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, bool from_file)
1977 {
1978         int rc;
1979
1980         rc = cap_syslog(type, from_file);
1981         if (rc)
1982                 return rc;
1983
1984         switch (type) {
1985         case SYSLOG_ACTION_READ_ALL:    /* Read last kernel messages */
1986         case SYSLOG_ACTION_SIZE_BUFFER: /* Return size of the log buffer */
1987                 rc = task_has_system(current, SYSTEM__SYSLOG_READ);
1988                 break;
1989         case SYSLOG_ACTION_CONSOLE_OFF: /* Disable logging to console */
1990         case SYSLOG_ACTION_CONSOLE_ON:  /* Enable logging to console */
1991         /* Set level of messages printed to console */
1992         case SYSLOG_ACTION_CONSOLE_LEVEL:
1993                 rc = task_has_system(current, SYSTEM__SYSLOG_CONSOLE);
1994                 break;
1995         case SYSLOG_ACTION_CLOSE:       /* Close log */
1996         case SYSLOG_ACTION_OPEN:        /* Open log */
1997         case SYSLOG_ACTION_READ:        /* Read from log */
1998         case SYSLOG_ACTION_READ_CLEAR:  /* Read/clear last kernel messages */
1999         case SYSLOG_ACTION_CLEAR:       /* Clear ring buffer */
2000         default:
2001                 rc = task_has_system(current, SYSTEM__SYSLOG_MOD);
2002                 break;
2003         }
2004         return rc;
2005 }
2006
2007 /*
2008  * Check that a process has enough memory to allocate a new virtual
2009  * mapping. 0 means there is enough memory for the allocation to
2010  * succeed and -ENOMEM implies there is not.
2011  *
2012  * Do not audit the selinux permission check, as this is applied to all
2013  * processes that allocate mappings.
2014  */
2015 static int selinux_vm_enough_memory(struct mm_struct *mm, long pages)
2016 {
2017         int rc, cap_sys_admin = 0;
2018
2019         rc = selinux_capable(current, current_cred(), CAP_SYS_ADMIN,
2020                              SECURITY_CAP_NOAUDIT);
2021         if (rc == 0)
2022                 cap_sys_admin = 1;
2023
2024         return __vm_enough_memory(mm, pages, cap_sys_admin);
2025 }
2026
2027 /* binprm security operations */
2028
2029 static int selinux_bprm_set_creds(struct linux_binprm *bprm)
2030 {
2031         const struct task_security_struct *old_tsec;
2032         struct task_security_struct *new_tsec;
2033         struct inode_security_struct *isec;
2034         struct common_audit_data ad;
2035         struct inode *inode = bprm->file->f_path.dentry->d_inode;
2036         int rc;
2037
2038         rc = cap_bprm_set_creds(bprm);
2039         if (rc)
2040                 return rc;
2041
2042         /* SELinux context only depends on initial program or script and not
2043          * the script interpreter */
2044         if (bprm->cred_prepared)
2045                 return 0;
2046
2047         old_tsec = current_security();
2048         new_tsec = bprm->cred->security;
2049         isec = inode->i_security;
2050
2051         /* Default to the current task SID. */
2052         new_tsec->sid = old_tsec->sid;
2053         new_tsec->osid = old_tsec->sid;
2054
2055         /* Reset fs, key, and sock SIDs on execve. */
2056         new_tsec->create_sid = 0;
2057         new_tsec->keycreate_sid = 0;
2058         new_tsec->sockcreate_sid = 0;
2059
2060         if (old_tsec->exec_sid) {
2061                 new_tsec->sid = old_tsec->exec_sid;
2062                 /* Reset exec SID on execve. */
2063                 new_tsec->exec_sid = 0;
2064         } else {
2065                 /* Check for a default transition on this program. */
2066                 rc = security_transition_sid(old_tsec->sid, isec->sid,
2067                                              SECCLASS_PROCESS, &new_tsec->sid);
2068                 if (rc)
2069                         return rc;
2070         }
2071
2072         COMMON_AUDIT_DATA_INIT(&ad, FS);
2073         ad.u.fs.path = bprm->file->f_path;
2074
2075         if (bprm->file->f_path.mnt->mnt_flags & MNT_NOSUID)
2076                 new_tsec->sid = old_tsec->sid;
2077
2078         if (new_tsec->sid == old_tsec->sid) {
2079                 rc = avc_has_perm(old_tsec->sid, isec->sid,
2080                                   SECCLASS_FILE, FILE__EXECUTE_NO_TRANS, &ad);
2081                 if (rc)
2082                         return rc;
2083         } else {
2084                 /* Check permissions for the transition. */
2085                 rc = avc_has_perm(old_tsec->sid, new_tsec->sid,
2086                                   SECCLASS_PROCESS, PROCESS__TRANSITION, &ad);
2087                 if (rc)
2088                         return rc;
2089
2090                 rc = avc_has_perm(new_tsec->sid, isec->sid,
2091                                   SECCLASS_FILE, FILE__ENTRYPOINT, &ad);
2092                 if (rc)
2093                         return rc;
2094
2095                 /* Check for shared state */
2096                 if (bprm->unsafe & LSM_UNSAFE_SHARE) {
2097                         rc = avc_has_perm(old_tsec->sid, new_tsec->sid,
2098                                           SECCLASS_PROCESS, PROCESS__SHARE,
2099                                           NULL);
2100                         if (rc)
2101                                 return -EPERM;
2102                 }
2103
2104                 /* Make sure that anyone attempting to ptrace over a task that
2105                  * changes its SID has the appropriate permit */
2106                 if (bprm->unsafe &
2107                     (LSM_UNSAFE_PTRACE | LSM_UNSAFE_PTRACE_CAP)) {
2108                         struct task_struct *tracer;
2109                         struct task_security_struct *sec;
2110                         u32 ptsid = 0;
2111
2112                         rcu_read_lock();
2113                         tracer = tracehook_tracer_task(current);
2114                         if (likely(tracer != NULL)) {
2115                                 sec = __task_cred(tracer)->security;
2116                                 ptsid = sec->sid;
2117                         }
2118                         rcu_read_unlock();
2119
2120                         if (ptsid != 0) {
2121                                 rc = avc_has_perm(ptsid, new_tsec->sid,
2122                                                   SECCLASS_PROCESS,
2123                                                   PROCESS__PTRACE, NULL);
2124                                 if (rc)
2125                                         return -EPERM;
2126                         }
2127                 }
2128
2129                 /* Clear any possibly unsafe personality bits on exec: */
2130                 bprm->per_clear |= PER_CLEAR_ON_SETID;
2131         }
2132
2133         return 0;
2134 }
2135
2136 static int selinux_bprm_secureexec(struct linux_binprm *bprm)
2137 {
2138         const struct task_security_struct *tsec = current_security();
2139         u32 sid, osid;
2140         int atsecure = 0;
2141
2142         sid = tsec->sid;
2143         osid = tsec->osid;
2144
2145         if (osid != sid) {
2146                 /* Enable secure mode for SIDs transitions unless
2147                    the noatsecure permission is granted between
2148                    the two SIDs, i.e. ahp returns 0. */
2149                 atsecure = avc_has_perm(osid, sid,
2150                                         SECCLASS_PROCESS,
2151                                         PROCESS__NOATSECURE, NULL);
2152         }
2153
2154         return (atsecure || cap_bprm_secureexec(bprm));
2155 }
2156
2157 extern struct vfsmount *selinuxfs_mount;
2158 extern struct dentry *selinux_null;
2159
2160 /* Derived from fs/exec.c:flush_old_files. */
2161 static inline void flush_unauthorized_files(const struct cred *cred,
2162                                             struct files_struct *files)
2163 {
2164         struct common_audit_data ad;
2165         struct file *file, *devnull = NULL;
2166         struct tty_struct *tty;
2167         struct fdtable *fdt;
2168         long j = -1;
2169         int drop_tty = 0;
2170
2171         tty = get_current_tty();
2172         if (tty) {
2173                 spin_lock(&tty_files_lock);
2174                 if (!list_empty(&tty->tty_files)) {
2175                         struct tty_file_private *file_priv;
2176                         struct inode *inode;
2177
2178                         /* Revalidate access to controlling tty.
2179                            Use inode_has_perm on the tty inode directly rather
2180                            than using file_has_perm, as this particular open
2181                            file may belong to another process and we are only
2182                            interested in the inode-based check here. */
2183                         file_priv = list_first_entry(&tty->tty_files,
2184                                                 struct tty_file_private, list);
2185                         file = file_priv->file;
2186                         inode = file->f_path.dentry->d_inode;
2187                         if (inode_has_perm(cred, inode,
2188                                            FILE__READ | FILE__WRITE, NULL)) {
2189                                 drop_tty = 1;
2190                         }
2191                 }
2192                 spin_unlock(&tty_files_lock);
2193                 tty_kref_put(tty);
2194         }
2195         /* Reset controlling tty. */
2196         if (drop_tty)
2197                 no_tty();
2198
2199         /* Revalidate access to inherited open files. */
2200
2201         COMMON_AUDIT_DATA_INIT(&ad, FS);
2202
2203         spin_lock(&files->file_lock);
2204         for (;;) {
2205                 unsigned long set, i;
2206                 int fd;
2207
2208                 j++;
2209                 i = j * __NFDBITS;
2210                 fdt = files_fdtable(files);
2211                 if (i >= fdt->max_fds)
2212                         break;
2213                 set = fdt->open_fds->fds_bits[j];
2214                 if (!set)
2215                         continue;
2216                 spin_unlock(&files->file_lock);
2217                 for ( ; set ; i++, set >>= 1) {
2218                         if (set & 1) {
2219                                 file = fget(i);
2220                                 if (!file)
2221                                         continue;
2222                                 if (file_has_perm(cred,
2223                                                   file,
2224                                                   file_to_av(file))) {
2225                                         sys_close(i);
2226                                         fd = get_unused_fd();
2227                                         if (fd != i) {
2228                                                 if (fd >= 0)
2229                                                         put_unused_fd(fd);
2230                                                 fput(file);
2231                                                 continue;
2232                                         }
2233                                         if (devnull) {
2234                                                 get_file(devnull);
2235                                         } else {
2236                                                 devnull = dentry_open(
2237                                                         dget(selinux_null),
2238                                                         mntget(selinuxfs_mount),
2239                                                         O_RDWR, cred);
2240                                                 if (IS_ERR(devnull)) {
2241                                                         devnull = NULL;
2242                                                         put_unused_fd(fd);
2243                                                         fput(file);
2244                                                         continue;
2245                                                 }
2246                                         }
2247                                         fd_install(fd, devnull);
2248                                 }
2249                                 fput(file);
2250                         }
2251                 }
2252                 spin_lock(&files->file_lock);
2253
2254         }
2255         spin_unlock(&files->file_lock);
2256 }
2257
2258 /*
2259  * Prepare a process for imminent new credential changes due to exec
2260  */
2261 static void selinux_bprm_committing_creds(struct linux_binprm *bprm)
2262 {
2263         struct task_security_struct *new_tsec;
2264         struct rlimit *rlim, *initrlim;
2265         int rc, i;
2266
2267         new_tsec = bprm->cred->security;
2268         if (new_tsec->sid == new_tsec->osid)
2269                 return;
2270
2271         /* Close files for which the new task SID is not authorized. */
2272         flush_unauthorized_files(bprm->cred, current->files);
2273
2274         /* Always clear parent death signal on SID transitions. */
2275         current->pdeath_signal = 0;
2276
2277         /* Check whether the new SID can inherit resource limits from the old
2278          * SID.  If not, reset all soft limits to the lower of the current
2279          * task's hard limit and the init task's soft limit.
2280          *
2281          * Note that the setting of hard limits (even to lower them) can be
2282          * controlled by the setrlimit check.  The inclusion of the init task's
2283          * soft limit into the computation is to avoid resetting soft limits
2284          * higher than the default soft limit for cases where the default is
2285          * lower than the hard limit, e.g. RLIMIT_CORE or RLIMIT_STACK.
2286          */
2287         rc = avc_has_perm(new_tsec->osid, new_tsec->sid, SECCLASS_PROCESS,
2288                           PROCESS__RLIMITINH, NULL);
2289         if (rc) {
2290                 /* protect against do_prlimit() */
2291                 task_lock(current);
2292                 for (i = 0; i < RLIM_NLIMITS; i++) {
2293                         rlim = current->signal->rlim + i;
2294                         initrlim = init_task.signal->rlim + i;
2295                         rlim->rlim_cur = min(rlim->rlim_max, initrlim->rlim_cur);
2296                 }
2297                 task_unlock(current);
2298                 update_rlimit_cpu(current, rlimit(RLIMIT_CPU));
2299         }
2300 }
2301
2302 /*
2303  * Clean up the process immediately after the installation of new credentials
2304  * due to exec
2305  */
2306 static void selinux_bprm_committed_creds(struct linux_binprm *bprm)
2307 {
2308         const struct task_security_struct *tsec = current_security();
2309         struct itimerval itimer;
2310         u32 osid, sid;
2311         int rc, i;
2312
2313         osid = tsec->osid;
2314         sid = tsec->sid;
2315
2316         if (sid == osid)
2317                 return;
2318
2319         /* Check whether the new SID can inherit signal state from the old SID.
2320          * If not, clear itimers to avoid subsequent signal generation and
2321          * flush and unblock signals.
2322          *
2323          * This must occur _after_ the task SID has been updated so that any
2324          * kill done after the flush will be checked against the new SID.
