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  * set the security data for a kernel service
3249  * - all the creation contexts are set to unlabelled
3250  */
3251 static int selinux_kernel_act_as(struct cred *new, u32 secid)
3252 {
3253         struct task_security_struct *tsec = new->security;
3254         u32 sid = current_sid();
3255         int ret;
3256
3257         ret = avc_has_perm(sid, secid,
3258                            SECCLASS_KERNEL_SERVICE,
3259                            KERNEL_SERVICE__USE_AS_OVERRIDE,
3260                            NULL);
3261         if (ret == 0) {
3262                 tsec->sid = secid;
3263                 tsec->create_sid = 0;
3264                 tsec->keycreate_sid = 0;
3265                 tsec->sockcreate_sid = 0;
3266         }
3267         return ret;
3268 }
3269
3270 /*
3271  * set the file creation context in a security record to the same as the
3272  * objective context of the specified inode
3273  */
3274 static int selinux_kernel_create_files_as(struct cred *new, struct inode *inode)
3275 {
3276         struct inode_security_struct *isec = inode->i_security;
3277         struct task_security_struct *tsec = new->security;
3278         u32 sid = current_sid();
3279         int ret;
3280
3281         ret = avc_has_perm(sid, isec->sid,
3282                            SECCLASS_KERNEL_SERVICE,
3283                            KERNEL_SERVICE__CREATE_FILES_AS,
3284                            NULL);
3285
3286         if (ret == 0)
3287                 tsec->create_sid = isec->sid;
3288         return 0;
3289 }
3290
3291 static int selinux_task_setuid(uid_t id0, uid_t id1, uid_t id2, int flags)
3292 {
3293         /* Since setuid only affects the current process, and
3294            since the SELinux controls are not based on the Linux
3295            identity attributes, SELinux does not need to control
3296            this operation.  However, SELinux does control the use
3297            of the CAP_SETUID and CAP_SETGID capabilities using the
3298            capable hook. */
3299         return 0;
3300 }
3301
3302 static int selinux_task_fix_setuid(struct cred *new, const struct cred *old,
3303                                    int flags)
3304 {
3305         return secondary_ops->task_fix_setuid(new, old, flags);
3306 }
3307
3308 static int selinux_task_setgid(gid_t id0, gid_t id1, gid_t id2, int flags)
3309 {
3310         /* See the comment for setuid above. */
3311         return 0;
3312 }
3313
3314 static int selinux_task_setpgid(struct task_struct *p, pid_t pgid)
3315 {
3316         return current_has_perm(p, PROCESS__SETPGID);
3317 }
3318
3319 static int selinux_task_getpgid(struct task_struct *p)
3320 {
3321         return current_has_perm(p, PROCESS__GETPGID);
3322 }
3323
3324 static int selinux_task_getsid(struct task_struct *p)
3325 {
3326         return current_has_perm(p, PROCESS__GETSESSION);
3327 }
3328
3329 static void selinux_task_getsecid(struct task_struct *p, u32 *secid)
3330 {
3331         *secid = task_sid(p);
3332 }
3333
3334 static int selinux_task_setgroups(struct group_info *group_info)
3335 {
3336         /* See the comment for setuid above. */
3337         return 0;
3338 }
3339
3340 static int selinux_task_setnice(struct task_struct *p, int nice)
3341 {
3342         int rc;
3343
3344         rc = secondary_ops->task_setnice(p, nice);
3345         if (rc)
3346                 return rc;
3347
3348         return current_has_perm(p, PROCESS__SETSCHED);
3349 }
3350
3351 static int selinux_task_setioprio(struct task_struct *p, int ioprio)
3352 {
3353         int rc;
3354
3355         rc = secondary_ops->task_setioprio(p, ioprio);
3356         if (rc)
3357                 return rc;
3358
3359         return current_has_perm(p, PROCESS__SETSCHED);
3360 }
3361
3362 static int selinux_task_getioprio(struct task_struct *p)
3363 {
3364         return current_has_perm(p, PROCESS__GETSCHED);
3365 }
3366
3367 static int selinux_task_setrlimit(unsigned int resource, struct rlimit *new_rlim)
3368 {
3369         struct rlimit *old_rlim = current->signal->rlim + resource;
3370         int rc;
3371
3372         rc = secondary_ops->task_setrlimit(resource, new_rlim);
3373         if (rc)
3374                 return rc;
3375
3376         /* Control the ability to change the hard limit (whether
3377            lowering or raising it), so that the hard limit can
3378            later be used as a safe reset point for the soft limit
3379            upon context transitions.  See selinux_bprm_committing_creds. */
3380         if (old_rlim->rlim_max != new_rlim->rlim_max)
3381                 return current_has_perm(current, PROCESS__SETRLIMIT);
3382
3383         return 0;
3384 }
3385
3386 static int selinux_task_setscheduler(struct task_struct *p, int policy, struct sched_param *lp)
3387 {
3388         int rc;
3389
3390         rc = secondary_ops->task_setscheduler(p, policy, lp);
3391         if (rc)
3392                 return rc;
3393
3394         return current_has_perm(p, PROCESS__SETSCHED);
3395 }
3396
3397 static int selinux_task_getscheduler(struct task_struct *p)
3398 {
3399         return current_has_perm(p, PROCESS__GETSCHED);
3400 }
3401
3402 static int selinux_task_movememory(struct task_struct *p)
3403 {
3404         return current_has_perm(p, PROCESS__SETSCHED);
3405 }
3406
3407 static int selinux_task_kill(struct task_struct *p, struct siginfo *info,
3408                                 int sig, u32 secid)
3409 {
3410         u32 perm;
3411         int rc;
3412
3413         rc = secondary_ops->task_kill(p, info, sig, secid);
3414         if (rc)
3415                 return rc;
3416
3417         if (!sig)
3418                 perm = PROCESS__SIGNULL; /* null signal; existence test */
3419         else
3420                 perm = signal_to_av(sig);
3421         if (secid)
3422                 rc = avc_has_perm(secid, task_sid(p),
3423                                   SECCLASS_PROCESS, perm, NULL);
3424         else
3425                 rc = current_has_perm(p, perm);
3426         return rc;
3427 }
3428
3429 static int selinux_task_prctl(int option,
3430                               unsigned long arg2,
3431                               unsigned long arg3,
3432                               unsigned long arg4,
3433                               unsigned long arg5)
3434 {
3435         /* The current prctl operations do not appear to require
3436            any SELinux controls since they merely observe or modify
3437            the state of the current process. */
3438         return secondary_ops->task_prctl(option, arg2, arg3, arg4, arg5);
3439 }
3440
3441 static int selinux_task_wait(struct task_struct *p)
3442 {
3443         return task_has_perm(p, current, PROCESS__SIGCHLD);
3444 }
3445
3446 static void selinux_task_to_inode(struct task_struct *p,
3447                                   struct inode *inode)
3448 {
3449         struct inode_security_struct *isec = inode->i_security;
3450         u32 sid = task_sid(p);
3451
3452         isec->sid = sid;
3453         isec->initialized = 1;
3454 }
3455
3456 /* Returns error only if unable to parse addresses */
3457 static int selinux_parse_skb_ipv4(struct sk_buff *skb,
3458                         struct avc_audit_data *ad, u8 *proto)
3459 {
3460         int offset, ihlen, ret = -EINVAL;
3461         struct iphdr _iph, *ih;
3462
3463         offset = skb_network_offset(skb);
3464         ih = skb_header_pointer(skb, offset, sizeof(_iph), &_iph);
3465         if (ih == NULL)
3466                 goto out;
3467
3468         ihlen = ih->ihl * 4;
3469         if (ihlen < sizeof(_iph))
3470                 goto out;
3471
3472         ad->u.net.v4info.saddr = ih->saddr;
3473         ad->u.net.v4info.daddr = ih->daddr;
3474         ret = 0;
3475
3476         if (proto)
3477                 *proto = ih->protocol;
3478
3479         switch (ih->protocol) {
3480         case IPPROTO_TCP: {
3481                 struct tcphdr _tcph, *th;
3482
3483                 if (ntohs(ih->frag_off) & IP_OFFSET)
3484                         break;
3485
3486                 offset += ihlen;
3487                 th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph);
3488                 if (th == NULL)
3489                         break;
3490
3491                 ad->u.net.sport = th->source;
3492                 ad->u.net.dport = th->dest;
3493                 break;
3494         }
3495
3496         case IPPROTO_UDP: {
3497                 struct udphdr _udph, *uh;
3498
3499                 if (ntohs(ih->frag_off) & IP_OFFSET)
3500                         break;
3501
3502                 offset += ihlen;
3503                 uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph);
3504                 if (uh == NULL)
3505                         break;
3506
3507                 ad->u.net.sport = uh->source;
3508                 ad->u.net.dport = uh->dest;
3509                 break;
3510         }
3511
3512         case IPPROTO_DCCP: {
3513                 struct dccp_hdr _dccph, *dh;
3514
3515                 if (ntohs(ih->frag_off) & IP_OFFSET)
3516                         break;
3517
3518                 offset += ihlen;
3519                 dh = skb_header_pointer(skb, offset, sizeof(_dccph), &_dccph);
3520                 if (dh == NULL)
3521                         break;
3522
3523                 ad->u.net.sport = dh->dccph_sport;
3524                 ad->u.net.dport = dh->dccph_dport;
3525                 break;
3526         }
3527
3528         default:
3529                 break;
3530         }
3531 out:
3532         return ret;
3533 }
3534
3535 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
3536
3537 /* Returns error only if unable to parse addresses */
3538 static int selinux_parse_skb_ipv6(struct sk_buff *skb,
3539                         struct avc_audit_data *ad, u8 *proto)
3540 {
3541         u8 nexthdr;
3542         int ret = -EINVAL, offset;
3543         struct ipv6hdr _ipv6h, *ip6;
3544
3545         offset = skb_network_offset(skb);
3546         ip6 = skb_header_pointer(skb, offset, sizeof(_ipv6h), &_ipv6h);
3547         if (ip6 == NULL)
3548                 goto out;
3549
3550         ipv6_addr_copy(&ad->u.net.v6info.saddr, &ip6->saddr);
3551         ipv6_addr_copy(&ad->u.net.v6info.daddr, &ip6->daddr);
3552         ret = 0;
3553
3554         nexthdr = ip6->nexthdr;
3555         offset += sizeof(_ipv6h);
3556         offset = ipv6_skip_exthdr(skb, offset, &nexthdr);
3557         if (offset < 0)
3558                 goto out;
3559
3560         if (proto)
3561                 *proto = nexthdr;
3562
3563         switch (nexthdr) {
3564         case IPPROTO_TCP: {
3565                 struct tcphdr _tcph, *th;
3566
3567                 th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph);
3568                 if (th == NULL)
3569                         break;
3570
3571                 ad->u.net.sport = th->source;
3572                 ad->u.net.dport = th->dest;
3573                 break;
3574         }
3575
3576         case IPPROTO_UDP: {
3577                 struct udphdr _udph, *uh;
3578
3579                 uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph);
3580                 if (uh == NULL)
3581                         break;
3582
3583                 ad->u.net.sport = uh->source;
3584                 ad->u.net.dport = uh->dest;
3585                 break;
3586         }
3587
3588         case IPPROTO_DCCP: {
3589                 struct dccp_hdr _dccph, *dh;
3590
3591                 dh = skb_header_pointer(skb, offset, sizeof(_dccph), &_dccph);
3592                 if (dh == NULL)
3593                         break;
3594
3595                 ad->u.net.sport = dh->dccph_sport;
3596                 ad->u.net.dport = dh->dccph_dport;
3597                 break;
3598         }
3599
3600         /* includes fragments */
3601         default:
3602                 break;
3603         }
3604 out:
3605         return ret;
3606 }
3607
3608 #endif /* IPV6 */
3609
3610 static int selinux_parse_skb(struct sk_buff *skb, struct avc_audit_data *ad,
3611                              char **_addrp, int src, u8 *proto)
3612 {
3613         char *addrp;
3614         int ret;
3615
3616         switch (ad->u.net.family) {
3617         case PF_INET:
3618                 ret = selinux_parse_skb_ipv4(skb, ad, proto);
3619                 if (ret)
3620                         goto parse_error;
3621                 addrp = (char *)(src ? &ad->u.net.v4info.saddr :
3622                                        &ad->u.net.v4info.daddr);
3623                 goto okay;
3624
3625 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
3626         case PF_INET6:
3627                 ret = selinux_parse_skb_ipv6(skb, ad, proto);
3628                 if (ret)
3629                         goto parse_error;
3630                 addrp = (char *)(src ? &ad->u.net.v6info.saddr :
3631                                        &ad->u.net.v6info.daddr);
3632                 goto okay;
3633 #endif  /* IPV6 */
3634         default:
3635                 addrp = NULL;
3636                 goto okay;
3637         }
3638
3639 parse_error:
3640         printk(KERN_WARNING
3641                "SELinux: failure in selinux_parse_skb(),"
3642                " unable to parse packet\n");
3643         return ret;
3644
3645 okay:
3646         if (_addrp)
3647                 *_addrp = addrp;
3648         return 0;
3649 }
3650
3651 /**
3652  * selinux_skb_peerlbl_sid - Determine the peer label of a packet
3653  * @skb: the packet
3654  * @family: protocol family
3655  * @sid: the packet's peer label SID
3656  *
3657  * Description:
3658  * Check the various different forms of network peer labeling and determine
3659  * the peer label/SID for the packet; most of the magic actually occurs in
3660  * the security server function security_net_peersid_cmp().  The function
3661  * returns zero if the value in @sid is valid (although it may be SECSID_NULL)
3662  * or -EACCES if @sid is invalid due to inconsistencies with the different
3663  * peer labels.
