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         /*
3202          * cred->security == NULL if security_cred_alloc_blank() or
3203          * security_prepare_creds() returned an error.
3204          */
3205         BUG_ON(cred->security && (unsigned long) cred->security < PAGE_SIZE);
3206         cred->security = (void *) 0x7UL;
3207         kfree(tsec);
3208 }
3209
3210 /*
3211  * prepare a new set of credentials for modification
3212  */
3213 static int selinux_cred_prepare(struct cred *new, const struct cred *old,
3214                                 gfp_t gfp)
3215 {
3216         const struct task_security_struct *old_tsec;
3217         struct task_security_struct *tsec;
3218
3219         old_tsec = old->security;
3220
3221         tsec = kmemdup(old_tsec, sizeof(struct task_security_struct), gfp);
3222         if (!tsec)
3223                 return -ENOMEM;
3224
3225         new->security = tsec;
3226         return 0;
3227 }
3228
3229 /*
3230  * transfer the SELinux data to a blank set of creds
3231  */
3232 static void selinux_cred_transfer(struct cred *new, const struct cred *old)
3233 {
3234         const struct task_security_struct *old_tsec = old->security;
3235         struct task_security_struct *tsec = new->security;
3236
3237         *tsec = *old_tsec;
3238 }
3239
3240 /*
3241  * set the security data for a kernel service
3242  * - all the creation contexts are set to unlabelled
3243  */
3244 static int selinux_kernel_act_as(struct cred *new, u32 secid)
3245 {
3246         struct task_security_struct *tsec = new->security;
3247         u32 sid = current_sid();
3248         int ret;
3249
3250         ret = avc_has_perm(sid, secid,
3251                            SECCLASS_KERNEL_SERVICE,
3252                            KERNEL_SERVICE__USE_AS_OVERRIDE,
3253                            NULL);
3254         if (ret == 0) {
3255                 tsec->sid = secid;
3256                 tsec->create_sid = 0;
3257                 tsec->keycreate_sid = 0;
3258                 tsec->sockcreate_sid = 0;
3259         }
3260         return ret;
3261 }
3262
3263 /*
3264  * set the file creation context in a security record to the same as the
3265  * objective context of the specified inode
3266  */
3267 static int selinux_kernel_create_files_as(struct cred *new, struct inode *inode)
3268 {
3269         struct inode_security_struct *isec = inode->i_security;
3270         struct task_security_struct *tsec = new->security;
3271         u32 sid = current_sid();
3272         int ret;
3273
3274         ret = avc_has_perm(sid, isec->sid,
3275                            SECCLASS_KERNEL_SERVICE,
3276                            KERNEL_SERVICE__CREATE_FILES_AS,
3277                            NULL);
3278
3279         if (ret == 0)
3280                 tsec->create_sid = isec->sid;
3281         return ret;
3282 }
3283
3284 static int selinux_kernel_module_request(char *kmod_name)
3285 {
3286         u32 sid;
3287         struct common_audit_data ad;
3288
3289         sid = task_sid(current);
3290
3291         COMMON_AUDIT_DATA_INIT(&ad, KMOD);
3292         ad.u.kmod_name = kmod_name;
3293
3294         return avc_has_perm(sid, SECINITSID_KERNEL, SECCLASS_SYSTEM,
3295                             SYSTEM__MODULE_REQUEST, &ad);
3296 }
3297
3298 static int selinux_task_setpgid(struct task_struct *p, pid_t pgid)
3299 {
3300         return current_has_perm(p, PROCESS__SETPGID);
3301 }
3302
3303 static int selinux_task_getpgid(struct task_struct *p)
3304 {
3305         return current_has_perm(p, PROCESS__GETPGID);
3306 }
3307
3308 static int selinux_task_getsid(struct task_struct *p)
3309 {
3310         return current_has_perm(p, PROCESS__GETSESSION);
3311 }
3312
3313 static void selinux_task_getsecid(struct task_struct *p, u32 *secid)
3314 {
3315         *secid = task_sid(p);
3316 }
3317
3318 static int selinux_task_setnice(struct task_struct *p, int nice)
3319 {
3320         int rc;
3321
3322         rc = cap_task_setnice(p, nice);
3323         if (rc)
3324                 return rc;
3325
3326         return current_has_perm(p, PROCESS__SETSCHED);
3327 }
3328
3329 static int selinux_task_setioprio(struct task_struct *p, int ioprio)
3330 {
3331         int rc;
3332
3333         rc = cap_task_setioprio(p, ioprio);
3334         if (rc)
3335                 return rc;
3336
3337         return current_has_perm(p, PROCESS__SETSCHED);
3338 }
3339
3340 static int selinux_task_getioprio(struct task_struct *p)
3341 {
3342         return current_has_perm(p, PROCESS__GETSCHED);
3343 }
3344
3345 static int selinux_task_setrlimit(struct task_struct *p, unsigned int resource,
3346                 struct rlimit *new_rlim)
3347 {
3348         struct rlimit *old_rlim = p->signal->rlim + resource;
3349
3350         /* Control the ability to change the hard limit (whether
3351            lowering or raising it), so that the hard limit can
3352            later be used as a safe reset point for the soft limit
3353            upon context transitions.  See selinux_bprm_committing_creds. */
3354         if (old_rlim->rlim_max != new_rlim->rlim_max)
3355                 return current_has_perm(p, PROCESS__SETRLIMIT);
3356
3357         return 0;
3358 }
3359
3360 static int selinux_task_setscheduler(struct task_struct *p)
3361 {
3362         int rc;
3363
3364         rc = cap_task_setscheduler(p);
3365         if (rc)
3366                 return rc;
3367
3368         return current_has_perm(p, PROCESS__SETSCHED);
3369 }
3370
3371 static int selinux_task_getscheduler(struct task_struct *p)
3372 {
3373         return current_has_perm(p, PROCESS__GETSCHED);
3374 }
3375
3376 static int selinux_task_movememory(struct task_struct *p)
3377 {
3378         return current_has_perm(p, PROCESS__SETSCHED);
3379 }
3380
3381 static int selinux_task_kill(struct task_struct *p, struct siginfo *info,
3382                                 int sig, u32 secid)
3383 {
3384         u32 perm;
3385         int rc;
3386
3387         if (!sig)
3388                 perm = PROCESS__SIGNULL; /* null signal; existence test */
3389         else
3390                 perm = signal_to_av(sig);
3391         if (secid)
3392                 rc = avc_has_perm(secid, task_sid(p),
3393                                   SECCLASS_PROCESS, perm, NULL);
3394         else
3395                 rc = current_has_perm(p, perm);
3396         return rc;
3397 }
3398
3399 static int selinux_task_wait(struct task_struct *p)
3400 {
3401         return task_has_perm(p, current, PROCESS__SIGCHLD);
3402 }
3403
3404 static void selinux_task_to_inode(struct task_struct *p,
3405                                   struct inode *inode)
3406 {
3407         struct inode_security_struct *isec = inode->i_security;
3408         u32 sid = task_sid(p);
3409
3410         isec->sid = sid;
3411         isec->initialized = 1;
3412 }
3413
3414 /* Returns error only if unable to parse addresses */
3415 static int selinux_parse_skb_ipv4(struct sk_buff *skb,
3416                         struct common_audit_data *ad, u8 *proto)
3417 {
3418         int offset, ihlen, ret = -EINVAL;
3419         struct iphdr _iph, *ih;
3420
3421         offset = skb_network_offset(skb);
3422         ih = skb_header_pointer(skb, offset, sizeof(_iph), &_iph);
3423         if (ih == NULL)
3424                 goto out;
3425
3426         ihlen = ih->ihl * 4;
3427         if (ihlen < sizeof(_iph))
3428                 goto out;
3429
3430         ad->u.net.v4info.saddr = ih->saddr;
3431         ad->u.net.v4info.daddr = ih->daddr;
3432         ret = 0;
3433
3434         if (proto)
3435                 *proto = ih->protocol;
3436
3437         switch (ih->protocol) {
3438         case IPPROTO_TCP: {
3439                 struct tcphdr _tcph, *th;
3440
3441                 if (ntohs(ih->frag_off) & IP_OFFSET)
3442                         break;
3443
3444                 offset += ihlen;
3445                 th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph);
3446                 if (th == NULL)
3447                         break;
3448
3449                 ad->u.net.sport = th->source;
3450                 ad->u.net.dport = th->dest;
3451                 break;
3452         }
3453
3454         case IPPROTO_UDP: {
3455                 struct udphdr _udph, *uh;
3456
3457                 if (ntohs(ih->frag_off) & IP_OFFSET)
3458                         break;
3459
3460                 offset += ihlen;
3461                 uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph);
3462                 if (uh == NULL)
3463                         break;
3464
3465                 ad->u.net.sport = uh->source;
3466                 ad->u.net.dport = uh->dest;
3467                 break;
3468         }
3469
3470         case IPPROTO_DCCP: {
3471                 struct dccp_hdr _dccph, *dh;
3472
3473                 if (ntohs(ih->frag_off) & IP_OFFSET)
3474                         break;
3475
3476                 offset += ihlen;
3477                 dh = skb_header_pointer(skb, offset, sizeof(_dccph), &_dccph);
3478                 if (dh == NULL)
3479                         break;
3480
3481                 ad->u.net.sport = dh->dccph_sport;
3482                 ad->u.net.dport = dh->dccph_dport;
3483                 break;
3484         }
3485
3486         default:
3487                 break;
3488         }
3489 out:
3490         return ret;
3491 }
3492
3493 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
3494
3495 /* Returns error only if unable to parse addresses */
3496 static int selinux_parse_skb_ipv6(struct sk_buff *skb,
3497                         struct common_audit_data *ad, u8 *proto)
3498 {
3499         u8 nexthdr;
3500         int ret = -EINVAL, offset;
3501         struct ipv6hdr _ipv6h, *ip6;
3502
3503         offset = skb_network_offset(skb);
3504         ip6 = skb_header_pointer(skb, offset, sizeof(_ipv6h), &_ipv6h);
3505         if (ip6 == NULL)
3506                 goto out;
3507
3508         ipv6_addr_copy(&ad->u.net.v6info.saddr, &ip6->saddr);
3509         ipv6_addr_copy(&ad->u.net.v6info.daddr, &ip6->daddr);
3510         ret = 0;
3511
3512         nexthdr = ip6->nexthdr;
3513         offset += sizeof(_ipv6h);
3514         offset = ipv6_skip_exthdr(skb, offset, &nexthdr);
3515         if (offset < 0)
3516                 goto out;
3517
3518         if (proto)
3519                 *proto = nexthdr;
3520
3521         switch (nexthdr) {
3522         case IPPROTO_TCP: {
3523                 struct tcphdr _tcph, *th;
3524
3525                 th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph);
3526                 if (th == NULL)
3527                         break;
3528
3529                 ad->u.net.sport = th->source;
3530                 ad->u.net.dport = th->dest;
3531                 break;
3532         }
3533
3534         case IPPROTO_UDP: {
3535                 struct udphdr _udph, *uh;
3536
3537                 uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph);
3538                 if (uh == NULL)
3539                         break;
3540
3541                 ad->u.net.sport = uh->source;
3542                 ad->u.net.dport = uh->dest;
3543                 break;
3544         }
3545
3546         case IPPROTO_DCCP: {
3547                 struct dccp_hdr _dccph, *dh;
3548
3549                 dh = skb_header_pointer(skb, offset, sizeof(_dccph), &_dccph);
3550                 if (dh == NULL)
3551                         break;
3552
3553                 ad->u.net.sport = dh->dccph_sport;
3554                 ad->u.net.dport = dh->dccph_dport;
3555                 break;
3556         }
3557
3558         /* includes fragments */
3559         default:
3560                 break;
3561         }
3562 out:
3563         return ret;
3564 }
3565
3566 #endif /* IPV6 */
3567
3568 static int selinux_parse_skb(struct sk_buff *skb, struct common_audit_data *ad,
3569                              char **_addrp, int src, u8 *proto)
3570 {
3571         char *addrp;
3572         int ret;
3573
3574         switch (ad->u.net.family) {
3575         case PF_INET:
3576                 ret = selinux_parse_skb_ipv4(skb, ad, proto);
3577                 if (ret)
3578                         goto parse_error;
3579                 addrp = (char *)(src ? &ad->u.net.v4info.saddr :
3580                                        &ad->u.net.v4info.daddr);
3581                 goto okay;
3582
3583 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
3584         case PF_INET6:
3585                 ret = selinux_parse_skb_ipv6(skb, ad, proto);
3586                 if (ret)
3587                         goto parse_error;
3588                 addrp = (char *)(src ? &ad->u.net.v6info.saddr :
3589                                        &ad->u.net.v6info.daddr);
3590                 goto okay;
3591 #endif  /* IPV6 */
3592         default:
3593                 addrp = NULL;
3594                 goto okay;
3595         }
3596
3597 parse_error:
3598         printk(KERN_WARNING
3599                "SELinux: failure in selinux_parse_skb(),"
3600                " unable to parse packet\n");
3601         return ret;
3602
3603 okay:
3604         if (_addrp)
3605                 *_addrp = addrp;
3606         return 0;
3607 }
3608
3609 /**
3610  * selinux_skb_peerlbl_sid - Determine the peer label of a packet
3611  * @skb: the packet
3612  * @family: protocol family
3613  * @sid: the packet's peer label SID
3614  *
3615  * Description:
3616  * Check the various different forms of network peer labeling and determine
3617  * the peer label/SID for the packet; most of the magic actually occurs in
3618  * the security server function security_net_peersid_cmp().  The function
3619  * returns zero if the value in @sid is valid (although it may be SECSID_NULL)
3620  * or -EACCES if @sid is invalid due to inconsistencies with the different
3621  * peer labels.
