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   1 /*
   2  *  NSA Security-Enhanced Linux (SELinux) security module
   3  *
   4  *  This file contains the SELinux hook function implementations.
   5  *
   6  *  Authors:  Stephen Smalley, <sds@epoch.ncsc.mil>
   7  *            Chris Vance, <cvance@nai.com>
   8  *            Wayne Salamon, <wsalamon@nai.com>
   9  *            James Morris <jmorris@redhat.com>
  10  *
  11  *  Copyright (C) 2001,2002 Networks Associates Technology, Inc.
  12  *  Copyright (C) 2003-2008 Red Hat, Inc., James Morris <jmorris@redhat.com>
  13  *                                         Eric Paris <eparis@redhat.com>
  14  *  Copyright (C) 2004-2005 Trusted Computer Solutions, Inc.
  15  *                          <dgoeddel@trustedcs.com>
  16  *  Copyright (C) 2006, 2007 Hewlett-Packard Development Company, L.P.
  17  *              Paul Moore <paul.moore@hp.com>
  18  *  Copyright (C) 2007 Hitachi Software Engineering Co., Ltd.
  19  *                     Yuichi Nakamura <ynakam@hitachisoft.jp>
  20  *
  21  *      This program is free software; you can redistribute it and/or modify
  22  *      it under the terms of the GNU General Public License version 2,
  23  *      as published by the Free Software Foundation.
  24  */
  25
  26 #include <linux/init.h>
  27 #include <linux/kernel.h>
  28 #include <linux/tracehook.h>
  29 #include <linux/errno.h>
  30 #include <linux/sched.h>
  31 #include <linux/security.h>
  32 #include <linux/xattr.h>
  33 #include <linux/capability.h>
  34 #include <linux/unistd.h>
  35 #include <linux/mm.h>
  36 #include <linux/mman.h>
  37 #include <linux/slab.h>
  38 #include <linux/pagemap.h>
  39 #include <linux/swap.h>
  40 #include <linux/spinlock.h>
  41 #include <linux/syscalls.h>
  42 #include <linux/file.h>
  43 #include <linux/fdtable.h>
  44 #include <linux/namei.h>
  45 #include <linux/mount.h>
  46 #include <linux/proc_fs.h>
  47 #include <linux/netfilter_ipv4.h>
  48 #include <linux/netfilter_ipv6.h>
  49 #include <linux/tty.h>
  50 #include <net/icmp.h>
  51 #include <net/ip.h>             /* for local_port_range[] */
  52 #include <net/tcp.h>            /* struct or_callable used in sock_rcv_skb */
  53 #include <net/net_namespace.h>
  54 #include <net/netlabel.h>
  55 #include <linux/uaccess.h>
  56 #include <asm/ioctls.h>
  57 #include <asm/atomic.h>
  58 #include <linux/bitops.h>
  59 #include <linux/interrupt.h>
  60 #include <linux/netdevice.h>    /* for network interface checks */
  61 #include <linux/netlink.h>
  62 #include <linux/tcp.h>
  63 #include <linux/udp.h>
  64 #include <linux/dccp.h>
  65 #include <linux/quota.h>
  66 #include <linux/un.h>           /* for Unix socket types */
  67 #include <net/af_unix.h>        /* for Unix socket types */
  68 #include <linux/parser.h>
  69 #include <linux/nfs_mount.h>
  70 #include <net/ipv6.h>
  71 #include <linux/hugetlb.h>
  72 #include <linux/personality.h>
  73 #include <linux/sysctl.h>
  74 #include <linux/audit.h>
  75 #include <linux/string.h>
  76 #include <linux/selinux.h>
  77 #include <linux/mutex.h>
  78 #include <linux/posix-timers.h>
  79
  80 #include "avc.h"
  81 #include "objsec.h"
  82 #include "netif.h"
  83 #include "netnode.h"
  84 #include "netport.h"
  85 #include "xfrm.h"
  86 #include "netlabel.h"
  87 #include "audit.h"
  88
  89 #define XATTR_SELINUX_SUFFIX "selinux"
  90 #define XATTR_NAME_SELINUX XATTR_SECURITY_PREFIX XATTR_SELINUX_SUFFIX
  91
  92 #define NUM_SEL_MNT_OPTS 5
  93
  94 extern unsigned int policydb_loaded_version;
  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
 130 /*
 131  * Minimal support for a secondary security module,
 132  * just to allow the use of the capability module.
 133  */
 134 static struct security_operations *secondary_ops;
 135
 136 /* Lists of inode and superblock security structures initialized
 137    before the policy was loaded. */
 138 static LIST_HEAD(superblock_security_head);
 139 static DEFINE_SPINLOCK(sb_security_lock);
 140
 141 static struct kmem_cache *sel_inode_cache;
 142
 143 /**
 144  * selinux_secmark_enabled - Check to see if SECMARK is currently enabled
 145  *
 146  * Description:
 147  * This function checks the SECMARK reference counter to see if any SECMARK
 148  * targets are currently configured, if the reference counter is greater than
 149  * zero SECMARK is considered to be enabled.  Returns true (1) if SECMARK is
 150  * enabled, false (0) if SECMARK is disabled.
 151  *
 152  */
 153 static int selinux_secmark_enabled(void)
 154 {
 155         return (atomic_read(&selinux_secmark_refcount) > 0);
 156 }
 157
 158 /*
 159  * initialise the security for the init task
 160  */
 161 static void cred_init_security(void)
 162 {
 163         struct cred *cred = (struct cred *) current->real_cred;
 164         struct task_security_struct *tsec;
 165
 166         tsec = kzalloc(sizeof(struct task_security_struct), GFP_KERNEL);
 167         if (!tsec)
 168                 panic("SELinux:  Failed to initialize initial task.\n");
 169
 170         tsec->osid = tsec->sid = SECINITSID_KERNEL;
 171         cred->security = tsec;
 172 }
 173
 174 /*
 175  * get the security ID of a set of credentials
 176  */
 177 static inline u32 cred_sid(const struct cred *cred)
 178 {
 179         const struct task_security_struct *tsec;
 180
 181         tsec = cred->security;
 182         return tsec->sid;
 183 }
 184
 185 /*
 186  * get the objective security ID of a task
 187  */
 188 static inline u32 task_sid(const struct task_struct *task)
 189 {
 190         u32 sid;
 191
 192         rcu_read_lock();
 193         sid = cred_sid(__task_cred(task));
 194         rcu_read_unlock();
 195         return sid;
 196 }
 197
 198 /*
 199  * get the subjective security ID of the current task
 200  */
 201 static inline u32 current_sid(void)
 202 {
 203         const struct task_security_struct *tsec = current_cred()->security;
 204
 205         return tsec->sid;
 206 }
 207
 208 /* Allocate and free functions for each kind of security blob. */
 209
 210 static int inode_alloc_security(struct inode *inode)
 211 {
 212         struct inode_security_struct *isec;
 213         u32 sid = current_sid();
 214
 215         isec = kmem_cache_zalloc(sel_inode_cache, GFP_NOFS);
 216         if (!isec)
 217                 return -ENOMEM;
 218
 219         mutex_init(&isec->lock);
 220         INIT_LIST_HEAD(&isec->list);
 221         isec->inode = inode;
 222         isec->sid = SECINITSID_UNLABELED;
 223         isec->sclass = SECCLASS_FILE;
 224         isec->task_sid = sid;
 225         inode->i_security = isec;
 226
 227         return 0;
 228 }
 229
 230 static void inode_free_security(struct inode *inode)
 231 {
 232         struct inode_security_struct *isec = inode->i_security;
 233         struct superblock_security_struct *sbsec = inode->i_sb->s_security;
 234
 235         spin_lock(&sbsec->isec_lock);
 236         if (!list_empty(&isec->list))
 237                 list_del_init(&isec->list);
 238         spin_unlock(&sbsec->isec_lock);
 239
 240         inode->i_security = NULL;
 241         kmem_cache_free(sel_inode_cache, isec);
 242 }
 243
 244 static int file_alloc_security(struct file *file)
 245 {
 246         struct file_security_struct *fsec;
 247         u32 sid = current_sid();
 248
 249         fsec = kzalloc(sizeof(struct file_security_struct), GFP_KERNEL);
 250         if (!fsec)
 251                 return -ENOMEM;
 252
 253         fsec->sid = sid;
 254         fsec->fown_sid = sid;
 255         file->f_security = fsec;
 256
 257         return 0;
 258 }
 259
 260 static void file_free_security(struct file *file)
 261 {
 262         struct file_security_struct *fsec = file->f_security;
 263         file->f_security = NULL;
 264         kfree(fsec);
 265 }
 266
 267 static int superblock_alloc_security(struct super_block *sb)
 268 {
 269         struct superblock_security_struct *sbsec;
 270
 271         sbsec = kzalloc(sizeof(struct superblock_security_struct), GFP_KERNEL);
 272         if (!sbsec)
 273                 return -ENOMEM;
 274
 275         mutex_init(&sbsec->lock);
 276         INIT_LIST_HEAD(&sbsec->list);
 277         INIT_LIST_HEAD(&sbsec->isec_head);
 278         spin_lock_init(&sbsec->isec_lock);
 279         sbsec->sb = sb;
 280         sbsec->sid = SECINITSID_UNLABELED;
 281         sbsec->def_sid = SECINITSID_FILE;
 282         sbsec->mntpoint_sid = SECINITSID_UNLABELED;
 283         sb->s_security = sbsec;
 284
 285         return 0;
 286 }
 287
 288 static void superblock_free_security(struct super_block *sb)
 289 {
 290         struct superblock_security_struct *sbsec = sb->s_security;
 291
 292         spin_lock(&sb_security_lock);
 293         if (!list_empty(&sbsec->list))
 294                 list_del_init(&sbsec->list);
 295         spin_unlock(&sb_security_lock);
 296
 297         sb->s_security = NULL;
 298         kfree(sbsec);
 299 }
 300
 301 static int sk_alloc_security(struct sock *sk, int family, gfp_t priority)
 302 {
 303         struct sk_security_struct *ssec;
 304
 305         ssec = kzalloc(sizeof(*ssec), priority);
 306         if (!ssec)
 307                 return -ENOMEM;
 308
 309         ssec->peer_sid = SECINITSID_UNLABELED;
 310         ssec->sid = SECINITSID_UNLABELED;
 311         sk->sk_security = ssec;
 312
 313         selinux_netlbl_sk_security_reset(ssec);
 314
 315         return 0;
 316 }
 317
 318 static void sk_free_security(struct sock *sk)
 319 {
 320         struct sk_security_struct *ssec = sk->sk_security;
 321
 322         sk->sk_security = NULL;
 323         selinux_netlbl_sk_security_free(ssec);
 324         kfree(ssec);
 325 }
 326
 327 /* The security server must be initialized before
 328    any labeling or access decisions can be provided. */
 329 extern int ss_initialized;
 330
 331 /* The file system's label must be initialized prior to use. */
 332
 333 static char *labeling_behaviors[6] = {
 334         "uses xattr",
 335         "uses transition SIDs",
 336         "uses task SIDs",
 337         "uses genfs_contexts",
 338         "not configured for labeling",
 339         "uses mountpoint labeling",
 340 };
 341
 342 static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dentry);
 343
 344 static inline int inode_doinit(struct inode *inode)
 345 {
 346         return inode_doinit_with_dentry(inode, NULL);
 347 }
 348
 349 enum {
 350         Opt_error = -1,
 351         Opt_context = 1,
 352         Opt_fscontext = 2,
 353         Opt_defcontext = 3,
 354         Opt_rootcontext = 4,
 355         Opt_labelsupport = 5,
 356 };
 357
 358 static const match_table_t tokens = {
 359         {Opt_context, CONTEXT_STR "%s"},
 360         {Opt_fscontext, FSCONTEXT_STR "%s"},
 361         {Opt_defcontext, DEFCONTEXT_STR "%s"},
 362         {Opt_rootcontext, ROOTCONTEXT_STR "%s"},
 363         {Opt_labelsupport, LABELSUPP_STR},
 364         {Opt_error, NULL},
 365 };
 366
 367 #define SEL_MOUNT_FAIL_MSG "SELinux:  duplicate or incompatible mount options\n"
 368
 369 static int may_context_mount_sb_relabel(u32 sid,
 370                         struct superblock_security_struct *sbsec,
 371                         const struct cred *cred)
 372 {
 373         const struct task_security_struct *tsec = cred->security;
 374         int rc;
 375
 376         rc = avc_has_perm(tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM,
 377                           FILESYSTEM__RELABELFROM, NULL);
 378         if (rc)
 379                 return rc;
 380
 381         rc = avc_has_perm(tsec->sid, sid, SECCLASS_FILESYSTEM,
 382                           FILESYSTEM__RELABELTO, NULL);
 383         return rc;
 384 }
 385
 386 static int may_context_mount_inode_relabel(u32 sid,
 387                         struct superblock_security_struct *sbsec,
 388                         const struct cred *cred)
 389 {
 390         const struct task_security_struct *tsec = cred->security;
 391         int rc;
 392         rc = avc_has_perm(tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM,
 393                           FILESYSTEM__RELABELFROM, NULL);
 394         if (rc)
 395                 return rc;
 396
 397         rc = avc_has_perm(sid, sbsec->sid, SECCLASS_FILESYSTEM,
 398                           FILESYSTEM__ASSOCIATE, NULL);
 399         return rc;
 400 }
 401
 402 static int sb_finish_set_opts(struct super_block *sb)
 403 {
 404         struct superblock_security_struct *sbsec = sb->s_security;
 405         struct dentry *root = sb->s_root;
 406         struct inode *root_inode = root->d_inode;
 407         int rc = 0;
 408
 409         if (sbsec->behavior == SECURITY_FS_USE_XATTR) {
 410                 /* Make sure that the xattr handler exists and that no
 411                    error other than -ENODATA is returned by getxattr on
 412                    the root directory.  -ENODATA is ok, as this may be
 413                    the first boot of the SELinux kernel before we have
 414                    assigned xattr values to the filesystem. */
 415                 if (!root_inode->i_op->getxattr) {
 416                         printk(KERN_WARNING "SELinux: (dev %s, type %s) has no "
 417                                "xattr support\n", sb->s_id, sb->s_type->name);
 418                         rc = -EOPNOTSUPP;
 419                         goto out;
 420                 }
 421                 rc = root_inode->i_op->getxattr(root, XATTR_NAME_SELINUX, NULL, 0);
 422                 if (rc < 0 && rc != -ENODATA) {
 423                         if (rc == -EOPNOTSUPP)
 424                                 printk(KERN_WARNING "SELinux: (dev %s, type "
 425                                        "%s) has no security xattr handler\n",
 426                                        sb->s_id, sb->s_type->name);
 427                         else
 428                                 printk(KERN_WARNING "SELinux: (dev %s, type "
 429                                        "%s) getxattr errno %d\n", sb->s_id,
 430                                        sb->s_type->name, -rc);
 431                         goto out;
 432                 }
 433         }
 434
 435         sbsec->flags |= (SE_SBINITIALIZED | SE_SBLABELSUPP);
 436
 437         if (sbsec->behavior > ARRAY_SIZE(labeling_behaviors))
 438                 printk(KERN_ERR "SELinux: initialized (dev %s, type %s), unknown behavior\n",
 439                        sb->s_id, sb->s_type->name);
 440         else
 441                 printk(KERN_DEBUG "SELinux: initialized (dev %s, type %s), %s\n",
 442                        sb->s_id, sb->s_type->name,
 443                        labeling_behaviors[sbsec->behavior-1]);
 444
 445         if (sbsec->behavior == SECURITY_FS_USE_GENFS ||
 446             sbsec->behavior == SECURITY_FS_USE_MNTPOINT ||
 447             sbsec->behavior == SECURITY_FS_USE_NONE ||
 448             sbsec->behavior > ARRAY_SIZE(labeling_behaviors))
 449                 sbsec->flags &= ~SE_SBLABELSUPP;
 450
 451         /* Initialize the root inode. */
 452         rc = inode_doinit_with_dentry(root_inode, root);
 453
 454         /* Initialize any other inodes associated with the superblock, e.g.
 455            inodes created prior to initial policy load or inodes created
 456            during get_sb by a pseudo filesystem that directly
 457            populates itself. */
 458         spin_lock(&sbsec->isec_lock);
 459 next_inode:
 460         if (!list_empty(&sbsec->isec_head)) {
 461                 struct inode_security_struct *isec =
 462                                 list_entry(sbsec->isec_head.next,
 463                                            struct inode_security_struct, list);
 464                 struct inode *inode = isec->inode;
 465                 spin_unlock(&sbsec->isec_lock);
 466                 inode = igrab(inode);
 467                 if (inode) {
 468                         if (!IS_PRIVATE(inode))
 469                                 inode_doinit(inode);
 470                         iput(inode);
 471                 }
 472                 spin_lock(&sbsec->isec_lock);
 473                 list_del_init(&isec->list);
 474                 goto next_inode;
 475         }
 476         spin_unlock(&sbsec->isec_lock);
 477 out:
 478         return rc;
 479 }
 480
 481 /*
 482  * This function should allow an FS to ask what it's mount security
 483  * options were so it can use those later for submounts, displaying
 484  * mount options, or whatever.
 485  */
 486 static int selinux_get_mnt_opts(const struct super_block *sb,
 487                                 struct security_mnt_opts *opts)
 488 {
 489         int rc = 0, i;
 490         struct superblock_security_struct *sbsec = sb->s_security;
 491         char *context = NULL;
 492         u32 len;
 493         char tmp;
 494
 495         security_init_mnt_opts(opts);
 496
 497         if (!(sbsec->flags & SE_SBINITIALIZED))
 498                 return -EINVAL;
 499
 500         if (!ss_initialized)
 501                 return -EINVAL;
 502
 503         tmp = sbsec->flags & SE_MNTMASK;
 504         /* count the number of mount options for this sb */
 505         for (i = 0; i < 8; i++) {
 506                 if (tmp & 0x01)
 507                         opts->num_mnt_opts++;
 508                 tmp >>= 1;
 509         }
 510         /* Check if the Label support flag is set */
 511         if (sbsec->flags & SE_SBLABELSUPP)
 512                 opts->num_mnt_opts++;
 513
 514         opts->mnt_opts = kcalloc(opts->num_mnt_opts, sizeof(char *), GFP_ATOMIC);
 515         if (!opts->mnt_opts) {
 516                 rc = -ENOMEM;
 517                 goto out_free;
 518         }
 519
 520         opts->mnt_opts_flags = kcalloc(opts->num_mnt_opts, sizeof(int), GFP_ATOMIC);
 521         if (!opts->mnt_opts_flags) {
 522                 rc = -ENOMEM;
 523                 goto out_free;
 524         }
 525
 526         i = 0;
 527         if (sbsec->flags & FSCONTEXT_MNT) {
 528                 rc = security_sid_to_context(sbsec->sid, &context, &len);
 529                 if (rc)
 530                         goto out_free;
 531                 opts->mnt_opts[i] = context;
 532                 opts->mnt_opts_flags[i++] = FSCONTEXT_MNT;
 533         }
 534         if (sbsec->flags & CONTEXT_MNT) {
 535                 rc = security_sid_to_context(sbsec->mntpoint_sid, &context, &len);
 536                 if (rc)
 537                         goto out_free;
 538                 opts->mnt_opts[i] = context;
 539                 opts->mnt_opts_flags[i++] = CONTEXT_MNT;
 540         }
 541         if (sbsec->flags & DEFCONTEXT_MNT) {
 542                 rc = security_sid_to_context(sbsec->def_sid, &context, &len);
 543                 if (rc)
 544                         goto out_free;
 545                 opts->mnt_opts[i] = context;
 546                 opts->mnt_opts_flags[i++] = DEFCONTEXT_MNT;
 547         }
 548         if (sbsec->flags & ROOTCONTEXT_MNT) {
 549                 struct inode *root = sbsec->sb->s_root->d_inode;
 550                 struct inode_security_struct *isec = root->i_security;
 551
 552                 rc = security_sid_to_context(isec->sid, &context, &len);
 553                 if (rc)
 554                         goto out_free;
 555                 opts->mnt_opts[i] = context;
 556                 opts->mnt_opts_flags[i++] = ROOTCONTEXT_MNT;
 557         }
 558         if (sbsec->flags & SE_SBLABELSUPP) {
 559                 opts->mnt_opts[i] = NULL;
 560                 opts->mnt_opts_flags[i++] = SE_SBLABELSUPP;
 561         }
 562
 563         BUG_ON(i != opts->num_mnt_opts);
 564
 565         return 0;
 566
 567 out_free:
 568         security_free_mnt_opts(opts);
 569         return rc;
 570 }
 571
 572 static int bad_option(struct superblock_security_struct *sbsec, char flag,
 573                       u32 old_sid, u32 new_sid)
 574 {
 575         char mnt_flags = sbsec->flags & SE_MNTMASK;
 576
 577         /* check if the old mount command had the same options */
 578         if (sbsec->flags & SE_SBINITIALIZED)
 579                 if (!(sbsec->flags & flag) ||
 580                     (old_sid != new_sid))
 581                         return 1;
 582
 583         /* check if we were passed the same options twice,
 584          * aka someone passed context=a,context=b
 585          */
 586         if (!(sbsec->flags & SE_SBINITIALIZED))
 587                 if (mnt_flags & flag)
 588                         return 1;
 589         return 0;
 590 }
 591
 592 /*
 593  * Allow filesystems with binary mount data to explicitly set mount point
 594  * labeling information.
 595  */
 596 static int selinux_set_mnt_opts(struct super_block *sb,
 597                                 struct security_mnt_opts *opts)
 598 {
 599         const struct cred *cred = current_cred();
 600         int rc = 0, i;
 601         struct superblock_security_struct *sbsec = sb->s_security;
 602         const char *name = sb->s_type->name;
 603         struct inode *inode = sbsec->sb->s_root->d_inode;
 604         struct inode_security_struct *root_isec = inode->i_security;
 605         u32 fscontext_sid = 0, context_sid = 0, rootcontext_sid = 0;
 606         u32 defcontext_sid = 0;
 607         char **mount_options = opts->mnt_opts;
 608         int *flags = opts->mnt_opts_flags;
 609         int num_opts = opts->num_mnt_opts;
 610
 611         mutex_lock(&sbsec->lock);
 612
 613         if (!ss_initialized) {
 614                 if (!num_opts) {
 615                         /* Defer initialization until selinux_complete_init,
 616                            after the initial policy is loaded and the security
 617                            server is ready to handle calls. */
 618                         spin_lock(&sb_security_lock);
 619                         if (list_empty(&sbsec->list))
 620                                 list_add(&sbsec->list, &superblock_security_head);
 621                         spin_unlock(&sb_security_lock);
 622                         goto out;
 623                 }
 624                 rc = -EINVAL;
 625                 printk(KERN_WARNING "SELinux: Unable to set superblock options "
 626                         "before the security server is initialized\n");
 627                 goto out;
 628         }
 629
 630         /*
 631          * Binary mount data FS will come through this function twice.  Once
 632          * from an explicit call and once from the generic calls from the vfs.
 633          * Since the generic VFS calls will not contain any security mount data
 634          * we need to skip the double mount verification.
 635          *
 636          * This does open a hole in which we will not notice if the first
 637          * mount using this sb set explict options and a second mount using
 638          * this sb does not set any security options.  (The first options
 639          * will be used for both mounts)
 640          */
 641         if ((sbsec->flags & SE_SBINITIALIZED) && (sb->s_type->fs_flags & FS_BINARY_MOUNTDATA)
 642             && (num_opts == 0))
 643                 goto out;
 644
 645         /*
 646          * parse the mount options, check if they are valid sids.
 647          * also check if someone is trying to mount the same sb more
 648          * than once with different security options.
 649          */
 650         for (i = 0; i < num_opts; i++) {
 651                 u32 sid;
 652
 653                 if (flags[i] == SE_SBLABELSUPP)
 654                         continue;
 655                 rc = security_context_to_sid(mount_options[i],
 656                                              strlen(mount_options[i]), &sid);
 657                 if (rc) {
 658                         printk(KERN_WARNING "SELinux: security_context_to_sid"
 659                                "(%s) failed for (dev %s, type %s) errno=%d\n",
 660                                mount_options[i], sb->s_id, name, rc);
 661                         goto out;
 662                 }
 663                 switch (flags[i]) {
 664                 case FSCONTEXT_MNT:
 665                         fscontext_sid = sid;
 666
 667                         if (bad_option(sbsec, FSCONTEXT_MNT, sbsec->sid,
 668                                         fscontext_sid))
 669                                 goto out_double_mount;
 670
 671                         sbsec->flags |= FSCONTEXT_MNT;
 672                         break;
 673                 case CONTEXT_MNT:
 674                         context_sid = sid;
 675
 676                         if (bad_option(sbsec, CONTEXT_MNT, sbsec->mntpoint_sid,
 677                                         context_sid))
 678                                 goto out_double_mount;
 679
 680                         sbsec->flags |= CONTEXT_MNT;
 681                         break;
 682                 case ROOTCONTEXT_MNT:
 683                         rootcontext_sid = sid;
 684
 685                         if (bad_option(sbsec, ROOTCONTEXT_MNT, root_isec->sid,
 686                                         rootcontext_sid))
 687                                 goto out_double_mount;
 688
 689                         sbsec->flags |= ROOTCONTEXT_MNT;
 690
 691                         break;
 692                 case DEFCONTEXT_MNT:
 693                         defcontext_sid = sid;
 694
 695                         if (bad_option(sbsec, DEFCONTEXT_MNT, sbsec->def_sid,
 696                                         defcontext_sid))
 697                                 goto out_double_mount;
 698
 699                         sbsec->flags |= DEFCONTEXT_MNT;
 700
 701                         break;
 702                 default:
 703                         rc = -EINVAL;
 704                         goto out;
 705                 }
 706         }
 707
 708         if (sbsec->flags & SE_SBINITIALIZED) {
 709                 /* previously mounted with options, but not on this attempt? */
 710                 if ((sbsec->flags & SE_MNTMASK) && !num_opts)
 711                         goto out_double_mount;
 712                 rc = 0;
 713                 goto out;
 714         }
 715
 716         if (strcmp(sb->s_type->name, "proc") == 0)
 717                 sbsec->flags |= SE_SBPROC;
 718
 719         /* Determine the labeling behavior to use for this filesystem type. */
 720         rc = security_fs_use((sbsec->flags & SE_SBPROC) ? "proc" : sb->s_type->name, &sbsec->behavior, &sbsec->sid);
 721         if (rc) {
 722                 printk(KERN_WARNING "%s: security_fs_use(%s) returned %d\n",
 723                        __func__, sb->s_type->name, rc);
 724                 goto out;
 725         }
 726
 727         /* sets the context of the superblock for the fs being mounted. */
 728         if (fscontext_sid) {
 729                 rc = may_context_mount_sb_relabel(fscontext_sid, sbsec, cred);
 730                 if (rc)
 731                         goto out;
 732
 733                 sbsec->sid = fscontext_sid;
 734         }
 735
 736         /*
 737          * Switch to using mount point labeling behavior.
