at v3.14 6127 lines 154 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@paul-moore.com> 18 * Copyright (C) 2007 Hitachi Software Engineering Co., Ltd. 19 * Yuichi Nakamura <ynakam@hitachisoft.jp> 20 * 21 * This program is free software; you can redistribute it and/or modify 22 * it under the terms of the GNU General Public License version 2, 23 * as published by the Free Software Foundation. 24 */ 25 26#include <linux/init.h> 27#include <linux/kd.h> 28#include <linux/kernel.h> 29#include <linux/tracehook.h> 30#include <linux/errno.h> 31#include <linux/sched.h> 32#include <linux/security.h> 33#include <linux/xattr.h> 34#include <linux/capability.h> 35#include <linux/unistd.h> 36#include <linux/mm.h> 37#include <linux/mman.h> 38#include <linux/slab.h> 39#include <linux/pagemap.h> 40#include <linux/proc_fs.h> 41#include <linux/swap.h> 42#include <linux/spinlock.h> 43#include <linux/syscalls.h> 44#include <linux/dcache.h> 45#include <linux/file.h> 46#include <linux/fdtable.h> 47#include <linux/namei.h> 48#include <linux/mount.h> 49#include <linux/netfilter_ipv4.h> 50#include <linux/netfilter_ipv6.h> 51#include <linux/tty.h> 52#include <net/icmp.h> 53#include <net/ip.h> /* for local_port_range[] */ 54#include <net/sock.h> 55#include <net/tcp.h> /* struct or_callable used in sock_rcv_skb */ 56#include <net/inet_connection_sock.h> 57#include <net/net_namespace.h> 58#include <net/netlabel.h> 59#include <linux/uaccess.h> 60#include <asm/ioctls.h> 61#include <linux/atomic.h> 62#include <linux/bitops.h> 63#include <linux/interrupt.h> 64#include <linux/netdevice.h> /* for network interface checks */ 65#include <net/netlink.h> 66#include <linux/tcp.h> 67#include <linux/udp.h> 68#include <linux/dccp.h> 69#include <linux/quota.h> 70#include <linux/un.h> /* for Unix socket types */ 71#include <net/af_unix.h> /* for Unix socket types */ 72#include <linux/parser.h> 73#include <linux/nfs_mount.h> 74#include <net/ipv6.h> 75#include <linux/hugetlb.h> 76#include <linux/personality.h> 77#include <linux/audit.h> 78#include <linux/string.h> 79#include <linux/selinux.h> 80#include <linux/mutex.h> 81#include <linux/posix-timers.h> 82#include <linux/syslog.h> 83#include <linux/user_namespace.h> 84#include <linux/export.h> 85#include <linux/msg.h> 86#include <linux/shm.h> 87 88#include "avc.h" 89#include "objsec.h" 90#include "netif.h" 91#include "netnode.h" 92#include "netport.h" 93#include "xfrm.h" 94#include "netlabel.h" 95#include "audit.h" 96#include "avc_ss.h" 97 98extern struct security_operations *security_ops; 99 100/* SECMARK reference count */ 101static atomic_t selinux_secmark_refcount = ATOMIC_INIT(0); 102 103#ifdef CONFIG_SECURITY_SELINUX_DEVELOP 104int selinux_enforcing; 105 106static int __init enforcing_setup(char *str) 107{ 108 unsigned long enforcing; 109 if (!strict_strtoul(str, 0, &enforcing)) 110 selinux_enforcing = enforcing ? 1 : 0; 111 return 1; 112} 113__setup("enforcing=", enforcing_setup); 114#endif 115 116#ifdef CONFIG_SECURITY_SELINUX_BOOTPARAM 117int selinux_enabled = CONFIG_SECURITY_SELINUX_BOOTPARAM_VALUE; 118 119static int __init selinux_enabled_setup(char *str) 120{ 121 unsigned long enabled; 122 if (!strict_strtoul(str, 0, &enabled)) 123 selinux_enabled = enabled ? 1 : 0; 124 return 1; 125} 126__setup("selinux=", selinux_enabled_setup); 127#else 128int selinux_enabled = 1; 129#endif 130 131static struct kmem_cache *sel_inode_cache; 132 133/** 134 * selinux_secmark_enabled - Check to see if SECMARK is currently enabled 135 * 136 * Description: 137 * This function checks the SECMARK reference counter to see if any SECMARK 138 * targets are currently configured, if the reference counter is greater than 139 * zero SECMARK is considered to be enabled. Returns true (1) if SECMARK is 140 * enabled, false (0) if SECMARK is disabled. If the always_check_network 141 * policy capability is enabled, SECMARK is always considered enabled. 142 * 143 */ 144static int selinux_secmark_enabled(void) 145{ 146 return (selinux_policycap_alwaysnetwork || atomic_read(&selinux_secmark_refcount)); 147} 148 149/** 150 * selinux_peerlbl_enabled - Check to see if peer labeling is currently enabled 151 * 152 * Description: 153 * This function checks if NetLabel or labeled IPSEC is enabled. Returns true 154 * (1) if any are enabled or false (0) if neither are enabled. If the 155 * always_check_network policy capability is enabled, peer labeling 156 * is always considered enabled. 157 * 158 */ 159static int selinux_peerlbl_enabled(void) 160{ 161 return (selinux_policycap_alwaysnetwork || netlbl_enabled() || selinux_xfrm_enabled()); 162} 163 164/* 165 * initialise the security for the init task 166 */ 167static void cred_init_security(void) 168{ 169 struct cred *cred = (struct cred *) current->real_cred; 170 struct task_security_struct *tsec; 171 172 tsec = kzalloc(sizeof(struct task_security_struct), GFP_KERNEL); 173 if (!tsec) 174 panic("SELinux: Failed to initialize initial task.\n"); 175 176 tsec->osid = tsec->sid = SECINITSID_KERNEL; 177 cred->security = tsec; 178} 179 180/* 181 * get the security ID of a set of credentials 182 */ 183static inline u32 cred_sid(const struct cred *cred) 184{ 185 const struct task_security_struct *tsec; 186 187 tsec = cred->security; 188 return tsec->sid; 189} 190 191/* 192 * get the objective security ID of a task 193 */ 194static inline u32 task_sid(const struct task_struct *task) 195{ 196 u32 sid; 197 198 rcu_read_lock(); 199 sid = cred_sid(__task_cred(task)); 200 rcu_read_unlock(); 201 return sid; 202} 203 204/* 205 * get the subjective security ID of the current task 206 */ 207static inline u32 current_sid(void) 208{ 209 const struct task_security_struct *tsec = current_security(); 210 211 return tsec->sid; 212} 213 214/* Allocate and free functions for each kind of security blob. */ 215 216static int inode_alloc_security(struct inode *inode) 217{ 218 struct inode_security_struct *isec; 219 u32 sid = current_sid(); 220 221 isec = kmem_cache_zalloc(sel_inode_cache, GFP_NOFS); 222 if (!isec) 223 return -ENOMEM; 224 225 mutex_init(&isec->lock); 226 INIT_LIST_HEAD(&isec->list); 227 isec->inode = inode; 228 isec->sid = SECINITSID_UNLABELED; 229 isec->sclass = SECCLASS_FILE; 230 isec->task_sid = sid; 231 inode->i_security = isec; 232 233 return 0; 234} 235 236static void inode_free_rcu(struct rcu_head *head) 237{ 238 struct inode_security_struct *isec; 239 240 isec = container_of(head, struct inode_security_struct, rcu); 241 kmem_cache_free(sel_inode_cache, isec); 242} 243 244static void inode_free_security(struct inode *inode) 245{ 246 struct inode_security_struct *isec = inode->i_security; 247 struct superblock_security_struct *sbsec = inode->i_sb->s_security; 248 249 spin_lock(&sbsec->isec_lock); 250 if (!list_empty(&isec->list)) 251 list_del_init(&isec->list); 252 spin_unlock(&sbsec->isec_lock); 253 254 /* 255 * The inode may still be referenced in a path walk and 256 * a call to selinux_inode_permission() can be made 257 * after inode_free_security() is called. Ideally, the VFS 258 * wouldn't do this, but fixing that is a much harder 259 * job. For now, simply free the i_security via RCU, and 260 * leave the current inode->i_security pointer intact. 261 * The inode will be freed after the RCU grace period too. 262 */ 263 call_rcu(&isec->rcu, inode_free_rcu); 264} 265 266static int file_alloc_security(struct file *file) 267{ 268 struct file_security_struct *fsec; 269 u32 sid = current_sid(); 270 271 fsec = kzalloc(sizeof(struct file_security_struct), GFP_KERNEL); 272 if (!fsec) 273 return -ENOMEM; 274 275 fsec->sid = sid; 276 fsec->fown_sid = sid; 277 file->f_security = fsec; 278 279 return 0; 280} 281 282static void file_free_security(struct file *file) 283{ 284 struct file_security_struct *fsec = file->f_security; 285 file->f_security = NULL; 286 kfree(fsec); 287} 288 289static int superblock_alloc_security(struct super_block *sb) 290{ 291 struct superblock_security_struct *sbsec; 292 293 sbsec = kzalloc(sizeof(struct superblock_security_struct), GFP_KERNEL); 294 if (!sbsec) 295 return -ENOMEM; 296 297 mutex_init(&sbsec->lock); 298 INIT_LIST_HEAD(&sbsec->isec_head); 299 spin_lock_init(&sbsec->isec_lock); 300 sbsec->sb = sb; 301 sbsec->sid = SECINITSID_UNLABELED; 302 sbsec->def_sid = SECINITSID_FILE; 303 sbsec->mntpoint_sid = SECINITSID_UNLABELED; 304 sb->s_security = sbsec; 305 306 return 0; 307} 308 309static void superblock_free_security(struct super_block *sb) 310{ 311 struct superblock_security_struct *sbsec = sb->s_security; 312 sb->s_security = NULL; 313 kfree(sbsec); 314} 315 316/* The file system's label must be initialized prior to use. */ 317 318static const char *labeling_behaviors[7] = { 319 "uses xattr", 320 "uses transition SIDs", 321 "uses task SIDs", 322 "uses genfs_contexts", 323 "not configured for labeling", 324 "uses mountpoint labeling", 325 "uses native labeling", 326}; 327 328static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dentry); 329 330static inline int inode_doinit(struct inode *inode) 331{ 332 return inode_doinit_with_dentry(inode, NULL); 333} 334 335enum { 336 Opt_error = -1, 337 Opt_context = 1, 338 Opt_fscontext = 2, 339 Opt_defcontext = 3, 340 Opt_rootcontext = 4, 341 Opt_labelsupport = 5, 342 Opt_nextmntopt = 6, 343}; 344 345#define NUM_SEL_MNT_OPTS (Opt_nextmntopt - 1) 346 347static const match_table_t tokens = { 348 {Opt_context, CONTEXT_STR "%s"}, 349 {Opt_fscontext, FSCONTEXT_STR "%s"}, 350 {Opt_defcontext, DEFCONTEXT_STR "%s"}, 351 {Opt_rootcontext, ROOTCONTEXT_STR "%s"}, 352 {Opt_labelsupport, LABELSUPP_STR}, 353 {Opt_error, NULL}, 354}; 355 356#define SEL_MOUNT_FAIL_MSG "SELinux: duplicate or incompatible mount options\n" 357 358static int may_context_mount_sb_relabel(u32 sid, 359 struct superblock_security_struct *sbsec, 360 const struct cred *cred) 361{ 362 const struct task_security_struct *tsec = cred->security; 363 int rc; 364 365 rc = avc_has_perm(tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM, 366 FILESYSTEM__RELABELFROM, NULL); 367 if (rc) 368 return rc; 369 370 rc = avc_has_perm(tsec->sid, sid, SECCLASS_FILESYSTEM, 371 FILESYSTEM__RELABELTO, NULL); 372 return rc; 373} 374 375static int may_context_mount_inode_relabel(u32 sid, 376 struct superblock_security_struct *sbsec, 377 const struct cred *cred) 378{ 379 const struct task_security_struct *tsec = cred->security; 380 int rc; 381 rc = avc_has_perm(tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM, 382 FILESYSTEM__RELABELFROM, NULL); 383 if (rc) 384 return rc; 385 386 rc = avc_has_perm(sid, sbsec->sid, SECCLASS_FILESYSTEM, 387 FILESYSTEM__ASSOCIATE, NULL); 388 return rc; 389} 390 391static int selinux_is_sblabel_mnt(struct super_block *sb) 392{ 393 struct superblock_security_struct *sbsec = sb->s_security; 394 395 if (sbsec->behavior == SECURITY_FS_USE_XATTR || 396 sbsec->behavior == SECURITY_FS_USE_TRANS || 397 sbsec->behavior == SECURITY_FS_USE_TASK) 398 return 1; 399 400 /* Special handling for sysfs. Is genfs but also has setxattr handler*/ 401 if (strncmp(sb->s_type->name, "sysfs", sizeof("sysfs")) == 0) 402 return 1; 403 404 /* 405 * Special handling for rootfs. Is genfs but supports 406 * setting SELinux context on in-core inodes. 407 */ 408 if (strncmp(sb->s_type->name, "rootfs", sizeof("rootfs")) == 0) 409 return 1; 410 411 return 0; 412} 413 414static int sb_finish_set_opts(struct super_block *sb) 415{ 416 struct superblock_security_struct *sbsec = sb->s_security; 417 struct dentry *root = sb->s_root; 418 struct inode *root_inode = root->d_inode; 419 int rc = 0; 420 421 if (sbsec->behavior == SECURITY_FS_USE_XATTR) { 422 /* Make sure that the xattr handler exists and that no 423 error other than -ENODATA is returned by getxattr on 424 the root directory. -ENODATA is ok, as this may be 425 the first boot of the SELinux kernel before we have 426 assigned xattr values to the filesystem. */ 427 if (!root_inode->i_op->getxattr) { 428 printk(KERN_WARNING "SELinux: (dev %s, type %s) has no " 429 "xattr support\n", sb->s_id, sb->s_type->name); 430 rc = -EOPNOTSUPP; 431 goto out; 432 } 433 rc = root_inode->i_op->getxattr(root, XATTR_NAME_SELINUX, NULL, 0); 434 if (rc < 0 && rc != -ENODATA) { 435 if (rc == -EOPNOTSUPP) 436 printk(KERN_WARNING "SELinux: (dev %s, type " 437 "%s) has no security xattr handler\n", 438 sb->s_id, sb->s_type->name); 439 else 440 printk(KERN_WARNING "SELinux: (dev %s, type " 441 "%s) getxattr errno %d\n", sb->s_id, 442 sb->s_type->name, -rc); 443 goto out; 444 } 445 } 446 447 if (sbsec->behavior > ARRAY_SIZE(labeling_behaviors)) 448 printk(KERN_ERR "SELinux: initialized (dev %s, type %s), unknown behavior\n", 449 sb->s_id, sb->s_type->name); 450 else 451 printk(KERN_DEBUG "SELinux: initialized (dev %s, type %s), %s\n", 452 sb->s_id, sb->s_type->name, 453 labeling_behaviors[sbsec->behavior-1]); 454 455 sbsec->flags |= SE_SBINITIALIZED; 456 if (selinux_is_sblabel_mnt(sb)) 457 sbsec->flags |= SBLABEL_MNT; 458 459 /* Initialize the root inode. */ 460 rc = inode_doinit_with_dentry(root_inode, root); 461 462 /* Initialize any other inodes associated with the superblock, e.g. 463 inodes created prior to initial policy load or inodes created 464 during get_sb by a pseudo filesystem that directly 465 populates itself. */ 466 spin_lock(&sbsec->isec_lock); 467next_inode: 468 if (!list_empty(&sbsec->isec_head)) { 469 struct inode_security_struct *isec = 470 list_entry(sbsec->isec_head.next, 471 struct inode_security_struct, list); 472 struct inode *inode = isec->inode; 473 spin_unlock(&sbsec->isec_lock); 474 inode = igrab(inode); 475 if (inode) { 476 if (!IS_PRIVATE(inode)) 477 inode_doinit(inode); 478 iput(inode); 479 } 480 spin_lock(&sbsec->isec_lock); 481 list_del_init(&isec->list); 482 goto next_inode; 483 } 484 spin_unlock(&sbsec->isec_lock); 485out: 486 return rc; 487} 488 489/* 490 * This function should allow an FS to ask what it's mount security 491 * options were so it can use those later for submounts, displaying 492 * mount options, or whatever. 493 */ 494static int selinux_get_mnt_opts(const struct super_block *sb, 495 struct security_mnt_opts *opts) 496{ 497 int rc = 0, i; 498 struct superblock_security_struct *sbsec = sb->s_security; 499 char *context = NULL; 500 u32 len; 501 char tmp; 502 503 security_init_mnt_opts(opts); 504 505 if (!(sbsec->flags & SE_SBINITIALIZED)) 506 return -EINVAL; 507 508 if (!ss_initialized) 509 return -EINVAL; 510 511 /* make sure we always check enough bits to cover the mask */ 512 BUILD_BUG_ON(SE_MNTMASK >= (1 << NUM_SEL_MNT_OPTS)); 513 514 tmp = sbsec->flags & SE_MNTMASK; 515 /* count the number of mount options for this sb */ 516 for (i = 0; i < NUM_SEL_MNT_OPTS; i++) { 517 if (tmp & 0x01) 518 opts->num_mnt_opts++; 519 tmp >>= 1; 520 } 521 /* Check if the Label support flag is set */ 522 if (sbsec->flags & SBLABEL_MNT) 523 opts->num_mnt_opts++; 524 525 opts->mnt_opts = kcalloc(opts->num_mnt_opts, sizeof(char *), GFP_ATOMIC); 526 if (!opts->mnt_opts) { 527 rc = -ENOMEM; 528 goto out_free; 529 } 530 531 opts->mnt_opts_flags = kcalloc(opts->num_mnt_opts, sizeof(int), GFP_ATOMIC); 532 if (!opts->mnt_opts_flags) { 533 rc = -ENOMEM; 534 goto out_free; 535 } 536 537 i = 0; 538 if (sbsec->flags & FSCONTEXT_MNT) { 539 rc = security_sid_to_context(sbsec->sid, &context, &len); 540 if (rc) 541 goto out_free; 542 opts->mnt_opts[i] = context; 543 opts->mnt_opts_flags[i++] = FSCONTEXT_MNT; 544 } 545 if (sbsec->flags & CONTEXT_MNT) { 546 rc = security_sid_to_context(sbsec->mntpoint_sid, &context, &len); 547 if (rc) 548 goto out_free; 549 opts->mnt_opts[i] = context; 550 opts->mnt_opts_flags[i++] = CONTEXT_MNT; 551 } 552 if (sbsec->flags & DEFCONTEXT_MNT) { 553 rc = security_sid_to_context(sbsec->def_sid, &context, &len); 554 if (rc) 555 goto out_free; 556 opts->mnt_opts[i] = context; 557 opts->mnt_opts_flags[i++] = DEFCONTEXT_MNT; 558 } 559 if (sbsec->flags & ROOTCONTEXT_MNT) { 560 struct inode *root = sbsec->sb->s_root->d_inode; 561 struct inode_security_struct *isec = root->i_security; 562 563 rc = security_sid_to_context(isec->sid, &context, &len); 564 if (rc) 565 goto out_free; 566 opts->mnt_opts[i] = context; 567 opts->mnt_opts_flags[i++] = ROOTCONTEXT_MNT; 568 } 569 if (sbsec->flags & SBLABEL_MNT) { 570 opts->mnt_opts[i] = NULL; 571 opts->mnt_opts_flags[i++] = SBLABEL_MNT; 572 } 573 574 BUG_ON(i != opts->num_mnt_opts); 575 576 return 0; 577 578out_free: 579 security_free_mnt_opts(opts); 580 return rc; 581} 582 583static int bad_option(struct superblock_security_struct *sbsec, char flag, 584 u32 old_sid, u32 new_sid) 585{ 586 char mnt_flags = sbsec->flags & SE_MNTMASK; 587 588 /* check if the old mount command had the same options */ 589 if (sbsec->flags & SE_SBINITIALIZED) 590 if (!(sbsec->flags & flag) || 591 (old_sid != new_sid)) 592 return 1; 593 594 /* check if we were passed the same options twice, 595 * aka someone passed context=a,context=b 596 */ 597 if (!(sbsec->flags & SE_SBINITIALIZED)) 598 if (mnt_flags & flag) 599 return 1; 600 return 0; 601} 602 603/* 604 * Allow filesystems with binary mount data to explicitly set mount point 605 * labeling information. 606 */ 607static int selinux_set_mnt_opts(struct super_block *sb, 608 struct security_mnt_opts *opts, 609 unsigned long kern_flags, 610 unsigned long *set_kern_flags) 611{ 612 const struct cred *cred = current_cred(); 613 int rc = 0, i; 614 struct superblock_security_struct *sbsec = sb->s_security; 615 const char *name = sb->s_type->name; 616 struct inode *inode = sbsec->sb->s_root->d_inode; 617 struct inode_security_struct *root_isec = inode->i_security; 618 u32 fscontext_sid = 0, context_sid = 0, rootcontext_sid = 0; 619 u32 defcontext_sid = 0; 620 char **mount_options = opts->mnt_opts; 621 int *flags = opts->mnt_opts_flags; 622 int num_opts = opts->num_mnt_opts; 623 624 mutex_lock(&sbsec->lock); 625 626 if (!ss_initialized) { 627 if (!num_opts) { 628 /* Defer initialization until selinux_complete_init, 629 after the initial policy is loaded and the security 630 server is ready to handle calls. */ 631 goto out; 632 } 633 rc = -EINVAL; 634 printk(KERN_WARNING "SELinux: Unable to set superblock options " 635 "before the security server is initialized\n"); 636 goto out; 637 } 638 if (kern_flags && !set_kern_flags) { 639 /* Specifying internal flags without providing a place to 640 * place the results is not allowed */ 641 rc = -EINVAL; 642 goto out; 643 } 644 645 /* 646 * Binary mount data FS will come through this function twice. Once 647 * from an explicit call and once from the generic calls from the vfs. 648 * Since the generic VFS calls will not contain any security mount data 649 * we need to skip the double mount verification. 650 * 651 * This does open a hole in which we will not notice if the first 652 * mount using this sb set explict options and a second mount using 653 * this sb does not set any security options. (The first options 654 * will be used for both mounts) 655 */ 656 if ((sbsec->flags & SE_SBINITIALIZED) && (sb->s_type->fs_flags & FS_BINARY_MOUNTDATA) 657 && (num_opts == 0)) 658 goto out; 659 660 /* 661 * parse the mount options, check if they are valid sids. 662 * also check if someone is trying to mount the same sb more 663 * than once with different security options. 664 */ 665 for (i = 0; i < num_opts; i++) { 666 u32 sid; 667 668 if (flags[i] == SBLABEL_MNT) 669 continue; 670 rc = security_context_to_sid(mount_options[i], 671 strlen(mount_options[i]), &sid, GFP_KERNEL); 672 if (rc) { 673 printk(KERN_WARNING "SELinux: security_context_to_sid" 674 "(%s) failed for (dev %s, type %s) errno=%d\n", 675 mount_options[i], sb->s_id, name, rc); 676 goto out; 677 } 678 switch (flags[i]) { 679 case FSCONTEXT_MNT: 680 fscontext_sid = sid; 681 682 if (bad_option(sbsec, FSCONTEXT_MNT, sbsec->sid, 683 fscontext_sid)) 684 goto out_double_mount; 685 686 sbsec->flags |= FSCONTEXT_MNT; 687 break; 688 case CONTEXT_MNT: 689 context_sid = sid; 690 691 if (bad_option(sbsec, CONTEXT_MNT, sbsec->mntpoint_sid, 692 context_sid)) 693 goto out_double_mount; 694 695 sbsec->flags |= CONTEXT_MNT; 696 break; 697 case ROOTCONTEXT_MNT: 698 rootcontext_sid = sid; 699 700 if (bad_option(sbsec, ROOTCONTEXT_MNT, root_isec->sid, 701 rootcontext_sid)) 702 goto out_double_mount; 703 704 sbsec->flags |= ROOTCONTEXT_MNT; 705 706 break; 707 case DEFCONTEXT_MNT: 708 defcontext_sid = sid; 709 710 if (bad_option(sbsec, DEFCONTEXT_MNT, sbsec->def_sid, 711 defcontext_sid)) 712 goto out_double_mount; 713 714 sbsec->flags |= DEFCONTEXT_MNT; 715 716 break; 717 default: 718 rc = -EINVAL; 719 goto out; 720 } 721 } 722 723 if (sbsec->flags & SE_SBINITIALIZED) { 724 /* previously mounted with options, but not on this attempt? */ 725 if ((sbsec->flags & SE_MNTMASK) && !num_opts) 726 goto out_double_mount; 727 rc = 0; 728 goto out; 729 } 730 731 if (strcmp(sb->s_type->name, "proc") == 0) 732 sbsec->flags |= SE_SBPROC; 733 734 if (!sbsec->behavior) { 735 /* 736 * Determine the labeling behavior to use for this 737 * filesystem type. 738 */ 739 rc = security_fs_use(sb); 740 if (rc) { 741 printk(KERN_WARNING 742 "%s: security_fs_use(%s) returned %d\n", 743 __func__, sb->s_type->name, rc); 744 goto out; 745 } 746 } 747 /* sets the context of the superblock for the fs being mounted. */ 748 if (fscontext_sid) { 749 rc = may_context_mount_sb_relabel(fscontext_sid, sbsec, cred); 750 if (rc) 751 goto out; 752 753 sbsec->sid = fscontext_sid; 754 } 755 756 /* 757 * Switch to using mount point labeling behavior. 