security/selinux/hooks.c

   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 Hewlett-Packard Development Company, L.P.
  17  *              Paul Moore <paul.moore@hp.com>
  18  *  Copyright (C) 2007 Hitachi Software Engineering Co., Ltd.
  19  *                     Yuichi Nakamura <ynakam@hitachisoft.jp>
  20  *
  21  *      This program is free software; you can redistribute it and/or modify
  22  *      it under the terms of the GNU General Public License version 2,
  23  *      as published by the Free Software Foundation.
  24  */
  25
  26 #include <linux/init.h>
  27 #include <linux/kernel.h>
  28 #include <linux/tracehook.h>
  29 #include <linux/errno.h>
  30 #include <linux/sched.h>
  31 #include <linux/security.h>
  32 #include <linux/xattr.h>
  33 #include <linux/capability.h>
  34 #include <linux/unistd.h>
  35 #include <linux/mm.h>
  36 #include <linux/mman.h>
  37 #include <linux/slab.h>
  38 #include <linux/pagemap.h>
  39 #include <linux/swap.h>
  40 #include <linux/spinlock.h>
  41 #include <linux/syscalls.h>
  42 #include <linux/file.h>
  43 #include <linux/fdtable.h>
  44 #include <linux/namei.h>
  45 #include <linux/mount.h>
  46 #include <linux/proc_fs.h>
  47 #include <linux/netfilter_ipv4.h>
  48 #include <linux/netfilter_ipv6.h>
  49 #include <linux/tty.h>
  50 #include <net/icmp.h>
  51 #include <net/ip.h>             /* for local_port_range[] */
  52 #include <net/tcp.h>            /* struct or_callable used in sock_rcv_skb */
  53 #include <net/net_namespace.h>
  54 #include <net/netlabel.h>
  55 #include <linux/uaccess.h>
  56 #include <asm/ioctls.h>
  57 #include <asm/atomic.h>
  58 #include <linux/bitops.h>
  59 #include <linux/interrupt.h>
  60 #include <linux/netdevice.h>    /* for network interface checks */
  61 #include <linux/netlink.h>
  62 #include <linux/tcp.h>
  63 #include <linux/udp.h>
  64 #include <linux/dccp.h>
  65 #include <linux/quota.h>
  66 #include <linux/un.h>           /* for Unix socket types */
  67 #include <net/af_unix.h>        /* for Unix socket types */
  68 #include <linux/parser.h>
  69 #include <linux/nfs_mount.h>
  70 #include <net/ipv6.h>
  71 #include <linux/hugetlb.h>
  72 #include <linux/personality.h>
  73 #include <linux/sysctl.h>
  74 #include <linux/audit.h>
  75 #include <linux/string.h>
  76 #include <linux/selinux.h>
  77 #include <linux/mutex.h>
  78
  79 #include "avc.h"
  80 #include "objsec.h"
  81 #include "netif.h"
  82 #include "netnode.h"
  83 #include "netport.h"
  84 #include "xfrm.h"
  85 #include "netlabel.h"
  86 #include "audit.h"
  87
  88 #define XATTR_SELINUX_SUFFIX "selinux"
  89 #define XATTR_NAME_SELINUX XATTR_SECURITY_PREFIX XATTR_SELINUX_SUFFIX
  90
  91 #define NUM_SEL_MNT_OPTS 4
  92
  93 extern unsigned int policydb_loaded_version;
  94 extern int selinux_nlmsg_lookup(u16 sclass, u16 nlmsg_type, u32 *perm);
  95 extern int selinux_compat_net;
  96 extern struct security_operations *security_ops;
  97
  98 /* SECMARK reference count */
  99 atomic_t selinux_secmark_refcount = ATOMIC_INIT(0);
 100
 101 #ifdef CONFIG_SECURITY_SELINUX_DEVELOP
 102 int selinux_enforcing;
 103
 104 static int __init enforcing_setup(char *str)
 105 {
 106         unsigned long enforcing;
 107         if (!strict_strtoul(str, 0, &enforcing))
 108                 selinux_enforcing = enforcing ? 1 : 0;
 109         return 1;
 110 }
 111 __setup("enforcing=", enforcing_setup);
 112 #endif
 113
 114 #ifdef CONFIG_SECURITY_SELINUX_BOOTPARAM
 115 int selinux_enabled = CONFIG_SECURITY_SELINUX_BOOTPARAM_VALUE;
 116
 117 static int __init selinux_enabled_setup(char *str)
 118 {
 119         unsigned long enabled;
 120         if (!strict_strtoul(str, 0, &enabled))
 121                 selinux_enabled = enabled ? 1 : 0;
 122         return 1;
 123 }
 124 __setup("selinux=", selinux_enabled_setup);
 125 #else
 126 int selinux_enabled = 1;
 127 #endif
 128
 129
 130 /*
 131  * Minimal support for a secondary security module,
 132  * just to allow the use of the capability module.
 133  */
 134 static struct security_operations *secondary_ops;
 135
 136 /* Lists of inode and superblock security structures initialized
 137    before the policy was loaded. */
 138 static LIST_HEAD(superblock_security_head);
 139 static DEFINE_SPINLOCK(sb_security_lock);
 140
 141 static struct kmem_cache *sel_inode_cache;
 142
 143 /**
 144  * selinux_secmark_enabled - Check to see if SECMARK is currently enabled
 145  *
 146  * Description:
 147  * This function checks the SECMARK reference counter to see if any SECMARK
 148  * targets are currently configured, if the reference counter is greater than
 149  * zero SECMARK is considered to be enabled.  Returns true (1) if SECMARK is
 150  * enabled, false (0) if SECMARK is disabled.
 151  *
 152  */
 153 static int selinux_secmark_enabled(void)
 154 {
 155         return (atomic_read(&selinux_secmark_refcount) > 0);
 156 }
 157
 158 /* Allocate and free functions for each kind of security blob. */
 159
 160 static int task_alloc_security(struct task_struct *task)
 161 {
 162         struct task_security_struct *tsec;
 163
 164         tsec = kzalloc(sizeof(struct task_security_struct), GFP_KERNEL);
 165         if (!tsec)
 166                 return -ENOMEM;
 167
 168         tsec->osid = tsec->sid = SECINITSID_UNLABELED;
 169         task->security = tsec;
 170
 171         return 0;
 172 }
 173
 174 static void task_free_security(struct task_struct *task)
 175 {
 176         struct task_security_struct *tsec = task->security;
 177         task->security = NULL;
 178         kfree(tsec);
 179 }
 180
 181 static int inode_alloc_security(struct inode *inode)
 182 {
 183         struct task_security_struct *tsec = current->security;
 184         struct inode_security_struct *isec;
 185
 186         isec = kmem_cache_zalloc(sel_inode_cache, GFP_NOFS);
 187         if (!isec)
 188                 return -ENOMEM;
 189
 190         mutex_init(&isec->lock);
 191         INIT_LIST_HEAD(&isec->list);
 192         isec->inode = inode;
 193         isec->sid = SECINITSID_UNLABELED;
 194         isec->sclass = SECCLASS_FILE;
 195         isec->task_sid = tsec->sid;
 196         inode->i_security = isec;
 197
 198         return 0;
 199 }
 200
 201 static void inode_free_security(struct inode *inode)
 202 {
 203         struct inode_security_struct *isec = inode->i_security;
 204         struct superblock_security_struct *sbsec = inode->i_sb->s_security;
 205
 206         spin_lock(&sbsec->isec_lock);
 207         if (!list_empty(&isec->list))
 208                 list_del_init(&isec->list);
 209         spin_unlock(&sbsec->isec_lock);
 210
 211         inode->i_security = NULL;
 212         kmem_cache_free(sel_inode_cache, isec);
 213 }
 214
 215 static int file_alloc_security(struct file *file)
 216 {
 217         struct task_security_struct *tsec = current->security;
 218         struct file_security_struct *fsec;
 219
 220         fsec = kzalloc(sizeof(struct file_security_struct), GFP_KERNEL);
 221         if (!fsec)
 222                 return -ENOMEM;
 223
 224         fsec->sid = tsec->sid;
 225         fsec->fown_sid = tsec->sid;
 226         file->f_security = fsec;
 227
 228         return 0;
 229 }
 230
 231 static void file_free_security(struct file *file)
 232 {
 233         struct file_security_struct *fsec = file->f_security;
 234         file->f_security = NULL;
 235         kfree(fsec);
 236 }
 237
 238 static int superblock_alloc_security(struct super_block *sb)
 239 {
 240         struct superblock_security_struct *sbsec;
 241
 242         sbsec = kzalloc(sizeof(struct superblock_security_struct), GFP_KERNEL);
 243         if (!sbsec)
 244                 return -ENOMEM;
 245
 246         mutex_init(&sbsec->lock);
 247         INIT_LIST_HEAD(&sbsec->list);
 248         INIT_LIST_HEAD(&sbsec->isec_head);
 249         spin_lock_init(&sbsec->isec_lock);
 250         sbsec->sb = sb;
 251         sbsec->sid = SECINITSID_UNLABELED;
 252         sbsec->def_sid = SECINITSID_FILE;
 253         sbsec->mntpoint_sid = SECINITSID_UNLABELED;
 254         sb->s_security = sbsec;
 255
 256         return 0;
 257 }
 258
 259 static void superblock_free_security(struct super_block *sb)
 260 {
 261         struct superblock_security_struct *sbsec = sb->s_security;
 262
 263         spin_lock(&sb_security_lock);
 264         if (!list_empty(&sbsec->list))
 265                 list_del_init(&sbsec->list);
 266         spin_unlock(&sb_security_lock);
 267
 268         sb->s_security = NULL;
 269         kfree(sbsec);
 270 }
 271
 272 static int sk_alloc_security(struct sock *sk, int family, gfp_t priority)
 273 {
 274         struct sk_security_struct *ssec;
 275
 276         ssec = kzalloc(sizeof(*ssec), priority);
 277         if (!ssec)
 278                 return -ENOMEM;
 279
 280         ssec->peer_sid = SECINITSID_UNLABELED;
 281         ssec->sid = SECINITSID_UNLABELED;
 282         sk->sk_security = ssec;
 283
 284         selinux_netlbl_sk_security_reset(ssec, family);
 285
 286         return 0;
 287 }
 288
 289 static void sk_free_security(struct sock *sk)
 290 {
 291         struct sk_security_struct *ssec = sk->sk_security;
 292
 293         sk->sk_security = NULL;
 294         kfree(ssec);
 295 }
 296
 297 /* The security server must be initialized before
 298    any labeling or access decisions can be provided. */
 299 extern int ss_initialized;
 300
 301 /* The file system's label must be initialized prior to use. */
 302
 303 static char *labeling_behaviors[6] = {
 304         "uses xattr",
 305         "uses transition SIDs",
 306         "uses task SIDs",
 307         "uses genfs_contexts",
 308         "not configured for labeling",
 309         "uses mountpoint labeling",
 310 };
 311
 312 static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dentry);
 313
 314 static inline int inode_doinit(struct inode *inode)
 315 {
 316         return inode_doinit_with_dentry(inode, NULL);
 317 }
 318
 319 enum {
 320         Opt_error = -1,
 321         Opt_context = 1,
 322         Opt_fscontext = 2,
 323         Opt_defcontext = 3,
 324         Opt_rootcontext = 4,
 325 };
 326
 327 static match_table_t tokens = {
 328         {Opt_context, CONTEXT_STR "%s"},
 329         {Opt_fscontext, FSCONTEXT_STR "%s"},
 330         {Opt_defcontext, DEFCONTEXT_STR "%s"},
 331         {Opt_rootcontext, ROOTCONTEXT_STR "%s"},
 332         {Opt_error, NULL},
 333 };
 334
 335 #define SEL_MOUNT_FAIL_MSG "SELinux:  duplicate or incompatible mount options\n"
 336
 337 static int may_context_mount_sb_relabel(u32 sid,
 338                         struct superblock_security_struct *sbsec,
 339                         struct task_security_struct *tsec)
 340 {
 341         int rc;
 342
 343         rc = avc_has_perm(tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM,
 344                           FILESYSTEM__RELABELFROM, NULL);
 345         if (rc)
 346                 return rc;
 347
 348         rc = avc_has_perm(tsec->sid, sid, SECCLASS_FILESYSTEM,
 349                           FILESYSTEM__RELABELTO, NULL);
 350         return rc;
 351 }
 352
 353 static int may_context_mount_inode_relabel(u32 sid,
 354                         struct superblock_security_struct *sbsec,
 355                         struct task_security_struct *tsec)
 356 {
 357         int rc;
 358         rc = avc_has_perm(tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM,
 359                           FILESYSTEM__RELABELFROM, NULL);
 360         if (rc)
 361                 return rc;
 362
 363         rc = avc_has_perm(sid, sbsec->sid, SECCLASS_FILESYSTEM,
 364                           FILESYSTEM__ASSOCIATE, NULL);
 365         return rc;
 366 }
 367
 368 static int sb_finish_set_opts(struct super_block *sb)
 369 {
 370         struct superblock_security_struct *sbsec = sb->s_security;
 371         struct dentry *root = sb->s_root;
 372         struct inode *root_inode = root->d_inode;
 373         int rc = 0;
 374
 375         if (sbsec->behavior == SECURITY_FS_USE_XATTR) {
 376                 /* Make sure that the xattr handler exists and that no
 377                    error other than -ENODATA is returned by getxattr on
 378                    the root directory.  -ENODATA is ok, as this may be
 379                    the first boot of the SELinux kernel before we have
 380                    assigned xattr values to the filesystem. */
 381                 if (!root_inode->i_op->getxattr) {
 382                         printk(KERN_WARNING "SELinux: (dev %s, type %s) has no "
 383                                "xattr support\n", sb->s_id, sb->s_type->name);
 384                         rc = -EOPNOTSUPP;
 385                         goto out;
 386                 }
 387                 rc = root_inode->i_op->getxattr(root, XATTR_NAME_SELINUX, NULL, 0);
 388                 if (rc < 0 && rc != -ENODATA) {
 389                         if (rc == -EOPNOTSUPP)
 390                                 printk(KERN_WARNING "SELinux: (dev %s, type "
 391                                        "%s) has no security xattr handler\n",
 392                                        sb->s_id, sb->s_type->name);
 393                         else
 394                                 printk(KERN_WARNING "SELinux: (dev %s, type "
 395                                        "%s) getxattr errno %d\n", sb->s_id,
 396                                        sb->s_type->name, -rc);
 397                         goto out;
 398                 }
 399         }
 400
 401         sbsec->initialized = 1;
 402
 403         if (sbsec->behavior > ARRAY_SIZE(labeling_behaviors))
 404                 printk(KERN_ERR "SELinux: initialized (dev %s, type %s), unknown behavior\n",
 405                        sb->s_id, sb->s_type->name);
 406         else
 407                 printk(KERN_DEBUG "SELinux: initialized (dev %s, type %s), %s\n",
 408                        sb->s_id, sb->s_type->name,
 409                        labeling_behaviors[sbsec->behavior-1]);
 410
 411         /* Initialize the root inode. */
 412         rc = inode_doinit_with_dentry(root_inode, root);
 413
 414         /* Initialize any other inodes associated with the superblock, e.g.
 415            inodes created prior to initial policy load or inodes created
 416            during get_sb by a pseudo filesystem that directly
 417            populates itself. */
 418         spin_lock(&sbsec->isec_lock);
 419 next_inode:
 420         if (!list_empty(&sbsec->isec_head)) {
 421                 struct inode_security_struct *isec =
 422                                 list_entry(sbsec->isec_head.next,
 423                                            struct inode_security_struct, list);
 424                 struct inode *inode = isec->inode;
 425                 spin_unlock(&sbsec->isec_lock);
 426                 inode = igrab(inode);
 427                 if (inode) {
 428                         if (!IS_PRIVATE(inode))
 429                                 inode_doinit(inode);
 430                         iput(inode);
 431                 }
 432                 spin_lock(&sbsec->isec_lock);
 433                 list_del_init(&isec->list);
 434                 goto next_inode;
 435         }
 436         spin_unlock(&sbsec->isec_lock);
 437 out:
 438         return rc;
 439 }
 440
 441 /*
 442  * This function should allow an FS to ask what it's mount security
 443  * options were so it can use those later for submounts, displaying
 444  * mount options, or whatever.
 445  */
 446 static int selinux_get_mnt_opts(const struct super_block *sb,
 447                                 struct security_mnt_opts *opts)
 448 {
 449         int rc = 0, i;
 450         struct superblock_security_struct *sbsec = sb->s_security;
 451         char *context = NULL;
 452         u32 len;
 453         char tmp;
 454
 455         security_init_mnt_opts(opts);
 456
 457         if (!sbsec->initialized)
 458                 return -EINVAL;
 459
 460         if (!ss_initialized)
 461                 return -EINVAL;
 462
 463         /*
 464          * if we ever use sbsec flags for anything other than tracking mount
 465          * settings this is going to need a mask
 466          */
 467         tmp = sbsec->flags;
 468         /* count the number of mount options for this sb */
 469         for (i = 0; i < 8; i++) {
 470                 if (tmp & 0x01)
 471                         opts->num_mnt_opts++;
 472                 tmp >>= 1;
 473         }
 474
 475         opts->mnt_opts = kcalloc(opts->num_mnt_opts, sizeof(char *), GFP_ATOMIC);
 476         if (!opts->mnt_opts) {
 477                 rc = -ENOMEM;
 478                 goto out_free;
 479         }
 480
 481         opts->mnt_opts_flags = kcalloc(opts->num_mnt_opts, sizeof(int), GFP_ATOMIC);
 482         if (!opts->mnt_opts_flags) {
 483                 rc = -ENOMEM;
 484                 goto out_free;
 485         }
 486
 487         i = 0;
 488         if (sbsec->flags & FSCONTEXT_MNT) {
 489                 rc = security_sid_to_context(sbsec->sid, &context, &len);
 490                 if (rc)
 491                         goto out_free;
 492                 opts->mnt_opts[i] = context;
 493                 opts->mnt_opts_flags[i++] = FSCONTEXT_MNT;
 494         }
 495         if (sbsec->flags & CONTEXT_MNT) {
 496                 rc = security_sid_to_context(sbsec->mntpoint_sid, &context, &len);
 497                 if (rc)
 498                         goto out_free;
 499                 opts->mnt_opts[i] = context;
 500                 opts->mnt_opts_flags[i++] = CONTEXT_MNT;
 501         }
 502         if (sbsec->flags & DEFCONTEXT_MNT) {
 503                 rc = security_sid_to_context(sbsec->def_sid, &context, &len);
 504                 if (rc)
 505                         goto out_free;
 506                 opts->mnt_opts[i] = context;
 507                 opts->mnt_opts_flags[i++] = DEFCONTEXT_MNT;
 508         }
 509         if (sbsec->flags & ROOTCONTEXT_MNT) {
 510                 struct inode *root = sbsec->sb->s_root->d_inode;
 511                 struct inode_security_struct *isec = root->i_security;
 512
 513                 rc = security_sid_to_context(isec->sid, &context, &len);
 514                 if (rc)
 515                         goto out_free;
 516                 opts->mnt_opts[i] = context;
 517                 opts->mnt_opts_flags[i++] = ROOTCONTEXT_MNT;
 518         }
 519
 520         BUG_ON(i != opts->num_mnt_opts);
 521
 522         return 0;
 523
 524 out_free:
 525         security_free_mnt_opts(opts);
 526         return rc;
 527 }
 528
 529 static int bad_option(struct superblock_security_struct *sbsec, char flag,
 530                       u32 old_sid, u32 new_sid)
 531 {
 532         /* check if the old mount command had the same options */
 533         if (sbsec->initialized)
 534                 if (!(sbsec->flags & flag) ||
 535                     (old_sid != new_sid))
 536                         return 1;
 537
 538         /* check if we were passed the same options twice,
 539          * aka someone passed context=a,context=b
 540          */
 541         if (!sbsec->initialized)
 542                 if (sbsec->flags & flag)
 543                         return 1;
 544         return 0;
 545 }
 546
 547 /*
 548  * Allow filesystems with binary mount data to explicitly set mount point
 549  * labeling information.
 550  */
 551 static int selinux_set_mnt_opts(struct super_block *sb,
 552                                 struct security_mnt_opts *opts)
 553 {
 554         int rc = 0, i;
 555         struct task_security_struct *tsec = current->security;
 556         struct superblock_security_struct *sbsec = sb->s_security;
 557         const char *name = sb->s_type->name;
 558         struct inode *inode = sbsec->sb->s_root->d_inode;
 559         struct inode_security_struct *root_isec = inode->i_security;
 560         u32 fscontext_sid = 0, context_sid = 0, rootcontext_sid = 0;
 561         u32 defcontext_sid = 0;
 562         char **mount_options = opts->mnt_opts;
 563         int *flags = opts->mnt_opts_flags;
 564         int num_opts = opts->num_mnt_opts;
 565
 566         mutex_lock(&sbsec->lock);
 567
 568         if (!ss_initialized) {
 569                 if (!num_opts) {
 570                         /* Defer initialization until selinux_complete_init,
 571                            after the initial policy is loaded and the security
 572                            server is ready to handle calls. */
 573                         spin_lock(&sb_security_lock);
 574                         if (list_empty(&sbsec->list))
 575                                 list_add(&sbsec->list, &superblock_security_head);
 576                         spin_unlock(&sb_security_lock);
 577                         goto out;
 578                 }
 579                 rc = -EINVAL;
 580                 printk(KERN_WARNING "SELinux: Unable to set superblock options "
 581                         "before the security server is initialized\n");
 582                 goto out;
 583         }
 584
 585         /*
 586          * Binary mount data FS will come through this function twice.  Once
 587          * from an explicit call and once from the generic calls from the vfs.
 588          * Since the generic VFS calls will not contain any security mount data
 589          * we need to skip the double mount verification.
 590          *
 591          * This does open a hole in which we will not notice if the first
 592          * mount using this sb set explict options and a second mount using
 593          * this sb does not set any security options.  (The first options
 594          * will be used for both mounts)
 595          */
 596         if (sbsec->initialized && (sb->s_type->fs_flags & FS_BINARY_MOUNTDATA)
 597             && (num_opts == 0))
 598                 goto out;
 599
 600         /*
 601          * parse the mount options, check if they are valid sids.
 602          * also check if someone is trying to mount the same sb more
 603          * than once with different security options.
 604          */
 605         for (i = 0; i < num_opts; i++) {
 606                 u32 sid;
 607                 rc = security_context_to_sid(mount_options[i],
 608                                              strlen(mount_options[i]), &sid);
 609                 if (rc) {
 610                         printk(KERN_WARNING "SELinux: security_context_to_sid"
 611                                "(%s) failed for (dev %s, type %s) errno=%d\n",
 612                                mount_options[i], sb->s_id, name, rc);
 613                         goto out;
 614                 }
 615                 switch (flags[i]) {
 616                 case FSCONTEXT_MNT:
 617                         fscontext_sid = sid;
 618
 619                         if (bad_option(sbsec, FSCONTEXT_MNT, sbsec->sid,
 620                                         fscontext_sid))
 621                                 goto out_double_mount;
 622
 623                         sbsec->flags |= FSCONTEXT_MNT;
 624                         break;
 625                 case CONTEXT_MNT:
 626                         context_sid = sid;
 627
 628                         if (bad_option(sbsec, CONTEXT_MNT, sbsec->mntpoint_sid,
 629                                         context_sid))
 630                                 goto out_double_mount;
 631
 632                         sbsec->flags |= CONTEXT_MNT;
 633                         break;
 634                 case ROOTCONTEXT_MNT:
 635                         rootcontext_sid = sid;
 636
 637                         if (bad_option(sbsec, ROOTCONTEXT_MNT, root_isec->sid,
 638                                         rootcontext_sid))
 639                                 goto out_double_mount;
 640
 641                         sbsec->flags |= ROOTCONTEXT_MNT;
 642
 643                         break;
 644                 case DEFCONTEXT_MNT:
 645                         defcontext_sid = sid;
 646
 647                         if (bad_option(sbsec, DEFCONTEXT_MNT, sbsec->def_sid,
 648                                         defcontext_sid))
 649                                 goto out_double_mount;
 650
 651                         sbsec->flags |= DEFCONTEXT_MNT;
 652
 653                         break;
 654                 default:
 655                         rc = -EINVAL;
 656                         goto out;
 657                 }
 658         }
 659
 660         if (sbsec->initialized) {
 661                 /* previously mounted with options, but not on this attempt? */
 662                 if (sbsec->flags && !num_opts)
 663                         goto out_double_mount;
 664                 rc = 0;
 665                 goto out;
 666         }
 667
 668         if (strcmp(sb->s_type->name, "proc") == 0)
 669                 sbsec->proc = 1;
 670
 671         /* Determine the labeling behavior to use for this filesystem type. */
 672         rc = security_fs_use(sb->s_type->name, &sbsec->behavior, &sbsec->sid);
 673         if (rc) {
 674                 printk(KERN_WARNING "%s: security_fs_use(%s) returned %d\n",
 675                        __func__, sb->s_type->name, rc);
 676                 goto out;
 677         }
 678
 679         /* sets the context of the superblock for the fs being mounted. */
 680         if (fscontext_sid) {
 681
 682                 rc = may_context_mount_sb_relabel(fscontext_sid, sbsec, tsec);
 683                 if (rc)
 684                         goto out;
 685
 686                 sbsec->sid = fscontext_sid;
 687         }
 688
 689         /*
 690          * Switch to using mount point labeling behavior.
 691          * sets the label used on all file below the mountpoint, and will set
 692          * the superblock context if not already set.
