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, 2009 Hewlett-Packard Development Company, L.P.
  17  *      Paul Moore <paul.moore@hp.com>
  18  *  Copyright (C) 2007 Hitachi Software Engineering Co., Ltd.
  19  *                     Yuichi Nakamura <ynakam@hitachisoft.jp>
  20  *
  21  *      This program is free software; you can redistribute it and/or modify
  22  *      it under the terms of the GNU General Public License version 2,
  23  *      as published by the Free Software Foundation.
  24  */
  25
  26 #include <linux/init.h>
  27 #include <linux/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 #include <linux/posix-timers.h>
  79 #include <linux/syslog.h>
  80
  81 #include "avc.h"
  82 #include "objsec.h"
  83 #include "netif.h"
  84 #include "netnode.h"
  85 #include "netport.h"
  86 #include "xfrm.h"
  87 #include "netlabel.h"
  88 #include "audit.h"
  89
  90 #define NUM_SEL_MNT_OPTS 5
  91
  92 extern int selinux_nlmsg_lookup(u16 sclass, u16 nlmsg_type, u32 *perm);
  93 extern struct security_operations *security_ops;
  94
  95 /* SECMARK reference count */
  96 atomic_t selinux_secmark_refcount = ATOMIC_INIT(0);
  97
  98 #ifdef CONFIG_SECURITY_SELINUX_DEVELOP
  99 int selinux_enforcing;
 100
 101 static int __init enforcing_setup(char *str)
 102 {
 103         unsigned long enforcing;
 104         if (!strict_strtoul(str, 0, &enforcing))
 105                 selinux_enforcing = enforcing ? 1 : 0;
 106         return 1;
 107 }
 108 __setup("enforcing=", enforcing_setup);
 109 #endif
 110
 111 #ifdef CONFIG_SECURITY_SELINUX_BOOTPARAM
 112 int selinux_enabled = CONFIG_SECURITY_SELINUX_BOOTPARAM_VALUE;
 113
 114 static int __init selinux_enabled_setup(char *str)
 115 {
 116         unsigned long enabled;
 117         if (!strict_strtoul(str, 0, &enabled))
 118                 selinux_enabled = enabled ? 1 : 0;
 119         return 1;
 120 }
 121 __setup("selinux=", selinux_enabled_setup);
 122 #else
 123 int selinux_enabled = 1;
 124 #endif
 125
 126 static struct kmem_cache *sel_inode_cache;
 127
 128 /**
 129  * selinux_secmark_enabled - Check to see if SECMARK is currently enabled
 130  *
 131  * Description:
 132  * This function checks the SECMARK reference counter to see if any SECMARK
 133  * targets are currently configured, if the reference counter is greater than
 134  * zero SECMARK is considered to be enabled.  Returns true (1) if SECMARK is
 135  * enabled, false (0) if SECMARK is disabled.
 136  *
 137  */
 138 static int selinux_secmark_enabled(void)
 139 {
 140         return (atomic_read(&selinux_secmark_refcount) > 0);
 141 }
 142
 143 /*
 144  * initialise the security for the init task
 145  */
 146 static void cred_init_security(void)
 147 {
 148         struct cred *cred = (struct cred *) current->real_cred;
 149         struct task_security_struct *tsec;
 150
 151         tsec = kzalloc(sizeof(struct task_security_struct), GFP_KERNEL);
 152         if (!tsec)
 153                 panic("SELinux:  Failed to initialize initial task.\n");
 154
 155         tsec->osid = tsec->sid = SECINITSID_KERNEL;
 156         cred->security = tsec;
 157 }
 158
 159 /*
 160  * get the security ID of a set of credentials
 161  */
 162 static inline u32 cred_sid(const struct cred *cred)
 163 {
 164         const struct task_security_struct *tsec;
 165
 166         tsec = cred->security;
 167         return tsec->sid;
 168 }
 169
 170 /*
 171  * get the objective security ID of a task
 172  */
 173 static inline u32 task_sid(const struct task_struct *task)
 174 {
 175         u32 sid;
 176
 177         rcu_read_lock();
 178         sid = cred_sid(__task_cred(task));
 179         rcu_read_unlock();
 180         return sid;
 181 }
 182
 183 /*
 184  * get the subjective security ID of the current task
 185  */
 186 static inline u32 current_sid(void)
 187 {
 188         const struct task_security_struct *tsec = current_security();
 189
 190         return tsec->sid;
 191 }
 192
 193 /* Allocate and free functions for each kind of security blob. */
 194
 195 static int inode_alloc_security(struct inode *inode)
 196 {
 197         struct inode_security_struct *isec;
 198         u32 sid = current_sid();
 199
 200         isec = kmem_cache_zalloc(sel_inode_cache, GFP_NOFS);
 201         if (!isec)
 202                 return -ENOMEM;
 203
 204         mutex_init(&isec->lock);
 205         INIT_LIST_HEAD(&isec->list);
 206         isec->inode = inode;
 207         isec->sid = SECINITSID_UNLABELED;
 208         isec->sclass = SECCLASS_FILE;
 209         isec->task_sid = sid;
 210         inode->i_security = isec;
 211
 212         return 0;
 213 }
 214
 215 static void inode_free_security(struct inode *inode)
 216 {
 217         struct inode_security_struct *isec = inode->i_security;
 218         struct superblock_security_struct *sbsec = inode->i_sb->s_security;
 219
 220         spin_lock(&sbsec->isec_lock);
 221         if (!list_empty(&isec->list))
 222                 list_del_init(&isec->list);
 223         spin_unlock(&sbsec->isec_lock);
 224
 225         inode->i_security = NULL;
 226         kmem_cache_free(sel_inode_cache, isec);
 227 }
 228
 229 static int file_alloc_security(struct file *file)
 230 {
 231         struct file_security_struct *fsec;
 232         u32 sid = current_sid();
 233
 234         fsec = kzalloc(sizeof(struct file_security_struct), GFP_KERNEL);
 235         if (!fsec)
 236                 return -ENOMEM;
 237
 238         fsec->sid = sid;
 239         fsec->fown_sid = sid;
 240         file->f_security = fsec;
 241
 242         return 0;
 243 }
 244
 245 static void file_free_security(struct file *file)
 246 {
 247         struct file_security_struct *fsec = file->f_security;
 248         file->f_security = NULL;
 249         kfree(fsec);
 250 }
 251
 252 static int superblock_alloc_security(struct super_block *sb)
 253 {
 254         struct superblock_security_struct *sbsec;
 255
 256         sbsec = kzalloc(sizeof(struct superblock_security_struct), GFP_KERNEL);
 257         if (!sbsec)
 258                 return -ENOMEM;
 259
 260         mutex_init(&sbsec->lock);
 261         INIT_LIST_HEAD(&sbsec->isec_head);
 262         spin_lock_init(&sbsec->isec_lock);
 263         sbsec->sb = sb;
 264         sbsec->sid = SECINITSID_UNLABELED;
 265         sbsec->def_sid = SECINITSID_FILE;
 266         sbsec->mntpoint_sid = SECINITSID_UNLABELED;
 267         sb->s_security = sbsec;
 268
 269         return 0;
 270 }
 271
 272 static void superblock_free_security(struct super_block *sb)
 273 {
 274         struct superblock_security_struct *sbsec = sb->s_security;
 275         sb->s_security = NULL;
 276         kfree(sbsec);
 277 }
 278
 279 /* The security server must be initialized before
 280    any labeling or access decisions can be provided. */
 281 extern int ss_initialized;
 282
 283 /* The file system's label must be initialized prior to use. */
 284
 285 static const char *labeling_behaviors[6] = {
 286         "uses xattr",
 287         "uses transition SIDs",
 288         "uses task SIDs",
 289         "uses genfs_contexts",
 290         "not configured for labeling",
 291         "uses mountpoint labeling",
 292 };
 293
 294 static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dentry);
 295
 296 static inline int inode_doinit(struct inode *inode)
 297 {
 298         return inode_doinit_with_dentry(inode, NULL);
 299 }
 300
 301 enum {
 302         Opt_error = -1,
 303         Opt_context = 1,
 304         Opt_fscontext = 2,
 305         Opt_defcontext = 3,
 306         Opt_rootcontext = 4,
 307         Opt_labelsupport = 5,
 308 };
 309
 310 static const match_table_t tokens = {
 311         {Opt_context, CONTEXT_STR "%s"},
 312         {Opt_fscontext, FSCONTEXT_STR "%s"},
 313         {Opt_defcontext, DEFCONTEXT_STR "%s"},
 314         {Opt_rootcontext, ROOTCONTEXT_STR "%s"},
 315         {Opt_labelsupport, LABELSUPP_STR},
 316         {Opt_error, NULL},
 317 };
 318
 319 #define SEL_MOUNT_FAIL_MSG "SELinux:  duplicate or incompatible mount options\n"
 320
 321 static int may_context_mount_sb_relabel(u32 sid,
 322                         struct superblock_security_struct *sbsec,
 323                         const struct cred *cred)
 324 {
 325         const struct task_security_struct *tsec = cred->security;
 326         int rc;
 327
 328         rc = avc_has_perm(tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM,
 329                           FILESYSTEM__RELABELFROM, NULL);
 330         if (rc)
 331                 return rc;
 332
 333         rc = avc_has_perm(tsec->sid, sid, SECCLASS_FILESYSTEM,
 334                           FILESYSTEM__RELABELTO, NULL);
 335         return rc;
 336 }
 337
 338 static int may_context_mount_inode_relabel(u32 sid,
 339                         struct superblock_security_struct *sbsec,
 340                         const struct cred *cred)
 341 {
 342         const struct task_security_struct *tsec = cred->security;
 343         int rc;
 344         rc = avc_has_perm(tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM,
 345                           FILESYSTEM__RELABELFROM, NULL);
 346         if (rc)
 347                 return rc;
 348
 349         rc = avc_has_perm(sid, sbsec->sid, SECCLASS_FILESYSTEM,
 350                           FILESYSTEM__ASSOCIATE, NULL);
 351         return rc;
 352 }
 353
 354 static int sb_finish_set_opts(struct super_block *sb)
 355 {
 356         struct superblock_security_struct *sbsec = sb->s_security;
 357         struct dentry *root = sb->s_root;
 358         struct inode *root_inode = root->d_inode;
 359         int rc = 0;
 360
 361         if (sbsec->behavior == SECURITY_FS_USE_XATTR) {
 362                 /* Make sure that the xattr handler exists and that no
 363                    error other than -ENODATA is returned by getxattr on
 364                    the root directory.  -ENODATA is ok, as this may be
 365                    the first boot of the SELinux kernel before we have
 366                    assigned xattr values to the filesystem. */
 367                 if (!root_inode->i_op->getxattr) {
 368                         printk(KERN_WARNING "SELinux: (dev %s, type %s) has no "
 369                                "xattr support\n", sb->s_id, sb->s_type->name);
 370                         rc = -EOPNOTSUPP;
 371                         goto out;
 372                 }
 373                 rc = root_inode->i_op->getxattr(root, XATTR_NAME_SELINUX, NULL, 0);
 374                 if (rc < 0 && rc != -ENODATA) {
 375                         if (rc == -EOPNOTSUPP)
 376                                 printk(KERN_WARNING "SELinux: (dev %s, type "
 377                                        "%s) has no security xattr handler\n",
 378                                        sb->s_id, sb->s_type->name);
 379                         else
 380                                 printk(KERN_WARNING "SELinux: (dev %s, type "
 381                                        "%s) getxattr errno %d\n", sb->s_id,
 382                                        sb->s_type->name, -rc);
 383                         goto out;
 384                 }
 385         }
 386
 387         sbsec->flags |= (SE_SBINITIALIZED | SE_SBLABELSUPP);
 388
 389         if (sbsec->behavior > ARRAY_SIZE(labeling_behaviors))
 390                 printk(KERN_ERR "SELinux: initialized (dev %s, type %s), unknown behavior\n",
 391                        sb->s_id, sb->s_type->name);
 392         else
 393                 printk(KERN_DEBUG "SELinux: initialized (dev %s, type %s), %s\n",
 394                        sb->s_id, sb->s_type->name,
 395                        labeling_behaviors[sbsec->behavior-1]);
 396
 397         if (sbsec->behavior == SECURITY_FS_USE_GENFS ||
 398             sbsec->behavior == SECURITY_FS_USE_MNTPOINT ||
 399             sbsec->behavior == SECURITY_FS_USE_NONE ||
 400             sbsec->behavior > ARRAY_SIZE(labeling_behaviors))
 401                 sbsec->flags &= ~SE_SBLABELSUPP;
 402
 403         /* Special handling for sysfs. Is genfs but also has setxattr handler*/
 404         if (strncmp(sb->s_type->name, "sysfs", sizeof("sysfs")) == 0)
 405                 sbsec->flags |= SE_SBLABELSUPP;
 406
 407         /* Initialize the root inode. */
 408         rc = inode_doinit_with_dentry(root_inode, root);
 409
 410         /* Initialize any other inodes associated with the superblock, e.g.
 411            inodes created prior to initial policy load or inodes created
 412            during get_sb by a pseudo filesystem that directly
 413            populates itself. */
 414         spin_lock(&sbsec->isec_lock);
 415 next_inode:
 416         if (!list_empty(&sbsec->isec_head)) {
 417                 struct inode_security_struct *isec =
 418                                 list_entry(sbsec->isec_head.next,
 419                                            struct inode_security_struct, list);
 420                 struct inode *inode = isec->inode;
 421                 spin_unlock(&sbsec->isec_lock);
 422                 inode = igrab(inode);
 423                 if (inode) {
 424                         if (!IS_PRIVATE(inode))
 425                                 inode_doinit(inode);
 426                         iput(inode);
 427                 }
 428                 spin_lock(&sbsec->isec_lock);
 429                 list_del_init(&isec->list);
 430                 goto next_inode;
 431         }
 432         spin_unlock(&sbsec->isec_lock);
 433 out:
 434         return rc;
 435 }
 436
 437 /*
 438  * This function should allow an FS to ask what it's mount security
 439  * options were so it can use those later for submounts, displaying
 440  * mount options, or whatever.
 441  */
 442 static int selinux_get_mnt_opts(const struct super_block *sb,
 443                                 struct security_mnt_opts *opts)
 444 {
 445         int rc = 0, i;
 446         struct superblock_security_struct *sbsec = sb->s_security;
 447         char *context = NULL;
 448         u32 len;
 449         char tmp;
 450
 451         security_init_mnt_opts(opts);
 452
 453         if (!(sbsec->flags & SE_SBINITIALIZED))
 454                 return -EINVAL;
 455
 456         if (!ss_initialized)
 457                 return -EINVAL;
 458
 459         tmp = sbsec->flags & SE_MNTMASK;
 460         /* count the number of mount options for this sb */
 461         for (i = 0; i < 8; i++) {
 462                 if (tmp & 0x01)
 463                         opts->num_mnt_opts++;
 464                 tmp >>= 1;
 465         }
 466         /* Check if the Label support flag is set */
 467         if (sbsec->flags & SE_SBLABELSUPP)
 468                 opts->num_mnt_opts++;
 469
 470         opts->mnt_opts = kcalloc(opts->num_mnt_opts, sizeof(char *), GFP_ATOMIC);
 471         if (!opts->mnt_opts) {
 472                 rc = -ENOMEM;
 473                 goto out_free;
 474         }
 475
 476         opts->mnt_opts_flags = kcalloc(opts->num_mnt_opts, sizeof(int), GFP_ATOMIC);
 477         if (!opts->mnt_opts_flags) {
 478                 rc = -ENOMEM;
 479                 goto out_free;
 480         }
 481
 482         i = 0;
 483         if (sbsec->flags & FSCONTEXT_MNT) {
 484                 rc = security_sid_to_context(sbsec->sid, &context, &len);
 485                 if (rc)
 486                         goto out_free;
 487                 opts->mnt_opts[i] = context;
 488                 opts->mnt_opts_flags[i++] = FSCONTEXT_MNT;
 489         }
 490         if (sbsec->flags & CONTEXT_MNT) {
 491                 rc = security_sid_to_context(sbsec->mntpoint_sid, &context, &len);
 492                 if (rc)
 493                         goto out_free;
 494                 opts->mnt_opts[i] = context;
 495                 opts->mnt_opts_flags[i++] = CONTEXT_MNT;
 496         }
 497         if (sbsec->flags & DEFCONTEXT_MNT) {
 498                 rc = security_sid_to_context(sbsec->def_sid, &context, &len);
 499                 if (rc)
 500                         goto out_free;
 501                 opts->mnt_opts[i] = context;
 502                 opts->mnt_opts_flags[i++] = DEFCONTEXT_MNT;
 503         }
 504         if (sbsec->flags & ROOTCONTEXT_MNT) {
 505                 struct inode *root = sbsec->sb->s_root->d_inode;
 506                 struct inode_security_struct *isec = root->i_security;
 507
 508                 rc = security_sid_to_context(isec->sid, &context, &len);
 509                 if (rc)
 510                         goto out_free;
 511                 opts->mnt_opts[i] = context;
 512                 opts->mnt_opts_flags[i++] = ROOTCONTEXT_MNT;
 513         }
 514         if (sbsec->flags & SE_SBLABELSUPP) {
 515                 opts->mnt_opts[i] = NULL;
 516                 opts->mnt_opts_flags[i++] = SE_SBLABELSUPP;
 517         }
 518
 519         BUG_ON(i != opts->num_mnt_opts);
 520
 521         return 0;
 522
 523 out_free:
 524         security_free_mnt_opts(opts);
 525         return rc;
 526 }
 527
 528 static int bad_option(struct superblock_security_struct *sbsec, char flag,
 529                       u32 old_sid, u32 new_sid)
 530 {
 531         char mnt_flags = sbsec->flags & SE_MNTMASK;
 532
 533         /* check if the old mount command had the same options */
 534         if (sbsec->flags & SE_SBINITIALIZED)
 535                 if (!(sbsec->flags & flag) ||
 536                     (old_sid != new_sid))
 537                         return 1;
 538
 539         /* check if we were passed the same options twice,
 540          * aka someone passed context=a,context=b
 541          */
 542         if (!(sbsec->flags & SE_SBINITIALIZED))
 543                 if (mnt_flags & flag)
 544                         return 1;
 545         return 0;
 546 }
 547
 548 /*
 549  * Allow filesystems with binary mount data to explicitly set mount point
 550  * labeling information.
 551  */
 552 static int selinux_set_mnt_opts(struct super_block *sb,
 553                                 struct security_mnt_opts *opts)
 554 {
 555         const struct cred *cred = current_cred();
 556         int rc = 0, i;
 557         struct superblock_security_struct *sbsec = sb->s_security;
 558         const char *name = sb->s_type->name;
 559         struct inode *inode = sbsec->sb->s_root->d_inode;
 560         struct inode_security_struct *root_isec = inode->i_security;
 561         u32 fscontext_sid = 0, context_sid = 0, rootcontext_sid = 0;
 562         u32 defcontext_sid = 0;
 563         char **mount_options = opts->mnt_opts;
 564         int *flags = opts->mnt_opts_flags;
 565         int num_opts = opts->num_mnt_opts;
 566
 567         mutex_lock(&sbsec->lock);
 568
 569         if (!ss_initialized) {
 570                 if (!num_opts) {
 571                         /* Defer initialization until selinux_complete_init,
 572                            after the initial policy is loaded and the security
 573                            server is ready to handle calls. */
 574                         goto out;
 575                 }
 576                 rc = -EINVAL;
 577                 printk(KERN_WARNING "SELinux: Unable to set superblock options "
 578                         "before the security server is initialized\n");
 579                 goto out;
 580         }
 581
 582         /*
 583          * Binary mount data FS will come through this function twice.  Once
 584          * from an explicit call and once from the generic calls from the vfs.
 585          * Since the generic VFS calls will not contain any security mount data
 586          * we need to skip the double mount verification.
 587          *
 588          * This does open a hole in which we will not notice if the first
 589          * mount using this sb set explict options and a second mount using
 590          * this sb does not set any security options.  (The first options
 591          * will be used for both mounts)
 592          */
 593         if ((sbsec->flags & SE_SBINITIALIZED) && (sb->s_type->fs_flags & FS_BINARY_MOUNTDATA)
 594             && (num_opts == 0))
 595                 goto out;
 596
 597         /*
 598          * parse the mount options, check if they are valid sids.
 599          * also check if someone is trying to mount the same sb more
 600          * than once with different security options.
 601          */
 602         for (i = 0; i < num_opts; i++) {
 603                 u32 sid;
 604
 605                 if (flags[i] == SE_SBLABELSUPP)
 606                         continue;
 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->flags & SE_SBINITIALIZED) {
 661                 /* previously mounted with options, but not on this attempt? */
 662                 if ((sbsec->flags & SE_MNTMASK) && !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->flags |= SE_SBPROC;
 670
 671         /* Determine the labeling behavior to use for this filesystem type. */
 672         rc = security_fs_use((sbsec->flags & SE_SBPROC) ? "proc" : 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                 rc = may_context_mount_sb_relabel(fscontext_sid, sbsec, cred);
 682                 if (rc)
 683                         goto out;
 684
 685                 sbsec->sid = fscontext_sid;
 686         }
 687
 688         /*
 689          * Switch to using mount point labeling behavior.
 690          * sets the label used on all file below the mountpoint, and will set
 691          * the superblock context if not already set.