758 * sets the label used on all file below the mountpoint, and will set 759 * the superblock context if not already set. 760 */ 761 if (kern_flags & SECURITY_LSM_NATIVE_LABELS && !context_sid) { 762 sbsec->behavior = SECURITY_FS_USE_NATIVE; 763 *set_kern_flags |= SECURITY_LSM_NATIVE_LABELS; 764 } 765 766 if (context_sid) { 767 if (!fscontext_sid) { 768 rc = may_context_mount_sb_relabel(context_sid, sbsec, 769 cred); 770 if (rc) 771 goto out; 772 sbsec->sid = context_sid; 773 } else { 774 rc = may_context_mount_inode_relabel(context_sid, sbsec, 775 cred); 776 if (rc) 777 goto out; 778 } 779 if (!rootcontext_sid) 780 rootcontext_sid = context_sid; 781 782 sbsec->mntpoint_sid = context_sid; 783 sbsec->behavior = SECURITY_FS_USE_MNTPOINT; 784 } 785 786 if (rootcontext_sid) { 787 rc = may_context_mount_inode_relabel(rootcontext_sid, sbsec, 788 cred); 789 if (rc) 790 goto out; 791 792 root_isec->sid = rootcontext_sid; 793 root_isec->initialized = 1; 794 } 795 796 if (defcontext_sid) { 797 if (sbsec->behavior != SECURITY_FS_USE_XATTR && 798 sbsec->behavior != SECURITY_FS_USE_NATIVE) { 799 rc = -EINVAL; 800 printk(KERN_WARNING "SELinux: defcontext option is " 801 "invalid for this filesystem type\n"); 802 goto out; 803 } 804 805 if (defcontext_sid != sbsec->def_sid) { 806 rc = may_context_mount_inode_relabel(defcontext_sid, 807 sbsec, cred); 808 if (rc) 809 goto out; 810 } 811 812 sbsec->def_sid = defcontext_sid; 813 } 814 815 rc = sb_finish_set_opts(sb); 816out: 817 mutex_unlock(&sbsec->lock); 818 return rc; 819out_double_mount: 820 rc = -EINVAL; 821 printk(KERN_WARNING "SELinux: mount invalid. Same superblock, different " 822 "security settings for (dev %s, type %s)\n", sb->s_id, name); 823 goto out; 824} 825 826static int selinux_cmp_sb_context(const struct super_block *oldsb, 827 const struct super_block *newsb) 828{ 829 struct superblock_security_struct *old = oldsb->s_security; 830 struct superblock_security_struct *new = newsb->s_security; 831 char oldflags = old->flags & SE_MNTMASK; 832 char newflags = new->flags & SE_MNTMASK; 833 834 if (oldflags != newflags) 835 goto mismatch; 836 if ((oldflags & FSCONTEXT_MNT) && old->sid != new->sid) 837 goto mismatch; 838 if ((oldflags & CONTEXT_MNT) && old->mntpoint_sid != new->mntpoint_sid) 839 goto mismatch; 840 if ((oldflags & DEFCONTEXT_MNT) && old->def_sid != new->def_sid) 841 goto mismatch; 842 if (oldflags & ROOTCONTEXT_MNT) { 843 struct inode_security_struct *oldroot = oldsb->s_root->d_inode->i_security; 844 struct inode_security_struct *newroot = newsb->s_root->d_inode->i_security; 845 if (oldroot->sid != newroot->sid) 846 goto mismatch; 847 } 848 return 0; 849mismatch: 850 printk(KERN_WARNING "SELinux: mount invalid. Same superblock, " 851 "different security settings for (dev %s, " 852 "type %s)\n", newsb->s_id, newsb->s_type->name); 853 return -EBUSY; 854} 855 856static int selinux_sb_clone_mnt_opts(const struct super_block *oldsb, 857 struct super_block *newsb) 858{ 859 const struct superblock_security_struct *oldsbsec = oldsb->s_security; 860 struct superblock_security_struct *newsbsec = newsb->s_security; 861 862 int set_fscontext = (oldsbsec->flags & FSCONTEXT_MNT); 863 int set_context = (oldsbsec->flags & CONTEXT_MNT); 864 int set_rootcontext = (oldsbsec->flags & ROOTCONTEXT_MNT); 865 866 /* 867 * if the parent was able to be mounted it clearly had no special lsm 868 * mount options. thus we can safely deal with this superblock later 869 */ 870 if (!ss_initialized) 871 return 0; 872 873 /* how can we clone if the old one wasn't set up?? */ 874 BUG_ON(!(oldsbsec->flags & SE_SBINITIALIZED)); 875 876 /* if fs is reusing a sb, make sure that the contexts match */ 877 if (newsbsec->flags & SE_SBINITIALIZED) 878 return selinux_cmp_sb_context(oldsb, newsb); 879 880 mutex_lock(&newsbsec->lock); 881 882 newsbsec->flags = oldsbsec->flags; 883 884 newsbsec->sid = oldsbsec->sid; 885 newsbsec->def_sid = oldsbsec->def_sid; 886 newsbsec->behavior = oldsbsec->behavior; 887 888 if (set_context) { 889 u32 sid = oldsbsec->mntpoint_sid; 890 891 if (!set_fscontext) 892 newsbsec->sid = sid; 893 if (!set_rootcontext) { 894 struct inode *newinode = newsb->s_root->d_inode; 895 struct inode_security_struct *newisec = newinode->i_security; 896 newisec->sid = sid; 897 } 898 newsbsec->mntpoint_sid = sid; 899 } 900 if (set_rootcontext) { 901 const struct inode *oldinode = oldsb->s_root->d_inode; 902 const struct inode_security_struct *oldisec = oldinode->i_security; 903 struct inode *newinode = newsb->s_root->d_inode; 904 struct inode_security_struct *newisec = newinode->i_security; 905 906 newisec->sid = oldisec->sid; 907 } 908 909 sb_finish_set_opts(newsb); 910 mutex_unlock(&newsbsec->lock); 911 return 0; 912} 913 914static int selinux_parse_opts_str(char *options, 915 struct security_mnt_opts *opts) 916{ 917 char *p; 918 char *context = NULL, *defcontext = NULL; 919 char *fscontext = NULL, *rootcontext = NULL; 920 int rc, num_mnt_opts = 0; 921 922 opts->num_mnt_opts = 0; 923 924 /* Standard string-based options. */ 925 while ((p = strsep(&options, "|")) != NULL) { 926 int token; 927 substring_t args[MAX_OPT_ARGS]; 928 929 if (!*p) 930 continue; 931 932 token = match_token(p, tokens, args); 933 934 switch (token) { 935 case Opt_context: 936 if (context || defcontext) { 937 rc = -EINVAL; 938 printk(KERN_WARNING SEL_MOUNT_FAIL_MSG); 939 goto out_err; 940 } 941 context = match_strdup(&args[0]); 942 if (!context) { 943 rc = -ENOMEM; 944 goto out_err; 945 } 946 break; 947 948 case Opt_fscontext: 949 if (fscontext) { 950 rc = -EINVAL; 951 printk(KERN_WARNING SEL_MOUNT_FAIL_MSG); 952 goto out_err; 953 } 954 fscontext = match_strdup(&args[0]); 955 if (!fscontext) { 956 rc = -ENOMEM; 957 goto out_err; 958 } 959 break; 960 961 case Opt_rootcontext: 962 if (rootcontext) { 963 rc = -EINVAL; 964 printk(KERN_WARNING SEL_MOUNT_FAIL_MSG); 965 goto out_err; 966 } 967 rootcontext = match_strdup(&args[0]); 968 if (!rootcontext) { 969 rc = -ENOMEM; 970 goto out_err; 971 } 972 break; 973 974 case Opt_defcontext: 975 if (context || defcontext) { 976 rc = -EINVAL; 977 printk(KERN_WARNING SEL_MOUNT_FAIL_MSG); 978 goto out_err; 979 } 980 defcontext = match_strdup(&args[0]); 981 if (!defcontext) { 982 rc = -ENOMEM; 983 goto out_err; 984 } 985 break; 986 case Opt_labelsupport: 987 break; 988 default: 989 rc = -EINVAL; 990 printk(KERN_WARNING "SELinux: unknown mount option\n"); 991 goto out_err; 992 993 } 994 } 995 996 rc = -ENOMEM; 997 opts->mnt_opts = kcalloc(NUM_SEL_MNT_OPTS, sizeof(char *), GFP_ATOMIC); 998 if (!opts->mnt_opts) 999 goto out_err; 1000 1001 opts->mnt_opts_flags = kcalloc(NUM_SEL_MNT_OPTS, sizeof(int), GFP_ATOMIC); 1002 if (!opts->mnt_opts_flags) { 1003 kfree(opts->mnt_opts); 1004 goto out_err; 1005 } 1006 1007 if (fscontext) { 1008 opts->mnt_opts[num_mnt_opts] = fscontext; 1009 opts->mnt_opts_flags[num_mnt_opts++] = FSCONTEXT_MNT; 1010 } 1011 if (context) { 1012 opts->mnt_opts[num_mnt_opts] = context; 1013 opts->mnt_opts_flags[num_mnt_opts++] = CONTEXT_MNT; 1014 } 1015 if (rootcontext) { 1016 opts->mnt_opts[num_mnt_opts] = rootcontext; 1017 opts->mnt_opts_flags[num_mnt_opts++] = ROOTCONTEXT_MNT; 1018 } 1019 if (defcontext) { 1020 opts->mnt_opts[num_mnt_opts] = defcontext; 1021 opts->mnt_opts_flags[num_mnt_opts++] = DEFCONTEXT_MNT; 1022 } 1023 1024 opts->num_mnt_opts = num_mnt_opts; 1025 return 0; 1026 1027out_err: 1028 kfree(context); 1029 kfree(defcontext); 1030 kfree(fscontext); 1031 kfree(rootcontext); 1032 return rc; 1033} 1034/* 1035 * string mount options parsing and call set the sbsec 1036 */ 1037static int superblock_doinit(struct super_block *sb, void *data) 1038{ 1039 int rc = 0; 1040 char *options = data; 1041 struct security_mnt_opts opts; 1042 1043 security_init_mnt_opts(&opts); 1044 1045 if (!data) 1046 goto out; 1047 1048 BUG_ON(sb->s_type->fs_flags & FS_BINARY_MOUNTDATA); 1049 1050 rc = selinux_parse_opts_str(options, &opts); 1051 if (rc) 1052 goto out_err; 1053 1054out: 1055 rc = selinux_set_mnt_opts(sb, &opts, 0, NULL); 1056 1057out_err: 1058 security_free_mnt_opts(&opts); 1059 return rc; 1060} 1061 1062static void selinux_write_opts(struct seq_file *m, 1063 struct security_mnt_opts *opts) 1064{ 1065 int i; 1066 char *prefix; 1067 1068 for (i = 0; i < opts->num_mnt_opts; i++) { 1069 char *has_comma; 1070 1071 if (opts->mnt_opts[i]) 1072 has_comma = strchr(opts->mnt_opts[i], ','); 1073 else 1074 has_comma = NULL; 1075 1076 switch (opts->mnt_opts_flags[i]) { 1077 case CONTEXT_MNT: 1078 prefix = CONTEXT_STR; 1079 break; 1080 case FSCONTEXT_MNT: 1081 prefix = FSCONTEXT_STR; 1082 break; 1083 case ROOTCONTEXT_MNT: 1084 prefix = ROOTCONTEXT_STR; 1085 break; 1086 case DEFCONTEXT_MNT: 1087 prefix = DEFCONTEXT_STR; 1088 break; 1089 case SBLABEL_MNT: 1090 seq_putc(m, ','); 1091 seq_puts(m, LABELSUPP_STR); 1092 continue; 1093 default: 1094 BUG(); 1095 return; 1096 }; 1097 /* we need a comma before each option */ 1098 seq_putc(m, ','); 1099 seq_puts(m, prefix); 1100 if (has_comma) 1101 seq_putc(m, '\"'); 1102 seq_puts(m, opts->mnt_opts[i]); 1103 if (has_comma) 1104 seq_putc(m, '\"'); 1105 } 1106} 1107 1108static int selinux_sb_show_options(struct seq_file *m, struct super_block *sb) 1109{ 1110 struct security_mnt_opts opts; 1111 int rc; 1112 1113 rc = selinux_get_mnt_opts(sb, &opts); 1114 if (rc) { 1115 /* before policy load we may get EINVAL, don't show anything */ 1116 if (rc == -EINVAL) 1117 rc = 0; 1118 return rc; 1119 } 1120 1121 selinux_write_opts(m, &opts); 1122 1123 security_free_mnt_opts(&opts); 1124 1125 return rc; 1126} 1127 1128static inline u16 inode_mode_to_security_class(umode_t mode) 1129{ 1130 switch (mode & S_IFMT) { 1131 case S_IFSOCK: 1132 return SECCLASS_SOCK_FILE; 1133 case S_IFLNK: 1134 return SECCLASS_LNK_FILE; 1135 case S_IFREG: 1136 return SECCLASS_FILE; 1137 case S_IFBLK: 1138 return SECCLASS_BLK_FILE; 1139 case S_IFDIR: 1140 return SECCLASS_DIR; 1141 case S_IFCHR: 1142 return SECCLASS_CHR_FILE; 1143 case S_IFIFO: 1144 return SECCLASS_FIFO_FILE; 1145 1146 } 1147 1148 return SECCLASS_FILE; 1149} 1150 1151static inline int default_protocol_stream(int protocol) 1152{ 1153 return (protocol == IPPROTO_IP || protocol == IPPROTO_TCP); 1154} 1155 1156static inline int default_protocol_dgram(int protocol) 1157{ 1158 return (protocol == IPPROTO_IP || protocol == IPPROTO_UDP); 1159} 1160 1161static inline u16 socket_type_to_security_class(int family, int type, int protocol) 1162{ 1163 switch (family) { 1164 case PF_UNIX: 1165 switch (type) { 1166 case SOCK_STREAM: 1167 case SOCK_SEQPACKET: 1168 return SECCLASS_UNIX_STREAM_SOCKET; 1169 case SOCK_DGRAM: 1170 return SECCLASS_UNIX_DGRAM_SOCKET; 1171 } 1172 break; 1173 case PF_INET: 1174 case PF_INET6: 1175 switch (type) { 1176 case SOCK_STREAM: 1177 if (default_protocol_stream(protocol)) 1178 return SECCLASS_TCP_SOCKET; 1179 else 1180 return SECCLASS_RAWIP_SOCKET; 1181 case SOCK_DGRAM: 1182 if (default_protocol_dgram(protocol)) 1183 return SECCLASS_UDP_SOCKET; 1184 else 1185 return SECCLASS_RAWIP_SOCKET; 1186 case SOCK_DCCP: 1187 return SECCLASS_DCCP_SOCKET; 1188 default: 1189 return SECCLASS_RAWIP_SOCKET; 1190 } 1191 break; 1192 case PF_NETLINK: 1193 switch (protocol) { 1194 case NETLINK_ROUTE: 1195 return SECCLASS_NETLINK_ROUTE_SOCKET; 1196 case NETLINK_FIREWALL: 1197 return SECCLASS_NETLINK_FIREWALL_SOCKET; 1198 case NETLINK_SOCK_DIAG: 1199 return SECCLASS_NETLINK_TCPDIAG_SOCKET; 1200 case NETLINK_NFLOG: 1201 return SECCLASS_NETLINK_NFLOG_SOCKET; 1202 case NETLINK_XFRM: 1203 return SECCLASS_NETLINK_XFRM_SOCKET; 1204 case NETLINK_SELINUX: 1205 return SECCLASS_NETLINK_SELINUX_SOCKET; 1206 case NETLINK_AUDIT: 1207 return SECCLASS_NETLINK_AUDIT_SOCKET; 1208 case NETLINK_IP6_FW: 1209 return SECCLASS_NETLINK_IP6FW_SOCKET; 1210 case NETLINK_DNRTMSG: 1211 return SECCLASS_NETLINK_DNRT_SOCKET; 1212 case NETLINK_KOBJECT_UEVENT: 1213 return SECCLASS_NETLINK_KOBJECT_UEVENT_SOCKET; 1214 default: 1215 return SECCLASS_NETLINK_SOCKET; 1216 } 1217 case PF_PACKET: 1218 return SECCLASS_PACKET_SOCKET; 1219 case PF_KEY: 1220 return SECCLASS_KEY_SOCKET; 1221 case PF_APPLETALK: 1222 return SECCLASS_APPLETALK_SOCKET; 1223 } 1224 1225 return SECCLASS_SOCKET; 1226} 1227 1228#ifdef CONFIG_PROC_FS 1229static int selinux_proc_get_sid(struct dentry *dentry, 1230 u16 tclass, 1231 u32 *sid) 1232{ 1233 int rc; 1234 char *buffer, *path; 1235 1236 buffer = (char *)__get_free_page(GFP_KERNEL); 1237 if (!buffer) 1238 return -ENOMEM; 1239 1240 path = dentry_path_raw(dentry, buffer, PAGE_SIZE); 1241 if (IS_ERR(path)) 1242 rc = PTR_ERR(path); 1243 else { 1244 /* each process gets a /proc/PID/ entry. Strip off the 1245 * PID part to get a valid selinux labeling. 1246 * e.g. /proc/1/net/rpc/nfs -> /net/rpc/nfs */ 1247 while (path[1] >= '0' && path[1] <= '9') { 1248 path[1] = '/'; 1249 path++; 1250 } 1251 rc = security_genfs_sid("proc", path, tclass, sid); 1252 } 1253 free_page((unsigned long)buffer); 1254 return rc; 1255} 1256#else 1257static int selinux_proc_get_sid(struct dentry *dentry, 1258 u16 tclass, 1259 u32 *sid) 1260{ 1261 return -EINVAL; 1262} 1263#endif 1264 1265/* The inode's security attributes must be initialized before first use. */ 1266static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dentry) 1267{ 1268 struct superblock_security_struct *sbsec = NULL; 1269 struct inode_security_struct *isec = inode->i_security; 1270 u32 sid; 1271 struct dentry *dentry; 1272#define INITCONTEXTLEN 255 1273 char *context = NULL; 1274 unsigned len = 0; 1275 int rc = 0; 1276 1277 if (isec->initialized) 1278 goto out; 1279 1280 mutex_lock(&isec->lock); 1281 if (isec->initialized) 1282 goto out_unlock; 1283 1284 sbsec = inode->i_sb->s_security; 1285 if (!(sbsec->flags & SE_SBINITIALIZED)) { 1286 /* Defer initialization until selinux_complete_init, 1287 after the initial policy is loaded and the security 1288 server is ready to handle calls. */ 1289 spin_lock(&sbsec->isec_lock); 1290 if (list_empty(&isec->list)) 1291 list_add(&isec->list, &sbsec->isec_head); 1292 spin_unlock(&sbsec->isec_lock); 1293 goto out_unlock; 1294 } 1295 1296 switch (sbsec->behavior) { 1297 case SECURITY_FS_USE_NATIVE: 1298 break; 1299 case SECURITY_FS_USE_XATTR: 1300 if (!inode->i_op->getxattr) { 1301 isec->sid = sbsec->def_sid; 1302 break; 1303 } 1304 1305 /* Need a dentry, since the xattr API requires one. 1306 Life would be simpler if we could just pass the inode. */ 1307 if (opt_dentry) { 1308 /* Called from d_instantiate or d_splice_alias. */ 1309 dentry = dget(opt_dentry); 1310 } else { 1311 /* Called from selinux_complete_init, try to find a dentry. */ 1312 dentry = d_find_alias(inode); 1313 } 1314 if (!dentry) { 1315 /* 1316 * this is can be hit on boot when a file is accessed 1317 * before the policy is loaded. When we load policy we 1318 * may find inodes that have no dentry on the 1319 * sbsec->isec_head list. No reason to complain as these 1320 * will get fixed up the next time we go through 1321 * inode_doinit with a dentry, before these inodes could 1322 * be used again by userspace. 1323 */ 1324 goto out_unlock; 1325 } 1326 1327 len = INITCONTEXTLEN; 1328 context = kmalloc(len+1, GFP_NOFS); 1329 if (!context) { 1330 rc = -ENOMEM; 1331 dput(dentry); 1332 goto out_unlock; 1333 } 1334 context[len] = '\0'; 1335 rc = inode->i_op->getxattr(dentry, XATTR_NAME_SELINUX, 1336 context, len); 1337 if (rc == -ERANGE) { 1338 kfree(context); 1339 1340 /* Need a larger buffer. Query for the right size. */ 1341 rc = inode->i_op->getxattr(dentry, XATTR_NAME_SELINUX, 1342 NULL, 0); 1343 if (rc < 0) { 1344 dput(dentry); 1345 goto out_unlock; 1346 } 1347 len = rc; 1348 context = kmalloc(len+1, GFP_NOFS); 1349 if (!context) { 1350 rc = -ENOMEM; 1351 dput(dentry); 1352 goto out_unlock; 1353 } 1354 context[len] = '\0'; 1355 rc = inode->i_op->getxattr(dentry, 1356 XATTR_NAME_SELINUX, 1357 context, len); 1358 } 1359 dput(dentry); 1360 if (rc < 0) { 1361 if (rc != -ENODATA) { 1362 printk(KERN_WARNING "SELinux: %s: getxattr returned " 1363 "%d for dev=%s ino=%ld\n", __func__, 1364 -rc, inode->i_sb->s_id, inode->i_ino); 1365 kfree(context); 1366 goto out_unlock; 1367 } 1368 /* Map ENODATA to the default file SID */ 1369 sid = sbsec->def_sid; 1370 rc = 0; 1371 } else { 1372 rc = security_context_to_sid_default(context, rc, &sid, 1373 sbsec->def_sid, 1374 GFP_NOFS); 1375 if (rc) { 1376 char *dev = inode->i_sb->s_id; 1377 unsigned long ino = inode->i_ino; 1378 1379 if (rc == -EINVAL) { 1380 if (printk_ratelimit()) 1381 printk(KERN_NOTICE "SELinux: inode=%lu on dev=%s was found to have an invalid " 1382 "context=%s. This indicates you may need to relabel the inode or the " 1383 "filesystem in question.\n", ino, dev, context); 1384 } else { 1385 printk(KERN_WARNING "SELinux: %s: context_to_sid(%s) " 1386 "returned %d for dev=%s ino=%ld\n", 1387 __func__, context, -rc, dev, ino); 1388 } 1389 kfree(context); 1390 /* Leave with the unlabeled SID */ 1391 rc = 0; 1392 break; 1393 } 1394 } 1395 kfree(context); 1396 isec->sid = sid; 1397 break; 1398 case SECURITY_FS_USE_TASK: 1399 isec->sid = isec->task_sid; 1400 break; 1401 case SECURITY_FS_USE_TRANS: 1402 /* Default to the fs SID. */ 1403 isec->sid = sbsec->sid; 1404 1405 /* Try to obtain a transition SID. */ 1406 isec->sclass = inode_mode_to_security_class(inode->i_mode); 1407 rc = security_transition_sid(isec->task_sid, sbsec->sid, 1408 isec->sclass, NULL, &sid); 1409 if (rc) 1410 goto out_unlock; 1411 isec->sid = sid; 1412 break; 1413 case SECURITY_FS_USE_MNTPOINT: 1414 isec->sid = sbsec->mntpoint_sid; 1415 break; 1416 default: 1417 /* Default to the fs superblock SID. */ 1418 isec->sid = sbsec->sid; 1419 1420 if ((sbsec->flags & SE_SBPROC) && !S_ISLNK(inode->i_mode)) { 1421 if (opt_dentry) { 1422 isec->sclass = inode_mode_to_security_class(inode->i_mode); 1423 rc = selinux_proc_get_sid(opt_dentry, 1424 isec->sclass, 1425 &sid); 1426 if (rc) 1427 goto out_unlock; 1428 isec->sid = sid; 1429 } 1430 } 1431 break; 1432 } 1433 1434 isec->initialized = 1; 1435 1436out_unlock: 1437 mutex_unlock(&isec->lock); 1438out: 1439 if (isec->sclass == SECCLASS_FILE) 1440 isec->sclass = inode_mode_to_security_class(inode->i_mode); 1441 return rc; 1442} 1443 1444/* Convert a Linux signal to an access vector. */ 1445static inline u32 signal_to_av(int sig) 1446{ 1447 u32 perm = 0; 1448 1449 switch (sig) { 1450 case SIGCHLD: 1451 /* Commonly granted from child to parent. */ 1452 perm = PROCESS__SIGCHLD; 1453 break; 1454 case SIGKILL: 1455 /* Cannot be caught or ignored */ 1456 perm = PROCESS__SIGKILL; 1457 break; 1458 case SIGSTOP: 1459 /* Cannot be caught or ignored */ 1460 perm = PROCESS__SIGSTOP; 1461 break; 1462 default: 1463 /* All other signals. */ 1464 perm = PROCESS__SIGNAL; 1465 break; 1466 } 1467 1468 return perm; 1469} 1470 1471/* 1472 * Check permission between a pair of credentials 1473 * fork check, ptrace check, etc. 1474 */ 1475static int cred_has_perm(const struct cred *actor, 1476 const struct cred *target, 1477 u32 perms) 1478{ 1479 u32 asid = cred_sid(actor), tsid = cred_sid(target); 1480 1481 return avc_has_perm(asid, tsid, SECCLASS_PROCESS, perms, NULL); 1482} 1483 1484/* 1485 * Check permission between a pair of tasks, e.g. signal checks, 1486 * fork check, ptrace check, etc. 1487 * tsk1 is the actor and tsk2 is the target 1488 * - this uses the default subjective creds of tsk1 1489 */ 1490static int task_has_perm(const struct task_struct *tsk1, 1491 const struct task_struct *tsk2, 1492 u32 perms) 1493{ 1494 const struct task_security_struct *__tsec1, *__tsec2; 1495 u32 sid1, sid2; 1496 1497 rcu_read_lock(); 1498 __tsec1 = __task_cred(tsk1)->security; sid1 = __tsec1->sid; 1499 __tsec2 = __task_cred(tsk2)->security; sid2 = __tsec2->sid; 1500 rcu_read_unlock(); 1501 return avc_has_perm(sid1, sid2, SECCLASS_PROCESS, perms, NULL); 1502} 1503 1504/* 1505 * Check permission between current and another task, e.g. signal checks, 1506 * fork check, ptrace check, etc. 1507 * current is the actor and tsk2 is the target 1508 * - this uses current's subjective creds 1509 */ 1510static int current_has_perm(const struct task_struct *tsk, 1511 u32 perms) 1512{ 1513 u32 sid, tsid; 1514 1515 sid = current_sid(); 1516 tsid = task_sid(tsk); 1517 return avc_has_perm(sid, tsid, SECCLASS_PROCESS, perms, NULL); 1518} 1519 1520#if CAP_LAST_CAP > 63 1521#error Fix SELinux to handle capabilities > 63. 1522#endif 1523 1524/* Check whether a task is allowed to use a capability. */ 1525static int cred_has_capability(const struct cred *cred, 1526 int cap, int audit) 1527{ 1528 struct common_audit_data ad; 1529 struct av_decision avd; 1530 u16 sclass; 1531 u32 sid = cred_sid(cred); 1532 u32 av = CAP_TO_MASK(cap); 1533 int rc; 1534 1535 ad.type = LSM_AUDIT_DATA_CAP; 1536 ad.u.cap = cap; 1537 1538 switch (CAP_TO_INDEX(cap)) { 1539 case 0: 1540 sclass = SECCLASS_CAPABILITY; 1541 break; 1542 case 1: 1543 sclass = SECCLASS_CAPABILITY2; 1544 break; 1545 default: 1546 printk(KERN_ERR 1547 "SELinux: out of range capability %d\n", cap); 1548 BUG(); 1549 return -EINVAL; 1550 } 1551 1552 rc = avc_has_perm_noaudit(sid, sid, sclass, av, 0, &avd); 1553 if (audit == SECURITY_CAP_AUDIT) { 1554 int rc2 = avc_audit(sid, sid, sclass, av, &avd, rc, &ad); 1555 if (rc2) 1556 return rc2; 1557 } 1558 return rc; 1559} 1560 1561/* Check whether a task is allowed to use a system operation. */ 1562static int task_has_system(struct task_struct *tsk, 1563 u32 perms) 1564{ 1565 u32 sid = task_sid(tsk); 1566 1567 return avc_has_perm(sid, SECINITSID_KERNEL, 1568 SECCLASS_SYSTEM, perms, NULL); 1569} 1570 1571/* Check whether a task has a particular permission to an inode. 