 693          */
 694         if (context_sid) {
 695                 if (!fscontext_sid) {
 696                         rc = may_context_mount_sb_relabel(context_sid, sbsec, tsec);
 697                         if (rc)
 698                                 goto out;
 699                         sbsec->sid = context_sid;
 700                 } else {
 701                         rc = may_context_mount_inode_relabel(context_sid, sbsec, tsec);
 702                         if (rc)
 703                                 goto out;
 704                 }
 705                 if (!rootcontext_sid)
 706                         rootcontext_sid = context_sid;
 707
 708                 sbsec->mntpoint_sid = context_sid;
 709                 sbsec->behavior = SECURITY_FS_USE_MNTPOINT;
 710         }
 711
 712         if (rootcontext_sid) {
 713                 rc = may_context_mount_inode_relabel(rootcontext_sid, sbsec, tsec);
 714                 if (rc)
 715                         goto out;
 716
 717                 root_isec->sid = rootcontext_sid;
 718                 root_isec->initialized = 1;
 719         }
 720
 721         if (defcontext_sid) {
 722                 if (sbsec->behavior != SECURITY_FS_USE_XATTR) {
 723                         rc = -EINVAL;
 724                         printk(KERN_WARNING "SELinux: defcontext option is "
 725                                "invalid for this filesystem type\n");
 726                         goto out;
 727                 }
 728
 729                 if (defcontext_sid != sbsec->def_sid) {
 730                         rc = may_context_mount_inode_relabel(defcontext_sid,
 731                                                              sbsec, tsec);
 732                         if (rc)
 733                                 goto out;
 734                 }
 735
 736                 sbsec->def_sid = defcontext_sid;
 737         }
 738
 739         rc = sb_finish_set_opts(sb);
 740 out:
 741         mutex_unlock(&sbsec->lock);
 742         return rc;
 743 out_double_mount:
 744         rc = -EINVAL;
 745         printk(KERN_WARNING "SELinux: mount invalid.  Same superblock, different "
 746                "security settings for (dev %s, type %s)\n", sb->s_id, name);
 747         goto out;
 748 }
 749
 750 static void selinux_sb_clone_mnt_opts(const struct super_block *oldsb,
 751                                         struct super_block *newsb)
 752 {
 753         const struct superblock_security_struct *oldsbsec = oldsb->s_security;
 754         struct superblock_security_struct *newsbsec = newsb->s_security;
 755
 756         int set_fscontext =     (oldsbsec->flags & FSCONTEXT_MNT);
 757         int set_context =       (oldsbsec->flags & CONTEXT_MNT);
 758         int set_rootcontext =   (oldsbsec->flags & ROOTCONTEXT_MNT);
 759
 760         /*
 761          * if the parent was able to be mounted it clearly had no special lsm
 762          * mount options.  thus we can safely put this sb on the list and deal
 763          * with it later
 764          */
 765         if (!ss_initialized) {
 766                 spin_lock(&sb_security_lock);
 767                 if (list_empty(&newsbsec->list))
 768                         list_add(&newsbsec->list, &superblock_security_head);
 769                 spin_unlock(&sb_security_lock);
 770                 return;
 771         }
 772
 773         /* how can we clone if the old one wasn't set up?? */
 774         BUG_ON(!oldsbsec->initialized);
 775
 776         /* if fs is reusing a sb, just let its options stand... */
 777         if (newsbsec->initialized)
 778                 return;
 779
 780         mutex_lock(&newsbsec->lock);
 781
 782         newsbsec->flags = oldsbsec->flags;
 783
 784         newsbsec->sid = oldsbsec->sid;
 785         newsbsec->def_sid = oldsbsec->def_sid;
 786         newsbsec->behavior = oldsbsec->behavior;
 787
 788         if (set_context) {
 789                 u32 sid = oldsbsec->mntpoint_sid;
 790
 791                 if (!set_fscontext)
 792                         newsbsec->sid = sid;
 793                 if (!set_rootcontext) {
 794                         struct inode *newinode = newsb->s_root->d_inode;
 795                         struct inode_security_struct *newisec = newinode->i_security;
 796                         newisec->sid = sid;
 797                 }
 798                 newsbsec->mntpoint_sid = sid;
 799         }
 800         if (set_rootcontext) {
 801                 const struct inode *oldinode = oldsb->s_root->d_inode;
 802                 const struct inode_security_struct *oldisec = oldinode->i_security;
 803                 struct inode *newinode = newsb->s_root->d_inode;
 804                 struct inode_security_struct *newisec = newinode->i_security;
 805
 806                 newisec->sid = oldisec->sid;
 807         }
 808
 809         sb_finish_set_opts(newsb);
 810         mutex_unlock(&newsbsec->lock);
 811 }
 812
 813 static int selinux_parse_opts_str(char *options,
 814                                   struct security_mnt_opts *opts)
 815 {
 816         char *p;
 817         char *context = NULL, *defcontext = NULL;
 818         char *fscontext = NULL, *rootcontext = NULL;
 819         int rc, num_mnt_opts = 0;
 820
 821         opts->num_mnt_opts = 0;
 822
 823         /* Standard string-based options. */
 824         while ((p = strsep(&options, "|")) != NULL) {
 825                 int token;
 826                 substring_t args[MAX_OPT_ARGS];
 827
 828                 if (!*p)
 829                         continue;
 830
 831                 token = match_token(p, tokens, args);
 832
 833                 switch (token) {
 834                 case Opt_context:
 835                         if (context || defcontext) {
 836                                 rc = -EINVAL;
 837                                 printk(KERN_WARNING SEL_MOUNT_FAIL_MSG);
 838                                 goto out_err;
 839                         }
 840                         context = match_strdup(&args[0]);
 841                         if (!context) {
 842                                 rc = -ENOMEM;
 843                                 goto out_err;
 844                         }
 845                         break;
 846
 847                 case Opt_fscontext:
 848                         if (fscontext) {
 849                                 rc = -EINVAL;
 850                                 printk(KERN_WARNING SEL_MOUNT_FAIL_MSG);
 851                                 goto out_err;
 852                         }
 853                         fscontext = match_strdup(&args[0]);
 854                         if (!fscontext) {
 855                                 rc = -ENOMEM;
 856                                 goto out_err;
 857                         }
 858                         break;
 859
 860                 case Opt_rootcontext:
 861                         if (rootcontext) {
 862                                 rc = -EINVAL;
 863                                 printk(KERN_WARNING SEL_MOUNT_FAIL_MSG);
 864                                 goto out_err;
 865                         }
 866                         rootcontext = match_strdup(&args[0]);
 867                         if (!rootcontext) {
 868                                 rc = -ENOMEM;
 869                                 goto out_err;
 870                         }
 871                         break;
 872
 873                 case Opt_defcontext:
 874                         if (context || defcontext) {
 875                                 rc = -EINVAL;
 876                                 printk(KERN_WARNING SEL_MOUNT_FAIL_MSG);
 877                                 goto out_err;
 878                         }
 879                         defcontext = match_strdup(&args[0]);
 880                         if (!defcontext) {
 881                                 rc = -ENOMEM;
 882                                 goto out_err;
 883                         }
 884                         break;
 885
 886                 default:
 887                         rc = -EINVAL;
 888                         printk(KERN_WARNING "SELinux:  unknown mount option\n");
 889                         goto out_err;
 890
 891                 }
 892         }
 893
 894         rc = -ENOMEM;
 895         opts->mnt_opts = kcalloc(NUM_SEL_MNT_OPTS, sizeof(char *), GFP_ATOMIC);
 896         if (!opts->mnt_opts)
 897                 goto out_err;
 898
 899         opts->mnt_opts_flags = kcalloc(NUM_SEL_MNT_OPTS, sizeof(int), GFP_ATOMIC);
 900         if (!opts->mnt_opts_flags) {
 901                 kfree(opts->mnt_opts);
 902                 goto out_err;
 903         }
 904
 905         if (fscontext) {
 906                 opts->mnt_opts[num_mnt_opts] = fscontext;
 907                 opts->mnt_opts_flags[num_mnt_opts++] = FSCONTEXT_MNT;
 908         }
 909         if (context) {
 910                 opts->mnt_opts[num_mnt_opts] = context;
 911                 opts->mnt_opts_flags[num_mnt_opts++] = CONTEXT_MNT;
 912         }
 913         if (rootcontext) {
 914                 opts->mnt_opts[num_mnt_opts] = rootcontext;
 915                 opts->mnt_opts_flags[num_mnt_opts++] = ROOTCONTEXT_MNT;
 916         }
 917         if (defcontext) {
 918                 opts->mnt_opts[num_mnt_opts] = defcontext;
 919                 opts->mnt_opts_flags[num_mnt_opts++] = DEFCONTEXT_MNT;
 920         }
 921
 922         opts->num_mnt_opts = num_mnt_opts;
 923         return 0;
 924
 925 out_err:
 926         kfree(context);
 927         kfree(defcontext);
 928         kfree(fscontext);
 929         kfree(rootcontext);
 930         return rc;
 931 }
 932 /*
 933  * string mount options parsing and call set the sbsec
 934  */
 935 static int superblock_doinit(struct super_block *sb, void *data)
 936 {
 937         int rc = 0;
 938         char *options = data;
 939         struct security_mnt_opts opts;
 940
 941         security_init_mnt_opts(&opts);
 942
 943         if (!data)
 944                 goto out;
 945
 946         BUG_ON(sb->s_type->fs_flags & FS_BINARY_MOUNTDATA);
 947
 948         rc = selinux_parse_opts_str(options, &opts);
 949         if (rc)
 950                 goto out_err;
 951
 952 out:
 953         rc = selinux_set_mnt_opts(sb, &opts);
 954
 955 out_err:
 956         security_free_mnt_opts(&opts);
 957         return rc;
 958 }
 959
 960 static void selinux_write_opts(struct seq_file *m,
 961                                struct security_mnt_opts *opts)
 962 {
 963         int i;
 964         char *prefix;
 965
 966         for (i = 0; i < opts->num_mnt_opts; i++) {
 967                 char *has_comma = strchr(opts->mnt_opts[i], ',');
 968
 969                 switch (opts->mnt_opts_flags[i]) {
 970                 case CONTEXT_MNT:
 971                         prefix = CONTEXT_STR;
 972                         break;
 973                 case FSCONTEXT_MNT:
 974                         prefix = FSCONTEXT_STR;
 975                         break;
 976                 case ROOTCONTEXT_MNT:
 977                         prefix = ROOTCONTEXT_STR;
 978                         break;
 979                 case DEFCONTEXT_MNT:
 980                         prefix = DEFCONTEXT_STR;
 981                         break;
 982                 default:
 983                         BUG();
 984                 };
 985                 /* we need a comma before each option */
 986                 seq_putc(m, ',');
 987                 seq_puts(m, prefix);
 988                 if (has_comma)
 989                         seq_putc(m, '\"');
 990                 seq_puts(m, opts->mnt_opts[i]);
 991                 if (has_comma)
 992                         seq_putc(m, '\"');
 993         }
 994 }
 995
 996 static int selinux_sb_show_options(struct seq_file *m, struct super_block *sb)
 997 {
 998         struct security_mnt_opts opts;
 999         int rc;
1000
1001         rc = selinux_get_mnt_opts(sb, &opts);
1002         if (rc) {
1003                 /* before policy load we may get EINVAL, don't show anything */
1004                 if (rc == -EINVAL)
1005                         rc = 0;
1006                 return rc;
1007         }
1008
1009         selinux_write_opts(m, &opts);
1010
1011         security_free_mnt_opts(&opts);
1012
1013         return rc;
1014 }
1015
1016 static inline u16 inode_mode_to_security_class(umode_t mode)
1017 {
1018         switch (mode & S_IFMT) {
1019         case S_IFSOCK:
1020                 return SECCLASS_SOCK_FILE;
1021         case S_IFLNK:
1022                 return SECCLASS_LNK_FILE;
1023         case S_IFREG:
1024                 return SECCLASS_FILE;
1025         case S_IFBLK:
1026                 return SECCLASS_BLK_FILE;
1027         case S_IFDIR:
1028                 return SECCLASS_DIR;
1029         case S_IFCHR:
1030                 return SECCLASS_CHR_FILE;
1031         case S_IFIFO:
1032                 return SECCLASS_FIFO_FILE;
1033
1034         }
1035
1036         return SECCLASS_FILE;
1037 }
1038
1039 static inline int default_protocol_stream(int protocol)
1040 {
1041         return (protocol == IPPROTO_IP || protocol == IPPROTO_TCP);
1042 }
1043
1044 static inline int default_protocol_dgram(int protocol)
1045 {
1046         return (protocol == IPPROTO_IP || protocol == IPPROTO_UDP);
1047 }
1048
1049 static inline u16 socket_type_to_security_class(int family, int type, int protocol)
1050 {
1051         switch (family) {
1052         case PF_UNIX:
1053                 switch (type) {
1054                 case SOCK_STREAM:
1055                 case SOCK_SEQPACKET:
1056                         return SECCLASS_UNIX_STREAM_SOCKET;
1057                 case SOCK_DGRAM:
1058                         return SECCLASS_UNIX_DGRAM_SOCKET;
1059                 }
1060                 break;
1061         case PF_INET:
1062         case PF_INET6:
1063                 switch (type) {
1064                 case SOCK_STREAM:
1065                         if (default_protocol_stream(protocol))
1066                                 return SECCLASS_TCP_SOCKET;
1067                         else
1068                                 return SECCLASS_RAWIP_SOCKET;
1069                 case SOCK_DGRAM:
1070                         if (default_protocol_dgram(protocol))
1071                                 return SECCLASS_UDP_SOCKET;
1072                         else
1073                                 return SECCLASS_RAWIP_SOCKET;
1074                 case SOCK_DCCP:
1075                         return SECCLASS_DCCP_SOCKET;
1076                 default:
1077                         return SECCLASS_RAWIP_SOCKET;
1078                 }
1079                 break;
1080         case PF_NETLINK:
1081                 switch (protocol) {
1082                 case NETLINK_ROUTE:
1083                         return SECCLASS_NETLINK_ROUTE_SOCKET;
1084                 case NETLINK_FIREWALL:
1085                         return SECCLASS_NETLINK_FIREWALL_SOCKET;
1086                 case NETLINK_INET_DIAG:
1087                         return SECCLASS_NETLINK_TCPDIAG_SOCKET;
1088                 case NETLINK_NFLOG:
1089                         return SECCLASS_NETLINK_NFLOG_SOCKET;
1090                 case NETLINK_XFRM:
1091                         return SECCLASS_NETLINK_XFRM_SOCKET;
1092                 case NETLINK_SELINUX:
1093                         return SECCLASS_NETLINK_SELINUX_SOCKET;
1094                 case NETLINK_AUDIT:
1095                         return SECCLASS_NETLINK_AUDIT_SOCKET;
1096                 case NETLINK_IP6_FW:
1097                         return SECCLASS_NETLINK_IP6FW_SOCKET;
1098                 case NETLINK_DNRTMSG:
1099                         return SECCLASS_NETLINK_DNRT_SOCKET;
1100                 case NETLINK_KOBJECT_UEVENT:
1101                         return SECCLASS_NETLINK_KOBJECT_UEVENT_SOCKET;
1102                 default:
1103                         return SECCLASS_NETLINK_SOCKET;
1104                 }
1105         case PF_PACKET:
1106                 return SECCLASS_PACKET_SOCKET;
1107         case PF_KEY:
1108                 return SECCLASS_KEY_SOCKET;
1109         case PF_APPLETALK:
1110                 return SECCLASS_APPLETALK_SOCKET;
1111         }
1112
1113         return SECCLASS_SOCKET;
1114 }
1115
1116 #ifdef CONFIG_PROC_FS
1117 static int selinux_proc_get_sid(struct proc_dir_entry *de,
1118                                 u16 tclass,
1119                                 u32 *sid)
1120 {
1121         int buflen, rc;
1122         char *buffer, *path, *end;
1123
1124         buffer = (char *)__get_free_page(GFP_KERNEL);
1125         if (!buffer)
1126                 return -ENOMEM;
1127
1128         buflen = PAGE_SIZE;
1129         end = buffer+buflen;
1130         *--end = '\0';
1131         buflen--;
1132         path = end-1;
1133         *path = '/';
1134         while (de && de != de->parent) {
1135                 buflen -= de->namelen + 1;
1136                 if (buflen < 0)
1137                         break;
1138                 end -= de->namelen;
1139                 memcpy(end, de->name, de->namelen);
1140                 *--end = '/';
1141                 path = end;
1142                 de = de->parent;
1143         }
1144         rc = security_genfs_sid("proc", path, tclass, sid);
1145         free_page((unsigned long)buffer);
1146         return rc;
1147 }
1148 #else
1149 static int selinux_proc_get_sid(struct proc_dir_entry *de,
1150                                 u16 tclass,
1151                                 u32 *sid)
1152 {
1153         return -EINVAL;
1154 }
1155 #endif
1156
1157 /* The inode's security attributes must be initialized before first use. */
1158 static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dentry)
1159 {
1160         struct superblock_security_struct *sbsec = NULL;
1161         struct inode_security_struct *isec = inode->i_security;
1162         u32 sid;
1163         struct dentry *dentry;
1164 #define INITCONTEXTLEN 255
1165         char *context = NULL;
1166         unsigned len = 0;
1167         int rc = 0;
1168
1169         if (isec->initialized)
1170                 goto out;
1171
1172         mutex_lock(&isec->lock);
1173         if (isec->initialized)
1174                 goto out_unlock;
1175
1176         sbsec = inode->i_sb->s_security;
1177         if (!sbsec->initialized) {
1178                 /* Defer initialization until selinux_complete_init,
1179                    after the initial policy is loaded and the security
1180                    server is ready to handle calls. */
1181                 spin_lock(&sbsec->isec_lock);
1182                 if (list_empty(&isec->list))
1183                         list_add(&isec->list, &sbsec->isec_head);
1184                 spin_unlock(&sbsec->isec_lock);
1185                 goto out_unlock;
1186         }
1187
1188         switch (sbsec->behavior) {
1189         case SECURITY_FS_USE_XATTR:
1190                 if (!inode->i_op->getxattr) {
1191                         isec->sid = sbsec->def_sid;
1192                         break;
1193                 }
1194
1195                 /* Need a dentry, since the xattr API requires one.
1196                    Life would be simpler if we could just pass the inode. */
1197                 if (opt_dentry) {
1198                         /* Called from d_instantiate or d_splice_alias. */
1199                         dentry = dget(opt_dentry);
1200                 } else {
1201                         /* Called from selinux_complete_init, try to find a dentry. */
1202                         dentry = d_find_alias(inode);
1203                 }
1204                 if (!dentry) {
1205                         printk(KERN_WARNING "SELinux: %s:  no dentry for dev=%s "
1206                                "ino=%ld\n", __func__, inode->i_sb->s_id,
1207                                inode->i_ino);
1208                         goto out_unlock;
1209                 }
1210
1211                 len = INITCONTEXTLEN;
1212                 context = kmalloc(len, GFP_NOFS);
1213                 if (!context) {
1214                         rc = -ENOMEM;
1215                         dput(dentry);
1216                         goto out_unlock;
1217                 }
1218                 rc = inode->i_op->getxattr(dentry, XATTR_NAME_SELINUX,
1219                                            context, len);
1220                 if (rc == -ERANGE) {
1221                         /* Need a larger buffer.  Query for the right size. */
1222                         rc = inode->i_op->getxattr(dentry, XATTR_NAME_SELINUX,
1223                                                    NULL, 0);
1224                         if (rc < 0) {
1225                                 dput(dentry);
1226                                 goto out_unlock;
1227                         }
1228                         kfree(context);
1229                         len = rc;
1230                         context = kmalloc(len, GFP_NOFS);
1231                         if (!context) {
1232                                 rc = -ENOMEM;
1233                                 dput(dentry);
1234                                 goto out_unlock;
1235                         }
1236                         rc = inode->i_op->getxattr(dentry,
1237                                                    XATTR_NAME_SELINUX,
1238                                                    context, len);
1239                 }
1240                 dput(dentry);
1241                 if (rc < 0) {
1242                         if (rc != -ENODATA) {
1243                                 printk(KERN_WARNING "SELinux: %s:  getxattr returned "
1244                                        "%d for dev=%s ino=%ld\n", __func__,
1245                                        -rc, inode->i_sb->s_id, inode->i_ino);
1246                                 kfree(context);
1247                                 goto out_unlock;
1248                         }
1249                         /* Map ENODATA to the default file SID */
1250                         sid = sbsec->def_sid;
1251                         rc = 0;
1252                 } else {
1253                         rc = security_context_to_sid_default(context, rc, &sid,
1254                                                              sbsec->def_sid,
1255                                                              GFP_NOFS);
1256                         if (rc) {
1257                                 printk(KERN_WARNING "SELinux: %s:  context_to_sid(%s) "
1258                                        "returned %d for dev=%s ino=%ld\n",
1259                                        __func__, context, -rc,
1260                                        inode->i_sb->s_id, inode->i_ino);
1261                                 kfree(context);
1262                                 /* Leave with the unlabeled SID */
1263                                 rc = 0;
1264                                 break;
1265                         }
1266                 }
1267                 kfree(context);
1268                 isec->sid = sid;
1269                 break;
1270         case SECURITY_FS_USE_TASK:
1271                 isec->sid = isec->task_sid;
1272                 break;
1273         case SECURITY_FS_USE_TRANS:
1274                 /* Default to the fs SID. */
1275                 isec->sid = sbsec->sid;
1276
1277                 /* Try to obtain a transition SID. */
1278                 isec->sclass = inode_mode_to_security_class(inode->i_mode);
1279                 rc = security_transition_sid(isec->task_sid,
1280                                              sbsec->sid,
1281                                              isec->sclass,
1282                                              &sid);
1283                 if (rc)
1284                         goto out_unlock;
1285                 isec->sid = sid;
1286                 break;
1287         case SECURITY_FS_USE_MNTPOINT:
1288                 isec->sid = sbsec->mntpoint_sid;
1289                 break;
1290         default:
1291                 /* Default to the fs superblock SID. */
1292                 isec->sid = sbsec->sid;
1293
1294                 if (sbsec->proc && !S_ISLNK(inode->i_mode)) {
1295                         struct proc_inode *proci = PROC_I(inode);
1296                         if (proci->pde) {
1297                                 isec->sclass = inode_mode_to_security_class(inode->i_mode);
1298                                 rc = selinux_proc_get_sid(proci->pde,
1299                                                           isec->sclass,
1300                                                           &sid);
1301                                 if (rc)
1302                                         goto out_unlock;
1303                                 isec->sid = sid;
1304                         }
1305                 }
1306                 break;
1307         }
1308
1309         isec->initialized = 1;
1310
1311 out_unlock:
1312         mutex_unlock(&isec->lock);
1313 out:
1314         if (isec->sclass == SECCLASS_FILE)
1315                 isec->sclass = inode_mode_to_security_class(inode->i_mode);
1316         return rc;
1317 }
1318
1319 /* Convert a Linux signal to an access vector. */
1320 static inline u32 signal_to_av(int sig)
1321 {
1322         u32 perm = 0;
1323
1324         switch (sig) {
1325         case SIGCHLD:
1326                 /* Commonly granted from child to parent. */
1327                 perm = PROCESS__SIGCHLD;
1328                 break;
1329         case SIGKILL:
1330                 /* Cannot be caught or ignored */
1331                 perm = PROCESS__SIGKILL;
1332                 break;
1333         case SIGSTOP:
1334                 /* Cannot be caught or ignored */
1335                 perm = PROCESS__SIGSTOP;
1336                 break;
1337         default:
1338                 /* All other signals. */
1339                 perm = PROCESS__SIGNAL;
1340                 break;
1341         }
1342
1343         return perm;
1344 }
1345
1346 /* Check permission betweeen a pair of tasks, e.g. signal checks,
1347    fork check, ptrace check, etc. */
1348 static int task_has_perm(struct task_struct *tsk1,
1349                          struct task_struct *tsk2,
1350                          u32 perms)
1351 {
1352         struct task_security_struct *tsec1, *tsec2;
1353
1354         tsec1 = tsk1->security;
1355         tsec2 = tsk2->security;
1356         return avc_has_perm(tsec1->sid, tsec2->sid,
1357                             SECCLASS_PROCESS, perms, NULL);
1358 }
1359
1360 #if CAP_LAST_CAP > 63
1361 #error Fix SELinux to handle capabilities > 63.
1362 #endif
1363
1364 /* Check whether a task is allowed to use a capability. */
1365 static int task_has_capability(struct task_struct *tsk,
1366                                int cap)
1367 {
1368         struct task_security_struct *tsec;
1369         struct avc_audit_data ad;
1370         u16 sclass;
1371         u32 av = CAP_TO_MASK(cap);
1372
1373         tsec = tsk->security;
1374
1375         AVC_AUDIT_DATA_INIT(&ad, CAP);
1376         ad.tsk = tsk;
1377         ad.u.cap = cap;
1378
1379         switch (CAP_TO_INDEX(cap)) {
1380         case 0:
1381                 sclass = SECCLASS_CAPABILITY;
1382                 break;
1383         case 1:
1384                 sclass = SECCLASS_CAPABILITY2;
1385                 break;
1386         default:
1387                 printk(KERN_ERR
1388                        "SELinux:  out of range capability %d\n", cap);
1389                 BUG();
1390         }
1391         return avc_has_perm(tsec->sid, tsec->sid, sclass, av, &ad);
1392 }
1393
1394 /* Check whether a task is allowed to use a system operation. */
1395 static int task_has_system(struct task_struct *tsk,
1396                            u32 perms)
1397 {
1398         struct task_security_struct *tsec;
1399
1400         tsec = tsk->security;
1401
1402         return avc_has_perm(tsec->sid, SECINITSID_KERNEL,
1403                             SECCLASS_SYSTEM, perms, NULL);
1404 }
1405
1406 /* Check whether a task has a particular permission to an inode.
