at v2.6.39 5812 lines 144 kB view raw
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 95extern int selinux_nlmsg_lookup(u16 sclass, u16 nlmsg_type, u32 *perm); 96extern struct security_operations *security_ops; 97 98/* SECMARK reference count */ 99atomic_t selinux_secmark_refcount = ATOMIC_INIT(0); 100 101#ifdef CONFIG_SECURITY_SELINUX_DEVELOP 102int selinux_enforcing; 103 104static 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 115int selinux_enabled = CONFIG_SECURITY_SELINUX_BOOTPARAM_VALUE; 116 117static 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 126int selinux_enabled = 1; 127#endif 128 129static 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 */ 141static 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 */ 149static 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 */ 165static 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 */ 176static 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 */ 189static 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 198static 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 218static 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 232static 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 248static 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 255static 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 275static 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. */ 284extern int ss_initialized; 285 286/* The file system's label must be initialized prior to use. */ 287 288static 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 297static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dentry); 298 299static inline int inode_doinit(struct inode *inode) 300{ 301 return inode_doinit_with_dentry(inode, NULL); 302} 303 304enum { 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 313static 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 324static 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 341static 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 357static 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); 418next_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); 436out: 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 */ 445static 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 526out_free: 527 security_free_mnt_opts(opts); 528 return rc; 529} 530 531static 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 */ 555static 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); 745out: 746 mutex_unlock(&sbsec->lock); 747 return rc; 748out_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 755static 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 812static 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 925out_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 */ 935static 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 952out: 953 rc = selinux_set_mnt_opts(sb, &opts); 954 955out_err: 956 security_free_mnt_opts(&opts); 957 return rc; 958} 959 960static 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 }; 994 /* we need a comma before each option */ 995 seq_putc(m, ','); 996 seq_puts(m, prefix); 997 if (has_comma) 998 seq_putc(m, '\"'); 999 seq_puts(m, opts->mnt_opts[i]); 1000 if (has_comma) 1001 seq_putc(m, '\"'); 1002 } 1003} 1004 1005static int selinux_sb_show_options(struct seq_file *m, struct super_block *sb) 1006{ 1007 struct security_mnt_opts opts; 1008 int rc; 1009 1010 rc = selinux_get_mnt_opts(sb, &opts); 1011 if (rc) { 1012 /* before policy load we may get EINVAL, don't show anything */ 1013 if (rc == -EINVAL) 1014 rc = 0; 1015 return rc; 1016 } 1017 1018 selinux_write_opts(m, &opts); 1019 1020 security_free_mnt_opts(&opts); 1021 1022 return rc; 1023} 1024 1025static inline u16 inode_mode_to_security_class(umode_t mode) 1026{ 1027 switch (mode & S_IFMT) { 1028 case S_IFSOCK: 1029 return SECCLASS_SOCK_FILE; 1030 case S_IFLNK: 1031 return SECCLASS_LNK_FILE; 1032 case S_IFREG: 1033 return SECCLASS_FILE; 1034 case S_IFBLK: 1035 return SECCLASS_BLK_FILE; 1036 case S_IFDIR: 1037 return SECCLASS_DIR; 1038 case S_IFCHR: 1039 return SECCLASS_CHR_FILE; 1040 case S_IFIFO: 1041 return SECCLASS_FIFO_FILE; 1042 1043 } 1044 1045 return SECCLASS_FILE; 1046} 1047 1048static inline int default_protocol_stream(int protocol) 1049{ 1050 return (protocol == IPPROTO_IP || protocol == IPPROTO_TCP); 1051} 1052 1053static inline int default_protocol_dgram(int protocol) 1054{ 1055 return (protocol == IPPROTO_IP || protocol == IPPROTO_UDP); 1056} 1057 1058static inline u16 socket_type_to_security_class(int family, int type, int protocol) 1059{ 1060 switch (family) { 1061 case PF_UNIX: 1062 switch (type) { 1063 case SOCK_STREAM: 1064 case SOCK_SEQPACKET: 1065 return SECCLASS_UNIX_STREAM_SOCKET; 1066 case SOCK_DGRAM: 1067 return SECCLASS_UNIX_DGRAM_SOCKET; 1068 } 1069 break; 1070 case PF_INET: 1071 case PF_INET6: 1072 switch (type) { 1073 case SOCK_STREAM: 1074 if (default_protocol_stream(protocol)) 1075 return SECCLASS_TCP_SOCKET; 1076 else 1077 return SECCLASS_RAWIP_SOCKET; 1078 case SOCK_DGRAM: 1079 if (default_protocol_dgram(protocol)) 1080 return SECCLASS_UDP_SOCKET; 1081 else 1082 return SECCLASS_RAWIP_SOCKET; 1083 case SOCK_DCCP: 1084 return SECCLASS_DCCP_SOCKET; 1085 default: 1086 return SECCLASS_RAWIP_SOCKET; 1087 } 1088 break; 1089 case PF_NETLINK: 1090 switch (protocol) { 1091 case NETLINK_ROUTE: 1092 return SECCLASS_NETLINK_ROUTE_SOCKET; 1093 case NETLINK_FIREWALL: 1094 return SECCLASS_NETLINK_FIREWALL_SOCKET; 1095 case NETLINK_INET_DIAG: 1096 return SECCLASS_NETLINK_TCPDIAG_SOCKET; 1097 case NETLINK_NFLOG: 1098 return SECCLASS_NETLINK_NFLOG_SOCKET; 1099 case NETLINK_XFRM: 1100 return SECCLASS_NETLINK_XFRM_SOCKET; 1101 case NETLINK_SELINUX: 1102 return SECCLASS_NETLINK_SELINUX_SOCKET; 1103 case NETLINK_AUDIT: 1104 return SECCLASS_NETLINK_AUDIT_SOCKET; 1105 case NETLINK_IP6_FW: 1106 return SECCLASS_NETLINK_IP6FW_SOCKET; 1107 case NETLINK_DNRTMSG: 1108 return SECCLASS_NETLINK_DNRT_SOCKET; 1109 case NETLINK_KOBJECT_UEVENT: 1110 return SECCLASS_NETLINK_KOBJECT_UEVENT_SOCKET; 1111 default: 1112 return SECCLASS_NETLINK_SOCKET; 1113 } 1114 case PF_PACKET: 1115 return SECCLASS_PACKET_SOCKET; 1116 case PF_KEY: 1117 return SECCLASS_KEY_SOCKET; 1118 case PF_APPLETALK: 1119 return SECCLASS_APPLETALK_SOCKET; 1120 } 1121 1122 return SECCLASS_SOCKET; 1123} 1124 1125#ifdef CONFIG_PROC_FS 1126static int selinux_proc_get_sid(struct dentry *dentry, 1127 u16 tclass, 1128 u32 *sid) 1129{ 1130 int rc; 1131 char *buffer, *path; 1132 1133 buffer = (char *)__get_free_page(GFP_KERNEL); 1134 if (!buffer) 1135 return -ENOMEM; 1136 1137 path = dentry_path_raw(dentry, buffer, PAGE_SIZE); 1138 if (IS_ERR(path)) 1139 rc = PTR_ERR(path); 1140 else { 1141 /* each process gets a /proc/PID/ entry. Strip off the 1142 * PID part to get a valid selinux labeling. 1143 * e.g. /proc/1/net/rpc/nfs -> /net/rpc/nfs */ 1144 while (path[1] >= '0' && path[1] <= '9') { 1145 path[1] = '/'; 1146 path++; 1147 } 1148 rc = security_genfs_sid("proc", path, tclass, sid); 1149 } 1150 free_page((unsigned long)buffer); 1151 return rc; 1152} 1153#else 1154static int selinux_proc_get_sid(struct dentry *dentry, 1155 u16 tclass, 1156 u32 *sid) 1157{ 1158 return -EINVAL; 1159} 1160#endif 1161 1162/* The inode's security attributes must be initialized before first use. */ 1163static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dentry) 1164{ 1165 struct superblock_security_struct *sbsec = NULL; 1166 struct inode_security_struct *isec = inode->i_security; 1167 u32 sid; 1168 struct dentry *dentry; 1169#define INITCONTEXTLEN 255 1170 char *context = NULL; 1171 unsigned len = 0; 1172 int rc = 0; 1173 1174 if (isec->initialized) 1175 goto out; 1176 1177 mutex_lock(&isec->lock); 1178 if (isec->initialized) 1179 goto out_unlock; 1180 1181 sbsec = inode->i_sb->s_security; 1182 if (!(sbsec->flags & SE_SBINITIALIZED)) { 1183 /* Defer initialization until selinux_complete_init, 1184 after the initial policy is loaded and the security 1185 server is ready to handle calls. */ 1186 spin_lock(&sbsec->isec_lock); 1187 if (list_empty(&isec->list)) 1188 list_add(&isec->list, &sbsec->isec_head); 1189 spin_unlock(&sbsec->isec_lock); 1190 goto out_unlock; 1191 } 1192 1193 switch (sbsec->behavior) { 1194 case SECURITY_FS_USE_XATTR: 1195 if (!inode->i_op->getxattr) { 1196 isec->sid = sbsec->def_sid; 1197 break; 1198 } 1199 1200 /* Need a dentry, since the xattr API requires one. 1201 Life would be simpler if we could just pass the inode. */ 1202 if (opt_dentry) { 1203 /* Called from d_instantiate or d_splice_alias. */ 1204 dentry = dget(opt_dentry); 1205 } else { 1206 /* Called from selinux_complete_init, try to find a dentry. */ 1207 dentry = d_find_alias(inode); 1208 } 1209 if (!dentry) { 1210 /* 1211 * this is can be hit on boot when a file is accessed 1212 * before the policy is loaded. When we load policy we 1213 * may find inodes that have no dentry on the 1214 * sbsec->isec_head list. No reason to complain as these 1215 * will get fixed up the next time we go through 1216 * inode_doinit with a dentry, before these inodes could 1217 * be used again by userspace. 1218 */ 1219 goto out_unlock; 1220 } 1221 1222 len = INITCONTEXTLEN; 1223 context = kmalloc(len+1, GFP_NOFS); 1224 if (!context) { 1225 rc = -ENOMEM; 1226 dput(dentry); 1227 goto out_unlock; 1228 } 1229 context[len] = '\0'; 1230 rc = inode->i_op->getxattr(dentry, XATTR_NAME_SELINUX, 1231 context, len); 1232 if (rc == -ERANGE) { 1233 kfree(context); 1234 1235 /* Need a larger buffer. Query for the right size. */ 1236 rc = inode->i_op->getxattr(dentry, XATTR_NAME_SELINUX, 1237 NULL, 0); 1238 if (rc < 0) { 1239 dput(dentry); 1240 goto out_unlock; 1241 } 1242 len = rc; 1243 context = kmalloc(len+1, GFP_NOFS); 1244 if (!context) { 1245 rc = -ENOMEM; 1246 dput(dentry); 1247 goto out_unlock; 1248 } 1249 context[len] = '\0'; 1250 rc = inode->i_op->getxattr(dentry, 1251 XATTR_NAME_SELINUX, 1252 context, len); 1253 } 1254 dput(dentry); 1255 if (rc < 0) { 1256 if (rc != -ENODATA) { 1257 printk(KERN_WARNING "SELinux: %s: getxattr returned " 1258 "%d for dev=%s ino=%ld\n", __func__, 1259 -rc, inode->i_sb->s_id, inode->i_ino); 1260 kfree(context); 1261 goto out_unlock; 1262 } 1263 /* Map ENODATA to the default file SID */ 1264 sid = sbsec->def_sid; 1265 rc = 0; 1266 } else { 1267 rc = security_context_to_sid_default(context, rc, &sid, 1268 sbsec->def_sid, 1269 GFP_NOFS); 1270 if (rc) { 1271 char *dev = inode->i_sb->s_id; 1272 unsigned long ino = inode->i_ino; 1273 1274 if (rc == -EINVAL) { 1275 if (printk_ratelimit()) 1276 printk(KERN_NOTICE "SELinux: inode=%lu on dev=%s was found to have an invalid " 1277 "context=%s. This indicates you may need to relabel the inode or the " 1278 "filesystem in question.\n", ino, dev, context); 1279 } else { 1280 printk(KERN_WARNING "SELinux: %s: context_to_sid(%s) " 1281 "returned %d for dev=%s ino=%ld\n", 1282 __func__, context, -rc, dev, ino); 1283 } 1284 kfree(context); 1285 /* Leave with the unlabeled SID */ 1286 rc = 0; 1287 break; 1288 } 1289 } 1290 kfree(context); 1291 isec->sid = sid; 1292 break; 1293 case SECURITY_FS_USE_TASK: 1294 isec->sid = isec->task_sid; 1295 break; 1296 case SECURITY_FS_USE_TRANS: 1297 /* Default to the fs SID. */ 1298 isec->sid = sbsec->sid; 1299 1300 /* Try to obtain a transition SID. */ 1301 isec->sclass = inode_mode_to_security_class(inode->i_mode); 1302 rc = security_transition_sid(isec->task_sid, sbsec->sid, 1303 isec->sclass, NULL, &sid); 1304 if (rc) 1305 goto out_unlock; 1306 isec->sid = sid; 1307 break; 1308 case SECURITY_FS_USE_MNTPOINT: 1309 isec->sid = sbsec->mntpoint_sid; 1310 break; 1311 default: 1312 /* Default to the fs superblock SID. */ 1313 isec->sid = sbsec->sid; 1314 1315 if ((sbsec->flags & SE_SBPROC) && !S_ISLNK(inode->i_mode)) { 1316 if (opt_dentry) { 1317 isec->sclass = inode_mode_to_security_class(inode->i_mode); 1318 rc = selinux_proc_get_sid(opt_dentry, 1319 isec->sclass, 1320 &sid); 1321 if (rc) 1322 goto out_unlock; 1323 isec->sid = sid; 1324 } 1325 } 1326 break; 1327 } 1328 1329 isec->initialized = 1; 1330 1331out_unlock: 1332 mutex_unlock(&isec->lock); 1333out: 1334 if (isec->sclass == SECCLASS_FILE) 1335 isec->sclass = inode_mode_to_security_class(inode->i_mode); 1336 return rc; 1337} 1338 1339/* Convert a Linux signal to an access vector. */ 1340static inline u32 signal_to_av(int sig) 1341{ 1342 u32 perm = 0; 1343 1344 switch (sig) { 1345 case SIGCHLD: 1346 /* Commonly granted from child to parent. */ 1347 perm = PROCESS__SIGCHLD; 1348 break; 1349 case SIGKILL: 1350 /* Cannot be caught or ignored */ 1351 perm = PROCESS__SIGKILL; 1352 break; 1353 case SIGSTOP: 1354 /* Cannot be caught or ignored */ 1355 perm = PROCESS__SIGSTOP; 1356 break; 1357 default: 1358 /* All other signals. */ 1359 perm = PROCESS__SIGNAL; 1360 break; 1361 } 1362 1363 return perm; 1364} 1365 1366/* 1367 * Check permission between a pair of credentials 1368 * fork check, ptrace check, etc. 1369 */ 1370static int cred_has_perm(const struct cred *actor, 1371 const struct cred *target, 1372 u32 perms) 1373{ 1374 u32 asid = cred_sid(actor), tsid = cred_sid(target); 1375 1376 return avc_has_perm(asid, tsid, SECCLASS_PROCESS, perms, NULL); 1377} 1378 1379/* 1380 * Check permission between a pair of tasks, e.g. signal checks, 1381 * fork check, ptrace check, etc. 1382 * tsk1 is the actor and tsk2 is the target 1383 * - this uses the default subjective creds of tsk1 1384 */ 1385static int task_has_perm(const struct task_struct *tsk1, 1386 const struct task_struct *tsk2, 1387 u32 perms) 1388{ 1389 const struct task_security_struct *__tsec1, *__tsec2; 1390 u32 sid1, sid2; 1391 1392 rcu_read_lock(); 1393 __tsec1 = __task_cred(tsk1)->security; sid1 = __tsec1->sid; 1394 __tsec2 = __task_cred(tsk2)->security; sid2 = __tsec2->sid; 1395 rcu_read_unlock(); 1396 return avc_has_perm(sid1, sid2, SECCLASS_PROCESS, perms, NULL); 1397} 1398 1399/* 1400 * Check permission between current and another task, e.g. signal checks, 1401 * fork check, ptrace check, etc. 1402 * current is the actor and tsk2 is the target 1403 * - this uses current's subjective creds 1404 */ 1405static int current_has_perm(const struct task_struct *tsk, 1406 u32 perms) 1407{ 1408 u32 sid, tsid; 1409 1410 sid = current_sid(); 1411 tsid = task_sid(tsk); 1412 return avc_has_perm(sid, tsid, SECCLASS_PROCESS, perms, NULL); 1413} 1414 1415#if CAP_LAST_CAP > 63 1416#error Fix SELinux to handle capabilities > 63. 1417#endif 1418 1419/* Check whether a task is allowed to use a capability. */ 1420static int task_has_capability(struct task_struct *tsk, 1421 const struct cred *cred, 1422 int cap, int audit) 1423{ 1424 struct common_audit_data ad; 1425 struct av_decision avd; 1426 u16 sclass; 1427 u32 sid = cred_sid(cred); 1428 u32 av = CAP_TO_MASK(cap); 1429 int rc; 1430 1431 COMMON_AUDIT_DATA_INIT(&ad, CAP); 1432 ad.tsk = tsk; 1433 ad.u.cap = cap; 1434 1435 switch (CAP_TO_INDEX(cap)) { 1436 case 0: 1437 sclass = SECCLASS_CAPABILITY; 1438 break; 1439 case 1: 1440 sclass = SECCLASS_CAPABILITY2; 1441 break; 1442 default: 1443 printk(KERN_ERR 1444 "SELinux: out of range capability %d\n", cap); 1445 BUG(); 1446 } 1447 1448 rc = avc_has_perm_noaudit(sid, sid, sclass, av, 0, &avd); 1449 if (audit == SECURITY_CAP_AUDIT) { 1450 int rc2 = avc_audit(sid, sid, sclass, av, &avd, rc, &ad, 0); 1451 if (rc2) 1452 return rc2; 1453 } 1454 return rc; 1455} 1456 1457/* Check whether a task is allowed to use a system operation. */ 1458static int task_has_system(struct task_struct *tsk, 1459 u32 perms) 1460{ 1461 u32 sid = task_sid(tsk); 1462 1463 return avc_has_perm(sid, SECINITSID_KERNEL, 1464 SECCLASS_SYSTEM, perms, NULL); 1465} 1466 1467/* Check whether a task has a particular permission to an inode. 