kernel/security/selinux/hooks.c

   1 /*
   2  *  NSA Security-Enhanced Linux (SELinux) security module
   3  *
   4  *  This file contains the SELinux hook function implementations.
   5  *
   6  *  Authors:  Stephen Smalley, <sds@epoch.ncsc.mil>
   7  *            Chris Vance, <cvance@nai.com>
   8  *            Wayne Salamon, <wsalamon@nai.com>
   9  *            James Morris <jmorris@redhat.com>
  10  *
  11  *  Copyright (C) 2001,2002 Networks Associates Technology, Inc.
  12  *  Copyright (C) 2003-2008 Red Hat, Inc., James Morris <jmorris@redhat.com>
  13  *                                         Eric Paris <eparis@redhat.com>
  14  *  Copyright (C) 2004-2005 Trusted Computer Solutions, Inc.
  15  *                          <dgoeddel@trustedcs.com>
  16  *  Copyright (C) 2006, 2007, 2009 Hewlett-Packard Development Company, L.P.
  17  *      Paul Moore <paul@paul-moore.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/kd.h>
  28 #include <linux/kernel.h>
  29 #include <linux/tracehook.h>
  30 #include <linux/errno.h>
  31 #include <linux/sched.h>
  32 #include <linux/security.h>
  33 #include <linux/xattr.h>
  34 #include <linux/capability.h>
  35 #include <linux/unistd.h>
  36 #include <linux/mm.h>
  37 #include <linux/mman.h>
  38 #include <linux/slab.h>
  39 #include <linux/pagemap.h>
  40 #include <linux/proc_fs.h>
  41 #include <linux/swap.h>
  42 #include <linux/spinlock.h>
  43 #include <linux/syscalls.h>
  44 #include <linux/dcache.h>
  45 #include <linux/file.h>
  46 #include <linux/fdtable.h>
  47 #include <linux/namei.h>
  48 #include <linux/mount.h>
  49 #include <linux/netfilter_ipv4.h>
  50 #include <linux/netfilter_ipv6.h>
  51 #include <linux/tty.h>
  52 #include <net/icmp.h>
  53 #include <net/ip.h>             /* for local_port_range[] */
  54 #include <net/tcp.h>            /* struct or_callable used in sock_rcv_skb */
  55 #include <net/inet_connection_sock.h>
  56 #include <net/net_namespace.h>
  57 #include <net/netlabel.h>
  58 #include <linux/uaccess.h>
  59 #include <asm/ioctls.h>
  60 #include <linux/atomic.h>
  61 #include <linux/bitops.h>
  62 #include <linux/interrupt.h>
  63 #include <linux/netdevice.h>    /* for network interface checks */
  64 #include <net/netlink.h>
  65 #include <linux/tcp.h>
  66 #include <linux/udp.h>
  67 #include <linux/dccp.h>
  68 #include <linux/quota.h>
  69 #include <linux/un.h>           /* for Unix socket types */
  70 #include <net/af_unix.h>        /* for Unix socket types */
  71 #include <linux/parser.h>
  72 #include <linux/nfs_mount.h>
  73 #include <net/ipv6.h>
  74 #include <linux/hugetlb.h>
  75 #include <linux/personality.h>
  76 #include <linux/audit.h>
  77 #include <linux/string.h>
  78 #include <linux/selinux.h>
  79 #include <linux/mutex.h>
  80 #include <linux/posix-timers.h>
  81 #include <linux/syslog.h>
  82 #include <linux/user_namespace.h>
  83 #include <linux/export.h>
  84 #include <linux/msg.h>
  85 #include <linux/shm.h>
  86
  87 #include "avc.h"
  88 #include "objsec.h"
  89 #include "netif.h"
  90 #include "netnode.h"
  91 #include "netport.h"
  92 #include "xfrm.h"
  93 #include "netlabel.h"
  94 #include "audit.h"
  95 #include "avc_ss.h"
  96
  97 /* SECMARK reference count */
  98 static atomic_t selinux_secmark_refcount = ATOMIC_INIT(0);
  99
 100 #ifdef CONFIG_SECURITY_SELINUX_DEVELOP
 101 int selinux_enforcing;
 102
 103 static int __init enforcing_setup(char *str)
 104 {
 105         unsigned long enforcing;
 106         if (!kstrtoul(str, 0, &enforcing))
 107                 selinux_enforcing = enforcing ? 1 : 0;
 108         return 1;
 109 }
 110 __setup("enforcing=", enforcing_setup);
 111 #endif
 112
 113 #ifdef CONFIG_SECURITY_SELINUX_BOOTPARAM
 114 int selinux_enabled = CONFIG_SECURITY_SELINUX_BOOTPARAM_VALUE;
 115
 116 static int __init selinux_enabled_setup(char *str)
 117 {
 118         unsigned long enabled;
 119         if (!kstrtoul(str, 0, &enabled))
 120                 selinux_enabled = enabled ? 1 : 0;
 121         return 1;
 122 }
 123 __setup("selinux=", selinux_enabled_setup);
 124 #else
 125 int selinux_enabled = 1;
 126 #endif
 127
 128 static struct kmem_cache *sel_inode_cache;
 129
 130 /**
 131  * selinux_secmark_enabled - Check to see if SECMARK is currently enabled
 132  *
 133  * Description:
 134  * This function checks the SECMARK reference counter to see if any SECMARK
 135  * targets are currently configured, if the reference counter is greater than
 136  * zero SECMARK is considered to be enabled.  Returns true (1) if SECMARK is
 137  * enabled, false (0) if SECMARK is disabled.  If the always_check_network
 138  * policy capability is enabled, SECMARK is always considered enabled.
 139  *
 140  */
 141 static int selinux_secmark_enabled(void)
 142 {
 143         return (selinux_policycap_alwaysnetwork || atomic_read(&selinux_secmark_refcount));
 144 }
 145
 146 /**
 147  * selinux_peerlbl_enabled - Check to see if peer labeling is currently enabled
 148  *
 149  * Description:
 150  * This function checks if NetLabel or labeled IPSEC is enabled.  Returns true
 151  * (1) if any are enabled or false (0) if neither are enabled.  If the
 152  * always_check_network policy capability is enabled, peer labeling
 153  * is always considered enabled.
 154  *
 155  */
 156 static int selinux_peerlbl_enabled(void)
 157 {
 158         return (selinux_policycap_alwaysnetwork || netlbl_enabled() || selinux_xfrm_enabled());
 159 }
 160
 161 static int selinux_netcache_avc_callback(u32 event)
 162 {
 163         if (event == AVC_CALLBACK_RESET) {
 164                 sel_netif_flush();
 165                 sel_netnode_flush();
 166                 sel_netport_flush();
 167                 synchronize_net();
 168         }
 169         return 0;
 170 }
 171
 172 /*
 173  * initialise the security for the init task
 174  */
 175 static void cred_init_security(void)
 176 {
 177         struct cred *cred = (struct cred *) current->real_cred;
 178         struct task_security_struct *tsec;
 179
 180         tsec = kzalloc(sizeof(struct task_security_struct), GFP_KERNEL);
 181         if (!tsec)
 182                 panic("SELinux:  Failed to initialize initial task.\n");
 183
 184         tsec->osid = tsec->sid = SECINITSID_KERNEL;
 185         cred->security = tsec;
 186 }
 187
 188 /*
 189  * get the security ID of a set of credentials
 190  */
 191 static inline u32 cred_sid(const struct cred *cred)
 192 {
 193         const struct task_security_struct *tsec;
 194
 195         tsec = cred->security;
 196         return tsec->sid;
 197 }
 198
 199 /*
 200  * get the objective security ID of a task
 201  */
 202 static inline u32 task_sid(const struct task_struct *task)
 203 {
 204         u32 sid;
 205
 206         rcu_read_lock();
 207         sid = cred_sid(__task_cred(task));
 208         rcu_read_unlock();
 209         return sid;
 210 }
 211
 212 /*
 213  * get the subjective security ID of the current task
 214  */
 215 static inline u32 current_sid(void)
 216 {
 217         const struct task_security_struct *tsec = current_security();
 218
 219         return tsec->sid;
 220 }
 221
 222 /* Allocate and free functions for each kind of security blob. */
 223
 224 static int inode_alloc_security(struct inode *inode)
 225 {
 226         struct inode_security_struct *isec;
 227         u32 sid = current_sid();
 228
 229         isec = kmem_cache_zalloc(sel_inode_cache, GFP_NOFS);
 230         if (!isec)
 231                 return -ENOMEM;
 232
 233         mutex_init(&isec->lock);
 234         INIT_LIST_HEAD(&isec->list);
 235         isec->inode = inode;
 236         isec->sid = SECINITSID_UNLABELED;
 237         isec->sclass = SECCLASS_FILE;
 238         isec->task_sid = sid;
 239         inode->i_security = isec;
 240
 241         return 0;
 242 }
 243
 244 static void inode_free_rcu(struct rcu_head *head)
 245 {
 246         struct inode_security_struct *isec;
 247
 248         isec = container_of(head, struct inode_security_struct, rcu);
 249         kmem_cache_free(sel_inode_cache, isec);
 250 }
 251
 252 static void inode_free_security(struct inode *inode)
 253 {
 254         struct inode_security_struct *isec = inode->i_security;
 255         struct superblock_security_struct *sbsec = inode->i_sb->s_security;
 256
 257         spin_lock(&sbsec->isec_lock);
 258         if (!list_empty(&isec->list))
 259                 list_del_init(&isec->list);
 260         spin_unlock(&sbsec->isec_lock);
 261
 262         /*
 263          * The inode may still be referenced in a path walk and
 264          * a call to selinux_inode_permission() can be made
 265          * after inode_free_security() is called. Ideally, the VFS
 266          * wouldn't do this, but fixing that is a much harder
 267          * job. For now, simply free the i_security via RCU, and
 268          * leave the current inode->i_security pointer intact.
 269          * The inode will be freed after the RCU grace period too.
 270          */
 271         call_rcu(&isec->rcu, inode_free_rcu);
 272 }
 273
 274 static int file_alloc_security(struct file *file)
 275 {
 276         struct file_security_struct *fsec;
 277         u32 sid = current_sid();
 278
 279         fsec = kzalloc(sizeof(struct file_security_struct), GFP_KERNEL);
 280         if (!fsec)
 281                 return -ENOMEM;
 282
 283         fsec->sid = sid;
 284         fsec->fown_sid = sid;
 285         file->f_security = fsec;
 286
 287         return 0;
 288 }
 289
 290 static void file_free_security(struct file *file)
 291 {
 292         struct file_security_struct *fsec = file->f_security;
 293         file->f_security = NULL;
 294         kfree(fsec);
 295 }
 296
 297 static int superblock_alloc_security(struct super_block *sb)
 298 {
 299         struct superblock_security_struct *sbsec;
 300
 301         sbsec = kzalloc(sizeof(struct superblock_security_struct), GFP_KERNEL);
 302         if (!sbsec)
 303                 return -ENOMEM;
 304
 305         mutex_init(&sbsec->lock);
 306         INIT_LIST_HEAD(&sbsec->isec_head);
 307         spin_lock_init(&sbsec->isec_lock);
 308         sbsec->sb = sb;
 309         sbsec->sid = SECINITSID_UNLABELED;
 310         sbsec->def_sid = SECINITSID_FILE;
 311         sbsec->mntpoint_sid = SECINITSID_UNLABELED;
 312         sb->s_security = sbsec;
 313
 314         return 0;
 315 }
 316
 317 static void superblock_free_security(struct super_block *sb)
 318 {
 319         struct superblock_security_struct *sbsec = sb->s_security;
 320         sb->s_security = NULL;
 321         kfree(sbsec);
 322 }
 323
 324 /* The file system's label must be initialized prior to use. */
 325
 326 static const char *labeling_behaviors[7] = {
 327         "uses xattr",
 328         "uses transition SIDs",
 329         "uses task SIDs",
 330         "uses genfs_contexts",
 331         "not configured for labeling",
 332         "uses mountpoint labeling",
 333         "uses native labeling",
 334 };
 335
 336 static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dentry);
 337
 338 static inline int inode_doinit(struct inode *inode)
 339 {
 340         return inode_doinit_with_dentry(inode, NULL);
 341 }
 342
 343 enum {
 344         Opt_error = -1,
 345         Opt_context = 1,
 346         Opt_fscontext = 2,
 347         Opt_defcontext = 3,
 348         Opt_rootcontext = 4,
 349         Opt_labelsupport = 5,
 350         Opt_nextmntopt = 6,
 351 };
 352
 353 #define NUM_SEL_MNT_OPTS        (Opt_nextmntopt - 1)
 354
 355 static const match_table_t tokens = {
 356         {Opt_context, CONTEXT_STR "%s"},
 357         {Opt_fscontext, FSCONTEXT_STR "%s"},
 358         {Opt_defcontext, DEFCONTEXT_STR "%s"},
 359         {Opt_rootcontext, ROOTCONTEXT_STR "%s"},
 360         {Opt_labelsupport, LABELSUPP_STR},
 361         {Opt_error, NULL},
 362 };
 363
 364 #define SEL_MOUNT_FAIL_MSG "SELinux:  duplicate or incompatible mount options\n"
 365
 366 static int may_context_mount_sb_relabel(u32 sid,
 367                         struct superblock_security_struct *sbsec,
 368                         const struct cred *cred)
 369 {
 370         const struct task_security_struct *tsec = cred->security;
 371         int rc;
 372
 373         rc = avc_has_perm(tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM,
 374                           FILESYSTEM__RELABELFROM, NULL);
 375         if (rc)
 376                 return rc;
 377
 378         rc = avc_has_perm(tsec->sid, sid, SECCLASS_FILESYSTEM,
 379                           FILESYSTEM__RELABELTO, NULL);
 380         return rc;
 381 }
 382
 383 static int may_context_mount_inode_relabel(u32 sid,
 384                         struct superblock_security_struct *sbsec,
 385                         const struct cred *cred)
 386 {
 387         const struct task_security_struct *tsec = cred->security;
 388         int rc;
 389         rc = avc_has_perm(tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM,
 390                           FILESYSTEM__RELABELFROM, NULL);
 391         if (rc)
 392                 return rc;
 393
 394         rc = avc_has_perm(sid, sbsec->sid, SECCLASS_FILESYSTEM,
 395                           FILESYSTEM__ASSOCIATE, NULL);
 396         return rc;
 397 }
 398
 399 static int selinux_is_sblabel_mnt(struct super_block *sb)
 400 {
 401         struct superblock_security_struct *sbsec = sb->s_security;
 402
 403         return sbsec->behavior == SECURITY_FS_USE_XATTR ||
 404                 sbsec->behavior == SECURITY_FS_USE_TRANS ||
 405                 sbsec->behavior == SECURITY_FS_USE_TASK ||
 406                 sbsec->behavior == SECURITY_FS_USE_NATIVE ||
 407                 /* Special handling. Genfs but also in-core setxattr handler */
 408                 !strcmp(sb->s_type->name, "sysfs") ||
 409                 !strcmp(sb->s_type->name, "pstore") ||
 410                 !strcmp(sb->s_type->name, "debugfs") ||
 411                 !strcmp(sb->s_type->name, "rootfs");
 412 }
 413
 414 static int sb_finish_set_opts(struct super_block *sb)
 415 {
 416         struct superblock_security_struct *sbsec = sb->s_security;
 417         struct dentry *root = sb->s_root;
 418         struct inode *root_inode = d_backing_inode(root);
 419         int rc = 0;
 420
 421         if (sbsec->behavior == SECURITY_FS_USE_XATTR) {
 422                 /* Make sure that the xattr handler exists and that no
 423                    error other than -ENODATA is returned by getxattr on
 424                    the root directory.  -ENODATA is ok, as this may be
 425                    the first boot of the SELinux kernel before we have
 426                    assigned xattr values to the filesystem. */
 427                 if (!root_inode->i_op->getxattr) {
 428                         printk(KERN_WARNING "SELinux: (dev %s, type %s) has no "
 429                                "xattr support\n", sb->s_id, sb->s_type->name);
 430                         rc = -EOPNOTSUPP;
 431                         goto out;
 432                 }
 433                 rc = root_inode->i_op->getxattr(root, XATTR_NAME_SELINUX, NULL, 0);
 434                 if (rc < 0 && rc != -ENODATA) {
 435                         if (rc == -EOPNOTSUPP)
 436                                 printk(KERN_WARNING "SELinux: (dev %s, type "
 437                                        "%s) has no security xattr handler\n",
 438                                        sb->s_id, sb->s_type->name);
 439                         else
 440                                 printk(KERN_WARNING "SELinux: (dev %s, type "
 441                                        "%s) getxattr errno %d\n", sb->s_id,
 442                                        sb->s_type->name, -rc);
 443                         goto out;
 444                 }
 445         }
 446
 447         if (sbsec->behavior > ARRAY_SIZE(labeling_behaviors))
 448                 printk(KERN_ERR "SELinux: initialized (dev %s, type %s), unknown behavior\n",
 449                        sb->s_id, sb->s_type->name);
 450
 451         sbsec->flags |= SE_SBINITIALIZED;
 452         if (selinux_is_sblabel_mnt(sb))
 453                 sbsec->flags |= SBLABEL_MNT;
 454
 455         /* Initialize the root inode. */
 456         rc = inode_doinit_with_dentry(root_inode, root);
 457
 458         /* Initialize any other inodes associated with the superblock, e.g.
 459            inodes created prior to initial policy load or inodes created
 460            during get_sb by a pseudo filesystem that directly
 461            populates itself. */
 462         spin_lock(&sbsec->isec_lock);
 463 next_inode:
 464         if (!list_empty(&sbsec->isec_head)) {
 465                 struct inode_security_struct *isec =
 466                                 list_entry(sbsec->isec_head.next,
 467                                            struct inode_security_struct, list);
 468                 struct inode *inode = isec->inode;
 469                 list_del_init(&isec->list);
 470                 spin_unlock(&sbsec->isec_lock);
 471                 inode = igrab(inode);
 472                 if (inode) {
 473                         if (!IS_PRIVATE(inode))
 474                                 inode_doinit(inode);
 475                         iput(inode);
 476                 }
 477                 spin_lock(&sbsec->isec_lock);
 478                 goto next_inode;
 479         }
 480         spin_unlock(&sbsec->isec_lock);
 481 out:
 482         return rc;
 483 }
 484
 485 /*
 486  * This function should allow an FS to ask what it's mount security
 487  * options were so it can use those later for submounts, displaying
 488  * mount options, or whatever.
 489  */
 490 static int selinux_get_mnt_opts(const struct super_block *sb,
 491                                 struct security_mnt_opts *opts)
 492 {
 493         int rc = 0, i;
 494         struct superblock_security_struct *sbsec = sb->s_security;
 495         char *context = NULL;
 496         u32 len;
 497         char tmp;
 498
 499         security_init_mnt_opts(opts);
 500
 501         if (!(sbsec->flags & SE_SBINITIALIZED))
 502                 return -EINVAL;
 503
 504         if (!ss_initialized)
 505                 return -EINVAL;
 506
 507         /* make sure we always check enough bits to cover the mask */
 508         BUILD_BUG_ON(SE_MNTMASK >= (1 << NUM_SEL_MNT_OPTS));
 509
 510         tmp = sbsec->flags & SE_MNTMASK;
 511         /* count the number of mount options for this sb */
 512         for (i = 0; i < NUM_SEL_MNT_OPTS; i++) {
 513                 if (tmp & 0x01)
 514                         opts->num_mnt_opts++;
 515                 tmp >>= 1;
 516         }
 517         /* Check if the Label support flag is set */
 518         if (sbsec->flags & SBLABEL_MNT)
 519                 opts->num_mnt_opts++;
 520
 521         opts->mnt_opts = kcalloc(opts->num_mnt_opts, sizeof(char *), GFP_ATOMIC);
 522         if (!opts->mnt_opts) {
 523                 rc = -ENOMEM;
 524                 goto out_free;
 525         }
 526
 527         opts->mnt_opts_flags = kcalloc(opts->num_mnt_opts, sizeof(int), GFP_ATOMIC);
 528         if (!opts->mnt_opts_flags) {
 529                 rc = -ENOMEM;
 530                 goto out_free;
 531         }
 532
 533         i = 0;
 534         if (sbsec->flags & FSCONTEXT_MNT) {
 535                 rc = security_sid_to_context(sbsec->sid, &context, &len);
 536                 if (rc)
 537                         goto out_free;
 538                 opts->mnt_opts[i] = context;
 539                 opts->mnt_opts_flags[i++] = FSCONTEXT_MNT;
 540         }
 541         if (sbsec->flags & CONTEXT_MNT) {
 542                 rc = security_sid_to_context(sbsec->mntpoint_sid, &context, &len);
 543                 if (rc)
 544                         goto out_free;
 545                 opts->mnt_opts[i] = context;
 546                 opts->mnt_opts_flags[i++] = CONTEXT_MNT;
 547         }
 548         if (sbsec->flags & DEFCONTEXT_MNT) {
 549                 rc = security_sid_to_context(sbsec->def_sid, &context, &len);
 550                 if (rc)
 551                         goto out_free;
 552                 opts->mnt_opts[i] = context;
 553                 opts->mnt_opts_flags[i++] = DEFCONTEXT_MNT;
 554         }
 555         if (sbsec->flags & ROOTCONTEXT_MNT) {
 556                 struct inode *root = d_backing_inode(sbsec->sb->s_root);
 557                 struct inode_security_struct *isec = root->i_security;
 558
 559                 rc = security_sid_to_context(isec->sid, &context, &len);
 560                 if (rc)
 561                         goto out_free;
 562                 opts->mnt_opts[i] = context;
 563                 opts->mnt_opts_flags[i++] = ROOTCONTEXT_MNT;
 564         }
 565         if (sbsec->flags & SBLABEL_MNT) {
 566                 opts->mnt_opts[i] = NULL;
 567                 opts->mnt_opts_flags[i++] = SBLABEL_MNT;
 568         }
 569
 570         BUG_ON(i != opts->num_mnt_opts);
 571
 572         return 0;
 573
 574 out_free:
 575         security_free_mnt_opts(opts);
 576         return rc;
 577 }
 578
 579 static int bad_option(struct superblock_security_struct *sbsec, char flag,
 580                       u32 old_sid, u32 new_sid)
 581 {
 582         char mnt_flags = sbsec->flags & SE_MNTMASK;
 583
 584         /* check if the old mount command had the same options */
 585         if (sbsec->flags & SE_SBINITIALIZED)
 586                 if (!(sbsec->flags & flag) ||
 587                     (old_sid != new_sid))
 588                         return 1;
 589
 590         /* check if we were passed the same options twice,
 591          * aka someone passed context=a,context=b
 592          */
 593         if (!(sbsec->flags & SE_SBINITIALIZED))
 594                 if (mnt_flags & flag)
 595                         return 1;
 596         return 0;
 597 }
 598
 599 /*
 600  * Allow filesystems with binary mount data to explicitly set mount point
 601  * labeling information.
 602  */
 603 static int selinux_set_mnt_opts(struct super_block *sb,
 604                                 struct security_mnt_opts *opts,
 605                                 unsigned long kern_flags,
 606                                 unsigned long *set_kern_flags)
 607 {
 608         const struct cred *cred = current_cred();
 609         int rc = 0, i;
 610         struct superblock_security_struct *sbsec = sb->s_security;
 611         const char *name = sb->s_type->name;
 612         struct inode *inode = d_backing_inode(sbsec->sb->s_root);
 613         struct inode_security_struct *root_isec = inode->i_security;
 614         u32 fscontext_sid = 0, context_sid = 0, rootcontext_sid = 0;
 615         u32 defcontext_sid = 0;
 616         char **mount_options = opts->mnt_opts;
 617         int *flags = opts->mnt_opts_flags;
 618         int num_opts = opts->num_mnt_opts;
 619
 620         mutex_lock(&sbsec->lock);
 621
 622         if (!ss_initialized) {
 623                 if (!num_opts) {
 624                         /* Defer initialization until selinux_complete_init,
 625                            after the initial policy is loaded and the security
 626                            server is ready to handle calls. */
 627                         goto out;
 628                 }
 629                 rc = -EINVAL;
 630                 printk(KERN_WARNING "SELinux: Unable to set superblock options "
 631                         "before the security server is initialized\n");
 632                 goto out;
 633         }
 634         if (kern_flags && !set_kern_flags) {
 635                 /* Specifying internal flags without providing a place to
 636                  * place the results is not allowed */
 637                 rc = -EINVAL;
 638                 goto out;
 639         }
 640
 641         /*
 642          * Binary mount data FS will come through this function twice.  Once
 643          * from an explicit call and once from the generic calls from the vfs.
 644          * Since the generic VFS calls will not contain any security mount data
 645          * we need to skip the double mount verification.
 646          *
 647          * This does open a hole in which we will not notice if the first
 648          * mount using this sb set explict options and a second mount using
 649          * this sb does not set any security options.  (The first options
 650          * will be used for both mounts)
 651          */
 652         if ((sbsec->flags & SE_SBINITIALIZED) && (sb->s_type->fs_flags & FS_BINARY_MOUNTDATA)
 653             && (num_opts == 0))
 654                 goto out;
 655
 656         /*
 657          * parse the mount options, check if they are valid sids.
 658          * also check if someone is trying to mount the same sb more
 659          * than once with different security options.
 660          */
 661         for (i = 0; i < num_opts; i++) {
 662                 u32 sid;
 663
 664                 if (flags[i] == SBLABEL_MNT)
 665                         continue;
 666                 rc = security_context_to_sid(mount_options[i],
 667                                              strlen(mount_options[i]), &sid, GFP_KERNEL);
 668                 if (rc) {
 669                         printk(KERN_WARNING "SELinux: security_context_to_sid"
 670                                "(%s) failed for (dev %s, type %s) errno=%d\n",
 671                                mount_options[i], sb->s_id, name, rc);
 672                         goto out;
 673                 }
 674                 switch (flags[i]) {
 675                 case FSCONTEXT_MNT:
 676                         fscontext_sid = sid;
 677
 678                         if (bad_option(sbsec, FSCONTEXT_MNT, sbsec->sid,
 679                                         fscontext_sid))
 680                                 goto out_double_mount;
 681
 682                         sbsec->flags |= FSCONTEXT_MNT;
 683                         break;
 684                 case CONTEXT_MNT:
 685                         context_sid = sid;
 686
 687                         if (bad_option(sbsec, CONTEXT_MNT, sbsec->mntpoint_sid,
 688                                         context_sid))
 689                                 goto out_double_mount;
 690
 691                         sbsec->flags |= CONTEXT_MNT;
 692                         break;
 693                 case ROOTCONTEXT_MNT:
 694                         rootcontext_sid = sid;
 695
 696                         if (bad_option(sbsec, ROOTCONTEXT_MNT, root_isec->sid,
 697                                         rootcontext_sid))
 698                                 goto out_double_mount;
 699
 700                         sbsec->flags |= ROOTCONTEXT_MNT;
 701
 702                         break;
 703                 case DEFCONTEXT_MNT:
 704                         defcontext_sid = sid;
 705
 706                         if (bad_option(sbsec, DEFCONTEXT_MNT, sbsec->def_sid,
 707                                         defcontext_sid))
 708                                 goto out_double_mount;
 709
 710                         sbsec->flags |= DEFCONTEXT_MNT;
 711
 712                         break;
 713                 default:
 714                         rc = -EINVAL;
 715                         goto out;
 716                 }
 717         }
 718
 719         if (sbsec->flags & SE_SBINITIALIZED) {
 720                 /* previously mounted with options, but not on this attempt? */
 721                 if ((sbsec->flags & SE_MNTMASK) && !num_opts)
 722                         goto out_double_mount;
 723                 rc = 0;
 724                 goto out;
 725         }
 726
 727         if (strcmp(sb->s_type->name, "proc") == 0)
 728                 sbsec->flags |= SE_SBPROC;
 729
 730         if (!sbsec->behavior) {
 731                 /*
 732                  * Determine the labeling behavior to use for this
 733                  * filesystem type.
 734                  */
 735                 rc = security_fs_use(sb);
 736                 if (rc) {
 737                         printk(KERN_WARNING
 738                                 "%s: security_fs_use(%s) returned %d\n",
 739                                         __func__, sb->s_type->name, rc);
 740                         goto out;
 741                 }
 742         }
 743         /* sets the context of the superblock for the fs being mounted. */
 744         if (fscontext_sid) {
 745                 rc = may_context_mount_sb_relabel(fscontext_sid, sbsec, cred);
 746                 if (rc)
 747                         goto out;
 748
 749                 sbsec->sid = fscontext_sid;
 750         }
 751
 752         /*
 753          * Switch to using mount point labeling behavior.
