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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                         kfree(context);
1289
1290                         /* Need a larger buffer.  Query for the right size. */
1291                         rc = inode->i_op->getxattr(dentry, XATTR_NAME_SELINUX,
1292                                                    NULL, 0);
1293                         if (rc < 0) {
1294                                 dput(dentry);
1295                                 goto out_unlock;
1296                         }
1297                         len = rc;
1298                         context = kmalloc(len+1, GFP_NOFS);
1299                         if (!context) {
1300                                 rc = -ENOMEM;
1301                                 dput(dentry);
1302                                 goto out_unlock;
1303                         }
1304                         context[len] = '\0';
1305                         rc = inode->i_op->getxattr(dentry,
1306                                                    XATTR_NAME_SELINUX,
1307                                                    context, len);
1308                 }
1309                 dput(dentry);
1310                 if (rc < 0) {
1311                         if (rc != -ENODATA) {
1312                                 printk(KERN_WARNING "SELinux: %s:  getxattr returned "
1313                                        "%d for dev=%s ino=%ld\n", __func__,
1314                                        -rc, inode->i_sb->s_id, inode->i_ino);
1315                                 kfree(context);
1316                                 goto out_unlock;
1317                         }
1318                         /* Map ENODATA to the default file SID */
1319                         sid = sbsec->def_sid;
1320                         rc = 0;
1321                 } else {
1322                         rc = security_context_to_sid_default(context, rc, &sid,
1323                                                              sbsec->def_sid,
1324                                                              GFP_NOFS);
1325                         if (rc) {
1326                                 char *dev = inode->i_sb->s_id;
1327                                 unsigned long ino = inode->i_ino;
1328
1329                                 if (rc == -EINVAL) {
1330                                         if (printk_ratelimit())
1331                                                 printk(KERN_NOTICE "SELinux: inode=%lu on dev=%s was found to have an invalid "
1332                                                         "context=%s.  This indicates you may need to relabel the inode or the "
1333                                                         "filesystem in question.\n", ino, dev, context);
1334                                 } else {
1335                                         printk(KERN_WARNING "SELinux: %s:  context_to_sid(%s) "
1336                                                "returned %d for dev=%s ino=%ld\n",
1337                                                __func__, context, -rc, dev, ino);
1338                                 }
1339                                 kfree(context);
1340                                 /* Leave with the unlabeled SID */
1341                                 rc = 0;
1342                                 break;
1343                         }
1344                 }
1345                 kfree(context);
1346                 isec->sid = sid;
1347                 break;
1348         case SECURITY_FS_USE_TASK:
1349                 isec->sid = isec->task_sid;
1350                 break;
1351         case SECURITY_FS_USE_TRANS:
1352                 /* Default to the fs SID. */
1353                 isec->sid = sbsec->sid;
1354
1355                 /* Try to obtain a transition SID. */
1356                 isec->sclass = inode_mode_to_security_class(inode->i_mode);
1357                 rc = security_transition_sid(isec->task_sid,
1358                                              sbsec->sid,
1359                                              isec->sclass,
1360                                              &sid);
1361                 if (rc)
1362                         goto out_unlock;
1363                 isec->sid = sid;
1364                 break;
1365         case SECURITY_FS_USE_MNTPOINT:
1366                 isec->sid = sbsec->mntpoint_sid;
1367                 break;
1368         default:
1369                 /* Default to the fs superblock SID. */
1370                 isec->sid = sbsec->sid;
1371
1372                 if ((sbsec->flags & SE_SBPROC) && !S_ISLNK(inode->i_mode)) {
1373                         struct proc_inode *proci = PROC_I(inode);
1374                         if (proci->pde) {
1375                                 isec->sclass = inode_mode_to_security_class(inode->i_mode);
1376                                 rc = selinux_proc_get_sid(proci->pde,
1377                                                           isec->sclass,
1378                                                           &sid);
1379                                 if (rc)
1380                                         goto out_unlock;
1381                                 isec->sid = sid;
1382                         }
1383                 }
1384                 break;
1385         }
1386
1387         isec->initialized = 1;
1388
1389 out_unlock:
1390         mutex_unlock(&isec->lock);
1391 out:
1392         if (isec->sclass == SECCLASS_FILE)
1393                 isec->sclass = inode_mode_to_security_class(inode->i_mode);
1394         return rc;
1395 }
1396
1397 /* Convert a Linux signal to an access vector. */
1398 static inline u32 signal_to_av(int sig)
1399 {
1400         u32 perm = 0;
1401
1402         switch (sig) {
1403         case SIGCHLD:
1404                 /* Commonly granted from child to parent. */
1405                 perm = PROCESS__SIGCHLD;
1406                 break;
1407         case SIGKILL:
1408                 /* Cannot be caught or ignored */
1409                 perm = PROCESS__SIGKILL;
1410                 break;
1411         case SIGSTOP:
1412                 /* Cannot be caught or ignored */
1413                 perm = PROCESS__SIGSTOP;
1414                 break;
1415         default:
1416                 /* All other signals. */
1417                 perm = PROCESS__SIGNAL;
1418                 break;
1419         }
1420
1421         return perm;
1422 }
1423
1424 /*
1425  * Check permission between a pair of credentials
1426  * fork check, ptrace check, etc.
1427  */
1428 static int cred_has_perm(const struct cred *actor,
1429                          const struct cred *target,
1430                          u32 perms)
1431 {
1432         u32 asid = cred_sid(actor), tsid = cred_sid(target);
1433
1434         return avc_has_perm(asid, tsid, SECCLASS_PROCESS, perms, NULL);
1435 }
1436
1437 /*
1438  * Check permission between a pair of tasks, e.g. signal checks,
1439  * fork check, ptrace check, etc.
1440  * tsk1 is the actor and tsk2 is the target
1441  * - this uses the default subjective creds of tsk1
1442  */
1443 static int task_has_perm(const struct task_struct *tsk1,
1444                          const struct task_struct *tsk2,
1445                          u32 perms)
1446 {
1447         const struct task_security_struct *__tsec1, *__tsec2;
1448         u32 sid1, sid2;
1449
1450         rcu_read_lock();
1451         __tsec1 = __task_cred(tsk1)->security;  sid1 = __tsec1->sid;
1452         __tsec2 = __task_cred(tsk2)->security;  sid2 = __tsec2->sid;
1453         rcu_read_unlock();
1454         return avc_has_perm(sid1, sid2, SECCLASS_PROCESS, perms, NULL);
1455 }
1456
1457 /*
1458  * Check permission between current and another task, e.g. signal checks,
1459  * fork check, ptrace check, etc.
1460  * current is the actor and tsk2 is the target
1461  * - this uses current's subjective creds
1462  */
1463 static int current_has_perm(const struct task_struct *tsk,
1464                             u32 perms)
1465 {
1466         u32 sid, tsid;
1467
1468         sid = current_sid();
1469         tsid = task_sid(tsk);
1470         return avc_has_perm(sid, tsid, SECCLASS_PROCESS, perms, NULL);
1471 }
1472
1473 #if CAP_LAST_CAP > 63
1474 #error Fix SELinux to handle capabilities > 63.
1475 #endif
1476
1477 /* Check whether a task is allowed to use a capability. */
1478 static int task_has_capability(struct task_struct *tsk,
1479                                const struct cred *cred,
1480                                int cap, int audit)
1481 {
1482         struct avc_audit_data ad;
1483         struct av_decision avd;
1484         u16 sclass;
1485         u32 sid = cred_sid(cred);
1486         u32 av = CAP_TO_MASK(cap);
1487         int rc;
1488
1489         AVC_AUDIT_DATA_INIT(&ad, CAP);
1490         ad.tsk = tsk;
1491         ad.u.cap = cap;
1492
1493         switch (CAP_TO_INDEX(cap)) {
1494         case 0:
1495                 sclass = SECCLASS_CAPABILITY;
1496                 break;
1497         case 1:
1498                 sclass = SECCLASS_CAPABILITY2;
1499                 break;
1500         default:
1501                 printk(KERN_ERR
1502                        "SELinux:  out of range capability %d\n", cap);
1503                 BUG();
1504         }
1505
1506         rc = avc_has_perm_noaudit(sid, sid, sclass, av, 0, &avd);
1507         if (audit == SECURITY_CAP_AUDIT)
1508                 avc_audit(sid, sid, sclass, av, &avd, rc, &ad);
1509         return rc;
1510 }
1511
1512 /* Check whether a task is allowed to use a system operation. */
1513 static int task_has_system(struct task_struct *tsk,
1514                            u32 perms)
1515 {
1516         u32 sid = task_sid(tsk);
1517
1518         return avc_has_perm(sid, SECINITSID_KERNEL,
1519                             SECCLASS_SYSTEM, perms, NULL);
1520 }
1521
1522 /* Check whether a task has a particular permission to an inode.
1523    The 'adp' parameter is optional and allows other audit
1524    data to be passed (e.g. the dentry). */
1525 static int inode_has_perm(const struct cred *cred,
1526                           struct inode *inode,
1527                           u32 perms,
1528                           struct avc_audit_data *adp)
1529 {
1530         struct inode_security_struct *isec;
1531         struct avc_audit_data ad;
1532         u32 sid;
1533
1534         if (unlikely(IS_PRIVATE(inode)))
1535                 return 0;
1536
1537         sid = cred_sid(cred);
1538         isec = inode->i_security;
1539
1540         if (!adp) {
1541                 adp = &ad;
1542                 AVC_AUDIT_DATA_INIT(&ad, FS);
1543                 ad.u.fs.inode = inode;
1544         }
1545
1546         return avc_has_perm(sid, isec->sid, isec->sclass, perms, adp);
1547 }
1548
1549 /* Same as inode_has_perm, but pass explicit audit data containing
1550    the dentry to help the auditing code to more easily generate the
1551    pathname if needed. */
1552 static inline int dentry_has_perm(const struct cred *cred,
1553                                   struct vfsmount *mnt,
1554                                   struct dentry *dentry,
1555                                   u32 av)
1556 {
1557         struct inode *inode = dentry->d_inode;
1558         struct avc_audit_data ad;
1559
1560         AVC_AUDIT_DATA_INIT(&ad, FS);
1561         ad.u.fs.path.mnt = mnt;
1562         ad.u.fs.path.dentry = dentry;
1563         return inode_has_perm(cred, inode, av, &ad);
1564 }
1565
1566 /* Check whether a task can use an open file descriptor to
1567    access an inode in a given way.  Check access to the
1568    descriptor itself, and then use dentry_has_perm to
1569    check a particular permission to the file.
1570    Access to the descriptor is implicitly granted if it
1571    has the same SID as the process.  If av is zero, then
1572    access to the file is not checked, e.g. for cases
1573    where only the descriptor is affected like seek. */
1574 static int file_has_perm(const struct cred *cred,
1575                          struct file *file,
1576                          u32 av)
1577 {
1578         struct file_security_struct *fsec = file->f_security;
1579         struct inode *inode = file->f_path.dentry->d_inode;
1580         struct avc_audit_data ad;
1581         u32 sid = cred_sid(cred);
1582         int rc;
1583
1584         AVC_AUDIT_DATA_INIT(&ad, FS);
1585         ad.u.fs.path = file->f_path;
1586
1587         if (sid != fsec->sid) {
1588                 rc = avc_has_perm(sid, fsec->sid,
1589                                   SECCLASS_FD,
1590                                   FD__USE,
1591                                   &ad);
1592                 if (rc)
1593                         goto out;
1594         }
1595
1596         /* av is zero if only checking access to the descriptor. */
1597         rc = 0;
1598         if (av)
1599                 rc = inode_has_perm(cred, inode, av, &ad);
1600
1601 out:
1602         return rc;
1603 }
1604
1605 /* Check whether a task can create a file. */
1606 static int may_create(struct inode *dir,
1607                       struct dentry *dentry,
1608                       u16 tclass)
1609 {
1610         const struct cred *cred = current_cred();
1611         const struct task_security_struct *tsec = cred->security;
1612         struct inode_security_struct *dsec;
1613         struct superblock_security_struct *sbsec;
1614         u32 sid, newsid;
1615         struct avc_audit_data ad;
1616         int rc;
1617
1618         dsec = dir->i_security;
1619         sbsec = dir->i_sb->s_security;
1620
1621         sid = tsec->sid;
1622         newsid = tsec->create_sid;
1623
1624         AVC_AUDIT_DATA_INIT(&ad, FS);
1625         ad.u.fs.path.dentry = dentry;
1626
1627         rc = avc_has_perm(sid, dsec->sid, SECCLASS_DIR,
1628                           DIR__ADD_NAME | DIR__SEARCH,
1629                           &ad);
1630         if (rc)
1631                 return rc;
1632
1633         if (!newsid || !(sbsec->flags & SE_SBLABELSUPP)) {
1634                 rc = security_transition_sid(sid, dsec->sid, tclass, &newsid);
1635                 if (rc)
1636                         return rc;
1637         }
1638
1639         rc = avc_has_perm(sid, newsid, tclass, FILE__CREATE, &ad);
1640         if (rc)
1641                 return rc;
1642
1643         return avc_has_perm(newsid, sbsec->sid,
1644                             SECCLASS_FILESYSTEM,
1645                             FILESYSTEM__ASSOCIATE, &ad);
1646 }
1647
1648 /* Check whether a task can create a key. */
1649 static int may_create_key(u32 ksid,
1650                           struct task_struct *ctx)
1651 {
1652         u32 sid = task_sid(ctx);
1653
1654         return avc_has_perm(sid, ksid, SECCLASS_KEY, KEY__CREATE, NULL);
1655 }
1656
1657 #define MAY_LINK        0
1658 #define MAY_UNLINK      1
1659 #define MAY_RMDIR       2
1660
1661 /* Check whether a task can link, unlink, or rmdir a file/directory. */
1662 static int may_link(struct inode *dir,
1663                     struct dentry *dentry,
1664                     int kind)
1665
1666 {
1667         struct inode_security_struct *dsec, *isec;
1668         struct avc_audit_data ad;
1669         u32 sid = current_sid();
1670         u32 av;
1671         int rc;
1672
1673         dsec = dir->i_security;
1674         isec = dentry->d_inode->i_security;
1675
1676         AVC_AUDIT_DATA_INIT(&ad, FS);
1677         ad.u.fs.path.dentry = dentry;
1678
1679         av = DIR__SEARCH;
1680         av |= (kind ? DIR__REMOVE_NAME : DIR__ADD_NAME);
1681         rc = avc_has_perm(sid, dsec->sid, SECCLASS_DIR, av, &ad);
1682         if (rc)
1683                 return rc;
1684
1685         switch (kind) {
1686         case MAY_LINK:
1687                 av = FILE__LINK;
1688                 break;
1689         case MAY_UNLINK:
1690                 av = FILE__UNLINK;
1691                 break;
1692         case MAY_RMDIR:
1693                 av = DIR__RMDIR;
1694                 break;
1695         default:
1696                 printk(KERN_WARNING "SELinux: %s:  unrecognized kind %d\n",
1697                         __func__, kind);
1698                 return 0;
1699         }
1700
1701         rc = avc_has_perm(sid, isec->sid, isec->sclass, av, &ad);
1702         return rc;
1703 }
1704
1705 static inline int may_rename(struct inode *old_dir,
1706                              struct dentry *old_dentry,
1707                              struct inode *new_dir,
1708                              struct dentry *new_dentry)
1709 {
1710         struct inode_security_struct *old_dsec, *new_dsec, *old_isec, *new_isec;
1711         struct avc_audit_data ad;
1712         u32 sid = current_sid();
1713         u32 av;
1714         int old_is_dir, new_is_dir;
1715         int rc;
1716
1717         old_dsec = old_dir->i_security;
1718         old_isec = old_dentry->d_inode->i_security;
1719         old_is_dir = S_ISDIR(old_dentry->d_inode->i_mode);
1720         new_dsec = new_dir->i_security;
1721
1722         AVC_AUDIT_DATA_INIT(&ad, FS);
1723
1724         ad.u.fs.path.dentry = old_dentry;
1725         rc = avc_has_perm(sid, old_dsec->sid, SECCLASS_DIR,
1726                           DIR__REMOVE_NAME | DIR__SEARCH, &ad);
1727         if (rc)
1728                 return rc;
1729         rc = avc_has_perm(sid, old_isec->sid,
1730                           old_isec->sclass, FILE__RENAME, &ad);
1731         if (rc)
1732                 return rc;
1733         if (old_is_dir && new_dir != old_dir) {
1734                 rc = avc_has_perm(sid, old_isec->sid,
1735                                   old_isec->sclass, DIR__REPARENT, &ad);
1736                 if (rc)
1737                         return rc;
1738         }
1739
1740         ad.u.fs.path.dentry = new_dentry;
1741         av = DIR__ADD_NAME | DIR__SEARCH;
1742         if (new_dentry->d_inode)
1743                 av |= DIR__REMOVE_NAME;
1744         rc = avc_has_perm(sid, new_dsec->sid, SECCLASS_DIR, av, &ad);
1745         if (rc)
1746                 return rc;
1747         if (new_dentry->d_inode) {
1748                 new_isec = new_dentry->d_inode->i_security;
1749                 new_is_dir = S_ISDIR(new_dentry->d_inode->i_mode);
1750                 rc = avc_has_perm(sid, new_isec->sid,
1751                                   new_isec->sclass,
1752                                   (new_is_dir ? DIR__RMDIR : FILE__UNLINK), &ad);
1753                 if (rc)
1754                         return rc;
1755         }
1756
1757         return 0;
1758 }
1759
1760 /* Check whether a task can perform a filesystem operation. */
1761 static int superblock_has_perm(const struct cred *cred,
1762                                struct super_block *sb,
1763                                u32 perms,
1764                                struct avc_audit_data *ad)
1765 {
1766         struct superblock_security_struct *sbsec;
1767         u32 sid = cred_sid(cred);
1768
1769         sbsec = sb->s_security;
1770         return avc_has_perm(sid, sbsec->sid, SECCLASS_FILESYSTEM, perms, ad);
1771 }
1772
1773 /* Convert a Linux mode and permission mask to an access vector. */
1774 static inline u32 file_mask_to_av(int mode, int mask)
1775 {
1776         u32 av = 0;
1777
1778         if ((mode & S_IFMT) != S_IFDIR) {
1779                 if (mask & MAY_EXEC)
1780                         av |= FILE__EXECUTE;
1781                 if (mask & MAY_READ)
1782                         av |= FILE__READ;
1783
1784                 if (mask & MAY_APPEND)
1785                         av |= FILE__APPEND;
1786                 else if (mask & MAY_WRITE)
1787                         av |= FILE__WRITE;
1788
1789         } else {
1790                 if (mask & MAY_EXEC)
1791                         av |= DIR__SEARCH;
1792                 if (mask & MAY_WRITE)
1793                         av |= DIR__WRITE;
1794                 if (mask & MAY_READ)
1795                         av |= DIR__READ;
1796         }
1797
1798         return av;
1799 }
1800
1801 /* Convert a Linux file to an access vector. */
1802 static inline u32 file_to_av(struct file *file)
1803 {
1804         u32 av = 0;
1805
1806         if (file->f_mode & FMODE_READ)
1807                 av |= FILE__READ;
1808         if (file->f_mode & FMODE_WRITE) {
1809                 if (file->f_flags & O_APPEND)
1810                         av |= FILE__APPEND;
1811                 else
1812                         av |= FILE__WRITE;
1813         }
1814         if (!av) {
1815                 /*
1816                  * Special file opened with flags 3 for ioctl-only use.
1817                  */
1818                 av = FILE__IOCTL;
1819         }
1820
1821         return av;
1822 }
1823
1824 /*
1825  * Convert a file to an access vector and include the correct open
1826  * open permission.
