum); 3932 ad.u.net.family = sk->sk_family; 3933 err = avc_has_perm(sksec->sid, sid, sksec->sclass, perm, &ad); 3934 if (err) 3935 goto out; 3936 } 3937 3938 err = selinux_netlbl_socket_connect(sk, address); 3939 3940 out: 3941 return err; 3942 } 3943 3944 static int selinux_socket_listen(struct socket *sock, int backlog) 3945 { 3946 return sock_has_perm(current, sock->sk, SOCKET__LISTEN); 3947 } 3948 3949 static int selinux_socket_accept(struct socket *sock, struct socket *newsock) 3950 { 3951 int err; 3952 struct inode_security_struct *isec; 3953 struct inode_security_struct *newisec; 3954 3955 err = sock_has_perm(current, sock->sk, SOCKET__ACCEPT); 3956 if (err) 3957 return err; 3958 3959 newisec = SOCK_INODE(newsock)->i_security; 3960 3961 isec = SOCK_INODE(sock)->i_security; 3962 newisec->sclass = isec->sclass; 3963 newisec->sid = isec->sid; 3964 newisec->initialized = 1; 3965 3966 return 0; 3967 } 3968 3969 static int selinux_socket_sendmsg(struct socket *sock, struct msghdr *msg, 3970 int size) 3971 { 3972 return sock_has_perm(current, sock->sk, SOCKET__WRITE); 3973 } 3974 3975 static int selinux_socket_recvmsg(struct socket *sock, struct msghdr *msg, 3976 int size, int flags) 3977 { 3978 return sock_has_perm(current, sock->sk, SOCKET__READ); 3979 } 3980 3981 static int selinux_socket_getsockname(struct socket *sock) 3982 { 3983 return sock_has_perm(current, sock->sk, SOCKET__GETATTR); 3984 } 3985 3986 static int selinux_socket_getpeername(struct socket *sock) 3987 { 3988 return sock_has_perm(current, sock->sk, SOCKET__GETATTR); 3989 } 3990 3991 static int selinux_socket_setsockopt(struct socket *sock, int level, int optname) 3992 { 3993 int err; 3994 3995 err = sock_has_perm(current, sock->sk, SOCKET__SETOPT); 3996 if (err) 3997 return err; 3998 3999 return selinux_netlbl_socket_setsockopt(sock, level, optname); 4000 } 4001 4002 static int selinux_socket_getsockopt(struct socket *sock, int level, 4003 int optname) 4004 { 4005 return sock_has_perm(current, sock->sk, SOCKET__GETOPT); 4006 } 4007 4008 static int selinux_socket_shutdown(struct socket *sock, int how) 4009 { 4010 return sock_has_perm(current, sock->sk, SOCKET__SHUTDOWN); 4011 } 4012 4013 static int selinux_socket_unix_stream_connect(struct sock *sock, 4014 struct sock *other, 4015 struct sock *newsk) 4016 { 4017 struct sk_security_struct *sksec_sock = sock->sk_security; 4018 struct sk_security_struct *sksec_other = other->sk_security; 4019 struct sk_security_struct *sksec_new = newsk->sk_security; 4020 struct common_audit_data ad; 4021 int err; 4022 4023 COMMON_AUDIT_DATA_INIT(&ad, NET); 4024 ad.u.net.sk = other; 4025 4026 err = avc_has_perm(sksec_sock->sid, sksec_other->sid, 4027 sksec_other->sclass, 4028 UNIX_STREAM_SOCKET__CONNECTTO, &ad); 4029 if (err) 4030 return err; 4031 4032 /* server child socket */ 4033 sksec_new->peer_sid = sksec_sock->sid; 4034 err = security_sid_mls_copy(sksec_other->sid, sksec_sock->sid, 4035 &sksec_new->sid); 4036 if (err) 4037 return err; 4038 4039 /* connecting socket */ 4040 sksec_sock->peer_sid = sksec_new->sid; 4041 4042 return 0; 4043 } 4044 4045 static int selinux_socket_unix_may_send(struct socket *sock, 4046 struct socket *other) 4047 { 4048 struct sk_security_struct *ssec = sock->sk->sk_security; 4049 struct sk_security_struct *osec = other->sk->sk_security; 4050 struct common_audit_data ad; 4051 4052 COMMON_AUDIT_DATA_INIT(&ad, NET); 4053 ad.u.net.sk = other->sk; 4054 4055 return avc_has_perm(ssec->sid, osec->sid, osec->sclass, SOCKET__SENDTO, 4056 &ad); 4057 } 4058 4059 static int selinux_inet_sys_rcv_skb(int ifindex, char *addrp, u16 family, 4060 u32 peer_sid, 4061 struct common_audit_data *ad) 4062 { 4063 int err; 4064 u32 if_sid; 4065 u32 node_sid; 4066 4067 err = sel_netif_sid(ifindex, &if_sid); 4068 if (err) 4069 return err; 4070 err = avc_has_perm(peer_sid, if_sid, 4071 SECCLASS_NETIF, NETIF__INGRESS, ad); 4072 if (err) 4073 return err; 4074 4075 err = sel_netnode_sid(addrp, family, &node_sid); 4076 if (err) 4077 return err; 4078 return avc_has_perm(peer_sid, node_sid, 4079 SECCLASS_NODE, NODE__RECVFROM, ad); 4080 } 4081 4082 static int selinux_sock_rcv_skb_compat(struct sock *sk, struct sk_buff *skb, 4083 u16 family) 4084 { 4085 int err = 0; 4086 struct sk_security_struct *sksec = sk->sk_security; 4087 u32 sk_sid = sksec->sid; 4088 struct common_audit_data ad; 4089 char *addrp; 4090 4091 COMMON_AUDIT_DATA_INIT(&ad, NET); 4092 ad.u.net.netif = skb->skb_iif; 4093 ad.u.net.family = family; 4094 err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL); 4095 if (err) 4096 return err; 4097 4098 if (selinux_secmark_enabled()) { 4099 err = avc_has_perm(sk_sid, skb->secmark, SECCLASS_PACKET, 4100 PACKET__RECV, &ad); 4101 if (err) 4102 return err; 4103 } 4104 4105 err = selinux_netlbl_sock_rcv_skb(sksec, skb, family, &ad); 4106 if (err) 4107 return err; 4108 err = selinux_xfrm_sock_rcv_skb(sksec->sid, skb, &ad); 4109 4110 return err; 4111 } 4112 4113 static int selinux_socket_sock_rcv_skb(struct sock *sk, struct sk_buff *skb) 4114 { 4115 int err; 4116 struct sk_security_struct *sksec = sk->sk_security; 4117 u16 family = sk->sk_family; 4118 u32 sk_sid = sksec->sid; 4119 struct common_audit_data ad; 4120 char *addrp; 4121 u8 secmark_active; 4122 u8 peerlbl_active; 4123 4124 if (family != PF_INET && family != PF_INET6) 4125 return 0; 4126 4127 /* Handle mapped IPv4 packets arriving via IPv6 sockets */ 4128 if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP)) 4129 family = PF_INET; 4130 4131 /* If any sort of compatibility mode is enabled then handoff processing 4132 * to the selinux_sock_rcv_skb_compat() function to deal with the 4133 * special handling. We do this in an attempt to keep this function 4134 * as fast and as clean as possible. */ 4135 if (!selinux_policycap_netpeer) 4136 return selinux_sock_rcv_skb_compat(sk, skb, family); 4137 4138 secmark_active = selinux_secmark_enabled(); 4139 peerlbl_active = netlbl_enabled() || selinux_xfrm_enabled(); 4140 if (!secmark_active && !peerlbl_active) 4141 return 0; 4142 4143 COMMON_AUDIT_DATA_INIT(&ad, NET); 4144 ad.u.net.netif = skb->skb_iif; 4145 ad.u.net.family = family; 4146 err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL); 4147 if (err) 4148 return err; 4149 4150 if (peerlbl_active) { 4151 u32 peer_sid; 4152 4153 err = selinux_skb_peerlbl_sid(skb, family, &peer_sid); 4154 if (err) 4155 return err; 4156 err = selinux_inet_sys_rcv_skb(skb->skb_iif, addrp, family, 4157 peer_sid, &ad); 4158 if (err) { 4159 selinux_netlbl_err(skb, err, 0); 4160 return err; 4161 } 4162 err = avc_has_perm(sk_sid, peer_sid, SECCLASS_PEER, 4163 PEER__RECV, &ad); 4164 if (err) 4165 selinux_netlbl_err(skb, err, 0); 4166 } 4167 4168 if (secmark_active) { 4169 err = avc_has_perm(sk_sid, skb->secmark, SECCLASS_PACKET, 4170 PACKET__RECV, &ad); 4171 if (err) 4172 return err; 4173 } 4174 4175 return err; 4176 } 4177 4178 