 692          */
 693         if (context_sid) {
 694                 if (!fscontext_sid) {
 695                         rc = may_context_mount_sb_relabel(context_sid, sbsec,
 696                                                           cred);
 697                         if (rc)
 698                                 goto out;
 699                         sbsec->sid = context_sid;
 700                 } else {
 701                         rc = may_context_mount_inode_relabel(context_sid, sbsec,
 702                                                              cred);
 703                         if (rc)
 704                                 goto out;
 705                 }
 706                 if (!rootcontext_sid)
 707                         rootcontext_sid = context_sid;
 708
 709                 sbsec->mntpoint_sid = context_sid;
 710                 sbsec->behavior = SECURITY_FS_USE_MNTPOINT;
 711         }
 712
 713         if (rootcontext_sid) {
 714                 rc = may_context_mount_inode_relabel(rootcontext_sid, sbsec,
 715                                                      cred);
 716                 if (rc)
 717                         goto out;
 718
 719                 root_isec->sid = rootcontext_sid;
 720                 root_isec->initialized = 1;
 721         }
 722
 723         if (defcontext_sid) {
 724                 if (sbsec->behavior != SECURITY_FS_USE_XATTR) {
 725                         rc = -EINVAL;
 726                         printk(KERN_WARNING "SELinux: defcontext option is "
 727                                "invalid for this filesystem type\n");
 728                         goto out;
 729                 }
 730
 731                 if (defcontext_sid != sbsec->def_sid) {
 732                         rc = may_context_mount_inode_relabel(defcontext_sid,
 733                                                              sbsec, cred);
 734                         if (rc)
 735                                 goto out;
 736                 }
 737
 738                 sbsec->def_sid = defcontext_sid;
 739         }
 740
 741         rc = sb_finish_set_opts(sb);
 742 out:
 743         mutex_unlock(&sbsec->lock);
 744         return rc;
 745 out_double_mount:
 746         rc = -EINVAL;
 747         printk(KERN_WARNING "SELinux: mount invalid.  Same superblock, different "
 748                "security settings for (dev %s, type %s)\n", sb->s_id, name);
 749         goto out;
 750 }
 751
 752 static void selinux_sb_clone_mnt_opts(const struct super_block *oldsb,
 753                                         struct super_block *newsb)
 754 {
 755         const struct superblock_security_struct *oldsbsec = oldsb->s_security;
 756         struct superblock_security_struct *newsbsec = newsb->s_security;
 757
 758         int set_fscontext =     (oldsbsec->flags & FSCONTEXT_MNT);
 759         int set_context =       (oldsbsec->flags & CONTEXT_MNT);
 760         int set_rootcontext =   (oldsbsec->flags & ROOTCONTEXT_MNT);
 761
 762         /*
 763          * if the parent was able to be mounted it clearly had no special lsm
 764          * mount options.  thus we can safely deal with this superblock later
 765          */
 766         if (!ss_initialized)
 767                 return;
 768
 769         /* how can we clone if the old one wasn't set up?? */
 770         BUG_ON(!(oldsbsec->flags & SE_SBINITIALIZED));
 771
 772         /* if fs is reusing a sb, just let its options stand... */
 773         if (newsbsec->flags & SE_SBINITIALIZED)
 774                 return;
 775
 776         mutex_lock(&newsbsec->lock);
 777
 778         newsbsec->flags = oldsbsec->flags;
 779
 780         newsbsec->sid = oldsbsec->sid;
 781         newsbsec->def_sid = oldsbsec->def_sid;
 782         newsbsec->behavior = oldsbsec->behavior;
 783
 784         if (set_context) {
 785                 u32 sid = oldsbsec->mntpoint_sid;
 786
 787                 if (!set_fscontext)
 788                         newsbsec->sid = sid;
 789                 if (!set_rootcontext) {
 790                         struct inode *newinode = newsb->s_root->d_inode;
 791                         struct inode_security_struct *newisec = newinode->i_security;
 792                         newisec->sid = sid;
 793                 }
 794                 newsbsec->mntpoint_sid = sid;
 795         }
 796         if (set_rootcontext) {
 797                 const struct inode *oldinode = oldsb->s_root->d_inode;
 798                 const struct inode_security_struct *oldisec = oldinode->i_security;
 799                 struct inode *newinode = newsb->s_root->d_inode;
 800                 struct inode_security_struct *newisec = newinode->i_security;
 801
 802                 newisec->sid = oldisec->sid;
 803         }
 804
 805         sb_finish_set_opts(newsb);
 806         mutex_unlock(&newsbsec->lock);
 807 }
 808
 809 static int selinux_parse_opts_str(char *options,
 810                                   struct security_mnt_opts *opts)
 811 {
 812         char *p;
 813         char *context = NULL, *defcontext = NULL;
 814         char *fscontext = NULL, *rootcontext = NULL;
 815         int rc, num_mnt_opts = 0;
 816
 817         opts->num_mnt_opts = 0;
 818
 819         /* Standard string-based options. */
 820         while ((p = strsep(&options, "|")) != NULL) {
 821                 int token;
 822                 substring_t args[MAX_OPT_ARGS];
 823
 824                 if (!*p)
 825                         continue;
 826
 827                 token = match_token(p, tokens, args);
 828
 829                 switch (token) {
 830                 case Opt_context:
 831                         if (context || defcontext) {
 832                                 rc = -EINVAL;
 833                                 printk(KERN_WARNING SEL_MOUNT_FAIL_MSG);
 834                                 goto out_err;
 835                         }
 836                         context = match_strdup(&args[0]);
 837                         if (!context) {
 838                                 rc = -ENOMEM;
 839                                 goto out_err;
 840                         }
 841                         break;
 842
 843                 case Opt_fscontext:
 844                         if (fscontext) {
 845                                 rc = -EINVAL;
 846                                 printk(KERN_WARNING SEL_MOUNT_FAIL_MSG);
 847                                 goto out_err;
 848                         }
 849                         fscontext = match_strdup(&args[0]);
 850                         if (!fscontext) {
 851                                 rc = -ENOMEM;
 852                                 goto out_err;
 853                         }
 854                         break;
 855
 856                 case Opt_rootcontext:
 857                         if (rootcontext) {
 858                                 rc = -EINVAL;
 859                                 printk(KERN_WARNING SEL_MOUNT_FAIL_MSG);
 860                                 goto out_err;
 861                         }
 862                         rootcontext = match_strdup(&args[0]);
 863                         if (!rootcontext) {
 864                                 rc = -ENOMEM;
 865                                 goto out_err;
 866                         }
 867                         break;
 868
 869                 case Opt_defcontext:
 870                         if (context || defcontext) {
 871                                 rc = -EINVAL;
 872                                 printk(KERN_WARNING SEL_MOUNT_FAIL_MSG);
 873                                 goto out_err;
 874                         }
 875                         defcontext = match_strdup(&args[0]);
 876                         if (!defcontext) {
 877                                 rc = -ENOMEM;
 878                                 goto out_err;
 879                         }
 880                         break;
 881                 case Opt_labelsupport:
 882                         break;
 883                 default:
 884                         rc = -EINVAL;
 885                         printk(KERN_WARNING "SELinux:  unknown mount option\n");
 886                         goto out_err;
 887
 888                 }
 889         }
 890
 891         rc = -ENOMEM;
 892         opts->mnt_opts = kcalloc(NUM_SEL_MNT_OPTS, sizeof(char *), GFP_ATOMIC);
 893         if (!opts->mnt_opts)
 894                 goto out_err;
 895
 896         opts->mnt_opts_flags = kcalloc(NUM_SEL_MNT_OPTS, sizeof(int), GFP_ATOMIC);
 897         if (!opts->mnt_opts_flags) {
 898                 kfree(opts->mnt_opts);
 899                 goto out_err;
 900         }
 901
 902         if (fscontext) {
 903                 opts->mnt_opts[num_mnt_opts] = fscontext;
 904                 opts->mnt_opts_flags[num_mnt_opts++] = FSCONTEXT_MNT;
 905         }
 906         if (context) {
 907                 opts->mnt_opts[num_mnt_opts] = context;
 908                 opts->mnt_opts_flags[num_mnt_opts++] = CONTEXT_MNT;
 909         }
 910         if (rootcontext) {
 911                 opts->mnt_opts[num_mnt_opts] = rootcontext;
 912                 opts->mnt_opts_flags[num_mnt_opts++] = ROOTCONTEXT_MNT;
 913         }
 914         if (defcontext) {
 915                 opts->mnt_opts[num_mnt_opts] = defcontext;
 916                 opts->mnt_opts_flags[num_mnt_opts++] = DEFCONTEXT_MNT;
 917         }
 918
 919         opts->num_mnt_opts = num_mnt_opts;
 920         return 0;
 921
 922 out_err:
 923         kfree(context);
 924         kfree(defcontext);
 925         kfree(fscontext);
 926         kfree(rootcontext);
 927         return rc;
 928 }
 929 /*
 930  * string mount options parsing and call set the sbsec
 931  */
 932 static int superblock_doinit(struct super_block *sb, void *data)
 933 {
 934         int rc = 0;
 935         char *options = data;
 936         struct security_mnt_opts opts;
 937
 938         security_init_mnt_opts(&opts);
 939
 940         if (!data)
 941                 goto out;
 942
 943         BUG_ON(sb->s_type->fs_flags & FS_BINARY_MOUNTDATA);
 944
 945         rc = selinux_parse_opts_str(options, &opts);
 946         if (rc)
 947                 goto out_err;
 948
 949 out:
 950         rc = selinux_set_mnt_opts(sb, &opts);
 951
 952 out_err:
 953         security_free_mnt_opts(&opts);
 954         return rc;
 955 }
 956
 957 static void selinux_write_opts(struct seq_file *m,
 958                                struct security_mnt_opts *opts)
 959 {
 960         int i;
 961         char *prefix;
 962
 963         for (i = 0; i < opts->num_mnt_opts; i++) {
 964                 char *has_comma;
 965
 966                 if (opts->mnt_opts[i])
 967                         has_comma = strchr(opts->mnt_opts[i], ',');
 968                 else
 969                         has_comma = NULL;
 970
 971                 switch (opts->mnt_opts_flags[i]) {
 972                 case CONTEXT_MNT:
 973                         prefix = CONTEXT_STR;
 974                         break;
 975                 case FSCONTEXT_MNT:
 976                         prefix = FSCONTEXT_STR;
 977                         break;
 978                 case ROOTCONTEXT_MNT:
 979                         prefix = ROOTCONTEXT_STR;
 980                         break;
 981                 case DEFCONTEXT_MNT:
 982                         prefix = DEFCONTEXT_STR;
 983                         break;
 984                 case SE_SBLABELSUPP:
 985                         seq_putc(m, ',');
 986                         seq_puts(m, LABELSUPP_STR);
 987                         continue;
 988                 default:
 989                         BUG();
 990                 };
 991                 /* we need a comma before each option */
 992                 seq_putc(m, ',');
 993                 seq_puts(m, prefix);
 994                 if (has_comma)
 995                         seq_putc(m, '\"');
 996                 seq_puts(m, opts->mnt_opts[i]);
 997                 if (has_comma)
 998                         seq_putc(m, '\"');
 999         }
1000 }
1001
1002 static int selinux_sb_show_options(struct seq_file *m, struct super_block *sb)
1003 {
1004         struct security_mnt_opts opts;
1005         int rc;
1006
1007         rc = selinux_get_mnt_opts(sb, &opts);
1008         if (rc) {
1009                 /* before policy load we may get EINVAL, don't show anything */
1010                 if (rc == -EINVAL)
1011                         rc = 0;
1012                 return rc;
1013         }
1014
1015         selinux_write_opts(m, &opts);
1016
1017         security_free_mnt_opts(&opts);
1018
1019         return rc;
1020 }
1021
1022 static inline u16 inode_mode_to_security_class(umode_t mode)
1023 {
1024         switch (mode & S_IFMT) {
1025         case S_IFSOCK:
1026                 return SECCLASS_SOCK_FILE;
1027         case S_IFLNK:
1028                 return SECCLASS_LNK_FILE;
1029         case S_IFREG:
1030                 return SECCLASS_FILE;
1031         case S_IFBLK:
1032                 return SECCLASS_BLK_FILE;
1033         case S_IFDIR:
1034                 return SECCLASS_DIR;
1035         case S_IFCHR:
1036                 return SECCLASS_CHR_FILE;
1037         case S_IFIFO:
1038                 return SECCLASS_FIFO_FILE;
1039
1040         }
1041
1042         return SECCLASS_FILE;
1043 }
1044
1045 static inline int default_protocol_stream(int protocol)
1046 {
1047         return (protocol == IPPROTO_IP || protocol == IPPROTO_TCP);
1048 }
1049
1050 static inline int default_protocol_dgram(int protocol)
1051 {
1052         return (protocol == IPPROTO_IP || protocol == IPPROTO_UDP);
1053 }
1054
1055 static inline u16 socket_type_to_security_class(int family, int type, int protocol)
1056 {
1057         switch (family) {
1058         case PF_UNIX:
1059                 switch (type) {
1060                 case SOCK_STREAM:
1061                 case SOCK_SEQPACKET:
1062                         return SECCLASS_UNIX_STREAM_SOCKET;
1063                 case SOCK_DGRAM:
1064                         return SECCLASS_UNIX_DGRAM_SOCKET;
1065                 }
1066                 break;
1067         case PF_INET:
1068         case PF_INET6:
1069                 switch (type) {
1070                 case SOCK_STREAM:
1071                         if (default_protocol_stream(protocol))
1072                                 return SECCLASS_TCP_SOCKET;
1073                         else
1074                                 return SECCLASS_RAWIP_SOCKET;
1075                 case SOCK_DGRAM:
1076                         if (default_protocol_dgram(protocol))
1077                                 return SECCLASS_UDP_SOCKET;
1078                         else
1079                                 return SECCLASS_RAWIP_SOCKET;
1080                 case SOCK_DCCP:
1081                         return SECCLASS_DCCP_SOCKET;
1082                 default:
1083                         return SECCLASS_RAWIP_SOCKET;
1084                 }
1085                 break;
1086         case PF_NETLINK:
1087                 switch (protocol) {
1088                 case NETLINK_ROUTE:
1089                         return SECCLASS_NETLINK_ROUTE_SOCKET;
1090                 case NETLINK_FIREWALL:
1091                         return SECCLASS_NETLINK_FIREWALL_SOCKET;
1092                 case NETLINK_INET_DIAG:
1093                         return SECCLASS_NETLINK_TCPDIAG_SOCKET;
1094                 case NETLINK_NFLOG:
1095                         return SECCLASS_NETLINK_NFLOG_SOCKET;
1096                 case NETLINK_XFRM:
1097                         return SECCLASS_NETLINK_XFRM_SOCKET;
1098                 case NETLINK_SELINUX:
1099                         return SECCLASS_NETLINK_SELINUX_SOCKET;
1100                 case NETLINK_AUDIT:
1101                         return SECCLASS_NETLINK_AUDIT_SOCKET;
1102                 case NETLINK_IP6_FW:
1103                         return SECCLASS_NETLINK_IP6FW_SOCKET;
1104                 case NETLINK_DNRTMSG:
1105                         return SECCLASS_NETLINK_DNRT_SOCKET;
1106                 case NETLINK_KOBJECT_UEVENT:
1107                         return SECCLASS_NETLINK_KOBJECT_UEVENT_SOCKET;
1108                 default:
1109                         return SECCLASS_NETLINK_SOCKET;
1110                 }
1111         case PF_PACKET:
1112                 return SECCLASS_PACKET_SOCKET;
1113         case PF_KEY:
1114                 return SECCLASS_KEY_SOCKET;
1115         case PF_APPLETALK:
1116                 return SECCLASS_APPLETALK_SOCKET;
1117         }
1118
1119         return SECCLASS_SOCKET;
1120 }
1121
1122 #ifdef CONFIG_PROC_FS
1123 static int selinux_proc_get_sid(struct proc_dir_entry *de,
1124                                 u16 tclass,
1125                                 u32 *sid)
1126 {
1127         int buflen, rc;
1128         char *buffer, *path, *end;
1129
1130         buffer = (char *)__get_free_page(GFP_KERNEL);
1131         if (!buffer)
1132                 return -ENOMEM;
1133
1134         buflen = PAGE_SIZE;
1135         end = buffer+buflen;
1136         *--end = '\0';
1137         buflen--;
1138         path = end-1;
1139         *path = '/';
1140         while (de && de != de->parent) {
1141                 buflen -= de->namelen + 1;
1142                 if (buflen < 0)
1143                         break;
1144                 end -= de->namelen;
1145                 memcpy(end, de->name, de->namelen);
1146                 *--end = '/';
1147                 path = end;
1148                 de = de->parent;
1149         }
1150         rc = security_genfs_sid("proc", path, tclass, sid);
1151         free_page((unsigned long)buffer);
1152         return rc;
1153 }
1154 #else
1155 static int selinux_proc_get_sid(struct proc_dir_entry *de,
1156                                 u16 tclass,
1157                                 u32 *sid)
1158 {
1159         return -EINVAL;
1160 }
1161 #endif
1162
1163 /* The inode's security attributes must be initialized before first use. */
1164 static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dentry)
1165 {
1166         struct superblock_security_struct *sbsec = NULL;
1167         struct inode_security_struct *isec = inode->i_security;
1168         u32 sid;
1169         struct dentry *dentry;
1170 #define INITCONTEXTLEN 255
1171         char *context = NULL;
1172         unsigned len = 0;
1173         int rc = 0;
1174
1175         if (isec->initialized)
1176                 goto out;
1177
1178         mutex_lock(&isec->lock);
1179         if (isec->initialized)
1180                 goto out_unlock;
1181
1182         sbsec = inode->i_sb->s_security;
1183         if (!(sbsec->flags & SE_SBINITIALIZED)) {
1184                 /* Defer initialization until selinux_complete_init,
1185                    after the initial policy is loaded and the security
1186                    server is ready to handle calls. */
1187                 spin_lock(&sbsec->isec_lock);
1188                 if (list_empty(&isec->list))
1189                         list_add(&isec->list, &sbsec->isec_head);
1190                 spin_unlock(&sbsec->isec_lock);
1191                 goto out_unlock;
1192         }
1193
1194         switch (sbsec->behavior) {
1195         case SECURITY_FS_USE_XATTR:
1196                 if (!inode->i_op->getxattr) {
1197                         isec->sid = sbsec->def_sid;
1198                         break;
1199                 }
1200
1201                 /* Need a dentry, since the xattr API requires one.
1202                    Life would be simpler if we could just pass the inode. */
1203                 if (opt_dentry) {
1204                         /* Called from d_instantiate or d_splice_alias. */
1205                         dentry = dget(opt_dentry);
1206                 } else {
1207                         /* Called from selinux_complete_init, try to find a dentry. */
1208                         dentry = d_find_alias(inode);
1209                 }
1210                 if (!dentry) {
1211                         /*
1212                          * this is can be hit on boot when a file is accessed
1213                          * before the policy is loaded.  When we load policy we
1214                          * may find inodes that have no dentry on the
1215                          * sbsec->isec_head list.  No reason to complain as these
1216                          * will get fixed up the next time we go through
1217                          * inode_doinit with a dentry, before these inodes could
1218                          * be used again by userspace.
1219                          */
1220                         goto out_unlock;
1221                 }
1222
1223                 len = INITCONTEXTLEN;
1224                 context = kmalloc(len+1, GFP_NOFS);
1225                 if (!context) {
1226                         rc = -ENOMEM;
1227                         dput(dentry);
1228                         goto out_unlock;
1229                 }
1230                 context[len] = '\0';
1231                 rc = inode->i_op->getxattr(dentry, XATTR_NAME_SELINUX,
1232                                            context, len);
1233                 if (rc == -ERANGE) {
1234                         kfree(context);
1235
1236                         /* Need a larger buffer.  Query for the right size. */
1237                         rc = inode->i_op->getxattr(dentry, XATTR_NAME_SELINUX,
1238                                                    NULL, 0);
1239                         if (rc < 0) {
1240                                 dput(dentry);
1241                                 goto out_unlock;
1242                         }
1243                         len = rc;
1244                         context = kmalloc(len+1, GFP_NOFS);
1245                         if (!context) {
1246                                 rc = -ENOMEM;
1247                                 dput(dentry);
1248                                 goto out_unlock;
1249                         }
1250                         context[len] = '\0';
1251                         rc = inode->i_op->getxattr(dentry,
1252                                                    XATTR_NAME_SELINUX,
1253                                                    context, len);
1254                 }
1255                 dput(dentry);
1256                 if (rc < 0) {
1257                         if (rc != -ENODATA) {
1258                                 printk(KERN_WARNING "SELinux: %s:  getxattr returned "
1259                                        "%d for dev=%s ino=%ld\n", __func__,
1260                                        -rc, inode->i_sb->s_id, inode->i_ino);
1261                                 kfree(context);
1262                                 goto out_unlock;
1263                         }
1264                         /* Map ENODATA to the default file SID */
1265                         sid = sbsec->def_sid;
1266                         rc = 0;
1267                 } else {
1268                         rc = security_context_to_sid_default(context, rc, &sid,
1269                                                              sbsec->def_sid,
1270                                                              GFP_NOFS);
1271                         if (rc) {
1272                                 char *dev = inode->i_sb->s_id;
1273                                 unsigned long ino = inode->i_ino;
1274
1275                                 if (rc == -EINVAL) {
1276                                         if (printk_ratelimit())
1277                                                 printk(KERN_NOTICE "SELinux: inode=%lu on dev=%s was found to have an invalid "
1278                                                         "context=%s.  This indicates you may need to relabel the inode or the "
1279                                                         "filesystem in question.\n", ino, dev, context);
1280                                 } else {
1281                                         printk(KERN_WARNING "SELinux: %s:  context_to_sid(%s) "
1282                                                "returned %d for dev=%s ino=%ld\n",
1283                                                __func__, context, -rc, dev, ino);
1284                                 }
1285                                 kfree(context);
1286                                 /* Leave with the unlabeled SID */
1287                                 rc = 0;
1288                                 break;
1289                         }
1290                 }
1291                 kfree(context);
1292                 isec->sid = sid;
1293                 break;
1294         case SECURITY_FS_USE_TASK:
1295                 isec->sid = isec->task_sid;
1296                 break;
1297         case SECURITY_FS_USE_TRANS:
1298                 /* Default to the fs SID. */
1299                 isec->sid = sbsec->sid;
1300
1301                 /* Try to obtain a transition SID. */
1302                 isec->sclass = inode_mode_to_security_class(inode->i_mode);
1303                 rc = security_transition_sid(isec->task_sid,
1304                                              sbsec->sid,
1305                                              isec->sclass,
1306                                              &sid);
1307                 if (rc)
1308                         goto out_unlock;
1309                 isec->sid = sid;
1310                 break;
1311         case SECURITY_FS_USE_MNTPOINT:
1312                 isec->sid = sbsec->mntpoint_sid;
1313                 break;
1314         default:
1315                 /* Default to the fs superblock SID. */
1316                 isec->sid = sbsec->sid;
1317
1318                 if ((sbsec->flags & SE_SBPROC) && !S_ISLNK(inode->i_mode)) {
1319                         struct proc_inode *proci = PROC_I(inode);
1320                         if (proci->pde) {
1321                                 isec->sclass = inode_mode_to_security_class(inode->i_mode);
1322                                 rc = selinux_proc_get_sid(proci->pde,
1323                                                           isec->sclass,
1324                                                           &sid);
1325                                 if (rc)
1326                                         goto out_unlock;
1327                                 isec->sid = sid;
1328                         }
1329                 }
1330                 break;
1331         }
1332
1333         isec->initialized = 1;
1334
1335 out_unlock:
1336         mutex_unlock(&isec->lock);
1337 out:
1338         if (isec->sclass == SECCLASS_FILE)
1339                 isec->sclass = inode_mode_to_security_class(inode->i_mode);
1340         return rc;
1341 }
1342
1343 /* Convert a Linux signal to an access vector. */
1344 static inline u32 signal_to_av(int sig)
1345 {
1346         u32 perm = 0;
1347
1348         switch (sig) {
1349         case SIGCHLD:
1350                 /* Commonly granted from child to parent. */
1351                 perm = PROCESS__SIGCHLD;
1352                 break;
1353         case SIGKILL:
1354                 /* Cannot be caught or ignored */
1355                 perm = PROCESS__SIGKILL;
1356                 break;
1357         case SIGSTOP:
1358                 /* Cannot be caught or ignored */
1359                 perm = PROCESS__SIGSTOP;
1360                 break;
1361         default:
1362                 /* All other signals. */
1363                 perm = PROCESS__SIGNAL;
1364                 break;
1365         }
1366
1367         return perm;
1368 }
1369
1370 /*
1371  * Check permission between a pair of credentials
1372  * fork check, ptrace check, etc.
1373  */
1374 static int cred_has_perm(const struct cred *actor,
1375                          const struct cred *target,
1376                          u32 perms)
1377 {
1378         u32 asid = cred_sid(actor), tsid = cred_sid(target);
1379
1380         return avc_has_perm(asid, tsid, SECCLASS_PROCESS, perms, NULL);
1381 }
1382
1383 /*
1384  * Check permission between a pair of tasks, e.g. signal checks,
1385  * fork check, ptrace check, etc.
1386  * tsk1 is the actor and tsk2 is the target
1387  * - this uses the default subjective creds of tsk1
1388  */
1389 static int task_has_perm(const struct task_struct *tsk1,
1390                          const struct task_struct *tsk2,
1391                          u32 perms)
1392 {
1393         const struct task_security_struct *__tsec1, *__tsec2;
1394         u32 sid1, sid2;
1395
1396         rcu_read_lock();
1397         __tsec1 = __task_cred(tsk1)->security;  sid1 = __tsec1->sid;
1398         __tsec2 = __task_cred(tsk2)->security;  sid2 = __tsec2->sid;
1399         rcu_read_unlock();
1400         return avc_has_perm(sid1, sid2, SECCLASS_PROCESS, perms, NULL);
1401 }
1402
1403 /*
1404  * Check permission between current and another task, e.g. signal checks,
1405  * fork check, ptrace check, etc.
1406  * current is the actor and tsk2 is the target
1407  * - this uses current's subjective creds
1408  */
1409 static int current_has_perm(const struct task_struct *tsk,
1410                             u32 perms)
1411 {
1412         u32 sid, tsid;
1413
1414         sid = current_sid();
1415         tsid = task_sid(tsk);
1416         return avc_has_perm(sid, tsid, SECCLASS_PROCESS, perms, NULL);
1417 }
1418
1419 #if CAP_LAST_CAP > 63
1420 #error Fix SELinux to handle capabilities > 63.
1421 #endif
1422
1423 /* Check whether a task is allowed to use a capability. */
1424 static int task_has_capability(struct task_struct *tsk,
1425                                const struct cred *cred,
1426                                int cap, int audit)
1427 {
1428         struct common_audit_data ad;
1429         struct av_decision avd;
1430         u16 sclass;
1431         u32 sid = cred_sid(cred);
1432         u32 av = CAP_TO_MASK(cap);
1433         int rc;
1434
1435         COMMON_AUDIT_DATA_INIT(&ad, CAP);
1436         ad.tsk = tsk;
1437         ad.u.cap = cap;
1438
1439         switch (CAP_TO_INDEX(cap)) {
1440         case 0:
1441                 sclass = SECCLASS_CAPABILITY;
1442                 break;
1443         case 1:
1444                 sclass = SECCLASS_CAPABILITY2;
1445                 break;
1446         default:
1447                 printk(KERN_ERR
1448                        "SELinux:  out of range capability %d\n", cap);
1449                 BUG();
1450         }
1451
1452         rc = avc_has_perm_noaudit(sid, sid, sclass, av, 0, &avd);
1453         if (audit == SECURITY_CAP_AUDIT)
1454                 avc_audit(sid, sid, sclass, av, &avd, rc, &ad);
1455         return rc;
1456 }
1457
1458 /* Check whether a task is allowed to use a system operation. */
1459 static int task_has_system(struct task_struct *tsk,
1460                            u32 perms)
1461 {
1462         u32 sid = task_sid(tsk);
1463
1464         return avc_has_perm(sid, SECINITSID_KERNEL,
1465                             SECCLASS_SYSTEM, perms, NULL);
1466 }
1467
1468 /* Check whether a task has a particular permission to an inode.
1469    The 'adp' parameter is optional and allows other audit
1470    data to be passed (e.g. the dentry). */
1471 static int inode_has_perm(const struct cred *cred,
1472                           struct inode *inode,
1473                           u32 perms,
1474                           struct common_audit_data *adp)
1475 {
1476         struct inode_security_struct *isec;
1477         struct common_audit_data ad;
1478         u32 sid;
1479
1480         validate_creds(cred);
1481
1482         if (unlikely(IS_PRIVATE(inode)))
1483                 return 0;
1484
1485         sid = cred_sid(cred);
1486         isec = inode->i_security;
1487
1488         if (!adp) {
1489                 adp = &ad;
1490                 COMMON_AUDIT_DATA_INIT(&ad, FS);
1491                 ad.u.fs.inode = inode;
1492         }
1493
1494         return avc_has_perm(sid, isec->sid, isec->sclass, perms, adp);
1495 }
1496
1497 /* Same as inode_has_perm, but pass explicit audit data containing
1498    the dentry to help the auditing code to more easily generate the
1499    pathname if needed. */
1500 static inline int dentry_has_perm(const struct cred *cred,
1501                                   struct vfsmount *mnt,
1502                                   struct dentry *dentry,
1503                                   u32 av)
1504 {
1505         struct inode *inode = dentry->d_inode;
1506         struct common_audit_data ad;
1507
1508         COMMON_AUDIT_DATA_INIT(&ad, FS);
1509         ad.u.fs.path.mnt = mnt;
1510         ad.u.fs.path.dentry = dentry;
1511         return inode_has_perm(cred, inode, av, &ad);
1512 }
1513
1514 /* Check whether a task can use an open file descriptor to
1515    access an inode in a given way.  Check access to the
1516    descriptor itself, and then use dentry_has_perm to
1517    check a particular permission to the file.