1827  */
1828 static inline u32 open_file_to_av(struct file *file)
1829 {
1830         u32 av = file_to_av(file);
1831
1832         if (selinux_policycap_openperm) {
1833                 mode_t mode = file->f_path.dentry->d_inode->i_mode;
1834                 /*
1835                  * lnk files and socks do not really have an 'open'
1836                  */
1837                 if (S_ISREG(mode))
1838                         av |= FILE__OPEN;
1839                 else if (S_ISCHR(mode))
1840                         av |= CHR_FILE__OPEN;
1841                 else if (S_ISBLK(mode))
1842                         av |= BLK_FILE__OPEN;
1843                 else if (S_ISFIFO(mode))
1844                         av |= FIFO_FILE__OPEN;
1845                 else if (S_ISDIR(mode))
1846                         av |= DIR__OPEN;
1847                 else if (S_ISSOCK(mode))
1848                         av |= SOCK_FILE__OPEN;
1849                 else
1850                         printk(KERN_ERR "SELinux: WARNING: inside %s with "
1851                                 "unknown mode:%o\n", __func__, mode);
1852         }
1853         return av;
1854 }
1855
1856 /* Hook functions begin here. */
1857
1858 static int selinux_ptrace_may_access(struct task_struct *child,
1859                                      unsigned int mode)
1860 {
1861         int rc;
1862
1863         rc = cap_ptrace_may_access(child, mode);
1864         if (rc)
1865                 return rc;
1866
1867         if (mode == PTRACE_MODE_READ) {
1868                 u32 sid = current_sid();
1869                 u32 csid = task_sid(child);
1870                 return avc_has_perm(sid, csid, SECCLASS_FILE, FILE__READ, NULL);
1871         }
1872
1873         return current_has_perm(child, PROCESS__PTRACE);
1874 }
1875
1876 static int selinux_ptrace_traceme(struct task_struct *parent)
1877 {
1878         int rc;
1879
1880         rc = cap_ptrace_traceme(parent);
1881         if (rc)
1882                 return rc;
1883
1884         return task_has_perm(parent, current, PROCESS__PTRACE);
1885 }
1886
1887 static int selinux_capget(struct task_struct *target, kernel_cap_t *effective,
1888                           kernel_cap_t *inheritable, kernel_cap_t *permitted)
1889 {
1890         int error;
1891
1892         error = current_has_perm(target, PROCESS__GETCAP);
1893         if (error)
1894                 return error;
1895
1896         return cap_capget(target, effective, inheritable, permitted);
1897 }
1898
1899 static int selinux_capset(struct cred *new, const struct cred *old,
1900                           const kernel_cap_t *effective,
1901                           const kernel_cap_t *inheritable,
1902                           const kernel_cap_t *permitted)
1903 {
1904         int error;
1905
1906         error = cap_capset(new, old,
1907                                       effective, inheritable, permitted);
1908         if (error)
1909                 return error;
1910
1911         return cred_has_perm(old, new, PROCESS__SETCAP);
1912 }
1913
1914 /*
1915  * (This comment used to live with the selinux_task_setuid hook,
1916  * which was removed).
1917  *
1918  * Since setuid only affects the current process, and since the SELinux
1919  * controls are not based on the Linux identity attributes, SELinux does not
1920  * need to control this operation.  However, SELinux does control the use of
1921  * the CAP_SETUID and CAP_SETGID capabilities using the capable hook.
1922  */
1923
1924 static int selinux_capable(struct task_struct *tsk, const struct cred *cred,
1925                            int cap, int audit)
1926 {
1927         int rc;
1928
1929         rc = cap_capable(tsk, cred, cap, audit);
1930         if (rc)
1931                 return rc;
1932
1933         return task_has_capability(tsk, cred, cap, audit);
1934 }
1935
1936 static int selinux_sysctl_get_sid(ctl_table *table, u16 tclass, u32 *sid)
1937 {
1938         int buflen, rc;
1939         char *buffer, *path, *end;
1940
1941         rc = -ENOMEM;
1942         buffer = (char *)__get_free_page(GFP_KERNEL);
1943         if (!buffer)
1944                 goto out;
1945
1946         buflen = PAGE_SIZE;
1947         end = buffer+buflen;
1948         *--end = '\0';
1949         buflen--;
1950         path = end-1;
1951         *path = '/';
1952         while (table) {
1953                 const char *name = table->procname;
1954                 size_t namelen = strlen(name);
1955                 buflen -= namelen + 1;
1956                 if (buflen < 0)
1957                         goto out_free;
1958                 end -= namelen;
1959                 memcpy(end, name, namelen);
1960                 *--end = '/';
1961                 path = end;
1962                 table = table->parent;
1963         }
1964         buflen -= 4;
1965         if (buflen < 0)
1966                 goto out_free;
1967         end -= 4;
1968         memcpy(end, "/sys", 4);
1969         path = end;
1970         rc = security_genfs_sid("proc", path, tclass, sid);
1971 out_free:
1972         free_page((unsigned long)buffer);
1973 out:
1974         return rc;
1975 }
1976
1977 static int selinux_sysctl(ctl_table *table, int op)
1978 {
1979         int error = 0;
1980         u32 av;
1981         u32 tsid, sid;
1982         int rc;
1983
1984         sid = current_sid();
1985
1986         rc = selinux_sysctl_get_sid(table, (op == 0001) ?
1987                                     SECCLASS_DIR : SECCLASS_FILE, &tsid);
1988         if (rc) {
1989                 /* Default to the well-defined sysctl SID. */
1990                 tsid = SECINITSID_SYSCTL;
1991         }
1992
1993         /* The op values are "defined" in sysctl.c, thereby creating
1994          * a bad coupling between this module and sysctl.c */
1995         if (op == 001) {
1996                 error = avc_has_perm(sid, tsid,
1997                                      SECCLASS_DIR, DIR__SEARCH, NULL);
1998         } else {
1999                 av = 0;
2000                 if (op & 004)
2001                         av |= FILE__READ;
2002                 if (op & 002)
2003                         av |= FILE__WRITE;
2004                 if (av)
2005                         error = avc_has_perm(sid, tsid,
2006                                              SECCLASS_FILE, av, NULL);
2007         }
2008
2009         return error;
2010 }
2011
2012 static int selinux_quotactl(int cmds, int type, int id, struct super_block *sb)
2013 {
2014         const struct cred *cred = current_cred();
2015         int rc = 0;
2016
2017         if (!sb)
2018                 return 0;
2019
2020         switch (cmds) {
2021         case Q_SYNC:
2022         case Q_QUOTAON:
2023         case Q_QUOTAOFF:
2024         case Q_SETINFO:
2025         case Q_SETQUOTA:
2026                 rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAMOD, NULL);
2027                 break;
2028         case Q_GETFMT:
2029         case Q_GETINFO:
2030         case Q_GETQUOTA:
2031                 rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAGET, NULL);
2032                 break;
2033         default:
2034                 rc = 0;  /* let the kernel handle invalid cmds */
2035                 break;
2036         }
2037         return rc;
2038 }
2039
2040 static int selinux_quota_on(struct dentry *dentry)
2041 {
2042         const struct cred *cred = current_cred();
2043
2044         return dentry_has_perm(cred, NULL, dentry, FILE__QUOTAON);
2045 }
2046
2047 static int selinux_syslog(int type)
2048 {
2049         int rc;
2050
2051         rc = cap_syslog(type);
2052         if (rc)
2053                 return rc;
2054
2055         switch (type) {
2056         case 3:         /* Read last kernel messages */
2057         case 10:        /* Return size of the log buffer */
2058                 rc = task_has_system(current, SYSTEM__SYSLOG_READ);
2059                 break;
2060         case 6:         /* Disable logging to console */
2061         case 7:         /* Enable logging to console */
2062         case 8:         /* Set level of messages printed to console */
2063                 rc = task_has_system(current, SYSTEM__SYSLOG_CONSOLE);
2064                 break;
2065         case 0:         /* Close log */
2066         case 1:         /* Open log */
2067         case 2:         /* Read from log */
2068         case 4:         /* Read/clear last kernel messages */
2069         case 5:         /* Clear ring buffer */
2070         default:
2071                 rc = task_has_system(current, SYSTEM__SYSLOG_MOD);
2072                 break;
2073         }
2074         return rc;
2075 }
2076
2077 /*
2078  * Check that a process has enough memory to allocate a new virtual
2079  * mapping. 0 means there is enough memory for the allocation to
2080  * succeed and -ENOMEM implies there is not.
2081  *
2082  * Do not audit the selinux permission check, as this is applied to all
2083  * processes that allocate mappings.
2084  */
2085 static int selinux_vm_enough_memory(struct mm_struct *mm, long pages)
2086 {
2087         int rc, cap_sys_admin = 0;
2088
2089         rc = selinux_capable(current, current_cred(), CAP_SYS_ADMIN,
2090                              SECURITY_CAP_NOAUDIT);
2091         if (rc == 0)
2092                 cap_sys_admin = 1;
2093
2094         return __vm_enough_memory(mm, pages, cap_sys_admin);
2095 }
2096
2097 /* binprm security operations */
2098
2099 static int selinux_bprm_set_creds(struct linux_binprm *bprm)
2100 {
2101         const struct task_security_struct *old_tsec;
2102         struct task_security_struct *new_tsec;
2103         struct inode_security_struct *isec;
2104         struct avc_audit_data ad;
2105         struct inode *inode = bprm->file->f_path.dentry->d_inode;
2106         int rc;
2107
2108         rc = cap_bprm_set_creds(bprm);
2109         if (rc)
2110                 return rc;
2111
2112         /* SELinux context only depends on initial program or script and not
2113          * the script interpreter */
2114         if (bprm->cred_prepared)
2115                 return 0;
2116
2117         old_tsec = current_security();
2118         new_tsec = bprm->cred->security;
2119         isec = inode->i_security;
2120
2121         /* Default to the current task SID. */
2122         new_tsec->sid = old_tsec->sid;
2123         new_tsec->osid = old_tsec->sid;
2124
2125         /* Reset fs, key, and sock SIDs on execve. */
2126         new_tsec->create_sid = 0;
2127         new_tsec->keycreate_sid = 0;
2128         new_tsec->sockcreate_sid = 0;
2129
2130         if (old_tsec->exec_sid) {
2131                 new_tsec->sid = old_tsec->exec_sid;
2132                 /* Reset exec SID on execve. */
2133                 new_tsec->exec_sid = 0;
2134         } else {
2135                 /* Check for a default transition on this program. */
2136                 rc = security_transition_sid(old_tsec->sid, isec->sid,
2137                                              SECCLASS_PROCESS, &new_tsec->sid);
2138                 if (rc)
2139                         return rc;
2140         }
2141
2142         AVC_AUDIT_DATA_INIT(&ad, FS);
2143         ad.u.fs.path = bprm->file->f_path;
2144
2145         if (bprm->file->f_path.mnt->mnt_flags & MNT_NOSUID)
2146                 new_tsec->sid = old_tsec->sid;
2147
2148         if (new_tsec->sid == old_tsec->sid) {
2149                 rc = avc_has_perm(old_tsec->sid, isec->sid,
2150                                   SECCLASS_FILE, FILE__EXECUTE_NO_TRANS, &ad);
2151                 if (rc)
2152                         return rc;
2153         } else {
2154                 /* Check permissions for the transition. */
2155                 rc = avc_has_perm(old_tsec->sid, new_tsec->sid,
2156                                   SECCLASS_PROCESS, PROCESS__TRANSITION, &ad);
2157                 if (rc)
2158                         return rc;
2159
2160                 rc = avc_has_perm(new_tsec->sid, isec->sid,
2161                                   SECCLASS_FILE, FILE__ENTRYPOINT, &ad);
2162                 if (rc)
2163                         return rc;
2164
2165                 /* Check for shared state */
2166                 if (bprm->unsafe & LSM_UNSAFE_SHARE) {
2167                         rc = avc_has_perm(old_tsec->sid, new_tsec->sid,
2168                                           SECCLASS_PROCESS, PROCESS__SHARE,
2169                                           NULL);
2170                         if (rc)
2171                                 return -EPERM;
2172                 }
2173
2174                 /* Make sure that anyone attempting to ptrace over a task that
2175                  * changes its SID has the appropriate permit */
2176                 if (bprm->unsafe &
2177                     (LSM_UNSAFE_PTRACE | LSM_UNSAFE_PTRACE_CAP)) {
2178                         struct task_struct *tracer;
2179                         struct task_security_struct *sec;
2180                         u32 ptsid = 0;
2181
2182                         rcu_read_lock();
2183                         tracer = tracehook_tracer_task(current);
2184                         if (likely(tracer != NULL)) {
2185                                 sec = __task_cred(tracer)->security;
2186                                 ptsid = sec->sid;
2187                         }
2188                         rcu_read_unlock();
2189
2190                         if (ptsid != 0) {
2191                                 rc = avc_has_perm(ptsid, new_tsec->sid,
2192                                                   SECCLASS_PROCESS,
2193                                                   PROCESS__PTRACE, NULL);
2194                                 if (rc)
2195                                         return -EPERM;
2196                         }
2197                 }
2198
2199                 /* Clear any possibly unsafe personality bits on exec: */
2200                 bprm->per_clear |= PER_CLEAR_ON_SETID;
2201         }
2202
2203         return 0;
2204 }
2205
2206 static int selinux_bprm_secureexec(struct linux_binprm *bprm)
2207 {
2208         const struct cred *cred = current_cred();
2209         const struct task_security_struct *tsec = cred->security;
2210         u32 sid, osid;
2211         int atsecure = 0;
2212
2213         sid = tsec->sid;
2214         osid = tsec->osid;
2215
2216         if (osid != sid) {
2217                 /* Enable secure mode for SIDs transitions unless
2218                    the noatsecure permission is granted between
2219                    the two SIDs, i.e. ahp returns 0. */
2220                 atsecure = avc_has_perm(osid, sid,
2221                                         SECCLASS_PROCESS,
2222                                         PROCESS__NOATSECURE, NULL);
2223         }
2224
2225         return (atsecure || cap_bprm_secureexec(bprm));
2226 }
2227
2228 extern struct vfsmount *selinuxfs_mount;
2229 extern struct dentry *selinux_null;
2230
2231 /* Derived from fs/exec.c:flush_old_files. */
2232 static inline void flush_unauthorized_files(const struct cred *cred,
2233                                             struct files_struct *files)
2234 {
2235         struct avc_audit_data ad;
2236         struct file *file, *devnull = NULL;
2237         struct tty_struct *tty;
2238         struct fdtable *fdt;
2239         long j = -1;
2240         int drop_tty = 0;
2241
2242         tty = get_current_tty();
2243         if (tty) {
2244                 file_list_lock();
2245                 if (!list_empty(&tty->tty_files)) {
2246                         struct inode *inode;
2247
2248                         /* Revalidate access to controlling tty.
2249                            Use inode_has_perm on the tty inode directly rather
2250                            than using file_has_perm, as this particular open
2251                            file may belong to another process and we are only
2252                            interested in the inode-based check here. */
2253                         file = list_first_entry(&tty->tty_files, struct file, f_u.fu_list);
2254                         inode = file->f_path.dentry->d_inode;
2255                         if (inode_has_perm(cred, inode,
2256                                            FILE__READ | FILE__WRITE, NULL)) {
2257                                 drop_tty = 1;
2258                         }
2259                 }
2260                 file_list_unlock();
2261                 tty_kref_put(tty);
2262         }
2263         /* Reset controlling tty. */
2264         if (drop_tty)
2265                 no_tty();
2266
2267         /* Revalidate access to inherited open files. */
2268
2269         AVC_AUDIT_DATA_INIT(&ad, FS);
2270
2271         spin_lock(&files->file_lock);
2272         for (;;) {
2273                 unsigned long set, i;
2274                 int fd;
2275
2276                 j++;
2277                 i = j * __NFDBITS;
2278                 fdt = files_fdtable(files);
2279                 if (i >= fdt->max_fds)
2280                         break;
2281                 set = fdt->open_fds->fds_bits[j];
2282                 if (!set)
2283                         continue;
2284                 spin_unlock(&files->file_lock);
2285                 for ( ; set ; i++, set >>= 1) {
2286                         if (set & 1) {
2287                                 file = fget(i);
2288                                 if (!file)
2289                                         continue;
2290                                 if (file_has_perm(cred,
2291                                                   file,
2292                                                   file_to_av(file))) {
2293                                         sys_close(i);
2294                                         fd = get_unused_fd();
2295                                         if (fd != i) {
2296                                                 if (fd >= 0)
2297                                                         put_unused_fd(fd);
2298                                                 fput(file);
2299                                                 continue;
2300                                         }
2301                                         if (devnull) {
2302                                                 get_file(devnull);
2303                                         } else {
2304                                                 devnull = dentry_open(
2305                                                         dget(selinux_null),
2306                                                         mntget(selinuxfs_mount),
2307                                                         O_RDWR, cred);
2308                                                 if (IS_ERR(devnull)) {
2309                                                         devnull = NULL;
2310                                                         put_unused_fd(fd);
2311                                                         fput(file);
2312                                                         continue;
2313                                                 }
2314                                         }
2315                                         fd_install(fd, devnull);
2316                                 }
2317                                 fput(file);
2318                         }
2319                 }
2320                 spin_lock(&files->file_lock);
2321
2322         }
2323         spin_unlock(&files->file_lock);
2324 }
2325
2326 /*
2327  * Prepare a process for imminent new credential changes due to exec
2328  */
2329 static void selinux_bprm_committing_creds(struct linux_binprm *bprm)
2330 {
2331         struct task_security_struct *new_tsec;
2332         struct rlimit *rlim, *initrlim;
2333         int rc, i;
2334
2335         new_tsec = bprm->cred->security;
2336         if (new_tsec->sid == new_tsec->osid)
2337                 return;
2338
2339         /* Close files for which the new task SID is not authorized. */
2340         flush_unauthorized_files(bprm->cred, current->files);
2341
2342         /* Always clear parent death signal on SID transitions. */
2343         current->pdeath_signal = 0;
2344
2345         /* Check whether the new SID can inherit resource limits from the old
2346          * SID.  If not, reset all soft limits to the lower of the current
2347          * task's hard limit and the init task's soft limit.
2348          *
2349          * Note that the setting of hard limits (even to lower them) can be
2350          * controlled by the setrlimit check.  The inclusion of the init task's
2351          * soft limit into the computation is to avoid resetting soft limits
2352          * higher than the default soft limit for cases where the default is
2353          * lower than the hard limit, e.g. RLIMIT_CORE or RLIMIT_STACK.
2354          */
2355         rc = avc_has_perm(new_tsec->osid, new_tsec->sid, SECCLASS_PROCESS,
2356                           PROCESS__RLIMITINH, NULL);
2357         if (rc) {
2358                 for (i = 0; i < RLIM_NLIMITS; i++) {
2359                         rlim = current->signal->rlim + i;
2360                         initrlim = init_task.signal->rlim + i;
2361                         rlim->rlim_cur = min(rlim->rlim_max, initrlim->rlim_cur);
2362                 }
2363                 update_rlimit_cpu(rlim->rlim_cur);
2364         }
2365 }
2366
2367 /*
2368  * Clean up the process immediately after the installation of new credentials
2369  * due to exec
2370  */
2371 static void selinux_bprm_committed_creds(struct linux_binprm *bprm)
2372 {
2373         const struct task_security_struct *tsec = current_security();
2374         struct itimerval itimer;
2375         u32 osid, sid;
2376         int rc, i;
2377
2378         osid = tsec->osid;
2379         sid = tsec->sid;
2380
2381         if (sid == osid)
2382                 return;
2383
2384         /* Check whether the new SID can inherit signal state from the old SID.
2385          * If not, clear itimers to avoid subsequent signal generation and
2386          * flush and unblock signals.
2387          *
2388          * This must occur _after_ the task SID has been updated so that any
2389          * kill done after the flush will be checked against the new SID.