 738          * sets the label used on all file below the mountpoint, and will set
 739          * the superblock context if not already set.
 740          */
 741         if (context_sid) {
 742                 if (!fscontext_sid) {
 743                         rc = may_context_mount_sb_relabel(context_sid, sbsec,
 744                                                           cred);
 745                         if (rc)
 746                                 goto out;
 747                         sbsec->sid = context_sid;
 748                 } else {
 749                         rc = may_context_mount_inode_relabel(context_sid, sbsec,
 750                                                              cred);
 751                         if (rc)
 752                                 goto out;
 753                 }
 754                 if (!rootcontext_sid)
 755                         rootcontext_sid = context_sid;
 756
 757                 sbsec->mntpoint_sid = context_sid;
 758                 sbsec->behavior = SECURITY_FS_USE_MNTPOINT;
 759         }
 760
 761         if (rootcontext_sid) {
 762                 rc = may_context_mount_inode_relabel(rootcontext_sid, sbsec,
 763                                                      cred);
 764                 if (rc)
 765                         goto out;
 766
 767                 root_isec->sid = rootcontext_sid;
 768                 root_isec->initialized = 1;
 769         }
 770
 771         if (defcontext_sid) {
 772                 if (sbsec->behavior != SECURITY_FS_USE_XATTR) {
 773                         rc = -EINVAL;
 774                         printk(KERN_WARNING "SELinux: defcontext option is "
 775                                "invalid for this filesystem type\n");
 776                         goto out;
 777                 }
 778
 779                 if (defcontext_sid != sbsec->def_sid) {
 780                         rc = may_context_mount_inode_relabel(defcontext_sid,
 781                                                              sbsec, cred);
 782                         if (rc)
 783                                 goto out;
 784                 }
 785
 786                 sbsec->def_sid = defcontext_sid;
 787         }
 788
 789         rc = sb_finish_set_opts(sb);
 790 out:
 791         mutex_unlock(&sbsec->lock);
 792         return rc;
 793 out_double_mount:
 794         rc = -EINVAL;
 795         printk(KERN_WARNING "SELinux: mount invalid.  Same superblock, different "
 796                "security settings for (dev %s, type %s)\n", sb->s_id, name);
 797         goto out;
 798 }
 799
 800 static void selinux_sb_clone_mnt_opts(const struct super_block *oldsb,
 801                                         struct super_block *newsb)
 802 {
 803         const struct superblock_security_struct *oldsbsec = oldsb->s_security;
 804         struct superblock_security_struct *newsbsec = newsb->s_security;
 805
 806         int set_fscontext =     (oldsbsec->flags & FSCONTEXT_MNT);
 807         int set_context =       (oldsbsec->flags & CONTEXT_MNT);
 808         int set_rootcontext =   (oldsbsec->flags & ROOTCONTEXT_MNT);
 809
 810         /*
 811          * if the parent was able to be mounted it clearly had no special lsm
 812          * mount options.  thus we can safely put this sb on the list and deal
 813          * with it later
 814          */
 815         if (!ss_initialized) {
 816                 spin_lock(&sb_security_lock);
 817                 if (list_empty(&newsbsec->list))
 818                         list_add(&newsbsec->list, &superblock_security_head);
 819                 spin_unlock(&sb_security_lock);
 820                 return;
 821         }
 822
 823         /* how can we clone if the old one wasn't set up?? */
 824         BUG_ON(!(oldsbsec->flags & SE_SBINITIALIZED));
 825
 826         /* if fs is reusing a sb, just let its options stand... */
 827         if (newsbsec->flags & SE_SBINITIALIZED)
 828                 return;
 829
 830         mutex_lock(&newsbsec->lock);
 831
 832         newsbsec->flags = oldsbsec->flags;
 833
 834         newsbsec->sid = oldsbsec->sid;
 835         newsbsec->def_sid = oldsbsec->def_sid;
 836         newsbsec->behavior = oldsbsec->behavior;
 837
 838         if (set_context) {
 839                 u32 sid = oldsbsec->mntpoint_sid;
 840
 841                 if (!set_fscontext)
 842                         newsbsec->sid = sid;
 843                 if (!set_rootcontext) {
 844                         struct inode *newinode = newsb->s_root->d_inode;
 845                         struct inode_security_struct *newisec = newinode->i_security;
 846                         newisec->sid = sid;
 847                 }
 848                 newsbsec->mntpoint_sid = sid;
 849         }
 850         if (set_rootcontext) {
 851                 const struct inode *oldinode = oldsb->s_root->d_inode;
 852                 const struct inode_security_struct *oldisec = oldinode->i_security;
 853                 struct inode *newinode = newsb->s_root->d_inode;
 854                 struct inode_security_struct *newisec = newinode->i_security;
 855
 856                 newisec->sid = oldisec->sid;
 857         }
 858
 859         sb_finish_set_opts(newsb);
 860         mutex_unlock(&newsbsec->lock);
 861 }
 862
 863 static int selinux_parse_opts_str(char *options,
 864                                   struct security_mnt_opts *opts)
 865 {
 866         char *p;
 867         char *context = NULL, *defcontext = NULL;
 868         char *fscontext = NULL, *rootcontext = NULL;
 869         int rc, num_mnt_opts = 0;
 870
 871         opts->num_mnt_opts = 0;
 872
 873         /* Standard string-based options. */
 874         while ((p = strsep(&options, "|")) != NULL) {
 875                 int token;
 876                 substring_t args[MAX_OPT_ARGS];
 877
 878                 if (!*p)
 879                         continue;
 880
 881                 token = match_token(p, tokens, args);
 882
 883                 switch (token) {
 884                 case Opt_context:
 885                         if (context || defcontext) {
 886                                 rc = -EINVAL;
 887                                 printk(KERN_WARNING SEL_MOUNT_FAIL_MSG);
 888                                 goto out_err;
 889                         }
 890                         context = match_strdup(&args[0]);
 891                         if (!context) {
 892                                 rc = -ENOMEM;
 893                                 goto out_err;
 894                         }
 895                         break;
 896
 897                 case Opt_fscontext:
 898                         if (fscontext) {
 899                                 rc = -EINVAL;
 900                                 printk(KERN_WARNING SEL_MOUNT_FAIL_MSG);
 901                                 goto out_err;
 902                         }
 903                         fscontext = match_strdup(&args[0]);
 904                         if (!fscontext) {
 905                                 rc = -ENOMEM;
 906                                 goto out_err;
 907                         }
 908                         break;
 909
 910                 case Opt_rootcontext:
 911                         if (rootcontext) {
 912                                 rc = -EINVAL;
 913                                 printk(KERN_WARNING SEL_MOUNT_FAIL_MSG);
 914                                 goto out_err;
 915                         }
 916                         rootcontext = match_strdup(&args[0]);
 917                         if (!rootcontext) {
 918                                 rc = -ENOMEM;
 919                                 goto out_err;
 920                         }
 921                         break;
 922
 923                 case Opt_defcontext:
 924                         if (context || defcontext) {
 925                                 rc = -EINVAL;
 926                                 printk(KERN_WARNING SEL_MOUNT_FAIL_MSG);
 927                                 goto out_err;
 928                         }
 929                         defcontext = match_strdup(&args[0]);
 930                         if (!defcontext) {
 931                                 rc = -ENOMEM;
 932                                 goto out_err;
 933                         }
 934                         break;
 935                 case Opt_labelsupport:
 936                         break;
 937                 default:
 938                         rc = -EINVAL;
 939                         printk(KERN_WARNING "SELinux:  unknown mount option\n");
 940                         goto out_err;
 941
 942                 }
 943         }
 944
 945         rc = -ENOMEM;
 946         opts->mnt_opts = kcalloc(NUM_SEL_MNT_OPTS, sizeof(char *), GFP_ATOMIC);
 947         if (!opts->mnt_opts)
 948                 goto out_err;
 949
 950         opts->mnt_opts_flags = kcalloc(NUM_SEL_MNT_OPTS, sizeof(int), GFP_ATOMIC);
 951         if (!opts->mnt_opts_flags) {
 952                 kfree(opts->mnt_opts);
 953                 goto out_err;
 954         }
 955
 956         if (fscontext) {
 957                 opts->mnt_opts[num_mnt_opts] = fscontext;
 958                 opts->mnt_opts_flags[num_mnt_opts++] = FSCONTEXT_MNT;
 959         }
 960         if (context) {
 961                 opts->mnt_opts[num_mnt_opts] = context;
 962                 opts->mnt_opts_flags[num_mnt_opts++] = CONTEXT_MNT;
 963         }
 964         if (rootcontext) {
 965                 opts->mnt_opts[num_mnt_opts] = rootcontext;
 966                 opts->mnt_opts_flags[num_mnt_opts++] = ROOTCONTEXT_MNT;
 967         }
 968         if (defcontext) {
 969                 opts->mnt_opts[num_mnt_opts] = defcontext;
 970                 opts->mnt_opts_flags[num_mnt_opts++] = DEFCONTEXT_MNT;
 971         }
 972
 973         opts->num_mnt_opts = num_mnt_opts;
 974         return 0;
 975
 976 out_err:
 977         kfree(context);
 978         kfree(defcontext);
 979         kfree(fscontext);
 980         kfree(rootcontext);
 981         return rc;
 982 }
 983 /*
 984  * string mount options parsing and call set the sbsec
 985  */
 986 static int superblock_doinit(struct super_block *sb, void *data)
 987 {
 988         int rc = 0;
 989         char *options = data;
 990         struct security_mnt_opts opts;
 991
 992         security_init_mnt_opts(&opts);
 993
 994         if (!data)
 995                 goto out;
 996
 997         BUG_ON(sb->s_type->fs_flags & FS_BINARY_MOUNTDATA);
 998
 999         rc = selinux_parse_opts_str(options, &opts);
1000         if (rc)
1001                 goto out_err;
1002
1003 out:
1004         rc = selinux_set_mnt_opts(sb, &opts);
1005
1006 out_err:
1007         security_free_mnt_opts(&opts);
1008         return rc;
1009 }
1010
1011 static void selinux_write_opts(struct seq_file *m,
1012                                struct security_mnt_opts *opts)
1013 {
1014         int i;
1015         char *prefix;
1016
1017         for (i = 0; i < opts->num_mnt_opts; i++) {
1018                 char *has_comma;
1019
1020                 if (opts->mnt_opts[i])
1021                         has_comma = strchr(opts->mnt_opts[i], ',');
1022                 else
1023                         has_comma = NULL;
1024
1025                 switch (opts->mnt_opts_flags[i]) {
1026                 case CONTEXT_MNT:
1027                         prefix = CONTEXT_STR;
1028                         break;
1029                 case FSCONTEXT_MNT:
1030                         prefix = FSCONTEXT_STR;
1031                         break;
1032                 case ROOTCONTEXT_MNT:
1033                         prefix = ROOTCONTEXT_STR;
1034                         break;
1035                 case DEFCONTEXT_MNT:
1036                         prefix = DEFCONTEXT_STR;
1037                         break;
1038                 case SE_SBLABELSUPP:
1039                         seq_putc(m, ',');
1040                         seq_puts(m, LABELSUPP_STR);
1041                         continue;
1042                 default:
1043                         BUG();
1044                 };
1045                 /* we need a comma before each option */
1046                 seq_putc(m, ',');
1047                 seq_puts(m, prefix);
1048                 if (has_comma)
1049                         seq_putc(m, '\"');
1050                 seq_puts(m, opts->mnt_opts[i]);
1051                 if (has_comma)
1052                         seq_putc(m, '\"');
1053         }
1054 }
1055
1056 static int selinux_sb_show_options(struct seq_file *m, struct super_block *sb)
1057 {
1058         struct security_mnt_opts opts;
1059         int rc;
1060
1061         rc = selinux_get_mnt_opts(sb, &opts);
1062         if (rc) {
1063                 /* before policy load we may get EINVAL, don't show anything */
1064                 if (rc == -EINVAL)
1065                         rc = 0;
1066                 return rc;
1067         }
1068
1069         selinux_write_opts(m, &opts);
1070
1071         security_free_mnt_opts(&opts);
1072
1073         return rc;
1074 }
1075
1076 static inline u16 inode_mode_to_security_class(umode_t mode)
1077 {
1078         switch (mode & S_IFMT) {
1079         case S_IFSOCK:
1080                 return SECCLASS_SOCK_FILE;
1081         case S_IFLNK:
1082                 return SECCLASS_LNK_FILE;
1083         case S_IFREG:
1084                 return SECCLASS_FILE;
1085         case S_IFBLK:
1086                 return SECCLASS_BLK_FILE;
1087         case S_IFDIR:
1088                 return SECCLASS_DIR;
1089         case S_IFCHR:
1090                 return SECCLASS_CHR_FILE;
1091         case S_IFIFO:
1092                 return SECCLASS_FIFO_FILE;
1093
1094         }
1095
1096         return SECCLASS_FILE;
1097 }
1098
1099 static inline int default_protocol_stream(int protocol)
1100 {
1101         return (protocol == IPPROTO_IP || protocol == IPPROTO_TCP);
1102 }
1103
1104 static inline int default_protocol_dgram(int protocol)
1105 {
1106         return (protocol == IPPROTO_IP || protocol == IPPROTO_UDP);
1107 }
1108
1109 static inline u16 socket_type_to_security_class(int family, int type, int protocol)
1110 {
1111         switch (family) {
1112         case PF_UNIX:
1113                 switch (type) {
1114                 case SOCK_STREAM:
1115                 case SOCK_SEQPACKET:
1116                         return SECCLASS_UNIX_STREAM_SOCKET;
1117                 case SOCK_DGRAM:
1118                         return SECCLASS_UNIX_DGRAM_SOCKET;
1119                 }
1120                 break;
1121         case PF_INET:
1122         case PF_INET6:
1123                 switch (type) {
1124                 case SOCK_STREAM:
1125                         if (default_protocol_stream(protocol))
1126                                 return SECCLASS_TCP_SOCKET;
1127                         else
1128                                 return SECCLASS_RAWIP_SOCKET;
1129                 case SOCK_DGRAM:
1130                         if (default_protocol_dgram(protocol))
1131                                 return SECCLASS_UDP_SOCKET;
1132                         else
1133                                 return SECCLASS_RAWIP_SOCKET;
1134                 case SOCK_DCCP:
1135                         return SECCLASS_DCCP_SOCKET;
1136                 default:
1137                         return SECCLASS_RAWIP_SOCKET;
1138                 }
1139                 break;
1140         case PF_NETLINK:
1141                 switch (protocol) {
1142                 case NETLINK_ROUTE:
1143                         return SECCLASS_NETLINK_ROUTE_SOCKET;
1144                 case NETLINK_FIREWALL:
1145                         return SECCLASS_NETLINK_FIREWALL_SOCKET;
1146                 case NETLINK_INET_DIAG:
1147                         return SECCLASS_NETLINK_TCPDIAG_SOCKET;
1148                 case NETLINK_NFLOG:
1149                         return SECCLASS_NETLINK_NFLOG_SOCKET;
1150                 case NETLINK_XFRM:
1151                         return SECCLASS_NETLINK_XFRM_SOCKET;
1152                 case NETLINK_SELINUX:
1153                         return SECCLASS_NETLINK_SELINUX_SOCKET;
1154                 case NETLINK_AUDIT:
1155                         return SECCLASS_NETLINK_AUDIT_SOCKET;
1156                 case NETLINK_IP6_FW:
1157                         return SECCLASS_NETLINK_IP6FW_SOCKET;
1158                 case NETLINK_DNRTMSG:
1159                         return SECCLASS_NETLINK_DNRT_SOCKET;
1160                 case NETLINK_KOBJECT_UEVENT:
1161                         return SECCLASS_NETLINK_KOBJECT_UEVENT_SOCKET;
1162                 default:
1163                         return SECCLASS_NETLINK_SOCKET;
1164                 }
1165         case PF_PACKET:
1166                 return SECCLASS_PACKET_SOCKET;
1167         case PF_KEY:
1168                 return SECCLASS_KEY_SOCKET;
1169         case PF_APPLETALK:
1170                 return SECCLASS_APPLETALK_SOCKET;
1171         }
1172
1173         return SECCLASS_SOCKET;
1174 }
1175
1176 #ifdef CONFIG_PROC_FS
1177 static int selinux_proc_get_sid(struct proc_dir_entry *de,
1178                                 u16 tclass,
1179                                 u32 *sid)
1180 {
1181         int buflen, rc;
1182         char *buffer, *path, *end;
1183
1184         buffer = (char *)__get_free_page(GFP_KERNEL);
1185         if (!buffer)
1186                 return -ENOMEM;
1187
1188         buflen = PAGE_SIZE;
1189         end = buffer+buflen;
1190         *--end = '\0';
1191         buflen--;
1192         path = end-1;
1193         *path = '/';
1194         while (de && de != de->parent) {
1195                 buflen -= de->namelen + 1;
1196                 if (buflen < 0)
1197                         break;
1198                 end -= de->namelen;
1199                 memcpy(end, de->name, de->namelen);
1200                 *--end = '/';
1201                 path = end;
1202                 de = de->parent;
1203         }
1204         rc = security_genfs_sid("proc", path, tclass, sid);
1205         free_page((unsigned long)buffer);
1206         return rc;
1207 }
1208 #else
1209 static int selinux_proc_get_sid(struct proc_dir_entry *de,
1210                                 u16 tclass,
1211                                 u32 *sid)
1212 {
1213         return -EINVAL;
1214 }
1215 #endif
1216
1217 /* The inode's security attributes must be initialized before first use. */
1218 static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dentry)
1219 {
1220         struct superblock_security_struct *sbsec = NULL;
1221         struct inode_security_struct *isec = inode->i_security;
1222         u32 sid;
1223         struct dentry *dentry;
1224 #define INITCONTEXTLEN 255
1225         char *context = NULL;
1226         unsigned len = 0;
1227         int rc = 0;
1228
1229         if (isec->initialized)
1230                 goto out;
1231
1232         mutex_lock(&isec->lock);
1233         if (isec->initialized)
1234                 goto out_unlock;
1235
1236         sbsec = inode->i_sb->s_security;
1237         if (!(sbsec->flags & SE_SBINITIALIZED)) {
1238                 /* Defer initialization until selinux_complete_init,
1239                    after the initial policy is loaded and the security
1240                    server is ready to handle calls. */
1241                 spin_lock(&sbsec->isec_lock);
1242                 if (list_empty(&isec->list))
1243                         list_add(&isec->list, &sbsec->isec_head);
1244                 spin_unlock(&sbsec->isec_lock);
1245                 goto out_unlock;
1246         }
1247
1248         switch (sbsec->behavior) {
1249         case SECURITY_FS_USE_XATTR:
1250                 if (!inode->i_op->getxattr) {
1251                         isec->sid = sbsec->def_sid;
1252                         break;
1253                 }
1254
1255                 /* Need a dentry, since the xattr API requires one.
1256                    Life would be simpler if we could just pass the inode. */
1257                 if (opt_dentry) {
1258                         /* Called from d_instantiate or d_splice_alias. */
1259                         dentry = dget(opt_dentry);
1260                 } else {
1261                         /* Called from selinux_complete_init, try to find a dentry. */
1262                         dentry = d_find_alias(inode);
1263                 }
1264                 if (!dentry) {
1265                         /*
1266                          * this is can be hit on boot when a file is accessed
1267                          * before the policy is loaded.  When we load policy we
1268                          * may find inodes that have no dentry on the
1269                          * sbsec->isec_head list.  No reason to complain as these
1270                          * will get fixed up the next time we go through
1271                          * inode_doinit with a dentry, before these inodes could
1272                          * be used again by userspace.
1273                          */
1274                         goto out_unlock;
1275                 }
1276
1277                 len = INITCONTEXTLEN;
1278                 context = kmalloc(len+1, GFP_NOFS);
1279                 if (!context) {
1280                         rc = -ENOMEM;
1281                         dput(dentry);
1282                         goto out_unlock;
1283                 }
1284                 context[len] = '\0';
1285                 rc = inode->i_op->getxattr(dentry, XATTR_NAME_SELINUX,
1286                                            context, len);
1287                 if (rc == -ERANGE) {
1288                         /* Need a larger buffer.  Query for the right size. */
1289                         rc = inode->i_op->getxattr(dentry, XATTR_NAME_SELINUX,
1290                                                    NULL, 0);
1291                         if (rc < 0) {
1292                                 dput(dentry);
1293                                 goto out_unlock;
1294                         }
1295                         kfree(context);
1296                         len = rc;
1297                         context = kmalloc(len+1, GFP_NOFS);
1298                         if (!context) {
1299                                 rc = -ENOMEM;
1300                                 dput(dentry);
1301                                 goto out_unlock;
1302                         }
1303                         context[len] = '\0';
1304                         rc = inode->i_op->getxattr(dentry,
1305                                                    XATTR_NAME_SELINUX,
1306                                                    context, len);
1307                 }
1308                 dput(dentry);
1309                 if (rc < 0) {
1310                         if (rc != -ENODATA) {
1311                                 printk(KERN_WARNING "SELinux: %s:  getxattr returned "
1312                                        "%d for dev=%s ino=%ld\n", __func__,
1313                                        -rc, inode->i_sb->s_id, inode->i_ino);
1314                                 kfree(context);
1315                                 goto out_unlock;
1316                         }
1317                         /* Map ENODATA to the default file SID */
1318                         sid = sbsec->def_sid;
1319                         rc = 0;
1320                 } else {
1321                         rc = security_context_to_sid_default(context, rc, &sid,
1322                                                              sbsec->def_sid,
1323                                                              GFP_NOFS);
1324                         if (rc) {
1325                                 char *dev = inode->i_sb->s_id;
1326                                 unsigned long ino = inode->i_ino;
1327
1328                                 if (rc == -EINVAL) {
1329                                         if (printk_ratelimit())
1330                                                 printk(KERN_NOTICE "SELinux: inode=%lu on dev=%s was found to have an invalid "
1331                                                         "context=%s.  This indicates you may need to relabel the inode or the "
1332                                                         "filesystem in question.\n", ino, dev, context);
1333                                 } else {
1334                                         printk(KERN_WARNING "SELinux: %s:  context_to_sid(%s) "
1335                                                "returned %d for dev=%s ino=%ld\n",
1336                                                __func__, context, -rc, dev, ino);
1337                                 }
1338                                 kfree(context);
1339                                 /* Leave with the unlabeled SID */
1340                                 rc = 0;
1341                                 break;
1342                         }
1343                 }
1344                 kfree(context);
1345                 isec->sid = sid;
1346                 break;
1347         case SECURITY_FS_USE_TASK:
1348                 isec->sid = isec->task_sid;
1349                 break;
1350         case SECURITY_FS_USE_TRANS:
1351                 /* Default to the fs SID. */
1352                 isec->sid = sbsec->sid;
1353
1354                 /* Try to obtain a transition SID. */
1355                 isec->sclass = inode_mode_to_security_class(inode->i_mode);
1356                 rc = security_transition_sid(isec->task_sid,
1357                                              sbsec->sid,
1358                                              isec->sclass,
1359                                              &sid);
1360                 if (rc)
1361                         goto out_unlock;
1362                 isec->sid = sid;
1363                 break;
1364         case SECURITY_FS_USE_MNTPOINT:
1365                 isec->sid = sbsec->mntpoint_sid;
1366                 break;
1367         default:
1368                 /* Default to the fs superblock SID. */
1369                 isec->sid = sbsec->sid;
1370
1371                 if ((sbsec->flags & SE_SBPROC) && !S_ISLNK(inode->i_mode)) {
1372                         struct proc_inode *proci = PROC_I(inode);
1373                         if (proci->pde) {
1374                                 isec->sclass = inode_mode_to_security_class(inode->i_mode);
1375                                 rc = selinux_proc_get_sid(proci->pde,
1376                                                           isec->sclass,
1377                                                           &sid);
1378                                 if (rc)
1379                                         goto out_unlock;
1380                                 isec->sid = sid;
1381                         }
1382                 }
1383                 break;
1384         }
1385
1386         isec->initialized = 1;
1387
1388 out_unlock:
1389         mutex_unlock(&isec->lock);
1390 out:
1391         if (isec->sclass == SECCLASS_FILE)
1392                 isec->sclass = inode_mode_to_security_class(inode->i_mode);
1393         return rc;
1394 }
1395
1396 /* Convert a Linux signal to an access vector. */
1397 static inline u32 signal_to_av(int sig)
1398 {
1399         u32 perm = 0;
1400
1401         switch (sig) {
1402         case SIGCHLD:
1403                 /* Commonly granted from child to parent. */
1404                 perm = PROCESS__SIGCHLD;
1405                 break;
1406         case SIGKILL:
1407                 /* Cannot be caught or ignored */
1408                 perm = PROCESS__SIGKILL;
1409                 break;
1410         case SIGSTOP:
1411                 /* Cannot be caught or ignored */
1412                 perm = PROCESS__SIGSTOP;
1413                 break;
1414         default:
1415                 /* All other signals. */
1416                 perm = PROCESS__SIGNAL;
1417                 break;
1418         }
1419
1420         return perm;
1421 }
1422
1423 /*
1424  * Check permission between a pair of credentials
1425  * fork check, ptrace check, etc.
