SAFE public projects git trees. - safe/jmp/linux-2.6/blob - security/selinux/hooks.c

   1 /*
   2  *  NSA Security-Enhanced Linux (SELinux) security module
   3  *
   4  *  This file contains the SELinux hook function implementations.
   5  *
   6  *  Authors:  Stephen Smalley, <sds@epoch.ncsc.mil>
   7  *            Chris Vance, <cvance@nai.com>
   8  *            Wayne Salamon, <wsalamon@nai.com>
   9  *            James Morris <jmorris@redhat.com>
  10  *
  11  *  Copyright (C) 2001,2002 Networks Associates Technology, Inc.
  12  *  Copyright (C) 2003-2008 Red Hat, Inc., James Morris <jmorris@redhat.com>
  13  *                                         Eric Paris <eparis@redhat.com>
  14  *  Copyright (C) 2004-2005 Trusted Computer Solutions, Inc.
  15  *                          <dgoeddel@trustedcs.com>
  16  *  Copyright (C) 2006, 2007 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 int selinux_compat_net;
  97 extern struct security_operations *security_ops;
  98
  99 /* SECMARK reference count */
 100 atomic_t selinux_secmark_refcount = ATOMIC_INIT(0);
 101
 102 #ifdef CONFIG_SECURITY_SELINUX_DEVELOP
 103 int selinux_enforcing;
 104
 105 static int __init enforcing_setup(char *str)
 106 {
 107         unsigned long enforcing;
 108         if (!strict_strtoul(str, 0, &enforcing))
 109                 selinux_enforcing = enforcing ? 1 : 0;
 110         return 1;
 111 }
 112 __setup("enforcing=", enforcing_setup);
 113 #endif
 114
 115 #ifdef CONFIG_SECURITY_SELINUX_BOOTPARAM
 116 int selinux_enabled = CONFIG_SECURITY_SELINUX_BOOTPARAM_VALUE;
 117
 118 static int __init selinux_enabled_setup(char *str)
 119 {
 120         unsigned long enabled;
 121         if (!strict_strtoul(str, 0, &enabled))
 122                 selinux_enabled = enabled ? 1 : 0;
 123         return 1;
 124 }
 125 __setup("selinux=", selinux_enabled_setup);
 126 #else
 127 int selinux_enabled = 1;
 128 #endif
 129
 130
 131 /*
 132  * Minimal support for a secondary security module,
 133  * just to allow the use of the capability module.
 134  */
 135 static struct security_operations *secondary_ops;
 136
 137 /* Lists of inode and superblock security structures initialized
 138    before the policy was loaded. */
 139 static LIST_HEAD(superblock_security_head);
 140 static DEFINE_SPINLOCK(sb_security_lock);
 141
 142 static struct kmem_cache *sel_inode_cache;
 143
 144 /**
 145  * selinux_secmark_enabled - Check to see if SECMARK is currently enabled
 146  *
 147  * Description:
 148  * This function checks the SECMARK reference counter to see if any SECMARK
 149  * targets are currently configured, if the reference counter is greater than
 150  * zero SECMARK is considered to be enabled.  Returns true (1) if SECMARK is
 151  * enabled, false (0) if SECMARK is disabled.
 152  *
 153  */
 154 static int selinux_secmark_enabled(void)
 155 {
 156         return (atomic_read(&selinux_secmark_refcount) > 0);
 157 }
 158
 159 /*
 160  * initialise the security for the init task
 161  */
 162 static void cred_init_security(void)
 163 {
 164         struct cred *cred = (struct cred *) current->real_cred;
 165         struct task_security_struct *tsec;
 166
 167         tsec = kzalloc(sizeof(struct task_security_struct), GFP_KERNEL);
 168         if (!tsec)
 169                 panic("SELinux:  Failed to initialize initial task.\n");
 170
 171         tsec->osid = tsec->sid = SECINITSID_KERNEL;
 172         cred->security = tsec;
 173 }
 174
 175 /*
 176  * get the security ID of a set of credentials
 177  */
 178 static inline u32 cred_sid(const struct cred *cred)
 179 {
 180         const struct task_security_struct *tsec;
 181
 182         tsec = cred->security;
 183         return tsec->sid;
 184 }
 185
 186 /*
 187  * get the objective security ID of a task
 188  */
 189 static inline u32 task_sid(const struct task_struct *task)
 190 {
 191         u32 sid;
 192
 193         rcu_read_lock();
 194         sid = cred_sid(__task_cred(task));
 195         rcu_read_unlock();
 196         return sid;
 197 }
 198
 199 /*
 200  * get the subjective security ID of the current task
 201  */
 202 static inline u32 current_sid(void)
 203 {
 204         const struct task_security_struct *tsec = current_cred()->security;
 205
 206         return tsec->sid;
 207 }
 208
 209 /* Allocate and free functions for each kind of security blob. */
 210
 211 static int inode_alloc_security(struct inode *inode)
 212 {
 213         struct inode_security_struct *isec;
 214         u32 sid = current_sid();
 215
 216         isec = kmem_cache_zalloc(sel_inode_cache, GFP_NOFS);
 217         if (!isec)
 218                 return -ENOMEM;
 219
 220         mutex_init(&isec->lock);
 221         INIT_LIST_HEAD(&isec->list);
 222         isec->inode = inode;
 223         isec->sid = SECINITSID_UNLABELED;
 224         isec->sclass = SECCLASS_FILE;
 225         isec->task_sid = sid;
 226         inode->i_security = isec;
 227
 228         return 0;
 229 }
 230
 231 static void inode_free_security(struct inode *inode)
 232 {
 233         struct inode_security_struct *isec = inode->i_security;
 234         struct superblock_security_struct *sbsec = inode->i_sb->s_security;
 235
 236         spin_lock(&sbsec->isec_lock);
 237         if (!list_empty(&isec->list))
 238                 list_del_init(&isec->list);
 239         spin_unlock(&sbsec->isec_lock);
 240
 241         inode->i_security = NULL;
 242         kmem_cache_free(sel_inode_cache, isec);
 243 }
 244
 245 static int file_alloc_security(struct file *file)
 246 {
 247         struct file_security_struct *fsec;
 248         u32 sid = current_sid();
 249
 250         fsec = kzalloc(sizeof(struct file_security_struct), GFP_KERNEL);
 251         if (!fsec)
 252                 return -ENOMEM;
 253
 254         fsec->sid = sid;
 255         fsec->fown_sid = sid;
 256         file->f_security = fsec;
 257
 258         return 0;
 259 }
 260
 261 static void file_free_security(struct file *file)
 262 {
 263         struct file_security_struct *fsec = file->f_security;
 264         file->f_security = NULL;
 265         kfree(fsec);
 266 }
 267
 268 static int superblock_alloc_security(struct super_block *sb)
 269 {
 270         struct superblock_security_struct *sbsec;
 271
 272         sbsec = kzalloc(sizeof(struct superblock_security_struct), GFP_KERNEL);
 273         if (!sbsec)
 274                 return -ENOMEM;
 275
 276         mutex_init(&sbsec->lock);
 277         INIT_LIST_HEAD(&sbsec->list);
 278         INIT_LIST_HEAD(&sbsec->isec_head);
 279         spin_lock_init(&sbsec->isec_lock);
 280         sbsec->sb = sb;
 281         sbsec->sid = SECINITSID_UNLABELED;
 282         sbsec->def_sid = SECINITSID_FILE;
 283         sbsec->mntpoint_sid = SECINITSID_UNLABELED;
 284         sb->s_security = sbsec;
 285
 286         return 0;
 287 }
 288
 289 static void superblock_free_security(struct super_block *sb)
 290 {
 291         struct superblock_security_struct *sbsec = sb->s_security;
 292
 293         spin_lock(&sb_security_lock);
 294         if (!list_empty(&sbsec->list))
 295                 list_del_init(&sbsec->list);
 296         spin_unlock(&sb_security_lock);
 297
 298         sb->s_security = NULL;
 299         kfree(sbsec);
 300 }
 301
 302 static int sk_alloc_security(struct sock *sk, int family, gfp_t priority)
 303 {
 304         struct sk_security_struct *ssec;
 305
 306         ssec = kzalloc(sizeof(*ssec), priority);
 307         if (!ssec)
 308                 return -ENOMEM;
 309
 310         ssec->peer_sid = SECINITSID_UNLABELED;
 311         ssec->sid = SECINITSID_UNLABELED;
 312         sk->sk_security = ssec;
 313
 314         selinux_netlbl_sk_security_reset(ssec, family);
 315
 316         return 0;
 317 }
 318
 319 static void sk_free_security(struct sock *sk)
 320 {
 321         struct sk_security_struct *ssec = sk->sk_security;
 322
 323         sk->sk_security = NULL;
 324         selinux_netlbl_sk_security_free(ssec);
 325         kfree(ssec);
 326 }
 327
 328 /* The security server must be initialized before
 329    any labeling or access decisions can be provided. */
 330 extern int ss_initialized;
 331
 332 /* The file system's label must be initialized prior to use. */
 333
 334 static char *labeling_behaviors[6] = {
 335         "uses xattr",
 336         "uses transition SIDs",
 337         "uses task SIDs",
 338         "uses genfs_contexts",
 339         "not configured for labeling",
 340         "uses mountpoint labeling",
 341 };
 342
 343 static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dentry);
 344
 345 static inline int inode_doinit(struct inode *inode)
 346 {
 347         return inode_doinit_with_dentry(inode, NULL);
 348 }
 349
 350 enum {
 351         Opt_error = -1,
 352         Opt_context = 1,
 353         Opt_fscontext = 2,
 354         Opt_defcontext = 3,
 355         Opt_rootcontext = 4,
 356         Opt_labelsupport = 5,
 357 };
 358
 359 static const match_table_t tokens = {
 360         {Opt_context, CONTEXT_STR "%s"},
 361         {Opt_fscontext, FSCONTEXT_STR "%s"},
 362         {Opt_defcontext, DEFCONTEXT_STR "%s"},
 363         {Opt_rootcontext, ROOTCONTEXT_STR "%s"},
 364         {Opt_labelsupport, LABELSUPP_STR},
 365         {Opt_error, NULL},
 366 };
 367
 368 #define SEL_MOUNT_FAIL_MSG "SELinux:  duplicate or incompatible mount options\n"
 369
 370 static int may_context_mount_sb_relabel(u32 sid,
 371                         struct superblock_security_struct *sbsec,
 372                         const struct cred *cred)
 373 {
 374         const struct task_security_struct *tsec = cred->security;
 375         int rc;
 376
 377         rc = avc_has_perm(tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM,
 378                           FILESYSTEM__RELABELFROM, NULL);
 379         if (rc)
 380                 return rc;
 381
 382         rc = avc_has_perm(tsec->sid, sid, SECCLASS_FILESYSTEM,
 383                           FILESYSTEM__RELABELTO, NULL);
 384         return rc;
 385 }
 386
 387 static int may_context_mount_inode_relabel(u32 sid,
 388                         struct superblock_security_struct *sbsec,
 389                         const struct cred *cred)
 390 {
 391         const struct task_security_struct *tsec = cred->security;
 392         int rc;
 393         rc = avc_has_perm(tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM,
 394                           FILESYSTEM__RELABELFROM, NULL);
 395         if (rc)
 396                 return rc;
 397
 398         rc = avc_has_perm(sid, sbsec->sid, SECCLASS_FILESYSTEM,
 399                           FILESYSTEM__ASSOCIATE, NULL);
 400         return rc;
 401 }
 402
 403 static int sb_finish_set_opts(struct super_block *sb)
 404 {
 405         struct superblock_security_struct *sbsec = sb->s_security;
 406         struct dentry *root = sb->s_root;
 407         struct inode *root_inode = root->d_inode;
 408         int rc = 0;
 409
 410         if (sbsec->behavior == SECURITY_FS_USE_XATTR) {
 411                 /* Make sure that the xattr handler exists and that no
 412                    error other than -ENODATA is returned by getxattr on
 413                    the root directory.  -ENODATA is ok, as this may be
 414                    the first boot of the SELinux kernel before we have
 415                    assigned xattr values to the filesystem. */
 416                 if (!root_inode->i_op->getxattr) {
 417                         printk(KERN_WARNING "SELinux: (dev %s, type %s) has no "
 418                                "xattr support\n", sb->s_id, sb->s_type->name);
 419                         rc = -EOPNOTSUPP;
 420                         goto out;
 421                 }
 422                 rc = root_inode->i_op->getxattr(root, XATTR_NAME_SELINUX, NULL, 0);
 423                 if (rc < 0 && rc != -ENODATA) {
 424                         if (rc == -EOPNOTSUPP)
 425                                 printk(KERN_WARNING "SELinux: (dev %s, type "
 426                                        "%s) has no security xattr handler\n",
 427                                        sb->s_id, sb->s_type->name);
 428                         else
 429                                 printk(KERN_WARNING "SELinux: (dev %s, type "
 430                                        "%s) getxattr errno %d\n", sb->s_id,
 431                                        sb->s_type->name, -rc);
 432                         goto out;
 433                 }
 434         }
 435
 436         sbsec->flags |= (SE_SBINITIALIZED | SE_SBLABELSUPP);
 437
 438         if (sbsec->behavior > ARRAY_SIZE(labeling_behaviors))
 439                 printk(KERN_ERR "SELinux: initialized (dev %s, type %s), unknown behavior\n",
 440                        sb->s_id, sb->s_type->name);
 441         else
 442                 printk(KERN_DEBUG "SELinux: initialized (dev %s, type %s), %s\n",
 443                        sb->s_id, sb->s_type->name,
 444                        labeling_behaviors[sbsec->behavior-1]);
 445
 446         if (sbsec->behavior == SECURITY_FS_USE_GENFS ||
 447             sbsec->behavior == SECURITY_FS_USE_MNTPOINT ||
 448             sbsec->behavior == SECURITY_FS_USE_NONE ||
 449             sbsec->behavior > ARRAY_SIZE(labeling_behaviors))
 450                 sbsec->flags &= ~SE_SBLABELSUPP;
 451
 452         /* Initialize the root inode. */
 453         rc = inode_doinit_with_dentry(root_inode, root);
 454
 455         /* Initialize any other inodes associated with the superblock, e.g.
 456            inodes created prior to initial policy load or inodes created
 457            during get_sb by a pseudo filesystem that directly
 458            populates itself. */
 459         spin_lock(&sbsec->isec_lock);
 460 next_inode:
 461         if (!list_empty(&sbsec->isec_head)) {
 462                 struct inode_security_struct *isec =
 463                                 list_entry(sbsec->isec_head.next,
 464                                            struct inode_security_struct, list);
 465                 struct inode *inode = isec->inode;
 466                 spin_unlock(&sbsec->isec_lock);
 467                 inode = igrab(inode);
 468                 if (inode) {
 469                         if (!IS_PRIVATE(inode))
 470                                 inode_doinit(inode);
 471                         iput(inode);
 472                 }
 473                 spin_lock(&sbsec->isec_lock);
 474                 list_del_init(&isec->list);
 475                 goto next_inode;
 476         }
 477         spin_unlock(&sbsec->isec_lock);
 478 out:
 479         return rc;
 480 }
 481
 482 /*
 483  * This function should allow an FS to ask what it's mount security
 484  * options were so it can use those later for submounts, displaying
 485  * mount options, or whatever.
 486  */
 487 static int selinux_get_mnt_opts(const struct super_block *sb,
 488                                 struct security_mnt_opts *opts)
 489 {
 490         int rc = 0, i;
 491         struct superblock_security_struct *sbsec = sb->s_security;
 492         char *context = NULL;
 493         u32 len;
 494         char tmp;
 495
 496         security_init_mnt_opts(opts);
 497
 498         if (!(sbsec->flags & SE_SBINITIALIZED))
 499                 return -EINVAL;
 500
 501         if (!ss_initialized)
 502                 return -EINVAL;
 503
 504         tmp = sbsec->flags & SE_MNTMASK;
 505         /* count the number of mount options for this sb */
 506         for (i = 0; i < 8; i++) {
 507                 if (tmp & 0x01)
 508                         opts->num_mnt_opts++;
 509                 tmp >>= 1;
 510         }
 511         /* Check if the Label support flag is set */
 512         if (sbsec->flags & SE_SBLABELSUPP)
 513                 opts->num_mnt_opts++;
 514
 515         opts->mnt_opts = kcalloc(opts->num_mnt_opts, sizeof(char *), GFP_ATOMIC);
 516         if (!opts->mnt_opts) {
 517                 rc = -ENOMEM;
 518                 goto out_free;
 519         }
 520
 521         opts->mnt_opts_flags = kcalloc(opts->num_mnt_opts, sizeof(int), GFP_ATOMIC);
 522         if (!opts->mnt_opts_flags) {
 523                 rc = -ENOMEM;
 524                 goto out_free;
 525         }
 526
 527         i = 0;
 528         if (sbsec->flags & FSCONTEXT_MNT) {
 529                 rc = security_sid_to_context(sbsec->sid, &context, &len);
 530                 if (rc)
 531                         goto out_free;
 532                 opts->mnt_opts[i] = context;
 533                 opts->mnt_opts_flags[i++] = FSCONTEXT_MNT;
 534         }
 535         if (sbsec->flags & CONTEXT_MNT) {
 536                 rc = security_sid_to_context(sbsec->mntpoint_sid, &context, &len);
 537                 if (rc)
 538                         goto out_free;
 539                 opts->mnt_opts[i] = context;
 540                 opts->mnt_opts_flags[i++] = CONTEXT_MNT;
 541         }
 542         if (sbsec->flags & DEFCONTEXT_MNT) {
 543                 rc = security_sid_to_context(sbsec->def_sid, &context, &len);
 544                 if (rc)
 545                         goto out_free;
 546                 opts->mnt_opts[i] = context;
 547                 opts->mnt_opts_flags[i++] = DEFCONTEXT_MNT;
 548         }
 549         if (sbsec->flags & ROOTCONTEXT_MNT) {
 550                 struct inode *root = sbsec->sb->s_root->d_inode;
 551                 struct inode_security_struct *isec = root->i_security;
 552
 553                 rc = security_sid_to_context(isec->sid, &context, &len);
 554                 if (rc)
 555                         goto out_free;
 556                 opts->mnt_opts[i] = context;
 557                 opts->mnt_opts_flags[i++] = ROOTCONTEXT_MNT;
 558         }
 559         if (sbsec->flags & SE_SBLABELSUPP) {
 560                 opts->mnt_opts[i] = NULL;
 561                 opts->mnt_opts_flags[i++] = SE_SBLABELSUPP;
 562         }
 563
 564         BUG_ON(i != opts->num_mnt_opts);
 565
 566         return 0;
 567
 568 out_free:
 569         security_free_mnt_opts(opts);
 570         return rc;
 571 }
 572
 573 static int bad_option(struct superblock_security_struct *sbsec, char flag,
 574                       u32 old_sid, u32 new_sid)
 575 {
 576         char mnt_flags = sbsec->flags & SE_MNTMASK;
 577
 578         /* check if the old mount command had the same options */
 579         if (sbsec->flags & SE_SBINITIALIZED)
 580                 if (!(sbsec->flags & flag) ||
 581                     (old_sid != new_sid))
 582                         return 1;
 583
 584         /* check if we were passed the same options twice,
 585          * aka someone passed context=a,context=b
 586          */
 587         if (!(sbsec->flags & SE_SBINITIALIZED))
 588                 if (mnt_flags & flag)
 589                         return 1;
 590         return 0;
 591 }
 592
 593 /*
 594  * Allow filesystems with binary mount data to explicitly set mount point
 595  * labeling information.
 596  */
 597 static int selinux_set_mnt_opts(struct super_block *sb,
 598                                 struct security_mnt_opts *opts)
 599 {
 600         const struct cred *cred = current_cred();
 601         int rc = 0, i;
 602         struct superblock_security_struct *sbsec = sb->s_security;
 603         const char *name = sb->s_type->name;
 604         struct inode *inode = sbsec->sb->s_root->d_inode;
 605         struct inode_security_struct *root_isec = inode->i_security;
 606         u32 fscontext_sid = 0, context_sid = 0, rootcontext_sid = 0;
 607         u32 defcontext_sid = 0;
 608         char **mount_options = opts->mnt_opts;
 609         int *flags = opts->mnt_opts_flags;
 610         int num_opts = opts->num_mnt_opts;
 611
 612         mutex_lock(&sbsec->lock);
 613
 614         if (!ss_initialized) {
 615                 if (!num_opts) {
 616                         /* Defer initialization until selinux_complete_init,
 617                            after the initial policy is loaded and the security
 618                            server is ready to handle calls. */
 619                         spin_lock(&sb_security_lock);
 620                         if (list_empty(&sbsec->list))
 621                                 list_add(&sbsec->list, &superblock_security_head);
 622                         spin_unlock(&sb_security_lock);
 623                         goto out;
 624                 }
 625                 rc = -EINVAL;
 626                 printk(KERN_WARNING "SELinux: Unable to set superblock options "
 627                         "before the security server is initialized\n");
 628                 goto out;
 629         }
 630
 631         /*
 632          * Binary mount data FS will come through this function twice.  Once
 633          * from an explicit call and once from the generic calls from the vfs.
 634          * Since the generic VFS calls will not contain any security mount data
 635          * we need to skip the double mount verification.
 636          *
 637          * This does open a hole in which we will not notice if the first
 638          * mount using this sb set explict options and a second mount using
 639          * this sb does not set any security options.  (The first options
 640          * will be used for both mounts)
 641          */
 642         if ((sbsec->flags & SE_SBINITIALIZED) && (sb->s_type->fs_flags & FS_BINARY_MOUNTDATA)
 643             && (num_opts == 0))
 644                 goto out;
 645
 646         /*
 647          * parse the mount options, check if they are valid sids.
 648          * also check if someone is trying to mount the same sb more
 649          * than once with different security options.
 650          */
 651         for (i = 0; i < num_opts; i++) {
 652                 u32 sid;
 653
 654                 if (flags[i] == SE_SBLABELSUPP)
 655                         continue;
 656                 rc = security_context_to_sid(mount_options[i],
 657                                              strlen(mount_options[i]), &sid);
 658                 if (rc) {
 659                         printk(KERN_WARNING "SELinux: security_context_to_sid"
 660                                "(%s) failed for (dev %s, type %s) errno=%d\n",
 661                                mount_options[i], sb->s_id, name, rc);
 662                         goto out;
 663                 }
 664                 switch (flags[i]) {
 665                 case FSCONTEXT_MNT:
 666                         fscontext_sid = sid;
 667
 668                         if (bad_option(sbsec, FSCONTEXT_MNT, sbsec->sid,
 669                                         fscontext_sid))
 670                                 goto out_double_mount;
 671
 672                         sbsec->flags |= FSCONTEXT_MNT;
 673                         break;
 674                 case CONTEXT_MNT:
 675                         context_sid = sid;
 676
 677                         if (bad_option(sbsec, CONTEXT_MNT, sbsec->mntpoint_sid,
 678                                         context_sid))
 679                                 goto out_double_mount;
 680
 681                         sbsec->flags |= CONTEXT_MNT;
 682                         break;
 683                 case ROOTCONTEXT_MNT:
 684                         rootcontext_sid = sid;
 685
 686                         if (bad_option(sbsec, ROOTCONTEXT_MNT, root_isec->sid,
 687                                         rootcontext_sid))
 688                                 goto out_double_mount;
 689
 690                         sbsec->flags |= ROOTCONTEXT_MNT;
 691
 692                         break;
 693                 case DEFCONTEXT_MNT:
 694                         defcontext_sid = sid;
 695
 696                         if (bad_option(sbsec, DEFCONTEXT_MNT, sbsec->def_sid,
 697                                         defcontext_sid))
 698                                 goto out_double_mount;
 699
 700                         sbsec->flags |= DEFCONTEXT_MNT;
 701
 702                         break;
 703                 default:
 704                         rc = -EINVAL;
 705                         goto out;
 706                 }
 707         }
 708
 709         if (sbsec->flags & SE_SBINITIALIZED) {
 710                 /* previously mounted with options, but not on this attempt? */
 711                 if ((sbsec->flags & SE_MNTMASK) && !num_opts)
 712                         goto out_double_mount;
 713                 rc = 0;
 714                 goto out;
 715         }
 716
 717         if (strcmp(sb->s_type->name, "proc") == 0)
 718                 sbsec->flags |= SE_SBPROC;
 719
 720         /* Determine the labeling behavior to use for this filesystem type. */
 721         rc = security_fs_use((sbsec->flags & SE_SBPROC) ? "proc" : sb->s_type->name, &sbsec->behavior, &sbsec->sid);
 722         if (rc) {
 723                 printk(KERN_WARNING "%s: security_fs_use(%s) returned %d\n",
 724                        __func__, sb->s_type->name, rc);
 725                 goto out;
 726         }
 727
 728         /* sets the context of the superblock for the fs being mounted. */
 729         if (fscontext_sid) {
 730                 rc = may_context_mount_sb_relabel(fscontext_sid, sbsec, cred);
 731                 if (rc)
 732                         goto out;
 733
 734                 sbsec->sid = fscontext_sid;
 735         }
 736
 737         /*
 738          * Switch to using mount point labeling behavior.
 739          * sets the label used on all file below the mountpoint, and will set
 740          * the superblock context if not already set.