static int selinux_socket_getpeersec_stream(struct socket *sock, char __user *optval, 4179 int __user *optlen, unsigned len) 4180 { 4181 int err = 0; 4182 char *scontext; 4183 u32 scontext_len; 4184 struct sk_security_struct *sksec = sock->sk->sk_security; 4185 u32 peer_sid = SECSID_NULL; 4186 4187 if (sksec->sclass == SECCLASS_UNIX_STREAM_SOCKET || 4188 sksec->sclass == SECCLASS_TCP_SOCKET) 4189 peer_sid = sksec->peer_sid; 4190 if (peer_sid == SECSID_NULL) 4191 return -ENOPROTOOPT; 4192 4193 err = security_sid_to_context(peer_sid, &scontext, &scontext_len); 4194 if (err) 4195 return err; 4196 4197 if (scontext_len > len) { 4198 err = -ERANGE; 4199 goto out_len; 4200 } 4201 4202 if (copy_to_user(optval, scontext, scontext_len)) 4203 err = -EFAULT; 4204 4205 out_len: 4206 if (put_user(scontext_len, optlen)) 4207 err = -EFAULT; 4208 kfree(scontext); 4209 return err; 4210 } 4211 4212 static int selinux_socket_getpeersec_dgram(struct socket *sock, struct sk_buff *skb, u32 *secid) 4213 { 4214 u32 peer_secid = SECSID_NULL; 4215 u16 family; 4216 4217 if (skb && skb->protocol == htons(ETH_P_IP)) 4218 family = PF_INET; 4219 else if (skb && skb->protocol == htons(ETH_P_IPV6)) 4220 family = PF_INET6; 4221 else if (sock) 4222 family = sock->sk->sk_family; 4223 else 4224 goto out; 4225 4226 if (sock && family == PF_UNIX) 4227 selinux_inode_getsecid(SOCK_INODE(sock), &peer_secid); 4228 else if (skb) 4229 selinux_skb_peerlbl_sid(skb, family, &peer_secid); 4230 4231 out: 4232 *secid = peer_secid; 4233 if (peer_secid == SECSID_NULL) 4234 return -EINVAL; 4235 return 0; 4236 } 4237 4238 static int selinux_sk_alloc_security(struct sock *sk, int family, gfp_t priority) 4239 { 4240 struct sk_security_struct *sksec; 4241 4242 sksec = kzalloc(sizeof(*sksec), priority); 4243 if (!sksec) 4244 return -ENOMEM; 4245 4246 sksec->peer_sid = SECINITSID_UNLABELED; 4247 sksec->sid = SECINITSID_UNLABELED; 4248 selinux_netlbl_sk_security_reset(sksec); 4249 sk->sk_security = sksec; 4250 4251 return 0; 4252 } 4253 4254 static void selinux_sk_free_security(struct sock *sk) 4255 { 4256 struct sk_security_struct *sksec = sk->sk_security; 4257 4258 sk->sk_security = NULL; 4259 selinux_netlbl_sk_security_free(sksec); 4260 kfree(sksec); 4261 } 4262 4263 static void selinux_sk_clone_security(const struct sock *sk, struct sock *newsk) 4264 { 4265 struct sk_security_struct *sksec = sk->sk_security; 4266 struct sk_security_struct *newsksec = newsk->sk_security; 4267 4268 newsksec->sid = sksec->sid; 4269 newsksec->peer_sid = sksec->peer_sid; 4270 newsksec->sclass = sksec->sclass; 4271 4272 selinux_netlbl_sk_security_reset(newsksec); 4273 } 4274 4275 static void selinux_sk_getsecid(struct sock *sk, u32 *secid) 4276 { 4277 if (!sk) 4278 *secid = SECINITSID_ANY_SOCKET; 4279 else { 4280 struct sk_security_struct *sksec = sk->sk_security; 4281 4282 *secid = sksec->sid; 4283 } 4284 } 4285 4286 static void selinux_sock_graft(struct sock *sk, struct socket *parent) 4287 { 4288 struct inode_security_struct *isec = SOCK_INODE(parent)->i_security; 4289 struct sk_security_struct *sksec = sk->sk_security; 4290 4291 if (sk->sk_family == PF_INET || sk->sk_family == PF_INET6 || 4292 sk->sk_family == PF_UNIX) 4293 isec->sid = sksec->sid; 4294 sksec->sclass = isec->sclass; 4295 } 4296 4297 static int selinux_inet_conn_request(struct sock *sk, struct sk_buff *skb, 4298 struct request_sock *req) 4299 { 4300 struct sk_security_struct *sksec = sk->sk_security; 4301 int err; 4302 u16 family = sk->sk_family; 4303 u32 newsid; 4304 u32 peersid; 4305 4306 /* handle mapped IPv4 packets arriving via IPv6 sockets */ 4307 if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP)) 4308 family = PF_INET; 4309 4310 err = selinux_skb_peerlbl_sid(skb, family, &peersid); 4311 if (err) 4312 return err; 4313 if (peersid == SECSID_NULL) { 4314 req->secid = sksec->sid; 4315 req->peer_secid = SECSID_NULL; 4316 } else { 4317 err = security_sid_mls_copy(sksec->sid, peersid, &newsid); 4318 if (err) 4319 return err; 4320 req->secid = newsid; 4321 req->peer_secid = peersid; 4322 } 4323 4324 return selinux_netlbl_inet_conn_request(req, family); 4325 } 4326 4327 static void selinux_inet_csk_clone(struct sock *newsk, 4328 const struct request_sock *req) 4329 { 4330 struct sk_security_struct *newsksec = newsk->sk_security; 4331 4332 newsksec->sid = req->secid; 4333 newsksec->peer_sid = req->peer_secid; 4334 /* NOTE: Ideally, we should also get the isec->sid for the 4335 new socket in sync, but we don't have the isec available yet. 4336 So we will wait until sock_graft to do it, by which 4337 time it will have been created and available. */ 4338 4339 /* We don't need to take any sort of lock here as we are the only 4340 * thread with access to newsksec */ 4341 selinux_netlbl_inet_csk_clone(newsk, req->rsk_ops->family); 4342 } 4343 4344 static void selinux_inet_conn_established(struct sock *sk, struct sk_buff *skb) 4345 { 4346 u16 family = sk->sk_family; 4347 struct sk_security_struct *sksec = sk->sk_security; 4348 4349 /* handle mapped IPv4 packets arriving via IPv6 sockets */ 4350 if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP)) 4351 family = PF_INET; 4352 4353 selinux_skb_peerlbl_sid(skb, family, &sksec->peer_sid); 4354 } 4355 4356 static int selinux_secmark_relabel_packet(u32 sid) 4357 { 4358 const struct task_security_struct *__tsec; 4359 u32 tsid; 4360 4361 __tsec = current_security(); 4362 tsid = __tsec->sid; 4363 4364 return avc_has_perm(tsid, sid, SECCLASS_PACKET, PACKET__RELABELTO, NULL); 4365 } 4366 4367 static void selinux_secmark_refcount_inc(void) 4368 { 4369 atomic_inc(&selinux_secmark_refcount); 4370 } 4371 4372 static void selinux_secmark_refcount_dec(void) 4373 { 4374 atomic_dec(&selinux_secmark_refcount); 4375 } 4376 4377 static void selinux_req_classify_flow(const struct request_sock *req, 4378 struct flowi *fl) 4379 { 4380 fl->flowi_secid = req->secid; 4381 } 4382 4383 static int selinux_tun_dev_create(void) 4384 { 4385 u32 sid = current_sid(); 4386 4387 /* we aren't taking into account the "sockcreate" SID since the socket 4388 * that is being created here is not a socket in the traditional sense, 4389 * instead it is a private sock, accessible only to the kernel, and 4390 * representing a wide range of network traffic spanning multiple 4391 * connections unlike traditional sockets - check the TUN driver to 4392 * get a better understanding of why this socket is special */ 4393 4394 return avc_has_perm(sid, sid, SECCLASS_TUN_SOCKET, TUN_SOCKET__CREATE, 4395 NULL); 4396 } 4397 4398 static void selinux_tun_dev_post_create(struct sock *sk) 4399 { 4400 struct sk_security_struct *sksec = sk->sk_security; 4401 4402 /* we don't currently perform any NetLabel based labeling here and it 4403 * isn't clear that we would want to do so anyway; while we could apply 4404 * labeling without the support of the TUN user the resulting labeled 4405 * traffic from the other end of the connection would almost certainly 4406 * cause confusion to the TUN user that had no idea network labeling 4407 * protocols were being used */ 4408 4409 /* see the comments in selinux_tun_dev_create() about why we don't use 4410 * the sockcreate SID here */ 4411 4412 sksec->sid = current_sid(); 4413 sksec->sclass = SECCLASS_TUN_SOCKET; 4414 } 4415 4416 static int selinux_tun_dev_attach(struct sock *sk) 4417 { 4418 struct sk_security_struct *sksec = sk->sk_security; 4419 u32 sid = current_sid(); 4420 int err; 4421 4422 err = avc_has_perm(sid, sksec->sid, SECCLASS_TUN_SOCKET, 4423 TUN_SOCKET__RELABELFROM, NULL); 4424 if (err) 4425 return err; 4426 err = avc_has_perm(sid, sid, SECCLASS_TUN_SOCKET, 4427 TUN_SOCKET__RELABELTO, NULL); 4428 if (err) 4429 return err; 4430 4431 sksec->sid = sid; 4432 4433 return 0; 4434 } 4435 4436 static int selinux_nlmsg_perm(struct sock *sk, struct sk_buff *skb) 4437 { 4438 int err = 0; 4439 u32 perm; 4440 struct nlmsghdr *nlh; 4441 struct sk_security_struct *sksec = sk->sk_security; 4442 4443 if (skb->len < NLMSG_SPACE(0)) { 4444 err = -EINVAL; 4445 goto out; 4446 } 4447 nlh = nlmsg_hdr(skb); 4448 4449 err = selinux_nlmsg_lookup(sksec->sclass, nlh->nlmsg_type, &perm); 4450 if (err) { 4451 if (err == -EINVAL) { 4452 audit_log(current->audit_context, GFP_KERNEL, AUDIT_SELINUX_ERR, 4453 "SELinux: unrecognized netlink message" 4454 " type=%hu for sclass=%hu\n", 4455 nlh->nlmsg_type, sksec->sclass); 4456 if (!selinux_enforcing || security_get_allow_unknown()) 4457 err = 0; 4458 } 4459 4460 /* Ignore */ 4461 if (err == -ENOENT) 4462 err = 0; 4463 goto out; 4464 } 4465 4466 err = sock_has_perm(current, sk, perm); 4467 out: 4468 return err; 4469 } 4470 4471 #ifdef CONFIG_NETFILTER 4472 4473 static unsigned int selinux_ip_forward(struct sk_buff *skb, int ifindex, 4474 u16 family) 4475 { 4476 int err; 4477 char *addrp; 4478 u32 peer_sid; 4479 struct common_audit_data ad; 4480 u8 secmark_active; 4481 u8 netlbl_active; 4482 u8 peerlbl_active; 4483 4484 if (!selinux_policycap_netpeer) 4485 return NF_ACCEPT; 4486 4487 secmark_active = selinux_secmark_enabled(); 4488 netlbl_active = netlbl_enabled(); 4489 peerlbl_active = netlbl_active || selinux_xfrm_enabled(); 4490 if (!secmark_active && !peerlbl_active) 4491 return NF_ACCEPT; 4492 4493 if (selinux_skb_peerlbl_sid(skb, family, &peer_sid) != 0) 4494 return NF_DROP; 4495 4496 COMMON_AUDIT_DATA_INIT(&ad, NET); 4497 ad.u.net.netif = ifindex; 4498 ad.u.net.family = family; 4499 if (selinux_parse_skb(skb, &ad, &addrp, 1, NULL) != 0) 4500 return NF_DROP; 4501 4502 if (peerlbl_active) { 4503 err = selinux_inet_sys_rcv_skb(ifindex, addrp, family, 4504 peer_sid, &ad); 4505 if (err) { 4506 selinux_netlbl_err(skb, err, 1); 4507 return NF_DROP; 4508 } 4509 } 4510 4511 if (secmark_active) 4512 if (avc_has_perm(peer_sid, skb->secmark, 4513 SECCLASS_PACKET, PACKET__FORWARD_IN, &ad)) 4514 return NF_DROP; 4515 4516 if (netlbl_active) 4517 /* we do this in the FORWARD path and not the POST_ROUTING 4518 * path because we want to make sure we apply the necessary 4519 * labeling before IPsec is applied so we can leverage AH 4520 * protection */ 4521 if (selinux_netlbl_skbuff_setsid(skb, family, peer_sid) != 0) 4522 return NF_DROP; 4523 4524 return NF_ACCEPT; 4525 } 4526 4527 static unsigned int selinux_ipv4_forward(unsigned int hooknum, 4528 struct sk_buff *skb, 4529 const struct net_device *in, 4530 const struct net_device *out, 4531 int (*okfn)(struct sk_buff *)) 4532 { 4533 return selinux_ip_forward(skb, in->ifindex, PF_INET); 4534 } 4535 4536 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE) 4537 static unsigned int selinux_ipv6_forward(unsigned int hooknum, 4538 struct sk_buff *skb, 4539 const struct net_device *in, 4540 const struct net_device *out, 4541 int (*okfn)(struct sk_buff *)) 4542 { 4543 return selinux_ip_forward(skb, in->ifindex, PF_INET6); 4544 } 4545 #endif /* IPV6 */ 4546 4547 static unsigned int selinux_ip_output(struct sk_buff *skb, 4548 u16 family) 4549 { 4550 u32 sid; 4551 4552 if (!netlbl_enabled()) 4553 return NF_ACCEPT; 4554 4555 /* we do this in the LOCAL_OUT path and not the POST_ROUTING path 4556 * because we want to make sure we apply the necessary labeling 4557 * before IPsec is applied so we can leverage AH protection */ 4558 if (skb->sk) { 4559 struct sk_security_struct *sksec = skb->sk->sk_security; 4560 sid = sksec->sid; 4561 } else 4562 sid = SECINITSID_KERNEL; 4563 if (selinux_netlbl_skbuff_setsid(skb, family, sid) != 0) 4564 return NF_DROP; 4565 4566 return NF_ACCEPT; 4567 } 4568 4569 static unsigned int selinux_ipv4_output(unsigned int hooknum, 4570 struct sk_buff *skb, 4571 const struct net_device *in, 4572 const struct net_device *out, 4573 int (*okfn)(struct sk_buff *)) 4574 { 4575 return selinux_ip_output(skb, PF_INET); 4576 } 4577 4578 static unsigned int selinux_ip_postroute_compat(struct sk_buff *skb, 4579 int ifindex, 4580 u16 family) 4581 { 4582 struct sock *sk = skb->sk; 4583 struct sk_security_struct *sksec; 4584 struct common_audit_data ad; 4585 char *addrp; 4586 u8 proto; 4587 4588 if (sk == NULL) 4589 return NF_ACCEPT; 4590 sksec = sk->sk_security; 4591 4592 COMMON_AUDIT_DATA_INIT(&ad, NET); 4593 ad.u.net.netif = ifindex; 4594 ad.u.net.family = family; 4595 if (selinux_parse_skb(skb, &ad, &addrp, 0, &proto)) 4596 return NF_DROP; 4597 4598 if (selinux_secmark_enabled()) 4599 if (avc_has_perm(sksec->sid, skb->secmark, 4600 SECCLASS_PACKET, PACKET__SEND, &ad)) 4601 return NF_DROP_ERR(-ECONNREFUSED); 4602 4603 if (selinux_xfrm_postroute_last(sksec->sid, skb, &ad, proto)) 4604 return NF_DROP_ERR(-ECONNREFUSED); 4605 4606 return NF_ACCEPT; 4607 } 4608 4609 static unsigned int selinux_ip_postroute(struct sk_buff *skb, int ifindex, 4610 u16 family) 4611 { 4612 u32 secmark_perm; 4613 u32 peer_sid; 4614 struct sock *sk; 4615 struct common_audit_data ad; 4616 char *addrp; 4617 u8 secmark_active; 4618 u8 peerlbl_active; 4619 4620 /* If any sort of compatibility mode is enabled then handoff processing 4621 * to the selinux_ip_postroute_compat() function to deal with the 4622 * special handling. We do this in an attempt to keep this function 4623 * as fast and as clean as possible. */ 4624 if (!selinux_policycap_netpeer) 4625 return selinux_ip_postroute_compat(skb, ifindex, family); 4626 #ifdef CONFIG_XFRM 4627 /* If skb->dst->xfrm is non-NULL then the packet is undergoing an IPsec 4628 * packet transformation so allow the packet to pass without any checks 4629 * since we'll have another chance to perform access control checks 4630 * when the packet is on it's final way out. 4631 * NOTE: there appear to be some IPv6 multicast cases where skb->dst 4632 * is NULL, in this case go ahead and apply access control. */ 4633 if (skb_dst(skb) != NULL && skb_dst(skb)->xfrm != NULL) 4634 return NF_ACCEPT; 4635 #endif 4636 secmark_active = selinux_secmark_enabled(); 