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 XATTR_SELINUX_SUFFIX "selinux"
  91 #define XATTR_NAME_SELINUX XATTR_SECURITY_PREFIX XATTR_SELINUX_SUFFIX
  92
  93 #define NUM_SEL_MNT_OPTS 5
  94
  95 extern int selinux_nlmsg_lookup(u16 sclass, u16 nlmsg_type, u32 *perm);
  96 extern struct security_operations *security_ops;
  97
  98 /* SECMARK reference count */
  99 atomic_t selinux_secmark_refcount = ATOMIC_INIT(0);
 100
 101 #ifdef CONFIG_SECURITY_SELINUX_DEVELOP
 102 int selinux_enforcing;
 103
 104 static int __init enforcing_setup(char *str)
 105 {
 106         unsigned long enforcing;
 107         if (!strict_strtoul(str, 0, &enforcing))
 108                 selinux_enforcing = enforcing ? 1 : 0;
 109         return 1;
 110 }
 111 __setup("enforcing=", enforcing_setup);
 112 #endif
 113
 114 #ifdef CONFIG_SECURITY_SELINUX_BOOTPARAM
 115 int selinux_enabled = CONFIG_SECURITY_SELINUX_BOOTPARAM_VALUE;
 116
 117 static int __init selinux_enabled_setup(char *str)
 118 {
 119         unsigned long enabled;
 120         if (!strict_strtoul(str, 0, &enabled))
 121                 selinux_enabled = enabled ? 1 : 0;
 122         return 1;
 123 }
 124 __setup("selinux=", selinux_enabled_setup);
 125 #else
 126 int selinux_enabled = 1;
 127 #endif
 128
 129 static struct kmem_cache *sel_inode_cache;
 130
 131 /**
 132  * selinux_secmark_enabled - Check to see if SECMARK is currently enabled
 133  *
 134  * Description:
 135  * This function checks the SECMARK reference counter to see if any SECMARK
 136  * targets are currently configured, if the reference counter is greater than
 137  * zero SECMARK is considered to be enabled.  Returns true (1) if SECMARK is
 138  * enabled, false (0) if SECMARK is disabled.
 139  *
 140  */
 141 static int selinux_secmark_enabled(void)
 142 {
 143         return (atomic_read(&selinux_secmark_refcount) > 0);
 144 }
 145
 146 /*
 147  * initialise the security for the init task
 148  */
 149 static void cred_init_security(void)
 150 {
 151         struct cred *cred = (struct cred *) current->real_cred;
 152         struct task_security_struct *tsec;
 153
 154         tsec = kzalloc(sizeof(struct task_security_struct), GFP_KERNEL);
 155         if (!tsec)
 156                 panic("SELinux:  Failed to initialize initial task.\n");
 157
 158         tsec->osid = tsec->sid = SECINITSID_KERNEL;
 159         cred->security = tsec;
 160 }
 161
 162 /*
 163  * get the security ID of a set of credentials
 164  */
 165 static inline u32 cred_sid(const struct cred *cred)
 166 {
 167         const struct task_security_struct *tsec;
 168
 169         tsec = cred->security;
 170         return tsec->sid;
 171 }
 172
 173 /*
 174  * get the objective security ID of a task
 175  */
 176 static inline u32 task_sid(const struct task_struct *task)
 177 {
 178         u32 sid;
 179
 180         rcu_read_lock();
 181         sid = cred_sid(__task_cred(task));
 182         rcu_read_unlock();
 183         return sid;
 184 }
 185
 186 /*
 187  * get the subjective security ID of the current task
 188  */
 189 static inline u32 current_sid(void)
 190 {
 191         const struct task_security_struct *tsec = current_security();
 192
 193         return tsec->sid;
 194 }
 195
 196 /* Allocate and free functions for each kind of security blob. */
 197
 198 static int inode_alloc_security(struct inode *inode)
 199 {
 200         struct inode_security_struct *isec;
 201         u32 sid = current_sid();
 202
 203         isec = kmem_cache_zalloc(sel_inode_cache, GFP_NOFS);
 204         if (!isec)
 205                 return -ENOMEM;
 206
 207         mutex_init(&isec->lock);
 208         INIT_LIST_HEAD(&isec->list);
 209         isec->inode = inode;
 210         isec->sid = SECINITSID_UNLABELED;
 211         isec->sclass = SECCLASS_FILE;
 212         isec->task_sid = sid;
 213         inode->i_security = isec;
 214
 215         return 0;
 216 }
 217
 218 static void inode_free_security(struct inode *inode)
 219 {
 220         struct inode_security_struct *isec = inode->i_security;
 221         struct superblock_security_struct *sbsec = inode->i_sb->s_security;
 222
 223         spin_lock(&sbsec->isec_lock);
 224         if (!list_empty(&isec->list))
 225                 list_del_init(&isec->list);
 226         spin_unlock(&sbsec->isec_lock);
 227
 228         inode->i_security = NULL;
 229         kmem_cache_free(sel_inode_cache, isec);
 230 }
 231
 232 static int file_alloc_security(struct file *file)
 233 {
 234         struct file_security_struct *fsec;
 235         u32 sid = current_sid();
 236
 237         fsec = kzalloc(sizeof(struct file_security_struct), GFP_KERNEL);
 238         if (!fsec)
 239                 return -ENOMEM;
 240
 241         fsec->sid = sid;
 242         fsec->fown_sid = sid;
 243         file->f_security = fsec;
 244
 245         return 0;
 246 }
 247
 248 static void file_free_security(struct file *file)
 249 {
 250         struct file_security_struct *fsec = file->f_security;
 251         file->f_security = NULL;
 252         kfree(fsec);
 253 }
 254
 255 static int superblock_alloc_security(struct super_block *sb)
 256 {
 257         struct superblock_security_struct *sbsec;
 258
 259         sbsec = kzalloc(sizeof(struct superblock_security_struct), GFP_KERNEL);
 260         if (!sbsec)
 261                 return -ENOMEM;
 262
 263         mutex_init(&sbsec->lock);
 264         INIT_LIST_HEAD(&sbsec->isec_head);
 265         spin_lock_init(&sbsec->isec_lock);
 266         sbsec->sb = sb;
 267         sbsec->sid = SECINITSID_UNLABELED;
 268         sbsec->def_sid = SECINITSID_FILE;
 269         sbsec->mntpoint_sid = SECINITSID_UNLABELED;
 270         sb->s_security = sbsec;
 271
 272         return 0;
 273 }
 274
 275 static void superblock_free_security(struct super_block *sb)
 276 {
 277         struct superblock_security_struct *sbsec = sb->s_security;
 278         sb->s_security = NULL;
 279         kfree(sbsec);
 280 }
 281
 282 /* The security server must be initialized before
 283    any labeling or access decisions can be provided. */
 284 extern int ss_initialized;
 285
 286 /* The file system's label must be initialized prior to use. */
 287
 288 static const char *labeling_behaviors[6] = {
 289         "uses xattr",
 290         "uses transition SIDs",
 291         "uses task SIDs",
 292         "uses genfs_contexts",
 293         "not configured for labeling",
 294         "uses mountpoint labeling",
 295 };
 296
 297 static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dentry);
 298
 299 static inline int inode_doinit(struct inode *inode)
 300 {
 301         return inode_doinit_with_dentry(inode, NULL);
 302 }
 303
 304 enum {
 305         Opt_error = -1,
 306         Opt_context = 1,
 307         Opt_fscontext = 2,
 308         Opt_defcontext = 3,
 309         Opt_rootcontext = 4,
 310         Opt_labelsupport = 5,
 311 };
 312
 313 static const match_table_t tokens = {
 314         {Opt_context, CONTEXT_STR "%s"},
 315         {Opt_fscontext, FSCONTEXT_STR "%s"},
 316         {Opt_defcontext, DEFCONTEXT_STR "%s"},
 317         {Opt_rootcontext, ROOTCONTEXT_STR "%s"},
 318         {Opt_labelsupport, LABELSUPP_STR},
 319         {Opt_error, NULL},
 320 };
 321
 322 #define SEL_MOUNT_FAIL_MSG "SELinux:  duplicate or incompatible mount options\n"
 323
 324 static int may_context_mount_sb_relabel(u32 sid,
 325                         struct superblock_security_struct *sbsec,
 326                         const struct cred *cred)
 327 {
 328         const struct task_security_struct *tsec = cred->security;
 329         int rc;
 330
 331         rc = avc_has_perm(tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM,
 332                           FILESYSTEM__RELABELFROM, NULL);
 333         if (rc)
 334                 return rc;
 335
 336         rc = avc_has_perm(tsec->sid, sid, SECCLASS_FILESYSTEM,
 337                           FILESYSTEM__RELABELTO, NULL);
 338         return rc;
 339 }
 340
 341 static int may_context_mount_inode_relabel(u32 sid,
 342                         struct superblock_security_struct *sbsec,
 343                         const struct cred *cred)
 344 {
 345         const struct task_security_struct *tsec = cred->security;
 346         int rc;
 347         rc = avc_has_perm(tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM,
 348                           FILESYSTEM__RELABELFROM, NULL);
 349         if (rc)
 350                 return rc;
 351
 352         rc = avc_has_perm(sid, sbsec->sid, SECCLASS_FILESYSTEM,
 353                           FILESYSTEM__ASSOCIATE, NULL);
 354         return rc;
 355 }
 356
 357 static int sb_finish_set_opts(struct super_block *sb)
 358 {
 359         struct superblock_security_struct *sbsec = sb->s_security;
 360         struct dentry *root = sb->s_root;
 361         struct inode *root_inode = root->d_inode;
 362         int rc = 0;
 363
 364         if (sbsec->behavior == SECURITY_FS_USE_XATTR) {
 365                 /* Make sure that the xattr handler exists and that no
 366                    error other than -ENODATA is returned by getxattr on
 367                    the root directory.  -ENODATA is ok, as this may be
 368                    the first boot of the SELinux kernel before we have
 369                    assigned xattr values to the filesystem. */
 370                 if (!root_inode->i_op->getxattr) {
 371                         printk(KERN_WARNING "SELinux: (dev %s, type %s) has no "
 372                                "xattr support\n", sb->s_id, sb->s_type->name);
 373                         rc = -EOPNOTSUPP;
 374                         goto out;
 375                 }
 376                 rc = root_inode->i_op->getxattr(root, XATTR_NAME_SELINUX, NULL, 0);
 377                 if (rc < 0 && rc != -ENODATA) {
 378                         if (rc == -EOPNOTSUPP)
 379                                 printk(KERN_WARNING "SELinux: (dev %s, type "
 380                                        "%s) has no security xattr handler\n",
 381                                        sb->s_id, sb->s_type->name);
 382                         else
 383                                 printk(KERN_WARNING "SELinux: (dev %s, type "
 384                                        "%s) getxattr errno %d\n", sb->s_id,
 385                                        sb->s_type->name, -rc);
 386                         goto out;
 387                 }
 388         }
 389
 390         sbsec->flags |= (SE_SBINITIALIZED | SE_SBLABELSUPP);
 391
 392         if (sbsec->behavior > ARRAY_SIZE(labeling_behaviors))
 393                 printk(KERN_ERR "SELinux: initialized (dev %s, type %s), unknown behavior\n",
 394                        sb->s_id, sb->s_type->name);
 395         else
 396                 printk(KERN_DEBUG "SELinux: initialized (dev %s, type %s), %s\n",
 397                        sb->s_id, sb->s_type->name,
 398                        labeling_behaviors[sbsec->behavior-1]);
 399
 400         if (sbsec->behavior == SECURITY_FS_USE_GENFS ||
 401             sbsec->behavior == SECURITY_FS_USE_MNTPOINT ||
 402             sbsec->behavior == SECURITY_FS_USE_NONE ||
 403             sbsec->behavior > ARRAY_SIZE(labeling_behaviors))
 404                 sbsec->flags &= ~SE_SBLABELSUPP;
 405
 406         /* Special handling for sysfs. Is genfs but also has setxattr handler*/
 407         if (strncmp(sb->s_type->name, "sysfs", sizeof("sysfs")) == 0)
 408                 sbsec->flags |= SE_SBLABELSUPP;
 409
 410         /* Initialize the root inode. */
 411         rc = inode_doinit_with_dentry(root_inode, root);
 412
 413         /* Initialize any other inodes associated with the superblock, e.g.
 414            inodes created prior to initial policy load or inodes created
 415            during get_sb by a pseudo filesystem that directly
 416            populates itself. */
 417         spin_lock(&sbsec->isec_lock);
 418 next_inode:
 419         if (!list_empty(&sbsec->isec_head)) {
 420                 struct inode_security_struct *isec =
 421                                 list_entry(sbsec->isec_head.next,
 422                                            struct inode_security_struct, list);
 423                 struct inode *inode = isec->inode;
 424                 spin_unlock(&sbsec->isec_lock);
 425                 inode = igrab(inode);
 426                 if (inode) {
 427                         if (!IS_PRIVATE(inode))
 428                                 inode_doinit(inode);
 429                         iput(inode);
 430                 }
 431                 spin_lock(&sbsec->isec_lock);
 432                 list_del_init(&isec->list);
 433                 goto next_inode;
 434         }
 435         spin_unlock(&sbsec->isec_lock);
 436 out:
 437         return rc;
 438 }
 439
 440 /*
 441  * This function should allow an FS to ask what it's mount security
 442  * options were so it can use those later for submounts, displaying
 443  * mount options, or whatever.
 444  */
 445 static int selinux_get_mnt_opts(const struct super_block *sb,
 446                                 struct security_mnt_opts *opts)
 447 {
 448         int rc = 0, i;
 449         struct superblock_security_struct *sbsec = sb->s_security;
 450         char *context = NULL;
 451         u32 len;
 452         char tmp;
 453
 454         security_init_mnt_opts(opts);
 455
 456         if (!(sbsec->flags & SE_SBINITIALIZED))
 457                 return -EINVAL;
 458
 459         if (!ss_initialized)
 460                 return -EINVAL;
 461
 462         tmp = sbsec->flags & SE_MNTMASK;
 463         /* count the number of mount options for this sb */
 464         for (i = 0; i < 8; i++) {
 465                 if (tmp & 0x01)
 466                         opts->num_mnt_opts++;
 467                 tmp >>= 1;
 468         }
 469         /* Check if the Label support flag is set */
 470         if (sbsec->flags & SE_SBLABELSUPP)
 471                 opts->num_mnt_opts++;
 472
 473         opts->mnt_opts = kcalloc(opts->num_mnt_opts, sizeof(char *), GFP_ATOMIC);
 474         if (!opts->mnt_opts) {
 475                 rc = -ENOMEM;
 476                 goto out_free;
 477         }
 478
 479         opts->mnt_opts_flags = kcalloc(opts->num_mnt_opts, sizeof(int), GFP_ATOMIC);
 480         if (!opts->mnt_opts_flags) {
 481                 rc = -ENOMEM;
 482                 goto out_free;
 483         }
 484
 485         i = 0;
 486         if (sbsec->flags & FSCONTEXT_MNT) {
 487                 rc = security_sid_to_context(sbsec->sid, &context, &len);
 488                 if (rc)
 489                         goto out_free;
 490                 opts->mnt_opts[i] = context;
 491                 opts->mnt_opts_flags[i++] = FSCONTEXT_MNT;
 492         }
 493         if (sbsec->flags & CONTEXT_MNT) {
 494                 rc = security_sid_to_context(sbsec->mntpoint_sid, &context, &len);
 495                 if (rc)
 496                         goto out_free;
 497                 opts->mnt_opts[i] = context;
 498                 opts->mnt_opts_flags[i++] = CONTEXT_MNT;
 499         }
 500         if (sbsec->flags & DEFCONTEXT_MNT) {
 501                 rc = security_sid_to_context(sbsec->def_sid, &context, &len);
 502                 if (rc)
 503                         goto out_free;
 504                 opts->mnt_opts[i] = context;
 505                 opts->mnt_opts_flags[i++] = DEFCONTEXT_MNT;
 506         }
 507         if (sbsec->flags & ROOTCONTEXT_MNT) {
 508                 struct inode *root = sbsec->sb->s_root->d_inode;
 509                 struct inode_security_struct *isec = root->i_security;
 510
 511                 rc = security_sid_to_context(isec->sid, &context, &len);
 512                 if (rc)
 513                         goto out_free;
 514                 opts->mnt_opts[i] = context;
 515                 opts->mnt_opts_flags[i++] = ROOTCONTEXT_MNT;
 516         }
 517         if (sbsec->flags & SE_SBLABELSUPP) {
 518                 opts->mnt_opts[i] = NULL;
 519                 opts->mnt_opts_flags[i++] = SE_SBLABELSUPP;
 520         }
 521
 522         BUG_ON(i != opts->num_mnt_opts);
 523
 524         return 0;
 525
 526 out_free:
 527         security_free_mnt_opts(opts);
 528         return rc;
 529 }
 530
 531 static int bad_option(struct superblock_security_struct *sbsec, char flag,
 532                       u32 old_sid, u32 new_sid)
 533 {
 534         char mnt_flags = sbsec->flags & SE_MNTMASK;
 535
 536         /* check if the old mount command had the same options */
 537         if (sbsec->flags & SE_SBINITIALIZED)
 538                 if (!(sbsec->flags & flag) ||
 539                     (old_sid != new_sid))
 540                         return 1;
 541
 542         /* check if we were passed the same options twice,
 543          * aka someone passed context=a,context=b
 544          */
 545         if (!(sbsec->flags & SE_SBINITIALIZED))
 546                 if (mnt_flags & flag)
 547                         return 1;
 548         return 0;
 549 }
 550
 551 /*
 552  * Allow filesystems with binary mount data to explicitly set mount point
 553  * labeling information.
 554  */
 555 static int selinux_set_mnt_opts(struct super_block *sb,
 556                                 struct security_mnt_opts *opts)
 557 {
 558         const struct cred *cred = current_cred();
 559         int rc = 0, i;
 560         struct superblock_security_struct *sbsec = sb->s_security;
 561         const char *name = sb->s_type->name;
 562         struct inode *inode = sbsec->sb->s_root->d_inode;
 563         struct inode_security_struct *root_isec = inode->i_security;
 564         u32 fscontext_sid = 0, context_sid = 0, rootcontext_sid = 0;
 565         u32 defcontext_sid = 0;
 566         char **mount_options = opts->mnt_opts;
 567         int *flags = opts->mnt_opts_flags;
 568         int num_opts = opts->num_mnt_opts;
 569
 570         mutex_lock(&sbsec->lock);
 571
 572         if (!ss_initialized) {
 573                 if (!num_opts) {
 574                         /* Defer initialization until selinux_complete_init,
 575                            after the initial policy is loaded and the security
 576                            server is ready to handle calls. */
 577                         goto out;
 578                 }
 579                 rc = -EINVAL;
 580                 printk(KERN_WARNING "SELinux: Unable to set superblock options "
 581                         "before the security server is initialized\n");
 582                 goto out;
 583         }
 584
 585         /*
 586          * Binary mount data FS will come through this function twice.  Once
 587          * from an explicit call and once from the generic calls from the vfs.
 588          * Since the generic VFS calls will not contain any security mount data
 589          * we need to skip the double mount verification.
 590          *
 591          * This does open a hole in which we will not notice if the first
 592          * mount using this sb set explict options and a second mount using
 593          * this sb does not set any security options.  (The first options
 594          * will be used for both mounts)
 595          */
 596         if ((sbsec->flags & SE_SBINITIALIZED) && (sb->s_type->fs_flags & FS_BINARY_MOUNTDATA)
 597             && (num_opts == 0))
 598                 goto out;
 599
 600         /*
 601          * parse the mount options, check if they are valid sids.
 602          * also check if someone is trying to mount the same sb more
 603          * than once with different security options.
 604          */
 605         for (i = 0; i < num_opts; i++) {
 606                 u32 sid;
 607
 608                 if (flags[i] == SE_SBLABELSUPP)
 609                         continue;
 610                 rc = security_context_to_sid(mount_options[i],
 611                                              strlen(mount_options[i]), &sid);
 612                 if (rc) {
 613                         printk(KERN_WARNING "SELinux: security_context_to_sid"
 614                                "(%s) failed for (dev %s, type %s) errno=%d\n",
 615                                mount_options[i], sb->s_id, name, rc);
 616                         goto out;
 617                 }
 618                 switch (flags[i]) {
 619                 case FSCONTEXT_MNT:
 620                         fscontext_sid = sid;
 621
 622                         if (bad_option(sbsec, FSCONTEXT_MNT, sbsec->sid,
 623                                         fscontext_sid))
 624                                 goto out_double_mount;
 625
 626                         sbsec->flags |= FSCONTEXT_MNT;
 627                         break;
 628                 case CONTEXT_MNT:
 629                         context_sid = sid;
 630
 631                         if (bad_option(sbsec, CONTEXT_MNT, sbsec->mntpoint_sid,
 632                                         context_sid))
 633                                 goto out_double_mount;
 634
 635                         sbsec->flags |= CONTEXT_MNT;
 636                         break;
 637                 case ROOTCONTEXT_MNT:
 638                         rootcontext_sid = sid;
 639
 640                         if (bad_option(sbsec, ROOTCONTEXT_MNT, root_isec->sid,
 641                                         rootcontext_sid))
 642                                 goto out_double_mount;
 643
 644                         sbsec->flags |= ROOTCONTEXT_MNT;
 645
 646                         break;
 647                 case DEFCONTEXT_MNT:
 648                         defcontext_sid = sid;
 649
 650                         if (bad_option(sbsec, DEFCONTEXT_MNT, sbsec->def_sid,
 651                                         defcontext_sid))
 652                                 goto out_double_mount;
 653
 654                         sbsec->flags |= DEFCONTEXT_MNT;
 655
 656                         break;
 657                 default:
 658                         rc = -EINVAL;
 659                         goto out;
 660                 }
 661         }
 662
 663         if (sbsec->flags & SE_SBINITIALIZED) {
 664                 /* previously mounted with options, but not on this attempt? */
 665                 if ((sbsec->flags & SE_MNTMASK) && !num_opts)
 666                         goto out_double_mount;
 667                 rc = 0;
 668                 goto out;
 669         }
 670
 671         if (strcmp(sb->s_type->name, "proc") == 0)
 672                 sbsec->flags |= SE_SBPROC;
 673
 674         /* Determine the labeling behavior to use for this filesystem type. */
 675         rc = security_fs_use((sbsec->flags & SE_SBPROC) ? "proc" : sb->s_type->name, &sbsec->behavior, &sbsec->sid);
 676         if (rc) {
 677                 printk(KERN_WARNING "%s: security_fs_use(%s) returned %d\n",
 678                        __func__, sb->s_type->name, rc);
 679                 goto out;
 680         }
 681
 682         /* sets the context of the superblock for the fs being mounted. */
 683         if (fscontext_sid) {
 684                 rc = may_context_mount_sb_relabel(fscontext_sid, sbsec, cred);
 685                 if (rc)
 686                         goto out;
 687
 688                 sbsec->sid = fscontext_sid;
 689         }
 690
 691         /*
 692          * Switch to using mount point labeling behavior.
 693          * sets the label used on all file below the mountpoint, and will set
 694          * the superblock context if not already set.