 754          * sets the label used on all file below the mountpoint, and will set
 755          * the superblock context if not already set.
 756          */
 757         if (kern_flags & SECURITY_LSM_NATIVE_LABELS && !context_sid) {
 758                 sbsec->behavior = SECURITY_FS_USE_NATIVE;
 759                 *set_kern_flags |= SECURITY_LSM_NATIVE_LABELS;
 760         }
 761
 762         if (context_sid) {
 763                 if (!fscontext_sid) {
 764                         rc = may_context_mount_sb_relabel(context_sid, sbsec,
 765                                                           cred);
 766                         if (rc)
 767                                 goto out;
 768                         sbsec->sid = context_sid;
 769                 } else {
 770                         rc = may_context_mount_inode_relabel(context_sid, sbsec,
 771                                                              cred);
 772                         if (rc)
 773                                 goto out;
 774                 }
 775                 if (!rootcontext_sid)
 776                         rootcontext_sid = context_sid;
 777
 778                 sbsec->mntpoint_sid = context_sid;
 779                 sbsec->behavior = SECURITY_FS_USE_MNTPOINT;
 780         }
 781
 782         if (rootcontext_sid) {
 783                 rc = may_context_mount_inode_relabel(rootcontext_sid, sbsec,
 784                                                      cred);
 785                 if (rc)
 786                         goto out;
 787
 788                 root_isec->sid = rootcontext_sid;
 789                 root_isec->initialized = 1;
 790         }
 791
 792         if (defcontext_sid) {
 793                 if (sbsec->behavior != SECURITY_FS_USE_XATTR &&
 794                         sbsec->behavior != SECURITY_FS_USE_NATIVE) {
 795                         rc = -EINVAL;
 796                         printk(KERN_WARNING "SELinux: defcontext option is "
 797                                "invalid for this filesystem type\n");
 798                         goto out;
 799                 }
 800
 801                 if (defcontext_sid != sbsec->def_sid) {
 802                         rc = may_context_mount_inode_relabel(defcontext_sid,
 803                                                              sbsec, cred);
 804                         if (rc)
 805                                 goto out;
 806                 }
 807
 808                 sbsec->def_sid = defcontext_sid;
 809         }
 810
 811         rc = sb_finish_set_opts(sb);
 812 out:
 813         mutex_unlock(&sbsec->lock);
 814         return rc;
 815 out_double_mount:
 816         rc = -EINVAL;
 817         printk(KERN_WARNING "SELinux: mount invalid.  Same superblock, different "
 818                "security settings for (dev %s, type %s)\n", sb->s_id, name);
 819         goto out;
 820 }
 821
 822 static int selinux_cmp_sb_context(const struct super_block *oldsb,
 823                                     const struct super_block *newsb)
 824 {
 825         struct superblock_security_struct *old = oldsb->s_security;
 826         struct superblock_security_struct *new = newsb->s_security;
 827         char oldflags = old->flags & SE_MNTMASK;
 828         char newflags = new->flags & SE_MNTMASK;
 829
 830         if (oldflags != newflags)
 831                 goto mismatch;
 832         if ((oldflags & FSCONTEXT_MNT) && old->sid != new->sid)
 833                 goto mismatch;
 834         if ((oldflags & CONTEXT_MNT) && old->mntpoint_sid != new->mntpoint_sid)
 835                 goto mismatch;
 836         if ((oldflags & DEFCONTEXT_MNT) && old->def_sid != new->def_sid)
 837                 goto mismatch;
 838         if (oldflags & ROOTCONTEXT_MNT) {
 839                 struct inode_security_struct *oldroot = d_backing_inode(oldsb->s_root)->i_security;
 840                 struct inode_security_struct *newroot = d_backing_inode(newsb->s_root)->i_security;
 841                 if (oldroot->sid != newroot->sid)
 842                         goto mismatch;
 843         }
 844         return 0;
 845 mismatch:
 846         printk(KERN_WARNING "SELinux: mount invalid.  Same superblock, "
 847                             "different security settings for (dev %s, "
 848                             "type %s)\n", newsb->s_id, newsb->s_type->name);
 849         return -EBUSY;
 850 }
 851
 852 static int selinux_sb_clone_mnt_opts(const struct super_block *oldsb,
 853                                         struct super_block *newsb)
 854 {
 855         const struct superblock_security_struct *oldsbsec = oldsb->s_security;
 856         struct superblock_security_struct *newsbsec = newsb->s_security;
 857
 858         int set_fscontext =     (oldsbsec->flags & FSCONTEXT_MNT);
 859         int set_context =       (oldsbsec->flags & CONTEXT_MNT);
 860         int set_rootcontext =   (oldsbsec->flags & ROOTCONTEXT_MNT);
 861
 862         /*
 863          * if the parent was able to be mounted it clearly had no special lsm
 864          * mount options.  thus we can safely deal with this superblock later
 865          */
 866         if (!ss_initialized)
 867                 return 0;
 868
 869         /* how can we clone if the old one wasn't set up?? */
 870         BUG_ON(!(oldsbsec->flags & SE_SBINITIALIZED));
 871
 872         /* if fs is reusing a sb, make sure that the contexts match */
 873         if (newsbsec->flags & SE_SBINITIALIZED)
 874                 return selinux_cmp_sb_context(oldsb, newsb);
 875
 876         mutex_lock(&newsbsec->lock);
 877
 878         newsbsec->flags = oldsbsec->flags;
 879
 880         newsbsec->sid = oldsbsec->sid;
 881         newsbsec->def_sid = oldsbsec->def_sid;
 882         newsbsec->behavior = oldsbsec->behavior;
 883
 884         if (set_context) {
 885                 u32 sid = oldsbsec->mntpoint_sid;
 886
 887                 if (!set_fscontext)
 888                         newsbsec->sid = sid;
 889                 if (!set_rootcontext) {
 890                         struct inode *newinode = d_backing_inode(newsb->s_root);
 891                         struct inode_security_struct *newisec = newinode->i_security;
 892                         newisec->sid = sid;
 893                 }
 894                 newsbsec->mntpoint_sid = sid;
 895         }
 896         if (set_rootcontext) {
 897                 const struct inode *oldinode = d_backing_inode(oldsb->s_root);
 898                 const struct inode_security_struct *oldisec = oldinode->i_security;
 899                 struct inode *newinode = d_backing_inode(newsb->s_root);
 900                 struct inode_security_struct *newisec = newinode->i_security;
 901
 902                 newisec->sid = oldisec->sid;
 903         }
 904
 905         sb_finish_set_opts(newsb);
 906         mutex_unlock(&newsbsec->lock);
 907         return 0;
 908 }
 909
 910 static int selinux_parse_opts_str(char *options,
 911                                   struct security_mnt_opts *opts)
 912 {
 913         char *p;
 914         char *context = NULL, *defcontext = NULL;
 915         char *fscontext = NULL, *rootcontext = NULL;
 916         int rc, num_mnt_opts = 0;
 917
 918         opts->num_mnt_opts = 0;
 919
 920         /* Standard string-based options. */
 921         while ((p = strsep(&options, "|")) != NULL) {
 922                 int token;
 923                 substring_t args[MAX_OPT_ARGS];
 924
 925                 if (!*p)
 926                         continue;
 927
 928                 token = match_token(p, tokens, args);
 929
 930                 switch (token) {
 931                 case Opt_context:
 932                         if (context || defcontext) {
 933                                 rc = -EINVAL;
 934                                 printk(KERN_WARNING SEL_MOUNT_FAIL_MSG);
 935                                 goto out_err;
 936                         }
 937                         context = match_strdup(&args[0]);
 938                         if (!context) {
 939                                 rc = -ENOMEM;
 940                                 goto out_err;
 941                         }
 942                         break;
 943
 944                 case Opt_fscontext:
 945                         if (fscontext) {
 946                                 rc = -EINVAL;
 947                                 printk(KERN_WARNING SEL_MOUNT_FAIL_MSG);
 948                                 goto out_err;
 949                         }
 950                         fscontext = match_strdup(&args[0]);
 951                         if (!fscontext) {
 952                                 rc = -ENOMEM;
 953                                 goto out_err;
 954                         }
 955                         break;
 956
 957                 case Opt_rootcontext:
 958                         if (rootcontext) {
 959                                 rc = -EINVAL;
 960                                 printk(KERN_WARNING SEL_MOUNT_FAIL_MSG);
 961                                 goto out_err;
 962                         }
 963                         rootcontext = match_strdup(&args[0]);
 964                         if (!rootcontext) {
 965                                 rc = -ENOMEM;
 966                                 goto out_err;
 967                         }
 968                         break;
 969
 970                 case Opt_defcontext:
 971                         if (context || defcontext) {
 972                                 rc = -EINVAL;
 973                                 printk(KERN_WARNING SEL_MOUNT_FAIL_MSG);
 974                                 goto out_err;
 975                         }
 976                         defcontext = match_strdup(&args[0]);
 977                         if (!defcontext) {
 978                                 rc = -ENOMEM;
 979                                 goto out_err;
 980                         }
 981                         break;
 982                 case Opt_labelsupport:
 983                         break;
 984                 default:
 985                         rc = -EINVAL;
 986                         printk(KERN_WARNING "SELinux:  unknown mount option\n");
 987                         goto out_err;
 988
 989                 }
 990         }
 991
 992         rc = -ENOMEM;
 993         opts->mnt_opts = kcalloc(NUM_SEL_MNT_OPTS, sizeof(char *), GFP_ATOMIC);
 994         if (!opts->mnt_opts)
 995                 goto out_err;
 996
 997         opts->mnt_opts_flags = kcalloc(NUM_SEL_MNT_OPTS, sizeof(int), GFP_ATOMIC);
 998         if (!opts->mnt_opts_flags) {
 999                 kfree(opts->mnt_opts);
1000                 goto out_err;
1001         }
1002
1003         if (fscontext) {
1004                 opts->mnt_opts[num_mnt_opts] = fscontext;
1005                 opts->mnt_opts_flags[num_mnt_opts++] = FSCONTEXT_MNT;
1006         }
1007         if (context) {
1008                 opts->mnt_opts[num_mnt_opts] = context;
1009                 opts->mnt_opts_flags[num_mnt_opts++] = CONTEXT_MNT;
1010         }
1011         if (rootcontext) {
1012                 opts->mnt_opts[num_mnt_opts] = rootcontext;
1013                 opts->mnt_opts_flags[num_mnt_opts++] = ROOTCONTEXT_MNT;
1014         }
1015         if (defcontext) {
1016                 opts->mnt_opts[num_mnt_opts] = defcontext;
1017                 opts->mnt_opts_flags[num_mnt_opts++] = DEFCONTEXT_MNT;
1018         }
1019
1020         opts->num_mnt_opts = num_mnt_opts;
1021         return 0;
1022
1023 out_err:
1024         kfree(context);
1025         kfree(defcontext);
1026         kfree(fscontext);
1027         kfree(rootcontext);
1028         return rc;
1029 }
1030 /*
1031  * string mount options parsing and call set the sbsec
1032  */
1033 static int superblock_doinit(struct super_block *sb, void *data)
1034 {
1035         int rc = 0;
1036         char *options = data;
1037         struct security_mnt_opts opts;
1038
1039         security_init_mnt_opts(&opts);
1040
1041         if (!data)
1042                 goto out;
1043
1044         BUG_ON(sb->s_type->fs_flags & FS_BINARY_MOUNTDATA);
1045
1046         rc = selinux_parse_opts_str(options, &opts);
1047         if (rc)
1048                 goto out_err;
1049
1050 out:
1051         rc = selinux_set_mnt_opts(sb, &opts, 0, NULL);
1052
1053 out_err:
1054         security_free_mnt_opts(&opts);
1055         return rc;
1056 }
1057
1058 static void selinux_write_opts(struct seq_file *m,
1059                                struct security_mnt_opts *opts)
1060 {
1061         int i;
1062         char *prefix;
1063
1064         for (i = 0; i < opts->num_mnt_opts; i++) {
1065                 char *has_comma;
1066
1067                 if (opts->mnt_opts[i])
1068                         has_comma = strchr(opts->mnt_opts[i], ',');
1069                 else
1070                         has_comma = NULL;
1071
1072                 switch (opts->mnt_opts_flags[i]) {
1073                 case CONTEXT_MNT:
1074                         prefix = CONTEXT_STR;
1075                         break;
1076                 case FSCONTEXT_MNT:
1077                         prefix = FSCONTEXT_STR;
1078                         break;
1079                 case ROOTCONTEXT_MNT:
1080                         prefix = ROOTCONTEXT_STR;
1081                         break;
1082                 case DEFCONTEXT_MNT:
1083                         prefix = DEFCONTEXT_STR;
1084                         break;
1085                 case SBLABEL_MNT:
1086                         seq_putc(m, ',');
1087                         seq_puts(m, LABELSUPP_STR);
1088                         continue;
1089                 default:
1090                         BUG();
1091                         return;
1092                 };
1093                 /* we need a comma before each option */
1094                 seq_putc(m, ',');
1095                 seq_puts(m, prefix);
1096                 if (has_comma)
1097                         seq_putc(m, '\"');
1098                 seq_puts(m, opts->mnt_opts[i]);
1099                 if (has_comma)
1100                         seq_putc(m, '\"');
1101         }
1102 }
1103
1104 static int selinux_sb_show_options(struct seq_file *m, struct super_block *sb)
1105 {
1106         struct security_mnt_opts opts;
1107         int rc;
1108
1109         rc = selinux_get_mnt_opts(sb, &opts);
1110         if (rc) {
1111                 /* before policy load we may get EINVAL, don't show anything */
1112                 if (rc == -EINVAL)
1113                         rc = 0;
1114                 return rc;
1115         }
1116
1117         selinux_write_opts(m, &opts);
1118
1119         security_free_mnt_opts(&opts);
1120
1121         return rc;
1122 }
1123
1124 static inline u16 inode_mode_to_security_class(umode_t mode)
1125 {
1126         switch (mode & S_IFMT) {
1127         case S_IFSOCK:
1128                 return SECCLASS_SOCK_FILE;
1129         case S_IFLNK:
1130                 return SECCLASS_LNK_FILE;
1131         case S_IFREG:
1132                 return SECCLASS_FILE;
1133         case S_IFBLK:
1134                 return SECCLASS_BLK_FILE;
1135         case S_IFDIR:
1136                 return SECCLASS_DIR;
1137         case S_IFCHR:
1138                 return SECCLASS_CHR_FILE;
1139         case S_IFIFO:
1140                 return SECCLASS_FIFO_FILE;
1141
1142         }
1143
1144         return SECCLASS_FILE;
1145 }
1146
1147 static inline int default_protocol_stream(int protocol)
1148 {
1149         return (protocol == IPPROTO_IP || protocol == IPPROTO_TCP);
1150 }
1151
1152 static inline int default_protocol_dgram(int protocol)
1153 {
1154         return (protocol == IPPROTO_IP || protocol == IPPROTO_UDP);
1155 }
1156
1157 static inline u16 socket_type_to_security_class(int family, int type, int protocol)
1158 {
1159         switch (family) {
1160         case PF_UNIX:
1161                 switch (type) {
1162                 case SOCK_STREAM:
1163                 case SOCK_SEQPACKET:
1164                         return SECCLASS_UNIX_STREAM_SOCKET;
1165                 case SOCK_DGRAM:
1166                         return SECCLASS_UNIX_DGRAM_SOCKET;
1167                 }
1168                 break;
1169         case PF_INET:
1170         case PF_INET6:
1171                 switch (type) {
1172                 case SOCK_STREAM:
1173                         if (default_protocol_stream(protocol))
1174                                 return SECCLASS_TCP_SOCKET;
1175                         else
1176                                 return SECCLASS_RAWIP_SOCKET;
1177                 case SOCK_DGRAM:
1178                         if (default_protocol_dgram(protocol))
1179                                 return SECCLASS_UDP_SOCKET;
1180                         else
1181                                 return SECCLASS_RAWIP_SOCKET;
1182                 case SOCK_DCCP:
1183                         return SECCLASS_DCCP_SOCKET;
1184                 default:
1185                         return SECCLASS_RAWIP_SOCKET;
1186                 }
1187                 break;
1188         case PF_NETLINK:
1189                 switch (protocol) {
1190                 case NETLINK_ROUTE:
1191                         return SECCLASS_NETLINK_ROUTE_SOCKET;
1192                 case NETLINK_FIREWALL:
1193                         return SECCLASS_NETLINK_FIREWALL_SOCKET;
1194                 case NETLINK_SOCK_DIAG:
1195                         return SECCLASS_NETLINK_TCPDIAG_SOCKET;
1196                 case NETLINK_NFLOG:
1197                         return SECCLASS_NETLINK_NFLOG_SOCKET;
1198                 case NETLINK_XFRM:
1199                         return SECCLASS_NETLINK_XFRM_SOCKET;
1200                 case NETLINK_SELINUX:
1201                         return SECCLASS_NETLINK_SELINUX_SOCKET;
1202                 case NETLINK_AUDIT:
1203                         return SECCLASS_NETLINK_AUDIT_SOCKET;
1204                 case NETLINK_IP6_FW:
1205                         return SECCLASS_NETLINK_IP6FW_SOCKET;
1206                 case NETLINK_DNRTMSG:
1207                         return SECCLASS_NETLINK_DNRT_SOCKET;
1208                 case NETLINK_KOBJECT_UEVENT:
1209                         return SECCLASS_NETLINK_KOBJECT_UEVENT_SOCKET;
1210                 default:
1211                         return SECCLASS_NETLINK_SOCKET;
1212                 }
1213         case PF_PACKET:
1214                 return SECCLASS_PACKET_SOCKET;
1215         case PF_KEY:
1216                 return SECCLASS_KEY_SOCKET;
1217         case PF_APPLETALK:
1218                 return SECCLASS_APPLETALK_SOCKET;
1219         }
1220
1221         return SECCLASS_SOCKET;
1222 }
1223
1224 #ifdef CONFIG_PROC_FS
1225 static int selinux_proc_get_sid(struct dentry *dentry,
1226                                 u16 tclass,
1227                                 u32 *sid)
1228 {
1229         int rc;
1230         char *buffer, *path;
1231
1232         buffer = (char *)__get_free_page(GFP_KERNEL);
1233         if (!buffer)
1234                 return -ENOMEM;
1235
1236         path = dentry_path_raw(dentry, buffer, PAGE_SIZE);
1237         if (IS_ERR(path))
1238                 rc = PTR_ERR(path);
1239         else {
1240                 /* each process gets a /proc/PID/ entry. Strip off the
1241                  * PID part to get a valid selinux labeling.
1242                  * e.g. /proc/1/net/rpc/nfs -> /net/rpc/nfs */
1243                 while (path[1] >= '0' && path[1] <= '9') {
1244                         path[1] = '/';
1245                         path++;
1246                 }
1247                 rc = security_genfs_sid("proc", path, tclass, sid);
1248         }
1249         free_page((unsigned long)buffer);
1250         return rc;
1251 }
1252 #else
1253 static int selinux_proc_get_sid(struct dentry *dentry,
1254                                 u16 tclass,
1255                                 u32 *sid)
1256 {
1257         return -EINVAL;
1258 }
1259 #endif
1260
1261 /* The inode's security attributes must be initialized before first use. */
1262 static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dentry)
1263 {
1264         struct superblock_security_struct *sbsec = NULL;
1265         struct inode_security_struct *isec = inode->i_security;
1266         u32 sid;
1267         struct dentry *dentry;
1268 #define INITCONTEXTLEN 255
1269         char *context = NULL;
1270         unsigned len = 0;
1271         int rc = 0;
1272
1273         if (isec->initialized)
1274                 goto out;
1275
1276         mutex_lock(&isec->lock);
1277         if (isec->initialized)
1278                 goto out_unlock;
1279
1280         sbsec = inode->i_sb->s_security;
1281         if (!(sbsec->flags & SE_SBINITIALIZED)) {
1282                 /* Defer initialization until selinux_complete_init,
1283                    after the initial policy is loaded and the security
1284                    server is ready to handle calls. */
1285                 spin_lock(&sbsec->isec_lock);
1286                 if (list_empty(&isec->list))
1287                         list_add(&isec->list, &sbsec->isec_head);
1288                 spin_unlock(&sbsec->isec_lock);
1289                 goto out_unlock;
1290         }
1291
1292         switch (sbsec->behavior) {
1293         case SECURITY_FS_USE_NATIVE:
1294                 break;
1295         case SECURITY_FS_USE_XATTR:
1296                 if (!inode->i_op->getxattr) {
1297                         isec->sid = sbsec->def_sid;
1298                         break;
1299                 }
1300
1301                 /* Need a dentry, since the xattr API requires one.
1302                    Life would be simpler if we could just pass the inode. */
1303                 if (opt_dentry) {
1304                         /* Called from d_instantiate or d_splice_alias. */
1305                         dentry = dget(opt_dentry);
1306                 } else {
1307                         /* Called from selinux_complete_init, try to find a dentry. */
1308                         dentry = d_find_alias(inode);
1309                 }
1310                 if (!dentry) {
1311                         /*
1312                          * this is can be hit on boot when a file is accessed
1313                          * before the policy is loaded.  When we load policy we
1314                          * may find inodes that have no dentry on the
1315                          * sbsec->isec_head list.  No reason to complain as these
1316                          * will get fixed up the next time we go through
1317                          * inode_doinit with a dentry, before these inodes could
1318                          * be used again by userspace.
1319                          */
1320                         goto out_unlock;
1321                 }
1322
1323                 len = INITCONTEXTLEN;
1324                 context = kmalloc(len+1, GFP_NOFS);
1325                 if (!context) {
1326                         rc = -ENOMEM;
1327                         dput(dentry);
1328                         goto out_unlock;
1329                 }
1330                 context[len] = '\0';
1331                 rc = inode->i_op->getxattr(dentry, XATTR_NAME_SELINUX,
1332                                            context, len);
1333                 if (rc == -ERANGE) {
1334                         kfree(context);
1335
1336                         /* Need a larger buffer.  Query for the right size. */
1337                         rc = inode->i_op->getxattr(dentry, XATTR_NAME_SELINUX,
1338                                                    NULL, 0);
1339                         if (rc < 0) {
1340                                 dput(dentry);
1341                                 goto out_unlock;
1342                         }
1343                         len = rc;
1344                         context = kmalloc(len+1, GFP_NOFS);
1345                         if (!context) {
1346                                 rc = -ENOMEM;
1347                                 dput(dentry);
1348                                 goto out_unlock;
1349                         }
1350                         context[len] = '\0';
1351                         rc = inode->i_op->getxattr(dentry,
1352                                                    XATTR_NAME_SELINUX,
1353                                                    context, len);
1354                 }
1355                 dput(dentry);
1356                 if (rc < 0) {
1357                         if (rc != -ENODATA) {
1358                                 printk(KERN_WARNING "SELinux: %s:  getxattr returned "
1359                                        "%d for dev=%s ino=%ld\n", __func__,
1360                                        -rc, inode->i_sb->s_id, inode->i_ino);
1361                                 kfree(context);
1362                                 goto out_unlock;
1363                         }
1364                         /* Map ENODATA to the default file SID */
1365                         sid = sbsec->def_sid;
1366                         rc = 0;
1367                 } else {
1368                         rc = security_context_to_sid_default(context, rc, &sid,
1369                                                              sbsec->def_sid,
1370                                                              GFP_NOFS);
1371                         if (rc) {
1372                                 char *dev = inode->i_sb->s_id;
1373                                 unsigned long ino = inode->i_ino;
1374
1375                                 if (rc == -EINVAL) {
1376                                         if (printk_ratelimit())
1377                                                 printk(KERN_NOTICE "SELinux: inode=%lu on dev=%s was found to have an invalid "
1378                                                         "context=%s.  This indicates you may need to relabel the inode or the "
1379                                                         "filesystem in question.\n", ino, dev, context);
1380                                 } else {
1381                                         printk(KERN_WARNING "SELinux: %s:  context_to_sid(%s) "
1382                                                "returned %d for dev=%s ino=%ld\n",
1383                                                __func__, context, -rc, dev, ino);
1384                                 }
1385                                 kfree(context);
1386                                 /* Leave with the unlabeled SID */
1387                                 rc = 0;
1388                                 break;
1389                         }
1390                 }
1391                 kfree(context);
1392                 isec->sid = sid;
1393                 break;
1394         case SECURITY_FS_USE_TASK:
1395                 isec->sid = isec->task_sid;
1396                 break;
1397         case SECURITY_FS_USE_TRANS:
1398                 /* Default to the fs SID. */
1399                 isec->sid = sbsec->sid;
1400
1401                 /* Try to obtain a transition SID. */
1402                 isec->sclass = inode_mode_to_security_class(inode->i_mode);
1403                 rc = security_transition_sid(isec->task_sid, sbsec->sid,
1404                                              isec->sclass, NULL, &sid);
1405                 if (rc)
1406                         goto out_unlock;
1407                 isec->sid = sid;
1408                 break;
1409         case SECURITY_FS_USE_MNTPOINT:
1410                 isec->sid = sbsec->mntpoint_sid;
1411                 break;
1412         default:
1413                 /* Default to the fs superblock SID. */
1414                 isec->sid = sbsec->sid;
1415
1416                 if ((sbsec->flags & SE_SBPROC) && !S_ISLNK(inode->i_mode)) {
1417                         /* We must have a dentry to determine the label on
1418                          * procfs inodes */
1419                         if (opt_dentry)
1420                                 /* Called from d_instantiate or
1421                                  * d_splice_alias. */
1422                                 dentry = dget(opt_dentry);
1423                         else
1424                                 /* Called from selinux_complete_init, try to
1425                                  * find a dentry. */
1426                                 dentry = d_find_alias(inode);
1427                         /*
1428                          * This can be hit on boot when a file is accessed
1429                          * before the policy is loaded.  When we load policy we
1430                          * may find inodes that have no dentry on the
1431                          * sbsec->isec_head list.  No reason to complain as
1432                          * these will get fixed up the next time we go through
1433                          * inode_doinit() with a dentry, before these inodes
1434                          * could be used again by userspace.
1435                          */
1436                         if (!dentry)
1437                                 goto out_unlock;
1438                         isec->sclass = inode_mode_to_security_class(inode->i_mode);
1439                         rc = selinux_proc_get_sid(dentry, isec->sclass, &sid);
1440                         dput(dentry);
1441                         if (rc)
1442                                 goto out_unlock;
1443                         isec->sid = sid;
1444                 }
1445                 break;
1446         }
1447
1448         isec->initialized = 1;
1449
1450 out_unlock:
1451         mutex_unlock(&isec->lock);
1452 out:
1453         if (isec->sclass == SECCLASS_FILE)
1454                 isec->sclass = inode_mode_to_security_class(inode->i_mode);
1455         return rc;
1456 }
1457
1458 /* Convert a Linux signal to an access vector. */
1459 static inline u32 signal_to_av(int sig)
1460 {
1461         u32 perm = 0;
1462
1463         switch (sig) {
1464         case SIGCHLD:
1465                 /* Commonly granted from child to parent. */
1466                 perm = PROCESS__SIGCHLD;
1467                 break;
1468         case SIGKILL:
1469                 /* Cannot be caught or ignored */
1470                 perm = PROCESS__SIGKILL;
1471                 break;
1472         case SIGSTOP:
1473                 /* Cannot be caught or ignored */
1474                 perm = PROCESS__SIGSTOP;
1475                 break;
1476         default:
1477                 /* All other signals. */
1478                 perm = PROCESS__SIGNAL;
1479                 break;
1480         }
1481
1482         return perm;
1483 }
1484
1485 /*
1486  * Check permission between a pair of credentials
1487  * fork check, ptrace check, etc.
1488  */
1489 static int cred_has_perm(const struct cred *actor,
1490                          const struct cred *target,
1491                          u32 perms)
1492 {
1493         u32 asid = cred_sid(actor), tsid = cred_sid(target);
1494
1495         return avc_has_perm(asid, tsid, SECCLASS_PROCESS, perms, NULL);
1496 }
1497
1498 /*
1499  * Check permission between a pair of tasks, e.g. signal checks,
1500  * fork check, ptrace check, etc.
1501  * tsk1 is the actor and tsk2 is the target
1502  * - this uses the default subjective creds of tsk1
1503  */
1504 static int task_has_perm(const struct task_struct *tsk1,
1505                          const struct task_struct *tsk2,
1506                          u32 perms)
1507 {
1508         const struct task_security_struct *__tsec1, *__tsec2;
1509         u32 sid1, sid2;
1510
1511         rcu_read_lock();
1512         __tsec1 = __task_cred(tsk1)->security;  sid1 = __tsec1->sid;
1513         __tsec2 = __task_cred(tsk2)->security;  sid2 = __tsec2->sid;
1514         rcu_read_unlock();
1515         return avc_has_perm(sid1, sid2, SECCLASS_PROCESS, perms, NULL);
1516 }
1517
1518 /*
1519  * Check permission between current and another task, e.g. signal checks,
1520  * fork check, ptrace check, etc.