2325          */
2326         rc = avc_has_perm(osid, sid, SECCLASS_PROCESS, PROCESS__SIGINH, NULL);
2327         if (rc) {
2328                 memset(&itimer, 0, sizeof itimer);
2329                 for (i = 0; i < 3; i++)
2330                         do_setitimer(i, &itimer, NULL);
2331                 spin_lock_irq(&current->sighand->siglock);
2332                 if (!(current->signal->flags & SIGNAL_GROUP_EXIT)) {
2333                         __flush_signals(current);
2334                         flush_signal_handlers(current, 1);
2335                         sigemptyset(&current->blocked);
2336                 }
2337                 spin_unlock_irq(&current->sighand->siglock);
2338         }
2339
2340         /* Wake up the parent if it is waiting so that it can recheck
2341          * wait permission to the new task SID. */
2342         read_lock(&tasklist_lock);
2343         __wake_up_parent(current, current->real_parent);
2344         read_unlock(&tasklist_lock);
2345 }
2346
2347 /* superblock security operations */
2348
2349 static int selinux_sb_alloc_security(struct super_block *sb)
2350 {
2351         return superblock_alloc_security(sb);
2352 }
2353
2354 static void selinux_sb_free_security(struct super_block *sb)
2355 {
2356         superblock_free_security(sb);
2357 }
2358
2359 static inline int match_prefix(char *prefix, int plen, char *option, int olen)
2360 {
2361         if (plen > olen)
2362                 return 0;
2363
2364         return !memcmp(prefix, option, plen);
2365 }
2366
2367 static inline int selinux_option(char *option, int len)
2368 {
2369         return (match_prefix(CONTEXT_STR, sizeof(CONTEXT_STR)-1, option, len) ||
2370                 match_prefix(FSCONTEXT_STR, sizeof(FSCONTEXT_STR)-1, option, len) ||
2371                 match_prefix(DEFCONTEXT_STR, sizeof(DEFCONTEXT_STR)-1, option, len) ||
2372                 match_prefix(ROOTCONTEXT_STR, sizeof(ROOTCONTEXT_STR)-1, option, len) ||
2373                 match_prefix(LABELSUPP_STR, sizeof(LABELSUPP_STR)-1, option, len));
2374 }
2375
2376 static inline void take_option(char **to, char *from, int *first, int len)
2377 {
2378         if (!*first) {
2379                 **to = ',';
2380                 *to += 1;
2381         } else
2382                 *first = 0;
2383         memcpy(*to, from, len);
2384         *to += len;
2385 }
2386
2387 static inline void take_selinux_option(char **to, char *from, int *first,
2388                                        int len)
2389 {
2390         int current_size = 0;
2391
2392         if (!*first) {
2393                 **to = '|';
2394                 *to += 1;
2395         } else
2396                 *first = 0;
2397
2398         while (current_size < len) {
2399                 if (*from != '"') {
2400                         **to = *from;
2401                         *to += 1;
2402                 }
2403                 from += 1;
2404                 current_size += 1;
2405         }
2406 }
2407
2408 static int selinux_sb_copy_data(char *orig, char *copy)
2409 {
2410         int fnosec, fsec, rc = 0;
2411         char *in_save, *in_curr, *in_end;
2412         char *sec_curr, *nosec_save, *nosec;
2413         int open_quote = 0;
2414
2415         in_curr = orig;
2416         sec_curr = copy;
2417
2418         nosec = (char *)get_zeroed_page(GFP_KERNEL);
2419         if (!nosec) {
2420                 rc = -ENOMEM;
2421                 goto out;
2422         }
2423
2424         nosec_save = nosec;
2425         fnosec = fsec = 1;
2426         in_save = in_end = orig;
2427
2428         do {
2429                 if (*in_end == '"')
2430                         open_quote = !open_quote;
2431                 if ((*in_end == ',' && open_quote == 0) ||
2432                                 *in_end == '\0') {
2433                         int len = in_end - in_curr;
2434
2435                         if (selinux_option(in_curr, len))
2436                                 take_selinux_option(&sec_curr, in_curr, &fsec, len);
2437                         else
2438                                 take_option(&nosec, in_curr, &fnosec, len);
2439
2440                         in_curr = in_end + 1;
2441                 }
2442         } while (*in_end++);
2443
2444         strcpy(in_save, nosec_save);
2445         free_page((unsigned long)nosec_save);
2446 out:
2447         return rc;
2448 }
2449
2450 static int selinux_sb_kern_mount(struct super_block *sb, int flags, void *data)
2451 {
2452         const struct cred *cred = current_cred();
2453         struct common_audit_data ad;
2454         int rc;
2455
2456         rc = superblock_doinit(sb, data);
2457         if (rc)
2458                 return rc;
2459
2460         /* Allow all mounts performed by the kernel */
2461         if (flags & MS_KERNMOUNT)
2462                 return 0;
2463
2464         COMMON_AUDIT_DATA_INIT(&ad, FS);
2465         ad.u.fs.path.dentry = sb->s_root;
2466         return superblock_has_perm(cred, sb, FILESYSTEM__MOUNT, &ad);
2467 }
2468
2469 static int selinux_sb_statfs(struct dentry *dentry)
2470 {
2471         const struct cred *cred = current_cred();
2472         struct common_audit_data ad;
2473
2474         COMMON_AUDIT_DATA_INIT(&ad, FS);
2475         ad.u.fs.path.dentry = dentry->d_sb->s_root;
2476         return superblock_has_perm(cred, dentry->d_sb, FILESYSTEM__GETATTR, &ad);
2477 }
2478
2479 static int selinux_mount(char *dev_name,
2480                          struct path *path,
2481                          char *type,
2482                          unsigned long flags,
2483                          void *data)
2484 {
2485         const struct cred *cred = current_cred();
2486
2487         if (flags & MS_REMOUNT)
2488                 return superblock_has_perm(cred, path->mnt->mnt_sb,
2489                                            FILESYSTEM__REMOUNT, NULL);
2490         else
2491                 return dentry_has_perm(cred, path->mnt, path->dentry,
2492                                        FILE__MOUNTON);
2493 }
2494
2495 static int selinux_umount(struct vfsmount *mnt, int flags)
2496 {
2497         const struct cred *cred = current_cred();
2498
2499         return superblock_has_perm(cred, mnt->mnt_sb,
2500                                    FILESYSTEM__UNMOUNT, NULL);
2501 }
2502
2503 /* inode security operations */
2504
2505 static int selinux_inode_alloc_security(struct inode *inode)
2506 {
2507         return inode_alloc_security(inode);
2508 }
2509
2510 static void selinux_inode_free_security(struct inode *inode)
2511 {
2512         inode_free_security(inode);
2513 }
2514
2515 static int selinux_inode_init_security(struct inode *inode, struct inode *dir,
2516                                        char **name, void **value,
2517                                        size_t *len)
2518 {
2519         const struct task_security_struct *tsec = current_security();
2520         struct inode_security_struct *dsec;
2521         struct superblock_security_struct *sbsec;
2522         u32 sid, newsid, clen;
2523         int rc;
2524         char *namep = NULL, *context;
2525
2526         dsec = dir->i_security;
2527         sbsec = dir->i_sb->s_security;
2528
2529         sid = tsec->sid;
2530         newsid = tsec->create_sid;
2531
2532         if (!newsid || !(sbsec->flags & SE_SBLABELSUPP)) {
2533                 rc = security_transition_sid(sid, dsec->sid,
2534                                              inode_mode_to_security_class(inode->i_mode),
2535                                              &newsid);
2536                 if (rc) {
2537                         printk(KERN_WARNING "%s:  "
2538                                "security_transition_sid failed, rc=%d (dev=%s "
2539                                "ino=%ld)\n",
2540                                __func__,
2541                                -rc, inode->i_sb->s_id, inode->i_ino);
2542                         return rc;
2543                 }
2544         }
2545
2546         /* Possibly defer initialization to selinux_complete_init. */
2547         if (sbsec->flags & SE_SBINITIALIZED) {
2548                 struct inode_security_struct *isec = inode->i_security;
2549                 isec->sclass = inode_mode_to_security_class(inode->i_mode);
2550                 isec->sid = newsid;
2551                 isec->initialized = 1;
2552         }
2553
2554         if (!ss_initialized || !(sbsec->flags & SE_SBLABELSUPP))
2555                 return -EOPNOTSUPP;
2556
2557         if (name) {
2558                 namep = kstrdup(XATTR_SELINUX_SUFFIX, GFP_NOFS);
2559                 if (!namep)
2560                         return -ENOMEM;
2561                 *name = namep;
2562         }
2563
2564         if (value && len) {
2565                 rc = security_sid_to_context_force(newsid, &context, &clen);
2566                 if (rc) {
2567                         kfree(namep);
2568                         return rc;
2569                 }
2570                 *value = context;
2571                 *len = clen;
2572         }
2573
2574         return 0;
2575 }
2576
2577 static int selinux_inode_create(struct inode *dir, struct dentry *dentry, int mask)
2578 {
2579         return may_create(dir, dentry, SECCLASS_FILE);
2580 }
2581
2582 static int selinux_inode_link(struct dentry *old_dentry, struct inode *dir, struct dentry *new_dentry)
2583 {
2584         return may_link(dir, old_dentry, MAY_LINK);
2585 }
2586
2587 static int selinux_inode_unlink(struct inode *dir, struct dentry *dentry)
2588 {
2589         return may_link(dir, dentry, MAY_UNLINK);
2590 }
2591
2592 static int selinux_inode_symlink(struct inode *dir, struct dentry *dentry, const char *name)
2593 {
2594         return may_create(dir, dentry, SECCLASS_LNK_FILE);
2595 }
2596
2597 static int selinux_inode_mkdir(struct inode *dir, struct dentry *dentry, int mask)
2598 {
2599         return may_create(dir, dentry, SECCLASS_DIR);
2600 }
2601
2602 static int selinux_inode_rmdir(struct inode *dir, struct dentry *dentry)
2603 {
2604         return may_link(dir, dentry, MAY_RMDIR);
2605 }
2606
2607 static int selinux_inode_mknod(struct inode *dir, struct dentry *dentry, int mode, dev_t dev)
2608 {
2609         return may_create(dir, dentry, inode_mode_to_security_class(mode));
2610 }
2611
2612 static int selinux_inode_rename(struct inode *old_inode, struct dentry *old_dentry,
2613                                 struct inode *new_inode, struct dentry *new_dentry)
2614 {
2615         return may_rename(old_inode, old_dentry, new_inode, new_dentry);
2616 }
2617
2618 static int selinux_inode_readlink(struct dentry *dentry)
2619 {
2620         const struct cred *cred = current_cred();
2621
2622         return dentry_has_perm(cred, NULL, dentry, FILE__READ);
2623 }
2624
2625 static int selinux_inode_follow_link(struct dentry *dentry, struct nameidata *nameidata)
2626 {
2627         const struct cred *cred = current_cred();
2628
2629         return dentry_has_perm(cred, NULL, dentry, FILE__READ);
2630 }
2631
2632 static int selinux_inode_permission(struct inode *inode, int mask)
2633 {
2634         const struct cred *cred = current_cred();
2635         struct common_audit_data ad;
2636         u32 perms;
2637         bool from_access;
2638
2639         from_access = mask & MAY_ACCESS;
2640         mask &= (MAY_READ|MAY_WRITE|MAY_EXEC|MAY_APPEND);
2641
2642         /* No permission to check.  Existence test. */
2643         if (!mask)
2644                 return 0;
2645
2646         COMMON_AUDIT_DATA_INIT(&ad, FS);
2647         ad.u.fs.inode = inode;
2648
2649         if (from_access)
2650                 ad.selinux_audit_data.auditdeny |= FILE__AUDIT_ACCESS;
2651
2652         perms = file_mask_to_av(inode->i_mode, mask);
2653
2654         return inode_has_perm(cred, inode, perms, &ad);
2655 }
2656
2657 static int selinux_inode_setattr(struct dentry *dentry, struct iattr *iattr)
2658 {
2659         const struct cred *cred = current_cred();
2660         unsigned int ia_valid = iattr->ia_valid;
2661
2662         /* ATTR_FORCE is just used for ATTR_KILL_S[UG]ID. */
2663         if (ia_valid & ATTR_FORCE) {
2664                 ia_valid &= ~(ATTR_KILL_SUID | ATTR_KILL_SGID | ATTR_MODE |
2665                               ATTR_FORCE);
2666                 if (!ia_valid)
2667                         return 0;
2668         }
2669
2670         if (ia_valid & (ATTR_MODE | ATTR_UID | ATTR_GID |
2671                         ATTR_ATIME_SET | ATTR_MTIME_SET | ATTR_TIMES_SET))
2672                 return dentry_has_perm(cred, NULL, dentry, FILE__SETATTR);
2673
2674         return dentry_has_perm(cred, NULL, dentry, FILE__WRITE);
2675 }
2676
2677 static int selinux_inode_getattr(struct vfsmount *mnt, struct dentry *dentry)
2678 {
2679         const struct cred *cred = current_cred();
2680
2681         return dentry_has_perm(cred, mnt, dentry, FILE__GETATTR);
2682 }
2683
2684 static int selinux_inode_setotherxattr(struct dentry *dentry, const char *name)
2685 {
2686         const struct cred *cred = current_cred();
2687
2688         if (!strncmp(name, XATTR_SECURITY_PREFIX,
2689                      sizeof XATTR_SECURITY_PREFIX - 1)) {
2690                 if (!strcmp(name, XATTR_NAME_CAPS)) {
2691                         if (!capable(CAP_SETFCAP))
2692                                 return -EPERM;
2693                 } else if (!capable(CAP_SYS_ADMIN)) {
2694                         /* A different attribute in the security namespace.
2695                            Restrict to administrator. */
2696                         return -EPERM;
2697                 }
2698         }
2699
2700         /* Not an attribute we recognize, so just check the
2701            ordinary setattr permission. */
2702         return dentry_has_perm(cred, NULL, dentry, FILE__SETATTR);
2703 }
2704
2705 static int selinux_inode_setxattr(struct dentry *dentry, const char *name,
2706                                   const void *value, size_t size, int flags)
2707 {
2708         struct inode *inode = dentry->d_inode;
2709         struct inode_security_struct *isec = inode->i_security;
2710         struct superblock_security_struct *sbsec;
2711         struct common_audit_data ad;
2712         u32 newsid, sid = current_sid();
2713         int rc = 0;
2714
2715         if (strcmp(name, XATTR_NAME_SELINUX))
2716                 return selinux_inode_setotherxattr(dentry, name);
2717
2718         sbsec = inode->i_sb->s_security;
2719         if (!(sbsec->flags & SE_SBLABELSUPP))
2720                 return -EOPNOTSUPP;
2721
2722         if (!is_owner_or_cap(inode))
2723                 return -EPERM;
2724
2725         COMMON_AUDIT_DATA_INIT(&ad, FS);
2726         ad.u.fs.path.dentry = dentry;
2727
2728         rc = avc_has_perm(sid, isec->sid, isec->sclass,
2729                           FILE__RELABELFROM, &ad);
2730         if (rc)
2731                 return rc;
2732
2733         rc = security_context_to_sid(value, size, &newsid);
2734         if (rc == -EINVAL) {
2735                 if (!capable(CAP_MAC_ADMIN))
2736                         return rc;
2737                 rc = security_context_to_sid_force(value, size, &newsid);
2738         }
2739         if (rc)
2740                 return rc;
2741
2742         rc = avc_has_perm(sid, newsid, isec->sclass,
2743                           FILE__RELABELTO, &ad);
2744         if (rc)
2745                 return rc;
2746
2747         rc = security_validate_transition(isec->sid, newsid, sid,
2748                                           isec->sclass);
2749         if (rc)
2750                 return rc;
2751
2752         return avc_has_perm(newsid,
2753                             sbsec->sid,
2754                             SECCLASS_FILESYSTEM,
2755                             FILESYSTEM__ASSOCIATE,
2756                             &ad);
2757 }
2758
2759 static void selinux_inode_post_setxattr(struct dentry *dentry, const char *name,
2760                                         const void *value, size_t size,
2761                                         int flags)
2762 {
2763         struct inode *inode = dentry->d_inode;
2764         struct inode_security_struct *isec = inode->i_security;
2765         u32 newsid;
2766         int rc;
2767
2768         if (strcmp(name, XATTR_NAME_SELINUX)) {
2769                 /* Not an attribute we recognize, so nothing to do. */
2770                 return;
2771         }
2772
2773         rc = security_context_to_sid_force(value, size, &newsid);
2774         if (rc) {
2775                 printk(KERN_ERR "SELinux:  unable to map context to SID"
2776                        "for (%s, %lu), rc=%d\n",
2777                        inode->i_sb->s_id, inode->i_ino, -rc);
2778                 return;
2779         }
2780
2781         isec->sid = newsid;
2782         return;
2783 }
2784
2785 static int selinux_inode_getxattr(struct dentry *dentry, const char *name)
2786 {
2787         const struct cred *cred = current_cred();
2788
2789         return dentry_has_perm(cred, NULL, dentry, FILE__GETATTR);
2790 }
2791
2792 static int selinux_inode_listxattr(struct dentry *dentry)
2793 {
2794         const struct cred *cred = current_cred();
2795
2796         return dentry_has_perm(cred, NULL, dentry, FILE__GETATTR);
2797 }
2798
2799 static int selinux_inode_removexattr(struct dentry *dentry, const char *name)
2800 {
2801         if (strcmp(name, XATTR_NAME_SELINUX))
2802                 return selinux_inode_setotherxattr(dentry, name);
2803
2804         /* No one is allowed to remove a SELinux security label.
2805            You can change the label, but all data must be labeled. */
2806         return -EACCES;
2807 }
2808
2809 /*
2810  * Copy the inode security context value to the user.
2811  *
2812  * Permission check is handled by selinux_inode_getxattr hook.
2813  */
2814 static int selinux_inode_getsecurity(const struct inode *inode, const char *name, void **buffer, bool alloc)
2815 {
2816         u32 size;
2817         int error;
2818         char *context = NULL;
2819         struct inode_security_struct *isec = inode->i_security;
2820
2821         if (strcmp(name, XATTR_SELINUX_SUFFIX))
2822                 return -EOPNOTSUPP;
2823
2824         /*
2825          * If the caller has CAP_MAC_ADMIN, then get the raw context
2826          * value even if it is not defined by current policy; otherwise,
2827          * use the in-core value under current policy.
2828          * Use the non-auditing forms of the permission checks since
2829          * getxattr may be called by unprivileged processes commonly
2830          * and lack of permission just means that we fall back to the
2831          * in-core context value, not a denial.
2832          */
2833         error = selinux_capable(current, current_cred(), CAP_MAC_ADMIN,
2834                                 SECURITY_CAP_NOAUDIT);
2835         if (!error)
2836                 error = security_sid_to_context_force(isec->sid, &context,
2837                                                       &size);
2838         else
2839                 error = security_sid_to_context(isec->sid, &context, &size);
2840         if (error)
2841                 return error;
2842         error = size;
2843         if (alloc) {
2844                 *buffer = context;
2845                 goto out_nofree;
2846         }
2847         kfree(context);
2848 out_nofree:
2849         return error;
2850 }
2851
2852 static int selinux_inode_setsecurity(struct inode *inode, const char *name,
2853                                      const void *value, size_t size, int flags)
2854 {
2855         struct inode_security_struct *isec = inode->i_security;
2856         u32 newsid;
2857         int rc;
2858
2859         if (strcmp(name, XATTR_SELINUX_SUFFIX))
2860                 return -EOPNOTSUPP;
2861
2862         if (!value || !size)
2863                 return -EACCES;
2864
2865         rc = security_context_to_sid((void *)value, size, &newsid);
2866         if (rc)
2867                 return rc;
2868
2869         isec->sid = newsid;
2870         isec->initialized = 1;
2871         return 0;
2872 }
2873
2874 static int selinux_inode_listsecurity(struct inode *inode, char *buffer, size_t buffer_size)
2875 {
2876         const int len = sizeof(XATTR_NAME_SELINUX);
2877         if (buffer && len <= buffer_size)
2878                 memcpy(buffer, XATTR_NAME_SELINUX, len);
2879         return len;
2880 }
2881
2882 static void selinux_inode_getsecid(const struct inode *inode, u32 *secid)
2883 {
2884         struct inode_security_struct *isec = inode->i_security;
2885         *secid = isec->sid;
2886 }
2887
2888 /* file security operations */
2889
2890 static int selinux_revalidate_file_permission(struct file *file, int mask)
2891 {
2892         const struct cred *cred = current_cred();
2893         struct inode *inode = file->f_path.dentry->d_inode;
2894
2895         /* file_mask_to_av won't add FILE__WRITE if MAY_APPEND is set */
2896         if ((file->f_flags & O_APPEND) && (mask & MAY_WRITE))
2897                 mask |= MAY_APPEND;
2898
2899         return file_has_perm(cred, file,
2900                              file_mask_to_av(inode->i_mode, mask));
2901 }
2902
2903 static int selinux_file_permission(struct file *file, int mask)
2904 {
2905         struct inode *inode = file->f_path.dentry->d_inode;
2906         struct file_security_struct *fsec = file->f_security;
2907         struct inode_security_struct *isec = inode->i_security;
2908         u32 sid = current_sid();
2909
2910         if (!mask)
2911                 /* No permission to check.  Existence test. */
2912                 return 0;
2913
2914         if (sid == fsec->sid && fsec->isid == isec->sid &&
2915             fsec->pseqno == avc_policy_seqno())
2916                 /* No change since dentry_open check. */
2917                 return 0;
2918
2919         return selinux_revalidate_file_permission(file, mask);
2920 }
2921
2922 static int selinux_file_alloc_security(struct file *file)
2923 {
2924         return file_alloc_security(file);
2925 }
2926
2927 static void selinux_file_free_security(struct file *file)
2928 {
2929         file_free_security(file);
2930 }
2931
2932 static int selinux_file_ioctl(struct file *file, unsigned int cmd,
2933                               unsigned long arg)
2934 {
2935         const struct cred *cred = current_cred();
2936         u32 av = 0;
2937
2938         if (_IOC_DIR(cmd) & _IOC_WRITE)
2939                 av |= FILE__WRITE;
2940         if (_IOC_DIR(cmd) & _IOC_READ)
2941                 av |= FILE__READ;
2942         if (!av)
2943                 av = FILE__IOCTL;
2944
2945         return file_has_perm(cred, file, av);
2946 }
2947
2948 static int default_noexec;
2949
2950 static int file_map_prot_check(struct file *file, unsigned long prot, int shared)
2951 {
2952         const struct cred *cred = current_cred();
2953         int rc = 0;
2954
2955         if (default_noexec &&
2956             (prot & PROT_EXEC) && (!file || (!shared && (prot & PROT_WRITE)))) {
2957                 /*
2958                  * We are making executable an anonymous mapping or a
2959                  * private file mapping that will also be writable.