4637 peerlbl_active = netlbl_enabled() || selinux_xfrm_enabled(); 4638 if (!secmark_active && !peerlbl_active) 4639 return NF_ACCEPT; 4640 4641 /* if the packet is being forwarded then get the peer label from the 4642 * packet itself; otherwise check to see if it is from a local 4643 * application or the kernel, if from an application get the peer label 4644 * from the sending socket, otherwise use the kernel's sid */ 4645 sk = skb->sk; 4646 if (sk == NULL) { 4647 if (skb->skb_iif) { 4648 secmark_perm = PACKET__FORWARD_OUT; 4649 if (selinux_skb_peerlbl_sid(skb, family, &peer_sid)) 4650 return NF_DROP; 4651 } else { 4652 secmark_perm = PACKET__SEND; 4653 peer_sid = SECINITSID_KERNEL; 4654 } 4655 } else { 4656 struct sk_security_struct *sksec = sk->sk_security; 4657 peer_sid = sksec->sid; 4658 secmark_perm = PACKET__SEND; 4659 } 4660 4661 COMMON_AUDIT_DATA_INIT(&ad, NET); 4662 ad.u.net.netif = ifindex; 4663 ad.u.net.family = family; 4664 if (selinux_parse_skb(skb, &ad, &addrp, 0, NULL)) 4665 return NF_DROP; 4666 4667 if (secmark_active) 4668 if (avc_has_perm(peer_sid, skb->secmark, 4669 SECCLASS_PACKET, secmark_perm, &ad)) 4670 return NF_DROP_ERR(-ECONNREFUSED); 4671 4672 if (peerlbl_active) { 4673 u32 if_sid; 4674 u32 node_sid; 4675 4676 if (sel_netif_sid(ifindex, &if_sid)) 4677 return NF_DROP; 4678 if (avc_has_perm(peer_sid, if_sid, 4679 SECCLASS_NETIF, NETIF__EGRESS, &ad)) 4680 return NF_DROP_ERR(-ECONNREFUSED); 4681 4682 if (sel_netnode_sid(addrp, family, &node_sid)) 4683 return NF_DROP; 4684 if (avc_has_perm(peer_sid, node_sid, 4685 SECCLASS_NODE, NODE__SENDTO, &ad)) 4686 return NF_DROP_ERR(-ECONNREFUSED); 4687 } 4688 4689 return NF_ACCEPT; 4690 } 4691 4692 static unsigned int selinux_ipv4_postroute(unsigned int hooknum, 4693 struct sk_buff *skb, 4694 const struct net_device *in, 4695 const struct net_device *out, 4696 int (*okfn)(struct sk_buff *)) 4697 { 4698 return selinux_ip_postroute(skb, out->ifindex, PF_INET); 4699 } 4700 4701 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE) 4702 static unsigned int selinux_ipv6_postroute(unsigned int hooknum, 4703 struct sk_buff *skb, 4704 const struct net_device *in, 4705 const struct net_device *out, 4706 int (*okfn)(struct sk_buff *)) 4707 { 4708 return selinux_ip_postroute(skb, out->ifindex, PF_INET6); 4709 } 4710 #endif /* IPV6 */ 4711 4712 #endif /* CONFIG_NETFILTER */ 4713 4714 static int selinux_netlink_send(struct sock *sk, struct sk_buff *skb) 4715 { 4716 int err; 4717 4718 err = cap_netlink_send(sk, skb); 4719 if (err) 4720 return err; 4721 4722 return selinux_nlmsg_perm(sk, skb); 4723 } 4724 4725 static int selinux_netlink_recv(struct sk_buff *skb, int capability) 4726 { 4727 int err; 4728 struct common_audit_data ad; 4729 u32 sid; 4730 4731 err = cap_netlink_recv(skb, capability); 4732 if (err) 4733 return err; 4734 4735 COMMON_AUDIT_DATA_INIT(&ad, CAP); 4736 ad.u.cap = capability; 4737 4738 security_task_getsecid(current, &sid); 4739 return avc_has_perm(sid, sid, SECCLASS_CAPABILITY, 4740 CAP_TO_MASK(capability), &ad); 4741 } 4742 4743 static int ipc_alloc_security(struct task_struct *task, 4744 struct kern_ipc_perm *perm, 4745 u16 sclass) 4746 { 4747 struct ipc_security_struct *isec; 4748 u32 sid; 4749 4750 isec = kzalloc(sizeof(struct ipc_security_struct), GFP_KERNEL); 4751 if (!isec) 4752 return -ENOMEM; 4753 4754 sid = task_sid(task); 4755 isec->sclass = sclass; 4756 isec->sid = sid; 4757 perm->security = isec; 4758 4759 return 0; 4760 } 4761 4762 static void ipc_free_security(struct kern_ipc_perm *perm) 4763 { 4764 struct ipc_security_struct *isec = perm->security; 4765 perm->security = NULL; 4766 kfree(isec); 4767 } 4768 4769 static int msg_msg_alloc_security(struct msg_msg *msg) 4770 { 4771 struct msg_security_struct *msec; 4772 4773 msec = kzalloc(sizeof(struct msg_security_struct), GFP_KERNEL); 4774 if (!msec) 4775 return -ENOMEM; 4776 4777 msec->sid = SECINITSID_UNLABELED; 4778 msg->security = msec; 4779 4780 return 0; 4781 } 4782 4783 static void msg_msg_free_security(struct msg_msg *msg) 4784 { 4785 struct msg_security_struct *msec = msg->security; 4786 4787 msg->security = NULL; 4788 kfree(msec); 4789 } 4790 4791 static int ipc_has_perm(struct kern_ipc_perm *ipc_perms, 4792 u32 perms) 4793 { 4794 struct ipc_security_struct *isec; 4795 struct common_audit_data ad; 4796 u32 sid = current_sid(); 4797 4798 isec = ipc_perms->security; 4799 4800 COMMON_AUDIT_DATA_INIT(&ad, IPC); 4801 ad.u.ipc_id = ipc_perms->key; 4802 4803 return avc_has_perm(sid, isec->sid, isec->sclass, perms, &ad); 4804 } 4805 4806 static int selinux_msg_msg_alloc_security(struct msg_msg *msg) 4807 { 4808 return msg_msg_alloc_security(msg); 4809 } 4810 4811 static void selinux_msg_msg_free_security(struct msg_msg *msg) 4812 { 4813 msg_msg_free_security(msg); 4814 } 4815 4816 /* message queue security operations */ 4817 static int selinux_msg_queue_alloc_security(struct msg_queue *msq) 4818 { 4819 struct ipc_security_struct *isec; 4820 struct common_audit_data ad; 4821 u32 sid = current_sid(); 4822 int rc; 4823 4824 rc = ipc_alloc_security(current, &msq->q_perm, SECCLASS_MSGQ); 4825 if (rc) 4826 return rc; 4827 4828 isec = msq->q_perm.security; 4829 4830 COMMON_AUDIT_DATA_INIT(&ad, IPC); 4831 ad.u.ipc_id = msq->q_perm.key; 4832 4833 rc = avc_has_perm(sid, isec->sid, SECCLASS_MSGQ, 4834 MSGQ__CREATE, &ad); 4835 if (rc) { 4836 ipc_free_security(&msq->q_perm); 4837 return rc; 4838 } 4839 return 0; 4840 } 4841 4842 static void selinux_msg_queue_free_security(struct msg_queue *msq) 4843 { 4844 ipc_free_security(&msq->q_perm); 4845 } 4846 4847 static int selinux_msg_queue_associate(struct msg_queue *msq, int msqflg) 4848 { 4849 struct ipc_security_struct *isec; 4850 struct common_audit_data ad; 4851 u32 sid = current_sid(); 4852 4853 isec = msq->q_perm.security; 4854 4855 COMMON_AUDIT_DATA_INIT(&ad, IPC); 4856 ad.u.ipc_id = msq->q_perm.key; 4857 4858 return avc_has_perm(sid, isec->sid, SECCLASS_MSGQ, 4859 MSGQ__ASSOCIATE, &ad); 4860 } 4861 4862 static int selinux_msg_queue_msgctl(struct msg_queue *msq, int cmd) 4863 { 4864 int err; 4865 int perms; 4866 4867 switch (cmd) { 4868 case IPC_INFO: 4869 case MSG_INFO: 4870 /* No specific object, just general system-wide information. */ 4871 return task_has_system(current, SYSTEM__IPC_INFO); 4872 case IPC_STAT: 4873 case MSG_STAT: 4874 perms = MSGQ__GETATTR | MSGQ__ASSOCIATE; 4875 break; 4876 case IPC_SET: 4877 perms = MSGQ__SETATTR; 4878 break; 4879 case IPC_RMID: 4880 perms = MSGQ__DESTROY; 4881 break; 4882 default: 4883 return 0; 4884 } 4885 4886 err = ipc_has_perm(&msq->q_perm, perms); 4887 return err; 4888 } 4889 4890 static int selinux_msg_queue_msgsnd(struct msg_queue *msq, struct msg_msg *msg, int msqflg) 4891 { 4892 struct ipc_security_struct *isec; 4893 struct msg_security_struct *msec; 4894 struct common_audit_data ad; 4895 u32 sid = current_sid(); 4896 int rc; 4897 