1521  * current is the actor and tsk2 is the target
1522  * - this uses current's subjective creds
1523  */
1524 static int current_has_perm(const struct task_struct *tsk,
1525                             u32 perms)
1526 {
1527         u32 sid, tsid;
1528
1529         sid = current_sid();
1530         tsid = task_sid(tsk);
1531         return avc_has_perm(sid, tsid, SECCLASS_PROCESS, perms, NULL);
1532 }
1533
1534 #if CAP_LAST_CAP > 63
1535 #error Fix SELinux to handle capabilities > 63.
1536 #endif
1537
1538 /* Check whether a task is allowed to use a capability. */
1539 static int cred_has_capability(const struct cred *cred,
1540                                int cap, int audit)
1541 {
1542         struct common_audit_data ad;
1543         struct av_decision avd;
1544         u16 sclass;
1545         u32 sid = cred_sid(cred);
1546         u32 av = CAP_TO_MASK(cap);
1547         int rc;
1548
1549         ad.type = LSM_AUDIT_DATA_CAP;
1550         ad.u.cap = cap;
1551
1552         switch (CAP_TO_INDEX(cap)) {
1553         case 0:
1554                 sclass = SECCLASS_CAPABILITY;
1555                 break;
1556         case 1:
1557                 sclass = SECCLASS_CAPABILITY2;
1558                 break;
1559         default:
1560                 printk(KERN_ERR
1561                        "SELinux:  out of range capability %d\n", cap);
1562                 BUG();
1563                 return -EINVAL;
1564         }
1565
1566         rc = avc_has_perm_noaudit(sid, sid, sclass, av, 0, &avd);
1567         if (audit == SECURITY_CAP_AUDIT) {
1568                 int rc2 = avc_audit(sid, sid, sclass, av, &avd, rc, &ad);
1569                 if (rc2)
1570                         return rc2;
1571         }
1572         return rc;
1573 }
1574
1575 /* Check whether a task is allowed to use a system operation. */
1576 static int task_has_system(struct task_struct *tsk,
1577                            u32 perms)
1578 {
1579         u32 sid = task_sid(tsk);
1580
1581         return avc_has_perm(sid, SECINITSID_KERNEL,
1582                             SECCLASS_SYSTEM, perms, NULL);
1583 }
1584
1585 /* Check whether a task has a particular permission to an inode.
1586    The 'adp' parameter is optional and allows other audit
1587    data to be passed (e.g. the dentry). */
1588 static int inode_has_perm(const struct cred *cred,
1589                           struct inode *inode,
1590                           u32 perms,
1591                           struct common_audit_data *adp)
1592 {
1593         struct inode_security_struct *isec;
1594         u32 sid;
1595
1596         validate_creds(cred);
1597
1598         if (unlikely(IS_PRIVATE(inode)))
1599                 return 0;
1600
1601         sid = cred_sid(cred);
1602         isec = inode->i_security;
1603
1604         return avc_has_perm(sid, isec->sid, isec->sclass, perms, adp);
1605 }
1606
1607 /* Same as inode_has_perm, but pass explicit audit data containing
1608    the dentry to help the auditing code to more easily generate the
1609    pathname if needed. */
1610 static inline int dentry_has_perm(const struct cred *cred,
1611                                   struct dentry *dentry,
1612                                   u32 av)
1613 {
1614         struct inode *inode = d_backing_inode(dentry);
1615         struct common_audit_data ad;
1616
1617         ad.type = LSM_AUDIT_DATA_DENTRY;
1618         ad.u.dentry = dentry;
1619         return inode_has_perm(cred, inode, av, &ad);
1620 }
1621
1622 /* Same as inode_has_perm, but pass explicit audit data containing
1623    the path to help the auditing code to more easily generate the
1624    pathname if needed. */
1625 static inline int path_has_perm(const struct cred *cred,
1626                                 const struct path *path,
1627                                 u32 av)
1628 {
1629         struct inode *inode = d_backing_inode(path->dentry);
1630         struct common_audit_data ad;
1631
1632         ad.type = LSM_AUDIT_DATA_PATH;
1633         ad.u.path = *path;
1634         return inode_has_perm(cred, inode, av, &ad);
1635 }
1636
1637 /* Same as path_has_perm, but uses the inode from the file struct. */
1638 static inline int file_path_has_perm(const struct cred *cred,
1639                                      struct file *file,
1640                                      u32 av)
1641 {
1642         struct common_audit_data ad;
1643
1644         ad.type = LSM_AUDIT_DATA_PATH;
1645         ad.u.path = file->f_path;
1646         return inode_has_perm(cred, file_inode(file), av, &ad);
1647 }
1648
1649 /* Check whether a task can use an open file descriptor to
1650    access an inode in a given way.  Check access to the
1651    descriptor itself, and then use dentry_has_perm to
1652    check a particular permission to the file.
1653    Access to the descriptor is implicitly granted if it
1654    has the same SID as the process.  If av is zero, then
1655    access to the file is not checked, e.g. for cases
1656    where only the descriptor is affected like seek. */
1657 static int file_has_perm(const struct cred *cred,
1658                          struct file *file,
1659                          u32 av)
1660 {
1661         struct file_security_struct *fsec = file->f_security;
1662         struct inode *inode = file_inode(file);
1663         struct common_audit_data ad;
1664         u32 sid = cred_sid(cred);
1665         int rc;
1666
1667         ad.type = LSM_AUDIT_DATA_PATH;
1668         ad.u.path = file->f_path;
1669
1670         if (sid != fsec->sid) {
1671                 rc = avc_has_perm(sid, fsec->sid,
1672                                   SECCLASS_FD,
1673                                   FD__USE,
1674                                   &ad);
1675                 if (rc)
1676                         goto out;
1677         }
1678
1679         /* av is zero if only checking access to the descriptor. */
1680         rc = 0;
1681         if (av)
1682                 rc = inode_has_perm(cred, inode, av, &ad);
1683
1684 out:
1685         return rc;
1686 }
1687
1688 /* Check whether a task can create a file. */
1689 static int may_create(struct inode *dir,
1690                       struct dentry *dentry,
1691                       u16 tclass)
1692 {
1693         const struct task_security_struct *tsec = current_security();
1694         struct inode_security_struct *dsec;
1695         struct superblock_security_struct *sbsec;
1696         u32 sid, newsid;
1697         struct common_audit_data ad;
1698         int rc;
1699
1700         dsec = dir->i_security;
1701         sbsec = dir->i_sb->s_security;
1702
1703         sid = tsec->sid;
1704         newsid = tsec->create_sid;
1705
1706         ad.type = LSM_AUDIT_DATA_DENTRY;
1707         ad.u.dentry = dentry;
1708
1709         rc = avc_has_perm(sid, dsec->sid, SECCLASS_DIR,
1710                           DIR__ADD_NAME | DIR__SEARCH,
1711                           &ad);
1712         if (rc)
1713                 return rc;
1714
1715         if (!newsid || !(sbsec->flags & SBLABEL_MNT)) {
1716                 rc = security_transition_sid(sid, dsec->sid, tclass,
1717                                              &dentry->d_name, &newsid);
1718                 if (rc)
1719                         return rc;
1720         }
1721
1722         rc = avc_has_perm(sid, newsid, tclass, FILE__CREATE, &ad);
1723         if (rc)
1724                 return rc;
1725
1726         return avc_has_perm(newsid, sbsec->sid,
1727                             SECCLASS_FILESYSTEM,
1728                             FILESYSTEM__ASSOCIATE, &ad);
1729 }
1730
1731 /* Check whether a task can create a key. */
1732 static int may_create_key(u32 ksid,
1733                           struct task_struct *ctx)
1734 {
1735         u32 sid = task_sid(ctx);
1736
1737         return avc_has_perm(sid, ksid, SECCLASS_KEY, KEY__CREATE, NULL);
1738 }
1739
1740 #define MAY_LINK        0
1741 #define MAY_UNLINK      1
1742 #define MAY_RMDIR       2
1743
1744 /* Check whether a task can link, unlink, or rmdir a file/directory. */
1745 static int may_link(struct inode *dir,
1746                     struct dentry *dentry,
1747                     int kind)
1748
1749 {
1750         struct inode_security_struct *dsec, *isec;
1751         struct common_audit_data ad;
1752         u32 sid = current_sid();
1753         u32 av;
1754         int rc;
1755
1756         dsec = dir->i_security;
1757         isec = d_backing_inode(dentry)->i_security;
1758
1759         ad.type = LSM_AUDIT_DATA_DENTRY;
1760         ad.u.dentry = dentry;
1761
1762         av = DIR__SEARCH;
1763         av |= (kind ? DIR__REMOVE_NAME : DIR__ADD_NAME);
1764         rc = avc_has_perm(sid, dsec->sid, SECCLASS_DIR, av, &ad);
1765         if (rc)
1766                 return rc;
1767
1768         switch (kind) {
1769         case MAY_LINK:
1770                 av = FILE__LINK;
1771                 break;
1772         case MAY_UNLINK:
1773                 av = FILE__UNLINK;
1774                 break;
1775         case MAY_RMDIR:
1776                 av = DIR__RMDIR;
1777                 break;
1778         default:
1779                 printk(KERN_WARNING "SELinux: %s:  unrecognized kind %d\n",
1780                         __func__, kind);
1781                 return 0;
1782         }
1783
1784         rc = avc_has_perm(sid, isec->sid, isec->sclass, av, &ad);
1785         return rc;
1786 }
1787
1788 static inline int may_rename(struct inode *old_dir,
1789                              struct dentry *old_dentry,
1790                              struct inode *new_dir,
1791                              struct dentry *new_dentry)
1792 {
1793         struct inode_security_struct *old_dsec, *new_dsec, *old_isec, *new_isec;
1794         struct common_audit_data ad;
1795         u32 sid = current_sid();
1796         u32 av;
1797         int old_is_dir, new_is_dir;
1798         int rc;
1799
1800         old_dsec = old_dir->i_security;
1801         old_isec = d_backing_inode(old_dentry)->i_security;
1802         old_is_dir = d_is_dir(old_dentry);
1803         new_dsec = new_dir->i_security;
1804
1805         ad.type = LSM_AUDIT_DATA_DENTRY;
1806
1807         ad.u.dentry = old_dentry;
1808         rc = avc_has_perm(sid, old_dsec->sid, SECCLASS_DIR,
1809                           DIR__REMOVE_NAME | DIR__SEARCH, &ad);
1810         if (rc)
1811                 return rc;
1812         rc = avc_has_perm(sid, old_isec->sid,
1813                           old_isec->sclass, FILE__RENAME, &ad);
1814         if (rc)
1815                 return rc;
1816         if (old_is_dir && new_dir != old_dir) {
1817                 rc = avc_has_perm(sid, old_isec->sid,
1818                                   old_isec->sclass, DIR__REPARENT, &ad);
1819                 if (rc)
1820                         return rc;
1821         }
1822
1823         ad.u.dentry = new_dentry;
1824         av = DIR__ADD_NAME | DIR__SEARCH;
1825         if (d_is_positive(new_dentry))
1826                 av |= DIR__REMOVE_NAME;
1827         rc = avc_has_perm(sid, new_dsec->sid, SECCLASS_DIR, av, &ad);
1828         if (rc)
1829                 return rc;
1830         if (d_is_positive(new_dentry)) {
1831                 new_isec = d_backing_inode(new_dentry)->i_security;
1832                 new_is_dir = d_is_dir(new_dentry);
1833                 rc = avc_has_perm(sid, new_isec->sid,
1834                                   new_isec->sclass,
1835                                   (new_is_dir ? DIR__RMDIR : FILE__UNLINK), &ad);
1836                 if (rc)
1837                         return rc;
1838         }
1839
1840         return 0;
1841 }
1842
1843 /* Check whether a task can perform a filesystem operation. */
1844 static int superblock_has_perm(const struct cred *cred,
1845                                struct super_block *sb,
1846                                u32 perms,
1847                                struct common_audit_data *ad)
1848 {
1849         struct superblock_security_struct *sbsec;
1850         u32 sid = cred_sid(cred);
1851
1852         sbsec = sb->s_security;
1853         return avc_has_perm(sid, sbsec->sid, SECCLASS_FILESYSTEM, perms, ad);
1854 }
1855
1856 /* Convert a Linux mode and permission mask to an access vector. */
1857 static inline u32 file_mask_to_av(int mode, int mask)
1858 {
1859         u32 av = 0;
1860
1861         if (!S_ISDIR(mode)) {
1862                 if (mask & MAY_EXEC)
1863                         av |= FILE__EXECUTE;
1864                 if (mask & MAY_READ)
1865                         av |= FILE__READ;
1866
1867                 if (mask & MAY_APPEND)
1868                         av |= FILE__APPEND;
1869                 else if (mask & MAY_WRITE)
1870                         av |= FILE__WRITE;
1871
1872         } else {
1873                 if (mask & MAY_EXEC)
1874                         av |= DIR__SEARCH;
1875                 if (mask & MAY_WRITE)
1876                         av |= DIR__WRITE;
1877                 if (mask & MAY_READ)
1878                         av |= DIR__READ;
1879         }
1880
1881         return av;
1882 }
1883
1884 /* Convert a Linux file to an access vector. */
1885 static inline u32 file_to_av(struct file *file)
1886 {
1887         u32 av = 0;
1888
1889         if (file->f_mode & FMODE_READ)
1890                 av |= FILE__READ;
1891         if (file->f_mode & FMODE_WRITE) {
1892                 if (file->f_flags & O_APPEND)
1893                         av |= FILE__APPEND;
1894                 else
1895                         av |= FILE__WRITE;
1896         }
1897         if (!av) {
1898                 /*
1899                  * Special file opened with flags 3 for ioctl-only use.
1900                  */
1901                 av = FILE__IOCTL;
1902         }
1903
1904         return av;
1905 }
1906
1907 /*
1908  * Convert a file to an access vector and include the correct open
1909  * open permission.
1910  */
1911 static inline u32 open_file_to_av(struct file *file)
1912 {
1913         u32 av = file_to_av(file);
1914
1915         if (selinux_policycap_openperm)
1916                 av |= FILE__OPEN;
1917
1918         return av;
1919 }
1920
1921 /* Hook functions begin here. */
1922
1923 static int selinux_binder_set_context_mgr(struct task_struct *mgr)
1924 {
1925         u32 mysid = current_sid();
1926         u32 mgrsid = task_sid(mgr);
1927
1928         return avc_has_perm(mysid, mgrsid, SECCLASS_BINDER,
1929                             BINDER__SET_CONTEXT_MGR, NULL);
1930 }
1931
1932 static int selinux_binder_transaction(struct task_struct *from,
1933                                       struct task_struct *to)
1934 {
1935         u32 mysid = current_sid();
1936         u32 fromsid = task_sid(from);
1937         u32 tosid = task_sid(to);
1938         int rc;
1939
1940         if (mysid != fromsid) {
1941                 rc = avc_has_perm(mysid, fromsid, SECCLASS_BINDER,
1942                                   BINDER__IMPERSONATE, NULL);
1943                 if (rc)
1944                         return rc;
1945         }
1946
1947         return avc_has_perm(fromsid, tosid, SECCLASS_BINDER, BINDER__CALL,
1948                             NULL);
1949 }
1950
1951 static int selinux_binder_transfer_binder(struct task_struct *from,
1952                                           struct task_struct *to)
1953 {
1954         u32 fromsid = task_sid(from);
1955         u32 tosid = task_sid(to);
1956
1957         return avc_has_perm(fromsid, tosid, SECCLASS_BINDER, BINDER__TRANSFER,
1958                             NULL);
1959 }
1960
1961 static int selinux_binder_transfer_file(struct task_struct *from,
1962                                         struct task_struct *to,
1963                                         struct file *file)
1964 {
1965         u32 sid = task_sid(to);
1966         struct file_security_struct *fsec = file->f_security;
1967         struct inode *inode = d_backing_inode(file->f_path.dentry);
1968         struct inode_security_struct *isec = inode->i_security;
1969         struct common_audit_data ad;
1970         int rc;
1971
1972         ad.type = LSM_AUDIT_DATA_PATH;
1973         ad.u.path = file->f_path;
1974
1975         if (sid != fsec->sid) {
1976                 rc = avc_has_perm(sid, fsec->sid,
1977                                   SECCLASS_FD,
1978                                   FD__USE,
1979                                   &ad);
1980                 if (rc)
1981                         return rc;
1982         }
1983
1984         if (unlikely(IS_PRIVATE(inode)))
1985                 return 0;
1986
1987         return avc_has_perm(sid, isec->sid, isec->sclass, file_to_av(file),
1988                             &ad);
1989 }
1990
1991 static int selinux_ptrace_access_check(struct task_struct *child,
1992                                      unsigned int mode)
1993 {
1994         int rc;
1995
1996         rc = cap_ptrace_access_check(child, mode);
1997         if (rc)
1998                 return rc;
1999
2000         if (mode & PTRACE_MODE_READ) {
2001                 u32 sid = current_sid();
2002                 u32 csid = task_sid(child);
2003                 return avc_has_perm(sid, csid, SECCLASS_FILE, FILE__READ, NULL);
2004         }
2005
2006         return current_has_perm(child, PROCESS__PTRACE);
2007 }
2008
2009 static int selinux_ptrace_traceme(struct task_struct *parent)
2010 {
2011         int rc;
2012
2013         rc = cap_ptrace_traceme(parent);
2014         if (rc)
2015                 return rc;
2016
2017         return task_has_perm(parent, current, PROCESS__PTRACE);
2018 }
2019
2020 static int selinux_capget(struct task_struct *target, kernel_cap_t *effective,
2021                           kernel_cap_t *inheritable, kernel_cap_t *permitted)
2022 {
2023         int error;
2024
2025         error = current_has_perm(target, PROCESS__GETCAP);
2026         if (error)
2027                 return error;
2028
2029         return cap_capget(target, effective, inheritable, permitted);
2030 }
2031
2032 static int selinux_capset(struct cred *new, const struct cred *old,
2033                           const kernel_cap_t *effective,
2034                           const kernel_cap_t *inheritable,
2035                           const kernel_cap_t *permitted)
2036 {
2037         int error;
2038
2039         error = cap_capset(new, old,
2040                                       effective, inheritable, permitted);
2041         if (error)
2042                 return error;
2043
2044         return cred_has_perm(old, new, PROCESS__SETCAP);
2045 }
2046
2047 /*
2048  * (This comment used to live with the selinux_task_setuid hook,
2049  * which was removed).
2050  *
2051  * Since setuid only affects the current process, and since the SELinux
2052  * controls are not based on the Linux identity attributes, SELinux does not
2053  * need to control this operation.  However, SELinux does control the use of
2054  * the CAP_SETUID and CAP_SETGID capabilities using the capable hook.
2055  */
2056
2057 static int selinux_capable(const struct cred *cred, struct user_namespace *ns,
2058                            int cap, int audit)
2059 {
2060         int rc;
2061
2062         rc = cap_capable(cred, ns, cap, audit);
2063         if (rc)
2064                 return rc;
2065
2066         return cred_has_capability(cred, cap, audit);
2067 }
2068
2069 static int selinux_quotactl(int cmds, int type, int id, struct super_block *sb)
2070 {
2071         const struct cred *cred = current_cred();
2072         int rc = 0;
2073
2074         if (!sb)
2075                 return 0;
2076
2077         switch (cmds) {
2078         case Q_SYNC:
2079         case Q_QUOTAON:
2080         case Q_QUOTAOFF:
2081         case Q_SETINFO:
2082         case Q_SETQUOTA:
2083                 rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAMOD, NULL);
2084                 break;
2085         case Q_GETFMT:
2086         case Q_GETINFO:
2087         case Q_GETQUOTA:
2088                 rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAGET, NULL);
2089                 break;
2090         default:
2091                 rc = 0;  /* let the kernel handle invalid cmds */
2092                 break;
2093         }
2094         return rc;
2095 }
2096
2097 static int selinux_quota_on(struct dentry *dentry)
2098 {
2099         const struct cred *cred = current_cred();
2100
2101         return dentry_has_perm(cred, dentry, FILE__QUOTAON);
2102 }
2103
2104 static int selinux_syslog(int type)
2105 {
2106         int rc;
2107
2108         switch (type) {
2109         case SYSLOG_ACTION_READ_ALL:    /* Read last kernel messages */
2110         case SYSLOG_ACTION_SIZE_BUFFER: /* Return size of the log buffer */
2111                 rc = task_has_system(current, SYSTEM__SYSLOG_READ);
2112                 break;
2113         case SYSLOG_ACTION_CONSOLE_OFF: /* Disable logging to console */
2114         case SYSLOG_ACTION_CONSOLE_ON:  /* Enable logging to console */
2115         /* Set level of messages printed to console */
2116         case SYSLOG_ACTION_CONSOLE_LEVEL:
2117                 rc = task_has_system(current, SYSTEM__SYSLOG_CONSOLE);
2118                 break;
2119         case SYSLOG_ACTION_CLOSE:       /* Close log */
2120         case SYSLOG_ACTION_OPEN:        /* Open log */
2121         case SYSLOG_ACTION_READ:        /* Read from log */
2122         case SYSLOG_ACTION_READ_CLEAR:  /* Read/clear last kernel messages */
2123         case SYSLOG_ACTION_CLEAR:       /* Clear ring buffer */
2124         default:
2125                 rc = task_has_system(current, SYSTEM__SYSLOG_MOD);
2126                 break;
2127         }
2128         return rc;
2129 }
2130
2131 /*
2132  * Check that a process has enough memory to allocate a new virtual
2133  * mapping. 0 means there is enough memory for the allocation to
2134  * succeed and -ENOMEM implies there is not.
2135  *
2136  * Do not audit the selinux permission check, as this is applied to all
2137  * processes that allocate mappings.
2138  */
2139 static int selinux_vm_enough_memory(struct mm_struct *mm, long pages)
2140 {
2141         int rc, cap_sys_admin = 0;
2142
2143         rc = selinux_capable(current_cred(), &init_user_ns, CAP_SYS_ADMIN,
2144                              SECURITY_CAP_NOAUDIT);
2145         if (rc == 0)
2146                 cap_sys_admin = 1;
2147
2148         return __vm_enough_memory(mm, pages, cap_sys_admin);
2149 }
2150
2151 /* binprm security operations */
2152
2153 static int check_nnp_nosuid(const struct linux_binprm *bprm,
2154                             const struct task_security_struct *old_tsec,
2155                             const struct task_security_struct *new_tsec)
2156 {
2157         int nnp = (bprm->unsafe & LSM_UNSAFE_NO_NEW_PRIVS);
2158         int nosuid = (bprm->file->f_path.mnt->mnt_flags & MNT_NOSUID);
2159         int rc;
2160
2161         if (!nnp && !nosuid)
2162                 return 0; /* neither NNP nor nosuid */
2163
2164         if (new_tsec->sid == old_tsec->sid)
2165                 return 0; /* No change in credentials */
2166
2167         /*
2168          * The only transitions we permit under NNP or nosuid
2169          * are transitions to bounded SIDs, i.e. SIDs that are
2170          * guaranteed to only be allowed a subset of the permissions
2171          * of the current SID.
2172          */
2173         rc = security_bounded_transition(old_tsec->sid, new_tsec->sid);
2174         if (rc) {
2175                 /*
2176                  * On failure, preserve the errno values for NNP vs nosuid.
2177                  * NNP:  Operation not permitted for caller.
2178                  * nosuid:  Permission denied to file.
2179                  */
2180                 if (nnp)
2181                         return -EPERM;
2182                 else
2183                         return -EACCES;
2184         }
2185         return 0;
2186 }
2187
2188 static int selinux_bprm_set_creds(struct linux_binprm *bprm)
2189 {
2190         const struct task_security_struct *old_tsec;
2191         struct task_security_struct *new_tsec;
2192         struct inode_security_struct *isec;
2193         struct common_audit_data ad;
2194         struct inode *inode = file_inode(bprm->file);
2195         int rc;
2196
2197         rc = cap_bprm_set_creds(bprm);
2198         if (rc)
2199                 return rc;
2200
2201         /* SELinux context only depends on initial program or script and not
2202          * the script interpreter */
2203         if (bprm->cred_prepared)
2204                 return 0;
2205
2206         old_tsec = current_security();
2207         new_tsec = bprm->cred->security;
2208         isec = inode->i_security;
2209
2210         /* Default to the current task SID. */
2211         new_tsec->sid = old_tsec->sid;
2212         new_tsec->osid = old_tsec->sid;
2213
2214         /* Reset fs, key, and sock SIDs on execve. */
2215         new_tsec->create_sid = 0;
2216         new_tsec->keycreate_sid = 0;
2217         new_tsec->sockcreate_sid = 0;
2218
2219         if (old_tsec->exec_sid) {
2220                 new_tsec->sid = old_tsec->exec_sid;
2221                 /* Reset exec SID on execve. */
2222                 new_tsec->exec_sid = 0;
2223
2224                 /* Fail on NNP or nosuid if not an allowed transition. */
2225                 rc = check_nnp_nosuid(bprm, old_tsec, new_tsec);
2226                 if (rc)
2227                         return rc;
2228         } else {
2229                 /* Check for a default transition on this program. */
2230                 rc = security_transition_sid(old_tsec->sid, isec->sid,
2231                                              SECCLASS_PROCESS, NULL,
2232                                              &new_tsec->sid);
2233                 if (rc)
2234                         return rc;
2235
2236                 /*
2237                  * Fallback to old SID on NNP or nosuid if not an allowed
2238                  * transition.
2239                  */
2240                 rc = check_nnp_nosuid(bprm, old_tsec, new_tsec);
2241                 if (rc)
2242                         new_tsec->sid = old_tsec->sid;
2243         }
2244
2245         ad.type = LSM_AUDIT_DATA_PATH;
2246         ad.u.path = bprm->file->f_path;
2247
2248         if (new_tsec->sid == old_tsec->sid) {
2249                 rc = avc_has_perm(old_tsec->sid, isec->sid,
2250                                   SECCLASS_FILE, FILE__EXECUTE_NO_TRANS, &ad);
2251                 if (rc)
2252                         return rc;
2253         } else {
2254                 /* Check permissions for the transition. */
2255                 rc = avc_has_perm(old_tsec->sid, new_tsec->sid,
2256                                   SECCLASS_PROCESS, PROCESS__TRANSITION, &ad);
2257                 if (rc)
2258                         return rc;
2259
2260                 rc = avc_has_perm(new_tsec->sid, isec->sid,
2261                                   SECCLASS_FILE, FILE__ENTRYPOINT, &ad);
2262                 if (rc)
2263                         return rc;
2264
2265                 /* Check for shared state */
2266                 if (bprm->unsafe & LSM_UNSAFE_SHARE) {
2267                         rc = avc_has_perm(old_tsec->sid, new_tsec->sid,
2268                                           SECCLASS_PROCESS, PROCESS__SHARE,
2269                                           NULL);
2270                         if (rc)
2271                                 return -EPERM;
2272                 }
2273
2274                 /* Make sure that anyone attempting to ptrace over a task that
2275                  * changes its SID has the appropriate permit */
2276                 if (bprm->unsafe &
2277                     (LSM_UNSAFE_PTRACE | LSM_UNSAFE_PTRACE_CAP)) {
2278                         struct task_struct *tracer;
2279                         struct task_security_struct *sec;
2280                         u32 ptsid = 0;
2281
2282                         rcu_read_lock();
2283                         tracer = ptrace_parent(current);
2284                         if (likely(tracer != NULL)) {
2285                                 sec = __task_cred(tracer)->security;
2286                                 ptsid = sec->sid;
2287                         }
2288                         rcu_read_unlock();
2289
2290                         if (ptsid != 0) {
2291                                 rc = avc_has_perm(ptsid, new_tsec->sid,
2292                                                   SECCLASS_PROCESS,
2293                                                   PROCESS__PTRACE, NULL);
2294                                 if (rc)
2295                                         return -EPERM;
2296                         }
2297                 }
2298
2299                 /* Clear any possibly unsafe personality bits on exec: */
2300                 bprm->per_clear |= PER_CLEAR_ON_SETID;
2301         }
2302
2303         return 0;
2304 }
2305
2306 static int selinux_bprm_secureexec(struct linux_binprm *bprm)
2307 {
2308         const struct task_security_struct *tsec = current_security();
2309         u32 sid, osid;
2310         int atsecure = 0;
2311
2312         sid = tsec->sid;
2313         osid = tsec->osid;
2314
2315         if (osid != sid) {
2316                 /* Enable secure mode for SIDs transitions unless
2317                    the noatsecure permission is granted between
2318                    the two SIDs, i.e. ahp returns 0. */
2319                 atsecure = avc_has_perm(osid, sid,
2320                                         SECCLASS_PROCESS,
2321                                         PROCESS__NOATSECURE, NULL);
2322         }
2323
2324         return (atsecure || cap_bprm_secureexec(bprm));
2325 }
2326
2327 static int match_file(const void *p, struct file *file, unsigned fd)
2328 {
2329         return file_has_perm(p, file, file_to_av(file)) ? fd + 1 : 0;
2330 }
2331
2332 /* Derived from fs/exec.c:flush_old_files. */
2333 static inline void flush_unauthorized_files(const struct cred *cred,
2334                                             struct files_struct *files)
2335 {
2336         struct file *file, *devnull = NULL;
2337         struct tty_struct *tty;
2338         int drop_tty = 0;
2339         unsigned n;
2340
2341         tty = get_current_tty();
2342         if (tty) {
2343                 spin_lock(&tty_files_lock);
2344                 if (!list_empty(&tty->tty_files)) {
2345                         struct tty_file_private *file_priv;
2346
2347                         /* Revalidate access to controlling tty.