 741          */
 742         if (context_sid) {
 743                 if (!fscontext_sid) {
 744                         rc = may_context_mount_sb_relabel(context_sid, sbsec,
 745                                                           cred);
 746                         if (rc)
 747                                 goto out;
 748                         sbsec->sid = context_sid;
 749                 } else {
 750                         rc = may_context_mount_inode_relabel(context_sid, sbsec,
 751                                                              cred);
 752                         if (rc)
 753                                 goto out;
 754                 }
 755                 if (!rootcontext_sid)
 756                         rootcontext_sid = context_sid;
 757
 758                 sbsec->mntpoint_sid = context_sid;
 759                 sbsec->behavior = SECURITY_FS_USE_MNTPOINT;
 760         }
 761
 762         if (rootcontext_sid) {
 763                 rc = may_context_mount_inode_relabel(rootcontext_sid, sbsec,
 764                                                      cred);
 765                 if (rc)
 766                         goto out;
 767
 768                 root_isec->sid = rootcontext_sid;
 769                 root_isec->initialized = 1;
 770         }
 771
 772         if (defcontext_sid) {
 773                 if (sbsec->behavior != SECURITY_FS_USE_XATTR) {
 774                         rc = -EINVAL;
 775                         printk(KERN_WARNING "SELinux: defcontext option is "
 776                                "invalid for this filesystem type\n");
 777                         goto out;
 778                 }
 779
 780                 if (defcontext_sid != sbsec->def_sid) {
 781                         rc = may_context_mount_inode_relabel(defcontext_sid,
 782                                                              sbsec, cred);
 783                         if (rc)
 784                                 goto out;
 785                 }
 786
 787                 sbsec->def_sid = defcontext_sid;
 788         }
 789
 790         rc = sb_finish_set_opts(sb);
 791 out:
 792         mutex_unlock(&sbsec->lock);
 793         return rc;
 794 out_double_mount:
 795         rc = -EINVAL;
 796         printk(KERN_WARNING "SELinux: mount invalid.  Same superblock, different "
 797                "security settings for (dev %s, type %s)\n", sb->s_id, name);
 798         goto out;
 799 }
 800
 801 static void selinux_sb_clone_mnt_opts(const struct super_block *oldsb,
 802                                         struct super_block *newsb)
 803 {
 804         const struct superblock_security_struct *oldsbsec = oldsb->s_security;
 805         struct superblock_security_struct *newsbsec = newsb->s_security;
 806
 807         int set_fscontext =     (oldsbsec->flags & FSCONTEXT_MNT);
 808         int set_context =       (oldsbsec->flags & CONTEXT_MNT);
 809         int set_rootcontext =   (oldsbsec->flags & ROOTCONTEXT_MNT);
 810
 811         /*
 812          * if the parent was able to be mounted it clearly had no special lsm
 813          * mount options.  thus we can safely put this sb on the list and deal
 814          * with it later
 815          */
 816         if (!ss_initialized) {
 817                 spin_lock(&sb_security_lock);
 818                 if (list_empty(&newsbsec->list))
 819                         list_add(&newsbsec->list, &superblock_security_head);
 820                 spin_unlock(&sb_security_lock);
 821                 return;
 822         }
 823
 824         /* how can we clone if the old one wasn't set up?? */
 825         BUG_ON(!(oldsbsec->flags & SE_SBINITIALIZED));
 826
 827         /* if fs is reusing a sb, just let its options stand... */
 828         if (newsbsec->flags & SE_SBINITIALIZED)
 829                 return;
 830
 831         mutex_lock(&newsbsec->lock);
 832
 833         newsbsec->flags = oldsbsec->flags;
 834
 835         newsbsec->sid = oldsbsec->sid;
 836         newsbsec->def_sid = oldsbsec->def_sid;
 837         newsbsec->behavior = oldsbsec->behavior;
 838
 839         if (set_context) {
 840                 u32 sid = oldsbsec->mntpoint_sid;
 841
 842                 if (!set_fscontext)
 843                         newsbsec->sid = sid;
 844                 if (!set_rootcontext) {
 845                         struct inode *newinode = newsb->s_root->d_inode;
 846                         struct inode_security_struct *newisec = newinode->i_security;
 847                         newisec->sid = sid;
 848                 }
 849                 newsbsec->mntpoint_sid = sid;
 850         }
 851         if (set_rootcontext) {
 852                 const struct inode *oldinode = oldsb->s_root->d_inode;
 853                 const struct inode_security_struct *oldisec = oldinode->i_security;
 854                 struct inode *newinode = newsb->s_root->d_inode;
 855                 struct inode_security_struct *newisec = newinode->i_security;
 856
 857                 newisec->sid = oldisec->sid;
 858         }
 859
 860         sb_finish_set_opts(newsb);
 861         mutex_unlock(&newsbsec->lock);
 862 }
 863
 864 static int selinux_parse_opts_str(char *options,
 865                                   struct security_mnt_opts *opts)
 866 {
 867         char *p;
 868         char *context = NULL, *defcontext = NULL;
 869         char *fscontext = NULL, *rootcontext = NULL;
 870         int rc, num_mnt_opts = 0;
 871
 872         opts->num_mnt_opts = 0;
 873
 874         /* Standard string-based options. */
 875         while ((p = strsep(&options, "|")) != NULL) {
 876                 int token;
 877                 substring_t args[MAX_OPT_ARGS];
 878
 879                 if (!*p)
 880                         continue;
 881
 882                 token = match_token(p, tokens, args);
 883
 884                 switch (token) {
 885                 case Opt_context:
 886                         if (context || defcontext) {
 887                                 rc = -EINVAL;
 888                                 printk(KERN_WARNING SEL_MOUNT_FAIL_MSG);
 889                                 goto out_err;
 890                         }
 891                         context = match_strdup(&args[0]);
 892                         if (!context) {
 893                                 rc = -ENOMEM;
 894                                 goto out_err;
 895                         }
 896                         break;
 897
 898                 case Opt_fscontext:
 899                         if (fscontext) {
 900                                 rc = -EINVAL;
 901                                 printk(KERN_WARNING SEL_MOUNT_FAIL_MSG);
 902                                 goto out_err;
 903                         }
 904                         fscontext = match_strdup(&args[0]);
 905                         if (!fscontext) {
 906                                 rc = -ENOMEM;
 907                                 goto out_err;
 908                         }
 909                         break;
 910
 911                 case Opt_rootcontext:
 912                         if (rootcontext) {
 913                                 rc = -EINVAL;
 914                                 printk(KERN_WARNING SEL_MOUNT_FAIL_MSG);
 915                                 goto out_err;
 916                         }
 917                         rootcontext = match_strdup(&args[0]);
 918                         if (!rootcontext) {
 919                                 rc = -ENOMEM;
 920                                 goto out_err;
 921                         }
 922                         break;
 923
 924                 case Opt_defcontext:
 925                         if (context || defcontext) {
 926                                 rc = -EINVAL;
 927                                 printk(KERN_WARNING SEL_MOUNT_FAIL_MSG);
 928                                 goto out_err;
 929                         }
 930                         defcontext = match_strdup(&args[0]);
 931                         if (!defcontext) {
 932                                 rc = -ENOMEM;
 933                                 goto out_err;
 934                         }
 935                         break;
 936                 case Opt_labelsupport:
 937                         break;
 938                 default:
 939                         rc = -EINVAL;
 940                         printk(KERN_WARNING "SELinux:  unknown mount option\n");
 941                         goto out_err;
 942
 943                 }
 944         }
 945
 946         rc = -ENOMEM;
 947         opts->mnt_opts = kcalloc(NUM_SEL_MNT_OPTS, sizeof(char *), GFP_ATOMIC);
 948         if (!opts->mnt_opts)
 949                 goto out_err;
 950
 951         opts->mnt_opts_flags = kcalloc(NUM_SEL_MNT_OPTS, sizeof(int), GFP_ATOMIC);
 952         if (!opts->mnt_opts_flags) {
 953                 kfree(opts->mnt_opts);
 954                 goto out_err;
 955         }
 956
 957         if (fscontext) {
 958                 opts->mnt_opts[num_mnt_opts] = fscontext;
 959                 opts->mnt_opts_flags[num_mnt_opts++] = FSCONTEXT_MNT;
 960         }
 961         if (context) {
 962                 opts->mnt_opts[num_mnt_opts] = context;
 963                 opts->mnt_opts_flags[num_mnt_opts++] = CONTEXT_MNT;
 964         }
 965         if (rootcontext) {
 966                 opts->mnt_opts[num_mnt_opts] = rootcontext;
 967                 opts->mnt_opts_flags[num_mnt_opts++] = ROOTCONTEXT_MNT;
 968         }
 969         if (defcontext) {
 970                 opts->mnt_opts[num_mnt_opts] = defcontext;
 971                 opts->mnt_opts_flags[num_mnt_opts++] = DEFCONTEXT_MNT;
 972         }
 973
 974         opts->num_mnt_opts = num_mnt_opts;
 975         return 0;
 976
 977 out_err:
 978         kfree(context);
 979         kfree(defcontext);
 980         kfree(fscontext);
 981         kfree(rootcontext);
 982         return rc;
 983 }
 984 /*
 985  * string mount options parsing and call set the sbsec
 986  */
 987 static int superblock_doinit(struct super_block *sb, void *data)
 988 {
 989         int rc = 0;
 990         char *options = data;
 991         struct security_mnt_opts opts;
 992
 993         security_init_mnt_opts(&opts);
 994
 995         if (!data)
 996                 goto out;
 997
 998         BUG_ON(sb->s_type->fs_flags & FS_BINARY_MOUNTDATA);
 999
1000         rc = selinux_parse_opts_str(options, &opts);
1001         if (rc)
1002                 goto out_err;
1003
1004 out:
1005         rc = selinux_set_mnt_opts(sb, &opts);
1006
1007 out_err:
1008         security_free_mnt_opts(&opts);
1009         return rc;
1010 }
1011
1012 static void selinux_write_opts(struct seq_file *m,
1013                                struct security_mnt_opts *opts)
1014 {
1015         int i;
1016         char *prefix;
1017
1018         for (i = 0; i < opts->num_mnt_opts; i++) {
1019                 char *has_comma;
1020
1021                 if (opts->mnt_opts[i])
1022                         has_comma = strchr(opts->mnt_opts[i], ',');
1023                 else
1024                         has_comma = NULL;
1025
1026                 switch (opts->mnt_opts_flags[i]) {
1027                 case CONTEXT_MNT:
1028                         prefix = CONTEXT_STR;
1029                         break;
1030                 case FSCONTEXT_MNT:
1031                         prefix = FSCONTEXT_STR;
1032                         break;
1033                 case ROOTCONTEXT_MNT:
1034                         prefix = ROOTCONTEXT_STR;
1035                         break;
1036                 case DEFCONTEXT_MNT:
1037                         prefix = DEFCONTEXT_STR;
1038                         break;
1039                 case SE_SBLABELSUPP:
1040                         seq_putc(m, ',');
1041                         seq_puts(m, LABELSUPP_STR);
1042                         continue;
1043                 default:
1044                         BUG();
1045                 };
1046                 /* we need a comma before each option */
1047                 seq_putc(m, ',');
1048                 seq_puts(m, prefix);
1049                 if (has_comma)
1050                         seq_putc(m, '\"');
1051                 seq_puts(m, opts->mnt_opts[i]);
1052                 if (has_comma)
1053                         seq_putc(m, '\"');
1054         }
1055 }
1056
1057 static int selinux_sb_show_options(struct seq_file *m, struct super_block *sb)
1058 {
1059         struct security_mnt_opts opts;
1060         int rc;
1061
1062         rc = selinux_get_mnt_opts(sb, &opts);
1063         if (rc) {
1064                 /* before policy load we may get EINVAL, don't show anything */
1065                 if (rc == -EINVAL)
1066                         rc = 0;
1067                 return rc;
1068         }
1069
1070         selinux_write_opts(m, &opts);
1071
1072         security_free_mnt_opts(&opts);
1073
1074         return rc;
1075 }
1076
1077 static inline u16 inode_mode_to_security_class(umode_t mode)
1078 {
1079         switch (mode & S_IFMT) {
1080         case S_IFSOCK:
1081                 return SECCLASS_SOCK_FILE;
1082         case S_IFLNK:
1083                 return SECCLASS_LNK_FILE;
1084         case S_IFREG:
1085                 return SECCLASS_FILE;
1086         case S_IFBLK:
1087                 return SECCLASS_BLK_FILE;
1088         case S_IFDIR:
1089                 return SECCLASS_DIR;
1090         case S_IFCHR:
1091                 return SECCLASS_CHR_FILE;
1092         case S_IFIFO:
1093                 return SECCLASS_FIFO_FILE;
1094
1095         }
1096
1097         return SECCLASS_FILE;
1098 }
1099
1100 static inline int default_protocol_stream(int protocol)
1101 {
1102         return (protocol == IPPROTO_IP || protocol == IPPROTO_TCP);
1103 }
1104
1105 static inline int default_protocol_dgram(int protocol)
1106 {
1107         return (protocol == IPPROTO_IP || protocol == IPPROTO_UDP);
1108 }
1109
1110 static inline u16 socket_type_to_security_class(int family, int type, int protocol)
1111 {
1112         switch (family) {
1113         case PF_UNIX:
1114                 switch (type) {
1115                 case SOCK_STREAM:
1116                 case SOCK_SEQPACKET:
1117                         return SECCLASS_UNIX_STREAM_SOCKET;
1118                 case SOCK_DGRAM:
1119                         return SECCLASS_UNIX_DGRAM_SOCKET;
1120                 }
1121                 break;
1122         case PF_INET:
1123         case PF_INET6:
1124                 switch (type) {
1125                 case SOCK_STREAM:
1126                         if (default_protocol_stream(protocol))
1127                                 return SECCLASS_TCP_SOCKET;
1128                         else
1129                                 return SECCLASS_RAWIP_SOCKET;
1130                 case SOCK_DGRAM:
1131                         if (default_protocol_dgram(protocol))
1132                                 return SECCLASS_UDP_SOCKET;
1133                         else
1134                                 return SECCLASS_RAWIP_SOCKET;
1135                 case SOCK_DCCP:
1136                         return SECCLASS_DCCP_SOCKET;
1137                 default:
1138                         return SECCLASS_RAWIP_SOCKET;
1139                 }
1140                 break;
1141         case PF_NETLINK:
1142                 switch (protocol) {
1143                 case NETLINK_ROUTE:
1144                         return SECCLASS_NETLINK_ROUTE_SOCKET;
1145                 case NETLINK_FIREWALL:
1146                         return SECCLASS_NETLINK_FIREWALL_SOCKET;
1147                 case NETLINK_INET_DIAG:
1148                         return SECCLASS_NETLINK_TCPDIAG_SOCKET;
1149                 case NETLINK_NFLOG:
1150                         return SECCLASS_NETLINK_NFLOG_SOCKET;
1151                 case NETLINK_XFRM:
1152                         return SECCLASS_NETLINK_XFRM_SOCKET;
1153                 case NETLINK_SELINUX:
1154                         return SECCLASS_NETLINK_SELINUX_SOCKET;
1155                 case NETLINK_AUDIT:
1156                         return SECCLASS_NETLINK_AUDIT_SOCKET;
1157                 case NETLINK_IP6_FW:
1158                         return SECCLASS_NETLINK_IP6FW_SOCKET;
1159                 case NETLINK_DNRTMSG:
1160                         return SECCLASS_NETLINK_DNRT_SOCKET;
1161                 case NETLINK_KOBJECT_UEVENT:
1162                         return SECCLASS_NETLINK_KOBJECT_UEVENT_SOCKET;
1163                 default:
1164                         return SECCLASS_NETLINK_SOCKET;
1165                 }
1166         case PF_PACKET:
1167                 return SECCLASS_PACKET_SOCKET;
1168         case PF_KEY:
1169                 return SECCLASS_KEY_SOCKET;
1170         case PF_APPLETALK:
1171                 return SECCLASS_APPLETALK_SOCKET;
1172         }
1173
1174         return SECCLASS_SOCKET;
1175 }
1176
1177 #ifdef CONFIG_PROC_FS
1178 static int selinux_proc_get_sid(struct proc_dir_entry *de,
1179                                 u16 tclass,
1180                                 u32 *sid)
1181 {
1182         int buflen, rc;
1183         char *buffer, *path, *end;
1184
1185         buffer = (char *)__get_free_page(GFP_KERNEL);
1186         if (!buffer)
1187                 return -ENOMEM;
1188
1189         buflen = PAGE_SIZE;
1190         end = buffer+buflen;
1191         *--end = '\0';
1192         buflen--;
1193         path = end-1;
1194         *path = '/';
1195         while (de && de != de->parent) {
1196                 buflen -= de->namelen + 1;
1197                 if (buflen < 0)
1198                         break;
1199                 end -= de->namelen;
1200                 memcpy(end, de->name, de->namelen);
1201                 *--end = '/';
1202                 path = end;
1203                 de = de->parent;
1204         }
1205         rc = security_genfs_sid("proc", path, tclass, sid);
1206         free_page((unsigned long)buffer);
1207         return rc;
1208 }
1209 #else
1210 static int selinux_proc_get_sid(struct proc_dir_entry *de,
1211                                 u16 tclass,
1212                                 u32 *sid)
1213 {
1214         return -EINVAL;
1215 }
1216 #endif
1217
1218 /* The inode's security attributes must be initialized before first use. */
1219 static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dentry)
1220 {
1221         struct superblock_security_struct *sbsec = NULL;
1222         struct inode_security_struct *isec = inode->i_security;
1223         u32 sid;
1224         struct dentry *dentry;
1225 #define INITCONTEXTLEN 255
1226         char *context = NULL;
1227         unsigned len = 0;
1228         int rc = 0;
1229
1230         if (isec->initialized)
1231                 goto out;
1232
1233         mutex_lock(&isec->lock);
1234         if (isec->initialized)
1235                 goto out_unlock;
1236
1237         sbsec = inode->i_sb->s_security;
1238         if (!(sbsec->flags & SE_SBINITIALIZED)) {
1239                 /* Defer initialization until selinux_complete_init,
1240                    after the initial policy is loaded and the security
1241                    server is ready to handle calls. */
1242                 spin_lock(&sbsec->isec_lock);
1243                 if (list_empty(&isec->list))
1244                         list_add(&isec->list, &sbsec->isec_head);
1245                 spin_unlock(&sbsec->isec_lock);
1246                 goto out_unlock;
1247         }
1248
1249         switch (sbsec->behavior) {
1250         case SECURITY_FS_USE_XATTR:
1251                 if (!inode->i_op->getxattr) {
1252                         isec->sid = sbsec->def_sid;
1253                         break;
1254                 }
1255
1256                 /* Need a dentry, since the xattr API requires one.
1257                    Life would be simpler if we could just pass the inode. */
1258                 if (opt_dentry) {
1259                         /* Called from d_instantiate or d_splice_alias. */
1260                         dentry = dget(opt_dentry);
1261                 } else {
1262                         /* Called from selinux_complete_init, try to find a dentry. */
1263                         dentry = d_find_alias(inode);
1264                 }
1265                 if (!dentry) {
1266                         printk(KERN_WARNING "SELinux: %s:  no dentry for dev=%s "
1267                                "ino=%ld\n", __func__, inode->i_sb->s_id,
1268                                inode->i_ino);
1269                         goto out_unlock;
1270                 }
1271
1272                 len = INITCONTEXTLEN;
1273                 context = kmalloc(len, GFP_NOFS);
1274                 if (!context) {
1275                         rc = -ENOMEM;
1276                         dput(dentry);
1277                         goto out_unlock;
1278                 }
1279                 rc = inode->i_op->getxattr(dentry, XATTR_NAME_SELINUX,
1280                                            context, len);
1281                 if (rc == -ERANGE) {
1282                         /* Need a larger buffer.  Query for the right size. */
1283                         rc = inode->i_op->getxattr(dentry, XATTR_NAME_SELINUX,
1284                                                    NULL, 0);
1285                         if (rc < 0) {
1286                                 dput(dentry);
1287                                 goto out_unlock;
1288                         }
1289                         kfree(context);
1290                         len = rc;
1291                         context = kmalloc(len, GFP_NOFS);
1292                         if (!context) {
1293                                 rc = -ENOMEM;
1294                                 dput(dentry);
1295                                 goto out_unlock;
1296                         }
1297                         rc = inode->i_op->getxattr(dentry,
1298                                                    XATTR_NAME_SELINUX,
1299                                                    context, len);
1300                 }
1301                 dput(dentry);
1302                 if (rc < 0) {
1303                         if (rc != -ENODATA) {
1304                                 printk(KERN_WARNING "SELinux: %s:  getxattr returned "
1305                                        "%d for dev=%s ino=%ld\n", __func__,
1306                                        -rc, inode->i_sb->s_id, inode->i_ino);
1307                                 kfree(context);
1308                                 goto out_unlock;
1309                         }
1310                         /* Map ENODATA to the default file SID */
1311                         sid = sbsec->def_sid;
1312                         rc = 0;
1313                 } else {
1314                         rc = security_context_to_sid_default(context, rc, &sid,
1315                                                              sbsec->def_sid,
1316                                                              GFP_NOFS);
1317                         if (rc) {
1318                                 printk(KERN_WARNING "SELinux: %s:  context_to_sid(%s) "
1319                                        "returned %d for dev=%s ino=%ld\n",
1320                                        __func__, context, -rc,
1321                                        inode->i_sb->s_id, inode->i_ino);
1322                                 kfree(context);
1323                                 /* Leave with the unlabeled SID */
1324                                 rc = 0;
1325                                 break;
1326                         }
1327                 }
1328                 kfree(context);
1329                 isec->sid = sid;
1330                 break;
1331         case SECURITY_FS_USE_TASK:
1332                 isec->sid = isec->task_sid;
1333                 break;
1334         case SECURITY_FS_USE_TRANS:
1335                 /* Default to the fs SID. */
1336                 isec->sid = sbsec->sid;
1337
1338                 /* Try to obtain a transition SID. */
1339                 isec->sclass = inode_mode_to_security_class(inode->i_mode);
1340                 rc = security_transition_sid(isec->task_sid,
1341                                              sbsec->sid,
1342                                              isec->sclass,
1343                                              &sid);
1344                 if (rc)
1345                         goto out_unlock;
1346                 isec->sid = sid;
1347                 break;
1348         case SECURITY_FS_USE_MNTPOINT:
1349                 isec->sid = sbsec->mntpoint_sid;
1350                 break;
1351         default:
1352                 /* Default to the fs superblock SID. */
1353                 isec->sid = sbsec->sid;
1354
1355                 if ((sbsec->flags & SE_SBPROC) && !S_ISLNK(inode->i_mode)) {
1356                         struct proc_inode *proci = PROC_I(inode);
1357                         if (proci->pde) {
1358                                 isec->sclass = inode_mode_to_security_class(inode->i_mode);
1359                                 rc = selinux_proc_get_sid(proci->pde,
1360                                                           isec->sclass,
1361                                                           &sid);
1362                                 if (rc)
1363                                         goto out_unlock;
1364                                 isec->sid = sid;
1365                         }
1366                 }
1367                 break;
1368         }
1369
1370         isec->initialized = 1;
1371
1372 out_unlock:
1373         mutex_unlock(&isec->lock);
1374 out:
1375         if (isec->sclass == SECCLASS_FILE)
1376                 isec->sclass = inode_mode_to_security_class(inode->i_mode);
1377         return rc;
1378 }
1379
1380 /* Convert a Linux signal to an access vector. */
1381 static inline u32 signal_to_av(int sig)
1382 {
1383         u32 perm = 0;
1384
1385         switch (sig) {
1386         case SIGCHLD:
1387                 /* Commonly granted from child to parent. */
1388                 perm = PROCESS__SIGCHLD;
1389                 break;
1390         case SIGKILL:
1391                 /* Cannot be caught or ignored */
1392                 perm = PROCESS__SIGKILL;
1393                 break;
1394         case SIGSTOP:
1395                 /* Cannot be caught or ignored */
1396                 perm = PROCESS__SIGSTOP;
1397                 break;
1398         default:
1399                 /* All other signals. */
1400                 perm = PROCESS__SIGNAL;
1401                 break;
1402         }
1403
1404         return perm;
1405 }
1406
1407 /*
1408  * Check permission between a pair of credentials
1409  * fork check, ptrace check, etc.
1410  */
1411 static int cred_has_perm(const struct cred *actor,
1412                          const struct cred *target,
1413                          u32 perms)
1414 {
1415         u32 asid = cred_sid(actor), tsid = cred_sid(target);
1416
1417         return avc_has_perm(asid, tsid, SECCLASS_PROCESS, perms, NULL);
1418 }
1419
1420 /*
1421  * Check permission between a pair of tasks, e.g. signal checks,
1422  * fork check, ptrace check, etc.
1423  * tsk1 is the actor and tsk2 is the target
1424  * - this uses the default subjective creds of tsk1
1425  */
1426 static int task_has_perm(const struct task_struct *tsk1,
1427                          const struct task_struct *tsk2,
1428                          u32 perms)
1429 {
1430         const struct task_security_struct *__tsec1, *__tsec2;
1431         u32 sid1, sid2;
1432
1433         rcu_read_lock();
1434         __tsec1 = __task_cred(tsk1)->security;  sid1 = __tsec1->sid;
1435         __tsec2 = __task_cred(tsk2)->security;  sid2 = __tsec2->sid;
1436         rcu_read_unlock();
1437         return avc_has_perm(sid1, sid2, SECCLASS_PROCESS, perms, NULL);
1438 }
1439
1440 /*
1441  * Check permission between current and another task, e.g. signal checks,
1442  * fork check, ptrace check, etc.
1443  * current is the actor and tsk2 is the target
1444  * - this uses current's subjective creds
1445  */
1446 static int current_has_perm(const struct task_struct *tsk,
1447                             u32 perms)
1448 {
1449         u32 sid, tsid;
1450
1451         sid = current_sid();
1452         tsid = task_sid(tsk);
1453         return avc_has_perm(sid, tsid, SECCLASS_PROCESS, perms, NULL);
1454 }
1455
1456 #if CAP_LAST_CAP > 63
1457 #error Fix SELinux to handle capabilities > 63.
1458 #endif
1459
1460 /* Check whether a task is allowed to use a capability. */
1461 static int task_has_capability(struct task_struct *tsk,
1462                                const struct cred *cred,
1463                                int cap, int audit)
1464 {
1465         struct avc_audit_data ad;
1466         struct av_decision avd;
1467         u16 sclass;
1468         u32 sid = cred_sid(cred);
1469         u32 av = CAP_TO_MASK(cap);
1470         int rc;
1471
1472         AVC_AUDIT_DATA_INIT(&ad, CAP);
1473         ad.tsk = tsk;
1474         ad.u.cap = cap;
1475
1476         switch (CAP_TO_INDEX(cap)) {
1477         case 0:
1478                 sclass = SECCLASS_CAPABILITY;
1479                 break;
1480         case 1:
1481                 sclass = SECCLASS_CAPABILITY2;
1482                 break;
1483         default:
1484                 printk(KERN_ERR
1485                        "SELinux:  out of range capability %d\n", cap);
1486                 BUG();
1487         }
1488
1489         rc = avc_has_perm_noaudit(sid, sid, sclass, av, 0, &avd);
1490         if (audit == SECURITY_CAP_AUDIT)
1491                 avc_audit(sid, sid, sclass, av, &avd, rc, &ad);
1492         return rc;
1493 }
1494
1495 /* Check whether a task is allowed to use a system operation. */
1496 static int task_has_system(struct task_struct *tsk,
1497                            u32 perms)
1498 {
1499         u32 sid = task_sid(tsk);
1500
1501         return avc_has_perm(sid, SECINITSID_KERNEL,
1502                             SECCLASS_SYSTEM, perms, NULL);
1503 }
1504
1505 /* Check whether a task has a particular permission to an inode.