4898 isec = msq->q_perm.security; 4899 msec = msg->security; 4900 4901 /* 4902 * First time through, need to assign label to the message 4903 */ 4904 if (msec->sid == SECINITSID_UNLABELED) { 4905 /* 4906 * Compute new sid based on current process and 4907 * message queue this message will be stored in 4908 */ 4909 rc = security_transition_sid(sid, isec->sid, SECCLASS_MSG, 4910 NULL, &msec->sid); 4911 if (rc) 4912 return rc; 4913 } 4914 4915 COMMON_AUDIT_DATA_INIT(&ad, IPC); 4916 ad.u.ipc_id = msq->q_perm.key; 4917 4918 /* Can this process write to the queue? */ 4919 rc = avc_has_perm(sid, isec->sid, SECCLASS_MSGQ, 4920 MSGQ__WRITE, &ad); 4921 if (!rc) 4922 /* Can this process send the message */ 4923 rc = avc_has_perm(sid, msec->sid, SECCLASS_MSG, 4924 MSG__SEND, &ad); 4925 if (!rc) 4926 /* Can the message be put in the queue? */ 4927 rc = avc_has_perm(msec->sid, isec->sid, SECCLASS_MSGQ, 4928 MSGQ__ENQUEUE, &ad); 4929 4930 return rc; 4931 } 4932 4933 static int selinux_msg_queue_msgrcv(struct msg_queue *msq, struct msg_msg *msg, 4934 struct task_struct *target, 4935 long type, int mode) 4936 { 4937 struct ipc_security_struct *isec; 4938 struct msg_security_struct *msec; 4939 struct common_audit_data ad; 4940 u32 sid = task_sid(target); 4941 int rc; 4942 4943 isec = msq->q_perm.security; 4944 msec = msg->security; 4945 4946 COMMON_AUDIT_DATA_INIT(&ad, IPC); 4947 ad.u.ipc_id = msq->q_perm.key; 4948 4949 rc = avc_has_perm(sid, isec->sid, 4950 SECCLASS_MSGQ, MSGQ__READ, &ad); 4951 if (!rc) 4952 rc = avc_has_perm(sid, msec->sid, 4953 SECCLASS_MSG, MSG__RECEIVE, &ad); 4954 return rc; 4955 } 4956 4957 /* Shared Memory security operations */ 4958 static int selinux_shm_alloc_security(struct shmid_kernel *shp) 4959 { 4960 struct ipc_security_struct *isec; 4961 struct common_audit_data ad; 4962 u32 sid = current_sid(); 4963 int rc; 4964 4965 rc = ipc_alloc_security(current, &shp->shm_perm, SECCLASS_SHM); 4966 if (rc) 4967 return rc; 4968 4969 isec = shp->shm_perm.security; 4970 4971 COMMON_AUDIT_DATA_INIT(&ad, IPC); 4972 ad.u.ipc_id = shp->shm_perm.key; 4973 4974 rc = avc_has_perm(sid, isec->sid, SECCLASS_SHM, 4975 SHM__CREATE, &ad); 4976 if (rc) { 4977 ipc_free_security(&shp->shm_perm); 4978 return rc; 4979 } 4980 return 0; 4981 } 4982 4983 static void selinux_shm_free_security(struct shmid_kernel *shp) 4984 { 4985 ipc_free_security(&shp->shm_perm); 4986 } 4987 4988 static int selinux_shm_associate(struct shmid_kernel *shp, int shmflg) 4989 { 4990 struct ipc_security_struct *isec; 4991 struct common_audit_data ad; 4992 u32 sid = current_sid(); 4993 4994 isec = shp->shm_perm.security; 4995 4996 COMMON_AUDIT_DATA_INIT(&ad, IPC); 4997 ad.u.ipc_id = shp->shm_perm.key; 4998 4999 return avc_has_perm(sid, isec->sid, SECCLASS_SHM, 5000 SHM__ASSOCIATE, &ad); 5001 } 5002 5003 /* Note, at this point, shp is locked down */ 5004 static int selinux_shm_shmctl(struct shmid_kernel *shp, int cmd) 5005 { 5006 int perms; 5007 int err; 5008 5009 switch (cmd) { 5010 case IPC_INFO: 5011 case SHM_INFO: 5012 /* No specific object, just general system-wide information. */ 5013 return task_has_system(current, SYSTEM__IPC_INFO); 5014 case IPC_STAT: 5015 case SHM_STAT: 5016 perms = SHM__GETATTR | SHM__ASSOCIATE; 5017 break; 5018 case IPC_SET: 5019 perms = SHM__SETATTR; 5020 break; 5021 case SHM_LOCK: 5022 case SHM_UNLOCK: 5023 perms = SHM__LOCK; 5024 break; 5025 case IPC_RMID: 5026 perms = SHM__DESTROY; 5027 break; 5028 default: 5029 return 0; 5030 } 5031 5032 err = ipc_has_perm(&shp->shm_perm, perms); 5033 return err; 5034 } 5035 5036 static int selinux_shm_shmat(struct shmid_kernel *shp, 5037 char __user *shmaddr, int shmflg) 5038 { 5039 u32 perms; 5040 5041 if (shmflg & SHM_RDONLY) 5042 perms = SHM__READ; 5043 else 5044 perms = SHM__READ | SHM__WRITE; 5045 5046 return ipc_has_perm(&shp->shm_perm, perms); 5047 } 5048 5049 /* Semaphore security operations */ 5050 static int selinux_sem_alloc_security(struct sem_array *sma) 5051 { 5052 struct ipc_security_struct *isec; 5053 struct common_audit_data ad; 5054 u32 sid = current_sid(); 5055 int rc; 5056 5057 rc = ipc_alloc_security(current, &sma->sem_perm, SECCLASS_SEM); 5058 if (rc) 5059 return rc; 5060 5061 isec = sma->sem_perm.security; 5062 5063 COMMON_AUDIT_DATA_INIT(&ad, IPC); 5064 ad.u.ipc_id = sma->sem_perm.key; 5065 5066 rc = avc_has_perm(sid, isec->sid, SECCLASS_SEM, 5067 SEM__CREATE, &ad); 5068 if (rc) { 5069 ipc_free_security(&sma->sem_perm); 5070 return rc; 5071 } 5072 return 0; 5073 } 5074 5075 static void selinux_sem_free_security(struct sem_array *sma) 5076 { 5077 ipc_free_security(&sma->sem_perm); 5078 } 5079 5080 static int selinux_sem_associate(struct sem_array *sma, int semflg) 5081 { 5082 struct ipc_security_struct *isec; 5083 struct common_audit_data ad; 5084 u32 sid = current_sid(); 5085 5086 isec = sma->sem_perm.security; 5087 5088 COMMON_AUDIT_DATA_INIT(&ad, IPC); 5089 ad.u.ipc_id = sma->sem_perm.key; 5090 5091 return avc_has_perm(sid, isec->sid, SECCLASS_SEM, 5092 SEM__ASSOCIATE, &ad); 5093 } 5094 5095 /* Note, at this point, sma is locked down */ 5096 static int selinux_sem_semctl(struct sem_array *sma, int cmd) 5097 { 5098 int err; 5099 u32 perms; 5100 5101 switch (cmd) { 5102 case IPC_INFO: 5103 case SEM_INFO: 5104 /* No specific object, just general system-wide information. */ 5105 return task_has_system(current, SYSTEM__IPC_INFO); 5106 case GETPID: 5107 case GETNCNT: 5108 case GETZCNT: 5109 perms = SEM__GETATTR; 5110 break; 5111 case GETVAL: 5112 case GETALL: 5113 perms = SEM__READ; 5114 break; 5115 case SETVAL: 5116 case SETALL: 5117 perms = SEM__WRITE; 5118 break; 5119 case IPC_RMID: 5120 perms = SEM__DESTROY; 5121 break; 5122 case IPC_SET: 5123 perms = SEM__SETATTR; 5124 break; 5125 case IPC_STAT: 5126 case SEM_STAT: 5127 perms = SEM__GETATTR | SEM__ASSOCIATE; 5128 break; 5129 default: 5130 return 0; 5131 } 5132 5133 err = ipc_has_perm(&sma->sem_perm, perms); 5134 return err; 5135 } 5136 5137 static int selinux_sem_semop(struct sem_array *sma, 5138 struct sembuf *sops, unsigned nsops, int alter) 5139 { 5140 u32 perms; 5141 5142 if (alter) 5143 perms = SEM__READ | SEM__WRITE; 5144 else 5145 perms = SEM__READ; 5146 5147 return ipc_has_perm(&sma->sem_perm, perms); 5148 } 5149 5150 static int selinux_ipc_permission(struct kern_ipc_perm *ipcp, short flag) 5151 { 5152 u32 av = 0; 5153 5154 av = 0; 5155 if (flag & S_IRUGO) 5156 av |= IPC__UNIX_READ; 5157 if (flag & S_IWUGO) 5158 av |= IPC__UNIX_WRITE; 5159 5160 if (av == 0) 5161 return 0; 5162 5163 return ipc_has_perm(ipcp, av); 5164 } 5165 5166 static void selinux_ipc_getsecid(struct kern_ipc_perm *ipcp, u32 *secid) 5167 { 5168 struct ipc_security_struct *isec = ipcp->security; 5169 *secid = isec->sid; 5170 } 5171 5172 static void selinux_d_instantiate(struct dentry *dentry, struct inode *inode) 5173 { 5174 if (inode) 5175 inode_doinit_with_dentry(inode, dentry); 5176 } 5177 