3664  *
3665  */
3666 static int selinux_skb_peerlbl_sid(struct sk_buff *skb, u16 family, u32 *sid)
3667 {
3668         int err;
3669         u32 xfrm_sid;
3670         u32 nlbl_sid;
3671         u32 nlbl_type;
3672
3673         selinux_skb_xfrm_sid(skb, &xfrm_sid);
3674         selinux_netlbl_skbuff_getsid(skb, family, &nlbl_type, &nlbl_sid);
3675
3676         err = security_net_peersid_resolve(nlbl_sid, nlbl_type, xfrm_sid, sid);
3677         if (unlikely(err)) {
3678                 printk(KERN_WARNING
3679                        "SELinux: failure in selinux_skb_peerlbl_sid(),"
3680                        " unable to determine packet's peer label\n");
3681                 return -EACCES;
3682         }
3683
3684         return 0;
3685 }
3686
3687 /* socket security operations */
3688 static int socket_has_perm(struct task_struct *task, struct socket *sock,
3689                            u32 perms)
3690 {
3691         struct inode_security_struct *isec;
3692         struct avc_audit_data ad;
3693         u32 sid;
3694         int err = 0;
3695
3696         isec = SOCK_INODE(sock)->i_security;
3697
3698         if (isec->sid == SECINITSID_KERNEL)
3699                 goto out;
3700         sid = task_sid(task);
3701
3702         AVC_AUDIT_DATA_INIT(&ad, NET);
3703         ad.u.net.sk = sock->sk;
3704         err = avc_has_perm(sid, isec->sid, isec->sclass, perms, &ad);
3705
3706 out:
3707         return err;
3708 }
3709
3710 static int selinux_socket_create(int family, int type,
3711                                  int protocol, int kern)
3712 {
3713         const struct cred *cred = current_cred();
3714         const struct task_security_struct *tsec = cred->security;
3715         u32 sid, newsid;
3716         u16 secclass;
3717         int err = 0;
3718
3719         if (kern)
3720                 goto out;
3721
3722         sid = tsec->sid;
3723         newsid = tsec->sockcreate_sid ?: sid;
3724
3725         secclass = socket_type_to_security_class(family, type, protocol);
3726         err = avc_has_perm(sid, newsid, secclass, SOCKET__CREATE, NULL);
3727
3728 out:
3729         return err;
3730 }
3731
3732 static int selinux_socket_post_create(struct socket *sock, int family,
3733                                       int type, int protocol, int kern)
3734 {
3735         const struct cred *cred = current_cred();
3736         const struct task_security_struct *tsec = cred->security;
3737         struct inode_security_struct *isec;
3738         struct sk_security_struct *sksec;
3739         u32 sid, newsid;
3740         int err = 0;
3741
3742         sid = tsec->sid;
3743         newsid = tsec->sockcreate_sid;
3744
3745         isec = SOCK_INODE(sock)->i_security;
3746
3747         if (kern)
3748                 isec->sid = SECINITSID_KERNEL;
3749         else if (newsid)
3750                 isec->sid = newsid;
3751         else
3752                 isec->sid = sid;
3753
3754         isec->sclass = socket_type_to_security_class(family, type, protocol);
3755         isec->initialized = 1;
3756
3757         if (sock->sk) {
3758                 sksec = sock->sk->sk_security;
3759                 sksec->sid = isec->sid;
3760                 sksec->sclass = isec->sclass;
3761                 err = selinux_netlbl_socket_post_create(sock);
3762         }
3763
3764         return err;
3765 }
3766
3767 /* Range of port numbers used to automatically bind.
3768    Need to determine whether we should perform a name_bind
3769    permission check between the socket and the port number. */
3770
3771 static int selinux_socket_bind(struct socket *sock, struct sockaddr *address, int addrlen)
3772 {
3773         u16 family;
3774         int err;
3775
3776         err = socket_has_perm(current, sock, SOCKET__BIND);
3777         if (err)
3778                 goto out;
3779
3780         /*
3781          * If PF_INET or PF_INET6, check name_bind permission for the port.
3782          * Multiple address binding for SCTP is not supported yet: we just
3783          * check the first address now.
3784          */
3785         family = sock->sk->sk_family;
3786         if (family == PF_INET || family == PF_INET6) {
3787                 char *addrp;
3788                 struct inode_security_struct *isec;
3789                 struct avc_audit_data ad;
3790                 struct sockaddr_in *addr4 = NULL;
3791                 struct sockaddr_in6 *addr6 = NULL;
3792                 unsigned short snum;
3793                 struct sock *sk = sock->sk;
3794                 u32 sid, node_perm;
3795
3796                 isec = SOCK_INODE(sock)->i_security;
3797
3798                 if (family == PF_INET) {
3799                         addr4 = (struct sockaddr_in *)address;
3800                         snum = ntohs(addr4->sin_port);
3801                         addrp = (char *)&addr4->sin_addr.s_addr;
3802                 } else {
3803                         addr6 = (struct sockaddr_in6 *)address;
3804                         snum = ntohs(addr6->sin6_port);
3805                         addrp = (char *)&addr6->sin6_addr.s6_addr;
3806                 }
3807
3808                 if (snum) {
3809                         int low, high;
3810
3811                         inet_get_local_port_range(&low, &high);
3812
3813                         if (snum < max(PROT_SOCK, low) || snum > high) {
3814                                 err = sel_netport_sid(sk->sk_protocol,
3815                                                       snum, &sid);
3816                                 if (err)
3817                                         goto out;
3818                                 AVC_AUDIT_DATA_INIT(&ad, NET);
3819                                 ad.u.net.sport = htons(snum);
3820                                 ad.u.net.family = family;
3821                                 err = avc_has_perm(isec->sid, sid,
3822                                                    isec->sclass,
3823                                                    SOCKET__NAME_BIND, &ad);
3824                                 if (err)
3825                                         goto out;
3826                         }
3827                 }
3828
3829                 switch (isec->sclass) {
3830                 case SECCLASS_TCP_SOCKET:
3831                         node_perm = TCP_SOCKET__NODE_BIND;
3832                         break;
3833
3834                 case SECCLASS_UDP_SOCKET:
3835                         node_perm = UDP_SOCKET__NODE_BIND;
3836                         break;
3837
3838                 case SECCLASS_DCCP_SOCKET:
3839                         node_perm = DCCP_SOCKET__NODE_BIND;
3840                         break;
3841
3842                 default:
3843                         node_perm = RAWIP_SOCKET__NODE_BIND;
3844                         break;
3845                 }
3846
3847                 err = sel_netnode_sid(addrp, family, &sid);
3848                 if (err)
3849                         goto out;
3850
3851                 AVC_AUDIT_DATA_INIT(&ad, NET);
3852                 ad.u.net.sport = htons(snum);
3853                 ad.u.net.family = family;
3854
3855                 if (family == PF_INET)
3856                         ad.u.net.v4info.saddr = addr4->sin_addr.s_addr;
3857                 else
3858                         ipv6_addr_copy(&ad.u.net.v6info.saddr, &addr6->sin6_addr);
3859
3860                 err = avc_has_perm(isec->sid, sid,
3861                                    isec->sclass, node_perm, &ad);
3862                 if (err)
3863                         goto out;
3864         }
3865 out:
3866         return err;
3867 }
3868
3869 static int selinux_socket_connect(struct socket *sock, struct sockaddr *address, int addrlen)
3870 {
3871         struct sock *sk = sock->sk;
3872         struct inode_security_struct *isec;
3873         int err;
3874
3875         err = socket_has_perm(current, sock, SOCKET__CONNECT);
3876         if (err)
3877                 return err;
3878
3879         /*
3880          * If a TCP or DCCP socket, check name_connect permission for the port.
3881          */
3882         isec = SOCK_INODE(sock)->i_security;
3883         if (isec->sclass == SECCLASS_TCP_SOCKET ||
3884             isec->sclass == SECCLASS_DCCP_SOCKET) {
3885                 struct avc_audit_data ad;
3886                 struct sockaddr_in *addr4 = NULL;
3887                 struct sockaddr_in6 *addr6 = NULL;
3888                 unsigned short snum;
3889                 u32 sid, perm;
3890
3891                 if (sk->sk_family == PF_INET) {
3892                         addr4 = (struct sockaddr_in *)address;
3893                         if (addrlen < sizeof(struct sockaddr_in))
3894                                 return -EINVAL;
3895                         snum = ntohs(addr4->sin_port);
3896                 } else {
3897                         addr6 = (struct sockaddr_in6 *)address;
3898                         if (addrlen < SIN6_LEN_RFC2133)
3899                                 return -EINVAL;
3900                         snum = ntohs(addr6->sin6_port);
3901                 }
3902
3903                 err = sel_netport_sid(sk->sk_protocol, snum, &sid);
3904                 if (err)
3905                         goto out;
3906
3907                 perm = (isec->sclass == SECCLASS_TCP_SOCKET) ?