2390          */
2391         rc = avc_has_perm(osid, sid, SECCLASS_PROCESS, PROCESS__SIGINH, NULL);
2392         if (rc) {
2393                 memset(&itimer, 0, sizeof itimer);
2394                 for (i = 0; i < 3; i++)
2395                         do_setitimer(i, &itimer, NULL);
2396                 spin_lock_irq(&current->sighand->siglock);
2397                 if (!(current->signal->flags & SIGNAL_GROUP_EXIT)) {
2398                         __flush_signals(current);
2399                         flush_signal_handlers(current, 1);
2400                         sigemptyset(&current->blocked);
2401                 }
2402                 spin_unlock_irq(&current->sighand->siglock);
2403         }
2404
2405         /* Wake up the parent if it is waiting so that it can recheck
2406          * wait permission to the new task SID. */
2407         read_lock(&tasklist_lock);
2408         wake_up_interruptible(&current->real_parent->signal->wait_chldexit);
2409         read_unlock(&tasklist_lock);
2410 }
2411
2412 /* superblock security operations */
2413
2414 static int selinux_sb_alloc_security(struct super_block *sb)
2415 {
2416         return superblock_alloc_security(sb);
2417 }
2418
2419 static void selinux_sb_free_security(struct super_block *sb)
2420 {
2421         superblock_free_security(sb);
2422 }
2423
2424 static inline int match_prefix(char *prefix, int plen, char *option, int olen)
2425 {
2426         if (plen > olen)
2427                 return 0;
2428
2429         return !memcmp(prefix, option, plen);
2430 }
2431
2432 static inline int selinux_option(char *option, int len)
2433 {
2434         return (match_prefix(CONTEXT_STR, sizeof(CONTEXT_STR)-1, option, len) ||
2435                 match_prefix(FSCONTEXT_STR, sizeof(FSCONTEXT_STR)-1, option, len) ||
2436                 match_prefix(DEFCONTEXT_STR, sizeof(DEFCONTEXT_STR)-1, option, len) ||
2437                 match_prefix(ROOTCONTEXT_STR, sizeof(ROOTCONTEXT_STR)-1, option, len) ||
2438                 match_prefix(LABELSUPP_STR, sizeof(LABELSUPP_STR)-1, option, len));
2439 }
2440
2441 static inline void take_option(char **to, char *from, int *first, int len)
2442 {
2443         if (!*first) {
2444                 **to = ',';
2445                 *to += 1;
2446         } else
2447                 *first = 0;
2448         memcpy(*to, from, len);
2449         *to += len;
2450 }
2451
2452 static inline void take_selinux_option(char **to, char *from, int *first,
2453                                        int len)
2454 {
2455         int current_size = 0;
2456
2457         if (!*first) {
2458                 **to = '|';
2459                 *to += 1;
2460         } else
2461                 *first = 0;
2462
2463         while (current_size < len) {
2464                 if (*from != '"') {
2465                         **to = *from;
2466                         *to += 1;
2467                 }
2468                 from += 1;
2469                 current_size += 1;
2470         }
2471 }
2472
2473 static int selinux_sb_copy_data(char *orig, char *copy)
2474 {
2475         int fnosec, fsec, rc = 0;
2476         char *in_save, *in_curr, *in_end;
2477         char *sec_curr, *nosec_save, *nosec;
2478         int open_quote = 0;
2479
2480         in_curr = orig;
2481         sec_curr = copy;
2482
2483         nosec = (char *)get_zeroed_page(GFP_KERNEL);
2484         if (!nosec) {
2485                 rc = -ENOMEM;
2486                 goto out;
2487         }
2488
2489         nosec_save = nosec;
2490         fnosec = fsec = 1;
2491         in_save = in_end = orig;
2492
2493         do {
2494                 if (*in_end == '"')
2495                         open_quote = !open_quote;
2496                 if ((*in_end == ',' && open_quote == 0) ||
2497                                 *in_end == '\0') {
2498                         int len = in_end - in_curr;
2499
2500                         if (selinux_option(in_curr, len))
2501                                 take_selinux_option(&sec_curr, in_curr, &fsec, len);
2502                         else
2503                                 take_option(&nosec, in_curr, &fnosec, len);
2504
2505                         in_curr = in_end + 1;
2506                 }
2507         } while (*in_end++);
2508
2509         strcpy(in_save, nosec_save);
2510         free_page((unsigned long)nosec_save);
2511 out:
2512         return rc;
2513 }
2514
2515 static int selinux_sb_kern_mount(struct super_block *sb, int flags, void *data)
2516 {
2517         const struct cred *cred = current_cred();
2518         struct avc_audit_data ad;
2519         int rc;
2520
2521         rc = superblock_doinit(sb, data);
2522         if (rc)
2523                 return rc;
2524
2525         /* Allow all mounts performed by the kernel */
2526         if (flags & MS_KERNMOUNT)
2527                 return 0;
2528
2529         AVC_AUDIT_DATA_INIT(&ad, FS);
2530         ad.u.fs.path.dentry = sb->s_root;
2531         return superblock_has_perm(cred, sb, FILESYSTEM__MOUNT, &ad);
2532 }
2533
2534 static int selinux_sb_statfs(struct dentry *dentry)
2535 {
2536         const struct cred *cred = current_cred();
2537         struct avc_audit_data ad;
2538
2539         AVC_AUDIT_DATA_INIT(&ad, FS);
2540         ad.u.fs.path.dentry = dentry->d_sb->s_root;
2541         return superblock_has_perm(cred, dentry->d_sb, FILESYSTEM__GETATTR, &ad);
2542 }
2543
2544 static int selinux_mount(char *dev_name,
2545                          struct path *path,
2546                          char *type,
2547                          unsigned long flags,
2548                          void *data)
2549 {
2550         const struct cred *cred = current_cred();
2551
2552         if (flags & MS_REMOUNT)
2553                 return superblock_has_perm(cred, path->mnt->mnt_sb,
2554                                            FILESYSTEM__REMOUNT, NULL);
2555         else
2556                 return dentry_has_perm(cred, path->mnt, path->dentry,
2557                                        FILE__MOUNTON);
2558 }
2559
2560 static int selinux_umount(struct vfsmount *mnt, int flags)
2561 {
2562         const struct cred *cred = current_cred();
2563
2564         return superblock_has_perm(cred, mnt->mnt_sb,
2565                                    FILESYSTEM__UNMOUNT, NULL);
2566 }
2567
2568 /* inode security operations */
2569
2570 static int selinux_inode_alloc_security(struct inode *inode)
2571 {
2572         return inode_alloc_security(inode);
2573 }
2574
2575 static void selinux_inode_free_security(struct inode *inode)
2576 {
2577         inode_free_security(inode);
2578 }
2579
2580 static int selinux_inode_init_security(struct inode *inode, struct inode *dir,
2581                                        char **name, void **value,
2582                                        size_t *len)
2583 {
2584         const struct cred *cred = current_cred();
2585         const struct task_security_struct *tsec = cred->security;
2586         struct inode_security_struct *dsec;
2587         struct superblock_security_struct *sbsec;
2588         u32 sid, newsid, clen;
2589         int rc;
2590         char *namep = NULL, *context;
2591
2592         dsec = dir->i_security;
2593         sbsec = dir->i_sb->s_security;
2594
2595         sid = tsec->sid;
2596         newsid = tsec->create_sid;
2597
2598         if (!newsid || !(sbsec->flags & SE_SBLABELSUPP)) {
2599                 rc = security_transition_sid(sid, dsec->sid,
2600                                              inode_mode_to_security_class(inode->i_mode),
2601                                              &newsid);
2602                 if (rc) {
2603                         printk(KERN_WARNING "%s:  "
2604                                "security_transition_sid failed, rc=%d (dev=%s "
2605                                "ino=%ld)\n",
2606                                __func__,
2607                                -rc, inode->i_sb->s_id, inode->i_ino);
2608                         return rc;
2609                 }
2610         }
2611
2612         /* Possibly defer initialization to selinux_complete_init. */
2613         if (sbsec->flags & SE_SBINITIALIZED) {
2614                 struct inode_security_struct *isec = inode->i_security;
2615                 isec->sclass = inode_mode_to_security_class(inode->i_mode);
2616                 isec->sid = newsid;
2617                 isec->initialized = 1;
2618         }
2619
2620         if (!ss_initialized || !(sbsec->flags & SE_SBLABELSUPP))
2621                 return -EOPNOTSUPP;
2622
2623         if (name) {
2624                 namep = kstrdup(XATTR_SELINUX_SUFFIX, GFP_NOFS);
2625                 if (!namep)
2626                         return -ENOMEM;
2627                 *name = namep;
2628         }
2629
2630         if (value && len) {
2631                 rc = security_sid_to_context_force(newsid, &context, &clen);
2632                 if (rc) {
2633                         kfree(namep);
2634                         return rc;
2635                 }
2636                 *value = context;
2637                 *len = clen;
2638         }
2639
2640         return 0;
2641 }
2642
2643 static int selinux_inode_create(struct inode *dir, struct dentry *dentry, int mask)
2644 {
2645         return may_create(dir, dentry, SECCLASS_FILE);
2646 }
2647
2648 static int selinux_inode_link(struct dentry *old_dentry, struct inode *dir, struct dentry *new_dentry)
2649 {
2650         return may_link(dir, old_dentry, MAY_LINK);
2651 }
2652
2653 static int selinux_inode_unlink(struct inode *dir, struct dentry *dentry)
2654 {
2655         return may_link(dir, dentry, MAY_UNLINK);
2656 }
2657
2658 static int selinux_inode_symlink(struct inode *dir, struct dentry *dentry, const char *name)
2659 {
2660         return may_create(dir, dentry, SECCLASS_LNK_FILE);
2661 }
2662
2663 static int selinux_inode_mkdir(struct inode *dir, struct dentry *dentry, int mask)
2664 {
2665         return may_create(dir, dentry, SECCLASS_DIR);
2666 }
2667
2668 static int selinux_inode_rmdir(struct inode *dir, struct dentry *dentry)
2669 {
2670         return may_link(dir, dentry, MAY_RMDIR);
2671 }
2672
2673 static int selinux_inode_mknod(struct inode *dir, struct dentry *dentry, int mode, dev_t dev)
2674 {
2675         return may_create(dir, dentry, inode_mode_to_security_class(mode));
2676 }
2677
2678 static int selinux_inode_rename(struct inode *old_inode, struct dentry *old_dentry,
2679                                 struct inode *new_inode, struct dentry *new_dentry)
2680 {
2681         return may_rename(old_inode, old_dentry, new_inode, new_dentry);
2682 }
2683
2684 static int selinux_inode_readlink(struct dentry *dentry)
2685 {
2686         const struct cred *cred = current_cred();
2687
2688         return dentry_has_perm(cred, NULL, dentry, FILE__READ);
2689 }
2690
2691 static int selinux_inode_follow_link(struct dentry *dentry, struct nameidata *nameidata)
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_permission(struct inode *inode, int mask)
2699 {
2700         const struct cred *cred = current_cred();
2701
2702         if (!mask) {
2703                 /* No permission to check.  Existence test. */
2704                 return 0;
2705         }
2706
2707         return inode_has_perm(cred, inode,
2708                               file_mask_to_av(inode->i_mode, mask), NULL);
2709 }
2710
2711 static int selinux_inode_setattr(struct dentry *dentry, struct iattr *iattr)
2712 {
2713         const struct cred *cred = current_cred();
2714
2715         if (iattr->ia_valid & ATTR_FORCE)
2716                 return 0;
2717
2718         if (iattr->ia_valid & (ATTR_MODE | ATTR_UID | ATTR_GID |
2719                                ATTR_ATIME_SET | ATTR_MTIME_SET))
2720                 return dentry_has_perm(cred, NULL, dentry, FILE__SETATTR);
2721
2722         return dentry_has_perm(cred, NULL, dentry, FILE__WRITE);
2723 }
2724
2725 static int selinux_inode_getattr(struct vfsmount *mnt, struct dentry *dentry)
2726 {
2727         const struct cred *cred = current_cred();
2728
2729         return dentry_has_perm(cred, mnt, dentry, FILE__GETATTR);
2730 }
2731
2732 static int selinux_inode_setotherxattr(struct dentry *dentry, const char *name)
2733 {
2734         const struct cred *cred = current_cred();
2735
2736         if (!strncmp(name, XATTR_SECURITY_PREFIX,
2737                      sizeof XATTR_SECURITY_PREFIX - 1)) {
2738                 if (!strcmp(name, XATTR_NAME_CAPS)) {
2739                         if (!capable(CAP_SETFCAP))
2740                                 return -EPERM;
2741                 } else if (!capable(CAP_SYS_ADMIN)) {
2742                         /* A different attribute in the security namespace.
2743                            Restrict to administrator. */
2744                         return -EPERM;
2745                 }
2746         }
2747
2748         /* Not an attribute we recognize, so just check the
2749            ordinary setattr permission. */
2750         return dentry_has_perm(cred, NULL, dentry, FILE__SETATTR);
2751 }
2752
2753 static int selinux_inode_setxattr(struct dentry *dentry, const char *name,
2754                                   const void *value, size_t size, int flags)
2755 {
2756         struct inode *inode = dentry->d_inode;
2757         struct inode_security_struct *isec = inode->i_security;
2758         struct superblock_security_struct *sbsec;
2759         struct avc_audit_data ad;
2760         u32 newsid, sid = current_sid();
2761         int rc = 0;
2762
2763         if (strcmp(name, XATTR_NAME_SELINUX))
2764                 return selinux_inode_setotherxattr(dentry, name);
2765
2766         sbsec = inode->i_sb->s_security;
2767         if (!(sbsec->flags & SE_SBLABELSUPP))
2768                 return -EOPNOTSUPP;
2769
2770         if (!is_owner_or_cap(inode))
2771                 return -EPERM;
2772
2773         AVC_AUDIT_DATA_INIT(&ad, FS);
2774         ad.u.fs.path.dentry = dentry;
2775
2776         rc = avc_has_perm(sid, isec->sid, isec->sclass,
2777                           FILE__RELABELFROM, &ad);
2778         if (rc)
2779                 return rc;
2780
2781         rc = security_context_to_sid(value, size, &newsid);
2782         if (rc == -EINVAL) {
2783                 if (!capable(CAP_MAC_ADMIN))
2784                         return rc;
2785                 rc = security_context_to_sid_force(value, size, &newsid);
2786         }
2787         if (rc)
2788                 return rc;
2789
2790         rc = avc_has_perm(sid, newsid, isec->sclass,
2791                           FILE__RELABELTO, &ad);
2792         if (rc)
2793                 return rc;
2794
2795         rc = security_validate_transition(isec->sid, newsid, sid,
2796                                           isec->sclass);
2797         if (rc)
2798                 return rc;
2799
2800         return avc_has_perm(newsid,
2801                             sbsec->sid,
2802                             SECCLASS_FILESYSTEM,
2803                             FILESYSTEM__ASSOCIATE,
2804                             &ad);
2805 }
2806
2807 static void selinux_inode_post_setxattr(struct dentry *dentry, const char *name,
2808                                         const void *value, size_t size,
2809                                         int flags)
2810 {
2811         struct inode *inode = dentry->d_inode;
2812         struct inode_security_struct *isec = inode->i_security;
2813         u32 newsid;
2814         int rc;
2815
2816         if (strcmp(name, XATTR_NAME_SELINUX)) {
2817                 /* Not an attribute we recognize, so nothing to do. */
2818                 return;
2819         }
2820
2821         rc = security_context_to_sid_force(value, size, &newsid);
2822         if (rc) {
2823                 printk(KERN_ERR "SELinux:  unable to map context to SID"
2824                        "for (%s, %lu), rc=%d\n",
2825                        inode->i_sb->s_id, inode->i_ino, -rc);
2826                 return;
2827         }
2828
2829         isec->sid = newsid;
2830         return;
2831 }
2832
2833 static int selinux_inode_getxattr(struct dentry *dentry, const char *name)
2834 {
2835         const struct cred *cred = current_cred();
2836
2837         return dentry_has_perm(cred, NULL, dentry, FILE__GETATTR);
2838 }
2839
2840 static int selinux_inode_listxattr(struct dentry *dentry)
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_removexattr(struct dentry *dentry, const char *name)
2848 {
2849         if (strcmp(name, XATTR_NAME_SELINUX))
2850                 return selinux_inode_setotherxattr(dentry, name);
2851
2852         /* No one is allowed to remove a SELinux security label.
2853            You can change the label, but all data must be labeled. */
2854         return -EACCES;
2855 }
2856
2857 /*
2858  * Copy the inode security context value to the user.
2859  *
2860  * Permission check is handled by selinux_inode_getxattr hook.
2861  */
2862 static int selinux_inode_getsecurity(const struct inode *inode, const char *name, void **buffer, bool alloc)
2863 {
2864         u32 size;
2865         int error;
2866         char *context = NULL;
2867         struct inode_security_struct *isec = inode->i_security;
2868
2869         if (strcmp(name, XATTR_SELINUX_SUFFIX))
2870                 return -EOPNOTSUPP;
2871
2872         /*
2873          * If the caller has CAP_MAC_ADMIN, then get the raw context
2874          * value even if it is not defined by current policy; otherwise,
2875          * use the in-core value under current policy.
2876          * Use the non-auditing forms of the permission checks since
2877          * getxattr may be called by unprivileged processes commonly
2878          * and lack of permission just means that we fall back to the
2879          * in-core context value, not a denial.
2880          */
2881         error = selinux_capable(current, current_cred(), CAP_MAC_ADMIN,
2882                                 SECURITY_CAP_NOAUDIT);
2883         if (!error)
2884                 error = security_sid_to_context_force(isec->sid, &context,
2885                                                       &size);
2886         else
2887                 error = security_sid_to_context(isec->sid, &context, &size);
2888         if (error)
2889                 return error;
2890         error = size;
2891         if (alloc) {
2892                 *buffer = context;
2893                 goto out_nofree;
2894         }
2895         kfree(context);
2896 out_nofree:
2897         return error;
2898 }
2899
2900 static int selinux_inode_setsecurity(struct inode *inode, const char *name,
2901                                      const void *value, size_t size, int flags)
2902 {
2903         struct inode_security_struct *isec = inode->i_security;
2904         u32 newsid;
2905         int rc;
2906
2907         if (strcmp(name, XATTR_SELINUX_SUFFIX))
2908                 return -EOPNOTSUPP;
2909
2910         if (!value || !size)
2911                 return -EACCES;
2912
2913         rc = security_context_to_sid((void *)value, size, &newsid);
2914         if (rc)
2915                 return rc;
2916
2917         isec->sid = newsid;
2918         return 0;
2919 }
2920
2921 static int selinux_inode_listsecurity(struct inode *inode, char *buffer, size_t buffer_size)
2922 {
2923         const int len = sizeof(XATTR_NAME_SELINUX);
2924         if (buffer && len <= buffer_size)
2925                 memcpy(buffer, XATTR_NAME_SELINUX, len);
2926         return len;
2927 }
2928
2929 static void selinux_inode_getsecid(const struct inode *inode, u32 *secid)
2930 {
2931         struct inode_security_struct *isec = inode->i_security;
2932         *secid = isec->sid;
2933 }
2934
2935 /* file security operations */
2936
2937 static int selinux_revalidate_file_permission(struct file *file, int mask)
2938 {
2939         const struct cred *cred = current_cred();
2940         struct inode *inode = file->f_path.dentry->d_inode;
2941
2942         if (!mask) {
2943                 /* No permission to check.  Existence test. */
2944                 return 0;
2945         }
2946
2947         /* file_mask_to_av won't add FILE__WRITE if MAY_APPEND is set */
2948         if ((file->f_flags & O_APPEND) && (mask & MAY_WRITE))
2949                 mask |= MAY_APPEND;
2950
2951         return file_has_perm(cred, file,
2952                              file_mask_to_av(inode->i_mode, mask));
2953 }
2954
2955 static int selinux_file_permission(struct file *file, int mask)
2956 {
2957         if (!mask)
2958                 /* No permission to check.  Existence test. */
2959                 return 0;
2960
2961         return selinux_revalidate_file_permission(file, mask);
2962 }
2963
2964 static int selinux_file_alloc_security(struct file *file)
2965 {
2966         return file_alloc_security(file);
2967 }
2968
2969 static void selinux_file_free_security(struct file *file)
2970 {
2971         file_free_security(file);
2972 }
2973
2974 static int selinux_file_ioctl(struct file *file, unsigned int cmd,
2975                               unsigned long arg)
2976 {
2977         const struct cred *cred = current_cred();
2978         u32 av = 0;
2979
2980         if (_IOC_DIR(cmd) & _IOC_WRITE)
2981                 av |= FILE__WRITE;
2982         if (_IOC_DIR(cmd) & _IOC_READ)
2983                 av |= FILE__READ;
2984         if (!av)
2985                 av = FILE__IOCTL;
2986
2987         return file_has_perm(cred, file, av);
2988 }
2989
2990 static int file_map_prot_check(struct file *file, unsigned long prot, int shared)
2991 {
2992         const struct cred *cred = current_cred();
2993         int rc = 0;
2994
2995 #ifndef CONFIG_PPC32
2996         if ((prot & PROT_EXEC) && (!file || (!shared && (prot & PROT_WRITE)))) {
2997                 /*
2998                  * We are making executable an anonymous mapping or a
2999                  * private file mapping that will also be writable.