 695          */
 696         if (context_sid) {
 697                 if (!fscontext_sid) {
 698                         rc = may_context_mount_sb_relabel(context_sid, sbsec,
 699                                                           cred);
 700                         if (rc)
 701                                 goto out;
 702                         sbsec->sid = context_sid;
 703                 } else {
 704                         rc = may_context_mount_inode_relabel(context_sid, sbsec,
 705                                                              cred);
 706                         if (rc)
 707                                 goto out;
 708                 }
 709                 if (!rootcontext_sid)
 710                         rootcontext_sid = context_sid;
 711
 712                 sbsec->mntpoint_sid = context_sid;
 713                 sbsec->behavior = SECURITY_FS_USE_MNTPOINT;
 714         }
 715
 716         if (rootcontext_sid) {
 717                 rc = may_context_mount_inode_relabel(rootcontext_sid, sbsec,
 718                                                      cred);
 719                 if (rc)
 720                         goto out;
 721
 722                 root_isec->sid = rootcontext_sid;
 723                 root_isec->initialized = 1;
 724         }
 725
 726         if (defcontext_sid) {
 727                 if (sbsec->behavior != SECURITY_FS_USE_XATTR) {
 728                         rc = -EINVAL;
 729                         printk(KERN_WARNING "SELinux: defcontext option is "
 730                                "invalid for this filesystem type\n");
 731                         goto out;
 732                 }
 733
 734                 if (defcontext_sid != sbsec->def_sid) {
 735                         rc = may_context_mount_inode_relabel(defcontext_sid,
 736                                                              sbsec, cred);
 737                         if (rc)
 738                                 goto out;
 739                 }
 740
 741                 sbsec->def_sid = defcontext_sid;
 742         }
 743
 744         rc = sb_finish_set_opts(sb);
 745 out:
 746         mutex_unlock(&sbsec->lock);
 747         return rc;
 748 out_double_mount:
 749         rc = -EINVAL;
 750         printk(KERN_WARNING "SELinux: mount invalid.  Same superblock, different "
 751                "security settings for (dev %s, type %s)\n", sb->s_id, name);
 752         goto out;
 753 }
 754
 755 static void selinux_sb_clone_mnt_opts(const struct super_block *oldsb,
 756                                         struct super_block *newsb)
 757 {
 758         const struct superblock_security_struct *oldsbsec = oldsb->s_security;
 759         struct superblock_security_struct *newsbsec = newsb->s_security;
 760
 761         int set_fscontext =     (oldsbsec->flags & FSCONTEXT_MNT);
 762         int set_context =       (oldsbsec->flags & CONTEXT_MNT);
 763         int set_rootcontext =   (oldsbsec->flags & ROOTCONTEXT_MNT);
 764
 765         /*
 766          * if the parent was able to be mounted it clearly had no special lsm
 767          * mount options.  thus we can safely deal with this superblock later
 768          */
 769         if (!ss_initialized)
 770                 return;
 771
 772         /* how can we clone if the old one wasn't set up?? */
 773         BUG_ON(!(oldsbsec->flags & SE_SBINITIALIZED));
 774
 775         /* if fs is reusing a sb, just let its options stand... */
 776         if (newsbsec->flags & SE_SBINITIALIZED)
 777                 return;
 778
 779         mutex_lock(&newsbsec->lock);
 780
 781         newsbsec->flags = oldsbsec->flags;
 782
 783         newsbsec->sid = oldsbsec->sid;
 784         newsbsec->def_sid = oldsbsec->def_sid;
 785         newsbsec->behavior = oldsbsec->behavior;
 786
 787         if (set_context) {
 788                 u32 sid = oldsbsec->mntpoint_sid;
 789
 790                 if (!set_fscontext)
 791                         newsbsec->sid = sid;
 792                 if (!set_rootcontext) {
 793                         struct inode *newinode = newsb->s_root->d_inode;
 794                         struct inode_security_struct *newisec = newinode->i_security;
 795                         newisec->sid = sid;
 796                 }
 797                 newsbsec->mntpoint_sid = sid;
 798         }
 799         if (set_rootcontext) {
 800                 const struct inode *oldinode = oldsb->s_root->d_inode;
 801                 const struct inode_security_struct *oldisec = oldinode->i_security;
 802                 struct inode *newinode = newsb->s_root->d_inode;
 803                 struct inode_security_struct *newisec = newinode->i_security;
 804
 805                 newisec->sid = oldisec->sid;
 806         }
 807
 808         sb_finish_set_opts(newsb);
 809         mutex_unlock(&newsbsec->lock);
 810 }
 811
 812 static int selinux_parse_opts_str(char *options,
 813                                   struct security_mnt_opts *opts)
 814 {
 815         char *p;
 816         char *context = NULL, *defcontext = NULL;
 817         char *fscontext = NULL, *rootcontext = NULL;
 818         int rc, num_mnt_opts = 0;
 819
 820         opts->num_mnt_opts = 0;
 821
 822         /* Standard string-based options. */
 823         while ((p = strsep(&options, "|")) != NULL) {
 824                 int token;
 825                 substring_t args[MAX_OPT_ARGS];
 826
 827                 if (!*p)
 828                         continue;
 829
 830                 token = match_token(p, tokens, args);
 831
 832                 switch (token) {
 833                 case Opt_context:
 834                         if (context || defcontext) {
 835                                 rc = -EINVAL;
 836                                 printk(KERN_WARNING SEL_MOUNT_FAIL_MSG);
 837                                 goto out_err;
 838                         }
 839                         context = match_strdup(&args[0]);
 840                         if (!context) {
 841                                 rc = -ENOMEM;
 842                                 goto out_err;
 843                         }
 844                         break;
 845
 846                 case Opt_fscontext:
 847                         if (fscontext) {
 848                                 rc = -EINVAL;
 849                                 printk(KERN_WARNING SEL_MOUNT_FAIL_MSG);
 850                                 goto out_err;
 851                         }
 852                         fscontext = match_strdup(&args[0]);
 853                         if (!fscontext) {
 854                                 rc = -ENOMEM;
 855                                 goto out_err;
 856                         }
 857                         break;
 858
 859                 case Opt_rootcontext:
 860                         if (rootcontext) {
 861                                 rc = -EINVAL;
 862                                 printk(KERN_WARNING SEL_MOUNT_FAIL_MSG);
 863                                 goto out_err;
 864                         }
 865                         rootcontext = match_strdup(&args[0]);
 866                         if (!rootcontext) {
 867                                 rc = -ENOMEM;
 868                                 goto out_err;
 869                         }
 870                         break;
 871
 872                 case Opt_defcontext:
 873                         if (context || defcontext) {
 874                                 rc = -EINVAL;
 875                                 printk(KERN_WARNING SEL_MOUNT_FAIL_MSG);
 876                                 goto out_err;
 877                         }
 878                         defcontext = match_strdup(&args[0]);
 879                         if (!defcontext) {
 880                                 rc = -ENOMEM;
 881                                 goto out_err;
 882                         }
 883                         break;
 884                 case Opt_labelsupport:
 885                         break;
 886                 default:
 887                         rc = -EINVAL;
 888                         printk(KERN_WARNING "SELinux:  unknown mount option\n");
 889                         goto out_err;
 890
 891                 }
 892         }
 893
 894         rc = -ENOMEM;
 895         opts->mnt_opts = kcalloc(NUM_SEL_MNT_OPTS, sizeof(char *), GFP_ATOMIC);
 896         if (!opts->mnt_opts)
 897                 goto out_err;
 898
 899         opts->mnt_opts_flags = kcalloc(NUM_SEL_MNT_OPTS, sizeof(int), GFP_ATOMIC);
 900         if (!opts->mnt_opts_flags) {
 901                 kfree(opts->mnt_opts);
 902                 goto out_err;
 903         }
 904
 905         if (fscontext) {
 906                 opts->mnt_opts[num_mnt_opts] = fscontext;
 907                 opts->mnt_opts_flags[num_mnt_opts++] = FSCONTEXT_MNT;
 908         }
 909         if (context) {
 910                 opts->mnt_opts[num_mnt_opts] = context;
 911                 opts->mnt_opts_flags[num_mnt_opts++] = CONTEXT_MNT;
 912         }
 913         if (rootcontext) {
 914                 opts->mnt_opts[num_mnt_opts] = rootcontext;
 915                 opts->mnt_opts_flags[num_mnt_opts++] = ROOTCONTEXT_MNT;
 916         }
 917         if (defcontext) {
 918                 opts->mnt_opts[num_mnt_opts] = defcontext;
 919                 opts->mnt_opts_flags[num_mnt_opts++] = DEFCONTEXT_MNT;
 920         }
 921
 922         opts->num_mnt_opts = num_mnt_opts;
 923         return 0;
 924
 925 out_err:
 926         kfree(context);
 927         kfree(defcontext);
 928         kfree(fscontext);
 929         kfree(rootcontext);
 930         return rc;
 931 }
 932 /*
 933  * string mount options parsing and call set the sbsec
 934  */
 935 static int superblock_doinit(struct super_block *sb, void *data)
 936 {
 937         int rc = 0;
 938         char *options = data;
 939         struct security_mnt_opts opts;
 940
 941         security_init_mnt_opts(&opts);
 942
 943         if (!data)
 944                 goto out;
 945
 946         BUG_ON(sb->s_type->fs_flags & FS_BINARY_MOUNTDATA);
 947
 948         rc = selinux_parse_opts_str(options, &opts);
 949         if (rc)
 950                 goto out_err;
 951
 952 out:
 953         rc = selinux_set_mnt_opts(sb, &opts);
 954
 955 out_err:
 956         security_free_mnt_opts(&opts);
 957         return rc;
 958 }
 959
 960 static void selinux_write_opts(struct seq_file *m,
 961                                struct security_mnt_opts *opts)
 962 {
 963         int i;
 964         char *prefix;
 965
 966         for (i = 0; i < opts->num_mnt_opts; i++) {
 967                 char *has_comma;
 968
 969                 if (opts->mnt_opts[i])
 970                         has_comma = strchr(opts->mnt_opts[i], ',');
 971                 else
 972                         has_comma = NULL;
 973
 974                 switch (opts->mnt_opts_flags[i]) {
 975                 case CONTEXT_MNT:
 976                         prefix = CONTEXT_STR;
 977                         break;
 978                 case FSCONTEXT_MNT:
 979                         prefix = FSCONTEXT_STR;
 980                         break;
 981                 case ROOTCONTEXT_MNT:
 982                         prefix = ROOTCONTEXT_STR;
 983                         break;
 984                 case DEFCONTEXT_MNT:
 985                         prefix = DEFCONTEXT_STR;
 986                         break;
 987                 case SE_SBLABELSUPP:
 988                         seq_putc(m, ',');
 989                         seq_puts(m, LABELSUPP_STR);
 990                         continue;
 991                 default:
 992                         BUG();
 993                 };
 994                 /* we need a comma before each option */
 995                 seq_putc(m, ',');
 996                 seq_puts(m, prefix);
 997                 if (has_comma)
 998                         seq_putc(m, '\"');
 999                 seq_puts(m, opts->mnt_opts[i]);
1000                 if (has_comma)
1001                         seq_putc(m, '\"');
1002         }
1003 }
1004
1005 static int selinux_sb_show_options(struct seq_file *m, struct super_block *sb)
1006 {
1007         struct security_mnt_opts opts;
1008         int rc;
1009
1010         rc = selinux_get_mnt_opts(sb, &opts);
1011         if (rc) {
1012                 /* before policy load we may get EINVAL, don't show anything */
1013                 if (rc == -EINVAL)
1014                         rc = 0;
1015                 return rc;
1016         }
1017
1018         selinux_write_opts(m, &opts);
1019
1020         security_free_mnt_opts(&opts);
1021
1022         return rc;
1023 }
1024
1025 static inline u16 inode_mode_to_security_class(umode_t mode)
1026 {
1027         switch (mode & S_IFMT) {
1028         case S_IFSOCK:
1029                 return SECCLASS_SOCK_FILE;
1030         case S_IFLNK:
1031                 return SECCLASS_LNK_FILE;
1032         case S_IFREG:
1033                 return SECCLASS_FILE;
1034         case S_IFBLK:
1035                 return SECCLASS_BLK_FILE;
1036         case S_IFDIR:
1037                 return SECCLASS_DIR;
1038         case S_IFCHR:
1039                 return SECCLASS_CHR_FILE;
1040         case S_IFIFO:
1041                 return SECCLASS_FIFO_FILE;
1042
1043         }
1044
1045         return SECCLASS_FILE;
1046 }
1047
1048 static inline int default_protocol_stream(int protocol)
1049 {
1050         return (protocol == IPPROTO_IP || protocol == IPPROTO_TCP);
1051 }
1052
1053 static inline int default_protocol_dgram(int protocol)
1054 {
1055         return (protocol == IPPROTO_IP || protocol == IPPROTO_UDP);
1056 }
1057
1058 static inline u16 socket_type_to_security_class(int family, int type, int protocol)
1059 {
1060         switch (family) {
1061         case PF_UNIX:
1062                 switch (type) {
1063                 case SOCK_STREAM:
1064                 case SOCK_SEQPACKET:
1065                         return SECCLASS_UNIX_STREAM_SOCKET;
1066                 case SOCK_DGRAM:
1067                         return SECCLASS_UNIX_DGRAM_SOCKET;
1068                 }
1069                 break;
1070         case PF_INET:
1071         case PF_INET6:
1072                 switch (type) {
1073                 case SOCK_STREAM:
1074                         if (default_protocol_stream(protocol))
1075                                 return SECCLASS_TCP_SOCKET;
1076                         else
1077                                 return SECCLASS_RAWIP_SOCKET;
1078                 case SOCK_DGRAM:
1079                         if (default_protocol_dgram(protocol))
1080                                 return SECCLASS_UDP_SOCKET;
1081                         else
1082                                 return SECCLASS_RAWIP_SOCKET;
1083                 case SOCK_DCCP:
1084                         return SECCLASS_DCCP_SOCKET;
1085                 default:
1086                         return SECCLASS_RAWIP_SOCKET;
1087                 }
1088                 break;
1089         case PF_NETLINK:
1090                 switch (protocol) {
1091                 case NETLINK_ROUTE:
1092                         return SECCLASS_NETLINK_ROUTE_SOCKET;
1093                 case NETLINK_FIREWALL:
1094                         return SECCLASS_NETLINK_FIREWALL_SOCKET;
1095                 case NETLINK_INET_DIAG:
1096                         return SECCLASS_NETLINK_TCPDIAG_SOCKET;
1097                 case NETLINK_NFLOG:
1098                         return SECCLASS_NETLINK_NFLOG_SOCKET;
1099                 case NETLINK_XFRM:
1100                         return SECCLASS_NETLINK_XFRM_SOCKET;
1101                 case NETLINK_SELINUX:
1102                         return SECCLASS_NETLINK_SELINUX_SOCKET;
1103                 case NETLINK_AUDIT:
1104                         return SECCLASS_NETLINK_AUDIT_SOCKET;
1105                 case NETLINK_IP6_FW:
1106                         return SECCLASS_NETLINK_IP6FW_SOCKET;
1107                 case NETLINK_DNRTMSG:
1108                         return SECCLASS_NETLINK_DNRT_SOCKET;
1109                 case NETLINK_KOBJECT_UEVENT:
1110                         return SECCLASS_NETLINK_KOBJECT_UEVENT_SOCKET;
1111                 default:
1112                         return SECCLASS_NETLINK_SOCKET;
1113                 }
1114         case PF_PACKET:
1115                 return SECCLASS_PACKET_SOCKET;
1116         case PF_KEY:
1117                 return SECCLASS_KEY_SOCKET;
1118         case PF_APPLETALK:
1119                 return SECCLASS_APPLETALK_SOCKET;
1120         }
1121
1122         return SECCLASS_SOCKET;
1123 }
1124
1125 #ifdef CONFIG_PROC_FS
1126 static int selinux_proc_get_sid(struct proc_dir_entry *de,
1127                                 u16 tclass,
1128                                 u32 *sid)
1129 {
1130         int buflen, rc;
1131         char *buffer, *path, *end;
1132
1133         buffer = (char *)__get_free_page(GFP_KERNEL);
1134         if (!buffer)
1135                 return -ENOMEM;
1136
1137         buflen = PAGE_SIZE;
1138         end = buffer+buflen;
1139         *--end = '\0';
1140         buflen--;
1141         path = end-1;
1142         *path = '/';
1143         while (de && de != de->parent) {
1144                 buflen -= de->namelen + 1;
1145                 if (buflen < 0)
1146                         break;
1147                 end -= de->namelen;
1148                 memcpy(end, de->name, de->namelen);
1149                 *--end = '/';
1150                 path = end;
1151                 de = de->parent;
1152         }
1153         rc = security_genfs_sid("proc", path, tclass, sid);
1154         free_page((unsigned long)buffer);
1155         return rc;
1156 }
1157 #else
1158 static int selinux_proc_get_sid(struct proc_dir_entry *de,
1159                                 u16 tclass,
1160                                 u32 *sid)
1161 {
1162         return -EINVAL;
1163 }
1164 #endif
1165
1166 /* The inode's security attributes must be initialized before first use. */
1167 static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dentry)
1168 {
1169         struct superblock_security_struct *sbsec = NULL;
1170         struct inode_security_struct *isec = inode->i_security;
1171         u32 sid;
1172         struct dentry *dentry;
1173 #define INITCONTEXTLEN 255
1174         char *context = NULL;
1175         unsigned len = 0;
1176         int rc = 0;
1177
1178         if (isec->initialized)
1179                 goto out;
1180
1181         mutex_lock(&isec->lock);
1182         if (isec->initialized)
1183                 goto out_unlock;
1184
1185         sbsec = inode->i_sb->s_security;
1186         if (!(sbsec->flags & SE_SBINITIALIZED)) {
1187                 /* Defer initialization until selinux_complete_init,
1188                    after the initial policy is loaded and the security
1189                    server is ready to handle calls. */
1190                 spin_lock(&sbsec->isec_lock);
1191                 if (list_empty(&isec->list))
1192                         list_add(&isec->list, &sbsec->isec_head);
1193                 spin_unlock(&sbsec->isec_lock);
1194                 goto out_unlock;
1195         }
1196
1197         switch (sbsec->behavior) {
1198         case SECURITY_FS_USE_XATTR:
1199                 if (!inode->i_op->getxattr) {
1200                         isec->sid = sbsec->def_sid;
1201                         break;
1202                 }
1203
1204                 /* Need a dentry, since the xattr API requires one.
1205                    Life would be simpler if we could just pass the inode. */
1206                 if (opt_dentry) {
1207                         /* Called from d_instantiate or d_splice_alias. */
1208                         dentry = dget(opt_dentry);
1209                 } else {
1210                         /* Called from selinux_complete_init, try to find a dentry. */
1211                         dentry = d_find_alias(inode);
1212                 }
1213                 if (!dentry) {
1214                         /*
1215                          * this is can be hit on boot when a file is accessed
1216                          * before the policy is loaded.  When we load policy we
1217                          * may find inodes that have no dentry on the
1218                          * sbsec->isec_head list.  No reason to complain as these
1219                          * will get fixed up the next time we go through
1220                          * inode_doinit with a dentry, before these inodes could
1221                          * be used again by userspace.
1222                          */
1223                         goto out_unlock;
1224                 }
1225
1226                 len = INITCONTEXTLEN;
1227                 context = kmalloc(len+1, GFP_NOFS);
1228                 if (!context) {
1229                         rc = -ENOMEM;
1230                         dput(dentry);
1231                         goto out_unlock;
1232                 }
1233                 context[len] = '\0';
1234                 rc = inode->i_op->getxattr(dentry, XATTR_NAME_SELINUX,
1235                                            context, len);
1236                 if (rc == -ERANGE) {
1237                         kfree(context);
1238
1239                         /* Need a larger buffer.  Query for the right size. */
1240                         rc = inode->i_op->getxattr(dentry, XATTR_NAME_SELINUX,
1241                                                    NULL, 0);
1242                         if (rc < 0) {
1243                                 dput(dentry);
1244                                 goto out_unlock;
1245                         }
1246                         len = rc;
1247                         context = kmalloc(len+1, GFP_NOFS);
1248                         if (!context) {
1249                                 rc = -ENOMEM;
1250                                 dput(dentry);
1251                                 goto out_unlock;
1252                         }
1253                         context[len] = '\0';
1254                         rc = inode->i_op->getxattr(dentry,
1255                                                    XATTR_NAME_SELINUX,
1256                                                    context, len);
1257                 }
1258                 dput(dentry);
1259                 if (rc < 0) {
1260                         if (rc != -ENODATA) {
1261                                 printk(KERN_WARNING "SELinux: %s:  getxattr returned "
1262                                        "%d for dev=%s ino=%ld\n", __func__,
1263                                        -rc, inode->i_sb->s_id, inode->i_ino);
1264                                 kfree(context);
1265                                 goto out_unlock;
1266                         }
1267                         /* Map ENODATA to the default file SID */
1268                         sid = sbsec->def_sid;
1269                         rc = 0;
1270                 } else {
1271                         rc = security_context_to_sid_default(context, rc, &sid,
1272                                                              sbsec->def_sid,
1273                                                              GFP_NOFS);
1274                         if (rc) {
1275                                 char *dev = inode->i_sb->s_id;
1276                                 unsigned long ino = inode->i_ino;
1277
1278                                 if (rc == -EINVAL) {
1279                                         if (printk_ratelimit())
1280                                                 printk(KERN_NOTICE "SELinux: inode=%lu on dev=%s was found to have an invalid "
1281                                                         "context=%s.  This indicates you may need to relabel the inode or the "
1282                                                         "filesystem in question.\n", ino, dev, context);
1283                                 } else {
1284                                         printk(KERN_WARNING "SELinux: %s:  context_to_sid(%s) "
1285                                                "returned %d for dev=%s ino=%ld\n",
1286                                                __func__, context, -rc, dev, ino);
1287                                 }
1288                                 kfree(context);
1289                                 /* Leave with the unlabeled SID */
1290                                 rc = 0;
1291                                 break;
1292                         }
1293                 }
1294                 kfree(context);
1295                 isec->sid = sid;
1296                 break;
1297         case SECURITY_FS_USE_TASK:
1298                 isec->sid = isec->task_sid;
1299                 break;
1300         case SECURITY_FS_USE_TRANS:
1301                 /* Default to the fs SID. */
1302                 isec->sid = sbsec->sid;
1303
1304                 /* Try to obtain a transition SID. */
1305                 isec->sclass = inode_mode_to_security_class(inode->i_mode);
1306                 rc = security_transition_sid(isec->task_sid,
1307                                              sbsec->sid,
1308                                              isec->sclass,
1309                                              &sid);
1310                 if (rc)
1311                         goto out_unlock;
1312                 isec->sid = sid;
1313                 break;
1314         case SECURITY_FS_USE_MNTPOINT:
1315                 isec->sid = sbsec->mntpoint_sid;
1316                 break;
1317         default:
1318                 /* Default to the fs superblock SID. */
1319                 isec->sid = sbsec->sid;
1320
1321                 if ((sbsec->flags & SE_SBPROC) && !S_ISLNK(inode->i_mode)) {
1322                         struct proc_inode *proci = PROC_I(inode);
1323                         if (proci->pde) {
1324                                 isec->sclass = inode_mode_to_security_class(inode->i_mode);
1325                                 rc = selinux_proc_get_sid(proci->pde,
1326                                                           isec->sclass,
1327                                                           &sid);
1328                                 if (rc)
1329                                         goto out_unlock;
1330                                 isec->sid = sid;
1331                         }
1332                 }
1333                 break;
1334         }
1335
1336         isec->initialized = 1;
1337
1338 out_unlock:
1339         mutex_unlock(&isec->lock);
1340 out:
1341         if (isec->sclass == SECCLASS_FILE)
1342                 isec->sclass = inode_mode_to_security_class(inode->i_mode);
1343         return rc;
1344 }
1345
1346 /* Convert a Linux signal to an access vector. */
1347 static inline u32 signal_to_av(int sig)
1348 {
1349         u32 perm = 0;
1350
1351         switch (sig) {
1352         case SIGCHLD:
1353                 /* Commonly granted from child to parent. */
1354                 perm = PROCESS__SIGCHLD;
1355                 break;
1356         case SIGKILL:
1357                 /* Cannot be caught or ignored */
1358                 perm = PROCESS__SIGKILL;
1359                 break;
1360         case SIGSTOP:
1361                 /* Cannot be caught or ignored */
1362                 perm = PROCESS__SIGSTOP;
1363                 break;
1364         default:
1365                 /* All other signals. */
1366                 perm = PROCESS__SIGNAL;
1367                 break;
1368         }
1369
1370         return perm;
1371 }
1372
1373 /*
1374  * Check permission between a pair of credentials
1375  * fork check, ptrace check, etc.
1376  */
1377 static int cred_has_perm(const struct cred *actor,
1378                          const struct cred *target,
1379                          u32 perms)
1380 {
1381         u32 asid = cred_sid(actor), tsid = cred_sid(target);
1382
1383         return avc_has_perm(asid, tsid, SECCLASS_PROCESS, perms, NULL);
1384 }
1385
1386 /*
1387  * Check permission between a pair of tasks, e.g. signal checks,
1388  * fork check, ptrace check, etc.
1389  * tsk1 is the actor and tsk2 is the target
1390  * - this uses the default subjective creds of tsk1
1391  */
1392 static int task_has_perm(const struct task_struct *tsk1,
1393                          const struct task_struct *tsk2,
1394                          u32 perms)
1395 {
1396         const struct task_security_struct *__tsec1, *__tsec2;
1397         u32 sid1, sid2;
1398
1399         rcu_read_lock();
1400         __tsec1 = __task_cred(tsk1)->security;  sid1 = __tsec1->sid;
1401         __tsec2 = __task_cred(tsk2)->security;  sid2 = __tsec2->sid;
1402         rcu_read_unlock();
1403         return avc_has_perm(sid1, sid2, SECCLASS_PROCESS, perms, NULL);
1404 }
1405
1406 /*
1407  * Check permission between current and another task, e.g. signal checks,
1408  * fork check, ptrace check, etc.
1409  * current is the actor and tsk2 is the target
1410  * - this uses current's subjective creds
1411  */
1412 static int current_has_perm(const struct task_struct *tsk,
1413                             u32 perms)
1414 {
1415         u32 sid, tsid;
1416
1417         sid = current_sid();
1418         tsid = task_sid(tsk);
1419         return avc_has_perm(sid, tsid, SECCLASS_PROCESS, perms, NULL);
1420 }
1421
1422 #if CAP_LAST_CAP > 63
1423 #error Fix SELinux to handle capabilities > 63.
1424 #endif
1425
1426 /* Check whether a task is allowed to use a capability. */
1427 static int task_has_capability(struct task_struct *tsk,
1428                                const struct cred *cred,
1429                                int cap, int audit)
1430 {
1431         struct common_audit_data ad;
1432         struct av_decision avd;
1433         u16 sclass;
1434         u32 sid = cred_sid(cred);
1435         u32 av = CAP_TO_MASK(cap);
1436         int rc;
1437
1438         COMMON_AUDIT_DATA_INIT(&ad, CAP);
1439         ad.tsk = tsk;
1440         ad.u.cap = cap;
1441
1442         switch (CAP_TO_INDEX(cap)) {
1443         case 0:
1444                 sclass = SECCLASS_CAPABILITY;
1445                 break;
1446         case 1:
1447                 sclass = SECCLASS_CAPABILITY2;
1448                 break;
1449         default:
1450                 printk(KERN_ERR
1451                        "SELinux:  out of range capability %d\n", cap);
1452                 BUG();
1453         }
1454
1455         rc = avc_has_perm_noaudit(sid, sid, sclass, av, 0, &avd);
1456         if (audit == SECURITY_CAP_AUDIT)
1457                 avc_audit(sid, sid, sclass, av, &avd, rc, &ad);
1458         return rc;
1459 }
1460
1461 /* Check whether a task is allowed to use a system operation. */
1462 static int task_has_system(struct task_struct *tsk,
1463                            u32 perms)
1464 {
1465         u32 sid = task_sid(tsk);
1466
1467         return avc_has_perm(sid, SECINITSID_KERNEL,
1468                             SECCLASS_SYSTEM, perms, NULL);
1469 }
1470
1471 /* Check whether a task has a particular permission to an inode.