1506    The 'adp' parameter is optional and allows other audit
1507    data to be passed (e.g. the dentry). */
1508 static int inode_has_perm(const struct cred *cred,
1509                           struct inode *inode,
1510                           u32 perms,
1511                           struct avc_audit_data *adp)
1512 {
1513         struct inode_security_struct *isec;
1514         struct avc_audit_data ad;
1515         u32 sid;
1516
1517         if (unlikely(IS_PRIVATE(inode)))
1518                 return 0;
1519
1520         sid = cred_sid(cred);
1521         isec = inode->i_security;
1522
1523         if (!adp) {
1524                 adp = &ad;
1525                 AVC_AUDIT_DATA_INIT(&ad, FS);
1526                 ad.u.fs.inode = inode;
1527         }
1528
1529         return avc_has_perm(sid, isec->sid, isec->sclass, perms, adp);
1530 }
1531
1532 /* Same as inode_has_perm, but pass explicit audit data containing
1533    the dentry to help the auditing code to more easily generate the
1534    pathname if needed. */
1535 static inline int dentry_has_perm(const struct cred *cred,
1536                                   struct vfsmount *mnt,
1537                                   struct dentry *dentry,
1538                                   u32 av)
1539 {
1540         struct inode *inode = dentry->d_inode;
1541         struct avc_audit_data ad;
1542
1543         AVC_AUDIT_DATA_INIT(&ad, FS);
1544         ad.u.fs.path.mnt = mnt;
1545         ad.u.fs.path.dentry = dentry;
1546         return inode_has_perm(cred, inode, av, &ad);
1547 }
1548
1549 /* Check whether a task can use an open file descriptor to
1550    access an inode in a given way.  Check access to the
1551    descriptor itself, and then use dentry_has_perm to
1552    check a particular permission to the file.
1553    Access to the descriptor is implicitly granted if it
1554    has the same SID as the process.  If av is zero, then
1555    access to the file is not checked, e.g. for cases
1556    where only the descriptor is affected like seek. */
1557 static int file_has_perm(const struct cred *cred,
1558                          struct file *file,
1559                          u32 av)
1560 {
1561         struct file_security_struct *fsec = file->f_security;
1562         struct inode *inode = file->f_path.dentry->d_inode;
1563         struct avc_audit_data ad;
1564         u32 sid = cred_sid(cred);
1565         int rc;
1566
1567         AVC_AUDIT_DATA_INIT(&ad, FS);
1568         ad.u.fs.path = file->f_path;
1569
1570         if (sid != fsec->sid) {
1571                 rc = avc_has_perm(sid, fsec->sid,
1572                                   SECCLASS_FD,
1573                                   FD__USE,
1574                                   &ad);
1575                 if (rc)
1576                         goto out;
1577         }
1578
1579         /* av is zero if only checking access to the descriptor. */
1580         rc = 0;
1581         if (av)
1582                 rc = inode_has_perm(cred, inode, av, &ad);
1583
1584 out:
1585         return rc;
1586 }
1587
1588 /* Check whether a task can create a file. */
1589 static int may_create(struct inode *dir,
1590                       struct dentry *dentry,
1591                       u16 tclass)
1592 {
1593         const struct cred *cred = current_cred();
1594         const struct task_security_struct *tsec = cred->security;
1595         struct inode_security_struct *dsec;
1596         struct superblock_security_struct *sbsec;
1597         u32 sid, newsid;
1598         struct avc_audit_data ad;
1599         int rc;
1600
1601         dsec = dir->i_security;
1602         sbsec = dir->i_sb->s_security;
1603
1604         sid = tsec->sid;
1605         newsid = tsec->create_sid;
1606
1607         AVC_AUDIT_DATA_INIT(&ad, FS);
1608         ad.u.fs.path.dentry = dentry;
1609
1610         rc = avc_has_perm(sid, dsec->sid, SECCLASS_DIR,
1611                           DIR__ADD_NAME | DIR__SEARCH,
1612                           &ad);
1613         if (rc)
1614                 return rc;
1615
1616         if (!newsid || !(sbsec->flags & SE_SBLABELSUPP)) {
1617                 rc = security_transition_sid(sid, dsec->sid, tclass, &newsid);
1618                 if (rc)
1619                         return rc;
1620         }
1621
1622         rc = avc_has_perm(sid, newsid, tclass, FILE__CREATE, &ad);
1623         if (rc)
1624                 return rc;
1625
1626         return avc_has_perm(newsid, sbsec->sid,
1627                             SECCLASS_FILESYSTEM,
1628                             FILESYSTEM__ASSOCIATE, &ad);
1629 }
1630
1631 /* Check whether a task can create a key. */
1632 static int may_create_key(u32 ksid,
1633                           struct task_struct *ctx)
1634 {
1635         u32 sid = task_sid(ctx);
1636
1637         return avc_has_perm(sid, ksid, SECCLASS_KEY, KEY__CREATE, NULL);
1638 }
1639
1640 #define MAY_LINK        0
1641 #define MAY_UNLINK      1
1642 #define MAY_RMDIR       2
1643
1644 /* Check whether a task can link, unlink, or rmdir a file/directory. */
1645 static int may_link(struct inode *dir,
1646                     struct dentry *dentry,
1647                     int kind)
1648
1649 {
1650         struct inode_security_struct *dsec, *isec;
1651         struct avc_audit_data ad;
1652         u32 sid = current_sid();
1653         u32 av;
1654         int rc;
1655
1656         dsec = dir->i_security;
1657         isec = dentry->d_inode->i_security;
1658
1659         AVC_AUDIT_DATA_INIT(&ad, FS);
1660         ad.u.fs.path.dentry = dentry;
1661
1662         av = DIR__SEARCH;
1663         av |= (kind ? DIR__REMOVE_NAME : DIR__ADD_NAME);
1664         rc = avc_has_perm(sid, dsec->sid, SECCLASS_DIR, av, &ad);
1665         if (rc)
1666                 return rc;
1667
1668         switch (kind) {
1669         case MAY_LINK:
1670                 av = FILE__LINK;
1671                 break;
1672         case MAY_UNLINK:
1673                 av = FILE__UNLINK;
1674                 break;
1675         case MAY_RMDIR:
1676                 av = DIR__RMDIR;
1677                 break;
1678         default:
1679                 printk(KERN_WARNING "SELinux: %s:  unrecognized kind %d\n",
1680                         __func__, kind);
1681                 return 0;
1682         }
1683
1684         rc = avc_has_perm(sid, isec->sid, isec->sclass, av, &ad);
1685         return rc;
1686 }
1687
1688 static inline int may_rename(struct inode *old_dir,
1689                              struct dentry *old_dentry,
1690                              struct inode *new_dir,
1691                              struct dentry *new_dentry)
1692 {
1693         struct inode_security_struct *old_dsec, *new_dsec, *old_isec, *new_isec;
1694         struct avc_audit_data ad;
1695         u32 sid = current_sid();
1696         u32 av;
1697         int old_is_dir, new_is_dir;
1698         int rc;
1699
1700         old_dsec = old_dir->i_security;
1701         old_isec = old_dentry->d_inode->i_security;
1702         old_is_dir = S_ISDIR(old_dentry->d_inode->i_mode);
1703         new_dsec = new_dir->i_security;
1704
1705         AVC_AUDIT_DATA_INIT(&ad, FS);
1706
1707         ad.u.fs.path.dentry = old_dentry;
1708         rc = avc_has_perm(sid, old_dsec->sid, SECCLASS_DIR,
1709                           DIR__REMOVE_NAME | DIR__SEARCH, &ad);
1710         if (rc)
1711                 return rc;
1712         rc = avc_has_perm(sid, old_isec->sid,
1713                           old_isec->sclass, FILE__RENAME, &ad);
1714         if (rc)
1715                 return rc;
1716         if (old_is_dir && new_dir != old_dir) {
1717                 rc = avc_has_perm(sid, old_isec->sid,
1718                                   old_isec->sclass, DIR__REPARENT, &ad);
1719                 if (rc)
1720                         return rc;
1721         }
1722
1723         ad.u.fs.path.dentry = new_dentry;
1724         av = DIR__ADD_NAME | DIR__SEARCH;
1725         if (new_dentry->d_inode)
1726                 av |= DIR__REMOVE_NAME;
1727         rc = avc_has_perm(sid, new_dsec->sid, SECCLASS_DIR, av, &ad);
1728         if (rc)
1729                 return rc;
1730         if (new_dentry->d_inode) {
1731                 new_isec = new_dentry->d_inode->i_security;
1732                 new_is_dir = S_ISDIR(new_dentry->d_inode->i_mode);
1733                 rc = avc_has_perm(sid, new_isec->sid,
1734                                   new_isec->sclass,
1735                                   (new_is_dir ? DIR__RMDIR : FILE__UNLINK), &ad);
1736                 if (rc)
1737                         return rc;
1738         }
1739
1740         return 0;
1741 }
1742
1743 /* Check whether a task can perform a filesystem operation. */
1744 static int superblock_has_perm(const struct cred *cred,
1745                                struct super_block *sb,
1746                                u32 perms,
1747                                struct avc_audit_data *ad)
1748 {
1749         struct superblock_security_struct *sbsec;
1750         u32 sid = cred_sid(cred);
1751
1752         sbsec = sb->s_security;
1753         return avc_has_perm(sid, sbsec->sid, SECCLASS_FILESYSTEM, perms, ad);
1754 }
1755
1756 /* Convert a Linux mode and permission mask to an access vector. */
1757 static inline u32 file_mask_to_av(int mode, int mask)
1758 {
1759         u32 av = 0;
1760
1761         if ((mode & S_IFMT) != S_IFDIR) {
1762                 if (mask & MAY_EXEC)
1763                         av |= FILE__EXECUTE;
1764                 if (mask & MAY_READ)
1765                         av |= FILE__READ;
1766
1767                 if (mask & MAY_APPEND)
1768                         av |= FILE__APPEND;
1769                 else if (mask & MAY_WRITE)
1770                         av |= FILE__WRITE;
1771
1772         } else {
1773                 if (mask & MAY_EXEC)
1774                         av |= DIR__SEARCH;
1775                 if (mask & MAY_WRITE)
1776                         av |= DIR__WRITE;
1777                 if (mask & MAY_READ)
1778                         av |= DIR__READ;
1779         }
1780
1781         return av;
1782 }
1783
1784 /* Convert a Linux file to an access vector. */
1785 static inline u32 file_to_av(struct file *file)
1786 {
1787         u32 av = 0;
1788
1789         if (file->f_mode & FMODE_READ)
1790                 av |= FILE__READ;
1791         if (file->f_mode & FMODE_WRITE) {
1792                 if (file->f_flags & O_APPEND)
1793                         av |= FILE__APPEND;
1794                 else
1795                         av |= FILE__WRITE;
1796         }
1797         if (!av) {
1798                 /*
1799                  * Special file opened with flags 3 for ioctl-only use.
1800                  */
1801                 av = FILE__IOCTL;
1802         }
1803
1804         return av;
1805 }
1806
1807 /*
1808  * Convert a file to an access vector and include the correct open
1809  * open permission.
1810  */
1811 static inline u32 open_file_to_av(struct file *file)
1812 {
1813         u32 av = file_to_av(file);
1814
1815         if (selinux_policycap_openperm) {
1816                 mode_t mode = file->f_path.dentry->d_inode->i_mode;
1817                 /*
1818                  * lnk files and socks do not really have an 'open'
1819                  */
1820                 if (S_ISREG(mode))
1821                         av |= FILE__OPEN;
1822                 else if (S_ISCHR(mode))
1823                         av |= CHR_FILE__OPEN;
1824                 else if (S_ISBLK(mode))
1825                         av |= BLK_FILE__OPEN;
1826                 else if (S_ISFIFO(mode))
1827                         av |= FIFO_FILE__OPEN;
1828                 else if (S_ISDIR(mode))
1829                         av |= DIR__OPEN;
1830                 else
1831                         printk(KERN_ERR "SELinux: WARNING: inside %s with "
1832                                 "unknown mode:%o\n", __func__, mode);
1833         }
1834         return av;
1835 }
1836
1837 /* Hook functions begin here. */
1838
1839 static int selinux_ptrace_may_access(struct task_struct *child,
1840                                      unsigned int mode)
1841 {
1842         int rc;
1843
1844         rc = secondary_ops->ptrace_may_access(child, mode);
1845         if (rc)
1846                 return rc;
1847
1848         if (mode == PTRACE_MODE_READ) {
1849                 u32 sid = current_sid();
1850                 u32 csid = task_sid(child);
1851                 return avc_has_perm(sid, csid, SECCLASS_FILE, FILE__READ, NULL);
1852         }
1853
1854         return current_has_perm(child, PROCESS__PTRACE);
1855 }
1856
1857 static int selinux_ptrace_traceme(struct task_struct *parent)
1858 {
1859         int rc;
1860
1861         rc = secondary_ops->ptrace_traceme(parent);
1862         if (rc)
1863                 return rc;
1864
1865         return task_has_perm(parent, current, PROCESS__PTRACE);
1866 }
1867
1868 static int selinux_capget(struct task_struct *target, kernel_cap_t *effective,
1869                           kernel_cap_t *inheritable, kernel_cap_t *permitted)
1870 {
1871         int error;
1872
1873         error = current_has_perm(target, PROCESS__GETCAP);
1874         if (error)
1875                 return error;
1876
1877         return secondary_ops->capget(target, effective, inheritable, permitted);
1878 }
1879
1880 static int selinux_capset(struct cred *new, const struct cred *old,
1881                           const kernel_cap_t *effective,
1882                           const kernel_cap_t *inheritable,
1883                           const kernel_cap_t *permitted)
1884 {
1885         int error;
1886
1887         error = secondary_ops->capset(new, old,
1888                                       effective, inheritable, permitted);
1889         if (error)
1890                 return error;
1891
1892         return cred_has_perm(old, new, PROCESS__SETCAP);
1893 }
1894
1895 static int selinux_capable(struct task_struct *tsk, const struct cred *cred,
1896                            int cap, int audit)
1897 {
1898         int rc;
1899
1900         rc = secondary_ops->capable(tsk, cred, cap, audit);
1901         if (rc)
1902                 return rc;
1903
1904         return task_has_capability(tsk, cred, cap, audit);
1905 }
1906
1907 static int selinux_sysctl_get_sid(ctl_table *table, u16 tclass, u32 *sid)
1908 {
1909         int buflen, rc;
1910         char *buffer, *path, *end;
1911
1912         rc = -ENOMEM;
1913         buffer = (char *)__get_free_page(GFP_KERNEL);
1914         if (!buffer)
1915                 goto out;
1916
1917         buflen = PAGE_SIZE;
1918         end = buffer+buflen;
1919         *--end = '\0';
1920         buflen--;
1921         path = end-1;
1922         *path = '/';
1923         while (table) {
1924                 const char *name = table->procname;
1925                 size_t namelen = strlen(name);
1926                 buflen -= namelen + 1;
1927                 if (buflen < 0)
1928                         goto out_free;
1929                 end -= namelen;
1930                 memcpy(end, name, namelen);
1931                 *--end = '/';
1932                 path = end;
1933                 table = table->parent;
1934         }
1935         buflen -= 4;
1936         if (buflen < 0)
1937                 goto out_free;
1938         end -= 4;
1939         memcpy(end, "/sys", 4);
1940         path = end;
1941         rc = security_genfs_sid("proc", path, tclass, sid);
1942 out_free:
1943         free_page((unsigned long)buffer);
1944 out:
1945         return rc;
1946 }
1947
1948 static int selinux_sysctl(ctl_table *table, int op)
1949 {
1950         int error = 0;
1951         u32 av;
1952         u32 tsid, sid;
1953         int rc;
1954
1955         rc = secondary_ops->sysctl(table, op);
1956         if (rc)
1957                 return rc;
1958
1959         sid = current_sid();
1960
1961         rc = selinux_sysctl_get_sid(table, (op == 0001) ?
1962                                     SECCLASS_DIR : SECCLASS_FILE, &tsid);
1963         if (rc) {
1964                 /* Default to the well-defined sysctl SID. */
1965                 tsid = SECINITSID_SYSCTL;
1966         }
1967
1968         /* The op values are "defined" in sysctl.c, thereby creating
1969          * a bad coupling between this module and sysctl.c */
1970         if (op == 001) {
1971                 error = avc_has_perm(sid, tsid,
1972                                      SECCLASS_DIR, DIR__SEARCH, NULL);
1973         } else {
1974                 av = 0;
1975                 if (op & 004)
1976                         av |= FILE__READ;
1977                 if (op & 002)
1978                         av |= FILE__WRITE;
1979                 if (av)
1980                         error = avc_has_perm(sid, tsid,
1981                                              SECCLASS_FILE, av, NULL);
1982         }
1983
1984         return error;
1985 }
1986
1987 static int selinux_quotactl(int cmds, int type, int id, struct super_block *sb)
1988 {
1989         const struct cred *cred = current_cred();
1990         int rc = 0;
1991
1992         if (!sb)
1993                 return 0;
1994
1995         switch (cmds) {
1996         case Q_SYNC:
1997         case Q_QUOTAON:
1998         case Q_QUOTAOFF:
1999         case Q_SETINFO:
2000         case Q_SETQUOTA:
2001                 rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAMOD, NULL);
2002                 break;
2003         case Q_GETFMT:
2004         case Q_GETINFO:
2005         case Q_GETQUOTA:
2006                 rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAGET, NULL);
2007                 break;
2008         default:
2009                 rc = 0;  /* let the kernel handle invalid cmds */
2010                 break;
2011         }
2012         return rc;
2013 }
2014
2015 static int selinux_quota_on(struct dentry *dentry)
2016 {
2017         const struct cred *cred = current_cred();
2018
2019         return dentry_has_perm(cred, NULL, dentry, FILE__QUOTAON);
2020 }
2021
2022 static int selinux_syslog(int type)
2023 {
2024         int rc;
2025
2026         rc = secondary_ops->syslog(type);
2027         if (rc)
2028                 return rc;
2029
2030         switch (type) {
2031         case 3:         /* Read last kernel messages */
2032         case 10:        /* Return size of the log buffer */
2033                 rc = task_has_system(current, SYSTEM__SYSLOG_READ);
2034                 break;
2035         case 6:         /* Disable logging to console */
2036         case 7:         /* Enable logging to console */
2037         case 8:         /* Set level of messages printed to console */
2038                 rc = task_has_system(current, SYSTEM__SYSLOG_CONSOLE);
2039                 break;
2040         case 0:         /* Close log */
2041         case 1:         /* Open log */
2042         case 2:         /* Read from log */
2043         case 4:         /* Read/clear last kernel messages */
2044         case 5:         /* Clear ring buffer */
2045         default:
2046                 rc = task_has_system(current, SYSTEM__SYSLOG_MOD);
2047                 break;
2048         }
2049         return rc;
2050 }
2051
2052 /*
2053  * Check that a process has enough memory to allocate a new virtual
2054  * mapping. 0 means there is enough memory for the allocation to
2055  * succeed and -ENOMEM implies there is not.
2056  *
2057  * Note that secondary_ops->capable and task_has_perm_noaudit return 0
2058  * if the capability is granted, but __vm_enough_memory requires 1 if
2059  * the capability is granted.
2060  *
2061  * Do not audit the selinux permission check, as this is applied to all
2062  * processes that allocate mappings.
2063  */
2064 static int selinux_vm_enough_memory(struct mm_struct *mm, long pages)
2065 {
2066         int rc, cap_sys_admin = 0;
2067
2068         rc = selinux_capable(current, current_cred(), CAP_SYS_ADMIN,
2069                              SECURITY_CAP_NOAUDIT);
2070         if (rc == 0)
2071                 cap_sys_admin = 1;
2072
2073         return __vm_enough_memory(mm, pages, cap_sys_admin);
2074 }
2075
2076 /* binprm security operations */
2077
2078 static int selinux_bprm_set_creds(struct linux_binprm *bprm)
2079 {
2080         const struct task_security_struct *old_tsec;
2081         struct task_security_struct *new_tsec;
2082         struct inode_security_struct *isec;
2083         struct avc_audit_data ad;
2084         struct inode *inode = bprm->file->f_path.dentry->d_inode;
2085         int rc;
2086
2087         rc = secondary_ops->bprm_set_creds(bprm);
2088         if (rc)
2089                 return rc;
2090
2091         /* SELinux context only depends on initial program or script and not
2092          * the script interpreter */
2093         if (bprm->cred_prepared)
2094                 return 0;
2095
2096         old_tsec = current_security();
2097         new_tsec = bprm->cred->security;
2098         isec = inode->i_security;
2099
2100         /* Default to the current task SID. */
2101         new_tsec->sid = old_tsec->sid;
2102         new_tsec->osid = old_tsec->sid;
2103
2104         /* Reset fs, key, and sock SIDs on execve. */
2105         new_tsec->create_sid = 0;
2106         new_tsec->keycreate_sid = 0;
2107         new_tsec->sockcreate_sid = 0;
2108
2109         if (old_tsec->exec_sid) {
2110                 new_tsec->sid = old_tsec->exec_sid;
2111                 /* Reset exec SID on execve. */
2112                 new_tsec->exec_sid = 0;
2113         } else {
2114                 /* Check for a default transition on this program. */
2115                 rc = security_transition_sid(old_tsec->sid, isec->sid,
2116                                              SECCLASS_PROCESS, &new_tsec->sid);
2117                 if (rc)
2118                         return rc;
2119         }
2120
2121         AVC_AUDIT_DATA_INIT(&ad, FS);
2122         ad.u.fs.path = bprm->file->f_path;
2123
2124         if (bprm->file->f_path.mnt->mnt_flags & MNT_NOSUID)
2125                 new_tsec->sid = old_tsec->sid;
2126
2127         if (new_tsec->sid == old_tsec->sid) {
2128                 rc = avc_has_perm(old_tsec->sid, isec->sid,
2129                                   SECCLASS_FILE, FILE__EXECUTE_NO_TRANS, &ad);
2130                 if (rc)
2131                         return rc;
2132         } else {
2133                 /* Check permissions for the transition. */
2134                 rc = avc_has_perm(old_tsec->sid, new_tsec->sid,
2135                                   SECCLASS_PROCESS, PROCESS__TRANSITION, &ad);
2136                 if (rc)
2137                         return rc;
2138
2139                 rc = avc_has_perm(new_tsec->sid, isec->sid,
2140                                   SECCLASS_FILE, FILE__ENTRYPOINT, &ad);
2141                 if (rc)
2142                         return rc;
2143
2144                 /* Check for shared state */
2145                 if (bprm->unsafe & LSM_UNSAFE_SHARE) {
2146                         rc = avc_has_perm(old_tsec->sid, new_tsec->sid,
2147                                           SECCLASS_PROCESS, PROCESS__SHARE,
2148                                           NULL);
2149                         if (rc)
2150                                 return -EPERM;
2151                 }
2152
2153                 /* Make sure that anyone attempting to ptrace over a task that
2154                  * changes its SID has the appropriate permit */
2155                 if (bprm->unsafe &
2156                     (LSM_UNSAFE_PTRACE | LSM_UNSAFE_PTRACE_CAP)) {
2157                         struct task_struct *tracer;
2158                         struct task_security_struct *sec;
2159                         u32 ptsid = 0;
2160
2161                         rcu_read_lock();
2162                         tracer = tracehook_tracer_task(current);
2163                         if (likely(tracer != NULL)) {
2164                                 sec = __task_cred(tracer)->security;
2165                                 ptsid = sec->sid;
2166                         }
2167                         rcu_read_unlock();
2168
2169                         if (ptsid != 0) {
2170                                 rc = avc_has_perm(ptsid, new_tsec->sid,
2171                                                   SECCLASS_PROCESS,
2172                                                   PROCESS__PTRACE, NULL);
2173                                 if (rc)
2174                                         return -EPERM;
2175                         }
2176                 }
2177
2178                 /* Clear any possibly unsafe personality bits on exec: */
2179                 bprm->per_clear |= PER_CLEAR_ON_SETID;
2180         }
2181
2182         return 0;
2183 }
2184
2185 static int selinux_bprm_secureexec(struct linux_binprm *bprm)
2186 {
2187         const struct cred *cred = current_cred();
2188         const struct task_security_struct *tsec = cred->security;
2189         u32 sid, osid;
2190         int atsecure = 0;
2191
2192         sid = tsec->sid;
2193         osid = tsec->osid;
2194
2195         if (osid != sid) {
2196                 /* Enable secure mode for SIDs transitions unless
2197                    the noatsecure permission is granted between
2198                    the two SIDs, i.e. ahp returns 0. */
2199                 atsecure = avc_has_perm(osid, sid,
2200                                         SECCLASS_PROCESS,
2201                                         PROCESS__NOATSECURE, NULL);
2202         }
2203
2204         return (atsecure || secondary_ops->bprm_secureexec(bprm));
2205 }
2206
2207 extern struct vfsmount *selinuxfs_mount;
2208 extern struct dentry *selinux_null;
2209
2210 /* Derived from fs/exec.c:flush_old_files. */
2211 static inline void flush_unauthorized_files(const struct cred *cred,
2212                                             struct files_struct *files)
2213 {
2214         struct avc_audit_data ad;
2215         struct file *file, *devnull = NULL;
2216         struct tty_struct *tty;
2217         struct fdtable *fdt;
2218         long j = -1;
2219         int drop_tty = 0;
2220
2221         tty = get_current_tty();
2222         if (tty) {
2223                 file_list_lock();
2224                 if (!list_empty(&tty->tty_files)) {
2225                         struct inode *inode;
2226
2227                         /* Revalidate access to controlling tty.