5178 static int selinux_getprocattr(struct task_struct *p, 5179 char *name, char **value) 5180 { 5181 const struct task_security_struct *__tsec; 5182 u32 sid; 5183 int error; 5184 unsigned len; 5185 5186 if (current != p) { 5187 error = current_has_perm(p, PROCESS__GETATTR); 5188 if (error) 5189 return error; 5190 } 5191 5192 rcu_read_lock(); 5193 __tsec = __task_cred(p)->security; 5194 5195 if (!strcmp(name, "current")) 5196 sid = __tsec->sid; 5197 else if (!strcmp(name, "prev")) 5198 sid = __tsec->osid; 5199 else if (!strcmp(name, "exec")) 5200 sid = __tsec->exec_sid; 5201 else if (!strcmp(name, "fscreate")) 5202 sid = __tsec->create_sid; 5203 else if (!strcmp(name, "keycreate")) 5204 sid = __tsec->keycreate_sid; 5205 else if (!strcmp(name, "sockcreate")) 5206 sid = __tsec->sockcreate_sid; 5207 else 5208 goto invalid; 5209 rcu_read_unlock(); 5210 5211 if (!sid) 5212 return 0; 5213 5214 error = security_sid_to_context(sid, value, &len); 5215 if (error) 5216 return error; 5217 return len; 5218 5219 invalid: 5220 rcu_read_unlock(); 5221 return -EINVAL; 5222 } 5223 5224 static int selinux_setprocattr(struct task_struct *p, 5225 char *name, void *value, size_t size) 5226 { 5227 struct task_security_struct *tsec; 5228 struct task_struct *tracer; 5229 struct cred *new; 5230 u32 sid = 0, ptsid; 5231 int error; 5232 char *str = value; 5233 5234 if (current != p) { 5235 /* SELinux only allows a process to change its own 5236 security attributes. */ 5237 return -EACCES; 5238 } 5239 5240 /* 5241 * Basic control over ability to set these attributes at all. 5242 * current == p, but we'll pass them separately in case the 5243 * above restriction is ever removed. 5244 */ 5245 if (!strcmp(name, "exec")) 5246 error = current_has_perm(p, PROCESS__SETEXEC); 5247 else if (!strcmp(name, "fscreate")) 5248 error = current_has_perm(p, PROCESS__SETFSCREATE); 5249 else if (!strcmp(name, "keycreate")) 5250 error = current_has_perm(p, PROCESS__SETKEYCREATE); 5251 else if (!strcmp(name, "sockcreate")) 5252 error = current_has_perm(p, PROCESS__SETSOCKCREATE); 5253 else if (!strcmp(name, "current")) 5254 error = current_has_perm(p, PROCESS__SETCURRENT); 5255 else 5256 error = -EINVAL; 5257 if (error) 5258 return error; 5259 5260 /* Obtain a SID for the context, if one was specified. */ 5261 if (size && str[1] && str[1] != '\n') { 5262 if (str[size-1] == '\n') { 5263 str[size-1] = 0; 5264 size--; 5265 } 5266 error = security_context_to_sid(value, size, &sid); 5267 if (error == -EINVAL && !strcmp(name, "fscreate")) { 5268 if (!capable(CAP_MAC_ADMIN)) 5269 return error; 5270 error = security_context_to_sid_force(value, size, 5271 &sid); 5272 } 5273 if (error) 5274 return error; 5275 } 5276 5277 new = prepare_creds(); 5278 if (!new) 5279 return -ENOMEM; 5280 5281 /* Permission checking based on the specified context is 5282 performed during the actual operation (execve, 5283 open/mkdir/...), when we know the full context of the 5284 operation. See selinux_bprm_set_creds for the execve 5285 checks and may_create for the file creation checks. The 5286 operation will then fail if the context is not permitted. */ 5287 tsec = new->security; 5288 if (!strcmp(name, "exec")) { 5289 tsec->exec_sid = sid; 5290 } else if (!strcmp(name, "fscreate")) { 5291 tsec->create_sid = sid; 5292 } else if (!strcmp(name, "keycreate")) { 5293 error = may_create_key(sid, p); 5294 if (error) 5295 goto abort_change; 5296 tsec->keycreate_sid = sid; 5297 } else if (!strcmp(name, "sockcreate")) { 5298 tsec->sockcreate_sid = sid; 5299 } else if (!strcmp(name, "current")) { 5300 error = -EINVAL; 5301 if (sid == 0) 5302 goto abort_change; 5303 5304 /* Only allow single threaded processes to change context */ 5305 error = -EPERM; 5306 if (!current_is_single_threaded()) { 5307 error = security_bounded_transition(tsec->sid, sid); 5308 if (error) 5309 goto abort_change; 5310 } 5311 5312 /* Check permissions for the transition. */ 5313 error = avc_has_perm(tsec->sid, sid, SECCLASS_PROCESS, 5314 PROCESS__DYNTRANSITION, NULL); 5315 if (error) 5316 goto abort_change; 5317 5318 /* Check for ptracing, and update the task SID if ok. 5319 Otherwise, leave SID unchanged and fail. */ 5320 ptsid = 0; 5321 task_lock(p); 5322 tracer = tracehook_tracer_task(p); 5323 if (tracer) 5324 ptsid = task_sid(tracer); 5325 task_unlock(p); 5326 5327 if (tracer) { 5328 error = avc_has_perm(ptsid, sid, SECCLASS_PROCESS, 5329 PROCESS__PTRACE, NULL); 5330 if (error) 5331 goto abort_change; 5332 } 5333 5334 tsec->sid = sid; 5335 } else { 5336 error = -EINVAL; 5337 goto abort_change; 5338 } 5339 5340 commit_creds(new); 5341 return size; 5342 5343 abort_change: 5344 abort_creds(new); 5345 return error; 5346 } 5347 5348 static int selinux_secid_to_secctx(u32 secid, char **secdata, u32 *seclen) 5349 { 5350 return security_sid_to_context(secid, secdata, seclen); 5351 } 5352 5353 static int selinux_secctx_to_secid(const char *secdata, u32 seclen, u32 *secid) 5354 { 5355 return security_context_to_sid(secdata, seclen, secid); 5356 } 5357 5358 static void selinux_release_secctx(char *secdata, u32 seclen) 5359 { 5360 kfree(secdata); 5361 } 5362 5363 /* 5364 * called with inode->i_mutex locked 5365 */ 5366 static int selinux_inode_notifysecctx(struct inode *inode, void *ctx, u32 ctxlen) 5367 { 5368 return selinux_inode_setsecurity(inode, XATTR_SELINUX_SUFFIX, ctx, ctxlen, 0); 5369 } 5370 5371 /* 5372 * called with inode->i_mutex locked 5373 */ 5374 static int selinux_inode_setsecctx(struct dentry *dentry, void *ctx, u32 ctxlen) 5375 { 5376 return __vfs_setxattr_noperm(dentry, XATTR_NAME_SELINUX, ctx, ctxlen, 0); 5377 } 5378 5379 static int selinux_inode_getsecctx(struct inode *inode, void **ctx, u32 *ctxlen) 5380 { 5381 int len = 0; 5382 len = selinux_inode_getsecurity(inode, XATTR_SELINUX_SUFFIX, 5383 ctx, true); 5384 if (len < 0) 5385 return len; 5386 *ctxlen = len; 5387 return 0; 5388 } 5389 #ifdef CONFIG_KEYS 5390 5391 static int selinux_key_alloc(struct key *k, const struct cred *cred, 5392 unsigned long flags) 5393 { 5394 const struct task_security_struct *tsec; 5395 struct key_security_struct *ksec; 5396 5397 ksec = kzalloc(sizeof(struct key_security_struct), GFP_KERNEL); 5398 if (!ksec) 5399 return -ENOMEM; 5400 5401 tsec = cred->security; 5402 if (tsec->keycreate_sid) 5403 ksec->sid = tsec->keycreate_sid; 5404 else 5405 ksec->sid = tsec->sid; 5406 5407 k->security = ksec; 5408 return 0; 5409 } 5410 5411 static void selinux_key_free(struct key *k) 5412 { 5413 struct key_security_struct *ksec = k->security; 5414 5415 k->security = NULL; 5416 kfree(ksec); 5417 } 5418 5419 static int selinux_key_permission(key_ref_t key_ref, 5420 const struct cred *cred, 5421 key_perm_t perm) 5422 { 5423 struct key *key; 5424 struct key_security_struct *ksec; 5425 u32 sid; 5426 5427 /* if no specific permissions are requested, we skip the 5428 permission check. No serious, additional covert