1407    The 'adp' parameter is optional and allows other audit
1408    data to be passed (e.g. the dentry). */
1409 static int inode_has_perm(struct task_struct *tsk,
1410                           struct inode *inode,
1411                           u32 perms,
1412                           struct avc_audit_data *adp)
1413 {
1414         struct task_security_struct *tsec;
1415         struct inode_security_struct *isec;
1416         struct avc_audit_data ad;
1417
1418         if (unlikely(IS_PRIVATE(inode)))
1419                 return 0;
1420
1421         tsec = tsk->security;
1422         isec = inode->i_security;
1423
1424         if (!adp) {
1425                 adp = &ad;
1426                 AVC_AUDIT_DATA_INIT(&ad, FS);
1427                 ad.u.fs.inode = inode;
1428         }
1429
1430         return avc_has_perm(tsec->sid, isec->sid, isec->sclass, perms, adp);
1431 }
1432
1433 /* Same as inode_has_perm, but pass explicit audit data containing
1434    the dentry to help the auditing code to more easily generate the
1435    pathname if needed. */
1436 static inline int dentry_has_perm(struct task_struct *tsk,
1437                                   struct vfsmount *mnt,
1438                                   struct dentry *dentry,
1439                                   u32 av)
1440 {
1441         struct inode *inode = dentry->d_inode;
1442         struct avc_audit_data ad;
1443         AVC_AUDIT_DATA_INIT(&ad, FS);
1444         ad.u.fs.path.mnt = mnt;
1445         ad.u.fs.path.dentry = dentry;
1446         return inode_has_perm(tsk, inode, av, &ad);
1447 }
1448
1449 /* Check whether a task can use an open file descriptor to
1450    access an inode in a given way.  Check access to the
1451    descriptor itself, and then use dentry_has_perm to
1452    check a particular permission to the file.
1453    Access to the descriptor is implicitly granted if it
1454    has the same SID as the process.  If av is zero, then
1455    access to the file is not checked, e.g. for cases
1456    where only the descriptor is affected like seek. */
1457 static int file_has_perm(struct task_struct *tsk,
1458                                 struct file *file,
1459                                 u32 av)
1460 {
1461         struct task_security_struct *tsec = tsk->security;
1462         struct file_security_struct *fsec = file->f_security;
1463         struct inode *inode = file->f_path.dentry->d_inode;
1464         struct avc_audit_data ad;
1465         int rc;
1466
1467         AVC_AUDIT_DATA_INIT(&ad, FS);
1468         ad.u.fs.path = file->f_path;
1469
1470         if (tsec->sid != fsec->sid) {
1471                 rc = avc_has_perm(tsec->sid, fsec->sid,
1472                                   SECCLASS_FD,
1473                                   FD__USE,
1474                                   &ad);
1475                 if (rc)
1476                         return rc;
1477         }
1478
1479         /* av is zero if only checking access to the descriptor. */
1480         if (av)
1481                 return inode_has_perm(tsk, inode, av, &ad);
1482
1483         return 0;
1484 }
1485
1486 /* Check whether a task can create a file. */
1487 static int may_create(struct inode *dir,
1488                       struct dentry *dentry,
1489                       u16 tclass)
1490 {
1491         struct task_security_struct *tsec;
1492         struct inode_security_struct *dsec;
1493         struct superblock_security_struct *sbsec;
1494         u32 newsid;
1495         struct avc_audit_data ad;
1496         int rc;
1497
1498         tsec = current->security;
1499         dsec = dir->i_security;
1500         sbsec = dir->i_sb->s_security;
1501
1502         AVC_AUDIT_DATA_INIT(&ad, FS);
1503         ad.u.fs.path.dentry = dentry;
1504
1505         rc = avc_has_perm(tsec->sid, dsec->sid, SECCLASS_DIR,
1506                           DIR__ADD_NAME | DIR__SEARCH,
1507                           &ad);
1508         if (rc)
1509                 return rc;
1510
1511         if (tsec->create_sid && sbsec->behavior != SECURITY_FS_USE_MNTPOINT) {
1512                 newsid = tsec->create_sid;
1513         } else {
1514                 rc = security_transition_sid(tsec->sid, dsec->sid, tclass,
1515                                              &newsid);
1516                 if (rc)
1517                         return rc;
1518         }
1519
1520         rc = avc_has_perm(tsec->sid, newsid, tclass, FILE__CREATE, &ad);
1521         if (rc)
1522                 return rc;
1523
1524         return avc_has_perm(newsid, sbsec->sid,
1525                             SECCLASS_FILESYSTEM,
1526                             FILESYSTEM__ASSOCIATE, &ad);
1527 }
1528
1529 /* Check whether a task can create a key. */
1530 static int may_create_key(u32 ksid,
1531                           struct task_struct *ctx)
1532 {
1533         struct task_security_struct *tsec;
1534
1535         tsec = ctx->security;
1536
1537         return avc_has_perm(tsec->sid, ksid, SECCLASS_KEY, KEY__CREATE, NULL);
1538 }
1539
1540 #define MAY_LINK        0
1541 #define MAY_UNLINK      1
1542 #define MAY_RMDIR       2
1543
1544 /* Check whether a task can link, unlink, or rmdir a file/directory. */
1545 static int may_link(struct inode *dir,
1546                     struct dentry *dentry,
1547                     int kind)
1548
1549 {
1550         struct task_security_struct *tsec;
1551         struct inode_security_struct *dsec, *isec;
1552         struct avc_audit_data ad;
1553         u32 av;
1554         int rc;
1555
1556         tsec = current->security;
1557         dsec = dir->i_security;
1558         isec = dentry->d_inode->i_security;
1559
1560         AVC_AUDIT_DATA_INIT(&ad, FS);
1561         ad.u.fs.path.dentry = dentry;
1562
1563         av = DIR__SEARCH;
1564         av |= (kind ? DIR__REMOVE_NAME : DIR__ADD_NAME);
1565         rc = avc_has_perm(tsec->sid, dsec->sid, SECCLASS_DIR, av, &ad);
1566         if (rc)
1567                 return rc;
1568
1569         switch (kind) {
1570         case MAY_LINK:
1571                 av = FILE__LINK;
1572                 break;
1573         case MAY_UNLINK:
1574                 av = FILE__UNLINK;
1575                 break;
1576         case MAY_RMDIR:
1577                 av = DIR__RMDIR;
1578                 break;
1579         default:
1580                 printk(KERN_WARNING "SELinux: %s:  unrecognized kind %d\n",
1581                         __func__, kind);
1582                 return 0;
1583         }
1584
1585         rc = avc_has_perm(tsec->sid, isec->sid, isec->sclass, av, &ad);
1586         return rc;
1587 }
1588
1589 static inline int may_rename(struct inode *old_dir,
1590                              struct dentry *old_dentry,
1591                              struct inode *new_dir,
1592                              struct dentry *new_dentry)
1593 {
1594         struct task_security_struct *tsec;
1595         struct inode_security_struct *old_dsec, *new_dsec, *old_isec, *new_isec;
1596         struct avc_audit_data ad;
1597         u32 av;
1598         int old_is_dir, new_is_dir;
1599         int rc;
1600
1601         tsec = current->security;
1602         old_dsec = old_dir->i_security;
1603         old_isec = old_dentry->d_inode->i_security;
1604         old_is_dir = S_ISDIR(old_dentry->d_inode->i_mode);
1605         new_dsec = new_dir->i_security;
1606
1607         AVC_AUDIT_DATA_INIT(&ad, FS);
1608
1609         ad.u.fs.path.dentry = old_dentry;
1610         rc = avc_has_perm(tsec->sid, old_dsec->sid, SECCLASS_DIR,
1611                           DIR__REMOVE_NAME | DIR__SEARCH, &ad);
1612         if (rc)
1613                 return rc;
1614         rc = avc_has_perm(tsec->sid, old_isec->sid,
1615                           old_isec->sclass, FILE__RENAME, &ad);
1616         if (rc)
1617                 return rc;
1618         if (old_is_dir && new_dir != old_dir) {
1619                 rc = avc_has_perm(tsec->sid, old_isec->sid,
1620                                   old_isec->sclass, DIR__REPARENT, &ad);
1621                 if (rc)
1622                         return rc;
1623         }
1624
1625         ad.u.fs.path.dentry = new_dentry;
1626         av = DIR__ADD_NAME | DIR__SEARCH;
1627         if (new_dentry->d_inode)
1628                 av |= DIR__REMOVE_NAME;
1629         rc = avc_has_perm(tsec->sid, new_dsec->sid, SECCLASS_DIR, av, &ad);
1630         if (rc)
1631                 return rc;
1632         if (new_dentry->d_inode) {
1633                 new_isec = new_dentry->d_inode->i_security;
1634                 new_is_dir = S_ISDIR(new_dentry->d_inode->i_mode);
1635                 rc = avc_has_perm(tsec->sid, new_isec->sid,
1636                                   new_isec->sclass,
1637                                   (new_is_dir ? DIR__RMDIR : FILE__UNLINK), &ad);
1638                 if (rc)
1639                         return rc;
1640         }
1641
1642         return 0;
1643 }
1644
1645 /* Check whether a task can perform a filesystem operation. */
1646 static int superblock_has_perm(struct task_struct *tsk,
1647                                struct super_block *sb,
1648                                u32 perms,
1649                                struct avc_audit_data *ad)
1650 {
1651         struct task_security_struct *tsec;
1652         struct superblock_security_struct *sbsec;
1653
1654         tsec = tsk->security;
1655         sbsec = sb->s_security;
1656         return avc_has_perm(tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM,
1657                             perms, ad);
1658 }
1659
1660 /* Convert a Linux mode and permission mask to an access vector. */
1661 static inline u32 file_mask_to_av(int mode, int mask)
1662 {
1663         u32 av = 0;
1664
1665         if ((mode & S_IFMT) != S_IFDIR) {
1666                 if (mask & MAY_EXEC)
1667                         av |= FILE__EXECUTE;
1668                 if (mask & MAY_READ)
1669                         av |= FILE__READ;
1670
1671                 if (mask & MAY_APPEND)
1672                         av |= FILE__APPEND;
1673                 else if (mask & MAY_WRITE)
1674                         av |= FILE__WRITE;
1675
1676         } else {
1677                 if (mask & MAY_EXEC)
1678                         av |= DIR__SEARCH;
1679                 if (mask & MAY_WRITE)
1680                         av |= DIR__WRITE;
1681                 if (mask & MAY_READ)
1682                         av |= DIR__READ;
1683         }
1684
1685         return av;
1686 }
1687
1688 /*
1689  * Convert a file mask to an access vector and include the correct open
1690  * open permission.
1691  */
1692 static inline u32 open_file_mask_to_av(int mode, int mask)
1693 {
1694         u32 av = file_mask_to_av(mode, mask);
1695
1696         if (selinux_policycap_openperm) {
1697                 /*
1698                  * lnk files and socks do not really have an 'open'
1699                  */
1700                 if (S_ISREG(mode))
1701                         av |= FILE__OPEN;
1702                 else if (S_ISCHR(mode))
1703                         av |= CHR_FILE__OPEN;
1704                 else if (S_ISBLK(mode))
1705                         av |= BLK_FILE__OPEN;
1706                 else if (S_ISFIFO(mode))
1707                         av |= FIFO_FILE__OPEN;
1708                 else if (S_ISDIR(mode))
1709                         av |= DIR__OPEN;
1710                 else
1711                         printk(KERN_ERR "SELinux: WARNING: inside %s with "
1712                                 "unknown mode:%x\n", __func__, mode);
1713         }
1714         return av;
1715 }
1716
1717 /* Convert a Linux file to an access vector. */
1718 static inline u32 file_to_av(struct file *file)
1719 {
1720         u32 av = 0;
1721
1722         if (file->f_mode & FMODE_READ)
1723                 av |= FILE__READ;
1724         if (file->f_mode & FMODE_WRITE) {
1725                 if (file->f_flags & O_APPEND)
1726                         av |= FILE__APPEND;
1727                 else
1728                         av |= FILE__WRITE;
1729         }
1730         if (!av) {
1731                 /*
1732                  * Special file opened with flags 3 for ioctl-only use.
1733                  */
1734                 av = FILE__IOCTL;
1735         }
1736
1737         return av;
1738 }
1739
1740 /* Hook functions begin here. */
1741
1742 static int selinux_ptrace_may_access(struct task_struct *child,
1743                                      unsigned int mode)
1744 {
1745         int rc;
1746
1747         rc = secondary_ops->ptrace_may_access(child, mode);
1748         if (rc)
1749                 return rc;
1750
1751         if (mode == PTRACE_MODE_READ) {
1752                 struct task_security_struct *tsec = current->security;
1753                 struct task_security_struct *csec = child->security;
1754                 return avc_has_perm(tsec->sid, csec->sid,
1755                                     SECCLASS_FILE, FILE__READ, NULL);
1756         }
1757
1758         return task_has_perm(current, child, PROCESS__PTRACE);
1759 }
1760
1761 static int selinux_ptrace_traceme(struct task_struct *parent)
1762 {
1763         int rc;
1764
1765         rc = secondary_ops->ptrace_traceme(parent);
1766         if (rc)
1767                 return rc;
1768
1769         return task_has_perm(parent, current, PROCESS__PTRACE);
1770 }
1771
1772 static int selinux_capget(struct task_struct *target, kernel_cap_t *effective,
1773                           kernel_cap_t *inheritable, kernel_cap_t *permitted)
1774 {
1775         int error;
1776
1777         error = task_has_perm(current, target, PROCESS__GETCAP);
1778         if (error)
1779                 return error;
1780
1781         return secondary_ops->capget(target, effective, inheritable, permitted);
1782 }
1783
1784 static int selinux_capset_check(struct task_struct *target, kernel_cap_t *effective,
1785                                 kernel_cap_t *inheritable, kernel_cap_t *permitted)
1786 {
1787         int error;
1788
1789         error = secondary_ops->capset_check(target, effective, inheritable, permitted);
1790         if (error)
1791                 return error;
1792
1793         return task_has_perm(current, target, PROCESS__SETCAP);
1794 }
1795
1796 static void selinux_capset_set(struct task_struct *target, kernel_cap_t *effective,
1797                                kernel_cap_t *inheritable, kernel_cap_t *permitted)
1798 {
1799         secondary_ops->capset_set(target, effective, inheritable, permitted);
1800 }
1801
1802 static int selinux_capable(struct task_struct *tsk, int cap)
1803 {
1804         int rc;
1805
1806         rc = secondary_ops->capable(tsk, cap);
1807         if (rc)
1808                 return rc;
1809
1810         return task_has_capability(tsk, cap);
1811 }
1812
1813 static int selinux_sysctl_get_sid(ctl_table *table, u16 tclass, u32 *sid)
1814 {
1815         int buflen, rc;
1816         char *buffer, *path, *end;
1817
1818         rc = -ENOMEM;
1819         buffer = (char *)__get_free_page(GFP_KERNEL);
1820         if (!buffer)
1821                 goto out;
1822
1823         buflen = PAGE_SIZE;
1824         end = buffer+buflen;
1825         *--end = '\0';
1826         buflen--;
1827         path = end-1;
1828         *path = '/';
1829         while (table) {
1830                 const char *name = table->procname;
1831                 size_t namelen = strlen(name);
1832                 buflen -= namelen + 1;
1833                 if (buflen < 0)
1834                         goto out_free;
1835                 end -= namelen;
1836                 memcpy(end, name, namelen);
1837                 *--end = '/';
1838                 path = end;
1839                 table = table->parent;
1840         }
1841         buflen -= 4;
1842         if (buflen < 0)
1843                 goto out_free;
1844         end -= 4;
1845         memcpy(end, "/sys", 4);
1846         path = end;
1847         rc = security_genfs_sid("proc", path, tclass, sid);
1848 out_free:
1849         free_page((unsigned long)buffer);
1850 out:
1851         return rc;
1852 }
1853
1854 static int selinux_sysctl(ctl_table *table, int op)
1855 {
1856         int error = 0;
1857         u32 av;
1858         struct task_security_struct *tsec;
1859         u32 tsid;
1860         int rc;
1861
1862         rc = secondary_ops->sysctl(table, op);
1863         if (rc)
1864                 return rc;
1865
1866         tsec = current->security;
1867
1868         rc = selinux_sysctl_get_sid(table, (op == 0001) ?
1869                                     SECCLASS_DIR : SECCLASS_FILE, &tsid);
1870         if (rc) {
1871                 /* Default to the well-defined sysctl SID. */
1872                 tsid = SECINITSID_SYSCTL;
1873         }
1874
1875         /* The op values are "defined" in sysctl.c, thereby creating
1876          * a bad coupling between this module and sysctl.c */
1877         if (op == 001) {
1878                 error = avc_has_perm(tsec->sid, tsid,
1879                                      SECCLASS_DIR, DIR__SEARCH, NULL);
1880         } else {
1881                 av = 0;
1882                 if (op & 004)
1883                         av |= FILE__READ;
1884                 if (op & 002)
1885                         av |= FILE__WRITE;
1886                 if (av)
1887                         error = avc_has_perm(tsec->sid, tsid,
1888                                              SECCLASS_FILE, av, NULL);
1889         }
1890
1891         return error;
1892 }
1893
1894 static int selinux_quotactl(int cmds, int type, int id, struct super_block *sb)
1895 {
1896         int rc = 0;
1897
1898         if (!sb)
1899                 return 0;
1900
1901         switch (cmds) {
1902         case Q_SYNC:
1903         case Q_QUOTAON:
1904         case Q_QUOTAOFF:
1905         case Q_SETINFO:
1906         case Q_SETQUOTA:
1907                 rc = superblock_has_perm(current, sb, FILESYSTEM__QUOTAMOD,
1908                                          NULL);
1909                 break;
1910         case Q_GETFMT:
1911         case Q_GETINFO:
1912         case Q_GETQUOTA:
1913                 rc = superblock_has_perm(current, sb, FILESYSTEM__QUOTAGET,
1914                                          NULL);
1915                 break;
1916         default:
1917                 rc = 0;  /* let the kernel handle invalid cmds */
1918                 break;
1919         }
1920         return rc;
1921 }
1922
1923 static int selinux_quota_on(struct dentry *dentry)
1924 {
1925         return dentry_has_perm(current, NULL, dentry, FILE__QUOTAON);
1926 }
1927
1928 static int selinux_syslog(int type)
1929 {
1930         int rc;
1931
1932         rc = secondary_ops->syslog(type);
1933         if (rc)
1934                 return rc;
1935
1936         switch (type) {
1937         case 3:         /* Read last kernel messages */
1938         case 10:        /* Return size of the log buffer */
1939                 rc = task_has_system(current, SYSTEM__SYSLOG_READ);
1940                 break;
1941         case 6:         /* Disable logging to console */
1942         case 7:         /* Enable logging to console */
1943         case 8:         /* Set level of messages printed to console */
1944                 rc = task_has_system(current, SYSTEM__SYSLOG_CONSOLE);
1945                 break;
1946         case 0:         /* Close log */
1947         case 1:         /* Open log */
1948         case 2:         /* Read from log */
1949         case 4:         /* Read/clear last kernel messages */
1950         case 5:         /* Clear ring buffer */
1951         default:
1952                 rc = task_has_system(current, SYSTEM__SYSLOG_MOD);
1953                 break;
1954         }
1955         return rc;
1956 }
1957
1958 /*
1959  * Check that a process has enough memory to allocate a new virtual
1960  * mapping. 0 means there is enough memory for the allocation to
1961  * succeed and -ENOMEM implies there is not.
1962  *
1963  * Note that secondary_ops->capable and task_has_perm_noaudit return 0
1964  * if the capability is granted, but __vm_enough_memory requires 1 if
1965  * the capability is granted.
1966  *
1967  * Do not audit the selinux permission check, as this is applied to all
1968  * processes that allocate mappings.
1969  */
1970 static int selinux_vm_enough_memory(struct mm_struct *mm, long pages)
1971 {
1972         int rc, cap_sys_admin = 0;
1973         struct task_security_struct *tsec = current->security;
1974
1975         rc = secondary_ops->capable(current, CAP_SYS_ADMIN);
1976         if (rc == 0)
1977                 rc = avc_has_perm_noaudit(tsec->sid, tsec->sid,
1978                                           SECCLASS_CAPABILITY,
1979                                           CAP_TO_MASK(CAP_SYS_ADMIN),
1980                                           0,
1981                                           NULL);
1982
1983         if (rc == 0)
1984                 cap_sys_admin = 1;
1985
1986         return __vm_enough_memory(mm, pages, cap_sys_admin);
1987 }
1988
1989 /* binprm security operations */
1990
1991 static int selinux_bprm_alloc_security(struct linux_binprm *bprm)
1992 {
1993         struct bprm_security_struct *bsec;
1994
1995         bsec = kzalloc(sizeof(struct bprm_security_struct), GFP_KERNEL);
1996         if (!bsec)
1997                 return -ENOMEM;
1998
1999         bsec->sid = SECINITSID_UNLABELED;
2000         bsec->set = 0;
2001
2002         bprm->security = bsec;
2003         return 0;
2004 }
2005
2006 static int selinux_bprm_set_security(struct linux_binprm *bprm)
2007 {
2008         struct task_security_struct *tsec;
2009         struct inode *inode = bprm->file->f_path.dentry->d_inode;
2010         struct inode_security_struct *isec;
2011         struct bprm_security_struct *bsec;
2012         u32 newsid;
2013         struct avc_audit_data ad;
2014         int rc;
2015
2016         rc = secondary_ops->bprm_set_security(bprm);
2017         if (rc)
2018                 return rc;
2019
2020         bsec = bprm->security;
2021
2022         if (bsec->set)
2023                 return 0;
2024
2025         tsec = current->security;
2026         isec = inode->i_security;
2027
2028         /* Default to the current task SID. */
2029         bsec->sid = tsec->sid;
2030
2031         /* Reset fs, key, and sock SIDs on execve. */
2032         tsec->create_sid = 0;
2033         tsec->keycreate_sid = 0;
2034         tsec->sockcreate_sid = 0;
2035
2036         if (tsec->exec_sid) {
2037                 newsid = tsec->exec_sid;
2038                 /* Reset exec SID on execve. */
2039                 tsec->exec_sid = 0;
2040         } else {
2041                 /* Check for a default transition on this program. */
2042                 rc = security_transition_sid(tsec->sid, isec->sid,
2043                                              SECCLASS_PROCESS, &newsid);
2044                 if (rc)
2045                         return rc;
2046         }
2047
2048         AVC_AUDIT_DATA_INIT(&ad, FS);
2049         ad.u.fs.path = bprm->file->f_path;
2050
2051         if (bprm->file->f_path.mnt->mnt_flags & MNT_NOSUID)
2052                 newsid = tsec->sid;
2053
2054         if (tsec->sid == newsid) {
2055                 rc = avc_has_perm(tsec->sid, isec->sid,
2056                                   SECCLASS_FILE, FILE__EXECUTE_NO_TRANS, &ad);
2057                 if (rc)
2058                         return rc;
2059         } else {
2060                 /* Check permissions for the transition. */
2061                 rc = avc_has_perm(tsec->sid, newsid,
2062                                   SECCLASS_PROCESS, PROCESS__TRANSITION, &ad);
2063                 if (rc)
2064                         return rc;
2065
2066                 rc = avc_has_perm(newsid, isec->sid,
2067                                   SECCLASS_FILE, FILE__ENTRYPOINT, &ad);
2068                 if (rc)
2069                         return rc;
2070
2071                 /* Clear any possibly unsafe personality bits on exec: */
2072                 current->personality &= ~PER_CLEAR_ON_SETID;
2073
2074                 /* Set the security field to the new SID. */
2075                 bsec->sid = newsid;
2076         }
2077
2078         bsec->set = 1;
2079         return 0;
2080 }
2081
2082 static int selinux_bprm_check_security(struct linux_binprm *bprm)
2083 {
2084         return secondary_ops->bprm_check_security(bprm);
2085 }
2086
2087
2088 static int selinux_bprm_secureexec(struct linux_binprm *bprm)
2089 {
2090         struct task_security_struct *tsec = current->security;
2091         int atsecure = 0;
2092
2093         if (tsec->osid != tsec->sid) {
2094                 /* Enable secure mode for SIDs transitions unless
2095                    the noatsecure permission is granted between
2096                    the two SIDs, i.e. ahp returns 0. */
2097                 atsecure = avc_has_perm(tsec->osid, tsec->sid,
2098                                          SECCLASS_PROCESS,
2099                                          PROCESS__NOATSECURE, NULL);
2100         }
2101
2102         return (atsecure || secondary_ops->bprm_secureexec(bprm));
2103 }
2104
2105 static void selinux_bprm_free_security(struct linux_binprm *bprm)
2106 {
2107         kfree(bprm->security);
2108         bprm->security = NULL;
2109 }
2110
2111 extern struct vfsmount *selinuxfs_mount;
2112 extern struct dentry *selinux_null;
2113
2114 /* Derived from fs/exec.c:flush_old_files. */
2115 static inline void flush_unauthorized_files(struct files_struct *files)
2116 {
2117         struct avc_audit_data ad;
2118         struct file *file, *devnull = NULL;
2119         struct tty_struct *tty;
2120         struct fdtable *fdt;
2121         long j = -1;
2122         int drop_tty = 0;
2123
2124         mutex_lock(&tty_mutex);
2125         tty = get_current_tty();
2126         if (tty) {
2127                 file_list_lock();
2128                 file = list_entry(tty->tty_files.next, typeof(*file), f_u.fu_list);
2129                 if (file) {
2130                         /* Revalidate access to controlling tty.