3622  *
3623  */
3624 static int selinux_skb_peerlbl_sid(struct sk_buff *skb, u16 family, u32 *sid)
3625 {
3626         int err;
3627         u32 xfrm_sid;
3628         u32 nlbl_sid;
3629         u32 nlbl_type;
3630
3631         selinux_skb_xfrm_sid(skb, &xfrm_sid);
3632         selinux_netlbl_skbuff_getsid(skb, family, &nlbl_type, &nlbl_sid);
3633
3634         err = security_net_peersid_resolve(nlbl_sid, nlbl_type, xfrm_sid, sid);
3635         if (unlikely(err)) {
3636                 printk(KERN_WARNING
3637                        "SELinux: failure in selinux_skb_peerlbl_sid(),"
3638                        " unable to determine packet's peer label\n");
3639                 return -EACCES;
3640         }
3641
3642         return 0;
3643 }
3644
3645 /* socket security operations */
3646
3647 static u32 socket_sockcreate_sid(const struct task_security_struct *tsec)
3648 {
3649         return tsec->sockcreate_sid ? : tsec->sid;
3650 }
3651
3652 static int sock_has_perm(struct task_struct *task, struct sock *sk, u32 perms)
3653 {
3654         struct sk_security_struct *sksec = sk->sk_security;
3655         struct common_audit_data ad;
3656         u32 tsid = task_sid(task);
3657
3658         if (sksec->sid == SECINITSID_KERNEL)
3659                 return 0;
3660
3661         COMMON_AUDIT_DATA_INIT(&ad, NET);
3662         ad.u.net.sk = sk;
3663
3664         return avc_has_perm(tsid, sksec->sid, sksec->sclass, perms, &ad);
3665 }
3666
3667 static int selinux_socket_create(int family, int type,
3668                                  int protocol, int kern)
3669 {
3670         const struct task_security_struct *tsec = current_security();
3671         u32 newsid;
3672         u16 secclass;
3673
3674         if (kern)
3675                 return 0;
3676
3677         newsid = socket_sockcreate_sid(tsec);
3678         secclass = socket_type_to_security_class(family, type, protocol);
3679         return avc_has_perm(tsec->sid, newsid, secclass, SOCKET__CREATE, NULL);
3680 }
3681
3682 static int selinux_socket_post_create(struct socket *sock, int family,
3683                                       int type, int protocol, int kern)
3684 {
3685         const struct task_security_struct *tsec = current_security();
3686         struct inode_security_struct *isec = SOCK_INODE(sock)->i_security;
3687         struct sk_security_struct *sksec;
3688         int err = 0;
3689
3690         if (kern)
3691                 isec->sid = SECINITSID_KERNEL;
3692         else
3693                 isec->sid = socket_sockcreate_sid(tsec);
3694
3695         isec->sclass = socket_type_to_security_class(family, type, protocol);
3696         isec->initialized = 1;
3697
3698         if (sock->sk) {
3699                 sksec = sock->sk->sk_security;
3700                 sksec->sid = isec->sid;
3701                 sksec->sclass = isec->sclass;
3702                 err = selinux_netlbl_socket_post_create(sock->sk, family);
3703         }
3704
3705         return err;
3706 }
3707
3708 /* Range of port numbers used to automatically bind.
3709    Need to determine whether we should perform a name_bind
3710    permission check between the socket and the port number. */
3711
3712 static int selinux_socket_bind(struct socket *sock, struct sockaddr *address, int addrlen)
3713 {
3714         struct sock *sk = sock->sk;
3715         u16 family;
3716         int err;
3717
3718         err = sock_has_perm(current, sk, SOCKET__BIND);
3719         if (err)
3720                 goto out;
3721
3722         /*
3723          * If PF_INET or PF_INET6, check name_bind permission for the port.
3724          * Multiple address binding for SCTP is not supported yet: we just
3725          * check the first address now.
3726          */
3727         family = sk->sk_family;
3728         if (family == PF_INET || family == PF_INET6) {
3729                 char *addrp;
3730                 struct sk_security_struct *sksec = sk->sk_security;
3731                 struct common_audit_data ad;
3732                 struct sockaddr_in *addr4 = NULL;
3733                 struct sockaddr_in6 *addr6 = NULL;
3734                 unsigned short snum;
3735                 u32 sid, node_perm;
3736
3737                 if (family == PF_INET) {
3738                         addr4 = (struct sockaddr_in *)address;
3739                         snum = ntohs(addr4->sin_port);
3740                         addrp = (char *)&addr4->sin_addr.s_addr;
3741                 } else {
3742                         addr6 = (struct sockaddr_in6 *)address;
3743                         snum = ntohs(addr6->sin6_port);
3744                         addrp = (char *)&addr6->sin6_addr.s6_addr;
3745                 }
3746
3747                 if (snum) {
3748                         int low, high;
3749
3750                         inet_get_local_port_range(&low, &high);
3751
3752                         if (snum < max(PROT_SOCK, low) || snum > high) {
3753                                 err = sel_netport_sid(sk->sk_protocol,
3754                                                       snum, &sid);
3755                                 if (err)
3756                                         goto out;
3757                                 COMMON_AUDIT_DATA_INIT(&ad, NET);
3758                                 ad.u.net.sport = htons(snum);
3759                                 ad.u.net.family = family;
3760                                 err = avc_has_perm(sksec->sid, sid,
3761                                                    sksec->sclass,
3762                                                    SOCKET__NAME_BIND, &ad);
3763                                 if (err)
3764                                         goto out;
3765                         }
3766                 }
3767
3768                 switch (sksec->sclass) {
3769                 case SECCLASS_TCP_SOCKET:
3770                         node_perm = TCP_SOCKET__NODE_BIND;
3771                         break;
3772
3773                 case SECCLASS_UDP_SOCKET:
3774                         node_perm = UDP_SOCKET__NODE_BIND;
3775                         break;
3776
3777                 case SECCLASS_DCCP_SOCKET:
3778                         node_perm = DCCP_SOCKET__NODE_BIND;
3779                         break;
3780
3781                 default:
3782                         node_perm = RAWIP_SOCKET__NODE_BIND;
3783                         break;
3784                 }
3785
3786                 err = sel_netnode_sid(addrp, family, &sid);
3787                 if (err)
3788                         goto out;
3789
3790                 COMMON_AUDIT_DATA_INIT(&ad, NET);
3791                 ad.u.net.sport = htons(snum);
3792                 ad.u.net.family = family;
3793
3794                 if (family == PF_INET)
3795                         ad.u.net.v4info.saddr = addr4->sin_addr.s_addr;
3796                 else
3797                         ipv6_addr_copy(&ad.u.net.v6info.saddr, &addr6->sin6_addr);
3798
3799                 err = avc_has_perm(sksec->sid, sid,
3800                                    sksec->sclass, node_perm, &ad);
3801                 if (err)
3802                         goto out;
3803         }
3804 out:
3805         return err;
3806 }
3807
3808 static int selinux_socket_connect(struct socket *sock, struct sockaddr *address, int addrlen)
3809 {
3810         struct sock *sk = sock->sk;
3811         struct sk_security_struct *sksec = sk->sk_security;
3812         int err;
3813
3814         err = sock_has_perm(current, sk, SOCKET__CONNECT);
3815         if (err)
3816                 return err;
3817
3818         /*
3819          * If a TCP or DCCP socket, check name_connect permission for the port.
3820          */
3821         if (sksec->sclass == SECCLASS_TCP_SOCKET ||
3822             sksec->sclass == SECCLASS_DCCP_SOCKET) {
3823                 struct common_audit_data ad;
3824                 struct sockaddr_in *addr4 = NULL;
3825                 struct sockaddr_in6 *addr6 = NULL;
3826                 unsigned short snum;
3827                 u32 sid, perm;
3828
3829                 if (sk->sk_family == PF_INET) {
3830                         addr4 = (struct sockaddr_in *)address;
3831                         if (addrlen < sizeof(struct sockaddr_in))
3832                                 return -EINVAL;
3833                         snum = ntohs(addr4->sin_port);
3834                 } else {
3835                         addr6 = (struct sockaddr_in6 *)address;
3836                         if (addrlen < SIN6_LEN_RFC2133)
3837                                 return -EINVAL;
3838                         snum = ntohs(addr6->sin6_port);
3839                 }
3840
3841                 err = sel_netport_sid(sk->sk_protocol, snum, &sid);
3842                 if (err)
3843                         goto out;
3844
3845                 perm = (sksec->sclass == SECCLASS_TCP_SOCKET) ?