1572 The 'adp' parameter is optional and allows other audit 1573 data to be passed (e.g. the dentry). */ 1574static int inode_has_perm(const struct cred *cred, 1575 struct inode *inode, 1576 u32 perms, 1577 struct common_audit_data *adp) 1578{ 1579 struct inode_security_struct *isec; 1580 u32 sid; 1581 1582 validate_creds(cred); 1583 1584 if (unlikely(IS_PRIVATE(inode))) 1585 return 0; 1586 1587 sid = cred_sid(cred); 1588 isec = inode->i_security; 1589 1590 return avc_has_perm(sid, isec->sid, isec->sclass, perms, adp); 1591} 1592 1593/* Same as inode_has_perm, but pass explicit audit data containing 1594 the dentry to help the auditing code to more easily generate the 1595 pathname if needed. */ 1596static inline int dentry_has_perm(const struct cred *cred, 1597 struct dentry *dentry, 1598 u32 av) 1599{ 1600 struct inode *inode = dentry->d_inode; 1601 struct common_audit_data ad; 1602 1603 ad.type = LSM_AUDIT_DATA_DENTRY; 1604 ad.u.dentry = dentry; 1605 return inode_has_perm(cred, inode, av, &ad); 1606} 1607 1608/* Same as inode_has_perm, but pass explicit audit data containing 1609 the path to help the auditing code to more easily generate the 1610 pathname if needed. */ 1611static inline int path_has_perm(const struct cred *cred, 1612 struct path *path, 1613 u32 av) 1614{ 1615 struct inode *inode = path->dentry->d_inode; 1616 struct common_audit_data ad; 1617 1618 ad.type = LSM_AUDIT_DATA_PATH; 1619 ad.u.path = *path; 1620 return inode_has_perm(cred, inode, av, &ad); 1621} 1622 1623/* Same as path_has_perm, but uses the inode from the file struct. */ 1624static inline int file_path_has_perm(const struct cred *cred, 1625 struct file *file, 1626 u32 av) 1627{ 1628 struct common_audit_data ad; 1629 1630 ad.type = LSM_AUDIT_DATA_PATH; 1631 ad.u.path = file->f_path; 1632 return inode_has_perm(cred, file_inode(file), av, &ad); 1633} 1634 1635/* Check whether a task can use an open file descriptor to 1636 access an inode in a given way. Check access to the 1637 descriptor itself, and then use dentry_has_perm to 1638 check a particular permission to the file. 1639 Access to the descriptor is implicitly granted if it 1640 has the same SID as the process. If av is zero, then 1641 access to the file is not checked, e.g. for cases 1642 where only the descriptor is affected like seek. */ 1643static int file_has_perm(const struct cred *cred, 1644 struct file *file, 1645 u32 av) 1646{ 1647 struct file_security_struct *fsec = file->f_security; 1648 struct inode *inode = file_inode(file); 1649 struct common_audit_data ad; 1650 u32 sid = cred_sid(cred); 1651 int rc; 1652 1653 ad.type = LSM_AUDIT_DATA_PATH; 1654 ad.u.path = file->f_path; 1655 1656 if (sid != fsec->sid) { 1657 rc = avc_has_perm(sid, fsec->sid, 1658 SECCLASS_FD, 1659 FD__USE, 1660 &ad); 1661 if (rc) 1662 goto out; 1663 } 1664 1665 /* av is zero if only checking access to the descriptor. */ 1666 rc = 0; 1667 if (av) 1668 rc = inode_has_perm(cred, inode, av, &ad); 1669 1670out: 1671 return rc; 1672} 1673 1674/* Check whether a task can create a file. */ 1675static int may_create(struct inode *dir, 1676 struct dentry *dentry, 1677 u16 tclass) 1678{ 1679 const struct task_security_struct *tsec = current_security(); 1680 struct inode_security_struct *dsec; 1681 struct superblock_security_struct *sbsec; 1682 u32 sid, newsid; 1683 struct common_audit_data ad; 1684 int rc; 1685 1686 dsec = dir->i_security; 1687 sbsec = dir->i_sb->s_security; 1688 1689 sid = tsec->sid; 1690 newsid = tsec->create_sid; 1691 1692 ad.type = LSM_AUDIT_DATA_DENTRY; 1693 ad.u.dentry = dentry; 1694 1695 rc = avc_has_perm(sid, dsec->sid, SECCLASS_DIR, 1696 DIR__ADD_NAME | DIR__SEARCH, 1697 &ad); 1698 if (rc) 1699 return rc; 1700 1701 if (!newsid || !(sbsec->flags & SBLABEL_MNT)) { 1702 rc = security_transition_sid(sid, dsec->sid, tclass, 1703 &dentry->d_name, &newsid); 1704 if (rc) 1705 return rc; 1706 } 1707 1708 rc = avc_has_perm(sid, newsid, tclass, FILE__CREATE, &ad); 1709 if (rc) 1710 return rc; 1711 1712 return avc_has_perm(newsid, sbsec->sid, 1713 SECCLASS_FILESYSTEM, 1714 FILESYSTEM__ASSOCIATE, &ad); 1715} 1716 1717/* Check whether a task can create a key. */ 1718static int may_create_key(u32 ksid, 1719 struct task_struct *ctx) 1720{ 1721 u32 sid = task_sid(ctx); 1722 1723 return avc_has_perm(sid, ksid, SECCLASS_KEY, KEY__CREATE, NULL); 1724} 1725 1726#define MAY_LINK 0 1727#define MAY_UNLINK 1 1728#define MAY_RMDIR 2 1729 1730/* Check whether a task can link, unlink, or rmdir a file/directory. */ 1731static int may_link(struct inode *dir, 1732 struct dentry *dentry, 1733 int kind) 1734 1735{ 1736 struct inode_security_struct *dsec, *isec; 1737 struct common_audit_data ad; 1738 u32 sid = current_sid(); 1739 u32 av; 1740 int rc; 1741 1742 dsec = dir->i_security; 1743 isec = dentry->d_inode->i_security; 1744 1745 ad.type = LSM_AUDIT_DATA_DENTRY; 1746 ad.u.dentry = dentry; 1747 1748 av = DIR__SEARCH; 1749 av |= (kind ? DIR__REMOVE_NAME : DIR__ADD_NAME); 1750 rc = avc_has_perm(sid, dsec->sid, SECCLASS_DIR, av, &ad); 1751 if (rc) 1752 return rc; 1753 1754 switch (kind) { 1755 case MAY_LINK: 1756 av = FILE__LINK; 1757 break; 1758 case MAY_UNLINK: 1759 av = FILE__UNLINK; 1760 break; 1761 case MAY_RMDIR: 1762 av = DIR__RMDIR; 1763 break; 1764 default: 1765 printk(KERN_WARNING "SELinux: %s: unrecognized kind %d\n", 1766 __func__, kind); 1767 return 0; 1768 } 1769 1770 rc = avc_has_perm(sid, isec->sid, isec->sclass, av, &ad); 1771 return rc; 1772} 1773 1774static inline int may_rename(struct inode *old_dir, 1775 struct dentry *old_dentry, 1776 struct inode *new_dir, 1777 struct dentry *new_dentry) 1778{ 1779 struct inode_security_struct *old_dsec, *new_dsec, *old_isec, *new_isec; 1780 struct common_audit_data ad; 1781 u32 sid = current_sid(); 1782 u32 av; 1783 int old_is_dir, new_is_dir; 1784 int rc; 1785 1786 old_dsec = old_dir->i_security; 1787 old_isec = old_dentry->d_inode->i_security; 1788 old_is_dir = S_ISDIR(old_dentry->d_inode->i_mode); 1789 new_dsec = new_dir->i_security; 1790 1791 ad.type = LSM_AUDIT_DATA_DENTRY; 1792 1793 ad.u.dentry = old_dentry; 1794 rc = avc_has_perm(sid, old_dsec->sid, SECCLASS_DIR, 1795 DIR__REMOVE_NAME | DIR__SEARCH, &ad); 1796 if (rc) 1797 return rc; 1798 rc = avc_has_perm(sid, old_isec->sid, 1799 old_isec->sclass, FILE__RENAME, &ad); 1800 if (rc) 1801 return rc; 1802 if (old_is_dir && new_dir != old_dir) { 1803 rc = avc_has_perm(sid, old_isec->sid, 1804 old_isec->sclass, DIR__REPARENT, &ad); 1805 if (rc) 1806 return rc; 1807 } 1808 1809 ad.u.dentry = new_dentry; 1810 av = DIR__ADD_NAME | DIR__SEARCH; 1811 if (new_dentry->d_inode) 1812 av |= DIR__REMOVE_NAME; 1813 rc = avc_has_perm(sid, new_dsec->sid, SECCLASS_DIR, av, &ad); 1814 if (rc) 1815 return rc; 1816 if (new_dentry->d_inode) { 1817 new_isec = new_dentry->d_inode->i_security; 1818 new_is_dir = S_ISDIR(new_dentry->d_inode->i_mode); 1819 rc = avc_has_perm(sid, new_isec->sid, 1820 new_isec->sclass, 1821 (new_is_dir ? DIR__RMDIR : FILE__UNLINK), &ad); 1822 if (rc) 1823 return rc; 1824 } 1825 1826 return 0; 1827} 1828 1829/* Check whether a task can perform a filesystem operation. */ 1830static int superblock_has_perm(const struct cred *cred, 1831 struct super_block *sb, 1832 u32 perms, 1833 struct common_audit_data *ad) 1834{ 1835 struct superblock_security_struct *sbsec; 1836 u32 sid = cred_sid(cred); 1837 1838 sbsec = sb->s_security; 1839 return avc_has_perm(sid, sbsec->sid, SECCLASS_FILESYSTEM, perms, ad); 1840} 1841 1842/* Convert a Linux mode and permission mask to an access vector. */ 1843static inline u32 file_mask_to_av(int mode, int mask) 1844{ 1845 u32 av = 0; 1846 1847 if (!S_ISDIR(mode)) { 1848 if (mask & MAY_EXEC) 1849 av |= FILE__EXECUTE; 1850 if (mask & MAY_READ) 1851 av |= FILE__READ; 1852 1853 if (mask & MAY_APPEND) 1854 av |= FILE__APPEND; 1855 else if (mask & MAY_WRITE) 1856 av |= FILE__WRITE; 1857 1858 } else { 1859 if (mask & MAY_EXEC) 1860 av |= DIR__SEARCH; 1861 if (mask & MAY_WRITE) 1862 av |= DIR__WRITE; 1863 if (mask & MAY_READ) 1864 av |= DIR__READ; 1865 } 1866 1867 return av; 1868} 1869 1870/* Convert a Linux file to an access vector. */ 1871static inline u32 file_to_av(struct file *file) 1872{ 1873 u32 av = 0; 1874 1875 if (file->f_mode & FMODE_READ) 1876 av |= FILE__READ; 1877 if (file->f_mode & FMODE_WRITE) { 1878 if (file->f_flags & O_APPEND) 1879 av |= FILE__APPEND; 1880 else 1881 av |= FILE__WRITE; 1882 } 1883 if (!av) { 1884 /* 1885 * Special file opened with flags 3 for ioctl-only use. 1886 */ 1887 av = FILE__IOCTL; 1888 } 1889 1890 return av; 1891} 1892 1893/* 1894 * Convert a file to an access vector and include the correct open 1895 * open permission. 1896 */ 1897static inline u32 open_file_to_av(struct file *file) 1898{ 1899 u32 av = file_to_av(file); 1900 1901 if (selinux_policycap_openperm) 1902 av |= FILE__OPEN; 1903 1904 return av; 1905} 1906 1907/* Hook functions begin here. */ 1908 1909static int selinux_ptrace_access_check(struct task_struct *child, 1910 unsigned int mode) 1911{ 1912 int rc; 1913 1914 rc = cap_ptrace_access_check(child, mode); 1915 if (rc) 1916 return rc; 1917 1918 if (mode & PTRACE_MODE_READ) { 1919 u32 sid = current_sid(); 1920 u32 csid = task_sid(child); 1921 return avc_has_perm(sid, csid, SECCLASS_FILE, FILE__READ, NULL); 1922 } 1923 1924 return current_has_perm(child, PROCESS__PTRACE); 1925} 1926 1927static int selinux_ptrace_traceme(struct task_struct *parent) 1928{ 1929 int rc; 1930 1931 rc = cap_ptrace_traceme(parent); 1932 if (rc) 1933 return rc; 1934 1935 return task_has_perm(parent, current, PROCESS__PTRACE); 1936} 1937 1938static int selinux_capget(struct task_struct *target, kernel_cap_t *effective, 1939 kernel_cap_t *inheritable, kernel_cap_t *permitted) 1940{ 1941 int error; 1942 1943 error = current_has_perm(target, PROCESS__GETCAP); 1944 if (error) 1945 return error; 1946 1947 return cap_capget(target, effective, inheritable, permitted); 1948} 1949 1950static int selinux_capset(struct cred *new, const struct cred *old, 1951 const kernel_cap_t *effective, 1952 const kernel_cap_t *inheritable, 1953 const kernel_cap_t *permitted) 1954{ 1955 int error; 1956 1957 error = cap_capset(new, old, 1958 effective, inheritable, permitted); 1959 if (error) 1960 return error; 1961 1962 return cred_has_perm(old, new, PROCESS__SETCAP); 1963} 1964 1965/* 1966 * (This comment used to live with the selinux_task_setuid hook, 1967 * which was removed). 1968 * 1969 * Since setuid only affects the current process, and since the SELinux 1970 * controls are not based on the Linux identity attributes, SELinux does not 1971 * need to control this operation. However, SELinux does control the use of 1972 * the CAP_SETUID and CAP_SETGID capabilities using the capable hook. 1973 */ 1974 1975static int selinux_capable(const struct cred *cred, struct user_namespace *ns, 1976 int cap, int audit) 1977{ 1978 int rc; 1979 1980 rc = cap_capable(cred, ns, cap, audit); 1981 if (rc) 1982 return rc; 1983 1984 return cred_has_capability(cred, cap, audit); 1985} 1986 1987static int selinux_quotactl(int cmds, int type, int id, struct super_block *sb) 1988{ 1989 const struct cred *cred = current_cred(); 1990 int rc = 0; 1991 1992 if (!sb) 1993 return 0; 1994 1995 switch (cmds) { 1996 case Q_SYNC: 1997 case Q_QUOTAON: 1998 case Q_QUOTAOFF: 1999 case Q_SETINFO: 2000 case Q_SETQUOTA: 2001 rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAMOD, NULL); 2002 break; 2003 case Q_GETFMT: 2004 case Q_GETINFO: 2005 case Q_GETQUOTA: 2006 rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAGET, NULL); 2007 break; 2008 default: 2009 rc = 0; /* let the kernel handle invalid cmds */ 2010 break; 2011 } 2012 return rc; 2013} 2014 2015static int selinux_quota_on(struct dentry *dentry) 2016{ 2017 const struct cred *cred = current_cred(); 2018 2019 return dentry_has_perm(cred, dentry, FILE__QUOTAON); 2020} 2021 2022static int selinux_syslog(int type) 2023{ 2024 int rc; 2025 2026 switch (type) { 2027 case SYSLOG_ACTION_READ_ALL: /* Read last kernel messages */ 2028 case SYSLOG_ACTION_SIZE_BUFFER: /* Return size of the log buffer */ 2029 rc = task_has_system(current, SYSTEM__SYSLOG_READ); 2030 break; 2031 case SYSLOG_ACTION_CONSOLE_OFF: /* Disable logging to console */ 2032 case SYSLOG_ACTION_CONSOLE_ON: /* Enable logging to console */ 2033 /* Set level of messages printed to console */ 2034 case SYSLOG_ACTION_CONSOLE_LEVEL: 2035 rc = task_has_system(current, SYSTEM__SYSLOG_CONSOLE); 2036 break; 2037 case SYSLOG_ACTION_CLOSE: /* Close log */ 2038 case SYSLOG_ACTION_OPEN: /* Open log */ 2039 case SYSLOG_ACTION_READ: /* Read from log */ 2040 case SYSLOG_ACTION_READ_CLEAR: /* Read/clear last kernel messages */ 2041 case SYSLOG_ACTION_CLEAR: /* Clear ring buffer */ 2042 default: 2043 rc = task_has_system(current, SYSTEM__SYSLOG_MOD); 2044 break; 2045 } 2046 return rc; 2047} 2048 2049/* 2050 * Check that a process has enough memory to allocate a new virtual 2051 * mapping. 0 means there is enough memory for the allocation to 2052 * succeed and -ENOMEM implies there is not. 2053 * 2054 * Do not audit the selinux permission check, as this is applied to all 2055 * processes that allocate mappings. 2056 */ 2057static int selinux_vm_enough_memory(struct mm_struct *mm, long pages) 2058{ 2059 int rc, cap_sys_admin = 0; 2060 2061 rc = selinux_capable(current_cred(), &init_user_ns, CAP_SYS_ADMIN, 2062 SECURITY_CAP_NOAUDIT); 2063 if (rc == 0) 2064 cap_sys_admin = 1; 2065 2066 return __vm_enough_memory(mm, pages, cap_sys_admin); 2067} 2068 2069/* binprm security operations */ 2070 2071static int selinux_bprm_set_creds(struct linux_binprm *bprm) 2072{ 2073 const struct task_security_struct *old_tsec; 2074 struct task_security_struct *new_tsec; 2075 struct inode_security_struct *isec; 2076 struct common_audit_data ad; 2077 struct inode *inode = file_inode(bprm->file); 2078 int rc; 2079 2080 rc = cap_bprm_set_creds(bprm); 2081 if (rc) 2082 return rc; 2083 2084 /* SELinux context only depends on initial program or script and not 2085 * the script interpreter */ 2086 if (bprm->cred_prepared) 2087 return 0; 2088 2089 old_tsec = current_security(); 2090 new_tsec = bprm->cred->security; 2091 isec = inode->i_security; 2092 2093 /* Default to the current task SID. */ 2094 new_tsec->sid = old_tsec->sid; 2095 new_tsec->osid = old_tsec->sid; 2096 2097 /* Reset fs, key, and sock SIDs on execve. */ 2098 new_tsec->create_sid = 0; 2099 new_tsec->keycreate_sid = 0; 2100 new_tsec->sockcreate_sid = 0; 2101 2102 if (old_tsec->exec_sid) { 2103 new_tsec->sid = old_tsec->exec_sid; 2104 /* Reset exec SID on execve. */ 2105 new_tsec->exec_sid = 0; 2106 2107 /* 2108 * Minimize confusion: if no_new_privs and a transition is 2109 * explicitly requested, then fail the exec. 2110 */ 2111 if (bprm->unsafe & LSM_UNSAFE_NO_NEW_PRIVS) 2112 return -EPERM; 2113 } else { 2114 /* Check for a default transition on this program. */ 2115 rc = security_transition_sid(old_tsec->sid, isec->sid, 2116 SECCLASS_PROCESS, NULL, 2117 &new_tsec->sid); 2118 if (rc) 2119 return rc; 2120 } 2121 2122 ad.type = LSM_AUDIT_DATA_PATH; 2123 ad.u.path = bprm->file->f_path; 2124 2125 if ((bprm->file->f_path.mnt->mnt_flags & MNT_NOSUID) || 2126 (bprm->unsafe & LSM_UNSAFE_NO_NEW_PRIVS)) 2127 new_tsec->sid = old_tsec->sid; 2128 2129 if (new_tsec->sid == old_tsec->sid) { 2130 rc = avc_has_perm(old_tsec->sid, isec->sid, 2131 SECCLASS_FILE, FILE__EXECUTE_NO_TRANS, &ad); 2132 if (rc) 2133 return rc; 2134 } else { 2135 /* Check permissions for the transition. */ 2136 rc = avc_has_perm(old_tsec->sid, new_tsec->sid, 2137 SECCLASS_PROCESS, PROCESS__TRANSITION, &ad); 2138 if (rc) 2139 return rc; 2140 2141 rc = avc_has_perm(new_tsec->sid, isec->sid, 2142 SECCLASS_FILE, FILE__ENTRYPOINT, &ad); 2143 if (rc) 2144 return rc; 2145 2146 /* Check for shared state */ 2147 if (bprm->unsafe & LSM_UNSAFE_SHARE) { 2148 rc = avc_has_perm(old_tsec->sid, new_tsec->sid, 2149 SECCLASS_PROCESS, PROCESS__SHARE, 2150 NULL); 2151 if (rc) 2152 return -EPERM; 2153 } 2154 2155 /* Make sure that anyone attempting to ptrace over a task that 2156 * changes its SID has the appropriate permit */ 2157 if (bprm->unsafe & 2158 (LSM_UNSAFE_PTRACE | LSM_UNSAFE_PTRACE_CAP)) { 2159 struct task_struct *tracer; 2160 struct task_security_struct *sec; 2161 u32 ptsid = 0; 2162 2163 rcu_read_lock(); 2164 tracer = ptrace_parent(current); 2165 if (likely(tracer != NULL)) { 2166 sec = __task_cred(tracer)->security; 2167 ptsid = sec->sid; 2168 } 2169 rcu_read_unlock(); 2170 2171 if (ptsid != 0) { 2172 rc = avc_has_perm(ptsid, new_tsec->sid, 2173 SECCLASS_PROCESS, 2174 PROCESS__PTRACE, NULL); 2175 if (rc) 2176 return -EPERM; 2177 } 2178 } 2179 2180 /* Clear any possibly unsafe personality bits on exec: */ 2181 bprm->per_clear |= PER_CLEAR_ON_SETID; 2182 } 2183 2184 return 0; 2185} 2186 2187static int selinux_bprm_secureexec(struct linux_binprm *bprm) 2188{ 2189 const struct task_security_struct *tsec = current_security(); 2190 u32 sid, osid; 2191 int atsecure = 0; 2192 2193 sid = tsec->sid; 2194 osid = tsec->osid; 2195 2196 if (osid != sid) { 2197 /* Enable secure mode for SIDs transitions unless 2198 the noatsecure permission is granted between 2199 the two SIDs, i.e. ahp returns 0. */ 2200 atsecure = avc_has_perm(osid, sid, 2201 SECCLASS_PROCESS, 2202 PROCESS__NOATSECURE, NULL); 2203 } 2204 2205 return (atsecure || cap_bprm_secureexec(bprm)); 2206} 2207 2208static int match_file(const void *p, struct file *file, unsigned fd) 2209{ 2210 return file_has_perm(p, file, file_to_av(file)) ? fd + 1 : 0; 2211} 2212 2213/* Derived from fs/exec.c:flush_old_files. */ 2214static inline void flush_unauthorized_files(const struct cred *cred, 2215 struct files_struct *files) 2216{ 2217 struct file *file, *devnull = NULL; 2218 struct tty_struct *tty; 2219 int drop_tty = 0; 2220 unsigned n; 2221 2222 tty = get_current_tty(); 2223 if (tty) { 2224 spin_lock(&tty_files_lock); 2225 if (!list_empty(&tty->tty_files)) { 2226 struct tty_file_private *file_priv; 2227 2228 /* Revalidate access to controlling tty. 2229 Use file_path_has_perm on the tty path directly 2230 rather than using file_has_perm, as this particular 2231 open file may belong to another process and we are 2232 only interested in the inode-based check here. */ 2233 file_priv = list_first_entry(&tty->tty_files, 2234 struct tty_file_private, list); 2235 file = file_priv->file; 2236 if (file_path_has_perm(cred, file, FILE__READ | FILE__WRITE)) 2237 drop_tty = 1; 2238 } 2239 spin_unlock(&tty_files_lock); 2240 tty_kref_put(tty); 2241 } 2242 /* Reset controlling tty. */ 2243 if (drop_tty) 2244 no_tty(); 2245 2246 /* Revalidate access to inherited open files. */ 2247 n = iterate_fd(files, 0, match_file, cred); 2248 if (!n) /* none found? */ 2249 return; 2250 2251 devnull = dentry_open(&selinux_null, O_RDWR, cred); 2252 if (IS_ERR(devnull)) 2253 devnull = NULL; 2254 /* replace all the matching ones with this */ 2255 do { 2256 replace_fd(n - 1, devnull, 0); 2257 } while ((n = iterate_fd(files, n, match_file, cred)) != 0); 2258 if (devnull) 2259 fput(devnull); 2260} 2261 2262/* 2263 * Prepare a process for imminent new credential changes due to exec 2264 */ 2265static void selinux_bprm_committing_creds(struct linux_binprm *bprm) 2266{ 2267 struct task_security_struct *new_tsec; 2268 struct rlimit *rlim, *initrlim; 2269 int rc, i; 2270 2271 new_tsec = bprm->cred->security; 2272 if (new_tsec->sid == new_tsec->osid) 2273 return; 2274 2275 /* Close files for which the new task SID is not authorized. */ 2276 flush_unauthorized_files(bprm->cred, current->files); 2277 2278 /* Always clear parent death signal on SID transitions. */ 2279 current->pdeath_signal = 0; 2280 2281 /* Check whether the new SID can inherit resource limits from the old 2282 * SID. If not, reset all soft limits to the lower of the current 2283 * task's hard limit and the init task's soft limit. 2284 * 2285 * Note that the setting of hard limits (even to lower them) can be 2286 * controlled by the setrlimit check. The inclusion of the init task's 2287 * soft limit into the computation is to avoid resetting soft limits 2288 * higher than the default soft limit for cases where the default is 2289 * lower than the hard limit, e.g. RLIMIT_CORE or RLIMIT_STACK. 2290 */ 2291 rc = avc_has_perm(new_tsec->osid, new_tsec->sid, SECCLASS_PROCESS, 2292 PROCESS__RLIMITINH, NULL); 2293 if (rc) { 2294 /* protect against do_prlimit() */ 2295 task_lock(current); 2296 for (i = 0; i < RLIM_NLIMITS; i++) { 2297 rlim = current->signal->rlim + i; 2298 initrlim = init_task.signal->rlim + i; 2299 rlim->rlim_cur = min(rlim->rlim_max, initrlim->rlim_cur); 2300 } 2301 task_unlock(current); 2302 update_rlimit_cpu(current, rlimit(RLIMIT_CPU)); 2303 } 2304} 2305 2306/* 2307 * Clean up the process immediately after the installation of new credentials 2308 * due to exec 2309 */ 2310static void selinux_bprm_committed_creds(struct linux_binprm *bprm) 2311{ 2312 const struct task_security_struct *tsec = current_security(); 2313 struct itimerval itimer; 2314 u32 osid, sid; 2315 int rc, i; 2316 2317 osid = tsec->osid; 2318 sid = tsec->sid; 2319 2320 if (sid == osid) 2321 return; 2322 2323 /* Check whether the new SID can inherit signal state from the old SID. 2324 * If not, clear itimers to avoid subsequent signal generation and 2325 * flush and unblock signals. 2326 * 2327 * This must occur _after_ the task SID has been updated so that any 2328 * kill done after the flush will be checked against the new SID. 2329 */ 2330 rc = avc_has_perm(osid, sid, SECCLASS_PROCESS, PROCESS__SIGINH, NULL); 2331 if (rc) { 2332 memset(&itimer, 0, sizeof itimer); 2333 for (i = 0; i < 3; i++) 2334 do_setitimer(i, &itimer, NULL); 2335 spin_lock_irq(&current->sighand->siglock); 2336 if (!