1426  */
1427 static int cred_has_perm(const struct cred *actor,
1428                          const struct cred *target,
1429                          u32 perms)
1430 {
1431         u32 asid = cred_sid(actor), tsid = cred_sid(target);
1432
1433         return avc_has_perm(asid, tsid, SECCLASS_PROCESS, perms, NULL);
1434 }
1435
1436 /*
1437  * Check permission between a pair of tasks, e.g. signal checks,
1438  * fork check, ptrace check, etc.
1439  * tsk1 is the actor and tsk2 is the target
1440  * - this uses the default subjective creds of tsk1
1441  */
1442 static int task_has_perm(const struct task_struct *tsk1,
1443                          const struct task_struct *tsk2,
1444                          u32 perms)
1445 {
1446         const struct task_security_struct *__tsec1, *__tsec2;
1447         u32 sid1, sid2;
1448
1449         rcu_read_lock();
1450         __tsec1 = __task_cred(tsk1)->security;  sid1 = __tsec1->sid;
1451         __tsec2 = __task_cred(tsk2)->security;  sid2 = __tsec2->sid;
1452         rcu_read_unlock();
1453         return avc_has_perm(sid1, sid2, SECCLASS_PROCESS, perms, NULL);
1454 }
1455
1456 /*
1457  * Check permission between current and another task, e.g. signal checks,
1458  * fork check, ptrace check, etc.
1459  * current is the actor and tsk2 is the target
1460  * - this uses current's subjective creds
1461  */
1462 static int current_has_perm(const struct task_struct *tsk,
1463                             u32 perms)
1464 {
1465         u32 sid, tsid;
1466
1467         sid = current_sid();
1468         tsid = task_sid(tsk);
1469         return avc_has_perm(sid, tsid, SECCLASS_PROCESS, perms, NULL);
1470 }
1471
1472 #if CAP_LAST_CAP > 63
1473 #error Fix SELinux to handle capabilities > 63.
1474 #endif
1475
1476 /* Check whether a task is allowed to use a capability. */
1477 static int task_has_capability(struct task_struct *tsk,
1478                                const struct cred *cred,
1479                                int cap, int audit)
1480 {
1481         struct avc_audit_data ad;
1482         struct av_decision avd;
1483         u16 sclass;
1484         u32 sid = cred_sid(cred);
1485         u32 av = CAP_TO_MASK(cap);
1486         int rc;
1487
1488         AVC_AUDIT_DATA_INIT(&ad, CAP);
1489         ad.tsk = tsk;
1490         ad.u.cap = cap;
1491
1492         switch (CAP_TO_INDEX(cap)) {
1493         case 0:
1494                 sclass = SECCLASS_CAPABILITY;
1495                 break;
1496         case 1:
1497                 sclass = SECCLASS_CAPABILITY2;
1498                 break;
1499         default:
1500                 printk(KERN_ERR
1501                        "SELinux:  out of range capability %d\n", cap);
1502                 BUG();
1503         }
1504
1505         rc = avc_has_perm_noaudit(sid, sid, sclass, av, 0, &avd);
1506         if (audit == SECURITY_CAP_AUDIT)
1507                 avc_audit(sid, sid, sclass, av, &avd, rc, &ad);
1508         return rc;
1509 }
1510
1511 /* Check whether a task is allowed to use a system operation. */
1512 static int task_has_system(struct task_struct *tsk,
1513                            u32 perms)
1514 {
1515         u32 sid = task_sid(tsk);
1516
1517         return avc_has_perm(sid, SECINITSID_KERNEL,
1518                             SECCLASS_SYSTEM, perms, NULL);
1519 }
1520
1521 /* Check whether a task has a particular permission to an inode.
1522    The 'adp' parameter is optional and allows other audit
1523    data to be passed (e.g. the dentry). */
1524 static int inode_has_perm(const struct cred *cred,
1525                           struct inode *inode,
1526                           u32 perms,
1527                           struct avc_audit_data *adp)
1528 {
1529         struct inode_security_struct *isec;
1530         struct avc_audit_data ad;
1531         u32 sid;
1532
1533         if (unlikely(IS_PRIVATE(inode)))
1534                 return 0;
1535
1536         sid = cred_sid(cred);
1537         isec = inode->i_security;
1538
1539         if (!adp) {
1540                 adp = &ad;
1541                 AVC_AUDIT_DATA_INIT(&ad, FS);
1542                 ad.u.fs.inode = inode;
1543         }
1544
1545         return avc_has_perm(sid, isec->sid, isec->sclass, perms, adp);
1546 }
1547
1548 /* Same as inode_has_perm, but pass explicit audit data containing
1549    the dentry to help the auditing code to more easily generate the
1550    pathname if needed. */
1551 static inline int dentry_has_perm(const struct cred *cred,
1552                                   struct vfsmount *mnt,
1553                                   struct dentry *dentry,
1554                                   u32 av)
1555 {
1556         struct inode *inode = dentry->d_inode;
1557         struct avc_audit_data ad;
1558
1559         AVC_AUDIT_DATA_INIT(&ad, FS);
1560         ad.u.fs.path.mnt = mnt;
1561         ad.u.fs.path.dentry = dentry;
1562         return inode_has_perm(cred, inode, av, &ad);
1563 }
1564
1565 /* Check whether a task can use an open file descriptor to
1566    access an inode in a given way.  Check access to the
1567    descriptor itself, and then use dentry_has_perm to
1568    check a particular permission to the file.
1569    Access to the descriptor is implicitly granted if it
1570    has the same SID as the process.  If av is zero, then
1571    access to the file is not checked, e.g. for cases
1572    where only the descriptor is affected like seek. */
1573 static int file_has_perm(const struct cred *cred,
1574                          struct file *file,
1575                          u32 av)
1576 {
1577         struct file_security_struct *fsec = file->f_security;
1578         struct inode *inode = file->f_path.dentry->d_inode;
1579         struct avc_audit_data ad;
1580         u32 sid = cred_sid(cred);
1581         int rc;
1582
1583         AVC_AUDIT_DATA_INIT(&ad, FS);
1584         ad.u.fs.path = file->f_path;
1585
1586         if (sid != fsec->sid) {
1587                 rc = avc_has_perm(sid, fsec->sid,
1588                                   SECCLASS_FD,
1589                                   FD__USE,
1590                                   &ad);
1591                 if (rc)
1592                         goto out;
1593         }
1594
1595         /* av is zero if only checking access to the descriptor. */
1596         rc = 0;
1597         if (av)
1598                 rc = inode_has_perm(cred, inode, av, &ad);
1599
1600 out:
1601         return rc;
1602 }
1603
1604 /* Check whether a task can create a file. */
1605 static int may_create(struct inode *dir,
1606                       struct dentry *dentry,
1607                       u16 tclass)
1608 {
1609         const struct cred *cred = current_cred();
1610         const struct task_security_struct *tsec = cred->security;
1611         struct inode_security_struct *dsec;
1612         struct superblock_security_struct *sbsec;
1613         u32 sid, newsid;
1614         struct avc_audit_data ad;
1615         int rc;
1616
1617         dsec = dir->i_security;
1618         sbsec = dir->i_sb->s_security;
1619
1620         sid = tsec->sid;
1621         newsid = tsec->create_sid;
1622
1623         AVC_AUDIT_DATA_INIT(&ad, FS);
1624         ad.u.fs.path.dentry = dentry;
1625
1626         rc = avc_has_perm(sid, dsec->sid, SECCLASS_DIR,
1627                           DIR__ADD_NAME | DIR__SEARCH,
1628                           &ad);
1629         if (rc)
1630                 return rc;
1631
1632         if (!newsid || !(sbsec->flags & SE_SBLABELSUPP)) {
1633                 rc = security_transition_sid(sid, dsec->sid, tclass, &newsid);
1634                 if (rc)
1635                         return rc;
1636         }
1637
1638         rc = avc_has_perm(sid, newsid, tclass, FILE__CREATE, &ad);
1639         if (rc)
1640                 return rc;
1641
1642         return avc_has_perm(newsid, sbsec->sid,
1643                             SECCLASS_FILESYSTEM,
1644                             FILESYSTEM__ASSOCIATE, &ad);
1645 }
1646
1647 /* Check whether a task can create a key. */
1648 static int may_create_key(u32 ksid,
1649                           struct task_struct *ctx)
1650 {
1651         u32 sid = task_sid(ctx);
1652
1653         return avc_has_perm(sid, ksid, SECCLASS_KEY, KEY__CREATE, NULL);
1654 }
1655
1656 #define MAY_LINK        0
1657 #define MAY_UNLINK      1
1658 #define MAY_RMDIR       2
1659
1660 /* Check whether a task can link, unlink, or rmdir a file/directory. */
1661 static int may_link(struct inode *dir,
1662                     struct dentry *dentry,
1663                     int kind)
1664
1665 {
1666         struct inode_security_struct *dsec, *isec;
1667         struct avc_audit_data ad;
1668         u32 sid = current_sid();
1669         u32 av;
1670         int rc;
1671
1672         dsec = dir->i_security;
1673         isec = dentry->d_inode->i_security;
1674
1675         AVC_AUDIT_DATA_INIT(&ad, FS);
1676         ad.u.fs.path.dentry = dentry;
1677
1678         av = DIR__SEARCH;
1679         av |= (kind ? DIR__REMOVE_NAME : DIR__ADD_NAME);
1680         rc = avc_has_perm(sid, dsec->sid, SECCLASS_DIR, av, &ad);
1681         if (rc)
1682                 return rc;
1683
1684         switch (kind) {
1685         case MAY_LINK:
1686                 av = FILE__LINK;
1687                 break;
1688         case MAY_UNLINK:
1689                 av = FILE__UNLINK;
1690                 break;
1691         case MAY_RMDIR:
1692                 av = DIR__RMDIR;
1693                 break;
1694         default:
1695                 printk(KERN_WARNING "SELinux: %s:  unrecognized kind %d\n",
1696                         __func__, kind);
1697                 return 0;
1698         }
1699
1700         rc = avc_has_perm(sid, isec->sid, isec->sclass, av, &ad);
1701         return rc;
1702 }
1703
1704 static inline int may_rename(struct inode *old_dir,
1705                              struct dentry *old_dentry,
1706                              struct inode *new_dir,
1707                              struct dentry *new_dentry)
1708 {
1709         struct inode_security_struct *old_dsec, *new_dsec, *old_isec, *new_isec;
1710         struct avc_audit_data ad;
1711         u32 sid = current_sid();
1712         u32 av;
1713         int old_is_dir, new_is_dir;
1714         int rc;
1715
1716         old_dsec = old_dir->i_security;
1717         old_isec = old_dentry->d_inode->i_security;
1718         old_is_dir = S_ISDIR(old_dentry->d_inode->i_mode);
1719         new_dsec = new_dir->i_security;
1720
1721         AVC_AUDIT_DATA_INIT(&ad, FS);
1722
1723         ad.u.fs.path.dentry = old_dentry;
1724         rc = avc_has_perm(sid, old_dsec->sid, SECCLASS_DIR,
1725                           DIR__REMOVE_NAME | DIR__SEARCH, &ad);
1726         if (rc)
1727                 return rc;
1728         rc = avc_has_perm(sid, old_isec->sid,
1729                           old_isec->sclass, FILE__RENAME, &ad);
1730         if (rc)
1731                 return rc;
1732         if (old_is_dir && new_dir != old_dir) {
1733                 rc = avc_has_perm(sid, old_isec->sid,
1734                                   old_isec->sclass, DIR__REPARENT, &ad);
1735                 if (rc)
1736                         return rc;
1737         }
1738
1739         ad.u.fs.path.dentry = new_dentry;
1740         av = DIR__ADD_NAME | DIR__SEARCH;
1741         if (new_dentry->d_inode)
1742                 av |= DIR__REMOVE_NAME;
1743         rc = avc_has_perm(sid, new_dsec->sid, SECCLASS_DIR, av, &ad);
1744         if (rc)
1745                 return rc;
1746         if (new_dentry->d_inode) {
1747                 new_isec = new_dentry->d_inode->i_security;
1748                 new_is_dir = S_ISDIR(new_dentry->d_inode->i_mode);
1749                 rc = avc_has_perm(sid, new_isec->sid,
1750                                   new_isec->sclass,
1751                                   (new_is_dir ? DIR__RMDIR : FILE__UNLINK), &ad);
1752                 if (rc)
1753                         return rc;
1754         }
1755
1756         return 0;
1757 }
1758
1759 /* Check whether a task can perform a filesystem operation. */
1760 static int superblock_has_perm(const struct cred *cred,
1761                                struct super_block *sb,
1762                                u32 perms,
1763                                struct avc_audit_data *ad)
1764 {
1765         struct superblock_security_struct *sbsec;
1766         u32 sid = cred_sid(cred);
1767
1768         sbsec = sb->s_security;
1769         return avc_has_perm(sid, sbsec->sid, SECCLASS_FILESYSTEM, perms, ad);
1770 }
1771
1772 /* Convert a Linux mode and permission mask to an access vector. */
1773 static inline u32 file_mask_to_av(int mode, int mask)
1774 {
1775         u32 av = 0;
1776
1777         if ((mode & S_IFMT) != S_IFDIR) {
1778                 if (mask & MAY_EXEC)
1779                         av |= FILE__EXECUTE;
1780                 if (mask & MAY_READ)
1781                         av |= FILE__READ;
1782
1783                 if (mask & MAY_APPEND)
1784                         av |= FILE__APPEND;
1785                 else if (mask & MAY_WRITE)
1786                         av |= FILE__WRITE;
1787
1788         } else {
1789                 if (mask & MAY_EXEC)
1790                         av |= DIR__SEARCH;
1791                 if (mask & MAY_WRITE)
1792                         av |= DIR__WRITE;
1793                 if (mask & MAY_READ)
1794                         av |= DIR__READ;
1795         }
1796
1797         return av;
1798 }
1799
1800 /* Convert a Linux file to an access vector. */
1801 static inline u32 file_to_av(struct file *file)
1802 {
1803         u32 av = 0;
1804
1805         if (file->f_mode & FMODE_READ)
1806                 av |= FILE__READ;
1807         if (file->f_mode & FMODE_WRITE) {
1808                 if (file->f_flags & O_APPEND)
1809                         av |= FILE__APPEND;
1810                 else
1811                         av |= FILE__WRITE;
1812         }
1813         if (!av) {
1814                 /*
1815                  * Special file opened with flags 3 for ioctl-only use.
1816                  */
1817                 av = FILE__IOCTL;
1818         }
1819
1820         return av;
1821 }
1822
1823 /*
1824  * Convert a file to an access vector and include the correct open
1825  * open permission.
1826  */
1827 static inline u32 open_file_to_av(struct file *file)
1828 {
1829         u32 av = file_to_av(file);
1830
1831         if (selinux_policycap_openperm) {
1832                 mode_t mode = file->f_path.dentry->d_inode->i_mode;
1833                 /*
1834                  * lnk files and socks do not really have an 'open'
1835                  */
1836                 if (S_ISREG(mode))
1837                         av |= FILE__OPEN;
1838                 else if (S_ISCHR(mode))
1839                         av |= CHR_FILE__OPEN;
1840                 else if (S_ISBLK(mode))
1841                         av |= BLK_FILE__OPEN;
1842                 else if (S_ISFIFO(mode))
1843                         av |= FIFO_FILE__OPEN;
1844                 else if (S_ISDIR(mode))
1845                         av |= DIR__OPEN;
1846                 else if (S_ISSOCK(mode))
1847                         av |= SOCK_FILE__OPEN;
1848                 else
1849                         printk(KERN_ERR "SELinux: WARNING: inside %s with "
1850                                 "unknown mode:%o\n", __func__, mode);
1851         }
1852         return av;
1853 }
1854
1855 /* Hook functions begin here. */
1856
1857 static int selinux_ptrace_may_access(struct task_struct *child,
1858                                      unsigned int mode)
1859 {
1860         int rc;
1861
1862         rc = cap_ptrace_may_access(child, mode);
1863         if (rc)
1864                 return rc;
1865
1866         if (mode == PTRACE_MODE_READ) {
1867                 u32 sid = current_sid();
1868                 u32 csid = task_sid(child);
1869                 return avc_has_perm(sid, csid, SECCLASS_FILE, FILE__READ, NULL);
1870         }
1871
1872         return current_has_perm(child, PROCESS__PTRACE);
1873 }
1874
1875 static int selinux_ptrace_traceme(struct task_struct *parent)
1876 {
1877         int rc;
1878
1879         rc = cap_ptrace_traceme(parent);
1880         if (rc)
1881                 return rc;
1882
1883         return task_has_perm(parent, current, PROCESS__PTRACE);
1884 }
1885
1886 static int selinux_capget(struct task_struct *target, kernel_cap_t *effective,
1887                           kernel_cap_t *inheritable, kernel_cap_t *permitted)
1888 {
1889         int error;
1890
1891         error = current_has_perm(target, PROCESS__GETCAP);
1892         if (error)
1893                 return error;
1894
1895         return cap_capget(target, effective, inheritable, permitted);
1896 }
1897
1898 static int selinux_capset(struct cred *new, const struct cred *old,
1899                           const kernel_cap_t *effective,
1900                           const kernel_cap_t *inheritable,
1901                           const kernel_cap_t *permitted)
1902 {
1903         int error;
1904
1905         error = cap_capset(new, old,
1906                                       effective, inheritable, permitted);
1907         if (error)
1908                 return error;
1909
1910         return cred_has_perm(old, new, PROCESS__SETCAP);
1911 }
1912
1913 /*
1914  * (This comment used to live with the selinux_task_setuid hook,
1915  * which was removed).
1916  *
1917  * Since setuid only affects the current process, and since the SELinux
1918  * controls are not based on the Linux identity attributes, SELinux does not
1919  * need to control this operation.  However, SELinux does control the use of
1920  * the CAP_SETUID and CAP_SETGID capabilities using the capable hook.
1921  */
1922
1923 static int selinux_capable(struct task_struct *tsk, const struct cred *cred,
1924                            int cap, int audit)
1925 {
1926         int rc;
1927
1928         rc = cap_capable(tsk, cred, cap, audit);
1929         if (rc)
1930                 return rc;
1931
1932         return task_has_capability(tsk, cred, cap, audit);
1933 }
1934
1935 static int selinux_sysctl_get_sid(ctl_table *table, u16 tclass, u32 *sid)
1936 {
1937         int buflen, rc;
1938         char *buffer, *path, *end;
1939
1940         rc = -ENOMEM;
1941         buffer = (char *)__get_free_page(GFP_KERNEL);
1942         if (!buffer)
1943                 goto out;
1944
1945         buflen = PAGE_SIZE;
1946         end = buffer+buflen;
1947         *--end = '\0';
1948         buflen--;
1949         path = end-1;
1950         *path = '/';
1951         while (table) {
1952                 const char *name = table->procname;
1953                 size_t namelen = strlen(name);
1954                 buflen -= namelen + 1;
1955                 if (buflen < 0)
1956                         goto out_free;
1957                 end -= namelen;
1958                 memcpy(end, name, namelen);
1959                 *--end = '/';
1960                 path = end;
1961                 table = table->parent;
1962         }
1963         buflen -= 4;
1964         if (buflen < 0)
1965                 goto out_free;
1966         end -= 4;
1967         memcpy(end, "/sys", 4);
1968         path = end;
1969         rc = security_genfs_sid("proc", path, tclass, sid);
1970 out_free:
1971         free_page((unsigned long)buffer);
1972 out:
1973         return rc;
1974 }
1975
1976 static int selinux_sysctl(ctl_table *table, int op)
1977 {
1978         int error = 0;
1979         u32 av;
1980         u32 tsid, sid;
1981         int rc;
1982
1983         rc = secondary_ops->sysctl(table, op);
1984         if (rc)
1985                 return rc;
1986
1987         sid = current_sid();
1988
1989         rc = selinux_sysctl_get_sid(table, (op == 0001) ?
1990                                     SECCLASS_DIR : SECCLASS_FILE, &tsid);
1991         if (rc) {
1992                 /* Default to the well-defined sysctl SID. */
1993                 tsid = SECINITSID_SYSCTL;
1994         }
1995
1996         /* The op values are "defined" in sysctl.c, thereby creating
1997          * a bad coupling between this module and sysctl.c */
1998         if (op == 001) {
1999                 error = avc_has_perm(sid, tsid,
2000                                      SECCLASS_DIR, DIR__SEARCH, NULL);
2001         } else {
2002                 av = 0;
2003                 if (op & 004)
2004                         av |= FILE__READ;
2005                 if (op & 002)
2006                         av |= FILE__WRITE;
2007                 if (av)
2008                         error = avc_has_perm(sid, tsid,
2009                                              SECCLASS_FILE, av, NULL);
2010         }
2011
2012         return error;
2013 }
2014
2015 static int selinux_quotactl(int cmds, int type, int id, struct super_block *sb)
2016 {
2017         const struct cred *cred = current_cred();
2018         int rc = 0;
2019
2020         if (!sb)
2021                 return 0;
2022
2023         switch (cmds) {
2024         case Q_SYNC:
2025         case Q_QUOTAON:
2026         case Q_QUOTAOFF:
2027         case Q_SETINFO:
2028         case Q_SETQUOTA:
2029                 rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAMOD, NULL);
2030                 break;
2031         case Q_GETFMT:
2032         case Q_GETINFO:
2033         case Q_GETQUOTA:
2034                 rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAGET, NULL);
2035                 break;
2036         default:
2037                 rc = 0;  /* let the kernel handle invalid cmds */
2038                 break;
2039         }
2040         return rc;
2041 }
2042
2043 static int selinux_quota_on(struct dentry *dentry)
2044 {
2045         const struct cred *cred = current_cred();
2046
2047         return dentry_has_perm(cred, NULL, dentry, FILE__QUOTAON);
2048 }
2049
2050 static int selinux_syslog(int type)
2051 {
2052         int rc;
2053
2054         rc = cap_syslog(type);
2055         if (rc)
2056                 return rc;
2057
2058         switch (type) {
2059         case 3:         /* Read last kernel messages */
2060         case 10:        /* Return size of the log buffer */
2061                 rc = task_has_system(current, SYSTEM__SYSLOG_READ);
2062                 break;
2063         case 6:         /* Disable logging to console */
2064         case 7:         /* Enable logging to console */
2065         case 8:         /* Set level of messages printed to console */
2066                 rc = task_has_system(current, SYSTEM__SYSLOG_CONSOLE);
2067                 break;
2068         case 0:         /* Close log */
2069         case 1:         /* Open log */
2070         case 2:         /* Read from log */
2071         case 4:         /* Read/clear last kernel messages */
2072         case 5:         /* Clear ring buffer */
2073         default:
2074                 rc = task_has_system(current, SYSTEM__SYSLOG_MOD);
2075                 break;
2076         }
2077         return rc;
2078 }
2079
2080 /*
2081  * Check that a process has enough memory to allocate a new virtual
2082  * mapping. 0 means there is enough memory for the allocation to
2083  * succeed and -ENOMEM implies there is not.
2084  *
2085  * Do not audit the selinux permission check, as this is applied to all
2086  * processes that allocate mappings.