1518    Access to the descriptor is implicitly granted if it
1519    has the same SID as the process.  If av is zero, then
1520    access to the file is not checked, e.g. for cases
1521    where only the descriptor is affected like seek. */
1522 static int file_has_perm(const struct cred *cred,
1523                          struct file *file,
1524                          u32 av)
1525 {
1526         struct file_security_struct *fsec = file->f_security;
1527         struct inode *inode = file->f_path.dentry->d_inode;
1528         struct common_audit_data ad;
1529         u32 sid = cred_sid(cred);
1530         int rc;
1531
1532         COMMON_AUDIT_DATA_INIT(&ad, FS);
1533         ad.u.fs.path = file->f_path;
1534
1535         if (sid != fsec->sid) {
1536                 rc = avc_has_perm(sid, fsec->sid,
1537                                   SECCLASS_FD,
1538                                   FD__USE,
1539                                   &ad);
1540                 if (rc)
1541                         goto out;
1542         }
1543
1544         /* av is zero if only checking access to the descriptor. */
1545         rc = 0;
1546         if (av)
1547                 rc = inode_has_perm(cred, inode, av, &ad);
1548
1549 out:
1550         return rc;
1551 }
1552
1553 /* Check whether a task can create a file. */
1554 static int may_create(struct inode *dir,
1555                       struct dentry *dentry,
1556                       u16 tclass)
1557 {
1558         const struct task_security_struct *tsec = current_security();
1559         struct inode_security_struct *dsec;
1560         struct superblock_security_struct *sbsec;
1561         u32 sid, newsid;
1562         struct common_audit_data ad;
1563         int rc;
1564
1565         dsec = dir->i_security;
1566         sbsec = dir->i_sb->s_security;
1567
1568         sid = tsec->sid;
1569         newsid = tsec->create_sid;
1570
1571         COMMON_AUDIT_DATA_INIT(&ad, FS);
1572         ad.u.fs.path.dentry = dentry;
1573
1574         rc = avc_has_perm(sid, dsec->sid, SECCLASS_DIR,
1575                           DIR__ADD_NAME | DIR__SEARCH,
1576                           &ad);
1577         if (rc)
1578                 return rc;
1579
1580         if (!newsid || !(sbsec->flags & SE_SBLABELSUPP)) {
1581                 rc = security_transition_sid(sid, dsec->sid, tclass, &newsid);
1582                 if (rc)
1583                         return rc;
1584         }
1585
1586         rc = avc_has_perm(sid, newsid, tclass, FILE__CREATE, &ad);
1587         if (rc)
1588                 return rc;
1589
1590         return avc_has_perm(newsid, sbsec->sid,
1591                             SECCLASS_FILESYSTEM,
1592                             FILESYSTEM__ASSOCIATE, &ad);
1593 }
1594
1595 /* Check whether a task can create a key. */
1596 static int may_create_key(u32 ksid,
1597                           struct task_struct *ctx)
1598 {
1599         u32 sid = task_sid(ctx);
1600
1601         return avc_has_perm(sid, ksid, SECCLASS_KEY, KEY__CREATE, NULL);
1602 }
1603
1604 #define MAY_LINK        0
1605 #define MAY_UNLINK      1
1606 #define MAY_RMDIR       2
1607
1608 /* Check whether a task can link, unlink, or rmdir a file/directory. */
1609 static int may_link(struct inode *dir,
1610                     struct dentry *dentry,
1611                     int kind)
1612
1613 {
1614         struct inode_security_struct *dsec, *isec;
1615         struct common_audit_data ad;
1616         u32 sid = current_sid();
1617         u32 av;
1618         int rc;
1619
1620         dsec = dir->i_security;
1621         isec = dentry->d_inode->i_security;
1622
1623         COMMON_AUDIT_DATA_INIT(&ad, FS);
1624         ad.u.fs.path.dentry = dentry;
1625
1626         av = DIR__SEARCH;
1627         av |= (kind ? DIR__REMOVE_NAME : DIR__ADD_NAME);
1628         rc = avc_has_perm(sid, dsec->sid, SECCLASS_DIR, av, &ad);
1629         if (rc)
1630                 return rc;
1631
1632         switch (kind) {
1633         case MAY_LINK:
1634                 av = FILE__LINK;
1635                 break;
1636         case MAY_UNLINK:
1637                 av = FILE__UNLINK;
1638                 break;
1639         case MAY_RMDIR:
1640                 av = DIR__RMDIR;
1641                 break;
1642         default:
1643                 printk(KERN_WARNING "SELinux: %s:  unrecognized kind %d\n",
1644                         __func__, kind);
1645                 return 0;
1646         }
1647
1648         rc = avc_has_perm(sid, isec->sid, isec->sclass, av, &ad);
1649         return rc;
1650 }
1651
1652 static inline int may_rename(struct inode *old_dir,
1653                              struct dentry *old_dentry,
1654                              struct inode *new_dir,
1655                              struct dentry *new_dentry)
1656 {
1657         struct inode_security_struct *old_dsec, *new_dsec, *old_isec, *new_isec;
1658         struct common_audit_data ad;
1659         u32 sid = current_sid();
1660         u32 av;
1661         int old_is_dir, new_is_dir;
1662         int rc;
1663
1664         old_dsec = old_dir->i_security;
1665         old_isec = old_dentry->d_inode->i_security;
1666         old_is_dir = S_ISDIR(old_dentry->d_inode->i_mode);
1667         new_dsec = new_dir->i_security;
1668
1669         COMMON_AUDIT_DATA_INIT(&ad, FS);
1670
1671         ad.u.fs.path.dentry = old_dentry;
1672         rc = avc_has_perm(sid, old_dsec->sid, SECCLASS_DIR,
1673                           DIR__REMOVE_NAME | DIR__SEARCH, &ad);
1674         if (rc)
1675                 return rc;
1676         rc = avc_has_perm(sid, old_isec->sid,
1677                           old_isec->sclass, FILE__RENAME, &ad);
1678         if (rc)
1679                 return rc;
1680         if (old_is_dir && new_dir != old_dir) {
1681                 rc = avc_has_perm(sid, old_isec->sid,
1682                                   old_isec->sclass, DIR__REPARENT, &ad);
1683                 if (rc)
1684                         return rc;
1685         }
1686
1687         ad.u.fs.path.dentry = new_dentry;
1688         av = DIR__ADD_NAME | DIR__SEARCH;
1689         if (new_dentry->d_inode)
1690                 av |= DIR__REMOVE_NAME;
1691         rc = avc_has_perm(sid, new_dsec->sid, SECCLASS_DIR, av, &ad);
1692         if (rc)
1693                 return rc;
1694         if (new_dentry->d_inode) {
1695                 new_isec = new_dentry->d_inode->i_security;
1696                 new_is_dir = S_ISDIR(new_dentry->d_inode->i_mode);
1697                 rc = avc_has_perm(sid, new_isec->sid,
1698                                   new_isec->sclass,
1699                                   (new_is_dir ? DIR__RMDIR : FILE__UNLINK), &ad);
1700                 if (rc)
1701                         return rc;
1702         }
1703
1704         return 0;
1705 }
1706
1707 /* Check whether a task can perform a filesystem operation. */
1708 static int superblock_has_perm(const struct cred *cred,
1709                                struct super_block *sb,
1710                                u32 perms,
1711                                struct common_audit_data *ad)
1712 {
1713         struct superblock_security_struct *sbsec;
1714         u32 sid = cred_sid(cred);
1715
1716         sbsec = sb->s_security;
1717         return avc_has_perm(sid, sbsec->sid, SECCLASS_FILESYSTEM, perms, ad);
1718 }
1719
1720 /* Convert a Linux mode and permission mask to an access vector. */
1721 static inline u32 file_mask_to_av(int mode, int mask)
1722 {
1723         u32 av = 0;
1724
1725         if ((mode & S_IFMT) != S_IFDIR) {
1726                 if (mask & MAY_EXEC)
1727                         av |= FILE__EXECUTE;
1728                 if (mask & MAY_READ)
1729                         av |= FILE__READ;
1730
1731                 if (mask & MAY_APPEND)
1732                         av |= FILE__APPEND;
1733                 else if (mask & MAY_WRITE)
1734                         av |= FILE__WRITE;
1735
1736         } else {
1737                 if (mask & MAY_EXEC)
1738                         av |= DIR__SEARCH;
1739                 if (mask & MAY_WRITE)
1740                         av |= DIR__WRITE;
1741                 if (mask & MAY_READ)
1742                         av |= DIR__READ;
1743         }
1744
1745         return av;
1746 }
1747
1748 /* Convert a Linux file to an access vector. */
1749 static inline u32 file_to_av(struct file *file)
1750 {
1751         u32 av = 0;
1752
1753         if (file->f_mode & FMODE_READ)
1754                 av |= FILE__READ;
1755         if (file->f_mode & FMODE_WRITE) {
1756                 if (file->f_flags & O_APPEND)
1757                         av |= FILE__APPEND;
1758                 else
1759                         av |= FILE__WRITE;
1760         }
1761         if (!av) {
1762                 /*
1763                  * Special file opened with flags 3 for ioctl-only use.
1764                  */
1765                 av = FILE__IOCTL;
1766         }
1767
1768         return av;
1769 }
1770
1771 /*
1772  * Convert a file to an access vector and include the correct open
1773  * open permission.
1774  */
1775 static inline u32 open_file_to_av(struct file *file)
1776 {
1777         u32 av = file_to_av(file);
1778
1779         if (selinux_policycap_openperm)
1780                 av |= FILE__OPEN;
1781
1782         return av;
1783 }
1784
1785 /* Hook functions begin here. */
1786
1787 static int selinux_ptrace_access_check(struct task_struct *child,
1788                                      unsigned int mode)
1789 {
1790         int rc;
1791
1792         rc = cap_ptrace_access_check(child, mode);
1793         if (rc)
1794                 return rc;
1795
1796         if (mode == PTRACE_MODE_READ) {
1797                 u32 sid = current_sid();
1798                 u32 csid = task_sid(child);
1799                 return avc_has_perm(sid, csid, SECCLASS_FILE, FILE__READ, NULL);
1800         }
1801
1802         return current_has_perm(child, PROCESS__PTRACE);
1803 }
1804
1805 static int selinux_ptrace_traceme(struct task_struct *parent)
1806 {
1807         int rc;
1808
1809         rc = cap_ptrace_traceme(parent);
1810         if (rc)
1811                 return rc;
1812
1813         return task_has_perm(parent, current, PROCESS__PTRACE);
1814 }
1815
1816 static int selinux_capget(struct task_struct *target, kernel_cap_t *effective,
1817                           kernel_cap_t *inheritable, kernel_cap_t *permitted)
1818 {
1819         int error;
1820
1821         error = current_has_perm(target, PROCESS__GETCAP);
1822         if (error)
1823                 return error;
1824
1825         return cap_capget(target, effective, inheritable, permitted);
1826 }
1827
1828 static int selinux_capset(struct cred *new, const struct cred *old,
1829                           const kernel_cap_t *effective,
1830                           const kernel_cap_t *inheritable,
1831                           const kernel_cap_t *permitted)
1832 {
1833         int error;
1834
1835         error = cap_capset(new, old,
1836                                       effective, inheritable, permitted);
1837         if (error)
1838                 return error;
1839
1840         return cred_has_perm(old, new, PROCESS__SETCAP);
1841 }
1842
1843 /*
1844  * (This comment used to live with the selinux_task_setuid hook,
1845  * which was removed).
1846  *
1847  * Since setuid only affects the current process, and since the SELinux
1848  * controls are not based on the Linux identity attributes, SELinux does not
1849  * need to control this operation.  However, SELinux does control the use of
1850  * the CAP_SETUID and CAP_SETGID capabilities using the capable hook.
1851  */
1852
1853 static int selinux_capable(struct task_struct *tsk, const struct cred *cred,
1854                            int cap, int audit)
1855 {
1856         int rc;
1857
1858         rc = cap_capable(tsk, cred, cap, audit);
1859         if (rc)
1860                 return rc;
1861
1862         return task_has_capability(tsk, cred, cap, audit);
1863 }
1864
1865 static int selinux_sysctl_get_sid(ctl_table *table, u16 tclass, u32 *sid)
1866 {
1867         int buflen, rc;
1868         char *buffer, *path, *end;
1869
1870         rc = -ENOMEM;
1871         buffer = (char *)__get_free_page(GFP_KERNEL);
1872         if (!buffer)
1873                 goto out;
1874
1875         buflen = PAGE_SIZE;
1876         end = buffer+buflen;
1877         *--end = '\0';
1878         buflen--;
1879         path = end-1;
1880         *path = '/';
1881         while (table) {
1882                 const char *name = table->procname;
1883                 size_t namelen = strlen(name);
1884                 buflen -= namelen + 1;
1885                 if (buflen < 0)
1886                         goto out_free;
1887                 end -= namelen;
1888                 memcpy(end, name, namelen);
1889                 *--end = '/';
1890                 path = end;
1891                 table = table->parent;
1892         }
1893         buflen -= 4;
1894         if (buflen < 0)
1895                 goto out_free;
1896         end -= 4;
1897         memcpy(end, "/sys", 4);
1898         path = end;
1899         rc = security_genfs_sid("proc", path, tclass, sid);
1900 out_free:
1901         free_page((unsigned long)buffer);
1902 out:
1903         return rc;
1904 }
1905
1906 static int selinux_sysctl(ctl_table *table, int op)
1907 {
1908         int error = 0;
1909         u32 av;
1910         u32 tsid, sid;
1911         int rc;
1912
1913         sid = current_sid();
1914
1915         rc = selinux_sysctl_get_sid(table, (op == 0001) ?
1916                                     SECCLASS_DIR : SECCLASS_FILE, &tsid);
1917         if (rc) {
1918                 /* Default to the well-defined sysctl SID. */
1919                 tsid = SECINITSID_SYSCTL;
1920         }
1921
1922         /* The op values are "defined" in sysctl.c, thereby creating
1923          * a bad coupling between this module and sysctl.c */
1924         if (op == 001) {
1925                 error = avc_has_perm(sid, tsid,
1926                                      SECCLASS_DIR, DIR__SEARCH, NULL);
1927         } else {
1928                 av = 0;
1929                 if (op & 004)
1930                         av |= FILE__READ;
1931                 if (op & 002)
1932                         av |= FILE__WRITE;
1933                 if (av)
1934                         error = avc_has_perm(sid, tsid,
1935                                              SECCLASS_FILE, av, NULL);
1936         }
1937
1938         return error;
1939 }
1940
1941 static int selinux_quotactl(int cmds, int type, int id, struct super_block *sb)
1942 {
1943         const struct cred *cred = current_cred();
1944         int rc = 0;
1945
1946         if (!sb)
1947                 return 0;
1948
1949         switch (cmds) {
1950         case Q_SYNC:
1951         case Q_QUOTAON:
1952         case Q_QUOTAOFF:
1953         case Q_SETINFO:
1954         case Q_SETQUOTA:
1955                 rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAMOD, NULL);
1956                 break;
1957         case Q_GETFMT:
1958         case Q_GETINFO:
1959         case Q_GETQUOTA:
1960                 rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAGET, NULL);
1961                 break;
1962         default:
1963                 rc = 0;  /* let the kernel handle invalid cmds */
1964                 break;
1965         }
1966         return rc;
1967 }
1968
1969 static int selinux_quota_on(struct dentry *dentry)
1970 {
1971         const struct cred *cred = current_cred();
1972
1973         return dentry_has_perm(cred, NULL, dentry, FILE__QUOTAON);
1974 }
1975
1976 static int selinux_syslog(int type)
1977 {
1978         int rc;
1979
1980         switch (type) {
1981         case SYSLOG_ACTION_READ_ALL:    /* Read last kernel messages */
1982         case SYSLOG_ACTION_SIZE_BUFFER: /* Return size of the log buffer */
1983                 rc = task_has_system(current, SYSTEM__SYSLOG_READ);
1984                 break;
1985         case SYSLOG_ACTION_CONSOLE_OFF: /* Disable logging to console */
1986         case SYSLOG_ACTION_CONSOLE_ON:  /* Enable logging to console */
1987         /* Set level of messages printed to console */
1988         case SYSLOG_ACTION_CONSOLE_LEVEL:
1989                 rc = task_has_system(current, SYSTEM__SYSLOG_CONSOLE);
1990                 break;
1991         case SYSLOG_ACTION_CLOSE:       /* Close log */
1992         case SYSLOG_ACTION_OPEN:        /* Open log */
1993         case SYSLOG_ACTION_READ:        /* Read from log */
1994         case SYSLOG_ACTION_READ_CLEAR:  /* Read/clear last kernel messages */
1995         case SYSLOG_ACTION_CLEAR:       /* Clear ring buffer */
1996         default:
1997                 rc = task_has_system(current, SYSTEM__SYSLOG_MOD);
1998                 break;
1999         }
2000         return rc;
2001 }
2002
2003 /*
2004  * Check that a process has enough memory to allocate a new virtual
2005  * mapping. 0 means there is enough memory for the allocation to
2006  * succeed and -ENOMEM implies there is not.
2007  *
2008  * Do not audit the selinux permission check, as this is applied to all
2009  * processes that allocate mappings.
2010  */
2011 static int selinux_vm_enough_memory(struct mm_struct *mm, long pages)
2012 {
2013         int rc, cap_sys_admin = 0;
2014
2015         rc = selinux_capable(current, current_cred(), CAP_SYS_ADMIN,
2016                              SECURITY_CAP_NOAUDIT);
2017         if (rc == 0)
2018                 cap_sys_admin = 1;
2019
2020         return __vm_enough_memory(mm, pages, cap_sys_admin);
2021 }
2022
2023 /* binprm security operations */
2024
2025 static int selinux_bprm_set_creds(struct linux_binprm *bprm)
2026 {
2027         const struct task_security_struct *old_tsec;
2028         struct task_security_struct *new_tsec;
2029         struct inode_security_struct *isec;
2030         struct common_audit_data ad;
2031         struct inode *inode = bprm->file->f_path.dentry->d_inode;
2032         int rc;
2033
2034         rc = cap_bprm_set_creds(bprm);
2035         if (rc)
2036                 return rc;
2037
2038         /* SELinux context only depends on initial program or script and not
2039          * the script interpreter */
2040         if (bprm->cred_prepared)
2041                 return 0;
2042
2043         old_tsec = current_security();
2044         new_tsec = bprm->cred->security;
2045         isec = inode->i_security;
2046
2047         /* Default to the current task SID. */
2048         new_tsec->sid = old_tsec->sid;
2049         new_tsec->osid = old_tsec->sid;
2050
2051         /* Reset fs, key, and sock SIDs on execve. */
2052         new_tsec->create_sid = 0;
2053         new_tsec->keycreate_sid = 0;
2054         new_tsec->sockcreate_sid = 0;
2055
2056         if (old_tsec->exec_sid) {
2057                 new_tsec->sid = old_tsec->exec_sid;
2058                 /* Reset exec SID on execve. */
2059                 new_tsec->exec_sid = 0;
2060         } else {
2061                 /* Check for a default transition on this program. */
2062                 rc = security_transition_sid(old_tsec->sid, isec->sid,
2063                                              SECCLASS_PROCESS, &new_tsec->sid);
2064                 if (rc)
2065                         return rc;
2066         }
2067
2068         COMMON_AUDIT_DATA_INIT(&ad, FS);
2069         ad.u.fs.path = bprm->file->f_path;
2070
2071         if (bprm->file->f_path.mnt->mnt_flags & MNT_NOSUID)
2072                 new_tsec->sid = old_tsec->sid;
2073
2074         if (new_tsec->sid == old_tsec->sid) {
2075                 rc = avc_has_perm(old_tsec->sid, isec->sid,
2076                                   SECCLASS_FILE, FILE__EXECUTE_NO_TRANS, &ad);
2077                 if (rc)
2078                         return rc;
2079         } else {
2080                 /* Check permissions for the transition. */
2081                 rc = avc_has_perm(old_tsec->sid, new_tsec->sid,
2082                                   SECCLASS_PROCESS, PROCESS__TRANSITION, &ad);
2083                 if (rc)
2084                         return rc;
2085
2086                 rc = avc_has_perm(new_tsec->sid, isec->sid,
2087                                   SECCLASS_FILE, FILE__ENTRYPOINT, &ad);
2088                 if (rc)
2089                         return rc;
2090
2091                 /* Check for shared state */
2092                 if (bprm->unsafe & LSM_UNSAFE_SHARE) {
2093                         rc = avc_has_perm(old_tsec->sid, new_tsec->sid,
2094                                           SECCLASS_PROCESS, PROCESS__SHARE,
2095                                           NULL);
2096                         if (rc)
2097                                 return -EPERM;
2098                 }
2099
2100                 /* Make sure that anyone attempting to ptrace over a task that
2101                  * changes its SID has the appropriate permit */
2102                 if (bprm->unsafe &
2103                     (LSM_UNSAFE_PTRACE | LSM_UNSAFE_PTRACE_CAP)) {
2104                         struct task_struct *tracer;
2105                         struct task_security_struct *sec;
2106                         u32 ptsid = 0;
2107
2108                         rcu_read_lock();
2109                         tracer = tracehook_tracer_task(current);
2110                         if (likely(tracer != NULL)) {
2111                                 sec = __task_cred(tracer)->security;
2112                                 ptsid = sec->sid;
2113                         }
2114                         rcu_read_unlock();
2115
2116                         if (ptsid != 0) {
2117                                 rc = avc_has_perm(ptsid, new_tsec->sid,
2118                                                   SECCLASS_PROCESS,
2119                                                   PROCESS__PTRACE, NULL);
2120                                 if (rc)
2121                                         return -EPERM;
2122                         }
2123                 }
2124
2125                 /* Clear any possibly unsafe personality bits on exec: */
2126                 bprm->per_clear |= PER_CLEAR_ON_SETID;
2127         }
2128
2129         return 0;
2130 }
2131
2132 static int selinux_bprm_secureexec(struct linux_binprm *bprm)
2133 {
2134         const struct task_security_struct *tsec = current_security();
2135         u32 sid, osid;
2136         int atsecure = 0;
2137
2138         sid = tsec->sid;
2139         osid = tsec->osid;
2140
2141         if (osid != sid) {
2142                 /* Enable secure mode for SIDs transitions unless
2143                    the noatsecure permission is granted between
2144                    the two SIDs, i.e. ahp returns 0. */
2145                 atsecure = avc_has_perm(osid, sid,
2146                                         SECCLASS_PROCESS,
2147                                         PROCESS__NOATSECURE, NULL);
2148         }
2149
2150         return (atsecure || cap_bprm_secureexec(bprm));
2151 }
2152
2153 extern struct vfsmount *selinuxfs_mount;
2154 extern struct dentry *selinux_null;
2155
2156 /* Derived from fs/exec.c:flush_old_files. */
2157 static inline void flush_unauthorized_files(const struct cred *cred,
2158                                             struct files_struct *files)
2159 {
2160         struct common_audit_data ad;
2161         struct file *file, *devnull = NULL;
2162         struct tty_struct *tty;
2163         struct fdtable *fdt;
2164         long j = -1;
2165         int drop_tty = 0;
2166
2167         tty = get_current_tty();
2168         if (tty) {
2169                 spin_lock(&tty_files_lock);
2170                 if (!list_empty(&tty->tty_files)) {
2171                         struct tty_file_private *file_priv;
2172                         struct inode *inode;
2173
2174                         /* Revalidate access to controlling tty.
2175                            Use inode_has_perm on the tty inode directly rather
2176                            than using file_has_perm, as this particular open
2177                            file may belong to another process and we are only
2178                            interested in the inode-based check here. */
2179                         file_priv = list_first_entry(&tty->tty_files,
2180                                                 struct tty_file_private, list);
2181                         file = file_priv->file;
2182                         inode = file->f_path.dentry->d_inode;
2183                         if (inode_has_perm(cred, inode,
2184                                            FILE__READ | FILE__WRITE, NULL)) {
2185                                 drop_tty = 1;
2186                         }
2187                 }
2188                 spin_unlock(&tty_files_lock);
2189                 tty_kref_put(tty);
2190         }
2191         /* Reset controlling tty. */
2192         if (drop_tty)
2193                 no_tty();
2194
2195         /* Revalidate access to inherited open files. */
2196
2197         COMMON_AUDIT_DATA_INIT(&ad, FS);
2198
2199         spin_lock(&files->file_lock);
2200         for (;;) {
2201                 unsigned long set, i;
2202                 int fd;
2203
2204                 j++;
2205                 i = j * __NFDBITS;
2206                 fdt = files_fdtable(files);
2207                 if (i >= fdt->max_fds)
2208                         break;
2209                 set = fdt->open_fds->fds_bits[j];
2210                 if (!set)
2211                         continue;
2212                 spin_unlock(&files->file_lock);
2213                 for ( ; set ; i++, set >>= 1) {
2214                         if (set & 1) {
2215                                 file = fget(i);
2216                                 if (!file)
2217                                         continue;
2218                                 if (file_has_perm(cred,
2219                                                   file,
2220                                                   file_to_av(file))) {
2221                                         sys_close(i);
2222                                         fd = get_unused_fd();
2223                                         if (fd != i) {
2224                                                 if (fd >= 0)
2225                                                         put_unused_fd(fd);
2226                                                 fput(file);
2227                                                 continue;
2228                                         }
2229                                         if (devnull) {
2230                                                 get_file(devnull);
2231                                         } else {
2232                                                 devnull = dentry_open(
2233                                                         dget(selinux_null),
2234                                                         mntget(selinuxfs_mount),
2235                                                         O_RDWR, cred);
2236                                                 if (IS_ERR(devnull)) {
2237                                                         devnull = NULL;
2238                                                         put_unused_fd(fd);
2239                                                         fput(file);
2240                                                         continue;
2241                                                 }
2242                                         }
2243                                         fd_install(fd, devnull);
2244                                 }
2245                                 fput(file);
2246                         }
2247                 }
2248                 spin_lock(&files->file_lock);
2249
2250         }
2251         spin_unlock(&files->file_lock);
2252 }
2253
2254 /*
2255  * Prepare a process for imminent new credential changes due to exec
2256  */
2257 static void selinux_bprm_committing_creds(struct linux_binprm *bprm)
2258 {
2259         struct task_security_struct *new_tsec;
2260         struct rlimit *rlim, *initrlim;
2261         int rc, i;
2262
2263         new_tsec = bprm->cred->security;
2264         if (new_tsec->sid == new_tsec->osid)
2265                 return;
2266
2267         /* Close files for which the new task SID is not authorized. */
2268         flush_unauthorized_files(bprm->cred, current->files);
2269
2270         /* Always clear parent death signal on SID transitions. */
2271         current->pdeath_signal = 0;
2272
2273         /* Check whether the new SID can inherit resource limits from the old
2274          * SID.  If not, reset all soft limits to the lower of the current
2275          * task's hard limit and the init task's soft limit.