1468 The 'adp' parameter is optional and allows other audit 1469 data to be passed (e.g. the dentry). */ 1470static int inode_has_perm(const struct cred *cred, 1471 struct inode *inode, 1472 u32 perms, 1473 struct common_audit_data *adp, 1474 unsigned flags) 1475{ 1476 struct inode_security_struct *isec; 1477 struct common_audit_data ad; 1478 u32 sid; 1479 1480 validate_creds(cred); 1481 1482 if (unlikely(IS_PRIVATE(inode))) 1483 return 0; 1484 1485 sid = cred_sid(cred); 1486 isec = inode->i_security; 1487 1488 if (!adp) { 1489 adp = &ad; 1490 COMMON_AUDIT_DATA_INIT(&ad, FS); 1491 ad.u.fs.inode = inode; 1492 } 1493 1494 return avc_has_perm_flags(sid, isec->sid, isec->sclass, perms, adp, flags); 1495} 1496 1497/* Same as inode_has_perm, but pass explicit audit data containing 1498 the dentry to help the auditing code to more easily generate the 1499 pathname if needed. */ 1500static inline int dentry_has_perm(const struct cred *cred, 1501 struct vfsmount *mnt, 1502 struct dentry *dentry, 1503 u32 av) 1504{ 1505 struct inode *inode = dentry->d_inode; 1506 struct common_audit_data ad; 1507 1508 COMMON_AUDIT_DATA_INIT(&ad, FS); 1509 ad.u.fs.path.mnt = mnt; 1510 ad.u.fs.path.dentry = dentry; 1511 return inode_has_perm(cred, inode, av, &ad, 0); 1512} 1513 1514/* Check whether a task can use an open file descriptor to 1515 access an inode in a given way. Check access to the 1516 descriptor itself, and then use dentry_has_perm to 1517 check a particular permission to the file. 1518 Access to the descriptor is implicitly granted if it 1519 has the same SID as the process. If av is zero, then 1520 access to the file is not checked, e.g. for cases 1521 where only the descriptor is affected like seek. */ 1522static int file_has_perm(const struct cred *cred, 1523 struct file *file, 1524 u32 av) 1525{ 1526 struct file_security_struct *fsec = file->f_security; 1527 struct inode *inode = file->f_path.dentry->d_inode; 1528 struct common_audit_data ad; 1529 u32 sid = cred_sid(cred); 1530 int rc; 1531 1532 COMMON_AUDIT_DATA_INIT(&ad, FS); 1533 ad.u.fs.path = file->f_path; 1534 1535 if (sid != fsec->sid) { 1536 rc = avc_has_perm(sid, fsec->sid, 1537 SECCLASS_FD, 1538 FD__USE, 1539 &ad); 1540 if (rc) 1541 goto out; 1542 } 1543 1544 /* av is zero if only checking access to the descriptor. */ 1545 rc = 0; 1546 if (av) 1547 rc = inode_has_perm(cred, inode, av, &ad, 0); 1548 1549out: 1550 return rc; 1551} 1552 1553/* Check whether a task can create a file. */ 1554static int may_create(struct inode *dir, 1555 struct dentry *dentry, 1556 u16 tclass) 1557{ 1558 const struct task_security_struct *tsec = current_security(); 1559 struct inode_security_struct *dsec; 1560 struct superblock_security_struct *sbsec; 1561 u32 sid, newsid; 1562 struct common_audit_data ad; 1563 int rc; 1564 1565 dsec = dir->i_security; 1566 sbsec = dir->i_sb->s_security; 1567 1568 sid = tsec->sid; 1569 newsid = tsec->create_sid; 1570 1571 COMMON_AUDIT_DATA_INIT(&ad, FS); 1572 ad.u.fs.path.dentry = dentry; 1573 1574 rc = avc_has_perm(sid, dsec->sid, SECCLASS_DIR, 1575 DIR__ADD_NAME | DIR__SEARCH, 1576 &ad); 1577 if (rc) 1578 return rc; 1579 1580 if (!newsid || !(sbsec->flags & SE_SBLABELSUPP)) { 1581 rc = security_transition_sid(sid, dsec->sid, tclass, 1582 &dentry->d_name, &newsid); 1583 if (rc) 1584 return rc; 1585 } 1586 1587 rc = avc_has_perm(sid, newsid, tclass, FILE__CREATE, &ad); 1588 if (rc) 1589 return rc; 1590 1591 return avc_has_perm(newsid, sbsec->sid, 1592 SECCLASS_FILESYSTEM, 1593 FILESYSTEM__ASSOCIATE, &ad); 1594} 1595 1596/* Check whether a task can create a key. */ 1597static int may_create_key(u32 ksid, 1598 struct task_struct *ctx) 1599{ 1600 u32 sid = task_sid(ctx); 1601 1602 return avc_has_perm(sid, ksid, SECCLASS_KEY, KEY__CREATE, NULL); 1603} 1604 1605#define MAY_LINK 0 1606#define MAY_UNLINK 1 1607#define MAY_RMDIR 2 1608 1609/* Check whether a task can link, unlink, or rmdir a file/directory. */ 1610static int may_link(struct inode *dir, 1611 struct dentry *dentry, 1612 int kind) 1613 1614{ 1615 struct inode_security_struct *dsec, *isec; 1616 struct common_audit_data ad; 1617 u32 sid = current_sid(); 1618 u32 av; 1619 int rc; 1620 1621 dsec = dir->i_security; 1622 isec = dentry->d_inode->i_security; 1623 1624 COMMON_AUDIT_DATA_INIT(&ad, FS); 1625 ad.u.fs.path.dentry = dentry; 1626 1627 av = DIR__SEARCH; 1628 av |= (kind ? DIR__REMOVE_NAME : DIR__ADD_NAME); 1629 rc = avc_has_perm(sid, dsec->sid, SECCLASS_DIR, av, &ad); 1630 if (rc) 1631 return rc; 1632 1633 switch (kind) { 1634 case MAY_LINK: 1635 av = FILE__LINK; 1636 break; 1637 case MAY_UNLINK: 1638 av = FILE__UNLINK; 1639 break; 1640 case MAY_RMDIR: 1641 av = DIR__RMDIR; 1642 break; 1643 default: 1644 printk(KERN_WARNING "SELinux: %s: unrecognized kind %d\n", 1645 __func__, kind); 1646 return 0; 1647 } 1648 1649 rc = avc_has_perm(sid, isec->sid, isec->sclass, av, &ad); 1650 return rc; 1651} 1652 1653static inline int may_rename(struct inode *old_dir, 1654 struct dentry *old_dentry, 1655 struct inode *new_dir, 1656 struct dentry *new_dentry) 1657{ 1658 struct inode_security_struct *old_dsec, *new_dsec, *old_isec, *new_isec; 1659 struct common_audit_data ad; 1660 u32 sid = current_sid(); 1661 u32 av; 1662 int old_is_dir, new_is_dir; 1663 int rc; 1664 1665 old_dsec = old_dir->i_security; 1666 old_isec = old_dentry->d_inode->i_security; 1667 old_is_dir = S_ISDIR(old_dentry->d_inode->i_mode); 1668 new_dsec = new_dir->i_security; 1669 1670 COMMON_AUDIT_DATA_INIT(&ad, FS); 1671 1672 ad.u.fs.path.dentry = old_dentry; 1673 rc = avc_has_perm(sid, old_dsec->sid, SECCLASS_DIR, 1674 DIR__REMOVE_NAME | DIR__SEARCH, &ad); 1675 if (rc) 1676 return rc; 1677 rc = avc_has_perm(sid, old_isec->sid, 1678 old_isec->sclass, FILE__RENAME, &ad); 1679 if (rc) 1680 return rc; 1681 if (old_is_dir && new_dir != old_dir) { 1682 rc = avc_has_perm(sid, old_isec->sid, 1683 old_isec->sclass, DIR__REPARENT, &ad); 1684 if (rc) 1685 return rc; 1686 } 1687 1688 ad.u.fs.path.dentry = new_dentry; 1689 av = DIR__ADD_NAME | DIR__SEARCH; 1690 if (new_dentry->d_inode) 1691 av |= DIR__REMOVE_NAME; 1692 rc = avc_has_perm(sid, new_dsec->sid, SECCLASS_DIR, av, &ad); 1693 if (rc) 1694 return rc; 1695 if (new_dentry->d_inode) { 1696 new_isec = new_dentry->d_inode->i_security; 1697 new_is_dir = S_ISDIR(new_dentry->d_inode->i_mode); 1698 rc = avc_has_perm(sid, new_isec->sid, 1699 new_isec->sclass, 1700 (new_is_dir ? DIR__RMDIR : FILE__UNLINK), &ad); 1701 if (rc) 1702 return rc; 1703 } 1704 1705 return 0; 1706} 1707 1708/* Check whether a task can perform a filesystem operation. */ 1709static int superblock_has_perm(const struct cred *cred, 1710 struct super_block *sb, 1711 u32 perms, 1712 struct common_audit_data *ad) 1713{ 1714 struct superblock_security_struct *sbsec; 1715 u32 sid = cred_sid(cred); 1716 1717 sbsec = sb->s_security; 1718 return avc_has_perm(sid, sbsec->sid, SECCLASS_FILESYSTEM, perms, ad); 1719} 1720 1721/* Convert a Linux mode and permission mask to an access vector. */ 1722static inline u32 file_mask_to_av(int mode, int mask) 1723{ 1724 u32 av = 0; 1725 1726 if ((mode & S_IFMT) != S_IFDIR) { 1727 if (mask & MAY_EXEC) 1728 av |= FILE__EXECUTE; 1729 if (mask & MAY_READ) 1730 av |= FILE__READ; 1731 1732 if (mask & MAY_APPEND) 1733 av |= FILE__APPEND; 1734 else if (mask & MAY_WRITE) 1735 av |= FILE__WRITE; 1736 1737 } else { 1738 if (mask & MAY_EXEC) 1739 av |= DIR__SEARCH; 1740 if (mask & MAY_WRITE) 1741 av |= DIR__WRITE; 1742 if (mask & MAY_READ) 1743 av |= DIR__READ; 1744 } 1745 1746 return av; 1747} 1748 1749/* Convert a Linux file to an access vector. */ 1750static inline u32 file_to_av(struct file *file) 1751{ 1752 u32 av = 0; 1753 1754 if (file->f_mode & FMODE_READ) 1755 av |= FILE__READ; 1756 if (file->f_mode & FMODE_WRITE) { 1757 if (file->f_flags & O_APPEND) 1758 av |= FILE__APPEND; 1759 else 1760 av |= FILE__WRITE; 1761 } 1762 if (!av) { 1763 /* 1764 * Special file opened with flags 3 for ioctl-only use. 1765 */ 1766 av = FILE__IOCTL; 1767 } 1768 1769 return av; 1770} 1771 1772/* 1773 * Convert a file to an access vector and include the correct open 1774 * open permission. 1775 */ 1776static inline u32 open_file_to_av(struct file *file) 1777{ 1778 u32 av = file_to_av(file); 1779 1780 if (selinux_policycap_openperm) 1781 av |= FILE__OPEN; 1782 1783 return av; 1784} 1785 1786/* Hook functions begin here. */ 1787 1788static int selinux_ptrace_access_check(struct task_struct *child, 1789 unsigned int mode) 1790{ 1791 int rc; 1792 1793 rc = cap_ptrace_access_check(child, mode); 1794 if (rc) 1795 return rc; 1796 1797 if (mode == PTRACE_MODE_READ) { 1798 u32 sid = current_sid(); 1799 u32 csid = task_sid(child); 1800 return avc_has_perm(sid, csid, SECCLASS_FILE, FILE__READ, NULL); 1801 } 1802 1803 return current_has_perm(child, PROCESS__PTRACE); 1804} 1805 1806static int selinux_ptrace_traceme(struct task_struct *parent) 1807{ 1808 int rc; 1809 1810 rc = cap_ptrace_traceme(parent); 1811 if (rc) 1812 return rc; 1813 1814 return task_has_perm(parent, current, PROCESS__PTRACE); 1815} 1816 1817static int selinux_capget(struct task_struct *target, kernel_cap_t *effective, 1818 kernel_cap_t *inheritable, kernel_cap_t *permitted) 1819{ 1820 int error; 1821 1822 error = current_has_perm(target, PROCESS__GETCAP); 1823 if (error) 1824 return error; 1825 1826 return cap_capget(target, effective, inheritable, permitted); 1827} 1828 1829static int selinux_capset(struct cred *new, const struct cred *old, 1830 const kernel_cap_t *effective, 1831 const kernel_cap_t *inheritable, 1832 const kernel_cap_t *permitted) 1833{ 1834 int error; 1835 1836 error = cap_capset(new, old, 1837 effective, inheritable, permitted); 1838 if (error) 1839 return error; 1840 1841 return cred_has_perm(old, new, PROCESS__SETCAP); 1842} 1843 1844/* 1845 * (This comment used to live with the selinux_task_setuid hook, 1846 * which was removed). 1847 * 1848 * Since setuid only affects the current process, and since the SELinux 1849 * controls are not based on the Linux identity attributes, SELinux does not 1850 * need to control this operation. However, SELinux does control the use of 1851 * the CAP_SETUID and CAP_SETGID capabilities using the capable hook. 1852 */ 1853 1854static int selinux_capable(struct task_struct *tsk, const struct cred *cred, 1855 struct user_namespace *ns, int cap, int audit) 1856{ 1857 int rc; 1858 1859 rc = cap_capable(tsk, cred, ns, cap, audit); 1860 if (rc) 1861 return rc; 1862 1863 return task_has_capability(tsk, cred, cap, audit); 1864} 1865 1866static int selinux_quotactl(int cmds, int type, int id, struct super_block *sb) 1867{ 1868 const struct cred *cred = current_cred(); 1869 int rc = 0; 1870 1871 if (!sb) 1872 return 0; 1873 1874 switch (cmds) { 1875 case Q_SYNC: 1876 case Q_QUOTAON: 1877 case Q_QUOTAOFF: 1878 case Q_SETINFO: 1879 case Q_SETQUOTA: 1880 rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAMOD, NULL); 1881 break; 1882 case Q_GETFMT: 1883 case Q_GETINFO: 1884 case Q_GETQUOTA: 1885 rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAGET, NULL); 1886 break; 1887 default: 1888 rc = 0; /* let the kernel handle invalid cmds */ 1889 break; 1890 } 1891 return rc; 1892} 1893 1894static int selinux_quota_on(struct dentry *dentry) 1895{ 1896 const struct cred *cred = current_cred(); 1897 1898 return dentry_has_perm(cred, NULL, dentry, FILE__QUOTAON); 1899} 1900 1901static int selinux_syslog(int type) 1902{ 1903 int rc; 1904 1905 switch (type) { 1906 case SYSLOG_ACTION_READ_ALL: /* Read last kernel messages */ 1907 case SYSLOG_ACTION_SIZE_BUFFER: /* Return size of the log buffer */ 1908 rc = task_has_system(current, SYSTEM__SYSLOG_READ); 1909 break; 1910 case SYSLOG_ACTION_CONSOLE_OFF: /* Disable logging to console */ 1911 case SYSLOG_ACTION_CONSOLE_ON: /* Enable logging to console */ 1912 /* Set level of messages printed to console */ 1913 case SYSLOG_ACTION_CONSOLE_LEVEL: 1914 rc = task_has_system(current, SYSTEM__SYSLOG_CONSOLE); 1915 break; 1916 case SYSLOG_ACTION_CLOSE: /* Close log */ 1917 case SYSLOG_ACTION_OPEN: /* Open log */ 1918 case SYSLOG_ACTION_READ: /* Read from log */ 1919 case SYSLOG_ACTION_READ_CLEAR: /* Read/clear last kernel messages */ 1920 case SYSLOG_ACTION_CLEAR: /* Clear ring buffer */ 1921 default: 1922 rc = task_has_system(current, SYSTEM__SYSLOG_MOD); 1923 break; 1924 } 1925 return rc; 1926} 1927 1928/* 1929 * Check that a process has enough memory to allocate a new virtual 1930 * mapping. 0 means there is enough memory for the allocation to 1931 * succeed and -ENOMEM implies there is not. 1932 * 1933 * Do not audit the selinux permission check, as this is applied to all 1934 * processes that allocate mappings. 1935 */ 1936static int selinux_vm_enough_memory(struct mm_struct *mm, long pages) 1937{ 1938 int rc, cap_sys_admin = 0; 1939 1940 rc = selinux_capable(current, current_cred(), 1941 &init_user_ns, CAP_SYS_ADMIN, 1942 SECURITY_CAP_NOAUDIT); 1943 if (rc == 0) 1944 cap_sys_admin = 1; 1945 1946 return __vm_enough_memory(mm, pages, cap_sys_admin); 1947} 1948 1949/* binprm security operations */ 1950 1951static int selinux_bprm_set_creds(struct linux_binprm *bprm) 1952{ 1953 const struct task_security_struct *old_tsec; 1954 struct task_security_struct *new_tsec; 1955 struct inode_security_struct *isec; 1956 struct common_audit_data ad; 1957 struct inode *inode = bprm->file->f_path.dentry->d_inode; 1958 int rc; 1959 1960 rc = cap_bprm_set_creds(bprm); 1961 if (rc) 1962 return rc; 1963 1964 /* SELinux context only depends on initial program or script and not 1965 * the script interpreter */ 1966 if (bprm->cred_prepared) 1967 return 0; 1968 1969 old_tsec = current_security(); 1970 new_tsec = bprm->cred->security; 1971 isec = inode->i_security; 1972 1973 /* Default to the current task SID. */ 1974 new_tsec->sid = old_tsec->sid; 1975 new_tsec->osid = old_tsec->sid; 1976 1977 /* Reset fs, key, and sock SIDs on execve. */ 1978 new_tsec->create_sid = 0; 1979 new_tsec->keycreate_sid = 0; 1980 new_tsec->sockcreate_sid = 0; 1981 1982 if (old_tsec->exec_sid) { 1983 new_tsec->sid = old_tsec->exec_sid; 1984 /* Reset exec SID on execve. */ 1985 new_tsec->exec_sid = 0; 1986 } else { 1987 /* Check for a default transition on this program. */ 1988 rc = security_transition_sid(old_tsec->sid, isec->sid, 1989 SECCLASS_PROCESS, NULL, 1990 &new_tsec->sid); 1991 if (rc) 1992 return rc; 1993 } 1994 1995 COMMON_AUDIT_DATA_INIT(&ad, FS); 1996 ad.u.fs.path = bprm->file->f_path; 1997 1998 if (bprm->file->f_path.mnt->mnt_flags & MNT_NOSUID) 1999 new_tsec->sid = old_tsec->sid; 2000 2001 if (new_tsec->sid == old_tsec->sid) { 2002 rc = avc_has_perm(old_tsec->sid, isec->sid, 2003 SECCLASS_FILE, FILE__EXECUTE_NO_TRANS, &ad); 2004 if (rc) 2005 return rc; 2006 } else { 2007 /* Check permissions for the transition. */ 2008 rc = avc_has_perm(old_tsec->sid, new_tsec->sid, 2009 SECCLASS_PROCESS, PROCESS__TRANSITION, &ad); 2010 if (rc) 2011 return rc; 2012 2013 rc = avc_has_perm(new_tsec->sid, isec->sid, 2014 SECCLASS_FILE, FILE__ENTRYPOINT, &ad); 2015 if (rc) 2016 return rc; 2017 2018 /* Check for shared state */ 2019 if (bprm->unsafe & LSM_UNSAFE_SHARE) { 2020 rc = avc_has_perm(old_tsec->sid, new_tsec->sid, 2021 SECCLASS_PROCESS, PROCESS__SHARE, 2022 NULL); 2023 if (rc) 2024 return -EPERM; 2025 } 2026 2027 /* Make sure that anyone attempting to ptrace over a task that 2028 * changes its SID has the appropriate permit */ 2029 if (bprm->unsafe & 2030 (LSM_UNSAFE_PTRACE | LSM_UNSAFE_PTRACE_CAP)) { 2031 struct task_struct *tracer; 2032 struct task_security_struct *sec; 2033 u32 ptsid = 0; 2034 2035 rcu_read_lock(); 2036 tracer = tracehook_tracer_task(current); 2037 if (likely(tracer != NULL)) { 2038 sec = __task_cred(tracer)->security; 2039 ptsid = sec->sid; 2040 } 2041 rcu_read_unlock(); 2042 2043 if (ptsid != 0) { 2044 rc = avc_has_perm(ptsid, new_tsec->sid, 2045 SECCLASS_PROCESS, 2046 PROCESS__PTRACE, NULL); 2047 if (rc) 2048 return -EPERM; 2049 } 2050 } 2051 2052 /* Clear any possibly unsafe personality bits on exec: */ 2053 bprm->per_clear |= PER_CLEAR_ON_SETID; 2054 } 2055 2056 return 0; 2057} 2058 2059static int selinux_bprm_secureexec(struct linux_binprm *bprm) 2060{ 2061 const struct task_security_struct *tsec = current_security(); 2062 u32 sid, osid; 2063 int atsecure = 0; 2064 2065 sid = tsec->sid; 2066 osid = tsec->osid; 2067 2068 if (osid != sid) { 2069 /* Enable secure mode for SIDs transitions unless 2070 the noatsecure permission is granted between 2071 the two SIDs, i.e. ahp returns 0. */ 2072 atsecure = avc_has_perm(osid, sid, 2073 SECCLASS_PROCESS, 2074 PROCESS__NOATSECURE, NULL); 2075 } 2076 2077 return (atsecure || cap_bprm_secureexec(bprm)); 2078} 2079 2080extern struct vfsmount *selinuxfs_mount; 2081extern struct dentry *selinux_null; 2082 2083/* Derived from fs/exec.c:flush_old_files. */ 2084static inline void flush_unauthorized_files(const struct cred *cred, 2085 struct files_struct *files) 2086{ 2087 struct common_audit_data ad; 2088 struct file *file, *devnull = NULL; 2089 struct tty_struct *tty; 2090 struct fdtable *fdt; 2091 long j = -1; 2092 int drop_tty = 0; 2093 2094 tty = get_current_tty(); 2095 if (tty) { 2096 spin_lock(&tty_files_lock); 2097 if (!list_empty(&tty->tty_files)) { 2098 struct tty_file_private *file_priv; 2099 struct inode *inode; 2100 2101 /* Revalidate access to controlling tty. 2102 Use inode_has_perm on the tty inode directly rather 2103 than using file_has_perm, as this particular open 2104 file may belong to another process and we are only 2105 interested in the inode-based check here. */ 2106 file_priv = list_first_entry(&tty->tty_files, 2107 struct tty_file_private, list); 2108 file = file_priv->file; 2109 inode = file->f_path.dentry->d_inode; 2110 if (inode_has_perm(cred, inode, 2111 FILE__READ | FILE__WRITE, NULL, 0)) { 2112 drop_tty = 1; 2113 } 2114 } 2115 spin_unlock(&tty_files_lock); 2116 tty_kref_put(tty); 2117 } 2118 /* Reset controlling tty. */ 2119 if (drop_tty) 2120 no_tty(); 2121 2122 /* Revalidate access to inherited open files. */ 2123 2124 COMMON_AUDIT_DATA_INIT(&ad, FS); 2125 2126 spin_lock(&files->file_lock); 2127 for (;;) { 2128 unsigned long set, i; 2129 int fd; 2130 2131 j++; 2132 i = j * __NFDBITS; 2133 fdt = files_fdtable(files); 2134 if (i >= fdt->max_fds) 2135 break; 2136 set = fdt->open_fds->fds_bits[j]; 2137 if (!set) 2138 continue; 2139 spin_unlock(&files->file_lock); 2140 for ( ; set ; i++, set >>= 1) { 2141 if (set & 1) { 2142 file = fget(i); 2143 if (!file) 2144 continue; 2145 if (file_has_perm(cred, 2146 file, 2147 file_to_av(file))) { 2148 sys_close(i); 2149 fd = get_unused_fd(); 2150 if (fd != i) { 2151 if (fd >= 0) 2152 put_unused_fd(fd); 2153 fput(file); 2154 continue; 2155 } 2156 if (devnull) { 2157 get_file(devnull); 2158 } else { 2159 devnull = dentry_open( 2160 dget(selinux_null), 2161 mntget(selinuxfs_mount), 2162 O_RDWR, cred); 2163 if (IS_ERR(devnull)) { 2164 devnull = NULL; 2165 put_unused_fd(fd); 2166 fput(file); 2167 continue; 2168 } 2169 } 2170 fd_install(fd, devnull); 2171 } 2172 fput(file); 2173 } 2174 } 2175 spin_lock(&files->file_lock); 2176 2177 } 2178 spin_unlock(&files->file_lock); 2179} 2180 2181/* 2182 * Prepare a process for imminent new credential changes due to exec 2183 */ 2184static void selinux_bprm_committing_creds(struct linux_binprm *bprm) 2185{ 2186 struct task_security_struct *new_tsec; 2187 struct rlimit *rlim, *initrlim; 2188 int rc, i; 2189 2190 new_tsec = bprm->cred->security; 2191 if (new_tsec->sid == new_tsec->osid) 2192 return; 2193 2194 /* Close files for which the new task SID is not authorized. */ 2195 flush_unauthorized_files(bprm->cred, current->files); 2196 2197 /* Always clear parent death signal on SID transitions. */ 2198 current->pdeath_signal = 0; 2199 2200 /* Check whether the new SID can inherit resource limits from the old 2201 * SID. If not, reset all soft limits to the lower of the current 2202 * task's hard limit and the init task's soft limit. 