2087  */
2088 static int selinux_vm_enough_memory(struct mm_struct *mm, long pages)
2089 {
2090         int rc, cap_sys_admin = 0;
2091
2092         rc = selinux_capable(current, current_cred(), CAP_SYS_ADMIN,
2093                              SECURITY_CAP_NOAUDIT);
2094         if (rc == 0)
2095                 cap_sys_admin = 1;
2096
2097         return __vm_enough_memory(mm, pages, cap_sys_admin);
2098 }
2099
2100 /* binprm security operations */
2101
2102 static int selinux_bprm_set_creds(struct linux_binprm *bprm)
2103 {
2104         const struct task_security_struct *old_tsec;
2105         struct task_security_struct *new_tsec;
2106         struct inode_security_struct *isec;
2107         struct avc_audit_data ad;
2108         struct inode *inode = bprm->file->f_path.dentry->d_inode;
2109         int rc;
2110
2111         rc = cap_bprm_set_creds(bprm);
2112         if (rc)
2113                 return rc;
2114
2115         /* SELinux context only depends on initial program or script and not
2116          * the script interpreter */
2117         if (bprm->cred_prepared)
2118                 return 0;
2119
2120         old_tsec = current_security();
2121         new_tsec = bprm->cred->security;
2122         isec = inode->i_security;
2123
2124         /* Default to the current task SID. */
2125         new_tsec->sid = old_tsec->sid;
2126         new_tsec->osid = old_tsec->sid;
2127
2128         /* Reset fs, key, and sock SIDs on execve. */
2129         new_tsec->create_sid = 0;
2130         new_tsec->keycreate_sid = 0;
2131         new_tsec->sockcreate_sid = 0;
2132
2133         if (old_tsec->exec_sid) {
2134                 new_tsec->sid = old_tsec->exec_sid;
2135                 /* Reset exec SID on execve. */
2136                 new_tsec->exec_sid = 0;
2137         } else {
2138                 /* Check for a default transition on this program. */
2139                 rc = security_transition_sid(old_tsec->sid, isec->sid,
2140                                              SECCLASS_PROCESS, &new_tsec->sid);
2141                 if (rc)
2142                         return rc;
2143         }
2144
2145         AVC_AUDIT_DATA_INIT(&ad, FS);
2146         ad.u.fs.path = bprm->file->f_path;
2147
2148         if (bprm->file->f_path.mnt->mnt_flags & MNT_NOSUID)
2149                 new_tsec->sid = old_tsec->sid;
2150
2151         if (new_tsec->sid == old_tsec->sid) {
2152                 rc = avc_has_perm(old_tsec->sid, isec->sid,
2153                                   SECCLASS_FILE, FILE__EXECUTE_NO_TRANS, &ad);
2154                 if (rc)
2155                         return rc;
2156         } else {
2157                 /* Check permissions for the transition. */
2158                 rc = avc_has_perm(old_tsec->sid, new_tsec->sid,
2159                                   SECCLASS_PROCESS, PROCESS__TRANSITION, &ad);
2160                 if (rc)
2161                         return rc;
2162
2163                 rc = avc_has_perm(new_tsec->sid, isec->sid,
2164                                   SECCLASS_FILE, FILE__ENTRYPOINT, &ad);
2165                 if (rc)
2166                         return rc;
2167
2168                 /* Check for shared state */
2169                 if (bprm->unsafe & LSM_UNSAFE_SHARE) {
2170                         rc = avc_has_perm(old_tsec->sid, new_tsec->sid,
2171                                           SECCLASS_PROCESS, PROCESS__SHARE,
2172                                           NULL);
2173                         if (rc)
2174                                 return -EPERM;
2175                 }
2176
2177                 /* Make sure that anyone attempting to ptrace over a task that
2178                  * changes its SID has the appropriate permit */
2179                 if (bprm->unsafe &
2180                     (LSM_UNSAFE_PTRACE | LSM_UNSAFE_PTRACE_CAP)) {
2181                         struct task_struct *tracer;
2182                         struct task_security_struct *sec;
2183                         u32 ptsid = 0;
2184
2185                         rcu_read_lock();
2186                         tracer = tracehook_tracer_task(current);
2187                         if (likely(tracer != NULL)) {
2188                                 sec = __task_cred(tracer)->security;
2189                                 ptsid = sec->sid;
2190                         }
2191                         rcu_read_unlock();
2192
2193                         if (ptsid != 0) {
2194                                 rc = avc_has_perm(ptsid, new_tsec->sid,
2195                                                   SECCLASS_PROCESS,
2196                                                   PROCESS__PTRACE, NULL);
2197                                 if (rc)
2198                                         return -EPERM;
2199                         }
2200                 }
2201
2202                 /* Clear any possibly unsafe personality bits on exec: */
2203                 bprm->per_clear |= PER_CLEAR_ON_SETID;
2204         }
2205
2206         return 0;
2207 }
2208
2209 static int selinux_bprm_secureexec(struct linux_binprm *bprm)
2210 {
2211         const struct cred *cred = current_cred();
2212         const struct task_security_struct *tsec = cred->security;
2213         u32 sid, osid;
2214         int atsecure = 0;
2215
2216         sid = tsec->sid;
2217         osid = tsec->osid;
2218
2219         if (osid != sid) {
2220                 /* Enable secure mode for SIDs transitions unless
2221                    the noatsecure permission is granted between
2222                    the two SIDs, i.e. ahp returns 0. */
2223                 atsecure = avc_has_perm(osid, sid,
2224                                         SECCLASS_PROCESS,
2225                                         PROCESS__NOATSECURE, NULL);
2226         }
2227
2228         return (atsecure || cap_bprm_secureexec(bprm));
2229 }
2230
2231 extern struct vfsmount *selinuxfs_mount;
2232 extern struct dentry *selinux_null;
2233
2234 /* Derived from fs/exec.c:flush_old_files. */
2235 static inline void flush_unauthorized_files(const struct cred *cred,
2236                                             struct files_struct *files)
2237 {
2238         struct avc_audit_data ad;
2239         struct file *file, *devnull = NULL;
2240         struct tty_struct *tty;
2241         struct fdtable *fdt;
2242         long j = -1;
2243         int drop_tty = 0;
2244
2245         tty = get_current_tty();
2246         if (tty) {
2247                 file_list_lock();
2248                 if (!list_empty(&tty->tty_files)) {
2249                         struct inode *inode;
2250
2251                         /* Revalidate access to controlling tty.
2252                            Use inode_has_perm on the tty inode directly rather
2253                            than using file_has_perm, as this particular open
2254                            file may belong to another process and we are only
2255                            interested in the inode-based check here. */
2256                         file = list_first_entry(&tty->tty_files, struct file, f_u.fu_list);
2257                         inode = file->f_path.dentry->d_inode;
2258                         if (inode_has_perm(cred, inode,
2259                                            FILE__READ | FILE__WRITE, NULL)) {
2260                                 drop_tty = 1;
2261                         }
2262                 }
2263                 file_list_unlock();
2264                 tty_kref_put(tty);
2265         }
2266         /* Reset controlling tty. */
2267         if (drop_tty)
2268                 no_tty();
2269
2270         /* Revalidate access to inherited open files. */
2271
2272         AVC_AUDIT_DATA_INIT(&ad, FS);
2273
2274         spin_lock(&files->file_lock);
2275         for (;;) {
2276                 unsigned long set, i;
2277                 int fd;
2278
2279                 j++;
2280                 i = j * __NFDBITS;
2281                 fdt = files_fdtable(files);
2282                 if (i >= fdt->max_fds)
2283                         break;
2284                 set = fdt->open_fds->fds_bits[j];
2285                 if (!set)
2286                         continue;
2287                 spin_unlock(&files->file_lock);
2288                 for ( ; set ; i++, set >>= 1) {
2289                         if (set & 1) {
2290                                 file = fget(i);
2291                                 if (!file)
2292                                         continue;
2293                                 if (file_has_perm(cred,
2294                                                   file,
2295                                                   file_to_av(file))) {
2296                                         sys_close(i);
2297                                         fd = get_unused_fd();
2298                                         if (fd != i) {
2299                                                 if (fd >= 0)
2300                                                         put_unused_fd(fd);
2301                                                 fput(file);
2302                                                 continue;
2303                                         }
2304                                         if (devnull) {
2305                                                 get_file(devnull);
2306                                         } else {
2307                                                 devnull = dentry_open(
2308                                                         dget(selinux_null),
2309                                                         mntget(selinuxfs_mount),
2310                                                         O_RDWR, cred);
2311                                                 if (IS_ERR(devnull)) {
2312                                                         devnull = NULL;
2313                                                         put_unused_fd(fd);
2314                                                         fput(file);
2315                                                         continue;
2316                                                 }
2317                                         }
2318                                         fd_install(fd, devnull);
2319                                 }
2320                                 fput(file);
2321                         }
2322                 }
2323                 spin_lock(&files->file_lock);
2324
2325         }
2326         spin_unlock(&files->file_lock);
2327 }
2328
2329 /*
2330  * Prepare a process for imminent new credential changes due to exec
2331  */
2332 static void selinux_bprm_committing_creds(struct linux_binprm *bprm)
2333 {
2334         struct task_security_struct *new_tsec;
2335         struct rlimit *rlim, *initrlim;
2336         int rc, i;
2337
2338         new_tsec = bprm->cred->security;
2339         if (new_tsec->sid == new_tsec->osid)
2340                 return;
2341
2342         /* Close files for which the new task SID is not authorized. */
2343         flush_unauthorized_files(bprm->cred, current->files);
2344
2345         /* Always clear parent death signal on SID transitions. */
2346         current->pdeath_signal = 0;
2347
2348         /* Check whether the new SID can inherit resource limits from the old
2349          * SID.  If not, reset all soft limits to the lower of the current
2350          * task's hard limit and the init task's soft limit.
2351          *
2352          * Note that the setting of hard limits (even to lower them) can be
2353          * controlled by the setrlimit check.  The inclusion of the init task's
2354          * soft limit into the computation is to avoid resetting soft limits
2355          * higher than the default soft limit for cases where the default is
2356          * lower than the hard limit, e.g. RLIMIT_CORE or RLIMIT_STACK.
2357          */
2358         rc = avc_has_perm(new_tsec->osid, new_tsec->sid, SECCLASS_PROCESS,
2359                           PROCESS__RLIMITINH, NULL);
2360         if (rc) {
2361                 for (i = 0; i < RLIM_NLIMITS; i++) {
2362                         rlim = current->signal->rlim + i;
2363                         initrlim = init_task.signal->rlim + i;
2364                         rlim->rlim_cur = min(rlim->rlim_max, initrlim->rlim_cur);
2365                 }
2366                 update_rlimit_cpu(rlim->rlim_cur);
2367         }
2368 }
2369
2370 /*
2371  * Clean up the process immediately after the installation of new credentials
2372  * due to exec
2373  */
2374 static void selinux_bprm_committed_creds(struct linux_binprm *bprm)
2375 {
2376         const struct task_security_struct *tsec = current_security();
2377         struct itimerval itimer;
2378         struct sighand_struct *psig;
2379         u32 osid, sid;
2380         int rc, i;
2381         unsigned long flags;
2382
2383         osid = tsec->osid;
2384         sid = tsec->sid;
2385
2386         if (sid == osid)
2387                 return;
2388
2389         /* Check whether the new SID can inherit signal state from the old SID.
2390          * If not, clear itimers to avoid subsequent signal generation and
2391          * flush and unblock signals.
2392          *
2393          * This must occur _after_ the task SID has been updated so that any
2394          * kill done after the flush will be checked against the new SID.
2395          */
2396         rc = avc_has_perm(osid, sid, SECCLASS_PROCESS, PROCESS__SIGINH, NULL);
2397         if (rc) {
2398                 memset(&itimer, 0, sizeof itimer);
2399                 for (i = 0; i < 3; i++)
2400                         do_setitimer(i, &itimer, NULL);
2401                 flush_signals(current);
2402                 spin_lock_irq(&current->sighand->siglock);
2403                 flush_signal_handlers(current, 1);
2404                 sigemptyset(&current->blocked);
2405                 recalc_sigpending();
2406                 spin_unlock_irq(&current->sighand->siglock);
2407         }
2408
2409         /* Wake up the parent if it is waiting so that it can recheck
2410          * wait permission to the new task SID. */
2411         read_lock_irq(&tasklist_lock);
2412         psig = current->parent->sighand;
2413         spin_lock_irqsave(&psig->siglock, flags);
2414         wake_up_interruptible(&current->parent->signal->wait_chldexit);
2415         spin_unlock_irqrestore(&psig->siglock, flags);
2416         read_unlock_irq(&tasklist_lock);
2417 }
2418
2419 /* superblock security operations */
2420
2421 static int selinux_sb_alloc_security(struct super_block *sb)
2422 {
2423         return superblock_alloc_security(sb);
2424 }
2425
2426 static void selinux_sb_free_security(struct super_block *sb)
2427 {
2428         superblock_free_security(sb);
2429 }
2430
2431 static inline int match_prefix(char *prefix, int plen, char *option, int olen)
2432 {
2433         if (plen > olen)
2434                 return 0;
2435
2436         return !memcmp(prefix, option, plen);
2437 }
2438
2439 static inline int selinux_option(char *option, int len)
2440 {
2441         return (match_prefix(CONTEXT_STR, sizeof(CONTEXT_STR)-1, option, len) ||
2442                 match_prefix(FSCONTEXT_STR, sizeof(FSCONTEXT_STR)-1, option, len) ||
2443                 match_prefix(DEFCONTEXT_STR, sizeof(DEFCONTEXT_STR)-1, option, len) ||
2444                 match_prefix(ROOTCONTEXT_STR, sizeof(ROOTCONTEXT_STR)-1, option, len) ||
2445                 match_prefix(LABELSUPP_STR, sizeof(LABELSUPP_STR)-1, option, len));
2446 }
2447
2448 static inline void take_option(char **to, char *from, int *first, int len)
2449 {
2450         if (!*first) {
2451                 **to = ',';
2452                 *to += 1;
2453         } else
2454                 *first = 0;
2455         memcpy(*to, from, len);
2456         *to += len;
2457 }
2458
2459 static inline void take_selinux_option(char **to, char *from, int *first,
2460                                        int len)
2461 {
2462         int current_size = 0;
2463
2464         if (!*first) {
2465                 **to = '|';
2466                 *to += 1;
2467         } else
2468                 *first = 0;
2469
2470         while (current_size < len) {
2471                 if (*from != '"') {
2472                         **to = *from;
2473                         *to += 1;
2474                 }
2475                 from += 1;
2476                 current_size += 1;
2477         }
2478 }
2479
2480 static int selinux_sb_copy_data(char *orig, char *copy)
2481 {
2482         int fnosec, fsec, rc = 0;
2483         char *in_save, *in_curr, *in_end;
2484         char *sec_curr, *nosec_save, *nosec;
2485         int open_quote = 0;
2486
2487         in_curr = orig;
2488         sec_curr = copy;
2489
2490         nosec = (char *)get_zeroed_page(GFP_KERNEL);
2491         if (!nosec) {
2492                 rc = -ENOMEM;
2493                 goto out;
2494         }
2495
2496         nosec_save = nosec;
2497         fnosec = fsec = 1;
2498         in_save = in_end = orig;
2499
2500         do {
2501                 if (*in_end == '"')
2502                         open_quote = !open_quote;
2503                 if ((*in_end == ',' && open_quote == 0) ||
2504                                 *in_end == '\0') {
2505                         int len = in_end - in_curr;
2506
2507                         if (selinux_option(in_curr, len))
2508                                 take_selinux_option(&sec_curr, in_curr, &fsec, len);
2509                         else
2510                                 take_option(&nosec, in_curr, &fnosec, len);
2511
2512                         in_curr = in_end + 1;
2513                 }
2514         } while (*in_end++);
2515
2516         strcpy(in_save, nosec_save);
2517         free_page((unsigned long)nosec_save);
2518 out:
2519         return rc;
2520 }
2521
2522 static int selinux_sb_kern_mount(struct super_block *sb, int flags, void *data)
2523 {
2524         const struct cred *cred = current_cred();
2525         struct avc_audit_data ad;
2526         int rc;
2527
2528         rc = superblock_doinit(sb, data);
2529         if (rc)
2530                 return rc;
2531
2532         /* Allow all mounts performed by the kernel */
2533         if (flags & MS_KERNMOUNT)
2534                 return 0;
2535
2536         AVC_AUDIT_DATA_INIT(&ad, FS);
2537         ad.u.fs.path.dentry = sb->s_root;
2538         return superblock_has_perm(cred, sb, FILESYSTEM__MOUNT, &ad);
2539 }
2540
2541 static int selinux_sb_statfs(struct dentry *dentry)
2542 {
2543         const struct cred *cred = current_cred();
2544         struct avc_audit_data ad;
2545
2546         AVC_AUDIT_DATA_INIT(&ad, FS);
2547         ad.u.fs.path.dentry = dentry->d_sb->s_root;
2548         return superblock_has_perm(cred, dentry->d_sb, FILESYSTEM__GETATTR, &ad);
2549 }
2550
2551 static int selinux_mount(char *dev_name,
2552                          struct path *path,
2553                          char *type,
2554                          unsigned long flags,
2555                          void *data)
2556 {
2557         const struct cred *cred = current_cred();
2558
2559         if (flags & MS_REMOUNT)
2560                 return superblock_has_perm(cred, path->mnt->mnt_sb,
2561                                            FILESYSTEM__REMOUNT, NULL);
2562         else
2563                 return dentry_has_perm(cred, path->mnt, path->dentry,
2564                                        FILE__MOUNTON);
2565 }
2566
2567 static int selinux_umount(struct vfsmount *mnt, int flags)
2568 {
2569         const struct cred *cred = current_cred();
2570
2571         return superblock_has_perm(cred, mnt->mnt_sb,
2572                                    FILESYSTEM__UNMOUNT, NULL);
2573 }
2574
2575 /* inode security operations */
2576
2577 static int selinux_inode_alloc_security(struct inode *inode)
2578 {
2579         return inode_alloc_security(inode);
2580 }
2581
2582 static void selinux_inode_free_security(struct inode *inode)
2583 {
2584         inode_free_security(inode);
2585 }
2586
2587 static int selinux_inode_init_security(struct inode *inode, struct inode *dir,
2588                                        char **name, void **value,
2589                                        size_t *len)
2590 {
2591         const struct cred *cred = current_cred();
2592         const struct task_security_struct *tsec = cred->security;
2593         struct inode_security_struct *dsec;
2594         struct superblock_security_struct *sbsec;
2595         u32 sid, newsid, clen;
2596         int rc;
2597         char *namep = NULL, *context;
2598
2599         dsec = dir->i_security;
2600         sbsec = dir->i_sb->s_security;
2601
2602         sid = tsec->sid;
2603         newsid = tsec->create_sid;
2604
2605         if (!newsid || !(sbsec->flags & SE_SBLABELSUPP)) {
2606                 rc = security_transition_sid(sid, dsec->sid,
2607                                              inode_mode_to_security_class(inode->i_mode),
2608                                              &newsid);
2609                 if (rc) {
2610                         printk(KERN_WARNING "%s:  "
2611                                "security_transition_sid failed, rc=%d (dev=%s "
2612                                "ino=%ld)\n",
2613                                __func__,
2614                                -rc, inode->i_sb->s_id, inode->i_ino);
2615                         return rc;
2616                 }
2617         }
2618
2619         /* Possibly defer initialization to selinux_complete_init. */
2620         if (sbsec->flags & SE_SBINITIALIZED) {
2621                 struct inode_security_struct *isec = inode->i_security;
2622                 isec->sclass = inode_mode_to_security_class(inode->i_mode);
2623                 isec->sid = newsid;
2624                 isec->initialized = 1;
2625         }
2626
2627         if (!ss_initialized || !(sbsec->flags & SE_SBLABELSUPP))
2628                 return -EOPNOTSUPP;
2629
2630         if (name) {
2631                 namep = kstrdup(XATTR_SELINUX_SUFFIX, GFP_NOFS);
2632                 if (!namep)
2633                         return -ENOMEM;
2634                 *name = namep;
2635         }
2636
2637         if (value && len) {
2638                 rc = security_sid_to_context_force(newsid, &context, &clen);
2639                 if (rc) {
2640                         kfree(namep);
2641                         return rc;
2642                 }
2643                 *value = context;
2644                 *len = clen;
2645         }
2646
2647         return 0;
2648 }
2649
2650 static int selinux_inode_create(struct inode *dir, struct dentry *dentry, int mask)
2651 {
2652         return may_create(dir, dentry, SECCLASS_FILE);
2653 }
2654
2655 static int selinux_inode_link(struct dentry *old_dentry, struct inode *dir, struct dentry *new_dentry)
2656 {
2657         return may_link(dir, old_dentry, MAY_LINK);
2658 }
2659
2660 static int selinux_inode_unlink(struct inode *dir, struct dentry *dentry)
2661 {
2662         return may_link(dir, dentry, MAY_UNLINK);
2663 }
2664
2665 static int selinux_inode_symlink(struct inode *dir, struct dentry *dentry, const char *name)
2666 {
2667         return may_create(dir, dentry, SECCLASS_LNK_FILE);
2668 }
2669
2670 static int selinux_inode_mkdir(struct inode *dir, struct dentry *dentry, int mask)
2671 {
2672         return may_create(dir, dentry, SECCLASS_DIR);
2673 }
2674
2675 static int selinux_inode_rmdir(struct inode *dir, struct dentry *dentry)
2676 {
2677         return may_link(dir, dentry, MAY_RMDIR);
2678 }
2679
2680 static int selinux_inode_mknod(struct inode *dir, struct dentry *dentry, int mode, dev_t dev)
2681 {
2682         return may_create(dir, dentry, inode_mode_to_security_class(mode));
2683 }
2684
2685 static int selinux_inode_rename(struct inode *old_inode, struct dentry *old_dentry,
2686                                 struct inode *new_inode, struct dentry *new_dentry)
2687 {
2688         return may_rename(old_inode, old_dentry, new_inode, new_dentry);
2689 }
2690
2691 static int selinux_inode_readlink(struct dentry *dentry)
2692 {
2693         const struct cred *cred = current_cred();
2694
2695         return dentry_has_perm(cred, NULL, dentry, FILE__READ);
2696 }
2697
2698 static int selinux_inode_follow_link(struct dentry *dentry, struct nameidata *nameidata)
2699 {
2700         const struct cred *cred = current_cred();
2701
2702         return dentry_has_perm(cred, NULL, dentry, FILE__READ);
2703 }
2704
2705 static int selinux_inode_permission(struct inode *inode, int mask)
2706 {
2707         const struct cred *cred = current_cred();
2708
2709         if (!mask) {
2710                 /* No permission to check.  Existence test. */
2711                 return 0;
2712         }
2713
2714         return inode_has_perm(cred, inode,
2715                               file_mask_to_av(inode->i_mode, mask), NULL);
2716 }
2717
2718 static int selinux_inode_setattr(struct dentry *dentry, struct iattr *iattr)
2719 {
2720         const struct cred *cred = current_cred();
2721
2722         if (iattr->ia_valid & ATTR_FORCE)
2723                 return 0;
2724
2725         if (iattr->ia_valid & (ATTR_MODE | ATTR_UID | ATTR_GID |
2726                                ATTR_ATIME_SET | ATTR_MTIME_SET))
2727                 return dentry_has_perm(cred, NULL, dentry, FILE__SETATTR);
2728
2729         return dentry_has_perm(cred, NULL, dentry, FILE__WRITE);
2730 }
2731
2732 static int selinux_inode_getattr(struct vfsmount *mnt, struct dentry *dentry)
2733 {
2734         const struct cred *cred = current_cred();
2735
2736         return dentry_has_perm(cred, mnt, dentry, FILE__GETATTR);
2737 }
2738
2739 static int selinux_inode_setotherxattr(struct dentry *dentry, const char *name)
2740 {
2741         const struct cred *cred = current_cred();
2742
2743         if (!strncmp(name, XATTR_SECURITY_PREFIX,
2744                      sizeof XATTR_SECURITY_PREFIX - 1)) {
2745                 if (!strcmp(name, XATTR_NAME_CAPS)) {
2746                         if (!capable(CAP_SETFCAP))
2747                                 return -EPERM;
2748                 } else if (!capable(CAP_SYS_ADMIN)) {
2749                         /* A different attribute in the security namespace.
2750                            Restrict to administrator. */
2751                         return -EPERM;
2752                 }
2753         }
2754
2755         /* Not an attribute we recognize, so just check the
2756            ordinary setattr permission. */
2757         return dentry_has_perm(cred, NULL, dentry, FILE__SETATTR);
2758 }
2759
2760 static int selinux_inode_setxattr(struct dentry *dentry, const char *name,
2761                                   const void *value, size_t size, int flags)
2762 {
2763         struct inode *inode = dentry->d_inode;
2764         struct inode_security_struct *isec = inode->i_security;
2765         struct superblock_security_struct *sbsec;
2766         struct avc_audit_data ad;
2767         u32 newsid, sid = current_sid();
2768         int rc = 0;
2769
2770         if (strcmp(name, XATTR_NAME_SELINUX))
2771                 return selinux_inode_setotherxattr(dentry, name);
2772
2773         sbsec = inode->i_sb->s_security;
2774         if (!(sbsec->flags & SE_SBLABELSUPP))
2775                 return -EOPNOTSUPP;
2776
2777         if (!is_owner_or_cap(inode))
2778                 return -EPERM;
2779
2780         AVC_AUDIT_DATA_INIT(&ad, FS);
2781         ad.u.fs.path.dentry = dentry;
2782
2783         rc = avc_has_perm(sid, isec->sid, isec->sclass,
2784                           FILE__RELABELFROM, &ad);
2785         if (rc)
2786                 return rc;
2787
2788         rc = security_context_to_sid(value, size, &newsid);
2789         if (rc == -EINVAL) {
2790                 if (!capable(CAP_MAC_ADMIN))
2791                         return rc;
2792                 rc = security_context_to_sid_force(value, size, &newsid);
2793         }
2794         if (rc)
2795                 return rc;
2796
2797         rc = avc_has_perm(sid, newsid, isec->sclass,
2798                           FILE__RELABELTO, &ad);
2799         if (rc)
2800                 return rc;
2801
2802         rc = security_validate_transition(isec->sid, newsid, sid,
2803                                           isec->sclass);
2804         if (rc)
2805                 return rc;
2806
2807         return avc_has_perm(newsid,
2808                             sbsec->sid,
2809                             SECCLASS_FILESYSTEM,
2810                             FILESYSTEM__ASSOCIATE,
2811                             &ad);
2812 }
2813
2814 static void selinux_inode_post_setxattr(struct dentry *dentry, const char *name,
2815                                         const void *value, size_t size,
2816                                         int flags)
2817 {
2818         struct inode *inode = dentry->d_inode;
2819         struct inode_security_struct *isec = inode->i_security;
2820         u32 newsid;
2821         int rc;
2822
2823         if (strcmp(name, XATTR_NAME_SELINUX)) {
2824                 /* Not an attribute we recognize, so nothing to do. */
2825                 return;
2826         }
2827
2828         rc = security_context_to_sid_force(value, size, &newsid);
2829         if (rc) {
2830                 printk(KERN_ERR "SELinux:  unable to map context to SID"
2831                        "for (%s, %lu), rc=%d\n",
2832                        inode->i_sb->s_id, inode->i_ino, -rc);
2833                 return;
2834         }
2835
2836         isec->sid = newsid;
2837         return;
2838 }
2839
2840 static int selinux_inode_getxattr(struct dentry *dentry, const char *name)
2841 {
2842         const struct cred *cred = current_cred();
2843
2844         return dentry_has_perm(cred, NULL, dentry, FILE__GETATTR);
2845 }
2846
2847 static int selinux_inode_listxattr(struct dentry *dentry)
2848 {
2849         const struct cred *cred = current_cred();
2850
2851         return dentry_has_perm(cred, NULL, dentry, FILE__GETATTR);
2852 }
2853
2854 static int selinux_inode_removexattr(struct dentry *dentry, const char *name)
2855 {
2856         if (strcmp(name, XATTR_NAME_SELINUX))
2857                 return selinux_inode_setotherxattr(dentry, name);
2858
2859         /* No one is allowed to remove a SELinux security label.