(current->signal->flags & SIGNAL_GROUP_EXIT)) { 2337 __flush_signals(current); 2338 flush_signal_handlers(current, 1); 2339 sigemptyset(&current->blocked); 2340 } 2341 spin_unlock_irq(&current->sighand->siglock); 2342 } 2343 2344 /* Wake up the parent if it is waiting so that it can recheck 2345 * wait permission to the new task SID. */ 2346 read_lock(&tasklist_lock); 2347 __wake_up_parent(current, current->real_parent); 2348 read_unlock(&tasklist_lock); 2349} 2350 2351/* superblock security operations */ 2352 2353static int selinux_sb_alloc_security(struct super_block *sb) 2354{ 2355 return superblock_alloc_security(sb); 2356} 2357 2358static void selinux_sb_free_security(struct super_block *sb) 2359{ 2360 superblock_free_security(sb); 2361} 2362 2363static inline int match_prefix(char *prefix, int plen, char *option, int olen) 2364{ 2365 if (plen > olen) 2366 return 0; 2367 2368 return !memcmp(prefix, option, plen); 2369} 2370 2371static inline int selinux_option(char *option, int len) 2372{ 2373 return (match_prefix(CONTEXT_STR, sizeof(CONTEXT_STR)-1, option, len) || 2374 match_prefix(FSCONTEXT_STR, sizeof(FSCONTEXT_STR)-1, option, len) || 2375 match_prefix(DEFCONTEXT_STR, sizeof(DEFCONTEXT_STR)-1, option, len) || 2376 match_prefix(ROOTCONTEXT_STR, sizeof(ROOTCONTEXT_STR)-1, option, len) || 2377 match_prefix(LABELSUPP_STR, sizeof(LABELSUPP_STR)-1, option, len)); 2378} 2379 2380static inline void take_option(char **to, char *from, int *first, int len) 2381{ 2382 if (!*first) { 2383 **to = ','; 2384 *to += 1; 2385 } else 2386 *first = 0; 2387 memcpy(*to, from, len); 2388 *to += len; 2389} 2390 2391static inline void take_selinux_option(char **to, char *from, int *first, 2392 int len) 2393{ 2394 int current_size = 0; 2395 2396 if (!*first) { 2397 **to = '|'; 2398 *to += 1; 2399 } else 2400 *first = 0; 2401 2402 while (current_size < len) { 2403 if (*from != '"') { 2404 **to = *from; 2405 *to += 1; 2406 } 2407 from += 1; 2408 current_size += 1; 2409 } 2410} 2411 2412static int selinux_sb_copy_data(char *orig, char *copy) 2413{ 2414 int fnosec, fsec, rc = 0; 2415 char *in_save, *in_curr, *in_end; 2416 char *sec_curr, *nosec_save, *nosec; 2417 int open_quote = 0; 2418 2419 in_curr = orig; 2420 sec_curr = copy; 2421 2422 nosec = (char *)get_zeroed_page(GFP_KERNEL); 2423 if (!nosec) { 2424 rc = -ENOMEM; 2425 goto out; 2426 } 2427 2428 nosec_save = nosec; 2429 fnosec = fsec = 1; 2430 in_save = in_end = orig; 2431 2432 do { 2433 if (*in_end == '"') 2434 open_quote = !open_quote; 2435 if ((*in_end == ',' && open_quote == 0) || 2436 *in_end == '\0') { 2437 int len = in_end - in_curr; 2438 2439 if (selinux_option(in_curr, len)) 2440 take_selinux_option(&sec_curr, in_curr, &fsec, len); 2441 else 2442 take_option(&nosec, in_curr, &fnosec, len); 2443 2444 in_curr = in_end + 1; 2445 } 2446 } while (*in_end++); 2447 2448 strcpy(in_save, nosec_save); 2449 free_page((unsigned long)nosec_save); 2450out: 2451 return rc; 2452} 2453 2454static int selinux_sb_remount(struct super_block *sb, void *data) 2455{ 2456 int rc, i, *flags; 2457 struct security_mnt_opts opts; 2458 char *secdata, **mount_options; 2459 struct superblock_security_struct *sbsec = sb->s_security; 2460 2461 if (!(sbsec->flags & SE_SBINITIALIZED)) 2462 return 0; 2463 2464 if (!data) 2465 return 0; 2466 2467 if (sb->s_type->fs_flags & FS_BINARY_MOUNTDATA) 2468 return 0; 2469 2470 security_init_mnt_opts(&opts); 2471 secdata = alloc_secdata(); 2472 if (!secdata) 2473 return -ENOMEM; 2474 rc = selinux_sb_copy_data(data, secdata); 2475 if (rc) 2476 goto out_free_secdata; 2477 2478 rc = selinux_parse_opts_str(secdata, &opts); 2479 if (rc) 2480 goto out_free_secdata; 2481 2482 mount_options = opts.mnt_opts; 2483 flags = opts.mnt_opts_flags; 2484 2485 for (i = 0; i < opts.num_mnt_opts; i++) { 2486 u32 sid; 2487 size_t len; 2488 2489 if (flags[i] == SBLABEL_MNT) 2490 continue; 2491 len = strlen(mount_options[i]); 2492 rc = security_context_to_sid(mount_options[i], len, &sid, 2493 GFP_KERNEL); 2494 if (rc) { 2495 printk(KERN_WARNING "SELinux: security_context_to_sid" 2496 "(%s) failed for (dev %s, type %s) errno=%d\n", 2497 mount_options[i], sb->s_id, sb->s_type->name, rc); 2498 goto out_free_opts; 2499 } 2500 rc = -EINVAL; 2501 switch (flags[i]) { 2502 case FSCONTEXT_MNT: 2503 if (bad_option(sbsec, FSCONTEXT_MNT, sbsec->sid, sid)) 2504 goto out_bad_option; 2505 break; 2506 case CONTEXT_MNT: 2507 if (bad_option(sbsec, CONTEXT_MNT, sbsec->mntpoint_sid, sid)) 2508 goto out_bad_option; 2509 break; 2510 case ROOTCONTEXT_MNT: { 2511 struct inode_security_struct *root_isec; 2512 root_isec = sb->s_root->d_inode->i_security; 2513 2514 if (bad_option(sbsec, ROOTCONTEXT_MNT, root_isec->sid, sid)) 2515 goto out_bad_option; 2516 break; 2517 } 2518 case DEFCONTEXT_MNT: 2519 if (bad_option(sbsec, DEFCONTEXT_MNT, sbsec->def_sid, sid)) 2520 goto out_bad_option; 2521 break; 2522 default: 2523 goto out_free_opts; 2524 } 2525 } 2526 2527 rc = 0; 2528out_free_opts: 2529 security_free_mnt_opts(&opts); 2530out_free_secdata: 2531 free_secdata(secdata); 2532 return rc; 2533out_bad_option: 2534 printk(KERN_WARNING "SELinux: unable to change security options " 2535 "during remount (dev %s, type=%s)\n", sb->s_id, 2536 sb->s_type->name); 2537 goto out_free_opts; 2538} 2539 2540static int selinux_sb_kern_mount(struct super_block *sb, int flags, void *data) 2541{ 2542 const struct cred *cred = current_cred(); 2543 struct common_audit_data ad; 2544 int rc; 2545 2546 rc = superblock_doinit(sb, data); 2547 if (rc) 2548 return rc; 2549 2550 /* Allow all mounts performed by the kernel */ 2551 if (flags & MS_KERNMOUNT) 2552 return 0; 2553 2554 ad.type = LSM_AUDIT_DATA_DENTRY; 2555 ad.u.dentry = sb->s_root; 2556 return superblock_has_perm(cred, sb, FILESYSTEM__MOUNT, &ad); 2557} 2558 2559static int selinux_sb_statfs(struct dentry *dentry) 2560{ 2561 const struct cred *cred = current_cred(); 2562 struct common_audit_data ad; 2563 2564 ad.type = LSM_AUDIT_DATA_DENTRY; 2565 ad.u.dentry = dentry->d_sb->s_root; 2566 return superblock_has_perm(cred, dentry->d_sb, FILESYSTEM__GETATTR, &ad); 2567} 2568 2569static int selinux_mount(const char *dev_name, 2570 struct path *path, 2571 const char *type, 2572 unsigned long flags, 2573 void *data) 2574{ 2575 const struct cred *cred = current_cred(); 2576 2577 if (flags & MS_REMOUNT) 2578 return superblock_has_perm(cred, path->dentry->d_sb, 2579 FILESYSTEM__REMOUNT, NULL); 2580 else 2581 return path_has_perm(cred, path, FILE__MOUNTON); 2582} 2583 2584static int selinux_umount(struct vfsmount *mnt, int flags) 2585{ 2586 const struct cred *cred = current_cred(); 2587 2588 return superblock_has_perm(cred, mnt->mnt_sb, 2589 FILESYSTEM__UNMOUNT, NULL); 2590} 2591 2592/* inode security operations */ 2593 2594static int selinux_inode_alloc_security(struct inode *inode) 2595{ 2596 return inode_alloc_security(inode); 2597} 2598 2599static void selinux_inode_free_security(struct inode *inode) 2600{ 2601 inode_free_security(inode); 2602} 2603 2604static int selinux_dentry_init_security(struct dentry *dentry, int mode, 2605 struct qstr *name, void **ctx, 2606 u32 *ctxlen) 2607{ 2608 const struct cred *cred = current_cred(); 2609 struct task_security_struct *tsec; 2610 struct inode_security_struct *dsec; 2611 struct superblock_security_struct *sbsec; 2612 struct inode *dir = dentry->d_parent->d_inode; 2613 u32 newsid; 2614 int rc; 2615 2616 tsec = cred->security; 2617 dsec = dir->i_security; 2618 sbsec = dir->i_sb->s_security; 2619 2620 if (tsec->create_sid && sbsec->behavior != SECURITY_FS_USE_MNTPOINT) { 2621 newsid = tsec->create_sid; 2622 } else { 2623 rc = security_transition_sid(tsec->sid, dsec->sid, 2624 inode_mode_to_security_class(mode), 2625 name, 2626 &newsid); 2627 if (rc) { 2628 printk(KERN_WARNING 2629 "%s: security_transition_sid failed, rc=%d\n", 2630 __func__, -rc); 2631 return rc; 2632 } 2633 } 2634 2635 return security_sid_to_context(newsid, (char **)ctx, ctxlen); 2636} 2637 2638static int selinux_inode_init_security(struct inode *inode, struct inode *dir, 2639 const struct qstr *qstr, 2640 const char **name, 2641 void **value, size_t *len) 2642{ 2643 const struct task_security_struct *tsec = current_security(); 2644 struct inode_security_struct *dsec; 2645 struct superblock_security_struct *sbsec; 2646 u32 sid, newsid, clen; 2647 int rc; 2648 char *context; 2649 2650 dsec = dir->i_security; 2651 sbsec = dir->i_sb->s_security; 2652 2653 sid = tsec->sid; 2654 newsid = tsec->create_sid; 2655 2656 if ((sbsec->flags & SE_SBINITIALIZED) && 2657 (sbsec->behavior == SECURITY_FS_USE_MNTPOINT)) 2658 newsid = sbsec->mntpoint_sid; 2659 else if (!newsid || !(sbsec->flags & SBLABEL_MNT)) { 2660 rc = security_transition_sid(sid, dsec->sid, 2661 inode_mode_to_security_class(inode->i_mode), 2662 qstr, &newsid); 2663 if (rc) { 2664 printk(KERN_WARNING "%s: " 2665 "security_transition_sid failed, rc=%d (dev=%s " 2666 "ino=%ld)\n", 2667 __func__, 2668 -rc, inode->i_sb->s_id, inode->i_ino); 2669 return rc; 2670 } 2671 } 2672 2673 /* Possibly defer initialization to selinux_complete_init. */ 2674 if (sbsec->flags & SE_SBINITIALIZED) { 2675 struct inode_security_struct *isec = inode->i_security; 2676 isec->sclass = inode_mode_to_security_class(inode->i_mode); 2677 isec->sid = newsid; 2678 isec->initialized = 1; 2679 } 2680 2681 if (!ss_initialized || !(sbsec->flags & SBLABEL_MNT)) 2682 return -EOPNOTSUPP; 2683 2684 if (name) 2685 *name = XATTR_SELINUX_SUFFIX; 2686 2687 if (value && len) { 2688 rc = security_sid_to_context_force(newsid, &context, &clen); 2689 if (rc) 2690 return rc; 2691 *value = context; 2692 *len = clen; 2693 } 2694 2695 return 0; 2696} 2697 2698static int selinux_inode_create(struct inode *dir, struct dentry *dentry, umode_t mode) 2699{ 2700 return may_create(dir, dentry, SECCLASS_FILE); 2701} 2702 2703static int selinux_inode_link(struct dentry *old_dentry, struct inode *dir, struct dentry *new_dentry) 2704{ 2705 return may_link(dir, old_dentry, MAY_LINK); 2706} 2707 2708static int selinux_inode_unlink(struct inode *dir, struct dentry *dentry) 2709{ 2710 return may_link(dir, dentry, MAY_UNLINK); 2711} 2712 2713static int selinux_inode_symlink(struct inode *dir, struct dentry *dentry, const char *name) 2714{ 2715 return may_create(dir, dentry, SECCLASS_LNK_FILE); 2716} 2717 2718static int selinux_inode_mkdir(struct inode *dir, struct dentry *dentry, umode_t mask) 2719{ 2720 return may_create(dir, dentry, SECCLASS_DIR); 2721} 2722 2723static int selinux_inode_rmdir(struct inode *dir, struct dentry *dentry) 2724{ 2725 return may_link(dir, dentry, MAY_RMDIR); 2726} 2727 2728static int selinux_inode_mknod(struct inode *dir, struct dentry *dentry, umode_t mode, dev_t dev) 2729{ 2730 return may_create(dir, dentry, inode_mode_to_security_class(mode)); 2731} 2732 2733static int selinux_inode_rename(struct inode *old_inode, struct dentry *old_dentry, 2734 struct inode *new_inode, struct dentry *new_dentry) 2735{ 2736 return may_rename(old_inode, old_dentry, new_inode, new_dentry); 2737} 2738 2739static int selinux_inode_readlink(struct dentry *dentry) 2740{ 2741 const struct cred *cred = current_cred(); 2742 2743 return dentry_has_perm(cred, dentry, FILE__READ); 2744} 2745 2746static int selinux_inode_follow_link(struct dentry *dentry, struct nameidata *nameidata) 2747{ 2748 const struct cred *cred = current_cred(); 2749 2750 return dentry_has_perm(cred, dentry, FILE__READ); 2751} 2752 2753static noinline int audit_inode_permission(struct inode *inode, 2754 u32 perms, u32 audited, u32 denied, 2755 unsigned flags) 2756{ 2757 struct common_audit_data ad; 2758 struct inode_security_struct *isec = inode->i_security; 2759 int rc; 2760 2761 ad.type = LSM_AUDIT_DATA_INODE; 2762 ad.u.inode = inode; 2763 2764 rc = slow_avc_audit(current_sid(), isec->sid, isec->sclass, perms, 2765 audited, denied, &ad, flags); 2766 if (rc) 2767 return rc; 2768 return 0; 2769} 2770 2771static int selinux_inode_permission(struct inode *inode, int mask) 2772{ 2773 const struct cred *cred = current_cred(); 2774 u32 perms; 2775 bool from_access; 2776 unsigned flags = mask & MAY_NOT_BLOCK; 2777 struct inode_security_struct *isec; 2778 u32 sid; 2779 struct av_decision avd; 2780 int rc, rc2; 2781 u32 audited, denied; 2782 2783 from_access = mask & MAY_ACCESS; 2784 mask &= (MAY_READ|MAY_WRITE|MAY_EXEC|MAY_APPEND); 2785 2786 /* No permission to check. Existence test. */ 2787 if (!mask) 2788 return 0; 2789 2790 validate_creds(cred); 2791 2792 if (unlikely(IS_PRIVATE(inode))) 2793 return 0; 2794 2795 perms = file_mask_to_av(inode->i_mode, mask); 2796 2797 sid = cred_sid(cred); 2798 isec = inode->i_security; 2799 2800 rc = avc_has_perm_noaudit(sid, isec->sid, isec->sclass, perms, 0, &avd); 2801 audited = avc_audit_required(perms, &avd, rc, 2802 from_access ? FILE__AUDIT_ACCESS : 0, 2803 &denied); 2804 if (likely(!audited)) 2805 return rc; 2806 2807 rc2 = audit_inode_permission(inode, perms, audited, denied, flags); 2808 if (rc2) 2809 return rc2; 2810 return rc; 2811} 2812 2813static int selinux_inode_setattr(struct dentry *dentry, struct iattr *iattr) 2814{ 2815 const struct cred *cred = current_cred(); 2816 unsigned int ia_valid = iattr->ia_valid; 2817 __u32 av = FILE__WRITE; 2818 2819 /* ATTR_FORCE is just used for ATTR_KILL_S[UG]ID. */ 2820 if (ia_valid & ATTR_FORCE) { 2821 ia_valid &= ~(ATTR_KILL_SUID | ATTR_KILL_SGID | ATTR_MODE | 2822 ATTR_FORCE); 2823 if (!ia_valid) 2824 return 0; 2825 } 2826 2827 if (ia_valid & (ATTR_MODE | ATTR_UID | ATTR_GID | 2828 ATTR_ATIME_SET | ATTR_MTIME_SET | ATTR_TIMES_SET)) 2829 return dentry_has_perm(cred, dentry, FILE__SETATTR); 2830 2831 if (selinux_policycap_openperm && (ia_valid & ATTR_SIZE)) 2832 av |= FILE__OPEN; 2833 2834 return dentry_has_perm(cred, dentry, av); 2835} 2836 2837static int selinux_inode_getattr(struct vfsmount *mnt, struct dentry *dentry) 2838{ 2839 const struct cred *cred = current_cred(); 2840 struct path path; 2841 2842 path.dentry = dentry; 2843 path.mnt = mnt; 2844 2845 return path_has_perm(cred, &path, FILE__GETATTR); 2846} 2847 2848static int selinux_inode_setotherxattr(struct dentry *dentry, const char *name) 2849{ 2850 const struct cred *cred = current_cred(); 2851 2852 if (!strncmp(name, XATTR_SECURITY_PREFIX, 2853 sizeof XATTR_SECURITY_PREFIX - 1)) { 2854 if (!strcmp(name, XATTR_NAME_CAPS)) { 2855 if (!capable(CAP_SETFCAP)) 2856 return -EPERM; 2857 } else if (!capable(CAP_SYS_ADMIN)) { 2858 /* A different attribute in the security namespace. 2859 Restrict to administrator. */ 2860 return -EPERM; 2861 } 2862 } 2863 2864 /* Not an attribute we recognize, so just check the 2865 ordinary setattr permission. */ 2866 return dentry_has_perm(cred, dentry, FILE__SETATTR); 2867} 2868 2869static int selinux_inode_setxattr(struct dentry *dentry, const char *name, 2870 const void *value, size_t size, int flags) 2871{ 2872 struct inode *inode = dentry->d_inode; 2873 struct inode_security_struct *isec = inode->i_security; 2874 struct superblock_security_struct *sbsec; 2875 struct common_audit_data ad; 2876 u32 newsid, sid = current_sid(); 2877 int rc = 0; 2878 2879 if (strcmp(name, XATTR_NAME_SELINUX)) 2880 return selinux_inode_setotherxattr(dentry, name); 2881 2882 sbsec = inode->i_sb->s_security; 2883 if (!(sbsec->flags & SBLABEL_MNT)) 2884 return -EOPNOTSUPP; 2885 2886 if (!inode_owner_or_capable(inode)) 2887 return -EPERM; 2888 2889 ad.type = LSM_AUDIT_DATA_DENTRY; 2890 ad.u.dentry = dentry; 2891 2892 rc = avc_has_perm(sid, isec->sid, isec->sclass, 2893 FILE__RELABELFROM, &ad); 2894 if (rc) 2895 return rc; 2896 2897 rc = security_context_to_sid(value, size, &newsid, GFP_KERNEL); 2898 if (rc == -EINVAL) { 2899 if (!capable(CAP_MAC_ADMIN)) { 2900 struct audit_buffer *ab; 2901 size_t audit_size; 2902 const char *str; 2903 2904 /* We strip a nul only if it is at the end, otherwise the 2905 * context contains a nul and we should audit that */ 2906 if (value) { 2907 str = value; 2908 if (str[size - 1] == '\0') 2909 audit_size = size - 1; 2910 else 2911 audit_size = size; 2912 } else { 2913 str = ""; 2914 audit_size = 0; 2915 } 2916 ab = audit_log_start(current->audit_context, GFP_ATOMIC, AUDIT_SELINUX_ERR); 2917 audit_log_format(ab, "op=setxattr invalid_context="); 2918 audit_log_n_untrustedstring(ab, value, audit_size); 2919 audit_log_end(ab); 2920 2921 return rc; 2922 } 2923 rc = security_context_to_sid_force(value, size, &newsid); 2924 } 2925 if (rc) 2926 return rc; 2927 2928 rc = avc_has_perm(sid, newsid, isec->sclass, 2929 FILE__RELABELTO, &ad); 2930 if (rc) 2931 return rc; 2932 2933 rc = security_validate_transition(isec->sid, newsid, sid, 2934 isec->sclass); 2935 if (rc) 2936 return rc; 2937 2938 return avc_has_perm(newsid, 2939 sbsec->sid, 2940 SECCLASS_FILESYSTEM, 2941 FILESYSTEM__ASSOCIATE, 2942 &ad); 2943} 2944 2945static void selinux_inode_post_setxattr(struct dentry *dentry, const char *name, 2946 const void *value, size_t size, 2947 int flags) 2948{ 2949 struct inode *inode = dentry->d_inode; 2950 struct inode_security_struct *isec = inode->i_security; 2951 u32 newsid; 2952 int rc; 2953 2954 if (strcmp(name, XATTR_NAME_SELINUX)) { 2955 /* Not an attribute we recognize, so nothing to do. */ 2956 return; 2957 } 2958 2959 rc = security_context_to_sid_force(value, size, &newsid); 2960 if (rc) { 2961 printk(KERN_ERR "SELinux: unable to map context to SID" 2962 "for (%s, %lu), rc=%d\n", 2963 inode->i_sb->s_id, inode->i_ino, -rc); 2964 return; 2965 } 2966 2967 isec->sclass = inode_mode_to_security_class(inode->i_mode); 2968 isec->sid = newsid; 2969 isec->initialized = 1; 2970 2971 return; 2972} 2973 2974static int selinux_inode_getxattr(struct dentry *dentry, const char *name) 2975{ 2976 const struct cred *cred = current_cred(); 2977 2978 return dentry_has_perm(cred, dentry, FILE__GETATTR); 2979} 2980 2981static int selinux_inode_listxattr(struct dentry *dentry) 2982{ 2983 const struct cred *cred = current_cred(); 2984 2985 return dentry_has_perm(cred, dentry, FILE__GETATTR); 2986} 2987 2988static int selinux_inode_removexattr(struct dentry *dentry, const char *name) 2989{ 2990 if (strcmp(name, XATTR_NAME_SELINUX)) 2991 return selinux_inode_setotherxattr(dentry, name); 2992 2993 /* No one is allowed to remove a SELinux security label. 2994 You can change the label, but all data must be labeled. */ 2995 return -EACCES; 2996} 2997 2998/* 2999 * Copy the inode security context value to the user. 3000 * 3001 * Permission check is handled by selinux_inode_getxattr hook. 3002 */ 3003static int selinux_inode_getsecurity(const struct inode *inode, const char *name, void **buffer, bool alloc) 3004{ 3005 u32 size; 3006 int error; 3007 char *context = NULL; 3008 struct inode_security_struct *isec = inode->i_security; 3009 3010 if (strcmp(name, XATTR_SELINUX_SUFFIX)) 3011 return -EOPNOTSUPP; 3012 3013 /* 3014 * If the caller has CAP_MAC_ADMIN, then get the raw context 3015 * value even if it is not defined by current policy; otherwise, 3016 * use the in-core value under current policy. 3017 * Use the non-auditing forms of the permission checks since 3018 * getxattr may be called by unprivileged processes commonly 3019 * and lack of permission just means that we fall back to the 3020 * in-core context value, not a denial. 3021 */ 3022 error = selinux_capable(current_cred(), &init_user_ns, CAP_MAC_ADMIN, 3023 SECURITY_CAP_NOAUDIT); 3024 if (!error) 3025 error = security_sid_to_context_force(isec->sid, &context, 3026 &size); 3027 else 3028 error = security_sid_to_context(isec->sid, &context, &size); 3029 if (error) 3030 return error; 3031 error = size; 3032 if (alloc) { 3033 *buffer = context; 3034 goto out_nofree; 3035 } 3036 kfree(context); 3037out_nofree: 3038 return error; 3039} 3040 3041static int selinux_inode_setsecurity(struct inode *inode, const char *name, 3042 const void *value, size_t size, int flags) 3043{ 3044 struct inode_security_struct *isec = inode->i_security; 3045 u32 newsid; 3046 int rc; 3047 3048 if (strcmp(name, XATTR_SELINUX_SUFFIX)) 3049 return -EOPNOTSUPP; 3050 3051 if (!value || !size) 3052 return -EACCES; 3053 3054 rc = security_context_to_sid((void *)value, size, &newsid, GFP_KERNEL); 3055 if (rc) 3056 return rc; 3057 3058 isec->sclass = inode_mode_to_security_class(inode->i_mode); 3059 isec->sid = newsid; 3060 isec->initialized = 1; 3061 return 0; 3062} 3063 3064static int selinux_inode_listsecurity(struct inode *inode, char *buffer, size_t buffer_size) 3065{ 3066 const int len = sizeof(XATTR_NAME_SELINUX); 3067 if (buffer && len <= buffer_size) 3068 memcpy(buffer, XATTR_NAME_SELINUX, len); 3069 return len; 3070} 3071 3072static void selinux_inode_getsecid(const struct inode *inode, u32 *secid) 3073{ 3074 struct inode_security_struct *isec = inode->i_security; 3075 *secid = isec->sid; 3076} 3077 3078/* file security operations */ 3079 3080static int selinux_revalidate_file_permission(struct file *file, int mask) 3081{ 3082 const struct cred *cred = current_cred(); 3083 struct inode *inode = file_inode(file); 3084 3085 /* file_mask_to_av won't add FILE__WRITE if MAY_APPEND is set */ 3086 if ((file->f_flags & O_APPEND) && (mask & MAY_WRITE)) 3087 mask |= MAY_APPEND; 3088 3089 return file_has_perm(cred, file, 3090 file_mask_to_av(inode->i_mode, mask)); 3091} 3092 3093static int selinux_file_permission(struct file *file, int mask) 3094{ 3095 struct inode *inode = file_inode(file); 3096 struct file_security_struct *fsec = file->f_security; 3097 struct inode_security_struct *isec = inode->i_security; 3098 u32 sid = current_sid(); 3099 3100 if (!mask) 3101 /* No permission to check. Existence test. */ 3102 return 0; 3103 3104 if (sid == fsec->sid && fsec->isid == isec->sid && 3105 fsec->pseqno == avc_policy_seqno()) 3106 /* No change since file_open check. */ 3107 return 0; 3108 3109 return selinux_revalidate_file_permission(file, mask); 3110} 3111 3112static int selinux_file_alloc_security(struct file *file) 3113{ 3114 return file_alloc_security(file); 3115} 3116 3117static void selinux_file_free_security(struct file *file) 3118{ 3119 file_free_security(file); 3120} 3121 3122static int selinux_file_ioctl(struct file *file, unsigned int cmd, 3123 unsigned long arg) 3124{ 3125 const struct cred *cred = current_cred(); 3126 int error = 0; 3127 3128 switch (cmd) { 3129 case FIONREAD: 3130 /* fall through */ 3131 case FIBMAP: 3132 /* fall through */ 3133 case FIGETBSZ: 3134 /* fall through */ 3135 case FS_IOC_GETFLAGS: 3136 /* fall through */ 3137 case FS_IOC_GETVERSION: 3138 error = file_has_perm(cred, file, FILE__GETATTR); 3139 break; 3140 3141 case FS_IOC_SETFLAGS: 3142 /* fall through */ 3143 case FS_IOC_SETVERSION: 3144 error = file_has_perm(cred, file, FILE__SETATTR); 3145 break; 3146 3147 /* sys_ioctl() checks */ 3148 case FIONBIO: 3149 /* fall through */ 3150 case FIOASYNC: 3151 error = file_has_perm(cred, file, 0); 3152 break; 3153 3154 case KDSKBENT: 3155 case KDSKBSENT: 3156 error = cred_has_capability(cred, CAP_SYS_TTY_CONFIG, 3157 SECURITY_CAP_AUDIT); 3158 break; 3159 3160 /* default case assumes that the command will go 3161 * to the file's ioctl() function. 