2960                  * This has an additional check.
2961                  */
2962                 rc = cred_has_perm(cred, cred, PROCESS__EXECMEM);
2963                 if (rc)
2964                         goto error;
2965         }
2966
2967         if (file) {
2968                 /* read access is always possible with a mapping */
2969                 u32 av = FILE__READ;
2970
2971                 /* write access only matters if the mapping is shared */
2972                 if (shared && (prot & PROT_WRITE))
2973                         av |= FILE__WRITE;
2974
2975                 if (prot & PROT_EXEC)
2976                         av |= FILE__EXECUTE;
2977
2978                 return file_has_perm(cred, file, av);
2979         }
2980
2981 error:
2982         return rc;
2983 }
2984
2985 static int selinux_file_mmap(struct file *file, unsigned long reqprot,
2986                              unsigned long prot, unsigned long flags,
2987                              unsigned long addr, unsigned long addr_only)
2988 {
2989         int rc = 0;
2990         u32 sid = current_sid();
2991
2992         /*
2993          * notice that we are intentionally putting the SELinux check before
2994          * the secondary cap_file_mmap check.  This is such a likely attempt
2995          * at bad behaviour/exploit that we always want to get the AVC, even
2996          * if DAC would have also denied the operation.
2997          */
2998         if (addr < CONFIG_LSM_MMAP_MIN_ADDR) {
2999                 rc = avc_has_perm(sid, sid, SECCLASS_MEMPROTECT,
3000                                   MEMPROTECT__MMAP_ZERO, NULL);
3001                 if (rc)
3002                         return rc;
3003         }
3004
3005         /* do DAC check on address space usage */
3006         rc = cap_file_mmap(file, reqprot, prot, flags, addr, addr_only);
3007         if (rc || addr_only)
3008                 return rc;
3009
3010         if (selinux_checkreqprot)
3011                 prot = reqprot;
3012
3013         return file_map_prot_check(file, prot,
3014                                    (flags & MAP_TYPE) == MAP_SHARED);
3015 }
3016
3017 static int selinux_file_mprotect(struct vm_area_struct *vma,
3018                                  unsigned long reqprot,
3019                                  unsigned long prot)
3020 {
3021         const struct cred *cred = current_cred();
3022
3023         if (selinux_checkreqprot)
3024                 prot = reqprot;
3025
3026         if (default_noexec &&
3027             (prot & PROT_EXEC) && !(vma->vm_flags & VM_EXEC)) {
3028                 int rc = 0;
3029                 if (vma->vm_start >= vma->vm_mm->start_brk &&
3030                     vma->vm_end <= vma->vm_mm->brk) {
3031                         rc = cred_has_perm(cred, cred, PROCESS__EXECHEAP);
3032                 } else if (!vma->vm_file &&
3033                            vma->vm_start <= vma->vm_mm->start_stack &&
3034                            vma->vm_end >= vma->vm_mm->start_stack) {
3035                         rc = current_has_perm(current, PROCESS__EXECSTACK);
3036                 } else if (vma->vm_file && vma->anon_vma) {
3037                         /*
3038                          * We are making executable a file mapping that has
3039                          * had some COW done. Since pages might have been
3040                          * written, check ability to execute the possibly
3041                          * modified content.  This typically should only
3042                          * occur for text relocations.
3043                          */
3044                         rc = file_has_perm(cred, vma->vm_file, FILE__EXECMOD);
3045                 }
3046                 if (rc)
3047                         return rc;
3048         }
3049
3050         return file_map_prot_check(vma->vm_file, prot, vma->vm_flags&VM_SHARED);
3051 }
3052
3053 static int selinux_file_lock(struct file *file, unsigned int cmd)
3054 {
3055         const struct cred *cred = current_cred();
3056
3057         return file_has_perm(cred, file, FILE__LOCK);
3058 }
3059
3060 static int selinux_file_fcntl(struct file *file, unsigned int cmd,
3061                               unsigned long arg)
3062 {
3063         const struct cred *cred = current_cred();
3064         int err = 0;
3065
3066         switch (cmd) {
3067         case F_SETFL:
3068                 if (!file->f_path.dentry || !file->f_path.dentry->d_inode) {
3069                         err = -EINVAL;
3070                         break;
3071                 }
3072
3073                 if ((file->f_flags & O_APPEND) && !(arg & O_APPEND)) {
3074                         err = file_has_perm(cred, file, FILE__WRITE);
3075                         break;
3076                 }
3077                 /* fall through */
3078         case F_SETOWN:
3079         case F_SETSIG:
3080         case F_GETFL:
3081         case F_GETOWN:
3082         case F_GETSIG:
3083                 /* Just check FD__USE permission */
3084                 err = file_has_perm(cred, file, 0);
3085                 break;
3086         case F_GETLK:
3087         case F_SETLK:
3088         case F_SETLKW:
3089 #if BITS_PER_LONG == 32
3090         case F_GETLK64:
3091         case F_SETLK64:
3092         case F_SETLKW64:
3093 #endif
3094                 if (!file->f_path.dentry || !file->f_path.dentry->d_inode) {
3095                         err = -EINVAL;
3096                         break;
3097                 }
3098                 err = file_has_perm(cred, file, FILE__LOCK);
3099                 break;
3100         }
3101
3102         return err;
3103 }
3104
3105 static int selinux_file_set_fowner(struct file *file)
3106 {
3107         struct file_security_struct *fsec;
3108
3109         fsec = file->f_security;
3110         fsec->fown_sid = current_sid();
3111
3112         return 0;
3113 }
3114
3115 static int selinux_file_send_sigiotask(struct task_struct *tsk,
3116                                        struct fown_struct *fown, int signum)
3117 {
3118         struct file *file;
3119         u32 sid = task_sid(tsk);
3120         u32 perm;
3121         struct file_security_struct *fsec;
3122
3123         /* struct fown_struct is never outside the context of a struct file */
3124         file = container_of(fown, struct file, f_owner);
3125
3126         fsec = file->f_security;
3127
3128         if (!signum)
3129                 perm = signal_to_av(SIGIO); /* as per send_sigio_to_task */
3130         else
3131                 perm = signal_to_av(signum);
3132
3133         return avc_has_perm(fsec->fown_sid, sid,
3134                             SECCLASS_PROCESS, perm, NULL);
3135 }
3136
3137 static int selinux_file_receive(struct file *file)
3138 {
3139         const struct cred *cred = current_cred();
3140
3141         return file_has_perm(cred, file, file_to_av(file));
3142 }
3143
3144 static int selinux_dentry_open(struct file *file, const struct cred *cred)
3145 {
3146         struct file_security_struct *fsec;
3147         struct inode *inode;
3148         struct inode_security_struct *isec;
3149
3150         inode = file->f_path.dentry->d_inode;
3151         fsec = file->f_security;
3152         isec = inode->i_security;
3153         /*
3154          * Save inode label and policy sequence number
3155          * at open-time so that selinux_file_permission
3156          * can determine whether revalidation is necessary.
3157          * Task label is already saved in the file security
3158          * struct as its SID.
3159          */
3160         fsec->isid = isec->sid;
3161         fsec->pseqno = avc_policy_seqno();
3162         /*
3163          * Since the inode label or policy seqno may have changed
3164          * between the selinux_inode_permission check and the saving
3165          * of state above, recheck that access is still permitted.
3166          * Otherwise, access might never be revalidated against the
3167          * new inode label or new policy.
3168          * This check is not redundant - do not remove.
3169          */
3170         return inode_has_perm(cred, inode, open_file_to_av(file), NULL);
3171 }
3172
3173 /* task security operations */
3174
3175 static int selinux_task_create(unsigned long clone_flags)
3176 {
3177         return current_has_perm(current, PROCESS__FORK);
3178 }
3179
3180 /*
3181  * allocate the SELinux part of blank credentials
3182  */
3183 static int selinux_cred_alloc_blank(struct cred *cred, gfp_t gfp)
3184 {
3185         struct task_security_struct *tsec;
3186
3187         tsec = kzalloc(sizeof(struct task_security_struct), gfp);
3188         if (!tsec)
3189                 return -ENOMEM;
3190
3191         cred->security = tsec;
3192         return 0;
3193 }
3194
3195 /*
3196  * detach and free the LSM part of a set of credentials
3197  */
3198 static void selinux_cred_free(struct cred *cred)
3199 {
3200         struct task_security_struct *tsec = cred->security;
3201
3202         BUG_ON((unsigned long) cred->security < PAGE_SIZE);
3203         cred->security = (void *) 0x7UL;
3204         kfree(tsec);
3205 }
3206
3207 /*
3208  * prepare a new set of credentials for modification
3209  */
3210 static int selinux_cred_prepare(struct cred *new, const struct cred *old,
3211                                 gfp_t gfp)
3212 {
3213         const struct task_security_struct *old_tsec;
3214         struct task_security_struct *tsec;
3215
3216         old_tsec = old->security;
3217
3218         tsec = kmemdup(old_tsec, sizeof(struct task_security_struct), gfp);
3219         if (!tsec)
3220                 return -ENOMEM;
3221
3222         new->security = tsec;
3223         return 0;
3224 }
3225
3226 /*
3227  * transfer the SELinux data to a blank set of creds
3228  */
3229 static void selinux_cred_transfer(struct cred *new, const struct cred *old)
3230 {
3231         const struct task_security_struct *old_tsec = old->security;
3232         struct task_security_struct *tsec = new->security;
3233
3234         *tsec = *old_tsec;
3235 }
3236
3237 /*
3238  * set the security data for a kernel service
3239  * - all the creation contexts are set to unlabelled
3240  */
3241 static int selinux_kernel_act_as(struct cred *new, u32 secid)
3242 {
3243         struct task_security_struct *tsec = new->security;
3244         u32 sid = current_sid();
3245         int ret;
3246
3247         ret = avc_has_perm(sid, secid,
3248                            SECCLASS_KERNEL_SERVICE,
3249                            KERNEL_SERVICE__USE_AS_OVERRIDE,
3250                            NULL);
3251         if (ret == 0) {
3252                 tsec->sid = secid;
3253                 tsec->create_sid = 0;
3254                 tsec->keycreate_sid = 0;
3255                 tsec->sockcreate_sid = 0;
3256         }
3257         return ret;
3258 }
3259
3260 /*
3261  * set the file creation context in a security record to the same as the
3262  * objective context of the specified inode
3263  */
3264 static int selinux_kernel_create_files_as(struct cred *new, struct inode *inode)
3265 {
3266         struct inode_security_struct *isec = inode->i_security;
3267         struct task_security_struct *tsec = new->security;
3268         u32 sid = current_sid();
3269         int ret;
3270
3271         ret = avc_has_perm(sid, isec->sid,
3272                            SECCLASS_KERNEL_SERVICE,
3273                            KERNEL_SERVICE__CREATE_FILES_AS,
3274                            NULL);
3275
3276         if (ret == 0)
3277                 tsec->create_sid = isec->sid;
3278         return ret;
3279 }
3280
3281 static int selinux_kernel_module_request(char *kmod_name)
3282 {
3283         u32 sid;
3284         struct common_audit_data ad;
3285
3286         sid = task_sid(current);
3287
3288         COMMON_AUDIT_DATA_INIT(&ad, KMOD);
3289         ad.u.kmod_name = kmod_name;
3290
3291         return avc_has_perm(sid, SECINITSID_KERNEL, SECCLASS_SYSTEM,
3292                             SYSTEM__MODULE_REQUEST, &ad);
3293 }
3294
3295 static int selinux_task_setpgid(struct task_struct *p, pid_t pgid)
3296 {
3297         return current_has_perm(p, PROCESS__SETPGID);
3298 }
3299
3300 static int selinux_task_getpgid(struct task_struct *p)
3301 {
3302         return current_has_perm(p, PROCESS__GETPGID);
3303 }
3304
3305 static int selinux_task_getsid(struct task_struct *p)
3306 {
3307         return current_has_perm(p, PROCESS__GETSESSION);
3308 }
3309
3310 static void selinux_task_getsecid(struct task_struct *p, u32 *secid)
3311 {
3312         *secid = task_sid(p);
3313 }
3314
3315 static int selinux_task_setnice(struct task_struct *p, int nice)
3316 {
3317         int rc;
3318
3319         rc = cap_task_setnice(p, nice);
3320         if (rc)
3321                 return rc;
3322
3323         return current_has_perm(p, PROCESS__SETSCHED);
3324 }
3325
3326 static int selinux_task_setioprio(struct task_struct *p, int ioprio)
3327 {
3328         int rc;
3329
3330         rc = cap_task_setioprio(p, ioprio);
3331         if (rc)
3332                 return rc;
3333
3334         return current_has_perm(p, PROCESS__SETSCHED);
3335 }
3336
3337 static int selinux_task_getioprio(struct task_struct *p)
3338 {
3339         return current_has_perm(p, PROCESS__GETSCHED);
3340 }
3341
3342 static int selinux_task_setrlimit(struct task_struct *p, unsigned int resource,
3343                 struct rlimit *new_rlim)
3344 {
3345         struct rlimit *old_rlim = p->signal->rlim + resource;
3346
3347         /* Control the ability to change the hard limit (whether
3348            lowering or raising it), so that the hard limit can
3349            later be used as a safe reset point for the soft limit
3350            upon context transitions.  See selinux_bprm_committing_creds. */
3351         if (old_rlim->rlim_max != new_rlim->rlim_max)
3352                 return current_has_perm(p, PROCESS__SETRLIMIT);
3353
3354         return 0;
3355 }
3356
3357 static int selinux_task_setscheduler(struct task_struct *p)
3358 {
3359         int rc;
3360
3361         rc = cap_task_setscheduler(p);
3362         if (rc)
3363                 return rc;
3364
3365         return current_has_perm(p, PROCESS__SETSCHED);
3366 }
3367
3368 static int selinux_task_getscheduler(struct task_struct *p)
3369 {
3370         return current_has_perm(p, PROCESS__GETSCHED);
3371 }
3372
3373 static int selinux_task_movememory(struct task_struct *p)
3374 {
3375         return current_has_perm(p, PROCESS__SETSCHED);
3376 }
3377
3378 static int selinux_task_kill(struct task_struct *p, struct siginfo *info,
3379                                 int sig, u32 secid)
3380 {
3381         u32 perm;
3382         int rc;
3383
3384         if (!sig)
3385                 perm = PROCESS__SIGNULL; /* null signal; existence test */
3386         else
3387                 perm = signal_to_av(sig);
3388         if (secid)
3389                 rc = avc_has_perm(secid, task_sid(p),
3390                                   SECCLASS_PROCESS, perm, NULL);
3391         else
3392                 rc = current_has_perm(p, perm);
3393         return rc;
3394 }
3395
3396 static int selinux_task_wait(struct task_struct *p)
3397 {
3398         return task_has_perm(p, current, PROCESS__SIGCHLD);
3399 }
3400
3401 static void selinux_task_to_inode(struct task_struct *p,
3402                                   struct inode *inode)
3403 {
3404         struct inode_security_struct *isec = inode->i_security;
3405         u32 sid = task_sid(p);
3406
3407         isec->sid = sid;
3408         isec->initialized = 1;
3409 }
3410
3411 /* Returns error only if unable to parse addresses */
3412 static int selinux_parse_skb_ipv4(struct sk_buff *skb,