2228                            Use inode_has_perm on the tty inode directly rather
2229                            than using file_has_perm, as this particular open
2230                            file may belong to another process and we are only
2231                            interested in the inode-based check here. */
2232                         file = list_first_entry(&tty->tty_files, struct file, f_u.fu_list);
2233                         inode = file->f_path.dentry->d_inode;
2234                         if (inode_has_perm(cred, inode,
2235                                            FILE__READ | FILE__WRITE, NULL)) {
2236                                 drop_tty = 1;
2237                         }
2238                 }
2239                 file_list_unlock();
2240                 tty_kref_put(tty);
2241         }
2242         /* Reset controlling tty. */
2243         if (drop_tty)
2244                 no_tty();
2245
2246         /* Revalidate access to inherited open files. */
2247
2248         AVC_AUDIT_DATA_INIT(&ad, FS);
2249
2250         spin_lock(&files->file_lock);
2251         for (;;) {
2252                 unsigned long set, i;
2253                 int fd;
2254
2255                 j++;
2256                 i = j * __NFDBITS;
2257                 fdt = files_fdtable(files);
2258                 if (i >= fdt->max_fds)
2259                         break;
2260                 set = fdt->open_fds->fds_bits[j];
2261                 if (!set)
2262                         continue;
2263                 spin_unlock(&files->file_lock);
2264                 for ( ; set ; i++, set >>= 1) {
2265                         if (set & 1) {
2266                                 file = fget(i);
2267                                 if (!file)
2268                                         continue;
2269                                 if (file_has_perm(cred,
2270                                                   file,
2271                                                   file_to_av(file))) {
2272                                         sys_close(i);
2273                                         fd = get_unused_fd();
2274                                         if (fd != i) {
2275                                                 if (fd >= 0)
2276                                                         put_unused_fd(fd);
2277                                                 fput(file);
2278                                                 continue;
2279                                         }
2280                                         if (devnull) {
2281                                                 get_file(devnull);
2282                                         } else {
2283                                                 devnull = dentry_open(
2284                                                         dget(selinux_null),
2285                                                         mntget(selinuxfs_mount),
2286                                                         O_RDWR, cred);
2287                                                 if (IS_ERR(devnull)) {
2288                                                         devnull = NULL;
2289                                                         put_unused_fd(fd);
2290                                                         fput(file);
2291                                                         continue;
2292                                                 }
2293                                         }
2294                                         fd_install(fd, devnull);
2295                                 }
2296                                 fput(file);
2297                         }
2298                 }
2299                 spin_lock(&files->file_lock);
2300
2301         }
2302         spin_unlock(&files->file_lock);
2303 }
2304
2305 /*
2306  * Prepare a process for imminent new credential changes due to exec
2307  */
2308 static void selinux_bprm_committing_creds(struct linux_binprm *bprm)
2309 {
2310         struct task_security_struct *new_tsec;
2311         struct rlimit *rlim, *initrlim;
2312         int rc, i;
2313
2314         new_tsec = bprm->cred->security;
2315         if (new_tsec->sid == new_tsec->osid)
2316                 return;
2317
2318         /* Close files for which the new task SID is not authorized. */
2319         flush_unauthorized_files(bprm->cred, current->files);
2320
2321         /* Always clear parent death signal on SID transitions. */
2322         current->pdeath_signal = 0;
2323
2324         /* Check whether the new SID can inherit resource limits from the old
2325          * SID.  If not, reset all soft limits to the lower of the current
2326          * task's hard limit and the init task's soft limit.
2327          *
2328          * Note that the setting of hard limits (even to lower them) can be
2329          * controlled by the setrlimit check.  The inclusion of the init task's
2330          * soft limit into the computation is to avoid resetting soft limits
2331          * higher than the default soft limit for cases where the default is
2332          * lower than the hard limit, e.g. RLIMIT_CORE or RLIMIT_STACK.
2333          */
2334         rc = avc_has_perm(new_tsec->osid, new_tsec->sid, SECCLASS_PROCESS,
2335                           PROCESS__RLIMITINH, NULL);
2336         if (rc) {
2337                 for (i = 0; i < RLIM_NLIMITS; i++) {
2338                         rlim = current->signal->rlim + i;
2339                         initrlim = init_task.signal->rlim + i;
2340                         rlim->rlim_cur = min(rlim->rlim_max, initrlim->rlim_cur);
2341                 }
2342                 update_rlimit_cpu(rlim->rlim_cur);
2343         }
2344 }
2345
2346 /*
2347  * Clean up the process immediately after the installation of new credentials
2348  * due to exec
2349  */
2350 static void selinux_bprm_committed_creds(struct linux_binprm *bprm)
2351 {
2352         const struct task_security_struct *tsec = current_security();
2353         struct itimerval itimer;
2354         struct sighand_struct *psig;
2355         u32 osid, sid;
2356         int rc, i;
2357         unsigned long flags;
2358
2359         osid = tsec->osid;
2360         sid = tsec->sid;
2361
2362         if (sid == osid)
2363                 return;
2364
2365         /* Check whether the new SID can inherit signal state from the old SID.
2366          * If not, clear itimers to avoid subsequent signal generation and
2367          * flush and unblock signals.
2368          *
2369          * This must occur _after_ the task SID has been updated so that any
2370          * kill done after the flush will be checked against the new SID.
2371          */
2372         rc = avc_has_perm(osid, sid, SECCLASS_PROCESS, PROCESS__SIGINH, NULL);
2373         if (rc) {
2374                 memset(&itimer, 0, sizeof itimer);
2375                 for (i = 0; i < 3; i++)
2376                         do_setitimer(i, &itimer, NULL);
2377                 flush_signals(current);
2378                 spin_lock_irq(&current->sighand->siglock);
2379                 flush_signal_handlers(current, 1);
2380                 sigemptyset(&current->blocked);
2381                 recalc_sigpending();
2382                 spin_unlock_irq(&current->sighand->siglock);
2383         }
2384
2385         /* Wake up the parent if it is waiting so that it can recheck
2386          * wait permission to the new task SID. */
2387         read_lock_irq(&tasklist_lock);
2388         psig = current->parent->sighand;
2389         spin_lock_irqsave(&psig->siglock, flags);
2390         wake_up_interruptible(&current->parent->signal->wait_chldexit);
2391         spin_unlock_irqrestore(&psig->siglock, flags);
2392         read_unlock_irq(&tasklist_lock);
2393 }
2394
2395 /* superblock security operations */
2396
2397 static int selinux_sb_alloc_security(struct super_block *sb)
2398 {
2399         return superblock_alloc_security(sb);
2400 }
2401
2402 static void selinux_sb_free_security(struct super_block *sb)
2403 {
2404         superblock_free_security(sb);
2405 }
2406
2407 static inline int match_prefix(char *prefix, int plen, char *option, int olen)
2408 {
2409         if (plen > olen)
2410                 return 0;
2411
2412         return !memcmp(prefix, option, plen);
2413 }
2414
2415 static inline int selinux_option(char *option, int len)
2416 {
2417         return (match_prefix(CONTEXT_STR, sizeof(CONTEXT_STR)-1, option, len) ||
2418                 match_prefix(FSCONTEXT_STR, sizeof(FSCONTEXT_STR)-1, option, len) ||
2419                 match_prefix(DEFCONTEXT_STR, sizeof(DEFCONTEXT_STR)-1, option, len) ||
2420                 match_prefix(ROOTCONTEXT_STR, sizeof(ROOTCONTEXT_STR)-1, option, len) ||
2421                 match_prefix(LABELSUPP_STR, sizeof(LABELSUPP_STR)-1, option, len));
2422 }
2423
2424 static inline void take_option(char **to, char *from, int *first, int len)
2425 {
2426         if (!*first) {
2427                 **to = ',';
2428                 *to += 1;
2429         } else
2430                 *first = 0;
2431         memcpy(*to, from, len);
2432         *to += len;
2433 }
2434
2435 static inline void take_selinux_option(char **to, char *from, int *first,
2436                                        int len)
2437 {
2438         int current_size = 0;
2439
2440         if (!*first) {
2441                 **to = '|';
2442                 *to += 1;
2443         } else
2444                 *first = 0;
2445
2446         while (current_size < len) {
2447                 if (*from != '"') {
2448                         **to = *from;
2449                         *to += 1;
2450                 }
2451                 from += 1;
2452                 current_size += 1;
2453         }
2454 }
2455
2456 static int selinux_sb_copy_data(char *orig, char *copy)
2457 {
2458         int fnosec, fsec, rc = 0;
2459         char *in_save, *in_curr, *in_end;
2460         char *sec_curr, *nosec_save, *nosec;
2461         int open_quote = 0;
2462
2463         in_curr = orig;
2464         sec_curr = copy;
2465
2466         nosec = (char *)get_zeroed_page(GFP_KERNEL);
2467         if (!nosec) {
2468                 rc = -ENOMEM;
2469                 goto out;
2470         }
2471
2472         nosec_save = nosec;
2473         fnosec = fsec = 1;
2474         in_save = in_end = orig;
2475
2476         do {
2477                 if (*in_end == '"')
2478                         open_quote = !open_quote;
2479                 if ((*in_end == ',' && open_quote == 0) ||
2480                                 *in_end == '\0') {
2481                         int len = in_end - in_curr;
2482
2483                         if (selinux_option(in_curr, len))
2484                                 take_selinux_option(&sec_curr, in_curr, &fsec, len);
2485                         else
2486                                 take_option(&nosec, in_curr, &fnosec, len);
2487
2488                         in_curr = in_end + 1;
2489                 }
2490         } while (*in_end++);
2491
2492         strcpy(in_save, nosec_save);
2493         free_page((unsigned long)nosec_save);
2494 out:
2495         return rc;
2496 }
2497
2498 static int selinux_sb_kern_mount(struct super_block *sb, int flags, void *data)
2499 {
2500         const struct cred *cred = current_cred();
2501         struct avc_audit_data ad;
2502         int rc;
2503
2504         rc = superblock_doinit(sb, data);
2505         if (rc)
2506                 return rc;
2507
2508         /* Allow all mounts performed by the kernel */
2509         if (flags & MS_KERNMOUNT)
2510                 return 0;
2511
2512         AVC_AUDIT_DATA_INIT(&ad, FS);
2513         ad.u.fs.path.dentry = sb->s_root;
2514         return superblock_has_perm(cred, sb, FILESYSTEM__MOUNT, &ad);
2515 }
2516
2517 static int selinux_sb_statfs(struct dentry *dentry)
2518 {
2519         const struct cred *cred = current_cred();
2520         struct avc_audit_data ad;
2521
2522         AVC_AUDIT_DATA_INIT(&ad, FS);
2523         ad.u.fs.path.dentry = dentry->d_sb->s_root;
2524         return superblock_has_perm(cred, dentry->d_sb, FILESYSTEM__GETATTR, &ad);
2525 }
2526
2527 static int selinux_mount(char *dev_name,
2528                          struct path *path,
2529                          char *type,
2530                          unsigned long flags,
2531                          void *data)
2532 {
2533         const struct cred *cred = current_cred();
2534
2535         if (flags & MS_REMOUNT)
2536                 return superblock_has_perm(cred, path->mnt->mnt_sb,
2537                                            FILESYSTEM__REMOUNT, NULL);
2538         else
2539                 return dentry_has_perm(cred, path->mnt, path->dentry,
2540                                        FILE__MOUNTON);
2541 }
2542
2543 static int selinux_umount(struct vfsmount *mnt, int flags)
2544 {
2545         const struct cred *cred = current_cred();
2546
2547         return superblock_has_perm(cred, mnt->mnt_sb,
2548                                    FILESYSTEM__UNMOUNT, NULL);
2549 }
2550
2551 /* inode security operations */
2552
2553 static int selinux_inode_alloc_security(struct inode *inode)
2554 {
2555         return inode_alloc_security(inode);
2556 }
2557
2558 static void selinux_inode_free_security(struct inode *inode)
2559 {
2560         inode_free_security(inode);
2561 }
2562
2563 static int selinux_inode_init_security(struct inode *inode, struct inode *dir,
2564                                        char **name, void **value,
2565                                        size_t *len)
2566 {
2567         const struct cred *cred = current_cred();
2568         const struct task_security_struct *tsec = cred->security;
2569         struct inode_security_struct *dsec;
2570         struct superblock_security_struct *sbsec;
2571         u32 sid, newsid, clen;
2572         int rc;
2573         char *namep = NULL, *context;
2574
2575         dsec = dir->i_security;
2576         sbsec = dir->i_sb->s_security;
2577
2578         sid = tsec->sid;
2579         newsid = tsec->create_sid;
2580
2581         if (!newsid || !(sbsec->flags & SE_SBLABELSUPP)) {
2582                 rc = security_transition_sid(sid, dsec->sid,
2583                                              inode_mode_to_security_class(inode->i_mode),
2584                                              &newsid);
2585                 if (rc) {
2586                         printk(KERN_WARNING "%s:  "
2587                                "security_transition_sid failed, rc=%d (dev=%s "
2588                                "ino=%ld)\n",
2589                                __func__,
2590                                -rc, inode->i_sb->s_id, inode->i_ino);
2591                         return rc;
2592                 }
2593         }
2594
2595         /* Possibly defer initialization to selinux_complete_init. */
2596         if (sbsec->flags & SE_SBINITIALIZED) {
2597                 struct inode_security_struct *isec = inode->i_security;
2598                 isec->sclass = inode_mode_to_security_class(inode->i_mode);
2599                 isec->sid = newsid;
2600                 isec->initialized = 1;
2601         }
2602
2603         if (!ss_initialized || !(sbsec->flags & SE_SBLABELSUPP))
2604                 return -EOPNOTSUPP;
2605
2606         if (name) {
2607                 namep = kstrdup(XATTR_SELINUX_SUFFIX, GFP_NOFS);
2608                 if (!namep)
2609                         return -ENOMEM;
2610                 *name = namep;
2611         }
2612
2613         if (value && len) {
2614                 rc = security_sid_to_context_force(newsid, &context, &clen);
2615                 if (rc) {
2616                         kfree(namep);
2617                         return rc;
2618                 }
2619                 *value = context;
2620                 *len = clen;
2621         }
2622
2623         return 0;
2624 }
2625
2626 static int selinux_inode_create(struct inode *dir, struct dentry *dentry, int mask)
2627 {
2628         return may_create(dir, dentry, SECCLASS_FILE);
2629 }
2630
2631 static int selinux_inode_link(struct dentry *old_dentry, struct inode *dir, struct dentry *new_dentry)
2632 {
2633         return may_link(dir, old_dentry, MAY_LINK);
2634 }
2635
2636 static int selinux_inode_unlink(struct inode *dir, struct dentry *dentry)
2637 {
2638         return may_link(dir, dentry, MAY_UNLINK);
2639 }
2640
2641 static int selinux_inode_symlink(struct inode *dir, struct dentry *dentry, const char *name)
2642 {
2643         return may_create(dir, dentry, SECCLASS_LNK_FILE);
2644 }
2645
2646 static int selinux_inode_mkdir(struct inode *dir, struct dentry *dentry, int mask)
2647 {
2648         return may_create(dir, dentry, SECCLASS_DIR);
2649 }
2650
2651 static int selinux_inode_rmdir(struct inode *dir, struct dentry *dentry)
2652 {
2653         return may_link(dir, dentry, MAY_RMDIR);
2654 }
2655
2656 static int selinux_inode_mknod(struct inode *dir, struct dentry *dentry, int mode, dev_t dev)
2657 {
2658         return may_create(dir, dentry, inode_mode_to_security_class(mode));
2659 }
2660
2661 static int selinux_inode_rename(struct inode *old_inode, struct dentry *old_dentry,
2662                                 struct inode *new_inode, struct dentry *new_dentry)
2663 {
2664         return may_rename(old_inode, old_dentry, new_inode, new_dentry);
2665 }
2666
2667 static int selinux_inode_readlink(struct dentry *dentry)
2668 {
2669         const struct cred *cred = current_cred();
2670
2671         return dentry_has_perm(cred, NULL, dentry, FILE__READ);
2672 }
2673
2674 static int selinux_inode_follow_link(struct dentry *dentry, struct nameidata *nameidata)
2675 {
2676         const struct cred *cred = current_cred();
2677
2678         return dentry_has_perm(cred, NULL, dentry, FILE__READ);
2679 }
2680
2681 static int selinux_inode_permission(struct inode *inode, int mask)
2682 {
2683         const struct cred *cred = current_cred();
2684
2685         if (!mask) {
2686                 /* No permission to check.  Existence test. */
2687                 return 0;
2688         }
2689
2690         return inode_has_perm(cred, inode,
2691                               file_mask_to_av(inode->i_mode, mask), NULL);
2692 }
2693
2694 static int selinux_inode_setattr(struct dentry *dentry, struct iattr *iattr)
2695 {
2696         const struct cred *cred = current_cred();
2697
2698         if (iattr->ia_valid & ATTR_FORCE)
2699                 return 0;
2700
2701         if (iattr->ia_valid & (ATTR_MODE | ATTR_UID | ATTR_GID |
2702                                ATTR_ATIME_SET | ATTR_MTIME_SET))
2703                 return dentry_has_perm(cred, NULL, dentry, FILE__SETATTR);
2704
2705         return dentry_has_perm(cred, NULL, dentry, FILE__WRITE);
2706 }
2707
2708 static int selinux_inode_getattr(struct vfsmount *mnt, struct dentry *dentry)
2709 {
2710         const struct cred *cred = current_cred();
2711
2712         return dentry_has_perm(cred, mnt, dentry, FILE__GETATTR);
2713 }
2714
2715 static int selinux_inode_setotherxattr(struct dentry *dentry, const char *name)
2716 {
2717         const struct cred *cred = current_cred();
2718
2719         if (!strncmp(name, XATTR_SECURITY_PREFIX,
2720                      sizeof XATTR_SECURITY_PREFIX - 1)) {
2721                 if (!strcmp(name, XATTR_NAME_CAPS)) {
2722                         if (!capable(CAP_SETFCAP))
2723                                 return -EPERM;
2724                 } else if (!capable(CAP_SYS_ADMIN)) {
2725                         /* A different attribute in the security namespace.
2726                            Restrict to administrator. */
2727                         return -EPERM;
2728                 }
2729         }
2730
2731         /* Not an attribute we recognize, so just check the
2732            ordinary setattr permission. */
2733         return dentry_has_perm(cred, NULL, dentry, FILE__SETATTR);
2734 }
2735
2736 static int selinux_inode_setxattr(struct dentry *dentry, const char *name,
2737                                   const void *value, size_t size, int flags)
2738 {
2739         struct inode *inode = dentry->d_inode;
2740         struct inode_security_struct *isec = inode->i_security;
2741         struct superblock_security_struct *sbsec;
2742         struct avc_audit_data ad;
2743         u32 newsid, sid = current_sid();
2744         int rc = 0;
2745
2746         if (strcmp(name, XATTR_NAME_SELINUX))
2747                 return selinux_inode_setotherxattr(dentry, name);
2748
2749         sbsec = inode->i_sb->s_security;
2750         if (!(sbsec->flags & SE_SBLABELSUPP))
2751                 return -EOPNOTSUPP;
2752
2753         if (!is_owner_or_cap(inode))
2754                 return -EPERM;
2755
2756         AVC_AUDIT_DATA_INIT(&ad, FS);
2757         ad.u.fs.path.dentry = dentry;
2758
2759         rc = avc_has_perm(sid, isec->sid, isec->sclass,
2760                           FILE__RELABELFROM, &ad);
2761         if (rc)
2762                 return rc;
2763
2764         rc = security_context_to_sid(value, size, &newsid);
2765         if (rc == -EINVAL) {
2766                 if (!capable(CAP_MAC_ADMIN))
2767                         return rc;
2768                 rc = security_context_to_sid_force(value, size, &newsid);
2769         }
2770         if (rc)
2771                 return rc;
2772
2773         rc = avc_has_perm(sid, newsid, isec->sclass,
2774                           FILE__RELABELTO, &ad);
2775         if (rc)
2776                 return rc;
2777
2778         rc = security_validate_transition(isec->sid, newsid, sid,
2779                                           isec->sclass);
2780         if (rc)
2781                 return rc;
2782
2783         return avc_has_perm(newsid,
2784                             sbsec->sid,
2785                             SECCLASS_FILESYSTEM,
2786                             FILESYSTEM__ASSOCIATE,
2787                             &ad);
2788 }
2789
2790 static void selinux_inode_post_setxattr(struct dentry *dentry, const char *name,
2791                                         const void *value, size_t size,
2792                                         int flags)
2793 {
2794         struct inode *inode = dentry->d_inode;
2795         struct inode_security_struct *isec = inode->i_security;
2796         u32 newsid;
2797         int rc;
2798
2799         if (strcmp(name, XATTR_NAME_SELINUX)) {
2800                 /* Not an attribute we recognize, so nothing to do. */
2801                 return;
2802         }
2803
2804         rc = security_context_to_sid_force(value, size, &newsid);
2805         if (rc) {
2806                 printk(KERN_ERR "SELinux:  unable to map context to SID"
2807                        "for (%s, %lu), rc=%d\n",
2808                        inode->i_sb->s_id, inode->i_ino, -rc);
2809                 return;
2810         }
2811
2812         isec->sid = newsid;
2813         return;
2814 }
2815
2816 static int selinux_inode_getxattr(struct dentry *dentry, const char *name)
2817 {
2818         const struct cred *cred = current_cred();
2819
2820         return dentry_has_perm(cred, NULL, dentry, FILE__GETATTR);
2821 }
2822
2823 static int selinux_inode_listxattr(struct dentry *dentry)
2824 {
2825         const struct cred *cred = current_cred();
2826
2827         return dentry_has_perm(cred, NULL, dentry, FILE__GETATTR);
2828 }
2829
2830 static int selinux_inode_removexattr(struct dentry *dentry, const char *name)
2831 {
2832         if (strcmp(name, XATTR_NAME_SELINUX))
2833                 return selinux_inode_setotherxattr(dentry, name);
2834
2835         /* No one is allowed to remove a SELinux security label.
2836            You can change the label, but all data must be labeled. */
2837         return -EACCES;
2838 }
2839
2840 /*
2841  * Copy the inode security context value to the user.
2842  *
2843  * Permission check is handled by selinux_inode_getxattr hook.
2844  */
2845 static int selinux_inode_getsecurity(const struct inode *inode, const char *name, void **buffer, bool alloc)
2846 {
2847         u32 size;
2848         int error;
2849         char *context = NULL;
2850         struct inode_security_struct *isec = inode->i_security;
2851
2852         if (strcmp(name, XATTR_SELINUX_SUFFIX))
2853                 return -EOPNOTSUPP;
2854
2855         /*
2856          * If the caller has CAP_MAC_ADMIN, then get the raw context
2857          * value even if it is not defined by current policy; otherwise,
2858          * use the in-core value under current policy.
2859          * Use the non-auditing forms of the permission checks since
2860          * getxattr may be called by unprivileged processes commonly
2861          * and lack of permission just means that we fall back to the
2862          * in-core context value, not a denial.
2863          */
2864         error = selinux_capable(current, current_cred(), CAP_MAC_ADMIN,
2865                                 SECURITY_CAP_NOAUDIT);
2866         if (!error)
2867                 error = security_sid_to_context_force(isec->sid, &context,
2868                                                       &size);
2869         else
2870                 error = security_sid_to_context(isec->sid, &context, &size);
2871         if (error)
2872                 return error;
2873         error = size;
2874         if (alloc) {
2875                 *buffer = context;
2876                 goto out_nofree;
2877         }
2878         kfree(context);
2879 out_nofree:
2880         return error;
2881 }
2882
2883 static int selinux_inode_setsecurity(struct inode *inode, const char *name,
2884                                      const void *value, size_t size, int flags)
2885 {
2886         struct inode_security_struct *isec = inode->i_security;
2887         u32 newsid;
2888         int rc;
2889
2890         if (strcmp(name, XATTR_SELINUX_SUFFIX))
2891                 return -EOPNOTSUPP;
2892
2893         if (!value || !size)
2894                 return -EACCES;
2895
2896         rc = security_context_to_sid((void *)value, size, &newsid);
2897         if (rc)
2898                 return rc;
2899
2900         isec->sid = newsid;
2901         return 0;
2902 }
2903
2904 static int selinux_inode_listsecurity(struct inode *inode, char *buffer, size_t buffer_size)
2905 {
2906         const int len = sizeof(XATTR_NAME_SELINUX);
2907         if (buffer && len <= buffer_size)
2908                 memcpy(buffer, XATTR_NAME_SELINUX, len);
2909         return len;
2910 }
2911
2912 static int selinux_inode_need_killpriv(struct dentry *dentry)
2913 {
2914         return secondary_ops->inode_need_killpriv(dentry);
2915 }
2916
2917 static int selinux_inode_killpriv(struct dentry *dentry)
2918 {
2919         return secondary_ops->inode_killpriv(dentry);
2920 }
2921
2922 static void selinux_inode_getsecid(const struct inode *inode, u32 *secid)
2923 {
2924         struct inode_security_struct *isec = inode->i_security;
2925         *secid = isec->sid;
2926 }
2927
2928 /* file security operations */
2929
2930 static int selinux_revalidate_file_permission(struct file *file, int mask)
2931 {
2932         const struct cred *cred = current_cred();
2933         int rc;
2934         struct inode *inode = file->f_path.dentry->d_inode;
2935
2936         if (!mask) {
2937                 /* No permission to check.  Existence test. */
2938                 return 0;
2939         }
2940
2941         /* file_mask_to_av won't add FILE__WRITE if MAY_APPEND is set */
2942         if ((file->f_flags & O_APPEND) && (mask & MAY_WRITE))
2943                 mask |= MAY_APPEND;
2944
2945         rc = file_has_perm(cred, file,
2946                            file_mask_to_av(inode->i_mode, mask));
2947         if (rc)
2948                 return rc;
2949
2950         return selinux_netlbl_inode_permission(inode, mask);
2951 }
2952
2953 static int selinux_file_permission(struct file *file, int mask)
2954 {
2955         struct inode *inode = file->f_path.dentry->d_inode;
2956         struct file_security_struct *fsec = file->f_security;
2957         struct inode_security_struct *isec = inode->i_security;
2958         u32 sid = current_sid();
2959
2960         if (!mask) {
2961                 /* No permission to check.  Existence test. */
2962                 return 0;
2963         }
2964
2965         if (sid == fsec->sid && fsec->isid == isec->sid
2966             && fsec->pseqno == avc_policy_seqno())
2967                 return selinux_netlbl_inode_permission(inode, mask);
2968
2969         return selinux_revalidate_file_permission(file, mask);
2970 }
2971
2972 static int selinux_file_alloc_security(struct file *file)
2973 {
2974         return file_alloc_security(file);
2975 }
2976
2977 static void selinux_file_free_security(struct file *file)
2978 {
2979         file_free_security(file);
2980 }
2981
2982 static int selinux_file_ioctl(struct file *file, unsigned int cmd,
2983                               unsigned long arg)
2984 {
2985         const struct cred *cred = current_cred();
2986         u32 av = 0;
2987
2988         if (_IOC_DIR(cmd) & _IOC_WRITE)
2989                 av |= FILE__WRITE;
2990         if (_IOC_DIR(cmd) & _IOC_READ)
2991                 av |= FILE__READ;
2992         if (!av)
2993                 av = FILE__IOCTL;
2994
2995         return file_has_perm(cred, file, av);
2996 }
2997
2998 static int file_map_prot_check(struct file *file, unsigned long prot, int shared)
2999 {
3000         const struct cred *cred = current_cred();
3001         int rc = 0;
3002
3003 #ifndef CONFIG_PPC32
3004         if ((prot & PROT_EXEC) && (!file || (!shared && (prot & PROT_WRITE)))) {
3005                 /*
3006                  * We are making executable an anonymous mapping or a
3007                  * private file mapping that will also be writable.