3162 */ 3163 default: 3164 error = file_has_perm(cred, file, FILE__IOCTL); 3165 } 3166 return error; 3167} 3168 3169static int default_noexec; 3170 3171static int file_map_prot_check(struct file *file, unsigned long prot, int shared) 3172{ 3173 const struct cred *cred = current_cred(); 3174 int rc = 0; 3175 3176 if (default_noexec && 3177 (prot & PROT_EXEC) && (!file || (!shared && (prot & PROT_WRITE)))) { 3178 /* 3179 * We are making executable an anonymous mapping or a 3180 * private file mapping that will also be writable. 3181 * This has an additional check. 3182 */ 3183 rc = cred_has_perm(cred, cred, PROCESS__EXECMEM); 3184 if (rc) 3185 goto error; 3186 } 3187 3188 if (file) { 3189 /* read access is always possible with a mapping */ 3190 u32 av = FILE__READ; 3191 3192 /* write access only matters if the mapping is shared */ 3193 if (shared && (prot & PROT_WRITE)) 3194 av |= FILE__WRITE; 3195 3196 if (prot & PROT_EXEC) 3197 av |= FILE__EXECUTE; 3198 3199 return file_has_perm(cred, file, av); 3200 } 3201 3202error: 3203 return rc; 3204} 3205 3206static int selinux_mmap_addr(unsigned long addr) 3207{ 3208 int rc = 0; 3209 u32 sid = current_sid(); 3210 3211 /* 3212 * notice that we are intentionally putting the SELinux check before 3213 * the secondary cap_file_mmap check. This is such a likely attempt 3214 * at bad behaviour/exploit that we always want to get the AVC, even 3215 * if DAC would have also denied the operation. 3216 */ 3217 if (addr < CONFIG_LSM_MMAP_MIN_ADDR) { 3218 rc = avc_has_perm(sid, sid, SECCLASS_MEMPROTECT, 3219 MEMPROTECT__MMAP_ZERO, NULL); 3220 if (rc) 3221 return rc; 3222 } 3223 3224 /* do DAC check on address space usage */ 3225 return cap_mmap_addr(addr); 3226} 3227 3228static int selinux_mmap_file(struct file *file, unsigned long reqprot, 3229 unsigned long prot, unsigned long flags) 3230{ 3231 if (selinux_checkreqprot) 3232 prot = reqprot; 3233 3234 return file_map_prot_check(file, prot, 3235 (flags & MAP_TYPE) == MAP_SHARED); 3236} 3237 3238static int selinux_file_mprotect(struct vm_area_struct *vma, 3239 unsigned long reqprot, 3240 unsigned long prot) 3241{ 3242 const struct cred *cred = current_cred(); 3243 3244 if (selinux_checkreqprot) 3245 prot = reqprot; 3246 3247 if (default_noexec && 3248 (prot & PROT_EXEC) && !(vma->vm_flags & VM_EXEC)) { 3249 int rc = 0; 3250 if (vma->vm_start >= vma->vm_mm->start_brk && 3251 vma->vm_end <= vma->vm_mm->brk) { 3252 rc = cred_has_perm(cred, cred, PROCESS__EXECHEAP); 3253 } else if (!vma->vm_file && 3254 vma->vm_start <= vma->vm_mm->start_stack && 3255 vma->vm_end >= vma->vm_mm->start_stack) { 3256 rc = current_has_perm(current, PROCESS__EXECSTACK); 3257 } else if (vma->vm_file && vma->anon_vma) { 3258 /* 3259 * We are making executable a file mapping that has 3260 * had some COW done. Since pages might have been 3261 * written, check ability to execute the possibly 3262 * modified content. This typically should only 3263 * occur for text relocations. 3264 */ 3265 rc = file_has_perm(cred, vma->vm_file, FILE__EXECMOD); 3266 } 3267 if (rc) 3268 return rc; 3269 } 3270 3271 return file_map_prot_check(vma->vm_file, prot, vma->vm_flags&VM_SHARED); 3272} 3273 3274static int selinux_file_lock(struct file *file, unsigned int cmd) 3275{ 3276 const struct cred *cred = current_cred(); 3277 3278 return file_has_perm(cred, file, FILE__LOCK); 3279} 3280 3281static int selinux_file_fcntl(struct file *file, unsigned int cmd, 3282 unsigned long arg) 3283{ 3284 const struct cred *cred = current_cred(); 3285 int err = 0; 3286 3287 switch (cmd) { 3288 case F_SETFL: 3289 if ((file->f_flags & O_APPEND) && !(arg & O_APPEND)) { 3290 err = file_has_perm(cred, file, FILE__WRITE); 3291 break; 3292 } 3293 /* fall through */ 3294 case F_SETOWN: 3295 case F_SETSIG: 3296 case F_GETFL: 3297 case F_GETOWN: 3298 case F_GETSIG: 3299 case F_GETOWNER_UIDS: 3300 /* Just check FD__USE permission */ 3301 err = file_has_perm(cred, file, 0); 3302 break; 3303 case F_GETLK: 3304 case F_SETLK: 3305 case F_SETLKW: 3306#if BITS_PER_LONG == 32 3307 case F_GETLK64: 3308 case F_SETLK64: 3309 case F_SETLKW64: 3310#endif 3311 err = file_has_perm(cred, file, FILE__LOCK); 3312 break; 3313 } 3314 3315 return err; 3316} 3317 3318static int selinux_file_set_fowner(struct file *file) 3319{ 3320 struct file_security_struct *fsec; 3321 3322 fsec = file->f_security; 3323 fsec->fown_sid = current_sid(); 3324 3325 return 0; 3326} 3327 3328static int selinux_file_send_sigiotask(struct task_struct *tsk, 3329 struct fown_struct *fown, int signum) 3330{ 3331 struct file *file; 3332 u32 sid = task_sid(tsk); 3333 u32 perm; 3334 struct file_security_struct *fsec; 3335 3336 /* struct fown_struct is never outside the context of a struct file */ 3337 file = container_of(fown, struct file, f_owner); 3338 3339 fsec = file->f_security; 3340 3341 if (!signum) 3342 perm = signal_to_av(SIGIO); /* as per send_sigio_to_task */ 3343 else 3344 perm = signal_to_av(signum); 3345 3346 return avc_has_perm(fsec->fown_sid, sid, 3347 SECCLASS_PROCESS, perm, NULL); 3348} 3349 3350static int selinux_file_receive(struct file *file) 3351{ 3352 const struct cred *cred = current_cred(); 3353 3354 return file_has_perm(cred, file, file_to_av(file)); 3355} 3356 3357static int selinux_file_open(struct file *file, const struct cred *cred) 3358{ 3359 struct file_security_struct *fsec; 3360 struct inode_security_struct *isec; 3361 3362 fsec = file->f_security; 3363 isec = file_inode(file)->i_security; 3364 /* 3365 * Save inode label and policy sequence number 3366 * at open-time so that selinux_file_permission 3367 * can determine whether revalidation is necessary. 3368 * Task label is already saved in the file security 3369 * struct as its SID. 3370 */ 3371 fsec->isid = isec->sid; 3372 fsec->pseqno = avc_policy_seqno(); 3373 /* 3374 * Since the inode label or policy seqno may have changed 3375 * between the selinux_inode_permission check and the saving 3376 * of state above, recheck that access is still permitted. 3377 * Otherwise, access might never be revalidated against the 3378 * new inode label or new policy. 3379 * This check is not redundant - do not remove. 3380 */ 3381 return file_path_has_perm(cred, file, open_file_to_av(file)); 3382} 3383 3384/* task security operations */ 3385 3386static int selinux_task_create(unsigned long clone_flags) 3387{ 3388 return current_has_perm(current, PROCESS__FORK); 3389} 3390 3391/* 3392 * allocate the SELinux part of blank credentials 3393 */ 3394static int selinux_cred_alloc_blank(struct cred *cred, gfp_t gfp) 3395{ 3396 struct task_security_struct *tsec; 3397 3398 tsec = kzalloc(sizeof(struct task_security_struct), gfp); 3399 if (!tsec) 3400 return -ENOMEM; 3401 3402 cred->security = tsec; 3403 return 0; 3404} 3405 3406/* 3407 * detach and free the LSM part of a set of credentials 3408 */ 3409static void selinux_cred_free(struct cred *cred) 3410{ 3411 struct task_security_struct *tsec = cred->security; 3412 3413 /* 3414 * cred->security == NULL if security_cred_alloc_blank() or 3415 * security_prepare_creds() returned an error. 3416 */ 3417 BUG_ON(cred->security && (unsigned long) cred->security < PAGE_SIZE); 3418 cred->security = (void *) 0x7UL; 3419 kfree(tsec); 3420} 3421 3422/* 3423 * prepare a new set of credentials for modification 3424 */ 3425static int selinux_cred_prepare(struct cred *new, const struct cred *old, 3426 gfp_t gfp) 3427{ 3428 const struct task_security_struct *old_tsec; 3429 struct task_security_struct *tsec; 3430 3431 old_tsec = old->security; 3432 3433 tsec = kmemdup(old_tsec, sizeof(struct task_security_struct), gfp); 3434 if (!tsec) 3435 return -ENOMEM; 3436 3437 new->security = tsec; 3438 return 0; 3439} 3440 3441/* 3442 * transfer the SELinux data to a blank set of creds 3443 */ 3444static void selinux_cred_transfer(struct cred *new, const struct cred *old) 3445{ 3446 const struct task_security_struct *old_tsec = old->security; 3447 struct task_security_struct *tsec = new->security; 3448 3449 *tsec = *old_tsec; 3450} 3451 3452/* 3453 * set the security data for a kernel service 3454 * - all the creation contexts are set to unlabelled 3455 */ 3456static int selinux_kernel_act_as(struct cred *new, u32 secid) 3457{ 3458 struct task_security_struct *tsec = new->security; 3459 u32 sid = current_sid(); 3460 int ret; 3461 3462 ret = avc_has_perm(sid, secid, 3463 SECCLASS_KERNEL_SERVICE, 3464 KERNEL_SERVICE__USE_AS_OVERRIDE, 3465 NULL); 3466 if (ret == 0) { 3467 tsec->sid = secid; 3468 tsec->create_sid = 0; 3469 tsec->keycreate_sid = 0; 3470 tsec->sockcreate_sid = 0; 3471 } 3472 return ret; 3473} 3474 3475/* 3476 * set the file creation context in a security record to the same as the 3477 * objective context of the specified inode 3478 */ 3479static int selinux_kernel_create_files_as(struct cred *new, struct inode *inode) 3480{ 3481 struct inode_security_struct *isec = inode->i_security; 3482 struct task_security_struct *tsec = new->security; 3483 u32 sid = current_sid(); 3484 int ret; 3485 3486 ret = avc_has_perm(sid, isec->sid, 3487 SECCLASS_KERNEL_SERVICE, 3488 KERNEL_SERVICE__CREATE_FILES_AS, 3489 NULL); 3490 3491 if (ret == 0) 3492 tsec->create_sid = isec->sid; 3493 return ret; 3494} 3495 3496static int selinux_kernel_module_request(char *kmod_name) 3497{ 3498 u32 sid; 3499 struct common_audit_data ad; 3500 3501 sid = task_sid(current); 3502 3503 ad.type = LSM_AUDIT_DATA_KMOD; 3504 ad.u.kmod_name = kmod_name; 3505 3506 return avc_has_perm(sid, SECINITSID_KERNEL, SECCLASS_SYSTEM, 3507 SYSTEM__MODULE_REQUEST, &ad); 3508} 3509 3510static int selinux_task_setpgid(struct task_struct *p, pid_t pgid) 3511{ 3512 return current_has_perm(p, PROCESS__SETPGID); 3513} 3514 3515static int selinux_task_getpgid(struct task_struct *p) 3516{ 3517 return current_has_perm(p, PROCESS__GETPGID); 3518} 3519 3520static int selinux_task_getsid(struct task_struct *p) 3521{ 3522 return current_has_perm(p, PROCESS__GETSESSION); 3523} 3524 3525static void selinux_task_getsecid(struct task_struct *p, u32 *secid) 3526{ 3527 *secid = task_sid(p); 3528} 3529 3530static int selinux_task_setnice(struct task_struct *p, int nice) 3531{ 3532 int rc; 3533 3534 rc = cap_task_setnice(p, nice); 3535 if (rc) 3536 return rc; 3537 3538 return current_has_perm(p, PROCESS__SETSCHED); 3539} 3540 3541static int selinux_task_setioprio(struct task_struct *p, int ioprio) 3542{ 3543 int rc; 3544 3545 rc = cap_task_setioprio(p, ioprio); 3546 if (rc) 3547 return rc; 3548 3549 return current_has_perm(p, PROCESS__SETSCHED); 3550} 3551 3552static int selinux_task_getioprio(struct task_struct *p) 3553{ 3554 return current_has_perm(p, PROCESS__GETSCHED); 3555} 3556 3557static int selinux_task_setrlimit(struct task_struct *p, unsigned int resource, 3558 struct rlimit *new_rlim) 3559{ 3560 struct rlimit *old_rlim = p->signal->rlim + resource; 3561 3562 /* Control the ability to change the hard limit (whether 3563 lowering or raising it), so that the hard limit can 3564 later be used as a safe reset point for the soft limit 3565 upon context transitions. See selinux_bprm_committing_creds. */ 3566 if (old_rlim->rlim_max != new_rlim->rlim_max) 3567 return current_has_perm(p, PROCESS__SETRLIMIT); 3568 3569 return 0; 3570} 3571 3572static int selinux_task_setscheduler(struct task_struct *p) 3573{ 3574 int rc; 3575 3576 rc = cap_task_setscheduler(p); 3577 if (rc) 3578 return rc; 3579 3580 return current_has_perm(p, PROCESS__SETSCHED); 3581} 3582 3583static int selinux_task_getscheduler(struct task_struct *p) 3584{ 3585 return current_has_perm(p, PROCESS__GETSCHED); 3586} 3587 3588static int selinux_task_movememory(struct task_struct *p) 3589{ 3590 return current_has_perm(p, PROCESS__SETSCHED); 3591} 3592 3593static int selinux_task_kill(struct task_struct *p, struct siginfo *info, 3594 int sig, u32 secid) 3595{ 3596 u32 perm; 3597 int rc; 3598 3599 if (!sig) 3600 perm = PROCESS__SIGNULL; /* null signal; existence test */ 3601 else 3602 perm = signal_to_av(sig); 3603 if (secid) 3604 rc = avc_has_perm(secid, task_sid(p), 3605 SECCLASS_PROCESS, perm, NULL); 3606 else 3607 rc = current_has_perm(p, perm); 3608 return rc; 3609} 3610 3611static int selinux_task_wait(struct task_struct *p) 3612{ 3613 return task_has_perm(p, current, PROCESS__SIGCHLD); 3614} 3615 3616static void selinux_task_to_inode(struct task_struct *p, 3617 struct inode *inode) 3618{ 3619 struct inode_security_struct *isec = inode->i_security; 3620 u32 sid = task_sid(p); 3621 3622 isec->sid = sid; 3623 isec->initialized = 1; 3624} 3625 3626/* Returns error only if unable to parse addresses */ 3627static int selinux_parse_skb_ipv4(struct sk_buff *skb, 3628 struct common_audit_data *ad, u8 *proto) 3629{ 3630 int offset, ihlen, ret = -EINVAL; 3631 struct iphdr _iph, *ih; 3632 3633 offset = skb_network_offset(skb); 3634 ih = skb_header_pointer(skb, offset, sizeof(_iph), &_iph); 3635 if (ih == NULL) 3636 goto out; 3637 3638 ihlen = ih->ihl * 4; 3639 if (ihlen < sizeof(_iph)) 3640 goto out; 3641 3642 ad->u.net->v4info.saddr = ih->saddr; 3643 ad->u.net->v4info.daddr = ih->daddr; 3644 ret = 0; 3645 3646 if (proto) 3647 *proto = ih->protocol; 3648 3649 switch (ih->protocol) { 3650 case IPPROTO_TCP: { 3651 struct tcphdr _tcph, *th; 3652 3653 if (ntohs(ih->frag_off) & IP_OFFSET) 3654 break; 3655 3656 offset += ihlen; 3657 th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph); 3658 if (th == NULL) 3659 break; 3660 3661 ad->u.net->sport = th->source; 3662 ad->u.net->dport = th->dest; 3663 break; 3664 } 3665 3666 case IPPROTO_UDP: { 3667 struct udphdr _udph, *uh; 3668 3669 if (ntohs(ih->frag_off) & IP_OFFSET) 3670 break; 3671 3672 offset += ihlen; 3673 uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph); 3674 if (uh == NULL) 3675 break; 3676 3677 ad->u.net->sport = uh->source; 3678 ad->u.net->dport = uh->dest; 3679 break; 3680 } 3681 3682 case IPPROTO_DCCP: { 3683 struct dccp_hdr _dccph, *dh; 3684 3685 if (ntohs(ih->frag_off) & IP_OFFSET) 3686 break; 3687 3688 offset += ihlen; 3689 dh = skb_header_pointer(skb, offset, sizeof(_dccph), &_dccph); 3690 if (dh == NULL) 3691 break; 3692 3693 ad->u.net->sport = dh->dccph_sport; 3694 ad->u.net->dport = dh->dccph_dport; 3695 break; 3696 } 3697 3698 default: 3699 break; 3700 } 3701out: 3702 return ret; 3703} 3704 3705#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE) 3706 3707/* Returns error only if unable to parse addresses */ 3708static int selinux_parse_skb_ipv6(struct sk_buff *skb, 3709 struct common_audit_data *ad, u8 *proto) 3710{ 3711 u8 nexthdr; 3712 int ret = -EINVAL, offset; 3713 struct ipv6hdr _ipv6h, *ip6; 3714 __be16 frag_off; 3715 3716 offset = skb_network_offset(skb); 3717 ip6 = skb_header_pointer(skb, offset, sizeof(_ipv6h), &_ipv6h); 3718 if (ip6 == NULL) 3719 goto out; 3720 3721 ad->u.net->v6info.saddr = ip6->saddr; 3722 ad->u.net->v6info.daddr = ip6->daddr; 3723 ret = 0; 3724 3725 nexthdr = ip6->nexthdr; 3726 offset += sizeof(_ipv6h); 3727 offset = ipv6_skip_exthdr(skb, offset, &nexthdr, &frag_off); 3728 if (offset < 0) 3729 goto out; 3730 3731 if (proto) 3732 *proto = nexthdr; 3733 3734 switch (nexthdr) { 3735 case IPPROTO_TCP: { 3736 struct tcphdr _tcph, *th; 3737 3738 th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph); 3739 if (th == NULL) 3740 break; 3741 3742 ad->u.net->sport = th->source; 3743 ad->u.net->dport = th->dest; 3744 break; 3745 } 3746 3747 case IPPROTO_UDP: { 3748 struct udphdr _udph, *uh; 3749 3750 uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph); 3751 if (uh == NULL) 3752 break; 3753 3754 ad->u.net->sport = uh->source; 3755 ad->u.net->dport = uh->dest; 3756 break; 3757 } 3758 3759 case IPPROTO_DCCP: { 3760 struct dccp_hdr _dccph, *dh; 3761 3762 dh = skb_header_pointer(skb, offset, sizeof(_dccph), &_dccph); 3763 if (dh == NULL) 3764 break; 3765 3766 ad->u.net->sport = dh->dccph_sport; 3767 ad->u.net->dport = dh->dccph_dport; 3768 break; 3769 } 3770 3771 /* includes fragments */ 3772 default: 3773 break; 3774 } 3775out: 3776 return ret; 3777} 3778 3779#endif /* IPV6 */ 3780 3781static int selinux_parse_skb(struct sk_buff *skb, struct common_audit_data *ad, 3782 char **_addrp, int src, u8 *proto) 3783{ 3784 char *addrp; 3785 int ret; 3786 3787 switch (ad->u.net->family) { 3788 case PF_INET: 3789 ret = selinux_parse_skb_ipv4(skb, ad, proto); 3790 if (ret) 3791 goto parse_error; 3792 addrp = (char *)(src ? &ad->u.net->v4info.saddr : 3793 &ad->u.net->v4info.daddr); 3794 goto okay; 3795 3796#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE) 3797 case PF_INET6: 3798 ret = selinux_parse_skb_ipv6(skb, ad, proto); 3799 if (ret) 3800 goto parse_error; 3801 addrp = (char *)(src ? &ad->u.net->v6info.saddr : 3802 &ad->u.net->v6info.daddr); 3803 goto okay; 3804#endif /* IPV6 */ 3805 default: 3806 addrp = NULL; 3807 goto okay; 3808 } 3809 3810parse_error: 3811 printk(KERN_WARNING 3812 "SELinux: failure in selinux_parse_skb()," 3813 " unable to parse packet\n"); 3814 return ret; 3815 3816okay: 3817 if (_addrp) 3818 *_addrp = addrp; 3819 return 0; 3820} 3821 3822/** 3823 * selinux_skb_peerlbl_sid - Determine the peer label of a packet 3824 * @skb: the packet 3825 * @family: protocol family 3826 * @sid: the packet's peer label SID 3827 * 3828 * Description: 3829 * Check the various different forms of network peer labeling and determine 3830 * the peer label/SID for the packet; most of the magic actually occurs in 3831 * the security server function security_net_peersid_cmp(). The function 3832 * returns zero if the value in @sid is valid (although it may be SECSID_NULL) 3833 * or -EACCES if @sid is invalid due to inconsistencies with the different 3834 * peer labels. 3835 * 3836 */ 3837static int selinux_skb_peerlbl_sid(struct sk_buff *skb, u16 family, u32 *sid) 3838{ 3839 int err; 3840 u32 xfrm_sid; 3841 u32 nlbl_sid; 3842 u32 nlbl_type; 3843 3844 err = selinux_xfrm_skb_sid(skb, &xfrm_sid); 3845 if (unlikely(err)) 3846 return -EACCES; 3847 err = selinux_netlbl_skbuff_getsid(skb, family, &nlbl_type, &nlbl_sid); 3848 if (unlikely(err)) 3849 return -EACCES; 3850 3851 err = security_net_peersid_resolve(nlbl_sid, nlbl_type, xfrm_sid, sid); 3852 if (unlikely(err)) { 3853 printk(KERN_WARNING 3854 "SELinux: failure in selinux_skb_peerlbl_sid()," 3855 " unable to determine packet's peer label\n"); 3856 return -EACCES; 3857 } 3858 3859 return 0; 3860} 3861 3862/** 3863 * selinux_conn_sid - Determine the child socket label for a connection 3864 * @sk_sid: the parent socket's SID 3865 * @skb_sid: the packet's SID 3866 * @conn_sid: the resulting connection SID 3867 * 3868 * If @skb_sid is valid then the user:role:type information from @sk_sid is 3869 * combined with the MLS information from @skb_sid in order to create 3870 * @conn_sid. If @skb_sid is not valid then then @conn_sid is simply a copy 3871 * of @sk_sid. Returns zero on success, negative values on failure. 