3846                        TCP_SOCKET__NAME_CONNECT : DCCP_SOCKET__NAME_CONNECT;
3847
3848                 COMMON_AUDIT_DATA_INIT(&ad, NET);
3849                 ad.u.net.dport = htons(snum);
3850                 ad.u.net.family = sk->sk_family;
3851                 err = avc_has_perm(sksec->sid, sid, sksec->sclass, perm, &ad);
3852                 if (err)
3853                         goto out;
3854         }
3855
3856         err = selinux_netlbl_socket_connect(sk, address);
3857
3858 out:
3859         return err;
3860 }
3861
3862 static int selinux_socket_listen(struct socket *sock, int backlog)
3863 {
3864         return sock_has_perm(current, sock->sk, SOCKET__LISTEN);
3865 }
3866
3867 static int selinux_socket_accept(struct socket *sock, struct socket *newsock)
3868 {
3869         int err;
3870         struct inode_security_struct *isec;
3871         struct inode_security_struct *newisec;
3872
3873         err = sock_has_perm(current, sock->sk, SOCKET__ACCEPT);
3874         if (err)
3875                 return err;
3876
3877         newisec = SOCK_INODE(newsock)->i_security;
3878
3879         isec = SOCK_INODE(sock)->i_security;
3880         newisec->sclass = isec->sclass;
3881         newisec->sid = isec->sid;
3882         newisec->initialized = 1;
3883
3884         return 0;
3885 }
3886
3887 static int selinux_socket_sendmsg(struct socket *sock, struct msghdr *msg,
3888                                   int size)
3889 {
3890         return sock_has_perm(current, sock->sk, SOCKET__WRITE);
3891 }
3892
3893 static int selinux_socket_recvmsg(struct socket *sock, struct msghdr *msg,
3894                                   int size, int flags)
3895 {
3896         return sock_has_perm(current, sock->sk, SOCKET__READ);
3897 }
3898
3899 static int selinux_socket_getsockname(struct socket *sock)
3900 {
3901         return sock_has_perm(current, sock->sk, SOCKET__GETATTR);
3902 }
3903
3904 static int selinux_socket_getpeername(struct socket *sock)
3905 {
3906         return sock_has_perm(current, sock->sk, SOCKET__GETATTR);
3907 }
3908
3909 static int selinux_socket_setsockopt(struct socket *sock, int level, int optname)
3910 {
3911         int err;
3912
3913         err = sock_has_perm(current, sock->sk, SOCKET__SETOPT);
3914         if (err)
3915                 return err;
3916
3917         return selinux_netlbl_socket_setsockopt(sock, level, optname);
3918 }
3919
3920 static int selinux_socket_getsockopt(struct socket *sock, int level,
3921                                      int optname)
3922 {
3923         return sock_has_perm(current, sock->sk, SOCKET__GETOPT);
3924 }
3925
3926 static int selinux_socket_shutdown(struct socket *sock, int how)
3927 {
3928         return sock_has_perm(current, sock->sk, SOCKET__SHUTDOWN);
3929 }
3930
3931 static int selinux_socket_unix_stream_connect(struct sock *sock,
3932                                               struct sock *other,
3933                                               struct sock *newsk)
3934 {
3935         struct sk_security_struct *sksec_sock = sock->sk_security;
3936         struct sk_security_struct *sksec_other = other->sk_security;
3937         struct sk_security_struct *sksec_new = newsk->sk_security;
3938         struct common_audit_data ad;
3939         int err;
3940
3941         COMMON_AUDIT_DATA_INIT(&ad, NET);
3942         ad.u.net.sk = other;
3943
3944         err = avc_has_perm(sksec_sock->sid, sksec_other->sid,
3945                            sksec_other->sclass,
3946                            UNIX_STREAM_SOCKET__CONNECTTO, &ad);
3947         if (err)
3948                 return err;
3949
3950         /* server child socket */
3951         sksec_new->peer_sid = sksec_sock->sid;
3952         err = security_sid_mls_copy(sksec_other->sid, sksec_sock->sid,
3953                                     &sksec_new->sid);
3954         if (err)
3955                 return err;
3956
3957         /* connecting socket */
3958         sksec_sock->peer_sid = sksec_new->sid;
3959
3960         return 0;
3961 }
3962
3963 static int selinux_socket_unix_may_send(struct socket *sock,
3964                                         struct socket *other)
3965 {
3966         struct sk_security_struct *ssec = sock->sk->sk_security;
3967         struct sk_security_struct *osec = other->sk->sk_security;
3968         struct common_audit_data ad;
3969
3970         COMMON_AUDIT_DATA_INIT(&ad, NET);
3971         ad.u.net.sk = other->sk;
3972
3973         return avc_has_perm(ssec->sid, osec->sid, osec->sclass, SOCKET__SENDTO,
3974                             &ad);
3975 }
3976
3977 static int selinux_inet_sys_rcv_skb(int ifindex, char *addrp, u16 family,
3978                                     u32 peer_sid,
3979                                     struct common_audit_data *ad)
3980 {
3981         int err;
3982         u32 if_sid;
3983         u32 node_sid;
3984
3985         err = sel_netif_sid(ifindex, &if_sid);
3986         if (err)
3987                 return err;
3988         err = avc_has_perm(peer_sid, if_sid,
3989                            SECCLASS_NETIF, NETIF__INGRESS, ad);
3990         if (err)
3991                 return err;
3992
3993         err = sel_netnode_sid(addrp, family, &node_sid);
3994         if (err)
3995                 return err;
3996         return avc_has_perm(peer_sid, node_sid,
3997                             SECCLASS_NODE, NODE__RECVFROM, ad);
3998 }
3999
4000 static int selinux_sock_rcv_skb_compat(struct sock *sk, struct sk_buff *skb,
4001                                        u16 family)
4002 {
4003         int err = 0;
4004         struct sk_security_struct *sksec = sk->sk_security;
4005         u32 peer_sid;
4006         u32 sk_sid = sksec->sid;
4007         struct common_audit_data ad;
4008         char *addrp;
4009
4010         COMMON_AUDIT_DATA_INIT(&ad, NET);
4011         ad.u.net.netif = skb->skb_iif;
4012         ad.u.net.family = family;
4013         err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL);
4014         if (err)
4015                 return err;
4016
4017         if (selinux_secmark_enabled()) {
4018                 err = avc_has_perm(sk_sid, skb->secmark, SECCLASS_PACKET,
4019                                    PACKET__RECV, &ad);
4020                 if (err)
4021                         return err;
4022         }
4023
4024         if (selinux_policycap_netpeer) {
4025                 err = selinux_skb_peerlbl_sid(skb, family, &peer_sid);
4026                 if (err)
4027                         return err;
4028                 err = avc_has_perm(sk_sid, peer_sid,
4029                                    SECCLASS_PEER, PEER__RECV, &ad);
4030                 if (err)
4031                         selinux_netlbl_err(skb, err, 0);
4032         } else {
4033                 err = selinux_netlbl_sock_rcv_skb(sksec, skb, family, &ad);
4034                 if (err)
4035                         return err;
4036                 err = selinux_xfrm_sock_rcv_skb(sksec->sid, skb, &ad);
4037         }
4038
4039         return err;
4040 }
4041
4042 static int selinux_socket_sock_rcv_skb(struct sock *sk, struct sk_buff *skb)
4043 {
4044         int err;
4045         struct sk_security_struct *sksec = sk->sk_security;
4046         u16 family = sk->sk_family;
4047         u32 sk_sid = sksec->sid;
4048         struct common_audit_data ad;
4049         char *addrp;
4050         u8 secmark_active;
4051         u8 peerlbl_active;
4052
4053         if (family != PF_INET && family != PF_INET6)
4054                 return 0;
4055
4056         /* Handle mapped IPv4 packets arriving via IPv6 sockets */
4057         if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
4058                 family = PF_INET;
4059
4060         /* If any sort of compatibility mode is enabled then handoff processing
4061          * to the selinux_sock_rcv_skb_compat() function to deal with the
4062          * special handling.  We do this in an attempt to keep this function
4063          * as fast and as clean as possible. */
4064         if (!selinux_policycap_netpeer)
4065                 return selinux_sock_rcv_skb_compat(sk, skb, family);
4066
4067         secmark_active = selinux_secmark_enabled();
4068         peerlbl_active = netlbl_enabled() || selinux_xfrm_enabled();
4069         if (!secmark_active && !peerlbl_active)
4070                 return 0;
4071
4072         COMMON_AUDIT_DATA_INIT(&ad, NET);
4073         ad.u.net.netif = skb->skb_iif;
4074         ad.u.net.family = family;
4075         err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL);
4076         if (err)
4077                 return err;
4078
4079         if (peerlbl_active) {
4080                 u32 peer_sid;
4081
4082                 err = selinux_skb_peerlbl_sid(skb, family, &peer_sid);
4083                 if (err)
4084                         return err;
4085                 err = selinux_inet_sys_rcv_skb(skb->skb_iif, addrp, family,
4086                                                peer_sid, &ad);
4087                 if (err) {
4088                         selinux_netlbl_err(skb, err, 0);
4089                         return err;
4090                 }
4091                 err = avc_has_perm(sk_sid, peer_sid, SECCLASS_PEER,
4092                                    PEER__RECV, &ad);
4093                 if (err)
4094                         selinux_netlbl_err(skb, err, 0);
4095         }
4096
4097         if (secmark_active) {
4098                 err = avc_has_perm(sk_sid, skb->secmark, SECCLASS_PACKET,
4099                                    PACKET__RECV, &ad);
4100                 if (err)
4101                         return err;
4102         }
4103
4104         return err;
4105 }
4106
4107 static int selinux_socket_getpeersec_stream(struct socket *sock, char __user *optval,
4108                                             int __user *optlen, unsigned len)
4109 {
4110         int err = 0;
4111         char *scontext;
4112         u32 scontext_len;
4113         struct sk_security_struct *sksec = sock->sk->sk_security;
4114         u32 peer_sid = SECSID_NULL;
4115
4116         if (sksec->sclass == SECCLASS_UNIX_STREAM_SOCKET ||
4117             sksec->sclass == SECCLASS_TCP_SOCKET)
4118                 peer_sid = sksec->peer_sid;
4119         if (peer_sid == SECSID_NULL)
4120                 return -ENOPROTOOPT;
4121
4122         err = security_sid_to_context(peer_sid, &scontext, &scontext_len);
4123         if (err)
4124                 return err;
4125
4126         if (scontext_len > len) {
4127                 err = -ERANGE;
4128                 goto out_len;
4129         }
4130
4131         if (copy_to_user(optval, scontext, scontext_len))
4132                 err = -EFAULT;
4133
4134 out_len:
4135         if (put_user(scontext_len, optlen))
4136                 err = -EFAULT;
4137         kfree(scontext);
4138         return err;
4139 }
4140
4141 static int selinux_socket_getpeersec_dgram(struct socket *sock, struct sk_buff *skb, u32 *secid)
4142 {
4143         u32 peer_secid = SECSID_NULL;
4144         u16 family;
4145
4146         if (skb && skb->protocol == htons(ETH_P_IP))
4147                 family = PF_INET;
4148         else if (skb && skb->protocol == htons(ETH_P_IPV6))
4149                 family = PF_INET6;
4150         else if (sock)
4151                 family = sock->sk->sk_family;
4152         else
4153                 goto out;
4154
4155         if (sock && family == PF_UNIX)
4156                 selinux_inode_getsecid(SOCK_INODE(sock), &peer_secid);
4157         else if (skb)
4158                 selinux_skb_peerlbl_sid(skb, family, &peer_secid);
4159
4160 out:
4161         *secid = peer_secid;
4162         if (peer_secid == SECSID_NULL)
4163                 return -EINVAL;
4164         return 0;
4165 }
4166
4167 static int selinux_sk_alloc_security(struct sock *sk, int family, gfp_t priority)
4168 {
4169         struct sk_security_struct *sksec;
4170
4171         sksec = kzalloc(sizeof(*sksec), priority);
4172         if (!sksec)
4173                 return -ENOMEM;
4174
4175         sksec->peer_sid = SECINITSID_UNLABELED;
4176         sksec->sid = SECINITSID_UNLABELED;
4177         selinux_netlbl_sk_security_reset(sksec);
4178         sk->sk_security = sksec;
4179
4180         return 0;
4181 }
4182
4183 static void selinux_sk_free_security(struct sock *sk)
4184 {
4185         struct sk_security_struct *sksec = sk->sk_security;
4186
4187         sk->sk_security = NULL;
4188         selinux_netlbl_sk_security_free(sksec);
4189         kfree(sksec);
4190 }
4191
4192 static void selinux_sk_clone_security(const struct sock *sk, struct sock *newsk)
4193 {
4194         struct sk_security_struct *sksec = sk->sk_security;
4195         struct sk_security_struct *newsksec = newsk->sk_security;
4196
4197         newsksec->sid = sksec->sid;
4198         newsksec->peer_sid = sksec->peer_sid;
4199         newsksec->sclass = sksec->sclass;
4200
4201         selinux_netlbl_sk_security_reset(newsksec);
4202 }
4203
4204 static void selinux_sk_getsecid(struct sock *sk, u32 *secid)
4205 {
4206         if (!sk)
4207                 *secid = SECINITSID_ANY_SOCKET;
4208         else {
4209                 struct sk_security_struct *sksec = sk->sk_security;
4210
4211                 *secid = sksec->sid;
4212         }
4213 }
4214
4215 static void selinux_sock_graft(struct sock *sk, struct socket *parent)
4216 {
4217         struct inode_security_struct *isec = SOCK_INODE(parent)->i_security;
4218         struct sk_security_struct *sksec = sk->sk_security;
4219
4220         if (sk->sk_family == PF_INET || sk->sk_family == PF_INET6 ||
4221             sk->sk_family == PF_UNIX)
4222                 isec->sid = sksec->sid;
4223         sksec->sclass = isec->sclass;
4224 }
4225
4226 static int selinux_inet_conn_request(struct sock *sk, struct sk_buff *skb,
4227                                      struct request_sock *req)
4228 {
4229         struct sk_security_struct *sksec = sk->sk_security;
4230         int err;
4231         u16 family = sk->sk_family;
4232         u32 newsid;
4233         u32 peersid;
4234
4235         /* handle mapped IPv4 packets arriving via IPv6 sockets */
4236         if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
4237                 family = PF_INET;
4238
4239         err = selinux_skb_peerlbl_sid(skb, family, &peersid);
4240         if (err)
4241                 return err;
4242         if (peersid == SECSID_NULL) {
4243                 req->secid = sksec->sid;
4244                 req->peer_secid = SECSID_NULL;
4245         } else {
4246                 err = security_sid_mls_copy(sksec->sid, peersid, &newsid);
4247                 if (err)
4248                         return err;
4249                 req->secid = newsid;
4250                 req->peer_secid = peersid;
4251         }
4252
4253         return selinux_netlbl_inet_conn_request(req, family);
4254 }
4255
4256 static void selinux_inet_csk_clone(struct sock *newsk,
4257                                    const struct request_sock *req)
4258 {
4259         struct sk_security_struct *newsksec = newsk->sk_security;
4260
4261         newsksec->sid = req->secid;
4262         newsksec->peer_sid = req->peer_secid;
4263         /* NOTE: Ideally, we should also get the isec->sid for the
4264            new socket in sync, but we don't have the isec available yet.