2276          *
2277          * Note that the setting of hard limits (even to lower them) can be
2278          * controlled by the setrlimit check.  The inclusion of the init task's
2279          * soft limit into the computation is to avoid resetting soft limits
2280          * higher than the default soft limit for cases where the default is
2281          * lower than the hard limit, e.g. RLIMIT_CORE or RLIMIT_STACK.
2282          */
2283         rc = avc_has_perm(new_tsec->osid, new_tsec->sid, SECCLASS_PROCESS,
2284                           PROCESS__RLIMITINH, NULL);
2285         if (rc) {
2286                 /* protect against do_prlimit() */
2287                 task_lock(current);
2288                 for (i = 0; i < RLIM_NLIMITS; i++) {
2289                         rlim = current->signal->rlim + i;
2290                         initrlim = init_task.signal->rlim + i;
2291                         rlim->rlim_cur = min(rlim->rlim_max, initrlim->rlim_cur);
2292                 }
2293                 task_unlock(current);
2294                 update_rlimit_cpu(current, rlimit(RLIMIT_CPU));
2295         }
2296 }
2297
2298 /*
2299  * Clean up the process immediately after the installation of new credentials
2300  * due to exec
2301  */
2302 static void selinux_bprm_committed_creds(struct linux_binprm *bprm)
2303 {
2304         const struct task_security_struct *tsec = current_security();
2305         struct itimerval itimer;
2306         u32 osid, sid;
2307         int rc, i;
2308
2309         osid = tsec->osid;
2310         sid = tsec->sid;
2311
2312         if (sid == osid)
2313                 return;
2314
2315         /* Check whether the new SID can inherit signal state from the old SID.
2316          * If not, clear itimers to avoid subsequent signal generation and
2317          * flush and unblock signals.
2318          *
2319          * This must occur _after_ the task SID has been updated so that any
2320          * kill done after the flush will be checked against the new SID.
2321          */
2322         rc = avc_has_perm(osid, sid, SECCLASS_PROCESS, PROCESS__SIGINH, NULL);
2323         if (rc) {
2324                 memset(&itimer, 0, sizeof itimer);
2325                 for (i = 0; i < 3; i++)
2326                         do_setitimer(i, &itimer, NULL);
2327                 spin_lock_irq(&current->sighand->siglock);
2328                 if (!(current->signal->flags & SIGNAL_GROUP_EXIT)) {
2329                         __flush_signals(current);
2330                         flush_signal_handlers(current, 1);
2331                         sigemptyset(&current->blocked);
2332                 }
2333                 spin_unlock_irq(&current->sighand->siglock);
2334         }
2335
2336         /* Wake up the parent if it is waiting so that it can recheck
2337          * wait permission to the new task SID. */
2338         read_lock(&tasklist_lock);
2339         __wake_up_parent(current, current->real_parent);
2340         read_unlock(&tasklist_lock);
2341 }
2342
2343 /* superblock security operations */
2344
2345 static int selinux_sb_alloc_security(struct super_block *sb)
2346 {
2347         return superblock_alloc_security(sb);
2348 }
2349
2350 static void selinux_sb_free_security(struct super_block *sb)
2351 {
2352         superblock_free_security(sb);
2353 }
2354
2355 static inline int match_prefix(char *prefix, int plen, char *option, int olen)
2356 {
2357         if (plen > olen)
2358                 return 0;
2359
2360         return !memcmp(prefix, option, plen);
2361 }
2362
2363 static inline int selinux_option(char *option, int len)
2364 {
2365         return (match_prefix(CONTEXT_STR, sizeof(CONTEXT_STR)-1, option, len) ||
2366                 match_prefix(FSCONTEXT_STR, sizeof(FSCONTEXT_STR)-1, option, len) ||
2367                 match_prefix(DEFCONTEXT_STR, sizeof(DEFCONTEXT_STR)-1, option, len) ||
2368                 match_prefix(ROOTCONTEXT_STR, sizeof(ROOTCONTEXT_STR)-1, option, len) ||
2369                 match_prefix(LABELSUPP_STR, sizeof(LABELSUPP_STR)-1, option, len));
2370 }
2371
2372 static inline void take_option(char **to, char *from, int *first, int len)
2373 {
2374         if (!*first) {
2375                 **to = ',';
2376                 *to += 1;
2377         } else
2378                 *first = 0;
2379         memcpy(*to, from, len);
2380         *to += len;
2381 }
2382
2383 static inline void take_selinux_option(char **to, char *from, int *first,
2384                                        int len)
2385 {
2386         int current_size = 0;
2387
2388         if (!*first) {
2389                 **to = '|';
2390                 *to += 1;
2391         } else
2392                 *first = 0;
2393
2394         while (current_size < len) {
2395                 if (*from != '"') {
2396                         **to = *from;
2397                         *to += 1;
2398                 }
2399                 from += 1;
2400                 current_size += 1;
2401         }
2402 }
2403
2404 static int selinux_sb_copy_data(char *orig, char *copy)
2405 {
2406         int fnosec, fsec, rc = 0;
2407         char *in_save, *in_curr, *in_end;
2408         char *sec_curr, *nosec_save, *nosec;
2409         int open_quote = 0;
2410
2411         in_curr = orig;
2412         sec_curr = copy;
2413
2414         nosec = (char *)get_zeroed_page(GFP_KERNEL);
2415         if (!nosec) {
2416                 rc = -ENOMEM;
2417                 goto out;
2418         }
2419
2420         nosec_save = nosec;
2421         fnosec = fsec = 1;
2422         in_save = in_end = orig;
2423
2424         do {
2425                 if (*in_end == '"')
2426                         open_quote = !open_quote;
2427                 if ((*in_end == ',' && open_quote == 0) ||
2428                                 *in_end == '\0') {
2429                         int len = in_end - in_curr;
2430
2431                         if (selinux_option(in_curr, len))
2432                                 take_selinux_option(&sec_curr, in_curr, &fsec, len);
2433                         else
2434                                 take_option(&nosec, in_curr, &fnosec, len);
2435
2436                         in_curr = in_end + 1;
2437                 }
2438         } while (*in_end++);
2439
2440         strcpy(in_save, nosec_save);
2441         free_page((unsigned long)nosec_save);
2442 out:
2443         return rc;
2444 }
2445
2446 static int selinux_sb_kern_mount(struct super_block *sb, int flags, void *data)
2447 {
2448         const struct cred *cred = current_cred();
2449         struct common_audit_data ad;
2450         int rc;
2451
2452         rc = superblock_doinit(sb, data);
2453         if (rc)
2454                 return rc;
2455
2456         /* Allow all mounts performed by the kernel */
2457         if (flags & MS_KERNMOUNT)
2458                 return 0;
2459
2460         COMMON_AUDIT_DATA_INIT(&ad, FS);
2461         ad.u.fs.path.dentry = sb->s_root;
2462         return superblock_has_perm(cred, sb, FILESYSTEM__MOUNT, &ad);
2463 }
2464
2465 static int selinux_sb_statfs(struct dentry *dentry)
2466 {
2467         const struct cred *cred = current_cred();
2468         struct common_audit_data ad;
2469
2470         COMMON_AUDIT_DATA_INIT(&ad, FS);
2471         ad.u.fs.path.dentry = dentry->d_sb->s_root;
2472         return superblock_has_perm(cred, dentry->d_sb, FILESYSTEM__GETATTR, &ad);
2473 }
2474
2475 static int selinux_mount(char *dev_name,
2476                          struct path *path,
2477                          char *type,
2478                          unsigned long flags,
2479                          void *data)
2480 {
2481         const struct cred *cred = current_cred();
2482
2483         if (flags & MS_REMOUNT)
2484                 return superblock_has_perm(cred, path->mnt->mnt_sb,
2485                                            FILESYSTEM__REMOUNT, NULL);
2486         else
2487                 return dentry_has_perm(cred, path->mnt, path->dentry,
2488                                        FILE__MOUNTON);
2489 }
2490
2491 static int selinux_umount(struct vfsmount *mnt, int flags)
2492 {
2493         const struct cred *cred = current_cred();
2494
2495         return superblock_has_perm(cred, mnt->mnt_sb,
2496                                    FILESYSTEM__UNMOUNT, NULL);
2497 }
2498
2499 /* inode security operations */
2500
2501 static int selinux_inode_alloc_security(struct inode *inode)
2502 {
2503         return inode_alloc_security(inode);
2504 }
2505
2506 static void selinux_inode_free_security(struct inode *inode)
2507 {
2508         inode_free_security(inode);
2509 }
2510
2511 static int selinux_inode_init_security(struct inode *inode, struct inode *dir,
2512                                        char **name, void **value,
2513                                        size_t *len)
2514 {
2515         const struct task_security_struct *tsec = current_security();
2516         struct inode_security_struct *dsec;
2517         struct superblock_security_struct *sbsec;
2518         u32 sid, newsid, clen;
2519         int rc;
2520         char *namep = NULL, *context;
2521
2522         dsec = dir->i_security;
2523         sbsec = dir->i_sb->s_security;
2524
2525         sid = tsec->sid;
2526         newsid = tsec->create_sid;
2527
2528         if ((sbsec->flags & SE_SBINITIALIZED) &&
2529             (sbsec->behavior == SECURITY_FS_USE_MNTPOINT))
2530                 newsid = sbsec->mntpoint_sid;
2531         else if (!newsid || !(sbsec->flags & SE_SBLABELSUPP)) {
2532                 rc = security_transition_sid(sid, dsec->sid,
2533                                              inode_mode_to_security_class(inode->i_mode),
2534                                              &newsid);
2535                 if (rc) {
2536                         printk(KERN_WARNING "%s:  "
2537                                "security_transition_sid failed, rc=%d (dev=%s "
2538                                "ino=%ld)\n",
2539                                __func__,
2540                                -rc, inode->i_sb->s_id, inode->i_ino);
2541                         return rc;
2542                 }
2543         }
2544
2545         /* Possibly defer initialization to selinux_complete_init. */
2546         if (sbsec->flags & SE_SBINITIALIZED) {
2547                 struct inode_security_struct *isec = inode->i_security;
2548                 isec->sclass = inode_mode_to_security_class(inode->i_mode);
2549                 isec->sid = newsid;
2550                 isec->initialized = 1;
2551         }
2552
2553         if (!ss_initialized || !(sbsec->flags & SE_SBLABELSUPP))
2554                 return -EOPNOTSUPP;
2555
2556         if (name) {
2557                 namep = kstrdup(XATTR_SELINUX_SUFFIX, GFP_NOFS);
2558                 if (!namep)
2559                         return -ENOMEM;
2560                 *name = namep;
2561         }
2562
2563         if (value && len) {
2564                 rc = security_sid_to_context_force(newsid, &context, &clen);
2565                 if (rc) {
2566                         kfree(namep);
2567                         return rc;
2568                 }
2569                 *value = context;
2570                 *len = clen;
2571         }
2572
2573         return 0;
2574 }
2575
2576 static int selinux_inode_create(struct inode *dir, struct dentry *dentry, int mask)
2577 {
2578         return may_create(dir, dentry, SECCLASS_FILE);
2579 }
2580
2581 static int selinux_inode_link(struct dentry *old_dentry, struct inode *dir, struct dentry *new_dentry)
2582 {
2583         return may_link(dir, old_dentry, MAY_LINK);
2584 }
2585
2586 static int selinux_inode_unlink(struct inode *dir, struct dentry *dentry)
2587 {
2588         return may_link(dir, dentry, MAY_UNLINK);
2589 }
2590
2591 static int selinux_inode_symlink(struct inode *dir, struct dentry *dentry, const char *name)
2592 {
2593         return may_create(dir, dentry, SECCLASS_LNK_FILE);
2594 }
2595
2596 static int selinux_inode_mkdir(struct inode *dir, struct dentry *dentry, int mask)
2597 {
2598         return may_create(dir, dentry, SECCLASS_DIR);
2599 }
2600
2601 static int selinux_inode_rmdir(struct inode *dir, struct dentry *dentry)
2602 {
2603         return may_link(dir, dentry, MAY_RMDIR);
2604 }
2605
2606 static int selinux_inode_mknod(struct inode *dir, struct dentry *dentry, int mode, dev_t dev)
2607 {
2608         return may_create(dir, dentry, inode_mode_to_security_class(mode));
2609 }
2610
2611 static int selinux_inode_rename(struct inode *old_inode, struct dentry *old_dentry,
2612                                 struct inode *new_inode, struct dentry *new_dentry)
2613 {
2614         return may_rename(old_inode, old_dentry, new_inode, new_dentry);
2615 }
2616
2617 static int selinux_inode_readlink(struct dentry *dentry)
2618 {
2619         const struct cred *cred = current_cred();
2620
2621         return dentry_has_perm(cred, NULL, dentry, FILE__READ);
2622 }
2623
2624 static int selinux_inode_follow_link(struct dentry *dentry, struct nameidata *nameidata)
2625 {
2626         const struct cred *cred = current_cred();
2627
2628         return dentry_has_perm(cred, NULL, dentry, FILE__READ);
2629 }
2630
2631 static int selinux_inode_permission(struct inode *inode, int mask)
2632 {
2633         const struct cred *cred = current_cred();
2634         struct common_audit_data ad;
2635         u32 perms;
2636         bool from_access;
2637
2638         from_access = mask & MAY_ACCESS;
2639         mask &= (MAY_READ|MAY_WRITE|MAY_EXEC|MAY_APPEND);
2640
2641         /* No permission to check.  Existence test. */
2642         if (!mask)
2643                 return 0;
2644
2645         COMMON_AUDIT_DATA_INIT(&ad, FS);
2646         ad.u.fs.inode = inode;
2647
2648         if (from_access)
2649                 ad.selinux_audit_data.auditdeny |= FILE__AUDIT_ACCESS;
2650
2651         perms = file_mask_to_av(inode->i_mode, mask);
2652
2653         return inode_has_perm(cred, inode, perms, &ad);
2654 }
2655
2656 static int selinux_inode_setattr(struct dentry *dentry, struct iattr *iattr)
2657 {
2658         const struct cred *cred = current_cred();
2659         unsigned int ia_valid = iattr->ia_valid;
2660
2661         /* ATTR_FORCE is just used for ATTR_KILL_S[UG]ID. */
2662         if (ia_valid & ATTR_FORCE) {
2663                 ia_valid &= ~(ATTR_KILL_SUID | ATTR_KILL_SGID | ATTR_MODE |
2664                               ATTR_FORCE);
2665                 if (!ia_valid)
2666                         return 0;
2667         }
2668
2669         if (ia_valid & (ATTR_MODE | ATTR_UID | ATTR_GID |
2670                         ATTR_ATIME_SET | ATTR_MTIME_SET | ATTR_TIMES_SET))
2671                 return dentry_has_perm(cred, NULL, dentry, FILE__SETATTR);
2672
2673         return dentry_has_perm(cred, NULL, dentry, FILE__WRITE);
2674 }
2675
2676 static int selinux_inode_getattr(struct vfsmount *mnt, struct dentry *dentry)
2677 {
2678         const struct cred *cred = current_cred();
2679
2680         return dentry_has_perm(cred, mnt, dentry, FILE__GETATTR);
2681 }
2682
2683 static int selinux_inode_setotherxattr(struct dentry *dentry, const char *name)
2684 {
2685         const struct cred *cred = current_cred();
2686
2687         if (!strncmp(name, XATTR_SECURITY_PREFIX,
2688                      sizeof XATTR_SECURITY_PREFIX - 1)) {
2689                 if (!strcmp(name, XATTR_NAME_CAPS)) {
2690                         if (!capable(CAP_SETFCAP))
2691                                 return -EPERM;
2692                 } else if (!capable(CAP_SYS_ADMIN)) {
2693                         /* A different attribute in the security namespace.
2694                            Restrict to administrator. */
2695                         return -EPERM;
2696                 }
2697         }
2698
2699         /* Not an attribute we recognize, so just check the
2700            ordinary setattr permission. */
2701         return dentry_has_perm(cred, NULL, dentry, FILE__SETATTR);
2702 }
2703
2704 static int selinux_inode_setxattr(struct dentry *dentry, const char *name,
2705                                   const void *value, size_t size, int flags)
2706 {
2707         struct inode *inode = dentry->d_inode;
2708         struct inode_security_struct *isec = inode->i_security;
2709         struct superblock_security_struct *sbsec;
2710         struct common_audit_data ad;
2711         u32 newsid, sid = current_sid();
2712         int rc = 0;
2713
2714         if (strcmp(name, XATTR_NAME_SELINUX))
2715                 return selinux_inode_setotherxattr(dentry, name);
2716
2717         sbsec = inode->i_sb->s_security;
2718         if (!(sbsec->flags & SE_SBLABELSUPP))
2719                 return -EOPNOTSUPP;
2720
2721         if (!is_owner_or_cap(inode))
2722                 return -EPERM;
2723
2724         COMMON_AUDIT_DATA_INIT(&ad, FS);
2725         ad.u.fs.path.dentry = dentry;
2726
2727         rc = avc_has_perm(sid, isec->sid, isec->sclass,
2728                           FILE__RELABELFROM, &ad);
2729         if (rc)
2730                 return rc;
2731
2732         rc = security_context_to_sid(value, size, &newsid);
2733         if (rc == -EINVAL) {
2734                 if (!capable(CAP_MAC_ADMIN))
2735                         return rc;
2736                 rc = security_context_to_sid_force(value, size, &newsid);
2737         }
2738         if (rc)
2739                 return rc;
2740
2741         rc = avc_has_perm(sid, newsid, isec->sclass,
2742                           FILE__RELABELTO, &ad);
2743         if (rc)
2744                 return rc;
2745
2746         rc = security_validate_transition(isec->sid, newsid, sid,
2747                                           isec->sclass);
2748         if (rc)
2749                 return rc;
2750
2751         return avc_has_perm(newsid,
2752                             sbsec->sid,
2753                             SECCLASS_FILESYSTEM,
2754                             FILESYSTEM__ASSOCIATE,
2755                             &ad);
2756 }
2757
2758 static void selinux_inode_post_setxattr(struct dentry *dentry, const char *name,
2759                                         const void *value, size_t size,
2760                                         int flags)
2761 {
2762         struct inode *inode = dentry->d_inode;
2763         struct inode_security_struct *isec = inode->i_security;
2764         u32 newsid;
2765         int rc;
2766
2767         if (strcmp(name, XATTR_NAME_SELINUX)) {
2768                 /* Not an attribute we recognize, so nothing to do. */
2769                 return;
2770         }
2771
2772         rc = security_context_to_sid_force(value, size, &newsid);
2773         if (rc) {
2774                 printk(KERN_ERR "SELinux:  unable to map context to SID"
2775                        "for (%s, %lu), rc=%d\n",
2776                        inode->i_sb->s_id, inode->i_ino, -rc);
2777                 return;
2778         }
2779
2780         isec->sid = newsid;
2781         return;
2782 }
2783
2784 static int selinux_inode_getxattr(struct dentry *dentry, const char *name)
2785 {
2786         const struct cred *cred = current_cred();
2787
2788         return dentry_has_perm(cred, NULL, dentry, FILE__GETATTR);
2789 }
2790
2791 static int selinux_inode_listxattr(struct dentry *dentry)
2792 {
2793         const struct cred *cred = current_cred();
2794
2795         return dentry_has_perm(cred, NULL, dentry, FILE__GETATTR);
2796 }
2797
2798 static int selinux_inode_removexattr(struct dentry *dentry, const char *name)
2799 {
2800         if (strcmp(name, XATTR_NAME_SELINUX))
2801                 return selinux_inode_setotherxattr(dentry, name);
2802
2803         /* No one is allowed to remove a SELinux security label.
2804            You can change the label, but all data must be labeled. */
2805         return -EACCES;
2806 }
2807
2808 /*
2809  * Copy the inode security context value to the user.
2810  *
2811  * Permission check is handled by selinux_inode_getxattr hook.
2812  */
2813 static int selinux_inode_getsecurity(const struct inode *inode, const char *name, void **buffer, bool alloc)
2814 {
2815         u32 size;
2816         int error;
2817         char *context = NULL;
2818         struct inode_security_struct *isec = inode->i_security;
2819
2820         if (strcmp(name, XATTR_SELINUX_SUFFIX))
2821                 return -EOPNOTSUPP;
2822
2823         /*
2824          * If the caller has CAP_MAC_ADMIN, then get the raw context
2825          * value even if it is not defined by current policy; otherwise,
2826          * use the in-core value under current policy.
2827          * Use the non-auditing forms of the permission checks since
2828          * getxattr may be called by unprivileged processes commonly
2829          * and lack of permission just means that we fall back to the
2830          * in-core context value, not a denial.
2831          */
2832         error = selinux_capable(current, current_cred(), CAP_MAC_ADMIN,
2833                                 SECURITY_CAP_NOAUDIT);
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         isec->initialized = 1;
2870         return 0;
2871 }
2872
2873 static int selinux_inode_listsecurity(struct inode *inode, char *buffer, size_t buffer_size)
2874 {
2875         const int len = sizeof(XATTR_NAME_SELINUX);
2876         if (buffer && len <= buffer_size)
2877                 memcpy(buffer, XATTR_NAME_SELINUX, len);
2878         return len;
2879 }
2880
2881 static void selinux_inode_getsecid(const struct inode *inode, u32 *secid)
2882 {
2883         struct inode_security_struct *isec = inode->i_security;
2884         *secid = isec->sid;
2885 }
2886
2887 /* file security operations */
2888
2889 static int selinux_revalidate_file_permission(struct file *file, int mask)
2890 {
2891         const struct cred *cred = current_cred();
2892         struct inode *inode = file->f_path.dentry->d_inode;
2893
2894         /* file_mask_to_av won't add FILE__WRITE if MAY_APPEND is set */
2895         if ((file->f_flags & O_APPEND) && (mask & MAY_WRITE))
2896                 mask |= MAY_APPEND;
2897
2898         return file_has_perm(cred, file,
2899                              file_mask_to_av(inode->i_mode, mask));
2900 }
2901
2902 static int selinux_file_permission(struct file *file, int mask)
2903 {
2904         struct inode *inode = file->f_path.dentry->d_inode;
2905         struct file_security_struct *fsec = file->f_security;
2906         struct inode_security_struct *isec = inode->i_security;
2907         u32 sid = current_sid();
2908
2909         if (!mask)
2910                 /* No permission to check.  Existence test. */
2911                 return 0;
2912
2913         if (sid == fsec->sid && fsec->isid == isec->sid &&
2914             fsec->pseqno == avc_policy_seqno())
2915                 /* No change since dentry_open check. */
2916                 return 0;
2917
2918         return selinux_revalidate_file_permission(file, mask);
2919 }
2920
2921 static int selinux_file_alloc_security(struct file *file)
2922 {
2923         return file_alloc_security(file);
2924 }
2925
2926 static void selinux_file_free_security(struct file *file)
2927 {
2928         file_free_security(file);
2929 }
2930
2931 static int selinux_file_ioctl(struct file *file, unsigned int cmd,
2932                               unsigned long arg)
2933 {
2934         const struct cred *cred = current_cred();
2935         u32 av = 0;
2936
2937         if (_IOC_DIR(cmd) & _IOC_WRITE)
2938                 av |= FILE__WRITE;
2939         if (_IOC_DIR(cmd) & _IOC_READ)
2940                 av |= FILE__READ;
2941         if (!av)
2942                 av = FILE__IOCTL;
2943
2944         return file_has_perm(cred, file, av);
2945 }
2946
2947 static int default_noexec;
2948
2949 static int file_map_prot_check(struct file *file, unsigned long prot, int shared)
2950 {
2951         const struct cred *cred = current_cred();
2952         int rc = 0;
2953
2954         if (default_noexec &&
2955             (prot & PROT_EXEC) && (!file || (!shared && (prot & PROT_WRITE)))) {
2956                 /*
2957                  * We are making executable an anonymous mapping or a
2958                  * private file mapping that will also be writable.
2959                  * This has an additional check.