2131                            Use inode_has_perm on the tty inode directly rather
2132                            than using file_has_perm, as this particular open
2133                            file may belong to another process and we are only
2134                            interested in the inode-based check here. */
2135                         struct inode *inode = file->f_path.dentry->d_inode;
2136                         if (inode_has_perm(current, inode,
2137                                            FILE__READ | FILE__WRITE, NULL)) {
2138                                 drop_tty = 1;
2139                         }
2140                 }
2141                 file_list_unlock();
2142         }
2143         mutex_unlock(&tty_mutex);
2144         /* Reset controlling tty. */
2145         if (drop_tty)
2146                 no_tty();
2147
2148         /* Revalidate access to inherited open files. */
2149
2150         AVC_AUDIT_DATA_INIT(&ad, FS);
2151
2152         spin_lock(&files->file_lock);
2153         for (;;) {
2154                 unsigned long set, i;
2155                 int fd;
2156
2157                 j++;
2158                 i = j * __NFDBITS;
2159                 fdt = files_fdtable(files);
2160                 if (i >= fdt->max_fds)
2161                         break;
2162                 set = fdt->open_fds->fds_bits[j];
2163                 if (!set)
2164                         continue;
2165                 spin_unlock(&files->file_lock);
2166                 for ( ; set ; i++, set >>= 1) {
2167                         if (set & 1) {
2168                                 file = fget(i);
2169                                 if (!file)
2170                                         continue;
2171                                 if (file_has_perm(current,
2172                                                   file,
2173                                                   file_to_av(file))) {
2174                                         sys_close(i);
2175                                         fd = get_unused_fd();
2176                                         if (fd != i) {
2177                                                 if (fd >= 0)
2178                                                         put_unused_fd(fd);
2179                                                 fput(file);
2180                                                 continue;
2181                                         }
2182                                         if (devnull) {
2183                                                 get_file(devnull);
2184                                         } else {
2185                                                 devnull = dentry_open(dget(selinux_null), mntget(selinuxfs_mount), O_RDWR);
2186                                                 if (IS_ERR(devnull)) {
2187                                                         devnull = NULL;
2188                                                         put_unused_fd(fd);
2189                                                         fput(file);
2190                                                         continue;
2191                                                 }
2192                                         }
2193                                         fd_install(fd, devnull);
2194                                 }
2195                                 fput(file);
2196                         }
2197                 }
2198                 spin_lock(&files->file_lock);
2199
2200         }
2201         spin_unlock(&files->file_lock);
2202 }
2203
2204 static void selinux_bprm_apply_creds(struct linux_binprm *bprm, int unsafe)
2205 {
2206         struct task_security_struct *tsec;
2207         struct bprm_security_struct *bsec;
2208         u32 sid;
2209         int rc;
2210
2211         secondary_ops->bprm_apply_creds(bprm, unsafe);
2212
2213         tsec = current->security;
2214
2215         bsec = bprm->security;
2216         sid = bsec->sid;
2217
2218         tsec->osid = tsec->sid;
2219         bsec->unsafe = 0;
2220         if (tsec->sid != sid) {
2221                 /* Check for shared state.  If not ok, leave SID
2222                    unchanged and kill. */
2223                 if (unsafe & LSM_UNSAFE_SHARE) {
2224                         rc = avc_has_perm(tsec->sid, sid, SECCLASS_PROCESS,
2225                                         PROCESS__SHARE, NULL);
2226                         if (rc) {
2227                                 bsec->unsafe = 1;
2228                                 return;
2229                         }
2230                 }
2231
2232                 /* Check for ptracing, and update the task SID if ok.
2233                    Otherwise, leave SID unchanged and kill. */
2234                 if (unsafe & (LSM_UNSAFE_PTRACE | LSM_UNSAFE_PTRACE_CAP)) {
2235                         struct task_struct *tracer;
2236                         struct task_security_struct *sec;
2237                         u32 ptsid = 0;
2238
2239                         rcu_read_lock();
2240                         tracer = tracehook_tracer_task(current);
2241                         if (likely(tracer != NULL)) {
2242                                 sec = tracer->security;
2243                                 ptsid = sec->sid;
2244                         }
2245                         rcu_read_unlock();
2246
2247                         if (ptsid != 0) {
2248                                 rc = avc_has_perm(ptsid, sid, SECCLASS_PROCESS,
2249                                                   PROCESS__PTRACE, NULL);
2250                                 if (rc) {
2251                                         bsec->unsafe = 1;
2252                                         return;
2253                                 }
2254                         }
2255                 }
2256                 tsec->sid = sid;
2257         }
2258 }
2259
2260 /*
2261  * called after apply_creds without the task lock held
2262  */
2263 static void selinux_bprm_post_apply_creds(struct linux_binprm *bprm)
2264 {
2265         struct task_security_struct *tsec;
2266         struct rlimit *rlim, *initrlim;
2267         struct itimerval itimer;
2268         struct bprm_security_struct *bsec;
2269         int rc, i;
2270
2271         tsec = current->security;
2272         bsec = bprm->security;
2273
2274         if (bsec->unsafe) {
2275                 force_sig_specific(SIGKILL, current);
2276                 return;
2277         }
2278         if (tsec->osid == tsec->sid)
2279                 return;
2280
2281         /* Close files for which the new task SID is not authorized. */
2282         flush_unauthorized_files(current->files);
2283
2284         /* Check whether the new SID can inherit signal state
2285            from the old SID.  If not, clear itimers to avoid
2286            subsequent signal generation and flush and unblock
2287            signals. This must occur _after_ the task SID has
2288           been updated so that any kill done after the flush
2289           will be checked against the new SID. */
2290         rc = avc_has_perm(tsec->osid, tsec->sid, SECCLASS_PROCESS,
2291                           PROCESS__SIGINH, NULL);
2292         if (rc) {
2293                 memset(&itimer, 0, sizeof itimer);
2294                 for (i = 0; i < 3; i++)
2295                         do_setitimer(i, &itimer, NULL);
2296                 flush_signals(current);
2297                 spin_lock_irq(&current->sighand->siglock);
2298                 flush_signal_handlers(current, 1);
2299                 sigemptyset(&current->blocked);
2300                 recalc_sigpending();
2301                 spin_unlock_irq(&current->sighand->siglock);
2302         }
2303
2304         /* Always clear parent death signal on SID transitions. */
2305         current->pdeath_signal = 0;
2306
2307         /* Check whether the new SID can inherit resource limits
2308            from the old SID.  If not, reset all soft limits to
2309            the lower of the current task's hard limit and the init
2310            task's soft limit.  Note that the setting of hard limits
2311            (even to lower them) can be controlled by the setrlimit
2312            check. The inclusion of the init task's soft limit into
2313            the computation is to avoid resetting soft limits higher
2314            than the default soft limit for cases where the default
2315            is lower than the hard limit, e.g. RLIMIT_CORE or
2316            RLIMIT_STACK.*/
2317         rc = avc_has_perm(tsec->osid, tsec->sid, SECCLASS_PROCESS,
2318                           PROCESS__RLIMITINH, NULL);
2319         if (rc) {
2320                 for (i = 0; i < RLIM_NLIMITS; i++) {
2321                         rlim = current->signal->rlim + i;
2322                         initrlim = init_task.signal->rlim+i;
2323                         rlim->rlim_cur = min(rlim->rlim_max, initrlim->rlim_cur);
2324                 }
2325                 if (current->signal->rlim[RLIMIT_CPU].rlim_cur != RLIM_INFINITY) {
2326                         /*
2327                          * This will cause RLIMIT_CPU calculations
2328                          * to be refigured.
2329                          */
2330                         current->it_prof_expires = jiffies_to_cputime(1);
2331                 }
2332         }
2333
2334         /* Wake up the parent if it is waiting so that it can
2335            recheck wait permission to the new task SID. */
2336         wake_up_interruptible(&current->parent->signal->wait_chldexit);
2337 }
2338
2339 /* superblock security operations */
2340
2341 static int selinux_sb_alloc_security(struct super_block *sb)
2342 {
2343         return superblock_alloc_security(sb);
2344 }
2345
2346 static void selinux_sb_free_security(struct super_block *sb)
2347 {
2348         superblock_free_security(sb);
2349 }
2350
2351 static inline int match_prefix(char *prefix, int plen, char *option, int olen)
2352 {
2353         if (plen > olen)
2354                 return 0;
2355
2356         return !memcmp(prefix, option, plen);
2357 }
2358
2359 static inline int selinux_option(char *option, int len)
2360 {
2361         return (match_prefix(CONTEXT_STR, sizeof(CONTEXT_STR)-1, option, len) ||
2362                 match_prefix(FSCONTEXT_STR, sizeof(FSCONTEXT_STR)-1, option, len) ||
2363                 match_prefix(DEFCONTEXT_STR, sizeof(DEFCONTEXT_STR)-1, option, len) ||
2364                 match_prefix(ROOTCONTEXT_STR, sizeof(ROOTCONTEXT_STR)-1, option, len));
2365 }
2366
2367 static inline void take_option(char **to, char *from, int *first, int len)
2368 {
2369         if (!*first) {
2370                 **to = ',';
2371                 *to += 1;
2372         } else
2373                 *first = 0;
2374         memcpy(*to, from, len);
2375         *to += len;
2376 }
2377
2378 static inline void take_selinux_option(char **to, char *from, int *first,
2379                                        int len)
2380 {
2381         int current_size = 0;
2382
2383         if (!*first) {
2384                 **to = '|';
2385                 *to += 1;
2386         } else
2387                 *first = 0;
2388
2389         while (current_size < len) {
2390                 if (*from != '"') {
2391                         **to = *from;
2392                         *to += 1;
2393                 }
2394                 from += 1;
2395                 current_size += 1;
2396         }
2397 }
2398
2399 static int selinux_sb_copy_data(char *orig, char *copy)
2400 {
2401         int fnosec, fsec, rc = 0;
2402         char *in_save, *in_curr, *in_end;
2403         char *sec_curr, *nosec_save, *nosec;
2404         int open_quote = 0;
2405
2406         in_curr = orig;
2407         sec_curr = copy;
2408
2409         nosec = (char *)get_zeroed_page(GFP_KERNEL);
2410         if (!nosec) {
2411                 rc = -ENOMEM;
2412                 goto out;
2413         }
2414
2415         nosec_save = nosec;
2416         fnosec = fsec = 1;
2417         in_save = in_end = orig;
2418
2419         do {
2420                 if (*in_end == '"')
2421                         open_quote = !open_quote;
2422                 if ((*in_end == ',' && open_quote == 0) ||
2423                                 *in_end == '\0') {
2424                         int len = in_end - in_curr;
2425
2426                         if (selinux_option(in_curr, len))
2427                                 take_selinux_option(&sec_curr, in_curr, &fsec, len);
2428                         else
2429                                 take_option(&nosec, in_curr, &fnosec, len);
2430
2431                         in_curr = in_end + 1;
2432                 }
2433         } while (*in_end++);
2434
2435         strcpy(in_save, nosec_save);
2436         free_page((unsigned long)nosec_save);
2437 out:
2438         return rc;
2439 }
2440
2441 static int selinux_sb_kern_mount(struct super_block *sb, void *data)
2442 {
2443         struct avc_audit_data ad;
2444         int rc;
2445
2446         rc = superblock_doinit(sb, data);
2447         if (rc)
2448                 return rc;
2449
2450         AVC_AUDIT_DATA_INIT(&ad, FS);
2451         ad.u.fs.path.dentry = sb->s_root;
2452         return superblock_has_perm(current, sb, FILESYSTEM__MOUNT, &ad);
2453 }
2454
2455 static int selinux_sb_statfs(struct dentry *dentry)
2456 {
2457         struct avc_audit_data ad;
2458
2459         AVC_AUDIT_DATA_INIT(&ad, FS);
2460         ad.u.fs.path.dentry = dentry->d_sb->s_root;
2461         return superblock_has_perm(current, dentry->d_sb, FILESYSTEM__GETATTR, &ad);
2462 }
2463
2464 static int selinux_mount(char *dev_name,
2465                          struct path *path,
2466                          char *type,
2467                          unsigned long flags,
2468                          void *data)
2469 {
2470         int rc;
2471
2472         rc = secondary_ops->sb_mount(dev_name, path, type, flags, data);
2473         if (rc)
2474                 return rc;
2475
2476         if (flags & MS_REMOUNT)
2477                 return superblock_has_perm(current, path->mnt->mnt_sb,
2478                                            FILESYSTEM__REMOUNT, NULL);
2479         else
2480                 return dentry_has_perm(current, path->mnt, path->dentry,
2481                                        FILE__MOUNTON);
2482 }
2483
2484 static int selinux_umount(struct vfsmount *mnt, int flags)
2485 {
2486         int rc;
2487
2488         rc = secondary_ops->sb_umount(mnt, flags);
2489         if (rc)
2490                 return rc;
2491
2492         return superblock_has_perm(current, mnt->mnt_sb,
2493                                    FILESYSTEM__UNMOUNT, NULL);
2494 }
2495
2496 /* inode security operations */
2497
2498 static int selinux_inode_alloc_security(struct inode *inode)
2499 {
2500         return inode_alloc_security(inode);
2501 }
2502
2503 static void selinux_inode_free_security(struct inode *inode)
2504 {
2505         inode_free_security(inode);
2506 }
2507
2508 static int selinux_inode_init_security(struct inode *inode, struct inode *dir,
2509                                        char **name, void **value,
2510                                        size_t *len)
2511 {
2512         struct task_security_struct *tsec;
2513         struct inode_security_struct *dsec;
2514         struct superblock_security_struct *sbsec;
2515         u32 newsid, clen;
2516         int rc;
2517         char *namep = NULL, *context;
2518
2519         tsec = current->security;
2520         dsec = dir->i_security;
2521         sbsec = dir->i_sb->s_security;
2522
2523         if (tsec->create_sid && sbsec->behavior != SECURITY_FS_USE_MNTPOINT) {
2524                 newsid = tsec->create_sid;
2525         } else {
2526                 rc = security_transition_sid(tsec->sid, dsec->sid,
2527                                              inode_mode_to_security_class(inode->i_mode),
2528                                              &newsid);
2529                 if (rc) {
2530                         printk(KERN_WARNING "%s:  "
2531                                "security_transition_sid failed, rc=%d (dev=%s "
2532                                "ino=%ld)\n",
2533                                __func__,
2534                                -rc, inode->i_sb->s_id, inode->i_ino);
2535                         return rc;
2536                 }
2537         }
2538
2539         /* Possibly defer initialization to selinux_complete_init. */
2540         if (sbsec->initialized) {
2541                 struct inode_security_struct *isec = inode->i_security;
2542                 isec->sclass = inode_mode_to_security_class(inode->i_mode);
2543                 isec->sid = newsid;
2544                 isec->initialized = 1;
2545         }
2546
2547         if (!ss_initialized || sbsec->behavior == SECURITY_FS_USE_MNTPOINT)
2548                 return -EOPNOTSUPP;
2549
2550         if (name) {
2551                 namep = kstrdup(XATTR_SELINUX_SUFFIX, GFP_NOFS);
2552                 if (!namep)
2553                         return -ENOMEM;
2554                 *name = namep;
2555         }
2556
2557         if (value && len) {
2558                 rc = security_sid_to_context_force(newsid, &context, &clen);
2559                 if (rc) {
2560                         kfree(namep);
2561                         return rc;
2562                 }
2563                 *value = context;
2564                 *len = clen;
2565         }
2566
2567         return 0;
2568 }
2569
2570 static int selinux_inode_create(struct inode *dir, struct dentry *dentry, int mask)
2571 {
2572         return may_create(dir, dentry, SECCLASS_FILE);
2573 }
2574
2575 static int selinux_inode_link(struct dentry *old_dentry, struct inode *dir, struct dentry *new_dentry)
2576 {
2577         int rc;
2578
2579         rc = secondary_ops->inode_link(old_dentry, dir, new_dentry);
2580         if (rc)
2581                 return rc;
2582         return may_link(dir, old_dentry, MAY_LINK);
2583 }
2584
2585 static int selinux_inode_unlink(struct inode *dir, struct dentry *dentry)
2586 {
2587         int rc;
2588
2589         rc = secondary_ops->inode_unlink(dir, dentry);
2590         if (rc)
2591                 return rc;
2592         return may_link(dir, dentry, MAY_UNLINK);
2593 }
2594
2595 static int selinux_inode_symlink(struct inode *dir, struct dentry *dentry, const char *name)
2596 {
2597         return may_create(dir, dentry, SECCLASS_LNK_FILE);
2598 }
2599
2600 static int selinux_inode_mkdir(struct inode *dir, struct dentry *dentry, int mask)
2601 {
2602         return may_create(dir, dentry, SECCLASS_DIR);
2603 }
2604
2605 static int selinux_inode_rmdir(struct inode *dir, struct dentry *dentry)
2606 {
2607         return may_link(dir, dentry, MAY_RMDIR);
2608 }
2609
2610 static int selinux_inode_mknod(struct inode *dir, struct dentry *dentry, int mode, dev_t dev)
2611 {
2612         int rc;
2613
2614         rc = secondary_ops->inode_mknod(dir, dentry, mode, dev);
2615         if (rc)
2616                 return rc;
2617
2618         return may_create(dir, dentry, inode_mode_to_security_class(mode));
2619 }
2620
2621 static int selinux_inode_rename(struct inode *old_inode, struct dentry *old_dentry,
2622                                 struct inode *new_inode, struct dentry *new_dentry)
2623 {
2624         return may_rename(old_inode, old_dentry, new_inode, new_dentry);
2625 }
2626
2627 static int selinux_inode_readlink(struct dentry *dentry)
2628 {
2629         return dentry_has_perm(current, NULL, dentry, FILE__READ);
2630 }
2631
2632 static int selinux_inode_follow_link(struct dentry *dentry, struct nameidata *nameidata)
2633 {
2634         int rc;
2635
2636         rc = secondary_ops->inode_follow_link(dentry, nameidata);
2637         if (rc)
2638                 return rc;
2639         return dentry_has_perm(current, NULL, dentry, FILE__READ);
2640 }
2641
2642 static int selinux_inode_permission(struct inode *inode, int mask)
2643 {
2644         int rc;
2645
2646         rc = secondary_ops->inode_permission(inode, mask);
2647         if (rc)
2648                 return rc;
2649
2650         if (!mask) {
2651                 /* No permission to check.  Existence test. */
2652                 return 0;
2653         }
2654
2655         return inode_has_perm(current, inode,
2656                                open_file_mask_to_av(inode->i_mode, mask), NULL);
2657 }
2658
2659 static int selinux_inode_setattr(struct dentry *dentry, struct iattr *iattr)
2660 {
2661         int rc;
2662
2663         rc = secondary_ops->inode_setattr(dentry, iattr);
2664         if (rc)
2665                 return rc;
2666
2667         if (iattr->ia_valid & ATTR_FORCE)
2668                 return 0;
2669
2670         if (iattr->ia_valid & (ATTR_MODE | ATTR_UID | ATTR_GID |
2671                                ATTR_ATIME_SET | ATTR_MTIME_SET))
2672                 return dentry_has_perm(current, NULL, dentry, FILE__SETATTR);
2673
2674         return dentry_has_perm(current, NULL, dentry, FILE__WRITE);
2675 }
2676
2677 static int selinux_inode_getattr(struct vfsmount *mnt, struct dentry *dentry)
2678 {
2679         return dentry_has_perm(current, mnt, dentry, FILE__GETATTR);
2680 }
2681
2682 static int selinux_inode_setotherxattr(struct dentry *dentry, const char *name)
2683 {
2684         if (!strncmp(name, XATTR_SECURITY_PREFIX,
2685                      sizeof XATTR_SECURITY_PREFIX - 1)) {
2686                 if (!strcmp(name, XATTR_NAME_CAPS)) {
2687                         if (!capable(CAP_SETFCAP))
2688                                 return -EPERM;
2689                 } else if (!capable(CAP_SYS_ADMIN)) {
2690                         /* A different attribute in the security namespace.
2691                            Restrict to administrator. */
2692                         return -EPERM;
2693                 }
2694         }
2695
2696         /* Not an attribute we recognize, so just check the
2697            ordinary setattr permission. */
2698         return dentry_has_perm(current, NULL, dentry, FILE__SETATTR);
2699 }
2700
2701 static int selinux_inode_setxattr(struct dentry *dentry, const char *name,
2702                                   const void *value, size_t size, int flags)
2703 {
2704         struct task_security_struct *tsec = current->security;
2705         struct inode *inode = dentry->d_inode;
2706         struct inode_security_struct *isec = inode->i_security;
2707         struct superblock_security_struct *sbsec;
2708         struct avc_audit_data ad;
2709         u32 newsid;
2710         int rc = 0;
2711
2712         if (strcmp(name, XATTR_NAME_SELINUX))
2713                 return selinux_inode_setotherxattr(dentry, name);
2714
2715         sbsec = inode->i_sb->s_security;
2716         if (sbsec->behavior == SECURITY_FS_USE_MNTPOINT)
2717                 return -EOPNOTSUPP;
2718
2719         if (!is_owner_or_cap(inode))
2720                 return -EPERM;
2721
2722         AVC_AUDIT_DATA_INIT(&ad, FS);
2723         ad.u.fs.path.dentry = dentry;
2724
2725         rc = avc_has_perm(tsec->sid, isec->sid, isec->sclass,
2726                           FILE__RELABELFROM, &ad);
2727         if (rc)
2728                 return rc;
2729
2730         rc = security_context_to_sid(value, size, &newsid);
2731         if (rc == -EINVAL) {
2732                 if (!capable(CAP_MAC_ADMIN))
2733                         return rc;
2734                 rc = security_context_to_sid_force(value, size, &newsid);
2735         }
2736         if (rc)
2737                 return rc;
2738
2739         rc = avc_has_perm(tsec->sid, newsid, isec->sclass,
2740                           FILE__RELABELTO, &ad);
2741         if (rc)
2742                 return rc;
2743
2744         rc = security_validate_transition(isec->sid, newsid, tsec->sid,
2745                                           isec->sclass);
2746         if (rc)
2747                 return rc;
2748
2749         return avc_has_perm(newsid,
2750                             sbsec->sid,
2751                             SECCLASS_FILESYSTEM,
2752                             FILESYSTEM__ASSOCIATE,
2753                             &ad);
2754 }
2755
2756 static void selinux_inode_post_setxattr(struct dentry *dentry, const char *name,
2757                                         const void *value, size_t size,
2758                                         int flags)
2759 {
2760         struct inode *inode = dentry->d_inode;
2761         struct inode_security_struct *isec = inode->i_security;
2762         u32 newsid;
2763         int rc;
2764
2765         if (strcmp(name, XATTR_NAME_SELINUX)) {
2766                 /* Not an attribute we recognize, so nothing to do. */
2767                 return;
2768         }
2769
2770         rc = security_context_to_sid_force(value, size, &newsid);
2771         if (rc) {
2772                 printk(KERN_ERR "SELinux:  unable to map context to SID"
2773                        "for (%s, %lu), rc=%d\n",
2774                        inode->i_sb->s_id, inode->i_ino, -rc);
2775                 return;
2776         }
2777
2778         isec->sid = newsid;
2779         return;
2780 }
2781
2782 static int selinux_inode_getxattr(struct dentry *dentry, const char *name)
2783 {
2784         return dentry_has_perm(current, NULL, dentry, FILE__GETATTR);
2785 }
2786
2787 static int selinux_inode_listxattr(struct dentry *dentry)
2788 {
2789         return dentry_has_perm(current, NULL, dentry, FILE__GETATTR);
2790 }
2791
2792 static int selinux_inode_removexattr(struct dentry *dentry, const char *name)
2793 {
2794         if (strcmp(name, XATTR_NAME_SELINUX))
2795                 return selinux_inode_setotherxattr(dentry, name);
2796
2797         /* No one is allowed to remove a SELinux security label.
2798            You can change the label, but all data must be labeled. */
2799         return -EACCES;
2800 }
2801
2802 /*
2803  * Copy the inode security context value to the user.
2804  *
2805  * Permission check is handled by selinux_inode_getxattr hook.
2806  */
2807 static int selinux_inode_getsecurity(const struct inode *inode, const char *name, void **buffer, bool alloc)
2808 {
2809         u32 size;
2810         int error;
2811         char *context = NULL;
2812         struct task_security_struct *tsec = current->security;
2813         struct inode_security_struct *isec = inode->i_security;
2814
2815         if (strcmp(name, XATTR_SELINUX_SUFFIX))
2816                 return -EOPNOTSUPP;
2817
2818         /*
2819          * If the caller has CAP_MAC_ADMIN, then get the raw context
2820          * value even if it is not defined by current policy; otherwise,
2821          * use the in-core value under current policy.
2822          * Use the non-auditing forms of the permission checks since
2823          * getxattr may be called by unprivileged processes commonly
2824          * and lack of permission just means that we fall back to the
2825          * in-core context value, not a denial.
2826          */
2827         error = secondary_ops->capable(current, CAP_MAC_ADMIN);
2828         if (!error)
2829                 error = avc_has_perm_noaudit(tsec->sid, tsec->sid,
2830                                              SECCLASS_CAPABILITY2,
2831                                              CAPABILITY2__MAC_ADMIN,
2832                                              0,
2833                                              NULL);
2834         if (!error)
2835                 error = security_sid_to_context_force(isec->sid, &context,
2836                                                       &size);
2837         else
2838                 error = security_sid_to_context(isec->sid, &context, &size);
2839         if (error)
2840                 return error;
2841         error = size;
2842         if (alloc) {
2843                 *buffer = context;
2844                 goto out_nofree;
2845         }
2846         kfree(context);
2847 out_nofree:
2848         return error;
2849 }
2850
2851 static int selinux_inode_setsecurity(struct inode *inode, const char *name,
2852                                      const void *value, size_t size, int flags)
2853 {
2854         struct inode_security_struct *isec = inode->i_security;
2855         u32 newsid;
2856         int rc;
2857
2858         if (strcmp(name, XATTR_SELINUX_SUFFIX))
2859                 return -EOPNOTSUPP;
2860
2861         if (!value || !size)
2862                 return -EACCES;
2863
2864         rc = security_context_to_sid((void *)value, size, &newsid);
2865         if (rc)
2866                 return rc;
2867
2868         isec->sid = newsid;
2869         return 0;
2870 }
2871
2872 static int selinux_inode_listsecurity(struct inode *inode, char *buffer, size_t buffer_size)
2873 {
2874         const int len = sizeof(XATTR_NAME_SELINUX);
2875         if (buffer && len <= buffer_size)
2876                 memcpy(buffer, XATTR_NAME_SELINUX, len);
2877         return len;
2878 }
2879
2880 static int selinux_inode_need_killpriv(struct dentry *dentry)
2881 {
2882         return secondary_ops->inode_need_killpriv(dentry);
2883 }
2884
2885 static int selinux_inode_killpriv(struct dentry *dentry)
2886 {
2887         return secondary_ops->inode_killpriv(dentry);
2888 }
2889
2890 static void selinux_inode_getsecid(const struct inode *inode, u32 *secid)
2891 {
2892         struct inode_security_struct *isec = inode->i_security;
2893         *secid = isec->sid;
2894 }
2895
2896 /* file security operations */
2897
2898 static int selinux_revalidate_file_permission(struct file *file, int mask)
2899 {
2900         int rc;
2901         struct inode *inode = file->f_path.dentry->d_inode;
2902
2903         if (!mask) {
2904                 /* No permission to check.  Existence test. */
2905                 return 0;
2906         }
2907
2908         /* file_mask_to_av won't add FILE__WRITE if MAY_APPEND is set */
2909         if ((file->f_flags & O_APPEND) && (mask & MAY_WRITE))
2910                 mask |= MAY_APPEND;
2911
2912         rc = file_has_perm(current, file,
2913                            file_mask_to_av(inode->i_mode, mask));
2914         if (rc)
2915                 return rc;
2916
2917         return selinux_netlbl_inode_permission(inode, mask);
2918 }
2919
2920 static int selinux_file_permission(struct file *file, int mask)
2921 {
2922         struct inode *inode = file->f_path.dentry->d_inode;
2923         struct task_security_struct *tsec = current->security;
2924         struct file_security_struct *fsec = file->f_security;
2925         struct inode_security_struct *isec = inode->i_security;
2926
2927         if (!mask) {
2928                 /* No permission to check.  Existence test. */
2929                 return 0;
2930         }
2931
2932         if (tsec->sid == fsec->sid && fsec->isid == isec->sid
2933             && fsec->pseqno == avc_policy_seqno())
2934                 return selinux_netlbl_inode_permission(inode, mask);
2935
2936         return selinux_revalidate_file_permission(file, mask);
2937 }
2938
2939 static int selinux_file_alloc_security(struct file *file)
2940 {
2941         return file_alloc_security(file);
2942 }
2943
2944 static void selinux_file_free_security(struct file *file)
2945 {
2946         file_free_security(file);
2947 }
2948
2949 static int selinux_file_ioctl(struct file *file, unsigned int cmd,
2950                               unsigned long arg)
2951 {
2952         u32 av = 0;
2953
2954         if (_IOC_DIR(cmd) & _IOC_WRITE)
2955                 av |= FILE__WRITE;
2956         if (_IOC_DIR(cmd) & _IOC_READ)
2957                 av |= FILE__READ;
2958         if (!av)
2959                 av = FILE__IOCTL;
2960
2961         return file_has_perm(current, file, av);
2962 }
2963
2964 static int file_map_prot_check(struct file *file, unsigned long prot, int shared)
2965 {
2966 #ifndef CONFIG_PPC32
2967         if ((prot & PROT_EXEC) && (!file || (!shared && (prot & PROT_WRITE)))) {
2968                 /*
2969                  * We are making executable an anonymous mapping or a
2970                  * private file mapping that will also be writable.