4265            So we will wait until sock_graft to do it, by which
4266            time it will have been created and available. */
4267
4268         /* We don't need to take any sort of lock here as we are the only
4269          * thread with access to newsksec */
4270         selinux_netlbl_inet_csk_clone(newsk, req->rsk_ops->family);
4271 }
4272
4273 static void selinux_inet_conn_established(struct sock *sk, struct sk_buff *skb)
4274 {
4275         u16 family = sk->sk_family;
4276         struct sk_security_struct *sksec = sk->sk_security;
4277
4278         /* handle mapped IPv4 packets arriving via IPv6 sockets */
4279         if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
4280                 family = PF_INET;
4281
4282         selinux_skb_peerlbl_sid(skb, family, &sksec->peer_sid);
4283 }
4284
4285 static int selinux_secmark_relabel_packet(u32 sid)
4286 {
4287         const struct task_security_struct *__tsec;
4288         u32 tsid;
4289
4290         __tsec = current_security();
4291         tsid = __tsec->sid;
4292
4293         return avc_has_perm(tsid, sid, SECCLASS_PACKET, PACKET__RELABELTO, NULL);
4294 }
4295
4296 static void selinux_secmark_refcount_inc(void)
4297 {
4298         atomic_inc(&selinux_secmark_refcount);
4299 }
4300
4301 static void selinux_secmark_refcount_dec(void)
4302 {
4303         atomic_dec(&selinux_secmark_refcount);
4304 }
4305
4306 static void selinux_req_classify_flow(const struct request_sock *req,
4307                                       struct flowi *fl)
4308 {
4309         fl->secid = req->secid;
4310 }
4311
4312 static int selinux_tun_dev_create(void)
4313 {
4314         u32 sid = current_sid();
4315
4316         /* we aren't taking into account the "sockcreate" SID since the socket
4317          * that is being created here is not a socket in the traditional sense,
4318          * instead it is a private sock, accessible only to the kernel, and
4319          * representing a wide range of network traffic spanning multiple
4320          * connections unlike traditional sockets - check the TUN driver to
4321          * get a better understanding of why this socket is special */
4322
4323         return avc_has_perm(sid, sid, SECCLASS_TUN_SOCKET, TUN_SOCKET__CREATE,
4324                             NULL);
4325 }
4326
4327 static void selinux_tun_dev_post_create(struct sock *sk)
4328 {
4329         struct sk_security_struct *sksec = sk->sk_security;
4330
4331         /* we don't currently perform any NetLabel based labeling here and it
4332          * isn't clear that we would want to do so anyway; while we could apply
4333          * labeling without the support of the TUN user the resulting labeled
4334          * traffic from the other end of the connection would almost certainly
4335          * cause confusion to the TUN user that had no idea network labeling
4336          * protocols were being used */
4337
4338         /* see the comments in selinux_tun_dev_create() about why we don't use
4339          * the sockcreate SID here */
4340
4341         sksec->sid = current_sid();
4342         sksec->sclass = SECCLASS_TUN_SOCKET;
4343 }
4344
4345 static int selinux_tun_dev_attach(struct sock *sk)
4346 {
4347         struct sk_security_struct *sksec = sk->sk_security;
4348         u32 sid = current_sid();
4349         int err;
4350
4351         err = avc_has_perm(sid, sksec->sid, SECCLASS_TUN_SOCKET,
4352                            TUN_SOCKET__RELABELFROM, NULL);
4353         if (err)
4354                 return err;
4355         err = avc_has_perm(sid, sid, SECCLASS_TUN_SOCKET,
4356                            TUN_SOCKET__RELABELTO, NULL);
4357         if (err)
4358                 return err;
4359
4360         sksec->sid = sid;
4361
4362         return 0;
4363 }
4364
4365 static int selinux_nlmsg_perm(struct sock *sk, struct sk_buff *skb)
4366 {
4367         int err = 0;
4368         u32 perm;
4369         struct nlmsghdr *nlh;
4370         struct sk_security_struct *sksec = sk->sk_security;
4371
4372         if (skb->len < NLMSG_SPACE(0)) {
4373                 err = -EINVAL;
4374                 goto out;
4375         }
4376         nlh = nlmsg_hdr(skb);
4377
4378         err = selinux_nlmsg_lookup(sksec->sclass, nlh->nlmsg_type, &perm);
4379         if (err) {
4380                 if (err == -EINVAL) {
4381                         audit_log(current->audit_context, GFP_KERNEL, AUDIT_SELINUX_ERR,
4382                                   "SELinux:  unrecognized netlink message"
4383                                   " type=%hu for sclass=%hu\n",
4384                                   nlh->nlmsg_type, sksec->sclass);
4385                         if (!selinux_enforcing || security_get_allow_unknown())
4386                                 err = 0;
4387                 }
4388
4389                 /* Ignore */
4390                 if (err == -ENOENT)
4391                         err = 0;
4392                 goto out;
4393         }
4394
4395         err = sock_has_perm(current, sk, perm);
4396 out:
4397         return err;
4398 }
4399
4400 #ifdef CONFIG_NETFILTER
4401
4402 static unsigned int selinux_ip_forward(struct sk_buff *skb, int ifindex,
4403                                        u16 family)
4404 {
4405         int err;
4406         char *addrp;
4407         u32 peer_sid;
4408         struct common_audit_data ad;
4409         u8 secmark_active;
4410         u8 netlbl_active;
4411         u8 peerlbl_active;
4412
4413         if (!selinux_policycap_netpeer)
4414                 return NF_ACCEPT;
4415
4416         secmark_active = selinux_secmark_enabled();
4417         netlbl_active = netlbl_enabled();
4418         peerlbl_active = netlbl_active || selinux_xfrm_enabled();
4419         if (!secmark_active && !peerlbl_active)
4420                 return NF_ACCEPT;
4421
4422         if (selinux_skb_peerlbl_sid(skb, family, &peer_sid) != 0)
4423                 return NF_DROP;
4424
4425         COMMON_AUDIT_DATA_INIT(&ad, NET);
4426         ad.u.net.netif = ifindex;
4427         ad.u.net.family = family;
4428         if (selinux_parse_skb(skb, &ad, &addrp, 1, NULL) != 0)
4429                 return NF_DROP;
4430
4431         if (peerlbl_active) {
4432                 err = selinux_inet_sys_rcv_skb(ifindex, addrp, family,
4433                                                peer_sid, &ad);
4434                 if (err) {
4435                         selinux_netlbl_err(skb, err, 1);
4436                         return NF_DROP;
4437                 }
4438         }
4439
4440         if (secmark_active)
4441                 if (avc_has_perm(peer_sid, skb->secmark,
4442                                  SECCLASS_PACKET, PACKET__FORWARD_IN, &ad))
4443                         return NF_DROP;
4444
4445         if (netlbl_active)
4446                 /* we do this in the FORWARD path and not the POST_ROUTING
4447                  * path because we want to make sure we apply the necessary
4448                  * labeling before IPsec is applied so we can leverage AH
4449                  * protection */
4450                 if (selinux_netlbl_skbuff_setsid(skb, family, peer_sid) != 0)
4451                         return NF_DROP;
4452
4453         return NF_ACCEPT;
4454 }
4455
4456 static unsigned int selinux_ipv4_forward(unsigned int hooknum,
4457                                          struct sk_buff *skb,
4458                                          const struct net_device *in,
4459                                          const struct net_device *out,
4460                                          int (*okfn)(struct sk_buff *))
4461 {
4462         return selinux_ip_forward(skb, in->ifindex, PF_INET);
4463 }
4464
4465 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
4466 static unsigned int selinux_ipv6_forward(unsigned int hooknum,
4467                                          struct sk_buff *skb,
4468                                          const struct net_device *in,
4469                                          const struct net_device *out,
4470                                          int (*okfn)(struct sk_buff *))
4471 {
4472         return selinux_ip_forward(skb, in->ifindex, PF_INET6);
4473 }
4474 #endif  /* IPV6 */
4475
4476 static unsigned int selinux_ip_output(struct sk_buff *skb,
4477                                       u16 family)
4478 {
4479         u32 sid;
4480
4481         if (!netlbl_enabled())
4482                 return NF_ACCEPT;
4483
4484         /* we do this in the LOCAL_OUT path and not the POST_ROUTING path
4485          * because we want to make sure we apply the necessary labeling
4486          * before IPsec is applied so we can leverage AH protection */
4487         if (skb->sk) {
4488                 struct sk_security_struct *sksec = skb->sk->sk_security;
4489                 sid = sksec->sid;
4490         } else
4491                 sid = SECINITSID_KERNEL;
4492         if (selinux_netlbl_skbuff_setsid(skb, family, sid) != 0)
4493                 return NF_DROP;
4494
4495         return NF_ACCEPT;
4496 }
4497
4498 static unsigned int selinux_ipv4_output(unsigned int hooknum,
4499                                         struct sk_buff *skb,
4500                                         const struct net_device *in,
4501                                         const struct net_device *out,
4502                                         int (*okfn)(struct sk_buff *))
4503 {
4504         return selinux_ip_output(skb, PF_INET);
4505 }
4506
4507 static unsigned int selinux_ip_postroute_compat(struct sk_buff *skb,
4508                                                 int ifindex,
4509                                                 u16 family)
4510 {
4511         struct sock *sk = skb->sk;
4512         struct sk_security_struct *sksec;
4513         struct common_audit_data ad;
4514         char *addrp;
4515         u8 proto;
4516
4517         if (sk == NULL)
4518                 return NF_ACCEPT;
4519         sksec = sk->sk_security;
4520
4521         COMMON_AUDIT_DATA_INIT(&ad, NET);
4522         ad.u.net.netif = ifindex;
4523         ad.u.net.family = family;
4524         if (selinux_parse_skb(skb, &ad, &addrp, 0, &proto))
4525                 return NF_DROP;
4526
4527         if (selinux_secmark_enabled())
4528                 if (avc_has_perm(sksec->sid, skb->secmark,
4529                                  SECCLASS_PACKET, PACKET__SEND, &ad))
4530                         return NF_DROP_ERR(-ECONNREFUSED);
4531
4532         if (selinux_policycap_netpeer)
4533                 if (selinux_xfrm_postroute_last(sksec->sid, skb, &ad, proto))
4534                         return NF_DROP_ERR(-ECONNREFUSED);
4535
4536         return NF_ACCEPT;
4537 }
4538
4539 static unsigned int selinux_ip_postroute(struct sk_buff *skb, int ifindex,
4540                                          u16 family)
4541 {
4542         u32 secmark_perm;
4543         u32 peer_sid;
4544         struct sock *sk;
4545         struct common_audit_data ad;
4546         char *addrp;
4547         u8 secmark_active;
4548         u8 peerlbl_active;
4549
4550         /* If any sort of compatibility mode is enabled then handoff processing
4551          * to the selinux_ip_postroute_compat() function to deal with the
4552          * special handling.  We do this in an attempt to keep this function
4553          * as fast and as clean as possible. */
4554         if (!selinux_policycap_netpeer)
4555                 return selinux_ip_postroute_compat(skb, ifindex, family);
4556 #ifdef CONFIG_XFRM
4557         /* If skb->dst->xfrm is non-NULL then the packet is undergoing an IPsec
4558          * packet transformation so allow the packet to pass without any checks
4559          * since we'll have another chance to perform access control checks
4560          * when the packet is on it's final way out.
