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 Red Hat, Inc., James Morris <jmorris@redhat.com>
  13  *  Copyright (C) 2004-2005 Trusted Computer Solutions, Inc.
  14  *                          <dgoeddel@trustedcs.com>
  15  *  Copyright (C) 2006, 2007 Hewlett-Packard Development Company, L.P.
  16  *                Paul Moore <paul.moore@hp.com>
  17  *  Copyright (C) 2007 Hitachi Software Engineering Co., Ltd.
  18  *                     Yuichi Nakamura <ynakam@hitachisoft.jp>
  19  *
  20  *      This program is free software; you can redistribute it and/or modify
  21  *      it under the terms of the GNU General Public License version 2,
  22  *      as published by the Free Software Foundation.
  23  */
  24
  25 #include <linux/init.h>
  26 #include <linux/kernel.h>
  27 #include <linux/ptrace.h>
  28 #include <linux/errno.h>
  29 #include <linux/sched.h>
  30 #include <linux/security.h>
  31 #include <linux/xattr.h>
  32 #include <linux/capability.h>
  33 #include <linux/unistd.h>
  34 #include <linux/mm.h>
  35 #include <linux/mman.h>
  36 #include <linux/slab.h>
  37 #include <linux/pagemap.h>
  38 #include <linux/swap.h>
  39 #include <linux/spinlock.h>
  40 #include <linux/syscalls.h>
  41 #include <linux/file.h>
  42 #include <linux/namei.h>
  43 #include <linux/mount.h>
  44 #include <linux/ext2_fs.h>
  45 #include <linux/proc_fs.h>
  46 #include <linux/kd.h>
  47 #include <linux/netfilter_ipv4.h>
  48 #include <linux/netfilter_ipv6.h>
  49 #include <linux/tty.h>
  50 #include <net/icmp.h>
  51 #include <net/ip.h>             /* for local_port_range[] */
  52 #include <net/tcp.h>            /* struct or_callable used in sock_rcv_skb */
  53 #include <net/net_namespace.h>
  54 #include <net/netlabel.h>
  55 #include <asm/uaccess.h>
  56 #include <asm/ioctls.h>
  57 #include <asm/atomic.h>
  58 #include <linux/bitops.h>
  59 #include <linux/interrupt.h>
  60 #include <linux/netdevice.h>    /* for network interface checks */
  61 #include <linux/netlink.h>
  62 #include <linux/tcp.h>
  63 #include <linux/udp.h>
  64 #include <linux/dccp.h>
  65 #include <linux/quota.h>
  66 #include <linux/un.h>           /* for Unix socket types */
  67 #include <net/af_unix.h>        /* for Unix socket types */
  68 #include <linux/parser.h>
  69 #include <linux/nfs_mount.h>
  70 #include <net/ipv6.h>
  71 #include <linux/hugetlb.h>
  72 #include <linux/personality.h>
  73 #include <linux/sysctl.h>
  74 #include <linux/audit.h>
  75 #include <linux/string.h>
  76 #include <linux/selinux.h>
  77 #include <linux/mutex.h>
  78
  79 #include "avc.h"
  80 #include "objsec.h"
  81 #include "netif.h"
  82 #include "netnode.h"
  83 #include "xfrm.h"
  84 #include "netlabel.h"
  85
  86 #define XATTR_SELINUX_SUFFIX "selinux"
  87 #define XATTR_NAME_SELINUX XATTR_SECURITY_PREFIX XATTR_SELINUX_SUFFIX
  88
  89 #define NUM_SEL_MNT_OPTS 4
  90
  91 extern unsigned int policydb_loaded_version;
  92 extern int selinux_nlmsg_lookup(u16 sclass, u16 nlmsg_type, u32 *perm);
  93 extern int selinux_compat_net;
  94 extern struct security_operations *security_ops;
  95
  96 /* SECMARK reference count */
  97 atomic_t selinux_secmark_refcount = ATOMIC_INIT(0);
  98
  99 #ifdef CONFIG_SECURITY_SELINUX_DEVELOP
 100 int selinux_enforcing = 0;
 101
 102 static int __init enforcing_setup(char *str)
 103 {
 104         selinux_enforcing = simple_strtol(str,NULL,0);
 105         return 1;
 106 }
 107 __setup("enforcing=", enforcing_setup);
 108 #endif
 109
 110 #ifdef CONFIG_SECURITY_SELINUX_BOOTPARAM
 111 int selinux_enabled = CONFIG_SECURITY_SELINUX_BOOTPARAM_VALUE;
 112
 113 static int __init selinux_enabled_setup(char *str)
 114 {
 115         selinux_enabled = simple_strtol(str, NULL, 0);
 116         return 1;
 117 }
 118 __setup("selinux=", selinux_enabled_setup);
 119 #else
 120 int selinux_enabled = 1;
 121 #endif
 122
 123 /* Original (dummy) security module. */
 124 static struct security_operations *original_ops = NULL;
 125
 126 /* Minimal support for a secondary security module,
 127    just to allow the use of the dummy or capability modules.
 128    The owlsm module can alternatively be used as a secondary
 129    module as long as CONFIG_OWLSM_FD is not enabled. */
 130 static struct security_operations *secondary_ops = NULL;
 131
 132 /* Lists of inode and superblock security structures initialized
 133    before the policy was loaded. */
 134 static LIST_HEAD(superblock_security_head);
 135 static DEFINE_SPINLOCK(sb_security_lock);
 136
 137 static struct kmem_cache *sel_inode_cache;
 138
 139 /**
 140  * selinux_secmark_enabled - Check to see if SECMARK is currently enabled
 141  *
 142  * Description:
 143  * This function checks the SECMARK reference counter to see if any SECMARK
 144  * targets are currently configured, if the reference counter is greater than
 145  * zero SECMARK is considered to be enabled.  Returns true (1) if SECMARK is
 146  * enabled, false (0) if SECMARK is disabled.
 147  *
 148  */
 149 static int selinux_secmark_enabled(void)
 150 {
 151         return (atomic_read(&selinux_secmark_refcount) > 0);
 152 }
 153
 154 /* Allocate and free functions for each kind of security blob. */
 155
 156 static int task_alloc_security(struct task_struct *task)
 157 {
 158         struct task_security_struct *tsec;
 159
 160         tsec = kzalloc(sizeof(struct task_security_struct), GFP_KERNEL);
 161         if (!tsec)
 162                 return -ENOMEM;
 163
 164         tsec->task = task;
 165         tsec->osid = tsec->sid = tsec->ptrace_sid = SECINITSID_UNLABELED;
 166         task->security = tsec;
 167
 168         return 0;
 169 }
 170
 171 static void task_free_security(struct task_struct *task)
 172 {
 173         struct task_security_struct *tsec = task->security;
 174         task->security = NULL;
 175         kfree(tsec);
 176 }
 177
 178 static int inode_alloc_security(struct inode *inode)
 179 {
 180         struct task_security_struct *tsec = current->security;
 181         struct inode_security_struct *isec;
 182
 183         isec = kmem_cache_zalloc(sel_inode_cache, GFP_KERNEL);
 184         if (!isec)
 185                 return -ENOMEM;
 186
 187         mutex_init(&isec->lock);
 188         INIT_LIST_HEAD(&isec->list);
 189         isec->inode = inode;
 190         isec->sid = SECINITSID_UNLABELED;
 191         isec->sclass = SECCLASS_FILE;
 192         isec->task_sid = tsec->sid;
 193         inode->i_security = isec;
 194
 195         return 0;
 196 }
 197
 198 static void inode_free_security(struct inode *inode)
 199 {
 200         struct inode_security_struct *isec = inode->i_security;
 201         struct superblock_security_struct *sbsec = inode->i_sb->s_security;
 202
 203         spin_lock(&sbsec->isec_lock);
 204         if (!list_empty(&isec->list))
 205                 list_del_init(&isec->list);
 206         spin_unlock(&sbsec->isec_lock);
 207
 208         inode->i_security = NULL;
 209         kmem_cache_free(sel_inode_cache, isec);
 210 }
 211
 212 static int file_alloc_security(struct file *file)
 213 {
 214         struct task_security_struct *tsec = current->security;
 215         struct file_security_struct *fsec;
 216
 217         fsec = kzalloc(sizeof(struct file_security_struct), GFP_KERNEL);
 218         if (!fsec)
 219                 return -ENOMEM;
 220
 221         fsec->file = file;
 222         fsec->sid = tsec->sid;
 223         fsec->fown_sid = tsec->sid;
 224         file->f_security = fsec;
 225
 226         return 0;
 227 }
 228
 229 static void file_free_security(struct file *file)
 230 {
 231         struct file_security_struct *fsec = file->f_security;
 232         file->f_security = NULL;
 233         kfree(fsec);
 234 }
 235
 236 static int superblock_alloc_security(struct super_block *sb)
 237 {
 238         struct superblock_security_struct *sbsec;
 239
 240         sbsec = kzalloc(sizeof(struct superblock_security_struct), GFP_KERNEL);
 241         if (!sbsec)
 242                 return -ENOMEM;
 243
 244         mutex_init(&sbsec->lock);
 245         INIT_LIST_HEAD(&sbsec->list);
 246         INIT_LIST_HEAD(&sbsec->isec_head);
 247         spin_lock_init(&sbsec->isec_lock);
 248         sbsec->sb = sb;
 249         sbsec->sid = SECINITSID_UNLABELED;
 250         sbsec->def_sid = SECINITSID_FILE;
 251         sbsec->mntpoint_sid = SECINITSID_UNLABELED;
 252         sb->s_security = sbsec;
 253
 254         return 0;
 255 }
 256
 257 static void superblock_free_security(struct super_block *sb)
 258 {
 259         struct superblock_security_struct *sbsec = sb->s_security;
 260
 261         spin_lock(&sb_security_lock);
 262         if (!list_empty(&sbsec->list))
 263                 list_del_init(&sbsec->list);
 264         spin_unlock(&sb_security_lock);
 265
 266         sb->s_security = NULL;
 267         kfree(sbsec);
 268 }
 269
 270 static int sk_alloc_security(struct sock *sk, int family, gfp_t priority)
 271 {
 272         struct sk_security_struct *ssec;
 273
 274         ssec = kzalloc(sizeof(*ssec), priority);
 275         if (!ssec)
 276                 return -ENOMEM;
 277
 278         ssec->sk = sk;
 279         ssec->peer_sid = SECINITSID_UNLABELED;
 280         ssec->sid = SECINITSID_UNLABELED;
 281         sk->sk_security = ssec;
 282
 283         selinux_netlbl_sk_security_init(ssec, family);
 284
 285         return 0;
 286 }
 287
 288 static void sk_free_security(struct sock *sk)
 289 {
 290         struct sk_security_struct *ssec = sk->sk_security;
 291
 292         sk->sk_security = NULL;
 293         kfree(ssec);
 294 }
 295
 296 /* The security server must be initialized before
 297    any labeling or access decisions can be provided. */
 298 extern int ss_initialized;
 299
 300 /* The file system's label must be initialized prior to use. */
 301
 302 static char *labeling_behaviors[6] = {
 303         "uses xattr",
 304         "uses transition SIDs",
 305         "uses task SIDs",
 306         "uses genfs_contexts",
 307         "not configured for labeling",
 308         "uses mountpoint labeling",
 309 };