2971                  * This has an additional check.
2972                  */
2973                 int rc = task_has_perm(current, current, PROCESS__EXECMEM);
2974                 if (rc)
2975                         return rc;
2976         }
2977 #endif
2978
2979         if (file) {
2980                 /* read access is always possible with a mapping */
2981                 u32 av = FILE__READ;
2982
2983                 /* write access only matters if the mapping is shared */
2984                 if (shared && (prot & PROT_WRITE))
2985                         av |= FILE__WRITE;
2986
2987                 if (prot & PROT_EXEC)
2988                         av |= FILE__EXECUTE;
2989
2990                 return file_has_perm(current, file, av);
2991         }
2992         return 0;
2993 }
2994
2995 static int selinux_file_mmap(struct file *file, unsigned long reqprot,
2996                              unsigned long prot, unsigned long flags,
2997                              unsigned long addr, unsigned long addr_only)
2998 {
2999         int rc = 0;
3000         u32 sid = ((struct task_security_struct *)(current->security))->sid;
3001
3002         if (addr < mmap_min_addr)
3003                 rc = avc_has_perm(sid, sid, SECCLASS_MEMPROTECT,
3004                                   MEMPROTECT__MMAP_ZERO, NULL);
3005         if (rc || addr_only)
3006                 return rc;
3007
3008         if (selinux_checkreqprot)
3009                 prot = reqprot;
3010
3011         return file_map_prot_check(file, prot,
3012                                    (flags & MAP_TYPE) == MAP_SHARED);
3013 }
3014
3015 static int selinux_file_mprotect(struct vm_area_struct *vma,
3016                                  unsigned long reqprot,
3017                                  unsigned long prot)
3018 {
3019         int rc;
3020
3021         rc = secondary_ops->file_mprotect(vma, reqprot, prot);
3022         if (rc)
3023                 return rc;
3024
3025         if (selinux_checkreqprot)
3026                 prot = reqprot;
3027
3028 #ifndef CONFIG_PPC32
3029         if ((prot & PROT_EXEC) && !(vma->vm_flags & VM_EXEC)) {
3030                 rc = 0;
3031                 if (vma->vm_start >= vma->vm_mm->start_brk &&
3032                     vma->vm_end <= vma->vm_mm->brk) {
3033                         rc = task_has_perm(current, current,
3034                                            PROCESS__EXECHEAP);
3035                 } else if (!vma->vm_file &&
3036                            vma->vm_start <= vma->vm_mm->start_stack &&
3037                            vma->vm_end >= vma->vm_mm->start_stack) {
3038                         rc = task_has_perm(current, current, PROCESS__EXECSTACK);
3039                 } else if (vma->vm_file && vma->anon_vma) {
3040                         /*
3041                          * We are making executable a file mapping that has
3042                          * had some COW done. Since pages might have been
3043                          * written, check ability to execute the possibly
3044                          * modified content.  This typically should only
3045                          * occur for text relocations.
3046                          */
3047                         rc = file_has_perm(current, vma->vm_file,
3048                                            FILE__EXECMOD);
3049                 }
3050                 if (rc)
3051                         return rc;
3052         }
3053 #endif
3054
3055         return file_map_prot_check(vma->vm_file, prot, vma->vm_flags&VM_SHARED);
3056 }
3057
3058 static int selinux_file_lock(struct file *file, unsigned int cmd)
3059 {
3060         return file_has_perm(current, file, FILE__LOCK);
3061 }
3062
3063 static int selinux_file_fcntl(struct file *file, unsigned int cmd,
3064                               unsigned long arg)
3065 {
3066         int err = 0;
3067
3068         switch (cmd) {
3069         case F_SETFL:
3070                 if (!file->f_path.dentry || !file->f_path.dentry->d_inode) {
3071                         err = -EINVAL;
3072                         break;
3073                 }
3074
3075                 if ((file->f_flags & O_APPEND) && !(arg & O_APPEND)) {
3076                         err = file_has_perm(current, file, FILE__WRITE);
3077                         break;
3078                 }
3079                 /* fall through */
3080         case F_SETOWN:
3081         case F_SETSIG:
3082         case F_GETFL:
3083         case F_GETOWN:
3084         case F_GETSIG:
3085                 /* Just check FD__USE permission */
3086                 err = file_has_perm(current, file, 0);
3087                 break;
3088         case F_GETLK:
3089         case F_SETLK:
3090         case F_SETLKW:
3091 #if BITS_PER_LONG == 32
3092         case F_GETLK64:
3093         case F_SETLK64:
3094         case F_SETLKW64:
3095 #endif
3096                 if (!file->f_path.dentry || !file->f_path.dentry->d_inode) {
3097                         err = -EINVAL;
3098                         break;
3099                 }
3100                 err = file_has_perm(current, file, FILE__LOCK);
3101                 break;
3102         }
3103
3104         return err;
3105 }
3106
3107 static int selinux_file_set_fowner(struct file *file)
3108 {
3109         struct task_security_struct *tsec;
3110         struct file_security_struct *fsec;
3111
3112         tsec = current->security;
3113         fsec = file->f_security;
3114         fsec->fown_sid = tsec->sid;
3115
3116         return 0;
3117 }
3118
3119 static int selinux_file_send_sigiotask(struct task_struct *tsk,
3120                                        struct fown_struct *fown, int signum)
3121 {
3122         struct file *file;
3123         u32 perm;
3124         struct task_security_struct *tsec;
3125         struct file_security_struct *fsec;
3126
3127         /* struct fown_struct is never outside the context of a struct file */
3128         file = container_of(fown, struct file, f_owner);
3129
3130         tsec = tsk->security;
3131         fsec = file->f_security;
3132
3133         if (!signum)
3134                 perm = signal_to_av(SIGIO); /* as per send_sigio_to_task */
3135         else
3136                 perm = signal_to_av(signum);
3137
3138         return avc_has_perm(fsec->fown_sid, tsec->sid,
3139                             SECCLASS_PROCESS, perm, NULL);
3140 }
3141
3142 static int selinux_file_receive(struct file *file)
3143 {
3144         return file_has_perm(current, file, file_to_av(file));
3145 }
3146
3147 static int selinux_dentry_open(struct file *file)
3148 {
3149         struct file_security_struct *fsec;
3150         struct inode *inode;
3151         struct inode_security_struct *isec;
3152         inode = file->f_path.dentry->d_inode;
3153         fsec = file->f_security;
3154         isec = inode->i_security;
3155         /*
3156          * Save inode label and policy sequence number
3157          * at open-time so that selinux_file_permission
3158          * can determine whether revalidation is necessary.
3159          * Task label is already saved in the file security
3160          * struct as its SID.
3161          */
3162         fsec->isid = isec->sid;
3163         fsec->pseqno = avc_policy_seqno();
3164         /*
3165          * Since the inode label or policy seqno may have changed
3166          * between the selinux_inode_permission check and the saving
3167          * of state above, recheck that access is still permitted.
3168          * Otherwise, access might never be revalidated against the
3169          * new inode label or new policy.
3170          * This check is not redundant - do not remove.
3171          */
3172         return inode_has_perm(current, inode, file_to_av(file), NULL);
3173 }
3174
3175 /* task security operations */
3176
3177 static int selinux_task_create(unsigned long clone_flags)
3178 {
3179         int rc;
3180
3181         rc = secondary_ops->task_create(clone_flags);
3182         if (rc)
3183                 return rc;
3184
3185         return task_has_perm(current, current, PROCESS__FORK);
3186 }
3187
3188 static int selinux_task_alloc_security(struct task_struct *tsk)
3189 {
3190         struct task_security_struct *tsec1, *tsec2;
3191         int rc;
3192
3193         tsec1 = current->security;
3194
3195         rc = task_alloc_security(tsk);
3196         if (rc)
3197                 return rc;
3198         tsec2 = tsk->security;
3199
3200         tsec2->osid = tsec1->osid;
3201         tsec2->sid = tsec1->sid;
3202
3203         /* Retain the exec, fs, key, and sock SIDs across fork */
3204         tsec2->exec_sid = tsec1->exec_sid;
3205         tsec2->create_sid = tsec1->create_sid;
3206         tsec2->keycreate_sid = tsec1->keycreate_sid;
3207         tsec2->sockcreate_sid = tsec1->sockcreate_sid;
3208
3209         return 0;
3210 }
3211
3212 static void selinux_task_free_security(struct task_struct *tsk)
3213 {
3214         task_free_security(tsk);
3215 }
3216
3217 static int selinux_task_setuid(uid_t id0, uid_t id1, uid_t id2, int flags)
3218 {
3219         /* Since setuid only affects the current process, and
3220            since the SELinux controls are not based on the Linux
3221            identity attributes, SELinux does not need to control
3222            this operation.  However, SELinux does control the use
3223            of the CAP_SETUID and CAP_SETGID capabilities using the
3224            capable hook. */
3225         return 0;
3226 }
3227
3228 static int selinux_task_post_setuid(uid_t id0, uid_t id1, uid_t id2, int flags)
3229 {
3230         return secondary_ops->task_post_setuid(id0, id1, id2, flags);
3231 }
3232
3233 static int selinux_task_setgid(gid_t id0, gid_t id1, gid_t id2, int flags)
3234 {
3235         /* See the comment for setuid above. */
3236         return 0;
3237 }
3238
3239 static int selinux_task_setpgid(struct task_struct *p, pid_t pgid)
3240 {
3241         return task_has_perm(current, p, PROCESS__SETPGID);
3242 }
3243
3244 static int selinux_task_getpgid(struct task_struct *p)
3245 {
3246         return task_has_perm(current, p, PROCESS__GETPGID);
3247 }
3248
3249 static int selinux_task_getsid(struct task_struct *p)
3250 {
3251         return task_has_perm(current, p, PROCESS__GETSESSION);
3252 }
3253
3254 static void selinux_task_getsecid(struct task_struct *p, u32 *secid)
3255 {
3256         struct task_security_struct *tsec = p->security;
3257         *secid = tsec->sid;
3258 }
3259
3260 static int selinux_task_setgroups(struct group_info *group_info)
3261 {
3262         /* See the comment for setuid above. */
3263         return 0;
3264 }
3265
3266 static int selinux_task_setnice(struct task_struct *p, int nice)
3267 {
3268         int rc;
3269
3270         rc = secondary_ops->task_setnice(p, nice);
3271         if (rc)
3272                 return rc;
3273
3274         return task_has_perm(current, p, PROCESS__SETSCHED);
3275 }
3276
3277 static int selinux_task_setioprio(struct task_struct *p, int ioprio)
3278 {
3279         int rc;
3280
3281         rc = secondary_ops->task_setioprio(p, ioprio);
3282         if (rc)
3283                 return rc;
3284
3285         return task_has_perm(current, p, PROCESS__SETSCHED);
3286 }
3287
3288 static int selinux_task_getioprio(struct task_struct *p)
3289 {
3290         return task_has_perm(current, p, PROCESS__GETSCHED);
3291 }
3292
3293 static int selinux_task_setrlimit(unsigned int resource, struct rlimit *new_rlim)
3294 {
3295         struct rlimit *old_rlim = current->signal->rlim + resource;
3296         int rc;
3297
3298         rc = secondary_ops->task_setrlimit(resource, new_rlim);
3299         if (rc)
3300                 return rc;
3301
3302         /* Control the ability to change the hard limit (whether
3303            lowering or raising it), so that the hard limit can
3304            later be used as a safe reset point for the soft limit
3305            upon context transitions. See selinux_bprm_apply_creds. */
3306         if (old_rlim->rlim_max != new_rlim->rlim_max)
3307                 return task_has_perm(current, current, PROCESS__SETRLIMIT);
3308
3309         return 0;
3310 }
3311
3312 static int selinux_task_setscheduler(struct task_struct *p, int policy, struct sched_param *lp)
3313 {
3314         int rc;
3315
3316         rc = secondary_ops->task_setscheduler(p, policy, lp);
3317         if (rc)
3318                 return rc;
3319
3320         return task_has_perm(current, p, PROCESS__SETSCHED);
3321 }
3322
3323 static int selinux_task_getscheduler(struct task_struct *p)
3324 {
3325         return task_has_perm(current, p, PROCESS__GETSCHED);
3326 }
3327
3328 static int selinux_task_movememory(struct task_struct *p)
3329 {
3330         return task_has_perm(current, p, PROCESS__SETSCHED);
3331 }
3332
3333 static int selinux_task_kill(struct task_struct *p, struct siginfo *info,
3334                                 int sig, u32 secid)
3335 {
3336         u32 perm;
3337         int rc;
3338         struct task_security_struct *tsec;
3339
3340         rc = secondary_ops->task_kill(p, info, sig, secid);
3341         if (rc)
3342                 return rc;
3343
3344         if (!sig)
3345                 perm = PROCESS__SIGNULL; /* null signal; existence test */
3346         else
3347                 perm = signal_to_av(sig);
3348         tsec = p->security;
3349         if (secid)
3350                 rc = avc_has_perm(secid, tsec->sid, SECCLASS_PROCESS, perm, NULL);
3351         else
3352                 rc = task_has_perm(current, p, perm);
3353         return rc;
3354 }
3355
3356 static int selinux_task_prctl(int option,
3357                               unsigned long arg2,
3358                               unsigned long arg3,
3359                               unsigned long arg4,
3360                               unsigned long arg5,
3361                               long *rc_p)
3362 {
3363         /* The current prctl operations do not appear to require
3364            any SELinux controls since they merely observe or modify
3365            the state of the current process. */
3366         return secondary_ops->task_prctl(option, arg2, arg3, arg4, arg5, rc_p);
3367 }
3368
3369 static int selinux_task_wait(struct task_struct *p)
3370 {
3371         return task_has_perm(p, current, PROCESS__SIGCHLD);
3372 }
3373
3374 static void selinux_task_reparent_to_init(struct task_struct *p)
3375 {
3376         struct task_security_struct *tsec;
3377
3378         secondary_ops->task_reparent_to_init(p);
3379
3380         tsec = p->security;
3381         tsec->osid = tsec->sid;
3382         tsec->sid = SECINITSID_KERNEL;
3383         return;
3384 }
3385
3386 static void selinux_task_to_inode(struct task_struct *p,
3387                                   struct inode *inode)
3388 {
3389         struct task_security_struct *tsec = p->security;
3390         struct inode_security_struct *isec = inode->i_security;
3391
3392         isec->sid = tsec->sid;
3393         isec->initialized = 1;
3394         return;
3395 }
3396
3397 /* Returns error only if unable to parse addresses */
3398 static int selinux_parse_skb_ipv4(struct sk_buff *skb,
3399                         struct avc_audit_data *ad, u8 *proto)
3400 {
3401         int offset, ihlen, ret = -EINVAL;
3402         struct iphdr _iph, *ih;
3403
3404         offset = skb_network_offset(skb);
3405         ih = skb_header_pointer(skb, offset, sizeof(_iph), &_iph);
3406         if (ih == NULL)
3407                 goto out;
3408
3409         ihlen = ih->ihl * 4;
3410         if (ihlen < sizeof(_iph))
3411                 goto out;
3412
3413         ad->u.net.v4info.saddr = ih->saddr;
3414         ad->u.net.v4info.daddr = ih->daddr;
3415         ret = 0;
3416
3417         if (proto)
3418                 *proto = ih->protocol;
3419
3420         switch (ih->protocol) {
3421         case IPPROTO_TCP: {
3422                 struct tcphdr _tcph, *th;
3423
3424                 if (ntohs(ih->frag_off) & IP_OFFSET)
3425                         break;
3426
3427                 offset += ihlen;
3428                 th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph);
3429                 if (th == NULL)
3430                         break;
3431
3432                 ad->u.net.sport = th->source;
3433                 ad->u.net.dport = th->dest;
3434                 break;
3435         }
3436
3437         case IPPROTO_UDP: {
3438                 struct udphdr _udph, *uh;
3439
3440                 if (ntohs(ih->frag_off) & IP_OFFSET)
3441                         break;
3442
3443                 offset += ihlen;
3444                 uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph);
3445                 if (uh == NULL)
3446                         break;
3447
3448                 ad->u.net.sport = uh->source;
3449                 ad->u.net.dport = uh->dest;
3450                 break;
3451         }
3452
3453         case IPPROTO_DCCP: {
3454                 struct dccp_hdr _dccph, *dh;
3455
3456                 if (ntohs(ih->frag_off) & IP_OFFSET)
3457                         break;
3458
3459                 offset += ihlen;
3460                 dh = skb_header_pointer(skb, offset, sizeof(_dccph), &_dccph);
3461                 if (dh == NULL)
3462                         break;
3463
3464                 ad->u.net.sport = dh->dccph_sport;
3465                 ad->u.net.dport = dh->dccph_dport;
3466                 break;
3467         }
3468
3469         default:
3470                 break;
3471         }
3472 out:
3473         return ret;
3474 }
3475
3476 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
3477
3478 /* Returns error only if unable to parse addresses */
3479 static int selinux_parse_skb_ipv6(struct sk_buff *skb,
3480                         struct avc_audit_data *ad, u8 *proto)
3481 {
3482         u8 nexthdr;
3483         int ret = -EINVAL, offset;
3484         struct ipv6hdr _ipv6h, *ip6;
3485
3486         offset = skb_network_offset(skb);
3487         ip6 = skb_header_pointer(skb, offset, sizeof(_ipv6h), &_ipv6h);
3488         if (ip6 == NULL)
3489                 goto out;
3490
3491         ipv6_addr_copy(&ad->u.net.v6info.saddr, &ip6->saddr);
3492         ipv6_addr_copy(&ad->u.net.v6info.daddr, &ip6->daddr);
3493         ret = 0;
3494
3495         nexthdr = ip6->nexthdr;
3496         offset += sizeof(_ipv6h);
3497         offset = ipv6_skip_exthdr(skb, offset, &nexthdr);
3498         if (offset < 0)
3499                 goto out;
3500
3501         if (proto)
3502                 *proto = nexthdr;
3503
3504         switch (nexthdr) {
3505         case IPPROTO_TCP: {
3506                 struct tcphdr _tcph, *th;
3507
3508                 th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph);
3509                 if (th == NULL)
3510                         break;
3511
3512                 ad->u.net.sport = th->source;
3513                 ad->u.net.dport = th->dest;
3514                 break;
3515         }
3516
3517         case IPPROTO_UDP: {
3518                 struct udphdr _udph, *uh;
3519
3520                 uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph);
3521                 if (uh == NULL)
3522                         break;
3523
3524                 ad->u.net.sport = uh->source;
3525                 ad->u.net.dport = uh->dest;
3526                 break;
3527         }
3528
3529         case IPPROTO_DCCP: {
3530                 struct dccp_hdr _dccph, *dh;
3531
3532                 dh = skb_header_pointer(skb, offset, sizeof(_dccph), &_dccph);
3533                 if (dh == NULL)
3534                         break;
3535
3536                 ad->u.net.sport = dh->dccph_sport;
3537                 ad->u.net.dport = dh->dccph_dport;
3538                 break;
3539         }
3540
3541         /* includes fragments */
3542         default:
3543                 break;
3544         }
3545 out:
3546         return ret;
3547 }
3548
3549 #endif /* IPV6 */
3550
3551 static int selinux_parse_skb(struct sk_buff *skb, struct avc_audit_data *ad,
3552                              char **_addrp, int src, u8 *proto)
3553 {
3554         char *addrp;
3555         int ret;
3556
3557         switch (ad->u.net.family) {
3558         case PF_INET:
3559                 ret = selinux_parse_skb_ipv4(skb, ad, proto);
3560                 if (ret)
3561                         goto parse_error;
3562                 addrp = (char *)(src ? &ad->u.net.v4info.saddr :
3563                                        &ad->u.net.v4info.daddr);
3564                 goto okay;
3565
3566 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
3567         case PF_INET6:
3568                 ret = selinux_parse_skb_ipv6(skb, ad, proto);
3569                 if (ret)
3570                         goto parse_error;
3571                 addrp = (char *)(src ? &ad->u.net.v6info.saddr :
3572                                        &ad->u.net.v6info.daddr);
3573                 goto okay;
3574 #endif  /* IPV6 */
3575         default:
3576                 addrp = NULL;
3577                 goto okay;
3578         }
3579
3580 parse_error:
3581         printk(KERN_WARNING
3582                "SELinux: failure in selinux_parse_skb(),"
3583                " unable to parse packet\n");
3584         return ret;
3585
3586 okay:
3587         if (_addrp)
3588                 *_addrp = addrp;
3589         return 0;
3590 }
3591
3592 /**
3593  * selinux_skb_peerlbl_sid - Determine the peer label of a packet
3594  * @skb: the packet
3595  * @family: protocol family
3596  * @sid: the packet's peer label SID
3597  *
3598  * Description:
3599  * Check the various different forms of network peer labeling and determine
3600  * the peer label/SID for the packet; most of the magic actually occurs in
3601  * the security server function security_net_peersid_cmp().  The function
3602  * returns zero if the value in @sid is valid (although it may be SECSID_NULL)
3603  * or -EACCES if @sid is invalid due to inconsistencies with the different
3604  * peer labels.
3605  *
3606  */
3607 static int selinux_skb_peerlbl_sid(struct sk_buff *skb, u16 family, u32 *sid)
3608 {
3609         int err;
3610         u32 xfrm_sid;
3611         u32 nlbl_sid;
3612         u32 nlbl_type;
3613
3614         selinux_skb_xfrm_sid(skb, &xfrm_sid);
3615         selinux_netlbl_skbuff_getsid(skb, family, &nlbl_type, &nlbl_sid);
3616
3617         err = security_net_peersid_resolve(nlbl_sid, nlbl_type, xfrm_sid, sid);
3618         if (unlikely(err)) {
3619                 printk(KERN_WARNING
3620                        "SELinux: failure in selinux_skb_peerlbl_sid(),"
3621                        " unable to determine packet's peer label\n");
3622                 return -EACCES;
3623         }
3624
3625         return 0;
3626 }
3627
3628 /* socket security operations */
3629 static int socket_has_perm(struct task_struct *task, struct socket *sock,
3630                            u32 perms)
3631 {
3632         struct inode_security_struct *isec;
3633         struct task_security_struct *tsec;
3634         struct avc_audit_data ad;
3635         int err = 0;
3636
3637         tsec = task->security;
3638         isec = SOCK_INODE(sock)->i_security;
3639
3640         if (isec->sid == SECINITSID_KERNEL)
3641                 goto out;
3642
3643         AVC_AUDIT_DATA_INIT(&ad, NET);
3644         ad.u.net.sk = sock->sk;
3645         err = avc_has_perm(tsec->sid, isec->sid, isec->sclass, perms, &ad);
3646
3647 out:
3648         return err;
3649 }
3650
3651 static int selinux_socket_create(int family, int type,
3652                                  int protocol, int kern)
3653 {
3654         int err = 0;
3655         struct task_security_struct *tsec;
3656         u32 newsid;
3657
3658         if (kern)
3659                 goto out;
3660
3661         tsec = current->security;
3662         newsid = tsec->sockcreate_sid ? : tsec->sid;
3663         err = avc_has_perm(tsec->sid, newsid,
3664                            socket_type_to_security_class(family, type,
3665                            protocol), SOCKET__CREATE, NULL);
3666
3667 out:
3668         return err;
3669 }
3670
3671 static int selinux_socket_post_create(struct socket *sock, int family,
3672                                       int type, int protocol, int kern)
3673 {
3674         int err = 0;
3675         struct inode_security_struct *isec;
3676         struct task_security_struct *tsec;
3677         struct sk_security_struct *sksec;
3678         u32 newsid;
3679
3680         isec = SOCK_INODE(sock)->i_security;
3681
3682         tsec = current->security;
3683         newsid = tsec->sockcreate_sid ? : tsec->sid;
3684         isec->sclass = socket_type_to_security_class(family, type, protocol);
3685         isec->sid = kern ? SECINITSID_KERNEL : newsid;
3686         isec->initialized = 1;
3687
3688         if (sock->sk) {
3689                 sksec = sock->sk->sk_security;
3690                 sksec->sid = isec->sid;
3691                 sksec->sclass = isec->sclass;
3692                 err = selinux_netlbl_socket_post_create(sock);
3693         }
3694
3695         return err;
3696 }
3697
3698 /* Range of port numbers used to automatically bind.