2860            You can change the label, but all data must be labeled. */
2861         return -EACCES;
2862 }
2863
2864 /*
2865  * Copy the inode security context value to the user.
2866  *
2867  * Permission check is handled by selinux_inode_getxattr hook.
2868  */
2869 static int selinux_inode_getsecurity(const struct inode *inode, const char *name, void **buffer, bool alloc)
2870 {
2871         u32 size;
2872         int error;
2873         char *context = NULL;
2874         struct inode_security_struct *isec = inode->i_security;
2875
2876         if (strcmp(name, XATTR_SELINUX_SUFFIX))
2877                 return -EOPNOTSUPP;
2878
2879         /*
2880          * If the caller has CAP_MAC_ADMIN, then get the raw context
2881          * value even if it is not defined by current policy; otherwise,
2882          * use the in-core value under current policy.
2883          * Use the non-auditing forms of the permission checks since
2884          * getxattr may be called by unprivileged processes commonly
2885          * and lack of permission just means that we fall back to the
2886          * in-core context value, not a denial.
2887          */
2888         error = selinux_capable(current, current_cred(), CAP_MAC_ADMIN,
2889                                 SECURITY_CAP_NOAUDIT);
2890         if (!error)
2891                 error = security_sid_to_context_force(isec->sid, &context,
2892                                                       &size);
2893         else
2894                 error = security_sid_to_context(isec->sid, &context, &size);
2895         if (error)
2896                 return error;
2897         error = size;
2898         if (alloc) {
2899                 *buffer = context;
2900                 goto out_nofree;
2901         }
2902         kfree(context);
2903 out_nofree:
2904         return error;
2905 }
2906
2907 static int selinux_inode_setsecurity(struct inode *inode, const char *name,
2908                                      const void *value, size_t size, int flags)
2909 {
2910         struct inode_security_struct *isec = inode->i_security;
2911         u32 newsid;
2912         int rc;
2913
2914         if (strcmp(name, XATTR_SELINUX_SUFFIX))
2915                 return -EOPNOTSUPP;
2916
2917         if (!value || !size)
2918                 return -EACCES;
2919
2920         rc = security_context_to_sid((void *)value, size, &newsid);
2921         if (rc)
2922                 return rc;
2923
2924         isec->sid = newsid;
2925         return 0;
2926 }
2927
2928 static int selinux_inode_listsecurity(struct inode *inode, char *buffer, size_t buffer_size)
2929 {
2930         const int len = sizeof(XATTR_NAME_SELINUX);
2931         if (buffer && len <= buffer_size)
2932                 memcpy(buffer, XATTR_NAME_SELINUX, len);
2933         return len;
2934 }
2935
2936 static void selinux_inode_getsecid(const struct inode *inode, u32 *secid)
2937 {
2938         struct inode_security_struct *isec = inode->i_security;
2939         *secid = isec->sid;
2940 }
2941
2942 /* file security operations */
2943
2944 static int selinux_revalidate_file_permission(struct file *file, int mask)
2945 {
2946         const struct cred *cred = current_cred();
2947         struct inode *inode = file->f_path.dentry->d_inode;
2948
2949         if (!mask) {
2950                 /* No permission to check.  Existence test. */
2951                 return 0;
2952         }
2953
2954         /* file_mask_to_av won't add FILE__WRITE if MAY_APPEND is set */
2955         if ((file->f_flags & O_APPEND) && (mask & MAY_WRITE))
2956                 mask |= MAY_APPEND;
2957
2958         return file_has_perm(cred, file,
2959                              file_mask_to_av(inode->i_mode, mask));
2960 }
2961
2962 static int selinux_file_permission(struct file *file, int mask)
2963 {
2964         if (!mask)
2965                 /* No permission to check.  Existence test. */
2966                 return 0;
2967
2968         return selinux_revalidate_file_permission(file, mask);
2969 }
2970
2971 static int selinux_file_alloc_security(struct file *file)
2972 {
2973         return file_alloc_security(file);
2974 }
2975
2976 static void selinux_file_free_security(struct file *file)
2977 {
2978         file_free_security(file);
2979 }
2980
2981 static int selinux_file_ioctl(struct file *file, unsigned int cmd,
2982                               unsigned long arg)
2983 {
2984         const struct cred *cred = current_cred();
2985         u32 av = 0;
2986
2987         if (_IOC_DIR(cmd) & _IOC_WRITE)
2988                 av |= FILE__WRITE;
2989         if (_IOC_DIR(cmd) & _IOC_READ)
2990                 av |= FILE__READ;
2991         if (!av)
2992                 av = FILE__IOCTL;
2993
2994         return file_has_perm(cred, file, av);
2995 }
2996
2997 static int file_map_prot_check(struct file *file, unsigned long prot, int shared)
2998 {
2999         const struct cred *cred = current_cred();
3000         int rc = 0;
3001
3002 #ifndef CONFIG_PPC32
3003         if ((prot & PROT_EXEC) && (!file || (!shared && (prot & PROT_WRITE)))) {
3004                 /*
3005                  * We are making executable an anonymous mapping or a
3006                  * private file mapping that will also be writable.
3007                  * This has an additional check.
3008                  */
3009                 rc = cred_has_perm(cred, cred, PROCESS__EXECMEM);
3010                 if (rc)
3011                         goto error;
3012         }
3013 #endif
3014
3015         if (file) {
3016                 /* read access is always possible with a mapping */
3017                 u32 av = FILE__READ;
3018
3019                 /* write access only matters if the mapping is shared */
3020                 if (shared && (prot & PROT_WRITE))
3021                         av |= FILE__WRITE;
3022
3023                 if (prot & PROT_EXEC)
3024                         av |= FILE__EXECUTE;
3025
3026                 return file_has_perm(cred, file, av);
3027         }
3028
3029 error:
3030         return rc;
3031 }
3032
3033 static int selinux_file_mmap(struct file *file, unsigned long reqprot,
3034                              unsigned long prot, unsigned long flags,
3035                              unsigned long addr, unsigned long addr_only)
3036 {
3037         int rc = 0;
3038         u32 sid = current_sid();
3039
3040         if (addr < mmap_min_addr)
3041                 rc = avc_has_perm(sid, sid, SECCLASS_MEMPROTECT,
3042                                   MEMPROTECT__MMAP_ZERO, NULL);
3043         if (rc || addr_only)
3044                 return rc;
3045
3046         if (selinux_checkreqprot)
3047                 prot = reqprot;
3048
3049         return file_map_prot_check(file, prot,
3050                                    (flags & MAP_TYPE) == MAP_SHARED);
3051 }
3052
3053 static int selinux_file_mprotect(struct vm_area_struct *vma,
3054                                  unsigned long reqprot,
3055                                  unsigned long prot)
3056 {
3057         const struct cred *cred = current_cred();
3058
3059         if (selinux_checkreqprot)
3060                 prot = reqprot;
3061
3062 #ifndef CONFIG_PPC32
3063         if ((prot & PROT_EXEC) && !(vma->vm_flags & VM_EXEC)) {
3064                 int rc = 0;
3065                 if (vma->vm_start >= vma->vm_mm->start_brk &&
3066                     vma->vm_end <= vma->vm_mm->brk) {
3067                         rc = cred_has_perm(cred, cred, PROCESS__EXECHEAP);
3068                 } else if (!vma->vm_file &&
3069                            vma->vm_start <= vma->vm_mm->start_stack &&
3070                            vma->vm_end >= vma->vm_mm->start_stack) {
3071                         rc = current_has_perm(current, PROCESS__EXECSTACK);
3072                 } else if (vma->vm_file && vma->anon_vma) {
3073                         /*
3074                          * We are making executable a file mapping that has
3075                          * had some COW done. Since pages might have been
3076                          * written, check ability to execute the possibly
3077                          * modified content.  This typically should only
3078                          * occur for text relocations.
3079                          */
3080                         rc = file_has_perm(cred, vma->vm_file, FILE__EXECMOD);
3081                 }
3082                 if (rc)
3083                         return rc;
3084         }
3085 #endif
3086
3087         return file_map_prot_check(vma->vm_file, prot, vma->vm_flags&VM_SHARED);
3088 }
3089
3090 static int selinux_file_lock(struct file *file, unsigned int cmd)
3091 {
3092         const struct cred *cred = current_cred();
3093
3094         return file_has_perm(cred, file, FILE__LOCK);
3095 }
3096
3097 static int selinux_file_fcntl(struct file *file, unsigned int cmd,
3098                               unsigned long arg)
3099 {
3100         const struct cred *cred = current_cred();
3101         int err = 0;
3102
3103         switch (cmd) {
3104         case F_SETFL:
3105                 if (!file->f_path.dentry || !file->f_path.dentry->d_inode) {
3106                         err = -EINVAL;
3107                         break;
3108                 }
3109
3110                 if ((file->f_flags & O_APPEND) && !(arg & O_APPEND)) {
3111                         err = file_has_perm(cred, file, FILE__WRITE);
3112                         break;
3113                 }
3114                 /* fall through */
3115         case F_SETOWN:
3116         case F_SETSIG:
3117         case F_GETFL:
3118         case F_GETOWN:
3119         case F_GETSIG:
3120                 /* Just check FD__USE permission */
3121                 err = file_has_perm(cred, file, 0);
3122                 break;
3123         case F_GETLK:
3124         case F_SETLK:
3125         case F_SETLKW:
3126 #if BITS_PER_LONG == 32
3127         case F_GETLK64:
3128         case F_SETLK64:
3129         case F_SETLKW64:
3130 #endif
3131                 if (!file->f_path.dentry || !file->f_path.dentry->d_inode) {
3132                         err = -EINVAL;
3133                         break;
3134                 }
3135                 err = file_has_perm(cred, file, FILE__LOCK);
3136                 break;
3137         }
3138
3139         return err;
3140 }
3141
3142 static int selinux_file_set_fowner(struct file *file)
3143 {
3144         struct file_security_struct *fsec;
3145
3146         fsec = file->f_security;
3147         fsec->fown_sid = current_sid();
3148
3149         return 0;
3150 }
3151
3152 static int selinux_file_send_sigiotask(struct task_struct *tsk,
3153                                        struct fown_struct *fown, int signum)
3154 {
3155         struct file *file;
3156         u32 sid = current_sid();
3157         u32 perm;
3158         struct file_security_struct *fsec;
3159
3160         /* struct fown_struct is never outside the context of a struct file */
3161         file = container_of(fown, struct file, f_owner);
3162
3163         fsec = file->f_security;
3164
3165         if (!signum)
3166                 perm = signal_to_av(SIGIO); /* as per send_sigio_to_task */
3167         else
3168                 perm = signal_to_av(signum);
3169
3170         return avc_has_perm(fsec->fown_sid, sid,
3171                             SECCLASS_PROCESS, perm, NULL);
3172 }
3173
3174 static int selinux_file_receive(struct file *file)
3175 {
3176         const struct cred *cred = current_cred();
3177
3178         return file_has_perm(cred, file, file_to_av(file));
3179 }
3180
3181 static int selinux_dentry_open(struct file *file, const struct cred *cred)
3182 {
3183         struct file_security_struct *fsec;
3184         struct inode *inode;
3185         struct inode_security_struct *isec;
3186
3187         inode = file->f_path.dentry->d_inode;
3188         fsec = file->f_security;
3189         isec = inode->i_security;
3190         /*
3191          * Save inode label and policy sequence number
3192          * at open-time so that selinux_file_permission
3193          * can determine whether revalidation is necessary.
3194          * Task label is already saved in the file security
3195          * struct as its SID.
3196          */
3197         fsec->isid = isec->sid;
3198         fsec->pseqno = avc_policy_seqno();
3199         /*
3200          * Since the inode label or policy seqno may have changed
3201          * between the selinux_inode_permission check and the saving
3202          * of state above, recheck that access is still permitted.
3203          * Otherwise, access might never be revalidated against the
3204          * new inode label or new policy.
3205          * This check is not redundant - do not remove.
3206          */
3207         return inode_has_perm(cred, inode, open_file_to_av(file), NULL);
3208 }
3209
3210 /* task security operations */
3211
3212 static int selinux_task_create(unsigned long clone_flags)
3213 {
3214         return current_has_perm(current, PROCESS__FORK);
3215 }
3216
3217 /*
3218  * detach and free the LSM part of a set of credentials
3219  */
3220 static void selinux_cred_free(struct cred *cred)
3221 {
3222         struct task_security_struct *tsec = cred->security;
3223         cred->security = NULL;
3224         kfree(tsec);
3225 }
3226
3227 /*
3228  * prepare a new set of credentials for modification
3229  */
3230 static int selinux_cred_prepare(struct cred *new, const struct cred *old,
3231                                 gfp_t gfp)
3232 {
3233         const struct task_security_struct *old_tsec;
3234         struct task_security_struct *tsec;
3235
3236         old_tsec = old->security;
3237
3238         tsec = kmemdup(old_tsec, sizeof(struct task_security_struct), gfp);
3239         if (!tsec)
3240                 return -ENOMEM;
3241
3242         new->security = tsec;
3243         return 0;
3244 }
3245
3246 /*
3247  * set the security data for a kernel service
3248  * - all the creation contexts are set to unlabelled
3249  */
3250 static int selinux_kernel_act_as(struct cred *new, u32 secid)
3251 {
3252         struct task_security_struct *tsec = new->security;
3253         u32 sid = current_sid();
3254         int ret;
3255
3256         ret = avc_has_perm(sid, secid,
3257                            SECCLASS_KERNEL_SERVICE,
3258                            KERNEL_SERVICE__USE_AS_OVERRIDE,
3259                            NULL);
3260         if (ret == 0) {
3261                 tsec->sid = secid;
3262                 tsec->create_sid = 0;
3263                 tsec->keycreate_sid = 0;
3264                 tsec->sockcreate_sid = 0;
3265         }
3266         return ret;
3267 }
3268
3269 /*
3270  * set the file creation context in a security record to the same as the
3271  * objective context of the specified inode
3272  */
3273 static int selinux_kernel_create_files_as(struct cred *new, struct inode *inode)
3274 {
3275         struct inode_security_struct *isec = inode->i_security;
3276         struct task_security_struct *tsec = new->security;
3277         u32 sid = current_sid();
3278         int ret;
3279
3280         ret = avc_has_perm(sid, isec->sid,
3281                            SECCLASS_KERNEL_SERVICE,
3282                            KERNEL_SERVICE__CREATE_FILES_AS,
3283                            NULL);
3284
3285         if (ret == 0)
3286                 tsec->create_sid = isec->sid;
3287         return 0;
3288 }
3289
3290 static int selinux_task_setpgid(struct task_struct *p, pid_t pgid)
3291 {
3292         return current_has_perm(p, PROCESS__SETPGID);
3293 }
3294
3295 static int selinux_task_getpgid(struct task_struct *p)
3296 {
3297         return current_has_perm(p, PROCESS__GETPGID);
3298 }
3299
3300 static int selinux_task_getsid(struct task_struct *p)
3301 {
3302         return current_has_perm(p, PROCESS__GETSESSION);
3303 }
3304
3305 static void selinux_task_getsecid(struct task_struct *p, u32 *secid)
3306 {
3307         *secid = task_sid(p);
3308 }
3309
3310 static int selinux_task_setnice(struct task_struct *p, int nice)
3311 {
3312         int rc;
3313
3314         rc = cap_task_setnice(p, nice);
3315         if (rc)
3316                 return rc;
3317
3318         return current_has_perm(p, PROCESS__SETSCHED);
3319 }
3320
3321 static int selinux_task_setioprio(struct task_struct *p, int ioprio)
3322 {
3323         int rc;
3324
3325         rc = cap_task_setioprio(p, ioprio);
3326         if (rc)
3327                 return rc;
3328
3329         return current_has_perm(p, PROCESS__SETSCHED);
3330 }
3331
3332 static int selinux_task_getioprio(struct task_struct *p)
3333 {
3334         return current_has_perm(p, PROCESS__GETSCHED);
3335 }
3336
3337 static int selinux_task_setrlimit(unsigned int resource, struct rlimit *new_rlim)
3338 {
3339         struct rlimit *old_rlim = current->signal->rlim + resource;
3340
3341         /* Control the ability to change the hard limit (whether
3342            lowering or raising it), so that the hard limit can
3343            later be used as a safe reset point for the soft limit
3344            upon context transitions.  See selinux_bprm_committing_creds. */
3345         if (old_rlim->rlim_max != new_rlim->rlim_max)
3346                 return current_has_perm(current, PROCESS__SETRLIMIT);
3347
3348         return 0;
3349 }
3350
3351 static int selinux_task_setscheduler(struct task_struct *p, int policy, struct sched_param *lp)
3352 {
3353         int rc;
3354
3355         rc = cap_task_setscheduler(p, policy, lp);
3356         if (rc)
3357                 return rc;
3358
3359         return current_has_perm(p, PROCESS__SETSCHED);
3360 }
3361
3362 static int selinux_task_getscheduler(struct task_struct *p)
3363 {
3364         return current_has_perm(p, PROCESS__GETSCHED);
3365 }
3366
3367 static int selinux_task_movememory(struct task_struct *p)
3368 {
3369         return current_has_perm(p, PROCESS__SETSCHED);
3370 }
3371
3372 static int selinux_task_kill(struct task_struct *p, struct siginfo *info,
3373                                 int sig, u32 secid)
3374 {
3375         u32 perm;
3376         int rc;
3377
3378         if (!sig)
3379                 perm = PROCESS__SIGNULL; /* null signal; existence test */
3380         else
3381                 perm = signal_to_av(sig);
3382         if (secid)
3383                 rc = avc_has_perm(secid, task_sid(p),
3384                                   SECCLASS_PROCESS, perm, NULL);
3385         else
3386                 rc = current_has_perm(p, perm);
3387         return rc;
3388 }
3389
3390 static int selinux_task_wait(struct task_struct *p)
3391 {
3392         return task_has_perm(p, current, PROCESS__SIGCHLD);
3393 }
3394
3395 static void selinux_task_to_inode(struct task_struct *p,
3396                                   struct inode *inode)
3397 {
3398         struct inode_security_struct *isec = inode->i_security;
3399         u32 sid = task_sid(p);
3400
3401         isec->sid = sid;
3402         isec->initialized = 1;
3403 }
3404
3405 /* Returns error only if unable to parse addresses */
3406 static int selinux_parse_skb_ipv4(struct sk_buff *skb,
3407                         struct avc_audit_data *ad, u8 *proto)
3408 {
3409         int offset, ihlen, ret = -EINVAL;
3410         struct iphdr _iph, *ih;
3411
3412         offset = skb_network_offset(skb);
3413         ih = skb_header_pointer(skb, offset, sizeof(_iph), &_iph);
3414         if (ih == NULL)
3415                 goto out;
3416
3417         ihlen = ih->ihl * 4;
3418         if (ihlen < sizeof(_iph))
3419                 goto out;
3420
3421         ad->u.net.v4info.saddr = ih->saddr;
3422         ad->u.net.v4info.daddr = ih->daddr;
3423         ret = 0;
3424
3425         if (proto)
3426                 *proto = ih->protocol;
3427
3428         switch (ih->protocol) {
3429         case IPPROTO_TCP: {
3430                 struct tcphdr _tcph, *th;
3431
3432                 if (ntohs(ih->frag_off) & IP_OFFSET)
3433                         break;
3434
3435                 offset += ihlen;
3436                 th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph);
3437                 if (th == NULL)
3438                         break;
3439
3440                 ad->u.net.sport = th->source;
3441                 ad->u.net.dport = th->dest;
3442                 break;
3443         }
3444
3445         case IPPROTO_UDP: {
3446                 struct udphdr _udph, *uh;
3447
3448                 if (ntohs(ih->frag_off) & IP_OFFSET)
3449                         break;
3450
3451                 offset += ihlen;
3452                 uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph);
3453                 if (uh == NULL)
3454                         break;
3455
3456                 ad->u.net.sport = uh->source;
3457                 ad->u.net.dport = uh->dest;
3458                 break;
3459         }
3460
3461         case IPPROTO_DCCP: {
3462                 struct dccp_hdr _dccph, *dh;
3463
3464                 if (ntohs(ih->frag_off) & IP_OFFSET)
3465                         break;
3466
3467                 offset += ihlen;
3468                 dh = skb_header_pointer(skb, offset, sizeof(_dccph), &_dccph);
3469                 if (dh == NULL)
3470                         break;
3471
3472                 ad->u.net.sport = dh->dccph_sport;
3473                 ad->u.net.dport = dh->dccph_dport;
3474                 break;
3475         }
3476
3477         default:
3478                 break;
3479         }
3480 out:
3481         return ret;
3482 }
3483
3484 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
3485
3486 /* Returns error only if unable to parse addresses */
3487 static int selinux_parse_skb_ipv6(struct sk_buff *skb,
3488                         struct avc_audit_data *ad, u8 *proto)
3489 {
3490         u8 nexthdr;
3491         int ret = -EINVAL, offset;
3492         struct ipv6hdr _ipv6h, *ip6;
3493
3494         offset = skb_network_offset(skb);
3495         ip6 = skb_header_pointer(skb, offset, sizeof(_ipv6h), &_ipv6h);
3496         if (ip6 == NULL)
3497                 goto out;
3498
3499         ipv6_addr_copy(&ad->u.net.v6info.saddr, &ip6->saddr);
3500         ipv6_addr_copy(&ad->u.net.v6info.daddr, &ip6->daddr);
3501         ret = 0;
3502
3503         nexthdr = ip6->nexthdr;
3504         offset += sizeof(_ipv6h);
3505         offset = ipv6_skip_exthdr(skb, offset, &nexthdr);
3506         if (offset < 0)
3507                 goto out;
3508
3509         if (proto)
3510                 *proto = nexthdr;
3511
3512         switch (nexthdr) {
3513         case IPPROTO_TCP: {
3514                 struct tcphdr _tcph, *th;
3515
3516                 th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph);
3517                 if (th == NULL)
3518                         break;
3519
3520                 ad->u.net.sport = th->source;
3521                 ad->u.net.dport = th->dest;
3522                 break;
3523         }
3524
3525         case IPPROTO_UDP: {
3526                 struct udphdr _udph, *uh;
3527
3528                 uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph);
3529                 if (uh == NULL)
3530                         break;
3531
3532                 ad->u.net.sport = uh->source;
3533                 ad->u.net.dport = uh->dest;
3534                 break;
3535         }
3536
3537         case IPPROTO_DCCP: {
3538                 struct dccp_hdr _dccph, *dh;
3539
3540                 dh = skb_header_pointer(skb, offset, sizeof(_dccph), &_dccph);
3541                 if (dh == NULL)
3542                         break;
3543
3544                 ad->u.net.sport = dh->dccph_sport;
3545                 ad->u.net.dport = dh->dccph_dport;
3546                 break;
3547         }
3548
3549         /* includes fragments */
3550         default:
3551                 break;
3552         }
3553 out:
3554         return ret;
3555 }
3556
3557 #endif /* IPV6 */
3558
3559 static int selinux_parse_skb(struct sk_buff *skb, struct avc_audit_data *ad,
3560                              char **_addrp, int src, u8 *proto)
3561 {
3562         char *addrp;
3563         int ret;
3564
3565         switch (ad->u.net.family) {
3566         case PF_INET:
3567                 ret = selinux_parse_skb_ipv4(skb, ad, proto);
3568                 if (ret)
3569                         goto parse_error;
3570                 addrp = (char *)(src ? &ad->u.net.v4info.saddr :
3571                                        &ad->u.net.v4info.daddr);
3572                 goto okay;
3573
3574 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
3575         case PF_INET6:
3576                 ret = selinux_parse_skb_ipv6(skb, ad, proto);
3577                 if (ret)
3578                         goto parse_error;
3579                 addrp = (char *)(src ? &ad->u.net.v6info.saddr :
3580                                        &ad->u.net.v6info.daddr);
3581                 goto okay;
3582 #endif  /* IPV6 */
3583         default:
3584                 addrp = NULL;
3585                 goto okay;
3586         }
3587
3588 parse_error:
3589         printk(KERN_WARNING
3590                "SELinux: failure in selinux_parse_skb(),"
3591                " unable to parse packet\n");
3592         return ret;
3593
3594 okay:
3595         if (_addrp)
3596                 *_addrp = addrp;
3597         return 0;
3598 }
3599
3600 /**
3601  * selinux_skb_peerlbl_sid - Determine the peer label of a packet
3602  * @skb: the packet
3603  * @family: protocol family
3604  * @sid: the packet's peer label SID
3605  *
3606  * Description:
3607  * Check the various different forms of network peer labeling and determine
3608  * the peer label/SID for the packet; most of the magic actually occurs in
3609  * the security server function security_net_peersid_cmp().  The function
3610  * returns zero if the value in @sid is valid (although it may be SECSID_NULL)
3611  * or -EACCES if @sid is invalid due to inconsistencies with the different
3612  * peer labels.