3000                  * This has an additional check.
3001                  */
3002                 rc = cred_has_perm(cred, cred, PROCESS__EXECMEM);
3003                 if (rc)
3004                         goto error;
3005         }
3006 #endif
3007
3008         if (file) {
3009                 /* read access is always possible with a mapping */
3010                 u32 av = FILE__READ;
3011
3012                 /* write access only matters if the mapping is shared */
3013                 if (shared && (prot & PROT_WRITE))
3014                         av |= FILE__WRITE;
3015
3016                 if (prot & PROT_EXEC)
3017                         av |= FILE__EXECUTE;
3018
3019                 return file_has_perm(cred, file, av);
3020         }
3021
3022 error:
3023         return rc;
3024 }
3025
3026 static int selinux_file_mmap(struct file *file, unsigned long reqprot,
3027                              unsigned long prot, unsigned long flags,
3028                              unsigned long addr, unsigned long addr_only)
3029 {
3030         int rc = 0;
3031         u32 sid = current_sid();
3032
3033         if (addr < mmap_min_addr)
3034                 rc = avc_has_perm(sid, sid, SECCLASS_MEMPROTECT,
3035                                   MEMPROTECT__MMAP_ZERO, NULL);
3036         if (rc || addr_only)
3037                 return rc;
3038
3039         if (selinux_checkreqprot)
3040                 prot = reqprot;
3041
3042         return file_map_prot_check(file, prot,
3043                                    (flags & MAP_TYPE) == MAP_SHARED);
3044 }
3045
3046 static int selinux_file_mprotect(struct vm_area_struct *vma,
3047                                  unsigned long reqprot,
3048                                  unsigned long prot)
3049 {
3050         const struct cred *cred = current_cred();
3051
3052         if (selinux_checkreqprot)
3053                 prot = reqprot;
3054
3055 #ifndef CONFIG_PPC32
3056         if ((prot & PROT_EXEC) && !(vma->vm_flags & VM_EXEC)) {
3057                 int rc = 0;
3058                 if (vma->vm_start >= vma->vm_mm->start_brk &&
3059                     vma->vm_end <= vma->vm_mm->brk) {
3060                         rc = cred_has_perm(cred, cred, PROCESS__EXECHEAP);
3061                 } else if (!vma->vm_file &&
3062                            vma->vm_start <= vma->vm_mm->start_stack &&
3063                            vma->vm_end >= vma->vm_mm->start_stack) {
3064                         rc = current_has_perm(current, PROCESS__EXECSTACK);
3065                 } else if (vma->vm_file && vma->anon_vma) {
3066                         /*
3067                          * We are making executable a file mapping that has
3068                          * had some COW done. Since pages might have been
3069                          * written, check ability to execute the possibly
3070                          * modified content.  This typically should only
3071                          * occur for text relocations.
3072                          */
3073                         rc = file_has_perm(cred, vma->vm_file, FILE__EXECMOD);
3074                 }
3075                 if (rc)
3076                         return rc;
3077         }
3078 #endif
3079
3080         return file_map_prot_check(vma->vm_file, prot, vma->vm_flags&VM_SHARED);
3081 }
3082
3083 static int selinux_file_lock(struct file *file, unsigned int cmd)
3084 {
3085         const struct cred *cred = current_cred();
3086
3087         return file_has_perm(cred, file, FILE__LOCK);
3088 }
3089
3090 static int selinux_file_fcntl(struct file *file, unsigned int cmd,
3091                               unsigned long arg)
3092 {
3093         const struct cred *cred = current_cred();
3094         int err = 0;
3095
3096         switch (cmd) {
3097         case F_SETFL:
3098                 if (!file->f_path.dentry || !file->f_path.dentry->d_inode) {
3099                         err = -EINVAL;
3100                         break;
3101                 }
3102
3103                 if ((file->f_flags & O_APPEND) && !(arg & O_APPEND)) {
3104                         err = file_has_perm(cred, file, FILE__WRITE);
3105                         break;
3106                 }
3107                 /* fall through */
3108         case F_SETOWN:
3109         case F_SETSIG:
3110         case F_GETFL:
3111         case F_GETOWN:
3112         case F_GETSIG:
3113                 /* Just check FD__USE permission */
3114                 err = file_has_perm(cred, file, 0);
3115                 break;
3116         case F_GETLK:
3117         case F_SETLK:
3118         case F_SETLKW:
3119 #if BITS_PER_LONG == 32
3120         case F_GETLK64:
3121         case F_SETLK64:
3122         case F_SETLKW64:
3123 #endif
3124                 if (!file->f_path.dentry || !file->f_path.dentry->d_inode) {
3125                         err = -EINVAL;
3126                         break;
3127                 }
3128                 err = file_has_perm(cred, file, FILE__LOCK);
3129                 break;
3130         }
3131
3132         return err;
3133 }
3134
3135 static int selinux_file_set_fowner(struct file *file)
3136 {
3137         struct file_security_struct *fsec;
3138
3139         fsec = file->f_security;
3140         fsec->fown_sid = current_sid();
3141
3142         return 0;
3143 }
3144
3145 static int selinux_file_send_sigiotask(struct task_struct *tsk,
3146                                        struct fown_struct *fown, int signum)
3147 {
3148         struct file *file;
3149         u32 sid = task_sid(tsk);
3150         u32 perm;
3151         struct file_security_struct *fsec;
3152
3153         /* struct fown_struct is never outside the context of a struct file */
3154         file = container_of(fown, struct file, f_owner);
3155
3156         fsec = file->f_security;
3157
3158         if (!signum)
3159                 perm = signal_to_av(SIGIO); /* as per send_sigio_to_task */
3160         else
3161                 perm = signal_to_av(signum);
3162
3163         return avc_has_perm(fsec->fown_sid, sid,
3164                             SECCLASS_PROCESS, perm, NULL);
3165 }
3166
3167 static int selinux_file_receive(struct file *file)
3168 {
3169         const struct cred *cred = current_cred();
3170
3171         return file_has_perm(cred, file, file_to_av(file));
3172 }
3173
3174 static int selinux_dentry_open(struct file *file, const struct cred *cred)
3175 {
3176         struct file_security_struct *fsec;
3177         struct inode *inode;
3178         struct inode_security_struct *isec;
3179
3180         inode = file->f_path.dentry->d_inode;
3181         fsec = file->f_security;
3182         isec = inode->i_security;
3183         /*
3184          * Save inode label and policy sequence number
3185          * at open-time so that selinux_file_permission
3186          * can determine whether revalidation is necessary.
3187          * Task label is already saved in the file security
3188          * struct as its SID.
3189          */
3190         fsec->isid = isec->sid;
3191         fsec->pseqno = avc_policy_seqno();
3192         /*
3193          * Since the inode label or policy seqno may have changed
3194          * between the selinux_inode_permission check and the saving
3195          * of state above, recheck that access is still permitted.
3196          * Otherwise, access might never be revalidated against the
3197          * new inode label or new policy.
3198          * This check is not redundant - do not remove.
3199          */
3200         return inode_has_perm(cred, inode, open_file_to_av(file), NULL);
3201 }
3202
3203 /* task security operations */
3204
3205 static int selinux_task_create(unsigned long clone_flags)
3206 {
3207         return current_has_perm(current, PROCESS__FORK);
3208 }
3209
3210 /*
3211  * detach and free the LSM part of a set of credentials
3212  */
3213 static void selinux_cred_free(struct cred *cred)
3214 {
3215         struct task_security_struct *tsec = cred->security;
3216         cred->security = NULL;
3217         kfree(tsec);
3218 }
3219
3220 /*
3221  * prepare a new set of credentials for modification
3222  */
3223 static int selinux_cred_prepare(struct cred *new, const struct cred *old,
3224                                 gfp_t gfp)
3225 {
3226         const struct task_security_struct *old_tsec;
3227         struct task_security_struct *tsec;
3228
3229         old_tsec = old->security;
3230
3231         tsec = kmemdup(old_tsec, sizeof(struct task_security_struct), gfp);
3232         if (!tsec)
3233                 return -ENOMEM;
3234
3235         new->security = tsec;
3236         return 0;
3237 }
3238
3239 /*
3240  * set the security data for a kernel service
3241  * - all the creation contexts are set to unlabelled
3242  */
3243 static int selinux_kernel_act_as(struct cred *new, u32 secid)
3244 {
3245         struct task_security_struct *tsec = new->security;
3246         u32 sid = current_sid();
3247         int ret;
3248
3249         ret = avc_has_perm(sid, secid,
3250                            SECCLASS_KERNEL_SERVICE,
3251                            KERNEL_SERVICE__USE_AS_OVERRIDE,
3252                            NULL);
3253         if (ret == 0) {
3254                 tsec->sid = secid;
3255                 tsec->create_sid = 0;
3256                 tsec->keycreate_sid = 0;
3257                 tsec->sockcreate_sid = 0;
3258         }
3259         return ret;
3260 }
3261
3262 /*
3263  * set the file creation context in a security record to the same as the
3264  * objective context of the specified inode
3265  */
3266 static int selinux_kernel_create_files_as(struct cred *new, struct inode *inode)
3267 {
3268         struct inode_security_struct *isec = inode->i_security;
3269         struct task_security_struct *tsec = new->security;
3270         u32 sid = current_sid();
3271         int ret;
3272
3273         ret = avc_has_perm(sid, isec->sid,
3274                            SECCLASS_KERNEL_SERVICE,
3275                            KERNEL_SERVICE__CREATE_FILES_AS,
3276                            NULL);
3277
3278         if (ret == 0)
3279                 tsec->create_sid = isec->sid;
3280         return 0;
3281 }
3282
3283 static int selinux_task_setpgid(struct task_struct *p, pid_t pgid)
3284 {
3285         return current_has_perm(p, PROCESS__SETPGID);
3286 }
3287
3288 static int selinux_task_getpgid(struct task_struct *p)
3289 {
3290         return current_has_perm(p, PROCESS__GETPGID);
3291 }
3292
3293 static int selinux_task_getsid(struct task_struct *p)
3294 {
3295         return current_has_perm(p, PROCESS__GETSESSION);
3296 }
3297
3298 static void selinux_task_getsecid(struct task_struct *p, u32 *secid)
3299 {
3300         *secid = task_sid(p);
3301 }
3302
3303 static int selinux_task_setnice(struct task_struct *p, int nice)
3304 {
3305         int rc;
3306
3307         rc = cap_task_setnice(p, nice);
3308         if (rc)
3309                 return rc;
3310
3311         return current_has_perm(p, PROCESS__SETSCHED);
3312 }
3313
3314 static int selinux_task_setioprio(struct task_struct *p, int ioprio)
3315 {
3316         int rc;
3317
3318         rc = cap_task_setioprio(p, ioprio);
3319         if (rc)
3320                 return rc;
3321
3322         return current_has_perm(p, PROCESS__SETSCHED);
3323 }
3324
3325 static int selinux_task_getioprio(struct task_struct *p)
3326 {
3327         return current_has_perm(p, PROCESS__GETSCHED);
3328 }
3329
3330 static int selinux_task_setrlimit(unsigned int resource, struct rlimit *new_rlim)
3331 {
3332         struct rlimit *old_rlim = current->signal->rlim + resource;
3333
3334         /* Control the ability to change the hard limit (whether
3335            lowering or raising it), so that the hard limit can
3336            later be used as a safe reset point for the soft limit
3337            upon context transitions.  See selinux_bprm_committing_creds. */
3338         if (old_rlim->rlim_max != new_rlim->rlim_max)
3339                 return current_has_perm(current, PROCESS__SETRLIMIT);
3340
3341         return 0;
3342 }
3343
3344 static int selinux_task_setscheduler(struct task_struct *p, int policy, struct sched_param *lp)
3345 {
3346         int rc;
3347
3348         rc = cap_task_setscheduler(p, policy, lp);
3349         if (rc)
3350                 return rc;
3351
3352         return current_has_perm(p, PROCESS__SETSCHED);
3353 }
3354
3355 static int selinux_task_getscheduler(struct task_struct *p)
3356 {
3357         return current_has_perm(p, PROCESS__GETSCHED);
3358 }
3359
3360 static int selinux_task_movememory(struct task_struct *p)
3361 {
3362         return current_has_perm(p, PROCESS__SETSCHED);
3363 }
3364
3365 static int selinux_task_kill(struct task_struct *p, struct siginfo *info,
3366                                 int sig, u32 secid)
3367 {
3368         u32 perm;
3369         int rc;
3370
3371         if (!sig)
3372                 perm = PROCESS__SIGNULL; /* null signal; existence test */
3373         else
3374                 perm = signal_to_av(sig);
3375         if (secid)
3376                 rc = avc_has_perm(secid, task_sid(p),
3377                                   SECCLASS_PROCESS, perm, NULL);
3378         else
3379                 rc = current_has_perm(p, perm);
3380         return rc;
3381 }
3382
3383 static int selinux_task_wait(struct task_struct *p)
3384 {
3385         return task_has_perm(p, current, PROCESS__SIGCHLD);
3386 }
3387
3388 static void selinux_task_to_inode(struct task_struct *p,
3389                                   struct inode *inode)
3390 {
3391         struct inode_security_struct *isec = inode->i_security;
3392         u32 sid = task_sid(p);
3393
3394         isec->sid = sid;
3395         isec->initialized = 1;
3396 }
3397
3398 /* Returns error only if unable to parse addresses */
3399 static int selinux_parse_skb_ipv4(struct sk_buff *skb,
3400                         struct avc_audit_data *ad, u8 *proto)
3401 {
3402         int offset, ihlen, ret = -EINVAL;
3403         struct iphdr _iph, *ih;
3404
3405         offset = skb_network_offset(skb);
3406         ih = skb_header_pointer(skb, offset, sizeof(_iph), &_iph);
3407         if (ih == NULL)
3408                 goto out;
3409
3410         ihlen = ih->ihl * 4;
3411         if (ihlen < sizeof(_iph))
3412                 goto out;
3413
3414         ad->u.net.v4info.saddr = ih->saddr;
3415         ad->u.net.v4info.daddr = ih->daddr;
3416         ret = 0;
3417
3418         if (proto)
3419                 *proto = ih->protocol;
3420
3421         switch (ih->protocol) {
3422         case IPPROTO_TCP: {
3423                 struct tcphdr _tcph, *th;
3424
3425                 if (ntohs(ih->frag_off) & IP_OFFSET)
3426                         break;
3427
3428                 offset += ihlen;
3429                 th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph);
3430                 if (th == NULL)
3431                         break;
3432
3433                 ad->u.net.sport = th->source;
3434                 ad->u.net.dport = th->dest;
3435                 break;
3436         }
3437
3438         case IPPROTO_UDP: {
3439                 struct udphdr _udph, *uh;
3440
3441                 if (ntohs(ih->frag_off) & IP_OFFSET)
3442                         break;
3443
3444                 offset += ihlen;
3445                 uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph);
3446                 if (uh == NULL)
3447                         break;
3448
3449                 ad->u.net.sport = uh->source;
3450                 ad->u.net.dport = uh->dest;
3451                 break;
3452         }
3453
3454         case IPPROTO_DCCP: {
3455                 struct dccp_hdr _dccph, *dh;
3456
3457                 if (ntohs(ih->frag_off) & IP_OFFSET)
3458                         break;
3459
3460                 offset += ihlen;
3461                 dh = skb_header_pointer(skb, offset, sizeof(_dccph), &_dccph);
3462                 if (dh == NULL)
3463                         break;
3464
3465                 ad->u.net.sport = dh->dccph_sport;
3466                 ad->u.net.dport = dh->dccph_dport;
3467                 break;
3468         }
3469
3470         default:
3471                 break;
3472         }
3473 out:
3474         return ret;
3475 }
3476
3477 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
3478
3479 /* Returns error only if unable to parse addresses */
3480 static int selinux_parse_skb_ipv6(struct sk_buff *skb,
3481                         struct avc_audit_data *ad, u8 *proto)
3482 {
3483         u8 nexthdr;
3484         int ret = -EINVAL, offset;
3485         struct ipv6hdr _ipv6h, *ip6;
3486
3487         offset = skb_network_offset(skb);
3488         ip6 = skb_header_pointer(skb, offset, sizeof(_ipv6h), &_ipv6h);
3489         if (ip6 == NULL)
3490                 goto out;
3491
3492         ipv6_addr_copy(&ad->u.net.v6info.saddr, &ip6->saddr);
3493         ipv6_addr_copy(&ad->u.net.v6info.daddr, &ip6->daddr);
3494         ret = 0;
3495
3496         nexthdr = ip6->nexthdr;
3497         offset += sizeof(_ipv6h);
3498         offset = ipv6_skip_exthdr(skb, offset, &nexthdr);
3499         if (offset < 0)
3500                 goto out;
3501
3502         if (proto)
3503                 *proto = nexthdr;
3504
3505         switch (nexthdr) {
3506         case IPPROTO_TCP: {
3507                 struct tcphdr _tcph, *th;
3508
3509                 th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph);
3510                 if (th == NULL)
3511                         break;
3512
3513                 ad->u.net.sport = th->source;
3514                 ad->u.net.dport = th->dest;
3515                 break;
3516         }
3517
3518         case IPPROTO_UDP: {
3519                 struct udphdr _udph, *uh;
3520
3521                 uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph);
3522                 if (uh == NULL)
3523                         break;
3524
3525                 ad->u.net.sport = uh->source;
3526                 ad->u.net.dport = uh->dest;
3527                 break;
3528         }
3529
3530         case IPPROTO_DCCP: {
3531                 struct dccp_hdr _dccph, *dh;
3532
3533                 dh = skb_header_pointer(skb, offset, sizeof(_dccph), &_dccph);
3534                 if (dh == NULL)
3535                         break;
3536
3537                 ad->u.net.sport = dh->dccph_sport;
3538                 ad->u.net.dport = dh->dccph_dport;
3539                 break;
3540         }
3541
3542         /* includes fragments */
3543         default:
3544                 break;
3545         }
3546 out:
3547         return ret;
3548 }
3549
3550 #endif /* IPV6 */
3551
3552 static int selinux_parse_skb(struct sk_buff *skb, struct avc_audit_data *ad,
3553                              char **_addrp, int src, u8 *proto)
3554 {
3555         char *addrp;
3556         int ret;
3557
3558         switch (ad->u.net.family) {
3559         case PF_INET:
3560                 ret = selinux_parse_skb_ipv4(skb, ad, proto);
3561                 if (ret)
3562                         goto parse_error;
3563                 addrp = (char *)(src ? &ad->u.net.v4info.saddr :
3564                                        &ad->u.net.v4info.daddr);
3565                 goto okay;
3566
3567 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
3568         case PF_INET6:
3569                 ret = selinux_parse_skb_ipv6(skb, ad, proto);
3570                 if (ret)
3571                         goto parse_error;
3572                 addrp = (char *)(src ? &ad->u.net.v6info.saddr :
3573                                        &ad->u.net.v6info.daddr);
3574                 goto okay;
3575 #endif  /* IPV6 */
3576         default:
3577                 addrp = NULL;
3578                 goto okay;
3579         }
3580
3581 parse_error:
3582         printk(KERN_WARNING
3583                "SELinux: failure in selinux_parse_skb(),"
3584                " unable to parse packet\n");
3585         return ret;
3586
3587 okay:
3588         if (_addrp)
3589                 *_addrp = addrp;
3590         return 0;
3591 }
3592
3593 /**
3594  * selinux_skb_peerlbl_sid - Determine the peer label of a packet
3595  * @skb: the packet
3596  * @family: protocol family
3597  * @sid: the packet's peer label SID
3598  *
3599  * Description:
3600  * Check the various different forms of network peer labeling and determine
3601  * the peer label/SID for the packet; most of the magic actually occurs in
3602  * the security server function security_net_peersid_cmp().  The function
3603  * returns zero if the value in @sid is valid (although it may be SECSID_NULL)
3604  * or -EACCES if @sid is invalid due to inconsistencies with the different
3605  * peer labels.