2203 * 2204 * Note that the setting of hard limits (even to lower them) can be 2205 * controlled by the setrlimit check. The inclusion of the init task's 2206 * soft limit into the computation is to avoid resetting soft limits 2207 * higher than the default soft limit for cases where the default is 2208 * lower than the hard limit, e.g. RLIMIT_CORE or RLIMIT_STACK. 2209 */ 2210 rc = avc_has_perm(new_tsec->osid, new_tsec->sid, SECCLASS_PROCESS, 2211 PROCESS__RLIMITINH, NULL); 2212 if (rc) { 2213 /* protect against do_prlimit() */ 2214 task_lock(current); 2215 for (i = 0; i < RLIM_NLIMITS; i++) { 2216 rlim = current->signal->rlim + i; 2217 initrlim = init_task.signal->rlim + i; 2218 rlim->rlim_cur = min(rlim->rlim_max, initrlim->rlim_cur); 2219 } 2220 task_unlock(current); 2221 update_rlimit_cpu(current, rlimit(RLIMIT_CPU)); 2222 } 2223} 2224 2225/* 2226 * Clean up the process immediately after the installation of new credentials 2227 * due to exec 2228 */ 2229static void selinux_bprm_committed_creds(struct linux_binprm *bprm) 2230{ 2231 const struct task_security_struct *tsec = current_security(); 2232 struct itimerval itimer; 2233 u32 osid, sid; 2234 int rc, i; 2235 2236 osid = tsec->osid; 2237 sid = tsec->sid; 2238 2239 if (sid == osid) 2240 return; 2241 2242 /* Check whether the new SID can inherit signal state from the old SID. 2243 * If not, clear itimers to avoid subsequent signal generation and 2244 * flush and unblock signals. 2245 * 2246 * This must occur _after_ the task SID has been updated so that any 2247 * kill done after the flush will be checked against the new SID. 2248 */ 2249 rc = avc_has_perm(osid, sid, SECCLASS_PROCESS, PROCESS__SIGINH, NULL); 2250 if (rc) { 2251 memset(&itimer, 0, sizeof itimer); 2252 for (i = 0; i < 3; i++) 2253 do_setitimer(i, &itimer, NULL); 2254 spin_lock_irq(&current->sighand->siglock); 2255 if (!(current->signal->flags & SIGNAL_GROUP_EXIT)) { 2256 __flush_signals(current); 2257 flush_signal_handlers(current, 1); 2258 sigemptyset(&current->blocked); 2259 } 2260 spin_unlock_irq(&current->sighand->siglock); 2261 } 2262 2263 /* Wake up the parent if it is waiting so that it can recheck 2264 * wait permission to the new task SID. */ 2265 read_lock(&tasklist_lock); 2266 __wake_up_parent(current, current->real_parent); 2267 read_unlock(&tasklist_lock); 2268} 2269 2270/* superblock security operations */ 2271 2272static int selinux_sb_alloc_security(struct super_block *sb) 2273{ 2274 return superblock_alloc_security(sb); 2275} 2276 2277static void selinux_sb_free_security(struct super_block *sb) 2278{ 2279 superblock_free_security(sb); 2280} 2281 2282static inline int match_prefix(char *prefix, int plen, char *option, int olen) 2283{ 2284 if (plen > olen) 2285 return 0; 2286 2287 return !memcmp(prefix, option, plen); 2288} 2289 2290static inline int selinux_option(char *option, int len) 2291{ 2292 return (match_prefix(CONTEXT_STR, sizeof(CONTEXT_STR)-1, option, len) || 2293 match_prefix(FSCONTEXT_STR, sizeof(FSCONTEXT_STR)-1, option, len) || 2294 match_prefix(DEFCONTEXT_STR, sizeof(DEFCONTEXT_STR)-1, option, len) || 2295 match_prefix(ROOTCONTEXT_STR, sizeof(ROOTCONTEXT_STR)-1, option, len) || 2296 match_prefix(LABELSUPP_STR, sizeof(LABELSUPP_STR)-1, option, len)); 2297} 2298 2299static inline void take_option(char **to, char *from, int *first, int len) 2300{ 2301 if (!*first) { 2302 **to = ','; 2303 *to += 1; 2304 } else 2305 *first = 0; 2306 memcpy(*to, from, len); 2307 *to += len; 2308} 2309 2310static inline void take_selinux_option(char **to, char *from, int *first, 2311 int len) 2312{ 2313 int current_size = 0; 2314 2315 if (!*first) { 2316 **to = '|'; 2317 *to += 1; 2318 } else 2319 *first = 0; 2320 2321 while (current_size < len) { 2322 if (*from != '"') { 2323 **to = *from; 2324 *to += 1; 2325 } 2326 from += 1; 2327 current_size += 1; 2328 } 2329} 2330 2331static int selinux_sb_copy_data(char *orig, char *copy) 2332{ 2333 int fnosec, fsec, rc = 0; 2334 char *in_save, *in_curr, *in_end; 2335 char *sec_curr, *nosec_save, *nosec; 2336 int open_quote = 0; 2337 2338 in_curr = orig; 2339 sec_curr = copy; 2340 2341 nosec = (char *)get_zeroed_page(GFP_KERNEL); 2342 if (!nosec) { 2343 rc = -ENOMEM; 2344 goto out; 2345 } 2346 2347 nosec_save = nosec; 2348 fnosec = fsec = 1; 2349 in_save = in_end = orig; 2350 2351 do { 2352 if (*in_end == '"') 2353 open_quote = !open_quote; 2354 if ((*in_end == ',' && open_quote == 0) || 2355 *in_end == '\0') { 2356 int len = in_end - in_curr; 2357 2358 if (selinux_option(in_curr, len)) 2359 take_selinux_option(&sec_curr, in_curr, &fsec, len); 2360 else 2361 take_option(&nosec, in_curr, &fnosec, len); 2362 2363 in_curr = in_end + 1; 2364 } 2365 } while (*in_end++); 2366 2367 strcpy(in_save, nosec_save); 2368 free_page((unsigned long)nosec_save); 2369out: 2370 return rc; 2371} 2372 2373static int selinux_sb_remount(struct super_block *sb, void *data) 2374{ 2375 int rc, i, *flags; 2376 struct security_mnt_opts opts; 2377 char *secdata, **mount_options; 2378 struct superblock_security_struct *sbsec = sb->s_security; 2379 2380 if (!(sbsec->flags & SE_SBINITIALIZED)) 2381 return 0; 2382 2383 if (!data) 2384 return 0; 2385 2386 if (sb->s_type->fs_flags & FS_BINARY_MOUNTDATA) 2387 return 0; 2388 2389 security_init_mnt_opts(&opts); 2390 secdata = alloc_secdata(); 2391 if (!secdata) 2392 return -ENOMEM; 2393 rc = selinux_sb_copy_data(data, secdata); 2394 if (rc) 2395 goto out_free_secdata; 2396 2397 rc = selinux_parse_opts_str(secdata, &opts); 2398 if (rc) 2399 goto out_free_secdata; 2400 2401 mount_options = opts.mnt_opts; 2402 flags = opts.mnt_opts_flags; 2403 2404 for (i = 0; i < opts.num_mnt_opts; i++) { 2405 u32 sid; 2406 size_t len; 2407 2408 if (flags[i] == SE_SBLABELSUPP) 2409 continue; 2410 len = strlen(mount_options[i]); 2411 rc = security_context_to_sid(mount_options[i], len, &sid); 2412 if (rc) { 2413 printk(KERN_WARNING "SELinux: security_context_to_sid" 2414 "(%s) failed for (dev %s, type %s) errno=%d\n", 2415 mount_options[i], sb->s_id, sb->s_type->name, rc); 2416 goto out_free_opts; 2417 } 2418 rc = -EINVAL; 2419 switch (flags[i]) { 2420 case FSCONTEXT_MNT: 2421 if (bad_option(sbsec, FSCONTEXT_MNT, sbsec->sid, sid)) 2422 goto out_bad_option; 2423 break; 2424 case CONTEXT_MNT: 2425 if (bad_option(sbsec, CONTEXT_MNT, sbsec->mntpoint_sid, sid)) 2426 goto out_bad_option; 2427 break; 2428 case ROOTCONTEXT_MNT: { 2429 struct inode_security_struct *root_isec; 2430 root_isec = sb->s_root->d_inode->i_security; 2431 2432 if (bad_option(sbsec, ROOTCONTEXT_MNT, root_isec->sid, sid)) 2433 goto out_bad_option; 2434 break; 2435 } 2436 case DEFCONTEXT_MNT: 2437 if (bad_option(sbsec, DEFCONTEXT_MNT, sbsec->def_sid, sid)) 2438 goto out_bad_option; 2439 break; 2440 default: 2441 goto out_free_opts; 2442 } 2443 } 2444 2445 rc = 0; 2446out_free_opts: 2447 security_free_mnt_opts(&opts); 2448out_free_secdata: 2449 free_secdata(secdata); 2450 return rc; 2451out_bad_option: 2452 printk(KERN_WARNING "SELinux: unable to change security options " 2453 "during remount (dev %s, type=%s)\n", sb->s_id, 2454 sb->s_type->name); 2455 goto out_free_opts; 2456} 2457 2458static int selinux_sb_kern_mount(struct super_block *sb, int flags, void *data) 2459{ 2460 const struct cred *cred = current_cred(); 2461 struct common_audit_data ad; 2462 int rc; 2463 2464 rc = superblock_doinit(sb, data); 2465 if (rc) 2466 return rc; 2467 2468 /* Allow all mounts performed by the kernel */ 2469 if (flags & MS_KERNMOUNT) 2470 return 0; 2471 2472 COMMON_AUDIT_DATA_INIT(&ad, FS); 2473 ad.u.fs.path.dentry = sb->s_root; 2474 return superblock_has_perm(cred, sb, FILESYSTEM__MOUNT, &ad); 2475} 2476 2477static int selinux_sb_statfs(struct dentry *dentry) 2478{ 2479 const struct cred *cred = current_cred(); 2480 struct common_audit_data ad; 2481 2482 COMMON_AUDIT_DATA_INIT(&ad, FS); 2483 ad.u.fs.path.dentry = dentry->d_sb->s_root; 2484 return superblock_has_perm(cred, dentry->d_sb, FILESYSTEM__GETATTR, &ad); 2485} 2486 2487static int selinux_mount(char *dev_name, 2488 struct path *path, 2489 char *type, 2490 unsigned long flags, 2491 void *data) 2492{ 2493 const struct cred *cred = current_cred(); 2494 2495 if (flags & MS_REMOUNT) 2496 return superblock_has_perm(cred, path->mnt->mnt_sb, 2497 FILESYSTEM__REMOUNT, NULL); 2498 else 2499 return dentry_has_perm(cred, path->mnt, path->dentry, 2500 FILE__MOUNTON); 2501} 2502 2503static int selinux_umount(struct vfsmount *mnt, int flags) 2504{ 2505 const struct cred *cred = current_cred(); 2506 2507 return superblock_has_perm(cred, mnt->mnt_sb, 2508 FILESYSTEM__UNMOUNT, NULL); 2509} 2510 2511/* inode security operations */ 2512 2513static int selinux_inode_alloc_security(struct inode *inode) 2514{ 2515 return inode_alloc_security(inode); 2516} 2517 2518static void selinux_inode_free_security(struct inode *inode) 2519{ 2520 inode_free_security(inode); 2521} 2522 2523static int selinux_inode_init_security(struct inode *inode, struct inode *dir, 2524 const struct qstr *qstr, char **name, 2525 void **value, size_t *len) 2526{ 2527 const struct task_security_struct *tsec = current_security(); 2528 struct inode_security_struct *dsec; 2529 struct superblock_security_struct *sbsec; 2530 u32 sid, newsid, clen; 2531 int rc; 2532 char *namep = NULL, *context; 2533 2534 dsec = dir->i_security; 2535 sbsec = dir->i_sb->s_security; 2536 2537 sid = tsec->sid; 2538 newsid = tsec->create_sid; 2539 2540 if ((sbsec->flags & SE_SBINITIALIZED) && 2541 (sbsec->behavior == SECURITY_FS_USE_MNTPOINT)) 2542 newsid = sbsec->mntpoint_sid; 2543 else if (!newsid || !(sbsec->flags & SE_SBLABELSUPP)) { 2544 rc = security_transition_sid(sid, dsec->sid, 2545 inode_mode_to_security_class(inode->i_mode), 2546 qstr, &newsid); 2547 if (rc) { 2548 printk(KERN_WARNING "%s: " 2549 "security_transition_sid failed, rc=%d (dev=%s " 2550 "ino=%ld)\n", 2551 __func__, 2552 -rc, inode->i_sb->s_id, inode->i_ino); 2553 return rc; 2554 } 2555 } 2556 2557 /* Possibly defer initialization to selinux_complete_init. */ 2558 if (sbsec->flags & SE_SBINITIALIZED) { 2559 struct inode_security_struct *isec = inode->i_security; 2560 isec->sclass = inode_mode_to_security_class(inode->i_mode); 2561 isec->sid = newsid; 2562 isec->initialized = 1; 2563 } 2564 2565 if (!ss_initialized || !(sbsec->flags & SE_SBLABELSUPP)) 2566 return -EOPNOTSUPP; 2567 2568 if (name) { 2569 namep = kstrdup(XATTR_SELINUX_SUFFIX, GFP_NOFS); 2570 if (!namep) 2571 return -ENOMEM; 2572 *name = namep; 2573 } 2574 2575 if (value && len) { 2576 rc = security_sid_to_context_force(newsid, &context, &clen); 2577 if (rc) { 2578 kfree(namep); 2579 return rc; 2580 } 2581 *value = context; 2582 *len = clen; 2583 } 2584 2585 return 0; 2586} 2587 2588static int selinux_inode_create(struct inode *dir, struct dentry *dentry, int mask) 2589{ 2590 return may_create(dir, dentry, SECCLASS_FILE); 2591} 2592 2593static int selinux_inode_link(struct dentry *old_dentry, struct inode *dir, struct dentry *new_dentry) 2594{ 2595 return may_link(dir, old_dentry, MAY_LINK); 2596} 2597 2598static int selinux_inode_unlink(struct inode *dir, struct dentry *dentry) 2599{ 2600 return may_link(dir, dentry, MAY_UNLINK); 2601} 2602 2603static int selinux_inode_symlink(struct inode *dir, struct dentry *dentry, const char *name) 2604{ 2605 return may_create(dir, dentry, SECCLASS_LNK_FILE); 2606} 2607 2608static int selinux_inode_mkdir(struct inode *dir, struct dentry *dentry, int mask) 2609{ 2610 return may_create(dir, dentry, SECCLASS_DIR); 2611} 2612 2613static int selinux_inode_rmdir(struct inode *dir, struct dentry *dentry) 2614{ 2615 return may_link(dir, dentry, MAY_RMDIR); 2616} 2617 2618static int selinux_inode_mknod(struct inode *dir, struct dentry *dentry, int mode, dev_t dev) 2619{ 2620 return may_create(dir, dentry, inode_mode_to_security_class(mode)); 2621} 2622 2623static int selinux_inode_rename(struct inode *old_inode, struct dentry *old_dentry, 2624 struct inode *new_inode, struct dentry *new_dentry) 2625{ 2626 return may_rename(old_inode, old_dentry, new_inode, new_dentry); 2627} 2628 2629static int selinux_inode_readlink(struct dentry *dentry) 2630{ 2631 const struct cred *cred = current_cred(); 2632 2633 return dentry_has_perm(cred, NULL, dentry, FILE__READ); 2634} 2635 2636static int selinux_inode_follow_link(struct dentry *dentry, struct nameidata *nameidata) 2637{ 2638 const struct cred *cred = current_cred(); 2639 2640 return dentry_has_perm(cred, NULL, dentry, FILE__READ); 2641} 2642 2643static int selinux_inode_permission(struct inode *inode, int mask, unsigned flags) 2644{ 2645 const struct cred *cred = current_cred(); 2646 struct common_audit_data ad; 2647 u32 perms; 2648 bool from_access; 2649 2650 from_access = mask & MAY_ACCESS; 2651 mask &= (MAY_READ|MAY_WRITE|MAY_EXEC|MAY_APPEND); 2652 2653 /* No permission to check. Existence test. */ 2654 if (!mask) 2655 return 0; 2656 2657 COMMON_AUDIT_DATA_INIT(&ad, FS); 2658 ad.u.fs.inode = inode; 2659 2660 if (from_access) 2661 ad.selinux_audit_data.auditdeny |= FILE__AUDIT_ACCESS; 2662 2663 perms = file_mask_to_av(inode->i_mode, mask); 2664 2665 return inode_has_perm(cred, inode, perms, &ad, flags); 2666} 2667 2668static int selinux_inode_setattr(struct dentry *dentry, struct iattr *iattr) 2669{ 2670 const struct cred *cred = current_cred(); 2671 unsigned int ia_valid = iattr->ia_valid; 2672 2673 /* ATTR_FORCE is just used for ATTR_KILL_S[UG]ID. */ 2674 if (ia_valid & ATTR_FORCE) { 2675 ia_valid &= ~(ATTR_KILL_SUID | ATTR_KILL_SGID | ATTR_MODE | 2676 ATTR_FORCE); 2677 if (!ia_valid) 2678 return 0; 2679 } 2680 2681 if (ia_valid & (ATTR_MODE | ATTR_UID | ATTR_GID | 2682 ATTR_ATIME_SET | ATTR_MTIME_SET | ATTR_TIMES_SET)) 2683 return dentry_has_perm(cred, NULL, dentry, FILE__SETATTR); 2684 2685 return dentry_has_perm(cred, NULL, dentry, FILE__WRITE); 2686} 2687 2688static int selinux_inode_getattr(struct vfsmount *mnt, struct dentry *dentry) 2689{ 2690 const struct cred *cred = current_cred(); 2691 2692 return dentry_has_perm(cred, mnt, dentry, FILE__GETATTR); 2693} 2694 2695static int selinux_inode_setotherxattr(struct dentry *dentry, const char *name) 2696{ 2697 const struct cred *cred = current_cred(); 2698 2699 if (!strncmp(name, XATTR_SECURITY_PREFIX, 2700 sizeof XATTR_SECURITY_PREFIX - 1)) { 2701 if (!strcmp(name, XATTR_NAME_CAPS)) { 2702 if (!capable(CAP_SETFCAP)) 2703 return -EPERM; 2704 } else if (!capable(CAP_SYS_ADMIN)) { 2705 /* A different attribute in the security namespace. 2706 Restrict to administrator. */ 2707 return -EPERM; 2708 } 2709 } 2710 2711 /* Not an attribute we recognize, so just check the 2712 ordinary setattr permission. */ 2713 return dentry_has_perm(cred, NULL, dentry, FILE__SETATTR); 2714} 2715 2716static int selinux_inode_setxattr(struct dentry *dentry, const char *name, 2717 const void *value, size_t size, int flags) 2718{ 2719 struct inode *inode = dentry->d_inode; 2720 struct inode_security_struct *isec = inode->i_security; 2721 struct superblock_security_struct *sbsec; 2722 struct common_audit_data ad; 2723 u32 newsid, sid = current_sid(); 2724 int rc = 0; 2725 2726 if (strcmp(name, XATTR_NAME_SELINUX)) 2727 return selinux_inode_setotherxattr(dentry, name); 2728 2729 sbsec = inode->i_sb->s_security; 2730 if (!