 310
 311 static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dentry);
 312
 313 static inline int inode_doinit(struct inode *inode)
 314 {
 315         return inode_doinit_with_dentry(inode, NULL);
 316 }
 317
 318 enum {
 319         Opt_error = -1,
 320         Opt_context = 1,
 321         Opt_fscontext = 2,
 322         Opt_defcontext = 3,
 323         Opt_rootcontext = 4,
 324 };
 325
 326 static match_table_t tokens = {
 327         {Opt_context, "context=%s"},
 328         {Opt_fscontext, "fscontext=%s"},
 329         {Opt_defcontext, "defcontext=%s"},
 330         {Opt_rootcontext, "rootcontext=%s"},
 331         {Opt_error, NULL},
 332 };
 333
 334 #define SEL_MOUNT_FAIL_MSG "SELinux:  duplicate or incompatible mount options\n"
 335
 336 static int may_context_mount_sb_relabel(u32 sid,
 337                         struct superblock_security_struct *sbsec,
 338                         struct task_security_struct *tsec)
 339 {
 340         int rc;
 341
 342         rc = avc_has_perm(tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM,
 343                           FILESYSTEM__RELABELFROM, NULL);
 344         if (rc)
 345                 return rc;
 346
 347         rc = avc_has_perm(tsec->sid, sid, SECCLASS_FILESYSTEM,
 348                           FILESYSTEM__RELABELTO, NULL);
 349         return rc;
 350 }
 351
 352 static int may_context_mount_inode_relabel(u32 sid,
 353                         struct superblock_security_struct *sbsec,
 354                         struct task_security_struct *tsec)
 355 {
 356         int rc;
 357         rc = avc_has_perm(tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM,
 358                           FILESYSTEM__RELABELFROM, NULL);
 359         if (rc)
 360                 return rc;
 361
 362         rc = avc_has_perm(sid, sbsec->sid, SECCLASS_FILESYSTEM,
 363                           FILESYSTEM__ASSOCIATE, NULL);
 364         return rc;
 365 }
 366
 367 static int sb_finish_set_opts(struct super_block *sb)
 368 {
 369         struct superblock_security_struct *sbsec = sb->s_security;
 370         struct dentry *root = sb->s_root;
 371         struct inode *root_inode = root->d_inode;
 372         int rc = 0;
 373
 374         if (sbsec->behavior == SECURITY_FS_USE_XATTR) {
 375                 /* Make sure that the xattr handler exists and that no
 376                    error other than -ENODATA is returned by getxattr on
 377                    the root directory.  -ENODATA is ok, as this may be
 378                    the first boot of the SELinux kernel before we have
 379                    assigned xattr values to the filesystem. */
 380                 if (!root_inode->i_op->getxattr) {
 381                         printk(KERN_WARNING "SELinux: (dev %s, type %s) has no "
 382                                "xattr support\n", sb->s_id, sb->s_type->name);
 383                         rc = -EOPNOTSUPP;
 384                         goto out;
 385                 }
 386                 rc = root_inode->i_op->getxattr(root, XATTR_NAME_SELINUX, NULL, 0);
 387                 if (rc < 0 && rc != -ENODATA) {
 388                         if (rc == -EOPNOTSUPP)
 389                                 printk(KERN_WARNING "SELinux: (dev %s, type "
 390                                        "%s) has no security xattr handler\n",
 391                                        sb->s_id, sb->s_type->name);
 392                         else
 393                                 printk(KERN_WARNING "SELinux: (dev %s, type "
 394                                        "%s) getxattr errno %d\n", sb->s_id,
 395                                        sb->s_type->name, -rc);
 396                         goto out;
 397                 }
 398         }
 399
 400         sbsec->initialized = 1;
 401
 402         if (sbsec->behavior > ARRAY_SIZE(labeling_behaviors))
 403                 printk(KERN_ERR "SELinux: initialized (dev %s, type %s), unknown behavior\n",
 404                        sb->s_id, sb->s_type->name);
 405         else
 406                 printk(KERN_DEBUG "SELinux: initialized (dev %s, type %s), %s\n",
 407                        sb->s_id, sb->s_type->name,
 408                        labeling_behaviors[sbsec->behavior-1]);
 409
 410         /* Initialize the root inode. */
 411         rc = inode_doinit_with_dentry(root_inode, root);
 412
 413         /* Initialize any other inodes associated with the superblock, e.g.
 414            inodes created prior to initial policy load or inodes created
 415            during get_sb by a pseudo filesystem that directly
 416            populates itself. */
 417         spin_lock(&sbsec->isec_lock);
 418 next_inode:
 419         if (!list_empty(&sbsec->isec_head)) {
 420                 struct inode_security_struct *isec =
 421                                 list_entry(sbsec->isec_head.next,
 422                                            struct inode_security_struct, list);
 423                 struct inode *inode = isec->inode;
 424                 spin_unlock(&sbsec->isec_lock);
 425                 inode = igrab(inode);
 426                 if (inode) {
 427                         if (!IS_PRIVATE(inode))
 428                                 inode_doinit(inode);
 429                         iput(inode);
 430                 }
 431                 spin_lock(&sbsec->isec_lock);
 432                 list_del_init(&isec->list);
 433                 goto next_inode;
 434         }
 435         spin_unlock(&sbsec->isec_lock);
 436 out:
 437         return rc;
 438 }
 439
 440 /*
 441  * This function should allow an FS to ask what it's mount security
 442  * options were so it can use those later for submounts, displaying
 443  * mount options, or whatever.
 444  */
 445 static int selinux_get_mnt_opts(const struct super_block *sb,
 446                                 char ***mount_options, int **mnt_opts_flags,
 447                                 int *num_opts)
 448 {
 449         int rc = 0, i;
 450         struct superblock_security_struct *sbsec = sb->s_security;
 451         char *context = NULL;
 452         u32 len;
 453         char tmp;
 454
 455         *num_opts = 0;
 456         *mount_options = NULL;
 457         *mnt_opts_flags = NULL;
 458
 459         if (!sbsec->initialized)
 460                 return -EINVAL;
 461
 462         if (!ss_initialized)
 463                 return -EINVAL;
 464
 465         /*
 466          * if we ever use sbsec flags for anything other than tracking mount
 467          * settings this is going to need a mask
 468          */
 469         tmp = sbsec->flags;
 470         /* count the number of mount options for this sb */
 471         for (i = 0; i < 8; i++) {
 472                 if (tmp & 0x01)
 473                         (*num_opts)++;
 474                 tmp >>= 1;
 475         }
 476
 477         *mount_options = kcalloc(*num_opts, sizeof(char *), GFP_ATOMIC);
 478         if (!*mount_options) {
 479                 rc = -ENOMEM;
 480                 goto out_free;
 481         }
 482
 483         *mnt_opts_flags = kcalloc(*num_opts, sizeof(int), GFP_ATOMIC);
 484         if (!*mnt_opts_flags) {
 485                 rc = -ENOMEM;
 486                 goto out_free;
 487         }
 488
 489         i = 0;
 490         if (sbsec->flags & FSCONTEXT_MNT) {
 491                 rc = security_sid_to_context(sbsec->sid, &context, &len);
 492                 if (rc)
 493                         goto out_free;
 494                 (*mount_options)[i] = context;
 495                 (*mnt_opts_flags)[i++] = FSCONTEXT_MNT;
 496         }
 497         if (sbsec->flags & CONTEXT_MNT) {
 498                 rc = security_sid_to_context(sbsec->mntpoint_sid, &context, &len);
 499                 if (rc)
 500                         goto out_free;
 501                 (*mount_options)[i] = context;
 502                 (*mnt_opts_flags)[i++] = CONTEXT_MNT;
 503         }
 504         if (sbsec->flags & DEFCONTEXT_MNT) {
 505                 rc = security_sid_to_context(sbsec->def_sid, &context, &len);
 506                 if (rc)
 507                         goto out_free;
 508                 (*mount_options)[i] = context;
 509                 (*mnt_opts_flags)[i++] = DEFCONTEXT_MNT;
 510         }
 511         if (sbsec->flags & ROOTCONTEXT_MNT) {
 512                 struct inode *root = sbsec->sb->s_root->d_inode;
 513                 struct inode_security_struct *isec = root->i_security;
 514
 515                 rc = security_sid_to_context(isec->sid, &context, &len);
 516                 if (rc)
 517                         goto out_free;
 518                 (*mount_options)[i] = context;
 519                 (*mnt_opts_flags)[i++] = ROOTCONTEXT_MNT;
 520         }
 521
 522         BUG_ON(i != *num_opts);
 523
 524         return 0;
 525
 526 out_free:
 527         /* don't leak context string if security_sid_to_context had an error */
 528         if (*mount_options && i)
 529                 for (; i > 0; i--)
 530                         kfree((*mount_options)[i-1]);
 531         kfree(*mount_options);
 532         *mount_options = NULL;
 533         kfree(*mnt_opts_flags);
 534         *mnt_opts_flags = NULL;
 535         *num_opts = 0;
 536         return rc;
 537 }
 538
 539 static int bad_option(struct superblock_security_struct *sbsec, char flag,
 540                       u32 old_sid, u32 new_sid)
 541 {
 542         /* check if the old mount command had the same options */
 543         if (sbsec->initialized)
 544                 if (!(sbsec->flags & flag) ||
 545                     (old_sid != new_sid))
 546                         return 1;
 547
 548         /* check if we were passed the same options twice,
 549          * aka someone passed context=a,context=b
 550          */
 551         if (!sbsec->initialized)
 552                 if (sbsec->flags & flag)
 553                         return 1;
 554         return 0;
 555 }
 556 /*
 557  * Allow filesystems with binary mount data to explicitly set mount point
 558  * labeling information.