3606  *
3607  */
3608 static int selinux_skb_peerlbl_sid(struct sk_buff *skb, u16 family, u32 *sid)
3609 {
3610         int err;
3611         u32 xfrm_sid;
3612         u32 nlbl_sid;
3613         u32 nlbl_type;
3614
3615         selinux_skb_xfrm_sid(skb, &xfrm_sid);
3616         selinux_netlbl_skbuff_getsid(skb, family, &nlbl_type, &nlbl_sid);
3617
3618         err = security_net_peersid_resolve(nlbl_sid, nlbl_type, xfrm_sid, sid);
3619         if (unlikely(err)) {
3620                 printk(KERN_WARNING
3621                        "SELinux: failure in selinux_skb_peerlbl_sid(),"
3622                        " unable to determine packet's peer label\n");
3623                 return -EACCES;
3624         }
3625
3626         return 0;
3627 }
3628
3629 /* socket security operations */
3630 static int socket_has_perm(struct task_struct *task, struct socket *sock,
3631                            u32 perms)
3632 {
3633         struct inode_security_struct *isec;
3634         struct avc_audit_data ad;
3635         u32 sid;
3636         int err = 0;
3637
3638         isec = SOCK_INODE(sock)->i_security;
3639
3640         if (isec->sid == SECINITSID_KERNEL)
3641                 goto out;
3642         sid = task_sid(task);
3643
3644         AVC_AUDIT_DATA_INIT(&ad, NET);
3645         ad.u.net.sk = sock->sk;
3646         err = avc_has_perm(sid, isec->sid, isec->sclass, perms, &ad);
3647
3648 out:
3649         return err;
3650 }
3651
3652 static int selinux_socket_create(int family, int type,
3653                                  int protocol, int kern)
3654 {
3655         const struct cred *cred = current_cred();
3656         const struct task_security_struct *tsec = cred->security;
3657         u32 sid, newsid;
3658         u16 secclass;
3659         int err = 0;
3660
3661         if (kern)
3662                 goto out;
3663
3664         sid = tsec->sid;
3665         newsid = tsec->sockcreate_sid ?: sid;
3666
3667         secclass = socket_type_to_security_class(family, type, protocol);
3668         err = avc_has_perm(sid, newsid, secclass, SOCKET__CREATE, NULL);
3669
3670 out:
3671         return err;
3672 }
3673
3674 static int selinux_socket_post_create(struct socket *sock, int family,
3675                                       int type, int protocol, int kern)
3676 {
3677         const struct cred *cred = current_cred();
3678         const struct task_security_struct *tsec = cred->security;
3679         struct inode_security_struct *isec;
3680         struct sk_security_struct *sksec;
3681         u32 sid, newsid;
3682         int err = 0;
3683
3684         sid = tsec->sid;
3685         newsid = tsec->sockcreate_sid;
3686
3687         isec = SOCK_INODE(sock)->i_security;
3688
3689         if (kern)
3690                 isec->sid = SECINITSID_KERNEL;
3691         else if (newsid)
3692                 isec->sid = newsid;
3693         else
3694                 isec->sid = sid;
3695
3696         isec->sclass = socket_type_to_security_class(family, type, protocol);
3697         isec->initialized = 1;
3698
3699         if (sock->sk) {
3700                 sksec = sock->sk->sk_security;
3701                 sksec->sid = isec->sid;
3702                 sksec->sclass = isec->sclass;
3703                 err = selinux_netlbl_socket_post_create(sock->sk, family);
3704         }
3705
3706         return err;
3707 }
3708
3709 /* Range of port numbers used to automatically bind.
3710    Need to determine whether we should perform a name_bind
3711    permission check between the socket and the port number. */
3712
3713 static int selinux_socket_bind(struct socket *sock, struct sockaddr *address, int addrlen)
3714 {
3715         u16 family;
3716         int err;
3717
3718         err = socket_has_perm(current, sock, SOCKET__BIND);
3719         if (err)
3720                 goto out;
3721
3722         /*
3723          * If PF_INET or PF_INET6, check name_bind permission for the port.
3724          * Multiple address binding for SCTP is not supported yet: we just
3725          * check the first address now.
3726          */
3727         family = sock->sk->sk_family;
3728         if (family == PF_INET || family == PF_INET6) {
3729                 char *addrp;
3730                 struct inode_security_struct *isec;
3731                 struct avc_audit_data ad;
3732                 struct sockaddr_in *addr4 = NULL;
3733                 struct sockaddr_in6 *addr6 = NULL;
3734                 unsigned short snum;
3735                 struct sock *sk = sock->sk;
3736                 u32 sid, node_perm;
3737
3738                 isec = SOCK_INODE(sock)->i_security;
3739
3740                 if (family == PF_INET) {
3741                         addr4 = (struct sockaddr_in *)address;
3742                         snum = ntohs(addr4->sin_port);
3743                         addrp = (char *)&addr4->sin_addr.s_addr;
3744                 } else {
3745                         addr6 = (struct sockaddr_in6 *)address;
3746                         snum = ntohs(addr6->sin6_port);
3747                         addrp = (char *)&addr6->sin6_addr.s6_addr;
3748                 }
3749
3750                 if (snum) {
3751                         int low, high;
3752
3753                         inet_get_local_port_range(&low, &high);
3754
3755                         if (snum < max(PROT_SOCK, low) || snum > high) {
3756                                 err = sel_netport_sid(sk->sk_protocol,
3757                                                       snum, &sid);
3758                                 if (err)
3759                                         goto out;
3760                                 AVC_AUDIT_DATA_INIT(&ad, NET);
3761                                 ad.u.net.sport = htons(snum);
3762                                 ad.u.net.family = family;
3763                                 err = avc_has_perm(isec->sid, sid,
3764                                                    isec->sclass,
3765                                                    SOCKET__NAME_BIND, &ad);
3766                                 if (err)
3767                                         goto out;
3768                         }
3769                 }
3770
3771                 switch (isec->sclass) {
3772                 case SECCLASS_TCP_SOCKET:
3773                         node_perm = TCP_SOCKET__NODE_BIND;
3774                         break;
3775
3776                 case SECCLASS_UDP_SOCKET:
3777                         node_perm = UDP_SOCKET__NODE_BIND;
3778                         break;
3779
3780                 case SECCLASS_DCCP_SOCKET:
3781                         node_perm = DCCP_SOCKET__NODE_BIND;
3782                         break;
3783
3784                 default:
3785                         node_perm = RAWIP_SOCKET__NODE_BIND;
3786                         break;
3787                 }
3788
3789                 err = sel_netnode_sid(addrp, family, &sid);
3790                 if (err)
3791                         goto out;
3792
3793                 AVC_AUDIT_DATA_INIT(&ad, NET);
3794                 ad.u.net.sport = htons(snum);
3795                 ad.u.net.family = family;
3796
3797                 if (family == PF_INET)
3798                         ad.u.net.v4info.saddr = addr4->sin_addr.s_addr;
3799                 else
3800                         ipv6_addr_copy(&ad.u.net.v6info.saddr, &addr6->sin6_addr);
3801
3802                 err = avc_has_perm(isec->sid, sid,
3803                                    isec->sclass, node_perm, &ad);
3804                 if (err)
3805                         goto out;
3806         }
3807 out:
3808         return err;
3809 }
3810
3811 static int selinux_socket_connect(struct socket *sock, struct sockaddr *address, int addrlen)
3812 {
3813         struct sock *sk = sock->sk;
3814         struct inode_security_struct *isec;
3815         int err;
3816
3817         err = socket_has_perm(current, sock, SOCKET__CONNECT);
3818         if (err)
3819                 return err;
3820
3821         /*
3822          * If a TCP or DCCP socket, check name_connect permission for the port.
3823          */
3824         isec = SOCK_INODE(sock)->i_security;
3825         if (isec->sclass == SECCLASS_TCP_SOCKET ||
3826             isec->sclass == SECCLASS_DCCP_SOCKET) {
3827                 struct avc_audit_data ad;
3828                 struct sockaddr_in *addr4 = NULL;
3829                 struct sockaddr_in6 *addr6 = NULL;
3830                 unsigned short snum;
3831                 u32 sid, perm;
3832
3833                 if (sk->sk_family == PF_INET) {
3834                         addr4 = (struct sockaddr_in *)address;
3835                         if (addrlen < sizeof(struct sockaddr_in))
3836                                 return -EINVAL;
3837                         snum = ntohs(addr4->sin_port);
3838                 } else {
3839                         addr6 = (struct sockaddr_in6 *)address;
3840                         if (addrlen < SIN6_LEN_RFC2133)
3841                                 return -EINVAL;
3842                         snum = ntohs(addr6->sin6_port);
3843                 }
3844
3845                 err = sel_netport_sid(sk->sk_protocol, snum, &sid);
3846                 if (err)
3847                         goto out;
3848
3849                 perm = (isec->sclass == SECCLASS_TCP_SOCKET) ?
3850                        TCP_SOCKET__NAME_CONNECT : DCCP_SOCKET__NAME_CONNECT;
3851
3852                 AVC_AUDIT_DATA_INIT(&ad, NET);
3853                 ad.u.net.dport = htons(snum);
3854                 ad.u.net.family = sk->sk_family;
3855                 err = avc_has_perm(isec->sid, sid, isec->sclass, perm, &ad);
3856                 if (err)
3857                         goto out;
3858         }
3859
3860         err = selinux_netlbl_socket_connect(sk, address);
3861
3862 out:
3863         return err;
3864 }
3865
3866 static int selinux_socket_listen(struct socket *sock, int backlog)
3867 {
3868         return socket_has_perm(current, sock, SOCKET__LISTEN);
3869 }
3870
3871 static int selinux_socket_accept(struct socket *sock, struct socket *newsock)
3872 {
3873         int err;
3874         struct inode_security_struct *isec;
3875         struct inode_security_struct *newisec;
3876
3877         err = socket_has_perm(current, sock, SOCKET__ACCEPT);
3878         if (err)
3879                 return err;
3880
3881         newisec = SOCK_INODE(newsock)->i_security;
3882
3883         isec = SOCK_INODE(sock)->i_security;
3884         newisec->sclass = isec->sclass;
3885         newisec->sid = isec->sid;
3886         newisec->initialized = 1;
3887
3888         return 0;
3889 }
3890
3891 static int selinux_socket_sendmsg(struct socket *sock, struct msghdr *msg,
3892                                   int size)
3893 {
3894         return socket_has_perm(current, sock, SOCKET__WRITE);
3895 }
3896
3897 static int selinux_socket_recvmsg(struct socket *sock, struct msghdr *msg,
3898                                   int size, int flags)
3899 {
3900         return socket_has_perm(current, sock, SOCKET__READ);
3901 }
3902
3903 static int selinux_socket_getsockname(struct socket *sock)
3904 {
3905         return socket_has_perm(current, sock, SOCKET__GETATTR);
3906 }
3907
3908 static int selinux_socket_getpeername(struct socket *sock)
3909 {
3910         return socket_has_perm(current, sock, SOCKET__GETATTR);
3911 }
3912
3913 static int selinux_socket_setsockopt(struct socket *sock, int level, int optname)
3914 {
3915         int err;
3916
3917         err = socket_has_perm(current, sock, SOCKET__SETOPT);
3918         if (err)
3919                 return err;
3920
3921         return selinux_netlbl_socket_setsockopt(sock, level, optname);
3922 }
3923
3924 static int selinux_socket_getsockopt(struct socket *sock, int level,
3925                                      int optname)
3926 {
3927         return socket_has_perm(current, sock, SOCKET__GETOPT);
3928 }
3929
3930 static int selinux_socket_shutdown(struct socket *sock, int how)
3931 {
3932         return socket_has_perm(current, sock, SOCKET__SHUTDOWN);
3933 }
3934
3935 static int selinux_socket_unix_stream_connect(struct socket *sock,
3936                                               struct socket *other,
3937                                               struct sock *newsk)
3938 {
3939         struct sk_security_struct *ssec;
3940         struct inode_security_struct *isec;
3941         struct inode_security_struct *other_isec;
3942         struct avc_audit_data ad;
3943         int err;
3944
3945         isec = SOCK_INODE(sock)->i_security;
3946         other_isec = SOCK_INODE(other)->i_security;
3947
3948         AVC_AUDIT_DATA_INIT(&ad, NET);
3949         ad.u.net.sk = other->sk;
3950
3951         err = avc_has_perm(isec->sid, other_isec->sid,
3952                            isec->sclass,
3953                            UNIX_STREAM_SOCKET__CONNECTTO, &ad);
3954         if (err)
3955                 return err;
3956
3957         /* connecting socket */
3958         ssec = sock->sk->sk_security;
3959         ssec->peer_sid = other_isec->sid;
3960
3961         /* server child socket */
3962         ssec = newsk->sk_security;
3963         ssec->peer_sid = isec->sid;
3964         err = security_sid_mls_copy(other_isec->sid, ssec->peer_sid, &ssec->sid);
3965
3966         return err;
3967 }
3968
3969 static int selinux_socket_unix_may_send(struct socket *sock,
3970                                         struct socket *other)
3971 {
3972         struct inode_security_struct *isec;
3973         struct inode_security_struct *other_isec;
3974         struct avc_audit_data ad;
3975         int err;
3976
3977         isec = SOCK_INODE(sock)->i_security;
3978         other_isec = SOCK_INODE(other)->i_security;
3979
3980         AVC_AUDIT_DATA_INIT(&ad, NET);
3981         ad.u.net.sk = other->sk;
3982
3983         err = avc_has_perm(isec->sid, other_isec->sid,
3984                            isec->sclass, SOCKET__SENDTO, &ad);
3985         if (err)
3986                 return err;
3987
3988         return 0;
3989 }
3990
3991 static int selinux_inet_sys_rcv_skb(int ifindex, char *addrp, u16 family,
3992                                     u32 peer_sid,
3993                                     struct avc_audit_data *ad)
3994 {
3995         int err;
3996         u32 if_sid;
3997         u32 node_sid;
3998
3999         err = sel_netif_sid(ifindex, &if_sid);
4000         if (err)
4001                 return err;
4002         err = avc_has_perm(peer_sid, if_sid,
4003                            SECCLASS_NETIF, NETIF__INGRESS, ad);
4004         if (err)
4005                 return err;
4006
4007         err = sel_netnode_sid(addrp, family, &node_sid);
4008         if (err)
4009                 return err;
4010         return avc_has_perm(peer_sid, node_sid,
4011                             SECCLASS_NODE, NODE__RECVFROM, ad);
4012 }
4013
4014 static int selinux_sock_rcv_skb_compat(struct sock *sk, struct sk_buff *skb,
4015                                        u16 family)
4016 {
4017         int err = 0;
4018         struct sk_security_struct *sksec = sk->sk_security;
4019         u32 peer_sid;
4020         u32 sk_sid = sksec->sid;
4021         struct avc_audit_data ad;
4022         char *addrp;
4023
4024         AVC_AUDIT_DATA_INIT(&ad, NET);
4025         ad.u.net.netif = skb->iif;
4026         ad.u.net.family = family;
4027         err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL);
4028         if (err)
4029                 return err;
4030
4031         if (selinux_secmark_enabled()) {
4032                 err = avc_has_perm(sk_sid, skb->secmark, SECCLASS_PACKET,
4033                                    PACKET__RECV, &ad);
4034                 if (err)
4035                         return err;
4036         }
4037
4038         if (selinux_policycap_netpeer) {
4039                 err = selinux_skb_peerlbl_sid(skb, family, &peer_sid);
4040                 if (err)
4041                         return err;
4042                 err = avc_has_perm(sk_sid, peer_sid,
4043                                    SECCLASS_PEER, PEER__RECV, &ad);
4044                 if (err)
4045                         selinux_netlbl_err(skb, err, 0);
4046         } else {
4047                 err = selinux_netlbl_sock_rcv_skb(sksec, skb, family, &ad);
4048                 if (err)
4049                         return err;
4050                 err = selinux_xfrm_sock_rcv_skb(sksec->sid, skb, &ad);
4051         }
4052
4053         return err;
4054 }
4055
4056 static int selinux_socket_sock_rcv_skb(struct sock *sk, struct sk_buff *skb)
4057 {
4058         int err;
4059         struct sk_security_struct *sksec = sk->sk_security;
4060         u16 family = sk->sk_family;
4061         u32 sk_sid = sksec->sid;
4062         struct avc_audit_data ad;
4063         char *addrp;
4064         u8 secmark_active;
4065         u8 peerlbl_active;
4066
4067         if (family != PF_INET && family != PF_INET6)
4068                 return 0;
4069
4070         /* Handle mapped IPv4 packets arriving via IPv6 sockets */
4071         if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
4072                 family = PF_INET;
4073
4074         /* If any sort of compatibility mode is enabled then handoff processing
4075          * to the selinux_sock_rcv_skb_compat() function to deal with the
4076          * special handling.  We do this in an attempt to keep this function
4077          * as fast and as clean as possible. */
4078         if (!selinux_policycap_netpeer)
4079                 return selinux_sock_rcv_skb_compat(sk, skb, family);
4080
4081         secmark_active = selinux_secmark_enabled();
4082         peerlbl_active = netlbl_enabled() || selinux_xfrm_enabled();
4083         if (!secmark_active && !peerlbl_active)
4084                 return 0;
4085
4086         AVC_AUDIT_DATA_INIT(&ad, NET);
4087         ad.u.net.netif = skb->iif;
4088         ad.u.net.family = family;
4089         err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL);
4090         if (err)
4091                 return err;
4092
4093         if (peerlbl_active) {
4094                 u32 peer_sid;
4095
4096                 err = selinux_skb_peerlbl_sid(skb, family, &peer_sid);
4097                 if (err)
4098                         return err;
4099                 err = selinux_inet_sys_rcv_skb(skb->iif, addrp, family,
4100                                                peer_sid, &ad);
4101                 if (err) {
4102                         selinux_netlbl_err(skb, err, 0);
4103                         return err;
4104                 }
4105                 err = avc_has_perm(sk_sid, peer_sid, SECCLASS_PEER,
4106                                    PEER__RECV, &ad);
4107                 if (err)
4108                         selinux_netlbl_err(skb, err, 0);
4109         }
4110
4111         if (secmark_active) {
4112                 err = avc_has_perm(sk_sid, skb->secmark, SECCLASS_PACKET,
4113                                    PACKET__RECV, &ad);
4114                 if (err)
4115                         return err;
4116         }
4117
4118         return err;
4119 }
4120
4121 static int selinux_socket_getpeersec_stream(struct socket *sock, char __user *optval,
4122                                             int __user *optlen, unsigned len)
4123 {
4124         int err = 0;
4125         char *scontext;
4126         u32 scontext_len;
4127         struct sk_security_struct *ssec;
4128         struct inode_security_struct *isec;
4129         u32 peer_sid = SECSID_NULL;
4130
4131         isec = SOCK_INODE(sock)->i_security;
4132
4133         if (isec->sclass == SECCLASS_UNIX_STREAM_SOCKET ||
4134             isec->sclass == SECCLASS_TCP_SOCKET) {
4135                 ssec = sock->sk->sk_security;
4136                 peer_sid = ssec->peer_sid;
4137         }
4138         if (peer_sid == SECSID_NULL) {
4139                 err = -ENOPROTOOPT;
4140                 goto out;
4141         }
4142
4143         err = security_sid_to_context(peer_sid, &scontext, &scontext_len);
4144
4145         if (err)
4146                 goto out;
4147
4148         if (scontext_len > len) {
4149                 err = -ERANGE;
4150                 goto out_len;
4151         }
4152
4153         if (copy_to_user(optval, scontext, scontext_len))
4154                 err = -EFAULT;
4155
4156 out_len:
4157         if (put_user(scontext_len, optlen))
4158                 err = -EFAULT;
4159
4160         kfree(scontext);
4161 out:
4162         return err;
4163 }
4164
4165 static int selinux_socket_getpeersec_dgram(struct socket *sock, struct sk_buff *skb, u32 *secid)
4166 {
4167         u32 peer_secid = SECSID_NULL;
4168         u16 family;
4169
4170         if (skb && skb->protocol == htons(ETH_P_IP))
4171                 family = PF_INET;
4172         else if (skb && skb->protocol == htons(ETH_P_IPV6))
4173                 family = PF_INET6;
4174         else if (sock)
4175                 family = sock->sk->sk_family;
4176         else
4177                 goto out;
4178
4179         if (sock && family == PF_UNIX)
4180                 selinux_inode_getsecid(SOCK_INODE(sock), &peer_secid);
4181         else if (skb)
4182                 selinux_skb_peerlbl_sid(skb, family, &peer_secid);
4183
4184 out:
4185         *secid = peer_secid;
4186         if (peer_secid == SECSID_NULL)
4187                 return -EINVAL;
4188         return 0;
4189 }
4190
4191 static int selinux_sk_alloc_security(struct sock *sk, int family, gfp_t priority)
4192 {
4193         return sk_alloc_security(sk, family, priority);
4194 }
4195
4196 static void selinux_sk_free_security(struct sock *sk)
4197 {
4198         sk_free_security(sk);
4199 }
4200
4201 static void selinux_sk_clone_security(const struct sock *sk, struct sock *newsk)
4202 {
4203         struct sk_security_struct *ssec = sk->sk_security;
4204         struct sk_security_struct *newssec = newsk->sk_security;
4205
4206         newssec->sid = ssec->sid;
4207         newssec->peer_sid = ssec->peer_sid;
4208         newssec->sclass = ssec->sclass;
4209
4210         selinux_netlbl_sk_security_reset(newssec);
4211 }
4212
4213 static void selinux_sk_getsecid(struct sock *sk, u32 *secid)
4214 {
4215         if (!sk)
4216                 *secid = SECINITSID_ANY_SOCKET;
4217         else {
4218                 struct sk_security_struct *sksec = sk->sk_security;
4219
4220                 *secid = sksec->sid;
4221         }
4222 }
4223
4224 static void selinux_sock_graft(struct sock *sk, struct socket *parent)
4225 {
4226         struct inode_security_struct *isec = SOCK_INODE(parent)->i_security;
4227         struct sk_security_struct *sksec = sk->sk_security;
4228
4229         if (sk->sk_family == PF_INET || sk->sk_family == PF_INET6 ||
4230             sk->sk_family == PF_UNIX)
4231                 isec->sid = sksec->sid;
4232         sksec->sclass = isec->sclass;
4233 }
4234
4235 static int selinux_inet_conn_request(struct sock *sk, struct sk_buff *skb,
4236                                      struct request_sock *req)
4237 {
4238         struct sk_security_struct *sksec = sk->sk_security;
4239         int err;
4240         u16 family = sk->sk_family;
4241         u32 newsid;
4242         u32 peersid;
4243
4244         /* handle mapped IPv4 packets arriving via IPv6 sockets */
4245         if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
4246                 family = PF_INET;
4247
4248         err = selinux_skb_peerlbl_sid(skb, family, &peersid);
4249         if (err)
4250                 return err;
4251         if (peersid == SECSID_NULL) {
4252                 req->secid = sksec->sid;
4253                 req->peer_secid = SECSID_NULL;
4254         } else {
4255                 err = security_sid_mls_copy(sksec->sid, peersid, &newsid);
4256                 if (err)
4257                         return err;
4258                 req->secid = newsid;
4259                 req->peer_secid = peersid;
4260         }
4261
4262         return selinux_netlbl_inet_conn_request(req, family);
4263 }
4264
4265 static void selinux_inet_csk_clone(struct sock *newsk,
4266                                    const struct request_sock *req)
4267 {
4268         struct sk_security_struct *newsksec = newsk->sk_security;
4269
4270         newsksec->sid = req->secid;
4271         newsksec->peer_sid = req->peer_secid;
4272         /* NOTE: Ideally, we should also get the isec->sid for the
4273            new socket in sync, but we don't have the isec available yet.