3613  *
3614  */
3615 static int selinux_skb_peerlbl_sid(struct sk_buff *skb, u16 family, u32 *sid)
3616 {
3617         int err;
3618         u32 xfrm_sid;
3619         u32 nlbl_sid;
3620         u32 nlbl_type;
3621
3622         selinux_skb_xfrm_sid(skb, &xfrm_sid);
3623         selinux_netlbl_skbuff_getsid(skb, family, &nlbl_type, &nlbl_sid);
3624
3625         err = security_net_peersid_resolve(nlbl_sid, nlbl_type, xfrm_sid, sid);
3626         if (unlikely(err)) {
3627                 printk(KERN_WARNING
3628                        "SELinux: failure in selinux_skb_peerlbl_sid(),"
3629                        " unable to determine packet's peer label\n");
3630                 return -EACCES;
3631         }
3632
3633         return 0;
3634 }
3635
3636 /* socket security operations */
3637 static int socket_has_perm(struct task_struct *task, struct socket *sock,
3638                            u32 perms)
3639 {
3640         struct inode_security_struct *isec;
3641         struct avc_audit_data ad;
3642         u32 sid;
3643         int err = 0;
3644
3645         isec = SOCK_INODE(sock)->i_security;
3646
3647         if (isec->sid == SECINITSID_KERNEL)
3648                 goto out;
3649         sid = task_sid(task);
3650
3651         AVC_AUDIT_DATA_INIT(&ad, NET);
3652         ad.u.net.sk = sock->sk;
3653         err = avc_has_perm(sid, isec->sid, isec->sclass, perms, &ad);
3654
3655 out:
3656         return err;
3657 }
3658
3659 static int selinux_socket_create(int family, int type,
3660                                  int protocol, int kern)
3661 {
3662         const struct cred *cred = current_cred();
3663         const struct task_security_struct *tsec = cred->security;
3664         u32 sid, newsid;
3665         u16 secclass;
3666         int err = 0;
3667
3668         if (kern)
3669                 goto out;
3670
3671         sid = tsec->sid;
3672         newsid = tsec->sockcreate_sid ?: sid;
3673
3674         secclass = socket_type_to_security_class(family, type, protocol);
3675         err = avc_has_perm(sid, newsid, secclass, SOCKET__CREATE, NULL);
3676
3677 out:
3678         return err;
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 cred *cred = current_cred();
3685         const struct task_security_struct *tsec = cred->security;
3686         struct inode_security_struct *isec;
3687         struct sk_security_struct *sksec;
3688         u32 sid, newsid;
3689         int err = 0;
3690
3691         sid = tsec->sid;
3692         newsid = tsec->sockcreate_sid;
3693
3694         isec = SOCK_INODE(sock)->i_security;
3695
3696         if (kern)
3697                 isec->sid = SECINITSID_KERNEL;
3698         else if (newsid)
3699                 isec->sid = newsid;
3700         else
3701                 isec->sid = sid;
3702
3703         isec->sclass = socket_type_to_security_class(family, type, protocol);
3704         isec->initialized = 1;
3705
3706         if (sock->sk) {
3707                 sksec = sock->sk->sk_security;
3708                 sksec->sid = isec->sid;
3709                 sksec->sclass = isec->sclass;
3710                 err = selinux_netlbl_socket_post_create(sock->sk, family);
3711         }
3712
3713         return err;
3714 }
3715
3716 /* Range of port numbers used to automatically bind.
3717    Need to determine whether we should perform a name_bind
3718    permission check between the socket and the port number. */
3719
3720 static int selinux_socket_bind(struct socket *sock, struct sockaddr *address, int addrlen)
3721 {
3722         u16 family;
3723         int err;
3724
3725         err = socket_has_perm(current, sock, SOCKET__BIND);
3726         if (err)
3727                 goto out;
3728
3729         /*
3730          * If PF_INET or PF_INET6, check name_bind permission for the port.
3731          * Multiple address binding for SCTP is not supported yet: we just
3732          * check the first address now.
3733          */
3734         family = sock->sk->sk_family;
3735         if (family == PF_INET || family == PF_INET6) {
3736                 char *addrp;
3737                 struct inode_security_struct *isec;
3738                 struct avc_audit_data ad;
3739                 struct sockaddr_in *addr4 = NULL;
3740                 struct sockaddr_in6 *addr6 = NULL;
3741                 unsigned short snum;
3742                 struct sock *sk = sock->sk;
3743                 u32 sid, node_perm;
3744
3745                 isec = SOCK_INODE(sock)->i_security;
3746
3747                 if (family == PF_INET) {
3748                         addr4 = (struct sockaddr_in *)address;
3749                         snum = ntohs(addr4->sin_port);
3750                         addrp = (char *)&addr4->sin_addr.s_addr;
3751                 } else {
3752                         addr6 = (struct sockaddr_in6 *)address;
3753                         snum = ntohs(addr6->sin6_port);
3754                         addrp = (char *)&addr6->sin6_addr.s6_addr;
3755                 }
3756
3757                 if (snum) {
3758                         int low, high;
3759
3760                         inet_get_local_port_range(&low, &high);
3761
3762                         if (snum < max(PROT_SOCK, low) || snum > high) {
3763                                 err = sel_netport_sid(sk->sk_protocol,
3764                                                       snum, &sid);
3765                                 if (err)
3766                                         goto out;
3767                                 AVC_AUDIT_DATA_INIT(&ad, NET);
3768                                 ad.u.net.sport = htons(snum);
3769                                 ad.u.net.family = family;
3770                                 err = avc_has_perm(isec->sid, sid,
3771                                                    isec->sclass,
3772                                                    SOCKET__NAME_BIND, &ad);
3773                                 if (err)
3774                                         goto out;
3775                         }
3776                 }
3777
3778                 switch (isec->sclass) {
3779                 case SECCLASS_TCP_SOCKET:
3780                         node_perm = TCP_SOCKET__NODE_BIND;
3781                         break;
3782
3783                 case SECCLASS_UDP_SOCKET:
3784                         node_perm = UDP_SOCKET__NODE_BIND;
3785                         break;
3786
3787                 case SECCLASS_DCCP_SOCKET:
3788                         node_perm = DCCP_SOCKET__NODE_BIND;
3789                         break;
3790
3791                 default:
3792                         node_perm = RAWIP_SOCKET__NODE_BIND;
3793                         break;
3794                 }
3795
3796                 err = sel_netnode_sid(addrp, family, &sid);
3797                 if (err)
3798                         goto out;
3799
3800                 AVC_AUDIT_DATA_INIT(&ad, NET);
3801                 ad.u.net.sport = htons(snum);
3802                 ad.u.net.family = family;
3803
3804                 if (family == PF_INET)
3805                         ad.u.net.v4info.saddr = addr4->sin_addr.s_addr;
3806                 else
3807                         ipv6_addr_copy(&ad.u.net.v6info.saddr, &addr6->sin6_addr);
3808
3809                 err = avc_has_perm(isec->sid, sid,
3810                                    isec->sclass, node_perm, &ad);
3811                 if (err)
3812                         goto out;
3813         }
3814 out:
3815         return err;
3816 }
3817
3818 static int selinux_socket_connect(struct socket *sock, struct sockaddr *address, int addrlen)
3819 {
3820         struct sock *sk = sock->sk;
3821         struct inode_security_struct *isec;
3822         int err;
3823
3824         err = socket_has_perm(current, sock, SOCKET__CONNECT);
3825         if (err)
3826                 return err;
3827
3828         /*
3829          * If a TCP or DCCP socket, check name_connect permission for the port.
3830          */
3831         isec = SOCK_INODE(sock)->i_security;
3832         if (isec->sclass == SECCLASS_TCP_SOCKET ||
3833             isec->sclass == SECCLASS_DCCP_SOCKET) {
3834                 struct avc_audit_data ad;
3835                 struct sockaddr_in *addr4 = NULL;
3836                 struct sockaddr_in6 *addr6 = NULL;
3837                 unsigned short snum;
3838                 u32 sid, perm;
3839
3840                 if (sk->sk_family == PF_INET) {
3841                         addr4 = (struct sockaddr_in *)address;
3842                         if (addrlen < sizeof(struct sockaddr_in))
3843                                 return -EINVAL;
3844                         snum = ntohs(addr4->sin_port);
3845                 } else {
3846                         addr6 = (struct sockaddr_in6 *)address;
3847                         if (addrlen < SIN6_LEN_RFC2133)
3848                                 return -EINVAL;
3849                         snum = ntohs(addr6->sin6_port);
3850                 }
3851
3852                 err = sel_netport_sid(sk->sk_protocol, snum, &sid);
3853                 if (err)
3854                         goto out;
3855
3856                 perm = (isec->sclass == SECCLASS_TCP_SOCKET) ?
3857                        TCP_SOCKET__NAME_CONNECT : DCCP_SOCKET__NAME_CONNECT;
3858
3859                 AVC_AUDIT_DATA_INIT(&ad, NET);
3860                 ad.u.net.dport = htons(snum);
3861                 ad.u.net.family = sk->sk_family;
3862                 err = avc_has_perm(isec->sid, sid, isec->sclass, perm, &ad);
3863                 if (err)
3864                         goto out;
3865         }
3866
3867         err = selinux_netlbl_socket_connect(sk, address);
3868
3869 out:
3870         return err;
3871 }
3872
3873 static int selinux_socket_listen(struct socket *sock, int backlog)
3874 {
3875         return socket_has_perm(current, sock, SOCKET__LISTEN);
3876 }
3877
3878 static int selinux_socket_accept(struct socket *sock, struct socket *newsock)
3879 {
3880         int err;
3881         struct inode_security_struct *isec;
3882         struct inode_security_struct *newisec;
3883
3884         err = socket_has_perm(current, sock, SOCKET__ACCEPT);
3885         if (err)
3886                 return err;
3887
3888         newisec = SOCK_INODE(newsock)->i_security;
3889
3890         isec = SOCK_INODE(sock)->i_security;
3891         newisec->sclass = isec->sclass;
3892         newisec->sid = isec->sid;
3893         newisec->initialized = 1;
3894
3895         return 0;
3896 }
3897
3898 static int selinux_socket_sendmsg(struct socket *sock, struct msghdr *msg,
3899                                   int size)
3900 {
3901         return socket_has_perm(current, sock, SOCKET__WRITE);
3902 }
3903
3904 static int selinux_socket_recvmsg(struct socket *sock, struct msghdr *msg,
3905                                   int size, int flags)
3906 {
3907         return socket_has_perm(current, sock, SOCKET__READ);
3908 }
3909
3910 static int selinux_socket_getsockname(struct socket *sock)
3911 {
3912         return socket_has_perm(current, sock, SOCKET__GETATTR);
3913 }
3914
3915 static int selinux_socket_getpeername(struct socket *sock)
3916 {
3917         return socket_has_perm(current, sock, SOCKET__GETATTR);
3918 }
3919
3920 static int selinux_socket_setsockopt(struct socket *sock, int level, int optname)
3921 {
3922         int err;
3923
3924         err = socket_has_perm(current, sock, SOCKET__SETOPT);
3925         if (err)
3926                 return err;
3927
3928         return selinux_netlbl_socket_setsockopt(sock, level, optname);
3929 }
3930
3931 static int selinux_socket_getsockopt(struct socket *sock, int level,
3932                                      int optname)
3933 {
3934         return socket_has_perm(current, sock, SOCKET__GETOPT);
3935 }
3936
3937 static int selinux_socket_shutdown(struct socket *sock, int how)
3938 {
3939         return socket_has_perm(current, sock, SOCKET__SHUTDOWN);
3940 }
3941
3942 static int selinux_socket_unix_stream_connect(struct socket *sock,
3943                                               struct socket *other,
3944                                               struct sock *newsk)
3945 {
3946         struct sk_security_struct *ssec;
3947         struct inode_security_struct *isec;
3948         struct inode_security_struct *other_isec;
3949         struct avc_audit_data ad;
3950         int err;
3951
3952         isec = SOCK_INODE(sock)->i_security;
3953         other_isec = SOCK_INODE(other)->i_security;
3954
3955         AVC_AUDIT_DATA_INIT(&ad, NET);
3956         ad.u.net.sk = other->sk;
3957
3958         err = avc_has_perm(isec->sid, other_isec->sid,
3959                            isec->sclass,
3960                            UNIX_STREAM_SOCKET__CONNECTTO, &ad);
3961         if (err)
3962                 return err;
3963
3964         /* connecting socket */
3965         ssec = sock->sk->sk_security;
3966         ssec->peer_sid = other_isec->sid;
3967
3968         /* server child socket */
3969         ssec = newsk->sk_security;
3970         ssec->peer_sid = isec->sid;
3971         err = security_sid_mls_copy(other_isec->sid, ssec->peer_sid, &ssec->sid);
3972
3973         return err;
3974 }
3975
3976 static int selinux_socket_unix_may_send(struct socket *sock,
3977                                         struct socket *other)
3978 {
3979         struct inode_security_struct *isec;
3980         struct inode_security_struct *other_isec;
3981         struct avc_audit_data ad;
3982         int err;
3983
3984         isec = SOCK_INODE(sock)->i_security;
3985         other_isec = SOCK_INODE(other)->i_security;
3986
3987         AVC_AUDIT_DATA_INIT(&ad, NET);
3988         ad.u.net.sk = other->sk;
3989
3990         err = avc_has_perm(isec->sid, other_isec->sid,
3991                            isec->sclass, SOCKET__SENDTO, &ad);
3992         if (err)
3993                 return err;
3994
3995         return 0;
3996 }
3997
3998 static int selinux_inet_sys_rcv_skb(int ifindex, char *addrp, u16 family,
3999                                     u32 peer_sid,
4000                                     struct avc_audit_data *ad)
4001 {
4002         int err;
4003         u32 if_sid;
4004         u32 node_sid;
4005
4006         err = sel_netif_sid(ifindex, &if_sid);
4007         if (err)
4008                 return err;
4009         err = avc_has_perm(peer_sid, if_sid,
4010                            SECCLASS_NETIF, NETIF__INGRESS, ad);
4011         if (err)
4012                 return err;
4013
4014         err = sel_netnode_sid(addrp, family, &node_sid);
4015         if (err)
4016                 return err;
4017         return avc_has_perm(peer_sid, node_sid,
4018                             SECCLASS_NODE, NODE__RECVFROM, ad);
4019 }
4020
4021 static int selinux_sock_rcv_skb_compat(struct sock *sk, struct sk_buff *skb,
4022                                        u16 family)
4023 {
4024         int err = 0;
4025         struct sk_security_struct *sksec = sk->sk_security;
4026         u32 peer_sid;
4027         u32 sk_sid = sksec->sid;
4028         struct avc_audit_data ad;
4029         char *addrp;
4030
4031         AVC_AUDIT_DATA_INIT(&ad, NET);
4032         ad.u.net.netif = skb->iif;
4033         ad.u.net.family = family;
4034         err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL);
4035         if (err)
4036                 return err;
4037
4038         if (selinux_secmark_enabled()) {
4039                 err = avc_has_perm(sk_sid, skb->secmark, SECCLASS_PACKET,
4040                                    PACKET__RECV, &ad);
4041                 if (err)
4042                         return err;
4043         }
4044
4045         if (selinux_policycap_netpeer) {
4046                 err = selinux_skb_peerlbl_sid(skb, family, &peer_sid);
4047                 if (err)
4048                         return err;
4049                 err = avc_has_perm(sk_sid, peer_sid,
4050                                    SECCLASS_PEER, PEER__RECV, &ad);
4051                 if (err)
4052                         selinux_netlbl_err(skb, err, 0);
4053         } else {
4054                 err = selinux_netlbl_sock_rcv_skb(sksec, skb, family, &ad);
4055                 if (err)
4056                         return err;
4057                 err = selinux_xfrm_sock_rcv_skb(sksec->sid, skb, &ad);
4058         }
4059
4060         return err;
4061 }
4062
4063 static int selinux_socket_sock_rcv_skb(struct sock *sk, struct sk_buff *skb)
4064 {
4065         int err;
4066         struct sk_security_struct *sksec = sk->sk_security;
4067         u16 family = sk->sk_family;
4068         u32 sk_sid = sksec->sid;
4069         struct avc_audit_data ad;
4070         char *addrp;
4071         u8 secmark_active;
4072         u8 peerlbl_active;
4073
4074         if (family != PF_INET && family != PF_INET6)
4075                 return 0;
4076
4077         /* Handle mapped IPv4 packets arriving via IPv6 sockets */
4078         if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
4079                 family = PF_INET;
4080
4081         /* If any sort of compatibility mode is enabled then handoff processing
4082          * to the selinux_sock_rcv_skb_compat() function to deal with the
4083          * special handling.  We do this in an attempt to keep this function
4084          * as fast and as clean as possible. */
4085         if (!selinux_policycap_netpeer)
4086                 return selinux_sock_rcv_skb_compat(sk, skb, family);
4087
4088         secmark_active = selinux_secmark_enabled();
4089         peerlbl_active = netlbl_enabled() || selinux_xfrm_enabled();
4090         if (!secmark_active && !peerlbl_active)
4091                 return 0;
4092
4093         AVC_AUDIT_DATA_INIT(&ad, NET);
4094         ad.u.net.netif = skb->iif;
4095         ad.u.net.family = family;
4096         err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL);
4097         if (err)
4098                 return err;
4099
4100         if (peerlbl_active) {
4101                 u32 peer_sid;
4102
4103                 err = selinux_skb_peerlbl_sid(skb, family, &peer_sid);
4104                 if (err)
4105                         return err;
4106                 err = selinux_inet_sys_rcv_skb(skb->iif, addrp, family,
4107                                                peer_sid, &ad);
4108                 if (err) {
4109                         selinux_netlbl_err(skb, err, 0);
4110                         return err;
4111                 }
4112                 err = avc_has_perm(sk_sid, peer_sid, SECCLASS_PEER,
4113                                    PEER__RECV, &ad);
4114                 if (err)
4115                         selinux_netlbl_err(skb, err, 0);
4116         }
4117
4118         if (secmark_active) {
4119                 err = avc_has_perm(sk_sid, skb->secmark, SECCLASS_PACKET,
4120                                    PACKET__RECV, &ad);
4121                 if (err)
4122                         return err;
4123         }
4124
4125         return err;
4126 }
4127
4128 static int selinux_socket_getpeersec_stream(struct socket *sock, char __user *optval,
4129                                             int __user *optlen, unsigned len)
4130 {
4131         int err = 0;
4132         char *scontext;
4133         u32 scontext_len;
4134         struct sk_security_struct *ssec;
4135         struct inode_security_struct *isec;
4136         u32 peer_sid = SECSID_NULL;
4137
4138         isec = SOCK_INODE(sock)->i_security;
4139
4140         if (isec->sclass == SECCLASS_UNIX_STREAM_SOCKET ||
4141             isec->sclass == SECCLASS_TCP_SOCKET) {
4142                 ssec = sock->sk->sk_security;
4143                 peer_sid = ssec->peer_sid;
4144         }
4145         if (peer_sid == SECSID_NULL) {
4146                 err = -ENOPROTOOPT;
4147                 goto out;
4148         }
4149
4150         err = security_sid_to_context(peer_sid, &scontext, &scontext_len);
4151
4152         if (err)
4153                 goto out;
4154
4155         if (scontext_len > len) {
4156                 err = -ERANGE;
4157                 goto out_len;
4158         }
4159
4160         if (copy_to_user(optval, scontext, scontext_len))
4161                 err = -EFAULT;
4162
4163 out_len:
4164         if (put_user(scontext_len, optlen))
4165                 err = -EFAULT;
4166
4167         kfree(scontext);
4168 out:
4169         return err;
4170 }
4171
4172 static int selinux_socket_getpeersec_dgram(struct socket *sock, struct sk_buff *skb, u32 *secid)
4173 {
4174         u32 peer_secid = SECSID_NULL;
4175         u16 family;
4176
4177         if (skb && skb->protocol == htons(ETH_P_IP))
4178                 family = PF_INET;
4179         else if (skb && skb->protocol == htons(ETH_P_IPV6))
4180                 family = PF_INET6;
4181         else if (sock)
4182                 family = sock->sk->sk_family;
4183         else
4184                 goto out;
4185
4186         if (sock && family == PF_UNIX)
4187                 selinux_inode_getsecid(SOCK_INODE(sock), &peer_secid);
4188         else if (skb)
4189                 selinux_skb_peerlbl_sid(skb, family, &peer_secid);
4190
4191 out:
4192         *secid = peer_secid;
4193         if (peer_secid == SECSID_NULL)
4194                 return -EINVAL;
4195         return 0;
4196 }
4197
4198 static int selinux_sk_alloc_security(struct sock *sk, int family, gfp_t priority)
4199 {
4200         return sk_alloc_security(sk, family, priority);
4201 }
4202
4203 static void selinux_sk_free_security(struct sock *sk)
4204 {
4205         sk_free_security(sk);
4206 }
4207
4208 static void selinux_sk_clone_security(const struct sock *sk, struct sock *newsk)
4209 {
4210         struct sk_security_struct *ssec = sk->sk_security;
4211         struct sk_security_struct *newssec = newsk->sk_security;
4212
4213         newssec->sid = ssec->sid;
4214         newssec->peer_sid = ssec->peer_sid;
4215         newssec->sclass = ssec->sclass;
4216
4217         selinux_netlbl_sk_security_reset(newssec);
4218 }
4219
4220 static void selinux_sk_getsecid(struct sock *sk, u32 *secid)
4221 {
4222         if (!sk)
4223                 *secid = SECINITSID_ANY_SOCKET;
4224         else {
4225                 struct sk_security_struct *sksec = sk->sk_security;
4226
4227                 *secid = sksec->sid;
4228         }
4229 }
4230
4231 static void selinux_sock_graft(struct sock *sk, struct socket *parent)
4232 {
4233         struct inode_security_struct *isec = SOCK_INODE(parent)->i_security;
4234         struct sk_security_struct *sksec = sk->sk_security;
4235
4236         if (sk->sk_family == PF_INET || sk->sk_family == PF_INET6 ||
4237             sk->sk_family == PF_UNIX)
4238                 isec->sid = sksec->sid;
4239         sksec->sclass = isec->sclass;
4240 }
4241
4242 static int selinux_inet_conn_request(struct sock *sk, struct sk_buff *skb,
4243                                      struct request_sock *req)
4244 {
4245         struct sk_security_struct *sksec = sk->sk_security;
4246         int err;
4247         u16 family = sk->sk_family;
4248         u32 newsid;
4249         u32 peersid;
4250
4251         /* handle mapped IPv4 packets arriving via IPv6 sockets */
4252         if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
4253                 family = PF_INET;
4254
4255         err = selinux_skb_peerlbl_sid(skb, family, &peersid);
4256         if (err)
4257                 return err;
4258         if (peersid == SECSID_NULL) {
4259                 req->secid = sksec->sid;
4260                 req->peer_secid = SECSID_NULL;
4261         } else {
4262                 err = security_sid_mls_copy(sksec->sid, peersid, &newsid);
4263                 if (err)
4264                         return err;
4265                 req->secid = newsid;
4266                 req->peer_secid = peersid;
4267         }
4268
4269         return selinux_netlbl_inet_conn_request(req, family);
4270 }
4271
4272 static void selinux_inet_csk_clone(struct sock *newsk,
4273                                    const struct request_sock *req)
4274 {
4275         struct sk_security_struct *newsksec = newsk->sk_security;
4276
4277         newsksec->sid = req->secid;
4278         newsksec->peer_sid = req->peer_secid;
4279         /* NOTE: Ideally, we should also get the isec->sid for the
4280            new socket in sync, but we don't have the isec available yet.