1472    The 'adp' parameter is optional and allows other audit
1473    data to be passed (e.g. the dentry). */
1474 static int inode_has_perm(const struct cred *cred,
1475                           struct inode *inode,
1476                           u32 perms,
1477                           struct common_audit_data *adp)
1478 {
1479         struct inode_security_struct *isec;
1480         struct common_audit_data ad;
1481         u32 sid;
1482
1483         validate_creds(cred);
1484
1485         if (unlikely(IS_PRIVATE(inode)))
1486                 return 0;
1487
1488         sid = cred_sid(cred);
1489         isec = inode->i_security;
1490
1491         if (!adp) {
1492                 adp = &ad;
1493                 COMMON_AUDIT_DATA_INIT(&ad, FS);
1494                 ad.u.fs.inode = inode;
1495         }
1496
1497         return avc_has_perm(sid, isec->sid, isec->sclass, perms, adp);
1498 }
1499
1500 /* Same as inode_has_perm, but pass explicit audit data containing
1501    the dentry to help the auditing code to more easily generate the
1502    pathname if needed. */
1503 static inline int dentry_has_perm(const struct cred *cred,
1504                                   struct vfsmount *mnt,
1505                                   struct dentry *dentry,
1506                                   u32 av)
1507 {
1508         struct inode *inode = dentry->d_inode;
1509         struct common_audit_data ad;
1510
1511         COMMON_AUDIT_DATA_INIT(&ad, FS);
1512         ad.u.fs.path.mnt = mnt;
1513         ad.u.fs.path.dentry = dentry;
1514         return inode_has_perm(cred, inode, av, &ad);
1515 }
1516
1517 /* Check whether a task can use an open file descriptor to
1518    access an inode in a given way.  Check access to the
1519    descriptor itself, and then use dentry_has_perm to
1520    check a particular permission to the file.
1521    Access to the descriptor is implicitly granted if it
1522    has the same SID as the process.  If av is zero, then
1523    access to the file is not checked, e.g. for cases
1524    where only the descriptor is affected like seek. */
1525 static int file_has_perm(const struct cred *cred,
1526                          struct file *file,
1527                          u32 av)
1528 {
1529         struct file_security_struct *fsec = file->f_security;
1530         struct inode *inode = file->f_path.dentry->d_inode;
1531         struct common_audit_data ad;
1532         u32 sid = cred_sid(cred);
1533         int rc;
1534
1535         COMMON_AUDIT_DATA_INIT(&ad, FS);
1536         ad.u.fs.path = file->f_path;
1537
1538         if (sid != fsec->sid) {
1539                 rc = avc_has_perm(sid, fsec->sid,
1540                                   SECCLASS_FD,
1541                                   FD__USE,
1542                                   &ad);
1543                 if (rc)
1544                         goto out;
1545         }
1546
1547         /* av is zero if only checking access to the descriptor. */
1548         rc = 0;
1549         if (av)
1550                 rc = inode_has_perm(cred, inode, av, &ad);
1551
1552 out:
1553         return rc;
1554 }
1555
1556 /* Check whether a task can create a file. */
1557 static int may_create(struct inode *dir,
1558                       struct dentry *dentry,
1559                       u16 tclass)
1560 {
1561         const struct task_security_struct *tsec = current_security();
1562         struct inode_security_struct *dsec;
1563         struct superblock_security_struct *sbsec;
1564         u32 sid, newsid;
1565         struct common_audit_data ad;
1566         int rc;
1567
1568         dsec = dir->i_security;
1569         sbsec = dir->i_sb->s_security;
1570
1571         sid = tsec->sid;
1572         newsid = tsec->create_sid;
1573
1574         COMMON_AUDIT_DATA_INIT(&ad, FS);
1575         ad.u.fs.path.dentry = dentry;
1576
1577         rc = avc_has_perm(sid, dsec->sid, SECCLASS_DIR,
1578                           DIR__ADD_NAME | DIR__SEARCH,
1579                           &ad);
1580         if (rc)
1581                 return rc;
1582
1583         if (!newsid || !(sbsec->flags & SE_SBLABELSUPP)) {
1584                 rc = security_transition_sid(sid, dsec->sid, tclass, &newsid);
1585                 if (rc)
1586                         return rc;
1587         }
1588
1589         rc = avc_has_perm(sid, newsid, tclass, FILE__CREATE, &ad);
1590         if (rc)
1591                 return rc;
1592
1593         return avc_has_perm(newsid, sbsec->sid,
1594                             SECCLASS_FILESYSTEM,
1595                             FILESYSTEM__ASSOCIATE, &ad);
1596 }
1597
1598 /* Check whether a task can create a key. */
1599 static int may_create_key(u32 ksid,
1600                           struct task_struct *ctx)
1601 {
1602         u32 sid = task_sid(ctx);
1603
1604         return avc_has_perm(sid, ksid, SECCLASS_KEY, KEY__CREATE, NULL);
1605 }
1606
1607 #define MAY_LINK        0
1608 #define MAY_UNLINK      1
1609 #define MAY_RMDIR       2
1610
1611 /* Check whether a task can link, unlink, or rmdir a file/directory. */
1612 static int may_link(struct inode *dir,
1613                     struct dentry *dentry,
1614                     int kind)
1615
1616 {
1617         struct inode_security_struct *dsec, *isec;
1618         struct common_audit_data ad;
1619         u32 sid = current_sid();
1620         u32 av;
1621         int rc;
1622
1623         dsec = dir->i_security;
1624         isec = dentry->d_inode->i_security;
1625
1626         COMMON_AUDIT_DATA_INIT(&ad, FS);
1627         ad.u.fs.path.dentry = dentry;
1628
1629         av = DIR__SEARCH;
1630         av |= (kind ? DIR__REMOVE_NAME : DIR__ADD_NAME);
1631         rc = avc_has_perm(sid, dsec->sid, SECCLASS_DIR, av, &ad);
1632         if (rc)
1633                 return rc;
1634
1635         switch (kind) {
1636         case MAY_LINK:
1637                 av = FILE__LINK;
1638                 break;
1639         case MAY_UNLINK:
1640                 av = FILE__UNLINK;
1641                 break;
1642         case MAY_RMDIR:
1643                 av = DIR__RMDIR;
1644                 break;
1645         default:
1646                 printk(KERN_WARNING "SELinux: %s:  unrecognized kind %d\n",
1647                         __func__, kind);
1648                 return 0;
1649         }
1650
1651         rc = avc_has_perm(sid, isec->sid, isec->sclass, av, &ad);
1652         return rc;
1653 }
1654
1655 static inline int may_rename(struct inode *old_dir,
1656                              struct dentry *old_dentry,
1657                              struct inode *new_dir,
1658                              struct dentry *new_dentry)
1659 {
1660         struct inode_security_struct *old_dsec, *new_dsec, *old_isec, *new_isec;
1661         struct common_audit_data ad;
1662         u32 sid = current_sid();
1663         u32 av;
1664         int old_is_dir, new_is_dir;
1665         int rc;
1666
1667         old_dsec = old_dir->i_security;
1668         old_isec = old_dentry->d_inode->i_security;
1669         old_is_dir = S_ISDIR(old_dentry->d_inode->i_mode);
1670         new_dsec = new_dir->i_security;
1671
1672         COMMON_AUDIT_DATA_INIT(&ad, FS);
1673
1674         ad.u.fs.path.dentry = old_dentry;
1675         rc = avc_has_perm(sid, old_dsec->sid, SECCLASS_DIR,
1676                           DIR__REMOVE_NAME | DIR__SEARCH, &ad);
1677         if (rc)
1678                 return rc;
1679         rc = avc_has_perm(sid, old_isec->sid,
1680                           old_isec->sclass, FILE__RENAME, &ad);
1681         if (rc)
1682                 return rc;
1683         if (old_is_dir && new_dir != old_dir) {
1684                 rc = avc_has_perm(sid, old_isec->sid,
1685                                   old_isec->sclass, DIR__REPARENT, &ad);
1686                 if (rc)
1687                         return rc;
1688         }
1689
1690         ad.u.fs.path.dentry = new_dentry;
1691         av = DIR__ADD_NAME | DIR__SEARCH;
1692         if (new_dentry->d_inode)
1693                 av |= DIR__REMOVE_NAME;
1694         rc = avc_has_perm(sid, new_dsec->sid, SECCLASS_DIR, av, &ad);
1695         if (rc)
1696                 return rc;
1697         if (new_dentry->d_inode) {
1698                 new_isec = new_dentry->d_inode->i_security;
1699                 new_is_dir = S_ISDIR(new_dentry->d_inode->i_mode);
1700                 rc = avc_has_perm(sid, new_isec->sid,
1701                                   new_isec->sclass,
1702                                   (new_is_dir ? DIR__RMDIR : FILE__UNLINK), &ad);
1703                 if (rc)
1704                         return rc;
1705         }
1706
1707         return 0;
1708 }
1709
1710 /* Check whether a task can perform a filesystem operation. */
1711 static int superblock_has_perm(const struct cred *cred,
1712                                struct super_block *sb,
1713                                u32 perms,
1714                                struct common_audit_data *ad)
1715 {
1716         struct superblock_security_struct *sbsec;
1717         u32 sid = cred_sid(cred);
1718
1719         sbsec = sb->s_security;
1720         return avc_has_perm(sid, sbsec->sid, SECCLASS_FILESYSTEM, perms, ad);
1721 }
1722
1723 /* Convert a Linux mode and permission mask to an access vector. */
1724 static inline u32 file_mask_to_av(int mode, int mask)
1725 {
1726         u32 av = 0;
1727
1728         if ((mode & S_IFMT) != S_IFDIR) {
1729                 if (mask & MAY_EXEC)
1730                         av |= FILE__EXECUTE;
1731                 if (mask & MAY_READ)
1732                         av |= FILE__READ;
1733
1734                 if (mask & MAY_APPEND)
1735                         av |= FILE__APPEND;
1736                 else if (mask & MAY_WRITE)
1737                         av |= FILE__WRITE;
1738
1739         } else {
1740                 if (mask & MAY_EXEC)
1741                         av |= DIR__SEARCH;
1742                 if (mask & MAY_WRITE)
1743                         av |= DIR__WRITE;
1744                 if (mask & MAY_READ)
1745                         av |= DIR__READ;
1746         }
1747
1748         return av;
1749 }
1750
1751 /* Convert a Linux file to an access vector. */
1752 static inline u32 file_to_av(struct file *file)
1753 {
1754         u32 av = 0;
1755
1756         if (file->f_mode & FMODE_READ)
1757                 av |= FILE__READ;
1758         if (file->f_mode & FMODE_WRITE) {
1759                 if (file->f_flags & O_APPEND)
1760                         av |= FILE__APPEND;
1761                 else
1762                         av |= FILE__WRITE;
1763         }
1764         if (!av) {
1765                 /*
1766                  * Special file opened with flags 3 for ioctl-only use.
1767                  */
1768                 av = FILE__IOCTL;
1769         }
1770
1771         return av;
1772 }
1773
1774 /*
1775  * Convert a file to an access vector and include the correct open
1776  * open permission.
1777  */
1778 static inline u32 open_file_to_av(struct file *file)
1779 {
1780         u32 av = file_to_av(file);
1781
1782         if (selinux_policycap_openperm) {
1783                 mode_t mode = file->f_path.dentry->d_inode->i_mode;
1784                 /*
1785                  * lnk files and socks do not really have an 'open'
1786                  */
1787                 if (S_ISREG(mode))
1788                         av |= FILE__OPEN;
1789                 else if (S_ISCHR(mode))
1790                         av |= CHR_FILE__OPEN;
1791                 else if (S_ISBLK(mode))
1792                         av |= BLK_FILE__OPEN;
1793                 else if (S_ISFIFO(mode))
1794                         av |= FIFO_FILE__OPEN;
1795                 else if (S_ISDIR(mode))
1796                         av |= DIR__OPEN;
1797                 else if (S_ISSOCK(mode))
1798                         av |= SOCK_FILE__OPEN;
1799                 else
1800                         printk(KERN_ERR "SELinux: WARNING: inside %s with "
1801                                 "unknown mode:%o\n", __func__, mode);
1802         }
1803         return av;
1804 }
1805
1806 /* Hook functions begin here. */
1807
1808 static int selinux_ptrace_access_check(struct task_struct *child,
1809                                      unsigned int mode)
1810 {
1811         int rc;
1812
1813         rc = cap_ptrace_access_check(child, mode);
1814         if (rc)
1815                 return rc;
1816
1817         if (mode == PTRACE_MODE_READ) {
1818                 u32 sid = current_sid();
1819                 u32 csid = task_sid(child);
1820                 return avc_has_perm(sid, csid, SECCLASS_FILE, FILE__READ, NULL);
1821         }
1822
1823         return current_has_perm(child, PROCESS__PTRACE);
1824 }
1825
1826 static int selinux_ptrace_traceme(struct task_struct *parent)
1827 {
1828         int rc;
1829
1830         rc = cap_ptrace_traceme(parent);
1831         if (rc)
1832                 return rc;
1833
1834         return task_has_perm(parent, current, PROCESS__PTRACE);
1835 }
1836
1837 static int selinux_capget(struct task_struct *target, kernel_cap_t *effective,
1838                           kernel_cap_t *inheritable, kernel_cap_t *permitted)
1839 {
1840         int error;
1841
1842         error = current_has_perm(target, PROCESS__GETCAP);
1843         if (error)
1844                 return error;
1845
1846         return cap_capget(target, effective, inheritable, permitted);
1847 }
1848
1849 static int selinux_capset(struct cred *new, const struct cred *old,
1850                           const kernel_cap_t *effective,
1851                           const kernel_cap_t *inheritable,
1852                           const kernel_cap_t *permitted)
1853 {
1854         int error;
1855
1856         error = cap_capset(new, old,
1857                                       effective, inheritable, permitted);
1858         if (error)
1859                 return error;
1860
1861         return cred_has_perm(old, new, PROCESS__SETCAP);
1862 }
1863
1864 /*
1865  * (This comment used to live with the selinux_task_setuid hook,
1866  * which was removed).
1867  *
1868  * Since setuid only affects the current process, and since the SELinux
1869  * controls are not based on the Linux identity attributes, SELinux does not
1870  * need to control this operation.  However, SELinux does control the use of
1871  * the CAP_SETUID and CAP_SETGID capabilities using the capable hook.
1872  */
1873
1874 static int selinux_capable(struct task_struct *tsk, const struct cred *cred,
1875                            int cap, int audit)
1876 {
1877         int rc;
1878
1879         rc = cap_capable(tsk, cred, cap, audit);
1880         if (rc)
1881                 return rc;
1882
1883         return task_has_capability(tsk, cred, cap, audit);
1884 }
1885
1886 static int selinux_sysctl_get_sid(ctl_table *table, u16 tclass, u32 *sid)
1887 {
1888         int buflen, rc;
1889         char *buffer, *path, *end;
1890
1891         rc = -ENOMEM;
1892         buffer = (char *)__get_free_page(GFP_KERNEL);
1893         if (!buffer)
1894                 goto out;
1895
1896         buflen = PAGE_SIZE;
1897         end = buffer+buflen;
1898         *--end = '\0';
1899         buflen--;
1900         path = end-1;
1901         *path = '/';
1902         while (table) {
1903                 const char *name = table->procname;
1904                 size_t namelen = strlen(name);
1905                 buflen -= namelen + 1;
1906                 if (buflen < 0)
1907                         goto out_free;
1908                 end -= namelen;
1909                 memcpy(end, name, namelen);
1910                 *--end = '/';
1911                 path = end;
1912                 table = table->parent;
1913         }
1914         buflen -= 4;
1915         if (buflen < 0)
1916                 goto out_free;
1917         end -= 4;
1918         memcpy(end, "/sys", 4);
1919         path = end;
1920         rc = security_genfs_sid("proc", path, tclass, sid);
1921 out_free:
1922         free_page((unsigned long)buffer);
1923 out:
1924         return rc;
1925 }
1926
1927 static int selinux_sysctl(ctl_table *table, int op)
1928 {
1929         int error = 0;
1930         u32 av;
1931         u32 tsid, sid;
1932         int rc;
1933
1934         sid = current_sid();
1935
1936         rc = selinux_sysctl_get_sid(table, (op == 0001) ?
1937                                     SECCLASS_DIR : SECCLASS_FILE, &tsid);
1938         if (rc) {
1939                 /* Default to the well-defined sysctl SID. */
1940                 tsid = SECINITSID_SYSCTL;
1941         }
1942
1943         /* The op values are "defined" in sysctl.c, thereby creating
1944          * a bad coupling between this module and sysctl.c */
1945         if (op == 001) {
1946                 error = avc_has_perm(sid, tsid,
1947                                      SECCLASS_DIR, DIR__SEARCH, NULL);
1948         } else {
1949                 av = 0;
1950                 if (op & 004)
1951                         av |= FILE__READ;
1952                 if (op & 002)
1953                         av |= FILE__WRITE;
1954                 if (av)
1955                         error = avc_has_perm(sid, tsid,
1956                                              SECCLASS_FILE, av, NULL);
1957         }
1958
1959         return error;
1960 }
1961
1962 static int selinux_quotactl(int cmds, int type, int id, struct super_block *sb)
1963 {
1964         const struct cred *cred = current_cred();
1965         int rc = 0;
1966
1967         if (!sb)
1968                 return 0;
1969
1970         switch (cmds) {
1971         case Q_SYNC:
1972         case Q_QUOTAON:
1973         case Q_QUOTAOFF:
1974         case Q_SETINFO:
1975         case Q_SETQUOTA:
1976                 rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAMOD, NULL);
1977                 break;
1978         case Q_GETFMT:
1979         case Q_GETINFO:
1980         case Q_GETQUOTA:
1981                 rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAGET, NULL);
1982                 break;
1983         default:
1984                 rc = 0;  /* let the kernel handle invalid cmds */
1985                 break;
1986         }
1987         return rc;
1988 }
1989
1990 static int selinux_quota_on(struct dentry *dentry)
1991 {
1992         const struct cred *cred = current_cred();
1993
1994         return dentry_has_perm(cred, NULL, dentry, FILE__QUOTAON);
1995 }
1996
1997 static int selinux_syslog(int type, bool from_file)
1998 {
1999         int rc;
2000
2001         rc = cap_syslog(type, from_file);
2002         if (rc)
2003                 return rc;
2004
2005         switch (type) {
2006         case SYSLOG_ACTION_READ_ALL:    /* Read last kernel messages */
2007         case SYSLOG_ACTION_SIZE_BUFFER: /* Return size of the log buffer */
2008                 rc = task_has_system(current, SYSTEM__SYSLOG_READ);
2009                 break;
2010         case SYSLOG_ACTION_CONSOLE_OFF: /* Disable logging to console */
2011         case SYSLOG_ACTION_CONSOLE_ON:  /* Enable logging to console */
2012         /* Set level of messages printed to console */
2013         case SYSLOG_ACTION_CONSOLE_LEVEL:
2014                 rc = task_has_system(current, SYSTEM__SYSLOG_CONSOLE);
2015                 break;
2016         case SYSLOG_ACTION_CLOSE:       /* Close log */
2017         case SYSLOG_ACTION_OPEN:        /* Open log */
2018         case SYSLOG_ACTION_READ:        /* Read from log */
2019         case SYSLOG_ACTION_READ_CLEAR:  /* Read/clear last kernel messages */
2020         case SYSLOG_ACTION_CLEAR:       /* Clear ring buffer */
2021         default:
2022                 rc = task_has_system(current, SYSTEM__SYSLOG_MOD);
2023                 break;
2024         }
2025         return rc;
2026 }
2027
2028 /*
2029  * Check that a process has enough memory to allocate a new virtual
2030  * mapping. 0 means there is enough memory for the allocation to
2031  * succeed and -ENOMEM implies there is not.
2032  *
2033  * Do not audit the selinux permission check, as this is applied to all
2034  * processes that allocate mappings.
2035  */
2036 static int selinux_vm_enough_memory(struct mm_struct *mm, long pages)
2037 {
2038         int rc, cap_sys_admin = 0;
2039
2040         rc = selinux_capable(current, current_cred(), CAP_SYS_ADMIN,
2041                              SECURITY_CAP_NOAUDIT);
2042         if (rc == 0)
2043                 cap_sys_admin = 1;
2044
2045         return __vm_enough_memory(mm, pages, cap_sys_admin);
2046 }
2047
2048 /* binprm security operations */
2049
2050 static int selinux_bprm_set_creds(struct linux_binprm *bprm)
2051 {
2052         const struct task_security_struct *old_tsec;
2053         struct task_security_struct *new_tsec;
2054         struct inode_security_struct *isec;
2055         struct common_audit_data ad;
2056         struct inode *inode = bprm->file->f_path.dentry->d_inode;
2057         int rc;
2058
2059         rc = cap_bprm_set_creds(bprm);
2060         if (rc)
2061                 return rc;
2062
2063         /* SELinux context only depends on initial program or script and not
2064          * the script interpreter */
2065         if (bprm->cred_prepared)
2066                 return 0;
2067
2068         old_tsec = current_security();
2069         new_tsec = bprm->cred->security;
2070         isec = inode->i_security;
2071
2072         /* Default to the current task SID. */
2073         new_tsec->sid = old_tsec->sid;
2074         new_tsec->osid = old_tsec->sid;
2075
2076         /* Reset fs, key, and sock SIDs on execve. */
2077         new_tsec->create_sid = 0;
2078         new_tsec->keycreate_sid = 0;
2079         new_tsec->sockcreate_sid = 0;
2080
2081         if (old_tsec->exec_sid) {
2082                 new_tsec->sid = old_tsec->exec_sid;
2083                 /* Reset exec SID on execve. */
2084                 new_tsec->exec_sid = 0;
2085         } else {
2086                 /* Check for a default transition on this program. */
2087                 rc = security_transition_sid(old_tsec->sid, isec->sid,
2088                                              SECCLASS_PROCESS, &new_tsec->sid);
2089                 if (rc)
2090                         return rc;
2091         }
2092
2093         COMMON_AUDIT_DATA_INIT(&ad, FS);
2094         ad.u.fs.path = bprm->file->f_path;
2095
2096         if (bprm->file->f_path.mnt->mnt_flags & MNT_NOSUID)
2097                 new_tsec->sid = old_tsec->sid;
2098
2099         if (new_tsec->sid == old_tsec->sid) {
2100                 rc = avc_has_perm(old_tsec->sid, isec->sid,
2101                                   SECCLASS_FILE, FILE__EXECUTE_NO_TRANS, &ad);
2102                 if (rc)
2103                         return rc;
2104         } else {
2105                 /* Check permissions for the transition. */
2106                 rc = avc_has_perm(old_tsec->sid, new_tsec->sid,
2107                                   SECCLASS_PROCESS, PROCESS__TRANSITION, &ad);
2108                 if (rc)
2109                         return rc;
2110
2111                 rc = avc_has_perm(new_tsec->sid, isec->sid,
2112                                   SECCLASS_FILE, FILE__ENTRYPOINT, &ad);
2113                 if (rc)
2114                         return rc;
2115
2116                 /* Check for shared state */
2117                 if (bprm->unsafe & LSM_UNSAFE_SHARE) {
2118                         rc = avc_has_perm(old_tsec->sid, new_tsec->sid,
2119                                           SECCLASS_PROCESS, PROCESS__SHARE,
2120                                           NULL);
2121                         if (rc)
2122                                 return -EPERM;
2123                 }
2124
2125                 /* Make sure that anyone attempting to ptrace over a task that
2126                  * changes its SID has the appropriate permit */
2127                 if (bprm->unsafe &
2128                     (LSM_UNSAFE_PTRACE | LSM_UNSAFE_PTRACE_CAP)) {
2129                         struct task_struct *tracer;
2130                         struct task_security_struct *sec;
2131                         u32 ptsid = 0;
2132
2133                         rcu_read_lock();
2134                         tracer = tracehook_tracer_task(current);
2135                         if (likely(tracer != NULL)) {
2136                                 sec = __task_cred(tracer)->security;
2137                                 ptsid = sec->sid;
2138                         }
2139                         rcu_read_unlock();
2140
2141                         if (ptsid != 0) {
2142                                 rc = avc_has_perm(ptsid, new_tsec->sid,
2143                                                   SECCLASS_PROCESS,
2144                                                   PROCESS__PTRACE, NULL);
2145                                 if (rc)
2146                                         return -EPERM;
2147                         }
2148                 }
2149
2150                 /* Clear any possibly unsafe personality bits on exec: */
2151                 bprm->per_clear |= PER_CLEAR_ON_SETID;
2152         }
2153
2154         return 0;
2155 }
2156
2157 static int selinux_bprm_secureexec(struct linux_binprm *bprm)
2158 {
2159         const struct task_security_struct *tsec = current_security();
2160         u32 sid, osid;
2161         int atsecure = 0;
2162
2163         sid = tsec->sid;
2164         osid = tsec->osid;
2165
2166         if (osid != sid) {
2167                 /* Enable secure mode for SIDs transitions unless
2168                    the noatsecure permission is granted between
2169                    the two SIDs, i.e. ahp returns 0. */
2170                 atsecure = avc_has_perm(osid, sid,
2171                                         SECCLASS_PROCESS,
2172                                         PROCESS__NOATSECURE, NULL);
2173         }
2174
2175         return (atsecure || cap_bprm_secureexec(bprm));
2176 }
2177
2178 extern struct vfsmount *selinuxfs_mount;
2179 extern struct dentry *selinux_null;
2180
2181 /* Derived from fs/exec.c:flush_old_files. */
2182 static inline void flush_unauthorized_files(const struct cred *cred,
2183                                             struct files_struct *files)
2184 {
2185         struct common_audit_data ad;
2186         struct file *file, *devnull = NULL;
2187         struct tty_struct *tty;
2188         struct fdtable *fdt;
2189         long j = -1;
2190         int drop_tty = 0;
2191
2192         tty = get_current_tty();
2193         if (tty) {
2194                 file_list_lock();
2195                 if (!list_empty(&tty->tty_files)) {
2196                         struct inode *inode;
2197
2198                         /* Revalidate access to controlling tty.