3872 * 3873 */ 3874static int selinux_conn_sid(u32 sk_sid, u32 skb_sid, u32 *conn_sid) 3875{ 3876 int err = 0; 3877 3878 if (skb_sid != SECSID_NULL) 3879 err = security_sid_mls_copy(sk_sid, skb_sid, conn_sid); 3880 else 3881 *conn_sid = sk_sid; 3882 3883 return err; 3884} 3885 3886/* socket security operations */ 3887 3888static int socket_sockcreate_sid(const struct task_security_struct *tsec, 3889 u16 secclass, u32 *socksid) 3890{ 3891 if (tsec->sockcreate_sid > SECSID_NULL) { 3892 *socksid = tsec->sockcreate_sid; 3893 return 0; 3894 } 3895 3896 return security_transition_sid(tsec->sid, tsec->sid, secclass, NULL, 3897 socksid); 3898} 3899 3900static int sock_has_perm(struct task_struct *task, struct sock *sk, u32 perms) 3901{ 3902 struct sk_security_struct *sksec = sk->sk_security; 3903 struct common_audit_data ad; 3904 struct lsm_network_audit net = {0,}; 3905 u32 tsid = task_sid(task); 3906 3907 if (sksec->sid == SECINITSID_KERNEL) 3908 return 0; 3909 3910 ad.type = LSM_AUDIT_DATA_NET; 3911 ad.u.net = &net; 3912 ad.u.net->sk = sk; 3913 3914 return avc_has_perm(tsid, sksec->sid, sksec->sclass, perms, &ad); 3915} 3916 3917static int selinux_socket_create(int family, int type, 3918 int protocol, int kern) 3919{ 3920 const struct task_security_struct *tsec = current_security(); 3921 u32 newsid; 3922 u16 secclass; 3923 int rc; 3924 3925 if (kern) 3926 return 0; 3927 3928 secclass = socket_type_to_security_class(family, type, protocol); 3929 rc = socket_sockcreate_sid(tsec, secclass, &newsid); 3930 if (rc) 3931 return rc; 3932 3933 return avc_has_perm(tsec->sid, newsid, secclass, SOCKET__CREATE, NULL); 3934} 3935 3936static int selinux_socket_post_create(struct socket *sock, int family, 3937 int type, int protocol, int kern) 3938{ 3939 const struct task_security_struct *tsec = current_security(); 3940 struct inode_security_struct *isec = SOCK_INODE(sock)->i_security; 3941 struct sk_security_struct *sksec; 3942 int err = 0; 3943 3944 isec->sclass = socket_type_to_security_class(family, type, protocol); 3945 3946 if (kern) 3947 isec->sid = SECINITSID_KERNEL; 3948 else { 3949 err = socket_sockcreate_sid(tsec, isec->sclass, &(isec->sid)); 3950 if (err) 3951 return err; 3952 } 3953 3954 isec->initialized = 1; 3955 3956 if (sock->sk) { 3957 sksec = sock->sk->sk_security; 3958 sksec->sid = isec->sid; 3959 sksec->sclass = isec->sclass; 3960 err = selinux_netlbl_socket_post_create(sock->sk, family); 3961 } 3962 3963 return err; 3964} 3965 3966/* Range of port numbers used to automatically bind. 3967 Need to determine whether we should perform a name_bind 3968 permission check between the socket and the port number. */ 3969 3970static int selinux_socket_bind(struct socket *sock, struct sockaddr *address, int addrlen) 3971{ 3972 struct sock *sk = sock->sk; 3973 u16 family; 3974 int err; 3975 3976 err = sock_has_perm(current, sk, SOCKET__BIND); 3977 if (err) 3978 goto out; 3979 3980 /* 3981 * If PF_INET or PF_INET6, check name_bind permission for the port. 3982 * Multiple address binding for SCTP is not supported yet: we just 3983 * check the first address now. 3984 */ 3985 family = sk->sk_family; 3986 if (family == PF_INET || family == PF_INET6) { 3987 char *addrp; 3988 struct sk_security_struct *sksec = sk->sk_security; 3989 struct common_audit_data ad; 3990 struct lsm_network_audit net = {0,}; 3991 struct sockaddr_in *addr4 = NULL; 3992 struct sockaddr_in6 *addr6 = NULL; 3993 unsigned short snum; 3994 u32 sid, node_perm; 3995 3996 if (family == PF_INET) { 3997 addr4 = (struct sockaddr_in *)address; 3998 snum = ntohs(addr4->sin_port); 3999 addrp = (char *)&addr4->sin_addr.s_addr; 4000 } else { 4001 addr6 = (struct sockaddr_in6 *)address; 4002 snum = ntohs(addr6->sin6_port); 4003 addrp = (char *)&addr6->sin6_addr.s6_addr; 4004 } 4005 4006 if (snum) { 4007 int low, high; 4008 4009 inet_get_local_port_range(sock_net(sk), &low, &high); 4010 4011 if (snum < max(PROT_SOCK, low) || snum > high) { 4012 err = sel_netport_sid(sk->sk_protocol, 4013 snum, &sid); 4014 if (err) 4015 goto out; 4016 ad.type = LSM_AUDIT_DATA_NET; 4017 ad.u.net = &net; 4018 ad.u.net->sport = htons(snum); 4019 ad.u.net->family = family; 4020 err = avc_has_perm(sksec->sid, sid, 4021 sksec->sclass, 4022 SOCKET__NAME_BIND, &ad); 4023 if (err) 4024 goto out; 4025 } 4026 } 4027 4028 switch (sksec->sclass) { 4029 case SECCLASS_TCP_SOCKET: 4030 node_perm = TCP_SOCKET__NODE_BIND; 4031 break; 4032 4033 case SECCLASS_UDP_SOCKET: 4034 node_perm = UDP_SOCKET__NODE_BIND; 4035 break; 4036 4037 case SECCLASS_DCCP_SOCKET: 4038 node_perm = DCCP_SOCKET__NODE_BIND; 4039 break; 4040 4041 default: 4042 node_perm = RAWIP_SOCKET__NODE_BIND; 4043 break; 4044 } 4045 4046 err = sel_netnode_sid(addrp, family, &sid); 4047 if (err) 4048 goto out; 4049 4050 ad.type = LSM_AUDIT_DATA_NET; 4051 ad.u.net = &net; 4052 ad.u.net->sport = htons(snum); 4053 ad.u.net->family = family; 4054 4055 if (family == PF_INET) 4056 ad.u.net->v4info.saddr = addr4->sin_addr.s_addr; 4057 else 4058 ad.u.net->v6info.saddr = addr6->sin6_addr; 4059 4060 err = avc_has_perm(sksec->sid, sid, 4061 sksec->sclass, node_perm, &ad); 4062 if (err) 4063 goto out; 4064 } 4065out: 4066 return err; 4067} 4068 4069static int selinux_socket_connect(struct socket *sock, struct sockaddr *address, int addrlen) 4070{ 4071 struct sock *sk = sock->sk; 4072 struct sk_security_struct *sksec = sk->sk_security; 4073 int err; 4074 4075 err = sock_has_perm(current, sk, SOCKET__CONNECT); 4076 if (err) 4077 return err; 4078 4079 /* 4080 * If a TCP or DCCP socket, check name_connect permission for the port. 4081 */ 4082 if (sksec->sclass == SECCLASS_TCP_SOCKET || 4083 sksec->sclass == SECCLASS_DCCP_SOCKET) { 4084 struct common_audit_data ad; 4085 struct lsm_network_audit net = {0,}; 4086 struct sockaddr_in *addr4 = NULL; 4087 struct sockaddr_in6 *addr6 = NULL; 4088 unsigned short snum; 4089 u32 sid, perm; 4090 4091 if (sk->sk_family == PF_INET) { 4092 addr4 = (struct sockaddr_in *)address; 4093 if (addrlen < sizeof(struct sockaddr_in)) 4094 return -EINVAL; 4095 snum = ntohs(addr4->sin_port); 4096 } else { 4097 addr6 = (struct sockaddr_in6 *)address; 4098 if (addrlen < SIN6_LEN_RFC2133) 4099 return -EINVAL; 4100 snum = ntohs(addr6->sin6_port); 4101 } 4102 4103 err = sel_netport_sid(sk->sk_protocol, snum, &sid); 4104 if (err) 4105 goto out; 4106 4107 perm = (sksec->sclass == SECCLASS_TCP_SOCKET) ? 4108 TCP_SOCKET__NAME_CONNECT : DCCP_SOCKET__NAME_CONNECT; 4109 4110 ad.type = LSM_AUDIT_DATA_NET; 4111 ad.u.net = &net; 4112 ad.u.net->dport = htons(snum); 4113 ad.u.net->family = sk->sk_family; 4114 err = avc_has_perm(sksec->sid, sid, sksec->sclass, perm, &ad); 4115 if (err) 4116 goto out; 4117 } 4118 4119 err = selinux_netlbl_socket_connect(sk, address); 4120 4121out: 4122 return err; 4123} 4124 4125static int selinux_socket_listen(struct socket *sock, int backlog) 4126{ 4127 return sock_has_perm(current, sock->sk, SOCKET__LISTEN); 4128} 4129 4130static int selinux_socket_accept(struct socket *sock, struct socket *newsock) 4131{ 4132 int err; 4133 struct inode_security_struct *isec; 4134 struct inode_security_struct *newisec; 4135 4136 err = sock_has_perm(current, sock->sk, SOCKET__ACCEPT); 4137 if (err) 4138 return err; 4139 4140 newisec = SOCK_INODE(newsock)->i_security; 4141 4142 isec = SOCK_INODE(sock)->i_security; 4143 newisec->sclass = isec->sclass; 4144 newisec->sid = isec->sid; 4145 newisec->initialized = 1; 4146 4147 return 0; 4148} 4149 4150static int selinux_socket_sendmsg(struct socket *sock, struct msghdr *msg, 4151 int size) 4152{ 4153 return sock_has_perm(current, sock->sk, SOCKET__WRITE); 4154} 4155 4156static int selinux_socket_recvmsg(struct socket *sock, struct msghdr *msg, 4157 int size, int flags) 4158{ 4159 return sock_has_perm(current, sock->sk, SOCKET__READ); 4160} 4161 4162static int selinux_socket_getsockname(struct socket *sock) 4163{ 4164 return sock_has_perm(current, sock->sk, SOCKET__GETATTR); 4165} 4166 4167static int selinux_socket_getpeername(struct socket *sock) 4168{ 4169 return sock_has_perm(current, sock->sk, SOCKET__GETATTR); 4170} 4171 4172static int selinux_socket_setsockopt(struct socket *sock, int level, int optname) 4173{ 4174 int err; 4175 4176 err = sock_has_perm(current, sock->sk, SOCKET__SETOPT); 4177 if (err) 4178 return err; 4179 4180 return selinux_netlbl_socket_setsockopt(sock, level, optname); 4181} 4182 4183static int selinux_socket_getsockopt(struct socket *sock, int level, 4184 int optname) 4185{ 4186 return sock_has_perm(current, sock->sk, SOCKET__GETOPT); 4187} 4188 4189static int selinux_socket_shutdown(struct socket *sock, int how) 4190{ 4191 return sock_has_perm(current, sock->sk, SOCKET__SHUTDOWN); 4192} 4193 4194static int selinux_socket_unix_stream_connect(struct sock *sock, 4195 struct sock *other, 4196 struct sock *newsk) 4197{ 4198 struct sk_security_struct *sksec_sock = sock->sk_security; 4199 struct sk_security_struct *sksec_other = other->sk_security; 4200 struct sk_security_struct *sksec_new = newsk->sk_security; 4201 struct common_audit_data ad; 4202 struct lsm_network_audit net = {0,}; 4203 int err; 4204 4205 ad.type = LSM_AUDIT_DATA_NET; 4206 ad.u.net = &net; 4207 ad.u.net->sk = other; 4208 4209 err = avc_has_perm(sksec_sock->sid, sksec_other->sid, 4210 sksec_other->sclass, 4211 UNIX_STREAM_SOCKET__CONNECTTO, &ad); 4212 if (err) 4213 return err; 4214 4215 /* server child socket */ 4216 sksec_new->peer_sid = sksec_sock->sid; 4217 err = security_sid_mls_copy(sksec_other->sid, sksec_sock->sid, 4218 &sksec_new->sid); 4219 if (err) 4220 return err; 4221 4222 /* connecting socket */ 4223 sksec_sock->peer_sid = sksec_new->sid; 4224 4225 return 0; 4226} 4227 4228static int selinux_socket_unix_may_send(struct socket *sock, 4229 struct socket *other) 4230{ 4231 struct sk_security_struct *ssec = sock->sk->sk_security; 4232 struct sk_security_struct *osec = other->sk->sk_security; 4233 struct common_audit_data ad; 4234 struct lsm_network_audit net = {0,}; 4235 4236 ad.type = LSM_AUDIT_DATA_NET; 4237 ad.u.net = &net; 4238 ad.u.net->sk = other->sk; 4239 4240 return avc_has_perm(ssec->sid, osec->sid, osec->sclass, SOCKET__SENDTO, 4241 &ad); 4242} 4243 4244static int selinux_inet_sys_rcv_skb(int ifindex, char *addrp, u16 family, 4245 u32 peer_sid, 4246 struct common_audit_data *ad) 4247{ 4248 int err; 4249 u32 if_sid; 4250 u32 node_sid; 4251 4252 err = sel_netif_sid(ifindex, &if_sid); 4253 if (err) 4254 return err; 4255 err = avc_has_perm(peer_sid, if_sid, 4256 SECCLASS_NETIF, NETIF__INGRESS, ad); 4257 if (err) 4258 return err; 4259 4260 err = sel_netnode_sid(addrp, family, &node_sid); 4261 if (err) 4262 return err; 4263 return avc_has_perm(peer_sid, node_sid, 4264 SECCLASS_NODE, NODE__RECVFROM, ad); 4265} 4266 4267static int selinux_sock_rcv_skb_compat(struct sock *sk, struct sk_buff *skb, 4268 u16 family) 4269{ 4270 int err = 0; 4271 struct sk_security_struct *sksec = sk->sk_security; 4272 u32 sk_sid = sksec->sid; 4273 struct common_audit_data ad; 4274 struct lsm_network_audit net = {0,}; 4275 char *addrp; 4276 4277 ad.type = LSM_AUDIT_DATA_NET; 4278 ad.u.net = &net; 4279 ad.u.net->netif = skb->skb_iif; 4280 ad.u.net->family = family; 4281 err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL); 4282 if (err) 4283 return err; 4284 4285 if (selinux_secmark_enabled()) { 4286 err = avc_has_perm(sk_sid, skb->secmark, SECCLASS_PACKET, 4287 PACKET__RECV, &ad); 4288 if (err) 4289 return err; 4290 } 4291 4292 err = selinux_netlbl_sock_rcv_skb(sksec, skb, family, &ad); 4293 if (err) 4294 return err; 4295 err = selinux_xfrm_sock_rcv_skb(sksec->sid, skb, &ad); 4296 4297 return err; 4298} 4299 4300static int selinux_socket_sock_rcv_skb(struct sock *sk, struct sk_buff *skb) 4301{ 4302 int err; 4303 struct sk_security_struct *sksec = sk->sk_security; 4304 u16 family = sk->sk_family; 4305 u32 sk_sid = sksec->sid; 4306 struct common_audit_data ad; 4307 struct lsm_network_audit net = {0,}; 4308 char *addrp; 4309 u8 secmark_active; 4310 u8 peerlbl_active; 4311 4312 if (family != PF_INET && family != PF_INET6) 4313 return 0; 4314 4315 /* Handle mapped IPv4 packets arriving via IPv6 sockets */ 4316 if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP)) 4317 family = PF_INET; 4318 4319 /* If any sort of compatibility mode is enabled then handoff processing 4320 * to the selinux_sock_rcv_skb_compat() function to deal with the 4321 * special handling. We do this in an attempt to keep this function 4322 * as fast and as clean as possible. */ 4323 if (!selinux_policycap_netpeer) 4324 return selinux_sock_rcv_skb_compat(sk, skb, family); 4325 4326 secmark_active = selinux_secmark_enabled(); 4327 peerlbl_active = selinux_peerlbl_enabled(); 4328 if (!secmark_active && !peerlbl_active) 4329 return 0; 4330 4331 ad.type = LSM_AUDIT_DATA_NET; 4332 ad.u.net = &net; 4333 ad.u.net->netif = skb->skb_iif; 4334 ad.u.net->family = family; 4335 err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL); 4336 if (err) 4337 return err; 4338 4339 if (peerlbl_active) { 4340 u32 peer_sid; 4341 4342 err = selinux_skb_peerlbl_sid(skb, family, &peer_sid); 4343 if (err) 4344 return err; 4345 err = selinux_inet_sys_rcv_skb(skb->skb_iif, addrp, family, 4346 peer_sid, &ad); 4347 if (err) { 4348 selinux_netlbl_err(skb, err, 0); 4349 return err; 4350 } 4351 err = avc_has_perm(sk_sid, peer_sid, SECCLASS_PEER, 4352 PEER__RECV, &ad); 4353 if (err) { 4354 selinux_netlbl_err(skb, err, 0); 4355 return err; 4356 } 4357 } 4358 4359 if (secmark_active) { 4360 err = avc_has_perm(sk_sid, skb->secmark, SECCLASS_PACKET, 4361 PACKET__RECV, &ad); 4362 if (err) 4363 return err; 4364 } 4365 4366 return err; 4367} 4368 4369static int selinux_socket_getpeersec_stream(struct socket *sock, char __user *optval, 4370 int __user *optlen, unsigned len) 4371{ 4372 int err = 0; 4373 char *scontext; 4374 u32 scontext_len; 4375 struct sk_security_struct *sksec = sock->sk->sk_security; 4376 u32 peer_sid = SECSID_NULL; 4377 4378 if (sksec->sclass == SECCLASS_UNIX_STREAM_SOCKET || 4379 sksec->sclass == SECCLASS_TCP_SOCKET) 4380 peer_sid = sksec->peer_sid; 4381 if (peer_sid == SECSID_NULL) 4382 return -ENOPROTOOPT; 4383 4384 err = security_sid_to_context(peer_sid, &scontext, &scontext_len); 4385 if (err) 4386 return err; 4387 4388 if (scontext_len > len) { 4389 err = -ERANGE; 4390 goto out_len; 4391 } 4392 4393 if (copy_to_user(optval, scontext, scontext_len)) 4394 err = -EFAULT; 4395 4396out_len: 4397 if (put_user(scontext_len, optlen)) 4398 err = -EFAULT; 4399 kfree(scontext); 4400 return err; 4401} 4402 4403static int selinux_socket_getpeersec_dgram(struct socket *sock, struct sk_buff *skb, u32 *secid) 4404{ 4405 u32 peer_secid = SECSID_NULL; 4406 u16 family; 4407 4408 if (skb && skb->protocol == htons(ETH_P_IP)) 4409 family = PF_INET; 4410 else if (skb && skb->protocol == htons(ETH_P_IPV6)) 4411 family = PF_INET6; 4412 else if (sock) 4413 family = sock->sk->sk_family; 4414 else 4415 goto out; 4416 4417 if (sock && family == PF_UNIX) 4418 selinux_inode_getsecid(SOCK_INODE(sock), &peer_secid); 4419 else if (skb) 4420 selinux_skb_peerlbl_sid(skb, family, &peer_secid); 4421 4422out: 4423 *secid = peer_secid; 4424 if (peer_secid == SECSID_NULL) 4425 return -EINVAL; 4426 return 0; 4427} 4428 4429static int selinux_sk_alloc_security(struct sock *sk, int family, gfp_t priority) 4430{ 4431 struct sk_security_struct *sksec; 4432 4433 sksec = kzalloc(sizeof(*sksec), priority); 4434 if (!sksec) 4435 return -ENOMEM; 4436 4437 sksec->peer_sid = SECINITSID_UNLABELED; 4438 sksec->sid = SECINITSID_UNLABELED; 4439 selinux_netlbl_sk_security_reset(sksec); 4440 sk->sk_security = sksec; 4441 4442 return 0; 4443} 4444 4445static void selinux_sk_free_security(struct sock *sk) 4446{ 4447 struct sk_security_struct *sksec = sk->sk_security; 4448 4449 sk->sk_security = NULL; 4450 selinux_netlbl_sk_security_free(sksec); 4451 kfree(sksec); 4452} 4453 4454static void selinux_sk_clone_security(const struct sock *sk, struct sock *newsk) 4455{ 4456 struct sk_security_struct *sksec = sk->sk_security; 4457 struct sk_security_struct *newsksec = newsk->sk_security; 4458 4459 newsksec->sid = sksec->sid; 4460 newsksec->peer_sid = sksec->peer_sid; 4461 newsksec->sclass = sksec->sclass; 4462 4463 selinux_netlbl_sk_security_reset(newsksec); 4464} 4465 4466static void selinux_sk_getsecid(struct sock *sk, u32 *secid) 4467{ 4468 if (!sk) 4469 *secid = SECINITSID_ANY_SOCKET; 4470 else { 4471 struct sk_security_struct *sksec = sk->sk_security; 4472 4473 *secid = sksec->sid; 4474 } 4475} 4476 4477static void selinux_sock_graft(struct sock *sk, struct socket *parent) 4478{ 4479 struct inode_security_struct *isec = SOCK_INODE(parent)->i_security; 4480 struct sk_security_struct *sksec = sk->sk_security; 4481 4482 if (sk->sk_family == PF_INET || sk->sk_family == PF_INET6 || 4483 sk->sk_family == PF_UNIX) 4484 isec->sid = sksec->sid; 4485 sksec->sclass = isec->sclass; 4486} 4487 4488static int selinux_inet_conn_request(struct sock *sk, struct sk_buff *skb, 4489 struct request_sock *req) 4490{ 4491 struct sk_security_struct *sksec = sk->sk_security; 4492 int err; 4493 u16 family = req->rsk_ops->family; 4494 u32 connsid; 4495 u32 peersid; 4496 4497 err = selinux_skb_peerlbl_sid(skb, family, &peersid); 4498 if (err) 4499 return err; 4500 err = selinux_conn_sid(sksec->sid, peersid, &connsid); 4501 if (err) 4502 return err; 4503 req->secid = connsid; 4504 req->peer_secid = peersid; 4505 4506 return selinux_netlbl_inet_conn_request(req, family); 4507} 4508 4509static void selinux_inet_csk_clone(struct sock *newsk, 4510 const struct request_sock *req) 4511{ 4512 struct sk_security_struct *newsksec = newsk->sk_security; 4513 4514 newsksec->sid = req->secid; 4515 newsksec->peer_sid = req->peer_secid; 4516 /* NOTE: Ideally, we should also get the isec->sid for the 4517 new socket in sync, but we don't have the isec available yet. 4518 So we will wait until sock_graft to do it, by which 4519 time it will have been created and available. */ 4520 4521 /* We don't need to take any sort of lock here as we are the only 4522 * thread with access to newsksec */ 4523 selinux_netlbl_inet_csk_clone(newsk, req->rsk_ops->family); 4524} 4525 4526static void selinux_inet_conn_established(struct sock *sk, struct sk_buff *skb) 4527{ 4528 u16 family = sk->sk_family; 4529 struct sk_security_struct *sksec = sk->sk_security; 4530 4531 /* handle mapped IPv4 packets arriving via IPv6 sockets */ 4532 if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP)) 4533 family = PF_INET; 4534 4535 selinux_skb_peerlbl_sid(skb, family, &sksec->peer_sid); 4536} 4537 4538static void selinux_skb_owned_by(struct sk_buff *skb, struct sock *sk) 4539{ 4540 skb_set_owner_w(skb, sk); 4541} 4542 4543static int selinux_secmark_relabel_packet(u32 sid) 4544{ 4545 const struct task_security_struct *__tsec; 4546 u32 tsid; 4547 4548 __tsec = current_security(); 4549 tsid = __tsec->sid; 4550 4551 return avc_has_perm(tsid, sid, SECCLASS_PACKET, PACKET__RELABELTO, NULL); 4552} 4553 4554static void selinux_secmark_refcount_inc(void) 4555{ 4556 atomic_inc(&selinux_secmark_refcount); 4557} 4558 4559static void selinux_secmark_refcount_dec(void) 4560{ 4561 atomic_dec(&selinux_secmark_refcount); 4562} 4563 4564static void selinux_req_classify_flow(const struct request_sock *req, 4565 struct flowi *fl) 4566{ 4567 fl->flowi_secid = req->secid; 4568} 4569 4570static int selinux_tun_dev_alloc_security(void **security) 4571{ 4572 struct tun_security_struct *tunsec; 4573 4574 tunsec = kzalloc(sizeof(*tunsec), GFP_KERNEL); 4575 if (!tunsec) 4576 return -ENOMEM; 4577 tunsec->sid = current_sid(); 4578 4579 *security = tunsec; 4580 return 0; 4581} 4582 4583static void selinux_tun_dev_free_security(void *security) 4584{ 4585 kfree(security); 4586} 4587 4588static int selinux_tun_dev_create(void) 4589{ 4590 u32 sid = current_sid(); 4591 4592 /* we aren't taking into account the "sockcreate" SID since the socket 4593 * that is being created here is not a socket in the traditional sense, 4594 * instead it is a private sock, accessible only to the kernel, and 4595 * representing a wide range of network traffic spanning multiple 4596 * connections unlike traditional sockets - check the TUN driver to 4597 * get a better understanding of why this socket is special */ 4598 4599 return avc_has_perm(sid, sid, SECCLASS_TUN_SOCKET, TUN_SOCKET__CREATE, 4600 NULL); 4601} 4602 4603static int selinux_tun_dev_attach_queue(void *security) 4604{ 4605 struct tun_security_struct *tunsec = security; 4606 4607 return avc_has_perm(current_sid(), tunsec->sid, SECCLASS_TUN_SOCKET, 4608 TUN_SOCKET__ATTACH_QUEUE, NULL); 4609} 4610 4611static int selinux_tun_dev_attach(struct sock *sk, void *security) 4612{ 4613 struct tun_security_struct *tunsec = security; 4614 struct sk_security_struct *sksec = sk->sk_security; 4615 4616 /* we don't currently perform any NetLabel based labeling here and it 4617 * isn't clear that we would want to do so anyway; while we could apply 4618 * labeling without the support of the TUN user the resulting labeled 4619 * traffic from the other end of the connection would almost certainly 4620 * cause confusion to the TUN user that had no idea network labeling 4621 * protocols were being used */ 4622 4623 sksec->sid = tunsec->sid; 4624 sksec->sclass = SECCLASS_TUN_SOCKET; 4625 4626 return 0; 4627} 4628 4629static int selinux_tun_dev_open(void *security) 4630{ 4631 struct tun_security_struct *tunsec = security; 4632 u32 sid = current_sid(); 4633 int err; 4634 4635 err = avc_has_perm(sid, tunsec->sid, SECCLASS_TUN_SOCKET, 4636 TUN_SOCKET__RELABELFROM, NULL); 4637 if (err) 4638 return err; 4639 err = avc_has_perm(sid, sid, SECCLASS_TUN_SOCKET, 4640 TUN_SOCKET__RELABELTO, NULL); 4641 if (err) 4642 return err; 4643 tunsec->sid = sid; 4644 4645 return 0; 4646} 4647 4648static int selinux_nlmsg_perm(struct sock *sk, struct sk_buff *skb) 4649{ 4650 int err = 0; 4651 u32 perm; 4652 struct nlmsghdr *nlh; 4653 struct sk_security_struct *sksec = sk->sk_security; 4654 4655 if (skb->len < NLMSG_HDRLEN) { 4656 err = -EINVAL; 4657 goto out; 4658 } 4659 nlh = nlmsg_hdr(skb); 4660 4661 err = selinux_nlmsg_lookup(sksec->sclass, nlh->nlmsg_type, &perm); 4662 if (err) { 4663 if (err == -EINVAL) { 4664 audit_log(current->audit_context, GFP_KERNEL, AUDIT_SELINUX_ERR, 4665 "SELinux: unrecognized netlink message" 4666 " type=%hu for sclass=%hu\n", 4667 nlh->nlmsg_type, sksec->sclass); 4668 if (!selinux_enforcing || security_get_allow_unknown()) 4669 err = 0; 4670 } 4671 4672 /* Ignore */ 4673 