3699    Need to determine whether we should perform a name_bind
3700    permission check between the socket and the port number. */
3701
3702 static int selinux_socket_bind(struct socket *sock, struct sockaddr *address, int addrlen)
3703 {
3704         u16 family;
3705         int err;
3706
3707         err = socket_has_perm(current, sock, SOCKET__BIND);
3708         if (err)
3709                 goto out;
3710
3711         /*
3712          * If PF_INET or PF_INET6, check name_bind permission for the port.
3713          * Multiple address binding for SCTP is not supported yet: we just
3714          * check the first address now.
3715          */
3716         family = sock->sk->sk_family;
3717         if (family == PF_INET || family == PF_INET6) {
3718                 char *addrp;
3719                 struct inode_security_struct *isec;
3720                 struct task_security_struct *tsec;
3721                 struct avc_audit_data ad;
3722                 struct sockaddr_in *addr4 = NULL;
3723                 struct sockaddr_in6 *addr6 = NULL;
3724                 unsigned short snum;
3725                 struct sock *sk = sock->sk;
3726                 u32 sid, node_perm;
3727
3728                 tsec = current->security;
3729                 isec = SOCK_INODE(sock)->i_security;
3730
3731                 if (family == PF_INET) {
3732                         addr4 = (struct sockaddr_in *)address;
3733                         snum = ntohs(addr4->sin_port);
3734                         addrp = (char *)&addr4->sin_addr.s_addr;
3735                 } else {
3736                         addr6 = (struct sockaddr_in6 *)address;
3737                         snum = ntohs(addr6->sin6_port);
3738                         addrp = (char *)&addr6->sin6_addr.s6_addr;
3739                 }
3740
3741                 if (snum) {
3742                         int low, high;
3743
3744                         inet_get_local_port_range(&low, &high);
3745
3746                         if (snum < max(PROT_SOCK, low) || snum > high) {
3747                                 err = sel_netport_sid(sk->sk_protocol,
3748                                                       snum, &sid);
3749                                 if (err)
3750                                         goto out;
3751                                 AVC_AUDIT_DATA_INIT(&ad, NET);
3752                                 ad.u.net.sport = htons(snum);
3753                                 ad.u.net.family = family;
3754                                 err = avc_has_perm(isec->sid, sid,
3755                                                    isec->sclass,
3756                                                    SOCKET__NAME_BIND, &ad);
3757                                 if (err)
3758                                         goto out;
3759                         }
3760                 }
3761
3762                 switch (isec->sclass) {
3763                 case SECCLASS_TCP_SOCKET:
3764                         node_perm = TCP_SOCKET__NODE_BIND;
3765                         break;
3766
3767                 case SECCLASS_UDP_SOCKET:
3768                         node_perm = UDP_SOCKET__NODE_BIND;
3769                         break;
3770
3771                 case SECCLASS_DCCP_SOCKET:
3772                         node_perm = DCCP_SOCKET__NODE_BIND;
3773                         break;
3774
3775                 default:
3776                         node_perm = RAWIP_SOCKET__NODE_BIND;
3777                         break;
3778                 }
3779
3780                 err = sel_netnode_sid(addrp, family, &sid);
3781                 if (err)
3782                         goto out;
3783
3784                 AVC_AUDIT_DATA_INIT(&ad, NET);
3785                 ad.u.net.sport = htons(snum);
3786                 ad.u.net.family = family;
3787
3788                 if (family == PF_INET)
3789                         ad.u.net.v4info.saddr = addr4->sin_addr.s_addr;
3790                 else
3791                         ipv6_addr_copy(&ad.u.net.v6info.saddr, &addr6->sin6_addr);
3792
3793                 err = avc_has_perm(isec->sid, sid,
3794                                    isec->sclass, node_perm, &ad);
3795                 if (err)
3796                         goto out;
3797         }
3798 out:
3799         return err;
3800 }
3801
3802 static int selinux_socket_connect(struct socket *sock, struct sockaddr *address, int addrlen)
3803 {
3804         struct inode_security_struct *isec;
3805         int err;
3806
3807         err = socket_has_perm(current, sock, SOCKET__CONNECT);
3808         if (err)
3809                 return err;
3810
3811         /*
3812          * If a TCP or DCCP socket, check name_connect permission for the port.
3813          */
3814         isec = SOCK_INODE(sock)->i_security;
3815         if (isec->sclass == SECCLASS_TCP_SOCKET ||
3816             isec->sclass == SECCLASS_DCCP_SOCKET) {
3817                 struct sock *sk = sock->sk;
3818                 struct avc_audit_data ad;
3819                 struct sockaddr_in *addr4 = NULL;
3820                 struct sockaddr_in6 *addr6 = NULL;
3821                 unsigned short snum;
3822                 u32 sid, perm;
3823
3824                 if (sk->sk_family == PF_INET) {
3825                         addr4 = (struct sockaddr_in *)address;
3826                         if (addrlen < sizeof(struct sockaddr_in))
3827                                 return -EINVAL;
3828                         snum = ntohs(addr4->sin_port);
3829                 } else {
3830                         addr6 = (struct sockaddr_in6 *)address;
3831                         if (addrlen < SIN6_LEN_RFC2133)
3832                                 return -EINVAL;
3833                         snum = ntohs(addr6->sin6_port);
3834                 }
3835
3836                 err = sel_netport_sid(sk->sk_protocol, snum, &sid);
3837                 if (err)
3838                         goto out;
3839
3840                 perm = (isec->sclass == SECCLASS_TCP_SOCKET) ?
3841                        TCP_SOCKET__NAME_CONNECT : DCCP_SOCKET__NAME_CONNECT;
3842
3843                 AVC_AUDIT_DATA_INIT(&ad, NET);
3844                 ad.u.net.dport = htons(snum);
3845                 ad.u.net.family = sk->sk_family;
3846                 err = avc_has_perm(isec->sid, sid, isec->sclass, perm, &ad);
3847                 if (err)
3848                         goto out;
3849         }
3850
3851 out:
3852         return err;
3853 }
3854
3855 static int selinux_socket_listen(struct socket *sock, int backlog)
3856 {
3857         return socket_has_perm(current, sock, SOCKET__LISTEN);
3858 }
3859
3860 static int selinux_socket_accept(struct socket *sock, struct socket *newsock)
3861 {
3862         int err;
3863         struct inode_security_struct *isec;
3864         struct inode_security_struct *newisec;
3865
3866         err = socket_has_perm(current, sock, SOCKET__ACCEPT);
3867         if (err)
3868                 return err;
3869
3870         newisec = SOCK_INODE(newsock)->i_security;
3871
3872         isec = SOCK_INODE(sock)->i_security;
3873         newisec->sclass = isec->sclass;
3874         newisec->sid = isec->sid;
3875         newisec->initialized = 1;
3876
3877         return 0;
3878 }
3879
3880 static int selinux_socket_sendmsg(struct socket *sock, struct msghdr *msg,
3881                                   int size)
3882 {
3883         int rc;
3884
3885         rc = socket_has_perm(current, sock, SOCKET__WRITE);
3886         if (rc)
3887                 return rc;
3888
3889         return selinux_netlbl_inode_permission(SOCK_INODE(sock), MAY_WRITE);
3890 }
3891
3892 static int selinux_socket_recvmsg(struct socket *sock, struct msghdr *msg,
3893                                   int size, int flags)
3894 {
3895         return socket_has_perm(current, sock, SOCKET__READ);
3896 }
3897
3898 static int selinux_socket_getsockname(struct socket *sock)
3899 {
3900         return socket_has_perm(current, sock, SOCKET__GETATTR);
3901 }
3902
3903 static int selinux_socket_getpeername(struct socket *sock)
3904 {
3905         return socket_has_perm(current, sock, SOCKET__GETATTR);
3906 }
3907
3908 static int selinux_socket_setsockopt(struct socket *sock, int level, int optname)
3909 {
3910         int err;
3911
3912         err = socket_has_perm(current, sock, SOCKET__SETOPT);
3913         if (err)
3914                 return err;
3915
3916         return selinux_netlbl_socket_setsockopt(sock, level, optname);
3917 }
3918
3919 static int selinux_socket_getsockopt(struct socket *sock, int level,
3920                                      int optname)
3921 {
3922         return socket_has_perm(current, sock, SOCKET__GETOPT);
3923 }
3924
3925 static int selinux_socket_shutdown(struct socket *sock, int how)
3926 {
3927         return socket_has_perm(current, sock, SOCKET__SHUTDOWN);
3928 }
3929
3930 static int selinux_socket_unix_stream_connect(struct socket *sock,
3931                                               struct socket *other,
3932                                               struct sock *newsk)
3933 {
3934         struct sk_security_struct *ssec;
3935         struct inode_security_struct *isec;
3936         struct inode_security_struct *other_isec;
3937         struct avc_audit_data ad;
3938         int err;
3939
3940         err = secondary_ops->unix_stream_connect(sock, other, newsk);
3941         if (err)
3942                 return err;
3943
3944         isec = SOCK_INODE(sock)->i_security;
3945         other_isec = SOCK_INODE(other)->i_security;
3946
3947         AVC_AUDIT_DATA_INIT(&ad, NET);
3948         ad.u.net.sk = other->sk;
3949
3950         err = avc_has_perm(isec->sid, other_isec->sid,
3951                            isec->sclass,
3952                            UNIX_STREAM_SOCKET__CONNECTTO, &ad);
3953         if (err)
3954                 return err;
3955
3956         /* connecting socket */
3957         ssec = sock->sk->sk_security;
3958         ssec->peer_sid = other_isec->sid;
3959
3960         /* server child socket */
3961         ssec = newsk->sk_security;
3962         ssec->peer_sid = isec->sid;
3963         err = security_sid_mls_copy(other_isec->sid, ssec->peer_sid, &ssec->sid);
3964
3965         return err;
3966 }
3967
3968 static int selinux_socket_unix_may_send(struct socket *sock,
3969                                         struct socket *other)
3970 {
3971         struct inode_security_struct *isec;
3972         struct inode_security_struct *other_isec;
3973         struct avc_audit_data ad;
3974         int err;
3975
3976         isec = SOCK_INODE(sock)->i_security;
3977         other_isec = SOCK_INODE(other)->i_security;
3978
3979         AVC_AUDIT_DATA_INIT(&ad, NET);
3980         ad.u.net.sk = other->sk;
3981
3982         err = avc_has_perm(isec->sid, other_isec->sid,
3983                            isec->sclass, SOCKET__SENDTO, &ad);
3984         if (err)
3985                 return err;
3986
3987         return 0;
3988 }
3989
3990 static int selinux_inet_sys_rcv_skb(int ifindex, char *addrp, u16 family,
3991                                     u32 peer_sid,
3992                                     struct avc_audit_data *ad)
3993 {
3994         int err;
3995         u32 if_sid;
3996         u32 node_sid;
3997
3998         err = sel_netif_sid(ifindex, &if_sid);
3999         if (err)
4000                 return err;
4001         err = avc_has_perm(peer_sid, if_sid,
4002                            SECCLASS_NETIF, NETIF__INGRESS, ad);
4003         if (err)
4004                 return err;
4005
4006         err = sel_netnode_sid(addrp, family, &node_sid);
4007         if (err)
4008                 return err;
4009         return avc_has_perm(peer_sid, node_sid,
4010                             SECCLASS_NODE, NODE__RECVFROM, ad);
4011 }
4012
4013 static int selinux_sock_rcv_skb_iptables_compat(struct sock *sk,
4014                                                 struct sk_buff *skb,
4015                                                 struct avc_audit_data *ad,
4016                                                 u16 family,
4017                                                 char *addrp)
4018 {
4019         int err;
4020         struct sk_security_struct *sksec = sk->sk_security;
4021         u16 sk_class;
4022         u32 netif_perm, node_perm, recv_perm;
4023         u32 port_sid, node_sid, if_sid, sk_sid;
4024
4025         sk_sid = sksec->sid;
4026         sk_class = sksec->sclass;
4027
4028         switch (sk_class) {
4029         case SECCLASS_UDP_SOCKET:
4030                 netif_perm = NETIF__UDP_RECV;
4031                 node_perm = NODE__UDP_RECV;
4032                 recv_perm = UDP_SOCKET__RECV_MSG;
4033                 break;
4034         case SECCLASS_TCP_SOCKET:
4035                 netif_perm = NETIF__TCP_RECV;
4036                 node_perm = NODE__TCP_RECV;
4037                 recv_perm = TCP_SOCKET__RECV_MSG;
4038                 break;
4039         case SECCLASS_DCCP_SOCKET:
4040                 netif_perm = NETIF__DCCP_RECV;
4041                 node_perm = NODE__DCCP_RECV;
4042                 recv_perm = DCCP_SOCKET__RECV_MSG;
4043                 break;
4044         default:
4045                 netif_perm = NETIF__RAWIP_RECV;
4046                 node_perm = NODE__RAWIP_RECV;
4047                 recv_perm = 0;
4048                 break;
4049         }
4050
4051         err = sel_netif_sid(skb->iif, &if_sid);
4052         if (err)
4053                 return err;
4054         err = avc_has_perm(sk_sid, if_sid, SECCLASS_NETIF, netif_perm, ad);
4055         if (err)
4056                 return err;
4057
4058         err = sel_netnode_sid(addrp, family, &node_sid);
4059         if (err)
4060                 return err;
4061         err = avc_has_perm(sk_sid, node_sid, SECCLASS_NODE, node_perm, ad);
4062         if (err)
4063                 return err;
4064
4065         if (!recv_perm)
4066                 return 0;
4067         err = sel_netport_sid(sk->sk_protocol,
4068                               ntohs(ad->u.net.sport), &port_sid);
4069         if (unlikely(err)) {
4070                 printk(KERN_WARNING
4071                        "SELinux: failure in"
4072                        " selinux_sock_rcv_skb_iptables_compat(),"
4073                        " network port label not found\n");
4074                 return err;
4075         }
4076         return avc_has_perm(sk_sid, port_sid, sk_class, recv_perm, ad);
4077 }
4078
4079 static int selinux_sock_rcv_skb_compat(struct sock *sk, struct sk_buff *skb,
4080                                        struct avc_audit_data *ad,
4081                                        u16 family, char *addrp)
4082 {
4083         int err;
4084         struct sk_security_struct *sksec = sk->sk_security;
4085         u32 peer_sid;
4086         u32 sk_sid = sksec->sid;
4087
4088         if (selinux_compat_net)
4089                 err = selinux_sock_rcv_skb_iptables_compat(sk, skb, ad,
4090                                                            family, addrp);
4091         else
4092                 err = avc_has_perm(sk_sid, skb->secmark, SECCLASS_PACKET,
4093                                    PACKET__RECV, ad);
4094         if (err)
4095                 return err;
4096
4097         if (selinux_policycap_netpeer) {
4098                 err = selinux_skb_peerlbl_sid(skb, family, &peer_sid);
4099                 if (err)
4100                         return err;
4101                 err = avc_has_perm(sk_sid, peer_sid,
4102                                    SECCLASS_PEER, PEER__RECV, ad);
4103         } else {
4104                 err = selinux_netlbl_sock_rcv_skb(sksec, skb, family, ad);
4105                 if (err)
4106                         return err;
4107                 err = selinux_xfrm_sock_rcv_skb(sksec->sid, skb, ad);
4108         }
4109
4110         return err;
4111 }
4112
4113 static int selinux_socket_sock_rcv_skb(struct sock *sk, struct sk_buff *skb)
4114 {
4115         int err;
4116         struct sk_security_struct *sksec = sk->sk_security;
4117         u16 family = sk->sk_family;
4118         u32 sk_sid = sksec->sid;
4119         struct avc_audit_data ad;
4120         char *addrp;
4121
4122         if (family != PF_INET && family != PF_INET6)
4123                 return 0;
4124
4125         /* Handle mapped IPv4 packets arriving via IPv6 sockets */
4126         if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
4127                 family = PF_INET;
4128
4129         AVC_AUDIT_DATA_INIT(&ad, NET);
4130         ad.u.net.netif = skb->iif;
4131         ad.u.net.family = family;
4132         err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL);
4133         if (err)
4134                 return err;
4135
4136         /* If any sort of compatibility mode is enabled then handoff processing
4137          * to the selinux_sock_rcv_skb_compat() function to deal with the
4138          * special handling.  We do this in an attempt to keep this function
4139          * as fast and as clean as possible. */
4140         if (selinux_compat_net || !selinux_policycap_netpeer)
4141                 return selinux_sock_rcv_skb_compat(sk, skb, &ad,
4142                                                    family, addrp);
4143
4144         if (netlbl_enabled() || selinux_xfrm_enabled()) {
4145                 u32 peer_sid;
4146
4147                 err = selinux_skb_peerlbl_sid(skb, family, &peer_sid);
4148                 if (err)
4149                         return err;
4150                 err = selinux_inet_sys_rcv_skb(skb->iif, addrp, family,
4151                                                peer_sid, &ad);
4152                 if (err)
4153                         return err;
4154                 err = avc_has_perm(sk_sid, peer_sid, SECCLASS_PEER,
4155                                    PEER__RECV, &ad);
4156         }
4157
4158         if (selinux_secmark_enabled()) {
4159                 err = avc_has_perm(sk_sid, skb->secmark, SECCLASS_PACKET,
4160                                    PACKET__RECV, &ad);
4161                 if (err)
4162                         return err;
4163         }
4164
4165         return err;
4166 }
4167
4168 static int selinux_socket_getpeersec_stream(struct socket *sock, char __user *optval,
4169                                             int __user *optlen, unsigned len)
4170 {
4171         int err = 0;
4172         char *scontext;
4173         u32 scontext_len;
4174         struct sk_security_struct *ssec;
4175         struct inode_security_struct *isec;
4176         u32 peer_sid = SECSID_NULL;
4177
4178         isec = SOCK_INODE(sock)->i_security;
4179
4180         if (isec->sclass == SECCLASS_UNIX_STREAM_SOCKET ||
4181             isec->sclass == SECCLASS_TCP_SOCKET) {
4182                 ssec = sock->sk->sk_security;
4183                 peer_sid = ssec->peer_sid;
4184         }
4185         if (peer_sid == SECSID_NULL) {
4186                 err = -ENOPROTOOPT;
4187                 goto out;
4188         }
4189
4190         err = security_sid_to_context(peer_sid, &scontext, &scontext_len);
4191
4192         if (err)
4193                 goto out;
4194
4195         if (scontext_len > len) {
4196                 err = -ERANGE;
4197                 goto out_len;
4198         }
4199
4200         if (copy_to_user(optval, scontext, scontext_len))
4201                 err = -EFAULT;
4202
4203 out_len:
4204         if (put_user(scontext_len, optlen))
4205                 err = -EFAULT;
4206
4207         kfree(scontext);
4208 out:
4209         return err;
4210 }
4211
4212 static int selinux_socket_getpeersec_dgram(struct socket *sock, struct sk_buff *skb, u32 *secid)
4213 {
4214         u32 peer_secid = SECSID_NULL;
4215         u16 family;
4216
4217         if (sock)
4218                 family = sock->sk->sk_family;
4219         else if (skb && skb->sk)
4220                 family = skb->sk->sk_family;
4221         else
4222                 goto out;
4223
4224         if (sock && family == PF_UNIX)
4225                 selinux_inode_getsecid(SOCK_INODE(sock), &peer_secid);
4226         else if (skb)
4227                 selinux_skb_peerlbl_sid(skb, family, &peer_secid);
4228
4229 out:
4230         *secid = peer_secid;
4231         if (peer_secid == SECSID_NULL)
4232                 return -EINVAL;
4233         return 0;
4234 }
4235
4236 static int selinux_sk_alloc_security(struct sock *sk, int family, gfp_t priority)
4237 {
4238         return sk_alloc_security(sk, family, priority);
4239 }
4240
4241 static void selinux_sk_free_security(struct sock *sk)
4242 {
4243         sk_free_security(sk);
4244 }
4245
4246 static void selinux_sk_clone_security(const struct sock *sk, struct sock *newsk)
4247 {
4248         struct sk_security_struct *ssec = sk->sk_security;
4249         struct sk_security_struct *newssec = newsk->sk_security;
4250
4251         newssec->sid = ssec->sid;
4252         newssec->peer_sid = ssec->peer_sid;
4253         newssec->sclass = ssec->sclass;
4254
4255         selinux_netlbl_sk_security_reset(newssec, newsk->sk_family);
4256 }
4257
4258 static void selinux_sk_getsecid(struct sock *sk, u32 *secid)
4259 {
4260         if (!sk)
4261                 *secid = SECINITSID_ANY_SOCKET;
4262         else {
4263                 struct sk_security_struct *sksec = sk->sk_security;
4264
4265                 *secid = sksec->sid;
4266         }
4267 }
4268
4269 static void selinux_sock_graft(struct sock *sk, struct socket *parent)
4270 {
4271         struct inode_security_struct *isec = SOCK_INODE(parent)->i_security;
4272         struct sk_security_struct *sksec = sk->sk_security;
4273
4274         if (sk->sk_family == PF_INET || sk->sk_family == PF_INET6 ||
4275             sk->sk_family == PF_UNIX)
4276                 isec->sid = sksec->sid;
4277         sksec->sclass = isec->sclass;
4278
4279         selinux_netlbl_sock_graft(sk, parent);
4280 }
4281
4282 static int selinux_inet_conn_request(struct sock *sk, struct sk_buff *skb,
4283                                      struct request_sock *req)
4284 {
4285         struct sk_security_struct *sksec = sk->sk_security;
4286         int err;
4287         u32 newsid;
4288         u32 peersid;
4289
4290         err = selinux_skb_peerlbl_sid(skb, sk->sk_family, &peersid);
4291         if (err)
4292                 return err;
4293         if (peersid == SECSID_NULL) {
4294                 req->secid = sksec->sid;
4295                 req->peer_secid = SECSID_NULL;
4296                 return 0;
4297         }
4298
4299         err = security_sid_mls_copy(sksec->sid, peersid, &newsid);
4300         if (err)
4301                 return err;
4302
4303         req->secid = newsid;
4304         req->peer_secid = peersid;
4305         return 0;
4306 }
4307
4308 static void selinux_inet_csk_clone(struct sock *newsk,
4309                                    const struct request_sock *req)
4310 {
4311         struct sk_security_struct *newsksec = newsk->sk_security;
4312
4313         newsksec->sid = req->secid;
4314         newsksec->peer_sid = req->peer_secid;
4315         /* NOTE: Ideally, we should also get the isec->sid for the
4316            new socket in sync, but we don't have the isec available yet.