2199                            Use inode_has_perm on the tty inode directly rather
2200                            than using file_has_perm, as this particular open
2201                            file may belong to another process and we are only
2202                            interested in the inode-based check here. */
2203                         file = list_first_entry(&tty->tty_files, struct file, f_u.fu_list);
2204                         inode = file->f_path.dentry->d_inode;
2205                         if (inode_has_perm(cred, inode,
2206                                            FILE__READ | FILE__WRITE, NULL)) {
2207                                 drop_tty = 1;
2208                         }
2209                 }
2210                 file_list_unlock();
2211                 tty_kref_put(tty);
2212         }
2213         /* Reset controlling tty. */
2214         if (drop_tty)
2215                 no_tty();
2216
2217         /* Revalidate access to inherited open files. */
2218
2219         COMMON_AUDIT_DATA_INIT(&ad, FS);
2220
2221         spin_lock(&files->file_lock);
2222         for (;;) {
2223                 unsigned long set, i;
2224                 int fd;
2225
2226                 j++;
2227                 i = j * __NFDBITS;
2228                 fdt = files_fdtable(files);
2229                 if (i >= fdt->max_fds)
2230                         break;
2231                 set = fdt->open_fds->fds_bits[j];
2232                 if (!set)
2233                         continue;
2234                 spin_unlock(&files->file_lock);
2235                 for ( ; set ; i++, set >>= 1) {
2236                         if (set & 1) {
2237                                 file = fget(i);
2238                                 if (!file)
2239                                         continue;
2240                                 if (file_has_perm(cred,
2241                                                   file,
2242                                                   file_to_av(file))) {
2243                                         sys_close(i);
2244                                         fd = get_unused_fd();
2245                                         if (fd != i) {
2246                                                 if (fd >= 0)
2247                                                         put_unused_fd(fd);
2248                                                 fput(file);
2249                                                 continue;
2250                                         }
2251                                         if (devnull) {
2252                                                 get_file(devnull);
2253                                         } else {
2254                                                 devnull = dentry_open(
2255                                                         dget(selinux_null),
2256                                                         mntget(selinuxfs_mount),
2257                                                         O_RDWR, cred);
2258                                                 if (IS_ERR(devnull)) {
2259                                                         devnull = NULL;
2260                                                         put_unused_fd(fd);
2261                                                         fput(file);
2262                                                         continue;
2263                                                 }
2264                                         }
2265                                         fd_install(fd, devnull);
2266                                 }
2267                                 fput(file);
2268                         }
2269                 }
2270                 spin_lock(&files->file_lock);
2271
2272         }
2273         spin_unlock(&files->file_lock);
2274 }
2275
2276 /*
2277  * Prepare a process for imminent new credential changes due to exec
2278  */
2279 static void selinux_bprm_committing_creds(struct linux_binprm *bprm)
2280 {
2281         struct task_security_struct *new_tsec;
2282         struct rlimit *rlim, *initrlim;
2283         int rc, i;
2284
2285         new_tsec = bprm->cred->security;
2286         if (new_tsec->sid == new_tsec->osid)
2287                 return;
2288
2289         /* Close files for which the new task SID is not authorized. */
2290         flush_unauthorized_files(bprm->cred, current->files);
2291
2292         /* Always clear parent death signal on SID transitions. */
2293         current->pdeath_signal = 0;
2294
2295         /* Check whether the new SID can inherit resource limits from the old
2296          * SID.  If not, reset all soft limits to the lower of the current
2297          * task's hard limit and the init task's soft limit.
2298          *
2299          * Note that the setting of hard limits (even to lower them) can be
2300          * controlled by the setrlimit check.  The inclusion of the init task's
2301          * soft limit into the computation is to avoid resetting soft limits
2302          * higher than the default soft limit for cases where the default is
2303          * lower than the hard limit, e.g. RLIMIT_CORE or RLIMIT_STACK.
2304          */
2305         rc = avc_has_perm(new_tsec->osid, new_tsec->sid, SECCLASS_PROCESS,
2306                           PROCESS__RLIMITINH, NULL);
2307         if (rc) {
2308                 for (i = 0; i < RLIM_NLIMITS; i++) {
2309                         rlim = current->signal->rlim + i;
2310                         initrlim = init_task.signal->rlim + i;
2311                         rlim->rlim_cur = min(rlim->rlim_max, initrlim->rlim_cur);
2312                 }
2313                 update_rlimit_cpu(current->signal->rlim[RLIMIT_CPU].rlim_cur);
2314         }
2315 }
2316
2317 /*
2318  * Clean up the process immediately after the installation of new credentials
2319  * due to exec
2320  */
2321 static void selinux_bprm_committed_creds(struct linux_binprm *bprm)
2322 {
2323         const struct task_security_struct *tsec = current_security();
2324         struct itimerval itimer;
2325         u32 osid, sid;
2326         int rc, i;
2327
2328         osid = tsec->osid;
2329         sid = tsec->sid;
2330
2331         if (sid == osid)
2332                 return;
2333
2334         /* Check whether the new SID can inherit signal state from the old SID.
2335          * If not, clear itimers to avoid subsequent signal generation and
2336          * flush and unblock signals.
2337          *
2338          * This must occur _after_ the task SID has been updated so that any
2339          * kill done after the flush will be checked against the new SID.
2340          */
2341         rc = avc_has_perm(osid, sid, SECCLASS_PROCESS, PROCESS__SIGINH, NULL);
2342         if (rc) {
2343                 memset(&itimer, 0, sizeof itimer);
2344                 for (i = 0; i < 3; i++)
2345                         do_setitimer(i, &itimer, NULL);
2346                 spin_lock_irq(&current->sighand->siglock);
2347                 if (!(current->signal->flags & SIGNAL_GROUP_EXIT)) {
2348                         __flush_signals(current);
2349                         flush_signal_handlers(current, 1);
2350                         sigemptyset(&current->blocked);
2351                 }
2352                 spin_unlock_irq(&current->sighand->siglock);
2353         }
2354
2355         /* Wake up the parent if it is waiting so that it can recheck
2356          * wait permission to the new task SID. */
2357         read_lock(&tasklist_lock);
2358         __wake_up_parent(current, current->real_parent);
2359         read_unlock(&tasklist_lock);
2360 }
2361
2362 /* superblock security operations */
2363
2364 static int selinux_sb_alloc_security(struct super_block *sb)
2365 {
2366         return superblock_alloc_security(sb);
2367 }
2368
2369 static void selinux_sb_free_security(struct super_block *sb)
2370 {
2371         superblock_free_security(sb);
2372 }
2373
2374 static inline int match_prefix(char *prefix, int plen, char *option, int olen)
2375 {
2376         if (plen > olen)
2377                 return 0;
2378
2379         return !memcmp(prefix, option, plen);
2380 }
2381
2382 static inline int selinux_option(char *option, int len)
2383 {
2384         return (match_prefix(CONTEXT_STR, sizeof(CONTEXT_STR)-1, option, len) ||
2385                 match_prefix(FSCONTEXT_STR, sizeof(FSCONTEXT_STR)-1, option, len) ||
2386                 match_prefix(DEFCONTEXT_STR, sizeof(DEFCONTEXT_STR)-1, option, len) ||
2387                 match_prefix(ROOTCONTEXT_STR, sizeof(ROOTCONTEXT_STR)-1, option, len) ||
2388                 match_prefix(LABELSUPP_STR, sizeof(LABELSUPP_STR)-1, option, len));
2389 }
2390
2391 static inline void take_option(char **to, char *from, int *first, int len)
2392 {
2393         if (!*first) {
2394                 **to = ',';
2395                 *to += 1;
2396         } else
2397                 *first = 0;
2398         memcpy(*to, from, len);
2399         *to += len;
2400 }
2401
2402 static inline void take_selinux_option(char **to, char *from, int *first,
2403                                        int len)
2404 {
2405         int current_size = 0;
2406
2407         if (!*first) {
2408                 **to = '|';
2409                 *to += 1;
2410         } else
2411                 *first = 0;
2412
2413         while (current_size < len) {
2414                 if (*from != '"') {
2415                         **to = *from;
2416                         *to += 1;
2417                 }
2418                 from += 1;
2419                 current_size += 1;
2420         }
2421 }
2422
2423 static int selinux_sb_copy_data(char *orig, char *copy)
2424 {
2425         int fnosec, fsec, rc = 0;
2426         char *in_save, *in_curr, *in_end;
2427         char *sec_curr, *nosec_save, *nosec;
2428         int open_quote = 0;
2429
2430         in_curr = orig;
2431         sec_curr = copy;
2432
2433         nosec = (char *)get_zeroed_page(GFP_KERNEL);
2434         if (!nosec) {
2435                 rc = -ENOMEM;
2436                 goto out;
2437         }
2438
2439         nosec_save = nosec;
2440         fnosec = fsec = 1;
2441         in_save = in_end = orig;
2442
2443         do {
2444                 if (*in_end == '"')
2445                         open_quote = !open_quote;
2446                 if ((*in_end == ',' && open_quote == 0) ||
2447                                 *in_end == '\0') {
2448                         int len = in_end - in_curr;
2449
2450                         if (selinux_option(in_curr, len))
2451                                 take_selinux_option(&sec_curr, in_curr, &fsec, len);
2452                         else
2453                                 take_option(&nosec, in_curr, &fnosec, len);
2454
2455                         in_curr = in_end + 1;
2456                 }
2457         } while (*in_end++);
2458
2459         strcpy(in_save, nosec_save);
2460         free_page((unsigned long)nosec_save);
2461 out:
2462         return rc;
2463 }
2464
2465 static int selinux_sb_kern_mount(struct super_block *sb, int flags, void *data)
2466 {
2467         const struct cred *cred = current_cred();
2468         struct common_audit_data ad;
2469         int rc;
2470
2471         rc = superblock_doinit(sb, data);
2472         if (rc)
2473                 return rc;
2474
2475         /* Allow all mounts performed by the kernel */
2476         if (flags & MS_KERNMOUNT)
2477                 return 0;
2478
2479         COMMON_AUDIT_DATA_INIT(&ad, FS);
2480         ad.u.fs.path.dentry = sb->s_root;
2481         return superblock_has_perm(cred, sb, FILESYSTEM__MOUNT, &ad);
2482 }
2483
2484 static int selinux_sb_statfs(struct dentry *dentry)
2485 {
2486         const struct cred *cred = current_cred();
2487         struct common_audit_data ad;
2488
2489         COMMON_AUDIT_DATA_INIT(&ad, FS);
2490         ad.u.fs.path.dentry = dentry->d_sb->s_root;
2491         return superblock_has_perm(cred, dentry->d_sb, FILESYSTEM__GETATTR, &ad);
2492 }
2493
2494 static int selinux_mount(char *dev_name,
2495                          struct path *path,
2496                          char *type,
2497                          unsigned long flags,
2498                          void *data)
2499 {
2500         const struct cred *cred = current_cred();
2501
2502         if (flags & MS_REMOUNT)
2503                 return superblock_has_perm(cred, path->mnt->mnt_sb,
2504                                            FILESYSTEM__REMOUNT, NULL);
2505         else
2506                 return dentry_has_perm(cred, path->mnt, path->dentry,
2507                                        FILE__MOUNTON);
2508 }
2509
2510 static int selinux_umount(struct vfsmount *mnt, int flags)
2511 {
2512         const struct cred *cred = current_cred();
2513
2514         return superblock_has_perm(cred, mnt->mnt_sb,
2515                                    FILESYSTEM__UNMOUNT, NULL);
2516 }
2517
2518 /* inode security operations */
2519
2520 static int selinux_inode_alloc_security(struct inode *inode)
2521 {
2522         return inode_alloc_security(inode);
2523 }
2524
2525 static void selinux_inode_free_security(struct inode *inode)
2526 {
2527         inode_free_security(inode);
2528 }
2529
2530 static int selinux_inode_init_security(struct inode *inode, struct inode *dir,
2531                                        char **name, void **value,
2532                                        size_t *len)
2533 {
2534         const struct task_security_struct *tsec = current_security();
2535         struct inode_security_struct *dsec;
2536         struct superblock_security_struct *sbsec;
2537         u32 sid, newsid, clen;
2538         int rc;
2539         char *namep = NULL, *context;
2540
2541         dsec = dir->i_security;
2542         sbsec = dir->i_sb->s_security;
2543
2544         sid = tsec->sid;
2545         newsid = tsec->create_sid;
2546
2547         if (!newsid || !(sbsec->flags & SE_SBLABELSUPP)) {
2548                 rc = security_transition_sid(sid, dsec->sid,
2549                                              inode_mode_to_security_class(inode->i_mode),
2550                                              &newsid);
2551                 if (rc) {
2552                         printk(KERN_WARNING "%s:  "
2553                                "security_transition_sid failed, rc=%d (dev=%s "
2554                                "ino=%ld)\n",
2555                                __func__,
2556                                -rc, inode->i_sb->s_id, inode->i_ino);
2557                         return rc;
2558                 }
2559         }
2560
2561         /* Possibly defer initialization to selinux_complete_init. */
2562         if (sbsec->flags & SE_SBINITIALIZED) {
2563                 struct inode_security_struct *isec = inode->i_security;
2564                 isec->sclass = inode_mode_to_security_class(inode->i_mode);
2565                 isec->sid = newsid;
2566                 isec->initialized = 1;
2567         }
2568
2569         if (!ss_initialized || !(sbsec->flags & SE_SBLABELSUPP))
2570                 return -EOPNOTSUPP;
2571
2572         if (name) {
2573                 namep = kstrdup(XATTR_SELINUX_SUFFIX, GFP_NOFS);
2574                 if (!namep)
2575                         return -ENOMEM;
2576                 *name = namep;
2577         }
2578
2579         if (value && len) {
2580                 rc = security_sid_to_context_force(newsid, &context, &clen);
2581                 if (rc) {
2582                         kfree(namep);
2583                         return rc;
2584                 }
2585                 *value = context;
2586                 *len = clen;
2587         }
2588
2589         return 0;
2590 }
2591
2592 static int selinux_inode_create(struct inode *dir, struct dentry *dentry, int mask)
2593 {
2594         return may_create(dir, dentry, SECCLASS_FILE);
2595 }
2596
2597 static int selinux_inode_link(struct dentry *old_dentry, struct inode *dir, struct dentry *new_dentry)
2598 {
2599         return may_link(dir, old_dentry, MAY_LINK);
2600 }
2601
2602 static int selinux_inode_unlink(struct inode *dir, struct dentry *dentry)
2603 {
2604         return may_link(dir, dentry, MAY_UNLINK);
2605 }
2606
2607 static int selinux_inode_symlink(struct inode *dir, struct dentry *dentry, const char *name)
2608 {
2609         return may_create(dir, dentry, SECCLASS_LNK_FILE);
2610 }
2611
2612 static int selinux_inode_mkdir(struct inode *dir, struct dentry *dentry, int mask)
2613 {
2614         return may_create(dir, dentry, SECCLASS_DIR);
2615 }
2616
2617 static int selinux_inode_rmdir(struct inode *dir, struct dentry *dentry)
2618 {
2619         return may_link(dir, dentry, MAY_RMDIR);
2620 }
2621
2622 static int selinux_inode_mknod(struct inode *dir, struct dentry *dentry, int mode, dev_t dev)
2623 {
2624         return may_create(dir, dentry, inode_mode_to_security_class(mode));
2625 }
2626
2627 static int selinux_inode_rename(struct inode *old_inode, struct dentry *old_dentry,
2628                                 struct inode *new_inode, struct dentry *new_dentry)
2629 {
2630         return may_rename(old_inode, old_dentry, new_inode, new_dentry);
2631 }
2632
2633 static int selinux_inode_readlink(struct dentry *dentry)
2634 {
2635         const struct cred *cred = current_cred();
2636
2637         return dentry_has_perm(cred, NULL, dentry, FILE__READ);
2638 }
2639
2640 static int selinux_inode_follow_link(struct dentry *dentry, struct nameidata *nameidata)
2641 {
2642         const struct cred *cred = current_cred();
2643
2644         return dentry_has_perm(cred, NULL, dentry, FILE__READ);
2645 }
2646
2647 static int selinux_inode_permission(struct inode *inode, int mask)
2648 {
2649         const struct cred *cred = current_cred();
2650
2651         if (!mask) {
2652                 /* No permission to check.  Existence test. */
2653                 return 0;
2654         }
2655
2656         return inode_has_perm(cred, inode,
2657                               file_mask_to_av(inode->i_mode, mask), NULL);
2658 }
2659
2660 static int selinux_inode_setattr(struct dentry *dentry, struct iattr *iattr)
2661 {
2662         const struct cred *cred = current_cred();
2663         unsigned int ia_valid = iattr->ia_valid;
2664
2665         /* ATTR_FORCE is just used for ATTR_KILL_S[UG]ID. */
2666         if (ia_valid & ATTR_FORCE) {
2667                 ia_valid &= ~(ATTR_KILL_SUID | ATTR_KILL_SGID | ATTR_MODE |
2668                               ATTR_FORCE);
2669                 if (!ia_valid)
2670                         return 0;
2671         }
2672
2673         if (ia_valid & (ATTR_MODE | ATTR_UID | ATTR_GID |
2674                         ATTR_ATIME_SET | ATTR_MTIME_SET | ATTR_TIMES_SET))
2675                 return dentry_has_perm(cred, NULL, dentry, FILE__SETATTR);
2676
2677         return dentry_has_perm(cred, NULL, dentry, FILE__WRITE);
2678 }
2679
2680 static int selinux_inode_getattr(struct vfsmount *mnt, struct dentry *dentry)
2681 {
2682         const struct cred *cred = current_cred();
2683
2684         return dentry_has_perm(cred, mnt, dentry, FILE__GETATTR);
2685 }
2686
2687 static int selinux_inode_setotherxattr(struct dentry *dentry, const char *name)
2688 {
2689         const struct cred *cred = current_cred();
2690
2691         if (!strncmp(name, XATTR_SECURITY_PREFIX,
2692                      sizeof XATTR_SECURITY_PREFIX - 1)) {
2693                 if (!strcmp(name, XATTR_NAME_CAPS)) {
2694                         if (!capable(CAP_SETFCAP))
2695                                 return -EPERM;
2696                 } else if (!capable(CAP_SYS_ADMIN)) {
2697                         /* A different attribute in the security namespace.
2698                            Restrict to administrator. */
2699                         return -EPERM;
2700                 }
2701         }
2702
2703         /* Not an attribute we recognize, so just check the
2704            ordinary setattr permission. */
2705         return dentry_has_perm(cred, NULL, dentry, FILE__SETATTR);
2706 }
2707
2708 static int selinux_inode_setxattr(struct dentry *dentry, const char *name,
2709                                   const void *value, size_t size, int flags)
2710 {
2711         struct inode *inode = dentry->d_inode;
2712         struct inode_security_struct *isec = inode->i_security;
2713         struct superblock_security_struct *sbsec;
2714         struct common_audit_data ad;
2715         u32 newsid, sid = current_sid();
2716         int rc = 0;
2717
2718         if (strcmp(name, XATTR_NAME_SELINUX))
2719                 return selinux_inode_setotherxattr(dentry, name);
2720
2721         sbsec = inode->i_sb->s_security;
2722         if (!(sbsec->flags & SE_SBLABELSUPP))
2723                 return -EOPNOTSUPP;
2724
2725         if (!is_owner_or_cap(inode))
2726                 return -EPERM;
2727
2728         COMMON_AUDIT_DATA_INIT(&ad, FS);
2729         ad.u.fs.path.dentry = dentry;
2730
2731         rc = avc_has_perm(sid, isec->sid, isec->sclass,
2732                           FILE__RELABELFROM, &ad);
2733         if (rc)
2734                 return rc;
2735
2736         rc = security_context_to_sid(value, size, &newsid);
2737         if (rc == -EINVAL) {
2738                 if (!capable(CAP_MAC_ADMIN))
2739                         return rc;
2740                 rc = security_context_to_sid_force(value, size, &newsid);
2741         }
2742         if (rc)
2743                 return rc;
2744
2745         rc = avc_has_perm(sid, newsid, isec->sclass,
2746                           FILE__RELABELTO, &ad);
2747         if (rc)
2748                 return rc;
2749
2750         rc = security_validate_transition(isec->sid, newsid, sid,
2751                                           isec->sclass);
2752         if (rc)
2753                 return rc;
2754
2755         return avc_has_perm(newsid,
2756                             sbsec->sid,
2757                             SECCLASS_FILESYSTEM,
2758                             FILESYSTEM__ASSOCIATE,
2759                             &ad);
2760 }
2761
2762 static void selinux_inode_post_setxattr(struct dentry *dentry, const char *name,
2763                                         const void *value, size_t size,
2764                                         int flags)
2765 {
2766         struct inode *inode = dentry->d_inode;
2767         struct inode_security_struct *isec = inode->i_security;
2768         u32 newsid;
2769         int rc;
2770
2771         if (strcmp(name, XATTR_NAME_SELINUX)) {
2772                 /* Not an attribute we recognize, so nothing to do. */
2773                 return;
2774         }
2775
2776         rc = security_context_to_sid_force(value, size, &newsid);
2777         if (rc) {
2778                 printk(KERN_ERR "SELinux:  unable to map context to SID"
2779                        "for (%s, %lu), rc=%d\n",
2780                        inode->i_sb->s_id, inode->i_ino, -rc);
2781                 return;
2782         }
2783
2784         isec->sid = newsid;
2785         return;
2786 }
2787
2788 static int selinux_inode_getxattr(struct dentry *dentry, const char *name)
2789 {
2790         const struct cred *cred = current_cred();
2791
2792         return dentry_has_perm(cred, NULL, dentry, FILE__GETATTR);
2793 }
2794
2795 static int selinux_inode_listxattr(struct dentry *dentry)
2796 {
2797         const struct cred *cred = current_cred();
2798
2799         return dentry_has_perm(cred, NULL, dentry, FILE__GETATTR);
2800 }
2801
2802 static int selinux_inode_removexattr(struct dentry *dentry, const char *name)
2803 {
2804         if (strcmp(name, XATTR_NAME_SELINUX))
2805                 return selinux_inode_setotherxattr(dentry, name);
2806
2807         /* No one is allowed to remove a SELinux security label.
2808            You can change the label, but all data must be labeled. */
2809         return -EACCES;
2810 }
2811
2812 /*
2813  * Copy the inode security context value to the user.
2814  *
2815  * Permission check is handled by selinux_inode_getxattr hook.
2816  */
2817 static int selinux_inode_getsecurity(const struct inode *inode, const char *name, void **buffer, bool alloc)
2818 {
2819         u32 size;
2820         int error;
2821         char *context = NULL;
2822         struct inode_security_struct *isec = inode->i_security;
2823
2824         if (strcmp(name, XATTR_SELINUX_SUFFIX))
2825                 return -EOPNOTSUPP;
2826
2827         /*
2828          * If the caller has CAP_MAC_ADMIN, then get the raw context
2829          * value even if it is not defined by current policy; otherwise,
2830          * use the in-core value under current policy.
2831          * Use the non-auditing forms of the permission checks since
2832          * getxattr may be called by unprivileged processes commonly
2833          * and lack of permission just means that we fall back to the
2834          * in-core context value, not a denial.
2835          */
2836         error = selinux_capable(current, current_cred(), CAP_MAC_ADMIN,
2837                                 SECURITY_CAP_NOAUDIT);
2838         if (!error)
2839                 error = security_sid_to_context_force(isec->sid, &context,
2840                                                       &size);
2841         else
2842                 error = security_sid_to_context(isec->sid, &context, &size);
2843         if (error)
2844                 return error;
2845         error = size;
2846         if (alloc) {
2847                 *buffer = context;
2848                 goto out_nofree;
2849         }
2850         kfree(context);
2851 out_nofree:
2852         return error;
2853 }
2854
2855 static int selinux_inode_setsecurity(struct inode *inode, const char *name,
2856                                      const void *value, size_t size, int flags)
2857 {
2858         struct inode_security_struct *isec = inode->i_security;
2859         u32 newsid;
2860         int rc;
2861
2862         if (strcmp(name, XATTR_SELINUX_SUFFIX))
2863                 return -EOPNOTSUPP;
2864
2865         if (!value || !size)
2866                 return -EACCES;
2867
2868         rc = security_context_to_sid((void *)value, size, &newsid);
2869         if (rc)
2870                 return rc;
2871
2872         isec->sid = newsid;
2873         isec->initialized = 1;
2874         return 0;
2875 }
2876
2877 static int selinux_inode_listsecurity(struct inode *inode, char *buffer, size_t buffer_size)
2878 {
2879         const int len = sizeof(XATTR_NAME_SELINUX);
2880         if (buffer && len <= buffer_size)
2881                 memcpy(buffer, XATTR_NAME_SELINUX, len);
2882         return len;
2883 }
2884
2885 static void selinux_inode_getsecid(const struct inode *inode, u32 *secid)
2886 {
2887         struct inode_security_struct *isec = inode->i_security;
2888         *secid = isec->sid;
2889 }
2890
2891 /* file security operations */
2892
2893 static int selinux_revalidate_file_permission(struct file *file, int mask)
2894 {
2895         const struct cred *cred = current_cred();
2896         struct inode *inode = file->f_path.dentry->d_inode;
2897
2898         /* file_mask_to_av won't add FILE__WRITE if MAY_APPEND is set */
2899         if ((file->f_flags & O_APPEND) && (mask & MAY_WRITE))
2900                 mask |= MAY_APPEND;
2901
2902         return file_has_perm(cred, file,
2903                              file_mask_to_av(inode->i_mode, mask));
2904 }
2905
2906 static int selinux_file_permission(struct file *file, int mask)
2907 {
2908         struct inode *inode = file->f_path.dentry->d_inode;
2909         struct file_security_struct *fsec = file->f_security;
2910         struct inode_security_struct *isec = inode->i_security;
2911         u32 sid = current_sid();
2912
2913         if (!mask)
2914                 /* No permission to check.  Existence test. */
2915                 return 0;
2916
2917         if (sid == fsec->sid && fsec->isid == isec->sid &&
2918             fsec->pseqno == avc_policy_seqno())
2919                 /* No change since dentry_open check. */
2920                 return 0;
2921
2922         return selinux_revalidate_file_permission(file, mask);
2923 }
2924
2925 static int selinux_file_alloc_security(struct file *file)
2926 {
2927         return file_alloc_security(file);
2928 }
2929
2930 static void selinux_file_free_security(struct file *file)
2931 {
2932         file_free_security(file);
2933 }
2934
2935 static int selinux_file_ioctl(struct file *file, unsigned int cmd,
2936                               unsigned long arg)
2937 {
2938         const struct cred *cred = current_cred();
2939         u32 av = 0;
2940
2941         if (_IOC_DIR(cmd) & _IOC_WRITE)
2942                 av |= FILE__WRITE;
2943         if (_IOC_DIR(cmd) & _IOC_READ)
2944                 av |= FILE__READ;
2945         if (!av)
2946                 av = FILE__IOCTL;
2947
2948         return file_has_perm(cred, file, av);
2949 }
2950
2951 static int default_noexec;
2952
2953 static int file_map_prot_check(struct file *file, unsigned long prot, int shared)
2954 {
2955         const struct cred *cred = current_cred();
2956         int rc = 0;
2957
2958         if (default_noexec &&
2959             (prot & PROT_EXEC) && (!file || (!shared && (prot & PROT_WRITE)))) {
2960                 /*
2961                  * We are making executable an anonymous mapping or a
2962                  * private file mapping that will also be writable.