if (err == -ENOENT) 4674 err = 0; 4675 goto out; 4676 } 4677 4678 err = sock_has_perm(current, sk, perm); 4679out: 4680 return err; 4681} 4682 4683#ifdef CONFIG_NETFILTER 4684 4685static unsigned int selinux_ip_forward(struct sk_buff *skb, int ifindex, 4686 u16 family) 4687{ 4688 int err; 4689 char *addrp; 4690 u32 peer_sid; 4691 struct common_audit_data ad; 4692 struct lsm_network_audit net = {0,}; 4693 u8 secmark_active; 4694 u8 netlbl_active; 4695 u8 peerlbl_active; 4696 4697 if (!selinux_policycap_netpeer) 4698 return NF_ACCEPT; 4699 4700 secmark_active = selinux_secmark_enabled(); 4701 netlbl_active = netlbl_enabled(); 4702 peerlbl_active = selinux_peerlbl_enabled(); 4703 if (!secmark_active && !peerlbl_active) 4704 return NF_ACCEPT; 4705 4706 if (selinux_skb_peerlbl_sid(skb, family, &peer_sid) != 0) 4707 return NF_DROP; 4708 4709 ad.type = LSM_AUDIT_DATA_NET; 4710 ad.u.net = &net; 4711 ad.u.net->netif = ifindex; 4712 ad.u.net->family = family; 4713 if (selinux_parse_skb(skb, &ad, &addrp, 1, NULL) != 0) 4714 return NF_DROP; 4715 4716 if (peerlbl_active) { 4717 err = selinux_inet_sys_rcv_skb(ifindex, addrp, family, 4718 peer_sid, &ad); 4719 if (err) { 4720 selinux_netlbl_err(skb, err, 1); 4721 return NF_DROP; 4722 } 4723 } 4724 4725 if (secmark_active) 4726 if (avc_has_perm(peer_sid, skb->secmark, 4727 SECCLASS_PACKET, PACKET__FORWARD_IN, &ad)) 4728 return NF_DROP; 4729 4730 if (netlbl_active) 4731 /* we do this in the FORWARD path and not the POST_ROUTING 4732 * path because we want to make sure we apply the necessary 4733 * labeling before IPsec is applied so we can leverage AH 4734 * protection */ 4735 if (selinux_netlbl_skbuff_setsid(skb, family, peer_sid) != 0) 4736 return NF_DROP; 4737 4738 return NF_ACCEPT; 4739} 4740 4741static unsigned int selinux_ipv4_forward(const struct nf_hook_ops *ops, 4742 struct sk_buff *skb, 4743 const struct net_device *in, 4744 const struct net_device *out, 4745 int (*okfn)(struct sk_buff *)) 4746{ 4747 return selinux_ip_forward(skb, in->ifindex, PF_INET); 4748} 4749 4750#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE) 4751static unsigned int selinux_ipv6_forward(const struct nf_hook_ops *ops, 4752 struct sk_buff *skb, 4753 const struct net_device *in, 4754 const struct net_device *out, 4755 int (*okfn)(struct sk_buff *)) 4756{ 4757 return selinux_ip_forward(skb, in->ifindex, PF_INET6); 4758} 4759#endif /* IPV6 */ 4760 4761static unsigned int selinux_ip_output(struct sk_buff *skb, 4762 u16 family) 4763{ 4764 struct sock *sk; 4765 u32 sid; 4766 4767 if (!netlbl_enabled()) 4768 return NF_ACCEPT; 4769 4770 /* we do this in the LOCAL_OUT path and not the POST_ROUTING path 4771 * because we want to make sure we apply the necessary labeling 4772 * before IPsec is applied so we can leverage AH protection */ 4773 sk = skb->sk; 4774 if (sk) { 4775 struct sk_security_struct *sksec; 4776 4777 if (sk->sk_state == TCP_LISTEN) 4778 /* if the socket is the listening state then this 4779 * packet is a SYN-ACK packet which means it needs to 4780 * be labeled based on the connection/request_sock and 4781 * not the parent socket. unfortunately, we can't 4782 * lookup the request_sock yet as it isn't queued on 4783 * the parent socket until after the SYN-ACK is sent. 4784 * the "solution" is to simply pass the packet as-is 4785 * as any IP option based labeling should be copied 4786 * from the initial connection request (in the IP 4787 * layer). it is far from ideal, but until we get a 4788 * security label in the packet itself this is the 4789 * best we can do. */ 4790 return NF_ACCEPT; 4791 4792 /* standard practice, label using the parent socket */ 4793 sksec = sk->sk_security; 4794 sid = sksec->sid; 4795 } else 4796 sid = SECINITSID_KERNEL; 4797 if (selinux_netlbl_skbuff_setsid(skb, family, sid) != 0) 4798 return NF_DROP; 4799 4800 return NF_ACCEPT; 4801} 4802 4803static unsigned int selinux_ipv4_output(const struct nf_hook_ops *ops, 4804 struct sk_buff *skb, 4805 const struct net_device *in, 4806 const struct net_device *out, 4807 int (*okfn)(struct sk_buff *)) 4808{ 4809 return selinux_ip_output(skb, PF_INET); 4810} 4811 4812static unsigned int selinux_ip_postroute_compat(struct sk_buff *skb, 4813 int ifindex, 4814 u16 family) 4815{ 4816 struct sock *sk = skb->sk; 4817 struct sk_security_struct *sksec; 4818 struct common_audit_data ad; 4819 struct lsm_network_audit net = {0,}; 4820 char *addrp; 4821 u8 proto; 4822 4823 if (sk == NULL) 4824 return NF_ACCEPT; 4825 sksec = sk->sk_security; 4826 4827 ad.type = LSM_AUDIT_DATA_NET; 4828 ad.u.net = &net; 4829 ad.u.net->netif = ifindex; 4830 ad.u.net->family = family; 4831 if (selinux_parse_skb(skb, &ad, &addrp, 0, &proto)) 4832 return NF_DROP; 4833 4834 if (selinux_secmark_enabled()) 4835 if (avc_has_perm(sksec->sid, skb->secmark, 4836 SECCLASS_PACKET, PACKET__SEND, &ad)) 4837 return NF_DROP_ERR(-ECONNREFUSED); 4838 4839 if (selinux_xfrm_postroute_last(sksec->sid, skb, &ad, proto)) 4840 return NF_DROP_ERR(-ECONNREFUSED); 4841 4842 return NF_ACCEPT; 4843} 4844 4845static unsigned int selinux_ip_postroute(struct sk_buff *skb, int ifindex, 4846 u16 family) 4847{ 4848 u32 secmark_perm; 4849 u32 peer_sid; 4850 struct sock *sk; 4851 struct common_audit_data ad; 4852 struct lsm_network_audit net = {0,}; 4853 char *addrp; 4854 u8 secmark_active; 4855 u8 peerlbl_active; 4856 4857 /* If any sort of compatibility mode is enabled then handoff processing 4858 * to the selinux_ip_postroute_compat() function to deal with the 4859 * special handling. We do this in an attempt to keep this function 4860 * as fast and as clean as possible. */ 4861 if (!selinux_policycap_netpeer) 4862 return selinux_ip_postroute_compat(skb, ifindex, family); 4863 4864 secmark_active = selinux_secmark_enabled(); 4865 peerlbl_active = selinux_peerlbl_enabled(); 4866 if (!secmark_active && !peerlbl_active) 4867 return NF_ACCEPT; 4868 4869 sk = skb->sk; 4870 4871#ifdef CONFIG_XFRM 4872 /* If skb->dst->xfrm is non-NULL then the packet is undergoing an IPsec 4873 * packet transformation so allow the packet to pass without any checks 4874 * since we'll have another chance to perform access control checks 4875 * when the packet is on it's final way out. 4876 * NOTE: there appear to be some IPv6 multicast cases where skb->dst 4877 * is NULL, in this case go ahead and apply access control. 4878 * NOTE: if this is a local socket (skb->sk != NULL) that is in the 4879 * TCP listening state we cannot wait until the XFRM processing 4880 * is done as we will miss out on the SA label if we do; 4881 * unfortunately, this means more work, but it is only once per 4882 * connection. */ 4883 if (skb_dst(skb) != NULL && skb_dst(skb)->xfrm != NULL && 4884 !(sk != NULL && sk->sk_state == TCP_LISTEN)) 4885 return NF_ACCEPT; 4886#endif 4887 4888 if (sk == NULL) { 4889 /* Without an associated socket the packet is either coming 4890 * from the kernel or it is being forwarded; check the packet 4891 * to determine which and if the packet is being forwarded 4892 * query the packet directly to determine the security label. */ 4893 if (skb->skb_iif) { 4894 secmark_perm = PACKET__FORWARD_OUT; 4895 if (selinux_skb_peerlbl_sid(skb, family, &peer_sid)) 4896 return NF_DROP; 4897 } else { 4898 secmark_perm = PACKET__SEND; 4899 peer_sid = SECINITSID_KERNEL; 4900 } 4901 } else if (sk->sk_state == TCP_LISTEN) { 4902 /* Locally generated packet but the associated socket is in the 4903 * listening state which means this is a SYN-ACK packet. In 4904 * this particular case the correct security label is assigned 4905 * to the connection/request_sock but unfortunately we can't 4906 * query the request_sock as it isn't queued on the parent 4907 * socket until after the SYN-ACK packet is sent; the only 4908 * viable choice is to regenerate the label like we do in 4909 * selinux_inet_conn_request(). See also selinux_ip_output() 4910 * for similar problems. */ 4911 u32 skb_sid; 4912 struct sk_security_struct *sksec = sk->sk_security; 4913 if (selinux_skb_peerlbl_sid(skb, family, &skb_sid)) 4914 return NF_DROP; 4915 /* At this point, if the returned skb peerlbl is SECSID_NULL 4916 * and the packet has been through at least one XFRM 4917 * transformation then we must be dealing with the "final" 4918 * form of labeled IPsec packet; since we've already applied 4919 * all of our access controls on this packet we can safely 4920 * pass the packet. */ 4921 if (skb_sid == SECSID_NULL) { 4922 switch (family) { 4923 case PF_INET: 4924 if (IPCB(skb)->flags & IPSKB_XFRM_TRANSFORMED) 4925 return NF_ACCEPT; 4926 break; 4927 case PF_INET6: 4928 if (IP6CB(skb)->flags & IP6SKB_XFRM_TRANSFORMED) 4929 return NF_ACCEPT; 4930 default: 4931 return NF_DROP_ERR(-ECONNREFUSED); 4932 } 4933 } 4934 if (selinux_conn_sid(sksec->sid, skb_sid, &peer_sid)) 4935 return NF_DROP; 4936 secmark_perm = PACKET__SEND; 4937 } else { 4938 /* Locally generated packet, fetch the security label from the 4939 * associated socket. */ 4940 struct sk_security_struct *sksec = sk->sk_security; 4941 peer_sid = sksec->sid; 4942 secmark_perm = PACKET__SEND; 4943 } 4944 4945 ad.type = LSM_AUDIT_DATA_NET; 4946 ad.u.net = &net; 4947 ad.u.net->netif = ifindex; 4948 ad.u.net->family = family; 4949 if (selinux_parse_skb(skb, &ad, &addrp, 0, NULL)) 4950 return NF_DROP; 4951 4952 if (secmark_active) 4953 if (avc_has_perm(peer_sid, skb->secmark, 4954 SECCLASS_PACKET, secmark_perm, &ad)) 4955 return NF_DROP_ERR(-ECONNREFUSED); 4956 4957 if (peerlbl_active) { 4958 u32 if_sid; 4959 u32 node_sid; 4960 4961 if (sel_netif_sid(ifindex, &if_sid)) 4962 return NF_DROP; 4963 if (avc_has_perm(peer_sid, if_sid, 4964 SECCLASS_NETIF, NETIF__EGRESS, &ad)) 4965 return NF_DROP_ERR(-ECONNREFUSED); 4966 4967 if (sel_netnode_sid(addrp, family, &node_sid)) 4968 return NF_DROP; 4969 if (avc_has_perm(peer_sid, node_sid, 4970 SECCLASS_NODE, NODE__SENDTO, &ad)) 4971 return NF_DROP_ERR(-ECONNREFUSED); 4972 } 4973 4974 return NF_ACCEPT; 4975} 4976 4977static unsigned int selinux_ipv4_postroute(const struct nf_hook_ops *ops, 4978 struct sk_buff *skb, 4979 const struct net_device *in, 4980 const struct net_device *out, 4981 int (*okfn)(struct sk_buff *)) 4982{ 4983 return selinux_ip_postroute(skb, out->ifindex, PF_INET); 4984} 4985 4986#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE) 4987static unsigned int selinux_ipv6_postroute(const struct nf_hook_ops *ops, 4988 struct sk_buff *skb, 4989 const struct net_device *in, 4990 const struct net_device *out, 4991 int (*okfn)(struct sk_buff *)) 4992{ 4993 return selinux_ip_postroute(skb, out->ifindex, PF_INET6); 4994} 4995#endif /* IPV6 */ 4996 4997#endif /* CONFIG_NETFILTER */ 4998 4999static int selinux_netlink_send(struct sock *sk, struct sk_buff *skb) 5000{ 5001 int err; 5002 5003 err = cap_netlink_send(sk, skb); 5004 if (err) 5005 return err; 5006 5007 return selinux_nlmsg_perm(sk, skb); 5008} 5009 5010static int ipc_alloc_security(struct task_struct *task, 5011 struct kern_ipc_perm *perm, 5012 u16 sclass) 5013{ 5014 struct ipc_security_struct *isec; 5015 u32 sid; 5016 5017 isec = kzalloc(sizeof(struct ipc_security_struct), GFP_KERNEL); 5018 if (!isec) 5019 return -ENOMEM; 5020 5021 sid = task_sid(task); 5022 isec->sclass = sclass; 5023 isec->sid = sid; 5024 perm->security = isec; 5025 5026 return 0; 5027} 5028 5029static void ipc_free_security(struct kern_ipc_perm *perm) 5030{ 5031 struct ipc_security_struct *isec = perm->security; 5032 perm->security = NULL; 5033 kfree(isec); 5034} 5035 5036static int msg_msg_alloc_security(struct msg_msg *msg) 5037{ 5038 struct msg_security_struct *msec; 5039 5040 msec = kzalloc(sizeof(struct msg_security_struct), GFP_KERNEL); 5041 if (!msec) 5042 return -ENOMEM; 5043 5044 msec->sid = SECINITSID_UNLABELED; 5045 msg->security = msec; 5046 5047 return 0; 5048} 5049 5050static void msg_msg_free_security(struct msg_msg *msg) 5051{ 5052 struct msg_security_struct *msec = msg->security; 5053 5054 msg->security = NULL; 5055 kfree(msec); 5056} 5057 5058static int ipc_has_perm(struct kern_ipc_perm *ipc_perms, 5059 u32 perms) 5060{ 5061 struct ipc_security_struct *isec; 5062 struct common_audit_data ad; 5063 u32 sid = current_sid(); 5064 5065 isec = ipc_perms->security; 5066 5067 ad.type = LSM_AUDIT_DATA_IPC; 5068 ad.u.ipc_id = ipc_perms->key; 5069 5070 return avc_has_perm(sid, isec->sid, isec->sclass, perms, &ad); 5071} 5072 5073static int selinux_msg_msg_alloc_security(struct msg_msg *msg) 5074{ 5075 return msg_msg_alloc_security(msg); 5076} 5077 5078static void selinux_msg_msg_free_security(struct msg_msg *msg) 5079{ 5080 msg_msg_free_security(msg); 5081} 5082 5083/* message queue security operations */ 5084static int selinux_msg_queue_alloc_security(struct msg_queue *msq) 5085{ 5086 struct ipc_security_struct *isec; 5087 struct common_audit_data ad; 5088 u32 sid = current_sid(); 5089 int rc; 5090 5091 rc = ipc_alloc_security(current, &msq->q_perm, SECCLASS_MSGQ); 5092 if (rc) 5093 return rc; 5094 5095 isec = msq->q_perm.security; 5096 5097 ad.type = LSM_AUDIT_DATA_IPC; 5098 ad.u.ipc_id = msq->q_perm.key; 5099 5100 rc = avc_has_perm(sid, isec->sid, SECCLASS_MSGQ, 5101 MSGQ__CREATE, &ad); 5102 if (rc) { 5103 ipc_free_security(&msq->q_perm); 5104 return rc; 5105 } 5106 return 0; 5107} 5108 5109static void selinux_msg_queue_free_security(struct msg_queue *msq) 5110{ 5111 ipc_free_security(&msq->q_perm); 5112} 5113 5114static int selinux_msg_queue_associate(struct msg_queue *msq, int msqflg) 5115{ 5116 struct ipc_security_struct *isec; 5117 struct common_audit_data ad; 5118 u32 sid = current_sid(); 5119 5120 isec = msq->q_perm.security; 5121 5122 ad.type = LSM_AUDIT_DATA_IPC; 5123 ad.u.ipc_id = msq->q_perm.key; 5124 5125 return avc_has_perm(sid, isec->sid, SECCLASS_MSGQ, 5126 MSGQ__ASSOCIATE, &ad); 5127} 5128 5129static int selinux_msg_queue_msgctl(struct msg_queue *msq, int cmd) 5130{ 5131 int err; 5132 int perms; 5133 5134 switch (cmd) { 5135 case IPC_INFO: 5136 case MSG_INFO: 5137 /* No specific object, just general system-wide information. */ 5138 return task_has_system(current, SYSTEM__IPC_INFO); 5139 case IPC_STAT: 5140 case MSG_STAT: 5141 perms = MSGQ__GETATTR | MSGQ__ASSOCIATE; 5142 break; 5143 case IPC_SET: 5144 perms = MSGQ__SETATTR; 5145 break; 5146 case IPC_RMID: 5147 perms = MSGQ__DESTROY; 5148 break; 5149 default: 5150 return 0; 5151 } 5152 5153 err = ipc_has_perm(&msq->q_perm, perms); 5154 return err; 5155} 5156 5157static int selinux_msg_queue_msgsnd(struct msg_queue *msq, struct msg_msg *msg, int msqflg) 5158{ 5159 struct ipc_security_struct *isec; 5160 struct msg_security_struct *msec; 5161 struct common_audit_data ad; 5162 u32 sid = current_sid(); 5163 int rc; 5164 5165 isec = msq->q_perm.security; 5166 msec = msg->security; 5167 5168 /* 5169 * First time through, need to assign label to the message 5170 */ 5171 if (msec->sid == SECINITSID_UNLABELED) { 5172 /* 5173 * Compute new sid based on current process and 5174 * message queue this message will be stored in 5175 */ 5176 rc = security_transition_sid(sid, isec->sid, SECCLASS_MSG, 5177 NULL, &msec->sid); 5178 if (rc) 5179 return rc; 5180 } 5181 5182 ad.type = LSM_AUDIT_DATA_IPC; 5183 ad.u.ipc_id = msq->q_perm.key; 5184 5185 /* Can this process write to the queue? */ 5186 rc = avc_has_perm(sid, isec->sid, SECCLASS_MSGQ, 5187 MSGQ__WRITE, &ad); 5188 if (!rc) 5189 /* Can this process send the message */ 5190 rc = avc_has_perm(sid, msec->sid, SECCLASS_MSG, 5191 MSG__SEND, &ad); 5192 if (!rc) 5193 /* Can the message be put in the queue? */ 5194 rc = avc_has_perm(msec->sid, isec->sid, SECCLASS_MSGQ, 5195 MSGQ__ENQUEUE, &ad); 5196 5197 return rc; 5198} 5199 5200static int selinux_msg_queue_msgrcv(struct msg_queue *msq, struct msg_msg *msg, 5201 struct task_struct *target, 5202 long type, int mode) 5203{ 5204 struct ipc_security_struct *isec; 5205 struct msg_security_struct *msec; 5206 struct common_audit_data ad; 5207 u32 sid = task_sid(target); 5208 int rc; 5209 5210 isec = msq->q_perm.security; 5211 msec = msg->security; 5212 5213 ad.type = LSM_AUDIT_DATA_IPC; 5214 ad.u.ipc_id = msq->q_perm.key; 5215 5216 rc = avc_has_perm(sid, isec->sid, 5217 SECCLASS_MSGQ, MSGQ__READ, &ad); 5218 if (!rc) 5219 rc = avc_has_perm(sid, msec->sid, 5220 SECCLASS_MSG, MSG__RECEIVE, &ad); 5221 return rc; 5222} 5223 5224/* Shared Memory security operations */ 5225static int selinux_shm_alloc_security(struct shmid_kernel *shp) 5226{ 5227 struct ipc_security_struct *isec; 5228 struct common_audit_data ad; 5229 u32 sid = current_sid(); 5230 int rc; 5231 5232 rc = ipc_alloc_security(current, &shp->shm_perm, SECCLASS_SHM); 5233 if (rc) 5234 return rc; 5235 5236 isec = shp->shm_perm.security; 5237 5238 ad.type = LSM_AUDIT_DATA_IPC; 5239 ad.u.ipc_id = shp->shm_perm.key; 5240 5241 rc = avc_has_perm(sid, isec->sid, SECCLASS_SHM, 5242 SHM__CREATE, &ad); 5243 if (rc) { 5244 ipc_free_security(&shp->shm_perm); 5245 return rc; 5246 } 5247 return 0; 5248} 5249 5250static void selinux_shm_free_security(struct shmid_kernel *shp) 5251{ 5252 ipc_free_security(&shp->shm_perm); 5253} 5254 5255static int selinux_shm_associate(struct shmid_kernel *shp, int shmflg) 5256{ 5257 struct ipc_security_struct *isec; 5258 struct common_audit_data ad; 5259 u32 sid = current_sid(); 5260 5261 isec = shp->shm_perm.security; 5262 5263 ad.type = LSM_AUDIT_DATA_IPC; 5264 ad.u.ipc_id = shp->shm_perm.key; 5265 5266 return avc_has_perm(sid, isec->sid, SECCLASS_SHM, 5267 SHM__ASSOCIATE, &ad); 5268} 5269 5270/* Note, at this point, shp is locked down */ 5271static int selinux_shm_shmctl(struct shmid_kernel *shp, int cmd) 5272{ 5273 int perms; 5274 int err; 5275 5276 switch (cmd) { 5277 case IPC_INFO: 5278 case SHM_INFO: 5279 /* No specific object, just general system-wide information. */ 5280 return task_has_system(current, SYSTEM__IPC_INFO); 5281 case IPC_STAT: 5282 case SHM_STAT: 5283 perms = SHM__GETATTR | SHM__ASSOCIATE; 5284 break; 5285 case IPC_SET: 5286 perms = SHM__SETATTR; 5287 break; 5288 case SHM_LOCK: 5289 case SHM_UNLOCK: 5290 perms = SHM__LOCK; 5291 break; 5292 case IPC_RMID: 5293 perms = SHM__DESTROY; 5294 break; 5295 default: 5296 return 0; 5297 } 5298 5299 err = ipc_has_perm(&shp->shm_perm, perms); 5300 return err; 5301} 5302 5303static int selinux_shm_shmat(struct shmid_kernel *shp, 5304 char __user *shmaddr, int shmflg) 5305{ 5306 u32 perms; 5307 5308 if (shmflg & SHM_RDONLY) 5309 perms = SHM__READ; 5310 else 5311 perms = SHM__READ | SHM__WRITE; 5312 5313 return ipc_has_perm(&shp->shm_perm, perms); 5314} 5315 5316/* Semaphore security operations */ 5317static int selinux_sem_alloc_security(struct sem_array *sma) 5318{ 5319 struct ipc_security_struct *isec; 5320 struct common_audit_data ad; 5321 u32 sid = current_sid(); 5322 int rc; 5323 5324 rc = ipc_alloc_security(current, &sma->sem_perm, SECCLASS_SEM); 5325 if (rc) 5326 return rc; 5327 5328 isec = sma->sem_perm.security; 5329 5330 ad.type = LSM_AUDIT_DATA_IPC; 5331 ad.u.ipc_id = sma->sem_perm.key; 5332 5333 rc = avc_has_perm(sid, isec->sid, SECCLASS_SEM, 5334 SEM__CREATE, &ad); 5335 if (rc) { 5336 ipc_free_security(&sma->sem_perm); 5337 return rc; 5338 } 5339 return 0; 5340} 5341 5342static void selinux_sem_free_security(struct sem_array *sma) 5343{ 5344 ipc_free_security(&sma->sem_perm); 5345} 5346 5347static int selinux_sem_associate(struct sem_array *sma, int semflg) 5348{ 5349 struct ipc_security_struct *isec; 5350 struct common_audit_data ad; 5351 u32 sid = current_sid(); 5352 5353 isec = sma->sem_perm.security; 5354 5355 ad.type = LSM_AUDIT_DATA_IPC; 5356 ad.u.ipc_id = sma->sem_perm.key; 5357 5358 return avc_has_perm(sid, isec->sid, SECCLASS_SEM, 5359 SEM__ASSOCIATE, &ad); 5360} 5361 5362/* Note, at this point, sma is locked down */ 5363static int selinux_sem_semctl(struct sem_array *sma, int cmd) 5364{ 5365 int err; 5366 u32 perms; 5367 5368 switch (cmd) { 5369 case IPC_INFO: 5370 case SEM_INFO: 5371 /* No specific object, just general system-wide information. */ 5372 return task_has_system(current, SYSTEM__IPC_INFO); 5373 case GETPID: 5374 case GETNCNT: 5375 case GETZCNT: 5376 perms = SEM__GETATTR; 5377 break; 5378 case GETVAL: 5379 case GETALL: 5380 perms = SEM__READ; 5381 break; 5382 case SETVAL: 5383 case SETALL: 5384 perms = SEM__WRITE; 5385 break; 5386 case IPC_RMID: 5387 perms = SEM__DESTROY; 5388 break; 5389 case IPC_SET: 5390 perms = SEM__SETATTR; 5391 break; 5392 case IPC_STAT: 5393 case SEM_STAT: 5394 perms = SEM__GETATTR | SEM__ASSOCIATE; 5395 break; 5396 default: 5397 return 0; 5398 } 5399 5400 err = ipc_has_perm(&sma->sem_perm, perms); 5401 return err; 5402} 5403 5404static int selinux_sem_semop(struct sem_array *sma, 5405 struct sembuf *sops, unsigned nsops, int alter) 5406{ 5407 u32 perms; 5408 5409 if (alter) 5410 perms = SEM__READ | SEM__WRITE; 5411 else 5412 perms = SEM__READ; 5413 5414 return ipc_has_perm(&sma->sem_perm, perms); 5415} 5416 5417static int selinux_ipc_permission(struct kern_ipc_perm *ipcp, short flag) 5418{ 5419 u32 av = 0; 5420 5421 av = 0; 5422 if (flag & S_IRUGO) 5423 av |= IPC__UNIX_READ; 5424 if (flag & S_IWUGO) 5425 av |= IPC__UNIX_WRITE; 5426 5427 if (av == 0) 5428 return 0; 5429 5430 return ipc_has_perm(ipcp, av); 5431} 5432 5433static void selinux_ipc_getsecid(struct kern_ipc_perm *ipcp, u32 *secid) 5434{ 5435 struct ipc_security_struct *isec = ipcp->security; 5436 *secid = isec->sid; 5437} 5438 5439static void selinux_d_instantiate(struct dentry *dentry, struct inode *inode) 5440{ 5441 if (inode) 5442 inode_doinit_with_dentry(inode, dentry); 5443} 5444 5445static int selinux_getprocattr(struct task_struct *p, 5446 char *name, char **value) 5447{ 5448 const struct task_security_struct *__tsec; 5449 u32 sid; 5450 int error; 5451 unsigned len; 5452 5453 if (current != p) { 5454 error = current_has_perm(p, PROCESS__GETATTR); 5455 if (error) 5456 return error; 5457 } 5458 5459 rcu_read_lock(); 5460 __tsec = __task_cred(p)->security; 5461 5462 if (!strcmp(name, "current")) 5463 sid = __tsec->sid; 5464 else if (!strcmp(name, "prev")) 5465 sid = __tsec->osid; 5466 else if (!strcmp(name, "exec")) 5467 sid = __tsec->exec_sid; 5468 else if (!strcmp(name, "fscreate")) 5469 sid = __tsec->create_sid; 5470 else if (!strcmp(name, "keycreate")) 5471 sid = __tsec->keycreate_sid; 5472 else if (!strcmp(name, "sockcreate")) 5473 sid = __tsec->sockcreate_sid; 5474 else 5475 goto invalid; 5476 rcu_read_unlock(); 5477 5478 if (!sid) 5479 return 0; 5480 5481 error = security_sid_to_context(sid, value, &len); 5482 if (error) 5483 return error; 5484 return len; 5485 5486invalid: 5487 rcu_read_unlock(); 5488 return -EINVAL; 5489} 5490 5491static int selinux_setprocattr(struct task_struct *p, 5492 char *name, void *value, size_t size) 5493{ 5494 struct task_security_struct *tsec; 5495 struct task_struct *tracer; 5496 struct cred *new; 5497 u32 sid = 0, ptsid; 5498 int error; 5499 char *str = value; 5500 5501 if (current != p) { 5502 /* SELinux only allows a process to change its own 5503 security attributes. */ 5504 return -EACCES; 5505 } 5506 5507 /* 5508 * Basic control over ability to set these attributes at all. 5509 * current == p, but we'll pass them separately in case the 5510 * above restriction is ever removed. 