(sbsec->flags & SE_SBLABELSUPP)) 2731 return -EOPNOTSUPP; 2732 2733 if (!inode_owner_or_capable(inode)) 2734 return -EPERM; 2735 2736 COMMON_AUDIT_DATA_INIT(&ad, FS); 2737 ad.u.fs.path.dentry = dentry; 2738 2739 rc = avc_has_perm(sid, isec->sid, isec->sclass, 2740 FILE__RELABELFROM, &ad); 2741 if (rc) 2742 return rc; 2743 2744 rc = security_context_to_sid(value, size, &newsid); 2745 if (rc == -EINVAL) { 2746 if (!capable(CAP_MAC_ADMIN)) 2747 return rc; 2748 rc = security_context_to_sid_force(value, size, &newsid); 2749 } 2750 if (rc) 2751 return rc; 2752 2753 rc = avc_has_perm(sid, newsid, isec->sclass, 2754 FILE__RELABELTO, &ad); 2755 if (rc) 2756 return rc; 2757 2758 rc = security_validate_transition(isec->sid, newsid, sid, 2759 isec->sclass); 2760 if (rc) 2761 return rc; 2762 2763 return avc_has_perm(newsid, 2764 sbsec->sid, 2765 SECCLASS_FILESYSTEM, 2766 FILESYSTEM__ASSOCIATE, 2767 &ad); 2768} 2769 2770static void selinux_inode_post_setxattr(struct dentry *dentry, const char *name, 2771 const void *value, size_t size, 2772 int flags) 2773{ 2774 struct inode *inode = dentry->d_inode; 2775 struct inode_security_struct *isec = inode->i_security; 2776 u32 newsid; 2777 int rc; 2778 2779 if (strcmp(name, XATTR_NAME_SELINUX)) { 2780 /* Not an attribute we recognize, so nothing to do. */ 2781 return; 2782 } 2783 2784 rc = security_context_to_sid_force(value, size, &newsid); 2785 if (rc) { 2786 printk(KERN_ERR "SELinux: unable to map context to SID" 2787 "for (%s, %lu), rc=%d\n", 2788 inode->i_sb->s_id, inode->i_ino, -rc); 2789 return; 2790 } 2791 2792 isec->sid = newsid; 2793 return; 2794} 2795 2796static int selinux_inode_getxattr(struct dentry *dentry, const char *name) 2797{ 2798 const struct cred *cred = current_cred(); 2799 2800 return dentry_has_perm(cred, NULL, dentry, FILE__GETATTR); 2801} 2802 2803static int selinux_inode_listxattr(struct dentry *dentry) 2804{ 2805 const struct cred *cred = current_cred(); 2806 2807 return dentry_has_perm(cred, NULL, dentry, FILE__GETATTR); 2808} 2809 2810static int selinux_inode_removexattr(struct dentry *dentry, const char *name) 2811{ 2812 if (strcmp(name, XATTR_NAME_SELINUX)) 2813 return selinux_inode_setotherxattr(dentry, name); 2814 2815 /* No one is allowed to remove a SELinux security label. 2816 You can change the label, but all data must be labeled. */ 2817 return -EACCES; 2818} 2819 2820/* 2821 * Copy the inode security context value to the user. 2822 * 2823 * Permission check is handled by selinux_inode_getxattr hook. 2824 */ 2825static int selinux_inode_getsecurity(const struct inode *inode, const char *name, void **buffer, bool alloc) 2826{ 2827 u32 size; 2828 int error; 2829 char *context = NULL; 2830 struct inode_security_struct *isec = inode->i_security; 2831 2832 if (strcmp(name, XATTR_SELINUX_SUFFIX)) 2833 return -EOPNOTSUPP; 2834 2835 /* 2836 * If the caller has CAP_MAC_ADMIN, then get the raw context 2837 * value even if it is not defined by current policy; otherwise, 2838 * use the in-core value under current policy. 2839 * Use the non-auditing forms of the permission checks since 2840 * getxattr may be called by unprivileged processes commonly 2841 * and lack of permission just means that we fall back to the 2842 * in-core context value, not a denial. 2843 */ 2844 error = selinux_capable(current, current_cred(), 2845 &init_user_ns, CAP_MAC_ADMIN, 2846 SECURITY_CAP_NOAUDIT); 2847 if (!error) 2848 error = security_sid_to_context_force(isec->sid, &context, 2849 &size); 2850 else 2851 error = security_sid_to_context(isec->sid, &context, &size); 2852 if (error) 2853 return error; 2854 error = size; 2855 if (alloc) { 2856 *buffer = context; 2857 goto out_nofree; 2858 } 2859 kfree(context); 2860out_nofree: 2861 return error; 2862} 2863 2864static int selinux_inode_setsecurity(struct inode *inode, const char *name, 2865 const void *value, size_t size, int flags) 2866{ 2867 struct inode_security_struct *isec = inode->i_security; 2868 u32 newsid; 2869 int rc; 2870 2871 if (strcmp(name, XATTR_SELINUX_SUFFIX)) 2872 return -EOPNOTSUPP; 2873 2874 if (!value || !size) 2875 return -EACCES; 2876 2877 rc = security_context_to_sid((void *)value, size, &newsid); 2878 if (rc) 2879 return rc; 2880 2881 isec->sid = newsid; 2882 isec->initialized = 1; 2883 return 0; 2884} 2885 2886static int selinux_inode_listsecurity(struct inode *inode, char *buffer, size_t buffer_size) 2887{ 2888 const int len = sizeof(XATTR_NAME_SELINUX); 2889 if (buffer && len <= buffer_size) 2890 memcpy(buffer, XATTR_NAME_SELINUX, len); 2891 return len; 2892} 2893 2894static void selinux_inode_getsecid(const struct inode *inode, u32 *secid) 2895{ 2896 struct inode_security_struct *isec = inode->i_security; 2897 *secid = isec->sid; 2898} 2899 2900/* file security operations */ 2901 2902static int selinux_revalidate_file_permission(struct file *file, int mask) 2903{ 2904 const struct cred *cred = current_cred(); 2905 struct inode *inode = file->f_path.dentry->d_inode; 2906 2907 /* file_mask_to_av won't add FILE__WRITE if MAY_APPEND is set */ 2908 if ((file->f_flags & O_APPEND) && (mask & MAY_WRITE)) 2909 mask |= MAY_APPEND; 2910 2911 return file_has_perm(cred, file, 2912 file_mask_to_av(inode->i_mode, mask)); 2913} 2914 2915static int selinux_file_permission(struct file *file, int mask) 2916{ 2917 struct inode *inode = file->f_path.dentry->d_inode; 2918 struct file_security_struct *fsec = file->f_security; 2919 struct inode_security_struct *isec = inode->i_security; 2920 u32 sid = current_sid(); 2921 2922 if (!mask) 2923 /* No permission to check. Existence test. */ 2924 return 0; 2925 2926 if (sid == fsec->sid && fsec->isid == isec->sid && 2927 fsec->pseqno == avc_policy_seqno()) 2928 /* No change since dentry_open check. */ 2929 return 0; 2930 2931 return selinux_revalidate_file_permission(file, mask); 2932} 2933 2934static int selinux_file_alloc_security(struct file *file) 2935{ 2936 return file_alloc_security(file); 2937} 2938 2939static void selinux_file_free_security(struct file *file) 2940{ 2941 file_free_security(file); 2942} 2943 2944static int selinux_file_ioctl(struct file *file, unsigned int cmd, 2945 unsigned long arg) 2946{ 2947 const struct cred *cred = current_cred(); 2948 int error = 0; 2949 2950 switch (cmd) { 2951 case FIONREAD: 2952 /* fall through */ 2953 case FIBMAP: 2954 /* fall through */ 2955 case FIGETBSZ: 2956 /* fall through */ 2957 case EXT2_IOC_GETFLAGS: 2958 /* fall through */ 2959 case EXT2_IOC_GETVERSION: 2960 error = file_has_perm(cred, file, FILE__GETATTR); 2961 break; 2962 2963 case EXT2_IOC_SETFLAGS: 2964 /* fall through */ 2965 case EXT2_IOC_SETVERSION: 2966 error = file_has_perm(cred, file, FILE__SETATTR); 2967 break; 2968 2969 /* sys_ioctl() checks */ 2970 case FIONBIO: 2971 /* fall through */ 2972 case FIOASYNC: 2973 error = file_has_perm(cred, file, 0); 2974 break; 2975 2976 case KDSKBENT: 2977 case KDSKBSENT: 2978 error = task_has_capability(current, cred, CAP_SYS_TTY_CONFIG, 2979 SECURITY_CAP_AUDIT); 2980 break; 2981 2982 /* default case assumes that the command will go 2983 * to the file's ioctl() function. 2984 */ 2985 default: 2986 error = file_has_perm(cred, file, FILE__IOCTL); 2987 } 2988 return error; 2989} 2990 2991static int default_noexec; 2992 2993static int file_map_prot_check(struct file *file, unsigned long prot, int shared) 2994{ 2995 const struct cred *cred = current_cred(); 2996 int rc = 0; 2997 2998 if (default_noexec && 2999 (prot & PROT_EXEC) && (!file || (!shared && (prot & PROT_WRITE)))) { 3000 /* 3001 * We are making executable an anonymous mapping or a 3002 * private file mapping that will also be writable. 3003 * This has an additional check. 3004 */ 3005 rc = cred_has_perm(cred, cred, PROCESS__EXECMEM); 3006 if (rc) 3007 goto error; 3008 } 3009 3010 if (file) { 3011 /* read access is always possible with a mapping */ 3012 u32 av = FILE__READ; 3013 3014 /* write access only matters if the mapping is shared */ 3015 if (shared && (prot & PROT_WRITE)) 3016 av |= FILE__WRITE; 3017 3018 if (prot & PROT_EXEC) 3019 av |= FILE__EXECUTE; 3020 3021 return file_has_perm(cred, file, av); 3022 } 3023 3024error: 3025 return rc; 3026} 3027 3028static int selinux_file_mmap(struct file *file, unsigned long reqprot, 3029 unsigned long prot, unsigned long flags, 3030 unsigned long addr, unsigned long addr_only) 3031{ 3032 int rc = 0; 3033 u32 sid = current_sid(); 3034 3035 /* 3036 * notice that we are intentionally putting the SELinux check before 3037 * the secondary cap_file_mmap check. This is such a likely attempt 3038 * at bad behaviour/exploit that we always want to get the AVC, even 3039 * if DAC would have also denied the operation. 3040 */ 3041 if (addr < CONFIG_LSM_MMAP_MIN_ADDR) { 3042 rc = avc_has_perm(sid, sid, SECCLASS_MEMPROTECT, 3043 MEMPROTECT__MMAP_ZERO, NULL); 3044 if (rc) 3045 return rc; 3046 } 3047 3048 /* do DAC check on address space usage */ 3049 rc = cap_file_mmap(file, reqprot, prot, flags, addr, addr_only); 3050 if (rc || addr_only) 3051 return rc; 3052 3053 if (selinux_checkreqprot) 3054 prot = reqprot; 3055 3056 return file_map_prot_check(file, prot, 3057 (flags & MAP_TYPE) == MAP_SHARED); 3058} 3059 3060static int selinux_file_mprotect(struct vm_area_struct *vma, 3061 unsigned long reqprot, 3062 unsigned long prot) 3063{ 3064 const struct cred *cred = current_cred(); 3065 3066 if (selinux_checkreqprot) 3067 prot = reqprot; 3068 3069 if (default_noexec && 3070 (prot & PROT_EXEC) && !(vma->vm_flags & VM_EXEC)) { 3071 int rc = 0; 3072 if (vma->vm_start >= vma->vm_mm->start_brk && 3073 vma->vm_end <= vma->vm_mm->brk) { 3074 rc = cred_has_perm(cred, cred, PROCESS__EXECHEAP); 3075 } else if (!vma->vm_file && 3076 vma->vm_start <= vma->vm_mm->start_stack && 3077 vma->vm_end >= vma->vm_mm->start_stack) { 3078 rc = current_has_perm(current, PROCESS__EXECSTACK); 3079 } else if (vma->vm_file && vma->anon_vma) { 3080 /* 3081 * We are making executable a file mapping that has 3082 * had some COW done. Since pages might have been 3083 * written, check ability to execute the possibly 3084 * modified content. This typically should only 3085 * occur for text relocations. 3086 */ 3087 rc = file_has_perm(cred, vma->vm_file, FILE__EXECMOD); 3088 } 3089 if (rc) 3090 return rc; 3091 } 3092 3093 return file_map_prot_check(vma->vm_file, prot, vma->vm_flags&VM_SHARED); 3094} 3095 3096static int selinux_file_lock(struct file *file, unsigned int cmd) 3097{ 3098 const struct cred *cred = current_cred(); 3099 3100 return file_has_perm(cred, file, FILE__LOCK); 3101} 3102 3103static int selinux_file_fcntl(struct file *file, unsigned int cmd, 3104 unsigned long arg) 3105{ 3106 const struct cred *cred = current_cred(); 3107 int err = 0; 3108 3109 switch (cmd) { 3110 case F_SETFL: 3111 if (!file->f_path.dentry || !file->f_path.dentry->d_inode) { 3112 err = -EINVAL; 3113 break; 3114 } 3115 3116 if ((file->f_flags & O_APPEND) && !(arg & O_APPEND)) { 3117 err = file_has_perm(cred, file, FILE__WRITE); 3118 break; 3119 } 3120 /* fall through */ 3121 case F_SETOWN: 3122 case F_SETSIG: 3123 case F_GETFL: 3124 case F_GETOWN: 3125 case F_GETSIG: 3126 /* Just check FD__USE permission */ 3127 err = file_has_perm(cred, file, 0); 3128 break; 3129 case F_GETLK: 3130 case F_SETLK: 3131 case F_SETLKW: 3132#if BITS_PER_LONG == 32 3133 case F_GETLK64: 3134 case F_SETLK64: 3135 case F_SETLKW64: 3136#endif 3137 if (!file->f_path.dentry || !file->f_path.dentry->d_inode) { 3138 err = -EINVAL; 3139 break; 3140 } 3141 err = file_has_perm(cred, file, FILE__LOCK); 3142 break; 3143 } 3144 3145 return err; 3146} 3147 3148static int selinux_file_set_fowner(struct file *file) 3149{ 3150 struct file_security_struct *fsec; 3151 3152 fsec = file->f_security; 3153 fsec->fown_sid = current_sid(); 3154 3155 return 0; 3156} 3157 3158static int selinux_file_send_sigiotask(struct task_struct *tsk, 3159 struct fown_struct *fown, int signum) 3160{ 3161 struct file *file; 3162 u32 sid = task_sid(tsk); 3163 u32 perm; 3164 struct file_security_struct *fsec; 3165 3166 /* struct fown_struct is never outside the context of a struct file */ 3167 file = container_of(fown, struct file, f_owner); 3168 3169 fsec = file->f_security; 3170 3171 if (!signum) 3172 perm = signal_to_av(SIGIO); /* as per send_sigio_to_task */ 3173 else 3174 perm = signal_to_av(signum); 3175 3176 return avc_has_perm(fsec->fown_sid, sid, 3177 SECCLASS_PROCESS, perm, NULL); 3178} 3179 3180static int selinux_file_receive(struct file *file) 3181{ 3182 const struct cred *cred = current_cred(); 3183 3184 return file_has_perm(cred, file, file_to_av(file)); 3185} 3186 3187static int selinux_dentry_open(struct file *file, const struct cred *cred) 3188{ 3189 struct file_security_struct *fsec; 3190 struct inode *inode; 3191 struct inode_security_struct *isec; 3192 3193 inode = file->f_path.dentry->d_inode; 3194 fsec = file->f_security; 3195 isec = inode->i_security; 3196 /* 3197 * Save inode label and policy sequence number 3198 * at open-time so that selinux_file_permission 3199 * can determine whether revalidation is necessary. 3200 * Task label is already saved in the file security 3201 * struct as its SID. 3202 */ 3203 fsec->isid = isec->sid; 3204 fsec->pseqno = avc_policy_seqno(); 3205 /* 3206 * Since the inode label or policy seqno may have changed 3207 * between the selinux_inode_permission check and the saving 3208 * of state above, recheck that access is still permitted. 3209 * Otherwise, access might never be revalidated against the 3210 * new inode label or new policy. 3211 * This check is not redundant - do not remove. 3212 */ 3213 return inode_has_perm(cred, inode, open_file_to_av(file), NULL, 0); 3214} 3215 3216/* task security operations */ 3217 3218static int selinux_task_create(unsigned long clone_flags) 3219{ 3220 return current_has_perm(current, PROCESS__FORK); 3221} 3222 3223/* 3224 * allocate the SELinux part of blank credentials 3225 */ 3226static int selinux_cred_alloc_blank(struct cred *cred, gfp_t gfp) 3227{ 3228 struct task_security_struct *tsec; 3229 3230 tsec = kzalloc(sizeof(struct task_security_struct), gfp); 3231 if (!tsec) 3232 return -ENOMEM; 3233 3234 cred->security = tsec; 3235 return 0; 3236} 3237 3238/* 3239 * detach and free the LSM part of a set of credentials 3240 */ 3241static void selinux_cred_free(struct cred *cred) 3242{ 3243 struct task_security_struct *tsec = cred->security; 3244 3245 /* 3246 * cred->security == NULL if security_cred_alloc_blank() or 3247 * security_prepare_creds() returned an error. 3248 */ 3249 BUG_ON(cred->security && (unsigned long) cred->security < PAGE_SIZE); 3250 cred->security = (void *) 0x7UL; 3251 kfree(tsec); 3252} 3253 3254/* 3255 * prepare a new set of credentials for modification 3256 */ 3257static int selinux_cred_prepare(struct cred *new, const struct cred *old, 3258 gfp_t gfp) 3259{ 3260 const struct task_security_struct *old_tsec; 3261 struct task_security_struct *tsec; 3262 3263 old_tsec = old->security; 3264 3265 tsec = kmemdup(old_tsec, sizeof(struct task_security_struct), gfp); 3266 if (!tsec) 3267 return -ENOMEM; 3268 3269 new->security = tsec; 3270 return 0; 3271} 3272 3273/* 3274 * transfer the SELinux data to a blank set of creds 3275 */ 3276static void selinux_cred_transfer(struct cred *new, const struct cred *old) 3277{ 3278 const struct task_security_struct *old_tsec = old->security; 3279 struct task_security_struct *tsec = new->security; 3280 3281 *tsec = *old_tsec; 3282} 3283 3284/* 3285 * set the security data for a kernel service 3286 * - all the creation contexts are set to unlabelled 3287 */ 3288static int selinux_kernel_act_as(struct cred *new, u32 secid) 3289{ 3290 struct task_security_struct *tsec = new->security; 3291 u32 sid = current_sid(); 3292 int ret; 3293 3294 ret = avc_has_perm(sid, secid, 3295 SECCLASS_KERNEL_SERVICE, 3296 KERNEL_SERVICE__USE_AS_OVERRIDE, 3297 NULL); 3298 if (ret == 0) { 3299 tsec->sid = secid; 3300 tsec->create_sid = 0; 3301 tsec->keycreate_sid = 0; 3302 tsec->sockcreate_sid = 0; 3303 } 3304 return ret; 3305} 3306 3307/* 3308 * set the file creation context in a security record to the same as the 3309 * objective context of the specified inode 3310 */ 3311static int selinux_kernel_create_files_as(struct cred *new, struct inode *inode) 3312{ 3313 struct inode_security_struct *isec = inode->i_security; 3314 struct task_security_struct *tsec = new->security; 3315 u32 sid = current_sid(); 3316 int ret; 3317 3318 ret = avc_has_perm(sid, isec->sid, 3319 SECCLASS_KERNEL_SERVICE, 3320 KERNEL_SERVICE__CREATE_FILES_AS, 3321 NULL); 3322 3323 if (ret == 0) 3324 tsec->create_sid = isec->sid; 3325 return ret; 3326} 3327 3328static int selinux_kernel_module_request(char *kmod_name) 3329{ 3330 u32 sid; 3331 struct common_audit_data ad; 3332 3333 sid = task_sid(current); 3334 3335 COMMON_AUDIT_DATA_INIT(&ad, KMOD); 3336 ad.u.kmod_name = kmod_name; 3337 3338 return avc_has_perm(sid, SECINITSID_KERNEL, SECCLASS_SYSTEM, 3339 SYSTEM__MODULE_REQUEST, &ad); 3340} 3341 3342static int selinux_task_setpgid(struct task_struct *p, pid_t pgid) 3343{ 3344 return current_has_perm(p, PROCESS__SETPGID); 3345} 3346 3347static int selinux_task_getpgid(struct task_struct *p) 3348{ 3349 return current_has_perm(p, PROCESS__GETPGID); 3350} 3351 3352static int selinux_task_getsid(struct task_struct *p) 3353{ 3354 return current_has_perm(p, PROCESS__GETSESSION); 3355} 3356 3357static void selinux_task_getsecid(struct task_struct *p, u32 *secid) 3358{ 3359 *secid = task_sid(p); 3360} 3361 3362static int selinux_task_setnice(struct task_struct *p, int nice) 3363{ 3364 int rc; 3365 3366 rc = cap_task_setnice(p, nice); 3367 if (rc) 3368 return rc; 3369 3370 return current_has_perm(p, PROCESS__SETSCHED); 3371} 3372 3373static int selinux_task_setioprio(struct task_struct *p, int ioprio) 3374{ 3375 