 559  */
 560 static int selinux_set_mnt_opts(struct super_block *sb, char **mount_options,
 561                                 int *flags, int num_opts)
 562 {
 563         int rc = 0, i;
 564         struct task_security_struct *tsec = current->security;
 565         struct superblock_security_struct *sbsec = sb->s_security;
 566         const char *name = sb->s_type->name;
 567         struct inode *inode = sbsec->sb->s_root->d_inode;
 568         struct inode_security_struct *root_isec = inode->i_security;
 569         u32 fscontext_sid = 0, context_sid = 0, rootcontext_sid = 0;
 570         u32 defcontext_sid = 0;
 571
 572         mutex_lock(&sbsec->lock);
 573
 574         if (!ss_initialized) {
 575                 if (!num_opts) {
 576                         /* Defer initialization until selinux_complete_init,
 577                            after the initial policy is loaded and the security
 578                            server is ready to handle calls. */
 579                         spin_lock(&sb_security_lock);
 580                         if (list_empty(&sbsec->list))
 581                                 list_add(&sbsec->list, &superblock_security_head);
 582                         spin_unlock(&sb_security_lock);
 583                         goto out;
 584                 }
 585                 rc = -EINVAL;
 586                 printk(KERN_WARNING "Unable to set superblock options before "
 587                        "the security server is initialized\n");
 588                 goto out;
 589         }
 590
 591         /*
 592          * parse the mount options, check if they are valid sids.
 593          * also check if someone is trying to mount the same sb more
 594          * than once with different security options.
 595          */
 596         for (i = 0; i < num_opts; i++) {
 597                 u32 sid;
 598                 rc = security_context_to_sid(mount_options[i],
 599                                              strlen(mount_options[i]), &sid);
 600                 if (rc) {
 601                         printk(KERN_WARNING "SELinux: security_context_to_sid"
 602                                "(%s) failed for (dev %s, type %s) errno=%d\n",
 603                                mount_options[i], sb->s_id, name, rc);
 604                         goto out;
 605                 }
 606                 switch (flags[i]) {
 607                 case FSCONTEXT_MNT:
 608                         fscontext_sid = sid;
 609
 610                         if (bad_option(sbsec, FSCONTEXT_MNT, sbsec->sid,
 611                                         fscontext_sid))
 612                                 goto out_double_mount;
 613
 614                         sbsec->flags |= FSCONTEXT_MNT;
 615                         break;
 616                 case CONTEXT_MNT:
 617                         context_sid = sid;
 618
 619                         if (bad_option(sbsec, CONTEXT_MNT, sbsec->mntpoint_sid,
 620                                         context_sid))
 621                                 goto out_double_mount;
 622
 623                         sbsec->flags |= CONTEXT_MNT;
 624                         break;
 625                 case ROOTCONTEXT_MNT:
 626                         rootcontext_sid = sid;
 627
 628                         if (bad_option(sbsec, ROOTCONTEXT_MNT, root_isec->sid,
 629                                         rootcontext_sid))
 630                                 goto out_double_mount;
 631
 632                         sbsec->flags |= ROOTCONTEXT_MNT;
 633
 634                         break;
 635                 case DEFCONTEXT_MNT:
 636                         defcontext_sid = sid;
 637
 638                         if (bad_option(sbsec, DEFCONTEXT_MNT, sbsec->def_sid,
 639                                         defcontext_sid))
 640                                 goto out_double_mount;
 641
 642                         sbsec->flags |= DEFCONTEXT_MNT;
 643
 644                         break;
 645                 default:
 646                         rc = -EINVAL;
 647                         goto out;
 648                 }
 649         }
 650
 651         if (sbsec->initialized) {
 652                 /* previously mounted with options, but not on this attempt? */
 653                 if (sbsec->flags && !num_opts)
 654                         goto out_double_mount;
 655                 rc = 0;
 656                 goto out;
 657         }
 658
 659         if (strcmp(sb->s_type->name, "proc") == 0)
 660                 sbsec->proc = 1;
 661
 662         /* Determine the labeling behavior to use for this filesystem type. */
 663         rc = security_fs_use(sb->s_type->name, &sbsec->behavior, &sbsec->sid);
 664         if (rc) {
 665                 printk(KERN_WARNING "%s: security_fs_use(%s) returned %d\n",
 666                        __FUNCTION__, sb->s_type->name, rc);
 667                 goto out;
 668         }
 669
 670         /* sets the context of the superblock for the fs being mounted. */
 671         if (fscontext_sid) {
 672
 673                 rc = may_context_mount_sb_relabel(fscontext_sid, sbsec, tsec);
 674                 if (rc)
 675                         goto out;
 676
 677                 sbsec->sid = fscontext_sid;
 678         }
 679
 680         /*
 681          * Switch to using mount point labeling behavior.
 682          * sets the label used on all file below the mountpoint, and will set
 683          * the superblock context if not already set.
 684          */
 685         if (context_sid) {
 686                 if (!fscontext_sid) {
 687                         rc = may_context_mount_sb_relabel(context_sid, sbsec, tsec);
 688                         if (rc)
 689                                 goto out;
 690                         sbsec->sid = context_sid;
 691                 } else {
 692                         rc = may_context_mount_inode_relabel(context_sid, sbsec, tsec);
 693                         if (rc)
 694                                 goto out;
 695                 }
 696                 if (!rootcontext_sid)
 697                         rootcontext_sid = context_sid;
 698
 699                 sbsec->mntpoint_sid = context_sid;
 700                 sbsec->behavior = SECURITY_FS_USE_MNTPOINT;
 701         }
 702
 703         if (rootcontext_sid) {
 704                 rc = may_context_mount_inode_relabel(rootcontext_sid, sbsec, tsec);
 705                 if (rc)
 706                         goto out;
 707
 708                 root_isec->sid = rootcontext_sid;
 709                 root_isec->initialized = 1;
 710         }
 711
 712         if (defcontext_sid) {
 713                 if (sbsec->behavior != SECURITY_FS_USE_XATTR) {
 714                         rc = -EINVAL;
 715                         printk(KERN_WARNING "SELinux: defcontext option is "
 716                                "invalid for this filesystem type\n");
 717                         goto out;
 718                 }
 719
 720                 if (defcontext_sid != sbsec->def_sid) {
 721                         rc = may_context_mount_inode_relabel(defcontext_sid,
 722                                                              sbsec, tsec);
 723                         if (rc)
 724                                 goto out;
 725                 }
 726
 727                 sbsec->def_sid = defcontext_sid;
 728         }
 729
 730         rc = sb_finish_set_opts(sb);
 731 out:
 732         mutex_unlock(&sbsec->lock);
 733         return rc;
 734 out_double_mount:
 735         rc = -EINVAL;
 736         printk(KERN_WARNING "SELinux: mount invalid.  Same superblock, different "
 737                "security settings for (dev %s, type %s)\n", sb->s_id, name);
 738         goto out;
 739 }
 740
 741 static void selinux_sb_clone_mnt_opts(const struct super_block *oldsb,
 742                                         struct super_block *newsb)
 743 {
 744         const struct superblock_security_struct *oldsbsec = oldsb->s_security;
 745         struct superblock_security_struct *newsbsec = newsb->s_security;
 746
 747         int set_fscontext =     (oldsbsec->flags & FSCONTEXT_MNT);
 748         int set_context =       (oldsbsec->flags & CONTEXT_MNT);
 749         int set_rootcontext =   (oldsbsec->flags & ROOTCONTEXT_MNT);
 750
 751         /* we can't error, we can't save the info, this shouldn't get called
 752          * this early in the boot process. */
 753         BUG_ON(!ss_initialized);
 754
 755         /* this might go away sometime down the line if there is a new user
 756          * of clone, but for now, nfs better not get here... */
 757         BUG_ON(newsbsec->initialized);
 758
 759         /* how can we clone if the old one wasn't set up?? */
 760         BUG_ON(!oldsbsec->initialized);
 761
 762         mutex_lock(&newsbsec->lock);
 763
 764         newsbsec->flags = oldsbsec->flags;
 765
 766         newsbsec->sid = oldsbsec->sid;
 767         newsbsec->def_sid = oldsbsec->def_sid;
 768         newsbsec->behavior = oldsbsec->behavior;
 769
 770         if (set_context) {
 771                 u32 sid = oldsbsec->mntpoint_sid;
 772
 773                 if (!set_fscontext)
 774                         newsbsec->sid = sid;
 775                 if (!set_rootcontext) {
 776                         struct inode *newinode = newsb->s_root->d_inode;
 777                         struct inode_security_struct *newisec = newinode->i_security;
 778                         newisec->sid = sid;
 779                 }
 780                 newsbsec->mntpoint_sid = sid;
 781         }
 782         if (set_rootcontext) {
 783                 const struct inode *oldinode = oldsb->s_root->d_inode;
 784                 const struct inode_security_struct *oldisec = oldinode->i_security;
 785                 struct inode *newinode = newsb->s_root->d_inode;
 786                 struct inode_security_struct *newisec = newinode->i_security;
 787
 788                 newisec->sid = oldisec->sid;
 789         }
 790
 791         sb_finish_set_opts(newsb);
 792         mutex_unlock(&newsbsec->lock);
 793 }
 794
 795 /*
 796  * string mount options parsing and call set the sbsec
 797  */
 798 static int superblock_doinit(struct super_block *sb, void *data)
 799 {
 800         char *context = NULL, *defcontext = NULL;
 801         char *fscontext = NULL, *rootcontext = NULL;
 802         int rc = 0;
 803         char *p, *options = data;
 804         /* selinux only know about a fixed number of mount options */
 805         char *mnt_opts[NUM_SEL_MNT_OPTS];
 806         int mnt_opts_flags[NUM_SEL_MNT_OPTS], num_mnt_opts = 0;
 807
 808         if (!data)
 809                 goto out;
 810
 811         /* with the nfs patch this will become a goto out; */
 812         if (sb->s_type->fs_flags & FS_BINARY_MOUNTDATA) {
 813                 const char *name = sb->s_type->name;
 814                 /* NFS we understand. */
 815                 if (!strcmp(name, "nfs")) {
 816                         struct nfs_mount_data *d = data;
 817
 818                         if (d->version !=  NFS_MOUNT_VERSION)
 819                                 goto out;
 820
 821                         if (d->context[0]) {