4561          * NOTE: there appear to be some IPv6 multicast cases where skb->dst
4562          *       is NULL, in this case go ahead and apply access control. */
4563         if (skb_dst(skb) != NULL && skb_dst(skb)->xfrm != NULL)
4564                 return NF_ACCEPT;
4565 #endif
4566         secmark_active = selinux_secmark_enabled();
4567         peerlbl_active = netlbl_enabled() || selinux_xfrm_enabled();
4568         if (!secmark_active && !peerlbl_active)
4569                 return NF_ACCEPT;
4570
4571         /* if the packet is being forwarded then get the peer label from the
4572          * packet itself; otherwise check to see if it is from a local
4573          * application or the kernel, if from an application get the peer label
4574          * from the sending socket, otherwise use the kernel's sid */
4575         sk = skb->sk;
4576         if (sk == NULL) {
4577                 switch (family) {
4578                 case PF_INET:
4579                         if (IPCB(skb)->flags & IPSKB_FORWARDED)
4580                                 secmark_perm = PACKET__FORWARD_OUT;
4581                         else
4582                                 secmark_perm = PACKET__SEND;
4583                         break;
4584                 case PF_INET6:
4585                         if (IP6CB(skb)->flags & IP6SKB_FORWARDED)
4586                                 secmark_perm = PACKET__FORWARD_OUT;
4587                         else
4588                                 secmark_perm = PACKET__SEND;
4589                         break;
4590                 default:
4591                         return NF_DROP_ERR(-ECONNREFUSED);
4592                 }
4593                 if (secmark_perm == PACKET__FORWARD_OUT) {
4594                         if (selinux_skb_peerlbl_sid(skb, family, &peer_sid))
4595                                 return NF_DROP;
4596                 } else
4597                         peer_sid = SECINITSID_KERNEL;
4598         } else {
4599                 struct sk_security_struct *sksec = sk->sk_security;
4600                 peer_sid = sksec->sid;
4601                 secmark_perm = PACKET__SEND;
4602         }
4603
4604         COMMON_AUDIT_DATA_INIT(&ad, NET);
4605         ad.u.net.netif = ifindex;
4606         ad.u.net.family = family;
4607         if (selinux_parse_skb(skb, &ad, &addrp, 0, NULL))
4608                 return NF_DROP;
4609
4610         if (secmark_active)
4611                 if (avc_has_perm(peer_sid, skb->secmark,
4612                                  SECCLASS_PACKET, secmark_perm, &ad))
4613                         return NF_DROP_ERR(-ECONNREFUSED);
4614
4615         if (peerlbl_active) {
4616                 u32 if_sid;
4617                 u32 node_sid;
4618
4619                 if (sel_netif_sid(ifindex, &if_sid))
4620                         return NF_DROP;
4621                 if (avc_has_perm(peer_sid, if_sid,
4622                                  SECCLASS_NETIF, NETIF__EGRESS, &ad))
4623                         return NF_DROP_ERR(-ECONNREFUSED);
4624
4625                 if (sel_netnode_sid(addrp, family, &node_sid))
4626                         return NF_DROP;
4627                 if (avc_has_perm(peer_sid, node_sid,
4628                                  SECCLASS_NODE, NODE__SENDTO, &ad))
4629                         return NF_DROP_ERR(-ECONNREFUSED);
4630         }
4631
4632         return NF_ACCEPT;
4633 }
4634
4635 static unsigned int selinux_ipv4_postroute(unsigned int hooknum,
4636                                            struct sk_buff *skb,
4637                                            const struct net_device *in,
4638                                            const struct net_device *out,
4639                                            int (*okfn)(struct sk_buff *))
4640 {
4641         return selinux_ip_postroute(skb, out->ifindex, PF_INET);
4642 }
4643
4644 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
4645 static unsigned int selinux_ipv6_postroute(unsigned int hooknum,
4646                                            struct sk_buff *skb,
4647                                            const struct net_device *in,
4648                                            const struct net_device *out,
4649                                            int (*okfn)(struct sk_buff *))
4650 {
4651         return selinux_ip_postroute(skb, out->ifindex, PF_INET6);
4652 }
4653 #endif  /* IPV6 */
4654
4655 #endif  /* CONFIG_NETFILTER */
4656
4657 static int selinux_netlink_send(struct sock *sk, struct sk_buff *skb)
4658 {
4659         int err;
4660
4661         err = cap_netlink_send(sk, skb);
4662         if (err)
4663                 return err;
4664
4665         return selinux_nlmsg_perm(sk, skb);
4666 }
4667
4668 static int selinux_netlink_recv(struct sk_buff *skb, int capability)
4669 {
4670         int err;
4671         struct common_audit_data ad;
4672
4673         err = cap_netlink_recv(skb, capability);
4674         if (err)
4675                 return err;
4676
4677         COMMON_AUDIT_DATA_INIT(&ad, CAP);
4678         ad.u.cap = capability;
4679
4680         return avc_has_perm(NETLINK_CB(skb).sid, NETLINK_CB(skb).sid,
4681                             SECCLASS_CAPABILITY, CAP_TO_MASK(capability), &ad);
4682 }
4683
4684 static int ipc_alloc_security(struct task_struct *task,
4685                               struct kern_ipc_perm *perm,
4686                               u16 sclass)
4687 {
4688         struct ipc_security_struct *isec;
4689         u32 sid;
4690
4691         isec = kzalloc(sizeof(struct ipc_security_struct), GFP_KERNEL);
4692         if (!isec)
4693                 return -ENOMEM;
4694
4695         sid = task_sid(task);
4696         isec->sclass = sclass;
4697         isec->sid = sid;
4698         perm->security = isec;
4699
4700         return 0;
4701 }
4702
4703 static void ipc_free_security(struct kern_ipc_perm *perm)
4704 {
4705         struct ipc_security_struct *isec = perm->security;
4706         perm->security = NULL;
4707         kfree(isec);
4708 }
4709
4710 static int msg_msg_alloc_security(struct msg_msg *msg)
4711 {
4712         struct msg_security_struct *msec;
4713
4714         msec = kzalloc(sizeof(struct msg_security_struct), GFP_KERNEL);
4715         if (!msec)
4716                 return -ENOMEM;
4717
4718         msec->sid = SECINITSID_UNLABELED;
4719         msg->security = msec;
4720
4721         return 0;
4722 }
4723
4724 static void msg_msg_free_security(struct msg_msg *msg)
4725 {
4726         struct msg_security_struct *msec = msg->security;
4727
4728         msg->security = NULL;
4729         kfree(msec);
4730 }
4731
4732 static int ipc_has_perm(struct kern_ipc_perm *ipc_perms,
4733                         u32 perms)
4734 {
4735         struct ipc_security_struct *isec;
4736         struct common_audit_data ad;
4737         u32 sid = current_sid();
4738
4739         isec = ipc_perms->security;
4740
4741         COMMON_AUDIT_DATA_INIT(&ad, IPC);
4742         ad.u.ipc_id = ipc_perms->key;
4743
4744         return avc_has_perm(sid, isec->sid, isec->sclass, perms, &ad);
4745 }
4746
4747 static int selinux_msg_msg_alloc_security(struct msg_msg *msg)
4748 {
4749         return msg_msg_alloc_security(msg);
4750 }
4751
4752 static void selinux_msg_msg_free_security(struct msg_msg *msg)
4753 {
4754         msg_msg_free_security(msg);
4755 }
4756
4757 /* message queue security operations */
4758 static int selinux_msg_queue_alloc_security(struct msg_queue *msq)
4759 {
4760         struct ipc_security_struct *isec;
4761         struct common_audit_data ad;
4762         u32 sid = current_sid();
4763         int rc;
4764
4765         rc = ipc_alloc_security(current, &msq->q_perm, SECCLASS_MSGQ);
4766         if (rc)
4767                 return rc;
4768
4769         isec = msq->q_perm.security;
4770
4771         COMMON_AUDIT_DATA_INIT(&ad, IPC);
4772         ad.u.ipc_id = msq->q_perm.key;
4773
4774         rc = avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
4775                           MSGQ__CREATE, &ad);
4776         if (rc) {
4777                 ipc_free_security(&msq->q_perm);
4778                 return rc;
4779         }
4780         return 0;
4781 }
4782
4783 static void selinux_msg_queue_free_security(struct msg_queue *msq)
4784 {
4785         ipc_free_security(&msq->q_perm);
4786 }
4787
4788 static int selinux_msg_queue_associate(struct msg_queue *msq, int msqflg)
4789 {
4790         struct ipc_security_struct *isec;
4791         struct common_audit_data ad;
4792         u32 sid = current_sid();
4793
4794         isec = msq->q_perm.security;
4795
4796         COMMON_AUDIT_DATA_INIT(&ad, IPC);
4797         ad.u.ipc_id = msq->q_perm.key;
4798
4799         return avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
4800                             MSGQ__ASSOCIATE, &ad);
4801 }
4802
4803 static int selinux_msg_queue_msgctl(struct msg_queue *msq, int cmd)
4804 {
4805         int err;
4806         int perms;
4807
4808         switch (cmd) {
4809         case IPC_INFO:
4810         case MSG_INFO:
4811                 /* No specific object, just general system-wide information. */
4812                 return task_has_system(current, SYSTEM__IPC_INFO);
4813         case IPC_STAT:
4814         case MSG_STAT:
4815                 perms = MSGQ__GETATTR | MSGQ__ASSOCIATE;
4816                 break;
4817         case IPC_SET:
4818                 perms = MSGQ__SETATTR;
4819                 break;
4820         case IPC_RMID:
4821                 perms = MSGQ__DESTROY;
4822                 break;
4823         default:
4824                 return 0;
4825         }
4826
4827         err = ipc_has_perm(&msq->q_perm, perms);
4828         return err;
4829 }
4830
4831 static int selinux_msg_queue_msgsnd(struct msg_queue *msq, struct msg_msg *msg, int msqflg)
4832 {
4833         struct ipc_security_struct *isec;
4834         struct msg_security_struct *msec;
4835         struct common_audit_data ad;
4836         u32 sid = current_sid();
4837         int rc;
4838
4839         isec = msq->q_perm.security;
4840         msec = msg->security;
4841
4842         /*
4843          * First time through, need to assign label to the message
4844          */
4845         if (msec->sid == SECINITSID_UNLABELED) {
4846                 /*
4847                  * Compute new sid based on current process and
4848                  * message queue this message will be stored in
4849                  */
4850                 rc = security_transition_sid(sid, isec->sid, SECCLASS_MSG,
4851                                              &msec->sid);
4852                 if (rc)
4853                         return rc;
4854         }
4855
4856         COMMON_AUDIT_DATA_INIT(&ad, IPC);