3908                        TCP_SOCKET__NAME_CONNECT : DCCP_SOCKET__NAME_CONNECT;
3909
3910                 AVC_AUDIT_DATA_INIT(&ad, NET);
3911                 ad.u.net.dport = htons(snum);
3912                 ad.u.net.family = sk->sk_family;
3913                 err = avc_has_perm(isec->sid, sid, isec->sclass, perm, &ad);
3914                 if (err)
3915                         goto out;
3916         }
3917
3918         err = selinux_netlbl_socket_connect(sk, address);
3919
3920 out:
3921         return err;
3922 }
3923
3924 static int selinux_socket_listen(struct socket *sock, int backlog)
3925 {
3926         return socket_has_perm(current, sock, SOCKET__LISTEN);
3927 }
3928
3929 static int selinux_socket_accept(struct socket *sock, struct socket *newsock)
3930 {
3931         int err;
3932         struct inode_security_struct *isec;
3933         struct inode_security_struct *newisec;
3934
3935         err = socket_has_perm(current, sock, SOCKET__ACCEPT);
3936         if (err)
3937                 return err;
3938
3939         newisec = SOCK_INODE(newsock)->i_security;
3940
3941         isec = SOCK_INODE(sock)->i_security;
3942         newisec->sclass = isec->sclass;
3943         newisec->sid = isec->sid;
3944         newisec->initialized = 1;
3945
3946         return 0;
3947 }
3948
3949 static int selinux_socket_sendmsg(struct socket *sock, struct msghdr *msg,
3950                                   int size)
3951 {
3952         int rc;
3953
3954         rc = socket_has_perm(current, sock, SOCKET__WRITE);
3955         if (rc)
3956                 return rc;
3957
3958         return selinux_netlbl_inode_permission(SOCK_INODE(sock), MAY_WRITE);
3959 }
3960
3961 static int selinux_socket_recvmsg(struct socket *sock, struct msghdr *msg,
3962                                   int size, int flags)
3963 {
3964         return socket_has_perm(current, sock, SOCKET__READ);
3965 }
3966
3967 static int selinux_socket_getsockname(struct socket *sock)
3968 {
3969         return socket_has_perm(current, sock, SOCKET__GETATTR);
3970 }
3971
3972 static int selinux_socket_getpeername(struct socket *sock)
3973 {
3974         return socket_has_perm(current, sock, SOCKET__GETATTR);
3975 }
3976
3977 static int selinux_socket_setsockopt(struct socket *sock, int level, int optname)
3978 {
3979         int err;
3980
3981         err = socket_has_perm(current, sock, SOCKET__SETOPT);
3982         if (err)
3983                 return err;
3984
3985         return selinux_netlbl_socket_setsockopt(sock, level, optname);
3986 }
3987
3988 static int selinux_socket_getsockopt(struct socket *sock, int level,
3989                                      int optname)
3990 {
3991         return socket_has_perm(current, sock, SOCKET__GETOPT);
3992 }
3993
3994 static int selinux_socket_shutdown(struct socket *sock, int how)
3995 {
3996         return socket_has_perm(current, sock, SOCKET__SHUTDOWN);
3997 }
3998
3999 static int selinux_socket_unix_stream_connect(struct socket *sock,
4000                                               struct socket *other,
4001                                               struct sock *newsk)
4002 {
4003         struct sk_security_struct *ssec;
4004         struct inode_security_struct *isec;
4005         struct inode_security_struct *other_isec;
4006         struct avc_audit_data ad;
4007         int err;
4008
4009         err = secondary_ops->unix_stream_connect(sock, other, newsk);
4010         if (err)
4011                 return err;
4012
4013         isec = SOCK_INODE(sock)->i_security;
4014         other_isec = SOCK_INODE(other)->i_security;
4015
4016         AVC_AUDIT_DATA_INIT(&ad, NET);
4017         ad.u.net.sk = other->sk;
4018
4019         err = avc_has_perm(isec->sid, other_isec->sid,
4020                            isec->sclass,
4021                            UNIX_STREAM_SOCKET__CONNECTTO, &ad);
4022         if (err)
4023                 return err;
4024
4025         /* connecting socket */
4026         ssec = sock->sk->sk_security;
4027         ssec->peer_sid = other_isec->sid;
4028
4029         /* server child socket */
4030         ssec = newsk->sk_security;
4031         ssec->peer_sid = isec->sid;
4032         err = security_sid_mls_copy(other_isec->sid, ssec->peer_sid, &ssec->sid);
4033
4034         return err;
4035 }
4036
4037 static int selinux_socket_unix_may_send(struct socket *sock,
4038                                         struct socket *other)
4039 {
4040         struct inode_security_struct *isec;
4041         struct inode_security_struct *other_isec;
4042         struct avc_audit_data ad;
4043         int err;
4044
4045         isec = SOCK_INODE(sock)->i_security;
4046         other_isec = SOCK_INODE(other)->i_security;
4047
4048         AVC_AUDIT_DATA_INIT(&ad, NET);
4049         ad.u.net.sk = other->sk;
4050
4051         err = avc_has_perm(isec->sid, other_isec->sid,
4052                            isec->sclass, SOCKET__SENDTO, &ad);
4053         if (err)
4054                 return err;
4055
4056         return 0;
4057 }
4058
4059 static int selinux_inet_sys_rcv_skb(int ifindex, char *addrp, u16 family,
4060                                     u32 peer_sid,
4061                                     struct avc_audit_data *ad)
4062 {
4063         int err;
4064         u32 if_sid;
4065         u32 node_sid;
4066
4067         err = sel_netif_sid(ifindex, &if_sid);
4068         if (err)
4069                 return err;
4070         err = avc_has_perm(peer_sid, if_sid,
4071                            SECCLASS_NETIF, NETIF__INGRESS, ad);
4072         if (err)
4073                 return err;
4074
4075         err = sel_netnode_sid(addrp, family, &node_sid);
4076         if (err)
4077                 return err;
4078         return avc_has_perm(peer_sid, node_sid,
4079                             SECCLASS_NODE, NODE__RECVFROM, ad);
4080 }
4081
4082 static int selinux_sock_rcv_skb_iptables_compat(struct sock *sk,
4083                                                 struct sk_buff *skb,
4084                                                 struct avc_audit_data *ad,
4085                                                 u16 family,
4086                                                 char *addrp)
4087 {
4088         int err;
4089         struct sk_security_struct *sksec = sk->sk_security;
4090         u16 sk_class;
4091         u32 netif_perm, node_perm, recv_perm;
4092         u32 port_sid, node_sid, if_sid, sk_sid;
4093
4094         sk_sid = sksec->sid;
4095         sk_class = sksec->sclass;
4096
4097         switch (sk_class) {
4098         case SECCLASS_UDP_SOCKET:
4099                 netif_perm = NETIF__UDP_RECV;
4100                 node_perm = NODE__UDP_RECV;
4101                 recv_perm = UDP_SOCKET__RECV_MSG;
4102                 break;
4103         case SECCLASS_TCP_SOCKET:
4104                 netif_perm = NETIF__TCP_RECV;
4105                 node_perm = NODE__TCP_RECV;
4106                 recv_perm = TCP_SOCKET__RECV_MSG;
4107                 break;
4108         case SECCLASS_DCCP_SOCKET:
4109                 netif_perm = NETIF__DCCP_RECV;
4110                 node_perm = NODE__DCCP_RECV;
4111                 recv_perm = DCCP_SOCKET__RECV_MSG;
4112                 break;
4113         default:
4114                 netif_perm = NETIF__RAWIP_RECV;
4115                 node_perm = NODE__RAWIP_RECV;
4116                 recv_perm = 0;
4117                 break;
4118         }
4119
4120         err = sel_netif_sid(skb->iif, &if_sid);
4121         if (err)
4122                 return err;
4123         err = avc_has_perm(sk_sid, if_sid, SECCLASS_NETIF, netif_perm, ad);
4124         if (err)
4125                 return err;
4126
4127         err = sel_netnode_sid(addrp, family, &node_sid);
4128         if (err)
4129                 return err;
4130         err = avc_has_perm(sk_sid, node_sid, SECCLASS_NODE, node_perm, ad);
4131         if (err)
4132                 return err;
4133
4134         if (!recv_perm)
4135                 return 0;
4136         err = sel_netport_sid(sk->sk_protocol,
4137                               ntohs(ad->u.net.sport), &port_sid);
4138         if (unlikely(err)) {
4139                 printk(KERN_WARNING
4140                        "SELinux: failure in"
4141                        " selinux_sock_rcv_skb_iptables_compat(),"
4142                        " network port label not found\n");
4143                 return err;
4144         }
4145         return avc_has_perm(sk_sid, port_sid, sk_class, recv_perm, ad);
4146 }
4147
4148 static int selinux_sock_rcv_skb_compat(struct sock *sk, struct sk_buff *skb,
4149                                        u16 family)
4150 {
4151         int err = 0;
4152         struct sk_security_struct *sksec = sk->sk_security;
4153         u32 peer_sid;
4154         u32 sk_sid = sksec->sid;
4155         struct avc_audit_data ad;
4156         char *addrp;
4157
4158         AVC_AUDIT_DATA_INIT(&ad, NET);
4159         ad.u.net.netif = skb->iif;
4160         ad.u.net.family = family;
4161         err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL);
4162         if (err)
4163                 return err;
4164
4165         if (selinux_compat_net)
4166                 err = selinux_sock_rcv_skb_iptables_compat(sk, skb, &ad,
4167                                                            family, addrp);
4168         else if (selinux_secmark_enabled())
4169                 err = avc_has_perm(sk_sid, skb->secmark, SECCLASS_PACKET,
4170                                    PACKET__RECV, &ad);
4171         if (err)
4172                 return err;
4173
4174         if (selinux_policycap_netpeer) {
4175                 err = selinux_skb_peerlbl_sid(skb, family, &peer_sid);
4176                 if (err)
4177                         return err;
4178                 err = avc_has_perm(sk_sid, peer_sid,
4179                                    SECCLASS_PEER, PEER__RECV, &ad);
4180                 if (err)
4181                         selinux_netlbl_err(skb, err, 0);
4182         } else {
4183                 err = selinux_netlbl_sock_rcv_skb(sksec, skb, family, &ad);
4184                 if (err)
4185                         return err;
4186                 err = selinux_xfrm_sock_rcv_skb(sksec->sid, skb, &ad);
4187         }
4188
4189         return err;
4190 }
4191
4192 static int selinux_socket_sock_rcv_skb(struct sock *sk, struct sk_buff *skb)
4193 {
4194         int err;
4195         struct sk_security_struct *sksec = sk->sk_security;
4196         u16 family = sk->sk_family;
4197         u32 sk_sid = sksec->sid;
4198         struct avc_audit_data ad;
4199         char *addrp;
4200         u8 secmark_active;
4201         u8 peerlbl_active;
4202
4203         if (family != PF_INET && family != PF_INET6)
4204                 return 0;
4205
4206         /* Handle mapped IPv4 packets arriving via IPv6 sockets */
4207         if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
4208                 family = PF_INET;
4209
4210         /* If any sort of compatibility mode is enabled then handoff processing
4211          * to the selinux_sock_rcv_skb_compat() function to deal with the
4212          * special handling.  We do this in an attempt to keep this function
4213          * as fast and as clean as possible. */
4214         if (selinux_compat_net || !selinux_policycap_netpeer)
4215                 return selinux_sock_rcv_skb_compat(sk, skb, family);
4216
4217         secmark_active = selinux_secmark_enabled();
4218         peerlbl_active = netlbl_enabled() || selinux_xfrm_enabled();
4219         if (!secmark_active && !peerlbl_active)
4220                 return 0;
4221
4222         AVC_AUDIT_DATA_INIT(&ad, NET);
4223         ad.u.net.netif = skb->iif;
4224         ad.u.net.family = family;
4225         err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL);
4226         if (err)
4227                 return err;
4228
4229         if (peerlbl_active) {
4230                 u32 peer_sid;
4231
4232                 err = selinux_skb_peerlbl_sid(skb, family, &peer_sid);
4233                 if (err)
4234                         return err;
4235                 err = selinux_inet_sys_rcv_skb(skb->iif, addrp, family,
4236                                                peer_sid, &ad);
4237                 if (err) {
4238                         selinux_netlbl_err(skb, err, 0);
4239                         return err;
4240                 }
4241                 err = avc_has_perm(sk_sid, peer_sid, SECCLASS_PEER,
4242                                    PEER__RECV, &ad);
4243                 if (err)
4244                         selinux_netlbl_err(skb, err, 0);
4245         }
4246
4247         if (secmark_active) {
4248                 err = avc_has_perm(sk_sid, skb->secmark, SECCLASS_PACKET,
4249                                    PACKET__RECV, &ad);
4250                 if (err)
4251                         return err;
4252         }
4253
4254         return err;
4255 }
4256
4257 static int selinux_socket_getpeersec_stream(struct socket *sock, char __user *optval,
4258                                             int __user *optlen, unsigned len)
4259 {
4260         int err = 0;
4261         char *scontext;
4262         u32 scontext_len;
4263         struct sk_security_struct *ssec;
4264         struct inode_security_struct *isec;
4265         u32 peer_sid = SECSID_NULL;
4266
4267         isec = SOCK_INODE(sock)->i_security;
4268
4269         if (isec->sclass == SECCLASS_UNIX_STREAM_SOCKET ||
4270             isec->sclass == SECCLASS_TCP_SOCKET) {
4271                 ssec = sock->sk->sk_security;
4272                 peer_sid = ssec->peer_sid;
4273         }
4274         if (peer_sid == SECSID_NULL) {
4275                 err = -ENOPROTOOPT;
4276                 goto out;
4277         }
4278
4279         err = security_sid_to_context(peer_sid, &scontext, &scontext_len);
4280
4281         if (err)
4282                 goto out;
4283
4284         if (scontext_len > len) {
4285                 err = -ERANGE;
4286                 goto out_len;
4287         }
4288
4289         if (copy_to_user(optval, scontext, scontext_len))
4290                 err = -EFAULT;
4291
4292 out_len:
4293         if (put_user(scontext_len, optlen))
4294                 err = -EFAULT;
4295
4296         kfree(scontext);
4297 out:
4298         return err;
4299 }
4300
4301 static int selinux_socket_getpeersec_dgram(struct socket *sock, struct sk_buff *skb, u32 *secid)
4302 {
4303         u32 peer_secid = SECSID_NULL;
4304         u16 family;
4305
4306         if (skb && skb->protocol == htons(ETH_P_IP))
4307                 family = PF_INET;
4308         else if (skb && skb->protocol == htons(ETH_P_IPV6))
4309                 family = PF_INET6;
4310         else if (sock)
4311                 family = sock->sk->sk_family;
4312         else
4313                 goto out;
4314
4315         if (sock && family == PF_UNIX)
4316                 selinux_inode_getsecid(SOCK_INODE(sock), &peer_secid);
4317         else if (skb)
4318                 selinux_skb_peerlbl_sid(skb, family, &peer_secid);
4319
4320 out:
4321         *secid = peer_secid;