2348                            Use file_path_has_perm on the tty path directly
2349                            rather than using file_has_perm, as this particular
2350                            open file may belong to another process and we are
2351                            only interested in the inode-based check here. */
2352                         file_priv = list_first_entry(&tty->tty_files,
2353                                                 struct tty_file_private, list);
2354                         file = file_priv->file;
2355                         if (file_path_has_perm(cred, file, FILE__READ | FILE__WRITE))
2356                                 drop_tty = 1;
2357                 }
2358                 spin_unlock(&tty_files_lock);
2359                 tty_kref_put(tty);
2360         }
2361         /* Reset controlling tty. */
2362         if (drop_tty)
2363                 no_tty();
2364
2365         /* Revalidate access to inherited open files. */
2366         n = iterate_fd(files, 0, match_file, cred);
2367         if (!n) /* none found? */
2368                 return;
2369
2370         devnull = dentry_open(&selinux_null, O_RDWR, cred);
2371         if (IS_ERR(devnull))
2372                 devnull = NULL;
2373         /* replace all the matching ones with this */
2374         do {
2375                 replace_fd(n - 1, devnull, 0);
2376         } while ((n = iterate_fd(files, n, match_file, cred)) != 0);
2377         if (devnull)
2378                 fput(devnull);
2379 }
2380
2381 /*
2382  * Prepare a process for imminent new credential changes due to exec
2383  */
2384 static void selinux_bprm_committing_creds(struct linux_binprm *bprm)
2385 {
2386         struct task_security_struct *new_tsec;
2387         struct rlimit *rlim, *initrlim;
2388         int rc, i;
2389
2390         new_tsec = bprm->cred->security;
2391         if (new_tsec->sid == new_tsec->osid)
2392                 return;
2393
2394         /* Close files for which the new task SID is not authorized. */
2395         flush_unauthorized_files(bprm->cred, current->files);
2396
2397         /* Always clear parent death signal on SID transitions. */
2398         current->pdeath_signal = 0;
2399
2400         /* Check whether the new SID can inherit resource limits from the old
2401          * SID.  If not, reset all soft limits to the lower of the current
2402          * task's hard limit and the init task's soft limit.
2403          *
2404          * Note that the setting of hard limits (even to lower them) can be
2405          * controlled by the setrlimit check.  The inclusion of the init task's
2406          * soft limit into the computation is to avoid resetting soft limits
2407          * higher than the default soft limit for cases where the default is
2408          * lower than the hard limit, e.g. RLIMIT_CORE or RLIMIT_STACK.
2409          */
2410         rc = avc_has_perm(new_tsec->osid, new_tsec->sid, SECCLASS_PROCESS,
2411                           PROCESS__RLIMITINH, NULL);
2412         if (rc) {
2413                 /* protect against do_prlimit() */
2414                 task_lock(current);
2415                 for (i = 0; i < RLIM_NLIMITS; i++) {
2416                         rlim = current->signal->rlim + i;
2417                         initrlim = init_task.signal->rlim + i;
2418                         rlim->rlim_cur = min(rlim->rlim_max, initrlim->rlim_cur);
2419                 }
2420                 task_unlock(current);
2421                 update_rlimit_cpu(current, rlimit(RLIMIT_CPU));
2422         }
2423 }
2424
2425 /*
2426  * Clean up the process immediately after the installation of new credentials
2427  * due to exec
2428  */
2429 static void selinux_bprm_committed_creds(struct linux_binprm *bprm)
2430 {
2431         const struct task_security_struct *tsec = current_security();
2432         struct itimerval itimer;
2433         u32 osid, sid;
2434         int rc, i;
2435
2436         osid = tsec->osid;
2437         sid = tsec->sid;
2438
2439         if (sid == osid)
2440                 return;
2441
2442         /* Check whether the new SID can inherit signal state from the old SID.
2443          * If not, clear itimers to avoid subsequent signal generation and
2444          * flush and unblock signals.
2445          *
2446          * This must occur _after_ the task SID has been updated so that any
2447          * kill done after the flush will be checked against the new SID.
2448          */
2449         rc = avc_has_perm(osid, sid, SECCLASS_PROCESS, PROCESS__SIGINH, NULL);
2450         if (rc) {
2451                 memset(&itimer, 0, sizeof itimer);
2452                 for (i = 0; i < 3; i++)
2453                         do_setitimer(i, &itimer, NULL);
2454                 spin_lock_irq(&current->sighand->siglock);
2455                 if (!(current->signal->flags & SIGNAL_GROUP_EXIT)) {
2456                         __flush_signals(current);
2457                         flush_signal_handlers(current, 1);
2458                         sigemptyset(&current->blocked);
2459                 }
2460                 spin_unlock_irq(&current->sighand->siglock);
2461         }
2462
2463         /* Wake up the parent if it is waiting so that it can recheck
2464          * wait permission to the new task SID. */
2465         read_lock(&tasklist_lock);
2466         __wake_up_parent(current, current->real_parent);
2467         read_unlock(&tasklist_lock);
2468 }
2469
2470 /* superblock security operations */
2471
2472 static int selinux_sb_alloc_security(struct super_block *sb)
2473 {
2474         return superblock_alloc_security(sb);
2475 }
2476
2477 static void selinux_sb_free_security(struct super_block *sb)
2478 {
2479         superblock_free_security(sb);
2480 }
2481
2482 static inline int match_prefix(char *prefix, int plen, char *option, int olen)
2483 {
2484         if (plen > olen)
2485                 return 0;
2486
2487         return !memcmp(prefix, option, plen);
2488 }
2489
2490 static inline int selinux_option(char *option, int len)
2491 {
2492         return (match_prefix(CONTEXT_STR, sizeof(CONTEXT_STR)-1, option, len) ||
2493                 match_prefix(FSCONTEXT_STR, sizeof(FSCONTEXT_STR)-1, option, len) ||
2494                 match_prefix(DEFCONTEXT_STR, sizeof(DEFCONTEXT_STR)-1, option, len) ||
2495                 match_prefix(ROOTCONTEXT_STR, sizeof(ROOTCONTEXT_STR)-1, option, len) ||
2496                 match_prefix(LABELSUPP_STR, sizeof(LABELSUPP_STR)-1, option, len));
2497 }
2498
2499 static inline void take_option(char **to, char *from, int *first, int len)
2500 {
2501         if (!*first) {
2502                 **to = ',';
2503                 *to += 1;
2504         } else
2505                 *first = 0;
2506         memcpy(*to, from, len);
2507         *to += len;
2508 }
2509
2510 static inline void take_selinux_option(char **to, char *from, int *first,
2511                                        int len)
2512 {
2513         int current_size = 0;
2514
2515         if (!*first) {
2516                 **to = '|';
2517                 *to += 1;
2518         } else
2519                 *first = 0;
2520
2521         while (current_size < len) {
2522                 if (*from != '"') {
2523                         **to = *from;
2524                         *to += 1;
2525                 }
2526                 from += 1;
2527                 current_size += 1;
2528         }
2529 }
2530
2531 static int selinux_sb_copy_data(char *orig, char *copy)
2532 {
2533         int fnosec, fsec, rc = 0;
2534         char *in_save, *in_curr, *in_end;
2535         char *sec_curr, *nosec_save, *nosec;
2536         int open_quote = 0;
2537
2538         in_curr = orig;
2539         sec_curr = copy;
2540
2541         nosec = (char *)get_zeroed_page(GFP_KERNEL);
2542         if (!nosec) {
2543                 rc = -ENOMEM;
2544                 goto out;
2545         }
2546
2547         nosec_save = nosec;
2548         fnosec = fsec = 1;
2549         in_save = in_end = orig;
2550
2551         do {
2552                 if (*in_end == '"')
2553                         open_quote = !open_quote;
2554                 if ((*in_end == ',' && open_quote == 0) ||
2555                                 *in_end == '\0') {
2556                         int len = in_end - in_curr;
2557
2558                         if (selinux_option(in_curr, len))
2559                                 take_selinux_option(&sec_curr, in_curr, &fsec, len);
2560                         else
2561                                 take_option(&nosec, in_curr, &fnosec, len);
2562
2563                         in_curr = in_end + 1;
2564                 }
2565         } while (*in_end++);
2566
2567         strcpy(in_save, nosec_save);
2568         free_page((unsigned long)nosec_save);
2569 out:
2570         return rc;
2571 }
2572
2573 static int selinux_sb_remount(struct super_block *sb, void *data)
2574 {
2575         int rc, i, *flags;
2576         struct security_mnt_opts opts;
2577         char *secdata, **mount_options;
2578         struct superblock_security_struct *sbsec = sb->s_security;
2579
2580         if (!(sbsec->flags & SE_SBINITIALIZED))
2581                 return 0;
2582
2583         if (!data)
2584                 return 0;
2585
2586         if (sb->s_type->fs_flags & FS_BINARY_MOUNTDATA)
2587                 return 0;
2588
2589         security_init_mnt_opts(&opts);
2590         secdata = alloc_secdata();
2591         if (!secdata)
2592                 return -ENOMEM;
2593         rc = selinux_sb_copy_data(data, secdata);
2594         if (rc)
2595                 goto out_free_secdata;
2596
2597         rc = selinux_parse_opts_str(secdata, &opts);
2598         if (rc)
2599                 goto out_free_secdata;
2600
2601         mount_options = opts.mnt_opts;
2602         flags = opts.mnt_opts_flags;
2603
2604         for (i = 0; i < opts.num_mnt_opts; i++) {
2605                 u32 sid;
2606                 size_t len;
2607
2608                 if (flags[i] == SBLABEL_MNT)
2609                         continue;
2610                 len = strlen(mount_options[i]);
2611                 rc = security_context_to_sid(mount_options[i], len, &sid,
2612                                              GFP_KERNEL);
2613                 if (rc) {
2614                         printk(KERN_WARNING "SELinux: security_context_to_sid"
2615                                "(%s) failed for (dev %s, type %s) errno=%d\n",
2616                                mount_options[i], sb->s_id, sb->s_type->name, rc);
2617                         goto out_free_opts;
2618                 }
2619                 rc = -EINVAL;
2620                 switch (flags[i]) {
2621                 case FSCONTEXT_MNT:
2622                         if (bad_option(sbsec, FSCONTEXT_MNT, sbsec->sid, sid))
2623                                 goto out_bad_option;
2624                         break;
2625                 case CONTEXT_MNT:
2626                         if (bad_option(sbsec, CONTEXT_MNT, sbsec->mntpoint_sid, sid))
2627                                 goto out_bad_option;
2628                         break;
2629                 case ROOTCONTEXT_MNT: {
2630                         struct inode_security_struct *root_isec;
2631                         root_isec = d_backing_inode(sb->s_root)->i_security;
2632
2633                         if (bad_option(sbsec, ROOTCONTEXT_MNT, root_isec->sid, sid))
2634                                 goto out_bad_option;
2635                         break;
2636                 }
2637                 case DEFCONTEXT_MNT:
2638                         if (bad_option(sbsec, DEFCONTEXT_MNT, sbsec->def_sid, sid))
2639                                 goto out_bad_option;
2640                         break;
2641                 default:
2642                         goto out_free_opts;
2643                 }
2644         }
2645
2646         rc = 0;
2647 out_free_opts:
2648         security_free_mnt_opts(&opts);
2649 out_free_secdata:
2650         free_secdata(secdata);
2651         return rc;
2652 out_bad_option:
2653         printk(KERN_WARNING "SELinux: unable to change security options "
2654                "during remount (dev %s, type=%s)\n", sb->s_id,
2655                sb->s_type->name);
2656         goto out_free_opts;
2657 }
2658
2659 static int selinux_sb_kern_mount(struct super_block *sb, int flags, void *data)
2660 {
2661         const struct cred *cred = current_cred();
2662         struct common_audit_data ad;
2663         int rc;
2664
2665         rc = superblock_doinit(sb, data);
2666         if (rc)
2667                 return rc;
2668
2669         /* Allow all mounts performed by the kernel */
2670         if (flags & MS_KERNMOUNT)
2671                 return 0;
2672
2673         ad.type = LSM_AUDIT_DATA_DENTRY;
2674         ad.u.dentry = sb->s_root;
2675         return superblock_has_perm(cred, sb, FILESYSTEM__MOUNT, &ad);
2676 }
2677
2678 static int selinux_sb_statfs(struct dentry *dentry)
2679 {
2680         const struct cred *cred = current_cred();
2681         struct common_audit_data ad;
2682
2683         ad.type = LSM_AUDIT_DATA_DENTRY;
2684         ad.u.dentry = dentry->d_sb->s_root;
2685         return superblock_has_perm(cred, dentry->d_sb, FILESYSTEM__GETATTR, &ad);
2686 }
2687
2688 static int selinux_mount(const char *dev_name,
2689                          struct path *path,
2690                          const char *type,
2691                          unsigned long flags,
2692                          void *data)
2693 {
2694         const struct cred *cred = current_cred();
2695
2696         if (flags & MS_REMOUNT)
2697                 return superblock_has_perm(cred, path->dentry->d_sb,
2698                                            FILESYSTEM__REMOUNT, NULL);
2699         else
2700                 return path_has_perm(cred, path, FILE__MOUNTON);
2701 }
2702
2703 static int selinux_umount(struct vfsmount *mnt, int flags)
2704 {
2705         const struct cred *cred = current_cred();
2706
2707         return superblock_has_perm(cred, mnt->mnt_sb,
2708                                    FILESYSTEM__UNMOUNT, NULL);
2709 }
2710
2711 /* inode security operations */
2712
2713 static int selinux_inode_alloc_security(struct inode *inode)
2714 {
2715         return inode_alloc_security(inode);
2716 }
2717
2718 static void selinux_inode_free_security(struct inode *inode)
2719 {
2720         inode_free_security(inode);
2721 }
2722
2723 static int selinux_dentry_init_security(struct dentry *dentry, int mode,
2724                                         struct qstr *name, void **ctx,
2725                                         u32 *ctxlen)
2726 {
2727         const struct cred *cred = current_cred();
2728         struct task_security_struct *tsec;
2729         struct inode_security_struct *dsec;
2730         struct superblock_security_struct *sbsec;
2731         struct inode *dir = d_backing_inode(dentry->d_parent);
2732         u32 newsid;
2733         int rc;
2734
2735         tsec = cred->security;
2736         dsec = dir->i_security;
2737         sbsec = dir->i_sb->s_security;
2738
2739         if (tsec->create_sid && sbsec->behavior != SECURITY_FS_USE_MNTPOINT) {
2740                 newsid = tsec->create_sid;
2741         } else {
2742                 rc = security_transition_sid(tsec->sid, dsec->sid,
2743                                              inode_mode_to_security_class(mode),
2744                                              name,
2745                                              &newsid);
2746                 if (rc) {
2747                         printk(KERN_WARNING
2748                                 "%s: security_transition_sid failed, rc=%d\n",
2749                                __func__, -rc);
2750                         return rc;
2751                 }
2752         }
2753
2754         return security_sid_to_context(newsid, (char **)ctx, ctxlen);
2755 }
2756
2757 static int selinux_inode_init_security(struct inode *inode, struct inode *dir,
2758                                        const struct qstr *qstr,
2759                                        const char **name,
2760                                        void **value, size_t *len)
2761 {
2762         const struct task_security_struct *tsec = current_security();
2763         struct inode_security_struct *dsec;
2764         struct superblock_security_struct *sbsec;
2765         u32 sid, newsid, clen;
2766         int rc;
2767         char *context;
2768
2769         dsec = dir->i_security;
2770         sbsec = dir->i_sb->s_security;
2771
2772         sid = tsec->sid;
2773         newsid = tsec->create_sid;
2774
2775         if ((sbsec->flags & SE_SBINITIALIZED) &&
2776             (sbsec->behavior == SECURITY_FS_USE_MNTPOINT))
2777                 newsid = sbsec->mntpoint_sid;
2778         else if (!newsid || !(sbsec->flags & SBLABEL_MNT)) {
2779                 rc = security_transition_sid(sid, dsec->sid,
2780                                              inode_mode_to_security_class(inode->i_mode),
2781                                              qstr, &newsid);
2782                 if (rc) {
2783                         printk(KERN_WARNING "%s:  "
2784                                "security_transition_sid failed, rc=%d (dev=%s "
2785                                "ino=%ld)\n",
2786                                __func__,
2787                                -rc, inode->i_sb->s_id, inode->i_ino);
2788                         return rc;
2789                 }
2790         }
2791
2792         /* Possibly defer initialization to selinux_complete_init. */
2793         if (sbsec->flags & SE_SBINITIALIZED) {
2794                 struct inode_security_struct *isec = inode->i_security;
2795                 isec->sclass = inode_mode_to_security_class(inode->i_mode);
2796                 isec->sid = newsid;
2797                 isec->initialized = 1;
2798         }
2799
2800         if (!ss_initialized || !(sbsec->flags & SBLABEL_MNT))
2801                 return -EOPNOTSUPP;
2802
2803         if (name)
2804                 *name = XATTR_SELINUX_SUFFIX;
2805
2806         if (value && len) {
2807                 rc = security_sid_to_context_force(newsid, &context, &clen);
2808                 if (rc)
2809                         return rc;
2810                 *value = context;
2811                 *len = clen;
2812         }
2813
2814         return 0;
2815 }
2816
2817 static int selinux_inode_create(struct inode *dir, struct dentry *dentry, umode_t mode)
2818 {
2819         return may_create(dir, dentry, SECCLASS_FILE);
2820 }
2821
2822 static int selinux_inode_link(struct dentry *old_dentry, struct inode *dir, struct dentry *new_dentry)
2823 {
2824         return may_link(dir, old_dentry, MAY_LINK);
2825 }
2826
2827 static int selinux_inode_unlink(struct inode *dir, struct dentry *dentry)
2828 {
2829         return may_link(dir, dentry, MAY_UNLINK);
2830 }
2831
2832 static int selinux_inode_symlink(struct inode *dir, struct dentry *dentry, const char *name)
2833 {
2834         return may_create(dir, dentry, SECCLASS_LNK_FILE);
2835 }
2836
2837 static int selinux_inode_mkdir(struct inode *dir, struct dentry *dentry, umode_t mask)
2838 {
2839         return may_create(dir, dentry, SECCLASS_DIR);
2840 }
2841
2842 static int selinux_inode_rmdir(struct inode *dir, struct dentry *dentry)
2843 {
2844         return may_link(dir, dentry, MAY_RMDIR);
2845 }
2846
2847 static int selinux_inode_mknod(struct inode *dir, struct dentry *dentry, umode_t mode, dev_t dev)
2848 {
2849         return may_create(dir, dentry, inode_mode_to_security_class(mode));
2850 }
2851
2852 static int selinux_inode_rename(struct inode *old_inode, struct dentry *old_dentry,
2853                                 struct inode *new_inode, struct dentry *new_dentry)
2854 {
2855         return may_rename(old_inode, old_dentry, new_inode, new_dentry);
2856 }
2857
2858 static int selinux_inode_readlink(struct dentry *dentry)
2859 {
2860         const struct cred *cred = current_cred();
2861
2862         return dentry_has_perm(cred, dentry, FILE__READ);
2863 }
2864
2865 static int selinux_inode_follow_link(struct dentry *dentry, struct nameidata *nameidata)
2866 {
2867         const struct cred *cred = current_cred();
2868
2869         return dentry_has_perm(cred, dentry, FILE__READ);
2870 }
2871
2872 static noinline int audit_inode_permission(struct inode *inode,
2873                                            u32 perms, u32 audited, u32 denied,
2874                                            int result,
2875                                            unsigned flags)
2876 {
2877         struct common_audit_data ad;
2878         struct inode_security_struct *isec = inode->i_security;
2879         int rc;
2880
2881         ad.type = LSM_AUDIT_DATA_INODE;
2882         ad.u.inode = inode;
2883
2884         rc = slow_avc_audit(current_sid(), isec->sid, isec->sclass, perms,
2885                             audited, denied, result, &ad, flags);
2886         if (rc)
2887                 return rc;
2888         return 0;
2889 }
2890
2891 static int selinux_inode_permission(struct inode *inode, int mask)
2892 {
2893         const struct cred *cred = current_cred();
2894         u32 perms;
2895         bool from_access;
2896         unsigned flags = mask & MAY_NOT_BLOCK;
2897         struct inode_security_struct *isec;
2898         u32 sid;
2899         struct av_decision avd;
2900         int rc, rc2;
2901         u32 audited, denied;
2902
2903         from_access = mask & MAY_ACCESS;
2904         mask &= (MAY_READ|MAY_WRITE|MAY_EXEC|MAY_APPEND);
2905
2906         /* No permission to check.  Existence test. */
2907         if (!mask)
2908                 return 0;
2909
2910         validate_creds(cred);
2911
2912         if (unlikely(IS_PRIVATE(inode)))
2913                 return 0;
2914
2915         perms = file_mask_to_av(inode->i_mode, mask);
2916
2917         sid = cred_sid(cred);
2918         isec = inode->i_security;
2919
2920         rc = avc_has_perm_noaudit(sid, isec->sid, isec->sclass, perms, 0, &avd);
2921         audited = avc_audit_required(perms, &avd, rc,
2922                                      from_access ? FILE__AUDIT_ACCESS : 0,
2923                                      &denied);
2924         if (likely(!audited))
2925                 return rc;
2926
2927         rc2 = audit_inode_permission(inode, perms, audited, denied, rc, flags);
2928         if (rc2)
2929                 return rc2;
2930         return rc;
2931 }
2932
2933 static int selinux_inode_setattr(struct dentry *dentry, struct iattr *iattr)
2934 {
2935         const struct cred *cred = current_cred();
2936         unsigned int ia_valid = iattr->ia_valid;
2937         __u32 av = FILE__WRITE;
2938
2939         /* ATTR_FORCE is just used for ATTR_KILL_S[UG]ID. */
2940         if (ia_valid & ATTR_FORCE) {
2941                 ia_valid &= ~(ATTR_KILL_SUID | ATTR_KILL_SGID | ATTR_MODE |
2942                               ATTR_FORCE);
2943                 if (!ia_valid)
2944                         return 0;
2945         }
2946
2947         if (ia_valid & (ATTR_MODE | ATTR_UID | ATTR_GID |
2948                         ATTR_ATIME_SET | ATTR_MTIME_SET | ATTR_TIMES_SET))
2949                 return dentry_has_perm(cred, dentry, FILE__SETATTR);
2950
2951         if (selinux_policycap_openperm && (ia_valid & ATTR_SIZE))
2952                 av |= FILE__OPEN;
2953
2954         return dentry_has_perm(cred, dentry, av);
2955 }
2956
2957 static int selinux_inode_getattr(const struct path *path)
2958 {
2959         return path_has_perm(current_cred(), path, FILE__GETATTR);
2960 }
2961
2962 static int selinux_inode_setotherxattr(struct dentry *dentry, const char *name)
2963 {
2964         const struct cred *cred = current_cred();
2965
2966         if (!strncmp(name, XATTR_SECURITY_PREFIX,
2967                      sizeof XATTR_SECURITY_PREFIX - 1)) {
2968                 if (!strcmp(name, XATTR_NAME_CAPS)) {
2969                         if (!capable(CAP_SETFCAP))
2970                                 return -EPERM;
2971                 } else if (!capable(CAP_SYS_ADMIN)) {
2972                         /* A different attribute in the security namespace.
2973                            Restrict to administrator. */
2974                         return -EPERM;
2975                 }
2976         }
2977
2978         /* Not an attribute we recognize, so just check the
2979            ordinary setattr permission. */
2980         return dentry_has_perm(cred, dentry, FILE__SETATTR);
2981 }
2982
2983 static int selinux_inode_setxattr(struct dentry *dentry, const char *name,
2984                                   const void *value, size_t size, int flags)
2985 {
2986         struct inode *inode = d_backing_inode(dentry);
2987         struct inode_security_struct *isec = inode->i_security;
2988         struct superblock_security_struct *sbsec;
2989         struct common_audit_data ad;
2990         u32 newsid, sid = current_sid();
2991         int rc = 0;
2992
2993         if (strcmp(name, XATTR_NAME_SELINUX))
2994                 return selinux_inode_setotherxattr(dentry, name);
2995
2996         sbsec = inode->i_sb->s_security;
2997         if (!(sbsec->flags & SBLABEL_MNT))
2998                 return -EOPNOTSUPP;
2999
3000         if (!inode_owner_or_capable(inode))
3001                 return -EPERM;
3002
3003         ad.type = LSM_AUDIT_DATA_DENTRY;
3004         ad.u.dentry = dentry;
3005
3006         rc = avc_has_perm(sid, isec->sid, isec->sclass,
3007                           FILE__RELABELFROM, &ad);
3008         if (rc)
3009                 return rc;
3010
3011         rc = security_context_to_sid(value, size, &newsid, GFP_KERNEL);
3012         if (rc == -EINVAL) {
3013                 if (!capable(CAP_MAC_ADMIN)) {
3014                         struct audit_buffer *ab;
3015                         size_t audit_size;
3016                         const char *str;
3017
3018                         /* We strip a nul only if it is at the end, otherwise the
3019                          * context contains a nul and we should audit that */
3020                         if (value) {
3021                                 str = value;
3022                                 if (str[size - 1] == '\0')
3023                                         audit_size = size - 1;
3024                                 else
3025                                         audit_size = size;
3026                         } else {
3027                                 str = "";
3028                                 audit_size = 0;
3029                         }
3030                         ab = audit_log_start(current->audit_context, GFP_ATOMIC, AUDIT_SELINUX_ERR);
3031                         audit_log_format(ab, "op=setxattr invalid_context=");
3032                         audit_log_n_untrustedstring(ab, value, audit_size);
3033                         audit_log_end(ab);
3034
3035                         return rc;
3036                 }
3037                 rc = security_context_to_sid_force(value, size, &newsid);
3038         }
3039         if (rc)
3040                 return rc;
3041
3042         rc = avc_has_perm(sid, newsid, isec->sclass,
3043                           FILE__RELABELTO, &ad);
3044         if (rc)
3045                 return rc;
3046
3047         rc = security_validate_transition(isec->sid, newsid, sid,
3048                                           isec->sclass);
3049         if (rc)
3050                 return rc;
3051
3052         return avc_has_perm(newsid,
3053                             sbsec->sid,
3054                             SECCLASS_FILESYSTEM,
3055                             FILESYSTEM__ASSOCIATE,
3056                             &ad);
3057 }
3058
3059 static void selinux_inode_post_setxattr(struct dentry *dentry, const char *name,
3060                                         const void *value, size_t size,
3061                                         int flags)
3062 {
3063         struct inode *inode = d_backing_inode(dentry);
3064         struct inode_security_struct *isec = inode->i_security;
3065         u32 newsid;
3066         int rc;
3067
3068         if (strcmp(name, XATTR_NAME_SELINUX)) {
3069                 /* Not an attribute we recognize, so nothing to do. */
3070                 return;
3071         }
3072
3073         rc = security_context_to_sid_force(value, size, &newsid);
3074         if (rc) {
3075                 printk(KERN_ERR "SELinux:  unable to map context to SID"
3076                        "for (%s, %lu), rc=%d\n",
3077                        inode->i_sb->s_id, inode->i_ino, -rc);
3078                 return;
3079         }
3080
3081         isec->sclass = inode_mode_to_security_class(inode->i_mode);
3082         isec->sid = newsid;
3083         isec->initialized = 1;
3084
3085         return;
3086 }
3087
3088 static int selinux_inode_getxattr(struct dentry *dentry, const char *name)
3089 {
3090         const struct cred *cred = current_cred();
3091
3092         return dentry_has_perm(cred, dentry, FILE__GETATTR);
3093 }
3094
3095 static int selinux_inode_listxattr(struct dentry *dentry)
3096 {
3097         const struct cred *cred = current_cred();
3098
3099         return dentry_has_perm(cred, dentry, FILE__GETATTR);
3100 }
3101
3102 static int selinux_inode_removexattr(struct dentry *dentry, const char *name)
3103 {
3104         if (strcmp(name, XATTR_NAME_SELINUX))
3105                 return selinux_inode_setotherxattr(dentry, name);
3106
3107         /* No one is allowed to remove a SELinux security label.