5511 */ 5512 if (!strcmp(name, "exec")) 5513 error = current_has_perm(p, PROCESS__SETEXEC); 5514 else if (!strcmp(name, "fscreate")) 5515 error = current_has_perm(p, PROCESS__SETFSCREATE); 5516 else if (!strcmp(name, "keycreate")) 5517 error = current_has_perm(p, PROCESS__SETKEYCREATE); 5518 else if (!strcmp(name, "sockcreate")) 5519 error = current_has_perm(p, PROCESS__SETSOCKCREATE); 5520 else if (!strcmp(name, "current")) 5521 error = current_has_perm(p, PROCESS__SETCURRENT); 5522 else 5523 error = -EINVAL; 5524 if (error) 5525 return error; 5526 5527 /* Obtain a SID for the context, if one was specified. */ 5528 if (size && str[1] && str[1] != '\n') { 5529 if (str[size-1] == '\n') { 5530 str[size-1] = 0; 5531 size--; 5532 } 5533 error = security_context_to_sid(value, size, &sid, GFP_KERNEL); 5534 if (error == -EINVAL && !strcmp(name, "fscreate")) { 5535 if (!capable(CAP_MAC_ADMIN)) { 5536 struct audit_buffer *ab; 5537 size_t audit_size; 5538 5539 /* We strip a nul only if it is at the end, otherwise the 5540 * context contains a nul and we should audit that */ 5541 if (str[size - 1] == '\0') 5542 audit_size = size - 1; 5543 else 5544 audit_size = size; 5545 ab = audit_log_start(current->audit_context, GFP_ATOMIC, AUDIT_SELINUX_ERR); 5546 audit_log_format(ab, "op=fscreate invalid_context="); 5547 audit_log_n_untrustedstring(ab, value, audit_size); 5548 audit_log_end(ab); 5549 5550 return error; 5551 } 5552 error = security_context_to_sid_force(value, size, 5553 &sid); 5554 } 5555 if (error) 5556 return error; 5557 } 5558 5559 new = prepare_creds(); 5560 if (!new) 5561 return -ENOMEM; 5562 5563 /* Permission checking based on the specified context is 5564 performed during the actual operation (execve, 5565 open/mkdir/...), when we know the full context of the 5566 operation. See selinux_bprm_set_creds for the execve 5567 checks and may_create for the file creation checks. The 5568 operation will then fail if the context is not permitted. */ 5569 tsec = new->security; 5570 if (!strcmp(name, "exec")) { 5571 tsec->exec_sid = sid; 5572 } else if (!strcmp(name, "fscreate")) { 5573 tsec->create_sid = sid; 5574 } else if (!strcmp(name, "keycreate")) { 5575 error = may_create_key(sid, p); 5576 if (error) 5577 goto abort_change; 5578 tsec->keycreate_sid = sid; 5579 } else if (!strcmp(name, "sockcreate")) { 5580 tsec->sockcreate_sid = sid; 5581 } else if (!strcmp(name, "current")) { 5582 error = -EINVAL; 5583 if (sid == 0) 5584 goto abort_change; 5585 5586 /* Only allow single threaded processes to change context */ 5587 error = -EPERM; 5588 if (!current_is_single_threaded()) { 5589 error = security_bounded_transition(tsec->sid, sid); 5590 if (error) 5591 goto abort_change; 5592 } 5593 5594 /* Check permissions for the transition. */ 5595 error = avc_has_perm(tsec->sid, sid, SECCLASS_PROCESS, 5596 PROCESS__DYNTRANSITION, NULL); 5597 if (error) 5598 goto abort_change; 5599 5600 /* Check for ptracing, and update the task SID if ok. 5601 Otherwise, leave SID unchanged and fail. */ 5602 ptsid = 0; 5603 rcu_read_lock(); 5604 tracer = ptrace_parent(p); 5605 if (tracer) 5606 ptsid = task_sid(tracer); 5607 rcu_read_unlock(); 5608 5609 if (tracer) { 5610 error = avc_has_perm(ptsid, sid, SECCLASS_PROCESS, 5611 PROCESS__PTRACE, NULL); 5612 if (error) 5613 goto abort_change; 5614 } 5615 5616 tsec->sid = sid; 5617 } else { 5618 error = -EINVAL; 5619 goto abort_change; 5620 } 5621 5622 commit_creds(new); 5623 return size; 5624 5625abort_change: 5626 abort_creds(new); 5627 return error; 5628} 5629 5630static int selinux_ismaclabel(const char *name) 5631{ 5632 return (strcmp(name, XATTR_SELINUX_SUFFIX) == 0); 5633} 5634 5635static int selinux_secid_to_secctx(u32 secid, char **secdata, u32 *seclen) 5636{ 5637 return security_sid_to_context(secid, secdata, seclen); 5638} 5639 5640static int selinux_secctx_to_secid(const char *secdata, u32 seclen, u32 *secid) 5641{ 5642 return security_context_to_sid(secdata, seclen, secid, GFP_KERNEL); 5643} 5644 5645static void selinux_release_secctx(char *secdata, u32 seclen) 5646{ 5647 kfree(secdata); 5648} 5649 5650/* 5651 * called with inode->i_mutex locked 5652 */ 5653static int selinux_inode_notifysecctx(struct inode *inode, void *ctx, u32 ctxlen) 5654{ 5655 return selinux_inode_setsecurity(inode, XATTR_SELINUX_SUFFIX, ctx, ctxlen, 0); 5656} 5657 5658/* 5659 * called with inode->i_mutex locked 5660 */ 5661static int selinux_inode_setsecctx(struct dentry *dentry, void *ctx, u32 ctxlen) 5662{ 5663 return __vfs_setxattr_noperm(dentry, XATTR_NAME_SELINUX, ctx, ctxlen, 0); 5664} 5665 5666static int selinux_inode_getsecctx(struct inode *inode, void **ctx, u32 *ctxlen) 5667{ 5668 int len = 0; 5669 len = selinux_inode_getsecurity(inode, XATTR_SELINUX_SUFFIX, 5670 ctx, true); 5671 if (len < 0) 5672 return len; 5673 *ctxlen = len; 5674 return 0; 5675} 5676#ifdef CONFIG_KEYS 5677 5678static int selinux_key_alloc(struct key *k, const struct cred *cred, 5679 unsigned long flags) 5680{ 5681 const struct task_security_struct *tsec; 5682 struct key_security_struct *ksec; 5683 5684 ksec = kzalloc(sizeof(struct key_security_struct), GFP_KERNEL); 5685 if (!ksec) 5686 return -ENOMEM; 5687 5688 tsec = cred->security; 5689 if (tsec->keycreate_sid) 5690 ksec->sid = tsec->keycreate_sid; 5691 else 5692 ksec->sid = tsec->sid; 5693 5694 k->security = ksec; 5695 return 0; 5696} 5697 5698static void selinux_key_free(struct key *k) 5699{ 5700 struct key_security_struct *ksec = k->security; 5701 5702 k->security = NULL; 5703 kfree(ksec); 5704} 5705 5706static int selinux_key_permission(key_ref_t key_ref, 5707 const struct cred *cred, 5708 key_perm_t perm) 5709{ 5710 struct key *key; 5711 struct key_security_struct *ksec; 5712 u32 sid; 5713 5714 /* if no specific permissions are requested, we skip the 5715 permission check. No serious, additional covert channels 5716 appear to be created. */ 5717 if (perm == 0) 5718 return 0; 5719 5720 sid = cred_sid(cred); 5721 5722 key = key_ref_to_ptr(key_ref); 5723 ksec = key->security; 5724 5725 return avc_has_perm(sid, ksec->sid, SECCLASS_KEY, perm, NULL); 5726} 5727 5728static int selinux_key_getsecurity(struct key *key, char **_buffer) 5729{ 5730 struct key_security_struct *ksec = key->security; 5731 char *context = NULL; 5732 unsigned len; 5733 int rc; 5734 5735 rc = security_sid_to_context(ksec->sid, &context, &len); 5736 if (!rc) 5737 rc = len; 5738 *_buffer = context; 5739 return rc; 5740} 5741 5742#endif 5743 5744static struct security_operations selinux_ops = { 5745 .name = "selinux", 5746 5747 .ptrace_access_check = selinux_ptrace_access_check, 5748 .ptrace_traceme = selinux_ptrace_traceme, 5749 .capget = selinux_capget, 5750 .capset = selinux_capset, 5751 .capable = selinux_capable, 5752 .quotactl = selinux_quotactl, 5753 .quota_on = selinux_quota_on, 5754 .syslog = selinux_syslog, 5755 .vm_enough_memory = selinux_vm_enough_memory, 5756 5757 .netlink_send = selinux_netlink_send, 5758 5759 .bprm_set_creds = selinux_bprm_set_creds, 5760 .bprm_committing_creds = selinux_bprm_committing_creds, 5761 .bprm_committed_creds = selinux_bprm_committed_creds, 5762 .bprm_secureexec = selinux_bprm_secureexec, 5763 5764 .sb_alloc_security = selinux_sb_alloc_security, 5765 .sb_free_security = selinux_sb_free_security, 5766 .sb_copy_data = selinux_sb_copy_data, 5767 .sb_remount = selinux_sb_remount, 5768 .sb_kern_mount = selinux_sb_kern_mount, 5769 .sb_show_options = selinux_sb_show_options, 5770 .sb_statfs = selinux_sb_statfs, 5771 .sb_mount = selinux_mount, 5772 .sb_umount = selinux_umount, 5773 .sb_set_mnt_opts = selinux_set_mnt_opts, 5774 .sb_clone_mnt_opts = selinux_sb_clone_mnt_opts, 5775 .sb_parse_opts_str = selinux_parse_opts_str, 5776 5777 .dentry_init_security = selinux_dentry_init_security, 5778 5779 .inode_alloc_security = selinux_inode_alloc_security, 5780 .inode_free_security = selinux_inode_free_security, 5781 .inode_init_security = selinux_inode_init_security, 5782 .inode_create = selinux_inode_create, 5783 .inode_link = selinux_inode_link, 5784 .inode_unlink = selinux_inode_unlink, 5785 .inode_symlink = selinux_inode_symlink, 5786 .inode_mkdir = selinux_inode_mkdir, 5787 .inode_rmdir = selinux_inode_rmdir, 5788 .inode_mknod = selinux_inode_mknod, 5789 .inode_rename = selinux_inode_rename, 5790 .inode_readlink = selinux_inode_readlink, 5791 .inode_follow_link = selinux_inode_follow_link, 5792 .inode_permission = selinux_inode_permission, 5793 .inode_setattr = selinux_inode_setattr, 5794 .inode_getattr = selinux_inode_getattr, 5795 .inode_setxattr = selinux_inode_setxattr, 5796 .inode_post_setxattr = selinux_inode_post_setxattr, 5797 .inode_getxattr = selinux_inode_getxattr, 5798 .inode_listxattr = selinux_inode_listxattr, 5799 .inode_removexattr = selinux_inode_removexattr, 5800 .inode_getsecurity = selinux_inode_getsecurity, 5801 .inode_setsecurity = selinux_inode_setsecurity, 5802 .inode_listsecurity = selinux_inode_listsecurity, 5803 .inode_getsecid = selinux_inode_getsecid, 5804 5805 .file_permission = selinux_file_permission, 5806 .file_alloc_security = selinux_file_alloc_security, 5807 .file_free_security = selinux_file_free_security, 5808 .file_ioctl = selinux_file_ioctl, 5809 .mmap_file = selinux_mmap_file, 5810 .mmap_addr = selinux_mmap_addr, 5811 .file_mprotect = selinux_file_mprotect, 5812 .file_lock = selinux_file_lock, 5813 .file_fcntl = selinux_file_fcntl, 5814 .file_set_fowner = selinux_file_set_fowner, 5815 .file_send_sigiotask = selinux_file_send_sigiotask, 5816 .file_receive = selinux_file_receive, 5817 5818 .file_open = selinux_file_open, 5819 5820 .task_create = selinux_task_create, 5821 .cred_alloc_blank = selinux_cred_alloc_blank, 5822 .cred_free = selinux_cred_free, 5823 .cred_prepare = selinux_cred_prepare, 5824 .cred_transfer = selinux_cred_transfer, 5825 .kernel_act_as = selinux_kernel_act_as, 5826 .kernel_create_files_as = selinux_kernel_create_files_as, 5827 .kernel_module_request = selinux_kernel_module_request, 5828 .task_setpgid = selinux_task_setpgid, 5829 .task_getpgid = selinux_task_getpgid, 5830 .task_getsid = selinux_task_getsid, 5831 .task_getsecid = selinux_task_getsecid, 5832 .task_setnice = selinux_task_setnice, 5833 .task_setioprio = selinux_task_setioprio, 5834 .task_getioprio = selinux_task_getioprio, 5835 .task_setrlimit = selinux_task_setrlimit, 5836 .task_setscheduler = selinux_task_setscheduler, 5837 .task_getscheduler = selinux_task_getscheduler, 5838 .task_movememory = selinux_task_movememory, 5839 .task_kill = selinux_task_kill, 5840 .task_wait = selinux_task_wait, 5841 .task_to_inode = selinux_task_to_inode, 5842 5843 .ipc_permission = selinux_ipc_permission, 5844 .ipc_getsecid = selinux_ipc_getsecid, 5845 5846 .msg_msg_alloc_security = selinux_msg_msg_alloc_security, 5847 .msg_msg_free_security = selinux_msg_msg_free_security, 5848 5849 .msg_queue_alloc_security = selinux_msg_queue_alloc_security, 5850 .msg_queue_free_security = selinux_msg_queue_free_security, 5851 .msg_queue_associate = selinux_msg_queue_associate, 5852 .msg_queue_msgctl = selinux_msg_queue_msgctl, 5853 .msg_queue_msgsnd = selinux_msg_queue_msgsnd, 5854 .msg_queue_msgrcv = selinux_msg_queue_msgrcv, 5855 5856 .shm_alloc_security = selinux_shm_alloc_security, 5857 .shm_free_security = selinux_shm_free_security, 5858 .shm_associate = selinux_shm_associate, 5859 .shm_shmctl = selinux_shm_shmctl, 5860 .shm_shmat = selinux_shm_shmat, 5861 5862 .sem_alloc_security = selinux_sem_alloc_security, 5863 .sem_free_security = selinux_sem_free_security, 5864 .sem_associate = selinux_sem_associate, 5865 .sem_semctl = selinux_sem_semctl, 5866 .sem_semop = selinux_sem_semop, 5867 5868 .d_instantiate = selinux_d_instantiate, 5869 5870 .getprocattr = selinux_getprocattr, 5871 .setprocattr = selinux_setprocattr, 5872 5873 .ismaclabel = selinux_ismaclabel, 5874 .secid_to_secctx = selinux_secid_to_secctx, 5875 .secctx_to_secid = selinux_secctx_to_secid, 5876 .release_secctx = selinux_release_secctx, 5877 .inode_notifysecctx = selinux_inode_notifysecctx, 5878 .inode_setsecctx = selinux_inode_setsecctx, 5879 .inode_getsecctx = selinux_inode_getsecctx, 5880 5881 .unix_stream_connect = selinux_socket_unix_stream_connect, 5882 .unix_may_send = selinux_socket_unix_may_send, 5883 5884 .socket_create = selinux_socket_create, 5885 .socket_post_create = selinux_socket_post_create, 5886 .socket_bind = selinux_socket_bind, 5887 .socket_connect = selinux_socket_connect, 5888 .socket_listen = selinux_socket_listen, 5889 .socket_accept = selinux_socket_accept, 5890 .socket_sendmsg = selinux_socket_sendmsg, 5891 .socket_recvmsg = selinux_socket_recvmsg, 5892 .socket_getsockname = selinux_socket_getsockname, 5893 .socket_getpeername = selinux_socket_getpeername, 5894 .socket_getsockopt = selinux_socket_getsockopt, 5895 .socket_setsockopt = selinux_socket_setsockopt, 5896 .socket_shutdown = selinux_socket_shutdown, 5897 .socket_sock_rcv_skb = selinux_socket_sock_rcv_skb, 5898 .socket_getpeersec_stream = selinux_socket_getpeersec_stream, 5899 .socket_getpeersec_dgram = selinux_socket_getpeersec_dgram, 5900 .sk_alloc_security = selinux_sk_alloc_security, 5901 .sk_free_security = selinux_sk_free_security, 5902 .sk_clone_security = selinux_sk_clone_security, 5903 .sk_getsecid = selinux_sk_getsecid, 5904 .sock_graft = selinux_sock_graft, 5905 .inet_conn_request = selinux_inet_conn_request, 5906 .inet_csk_clone = selinux_inet_csk_clone, 5907 .inet_conn_established = selinux_inet_conn_established, 5908 .secmark_relabel_packet = selinux_secmark_relabel_packet, 5909 .secmark_refcount_inc = selinux_secmark_refcount_inc, 5910 .secmark_refcount_dec = selinux_secmark_refcount_dec, 5911 .req_classify_flow = selinux_req_classify_flow, 5912 .tun_dev_alloc_security = selinux_tun_dev_alloc_security, 5913 .tun_dev_free_security = selinux_tun_dev_free_security, 5914 .tun_dev_create = selinux_tun_dev_create, 5915 .tun_dev_attach_queue = selinux_tun_dev_attach_queue, 5916 .tun_dev_attach = selinux_tun_dev_attach, 5917 .tun_dev_open = selinux_tun_dev_open, 5918 .skb_owned_by = selinux_skb_owned_by, 5919 5920#ifdef CONFIG_SECURITY_NETWORK_XFRM 5921 .xfrm_policy_alloc_security = selinux_xfrm_policy_alloc, 5922 .xfrm_policy_clone_security = selinux_xfrm_policy_clone, 5923 .xfrm_policy_free_security = selinux_xfrm_policy_free, 5924 .xfrm_policy_delete_security = selinux_xfrm_policy_delete, 5925 .xfrm_state_alloc = selinux_xfrm_state_alloc, 5926 .xfrm_state_alloc_acquire = selinux_xfrm_state_alloc_acquire, 5927 .xfrm_state_free_security = selinux_xfrm_state_free, 5928 .xfrm_state_delete_security = selinux_xfrm_state_delete, 5929 .xfrm_policy_lookup = selinux_xfrm_policy_lookup, 5930 .xfrm_state_pol_flow_match = selinux_xfrm_state_pol_flow_match, 5931 .xfrm_decode_session = selinux_xfrm_decode_session, 5932#endif 5933 5934#ifdef CONFIG_KEYS 5935 .key_alloc = selinux_key_alloc, 5936 .key_free = selinux_key_free, 5937 .key_permission = selinux_key_permission, 5938 .key_getsecurity = selinux_key_getsecurity, 5939#endif 5940 5941#ifdef CONFIG_AUDIT 5942 .audit_rule_init = selinux_audit_rule_init, 5943 .audit_rule_known = selinux_audit_rule_known, 5944 .audit_rule_match = selinux_audit_rule_match, 5945 .audit_rule_free = selinux_audit_rule_free, 5946#endif 5947}; 5948 5949static __init int selinux_init(void) 5950{ 5951 if (!security_module_enable(&selinux_ops)) { 5952 selinux_enabled = 0; 5953 return 0; 5954 } 5955 5956 if (!selinux_enabled) { 5957 printk(KERN_INFO "SELinux: Disabled at boot.\n"); 5958 return 0; 5959 } 5960 5961 printk(KERN_INFO "SELinux: Initializing.\n"); 5962 5963 /* Set the security state for the initial task. */ 5964 cred_init_security(); 5965 5966 default_noexec = !(VM_DATA_DEFAULT_FLAGS & VM_EXEC); 5967 5968 sel_inode_cache = kmem_cache_create("selinux_inode_security", 5969 sizeof(struct inode_security_struct), 5970 0, SLAB_PANIC, NULL); 5971 avc_init(); 5972 5973 if (register_security(&selinux_ops)) 5974 panic("SELinux: Unable to register with kernel.\n"); 5975 5976 if (selinux_enforcing) 5977 printk(KERN_DEBUG "SELinux: Starting in enforcing mode\n"); 5978 else 5979 printk(KERN_DEBUG "SELinux: Starting in permissive mode\n"); 5980 5981 return 0; 5982} 5983 5984static void delayed_superblock_init(struct super_block *sb, void *unused) 5985{ 5986 superblock_doinit(sb, NULL); 5987} 5988 5989void selinux_complete_init(void) 5990{ 5991 printk(KERN_DEBUG "SELinux: Completing initialization.\n"); 5992 5993 /* Set up any superblocks initialized prior to the policy load. */ 5994 printk(KERN_DEBUG "SELinux: Setting up existing superblocks.\n"); 5995 iterate_supers(delayed_superblock_init, NULL); 5996} 5997 5998/* SELinux requires early initialization in order to label 5999 all processes and objects when they are created. */ 6000security_initcall(selinux_init); 6001 6002#if defined(CONFIG_NETFILTER) 6003 6004static struct nf_hook_ops selinux_ipv4_ops[] = { 6005 { 6006 .hook = selinux_ipv4_postroute, 6007 .owner = THIS_MODULE, 6008 .pf = NFPROTO_IPV4, 6009 .hooknum = NF_INET_POST_ROUTING, 6010 .priority = NF_IP_PRI_SELINUX_LAST, 6011 }, 6012 { 6013 .hook = selinux_ipv4_forward, 6014 .owner = THIS_MODULE, 6015 .pf = NFPROTO_IPV4, 6016 .hooknum = NF_INET_FORWARD, 6017 .priority = NF_IP_PRI_SELINUX_FIRST, 6018 }, 6019 { 6020 .hook = selinux_ipv4_output, 6021 .owner = THIS_MODULE, 6022 .pf = NFPROTO_IPV4, 6023 .hooknum = NF_INET_LOCAL_OUT, 6024 .priority = NF_IP_PRI_SELINUX_FIRST, 6025 } 6026}; 6027 6028#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE) 6029 6030static struct nf_hook_ops selinux_ipv6_ops[] = { 6031 { 6032 .hook = selinux_ipv6_postroute, 6033 .owner = THIS_MODULE, 6034 .pf = NFPROTO_IPV6, 6035 .hooknum = NF_INET_POST_ROUTING, 6036 .priority = NF_IP6_PRI_SELINUX_LAST, 6037 }, 6038 { 6039 .hook = selinux_ipv6_forward, 6040 .owner = THIS_MODULE, 6041 .pf = NFPROTO_IPV6, 6042 .hooknum = NF_INET_FORWARD, 6043 .priority = NF_IP6_PRI_SELINUX_FIRST, 6044 } 6045}; 6046 6047#endif /* IPV6 */ 6048 6049static int __init selinux_nf_ip_init(void) 6050{ 6051 int err = 0; 6052 6053 if (!selinux_enabled) 6054 goto out; 6055 6056 printk(KERN_DEBUG "SELinux: Registering netfilter hooks\n"); 6057 6058 err = nf_register_hooks(selinux_ipv4_ops, ARRAY_SIZE(selinux_ipv4_ops)); 6059 if (err) 6060 panic("SELinux: nf_register_hooks for IPv4: error %d\n", err); 6061 6062#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE) 6063 err = nf_register_hooks(selinux_ipv6_ops, ARRAY_SIZE(selinux_ipv6_ops)); 6064 if (err) 6065 panic("SELinux: nf_register_hooks for IPv6: error %d\n", err); 6066#endif /* IPV6 */ 6067 6068out: 6069 return err; 6070} 6071 6072__initcall(selinux_nf_ip_init); 6073 6074#ifdef CONFIG_SECURITY_SELINUX_DISABLE 6075static void selinux_nf_ip_exit(void) 6076{ 6077 printk(KERN_DEBUG "SELinux: Unregistering netfilter hooks\n"); 6078 6079 nf_unregister_hooks(selinux_ipv4_ops, ARRAY_SIZE(selinux_ipv4_ops)); 6080#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE) 6081 nf_unregister_hooks(selinux_ipv6_ops, ARRAY_SIZE(selinux_ipv6_ops)); 6082#endif /* IPV6 */ 6083} 6084#endif 6085 6086#else /* CONFIG_NETFILTER */ 6087 6088#ifdef CONFIG_SECURITY_SELINUX_DISABLE 6089#define selinux_nf_ip_exit() 6090#endif 6091 6092#endif /* CONFIG_NETFILTER */ 6093 6094#ifdef CONFIG_SECURITY_SELINUX_DISABLE 6095static int selinux_disabled; 6096 6097int selinux_disable(void) 6098{ 6099 if (ss_initialized) { 6100 /* Not permitted after initial policy load. */ 6101 return -EINVAL; 6102 } 6103 6104 if (selinux_disabled) { 6105 /* Only do this once. */ 6106 return -EINVAL; 6107 } 6108 6109 printk(KERN_INFO "SELinux: Disabled at runtime.\n"); 6110 6111 selinux_disabled = 1; 6112 selinux_enabled = 0; 6113 6114 reset_security_ops(); 6115 6116 /* Try to destroy the avc node cache */ 6117 avc_disable(); 6118 6119 /* Unregister netfilter hooks. */ 6120 selinux_nf_ip_exit(); 6121 6122 /* Unregister selinuxfs. */ 6123 exit_sel_fs(); 6124 6125 return 0; 6126} 6127#endif