4857         ad.u.ipc_id = msq->q_perm.key;
4858
4859         /* Can this process write to the queue? */
4860         rc = avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
4861                           MSGQ__WRITE, &ad);
4862         if (!rc)
4863                 /* Can this process send the message */
4864                 rc = avc_has_perm(sid, msec->sid, SECCLASS_MSG,
4865                                   MSG__SEND, &ad);
4866         if (!rc)
4867                 /* Can the message be put in the queue? */
4868                 rc = avc_has_perm(msec->sid, isec->sid, SECCLASS_MSGQ,
4869                                   MSGQ__ENQUEUE, &ad);
4870
4871         return rc;
4872 }
4873
4874 static int selinux_msg_queue_msgrcv(struct msg_queue *msq, struct msg_msg *msg,
4875                                     struct task_struct *target,
4876                                     long type, int mode)
4877 {
4878         struct ipc_security_struct *isec;
4879         struct msg_security_struct *msec;
4880         struct common_audit_data ad;
4881         u32 sid = task_sid(target);
4882         int rc;
4883
4884         isec = msq->q_perm.security;
4885         msec = msg->security;
4886
4887         COMMON_AUDIT_DATA_INIT(&ad, IPC);
4888         ad.u.ipc_id = msq->q_perm.key;
4889
4890         rc = avc_has_perm(sid, isec->sid,
4891                           SECCLASS_MSGQ, MSGQ__READ, &ad);
4892         if (!rc)
4893                 rc = avc_has_perm(sid, msec->sid,
4894                                   SECCLASS_MSG, MSG__RECEIVE, &ad);
4895         return rc;
4896 }
4897
4898 /* Shared Memory security operations */
4899 static int selinux_shm_alloc_security(struct shmid_kernel *shp)
4900 {
4901         struct ipc_security_struct *isec;
4902         struct common_audit_data ad;
4903         u32 sid = current_sid();
4904         int rc;
4905
4906         rc = ipc_alloc_security(current, &shp->shm_perm, SECCLASS_SHM);
4907         if (rc)
4908                 return rc;
4909
4910         isec = shp->shm_perm.security;
4911
4912         COMMON_AUDIT_DATA_INIT(&ad, IPC);
4913         ad.u.ipc_id = shp->shm_perm.key;
4914
4915         rc = avc_has_perm(sid, isec->sid, SECCLASS_SHM,
4916                           SHM__CREATE, &ad);
4917         if (rc) {
4918                 ipc_free_security(&shp->shm_perm);
4919                 return rc;
4920         }
4921         return 0;
4922 }
4923
4924 static void selinux_shm_free_security(struct shmid_kernel *shp)
4925 {
4926         ipc_free_security(&shp->shm_perm);
4927 }
4928
4929 static int selinux_shm_associate(struct shmid_kernel *shp, int shmflg)
4930 {
4931         struct ipc_security_struct *isec;
4932         struct common_audit_data ad;
4933         u32 sid = current_sid();
4934
4935         isec = shp->shm_perm.security;
4936
4937         COMMON_AUDIT_DATA_INIT(&ad, IPC);
4938         ad.u.ipc_id = shp->shm_perm.key;
4939
4940         return avc_has_perm(sid, isec->sid, SECCLASS_SHM,
4941                             SHM__ASSOCIATE, &ad);
4942 }
4943
4944 /* Note, at this point, shp is locked down */
4945 static int selinux_shm_shmctl(struct shmid_kernel *shp, int cmd)
4946 {
4947         int perms;
4948         int err;
4949
4950         switch (cmd) {
4951         case IPC_INFO:
4952         case SHM_INFO:
4953                 /* No specific object, just general system-wide information. */
4954                 return task_has_system(current, SYSTEM__IPC_INFO);
4955         case IPC_STAT:
4956         case SHM_STAT:
4957                 perms = SHM__GETATTR | SHM__ASSOCIATE;
4958                 break;
4959         case IPC_SET:
4960                 perms = SHM__SETATTR;
4961                 break;
4962         case SHM_LOCK:
4963         case SHM_UNLOCK:
4964                 perms = SHM__LOCK;
4965                 break;
4966         case IPC_RMID:
4967                 perms = SHM__DESTROY;
4968                 break;
4969         default:
4970                 return 0;
4971         }
4972
4973         err = ipc_has_perm(&shp->shm_perm, perms);
4974         return err;
4975 }
4976
4977 static int selinux_shm_shmat(struct shmid_kernel *shp,
4978                              char __user *shmaddr, int shmflg)
4979 {
4980         u32 perms;
4981
4982         if (shmflg & SHM_RDONLY)
4983                 perms = SHM__READ;
4984         else
4985                 perms = SHM__READ | SHM__WRITE;
4986
4987         return ipc_has_perm(&shp->shm_perm, perms);
4988 }
4989
4990 /* Semaphore security operations */
4991 static int selinux_sem_alloc_security(struct sem_array *sma)
4992 {
4993         struct ipc_security_struct *isec;
4994         struct common_audit_data ad;
4995         u32 sid = current_sid();
4996         int rc;
4997
4998         rc = ipc_alloc_security(current, &sma->sem_perm, SECCLASS_SEM);
4999         if (rc)
5000                 return rc;
5001
5002         isec = sma->sem_perm.security;
5003
5004         COMMON_AUDIT_DATA_INIT(&ad, IPC);
5005         ad.u.ipc_id = sma->sem_perm.key;
5006
5007         rc = avc_has_perm(sid, isec->sid, SECCLASS_SEM,
5008                           SEM__CREATE, &ad);
5009         if (rc) {
5010                 ipc_free_security(&sma->sem_perm);
5011                 return rc;
5012         }
5013         return 0;
5014 }
5015
5016 static void selinux_sem_free_security(struct sem_array *sma)
5017 {
5018         ipc_free_security(&sma->sem_perm);
5019 }
5020
5021 static int selinux_sem_associate(struct sem_array *sma, int semflg)
5022 {
5023         struct ipc_security_struct *isec;
5024         struct common_audit_data ad;
5025         u32 sid = current_sid();
5026
5027         isec = sma->sem_perm.security;
5028
5029         COMMON_AUDIT_DATA_INIT(&ad, IPC);
5030         ad.u.ipc_id = sma->sem_perm.key;
5031
5032         return avc_has_perm(sid, isec->sid, SECCLASS_SEM,
5033                             SEM__ASSOCIATE, &ad);
5034 }
5035
5036 /* Note, at this point, sma is locked down */
5037 static int selinux_sem_semctl(struct sem_array *sma, int cmd)
5038 {
5039         int err;
5040         u32 perms;
5041
5042         switch (cmd) {
5043         case IPC_INFO:
5044         case SEM_INFO:
5045                 /* No specific object, just general system-wide information. */
5046                 return task_has_system(current, SYSTEM__IPC_INFO);
5047         case GETPID:
5048         case GETNCNT:
5049         case GETZCNT:
5050                 perms = SEM__GETATTR;
5051                 break;
5052         case GETVAL:
5053         case GETALL:
5054                 perms = SEM__READ;
5055                 break;
5056         case SETVAL:
5057         case SETALL:
5058                 perms = SEM__WRITE;
5059                 break;
5060         case IPC_RMID:
5061                 perms = SEM__DESTROY;
5062                 break;
5063         case IPC_SET:
5064                 perms = SEM__SETATTR;
5065                 break;
5066         case IPC_STAT:
5067         case SEM_STAT:
5068                 perms = SEM__GETATTR | SEM__ASSOCIATE;
5069                 break;
5070         default:
5071                 return 0;
5072         }
5073
5074         err = ipc_has_perm(&sma->sem_perm, perms);
5075         return err;
5076 }
5077
5078 static int selinux_sem_semop(struct sem_array *sma,
5079                              struct sembuf *sops, unsigned nsops, int alter)
5080 {
5081         u32 perms;
5082
5083         if (alter)
5084                 perms = SEM__READ | SEM__WRITE;
5085         else
5086                 perms = SEM__READ;
5087
5088         return ipc_has_perm(&sma->sem_perm, perms);
5089 }
5090
5091 static int selinux_ipc_permission(struct kern_ipc_perm *ipcp, short flag)
5092 {
5093         u32 av = 0;
5094
5095         av = 0;
5096         if (flag & S_IRUGO)
5097                 av |= IPC__UNIX_READ;
5098         if (flag & S_IWUGO)
5099                 av |= IPC__UNIX_WRITE;
5100
5101         if (av == 0)
5102                 return 0;
5103
5104         return ipc_has_perm(ipcp, av);
5105 }
5106
5107 static void selinux_ipc_getsecid(struct kern_ipc_perm *ipcp, u32 *secid)
5108 {
5109         struct ipc_security_struct *isec = ipcp->security;
5110         *secid = isec->sid;
5111 }
5112
5113 static void selinux_d_instantiate(struct dentry *dentry, struct inode *inode)
5114 {
5115         if (inode)
5116                 inode_doinit_with_dentry(inode, dentry);
5117 }
5118
5119 static int selinux_getprocattr(struct task_struct *p,
5120                                char *name, char **value)
5121 {
5122         const struct task_security_struct *__tsec;
5123         u32 sid;
5124         int error;
5125         unsigned len;
5126
5127         if (current != p) {
5128                 error = current_has_perm(p, PROCESS__GETATTR);
5129                 if (error)
5130                         return error;
5131         }
5132
5133         rcu_read_lock();
5134         __tsec = __task_cred(p)->security;
5135
5136         if (!strcmp(name, "current"))
5137                 sid = __tsec->sid;
5138         else if (!strcmp(name, "prev"))
5139                 sid = __tsec->osid;
5140         else if (!strcmp(name, "exec"))
5141                 sid = __tsec->exec_sid;
5142         else if (!strcmp(name, "fscreate"))
5143                 sid = __tsec->create_sid;
5144         else if (!strcmp(name, "keycreate"))
5145                 sid = __tsec->keycreate_sid;
5146         else if (!strcmp(name, "sockcreate"))
5147                 sid = __tsec->sockcreate_sid;
5148         else
5149                 goto invalid;
5150         rcu_read_unlock();
5151
5152         if (!sid)
5153                 return 0;
5154
5155         error = security_sid_to_context(sid, value, &len);
5156         if (error)
5157                 return error;
5158         return len;
5159
5160 invalid:
5161         rcu_read_unlock();
5162         return -EINVAL;
5163 }
5164
5165 static int selinux_setprocattr(struct task_struct *p,
5166                                char *name, void *value, size_t size)
5167 {
5168         struct task_security_struct *tsec;
5169         struct task_struct *tracer;
5170         struct cred *new;
5171         u32 sid = 0, ptsid;
5172         int error;
5173         char *str = value;
5174
5175         if (current != p) {
5176                 /* SELinux only allows a process to change its own
5177                    security attributes. */
5178                 return -EACCES;
5179         }
5180
5181         /*
5182          * Basic control over ability to set these attributes at all.
5183          * current == p, but we'll pass them separately in case the
5184          * above restriction is ever removed.