2960                  */
2961                 rc = cred_has_perm(cred, cred, PROCESS__EXECMEM);
2962                 if (rc)
2963                         goto error;
2964         }
2965
2966         if (file) {
2967                 /* read access is always possible with a mapping */
2968                 u32 av = FILE__READ;
2969
2970                 /* write access only matters if the mapping is shared */
2971                 if (shared && (prot & PROT_WRITE))
2972                         av |= FILE__WRITE;
2973
2974                 if (prot & PROT_EXEC)
2975                         av |= FILE__EXECUTE;
2976
2977                 return file_has_perm(cred, file, av);
2978         }
2979
2980 error:
2981         return rc;
2982 }
2983
2984 static int selinux_file_mmap(struct file *file, unsigned long reqprot,
2985                              unsigned long prot, unsigned long flags,
2986                              unsigned long addr, unsigned long addr_only)
2987 {
2988         int rc = 0;
2989         u32 sid = current_sid();
2990
2991         /*
2992          * notice that we are intentionally putting the SELinux check before
2993          * the secondary cap_file_mmap check.  This is such a likely attempt
2994          * at bad behaviour/exploit that we always want to get the AVC, even
2995          * if DAC would have also denied the operation.
2996          */
2997         if (addr < CONFIG_LSM_MMAP_MIN_ADDR) {
2998                 rc = avc_has_perm(sid, sid, SECCLASS_MEMPROTECT,
2999                                   MEMPROTECT__MMAP_ZERO, NULL);
3000                 if (rc)
3001                         return rc;
3002         }
3003
3004         /* do DAC check on address space usage */
3005         rc = cap_file_mmap(file, reqprot, prot, flags, addr, addr_only);
3006         if (rc || addr_only)
3007                 return rc;
3008
3009         if (selinux_checkreqprot)
3010                 prot = reqprot;
3011
3012         return file_map_prot_check(file, prot,
3013                                    (flags & MAP_TYPE) == MAP_SHARED);
3014 }
3015
3016 static int selinux_file_mprotect(struct vm_area_struct *vma,
3017                                  unsigned long reqprot,
3018                                  unsigned long prot)
3019 {
3020         const struct cred *cred = current_cred();
3021
3022         if (selinux_checkreqprot)
3023                 prot = reqprot;
3024
3025         if (default_noexec &&
3026             (prot & PROT_EXEC) && !(vma->vm_flags & VM_EXEC)) {
3027                 int rc = 0;
3028                 if (vma->vm_start >= vma->vm_mm->start_brk &&
3029                     vma->vm_end <= vma->vm_mm->brk) {
3030                         rc = cred_has_perm(cred, cred, PROCESS__EXECHEAP);
3031                 } else if (!vma->vm_file &&
3032                            vma->vm_start <= vma->vm_mm->start_stack &&
3033                            vma->vm_end >= vma->vm_mm->start_stack) {
3034                         rc = current_has_perm(current, PROCESS__EXECSTACK);
3035                 } else if (vma->vm_file && vma->anon_vma) {
3036                         /*
3037                          * We are making executable a file mapping that has
3038                          * had some COW done. Since pages might have been
3039                          * written, check ability to execute the possibly
3040                          * modified content.  This typically should only
3041                          * occur for text relocations.
3042                          */
3043                         rc = file_has_perm(cred, vma->vm_file, FILE__EXECMOD);
3044                 }
3045                 if (rc)
3046                         return rc;
3047         }
3048
3049         return file_map_prot_check(vma->vm_file, prot, vma->vm_flags&VM_SHARED);
3050 }
3051
3052 static int selinux_file_lock(struct file *file, unsigned int cmd)
3053 {
3054         const struct cred *cred = current_cred();
3055
3056         return file_has_perm(cred, file, FILE__LOCK);
3057 }
3058
3059 static int selinux_file_fcntl(struct file *file, unsigned int cmd,
3060                               unsigned long arg)
3061 {
3062         const struct cred *cred = current_cred();
3063         int err = 0;
3064
3065         switch (cmd) {
3066         case F_SETFL:
3067                 if (!file->f_path.dentry || !file->f_path.dentry->d_inode) {
3068                         err = -EINVAL;
3069                         break;
3070                 }
3071
3072                 if ((file->f_flags & O_APPEND) && !(arg & O_APPEND)) {
3073                         err = file_has_perm(cred, file, FILE__WRITE);
3074                         break;
3075                 }
3076                 /* fall through */
3077         case F_SETOWN:
3078         case F_SETSIG:
3079         case F_GETFL:
3080         case F_GETOWN:
3081         case F_GETSIG:
3082                 /* Just check FD__USE permission */
3083                 err = file_has_perm(cred, file, 0);
3084                 break;
3085         case F_GETLK:
3086         case F_SETLK:
3087         case F_SETLKW:
3088 #if BITS_PER_LONG == 32
3089         case F_GETLK64:
3090         case F_SETLK64:
3091         case F_SETLKW64:
3092 #endif
3093                 if (!file->f_path.dentry || !file->f_path.dentry->d_inode) {
3094                         err = -EINVAL;
3095                         break;
3096                 }
3097                 err = file_has_perm(cred, file, FILE__LOCK);
3098                 break;
3099         }
3100
3101         return err;
3102 }
3103
3104 static int selinux_file_set_fowner(struct file *file)
3105 {
3106         struct file_security_struct *fsec;
3107
3108         fsec = file->f_security;
3109         fsec->fown_sid = current_sid();
3110
3111         return 0;
3112 }
3113
3114 static int selinux_file_send_sigiotask(struct task_struct *tsk,
3115                                        struct fown_struct *fown, int signum)
3116 {
3117         struct file *file;
3118         u32 sid = task_sid(tsk);
3119         u32 perm;
3120         struct file_security_struct *fsec;
3121
3122         /* struct fown_struct is never outside the context of a struct file */
3123         file = container_of(fown, struct file, f_owner);
3124
3125         fsec = file->f_security;
3126
3127         if (!signum)
3128                 perm = signal_to_av(SIGIO); /* as per send_sigio_to_task */
3129         else
3130                 perm = signal_to_av(signum);
3131
3132         return avc_has_perm(fsec->fown_sid, sid,
3133                             SECCLASS_PROCESS, perm, NULL);
3134 }
3135
3136 static int selinux_file_receive(struct file *file)
3137 {
3138         const struct cred *cred = current_cred();
3139
3140         return file_has_perm(cred, file, file_to_av(file));
3141 }
3142
3143 static int selinux_dentry_open(struct file *file, const struct cred *cred)
3144 {
3145         struct file_security_struct *fsec;
3146         struct inode *inode;
3147         struct inode_security_struct *isec;
3148
3149         inode = file->f_path.dentry->d_inode;
3150         fsec = file->f_security;
3151         isec = inode->i_security;
3152         /*
3153          * Save inode label and policy sequence number
3154          * at open-time so that selinux_file_permission
3155          * can determine whether revalidation is necessary.
3156          * Task label is already saved in the file security
3157          * struct as its SID.
3158          */
3159         fsec->isid = isec->sid;
3160         fsec->pseqno = avc_policy_seqno();
3161         /*
3162          * Since the inode label or policy seqno may have changed
3163          * between the selinux_inode_permission check and the saving
3164          * of state above, recheck that access is still permitted.
3165          * Otherwise, access might never be revalidated against the
3166          * new inode label or new policy.
3167          * This check is not redundant - do not remove.
3168          */
3169         return inode_has_perm(cred, inode, open_file_to_av(file), NULL);
3170 }
3171
3172 /* task security operations */
3173
3174 static int selinux_task_create(unsigned long clone_flags)
3175 {
3176         return current_has_perm(current, PROCESS__FORK);
3177 }
3178
3179 /*
3180  * allocate the SELinux part of blank credentials
3181  */
3182 static int selinux_cred_alloc_blank(struct cred *cred, gfp_t gfp)
3183 {
3184         struct task_security_struct *tsec;
3185
3186         tsec = kzalloc(sizeof(struct task_security_struct), gfp);
3187         if (!tsec)
3188                 return -ENOMEM;
3189
3190         cred->security = tsec;
3191         return 0;
3192 }
3193
3194 /*
3195  * detach and free the LSM part of a set of credentials
3196  */
3197 static void selinux_cred_free(struct cred *cred)
3198 {
3199         struct task_security_struct *tsec = cred->security;
3200
3201         BUG_ON((unsigned long) cred->security < PAGE_SIZE);
3202         cred->security = (void *) 0x7UL;
3203         kfree(tsec);
3204 }
3205
3206 /*
3207  * prepare a new set of credentials for modification
3208  */
3209 static int selinux_cred_prepare(struct cred *new, const struct cred *old,
3210                                 gfp_t gfp)
3211 {
3212         const struct task_security_struct *old_tsec;
3213         struct task_security_struct *tsec;
3214
3215         old_tsec = old->security;
3216
3217         tsec = kmemdup(old_tsec, sizeof(struct task_security_struct), gfp);
3218         if (!tsec)
3219                 return -ENOMEM;
3220
3221         new->security = tsec;
3222         return 0;
3223 }
3224
3225 /*
3226  * transfer the SELinux data to a blank set of creds
3227  */
3228 static void selinux_cred_transfer(struct cred *new, const struct cred *old)
3229 {
3230         const struct task_security_struct *old_tsec = old->security;
3231         struct task_security_struct *tsec = new->security;
3232
3233         *tsec = *old_tsec;
3234 }
3235
3236 /*
3237  * set the security data for a kernel service
3238  * - all the creation contexts are set to unlabelled
3239  */
3240 static int selinux_kernel_act_as(struct cred *new, u32 secid)
3241 {
3242         struct task_security_struct *tsec = new->security;
3243         u32 sid = current_sid();
3244         int ret;
3245
3246         ret = avc_has_perm(sid, secid,
3247                            SECCLASS_KERNEL_SERVICE,
3248                            KERNEL_SERVICE__USE_AS_OVERRIDE,
3249                            NULL);
3250         if (ret == 0) {
3251                 tsec->sid = secid;
3252                 tsec->create_sid = 0;
3253                 tsec->keycreate_sid = 0;
3254                 tsec->sockcreate_sid = 0;
3255         }
3256         return ret;
3257 }
3258
3259 /*
3260  * set the file creation context in a security record to the same as the
3261  * objective context of the specified inode
3262  */
3263 static int selinux_kernel_create_files_as(struct cred *new, struct inode *inode)
3264 {
3265         struct inode_security_struct *isec = inode->i_security;
3266         struct task_security_struct *tsec = new->security;
3267         u32 sid = current_sid();
3268         int ret;
3269
3270         ret = avc_has_perm(sid, isec->sid,
3271                            SECCLASS_KERNEL_SERVICE,
3272                            KERNEL_SERVICE__CREATE_FILES_AS,
3273                            NULL);
3274
3275         if (ret == 0)
3276                 tsec->create_sid = isec->sid;
3277         return ret;
3278 }
3279
3280 static int selinux_kernel_module_request(char *kmod_name)
3281 {
3282         u32 sid;
3283         struct common_audit_data ad;
3284
3285         sid = task_sid(current);
3286
3287         COMMON_AUDIT_DATA_INIT(&ad, KMOD);
3288         ad.u.kmod_name = kmod_name;
3289
3290         return avc_has_perm(sid, SECINITSID_KERNEL, SECCLASS_SYSTEM,
3291                             SYSTEM__MODULE_REQUEST, &ad);
3292 }
3293
3294 static int selinux_task_setpgid(struct task_struct *p, pid_t pgid)
3295 {
3296         return current_has_perm(p, PROCESS__SETPGID);
3297 }
3298
3299 static int selinux_task_getpgid(struct task_struct *p)
3300 {
3301         return current_has_perm(p, PROCESS__GETPGID);
3302 }
3303
3304 static int selinux_task_getsid(struct task_struct *p)
3305 {
3306         return current_has_perm(p, PROCESS__GETSESSION);
3307 }
3308
3309 static void selinux_task_getsecid(struct task_struct *p, u32 *secid)
3310 {
3311         *secid = task_sid(p);
3312 }
3313
3314 static int selinux_task_setnice(struct task_struct *p, int nice)
3315 {
3316         int rc;
3317
3318         rc = cap_task_setnice(p, nice);
3319         if (rc)
3320                 return rc;
3321
3322         return current_has_perm(p, PROCESS__SETSCHED);
3323 }
3324
3325 static int selinux_task_setioprio(struct task_struct *p, int ioprio)
3326 {
3327         int rc;
3328
3329         rc = cap_task_setioprio(p, ioprio);
3330         if (rc)
3331                 return rc;
3332
3333         return current_has_perm(p, PROCESS__SETSCHED);
3334 }
3335
3336 static int selinux_task_getioprio(struct task_struct *p)
3337 {
3338         return current_has_perm(p, PROCESS__GETSCHED);
3339 }
3340
3341 static int selinux_task_setrlimit(struct task_struct *p, unsigned int resource,
3342                 struct rlimit *new_rlim)
3343 {
3344         struct rlimit *old_rlim = p->signal->rlim + resource;
3345
3346         /* Control the ability to change the hard limit (whether
3347            lowering or raising it), so that the hard limit can
3348            later be used as a safe reset point for the soft limit
3349            upon context transitions.  See selinux_bprm_committing_creds. */
3350         if (old_rlim->rlim_max != new_rlim->rlim_max)
3351                 return current_has_perm(p, PROCESS__SETRLIMIT);
3352
3353         return 0;
3354 }
3355
3356 static int selinux_task_setscheduler(struct task_struct *p)
3357 {
3358         int rc;
3359
3360         rc = cap_task_setscheduler(p);
3361         if (rc)
3362                 return rc;
3363
3364         return current_has_perm(p, PROCESS__SETSCHED);
3365 }
3366
3367 static int selinux_task_getscheduler(struct task_struct *p)
3368 {
3369         return current_has_perm(p, PROCESS__GETSCHED);
3370 }
3371
3372 static int selinux_task_movememory(struct task_struct *p)
3373 {
3374         return current_has_perm(p, PROCESS__SETSCHED);
3375 }
3376
3377 static int selinux_task_kill(struct task_struct *p, struct siginfo *info,
3378                                 int sig, u32 secid)
3379 {
3380         u32 perm;
3381         int rc;
3382
3383         if (!sig)
3384                 perm = PROCESS__SIGNULL; /* null signal; existence test */
3385         else
3386                 perm = signal_to_av(sig);
3387         if (secid)
3388                 rc = avc_has_perm(secid, task_sid(p),
3389                                   SECCLASS_PROCESS, perm, NULL);
3390         else
3391                 rc = current_has_perm(p, perm);
3392         return rc;
3393 }
3394
3395 static int selinux_task_wait(struct task_struct *p)
3396 {
3397         return task_has_perm(p, current, PROCESS__SIGCHLD);
3398 }
3399
3400 static void selinux_task_to_inode(struct task_struct *p,
3401                                   struct inode *inode)
3402 {
3403         struct inode_security_struct *isec = inode->i_security;
3404         u32 sid = task_sid(p);
3405
3406         isec->sid = sid;
3407         isec->initialized = 1;
3408 }
3409
3410 /* Returns error only if unable to parse addresses */
3411 static int selinux_parse_skb_ipv4(struct sk_buff *skb,
3412                         struct common_audit_data *ad, u8 *proto)
3413 {
3414         int offset, ihlen, ret = -EINVAL;
3415         struct iphdr _iph, *ih;
3416
3417         offset = skb_network_offset(skb);
3418         ih = skb_header_pointer(skb, offset, sizeof(_iph), &_iph);
3419         if (ih == NULL)
3420                 goto out;
3421
3422         ihlen = ih->ihl * 4;
3423         if (ihlen < sizeof(_iph))
3424                 goto out;
3425
3426         ad->u.net.v4info.saddr = ih->saddr;
3427         ad->u.net.v4info.daddr = ih->daddr;
3428         ret = 0;
3429
3430         if (proto)
3431                 *proto = ih->protocol;
3432
3433         switch (ih->protocol) {
3434         case IPPROTO_TCP: {
3435                 struct tcphdr _tcph, *th;
3436
3437                 if (ntohs(ih->frag_off) & IP_OFFSET)
3438                         break;
3439
3440                 offset += ihlen;
3441                 th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph);
3442                 if (th == NULL)
3443                         break;
3444
3445                 ad->u.net.sport = th->source;
3446                 ad->u.net.dport = th->dest;
3447                 break;
3448         }
3449
3450         case IPPROTO_UDP: {
3451                 struct udphdr _udph, *uh;
3452
3453                 if (ntohs(ih->frag_off) & IP_OFFSET)
3454                         break;
3455
3456                 offset += ihlen;
3457                 uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph);
3458                 if (uh == NULL)
3459                         break;
3460
3461                 ad->u.net.sport = uh->source;
3462                 ad->u.net.dport = uh->dest;
3463                 break;
3464         }
3465
3466         case IPPROTO_DCCP: {
3467                 struct dccp_hdr _dccph, *dh;
3468
3469                 if (ntohs(ih->frag_off) & IP_OFFSET)
3470                         break;
3471
3472                 offset += ihlen;
3473                 dh = skb_header_pointer(skb, offset, sizeof(_dccph), &_dccph);
3474                 if (dh == NULL)
3475                         break;
3476
3477                 ad->u.net.sport = dh->dccph_sport;
3478                 ad->u.net.dport = dh->dccph_dport;
3479                 break;
3480         }
3481
3482         default:
3483                 break;
3484         }
3485 out:
3486         return ret;
3487 }
3488
3489 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
3490
3491 /* Returns error only if unable to parse addresses */
3492 static int selinux_parse_skb_ipv6(struct sk_buff *skb,
3493                         struct common_audit_data *ad, u8 *proto)
3494 {
3495         u8 nexthdr;
3496         int ret = -EINVAL, offset;
3497         struct ipv6hdr _ipv6h, *ip6;
3498
3499         offset = skb_network_offset(skb);
3500         ip6 = skb_header_pointer(skb, offset, sizeof(_ipv6h), &_ipv6h);
3501         if (ip6 == NULL)
3502                 goto out;
3503
3504         ipv6_addr_copy(&ad->u.net.v6info.saddr, &ip6->saddr);
3505         ipv6_addr_copy(&ad->u.net.v6info.daddr, &ip6->daddr);
3506         ret = 0;
3507
3508         nexthdr = ip6->nexthdr;
3509         offset += sizeof(_ipv6h);
3510         offset = ipv6_skip_exthdr(skb, offset, &nexthdr);
3511         if (offset < 0)
3512                 goto out;
3513
3514         if (proto)
3515                 *proto = nexthdr;
3516
3517         switch (nexthdr) {
3518         case IPPROTO_TCP: {
3519                 struct tcphdr _tcph, *th;
3520
3521                 th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph);
3522                 if (th == NULL)
3523                         break;
3524
3525                 ad->u.net.sport = th->source;
3526                 ad->u.net.dport = th->dest;
3527                 break;
3528         }
3529
3530         case IPPROTO_UDP: {
3531                 struct udphdr _udph, *uh;
3532
3533                 uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph);
3534                 if (uh == NULL)
3535                         break;
3536
3537                 ad->u.net.sport = uh->source;
3538                 ad->u.net.dport = uh->dest;
3539                 break;
3540         }
3541
3542         case IPPROTO_DCCP: {
3543                 struct dccp_hdr _dccph, *dh;
3544
3545                 dh = skb_header_pointer(skb, offset, sizeof(_dccph), &_dccph);
3546                 if (dh == NULL)
3547                         break;
3548
3549                 ad->u.net.sport = dh->dccph_sport;
3550                 ad->u.net.dport = dh->dccph_dport;
3551                 break;
3552         }
3553
3554         /* includes fragments */
3555         default:
3556                 break;
3557         }
3558 out:
3559         return ret;
3560 }
3561
3562 #endif /* IPV6 */
3563
3564 static int selinux_parse_skb(struct sk_buff *skb, struct common_audit_data *ad,
3565                              char **_addrp, int src, u8 *proto)
3566 {
3567         char *addrp;
3568         int ret;
3569
3570         switch (ad->u.net.family) {
3571         case PF_INET:
3572                 ret = selinux_parse_skb_ipv4(skb, ad, proto);
3573                 if (ret)
3574                         goto parse_error;
3575                 addrp = (char *)(src ? &ad->u.net.v4info.saddr :
3576                                        &ad->u.net.v4info.daddr);
3577                 goto okay;
3578
3579 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
3580         case PF_INET6:
3581                 ret = selinux_parse_skb_ipv6(skb, ad, proto);
3582                 if (ret)
3583                         goto parse_error;
3584                 addrp = (char *)(src ? &ad->u.net.v6info.saddr :
3585                                        &ad->u.net.v6info.daddr);
3586                 goto okay;
3587 #endif  /* IPV6 */
3588         default:
3589                 addrp = NULL;
3590                 goto okay;
3591         }
3592
3593 parse_error:
3594         printk(KERN_WARNING
3595                "SELinux: failure in selinux_parse_skb(),"
3596                " unable to parse packet\n");
3597         return ret;
3598
3599 okay:
3600         if (_addrp)
3601                 *_addrp = addrp;
3602         return 0;
3603 }
3604
3605 /**
3606  * selinux_skb_peerlbl_sid - Determine the peer label of a packet
3607  * @skb: the packet
3608  * @family: protocol family
3609  * @sid: the packet's peer label SID
3610  *
3611  * Description:
3612  * Check the various different forms of network peer labeling and determine
3613  * the peer label/SID for the packet; most of the magic actually occurs in
3614  * the security server function security_net_peersid_cmp().  The function
3615  * returns zero if the value in @sid is valid (although it may be SECSID_NULL)
3616  * or -EACCES if @sid is invalid due to inconsistencies with the different
3617  * peer labels.
3618  *
3619  */
3620 static int selinux_skb_peerlbl_sid(struct sk_buff *skb, u16 family, u32 *sid)
3621 {
3622         int err;
3623         u32 xfrm_sid;
3624         u32 nlbl_sid;
3625         u32 nlbl_type;
3626
3627         selinux_skb_xfrm_sid(skb, &xfrm_sid);
3628         selinux_netlbl_skbuff_getsid(skb, family, &nlbl_type, &nlbl_sid);
3629
3630         err = security_net_peersid_resolve(nlbl_sid, nlbl_type, xfrm_sid, sid);
3631         if (unlikely(err)) {
3632                 printk(KERN_WARNING
3633                        "SELinux: failure in selinux_skb_peerlbl_sid(),"
3634                        " unable to determine packet's peer label\n");
3635                 return -EACCES;
3636         }
3637
3638         return 0;
3639 }
3640
3641 /* socket security operations */
3642
3643 static u32 socket_sockcreate_sid(const struct task_security_struct *tsec)
3644 {
3645         return tsec->sockcreate_sid ? : tsec->sid;
3646 }
3647
3648 static int sock_has_perm(struct task_struct *task, struct sock *sk, u32 perms)
3649 {
3650         struct sk_security_struct *sksec = sk->sk_security;
3651         struct common_audit_data ad;
3652         u32 tsid = task_sid(task);
3653
3654         if (sksec->sid == SECINITSID_KERNEL)
3655                 return 0;
3656
3657         COMMON_AUDIT_DATA_INIT(&ad, NET);
3658         ad.u.net.sk = sk;
3659
3660         return avc_has_perm(tsid, sksec->sid, sksec->sclass, perms, &ad);
3661 }
3662
3663 static int selinux_socket_create(int family, int type,
3664                                  int protocol, int kern)
3665 {
3666         const struct task_security_struct *tsec = current_security();
3667         u32 newsid;
3668         u16 secclass;
3669
3670         if (kern)
3671                 return 0;
3672
3673         newsid = socket_sockcreate_sid(tsec);
3674         secclass = socket_type_to_security_class(family, type, protocol);
3675         return avc_has_perm(tsec->sid, newsid, secclass, SOCKET__CREATE, NULL);
3676 }
3677
3678 static int selinux_socket_post_create(struct socket *sock, int family,
3679                                       int type, int protocol, int kern)
3680 {
3681         const struct task_security_struct *tsec = current_security();
3682         struct inode_security_struct *isec = SOCK_INODE(sock)->i_security;
3683         struct sk_security_struct *sksec;
3684         int err = 0;
3685
3686         if (kern)
3687                 isec->sid = SECINITSID_KERNEL;
3688         else
3689                 isec->sid = socket_sockcreate_sid(tsec);
3690
3691         isec->sclass = socket_type_to_security_class(family, type, protocol);
3692         isec->initialized = 1;
3693
3694         if (sock->sk) {
3695                 sksec = sock->sk->sk_security;
3696                 sksec->sid = isec->sid;
3697                 sksec->sclass = isec->sclass;
3698                 err = selinux_netlbl_socket_post_create(sock->sk, family);
3699         }
3700
3701         return err;
3702 }
3703
3704 /* Range of port numbers used to automatically bind.
3705    Need to determine whether we should perform a name_bind
3706    permission check between the socket and the port number. */
3707
3708 static int selinux_socket_bind(struct socket *sock, struct sockaddr *address, int addrlen)
3709 {
3710         struct sock *sk = sock->sk;
3711         u16 family;
3712         int err;
3713
3714         err = sock_has_perm(current, sk, SOCKET__BIND);
3715         if (err)
3716                 goto out;
3717
3718         /*
3719          * If PF_INET or PF_INET6, check name_bind permission for the port.
3720          * Multiple address binding for SCTP is not supported yet: we just
3721          * check the first address now.