int rc; 3376 3377 rc = cap_task_setioprio(p, ioprio); 3378 if (rc) 3379 return rc; 3380 3381 return current_has_perm(p, PROCESS__SETSCHED); 3382} 3383 3384static int selinux_task_getioprio(struct task_struct *p) 3385{ 3386 return current_has_perm(p, PROCESS__GETSCHED); 3387} 3388 3389static int selinux_task_setrlimit(struct task_struct *p, unsigned int resource, 3390 struct rlimit *new_rlim) 3391{ 3392 struct rlimit *old_rlim = p->signal->rlim + resource; 3393 3394 /* Control the ability to change the hard limit (whether 3395 lowering or raising it), so that the hard limit can 3396 later be used as a safe reset point for the soft limit 3397 upon context transitions. See selinux_bprm_committing_creds. */ 3398 if (old_rlim->rlim_max != new_rlim->rlim_max) 3399 return current_has_perm(p, PROCESS__SETRLIMIT); 3400 3401 return 0; 3402} 3403 3404static int selinux_task_setscheduler(struct task_struct *p) 3405{ 3406 int rc; 3407 3408 rc = cap_task_setscheduler(p); 3409 if (rc) 3410 return rc; 3411 3412 return current_has_perm(p, PROCESS__SETSCHED); 3413} 3414 3415static int selinux_task_getscheduler(struct task_struct *p) 3416{ 3417 return current_has_perm(p, PROCESS__GETSCHED); 3418} 3419 3420static int selinux_task_movememory(struct task_struct *p) 3421{ 3422 return current_has_perm(p, PROCESS__SETSCHED); 3423} 3424 3425static int selinux_task_kill(struct task_struct *p, struct siginfo *info, 3426 int sig, u32 secid) 3427{ 3428 u32 perm; 3429 int rc; 3430 3431 if (!sig) 3432 perm = PROCESS__SIGNULL; /* null signal; existence test */ 3433 else 3434 perm = signal_to_av(sig); 3435 if (secid) 3436 rc = avc_has_perm(secid, task_sid(p), 3437 SECCLASS_PROCESS, perm, NULL); 3438 else 3439 rc = current_has_perm(p, perm); 3440 return rc; 3441} 3442 3443static int selinux_task_wait(struct task_struct *p) 3444{ 3445 return task_has_perm(p, current, PROCESS__SIGCHLD); 3446} 3447 3448static void selinux_task_to_inode(struct task_struct *p, 3449 struct inode *inode) 3450{ 3451 struct inode_security_struct *isec = inode->i_security; 3452 u32 sid = task_sid(p); 3453 3454 isec->sid = sid; 3455 isec->initialized = 1; 3456} 3457 3458/* Returns error only if unable to parse addresses */ 3459static int selinux_parse_skb_ipv4(struct sk_buff *skb, 3460 struct common_audit_data *ad, u8 *proto) 3461{ 3462 int offset, ihlen, ret = -EINVAL; 3463 struct iphdr _iph, *ih; 3464 3465 offset = skb_network_offset(skb); 3466 ih = skb_header_pointer(skb, offset, sizeof(_iph), &_iph); 3467 if (ih == NULL) 3468 goto out; 3469 3470 ihlen = ih->ihl * 4; 3471 if (ihlen < sizeof(_iph)) 3472 goto out; 3473 3474 ad->u.net.v4info.saddr = ih->saddr; 3475 ad->u.net.v4info.daddr = ih->daddr; 3476 ret = 0; 3477 3478 if (proto) 3479 *proto = ih->protocol; 3480 3481 switch (ih->protocol) { 3482 case IPPROTO_TCP: { 3483 struct tcphdr _tcph, *th; 3484 3485 if (ntohs(ih->frag_off) & IP_OFFSET) 3486 break; 3487 3488 offset += ihlen; 3489 th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph); 3490 if (th == NULL) 3491 break; 3492 3493 ad->u.net.sport = th->source; 3494 ad->u.net.dport = th->dest; 3495 break; 3496 } 3497 3498 case IPPROTO_UDP: { 3499 struct udphdr _udph, *uh; 3500 3501 if (ntohs(ih->frag_off) & IP_OFFSET) 3502 break; 3503 3504 offset += ihlen; 3505 uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph); 3506 if (uh == NULL) 3507 break; 3508 3509 ad->u.net.sport = uh->source; 3510 ad->u.net.dport = uh->dest; 3511 break; 3512 } 3513 3514 case IPPROTO_DCCP: { 3515 struct dccp_hdr _dccph, *dh; 3516 3517 if (ntohs(ih->frag_off) & IP_OFFSET) 3518 break; 3519 3520 offset += ihlen; 3521 dh = skb_header_pointer(skb, offset, sizeof(_dccph), &_dccph); 3522 if (dh == NULL) 3523 break; 3524 3525 ad->u.net.sport = dh->dccph_sport; 3526 ad->u.net.dport = dh->dccph_dport; 3527 break; 3528 } 3529 3530 default: 3531 break; 3532 } 3533out: 3534 return ret; 3535} 3536 3537#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE) 3538 3539/* Returns error only if unable to parse addresses */ 3540static int selinux_parse_skb_ipv6(struct sk_buff *skb, 3541 struct common_audit_data *ad, u8 *proto) 3542{ 3543 u8 nexthdr; 3544 int ret = -EINVAL, offset; 3545 struct ipv6hdr _ipv6h, *ip6; 3546 3547 offset = skb_network_offset(skb); 3548 ip6 = skb_header_pointer(skb, offset, sizeof(_ipv6h), &_ipv6h); 3549 if (ip6 == NULL) 3550 goto out; 3551 3552 ipv6_addr_copy(&ad->u.net.v6info.saddr, &ip6->saddr); 3553 ipv6_addr_copy(&ad->u.net.v6info.daddr, &ip6->daddr); 3554 ret = 0; 3555 3556 nexthdr = ip6->nexthdr; 3557 offset += sizeof(_ipv6h); 3558 offset = ipv6_skip_exthdr(skb, offset, &nexthdr); 3559 if (offset < 0) 3560 goto out; 3561 3562 if (proto) 3563 *proto = nexthdr; 3564 3565 switch (nexthdr) { 3566 case IPPROTO_TCP: { 3567 struct tcphdr _tcph, *th; 3568 3569 th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph); 3570 if (th == NULL) 3571 break; 3572 3573 ad->u.net.sport = th->source; 3574 ad->u.net.dport = th->dest; 3575 break; 3576 } 3577 3578 case IPPROTO_UDP: { 3579 struct udphdr _udph, *uh; 3580 3581 uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph); 3582 if (uh == NULL) 3583 break; 3584 3585 ad->u.net.sport = uh->source; 3586 ad->u.net.dport = uh->dest; 3587 break; 3588 } 3589 3590 case IPPROTO_DCCP: { 3591 struct dccp_hdr _dccph, *dh; 3592 3593 dh = skb_header_pointer(skb, offset, sizeof(_dccph), &_dccph); 3594 if (dh == NULL) 3595 break; 3596 3597 ad->u.net.sport = dh->dccph_sport; 3598 ad->u.net.dport = dh->dccph_dport; 3599 break; 3600 } 3601 3602 /* includes fragments */ 3603 default: 3604 break; 3605 } 3606out: 3607 return ret; 3608} 3609 3610#endif /* IPV6 */ 3611 3612static int selinux_parse_skb(struct sk_buff *skb, struct common_audit_data *ad, 3613 char **_addrp, int src, u8 *proto) 3614{ 3615 char *addrp; 3616 int ret; 3617 3618 switch (ad->u.net.family) { 3619 case PF_INET: 3620 ret = selinux_parse_skb_ipv4(skb, ad, proto); 3621 if (ret) 3622 goto parse_error; 3623 addrp = (char *)(src ? &ad->u.net.v4info.saddr : 3624 &ad->u.net.v4info.daddr); 3625 goto okay; 3626 3627#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE) 3628 case PF_INET6: 3629 ret = selinux_parse_skb_ipv6(skb, ad, proto); 3630 if (ret) 3631 goto parse_error; 3632 addrp = (char *)(src ? &ad->u.net.v6info.saddr : 3633 &ad->u.net.v6info.daddr); 3634 goto okay; 3635#endif /* IPV6 */ 3636 default: 3637 addrp = NULL; 3638 goto okay; 3639 } 3640 3641parse_error: 3642 printk(KERN_WARNING 3643 "SELinux: failure in selinux_parse_skb()," 3644 " unable to parse packet\n"); 3645 return ret; 3646 3647okay: 3648 if (_addrp) 3649 *_addrp = addrp; 3650 return 0; 3651} 3652 3653/** 3654 * selinux_skb_peerlbl_sid - Determine the peer label of a packet 3655 * @skb: the packet 3656 * @family: protocol family 3657 * @sid: the packet's peer label SID 3658 * 3659 * Description: 3660 * Check the various different forms of network peer labeling and determine 3661 * the peer label/SID for the packet; most of the magic actually occurs in 3662 * the security server function security_net_peersid_cmp(). The function 3663 * returns zero if the value in @sid is valid (although it may be SECSID_NULL) 3664 * or -EACCES if @sid is invalid due to inconsistencies with the different 3665 * peer labels. 3666 * 3667 */ 3668static int selinux_skb_peerlbl_sid(struct sk_buff *skb, u16 family, u32 *sid) 3669{ 3670 int err; 3671 u32 xfrm_sid; 3672 u32 nlbl_sid; 3673 u32 nlbl_type; 3674 3675 selinux_skb_xfrm_sid(skb, &xfrm_sid); 3676 selinux_netlbl_skbuff_getsid(skb, family, &nlbl_type, &nlbl_sid); 3677 3678 err = security_net_peersid_resolve(nlbl_sid, nlbl_type, xfrm_sid, sid); 3679 if (unlikely(err)) { 3680 printk(KERN_WARNING 3681 "SELinux: failure in selinux_skb_peerlbl_sid()," 3682 " unable to determine packet's peer label\n"); 3683 return -EACCES; 3684 } 3685 3686 return 0; 3687} 3688 3689/* socket security operations */ 3690 3691static int socket_sockcreate_sid(const struct task_security_struct *tsec, 3692 u16 secclass, u32 *socksid) 3693{ 3694 if (tsec->sockcreate_sid > SECSID_NULL) { 3695 *socksid = tsec->sockcreate_sid; 3696 return 0; 3697 } 3698 3699 return security_transition_sid(tsec->sid, tsec->sid, secclass, NULL, 3700 socksid); 3701} 3702 3703static int sock_has_perm(struct task_struct *task, struct sock *sk, u32 perms) 3704{ 3705 struct sk_security_struct *sksec = sk->sk_security; 3706 struct common_audit_data ad; 3707 u32 tsid = task_sid(task); 3708 3709 if (sksec->sid == SECINITSID_KERNEL) 3710 return 0; 3711 3712 COMMON_AUDIT_DATA_INIT(&ad, NET); 3713 ad.u.net.sk = sk; 3714 3715 return avc_has_perm(tsid, sksec->sid, sksec->sclass, perms, &ad); 3716} 3717 3718static int selinux_socket_create(int family, int type, 3719 int protocol, int kern) 3720{ 3721 const struct task_security_struct *tsec = current_security(); 3722 u32 newsid; 3723 u16 secclass; 3724 int rc; 3725 3726 if (kern) 3727 return 0; 3728 3729 secclass = socket_type_to_security_class(family, type, protocol); 3730 rc = socket_sockcreate_sid(tsec, secclass, &newsid); 3731 if (rc) 3732 return rc; 3733 3734 return avc_has_perm(tsec->sid, newsid, secclass, SOCKET__CREATE, NULL); 3735} 3736 3737static int selinux_socket_post_create(struct socket *sock, int family, 3738 int type, int protocol, int kern) 3739{ 3740 const struct task_security_struct *tsec = current_security(); 3741 struct inode_security_struct *isec = SOCK_INODE(sock)->i_security; 3742 struct sk_security_struct *sksec; 3743 int err = 0; 3744 3745 isec->sclass = socket_type_to_security_class(family, type, protocol); 3746 3747 if (kern) 3748 isec->sid = SECINITSID_KERNEL; 3749 else { 3750 err = socket_sockcreate_sid(tsec, isec->sclass, &(isec->sid)); 3751 if (err) 3752 return err; 3753 } 3754 3755 isec->initialized = 1; 3756 3757 if (sock->sk) { 3758 sksec = sock->sk->sk_security; 3759 sksec->sid = isec->sid; 3760 sksec->sclass = isec->sclass; 3761 err = selinux_netlbl_socket_post_create(sock->sk, family); 3762 } 3763 3764 return err; 3765} 3766 3767/* Range of port numbers used to automatically bind. 3768 Need to determine whether we should perform a name_bind 3769 permission check between the socket and the port number. */ 3770 3771static int selinux_socket_bind(struct socket *sock, struct sockaddr *address, int addrlen) 3772{ 3773 struct sock *sk = sock->sk; 3774 u16 family; 3775 int err; 3776 3777 err = sock_has_perm(current, sk, SOCKET__BIND); 3778 if (err) 3779 goto out; 3780 3781 /* 3782 * If PF_INET or PF_INET6, check name_bind permission for the port. 3783 * Multiple address binding for SCTP is not supported yet: we just 3784 * check the first address now. 3785 */ 3786 family = sk->sk_family; 3787 if (family == PF_INET || family == PF_INET6) { 3788 char *addrp; 3789 struct sk_security_struct *sksec = sk->sk_security; 3790 struct common_audit_data ad; 3791 struct sockaddr_in *addr4 = NULL; 3792 struct sockaddr_in6 *addr6 = NULL; 3793 unsigned short snum; 3794 u32 sid, node_perm; 3795 3796 if (family == PF_INET) { 3797 addr4 = (struct sockaddr_in *)address; 3798 snum = ntohs(addr4->sin_port); 3799 addrp = (char *)&addr4->sin_addr.s_addr; 3800 } else { 3801 addr6 = (struct sockaddr_in6 *)address; 3802 snum = ntohs(addr6->sin6_port); 3803 addrp = (char *)&addr6->sin6_addr.s6_addr; 3804 } 3805 3806 if (snum) { 3807 int low, high; 3808 3809 inet_get_local_port_range(&low, &high); 3810 3811 if (snum < max(PROT_SOCK, low) || snum > high) { 3812 err = sel_netport_sid(sk->sk_protocol, 3813 snum, &sid); 3814 if (err) 3815 goto out; 3816 COMMON_AUDIT_DATA_INIT(&ad, NET); 3817 ad.u.net.sport = htons(snum); 3818 ad.u.net.family = family; 3819 err = avc_has_perm(sksec->sid, sid, 3820 sksec->sclass, 3821 SOCKET__NAME_BIND, &ad); 3822 if (err) 3823 goto out; 3824 } 3825 } 3826 3827 switch (sksec->sclass) { 3828 case SECCLASS_TCP_SOCKET: 3829 node_perm = TCP_SOCKET__NODE_BIND; 3830 break; 3831 3832 case SECCLASS_UDP_SOCKET: 3833 node_perm = UDP_SOCKET__NODE_BIND; 3834 break; 3835 3836 case SECCLASS_DCCP_SOCKET: 3837 node_perm = DCCP_SOCKET__NODE_BIND; 3838 break; 3839 3840 default: 3841 node_perm = RAWIP_SOCKET__NODE_BIND; 3842 break; 3843 } 3844 3845 err = sel_netnode_sid(addrp, family, &sid); 3846 if (err) 3847 goto out; 3848 3849 COMMON_AUDIT_DATA_INIT(&ad, NET); 3850 ad.u.net.sport = htons(snum); 3851 ad.u.net.family = family; 3852 3853 if (family == PF_INET) 3854 ad.u.net.v4info.saddr = addr4->sin_addr.s_addr; 3855 else 3856 ipv6_addr_copy(&ad.u.net.v6info.saddr, &addr6->sin6_addr); 3857 3858 err = avc_has_perm(sksec->sid, sid, 3859 sksec->sclass, node_perm, &ad); 3860 if (err) 3861 goto out; 3862 } 3863out: 3864 return err; 3865} 3866 3867static int selinux_socket_connect(struct socket *sock, struct sockaddr *address, int addrlen) 3868{ 3869 struct sock *sk = sock->sk; 3870 struct sk_security_struct *sksec = sk->sk_security; 3871 int err; 3872 3873 err = sock_has_perm(current, sk, SOCKET__CONNECT); 3874 if (err) 3875 return err; 3876 3877 /* 3878 * If a TCP or DCCP socket, check name_connect permission for the port. 3879 */ 3880 if (sksec->sclass == SECCLASS_TCP_SOCKET || 3881 sksec->sclass == SECCLASS_DCCP_SOCKET) { 3882 struct common_audit_data ad; 3883 struct sockaddr_in *addr4 = NULL; 3884 struct sockaddr_in6 *addr6 = NULL; 3885 unsigned short snum; 3886 u32 sid, perm; 3887 3888 if (sk->sk_family == PF_INET) { 3889 addr4 = (struct sockaddr_in *)address; 3890 if (addrlen < sizeof(struct sockaddr_in)) 3891 return -EINVAL; 3892 snum = ntohs(addr4->sin_port); 3893 } else { 3894 addr6 = (struct sockaddr_in6 *)address; 3895 if (addrlen < SIN6_LEN_RFC2133) 3896 return -EINVAL; 3897 snum = ntohs(addr6->sin6_port); 3898 } 3899 3900 err = sel_netport_sid(sk->sk_protocol, snum, &sid); 3901 if (err) 3902 goto out; 3903 3904 perm = (sksec->sclass == SECCLASS_TCP_SOCKET) ? 3905 TCP_SOCKET__NAME_CONNECT : DCCP_SOCKET__NAME_CONNECT; 3906 3907 COMMON_AUDIT_DATA_INIT(&ad, NET); 3908 ad.u.net.dport = htons(snum); 3909 ad.u.net.family = sk->sk_family; 3910 err = avc_has_perm(sksec->sid, sid, sksec->sclass, perm, &ad); 3911 if (err) 3912 goto out; 3913 } 3914 3915 err = selinux_netlbl_socket_connect(sk, address); 3916 3917out: 3918 return err; 3919} 3920 3921static int selinux_socket_listen(struct socket *sock, int backlog) 3922{ 3923 return sock_has_perm(current, sock->sk, SOCKET__LISTEN); 3924} 3925 3926static int selinux_socket_accept(struct socket *sock, struct socket *newsock) 3927{ 3928 int err; 3929 struct inode_security_struct *isec; 3930 struct inode_security_struct *newisec; 3931 3932 err = sock_has_perm(current, sock->sk, SOCKET__ACCEPT); 3933 if (err) 3934 return err; 3935 3936 newisec = SOCK_INODE(newsock)->i_security; 3937 3938 isec = SOCK_INODE(sock)->i_security; 3939 newisec->sclass = isec->sclass; 3940 newisec->sid = isec->sid; 3941 newisec->initialized = 1; 3942 3943 return 0; 3944} 3945 3946static int selinux_socket_sendmsg(struct socket *sock, struct msghdr *msg, 3947 int size) 3948{ 3949 return sock_has_perm(current, sock->sk, SOCKET__WRITE); 3950} 3951 3952static int selinux_socket_recvmsg(struct socket *sock, struct msghdr *msg, 3953 int size, int flags) 3954{ 3955 return sock_has_perm(current, sock->sk, SOCKET__READ); 3956} 3957 3958static int selinux_socket_getsockname(struct socket *sock) 3959{ 3960 return sock_has_perm(current, sock->sk, SOCKET__GETATTR); 3961} 3962 3963static int selinux_socket_getpeername(struct socket *sock) 3964{ 3965 return sock_has_perm(current, sock->sk, SOCKET__GETATTR); 3966} 3967 3968static int selinux_socket_setsockopt(struct socket *sock, int level, int optname) 3969{ 3970 int err; 3971 3972 err = sock_has_perm(current, sock->sk, SOCKET__SETOPT); 3973 if (err) 3974 return err; 3975 3976 return selinux_netlbl_socket_setsockopt(sock, level, optname); 3977} 3978 3979static int selinux_socket_getsockopt(struct socket *sock, int level, 3980 int optname) 3981{ 3982 return sock_has_perm(current, sock->sk, SOCKET__GETOPT); 3983} 3984 3985static int selinux_socket_shutdown(struct socket *sock, int how) 3986{ 3987 return sock_has_perm(current, sock->sk, SOCKET__SHUTDOWN); 3988} 3989 3990static int selinux_socket_unix_stream_connect(struct sock *sock, 3991 struct sock *other, 3992 struct sock *newsk) 3993{ 3994 struct sk_security_struct *sksec_sock = sock->sk_security; 3995 struct sk_security_struct *sksec_other = other->sk_security; 3996 struct sk_security_struct *sksec_new = newsk->sk_security; 3997 struct common_audit_data ad; 3998 int err; 3999 4000 COMMON_AUDIT_DATA_INIT(&ad, NET); 4001 ad.u.net.sk = other; 4002 4003 err = avc_has_perm(sksec_sock->sid, sksec_other->sid, 4004 sksec_other->sclass, 4005 UNIX_STREAM_SOCKET__CONNECTTO, &ad); 4006 if (err) 4007 return err; 4008 4009 /* server child socket */ 4010 sksec_new->peer_sid = sksec_sock->sid; 4011 err = security_sid_mls_copy(sksec_other->sid, sksec_sock->sid, 4012 &sksec_new->sid); 4013 if (err) 4014 return err; 4015 4016 /* connecting socket */ 4017 sksec_sock->peer_sid = sksec_new->sid; 4018 4019 return 0; 4020} 4021 4022static int selinux_socket_unix_may_send(struct socket *sock, 4023 struct socket *other) 4024{ 4025 struct sk_security_struct *ssec = sock->sk->sk_security; 4026 struct sk_security_struct *osec = other->sk->sk_security; 4027 