3008                  * This has an additional check.
3009                  */
3010                 rc = cred_has_perm(cred, cred, PROCESS__EXECMEM);
3011                 if (rc)
3012                         goto error;
3013         }
3014 #endif
3015
3016         if (file) {
3017                 /* read access is always possible with a mapping */
3018                 u32 av = FILE__READ;
3019
3020                 /* write access only matters if the mapping is shared */
3021                 if (shared && (prot & PROT_WRITE))
3022                         av |= FILE__WRITE;
3023
3024                 if (prot & PROT_EXEC)
3025                         av |= FILE__EXECUTE;
3026
3027                 return file_has_perm(cred, file, av);
3028         }
3029
3030 error:
3031         return rc;
3032 }
3033
3034 static int selinux_file_mmap(struct file *file, unsigned long reqprot,
3035                              unsigned long prot, unsigned long flags,
3036                              unsigned long addr, unsigned long addr_only)
3037 {
3038         int rc = 0;
3039         u32 sid = current_sid();
3040
3041         if (addr < mmap_min_addr)
3042                 rc = avc_has_perm(sid, sid, SECCLASS_MEMPROTECT,
3043                                   MEMPROTECT__MMAP_ZERO, NULL);
3044         if (rc || addr_only)
3045                 return rc;
3046
3047         if (selinux_checkreqprot)
3048                 prot = reqprot;
3049
3050         return file_map_prot_check(file, prot,
3051                                    (flags & MAP_TYPE) == MAP_SHARED);
3052 }
3053
3054 static int selinux_file_mprotect(struct vm_area_struct *vma,
3055                                  unsigned long reqprot,
3056                                  unsigned long prot)
3057 {
3058         const struct cred *cred = current_cred();
3059
3060         if (selinux_checkreqprot)
3061                 prot = reqprot;
3062
3063 #ifndef CONFIG_PPC32
3064         if ((prot & PROT_EXEC) && !(vma->vm_flags & VM_EXEC)) {
3065                 int rc = 0;
3066                 if (vma->vm_start >= vma->vm_mm->start_brk &&
3067                     vma->vm_end <= vma->vm_mm->brk) {
3068                         rc = cred_has_perm(cred, cred, PROCESS__EXECHEAP);
3069                 } else if (!vma->vm_file &&
3070                            vma->vm_start <= vma->vm_mm->start_stack &&
3071                            vma->vm_end >= vma->vm_mm->start_stack) {
3072                         rc = current_has_perm(current, PROCESS__EXECSTACK);
3073                 } else if (vma->vm_file && vma->anon_vma) {
3074                         /*
3075                          * We are making executable a file mapping that has
3076                          * had some COW done. Since pages might have been
3077                          * written, check ability to execute the possibly
3078                          * modified content.  This typically should only
3079                          * occur for text relocations.
3080                          */
3081                         rc = file_has_perm(cred, vma->vm_file, FILE__EXECMOD);
3082                 }
3083                 if (rc)
3084                         return rc;
3085         }
3086 #endif
3087
3088         return file_map_prot_check(vma->vm_file, prot, vma->vm_flags&VM_SHARED);
3089 }
3090
3091 static int selinux_file_lock(struct file *file, unsigned int cmd)
3092 {
3093         const struct cred *cred = current_cred();
3094
3095         return file_has_perm(cred, file, FILE__LOCK);
3096 }
3097
3098 static int selinux_file_fcntl(struct file *file, unsigned int cmd,
3099                               unsigned long arg)
3100 {
3101         const struct cred *cred = current_cred();
3102         int err = 0;
3103
3104         switch (cmd) {
3105         case F_SETFL:
3106                 if (!file->f_path.dentry || !file->f_path.dentry->d_inode) {
3107                         err = -EINVAL;
3108                         break;
3109                 }
3110
3111                 if ((file->f_flags & O_APPEND) && !(arg & O_APPEND)) {
3112                         err = file_has_perm(cred, file, FILE__WRITE);
3113                         break;
3114                 }
3115                 /* fall through */
3116         case F_SETOWN:
3117         case F_SETSIG:
3118         case F_GETFL:
3119         case F_GETOWN:
3120         case F_GETSIG:
3121                 /* Just check FD__USE permission */
3122                 err = file_has_perm(cred, file, 0);
3123                 break;
3124         case F_GETLK:
3125         case F_SETLK:
3126         case F_SETLKW:
3127 #if BITS_PER_LONG == 32
3128         case F_GETLK64:
3129         case F_SETLK64:
3130         case F_SETLKW64:
3131 #endif
3132                 if (!file->f_path.dentry || !file->f_path.dentry->d_inode) {
3133                         err = -EINVAL;
3134                         break;
3135                 }
3136                 err = file_has_perm(cred, file, FILE__LOCK);
3137                 break;
3138         }
3139
3140         return err;
3141 }
3142
3143 static int selinux_file_set_fowner(struct file *file)
3144 {
3145         struct file_security_struct *fsec;
3146
3147         fsec = file->f_security;
3148         fsec->fown_sid = current_sid();
3149
3150         return 0;
3151 }
3152
3153 static int selinux_file_send_sigiotask(struct task_struct *tsk,
3154                                        struct fown_struct *fown, int signum)
3155 {
3156         struct file *file;
3157         u32 sid = current_sid();
3158         u32 perm;
3159         struct file_security_struct *fsec;
3160
3161         /* struct fown_struct is never outside the context of a struct file */
3162         file = container_of(fown, struct file, f_owner);
3163
3164         fsec = file->f_security;
3165
3166         if (!signum)
3167                 perm = signal_to_av(SIGIO); /* as per send_sigio_to_task */
3168         else
3169                 perm = signal_to_av(signum);
3170
3171         return avc_has_perm(fsec->fown_sid, sid,
3172                             SECCLASS_PROCESS, perm, NULL);
3173 }
3174
3175 static int selinux_file_receive(struct file *file)
3176 {
3177         const struct cred *cred = current_cred();
3178
3179         return file_has_perm(cred, file, file_to_av(file));
3180 }
3181
3182 static int selinux_dentry_open(struct file *file, const struct cred *cred)
3183 {
3184         struct file_security_struct *fsec;
3185         struct inode *inode;
3186         struct inode_security_struct *isec;
3187
3188         inode = file->f_path.dentry->d_inode;
3189         fsec = file->f_security;
3190         isec = inode->i_security;
3191         /*
3192          * Save inode label and policy sequence number
3193          * at open-time so that selinux_file_permission
3194          * can determine whether revalidation is necessary.
3195          * Task label is already saved in the file security
3196          * struct as its SID.
3197          */
3198         fsec->isid = isec->sid;
3199         fsec->pseqno = avc_policy_seqno();
3200         /*
3201          * Since the inode label or policy seqno may have changed
3202          * between the selinux_inode_permission check and the saving
3203          * of state above, recheck that access is still permitted.
3204          * Otherwise, access might never be revalidated against the
3205          * new inode label or new policy.
3206          * This check is not redundant - do not remove.
3207          */
3208         return inode_has_perm(cred, inode, open_file_to_av(file), NULL);
3209 }
3210
3211 /* task security operations */
3212
3213 static int selinux_task_create(unsigned long clone_flags)
3214 {
3215         return current_has_perm(current, PROCESS__FORK);
3216 }
3217
3218 /*
3219  * detach and free the LSM part of a set of credentials
3220  */
3221 static void selinux_cred_free(struct cred *cred)
3222 {
3223         struct task_security_struct *tsec = cred->security;
3224         cred->security = NULL;
3225         kfree(tsec);
3226 }
3227
3228 /*
3229  * prepare a new set of credentials for modification
3230  */
3231 static int selinux_cred_prepare(struct cred *new, const struct cred *old,
3232                                 gfp_t gfp)
3233 {
3234         const struct task_security_struct *old_tsec;
3235         struct task_security_struct *tsec;
3236
3237         old_tsec = old->security;
3238
3239         tsec = kmemdup(old_tsec, sizeof(struct task_security_struct), gfp);
3240         if (!tsec)
3241                 return -ENOMEM;
3242
3243         new->security = tsec;
3244         return 0;
3245 }
3246
3247 /*
3248  * commit new credentials
3249  */
3250 static void selinux_cred_commit(struct cred *new, const struct cred *old)
3251 {
3252         secondary_ops->cred_commit(new, old);
3253 }
3254
3255 /*
3256  * set the security data for a kernel service
3257  * - all the creation contexts are set to unlabelled
3258  */
3259 static int selinux_kernel_act_as(struct cred *new, u32 secid)
3260 {
3261         struct task_security_struct *tsec = new->security;
3262         u32 sid = current_sid();
3263         int ret;
3264
3265         ret = avc_has_perm(sid, secid,
3266                            SECCLASS_KERNEL_SERVICE,
3267                            KERNEL_SERVICE__USE_AS_OVERRIDE,
3268                            NULL);
3269         if (ret == 0) {
3270                 tsec->sid = secid;
3271                 tsec->create_sid = 0;
3272                 tsec->keycreate_sid = 0;
3273                 tsec->sockcreate_sid = 0;
3274         }
3275         return ret;
3276 }
3277
3278 /*
3279  * set the file creation context in a security record to the same as the
3280  * objective context of the specified inode
3281  */
3282 static int selinux_kernel_create_files_as(struct cred *new, struct inode *inode)
3283 {
3284         struct inode_security_struct *isec = inode->i_security;
3285         struct task_security_struct *tsec = new->security;
3286         u32 sid = current_sid();
3287         int ret;
3288
3289         ret = avc_has_perm(sid, isec->sid,
3290                            SECCLASS_KERNEL_SERVICE,
3291                            KERNEL_SERVICE__CREATE_FILES_AS,
3292                            NULL);
3293
3294         if (ret == 0)
3295                 tsec->create_sid = isec->sid;
3296         return 0;
3297 }
3298
3299 static int selinux_task_setuid(uid_t id0, uid_t id1, uid_t id2, int flags)
3300 {
3301         /* Since setuid only affects the current process, and
3302            since the SELinux controls are not based on the Linux
3303            identity attributes, SELinux does not need to control
3304            this operation.  However, SELinux does control the use
3305            of the CAP_SETUID and CAP_SETGID capabilities using the
3306            capable hook. */
3307         return 0;
3308 }
3309
3310 static int selinux_task_fix_setuid(struct cred *new, const struct cred *old,
3311                                    int flags)
3312 {
3313         return secondary_ops->task_fix_setuid(new, old, flags);
3314 }
3315
3316 static int selinux_task_setgid(gid_t id0, gid_t id1, gid_t id2, int flags)
3317 {
3318         /* See the comment for setuid above. */
3319         return 0;
3320 }
3321
3322 static int selinux_task_setpgid(struct task_struct *p, pid_t pgid)
3323 {
3324         return current_has_perm(p, PROCESS__SETPGID);
3325 }
3326
3327 static int selinux_task_getpgid(struct task_struct *p)
3328 {
3329         return current_has_perm(p, PROCESS__GETPGID);
3330 }
3331
3332 static int selinux_task_getsid(struct task_struct *p)
3333 {
3334         return current_has_perm(p, PROCESS__GETSESSION);
3335 }
3336
3337 static void selinux_task_getsecid(struct task_struct *p, u32 *secid)
3338 {
3339         *secid = task_sid(p);
3340 }
3341
3342 static int selinux_task_setgroups(struct group_info *group_info)
3343 {
3344         /* See the comment for setuid above. */
3345         return 0;
3346 }
3347
3348 static int selinux_task_setnice(struct task_struct *p, int nice)
3349 {
3350         int rc;
3351
3352         rc = secondary_ops->task_setnice(p, nice);
3353         if (rc)
3354                 return rc;
3355
3356         return current_has_perm(p, PROCESS__SETSCHED);
3357 }
3358
3359 static int selinux_task_setioprio(struct task_struct *p, int ioprio)
3360 {
3361         int rc;
3362
3363         rc = secondary_ops->task_setioprio(p, ioprio);
3364         if (rc)
3365                 return rc;
3366
3367         return current_has_perm(p, PROCESS__SETSCHED);
3368 }
3369
3370 static int selinux_task_getioprio(struct task_struct *p)
3371 {
3372         return current_has_perm(p, PROCESS__GETSCHED);
3373 }
3374
3375 static int selinux_task_setrlimit(unsigned int resource, struct rlimit *new_rlim)
3376 {
3377         struct rlimit *old_rlim = current->signal->rlim + resource;
3378         int rc;
3379
3380         rc = secondary_ops->task_setrlimit(resource, new_rlim);
3381         if (rc)
3382                 return rc;
3383
3384         /* Control the ability to change the hard limit (whether
3385            lowering or raising it), so that the hard limit can
3386            later be used as a safe reset point for the soft limit
3387            upon context transitions.  See selinux_bprm_committing_creds. */
3388         if (old_rlim->rlim_max != new_rlim->rlim_max)
3389                 return current_has_perm(current, PROCESS__SETRLIMIT);
3390
3391         return 0;
3392 }
3393
3394 static int selinux_task_setscheduler(struct task_struct *p, int policy, struct sched_param *lp)
3395 {
3396         int rc;
3397
3398         rc = secondary_ops->task_setscheduler(p, policy, lp);
3399         if (rc)
3400                 return rc;
3401
3402         return current_has_perm(p, PROCESS__SETSCHED);
3403 }
3404
3405 static int selinux_task_getscheduler(struct task_struct *p)
3406 {
3407         return current_has_perm(p, PROCESS__GETSCHED);
3408 }
3409
3410 static int selinux_task_movememory(struct task_struct *p)
3411 {
3412         return current_has_perm(p, PROCESS__SETSCHED);
3413 }
3414
3415 static int selinux_task_kill(struct task_struct *p, struct siginfo *info,
3416                                 int sig, u32 secid)
3417 {
3418         u32 perm;
3419         int rc;
3420
3421         rc = secondary_ops->task_kill(p, info, sig, secid);
3422         if (rc)
3423                 return rc;
3424
3425         if (!sig)
3426                 perm = PROCESS__SIGNULL; /* null signal; existence test */
3427         else
3428                 perm = signal_to_av(sig);
3429         if (secid)
3430                 rc = avc_has_perm(secid, task_sid(p),
3431                                   SECCLASS_PROCESS, perm, NULL);
3432         else
3433                 rc = current_has_perm(p, perm);
3434         return rc;
3435 }
3436
3437 static int selinux_task_prctl(int option,
3438                               unsigned long arg2,
3439                               unsigned long arg3,
3440                               unsigned long arg4,
3441                               unsigned long arg5)
3442 {
3443         /* The current prctl operations do not appear to require
3444            any SELinux controls since they merely observe or modify
3445            the state of the current process. */
3446         return secondary_ops->task_prctl(option, arg2, arg3, arg4, arg5);
3447 }
3448
3449 static int selinux_task_wait(struct task_struct *p)
3450 {
3451         return task_has_perm(p, current, PROCESS__SIGCHLD);
3452 }
3453
3454 static void selinux_task_to_inode(struct task_struct *p,
3455                                   struct inode *inode)
3456 {
3457         struct inode_security_struct *isec = inode->i_security;
3458         u32 sid = task_sid(p);
3459
3460         isec->sid = sid;
3461         isec->initialized = 1;
3462 }
3463
3464 /* Returns error only if unable to parse addresses */
3465 static int selinux_parse_skb_ipv4(struct sk_buff *skb,
3466                         struct avc_audit_data *ad, u8 *proto)
3467 {
3468         int offset, ihlen, ret = -EINVAL;
3469         struct iphdr _iph, *ih;
3470
3471         offset = skb_network_offset(skb);
3472         ih = skb_header_pointer(skb, offset, sizeof(_iph), &_iph);
3473         if (ih == NULL)
3474                 goto out;
3475
3476         ihlen = ih->ihl * 4;
3477         if (ihlen < sizeof(_iph))
3478                 goto out;
3479
3480         ad->u.net.v4info.saddr = ih->saddr;
3481         ad->u.net.v4info.daddr = ih->daddr;
3482         ret = 0;
3483
3484         if (proto)
3485                 *proto = ih->protocol;
3486
3487         switch (ih->protocol) {
3488         case IPPROTO_TCP: {
3489                 struct tcphdr _tcph, *th;
3490
3491                 if (ntohs(ih->frag_off) & IP_OFFSET)
3492                         break;
3493
3494                 offset += ihlen;
3495                 th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph);
3496                 if (th == NULL)
3497                         break;
3498
3499                 ad->u.net.sport = th->source;
3500                 ad->u.net.dport = th->dest;
3501                 break;
3502         }
3503
3504         case IPPROTO_UDP: {
3505                 struct udphdr _udph, *uh;
3506
3507                 if (ntohs(ih->frag_off) & IP_OFFSET)
3508                         break;
3509
3510                 offset += ihlen;
3511                 uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph);
3512                 if (uh == NULL)
3513                         break;
3514
3515                 ad->u.net.sport = uh->source;
3516                 ad->u.net.dport = uh->dest;
3517                 break;
3518         }
3519
3520         case IPPROTO_DCCP: {
3521                 struct dccp_hdr _dccph, *dh;
3522
3523                 if (ntohs(ih->frag_off) & IP_OFFSET)
3524                         break;
3525
3526                 offset += ihlen;
3527                 dh = skb_header_pointer(skb, offset, sizeof(_dccph), &_dccph);
3528                 if (dh == NULL)
3529                         break;
3530
3531                 ad->u.net.sport = dh->dccph_sport;
3532                 ad->u.net.dport = dh->dccph_dport;
3533                 break;
3534         }
3535
3536         default:
3537                 break;
3538         }
3539 out:
3540         return ret;
3541 }
3542
3543 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
3544
3545 /* Returns error only if unable to parse addresses */
3546 static int selinux_parse_skb_ipv6(struct sk_buff *skb,
3547                         struct avc_audit_data *ad, u8 *proto)
3548 {
3549         u8 nexthdr;
3550         int ret = -EINVAL, offset;
3551         struct ipv6hdr _ipv6h, *ip6;
3552
3553         offset = skb_network_offset(skb);
3554         ip6 = skb_header_pointer(skb, offset, sizeof(_ipv6h), &_ipv6h);
3555         if (ip6 == NULL)
3556                 goto out;
3557
3558         ipv6_addr_copy(&ad->u.net.v6info.saddr, &ip6->saddr);
3559         ipv6_addr_copy(&ad->u.net.v6info.daddr, &ip6->daddr);
3560         ret = 0;
3561
3562         nexthdr = ip6->nexthdr;
3563         offset += sizeof(_ipv6h);
3564         offset = ipv6_skip_exthdr(skb, offset, &nexthdr);
3565         if (offset < 0)
3566                 goto out;
3567
3568         if (proto)
3569                 *proto = nexthdr;
3570
3571         switch (nexthdr) {
3572         case IPPROTO_TCP: {
3573                 struct tcphdr _tcph, *th;
3574
3575                 th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph);
3576                 if (th == NULL)
3577                         break;
3578
3579                 ad->u.net.sport = th->source;
3580                 ad->u.net.dport = th->dest;
3581                 break;
3582         }
3583
3584         case IPPROTO_UDP: {
3585                 struct udphdr _udph, *uh;
3586
3587                 uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph);
3588                 if (uh == NULL)
3589                         break;
3590
3591                 ad->u.net.sport = uh->source;
3592                 ad->u.net.dport = uh->dest;
3593                 break;
3594         }
3595
3596         case IPPROTO_DCCP: {
3597                 struct dccp_hdr _dccph, *dh;
3598
3599                 dh = skb_header_pointer(skb, offset, sizeof(_dccph), &_dccph);
3600                 if (dh == NULL)
3601                         break;
3602
3603                 ad->u.net.sport = dh->dccph_sport;
3604                 ad->u.net.dport = dh->dccph_dport;
3605                 break;
3606         }
3607
3608         /* includes fragments */
3609         default:
3610                 break;
3611         }
3612 out:
3613         return ret;
3614 }
3615
3616 #endif /* IPV6 */
3617
3618 static int selinux_parse_skb(struct sk_buff *skb, struct avc_audit_data *ad,
3619                              char **_addrp, int src, u8 *proto)
3620 {
3621         char *addrp;
3622         int ret;
3623
3624         switch (ad->u.net.family) {
3625         case PF_INET:
3626                 ret = selinux_parse_skb_ipv4(skb, ad, proto);
3627                 if (ret)
3628                         goto parse_error;
3629                 addrp = (char *)(src ? &ad->u.net.v4info.saddr :
3630                                        &ad->u.net.v4info.daddr);
3631                 goto okay;
3632
3633 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
3634         case PF_INET6:
3635                 ret = selinux_parse_skb_ipv6(skb, ad, proto);
3636                 if (ret)
3637                         goto parse_error;
3638                 addrp = (char *)(src ? &ad->u.net.v6info.saddr :
3639                                        &ad->u.net.v6info.daddr);
3640                 goto okay;
3641 #endif  /* IPV6 */
3642         default:
3643                 addrp = NULL;
3644                 goto okay;
3645         }
3646
3647 parse_error:
3648         printk(KERN_WARNING
3649                "SELinux: failure in selinux_parse_skb(),"
3650                " unable to parse packet\n");
3651         return ret;
3652
3653 okay:
3654         if (_addrp)
3655                 *_addrp = addrp;
3656         return 0;
3657 }
3658
3659 /**
3660  * selinux_skb_peerlbl_sid - Determine the peer label of a packet
3661  * @skb: the packet
3662  * @family: protocol family
3663  * @sid: the packet's peer label SID
3664  *
3665  * Description:
3666  * Check the various different forms of network peer labeling and determine
3667  * the peer label/SID for the packet; most of the magic actually occurs in
3668  * the security server function security_net_peersid_cmp().  The function
3669  * returns zero if the value in @sid is valid (although it may be SECSID_NULL)
3670  * or -EACCES if @sid is invalid due to inconsistencies with the different
3671  * peer labels.
3672  *
3673  */
3674 static int selinux_skb_peerlbl_sid(struct sk_buff *skb, u16 family, u32 *sid)
3675 {
3676         int err;
3677         u32 xfrm_sid;
3678         u32 nlbl_sid;
3679         u32 nlbl_type;
3680
3681         selinux_skb_xfrm_sid(skb, &xfrm_sid);
3682         selinux_netlbl_skbuff_getsid(skb, family, &nlbl_type, &nlbl_sid);
3683
3684         err = security_net_peersid_resolve(nlbl_sid, nlbl_type, xfrm_sid, sid);
3685         if (unlikely(err)) {
3686                 printk(KERN_WARNING
3687                        "SELinux: failure in selinux_skb_peerlbl_sid(),"
3688                        " unable to determine packet's peer label\n");
3689                 return -EACCES;
3690         }
3691
3692         return 0;
3693 }
3694
3695 /* socket security operations */
3696 static int socket_has_perm(struct task_struct *task, struct socket *sock,
3697                            u32 perms)
3698 {
3699         struct inode_security_struct *isec;
3700         struct avc_audit_data ad;
3701         u32 sid;
3702         int err = 0;
3703
3704         isec = SOCK_INODE(sock)->i_security;
3705
3706         if (isec->sid == SECINITSID_KERNEL)
3707                 goto out;
3708         sid = task_sid(task);
3709
3710         AVC_AUDIT_DATA_INIT(&ad, NET);
3711         ad.u.net.sk = sock->sk;
3712         err = avc_has_perm(sid, isec->sid, isec->sclass, perms, &ad);
3713
3714 out:
3715         return err;
3716 }
3717
3718 static int selinux_socket_create(int family, int type,
3719                                  int protocol, int kern)
3720 {
3721         const struct cred *cred = current_cred();
3722         const struct task_security_struct *tsec = cred->security;
3723         u32 sid, newsid;
3724         u16 secclass;
3725         int err = 0;
3726
3727         if (kern)
3728                 goto out;
3729
3730         sid = tsec->sid;
3731         newsid = tsec->sockcreate_sid ?: sid;
3732
3733         secclass = socket_type_to_security_class(family, type, protocol);
3734         err = avc_has_perm(sid, newsid, secclass, SOCKET__CREATE, NULL);
3735
3736 out:
3737         return err;
3738 }
3739
3740 static int selinux_socket_post_create(struct socket *sock, int family,
3741                                       int type, int protocol, int kern)
3742 {
3743         const struct cred *cred = current_cred();
3744         const struct task_security_struct *tsec = cred->security;
3745         struct inode_security_struct *isec;
3746         struct sk_security_struct *sksec;
3747         u32 sid, newsid;
3748         int err = 0;
3749
3750         sid = tsec->sid;
3751         newsid = tsec->sockcreate_sid;
3752
3753         isec = SOCK_INODE(sock)->i_security;
3754
3755         if (kern)
3756                 isec->sid = SECINITSID_KERNEL;
3757         else if (newsid)
3758                 isec->sid = newsid;
3759         else
3760                 isec->sid = sid;
3761
3762         isec->sclass = socket_type_to_security_class(family, type, protocol);
3763         isec->initialized = 1;
3764
3765         if (sock->sk) {
3766                 sksec = sock->sk->sk_security;
3767                 sksec->sid = isec->sid;
3768                 sksec->sclass = isec->sclass;
3769                 err = selinux_netlbl_socket_post_create(sock);
3770         }
3771
3772         return err;
3773 }
3774
3775 /* Range of port numbers used to automatically bind.
3776    Need to determine whether we should perform a name_bind
3777    permission check between the socket and the port number. */
3778
3779 static int selinux_socket_bind(struct socket *sock, struct sockaddr *address, int addrlen)
3780 {
3781         u16 family;
3782         int err;
3783
3784         err = socket_has_perm(current, sock, SOCKET__BIND);
3785         if (err)
3786                 goto out;
3787
3788         /*
3789          * If PF_INET or PF_INET6, check name_bind permission for the port.
3790          * Multiple address binding for SCTP is not supported yet: we just
3791          * check the first address now.