4281            So we will wait until sock_graft to do it, by which
4282            time it will have been created and available. */
4283
4284         /* We don't need to take any sort of lock here as we are the only
4285          * thread with access to newsksec */
4286         selinux_netlbl_inet_csk_clone(newsk, req->rsk_ops->family);
4287 }
4288
4289 static void selinux_inet_conn_established(struct sock *sk, struct sk_buff *skb)
4290 {
4291         u16 family = sk->sk_family;
4292         struct sk_security_struct *sksec = sk->sk_security;
4293
4294         /* handle mapped IPv4 packets arriving via IPv6 sockets */
4295         if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
4296                 family = PF_INET;
4297
4298         selinux_skb_peerlbl_sid(skb, family, &sksec->peer_sid);
4299 }
4300
4301 static void selinux_req_classify_flow(const struct request_sock *req,
4302                                       struct flowi *fl)
4303 {
4304         fl->secid = req->secid;
4305 }
4306
4307 static int selinux_nlmsg_perm(struct sock *sk, struct sk_buff *skb)
4308 {
4309         int err = 0;
4310         u32 perm;
4311         struct nlmsghdr *nlh;
4312         struct socket *sock = sk->sk_socket;
4313         struct inode_security_struct *isec = SOCK_INODE(sock)->i_security;
4314
4315         if (skb->len < NLMSG_SPACE(0)) {
4316                 err = -EINVAL;
4317                 goto out;
4318         }
4319         nlh = nlmsg_hdr(skb);
4320
4321         err = selinux_nlmsg_lookup(isec->sclass, nlh->nlmsg_type, &perm);
4322         if (err) {
4323                 if (err == -EINVAL) {
4324                         audit_log(current->audit_context, GFP_KERNEL, AUDIT_SELINUX_ERR,
4325                                   "SELinux:  unrecognized netlink message"
4326                                   " type=%hu for sclass=%hu\n",
4327                                   nlh->nlmsg_type, isec->sclass);
4328                         if (!selinux_enforcing || security_get_allow_unknown())
4329                                 err = 0;
4330                 }
4331
4332                 /* Ignore */
4333                 if (err == -ENOENT)
4334                         err = 0;
4335                 goto out;
4336         }
4337
4338         err = socket_has_perm(current, sock, perm);
4339 out:
4340         return err;
4341 }
4342
4343 #ifdef CONFIG_NETFILTER
4344
4345 static unsigned int selinux_ip_forward(struct sk_buff *skb, int ifindex,
4346                                        u16 family)
4347 {
4348         int err;
4349         char *addrp;
4350         u32 peer_sid;
4351         struct avc_audit_data ad;
4352         u8 secmark_active;
4353         u8 netlbl_active;
4354         u8 peerlbl_active;
4355
4356         if (!selinux_policycap_netpeer)
4357                 return NF_ACCEPT;
4358
4359         secmark_active = selinux_secmark_enabled();
4360         netlbl_active = netlbl_enabled();
4361         peerlbl_active = netlbl_active || selinux_xfrm_enabled();
4362         if (!secmark_active && !peerlbl_active)
4363                 return NF_ACCEPT;
4364
4365         if (selinux_skb_peerlbl_sid(skb, family, &peer_sid) != 0)
4366                 return NF_DROP;
4367
4368         AVC_AUDIT_DATA_INIT(&ad, NET);
4369         ad.u.net.netif = ifindex;
4370         ad.u.net.family = family;
4371         if (selinux_parse_skb(skb, &ad, &addrp, 1, NULL) != 0)
4372                 return NF_DROP;
4373
4374         if (peerlbl_active) {
4375                 err = selinux_inet_sys_rcv_skb(ifindex, addrp, family,
4376                                                peer_sid, &ad);
4377                 if (err) {
4378                         selinux_netlbl_err(skb, err, 1);
4379                         return NF_DROP;
4380                 }
4381         }
4382
4383         if (secmark_active)
4384                 if (avc_has_perm(peer_sid, skb->secmark,
4385                                  SECCLASS_PACKET, PACKET__FORWARD_IN, &ad))
4386                         return NF_DROP;
4387
4388         if (netlbl_active)
4389                 /* we do this in the FORWARD path and not the POST_ROUTING
4390                  * path because we want to make sure we apply the necessary
4391                  * labeling before IPsec is applied so we can leverage AH
4392                  * protection */
4393                 if (selinux_netlbl_skbuff_setsid(skb, family, peer_sid) != 0)
4394                         return NF_DROP;
4395
4396         return NF_ACCEPT;
4397 }
4398
4399 static unsigned int selinux_ipv4_forward(unsigned int hooknum,
4400                                          struct sk_buff *skb,
4401                                          const struct net_device *in,
4402                                          const struct net_device *out,
4403                                          int (*okfn)(struct sk_buff *))
4404 {
4405         return selinux_ip_forward(skb, in->ifindex, PF_INET);
4406 }
4407
4408 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
4409 static unsigned int selinux_ipv6_forward(unsigned int hooknum,
4410                                          struct sk_buff *skb,
4411                                          const struct net_device *in,
4412                                          const struct net_device *out,
4413                                          int (*okfn)(struct sk_buff *))
4414 {
4415         return selinux_ip_forward(skb, in->ifindex, PF_INET6);
4416 }
4417 #endif  /* IPV6 */
4418
4419 static unsigned int selinux_ip_output(struct sk_buff *skb,
4420                                       u16 family)
4421 {
4422         u32 sid;
4423
4424         if (!netlbl_enabled())
4425                 return NF_ACCEPT;
4426
4427         /* we do this in the LOCAL_OUT path and not the POST_ROUTING path
4428          * because we want to make sure we apply the necessary labeling
4429          * before IPsec is applied so we can leverage AH protection */
4430         if (skb->sk) {
4431                 struct sk_security_struct *sksec = skb->sk->sk_security;
4432                 sid = sksec->sid;
4433         } else
4434                 sid = SECINITSID_KERNEL;
4435         if (selinux_netlbl_skbuff_setsid(skb, family, sid) != 0)
4436                 return NF_DROP;
4437
4438         return NF_ACCEPT;
4439 }
4440
4441 static unsigned int selinux_ipv4_output(unsigned int hooknum,
4442                                         struct sk_buff *skb,
4443                                         const struct net_device *in,
4444                                         const struct net_device *out,
4445                                         int (*okfn)(struct sk_buff *))
4446 {
4447         return selinux_ip_output(skb, PF_INET);
4448 }
4449
4450 static unsigned int selinux_ip_postroute_compat(struct sk_buff *skb,
4451                                                 int ifindex,
4452                                                 u16 family)
4453 {
4454         struct sock *sk = skb->sk;
4455         struct sk_security_struct *sksec;
4456         struct avc_audit_data ad;
4457         char *addrp;
4458         u8 proto;
4459
4460         if (sk == NULL)
4461                 return NF_ACCEPT;
4462         sksec = sk->sk_security;
4463
4464         AVC_AUDIT_DATA_INIT(&ad, NET);
4465         ad.u.net.netif = ifindex;
4466         ad.u.net.family = family;
4467         if (selinux_parse_skb(skb, &ad, &addrp, 0, &proto))
4468                 return NF_DROP;
4469
4470         if (selinux_secmark_enabled())
4471                 if (avc_has_perm(sksec->sid, skb->secmark,
4472                                  SECCLASS_PACKET, PACKET__SEND, &ad))
4473                         return NF_DROP;
4474
4475         if (selinux_policycap_netpeer)
4476                 if (selinux_xfrm_postroute_last(sksec->sid, skb, &ad, proto))
4477                         return NF_DROP;
4478
4479         return NF_ACCEPT;
4480 }
4481
4482 static unsigned int selinux_ip_postroute(struct sk_buff *skb, int ifindex,
4483                                          u16 family)
4484 {
4485         u32 secmark_perm;
4486         u32 peer_sid;
4487         struct sock *sk;
4488         struct avc_audit_data ad;
4489         char *addrp;
4490         u8 secmark_active;
4491         u8 peerlbl_active;
4492
4493         /* If any sort of compatibility mode is enabled then handoff processing
4494          * to the selinux_ip_postroute_compat() function to deal with the
4495          * special handling.  We do this in an attempt to keep this function
4496          * as fast and as clean as possible. */
4497         if (!selinux_policycap_netpeer)
4498                 return selinux_ip_postroute_compat(skb, ifindex, family);
4499 #ifdef CONFIG_XFRM
4500         /* If skb->dst->xfrm is non-NULL then the packet is undergoing an IPsec
4501          * packet transformation so allow the packet to pass without any checks
4502          * since we'll have another chance to perform access control checks
4503          * when the packet is on it's final way out.
4504          * NOTE: there appear to be some IPv6 multicast cases where skb->dst
4505          *       is NULL, in this case go ahead and apply access control. */
4506         if (skb->dst != NULL && skb->dst->xfrm != NULL)
4507                 return NF_ACCEPT;
4508 #endif
4509         secmark_active = selinux_secmark_enabled();
4510         peerlbl_active = netlbl_enabled() || selinux_xfrm_enabled();
4511         if (!secmark_active && !peerlbl_active)
4512                 return NF_ACCEPT;
4513
4514         /* if the packet is being forwarded then get the peer label from the
4515          * packet itself; otherwise check to see if it is from a local
4516          * application or the kernel, if from an application get the peer label
4517          * from the sending socket, otherwise use the kernel's sid */
4518         sk = skb->sk;
4519         if (sk == NULL) {
4520                 switch (family) {
4521                 case PF_INET:
4522                         if (IPCB(skb)->flags & IPSKB_FORWARDED)
4523                                 secmark_perm = PACKET__FORWARD_OUT;
4524                         else
4525                                 secmark_perm = PACKET__SEND;
4526                         break;
4527                 case PF_INET6:
4528                         if (IP6CB(skb)->flags & IP6SKB_FORWARDED)
4529                                 secmark_perm = PACKET__FORWARD_OUT;
4530                         else
4531                                 secmark_perm = PACKET__SEND;
4532                         break;
4533                 default:
4534                         return NF_DROP;
4535                 }
4536                 if (secmark_perm == PACKET__FORWARD_OUT) {
4537                         if (selinux_skb_peerlbl_sid(skb, family, &peer_sid))
4538                                 return NF_DROP;
4539                 } else
4540                         peer_sid = SECINITSID_KERNEL;
4541         } else {
4542                 struct sk_security_struct *sksec = sk->sk_security;
4543                 peer_sid = sksec->sid;
4544                 secmark_perm = PACKET__SEND;
4545         }
4546
4547         AVC_AUDIT_DATA_INIT(&ad, NET);
4548         ad.u.net.netif = ifindex;
4549         ad.u.net.family = family;
4550         if (selinux_parse_skb(skb, &ad, &addrp, 0, NULL))
4551                 return NF_DROP;
4552
4553         if (secmark_active)
4554                 if (avc_has_perm(peer_sid, skb->secmark,
4555                                  SECCLASS_PACKET, secmark_perm, &ad))
4556                         return NF_DROP;
4557
4558         if (peerlbl_active) {
4559                 u32 if_sid;
4560                 u32 node_sid;
4561
4562                 if (sel_netif_sid(ifindex, &if_sid))
4563                         return NF_DROP;
4564                 if (avc_has_perm(peer_sid, if_sid,
4565                                  SECCLASS_NETIF, NETIF__EGRESS, &ad))
4566                         return NF_DROP;
4567
4568                 if (sel_netnode_sid(addrp, family, &node_sid))
4569                         return NF_DROP;
4570                 if (avc_has_perm(peer_sid, node_sid,
4571                                  SECCLASS_NODE, NODE__SENDTO, &ad))
4572                         return NF_DROP;
4573         }
4574
4575         return NF_ACCEPT;
4576 }
4577
4578 static unsigned int selinux_ipv4_postroute(unsigned int hooknum,
4579                                            struct sk_buff *skb,
4580                                            const struct net_device *in,
4581                                            const struct net_device *out,
4582                                            int (*okfn)(struct sk_buff *))
4583 {
4584         return selinux_ip_postroute(skb, out->ifindex, PF_INET);
4585 }
4586
4587 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
4588 static unsigned int selinux_ipv6_postroute(unsigned int hooknum,
4589                                            struct sk_buff *skb,
4590                                            const struct net_device *in,
4591                                            const struct net_device *out,
4592                                            int (*okfn)(struct sk_buff *))
4593 {
4594         return selinux_ip_postroute(skb, out->ifindex, PF_INET6);
4595 }
4596 #endif  /* IPV6 */
4597
4598 #endif  /* CONFIG_NETFILTER */
4599
4600 static int selinux_netlink_send(struct sock *sk, struct sk_buff *skb)
4601 {
4602         int err;
4603
4604         err = cap_netlink_send(sk, skb);
4605         if (err)
4606                 return err;
4607
4608         if (policydb_loaded_version >= POLICYDB_VERSION_NLCLASS)
4609                 err = selinux_nlmsg_perm(sk, skb);
4610
4611         return err;
4612 }
4613
4614 static int selinux_netlink_recv(struct sk_buff *skb, int capability)
4615 {
4616         int err;
4617         struct avc_audit_data ad;
4618
4619         err = cap_netlink_recv(skb, capability);
4620         if (err)
4621                 return err;
4622
4623         AVC_AUDIT_DATA_INIT(&ad, CAP);
4624         ad.u.cap = capability;
4625
4626         return avc_has_perm(NETLINK_CB(skb).sid, NETLINK_CB(skb).sid,
4627                             SECCLASS_CAPABILITY, CAP_TO_MASK(capability), &ad);
4628 }
4629
4630 static int ipc_alloc_security(struct task_struct *task,
4631                               struct kern_ipc_perm *perm,
4632                               u16 sclass)
4633 {
4634         struct ipc_security_struct *isec;
4635         u32 sid;
4636
4637         isec = kzalloc(sizeof(struct ipc_security_struct), GFP_KERNEL);
4638         if (!isec)
4639                 return -ENOMEM;
4640
4641         sid = task_sid(task);
4642         isec->sclass = sclass;
4643         isec->sid = sid;
4644         perm->security = isec;
4645
4646         return 0;
4647 }
4648
4649 static void ipc_free_security(struct kern_ipc_perm *perm)
4650 {
4651         struct ipc_security_struct *isec = perm->security;
4652         perm->security = NULL;
4653         kfree(isec);
4654 }
4655
4656 static int msg_msg_alloc_security(struct msg_msg *msg)
4657 {
4658         struct msg_security_struct *msec;
4659
4660         msec = kzalloc(sizeof(struct msg_security_struct), GFP_KERNEL);
4661         if (!msec)
4662                 return -ENOMEM;
4663
4664         msec->sid = SECINITSID_UNLABELED;
4665         msg->security = msec;
4666
4667         return 0;
4668 }
4669
4670 static void msg_msg_free_security(struct msg_msg *msg)
4671 {
4672         struct msg_security_struct *msec = msg->security;
4673
4674         msg->security = NULL;
4675         kfree(msec);
4676 }
4677
4678 static int ipc_has_perm(struct kern_ipc_perm *ipc_perms,
4679                         u32 perms)
4680 {
4681         struct ipc_security_struct *isec;
4682         struct avc_audit_data ad;
4683         u32 sid = current_sid();
4684
4685         isec = ipc_perms->security;
4686
4687         AVC_AUDIT_DATA_INIT(&ad, IPC);
4688         ad.u.ipc_id = ipc_perms->key;
4689
4690         return avc_has_perm(sid, isec->sid, isec->sclass, perms, &ad);
4691 }
4692
4693 static int selinux_msg_msg_alloc_security(struct msg_msg *msg)
4694 {
4695         return msg_msg_alloc_security(msg);
4696 }
4697
4698 static void selinux_msg_msg_free_security(struct msg_msg *msg)
4699 {
4700         msg_msg_free_security(msg);
4701 }
4702
4703 /* message queue security operations */
4704 static int selinux_msg_queue_alloc_security(struct msg_queue *msq)
4705 {
4706         struct ipc_security_struct *isec;
4707         struct avc_audit_data ad;
4708         u32 sid = current_sid();
4709         int rc;
4710
4711         rc = ipc_alloc_security(current, &msq->q_perm, SECCLASS_MSGQ);
4712         if (rc)
4713                 return rc;
4714
4715         isec = msq->q_perm.security;
4716
4717         AVC_AUDIT_DATA_INIT(&ad, IPC);
4718         ad.u.ipc_id = msq->q_perm.key;
4719
4720         rc = avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
4721                           MSGQ__CREATE, &ad);
4722         if (rc) {
4723                 ipc_free_security(&msq->q_perm);
4724                 return rc;
4725         }
4726         return 0;
4727 }
4728
4729 static void selinux_msg_queue_free_security(struct msg_queue *msq)
4730 {
4731         ipc_free_security(&msq->q_perm);
4732 }
4733
4734 static int selinux_msg_queue_associate(struct msg_queue *msq, int msqflg)
4735 {
4736         struct ipc_security_struct *isec;
4737         struct avc_audit_data ad;
4738         u32 sid = current_sid();
4739
4740         isec = msq->q_perm.security;
4741
4742         AVC_AUDIT_DATA_INIT(&ad, IPC);
4743         ad.u.ipc_id = msq->q_perm.key;
4744
4745         return avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
4746                             MSGQ__ASSOCIATE, &ad);
4747 }
4748
4749 static int selinux_msg_queue_msgctl(struct msg_queue *msq, int cmd)
4750 {
4751         int err;
4752         int perms;
4753
4754         switch (cmd) {
4755         case IPC_INFO:
4756         case MSG_INFO:
4757                 /* No specific object, just general system-wide information. */
4758                 return task_has_system(current, SYSTEM__IPC_INFO);
4759         case IPC_STAT:
4760         case MSG_STAT:
4761                 perms = MSGQ__GETATTR | MSGQ__ASSOCIATE;
4762                 break;
4763         case IPC_SET:
4764                 perms = MSGQ__SETATTR;
4765                 break;
4766         case IPC_RMID:
4767                 perms = MSGQ__DESTROY;
4768                 break;
4769         default:
4770                 return 0;
4771         }
4772
4773         err = ipc_has_perm(&msq->q_perm, perms);
4774         return err;
4775 }
4776
4777 static int selinux_msg_queue_msgsnd(struct msg_queue *msq, struct msg_msg *msg, int msqflg)
4778 {
4779         struct ipc_security_struct *isec;
4780         struct msg_security_struct *msec;
4781         struct avc_audit_data ad;
4782         u32 sid = current_sid();
4783         int rc;
4784
4785         isec = msq->q_perm.security;
4786         msec = msg->security;
4787
4788         /*
4789          * First time through, need to assign label to the message
4790          */
4791         if (msec->sid == SECINITSID_UNLABELED) {
4792                 /*
4793                  * Compute new sid based on current process and
4794                  * message queue this message will be stored in
4795                  */
4796                 rc = security_transition_sid(sid, isec->sid, SECCLASS_MSG,
4797                                              &msec->sid);
4798                 if (rc)
4799                         return rc;
4800         }
4801
4802         AVC_AUDIT_DATA_INIT(&ad, IPC);
4803         ad.u.ipc_id = msq->q_perm.key;
4804
4805         /* Can this process write to the queue? */
4806         rc = avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
4807                           MSGQ__WRITE, &ad);
4808         if (!rc)
4809                 /* Can this process send the message */
4810                 rc = avc_has_perm(sid, msec->sid, SECCLASS_MSG,
4811                                   MSG__SEND, &ad);
4812         if (!rc)
4813                 /* Can the message be put in the queue? */
4814                 rc = avc_has_perm(msec->sid, isec->sid, SECCLASS_MSGQ,
4815                                   MSGQ__ENQUEUE, &ad);
4816
4817         return rc;
4818 }
4819
4820 static int selinux_msg_queue_msgrcv(struct msg_queue *msq, struct msg_msg *msg,
4821                                     struct task_struct *target,
4822                                     long type, int mode)
4823 {
4824         struct ipc_security_struct *isec;
4825         struct msg_security_struct *msec;
4826         struct avc_audit_data ad;
4827         u32 sid = task_sid(target);
4828         int rc;
4829
4830         isec = msq->q_perm.security;
4831         msec = msg->security;
4832
4833         AVC_AUDIT_DATA_INIT(&ad, IPC);
4834         ad.u.ipc_id = msq->q_perm.key;
4835
4836         rc = avc_has_perm(sid, isec->sid,
4837                           SECCLASS_MSGQ, MSGQ__READ, &ad);
4838         if (!rc)
4839                 rc = avc_has_perm(sid, msec->sid,
4840                                   SECCLASS_MSG, MSG__RECEIVE, &ad);
4841         return rc;
4842 }
4843
4844 /* Shared Memory security operations */
4845 static int selinux_shm_alloc_security(struct shmid_kernel *shp)
4846 {
4847         struct ipc_security_struct *isec;
4848         struct avc_audit_data ad;
4849         u32 sid = current_sid();
4850         int rc;
4851
4852         rc = ipc_alloc_security(current, &shp->shm_perm, SECCLASS_SHM);
4853         if (rc)
4854                 return rc;
4855
4856         isec = shp->shm_perm.security;
4857
4858         AVC_AUDIT_DATA_INIT(&ad, IPC);
4859         ad.u.ipc_id = shp->shm_perm.key;
4860
4861         rc = avc_has_perm(sid, isec->sid, SECCLASS_SHM,
4862                           SHM__CREATE, &ad);
4863         if (rc) {
4864                 ipc_free_security(&shp->shm_perm);
4865                 return rc;
4866         }
4867         return 0;
4868 }
4869
4870 static void selinux_shm_free_security(struct shmid_kernel *shp)
4871 {
4872         ipc_free_security(&shp->shm_perm);
4873 }
4874
4875 static int selinux_shm_associate(struct shmid_kernel *shp, int shmflg)
4876 {
4877         struct ipc_security_struct *isec;
4878         struct avc_audit_data ad;
4879         u32 sid = current_sid();
4880
4881         isec = shp->shm_perm.security;
4882
4883         AVC_AUDIT_DATA_INIT(&ad, IPC);
4884         ad.u.ipc_id = shp->shm_perm.key;
4885
4886         return avc_has_perm(sid, isec->sid, SECCLASS_SHM,
4887                             SHM__ASSOCIATE, &ad);
4888 }
4889
4890 /* Note, at this point, shp is locked down */
4891 static int selinux_shm_shmctl(struct shmid_kernel *shp, int cmd)
4892 {
4893         int perms;
4894         int err;
4895
4896         switch (cmd) {
4897         case IPC_INFO:
4898         case SHM_INFO:
4899                 /* No specific object, just general system-wide information. */
4900                 return task_has_system(current, SYSTEM__IPC_INFO);
4901         case IPC_STAT:
4902         case SHM_STAT:
4903                 perms = SHM__GETATTR | SHM__ASSOCIATE;
4904                 break;
4905         case IPC_SET:
4906                 perms = SHM__SETATTR;
4907                 break;
4908         case SHM_LOCK:
4909         case SHM_UNLOCK:
4910                 perms = SHM__LOCK;
4911                 break;
4912         case IPC_RMID:
4913                 perms = SHM__DESTROY;
4914                 break;
4915         default:
4916                 return 0;
4917         }
4918
4919         err = ipc_has_perm(&shp->shm_perm, perms);
4920         return err;
4921 }
4922
4923 static int selinux_shm_shmat(struct shmid_kernel *shp,
4924                              char __user *shmaddr, int shmflg)
4925 {
4926         u32 perms;
4927
4928         if (shmflg & SHM_RDONLY)
4929                 perms = SHM__READ;
4930         else
4931                 perms = SHM__READ | SHM__WRITE;
4932
4933         return ipc_has_perm(&shp->shm_perm, perms);
4934 }
4935
4936 /* Semaphore security operations */
4937 static int selinux_sem_alloc_security(struct sem_array *sma)
4938 {
4939         struct ipc_security_struct *isec;
4940         struct avc_audit_data ad;
4941         u32 sid = current_sid();
4942         int rc;
4943
4944         rc = ipc_alloc_security(current, &sma->sem_perm, SECCLASS_SEM);
4945         if (rc)
4946                 return rc;
4947
4948         isec = sma->sem_perm.security;
4949
4950         AVC_AUDIT_DATA_INIT(&ad, IPC);
4951         ad.u.ipc_id = sma->sem_perm.key;
4952
4953         rc = avc_has_perm(sid, isec->sid, SECCLASS_SEM,
4954                           SEM__CREATE, &ad);
4955         if (rc) {
4956                 ipc_free_security(&sma->sem_perm);
4957                 return rc;
4958         }
4959         return 0;
4960 }
4961
4962 static void selinux_sem_free_security(struct sem_array *sma)
4963 {
4964         ipc_free_security(&sma->sem_perm);
4965 }
4966
4967 static int selinux_sem_associate(struct sem_array *sma, int semflg)
4968 {
4969         struct ipc_security_struct *isec;
4970         struct avc_audit_data ad;
4971         u32 sid = current_sid();
4972
4973         isec = sma->sem_perm.security;
4974
4975         AVC_AUDIT_DATA_INIT(&ad, IPC);
4976         ad.u.ipc_id = sma->sem_perm.key;
4977
4978         return avc_has_perm(sid, isec->sid, SECCLASS_SEM,
4979                             SEM__ASSOCIATE, &ad);
4980 }
4981
4982 /* Note, at this point, sma is locked down */
4983 static int selinux_sem_semctl(struct sem_array *sma, int cmd)
4984 {
4985         int err;
4986         u32 perms;
4987
4988         switch (cmd) {
4989         case IPC_INFO:
4990         case SEM_INFO:
4991                 /* No specific object, just general system-wide information. */
4992                 return task_has_system(current, SYSTEM__IPC_INFO);
4993         case GETPID:
4994         case GETNCNT:
4995         case GETZCNT:
4996                 perms = SEM__GETATTR;
4997                 break;
4998         case GETVAL:
4999         case GETALL:
5000                 perms = SEM__READ;
5001                 break;
5002         case SETVAL:
5003         case SETALL:
5004                 perms = SEM__WRITE;
5005                 break;
5006         case IPC_RMID:
5007                 perms = SEM__DESTROY;
5008                 break;
5009         case IPC_SET:
5010                 perms = SEM__SETATTR;
5011                 break;
5012         case IPC_STAT:
5013         case SEM_STAT:
5014                 perms = SEM__GETATTR | SEM__ASSOCIATE;
5015                 break;
5016         default:
5017                 return 0;
5018         }
5019
5020         err = ipc_has_perm(&sma->sem_perm, perms);
5021         return err;
5022 }
5023
5024 static int selinux_sem_semop(struct sem_array *sma,
5025                              struct sembuf *sops, unsigned nsops, int alter)
5026 {
5027         u32 perms;
5028
5029         if (alter)
5030                 perms = SEM__READ | SEM__WRITE;
5031         else
5032                 perms = SEM__READ;
5033
5034         return ipc_has_perm(&sma->sem_perm, perms);
5035 }
5036
5037 static int selinux_ipc_permission(struct kern_ipc_perm *ipcp, short flag)
5038 {
5039         u32 av = 0;
5040
5041         av = 0;
5042         if (flag & S_IRUGO)
5043                 av |= IPC__UNIX_READ;
5044         if (flag & S_IWUGO)
5045                 av |= IPC__UNIX_WRITE;
5046
5047         if (av == 0)
5048                 return 0;
5049
5050         return ipc_has_perm(ipcp, av);
5051 }
5052
5053 static void selinux_ipc_getsecid(struct kern_ipc_perm *ipcp, u32 *secid)
5054 {
5055         struct ipc_security_struct *isec = ipcp->security;
5056         *secid = isec->sid;
5057 }
5058
5059 static void selinux_d_instantiate(struct dentry *dentry, struct inode *inode)
5060 {
5061         if (inode)
5062                 inode_doinit_with_dentry(inode, dentry);
5063 }
5064
5065 static int selinux_getprocattr(struct task_struct *p,
5066                                char *name, char **value)
5067 {
5068         const struct task_security_struct *__tsec;
5069         u32 sid;
5070         int error;
5071         unsigned len;
5072
5073         if (current != p) {
5074                 error = current_has_perm(p, PROCESS__GETATTR);
5075                 if (error)
5076                         return error;
5077         }
5078
5079         rcu_read_lock();
5080         __tsec = __task_cred(p)->security;
5081
5082         if (!strcmp(name, "current"))
5083                 sid = __tsec->sid;
5084         else if (!strcmp(name, "prev"))
5085                 sid = __tsec->osid;
5086         else if (!strcmp(name, "exec"))
5087                 sid = __tsec->exec_sid;
5088         else if (!strcmp(name, "fscreate"))
5089                 sid = __tsec->create_sid;
5090         else if (!strcmp(name, "keycreate"))
5091                 sid = __tsec->keycreate_sid;
5092         else if (!strcmp(name, "sockcreate"))
5093                 sid = __tsec->sockcreate_sid;
5094         else
5095                 goto invalid;
5096         rcu_read_unlock();
5097
5098         if (!sid)
5099                 return 0;
5100
5101         error = security_sid_to_context(sid, value, &len);
5102         if (error)
5103                 return error;
5104         return len;
5105
5106 invalid:
5107         rcu_read_unlock();
5108         return -EINVAL;
5109 }
5110
5111 static int selinux_setprocattr(struct task_struct *p,
5112                                char *name, void *value, size_t size)
5113 {
5114         struct task_security_struct *tsec;
5115         struct task_struct *tracer;
5116         struct cred *new;
5117         u32 sid = 0, ptsid;
5118         int error;
5119         char *str = value;
5120
5121         if (current != p) {
5122                 /* SELinux only allows a process to change its own
5123                    security attributes. */
5124                 return -EACCES;
5125         }
5126
5127         /*
5128          * Basic control over ability to set these attributes at all.