3413                         struct common_audit_data *ad, u8 *proto)
3414 {
3415         int offset, ihlen, ret = -EINVAL;
3416         struct iphdr _iph, *ih;
3417
3418         offset = skb_network_offset(skb);
3419         ih = skb_header_pointer(skb, offset, sizeof(_iph), &_iph);
3420         if (ih == NULL)
3421                 goto out;
3422
3423         ihlen = ih->ihl * 4;
3424         if (ihlen < sizeof(_iph))
3425                 goto out;
3426
3427         ad->u.net.v4info.saddr = ih->saddr;
3428         ad->u.net.v4info.daddr = ih->daddr;
3429         ret = 0;
3430
3431         if (proto)
3432                 *proto = ih->protocol;
3433
3434         switch (ih->protocol) {
3435         case IPPROTO_TCP: {
3436                 struct tcphdr _tcph, *th;
3437
3438                 if (ntohs(ih->frag_off) & IP_OFFSET)
3439                         break;
3440
3441                 offset += ihlen;
3442                 th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph);
3443                 if (th == NULL)
3444                         break;
3445
3446                 ad->u.net.sport = th->source;
3447                 ad->u.net.dport = th->dest;
3448                 break;
3449         }
3450
3451         case IPPROTO_UDP: {
3452                 struct udphdr _udph, *uh;
3453
3454                 if (ntohs(ih->frag_off) & IP_OFFSET)
3455                         break;
3456
3457                 offset += ihlen;
3458                 uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph);
3459                 if (uh == NULL)
3460                         break;
3461
3462                 ad->u.net.sport = uh->source;
3463                 ad->u.net.dport = uh->dest;
3464                 break;
3465         }
3466
3467         case IPPROTO_DCCP: {
3468                 struct dccp_hdr _dccph, *dh;
3469
3470                 if (ntohs(ih->frag_off) & IP_OFFSET)
3471                         break;
3472
3473                 offset += ihlen;
3474                 dh = skb_header_pointer(skb, offset, sizeof(_dccph), &_dccph);
3475                 if (dh == NULL)
3476                         break;
3477
3478                 ad->u.net.sport = dh->dccph_sport;
3479                 ad->u.net.dport = dh->dccph_dport;
3480                 break;
3481         }
3482
3483         default:
3484                 break;
3485         }
3486 out:
3487         return ret;
3488 }
3489
3490 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
3491
3492 /* Returns error only if unable to parse addresses */
3493 static int selinux_parse_skb_ipv6(struct sk_buff *skb,
3494                         struct common_audit_data *ad, u8 *proto)
3495 {
3496         u8 nexthdr;
3497         int ret = -EINVAL, offset;
3498         struct ipv6hdr _ipv6h, *ip6;
3499
3500         offset = skb_network_offset(skb);
3501         ip6 = skb_header_pointer(skb, offset, sizeof(_ipv6h), &_ipv6h);
3502         if (ip6 == NULL)
3503                 goto out;
3504
3505         ipv6_addr_copy(&ad->u.net.v6info.saddr, &ip6->saddr);
3506         ipv6_addr_copy(&ad->u.net.v6info.daddr, &ip6->daddr);
3507         ret = 0;
3508
3509         nexthdr = ip6->nexthdr;
3510         offset += sizeof(_ipv6h);
3511         offset = ipv6_skip_exthdr(skb, offset, &nexthdr);
3512         if (offset < 0)
3513                 goto out;
3514
3515         if (proto)
3516                 *proto = nexthdr;
3517
3518         switch (nexthdr) {
3519         case IPPROTO_TCP: {
3520                 struct tcphdr _tcph, *th;
3521
3522                 th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph);
3523                 if (th == NULL)
3524                         break;
3525
3526                 ad->u.net.sport = th->source;
3527                 ad->u.net.dport = th->dest;
3528                 break;
3529         }
3530
3531         case IPPROTO_UDP: {
3532                 struct udphdr _udph, *uh;
3533
3534                 uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph);
3535                 if (uh == NULL)
3536                         break;
3537
3538                 ad->u.net.sport = uh->source;
3539                 ad->u.net.dport = uh->dest;
3540                 break;
3541         }
3542
3543         case IPPROTO_DCCP: {
3544                 struct dccp_hdr _dccph, *dh;
3545
3546                 dh = skb_header_pointer(skb, offset, sizeof(_dccph), &_dccph);
3547                 if (dh == NULL)
3548                         break;
3549
3550                 ad->u.net.sport = dh->dccph_sport;
3551                 ad->u.net.dport = dh->dccph_dport;
3552                 break;
3553         }
3554
3555         /* includes fragments */
3556         default:
3557                 break;
3558         }
3559 out:
3560         return ret;
3561 }
3562
3563 #endif /* IPV6 */
3564
3565 static int selinux_parse_skb(struct sk_buff *skb, struct common_audit_data *ad,
3566                              char **_addrp, int src, u8 *proto)
3567 {
3568         char *addrp;
3569         int ret;
3570
3571         switch (ad->u.net.family) {
3572         case PF_INET:
3573                 ret = selinux_parse_skb_ipv4(skb, ad, proto);
3574                 if (ret)
3575                         goto parse_error;
3576                 addrp = (char *)(src ? &ad->u.net.v4info.saddr :
3577                                        &ad->u.net.v4info.daddr);
3578                 goto okay;
3579
3580 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
3581         case PF_INET6:
3582                 ret = selinux_parse_skb_ipv6(skb, ad, proto);
3583                 if (ret)
3584                         goto parse_error;
3585                 addrp = (char *)(src ? &ad->u.net.v6info.saddr :
3586                                        &ad->u.net.v6info.daddr);
3587                 goto okay;
3588 #endif  /* IPV6 */
3589         default:
3590                 addrp = NULL;
3591                 goto okay;
3592         }
3593
3594 parse_error:
3595         printk(KERN_WARNING
3596                "SELinux: failure in selinux_parse_skb(),"
3597                " unable to parse packet\n");
3598         return ret;
3599
3600 okay:
3601         if (_addrp)
3602                 *_addrp = addrp;
3603         return 0;
3604 }
3605
3606 /**
3607  * selinux_skb_peerlbl_sid - Determine the peer label of a packet
3608  * @skb: the packet
3609  * @family: protocol family
3610  * @sid: the packet's peer label SID
3611  *
3612  * Description:
3613  * Check the various different forms of network peer labeling and determine
3614  * the peer label/SID for the packet; most of the magic actually occurs in
3615  * the security server function security_net_peersid_cmp().  The function
3616  * returns zero if the value in @sid is valid (although it may be SECSID_NULL)
3617  * or -EACCES if @sid is invalid due to inconsistencies with the different
3618  * peer labels.
3619  *
3620  */
3621 static int selinux_skb_peerlbl_sid(struct sk_buff *skb, u16 family, u32 *sid)
3622 {
3623         int err;
3624         u32 xfrm_sid;
3625         u32 nlbl_sid;
3626         u32 nlbl_type;
3627
3628         selinux_skb_xfrm_sid(skb, &xfrm_sid);
3629         selinux_netlbl_skbuff_getsid(skb, family, &nlbl_type, &nlbl_sid);
3630
3631         err = security_net_peersid_resolve(nlbl_sid, nlbl_type, xfrm_sid, sid);
3632         if (unlikely(err)) {
3633                 printk(KERN_WARNING
3634                        "SELinux: failure in selinux_skb_peerlbl_sid(),"
3635                        " unable to determine packet's peer label\n");
3636                 return -EACCES;
3637         }
3638
3639         return 0;
3640 }
3641
3642 /* socket security operations */
3643
3644 static u32 socket_sockcreate_sid(const struct task_security_struct *tsec)
3645 {
3646         return tsec->sockcreate_sid ? : tsec->sid;
3647 }
3648
3649 static int sock_has_perm(struct task_struct *task, struct sock *sk, u32 perms)
3650 {
3651         struct sk_security_struct *sksec = sk->sk_security;
3652         struct common_audit_data ad;
3653         u32 tsid = task_sid(task);
3654
3655         if (sksec->sid == SECINITSID_KERNEL)
3656                 return 0;
3657
3658         COMMON_AUDIT_DATA_INIT(&ad, NET);
3659         ad.u.net.sk = sk;
3660
3661         return avc_has_perm(tsid, sksec->sid, sksec->sclass, perms, &ad);
3662 }
3663
3664 static int selinux_socket_create(int family, int type,
3665                                  int protocol, int kern)
3666 {
3667         const struct task_security_struct *tsec = current_security();
3668         u32 newsid;
3669         u16 secclass;
3670
3671         if (kern)
3672                 return 0;
3673
3674         newsid = socket_sockcreate_sid(tsec);
3675         secclass = socket_type_to_security_class(family, type, protocol);
3676         return avc_has_perm(tsec->sid, newsid, secclass, SOCKET__CREATE, NULL);
3677 }
3678
3679 static int selinux_socket_post_create(struct socket *sock, int family,
3680                                       int type, int protocol, int kern)
3681 {
3682         const struct task_security_struct *tsec = current_security();
3683         struct inode_security_struct *isec = SOCK_INODE(sock)->i_security;
3684         struct sk_security_struct *sksec;
3685         int err = 0;
3686
3687         if (kern)
3688                 isec->sid = SECINITSID_KERNEL;
3689         else
3690                 isec->sid = socket_sockcreate_sid(tsec);
3691
3692         isec->sclass = socket_type_to_security_class(family, type, protocol);
3693         isec->initialized = 1;
3694
3695         if (sock->sk) {
3696                 sksec = sock->sk->sk_security;
3697                 sksec->sid = isec->sid;
3698                 sksec->sclass = isec->sclass;
3699                 err = selinux_netlbl_socket_post_create(sock->sk, family);
3700         }
3701
3702         return err;
3703 }
3704
3705 /* Range of port numbers used to automatically bind.
3706    Need to determine whether we should perform a name_bind
3707    permission check between the socket and the port number. */
3708
3709 static int selinux_socket_bind(struct socket *sock, struct sockaddr *address, int addrlen)
3710 {
3711         struct sock *sk = sock->sk;
3712         u16 family;
3713         int err;
3714
3715         err = sock_has_perm(current, sk, SOCKET__BIND);
3716         if (err)
3717                 goto out;
3718
3719         /*
3720          * If PF_INET or PF_INET6, check name_bind permission for the port.
3721          * Multiple address binding for SCTP is not supported yet: we just
3722          * check the first address now.
3723          */
3724         family = sk->sk_family;
3725         if (family == PF_INET || family == PF_INET6) {
3726                 char *addrp;
3727                 struct sk_security_struct *sksec = sk->sk_security;
3728                 struct common_audit_data ad;
3729                 struct sockaddr_in *addr4 = NULL;
3730                 struct sockaddr_in6 *addr6 = NULL;
3731                 unsigned short snum;
3732                 u32 sid, node_perm;
3733
3734                 if (family == PF_INET) {
3735                         addr4 = (struct sockaddr_in *)address;
3736                         snum = ntohs(addr4->sin_port);
3737                         addrp = (char *)&addr4->sin_addr.s_addr;
3738                 } else {
3739                         addr6 = (struct sockaddr_in6 *)address;
3740                         snum = ntohs(addr6->sin6_port);
3741                         addrp = (char *)&addr6->sin6_addr.s6_addr;
3742                 }
3743
3744                 if (snum) {
3745                         int low, high;
3746
3747                         inet_get_local_port_range(&low, &high);
3748
3749                         if (snum < max(PROT_SOCK, low) || snum > high) {
3750                                 err = sel_netport_sid(sk->sk_protocol,
3751                                                       snum, &sid);
3752                                 if (err)
3753                                         goto out;
3754                                 COMMON_AUDIT_DATA_INIT(&ad, NET);
3755                                 ad.u.net.sport = htons(snum);
3756                                 ad.u.net.family = family;
3757                                 err = avc_has_perm(sksec->sid, sid,
3758                                                    sksec->sclass,
3759                                                    SOCKET__NAME_BIND, &ad);
3760                                 if (err)
3761                                         goto out;
3762                         }
3763                 }
3764
3765                 switch (sksec->sclass) {
3766                 case SECCLASS_TCP_SOCKET:
3767                         node_perm = TCP_SOCKET__NODE_BIND;
3768                         break;
3769
3770                 case SECCLASS_UDP_SOCKET:
3771                         node_perm = UDP_SOCKET__NODE_BIND;
3772                         break;
3773
3774                 case SECCLASS_DCCP_SOCKET:
3775                         node_perm = DCCP_SOCKET__NODE_BIND;
3776                         break;
3777
3778                 default:
3779                         node_perm = RAWIP_SOCKET__NODE_BIND;
3780                         break;
3781                 }
3782
3783                 err = sel_netnode_sid(addrp, family, &sid);
3784                 if (err)
3785                         goto out;
3786
3787                 COMMON_AUDIT_DATA_INIT(&ad, NET);
3788                 ad.u.net.sport = htons(snum);
3789                 ad.u.net.family = family;
3790
3791                 if (family == PF_INET)
3792                         ad.u.net.v4info.saddr = addr4->sin_addr.s_addr;
3793                 else
3794                         ipv6_addr_copy(&ad.u.net.v6info.saddr, &addr6->sin6_addr);
3795
3796                 err = avc_has_perm(sksec->sid, sid,
3797                                    sksec->sclass, node_perm, &ad);
3798                 if (err)
3799                         goto out;
3800         }
3801 out:
3802         return err;
3803 }
3804
3805 static int selinux_socket_connect(struct socket *sock, struct sockaddr *address, int addrlen)
3806 {
3807         struct sock *sk = sock->sk;
3808         struct sk_security_struct *sksec = sk->sk_security;
3809         int err;
3810
3811         err = sock_has_perm(current, sk, SOCKET__CONNECT);
3812         if (err)
3813                 return err;
3814
3815         /*
3816          * If a TCP or DCCP socket, check name_connect permission for the port.
3817          */
3818         if (sksec->sclass == SECCLASS_TCP_SOCKET ||
3819             sksec->sclass == SECCLASS_DCCP_SOCKET) {
3820                 struct common_audit_data ad;
3821                 struct sockaddr_in *addr4 = NULL;
3822                 struct sockaddr_in6 *addr6 = NULL;
3823                 unsigned short snum;
3824                 u32 sid, perm;
3825
3826                 if (sk->sk_family == PF_INET) {
3827                         addr4 = (struct sockaddr_in *)address;
3828                         if (addrlen < sizeof(struct sockaddr_in))
3829                                 return -EINVAL;
3830                         snum = ntohs(addr4->sin_port);
3831                 } else {
3832                         addr6 = (struct sockaddr_in6 *)address;
3833                         if (addrlen < SIN6_LEN_RFC2133)
3834                                 return -EINVAL;
3835                         snum = ntohs(addr6->sin6_port);
3836                 }
3837
3838                 err = sel_netport_sid(sk->sk_protocol, snum, &sid);
3839                 if (err)
3840                         goto out;
3841
3842                 perm = (sksec->sclass == SECCLASS_TCP_SOCKET) ?