3792          */
3793         family = sock->sk->sk_family;
3794         if (family == PF_INET || family == PF_INET6) {
3795                 char *addrp;
3796                 struct inode_security_struct *isec;
3797                 struct avc_audit_data ad;
3798                 struct sockaddr_in *addr4 = NULL;
3799                 struct sockaddr_in6 *addr6 = NULL;
3800                 unsigned short snum;
3801                 struct sock *sk = sock->sk;
3802                 u32 sid, node_perm;
3803
3804                 isec = SOCK_INODE(sock)->i_security;
3805
3806                 if (family == PF_INET) {
3807                         addr4 = (struct sockaddr_in *)address;
3808                         snum = ntohs(addr4->sin_port);
3809                         addrp = (char *)&addr4->sin_addr.s_addr;
3810                 } else {
3811                         addr6 = (struct sockaddr_in6 *)address;
3812                         snum = ntohs(addr6->sin6_port);
3813                         addrp = (char *)&addr6->sin6_addr.s6_addr;
3814                 }
3815
3816                 if (snum) {
3817                         int low, high;
3818
3819                         inet_get_local_port_range(&low, &high);
3820
3821                         if (snum < max(PROT_SOCK, low) || snum > high) {
3822                                 err = sel_netport_sid(sk->sk_protocol,
3823                                                       snum, &sid);
3824                                 if (err)
3825                                         goto out;
3826                                 AVC_AUDIT_DATA_INIT(&ad, NET);
3827                                 ad.u.net.sport = htons(snum);
3828                                 ad.u.net.family = family;
3829                                 err = avc_has_perm(isec->sid, sid,
3830                                                    isec->sclass,
3831                                                    SOCKET__NAME_BIND, &ad);
3832                                 if (err)
3833                                         goto out;
3834                         }
3835                 }
3836
3837                 switch (isec->sclass) {
3838                 case SECCLASS_TCP_SOCKET:
3839                         node_perm = TCP_SOCKET__NODE_BIND;
3840                         break;
3841
3842                 case SECCLASS_UDP_SOCKET:
3843                         node_perm = UDP_SOCKET__NODE_BIND;
3844                         break;
3845
3846                 case SECCLASS_DCCP_SOCKET:
3847                         node_perm = DCCP_SOCKET__NODE_BIND;
3848                         break;
3849
3850                 default:
3851                         node_perm = RAWIP_SOCKET__NODE_BIND;
3852                         break;
3853                 }
3854
3855                 err = sel_netnode_sid(addrp, family, &sid);
3856                 if (err)
3857                         goto out;
3858
3859                 AVC_AUDIT_DATA_INIT(&ad, NET);
3860                 ad.u.net.sport = htons(snum);
3861                 ad.u.net.family = family;
3862
3863                 if (family == PF_INET)
3864                         ad.u.net.v4info.saddr = addr4->sin_addr.s_addr;
3865                 else
3866                         ipv6_addr_copy(&ad.u.net.v6info.saddr, &addr6->sin6_addr);
3867
3868                 err = avc_has_perm(isec->sid, sid,
3869                                    isec->sclass, node_perm, &ad);
3870                 if (err)
3871                         goto out;
3872         }
3873 out:
3874         return err;
3875 }
3876
3877 static int selinux_socket_connect(struct socket *sock, struct sockaddr *address, int addrlen)
3878 {
3879         struct sock *sk = sock->sk;
3880         struct inode_security_struct *isec;
3881         int err;
3882
3883         err = socket_has_perm(current, sock, SOCKET__CONNECT);
3884         if (err)
3885                 return err;
3886
3887         /*
3888          * If a TCP or DCCP socket, check name_connect permission for the port.
3889          */
3890         isec = SOCK_INODE(sock)->i_security;
3891         if (isec->sclass == SECCLASS_TCP_SOCKET ||
3892             isec->sclass == SECCLASS_DCCP_SOCKET) {
3893                 struct avc_audit_data ad;
3894                 struct sockaddr_in *addr4 = NULL;
3895                 struct sockaddr_in6 *addr6 = NULL;
3896                 unsigned short snum;
3897                 u32 sid, perm;
3898
3899                 if (sk->sk_family == PF_INET) {
3900                         addr4 = (struct sockaddr_in *)address;
3901                         if (addrlen < sizeof(struct sockaddr_in))
3902                                 return -EINVAL;
3903                         snum = ntohs(addr4->sin_port);
3904                 } else {
3905                         addr6 = (struct sockaddr_in6 *)address;
3906                         if (addrlen < SIN6_LEN_RFC2133)
3907                                 return -EINVAL;
3908                         snum = ntohs(addr6->sin6_port);
3909                 }
3910
3911                 err = sel_netport_sid(sk->sk_protocol, snum, &sid);
3912                 if (err)
3913                         goto out;
3914
3915                 perm = (isec->sclass == SECCLASS_TCP_SOCKET) ?
3916                        TCP_SOCKET__NAME_CONNECT : DCCP_SOCKET__NAME_CONNECT;
3917
3918                 AVC_AUDIT_DATA_INIT(&ad, NET);
3919                 ad.u.net.dport = htons(snum);
3920                 ad.u.net.family = sk->sk_family;
3921                 err = avc_has_perm(isec->sid, sid, isec->sclass, perm, &ad);
3922                 if (err)
3923                         goto out;
3924         }
3925
3926         err = selinux_netlbl_socket_connect(sk, address);
3927
3928 out:
3929         return err;
3930 }
3931
3932 static int selinux_socket_listen(struct socket *sock, int backlog)
3933 {
3934         return socket_has_perm(current, sock, SOCKET__LISTEN);
3935 }
3936
3937 static int selinux_socket_accept(struct socket *sock, struct socket *newsock)
3938 {
3939         int err;
3940         struct inode_security_struct *isec;
3941         struct inode_security_struct *newisec;
3942
3943         err = socket_has_perm(current, sock, SOCKET__ACCEPT);
3944         if (err)
3945                 return err;
3946
3947         newisec = SOCK_INODE(newsock)->i_security;
3948
3949         isec = SOCK_INODE(sock)->i_security;
3950         newisec->sclass = isec->sclass;
3951         newisec->sid = isec->sid;
3952         newisec->initialized = 1;
3953
3954         return 0;
3955 }
3956
3957 static int selinux_socket_sendmsg(struct socket *sock, struct msghdr *msg,
3958                                   int size)
3959 {
3960         int rc;
3961
3962         rc = socket_has_perm(current, sock, SOCKET__WRITE);
3963         if (rc)
3964                 return rc;
3965
3966         return selinux_netlbl_inode_permission(SOCK_INODE(sock), MAY_WRITE);
3967 }
3968
3969 static int selinux_socket_recvmsg(struct socket *sock, struct msghdr *msg,
3970                                   int size, int flags)
3971 {
3972         return socket_has_perm(current, sock, SOCKET__READ);
3973 }
3974
3975 static int selinux_socket_getsockname(struct socket *sock)
3976 {
3977         return socket_has_perm(current, sock, SOCKET__GETATTR);
3978 }
3979
3980 static int selinux_socket_getpeername(struct socket *sock)
3981 {
3982         return socket_has_perm(current, sock, SOCKET__GETATTR);
3983 }
3984
3985 static int selinux_socket_setsockopt(struct socket *sock, int level, int optname)
3986 {
3987         int err;
3988
3989         err = socket_has_perm(current, sock, SOCKET__SETOPT);
3990         if (err)
3991                 return err;
3992
3993         return selinux_netlbl_socket_setsockopt(sock, level, optname);
3994 }
3995
3996 static int selinux_socket_getsockopt(struct socket *sock, int level,
3997                                      int optname)
3998 {
3999         return socket_has_perm(current, sock, SOCKET__GETOPT);
4000 }
4001
4002 static int selinux_socket_shutdown(struct socket *sock, int how)
4003 {
4004         return socket_has_perm(current, sock, SOCKET__SHUTDOWN);
4005 }
4006
4007 static int selinux_socket_unix_stream_connect(struct socket *sock,
4008                                               struct socket *other,
4009                                               struct sock *newsk)
4010 {
4011         struct sk_security_struct *ssec;
4012         struct inode_security_struct *isec;
4013         struct inode_security_struct *other_isec;
4014         struct avc_audit_data ad;
4015         int err;
4016
4017         err = secondary_ops->unix_stream_connect(sock, other, newsk);
4018         if (err)
4019                 return err;
4020
4021         isec = SOCK_INODE(sock)->i_security;
4022         other_isec = SOCK_INODE(other)->i_security;
4023
4024         AVC_AUDIT_DATA_INIT(&ad, NET);
4025         ad.u.net.sk = other->sk;
4026
4027         err = avc_has_perm(isec->sid, other_isec->sid,
4028                            isec->sclass,
4029                            UNIX_STREAM_SOCKET__CONNECTTO, &ad);
4030         if (err)
4031                 return err;
4032
4033         /* connecting socket */
4034         ssec = sock->sk->sk_security;
4035         ssec->peer_sid = other_isec->sid;
4036
4037         /* server child socket */
4038         ssec = newsk->sk_security;
4039         ssec->peer_sid = isec->sid;
4040         err = security_sid_mls_copy(other_isec->sid, ssec->peer_sid, &ssec->sid);
4041
4042         return err;
4043 }
4044
4045 static int selinux_socket_unix_may_send(struct socket *sock,
4046                                         struct socket *other)
4047 {
4048         struct inode_security_struct *isec;
4049         struct inode_security_struct *other_isec;
4050         struct avc_audit_data ad;
4051         int err;
4052
4053         isec = SOCK_INODE(sock)->i_security;
4054         other_isec = SOCK_INODE(other)->i_security;
4055
4056         AVC_AUDIT_DATA_INIT(&ad, NET);
4057         ad.u.net.sk = other->sk;
4058
4059         err = avc_has_perm(isec->sid, other_isec->sid,
4060                            isec->sclass, SOCKET__SENDTO, &ad);
4061         if (err)
4062                 return err;
4063
4064         return 0;
4065 }
4066
4067 static int selinux_inet_sys_rcv_skb(int ifindex, char *addrp, u16 family,
4068                                     u32 peer_sid,
4069                                     struct avc_audit_data *ad)
4070 {
4071         int err;
4072         u32 if_sid;
4073         u32 node_sid;
4074
4075         err = sel_netif_sid(ifindex, &if_sid);
4076         if (err)
4077                 return err;
4078         err = avc_has_perm(peer_sid, if_sid,
4079                            SECCLASS_NETIF, NETIF__INGRESS, ad);
4080         if (err)
4081                 return err;
4082
4083         err = sel_netnode_sid(addrp, family, &node_sid);
4084         if (err)
4085                 return err;
4086         return avc_has_perm(peer_sid, node_sid,
4087                             SECCLASS_NODE, NODE__RECVFROM, ad);
4088 }
4089
4090 static int selinux_sock_rcv_skb_iptables_compat(struct sock *sk,
4091                                                 struct sk_buff *skb,
4092                                                 struct avc_audit_data *ad,
4093                                                 u16 family,
4094                                                 char *addrp)
4095 {
4096         int err;
4097         struct sk_security_struct *sksec = sk->sk_security;
4098         u16 sk_class;
4099         u32 netif_perm, node_perm, recv_perm;
4100         u32 port_sid, node_sid, if_sid, sk_sid;
4101
4102         sk_sid = sksec->sid;
4103         sk_class = sksec->sclass;
4104
4105         switch (sk_class) {
4106         case SECCLASS_UDP_SOCKET:
4107                 netif_perm = NETIF__UDP_RECV;
4108                 node_perm = NODE__UDP_RECV;
4109                 recv_perm = UDP_SOCKET__RECV_MSG;
4110                 break;
4111         case SECCLASS_TCP_SOCKET:
4112                 netif_perm = NETIF__TCP_RECV;
4113                 node_perm = NODE__TCP_RECV;
4114                 recv_perm = TCP_SOCKET__RECV_MSG;
4115                 break;
4116         case SECCLASS_DCCP_SOCKET:
4117                 netif_perm = NETIF__DCCP_RECV;
4118                 node_perm = NODE__DCCP_RECV;
4119                 recv_perm = DCCP_SOCKET__RECV_MSG;
4120                 break;
4121         default:
4122                 netif_perm = NETIF__RAWIP_RECV;
4123                 node_perm = NODE__RAWIP_RECV;
4124                 recv_perm = 0;
4125                 break;
4126         }
4127
4128         err = sel_netif_sid(skb->iif, &if_sid);
4129         if (err)
4130                 return err;
4131         err = avc_has_perm(sk_sid, if_sid, SECCLASS_NETIF, netif_perm, ad);
4132         if (err)
4133                 return err;
4134
4135         err = sel_netnode_sid(addrp, family, &node_sid);
4136         if (err)
4137                 return err;
4138         err = avc_has_perm(sk_sid, node_sid, SECCLASS_NODE, node_perm, ad);
4139         if (err)
4140                 return err;
4141
4142         if (!recv_perm)
4143                 return 0;
4144         err = sel_netport_sid(sk->sk_protocol,
4145                               ntohs(ad->u.net.sport), &port_sid);
4146         if (unlikely(err)) {
4147                 printk(KERN_WARNING
4148                        "SELinux: failure in"
4149                        " selinux_sock_rcv_skb_iptables_compat(),"
4150                        " network port label not found\n");
4151                 return err;
4152         }
4153         return avc_has_perm(sk_sid, port_sid, sk_class, recv_perm, ad);
4154 }
4155
4156 static int selinux_sock_rcv_skb_compat(struct sock *sk, struct sk_buff *skb,
4157                                        u16 family)
4158 {
4159         int err = 0;
4160         struct sk_security_struct *sksec = sk->sk_security;
4161         u32 peer_sid;
4162         u32 sk_sid = sksec->sid;
4163         struct avc_audit_data ad;
4164         char *addrp;
4165
4166         AVC_AUDIT_DATA_INIT(&ad, NET);
4167         ad.u.net.netif = skb->iif;
4168         ad.u.net.family = family;
4169         err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL);
4170         if (err)
4171                 return err;
4172
4173         if (selinux_compat_net)
4174                 err = selinux_sock_rcv_skb_iptables_compat(sk, skb, &ad,
4175                                                            family, addrp);
4176         else if (selinux_secmark_enabled())
4177                 err = avc_has_perm(sk_sid, skb->secmark, SECCLASS_PACKET,
4178                                    PACKET__RECV, &ad);
4179         if (err)
4180                 return err;
4181
4182         if (selinux_policycap_netpeer) {
4183                 err = selinux_skb_peerlbl_sid(skb, family, &peer_sid);
4184                 if (err)
4185                         return err;
4186                 err = avc_has_perm(sk_sid, peer_sid,
4187                                    SECCLASS_PEER, PEER__RECV, &ad);
4188                 if (err)
4189                         selinux_netlbl_err(skb, err, 0);
4190         } else {
4191                 err = selinux_netlbl_sock_rcv_skb(sksec, skb, family, &ad);
4192                 if (err)
4193                         return err;
4194                 err = selinux_xfrm_sock_rcv_skb(sksec->sid, skb, &ad);
4195         }
4196
4197         return err;
4198 }
4199
4200 static int selinux_socket_sock_rcv_skb(struct sock *sk, struct sk_buff *skb)
4201 {
4202         int err;
4203         struct sk_security_struct *sksec = sk->sk_security;
4204         u16 family = sk->sk_family;
4205         u32 sk_sid = sksec->sid;
4206         struct avc_audit_data ad;
4207         char *addrp;
4208         u8 secmark_active;
4209         u8 peerlbl_active;
4210
4211         if (family != PF_INET && family != PF_INET6)
4212                 return 0;
4213
4214         /* Handle mapped IPv4 packets arriving via IPv6 sockets */
4215         if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
4216                 family = PF_INET;
4217
4218         /* If any sort of compatibility mode is enabled then handoff processing
4219          * to the selinux_sock_rcv_skb_compat() function to deal with the
4220          * special handling.  We do this in an attempt to keep this function
4221          * as fast and as clean as possible. */
4222         if (selinux_compat_net || !selinux_policycap_netpeer)
4223                 return selinux_sock_rcv_skb_compat(sk, skb, family);
4224
4225         secmark_active = selinux_secmark_enabled();
4226         peerlbl_active = netlbl_enabled() || selinux_xfrm_enabled();
4227         if (!secmark_active && !peerlbl_active)
4228                 return 0;
4229
4230         AVC_AUDIT_DATA_INIT(&ad, NET);
4231         ad.u.net.netif = skb->iif;
4232         ad.u.net.family = family;
4233         err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL);
4234         if (err)
4235                 return err;
4236
4237         if (peerlbl_active) {
4238                 u32 peer_sid;
4239
4240                 err = selinux_skb_peerlbl_sid(skb, family, &peer_sid);
4241                 if (err)
4242                         return err;
4243                 err = selinux_inet_sys_rcv_skb(skb->iif, addrp, family,
4244                                                peer_sid, &ad);
4245                 if (err) {
4246                         selinux_netlbl_err(skb, err, 0);
4247                         return err;
4248                 }
4249                 err = avc_has_perm(sk_sid, peer_sid, SECCLASS_PEER,
4250                                    PEER__RECV, &ad);
4251                 if (err)
4252                         selinux_netlbl_err(skb, err, 0);
4253         }
4254
4255         if (secmark_active) {
4256                 err = avc_has_perm(sk_sid, skb->secmark, SECCLASS_PACKET,
4257                                    PACKET__RECV, &ad);
4258                 if (err)
4259                         return err;
4260         }
4261
4262         return err;
4263 }
4264
4265 static int selinux_socket_getpeersec_stream(struct socket *sock, char __user *optval,
4266                                             int __user *optlen, unsigned len)
4267 {
4268         int err = 0;
4269         char *scontext;
4270         u32 scontext_len;
4271         struct sk_security_struct *ssec;
4272         struct inode_security_struct *isec;
4273         u32 peer_sid = SECSID_NULL;
4274
4275         isec = SOCK_INODE(sock)->i_security;
4276
4277         if (isec->sclass == SECCLASS_UNIX_STREAM_SOCKET ||
4278             isec->sclass == SECCLASS_TCP_SOCKET) {
4279                 ssec = sock->sk->sk_security;
4280                 peer_sid = ssec->peer_sid;
4281         }
4282         if (peer_sid == SECSID_NULL) {
4283                 err = -ENOPROTOOPT;
4284                 goto out;
4285         }
4286
4287         err = security_sid_to_context(peer_sid, &scontext, &scontext_len);
4288
4289         if (err)
4290                 goto out;
4291
4292         if (scontext_len > len) {
4293                 err = -ERANGE;
4294                 goto out_len;
4295         }
4296
4297         if (copy_to_user(optval, scontext, scontext_len))
4298                 err = -EFAULT;
4299
4300 out_len:
4301         if (put_user(scontext_len, optlen))
4302                 err = -EFAULT;
4303
4304         kfree(scontext);
4305 out:
4306         return err;
4307 }
4308
4309 static int selinux_socket_getpeersec_dgram(struct socket *sock, struct sk_buff *skb, u32 *secid)
4310 {
4311         u32 peer_secid = SECSID_NULL;
4312         u16 family;
4313
4314         if (skb && skb->protocol == htons(ETH_P_IP))
4315                 family = PF_INET;
4316         else if (skb && skb->protocol == htons(ETH_P_IPV6))
4317                 family = PF_INET6;
4318         else if (sock)
4319                 family = sock->sk->sk_family;
4320         else
4321                 goto out;
4322
4323         if (sock && family == PF_UNIX)
4324                 selinux_inode_getsecid(SOCK_INODE(sock), &peer_secid);
4325         else if (skb)
4326                 selinux_skb_peerlbl_sid(skb, family, &peer_secid);
4327
4328 out:
4329         *secid = peer_secid;
4330         if (peer_secid == SECSID_NULL)
4331                 return -EINVAL;
4332         return 0;
4333 }
4334
4335 static int selinux_sk_alloc_security(struct sock *sk, int family, gfp_t priority)
4336 {
4337         return sk_alloc_security(sk, family, priority);
4338 }
4339
4340 static void selinux_sk_free_security(struct sock *sk)
4341 {
4342         sk_free_security(sk);
4343 }
4344
4345 static void selinux_sk_clone_security(const struct sock *sk, struct sock *newsk)
4346 {
4347         struct sk_security_struct *ssec = sk->sk_security;
4348         struct sk_security_struct *newssec = newsk->sk_security;
4349
4350         newssec->sid = ssec->sid;
4351         newssec->peer_sid = ssec->peer_sid;
4352         newssec->sclass = ssec->sclass;
4353
4354         selinux_netlbl_sk_security_reset(newssec, newsk->sk_family);
4355 }
4356
4357 static void selinux_sk_getsecid(struct sock *sk, u32 *secid)
4358 {
4359         if (!sk)
4360                 *secid = SECINITSID_ANY_SOCKET;
4361         else {
4362                 struct sk_security_struct *sksec = sk->sk_security;
4363
4364                 *secid = sksec->sid;
4365         }
4366 }
4367
4368 static void selinux_sock_graft(struct sock *sk, struct socket *parent)
4369 {
4370         struct inode_security_struct *isec = SOCK_INODE(parent)->i_security;
4371         struct sk_security_struct *sksec = sk->sk_security;
4372
4373         if (sk->sk_family == PF_INET || sk->sk_family == PF_INET6 ||
4374             sk->sk_family == PF_UNIX)
4375                 isec->sid = sksec->sid;
4376         sksec->sclass = isec->sclass;
4377 }
4378
4379 static int selinux_inet_conn_request(struct sock *sk, struct sk_buff *skb,
4380                                      struct request_sock *req)
4381 {
4382         struct sk_security_struct *sksec = sk->sk_security;
4383         int err;
4384         u16 family = sk->sk_family;
4385         u32 newsid;
4386         u32 peersid;
4387
4388         /* handle mapped IPv4 packets arriving via IPv6 sockets */
4389         if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
4390                 family = PF_INET;
4391
4392         err = selinux_skb_peerlbl_sid(skb, family, &peersid);
4393         if (err)
4394                 return err;
4395         if (peersid == SECSID_NULL) {
4396                 req->secid = sksec->sid;
4397                 req->peer_secid = SECSID_NULL;
4398                 return 0;
4399         }
4400
4401         err = security_sid_mls_copy(sksec->sid, peersid, &newsid);
4402         if (err)
4403                 return err;
4404
4405         req->secid = newsid;
4406         req->peer_secid = peersid;
4407         return 0;
4408 }
4409
4410 static void selinux_inet_csk_clone(struct sock *newsk,
4411                                    const struct request_sock *req)
4412 {
4413         struct sk_security_struct *newsksec = newsk->sk_security;
4414
4415         newsksec->sid = req->secid;
4416         newsksec->peer_sid = req->peer_secid;
4417         /* NOTE: Ideally, we should also get the isec->sid for the
4418            new socket in sync, but we don't have the isec available yet.