4322         if (peer_secid == SECSID_NULL)
4323                 return -EINVAL;
4324         return 0;
4325 }
4326
4327 static int selinux_sk_alloc_security(struct sock *sk, int family, gfp_t priority)
4328 {
4329         return sk_alloc_security(sk, family, priority);
4330 }
4331
4332 static void selinux_sk_free_security(struct sock *sk)
4333 {
4334         sk_free_security(sk);
4335 }
4336
4337 static void selinux_sk_clone_security(const struct sock *sk, struct sock *newsk)
4338 {
4339         struct sk_security_struct *ssec = sk->sk_security;
4340         struct sk_security_struct *newssec = newsk->sk_security;
4341
4342         newssec->sid = ssec->sid;
4343         newssec->peer_sid = ssec->peer_sid;
4344         newssec->sclass = ssec->sclass;
4345
4346         selinux_netlbl_sk_security_reset(newssec, newsk->sk_family);
4347 }
4348
4349 static void selinux_sk_getsecid(struct sock *sk, u32 *secid)
4350 {
4351         if (!sk)
4352                 *secid = SECINITSID_ANY_SOCKET;
4353         else {
4354                 struct sk_security_struct *sksec = sk->sk_security;
4355
4356                 *secid = sksec->sid;
4357         }
4358 }
4359
4360 static void selinux_sock_graft(struct sock *sk, struct socket *parent)
4361 {
4362         struct inode_security_struct *isec = SOCK_INODE(parent)->i_security;
4363         struct sk_security_struct *sksec = sk->sk_security;
4364
4365         if (sk->sk_family == PF_INET || sk->sk_family == PF_INET6 ||
4366             sk->sk_family == PF_UNIX)
4367                 isec->sid = sksec->sid;
4368         sksec->sclass = isec->sclass;
4369 }
4370
4371 static int selinux_inet_conn_request(struct sock *sk, struct sk_buff *skb,
4372                                      struct request_sock *req)
4373 {
4374         struct sk_security_struct *sksec = sk->sk_security;
4375         int err;
4376         u16 family = sk->sk_family;
4377         u32 newsid;
4378         u32 peersid;
4379
4380         /* handle mapped IPv4 packets arriving via IPv6 sockets */
4381         if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
4382                 family = PF_INET;
4383
4384         err = selinux_skb_peerlbl_sid(skb, family, &peersid);
4385         if (err)
4386                 return err;
4387         if (peersid == SECSID_NULL) {
4388                 req->secid = sksec->sid;
4389                 req->peer_secid = SECSID_NULL;
4390                 return 0;
4391         }
4392
4393         err = security_sid_mls_copy(sksec->sid, peersid, &newsid);
4394         if (err)
4395                 return err;
4396
4397         req->secid = newsid;
4398         req->peer_secid = peersid;
4399         return 0;
4400 }
4401
4402 static void selinux_inet_csk_clone(struct sock *newsk,
4403                                    const struct request_sock *req)
4404 {
4405         struct sk_security_struct *newsksec = newsk->sk_security;
4406
4407         newsksec->sid = req->secid;
4408         newsksec->peer_sid = req->peer_secid;
4409         /* NOTE: Ideally, we should also get the isec->sid for the
4410            new socket in sync, but we don't have the isec available yet.
4411            So we will wait until sock_graft to do it, by which
4412            time it will have been created and available. */
4413
4414         /* We don't need to take any sort of lock here as we are the only
4415          * thread with access to newsksec */
4416         selinux_netlbl_sk_security_reset(newsksec, req->rsk_ops->family);
4417 }
4418
4419 static void selinux_inet_conn_established(struct sock *sk, struct sk_buff *skb)
4420 {
4421         u16 family = sk->sk_family;
4422         struct sk_security_struct *sksec = sk->sk_security;
4423
4424         /* handle mapped IPv4 packets arriving via IPv6 sockets */
4425         if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
4426                 family = PF_INET;
4427
4428         selinux_skb_peerlbl_sid(skb, family, &sksec->peer_sid);
4429
4430         selinux_netlbl_inet_conn_established(sk, family);
4431 }
4432
4433 static void selinux_req_classify_flow(const struct request_sock *req,
4434                                       struct flowi *fl)
4435 {
4436         fl->secid = req->secid;
4437 }
4438
4439 static int selinux_nlmsg_perm(struct sock *sk, struct sk_buff *skb)
4440 {
4441         int err = 0;
4442         u32 perm;
4443         struct nlmsghdr *nlh;
4444         struct socket *sock = sk->sk_socket;
4445         struct inode_security_struct *isec = SOCK_INODE(sock)->i_security;
4446
4447         if (skb->len < NLMSG_SPACE(0)) {
4448                 err = -EINVAL;
4449                 goto out;
4450         }
4451         nlh = nlmsg_hdr(skb);
4452
4453         err = selinux_nlmsg_lookup(isec->sclass, nlh->nlmsg_type, &perm);
4454         if (err) {
4455                 if (err == -EINVAL) {
4456                         audit_log(current->audit_context, GFP_KERNEL, AUDIT_SELINUX_ERR,
4457                                   "SELinux:  unrecognized netlink message"
4458                                   " type=%hu for sclass=%hu\n",
4459                                   nlh->nlmsg_type, isec->sclass);
4460                         if (!selinux_enforcing || security_get_allow_unknown())
4461                                 err = 0;
4462                 }
4463
4464                 /* Ignore */
4465                 if (err == -ENOENT)
4466                         err = 0;
4467                 goto out;
4468         }
4469
4470         err = socket_has_perm(current, sock, perm);
4471 out:
4472         return err;
4473 }
4474
4475 #ifdef CONFIG_NETFILTER
4476
4477 static unsigned int selinux_ip_forward(struct sk_buff *skb, int ifindex,
4478                                        u16 family)
4479 {
4480         int err;
4481         char *addrp;
4482         u32 peer_sid;
4483         struct avc_audit_data ad;
4484         u8 secmark_active;
4485         u8 netlbl_active;
4486         u8 peerlbl_active;
4487
4488         if (!selinux_policycap_netpeer)
4489                 return NF_ACCEPT;
4490
4491         secmark_active = selinux_secmark_enabled();
4492         netlbl_active = netlbl_enabled();
4493         peerlbl_active = netlbl_active || selinux_xfrm_enabled();
4494         if (!secmark_active && !peerlbl_active)
4495                 return NF_ACCEPT;
4496
4497         if (selinux_skb_peerlbl_sid(skb, family, &peer_sid) != 0)
4498                 return NF_DROP;
4499
4500         AVC_AUDIT_DATA_INIT(&ad, NET);
4501         ad.u.net.netif = ifindex;
4502         ad.u.net.family = family;
4503         if (selinux_parse_skb(skb, &ad, &addrp, 1, NULL) != 0)
4504                 return NF_DROP;
4505
4506         if (peerlbl_active) {
4507                 err = selinux_inet_sys_rcv_skb(ifindex, addrp, family,
4508                                                peer_sid, &ad);
4509                 if (err) {
4510                         selinux_netlbl_err(skb, err, 1);
4511                         return NF_DROP;
4512                 }
4513         }
4514
4515         if (secmark_active)
4516                 if (avc_has_perm(peer_sid, skb->secmark,
4517                                  SECCLASS_PACKET, PACKET__FORWARD_IN, &ad))
4518                         return NF_DROP;
4519
4520         if (netlbl_active)
4521                 /* we do this in the FORWARD path and not the POST_ROUTING
4522                  * path because we want to make sure we apply the necessary
4523                  * labeling before IPsec is applied so we can leverage AH
4524                  * protection */
4525                 if (selinux_netlbl_skbuff_setsid(skb, family, peer_sid) != 0)
4526                         return NF_DROP;
4527
4528         return NF_ACCEPT;
4529 }
4530
4531 static unsigned int selinux_ipv4_forward(unsigned int hooknum,
4532                                          struct sk_buff *skb,
4533                                          const struct net_device *in,
4534                                          const struct net_device *out,
4535                                          int (*okfn)(struct sk_buff *))
4536 {
4537         return selinux_ip_forward(skb, in->ifindex, PF_INET);
4538 }
4539
4540 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
4541 static unsigned int selinux_ipv6_forward(unsigned int hooknum,
4542                                          struct sk_buff *skb,
4543                                          const struct net_device *in,
4544                                          const struct net_device *out,
4545                                          int (*okfn)(struct sk_buff *))
4546 {
4547         return selinux_ip_forward(skb, in->ifindex, PF_INET6);
4548 }
4549 #endif  /* IPV6 */
4550
4551 static unsigned int selinux_ip_output(struct sk_buff *skb,
4552                                       u16 family)
4553 {
4554         u32 sid;
4555
4556         if (!netlbl_enabled())
4557                 return NF_ACCEPT;
4558
4559         /* we do this in the LOCAL_OUT path and not the POST_ROUTING path
4560          * because we want to make sure we apply the necessary labeling
4561          * before IPsec is applied so we can leverage AH protection */
4562         if (skb->sk) {
4563                 struct sk_security_struct *sksec = skb->sk->sk_security;
4564                 sid = sksec->sid;
4565         } else
4566                 sid = SECINITSID_KERNEL;
4567         if (selinux_netlbl_skbuff_setsid(skb, family, sid) != 0)
4568                 return NF_DROP;
4569
4570         return NF_ACCEPT;
4571 }
4572
4573 static unsigned int selinux_ipv4_output(unsigned int hooknum,
4574                                         struct sk_buff *skb,
4575                                         const struct net_device *in,
4576                                         const struct net_device *out,
4577                                         int (*okfn)(struct sk_buff *))
4578 {
4579         return selinux_ip_output(skb, PF_INET);
4580 }
4581
4582 static int selinux_ip_postroute_iptables_compat(struct sock *sk,
4583                                                 int ifindex,
4584                                                 struct avc_audit_data *ad,
4585                                                 u16 family, char *addrp)
4586 {
4587         int err;
4588         struct sk_security_struct *sksec = sk->sk_security;
4589         u16 sk_class;
4590         u32 netif_perm, node_perm, send_perm;
4591         u32 port_sid, node_sid, if_sid, sk_sid;
4592
4593         sk_sid = sksec->sid;
4594         sk_class = sksec->sclass;
4595
4596         switch (sk_class) {
4597         case SECCLASS_UDP_SOCKET:
4598                 netif_perm = NETIF__UDP_SEND;
4599                 node_perm = NODE__UDP_SEND;
4600                 send_perm = UDP_SOCKET__SEND_MSG;
4601                 break;
4602         case SECCLASS_TCP_SOCKET:
4603                 netif_perm = NETIF__TCP_SEND;
4604                 node_perm = NODE__TCP_SEND;
4605                 send_perm = TCP_SOCKET__SEND_MSG;
4606                 break;
4607         case SECCLASS_DCCP_SOCKET:
4608                 netif_perm = NETIF__DCCP_SEND;
4609                 node_perm = NODE__DCCP_SEND;
4610                 send_perm = DCCP_SOCKET__SEND_MSG;
4611                 break;
4612         default:
4613                 netif_perm = NETIF__RAWIP_SEND;
4614                 node_perm = NODE__RAWIP_SEND;
4615                 send_perm = 0;
4616                 break;
4617         }
4618
4619         err = sel_netif_sid(ifindex, &if_sid);
4620         if (err)
4621                 return err;
4622         err = avc_has_perm(sk_sid, if_sid, SECCLASS_NETIF, netif_perm, ad);
4623                 return err;
4624
4625         err = sel_netnode_sid(addrp, family, &node_sid);
4626         if (err)
4627                 return err;
4628         err = avc_has_perm(sk_sid, node_sid, SECCLASS_NODE, node_perm, ad);
4629         if (err)
4630                 return err;
4631
4632         if (send_perm != 0)
4633                 return 0;
4634
4635         err = sel_netport_sid(sk->sk_protocol,
4636                               ntohs(ad->u.net.dport), &port_sid);
4637         if (unlikely(err)) {
4638                 printk(KERN_WARNING
4639                        "SELinux: failure in"
4640                        " selinux_ip_postroute_iptables_compat(),"
4641                        " network port label not found\n");
4642                 return err;
4643         }
4644         return avc_has_perm(sk_sid, port_sid, sk_class, send_perm, ad);
4645 }
4646
4647 static unsigned int selinux_ip_postroute_compat(struct sk_buff *skb,
4648                                                 int ifindex,
4649                                                 u16 family)
4650 {
4651         struct sock *sk = skb->sk;
4652         struct sk_security_struct *sksec;
4653         struct avc_audit_data ad;
4654         char *addrp;
4655         u8 proto;
4656
4657         if (sk == NULL)
4658                 return NF_ACCEPT;
4659         sksec = sk->sk_security;
4660
4661         AVC_AUDIT_DATA_INIT(&ad, NET);
4662         ad.u.net.netif = ifindex;
4663         ad.u.net.family = family;
4664         if (selinux_parse_skb(skb, &ad, &addrp, 0, &proto))
4665                 return NF_DROP;
4666
4667         if (selinux_compat_net) {
4668                 if (selinux_ip_postroute_iptables_compat(skb->sk, ifindex,
4669                                                          &ad, family, addrp))
4670                         return NF_DROP;
4671         } else if (selinux_secmark_enabled()) {
4672                 if (avc_has_perm(sksec->sid, skb->secmark,
4673                                  SECCLASS_PACKET, PACKET__SEND, &ad))
4674                         return NF_DROP;
4675         }
4676
4677         if (selinux_policycap_netpeer)
4678                 if (selinux_xfrm_postroute_last(sksec->sid, skb, &ad, proto))
4679                         return NF_DROP;
4680
4681         return NF_ACCEPT;
4682 }
4683
4684 static unsigned int selinux_ip_postroute(struct sk_buff *skb, int ifindex,
4685                                          u16 family)
4686 {
4687         u32 secmark_perm;
4688         u32 peer_sid;
4689         struct sock *sk;
4690         struct avc_audit_data ad;
4691         char *addrp;
4692         u8 secmark_active;
4693         u8 peerlbl_active;
4694
4695         /* If any sort of compatibility mode is enabled then handoff processing
4696          * to the selinux_ip_postroute_compat() function to deal with the
4697          * special handling.  We do this in an attempt to keep this function
4698          * as fast and as clean as possible. */
4699         if (selinux_compat_net || !selinux_policycap_netpeer)
4700                 return selinux_ip_postroute_compat(skb, ifindex, family);
4701 #ifdef CONFIG_XFRM
4702         /* If skb->dst->xfrm is non-NULL then the packet is undergoing an IPsec
4703          * packet transformation so allow the packet to pass without any checks
4704          * since we'll have another chance to perform access control checks
4705          * when the packet is on it's final way out.