struct common_audit_data ad; 4028 4029 COMMON_AUDIT_DATA_INIT(&ad, NET); 4030 ad.u.net.sk = other->sk; 4031 4032 return avc_has_perm(ssec->sid, osec->sid, osec->sclass, SOCKET__SENDTO, 4033 &ad); 4034} 4035 4036static int selinux_inet_sys_rcv_skb(int ifindex, char *addrp, u16 family, 4037 u32 peer_sid, 4038 struct common_audit_data *ad) 4039{ 4040 int err; 4041 u32 if_sid; 4042 u32 node_sid; 4043 4044 err = sel_netif_sid(ifindex, &if_sid); 4045 if (err) 4046 return err; 4047 err = avc_has_perm(peer_sid, if_sid, 4048 SECCLASS_NETIF, NETIF__INGRESS, ad); 4049 if (err) 4050 return err; 4051 4052 err = sel_netnode_sid(addrp, family, &node_sid); 4053 if (err) 4054 return err; 4055 return avc_has_perm(peer_sid, node_sid, 4056 SECCLASS_NODE, NODE__RECVFROM, ad); 4057} 4058 4059static int selinux_sock_rcv_skb_compat(struct sock *sk, struct sk_buff *skb, 4060 u16 family) 4061{ 4062 int err = 0; 4063 struct sk_security_struct *sksec = sk->sk_security; 4064 u32 sk_sid = sksec->sid; 4065 struct common_audit_data ad; 4066 char *addrp; 4067 4068 COMMON_AUDIT_DATA_INIT(&ad, NET); 4069 ad.u.net.netif = skb->skb_iif; 4070 ad.u.net.family = family; 4071 err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL); 4072 if (err) 4073 return err; 4074 4075 if (selinux_secmark_enabled()) { 4076 err = avc_has_perm(sk_sid, skb->secmark, SECCLASS_PACKET, 4077 PACKET__RECV, &ad); 4078 if (err) 4079 return err; 4080 } 4081 4082 err = selinux_netlbl_sock_rcv_skb(sksec, skb, family, &ad); 4083 if (err) 4084 return err; 4085 err = selinux_xfrm_sock_rcv_skb(sksec->sid, skb, &ad); 4086 4087 return err; 4088} 4089 4090static int selinux_socket_sock_rcv_skb(struct sock *sk, struct sk_buff *skb) 4091{ 4092 int err; 4093 struct sk_security_struct *sksec = sk->sk_security; 4094 u16 family = sk->sk_family; 4095 u32 sk_sid = sksec->sid; 4096 struct common_audit_data ad; 4097 char *addrp; 4098 u8 secmark_active; 4099 u8 peerlbl_active; 4100 4101 if (family != PF_INET && family != PF_INET6) 4102 return 0; 4103 4104 /* Handle mapped IPv4 packets arriving via IPv6 sockets */ 4105 if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP)) 4106 family = PF_INET; 4107 4108 /* If any sort of compatibility mode is enabled then handoff processing 4109 * to the selinux_sock_rcv_skb_compat() function to deal with the 4110 * special handling. We do this in an attempt to keep this function 4111 * as fast and as clean as possible. */ 4112 if (!selinux_policycap_netpeer) 4113 return selinux_sock_rcv_skb_compat(sk, skb, family); 4114 4115 secmark_active = selinux_secmark_enabled(); 4116 peerlbl_active = netlbl_enabled() || selinux_xfrm_enabled(); 4117 if (!secmark_active && !peerlbl_active) 4118 return 0; 4119 4120 COMMON_AUDIT_DATA_INIT(&ad, NET); 4121 ad.u.net.netif = skb->skb_iif; 4122 ad.u.net.family = family; 4123 err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL); 4124 if (err) 4125 return err; 4126 4127 if (peerlbl_active) { 4128 u32 peer_sid; 4129 4130 err = selinux_skb_peerlbl_sid(skb, family, &peer_sid); 4131 if (err) 4132 return err; 4133 err = selinux_inet_sys_rcv_skb(skb->skb_iif, addrp, family, 4134 peer_sid, &ad); 4135 if (err) { 4136 selinux_netlbl_err(skb, err, 0); 4137 return err; 4138 } 4139 err = avc_has_perm(sk_sid, peer_sid, SECCLASS_PEER, 4140 PEER__RECV, &ad); 4141 if (err) 4142 selinux_netlbl_err(skb, err, 0); 4143 } 4144 4145 if (secmark_active) { 4146 err = avc_has_perm(sk_sid, skb->secmark, SECCLASS_PACKET, 4147 PACKET__RECV, &ad); 4148 if (err) 4149 return err; 4150 } 4151 4152 return err; 4153} 4154 4155static int selinux_socket_getpeersec_stream(struct socket *sock, char __user *optval, 4156 int __user *optlen, unsigned len) 4157{ 4158 int err = 0; 4159 char *scontext; 4160 u32 scontext_len; 4161 struct sk_security_struct *sksec = sock->sk->sk_security; 4162 u32 peer_sid = SECSID_NULL; 4163 4164 if (sksec->sclass == SECCLASS_UNIX_STREAM_SOCKET || 4165 sksec->sclass == SECCLASS_TCP_SOCKET) 4166 peer_sid = sksec->peer_sid; 4167 if (peer_sid == SECSID_NULL) 4168 return -ENOPROTOOPT; 4169 4170 err = security_sid_to_context(peer_sid, &scontext, &scontext_len); 4171 if (err) 4172 return err; 4173 4174 if (scontext_len > len) { 4175 err = -ERANGE; 4176 goto out_len; 4177 } 4178 4179 if (copy_to_user(optval, scontext, scontext_len)) 4180 err = -EFAULT; 4181 4182out_len: 4183 if (put_user(scontext_len, optlen)) 4184 err = -EFAULT; 4185 kfree(scontext); 4186 return err; 4187} 4188 4189static int selinux_socket_getpeersec_dgram(struct socket *sock, struct sk_buff *skb, u32 *secid) 4190{ 4191 u32 peer_secid = SECSID_NULL; 4192 u16 family; 4193 4194 if (skb && skb->protocol == htons(ETH_P_IP)) 4195 family = PF_INET; 4196 else if (skb && skb->protocol == htons(ETH_P_IPV6)) 4197 family = PF_INET6; 4198 else if (sock) 4199 family = sock->sk->sk_family; 4200 else 4201 goto out; 4202 4203 if (sock && family == PF_UNIX) 4204 selinux_inode_getsecid(SOCK_INODE(sock), &peer_secid); 4205 else if (skb) 4206 selinux_skb_peerlbl_sid(skb, family, &peer_secid); 4207 4208out: 4209 *secid = peer_secid; 4210 if (peer_secid == SECSID_NULL) 4211 return -EINVAL; 4212 return 0; 4213} 4214 4215static int selinux_sk_alloc_security(struct sock *sk, int family, gfp_t priority) 4216{ 4217 struct sk_security_struct *sksec; 4218 4219 sksec = kzalloc(sizeof(*sksec), priority); 4220 if (!sksec) 4221 return -ENOMEM; 4222 4223 sksec->peer_sid = SECINITSID_UNLABELED; 4224 sksec->sid = SECINITSID_UNLABELED; 4225 selinux_netlbl_sk_security_reset(sksec); 4226 sk->sk_security = sksec; 4227 4228 return 0; 4229} 4230 4231static void selinux_sk_free_security(struct sock *sk) 4232{ 4233 struct sk_security_struct *sksec = sk->sk_security; 4234 4235 sk->sk_security = NULL; 4236 selinux_netlbl_sk_security_free(sksec); 4237 kfree(sksec); 4238} 4239 4240static void selinux_sk_clone_security(const struct sock *sk, struct sock *newsk) 4241{ 4242 struct sk_security_struct *sksec = sk->sk_security; 4243 struct sk_security_struct *newsksec = newsk->sk_security; 4244 4245 newsksec->sid = sksec->sid; 4246 newsksec->peer_sid = sksec->peer_sid; 4247 newsksec->sclass = sksec->sclass; 4248 4249 selinux_netlbl_sk_security_reset(newsksec); 4250} 4251 4252static void selinux_sk_getsecid(struct sock *sk, u32 *secid) 4253{ 4254 if (!sk) 4255 *secid = SECINITSID_ANY_SOCKET; 4256 else { 4257 struct sk_security_struct *sksec = sk->sk_security; 4258 4259 *secid = sksec->sid; 4260 } 4261} 4262 4263static void selinux_sock_graft(struct sock *sk, struct socket *parent) 4264{ 4265 struct inode_security_struct *isec = SOCK_INODE(parent)->i_security; 4266 struct sk_security_struct *sksec = sk->sk_security; 4267 4268 if (sk->sk_family == PF_INET || sk->sk_family == PF_INET6 || 4269 sk->sk_family == PF_UNIX) 4270 isec->sid = sksec->sid; 4271 sksec->sclass = isec->sclass; 4272} 4273 4274static int selinux_inet_conn_request(struct sock *sk, struct sk_buff *skb, 4275 struct request_sock *req) 4276{ 4277 struct sk_security_struct *sksec = sk->sk_security; 4278 int err; 4279 u16 family = sk->sk_family; 4280 u32 newsid; 4281 u32 peersid; 4282 4283 /* handle mapped IPv4 packets arriving via IPv6 sockets */ 4284 if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP)) 4285 family = PF_INET; 4286 4287 err = selinux_skb_peerlbl_sid(skb, family, &peersid); 4288 if (err) 4289 return err; 4290 if (peersid == SECSID_NULL) { 4291 req->secid = sksec->sid; 4292 req->peer_secid = SECSID_NULL; 4293 } else { 4294 err = security_sid_mls_copy(sksec->sid, peersid, &newsid); 4295 if (err) 4296 return err; 4297 req->secid = newsid; 4298 req->peer_secid = peersid; 4299 } 4300 4301 return selinux_netlbl_inet_conn_request(req, family); 4302} 4303 4304static void selinux_inet_csk_clone(struct sock *newsk, 4305 const struct request_sock *req) 4306{ 4307 struct sk_security_struct *newsksec = newsk->sk_security; 4308 4309 newsksec->sid = req->secid; 4310 newsksec->peer_sid = req->peer_secid; 4311 /* NOTE: Ideally, we should also get the isec->sid for the 4312 new socket in sync, but we don't have the isec available yet. 4313 So we will wait until sock_graft to do it, by which 4314 time it will have been created and available. */ 4315 4316 /* We don't need to take any sort of lock here as we are the only 4317 * thread with access to newsksec */ 4318 selinux_netlbl_inet_csk_clone(newsk, req->rsk_ops->family); 4319} 4320 4321static void selinux_inet_conn_established(struct sock *sk, struct sk_buff *skb) 4322{ 4323 u16 family = sk->sk_family; 4324 struct sk_security_struct *sksec = sk->sk_security; 4325 4326 /* handle mapped IPv4 packets arriving via IPv6 sockets */ 4327 if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP)) 4328 family = PF_INET; 4329 4330 selinux_skb_peerlbl_sid(skb, family, &sksec->peer_sid); 4331} 4332 4333static int selinux_secmark_relabel_packet(u32 sid) 4334{ 4335 const struct task_security_struct *__tsec; 4336 u32 tsid; 4337 4338 __tsec = current_security(); 4339 tsid = __tsec->sid; 4340 4341 return avc_has_perm(tsid, sid, SECCLASS_PACKET, PACKET__RELABELTO, NULL); 4342} 4343 4344static void selinux_secmark_refcount_inc(void) 4345{ 4346 atomic_inc(&selinux_secmark_refcount); 4347} 4348 4349static void selinux_secmark_refcount_dec(void) 4350{ 4351 atomic_dec(&selinux_secmark_refcount); 4352} 4353 4354static void selinux_req_classify_flow(const struct request_sock *req, 4355 struct flowi *fl) 4356{ 4357 fl->flowi_secid = req->secid; 4358} 4359 4360static int selinux_tun_dev_create(void) 4361{ 4362 u32 sid = current_sid(); 4363 4364 /* we aren't taking into account the "sockcreate" SID since the socket 4365 * that is being created here is not a socket in the traditional sense, 4366 * instead it is a private sock, accessible only to the kernel, and 4367 * representing a wide range of network traffic spanning multiple 4368 * connections unlike traditional sockets - check the TUN driver to 4369 * get a better understanding of why this socket is special */ 4370 4371 return avc_has_perm(sid, sid, SECCLASS_TUN_SOCKET, TUN_SOCKET__CREATE, 4372 NULL); 4373} 4374 4375static void selinux_tun_dev_post_create(struct sock *sk) 4376{ 4377 struct sk_security_struct *sksec = sk->sk_security; 4378 4379 /* we don't currently perform any NetLabel based labeling here and it 4380 * isn't clear that we would want to do so anyway; while we could apply 4381 * labeling without the support of the TUN user the resulting labeled 4382 * traffic from the other end of the connection would almost certainly 4383 * cause confusion to the TUN user that had no idea network labeling 4384 * protocols were being used */ 4385 4386 /* see the comments in selinux_tun_dev_create() about why we don't use 4387 * the sockcreate SID here */ 4388 4389 sksec->sid = current_sid(); 4390 sksec->sclass = SECCLASS_TUN_SOCKET; 4391} 4392 4393static int selinux_tun_dev_attach(struct sock *sk) 4394{ 4395 struct sk_security_struct *sksec = sk->sk_security; 4396 u32 sid = current_sid(); 4397 int err; 4398 4399 err = avc_has_perm(sid, sksec->sid, SECCLASS_TUN_SOCKET, 4400 TUN_SOCKET__RELABELFROM, NULL); 4401 if (err) 4402 return err; 4403 err = avc_has_perm(sid, sid, SECCLASS_TUN_SOCKET, 4404 TUN_SOCKET__RELABELTO, NULL); 4405 if (err) 4406 return err; 4407 4408 sksec->sid = sid; 4409 4410 return 0; 4411} 4412 4413static int selinux_nlmsg_perm(struct sock *sk, struct sk_buff *skb) 4414{ 4415 int err = 0; 4416 u32 perm; 4417 struct nlmsghdr *nlh; 4418 struct sk_security_struct *sksec = sk->sk_security; 4419 4420 if (skb->len < NLMSG_SPACE(0)) { 4421 err = -EINVAL; 4422 goto out; 4423 } 4424 nlh = nlmsg_hdr(skb); 4425 4426 err = selinux_nlmsg_lookup(sksec->sclass, nlh->nlmsg_type, &perm); 4427 if (err) { 4428 if (err == -EINVAL) { 4429 audit_log(current->audit_context, GFP_KERNEL, AUDIT_SELINUX_ERR, 4430 "SELinux: unrecognized netlink message" 4431 " type=%hu for sclass=%hu\n", 4432 nlh->nlmsg_type, sksec->sclass); 4433 if (!selinux_enforcing || security_get_allow_unknown()) 4434 err = 0; 4435 } 4436 4437 /* Ignore */ 4438 if (err == -ENOENT) 4439 err = 0; 4440 goto out; 4441 } 4442 4443 err = sock_has_perm(current, sk, perm); 4444out: 4445 return err; 4446} 4447 4448#ifdef CONFIG_NETFILTER 4449 4450static unsigned int selinux_ip_forward(struct sk_buff *skb, int ifindex, 4451 u16 family) 4452{ 4453 int err; 4454 char *addrp; 4455 u32 peer_sid; 4456 struct common_audit_data ad; 4457 u8 secmark_active; 4458 u8 netlbl_active; 4459 u8 peerlbl_active; 4460 4461 if (!selinux_policycap_netpeer) 4462 return NF_ACCEPT; 4463 4464 secmark_active = selinux_secmark_enabled(); 4465 netlbl_active = netlbl_enabled(); 4466 peerlbl_active = netlbl_active || selinux_xfrm_enabled(); 4467 if (!secmark_active && !peerlbl_active) 4468 return NF_ACCEPT; 4469 4470 if (selinux_skb_peerlbl_sid(skb, family, &peer_sid) != 0) 4471 return NF_DROP; 4472 4473 COMMON_AUDIT_DATA_INIT(&ad, NET); 4474 ad.u.net.netif = ifindex; 4475 ad.u.net.family = family; 4476 if (selinux_parse_skb(skb, &ad, &addrp, 1, NULL) != 0) 4477 return NF_DROP; 4478 4479 if (peerlbl_active) { 4480 err = selinux_inet_sys_rcv_skb(ifindex, addrp, family, 4481 peer_sid, &ad); 4482 if (err) { 4483 selinux_netlbl_err(skb, err, 1); 4484 return NF_DROP; 4485 } 4486 } 4487 4488 if (secmark_active) 4489 if (avc_has_perm(peer_sid, skb->secmark, 4490 SECCLASS_PACKET, PACKET__FORWARD_IN, &ad)) 4491 return NF_DROP; 4492 4493 if (netlbl_active) 4494 /* we do this in the FORWARD path and not the POST_ROUTING 4495 * path because we want to make sure we apply the necessary 4496 * labeling before IPsec is applied so we can leverage AH 4497 * protection */ 4498 if (selinux_netlbl_skbuff_setsid(skb, family, peer_sid) != 0) 4499 return NF_DROP; 4500 4501 return NF_ACCEPT; 4502} 4503 4504static unsigned int selinux_ipv4_forward(unsigned int hooknum, 4505 struct sk_buff *skb, 4506 const struct net_device *in, 4507 const struct net_device *out, 4508 int (*okfn)(struct sk_buff *)) 4509{ 4510 return selinux_ip_forward(skb, in->ifindex, PF_INET); 4511} 4512 4513#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE) 4514static unsigned int selinux_ipv6_forward(unsigned int hooknum, 4515 struct sk_buff *skb, 4516 const struct net_device *in, 4517 const struct net_device *out, 4518 int (*okfn)(struct sk_buff *)) 4519{ 4520 return selinux_ip_forward(skb, in->ifindex, PF_INET6); 4521} 4522#endif /* IPV6 */ 4523 4524static unsigned int selinux_ip_output(struct sk_buff *skb, 4525 u16 family) 4526{ 4527 u32 sid; 4528 4529 if (!netlbl_enabled()) 4530 return NF_ACCEPT; 4531 4532 /* we do this in the LOCAL_OUT path and not the POST_ROUTING path 4533 * because we want to make sure we apply the necessary labeling 4534 * before IPsec is applied so we can leverage AH protection */ 4535 if (skb->sk) { 4536 struct sk_security_struct *sksec = skb->sk->sk_security; 4537 sid = sksec->sid; 4538 } else 4539 sid = SECINITSID_KERNEL; 4540 if (selinux_netlbl_skbuff_setsid(skb, family, sid) != 0) 4541 return NF_DROP; 4542 4543 return NF_ACCEPT; 4544} 4545 4546static unsigned int selinux_ipv4_output(unsigned int hooknum, 4547 struct sk_buff *skb, 4548 const struct net_device *in, 4549 const struct net_device *out, 4550 int (*okfn)(struct sk_buff *)) 4551{ 4552 return selinux_ip_output(skb, PF_INET); 4553} 4554 4555static unsigned int selinux_ip_postroute_compat(struct sk_buff *skb, 4556 int ifindex, 4557 u16 family) 4558{ 4559 struct sock *sk = skb->sk; 4560 struct sk_security_struct *sksec; 4561 struct common_audit_data ad; 4562 char *addrp; 4563 u8 proto; 4564 4565 if (sk == NULL) 4566 return NF_ACCEPT; 4567 sksec = sk->sk_security; 4568 4569 COMMON_AUDIT_DATA_INIT(&ad, NET); 4570 ad.u.net.netif = ifindex; 4571 ad.u.net.family = family; 4572 if (selinux_parse_skb(skb, &ad, &addrp, 0, &proto)) 4573 return NF_DROP; 4574 4575 if (selinux_secmark_enabled()) 4576 if (avc_has_perm(sksec->sid, skb->secmark, 4577 SECCLASS_PACKET, PACKET__SEND, &ad)) 4578 return NF_DROP_ERR(-ECONNREFUSED); 4579 4580 if (selinux_xfrm_postroute_last(sksec->sid, skb, &ad, proto)) 4581 return NF_DROP_ERR(-ECONNREFUSED); 4582 4583 return NF_ACCEPT; 4584} 4585 4586static unsigned int selinux_ip_postroute(struct sk_buff *skb, int ifindex, 4587 u16 family) 4588{ 4589 u32 secmark_perm; 4590 u32 peer_sid; 4591 struct sock *sk; 4592 struct common_audit_data ad; 4593 char *addrp; 4594 u8 secmark_active; 4595 u8 peerlbl_active; 4596 4597 /* If any sort of compatibility mode is enabled then handoff processing 4598 * to the selinux_ip_postroute_compat() function to deal with the 4599 * special handling. We do this in an attempt to keep this function 4600 * as fast and as clean as possible. */ 4601 if (!selinux_policycap_netpeer) 4602 return selinux_ip_postroute_compat(skb, ifindex, family); 4603#ifdef CONFIG_XFRM 4604 /* If skb->dst->xfrm is non-NULL then the packet is undergoing an IPsec 4605 * packet transformation so allow the packet to pass without any checks 4606 * since we'll have another chance to perform access control checks 4607 * when the packet is on it's final way out. 4608 * NOTE: there appear to be some IPv6 multicast cases where skb->dst 4609 * is NULL, in this case go ahead and apply access control. */ 4610 if (skb_dst(skb) != NULL && skb_dst(skb)->xfrm != NULL) 4611 return NF_ACCEPT; 4612#endif 4613 secmark_active = selinux_secmark_enabled(); 4614 peerlbl_active = netlbl_enabled() || selinux_xfrm_enabled(); 4615 if (!secmark_active && !peerlbl_active) 4616 return NF_ACCEPT; 4617 4618 /* if the packet is being forwarded then get the peer label from the 4619 * packet itself; otherwise check to see if it is from a local 4620 * application or the kernel, if from an application get the peer label 4621 * from the sending socket, otherwise use the kernel's sid */ 4622 sk = skb->sk; 4623 if (sk == NULL) { 4624 if (skb->skb_iif) { 4625 secmark_perm = PACKET__FORWARD_OUT; 4626 if (selinux_skb_peerlbl_sid(skb, family, &peer_sid)) 4627 return NF_DROP; 4628 } else { 4629 secmark_perm = PACKET__SEND; 4630 peer_sid = SECINITSID_KERNEL; 4631 } 4632 } else { 4633 struct sk_security_struct *sksec = sk->sk_security; 4634 peer_sid = sksec->sid; 4635 secmark_perm = PACKET__SEND; 4636 } 4637 4638 COMMON_AUDIT_DATA_INIT(&ad, NET); 4639 ad.u.net.netif = ifindex; 4640 ad.u.net.family = family; 4641 if (selinux_parse_skb(skb, &ad, &addrp, 0, NULL)) 4642 return NF_DROP; 4643 4644 if (secmark_active) 4645 if (avc_has_perm(peer_sid, skb->secmark, 4646 SECCLASS_PACKET, secmark_perm, &ad)) 4647 return NF_DROP_ERR(-ECONNREFUSED); 4648 4649 if (peerlbl_active) { 4650 u32 if_sid; 4651 u32 node_sid; 4652 4653 if (sel_netif_sid(ifindex, &if_sid)) 4654 return NF_DROP; 4655 if (avc_has_perm(peer_sid, if_sid, 4656 SECCLASS_NETIF, NETIF__EGRESS, &ad)) 4657 return NF_DROP_ERR(-ECONNREFUSED); 4658 4659 if (sel_netnode_sid(addrp, family, &node_sid)) 4660 return NF_DROP; 4661 if (avc_has_perm(peer_sid, node_sid, 4662 SECCLASS_NODE, NODE__SENDTO, &ad)) 4663 return NF_DROP_ERR(-ECONNREFUSED); 4664 } 4665 4666 return NF_ACCEPT; 4667} 4668 4669static unsigned int selinux_ipv4_postroute(unsigned int hooknum, 4670 struct sk_buff *skb, 4671 const struct net_device *in, 4672 const struct net_device *out, 4673 int (*okfn)(struct sk_buff *)) 4674{ 4675 return selinux_ip_postroute(skb, out->ifindex, PF_INET); 4676} 4677 4678#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE) 4679static unsigned int selinux_ipv6_postroute(unsigned int hooknum, 4680 struct sk_buff *skb, 4681 const struct net_device *in, 4682 const struct net_device *out, 4683 int (*okfn)(struct sk_buff *)) 4684{ 4685 return selinux_ip_postroute(skb, out->ifindex, PF_INET6); 4686} 4687#endif /* IPV6 */ 4688 4689#endif /* CONFIG_NETFILTER */ 4690 4691static int selinux_netlink_send(struct sock *sk, struct sk_buff *skb) 4692{ 4693 int err; 4694 4695 err = cap_netlink_send(sk, skb); 4696 if (err) 4697 return err; 4698 4699 return selinux_nlmsg_perm(sk, skb); 4700} 4701 4702static int selinux_netlink_recv(struct sk_buff *skb, int capability) 4703{ 4704 int err; 4705 struct common_audit_data ad; 4706 u32 sid; 4707 4708 err = cap_netlink_recv(skb, capability); 4709 if (err) 4710 return err; 4711 4712 COMMON_AUDIT_DATA_INIT(&ad, CAP); 4713 ad.u.cap = capability; 4714 4715 security_task_getsecid(current, &sid); 4716 return avc_has_perm(sid, sid, SECCLASS_CAPABILITY, 4717 CAP_TO_MASK(capability), &ad); 4718} 4719 4720static int ipc_alloc_security(struct task_struct *task, 4721 struct kern_ipc_perm *perm, 4722 u16 sclass) 4723{ 4724 struct ipc_security_struct *isec; 4725 u32 sid; 4726 4727 isec = kzalloc(sizeof(struct ipc_security_struct), GFP_KERNEL); 4728 if (!isec) 4729 return -ENOMEM; 4730 4731 sid = task_sid(task); 4732 isec->sclass = sclass; 4733 isec->sid = sid; 4734 perm->security = isec; 4735 4736 return 0; 4737} 4738 4739static void ipc_free_security(struct kern_ipc_perm *perm) 4740{ 4741 struct ipc_security_struct *isec = perm->security; 4742 perm->security = NULL; 4743 kfree(isec); 4744} 4745 4746static int msg_msg_alloc_security(struct msg_msg *msg) 4747{ 4748 struct msg_security_struct *msec; 4749 4750 msec = kzalloc(sizeof(struct msg_security_struct), GFP_KERNEL); 4751 if (!msec) 4752 return -ENOMEM; 4753 4754 msec->sid = SECINITSID_UNLABELED; 4755 msg->security = msec; 4756 4757 return 0; 4758} 4759 4760static void msg_msg_free_security(struct msg_msg *msg) 4761{ 4762 struct msg_security_struct *msec = msg->security; 4763 4764 msg->security = NULL; 4765 kfree(msec); 4766} 4767 4768static int ipc_has_perm(struct kern_ipc_perm *ipc_perms, 4769 u32 perms) 4770{ 4771 struct ipc_security_struct *isec; 4772 struct common_audit_data ad; 4773 u32 sid = current_sid(); 4774 4775 isec = ipc_perms->security; 4776 4777 COMMON_AUDIT_DATA_INIT(&ad, IPC); 4778 ad.u.ipc_id = ipc_perms->key; 4779 4780 return avc_has_perm(sid, isec->sid, isec->sclass, perms, &ad); 4781} 4782 4783static int selinux_msg_msg_alloc_security(struct msg_msg *msg) 4784{ 4785 return msg_msg_alloc_security(msg); 4786} 4787 4788static void selinux_msg_msg_free_security(struct msg_msg *msg) 4789{ 4790 msg_msg_free_security(msg); 4791} 4792 4793/* message queue security operations */ 4794static int selinux_msg_queue_alloc_security(struct msg_queue *msq) 4795{ 4796 struct ipc_security_struct *isec; 4797 struct common_audit_data ad; 4798 u32 sid = current_sid(); 4799 int rc; 4800 4801 rc = ipc_alloc_security(current, &msq->q_perm, SECCLASS_MSGQ); 4802 if (rc) 4803 return rc; 4804 4805 isec = msq->q_perm.security; 4806 4807 COMMON_AUDIT_DATA_INIT(&ad, IPC); 4808 ad.u.ipc_id = msq->q_perm.key; 4809 4810 rc = avc_has_perm(sid, isec->sid, SECCLASS_MSGQ, 4811 MSGQ__CREATE, &ad); 4812 if (rc) { 4813 ipc_free_security(&msq->q_perm); 4814 return rc; 4815 } 4816 return 0; 4817} 4818 4819static void selinux_msg_queue_free_security(struct msg_queue *msq) 4820{ 4821 ipc_free_security(&msq->q_perm); 4822} 4823 4824static int selinux_msg_queue_associate(struct msg_queue *msq, int msqflg) 4825{ 4826 struct ipc_security_struct *isec; 4827 struct common_audit_data ad; 4828 u32 sid = current_sid(); 4829 4830 isec = msq->q_perm.security; 4831 4832 COMMON_AUDIT_DATA_INIT(&ad, IPC); 4833 ad.u.ipc_id = msq->q_perm.key; 4834 4835 return avc_has_perm(sid, isec->sid, SECCLASS_MSGQ, 4836 MSGQ__ASSOCIATE, &ad); 4837} 4838 4839static int selinux_msg_queue_msgctl(struct msg_queue *msq, int cmd) 4840{ 4841 int err; 4842 int perms; 4843 4844 switch (cmd) { 4845 case IPC_INFO: 4846 case MSG_INFO: 4847 /* No specific object, just general system-wide information. */ 4848 return task_has_system(current, SYSTEM__IPC_INFO); 4849 case IPC_STAT: 4850 case MSG_STAT: 4851 perms = MSGQ__GETATTR | MSGQ__ASSOCIATE; 4852 break; 4853 case IPC_SET: 4854 perms = MSGQ__SETATTR; 4855 break; 4856 case IPC_RMID: 4857 perms = MSGQ__DESTROY; 4858 break; 4859 default: 4860 return 0; 4861 } 4862 4863 err = ipc_has_perm(&msq->q_perm, perms); 4864 return err; 4865} 4866 4867static int selinux_msg_queue_msgsnd(struct msg_queue *msq, struct msg_msg *msg, int msqflg) 4868{ 4869 struct ipc_security_struct *isec; 4870 struct msg_security_struct *msec; 4871 struct common_audit_data ad; 4872 u32 sid = current_sid(); 4873 int rc; 4874 4875 isec = msq->q_perm.security; 4876 msec = msg->security; 4877 4878 /* 4879 * First time through, need to assign label to the message 4880 */ 4881 if (msec->sid == SECINITSID_UNLABELED) { 4882 /* 4883 * Compute new sid based on current process and 4884 * message queue this message will be stored in 4885 */ 4886 rc = security_transition_sid(sid, isec->sid, SECCLASS_MSG, 4887 NULL, &msec->sid); 4888 if (rc) 4889 return rc; 4890 } 4891 4892 COMMON_AUDIT_DATA_INIT(&ad, IPC); 4893 ad.u.ipc_id = msq->q_perm.key; 4894 4895 /* Can this process write to the queue? */ 4896 rc = avc_has_perm(sid, isec->sid, SECCLASS_MSGQ, 4897 MSGQ__WRITE, &ad); 4898 if (!rc) 4899 /* Can this process send the message */ 4900 rc = avc_has_perm(sid, msec->sid, SECCLASS_MSG, 4901 MSG__SEND, &ad); 4902 if (!rc) 4903 /* Can the message be put in the queue? */ 4904 rc = avc_has_perm(msec->sid, isec->sid, SECCLASS_MSGQ, 4905 MSGQ__ENQUEUE, &ad); 4906 4907 return rc; 4908} 4909 4910static int selinux_msg_queue_msgrcv(struct msg_queue *msq, struct msg_msg *msg, 4911 struct task_struct *target, 4912 long type, int mode) 4913{ 4914 struct ipc_security_struct *isec; 4915 struct msg_security_struct *msec; 4916 struct common_audit_data ad; 4917 u32 sid = task_sid(target); 4918 int rc; 4919 4920 isec = msq->q_perm.security; 4921 msec = msg->security; 4922 4923 COMMON_AUDIT_DATA_INIT(&ad, IPC); 4924 ad.u.ipc_id = msq->q_perm.key; 4925 4926 rc = avc_has_perm(sid, isec->sid, 4927 SECCLASS_MSGQ, MSGQ__READ, &ad); 4928 if (!rc) 4929 rc = avc_has_perm(sid, msec->sid, 4930 SECCLASS_MSG, MSG__RECEIVE, &ad); 4931 return rc; 4932} 4933 4934/* Shared Memory security operations */ 4935static int selinux_shm_alloc_security(struct shmid_kernel *shp) 4936{ 4937 struct ipc_security_struct *isec; 4938 struct common_audit_data ad; 4939 u32 sid = current_sid(); 4940 int rc; 4941 4942 rc = ipc_alloc_security(current, &shp->shm_perm, SECCLASS_SHM); 4943 if (rc) 4944 return rc; 4945 4946 isec = shp->shm_perm.security; 4947 4948 COMMON_AUDIT_DATA_INIT(&ad, IPC); 4949 ad.u.ipc_id = shp->shm_perm.key; 4950 4951 rc = avc_has_perm(sid, isec->sid, SECCLASS_SHM, 4952 SHM__CREATE, &ad); 4953 if (rc) { 4954 ipc_free_security(&shp->shm_perm); 4955 return rc; 4956 } 4957 return 0; 4958} 4959 4960static void selinux_shm_free_security(struct shmid_kernel *shp) 4961{ 4962 ipc_free_security(&shp->shm_perm); 4963} 4964 4965static int selinux_shm_associate(struct shmid_kernel *shp, int shmflg) 4966{ 4967 struct ipc_security_struct *isec; 4968 struct common_audit_data ad; 4969 u32 sid = current_sid(); 4970 4971 isec = shp->shm_perm.security; 4972 4973 COMMON_AUDIT_DATA_INIT(&ad, IPC); 4974 ad.u.ipc_id = shp->shm_perm.key; 4975 4976 return avc_has_perm(sid, isec->sid, SECCLASS_SHM, 4977 SHM__ASSOCIATE, &ad); 4978} 4979 4980/* Note, at this point, shp is locked down */ 4981static int selinux_shm_shmctl(struct shmid_kernel *shp, int cmd) 4982{ 4983 int perms; 4984 int err; 4985 4986 switch (cmd) { 4987 case IPC_INFO: 4988 case SHM_INFO: 4989 /* No specific object, just general system-wide information. */ 4990 return task_has_system(current, SYSTEM__IPC_INFO); 4991 case IPC_STAT: 4992 case SHM_STAT: 4993 perms = SHM__GETATTR | SHM__ASSOCIATE; 4994 break; 4995 case IPC_SET: 4996 perms = SHM__SETATTR; 4997 break; 4998 case SHM_LOCK: 4999 case SHM_UNLOCK: 5000 perms = SHM__LOCK; 5001 break; 5002 case IPC_RMID: 5003 perms = SHM__DESTROY; 5004 break; 5005 default: 5006 return 0; 5007 } 5008 5009 err = ipc_has_perm(&shp->shm_perm, perms); 5010 return err; 5011} 5012 5013static int selinux_shm_shmat(struct shmid_kernel *shp, 5014 char __user *shmaddr, int shmflg) 5015{ 5016 u32 perms; 5017 5018 if (shmflg & SHM_RDONLY) 5019 perms = SHM__READ; 5020 else 5021 perms = SHM__READ | SHM__WRITE; 5022 5023 return ipc_has_perm(&shp->shm_perm, perms); 5024} 5025 5026/* Semaphore security operations */ 5027static int selinux_sem_alloc_security(struct sem_array *sma) 5028{ 5029 struct ipc_security_struct *isec; 5030 struct common_audit_data ad; 5031 u32 sid = current_sid(); 5032 int rc; 5033 5034 rc = ipc_alloc_security(current, &sma->sem_perm, SECCLASS_SEM); 5035 if (rc) 5036 return rc; 5037 5038 isec = sma->sem_perm.security; 5039 5040 COMMON_AUDIT_DATA_INIT(&ad, IPC); 5041 ad.u.ipc_id = sma->sem_perm.key; 5042 5043 rc = avc_has_perm(sid, isec->sid, SECCLASS_SEM, 5044 SEM__CREATE, &ad); 5045 if (rc) { 5046 ipc_free_security(&sma->sem_perm); 5047 return rc; 5048 } 5049 return 0; 5050} 5051 5052static void selinux_sem_free_security(struct sem_array *sma) 5053{ 5054 ipc_free_security(&sma->sem_perm); 5055} 5056 5057static int selinux_sem_associate(struct sem_array *sma, int semflg) 5058{ 5059 struct ipc_security_struct *isec; 5060 struct common_audit_data ad; 5061 u32 sid = current_sid(); 5062 5063 isec = sma->sem_perm.security; 5064 5065 COMMON_AUDIT_DATA_INIT(&ad, IPC); 5066 ad.u.ipc_id = sma->sem_perm.key; 5067 5068 return avc_has_perm(sid, isec->sid, SECCLASS_SEM, 5069 SEM__ASSOCIATE, &ad); 5070} 5071 5072/* Note, at this point, sma is locked down */ 5073static int selinux_sem_semctl(struct sem_array *sma, int cmd) 5074{ 5075 int err; 5076 u32 perms; 5077 5078 switch (cmd) { 5079 case IPC_INFO: 5080 case SEM_INFO: 5081 /* No specific object, just general system-wide information. */ 5082 return task_has_system(current, SYSTEM__IPC_INFO); 5083 case GETPID: 5084 case GETNCNT: 5085 case GETZCNT: 5086 perms = SEM__GETATTR; 5087 break; 5088 case GETVAL: 5089 case GETALL: 5090 perms = SEM__READ; 5091 break; 5092 case SETVAL: 5093 case SETALL: 5094 perms = SEM__WRITE; 5095 break; 5096 case IPC_RMID: 5097 perms = SEM__DESTROY; 5098 break; 5099 case IPC_SET: 5100 perms = SEM__SETATTR; 5101 break; 5102 case IPC_STAT: 5103 case SEM_STAT: 5104 perms = SEM__GETATTR | SEM__ASSOCIATE; 5105 break; 5106 default: 5107 return 0; 5108 } 5109 5110 err = ipc_has_perm(&sma->sem_perm, perms); 5111 return err; 5112} 5113 5114static int selinux_sem_semop(struct sem_array *sma, 5115 struct sembuf *sops, unsigned nsops, int alter) 5116{ 5117 u32 perms; 5118 5119 if (alter) 5120 perms = SEM__READ | SEM__WRITE; 5121 else 5122 perms = SEM__READ; 5123 5124 return ipc_has_perm(&sma->sem_perm, perms); 5125} 5126 5127static int selinux_ipc_permission(struct kern_ipc_perm *ipcp, short flag) 5128{ 5129 u32 av = 0; 5130 5131 av = 0; 5132 if (flag & S_IRUGO) 5133 av |= IPC__UNIX_READ; 5134 if (flag & S_IWUGO) 5135 av |= IPC__UNIX_WRITE; 5136 5137 if (av == 0) 5138 return 0; 5139 5140 return ipc_has_perm(ipcp, av); 5141} 5142 5143static void selinux_ipc_getsecid(struct kern_ipc_perm *ipcp, u32 *secid) 5144{ 5145 struct ipc_security_struct *isec = ipcp->security; 5146 *secid = isec->sid; 5147} 5148 5149static void selinux_d_instantiate(struct dentry *dentry, struct inode *inode) 5150{ 5151 if (inode) 5152 inode_doinit_with_dentry(inode, dentry); 5153} 5154 5155static int selinux_getprocattr(struct task_struct *p, 5156 char *name, char **value) 5157{ 5158 const struct task_security_struct *__tsec; 5159 u32 sid; 5160 int error; 5161 unsigned len; 5162 5163 if (current != p) { 5164 error = current_has_perm(p, PROCESS__GETATTR); 5165 if (error) 5166 return error; 5167 } 5168 5169 rcu_read_lock(); 5170 __tsec = __task_cred(p)->security; 5171 5172 if (!strcmp(name, "current")) 5173 sid = __tsec->sid; 5174 else if (!strcmp(name, "prev")) 5175 sid = __tsec->osid; 5176 else if (!strcmp(name, "exec")) 5177 sid = __tsec->exec_sid; 5178 else if (!strcmp(name, "fscreate")) 5179 sid = __tsec->create_sid; 5180 else if (!strcmp(name, "keycreate")) 5181 sid = __tsec->keycreate_sid; 5182 else if (!strcmp(name, "sockcreate")) 5183 sid = __tsec->sockcreate_sid; 5184 else 5185 goto invalid; 5186 rcu_read_unlock(); 5187 5188 if (!sid) 5189 return 0; 5190 5191 error = security_sid_to_context(sid, value, &len); 5192 if (error) 5193 return error; 5194 return len; 5195 5196invalid: 5197 rcu_read_unlock(); 5198 return -EINVAL; 5199} 5200 5201static int selinux_setprocattr(struct task_struct *p, 5202 char *name, void *value, size_t size) 5203{ 5204 struct task_security_struct *tsec; 5205 struct task_struct *tracer; 5206 struct cred *new; 5207 u32 sid = 0, ptsid; 5208 int error; 5209 char *str = value; 5210 5211 if (current != p) { 5212 /* SELinux only allows a process to change its own 5213 security attributes. */ 5214 return -EACCES; 5215 } 5216 5217 /* 5218 * Basic control over ability to set these attributes at all. 5219 * current == p, but we'll pass them separately in case the 5220 * above restriction is ever removed. 