3722          */
3723         family = sk->sk_family;
3724         if (family == PF_INET || family == PF_INET6) {
3725                 char *addrp;
3726                 struct sk_security_struct *sksec = sk->sk_security;
3727                 struct common_audit_data ad;
3728                 struct sockaddr_in *addr4 = NULL;
3729                 struct sockaddr_in6 *addr6 = NULL;
3730                 unsigned short snum;
3731                 u32 sid, node_perm;
3732
3733                 if (family == PF_INET) {
3734                         addr4 = (struct sockaddr_in *)address;
3735                         snum = ntohs(addr4->sin_port);
3736                         addrp = (char *)&addr4->sin_addr.s_addr;
3737                 } else {
3738                         addr6 = (struct sockaddr_in6 *)address;
3739                         snum = ntohs(addr6->sin6_port);
3740                         addrp = (char *)&addr6->sin6_addr.s6_addr;
3741                 }
3742
3743                 if (snum) {
3744                         int low, high;
3745
3746                         inet_get_local_port_range(&low, &high);
3747
3748                         if (snum < max(PROT_SOCK, low) || snum > high) {
3749                                 err = sel_netport_sid(sk->sk_protocol,
3750                                                       snum, &sid);
3751                                 if (err)
3752                                         goto out;
3753                                 COMMON_AUDIT_DATA_INIT(&ad, NET);
3754                                 ad.u.net.sport = htons(snum);
3755                                 ad.u.net.family = family;
3756                                 err = avc_has_perm(sksec->sid, sid,
3757                                                    sksec->sclass,
3758                                                    SOCKET__NAME_BIND, &ad);
3759                                 if (err)
3760                                         goto out;
3761                         }
3762                 }
3763
3764                 switch (sksec->sclass) {
3765                 case SECCLASS_TCP_SOCKET:
3766                         node_perm = TCP_SOCKET__NODE_BIND;
3767                         break;
3768
3769                 case SECCLASS_UDP_SOCKET:
3770                         node_perm = UDP_SOCKET__NODE_BIND;
3771                         break;
3772
3773                 case SECCLASS_DCCP_SOCKET:
3774                         node_perm = DCCP_SOCKET__NODE_BIND;
3775                         break;
3776
3777                 default:
3778                         node_perm = RAWIP_SOCKET__NODE_BIND;
3779                         break;
3780                 }
3781
3782                 err = sel_netnode_sid(addrp, family, &sid);
3783                 if (err)
3784                         goto out;
3785
3786                 COMMON_AUDIT_DATA_INIT(&ad, NET);
3787                 ad.u.net.sport = htons(snum);
3788                 ad.u.net.family = family;
3789
3790                 if (family == PF_INET)
3791                         ad.u.net.v4info.saddr = addr4->sin_addr.s_addr;
3792                 else
3793                         ipv6_addr_copy(&ad.u.net.v6info.saddr, &addr6->sin6_addr);
3794
3795                 err = avc_has_perm(sksec->sid, sid,
3796                                    sksec->sclass, node_perm, &ad);
3797                 if (err)
3798                         goto out;
3799         }
3800 out:
3801         return err;
3802 }
3803
3804 static int selinux_socket_connect(struct socket *sock, struct sockaddr *address, int addrlen)
3805 {
3806         struct sock *sk = sock->sk;
3807         struct sk_security_struct *sksec = sk->sk_security;
3808         int err;
3809
3810         err = sock_has_perm(current, sk, SOCKET__CONNECT);
3811         if (err)
3812                 return err;
3813
3814         /*
3815          * If a TCP or DCCP socket, check name_connect permission for the port.
3816          */
3817         if (sksec->sclass == SECCLASS_TCP_SOCKET ||
3818             sksec->sclass == SECCLASS_DCCP_SOCKET) {
3819                 struct common_audit_data ad;
3820                 struct sockaddr_in *addr4 = NULL;
3821                 struct sockaddr_in6 *addr6 = NULL;
3822                 unsigned short snum;
3823                 u32 sid, perm;
3824
3825                 if (sk->sk_family == PF_INET) {
3826                         addr4 = (struct sockaddr_in *)address;
3827                         if (addrlen < sizeof(struct sockaddr_in))
3828                                 return -EINVAL;
3829                         snum = ntohs(addr4->sin_port);
3830                 } else {
3831                         addr6 = (struct sockaddr_in6 *)address;
3832                         if (addrlen < SIN6_LEN_RFC2133)
3833                                 return -EINVAL;
3834                         snum = ntohs(addr6->sin6_port);
3835                 }
3836
3837                 err = sel_netport_sid(sk->sk_protocol, snum, &sid);
3838                 if (err)
3839                         goto out;
3840
3841                 perm = (sksec->sclass == SECCLASS_TCP_SOCKET) ?
3842                        TCP_SOCKET__NAME_CONNECT : DCCP_SOCKET__NAME_CONNECT;
3843
3844                 COMMON_AUDIT_DATA_INIT(&ad, NET);
3845                 ad.u.net.dport = htons(snum);
3846                 ad.u.net.family = sk->sk_family;
3847                 err = avc_has_perm(sksec->sid, sid, sksec->sclass, perm, &ad);
3848                 if (err)
3849                         goto out;
3850         }
3851
3852         err = selinux_netlbl_socket_connect(sk, address);
3853
3854 out:
3855         return err;
3856 }
3857
3858 static int selinux_socket_listen(struct socket *sock, int backlog)
3859 {
3860         return sock_has_perm(current, sock->sk, SOCKET__LISTEN);
3861 }
3862
3863 static int selinux_socket_accept(struct socket *sock, struct socket *newsock)
3864 {
3865         int err;
3866         struct inode_security_struct *isec;
3867         struct inode_security_struct *newisec;
3868
3869         err = sock_has_perm(current, sock->sk, SOCKET__ACCEPT);
3870         if (err)
3871                 return err;
3872
3873         newisec = SOCK_INODE(newsock)->i_security;
3874
3875         isec = SOCK_INODE(sock)->i_security;
3876         newisec->sclass = isec->sclass;
3877         newisec->sid = isec->sid;
3878         newisec->initialized = 1;
3879
3880         return 0;
3881 }
3882
3883 static int selinux_socket_sendmsg(struct socket *sock, struct msghdr *msg,
3884                                   int size)
3885 {
3886         return sock_has_perm(current, sock->sk, SOCKET__WRITE);
3887 }
3888
3889 static int selinux_socket_recvmsg(struct socket *sock, struct msghdr *msg,
3890                                   int size, int flags)
3891 {
3892         return sock_has_perm(current, sock->sk, SOCKET__READ);
3893 }
3894
3895 static int selinux_socket_getsockname(struct socket *sock)
3896 {
3897         return sock_has_perm(current, sock->sk, SOCKET__GETATTR);
3898 }
3899
3900 static int selinux_socket_getpeername(struct socket *sock)
3901 {
3902         return sock_has_perm(current, sock->sk, SOCKET__GETATTR);
3903 }
3904
3905 static int selinux_socket_setsockopt(struct socket *sock, int level, int optname)
3906 {
3907         int err;
3908
3909         err = sock_has_perm(current, sock->sk, SOCKET__SETOPT);
3910         if (err)
3911                 return err;
3912
3913         return selinux_netlbl_socket_setsockopt(sock, level, optname);
3914 }
3915
3916 static int selinux_socket_getsockopt(struct socket *sock, int level,
3917                                      int optname)
3918 {
3919         return sock_has_perm(current, sock->sk, SOCKET__GETOPT);
3920 }
3921
3922 static int selinux_socket_shutdown(struct socket *sock, int how)
3923 {
3924         return sock_has_perm(current, sock->sk, SOCKET__SHUTDOWN);
3925 }
3926
3927 static int selinux_socket_unix_stream_connect(struct sock *sock,
3928                                               struct sock *other,
3929                                               struct sock *newsk)
3930 {
3931         struct sk_security_struct *sksec_sock = sock->sk_security;
3932         struct sk_security_struct *sksec_other = other->sk_security;
3933         struct sk_security_struct *sksec_new = newsk->sk_security;
3934         struct common_audit_data ad;
3935         int err;
3936
3937         COMMON_AUDIT_DATA_INIT(&ad, NET);
3938         ad.u.net.sk = other;
3939
3940         err = avc_has_perm(sksec_sock->sid, sksec_other->sid,
3941                            sksec_other->sclass,
3942                            UNIX_STREAM_SOCKET__CONNECTTO, &ad);
3943         if (err)
3944                 return err;
3945
3946         /* server child socket */
3947         sksec_new->peer_sid = sksec_sock->sid;
3948         err = security_sid_mls_copy(sksec_other->sid, sksec_sock->sid,
3949                                     &sksec_new->sid);
3950         if (err)
3951                 return err;
3952
3953         /* connecting socket */
3954         sksec_sock->peer_sid = sksec_new->sid;
3955
3956         return 0;
3957 }
3958
3959 static int selinux_socket_unix_may_send(struct socket *sock,
3960                                         struct socket *other)
3961 {
3962         struct sk_security_struct *ssec = sock->sk->sk_security;
3963         struct sk_security_struct *osec = other->sk->sk_security;
3964         struct common_audit_data ad;
3965
3966         COMMON_AUDIT_DATA_INIT(&ad, NET);
3967         ad.u.net.sk = other->sk;
3968
3969         return avc_has_perm(ssec->sid, osec->sid, osec->sclass, SOCKET__SENDTO,
3970                             &ad);
3971 }
3972
3973 static int selinux_inet_sys_rcv_skb(int ifindex, char *addrp, u16 family,
3974                                     u32 peer_sid,
3975                                     struct common_audit_data *ad)
3976 {
3977         int err;
3978         u32 if_sid;
3979         u32 node_sid;
3980
3981         err = sel_netif_sid(ifindex, &if_sid);
3982         if (err)
3983                 return err;
3984         err = avc_has_perm(peer_sid, if_sid,
3985                            SECCLASS_NETIF, NETIF__INGRESS, ad);
3986         if (err)
3987                 return err;
3988
3989         err = sel_netnode_sid(addrp, family, &node_sid);
3990         if (err)
3991                 return err;
3992         return avc_has_perm(peer_sid, node_sid,
3993                             SECCLASS_NODE, NODE__RECVFROM, ad);
3994 }
3995
3996 static int selinux_sock_rcv_skb_compat(struct sock *sk, struct sk_buff *skb,
3997                                        u16 family)
3998 {
3999         int err = 0;
4000         struct sk_security_struct *sksec = sk->sk_security;
4001         u32 peer_sid;
4002         u32 sk_sid = sksec->sid;
4003         struct common_audit_data ad;
4004         char *addrp;
4005
4006         COMMON_AUDIT_DATA_INIT(&ad, NET);
4007         ad.u.net.netif = skb->skb_iif;
4008         ad.u.net.family = family;
4009         err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL);
4010         if (err)
4011                 return err;
4012
4013         if (selinux_secmark_enabled()) {
4014                 err = avc_has_perm(sk_sid, skb->secmark, SECCLASS_PACKET,
4015                                    PACKET__RECV, &ad);
4016                 if (err)
4017                         return err;
4018         }
4019
4020         if (selinux_policycap_netpeer) {
4021                 err = selinux_skb_peerlbl_sid(skb, family, &peer_sid);
4022                 if (err)
4023                         return err;
4024                 err = avc_has_perm(sk_sid, peer_sid,
4025                                    SECCLASS_PEER, PEER__RECV, &ad);
4026                 if (err)
4027                         selinux_netlbl_err(skb, err, 0);
4028         } else {
4029                 err = selinux_netlbl_sock_rcv_skb(sksec, skb, family, &ad);
4030                 if (err)
4031                         return err;
4032                 err = selinux_xfrm_sock_rcv_skb(sksec->sid, skb, &ad);
4033         }
4034
4035         return err;
4036 }
4037
4038 static int selinux_socket_sock_rcv_skb(struct sock *sk, struct sk_buff *skb)
4039 {
4040         int err;
4041         struct sk_security_struct *sksec = sk->sk_security;
4042         u16 family = sk->sk_family;
4043         u32 sk_sid = sksec->sid;
4044         struct common_audit_data ad;
4045         char *addrp;
4046         u8 secmark_active;
4047         u8 peerlbl_active;
4048
4049         if (family != PF_INET && family != PF_INET6)
4050                 return 0;
4051
4052         /* Handle mapped IPv4 packets arriving via IPv6 sockets */
4053         if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
4054                 family = PF_INET;
4055
4056         /* If any sort of compatibility mode is enabled then handoff processing
4057          * to the selinux_sock_rcv_skb_compat() function to deal with the
4058          * special handling.  We do this in an attempt to keep this function
4059          * as fast and as clean as possible. */
4060         if (!selinux_policycap_netpeer)
4061                 return selinux_sock_rcv_skb_compat(sk, skb, family);
4062
4063         secmark_active = selinux_secmark_enabled();
4064         peerlbl_active = netlbl_enabled() || selinux_xfrm_enabled();
4065         if (!secmark_active && !peerlbl_active)
4066                 return 0;
4067
4068         COMMON_AUDIT_DATA_INIT(&ad, NET);
4069         ad.u.net.netif = skb->skb_iif;
4070         ad.u.net.family = family;
4071         err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL);
4072         if (err)
4073                 return err;
4074
4075         if (peerlbl_active) {
4076                 u32 peer_sid;
4077
4078                 err = selinux_skb_peerlbl_sid(skb, family, &peer_sid);
4079                 if (err)
4080                         return err;
4081                 err = selinux_inet_sys_rcv_skb(skb->skb_iif, addrp, family,
4082                                                peer_sid, &ad);
4083                 if (err) {
4084                         selinux_netlbl_err(skb, err, 0);
4085                         return err;
4086                 }
4087                 err = avc_has_perm(sk_sid, peer_sid, SECCLASS_PEER,
4088                                    PEER__RECV, &ad);
4089                 if (err)
4090                         selinux_netlbl_err(skb, err, 0);
4091         }
4092
4093         if (secmark_active) {
4094                 err = avc_has_perm(sk_sid, skb->secmark, SECCLASS_PACKET,
4095                                    PACKET__RECV, &ad);
4096                 if (err)
4097                         return err;
4098         }
4099
4100         return err;
4101 }
4102
4103 static int selinux_socket_getpeersec_stream(struct socket *sock, char __user *optval,
4104                                             int __user *optlen, unsigned len)
4105 {
4106         int err = 0;
4107         char *scontext;
4108         u32 scontext_len;
4109         struct sk_security_struct *sksec = sock->sk->sk_security;
4110         u32 peer_sid = SECSID_NULL;
4111
4112         if (sksec->sclass == SECCLASS_UNIX_STREAM_SOCKET ||
4113             sksec->sclass == SECCLASS_TCP_SOCKET)
4114                 peer_sid = sksec->peer_sid;
4115         if (peer_sid == SECSID_NULL)
4116                 return -ENOPROTOOPT;
4117
4118         err = security_sid_to_context(peer_sid, &scontext, &scontext_len);
4119         if (err)
4120                 return err;
4121
4122         if (scontext_len > len) {
4123                 err = -ERANGE;
4124                 goto out_len;
4125         }
4126
4127         if (copy_to_user(optval, scontext, scontext_len))
4128                 err = -EFAULT;
4129
4130 out_len:
4131         if (put_user(scontext_len, optlen))
4132                 err = -EFAULT;
4133         kfree(scontext);
4134         return err;
4135 }
4136
4137 static int selinux_socket_getpeersec_dgram(struct socket *sock, struct sk_buff *skb, u32 *secid)
4138 {
4139         u32 peer_secid = SECSID_NULL;
4140         u16 family;
4141
4142         if (skb && skb->protocol == htons(ETH_P_IP))
4143                 family = PF_INET;
4144         else if (skb && skb->protocol == htons(ETH_P_IPV6))
4145                 family = PF_INET6;
4146         else if (sock)
4147                 family = sock->sk->sk_family;
4148         else
4149                 goto out;
4150
4151         if (sock && family == PF_UNIX)
4152                 selinux_inode_getsecid(SOCK_INODE(sock), &peer_secid);
4153         else if (skb)
4154                 selinux_skb_peerlbl_sid(skb, family, &peer_secid);
4155
4156 out:
4157         *secid = peer_secid;
4158         if (peer_secid == SECSID_NULL)
4159                 return -EINVAL;
4160         return 0;
4161 }
4162
4163 static int selinux_sk_alloc_security(struct sock *sk, int family, gfp_t priority)
4164 {
4165         struct sk_security_struct *sksec;
4166
4167         sksec = kzalloc(sizeof(*sksec), priority);
4168         if (!sksec)
4169                 return -ENOMEM;
4170
4171         sksec->peer_sid = SECINITSID_UNLABELED;
4172         sksec->sid = SECINITSID_UNLABELED;
4173         selinux_netlbl_sk_security_reset(sksec);
4174         sk->sk_security = sksec;
4175
4176         return 0;
4177 }
4178
4179 static void selinux_sk_free_security(struct sock *sk)
4180 {
4181         struct sk_security_struct *sksec = sk->sk_security;
4182
4183         sk->sk_security = NULL;
4184         selinux_netlbl_sk_security_free(sksec);
4185         kfree(sksec);
4186 }
4187
4188 static void selinux_sk_clone_security(const struct sock *sk, struct sock *newsk)
4189 {
4190         struct sk_security_struct *sksec = sk->sk_security;
4191         struct sk_security_struct *newsksec = newsk->sk_security;
4192
4193         newsksec->sid = sksec->sid;
4194         newsksec->peer_sid = sksec->peer_sid;
4195         newsksec->sclass = sksec->sclass;
4196
4197         selinux_netlbl_sk_security_reset(newsksec);
4198 }
4199
4200 static void selinux_sk_getsecid(struct sock *sk, u32 *secid)
4201 {
4202         if (!sk)
4203                 *secid = SECINITSID_ANY_SOCKET;
4204         else {
4205                 struct sk_security_struct *sksec = sk->sk_security;
4206
4207                 *secid = sksec->sid;
4208         }
4209 }
4210
4211 static void selinux_sock_graft(struct sock *sk, struct socket *parent)
4212 {
4213         struct inode_security_struct *isec = SOCK_INODE(parent)->i_security;
4214         struct sk_security_struct *sksec = sk->sk_security;
4215
4216         if (sk->sk_family == PF_INET || sk->sk_family == PF_INET6 ||
4217             sk->sk_family == PF_UNIX)
4218                 isec->sid = sksec->sid;
4219         sksec->sclass = isec->sclass;
4220 }
4221
4222 static int selinux_inet_conn_request(struct sock *sk, struct sk_buff *skb,
4223                                      struct request_sock *req)
4224 {
4225         struct sk_security_struct *sksec = sk->sk_security;
4226         int err;
4227         u16 family = sk->sk_family;
4228         u32 newsid;
4229         u32 peersid;
4230
4231         /* handle mapped IPv4 packets arriving via IPv6 sockets */
4232         if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
4233                 family = PF_INET;
4234
4235         err = selinux_skb_peerlbl_sid(skb, family, &peersid);
4236         if (err)
4237                 return err;
4238         if (peersid == SECSID_NULL) {
4239                 req->secid = sksec->sid;
4240                 req->peer_secid = SECSID_NULL;
4241         } else {
4242                 err = security_sid_mls_copy(sksec->sid, peersid, &newsid);
4243                 if (err)
4244                         return err;
4245                 req->secid = newsid;
4246                 req->peer_secid = peersid;
4247         }
4248
4249         return selinux_netlbl_inet_conn_request(req, family);
4250 }
4251
4252 static void selinux_inet_csk_clone(struct sock *newsk,
4253                                    const struct request_sock *req)
4254 {
4255         struct sk_security_struct *newsksec = newsk->sk_security;
4256
4257         newsksec->sid = req->secid;
4258         newsksec->peer_sid = req->peer_secid;
4259         /* NOTE: Ideally, we should also get the isec->sid for the
4260            new socket in sync, but we don't have the isec available yet.
4261            So we will wait until sock_graft to do it, by which
4262            time it will have been created and available. */
4263
4264         /* We don't need to take any sort of lock here as we are the only
4265          * thread with access to newsksec */
4266         selinux_netlbl_inet_csk_clone(newsk, req->rsk_ops->family);
4267 }
4268
4269 static void selinux_inet_conn_established(struct sock *sk, struct sk_buff *skb)
4270 {
4271         u16 family = sk->sk_family;
4272         struct sk_security_struct *sksec = sk->sk_security;
4273
4274         /* handle mapped IPv4 packets arriving via IPv6 sockets */
4275         if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
4276                 family = PF_INET;
4277
4278         selinux_skb_peerlbl_sid(skb, family, &sksec->peer_sid);
4279 }
4280
4281 static int selinux_secmark_relabel_packet(u32 sid)
4282 {
4283         const struct task_security_struct *__tsec;
4284         u32 tsid;
4285
4286         __tsec = current_security();
4287         tsid = __tsec->sid;
4288
4289         return avc_has_perm(tsid, sid, SECCLASS_PACKET, PACKET__RELABELTO, NULL);
4290 }
4291
4292 static void selinux_secmark_refcount_inc(void)
4293 {
4294         atomic_inc(&selinux_secmark_refcount);
4295 }
4296
4297 static void selinux_secmark_refcount_dec(void)
4298 {
4299         atomic_dec(&selinux_secmark_refcount);
4300 }
4301
4302 static void selinux_req_classify_flow(const struct request_sock *req,
4303                                       struct flowi *fl)
4304 {
4305         fl->secid = req->secid;
4306 }
4307
4308 static int selinux_tun_dev_create(void)
4309 {
4310         u32 sid = current_sid();
4311
4312         /* we aren't taking into account the "sockcreate" SID since the socket
4313          * that is being created here is not a socket in the traditional sense,
4314          * instead it is a private sock, accessible only to the kernel, and
4315          * representing a wide range of network traffic spanning multiple
4316          * connections unlike traditional sockets - check the TUN driver to
4317          * get a better understanding of why this socket is special */
4318
4319         return avc_has_perm(sid, sid, SECCLASS_TUN_SOCKET, TUN_SOCKET__CREATE,
4320                             NULL);
4321 }
4322
4323 static void selinux_tun_dev_post_create(struct sock *sk)
4324 {
4325         struct sk_security_struct *sksec = sk->sk_security;
4326
4327         /* we don't currently perform any NetLabel based labeling here and it
4328          * isn't clear that we would want to do so anyway; while we could apply
4329          * labeling without the support of the TUN user the resulting labeled
4330          * traffic from the other end of the connection would almost certainly
4331          * cause confusion to the TUN user that had no idea network labeling
4332          * protocols were being used */
4333
4334         /* see the comments in selinux_tun_dev_create() about why we don't use
4335          * the sockcreate SID here */
4336
4337         sksec->sid = current_sid();
4338         sksec->sclass = SECCLASS_TUN_SOCKET;
4339 }
4340
4341 static int selinux_tun_dev_attach(struct sock *sk)
4342 {
4343         struct sk_security_struct *sksec = sk->sk_security;
4344         u32 sid = current_sid();
4345         int err;
4346
4347         err = avc_has_perm(sid, sksec->sid, SECCLASS_TUN_SOCKET,
4348                            TUN_SOCKET__RELABELFROM, NULL);
4349         if (err)
4350                 return err;
4351         err = avc_has_perm(sid, sid, SECCLASS_TUN_SOCKET,
4352                            TUN_SOCKET__RELABELTO, NULL);
4353         if (err)
4354                 return err;
4355
4356         sksec->sid = sid;
4357
4358         return 0;
4359 }
4360
4361 static int selinux_nlmsg_perm(struct sock *sk, struct sk_buff *skb)
4362 {
4363         int err = 0;
4364         u32 perm;
4365         struct nlmsghdr *nlh;
4366         struct sk_security_struct *sksec = sk->sk_security;
4367
4368         if (skb->len < NLMSG_SPACE(0)) {
4369                 err = -EINVAL;
4370                 goto out;
4371         }
4372         nlh = nlmsg_hdr(skb);
4373
4374         err = selinux_nlmsg_lookup(sksec->sclass, nlh->nlmsg_type, &perm);
4375         if (err) {
4376                 if (err == -EINVAL) {
4377                         audit_log(current->audit_context, GFP_KERNEL, AUDIT_SELINUX_ERR,
4378                                   "SELinux:  unrecognized netlink message"
4379                                   " type=%hu for sclass=%hu\n",
4380                                   nlh->nlmsg_type, sksec->sclass);
4381                         if (!selinux_enforcing || security_get_allow_unknown())
4382                                 err = 0;
4383                 }
4384
4385                 /* Ignore */
4386                 if (err == -ENOENT)
4387                         err = 0;
4388                 goto out;
4389         }
4390
4391         err = sock_has_perm(current, sk, perm);
4392 out:
4393         return err;
4394 }
4395
4396 #ifdef CONFIG_NETFILTER
4397
4398 static unsigned int selinux_ip_forward(struct sk_buff *skb, int ifindex,
4399                                        u16 family)
4400 {
4401         int err;
4402         char *addrp;
4403         u32 peer_sid;
4404         struct common_audit_data ad;
4405         u8 secmark_active;
4406         u8 netlbl_active;
4407         u8 peerlbl_active;
4408
4409         if (!selinux_policycap_netpeer)
4410                 return NF_ACCEPT;
4411
4412         secmark_active = selinux_secmark_enabled();
4413         netlbl_active = netlbl_enabled();
4414         peerlbl_active = netlbl_active || selinux_xfrm_enabled();
4415         if (!secmark_active && !peerlbl_active)
4416                 return NF_ACCEPT;
4417
4418         if (selinux_skb_peerlbl_sid(skb, family, &peer_sid) != 0)
4419                 return NF_DROP;
4420
4421         COMMON_AUDIT_DATA_INIT(&ad, NET);
4422         ad.u.net.netif = ifindex;
4423         ad.u.net.family = family;
4424         if (selinux_parse_skb(skb, &ad, &addrp, 1, NULL) != 0)
4425                 return NF_DROP;
4426
4427         if (peerlbl_active) {
4428                 err = selinux_inet_sys_rcv_skb(ifindex, addrp, family,
4429                                                peer_sid, &ad);
4430                 if (err) {
4431                         selinux_netlbl_err(skb, err, 1);
4432                         return NF_DROP;
4433                 }
4434         }
4435
4436         if (secmark_active)
4437                 if (avc_has_perm(peer_sid, skb->secmark,
4438                                  SECCLASS_PACKET, PACKET__FORWARD_IN, &ad))
4439                         return NF_DROP;
4440
4441         if (netlbl_active)
4442                 /* we do this in the FORWARD path and not the POST_ROUTING
4443                  * path because we want to make sure we apply the necessary
4444                  * labeling before IPsec is applied so we can leverage AH
4445                  * protection */
4446                 if (selinux_netlbl_skbuff_setsid(skb, family, peer_sid) != 0)
4447                         return NF_DROP;
4448
4449         return NF_ACCEPT;
4450 }
4451
4452 static unsigned int selinux_ipv4_forward(unsigned int hooknum,
4453                                          struct sk_buff *skb,
4454                                          const struct net_device *in,
4455                                          const struct net_device *out,
4456                                          int (*okfn)(struct sk_buff *))
4457 {
4458         return selinux_ip_forward(skb, in->ifindex, PF_INET);
4459 }
4460
4461 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
4462 static unsigned int selinux_ipv6_forward(unsigned int hooknum,
4463                                          struct sk_buff *skb,
4464                                          const struct net_device *in,
4465                                          const struct net_device *out,
4466                                          int (*okfn)(struct sk_buff *))
4467 {
4468         return selinux_ip_forward(skb, in->ifindex, PF_INET6);
4469 }
4470 #endif  /* IPV6 */
4471
4472 static unsigned int selinux_ip_output(struct sk_buff *skb,
4473                                       u16 family)
4474 {
4475         u32 sid;
4476
4477         if (!netlbl_enabled())
4478                 return NF_ACCEPT;
4479
4480         /* we do this in the LOCAL_OUT path and not the POST_ROUTING path
4481          * because we want to make sure we apply the necessary labeling
4482          * before IPsec is applied so we can leverage AH protection */
4483         if (skb->sk) {
4484                 struct sk_security_struct *sksec = skb->sk->sk_security;
4485                 sid = sksec->sid;
4486         } else
4487                 sid = SECINITSID_KERNEL;
4488         if (selinux_netlbl_skbuff_setsid(skb, family, sid) != 0)
4489                 return NF_DROP;
4490
4491         return NF_ACCEPT;
4492 }
4493
4494 static unsigned int selinux_ipv4_output(unsigned int hooknum,
4495                                         struct sk_buff *skb,
4496                                         const struct net_device *in,
4497                                         const struct net_device *out,
4498                                         int (*okfn)(struct sk_buff *))
4499 {
4500         return selinux_ip_output(skb, PF_INET);
4501 }
4502
4503 static unsigned int selinux_ip_postroute_compat(struct sk_buff *skb,
4504                                                 int ifindex,
4505                                                 u16 family)
4506 {
4507         struct sock *sk = skb->sk;
4508         struct sk_security_struct *sksec;
4509         struct common_audit_data ad;
4510         char *addrp;
4511         u8 proto;
4512
4513         if (sk == NULL)
4514                 return NF_ACCEPT;
4515         sksec = sk->sk_security;
4516
4517         COMMON_AUDIT_DATA_INIT(&ad, NET);
4518         ad.u.net.netif = ifindex;
4519         ad.u.net.family = family;
4520         if (selinux_parse_skb(skb, &ad, &addrp, 0, &proto))
4521                 return NF_DROP;
4522
4523         if (selinux_secmark_enabled())
4524                 if (avc_has_perm(sksec->sid, skb->secmark,
4525                                  SECCLASS_PACKET, PACKET__SEND, &ad))
4526                         return NF_DROP_ERR(-ECONNREFUSED);
4527
4528         if (selinux_policycap_netpeer)
4529                 if (selinux_xfrm_postroute_last(sksec->sid, skb, &ad, proto))
4530                         return NF_DROP_ERR(-ECONNREFUSED);
4531
4532         return NF_ACCEPT;
4533 }
4534
4535 static unsigned int selinux_ip_postroute(struct sk_buff *skb, int ifindex,
4536                                          u16 family)
4537 {
4538         u32 secmark_perm;
4539         u32 peer_sid;
4540         struct sock *sk;
4541         struct common_audit_data ad;
4542         char *addrp;
4543         u8 secmark_active;
4544         u8 peerlbl_active;
4545
4546         /* If any sort of compatibility mode is enabled then handoff processing
4547          * to the selinux_ip_postroute_compat() function to deal with the
4548          * special handling.  We do this in an attempt to keep this function
4549          * as fast and as clean as possible. */
4550         if (!selinux_policycap_netpeer)
4551                 return selinux_ip_postroute_compat(skb, ifindex, family);
4552 #ifdef CONFIG_XFRM
4553         /* If skb->dst->xfrm is non-NULL then the packet is undergoing an IPsec
4554          * packet transformation so allow the packet to pass without any checks
4555          * since we'll have another chance to perform access control checks
4556          * when the packet is on it's final way out.