3843                        TCP_SOCKET__NAME_CONNECT : DCCP_SOCKET__NAME_CONNECT;
3844
3845                 COMMON_AUDIT_DATA_INIT(&ad, NET);
3846                 ad.u.net.dport = htons(snum);
3847                 ad.u.net.family = sk->sk_family;
3848                 err = avc_has_perm(sksec->sid, sid, sksec->sclass, perm, &ad);
3849                 if (err)
3850                         goto out;
3851         }
3852
3853         err = selinux_netlbl_socket_connect(sk, address);
3854
3855 out:
3856         return err;
3857 }
3858
3859 static int selinux_socket_listen(struct socket *sock, int backlog)
3860 {
3861         return sock_has_perm(current, sock->sk, SOCKET__LISTEN);
3862 }
3863
3864 static int selinux_socket_accept(struct socket *sock, struct socket *newsock)
3865 {
3866         int err;
3867         struct inode_security_struct *isec;
3868         struct inode_security_struct *newisec;
3869
3870         err = sock_has_perm(current, sock->sk, SOCKET__ACCEPT);
3871         if (err)
3872                 return err;
3873
3874         newisec = SOCK_INODE(newsock)->i_security;
3875
3876         isec = SOCK_INODE(sock)->i_security;
3877         newisec->sclass = isec->sclass;
3878         newisec->sid = isec->sid;
3879         newisec->initialized = 1;
3880
3881         return 0;
3882 }
3883
3884 static int selinux_socket_sendmsg(struct socket *sock, struct msghdr *msg,
3885                                   int size)
3886 {
3887         return sock_has_perm(current, sock->sk, SOCKET__WRITE);
3888 }
3889
3890 static int selinux_socket_recvmsg(struct socket *sock, struct msghdr *msg,
3891                                   int size, int flags)
3892 {
3893         return sock_has_perm(current, sock->sk, SOCKET__READ);
3894 }
3895
3896 static int selinux_socket_getsockname(struct socket *sock)
3897 {
3898         return sock_has_perm(current, sock->sk, SOCKET__GETATTR);
3899 }
3900
3901 static int selinux_socket_getpeername(struct socket *sock)
3902 {
3903         return sock_has_perm(current, sock->sk, SOCKET__GETATTR);
3904 }
3905
3906 static int selinux_socket_setsockopt(struct socket *sock, int level, int optname)
3907 {
3908         int err;
3909
3910         err = sock_has_perm(current, sock->sk, SOCKET__SETOPT);
3911         if (err)
3912                 return err;
3913
3914         return selinux_netlbl_socket_setsockopt(sock, level, optname);
3915 }
3916
3917 static int selinux_socket_getsockopt(struct socket *sock, int level,
3918                                      int optname)
3919 {
3920         return sock_has_perm(current, sock->sk, SOCKET__GETOPT);
3921 }
3922
3923 static int selinux_socket_shutdown(struct socket *sock, int how)
3924 {
3925         return sock_has_perm(current, sock->sk, SOCKET__SHUTDOWN);
3926 }
3927
3928 static int selinux_socket_unix_stream_connect(struct socket *sock,
3929                                               struct socket *other,
3930                                               struct sock *newsk)
3931 {
3932         struct sk_security_struct *sksec_sock = sock->sk->sk_security;
3933         struct sk_security_struct *sksec_other = other->sk->sk_security;
3934         struct sk_security_struct *sksec_new = newsk->sk_security;
3935         struct common_audit_data ad;
3936         int err;
3937
3938         COMMON_AUDIT_DATA_INIT(&ad, NET);
3939         ad.u.net.sk = other->sk;
3940
3941         err = avc_has_perm(sksec_sock->sid, sksec_other->sid,
3942                            sksec_other->sclass,
3943                            UNIX_STREAM_SOCKET__CONNECTTO, &ad);
3944         if (err)
3945                 return err;
3946
3947         /* server child socket */
3948         sksec_new->peer_sid = sksec_sock->sid;
3949         err = security_sid_mls_copy(sksec_other->sid, sksec_sock->sid,
3950                                     &sksec_new->sid);
3951         if (err)
3952                 return err;
3953
3954         /* connecting socket */
3955         sksec_sock->peer_sid = sksec_new->sid;
3956
3957         return 0;
3958 }
3959
3960 static int selinux_socket_unix_may_send(struct socket *sock,
3961                                         struct socket *other)
3962 {
3963         struct sk_security_struct *ssec = sock->sk->sk_security;
3964         struct sk_security_struct *osec = other->sk->sk_security;
3965         struct common_audit_data ad;
3966
3967         COMMON_AUDIT_DATA_INIT(&ad, NET);
3968         ad.u.net.sk = other->sk;
3969
3970         return avc_has_perm(ssec->sid, osec->sid, osec->sclass, SOCKET__SENDTO,
3971                             &ad);
3972 }
3973
3974 static int selinux_inet_sys_rcv_skb(int ifindex, char *addrp, u16 family,
3975                                     u32 peer_sid,
3976                                     struct common_audit_data *ad)
3977 {
3978         int err;
3979         u32 if_sid;
3980         u32 node_sid;
3981
3982         err = sel_netif_sid(ifindex, &if_sid);
3983         if (err)
3984                 return err;
3985         err = avc_has_perm(peer_sid, if_sid,
3986                            SECCLASS_NETIF, NETIF__INGRESS, ad);
3987         if (err)
3988                 return err;
3989
3990         err = sel_netnode_sid(addrp, family, &node_sid);
3991         if (err)
3992                 return err;
3993         return avc_has_perm(peer_sid, node_sid,
3994                             SECCLASS_NODE, NODE__RECVFROM, ad);
3995 }
3996
3997 static int selinux_sock_rcv_skb_compat(struct sock *sk, struct sk_buff *skb,
3998                                        u16 family)
3999 {
4000         int err = 0;
4001         struct sk_security_struct *sksec = sk->sk_security;
4002         u32 peer_sid;
4003         u32 sk_sid = sksec->sid;
4004         struct common_audit_data ad;
4005         char *addrp;
4006
4007         COMMON_AUDIT_DATA_INIT(&ad, NET);
4008         ad.u.net.netif = skb->skb_iif;
4009         ad.u.net.family = family;
4010         err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL);
4011         if (err)
4012                 return err;
4013
4014         if (selinux_secmark_enabled()) {
4015                 err = avc_has_perm(sk_sid, skb->secmark, SECCLASS_PACKET,
4016                                    PACKET__RECV, &ad);
4017                 if (err)
4018                         return err;
4019         }
4020
4021         if (selinux_policycap_netpeer) {
4022                 err = selinux_skb_peerlbl_sid(skb, family, &peer_sid);
4023                 if (err)
4024                         return err;
4025                 err = avc_has_perm(sk_sid, peer_sid,
4026                                    SECCLASS_PEER, PEER__RECV, &ad);
4027                 if (err)
4028                         selinux_netlbl_err(skb, err, 0);
4029         } else {
4030                 err = selinux_netlbl_sock_rcv_skb(sksec, skb, family, &ad);
4031                 if (err)
4032                         return err;
4033                 err = selinux_xfrm_sock_rcv_skb(sksec->sid, skb, &ad);
4034         }
4035
4036         return err;
4037 }
4038
4039 static int selinux_socket_sock_rcv_skb(struct sock *sk, struct sk_buff *skb)
4040 {
4041         int err;
4042         struct sk_security_struct *sksec = sk->sk_security;
4043         u16 family = sk->sk_family;
4044         u32 sk_sid = sksec->sid;
4045         struct common_audit_data ad;
4046         char *addrp;
4047         u8 secmark_active;
4048         u8 peerlbl_active;
4049
4050         if (family != PF_INET && family != PF_INET6)
4051                 return 0;
4052
4053         /* Handle mapped IPv4 packets arriving via IPv6 sockets */
4054         if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
4055                 family = PF_INET;
4056
4057         /* If any sort of compatibility mode is enabled then handoff processing
4058          * to the selinux_sock_rcv_skb_compat() function to deal with the
4059          * special handling.  We do this in an attempt to keep this function
4060          * as fast and as clean as possible. */
4061         if (!selinux_policycap_netpeer)
4062                 return selinux_sock_rcv_skb_compat(sk, skb, family);
4063
4064         secmark_active = selinux_secmark_enabled();
4065         peerlbl_active = netlbl_enabled() || selinux_xfrm_enabled();
4066         if (!secmark_active && !peerlbl_active)
4067                 return 0;
4068
4069         COMMON_AUDIT_DATA_INIT(&ad, NET);
4070         ad.u.net.netif = skb->skb_iif;
4071         ad.u.net.family = family;
4072         err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL);
4073         if (err)
4074                 return err;
4075
4076         if (peerlbl_active) {
4077                 u32 peer_sid;
4078
4079                 err = selinux_skb_peerlbl_sid(skb, family, &peer_sid);
4080                 if (err)
4081                         return err;
4082                 err = selinux_inet_sys_rcv_skb(skb->skb_iif, addrp, family,
4083                                                peer_sid, &ad);
4084                 if (err) {
4085                         selinux_netlbl_err(skb, err, 0);
4086                         return err;
4087                 }
4088                 err = avc_has_perm(sk_sid, peer_sid, SECCLASS_PEER,
4089                                    PEER__RECV, &ad);
4090                 if (err)
4091                         selinux_netlbl_err(skb, err, 0);
4092         }
4093
4094         if (secmark_active) {
4095                 err = avc_has_perm(sk_sid, skb->secmark, SECCLASS_PACKET,
4096                                    PACKET__RECV, &ad);
4097                 if (err)
4098                         return err;
4099         }
4100
4101         return err;
4102 }
4103
4104 static int selinux_socket_getpeersec_stream(struct socket *sock, char __user *optval,
4105                                             int __user *optlen, unsigned len)
4106 {
4107         int err = 0;
4108         char *scontext;
4109         u32 scontext_len;
4110         struct sk_security_struct *sksec = sock->sk->sk_security;
4111         u32 peer_sid = SECSID_NULL;
4112
4113         if (sksec->sclass == SECCLASS_UNIX_STREAM_SOCKET ||
4114             sksec->sclass == SECCLASS_TCP_SOCKET)
4115                 peer_sid = sksec->peer_sid;
4116         if (peer_sid == SECSID_NULL)
4117                 return -ENOPROTOOPT;
4118
4119         err = security_sid_to_context(peer_sid, &scontext, &scontext_len);
4120         if (err)
4121                 return err;
4122
4123         if (scontext_len > len) {
4124                 err = -ERANGE;
4125                 goto out_len;
4126         }
4127
4128         if (copy_to_user(optval, scontext, scontext_len))
4129                 err = -EFAULT;
4130
4131 out_len:
4132         if (put_user(scontext_len, optlen))
4133                 err = -EFAULT;
4134         kfree(scontext);
4135         return err;
4136 }
4137
4138 static int selinux_socket_getpeersec_dgram(struct socket *sock, struct sk_buff *skb, u32 *secid)
4139 {
4140         u32 peer_secid = SECSID_NULL;
4141         u16 family;
4142
4143         if (skb && skb->protocol == htons(ETH_P_IP))
4144                 family = PF_INET;
4145         else if (skb && skb->protocol == htons(ETH_P_IPV6))
4146                 family = PF_INET6;
4147         else if (sock)
4148                 family = sock->sk->sk_family;
4149         else
4150                 goto out;
4151
4152         if (sock && family == PF_UNIX)
4153                 selinux_inode_getsecid(SOCK_INODE(sock), &peer_secid);
4154         else if (skb)
4155                 selinux_skb_peerlbl_sid(skb, family, &peer_secid);
4156
4157 out:
4158         *secid = peer_secid;
4159         if (peer_secid == SECSID_NULL)
4160                 return -EINVAL;
4161         return 0;
4162 }
4163
4164 static int selinux_sk_alloc_security(struct sock *sk, int family, gfp_t priority)
4165 {
4166         struct sk_security_struct *sksec;
4167
4168         sksec = kzalloc(sizeof(*sksec), priority);
4169         if (!sksec)
4170                 return -ENOMEM;
4171
4172         sksec->peer_sid = SECINITSID_UNLABELED;
4173         sksec->sid = SECINITSID_UNLABELED;
4174         selinux_netlbl_sk_security_reset(sksec);
4175         sk->sk_security = sksec;
4176
4177         return 0;
4178 }
4179
4180 static void selinux_sk_free_security(struct sock *sk)
4181 {
4182         struct sk_security_struct *sksec = sk->sk_security;
4183
4184         sk->sk_security = NULL;
4185         selinux_netlbl_sk_security_free(sksec);
4186         kfree(sksec);
4187 }
4188
4189 static void selinux_sk_clone_security(const struct sock *sk, struct sock *newsk)
4190 {
4191         struct sk_security_struct *sksec = sk->sk_security;
4192         struct sk_security_struct *newsksec = newsk->sk_security;
4193
4194         newsksec->sid = sksec->sid;
4195         newsksec->peer_sid = sksec->peer_sid;
4196         newsksec->sclass = sksec->sclass;
4197
4198         selinux_netlbl_sk_security_reset(newsksec);
4199 }
4200
4201 static void selinux_sk_getsecid(struct sock *sk, u32 *secid)
4202 {
4203         if (!sk)
4204                 *secid = SECINITSID_ANY_SOCKET;
4205         else {
4206                 struct sk_security_struct *sksec = sk->sk_security;
4207
4208                 *secid = sksec->sid;
4209         }
4210 }
4211
4212 static void selinux_sock_graft(struct sock *sk, struct socket *parent)
4213 {
4214         struct inode_security_struct *isec = SOCK_INODE(parent)->i_security;
4215         struct sk_security_struct *sksec = sk->sk_security;
4216
4217         if (sk->sk_family == PF_INET || sk->sk_family == PF_INET6 ||
4218             sk->sk_family == PF_UNIX)
4219                 isec->sid = sksec->sid;
4220         sksec->sclass = isec->sclass;
4221 }
4222
4223 static int selinux_inet_conn_request(struct sock *sk, struct sk_buff *skb,
4224                                      struct request_sock *req)
4225 {
4226         struct sk_security_struct *sksec = sk->sk_security;
4227         int err;
4228         u16 family = sk->sk_family;
4229         u32 newsid;
4230         u32 peersid;
4231
4232         /* handle mapped IPv4 packets arriving via IPv6 sockets */
4233         if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
4234                 family = PF_INET;
4235
4236         err = selinux_skb_peerlbl_sid(skb, family, &peersid);
4237         if (err)
4238                 return err;
4239         if (peersid == SECSID_NULL) {
4240                 req->secid = sksec->sid;
4241                 req->peer_secid = SECSID_NULL;
4242         } else {
4243                 err = security_sid_mls_copy(sksec->sid, peersid, &newsid);
4244                 if (err)
4245                         return err;
4246                 req->secid = newsid;
4247                 req->peer_secid = peersid;
4248         }
4249
4250         return selinux_netlbl_inet_conn_request(req, family);
4251 }
4252
4253 static void selinux_inet_csk_clone(struct sock *newsk,
4254                                    const struct request_sock *req)
4255 {
4256         struct sk_security_struct *newsksec = newsk->sk_security;
4257
4258         newsksec->sid = req->secid;
4259         newsksec->peer_sid = req->peer_secid;
4260         /* NOTE: Ideally, we should also get the isec->sid for the
4261            new socket in sync, but we don't have the isec available yet.