3108            You can change the label, but all data must be labeled. */
3109         return -EACCES;
3110 }
3111
3112 /*
3113  * Copy the inode security context value to the user.
3114  *
3115  * Permission check is handled by selinux_inode_getxattr hook.
3116  */
3117 static int selinux_inode_getsecurity(const struct inode *inode, const char *name, void **buffer, bool alloc)
3118 {
3119         u32 size;
3120         int error;
3121         char *context = NULL;
3122         struct inode_security_struct *isec = inode->i_security;
3123
3124         if (strcmp(name, XATTR_SELINUX_SUFFIX))
3125                 return -EOPNOTSUPP;
3126
3127         /*
3128          * If the caller has CAP_MAC_ADMIN, then get the raw context
3129          * value even if it is not defined by current policy; otherwise,
3130          * use the in-core value under current policy.
3131          * Use the non-auditing forms of the permission checks since
3132          * getxattr may be called by unprivileged processes commonly
3133          * and lack of permission just means that we fall back to the
3134          * in-core context value, not a denial.
3135          */
3136         error = selinux_capable(current_cred(), &init_user_ns, CAP_MAC_ADMIN,
3137                                 SECURITY_CAP_NOAUDIT);
3138         if (!error)
3139                 error = security_sid_to_context_force(isec->sid, &context,
3140                                                       &size);
3141         else
3142                 error = security_sid_to_context(isec->sid, &context, &size);
3143         if (error)
3144                 return error;
3145         error = size;
3146         if (alloc) {
3147                 *buffer = context;
3148                 goto out_nofree;
3149         }
3150         kfree(context);
3151 out_nofree:
3152         return error;
3153 }
3154
3155 static int selinux_inode_setsecurity(struct inode *inode, const char *name,
3156                                      const void *value, size_t size, int flags)
3157 {
3158         struct inode_security_struct *isec = inode->i_security;
3159         u32 newsid;
3160         int rc;
3161
3162         if (strcmp(name, XATTR_SELINUX_SUFFIX))
3163                 return -EOPNOTSUPP;
3164
3165         if (!value || !size)
3166                 return -EACCES;
3167
3168         rc = security_context_to_sid((void *)value, size, &newsid, GFP_KERNEL);
3169         if (rc)
3170                 return rc;
3171
3172         isec->sclass = inode_mode_to_security_class(inode->i_mode);
3173         isec->sid = newsid;
3174         isec->initialized = 1;
3175         return 0;
3176 }
3177
3178 static int selinux_inode_listsecurity(struct inode *inode, char *buffer, size_t buffer_size)
3179 {
3180         const int len = sizeof(XATTR_NAME_SELINUX);
3181         if (buffer && len <= buffer_size)
3182                 memcpy(buffer, XATTR_NAME_SELINUX, len);
3183         return len;
3184 }
3185
3186 static void selinux_inode_getsecid(const struct inode *inode, u32 *secid)
3187 {
3188         struct inode_security_struct *isec = inode->i_security;
3189         *secid = isec->sid;
3190 }
3191
3192 /* file security operations */
3193
3194 static int selinux_revalidate_file_permission(struct file *file, int mask)
3195 {
3196         const struct cred *cred = current_cred();
3197         struct inode *inode = file_inode(file);
3198
3199         /* file_mask_to_av won't add FILE__WRITE if MAY_APPEND is set */
3200         if ((file->f_flags & O_APPEND) && (mask & MAY_WRITE))
3201                 mask |= MAY_APPEND;
3202
3203         return file_has_perm(cred, file,
3204                              file_mask_to_av(inode->i_mode, mask));
3205 }
3206
3207 static int selinux_file_permission(struct file *file, int mask)
3208 {
3209         struct inode *inode = file_inode(file);
3210         struct file_security_struct *fsec = file->f_security;
3211         struct inode_security_struct *isec = inode->i_security;
3212         u32 sid = current_sid();
3213
3214         if (!mask)
3215                 /* No permission to check.  Existence test. */
3216                 return 0;
3217
3218         if (sid == fsec->sid && fsec->isid == isec->sid &&
3219             fsec->pseqno == avc_policy_seqno())
3220                 /* No change since file_open check. */
3221                 return 0;
3222
3223         return selinux_revalidate_file_permission(file, mask);
3224 }
3225
3226 static int selinux_file_alloc_security(struct file *file)
3227 {
3228         return file_alloc_security(file);
3229 }
3230
3231 static void selinux_file_free_security(struct file *file)
3232 {
3233         file_free_security(file);
3234 }
3235
3236 static int selinux_file_ioctl(struct file *file, unsigned int cmd,
3237                               unsigned long arg)
3238 {
3239         const struct cred *cred = current_cred();
3240         int error = 0;
3241
3242         switch (cmd) {
3243         case FIONREAD:
3244         /* fall through */
3245         case FIBMAP:
3246         /* fall through */
3247         case FIGETBSZ:
3248         /* fall through */
3249         case FS_IOC_GETFLAGS:
3250         /* fall through */
3251         case FS_IOC_GETVERSION:
3252                 error = file_has_perm(cred, file, FILE__GETATTR);
3253                 break;
3254
3255         case FS_IOC_SETFLAGS:
3256         /* fall through */
3257         case FS_IOC_SETVERSION:
3258                 error = file_has_perm(cred, file, FILE__SETATTR);
3259                 break;
3260
3261         /* sys_ioctl() checks */
3262         case FIONBIO:
3263         /* fall through */
3264         case FIOASYNC:
3265                 error = file_has_perm(cred, file, 0);
3266                 break;
3267
3268         case KDSKBENT:
3269         case KDSKBSENT:
3270                 error = cred_has_capability(cred, CAP_SYS_TTY_CONFIG,
3271                                             SECURITY_CAP_AUDIT);
3272                 break;
3273
3274         /* default case assumes that the command will go
3275          * to the file's ioctl() function.
3276          */
3277         default:
3278                 error = file_has_perm(cred, file, FILE__IOCTL);
3279         }
3280         return error;
3281 }
3282
3283 static int default_noexec;
3284
3285 static int file_map_prot_check(struct file *file, unsigned long prot, int shared)
3286 {
3287         const struct cred *cred = current_cred();
3288         int rc = 0;
3289
3290         if (default_noexec &&
3291             (prot & PROT_EXEC) && (!file || IS_PRIVATE(file_inode(file)) ||
3292                                    (!shared && (prot & PROT_WRITE)))) {
3293                 /*
3294                  * We are making executable an anonymous mapping or a
3295                  * private file mapping that will also be writable.
3296                  * This has an additional check.
3297                  */
3298                 rc = cred_has_perm(cred, cred, PROCESS__EXECMEM);
3299                 if (rc)
3300                         goto error;
3301         }
3302
3303         if (file) {
3304                 /* read access is always possible with a mapping */
3305                 u32 av = FILE__READ;
3306
3307                 /* write access only matters if the mapping is shared */
3308                 if (shared && (prot & PROT_WRITE))
3309                         av |= FILE__WRITE;
3310
3311                 if (prot & PROT_EXEC)
3312                         av |= FILE__EXECUTE;
3313
3314                 return file_has_perm(cred, file, av);
3315         }
3316
3317 error:
3318         return rc;
3319 }
3320
3321 static int selinux_mmap_addr(unsigned long addr)
3322 {
3323         int rc;
3324
3325         /* do DAC check on address space usage */
3326         rc = cap_mmap_addr(addr);
3327         if (rc)
3328                 return rc;
3329
3330         if (addr < CONFIG_LSM_MMAP_MIN_ADDR) {
3331                 u32 sid = current_sid();
3332                 rc = avc_has_perm(sid, sid, SECCLASS_MEMPROTECT,
3333                                   MEMPROTECT__MMAP_ZERO, NULL);
3334         }
3335
3336         return rc;
3337 }
3338
3339 static int selinux_mmap_file(struct file *file, unsigned long reqprot,
3340                              unsigned long prot, unsigned long flags)
3341 {
3342         if (selinux_checkreqprot)
3343                 prot = reqprot;
3344
3345         return file_map_prot_check(file, prot,
3346                                    (flags & MAP_TYPE) == MAP_SHARED);
3347 }
3348
3349 static int selinux_file_mprotect(struct vm_area_struct *vma,
3350                                  unsigned long reqprot,
3351                                  unsigned long prot)
3352 {
3353         const struct cred *cred = current_cred();
3354
3355         if (selinux_checkreqprot)
3356                 prot = reqprot;
3357
3358         if (default_noexec &&
3359             (prot & PROT_EXEC) && !(vma->vm_flags & VM_EXEC)) {
3360                 int rc = 0;
3361                 if (vma->vm_start >= vma->vm_mm->start_brk &&
3362                     vma->vm_end <= vma->vm_mm->brk) {
3363                         rc = cred_has_perm(cred, cred, PROCESS__EXECHEAP);
3364                 } else if (!vma->vm_file &&
3365                            vma->vm_start <= vma->vm_mm->start_stack &&
3366                            vma->vm_end >= vma->vm_mm->start_stack) {
3367                         rc = current_has_perm(current, PROCESS__EXECSTACK);
3368                 } else if (vma->vm_file && vma->anon_vma) {
3369                         /*
3370                          * We are making executable a file mapping that has
3371                          * had some COW done. Since pages might have been
3372                          * written, check ability to execute the possibly
3373                          * modified content.  This typically should only
3374                          * occur for text relocations.
3375                          */
3376                         rc = file_has_perm(cred, vma->vm_file, FILE__EXECMOD);
3377                 }
3378                 if (rc)
3379                         return rc;
3380         }
3381
3382         return file_map_prot_check(vma->vm_file, prot, vma->vm_flags&VM_SHARED);
3383 }
3384
3385 static int selinux_file_lock(struct file *file, unsigned int cmd)
3386 {
3387         const struct cred *cred = current_cred();
3388
3389         return file_has_perm(cred, file, FILE__LOCK);
3390 }
3391
3392 static int selinux_file_fcntl(struct file *file, unsigned int cmd,
3393                               unsigned long arg)
3394 {
3395         const struct cred *cred = current_cred();
3396         int err = 0;
3397
3398         switch (cmd) {
3399         case F_SETFL:
3400                 if ((file->f_flags & O_APPEND) && !(arg & O_APPEND)) {
3401                         err = file_has_perm(cred, file, FILE__WRITE);
3402                         break;
3403                 }
3404                 /* fall through */
3405         case F_SETOWN:
3406         case F_SETSIG:
3407         case F_GETFL:
3408         case F_GETOWN:
3409         case F_GETSIG:
3410         case F_GETOWNER_UIDS:
3411                 /* Just check FD__USE permission */
3412                 err = file_has_perm(cred, file, 0);
3413                 break;
3414         case F_GETLK:
3415         case F_SETLK:
3416         case F_SETLKW:
3417         case F_OFD_GETLK:
3418         case F_OFD_SETLK:
3419         case F_OFD_SETLKW:
3420 #if BITS_PER_LONG == 32
3421         case F_GETLK64:
3422         case F_SETLK64:
3423         case F_SETLKW64:
3424 #endif
3425                 err = file_has_perm(cred, file, FILE__LOCK);
3426                 break;
3427         }
3428
3429         return err;
3430 }
3431
3432 static void selinux_file_set_fowner(struct file *file)
3433 {
3434         struct file_security_struct *fsec;
3435
3436         fsec = file->f_security;
3437         fsec->fown_sid = current_sid();
3438 }
3439
3440 static int selinux_file_send_sigiotask(struct task_struct *tsk,
3441                                        struct fown_struct *fown, int signum)
3442 {
3443         struct file *file;
3444         u32 sid = task_sid(tsk);
3445         u32 perm;
3446         struct file_security_struct *fsec;
3447
3448         /* struct fown_struct is never outside the context of a struct file */
3449         file = container_of(fown, struct file, f_owner);
3450
3451         fsec = file->f_security;
3452
3453         if (!signum)
3454                 perm = signal_to_av(SIGIO); /* as per send_sigio_to_task */
3455         else
3456                 perm = signal_to_av(signum);
3457
3458         return avc_has_perm(fsec->fown_sid, sid,
3459                             SECCLASS_PROCESS, perm, NULL);
3460 }
3461
3462 static int selinux_file_receive(struct file *file)
3463 {
3464         const struct cred *cred = current_cred();
3465
3466         return file_has_perm(cred, file, file_to_av(file));
3467 }
3468
3469 static int selinux_file_open(struct file *file, const struct cred *cred)
3470 {
3471         struct file_security_struct *fsec;
3472         struct inode_security_struct *isec;
3473
3474         fsec = file->f_security;
3475         isec = file_inode(file)->i_security;
3476         /*
3477          * Save inode label and policy sequence number
3478          * at open-time so that selinux_file_permission
3479          * can determine whether revalidation is necessary.
3480          * Task label is already saved in the file security
3481          * struct as its SID.
3482          */
3483         fsec->isid = isec->sid;
3484         fsec->pseqno = avc_policy_seqno();
3485         /*
3486          * Since the inode label or policy seqno may have changed
3487          * between the selinux_inode_permission check and the saving
3488          * of state above, recheck that access is still permitted.
3489          * Otherwise, access might never be revalidated against the
3490          * new inode label or new policy.
3491          * This check is not redundant - do not remove.
3492          */
3493         return file_path_has_perm(cred, file, open_file_to_av(file));
3494 }
3495
3496 /* task security operations */
3497
3498 static int selinux_task_create(unsigned long clone_flags)
3499 {
3500         return current_has_perm(current, PROCESS__FORK);
3501 }
3502
3503 /*
3504  * allocate the SELinux part of blank credentials
3505  */
3506 static int selinux_cred_alloc_blank(struct cred *cred, gfp_t gfp)
3507 {
3508         struct task_security_struct *tsec;
3509
3510         tsec = kzalloc(sizeof(struct task_security_struct), gfp);
3511         if (!tsec)
3512                 return -ENOMEM;
3513
3514         cred->security = tsec;
3515         return 0;
3516 }
3517
3518 /*
3519  * detach and free the LSM part of a set of credentials
3520  */
3521 static void selinux_cred_free(struct cred *cred)
3522 {
3523         struct task_security_struct *tsec = cred->security;
3524
3525         /*
3526          * cred->security == NULL if security_cred_alloc_blank() or
3527          * security_prepare_creds() returned an error.
3528          */
3529         BUG_ON(cred->security && (unsigned long) cred->security < PAGE_SIZE);
3530         cred->security = (void *) 0x7UL;
3531         kfree(tsec);
3532 }
3533
3534 /*
3535  * prepare a new set of credentials for modification
3536  */
3537 static int selinux_cred_prepare(struct cred *new, const struct cred *old,
3538                                 gfp_t gfp)
3539 {
3540         const struct task_security_struct *old_tsec;
3541         struct task_security_struct *tsec;
3542
3543         old_tsec = old->security;
3544
3545         tsec = kmemdup(old_tsec, sizeof(struct task_security_struct), gfp);
3546         if (!tsec)
3547                 return -ENOMEM;
3548
3549         new->security = tsec;
3550         return 0;
3551 }
3552
3553 /*
3554  * transfer the SELinux data to a blank set of creds
3555  */
3556 static void selinux_cred_transfer(struct cred *new, const struct cred *old)
3557 {
3558         const struct task_security_struct *old_tsec = old->security;
3559         struct task_security_struct *tsec = new->security;
3560
3561         *tsec = *old_tsec;
3562 }
3563
3564 /*
3565  * set the security data for a kernel service
3566  * - all the creation contexts are set to unlabelled
3567  */
3568 static int selinux_kernel_act_as(struct cred *new, u32 secid)
3569 {
3570         struct task_security_struct *tsec = new->security;
3571         u32 sid = current_sid();
3572         int ret;
3573
3574         ret = avc_has_perm(sid, secid,
3575                            SECCLASS_KERNEL_SERVICE,
3576                            KERNEL_SERVICE__USE_AS_OVERRIDE,
3577                            NULL);
3578         if (ret == 0) {
3579                 tsec->sid = secid;
3580                 tsec->create_sid = 0;
3581                 tsec->keycreate_sid = 0;
3582                 tsec->sockcreate_sid = 0;
3583         }
3584         return ret;
3585 }
3586
3587 /*
3588  * set the file creation context in a security record to the same as the
3589  * objective context of the specified inode
3590  */
3591 static int selinux_kernel_create_files_as(struct cred *new, struct inode *inode)
3592 {
3593         struct inode_security_struct *isec = inode->i_security;
3594         struct task_security_struct *tsec = new->security;
3595         u32 sid = current_sid();
3596         int ret;
3597
3598         ret = avc_has_perm(sid, isec->sid,
3599                            SECCLASS_KERNEL_SERVICE,
3600                            KERNEL_SERVICE__CREATE_FILES_AS,
3601                            NULL);
3602
3603         if (ret == 0)
3604                 tsec->create_sid = isec->sid;
3605         return ret;
3606 }
3607
3608 static int selinux_kernel_module_request(char *kmod_name)
3609 {
3610         u32 sid;
3611         struct common_audit_data ad;
3612
3613         sid = task_sid(current);
3614
3615         ad.type = LSM_AUDIT_DATA_KMOD;
3616         ad.u.kmod_name = kmod_name;
3617
3618         return avc_has_perm(sid, SECINITSID_KERNEL, SECCLASS_SYSTEM,
3619                             SYSTEM__MODULE_REQUEST, &ad);
3620 }
3621
3622 static int selinux_task_setpgid(struct task_struct *p, pid_t pgid)
3623 {
3624         return current_has_perm(p, PROCESS__SETPGID);
3625 }
3626
3627 static int selinux_task_getpgid(struct task_struct *p)
3628 {
3629         return current_has_perm(p, PROCESS__GETPGID);
3630 }
3631
3632 static int selinux_task_getsid(struct task_struct *p)
3633 {
3634         return current_has_perm(p, PROCESS__GETSESSION);
3635 }
3636
3637 static void selinux_task_getsecid(struct task_struct *p, u32 *secid)
3638 {
3639         *secid = task_sid(p);
3640 }
3641
3642 static int selinux_task_setnice(struct task_struct *p, int nice)
3643 {
3644         int rc;
3645
3646         rc = cap_task_setnice(p, nice);
3647         if (rc)
3648                 return rc;
3649
3650         return current_has_perm(p, PROCESS__SETSCHED);
3651 }
3652
3653 static int selinux_task_setioprio(struct task_struct *p, int ioprio)
3654 {
3655         int rc;
3656
3657         rc = cap_task_setioprio(p, ioprio);
3658         if (rc)
3659                 return rc;
3660
3661         return current_has_perm(p, PROCESS__SETSCHED);
3662 }
3663
3664 static int selinux_task_getioprio(struct task_struct *p)
3665 {
3666         return current_has_perm(p, PROCESS__GETSCHED);
3667 }
3668
3669 static int selinux_task_setrlimit(struct task_struct *p, unsigned int resource,
3670                 struct rlimit *new_rlim)
3671 {
3672         struct rlimit *old_rlim = p->signal->rlim + resource;
3673
3674         /* Control the ability to change the hard limit (whether
3675            lowering or raising it), so that the hard limit can
3676            later be used as a safe reset point for the soft limit
3677            upon context transitions.  See selinux_bprm_committing_creds. */
3678         if (old_rlim->rlim_max != new_rlim->rlim_max)
3679                 return current_has_perm(p, PROCESS__SETRLIMIT);
3680
3681         return 0;
3682 }
3683
3684 static int selinux_task_setscheduler(struct task_struct *p)
3685 {
3686         int rc;
3687
3688         rc = cap_task_setscheduler(p);
3689         if (rc)
3690                 return rc;
3691
3692         return current_has_perm(p, PROCESS__SETSCHED);
3693 }
3694
3695 static int selinux_task_getscheduler(struct task_struct *p)
3696 {
3697         return current_has_perm(p, PROCESS__GETSCHED);
3698 }
3699
3700 static int selinux_task_movememory(struct task_struct *p)
3701 {
3702         return current_has_perm(p, PROCESS__SETSCHED);
3703 }
3704
3705 static int selinux_task_kill(struct task_struct *p, struct siginfo *info,
3706                                 int sig, u32 secid)
3707 {
3708         u32 perm;
3709         int rc;
3710
3711         if (!sig)
3712                 perm = PROCESS__SIGNULL; /* null signal; existence test */
3713         else
3714                 perm = signal_to_av(sig);
3715         if (secid)
3716                 rc = avc_has_perm(secid, task_sid(p),
3717                                   SECCLASS_PROCESS, perm, NULL);
3718         else
3719                 rc = current_has_perm(p, perm);
3720         return rc;
3721 }
3722
3723 static int selinux_task_wait(struct task_struct *p)
3724 {
3725         return task_has_perm(p, current, PROCESS__SIGCHLD);
3726 }
3727
3728 static void selinux_task_to_inode(struct task_struct *p,
3729                                   struct inode *inode)
3730 {
3731         struct inode_security_struct *isec = inode->i_security;
3732         u32 sid = task_sid(p);
3733
3734         isec->sid = sid;
3735         isec->initialized = 1;
3736 }
3737
3738 /* Returns error only if unable to parse addresses */
3739 static int selinux_parse_skb_ipv4(struct sk_buff *skb,
3740                         struct common_audit_data *ad, u8 *proto)
3741 {
3742         int offset, ihlen, ret = -EINVAL;
3743         struct iphdr _iph, *ih;
3744
3745         offset = skb_network_offset(skb);
3746         ih = skb_header_pointer(skb, offset, sizeof(_iph), &_iph);
3747         if (ih == NULL)
3748                 goto out;
3749
3750         ihlen = ih->ihl * 4;
3751         if (ihlen < sizeof(_iph))
3752                 goto out;
3753
3754         ad->u.net->v4info.saddr = ih->saddr;
3755         ad->u.net->v4info.daddr = ih->daddr;
3756         ret = 0;
3757
3758         if (proto)
3759                 *proto = ih->protocol;
3760
3761         switch (ih->protocol) {
3762         case IPPROTO_TCP: {
3763                 struct tcphdr _tcph, *th;
3764
3765                 if (ntohs(ih->frag_off) & IP_OFFSET)
3766                         break;
3767
3768                 offset += ihlen;
3769                 th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph);
3770                 if (th == NULL)
3771                         break;
3772
3773                 ad->u.net->sport = th->source;
3774                 ad->u.net->dport = th->dest;
3775                 break;
3776         }
3777
3778         case IPPROTO_UDP: {
3779                 struct udphdr _udph, *uh;
3780
3781                 if (ntohs(ih->frag_off) & IP_OFFSET)
3782                         break;
3783
3784                 offset += ihlen;
3785                 uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph);
3786                 if (uh == NULL)
3787                         break;
3788
3789                 ad->u.net->sport = uh->source;
3790                 ad->u.net->dport = uh->dest;
3791                 break;
3792         }
3793
3794         case IPPROTO_DCCP: {
3795                 struct dccp_hdr _dccph, *dh;
3796
3797                 if (ntohs(ih->frag_off) & IP_OFFSET)
3798                         break;
3799
3800                 offset += ihlen;
3801                 dh = skb_header_pointer(skb, offset, sizeof(_dccph), &_dccph);
3802                 if (dh == NULL)
3803                         break;
3804
3805                 ad->u.net->sport = dh->dccph_sport;
3806                 ad->u.net->dport = dh->dccph_dport;
3807                 break;
3808         }
3809
3810         default:
3811                 break;
3812         }
3813 out:
3814         return ret;
3815 }
3816
3817 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
3818
3819 /* Returns error only if unable to parse addresses */
3820 static int selinux_parse_skb_ipv6(struct sk_buff *skb,
3821                         struct common_audit_data *ad, u8 *proto)
3822 {
3823         u8 nexthdr;
3824         int ret = -EINVAL, offset;
3825         struct ipv6hdr _ipv6h, *ip6;
3826         __be16 frag_off;
3827
3828         offset = skb_network_offset(skb);
3829         ip6 = skb_header_pointer(skb, offset, sizeof(_ipv6h), &_ipv6h);
3830         if (ip6 == NULL)
3831                 goto out;
3832
3833         ad->u.net->v6info.saddr = ip6->saddr;
3834         ad->u.net->v6info.daddr = ip6->daddr;
3835         ret = 0;
3836
3837         nexthdr = ip6->nexthdr;
3838         offset += sizeof(_ipv6h);
3839         offset = ipv6_skip_exthdr(skb, offset, &nexthdr, &frag_off);
3840         if (offset < 0)
3841                 goto out;
3842
3843         if (proto)
3844                 *proto = nexthdr;
3845
3846         switch (nexthdr) {
3847         case IPPROTO_TCP: {
3848                 struct tcphdr _tcph, *th;
3849
3850                 th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph);
3851                 if (th == NULL)
3852                         break;
3853
3854                 ad->u.net->sport = th->source;
3855                 ad->u.net->dport = th->dest;
3856                 break;
3857         }
3858
3859         case IPPROTO_UDP: {
3860                 struct udphdr _udph, *uh;
3861
3862                 uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph);
3863                 if (uh == NULL)
3864                         break;
3865
3866                 ad->u.net->sport = uh->source;
3867                 ad->u.net->dport = uh->dest;
3868                 break;
3869         }
3870
3871         case IPPROTO_DCCP: {
3872                 struct dccp_hdr _dccph, *dh;
3873
3874                 dh = skb_header_pointer(skb, offset, sizeof(_dccph), &_dccph);
3875                 if (dh == NULL)
3876                         break;
3877
3878                 ad->u.net->sport = dh->dccph_sport;
3879                 ad->u.net->dport = dh->dccph_dport;
3880                 break;
3881         }
3882
3883         /* includes fragments */
3884         default:
3885                 break;
3886         }
3887 out:
3888         return ret;
3889 }
3890
3891 #endif /* IPV6 */
3892
3893 static int selinux_parse_skb(struct sk_buff *skb, struct common_audit_data *ad,
3894                              char **_addrp, int src, u8 *proto)
3895 {
3896         char *addrp;
3897         int ret;
3898
3899         switch (ad->u.net->family) {
3900         case PF_INET:
3901                 ret = selinux_parse_skb_ipv4(skb, ad, proto);
3902                 if (ret)
3903                         goto parse_error;
3904                 addrp = (char *)(src ? &ad->u.net->v4info.saddr :
3905                                        &ad->u.net->v4info.daddr);
3906                 goto okay;
3907
3908 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
3909         case PF_INET6:
3910                 ret = selinux_parse_skb_ipv6(skb, ad, proto);
3911                 if (ret)
3912                         goto parse_error;
3913                 addrp = (char *)(src ? &ad->u.net->v6info.saddr :
3914                                        &ad->u.net->v6info.daddr);
3915                 goto okay;
3916 #endif  /* IPV6 */
3917         default:
3918                 addrp = NULL;
3919                 goto okay;
3920         }
3921
3922 parse_error:
3923         printk(KERN_WARNING
3924                "SELinux: failure in selinux_parse_skb(),"
3925                " unable to parse packet\n");
3926         return ret;
3927
3928 okay:
3929         if (_addrp)
3930                 *_addrp = addrp;
3931         return 0;
3932 }
3933
3934 /**
3935  * selinux_skb_peerlbl_sid - Determine the peer label of a packet
3936  * @skb: the packet
3937  * @family: protocol family
3938  * @sid: the packet's peer label SID
3939  *
3940  * Description:
3941  * Check the various different forms of network peer labeling and determine
3942  * the peer label/SID for the packet; most of the magic actually occurs in
3943  * the security server function security_net_peersid_cmp().  The function
3944  * returns zero if the value in @sid is valid (although it may be SECSID_NULL)
3945  * or -EACCES if @sid is invalid due to inconsistencies with the different
3946  * peer labels.