 822                                 context = kstrdup(d->context, GFP_KERNEL);
 823                                 if (!context) {
 824                                         rc = -ENOMEM;
 825                                         goto out;
 826                                 }
 827                         }
 828                         goto build_flags;
 829                 } else
 830                         goto out;
 831         }
 832
 833         /* Standard string-based options. */
 834         while ((p = strsep(&options, "|")) != NULL) {
 835                 int token;
 836                 substring_t args[MAX_OPT_ARGS];
 837
 838                 if (!*p)
 839                         continue;
 840
 841                 token = match_token(p, tokens, args);
 842
 843                 switch (token) {
 844                 case Opt_context:
 845                         if (context || defcontext) {
 846                                 rc = -EINVAL;
 847                                 printk(KERN_WARNING SEL_MOUNT_FAIL_MSG);
 848                                 goto out_err;
 849                         }
 850                         context = match_strdup(&args[0]);
 851                         if (!context) {
 852                                 rc = -ENOMEM;
 853                                 goto out_err;
 854                         }
 855                         break;
 856
 857                 case Opt_fscontext:
 858                         if (fscontext) {
 859                                 rc = -EINVAL;
 860                                 printk(KERN_WARNING SEL_MOUNT_FAIL_MSG);
 861                                 goto out_err;
 862                         }
 863                         fscontext = match_strdup(&args[0]);
 864                         if (!fscontext) {
 865                                 rc = -ENOMEM;
 866                                 goto out_err;
 867                         }
 868                         break;
 869
 870                 case Opt_rootcontext:
 871                         if (rootcontext) {
 872                                 rc = -EINVAL;
 873                                 printk(KERN_WARNING SEL_MOUNT_FAIL_MSG);
 874                                 goto out_err;
 875                         }
 876                         rootcontext = match_strdup(&args[0]);
 877                         if (!rootcontext) {
 878                                 rc = -ENOMEM;
 879                                 goto out_err;
 880                         }
 881                         break;
 882
 883                 case Opt_defcontext:
 884                         if (context || defcontext) {
 885                                 rc = -EINVAL;
 886                                 printk(KERN_WARNING SEL_MOUNT_FAIL_MSG);
 887                                 goto out_err;
 888                         }
 889                         defcontext = match_strdup(&args[0]);
 890                         if (!defcontext) {
 891                                 rc = -ENOMEM;
 892                                 goto out_err;
 893                         }
 894                         break;
 895
 896                 default:
 897                         rc = -EINVAL;
 898                         printk(KERN_WARNING "SELinux:  unknown mount option\n");
 899                         goto out_err;
 900
 901                 }
 902         }
 903
 904 build_flags:
 905         if (fscontext) {
 906                 mnt_opts[num_mnt_opts] = fscontext;
 907                 mnt_opts_flags[num_mnt_opts++] = FSCONTEXT_MNT;
 908         }
 909         if (context) {
 910                 mnt_opts[num_mnt_opts] = context;
 911                 mnt_opts_flags[num_mnt_opts++] = CONTEXT_MNT;
 912         }
 913         if (rootcontext) {
 914                 mnt_opts[num_mnt_opts] = rootcontext;
 915                 mnt_opts_flags[num_mnt_opts++] = ROOTCONTEXT_MNT;
 916         }
 917         if (defcontext) {
 918                 mnt_opts[num_mnt_opts] = defcontext;
 919                 mnt_opts_flags[num_mnt_opts++] = DEFCONTEXT_MNT;
 920         }
 921
 922 out:
 923         rc = selinux_set_mnt_opts(sb, mnt_opts, mnt_opts_flags, num_mnt_opts);
 924 out_err:
 925         kfree(context);
 926         kfree(defcontext);
 927         kfree(fscontext);
 928         kfree(rootcontext);
 929         return rc;
 930 }
 931
 932 static inline u16 inode_mode_to_security_class(umode_t mode)
 933 {
 934         switch (mode & S_IFMT) {
 935         case S_IFSOCK:
 936                 return SECCLASS_SOCK_FILE;
 937         case S_IFLNK:
 938                 return SECCLASS_LNK_FILE;
 939         case S_IFREG:
 940                 return SECCLASS_FILE;
 941         case S_IFBLK:
 942                 return SECCLASS_BLK_FILE;
 943         case S_IFDIR:
 944                 return SECCLASS_DIR;
 945         case S_IFCHR:
 946                 return SECCLASS_CHR_FILE;
 947         case S_IFIFO:
 948                 return SECCLASS_FIFO_FILE;
 949
 950         }
 951
 952         return SECCLASS_FILE;
 953 }
 954
 955 static inline int default_protocol_stream(int protocol)
 956 {
 957         return (protocol == IPPROTO_IP || protocol == IPPROTO_TCP);
 958 }
 959
 960 static inline int default_protocol_dgram(int protocol)
 961 {
 962         return (protocol == IPPROTO_IP || protocol == IPPROTO_UDP);
 963 }
 964
 965 static inline u16 socket_type_to_security_class(int family, int type, int protocol)
 966 {
 967         switch (family) {
 968         case PF_UNIX:
 969                 switch (type) {
 970                 case SOCK_STREAM:
 971                 case SOCK_SEQPACKET:
 972                         return SECCLASS_UNIX_STREAM_SOCKET;
 973                 case SOCK_DGRAM:
 974                         return SECCLASS_UNIX_DGRAM_SOCKET;
 975                 }
 976                 break;
 977         case PF_INET:
 978         case PF_INET6:
 979                 switch (type) {
 980                 case SOCK_STREAM:
 981                         if (default_protocol_stream(protocol))
 982                                 return SECCLASS_TCP_SOCKET;
 983                         else
 984                                 return SECCLASS_RAWIP_SOCKET;
 985                 case SOCK_DGRAM:
 986                         if (default_protocol_dgram(protocol))
 987                                 return SECCLASS_UDP_SOCKET;
 988                         else
 989                                 return SECCLASS_RAWIP_SOCKET;
 990                 case SOCK_DCCP:
 991                         return SECCLASS_DCCP_SOCKET;
 992                 default:
 993                         return SECCLASS_RAWIP_SOCKET;
 994                 }
 995                 break;
 996         case PF_NETLINK:
 997                 switch (protocol) {
 998                 case NETLINK_ROUTE:
 999                         return SECCLASS_NETLINK_ROUTE_SOCKET;
1000                 case NETLINK_FIREWALL:
1001                         return SECCLASS_NETLINK_FIREWALL_SOCKET;
1002                 case NETLINK_INET_DIAG:
1003                         return SECCLASS_NETLINK_TCPDIAG_SOCKET;
1004                 case NETLINK_NFLOG:
1005                         return SECCLASS_NETLINK_NFLOG_SOCKET;
1006                 case NETLINK_XFRM:
1007                         return SECCLASS_NETLINK_XFRM_SOCKET;
1008                 case NETLINK_SELINUX:
1009                         return SECCLASS_NETLINK_SELINUX_SOCKET;
1010                 case NETLINK_AUDIT:
1011                         return SECCLASS_NETLINK_AUDIT_SOCKET;
1012                 case NETLINK_IP6_FW:
1013                         return SECCLASS_NETLINK_IP6FW_SOCKET;
1014                 case NETLINK_DNRTMSG:
1015                         return SECCLASS_NETLINK_DNRT_SOCKET;
1016                 case NETLINK_KOBJECT_UEVENT:
1017                         return SECCLASS_NETLINK_KOBJECT_UEVENT_SOCKET;
1018                 default:
1019                         return SECCLASS_NETLINK_SOCKET;
1020                 }
1021         case PF_PACKET:
1022                 return SECCLASS_PACKET_SOCKET;
1023         case PF_KEY:
1024                 return SECCLASS_KEY_SOCKET;
1025         case PF_APPLETALK:
1026                 return SECCLASS_APPLETALK_SOCKET;
1027         }
1028
1029         return SECCLASS_SOCKET;
1030 }
1031
1032 #ifdef CONFIG_PROC_FS
1033 static int selinux_proc_get_sid(struct proc_dir_entry *de,
1034                                 u16 tclass,
1035                                 u32 *sid)
1036 {
1037         int buflen, rc;
1038         char *buffer, *path, *end;
1039
1040         buffer = (char*)__get_free_page(GFP_KERNEL);
1041         if (!buffer)
1042                 return -ENOMEM;
1043
1044         buflen = PAGE_SIZE;
1045         end = buffer+buflen;
1046         *--end = '\0';
1047         buflen--;
1048         path = end-1;
1049         *path = '/';
1050         while (de && de != de->parent) {
1051                 buflen -= de->namelen + 1;
1052                 if (buflen < 0)
1053                         break;
1054                 end -= de->namelen;
1055                 memcpy(end, de->name, de->namelen);
1056                 *--end = '/';
1057                 path = end;
1058                 de = de->parent;
1059         }
1060         rc = security_genfs_sid("proc", path, tclass, sid);
1061         free_page((unsigned long)buffer);
1062         return rc;
1063 }
1064 #else
1065 static int selinux_proc_get_sid(struct proc_dir_entry *de,
1066                                 u16 tclass,
1067                                 u32 *sid)
1068 {
1069         return -EINVAL;
1070 }
1071 #endif
1072
1073 /* The inode's security attributes must be initialized before first use. */
1074 static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dentry)
1075 {
1076         struct superblock_security_struct *sbsec = NULL;
1077         struct inode_security_struct *isec = inode->i_security;
1078         u32 sid;
1079         struct dentry *dentry;
1080 #define INITCONTEXTLEN 255
1081         char *context = NULL;
1082         unsigned len = 0;
1083         int rc = 0;
1084
1085         if (isec->initialized)
1086                 goto out;
1087
1088         mutex_lock(&isec->lock);
1089         if (isec->initialized)
1090                 goto out_unlock;
1091
1092         sbsec = inode->i_sb->s_security;
1093         if (!sbsec->initialized) {
1094                 /* Defer initialization until selinux_complete_init,
1095                    after the initial policy is loaded and the security
1096                    server is ready to handle calls. */
1097                 spin_lock(&sbsec->isec_lock);
1098                 if (list_empty(&isec->list))
1099                         list_add(&isec->list, &sbsec->isec_head);
1100                 spin_unlock(&sbsec->isec_lock);
1101                 goto out_unlock;
1102         }
1103
1104         switch (sbsec->behavior) {
1105         case SECURITY_FS_USE_XATTR:
1106                 if (!inode->i_op->getxattr) {
1107                         isec->sid = sbsec->def_sid;
1108                         break;
1109                 }
1110
1111                 /* Need a dentry, since the xattr API requires one.