4262            So we will wait until sock_graft to do it, by which
4263            time it will have been created and available. */
4264
4265         /* We don't need to take any sort of lock here as we are the only
4266          * thread with access to newsksec */
4267         selinux_netlbl_inet_csk_clone(newsk, req->rsk_ops->family);
4268 }
4269
4270 static void selinux_inet_conn_established(struct sock *sk, struct sk_buff *skb)
4271 {
4272         u16 family = sk->sk_family;
4273         struct sk_security_struct *sksec = sk->sk_security;
4274
4275         /* handle mapped IPv4 packets arriving via IPv6 sockets */
4276         if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
4277                 family = PF_INET;
4278
4279         selinux_skb_peerlbl_sid(skb, family, &sksec->peer_sid);
4280 }
4281
4282 static int selinux_secmark_relabel_packet(u32 sid)
4283 {
4284         const struct task_security_struct *__tsec;
4285         u32 tsid;
4286
4287         __tsec = current_security();
4288         tsid = __tsec->sid;
4289
4290         return avc_has_perm(tsid, sid, SECCLASS_PACKET, PACKET__RELABELTO, NULL);
4291 }
4292
4293 static void selinux_secmark_refcount_inc(void)
4294 {
4295         atomic_inc(&selinux_secmark_refcount);
4296 }
4297
4298 static void selinux_secmark_refcount_dec(void)
4299 {
4300         atomic_dec(&selinux_secmark_refcount);
4301 }
4302
4303 static void selinux_req_classify_flow(const struct request_sock *req,
4304                                       struct flowi *fl)
4305 {
4306         fl->secid = req->secid;
4307 }
4308
4309 static int selinux_tun_dev_create(void)
4310 {
4311         u32 sid = current_sid();
4312
4313         /* we aren't taking into account the "sockcreate" SID since the socket
4314          * that is being created here is not a socket in the traditional sense,
4315          * instead it is a private sock, accessible only to the kernel, and
4316          * representing a wide range of network traffic spanning multiple
4317          * connections unlike traditional sockets - check the TUN driver to
4318          * get a better understanding of why this socket is special */
4319
4320         return avc_has_perm(sid, sid, SECCLASS_TUN_SOCKET, TUN_SOCKET__CREATE,
4321                             NULL);
4322 }
4323
4324 static void selinux_tun_dev_post_create(struct sock *sk)
4325 {
4326         struct sk_security_struct *sksec = sk->sk_security;
4327
4328         /* we don't currently perform any NetLabel based labeling here and it
4329          * isn't clear that we would want to do so anyway; while we could apply
4330          * labeling without the support of the TUN user the resulting labeled
4331          * traffic from the other end of the connection would almost certainly
4332          * cause confusion to the TUN user that had no idea network labeling
4333          * protocols were being used */
4334
4335         /* see the comments in selinux_tun_dev_create() about why we don't use
4336          * the sockcreate SID here */
4337
4338         sksec->sid = current_sid();
4339         sksec->sclass = SECCLASS_TUN_SOCKET;
4340 }
4341
4342 static int selinux_tun_dev_attach(struct sock *sk)
4343 {
4344         struct sk_security_struct *sksec = sk->sk_security;
4345         u32 sid = current_sid();
4346         int err;
4347
4348         err = avc_has_perm(sid, sksec->sid, SECCLASS_TUN_SOCKET,
4349                            TUN_SOCKET__RELABELFROM, NULL);
4350         if (err)
4351                 return err;
4352         err = avc_has_perm(sid, sid, SECCLASS_TUN_SOCKET,
4353                            TUN_SOCKET__RELABELTO, NULL);
4354         if (err)
4355                 return err;
4356
4357         sksec->sid = sid;
4358
4359         return 0;
4360 }
4361
4362 static int selinux_nlmsg_perm(struct sock *sk, struct sk_buff *skb)
4363 {
4364         int err = 0;
4365         u32 perm;
4366         struct nlmsghdr *nlh;
4367         struct sk_security_struct *sksec = sk->sk_security;
4368
4369         if (skb->len < NLMSG_SPACE(0)) {
4370                 err = -EINVAL;
4371                 goto out;
4372         }
4373         nlh = nlmsg_hdr(skb);
4374
4375         err = selinux_nlmsg_lookup(sksec->sclass, nlh->nlmsg_type, &perm);
4376         if (err) {
4377                 if (err == -EINVAL) {
4378                         audit_log(current->audit_context, GFP_KERNEL, AUDIT_SELINUX_ERR,
4379                                   "SELinux:  unrecognized netlink message"
4380                                   " type=%hu for sclass=%hu\n",
4381                                   nlh->nlmsg_type, sksec->sclass);
4382                         if (!selinux_enforcing || security_get_allow_unknown())
4383                                 err = 0;
4384                 }
4385
4386                 /* Ignore */
4387                 if (err == -ENOENT)
4388                         err = 0;
4389                 goto out;
4390         }
4391
4392         err = sock_has_perm(current, sk, perm);
4393 out:
4394         return err;
4395 }
4396
4397 #ifdef CONFIG_NETFILTER
4398
4399 static unsigned int selinux_ip_forward(struct sk_buff *skb, int ifindex,
4400                                        u16 family)
4401 {
4402         int err;
4403         char *addrp;
4404         u32 peer_sid;
4405         struct common_audit_data ad;
4406         u8 secmark_active;
4407         u8 netlbl_active;
4408         u8 peerlbl_active;
4409
4410         if (!selinux_policycap_netpeer)
4411                 return NF_ACCEPT;
4412
4413         secmark_active = selinux_secmark_enabled();
4414         netlbl_active = netlbl_enabled();
4415         peerlbl_active = netlbl_active || selinux_xfrm_enabled();
4416         if (!secmark_active && !peerlbl_active)
4417                 return NF_ACCEPT;
4418
4419         if (selinux_skb_peerlbl_sid(skb, family, &peer_sid) != 0)
4420                 return NF_DROP;
4421
4422         COMMON_AUDIT_DATA_INIT(&ad, NET);
4423         ad.u.net.netif = ifindex;
4424         ad.u.net.family = family;
4425         if (selinux_parse_skb(skb, &ad, &addrp, 1, NULL) != 0)
4426                 return NF_DROP;
4427
4428         if (peerlbl_active) {
4429                 err = selinux_inet_sys_rcv_skb(ifindex, addrp, family,
4430                                                peer_sid, &ad);
4431                 if (err) {
4432                         selinux_netlbl_err(skb, err, 1);
4433                         return NF_DROP;
4434                 }
4435         }
4436
4437         if (secmark_active)
4438                 if (avc_has_perm(peer_sid, skb->secmark,
4439                                  SECCLASS_PACKET, PACKET__FORWARD_IN, &ad))
4440                         return NF_DROP;
4441
4442         if (netlbl_active)
4443                 /* we do this in the FORWARD path and not the POST_ROUTING
4444                  * path because we want to make sure we apply the necessary
4445                  * labeling before IPsec is applied so we can leverage AH
4446                  * protection */
4447                 if (selinux_netlbl_skbuff_setsid(skb, family, peer_sid) != 0)
4448                         return NF_DROP;
4449
4450         return NF_ACCEPT;
4451 }
4452
4453 static unsigned int selinux_ipv4_forward(unsigned int hooknum,
4454                                          struct sk_buff *skb,
4455                                          const struct net_device *in,
4456                                          const struct net_device *out,
4457                                          int (*okfn)(struct sk_buff *))
4458 {
4459         return selinux_ip_forward(skb, in->ifindex, PF_INET);
4460 }
4461
4462 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
4463 static unsigned int selinux_ipv6_forward(unsigned int hooknum,
4464                                          struct sk_buff *skb,
4465                                          const struct net_device *in,
4466                                          const struct net_device *out,
4467                                          int (*okfn)(struct sk_buff *))
4468 {
4469         return selinux_ip_forward(skb, in->ifindex, PF_INET6);
4470 }
4471 #endif  /* IPV6 */
4472
4473 static unsigned int selinux_ip_output(struct sk_buff *skb,
4474                                       u16 family)
4475 {
4476         u32 sid;
4477
4478         if (!netlbl_enabled())
4479                 return NF_ACCEPT;
4480
4481         /* we do this in the LOCAL_OUT path and not the POST_ROUTING path
4482          * because we want to make sure we apply the necessary labeling
4483          * before IPsec is applied so we can leverage AH protection */
4484         if (skb->sk) {
4485                 struct sk_security_struct *sksec = skb->sk->sk_security;
4486                 sid = sksec->sid;
4487         } else
4488                 sid = SECINITSID_KERNEL;
4489         if (selinux_netlbl_skbuff_setsid(skb, family, sid) != 0)
4490                 return NF_DROP;
4491
4492         return NF_ACCEPT;
4493 }
4494
4495 static unsigned int selinux_ipv4_output(unsigned int hooknum,
4496                                         struct sk_buff *skb,
4497                                         const struct net_device *in,
4498                                         const struct net_device *out,
4499                                         int (*okfn)(struct sk_buff *))
4500 {
4501         return selinux_ip_output(skb, PF_INET);
4502 }
4503
4504 static unsigned int selinux_ip_postroute_compat(struct sk_buff *skb,
4505                                                 int ifindex,
4506                                                 u16 family)
4507 {
4508         struct sock *sk = skb->sk;
4509         struct sk_security_struct *sksec;
4510         struct common_audit_data ad;
4511         char *addrp;
4512         u8 proto;
4513
4514         if (sk == NULL)
4515                 return NF_ACCEPT;
4516         sksec = sk->sk_security;
4517
4518         COMMON_AUDIT_DATA_INIT(&ad, NET);
4519         ad.u.net.netif = ifindex;
4520         ad.u.net.family = family;
4521         if (selinux_parse_skb(skb, &ad, &addrp, 0, &proto))
4522                 return NF_DROP;
4523
4524         if (selinux_secmark_enabled())
4525                 if (avc_has_perm(sksec->sid, skb->secmark,
4526                                  SECCLASS_PACKET, PACKET__SEND, &ad))
4527                         return NF_DROP;
4528
4529         if (selinux_policycap_netpeer)
4530                 if (selinux_xfrm_postroute_last(sksec->sid, skb, &ad, proto))
4531                         return NF_DROP;
4532
4533         return NF_ACCEPT;
4534 }
4535
4536 static unsigned int selinux_ip_postroute(struct sk_buff *skb, int ifindex,
4537                                          u16 family)
4538 {
4539         u32 secmark_perm;
4540         u32 peer_sid;
4541         struct sock *sk;
4542         struct common_audit_data ad;
4543         char *addrp;
4544         u8 secmark_active;
4545         u8 peerlbl_active;
4546
4547         /* If any sort of compatibility mode is enabled then handoff processing
4548          * to the selinux_ip_postroute_compat() function to deal with the
4549          * special handling.  We do this in an attempt to keep this function
4550          * as fast and as clean as possible. */
4551         if (!selinux_policycap_netpeer)
4552                 return selinux_ip_postroute_compat(skb, ifindex, family);
4553 #ifdef CONFIG_XFRM
4554         /* If skb->dst->xfrm is non-NULL then the packet is undergoing an IPsec
4555          * packet transformation so allow the packet to pass without any checks
4556          * since we'll have another chance to perform access control checks
4557          * when the packet is on it's final way out.
4558          * NOTE: there appear to be some IPv6 multicast cases where skb->dst
4559          *       is NULL, in this case go ahead and apply access control. */
4560         if (skb_dst(skb) != NULL && skb_dst(skb)->xfrm != NULL)
4561                 return NF_ACCEPT;
4562 #endif
4563         secmark_active = selinux_secmark_enabled();
4564         peerlbl_active = netlbl_enabled() || selinux_xfrm_enabled();
4565         if (!secmark_active && !peerlbl_active)
4566                 return NF_ACCEPT;
4567
4568         /* if the packet is being forwarded then get the peer label from the
4569          * packet itself; otherwise check to see if it is from a local
4570          * application or the kernel, if from an application get the peer label
4571          * from the sending socket, otherwise use the kernel's sid */
4572         sk = skb->sk;
4573         if (sk == NULL) {
4574                 switch (family) {
4575                 case PF_INET:
4576                         if (IPCB(skb)->flags & IPSKB_FORWARDED)
4577                                 secmark_perm = PACKET__FORWARD_OUT;
4578                         else
4579                                 secmark_perm = PACKET__SEND;
4580                         break;
4581                 case PF_INET6:
4582                         if (IP6CB(skb)->flags & IP6SKB_FORWARDED)
4583                                 secmark_perm = PACKET__FORWARD_OUT;
4584                         else
4585                                 secmark_perm = PACKET__SEND;
4586                         break;
4587                 default:
4588                         return NF_DROP;
4589                 }
4590                 if (secmark_perm == PACKET__FORWARD_OUT) {
4591                         if (selinux_skb_peerlbl_sid(skb, family, &peer_sid))
4592                                 return NF_DROP;
4593                 } else
4594                         peer_sid = SECINITSID_KERNEL;
4595         } else {
4596                 struct sk_security_struct *sksec = sk->sk_security;
4597                 peer_sid = sksec->sid;
4598                 secmark_perm = PACKET__SEND;
4599         }
4600
4601         COMMON_AUDIT_DATA_INIT(&ad, NET);
4602         ad.u.net.netif = ifindex;
4603         ad.u.net.family = family;
4604         if (selinux_parse_skb(skb, &ad, &addrp, 0, NULL))
4605                 return NF_DROP;
4606
4607         if (secmark_active)
4608                 if (avc_has_perm(peer_sid, skb->secmark,
4609                                  SECCLASS_PACKET, secmark_perm, &ad))
4610                         return NF_DROP;
4611
4612         if (peerlbl_active) {
4613                 u32 if_sid;
4614                 u32 node_sid;
4615
4616                 if (sel_netif_sid(ifindex, &if_sid))
4617                         return NF_DROP;
4618                 if (avc_has_perm(peer_sid, if_sid,
4619                                  SECCLASS_NETIF, NETIF__EGRESS, &ad))
4620                         return NF_DROP;
4621
4622                 if (sel_netnode_sid(addrp, family, &node_sid))
4623                         return NF_DROP;
4624                 if (avc_has_perm(peer_sid, node_sid,
4625                                  SECCLASS_NODE, NODE__SENDTO, &ad))
4626                         return NF_DROP;
4627         }
4628
4629         return NF_ACCEPT;
4630 }
4631
4632 static unsigned int selinux_ipv4_postroute(unsigned int hooknum,
4633                                            struct sk_buff *skb,
4634                                            const struct net_device *in,
4635                                            const struct net_device *out,
4636                                            int (*okfn)(struct sk_buff *))
4637 {
4638         return selinux_ip_postroute(skb, out->ifindex, PF_INET);
4639 }
4640
4641 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
4642 static unsigned int selinux_ipv6_postroute(unsigned int hooknum,
4643                                            struct sk_buff *skb,
4644                                            const struct net_device *in,
4645                                            const struct net_device *out,
4646                                            int (*okfn)(struct sk_buff *))
4647 {
4648         return selinux_ip_postroute(skb, out->ifindex, PF_INET6);
4649 }
4650 #endif  /* IPV6 */
4651
4652 #endif  /* CONFIG_NETFILTER */
4653
4654 static int selinux_netlink_send(struct sock *sk, struct sk_buff *skb)
4655 {
4656         int err;
4657
4658         err = cap_netlink_send(sk, skb);
4659         if (err)
4660                 return err;
4661
4662         return selinux_nlmsg_perm(sk, skb);
4663 }
4664
4665 static int selinux_netlink_recv(struct sk_buff *skb, int capability)
4666 {
4667         int err;
4668         struct common_audit_data ad;
4669
4670         err = cap_netlink_recv(skb, capability);
4671         if (err)
4672                 return err;
4673
4674         COMMON_AUDIT_DATA_INIT(&ad, CAP);
4675         ad.u.cap = capability;
4676
4677         return avc_has_perm(NETLINK_CB(skb).sid, NETLINK_CB(skb).sid,
4678                             SECCLASS_CAPABILITY, CAP_TO_MASK(capability), &ad);
4679 }
4680
4681 static int ipc_alloc_security(struct task_struct *task,
4682                               struct kern_ipc_perm *perm,
4683                               u16 sclass)
4684 {
4685         struct ipc_security_struct *isec;
4686         u32 sid;
4687
4688         isec = kzalloc(sizeof(struct ipc_security_struct), GFP_KERNEL);
4689         if (!isec)
4690                 return -ENOMEM;
4691
4692         sid = task_sid(task);
4693         isec->sclass = sclass;
4694         isec->sid = sid;
4695         perm->security = isec;
4696
4697         return 0;
4698 }
4699
4700 static void ipc_free_security(struct kern_ipc_perm *perm)
4701 {
4702         struct ipc_security_struct *isec = perm->security;
4703         perm->security = NULL;
4704         kfree(isec);
4705 }
4706
4707 static int msg_msg_alloc_security(struct msg_msg *msg)
4708 {
4709         struct msg_security_struct *msec;
4710
4711         msec = kzalloc(sizeof(struct msg_security_struct), GFP_KERNEL);
4712         if (!msec)
4713                 return -ENOMEM;
4714
4715         msec->sid = SECINITSID_UNLABELED;
4716         msg->security = msec;
4717
4718         return 0;
4719 }
4720
4721 static void msg_msg_free_security(struct msg_msg *msg)
4722 {
4723         struct msg_security_struct *msec = msg->security;
4724
4725         msg->security = NULL;
4726         kfree(msec);
4727 }