2963                  * This has an additional check.
2964                  */
2965                 rc = cred_has_perm(cred, cred, PROCESS__EXECMEM);
2966                 if (rc)
2967                         goto error;
2968         }
2969
2970         if (file) {
2971                 /* read access is always possible with a mapping */
2972                 u32 av = FILE__READ;
2973
2974                 /* write access only matters if the mapping is shared */
2975                 if (shared && (prot & PROT_WRITE))
2976                         av |= FILE__WRITE;
2977
2978                 if (prot & PROT_EXEC)
2979                         av |= FILE__EXECUTE;
2980
2981                 return file_has_perm(cred, file, av);
2982         }
2983
2984 error:
2985         return rc;
2986 }
2987
2988 static int selinux_file_mmap(struct file *file, unsigned long reqprot,
2989                              unsigned long prot, unsigned long flags,
2990                              unsigned long addr, unsigned long addr_only)
2991 {
2992         int rc = 0;
2993         u32 sid = current_sid();
2994
2995         /*
2996          * notice that we are intentionally putting the SELinux check before
2997          * the secondary cap_file_mmap check.  This is such a likely attempt
2998          * at bad behaviour/exploit that we always want to get the AVC, even
2999          * if DAC would have also denied the operation.
3000          */
3001         if (addr < CONFIG_LSM_MMAP_MIN_ADDR) {
3002                 rc = avc_has_perm(sid, sid, SECCLASS_MEMPROTECT,
3003                                   MEMPROTECT__MMAP_ZERO, NULL);
3004                 if (rc)
3005                         return rc;
3006         }
3007
3008         /* do DAC check on address space usage */
3009         rc = cap_file_mmap(file, reqprot, prot, flags, addr, addr_only);
3010         if (rc || addr_only)
3011                 return rc;
3012
3013         if (selinux_checkreqprot)
3014                 prot = reqprot;
3015
3016         return file_map_prot_check(file, prot,
3017                                    (flags & MAP_TYPE) == MAP_SHARED);
3018 }
3019
3020 static int selinux_file_mprotect(struct vm_area_struct *vma,
3021                                  unsigned long reqprot,
3022                                  unsigned long prot)
3023 {
3024         const struct cred *cred = current_cred();
3025
3026         if (selinux_checkreqprot)
3027                 prot = reqprot;
3028
3029         if (default_noexec &&
3030             (prot & PROT_EXEC) && !(vma->vm_flags & VM_EXEC)) {
3031                 int rc = 0;
3032                 if (vma->vm_start >= vma->vm_mm->start_brk &&
3033                     vma->vm_end <= vma->vm_mm->brk) {
3034                         rc = cred_has_perm(cred, cred, PROCESS__EXECHEAP);
3035                 } else if (!vma->vm_file &&
3036                            vma->vm_start <= vma->vm_mm->start_stack &&
3037                            vma->vm_end >= vma->vm_mm->start_stack) {
3038                         rc = current_has_perm(current, PROCESS__EXECSTACK);
3039                 } else if (vma->vm_file && vma->anon_vma) {
3040                         /*
3041                          * We are making executable a file mapping that has
3042                          * had some COW done. Since pages might have been
3043                          * written, check ability to execute the possibly
3044                          * modified content.  This typically should only
3045                          * occur for text relocations.
3046                          */
3047                         rc = file_has_perm(cred, vma->vm_file, FILE__EXECMOD);
3048                 }
3049                 if (rc)
3050                         return rc;
3051         }
3052
3053         return file_map_prot_check(vma->vm_file, prot, vma->vm_flags&VM_SHARED);
3054 }
3055
3056 static int selinux_file_lock(struct file *file, unsigned int cmd)
3057 {
3058         const struct cred *cred = current_cred();
3059
3060         return file_has_perm(cred, file, FILE__LOCK);
3061 }
3062
3063 static int selinux_file_fcntl(struct file *file, unsigned int cmd,
3064                               unsigned long arg)
3065 {
3066         const struct cred *cred = current_cred();
3067         int err = 0;
3068
3069         switch (cmd) {
3070         case F_SETFL:
3071                 if (!file->f_path.dentry || !file->f_path.dentry->d_inode) {
3072                         err = -EINVAL;
3073                         break;
3074                 }
3075
3076                 if ((file->f_flags & O_APPEND) && !(arg & O_APPEND)) {
3077                         err = file_has_perm(cred, file, FILE__WRITE);
3078                         break;
3079                 }
3080                 /* fall through */
3081         case F_SETOWN:
3082         case F_SETSIG:
3083         case F_GETFL:
3084         case F_GETOWN:
3085         case F_GETSIG:
3086                 /* Just check FD__USE permission */
3087                 err = file_has_perm(cred, file, 0);
3088                 break;
3089         case F_GETLK:
3090         case F_SETLK:
3091         case F_SETLKW:
3092 #if BITS_PER_LONG == 32
3093         case F_GETLK64:
3094         case F_SETLK64:
3095         case F_SETLKW64:
3096 #endif
3097                 if (!file->f_path.dentry || !file->f_path.dentry->d_inode) {
3098                         err = -EINVAL;
3099                         break;
3100                 }
3101                 err = file_has_perm(cred, file, FILE__LOCK);
3102                 break;
3103         }
3104
3105         return err;
3106 }
3107
3108 static int selinux_file_set_fowner(struct file *file)
3109 {
3110         struct file_security_struct *fsec;
3111
3112         fsec = file->f_security;
3113         fsec->fown_sid = current_sid();
3114
3115         return 0;
3116 }
3117
3118 static int selinux_file_send_sigiotask(struct task_struct *tsk,
3119                                        struct fown_struct *fown, int signum)
3120 {
3121         struct file *file;
3122         u32 sid = task_sid(tsk);
3123         u32 perm;
3124         struct file_security_struct *fsec;
3125
3126         /* struct fown_struct is never outside the context of a struct file */
3127         file = container_of(fown, struct file, f_owner);
3128
3129         fsec = file->f_security;
3130
3131         if (!signum)
3132                 perm = signal_to_av(SIGIO); /* as per send_sigio_to_task */
3133         else
3134                 perm = signal_to_av(signum);
3135
3136         return avc_has_perm(fsec->fown_sid, sid,
3137                             SECCLASS_PROCESS, perm, NULL);
3138 }
3139
3140 static int selinux_file_receive(struct file *file)
3141 {
3142         const struct cred *cred = current_cred();
3143
3144         return file_has_perm(cred, file, file_to_av(file));
3145 }
3146
3147 static int selinux_dentry_open(struct file *file, const struct cred *cred)
3148 {
3149         struct file_security_struct *fsec;
3150         struct inode *inode;
3151         struct inode_security_struct *isec;
3152
3153         inode = file->f_path.dentry->d_inode;
3154         fsec = file->f_security;
3155         isec = inode->i_security;
3156         /*
3157          * Save inode label and policy sequence number
3158          * at open-time so that selinux_file_permission
3159          * can determine whether revalidation is necessary.
3160          * Task label is already saved in the file security
3161          * struct as its SID.
3162          */
3163         fsec->isid = isec->sid;
3164         fsec->pseqno = avc_policy_seqno();
3165         /*
3166          * Since the inode label or policy seqno may have changed
3167          * between the selinux_inode_permission check and the saving
3168          * of state above, recheck that access is still permitted.
3169          * Otherwise, access might never be revalidated against the
3170          * new inode label or new policy.
3171          * This check is not redundant - do not remove.
3172          */
3173         return inode_has_perm(cred, inode, open_file_to_av(file), NULL);
3174 }
3175
3176 /* task security operations */
3177
3178 static int selinux_task_create(unsigned long clone_flags)
3179 {
3180         return current_has_perm(current, PROCESS__FORK);
3181 }
3182
3183 /*
3184  * allocate the SELinux part of blank credentials
3185  */
3186 static int selinux_cred_alloc_blank(struct cred *cred, gfp_t gfp)
3187 {
3188         struct task_security_struct *tsec;
3189
3190         tsec = kzalloc(sizeof(struct task_security_struct), gfp);
3191         if (!tsec)
3192                 return -ENOMEM;
3193
3194         cred->security = tsec;
3195         return 0;
3196 }
3197
3198 /*
3199  * detach and free the LSM part of a set of credentials
3200  */
3201 static void selinux_cred_free(struct cred *cred)
3202 {
3203         struct task_security_struct *tsec = cred->security;
3204
3205         BUG_ON((unsigned long) cred->security < PAGE_SIZE);
3206         cred->security = (void *) 0x7UL;
3207         kfree(tsec);
3208 }
3209
3210 /*
3211  * prepare a new set of credentials for modification
3212  */
3213 static int selinux_cred_prepare(struct cred *new, const struct cred *old,
3214                                 gfp_t gfp)
3215 {
3216         const struct task_security_struct *old_tsec;
3217         struct task_security_struct *tsec;
3218
3219         old_tsec = old->security;
3220
3221         tsec = kmemdup(old_tsec, sizeof(struct task_security_struct), gfp);
3222         if (!tsec)
3223                 return -ENOMEM;
3224
3225         new->security = tsec;
3226         return 0;
3227 }
3228
3229 /*
3230  * transfer the SELinux data to a blank set of creds
3231  */
3232 static void selinux_cred_transfer(struct cred *new, const struct cred *old)
3233 {
3234         const struct task_security_struct *old_tsec = old->security;
3235         struct task_security_struct *tsec = new->security;
3236
3237         *tsec = *old_tsec;
3238 }
3239
3240 /*
3241  * set the security data for a kernel service
3242  * - all the creation contexts are set to unlabelled
3243  */
3244 static int selinux_kernel_act_as(struct cred *new, u32 secid)
3245 {
3246         struct task_security_struct *tsec = new->security;
3247         u32 sid = current_sid();
3248         int ret;
3249
3250         ret = avc_has_perm(sid, secid,
3251                            SECCLASS_KERNEL_SERVICE,
3252                            KERNEL_SERVICE__USE_AS_OVERRIDE,
3253                            NULL);
3254         if (ret == 0) {
3255                 tsec->sid = secid;
3256                 tsec->create_sid = 0;
3257                 tsec->keycreate_sid = 0;
3258                 tsec->sockcreate_sid = 0;
3259         }
3260         return ret;
3261 }
3262
3263 /*
3264  * set the file creation context in a security record to the same as the
3265  * objective context of the specified inode
3266  */
3267 static int selinux_kernel_create_files_as(struct cred *new, struct inode *inode)
3268 {
3269         struct inode_security_struct *isec = inode->i_security;
3270         struct task_security_struct *tsec = new->security;
3271         u32 sid = current_sid();
3272         int ret;
3273
3274         ret = avc_has_perm(sid, isec->sid,
3275                            SECCLASS_KERNEL_SERVICE,
3276                            KERNEL_SERVICE__CREATE_FILES_AS,
3277                            NULL);
3278
3279         if (ret == 0)
3280                 tsec->create_sid = isec->sid;
3281         return ret;
3282 }
3283
3284 static int selinux_kernel_module_request(char *kmod_name)
3285 {
3286         u32 sid;
3287         struct common_audit_data ad;
3288
3289         sid = task_sid(current);
3290
3291         COMMON_AUDIT_DATA_INIT(&ad, KMOD);
3292         ad.u.kmod_name = kmod_name;
3293
3294         return avc_has_perm(sid, SECINITSID_KERNEL, SECCLASS_SYSTEM,
3295                             SYSTEM__MODULE_REQUEST, &ad);
3296 }
3297
3298 static int selinux_task_setpgid(struct task_struct *p, pid_t pgid)
3299 {
3300         return current_has_perm(p, PROCESS__SETPGID);
3301 }
3302
3303 static int selinux_task_getpgid(struct task_struct *p)
3304 {
3305         return current_has_perm(p, PROCESS__GETPGID);
3306 }
3307
3308 static int selinux_task_getsid(struct task_struct *p)
3309 {
3310         return current_has_perm(p, PROCESS__GETSESSION);
3311 }
3312
3313 static void selinux_task_getsecid(struct task_struct *p, u32 *secid)
3314 {
3315         *secid = task_sid(p);
3316 }
3317
3318 static int selinux_task_setnice(struct task_struct *p, int nice)
3319 {
3320         int rc;
3321
3322         rc = cap_task_setnice(p, nice);
3323         if (rc)
3324                 return rc;
3325
3326         return current_has_perm(p, PROCESS__SETSCHED);
3327 }
3328
3329 static int selinux_task_setioprio(struct task_struct *p, int ioprio)
3330 {
3331         int rc;
3332
3333         rc = cap_task_setioprio(p, ioprio);
3334         if (rc)
3335                 return rc;
3336
3337         return current_has_perm(p, PROCESS__SETSCHED);
3338 }
3339
3340 static int selinux_task_getioprio(struct task_struct *p)
3341 {
3342         return current_has_perm(p, PROCESS__GETSCHED);
3343 }
3344
3345 static int selinux_task_setrlimit(unsigned int resource, struct rlimit *new_rlim)
3346 {
3347         struct rlimit *old_rlim = current->signal->rlim + resource;
3348
3349         /* Control the ability to change the hard limit (whether
3350            lowering or raising it), so that the hard limit can
3351            later be used as a safe reset point for the soft limit
3352            upon context transitions.  See selinux_bprm_committing_creds. */
3353         if (old_rlim->rlim_max != new_rlim->rlim_max)
3354                 return current_has_perm(current, PROCESS__SETRLIMIT);
3355
3356         return 0;
3357 }
3358
3359 static int selinux_task_setscheduler(struct task_struct *p, int policy, struct sched_param *lp)
3360 {
3361         int rc;
3362
3363         rc = cap_task_setscheduler(p, policy, lp);
3364         if (rc)
3365                 return rc;
3366
3367         return current_has_perm(p, PROCESS__SETSCHED);
3368 }
3369
3370 static int selinux_task_getscheduler(struct task_struct *p)
3371 {
3372         return current_has_perm(p, PROCESS__GETSCHED);
3373 }
3374
3375 static int selinux_task_movememory(struct task_struct *p)
3376 {
3377         return current_has_perm(p, PROCESS__SETSCHED);
3378 }
3379
3380 static int selinux_task_kill(struct task_struct *p, struct siginfo *info,
3381                                 int sig, u32 secid)
3382 {
3383         u32 perm;
3384         int rc;
3385
3386         if (!sig)
3387                 perm = PROCESS__SIGNULL; /* null signal; existence test */
3388         else
3389                 perm = signal_to_av(sig);
3390         if (secid)
3391                 rc = avc_has_perm(secid, task_sid(p),
3392                                   SECCLASS_PROCESS, perm, NULL);
3393         else
3394                 rc = current_has_perm(p, perm);
3395         return rc;
3396 }
3397
3398 static int selinux_task_wait(struct task_struct *p)
3399 {
3400         return task_has_perm(p, current, PROCESS__SIGCHLD);
3401 }
3402
3403 static void selinux_task_to_inode(struct task_struct *p,
3404                                   struct inode *inode)
3405 {
3406         struct inode_security_struct *isec = inode->i_security;
3407         u32 sid = task_sid(p);
3408
3409         isec->sid = sid;
3410         isec->initialized = 1;
3411 }
3412
3413 /* Returns error only if unable to parse addresses */
3414 static int selinux_parse_skb_ipv4(struct sk_buff *skb,
3415                         struct common_audit_data *ad, u8 *proto)
3416 {
3417         int offset, ihlen, ret = -EINVAL;
3418         struct iphdr _iph, *ih;
3419
3420         offset = skb_network_offset(skb);
3421         ih = skb_header_pointer(skb, offset, sizeof(_iph), &_iph);
3422         if (ih == NULL)
3423                 goto out;
3424
3425         ihlen = ih->ihl * 4;
3426         if (ihlen < sizeof(_iph))
3427                 goto out;
3428
3429         ad->u.net.v4info.saddr = ih->saddr;
3430         ad->u.net.v4info.daddr = ih->daddr;
3431         ret = 0;
3432
3433         if (proto)
3434                 *proto = ih->protocol;
3435
3436         switch (ih->protocol) {
3437         case IPPROTO_TCP: {
3438                 struct tcphdr _tcph, *th;
3439
3440                 if (ntohs(ih->frag_off) & IP_OFFSET)
3441                         break;
3442
3443                 offset += ihlen;
3444                 th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph);
3445                 if (th == NULL)
3446                         break;
3447
3448                 ad->u.net.sport = th->source;
3449                 ad->u.net.dport = th->dest;
3450                 break;
3451         }
3452
3453         case IPPROTO_UDP: {
3454                 struct udphdr _udph, *uh;
3455
3456                 if (ntohs(ih->frag_off) & IP_OFFSET)
3457                         break;
3458
3459                 offset += ihlen;
3460                 uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph);
3461                 if (uh == NULL)
3462                         break;
3463
3464                 ad->u.net.sport = uh->source;
3465                 ad->u.net.dport = uh->dest;
3466                 break;
3467         }
3468
3469         case IPPROTO_DCCP: {
3470                 struct dccp_hdr _dccph, *dh;
3471
3472                 if (ntohs(ih->frag_off) & IP_OFFSET)
3473                         break;
3474
3475                 offset += ihlen;
3476                 dh = skb_header_pointer(skb, offset, sizeof(_dccph), &_dccph);
3477                 if (dh == NULL)
3478                         break;
3479
3480                 ad->u.net.sport = dh->dccph_sport;
3481                 ad->u.net.dport = dh->dccph_dport;
3482                 break;
3483         }
3484
3485         default:
3486                 break;
3487         }
3488 out:
3489         return ret;
3490 }
3491
3492 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
3493
3494 /* Returns error only if unable to parse addresses */
3495 static int selinux_parse_skb_ipv6(struct sk_buff *skb,
3496                         struct common_audit_data *ad, u8 *proto)
3497 {
3498         u8 nexthdr;
3499         int ret = -EINVAL, offset;
3500         struct ipv6hdr _ipv6h, *ip6;
3501
3502         offset = skb_network_offset(skb);
3503         ip6 = skb_header_pointer(skb, offset, sizeof(_ipv6h), &_ipv6h);
3504         if (ip6 == NULL)
3505                 goto out;
3506
3507         ipv6_addr_copy(&ad->u.net.v6info.saddr, &ip6->saddr);
3508         ipv6_addr_copy(&ad->u.net.v6info.daddr, &ip6->daddr);
3509         ret = 0;
3510
3511         nexthdr = ip6->nexthdr;
3512         offset += sizeof(_ipv6h);
3513         offset = ipv6_skip_exthdr(skb, offset, &nexthdr);
3514         if (offset < 0)
3515                 goto out;
3516
3517         if (proto)
3518                 *proto = nexthdr;
3519
3520         switch (nexthdr) {
3521         case IPPROTO_TCP: {
3522                 struct tcphdr _tcph, *th;
3523
3524                 th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph);
3525                 if (th == NULL)
3526                         break;
3527
3528                 ad->u.net.sport = th->source;
3529                 ad->u.net.dport = th->dest;
3530                 break;
3531         }
3532
3533         case IPPROTO_UDP: {
3534                 struct udphdr _udph, *uh;
3535
3536                 uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph);
3537                 if (uh == NULL)
3538                         break;
3539
3540                 ad->u.net.sport = uh->source;
3541                 ad->u.net.dport = uh->dest;
3542                 break;
3543         }
3544
3545         case IPPROTO_DCCP: {
3546                 struct dccp_hdr _dccph, *dh;
3547
3548                 dh = skb_header_pointer(skb, offset, sizeof(_dccph), &_dccph);
3549                 if (dh == NULL)
3550                         break;
3551
3552                 ad->u.net.sport = dh->dccph_sport;
3553                 ad->u.net.dport = dh->dccph_dport;
3554                 break;
3555         }
3556
3557         /* includes fragments */
3558         default:
3559                 break;
3560         }
3561 out:
3562         return ret;
3563 }
3564
3565 #endif /* IPV6 */
3566
3567 static int selinux_parse_skb(struct sk_buff *skb, struct common_audit_data *ad,
3568                              char **_addrp, int src, u8 *proto)
3569 {
3570         char *addrp;
3571         int ret;
3572
3573         switch (ad->u.net.family) {
3574         case PF_INET:
3575                 ret = selinux_parse_skb_ipv4(skb, ad, proto);
3576                 if (ret)
3577                         goto parse_error;
3578                 addrp = (char *)(src ? &ad->u.net.v4info.saddr :
3579                                        &ad->u.net.v4info.daddr);
3580                 goto okay;
3581
3582 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
3583         case PF_INET6:
3584                 ret = selinux_parse_skb_ipv6(skb, ad, proto);
3585                 if (ret)
3586                         goto parse_error;
3587                 addrp = (char *)(src ? &ad->u.net.v6info.saddr :
3588                                        &ad->u.net.v6info.daddr);
3589                 goto okay;
3590 #endif  /* IPV6 */
3591         default:
3592                 addrp = NULL;
3593                 goto okay;
3594         }
3595
3596 parse_error:
3597         printk(KERN_WARNING
3598                "SELinux: failure in selinux_parse_skb(),"
3599                " unable to parse packet\n");
3600         return ret;
3601
3602 okay:
3603         if (_addrp)
3604                 *_addrp = addrp;
3605         return 0;
3606 }
3607
3608 /**
3609  * selinux_skb_peerlbl_sid - Determine the peer label of a packet
3610  * @skb: the packet
3611  * @family: protocol family
3612  * @sid: the packet's peer label SID
3613  *
3614  * Description:
3615  * Check the various different forms of network peer labeling and determine
3616  * the peer label/SID for the packet; most of the magic actually occurs in
3617  * the security server function security_net_peersid_cmp().  The function
3618  * returns zero if the value in @sid is valid (although it may be SECSID_NULL)
3619  * or -EACCES if @sid is invalid due to inconsistencies with the different
3620  * peer labels.
3621  *
3622  */
3623 static int selinux_skb_peerlbl_sid(struct sk_buff *skb, u16 family, u32 *sid)
3624 {
3625         int err;
3626         u32 xfrm_sid;
3627         u32 nlbl_sid;
3628         u32 nlbl_type;
3629
3630         selinux_skb_xfrm_sid(skb, &xfrm_sid);
3631         selinux_netlbl_skbuff_getsid(skb, family, &nlbl_type, &nlbl_sid);
3632
3633         err = security_net_peersid_resolve(nlbl_sid, nlbl_type, xfrm_sid, sid);
3634         if (unlikely(err)) {
3635                 printk(KERN_WARNING
3636                        "SELinux: failure in selinux_skb_peerlbl_sid(),"
3637                        " unable to determine packet's peer label\n");
3638                 return -EACCES;
3639         }
3640
3641         return 0;
3642 }
3643
3644 /* socket security operations */
3645
3646 static u32 socket_sockcreate_sid(const struct task_security_struct *tsec)
3647 {
3648         return tsec->sockcreate_sid ? : tsec->sid;
3649 }
3650
3651 static int sock_has_perm(struct task_struct *task, struct sock *sk, u32 perms)
3652 {
3653         struct sk_security_struct *sksec = sk->sk_security;
3654         struct common_audit_data ad;
3655         u32 tsid = task_sid(task);
3656
3657         if (sksec->sid == SECINITSID_KERNEL)
3658                 return 0;
3659
3660         COMMON_AUDIT_DATA_INIT(&ad, NET);
3661         ad.u.net.sk = sk;
3662
3663         return avc_has_perm(tsid, sksec->sid, sksec->sclass, perms, &ad);
3664 }
3665
3666 static int selinux_socket_create(int family, int type,
3667                                  int protocol, int kern)
3668 {
3669         const struct task_security_struct *tsec = current_security();
3670         u32 newsid;
3671         u16 secclass;
3672
3673         if (kern)
3674                 return 0;
3675
3676         newsid = socket_sockcreate_sid(tsec);
3677         secclass = socket_type_to_security_class(family, type, protocol);
3678         return avc_has_perm(tsec->sid, newsid, secclass, SOCKET__CREATE, NULL);
3679 }
3680
3681 static int selinux_socket_post_create(struct socket *sock, int family,
3682                                       int type, int protocol, int kern)
3683 {
3684         const struct task_security_struct *tsec = current_security();
3685         struct inode_security_struct *isec = SOCK_INODE(sock)->i_security;
3686         struct sk_security_struct *sksec;
3687         int err = 0;
3688
3689         if (kern)
3690                 isec->sid = SECINITSID_KERNEL;
3691         else
3692                 isec->sid = socket_sockcreate_sid(tsec);
3693
3694         isec->sclass = socket_type_to_security_class(family, type, protocol);
3695         isec->initialized = 1;
3696
3697         if (sock->sk) {
3698                 sksec = sock->sk->sk_security;
3699                 sksec->sid = isec->sid;
3700                 sksec->sclass = isec->sclass;
3701                 err = selinux_netlbl_socket_post_create(sock->sk, family);
3702         }
3703
3704         return err;
3705 }
3706
3707 /* Range of port numbers used to automatically bind.