3947  *
3948  */
3949 static int selinux_skb_peerlbl_sid(struct sk_buff *skb, u16 family, u32 *sid)
3950 {
3951         int err;
3952         u32 xfrm_sid;
3953         u32 nlbl_sid;
3954         u32 nlbl_type;
3955
3956         err = selinux_xfrm_skb_sid(skb, &xfrm_sid);
3957         if (unlikely(err))
3958                 return -EACCES;
3959         err = selinux_netlbl_skbuff_getsid(skb, family, &nlbl_type, &nlbl_sid);
3960         if (unlikely(err))
3961                 return -EACCES;
3962
3963         err = security_net_peersid_resolve(nlbl_sid, nlbl_type, xfrm_sid, sid);
3964         if (unlikely(err)) {
3965                 printk(KERN_WARNING
3966                        "SELinux: failure in selinux_skb_peerlbl_sid(),"
3967                        " unable to determine packet's peer label\n");
3968                 return -EACCES;
3969         }
3970
3971         return 0;
3972 }
3973
3974 /**
3975  * selinux_conn_sid - Determine the child socket label for a connection
3976  * @sk_sid: the parent socket's SID
3977  * @skb_sid: the packet's SID
3978  * @conn_sid: the resulting connection SID
3979  *
3980  * If @skb_sid is valid then the user:role:type information from @sk_sid is
3981  * combined with the MLS information from @skb_sid in order to create
3982  * @conn_sid.  If @skb_sid is not valid then then @conn_sid is simply a copy
3983  * of @sk_sid.  Returns zero on success, negative values on failure.
3984  *
3985  */
3986 static int selinux_conn_sid(u32 sk_sid, u32 skb_sid, u32 *conn_sid)
3987 {
3988         int err = 0;
3989
3990         if (skb_sid != SECSID_NULL)
3991                 err = security_sid_mls_copy(sk_sid, skb_sid, conn_sid);
3992         else
3993                 *conn_sid = sk_sid;
3994
3995         return err;
3996 }
3997
3998 /* socket security operations */
3999
4000 static int socket_sockcreate_sid(const struct task_security_struct *tsec,
4001                                  u16 secclass, u32 *socksid)
4002 {
4003         if (tsec->sockcreate_sid > SECSID_NULL) {
4004                 *socksid = tsec->sockcreate_sid;
4005                 return 0;
4006         }
4007
4008         return security_transition_sid(tsec->sid, tsec->sid, secclass, NULL,
4009                                        socksid);
4010 }
4011
4012 static int sock_has_perm(struct task_struct *task, struct sock *sk, u32 perms)
4013 {
4014         struct sk_security_struct *sksec = sk->sk_security;
4015         struct common_audit_data ad;
4016         struct lsm_network_audit net = {0,};
4017         u32 tsid = task_sid(task);
4018
4019         if (sksec->sid == SECINITSID_KERNEL)
4020                 return 0;
4021
4022         ad.type = LSM_AUDIT_DATA_NET;
4023         ad.u.net = &net;
4024         ad.u.net->sk = sk;
4025
4026         return avc_has_perm(tsid, sksec->sid, sksec->sclass, perms, &ad);
4027 }
4028
4029 static int selinux_socket_create(int family, int type,
4030                                  int protocol, int kern)
4031 {
4032         const struct task_security_struct *tsec = current_security();
4033         u32 newsid;
4034         u16 secclass;
4035         int rc;
4036
4037         if (kern)
4038                 return 0;
4039
4040         secclass = socket_type_to_security_class(family, type, protocol);
4041         rc = socket_sockcreate_sid(tsec, secclass, &newsid);
4042         if (rc)
4043                 return rc;
4044
4045         return avc_has_perm(tsec->sid, newsid, secclass, SOCKET__CREATE, NULL);
4046 }
4047
4048 static int selinux_socket_post_create(struct socket *sock, int family,
4049                                       int type, int protocol, int kern)
4050 {
4051         const struct task_security_struct *tsec = current_security();
4052         struct inode_security_struct *isec = SOCK_INODE(sock)->i_security;
4053         struct sk_security_struct *sksec;
4054         int err = 0;
4055
4056         isec->sclass = socket_type_to_security_class(family, type, protocol);
4057
4058         if (kern)
4059                 isec->sid = SECINITSID_KERNEL;
4060         else {
4061                 err = socket_sockcreate_sid(tsec, isec->sclass, &(isec->sid));
4062                 if (err)
4063                         return err;
4064         }
4065
4066         isec->initialized = 1;
4067
4068         if (sock->sk) {
4069                 sksec = sock->sk->sk_security;
4070                 sksec->sid = isec->sid;
4071                 sksec->sclass = isec->sclass;
4072                 err = selinux_netlbl_socket_post_create(sock->sk, family);
4073         }
4074
4075         return err;
4076 }
4077
4078 /* Range of port numbers used to automatically bind.
4079    Need to determine whether we should perform a name_bind
4080    permission check between the socket and the port number. */
4081
4082 static int selinux_socket_bind(struct socket *sock, struct sockaddr *address, int addrlen)
4083 {
4084         struct sock *sk = sock->sk;
4085         u16 family;
4086         int err;
4087
4088         err = sock_has_perm(current, sk, SOCKET__BIND);
4089         if (err)
4090                 goto out;
4091
4092         /*
4093          * If PF_INET or PF_INET6, check name_bind permission for the port.
4094          * Multiple address binding for SCTP is not supported yet: we just
4095          * check the first address now.
4096          */
4097         family = sk->sk_family;
4098         if (family == PF_INET || family == PF_INET6) {
4099                 char *addrp;
4100                 struct sk_security_struct *sksec = sk->sk_security;
4101                 struct common_audit_data ad;
4102                 struct lsm_network_audit net = {0,};
4103                 struct sockaddr_in *addr4 = NULL;
4104                 struct sockaddr_in6 *addr6 = NULL;
4105                 unsigned short snum;
4106                 u32 sid, node_perm;
4107
4108                 if (family == PF_INET) {
4109                         addr4 = (struct sockaddr_in *)address;
4110                         snum = ntohs(addr4->sin_port);
4111                         addrp = (char *)&addr4->sin_addr.s_addr;
4112                 } else {
4113                         addr6 = (struct sockaddr_in6 *)address;
4114                         snum = ntohs(addr6->sin6_port);
4115                         addrp = (char *)&addr6->sin6_addr.s6_addr;
4116                 }
4117
4118                 if (snum) {
4119                         int low, high;
4120
4121                         inet_get_local_port_range(sock_net(sk), &low, &high);
4122
4123                         if (snum < max(PROT_SOCK, low) || snum > high) {
4124                                 err = sel_netport_sid(sk->sk_protocol,
4125                                                       snum, &sid);
4126                                 if (err)
4127                                         goto out;
4128                                 ad.type = LSM_AUDIT_DATA_NET;
4129                                 ad.u.net = &net;
4130                                 ad.u.net->sport = htons(snum);
4131                                 ad.u.net->family = family;
4132                                 err = avc_has_perm(sksec->sid, sid,
4133                                                    sksec->sclass,
4134                                                    SOCKET__NAME_BIND, &ad);
4135                                 if (err)
4136                                         goto out;
4137                         }
4138                 }
4139
4140                 switch (sksec->sclass) {
4141                 case SECCLASS_TCP_SOCKET:
4142                         node_perm = TCP_SOCKET__NODE_BIND;
4143                         break;
4144
4145                 case SECCLASS_UDP_SOCKET:
4146                         node_perm = UDP_SOCKET__NODE_BIND;
4147                         break;
4148
4149                 case SECCLASS_DCCP_SOCKET:
4150                         node_perm = DCCP_SOCKET__NODE_BIND;
4151                         break;
4152
4153                 default:
4154                         node_perm = RAWIP_SOCKET__NODE_BIND;
4155                         break;
4156                 }
4157
4158                 err = sel_netnode_sid(addrp, family, &sid);
4159                 if (err)
4160                         goto out;
4161
4162                 ad.type = LSM_AUDIT_DATA_NET;
4163                 ad.u.net = &net;
4164                 ad.u.net->sport = htons(snum);
4165                 ad.u.net->family = family;
4166
4167                 if (family == PF_INET)
4168                         ad.u.net->v4info.saddr = addr4->sin_addr.s_addr;
4169                 else
4170                         ad.u.net->v6info.saddr = addr6->sin6_addr;
4171
4172                 err = avc_has_perm(sksec->sid, sid,
4173                                    sksec->sclass, node_perm, &ad);
4174                 if (err)
4175                         goto out;
4176         }
4177 out:
4178         return err;
4179 }
4180
4181 static int selinux_socket_connect(struct socket *sock, struct sockaddr *address, int addrlen)
4182 {
4183         struct sock *sk = sock->sk;
4184         struct sk_security_struct *sksec = sk->sk_security;
4185         int err;
4186
4187         err = sock_has_perm(current, sk, SOCKET__CONNECT);
4188         if (err)
4189                 return err;
4190
4191         /*
4192          * If a TCP or DCCP socket, check name_connect permission for the port.
4193          */
4194         if (sksec->sclass == SECCLASS_TCP_SOCKET ||
4195             sksec->sclass == SECCLASS_DCCP_SOCKET) {
4196                 struct common_audit_data ad;
4197                 struct lsm_network_audit net = {0,};
4198                 struct sockaddr_in *addr4 = NULL;
4199                 struct sockaddr_in6 *addr6 = NULL;
4200                 unsigned short snum;
4201                 u32 sid, perm;
4202
4203                 if (sk->sk_family == PF_INET) {
4204                         addr4 = (struct sockaddr_in *)address;
4205                         if (addrlen < sizeof(struct sockaddr_in))
4206                                 return -EINVAL;
4207                         snum = ntohs(addr4->sin_port);
4208                 } else {
4209                         addr6 = (struct sockaddr_in6 *)address;
4210                         if (addrlen < SIN6_LEN_RFC2133)
4211                                 return -EINVAL;
4212                         snum = ntohs(addr6->sin6_port);
4213                 }
4214
4215                 err = sel_netport_sid(sk->sk_protocol, snum, &sid);
4216                 if (err)
4217                         goto out;
4218
4219                 perm = (sksec->sclass == SECCLASS_TCP_SOCKET) ?
4220                        TCP_SOCKET__NAME_CONNECT : DCCP_SOCKET__NAME_CONNECT;
4221
4222                 ad.type = LSM_AUDIT_DATA_NET;
4223                 ad.u.net = &net;
4224                 ad.u.net->dport = htons(snum);
4225                 ad.u.net->family = sk->sk_family;
4226                 err = avc_has_perm(sksec->sid, sid, sksec->sclass, perm, &ad);
4227                 if (err)
4228                         goto out;
4229         }
4230
4231         err = selinux_netlbl_socket_connect(sk, address);
4232
4233 out:
4234         return err;
4235 }
4236
4237 static int selinux_socket_listen(struct socket *sock, int backlog)
4238 {
4239         return sock_has_perm(current, sock->sk, SOCKET__LISTEN);
4240 }
4241
4242 static int selinux_socket_accept(struct socket *sock, struct socket *newsock)
4243 {
4244         int err;
4245         struct inode_security_struct *isec;
4246         struct inode_security_struct *newisec;
4247
4248         err = sock_has_perm(current, sock->sk, SOCKET__ACCEPT);
4249         if (err)
4250                 return err;
4251
4252         newisec = SOCK_INODE(newsock)->i_security;
4253
4254         isec = SOCK_INODE(sock)->i_security;
4255         newisec->sclass = isec->sclass;
4256         newisec->sid = isec->sid;
4257         newisec->initialized = 1;
4258
4259         return 0;
4260 }
4261
4262 static int selinux_socket_sendmsg(struct socket *sock, struct msghdr *msg,
4263                                   int size)
4264 {
4265         return sock_has_perm(current, sock->sk, SOCKET__WRITE);
4266 }
4267
4268 static int selinux_socket_recvmsg(struct socket *sock, struct msghdr *msg,
4269                                   int size, int flags)
4270 {
4271         return sock_has_perm(current, sock->sk, SOCKET__READ);
4272 }
4273
4274 static int selinux_socket_getsockname(struct socket *sock)
4275 {
4276         return sock_has_perm(current, sock->sk, SOCKET__GETATTR);
4277 }
4278
4279 static int selinux_socket_getpeername(struct socket *sock)
4280 {
4281         return sock_has_perm(current, sock->sk, SOCKET__GETATTR);
4282 }
4283
4284 static int selinux_socket_setsockopt(struct socket *sock, int level, int optname)
4285 {
4286         int err;
4287
4288         err = sock_has_perm(current, sock->sk, SOCKET__SETOPT);
4289         if (err)
4290                 return err;
4291
4292         return selinux_netlbl_socket_setsockopt(sock, level, optname);
4293 }
4294
4295 static int selinux_socket_getsockopt(struct socket *sock, int level,
4296                                      int optname)
4297 {
4298         return sock_has_perm(current, sock->sk, SOCKET__GETOPT);
4299 }
4300
4301 static int selinux_socket_shutdown(struct socket *sock, int how)
4302 {
4303         return sock_has_perm(current, sock->sk, SOCKET__SHUTDOWN);
4304 }
4305
4306 static int selinux_socket_unix_stream_connect(struct sock *sock,
4307                                               struct sock *other,
4308                                               struct sock *newsk)
4309 {
4310         struct sk_security_struct *sksec_sock = sock->sk_security;
4311         struct sk_security_struct *sksec_other = other->sk_security;
4312         struct sk_security_struct *sksec_new = newsk->sk_security;
4313         struct common_audit_data ad;
4314         struct lsm_network_audit net = {0,};
4315         int err;
4316
4317         ad.type = LSM_AUDIT_DATA_NET;
4318         ad.u.net = &net;
4319         ad.u.net->sk = other;
4320
4321         err = avc_has_perm(sksec_sock->sid, sksec_other->sid,
4322                            sksec_other->sclass,
4323                            UNIX_STREAM_SOCKET__CONNECTTO, &ad);
4324         if (err)
4325                 return err;
4326
4327         /* server child socket */
4328         sksec_new->peer_sid = sksec_sock->sid;
4329         err = security_sid_mls_copy(sksec_other->sid, sksec_sock->sid,
4330                                     &sksec_new->sid);
4331         if (err)
4332                 return err;
4333
4334         /* connecting socket */
4335         sksec_sock->peer_sid = sksec_new->sid;
4336
4337         return 0;
4338 }
4339
4340 static int selinux_socket_unix_may_send(struct socket *sock,
4341                                         struct socket *other)
4342 {
4343         struct sk_security_struct *ssec = sock->sk->sk_security;
4344         struct sk_security_struct *osec = other->sk->sk_security;
4345         struct common_audit_data ad;
4346         struct lsm_network_audit net = {0,};
4347
4348         ad.type = LSM_AUDIT_DATA_NET;
4349         ad.u.net = &net;
4350         ad.u.net->sk = other->sk;
4351
4352         return avc_has_perm(ssec->sid, osec->sid, osec->sclass, SOCKET__SENDTO,
4353                             &ad);
4354 }
4355
4356 static int selinux_inet_sys_rcv_skb(struct net *ns, int ifindex,
4357                                     char *addrp, u16 family, u32 peer_sid,
4358                                     struct common_audit_data *ad)
4359 {
4360         int err;
4361         u32 if_sid;
4362         u32 node_sid;
4363
4364         err = sel_netif_sid(ns, ifindex, &if_sid);
4365         if (err)
4366                 return err;
4367         err = avc_has_perm(peer_sid, if_sid,
4368                            SECCLASS_NETIF, NETIF__INGRESS, ad);
4369         if (err)
4370                 return err;
4371
4372         err = sel_netnode_sid(addrp, family, &node_sid);
4373         if (err)
4374                 return err;
4375         return avc_has_perm(peer_sid, node_sid,
4376                             SECCLASS_NODE, NODE__RECVFROM, ad);
4377 }
4378
4379 static int selinux_sock_rcv_skb_compat(struct sock *sk, struct sk_buff *skb,
4380                                        u16 family)
4381 {
4382         int err = 0;
4383         struct sk_security_struct *sksec = sk->sk_security;
4384         u32 sk_sid = sksec->sid;
4385         struct common_audit_data ad;
4386         struct lsm_network_audit net = {0,};
4387         char *addrp;
4388
4389         ad.type = LSM_AUDIT_DATA_NET;
4390         ad.u.net = &net;
4391         ad.u.net->netif = skb->skb_iif;
4392         ad.u.net->family = family;
4393         err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL);
4394         if (err)
4395                 return err;
4396
4397         if (selinux_secmark_enabled()) {
4398                 err = avc_has_perm(sk_sid, skb->secmark, SECCLASS_PACKET,
4399                                    PACKET__RECV, &ad);
4400                 if (err)
4401                         return err;
4402         }
4403
4404         err = selinux_netlbl_sock_rcv_skb(sksec, skb, family, &ad);
4405         if (err)
4406                 return err;
4407         err = selinux_xfrm_sock_rcv_skb(sksec->sid, skb, &ad);
4408
4409         return err;
4410 }
4411
4412 static int selinux_socket_sock_rcv_skb(struct sock *sk, struct sk_buff *skb)
4413 {
4414         int err;
4415         struct sk_security_struct *sksec = sk->sk_security;
4416         u16 family = sk->sk_family;
4417         u32 sk_sid = sksec->sid;
4418         struct common_audit_data ad;
4419         struct lsm_network_audit net = {0,};
4420         char *addrp;
4421         u8 secmark_active;
4422         u8 peerlbl_active;
4423
4424         if (family != PF_INET && family != PF_INET6)
4425                 return 0;
4426
4427         /* Handle mapped IPv4 packets arriving via IPv6 sockets */
4428         if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
4429                 family = PF_INET;
4430
4431         /* If any sort of compatibility mode is enabled then handoff processing
4432          * to the selinux_sock_rcv_skb_compat() function to deal with the
4433          * special handling.  We do this in an attempt to keep this function
4434          * as fast and as clean as possible. */
4435         if (!selinux_policycap_netpeer)
4436                 return selinux_sock_rcv_skb_compat(sk, skb, family);
4437
4438         secmark_active = selinux_secmark_enabled();
4439         peerlbl_active = selinux_peerlbl_enabled();
4440         if (!secmark_active && !peerlbl_active)
4441                 return 0;
4442
4443         ad.type = LSM_AUDIT_DATA_NET;
4444         ad.u.net = &net;
4445         ad.u.net->netif = skb->skb_iif;
4446         ad.u.net->family = family;
4447         err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL);
4448         if (err)
4449                 return err;
4450
4451         if (peerlbl_active) {
4452                 u32 peer_sid;
4453
4454                 err = selinux_skb_peerlbl_sid(skb, family, &peer_sid);
4455                 if (err)
4456                         return err;
4457                 err = selinux_inet_sys_rcv_skb(sock_net(sk), skb->skb_iif,
4458                                                addrp, family, peer_sid, &ad);
4459                 if (err) {
4460                         selinux_netlbl_err(skb, err, 0);
4461                         return err;
4462                 }
4463                 err = avc_has_perm(sk_sid, peer_sid, SECCLASS_PEER,
4464                                    PEER__RECV, &ad);
4465                 if (err) {
4466                         selinux_netlbl_err(skb, err, 0);
4467                         return err;
4468                 }
4469         }
4470
4471         if (secmark_active) {
4472                 err = avc_has_perm(sk_sid, skb->secmark, SECCLASS_PACKET,
4473                                    PACKET__RECV, &ad);
4474                 if (err)
4475                         return err;
4476         }
4477
4478         return err;
4479 }
4480
4481 static int selinux_socket_getpeersec_stream(struct socket *sock, char __user *optval,
4482                                             int __user *optlen, unsigned len)
4483 {
4484         int err = 0;
4485         char *scontext;
4486         u32 scontext_len;
4487         struct sk_security_struct *sksec = sock->sk->sk_security;
4488         u32 peer_sid = SECSID_NULL;
4489
4490         if (sksec->sclass == SECCLASS_UNIX_STREAM_SOCKET ||
4491             sksec->sclass == SECCLASS_TCP_SOCKET)
4492                 peer_sid = sksec->peer_sid;
4493         if (peer_sid == SECSID_NULL)
4494                 return -ENOPROTOOPT;
4495
4496         err = security_sid_to_context(peer_sid, &scontext, &scontext_len);
4497         if (err)
4498                 return err;
4499
4500         if (scontext_len > len) {
4501                 err = -ERANGE;
4502                 goto out_len;
4503         }
4504
4505         if (copy_to_user(optval, scontext, scontext_len))
4506                 err = -EFAULT;
4507
4508 out_len:
4509         if (put_user(scontext_len, optlen))
4510                 err = -EFAULT;
4511         kfree(scontext);
4512         return err;
4513 }
4514
4515 static int selinux_socket_getpeersec_dgram(struct socket *sock, struct sk_buff *skb, u32 *secid)
4516 {
4517         u32 peer_secid = SECSID_NULL;
4518         u16 family;
4519
4520         if (skb && skb->protocol == htons(ETH_P_IP))
4521                 family = PF_INET;
4522         else if (skb && skb->protocol == htons(ETH_P_IPV6))
4523                 family = PF_INET6;
4524         else if (sock)
4525                 family = sock->sk->sk_family;
4526         else
4527                 goto out;
4528
4529         if (sock && family == PF_UNIX)
4530                 selinux_inode_getsecid(SOCK_INODE(sock), &peer_secid);
4531         else if (skb)
4532                 selinux_skb_peerlbl_sid(skb, family, &peer_secid);
4533
4534 out:
4535         *secid = peer_secid;
4536         if (peer_secid == SECSID_NULL)
4537                 return -EINVAL;
4538         return 0;
4539 }
4540
4541 static int selinux_sk_alloc_security(struct sock *sk, int family, gfp_t priority)
4542 {
4543         struct sk_security_struct *sksec;
4544
4545         sksec = kzalloc(sizeof(*sksec), priority);
4546         if (!sksec)
4547                 return -ENOMEM;
4548
4549         sksec->peer_sid = SECINITSID_UNLABELED;
4550         sksec->sid = SECINITSID_UNLABELED;
4551         selinux_netlbl_sk_security_reset(sksec);
4552         sk->sk_security = sksec;
4553
4554         return 0;
4555 }
4556
4557 static void selinux_sk_free_security(struct sock *sk)
4558 {
4559         struct sk_security_struct *sksec = sk->sk_security;
4560
4561         sk->sk_security = NULL;
4562         selinux_netlbl_sk_security_free(sksec);
4563         kfree(sksec);
4564 }
4565
4566 static void selinux_sk_clone_security(const struct sock *sk, struct sock *newsk)
4567 {
4568         struct sk_security_struct *sksec = sk->sk_security;
4569         struct sk_security_struct *newsksec = newsk->sk_security;
4570
4571         newsksec->sid = sksec->sid;
4572         newsksec->peer_sid = sksec->peer_sid;
4573         newsksec->sclass = sksec->sclass;
4574
4575         selinux_netlbl_sk_security_reset(newsksec);
4576 }
4577
4578 static void selinux_sk_getsecid(struct sock *sk, u32 *secid)
4579 {
4580         if (!sk)
4581                 *secid = SECINITSID_ANY_SOCKET;
4582         else {
4583                 struct sk_security_struct *sksec = sk->sk_security;
4584
4585                 *secid = sksec->sid;
4586         }
4587 }
4588
4589 static void selinux_sock_graft(struct sock *sk, struct socket *parent)
4590 {
4591         struct inode_security_struct *isec = SOCK_INODE(parent)->i_security;
4592         struct sk_security_struct *sksec = sk->sk_security;
4593
4594         if (sk->sk_family == PF_INET || sk->sk_family == PF_INET6 ||
4595             sk->sk_family == PF_UNIX)
4596                 isec->sid = sksec->sid;
4597         sksec->sclass = isec->sclass;
4598 }
4599
4600 static int selinux_inet_conn_request(struct sock *sk, struct sk_buff *skb,
4601                                      struct request_sock *req)
4602 {
4603         struct sk_security_struct *sksec = sk->sk_security;
4604         int err;
4605         u16 family = req->rsk_ops->family;
4606         u32 connsid;
4607         u32 peersid;
4608
4609         err = selinux_skb_peerlbl_sid(skb, family, &peersid);
4610         if (err)
4611                 return err;
4612         err = selinux_conn_sid(sksec->sid, peersid, &connsid);
4613         if (err)
4614                 return err;
4615         req->secid = connsid;
4616         req->peer_secid = peersid;
4617
4618         return selinux_netlbl_inet_conn_request(req, family);
4619 }
4620
4621 static void selinux_inet_csk_clone(struct sock *newsk,
4622                                    const struct request_sock *req)
4623 {
4624         struct sk_security_struct *newsksec = newsk->sk_security;
4625
4626         newsksec->sid = req->secid;
4627         newsksec->peer_sid = req->peer_secid;
4628         /* NOTE: Ideally, we should also get the isec->sid for the
4629            new socket in sync, but we don't have the isec available yet.