4317            So we will wait until sock_graft to do it, by which
4318            time it will have been created and available. */
4319
4320         /* We don't need to take any sort of lock here as we are the only
4321          * thread with access to newsksec */
4322         selinux_netlbl_sk_security_reset(newsksec, req->rsk_ops->family);
4323 }
4324
4325 static void selinux_inet_conn_established(struct sock *sk,
4326                                 struct sk_buff *skb)
4327 {
4328         struct sk_security_struct *sksec = sk->sk_security;
4329
4330         selinux_skb_peerlbl_sid(skb, sk->sk_family, &sksec->peer_sid);
4331 }
4332
4333 static void selinux_req_classify_flow(const struct request_sock *req,
4334                                       struct flowi *fl)
4335 {
4336         fl->secid = req->secid;
4337 }
4338
4339 static int selinux_nlmsg_perm(struct sock *sk, struct sk_buff *skb)
4340 {
4341         int err = 0;
4342         u32 perm;
4343         struct nlmsghdr *nlh;
4344         struct socket *sock = sk->sk_socket;
4345         struct inode_security_struct *isec = SOCK_INODE(sock)->i_security;
4346
4347         if (skb->len < NLMSG_SPACE(0)) {
4348                 err = -EINVAL;
4349                 goto out;
4350         }
4351         nlh = nlmsg_hdr(skb);
4352
4353         err = selinux_nlmsg_lookup(isec->sclass, nlh->nlmsg_type, &perm);
4354         if (err) {
4355                 if (err == -EINVAL) {
4356                         audit_log(current->audit_context, GFP_KERNEL, AUDIT_SELINUX_ERR,
4357                                   "SELinux:  unrecognized netlink message"
4358                                   " type=%hu for sclass=%hu\n",
4359                                   nlh->nlmsg_type, isec->sclass);
4360                         if (!selinux_enforcing)
4361                                 err = 0;
4362                 }
4363
4364                 /* Ignore */
4365                 if (err == -ENOENT)
4366                         err = 0;
4367                 goto out;
4368         }
4369
4370         err = socket_has_perm(current, sock, perm);
4371 out:
4372         return err;
4373 }
4374
4375 #ifdef CONFIG_NETFILTER
4376
4377 static unsigned int selinux_ip_forward(struct sk_buff *skb, int ifindex,
4378                                        u16 family)
4379 {
4380         char *addrp;
4381         u32 peer_sid;
4382         struct avc_audit_data ad;
4383         u8 secmark_active;
4384         u8 peerlbl_active;
4385
4386         if (!selinux_policycap_netpeer)
4387                 return NF_ACCEPT;
4388
4389         secmark_active = selinux_secmark_enabled();
4390         peerlbl_active = netlbl_enabled() || selinux_xfrm_enabled();
4391         if (!secmark_active && !peerlbl_active)
4392                 return NF_ACCEPT;
4393
4394         AVC_AUDIT_DATA_INIT(&ad, NET);
4395         ad.u.net.netif = ifindex;
4396         ad.u.net.family = family;
4397         if (selinux_parse_skb(skb, &ad, &addrp, 1, NULL) != 0)
4398                 return NF_DROP;
4399
4400         if (selinux_skb_peerlbl_sid(skb, family, &peer_sid) != 0)
4401                 return NF_DROP;
4402
4403         if (peerlbl_active)
4404                 if (selinux_inet_sys_rcv_skb(ifindex, addrp, family,
4405                                              peer_sid, &ad) != 0)
4406                         return NF_DROP;
4407
4408         if (secmark_active)
4409                 if (avc_has_perm(peer_sid, skb->secmark,
4410                                  SECCLASS_PACKET, PACKET__FORWARD_IN, &ad))
4411                         return NF_DROP;
4412
4413         return NF_ACCEPT;
4414 }
4415
4416 static unsigned int selinux_ipv4_forward(unsigned int hooknum,
4417                                          struct sk_buff *skb,
4418                                          const struct net_device *in,
4419                                          const struct net_device *out,
4420                                          int (*okfn)(struct sk_buff *))
4421 {
4422         return selinux_ip_forward(skb, in->ifindex, PF_INET);
4423 }
4424
4425 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
4426 static unsigned int selinux_ipv6_forward(unsigned int hooknum,
4427                                          struct sk_buff *skb,
4428                                          const struct net_device *in,
4429                                          const struct net_device *out,
4430                                          int (*okfn)(struct sk_buff *))
4431 {
4432         return selinux_ip_forward(skb, in->ifindex, PF_INET6);
4433 }
4434 #endif  /* IPV6 */
4435
4436 static int selinux_ip_postroute_iptables_compat(struct sock *sk,
4437                                                 int ifindex,
4438                                                 struct avc_audit_data *ad,
4439                                                 u16 family, char *addrp)
4440 {
4441         int err;
4442         struct sk_security_struct *sksec = sk->sk_security;
4443         u16 sk_class;
4444         u32 netif_perm, node_perm, send_perm;
4445         u32 port_sid, node_sid, if_sid, sk_sid;
4446
4447         sk_sid = sksec->sid;
4448         sk_class = sksec->sclass;
4449
4450         switch (sk_class) {
4451         case SECCLASS_UDP_SOCKET:
4452                 netif_perm = NETIF__UDP_SEND;
4453                 node_perm = NODE__UDP_SEND;
4454                 send_perm = UDP_SOCKET__SEND_MSG;
4455                 break;
4456         case SECCLASS_TCP_SOCKET:
4457                 netif_perm = NETIF__TCP_SEND;
4458                 node_perm = NODE__TCP_SEND;
4459                 send_perm = TCP_SOCKET__SEND_MSG;
4460                 break;
4461         case SECCLASS_DCCP_SOCKET:
4462                 netif_perm = NETIF__DCCP_SEND;
4463                 node_perm = NODE__DCCP_SEND;
4464                 send_perm = DCCP_SOCKET__SEND_MSG;
4465                 break;
4466         default:
4467                 netif_perm = NETIF__RAWIP_SEND;
4468                 node_perm = NODE__RAWIP_SEND;
4469                 send_perm = 0;
4470                 break;
4471         }
4472
4473         err = sel_netif_sid(ifindex, &if_sid);
4474         if (err)
4475                 return err;
4476         err = avc_has_perm(sk_sid, if_sid, SECCLASS_NETIF, netif_perm, ad);
4477                 return err;
4478
4479         err = sel_netnode_sid(addrp, family, &node_sid);
4480         if (err)
4481                 return err;
4482         err = avc_has_perm(sk_sid, node_sid, SECCLASS_NODE, node_perm, ad);
4483         if (err)
4484                 return err;
4485
4486         if (send_perm != 0)
4487                 return 0;
4488
4489         err = sel_netport_sid(sk->sk_protocol,
4490                               ntohs(ad->u.net.dport), &port_sid);
4491         if (unlikely(err)) {
4492                 printk(KERN_WARNING
4493                        "SELinux: failure in"
4494                        " selinux_ip_postroute_iptables_compat(),"
4495                        " network port label not found\n");
4496                 return err;
4497         }
4498         return avc_has_perm(sk_sid, port_sid, sk_class, send_perm, ad);
4499 }
4500
4501 static unsigned int selinux_ip_postroute_compat(struct sk_buff *skb,
4502                                                 int ifindex,
4503                                                 struct avc_audit_data *ad,
4504                                                 u16 family,
4505                                                 char *addrp,
4506                                                 u8 proto)
4507 {
4508         struct sock *sk = skb->sk;
4509         struct sk_security_struct *sksec;
4510
4511         if (sk == NULL)
4512                 return NF_ACCEPT;
4513         sksec = sk->sk_security;
4514
4515         if (selinux_compat_net) {
4516                 if (selinux_ip_postroute_iptables_compat(skb->sk, ifindex,
4517                                                          ad, family, addrp))
4518                         return NF_DROP;
4519         } else {
4520                 if (avc_has_perm(sksec->sid, skb->secmark,
4521                                  SECCLASS_PACKET, PACKET__SEND, ad))
4522                         return NF_DROP;
4523         }
4524
4525         if (selinux_policycap_netpeer)
4526                 if (selinux_xfrm_postroute_last(sksec->sid, skb, ad, proto))
4527                         return NF_DROP;
4528
4529         return NF_ACCEPT;
4530 }
4531
4532 static unsigned int selinux_ip_postroute(struct sk_buff *skb, int ifindex,
4533                                          u16 family)
4534 {
4535         u32 secmark_perm;
4536         u32 peer_sid;
4537         struct sock *sk;
4538         struct avc_audit_data ad;
4539         char *addrp;
4540         u8 proto;
4541         u8 secmark_active;
4542         u8 peerlbl_active;
4543
4544         AVC_AUDIT_DATA_INIT(&ad, NET);
4545         ad.u.net.netif = ifindex;
4546         ad.u.net.family = family;
4547         if (selinux_parse_skb(skb, &ad, &addrp, 0, &proto))
4548                 return NF_DROP;
4549
4550         /* If any sort of compatibility mode is enabled then handoff processing
4551          * to the selinux_ip_postroute_compat() function to deal with the
4552          * special handling.  We do this in an attempt to keep this function
4553          * as fast and as clean as possible. */
4554         if (selinux_compat_net || !selinux_policycap_netpeer)
4555                 return selinux_ip_postroute_compat(skb, ifindex, &ad,
4556                                                    family, addrp, proto);
4557
4558         /* If skb->dst->xfrm is non-NULL then the packet is undergoing an IPsec
4559          * packet transformation so allow the packet to pass without any checks
4560          * since we'll have another chance to perform access control checks
4561          * when the packet is on it's final way out.
4562          * NOTE: there appear to be some IPv6 multicast cases where skb->dst
4563          *       is NULL, in this case go ahead and apply access control. */
4564         if (skb->dst != NULL && skb->dst->xfrm != NULL)
4565                 return NF_ACCEPT;
4566
4567         secmark_active = selinux_secmark_enabled();
4568         peerlbl_active = netlbl_enabled() || selinux_xfrm_enabled();
4569         if (!secmark_active && !peerlbl_active)
4570                 return NF_ACCEPT;
4571
4572         /* if the packet is locally generated (skb->sk != NULL) then use the
4573          * socket's label as the peer label, otherwise the packet is being
4574          * forwarded through this system and we need to fetch the peer label
4575          * directly from the packet */
4576         sk = skb->sk;
4577         if (sk) {
4578                 struct sk_security_struct *sksec = sk->sk_security;
4579                 peer_sid = sksec->sid;
4580                 secmark_perm = PACKET__SEND;
4581         } else {
4582                 if (selinux_skb_peerlbl_sid(skb, family, &peer_sid))
4583                                 return NF_DROP;
4584                 secmark_perm = PACKET__FORWARD_OUT;
4585         }
4586
4587         if (secmark_active)
4588                 if (avc_has_perm(peer_sid, skb->secmark,
4589                                  SECCLASS_PACKET, secmark_perm, &ad))
4590                         return NF_DROP;
4591
4592         if (peerlbl_active) {
4593                 u32 if_sid;
4594                 u32 node_sid;
4595
4596                 if (sel_netif_sid(ifindex, &if_sid))
4597                         return NF_DROP;
4598                 if (avc_has_perm(peer_sid, if_sid,
4599                                  SECCLASS_NETIF, NETIF__EGRESS, &ad))
4600                         return NF_DROP;
4601
4602                 if (sel_netnode_sid(addrp, family, &node_sid))
4603                         return NF_DROP;
4604                 if (avc_has_perm(peer_sid, node_sid,
4605                                  SECCLASS_NODE, NODE__SENDTO, &ad))
4606                         return NF_DROP;
4607         }
4608
4609         return NF_ACCEPT;
4610 }
4611
4612 static unsigned int selinux_ipv4_postroute(unsigned int hooknum,
4613                                            struct sk_buff *skb,
4614                                            const struct net_device *in,
4615                                            const struct net_device *out,
4616                                            int (*okfn)(struct sk_buff *))
4617 {
4618         return selinux_ip_postroute(skb, out->ifindex, PF_INET);
4619 }
4620
4621 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
4622 static unsigned int selinux_ipv6_postroute(unsigned int hooknum,
4623                                            struct sk_buff *skb,
4624                                            const struct net_device *in,
4625                                            const struct net_device *out,
4626                                            int (*okfn)(struct sk_buff *))
4627 {
4628         return selinux_ip_postroute(skb, out->ifindex, PF_INET6);
4629 }
4630 #endif  /* IPV6 */
4631
4632 #endif  /* CONFIG_NETFILTER */
4633
4634 static int selinux_netlink_send(struct sock *sk, struct sk_buff *skb)
4635 {
4636         int err;
4637
4638         err = secondary_ops->netlink_send(sk, skb);
4639         if (err)
4640                 return err;
4641
4642         if (policydb_loaded_version >= POLICYDB_VERSION_NLCLASS)
4643                 err = selinux_nlmsg_perm(sk, skb);
4644
4645         return err;
4646 }
4647
4648 static int selinux_netlink_recv(struct sk_buff *skb, int capability)
4649 {
4650         int err;
4651         struct avc_audit_data ad;
4652
4653         err = secondary_ops->netlink_recv(skb, capability);
4654         if (err)
4655                 return err;
4656
4657         AVC_AUDIT_DATA_INIT(&ad, CAP);
4658         ad.u.cap = capability;
4659
4660         return avc_has_perm(NETLINK_CB(skb).sid, NETLINK_CB(skb).sid,
4661                             SECCLASS_CAPABILITY, CAP_TO_MASK(capability), &ad);
4662 }
4663
4664 static int ipc_alloc_security(struct task_struct *task,
4665                               struct kern_ipc_perm *perm,
4666                               u16 sclass)
4667 {
4668         struct task_security_struct *tsec = task->security;
4669         struct ipc_security_struct *isec;
4670
4671         isec = kzalloc(sizeof(struct ipc_security_struct), GFP_KERNEL);
4672         if (!isec)
4673                 return -ENOMEM;
4674
4675         isec->sclass = sclass;
4676         isec->sid = tsec->sid;
4677         perm->security = isec;
4678
4679         return 0;
4680 }
4681
4682 static void ipc_free_security(struct kern_ipc_perm *perm)
4683 {
4684         struct ipc_security_struct *isec = perm->security;
4685         perm->security = NULL;
4686         kfree(isec);
4687 }
4688
4689 static int msg_msg_alloc_security(struct msg_msg *msg)
4690 {
4691         struct msg_security_struct *msec;
4692
4693         msec = kzalloc(sizeof(struct msg_security_struct), GFP_KERNEL);
4694         if (!msec)
4695                 return -ENOMEM;
4696
4697         msec->sid = SECINITSID_UNLABELED;
4698         msg->security = msec;
4699
4700         return 0;
4701 }
4702
4703 static void msg_msg_free_security(struct msg_msg *msg)
4704 {
4705         struct msg_security_struct *msec = msg->security;
4706
4707         msg->security = NULL;
4708         kfree(msec);
4709 }
4710
4711 static int ipc_has_perm(struct kern_ipc_perm *ipc_perms,
4712                         u32 perms)
4713 {
4714         struct task_security_struct *tsec;
4715         struct ipc_security_struct *isec;
4716         struct avc_audit_data ad;
4717
4718         tsec = current->security;
4719         isec = ipc_perms->security;
4720
4721         AVC_AUDIT_DATA_INIT(&ad, IPC);
4722         ad.u.ipc_id = ipc_perms->key;
4723
4724         return avc_has_perm(tsec->sid, isec->sid, isec->sclass, perms, &ad);
4725 }
4726
4727 static int selinux_msg_msg_alloc_security(struct msg_msg *msg)
4728 {
4729         return msg_msg_alloc_security(msg);
4730 }
4731
4732 static void selinux_msg_msg_free_security(struct msg_msg *msg)
4733 {
4734         msg_msg_free_security(msg);
4735 }
4736
4737 /* message queue security operations */
4738 static int selinux_msg_queue_alloc_security(struct msg_queue *msq)
4739 {
4740         struct task_security_struct *tsec;
4741         struct ipc_security_struct *isec;
4742         struct avc_audit_data ad;
4743         int rc;
4744
4745         rc = ipc_alloc_security(current, &msq->q_perm, SECCLASS_MSGQ);
4746         if (rc)
4747                 return rc;
4748
4749         tsec = current->security;
4750         isec = msq->q_perm.security;
4751
4752         AVC_AUDIT_DATA_INIT(&ad, IPC);
4753         ad.u.ipc_id = msq->q_perm.key;
4754
4755         rc = avc_has_perm(tsec->sid, isec->sid, SECCLASS_MSGQ,
4756                           MSGQ__CREATE, &ad);
4757         if (rc) {
4758                 ipc_free_security(&msq->q_perm);
4759                 return rc;
4760         }
4761         return 0;
4762 }
4763
4764 static void selinux_msg_queue_free_security(struct msg_queue *msq)
4765 {
4766         ipc_free_security(&msq->q_perm);
4767 }
4768
4769 static int selinux_msg_queue_associate(struct msg_queue *msq, int msqflg)
4770 {
4771         struct task_security_struct *tsec;
4772         struct ipc_security_struct *isec;
4773         struct avc_audit_data ad;
4774
4775         tsec = current->security;
4776         isec = msq->q_perm.security;
4777
4778         AVC_AUDIT_DATA_INIT(&ad, IPC);
4779         ad.u.ipc_id = msq->q_perm.key;
4780
4781         return avc_has_perm(tsec->sid, isec->sid, SECCLASS_MSGQ,
4782                             MSGQ__ASSOCIATE, &ad);
4783 }
4784
4785 static int selinux_msg_queue_msgctl(struct msg_queue *msq, int cmd)
4786 {
4787         int err;
4788         int perms;
4789
4790         switch (cmd) {
4791         case IPC_INFO:
4792         case MSG_INFO:
4793                 /* No specific object, just general system-wide information. */
4794                 return task_has_system(current, SYSTEM__IPC_INFO);
4795         case IPC_STAT:
4796         case MSG_STAT:
4797                 perms = MSGQ__GETATTR | MSGQ__ASSOCIATE;
4798                 break;
4799         case IPC_SET:
4800                 perms = MSGQ__SETATTR;
4801                 break;
4802         case IPC_RMID:
4803                 perms = MSGQ__DESTROY;
4804                 break;
4805         default:
4806                 return 0;
4807         }
4808
4809         err = ipc_has_perm(&msq->q_perm, perms);
4810         return err;
4811 }
4812
4813 static int selinux_msg_queue_msgsnd(struct msg_queue *msq, struct msg_msg *msg, int msqflg)
4814 {
4815         struct task_security_struct *tsec;
4816         struct ipc_security_struct *isec;
4817         struct msg_security_struct *msec;
4818         struct avc_audit_data ad;
4819         int rc;
4820
4821         tsec = current->security;
4822         isec = msq->q_perm.security;
4823         msec = msg->security;
4824
4825         /*
4826          * First time through, need to assign label to the message
4827          */
4828         if (msec->sid == SECINITSID_UNLABELED) {
4829                 /*
4830                  * Compute new sid based on current process and
4831                  * message queue this message will be stored in
4832                  */
4833                 rc = security_transition_sid(tsec->sid,
4834                                              isec->sid,
4835                                              SECCLASS_MSG,
4836                                              &msec->sid);
4837                 if (rc)
4838                         return rc;
4839         }
4840
4841         AVC_AUDIT_DATA_INIT(&ad, IPC);
4842         ad.u.ipc_id = msq->q_perm.key;
4843
4844         /* Can this process write to the queue? */
4845         rc = avc_has_perm(tsec->sid, isec->sid, SECCLASS_MSGQ,
4846                           MSGQ__WRITE, &ad);
4847         if (!rc)
4848                 /* Can this process send the message */
4849                 rc = avc_has_perm(tsec->sid, msec->sid,
4850                                   SECCLASS_MSG, MSG__SEND, &ad);
4851         if (!rc)
4852                 /* Can the message be put in the queue? */
4853                 rc = avc_has_perm(msec->sid, isec->sid,
4854                                   SECCLASS_MSGQ, MSGQ__ENQUEUE, &ad);
4855
4856         return rc;
4857 }
4858
4859 static int selinux_msg_queue_msgrcv(struct msg_queue *msq, struct msg_msg *msg,
4860                                     struct task_struct *target,
4861                                     long type, int mode)
4862 {
4863         struct task_security_struct *tsec;
4864         struct ipc_security_struct *isec;
4865         struct msg_security_struct *msec;
4866         struct avc_audit_data ad;
4867         int rc;
4868
4869         tsec = target->security;
4870         isec = msq->q_perm.security;
4871         msec = msg->security;
4872
4873         AVC_AUDIT_DATA_INIT(&ad, IPC);
4874         ad.u.ipc_id = msq->q_perm.key;
4875
4876         rc = avc_has_perm(tsec->sid, isec->sid,
4877                           SECCLASS_MSGQ, MSGQ__READ, &ad);
4878         if (!rc)
4879                 rc = avc_has_perm(tsec->sid, msec->sid,
4880                                   SECCLASS_MSG, MSG__RECEIVE, &ad);
4881         return rc;
4882 }
4883
4884 /* Shared Memory security operations */
4885 static int selinux_shm_alloc_security(struct shmid_kernel *shp)
4886 {
4887         struct task_security_struct *tsec;
4888         struct ipc_security_struct *isec;
4889         struct avc_audit_data ad;
4890         int rc;
4891
4892         rc = ipc_alloc_security(current, &shp->shm_perm, SECCLASS_SHM);
4893         if (rc)
4894                 return rc;
4895
4896         tsec = current->security;
4897         isec = shp->shm_perm.security;
4898
4899         AVC_AUDIT_DATA_INIT(&ad, IPC);
4900         ad.u.ipc_id = shp->shm_perm.key;
4901
4902         rc = avc_has_perm(tsec->sid, isec->sid, SECCLASS_SHM,
4903                           SHM__CREATE, &ad);
4904         if (rc) {
4905                 ipc_free_security(&shp->shm_perm);
4906                 return rc;
4907         }
4908         return 0;
4909 }
4910
4911 static void selinux_shm_free_security(struct shmid_kernel *shp)
4912 {
4913         ipc_free_security(&shp->shm_perm);
4914 }
4915
4916 static int selinux_shm_associate(struct shmid_kernel *shp, int shmflg)
4917 {
4918         struct task_security_struct *tsec;
4919         struct ipc_security_struct *isec;
4920         struct avc_audit_data ad;
4921
4922         tsec = current->security;
4923         isec = shp->shm_perm.security;
4924
4925         AVC_AUDIT_DATA_INIT(&ad, IPC);
4926         ad.u.ipc_id = shp->shm_perm.key;
4927
4928         return avc_has_perm(tsec->sid, isec->sid, SECCLASS_SHM,
4929                             SHM__ASSOCIATE, &ad);
4930 }
4931
4932 /* Note, at this point, shp is locked down */
4933 static int selinux_shm_shmctl(struct shmid_kernel *shp, int cmd)
4934 {
4935         int perms;
4936         int err;
4937
4938         switch (cmd) {
4939         case IPC_INFO:
4940         case SHM_INFO:
4941                 /* No specific object, just general system-wide information. */
4942                 return task_has_system(current, SYSTEM__IPC_INFO);
4943         case IPC_STAT:
4944         case SHM_STAT:
4945                 perms = SHM__GETATTR | SHM__ASSOCIATE;
4946                 break;
4947         case IPC_SET:
4948                 perms = SHM__SETATTR;
4949                 break;
4950         case SHM_LOCK:
4951         case SHM_UNLOCK:
4952                 perms = SHM__LOCK;
4953                 break;
4954         case IPC_RMID:
4955                 perms = SHM__DESTROY;
4956                 break;
4957         default:
4958                 return 0;
4959         }
4960
4961         err = ipc_has_perm(&shp->shm_perm, perms);
4962         return err;
4963 }
4964
4965 static int selinux_shm_shmat(struct shmid_kernel *shp,
4966                              char __user *shmaddr, int shmflg)
4967 {
4968         u32 perms;
4969         int rc;
4970
4971         rc = secondary_ops->shm_shmat(shp, shmaddr, shmflg);
4972         if (rc)
4973                 return rc;
4974
4975         if (shmflg & SHM_RDONLY)
4976                 perms = SHM__READ;
4977         else
4978                 perms = SHM__READ | SHM__WRITE;
4979
4980         return ipc_has_perm(&shp->shm_perm, perms);
4981 }
4982
4983 /* Semaphore security operations */
4984 static int selinux_sem_alloc_security(struct sem_array *sma)
4985 {
4986         struct task_security_struct *tsec;
4987         struct ipc_security_struct *isec;
4988         struct avc_audit_data ad;
4989         int rc;
4990
4991         rc = ipc_alloc_security(current, &sma->sem_perm, SECCLASS_SEM);
4992         if (rc)
4993                 return rc;
4994
4995         tsec = current->security;
4996         isec = sma->sem_perm.security;
4997
4998         AVC_AUDIT_DATA_INIT(&ad, IPC);
4999         ad.u.ipc_id = sma->sem_perm.key;
5000
5001         rc = avc_has_perm(tsec->sid, isec->sid, SECCLASS_SEM,
5002                           SEM__CREATE, &ad);
5003         if (rc) {
5004                 ipc_free_security(&sma->sem_perm);
5005                 return rc;
5006         }
5007         return 0;
5008 }
5009
5010 static void selinux_sem_free_security(struct sem_array *sma)
5011 {
5012         ipc_free_security(&sma->sem_perm);
5013 }
5014
5015 static int selinux_sem_associate(struct sem_array *sma, int semflg)
5016 {
5017         struct task_security_struct *tsec;
5018         struct ipc_security_struct *isec;
5019         struct avc_audit_data ad;
5020
5021         tsec = current->security;
5022         isec = sma->sem_perm.security;
5023
5024         AVC_AUDIT_DATA_INIT(&ad, IPC);
5025         ad.u.ipc_id = sma->sem_perm.key;
5026
5027         return avc_has_perm(tsec->sid, isec->sid, SECCLASS_SEM,
5028                             SEM__ASSOCIATE, &ad);
5029 }
5030
5031 /* Note, at this point, sma is locked down */
5032 static int selinux_sem_semctl(struct sem_array *sma, int cmd)
5033 {
5034         int err;
5035         u32 perms;
5036
5037         switch (cmd) {
5038         case IPC_INFO:
5039         case SEM_INFO:
5040                 /* No specific object, just general system-wide information. */
5041                 return task_has_system(current, SYSTEM__IPC_INFO);
5042         case GETPID:
5043         case GETNCNT:
5044         case GETZCNT:
5045                 perms = SEM__GETATTR;
5046                 break;
5047         case GETVAL:
5048         case GETALL:
5049                 perms = SEM__READ;
5050                 break;
5051         case SETVAL:
5052         case SETALL:
5053                 perms = SEM__WRITE;
5054                 break;
5055         case IPC_RMID:
5056                 perms = SEM__DESTROY;
5057                 break;
5058         case IPC_SET:
5059                 perms = SEM__SETATTR;
5060                 break;
5061         case IPC_STAT:
5062         case SEM_STAT:
5063                 perms = SEM__GETATTR | SEM__ASSOCIATE;
5064                 break;
5065         default:
5066                 return 0;
5067         }
5068
5069         err = ipc_has_perm(&sma->sem_perm, perms);
5070         return err;
5071 }
5072
5073 static int selinux_sem_semop(struct sem_array *sma,
5074                              struct sembuf *sops, unsigned nsops, int alter)
5075 {
5076         u32 perms;
5077
5078         if (alter)
5079                 perms = SEM__READ | SEM__WRITE;
5080         else
5081                 perms = SEM__READ;
5082
5083         return ipc_has_perm(&sma->sem_perm, perms);
5084 }
5085
5086 static int selinux_ipc_permission(struct kern_ipc_perm *ipcp, short flag)
5087 {
5088         u32 av = 0;
5089
5090         av = 0;
5091         if (flag & S_IRUGO)
5092                 av |= IPC__UNIX_READ;
5093         if (flag & S_IWUGO)
5094                 av |= IPC__UNIX_WRITE;
5095
5096         if (av == 0)
5097                 return 0;
5098
5099         return ipc_has_perm(ipcp, av);
5100 }
5101
5102 static void selinux_ipc_getsecid(struct kern_ipc_perm *ipcp, u32 *secid)
5103 {
5104         struct ipc_security_struct *isec = ipcp->security;
5105         *secid = isec->sid;
5106 }
5107
5108 static void selinux_d_instantiate(struct dentry *dentry, struct inode *inode)
5109 {
5110         if (inode)
5111                 inode_doinit_with_dentry(inode, dentry);
5112 }
5113
5114 static int selinux_getprocattr(struct task_struct *p,
5115                                char *name, char **value)
5116 {
5117         struct task_security_struct *tsec;
5118         u32 sid;
5119         int error;
5120         unsigned len;
5121
5122         if (current != p) {
5123                 error = task_has_perm(current, p, PROCESS__GETATTR);
5124                 if (error)
5125                         return error;
5126         }
5127
5128         tsec = p->security;
5129
5130         if (!strcmp(name, "current"))
5131                 sid = tsec->sid;
5132         else if (!strcmp(name, "prev"))
5133                 sid = tsec->osid;
5134         else if (!strcmp(name, "exec"))
5135                 sid = tsec->exec_sid;
5136         else if (!strcmp(name, "fscreate"))
5137                 sid = tsec->create_sid;
5138         else if (!strcmp(name, "keycreate"))
5139                 sid = tsec->keycreate_sid;
5140         else if (!strcmp(name, "sockcreate"))
5141                 sid = tsec->sockcreate_sid;
5142         else
5143                 return -EINVAL;
5144
5145         if (!sid)
5146                 return 0;
5147
5148         error = security_sid_to_context(sid, value, &len);
5149         if (error)
5150                 return error;
5151         return len;
5152 }
5153
5154 static int selinux_setprocattr(struct task_struct *p,
5155                                char *name, void *value, size_t size)
5156 {
5157         struct task_security_struct *tsec;
5158         struct task_struct *tracer;
5159         u32 sid = 0;
5160         int error;
5161         char *str = value;
5162
5163         if (current != p) {
5164                 /* SELinux only allows a process to change its own
5165                    security attributes. */
5166                 return -EACCES;
5167         }
5168
5169         /*
5170          * Basic control over ability to set these attributes at all.