3708    Need to determine whether we should perform a name_bind
3709    permission check between the socket and the port number. */
3710
3711 static int selinux_socket_bind(struct socket *sock, struct sockaddr *address, int addrlen)
3712 {
3713         struct sock *sk = sock->sk;
3714         u16 family;
3715         int err;
3716
3717         err = sock_has_perm(current, sk, SOCKET__BIND);
3718         if (err)
3719                 goto out;
3720
3721         /*
3722          * If PF_INET or PF_INET6, check name_bind permission for the port.
3723          * Multiple address binding for SCTP is not supported yet: we just
3724          * check the first address now.
3725          */
3726         family = sk->sk_family;
3727         if (family == PF_INET || family == PF_INET6) {
3728                 char *addrp;
3729                 struct sk_security_struct *sksec = sk->sk_security;
3730                 struct common_audit_data ad;
3731                 struct sockaddr_in *addr4 = NULL;
3732                 struct sockaddr_in6 *addr6 = NULL;
3733                 unsigned short snum;
3734                 u32 sid, node_perm;
3735
3736                 if (family == PF_INET) {
3737                         addr4 = (struct sockaddr_in *)address;
3738                         snum = ntohs(addr4->sin_port);
3739                         addrp = (char *)&addr4->sin_addr.s_addr;
3740                 } else {
3741                         addr6 = (struct sockaddr_in6 *)address;
3742                         snum = ntohs(addr6->sin6_port);
3743                         addrp = (char *)&addr6->sin6_addr.s6_addr;
3744                 }
3745
3746                 if (snum) {
3747                         int low, high;
3748
3749                         inet_get_local_port_range(&low, &high);
3750
3751                         if (snum < max(PROT_SOCK, low) || snum > high) {
3752                                 err = sel_netport_sid(sk->sk_protocol,
3753                                                       snum, &sid);
3754                                 if (err)
3755                                         goto out;
3756                                 COMMON_AUDIT_DATA_INIT(&ad, NET);
3757                                 ad.u.net.sport = htons(snum);
3758                                 ad.u.net.family = family;
3759                                 err = avc_has_perm(sksec->sid, sid,
3760                                                    sksec->sclass,
3761                                                    SOCKET__NAME_BIND, &ad);
3762                                 if (err)
3763                                         goto out;
3764                         }
3765                 }
3766
3767                 switch (sksec->sclass) {
3768                 case SECCLASS_TCP_SOCKET:
3769                         node_perm = TCP_SOCKET__NODE_BIND;
3770                         break;
3771
3772                 case SECCLASS_UDP_SOCKET:
3773                         node_perm = UDP_SOCKET__NODE_BIND;
3774                         break;
3775
3776                 case SECCLASS_DCCP_SOCKET:
3777                         node_perm = DCCP_SOCKET__NODE_BIND;
3778                         break;
3779
3780                 default:
3781                         node_perm = RAWIP_SOCKET__NODE_BIND;
3782                         break;
3783                 }
3784
3785                 err = sel_netnode_sid(addrp, family, &sid);
3786                 if (err)
3787                         goto out;
3788
3789                 COMMON_AUDIT_DATA_INIT(&ad, NET);
3790                 ad.u.net.sport = htons(snum);
3791                 ad.u.net.family = family;
3792
3793                 if (family == PF_INET)
3794                         ad.u.net.v4info.saddr = addr4->sin_addr.s_addr;
3795                 else
3796                         ipv6_addr_copy(&ad.u.net.v6info.saddr, &addr6->sin6_addr);
3797
3798                 err = avc_has_perm(sksec->sid, sid,
3799                                    sksec->sclass, node_perm, &ad);
3800                 if (err)
3801                         goto out;
3802         }
3803 out:
3804         return err;
3805 }
3806
3807 static int selinux_socket_connect(struct socket *sock, struct sockaddr *address, int addrlen)
3808 {
3809         struct sock *sk = sock->sk;
3810         struct sk_security_struct *sksec = sk->sk_security;
3811         int err;
3812
3813         err = sock_has_perm(current, sk, SOCKET__CONNECT);
3814         if (err)
3815                 return err;
3816
3817         /*
3818          * If a TCP or DCCP socket, check name_connect permission for the port.
3819          */
3820         if (sksec->sclass == SECCLASS_TCP_SOCKET ||
3821             sksec->sclass == SECCLASS_DCCP_SOCKET) {
3822                 struct common_audit_data ad;
3823                 struct sockaddr_in *addr4 = NULL;
3824                 struct sockaddr_in6 *addr6 = NULL;
3825                 unsigned short snum;
3826                 u32 sid, perm;
3827
3828                 if (sk->sk_family == PF_INET) {
3829                         addr4 = (struct sockaddr_in *)address;
3830                         if (addrlen < sizeof(struct sockaddr_in))
3831                                 return -EINVAL;
3832                         snum = ntohs(addr4->sin_port);
3833                 } else {
3834                         addr6 = (struct sockaddr_in6 *)address;
3835                         if (addrlen < SIN6_LEN_RFC2133)
3836                                 return -EINVAL;
3837                         snum = ntohs(addr6->sin6_port);
3838                 }
3839
3840                 err = sel_netport_sid(sk->sk_protocol, snum, &sid);
3841                 if (err)
3842                         goto out;
3843
3844                 perm = (sksec->sclass == SECCLASS_TCP_SOCKET) ?
3845                        TCP_SOCKET__NAME_CONNECT : DCCP_SOCKET__NAME_CONNECT;
3846
3847                 COMMON_AUDIT_DATA_INIT(&ad, NET);
3848                 ad.u.net.dport = htons(snum);
3849                 ad.u.net.family = sk->sk_family;
3850                 err = avc_has_perm(sksec->sid, sid, sksec->sclass, perm, &ad);
3851                 if (err)
3852                         goto out;
3853         }
3854
3855         err = selinux_netlbl_socket_connect(sk, address);
3856
3857 out:
3858         return err;
3859 }
3860
3861 static int selinux_socket_listen(struct socket *sock, int backlog)
3862 {
3863         return sock_has_perm(current, sock->sk, SOCKET__LISTEN);
3864 }
3865
3866 static int selinux_socket_accept(struct socket *sock, struct socket *newsock)
3867 {
3868         int err;
3869         struct inode_security_struct *isec;
3870         struct inode_security_struct *newisec;
3871
3872         err = sock_has_perm(current, sock->sk, SOCKET__ACCEPT);
3873         if (err)
3874                 return err;
3875
3876         newisec = SOCK_INODE(newsock)->i_security;
3877
3878         isec = SOCK_INODE(sock)->i_security;
3879         newisec->sclass = isec->sclass;
3880         newisec->sid = isec->sid;
3881         newisec->initialized = 1;
3882
3883         return 0;
3884 }
3885
3886 static int selinux_socket_sendmsg(struct socket *sock, struct msghdr *msg,
3887                                   int size)
3888 {
3889         return sock_has_perm(current, sock->sk, SOCKET__WRITE);
3890 }
3891
3892 static int selinux_socket_recvmsg(struct socket *sock, struct msghdr *msg,
3893                                   int size, int flags)
3894 {
3895         return sock_has_perm(current, sock->sk, SOCKET__READ);
3896 }
3897
3898 static int selinux_socket_getsockname(struct socket *sock)
3899 {
3900         return sock_has_perm(current, sock->sk, SOCKET__GETATTR);
3901 }
3902
3903 static int selinux_socket_getpeername(struct socket *sock)
3904 {
3905         return sock_has_perm(current, sock->sk, SOCKET__GETATTR);
3906 }
3907
3908 static int selinux_socket_setsockopt(struct socket *sock, int level, int optname)
3909 {
3910         int err;
3911
3912         err = sock_has_perm(current, sock->sk, SOCKET__SETOPT);
3913         if (err)
3914                 return err;
3915
3916         return selinux_netlbl_socket_setsockopt(sock, level, optname);
3917 }
3918
3919 static int selinux_socket_getsockopt(struct socket *sock, int level,
3920                                      int optname)
3921 {
3922         return sock_has_perm(current, sock->sk, SOCKET__GETOPT);
3923 }
3924
3925 static int selinux_socket_shutdown(struct socket *sock, int how)
3926 {
3927         return sock_has_perm(current, sock->sk, SOCKET__SHUTDOWN);
3928 }
3929
3930 static int selinux_socket_unix_stream_connect(struct socket *sock,
3931                                               struct socket *other,
3932                                               struct sock *newsk)
3933 {
3934         struct sk_security_struct *sksec_sock = sock->sk->sk_security;
3935         struct sk_security_struct *sksec_other = other->sk->sk_security;
3936         struct sk_security_struct *sksec_new = newsk->sk_security;
3937         struct common_audit_data ad;
3938         int err;
3939
3940         COMMON_AUDIT_DATA_INIT(&ad, NET);
3941         ad.u.net.sk = other->sk;
3942
3943         err = avc_has_perm(sksec_sock->sid, sksec_other->sid,
3944                            sksec_other->sclass,
3945                            UNIX_STREAM_SOCKET__CONNECTTO, &ad);
3946         if (err)
3947                 return err;
3948
3949         /* server child socket */
3950         sksec_new->peer_sid = sksec_sock->sid;
3951         err = security_sid_mls_copy(sksec_other->sid, sksec_sock->sid,
3952                                     &sksec_new->sid);
3953         if (err)
3954                 return err;
3955
3956         /* connecting socket */
3957         sksec_sock->peer_sid = sksec_new->sid;
3958
3959         return 0;
3960 }
3961
3962 static int selinux_socket_unix_may_send(struct socket *sock,
3963                                         struct socket *other)
3964 {
3965         struct sk_security_struct *ssec = sock->sk->sk_security;
3966         struct sk_security_struct *osec = other->sk->sk_security;
3967         struct common_audit_data ad;
3968
3969         COMMON_AUDIT_DATA_INIT(&ad, NET);
3970         ad.u.net.sk = other->sk;
3971
3972         return avc_has_perm(ssec->sid, osec->sid, osec->sclass, SOCKET__SENDTO,
3973                             &ad);
3974 }
3975
3976 static int selinux_inet_sys_rcv_skb(int ifindex, char *addrp, u16 family,
3977                                     u32 peer_sid,
3978                                     struct common_audit_data *ad)
3979 {
3980         int err;
3981         u32 if_sid;
3982         u32 node_sid;
3983
3984         err = sel_netif_sid(ifindex, &if_sid);
3985         if (err)
3986                 return err;
3987         err = avc_has_perm(peer_sid, if_sid,
3988                            SECCLASS_NETIF, NETIF__INGRESS, ad);
3989         if (err)
3990                 return err;
3991
3992         err = sel_netnode_sid(addrp, family, &node_sid);
3993         if (err)
3994                 return err;
3995         return avc_has_perm(peer_sid, node_sid,
3996                             SECCLASS_NODE, NODE__RECVFROM, ad);
3997 }
3998
3999 static int selinux_sock_rcv_skb_compat(struct sock *sk, struct sk_buff *skb,
4000                                        u16 family)
4001 {
4002         int err = 0;
4003         struct sk_security_struct *sksec = sk->sk_security;
4004         u32 peer_sid;
4005         u32 sk_sid = sksec->sid;
4006         struct common_audit_data ad;
4007         char *addrp;
4008
4009         COMMON_AUDIT_DATA_INIT(&ad, NET);
4010         ad.u.net.netif = skb->skb_iif;
4011         ad.u.net.family = family;
4012         err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL);
4013         if (err)
4014                 return err;
4015
4016         if (selinux_secmark_enabled()) {
4017                 err = avc_has_perm(sk_sid, skb->secmark, SECCLASS_PACKET,
4018                                    PACKET__RECV, &ad);
4019                 if (err)
4020                         return err;
4021         }
4022
4023         if (selinux_policycap_netpeer) {
4024                 err = selinux_skb_peerlbl_sid(skb, family, &peer_sid);
4025                 if (err)
4026                         return err;
4027                 err = avc_has_perm(sk_sid, peer_sid,
4028                                    SECCLASS_PEER, PEER__RECV, &ad);
4029                 if (err)
4030                         selinux_netlbl_err(skb, err, 0);
4031         } else {
4032                 err = selinux_netlbl_sock_rcv_skb(sksec, skb, family, &ad);
4033                 if (err)
4034                         return err;
4035                 err = selinux_xfrm_sock_rcv_skb(sksec->sid, skb, &ad);
4036         }
4037
4038         return err;
4039 }
4040
4041 static int selinux_socket_sock_rcv_skb(struct sock *sk, struct sk_buff *skb)
4042 {
4043         int err;
4044         struct sk_security_struct *sksec = sk->sk_security;
4045         u16 family = sk->sk_family;
4046         u32 sk_sid = sksec->sid;
4047         struct common_audit_data ad;
4048         char *addrp;
4049         u8 secmark_active;
4050         u8 peerlbl_active;
4051
4052         if (family != PF_INET && family != PF_INET6)
4053                 return 0;
4054
4055         /* Handle mapped IPv4 packets arriving via IPv6 sockets */
4056         if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
4057                 family = PF_INET;
4058
4059         /* If any sort of compatibility mode is enabled then handoff processing
4060          * to the selinux_sock_rcv_skb_compat() function to deal with the
4061          * special handling.  We do this in an attempt to keep this function
4062          * as fast and as clean as possible. */
4063         if (!selinux_policycap_netpeer)
4064                 return selinux_sock_rcv_skb_compat(sk, skb, family);
4065
4066         secmark_active = selinux_secmark_enabled();
4067         peerlbl_active = netlbl_enabled() || selinux_xfrm_enabled();
4068         if (!secmark_active && !peerlbl_active)
4069                 return 0;
4070
4071         COMMON_AUDIT_DATA_INIT(&ad, NET);
4072         ad.u.net.netif = skb->skb_iif;
4073         ad.u.net.family = family;
4074         err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL);
4075         if (err)
4076                 return err;
4077
4078         if (peerlbl_active) {
4079                 u32 peer_sid;
4080
4081                 err = selinux_skb_peerlbl_sid(skb, family, &peer_sid);
4082                 if (err)
4083                         return err;
4084                 err = selinux_inet_sys_rcv_skb(skb->skb_iif, addrp, family,
4085                                                peer_sid, &ad);
4086                 if (err) {
4087                         selinux_netlbl_err(skb, err, 0);
4088                         return err;
4089                 }
4090                 err = avc_has_perm(sk_sid, peer_sid, SECCLASS_PEER,
4091                                    PEER__RECV, &ad);
4092                 if (err)
4093                         selinux_netlbl_err(skb, err, 0);
4094         }
4095
4096         if (secmark_active) {
4097                 err = avc_has_perm(sk_sid, skb->secmark, SECCLASS_PACKET,
4098                                    PACKET__RECV, &ad);
4099                 if (err)
4100                         return err;
4101         }
4102
4103         return err;
4104 }
4105
4106 static int selinux_socket_getpeersec_stream(struct socket *sock, char __user *optval,
4107                                             int __user *optlen, unsigned len)
4108 {
4109         int err = 0;
4110         char *scontext;
4111         u32 scontext_len;
4112         struct sk_security_struct *sksec = sock->sk->sk_security;
4113         u32 peer_sid = SECSID_NULL;
4114
4115         if (sksec->sclass == SECCLASS_UNIX_STREAM_SOCKET ||
4116             sksec->sclass == SECCLASS_TCP_SOCKET)
4117                 peer_sid = sksec->peer_sid;
4118         if (peer_sid == SECSID_NULL)
4119                 return -ENOPROTOOPT;
4120
4121         err = security_sid_to_context(peer_sid, &scontext, &scontext_len);
4122         if (err)
4123                 return err;
4124
4125         if (scontext_len > len) {
4126                 err = -ERANGE;
4127                 goto out_len;
4128         }
4129
4130         if (copy_to_user(optval, scontext, scontext_len))
4131                 err = -EFAULT;
4132
4133 out_len:
4134         if (put_user(scontext_len, optlen))
4135                 err = -EFAULT;
4136         kfree(scontext);
4137         return err;
4138 }
4139
4140 static int selinux_socket_getpeersec_dgram(struct socket *sock, struct sk_buff *skb, u32 *secid)
4141 {
4142         u32 peer_secid = SECSID_NULL;
4143         u16 family;
4144
4145         if (skb && skb->protocol == htons(ETH_P_IP))
4146                 family = PF_INET;
4147         else if (skb && skb->protocol == htons(ETH_P_IPV6))
4148                 family = PF_INET6;
4149         else if (sock)
4150                 family = sock->sk->sk_family;
4151         else
4152                 goto out;
4153
4154         if (sock && family == PF_UNIX)
4155                 selinux_inode_getsecid(SOCK_INODE(sock), &peer_secid);
4156         else if (skb)
4157                 selinux_skb_peerlbl_sid(skb, family, &peer_secid);
4158
4159 out:
4160         *secid = peer_secid;
4161         if (peer_secid == SECSID_NULL)
4162                 return -EINVAL;
4163         return 0;
4164 }
4165
4166 static int selinux_sk_alloc_security(struct sock *sk, int family, gfp_t priority)
4167 {
4168         struct sk_security_struct *sksec;
4169
4170         sksec = kzalloc(sizeof(*sksec), priority);
4171         if (!sksec)
4172                 return -ENOMEM;
4173
4174         sksec->peer_sid = SECINITSID_UNLABELED;
4175         sksec->sid = SECINITSID_UNLABELED;
4176         selinux_netlbl_sk_security_reset(sksec);
4177         sk->sk_security = sksec;
4178
4179         return 0;
4180 }
4181
4182 static void selinux_sk_free_security(struct sock *sk)
4183 {
4184         struct sk_security_struct *sksec = sk->sk_security;
4185
4186         sk->sk_security = NULL;
4187         selinux_netlbl_sk_security_free(sksec);
4188         kfree(sksec);
4189 }
4190
4191 static void selinux_sk_clone_security(const struct sock *sk, struct sock *newsk)
4192 {
4193         struct sk_security_struct *sksec = sk->sk_security;
4194         struct sk_security_struct *newsksec = newsk->sk_security;
4195
4196         newsksec->sid = sksec->sid;
4197         newsksec->peer_sid = sksec->peer_sid;
4198         newsksec->sclass = sksec->sclass;
4199
4200         selinux_netlbl_sk_security_reset(newsksec);
4201 }
4202
4203 static void selinux_sk_getsecid(struct sock *sk, u32 *secid)
4204 {
4205         if (!sk)
4206                 *secid = SECINITSID_ANY_SOCKET;
4207         else {
4208                 struct sk_security_struct *sksec = sk->sk_security;
4209
4210                 *secid = sksec->sid;
4211         }
4212 }
4213
4214 static void selinux_sock_graft(struct sock *sk, struct socket *parent)
4215 {
4216         struct inode_security_struct *isec = SOCK_INODE(parent)->i_security;
4217         struct sk_security_struct *sksec = sk->sk_security;
4218
4219         if (sk->sk_family == PF_INET || sk->sk_family == PF_INET6 ||
4220             sk->sk_family == PF_UNIX)
4221                 isec->sid = sksec->sid;
4222         sksec->sclass = isec->sclass;
4223 }
4224
4225 static int selinux_inet_conn_request(struct sock *sk, struct sk_buff *skb,
4226                                      struct request_sock *req)
4227 {
4228         struct sk_security_struct *sksec = sk->sk_security;
4229         int err;
4230         u16 family = sk->sk_family;
4231         u32 newsid;
4232         u32 peersid;
4233
4234         /* handle mapped IPv4 packets arriving via IPv6 sockets */
4235         if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
4236                 family = PF_INET;
4237
4238         err = selinux_skb_peerlbl_sid(skb, family, &peersid);
4239         if (err)
4240                 return err;
4241         if (peersid == SECSID_NULL) {
4242                 req->secid = sksec->sid;
4243                 req->peer_secid = SECSID_NULL;
4244         } else {
4245                 err = security_sid_mls_copy(sksec->sid, peersid, &newsid);
4246                 if (err)
4247                         return err;
4248                 req->secid = newsid;
4249                 req->peer_secid = peersid;
4250         }
4251
4252         return selinux_netlbl_inet_conn_request(req, family);
4253 }
4254
4255 static void selinux_inet_csk_clone(struct sock *newsk,
4256                                    const struct request_sock *req)
4257 {
4258         struct sk_security_struct *newsksec = newsk->sk_security;
4259
4260         newsksec->sid = req->secid;
4261         newsksec->peer_sid = req->peer_secid;
4262         /* NOTE: Ideally, we should also get the isec->sid for the
4263            new socket in sync, but we don't have the isec available yet.