4630            So we will wait until sock_graft to do it, by which
4631            time it will have been created and available. */
4632
4633         /* We don't need to take any sort of lock here as we are the only
4634          * thread with access to newsksec */
4635         selinux_netlbl_inet_csk_clone(newsk, req->rsk_ops->family);
4636 }
4637
4638 static void selinux_inet_conn_established(struct sock *sk, struct sk_buff *skb)
4639 {
4640         u16 family = sk->sk_family;
4641         struct sk_security_struct *sksec = sk->sk_security;
4642
4643         /* handle mapped IPv4 packets arriving via IPv6 sockets */
4644         if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
4645                 family = PF_INET;
4646
4647         selinux_skb_peerlbl_sid(skb, family, &sksec->peer_sid);
4648 }
4649
4650 static int selinux_secmark_relabel_packet(u32 sid)
4651 {
4652         const struct task_security_struct *__tsec;
4653         u32 tsid;
4654
4655         __tsec = current_security();
4656         tsid = __tsec->sid;
4657
4658         return avc_has_perm(tsid, sid, SECCLASS_PACKET, PACKET__RELABELTO, NULL);
4659 }
4660
4661 static void selinux_secmark_refcount_inc(void)
4662 {
4663         atomic_inc(&selinux_secmark_refcount);
4664 }
4665
4666 static void selinux_secmark_refcount_dec(void)
4667 {
4668         atomic_dec(&selinux_secmark_refcount);
4669 }
4670
4671 static void selinux_req_classify_flow(const struct request_sock *req,
4672                                       struct flowi *fl)
4673 {
4674         fl->flowi_secid = req->secid;
4675 }
4676
4677 static int selinux_tun_dev_alloc_security(void **security)
4678 {
4679         struct tun_security_struct *tunsec;
4680
4681         tunsec = kzalloc(sizeof(*tunsec), GFP_KERNEL);
4682         if (!tunsec)
4683                 return -ENOMEM;
4684         tunsec->sid = current_sid();
4685
4686         *security = tunsec;
4687         return 0;
4688 }
4689
4690 static void selinux_tun_dev_free_security(void *security)
4691 {
4692         kfree(security);
4693 }
4694
4695 static int selinux_tun_dev_create(void)
4696 {
4697         u32 sid = current_sid();
4698
4699         /* we aren't taking into account the "sockcreate" SID since the socket
4700          * that is being created here is not a socket in the traditional sense,
4701          * instead it is a private sock, accessible only to the kernel, and
4702          * representing a wide range of network traffic spanning multiple
4703          * connections unlike traditional sockets - check the TUN driver to
4704          * get a better understanding of why this socket is special */
4705
4706         return avc_has_perm(sid, sid, SECCLASS_TUN_SOCKET, TUN_SOCKET__CREATE,
4707                             NULL);
4708 }
4709
4710 static int selinux_tun_dev_attach_queue(void *security)
4711 {
4712         struct tun_security_struct *tunsec = security;
4713
4714         return avc_has_perm(current_sid(), tunsec->sid, SECCLASS_TUN_SOCKET,
4715                             TUN_SOCKET__ATTACH_QUEUE, NULL);
4716 }
4717
4718 static int selinux_tun_dev_attach(struct sock *sk, void *security)
4719 {
4720         struct tun_security_struct *tunsec = security;
4721         struct sk_security_struct *sksec = sk->sk_security;
4722
4723         /* we don't currently perform any NetLabel based labeling here and it
4724          * isn't clear that we would want to do so anyway; while we could apply
4725          * labeling without the support of the TUN user the resulting labeled
4726          * traffic from the other end of the connection would almost certainly
4727          * cause confusion to the TUN user that had no idea network labeling
4728          * protocols were being used */
4729
4730         sksec->sid = tunsec->sid;
4731         sksec->sclass = SECCLASS_TUN_SOCKET;
4732
4733         return 0;
4734 }
4735
4736 static int selinux_tun_dev_open(void *security)
4737 {
4738         struct tun_security_struct *tunsec = security;
4739         u32 sid = current_sid();
4740         int err;
4741
4742         err = avc_has_perm(sid, tunsec->sid, SECCLASS_TUN_SOCKET,
4743                            TUN_SOCKET__RELABELFROM, NULL);
4744         if (err)
4745                 return err;
4746         err = avc_has_perm(sid, sid, SECCLASS_TUN_SOCKET,
4747                            TUN_SOCKET__RELABELTO, NULL);
4748         if (err)
4749                 return err;
4750         tunsec->sid = sid;
4751
4752         return 0;
4753 }
4754
4755 static int selinux_nlmsg_perm(struct sock *sk, struct sk_buff *skb)
4756 {
4757         int err = 0;
4758         u32 perm;
4759         struct nlmsghdr *nlh;
4760         struct sk_security_struct *sksec = sk->sk_security;
4761
4762         if (skb->len < NLMSG_HDRLEN) {
4763                 err = -EINVAL;
4764                 goto out;
4765         }
4766         nlh = nlmsg_hdr(skb);
4767
4768         err = selinux_nlmsg_lookup(sksec->sclass, nlh->nlmsg_type, &perm);
4769         if (err) {
4770                 if (err == -EINVAL) {
4771                         printk(KERN_WARNING
4772                                "SELinux: unrecognized netlink message:"
4773                                " protocol=%hu nlmsg_type=%hu sclass=%hu\n",
4774                                sk->sk_protocol, nlh->nlmsg_type, sksec->sclass);
4775                         if (!selinux_enforcing || security_get_allow_unknown())
4776                                 err = 0;
4777                 }
4778
4779                 /* Ignore */
4780                 if (err == -ENOENT)
4781                         err = 0;
4782                 goto out;
4783         }
4784
4785         err = sock_has_perm(current, sk, perm);
4786 out:
4787         return err;
4788 }
4789
4790 #ifdef CONFIG_NETFILTER
4791
4792 static unsigned int selinux_ip_forward(struct sk_buff *skb,
4793                                        const struct net_device *indev,
4794                                        u16 family)
4795 {
4796         int err;
4797         char *addrp;
4798         u32 peer_sid;
4799         struct common_audit_data ad;
4800         struct lsm_network_audit net = {0,};
4801         u8 secmark_active;
4802         u8 netlbl_active;
4803         u8 peerlbl_active;
4804
4805         if (!selinux_policycap_netpeer)
4806                 return NF_ACCEPT;
4807
4808         secmark_active = selinux_secmark_enabled();
4809         netlbl_active = netlbl_enabled();
4810         peerlbl_active = selinux_peerlbl_enabled();
4811         if (!secmark_active && !peerlbl_active)
4812                 return NF_ACCEPT;
4813
4814         if (selinux_skb_peerlbl_sid(skb, family, &peer_sid) != 0)
4815                 return NF_DROP;
4816
4817         ad.type = LSM_AUDIT_DATA_NET;
4818         ad.u.net = &net;
4819         ad.u.net->netif = indev->ifindex;
4820         ad.u.net->family = family;
4821         if (selinux_parse_skb(skb, &ad, &addrp, 1, NULL) != 0)
4822                 return NF_DROP;
4823
4824         if (peerlbl_active) {
4825                 err = selinux_inet_sys_rcv_skb(dev_net(indev), indev->ifindex,
4826                                                addrp, family, peer_sid, &ad);
4827                 if (err) {
4828                         selinux_netlbl_err(skb, err, 1);
4829                         return NF_DROP;
4830                 }
4831         }
4832
4833         if (secmark_active)
4834                 if (avc_has_perm(peer_sid, skb->secmark,
4835                                  SECCLASS_PACKET, PACKET__FORWARD_IN, &ad))
4836                         return NF_DROP;
4837
4838         if (netlbl_active)
4839                 /* we do this in the FORWARD path and not the POST_ROUTING
4840                  * path because we want to make sure we apply the necessary
4841                  * labeling before IPsec is applied so we can leverage AH
4842                  * protection */
4843                 if (selinux_netlbl_skbuff_setsid(skb, family, peer_sid) != 0)
4844                         return NF_DROP;
4845
4846         return NF_ACCEPT;
4847 }
4848
4849 static unsigned int selinux_ipv4_forward(const struct nf_hook_ops *ops,
4850                                          struct sk_buff *skb,
4851                                          const struct nf_hook_state *state)
4852 {
4853         return selinux_ip_forward(skb, state->in, PF_INET);
4854 }
4855
4856 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
4857 static unsigned int selinux_ipv6_forward(const struct nf_hook_ops *ops,
4858                                          struct sk_buff *skb,
4859                                          const struct nf_hook_state *state)
4860 {
4861         return selinux_ip_forward(skb, state->in, PF_INET6);
4862 }
4863 #endif  /* IPV6 */
4864
4865 static unsigned int selinux_ip_output(struct sk_buff *skb,
4866                                       u16 family)
4867 {
4868         struct sock *sk;
4869         u32 sid;
4870
4871         if (!netlbl_enabled())
4872                 return NF_ACCEPT;
4873
4874         /* we do this in the LOCAL_OUT path and not the POST_ROUTING path
4875          * because we want to make sure we apply the necessary labeling
4876          * before IPsec is applied so we can leverage AH protection */
4877         sk = skb->sk;
4878         if (sk) {
4879                 struct sk_security_struct *sksec;
4880
4881                 if (sk->sk_state == TCP_LISTEN)
4882                         /* if the socket is the listening state then this
4883                          * packet is a SYN-ACK packet which means it needs to
4884                          * be labeled based on the connection/request_sock and
4885                          * not the parent socket.  unfortunately, we can't
4886                          * lookup the request_sock yet as it isn't queued on
4887                          * the parent socket until after the SYN-ACK is sent.
4888                          * the "solution" is to simply pass the packet as-is
4889                          * as any IP option based labeling should be copied
4890                          * from the initial connection request (in the IP
4891                          * layer).  it is far from ideal, but until we get a
4892                          * security label in the packet itself this is the
4893                          * best we can do. */
4894                         return NF_ACCEPT;
4895
4896                 /* standard practice, label using the parent socket */
4897                 sksec = sk->sk_security;
4898                 sid = sksec->sid;
4899         } else
4900                 sid = SECINITSID_KERNEL;
4901         if (selinux_netlbl_skbuff_setsid(skb, family, sid) != 0)
4902                 return NF_DROP;
4903
4904         return NF_ACCEPT;
4905 }
4906
4907 static unsigned int selinux_ipv4_output(const struct nf_hook_ops *ops,
4908                                         struct sk_buff *skb,
4909                                         const struct nf_hook_state *state)
4910 {
4911         return selinux_ip_output(skb, PF_INET);
4912 }
4913
4914 static unsigned int selinux_ip_postroute_compat(struct sk_buff *skb,
4915                                                 int ifindex,
4916                                                 u16 family)
4917 {
4918         struct sock *sk = skb->sk;
4919         struct sk_security_struct *sksec;
4920         struct common_audit_data ad;
4921         struct lsm_network_audit net = {0,};
4922         char *addrp;
4923         u8 proto;
4924
4925         if (sk == NULL)
4926                 return NF_ACCEPT;
4927         sksec = sk->sk_security;
4928
4929         ad.type = LSM_AUDIT_DATA_NET;
4930         ad.u.net = &net;
4931         ad.u.net->netif = ifindex;
4932         ad.u.net->family = family;
4933         if (selinux_parse_skb(skb, &ad, &addrp, 0, &proto))
4934                 return NF_DROP;
4935
4936         if (selinux_secmark_enabled())
4937                 if (avc_has_perm(sksec->sid, skb->secmark,
4938                                  SECCLASS_PACKET, PACKET__SEND, &ad))
4939                         return NF_DROP_ERR(-ECONNREFUSED);
4940
4941         if (selinux_xfrm_postroute_last(sksec->sid, skb, &ad, proto))
4942                 return NF_DROP_ERR(-ECONNREFUSED);
4943
4944         return NF_ACCEPT;
4945 }
4946
4947 static unsigned int selinux_ip_postroute(struct sk_buff *skb,
4948                                          const struct net_device *outdev,
4949                                          u16 family)
4950 {
4951         u32 secmark_perm;
4952         u32 peer_sid;
4953         int ifindex = outdev->ifindex;
4954         struct sock *sk;
4955         struct common_audit_data ad;
4956         struct lsm_network_audit net = {0,};
4957         char *addrp;
4958         u8 secmark_active;
4959         u8 peerlbl_active;
4960
4961         /* If any sort of compatibility mode is enabled then handoff processing
4962          * to the selinux_ip_postroute_compat() function to deal with the
4963          * special handling.  We do this in an attempt to keep this function
4964          * as fast and as clean as possible. */
4965         if (!selinux_policycap_netpeer)
4966                 return selinux_ip_postroute_compat(skb, ifindex, family);
4967
4968         secmark_active = selinux_secmark_enabled();
4969         peerlbl_active = selinux_peerlbl_enabled();
4970         if (!secmark_active && !peerlbl_active)
4971                 return NF_ACCEPT;
4972
4973         sk = skb->sk;
4974
4975 #ifdef CONFIG_XFRM
4976         /* If skb->dst->xfrm is non-NULL then the packet is undergoing an IPsec
4977          * packet transformation so allow the packet to pass without any checks
4978          * since we'll have another chance to perform access control checks
4979          * when the packet is on it's final way out.
4980          * NOTE: there appear to be some IPv6 multicast cases where skb->dst
4981          *       is NULL, in this case go ahead and apply access control.
4982          * NOTE: if this is a local socket (skb->sk != NULL) that is in the
4983          *       TCP listening state we cannot wait until the XFRM processing
4984          *       is done as we will miss out on the SA label if we do;
4985          *       unfortunately, this means more work, but it is only once per
4986          *       connection. */
4987         if (skb_dst(skb) != NULL && skb_dst(skb)->xfrm != NULL &&
4988             !(sk != NULL && sk->sk_state == TCP_LISTEN))
4989                 return NF_ACCEPT;
4990 #endif
4991
4992         if (sk == NULL) {
4993                 /* Without an associated socket the packet is either coming
4994                  * from the kernel or it is being forwarded; check the packet
4995                  * to determine which and if the packet is being forwarded
4996                  * query the packet directly to determine the security label. */
4997                 if (skb->skb_iif) {
4998                         secmark_perm = PACKET__FORWARD_OUT;
4999                         if (selinux_skb_peerlbl_sid(skb, family, &peer_sid))
5000                                 return NF_DROP;
5001                 } else {
5002                         secmark_perm = PACKET__SEND;
5003                         peer_sid = SECINITSID_KERNEL;
5004                 }
5005         } else if (sk->sk_state == TCP_LISTEN) {
5006                 /* Locally generated packet but the associated socket is in the
5007                  * listening state which means this is a SYN-ACK packet.  In
5008                  * this particular case the correct security label is assigned
5009                  * to the connection/request_sock but unfortunately we can't
5010                  * query the request_sock as it isn't queued on the parent
5011                  * socket until after the SYN-ACK packet is sent; the only
5012                  * viable choice is to regenerate the label like we do in
5013                  * selinux_inet_conn_request().  See also selinux_ip_output()
5014                  * for similar problems. */
5015                 u32 skb_sid;
5016                 struct sk_security_struct *sksec = sk->sk_security;
5017                 if (selinux_skb_peerlbl_sid(skb, family, &skb_sid))
5018                         return NF_DROP;
5019                 /* At this point, if the returned skb peerlbl is SECSID_NULL
5020                  * and the packet has been through at least one XFRM
5021                  * transformation then we must be dealing with the "final"
5022                  * form of labeled IPsec packet; since we've already applied
5023                  * all of our access controls on this packet we can safely
5024                  * pass the packet. */
5025                 if (skb_sid == SECSID_NULL) {
5026                         switch (family) {
5027                         case PF_INET:
5028                                 if (IPCB(skb)->flags & IPSKB_XFRM_TRANSFORMED)
5029                                         return NF_ACCEPT;
5030                                 break;
5031                         case PF_INET6:
5032                                 if (IP6CB(skb)->flags & IP6SKB_XFRM_TRANSFORMED)
5033                                         return NF_ACCEPT;
5034                                 break;
5035                         default:
5036                                 return NF_DROP_ERR(-ECONNREFUSED);
5037                         }
5038                 }
5039                 if (selinux_conn_sid(sksec->sid, skb_sid, &peer_sid))
5040                         return NF_DROP;
5041                 secmark_perm = PACKET__SEND;
5042         } else {
5043                 /* Locally generated packet, fetch the security label from the
5044                  * associated socket. */
5045                 struct sk_security_struct *sksec = sk->sk_security;
5046                 peer_sid = sksec->sid;
5047                 secmark_perm = PACKET__SEND;
5048         }
5049
5050         ad.type = LSM_AUDIT_DATA_NET;
5051         ad.u.net = &net;
5052         ad.u.net->netif = ifindex;
5053         ad.u.net->family = family;
5054         if (selinux_parse_skb(skb, &ad, &addrp, 0, NULL))
5055                 return NF_DROP;
5056
5057         if (secmark_active)
5058                 if (avc_has_perm(peer_sid, skb->secmark,
5059                                  SECCLASS_PACKET, secmark_perm, &ad))
5060                         return NF_DROP_ERR(-ECONNREFUSED);
5061
5062         if (peerlbl_active) {
5063                 u32 if_sid;
5064                 u32 node_sid;
5065
5066                 if (sel_netif_sid(dev_net(outdev), ifindex, &if_sid))
5067                         return NF_DROP;
5068                 if (avc_has_perm(peer_sid, if_sid,
5069                                  SECCLASS_NETIF, NETIF__EGRESS, &ad))
5070                         return NF_DROP_ERR(-ECONNREFUSED);
5071
5072                 if (sel_netnode_sid(addrp, family, &node_sid))
5073                         return NF_DROP;
5074                 if (avc_has_perm(peer_sid, node_sid,
5075                                  SECCLASS_NODE, NODE__SENDTO, &ad))
5076                         return NF_DROP_ERR(-ECONNREFUSED);
5077         }
5078
5079         return NF_ACCEPT;
5080 }
5081
5082 static unsigned int selinux_ipv4_postroute(const struct nf_hook_ops *ops,
5083                                            struct sk_buff *skb,
5084                                            const struct nf_hook_state *state)
5085 {
5086         return selinux_ip_postroute(skb, state->out, PF_INET);
5087 }
5088
5089 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
5090 static unsigned int selinux_ipv6_postroute(const struct nf_hook_ops *ops,
5091                                            struct sk_buff *skb,
5092                                            const struct nf_hook_state *state)
5093 {
5094         return selinux_ip_postroute(skb, state->out, PF_INET6);
5095 }
5096 #endif  /* IPV6 */
5097
5098 #endif  /* CONFIG_NETFILTER */
5099
5100 static int selinux_netlink_send(struct sock *sk, struct sk_buff *skb)
5101 {
5102         int err;
5103
5104         err = cap_netlink_send(sk, skb);
5105         if (err)
5106                 return err;
5107
5108         return selinux_nlmsg_perm(sk, skb);
5109 }
5110
5111 static int ipc_alloc_security(struct task_struct *task,
5112                               struct kern_ipc_perm *perm,
5113                               u16 sclass)
5114 {
5115         struct ipc_security_struct *isec;
5116         u32 sid;
5117
5118         isec = kzalloc(sizeof(struct ipc_security_struct), GFP_KERNEL);
5119         if (!isec)
5120                 return -ENOMEM;
5121
5122         sid = task_sid(task);
5123         isec->sclass = sclass;
5124         isec->sid = sid;
5125         perm->security = isec;
5126
5127         return 0;
5128 }
5129
5130 static void ipc_free_security(struct kern_ipc_perm *perm)
5131 {
5132         struct ipc_security_struct *isec = perm->security;
5133         perm->security = NULL;
5134         kfree(isec);
5135 }
5136
5137 static int msg_msg_alloc_security(struct msg_msg *msg)
5138 {
5139         struct msg_security_struct *msec;
5140
5141         msec = kzalloc(sizeof(struct msg_security_struct), GFP_KERNEL);
5142         if (!msec)
5143                 return -ENOMEM;
5144
5145         msec->sid = SECINITSID_UNLABELED;
5146         msg->security = msec;
5147
5148         return 0;
5149 }
5150
5151 static void msg_msg_free_security(struct msg_msg *msg)
5152 {
5153         struct msg_security_struct *msec = msg->security;
5154
5155         msg->security = NULL;
5156         kfree(msec);
5157 }
5158
5159 static int ipc_has_perm(struct kern_ipc_perm *ipc_perms,
5160                         u32 perms)
5161 {
5162         struct ipc_security_struct *isec;
5163         struct common_audit_data ad;
5164         u32 sid = current_sid();
5165
5166         isec = ipc_perms->security;
5167
5168         ad.type = LSM_AUDIT_DATA_IPC;
5169         ad.u.ipc_id = ipc_perms->key;
5170
5171         return avc_has_perm(sid, isec->sid, isec->sclass, perms, &ad);
5172 }
5173
5174 static int selinux_msg_msg_alloc_security(struct msg_msg *msg)
5175 {
5176         return msg_msg_alloc_security(msg);
5177 }
5178
5179 static void selinux_msg_msg_free_security(struct msg_msg *msg)
5180 {
5181         msg_msg_free_security(msg);
5182 }
5183
5184 /* message queue security operations */
5185 static int selinux_msg_queue_alloc_security(struct msg_queue *msq)
5186 {
5187         struct ipc_security_struct *isec;
5188         struct common_audit_data ad;
5189         u32 sid = current_sid();
5190         int rc;
5191
5192         rc = ipc_alloc_security(current, &msq->q_perm, SECCLASS_MSGQ);
5193         if (rc)
5194                 return rc;
5195
5196         isec = msq->q_perm.security;
5197
5198         ad.type = LSM_AUDIT_DATA_IPC;
5199         ad.u.ipc_id = msq->q_perm.key;
5200
5201         rc = avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
5202                           MSGQ__CREATE, &ad);
5203         if (rc) {
5204                 ipc_free_security(&msq->q_perm);
5205                 return rc;
5206         }
5207         return 0;
5208 }
5209
5210 static void selinux_msg_queue_free_security(struct msg_queue *msq)
5211 {
5212         ipc_free_security(&msq->q_perm);
5213 }
5214
5215 static int selinux_msg_queue_associate(struct msg_queue *msq, int msqflg)
5216 {
5217         struct ipc_security_struct *isec;
5218         struct common_audit_data ad;
5219         u32 sid = current_sid();
5220
5221         isec = msq->q_perm.security;
5222
5223         ad.type = LSM_AUDIT_DATA_IPC;
5224         ad.u.ipc_id = msq->q_perm.key;
5225
5226         return avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
5227                             MSGQ__ASSOCIATE, &ad);
5228 }
5229
5230 static int selinux_msg_queue_msgctl(struct msg_queue *msq, int cmd)
5231 {
5232         int err;
5233         int perms;
5234
5235         switch (cmd) {
5236         case IPC_INFO:
5237         case MSG_INFO:
5238                 /* No specific object, just general system-wide information. */
5239                 return task_has_system(current, SYSTEM__IPC_INFO);
5240         case IPC_STAT:
5241         case MSG_STAT:
5242                 perms = MSGQ__GETATTR | MSGQ__ASSOCIATE;
5243                 break;
5244         case IPC_SET:
5245                 perms = MSGQ__SETATTR;
5246                 break;
5247         case IPC_RMID:
5248                 perms = MSGQ__DESTROY;
5249                 break;
5250         default:
5251                 return 0;
5252         }
5253
5254         err = ipc_has_perm(&msq->q_perm, perms);
5255         return err;
5256 }
5257
5258 static int selinux_msg_queue_msgsnd(struct msg_queue *msq, struct msg_msg *msg, int msqflg)
5259 {
5260         struct ipc_security_struct *isec;
5261         struct msg_security_struct *msec;
5262         struct common_audit_data ad;
5263         u32 sid = current_sid();
5264         int rc;
5265
5266         isec = msq->q_perm.security;
5267         msec = msg->security;
5268
5269         /*
5270          * First time through, need to assign label to the message
5271          */
5272         if (msec->sid == SECINITSID_UNLABELED) {
5273                 /*
5274                  * Compute new sid based on current process and
5275                  * message queue this message will be stored in
5276                  */
5277                 rc = security_transition_sid(sid, isec->sid, SECCLASS_MSG,
5278                                              NULL, &msec->sid);
5279                 if (rc)
5280                         return rc;
5281         }
5282
5283         ad.type = LSM_AUDIT_DATA_IPC;
5284         ad.u.ipc_id = msq->q_perm.key;
5285
5286         /* Can this process write to the queue? */
5287         rc = avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
5288                           MSGQ__WRITE, &ad);
5289         if (!rc)
5290                 /* Can this process send the message */
5291                 rc = avc_has_perm(sid, msec->sid, SECCLASS_MSG,
5292                                   MSG__SEND, &ad);
5293         if (!rc)
5294                 /* Can the message be put in the queue? */
5295                 rc = avc_has_perm(msec->sid, isec->sid, SECCLASS_MSGQ,
5296                                   MSGQ__ENQUEUE, &ad);
5297
5298         return rc;
5299 }
5300
5301 static int selinux_msg_queue_msgrcv(struct msg_queue *msq, struct msg_msg *msg,
5302                                     struct task_struct *target,
5303                                     long type, int mode)
5304 {
5305         struct ipc_security_struct *isec;
5306         struct msg_security_struct *msec;
5307         struct common_audit_data ad;
5308         u32 sid = task_sid(target);
5309         int rc;
5310
5311         isec = msq->q_perm.security;
5312         msec = msg->security;
5313
5314         ad.type = LSM_AUDIT_DATA_IPC;
5315         ad.u.ipc_id = msq->q_perm.key;
5316
5317         rc = avc_has_perm(sid, isec->sid,
5318                           SECCLASS_MSGQ, MSGQ__READ, &ad);
5319         if (!rc)
5320                 rc = avc_has_perm(sid, msec->sid,
5321                                   SECCLASS_MSG, MSG__RECEIVE, &ad);
5322         return rc;
5323 }
5324
5325 /* Shared Memory security operations */
5326 static int selinux_shm_alloc_security(struct shmid_kernel *shp)
5327 {
5328         struct ipc_security_struct *isec;
5329         struct common_audit_data ad;
5330         u32 sid = current_sid();
5331         int rc;
5332
5333         rc = ipc_alloc_security(current, &shp->shm_perm, SECCLASS_SHM);
5334         if (rc)
5335                 return rc;
5336
5337         isec = shp->shm_perm.security;
5338
5339         ad.type = LSM_AUDIT_DATA_IPC;
5340         ad.u.ipc_id = shp->shm_perm.key;
5341
5342         rc = avc_has_perm(sid, isec->sid, SECCLASS_SHM,
5343                           SHM__CREATE, &ad);
5344         if (rc) {
5345                 ipc_free_security(&shp->shm_perm);
5346                 return rc;
5347         }
5348         return 0;
5349 }
5350
5351 static void selinux_shm_free_security(struct shmid_kernel *shp)
5352 {
5353         ipc_free_security(&shp->shm_perm);
5354 }
5355
5356 static int selinux_shm_associate(struct shmid_kernel *shp, int shmflg)
5357 {
5358         struct ipc_security_struct *isec;
5359         struct common_audit_data ad;
5360         u32 sid = current_sid();
5361
5362         isec = shp->shm_perm.security;
5363
5364         ad.type = LSM_AUDIT_DATA_IPC;
5365         ad.u.ipc_id = shp->shm_perm.key;
5366
5367         return avc_has_perm(sid, isec->sid, SECCLASS_SHM,
5368                             SHM__ASSOCIATE, &ad);
5369 }
5370
5371 /* Note, at this point, shp is locked down */
5372 static int selinux_shm_shmctl(struct shmid_kernel *shp, int cmd)
5373 {
5374         int perms;
5375         int err;
5376
5377         switch (cmd) {
5378         case IPC_INFO:
5379         case SHM_INFO:
5380                 /* No specific object, just general system-wide information. */
5381                 return task_has_system(current, SYSTEM__IPC_INFO);
5382         case IPC_STAT:
5383         case SHM_STAT:
5384                 perms = SHM__GETATTR | SHM__ASSOCIATE;
5385                 break;
5386         case IPC_SET:
5387                 perms = SHM__SETATTR;
5388                 break;
5389         case SHM_LOCK:
5390         case SHM_UNLOCK:
5391                 perms = SHM__LOCK;
5392                 break;
5393         case IPC_RMID:
5394                 perms = SHM__DESTROY;
5395                 break;
5396         default:
5397                 return 0;
5398         }
5399
5400         err = ipc_has_perm(&shp->shm_perm, perms);
5401         return err;
5402 }
5403
5404 static int selinux_shm_shmat(struct shmid_kernel *shp,
5405                              char __user *shmaddr, int shmflg)
5406 {
5407         u32 perms;
5408
5409         if (shmflg & SHM_RDONLY)
5410                 perms = SHM__READ;
5411         else
5412                 perms = SHM__READ | SHM__WRITE;
5413
5414         return ipc_has_perm(&shp->shm_perm, perms);
5415 }
5416
5417 /* Semaphore security operations */
5418 static int selinux_sem_alloc_security(struct sem_array *sma)
5419 {
5420         struct ipc_security_struct *isec;
5421         struct common_audit_data ad;
5422         u32 sid = current_sid();
5423         int rc;
5424
5425         rc = ipc_alloc_security(current, &sma->sem_perm, SECCLASS_SEM);
5426         if (rc)
5427                 return rc;
5428
5429         isec = sma->sem_perm.security;
5430
5431         ad.type = LSM_AUDIT_DATA_IPC;
5432         ad.u.ipc_id = sma->sem_perm.key;
5433
5434         rc = avc_has_perm(sid, isec->sid, SECCLASS_SEM,
5435                           SEM__CREATE, &ad);
5436         if (rc) {
5437                 ipc_free_security(&sma->sem_perm);
5438                 return rc;
5439         }
5440         return 0;
5441 }
5442
5443 static void selinux_sem_free_security(struct sem_array *sma)
5444 {
5445         ipc_free_security(&sma->sem_perm);
5446 }
5447
5448 static int selinux_sem_associate(struct sem_array *sma, int semflg)
5449 {
5450         struct ipc_security_struct *isec;
5451         struct common_audit_data ad;
5452         u32 sid = current_sid();
5453
5454         isec = sma->sem_perm.security;
5455
5456         ad.type = LSM_AUDIT_DATA_IPC;
5457         ad.u.ipc_id = sma->sem_perm.key;
5458
5459         return avc_has_perm(sid, isec->sid, SECCLASS_SEM,
5460                             SEM__ASSOCIATE, &ad);
5461 }
5462
5463 /* Note, at this point, sma is locked down */
5464 static int selinux_sem_semctl(struct sem_array *sma, int cmd)
5465 {
5466         int err;
5467         u32 perms;
5468
5469         switch (cmd) {
5470         case IPC_INFO:
5471         case SEM_INFO:
5472                 /* No specific object, just general system-wide information. */
5473                 return task_has_system(current, SYSTEM__IPC_INFO);
5474         case GETPID:
5475         case GETNCNT:
5476         case GETZCNT:
5477                 perms = SEM__GETATTR;
5478                 break;
5479         case GETVAL:
5480         case GETALL:
5481                 perms = SEM__READ;
5482                 break;
5483         case SETVAL:
5484         case SETALL:
5485                 perms = SEM__WRITE;
5486                 break;
5487         case IPC_RMID:
5488                 perms = SEM__DESTROY;
5489                 break;
5490         case IPC_SET:
5491                 perms = SEM__SETATTR;
5492                 break;
5493         case IPC_STAT:
5494         case SEM_STAT:
5495                 perms = SEM__GETATTR | SEM__ASSOCIATE;
5496                 break;
5497         default:
5498                 return 0;
5499         }
5500
5501         err = ipc_has_perm(&sma->sem_perm, perms);
5502         return err;
5503 }
5504
5505 static int selinux_sem_semop(struct sem_array *sma,
5506                              struct sembuf *sops, unsigned nsops, int alter)
5507 {
5508         u32 perms;
5509
5510         if (alter)
5511                 perms = SEM__READ | SEM__WRITE;
5512         else
5513                 perms = SEM__READ;
5514
5515         return ipc_has_perm(&sma->sem_perm, perms);
5516 }
5517
5518 static int selinux_ipc_permission(struct kern_ipc_perm *ipcp, short flag)
5519 {
5520         u32 av = 0;
5521
5522         av = 0;
5523         if (flag & S_IRUGO)
5524                 av |= IPC__UNIX_READ;
5525         if (flag & S_IWUGO)
5526                 av |= IPC__UNIX_WRITE;
5527
5528         if (av == 0)
5529                 return 0;
5530
5531         return ipc_has_perm(ipcp, av);
5532 }
5533
5534 static void selinux_ipc_getsecid(struct kern_ipc_perm *ipcp, u32 *secid)
5535 {
5536         struct ipc_security_struct *isec = ipcp->security;
5537         *secid = isec->sid;
5538 }
5539
5540 static void selinux_d_instantiate(struct dentry *dentry, struct inode *inode)
5541 {
5542         if (inode)
5543                 inode_doinit_with_dentry(inode, dentry);
5544 }
5545
5546 static int selinux_getprocattr(struct task_struct *p,
5547                                char *name, char **value)
5548 {
5549         const struct task_security_struct *__tsec;
5550         u32 sid;
5551         int error;
5552         unsigned len;
5553
5554         if (current != p) {
5555                 error = current_has_perm(p, PROCESS__GETATTR);
5556                 if (error)
5557                         return error;
5558         }
5559
5560         rcu_read_lock();
5561         __tsec = __task_cred(p)->security;
5562
5563         if (!strcmp(name, "current"))
5564                 sid = __tsec->sid;
5565         else if (!strcmp(name, "prev"))
5566                 sid = __tsec->osid;
5567         else if (!strcmp(name, "exec"))
5568                 sid = __tsec->exec_sid;
5569         else if (!strcmp(name, "fscreate"))
5570                 sid = __tsec->create_sid;
5571         else if (!strcmp(name, "keycreate"))
5572                 sid = __tsec->keycreate_sid;
5573         else if (!strcmp(name, "sockcreate"))
5574                 sid = __tsec->sockcreate_sid;
5575         else
5576                 goto invalid;
5577         rcu_read_unlock();
5578
5579         if (!sid)
5580                 return 0;
5581
5582         error = security_sid_to_context(sid, value, &len);
5583         if (error)
5584                 return error;
5585         return len;
5586
5587 invalid:
5588         rcu_read_unlock();
5589         return -EINVAL;
5590 }
5591
5592 static int selinux_setprocattr(struct task_struct *p,
5593                                char *name, void *value, size_t size)
5594 {
5595         struct task_security_struct *tsec;
5596         struct task_struct *tracer;
5597         struct cred *new;
5598         u32 sid = 0, ptsid;
5599         int error;
5600         char *str = value;
5601
5602         if (current != p) {
5603                 /* SELinux only allows a process to change its own
5604                    security attributes. */
5605                 return -EACCES;
5606         }
5607
5608         /*
5609          * Basic control over ability to set these attributes at all.