5171          * current == p, but we'll pass them separately in case the
5172          * above restriction is ever removed.
5173          */
5174         if (!strcmp(name, "exec"))
5175                 error = task_has_perm(current, p, PROCESS__SETEXEC);
5176         else if (!strcmp(name, "fscreate"))
5177                 error = task_has_perm(current, p, PROCESS__SETFSCREATE);
5178         else if (!strcmp(name, "keycreate"))
5179                 error = task_has_perm(current, p, PROCESS__SETKEYCREATE);
5180         else if (!strcmp(name, "sockcreate"))
5181                 error = task_has_perm(current, p, PROCESS__SETSOCKCREATE);
5182         else if (!strcmp(name, "current"))
5183                 error = task_has_perm(current, p, PROCESS__SETCURRENT);
5184         else
5185                 error = -EINVAL;
5186         if (error)
5187                 return error;
5188
5189         /* Obtain a SID for the context, if one was specified. */
5190         if (size && str[1] && str[1] != '\n') {
5191                 if (str[size-1] == '\n') {
5192                         str[size-1] = 0;
5193                         size--;
5194                 }
5195                 error = security_context_to_sid(value, size, &sid);
5196                 if (error == -EINVAL && !strcmp(name, "fscreate")) {
5197                         if (!capable(CAP_MAC_ADMIN))
5198                                 return error;
5199                         error = security_context_to_sid_force(value, size,
5200                                                               &sid);
5201                 }
5202                 if (error)
5203                         return error;
5204         }
5205
5206         /* Permission checking based on the specified context is
5207            performed during the actual operation (execve,
5208            open/mkdir/...), when we know the full context of the
5209            operation.  See selinux_bprm_set_security for the execve
5210            checks and may_create for the file creation checks. The
5211            operation will then fail if the context is not permitted. */
5212         tsec = p->security;
5213         if (!strcmp(name, "exec"))
5214                 tsec->exec_sid = sid;
5215         else if (!strcmp(name, "fscreate"))
5216                 tsec->create_sid = sid;
5217         else if (!strcmp(name, "keycreate")) {
5218                 error = may_create_key(sid, p);
5219                 if (error)
5220                         return error;
5221                 tsec->keycreate_sid = sid;
5222         } else if (!strcmp(name, "sockcreate"))
5223                 tsec->sockcreate_sid = sid;
5224         else if (!strcmp(name, "current")) {
5225                 struct av_decision avd;
5226
5227                 if (sid == 0)
5228                         return -EINVAL;
5229                 /*
5230                  * SELinux allows to change context in the following case only.
5231                  *  - Single threaded processes.
5232                  *  - Multi threaded processes intend to change its context into
5233                  *    more restricted domain (defined by TYPEBOUNDS statement).
5234                  */
5235                 if (atomic_read(&p->mm->mm_users) != 1) {
5236                         struct task_struct *g, *t;
5237                         struct mm_struct *mm = p->mm;
5238                         read_lock(&tasklist_lock);
5239                         do_each_thread(g, t) {
5240                                 if (t->mm == mm && t != p) {
5241                                         read_unlock(&tasklist_lock);
5242                                         error = security_bounded_transition(tsec->sid, sid);
5243                                         if (!error)
5244                                                 goto boundary_ok;
5245
5246                                         return error;
5247                                 }
5248                         } while_each_thread(g, t);
5249                         read_unlock(&tasklist_lock);
5250                 }
5251 boundary_ok:
5252
5253                 /* Check permissions for the transition. */
5254                 error = avc_has_perm(tsec->sid, sid, SECCLASS_PROCESS,
5255                                      PROCESS__DYNTRANSITION, NULL);
5256                 if (error)
5257                         return error;
5258
5259                 /* Check for ptracing, and update the task SID if ok.
5260                    Otherwise, leave SID unchanged and fail. */
5261                 task_lock(p);
5262                 rcu_read_lock();
5263                 tracer = tracehook_tracer_task(p);
5264                 if (tracer != NULL) {
5265                         struct task_security_struct *ptsec = tracer->security;
5266                         u32 ptsid = ptsec->sid;
5267                         rcu_read_unlock();
5268                         error = avc_has_perm_noaudit(ptsid, sid,
5269                                                      SECCLASS_PROCESS,
5270                                                      PROCESS__PTRACE, 0, &avd);
5271                         if (!error)
5272                                 tsec->sid = sid;
5273                         task_unlock(p);
5274                         avc_audit(ptsid, sid, SECCLASS_PROCESS,
5275                                   PROCESS__PTRACE, &avd, error, NULL);
5276                         if (error)
5277                                 return error;
5278                 } else {
5279                         rcu_read_unlock();
5280                         tsec->sid = sid;
5281                         task_unlock(p);
5282                 }
5283         } else
5284                 return -EINVAL;
5285
5286         return size;
5287 }
5288
5289 static int selinux_secid_to_secctx(u32 secid, char **secdata, u32 *seclen)
5290 {
5291         return security_sid_to_context(secid, secdata, seclen);
5292 }
5293
5294 static int selinux_secctx_to_secid(const char *secdata, u32 seclen, u32 *secid)
5295 {
5296         return security_context_to_sid(secdata, seclen, secid);
5297 }
5298
5299 static void selinux_release_secctx(char *secdata, u32 seclen)
5300 {
5301         kfree(secdata);
5302 }
5303
5304 #ifdef CONFIG_KEYS
5305
5306 static int selinux_key_alloc(struct key *k, struct task_struct *tsk,
5307                              unsigned long flags)
5308 {
5309         struct task_security_struct *tsec = tsk->security;
5310         struct key_security_struct *ksec;
5311
5312         ksec = kzalloc(sizeof(struct key_security_struct), GFP_KERNEL);
5313         if (!ksec)
5314                 return -ENOMEM;
5315
5316         if (tsec->keycreate_sid)
5317                 ksec->sid = tsec->keycreate_sid;
5318         else
5319                 ksec->sid = tsec->sid;
5320         k->security = ksec;
5321
5322         return 0;
5323 }
5324
5325 static void selinux_key_free(struct key *k)
5326 {
5327         struct key_security_struct *ksec = k->security;
5328
5329         k->security = NULL;
5330         kfree(ksec);
5331 }
5332
5333 static int selinux_key_permission(key_ref_t key_ref,
5334                             struct task_struct *ctx,
5335                             key_perm_t perm)
5336 {
5337         struct key *key;
5338         struct task_security_struct *tsec;
5339         struct key_security_struct *ksec;
5340
5341         key = key_ref_to_ptr(key_ref);
5342
5343         tsec = ctx->security;
5344         ksec = key->security;
5345
5346         /* if no specific permissions are requested, we skip the
5347            permission check. No serious, additional covert channels
5348            appear to be created. */
5349         if (perm == 0)
5350                 return 0;
5351
5352         return avc_has_perm(tsec->sid, ksec->sid,
5353                             SECCLASS_KEY, perm, NULL);
5354 }
5355
5356 static int selinux_key_getsecurity(struct key *key, char **_buffer)
5357 {
5358         struct key_security_struct *ksec = key->security;
5359         char *context = NULL;
5360         unsigned len;
5361         int rc;
5362
5363         rc = security_sid_to_context(ksec->sid, &context, &len);
5364         if (!rc)
5365                 rc = len;
5366         *_buffer = context;
5367         return rc;
5368 }
5369
5370 #endif
5371
5372 static struct security_operations selinux_ops = {
5373         .name =                         "selinux",
5374
5375         .ptrace_may_access =            selinux_ptrace_may_access,
5376         .ptrace_traceme =               selinux_ptrace_traceme,
5377         .capget =                       selinux_capget,
5378         .capset_check =                 selinux_capset_check,
5379         .capset_set =                   selinux_capset_set,
5380         .sysctl =                       selinux_sysctl,
5381         .capable =                      selinux_capable,
5382         .quotactl =                     selinux_quotactl,
5383         .quota_on =                     selinux_quota_on,
5384         .syslog =                       selinux_syslog,
5385         .vm_enough_memory =             selinux_vm_enough_memory,
5386
5387         .netlink_send =                 selinux_netlink_send,
5388         .netlink_recv =                 selinux_netlink_recv,
5389
5390         .bprm_alloc_security =          selinux_bprm_alloc_security,
5391         .bprm_free_security =           selinux_bprm_free_security,
5392         .bprm_apply_creds =             selinux_bprm_apply_creds,
5393         .bprm_post_apply_creds =        selinux_bprm_post_apply_creds,
5394         .bprm_set_security =            selinux_bprm_set_security,
5395         .bprm_check_security =          selinux_bprm_check_security,
5396         .bprm_secureexec =              selinux_bprm_secureexec,
5397
5398         .sb_alloc_security =            selinux_sb_alloc_security,
5399         .sb_free_security =             selinux_sb_free_security,
5400         .sb_copy_data =                 selinux_sb_copy_data,
5401         .sb_kern_mount =                selinux_sb_kern_mount,
5402         .sb_show_options =              selinux_sb_show_options,
5403         .sb_statfs =                    selinux_sb_statfs,
5404         .sb_mount =                     selinux_mount,
5405         .sb_umount =                    selinux_umount,
5406         .sb_set_mnt_opts =              selinux_set_mnt_opts,
5407         .sb_clone_mnt_opts =            selinux_sb_clone_mnt_opts,
5408         .sb_parse_opts_str =            selinux_parse_opts_str,
5409
5410
5411         .inode_alloc_security =         selinux_inode_alloc_security,
5412         .inode_free_security =          selinux_inode_free_security,
5413         .inode_init_security =          selinux_inode_init_security,
5414         .inode_create =                 selinux_inode_create,
5415         .inode_link =                   selinux_inode_link,
5416         .inode_unlink =                 selinux_inode_unlink,
5417         .inode_symlink =                selinux_inode_symlink,
5418         .inode_mkdir =                  selinux_inode_mkdir,
5419         .inode_rmdir =                  selinux_inode_rmdir,
5420         .inode_mknod =                  selinux_inode_mknod,
5421         .inode_rename =                 selinux_inode_rename,
5422         .inode_readlink =               selinux_inode_readlink,
5423         .inode_follow_link =            selinux_inode_follow_link,
5424         .inode_permission =             selinux_inode_permission,
5425         .inode_setattr =                selinux_inode_setattr,
5426         .inode_getattr =                selinux_inode_getattr,
5427         .inode_setxattr =               selinux_inode_setxattr,
5428         .inode_post_setxattr =          selinux_inode_post_setxattr,
5429         .inode_getxattr =               selinux_inode_getxattr,
5430         .inode_listxattr =              selinux_inode_listxattr,
5431         .inode_removexattr =            selinux_inode_removexattr,
5432         .inode_getsecurity =            selinux_inode_getsecurity,
5433         .inode_setsecurity =            selinux_inode_setsecurity,
5434         .inode_listsecurity =           selinux_inode_listsecurity,
5435         .inode_need_killpriv =          selinux_inode_need_killpriv,
5436         .inode_killpriv =               selinux_inode_killpriv,
5437         .inode_getsecid =               selinux_inode_getsecid,
5438
5439         .file_permission =              selinux_file_permission,
5440         .file_alloc_security =          selinux_file_alloc_security,
5441         .file_free_security =           selinux_file_free_security,
5442         .file_ioctl =                   selinux_file_ioctl,
5443         .file_mmap =                    selinux_file_mmap,
5444         .file_mprotect =                selinux_file_mprotect,
5445         .file_lock =                    selinux_file_lock,
5446         .file_fcntl =                   selinux_file_fcntl,
5447         .file_set_fowner =              selinux_file_set_fowner,
5448         .file_send_sigiotask =          selinux_file_send_sigiotask,
5449         .file_receive =                 selinux_file_receive,
5450
5451         .dentry_open =                  selinux_dentry_open,
5452
5453         .task_create =                  selinux_task_create,
5454         .task_alloc_security =          selinux_task_alloc_security,
5455         .task_free_security =           selinux_task_free_security,
5456         .task_setuid =                  selinux_task_setuid,
5457         .task_post_setuid =             selinux_task_post_setuid,
5458         .task_setgid =                  selinux_task_setgid,
5459         .task_setpgid =                 selinux_task_setpgid,
5460         .task_getpgid =                 selinux_task_getpgid,
5461         .task_getsid =                  selinux_task_getsid,
5462         .task_getsecid =                selinux_task_getsecid,
5463         .task_setgroups =               selinux_task_setgroups,
5464         .task_setnice =                 selinux_task_setnice,
5465         .task_setioprio =               selinux_task_setioprio,
5466         .task_getioprio =               selinux_task_getioprio,
5467         .task_setrlimit =               selinux_task_setrlimit,
5468         .task_setscheduler =            selinux_task_setscheduler,
5469         .task_getscheduler =            selinux_task_getscheduler,
5470         .task_movememory =              selinux_task_movememory,
5471         .task_kill =                    selinux_task_kill,
5472         .task_wait =                    selinux_task_wait,
5473         .task_prctl =                   selinux_task_prctl,
5474         .task_reparent_to_init =        selinux_task_reparent_to_init,
5475         .task_to_inode =                selinux_task_to_inode,
5476
5477         .ipc_permission =               selinux_ipc_permission,
5478         .ipc_getsecid =                 selinux_ipc_getsecid,
5479
5480         .msg_msg_alloc_security =       selinux_msg_msg_alloc_security,
5481         .msg_msg_free_security =        selinux_msg_msg_free_security,
5482
5483         .msg_queue_alloc_security =     selinux_msg_queue_alloc_security,
5484         .msg_queue_free_security =      selinux_msg_queue_free_security,
5485         .msg_queue_associate =          selinux_msg_queue_associate,
5486         .msg_queue_msgctl =             selinux_msg_queue_msgctl,
5487         .msg_queue_msgsnd =             selinux_msg_queue_msgsnd,
5488         .msg_queue_msgrcv =             selinux_msg_queue_msgrcv,
5489
5490         .shm_alloc_security =           selinux_shm_alloc_security,
5491         .shm_free_security =            selinux_shm_free_security,
5492         .shm_associate =                selinux_shm_associate,
5493         .shm_shmctl =                   selinux_shm_shmctl,
5494         .shm_shmat =                    selinux_shm_shmat,
5495
5496         .sem_alloc_security =           selinux_sem_alloc_security,
5497         .sem_free_security =            selinux_sem_free_security,
5498         .sem_associate =                selinux_sem_associate,
5499         .sem_semctl =                   selinux_sem_semctl,
5500         .sem_semop =                    selinux_sem_semop,
5501
5502         .d_instantiate =                selinux_d_instantiate,
5503
5504         .getprocattr =                  selinux_getprocattr,
5505         .setprocattr =                  selinux_setprocattr,
5506
5507         .secid_to_secctx =              selinux_secid_to_secctx,
5508         .secctx_to_secid =              selinux_secctx_to_secid,
5509         .release_secctx =               selinux_release_secctx,
5510
5511         .unix_stream_connect =          selinux_socket_unix_stream_connect,
5512         .unix_may_send =                selinux_socket_unix_may_send,
5513
5514         .socket_create =                selinux_socket_create,
5515         .socket_post_create =           selinux_socket_post_create,
5516         .socket_bind =                  selinux_socket_bind,
5517         .socket_connect =               selinux_socket_connect,
5518         .socket_listen =                selinux_socket_listen,
5519         .socket_accept =                selinux_socket_accept,
5520         .socket_sendmsg =               selinux_socket_sendmsg,
5521         .socket_recvmsg =               selinux_socket_recvmsg,
5522         .socket_getsockname =           selinux_socket_getsockname,
5523         .socket_getpeername =           selinux_socket_getpeername,
5524         .socket_getsockopt =            selinux_socket_getsockopt,
5525         .socket_setsockopt =            selinux_socket_setsockopt,
5526         .socket_shutdown =              selinux_socket_shutdown,
5527         .socket_sock_rcv_skb =          selinux_socket_sock_rcv_skb,
5528         .socket_getpeersec_stream =     selinux_socket_getpeersec_stream,
5529         .socket_getpeersec_dgram =      selinux_socket_getpeersec_dgram,
5530         .sk_alloc_security =            selinux_sk_alloc_security,
5531         .sk_free_security =             selinux_sk_free_security,
5532         .sk_clone_security =            selinux_sk_clone_security,
5533         .sk_getsecid =                  selinux_sk_getsecid,
5534         .sock_graft =                   selinux_sock_graft,
5535         .inet_conn_request =            selinux_inet_conn_request,
5536         .inet_csk_clone =               selinux_inet_csk_clone,
5537         .inet_conn_established =        selinux_inet_conn_established,
5538         .req_classify_flow =            selinux_req_classify_flow,
5539
5540 #ifdef CONFIG_SECURITY_NETWORK_XFRM
5541         .xfrm_policy_alloc_security =   selinux_xfrm_policy_alloc,
5542         .xfrm_policy_clone_security =   selinux_xfrm_policy_clone,
5543         .xfrm_policy_free_security =    selinux_xfrm_policy_free,
5544         .xfrm_policy_delete_security =  selinux_xfrm_policy_delete,
5545         .xfrm_state_alloc_security =    selinux_xfrm_state_alloc,
5546         .xfrm_state_free_security =     selinux_xfrm_state_free,
5547         .xfrm_state_delete_security =   selinux_xfrm_state_delete,
5548         .xfrm_policy_lookup =           selinux_xfrm_policy_lookup,
5549         .xfrm_state_pol_flow_match =    selinux_xfrm_state_pol_flow_match,
5550         .xfrm_decode_session =          selinux_xfrm_decode_session,
5551 #endif
5552
5553 #ifdef CONFIG_KEYS
5554         .key_alloc =                    selinux_key_alloc,
5555         .key_free =                     selinux_key_free,
5556         .key_permission =               selinux_key_permission,
5557         .key_getsecurity =              selinux_key_getsecurity,
5558 #endif
5559
5560 #ifdef CONFIG_AUDIT
5561         .audit_rule_init =              selinux_audit_rule_init,
5562         .audit_rule_known =             selinux_audit_rule_known,
5563         .audit_rule_match =             selinux_audit_rule_match,
5564         .audit_rule_free =              selinux_audit_rule_free,
5565 #endif
5566 };
5567
5568 static __init int selinux_init(void)
5569 {
5570         struct task_security_struct *tsec;
5571
5572         if (!security_module_enable(&selinux_ops)) {
5573                 selinux_enabled = 0;
5574                 return 0;
5575         }
5576
5577         if (!selinux_enabled) {
5578                 printk(KERN_INFO "SELinux:  Disabled at boot.\n");
5579                 return 0;
5580         }
5581
5582         printk(KERN_INFO "SELinux:  Initializing.\n");
5583
5584         /* Set the security state for the initial task. */
5585         if (task_alloc_security(current))
5586                 panic("SELinux:  Failed to initialize initial task.\n");
5587         tsec = current->security;
5588         tsec->osid = tsec->sid = SECINITSID_KERNEL;
5589
5590         sel_inode_cache = kmem_cache_create("selinux_inode_security",
5591                                             sizeof(struct inode_security_struct),
5592                                             0, SLAB_PANIC, NULL);
5593         avc_init();
5594
5595         secondary_ops = security_ops;
5596         if (!secondary_ops)
5597                 panic("SELinux: No initial security operations\n");
5598         if (register_security(&selinux_ops))
5599                 panic("SELinux: Unable to register with kernel.\n");
5600
5601         if (selinux_enforcing)
5602                 printk(KERN_DEBUG "SELinux:  Starting in enforcing mode\n");
5603         else
5604                 printk(KERN_DEBUG "SELinux:  Starting in permissive mode\n");
5605
5606         return 0;
5607 }
5608
5609 void selinux_complete_init(void)
5610 {
5611         printk(KERN_DEBUG "SELinux:  Completing initialization.\n");
5612
5613         /* Set up any superblocks initialized prior to the policy load. */
5614         printk(KERN_DEBUG "SELinux:  Setting up existing superblocks.\n");
5615         spin_lock(&sb_lock);
5616         spin_lock(&sb_security_lock);
5617 next_sb:
5618         if (!list_empty(&superblock_security_head)) {
5619                 struct superblock_security_struct *sbsec =
5620                                 list_entry(superblock_security_head.next,
5621                                            struct superblock_security_struct,
5622                                            list);
5623                 struct super_block *sb = sbsec->sb;
5624                 sb->s_count++;
5625                 spin_unlock(&sb_security_lock);
5626                 spin_unlock(&sb_lock);
5627                 down_read(&sb->s_umount);
5628                 if (sb->s_root)
5629                         superblock_doinit(sb, NULL);
5630                 drop_super(sb);
5631                 spin_lock(&sb_lock);
5632                 spin_lock(&sb_security_lock);
5633                 list_del_init(&sbsec->list);
5634                 goto next_sb;
5635         }
5636         spin_unlock(&sb_security_lock);
5637         spin_unlock(&sb_lock);
5638 }
5639
5640 /* SELinux requires early initialization in order to label
5641    all processes and objects when they are created. */
5642 security_initcall(selinux_init);
5643
5644 #if defined(CONFIG_NETFILTER)
5645
5646 static struct nf_hook_ops selinux_ipv4_ops[] = {
5647         {
5648                 .hook =         selinux_ipv4_postroute,
5649                 .owner =        THIS_MODULE,
5650                 .pf =           PF_INET,
5651                 .hooknum =      NF_INET_POST_ROUTING,
5652                 .priority =     NF_IP_PRI_SELINUX_LAST,
5653         },
5654         {
5655                 .hook =         selinux_ipv4_forward,
5656                 .owner =        THIS_MODULE,
5657                 .pf =           PF_INET,
5658                 .hooknum =      NF_INET_FORWARD,
5659                 .priority =     NF_IP_PRI_SELINUX_FIRST,
5660         }
5661 };
5662
5663 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
5664
5665 static struct nf_hook_ops selinux_ipv6_ops[] = {
5666         {
5667                 .hook =         selinux_ipv6_postroute,
5668                 .owner =        THIS_MODULE,
5669                 .pf =           PF_INET6,
5670                 .hooknum =      NF_INET_POST_ROUTING,
5671                 .priority =     NF_IP6_PRI_SELINUX_LAST,
5672         },
5673         {
5674                 .hook =         selinux_ipv6_forward,
5675                 .owner =        THIS_MODULE,
5676                 .pf =           PF_INET6,
5677                 .hooknum =      NF_INET_FORWARD,
5678                 .priority =     NF_IP6_PRI_SELINUX_FIRST,
5679         }
5680 };
5681
5682 #endif  /* IPV6 */
5683
5684 static int __init selinux_nf_ip_init(void)
5685 {
5686         int err = 0;
5687
5688         if (!selinux_enabled)
5689                 goto out;
5690
5691         printk(KERN_DEBUG "SELinux:  Registering netfilter hooks\n");
5692
5693         err = nf_register_hooks(selinux_ipv4_ops, ARRAY_SIZE(selinux_ipv4_ops));
5694         if (err)
5695                 panic("SELinux: nf_register_hooks for IPv4: error %d\n", err);
5696
5697 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
5698         err = nf_register_hooks(selinux_ipv6_ops, ARRAY_SIZE(selinux_ipv6_ops));
5699         if (err)
5700                 panic("SELinux: nf_register_hooks for IPv6: error %d\n", err);
5701 #endif  /* IPV6 */
5702
5703 out:
5704         return err;
5705 }
5706
5707 __initcall(selinux_nf_ip_init);
5708
5709 #ifdef CONFIG_SECURITY_SELINUX_DISABLE
5710 static void selinux_nf_ip_exit(void)
5711 {
5712         printk(KERN_DEBUG "SELinux:  Unregistering netfilter hooks\n");
5713
5714         nf_unregister_hooks(selinux_ipv4_ops, ARRAY_SIZE(selinux_ipv4_ops));
5715 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
5716         nf_unregister_hooks(selinux_ipv6_ops, ARRAY_SIZE(selinux_ipv6_ops));
5717 #endif  /* IPV6 */
5718 }
5719 #endif
5720
5721 #else /* CONFIG_NETFILTER */
5722
5723 #ifdef CONFIG_SECURITY_SELINUX_DISABLE
5724 #define selinux_nf_ip_exit()
5725 #endif
5726
5727 #endif /* CONFIG_NETFILTER */
5728
5729 #ifdef CONFIG_SECURITY_SELINUX_DISABLE
5730 static int selinux_disabled;
5731
5732 int selinux_disable(void)
5733 {
5734         extern void exit_sel_fs(void);
5735
5736         if (ss_initialized) {
5737                 /* Not permitted after initial policy load. */
5738                 return -EINVAL;
5739         }
5740
5741         if (selinux_disabled) {
5742                 /* Only do this once. */
5743                 return -EINVAL;
5744         }
5745
5746         printk(KERN_INFO "SELinux:  Disabled at runtime.\n");
5747
5748         selinux_disabled = 1;
5749         selinux_enabled = 0;
5750
5751         /* Reset security_ops to the secondary module, dummy or capability. */
5752         security_ops = secondary_ops;
5753
5754         /* Unregister netfilter hooks. */
5755         selinux_nf_ip_exit();
5756
5757         /* Unregister selinuxfs. */
5758         exit_sel_fs();
5759
5760         return 0;
5761 }
5762 #endif