channels 5429 appear to be created. */ 5430 if (perm == 0) 5431 return 0; 5432 5433 sid = cred_sid(cred); 5434 5435 key = key_ref_to_ptr(key_ref); 5436 ksec = key->security; 5437 5438 return avc_has_perm(sid, ksec->sid, SECCLASS_KEY, perm, NULL); 5439 } 5440 5441 static int selinux_key_getsecurity(struct key *key, char **_buffer) 5442 { 5443 struct key_security_struct *ksec = key->security; 5444 char *context = NULL; 5445 unsigned len; 5446 int rc; 5447 5448 rc = security_sid_to_context(ksec->sid, &context, &len); 5449 if (!rc) 5450 rc = len; 5451 *_buffer = context; 5452 return rc; 5453 } 5454 5455 #endif 5456 5457 static struct security_operations selinux_ops = { 5458 .name = "selinux", 5459 5460 .ptrace_access_check = selinux_ptrace_access_check, 5461 .ptrace_traceme = selinux_ptrace_traceme, 5462 .capget = selinux_capget, 5463 .capset = selinux_capset, 5464 .capable = selinux_capable, 5465 .quotactl = selinux_quotactl, 5466 .quota_on = selinux_quota_on, 5467 .syslog = selinux_syslog, 5468 .vm_enough_memory = selinux_vm_enough_memory, 5469 5470 .netlink_send = selinux_netlink_send, 5471 .netlink_recv = selinux_netlink_recv, 5472 5473 .bprm_set_creds = selinux_bprm_set_creds, 5474 .bprm_committing_creds = selinux_bprm_committing_creds, 5475 .bprm_committed_creds = selinux_bprm_committed_creds, 5476 .bprm_secureexec = selinux_bprm_secureexec, 5477 5478 .sb_alloc_security = selinux_sb_alloc_security, 5479 .sb_free_security = selinux_sb_free_security, 5480 .sb_copy_data = selinux_sb_copy_data, 5481 .sb_remount = selinux_sb_remount, 5482 .sb_kern_mount = selinux_sb_kern_mount, 5483 .sb_show_options = selinux_sb_show_options, 5484 .sb_statfs = selinux_sb_statfs, 5485 .sb_mount = selinux_mount, 5486 .sb_umount = selinux_umount, 5487 .sb_set_mnt_opts = selinux_set_mnt_opts, 5488 .sb_clone_mnt_opts = selinux_sb_clone_mnt_opts, 5489 .sb_parse_opts_str = selinux_parse_opts_str, 5490 5491 5492 .inode_alloc_security = selinux_inode_alloc_security, 5493 .inode_free_security = selinux_inode_free_security, 5494 .inode_init_security = selinux_inode_init_security, 5495 .inode_create = selinux_inode_create, 5496 .inode_link = selinux_inode_link, 5497 .inode_unlink = selinux_inode_unlink, 5498 .inode_symlink = selinux_inode_symlink, 5499 .inode_mkdir = selinux_inode_mkdir, 5500 .inode_rmdir = selinux_inode_rmdir, 5501 .inode_mknod = selinux_inode_mknod, 5502 .inode_rename = selinux_inode_rename, 5503 .inode_readlink = selinux_inode_readlink, 5504 .inode_follow_link = selinux_inode_follow_link, 5505 .inode_permission = selinux_inode_permission, 5506 .inode_setattr = selinux_inode_setattr, 5507 .inode_getattr = selinux_inode_getattr, 5508 .inode_setxattr = selinux_inode_setxattr, 5509 .inode_post_setxattr = selinux_inode_post_setxattr, 5510 .inode_getxattr = selinux_inode_getxattr, 5511 .inode_listxattr = selinux_inode_listxattr, 5512 .inode_removexattr = selinux_inode_removexattr, 5513 .inode_getsecurity = selinux_inode_getsecurity, 5514 .inode_setsecurity = selinux_inode_setsecurity, 5515 .inode_listsecurity = selinux_inode_listsecurity, 5516 .inode_getsecid = selinux_inode_getsecid, 5517 5518 .file_permission = selinux_file_permission, 5519 .file_alloc_security = selinux_file_alloc_security, 5520 .file_free_security = selinux_file_free_security, 5521 .file_ioctl = selinux_file_ioctl, 5522 .file_mmap = selinux_file_mmap, 5523 .file_mprotect = selinux_file_mprotect, 5524 .file_lock = selinux_file_lock, 5525 .file_fcntl = selinux_file_fcntl, 5526 .file_set_fowner = selinux_file_set_fowner, 5527 .file_send_sigiotask = selinux_file_send_sigiotask, 5528 .file_receive = selinux_file_receive, 5529 5530 .dentry_open = selinux_dentry_open, 5531 5532 .task_create = selinux_task_create, 5533 .cred_alloc_blank = selinux_cred_alloc_blank, 5534 .cred_free = selinux_cred_free, 5535 .cred_prepare = selinux_cred_prepare, 5536 .cred_transfer = selinux_cred_transfer, 5537 .kernel_act_as = selinux_kernel_act_as, 5538 .kernel_create_files_as = selinux_kernel_create_files_as, 5539 .kernel_module_request = selinux_kernel_module_request, 5540 .task_setpgid = selinux_task_setpgid, 5541 .task_getpgid = selinux_task_getpgid, 5542 .task_getsid = selinux_task_getsid, 5543 .task_getsecid = selinux_task_getsecid, 5544 .task_setnice = selinux_task_setnice, 5545 .task_setioprio = selinux_task_setioprio, 5546 .task_getioprio = selinux_task_getioprio, 5547 .task_setrlimit = selinux_task_setrlimit, 5548 .task_setscheduler = selinux_task_setscheduler, 5549 .task_getscheduler = selinux_task_getscheduler, 5550 .task_movememory = selinux_task_movememory, 5551 .task_kill = selinux_task_kill, 5552 .task_wait = selinux_task_wait, 5553 .task_to_inode = selinux_task_to_inode, 5554 5555 .ipc_permission = selinux_ipc_permission, 5556 .ipc_getsecid = selinux_ipc_getsecid, 5557 5558 .msg_msg_alloc_security = selinux_msg_msg_alloc_security, 5559 .msg_msg_free_security = selinux_msg_msg_free_security, 5560 5561 .msg_queue_alloc_security = selinux_msg_queue_alloc_security, 5562 .msg_queue_free_security = selinux_msg_queue_free_security, 5563 .msg_queue_associate = selinux_msg_queue_associate, 5564 .msg_queue_msgctl = selinux_msg_queue_msgctl, 5565 .msg_queue_msgsnd = selinux_msg_queue_msgsnd, 5566 .msg_queue_msgrcv = selinux_msg_queue_msgrcv, 5567 5568 .shm_alloc_security = selinux_shm_alloc_security, 5569 .shm_free_security = selinux_shm_free_security, 5570 .shm_associate = selinux_shm_associate, 5571 .shm_shmctl = selinux_shm_shmctl, 5572 .shm_shmat = selinux_shm_shmat, 5573 5574 .sem_alloc_security = selinux_sem_alloc_security, 5575 .sem_free_security = selinux_sem_free_security, 5576 .sem_associate = selinux_sem_associate, 5577 .sem_semctl = selinux_sem_semctl, 5578 .sem_semop = selinux_sem_semop, 5579 5580 .d_instantiate = selinux_d_instantiate, 5581 5582 .getprocattr = selinux_getprocattr, 5583 .setprocattr = selinux_setprocattr, 5584 5585 .secid_to_secctx = selinux_secid_to_secctx, 5586 .secctx_to_secid = selinux_secctx_to_secid, 5587 .release_secctx = selinux_release_secctx, 5588 .inode_notifysecctx = selinux_inode_notifysecctx, 5589 .inode_setsecctx = selinux_inode_setsecctx, 5590 .inode_getsecctx = selinux_inode_getsecctx, 5591 5592 .unix_stream_connect = selinux_socket_unix_stream_connect, 5593 .unix_may_send = selinux_socket_unix_may_send, 5594 5595 .socket_create = selinux_socket_create, 5596 .socket_post_create = selinux_socket_post_create, 5597 .socket_bind = selinux_socket_bind, 5598 .socket_connect = selinux_socket_connect, 5599 .socket_listen = selinux_socket_listen, 5600 .socket_accept = selinux_socket_accept, 5601 .socket_sendmsg = selinux_socket_sendmsg, 5602 .socket_recvmsg = selinux_socket_recvmsg, 5603 .socket_getsockname = selinux_socket_getsockname, 5604 .socket_getpeername = selinux_socket_getpeername, 5605 .socket_getsockopt = selinux_socket_getsockopt, 5606 .socket_setsockopt = selinux_socket_setsockopt, 