4706          * NOTE: there appear to be some IPv6 multicast cases where skb->dst
4707          *       is NULL, in this case go ahead and apply access control. */
4708         if (skb->dst != NULL && skb->dst->xfrm != NULL)
4709                 return NF_ACCEPT;
4710 #endif
4711         secmark_active = selinux_secmark_enabled();
4712         peerlbl_active = netlbl_enabled() || selinux_xfrm_enabled();
4713         if (!secmark_active && !peerlbl_active)
4714                 return NF_ACCEPT;
4715
4716         /* if the packet is being forwarded then get the peer label from the
4717          * packet itself; otherwise check to see if it is from a local
4718          * application or the kernel, if from an application get the peer label
4719          * from the sending socket, otherwise use the kernel's sid */
4720         sk = skb->sk;
4721         if (sk == NULL) {
4722                 switch (family) {
4723                 case PF_INET:
4724                         if (IPCB(skb)->flags & IPSKB_FORWARDED)
4725                                 secmark_perm = PACKET__FORWARD_OUT;
4726                         else
4727                                 secmark_perm = PACKET__SEND;
4728                         break;
4729                 case PF_INET6:
4730                         if (IP6CB(skb)->flags & IP6SKB_FORWARDED)
4731                                 secmark_perm = PACKET__FORWARD_OUT;
4732                         else
4733                                 secmark_perm = PACKET__SEND;
4734                         break;
4735                 default:
4736                         return NF_DROP;
4737                 }
4738                 if (secmark_perm == PACKET__FORWARD_OUT) {
4739                         if (selinux_skb_peerlbl_sid(skb, family, &peer_sid))
4740                                 return NF_DROP;
4741                 } else
4742                         peer_sid = SECINITSID_KERNEL;
4743         } else {
4744                 struct sk_security_struct *sksec = sk->sk_security;
4745                 peer_sid = sksec->sid;
4746                 secmark_perm = PACKET__SEND;
4747         }
4748
4749         AVC_AUDIT_DATA_INIT(&ad, NET);
4750         ad.u.net.netif = ifindex;
4751         ad.u.net.family = family;
4752         if (selinux_parse_skb(skb, &ad, &addrp, 0, NULL))
4753                 return NF_DROP;
4754
4755         if (secmark_active)
4756                 if (avc_has_perm(peer_sid, skb->secmark,
4757                                  SECCLASS_PACKET, secmark_perm, &ad))
4758                         return NF_DROP;
4759
4760         if (peerlbl_active) {
4761                 u32 if_sid;
4762                 u32 node_sid;
4763
4764                 if (sel_netif_sid(ifindex, &if_sid))
4765                         return NF_DROP;
4766                 if (avc_has_perm(peer_sid, if_sid,
4767                                  SECCLASS_NETIF, NETIF__EGRESS, &ad))
4768                         return NF_DROP;
4769
4770                 if (sel_netnode_sid(addrp, family, &node_sid))
4771                         return NF_DROP;
4772                 if (avc_has_perm(peer_sid, node_sid,
4773                                  SECCLASS_NODE, NODE__SENDTO, &ad))
4774                         return NF_DROP;
4775         }
4776
4777         return NF_ACCEPT;
4778 }
4779
4780 static unsigned int selinux_ipv4_postroute(unsigned int hooknum,
4781                                            struct sk_buff *skb,
4782                                            const struct net_device *in,
4783                                            const struct net_device *out,
4784                                            int (*okfn)(struct sk_buff *))
4785 {
4786         return selinux_ip_postroute(skb, out->ifindex, PF_INET);
4787 }
4788
4789 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
4790 static unsigned int selinux_ipv6_postroute(unsigned int hooknum,
4791                                            struct sk_buff *skb,
4792                                            const struct net_device *in,
4793                                            const struct net_device *out,
4794                                            int (*okfn)(struct sk_buff *))
4795 {
4796         return selinux_ip_postroute(skb, out->ifindex, PF_INET6);
4797 }
4798 #endif  /* IPV6 */
4799
4800 #endif  /* CONFIG_NETFILTER */
4801
4802 static int selinux_netlink_send(struct sock *sk, struct sk_buff *skb)
4803 {
4804         int err;
4805
4806         err = secondary_ops->netlink_send(sk, skb);
4807         if (err)
4808                 return err;
4809
4810         if (policydb_loaded_version >= POLICYDB_VERSION_NLCLASS)
4811                 err = selinux_nlmsg_perm(sk, skb);
4812
4813         return err;
4814 }
4815
4816 static int selinux_netlink_recv(struct sk_buff *skb, int capability)
4817 {
4818         int err;
4819         struct avc_audit_data ad;
4820
4821         err = secondary_ops->netlink_recv(skb, capability);
4822         if (err)
4823                 return err;
4824
4825         AVC_AUDIT_DATA_INIT(&ad, CAP);
4826         ad.u.cap = capability;
4827
4828         return avc_has_perm(NETLINK_CB(skb).sid, NETLINK_CB(skb).sid,
4829                             SECCLASS_CAPABILITY, CAP_TO_MASK(capability), &ad);
4830 }
4831
4832 static int ipc_alloc_security(struct task_struct *task,
4833                               struct kern_ipc_perm *perm,
4834                               u16 sclass)
4835 {
4836         struct ipc_security_struct *isec;
4837         u32 sid;
4838
4839         isec = kzalloc(sizeof(struct ipc_security_struct), GFP_KERNEL);
4840         if (!isec)
4841                 return -ENOMEM;
4842
4843         sid = task_sid(task);
4844         isec->sclass = sclass;
4845         isec->sid = sid;
4846         perm->security = isec;
4847
4848         return 0;
4849 }
4850
4851 static void ipc_free_security(struct kern_ipc_perm *perm)
4852 {
4853         struct ipc_security_struct *isec = perm->security;
4854         perm->security = NULL;
4855         kfree(isec);
4856 }
4857
4858 static int msg_msg_alloc_security(struct msg_msg *msg)
4859 {
4860         struct msg_security_struct *msec;
4861
4862         msec = kzalloc(sizeof(struct msg_security_struct), GFP_KERNEL);
4863         if (!msec)
4864                 return -ENOMEM;
4865
4866         msec->sid = SECINITSID_UNLABELED;
4867         msg->security = msec;
4868
4869         return 0;
4870 }
4871
4872 static void msg_msg_free_security(struct msg_msg *msg)
4873 {
4874         struct msg_security_struct *msec = msg->security;
4875
4876         msg->security = NULL;
4877         kfree(msec);
4878 }
4879
4880 static int ipc_has_perm(struct kern_ipc_perm *ipc_perms,
4881                         u32 perms)
4882 {
4883         struct ipc_security_struct *isec;
4884         struct avc_audit_data ad;
4885         u32 sid = current_sid();
4886
4887         isec = ipc_perms->security;
4888
4889         AVC_AUDIT_DATA_INIT(&ad, IPC);
4890         ad.u.ipc_id = ipc_perms->key;
4891
4892         return avc_has_perm(sid, isec->sid, isec->sclass, perms, &ad);
4893 }
4894
4895 static int selinux_msg_msg_alloc_security(struct msg_msg *msg)
4896 {
4897         return msg_msg_alloc_security(msg);
4898 }
4899
4900 static void selinux_msg_msg_free_security(struct msg_msg *msg)
4901 {
4902         msg_msg_free_security(msg);
4903 }
4904
4905 /* message queue security operations */
4906 static int selinux_msg_queue_alloc_security(struct msg_queue *msq)
4907 {
4908         struct ipc_security_struct *isec;
4909         struct avc_audit_data ad;
4910         u32 sid = current_sid();
4911         int rc;
4912
4913         rc = ipc_alloc_security(current, &msq->q_perm, SECCLASS_MSGQ);
4914         if (rc)
4915                 return rc;
4916
4917         isec = msq->q_perm.security;
4918
4919         AVC_AUDIT_DATA_INIT(&ad, IPC);
4920         ad.u.ipc_id = msq->q_perm.key;
4921
4922         rc = avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
4923                           MSGQ__CREATE, &ad);
4924         if (rc) {
4925                 ipc_free_security(&msq->q_perm);
4926                 return rc;
4927         }
4928         return 0;
4929 }
4930
4931 static void selinux_msg_queue_free_security(struct msg_queue *msq)
4932 {
4933         ipc_free_security(&msq->q_perm);
4934 }
4935
4936 static int selinux_msg_queue_associate(struct msg_queue *msq, int msqflg)
4937 {
4938         struct ipc_security_struct *isec;
4939         struct avc_audit_data ad;
4940         u32 sid = current_sid();
4941
4942         isec = msq->q_perm.security;
4943
4944         AVC_AUDIT_DATA_INIT(&ad, IPC);
4945         ad.u.ipc_id = msq->q_perm.key;
4946
4947         return avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
4948                             MSGQ__ASSOCIATE, &ad);
4949 }
4950
4951 static int selinux_msg_queue_msgctl(struct msg_queue *msq, int cmd)
4952 {
4953         int err;
4954         int perms;
4955
4956         switch (cmd) {
4957         case IPC_INFO:
4958         case MSG_INFO:
4959                 /* No specific object, just general system-wide information. */
4960                 return task_has_system(current, SYSTEM__IPC_INFO);
4961         case IPC_STAT:
4962         case MSG_STAT:
4963                 perms = MSGQ__GETATTR | MSGQ__ASSOCIATE;
4964                 break;
4965         case IPC_SET:
4966                 perms = MSGQ__SETATTR;
4967                 break;
4968         case IPC_RMID:
4969                 perms = MSGQ__DESTROY;
4970                 break;
4971         default:
4972                 return 0;
4973         }
4974
4975         err = ipc_has_perm(&msq->q_perm, perms);
4976         return err;
4977 }
4978
4979 static int selinux_msg_queue_msgsnd(struct msg_queue *msq, struct msg_msg *msg, int msqflg)
4980 {
4981         struct ipc_security_struct *isec;
4982         struct msg_security_struct *msec;
4983         struct avc_audit_data ad;
4984         u32 sid = current_sid();
4985         int rc;
4986
4987         isec = msq->q_perm.security;
4988         msec = msg->security;
4989
4990         /*
4991          * First time through, need to assign label to the message
4992          */
4993         if (msec->sid == SECINITSID_UNLABELED) {
4994                 /*
4995                  * Compute new sid based on current process and
4996                  * message queue this message will be stored in
4997                  */
4998                 rc = security_transition_sid(sid, isec->sid, SECCLASS_MSG,
4999                                              &msec->sid);
5000                 if (rc)
5001                         return rc;
5002         }
5003