1112                    Life would be simpler if we could just pass the inode. */
1113                 if (opt_dentry) {
1114                         /* Called from d_instantiate or d_splice_alias. */
1115                         dentry = dget(opt_dentry);
1116                 } else {
1117                         /* Called from selinux_complete_init, try to find a dentry. */
1118                         dentry = d_find_alias(inode);
1119                 }
1120                 if (!dentry) {
1121                         printk(KERN_WARNING "%s:  no dentry for dev=%s "
1122                                "ino=%ld\n", __FUNCTION__, inode->i_sb->s_id,
1123                                inode->i_ino);
1124                         goto out_unlock;
1125                 }
1126
1127                 len = INITCONTEXTLEN;
1128                 context = kmalloc(len, GFP_KERNEL);
1129                 if (!context) {
1130                         rc = -ENOMEM;
1131                         dput(dentry);
1132                         goto out_unlock;
1133                 }
1134                 rc = inode->i_op->getxattr(dentry, XATTR_NAME_SELINUX,
1135                                            context, len);
1136                 if (rc == -ERANGE) {
1137                         /* Need a larger buffer.  Query for the right size. */
1138                         rc = inode->i_op->getxattr(dentry, XATTR_NAME_SELINUX,
1139                                                    NULL, 0);
1140                         if (rc < 0) {
1141                                 dput(dentry);
1142                                 goto out_unlock;
1143                         }
1144                         kfree(context);
1145                         len = rc;
1146                         context = kmalloc(len, GFP_KERNEL);
1147                         if (!context) {
1148                                 rc = -ENOMEM;
1149                                 dput(dentry);
1150                                 goto out_unlock;
1151                         }
1152                         rc = inode->i_op->getxattr(dentry,
1153                                                    XATTR_NAME_SELINUX,
1154                                                    context, len);
1155                 }
1156                 dput(dentry);
1157                 if (rc < 0) {
1158                         if (rc != -ENODATA) {
1159                                 printk(KERN_WARNING "%s:  getxattr returned "
1160                                        "%d for dev=%s ino=%ld\n", __FUNCTION__,
1161                                        -rc, inode->i_sb->s_id, inode->i_ino);
1162                                 kfree(context);
1163                                 goto out_unlock;
1164                         }
1165                         /* Map ENODATA to the default file SID */
1166                         sid = sbsec->def_sid;
1167                         rc = 0;
1168                 } else {
1169                         rc = security_context_to_sid_default(context, rc, &sid,
1170                                                              sbsec->def_sid);
1171                         if (rc) {
1172                                 printk(KERN_WARNING "%s:  context_to_sid(%s) "
1173                                        "returned %d for dev=%s ino=%ld\n",
1174                                        __FUNCTION__, context, -rc,
1175                                        inode->i_sb->s_id, inode->i_ino);
1176                                 kfree(context);
1177                                 /* Leave with the unlabeled SID */
1178                                 rc = 0;
1179                                 break;
1180                         }
1181                 }
1182                 kfree(context);
1183                 isec->sid = sid;
1184                 break;
1185         case SECURITY_FS_USE_TASK:
1186                 isec->sid = isec->task_sid;
1187                 break;
1188         case SECURITY_FS_USE_TRANS:
1189                 /* Default to the fs SID. */
1190                 isec->sid = sbsec->sid;
1191
1192                 /* Try to obtain a transition SID. */
1193                 isec->sclass = inode_mode_to_security_class(inode->i_mode);
1194                 rc = security_transition_sid(isec->task_sid,
1195                                              sbsec->sid,
1196                                              isec->sclass,
1197                                              &sid);
1198                 if (rc)
1199                         goto out_unlock;
1200                 isec->sid = sid;
1201                 break;
1202         case SECURITY_FS_USE_MNTPOINT:
1203                 isec->sid = sbsec->mntpoint_sid;
1204                 break;
1205         default:
1206                 /* Default to the fs superblock SID. */
1207                 isec->sid = sbsec->sid;
1208
1209                 if (sbsec->proc) {
1210                         struct proc_inode *proci = PROC_I(inode);
1211                         if (proci->pde) {
1212                                 isec->sclass = inode_mode_to_security_class(inode->i_mode);
1213                                 rc = selinux_proc_get_sid(proci->pde,
1214                                                           isec->sclass,
1215                                                           &sid);
1216                                 if (rc)
1217                                         goto out_unlock;
1218                                 isec->sid = sid;
1219                         }
1220                 }
1221                 break;
1222         }
1223
1224         isec->initialized = 1;
1225
1226 out_unlock:
1227         mutex_unlock(&isec->lock);
1228 out:
1229         if (isec->sclass == SECCLASS_FILE)
1230                 isec->sclass = inode_mode_to_security_class(inode->i_mode);
1231         return rc;
1232 }
1233
1234 /* Convert a Linux signal to an access vector. */
1235 static inline u32 signal_to_av(int sig)
1236 {
1237         u32 perm = 0;
1238
1239         switch (sig) {
1240         case SIGCHLD:
1241                 /* Commonly granted from child to parent. */
1242                 perm = PROCESS__SIGCHLD;
1243                 break;
1244         case SIGKILL:
1245                 /* Cannot be caught or ignored */
1246                 perm = PROCESS__SIGKILL;
1247                 break;
1248         case SIGSTOP:
1249                 /* Cannot be caught or ignored */
1250                 perm = PROCESS__SIGSTOP;
1251                 break;
1252         default:
1253                 /* All other signals. */
1254                 perm = PROCESS__SIGNAL;
1255                 break;
1256         }
1257
1258         return perm;
1259 }
1260
1261 /* Check permission betweeen a pair of tasks, e.g. signal checks,
1262    fork check, ptrace check, etc. */
1263 static int task_has_perm(struct task_struct *tsk1,
1264                          struct task_struct *tsk2,
1265                          u32 perms)
1266 {
1267         struct task_security_struct *tsec1, *tsec2;
1268
1269         tsec1 = tsk1->security;
1270         tsec2 = tsk2->security;
1271         return avc_has_perm(tsec1->sid, tsec2->sid,
1272                             SECCLASS_PROCESS, perms, NULL);
1273 }
1274
1275 #if CAP_LAST_CAP > 63
1276 #error Fix SELinux to handle capabilities > 63.
1277 #endif
1278
1279 /* Check whether a task is allowed to use a capability. */
1280 static int task_has_capability(struct task_struct *tsk,
1281                                int cap)
1282 {
1283         struct task_security_struct *tsec;
1284         struct avc_audit_data ad;
1285         u16 sclass;
1286         u32 av = CAP_TO_MASK(cap);
1287
1288         tsec = tsk->security;
1289
1290         AVC_AUDIT_DATA_INIT(&ad,CAP);
1291         ad.tsk = tsk;
1292         ad.u.cap = cap;
1293
1294         switch (CAP_TO_INDEX(cap)) {
1295         case 0:
1296                 sclass = SECCLASS_CAPABILITY;
1297                 break;
1298         case 1:
1299                 sclass = SECCLASS_CAPABILITY2;
1300                 break;
1301         default:
1302                 printk(KERN_ERR
1303                        "SELinux:  out of range capability %d\n", cap);
1304                 BUG();
1305         }
1306         return avc_has_perm(tsec->sid, tsec->sid, sclass, av, &ad);
1307 }
1308
1309 /* Check whether a task is allowed to use a system operation. */
1310 static int task_has_system(struct task_struct *tsk,
1311                            u32 perms)
1312 {
1313         struct task_security_struct *tsec;
1314
1315         tsec = tsk->security;
1316
1317         return avc_has_perm(tsec->sid, SECINITSID_KERNEL,
1318                             SECCLASS_SYSTEM, perms, NULL);
1319 }
1320
1321 /* Check whether a task has a particular permission to an inode.
1322    The 'adp' parameter is optional and allows other audit
1323    data to be passed (e.g. the dentry). */
1324 static int inode_has_perm(struct task_struct *tsk,
1325                           struct inode *inode,
1326                           u32 perms,
1327                           struct avc_audit_data *adp)
1328 {
1329         struct task_security_struct *tsec;
1330         struct inode_security_struct *isec;
1331         struct avc_audit_data ad;
1332
1333         if (unlikely (IS_PRIVATE (inode)))
1334                 return 0;
1335
1336         tsec = tsk->security;
1337         isec = inode->i_security;
1338
1339         if (!adp) {
1340                 adp = &ad;
1341                 AVC_AUDIT_DATA_INIT(&ad, FS);
1342                 ad.u.fs.inode = inode;
1343         }
1344
1345         return avc_has_perm(tsec->sid, isec->sid, isec->sclass, perms, adp);
1346 }
1347
1348 /* Same as inode_has_perm, but pass explicit audit data containing
1349    the dentry to help the auditing code to more easily generate the
1350    pathname if needed. */
1351 static inline int dentry_has_perm(struct task_struct *tsk,
1352                                   struct vfsmount *mnt,
1353                                   struct dentry *dentry,
1354                                   u32 av)
1355 {
1356         struct inode *inode = dentry->d_inode;
1357         struct avc_audit_data ad;
1358         AVC_AUDIT_DATA_INIT(&ad,FS);
1359         ad.u.fs.mnt = mnt;
1360         ad.u.fs.dentry = dentry;
1361         return inode_has_perm(tsk, inode, av, &ad);
1362 }
1363
1364 /* Check whether a task can use an open file descriptor to
1365    access an inode in a given way.  Check access to the
1366    descriptor itself, and then use dentry_has_perm to
1367    check a particular permission to the file.