4557          * NOTE: there appear to be some IPv6 multicast cases where skb->dst
4558          *       is NULL, in this case go ahead and apply access control. */
4559         if (skb_dst(skb) != NULL && skb_dst(skb)->xfrm != NULL)
4560                 return NF_ACCEPT;
4561 #endif
4562         secmark_active = selinux_secmark_enabled();
4563         peerlbl_active = netlbl_enabled() || selinux_xfrm_enabled();
4564         if (!secmark_active && !peerlbl_active)
4565                 return NF_ACCEPT;
4566
4567         /* if the packet is being forwarded then get the peer label from the
4568          * packet itself; otherwise check to see if it is from a local
4569          * application or the kernel, if from an application get the peer label
4570          * from the sending socket, otherwise use the kernel's sid */
4571         sk = skb->sk;
4572         if (sk == NULL) {
4573                 switch (family) {
4574                 case PF_INET:
4575                         if (IPCB(skb)->flags & IPSKB_FORWARDED)
4576                                 secmark_perm = PACKET__FORWARD_OUT;
4577                         else
4578                                 secmark_perm = PACKET__SEND;
4579                         break;
4580                 case PF_INET6:
4581                         if (IP6CB(skb)->flags & IP6SKB_FORWARDED)
4582                                 secmark_perm = PACKET__FORWARD_OUT;
4583                         else
4584                                 secmark_perm = PACKET__SEND;
4585                         break;
4586                 default:
4587                         return NF_DROP_ERR(-ECONNREFUSED);
4588                 }
4589                 if (secmark_perm == PACKET__FORWARD_OUT) {
4590                         if (selinux_skb_peerlbl_sid(skb, family, &peer_sid))
4591                                 return NF_DROP;
4592                 } else
4593                         peer_sid = SECINITSID_KERNEL;
4594         } else {
4595                 struct sk_security_struct *sksec = sk->sk_security;
4596                 peer_sid = sksec->sid;
4597                 secmark_perm = PACKET__SEND;
4598         }
4599
4600         COMMON_AUDIT_DATA_INIT(&ad, NET);
4601         ad.u.net.netif = ifindex;
4602         ad.u.net.family = family;
4603         if (selinux_parse_skb(skb, &ad, &addrp, 0, NULL))
4604                 return NF_DROP;
4605
4606         if (secmark_active)
4607                 if (avc_has_perm(peer_sid, skb->secmark,
4608                                  SECCLASS_PACKET, secmark_perm, &ad))
4609                         return NF_DROP_ERR(-ECONNREFUSED);
4610
4611         if (peerlbl_active) {
4612                 u32 if_sid;
4613                 u32 node_sid;
4614
4615                 if (sel_netif_sid(ifindex, &if_sid))
4616                         return NF_DROP;
4617                 if (avc_has_perm(peer_sid, if_sid,
4618                                  SECCLASS_NETIF, NETIF__EGRESS, &ad))
4619                         return NF_DROP_ERR(-ECONNREFUSED);
4620
4621                 if (sel_netnode_sid(addrp, family, &node_sid))
4622                         return NF_DROP;
4623                 if (avc_has_perm(peer_sid, node_sid,
4624                                  SECCLASS_NODE, NODE__SENDTO, &ad))
4625                         return NF_DROP_ERR(-ECONNREFUSED);
4626         }
4627
4628         return NF_ACCEPT;
4629 }
4630
4631 static unsigned int selinux_ipv4_postroute(unsigned int hooknum,
4632                                            struct sk_buff *skb,
4633                                            const struct net_device *in,
4634                                            const struct net_device *out,
4635                                            int (*okfn)(struct sk_buff *))
4636 {
4637         return selinux_ip_postroute(skb, out->ifindex, PF_INET);
4638 }
4639
4640 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
4641 static unsigned int selinux_ipv6_postroute(unsigned int hooknum,
4642                                            struct sk_buff *skb,
4643                                            const struct net_device *in,
4644                                            const struct net_device *out,
4645                                            int (*okfn)(struct sk_buff *))
4646 {
4647         return selinux_ip_postroute(skb, out->ifindex, PF_INET6);
4648 }
4649 #endif  /* IPV6 */
4650
4651 #endif  /* CONFIG_NETFILTER */
4652
4653 static int selinux_netlink_send(struct sock *sk, struct sk_buff *skb)
4654 {
4655         int err;
4656
4657         err = cap_netlink_send(sk, skb);
4658         if (err)
4659                 return err;
4660
4661         return selinux_nlmsg_perm(sk, skb);
4662 }
4663
4664 static int selinux_netlink_recv(struct sk_buff *skb, int capability)
4665 {
4666         int err;
4667         struct common_audit_data ad;
4668
4669         err = cap_netlink_recv(skb, capability);
4670         if (err)
4671                 return err;
4672
4673         COMMON_AUDIT_DATA_INIT(&ad, CAP);
4674         ad.u.cap = capability;
4675
4676         return avc_has_perm(NETLINK_CB(skb).sid, NETLINK_CB(skb).sid,
4677                             SECCLASS_CAPABILITY, CAP_TO_MASK(capability), &ad);
4678 }
4679
4680 static int ipc_alloc_security(struct task_struct *task,
4681                               struct kern_ipc_perm *perm,
4682                               u16 sclass)
4683 {
4684         struct ipc_security_struct *isec;
4685         u32 sid;
4686
4687         isec = kzalloc(sizeof(struct ipc_security_struct), GFP_KERNEL);
4688         if (!isec)
4689                 return -ENOMEM;
4690
4691         sid = task_sid(task);
4692         isec->sclass = sclass;
4693         isec->sid = sid;
4694         perm->security = isec;
4695
4696         return 0;
4697 }
4698
4699 static void ipc_free_security(struct kern_ipc_perm *perm)
4700 {
4701         struct ipc_security_struct *isec = perm->security;
4702         perm->security = NULL;
4703         kfree(isec);
4704 }
4705
4706 static int msg_msg_alloc_security(struct msg_msg *msg)
4707 {
4708         struct msg_security_struct *msec;
4709
4710         msec = kzalloc(sizeof(struct msg_security_struct), GFP_KERNEL);
4711         if (!msec)
4712                 return -ENOMEM;
4713
4714         msec->sid = SECINITSID_UNLABELED;
4715         msg->security = msec;
4716
4717         return 0;
4718 }
4719
4720 static void msg_msg_free_security(struct msg_msg *msg)
4721 {
4722         struct msg_security_struct *msec = msg->security;
4723
4724         msg->security = NULL;
4725         kfree(msec);
4726 }
4727
4728 static int ipc_has_perm(struct kern_ipc_perm *ipc_perms,
4729                         u32 perms)
4730 {
4731         struct ipc_security_struct *isec;
4732         struct common_audit_data ad;
4733         u32 sid = current_sid();
4734
4735         isec = ipc_perms->security;
4736
4737         COMMON_AUDIT_DATA_INIT(&ad, IPC);
4738         ad.u.ipc_id = ipc_perms->key;
4739
4740         return avc_has_perm(sid, isec->sid, isec->sclass, perms, &ad);
4741 }
4742
4743 static int selinux_msg_msg_alloc_security(struct msg_msg *msg)
4744 {
4745         return msg_msg_alloc_security(msg);
4746 }
4747
4748 static void selinux_msg_msg_free_security(struct msg_msg *msg)
4749 {
4750         msg_msg_free_security(msg);
4751 }
4752
4753 /* message queue security operations */
4754 static int selinux_msg_queue_alloc_security(struct msg_queue *msq)
4755 {
4756         struct ipc_security_struct *isec;
4757         struct common_audit_data ad;
4758         u32 sid = current_sid();
4759         int rc;
4760
4761         rc = ipc_alloc_security(current, &msq->q_perm, SECCLASS_MSGQ);
4762         if (rc)
4763                 return rc;
4764
4765         isec = msq->q_perm.security;
4766
4767         COMMON_AUDIT_DATA_INIT(&ad, IPC);
4768         ad.u.ipc_id = msq->q_perm.key;
4769
4770         rc = avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
4771                           MSGQ__CREATE, &ad);
4772         if (rc) {
4773                 ipc_free_security(&msq->q_perm);
4774                 return rc;
4775         }
4776         return 0;
4777 }
4778
4779 static void selinux_msg_queue_free_security(struct msg_queue *msq)
4780 {
4781         ipc_free_security(&msq->q_perm);
4782 }
4783
4784 static int selinux_msg_queue_associate(struct msg_queue *msq, int msqflg)
4785 {
4786         struct ipc_security_struct *isec;
4787         struct common_audit_data ad;
4788         u32 sid = current_sid();
4789
4790         isec = msq->q_perm.security;
4791
4792         COMMON_AUDIT_DATA_INIT(&ad, IPC);
4793         ad.u.ipc_id = msq->q_perm.key;
4794
4795         return avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
4796                             MSGQ__ASSOCIATE, &ad);
4797 }
4798
4799 static int selinux_msg_queue_msgctl(struct msg_queue *msq, int cmd)
4800 {
4801         int err;
4802         int perms;
4803
4804         switch (cmd) {
4805         case IPC_INFO:
4806         case MSG_INFO:
4807                 /* No specific object, just general system-wide information. */
4808                 return task_has_system(current, SYSTEM__IPC_INFO);
4809         case IPC_STAT:
4810         case MSG_STAT:
4811                 perms = MSGQ__GETATTR | MSGQ__ASSOCIATE;
4812                 break;
4813         case IPC_SET:
4814                 perms = MSGQ__SETATTR;
4815                 break;
4816         case IPC_RMID:
4817                 perms = MSGQ__DESTROY;
4818                 break;
4819         default:
4820                 return 0;
4821         }
4822
4823         err = ipc_has_perm(&msq->q_perm, perms);
4824         return err;
4825 }
4826
4827 static int selinux_msg_queue_msgsnd(struct msg_queue *msq, struct msg_msg *msg, int msqflg)
4828 {
4829         struct ipc_security_struct *isec;
4830         struct msg_security_struct *msec;
4831         struct common_audit_data ad;
4832         u32 sid = current_sid();
4833         int rc;
4834
4835         isec = msq->q_perm.security;
4836         msec = msg->security;
4837
4838         /*
4839          * First time through, need to assign label to the message
4840          */
4841         if (msec->sid == SECINITSID_UNLABELED) {
4842                 /*
4843                  * Compute new sid based on current process and
4844                  * message queue this message will be stored in
4845                  */
4846                 rc = security_transition_sid(sid, isec->sid, SECCLASS_MSG,
4847                                              &msec->sid);
4848                 if (rc)
4849                         return rc;
4850         }
4851
4852         COMMON_AUDIT_DATA_INIT(&ad, IPC);
4853         ad.u.ipc_id = msq->q_perm.key;
4854
4855         /* Can this process write to the queue? */
4856         rc = avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
4857                           MSGQ__WRITE, &ad);
4858         if (!rc)
4859                 /* Can this process send the message */
4860                 rc = avc_has_perm(sid, msec->sid, SECCLASS_MSG,
4861                                   MSG__SEND, &ad);
4862         if (!rc)
4863                 /* Can the message be put in the queue? */
4864                 rc = avc_has_perm(msec->sid, isec->sid, SECCLASS_MSGQ,
4865                                   MSGQ__ENQUEUE, &ad);
4866
4867         return rc;
4868 }
4869
4870 static int selinux_msg_queue_msgrcv(struct msg_queue *msq, struct msg_msg *msg,
4871                                     struct task_struct *target,
4872                                     long type, int mode)
4873 {
4874         struct ipc_security_struct *isec;
4875         struct msg_security_struct *msec;
4876         struct common_audit_data ad;
4877         u32 sid = task_sid(target);
4878         int rc;
4879
4880         isec = msq->q_perm.security;
4881         msec = msg->security;
4882
4883         COMMON_AUDIT_DATA_INIT(&ad, IPC);
4884         ad.u.ipc_id = msq->q_perm.key;
4885
4886         rc = avc_has_perm(sid, isec->sid,
4887                           SECCLASS_MSGQ, MSGQ__READ, &ad);
4888         if (!rc)
4889                 rc = avc_has_perm(sid, msec->sid,
4890                                   SECCLASS_MSG, MSG__RECEIVE, &ad);
4891         return rc;
4892 }
4893
4894 /* Shared Memory security operations */
4895 static int selinux_shm_alloc_security(struct shmid_kernel *shp)
4896 {
4897         struct ipc_security_struct *isec;
4898         struct common_audit_data ad;
4899         u32 sid = current_sid();
4900         int rc;
4901
4902         rc = ipc_alloc_security(current, &shp->shm_perm, SECCLASS_SHM);
4903         if (rc)
4904                 return rc;
4905
4906         isec = shp->shm_perm.security;
4907
4908         COMMON_AUDIT_DATA_INIT(&ad, IPC);
4909         ad.u.ipc_id = shp->shm_perm.key;
4910
4911         rc = avc_has_perm(sid, isec->sid, SECCLASS_SHM,
4912                           SHM__CREATE, &ad);
4913         if (rc) {
4914                 ipc_free_security(&shp->shm_perm);
4915                 return rc;
4916         }
4917         return 0;
4918 }
4919
4920 static void selinux_shm_free_security(struct shmid_kernel *shp)
4921 {
4922         ipc_free_security(&shp->shm_perm);
4923 }
4924
4925 static int selinux_shm_associate(struct shmid_kernel *shp, int shmflg)
4926 {
4927         struct ipc_security_struct *isec;
4928         struct common_audit_data ad;
4929         u32 sid = current_sid();
4930
4931         isec = shp->shm_perm.security;
4932
4933         COMMON_AUDIT_DATA_INIT(&ad, IPC);
4934         ad.u.ipc_id = shp->shm_perm.key;
4935
4936         return avc_has_perm(sid, isec->sid, SECCLASS_SHM,
4937                             SHM__ASSOCIATE, &ad);
4938 }
4939
4940 /* Note, at this point, shp is locked down */
4941 static int selinux_shm_shmctl(struct shmid_kernel *shp, int cmd)
4942 {
4943         int perms;
4944         int err;
4945
4946         switch (cmd) {
4947         case IPC_INFO:
4948         case SHM_INFO:
4949                 /* No specific object, just general system-wide information. */
4950                 return task_has_system(current, SYSTEM__IPC_INFO);
4951         case IPC_STAT:
4952         case SHM_STAT:
4953                 perms = SHM__GETATTR | SHM__ASSOCIATE;
4954                 break;
4955         case IPC_SET:
4956                 perms = SHM__SETATTR;
4957                 break;
4958         case SHM_LOCK:
4959         case SHM_UNLOCK:
4960                 perms = SHM__LOCK;
4961                 break;
4962         case IPC_RMID:
4963                 perms = SHM__DESTROY;
4964                 break;
4965         default:
4966                 return 0;
4967         }
4968
4969         err = ipc_has_perm(&shp->shm_perm, perms);
4970         return err;
4971 }
4972
4973 static int selinux_shm_shmat(struct shmid_kernel *shp,
4974                              char __user *shmaddr, int shmflg)
4975 {
4976         u32 perms;
4977
4978         if (shmflg & SHM_RDONLY)
4979                 perms = SHM__READ;
4980         else
4981                 perms = SHM__READ | SHM__WRITE;
4982
4983         return ipc_has_perm(&shp->shm_perm, perms);
4984 }
4985
4986 /* Semaphore security operations */
4987 static int selinux_sem_alloc_security(struct sem_array *sma)
4988 {
4989         struct ipc_security_struct *isec;
4990         struct common_audit_data ad;
4991         u32 sid = current_sid();
4992         int rc;
4993
4994         rc = ipc_alloc_security(current, &sma->sem_perm, SECCLASS_SEM);
4995         if (rc)
4996                 return rc;
4997
4998         isec = sma->sem_perm.security;
4999
5000         COMMON_AUDIT_DATA_INIT(&ad, IPC);
5001         ad.u.ipc_id = sma->sem_perm.key;
5002
5003         rc = avc_has_perm(sid, isec->sid, SECCLASS_SEM,
5004                           SEM__CREATE, &ad);
5005         if (rc) {
5006                 ipc_free_security(&sma->sem_perm);
5007                 return rc;
5008         }
5009         return 0;
5010 }
5011
5012 static void selinux_sem_free_security(struct sem_array *sma)
5013 {
5014         ipc_free_security(&sma->sem_perm);
5015 }
5016
5017 static int selinux_sem_associate(struct sem_array *sma, int semflg)
5018 {
5019         struct ipc_security_struct *isec;
5020         struct common_audit_data ad;
5021         u32 sid = current_sid();
5022
5023         isec = sma->sem_perm.security;
5024
5025         COMMON_AUDIT_DATA_INIT(&ad, IPC);
5026         ad.u.ipc_id = sma->sem_perm.key;
5027
5028         return avc_has_perm(sid, isec->sid, SECCLASS_SEM,
5029                             SEM__ASSOCIATE, &ad);
5030 }
5031
5032 /* Note, at this point, sma is locked down */
5033 static int selinux_sem_semctl(struct sem_array *sma, int cmd)
5034 {
5035         int err;
5036         u32 perms;
5037
5038         switch (cmd) {
5039         case IPC_INFO:
5040         case SEM_INFO:
5041                 /* No specific object, just general system-wide information. */
5042                 return task_has_system(current, SYSTEM__IPC_INFO);
5043         case GETPID:
5044         case GETNCNT:
5045         case GETZCNT:
5046                 perms = SEM__GETATTR;
5047                 break;
5048         case GETVAL:
5049         case GETALL:
5050                 perms = SEM__READ;
5051                 break;
5052         case SETVAL:
5053         case SETALL:
5054                 perms = SEM__WRITE;
5055                 break;
5056         case IPC_RMID:
5057                 perms = SEM__DESTROY;
5058                 break;
5059         case IPC_SET:
5060                 perms = SEM__SETATTR;
5061                 break;
5062         case IPC_STAT:
5063         case SEM_STAT:
5064                 perms = SEM__GETATTR | SEM__ASSOCIATE;
5065                 break;
5066         default:
5067                 return 0;
5068         }
5069
5070         err = ipc_has_perm(&sma->sem_perm, perms);
5071         return err;
5072 }
5073
5074 static int selinux_sem_semop(struct sem_array *sma,
5075                              struct sembuf *sops, unsigned nsops, int alter)
5076 {
5077         u32 perms;
5078
5079         if (alter)
5080                 perms = SEM__READ | SEM__WRITE;
5081         else
5082                 perms = SEM__READ;
5083
5084         return ipc_has_perm(&sma->sem_perm, perms);
5085 }
5086
5087 static int selinux_ipc_permission(struct kern_ipc_perm *ipcp, short flag)
5088 {
5089         u32 av = 0;
5090
5091         av = 0;
5092         if (flag & S_IRUGO)
5093                 av |= IPC__UNIX_READ;
5094         if (flag & S_IWUGO)
5095                 av |= IPC__UNIX_WRITE;
5096
5097         if (av == 0)
5098                 return 0;
5099
5100         return ipc_has_perm(ipcp, av);
5101 }
5102
5103 static void selinux_ipc_getsecid(struct kern_ipc_perm *ipcp, u32 *secid)
5104 {
5105         struct ipc_security_struct *isec = ipcp->security;
5106         *secid = isec->sid;
5107 }
5108
5109 static void selinux_d_instantiate(struct dentry *dentry, struct inode *inode)
5110 {
5111         if (inode)
5112                 inode_doinit_with_dentry(inode, dentry);
5113 }
5114
5115 static int selinux_getprocattr(struct task_struct *p,
5116                                char *name, char **value)
5117 {
5118         const struct task_security_struct *__tsec;
5119         u32 sid;
5120         int error;
5121         unsigned len;
5122
5123         if (current != p) {
5124                 error = current_has_perm(p, PROCESS__GETATTR);
5125                 if (error)
5126                         return error;
5127         }
5128
5129         rcu_read_lock();
5130         __tsec = __task_cred(p)->security;
5131
5132         if (!strcmp(name, "current"))
5133                 sid = __tsec->sid;
5134         else if (!strcmp(name, "prev"))
5135                 sid = __tsec->osid;
5136         else if (!strcmp(name, "exec"))
5137                 sid = __tsec->exec_sid;
5138         else if (!strcmp(name, "fscreate"))
5139                 sid = __tsec->create_sid;
5140         else if (!strcmp(name, "keycreate"))
5141                 sid = __tsec->keycreate_sid;
5142         else if (!strcmp(name, "sockcreate"))
5143                 sid = __tsec->sockcreate_sid;
5144         else
5145                 goto invalid;
5146         rcu_read_unlock();
5147
5148         if (!sid)
5149                 return 0;
5150
5151         error = security_sid_to_context(sid, value, &len);
5152         if (error)
5153                 return error;
5154         return len;
5155
5156 invalid:
5157         rcu_read_unlock();
5158         return -EINVAL;
5159 }
5160
5161 static int selinux_setprocattr(struct task_struct *p,
5162                                char *name, void *value, size_t size)
5163 {
5164         struct task_security_struct *tsec;
5165         struct task_struct *tracer;
5166         struct cred *new;
5167         u32 sid = 0, ptsid;
5168         int error;
5169         char *str = value;
5170
5171         if (current != p) {
5172                 /* SELinux only allows a process to change its own
5173                    security attributes. */
5174                 return -EACCES;
5175         }
5176
5177         /*
5178          * Basic control over ability to set these attributes at all.