5004         AVC_AUDIT_DATA_INIT(&ad, IPC);
5005         ad.u.ipc_id = msq->q_perm.key;
5006
5007         /* Can this process write to the queue? */
5008         rc = avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
5009                           MSGQ__WRITE, &ad);
5010         if (!rc)
5011                 /* Can this process send the message */
5012                 rc = avc_has_perm(sid, msec->sid, SECCLASS_MSG,
5013                                   MSG__SEND, &ad);
5014         if (!rc)
5015                 /* Can the message be put in the queue? */
5016                 rc = avc_has_perm(msec->sid, isec->sid, SECCLASS_MSGQ,
5017                                   MSGQ__ENQUEUE, &ad);
5018
5019         return rc;
5020 }
5021
5022 static int selinux_msg_queue_msgrcv(struct msg_queue *msq, struct msg_msg *msg,
5023                                     struct task_struct *target,
5024                                     long type, int mode)
5025 {
5026         struct ipc_security_struct *isec;
5027         struct msg_security_struct *msec;
5028         struct avc_audit_data ad;
5029         u32 sid = task_sid(target);
5030         int rc;
5031
5032         isec = msq->q_perm.security;
5033         msec = msg->security;
5034
5035         AVC_AUDIT_DATA_INIT(&ad, IPC);
5036         ad.u.ipc_id = msq->q_perm.key;
5037
5038         rc = avc_has_perm(sid, isec->sid,
5039                           SECCLASS_MSGQ, MSGQ__READ, &ad);
5040         if (!rc)
5041                 rc = avc_has_perm(sid, msec->sid,
5042                                   SECCLASS_MSG, MSG__RECEIVE, &ad);
5043         return rc;
5044 }
5045
5046 /* Shared Memory security operations */
5047 static int selinux_shm_alloc_security(struct shmid_kernel *shp)
5048 {
5049         struct ipc_security_struct *isec;
5050         struct avc_audit_data ad;
5051         u32 sid = current_sid();
5052         int rc;
5053
5054         rc = ipc_alloc_security(current, &shp->shm_perm, SECCLASS_SHM);
5055         if (rc)
5056                 return rc;
5057
5058         isec = shp->shm_perm.security;
5059
5060         AVC_AUDIT_DATA_INIT(&ad, IPC);
5061         ad.u.ipc_id = shp->shm_perm.key;
5062
5063         rc = avc_has_perm(sid, isec->sid, SECCLASS_SHM,
5064                           SHM__CREATE, &ad);
5065         if (rc) {
5066                 ipc_free_security(&shp->shm_perm);
5067                 return rc;
5068         }
5069         return 0;
5070 }
5071
5072 static void selinux_shm_free_security(struct shmid_kernel *shp)
5073 {
5074         ipc_free_security(&shp->shm_perm);
5075 }
5076
5077 static int selinux_shm_associate(struct shmid_kernel *shp, int shmflg)
5078 {
5079         struct ipc_security_struct *isec;
5080         struct avc_audit_data ad;
5081         u32 sid = current_sid();
5082
5083         isec = shp->shm_perm.security;
5084
5085         AVC_AUDIT_DATA_INIT(&ad, IPC);
5086         ad.u.ipc_id = shp->shm_perm.key;
5087
5088         return avc_has_perm(sid, isec->sid, SECCLASS_SHM,
5089                             SHM__ASSOCIATE, &ad);
5090 }
5091
5092 /* Note, at this point, shp is locked down */
5093 static int selinux_shm_shmctl(struct shmid_kernel *shp, int cmd)
5094 {
5095         int perms;
5096         int err;
5097
5098         switch (cmd) {
5099         case IPC_INFO:
5100         case SHM_INFO:
5101                 /* No specific object, just general system-wide information. */
5102                 return task_has_system(current, SYSTEM__IPC_INFO);
5103         case IPC_STAT:
5104         case SHM_STAT:
5105                 perms = SHM__GETATTR | SHM__ASSOCIATE;
5106                 break;
5107         case IPC_SET:
5108                 perms = SHM__SETATTR;
5109                 break;
5110         case SHM_LOCK:
5111         case SHM_UNLOCK:
5112                 perms = SHM__LOCK;
5113                 break;
5114         case IPC_RMID:
5115                 perms = SHM__DESTROY;
5116                 break;
5117         default:
5118                 return 0;
5119         }
5120
5121         err = ipc_has_perm(&shp->shm_perm, perms);
5122         return err;
5123 }
5124
5125 static int selinux_shm_shmat(struct shmid_kernel *shp,
5126                              char __user *shmaddr, int shmflg)
5127 {
5128         u32 perms;
5129         int rc;
5130
5131         rc = secondary_ops->shm_shmat(shp, shmaddr, shmflg);
5132         if (rc)
5133                 return rc;
5134
5135         if (shmflg & SHM_RDONLY)
5136                 perms = SHM__READ;
5137         else
5138                 perms = SHM__READ | SHM__WRITE;
5139
5140         return ipc_has_perm(&shp->shm_perm, perms);
5141 }
5142
5143 /* Semaphore security operations */
5144 static int selinux_sem_alloc_security(struct sem_array *sma)
5145 {
5146         struct ipc_security_struct *isec;
5147         struct avc_audit_data ad;
5148         u32 sid = current_sid();
5149         int rc;
5150
5151         rc = ipc_alloc_security(current, &sma->sem_perm, SECCLASS_SEM);
5152         if (rc)
5153                 return rc;
5154
5155         isec = sma->sem_perm.security;
5156
5157         AVC_AUDIT_DATA_INIT(&ad, IPC);
5158         ad.u.ipc_id = sma->sem_perm.key;
5159
5160         rc = avc_has_perm(sid, isec->sid, SECCLASS_SEM,
5161                           SEM__CREATE, &ad);
5162         if (rc) {
5163                 ipc_free_security(&sma->sem_perm);
5164                 return rc;
5165         }
5166         return 0;
5167 }
5168
5169 static void selinux_sem_free_security(struct sem_array *sma)
5170 {
5171         ipc_free_security(&sma->sem_perm);
5172 }
5173
5174 static int selinux_sem_associate(struct sem_array *sma, int semflg)
5175 {
5176         struct ipc_security_struct *isec;
5177         struct avc_audit_data ad;
5178         u32 sid = current_sid();
5179
5180         isec = sma->sem_perm.security;
5181
5182         AVC_AUDIT_DATA_INIT(&ad, IPC);
5183         ad.u.ipc_id = sma->sem_perm.key;
5184
5185         return avc_has_perm(sid, isec->sid, SECCLASS_SEM,
5186                             SEM__ASSOCIATE, &ad);
5187 }
5188
5189 /* Note, at this point, sma is locked down */
5190 static int selinux_sem_semctl(struct sem_array *sma, int cmd)
5191 {
5192         int err;
5193         u32 perms;
5194
5195         switch (cmd) {
5196         case IPC_INFO:
5197         case SEM_INFO:
5198                 /* No specific object, just general system-wide information. */
5199                 return task_has_system(current, SYSTEM__IPC_INFO);
5200         case GETPID:
5201         case GETNCNT:
5202         case GETZCNT:
5203                 perms = SEM__GETATTR;
5204                 break;
5205         case GETVAL:
5206         case GETALL:
5207                 perms = SEM__READ;
5208                 break;
5209         case SETVAL:
5210         case SETALL:
5211                 perms = SEM__WRITE;
5212                 break;
5213         case IPC_RMID:
5214                 perms = SEM__DESTROY;
5215                 break;
5216         case IPC_SET:
5217                 perms = SEM__SETATTR;
5218                 break;
5219         case IPC_STAT:
5220         case SEM_STAT:
5221                 perms = SEM__GETATTR | SEM__ASSOCIATE;
5222                 break;
5223         default:
5224                 return 0;
5225         }
5226
5227         err = ipc_has_perm(&sma->sem_perm, perms);
5228         return err;
5229 }
5230
5231 static int selinux_sem_semop(struct sem_array *sma,
5232                              struct sembuf *sops, unsigned nsops, int alter)
5233 {
5234         u32 perms;
5235
5236         if (alter)
5237                 perms = SEM__READ | SEM__WRITE;
5238         else
5239                 perms = SEM__READ;
5240
5241         return ipc_has_perm(&sma->sem_perm, perms);
5242 }
5243
5244 static int selinux_ipc_permission(struct kern_ipc_perm *ipcp, short flag)
5245 {
5246         u32 av = 0;
5247
5248         av = 0;
5249         if (flag & S_IRUGO)
5250                 av |= IPC__UNIX_READ;
5251         if (flag & S_IWUGO)
5252                 av |= IPC__UNIX_WRITE;
5253
5254         if (av == 0)
5255                 return 0;
5256
5257         return ipc_has_perm(ipcp, av);
5258 }
5259
5260 static void selinux_ipc_getsecid(struct kern_ipc_perm *ipcp, u32 *secid)
5261 {
5262         struct ipc_security_struct *isec = ipcp->security;
5263         *secid = isec->sid;
5264 }
5265
5266 static void selinux_d_instantiate(struct dentry *dentry, struct inode *inode)
5267 {
5268         if (inode)
5269                 inode_doinit_with_dentry(inode, dentry);
5270 }
5271
5272 static int selinux_getprocattr(struct task_struct *p,
5273                                char *name, char **value)
5274 {
5275         const struct task_security_struct *__tsec;
5276         u32 sid;
5277         int error;
5278         unsigned len;
5279
5280         if (current != p) {
5281                 error = current_has_perm(p, PROCESS__GETATTR);
5282                 if (error)
5283                         return error;
5284         }
5285
5286         rcu_read_lock();
5287         __tsec = __task_cred(p)->security;
5288
5289         if (!strcmp(name, "current"))
5290                 sid = __tsec->sid;
5291         else if (!strcmp(name, "prev"))
5292                 sid = __tsec->osid;
5293         else if (!strcmp(name, "exec"))
5294                 sid = __tsec->exec_sid;
5295         else if (!strcmp(name, "fscreate"))
5296                 sid = __tsec->create_sid;
5297         else if (!strcmp(name, "keycreate"))
5298                 sid = __tsec->keycreate_sid;
5299         else if (!strcmp(name, "sockcreate"))
5300                 sid = __tsec->sockcreate_sid;
5301         else
5302                 goto invalid;
5303         rcu_read_unlock();
5304
5305         if (!sid)
5306                 return 0;
5307
5308         error = security_sid_to_context(sid, value, &len);
5309         if (error)
5310                 return error;
5311         return len;
5312
5313 invalid:
5314         rcu_read_unlock();
5315         return -EINVAL;
5316 }
5317
5318 static int selinux_setprocattr(struct task_struct *p,
5319                                char *name, void *value, size_t size)
5320 {
5321         struct task_security_struct *tsec;
5322         struct task_struct *tracer;
5323         struct cred *new;
5324         u32 sid = 0, ptsid;
5325         int error;
5326         char *str = value;
5327
5328         if (current != p) {
5329                 /* SELinux only allows a process to change its own
5330                    security attributes. */
5331                 return -EACCES;
5332         }
5333
5334         /*
5335          * Basic control over ability to set these attributes at all.