4728
4729 static int ipc_has_perm(struct kern_ipc_perm *ipc_perms,
4730                         u32 perms)
4731 {
4732         struct ipc_security_struct *isec;
4733         struct common_audit_data ad;
4734         u32 sid = current_sid();
4735
4736         isec = ipc_perms->security;
4737
4738         COMMON_AUDIT_DATA_INIT(&ad, IPC);
4739         ad.u.ipc_id = ipc_perms->key;
4740
4741         return avc_has_perm(sid, isec->sid, isec->sclass, perms, &ad);
4742 }
4743
4744 static int selinux_msg_msg_alloc_security(struct msg_msg *msg)
4745 {
4746         return msg_msg_alloc_security(msg);
4747 }
4748
4749 static void selinux_msg_msg_free_security(struct msg_msg *msg)
4750 {
4751         msg_msg_free_security(msg);
4752 }
4753
4754 /* message queue security operations */
4755 static int selinux_msg_queue_alloc_security(struct msg_queue *msq)
4756 {
4757         struct ipc_security_struct *isec;
4758         struct common_audit_data ad;
4759         u32 sid = current_sid();
4760         int rc;
4761
4762         rc = ipc_alloc_security(current, &msq->q_perm, SECCLASS_MSGQ);
4763         if (rc)
4764                 return rc;
4765
4766         isec = msq->q_perm.security;
4767
4768         COMMON_AUDIT_DATA_INIT(&ad, IPC);
4769         ad.u.ipc_id = msq->q_perm.key;
4770
4771         rc = avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
4772                           MSGQ__CREATE, &ad);
4773         if (rc) {
4774                 ipc_free_security(&msq->q_perm);
4775                 return rc;
4776         }
4777         return 0;
4778 }
4779
4780 static void selinux_msg_queue_free_security(struct msg_queue *msq)
4781 {
4782         ipc_free_security(&msq->q_perm);
4783 }
4784
4785 static int selinux_msg_queue_associate(struct msg_queue *msq, int msqflg)
4786 {
4787         struct ipc_security_struct *isec;
4788         struct common_audit_data ad;
4789         u32 sid = current_sid();
4790
4791         isec = msq->q_perm.security;
4792
4793         COMMON_AUDIT_DATA_INIT(&ad, IPC);
4794         ad.u.ipc_id = msq->q_perm.key;
4795
4796         return avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
4797                             MSGQ__ASSOCIATE, &ad);
4798 }
4799
4800 static int selinux_msg_queue_msgctl(struct msg_queue *msq, int cmd)
4801 {
4802         int err;
4803         int perms;
4804
4805         switch (cmd) {
4806         case IPC_INFO:
4807         case MSG_INFO:
4808                 /* No specific object, just general system-wide information. */
4809                 return task_has_system(current, SYSTEM__IPC_INFO);
4810         case IPC_STAT:
4811         case MSG_STAT:
4812                 perms = MSGQ__GETATTR | MSGQ__ASSOCIATE;
4813                 break;
4814         case IPC_SET:
4815                 perms = MSGQ__SETATTR;
4816                 break;
4817         case IPC_RMID:
4818                 perms = MSGQ__DESTROY;
4819                 break;
4820         default:
4821                 return 0;
4822         }
4823
4824         err = ipc_has_perm(&msq->q_perm, perms);
4825         return err;
4826 }
4827
4828 static int selinux_msg_queue_msgsnd(struct msg_queue *msq, struct msg_msg *msg, int msqflg)
4829 {
4830         struct ipc_security_struct *isec;
4831         struct msg_security_struct *msec;
4832         struct common_audit_data ad;
4833         u32 sid = current_sid();
4834         int rc;
4835
4836         isec = msq->q_perm.security;
4837         msec = msg->security;
4838
4839         /*
4840          * First time through, need to assign label to the message
4841          */
4842         if (msec->sid == SECINITSID_UNLABELED) {
4843                 /*
4844                  * Compute new sid based on current process and
4845                  * message queue this message will be stored in
4846                  */
4847                 rc = security_transition_sid(sid, isec->sid, SECCLASS_MSG,
4848                                              &msec->sid);
4849                 if (rc)
4850                         return rc;
4851         }
4852
4853         COMMON_AUDIT_DATA_INIT(&ad, IPC);
4854         ad.u.ipc_id = msq->q_perm.key;
4855
4856         /* Can this process write to the queue? */
4857         rc = avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
4858                           MSGQ__WRITE, &ad);
4859         if (!rc)
4860                 /* Can this process send the message */
4861                 rc = avc_has_perm(sid, msec->sid, SECCLASS_MSG,
4862                                   MSG__SEND, &ad);
4863         if (!rc)
4864                 /* Can the message be put in the queue? */
4865                 rc = avc_has_perm(msec->sid, isec->sid, SECCLASS_MSGQ,
4866                                   MSGQ__ENQUEUE, &ad);
4867
4868         return rc;
4869 }
4870
4871 static int selinux_msg_queue_msgrcv(struct msg_queue *msq, struct msg_msg *msg,
4872                                     struct task_struct *target,
4873                                     long type, int mode)
4874 {
4875         struct ipc_security_struct *isec;
4876         struct msg_security_struct *msec;
4877         struct common_audit_data ad;
4878         u32 sid = task_sid(target);
4879         int rc;
4880
4881         isec = msq->q_perm.security;
4882         msec = msg->security;
4883
4884         COMMON_AUDIT_DATA_INIT(&ad, IPC);
4885         ad.u.ipc_id = msq->q_perm.key;
4886
4887         rc = avc_has_perm(sid, isec->sid,
4888                           SECCLASS_MSGQ, MSGQ__READ, &ad);
4889         if (!rc)
4890                 rc = avc_has_perm(sid, msec->sid,
4891                                   SECCLASS_MSG, MSG__RECEIVE, &ad);
4892         return rc;
4893 }
4894
4895 /* Shared Memory security operations */
4896 static int selinux_shm_alloc_security(struct shmid_kernel *shp)
4897 {
4898         struct ipc_security_struct *isec;
4899         struct common_audit_data ad;
4900         u32 sid = current_sid();
4901         int rc;
4902
4903         rc = ipc_alloc_security(current, &shp->shm_perm, SECCLASS_SHM);
4904         if (rc)
4905                 return rc;
4906
4907         isec = shp->shm_perm.security;
4908
4909         COMMON_AUDIT_DATA_INIT(&ad, IPC);
4910         ad.u.ipc_id = shp->shm_perm.key;
4911
4912         rc = avc_has_perm(sid, isec->sid, SECCLASS_SHM,
4913                           SHM__CREATE, &ad);
4914         if (rc) {
4915                 ipc_free_security(&shp->shm_perm);
4916                 return rc;
4917         }
4918         return 0;
4919 }
4920
4921 static void selinux_shm_free_security(struct shmid_kernel *shp)
4922 {
4923         ipc_free_security(&shp->shm_perm);
4924 }
4925
4926 static int selinux_shm_associate(struct shmid_kernel *shp, int shmflg)
4927 {
4928         struct ipc_security_struct *isec;
4929         struct common_audit_data ad;
4930         u32 sid = current_sid();
4931
4932         isec = shp->shm_perm.security;
4933
4934         COMMON_AUDIT_DATA_INIT(&ad, IPC);
4935         ad.u.ipc_id = shp->shm_perm.key;
4936
4937         return avc_has_perm(sid, isec->sid, SECCLASS_SHM,
4938                             SHM__ASSOCIATE, &ad);
4939 }
4940
4941 /* Note, at this point, shp is locked down */
4942 static int selinux_shm_shmctl(struct shmid_kernel *shp, int cmd)
4943 {
4944         int perms;
4945         int err;
4946
4947         switch (cmd) {
4948         case IPC_INFO:
4949         case SHM_INFO:
4950                 /* No specific object, just general system-wide information. */
4951                 return task_has_system(current, SYSTEM__IPC_INFO);
4952         case IPC_STAT:
4953         case SHM_STAT:
4954                 perms = SHM__GETATTR | SHM__ASSOCIATE;
4955                 break;
4956         case IPC_SET:
4957                 perms = SHM__SETATTR;
4958                 break;
4959         case SHM_LOCK:
4960         case SHM_UNLOCK:
4961                 perms = SHM__LOCK;
4962                 break;
4963         case IPC_RMID:
4964                 perms = SHM__DESTROY;
4965                 break;
4966         default:
4967                 return 0;
4968         }
4969
4970         err = ipc_has_perm(&shp->shm_perm, perms);
4971         return err;
4972 }
4973
4974 static int selinux_shm_shmat(struct shmid_kernel *shp,
4975                              char __user *shmaddr, int shmflg)
4976 {
4977         u32 perms;
4978
4979         if (shmflg & SHM_RDONLY)
4980                 perms = SHM__READ;
4981         else
4982                 perms = SHM__READ | SHM__WRITE;
4983
4984         return ipc_has_perm(&shp->shm_perm, perms);
4985 }
4986
4987 /* Semaphore security operations */
4988 static int selinux_sem_alloc_security(struct sem_array *sma)
4989 {
4990         struct ipc_security_struct *isec;
4991         struct common_audit_data ad;
4992         u32 sid = current_sid();
4993         int rc;
4994
4995         rc = ipc_alloc_security(current, &sma->sem_perm, SECCLASS_SEM);
4996         if (rc)
4997                 return rc;
4998
4999         isec = sma->sem_perm.security;
5000
5001         COMMON_AUDIT_DATA_INIT(&ad, IPC);
5002         ad.u.ipc_id = sma->sem_perm.key;
5003
5004         rc = avc_has_perm(sid, isec->sid, SECCLASS_SEM,
5005                           SEM__CREATE, &ad);
5006         if (rc) {
5007                 ipc_free_security(&sma->sem_perm);
5008                 return rc;
5009         }
5010         return 0;
5011 }
5012
5013 static void selinux_sem_free_security(struct sem_array *sma)
5014 {
5015         ipc_free_security(&sma->sem_perm);
5016 }
5017
5018 static int selinux_sem_associate(struct sem_array *sma, int semflg)
5019 {
5020         struct ipc_security_struct *isec;
5021         struct common_audit_data ad;
5022         u32 sid = current_sid();
5023
5024         isec = sma->sem_perm.security;
5025
5026         COMMON_AUDIT_DATA_INIT(&ad, IPC);
5027         ad.u.ipc_id = sma->sem_perm.key;
5028
5029         return avc_has_perm(sid, isec->sid, SECCLASS_SEM,
5030                             SEM__ASSOCIATE, &ad);
5031 }
5032
5033 /* Note, at this point, sma is locked down */
5034 static int selinux_sem_semctl(struct sem_array *sma, int cmd)
5035 {
5036         int err;
5037         u32 perms;
5038
5039         switch (cmd) {
5040         case IPC_INFO:
5041         case SEM_INFO:
5042                 /* No specific object, just general system-wide information. */
5043                 return task_has_system(current, SYSTEM__IPC_INFO);
5044         case GETPID:
5045         case GETNCNT:
5046         case GETZCNT:
5047                 perms = SEM__GETATTR;
5048                 break;
5049         case GETVAL:
5050         case GETALL:
5051                 perms = SEM__READ;
5052                 break;
5053         case SETVAL:
5054         case SETALL:
5055                 perms = SEM__WRITE;
5056                 break;
5057         case IPC_RMID:
5058                 perms = SEM__DESTROY;
5059                 break;
5060         case IPC_SET:
5061                 perms = SEM__SETATTR;
5062                 break;
5063         case IPC_STAT:
5064         case SEM_STAT:
5065                 perms = SEM__GETATTR | SEM__ASSOCIATE;
5066                 break;
5067         default:
5068                 return 0;
5069         }
5070
5071         err = ipc_has_perm(&sma->sem_perm, perms);
5072         return err;
5073 }
5074
5075 static int selinux_sem_semop(struct sem_array *sma,
5076                              struct sembuf *sops, unsigned nsops, int alter)
5077 {
5078         u32 perms;
5079
5080         if (alter)
5081                 perms = SEM__READ | SEM__WRITE;
5082         else
5083                 perms = SEM__READ;
5084
5085         return ipc_has_perm(&sma->sem_perm, perms);
5086 }
5087
5088 static int selinux_ipc_permission(struct kern_ipc_perm *ipcp, short flag)
5089 {
5090         u32 av = 0;
5091
5092         av = 0;
5093         if (flag & S_IRUGO)
5094                 av |= IPC__UNIX_READ;
5095         if (flag & S_IWUGO)
5096                 av |= IPC__UNIX_WRITE;
5097
5098         if (av == 0)
5099                 return 0;
5100
5101         return ipc_has_perm(ipcp, av);
5102 }
5103
5104 static void selinux_ipc_getsecid(struct kern_ipc_perm *ipcp, u32 *secid)
5105 {
5106         struct ipc_security_struct *isec = ipcp->security;
5107         *secid = isec->sid;
5108 }
5109
5110 static void selinux_d_instantiate(struct dentry *dentry, struct inode *inode)
5111 {
5112         if (inode)
5113                 inode_doinit_with_dentry(inode, dentry);
5114 }
5115
5116 static int selinux_getprocattr(struct task_struct *p,
5117                                char *name, char **value)
5118 {
5119         const struct task_security_struct *__tsec;
5120         u32 sid;
5121         int error;
5122         unsigned len;
5123
5124         if (current != p) {
5125                 error = current_has_perm(p, PROCESS__GETATTR);
5126                 if (error)
5127                         return error;
5128         }
5129
5130         rcu_read_lock();
5131         __tsec = __task_cred(p)->security;
5132
5133         if (!strcmp(name, "current"))
5134                 sid = __tsec->sid;
5135         else if (!strcmp(name, "prev"))
5136                 sid = __tsec->osid;
5137         else if (!strcmp(name, "exec"))
5138                 sid = __tsec->exec_sid;
5139         else if (!strcmp(name, "fscreate"))
5140                 sid = __tsec->create_sid;
5141         else if (!strcmp(name, "keycreate"))
5142                 sid = __tsec->keycreate_sid;
5143         else if (!strcmp(name, "sockcreate"))
5144                 sid = __tsec->sockcreate_sid;
5145         else
5146                 goto invalid;
5147         rcu_read_unlock();
5148
5149         if (!sid)
5150                 return 0;
5151
5152         error = security_sid_to_context(sid, value, &len);
5153         if (error)
5154                 return error;
5155         return len;
5156
5157 invalid:
5158         rcu_read_unlock();
5159         return -EINVAL;
5160 }
5161
5162 static int selinux_setprocattr(struct task_struct *p,
5163                                char *name, void *value, size_t size)
5164 {
5165         struct task_security_struct *tsec;
5166         struct task_struct *tracer;
5167         struct cred *new;
5168         u32 sid = 0, ptsid;
5169         int error;
5170         char *str = value;
5171
5172         if (current != p) {
5173                 /* SELinux only allows a process to change its own
5174                    security attributes. */
5175                 return -EACCES;
5176         }
5177
5178         /*
5179          * Basic control over ability to set these attributes at all.
5180          * current == p, but we'll pass them separately in case the
5181          * above restriction is ever removed.
5182          */
5183         if (!strcmp(name, "exec"))
5184                 error = current_has_perm(p, PROCESS__SETEXEC);
5185         else if (!strcmp(name, "fscreate"))
5186                 error = current_has_perm(p, PROCESS__SETFSCREATE);
5187         else if (!strcmp(name, "keycreate"))
5188                 error = current_has_perm(p, PROCESS__SETKEYCREATE);
5189         else if (!strcmp(name, "sockcreate"))
5190                 error = current_has_perm(p, PROCESS__SETSOCKCREATE);
5191         else if (!strcmp(name, "current"))
5192                 error = current_has_perm(p, PROCESS__SETCURRENT);
5193         else
5194                 error = -EINVAL;
5195         if (error)
5196                 return error;
5197
5198         /* Obtain a SID for the context, if one was specified. */
5199         if (size && str[1] && str[1] != '\n') {
5200                 if (str[size-1] == '\n') {
5201                         str[size-1] = 0;
5202                         size--;
5203                 }
5204                 error = security_context_to_sid(value, size, &sid);
5205                 if (error == -EINVAL && !strcmp(name, "fscreate")) {
5206                         if (!capable(CAP_MAC_ADMIN))
5207                                 return error;
5208                         error = security_context_to_sid_force(value, size,
5209                                                               &sid);
5210                 }
5211                 if (error)
5212                         return error;
5213         }
5214
5215         new = prepare_creds();
5216         if (!new)
5217                 return -ENOMEM;
5218
5219         /* Permission checking based on the specified context is
5220            performed during the actual operation (execve,
5221            open/mkdir/...), when we know the full context of the
5222            operation.  See selinux_bprm_set_creds for the execve
5223            checks and may_create for the file creation checks. The
5224            operation will then fail if the context is not permitted. */
5225         tsec = new->security;
5226         if (!strcmp(name, "exec")) {
5227                 tsec->exec_sid = sid;
5228         } else if (!strcmp(name, "fscreate")) {
5229                 tsec->create_sid = sid;
5230         } else if (!strcmp(name, "keycreate")) {
5231                 error = may_create_key(sid, p);
5232                 if (error)
5233                         goto abort_change;
5234                 tsec->keycreate_sid = sid;
5235         } else if (!strcmp(name, "sockcreate")) {
5236                 tsec->sockcreate_sid = sid;
5237         } else if (!strcmp(name, "current")) {
5238                 error = -EINVAL;
5239                 if (sid == 0)
5240                         goto abort_change;
5241
5242                 /* Only allow single threaded processes to change context */
5243                 error = -EPERM;
5244                 if (!current_is_single_threaded()) {
5245                         error = security_bounded_transition(tsec->sid, sid);
5246                         if (error)
5247                                 goto abort_change;
5248                 }
5249
5250                 /* Check permissions for the transition. */
5251                 error = avc_has_perm(tsec->sid, sid, SECCLASS_PROCESS,
5252                                      PROCESS__DYNTRANSITION, NULL);
5253                 if (error)
5254                         goto abort_change;
5255
5256                 /* Check for ptracing, and update the task SID if ok.