5610          * current == p, but we'll pass them separately in case the
5611          * above restriction is ever removed.
5612          */
5613         if (!strcmp(name, "exec"))
5614                 error = current_has_perm(p, PROCESS__SETEXEC);
5615         else if (!strcmp(name, "fscreate"))
5616                 error = current_has_perm(p, PROCESS__SETFSCREATE);
5617         else if (!strcmp(name, "keycreate"))
5618                 error = current_has_perm(p, PROCESS__SETKEYCREATE);
5619         else if (!strcmp(name, "sockcreate"))
5620                 error = current_has_perm(p, PROCESS__SETSOCKCREATE);
5621         else if (!strcmp(name, "current"))
5622                 error = current_has_perm(p, PROCESS__SETCURRENT);
5623         else
5624                 error = -EINVAL;
5625         if (error)
5626                 return error;
5627
5628         /* Obtain a SID for the context, if one was specified. */
5629         if (size && str[1] && str[1] != '\n') {
5630                 if (str[size-1] == '\n') {
5631                         str[size-1] = 0;
5632                         size--;
5633                 }
5634                 error = security_context_to_sid(value, size, &sid, GFP_KERNEL);
5635                 if (error == -EINVAL && !strcmp(name, "fscreate")) {
5636                         if (!capable(CAP_MAC_ADMIN)) {
5637                                 struct audit_buffer *ab;
5638                                 size_t audit_size;
5639
5640                                 /* We strip a nul only if it is at the end, otherwise the
5641                                  * context contains a nul and we should audit that */
5642                                 if (str[size - 1] == '\0')
5643                                         audit_size = size - 1;
5644                                 else
5645                                         audit_size = size;
5646                                 ab = audit_log_start(current->audit_context, GFP_ATOMIC, AUDIT_SELINUX_ERR);
5647                                 audit_log_format(ab, "op=fscreate invalid_context=");
5648                                 audit_log_n_untrustedstring(ab, value, audit_size);
5649                                 audit_log_end(ab);
5650
5651                                 return error;
5652                         }
5653                         error = security_context_to_sid_force(value, size,
5654                                                               &sid);
5655                 }
5656                 if (error)
5657                         return error;
5658         }
5659
5660         new = prepare_creds();
5661         if (!new)
5662                 return -ENOMEM;
5663
5664         /* Permission checking based on the specified context is
5665            performed during the actual operation (execve,
5666            open/mkdir/...), when we know the full context of the
5667            operation.  See selinux_bprm_set_creds for the execve
5668            checks and may_create for the file creation checks. The
5669            operation will then fail if the context is not permitted. */
5670         tsec = new->security;
5671         if (!strcmp(name, "exec")) {
5672                 tsec->exec_sid = sid;
5673         } else if (!strcmp(name, "fscreate")) {
5674                 tsec->create_sid = sid;
5675         } else if (!strcmp(name, "keycreate")) {
5676                 error = may_create_key(sid, p);
5677                 if (error)
5678                         goto abort_change;
5679                 tsec->keycreate_sid = sid;
5680         } else if (!strcmp(name, "sockcreate")) {
5681                 tsec->sockcreate_sid = sid;
5682         } else if (!strcmp(name, "current")) {
5683                 error = -EINVAL;
5684                 if (sid == 0)
5685                         goto abort_change;
5686
5687                 /* Only allow single threaded processes to change context */
5688                 error = -EPERM;
5689                 if (!current_is_single_threaded()) {
5690                         error = security_bounded_transition(tsec->sid, sid);
5691                         if (error)
5692                                 goto abort_change;
5693                 }
5694
5695                 /* Check permissions for the transition. */
5696                 error = avc_has_perm(tsec->sid, sid, SECCLASS_PROCESS,
5697                                      PROCESS__DYNTRANSITION, NULL);
5698                 if (error)
5699                         goto abort_change;
5700
5701                 /* Check for ptracing, and update the task SID if ok.
5702                    Otherwise, leave SID unchanged and fail. */
5703                 ptsid = 0;
5704                 rcu_read_lock();
5705                 tracer = ptrace_parent(p);
5706                 if (tracer)
5707                         ptsid = task_sid(tracer);
5708                 rcu_read_unlock();
5709
5710                 if (tracer) {
5711                         error = avc_has_perm(ptsid, sid, SECCLASS_PROCESS,
5712                                              PROCESS__PTRACE, NULL);
5713                         if (error)
5714                                 goto abort_change;
5715                 }
5716
5717                 tsec->sid = sid;
5718         } else {
5719                 error = -EINVAL;
5720                 goto abort_change;
5721         }
5722
5723         commit_creds(new);
5724         return size;
5725
5726 abort_change:
5727         abort_creds(new);
5728         return error;
5729 }
5730
5731 static int selinux_ismaclabel(const char *name)
5732 {
5733         return (strcmp(name, XATTR_SELINUX_SUFFIX) == 0);
5734 }
5735
5736 static int selinux_secid_to_secctx(u32 secid, char **secdata, u32 *seclen)
5737 {
5738         return security_sid_to_context(secid, secdata, seclen);
5739 }
5740
5741 static int selinux_secctx_to_secid(const char *secdata, u32 seclen, u32 *secid)
5742 {
5743         return security_context_to_sid(secdata, seclen, secid, GFP_KERNEL);
5744 }
5745
5746 static void selinux_release_secctx(char *secdata, u32 seclen)
5747 {
5748         kfree(secdata);
5749 }
5750
5751 /*
5752  *      called with inode->i_mutex locked
5753  */
5754 static int selinux_inode_notifysecctx(struct inode *inode, void *ctx, u32 ctxlen)
5755 {
5756         return selinux_inode_setsecurity(inode, XATTR_SELINUX_SUFFIX, ctx, ctxlen, 0);
5757 }
5758
5759 /*
5760  *      called with inode->i_mutex locked
5761  */
5762 static int selinux_inode_setsecctx(struct dentry *dentry, void *ctx, u32 ctxlen)
5763 {
5764         return __vfs_setxattr_noperm(dentry, XATTR_NAME_SELINUX, ctx, ctxlen, 0);
5765 }
5766
5767 static int selinux_inode_getsecctx(struct inode *inode, void **ctx, u32 *ctxlen)
5768 {
5769         int len = 0;
5770         len = selinux_inode_getsecurity(inode, XATTR_SELINUX_SUFFIX,
5771                                                 ctx, true);
5772         if (len < 0)
5773                 return len;
5774         *ctxlen = len;
5775         return 0;
5776 }
5777 #ifdef CONFIG_KEYS
5778
5779 static int selinux_key_alloc(struct key *k, const struct cred *cred,
5780                              unsigned long flags)
5781 {
5782         const struct task_security_struct *tsec;
5783         struct key_security_struct *ksec;
5784
5785         ksec = kzalloc(sizeof(struct key_security_struct), GFP_KERNEL);
5786         if (!ksec)
5787                 return -ENOMEM;
5788
5789         tsec = cred->security;
5790         if (tsec->keycreate_sid)
5791                 ksec->sid = tsec->keycreate_sid;
5792         else
5793                 ksec->sid = tsec->sid;
5794
5795         k->security = ksec;
5796         return 0;
5797 }
5798
5799 static void selinux_key_free(struct key *k)
5800 {
5801         struct key_security_struct *ksec = k->security;
5802
5803         k->security = NULL;
5804         kfree(ksec);
5805 }
5806
5807 static int selinux_key_permission(key_ref_t key_ref,
5808                                   const struct cred *cred,
5809                                   unsigned perm)
5810 {
5811         struct key *key;
5812         struct key_security_struct *ksec;
5813         u32 sid;
5814
5815         /* if no specific permissions are requested, we skip the
5816            permission check. No serious, additional covert channels
5817            appear to be created. */
5818         if (perm == 0)
5819                 return 0;
5820
5821         sid = cred_sid(cred);
5822
5823         key = key_ref_to_ptr(key_ref);
5824         ksec = key->security;
5825
5826         return avc_has_perm(sid, ksec->sid, SECCLASS_KEY, perm, NULL);
5827 }
5828
5829 static int selinux_key_getsecurity(struct key *key, char **_buffer)
5830 {
5831         struct key_security_struct *ksec = key->security;
5832         char *context = NULL;
5833         unsigned len;
5834         int rc;
5835
5836         rc = security_sid_to_context(ksec->sid, &context, &len);
5837         if (!rc)
5838                 rc = len;
5839         *_buffer = context;
5840         return rc;
5841 }
5842
5843 #endif
5844
5845 static struct security_operations selinux_ops = {
5846         .name =                         "selinux",
5847
5848         .binder_set_context_mgr =       selinux_binder_set_context_mgr,
5849         .binder_transaction =           selinux_binder_transaction,
5850         .binder_transfer_binder =       selinux_binder_transfer_binder,
5851         .binder_transfer_file =         selinux_binder_transfer_file,
5852
5853         .ptrace_access_check =          selinux_ptrace_access_check,
5854         .ptrace_traceme =               selinux_ptrace_traceme,
5855         .capget =                       selinux_capget,
5856         .capset =                       selinux_capset,
5857         .capable =                      selinux_capable,
5858         .quotactl =                     selinux_quotactl,
5859         .quota_on =                     selinux_quota_on,
5860         .syslog =                       selinux_syslog,
5861         .vm_enough_memory =             selinux_vm_enough_memory,
5862
5863         .netlink_send =                 selinux_netlink_send,
5864
5865         .bprm_set_creds =               selinux_bprm_set_creds,
5866         .bprm_committing_creds =        selinux_bprm_committing_creds,
5867         .bprm_committed_creds =         selinux_bprm_committed_creds,
5868         .bprm_secureexec =              selinux_bprm_secureexec,
5869
5870         .sb_alloc_security =            selinux_sb_alloc_security,
5871         .sb_free_security =             selinux_sb_free_security,
5872         .sb_copy_data =                 selinux_sb_copy_data,
5873         .sb_remount =                   selinux_sb_remount,
5874         .sb_kern_mount =                selinux_sb_kern_mount,
5875         .sb_show_options =              selinux_sb_show_options,
5876         .sb_statfs =                    selinux_sb_statfs,
5877         .sb_mount =                     selinux_mount,
5878         .sb_umount =                    selinux_umount,
5879         .sb_set_mnt_opts =              selinux_set_mnt_opts,
5880         .sb_clone_mnt_opts =            selinux_sb_clone_mnt_opts,
5881         .sb_parse_opts_str =            selinux_parse_opts_str,
5882
5883         .dentry_init_security =         selinux_dentry_init_security,
5884
5885         .inode_alloc_security =         selinux_inode_alloc_security,
5886         .inode_free_security =          selinux_inode_free_security,
5887         .inode_init_security =          selinux_inode_init_security,
5888         .inode_create =                 selinux_inode_create,
5889         .inode_link =                   selinux_inode_link,
5890         .inode_unlink =                 selinux_inode_unlink,
5891         .inode_symlink =                selinux_inode_symlink,
5892         .inode_mkdir =                  selinux_inode_mkdir,
5893         .inode_rmdir =                  selinux_inode_rmdir,
5894         .inode_mknod =                  selinux_inode_mknod,
5895         .inode_rename =                 selinux_inode_rename,
5896         .inode_readlink =               selinux_inode_readlink,
5897         .inode_follow_link =            selinux_inode_follow_link,
5898         .inode_permission =             selinux_inode_permission,
5899         .inode_setattr =                selinux_inode_setattr,
5900         .inode_getattr =                selinux_inode_getattr,
5901         .inode_setxattr =               selinux_inode_setxattr,
5902         .inode_post_setxattr =          selinux_inode_post_setxattr,
5903         .inode_getxattr =               selinux_inode_getxattr,
5904         .inode_listxattr =              selinux_inode_listxattr,
5905         .inode_removexattr =            selinux_inode_removexattr,
5906         .inode_getsecurity =            selinux_inode_getsecurity,
5907         .inode_setsecurity =            selinux_inode_setsecurity,
5908         .inode_listsecurity =           selinux_inode_listsecurity,
5909         .inode_getsecid =               selinux_inode_getsecid,
5910
5911         .file_permission =              selinux_file_permission,
5912         .file_alloc_security =          selinux_file_alloc_security,
5913         .file_free_security =           selinux_file_free_security,
5914         .file_ioctl =                   selinux_file_ioctl,
5915         .mmap_file =                    selinux_mmap_file,
5916         .mmap_addr =                    selinux_mmap_addr,
5917         .file_mprotect =                selinux_file_mprotect,
5918         .file_lock =                    selinux_file_lock,
5919         .file_fcntl =                   selinux_file_fcntl,
5920         .file_set_fowner =              selinux_file_set_fowner,
5921         .file_send_sigiotask =          selinux_file_send_sigiotask,
5922         .file_receive =                 selinux_file_receive,
5923
5924         .file_open =                    selinux_file_open,
5925
5926         .task_create =                  selinux_task_create,
5927         .cred_alloc_blank =             selinux_cred_alloc_blank,
5928         .cred_free =                    selinux_cred_free,
5929         .cred_prepare =                 selinux_cred_prepare,
5930         .cred_transfer =                selinux_cred_transfer,
5931         .kernel_act_as =                selinux_kernel_act_as,
5932         .kernel_create_files_as =       selinux_kernel_create_files_as,
5933         .kernel_module_request =        selinux_kernel_module_request,
5934         .task_setpgid =                 selinux_task_setpgid,
5935         .task_getpgid =                 selinux_task_getpgid,
5936         .task_getsid =                  selinux_task_getsid,
5937         .task_getsecid =                selinux_task_getsecid,
5938         .task_setnice =                 selinux_task_setnice,
5939         .task_setioprio =               selinux_task_setioprio,
5940         .task_getioprio =               selinux_task_getioprio,
5941         .task_setrlimit =               selinux_task_setrlimit,
5942         .task_setscheduler =            selinux_task_setscheduler,
5943         .task_getscheduler =            selinux_task_getscheduler,
5944         .task_movememory =              selinux_task_movememory,
5945         .task_kill =                    selinux_task_kill,
5946         .task_wait =                    selinux_task_wait,
5947         .task_to_inode =                selinux_task_to_inode,
5948
5949         .ipc_permission =               selinux_ipc_permission,
5950         .ipc_getsecid =                 selinux_ipc_getsecid,
5951
5952         .msg_msg_alloc_security =       selinux_msg_msg_alloc_security,
5953         .msg_msg_free_security =        selinux_msg_msg_free_security,
5954
5955         .msg_queue_alloc_security =     selinux_msg_queue_alloc_security,
5956         .msg_queue_free_security =      selinux_msg_queue_free_security,
5957         .msg_queue_associate =          selinux_msg_queue_associate,
5958         .msg_queue_msgctl =             selinux_msg_queue_msgctl,
5959         .msg_queue_msgsnd =             selinux_msg_queue_msgsnd,
5960         .msg_queue_msgrcv =             selinux_msg_queue_msgrcv,
5961
5962         .shm_alloc_security =           selinux_shm_alloc_security,
5963         .shm_free_security =            selinux_shm_free_security,
5964         .shm_associate =                selinux_shm_associate,
5965         .shm_shmctl =                   selinux_shm_shmctl,
5966         .shm_shmat =                    selinux_shm_shmat,
5967
5968         .sem_alloc_security =           selinux_sem_alloc_security,
5969         .sem_free_security =            selinux_sem_free_security,
5970         .sem_associate =                selinux_sem_associate,
5971         .sem_semctl =                   selinux_sem_semctl,
5972         .sem_semop =                    selinux_sem_semop,
5973
5974         .d_instantiate =                selinux_d_instantiate,
5975
5976         .getprocattr =                  selinux_getprocattr,
5977         .setprocattr =                  selinux_setprocattr,
5978
5979         .ismaclabel =                   selinux_ismaclabel,
5980         .secid_to_secctx =              selinux_secid_to_secctx,
5981         .secctx_to_secid =              selinux_secctx_to_secid,
5982         .release_secctx =               selinux_release_secctx,
5983         .inode_notifysecctx =           selinux_inode_notifysecctx,
5984         .inode_setsecctx =              selinux_inode_setsecctx,
5985         .inode_getsecctx =              selinux_inode_getsecctx,
5986
5987         .unix_stream_connect =          selinux_socket_unix_stream_connect,
5988         .unix_may_send =                selinux_socket_unix_may_send,
5989
5990         .socket_create =                selinux_socket_create,
5991         .socket_post_create =           selinux_socket_post_create,
5992         .socket_bind =                  selinux_socket_bind,
5993         .socket_connect =               selinux_socket_connect,
5994         .socket_listen =                selinux_socket_listen,
5995         .socket_accept =                selinux_socket_accept,
5996         .socket_sendmsg =               selinux_socket_sendmsg,
5997         .socket_recvmsg =               selinux_socket_recvmsg,
5998         .socket_getsockname =           selinux_socket_getsockname,
5999         .socket_getpeername =           selinux_socket_getpeername,
6000         .socket_getsockopt =            selinux_socket_getsockopt,
6001         .socket_setsockopt =            selinux_socket_setsockopt,
6002         .socket_shutdown =              selinux_socket_shutdown,
6003         .socket_sock_rcv_skb =          selinux_socket_sock_rcv_skb,
6004         .socket_getpeersec_stream =     selinux_socket_getpeersec_stream,
6005         .socket_getpeersec_dgram =      selinux_socket_getpeersec_dgram,
6006         .sk_alloc_security =            selinux_sk_alloc_security,
6007         .sk_free_security =             selinux_sk_free_security,
6008         .sk_clone_security =            selinux_sk_clone_security,
6009         .sk_getsecid =                  selinux_sk_getsecid,
6010         .sock_graft =                   selinux_sock_graft,
6011         .inet_conn_request =            selinux_inet_conn_request,
6012         .inet_csk_clone =               selinux_inet_csk_clone,
6013         .inet_conn_established =        selinux_inet_conn_established,
6014         .secmark_relabel_packet =       selinux_secmark_relabel_packet,
6015         .secmark_refcount_inc =         selinux_secmark_refcount_inc,
6016         .secmark_refcount_dec =         selinux_secmark_refcount_dec,
6017         .req_classify_flow =            selinux_req_classify_flow,
6018         .tun_dev_alloc_security =       selinux_tun_dev_alloc_security,
6019         .tun_dev_free_security =        selinux_tun_dev_free_security,
6020         .tun_dev_create =               selinux_tun_dev_create,
6021         .tun_dev_attach_queue =         selinux_tun_dev_attach_queue,
6022         .tun_dev_attach =               selinux_tun_dev_attach,
6023         .tun_dev_open =                 selinux_tun_dev_open,
6024
6025 #ifdef CONFIG_SECURITY_NETWORK_XFRM
6026         .xfrm_policy_alloc_security =   selinux_xfrm_policy_alloc,
6027         .xfrm_policy_clone_security =   selinux_xfrm_policy_clone,
6028         .xfrm_policy_free_security =    selinux_xfrm_policy_free,
6029         .xfrm_policy_delete_security =  selinux_xfrm_policy_delete,
6030         .xfrm_state_alloc =             selinux_xfrm_state_alloc,
6031         .xfrm_state_alloc_acquire =     selinux_xfrm_state_alloc_acquire,
6032         .xfrm_state_free_security =     selinux_xfrm_state_free,
6033         .xfrm_state_delete_security =   selinux_xfrm_state_delete,
6034         .xfrm_policy_lookup =           selinux_xfrm_policy_lookup,
6035         .xfrm_state_pol_flow_match =    selinux_xfrm_state_pol_flow_match,
6036         .xfrm_decode_session =          selinux_xfrm_decode_session,
6037 #endif
6038
6039 #ifdef CONFIG_KEYS
6040         .key_alloc =                    selinux_key_alloc,
6041         .key_free =                     selinux_key_free,
6042         .key_permission =               selinux_key_permission,
6043         .key_getsecurity =              selinux_key_getsecurity,
6044 #endif
6045
6046 #ifdef CONFIG_AUDIT
6047         .audit_rule_init =              selinux_audit_rule_init,
6048         .audit_rule_known =             selinux_audit_rule_known,
6049         .audit_rule_match =             selinux_audit_rule_match,
6050         .audit_rule_free =              selinux_audit_rule_free,
6051 #endif
6052 };
6053
6054 static __init int selinux_init(void)
6055 {
6056         if (!security_module_enable(&selinux_ops)) {
6057                 selinux_enabled = 0;
6058                 return 0;
6059         }
6060
6061         if (!selinux_enabled) {
6062                 printk(KERN_INFO "SELinux:  Disabled at boot.\n");
6063                 return 0;
6064         }
6065
6066         printk(KERN_INFO "SELinux:  Initializing.\n");
6067
6068         /* Set the security state for the initial task. */
6069         cred_init_security();
6070
6071         default_noexec = !(VM_DATA_DEFAULT_FLAGS & VM_EXEC);
6072
6073         sel_inode_cache = kmem_cache_create("selinux_inode_security",
6074                                             sizeof(struct inode_security_struct),
6075                                             0, SLAB_PANIC, NULL);
6076         avc_init();
6077
6078         if (register_security(&selinux_ops))
6079                 panic("SELinux: Unable to register with kernel.\n");
6080
6081         if (avc_add_callback(selinux_netcache_avc_callback, AVC_CALLBACK_RESET))
6082                 panic("SELinux: Unable to register AVC netcache callback\n");
6083
6084         if (selinux_enforcing)
6085                 printk(KERN_DEBUG "SELinux:  Starting in enforcing mode\n");
6086         else
6087                 printk(KERN_DEBUG "SELinux:  Starting in permissive mode\n");
6088
6089         return 0;
6090 }
6091
6092 static void delayed_superblock_init(struct super_block *sb, void *unused)
6093 {
6094         superblock_doinit(sb, NULL);
6095 }
6096
6097 void selinux_complete_init(void)
6098 {
6099         printk(KERN_DEBUG "SELinux:  Completing initialization.\n");
6100
6101         /* Set up any superblocks initialized prior to the policy load. */
6102         printk(KERN_DEBUG "SELinux:  Setting up existing superblocks.\n");
6103         iterate_supers(delayed_superblock_init, NULL);
6104 }
6105
6106 /* SELinux requires early initialization in order to label
6107    all processes and objects when they are created. */
6108 security_initcall(selinux_init);
6109
6110 #if defined(CONFIG_NETFILTER)
6111
6112 static struct nf_hook_ops selinux_nf_ops[] = {
6113         {
6114                 .hook =         selinux_ipv4_postroute,
6115                 .owner =        THIS_MODULE,
6116                 .pf =           NFPROTO_IPV4,
6117                 .hooknum =      NF_INET_POST_ROUTING,
6118                 .priority =     NF_IP_PRI_SELINUX_LAST,
6119         },
6120         {
6121                 .hook =         selinux_ipv4_forward,
6122                 .owner =        THIS_MODULE,
6123                 .pf =           NFPROTO_IPV4,
6124                 .hooknum =      NF_INET_FORWARD,
6125                 .priority =     NF_IP_PRI_SELINUX_FIRST,
6126         },
6127         {
6128                 .hook =         selinux_ipv4_output,
6129                 .owner =        THIS_MODULE,
6130                 .pf =           NFPROTO_IPV4,
6131                 .hooknum =      NF_INET_LOCAL_OUT,
6132                 .priority =     NF_IP_PRI_SELINUX_FIRST,
6133         },
6134 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
6135         {
6136                 .hook =         selinux_ipv6_postroute,
6137                 .owner =        THIS_MODULE,
6138                 .pf =           NFPROTO_IPV6,
6139                 .hooknum =      NF_INET_POST_ROUTING,
6140                 .priority =     NF_IP6_PRI_SELINUX_LAST,
6141         },
6142         {
6143                 .hook =         selinux_ipv6_forward,
6144                 .owner =        THIS_MODULE,
6145                 .pf =           NFPROTO_IPV6,
6146                 .hooknum =      NF_INET_FORWARD,
6147                 .priority =     NF_IP6_PRI_SELINUX_FIRST,
6148         },
6149 #endif  /* IPV6 */
6150 };
6151
6152 static int __init selinux_nf_ip_init(void)
6153 {
6154         int err;
6155
6156         if (!selinux_enabled)
6157                 return 0;
6158
6159         printk(KERN_DEBUG "SELinux:  Registering netfilter hooks\n");
6160
6161         err = nf_register_hooks(selinux_nf_ops, ARRAY_SIZE(selinux_nf_ops));
6162         if (err)
6163                 panic("SELinux: nf_register_hooks: error %d\n", err);
6164
6165         return 0;
6166 }
6167
6168 __initcall(selinux_nf_ip_init);
6169
6170 #ifdef CONFIG_SECURITY_SELINUX_DISABLE
6171 static void selinux_nf_ip_exit(void)
6172 {
6173         printk(KERN_DEBUG "SELinux:  Unregistering netfilter hooks\n");
6174
6175         nf_unregister_hooks(selinux_nf_ops, ARRAY_SIZE(selinux_nf_ops));
6176 }
6177 #endif
6178
6179 #else /* CONFIG_NETFILTER */
6180
6181 #ifdef CONFIG_SECURITY_SELINUX_DISABLE
6182 #define selinux_nf_ip_exit()
6183 #endif
6184
6185 #endif /* CONFIG_NETFILTER */
6186
6187 #ifdef CONFIG_SECURITY_SELINUX_DISABLE
6188 static int selinux_disabled;
6189
6190 int selinux_disable(void)
6191 {
6192         if (ss_initialized) {
6193                 /* Not permitted after initial policy load. */
6194                 return -EINVAL;
6195         }
6196
6197         if (selinux_disabled) {
6198                 /* Only do this once. */
6199                 return -EINVAL;
6200         }
6201
6202         printk(KERN_INFO "SELinux:  Disabled at runtime.\n");
6203
6204         selinux_disabled = 1;
6205         selinux_enabled = 0;
6206
6207         reset_security_ops();
6208
6209         /* Try to destroy the avc node cache */
6210         avc_disable();
6211
6212         /* Unregister netfilter hooks. */
6213         selinux_nf_ip_exit();
6214
6215         /* Unregister selinuxfs. */
6216         exit_sel_fs();
6217
6218         return 0;
6219 }
6220 #endif