5336          * current == p, but we'll pass them separately in case the
5337          * above restriction is ever removed.
5338          */
5339         if (!strcmp(name, "exec"))
5340                 error = current_has_perm(p, PROCESS__SETEXEC);
5341         else if (!strcmp(name, "fscreate"))
5342                 error = current_has_perm(p, PROCESS__SETFSCREATE);
5343         else if (!strcmp(name, "keycreate"))
5344                 error = current_has_perm(p, PROCESS__SETKEYCREATE);
5345         else if (!strcmp(name, "sockcreate"))
5346                 error = current_has_perm(p, PROCESS__SETSOCKCREATE);
5347         else if (!strcmp(name, "current"))
5348                 error = current_has_perm(p, PROCESS__SETCURRENT);
5349         else
5350                 error = -EINVAL;
5351         if (error)
5352                 return error;
5353
5354         /* Obtain a SID for the context, if one was specified. */
5355         if (size && str[1] && str[1] != '\n') {
5356                 if (str[size-1] == '\n') {
5357                         str[size-1] = 0;
5358                         size--;
5359                 }
5360                 error = security_context_to_sid(value, size, &sid);
5361                 if (error == -EINVAL && !strcmp(name, "fscreate")) {
5362                         if (!capable(CAP_MAC_ADMIN))
5363                                 return error;
5364                         error = security_context_to_sid_force(value, size,
5365                                                               &sid);
5366                 }
5367                 if (error)
5368                         return error;
5369         }
5370
5371         new = prepare_creds();
5372         if (!new)
5373                 return -ENOMEM;
5374
5375         /* Permission checking based on the specified context is
5376            performed during the actual operation (execve,
5377            open/mkdir/...), when we know the full context of the
5378            operation.  See selinux_bprm_set_creds for the execve
5379            checks and may_create for the file creation checks. The
5380            operation will then fail if the context is not permitted. */
5381         tsec = new->security;
5382         if (!strcmp(name, "exec")) {
5383                 tsec->exec_sid = sid;
5384         } else if (!strcmp(name, "fscreate")) {
5385                 tsec->create_sid = sid;
5386         } else if (!strcmp(name, "keycreate")) {
5387                 error = may_create_key(sid, p);
5388                 if (error)
5389                         goto abort_change;
5390                 tsec->keycreate_sid = sid;
5391         } else if (!strcmp(name, "sockcreate")) {
5392                 tsec->sockcreate_sid = sid;
5393         } else if (!strcmp(name, "current")) {
5394                 error = -EINVAL;
5395                 if (sid == 0)
5396                         goto abort_change;
5397
5398                 /* Only allow single threaded processes to change context */
5399                 error = -EPERM;
5400                 if (!is_single_threaded(p)) {
5401                         error = security_bounded_transition(tsec->sid, sid);
5402                         if (error)
5403                                 goto abort_change;
5404                 }
5405
5406                 /* Check permissions for the transition. */
5407                 error = avc_has_perm(tsec->sid, sid, SECCLASS_PROCESS,
5408                                      PROCESS__DYNTRANSITION, NULL);
5409                 if (error)
5410                         goto abort_change;
5411
5412                 /* Check for ptracing, and update the task SID if ok.
5413                    Otherwise, leave SID unchanged and fail. */
5414                 ptsid = 0;
5415                 task_lock(p);
5416                 tracer = tracehook_tracer_task(p);
5417                 if (tracer)
5418                         ptsid = task_sid(tracer);
5419                 task_unlock(p);
5420
5421                 if (tracer) {
5422                         error = avc_has_perm(ptsid, sid, SECCLASS_PROCESS,
5423                                              PROCESS__PTRACE, NULL);
5424                         if (error)
5425                                 goto abort_change;
5426                 }
5427
5428                 tsec->sid = sid;
5429         } else {
5430                 error = -EINVAL;
5431                 goto abort_change;
5432         }
5433
5434         commit_creds(new);
5435         return size;
5436
5437 abort_change:
5438         abort_creds(new);
5439         return error;
5440 }
5441
5442 static int selinux_secid_to_secctx(u32 secid, char **secdata, u32 *seclen)
5443 {
5444         return security_sid_to_context(secid, secdata, seclen);
5445 }
5446
5447 static int selinux_secctx_to_secid(const char *secdata, u32 seclen, u32 *secid)
5448 {
5449         return security_context_to_sid(secdata, seclen, secid);
5450 }
5451
5452 static void selinux_release_secctx(char *secdata, u32 seclen)
5453 {
5454         kfree(secdata);
5455 }
5456
5457 #ifdef CONFIG_KEYS
5458
5459 static int selinux_key_alloc(struct key *k, const struct cred *cred,
5460                              unsigned long flags)
5461 {
5462         const struct task_security_struct *tsec;
5463         struct key_security_struct *ksec;
5464
5465         ksec = kzalloc(sizeof(struct key_security_struct), GFP_KERNEL);
5466         if (!ksec)
5467                 return -ENOMEM;
5468
5469         tsec = cred->security;
5470         if (tsec->keycreate_sid)
5471                 ksec->sid = tsec->keycreate_sid;
5472         else
5473                 ksec->sid = tsec->sid;
5474
5475         k->security = ksec;
5476         return 0;
5477 }
5478
5479 static void selinux_key_free(struct key *k)
5480 {
5481         struct key_security_struct *ksec = k->security;
5482
5483         k->security = NULL;
5484         kfree(ksec);
5485 }
5486
5487 static int selinux_key_permission(key_ref_t key_ref,
5488                                   const struct cred *cred,
5489                                   key_perm_t perm)
5490 {
5491         struct key *key;
5492         struct key_security_struct *ksec;
5493         u32 sid;
5494
5495         /* if no specific permissions are requested, we skip the
5496            permission check. No serious, additional covert channels
5497            appear to be created. */
5498         if (perm == 0)
5499                 return 0;
5500
5501         sid = cred_sid(cred);
5502
5503         key = key_ref_to_ptr(key_ref);
5504         ksec = key->security;
5505
5506         return avc_has_perm(sid, ksec->sid, SECCLASS_KEY, perm, NULL);
5507 }
5508
5509 static int selinux_key_getsecurity(struct key *key, char **_buffer)
5510 {
5511         struct key_security_struct *ksec = key->security;
5512         char *context = NULL;
5513         unsigned len;
5514         int rc;
5515
5516         rc = security_sid_to_context(ksec->sid, &context, &len);
5517         if (!rc)
5518                 rc = len;
5519         *_buffer = context;
5520         return rc;
5521 }
5522
5523 #endif
5524
5525 static struct security_operations selinux_ops = {
5526         .name =                         "selinux",
5527
5528         .ptrace_may_access =            selinux_ptrace_may_access,
5529         .ptrace_traceme =               selinux_ptrace_traceme,
5530         .capget =                       selinux_capget,
5531         .capset =                       selinux_capset,
5532         .sysctl =                       selinux_sysctl,
5533         .capable =                      selinux_capable,
5534         .quotactl =                     selinux_quotactl,
5535         .quota_on =                     selinux_quota_on,
5536         .syslog =                       selinux_syslog,
5537         .vm_enough_memory =             selinux_vm_enough_memory,
5538
5539         .netlink_send =                 selinux_netlink_send,
5540         .netlink_recv =                 selinux_netlink_recv,
5541
5542         .bprm_set_creds =               selinux_bprm_set_creds,
5543         .bprm_committing_creds =        selinux_bprm_committing_creds,
5544         .bprm_committed_creds =         selinux_bprm_committed_creds,
5545         .bprm_secureexec =              selinux_bprm_secureexec,
5546
5547         .sb_alloc_security =            selinux_sb_alloc_security,
5548         .sb_free_security =             selinux_sb_free_security,
5549         .sb_copy_data =                 selinux_sb_copy_data,
5550         .sb_kern_mount =                selinux_sb_kern_mount,
5551         .sb_show_options =              selinux_sb_show_options,
5552         .sb_statfs =                    selinux_sb_statfs,
5553         .sb_mount =                     selinux_mount,
5554         .sb_umount =                    selinux_umount,
5555         .sb_set_mnt_opts =              selinux_set_mnt_opts,
5556         .sb_clone_mnt_opts =            selinux_sb_clone_mnt_opts,
5557         .sb_parse_opts_str =            selinux_parse_opts_str,
5558
5559
5560         .inode_alloc_security =         selinux_inode_alloc_security,
5561         .inode_free_security =          selinux_inode_free_security,
5562         .inode_init_security =          selinux_inode_init_security,
5563         .inode_create =                 selinux_inode_create,
5564         .inode_link =                   selinux_inode_link,
5565         .inode_unlink =                 selinux_inode_unlink,
5566         .inode_symlink =                selinux_inode_symlink,
5567         .inode_mkdir =                  selinux_inode_mkdir,
5568         .inode_rmdir =                  selinux_inode_rmdir,
5569         .inode_mknod =                  selinux_inode_mknod,
5570         .inode_rename =                 selinux_inode_rename,
5571         .inode_readlink =               selinux_inode_readlink,
5572         .inode_follow_link =            selinux_inode_follow_link,
5573         .inode_permission =             selinux_inode_permission,
5574         .inode_setattr =                selinux_inode_setattr,
5575         .inode_getattr =                selinux_inode_getattr,
5576         .inode_setxattr =               selinux_inode_setxattr,
5577         .inode_post_setxattr =          selinux_inode_post_setxattr,
5578         .inode_getxattr =               selinux_inode_getxattr,
5579         .inode_listxattr =              selinux_inode_listxattr,
5580         .inode_removexattr =            selinux_inode_removexattr,
5581         .inode_getsecurity =            selinux_inode_getsecurity,
5582         .inode_setsecurity =            selinux_inode_setsecurity,
5583         .inode_listsecurity =           selinux_inode_listsecurity,
5584         .inode_need_killpriv =          selinux_inode_need_killpriv,
5585         .inode_killpriv =               selinux_inode_killpriv,
5586         .inode_getsecid =               selinux_inode_getsecid,
5587
5588         .file_permission =              selinux_file_permission,
5589         .file_alloc_security =          selinux_file_alloc_security,
5590         .file_free_security =           selinux_file_free_security,
5591         .file_ioctl =                   selinux_file_ioctl,
5592         .file_mmap =                    selinux_file_mmap,
5593         .file_mprotect =                selinux_file_mprotect,
5594         .file_lock =                    selinux_file_lock,
5595         .file_fcntl =                   selinux_file_fcntl,
5596         .file_set_fowner =              selinux_file_set_fowner,
5597         .file_send_sigiotask =          selinux_file_send_sigiotask,
5598         .file_receive =                 selinux_file_receive,
5599
5600         .dentry_open =                  selinux_dentry_open,
5601
5602         .task_create =                  selinux_task_create,
5603         .cred_free =                    selinux_cred_free,
5604         .cred_prepare =                 selinux_cred_prepare,
5605         .kernel_act_as =                selinux_kernel_act_as,
5606         .kernel_create_files_as =       selinux_kernel_create_files_as,
5607         .task_setuid =                  selinux_task_setuid,
5608         .task_fix_setuid =              selinux_task_fix_setuid,
5609         .task_setgid =                  selinux_task_setgid,
5610         .task_setpgid =                 selinux_task_setpgid,
5611         .task_getpgid =                 selinux_task_getpgid,
5612         .task_getsid =                  selinux_task_getsid,
5613         .task_getsecid =                selinux_task_getsecid,
5614         .task_setgroups =               selinux_task_setgroups,
5615         .task_setnice =                 selinux_task_setnice,
5616         .task_setioprio =               selinux_task_setioprio,