5221 */ 5222 if (!strcmp(name, "exec")) 5223 error = current_has_perm(p, PROCESS__SETEXEC); 5224 else if (!strcmp(name, "fscreate")) 5225 error = current_has_perm(p, PROCESS__SETFSCREATE); 5226 else if (!strcmp(name, "keycreate")) 5227 error = current_has_perm(p, PROCESS__SETKEYCREATE); 5228 else if (!strcmp(name, "sockcreate")) 5229 error = current_has_perm(p, PROCESS__SETSOCKCREATE); 5230 else if (!strcmp(name, "current")) 5231 error = current_has_perm(p, PROCESS__SETCURRENT); 5232 else 5233 error = -EINVAL; 5234 if (error) 5235 return error; 5236 5237 /* Obtain a SID for the context, if one was specified. */ 5238 if (size && str[1] && str[1] != '\n') { 5239 if (str[size-1] == '\n') { 5240 str[size-1] = 0; 5241 size--; 5242 } 5243 error = security_context_to_sid(value, size, &sid); 5244 if (error == -EINVAL && !strcmp(name, "fscreate")) { 5245 if (!capable(CAP_MAC_ADMIN)) 5246 return error; 5247 error = security_context_to_sid_force(value, size, 5248 &sid); 5249 } 5250 if (error) 5251 return error; 5252 } 5253 5254 new = prepare_creds(); 5255 if (!new) 5256 return -ENOMEM; 5257 5258 /* Permission checking based on the specified context is 5259 performed during the actual operation (execve, 5260 open/mkdir/...), when we know the full context of the 5261 operation. See selinux_bprm_set_creds for the execve 5262 checks and may_create for the file creation checks. The 5263 operation will then fail if the context is not permitted. */ 5264 tsec = new->security; 5265 if (!strcmp(name, "exec")) { 5266 tsec->exec_sid = sid; 5267 } else if (!strcmp(name, "fscreate")) { 5268 tsec->create_sid = sid; 5269 } else if (!strcmp(name, "keycreate")) { 5270 error = may_create_key(sid, p); 5271 if (error) 5272 goto abort_change; 5273 tsec->keycreate_sid = sid; 5274 } else if (!strcmp(name, "sockcreate")) { 5275 tsec->sockcreate_sid = sid; 5276 } else if (!strcmp(name, "current")) { 5277 error = -EINVAL; 5278 if (sid == 0) 5279 goto abort_change; 5280 5281 /* Only allow single threaded processes to change context */ 5282 error = -EPERM; 5283 if (!current_is_single_threaded()) { 5284 error = security_bounded_transition(tsec->sid, sid); 5285 if (error) 5286 goto abort_change; 5287 } 5288 5289 /* Check permissions for the transition. */ 5290 error = avc_has_perm(tsec->sid, sid, SECCLASS_PROCESS, 5291 PROCESS__DYNTRANSITION, NULL); 5292 if (error) 5293 goto abort_change; 5294 5295 /* Check for ptracing, and update the task SID if ok. 5296 Otherwise, leave SID unchanged and fail. */ 5297 ptsid = 0; 5298 task_lock(p); 5299 tracer = tracehook_tracer_task(p); 5300 if (tracer) 5301 ptsid = task_sid(tracer); 5302 task_unlock(p); 5303 5304 if (tracer) { 5305 error = avc_has_perm(ptsid, sid, SECCLASS_PROCESS, 5306 PROCESS__PTRACE, NULL); 5307 if (error) 5308 goto abort_change; 5309 } 5310 5311 tsec->sid = sid; 5312 } else { 5313 error = -EINVAL; 5314 goto abort_change; 5315 } 5316 5317 commit_creds(new); 5318 return size; 5319 5320abort_change: 5321 abort_creds(new); 5322 return error; 5323} 5324 5325static int selinux_secid_to_secctx(u32 secid, char **secdata, u32 *seclen) 5326{ 5327 return security_sid_to_context(secid, secdata, seclen); 5328} 5329 5330static int selinux_secctx_to_secid(const char *secdata, u32 seclen, u32 *secid) 5331{ 5332 return security_context_to_sid(secdata, seclen, secid); 5333} 5334 5335static void selinux_release_secctx(char *secdata, u32 seclen) 5336{ 5337 kfree(secdata); 5338} 5339 5340/* 5341 * called with inode->i_mutex locked 5342 */ 5343static int selinux_inode_notifysecctx(struct inode *inode, void *ctx, u32 ctxlen) 5344{ 5345 return selinux_inode_setsecurity(inode, XATTR_SELINUX_SUFFIX, ctx, ctxlen, 0); 5346} 5347 5348/* 5349 * called with inode->i_mutex locked 5350 */ 5351static int selinux_inode_setsecctx(struct dentry *dentry, void *ctx, u32 ctxlen) 5352{ 5353 return __vfs_setxattr_noperm(dentry, XATTR_NAME_SELINUX, ctx, ctxlen, 0); 5354} 5355 5356static int selinux_inode_getsecctx(struct inode *inode, void **ctx, u32 *ctxlen) 5357{ 5358 int len = 0; 5359 len = selinux_inode_getsecurity(inode, XATTR_SELINUX_SUFFIX, 5360 ctx, true); 5361 if (len < 0) 5362 return len; 5363 *ctxlen = len; 5364 return 0; 5365} 5366#ifdef CONFIG_KEYS 5367 5368static int selinux_key_alloc(struct key *k, const struct cred *cred, 5369 unsigned long flags) 5370{ 5371 const struct task_security_struct *tsec; 5372 struct key_security_struct *ksec; 5373 5374 ksec = kzalloc(sizeof(struct key_security_struct), GFP_KERNEL); 5375 if (!ksec) 5376 return -ENOMEM; 5377 5378 tsec = cred->security; 5379 if (tsec->keycreate_sid) 5380 ksec->sid = tsec->keycreate_sid; 5381 else 5382 ksec->sid = tsec->sid; 5383 5384 k->security = ksec; 5385 return 0; 5386} 5387 5388static void selinux_key_free(struct key *k) 5389{ 5390 struct key_security_struct *ksec = k->security; 5391 5392 k->security = NULL; 5393 kfree(ksec); 5394} 5395 5396static int selinux_key_permission(key_ref_t key_ref, 5397 const struct cred *cred, 5398 key_perm_t perm) 5399{ 5400 struct key *key; 5401 struct key_security_struct *ksec; 5402 u32 sid; 5403 5404 /* if no specific permissions are requested, we skip the 5405 permission check. No serious, additional covert channels 5406 appear to be created. */ 5407 if (perm == 0) 5408 return 0; 5409 5410 sid = cred_sid(cred); 5411 5412 key = key_ref_to_ptr(key_ref); 5413 ksec = key->security; 5414 5415 return avc_has_perm(sid, ksec->sid, SECCLASS_KEY, perm, NULL); 5416} 5417 5418static int selinux_key_getsecurity(struct key *key, char **_buffer) 5419{ 5420 struct key_security_struct *ksec = key->security; 5421 char *context = NULL; 5422 unsigned len; 5423 int rc; 5424 5425 rc = security_sid_to_context(ksec->sid, &context, &len); 5426 if (!rc) 5427 rc = len; 5428 *_buffer = context; 5429 return rc; 5430} 5431 5432#endif 5433 5434static struct security_operations selinux_ops = { 5435 .name = "selinux", 5436 5437 .ptrace_access_check = selinux_ptrace_access_check, 5438 .ptrace_traceme = selinux_ptrace_traceme, 5439 .capget = selinux_capget, 5440 .capset = selinux_capset, 5441 .capable = selinux_capable, 5442 .quotactl = selinux_quotactl, 5443 .quota_on = selinux_quota_on, 5444 .syslog = selinux_syslog, 5445 .vm_enough_memory = selinux_vm_enough_memory, 5446 5447 .netlink_send = selinux_netlink_send, 5448 .netlink_recv = selinux_netlink_recv, 5449 5450 .bprm_set_creds = selinux_bprm_set_creds, 5451 .bprm_committing_creds = selinux_bprm_committing_creds, 5452 .bprm_committed_creds = selinux_bprm_committed_creds, 5453 .bprm_secureexec = selinux_bprm_secureexec, 5454 5455 .sb_alloc_security = selinux_sb_alloc_security, 5456 .sb_free_security = selinux_sb_free_security, 5457 .sb_copy_data = selinux_sb_copy_data, 5458 .sb_remount = selinux_sb_remount, 5459 .sb_kern_mount = selinux_sb_kern_mount, 5460 .sb_show_options = selinux_sb_show_options, 5461 .sb_statfs = selinux_sb_statfs, 5462 .sb_mount = selinux_mount, 5463 .sb_umount = selinux_umount, 5464 .sb_set_mnt_opts = selinux_set_mnt_opts, 5465 .sb_clone_mnt_opts = selinux_sb_clone_mnt_opts, 5466 .sb_parse_opts_str = selinux_parse_opts_str, 5467 5468 5469 .inode_alloc_security = selinux_inode_alloc_security, 5470 .inode_free_security = selinux_inode_free_security, 5471 .inode_init_security = selinux_inode_init_security, 5472 .inode_create = selinux_inode_create, 5473 .inode_link = selinux_inode_link, 5474 .inode_unlink = selinux_inode_unlink, 5475 .inode_symlink = selinux_inode_symlink, 5476 .inode_mkdir = selinux_inode_mkdir, 5477 .inode_rmdir = selinux_inode_rmdir, 5478 .inode_mknod = selinux_inode_mknod, 5479 .inode_rename = selinux_inode_rename, 5480 .inode_readlink = selinux_inode_readlink, 5481 .inode_follow_link = selinux_inode_follow_link, 5482 .inode_permission = selinux_inode_permission, 5483 .inode_setattr = selinux_inode_setattr, 5484 .inode_getattr = selinux_inode_getattr, 5485 .inode_setxattr = selinux_inode_setxattr, 5486 .inode_post_setxattr = selinux_inode_post_setxattr, 5487 .inode_getxattr = selinux_inode_getxattr, 5488 .inode_listxattr = selinux_inode_listxattr, 5489 .inode_removexattr = selinux_inode_removexattr, 5490 .inode_getsecurity = selinux_inode_getsecurity, 5491 .inode_setsecurity = selinux_inode_setsecurity, 5492 .inode_listsecurity = selinux_inode_listsecurity, 5493 .inode_getsecid = selinux_inode_getsecid, 5494 5495 .file_permission = selinux_file_permission, 5496 .file_alloc_security = selinux_file_alloc_security, 5497 .file_free_security = selinux_file_free_security, 5498 .file_ioctl = selinux_file_ioctl, 5499 .file_mmap = selinux_file_mmap, 5500 .file_mprotect = selinux_file_mprotect, 5501 .file_lock = selinux_file_lock, 5502 .file_fcntl = selinux_file_fcntl, 5503 .file_set_fowner = selinux_file_set_fowner, 5504 .file_send_sigiotask = selinux_file_send_sigiotask, 5505 .file_receive = selinux_file_receive, 5506 5507 .dentry_open = selinux_dentry_open, 5508 5509 .task_create = selinux_task_create, 5510 .cred_alloc_blank = selinux_cred_alloc_blank, 5511 .cred_free = selinux_cred_free, 5512 .cred_prepare = selinux_cred_prepare, 5513 .cred_transfer = selinux_cred_transfer, 5514 .kernel_act_as = selinux_kernel_act_as, 5515 .kernel_create_files_as = selinux_kernel_create_files_as, 5516 .kernel_module_request = selinux_kernel_module_request, 5517 .task_setpgid = selinux_task_setpgid, 5518 .task_getpgid = selinux_task_getpgid, 5519 .task_getsid = selinux_task_getsid, 5520 .task_getsecid = selinux_task_getsecid, 5521 .task_setnice = selinux_task_setnice, 5522 .task_setioprio = selinux_task_setioprio, 5523 .task_getioprio = selinux_task_getioprio, 5524 .task_setrlimit = selinux_task_setrlimit, 5525 .task_setscheduler = selinux_task_setscheduler, 5526 .task_getscheduler = selinux_task_getscheduler, 5527 .task_movememory = selinux_task_movememory, 5528 .task_kill = selinux_task_kill, 5529 .task_wait = selinux_task_wait, 5530 .task_to_inode = selinux_task_to_inode, 5531 5532 .ipc_permission = selinux_ipc_permission, 5533 .ipc_getsecid = selinux_ipc_getsecid, 5534 5535 .msg_msg_alloc_security = selinux_msg_msg_alloc_security, 5536 .msg_msg_free_security = selinux_msg_msg_free_security, 5537 5538 .msg_queue_alloc_security = selinux_msg_queue_alloc_security, 5539 .msg_queue_free_security = selinux_msg_queue_free_security, 5540 .msg_queue_associate = selinux_msg_queue_associate, 5541 .msg_queue_msgctl = selinux_msg_queue_msgctl, 5542 .msg_queue_msgsnd = selinux_msg_queue_msgsnd, 5543 .msg_queue_msgrcv = selinux_msg_queue_msgrcv, 5544 5545 .shm_alloc_security = selinux_shm_alloc_security, 5546 .shm_free_security = selinux_shm_free_security, 5547 .shm_associate = selinux_shm_associate, 5548 .shm_shmctl = selinux_shm_shmctl, 5549 .shm_shmat = selinux_shm_shmat, 5550 5551 .sem_alloc_security = selinux_sem_alloc_security, 5552 .sem_free_security = selinux_sem_free_security, 5553 .sem_associate = selinux_sem_associate, 5554 .sem_semctl = selinux_sem_semctl, 5555 .sem_semop = selinux_sem_semop, 5556 5557 .d_instantiate = selinux_d_instantiate, 5558 5559 .getprocattr = selinux_getprocattr, 5560 .setprocattr = selinux_setprocattr, 5561 5562 .secid_to_secctx = selinux_secid_to_secctx, 5563 .secctx_to_secid = selinux_secctx_to_secid, 5564 .release_secctx = selinux_release_secctx, 5565 .inode_notifysecctx = selinux_inode_notifysecctx, 5566 .inode_setsecctx = selinux_inode_setsecctx, 5567 .inode_getsecctx = selinux_inode_getsecctx, 5568 5569 .unix_stream_connect = selinux_socket_unix_stream_connect, 5570 .unix_may_send = selinux_socket_unix_may_send, 5571 5572 .socket_create = selinux_socket_create, 5573 .socket_post_create = selinux_socket_post_create, 5574 .socket_bind = selinux_socket_bind, 5575 .socket_connect = selinux_socket_connect, 5576 .socket_listen = selinux_socket_listen, 5577 .socket_accept = selinux_socket_accept, 5578 .socket_sendmsg = selinux_socket_sendmsg, 5579 .socket_recvmsg = selinux_socket_recvmsg, 5580 .socket_getsockname = selinux_socket_getsockname, 5581 .socket_getpeername = selinux_socket_getpeername, 5582 .socket_getsockopt = selinux_socket_getsockopt, 5583 .socket_setsockopt = selinux_socket_setsockopt, 5584 .socket_shutdown = selinux_socket_shutdown, 5585 .socket_sock_rcv_skb = selinux_socket_sock_rcv_skb, 5586 .socket_getpeersec_stream = selinux_socket_getpeersec_stream, 5587 .socket_getpeersec_dgram = selinux_socket_getpeersec_dgram, 5588 .sk_alloc_security = selinux_sk_alloc_security, 5589 .sk_free_security = selinux_sk_free_security, 5590 .sk_clone_security = selinux_sk_clone_security, 5591 .sk_getsecid = selinux_sk_getsecid, 5592 .sock_graft = selinux_sock_graft, 5593 .inet_conn_request = selinux_inet_conn_request, 5594 .inet_csk_clone = selinux_inet_csk_clone, 5595 .inet_conn_established = selinux_inet_conn_established, 5596 .secmark_relabel_packet = selinux_secmark_relabel_packet, 5597 .secmark_refcount_inc = selinux_secmark_refcount_inc, 5598 .secmark_refcount_dec = selinux_secmark_refcount_dec, 5599 .req_classify_flow = selinux_req_classify_flow, 5600 .tun_dev_create = selinux_tun_dev_create, 5601 .tun_dev_post_create = selinux_tun_dev_post_create, 5602 .tun_dev_attach = selinux_tun_dev_attach, 5603 5604#ifdef CONFIG_SECURITY_NETWORK_XFRM 5605 .xfrm_policy_alloc_security = selinux_xfrm_policy_alloc, 5606 .xfrm_policy_clone_security = selinux_xfrm_policy_clone, 5607 .xfrm_policy_free_security = selinux_xfrm_policy_free, 5608 .xfrm_policy_delete_security = selinux_xfrm_policy_delete, 5609 .xfrm_state_alloc_security = selinux_xfrm_state_alloc, 5610 .xfrm_state_free_security = selinux_xfrm_state_free, 5611 .xfrm_state_delete_security = selinux_xfrm_state_delete, 5612 .xfrm_policy_lookup = selinux_xfrm_policy_lookup, 5613 .xfrm_state_pol_flow_match = selinux_xfrm_state_pol_flow_match, 5614 .xfrm_decode_session = selinux_xfrm_decode_session, 5615#endif 5616 5617#ifdef CONFIG_KEYS 5618 .key_alloc = selinux_key_alloc, 5619 .key_free = selinux_key_free, 5620 .key_permission = selinux_key_permission, 5621 .key_getsecurity = selinux_key_getsecurity, 5622#endif 5623 5624#ifdef CONFIG_AUDIT 5625 .audit_rule_init = selinux_audit_rule_init, 5626 .audit_rule_known = selinux_audit_rule_known, 5627 .audit_rule_match = selinux_audit_rule_match, 5628 .audit_rule_free = selinux_audit_rule_free, 5629#endif 5630}; 5631 5632static __init int selinux_init(void) 5633{ 5634 if (!security_module_enable(&selinux_ops)) { 5635 selinux_enabled = 0; 5636 return 0; 5637 } 5638 5639 if (!selinux_enabled) { 5640 printk(KERN_INFO "SELinux: Disabled at boot.\n"); 5641 return 0; 5642 } 5643 5644 printk(KERN_INFO "SELinux: Initializing.\n"); 5645 5646 /* Set the security state for the initial task. */ 5647 cred_init_security(); 5648 5649 default_noexec = !(VM_DATA_DEFAULT_FLAGS & VM_EXEC); 5650 5651 sel_inode_cache = kmem_cache_create("selinux_inode_security", 5652 sizeof(struct inode_security_struct), 5653 0, SLAB_PANIC, NULL); 5654 avc_init(); 5655 5656 if (register_security(&selinux_ops)) 5657 panic("SELinux: Unable to register with kernel.\n"); 5658 5659 if (selinux_enforcing) 5660 printk(KERN_DEBUG "SELinux: Starting in enforcing mode\n"); 5661 else 5662 printk(KERN_DEBUG "SELinux: Starting in permissive mode\n"); 5663 5664 return 0; 5665} 5666 5667static void delayed_superblock_init(struct super_block *sb, void *unused) 5668{ 5669 superblock_doinit(sb, NULL); 5670} 5671 5672void selinux_complete_init(void) 5673{ 5674 printk(KERN_DEBUG "SELinux: Completing initialization.\n"); 5675 5676 /* Set up any superblocks initialized prior to the policy load. */ 5677 printk(KERN_DEBUG "SELinux: Setting up existing superblocks.\n"); 5678 iterate_supers(delayed_superblock_init, NULL); 5679} 5680 5681/* SELinux requires early initialization in order to label 5682 all processes and objects when they are created. */ 5683security_initcall(selinux_init); 5684 5685#if defined(CONFIG_NETFILTER) 5686 5687static struct nf_hook_ops selinux_ipv4_ops[] = { 5688 { 5689 .hook = selinux_ipv4_postroute, 5690 .owner = THIS_MODULE, 5691 .pf = PF_INET, 5692 .hooknum = NF_INET_POST_ROUTING, 5693 .priority = NF_IP_PRI_SELINUX_LAST, 5694 }, 5695 { 5696 .hook = selinux_ipv4_forward, 5697 .owner = THIS_MODULE, 5698 .pf = PF_INET, 5699 .hooknum = NF_INET_FORWARD, 5700 .priority = NF_IP_PRI_SELINUX_FIRST, 5701 }, 5702 { 5703 .hook = selinux_ipv4_output, 5704 .owner = THIS_MODULE, 5705 .pf = PF_INET, 5706 .hooknum = NF_INET_LOCAL_OUT, 5707 .priority = NF_IP_PRI_SELINUX_FIRST, 5708 } 5709}; 5710 5711#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE) 5712 5713static struct nf_hook_ops selinux_ipv6_ops[] = { 5714 { 5715 .hook = selinux_ipv6_postroute, 5716 .owner = THIS_MODULE, 5717 .pf = PF_INET6, 5718 .hooknum = NF_INET_POST_ROUTING, 5719 .priority = NF_IP6_PRI_SELINUX_LAST, 5720 }, 5721 { 5722 .hook = selinux_ipv6_forward, 5723 .owner = THIS_MODULE, 5724 .pf = PF_INET6, 5725 .hooknum = NF_INET_FORWARD, 5726 .priority = NF_IP6_PRI_SELINUX_FIRST, 5727 } 5728}; 5729 5730#endif /* IPV6 */ 5731 5732static int __init selinux_nf_ip_init(void) 5733{ 5734 int err = 0; 5735 5736 if (!selinux_enabled) 5737 goto out; 5738 5739 printk(KERN_DEBUG "SELinux: Registering netfilter hooks\n"); 5740 5741 err = nf_register_hooks(selinux_ipv4_ops, ARRAY_SIZE(selinux_ipv4_ops)); 5742 if (err) 5743 panic("SELinux: nf_register_hooks for IPv4: error %d\n", err); 5744 5745#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE) 5746 err = nf_register_hooks(selinux_ipv6_ops, ARRAY_SIZE(selinux_ipv6_ops)); 5747 if (err) 5748 panic("SELinux: nf_register_hooks for IPv6: error %d\n", err); 5749#endif /* IPV6 */ 5750 5751out: 5752 return err; 5753} 5754 5755__initcall(selinux_nf_ip_init); 5756 5757#ifdef CONFIG_SECURITY_SELINUX_DISABLE 5758static void selinux_nf_ip_exit(void) 5759{ 5760 printk(KERN_DEBUG "SELinux: Unregistering netfilter hooks\n"); 5761 5762 nf_unregister_hooks(selinux_ipv4_ops, ARRAY_SIZE(selinux_ipv4_ops)); 5763#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE) 5764 nf_unregister_hooks(selinux_ipv6_ops, ARRAY_SIZE(selinux_ipv6_ops)); 5765#endif /* IPV6 */ 5766} 5767#endif 5768 5769#else /* CONFIG_NETFILTER */ 5770 5771#ifdef CONFIG_SECURITY_SELINUX_DISABLE 5772#define selinux_nf_ip_exit() 5773#endif 5774 5775#endif /* CONFIG_NETFILTER */ 5776 5777#ifdef CONFIG_SECURITY_SELINUX_DISABLE 5778static int selinux_disabled; 5779 5780int selinux_disable(void) 5781{ 5782 extern void exit_sel_fs(void); 5783 5784 if (ss_initialized) { 5785 /* Not permitted after initial policy load. */ 5786 return -EINVAL; 5787 } 5788 5789 if (selinux_disabled) { 5790 /* Only do this once. */ 5791 return -EINVAL; 5792 } 5793 5794 printk(KERN_INFO "SELinux: Disabled at runtime.\n"); 5795 5796 selinux_disabled = 1; 5797 selinux_enabled = 0; 5798 5799 reset_security_ops(); 5800 5801 /* Try to destroy the avc node cache */ 5802 avc_disable(); 5803 5804 /* Unregister netfilter hooks. */ 5805 selinux_nf_ip_exit(); 5806 5807 /* Unregister selinuxfs. */ 5808 exit_sel_fs(); 5809 5810 return 0; 5811} 5812#endif