1368    Access to the descriptor is implicitly granted if it
1369    has the same SID as the process.  If av is zero, then
1370    access to the file is not checked, e.g. for cases
1371    where only the descriptor is affected like seek. */
1372 static int file_has_perm(struct task_struct *tsk,
1373                                 struct file *file,
1374                                 u32 av)
1375 {
1376         struct task_security_struct *tsec = tsk->security;
1377         struct file_security_struct *fsec = file->f_security;
1378         struct vfsmount *mnt = file->f_path.mnt;
1379         struct dentry *dentry = file->f_path.dentry;
1380         struct inode *inode = dentry->d_inode;
1381         struct avc_audit_data ad;
1382         int rc;
1383
1384         AVC_AUDIT_DATA_INIT(&ad, FS);
1385         ad.u.fs.mnt = mnt;
1386         ad.u.fs.dentry = dentry;
1387
1388         if (tsec->sid != fsec->sid) {
1389                 rc = avc_has_perm(tsec->sid, fsec->sid,
1390                                   SECCLASS_FD,
1391                                   FD__USE,
1392                                   &ad);
1393                 if (rc)
1394                         return rc;
1395         }
1396
1397         /* av is zero if only checking access to the descriptor. */
1398         if (av)
1399                 return inode_has_perm(tsk, inode, av, &ad);
1400
1401         return 0;
1402 }
1403
1404 /* Check whether a task can create a file. */
1405 static int may_create(struct inode *dir,
1406                       struct dentry *dentry,
1407                       u16 tclass)
1408 {
1409         struct task_security_struct *tsec;
1410         struct inode_security_struct *dsec;
1411         struct superblock_security_struct *sbsec;
1412         u32 newsid;
1413         struct avc_audit_data ad;
1414         int rc;
1415
1416         tsec = current->security;
1417         dsec = dir->i_security;
1418         sbsec = dir->i_sb->s_security;
1419
1420         AVC_AUDIT_DATA_INIT(&ad, FS);
1421         ad.u.fs.dentry = dentry;
1422
1423         rc = avc_has_perm(tsec->sid, dsec->sid, SECCLASS_DIR,
1424                           DIR__ADD_NAME | DIR__SEARCH,
1425                           &ad);
1426         if (rc)
1427                 return rc;
1428
1429         if (tsec->create_sid && sbsec->behavior != SECURITY_FS_USE_MNTPOINT) {
1430                 newsid = tsec->create_sid;
1431         } else {
1432                 rc = security_transition_sid(tsec->sid, dsec->sid, tclass,
1433                                              &newsid);
1434                 if (rc)
1435                         return rc;
1436         }
1437
1438         rc = avc_has_perm(tsec->sid, newsid, tclass, FILE__CREATE, &ad);
1439         if (rc)
1440                 return rc;
1441
1442         return avc_has_perm(newsid, sbsec->sid,
1443                             SECCLASS_FILESYSTEM,
1444                             FILESYSTEM__ASSOCIATE, &ad);
1445 }
1446
1447 /* Check whether a task can create a key. */
1448 static int may_create_key(u32 ksid,
1449                           struct task_struct *ctx)
1450 {
1451         struct task_security_struct *tsec;
1452
1453         tsec = ctx->security;
1454
1455         return avc_has_perm(tsec->sid, ksid, SECCLASS_KEY, KEY__CREATE, NULL);
1456 }
1457
1458 #define MAY_LINK   0
1459 #define MAY_UNLINK 1
1460 #define MAY_RMDIR  2
1461
1462 /* Check whether a task can link, unlink, or rmdir a file/directory. */
1463 static int may_link(struct inode *dir,
1464                     struct dentry *dentry,
1465                     int kind)
1466
1467 {
1468         struct task_security_struct *tsec;
1469         struct inode_security_struct *dsec, *isec;
1470         struct avc_audit_data ad;
1471         u32 av;
1472         int rc;
1473
1474         tsec = current->security;
1475         dsec = dir->i_security;
1476         isec = dentry->d_inode->i_security;
1477
1478         AVC_AUDIT_DATA_INIT(&ad, FS);
1479         ad.u.fs.dentry = dentry;
1480
1481         av = DIR__SEARCH;
1482         av |= (kind ? DIR__REMOVE_NAME : DIR__ADD_NAME);
1483         rc = avc_has_perm(tsec->sid, dsec->sid, SECCLASS_DIR, av, &ad);
1484         if (rc)
1485                 return rc;
1486
1487         switch (kind) {
1488         case MAY_LINK:
1489                 av = FILE__LINK;
1490                 break;
1491         case MAY_UNLINK:
1492                 av = FILE__UNLINK;
1493                 break;
1494         case MAY_RMDIR:
1495                 av = DIR__RMDIR;
1496                 break;
1497         default:
1498                 printk(KERN_WARNING "may_link:  unrecognized kind %d\n", kind);
1499                 return 0;
1500         }
1501
1502         rc = avc_has_perm(tsec->sid, isec->sid, isec->sclass, av, &ad);
1503         return rc;
1504 }
1505
1506 static inline int may_rename(struct inode *old_dir,
1507                              struct dentry *old_dentry,
1508                              struct inode *new_dir,
1509                              struct dentry *new_dentry)
1510 {
1511         struct task_security_struct *tsec;
1512         struct inode_security_struct *old_dsec, *new_dsec, *old_isec, *new_isec;
1513         struct avc_audit_data ad;
1514         u32 av;
1515         int old_is_dir, new_is_dir;
1516         int rc;
1517
1518         tsec = current->security;
1519         old_dsec = old_dir->i_security;
1520         old_isec = old_dentry->d_inode->i_security;
1521         old_is_dir = S_ISDIR(old_dentry->d_inode->i_mode);
1522         new_dsec = new_dir->i_security;
1523
1524         AVC_AUDIT_DATA_INIT(&ad, FS);
1525
1526         ad.u.fs.dentry = old_dentry;
1527         rc = avc_has_perm(tsec->sid, old_dsec->sid, SECCLASS_DIR,
1528                           DIR__REMOVE_NAME | DIR__SEARCH, &ad);
1529         if (rc)
1530                 return rc;
1531         rc = avc_has_perm(tsec->sid, old_isec->sid,
1532                           old_isec->sclass, FILE__RENAME, &ad);
1533         if (rc)
1534                 return rc;
1535         if (old_is_dir && new_dir != old_dir) {
1536                 rc = avc_has_perm(tsec->sid, old_isec->sid,
1537                                   old_isec->sclass, DIR__REPARENT, &ad);
1538                 if (rc)
1539                         return rc;
1540         }
1541
1542         ad.u.fs.dentry = new_dentry;
1543         av = DIR__ADD_NAME | DIR__SEARCH;
1544         if (new_dentry->d_inode)
1545                 av |= DIR__REMOVE_NAME;
1546         rc = avc_has_perm(tsec->sid, new_dsec->sid, SECCLASS_DIR, av, &ad);
1547         if (rc)
1548                 return rc;
1549         if (new_dentry->d_inode) {
1550                 new_isec = new_dentry->d_inode->i_security;
1551                 new_is_dir = S_ISDIR(new_dentry->d_inode->i_mode);
1552                 rc = avc_has_perm(tsec->sid, new_isec->sid,
1553                                   new_isec->sclass,
1554                                   (new_is_dir ? DIR__RMDIR : FILE__UNLINK), &ad);
1555                 if (rc)
1556                         return rc;
1557         }
1558
1559         return 0;
1560 }
1561
1562 /* Check whether a task can perform a filesystem operation. */
1563 static int superblock_has_perm(struct task_struct *tsk,
1564                                struct super_block *sb,
1565                                u32 perms,
1566                                struct avc_audit_data *ad)
1567 {
1568         struct task_security_struct *tsec;
1569         struct superblock_security_struct *sbsec;
1570
1571         tsec = tsk->security;
1572         sbsec = sb->s_security;
1573         return avc_has_perm(tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM,
1574                             perms, ad);
1575 }
1576
1577 /* Convert a Linux mode and permission mask to an access vector. */
1578 static inline u32 file_mask_to_av(int mode, int mask)
1579 {
1580         u32 av = 0;
1581
1582         if ((mode & S_IFMT) != S_IFDIR) {
1583                 if (mask & MAY_EXEC)
1584                         av |= FILE__EXECUTE;
1585                 if (mask & MAY_READ)
1586                         av |= FILE__READ;
1587
1588                 if (mask & MAY_APPEND)
1589                         av |= FILE__APPEND;
1590                 else if (mask & MAY_WRITE)
1591                         av |= FILE__WRITE;
1592
1593         } else {
1594                 if (mask & MAY_EXEC)
1595                         av |= DIR__SEARCH;
1596                 if (mask & MAY_WRITE)
1597                         av |= DIR__WRITE;
1598                 if (mask & MAY_READ)
1599                         av |= DIR__READ;
1600         }
1601
1602         return av;
1603 }
1604
1605 /* Convert a Linux file to an access vector. */
1606 static inline u32 file_to_av(struct file *file)
1607 {
1608         u32 av = 0;
1609
1610         if (file->f_mode & FMODE_READ)
1611                 av |= FILE__READ;
1612         if (file->f_mode & FMODE_WRITE) {
1613                 if (file->f_flags & O_APPEND)
1614                         av |= FILE__APPEND;
1615                 else
1616                         av |= FILE__WRITE;
1617         }
1618
1619         return av;
1620 }
1621
1622 /* Hook functions begin here. */
1623
1624 static int selinux_ptrace(struct task_struct *parent, struct task_struct *child)
1625 {
1626         struct task_security_struct *psec = parent->security;
1627         struct task_security_struct *csec = child->security;
1628         int rc;
1629
1630         rc = secondary_ops->ptrace(parent,child);
1631         if (rc)
1632                 return rc;
1633
1634         rc = task_has_perm(parent, child, PROCESS__PTRACE);
1635         /* Save the SID of the tracing process for later use in apply_creds. */
1636         if (!(child->ptrace & PT_PTRACED) && !rc)
1637                 csec->ptrace_sid = psec->sid;
1638         return rc;
1639 }
1640
1641 static int selinux_capget(struct task_struct *target, kernel_cap_t *effective,
1642                           kernel_cap_t *inheritable, kernel_cap_t *permitted)
1643 {
1644         int error;
1645
1646         error = task_has_perm(current, target, PROCESS__GETCAP);
1647         if (error)
1648                 return error;
1649
1650         return secondary_ops->capget(target, effective, inheritable, permitted);
1651 }
1652
1653 static int selinux_capset_check(struct task_struct *target, kernel_cap_t *effective,
1654                                 kernel_cap_t *inheritable, kernel_cap_t *permitted)
1655 {
1656         int error;
1657
1658         error = secondary_ops->capset_check(target, effective, inheritable, permitted);
1659         if (error)
1660                 return error;
1661
1662         return task_has_perm(current, target, PROCESS__SETCAP);
1663 }
1664
1665 static void selinux_capset_set(struct task_struct *target, kernel_cap_t *effective,
1666                                kernel_cap_t *inheritable, kernel_cap_t *permitted)
1667 {
1668         secondary_ops->capset_set(target, effective, inheritable, permitted);
1669 }
1670
1671 static int selinux_capable(struct task_struct *tsk, int cap)
1672 {
1673         int rc;
1674
1675         rc = secondary_ops->capable(tsk, cap);
1676         if (rc)
1677                 return rc;
1678
1679         return task_has_capability(tsk,cap);
1680 }
1681
1682 static int selinux_sysctl_get_sid(ctl_table *table, u16 tclass, u32 *sid)
1683 {
1684         int buflen, rc;
1685         char *buffer, *path, *end;
1686
1687         rc = -ENOMEM;
1688         buffer = (char*)__get_free_page(GFP_KERNEL);
1689         if (!buffer)
1690                 goto out;
1691
1692         buflen = PAGE_SIZE;
1693         end = buffer+buflen;
1694         *--end = '\0';
1695         buflen--;
1696         path = end-1;
1697         *path = '/';
1698         while (table) {
1699                 const char *name = table->procname;
1700                 size_t namelen = strlen(name);
1701                 buflen -= namelen + 1;
1702                 if (buflen < 0)
1703                         goto out_free;
1704                 end -= namelen;
1705                 memcpy(end, name, namelen);
1706                 *--end = '/';
1707                 path = end;
1708                 table = table->parent;
1709         }
1710         buflen -= 4;
1711         if (buflen < 0)
1712                 goto out_free;
1713         end -= 4;
1714         memcpy(end, "/sys", 4);
1715         path = end;
1716         rc = security_genfs_sid("proc", path, tclass, sid);
1717 out_free:
1718         free_page((unsigned long)buffer);
1719 out:
1720         return rc;
1721 }
1722
1723 static int selinux_sysctl(ctl_table *table, int op)
1724 {
1725         int error = 0;
1726         u32 av;
1727         struct task_security_struct *tsec;
1728         u32 tsid;
1729         int rc;
1730
1731         rc = secondary_ops->sysctl(table, op);
1732         if (rc)
1733                 return rc;
1734
1735         tsec = current->security;
1736
1737         rc = selinux_sysctl_get_sid(table, (op == 0001) ?