4419            So we will wait until sock_graft to do it, by which
4420            time it will have been created and available. */
4421
4422         /* We don't need to take any sort of lock here as we are the only
4423          * thread with access to newsksec */
4424         selinux_netlbl_sk_security_reset(newsksec, req->rsk_ops->family);
4425 }
4426
4427 static void selinux_inet_conn_established(struct sock *sk, struct sk_buff *skb)
4428 {
4429         u16 family = sk->sk_family;
4430         struct sk_security_struct *sksec = sk->sk_security;
4431
4432         /* handle mapped IPv4 packets arriving via IPv6 sockets */
4433         if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
4434                 family = PF_INET;
4435
4436         selinux_skb_peerlbl_sid(skb, family, &sksec->peer_sid);
4437
4438         selinux_netlbl_inet_conn_established(sk, family);
4439 }
4440
4441 static void selinux_req_classify_flow(const struct request_sock *req,
4442                                       struct flowi *fl)
4443 {
4444         fl->secid = req->secid;
4445 }
4446
4447 static int selinux_nlmsg_perm(struct sock *sk, struct sk_buff *skb)
4448 {
4449         int err = 0;
4450         u32 perm;
4451         struct nlmsghdr *nlh;
4452         struct socket *sock = sk->sk_socket;
4453         struct inode_security_struct *isec = SOCK_INODE(sock)->i_security;
4454
4455         if (skb->len < NLMSG_SPACE(0)) {
4456                 err = -EINVAL;
4457                 goto out;
4458         }
4459         nlh = nlmsg_hdr(skb);
4460
4461         err = selinux_nlmsg_lookup(isec->sclass, nlh->nlmsg_type, &perm);
4462         if (err) {
4463                 if (err == -EINVAL) {
4464                         audit_log(current->audit_context, GFP_KERNEL, AUDIT_SELINUX_ERR,
4465                                   "SELinux:  unrecognized netlink message"
4466                                   " type=%hu for sclass=%hu\n",
4467                                   nlh->nlmsg_type, isec->sclass);
4468                         if (!selinux_enforcing || security_get_allow_unknown())
4469                                 err = 0;
4470                 }
4471
4472                 /* Ignore */
4473                 if (err == -ENOENT)
4474                         err = 0;
4475                 goto out;
4476         }
4477
4478         err = socket_has_perm(current, sock, perm);
4479 out:
4480         return err;
4481 }
4482
4483 #ifdef CONFIG_NETFILTER
4484
4485 static unsigned int selinux_ip_forward(struct sk_buff *skb, int ifindex,
4486                                        u16 family)
4487 {
4488         int err;
4489         char *addrp;
4490         u32 peer_sid;
4491         struct avc_audit_data ad;
4492         u8 secmark_active;
4493         u8 netlbl_active;
4494         u8 peerlbl_active;
4495
4496         if (!selinux_policycap_netpeer)
4497                 return NF_ACCEPT;
4498
4499         secmark_active = selinux_secmark_enabled();
4500         netlbl_active = netlbl_enabled();
4501         peerlbl_active = netlbl_active || selinux_xfrm_enabled();
4502         if (!secmark_active && !peerlbl_active)
4503                 return NF_ACCEPT;
4504
4505         if (selinux_skb_peerlbl_sid(skb, family, &peer_sid) != 0)
4506                 return NF_DROP;
4507
4508         AVC_AUDIT_DATA_INIT(&ad, NET);
4509         ad.u.net.netif = ifindex;
4510         ad.u.net.family = family;
4511         if (selinux_parse_skb(skb, &ad, &addrp, 1, NULL) != 0)
4512                 return NF_DROP;
4513
4514         if (peerlbl_active) {
4515                 err = selinux_inet_sys_rcv_skb(ifindex, addrp, family,
4516                                                peer_sid, &ad);
4517                 if (err) {
4518                         selinux_netlbl_err(skb, err, 1);
4519                         return NF_DROP;
4520                 }
4521         }
4522
4523         if (secmark_active)
4524                 if (avc_has_perm(peer_sid, skb->secmark,
4525                                  SECCLASS_PACKET, PACKET__FORWARD_IN, &ad))
4526                         return NF_DROP;
4527
4528         if (netlbl_active)
4529                 /* we do this in the FORWARD path and not the POST_ROUTING
4530                  * path because we want to make sure we apply the necessary
4531                  * labeling before IPsec is applied so we can leverage AH
4532                  * protection */
4533                 if (selinux_netlbl_skbuff_setsid(skb, family, peer_sid) != 0)
4534                         return NF_DROP;
4535
4536         return NF_ACCEPT;
4537 }
4538
4539 static unsigned int selinux_ipv4_forward(unsigned int hooknum,
4540                                          struct sk_buff *skb,
4541                                          const struct net_device *in,
4542                                          const struct net_device *out,
4543                                          int (*okfn)(struct sk_buff *))
4544 {
4545         return selinux_ip_forward(skb, in->ifindex, PF_INET);
4546 }
4547
4548 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
4549 static unsigned int selinux_ipv6_forward(unsigned int hooknum,
4550                                          struct sk_buff *skb,
4551                                          const struct net_device *in,
4552                                          const struct net_device *out,
4553                                          int (*okfn)(struct sk_buff *))
4554 {
4555         return selinux_ip_forward(skb, in->ifindex, PF_INET6);
4556 }
4557 #endif  /* IPV6 */
4558
4559 static unsigned int selinux_ip_output(struct sk_buff *skb,
4560                                       u16 family)
4561 {
4562         u32 sid;
4563
4564         if (!netlbl_enabled())
4565                 return NF_ACCEPT;
4566
4567         /* we do this in the LOCAL_OUT path and not the POST_ROUTING path
4568          * because we want to make sure we apply the necessary labeling
4569          * before IPsec is applied so we can leverage AH protection */
4570         if (skb->sk) {
4571                 struct sk_security_struct *sksec = skb->sk->sk_security;
4572                 sid = sksec->sid;
4573         } else
4574                 sid = SECINITSID_KERNEL;
4575         if (selinux_netlbl_skbuff_setsid(skb, family, sid) != 0)
4576                 return NF_DROP;
4577
4578         return NF_ACCEPT;
4579 }
4580
4581 static unsigned int selinux_ipv4_output(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_output(skb, PF_INET);
4588 }
4589
4590 static int selinux_ip_postroute_iptables_compat(struct sock *sk,
4591                                                 int ifindex,
4592                                                 struct avc_audit_data *ad,
4593                                                 u16 family, char *addrp)
4594 {
4595         int err;
4596         struct sk_security_struct *sksec = sk->sk_security;
4597         u16 sk_class;
4598         u32 netif_perm, node_perm, send_perm;
4599         u32 port_sid, node_sid, if_sid, sk_sid;
4600
4601         sk_sid = sksec->sid;
4602         sk_class = sksec->sclass;
4603
4604         switch (sk_class) {
4605         case SECCLASS_UDP_SOCKET:
4606                 netif_perm = NETIF__UDP_SEND;
4607                 node_perm = NODE__UDP_SEND;
4608                 send_perm = UDP_SOCKET__SEND_MSG;
4609                 break;
4610         case SECCLASS_TCP_SOCKET:
4611                 netif_perm = NETIF__TCP_SEND;
4612                 node_perm = NODE__TCP_SEND;
4613                 send_perm = TCP_SOCKET__SEND_MSG;
4614                 break;
4615         case SECCLASS_DCCP_SOCKET:
4616                 netif_perm = NETIF__DCCP_SEND;
4617                 node_perm = NODE__DCCP_SEND;
4618                 send_perm = DCCP_SOCKET__SEND_MSG;
4619                 break;
4620         default:
4621                 netif_perm = NETIF__RAWIP_SEND;
4622                 node_perm = NODE__RAWIP_SEND;
4623                 send_perm = 0;
4624                 break;
4625         }
4626
4627         err = sel_netif_sid(ifindex, &if_sid);
4628         if (err)
4629                 return err;
4630         err = avc_has_perm(sk_sid, if_sid, SECCLASS_NETIF, netif_perm, ad);
4631                 return err;
4632
4633         err = sel_netnode_sid(addrp, family, &node_sid);
4634         if (err)
4635                 return err;
4636         err = avc_has_perm(sk_sid, node_sid, SECCLASS_NODE, node_perm, ad);
4637         if (err)
4638                 return err;
4639
4640         if (send_perm != 0)
4641                 return 0;
4642
4643         err = sel_netport_sid(sk->sk_protocol,
4644                               ntohs(ad->u.net.dport), &port_sid);
4645         if (unlikely(err)) {
4646                 printk(KERN_WARNING
4647                        "SELinux: failure in"
4648                        " selinux_ip_postroute_iptables_compat(),"
4649                        " network port label not found\n");
4650                 return err;
4651         }
4652         return avc_has_perm(sk_sid, port_sid, sk_class, send_perm, ad);
4653 }
4654
4655 static unsigned int selinux_ip_postroute_compat(struct sk_buff *skb,
4656                                                 int ifindex,
4657                                                 u16 family)
4658 {
4659         struct sock *sk = skb->sk;
4660         struct sk_security_struct *sksec;
4661         struct avc_audit_data ad;
4662         char *addrp;
4663         u8 proto;
4664
4665         if (sk == NULL)
4666                 return NF_ACCEPT;
4667         sksec = sk->sk_security;
4668
4669         AVC_AUDIT_DATA_INIT(&ad, NET);
4670         ad.u.net.netif = ifindex;
4671         ad.u.net.family = family;
4672         if (selinux_parse_skb(skb, &ad, &addrp, 0, &proto))
4673                 return NF_DROP;
4674
4675         if (selinux_compat_net) {
4676                 if (selinux_ip_postroute_iptables_compat(skb->sk, ifindex,
4677                                                          &ad, family, addrp))
4678                         return NF_DROP;
4679         } else if (selinux_secmark_enabled()) {
4680                 if (avc_has_perm(sksec->sid, skb->secmark,
4681                                  SECCLASS_PACKET, PACKET__SEND, &ad))
4682                         return NF_DROP;
4683         }
4684
4685         if (selinux_policycap_netpeer)
4686                 if (selinux_xfrm_postroute_last(sksec->sid, skb, &ad, proto))
4687                         return NF_DROP;
4688
4689         return NF_ACCEPT;
4690 }
4691
4692 static unsigned int selinux_ip_postroute(struct sk_buff *skb, int ifindex,
4693                                          u16 family)
4694 {
4695         u32 secmark_perm;
4696         u32 peer_sid;
4697         struct sock *sk;
4698         struct avc_audit_data ad;
4699         char *addrp;
4700         u8 secmark_active;
4701         u8 peerlbl_active;
4702
4703         /* If any sort of compatibility mode is enabled then handoff processing
4704          * to the selinux_ip_postroute_compat() function to deal with the
4705          * special handling.  We do this in an attempt to keep this function
4706          * as fast and as clean as possible. */
4707         if (selinux_compat_net || !selinux_policycap_netpeer)
4708                 return selinux_ip_postroute_compat(skb, ifindex, family);
4709 #ifdef CONFIG_XFRM
4710         /* If skb->dst->xfrm is non-NULL then the packet is undergoing an IPsec
4711          * packet transformation so allow the packet to pass without any checks
4712          * since we'll have another chance to perform access control checks
4713          * when the packet is on it's final way out.
4714          * NOTE: there appear to be some IPv6 multicast cases where skb->dst
4715          *       is NULL, in this case go ahead and apply access control. */
4716         if (skb->dst != NULL && skb->dst->xfrm != NULL)
4717                 return NF_ACCEPT;
4718 #endif
4719         secmark_active = selinux_secmark_enabled();
4720         peerlbl_active = netlbl_enabled() || selinux_xfrm_enabled();
4721         if (!secmark_active && !peerlbl_active)
4722                 return NF_ACCEPT;
4723
4724         /* if the packet is being forwarded then get the peer label from the
4725          * packet itself; otherwise check to see if it is from a local
4726          * application or the kernel, if from an application get the peer label
4727          * from the sending socket, otherwise use the kernel's sid */
4728         sk = skb->sk;
4729         if (sk == NULL) {
4730                 switch (family) {
4731                 case PF_INET:
4732                         if (IPCB(skb)->flags & IPSKB_FORWARDED)
4733                                 secmark_perm = PACKET__FORWARD_OUT;
4734                         else
4735                                 secmark_perm = PACKET__SEND;
4736                         break;
4737                 case PF_INET6:
4738                         if (IP6CB(skb)->flags & IP6SKB_FORWARDED)
4739                                 secmark_perm = PACKET__FORWARD_OUT;
4740                         else
4741                                 secmark_perm = PACKET__SEND;
4742                         break;
4743                 default:
4744                         return NF_DROP;
4745                 }
4746                 if (secmark_perm == PACKET__FORWARD_OUT) {
4747                         if (selinux_skb_peerlbl_sid(skb, family, &peer_sid))
4748                                 return NF_DROP;
4749                 } else
4750                         peer_sid = SECINITSID_KERNEL;
4751         } else {
4752                 struct sk_security_struct *sksec = sk->sk_security;
4753                 peer_sid = sksec->sid;
4754                 secmark_perm = PACKET__SEND;
4755         }
4756
4757         AVC_AUDIT_DATA_INIT(&ad, NET);
4758         ad.u.net.netif = ifindex;
4759         ad.u.net.family = family;
4760         if (selinux_parse_skb(skb, &ad, &addrp, 0, NULL))
4761                 return NF_DROP;
4762
4763         if (secmark_active)
4764                 if (avc_has_perm(peer_sid, skb->secmark,
4765                                  SECCLASS_PACKET, secmark_perm, &ad))
4766                         return NF_DROP;
4767
4768         if (peerlbl_active) {
4769                 u32 if_sid;
4770                 u32 node_sid;
4771
4772                 if (sel_netif_sid(ifindex, &if_sid))
4773                         return NF_DROP;
4774                 if (avc_has_perm(peer_sid, if_sid,
4775                                  SECCLASS_NETIF, NETIF__EGRESS, &ad))
4776                         return NF_DROP;
4777
4778                 if (sel_netnode_sid(addrp, family, &node_sid))
4779                         return NF_DROP;
4780                 if (avc_has_perm(peer_sid, node_sid,
4781                                  SECCLASS_NODE, NODE__SENDTO, &ad))
4782                         return NF_DROP;
4783         }
4784
4785         return NF_ACCEPT;
4786 }
4787
4788 static unsigned int selinux_ipv4_postroute(unsigned int hooknum,
4789                                            struct sk_buff *skb,
4790                                            const struct net_device *in,
4791                                            const struct net_device *out,
4792                                            int (*okfn)(struct sk_buff *))
4793 {
4794         return selinux_ip_postroute(skb, out->ifindex, PF_INET);
4795 }
4796
4797 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
4798 static unsigned int selinux_ipv6_postroute(unsigned int hooknum,
4799                                            struct sk_buff *skb,
4800                                            const struct net_device *in,
4801                                            const struct net_device *out,
4802                                            int (*okfn)(struct sk_buff *))
4803 {
4804         return selinux_ip_postroute(skb, out->ifindex, PF_INET6);
4805 }
4806 #endif  /* IPV6 */
4807
4808 #endif  /* CONFIG_NETFILTER */
4809
4810 static int selinux_netlink_send(struct sock *sk, struct sk_buff *skb)
4811 {
4812         int err;
4813
4814         err = secondary_ops->netlink_send(sk, skb);
4815         if (err)
4816                 return err;
4817
4818         if (policydb_loaded_version >= POLICYDB_VERSION_NLCLASS)
4819                 err = selinux_nlmsg_perm(sk, skb);
4820
4821         return err;
4822 }
4823
4824 static int selinux_netlink_recv(struct sk_buff *skb, int capability)
4825 {
4826         int err;
4827         struct avc_audit_data ad;
4828
4829         err = secondary_ops->netlink_recv(skb, capability);
4830         if (err)
4831                 return err;
4832
4833         AVC_AUDIT_DATA_INIT(&ad, CAP);
4834         ad.u.cap = capability;
4835
4836         return avc_has_perm(NETLINK_CB(skb).sid, NETLINK_CB(skb).sid,
4837                             SECCLASS_CAPABILITY, CAP_TO_MASK(capability), &ad);
4838 }
4839
4840 static int ipc_alloc_security(struct task_struct *task,
4841                               struct kern_ipc_perm *perm,
4842                               u16 sclass)
4843 {
4844         struct ipc_security_struct *isec;
4845         u32 sid;
4846
4847         isec = kzalloc(sizeof(struct ipc_security_struct), GFP_KERNEL);
4848         if (!isec)
4849                 return -ENOMEM;
4850
4851         sid = task_sid(task);
4852         isec->sclass = sclass;
4853         isec->sid = sid;
4854         perm->security = isec;
4855
4856         return 0;
4857 }
4858
4859 static void ipc_free_security(struct kern_ipc_perm *perm)
4860 {
4861         struct ipc_security_struct *isec = perm->security;
4862         perm->security = NULL;
4863         kfree(isec);
4864 }
4865
4866 static int msg_msg_alloc_security(struct msg_msg *msg)
4867 {
4868         struct msg_security_struct *msec;
4869
4870         msec = kzalloc(sizeof(struct msg_security_struct), GFP_KERNEL);
4871         if (!msec)
4872                 return -ENOMEM;
4873
4874         msec->sid = SECINITSID_UNLABELED;
4875         msg->security = msec;
4876
4877         return 0;
4878 }
4879
4880 static void msg_msg_free_security(struct msg_msg *msg)
4881 {
4882         struct msg_security_struct *msec = msg->security;
4883
4884         msg->security = NULL;
4885         kfree(msec);
4886 }
4887
4888 static int ipc_has_perm(struct kern_ipc_perm *ipc_perms,
4889                         u32 perms)
4890 {
4891         struct ipc_security_struct *isec;
4892         struct avc_audit_data ad;
4893         u32 sid = current_sid();
4894
4895         isec = ipc_perms->security;
4896
4897         AVC_AUDIT_DATA_INIT(&ad, IPC);
4898         ad.u.ipc_id = ipc_perms->key;
4899
4900         return avc_has_perm(sid, isec->sid, isec->sclass, perms, &ad);
4901 }
4902
4903 static int selinux_msg_msg_alloc_security(struct msg_msg *msg)
4904 {
4905         return msg_msg_alloc_security(msg);
4906 }
4907
4908 static void selinux_msg_msg_free_security(struct msg_msg *msg)
4909 {
4910         msg_msg_free_security(msg);
4911 }
4912
4913 /* message queue security operations */
4914 static int selinux_msg_queue_alloc_security(struct msg_queue *msq)
4915 {
4916         struct ipc_security_struct *isec;
4917         struct avc_audit_data ad;
4918         u32 sid = current_sid();
4919         int rc;
4920
4921         rc = ipc_alloc_security(current, &msq->q_perm, SECCLASS_MSGQ);
4922         if (rc)
4923                 return rc;
4924
4925         isec = msq->q_perm.security;
4926
4927         AVC_AUDIT_DATA_INIT(&ad, IPC);
4928         ad.u.ipc_id = msq->q_perm.key;
4929
4930         rc = avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
4931                           MSGQ__CREATE, &ad);
4932         if (rc) {
4933                 ipc_free_security(&msq->q_perm);
4934                 return rc;
4935         }
4936         return 0;
4937 }
4938
4939 static void selinux_msg_queue_free_security(struct msg_queue *msq)
4940 {
4941         ipc_free_security(&msq->q_perm);
4942 }
4943
4944 static int selinux_msg_queue_associate(struct msg_queue *msq, int msqflg)
4945 {
4946         struct ipc_security_struct *isec;
4947         struct avc_audit_data ad;
4948         u32 sid = current_sid();
4949
4950         isec = msq->q_perm.security;
4951
4952         AVC_AUDIT_DATA_INIT(&ad, IPC);
4953         ad.u.ipc_id = msq->q_perm.key;
4954
4955         return avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
4956                             MSGQ__ASSOCIATE, &ad);
4957 }
4958
4959 static int selinux_msg_queue_msgctl(struct msg_queue *msq, int cmd)
4960 {
4961         int err;
4962         int perms;
4963
4964         switch (cmd) {
4965         case IPC_INFO:
4966         case MSG_INFO:
4967                 /* No specific object, just general system-wide information. */
4968                 return task_has_system(current, SYSTEM__IPC_INFO);
4969         case IPC_STAT:
4970         case MSG_STAT:
4971                 perms = MSGQ__GETATTR | MSGQ__ASSOCIATE;
4972                 break;
4973         case IPC_SET:
4974                 perms = MSGQ__SETATTR;
4975                 break;
4976         case IPC_RMID:
4977                 perms = MSGQ__DESTROY;
4978                 break;
4979         default:
4980                 return 0;
4981         }
4982
4983         err = ipc_has_perm(&msq->q_perm, perms);
4984         return err;
4985 }
4986
4987 static int selinux_msg_queue_msgsnd(struct msg_queue *msq, struct msg_msg *msg, int msqflg)
4988 {
4989         struct ipc_security_struct *isec;
4990         struct msg_security_struct *msec;
4991         struct avc_audit_data ad;
4992         u32 sid = current_sid();
4993         int rc;
4994
4995         isec = msq->q_perm.security;
4996         msec = msg->security;
4997
4998         /*
4999          * First time through, need to assign label to the message
5000          */
5001         if (msec->sid == SECINITSID_UNLABELED) {
5002                 /*
5003                  * Compute new sid based on current process and
5004                  * message queue this message will be stored in
5005                  */
5006                 rc = security_transition_sid(sid, isec->sid, SECCLASS_MSG,
5007                                              &msec->sid);
5008                 if (rc)
5009                         return rc;
5010         }
5011
5012         AVC_AUDIT_DATA_INIT(&ad, IPC);
5013         ad.u.ipc_id = msq->q_perm.key;
5014
5015         /* Can this process write to the queue? */
5016         rc = avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
5017                           MSGQ__WRITE, &ad);
5018         if (!rc)
5019                 /* Can this process send the message */
5020                 rc = avc_has_perm(sid, msec->sid, SECCLASS_MSG,
5021                                   MSG__SEND, &ad);
5022         if (!rc)
5023                 /* Can the message be put in the queue? */
5024                 rc = avc_has_perm(msec->sid, isec->sid, SECCLASS_MSGQ,
5025                                   MSGQ__ENQUEUE, &ad);
5026
5027         return rc;
5028 }
5029
5030 static int selinux_msg_queue_msgrcv(struct msg_queue *msq, struct msg_msg *msg,
5031                                     struct task_struct *target,
5032                                     long type, int mode)
5033 {
5034         struct ipc_security_struct *isec;
5035         struct msg_security_struct *msec;
5036         struct avc_audit_data ad;
5037         u32 sid = task_sid(target);
5038         int rc;
5039
5040         isec = msq->q_perm.security;
5041         msec = msg->security;
5042
5043         AVC_AUDIT_DATA_INIT(&ad, IPC);
5044         ad.u.ipc_id = msq->q_perm.key;
5045
5046         rc = avc_has_perm(sid, isec->sid,
5047                           SECCLASS_MSGQ, MSGQ__READ, &ad);
5048         if (!rc)
5049                 rc = avc_has_perm(sid, msec->sid,
5050                                   SECCLASS_MSG, MSG__RECEIVE, &ad);
5051         return rc;
5052 }
5053
5054 /* Shared Memory security operations */
5055 static int selinux_shm_alloc_security(struct shmid_kernel *shp)
5056 {
5057         struct ipc_security_struct *isec;
5058         struct avc_audit_data ad;
5059         u32 sid = current_sid();
5060         int rc;
5061
5062         rc = ipc_alloc_security(current, &shp->shm_perm, SECCLASS_SHM);
5063         if (rc)
5064                 return rc;
5065
5066         isec = shp->shm_perm.security;
5067
5068         AVC_AUDIT_DATA_INIT(&ad, IPC);
5069         ad.u.ipc_id = shp->shm_perm.key;
5070
5071         rc = avc_has_perm(sid, isec->sid, SECCLASS_SHM,
5072                           SHM__CREATE, &ad);
5073         if (rc) {
5074                 ipc_free_security(&shp->shm_perm);
5075                 return rc;
5076         }
5077         return 0;
5078 }
5079
5080 static void selinux_shm_free_security(struct shmid_kernel *shp)
5081 {
5082         ipc_free_security(&shp->shm_perm);
5083 }
5084
5085 static int selinux_shm_associate(struct shmid_kernel *shp, int shmflg)
5086 {
5087         struct ipc_security_struct *isec;
5088         struct avc_audit_data ad;
5089         u32 sid = current_sid();
5090
5091         isec = shp->shm_perm.security;
5092
5093         AVC_AUDIT_DATA_INIT(&ad, IPC);
5094         ad.u.ipc_id = shp->shm_perm.key;
5095
5096         return avc_has_perm(sid, isec->sid, SECCLASS_SHM,
5097                             SHM__ASSOCIATE, &ad);
5098 }
5099
5100 /* Note, at this point, shp is locked down */
5101 static int selinux_shm_shmctl(struct shmid_kernel *shp, int cmd)
5102 {
5103         int perms;
5104         int err;
5105
5106         switch (cmd) {
5107         case IPC_INFO:
5108         case SHM_INFO:
5109                 /* No specific object, just general system-wide information. */
5110                 return task_has_system(current, SYSTEM__IPC_INFO);
5111         case IPC_STAT:
5112         case SHM_STAT:
5113                 perms = SHM__GETATTR | SHM__ASSOCIATE;
5114                 break;
5115         case IPC_SET:
5116                 perms = SHM__SETATTR;
5117                 break;
5118         case SHM_LOCK:
5119         case SHM_UNLOCK:
5120                 perms = SHM__LOCK;
5121                 break;
5122         case IPC_RMID:
5123                 perms = SHM__DESTROY;
5124                 break;
5125         default:
5126                 return 0;
5127         }
5128
5129         err = ipc_has_perm(&shp->shm_perm, perms);
5130         return err;
5131 }
5132
5133 static int selinux_shm_shmat(struct shmid_kernel *shp,
5134                              char __user *shmaddr, int shmflg)
5135 {
5136         u32 perms;
5137         int rc;
5138
5139         rc = secondary_ops->shm_shmat(shp, shmaddr, shmflg);
5140         if (rc)
5141                 return rc;
5142
5143         if (shmflg & SHM_RDONLY)
5144                 perms = SHM__READ;
5145         else
5146                 perms = SHM__READ | SHM__WRITE;
5147
5148         return ipc_has_perm(&shp->shm_perm, perms);
5149 }
5150
5151 /* Semaphore security operations */
5152 static int selinux_sem_alloc_security(struct sem_array *sma)
5153 {
5154         struct ipc_security_struct *isec;
5155         struct avc_audit_data ad;
5156         u32 sid = current_sid();
5157         int rc;
5158
5159         rc = ipc_alloc_security(current, &sma->sem_perm, SECCLASS_SEM);
5160         if (rc)
5161                 return rc;
5162
5163         isec = sma->sem_perm.security;
5164
5165         AVC_AUDIT_DATA_INIT(&ad, IPC);
5166         ad.u.ipc_id = sma->sem_perm.key;
5167
5168         rc = avc_has_perm(sid, isec->sid, SECCLASS_SEM,
5169                           SEM__CREATE, &ad);
5170         if (rc) {
5171                 ipc_free_security(&sma->sem_perm);
5172                 return rc;
5173         }
5174         return 0;
5175 }
5176
5177 static void selinux_sem_free_security(struct sem_array *sma)
5178 {
5179         ipc_free_security(&sma->sem_perm);
5180 }
5181
5182 static int selinux_sem_associate(struct sem_array *sma, int semflg)
5183 {
5184         struct ipc_security_struct *isec;
5185         struct avc_audit_data ad;
5186         u32 sid = current_sid();
5187
5188         isec = sma->sem_perm.security;
5189
5190         AVC_AUDIT_DATA_INIT(&ad, IPC);
5191         ad.u.ipc_id = sma->sem_perm.key;
5192
5193         return avc_has_perm(sid, isec->sid, SECCLASS_SEM,
5194                             SEM__ASSOCIATE, &ad);
5195 }
5196
5197 /* Note, at this point, sma is locked down */
5198 static int selinux_sem_semctl(struct sem_array *sma, int cmd)
5199 {
5200         int err;
5201         u32 perms;
5202
5203         switch (cmd) {
5204         case IPC_INFO:
5205         case SEM_INFO:
5206                 /* No specific object, just general system-wide information. */
5207                 return task_has_system(current, SYSTEM__IPC_INFO);
5208         case GETPID:
5209         case GETNCNT:
5210         case GETZCNT:
5211                 perms = SEM__GETATTR;
5212                 break;
5213         case GETVAL:
5214         case GETALL:
5215                 perms = SEM__READ;
5216                 break;
5217         case SETVAL:
5218         case SETALL:
5219                 perms = SEM__WRITE;
5220                 break;
5221         case IPC_RMID:
5222                 perms = SEM__DESTROY;
5223                 break;
5224         case IPC_SET:
5225                 perms = SEM__SETATTR;
5226                 break;
5227         case IPC_STAT:
5228         case SEM_STAT:
5229                 perms = SEM__GETATTR | SEM__ASSOCIATE;
5230                 break;
5231         default:
5232                 return 0;
5233         }
5234
5235         err = ipc_has_perm(&sma->sem_perm, perms);
5236         return err;
5237 }
5238
5239 static int selinux_sem_semop(struct sem_array *sma,
5240                              struct sembuf *sops, unsigned nsops, int alter)
5241 {
5242         u32 perms;
5243
5244         if (alter)
5245                 perms = SEM__READ | SEM__WRITE;
5246         else
5247                 perms = SEM__READ;
5248
5249         return ipc_has_perm(&sma->sem_perm, perms);
5250 }
5251
5252 static int selinux_ipc_permission(struct kern_ipc_perm *ipcp, short flag)
5253 {
5254         u32 av = 0;
5255
5256         av = 0;
5257         if (flag & S_IRUGO)
5258                 av |= IPC__UNIX_READ;
5259         if (flag & S_IWUGO)
5260                 av |= IPC__UNIX_WRITE;
5261
5262         if (av == 0)
5263                 return 0;
5264
5265         return ipc_has_perm(ipcp, av);
5266 }
5267
5268 static void selinux_ipc_getsecid(struct kern_ipc_perm *ipcp, u32 *secid)
5269 {
5270         struct ipc_security_struct *isec = ipcp->security;
5271         *secid = isec->sid;
5272 }
5273
5274 static void selinux_d_instantiate(struct dentry *dentry, struct inode *inode)
5275 {
5276         if (inode)
5277                 inode_doinit_with_dentry(inode, dentry);
5278 }
5279
5280 static int selinux_getprocattr(struct task_struct *p,
5281                                char *name, char **value)
5282 {
5283         const struct task_security_struct *__tsec;
5284         u32 sid;
5285         int error;
5286         unsigned len;
5287
5288         if (current != p) {
5289                 error = current_has_perm(p, PROCESS__GETATTR);
5290                 if (error)
5291                         return error;
5292         }
5293
5294         rcu_read_lock();
5295         __tsec = __task_cred(p)->security;
5296
5297         if (!strcmp(name, "current"))
5298                 sid = __tsec->sid;
5299         else if (!strcmp(name, "prev"))
5300                 sid = __tsec->osid;
5301         else if (!strcmp(name, "exec"))
5302                 sid = __tsec->exec_sid;
5303         else if (!strcmp(name, "fscreate"))
5304                 sid = __tsec->create_sid;
5305         else if (!strcmp(name, "keycreate"))
5306                 sid = __tsec->keycreate_sid;
5307         else if (!strcmp(name, "sockcreate"))
5308                 sid = __tsec->sockcreate_sid;
5309         else
5310                 goto invalid;
5311         rcu_read_unlock();
5312
5313         if (!sid)
5314                 return 0;
5315
5316         error = security_sid_to_context(sid, value, &len);
5317         if (error)
5318                 return error;
5319         return len;
5320
5321 invalid:
5322         rcu_read_unlock();
5323         return -EINVAL;
5324 }
5325
5326 static int selinux_setprocattr(struct task_struct *p,
5327                                char *name, void *value, size_t size)
5328 {
5329         struct task_security_struct *tsec;
5330         struct task_struct *tracer;
5331         struct cred *new;
5332         u32 sid = 0, ptsid;
5333         int error;
5334         char *str = value;
5335
5336         if (current != p) {
5337                 /* SELinux only allows a process to change its own
5338                    security attributes. */
5339                 return -EACCES;
5340         }
5341
5342         /*
5343          * Basic control over ability to set these attributes at all.