4264            So we will wait until sock_graft to do it, by which
4265            time it will have been created and available. */
4266
4267         /* We don't need to take any sort of lock here as we are the only
4268          * thread with access to newsksec */
4269         selinux_netlbl_inet_csk_clone(newsk, req->rsk_ops->family);
4270 }
4271
4272 static void selinux_inet_conn_established(struct sock *sk, struct sk_buff *skb)
4273 {
4274         u16 family = sk->sk_family;
4275         struct sk_security_struct *sksec = sk->sk_security;
4276
4277         /* handle mapped IPv4 packets arriving via IPv6 sockets */
4278         if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
4279                 family = PF_INET;
4280
4281         selinux_skb_peerlbl_sid(skb, family, &sksec->peer_sid);
4282 }
4283
4284 static void selinux_req_classify_flow(const struct request_sock *req,
4285                                       struct flowi *fl)
4286 {
4287         fl->secid = req->secid;
4288 }
4289
4290 static int selinux_tun_dev_create(void)
4291 {
4292         u32 sid = current_sid();
4293
4294         /* we aren't taking into account the "sockcreate" SID since the socket
4295          * that is being created here is not a socket in the traditional sense,
4296          * instead it is a private sock, accessible only to the kernel, and
4297          * representing a wide range of network traffic spanning multiple
4298          * connections unlike traditional sockets - check the TUN driver to
4299          * get a better understanding of why this socket is special */
4300
4301         return avc_has_perm(sid, sid, SECCLASS_TUN_SOCKET, TUN_SOCKET__CREATE,
4302                             NULL);
4303 }
4304
4305 static void selinux_tun_dev_post_create(struct sock *sk)
4306 {
4307         struct sk_security_struct *sksec = sk->sk_security;
4308
4309         /* we don't currently perform any NetLabel based labeling here and it
4310          * isn't clear that we would want to do so anyway; while we could apply
4311          * labeling without the support of the TUN user the resulting labeled
4312          * traffic from the other end of the connection would almost certainly
4313          * cause confusion to the TUN user that had no idea network labeling
4314          * protocols were being used */
4315
4316         /* see the comments in selinux_tun_dev_create() about why we don't use
4317          * the sockcreate SID here */
4318
4319         sksec->sid = current_sid();
4320         sksec->sclass = SECCLASS_TUN_SOCKET;
4321 }
4322
4323 static int selinux_tun_dev_attach(struct sock *sk)
4324 {
4325         struct sk_security_struct *sksec = sk->sk_security;
4326         u32 sid = current_sid();
4327         int err;
4328
4329         err = avc_has_perm(sid, sksec->sid, SECCLASS_TUN_SOCKET,
4330                            TUN_SOCKET__RELABELFROM, NULL);
4331         if (err)
4332                 return err;
4333         err = avc_has_perm(sid, sid, SECCLASS_TUN_SOCKET,
4334                            TUN_SOCKET__RELABELTO, NULL);
4335         if (err)
4336                 return err;
4337
4338         sksec->sid = sid;
4339
4340         return 0;
4341 }
4342
4343 static int selinux_nlmsg_perm(struct sock *sk, struct sk_buff *skb)
4344 {
4345         int err = 0;
4346         u32 perm;
4347         struct nlmsghdr *nlh;
4348         struct sk_security_struct *sksec = sk->sk_security;
4349
4350         if (skb->len < NLMSG_SPACE(0)) {
4351                 err = -EINVAL;
4352                 goto out;
4353         }
4354         nlh = nlmsg_hdr(skb);
4355
4356         err = selinux_nlmsg_lookup(sksec->sclass, nlh->nlmsg_type, &perm);
4357         if (err) {
4358                 if (err == -EINVAL) {
4359                         audit_log(current->audit_context, GFP_KERNEL, AUDIT_SELINUX_ERR,
4360                                   "SELinux:  unrecognized netlink message"
4361                                   " type=%hu for sclass=%hu\n",
4362                                   nlh->nlmsg_type, sksec->sclass);
4363                         if (!selinux_enforcing || security_get_allow_unknown())
4364                                 err = 0;
4365                 }
4366
4367                 /* Ignore */
4368                 if (err == -ENOENT)
4369                         err = 0;
4370                 goto out;
4371         }
4372
4373         err = sock_has_perm(current, sk, perm);
4374 out:
4375         return err;
4376 }
4377
4378 #ifdef CONFIG_NETFILTER
4379
4380 static unsigned int selinux_ip_forward(struct sk_buff *skb, int ifindex,
4381                                        u16 family)
4382 {
4383         int err;
4384         char *addrp;
4385         u32 peer_sid;
4386         struct common_audit_data ad;
4387         u8 secmark_active;
4388         u8 netlbl_active;
4389         u8 peerlbl_active;
4390
4391         if (!selinux_policycap_netpeer)
4392                 return NF_ACCEPT;
4393
4394         secmark_active = selinux_secmark_enabled();
4395         netlbl_active = netlbl_enabled();
4396         peerlbl_active = netlbl_active || selinux_xfrm_enabled();
4397         if (!secmark_active && !peerlbl_active)
4398                 return NF_ACCEPT;
4399
4400         if (selinux_skb_peerlbl_sid(skb, family, &peer_sid) != 0)
4401                 return NF_DROP;
4402
4403         COMMON_AUDIT_DATA_INIT(&ad, NET);
4404         ad.u.net.netif = ifindex;
4405         ad.u.net.family = family;
4406         if (selinux_parse_skb(skb, &ad, &addrp, 1, NULL) != 0)
4407                 return NF_DROP;
4408
4409         if (peerlbl_active) {
4410                 err = selinux_inet_sys_rcv_skb(ifindex, addrp, family,
4411                                                peer_sid, &ad);
4412                 if (err) {
4413                         selinux_netlbl_err(skb, err, 1);
4414                         return NF_DROP;
4415                 }
4416         }
4417
4418         if (secmark_active)
4419                 if (avc_has_perm(peer_sid, skb->secmark,
4420                                  SECCLASS_PACKET, PACKET__FORWARD_IN, &ad))
4421                         return NF_DROP;
4422
4423         if (netlbl_active)
4424                 /* we do this in the FORWARD path and not the POST_ROUTING
4425                  * path because we want to make sure we apply the necessary
4426                  * labeling before IPsec is applied so we can leverage AH
4427                  * protection */
4428                 if (selinux_netlbl_skbuff_setsid(skb, family, peer_sid) != 0)
4429                         return NF_DROP;
4430
4431         return NF_ACCEPT;
4432 }
4433
4434 static unsigned int selinux_ipv4_forward(unsigned int hooknum,
4435                                          struct sk_buff *skb,
4436                                          const struct net_device *in,
4437                                          const struct net_device *out,
4438                                          int (*okfn)(struct sk_buff *))
4439 {
4440         return selinux_ip_forward(skb, in->ifindex, PF_INET);
4441 }
4442
4443 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
4444 static unsigned int selinux_ipv6_forward(unsigned int hooknum,
4445                                          struct sk_buff *skb,
4446                                          const struct net_device *in,
4447                                          const struct net_device *out,
4448                                          int (*okfn)(struct sk_buff *))
4449 {
4450         return selinux_ip_forward(skb, in->ifindex, PF_INET6);
4451 }
4452 #endif  /* IPV6 */
4453
4454 static unsigned int selinux_ip_output(struct sk_buff *skb,
4455                                       u16 family)
4456 {
4457         u32 sid;
4458
4459         if (!netlbl_enabled())
4460                 return NF_ACCEPT;
4461
4462         /* we do this in the LOCAL_OUT path and not the POST_ROUTING path
4463          * because we want to make sure we apply the necessary labeling
4464          * before IPsec is applied so we can leverage AH protection */
4465         if (skb->sk) {
4466                 struct sk_security_struct *sksec = skb->sk->sk_security;
4467                 sid = sksec->sid;
4468         } else
4469                 sid = SECINITSID_KERNEL;
4470         if (selinux_netlbl_skbuff_setsid(skb, family, sid) != 0)
4471                 return NF_DROP;
4472
4473         return NF_ACCEPT;
4474 }
4475
4476 static unsigned int selinux_ipv4_output(unsigned int hooknum,
4477                                         struct sk_buff *skb,
4478                                         const struct net_device *in,
4479                                         const struct net_device *out,
4480                                         int (*okfn)(struct sk_buff *))
4481 {
4482         return selinux_ip_output(skb, PF_INET);
4483 }
4484
4485 static unsigned int selinux_ip_postroute_compat(struct sk_buff *skb,
4486                                                 int ifindex,
4487                                                 u16 family)
4488 {
4489         struct sock *sk = skb->sk;
4490         struct sk_security_struct *sksec;
4491         struct common_audit_data ad;
4492         char *addrp;
4493         u8 proto;
4494
4495         if (sk == NULL)
4496                 return NF_ACCEPT;
4497         sksec = sk->sk_security;
4498
4499         COMMON_AUDIT_DATA_INIT(&ad, NET);
4500         ad.u.net.netif = ifindex;
4501         ad.u.net.family = family;
4502         if (selinux_parse_skb(skb, &ad, &addrp, 0, &proto))
4503                 return NF_DROP;
4504
4505         if (selinux_secmark_enabled())
4506                 if (avc_has_perm(sksec->sid, skb->secmark,
4507                                  SECCLASS_PACKET, PACKET__SEND, &ad))
4508                         return NF_DROP;
4509
4510         if (selinux_policycap_netpeer)
4511                 if (selinux_xfrm_postroute_last(sksec->sid, skb, &ad, proto))
4512                         return NF_DROP;
4513
4514         return NF_ACCEPT;
4515 }
4516
4517 static unsigned int selinux_ip_postroute(struct sk_buff *skb, int ifindex,
4518                                          u16 family)
4519 {
4520         u32 secmark_perm;
4521         u32 peer_sid;
4522         struct sock *sk;
4523         struct common_audit_data ad;
4524         char *addrp;
4525         u8 secmark_active;
4526         u8 peerlbl_active;
4527
4528         /* If any sort of compatibility mode is enabled then handoff processing
4529          * to the selinux_ip_postroute_compat() function to deal with the
4530          * special handling.  We do this in an attempt to keep this function
4531          * as fast and as clean as possible. */
4532         if (!selinux_policycap_netpeer)
4533                 return selinux_ip_postroute_compat(skb, ifindex, family);
4534 #ifdef CONFIG_XFRM
4535         /* If skb->dst->xfrm is non-NULL then the packet is undergoing an IPsec
4536          * packet transformation so allow the packet to pass without any checks
4537          * since we'll have another chance to perform access control checks
4538          * when the packet is on it's final way out.
4539          * NOTE: there appear to be some IPv6 multicast cases where skb->dst
4540          *       is NULL, in this case go ahead and apply access control. */
4541         if (skb_dst(skb) != NULL && skb_dst(skb)->xfrm != NULL)
4542                 return NF_ACCEPT;
4543 #endif
4544         secmark_active = selinux_secmark_enabled();
4545         peerlbl_active = netlbl_enabled() || selinux_xfrm_enabled();
4546         if (!secmark_active && !peerlbl_active)
4547                 return NF_ACCEPT;
4548
4549         /* if the packet is being forwarded then get the peer label from the
4550          * packet itself; otherwise check to see if it is from a local
4551          * application or the kernel, if from an application get the peer label
4552          * from the sending socket, otherwise use the kernel's sid */
4553         sk = skb->sk;
4554         if (sk == NULL) {
4555                 switch (family) {
4556                 case PF_INET:
4557                         if (IPCB(skb)->flags & IPSKB_FORWARDED)
4558                                 secmark_perm = PACKET__FORWARD_OUT;
4559                         else
4560                                 secmark_perm = PACKET__SEND;
4561                         break;
4562                 case PF_INET6:
4563                         if (IP6CB(skb)->flags & IP6SKB_FORWARDED)
4564                                 secmark_perm = PACKET__FORWARD_OUT;
4565                         else
4566                                 secmark_perm = PACKET__SEND;
4567                         break;
4568                 default:
4569                         return NF_DROP;
4570                 }
4571                 if (secmark_perm == PACKET__FORWARD_OUT) {
4572                         if (selinux_skb_peerlbl_sid(skb, family, &peer_sid))
4573                                 return NF_DROP;
4574                 } else
4575                         peer_sid = SECINITSID_KERNEL;
4576         } else {
4577                 struct sk_security_struct *sksec = sk->sk_security;
4578                 peer_sid = sksec->sid;
4579                 secmark_perm = PACKET__SEND;
4580         }
4581
4582         COMMON_AUDIT_DATA_INIT(&ad, NET);
4583         ad.u.net.netif = ifindex;
4584         ad.u.net.family = family;
4585         if (selinux_parse_skb(skb, &ad, &addrp, 0, NULL))
4586                 return NF_DROP;
4587
4588         if (secmark_active)
4589                 if (avc_has_perm(peer_sid, skb->secmark,
4590                                  SECCLASS_PACKET, secmark_perm, &ad))
4591                         return NF_DROP;
4592
4593         if (peerlbl_active) {
4594                 u32 if_sid;
4595                 u32 node_sid;
4596
4597                 if (sel_netif_sid(ifindex, &if_sid))
4598                         return NF_DROP;
4599                 if (avc_has_perm(peer_sid, if_sid,
4600                                  SECCLASS_NETIF, NETIF__EGRESS, &ad))
4601                         return NF_DROP;
4602
4603                 if (sel_netnode_sid(addrp, family, &node_sid))
4604                         return NF_DROP;
4605                 if (avc_has_perm(peer_sid, node_sid,
4606                                  SECCLASS_NODE, NODE__SENDTO, &ad))
4607                         return NF_DROP;
4608         }
4609
4610         return NF_ACCEPT;
4611 }
4612
4613 static unsigned int selinux_ipv4_postroute(unsigned int hooknum,
4614                                            struct sk_buff *skb,
4615                                            const struct net_device *in,
4616                                            const struct net_device *out,
4617                                            int (*okfn)(struct sk_buff *))
4618 {
4619         return selinux_ip_postroute(skb, out->ifindex, PF_INET);
4620 }
4621
4622 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
4623 static unsigned int selinux_ipv6_postroute(unsigned int hooknum,
4624                                            struct sk_buff *skb,
4625                                            const struct net_device *in,
4626                                            const struct net_device *out,
4627                                            int (*okfn)(struct sk_buff *))
4628 {
4629         return selinux_ip_postroute(skb, out->ifindex, PF_INET6);
4630 }
4631 #endif  /* IPV6 */
4632
4633 #endif  /* CONFIG_NETFILTER */
4634
4635 static int selinux_netlink_send(struct sock *sk, struct sk_buff *skb)
4636 {
4637         int err;
4638
4639         err = cap_netlink_send(sk, skb);
4640         if (err)
4641                 return err;
4642
4643         return selinux_nlmsg_perm(sk, skb);
4644 }
4645
4646 static int selinux_netlink_recv(struct sk_buff *skb, int capability)
4647 {
4648         int err;
4649         struct common_audit_data ad;
4650
4651         err = cap_netlink_recv(skb, capability);
4652         if (err)
4653                 return err;
4654
4655         COMMON_AUDIT_DATA_INIT(&ad, CAP);
4656         ad.u.cap = capability;
4657
4658         return avc_has_perm(NETLINK_CB(skb).sid, NETLINK_CB(skb).sid,
4659                             SECCLASS_CAPABILITY, CAP_TO_MASK(capability), &ad);
4660 }
4661
4662 static int ipc_alloc_security(struct task_struct *task,
4663                               struct kern_ipc_perm *perm,
4664                               u16 sclass)
4665 {
4666         struct ipc_security_struct *isec;
4667         u32 sid;
4668
4669         isec = kzalloc(sizeof(struct ipc_security_struct), GFP_KERNEL);
4670         if (!isec)
4671                 return -ENOMEM;
4672
4673         sid = task_sid(task);
4674         isec->sclass = sclass;
4675         isec->sid = sid;
4676         perm->security = isec;
4677
4678         return 0;
4679 }
4680
4681 static void ipc_free_security(struct kern_ipc_perm *perm)
4682 {
4683         struct ipc_security_struct *isec = perm->security;
4684         perm->security = NULL;
4685         kfree(isec);
4686 }
4687
4688 static int msg_msg_alloc_security(struct msg_msg *msg)
4689 {
4690         struct msg_security_struct *msec;
4691
4692         msec = kzalloc(sizeof(struct msg_security_struct), GFP_KERNEL);
4693         if (!msec)
4694                 return -ENOMEM;
4695
4696         msec->sid = SECINITSID_UNLABELED;
4697         msg->security = msec;
4698
4699         return 0;
4700 }
4701
4702 static void msg_msg_free_security(struct msg_msg *msg)
4703 {
4704         struct msg_security_struct *msec = msg->security;
4705
4706         msg->security = NULL;
4707         kfree(msec);
4708 }
4709
4710 static int ipc_has_perm(struct kern_ipc_perm *ipc_perms,
4711                         u32 perms)
4712 {
4713         struct ipc_security_struct *isec;
4714         struct common_audit_data ad;
4715         u32 sid = current_sid();
4716
4717         isec = ipc_perms->security;
4718
4719         COMMON_AUDIT_DATA_INIT(&ad, IPC);
4720         ad.u.ipc_id = ipc_perms->key;
4721
4722         return avc_has_perm(sid, isec->sid, isec->sclass, perms, &ad);
4723 }
4724
4725 static int selinux_msg_msg_alloc_security(struct msg_msg *msg)
4726 {
4727         return msg_msg_alloc_security(msg);
4728 }
4729
4730 static void selinux_msg_msg_free_security(struct msg_msg *msg)
4731 {
4732         msg_msg_free_security(msg);
4733 }
4734
4735 /* message queue security operations */
4736 static int selinux_msg_queue_alloc_security(struct msg_queue *msq)
4737 {
4738         struct ipc_security_struct *isec;
4739         struct common_audit_data ad;
4740         u32 sid = current_sid();
4741         int rc;
4742
4743         rc = ipc_alloc_security(current, &msq->q_perm, SECCLASS_MSGQ);
4744         if (rc)
4745                 return rc;
4746
4747         isec = msq->q_perm.security;
4748
4749         COMMON_AUDIT_DATA_INIT(&ad, IPC);
4750         ad.u.ipc_id = msq->q_perm.key;
4751
4752         rc = avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
4753                           MSGQ__CREATE, &ad);
4754         if (rc) {
4755                 ipc_free_security(&msq->q_perm);
4756                 return rc;
4757         }
4758         return 0;
4759 }
4760
4761 static void selinux_msg_queue_free_security(struct msg_queue *msq)
4762 {
4763         ipc_free_security(&msq->q_perm);
4764 }
4765
4766 static int selinux_msg_queue_associate(struct msg_queue *msq, int msqflg)
4767 {
4768         struct ipc_security_struct *isec;
4769         struct common_audit_data ad;
4770         u32 sid = current_sid();
4771
4772         isec = msq->q_perm.security;
4773
4774         COMMON_AUDIT_DATA_INIT(&ad, IPC);
4775         ad.u.ipc_id = msq->q_perm.key;
4776
4777         return avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
4778                             MSGQ__ASSOCIATE, &ad);
4779 }
4780
4781 static int selinux_msg_queue_msgctl(struct msg_queue *msq, int cmd)
4782 {
4783         int err;
4784         int perms;
4785
4786         switch (cmd) {
4787         case IPC_INFO:
4788         case MSG_INFO:
4789                 /* No specific object, just general system-wide information. */
4790                 return task_has_system(current, SYSTEM__IPC_INFO);
4791         case IPC_STAT:
4792         case MSG_STAT:
4793                 perms = MSGQ__GETATTR | MSGQ__ASSOCIATE;
4794                 break;
4795         case IPC_SET:
4796                 perms = MSGQ__SETATTR;
4797                 break;
4798         case IPC_RMID:
4799                 perms = MSGQ__DESTROY;
4800                 break;
4801         default:
4802                 return 0;
4803         }
4804
4805         err = ipc_has_perm(&msq->q_perm, perms);
4806         return err;
4807 }
4808
4809 static int selinux_msg_queue_msgsnd(struct msg_queue *msq, struct msg_msg *msg, int msqflg)
4810 {
4811         struct ipc_security_struct *isec;
4812         struct msg_security_struct *msec;
4813         struct common_audit_data ad;
4814         u32 sid = current_sid();
4815         int rc;
4816
4817         isec = msq->q_perm.security;
4818         msec = msg->security;
4819
4820         /*
4821          * First time through, need to assign label to the message
4822          */
4823         if (msec->sid == SECINITSID_UNLABELED) {
4824                 /*
4825                  * Compute new sid based on current process and
4826                  * message queue this message will be stored in
4827                  */
4828                 rc = security_transition_sid(sid, isec->sid, SECCLASS_MSG,
4829                                              &msec->sid);
4830                 if (rc)
4831                         return rc;
4832         }
4833
4834         COMMON_AUDIT_DATA_INIT(&ad, IPC);
4835         ad.u.ipc_id = msq->q_perm.key;
4836
4837         /* Can this process write to the queue? */
4838         rc = avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
4839                           MSGQ__WRITE, &ad);
4840         if (!rc)
4841                 /* Can this process send the message */
4842                 rc = avc_has_perm(sid, msec->sid, SECCLASS_MSG,
4843                                   MSG__SEND, &ad);
4844         if (!rc)
4845                 /* Can the message be put in the queue? */
4846                 rc = avc_has_perm(msec->sid, isec->sid, SECCLASS_MSGQ,
4847                                   MSGQ__ENQUEUE, &ad);
4848
4849         return rc;
4850 }
4851
4852 static int selinux_msg_queue_msgrcv(struct msg_queue *msq, struct msg_msg *msg,
4853                                     struct task_struct *target,
4854                                     long type, int mode)
4855 {
4856         struct ipc_security_struct *isec;
4857         struct msg_security_struct *msec;
4858         struct common_audit_data ad;
4859         u32 sid = task_sid(target);
4860         int rc;
4861
4862         isec = msq->q_perm.security;
4863         msec = msg->security;
4864
4865         COMMON_AUDIT_DATA_INIT(&ad, IPC);
4866         ad.u.ipc_id = msq->q_perm.key;
4867
4868         rc = avc_has_perm(sid, isec->sid,
4869                           SECCLASS_MSGQ, MSGQ__READ, &ad);
4870         if (!rc)
4871                 rc = avc_has_perm(sid, msec->sid,
4872                                   SECCLASS_MSG, MSG__RECEIVE, &ad);
4873         return rc;
4874 }
4875
4876 /* Shared Memory security operations */
4877 static int selinux_shm_alloc_security(struct shmid_kernel *shp)
4878 {
4879         struct ipc_security_struct *isec;
4880         struct common_audit_data ad;
4881         u32 sid = current_sid();
4882         int rc;
4883
4884         rc = ipc_alloc_security(current, &shp->shm_perm, SECCLASS_SHM);
4885         if (rc)
4886                 return rc;
4887
4888         isec = shp->shm_perm.security;
4889
4890         COMMON_AUDIT_DATA_INIT(&ad, IPC);
4891         ad.u.ipc_id = shp->shm_perm.key;
4892
4893         rc = avc_has_perm(sid, isec->sid, SECCLASS_SHM,
4894                           SHM__CREATE, &ad);
4895         if (rc) {
4896                 ipc_free_security(&shp->shm_perm);
4897                 return rc;
4898         }
4899         return 0;
4900 }
4901
4902 static void selinux_shm_free_security(struct shmid_kernel *shp)
4903 {
4904         ipc_free_security(&shp->shm_perm);
4905 }
4906
4907 static int selinux_shm_associate(struct shmid_kernel *shp, int shmflg)
4908 {
4909         struct ipc_security_struct *isec;
4910         struct common_audit_data ad;
4911         u32 sid = current_sid();
4912
4913         isec = shp->shm_perm.security;
4914
4915         COMMON_AUDIT_DATA_INIT(&ad, IPC);
4916         ad.u.ipc_id = shp->shm_perm.key;
4917
4918         return avc_has_perm(sid, isec->sid, SECCLASS_SHM,
4919                             SHM__ASSOCIATE, &ad);
4920 }
4921
4922 /* Note, at this point, shp is locked down */
4923 static int selinux_shm_shmctl(struct shmid_kernel *shp, int cmd)
4924 {
4925         int perms;
4926         int err;
4927
4928         switch (cmd) {
4929         case IPC_INFO:
4930         case SHM_INFO:
4931                 /* No specific object, just general system-wide information. */
4932                 return task_has_system(current, SYSTEM__IPC_INFO);
4933         case IPC_STAT:
4934         case SHM_STAT:
4935                 perms = SHM__GETATTR | SHM__ASSOCIATE;
4936                 break;
4937         case IPC_SET:
4938                 perms = SHM__SETATTR;
4939                 break;
4940         case SHM_LOCK:
4941         case SHM_UNLOCK:
4942                 perms = SHM__LOCK;
4943                 break;
4944         case IPC_RMID:
4945                 perms = SHM__DESTROY;
4946                 break;
4947         default:
4948                 return 0;
4949         }
4950
4951         err = ipc_has_perm(&shp->shm_perm, perms);
4952         return err;
4953 }
4954
4955 static int selinux_shm_shmat(struct shmid_kernel *shp,
4956                              char __user *shmaddr, int shmflg)
4957 {
4958         u32 perms;
4959
4960         if (shmflg & SHM_RDONLY)
4961                 perms = SHM__READ;
4962         else
4963                 perms = SHM__READ | SHM__WRITE;
4964
4965         return ipc_has_perm(&shp->shm_perm, perms);
4966 }
4967
4968 /* Semaphore security operations */
4969 static int selinux_sem_alloc_security(struct sem_array *sma)
4970 {
4971         struct ipc_security_struct *isec;
4972         struct common_audit_data ad;
4973         u32 sid = current_sid();
4974         int rc;
4975
4976         rc = ipc_alloc_security(current, &sma->sem_perm, SECCLASS_SEM);
4977         if (rc)
4978                 return rc;
4979
4980         isec = sma->sem_perm.security;
4981
4982         COMMON_AUDIT_DATA_INIT(&ad, IPC);
4983         ad.u.ipc_id = sma->sem_perm.key;
4984
4985         rc = avc_has_perm(sid, isec->sid, SECCLASS_SEM,
4986                           SEM__CREATE, &ad);
4987         if (rc) {
4988                 ipc_free_security(&sma->sem_perm);
4989                 return rc;
4990         }
4991         return 0;
4992 }
4993
4994 static void selinux_sem_free_security(struct sem_array *sma)
4995 {
4996         ipc_free_security(&sma->sem_perm);
4997 }
4998
4999 static int selinux_sem_associate(struct sem_array *sma, int semflg)
5000 {
5001         struct ipc_security_struct *isec;
5002         struct common_audit_data ad;
5003         u32 sid = current_sid();
5004
5005         isec = sma->sem_perm.security;
5006
5007         COMMON_AUDIT_DATA_INIT(&ad, IPC);
5008         ad.u.ipc_id = sma->sem_perm.key;
5009
5010         return avc_has_perm(sid, isec->sid, SECCLASS_SEM,
5011                             SEM__ASSOCIATE, &ad);
5012 }
5013
5014 /* Note, at this point, sma is locked down */
5015 static int selinux_sem_semctl(struct sem_array *sma, int cmd)
5016 {
5017         int err;
5018         u32 perms;
5019
5020         switch (cmd) {
5021         case IPC_INFO:
5022         case SEM_INFO:
5023                 /* No specific object, just general system-wide information. */
5024                 return task_has_system(current, SYSTEM__IPC_INFO);
5025         case GETPID:
5026         case GETNCNT:
5027         case GETZCNT:
5028                 perms = SEM__GETATTR;
5029                 break;
5030         case GETVAL:
5031         case GETALL:
5032                 perms = SEM__READ;
5033                 break;
5034         case SETVAL:
5035         case SETALL:
5036                 perms = SEM__WRITE;
5037                 break;
5038         case IPC_RMID:
5039                 perms = SEM__DESTROY;
5040                 break;
5041         case IPC_SET:
5042                 perms = SEM__SETATTR;
5043                 break;
5044         case IPC_STAT:
5045         case SEM_STAT:
5046                 perms = SEM__GETATTR | SEM__ASSOCIATE;
5047                 break;
5048         default:
5049                 return 0;
5050         }
5051
5052         err = ipc_has_perm(&sma->sem_perm, perms);
5053         return err;
5054 }
5055
5056 static int selinux_sem_semop(struct sem_array *sma,
5057                              struct sembuf *sops, unsigned nsops, int alter)
5058 {
5059         u32 perms;
5060
5061         if (alter)
5062                 perms = SEM__READ | SEM__WRITE;
5063         else
5064                 perms = SEM__READ;
5065
5066         return ipc_has_perm(&sma->sem_perm, perms);
5067 }
5068
5069 static int selinux_ipc_permission(struct kern_ipc_perm *ipcp, short flag)
5070 {
5071         u32 av = 0;
5072
5073         av = 0;
5074         if (flag & S_IRUGO)
5075                 av |= IPC__UNIX_READ;
5076         if (flag & S_IWUGO)
5077                 av |= IPC__UNIX_WRITE;
5078
5079         if (av == 0)
5080                 return 0;
5081
5082         return ipc_has_perm(ipcp, av);
5083 }
5084
5085 static void selinux_ipc_getsecid(struct kern_ipc_perm *ipcp, u32 *secid)
5086 {
5087         struct ipc_security_struct *isec = ipcp->security;
5088         *secid = isec->sid;
5089 }
5090
5091 static void selinux_d_instantiate(struct dentry *dentry, struct inode *inode)
5092 {
5093         if (inode)
5094                 inode_doinit_with_dentry(inode, dentry);
5095 }
5096
5097 static int selinux_getprocattr(struct task_struct *p,
5098                                char *name, char **value)
5099 {
5100         const struct task_security_struct *__tsec;
5101         u32 sid;
5102         int error;
5103         unsigned len;
5104
5105         if (current != p) {
5106                 error = current_has_perm(p, PROCESS__GETATTR);
5107                 if (error)
5108                         return error;
5109         }
5110
5111         rcu_read_lock();
5112         __tsec = __task_cred(p)->security;
5113
5114         if (!strcmp(name, "current"))
5115                 sid = __tsec->sid;
5116         else if (!strcmp(name, "prev"))
5117                 sid = __tsec->osid;
5118         else if (!strcmp(name, "exec"))
5119                 sid = __tsec->exec_sid;
5120         else if (!strcmp(name, "fscreate"))
5121                 sid = __tsec->create_sid;
5122         else if (!strcmp(name, "keycreate"))
5123                 sid = __tsec->keycreate_sid;
5124         else if (!strcmp(name, "sockcreate"))
5125                 sid = __tsec->sockcreate_sid;
5126         else
5127                 goto invalid;
5128         rcu_read_unlock();
5129
5130         if (!sid)
5131                 return 0;
5132
5133         error = security_sid_to_context(sid, value, &len);
5134         if (error)
5135                 return error;
5136         return len;
5137
5138 invalid:
5139         rcu_read_unlock();
5140         return -EINVAL;
5141 }
5142
5143 static int selinux_setprocattr(struct task_struct *p,
5144                                char *name, void *value, size_t size)
5145 {
5146         struct task_security_struct *tsec;
5147         struct task_struct *tracer;
5148         struct cred *new;
5149         u32 sid = 0, ptsid;
5150         int error;
5151         char *str = value;
5152
5153         if (current != p) {
5154                 /* SELinux only allows a process to change its own
5155                    security attributes. */
5156                 return -EACCES;
5157         }
5158
5159         /*
5160          * Basic control over ability to set these attributes at all.