5185          */
5186         if (!strcmp(name, "exec"))
5187                 error = current_has_perm(p, PROCESS__SETEXEC);
5188         else if (!strcmp(name, "fscreate"))
5189                 error = current_has_perm(p, PROCESS__SETFSCREATE);
5190         else if (!strcmp(name, "keycreate"))
5191                 error = current_has_perm(p, PROCESS__SETKEYCREATE);
5192         else if (!strcmp(name, "sockcreate"))
5193                 error = current_has_perm(p, PROCESS__SETSOCKCREATE);
5194         else if (!strcmp(name, "current"))
5195                 error = current_has_perm(p, PROCESS__SETCURRENT);
5196         else
5197                 error = -EINVAL;
5198         if (error)
5199                 return error;
5200
5201         /* Obtain a SID for the context, if one was specified. */
5202         if (size && str[1] && str[1] != '\n') {
5203                 if (str[size-1] == '\n') {
5204                         str[size-1] = 0;
5205                         size--;
5206                 }
5207                 error = security_context_to_sid(value, size, &sid);
5208                 if (error == -EINVAL && !strcmp(name, "fscreate")) {
5209                         if (!capable(CAP_MAC_ADMIN))
5210                                 return error;
5211                         error = security_context_to_sid_force(value, size,
5212                                                               &sid);
5213                 }
5214                 if (error)
5215                         return error;
5216         }
5217
5218         new = prepare_creds();
5219         if (!new)
5220                 return -ENOMEM;
5221
5222         /* Permission checking based on the specified context is
5223            performed during the actual operation (execve,
5224            open/mkdir/...), when we know the full context of the
5225            operation.  See selinux_bprm_set_creds for the execve
5226            checks and may_create for the file creation checks. The
5227            operation will then fail if the context is not permitted. */
5228         tsec = new->security;
5229         if (!strcmp(name, "exec")) {
5230                 tsec->exec_sid = sid;
5231         } else if (!strcmp(name, "fscreate")) {
5232                 tsec->create_sid = sid;
5233         } else if (!strcmp(name, "keycreate")) {
5234                 error = may_create_key(sid, p);
5235                 if (error)
5236                         goto abort_change;
5237                 tsec->keycreate_sid = sid;
5238         } else if (!strcmp(name, "sockcreate")) {
5239                 tsec->sockcreate_sid = sid;
5240         } else if (!strcmp(name, "current")) {
5241                 error = -EINVAL;
5242                 if (sid == 0)
5243                         goto abort_change;
5244
5245                 /* Only allow single threaded processes to change context */
5246                 error = -EPERM;
5247                 if (!current_is_single_threaded()) {
5248                         error = security_bounded_transition(tsec->sid, sid);
5249                         if (error)
5250                                 goto abort_change;
5251                 }
5252
5253                 /* Check permissions for the transition. */
5254                 error = avc_has_perm(tsec->sid, sid, SECCLASS_PROCESS,
5255                                      PROCESS__DYNTRANSITION, NULL);
5256                 if (error)
5257                         goto abort_change;
5258
5259                 /* Check for ptracing, and update the task SID if ok.
5260                    Otherwise, leave SID unchanged and fail. */
5261                 ptsid = 0;
5262                 task_lock(p);
5263                 tracer = tracehook_tracer_task(p);
5264                 if (tracer)
5265                         ptsid = task_sid(tracer);
5266                 task_unlock(p);
5267
5268                 if (tracer) {
5269                         error = avc_has_perm(ptsid, sid, SECCLASS_PROCESS,
5270                                              PROCESS__PTRACE, NULL);
5271                         if (error)
5272                                 goto abort_change;
5273                 }
5274
5275                 tsec->sid = sid;
5276         } else {
5277                 error = -EINVAL;
5278                 goto abort_change;
5279         }
5280
5281         commit_creds(new);
5282         return size;
5283
5284 abort_change:
5285         abort_creds(new);
5286         return error;
5287 }
5288
5289 static int selinux_secid_to_secctx(u32 secid, char **secdata, u32 *seclen)
5290 {
5291         return security_sid_to_context(secid, secdata, seclen);
5292 }
5293
5294 static int selinux_secctx_to_secid(const char *secdata, u32 seclen, u32 *secid)
5295 {
5296         return security_context_to_sid(secdata, seclen, secid);
5297 }
5298
5299 static void selinux_release_secctx(char *secdata, u32 seclen)
5300 {
5301         kfree(secdata);
5302 }
5303
5304 /*
5305  *      called with inode->i_mutex locked
5306  */
5307 static int selinux_inode_notifysecctx(struct inode *inode, void *ctx, u32 ctxlen)
5308 {
5309         return selinux_inode_setsecurity(inode, XATTR_SELINUX_SUFFIX, ctx, ctxlen, 0);
5310 }
5311
5312 /*
5313  *      called with inode->i_mutex locked
5314  */
5315 static int selinux_inode_setsecctx(struct dentry *dentry, void *ctx, u32 ctxlen)
5316 {
5317         return __vfs_setxattr_noperm(dentry, XATTR_NAME_SELINUX, ctx, ctxlen, 0);
5318 }
5319
5320 static int selinux_inode_getsecctx(struct inode *inode, void **ctx, u32 *ctxlen)
5321 {
5322         int len = 0;
5323         len = selinux_inode_getsecurity(inode, XATTR_SELINUX_SUFFIX,
5324                                                 ctx, true);
5325         if (len < 0)
5326                 return len;
5327         *ctxlen = len;
5328         return 0;
5329 }
5330 #ifdef CONFIG_KEYS
5331
5332 static int selinux_key_alloc(struct key *k, const struct cred *cred,
5333                              unsigned long flags)
5334 {
5335         const struct task_security_struct *tsec;
5336         struct key_security_struct *ksec;
5337
5338         ksec = kzalloc(sizeof(struct key_security_struct), GFP_KERNEL);
5339         if (!ksec)
5340                 return -ENOMEM;
5341
5342         tsec = cred->security;
5343         if (tsec->keycreate_sid)
5344                 ksec->sid = tsec->keycreate_sid;
5345         else
5346                 ksec->sid = tsec->sid;
5347
5348         k->security = ksec;
5349         return 0;
5350 }
5351
5352 static void selinux_key_free(struct key *k)
5353 {
5354         struct key_security_struct *ksec = k->security;
5355
5356         k->security = NULL;
5357         kfree(ksec);
5358 }
5359
5360 static int selinux_key_permission(key_ref_t key_ref,
5361                                   const struct cred *cred,
5362                                   key_perm_t perm)
5363 {
5364         struct key *key;
5365         struct key_security_struct *ksec;
5366         u32 sid;
5367
5368         /* if no specific permissions are requested, we skip the
5369            permission check. No serious, additional covert channels
5370            appear to be created. */
5371         if (perm == 0)
5372                 return 0;
5373
5374         sid = cred_sid(cred);
5375
5376         key = key_ref_to_ptr(key_ref);
5377         ksec = key->security;
5378
5379         return avc_has_perm(sid, ksec->sid, SECCLASS_KEY, perm, NULL);
5380 }
5381
5382 static int selinux_key_getsecurity(struct key *key, char **_buffer)
5383 {
5384         struct key_security_struct *ksec = key->security;
5385         char *context = NULL;
5386         unsigned len;
5387         int rc;
5388
5389         rc = security_sid_to_context(ksec->sid, &context, &len);
5390         if (!rc)
5391                 rc = len;
5392         *_buffer = context;
5393         return rc;
5394 }
5395
5396 #endif
5397
5398 static struct security_operations selinux_ops = {
5399         .name =                         "selinux",
5400
5401         .ptrace_access_check =          selinux_ptrace_access_check,
5402         .ptrace_traceme =               selinux_ptrace_traceme,
5403         .capget =                       selinux_capget,
5404         .capset =                       selinux_capset,
5405         .sysctl =                       selinux_sysctl,
5406         .capable =                      selinux_capable,
5407         .quotactl =                     selinux_quotactl,
5408         .quota_on =                     selinux_quota_on,
5409         .syslog =                       selinux_syslog,
5410         .vm_enough_memory =             selinux_vm_enough_memory,
5411
5412         .netlink_send =                 selinux_netlink_send,
5413         .netlink_recv =                 selinux_netlink_recv,
5414
5415         .bprm_set_creds =               selinux_bprm_set_creds,
5416         .bprm_committing_creds =        selinux_bprm_committing_creds,
5417         .bprm_committed_creds =         selinux_bprm_committed_creds,
5418         .bprm_secureexec =              selinux_bprm_secureexec,
5419
5420         .sb_alloc_security =            selinux_sb_alloc_security,
5421         .sb_free_security =             selinux_sb_free_security,
5422         .sb_copy_data =                 selinux_sb_copy_data,
5423         .sb_kern_mount =                selinux_sb_kern_mount,
5424         .sb_show_options =              selinux_sb_show_options,
5425         .sb_statfs =                    selinux_sb_statfs,
5426         .sb_mount =                     selinux_mount,
5427         .sb_umount =                    selinux_umount,
5428         .sb_set_mnt_opts =              selinux_set_mnt_opts,
5429         .sb_clone_mnt_opts =            selinux_sb_clone_mnt_opts,
5430         .sb_parse_opts_str =            selinux_parse_opts_str,
5431
5432
5433         .inode_alloc_security =         selinux_inode_alloc_security,
5434         .inode_free_security =          selinux_inode_free_security,
5435         .inode_init_security =          selinux_inode_init_security,
5436         .inode_create =                 selinux_inode_create,
5437         .inode_link =                   selinux_inode_link,
5438         .inode_unlink =                 selinux_inode_unlink,
5439         .inode_symlink =                selinux_inode_symlink,
5440         .inode_mkdir =                  selinux_inode_mkdir,
5441         .inode_rmdir =                  selinux_inode_rmdir,
5442         .inode_mknod =                  selinux_inode_mknod,
5443         .inode_rename =                 selinux_inode_rename,
5444         .inode_readlink =               selinux_inode_readlink,
5445         .inode_follow_link =            selinux_inode_follow_link,
5446         .inode_permission =             selinux_inode_permission,
5447         .inode_setattr =                selinux_inode_setattr,
5448         .inode_getattr =                selinux_inode_getattr,
5449         .inode_setxattr =               selinux_inode_setxattr,
5450         .inode_post_setxattr =          selinux_inode_post_setxattr,
5451         .inode_getxattr =               selinux_inode_getxattr,
5452         .inode_listxattr =              selinux_inode_listxattr,
5453         .inode_removexattr =            selinux_inode_removexattr,
5454         .inode_getsecurity =            selinux_inode_getsecurity,
5455         .inode_setsecurity =            selinux_inode_setsecurity,
5456         .inode_listsecurity =           selinux_inode_listsecurity,
5457         .inode_getsecid =               selinux_inode_getsecid,
5458
5459         .file_permission =              selinux_file_permission,
5460         .file_alloc_security =          selinux_file_alloc_security,
5461         .file_free_security =           selinux_file_free_security,
5462         .file_ioctl =                   selinux_file_ioctl,
5463         .file_mmap =                    selinux_file_mmap,
5464         .file_mprotect =                selinux_file_mprotect,
5465         .file_lock =                    selinux_file_lock,
5466         .file_fcntl =                   selinux_file_fcntl,
5467         .file_set_fowner =              selinux_file_set_fowner,
5468         .file_send_sigiotask =          selinux_file_send_sigiotask,
5469         .file_receive =                 selinux_file_receive,
5470
5471         .dentry_open =                  selinux_dentry_open,
5472
5473         .task_create =                  selinux_task_create,
5474         .cred_alloc_blank =             selinux_cred_alloc_blank,
5475         .cred_free =                    selinux_cred_free,
5476         .cred_prepare =                 selinux_cred_prepare,
5477         .cred_transfer =                selinux_cred_transfer,
5478         .kernel_act_as =                selinux_kernel_act_as,
5479         .kernel_create_files_as =       selinux_kernel_create_files_as,