4274            So we will wait until sock_graft to do it, by which
4275            time it will have been created and available. */
4276
4277         /* We don't need to take any sort of lock here as we are the only
4278          * thread with access to newsksec */
4279         selinux_netlbl_inet_csk_clone(newsk, req->rsk_ops->family);
4280 }
4281
4282 static void selinux_inet_conn_established(struct sock *sk, struct sk_buff *skb)
4283 {
4284         u16 family = sk->sk_family;
4285         struct sk_security_struct *sksec = sk->sk_security;
4286
4287         /* handle mapped IPv4 packets arriving via IPv6 sockets */
4288         if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
4289                 family = PF_INET;
4290
4291         selinux_skb_peerlbl_sid(skb, family, &sksec->peer_sid);
4292 }
4293
4294 static void selinux_req_classify_flow(const struct request_sock *req,
4295                                       struct flowi *fl)
4296 {
4297         fl->secid = req->secid;
4298 }
4299
4300 static int selinux_nlmsg_perm(struct sock *sk, struct sk_buff *skb)
4301 {
4302         int err = 0;
4303         u32 perm;
4304         struct nlmsghdr *nlh;
4305         struct socket *sock = sk->sk_socket;
4306         struct inode_security_struct *isec = SOCK_INODE(sock)->i_security;
4307
4308         if (skb->len < NLMSG_SPACE(0)) {
4309                 err = -EINVAL;
4310                 goto out;
4311         }
4312         nlh = nlmsg_hdr(skb);
4313
4314         err = selinux_nlmsg_lookup(isec->sclass, nlh->nlmsg_type, &perm);
4315         if (err) {
4316                 if (err == -EINVAL) {
4317                         audit_log(current->audit_context, GFP_KERNEL, AUDIT_SELINUX_ERR,
4318                                   "SELinux:  unrecognized netlink message"
4319                                   " type=%hu for sclass=%hu\n",
4320                                   nlh->nlmsg_type, isec->sclass);
4321                         if (!selinux_enforcing || security_get_allow_unknown())
4322                                 err = 0;
4323                 }
4324
4325                 /* Ignore */
4326                 if (err == -ENOENT)
4327                         err = 0;
4328                 goto out;
4329         }
4330
4331         err = socket_has_perm(current, sock, perm);
4332 out:
4333         return err;
4334 }
4335
4336 #ifdef CONFIG_NETFILTER
4337
4338 static unsigned int selinux_ip_forward(struct sk_buff *skb, int ifindex,
4339                                        u16 family)
4340 {
4341         int err;
4342         char *addrp;
4343         u32 peer_sid;
4344         struct avc_audit_data ad;
4345         u8 secmark_active;
4346         u8 netlbl_active;
4347         u8 peerlbl_active;
4348
4349         if (!selinux_policycap_netpeer)
4350                 return NF_ACCEPT;
4351
4352         secmark_active = selinux_secmark_enabled();
4353         netlbl_active = netlbl_enabled();
4354         peerlbl_active = netlbl_active || selinux_xfrm_enabled();
4355         if (!secmark_active && !peerlbl_active)
4356                 return NF_ACCEPT;
4357
4358         if (selinux_skb_peerlbl_sid(skb, family, &peer_sid) != 0)
4359                 return NF_DROP;
4360
4361         AVC_AUDIT_DATA_INIT(&ad, NET);
4362         ad.u.net.netif = ifindex;
4363         ad.u.net.family = family;
4364         if (selinux_parse_skb(skb, &ad, &addrp, 1, NULL) != 0)
4365                 return NF_DROP;
4366
4367         if (peerlbl_active) {
4368                 err = selinux_inet_sys_rcv_skb(ifindex, addrp, family,
4369                                                peer_sid, &ad);
4370                 if (err) {
4371                         selinux_netlbl_err(skb, err, 1);
4372                         return NF_DROP;
4373                 }
4374         }
4375
4376         if (secmark_active)
4377                 if (avc_has_perm(peer_sid, skb->secmark,
4378                                  SECCLASS_PACKET, PACKET__FORWARD_IN, &ad))
4379                         return NF_DROP;
4380
4381         if (netlbl_active)
4382                 /* we do this in the FORWARD path and not the POST_ROUTING
4383                  * path because we want to make sure we apply the necessary
4384                  * labeling before IPsec is applied so we can leverage AH
4385                  * protection */
4386                 if (selinux_netlbl_skbuff_setsid(skb, family, peer_sid) != 0)
4387                         return NF_DROP;
4388
4389         return NF_ACCEPT;
4390 }
4391
4392 static unsigned int selinux_ipv4_forward(unsigned int hooknum,
4393                                          struct sk_buff *skb,
4394                                          const struct net_device *in,
4395                                          const struct net_device *out,
4396                                          int (*okfn)(struct sk_buff *))
4397 {
4398         return selinux_ip_forward(skb, in->ifindex, PF_INET);
4399 }
4400
4401 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
4402 static unsigned int selinux_ipv6_forward(unsigned int hooknum,
4403                                          struct sk_buff *skb,
4404                                          const struct net_device *in,
4405                                          const struct net_device *out,
4406                                          int (*okfn)(struct sk_buff *))
4407 {
4408         return selinux_ip_forward(skb, in->ifindex, PF_INET6);
4409 }
4410 #endif  /* IPV6 */
4411
4412 static unsigned int selinux_ip_output(struct sk_buff *skb,
4413                                       u16 family)
4414 {
4415         u32 sid;
4416
4417         if (!netlbl_enabled())
4418                 return NF_ACCEPT;
4419
4420         /* we do this in the LOCAL_OUT path and not the POST_ROUTING path
4421          * because we want to make sure we apply the necessary labeling
4422          * before IPsec is applied so we can leverage AH protection */
4423         if (skb->sk) {
4424                 struct sk_security_struct *sksec = skb->sk->sk_security;
4425                 sid = sksec->sid;
4426         } else
4427                 sid = SECINITSID_KERNEL;
4428         if (selinux_netlbl_skbuff_setsid(skb, family, sid) != 0)
4429                 return NF_DROP;
4430
4431         return NF_ACCEPT;
4432 }
4433
4434 static unsigned int selinux_ipv4_output(unsigned int hooknum,
4435                                         struct sk_buff *skb,
4436                                         const struct net_device *in,
4437                                         const struct net_device *out,
4438                                         int (*okfn)(struct sk_buff *))
4439 {
4440         return selinux_ip_output(skb, PF_INET);
4441 }
4442
4443 static unsigned int selinux_ip_postroute_compat(struct sk_buff *skb,
4444                                                 int ifindex,
4445                                                 u16 family)
4446 {
4447         struct sock *sk = skb->sk;
4448         struct sk_security_struct *sksec;
4449         struct avc_audit_data ad;
4450         char *addrp;
4451         u8 proto;
4452
4453         if (sk == NULL)
4454                 return NF_ACCEPT;
4455         sksec = sk->sk_security;
4456
4457         AVC_AUDIT_DATA_INIT(&ad, NET);
4458         ad.u.net.netif = ifindex;
4459         ad.u.net.family = family;
4460         if (selinux_parse_skb(skb, &ad, &addrp, 0, &proto))
4461                 return NF_DROP;
4462
4463         if (selinux_secmark_enabled())
4464                 if (avc_has_perm(sksec->sid, skb->secmark,
4465                                  SECCLASS_PACKET, PACKET__SEND, &ad))
4466                         return NF_DROP;
4467
4468         if (selinux_policycap_netpeer)
4469                 if (selinux_xfrm_postroute_last(sksec->sid, skb, &ad, proto))
4470                         return NF_DROP;
4471
4472         return NF_ACCEPT;
4473 }
4474
4475 static unsigned int selinux_ip_postroute(struct sk_buff *skb, int ifindex,
4476                                          u16 family)
4477 {
4478         u32 secmark_perm;
4479         u32 peer_sid;
4480         struct sock *sk;
4481         struct avc_audit_data ad;
4482         char *addrp;
4483         u8 secmark_active;
4484         u8 peerlbl_active;
4485
4486         /* If any sort of compatibility mode is enabled then handoff processing
4487          * to the selinux_ip_postroute_compat() function to deal with the
4488          * special handling.  We do this in an attempt to keep this function
4489          * as fast and as clean as possible. */
4490         if (!selinux_policycap_netpeer)
4491                 return selinux_ip_postroute_compat(skb, ifindex, family);
4492 #ifdef CONFIG_XFRM
4493         /* If skb->dst->xfrm is non-NULL then the packet is undergoing an IPsec
4494          * packet transformation so allow the packet to pass without any checks
4495          * since we'll have another chance to perform access control checks
4496          * when the packet is on it's final way out.