5257                    Otherwise, leave SID unchanged and fail. */
5258                 ptsid = 0;
5259                 task_lock(p);
5260                 tracer = tracehook_tracer_task(p);
5261                 if (tracer)
5262                         ptsid = task_sid(tracer);
5263                 task_unlock(p);
5264
5265                 if (tracer) {
5266                         error = avc_has_perm(ptsid, sid, SECCLASS_PROCESS,
5267                                              PROCESS__PTRACE, NULL);
5268                         if (error)
5269                                 goto abort_change;
5270                 }
5271
5272                 tsec->sid = sid;
5273         } else {
5274                 error = -EINVAL;
5275                 goto abort_change;
5276         }
5277
5278         commit_creds(new);
5279         return size;
5280
5281 abort_change:
5282         abort_creds(new);
5283         return error;
5284 }
5285
5286 static int selinux_secid_to_secctx(u32 secid, char **secdata, u32 *seclen)
5287 {
5288         return security_sid_to_context(secid, secdata, seclen);
5289 }
5290
5291 static int selinux_secctx_to_secid(const char *secdata, u32 seclen, u32 *secid)
5292 {
5293         return security_context_to_sid(secdata, seclen, secid);
5294 }
5295
5296 static void selinux_release_secctx(char *secdata, u32 seclen)
5297 {
5298         kfree(secdata);
5299 }
5300
5301 /*
5302  *      called with inode->i_mutex locked
5303  */
5304 static int selinux_inode_notifysecctx(struct inode *inode, void *ctx, u32 ctxlen)
5305 {
5306         return selinux_inode_setsecurity(inode, XATTR_SELINUX_SUFFIX, ctx, ctxlen, 0);
5307 }
5308
5309 /*
5310  *      called with inode->i_mutex locked
5311  */
5312 static int selinux_inode_setsecctx(struct dentry *dentry, void *ctx, u32 ctxlen)
5313 {
5314         return __vfs_setxattr_noperm(dentry, XATTR_NAME_SELINUX, ctx, ctxlen, 0);
5315 }
5316
5317 static int selinux_inode_getsecctx(struct inode *inode, void **ctx, u32 *ctxlen)
5318 {
5319         int len = 0;
5320         len = selinux_inode_getsecurity(inode, XATTR_SELINUX_SUFFIX,
5321                                                 ctx, true);
5322         if (len < 0)
5323                 return len;
5324         *ctxlen = len;
5325         return 0;
5326 }
5327 #ifdef CONFIG_KEYS
5328
5329 static int selinux_key_alloc(struct key *k, const struct cred *cred,
5330                              unsigned long flags)
5331 {
5332         const struct task_security_struct *tsec;
5333         struct key_security_struct *ksec;
5334
5335         ksec = kzalloc(sizeof(struct key_security_struct), GFP_KERNEL);
5336         if (!ksec)
5337                 return -ENOMEM;
5338
5339         tsec = cred->security;
5340         if (tsec->keycreate_sid)
5341                 ksec->sid = tsec->keycreate_sid;
5342         else
5343                 ksec->sid = tsec->sid;
5344
5345         k->security = ksec;
5346         return 0;
5347 }
5348
5349 static void selinux_key_free(struct key *k)
5350 {
5351         struct key_security_struct *ksec = k->security;
5352
5353         k->security = NULL;
5354         kfree(ksec);
5355 }
5356
5357 static int selinux_key_permission(key_ref_t key_ref,
5358                                   const struct cred *cred,
5359                                   key_perm_t perm)
5360 {
5361         struct key *key;
5362         struct key_security_struct *ksec;
5363         u32 sid;
5364
5365         /* if no specific permissions are requested, we skip the
5366            permission check. No serious, additional covert channels
5367            appear to be created. */
5368         if (perm == 0)
5369                 return 0;
5370
5371         sid = cred_sid(cred);
5372
5373         key = key_ref_to_ptr(key_ref);
5374         ksec = key->security;
5375
5376         return avc_has_perm(sid, ksec->sid, SECCLASS_KEY, perm, NULL);
5377 }
5378
5379 static int selinux_key_getsecurity(struct key *key, char **_buffer)
5380 {
5381         struct key_security_struct *ksec = key->security;
5382         char *context = NULL;
5383         unsigned len;
5384         int rc;
5385
5386         rc = security_sid_to_context(ksec->sid, &context, &len);
5387         if (!rc)
5388                 rc = len;
5389         *_buffer = context;
5390         return rc;
5391 }
5392
5393 #endif
5394
5395 static struct security_operations selinux_ops = {
5396         .name =                         "selinux",
5397
5398         .ptrace_access_check =          selinux_ptrace_access_check,
5399         .ptrace_traceme =               selinux_ptrace_traceme,
5400         .capget =                       selinux_capget,
5401         .capset =                       selinux_capset,
5402         .sysctl =                       selinux_sysctl,
5403         .capable =                      selinux_capable,
5404         .quotactl =                     selinux_quotactl,
5405         .quota_on =                     selinux_quota_on,
5406         .syslog =                       selinux_syslog,
5407         .vm_enough_memory =             selinux_vm_enough_memory,
5408
5409         .netlink_send =                 selinux_netlink_send,
5410         .netlink_recv =                 selinux_netlink_recv,
5411
5412         .bprm_set_creds =               selinux_bprm_set_creds,
5413         .bprm_committing_creds =        selinux_bprm_committing_creds,
5414         .bprm_committed_creds =         selinux_bprm_committed_creds,
5415         .bprm_secureexec =              selinux_bprm_secureexec,
5416
5417         .sb_alloc_security =            selinux_sb_alloc_security,
5418         .sb_free_security =             selinux_sb_free_security,
5419         .sb_copy_data =                 selinux_sb_copy_data,
5420         .sb_kern_mount =                selinux_sb_kern_mount,
5421         .sb_show_options =              selinux_sb_show_options,
5422         .sb_statfs =                    selinux_sb_statfs,
5423         .sb_mount =                     selinux_mount,
5424         .sb_umount =                    selinux_umount,
5425         .sb_set_mnt_opts =              selinux_set_mnt_opts,
5426         .sb_clone_mnt_opts =            selinux_sb_clone_mnt_opts,
5427         .sb_parse_opts_str =            selinux_parse_opts_str,
5428
5429
5430         .inode_alloc_security =         selinux_inode_alloc_security,
5431         .inode_free_security =          selinux_inode_free_security,
5432         .inode_init_security =          selinux_inode_init_security,
5433         .inode_create =                 selinux_inode_create,
5434         .inode_link =                   selinux_inode_link,
5435         .inode_unlink =                 selinux_inode_unlink,
5436         .inode_symlink =                selinux_inode_symlink,
5437         .inode_mkdir =                  selinux_inode_mkdir,
5438         .inode_rmdir =                  selinux_inode_rmdir,
5439         .inode_mknod =                  selinux_inode_mknod,
5440         .inode_rename =                 selinux_inode_rename,
5441         .inode_readlink =               selinux_inode_readlink,
5442         .inode_follow_link =            selinux_inode_follow_link,
5443         .inode_permission =             selinux_inode_permission,
5444         .inode_setattr =                selinux_inode_setattr,
5445         .inode_getattr =                selinux_inode_getattr,
5446         .inode_setxattr =               selinux_inode_setxattr,
5447         .inode_post_setxattr =          selinux_inode_post_setxattr,
5448         .inode_getxattr =               selinux_inode_getxattr,
5449         .inode_listxattr =              selinux_inode_listxattr,
5450         .inode_removexattr =            selinux_inode_removexattr,
5451         .inode_getsecurity =            selinux_inode_getsecurity,
5452         .inode_setsecurity =            selinux_inode_setsecurity,
5453         .inode_listsecurity =           selinux_inode_listsecurity,
5454         .inode_getsecid =               selinux_inode_getsecid,
5455
5456         .file_permission =              selinux_file_permission,
5457         .file_alloc_security =          selinux_file_alloc_security,
5458         .file_free_security =           selinux_file_free_security,
5459         .file_ioctl =                   selinux_file_ioctl,
5460         .file_mmap =                    selinux_file_mmap,
5461         .file_mprotect =                selinux_file_mprotect,
5462         .file_lock =                    selinux_file_lock,
5463         .file_fcntl =                   selinux_file_fcntl,
5464         .file_set_fowner =              selinux_file_set_fowner,
5465         .file_send_sigiotask =          selinux_file_send_sigiotask,
5466         .file_receive =                 selinux_file_receive,
5467
5468         .dentry_open =                  selinux_dentry_open,
5469
5470         .task_create =                  selinux_task_create,
5471         .cred_alloc_blank =             selinux_cred_alloc_blank,
5472         .cred_free =                    selinux_cred_free,
5473         .cred_prepare =                 selinux_cred_prepare,
5474         .cred_transfer =                selinux_cred_transfer,
5475         .kernel_act_as =                selinux_kernel_act_as,
5476         .kernel_create_files_as =       selinux_kernel_create_files_as,
5477         .kernel_module_request =        selinux_kernel_module_request,
5478         .task_setpgid =                 selinux_task_setpgid,
5479         .task_getpgid =                 selinux_task_getpgid,
5480         .task_getsid =                  selinux_task_getsid,
5481         .task_getsecid =                selinux_task_getsecid,
5482         .task_setnice =                 selinux_task_setnice,
5483         .task_setioprio =               selinux_task_setioprio,
5484         .task_getioprio =               selinux_task_getioprio,
5485         .task_setrlimit =               selinux_task_setrlimit,
5486         .task_setscheduler =            selinux_task_setscheduler,
5487         .task_getscheduler =            selinux_task_getscheduler,
5488         .task_movememory =              selinux_task_movememory,
5489         .task_kill =                    selinux_task_kill,
5490         .task_wait =                    selinux_task_wait,
5491         .task_to_inode =                selinux_task_to_inode,
5492
5493         .ipc_permission =               selinux_ipc_permission,
5494         .ipc_getsecid =                 selinux_ipc_getsecid,
5495
5496         .msg_msg_alloc_security =       selinux_msg_msg_alloc_security,
5497         .msg_msg_free_security =        selinux_msg_msg_free_security,
5498
5499         .msg_queue_alloc_security =     selinux_msg_queue_alloc_security,
5500         .msg_queue_free_security =      selinux_msg_queue_free_security,
5501         .msg_queue_associate =          selinux_msg_queue_associate,
5502         .msg_queue_msgctl =             selinux_msg_queue_msgctl,
5503         .msg_queue_msgsnd =             selinux_msg_queue_msgsnd,
5504         .msg_queue_msgrcv =             selinux_msg_queue_msgrcv,
5505
5506         .shm_alloc_security =           selinux_shm_alloc_security,
5507         .shm_free_security =            selinux_shm_free_security,
5508         .shm_associate =                selinux_shm_associate,
5509         .shm_shmctl =                   selinux_shm_shmctl,
5510         .shm_shmat =                    selinux_shm_shmat,
5511
5512         .sem_alloc_security =           selinux_sem_alloc_security,
5513         .sem_free_security =            selinux_sem_free_security,
5514         .sem_associate =                selinux_sem_associate,
5515         .sem_semctl =                   selinux_sem_semctl,
5516         .sem_semop =                    selinux_sem_semop,
5517
5518         .d_instantiate =                selinux_d_instantiate,
5519
5520         .getprocattr =                  selinux_getprocattr,
5521         .setprocattr =                  selinux_setprocattr,
5522
5523         .secid_to_secctx =              selinux_secid_to_secctx,
5524         .secctx_to_secid =              selinux_secctx_to_secid,
5525         .release_secctx =               selinux_release_secctx,
5526         .inode_notifysecctx =           selinux_inode_notifysecctx,
5527         .inode_setsecctx =              selinux_inode_setsecctx,
5528         .inode_getsecctx =              selinux_inode_getsecctx,
5529
5530         .unix_stream_connect =          selinux_socket_unix_stream_connect,
5531         .unix_may_send =                selinux_socket_unix_may_send,
5532
5533         .socket_create =                selinux_socket_create,
5534         .socket_post_create =           selinux_socket_post_create,
5535         .socket_bind =                  selinux_socket_bind,
5536         .socket_connect =               selinux_socket_connect,
5537         .socket_listen =                selinux_socket_listen,
5538         .socket_accept =                selinux_socket_accept,
5539         .socket_sendmsg =               selinux_socket_sendmsg,
5540         .socket_recvmsg =               selinux_socket_recvmsg,
5541         .socket_getsockname =           selinux_socket_getsockname,
5542         .socket_getpeername =           selinux_socket_getpeername,
5543         .socket_getsockopt =            selinux_socket_getsockopt,
5544         .socket_setsockopt =            selinux_socket_setsockopt,
5545         .socket_shutdown =              selinux_socket_shutdown,
5546         .socket_sock_rcv_skb =          selinux_socket_sock_rcv_skb,
5547         .socket_getpeersec_stream =     selinux_socket_getpeersec_stream,
5548         .socket_getpeersec_dgram =      selinux_socket_getpeersec_dgram,
5549         .sk_alloc_security =            selinux_sk_alloc_security,
5550         .sk_free_security =             selinux_sk_free_security,
5551         .sk_clone_security =            selinux_sk_clone_security,
5552         .sk_getsecid =                  selinux_sk_getsecid,
5553         .sock_graft =                   selinux_sock_graft,
5554         .inet_conn_request =            selinux_inet_conn_request,
5555         .inet_csk_clone =               selinux_inet_csk_clone,
5556         .inet_conn_established =        selinux_inet_conn_established,
5557         .secmark_relabel_packet =       selinux_secmark_relabel_packet,
5558         .secmark_refcount_inc =         selinux_secmark_refcount_inc,
5559         .secmark_refcount_dec =         selinux_secmark_refcount_dec,
5560         .req_classify_flow =            selinux_req_classify_flow,
5561         .tun_dev_create =               selinux_tun_dev_create,
5562         .tun_dev_post_create =          selinux_tun_dev_post_create,
5563         .tun_dev_attach =               selinux_tun_dev_attach,
5564
5565 #ifdef CONFIG_SECURITY_NETWORK_XFRM
5566         .xfrm_policy_alloc_security =   selinux_xfrm_policy_alloc,
5567         .xfrm_policy_clone_security =   selinux_xfrm_policy_clone,
5568         .xfrm_policy_free_security =    selinux_xfrm_policy_free,
5569         .xfrm_policy_delete_security =  selinux_xfrm_policy_delete,
5570         .xfrm_state_alloc_security =    selinux_xfrm_state_alloc,
5571         .xfrm_state_free_security =     selinux_xfrm_state_free,
5572         .xfrm_state_delete_security =   selinux_xfrm_state_delete,
5573         .xfrm_policy_lookup =           selinux_xfrm_policy_lookup,
5574         .xfrm_state_pol_flow_match =    selinux_xfrm_state_pol_flow_match,
5575         .xfrm_decode_session =          selinux_xfrm_decode_session,
5576 #endif
5577
5578 #ifdef CONFIG_KEYS
5579         .key_alloc =                    selinux_key_alloc,
5580         .key_free =                     selinux_key_free,
5581         .key_permission =               selinux_key_permission,
5582         .key_getsecurity =              selinux_key_getsecurity,
5583 #endif
5584
5585 #ifdef CONFIG_AUDIT
5586         .audit_rule_init =              selinux_audit_rule_init,
5587         .audit_rule_known =             selinux_audit_rule_known,
5588         .audit_rule_match =             selinux_audit_rule_match,
5589         .audit_rule_free =              selinux_audit_rule_free,
5590 #endif
5591 };
5592
5593 static __init int selinux_init(void)
5594 {
5595         if (!security_module_enable(&selinux_ops)) {
5596                 selinux_enabled = 0;
5597                 return 0;
5598         }
5599
5600         if (!selinux_enabled) {
5601                 printk(KERN_INFO "SELinux:  Disabled at boot.\n");
5602                 return 0;
5603         }
5604
5605         printk(KERN_INFO "SELinux:  Initializing.\n");
5606
5607         /* Set the security state for the initial task. */
5608         cred_init_security();
5609
5610         default_noexec = !(VM_DATA_DEFAULT_FLAGS & VM_EXEC);
5611
5612         sel_inode_cache = kmem_cache_create("selinux_inode_security",
5613                                             sizeof(struct inode_security_struct),
5614                                             0, SLAB_PANIC, NULL);
5615         avc_init();
5616
5617         if (register_security(&selinux_ops))
5618                 panic("SELinux: Unable to register with kernel.\n");
5619
5620         if (selinux_enforcing)
5621                 printk(KERN_DEBUG "SELinux:  Starting in enforcing mode\n");
5622         else
5623                 printk(KERN_DEBUG "SELinux:  Starting in permissive mode\n");
5624
5625         return 0;
5626 }
5627
5628 static void delayed_superblock_init(struct super_block *sb, void *unused)
5629 {
5630         superblock_doinit(sb, NULL);
5631 }
5632
5633 void selinux_complete_init(void)
5634 {
5635         printk(KERN_DEBUG "SELinux:  Completing initialization.\n");
5636
5637         /* Set up any superblocks initialized prior to the policy load. */
5638         printk(KERN_DEBUG "SELinux:  Setting up existing superblocks.\n");
5639         iterate_supers(delayed_superblock_init, NULL);
5640 }
5641
5642 /* SELinux requires early initialization in order to label
5643    all processes and objects when they are created. */
5644 security_initcall(selinux_init);
5645
5646 #if defined(CONFIG_NETFILTER)
5647
5648 static struct nf_hook_ops selinux_ipv4_ops[] = {
5649         {
5650                 .hook =         selinux_ipv4_postroute,
5651                 .owner =        THIS_MODULE,
5652                 .pf =           PF_INET,
5653                 .hooknum =      NF_INET_POST_ROUTING,
5654                 .priority =     NF_IP_PRI_SELINUX_LAST,
5655         },
5656         {
5657                 .hook =         selinux_ipv4_forward,
5658                 .owner =        THIS_MODULE,
5659                 .pf =           PF_INET,
5660                 .hooknum =      NF_INET_FORWARD,
5661                 .priority =     NF_IP_PRI_SELINUX_FIRST,
5662         },
5663         {
5664                 .hook =         selinux_ipv4_output,
5665                 .owner =        THIS_MODULE,
5666                 .pf =           PF_INET,
5667                 .hooknum =      NF_INET_LOCAL_OUT,
5668                 .priority =     NF_IP_PRI_SELINUX_FIRST,
5669         }
5670 };
5671
5672 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
5673
5674 static struct nf_hook_ops selinux_ipv6_ops[] = {
5675         {
5676                 .hook =         selinux_ipv6_postroute,
5677                 .owner =        THIS_MODULE,
5678                 .pf =           PF_INET6,
5679                 .hooknum =      NF_INET_POST_ROUTING,
5680                 .priority =     NF_IP6_PRI_SELINUX_LAST,
5681         },
5682         {
5683                 .hook =         selinux_ipv6_forward,
5684                 .owner =        THIS_MODULE,
5685                 .pf =           PF_INET6,
5686                 .hooknum =      NF_INET_FORWARD,
5687                 .priority =     NF_IP6_PRI_SELINUX_FIRST,
5688         }
5689 };
5690
5691 #endif  /* IPV6 */
5692
5693 static int __init selinux_nf_ip_init(void)
5694 {
5695         int err = 0;
5696
5697         if (!selinux_enabled)
5698                 goto out;
5699
5700         printk(KERN_DEBUG "SELinux:  Registering netfilter hooks\n");
5701
5702         err = nf_register_hooks(selinux_ipv4_ops, ARRAY_SIZE(selinux_ipv4_ops));
5703         if (err)
5704                 panic("SELinux: nf_register_hooks for IPv4: error %d\n", err);
5705
5706 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
5707         err = nf_register_hooks(selinux_ipv6_ops, ARRAY_SIZE(selinux_ipv6_ops));
5708         if (err)
5709                 panic("SELinux: nf_register_hooks for IPv6: error %d\n", err);
5710 #endif  /* IPV6 */
5711
5712 out:
5713         return err;
5714 }
5715
5716 __initcall(selinux_nf_ip_init);
5717
5718 #ifdef CONFIG_SECURITY_SELINUX_DISABLE
5719 static void selinux_nf_ip_exit(void)
5720 {
5721         printk(KERN_DEBUG "SELinux:  Unregistering netfilter hooks\n");
5722
5723         nf_unregister_hooks(selinux_ipv4_ops, ARRAY_SIZE(selinux_ipv4_ops));
5724 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
5725         nf_unregister_hooks(selinux_ipv6_ops, ARRAY_SIZE(selinux_ipv6_ops));
5726 #endif  /* IPV6 */
5727 }
5728 #endif
5729
5730 #else /* CONFIG_NETFILTER */
5731
5732 #ifdef CONFIG_SECURITY_SELINUX_DISABLE
5733 #define selinux_nf_ip_exit()
5734 #endif
5735
5736 #endif /* CONFIG_NETFILTER */
5737
5738 #ifdef CONFIG_SECURITY_SELINUX_DISABLE
5739 static int selinux_disabled;
5740
5741 int selinux_disable(void)
5742 {
5743         extern void exit_sel_fs(void);
5744
5745         if (ss_initialized) {
5746                 /* Not permitted after initial policy load. */
5747                 return -EINVAL;
5748         }
5749
5750         if (selinux_disabled) {
5751                 /* Only do this once. */
5752                 return -EINVAL;
5753         }
5754
5755         printk(KERN_INFO "SELinux:  Disabled at runtime.\n");
5756
5757         selinux_disabled = 1;
5758         selinux_enabled = 0;
5759
5760         reset_security_ops();
5761
5762         /* Try to destroy the avc node cache */
5763         avc_disable();
5764
5765         /* Unregister netfilter hooks. */
5766         selinux_nf_ip_exit();
5767
5768         /* Unregister selinuxfs. */
5769         exit_sel_fs();
5770
5771         return 0;
5772 }
5773 #endif