5344          * current == p, but we'll pass them separately in case the
5345          * above restriction is ever removed.
5346          */
5347         if (!strcmp(name, "exec"))
5348                 error = current_has_perm(p, PROCESS__SETEXEC);
5349         else if (!strcmp(name, "fscreate"))
5350                 error = current_has_perm(p, PROCESS__SETFSCREATE);
5351         else if (!strcmp(name, "keycreate"))
5352                 error = current_has_perm(p, PROCESS__SETKEYCREATE);
5353         else if (!strcmp(name, "sockcreate"))
5354                 error = current_has_perm(p, PROCESS__SETSOCKCREATE);
5355         else if (!strcmp(name, "current"))
5356                 error = current_has_perm(p, PROCESS__SETCURRENT);
5357         else
5358                 error = -EINVAL;
5359         if (error)
5360                 return error;
5361
5362         /* Obtain a SID for the context, if one was specified. */
5363         if (size && str[1] && str[1] != '\n') {
5364                 if (str[size-1] == '\n') {
5365                         str[size-1] = 0;
5366                         size--;
5367                 }
5368                 error = security_context_to_sid(value, size, &sid);
5369                 if (error == -EINVAL && !strcmp(name, "fscreate")) {
5370                         if (!capable(CAP_MAC_ADMIN))
5371                                 return error;
5372                         error = security_context_to_sid_force(value, size,
5373                                                               &sid);
5374                 }
5375                 if (error)
5376                         return error;
5377         }
5378
5379         new = prepare_creds();
5380         if (!new)
5381                 return -ENOMEM;
5382
5383         /* Permission checking based on the specified context is
5384            performed during the actual operation (execve,
5385            open/mkdir/...), when we know the full context of the
5386            operation.  See selinux_bprm_set_creds for the execve
5387            checks and may_create for the file creation checks. The
5388            operation will then fail if the context is not permitted. */
5389         tsec = new->security;
5390         if (!strcmp(name, "exec")) {
5391                 tsec->exec_sid = sid;
5392         } else if (!strcmp(name, "fscreate")) {
5393                 tsec->create_sid = sid;
5394         } else if (!strcmp(name, "keycreate")) {
5395                 error = may_create_key(sid, p);
5396                 if (error)
5397                         goto abort_change;
5398                 tsec->keycreate_sid = sid;
5399         } else if (!strcmp(name, "sockcreate")) {
5400                 tsec->sockcreate_sid = sid;
5401         } else if (!strcmp(name, "current")) {
5402                 error = -EINVAL;
5403                 if (sid == 0)
5404                         goto abort_change;
5405
5406                 /* Only allow single threaded processes to change context */
5407                 error = -EPERM;
5408                 if (!is_single_threaded(p)) {
5409                         error = security_bounded_transition(tsec->sid, sid);
5410                         if (error)
5411                                 goto abort_change;
5412                 }
5413
5414                 /* Check permissions for the transition. */
5415                 error = avc_has_perm(tsec->sid, sid, SECCLASS_PROCESS,
5416                                      PROCESS__DYNTRANSITION, NULL);
5417                 if (error)
5418                         goto abort_change;
5419
5420                 /* Check for ptracing, and update the task SID if ok.
5421                    Otherwise, leave SID unchanged and fail. */
5422                 ptsid = 0;
5423                 task_lock(p);
5424                 tracer = tracehook_tracer_task(p);
5425                 if (tracer)
5426                         ptsid = task_sid(tracer);
5427                 task_unlock(p);
5428
5429                 if (tracer) {
5430                         error = avc_has_perm(ptsid, sid, SECCLASS_PROCESS,
5431                                              PROCESS__PTRACE, NULL);
5432                         if (error)
5433                                 goto abort_change;
5434                 }
5435
5436                 tsec->sid = sid;
5437         } else {
5438                 error = -EINVAL;
5439                 goto abort_change;
5440         }
5441
5442         commit_creds(new);
5443         return size;
5444
5445 abort_change:
5446         abort_creds(new);
5447         return error;
5448 }
5449
5450 static int selinux_secid_to_secctx(u32 secid, char **secdata, u32 *seclen)
5451 {
5452         return security_sid_to_context(secid, secdata, seclen);
5453 }
5454
5455 static int selinux_secctx_to_secid(const char *secdata, u32 seclen, u32 *secid)
5456 {
5457         return security_context_to_sid(secdata, seclen, secid);
5458 }
5459
5460 static void selinux_release_secctx(char *secdata, u32 seclen)
5461 {
5462         kfree(secdata);
5463 }
5464
5465 #ifdef CONFIG_KEYS
5466
5467 static int selinux_key_alloc(struct key *k, const struct cred *cred,
5468                              unsigned long flags)
5469 {
5470         const struct task_security_struct *tsec;
5471         struct key_security_struct *ksec;
5472
5473         ksec = kzalloc(sizeof(struct key_security_struct), GFP_KERNEL);
5474         if (!ksec)
5475                 return -ENOMEM;
5476
5477         tsec = cred->security;
5478         if (tsec->keycreate_sid)
5479                 ksec->sid = tsec->keycreate_sid;
5480         else
5481                 ksec->sid = tsec->sid;
5482
5483         k->security = ksec;
5484         return 0;
5485 }
5486
5487 static void selinux_key_free(struct key *k)
5488 {
5489         struct key_security_struct *ksec = k->security;
5490
5491         k->security = NULL;
5492         kfree(ksec);
5493 }
5494
5495 static int selinux_key_permission(key_ref_t key_ref,
5496                                   const struct cred *cred,
5497                                   key_perm_t perm)
5498 {
5499         struct key *key;
5500         struct key_security_struct *ksec;
5501         u32 sid;
5502
5503         /* if no specific permissions are requested, we skip the
5504            permission check. No serious, additional covert channels
5505            appear to be created. */
5506         if (perm == 0)
5507                 return 0;
5508
5509         sid = cred_sid(cred);
5510
5511         key = key_ref_to_ptr(key_ref);
5512         ksec = key->security;
5513
5514         return avc_has_perm(sid, ksec->sid, SECCLASS_KEY, perm, NULL);
5515 }
5516
5517 static int selinux_key_getsecurity(struct key *key, char **_buffer)
5518 {
5519         struct key_security_struct *ksec = key->security;
5520         char *context = NULL;
5521         unsigned len;
5522         int rc;
5523
5524         rc = security_sid_to_context(ksec->sid, &context, &len);
5525         if (!rc)
5526                 rc = len;
5527         *_buffer = context;
5528         return rc;
5529 }
5530
5531 #endif
5532
5533 static struct security_operations selinux_ops = {
5534         .name =                         "selinux",
5535
5536         .ptrace_may_access =            selinux_ptrace_may_access,
5537         .ptrace_traceme =               selinux_ptrace_traceme,
5538         .capget =                       selinux_capget,
5539         .capset =                       selinux_capset,
5540         .sysctl =                       selinux_sysctl,
5541         .capable =                      selinux_capable,
5542         .quotactl =                     selinux_quotactl,
5543         .quota_on =                     selinux_quota_on,
5544         .syslog =                       selinux_syslog,
5545         .vm_enough_memory =             selinux_vm_enough_memory,
5546
5547         .netlink_send =                 selinux_netlink_send,
5548         .netlink_recv =                 selinux_netlink_recv,
5549
5550         .bprm_set_creds =               selinux_bprm_set_creds,
5551         .bprm_committing_creds =        selinux_bprm_committing_creds,
5552         .bprm_committed_creds =         selinux_bprm_committed_creds,
5553         .bprm_secureexec =              selinux_bprm_secureexec,
5554
5555         .sb_alloc_security =            selinux_sb_alloc_security,
5556         .sb_free_security =             selinux_sb_free_security,
5557         .sb_copy_data =                 selinux_sb_copy_data,
5558         .sb_kern_mount =                selinux_sb_kern_mount,
5559         .sb_show_options =              selinux_sb_show_options,
5560         .sb_statfs =                    selinux_sb_statfs,
5561         .sb_mount =                     selinux_mount,
5562         .sb_umount =                    selinux_umount,
5563         .sb_set_mnt_opts =              selinux_set_mnt_opts,
5564         .sb_clone_mnt_opts =            selinux_sb_clone_mnt_opts,
5565         .sb_parse_opts_str =            selinux_parse_opts_str,
5566
5567
5568         .inode_alloc_security =         selinux_inode_alloc_security,
5569         .inode_free_security =          selinux_inode_free_security,
5570         .inode_init_security =          selinux_inode_init_security,
5571         .inode_create =                 selinux_inode_create,
5572         .inode_link =                   selinux_inode_link,
5573         .inode_unlink =                 selinux_inode_unlink,
5574         .inode_symlink =                selinux_inode_symlink,
5575         .inode_mkdir =                  selinux_inode_mkdir,
5576         .inode_rmdir =                  selinux_inode_rmdir,
5577         .inode_mknod =                  selinux_inode_mknod,
5578         .inode_rename =                 selinux_inode_rename,
5579         .inode_readlink =               selinux_inode_readlink,
5580         .inode_follow_link =            selinux_inode_follow_link,
5581         .inode_permission =             selinux_inode_permission,
5582         .inode_setattr =                selinux_inode_setattr,
5583         .inode_getattr =                selinux_inode_getattr,
5584         .inode_setxattr =               selinux_inode_setxattr,
5585         .inode_post_setxattr =          selinux_inode_post_setxattr,
5586         .inode_getxattr =               selinux_inode_getxattr,
5587         .inode_listxattr =              selinux_inode_listxattr,
5588         .inode_removexattr =            selinux_inode_removexattr,
5589         .inode_getsecurity =            selinux_inode_getsecurity,
5590         .inode_setsecurity =            selinux_inode_setsecurity,
5591         .inode_listsecurity =           selinux_inode_listsecurity,
5592         .inode_need_killpriv =          selinux_inode_need_killpriv,
5593         .inode_killpriv =               selinux_inode_killpriv,
5594         .inode_getsecid =               selinux_inode_getsecid,
5595
5596         .file_permission =              selinux_file_permission,
5597         .file_alloc_security =          selinux_file_alloc_security,
5598         .file_free_security =           selinux_file_free_security,
5599         .file_ioctl =                   selinux_file_ioctl,
5600         .file_mmap =                    selinux_file_mmap,
5601         .file_mprotect =                selinux_file_mprotect,
5602         .file_lock =                    selinux_file_lock,
5603         .file_fcntl =                   selinux_file_fcntl,
5604         .file_set_fowner =              selinux_file_set_fowner,
5605         .file_send_sigiotask =          selinux_file_send_sigiotask,
5606         .file_receive =                 selinux_file_receive,
5607
5608         .dentry_open =                  selinux_dentry_open,
5609
5610         .task_create =                  selinux_task_create,
5611         .cred_free =                    selinux_cred_free,
5612         .cred_prepare =                 selinux_cred_prepare,
5613         .cred_commit =                  selinux_cred_commit,
5614         .kernel_act_as =                selinux_kernel_act_as,
5615         .kernel_create_files_as =       selinux_kernel_create_files_as,
5616         .task_setuid =                  selinux_task_setuid,
5617         .task_fix_setuid =              selinux_task_fix_setuid,
5618         .task_setgid =                  selinux_task_setgid,
5619         .task_setpgid =                 selinux_task_setpgid,
5620         .task_getpgid =                 selinux_task_getpgid,
5621         .task_getsid =                  selinux_task_getsid,
5622         .task_getsecid =                selinux_task_getsecid,
5623         .task_setgroups =               selinux_task_setgroups,
5624         .task_setnice =                 selinux_task_setnice,
5625         .task_setioprio =               selinux_task_setioprio,
5626         .task_getioprio =               selinux_task_getioprio,
5627         .task_setrlimit =               selinux_task_setrlimit,
5628         .task_setscheduler =            selinux_task_setscheduler,
5629         .task_getscheduler =            selinux_task_getscheduler,
5630         .task_movememory =              selinux_task_movememory,
5631         .task_kill =                    selinux_task_kill,
5632         .task_wait =                    selinux_task_wait,
5633         .task_prctl =                   selinux_task_prctl,
5634         .task_to_inode =                selinux_task_to_inode,
5635
5636         .ipc_permission =               selinux_ipc_permission,
5637         .ipc_getsecid =                 selinux_ipc_getsecid,
5638
5639         .msg_msg_alloc_security =       selinux_msg_msg_alloc_security,
5640         .msg_msg_free_security =        selinux_msg_msg_free_security,
5641
5642         .msg_queue_alloc_security =     selinux_msg_queue_alloc_security,
5643         .msg_queue_free_security =      selinux_msg_queue_free_security,
5644         .msg_queue_associate =          selinux_msg_queue_associate,
5645         .msg_queue_msgctl =             selinux_msg_queue_msgctl,
5646         .msg_queue_msgsnd =             selinux_msg_queue_msgsnd,
5647         .msg_queue_msgrcv =             selinux_msg_queue_msgrcv,
5648
5649         .shm_alloc_security =           selinux_shm_alloc_security,
5650         .shm_free_security =            selinux_shm_free_security,
5651         .shm_associate =                selinux_shm_associate,
5652         .shm_shmctl =                   selinux_shm_shmctl,
5653         .shm_shmat =                    selinux_shm_shmat,
5654
5655         .sem_alloc_security =           selinux_sem_alloc_security,
5656         .sem_free_security =            selinux_sem_free_security,
5657         .sem_associate =                selinux_sem_associate,
5658         .sem_semctl =                   selinux_sem_semctl,
5659         .sem_semop =                    selinux_sem_semop,
5660
5661         .d_instantiate =                selinux_d_instantiate,
5662
5663         .getprocattr =                  selinux_getprocattr,
5664         .setprocattr =                  selinux_setprocattr,
5665
5666         .secid_to_secctx =              selinux_secid_to_secctx,
5667         .secctx_to_secid =              selinux_secctx_to_secid,
5668         .release_secctx =               selinux_release_secctx,
5669
5670         .unix_stream_connect =          selinux_socket_unix_stream_connect,
5671         .unix_may_send =                selinux_socket_unix_may_send,
5672
5673         .socket_create =                selinux_socket_create,
5674         .socket_post_create =           selinux_socket_post_create,
5675         .socket_bind =                  selinux_socket_bind,
5676         .socket_connect =               selinux_socket_connect,
5677         .socket_listen =                selinux_socket_listen,
5678         .socket_accept =                selinux_socket_accept,
5679         .socket_sendmsg =               selinux_socket_sendmsg,
5680         .socket_recvmsg =               selinux_socket_recvmsg,
5681         .socket_getsockname =           selinux_socket_getsockname,
5682         .socket_getpeername =           selinux_socket_getpeername,
5683         .socket_getsockopt =            selinux_socket_getsockopt,
5684         .socket_setsockopt =            selinux_socket_setsockopt,
5685         .socket_shutdown =              selinux_socket_shutdown,
5686         .socket_sock_rcv_skb =          selinux_socket_sock_rcv_skb,
5687         .socket_getpeersec_stream =     selinux_socket_getpeersec_stream,
5688         .socket_getpeersec_dgram =      selinux_socket_getpeersec_dgram,
5689         .sk_alloc_security =            selinux_sk_alloc_security,
5690         .sk_free_security =             selinux_sk_free_security,
5691         .sk_clone_security =            selinux_sk_clone_security,
5692         .sk_getsecid =                  selinux_sk_getsecid,
5693         .sock_graft =                   selinux_sock_graft,
5694         .inet_conn_request =            selinux_inet_conn_request,
5695         .inet_csk_clone =               selinux_inet_csk_clone,
5696         .inet_conn_established =        selinux_inet_conn_established,
5697         .req_classify_flow =            selinux_req_classify_flow,
5698
5699 #ifdef CONFIG_SECURITY_NETWORK_XFRM
5700         .xfrm_policy_alloc_security =   selinux_xfrm_policy_alloc,
5701         .xfrm_policy_clone_security =   selinux_xfrm_policy_clone,
5702         .xfrm_policy_free_security =    selinux_xfrm_policy_free,
5703         .xfrm_policy_delete_security =  selinux_xfrm_policy_delete,
5704         .xfrm_state_alloc_security =    selinux_xfrm_state_alloc,
5705         .xfrm_state_free_security =     selinux_xfrm_state_free,
5706         .xfrm_state_delete_security =   selinux_xfrm_state_delete,
5707         .xfrm_policy_lookup =           selinux_xfrm_policy_lookup,
5708         .xfrm_state_pol_flow_match =    selinux_xfrm_state_pol_flow_match,
5709         .xfrm_decode_session =          selinux_xfrm_decode_session,
5710 #endif
5711
5712 #ifdef CONFIG_KEYS
5713         .key_alloc =                    selinux_key_alloc,
5714         .key_free =                     selinux_key_free,
5715         .key_permission =               selinux_key_permission,
5716         .key_getsecurity =              selinux_key_getsecurity,
5717 #endif
5718
5719 #ifdef CONFIG_AUDIT
5720         .audit_rule_init =              selinux_audit_rule_init,
5721         .audit_rule_known =             selinux_audit_rule_known,
5722         .audit_rule_match =             selinux_audit_rule_match,
5723         .audit_rule_free =              selinux_audit_rule_free,
5724 #endif
5725 };
5726
5727 static __init int selinux_init(void)
5728 {
5729         if (!security_module_enable(&selinux_ops)) {
5730                 selinux_enabled = 0;
5731                 return 0;
5732         }
5733
5734         if (!selinux_enabled) {
5735                 printk(KERN_INFO "SELinux:  Disabled at boot.\n");
5736                 return 0;
5737         }
5738
5739         printk(KERN_INFO "SELinux:  Initializing.\n");
5740
5741         /* Set the security state for the initial task. */
5742         cred_init_security();
5743
5744         sel_inode_cache = kmem_cache_create("selinux_inode_security",
5745                                             sizeof(struct inode_security_struct),
5746                                             0, SLAB_PANIC, NULL);
5747         avc_init();
5748
5749         secondary_ops = security_ops;
5750         if (!secondary_ops)
5751                 panic("SELinux: No initial security operations\n");
5752         if (register_security(&selinux_ops))
5753                 panic("SELinux: Unable to register with kernel.\n");
5754
5755         if (selinux_enforcing)
5756                 printk(KERN_DEBUG "SELinux:  Starting in enforcing mode\n");
5757         else
5758                 printk(KERN_DEBUG "SELinux:  Starting in permissive mode\n");
5759
5760         return 0;
5761 }
5762
5763 void selinux_complete_init(void)
5764 {
5765         printk(KERN_DEBUG "SELinux:  Completing initialization.\n");
5766
5767         /* Set up any superblocks initialized prior to the policy load. */
5768         printk(KERN_DEBUG "SELinux:  Setting up existing superblocks.\n");
5769         spin_lock(&sb_lock);
5770         spin_lock(&sb_security_lock);
5771 next_sb:
5772         if (!list_empty(&superblock_security_head)) {
5773                 struct superblock_security_struct *sbsec =
5774                                 list_entry(superblock_security_head.next,
5775                                            struct superblock_security_struct,
5776                                            list);
5777                 struct super_block *sb = sbsec->sb;
5778                 sb->s_count++;
5779                 spin_unlock(&sb_security_lock);
5780                 spin_unlock(&sb_lock);
5781                 down_read(&sb->s_umount);
5782                 if (sb->s_root)
5783                         superblock_doinit(sb, NULL);
5784                 drop_super(sb);
5785                 spin_lock(&sb_lock);
5786                 spin_lock(&sb_security_lock);
5787                 list_del_init(&sbsec->list);
5788                 goto next_sb;
5789         }
5790         spin_unlock(&sb_security_lock);
5791         spin_unlock(&sb_lock);
5792 }
5793
5794 /* SELinux requires early initialization in order to label
5795    all processes and objects when they are created. */
5796 security_initcall(selinux_init);
5797
5798 #if defined(CONFIG_NETFILTER)
5799
5800 static struct nf_hook_ops selinux_ipv4_ops[] = {
5801         {
5802                 .hook =         selinux_ipv4_postroute,
5803                 .owner =        THIS_MODULE,
5804                 .pf =           PF_INET,
5805                 .hooknum =      NF_INET_POST_ROUTING,
5806                 .priority =     NF_IP_PRI_SELINUX_LAST,
5807         },
5808         {
5809                 .hook =         selinux_ipv4_forward,
5810                 .owner =        THIS_MODULE,
5811                 .pf =           PF_INET,
5812                 .hooknum =      NF_INET_FORWARD,
5813                 .priority =     NF_IP_PRI_SELINUX_FIRST,
5814         },
5815         {
5816                 .hook =         selinux_ipv4_output,
5817                 .owner =        THIS_MODULE,
5818                 .pf =           PF_INET,
5819                 .hooknum =      NF_INET_LOCAL_OUT,
5820                 .priority =     NF_IP_PRI_SELINUX_FIRST,
5821         }
5822 };
5823
5824 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
5825
5826 static struct nf_hook_ops selinux_ipv6_ops[] = {
5827         {
5828                 .hook =         selinux_ipv6_postroute,
5829                 .owner =        THIS_MODULE,
5830                 .pf =           PF_INET6,
5831                 .hooknum =      NF_INET_POST_ROUTING,
5832                 .priority =     NF_IP6_PRI_SELINUX_LAST,
5833         },
5834         {
5835                 .hook =         selinux_ipv6_forward,
5836                 .owner =        THIS_MODULE,
5837                 .pf =           PF_INET6,
5838                 .hooknum =      NF_INET_FORWARD,
5839                 .priority =     NF_IP6_PRI_SELINUX_FIRST,
5840         }
5841 };
5842
5843 #endif  /* IPV6 */
5844
5845 static int __init selinux_nf_ip_init(void)
5846 {
5847         int err = 0;
5848
5849         if (!selinux_enabled)
5850                 goto out;
5851
5852         printk(KERN_DEBUG "SELinux:  Registering netfilter hooks\n");
5853
5854         err = nf_register_hooks(selinux_ipv4_ops, ARRAY_SIZE(selinux_ipv4_ops));
5855         if (err)
5856                 panic("SELinux: nf_register_hooks for IPv4: error %d\n", err);
5857
5858 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
5859         err = nf_register_hooks(selinux_ipv6_ops, ARRAY_SIZE(selinux_ipv6_ops));
5860         if (err)
5861                 panic("SELinux: nf_register_hooks for IPv6: error %d\n", err);
5862 #endif  /* IPV6 */
5863
5864 out:
5865         return err;
5866 }
5867
5868 __initcall(selinux_nf_ip_init);
5869
5870 #ifdef CONFIG_SECURITY_SELINUX_DISABLE
5871 static void selinux_nf_ip_exit(void)
5872 {
5873         printk(KERN_DEBUG "SELinux:  Unregistering netfilter hooks\n");
5874
5875         nf_unregister_hooks(selinux_ipv4_ops, ARRAY_SIZE(selinux_ipv4_ops));
5876 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
5877         nf_unregister_hooks(selinux_ipv6_ops, ARRAY_SIZE(selinux_ipv6_ops));
5878 #endif  /* IPV6 */
5879 }
5880 #endif
5881
5882 #else /* CONFIG_NETFILTER */
5883
5884 #ifdef CONFIG_SECURITY_SELINUX_DISABLE
5885 #define selinux_nf_ip_exit()
5886 #endif
5887
5888 #endif /* CONFIG_NETFILTER */
5889
5890 #ifdef CONFIG_SECURITY_SELINUX_DISABLE
5891 static int selinux_disabled;
5892
5893 int selinux_disable(void)
5894 {
5895         extern void exit_sel_fs(void);
5896
5897         if (ss_initialized) {
5898                 /* Not permitted after initial policy load. */
5899                 return -EINVAL;
5900         }
5901
5902         if (selinux_disabled) {
5903                 /* Only do this once. */
5904                 return -EINVAL;
5905         }
5906
5907         printk(KERN_INFO "SELinux:  Disabled at runtime.\n");
5908
5909         selinux_disabled = 1;
5910         selinux_enabled = 0;
5911
5912         /* Reset security_ops to the secondary module, dummy or capability. */
5913         security_ops = secondary_ops;
5914
5915         /* Unregister netfilter hooks. */
5916         selinux_nf_ip_exit();
5917
5918         /* Unregister selinuxfs. */
5919         exit_sel_fs();
5920
5921         return 0;
5922 }
5923 #endif