1738                                     SECCLASS_DIR : SECCLASS_FILE, &tsid);
1739         if (rc) {
1740                 /* Default to the well-defined sysctl SID. */
1741                 tsid = SECINITSID_SYSCTL;
1742         }
1743
1744         /* The op values are "defined" in sysctl.c, thereby creating
1745          * a bad coupling between this module and sysctl.c */
1746         if(op == 001) {
1747                 error = avc_has_perm(tsec->sid, tsid,
1748                                      SECCLASS_DIR, DIR__SEARCH, NULL);
1749         } else {
1750                 av = 0;
1751                 if (op & 004)
1752                         av |= FILE__READ;
1753                 if (op & 002)
1754                         av |= FILE__WRITE;
1755                 if (av)
1756                         error = avc_has_perm(tsec->sid, tsid,
1757                                              SECCLASS_FILE, av, NULL);
1758         }
1759
1760         return error;
1761 }
1762
1763 static int selinux_quotactl(int cmds, int type, int id, struct super_block *sb)
1764 {
1765         int rc = 0;
1766
1767         if (!sb)
1768                 return 0;
1769
1770         switch (cmds) {
1771                 case Q_SYNC:
1772                 case Q_QUOTAON:
1773                 case Q_QUOTAOFF:
1774                 case Q_SETINFO:
1775                 case Q_SETQUOTA:
1776                         rc = superblock_has_perm(current,
1777                                                  sb,
1778                                                  FILESYSTEM__QUOTAMOD, NULL);
1779                         break;
1780                 case Q_GETFMT:
1781                 case Q_GETINFO:
1782                 case Q_GETQUOTA:
1783                         rc = superblock_has_perm(current,
1784                                                  sb,
1785                                                  FILESYSTEM__QUOTAGET, NULL);
1786                         break;
1787                 default:
1788                         rc = 0;  /* let the kernel handle invalid cmds */
1789                         break;
1790         }
1791         return rc;
1792 }
1793
1794 static int selinux_quota_on(struct dentry *dentry)
1795 {
1796         return dentry_has_perm(current, NULL, dentry, FILE__QUOTAON);
1797 }
1798
1799 static int selinux_syslog(int type)
1800 {
1801         int rc;
1802
1803         rc = secondary_ops->syslog(type);
1804         if (rc)
1805                 return rc;
1806
1807         switch (type) {
1808                 case 3:         /* Read last kernel messages */
1809                 case 10:        /* Return size of the log buffer */
1810                         rc = task_has_system(current, SYSTEM__SYSLOG_READ);
1811                         break;
1812                 case 6:         /* Disable logging to console */
1813                 case 7:         /* Enable logging to console */
1814                 case 8:         /* Set level of messages printed to console */
1815                         rc = task_has_system(current, SYSTEM__SYSLOG_CONSOLE);
1816                         break;
1817                 case 0:         /* Close log */
1818                 case 1:         /* Open log */
1819                 case 2:         /* Read from log */
1820                 case 4:         /* Read/clear last kernel messages */
1821                 case 5:         /* Clear ring buffer */
1822                 default:
1823                         rc = task_has_system(current, SYSTEM__SYSLOG_MOD);
1824                         break;
1825         }
1826         return rc;
1827 }
1828
1829 /*
1830  * Check that a process has enough memory to allocate a new virtual
1831  * mapping. 0 means there is enough memory for the allocation to
1832  * succeed and -ENOMEM implies there is not.
1833  *
1834  * Note that secondary_ops->capable and task_has_perm_noaudit return 0
1835  * if the capability is granted, but __vm_enough_memory requires 1 if
1836  * the capability is granted.
1837  *
1838  * Do not audit the selinux permission check, as this is applied to all
1839  * processes that allocate mappings.
1840  */
1841 static int selinux_vm_enough_memory(struct mm_struct *mm, long pages)
1842 {
1843         int rc, cap_sys_admin = 0;
1844         struct task_security_struct *tsec = current->security;
1845
1846         rc = secondary_ops->capable(current, CAP_SYS_ADMIN);
1847         if (rc == 0)
1848                 rc = avc_has_perm_noaudit(tsec->sid, tsec->sid,
1849                                           SECCLASS_CAPABILITY,
1850                                           CAP_TO_MASK(CAP_SYS_ADMIN),
1851                                           0,
1852                                           NULL);
1853
1854         if (rc == 0)
1855                 cap_sys_admin = 1;
1856
1857         return __vm_enough_memory(mm, pages, cap_sys_admin);
1858 }
1859
1860 /* binprm security operations */
1861
1862 static int selinux_bprm_alloc_security(struct linux_binprm *bprm)
1863 {
1864         struct bprm_security_struct *bsec;
1865
1866         bsec = kzalloc(sizeof(struct bprm_security_struct), GFP_KERNEL);
1867         if (!bsec)
1868                 return -ENOMEM;
1869
1870         bsec->bprm = bprm;
1871         bsec->sid = SECINITSID_UNLABELED;
1872         bsec->set = 0;
1873
1874         bprm->security = bsec;
1875         return 0;
1876 }
1877
1878 static int selinux_bprm_set_security(struct linux_binprm *bprm)
1879 {
1880         struct task_security_struct *tsec;
1881         struct inode *inode = bprm->file->f_path.dentry->d_inode;
1882         struct inode_security_struct *isec;
1883         struct bprm_security_struct *bsec;
1884         u32 newsid;
1885         struct avc_audit_data ad;
1886         int rc;
1887
1888         rc = secondary_ops->bprm_set_security(bprm);
1889         if (rc)
1890                 return rc;
1891
1892         bsec = bprm->security;
1893
1894         if (bsec->set)
1895                 return 0;
1896
1897         tsec = current->security;
1898         isec = inode->i_security;
1899
1900         /* Default to the current task SID. */
1901         bsec->sid = tsec->sid;
1902
1903         /* Reset fs, key, and sock SIDs on execve. */
1904         tsec->create_sid = 0;
1905         tsec->keycreate_sid = 0;
1906         tsec->sockcreate_sid = 0;
1907
1908         if (tsec->exec_sid) {
1909                 newsid = tsec->exec_sid;
1910                 /* Reset exec SID on execve. */
1911                 tsec->exec_sid = 0;
1912         } else {
1913                 /* Check for a default transition on this program. */
1914                 rc = security_transition_sid(tsec->sid, isec->sid,
1915                                              SECCLASS_PROCESS, &newsid);
1916                 if (rc)
1917                         return rc;
1918         }
1919
1920         AVC_AUDIT_DATA_INIT(&ad, FS);
1921         ad.u.fs.mnt = bprm->file->f_path.mnt;
1922         ad.u.fs.dentry = bprm->file->f_path.dentry;
1923
1924         if (bprm->file->f_path.mnt->mnt_flags & MNT_NOSUID)
1925                 newsid = tsec->sid;
1926
1927         if (tsec->sid == newsid) {
1928                 rc = avc_has_perm(tsec->sid, isec->sid,
1929                                   SECCLASS_FILE, FILE__EXECUTE_NO_TRANS, &ad);
1930                 if (rc)
1931                         return rc;
1932         } else {
1933                 /* Check permissions for the transition. */
1934                 rc = avc_has_perm(tsec->sid, newsid,
1935                                   SECCLASS_PROCESS, PROCESS__TRANSITION, &ad);
1936                 if (rc)
1937                         return rc;
1938
1939                 rc = avc_has_perm(newsid, isec->sid,
1940                                   SECCLASS_FILE, FILE__ENTRYPOINT, &ad);
1941                 if (rc)
1942                         return rc;
1943
1944                 /* Clear any possibly unsafe personality bits on exec: */
1945                 current->personality &= ~PER_CLEAR_ON_SETID;
1946
1947                 /* Set the security field to the new SID. */
1948                 bsec->sid = newsid;
1949         }
1950
1951         bsec->set = 1;
1952         return 0;
1953 }
1954
1955 static int selinux_bprm_check_security (struct linux_binprm *bprm)
1956 {
1957         return secondary_ops->bprm_check_security(bprm);
1958 }
1959
1960
1961 static int selinux_bprm_secureexec (struct linux_binprm *bprm)
1962 {
1963         struct task_security_struct *tsec = current->security;
1964         int atsecure = 0;
1965
1966         if (tsec->osid != tsec->sid) {
1967                 /* Enable secure mode for SIDs transitions unless
1968                    the noatsecure permission is granted between
1969                    the two SIDs, i.e. ahp returns 0. */
1970                 atsecure = avc_has_perm(tsec->osid, tsec->sid,
1971                                          SECCLASS_PROCESS,
1972                                          PROCESS__NOATSECURE, NULL);
1973         }
1974
1975         return (atsecure || secondary_ops->bprm_secureexec(bprm));
1976 }
1977
1978 static void selinux_bprm_free_security(struct linux_binprm *bprm)
1979 {
1980         kfree(bprm->security);
1981         bprm->security = NULL;
1982 }
1983
1984 extern struct vfsmount *selinuxfs_mount;
1985 extern struct dentry *selinux_null;
1986
1987 /* Derived from fs/exec.c:flush_old_files. */
1988 static inline void flush_unauthorized_files(struct files_struct * files)
1989 {
1990         struct avc_audit_data ad;
1991         struct file *file, *devnull = NULL;
1992         struct tty_struct *tty;
1993         struct fdtable *fdt;
1994         long j = -1;
1995         int drop_tty = 0;
1996
1997         mutex_lock(&tty_mutex);
1998         tty = get_current_tty();
1999         if (tty) {
2000                 file_list_lock();
2001                 file = list_entry(tty->tty_files.next, typeof(*file), f_u.fu_list);
2002                 if (file) {
2003                         /* Revalidate access to controlling tty.