5161          * current == p, but we'll pass them separately in case the
5162          * above restriction is ever removed.
5163          */
5164         if (!strcmp(name, "exec"))
5165                 error = current_has_perm(p, PROCESS__SETEXEC);
5166         else if (!strcmp(name, "fscreate"))
5167                 error = current_has_perm(p, PROCESS__SETFSCREATE);
5168         else if (!strcmp(name, "keycreate"))
5169                 error = current_has_perm(p, PROCESS__SETKEYCREATE);
5170         else if (!strcmp(name, "sockcreate"))
5171                 error = current_has_perm(p, PROCESS__SETSOCKCREATE);
5172         else if (!strcmp(name, "current"))
5173                 error = current_has_perm(p, PROCESS__SETCURRENT);
5174         else
5175                 error = -EINVAL;
5176         if (error)
5177                 return error;
5178
5179         /* Obtain a SID for the context, if one was specified. */
5180         if (size && str[1] && str[1] != '\n') {
5181                 if (str[size-1] == '\n') {
5182                         str[size-1] = 0;
5183                         size--;
5184                 }
5185                 error = security_context_to_sid(value, size, &sid);
5186                 if (error == -EINVAL && !strcmp(name, "fscreate")) {
5187                         if (!capable(CAP_MAC_ADMIN))
5188                                 return error;
5189                         error = security_context_to_sid_force(value, size,
5190                                                               &sid);
5191                 }
5192                 if (error)
5193                         return error;
5194         }
5195
5196         new = prepare_creds();
5197         if (!new)
5198                 return -ENOMEM;
5199
5200         /* Permission checking based on the specified context is
5201            performed during the actual operation (execve,
5202            open/mkdir/...), when we know the full context of the
5203            operation.  See selinux_bprm_set_creds for the execve
5204            checks and may_create for the file creation checks. The
5205            operation will then fail if the context is not permitted. */
5206         tsec = new->security;
5207         if (!strcmp(name, "exec")) {
5208                 tsec->exec_sid = sid;
5209         } else if (!strcmp(name, "fscreate")) {
5210                 tsec->create_sid = sid;
5211         } else if (!strcmp(name, "keycreate")) {
5212                 error = may_create_key(sid, p);
5213                 if (error)
5214                         goto abort_change;
5215                 tsec->keycreate_sid = sid;
5216         } else if (!strcmp(name, "sockcreate")) {
5217                 tsec->sockcreate_sid = sid;
5218         } else if (!strcmp(name, "current")) {
5219                 error = -EINVAL;
5220                 if (sid == 0)
5221                         goto abort_change;
5222
5223                 /* Only allow single threaded processes to change context */
5224                 error = -EPERM;
5225                 if (!current_is_single_threaded()) {
5226                         error = security_bounded_transition(tsec->sid, sid);
5227                         if (error)
5228                                 goto abort_change;
5229                 }
5230
5231                 /* Check permissions for the transition. */
5232                 error = avc_has_perm(tsec->sid, sid, SECCLASS_PROCESS,
5233                                      PROCESS__DYNTRANSITION, NULL);
5234                 if (error)
5235                         goto abort_change;
5236
5237                 /* Check for ptracing, and update the task SID if ok.
5238                    Otherwise, leave SID unchanged and fail. */
5239                 ptsid = 0;
5240                 task_lock(p);
5241                 tracer = tracehook_tracer_task(p);
5242                 if (tracer)
5243                         ptsid = task_sid(tracer);
5244                 task_unlock(p);
5245
5246                 if (tracer) {
5247                         error = avc_has_perm(ptsid, sid, SECCLASS_PROCESS,
5248                                              PROCESS__PTRACE, NULL);
5249                         if (error)
5250                                 goto abort_change;
5251                 }
5252
5253                 tsec->sid = sid;
5254         } else {
5255                 error = -EINVAL;
5256                 goto abort_change;
5257         }
5258
5259         commit_creds(new);
5260         return size;
5261
5262 abort_change:
5263         abort_creds(new);
5264         return error;
5265 }
5266
5267 static int selinux_secid_to_secctx(u32 secid, char **secdata, u32 *seclen)
5268 {
5269         return security_sid_to_context(secid, secdata, seclen);
5270 }
5271
5272 static int selinux_secctx_to_secid(const char *secdata, u32 seclen, u32 *secid)
5273 {
5274         return security_context_to_sid(secdata, seclen, secid);
5275 }
5276
5277 static void selinux_release_secctx(char *secdata, u32 seclen)
5278 {
5279         kfree(secdata);
5280 }
5281
5282 /*
5283  *      called with inode->i_mutex locked
5284  */
5285 static int selinux_inode_notifysecctx(struct inode *inode, void *ctx, u32 ctxlen)
5286 {
5287         return selinux_inode_setsecurity(inode, XATTR_SELINUX_SUFFIX, ctx, ctxlen, 0);
5288 }
5289
5290 /*
5291  *      called with inode->i_mutex locked
5292  */
5293 static int selinux_inode_setsecctx(struct dentry *dentry, void *ctx, u32 ctxlen)
5294 {
5295         return __vfs_setxattr_noperm(dentry, XATTR_NAME_SELINUX, ctx, ctxlen, 0);
5296 }
5297
5298 static int selinux_inode_getsecctx(struct inode *inode, void **ctx, u32 *ctxlen)
5299 {
5300         int len = 0;
5301         len = selinux_inode_getsecurity(inode, XATTR_SELINUX_SUFFIX,
5302                                                 ctx, true);
5303         if (len < 0)
5304                 return len;
5305         *ctxlen = len;
5306         return 0;
5307 }
5308 #ifdef CONFIG_KEYS
5309
5310 static int selinux_key_alloc(struct key *k, const struct cred *cred,
5311                              unsigned long flags)
5312 {
5313         const struct task_security_struct *tsec;
5314         struct key_security_struct *ksec;
5315
5316         ksec = kzalloc(sizeof(struct key_security_struct), GFP_KERNEL);
5317         if (!ksec)
5318                 return -ENOMEM;
5319
5320         tsec = cred->security;
5321         if (tsec->keycreate_sid)
5322                 ksec->sid = tsec->keycreate_sid;
5323         else
5324                 ksec->sid = tsec->sid;
5325
5326         k->security = ksec;
5327         return 0;
5328 }
5329
5330 static void selinux_key_free(struct key *k)
5331 {
5332         struct key_security_struct *ksec = k->security;
5333
5334         k->security = NULL;
5335         kfree(ksec);
5336 }
5337
5338 static int selinux_key_permission(key_ref_t key_ref,
5339                                   const struct cred *cred,
5340                                   key_perm_t perm)
5341 {
5342         struct key *key;
5343         struct key_security_struct *ksec;
5344         u32 sid;
5345
5346         /* if no specific permissions are requested, we skip the
5347            permission check. No serious, additional covert channels
5348            appear to be created. */
5349         if (perm == 0)
5350                 return 0;
5351
5352         sid = cred_sid(cred);
5353
5354         key = key_ref_to_ptr(key_ref);
5355         ksec = key->security;
5356
5357         return avc_has_perm(sid, ksec->sid, SECCLASS_KEY, perm, NULL);
5358 }
5359
5360 static int selinux_key_getsecurity(struct key *key, char **_buffer)
5361 {
5362         struct key_security_struct *ksec = key->security;
5363         char *context = NULL;
5364         unsigned len;
5365         int rc;
5366
5367         rc = security_sid_to_context(ksec->sid, &context, &len);
5368         if (!rc)
5369                 rc = len;
5370         *_buffer = context;
5371         return rc;
5372 }
5373
5374 #endif
5375
5376 static struct security_operations selinux_ops = {
5377         .name =                         "selinux",
5378
5379         .ptrace_access_check =          selinux_ptrace_access_check,
5380         .ptrace_traceme =               selinux_ptrace_traceme,
5381         .capget =                       selinux_capget,
5382         .capset =                       selinux_capset,
5383         .sysctl =                       selinux_sysctl,
5384         .capable =                      selinux_capable,
5385         .quotactl =                     selinux_quotactl,
5386         .quota_on =                     selinux_quota_on,
5387         .syslog =                       selinux_syslog,
5388         .vm_enough_memory =             selinux_vm_enough_memory,
5389
5390         .netlink_send =                 selinux_netlink_send,
5391         .netlink_recv =                 selinux_netlink_recv,
5392
5393         .bprm_set_creds =               selinux_bprm_set_creds,
5394         .bprm_committing_creds =        selinux_bprm_committing_creds,
5395         .bprm_committed_creds =         selinux_bprm_committed_creds,
5396         .bprm_secureexec =              selinux_bprm_secureexec,
5397
5398         .sb_alloc_security =            selinux_sb_alloc_security,
5399         .sb_free_security =             selinux_sb_free_security,
5400         .sb_copy_data =                 selinux_sb_copy_data,
5401         .sb_kern_mount =                selinux_sb_kern_mount,
5402         .sb_show_options =              selinux_sb_show_options,
5403         .sb_statfs =                    selinux_sb_statfs,
5404         .sb_mount =                     selinux_mount,
5405         .sb_umount =                    selinux_umount,
5406         .sb_set_mnt_opts =              selinux_set_mnt_opts,
5407         .sb_clone_mnt_opts =            selinux_sb_clone_mnt_opts,
5408         .sb_parse_opts_str =            selinux_parse_opts_str,
5409
5410
5411         .inode_alloc_security =         selinux_inode_alloc_security,
5412         .inode_free_security =          selinux_inode_free_security,
5413         .inode_init_security =          selinux_inode_init_security,
5414         .inode_create =                 selinux_inode_create,
5415         .inode_link =                   selinux_inode_link,
5416         .inode_unlink =                 selinux_inode_unlink,
5417         .inode_symlink =                selinux_inode_symlink,
5418         .inode_mkdir =                  selinux_inode_mkdir,
5419         .inode_rmdir =                  selinux_inode_rmdir,
5420         .inode_mknod =                  selinux_inode_mknod,
5421         .inode_rename =                 selinux_inode_rename,
5422         .inode_readlink =               selinux_inode_readlink,
5423         .inode_follow_link =            selinux_inode_follow_link,
5424         .inode_permission =             selinux_inode_permission,
5425         .inode_setattr =                selinux_inode_setattr,
5426         .inode_getattr =                selinux_inode_getattr,
5427         .inode_setxattr =               selinux_inode_setxattr,
5428         .inode_post_setxattr =          selinux_inode_post_setxattr,
5429         .inode_getxattr =               selinux_inode_getxattr,
5430         .inode_listxattr =              selinux_inode_listxattr,
5431         .inode_removexattr =            selinux_inode_removexattr,
5432         .inode_getsecurity =            selinux_inode_getsecurity,
5433         .inode_setsecurity =            selinux_inode_setsecurity,
5434         .inode_listsecurity =           selinux_inode_listsecurity,
5435         .inode_getsecid =               selinux_inode_getsecid,
5436
5437         .file_permission =              selinux_file_permission,
5438         .file_alloc_security =          selinux_file_alloc_security,
5439         .file_free_security =           selinux_file_free_security,
5440         .file_ioctl =                   selinux_file_ioctl,
5441         .file_mmap =                    selinux_file_mmap,
5442         .file_mprotect =                selinux_file_mprotect,
5443         .file_lock =                    selinux_file_lock,
5444         .file_fcntl =                   selinux_file_fcntl,
5445         .file_set_fowner =              selinux_file_set_fowner,
5446         .file_send_sigiotask =          selinux_file_send_sigiotask,
5447         .file_receive =                 selinux_file_receive,
5448
5449         .dentry_open =                  selinux_dentry_open,
5450
5451         .task_create =                  selinux_task_create,
5452         .cred_alloc_blank =             selinux_cred_alloc_blank,
5453         .cred_free =                    selinux_cred_free,
5454         .cred_prepare =                 selinux_cred_prepare,
5455         .cred_transfer =                selinux_cred_transfer,
5456         .kernel_act_as =                selinux_kernel_act_as,
5457         .kernel_create_files_as =       selinux_kernel_create_files_as,
5458         .kernel_module_request =        selinux_kernel_module_request,
5459         .task_setpgid =                 selinux_task_setpgid,
5460         .task_getpgid =                 selinux_task_getpgid,
5461         .task_getsid =                  selinux_task_getsid,
5462         .task_getsecid =                selinux_task_getsecid,
5463         .task_setnice =                 selinux_task_setnice,
5464         .task_setioprio =               selinux_task_setioprio,
5465         .task_getioprio =               selinux_task_getioprio,
5466         .task_setrlimit =               selinux_task_setrlimit,
5467         .task_setscheduler =            selinux_task_setscheduler,
5468         .task_getscheduler =            selinux_task_getscheduler,
5469         .task_movememory =              selinux_task_movememory,
5470         .task_kill =                    selinux_task_kill,
5471         .task_wait =                    selinux_task_wait,
5472         .task_to_inode =                selinux_task_to_inode,
5473
5474         .ipc_permission =               selinux_ipc_permission,
5475         .ipc_getsecid =                 selinux_ipc_getsecid,
5476
5477         .msg_msg_alloc_security =       selinux_msg_msg_alloc_security,
5478         .msg_msg_free_security =        selinux_msg_msg_free_security,
5479
5480         .msg_queue_alloc_security =     selinux_msg_queue_alloc_security,
5481         .msg_queue_free_security =      selinux_msg_queue_free_security,
5482         .msg_queue_associate =          selinux_msg_queue_associate,
5483         .msg_queue_msgctl =             selinux_msg_queue_msgctl,
5484         .msg_queue_msgsnd =             selinux_msg_queue_msgsnd,
5485         .msg_queue_msgrcv =             selinux_msg_queue_msgrcv,
5486
5487         .shm_alloc_security =           selinux_shm_alloc_security,
5488         .shm_free_security =            selinux_shm_free_security,
5489         .shm_associate =                selinux_shm_associate,
5490         .shm_shmctl =                   selinux_shm_shmctl,
5491         .shm_shmat =                    selinux_shm_shmat,
5492
5493         .sem_alloc_security =           selinux_sem_alloc_security,
5494         .sem_free_security =            selinux_sem_free_security,
5495         .sem_associate =                selinux_sem_associate,
5496         .sem_semctl =                   selinux_sem_semctl,
5497         .sem_semop =                    selinux_sem_semop,
5498
5499         .d_instantiate =                selinux_d_instantiate,
5500
5501         .getprocattr =                  selinux_getprocattr,
5502         .setprocattr =                  selinux_setprocattr,
5503
5504         .secid_to_secctx =              selinux_secid_to_secctx,
5505         .secctx_to_secid =              selinux_secctx_to_secid,
5506         .release_secctx =               selinux_release_secctx,
5507         .inode_notifysecctx =           selinux_inode_notifysecctx,
5508         .inode_setsecctx =              selinux_inode_setsecctx,
5509         .inode_getsecctx =              selinux_inode_getsecctx,
5510
5511         .unix_stream_connect =          selinux_socket_unix_stream_connect,
5512         .unix_may_send =                selinux_socket_unix_may_send,
5513
5514         .socket_create =                selinux_socket_create,
5515         .socket_post_create =           selinux_socket_post_create,
5516         .socket_bind =                  selinux_socket_bind,
5517         .socket_connect =               selinux_socket_connect,
5518         .socket_listen =                selinux_socket_listen,
5519         .socket_accept =                selinux_socket_accept,
5520         .socket_sendmsg =               selinux_socket_sendmsg,
5521         .socket_recvmsg =               selinux_socket_recvmsg,
5522         .socket_getsockname =           selinux_socket_getsockname,
5523         .socket_getpeername =           selinux_socket_getpeername,
5524         .socket_getsockopt =            selinux_socket_getsockopt,
5525         .socket_setsockopt =            selinux_socket_setsockopt,
5526         .socket_shutdown =              selinux_socket_shutdown,
5527         .socket_sock_rcv_skb =          selinux_socket_sock_rcv_skb,
5528         .socket_getpeersec_stream =     selinux_socket_getpeersec_stream,
5529         .socket_getpeersec_dgram =      selinux_socket_getpeersec_dgram,
5530         .sk_alloc_security =            selinux_sk_alloc_security,
5531         .sk_free_security =             selinux_sk_free_security,
5532         .sk_clone_security =            selinux_sk_clone_security,
5533         .sk_getsecid =                  selinux_sk_getsecid,
5534         .sock_graft =                   selinux_sock_graft,
5535         .inet_conn_request =            selinux_inet_conn_request,
5536         .inet_csk_clone =               selinux_inet_csk_clone,
5537         .inet_conn_established =        selinux_inet_conn_established,
5538         .req_classify_flow =            selinux_req_classify_flow,
5539         .tun_dev_create =               selinux_tun_dev_create,
5540         .tun_dev_post_create =          selinux_tun_dev_post_create,
5541         .tun_dev_attach =               selinux_tun_dev_attach,
5542
5543 #ifdef CONFIG_SECURITY_NETWORK_XFRM
5544         .xfrm_policy_alloc_security =   selinux_xfrm_policy_alloc,
5545         .xfrm_policy_clone_security =   selinux_xfrm_policy_clone,
5546         .xfrm_policy_free_security =    selinux_xfrm_policy_free,
5547         .xfrm_policy_delete_security =  selinux_xfrm_policy_delete,
5548         .xfrm_state_alloc_security =    selinux_xfrm_state_alloc,
5549         .xfrm_state_free_security =     selinux_xfrm_state_free,
5550         .xfrm_state_delete_security =   selinux_xfrm_state_delete,
5551         .xfrm_policy_lookup =           selinux_xfrm_policy_lookup,
5552         .xfrm_state_pol_flow_match =    selinux_xfrm_state_pol_flow_match,
5553         .xfrm_decode_session =          selinux_xfrm_decode_session,
5554 #endif
5555
5556 #ifdef CONFIG_KEYS
5557         .key_alloc =                    selinux_key_alloc,
5558         .key_free =                     selinux_key_free,
5559         .key_permission =               selinux_key_permission,
5560         .key_getsecurity =              selinux_key_getsecurity,
5561 #endif
5562
5563 #ifdef CONFIG_AUDIT
5564         .audit_rule_init =              selinux_audit_rule_init,
5565         .audit_rule_known =             selinux_audit_rule_known,
5566         .audit_rule_match =             selinux_audit_rule_match,
5567         .audit_rule_free =              selinux_audit_rule_free,
5568 #endif
5569 };
5570
5571 static __init int selinux_init(void)
5572 {
5573         if (!security_module_enable(&selinux_ops)) {
5574                 selinux_enabled = 0;
5575                 return 0;
5576         }
5577
5578         if (!selinux_enabled) {
5579                 printk(KERN_INFO "SELinux:  Disabled at boot.\n");
5580                 return 0;
5581         }
5582
5583         printk(KERN_INFO "SELinux:  Initializing.\n");
5584
5585         /* Set the security state for the initial task. */
5586         cred_init_security();
5587
5588         default_noexec = !(VM_DATA_DEFAULT_FLAGS & VM_EXEC);
5589
5590         sel_inode_cache = kmem_cache_create("selinux_inode_security",
5591                                             sizeof(struct inode_security_struct),
5592                                             0, SLAB_PANIC, NULL);
5593         avc_init();
5594
5595         if (register_security(&selinux_ops))
5596                 panic("SELinux: Unable to register with kernel.\n");
5597
5598         if (selinux_enforcing)
5599                 printk(KERN_DEBUG "SELinux:  Starting in enforcing mode\n");
5600         else
5601                 printk(KERN_DEBUG "SELinux:  Starting in permissive mode\n");
5602
5603         return 0;
5604 }
5605
5606 static void delayed_superblock_init(struct super_block *sb, void *unused)
5607 {
5608         superblock_doinit(sb, NULL);
5609 }
5610
5611 void selinux_complete_init(void)
5612 {
5613         printk(KERN_DEBUG "SELinux:  Completing initialization.\n");
5614
5615         /* Set up any superblocks initialized prior to the policy load. */
5616         printk(KERN_DEBUG "SELinux:  Setting up existing superblocks.\n");
5617         iterate_supers(delayed_superblock_init, NULL);
5618 }
5619
5620 /* SELinux requires early initialization in order to label
5621    all processes and objects when they are created. */
5622 security_initcall(selinux_init);
5623
5624 #if defined(CONFIG_NETFILTER)
5625
5626 static struct nf_hook_ops selinux_ipv4_ops[] = {
5627         {
5628                 .hook =         selinux_ipv4_postroute,
5629                 .owner =        THIS_MODULE,
5630                 .pf =           PF_INET,
5631                 .hooknum =      NF_INET_POST_ROUTING,
5632                 .priority =     NF_IP_PRI_SELINUX_LAST,
5633         },
5634         {
5635                 .hook =         selinux_ipv4_forward,
5636                 .owner =        THIS_MODULE,
5637                 .pf =           PF_INET,
5638                 .hooknum =      NF_INET_FORWARD,
5639                 .priority =     NF_IP_PRI_SELINUX_FIRST,
5640         },
5641         {
5642                 .hook =         selinux_ipv4_output,
5643                 .owner =        THIS_MODULE,
5644                 .pf =           PF_INET,
5645                 .hooknum =      NF_INET_LOCAL_OUT,
5646                 .priority =     NF_IP_PRI_SELINUX_FIRST,
5647         }
5648 };
5649
5650 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
5651
5652 static struct nf_hook_ops selinux_ipv6_ops[] = {
5653         {
5654                 .hook =         selinux_ipv6_postroute,
5655                 .owner =        THIS_MODULE,
5656                 .pf =           PF_INET6,
5657                 .hooknum =      NF_INET_POST_ROUTING,
5658                 .priority =     NF_IP6_PRI_SELINUX_LAST,
5659         },
5660         {
5661                 .hook =         selinux_ipv6_forward,
5662                 .owner =        THIS_MODULE,
5663                 .pf =           PF_INET6,
5664                 .hooknum =      NF_INET_FORWARD,
5665                 .priority =     NF_IP6_PRI_SELINUX_FIRST,
5666         }
5667 };
5668
5669 #endif  /* IPV6 */
5670
5671 static int __init selinux_nf_ip_init(void)
5672 {
5673         int err = 0;
5674
5675         if (!selinux_enabled)
5676                 goto out;
5677
5678         printk(KERN_DEBUG "SELinux:  Registering netfilter hooks\n");
5679
5680         err = nf_register_hooks(selinux_ipv4_ops, ARRAY_SIZE(selinux_ipv4_ops));
5681         if (err)
5682                 panic("SELinux: nf_register_hooks for IPv4: error %d\n", err);
5683
5684 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
5685         err = nf_register_hooks(selinux_ipv6_ops, ARRAY_SIZE(selinux_ipv6_ops));
5686         if (err)
5687                 panic("SELinux: nf_register_hooks for IPv6: error %d\n", err);
5688 #endif  /* IPV6 */
5689
5690 out:
5691         return err;
5692 }
5693
5694 __initcall(selinux_nf_ip_init);
5695
5696 #ifdef CONFIG_SECURITY_SELINUX_DISABLE
5697 static void selinux_nf_ip_exit(void)
5698 {
5699         printk(KERN_DEBUG "SELinux:  Unregistering netfilter hooks\n");
5700
5701         nf_unregister_hooks(selinux_ipv4_ops, ARRAY_SIZE(selinux_ipv4_ops));
5702 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
5703         nf_unregister_hooks(selinux_ipv6_ops, ARRAY_SIZE(selinux_ipv6_ops));
5704 #endif  /* IPV6 */
5705 }
5706 #endif
5707
5708 #else /* CONFIG_NETFILTER */
5709
5710 #ifdef CONFIG_SECURITY_SELINUX_DISABLE
5711 #define selinux_nf_ip_exit()
5712 #endif
5713
5714 #endif /* CONFIG_NETFILTER */
5715
5716 #ifdef CONFIG_SECURITY_SELINUX_DISABLE
5717 static int selinux_disabled;
5718
5719 int selinux_disable(void)
5720 {
5721         extern void exit_sel_fs(void);
5722
5723         if (ss_initialized) {
5724                 /* Not permitted after initial policy load. */
5725                 return -EINVAL;
5726         }
5727
5728         if (selinux_disabled) {
5729                 /* Only do this once. */
5730                 return -EINVAL;
5731         }
5732
5733         printk(KERN_INFO "SELinux:  Disabled at runtime.\n");
5734
5735         selinux_disabled = 1;
5736         selinux_enabled = 0;
5737
5738         reset_security_ops();
5739
5740         /* Try to destroy the avc node cache */
5741         avc_disable();
5742
5743         /* Unregister netfilter hooks. */
5744         selinux_nf_ip_exit();
5745
5746         /* Unregister selinuxfs. */
5747         exit_sel_fs();
5748
5749         return 0;
5750 }
5751 #endif