5179          * current == p, but we'll pass them separately in case the
5180          * above restriction is ever removed.
5181          */
5182         if (!strcmp(name, "exec"))
5183                 error = current_has_perm(p, PROCESS__SETEXEC);
5184         else if (!strcmp(name, "fscreate"))
5185                 error = current_has_perm(p, PROCESS__SETFSCREATE);
5186         else if (!strcmp(name, "keycreate"))
5187                 error = current_has_perm(p, PROCESS__SETKEYCREATE);
5188         else if (!strcmp(name, "sockcreate"))
5189                 error = current_has_perm(p, PROCESS__SETSOCKCREATE);
5190         else if (!strcmp(name, "current"))
5191                 error = current_has_perm(p, PROCESS__SETCURRENT);
5192         else
5193                 error = -EINVAL;
5194         if (error)
5195                 return error;
5196
5197         /* Obtain a SID for the context, if one was specified. */
5198         if (size && str[1] && str[1] != '\n') {
5199                 if (str[size-1] == '\n') {
5200                         str[size-1] = 0;
5201                         size--;
5202                 }
5203                 error = security_context_to_sid(value, size, &sid);
5204                 if (error == -EINVAL && !strcmp(name, "fscreate")) {
5205                         if (!capable(CAP_MAC_ADMIN))
5206                                 return error;
5207                         error = security_context_to_sid_force(value, size,
5208                                                               &sid);
5209                 }
5210                 if (error)
5211                         return error;
5212         }
5213
5214         new = prepare_creds();
5215         if (!new)
5216                 return -ENOMEM;
5217
5218         /* Permission checking based on the specified context is
5219            performed during the actual operation (execve,
5220            open/mkdir/...), when we know the full context of the
5221            operation.  See selinux_bprm_set_creds for the execve
5222            checks and may_create for the file creation checks. The
5223            operation will then fail if the context is not permitted. */
5224         tsec = new->security;
5225         if (!strcmp(name, "exec")) {
5226                 tsec->exec_sid = sid;
5227         } else if (!strcmp(name, "fscreate")) {
5228                 tsec->create_sid = sid;
5229         } else if (!strcmp(name, "keycreate")) {
5230                 error = may_create_key(sid, p);
5231                 if (error)
5232                         goto abort_change;
5233                 tsec->keycreate_sid = sid;
5234         } else if (!strcmp(name, "sockcreate")) {
5235                 tsec->sockcreate_sid = sid;
5236         } else if (!strcmp(name, "current")) {
5237                 error = -EINVAL;
5238                 if (sid == 0)
5239                         goto abort_change;
5240
5241                 /* Only allow single threaded processes to change context */
5242                 error = -EPERM;
5243                 if (!current_is_single_threaded()) {
5244                         error = security_bounded_transition(tsec->sid, sid);
5245                         if (error)
5246                                 goto abort_change;
5247                 }
5248
5249                 /* Check permissions for the transition. */
5250                 error = avc_has_perm(tsec->sid, sid, SECCLASS_PROCESS,
5251                                      PROCESS__DYNTRANSITION, NULL);
5252                 if (error)
5253                         goto abort_change;
5254
5255                 /* Check for ptracing, and update the task SID if ok.
5256                    Otherwise, leave SID unchanged and fail. */
5257                 ptsid = 0;
5258                 task_lock(p);
5259                 tracer = tracehook_tracer_task(p);
5260                 if (tracer)
5261                         ptsid = task_sid(tracer);
5262                 task_unlock(p);
5263
5264                 if (tracer) {
5265                         error = avc_has_perm(ptsid, sid, SECCLASS_PROCESS,
5266                                              PROCESS__PTRACE, NULL);
5267                         if (error)
5268                                 goto abort_change;
5269                 }
5270
5271                 tsec->sid = sid;
5272         } else {
5273                 error = -EINVAL;
5274                 goto abort_change;
5275         }
5276
5277         commit_creds(new);
5278         return size;
5279
5280 abort_change:
5281         abort_creds(new);
5282         return error;
5283 }
5284
5285 static int selinux_secid_to_secctx(u32 secid, char **secdata, u32 *seclen)
5286 {
5287         return security_sid_to_context(secid, secdata, seclen);
5288 }
5289
5290 static int selinux_secctx_to_secid(const char *secdata, u32 seclen, u32 *secid)
5291 {
5292         return security_context_to_sid(secdata, seclen, secid);
5293 }
5294
5295 static void selinux_release_secctx(char *secdata, u32 seclen)
5296 {
5297         kfree(secdata);
5298 }
5299
5300 /*
5301  *      called with inode->i_mutex locked
5302  */
5303 static int selinux_inode_notifysecctx(struct inode *inode, void *ctx, u32 ctxlen)
5304 {
5305         return selinux_inode_setsecurity(inode, XATTR_SELINUX_SUFFIX, ctx, ctxlen, 0);
5306 }
5307
5308 /*
5309  *      called with inode->i_mutex locked
5310  */
5311 static int selinux_inode_setsecctx(struct dentry *dentry, void *ctx, u32 ctxlen)
5312 {
5313         return __vfs_setxattr_noperm(dentry, XATTR_NAME_SELINUX, ctx, ctxlen, 0);
5314 }
5315
5316 static int selinux_inode_getsecctx(struct inode *inode, void **ctx, u32 *ctxlen)
5317 {
5318         int len = 0;
5319         len = selinux_inode_getsecurity(inode, XATTR_SELINUX_SUFFIX,
5320                                                 ctx, true);
5321         if (len < 0)
5322                 return len;
5323         *ctxlen = len;
5324         return 0;
5325 }
5326 #ifdef CONFIG_KEYS
5327
5328 static int selinux_key_alloc(struct key *k, const struct cred *cred,
5329                              unsigned long flags)
5330 {
5331         const struct task_security_struct *tsec;
5332         struct key_security_struct *ksec;
5333
5334         ksec = kzalloc(sizeof(struct key_security_struct), GFP_KERNEL);
5335         if (!ksec)
5336                 return -ENOMEM;
5337
5338         tsec = cred->security;
5339         if (tsec->keycreate_sid)
5340                 ksec->sid = tsec->keycreate_sid;
5341         else
5342                 ksec->sid = tsec->sid;
5343
5344         k->security = ksec;
5345         return 0;
5346 }
5347
5348 static void selinux_key_free(struct key *k)
5349 {
5350         struct key_security_struct *ksec = k->security;
5351
5352         k->security = NULL;
5353         kfree(ksec);
5354 }
5355
5356 static int selinux_key_permission(key_ref_t key_ref,
5357                                   const struct cred *cred,
5358                                   key_perm_t perm)
5359 {
5360         struct key *key;
5361         struct key_security_struct *ksec;
5362         u32 sid;
5363
5364         /* if no specific permissions are requested, we skip the
5365            permission check. No serious, additional covert channels
5366            appear to be created. */
5367         if (perm == 0)
5368                 return 0;
5369
5370         sid = cred_sid(cred);
5371
5372         key = key_ref_to_ptr(key_ref);
5373         ksec = key->security;
5374
5375         return avc_has_perm(sid, ksec->sid, SECCLASS_KEY, perm, NULL);
5376 }
5377
5378 static int selinux_key_getsecurity(struct key *key, char **_buffer)
5379 {
5380         struct key_security_struct *ksec = key->security;
5381         char *context = NULL;
5382         unsigned len;
5383         int rc;
5384
5385         rc = security_sid_to_context(ksec->sid, &context, &len);
5386         if (!rc)
5387                 rc = len;
5388         *_buffer = context;
5389         return rc;
5390 }
5391
5392 #endif
5393
5394 static struct security_operations selinux_ops = {
5395         .name =                         "selinux",
5396
5397         .ptrace_access_check =          selinux_ptrace_access_check,
5398         .ptrace_traceme =               selinux_ptrace_traceme,
5399         .capget =                       selinux_capget,
5400         .capset =                       selinux_capset,
5401         .sysctl =                       selinux_sysctl,
5402         .capable =                      selinux_capable,
5403         .quotactl =                     selinux_quotactl,
5404         .quota_on =                     selinux_quota_on,
5405         .syslog =                       selinux_syslog,
5406         .vm_enough_memory =             selinux_vm_enough_memory,
5407
5408         .netlink_send =                 selinux_netlink_send,
5409         .netlink_recv =                 selinux_netlink_recv,
5410
5411         .bprm_set_creds =               selinux_bprm_set_creds,
5412         .bprm_committing_creds =        selinux_bprm_committing_creds,
5413         .bprm_committed_creds =         selinux_bprm_committed_creds,
5414         .bprm_secureexec =              selinux_bprm_secureexec,
5415
5416         .sb_alloc_security =            selinux_sb_alloc_security,
5417         .sb_free_security =             selinux_sb_free_security,
5418         .sb_copy_data =                 selinux_sb_copy_data,
5419         .sb_kern_mount =                selinux_sb_kern_mount,
5420         .sb_show_options =              selinux_sb_show_options,
5421         .sb_statfs =                    selinux_sb_statfs,
5422         .sb_mount =                     selinux_mount,
5423         .sb_umount =                    selinux_umount,
5424         .sb_set_mnt_opts =              selinux_set_mnt_opts,
5425         .sb_clone_mnt_opts =            selinux_sb_clone_mnt_opts,
5426         .sb_parse_opts_str =            selinux_parse_opts_str,
5427
5428
5429         .inode_alloc_security =         selinux_inode_alloc_security,
5430         .inode_free_security =          selinux_inode_free_security,
5431         .inode_init_security =          selinux_inode_init_security,
5432         .inode_create =                 selinux_inode_create,
5433         .inode_link =                   selinux_inode_link,
5434         .inode_unlink =                 selinux_inode_unlink,
5435         .inode_symlink =                selinux_inode_symlink,
5436         .inode_mkdir =                  selinux_inode_mkdir,
5437         .inode_rmdir =                  selinux_inode_rmdir,
5438         .inode_mknod =                  selinux_inode_mknod,
5439         .inode_rename =                 selinux_inode_rename,
5440         .inode_readlink =               selinux_inode_readlink,
5441         .inode_follow_link =            selinux_inode_follow_link,
5442         .inode_permission =             selinux_inode_permission,
5443         .inode_setattr =                selinux_inode_setattr,
5444         .inode_getattr =                selinux_inode_getattr,
5445         .inode_setxattr =               selinux_inode_setxattr,
5446         .inode_post_setxattr =          selinux_inode_post_setxattr,
5447         .inode_getxattr =               selinux_inode_getxattr,
5448         .inode_listxattr =              selinux_inode_listxattr,
5449         .inode_removexattr =            selinux_inode_removexattr,
5450         .inode_getsecurity =            selinux_inode_getsecurity,
5451         .inode_setsecurity =            selinux_inode_setsecurity,
5452         .inode_listsecurity =           selinux_inode_listsecurity,
5453         .inode_getsecid =               selinux_inode_getsecid,
5454
5455         .file_permission =              selinux_file_permission,
5456         .file_alloc_security =          selinux_file_alloc_security,
5457         .file_free_security =           selinux_file_free_security,
5458         .file_ioctl =                   selinux_file_ioctl,
5459         .file_mmap =                    selinux_file_mmap,
5460         .file_mprotect =                selinux_file_mprotect,
5461         .file_lock =                    selinux_file_lock,
5462         .file_fcntl =                   selinux_file_fcntl,
5463         .file_set_fowner =              selinux_file_set_fowner,
5464         .file_send_sigiotask =          selinux_file_send_sigiotask,
5465         .file_receive =                 selinux_file_receive,
5466
5467         .dentry_open =                  selinux_dentry_open,
5468
5469         .task_create =                  selinux_task_create,
5470         .cred_alloc_blank =             selinux_cred_alloc_blank,
5471         .cred_free =                    selinux_cred_free,
5472         .cred_prepare =                 selinux_cred_prepare,
5473         .cred_transfer =                selinux_cred_transfer,
5474         .kernel_act_as =                selinux_kernel_act_as,
5475         .kernel_create_files_as =       selinux_kernel_create_files_as,
5476         .kernel_module_request =        selinux_kernel_module_request,
5477         .task_setpgid =                 selinux_task_setpgid,
5478         .task_getpgid =                 selinux_task_getpgid,
5479         .task_getsid =                  selinux_task_getsid,
5480         .task_getsecid =                selinux_task_getsecid,
5481         .task_setnice =                 selinux_task_setnice,
5482         .task_setioprio =               selinux_task_setioprio,
5483         .task_getioprio =               selinux_task_getioprio,
5484         .task_setrlimit =               selinux_task_setrlimit,
5485         .task_setscheduler =            selinux_task_setscheduler,
5486         .task_getscheduler =            selinux_task_getscheduler,
5487         .task_movememory =              selinux_task_movememory,
5488         .task_kill =                    selinux_task_kill,
5489         .task_wait =                    selinux_task_wait,
5490         .task_to_inode =                selinux_task_to_inode,
5491
5492         .ipc_permission =               selinux_ipc_permission,
5493         .ipc_getsecid =                 selinux_ipc_getsecid,
5494
5495         .msg_msg_alloc_security =       selinux_msg_msg_alloc_security,
5496         .msg_msg_free_security =        selinux_msg_msg_free_security,
5497
5498         .msg_queue_alloc_security =     selinux_msg_queue_alloc_security,
5499         .msg_queue_free_security =      selinux_msg_queue_free_security,
5500         .msg_queue_associate =          selinux_msg_queue_associate,
5501         .msg_queue_msgctl =             selinux_msg_queue_msgctl,
5502         .msg_queue_msgsnd =             selinux_msg_queue_msgsnd,
5503         .msg_queue_msgrcv =             selinux_msg_queue_msgrcv,
5504
5505         .shm_alloc_security =           selinux_shm_alloc_security,
5506         .shm_free_security =            selinux_shm_free_security,
5507         .shm_associate =                selinux_shm_associate,
5508         .shm_shmctl =                   selinux_shm_shmctl,
5509         .shm_shmat =                    selinux_shm_shmat,
5510
5511         .sem_alloc_security =           selinux_sem_alloc_security,
5512         .sem_free_security =            selinux_sem_free_security,
5513         .sem_associate =                selinux_sem_associate,
5514         .sem_semctl =                   selinux_sem_semctl,
5515         .sem_semop =                    selinux_sem_semop,
5516
5517         .d_instantiate =                selinux_d_instantiate,
5518
5519         .getprocattr =                  selinux_getprocattr,
5520         .setprocattr =                  selinux_setprocattr,
5521
5522         .secid_to_secctx =              selinux_secid_to_secctx,
5523         .secctx_to_secid =              selinux_secctx_to_secid,
5524         .release_secctx =               selinux_release_secctx,
5525         .inode_notifysecctx =           selinux_inode_notifysecctx,
5526         .inode_setsecctx =              selinux_inode_setsecctx,
5527         .inode_getsecctx =              selinux_inode_getsecctx,
5528
5529         .unix_stream_connect =          selinux_socket_unix_stream_connect,
5530         .unix_may_send =                selinux_socket_unix_may_send,
5531
5532         .socket_create =                selinux_socket_create,
5533         .socket_post_create =           selinux_socket_post_create,
5534         .socket_bind =                  selinux_socket_bind,
5535         .socket_connect =               selinux_socket_connect,
5536         .socket_listen =                selinux_socket_listen,
5537         .socket_accept =                selinux_socket_accept,
5538         .socket_sendmsg =               selinux_socket_sendmsg,
5539         .socket_recvmsg =               selinux_socket_recvmsg,
5540         .socket_getsockname =           selinux_socket_getsockname,
5541         .socket_getpeername =           selinux_socket_getpeername,
5542         .socket_getsockopt =            selinux_socket_getsockopt,
5543         .socket_setsockopt =            selinux_socket_setsockopt,
5544         .socket_shutdown =              selinux_socket_shutdown,
5545         .socket_sock_rcv_skb =          selinux_socket_sock_rcv_skb,
5546         .socket_getpeersec_stream =     selinux_socket_getpeersec_stream,
5547         .socket_getpeersec_dgram =      selinux_socket_getpeersec_dgram,
5548         .sk_alloc_security =            selinux_sk_alloc_security,
5549         .sk_free_security =             selinux_sk_free_security,
5550         .sk_clone_security =            selinux_sk_clone_security,
5551         .sk_getsecid =                  selinux_sk_getsecid,
5552         .sock_graft =                   selinux_sock_graft,
5553         .inet_conn_request =            selinux_inet_conn_request,
5554         .inet_csk_clone =               selinux_inet_csk_clone,
5555         .inet_conn_established =        selinux_inet_conn_established,
5556         .secmark_relabel_packet =       selinux_secmark_relabel_packet,
5557         .secmark_refcount_inc =         selinux_secmark_refcount_inc,
5558         .secmark_refcount_dec =         selinux_secmark_refcount_dec,
5559         .req_classify_flow =            selinux_req_classify_flow,
5560         .tun_dev_create =               selinux_tun_dev_create,
5561         .tun_dev_post_create =          selinux_tun_dev_post_create,
5562         .tun_dev_attach =               selinux_tun_dev_attach,
5563
5564 #ifdef CONFIG_SECURITY_NETWORK_XFRM
5565         .xfrm_policy_alloc_security =   selinux_xfrm_policy_alloc,
5566         .xfrm_policy_clone_security =   selinux_xfrm_policy_clone,
5567         .xfrm_policy_free_security =    selinux_xfrm_policy_free,
5568         .xfrm_policy_delete_security =  selinux_xfrm_policy_delete,
5569         .xfrm_state_alloc_security =    selinux_xfrm_state_alloc,
5570         .xfrm_state_free_security =     selinux_xfrm_state_free,
5571         .xfrm_state_delete_security =   selinux_xfrm_state_delete,
5572         .xfrm_policy_lookup =           selinux_xfrm_policy_lookup,
5573         .xfrm_state_pol_flow_match =    selinux_xfrm_state_pol_flow_match,
5574         .xfrm_decode_session =          selinux_xfrm_decode_session,
5575 #endif
5576
5577 #ifdef CONFIG_KEYS
5578         .key_alloc =                    selinux_key_alloc,
5579         .key_free =                     selinux_key_free,
5580         .key_permission =               selinux_key_permission,
5581         .key_getsecurity =              selinux_key_getsecurity,
5582 #endif
5583
5584 #ifdef CONFIG_AUDIT
5585         .audit_rule_init =              selinux_audit_rule_init,
5586         .audit_rule_known =             selinux_audit_rule_known,
5587         .audit_rule_match =             selinux_audit_rule_match,
5588         .audit_rule_free =              selinux_audit_rule_free,
5589 #endif
5590 };
5591
5592 static __init int selinux_init(void)
5593 {
5594         if (!security_module_enable(&selinux_ops)) {
5595                 selinux_enabled = 0;
5596                 return 0;
5597         }
5598
5599         if (!selinux_enabled) {
5600                 printk(KERN_INFO "SELinux:  Disabled at boot.\n");
5601                 return 0;
5602         }
5603
5604         printk(KERN_INFO "SELinux:  Initializing.\n");
5605
5606         /* Set the security state for the initial task. */
5607         cred_init_security();
5608
5609         default_noexec = !(VM_DATA_DEFAULT_FLAGS & VM_EXEC);
5610
5611         sel_inode_cache = kmem_cache_create("selinux_inode_security",
5612                                             sizeof(struct inode_security_struct),
5613                                             0, SLAB_PANIC, NULL);
5614         avc_init();
5615
5616         if (register_security(&selinux_ops))
5617                 panic("SELinux: Unable to register with kernel.\n");
5618
5619         if (selinux_enforcing)
5620                 printk(KERN_DEBUG "SELinux:  Starting in enforcing mode\n");
5621         else
5622                 printk(KERN_DEBUG "SELinux:  Starting in permissive mode\n");
5623
5624         return 0;
5625 }
5626
5627 static void delayed_superblock_init(struct super_block *sb, void *unused)
5628 {
5629         superblock_doinit(sb, NULL);
5630 }
5631
5632 void selinux_complete_init(void)
5633 {
5634         printk(KERN_DEBUG "SELinux:  Completing initialization.\n");
5635
5636         /* Set up any superblocks initialized prior to the policy load. */
5637         printk(KERN_DEBUG "SELinux:  Setting up existing superblocks.\n");
5638         iterate_supers(delayed_superblock_init, NULL);
5639 }
5640
5641 /* SELinux requires early initialization in order to label
5642    all processes and objects when they are created. */
5643 security_initcall(selinux_init);
5644
5645 #if defined(CONFIG_NETFILTER)
5646
5647 static struct nf_hook_ops selinux_ipv4_ops[] = {
5648         {
5649                 .hook =         selinux_ipv4_postroute,
5650                 .owner =        THIS_MODULE,
5651                 .pf =           PF_INET,
5652                 .hooknum =      NF_INET_POST_ROUTING,
5653                 .priority =     NF_IP_PRI_SELINUX_LAST,
5654         },
5655         {
5656                 .hook =         selinux_ipv4_forward,
5657                 .owner =        THIS_MODULE,
5658                 .pf =           PF_INET,
5659                 .hooknum =      NF_INET_FORWARD,
5660                 .priority =     NF_IP_PRI_SELINUX_FIRST,
5661         },
5662         {
5663                 .hook =         selinux_ipv4_output,
5664                 .owner =        THIS_MODULE,
5665                 .pf =           PF_INET,
5666                 .hooknum =      NF_INET_LOCAL_OUT,
5667                 .priority =     NF_IP_PRI_SELINUX_FIRST,
5668         }
5669 };
5670
5671 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
5672
5673 static struct nf_hook_ops selinux_ipv6_ops[] = {
5674         {
5675                 .hook =         selinux_ipv6_postroute,
5676                 .owner =        THIS_MODULE,
5677                 .pf =           PF_INET6,
5678                 .hooknum =      NF_INET_POST_ROUTING,
5679                 .priority =     NF_IP6_PRI_SELINUX_LAST,
5680         },
5681         {
5682                 .hook =         selinux_ipv6_forward,
5683                 .owner =        THIS_MODULE,
5684                 .pf =           PF_INET6,
5685                 .hooknum =      NF_INET_FORWARD,
5686                 .priority =     NF_IP6_PRI_SELINUX_FIRST,
5687         }
5688 };
5689
5690 #endif  /* IPV6 */
5691
5692 static int __init selinux_nf_ip_init(void)
5693 {
5694         int err = 0;
5695
5696         if (!selinux_enabled)
5697                 goto out;
5698
5699         printk(KERN_DEBUG "SELinux:  Registering netfilter hooks\n");
5700
5701         err = nf_register_hooks(selinux_ipv4_ops, ARRAY_SIZE(selinux_ipv4_ops));
5702         if (err)
5703                 panic("SELinux: nf_register_hooks for IPv4: error %d\n", err);
5704
5705 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
5706         err = nf_register_hooks(selinux_ipv6_ops, ARRAY_SIZE(selinux_ipv6_ops));
5707         if (err)
5708                 panic("SELinux: nf_register_hooks for IPv6: error %d\n", err);
5709 #endif  /* IPV6 */
5710
5711 out:
5712         return err;
5713 }
5714
5715 __initcall(selinux_nf_ip_init);
5716
5717 #ifdef CONFIG_SECURITY_SELINUX_DISABLE
5718 static void selinux_nf_ip_exit(void)
5719 {
5720         printk(KERN_DEBUG "SELinux:  Unregistering netfilter hooks\n");
5721
5722         nf_unregister_hooks(selinux_ipv4_ops, ARRAY_SIZE(selinux_ipv4_ops));
5723 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
5724         nf_unregister_hooks(selinux_ipv6_ops, ARRAY_SIZE(selinux_ipv6_ops));
5725 #endif  /* IPV6 */
5726 }
5727 #endif
5728
5729 #else /* CONFIG_NETFILTER */
5730
5731 #ifdef CONFIG_SECURITY_SELINUX_DISABLE
5732 #define selinux_nf_ip_exit()
5733 #endif
5734
5735 #endif /* CONFIG_NETFILTER */
5736
5737 #ifdef CONFIG_SECURITY_SELINUX_DISABLE
5738 static int selinux_disabled;
5739
5740 int selinux_disable(void)
5741 {
5742         extern void exit_sel_fs(void);
5743
5744         if (ss_initialized) {
5745                 /* Not permitted after initial policy load. */
5746                 return -EINVAL;
5747         }
5748
5749         if (selinux_disabled) {
5750                 /* Only do this once. */
5751                 return -EINVAL;
5752         }
5753
5754         printk(KERN_INFO "SELinux:  Disabled at runtime.\n");
5755
5756         selinux_disabled = 1;
5757         selinux_enabled = 0;
5758
5759         reset_security_ops();
5760
5761         /* Try to destroy the avc node cache */
5762         avc_disable();
5763
5764         /* Unregister netfilter hooks. */
5765         selinux_nf_ip_exit();
5766
5767         /* Unregister selinuxfs. */
5768         exit_sel_fs();
5769
5770         return 0;
5771 }
5772 #endif