4497          * NOTE: there appear to be some IPv6 multicast cases where skb->dst
4498          *       is NULL, in this case go ahead and apply access control. */
4499         if (skb_dst(skb) != NULL && skb_dst(skb)->xfrm != NULL)
4500                 return NF_ACCEPT;
4501 #endif
4502         secmark_active = selinux_secmark_enabled();
4503         peerlbl_active = netlbl_enabled() || selinux_xfrm_enabled();
4504         if (!secmark_active && !peerlbl_active)
4505                 return NF_ACCEPT;
4506
4507         /* if the packet is being forwarded then get the peer label from the
4508          * packet itself; otherwise check to see if it is from a local
4509          * application or the kernel, if from an application get the peer label
4510          * from the sending socket, otherwise use the kernel's sid */
4511         sk = skb->sk;
4512         if (sk == NULL) {
4513                 switch (family) {
4514                 case PF_INET:
4515                         if (IPCB(skb)->flags & IPSKB_FORWARDED)
4516                                 secmark_perm = PACKET__FORWARD_OUT;
4517                         else
4518                                 secmark_perm = PACKET__SEND;
4519                         break;
4520                 case PF_INET6:
4521                         if (IP6CB(skb)->flags & IP6SKB_FORWARDED)
4522                                 secmark_perm = PACKET__FORWARD_OUT;
4523                         else
4524                                 secmark_perm = PACKET__SEND;
4525                         break;
4526                 default:
4527                         return NF_DROP;
4528                 }
4529                 if (secmark_perm == PACKET__FORWARD_OUT) {
4530                         if (selinux_skb_peerlbl_sid(skb, family, &peer_sid))
4531                                 return NF_DROP;
4532                 } else
4533                         peer_sid = SECINITSID_KERNEL;
4534         } else {
4535                 struct sk_security_struct *sksec = sk->sk_security;
4536                 peer_sid = sksec->sid;
4537                 secmark_perm = PACKET__SEND;
4538         }
4539
4540         AVC_AUDIT_DATA_INIT(&ad, NET);
4541         ad.u.net.netif = ifindex;
4542         ad.u.net.family = family;
4543         if (selinux_parse_skb(skb, &ad, &addrp, 0, NULL))
4544                 return NF_DROP;
4545
4546         if (secmark_active)
4547                 if (avc_has_perm(peer_sid, skb->secmark,
4548                                  SECCLASS_PACKET, secmark_perm, &ad))
4549                         return NF_DROP;
4550
4551         if (peerlbl_active) {
4552                 u32 if_sid;
4553                 u32 node_sid;
4554
4555                 if (sel_netif_sid(ifindex, &if_sid))
4556                         return NF_DROP;
4557                 if (avc_has_perm(peer_sid, if_sid,
4558                                  SECCLASS_NETIF, NETIF__EGRESS, &ad))
4559                         return NF_DROP;
4560
4561                 if (sel_netnode_sid(addrp, family, &node_sid))
4562                         return NF_DROP;
4563                 if (avc_has_perm(peer_sid, node_sid,
4564                                  SECCLASS_NODE, NODE__SENDTO, &ad))
4565                         return NF_DROP;
4566         }
4567
4568         return NF_ACCEPT;
4569 }
4570
4571 static unsigned int selinux_ipv4_postroute(unsigned int hooknum,
4572                                            struct sk_buff *skb,
4573                                            const struct net_device *in,
4574                                            const struct net_device *out,
4575                                            int (*okfn)(struct sk_buff *))
4576 {
4577         return selinux_ip_postroute(skb, out->ifindex, PF_INET);
4578 }
4579
4580 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
4581 static unsigned int selinux_ipv6_postroute(unsigned int hooknum,
4582                                            struct sk_buff *skb,
4583                                            const struct net_device *in,
4584                                            const struct net_device *out,
4585                                            int (*okfn)(struct sk_buff *))
4586 {
4587         return selinux_ip_postroute(skb, out->ifindex, PF_INET6);
4588 }
4589 #endif  /* IPV6 */
4590
4591 #endif  /* CONFIG_NETFILTER */
4592
4593 static int selinux_netlink_send(struct sock *sk, struct sk_buff *skb)
4594 {
4595         int err;
4596
4597         err = cap_netlink_send(sk, skb);
4598         if (err)
4599                 return err;
4600
4601         if (policydb_loaded_version >= POLICYDB_VERSION_NLCLASS)
4602                 err = selinux_nlmsg_perm(sk, skb);
4603
4604         return err;
4605 }
4606
4607 static int selinux_netlink_recv(struct sk_buff *skb, int capability)
4608 {
4609         int err;
4610         struct avc_audit_data ad;
4611
4612         err = cap_netlink_recv(skb, capability);
4613         if (err)
4614                 return err;
4615
4616         AVC_AUDIT_DATA_INIT(&ad, CAP);
4617         ad.u.cap = capability;
4618
4619         return avc_has_perm(NETLINK_CB(skb).sid, NETLINK_CB(skb).sid,
4620                             SECCLASS_CAPABILITY, CAP_TO_MASK(capability), &ad);
4621 }
4622
4623 static int ipc_alloc_security(struct task_struct *task,
4624                               struct kern_ipc_perm *perm,
4625                               u16 sclass)
4626 {
4627         struct ipc_security_struct *isec;
4628         u32 sid;
4629
4630         isec = kzalloc(sizeof(struct ipc_security_struct), GFP_KERNEL);
4631         if (!isec)
4632                 return -ENOMEM;
4633
4634         sid = task_sid(task);
4635         isec->sclass = sclass;
4636         isec->sid = sid;
4637         perm->security = isec;
4638
4639         return 0;
4640 }
4641
4642 static void ipc_free_security(struct kern_ipc_perm *perm)
4643 {
4644         struct ipc_security_struct *isec = perm->security;
4645         perm->security = NULL;
4646         kfree(isec);
4647 }
4648
4649 static int msg_msg_alloc_security(struct msg_msg *msg)
4650 {
4651         struct msg_security_struct *msec;
4652
4653         msec = kzalloc(sizeof(struct msg_security_struct), GFP_KERNEL);
4654         if (!msec)
4655                 return -ENOMEM;
4656
4657         msec->sid = SECINITSID_UNLABELED;
4658         msg->security = msec;
4659
4660         return 0;
4661 }
4662
4663 static void msg_msg_free_security(struct msg_msg *msg)
4664 {
4665         struct msg_security_struct *msec = msg->security;
4666
4667         msg->security = NULL;
4668         kfree(msec);
4669 }
4670
4671 static int ipc_has_perm(struct kern_ipc_perm *ipc_perms,
4672                         u32 perms)
4673 {
4674         struct ipc_security_struct *isec;
4675         struct avc_audit_data ad;
4676         u32 sid = current_sid();
4677
4678         isec = ipc_perms->security;
4679
4680         AVC_AUDIT_DATA_INIT(&ad, IPC);
4681         ad.u.ipc_id = ipc_perms->key;
4682
4683         return avc_has_perm(sid, isec->sid, isec->sclass, perms, &ad);
4684 }
4685
4686 static int selinux_msg_msg_alloc_security(struct msg_msg *msg)
4687 {
4688         return msg_msg_alloc_security(msg);
4689 }
4690
4691 static void selinux_msg_msg_free_security(struct msg_msg *msg)
4692 {
4693         msg_msg_free_security(msg);
4694 }
4695
4696 /* message queue security operations */
4697 static int selinux_msg_queue_alloc_security(struct msg_queue *msq)
4698 {
4699         struct ipc_security_struct *isec;
4700         struct avc_audit_data ad;
4701         u32 sid = current_sid();
4702         int rc;
4703
4704         rc = ipc_alloc_security(current, &msq->q_perm, SECCLASS_MSGQ);
4705         if (rc)
4706                 return rc;
4707
4708         isec = msq->q_perm.security;
4709
4710         AVC_AUDIT_DATA_INIT(&ad, IPC);
4711         ad.u.ipc_id = msq->q_perm.key;
4712
4713         rc = avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
4714                           MSGQ__CREATE, &ad);
4715         if (rc) {
4716                 ipc_free_security(&msq->q_perm);
4717                 return rc;
4718         }
4719         return 0;
4720 }
4721
4722 static void selinux_msg_queue_free_security(struct msg_queue *msq)
4723 {
4724         ipc_free_security(&msq->q_perm);
4725 }
4726
4727 static int selinux_msg_queue_associate(struct msg_queue *msq, int msqflg)
4728 {
4729         struct ipc_security_struct *isec;
4730         struct avc_audit_data ad;
4731         u32 sid = current_sid();
4732
4733         isec = msq->q_perm.security;
4734
4735         AVC_AUDIT_DATA_INIT(&ad, IPC);
4736         ad.u.ipc_id = msq->q_perm.key;
4737
4738         return avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
4739                             MSGQ__ASSOCIATE, &ad);
4740 }
4741
4742 static int selinux_msg_queue_msgctl(struct msg_queue *msq, int cmd)
4743 {
4744         int err;
4745         int perms;
4746
4747         switch (cmd) {
4748         case IPC_INFO:
4749         case MSG_INFO:
4750                 /* No specific object, just general system-wide information. */
4751                 return task_has_system(current, SYSTEM__IPC_INFO);
4752         case IPC_STAT:
4753         case MSG_STAT:
4754                 perms = MSGQ__GETATTR | MSGQ__ASSOCIATE;
4755                 break;
4756         case IPC_SET:
4757                 perms = MSGQ__SETATTR;
4758                 break;
4759         case IPC_RMID:
4760                 perms = MSGQ__DESTROY;
4761                 break;
4762         default:
4763                 return 0;
4764         }
4765
4766         err = ipc_has_perm(&msq->q_perm, perms);
4767         return err;
4768 }
4769
4770 static int selinux_msg_queue_msgsnd(struct msg_queue *msq, struct msg_msg *msg, int msqflg)
4771 {
4772         struct ipc_security_struct *isec;
4773         struct msg_security_struct *msec;
4774         struct avc_audit_data ad;
4775         u32 sid = current_sid();
4776         int rc;
4777
4778         isec = msq->q_perm.security;
4779         msec = msg->security;
4780
4781         /*
4782          * First time through, need to assign label to the message
4783          */
4784         if (msec->sid == SECINITSID_UNLABELED) {
4785                 /*
4786                  * Compute new sid based on current process and
4787                  * message queue this message will be stored in
4788                  */
4789                 rc = security_transition_sid(sid, isec->sid, SECCLASS_MSG,
4790                                              &msec->sid);
4791                 if (rc)
4792                         return rc;
4793         }
4794
4795         AVC_AUDIT_DATA_INIT(&ad, IPC);
4796         ad.u.ipc_id = msq->q_perm.key;
4797
4798         /* Can this process write to the queue? */
4799         rc = avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
4800                           MSGQ__WRITE, &ad);
4801         if (!rc)
4802                 /* Can this process send the message */
4803                 rc = avc_has_perm(sid, msec->sid, SECCLASS_MSG,
4804                                   MSG__SEND, &ad);
4805         if (!rc)
4806                 /* Can the message be put in the queue? */
4807                 rc = avc_has_perm(msec->sid, isec->sid, SECCLASS_MSGQ,
4808                                   MSGQ__ENQUEUE, &ad);
4809
4810         return rc;
4811 }
4812
4813 static int selinux_msg_queue_msgrcv(struct msg_queue *msq, struct msg_msg *msg,
4814                                     struct task_struct *target,
4815                                     long type, int mode)
4816 {
4817         struct ipc_security_struct *isec;
4818         struct msg_security_struct *msec;
4819         struct avc_audit_data ad;
4820         u32 sid = task_sid(target);
4821         int rc;
4822
4823         isec = msq->q_perm.security;
4824         msec = msg->security;
4825
4826         AVC_AUDIT_DATA_INIT(&ad, IPC);
4827         ad.u.ipc_id = msq->q_perm.key;
4828
4829         rc = avc_has_perm(sid, isec->sid,
4830                           SECCLASS_MSGQ, MSGQ__READ, &ad);
4831         if (!rc)
4832                 rc = avc_has_perm(sid, msec->sid,
4833                                   SECCLASS_MSG, MSG__RECEIVE, &ad);
4834         return rc;
4835 }
4836
4837 /* Shared Memory security operations */
4838 static int selinux_shm_alloc_security(struct shmid_kernel *shp)
4839 {
4840         struct ipc_security_struct *isec;
4841         struct avc_audit_data ad;
4842         u32 sid = current_sid();
4843         int rc;
4844
4845         rc = ipc_alloc_security(current, &shp->shm_perm, SECCLASS_SHM);
4846         if (rc)
4847                 return rc;
4848
4849         isec = shp->shm_perm.security;
4850
4851         AVC_AUDIT_DATA_INIT(&ad, IPC);
4852         ad.u.ipc_id = shp->shm_perm.key;
4853
4854         rc = avc_has_perm(sid, isec->sid, SECCLASS_SHM,
4855                           SHM__CREATE, &ad);
4856         if (rc) {
4857                 ipc_free_security(&shp->shm_perm);
4858                 return rc;
4859         }
4860         return 0;
4861 }
4862
4863 static void selinux_shm_free_security(struct shmid_kernel *shp)
4864 {
4865         ipc_free_security(&shp->shm_perm);
4866 }
4867
4868 static int selinux_shm_associate(struct shmid_kernel *shp, int shmflg)
4869 {
4870         struct ipc_security_struct *isec;
4871         struct avc_audit_data ad;
4872         u32 sid = current_sid();
4873
4874         isec = shp->shm_perm.security;
4875
4876         AVC_AUDIT_DATA_INIT(&ad, IPC);
4877         ad.u.ipc_id = shp->shm_perm.key;
4878
4879         return avc_has_perm(sid, isec->sid, SECCLASS_SHM,
4880                             SHM__ASSOCIATE, &ad);
4881 }
4882
4883 /* Note, at this point, shp is locked down */
4884 static int selinux_shm_shmctl(struct shmid_kernel *shp, int cmd)
4885 {
4886         int perms;
4887         int err;
4888
4889         switch (cmd) {
4890         case IPC_INFO:
4891         case SHM_INFO:
4892                 /* No specific object, just general system-wide information. */
4893                 return task_has_system(current, SYSTEM__IPC_INFO);
4894         case IPC_STAT:
4895         case SHM_STAT:
4896                 perms = SHM__GETATTR | SHM__ASSOCIATE;
4897                 break;
4898         case IPC_SET:
4899                 perms = SHM__SETATTR;
4900                 break;
4901         case SHM_LOCK:
4902         case SHM_UNLOCK:
4903                 perms = SHM__LOCK;
4904                 break;
4905         case IPC_RMID:
4906                 perms = SHM__DESTROY;
4907                 break;
4908         default:
4909                 return 0;
4910         }
4911
4912         err = ipc_has_perm(&shp->shm_perm, perms);
4913         return err;
4914 }
4915
4916 static int selinux_shm_shmat(struct shmid_kernel *shp,
4917                              char __user *shmaddr, int shmflg)
4918 {
4919         u32 perms;
4920
4921         if (shmflg & SHM_RDONLY)
4922                 perms = SHM__READ;
4923         else
4924                 perms = SHM__READ | SHM__WRITE;
4925
4926         return ipc_has_perm(&shp->shm_perm, perms);
4927 }
4928
4929 /* Semaphore security operations */
4930 static int selinux_sem_alloc_security(struct sem_array *sma)
4931 {
4932         struct ipc_security_struct *isec;
4933         struct avc_audit_data ad;
4934         u32 sid = current_sid();
4935         int rc;
4936
4937         rc = ipc_alloc_security(current, &sma->sem_perm, SECCLASS_SEM);
4938         if (rc)
4939                 return rc;
4940
4941         isec = sma->sem_perm.security;
4942
4943         AVC_AUDIT_DATA_INIT(&ad, IPC);
4944         ad.u.ipc_id = sma->sem_perm.key;
4945
4946         rc = avc_has_perm(sid, isec->sid, SECCLASS_SEM,
4947                           SEM__CREATE, &ad);
4948         if (rc) {
4949                 ipc_free_security(&sma->sem_perm);
4950                 return rc;
4951         }
4952         return 0;
4953 }
4954
4955 static void selinux_sem_free_security(struct sem_array *sma)
4956 {
4957         ipc_free_security(&sma->sem_perm);
4958 }
4959
4960 static int selinux_sem_associate(struct sem_array *sma, int semflg)
4961 {
4962         struct ipc_security_struct *isec;
4963         struct avc_audit_data ad;
4964         u32 sid = current_sid();
4965
4966         isec = sma->sem_perm.security;
4967
4968         AVC_AUDIT_DATA_INIT(&ad, IPC);
4969         ad.u.ipc_id = sma->sem_perm.key;
4970
4971         return avc_has_perm(sid, isec->sid, SECCLASS_SEM,
4972                             SEM__ASSOCIATE, &ad);
4973 }
4974
4975 /* Note, at this point, sma is locked down */
4976 static int selinux_sem_semctl(struct sem_array *sma, int cmd)
4977 {
4978         int err;
4979         u32 perms;
4980
4981         switch (cmd) {
4982         case IPC_INFO:
4983         case SEM_INFO:
4984                 /* No specific object, just general system-wide information. */
4985                 return task_has_system(current, SYSTEM__IPC_INFO);
4986         case GETPID:
4987         case GETNCNT:
4988         case GETZCNT:
4989                 perms = SEM__GETATTR;
4990                 break;
4991         case GETVAL:
4992         case GETALL:
4993                 perms = SEM__READ;
4994                 break;
4995         case SETVAL:
4996         case SETALL:
4997                 perms = SEM__WRITE;
4998                 break;
4999         case IPC_RMID:
5000                 perms = SEM__DESTROY;
5001                 break;
5002         case IPC_SET:
5003                 perms = SEM__SETATTR;
5004                 break;
5005         case IPC_STAT:
5006         case SEM_STAT:
5007                 perms = SEM__GETATTR | SEM__ASSOCIATE;
5008                 break;
5009         default:
5010                 return 0;
5011         }
5012
5013         err = ipc_has_perm(&sma->sem_perm, perms);
5014         return err;
5015 }
5016
5017 static int selinux_sem_semop(struct sem_array *sma,
5018                              struct sembuf *sops, unsigned nsops, int alter)
5019 {
5020         u32 perms;
5021
5022         if (alter)
5023                 perms = SEM__READ | SEM__WRITE;
5024         else
5025                 perms = SEM__READ;
5026
5027         return ipc_has_perm(&sma->sem_perm, perms);
5028 }
5029
5030 static int selinux_ipc_permission(struct kern_ipc_perm *ipcp, short flag)
5031 {
5032         u32 av = 0;
5033
5034         av = 0;
5035         if (flag & S_IRUGO)
5036                 av |= IPC__UNIX_READ;
5037         if (flag & S_IWUGO)
5038                 av |= IPC__UNIX_WRITE;
5039
5040         if (av == 0)
5041                 return 0;
5042
5043         return ipc_has_perm(ipcp, av);
5044 }
5045
5046 static void selinux_ipc_getsecid(struct kern_ipc_perm *ipcp, u32 *secid)
5047 {
5048         struct ipc_security_struct *isec = ipcp->security;
5049         *secid = isec->sid;
5050 }
5051
5052 static void selinux_d_instantiate(struct dentry *dentry, struct inode *inode)
5053 {
5054         if (inode)
5055                 inode_doinit_with_dentry(inode, dentry);
5056 }
5057
5058 static int selinux_getprocattr(struct task_struct *p,
5059                                char *name, char **value)
5060 {
5061         const struct task_security_struct *__tsec;
5062         u32 sid;
5063         int error;
5064         unsigned len;
5065
5066         if (current != p) {
5067                 error = current_has_perm(p, PROCESS__GETATTR);
5068                 if (error)
5069                         return error;
5070         }
5071
5072         rcu_read_lock();
5073         __tsec = __task_cred(p)->security;
5074
5075         if (!strcmp(name, "current"))
5076                 sid = __tsec->sid;
5077         else if (!strcmp(name, "prev"))
5078                 sid = __tsec->osid;
5079         else if (!strcmp(name, "exec"))
5080                 sid = __tsec->exec_sid;
5081         else if (!strcmp(name, "fscreate"))
5082                 sid = __tsec->create_sid;
5083         else if (!strcmp(name, "keycreate"))
5084                 sid = __tsec->keycreate_sid;
5085         else if (!strcmp(name, "sockcreate"))
5086                 sid = __tsec->sockcreate_sid;
5087         else
5088                 goto invalid;
5089         rcu_read_unlock();
5090
5091         if (!sid)
5092                 return 0;
5093
5094         error = security_sid_to_context(sid, value, &len);
5095         if (error)
5096                 return error;
5097         return len;
5098
5099 invalid:
5100         rcu_read_unlock();
5101         return -EINVAL;
5102 }
5103
5104 static int selinux_setprocattr(struct task_struct *p,
5105                                char *name, void *value, size_t size)
5106 {
5107         struct task_security_struct *tsec;
5108         struct task_struct *tracer;
5109         struct cred *new;
5110         u32 sid = 0, ptsid;
5111         int error;
5112         char *str = value;
5113
5114         if (current != p) {
5115                 /* SELinux only allows a process to change its own
5116                    security attributes. */
5117                 return -EACCES;
5118         }
5119
5120         /*
5121          * Basic control over ability to set these attributes at all.
5122          * current == p, but we'll pass them separately in case the
5123          * above restriction is ever removed.
5124          */
5125         if (!strcmp(name, "exec"))
5126                 error = current_has_perm(p, PROCESS__SETEXEC);
5127         else if (!strcmp(name, "fscreate"))
5128                 error = current_has_perm(p, PROCESS__SETFSCREATE);
5129         else if (!strcmp(name, "keycreate"))
5130                 error = current_has_perm(p, PROCESS__SETKEYCREATE);
5131         else if (!strcmp(name, "sockcreate"))
5132                 error = current_has_perm(p, PROCESS__SETSOCKCREATE);
5133         else if (!strcmp(name, "current"))
5134                 error = current_has_perm(p, PROCESS__SETCURRENT);
5135         else
5136                 error = -EINVAL;
5137         if (error)
5138                 return error;
5139
5140         /* Obtain a SID for the context, if one was specified. */
5141         if (size && str[1] && str[1] != '\n') {
5142                 if (str[size-1] == '\n') {
5143                         str[size-1] = 0;
5144                         size--;
5145                 }
5146                 error = security_context_to_sid(value, size, &sid);
5147                 if (error == -EINVAL && !strcmp(name, "fscreate")) {
5148                         if (!capable(CAP_MAC_ADMIN))
5149                                 return error;
5150                         error = security_context_to_sid_force(value, size,
5151                                                               &sid);
5152                 }
5153                 if (error)
5154                         return error;
5155         }
5156
5157         new = prepare_creds();
5158         if (!new)
5159                 return -ENOMEM;
5160
5161         /* Permission checking based on the specified context is
5162            performed during the actual operation (execve,
5163            open/mkdir/...), when we know the full context of the
5164            operation.  See selinux_bprm_set_creds for the execve
5165            checks and may_create for the file creation checks. The
5166            operation will then fail if the context is not permitted. */
5167         tsec = new->security;
5168         if (!strcmp(name, "exec")) {
5169                 tsec->exec_sid = sid;
5170         } else if (!strcmp(name, "fscreate")) {
5171                 tsec->create_sid = sid;
5172         } else if (!strcmp(name, "keycreate")) {
5173                 error = may_create_key(sid, p);
5174                 if (error)
5175                         goto abort_change;
5176                 tsec->keycreate_sid = sid;
5177         } else if (!strcmp(name, "sockcreate")) {
5178                 tsec->sockcreate_sid = sid;
5179         } else if (!strcmp(name, "current")) {
5180                 error = -EINVAL;
5181                 if (sid == 0)
5182                         goto abort_change;
5183
5184                 /* Only allow single threaded processes to change context */
5185                 error = -EPERM;
5186                 if (!is_single_threaded(p)) {
5187                         error = security_bounded_transition(tsec->sid, sid);
5188                         if (error)
5189                                 goto abort_change;
5190                 }
5191
5192                 /* Check permissions for the transition. */
5193                 error = avc_has_perm(tsec->sid, sid, SECCLASS_PROCESS,
5194                                      PROCESS__DYNTRANSITION, NULL);
5195                 if (error)
5196                         goto abort_change;
5197
5198                 /* Check for ptracing, and update the task SID if ok.