5480         .kernel_module_request =        selinux_kernel_module_request,
5481         .task_setpgid =                 selinux_task_setpgid,
5482         .task_getpgid =                 selinux_task_getpgid,
5483         .task_getsid =                  selinux_task_getsid,
5484         .task_getsecid =                selinux_task_getsecid,
5485         .task_setnice =                 selinux_task_setnice,
5486         .task_setioprio =               selinux_task_setioprio,
5487         .task_getioprio =               selinux_task_getioprio,
5488         .task_setrlimit =               selinux_task_setrlimit,
5489         .task_setscheduler =            selinux_task_setscheduler,
5490         .task_getscheduler =            selinux_task_getscheduler,
5491         .task_movememory =              selinux_task_movememory,
5492         .task_kill =                    selinux_task_kill,
5493         .task_wait =                    selinux_task_wait,
5494         .task_to_inode =                selinux_task_to_inode,
5495
5496         .ipc_permission =               selinux_ipc_permission,
5497         .ipc_getsecid =                 selinux_ipc_getsecid,
5498
5499         .msg_msg_alloc_security =       selinux_msg_msg_alloc_security,
5500         .msg_msg_free_security =        selinux_msg_msg_free_security,
5501
5502         .msg_queue_alloc_security =     selinux_msg_queue_alloc_security,
5503         .msg_queue_free_security =      selinux_msg_queue_free_security,
5504         .msg_queue_associate =          selinux_msg_queue_associate,
5505         .msg_queue_msgctl =             selinux_msg_queue_msgctl,
5506         .msg_queue_msgsnd =             selinux_msg_queue_msgsnd,
5507         .msg_queue_msgrcv =             selinux_msg_queue_msgrcv,
5508
5509         .shm_alloc_security =           selinux_shm_alloc_security,
5510         .shm_free_security =            selinux_shm_free_security,
5511         .shm_associate =                selinux_shm_associate,
5512         .shm_shmctl =                   selinux_shm_shmctl,
5513         .shm_shmat =                    selinux_shm_shmat,
5514
5515         .sem_alloc_security =           selinux_sem_alloc_security,
5516         .sem_free_security =            selinux_sem_free_security,
5517         .sem_associate =                selinux_sem_associate,
5518         .sem_semctl =                   selinux_sem_semctl,
5519         .sem_semop =                    selinux_sem_semop,
5520
5521         .d_instantiate =                selinux_d_instantiate,
5522
5523         .getprocattr =                  selinux_getprocattr,
5524         .setprocattr =                  selinux_setprocattr,
5525
5526         .secid_to_secctx =              selinux_secid_to_secctx,
5527         .secctx_to_secid =              selinux_secctx_to_secid,
5528         .release_secctx =               selinux_release_secctx,
5529         .inode_notifysecctx =           selinux_inode_notifysecctx,
5530         .inode_setsecctx =              selinux_inode_setsecctx,
5531         .inode_getsecctx =              selinux_inode_getsecctx,
5532
5533         .unix_stream_connect =          selinux_socket_unix_stream_connect,
5534         .unix_may_send =                selinux_socket_unix_may_send,
5535
5536         .socket_create =                selinux_socket_create,
5537         .socket_post_create =           selinux_socket_post_create,
5538         .socket_bind =                  selinux_socket_bind,
5539         .socket_connect =               selinux_socket_connect,
5540         .socket_listen =                selinux_socket_listen,
5541         .socket_accept =                selinux_socket_accept,
5542         .socket_sendmsg =               selinux_socket_sendmsg,
5543         .socket_recvmsg =               selinux_socket_recvmsg,
5544         .socket_getsockname =           selinux_socket_getsockname,
5545         .socket_getpeername =           selinux_socket_getpeername,
5546         .socket_getsockopt =            selinux_socket_getsockopt,
5547         .socket_setsockopt =            selinux_socket_setsockopt,
5548         .socket_shutdown =              selinux_socket_shutdown,
5549         .socket_sock_rcv_skb =          selinux_socket_sock_rcv_skb,
5550         .socket_getpeersec_stream =     selinux_socket_getpeersec_stream,
5551         .socket_getpeersec_dgram =      selinux_socket_getpeersec_dgram,
5552         .sk_alloc_security =            selinux_sk_alloc_security,
5553         .sk_free_security =             selinux_sk_free_security,
5554         .sk_clone_security =            selinux_sk_clone_security,
5555         .sk_getsecid =                  selinux_sk_getsecid,
5556         .sock_graft =                   selinux_sock_graft,
5557         .inet_conn_request =            selinux_inet_conn_request,
5558         .inet_csk_clone =               selinux_inet_csk_clone,
5559         .inet_conn_established =        selinux_inet_conn_established,
5560         .secmark_relabel_packet =       selinux_secmark_relabel_packet,
5561         .secmark_refcount_inc =         selinux_secmark_refcount_inc,
5562         .secmark_refcount_dec =         selinux_secmark_refcount_dec,
5563         .req_classify_flow =            selinux_req_classify_flow,
5564         .tun_dev_create =               selinux_tun_dev_create,
5565         .tun_dev_post_create =          selinux_tun_dev_post_create,
5566         .tun_dev_attach =               selinux_tun_dev_attach,
5567
5568 #ifdef CONFIG_SECURITY_NETWORK_XFRM
5569         .xfrm_policy_alloc_security =   selinux_xfrm_policy_alloc,
5570         .xfrm_policy_clone_security =   selinux_xfrm_policy_clone,
5571         .xfrm_policy_free_security =    selinux_xfrm_policy_free,
5572         .xfrm_policy_delete_security =  selinux_xfrm_policy_delete,
5573         .xfrm_state_alloc_security =    selinux_xfrm_state_alloc,
5574         .xfrm_state_free_security =     selinux_xfrm_state_free,
5575         .xfrm_state_delete_security =   selinux_xfrm_state_delete,
5576         .xfrm_policy_lookup =           selinux_xfrm_policy_lookup,
5577         .xfrm_state_pol_flow_match =    selinux_xfrm_state_pol_flow_match,
5578         .xfrm_decode_session =          selinux_xfrm_decode_session,
5579 #endif
5580
5581 #ifdef CONFIG_KEYS
5582         .key_alloc =                    selinux_key_alloc,
5583         .key_free =                     selinux_key_free,
5584         .key_permission =               selinux_key_permission,
5585         .key_getsecurity =              selinux_key_getsecurity,
5586 #endif
5587
5588 #ifdef CONFIG_AUDIT
5589         .audit_rule_init =              selinux_audit_rule_init,
5590         .audit_rule_known =             selinux_audit_rule_known,
5591         .audit_rule_match =             selinux_audit_rule_match,
5592         .audit_rule_free =              selinux_audit_rule_free,
5593 #endif
5594 };
5595
5596 static __init int selinux_init(void)
5597 {
5598         if (!security_module_enable(&selinux_ops)) {
5599                 selinux_enabled = 0;
5600                 return 0;
5601         }
5602
5603         if (!selinux_enabled) {
5604                 printk(KERN_INFO "SELinux:  Disabled at boot.\n");
5605                 return 0;
5606         }
5607
5608         printk(KERN_INFO "SELinux:  Initializing.\n");
5609
5610         /* Set the security state for the initial task. */
5611         cred_init_security();
5612
5613         default_noexec = !(VM_DATA_DEFAULT_FLAGS & VM_EXEC);
5614
5615         sel_inode_cache = kmem_cache_create("selinux_inode_security",
5616                                             sizeof(struct inode_security_struct),
5617                                             0, SLAB_PANIC, NULL);
5618         avc_init();
5619
5620         if (register_security(&selinux_ops))
5621                 panic("SELinux: Unable to register with kernel.\n");
5622
5623         if (selinux_enforcing)
5624                 printk(KERN_DEBUG "SELinux:  Starting in enforcing mode\n");
5625         else
5626                 printk(KERN_DEBUG "SELinux:  Starting in permissive mode\n");
5627
5628         return 0;
5629 }
5630
5631 static void delayed_superblock_init(struct super_block *sb, void *unused)
5632 {
5633         superblock_doinit(sb, NULL);
5634 }
5635
5636 void selinux_complete_init(void)
5637 {
5638         printk(KERN_DEBUG "SELinux:  Completing initialization.\n");
5639
5640         /* Set up any superblocks initialized prior to the policy load. */
5641         printk(KERN_DEBUG "SELinux:  Setting up existing superblocks.\n");
5642         iterate_supers(delayed_superblock_init, NULL);
5643 }
5644
5645 /* SELinux requires early initialization in order to label
5646    all processes and objects when they are created. */
5647 security_initcall(selinux_init);
5648
5649 #if defined(CONFIG_NETFILTER)
5650
5651 static struct nf_hook_ops selinux_ipv4_ops[] = {
5652         {
5653                 .hook =         selinux_ipv4_postroute,
5654                 .owner =        THIS_MODULE,
5655                 .pf =           PF_INET,
5656                 .hooknum =      NF_INET_POST_ROUTING,
5657                 .priority =     NF_IP_PRI_SELINUX_LAST,
5658         },
5659         {
5660                 .hook =         selinux_ipv4_forward,
5661                 .owner =        THIS_MODULE,
5662                 .pf =           PF_INET,
5663                 .hooknum =      NF_INET_FORWARD,
5664                 .priority =     NF_IP_PRI_SELINUX_FIRST,
5665         },
5666         {
5667                 .hook =         selinux_ipv4_output,
5668                 .owner =        THIS_MODULE,
5669                 .pf =           PF_INET,
5670                 .hooknum =      NF_INET_LOCAL_OUT,
5671                 .priority =     NF_IP_PRI_SELINUX_FIRST,
5672         }
5673 };
5674
5675 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
5676
5677 static struct nf_hook_ops selinux_ipv6_ops[] = {
5678         {
5679                 .hook =         selinux_ipv6_postroute,
5680                 .owner =        THIS_MODULE,
5681                 .pf =           PF_INET6,
5682                 .hooknum =      NF_INET_POST_ROUTING,
5683                 .priority =     NF_IP6_PRI_SELINUX_LAST,
5684         },
5685         {
5686                 .hook =         selinux_ipv6_forward,
5687                 .owner =        THIS_MODULE,
5688                 .pf =           PF_INET6,
5689                 .hooknum =      NF_INET_FORWARD,
5690                 .priority =     NF_IP6_PRI_SELINUX_FIRST,
5691         }
5692 };
5693
5694 #endif  /* IPV6 */
5695
5696 static int __init selinux_nf_ip_init(void)
5697 {
5698         int err = 0;
5699
5700         if (!selinux_enabled)
5701                 goto out;
5702
5703         printk(KERN_DEBUG "SELinux:  Registering netfilter hooks\n");
5704
5705         err = nf_register_hooks(selinux_ipv4_ops, ARRAY_SIZE(selinux_ipv4_ops));
5706         if (err)
5707                 panic("SELinux: nf_register_hooks for IPv4: error %d\n", err);
5708
5709 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
5710         err = nf_register_hooks(selinux_ipv6_ops, ARRAY_SIZE(selinux_ipv6_ops));
5711         if (err)
5712                 panic("SELinux: nf_register_hooks for IPv6: error %d\n", err);
5713 #endif  /* IPV6 */
5714
5715 out:
5716         return err;
5717 }
5718
5719 __initcall(selinux_nf_ip_init);
5720
5721 #ifdef CONFIG_SECURITY_SELINUX_DISABLE
5722 static void selinux_nf_ip_exit(void)
5723 {
5724         printk(KERN_DEBUG "SELinux:  Unregistering netfilter hooks\n");
5725
5726         nf_unregister_hooks(selinux_ipv4_ops, ARRAY_SIZE(selinux_ipv4_ops));
5727 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
5728         nf_unregister_hooks(selinux_ipv6_ops, ARRAY_SIZE(selinux_ipv6_ops));
5729 #endif  /* IPV6 */
5730 }
5731 #endif
5732
5733 #else /* CONFIG_NETFILTER */
5734
5735 #ifdef CONFIG_SECURITY_SELINUX_DISABLE
5736 #define selinux_nf_ip_exit()
5737 #endif
5738
5739 #endif /* CONFIG_NETFILTER */
5740
5741 #ifdef CONFIG_SECURITY_SELINUX_DISABLE
5742 static int selinux_disabled;
5743
5744 int selinux_disable(void)
5745 {
5746         extern void exit_sel_fs(void);
5747
5748         if (ss_initialized) {
5749                 /* Not permitted after initial policy load. */
5750                 return -EINVAL;
5751         }
5752
5753         if (selinux_disabled) {
5754                 /* Only do this once. */
5755                 return -EINVAL;
5756         }
5757
5758         printk(KERN_INFO "SELinux:  Disabled at runtime.\n");
5759
5760         selinux_disabled = 1;
5761         selinux_enabled = 0;
5762
5763         reset_security_ops();
5764
5765         /* Try to destroy the avc node cache */
5766         avc_disable();
5767
5768         /* Unregister netfilter hooks. */
5769         selinux_nf_ip_exit();
5770
5771         /* Unregister selinuxfs. */
5772         exit_sel_fs();
5773
5774         return 0;
5775 }
5776 #endif