5607 .socket_shutdown = selinux_socket_shutdown, 5608 .socket_sock_rcv_skb = selinux_socket_sock_rcv_skb, 5609 .socket_getpeersec_stream = selinux_socket_getpeersec_stream, 5610 .socket_getpeersec_dgram = selinux_socket_getpeersec_dgram, 5611 .sk_alloc_security = selinux_sk_alloc_security, 5612 .sk_free_security = selinux_sk_free_security, 5613 .sk_clone_security = selinux_sk_clone_security, 5614 .sk_getsecid = selinux_sk_getsecid, 5615 .sock_graft = selinux_sock_graft, 5616 .inet_conn_request = selinux_inet_conn_request, 5617 .inet_csk_clone = selinux_inet_csk_clone, 5618 .inet_conn_established = selinux_inet_conn_established, 5619 .secmark_relabel_packet = selinux_secmark_relabel_packet, 5620 .secmark_refcount_inc = selinux_secmark_refcount_inc, 5621 .secmark_refcount_dec = selinux_secmark_refcount_dec, 5622 .req_classify_flow = selinux_req_classify_flow, 5623 .tun_dev_create = selinux_tun_dev_create, 5624 .tun_dev_post_create = selinux_tun_dev_post_create, 5625 .tun_dev_attach = selinux_tun_dev_attach, 5626 5627 #ifdef CONFIG_SECURITY_NETWORK_XFRM 5628 .xfrm_policy_alloc_security = selinux_xfrm_policy_alloc, 5629 .xfrm_policy_clone_security = selinux_xfrm_policy_clone, 5630 .xfrm_policy_free_security = selinux_xfrm_policy_free, 5631 .xfrm_policy_delete_security = selinux_xfrm_policy_delete, 5632 .xfrm_state_alloc_security = selinux_xfrm_state_alloc, 5633 .xfrm_state_free_security = selinux_xfrm_state_free, 5634 .xfrm_state_delete_security = selinux_xfrm_state_delete, 5635 .xfrm_policy_lookup = selinux_xfrm_policy_lookup, 5636 .xfrm_state_pol_flow_match = selinux_xfrm_state_pol_flow_match, 5637 .xfrm_decode_session = selinux_xfrm_decode_session, 5638 #endif 5639 5640 #ifdef CONFIG_KEYS 5641 .key_alloc = selinux_key_alloc, 5642 .key_free = selinux_key_free, 5643 .key_permission = selinux_key_permission, 5644 .key_getsecurity = selinux_key_getsecurity, 5645 #endif 5646 5647 #ifdef CONFIG_AUDIT 5648 .audit_rule_init = selinux_audit_rule_init, 5649 .audit_rule_known = selinux_audit_rule_known, 5650 .audit_rule_match = selinux_audit_rule_match, 5651 .audit_rule_free = selinux_audit_rule_free, 5652 #endif 5653 }; 5654 5655 static __init int selinux_init(void) 5656 { 5657 if (!security_module_enable(&selinux_ops)) { 5658 selinux_enabled = 0; 5659 return 0; 5660 } 5661 5662 if (!selinux_enabled) { 5663 printk(KERN_INFO "SELinux: Disabled at boot.\n"); 5664 return 0; 5665 } 5666 5667 printk(KERN_INFO "SELinux: Initializing.\n"); 5668 5669 /* Set the security state for the initial task. */ 5670 cred_init_security(); 5671 5672 default_noexec = !(VM_DATA_DEFAULT_FLAGS & VM_EXEC); 5673 5674 sel_inode_cache = kmem_cache_create("selinux_inode_security", 5675 sizeof(struct inode_security_struct), 5676 0, SLAB_PANIC, NULL); 5677 avc_init(); 5678 5679 if (register_security(&selinux_ops)) 5680 panic("SELinux: Unable to register with kernel.\n"); 5681 5682 if (selinux_enforcing) 5683 printk(KERN_DEBUG "SELinux: Starting in enforcing mode\n"); 5684 else 5685 printk(KERN_DEBUG "SELinux: Starting in permissive mode\n"); 5686 5687 return 0; 5688 } 5689 5690 static void delayed_superblock_init(struct super_block *sb, void *unused) 5691 { 5692 superblock_doinit(sb, NULL); 5693 } 5694 5695 void selinux_complete_init(void) 5696 { 5697 printk(KERN_DEBUG "SELinux: Completing initialization.\n"); 5698 5699 /* Set up any superblocks initialized prior to the policy load. */ 5700 printk(KERN_DEBUG "SELinux: Setting up existing superblocks.\n"); 5701 iterate_supers(delayed_superblock_init, NULL); 5702 } 5703 5704 /* SELinux requires early initialization in order to label 5705 all processes and objects when they are created. */ 5706 security_initcall(selinux_init); 5707 5708 #if defined(CONFIG_NETFILTER) 5709 5710 static struct nf_hook_ops selinux_ipv4_ops[] = { 5711 { 5712 .hook = selinux_ipv4_postroute, 5713 .owner = THIS_MODULE, 5714 .pf = PF_INET, 5715 .hooknum = NF_INET_POST_ROUTING, 5716 .priority = NF_IP_PRI_SELINUX_LAST, 5717 }, 5718 { 5719 .hook = selinux_ipv4_forward, 5720 .owner = THIS_MODULE, 5721 .pf = PF_INET, 5722 .hooknum = NF_INET_FORWARD, 5723 .priority = NF_IP_PRI_SELINUX_FIRST, 5724 }, 5725 { 5726 .hook = selinux_ipv4_output, 5727 .owner = THIS_MODULE, 5728 .pf = PF_INET, 5729 .hooknum = NF_INET_LOCAL_OUT, 5730 .priority = NF_IP_PRI_SELINUX_FIRST, 5731 } 5732 }; 5733 5734 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE) 5735 5736 static struct nf_hook_ops selinux_ipv6_ops[] = { 5737 { 5738 .hook = selinux_ipv6_postroute, 5739 .owner = THIS_MODULE, 5740 .pf = PF_INET6, 5741 .hooknum = NF_INET_POST_ROUTING, 5742 .priority = NF_IP6_PRI_SELINUX_LAST, 5743 }, 5744 { 5745 .hook = selinux_ipv6_forward, 5746 .owner = THIS_MODULE, 5747 .pf = PF_INET6, 5748 .hooknum = NF_INET_FORWARD, 5749 .priority = NF_IP6_PRI_SELINUX_FIRST, 5750 } 5751 }; 5752 5753 #endif /* IPV6 */ 5754 5755 static int __init selinux_nf_ip_init(void) 5756 { 5757 int err = 0; 5758 5759 if (!selinux_enabled) 5760 goto out; 5761 5762 printk(KERN_DEBUG "SELinux: Registering netfilter hooks\n"); 5763 5764 err = nf_register_hooks(selinux_ipv4_ops, ARRAY_SIZE(selinux_ipv4_ops)); 5765 if (err) 5766 panic("SELinux: nf_register_hooks for IPv4: error %d\n", err); 5767 5768 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE) 5769 err = nf_register_hooks(selinux_ipv6_ops, ARRAY_SIZE(selinux_ipv6_ops)); 5770 if (err) 5771 panic("SELinux: nf_register_hooks for IPv6: error %d\n", err); 5772 #endif /* IPV6 */ 5773 5774 out: 5775 return err; 5776 } 5777 5778 __initcall(selinux_nf_ip_init); 5779 5780 #ifdef CONFIG_SECURITY_SELINUX_DISABLE 5781 static void selinux_nf_ip_exit(void) 5782 { 5783 printk(KERN_DEBUG "SELinux: Unregistering netfilter hooks\n"); 5784 5785 nf_unregister_hooks(selinux_ipv4_ops, ARRAY_SIZE(selinux_ipv4_ops)); 5786 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE) 5787 nf_unregister_hooks(selinux_ipv6_ops, ARRAY_SIZE(selinux_ipv6_ops)); 5788 #endif /* IPV6 */ 5789 } 5790 #endif 5791 5792 #else /* CONFIG_NETFILTER */ 5793 5794 #ifdef CONFIG_SECURITY_SELINUX_DISABLE 5795 #define selinux_nf_ip_exit() 5796 #endif 5797 5798 #endif /* CONFIG_NETFILTER */ 5799 5800 #ifdef CONFIG_SECURITY_SELINUX_DISABLE 5801 static int selinux_disabled; 5802 5803 int selinux_disable(void) 5804 { 5805 extern void exit_sel_fs(void); 5806 5807 if (ss_initialized) { 5808 /* Not permitted after initial policy load. */ 5809 return -EINVAL; 5810 } 5811 5812 if (selinux_disabled) { 5813 /* Only do this once. */ 5814 return -EINVAL; 5815 } 5816 5817 printk(KERN_INFO "SELinux: Disabled at runtime.\n"); 5818 5819 selinux_disabled = 1; 5820 selinux_enabled = 0; 5821 5822 reset_security_ops(); 5823 5824 /* Try to destroy the avc node cache */ 5825 avc_disable(); 5826 5827 /* Unregister netfilter hooks. */ 5828 selinux_nf_ip_exit(); 5829 5830 /* Unregister selinuxfs. */ 5831 exit_sel_fs(); 5832 5833 return 0; 5834 } 5835 #endif 5836