5199                    Otherwise, leave SID unchanged and fail. */
5200                 ptsid = 0;
5201                 task_lock(p);
5202                 tracer = tracehook_tracer_task(p);
5203                 if (tracer)
5204                         ptsid = task_sid(tracer);
5205                 task_unlock(p);
5206
5207                 if (tracer) {
5208                         error = avc_has_perm(ptsid, sid, SECCLASS_PROCESS,
5209                                              PROCESS__PTRACE, NULL);
5210                         if (error)
5211                                 goto abort_change;
5212                 }
5213
5214                 tsec->sid = sid;
5215         } else {
5216                 error = -EINVAL;
5217                 goto abort_change;
5218         }
5219
5220         commit_creds(new);
5221         return size;
5222
5223 abort_change:
5224         abort_creds(new);
5225         return error;
5226 }
5227
5228 static int selinux_secid_to_secctx(u32 secid, char **secdata, u32 *seclen)
5229 {
5230         return security_sid_to_context(secid, secdata, seclen);
5231 }
5232
5233 static int selinux_secctx_to_secid(const char *secdata, u32 seclen, u32 *secid)
5234 {
5235         return security_context_to_sid(secdata, seclen, secid);
5236 }
5237
5238 static void selinux_release_secctx(char *secdata, u32 seclen)
5239 {
5240         kfree(secdata);
5241 }
5242
5243 #ifdef CONFIG_KEYS
5244
5245 static int selinux_key_alloc(struct key *k, const struct cred *cred,
5246                              unsigned long flags)
5247 {
5248         const struct task_security_struct *tsec;
5249         struct key_security_struct *ksec;
5250
5251         ksec = kzalloc(sizeof(struct key_security_struct), GFP_KERNEL);
5252         if (!ksec)
5253                 return -ENOMEM;
5254
5255         tsec = cred->security;
5256         if (tsec->keycreate_sid)
5257                 ksec->sid = tsec->keycreate_sid;
5258         else
5259                 ksec->sid = tsec->sid;
5260
5261         k->security = ksec;
5262         return 0;
5263 }
5264
5265 static void selinux_key_free(struct key *k)
5266 {
5267         struct key_security_struct *ksec = k->security;
5268
5269         k->security = NULL;
5270         kfree(ksec);
5271 }
5272
5273 static int selinux_key_permission(key_ref_t key_ref,
5274                                   const struct cred *cred,
5275                                   key_perm_t perm)
5276 {
5277         struct key *key;
5278         struct key_security_struct *ksec;
5279         u32 sid;
5280
5281         /* if no specific permissions are requested, we skip the
5282            permission check. No serious, additional covert channels
5283            appear to be created. */
5284         if (perm == 0)
5285                 return 0;
5286
5287         sid = cred_sid(cred);
5288
5289         key = key_ref_to_ptr(key_ref);
5290         ksec = key->security;
5291
5292         return avc_has_perm(sid, ksec->sid, SECCLASS_KEY, perm, NULL);
5293 }
5294
5295 static int selinux_key_getsecurity(struct key *key, char **_buffer)
5296 {
5297         struct key_security_struct *ksec = key->security;
5298         char *context = NULL;
5299         unsigned len;
5300         int rc;
5301
5302         rc = security_sid_to_context(ksec->sid, &context, &len);
5303         if (!rc)
5304                 rc = len;
5305         *_buffer = context;
5306         return rc;
5307 }
5308
5309 #endif
5310
5311 static struct security_operations selinux_ops = {
5312         .name =                         "selinux",
5313
5314         .ptrace_may_access =            selinux_ptrace_may_access,
5315         .ptrace_traceme =               selinux_ptrace_traceme,
5316         .capget =                       selinux_capget,
5317         .capset =                       selinux_capset,
5318         .sysctl =                       selinux_sysctl,
5319         .capable =                      selinux_capable,
5320         .quotactl =                     selinux_quotactl,
5321         .quota_on =                     selinux_quota_on,
5322         .syslog =                       selinux_syslog,
5323         .vm_enough_memory =             selinux_vm_enough_memory,
5324
5325         .netlink_send =                 selinux_netlink_send,
5326         .netlink_recv =                 selinux_netlink_recv,
5327
5328         .bprm_set_creds =               selinux_bprm_set_creds,
5329         .bprm_committing_creds =        selinux_bprm_committing_creds,
5330         .bprm_committed_creds =         selinux_bprm_committed_creds,
5331         .bprm_secureexec =              selinux_bprm_secureexec,
5332
5333         .sb_alloc_security =            selinux_sb_alloc_security,
5334         .sb_free_security =             selinux_sb_free_security,
5335         .sb_copy_data =                 selinux_sb_copy_data,
5336         .sb_kern_mount =                selinux_sb_kern_mount,
5337         .sb_show_options =              selinux_sb_show_options,
5338         .sb_statfs =                    selinux_sb_statfs,
5339         .sb_mount =                     selinux_mount,
5340         .sb_umount =                    selinux_umount,
5341         .sb_set_mnt_opts =              selinux_set_mnt_opts,
5342         .sb_clone_mnt_opts =            selinux_sb_clone_mnt_opts,
5343         .sb_parse_opts_str =            selinux_parse_opts_str,
5344
5345
5346         .inode_alloc_security =         selinux_inode_alloc_security,
5347         .inode_free_security =          selinux_inode_free_security,
5348         .inode_init_security =          selinux_inode_init_security,
5349         .inode_create =                 selinux_inode_create,
5350         .inode_link =                   selinux_inode_link,
5351         .inode_unlink =                 selinux_inode_unlink,
5352         .inode_symlink =                selinux_inode_symlink,
5353         .inode_mkdir =                  selinux_inode_mkdir,
5354         .inode_rmdir =                  selinux_inode_rmdir,
5355         .inode_mknod =                  selinux_inode_mknod,
5356         .inode_rename =                 selinux_inode_rename,
5357         .inode_readlink =               selinux_inode_readlink,
5358         .inode_follow_link =            selinux_inode_follow_link,
5359         .inode_permission =             selinux_inode_permission,
5360         .inode_setattr =                selinux_inode_setattr,
5361         .inode_getattr =                selinux_inode_getattr,
5362         .inode_setxattr =               selinux_inode_setxattr,
5363         .inode_post_setxattr =          selinux_inode_post_setxattr,
5364         .inode_getxattr =               selinux_inode_getxattr,
5365         .inode_listxattr =              selinux_inode_listxattr,
5366         .inode_removexattr =            selinux_inode_removexattr,
5367         .inode_getsecurity =            selinux_inode_getsecurity,
5368         .inode_setsecurity =            selinux_inode_setsecurity,
5369         .inode_listsecurity =           selinux_inode_listsecurity,
5370         .inode_getsecid =               selinux_inode_getsecid,
5371
5372         .file_permission =              selinux_file_permission,
5373         .file_alloc_security =          selinux_file_alloc_security,
5374         .file_free_security =           selinux_file_free_security,
5375         .file_ioctl =                   selinux_file_ioctl,
5376         .file_mmap =                    selinux_file_mmap,
5377         .file_mprotect =                selinux_file_mprotect,
5378         .file_lock =                    selinux_file_lock,
5379         .file_fcntl =                   selinux_file_fcntl,
5380         .file_set_fowner =              selinux_file_set_fowner,
5381         .file_send_sigiotask =          selinux_file_send_sigiotask,
5382         .file_receive =                 selinux_file_receive,
5383
5384         .dentry_open =                  selinux_dentry_open,
5385
5386         .task_create =                  selinux_task_create,
5387         .cred_free =                    selinux_cred_free,
5388         .cred_prepare =                 selinux_cred_prepare,
5389         .kernel_act_as =                selinux_kernel_act_as,
5390         .kernel_create_files_as =       selinux_kernel_create_files_as,
5391         .task_setpgid =                 selinux_task_setpgid,
5392         .task_getpgid =                 selinux_task_getpgid,
5393         .task_getsid =                  selinux_task_getsid,
5394         .task_getsecid =                selinux_task_getsecid,
5395         .task_setnice =                 selinux_task_setnice,
5396         .task_setioprio =               selinux_task_setioprio,
5397         .task_getioprio =               selinux_task_getioprio,
5398         .task_setrlimit =               selinux_task_setrlimit,
5399         .task_setscheduler =            selinux_task_setscheduler,
5400         .task_getscheduler =            selinux_task_getscheduler,
5401         .task_movememory =              selinux_task_movememory,
5402         .task_kill =                    selinux_task_kill,
5403         .task_wait =                    selinux_task_wait,
5404         .task_to_inode =                selinux_task_to_inode,
5405
5406         .ipc_permission =               selinux_ipc_permission,
5407         .ipc_getsecid =                 selinux_ipc_getsecid,
5408
5409         .msg_msg_alloc_security =       selinux_msg_msg_alloc_security,
5410         .msg_msg_free_security =        selinux_msg_msg_free_security,
5411
5412         .msg_queue_alloc_security =     selinux_msg_queue_alloc_security,
5413         .msg_queue_free_security =      selinux_msg_queue_free_security,
5414         .msg_queue_associate =          selinux_msg_queue_associate,
5415         .msg_queue_msgctl =             selinux_msg_queue_msgctl,
5416         .msg_queue_msgsnd =             selinux_msg_queue_msgsnd,
5417         .msg_queue_msgrcv =             selinux_msg_queue_msgrcv,
5418
5419         .shm_alloc_security =           selinux_shm_alloc_security,
5420         .shm_free_security =            selinux_shm_free_security,
5421         .shm_associate =                selinux_shm_associate,
5422         .shm_shmctl =                   selinux_shm_shmctl,
5423         .shm_shmat =                    selinux_shm_shmat,
5424
5425         .sem_alloc_security =           selinux_sem_alloc_security,
5426         .sem_free_security =            selinux_sem_free_security,
5427         .sem_associate =                selinux_sem_associate,
5428         .sem_semctl =                   selinux_sem_semctl,
5429         .sem_semop =                    selinux_sem_semop,
5430
5431         .d_instantiate =                selinux_d_instantiate,
5432
5433         .getprocattr =                  selinux_getprocattr,
5434         .setprocattr =                  selinux_setprocattr,
5435
5436         .secid_to_secctx =              selinux_secid_to_secctx,
5437         .secctx_to_secid =              selinux_secctx_to_secid,
5438         .release_secctx =               selinux_release_secctx,
5439
5440         .unix_stream_connect =          selinux_socket_unix_stream_connect,
5441         .unix_may_send =                selinux_socket_unix_may_send,
5442
5443         .socket_create =                selinux_socket_create,
5444         .socket_post_create =           selinux_socket_post_create,
5445         .socket_bind =                  selinux_socket_bind,
5446         .socket_connect =               selinux_socket_connect,
5447         .socket_listen =                selinux_socket_listen,
5448         .socket_accept =                selinux_socket_accept,
5449         .socket_sendmsg =               selinux_socket_sendmsg,
5450         .socket_recvmsg =               selinux_socket_recvmsg,
5451         .socket_getsockname =           selinux_socket_getsockname,
5452         .socket_getpeername =           selinux_socket_getpeername,
5453         .socket_getsockopt =            selinux_socket_getsockopt,
5454         .socket_setsockopt =            selinux_socket_setsockopt,
5455         .socket_shutdown =              selinux_socket_shutdown,
5456         .socket_sock_rcv_skb =          selinux_socket_sock_rcv_skb,
5457         .socket_getpeersec_stream =     selinux_socket_getpeersec_stream,
5458         .socket_getpeersec_dgram =      selinux_socket_getpeersec_dgram,
5459         .sk_alloc_security =            selinux_sk_alloc_security,
5460         .sk_free_security =             selinux_sk_free_security,
5461         .sk_clone_security =            selinux_sk_clone_security,
5462         .sk_getsecid =                  selinux_sk_getsecid,
5463         .sock_graft =                   selinux_sock_graft,
5464         .inet_conn_request =            selinux_inet_conn_request,
5465         .inet_csk_clone =               selinux_inet_csk_clone,
5466         .inet_conn_established =        selinux_inet_conn_established,
5467         .req_classify_flow =            selinux_req_classify_flow,
5468
5469 #ifdef CONFIG_SECURITY_NETWORK_XFRM
5470         .xfrm_policy_alloc_security =   selinux_xfrm_policy_alloc,
5471         .xfrm_policy_clone_security =   selinux_xfrm_policy_clone,
5472         .xfrm_policy_free_security =    selinux_xfrm_policy_free,
5473         .xfrm_policy_delete_security =  selinux_xfrm_policy_delete,
5474         .xfrm_state_alloc_security =    selinux_xfrm_state_alloc,
5475         .xfrm_state_free_security =     selinux_xfrm_state_free,
5476         .xfrm_state_delete_security =   selinux_xfrm_state_delete,
5477         .xfrm_policy_lookup =           selinux_xfrm_policy_lookup,
5478         .xfrm_state_pol_flow_match =    selinux_xfrm_state_pol_flow_match,
5479         .xfrm_decode_session =          selinux_xfrm_decode_session,
5480 #endif
5481
5482 #ifdef CONFIG_KEYS
5483         .key_alloc =                    selinux_key_alloc,
5484         .key_free =                     selinux_key_free,
5485         .key_permission =               selinux_key_permission,
5486         .key_getsecurity =              selinux_key_getsecurity,
5487 #endif
5488
5489 #ifdef CONFIG_AUDIT
5490         .audit_rule_init =              selinux_audit_rule_init,
5491         .audit_rule_known =             selinux_audit_rule_known,
5492         .audit_rule_match =             selinux_audit_rule_match,
5493         .audit_rule_free =              selinux_audit_rule_free,
5494 #endif
5495 };
5496
5497 static __init int selinux_init(void)
5498 {
5499         if (!security_module_enable(&selinux_ops)) {
5500                 selinux_enabled = 0;
5501                 return 0;
5502         }
5503
5504         if (!selinux_enabled) {
5505                 printk(KERN_INFO "SELinux:  Disabled at boot.\n");
5506                 return 0;
5507         }
5508
5509         printk(KERN_INFO "SELinux:  Initializing.\n");
5510
5511         /* Set the security state for the initial task. */
5512         cred_init_security();
5513
5514         sel_inode_cache = kmem_cache_create("selinux_inode_security",
5515                                             sizeof(struct inode_security_struct),
5516                                             0, SLAB_PANIC, NULL);
5517         avc_init();
5518
5519         secondary_ops = security_ops;
5520         if (!secondary_ops)
5521                 panic("SELinux: No initial security operations\n");
5522         if (register_security(&selinux_ops))
5523                 panic("SELinux: Unable to register with kernel.\n");
5524
5525         if (selinux_enforcing)
5526                 printk(KERN_DEBUG "SELinux:  Starting in enforcing mode\n");
5527         else
5528                 printk(KERN_DEBUG "SELinux:  Starting in permissive mode\n");
5529
5530         return 0;
5531 }
5532
5533 void selinux_complete_init(void)
5534 {
5535         printk(KERN_DEBUG "SELinux:  Completing initialization.\n");
5536
5537         /* Set up any superblocks initialized prior to the policy load. */
5538         printk(KERN_DEBUG "SELinux:  Setting up existing superblocks.\n");
5539         spin_lock(&sb_lock);
5540         spin_lock(&sb_security_lock);
5541 next_sb:
5542         if (!list_empty(&superblock_security_head)) {
5543                 struct superblock_security_struct *sbsec =
5544                                 list_entry(superblock_security_head.next,
5545                                            struct superblock_security_struct,
5546                                            list);
5547                 struct super_block *sb = sbsec->sb;
5548                 sb->s_count++;
5549                 spin_unlock(&sb_security_lock);
5550                 spin_unlock(&sb_lock);
5551                 down_read(&sb->s_umount);
5552                 if (sb->s_root)
5553                         superblock_doinit(sb, NULL);
5554                 drop_super(sb);
5555                 spin_lock(&sb_lock);
5556                 spin_lock(&sb_security_lock);
5557                 list_del_init(&sbsec->list);
5558                 goto next_sb;
5559         }
5560         spin_unlock(&sb_security_lock);
5561         spin_unlock(&sb_lock);
5562 }
5563
5564 /* SELinux requires early initialization in order to label
5565    all processes and objects when they are created. */
5566 security_initcall(selinux_init);
5567
5568 #if defined(CONFIG_NETFILTER)
5569
5570 static struct nf_hook_ops selinux_ipv4_ops[] = {
5571         {
5572                 .hook =         selinux_ipv4_postroute,
5573                 .owner =        THIS_MODULE,
5574                 .pf =           PF_INET,
5575                 .hooknum =      NF_INET_POST_ROUTING,
5576                 .priority =     NF_IP_PRI_SELINUX_LAST,
5577         },
5578         {
5579                 .hook =         selinux_ipv4_forward,
5580                 .owner =        THIS_MODULE,
5581                 .pf =           PF_INET,
5582                 .hooknum =      NF_INET_FORWARD,
5583                 .priority =     NF_IP_PRI_SELINUX_FIRST,
5584         },
5585         {
5586                 .hook =         selinux_ipv4_output,
5587                 .owner =        THIS_MODULE,
5588                 .pf =           PF_INET,
5589                 .hooknum =      NF_INET_LOCAL_OUT,
5590                 .priority =     NF_IP_PRI_SELINUX_FIRST,
5591         }
5592 };
5593
5594 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
5595
5596 static struct nf_hook_ops selinux_ipv6_ops[] = {
5597         {
5598                 .hook =         selinux_ipv6_postroute,
5599                 .owner =        THIS_MODULE,
5600                 .pf =           PF_INET6,
5601                 .hooknum =      NF_INET_POST_ROUTING,
5602                 .priority =     NF_IP6_PRI_SELINUX_LAST,
5603         },
5604         {
5605                 .hook =         selinux_ipv6_forward,
5606                 .owner =        THIS_MODULE,
5607                 .pf =           PF_INET6,
5608                 .hooknum =      NF_INET_FORWARD,
5609                 .priority =     NF_IP6_PRI_SELINUX_FIRST,
5610         }
5611 };
5612
5613 #endif  /* IPV6 */
5614
5615 static int __init selinux_nf_ip_init(void)
5616 {
5617         int err = 0;
5618
5619         if (!selinux_enabled)
5620                 goto out;
5621
5622         printk(KERN_DEBUG "SELinux:  Registering netfilter hooks\n");
5623
5624         err = nf_register_hooks(selinux_ipv4_ops, ARRAY_SIZE(selinux_ipv4_ops));
5625         if (err)
5626                 panic("SELinux: nf_register_hooks for IPv4: error %d\n", err);
5627
5628 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
5629         err = nf_register_hooks(selinux_ipv6_ops, ARRAY_SIZE(selinux_ipv6_ops));
5630         if (err)
5631                 panic("SELinux: nf_register_hooks for IPv6: error %d\n", err);
5632 #endif  /* IPV6 */
5633
5634 out:
5635         return err;
5636 }
5637
5638 __initcall(selinux_nf_ip_init);
5639
5640 #ifdef CONFIG_SECURITY_SELINUX_DISABLE
5641 static void selinux_nf_ip_exit(void)
5642 {
5643         printk(KERN_DEBUG "SELinux:  Unregistering netfilter hooks\n");
5644
5645         nf_unregister_hooks(selinux_ipv4_ops, ARRAY_SIZE(selinux_ipv4_ops));
5646 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
5647         nf_unregister_hooks(selinux_ipv6_ops, ARRAY_SIZE(selinux_ipv6_ops));
5648 #endif  /* IPV6 */
5649 }
5650 #endif
5651
5652 #else /* CONFIG_NETFILTER */
5653
5654 #ifdef CONFIG_SECURITY_SELINUX_DISABLE
5655 #define selinux_nf_ip_exit()
5656 #endif
5657
5658 #endif /* CONFIG_NETFILTER */
5659
5660 #ifdef CONFIG_SECURITY_SELINUX_DISABLE
5661 static int selinux_disabled;
5662
5663 int selinux_disable(void)
5664 {
5665         extern void exit_sel_fs(void);
5666
5667         if (ss_initialized) {
5668                 /* Not permitted after initial policy load. */
5669                 return -EINVAL;
5670         }
5671
5672         if (selinux_disabled) {
5673                 /* Only do this once. */
5674                 return -EINVAL;
5675         }
5676
5677         printk(KERN_INFO "SELinux:  Disabled at runtime.\n");
5678
5679         selinux_disabled = 1;
5680         selinux_enabled = 0;
5681
5682         /* Reset security_ops to the secondary module, dummy or capability. */
5683         security_ops = secondary_ops;
5684
5685         /* Unregister netfilter hooks. */
5686         selinux_nf_ip_exit();
5687
5688         /* Unregister selinuxfs. */
5689         exit_sel_fs();
5690
5691         return 0;
5692 }
5693 #endif