5129          * current == p, but we'll pass them separately in case the
5130          * above restriction is ever removed.
5131          */
5132         if (!strcmp(name, "exec"))
5133                 error = current_has_perm(p, PROCESS__SETEXEC);
5134         else if (!strcmp(name, "fscreate"))
5135                 error = current_has_perm(p, PROCESS__SETFSCREATE);
5136         else if (!strcmp(name, "keycreate"))
5137                 error = current_has_perm(p, PROCESS__SETKEYCREATE);
5138         else if (!strcmp(name, "sockcreate"))
5139                 error = current_has_perm(p, PROCESS__SETSOCKCREATE);
5140         else if (!strcmp(name, "current"))
5141                 error = current_has_perm(p, PROCESS__SETCURRENT);
5142         else
5143                 error = -EINVAL;
5144         if (error)
5145                 return error;
5146
5147         /* Obtain a SID for the context, if one was specified. */
5148         if (size && str[1] && str[1] != '\n') {
5149                 if (str[size-1] == '\n') {
5150                         str[size-1] = 0;
5151                         size--;
5152                 }
5153                 error = security_context_to_sid(value, size, &sid);
5154                 if (error == -EINVAL && !strcmp(name, "fscreate")) {
5155                         if (!capable(CAP_MAC_ADMIN))
5156                                 return error;
5157                         error = security_context_to_sid_force(value, size,
5158                                                               &sid);
5159                 }
5160                 if (error)
5161                         return error;
5162         }
5163
5164         new = prepare_creds();
5165         if (!new)
5166                 return -ENOMEM;
5167
5168         /* Permission checking based on the specified context is
5169            performed during the actual operation (execve,
5170            open/mkdir/...), when we know the full context of the
5171            operation.  See selinux_bprm_set_creds for the execve
5172            checks and may_create for the file creation checks. The
5173            operation will then fail if the context is not permitted. */
5174         tsec = new->security;
5175         if (!strcmp(name, "exec")) {
5176                 tsec->exec_sid = sid;
5177         } else if (!strcmp(name, "fscreate")) {
5178                 tsec->create_sid = sid;
5179         } else if (!strcmp(name, "keycreate")) {
5180                 error = may_create_key(sid, p);
5181                 if (error)
5182                         goto abort_change;
5183                 tsec->keycreate_sid = sid;
5184         } else if (!strcmp(name, "sockcreate")) {
5185                 tsec->sockcreate_sid = sid;
5186         } else if (!strcmp(name, "current")) {
5187                 error = -EINVAL;
5188                 if (sid == 0)
5189                         goto abort_change;
5190
5191                 /* Only allow single threaded processes to change context */
5192                 error = -EPERM;
5193                 if (!is_single_threaded(p)) {
5194                         error = security_bounded_transition(tsec->sid, sid);
5195                         if (error)
5196                                 goto abort_change;
5197                 }
5198
5199                 /* Check permissions for the transition. */
5200                 error = avc_has_perm(tsec->sid, sid, SECCLASS_PROCESS,
5201                                      PROCESS__DYNTRANSITION, NULL);
5202                 if (error)
5203                         goto abort_change;
5204
5205                 /* Check for ptracing, and update the task SID if ok.
5206                    Otherwise, leave SID unchanged and fail. */
5207                 ptsid = 0;
5208                 task_lock(p);
5209                 tracer = tracehook_tracer_task(p);
5210                 if (tracer)
5211                         ptsid = task_sid(tracer);
5212                 task_unlock(p);
5213
5214                 if (tracer) {
5215                         error = avc_has_perm(ptsid, sid, SECCLASS_PROCESS,
5216                                              PROCESS__PTRACE, NULL);
5217                         if (error)
5218                                 goto abort_change;
5219                 }
5220
5221                 tsec->sid = sid;
5222         } else {
5223                 error = -EINVAL;
5224                 goto abort_change;
5225         }
5226
5227         commit_creds(new);
5228         return size;
5229
5230 abort_change:
5231         abort_creds(new);
5232         return error;
5233 }
5234
5235 static int selinux_secid_to_secctx(u32 secid, char **secdata, u32 *seclen)
5236 {
5237         return security_sid_to_context(secid, secdata, seclen);
5238 }
5239
5240 static int selinux_secctx_to_secid(const char *secdata, u32 seclen, u32 *secid)
5241 {
5242         return security_context_to_sid(secdata, seclen, secid);
5243 }
5244
5245 static void selinux_release_secctx(char *secdata, u32 seclen)
5246 {
5247         kfree(secdata);
5248 }
5249
5250 #ifdef CONFIG_KEYS
5251
5252 static int selinux_key_alloc(struct key *k, const struct cred *cred,
5253                              unsigned long flags)
5254 {
5255         const struct task_security_struct *tsec;
5256         struct key_security_struct *ksec;
5257
5258         ksec = kzalloc(sizeof(struct key_security_struct), GFP_KERNEL);
5259         if (!ksec)
5260                 return -ENOMEM;
5261
5262         tsec = cred->security;
5263         if (tsec->keycreate_sid)
5264                 ksec->sid = tsec->keycreate_sid;
5265         else
5266                 ksec->sid = tsec->sid;
5267
5268         k->security = ksec;
5269         return 0;
5270 }
5271
5272 static void selinux_key_free(struct key *k)
5273 {
5274         struct key_security_struct *ksec = k->security;
5275
5276         k->security = NULL;
5277         kfree(ksec);
5278 }
5279
5280 static int selinux_key_permission(key_ref_t key_ref,
5281                                   const struct cred *cred,
5282                                   key_perm_t perm)
5283 {
5284         struct key *key;
5285         struct key_security_struct *ksec;
5286         u32 sid;
5287
5288         /* if no specific permissions are requested, we skip the
5289            permission check. No serious, additional covert channels
5290            appear to be created. */
5291         if (perm == 0)
5292                 return 0;
5293
5294         sid = cred_sid(cred);
5295
5296         key = key_ref_to_ptr(key_ref);
5297         ksec = key->security;
5298
5299         return avc_has_perm(sid, ksec->sid, SECCLASS_KEY, perm, NULL);
5300 }
5301
5302 static int selinux_key_getsecurity(struct key *key, char **_buffer)
5303 {
5304         struct key_security_struct *ksec = key->security;
5305         char *context = NULL;
5306         unsigned len;
5307         int rc;
5308
5309         rc = security_sid_to_context(ksec->sid, &context, &len);
5310         if (!rc)
5311                 rc = len;
5312         *_buffer = context;
5313         return rc;
5314 }
5315
5316 #endif
5317
5318 static struct security_operations selinux_ops = {
5319         .name =                         "selinux",
5320
5321         .ptrace_may_access =            selinux_ptrace_may_access,
5322         .ptrace_traceme =               selinux_ptrace_traceme,
5323         .capget =                       selinux_capget,
5324         .capset =                       selinux_capset,
5325         .sysctl =                       selinux_sysctl,
5326         .capable =                      selinux_capable,
5327         .quotactl =                     selinux_quotactl,
5328         .quota_on =                     selinux_quota_on,
5329         .syslog =                       selinux_syslog,
5330         .vm_enough_memory =             selinux_vm_enough_memory,
5331
5332         .netlink_send =                 selinux_netlink_send,
5333         .netlink_recv =                 selinux_netlink_recv,
5334
5335         .bprm_set_creds =               selinux_bprm_set_creds,
5336         .bprm_committing_creds =        selinux_bprm_committing_creds,
5337         .bprm_committed_creds =         selinux_bprm_committed_creds,
5338         .bprm_secureexec =              selinux_bprm_secureexec,
5339
5340         .sb_alloc_security =            selinux_sb_alloc_security,
5341         .sb_free_security =             selinux_sb_free_security,
5342         .sb_copy_data =                 selinux_sb_copy_data,
5343         .sb_kern_mount =                selinux_sb_kern_mount,
5344         .sb_show_options =              selinux_sb_show_options,
5345         .sb_statfs =                    selinux_sb_statfs,
5346         .sb_mount =                     selinux_mount,
5347         .sb_umount =                    selinux_umount,
5348         .sb_set_mnt_opts =              selinux_set_mnt_opts,
5349         .sb_clone_mnt_opts =            selinux_sb_clone_mnt_opts,
5350         .sb_parse_opts_str =            selinux_parse_opts_str,
5351
5352
5353         .inode_alloc_security =         selinux_inode_alloc_security,
5354         .inode_free_security =          selinux_inode_free_security,
5355         .inode_init_security =          selinux_inode_init_security,
5356         .inode_create =                 selinux_inode_create,
5357         .inode_link =                   selinux_inode_link,
5358         .inode_unlink =                 selinux_inode_unlink,
5359         .inode_symlink =                selinux_inode_symlink,
5360         .inode_mkdir =                  selinux_inode_mkdir,
5361         .inode_rmdir =                  selinux_inode_rmdir,
5362         .inode_mknod =                  selinux_inode_mknod,
5363         .inode_rename =                 selinux_inode_rename,
5364         .inode_readlink =               selinux_inode_readlink,
5365         .inode_follow_link =            selinux_inode_follow_link,
5366         .inode_permission =             selinux_inode_permission,
5367         .inode_setattr =                selinux_inode_setattr,
5368         .inode_getattr =                selinux_inode_getattr,
5369         .inode_setxattr =               selinux_inode_setxattr,
5370         .inode_post_setxattr =          selinux_inode_post_setxattr,
5371         .inode_getxattr =               selinux_inode_getxattr,
5372         .inode_listxattr =              selinux_inode_listxattr,
5373         .inode_removexattr =            selinux_inode_removexattr,
5374         .inode_getsecurity =            selinux_inode_getsecurity,
5375         .inode_setsecurity =            selinux_inode_setsecurity,
5376         .inode_listsecurity =           selinux_inode_listsecurity,
5377         .inode_getsecid =               selinux_inode_getsecid,
5378
5379         .file_permission =              selinux_file_permission,
5380         .file_alloc_security =          selinux_file_alloc_security,
5381         .file_free_security =           selinux_file_free_security,
5382         .file_ioctl =                   selinux_file_ioctl,
5383         .file_mmap =                    selinux_file_mmap,
5384         .file_mprotect =                selinux_file_mprotect,
5385         .file_lock =                    selinux_file_lock,
5386         .file_fcntl =                   selinux_file_fcntl,
5387         .file_set_fowner =              selinux_file_set_fowner,
5388         .file_send_sigiotask =          selinux_file_send_sigiotask,
5389         .file_receive =                 selinux_file_receive,
5390
5391         .dentry_open =                  selinux_dentry_open,
5392
5393         .task_create =                  selinux_task_create,
5394         .cred_free =                    selinux_cred_free,
5395         .cred_prepare =                 selinux_cred_prepare,
5396         .kernel_act_as =                selinux_kernel_act_as,
5397         .kernel_create_files_as =       selinux_kernel_create_files_as,
5398         .task_setpgid =                 selinux_task_setpgid,
5399         .task_getpgid =                 selinux_task_getpgid,
5400         .task_getsid =                  selinux_task_getsid,
5401         .task_getsecid =                selinux_task_getsecid,
5402         .task_setnice =                 selinux_task_setnice,
5403         .task_setioprio =               selinux_task_setioprio,
5404         .task_getioprio =               selinux_task_getioprio,
5405         .task_setrlimit =               selinux_task_setrlimit,
5406         .task_setscheduler =            selinux_task_setscheduler,
5407         .task_getscheduler =            selinux_task_getscheduler,
5408         .task_movememory =              selinux_task_movememory,
5409         .task_kill =                    selinux_task_kill,
5410         .task_wait =                    selinux_task_wait,
5411         .task_to_inode =                selinux_task_to_inode,
5412
5413         .ipc_permission =               selinux_ipc_permission,
5414         .ipc_getsecid =                 selinux_ipc_getsecid,
5415
5416         .msg_msg_alloc_security =       selinux_msg_msg_alloc_security,
5417         .msg_msg_free_security =        selinux_msg_msg_free_security,
5418
5419         .msg_queue_alloc_security =     selinux_msg_queue_alloc_security,
5420         .msg_queue_free_security =      selinux_msg_queue_free_security,
5421         .msg_queue_associate =          selinux_msg_queue_associate,
5422         .msg_queue_msgctl =             selinux_msg_queue_msgctl,
5423         .msg_queue_msgsnd =             selinux_msg_queue_msgsnd,
5424         .msg_queue_msgrcv =             selinux_msg_queue_msgrcv,
5425
5426         .shm_alloc_security =           selinux_shm_alloc_security,
5427         .shm_free_security =            selinux_shm_free_security,
5428         .shm_associate =                selinux_shm_associate,
5429         .shm_shmctl =                   selinux_shm_shmctl,
5430         .shm_shmat =                    selinux_shm_shmat,
5431
5432         .sem_alloc_security =           selinux_sem_alloc_security,
5433         .sem_free_security =            selinux_sem_free_security,
5434         .sem_associate =                selinux_sem_associate,
5435         .sem_semctl =                   selinux_sem_semctl,
5436         .sem_semop =                    selinux_sem_semop,
5437
5438         .d_instantiate =                selinux_d_instantiate,
5439
5440         .getprocattr =                  selinux_getprocattr,
5441         .setprocattr =                  selinux_setprocattr,
5442
5443         .secid_to_secctx =              selinux_secid_to_secctx,
5444         .secctx_to_secid =              selinux_secctx_to_secid,
5445         .release_secctx =               selinux_release_secctx,
5446
5447         .unix_stream_connect =          selinux_socket_unix_stream_connect,
5448         .unix_may_send =                selinux_socket_unix_may_send,
5449
5450         .socket_create =                selinux_socket_create,
5451         .socket_post_create =           selinux_socket_post_create,
5452         .socket_bind =                  selinux_socket_bind,
5453         .socket_connect =               selinux_socket_connect,
5454         .socket_listen =                selinux_socket_listen,
5455         .socket_accept =                selinux_socket_accept,
5456         .socket_sendmsg =               selinux_socket_sendmsg,
5457         .socket_recvmsg =               selinux_socket_recvmsg,
5458         .socket_getsockname =           selinux_socket_getsockname,
5459         .socket_getpeername =           selinux_socket_getpeername,
5460         .socket_getsockopt =            selinux_socket_getsockopt,
5461         .socket_setsockopt =            selinux_socket_setsockopt,
5462         .socket_shutdown =              selinux_socket_shutdown,
5463         .socket_sock_rcv_skb =          selinux_socket_sock_rcv_skb,
5464         .socket_getpeersec_stream =     selinux_socket_getpeersec_stream,
5465         .socket_getpeersec_dgram =      selinux_socket_getpeersec_dgram,
5466         .sk_alloc_security =            selinux_sk_alloc_security,
5467         .sk_free_security =             selinux_sk_free_security,
5468         .sk_clone_security =            selinux_sk_clone_security,
5469         .sk_getsecid =                  selinux_sk_getsecid,
5470         .sock_graft =                   selinux_sock_graft,
5471         .inet_conn_request =            selinux_inet_conn_request,
5472         .inet_csk_clone =               selinux_inet_csk_clone,
5473         .inet_conn_established =        selinux_inet_conn_established,
5474         .req_classify_flow =            selinux_req_classify_flow,
5475
5476 #ifdef CONFIG_SECURITY_NETWORK_XFRM
5477         .xfrm_policy_alloc_security =   selinux_xfrm_policy_alloc,
5478         .xfrm_policy_clone_security =   selinux_xfrm_policy_clone,
5479         .xfrm_policy_free_security =    selinux_xfrm_policy_free,
5480         .xfrm_policy_delete_security =  selinux_xfrm_policy_delete,
5481         .xfrm_state_alloc_security =    selinux_xfrm_state_alloc,
5482         .xfrm_state_free_security =     selinux_xfrm_state_free,
5483         .xfrm_state_delete_security =   selinux_xfrm_state_delete,
5484         .xfrm_policy_lookup =           selinux_xfrm_policy_lookup,
5485         .xfrm_state_pol_flow_match =    selinux_xfrm_state_pol_flow_match,
5486         .xfrm_decode_session =          selinux_xfrm_decode_session,
5487 #endif
5488
5489 #ifdef CONFIG_KEYS
5490         .key_alloc =                    selinux_key_alloc,
5491         .key_free =                     selinux_key_free,
5492         .key_permission =               selinux_key_permission,
5493         .key_getsecurity =              selinux_key_getsecurity,
5494 #endif
5495
5496 #ifdef CONFIG_AUDIT
5497         .audit_rule_init =              selinux_audit_rule_init,
5498         .audit_rule_known =             selinux_audit_rule_known,
5499         .audit_rule_match =             selinux_audit_rule_match,
5500         .audit_rule_free =              selinux_audit_rule_free,
5501 #endif
5502 };
5503
5504 static __init int selinux_init(void)
5505 {
5506         if (!security_module_enable(&selinux_ops)) {
5507                 selinux_enabled = 0;
5508                 return 0;
5509         }
5510
5511         if (!selinux_enabled) {
5512                 printk(KERN_INFO "SELinux:  Disabled at boot.\n");
5513                 return 0;
5514         }
5515
5516         printk(KERN_INFO "SELinux:  Initializing.\n");
5517
5518         /* Set the security state for the initial task. */
5519         cred_init_security();
5520
5521         sel_inode_cache = kmem_cache_create("selinux_inode_security",
5522                                             sizeof(struct inode_security_struct),
5523                                             0, SLAB_PANIC, NULL);
5524         avc_init();
5525
5526         secondary_ops = security_ops;
5527         if (!secondary_ops)
5528                 panic("SELinux: No initial security operations\n");
5529         if (register_security(&selinux_ops))
5530                 panic("SELinux: Unable to register with kernel.\n");
5531
5532         if (selinux_enforcing)
5533                 printk(KERN_DEBUG "SELinux:  Starting in enforcing mode\n");
5534         else
5535                 printk(KERN_DEBUG "SELinux:  Starting in permissive mode\n");
5536
5537         return 0;
5538 }
5539
5540 void selinux_complete_init(void)
5541 {
5542         printk(KERN_DEBUG "SELinux:  Completing initialization.\n");
5543
5544         /* Set up any superblocks initialized prior to the policy load. */
5545         printk(KERN_DEBUG "SELinux:  Setting up existing superblocks.\n");
5546         spin_lock(&sb_lock);
5547         spin_lock(&sb_security_lock);
5548 next_sb:
5549         if (!list_empty(&superblock_security_head)) {
5550                 struct superblock_security_struct *sbsec =
5551                                 list_entry(superblock_security_head.next,
5552                                            struct superblock_security_struct,
5553                                            list);
5554                 struct super_block *sb = sbsec->sb;
5555                 sb->s_count++;
5556                 spin_unlock(&sb_security_lock);
5557                 spin_unlock(&sb_lock);
5558                 down_read(&sb->s_umount);
5559                 if (sb->s_root)
5560                         superblock_doinit(sb, NULL);
5561                 drop_super(sb);
5562                 spin_lock(&sb_lock);
5563                 spin_lock(&sb_security_lock);
5564                 list_del_init(&sbsec->list);
5565                 goto next_sb;
5566         }
5567         spin_unlock(&sb_security_lock);
5568         spin_unlock(&sb_lock);
5569 }
5570
5571 /* SELinux requires early initialization in order to label
5572    all processes and objects when they are created. */
5573 security_initcall(selinux_init);
5574
5575 #if defined(CONFIG_NETFILTER)
5576
5577 static struct nf_hook_ops selinux_ipv4_ops[] = {
5578         {
5579                 .hook =         selinux_ipv4_postroute,
5580                 .owner =        THIS_MODULE,
5581                 .pf =           PF_INET,
5582                 .hooknum =      NF_INET_POST_ROUTING,
5583                 .priority =     NF_IP_PRI_SELINUX_LAST,
5584         },
5585         {
5586                 .hook =         selinux_ipv4_forward,
5587                 .owner =        THIS_MODULE,
5588                 .pf =           PF_INET,
5589                 .hooknum =      NF_INET_FORWARD,
5590                 .priority =     NF_IP_PRI_SELINUX_FIRST,
5591         },
5592         {
5593                 .hook =         selinux_ipv4_output,
5594                 .owner =        THIS_MODULE,
5595                 .pf =           PF_INET,
5596                 .hooknum =      NF_INET_LOCAL_OUT,
5597                 .priority =     NF_IP_PRI_SELINUX_FIRST,
5598         }
5599 };
5600
5601 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
5602
5603 static struct nf_hook_ops selinux_ipv6_ops[] = {
5604         {
5605                 .hook =         selinux_ipv6_postroute,
5606                 .owner =        THIS_MODULE,
5607                 .pf =           PF_INET6,
5608                 .hooknum =      NF_INET_POST_ROUTING,
5609                 .priority =     NF_IP6_PRI_SELINUX_LAST,
5610         },
5611         {
5612                 .hook =         selinux_ipv6_forward,
5613                 .owner =        THIS_MODULE,
5614                 .pf =           PF_INET6,
5615                 .hooknum =      NF_INET_FORWARD,
5616                 .priority =     NF_IP6_PRI_SELINUX_FIRST,
5617         }
5618 };
5619
5620 #endif  /* IPV6 */
5621
5622 static int __init selinux_nf_ip_init(void)
5623 {
5624         int err = 0;
5625
5626         if (!selinux_enabled)
5627                 goto out;
5628
5629         printk(KERN_DEBUG "SELinux:  Registering netfilter hooks\n");
5630
5631         err = nf_register_hooks(selinux_ipv4_ops, ARRAY_SIZE(selinux_ipv4_ops));
5632         if (err)
5633                 panic("SELinux: nf_register_hooks for IPv4: error %d\n", err);
5634
5635 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
5636         err = nf_register_hooks(selinux_ipv6_ops, ARRAY_SIZE(selinux_ipv6_ops));
5637         if (err)
5638                 panic("SELinux: nf_register_hooks for IPv6: error %d\n", err);
5639 #endif  /* IPV6 */
5640
5641 out:
5642         return err;
5643 }
5644
5645 __initcall(selinux_nf_ip_init);
5646
5647 #ifdef CONFIG_SECURITY_SELINUX_DISABLE
5648 static void selinux_nf_ip_exit(void)
5649 {
5650         printk(KERN_DEBUG "SELinux:  Unregistering netfilter hooks\n");
5651
5652         nf_unregister_hooks(selinux_ipv4_ops, ARRAY_SIZE(selinux_ipv4_ops));
5653 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
5654         nf_unregister_hooks(selinux_ipv6_ops, ARRAY_SIZE(selinux_ipv6_ops));
5655 #endif  /* IPV6 */
5656 }
5657 #endif
5658
5659 #else /* CONFIG_NETFILTER */
5660
5661 #ifdef CONFIG_SECURITY_SELINUX_DISABLE
5662 #define selinux_nf_ip_exit()
5663 #endif
5664
5665 #endif /* CONFIG_NETFILTER */
5666
5667 #ifdef CONFIG_SECURITY_SELINUX_DISABLE
5668 static int selinux_disabled;
5669
5670 int selinux_disable(void)
5671 {
5672         extern void exit_sel_fs(void);
5673
5674         if (ss_initialized) {
5675                 /* Not permitted after initial policy load. */
5676                 return -EINVAL;
5677         }
5678
5679         if (selinux_disabled) {
5680                 /* Only do this once. */
5681                 return -EINVAL;
5682         }
5683
5684         printk(KERN_INFO "SELinux:  Disabled at runtime.\n");
5685
5686         selinux_disabled = 1;
5687         selinux_enabled = 0;
5688
5689         /* Reset security_ops to the secondary module, dummy or capability. */
5690         security_ops = secondary_ops;
5691
5692         /* Unregister netfilter hooks. */
5693         selinux_nf_ip_exit();
5694
5695         /* Unregister selinuxfs. */
5696         exit_sel_fs();
5697
5698         return 0;
5699 }
5700 #endif