5617         .task_getioprio =               selinux_task_getioprio,
5618         .task_setrlimit =               selinux_task_setrlimit,
5619         .task_setscheduler =            selinux_task_setscheduler,
5620         .task_getscheduler =            selinux_task_getscheduler,
5621         .task_movememory =              selinux_task_movememory,
5622         .task_kill =                    selinux_task_kill,
5623         .task_wait =                    selinux_task_wait,
5624         .task_prctl =                   selinux_task_prctl,
5625         .task_to_inode =                selinux_task_to_inode,
5626
5627         .ipc_permission =               selinux_ipc_permission,
5628         .ipc_getsecid =                 selinux_ipc_getsecid,
5629
5630         .msg_msg_alloc_security =       selinux_msg_msg_alloc_security,
5631         .msg_msg_free_security =        selinux_msg_msg_free_security,
5632
5633         .msg_queue_alloc_security =     selinux_msg_queue_alloc_security,
5634         .msg_queue_free_security =      selinux_msg_queue_free_security,
5635         .msg_queue_associate =          selinux_msg_queue_associate,
5636         .msg_queue_msgctl =             selinux_msg_queue_msgctl,
5637         .msg_queue_msgsnd =             selinux_msg_queue_msgsnd,
5638         .msg_queue_msgrcv =             selinux_msg_queue_msgrcv,
5639
5640         .shm_alloc_security =           selinux_shm_alloc_security,
5641         .shm_free_security =            selinux_shm_free_security,
5642         .shm_associate =                selinux_shm_associate,
5643         .shm_shmctl =                   selinux_shm_shmctl,
5644         .shm_shmat =                    selinux_shm_shmat,
5645
5646         .sem_alloc_security =           selinux_sem_alloc_security,
5647         .sem_free_security =            selinux_sem_free_security,
5648         .sem_associate =                selinux_sem_associate,
5649         .sem_semctl =                   selinux_sem_semctl,
5650         .sem_semop =                    selinux_sem_semop,
5651
5652         .d_instantiate =                selinux_d_instantiate,
5653
5654         .getprocattr =                  selinux_getprocattr,
5655         .setprocattr =                  selinux_setprocattr,
5656
5657         .secid_to_secctx =              selinux_secid_to_secctx,
5658         .secctx_to_secid =              selinux_secctx_to_secid,
5659         .release_secctx =               selinux_release_secctx,
5660
5661         .unix_stream_connect =          selinux_socket_unix_stream_connect,
5662         .unix_may_send =                selinux_socket_unix_may_send,
5663
5664         .socket_create =                selinux_socket_create,
5665         .socket_post_create =           selinux_socket_post_create,
5666         .socket_bind =                  selinux_socket_bind,
5667         .socket_connect =               selinux_socket_connect,
5668         .socket_listen =                selinux_socket_listen,
5669         .socket_accept =                selinux_socket_accept,
5670         .socket_sendmsg =               selinux_socket_sendmsg,
5671         .socket_recvmsg =               selinux_socket_recvmsg,
5672         .socket_getsockname =           selinux_socket_getsockname,
5673         .socket_getpeername =           selinux_socket_getpeername,
5674         .socket_getsockopt =            selinux_socket_getsockopt,
5675         .socket_setsockopt =            selinux_socket_setsockopt,
5676         .socket_shutdown =              selinux_socket_shutdown,
5677         .socket_sock_rcv_skb =          selinux_socket_sock_rcv_skb,
5678         .socket_getpeersec_stream =     selinux_socket_getpeersec_stream,
5679         .socket_getpeersec_dgram =      selinux_socket_getpeersec_dgram,
5680         .sk_alloc_security =            selinux_sk_alloc_security,
5681         .sk_free_security =             selinux_sk_free_security,
5682         .sk_clone_security =            selinux_sk_clone_security,
5683         .sk_getsecid =                  selinux_sk_getsecid,
5684         .sock_graft =                   selinux_sock_graft,
5685         .inet_conn_request =            selinux_inet_conn_request,
5686         .inet_csk_clone =               selinux_inet_csk_clone,
5687         .inet_conn_established =        selinux_inet_conn_established,
5688         .req_classify_flow =            selinux_req_classify_flow,
5689
5690 #ifdef CONFIG_SECURITY_NETWORK_XFRM
5691         .xfrm_policy_alloc_security =   selinux_xfrm_policy_alloc,
5692         .xfrm_policy_clone_security =   selinux_xfrm_policy_clone,
5693         .xfrm_policy_free_security =    selinux_xfrm_policy_free,
5694         .xfrm_policy_delete_security =  selinux_xfrm_policy_delete,
5695         .xfrm_state_alloc_security =    selinux_xfrm_state_alloc,
5696         .xfrm_state_free_security =     selinux_xfrm_state_free,
5697         .xfrm_state_delete_security =   selinux_xfrm_state_delete,
5698         .xfrm_policy_lookup =           selinux_xfrm_policy_lookup,
5699         .xfrm_state_pol_flow_match =    selinux_xfrm_state_pol_flow_match,
5700         .xfrm_decode_session =          selinux_xfrm_decode_session,
5701 #endif
5702
5703 #ifdef CONFIG_KEYS
5704         .key_alloc =                    selinux_key_alloc,
5705         .key_free =                     selinux_key_free,
5706         .key_permission =               selinux_key_permission,
5707         .key_getsecurity =              selinux_key_getsecurity,
5708 #endif
5709
5710 #ifdef CONFIG_AUDIT
5711         .audit_rule_init =              selinux_audit_rule_init,
5712         .audit_rule_known =             selinux_audit_rule_known,
5713         .audit_rule_match =             selinux_audit_rule_match,
5714         .audit_rule_free =              selinux_audit_rule_free,
5715 #endif
5716 };
5717
5718 static __init int selinux_init(void)
5719 {
5720         if (!security_module_enable(&selinux_ops)) {
5721                 selinux_enabled = 0;
5722                 return 0;
5723         }
5724
5725         if (!selinux_enabled) {
5726                 printk(KERN_INFO "SELinux:  Disabled at boot.\n");
5727                 return 0;
5728         }
5729
5730         printk(KERN_INFO "SELinux:  Initializing.\n");
5731
5732         /* Set the security state for the initial task. */
5733         cred_init_security();
5734
5735         sel_inode_cache = kmem_cache_create("selinux_inode_security",
5736                                             sizeof(struct inode_security_struct),
5737                                             0, SLAB_PANIC, NULL);
5738         avc_init();
5739
5740         secondary_ops = security_ops;
5741         if (!secondary_ops)
5742                 panic("SELinux: No initial security operations\n");
5743         if (register_security(&selinux_ops))
5744                 panic("SELinux: Unable to register with kernel.\n");
5745
5746         if (selinux_enforcing)
5747                 printk(KERN_DEBUG "SELinux:  Starting in enforcing mode\n");
5748         else
5749                 printk(KERN_DEBUG "SELinux:  Starting in permissive mode\n");
5750
5751         return 0;
5752 }
5753
5754 void selinux_complete_init(void)
5755 {
5756         printk(KERN_DEBUG "SELinux:  Completing initialization.\n");
5757
5758         /* Set up any superblocks initialized prior to the policy load. */
5759         printk(KERN_DEBUG "SELinux:  Setting up existing superblocks.\n");
5760         spin_lock(&sb_lock);
5761         spin_lock(&sb_security_lock);
5762 next_sb:
5763         if (!list_empty(&superblock_security_head)) {
5764                 struct superblock_security_struct *sbsec =
5765                                 list_entry(superblock_security_head.next,
5766                                            struct superblock_security_struct,
5767                                            list);
5768                 struct super_block *sb = sbsec->sb;
5769                 sb->s_count++;
5770                 spin_unlock(&sb_security_lock);
5771                 spin_unlock(&sb_lock);
5772                 down_read(&sb->s_umount);
5773                 if (sb->s_root)
5774                         superblock_doinit(sb, NULL);
5775                 drop_super(sb);
5776                 spin_lock(&sb_lock);
5777                 spin_lock(&sb_security_lock);
5778                 list_del_init(&sbsec->list);
5779                 goto next_sb;
5780         }
5781         spin_unlock(&sb_security_lock);
5782         spin_unlock(&sb_lock);
5783 }
5784
5785 /* SELinux requires early initialization in order to label
5786    all processes and objects when they are created. */
5787 security_initcall(selinux_init);
5788
5789 #if defined(CONFIG_NETFILTER)
5790
5791 static struct nf_hook_ops selinux_ipv4_ops[] = {
5792         {
5793                 .hook =         selinux_ipv4_postroute,
5794                 .owner =        THIS_MODULE,
5795                 .pf =           PF_INET,
5796                 .hooknum =      NF_INET_POST_ROUTING,
5797                 .priority =     NF_IP_PRI_SELINUX_LAST,
5798         },
5799         {
5800                 .hook =         selinux_ipv4_forward,
5801                 .owner =        THIS_MODULE,
5802                 .pf =           PF_INET,
5803                 .hooknum =      NF_INET_FORWARD,
5804                 .priority =     NF_IP_PRI_SELINUX_FIRST,
5805         },
5806         {
5807                 .hook =         selinux_ipv4_output,
5808                 .owner =        THIS_MODULE,
5809                 .pf =           PF_INET,
5810                 .hooknum =      NF_INET_LOCAL_OUT,
5811                 .priority =     NF_IP_PRI_SELINUX_FIRST,
5812         }
5813 };
5814
5815 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
5816
5817 static struct nf_hook_ops selinux_ipv6_ops[] = {
5818         {
5819                 .hook =         selinux_ipv6_postroute,
5820                 .owner =        THIS_MODULE,
5821                 .pf =           PF_INET6,
5822                 .hooknum =      NF_INET_POST_ROUTING,
5823                 .priority =     NF_IP6_PRI_SELINUX_LAST,
5824         },
5825         {
5826                 .hook =         selinux_ipv6_forward,
5827                 .owner =        THIS_MODULE,
5828                 .pf =           PF_INET6,
5829                 .hooknum =      NF_INET_FORWARD,
5830                 .priority =     NF_IP6_PRI_SELINUX_FIRST,
5831         }
5832 };
5833
5834 #endif  /* IPV6 */
5835
5836 static int __init selinux_nf_ip_init(void)
5837 {
5838         int err = 0;
5839
5840         if (!selinux_enabled)
5841                 goto out;
5842
5843         printk(KERN_DEBUG "SELinux:  Registering netfilter hooks\n");
5844
5845         err = nf_register_hooks(selinux_ipv4_ops, ARRAY_SIZE(selinux_ipv4_ops));
5846         if (err)
5847                 panic("SELinux: nf_register_hooks for IPv4: error %d\n", err);
5848
5849 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
5850         err = nf_register_hooks(selinux_ipv6_ops, ARRAY_SIZE(selinux_ipv6_ops));
5851         if (err)
5852                 panic("SELinux: nf_register_hooks for IPv6: error %d\n", err);
5853 #endif  /* IPV6 */
5854
5855 out:
5856         return err;
5857 }
5858
5859 __initcall(selinux_nf_ip_init);
5860
5861 #ifdef CONFIG_SECURITY_SELINUX_DISABLE
5862 static void selinux_nf_ip_exit(void)
5863 {
5864         printk(KERN_DEBUG "SELinux:  Unregistering netfilter hooks\n");
5865
5866         nf_unregister_hooks(selinux_ipv4_ops, ARRAY_SIZE(selinux_ipv4_ops));
5867 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
5868         nf_unregister_hooks(selinux_ipv6_ops, ARRAY_SIZE(selinux_ipv6_ops));
5869 #endif  /* IPV6 */
5870 }
5871 #endif
5872
5873 #else /* CONFIG_NETFILTER */
5874
5875 #ifdef CONFIG_SECURITY_SELINUX_DISABLE
5876 #define selinux_nf_ip_exit()
5877 #endif
5878
5879 #endif /* CONFIG_NETFILTER */
5880
5881 #ifdef CONFIG_SECURITY_SELINUX_DISABLE
5882 static int selinux_disabled;
5883
5884 int selinux_disable(void)
5885 {
5886         extern void exit_sel_fs(void);
5887
5888         if (ss_initialized) {
5889                 /* Not permitted after initial policy load. */
5890                 return -EINVAL;
5891         }
5892
5893         if (selinux_disabled) {
5894                 /* Only do this once. */
5895                 return -EINVAL;
5896         }
5897
5898         printk(KERN_INFO "SELinux:  Disabled at runtime.\n");
5899
5900         selinux_disabled = 1;
5901         selinux_enabled = 0;
5902
5903         /* Reset security_ops to the secondary module, dummy or capability. */
5904         security_ops = secondary_ops;
5905
5906         /* Unregister netfilter hooks. */
5907         selinux_nf_ip_exit();
5908
5909         /* Unregister selinuxfs. */
5910         exit_sel_fs();
5911
5912         return 0;
5913 }
5914 #endif