2004                            Use inode_has_perm on the tty inode directly rather
2005                            than using file_has_perm, as this particular open
2006                            file may belong to another process and we are only
2007                            interested in the inode-based check here. */
2008                         struct inode *inode = file->f_path.dentry->d_inode;
2009                         if (inode_has_perm(current, inode,
2010                                            FILE__READ | FILE__WRITE, NULL)) {
2011                                 drop_tty = 1;
2012                         }
2013                 }
2014                 file_list_unlock();
2015         }
2016         mutex_unlock(&tty_mutex);
2017         /* Reset controlling tty. */
2018         if (drop_tty)
2019                 no_tty();
2020
2021         /* Revalidate access to inherited open files. */
2022
2023         AVC_AUDIT_DATA_INIT(&ad,FS);
2024
2025         spin_lock(&files->file_lock);
2026         for (;;) {
2027                 unsigned long set, i;
2028                 int fd;
2029
2030                 j++;
2031                 i = j * __NFDBITS;
2032                 fdt = files_fdtable(files);
2033                 if (i >= fdt->max_fds)
2034                         break;
2035                 set = fdt->open_fds->fds_bits[j];
2036                 if (!set)
2037                         continue;
2038                 spin_unlock(&files->file_lock);
2039                 for ( ; set ; i++,set >>= 1) {
2040                         if (set & 1) {
2041                                 file = fget(i);
2042                                 if (!file)
2043                                         continue;
2044                                 if (file_has_perm(current,
2045                                                   file,
2046                                                   file_to_av(file))) {
2047                                         sys_close(i);
2048                                         fd = get_unused_fd();
2049                                         if (fd != i) {
2050                                                 if (fd >= 0)
2051                                                         put_unused_fd(fd);
2052                                                 fput(file);
2053                                                 continue;
2054                                         }
2055                                         if (devnull) {
2056                                                 get_file(devnull);
2057                                         } else {
2058                                                 devnull = dentry_open(dget(selinux_null), mntget(selinuxfs_mount), O_RDWR);
2059                                                 if (IS_ERR(devnull)) {
2060                                                         devnull = NULL;
2061                                                         put_unused_fd(fd);
2062                                                         fput(file);
2063                                                         continue;
2064                                                 }
2065                                         }
2066                                         fd_install(fd, devnull);
2067                                 }
2068                                 fput(file);
2069                         }
2070                 }
2071                 spin_lock(&files->file_lock);
2072
2073         }
2074         spin_unlock(&files->file_lock);
2075 }
2076
2077 static void selinux_bprm_apply_creds(struct linux_binprm *bprm, int unsafe)
2078 {
2079         struct task_security_struct *tsec;
2080         struct bprm_security_struct *bsec;
2081         u32 sid;
2082         int rc;
2083
2084         secondary_ops->bprm_apply_creds(bprm, unsafe);
2085
2086         tsec = current->security;
2087
2088         bsec = bprm->security;
2089         sid = bsec->sid;
2090
2091         tsec->osid = tsec->sid;
2092         bsec->unsafe = 0;
2093         if (tsec->sid != sid) {
2094                 /* Check for shared state.  If not ok, leave SID
2095                    unchanged and kill. */
2096                 if (unsafe & LSM_UNSAFE_SHARE) {
2097                         rc = avc_has_perm(tsec->sid, sid, SECCLASS_PROCESS,
2098                                         PROCESS__SHARE, NULL);
2099                         if (rc) {
2100                                 bsec->unsafe = 1;
2101                                 return;
2102                         }
2103                 }
2104
2105                 /* Check for ptracing, and update the task SID if ok.
2106                    Otherwise, leave SID unchanged and kill. */
2107                 if (unsafe & (LSM_UNSAFE_PTRACE | LSM_UNSAFE_PTRACE_CAP)) {
2108                         rc = avc_has_perm(tsec->ptrace_sid, sid,
2109                                           SECCLASS_PROCESS, PROCESS__PTRACE,
2110                                           NULL);
2111                         if (rc) {
2112                                 bsec->unsafe = 1;
2113                                 return;
2114                         }
2115                 }
2116                 tsec->sid = sid;
2117         }
2118 }
2119
2120 /*
2121  * called after apply_creds without the task lock held
2122  */
2123 static void selinux_bprm_post_apply_creds(struct linux_binprm *bprm)
2124 {
2125         struct task_security_struct *tsec;
2126         struct rlimit *rlim, *initrlim;
2127         struct itimerval itimer;
2128         struct bprm_security_struct *bsec;
2129         int rc, i;
2130
2131         tsec = current->security;
2132         bsec = bprm->security;
2133
2134         if (bsec->unsafe) {
2135                 force_sig_specific(SIGKILL, current);
2136                 return;
2137         }
2138         if (tsec->osid == tsec->sid)
2139                 return;
2140
2141         /* Close files for which the new task SID is not authorized. */
2142         flush_unauthorized_files(current->files);
2143
2144         /* Check whether the new SID can inherit signal state
2145            from the old SID.  If not, clear itimers to avoid
2146            subsequent signal generation and flush and unblock
2147            signals. This must occur _after_ the task SID has
2148           been updated so that any kill done after the flush
2149           will be checked against the new SID. */
2150         rc = avc_has_perm(tsec->osid, tsec->sid, SECCLASS_PROCESS,
2151                           PROCESS__SIGINH, NULL);
2152         if (rc) {
2153                 memset(&itimer, 0, sizeof itimer);
2154                 for (i = 0; i < 3; i++)
2155                         do_setitimer(i, &itimer, NULL);
2156                 flush_signals(current);
2157                 spin_lock_irq(&current->sighand->siglock);
2158                 flush_signal_handlers(current, 1);
2159                 sigemptyset(&current->blocked);
2160                 recalc_sigpending();
2161                 spin_unlock_irq(&current->sighand->siglock);
2162         }
2163
2164         /* Always clear parent death signal on SID transitions. */
2165         current->pdeath_signal = 0;
2166
2167         /* Check whether the new SID can inherit resource limits
2168            from the old SID.  If not, reset all soft limits to
2169            the lower of the current task's hard limit and the init
2170            task's soft limit.  Note that the setting of hard limits
2171            (even to lower them) can be controlled by the setrlimit
2172            check. The inclusion of the init task's soft limit into
2173            the computation is to avoid resetting soft limits higher
2174            than the default soft limit for cases where the default
2175            is lower than the hard limit, e.g. RLIMIT_CORE or
2176            RLIMIT_STACK.*/
2177         rc = avc_has_perm(tsec->osid, tsec->sid, SECCLASS_PROCESS,
2178                           PROCESS__RLIMITINH, NULL);
2179         if (rc) {
2180                 for (i = 0; i < RLIM_NLIMITS; i++) {
2181                         rlim = current->signal->rlim + i;
2182                         initrlim = init_task.signal->rlim+i;
2183                         rlim->rlim_cur = min(rlim->rlim_max,initrlim->rlim_cur);
2184                 }
2185                 if (current->signal->rlim[RLIMIT_CPU].rlim_cur != RLIM_INFINITY) {
2186                         /*
2187                          * This will cause RLIMIT_CPU calculations
2188                          * to be refigured.
2189                          */
2190                         current->it_prof_expires = jiffies_to_cputime(1);
2191                 }
2192         }
2193
2194         /* Wake up the parent if it is waiting so that it can
2195            recheck wait permission to the new task SID. */
2196         wake_up_interruptible(&current->parent->signal->wait_chldexit);
2197 }
2198
2199 /* superblock security operations */
2200
2201 static int selinux_sb_alloc_security(struct super_block *sb)
2202 {
2203         return superblock_alloc_security(sb);
2204 }
2205
2206 static void selinux_sb_free_security(struct super_block *sb)
2207 {
2208         superblock_free_security(sb);
2209 }
2210
2211 static inline int match_prefix(char *prefix, int plen, char *option, int olen)
2212 {
2213         if (plen > olen)
2214                 return 0;
2215
2216         return !memcmp(prefix, option, plen);
2217 }
2218
2219 static inline int selinux_option(char *option, int len)
2220 {
2221         return (match_prefix("context=", sizeof("context=")-1, option, len) ||
2222                 match_prefix("fscontext=", sizeof("fscontext=")-1, option, len) ||
2223                 match_prefix("defcontext=", sizeof("defcontext=")-1, option, len) ||
2224                 match_prefix("rootcontext=", sizeof("rootcontext=")-1, option, len));
2225 }
2226
2227 static inline void take_option(char **to, char *from, int *first, int len)
2228 {
2229         if (!*first) {
2230                 **to = ',';
2231                 *to += 1;
2232         } else
2233                 *first = 0;
2234         memcpy(*to, from, len);
2235         *to += len;
2236 }
2237
2238 static inline void take_selinux_option(char **to, char *from, int *first,
2239                                        int len)
2240 {
2241         int current_size = 0;
2242
2243         if (!*first) {
2244                 **to = '|';
2245                 *to += 1;
2246         }
2247         else
2248                 *first = 0;
2249
2250         while (current_size < len) {
2251                 if (*from != '"') {
2252                         **to = *from;
2253                         *to += 1;
2254                 }
2255                 from += 1;
2256                 current_size += 1;
2257         }
2258 }
2259
2260 static int selinux_sb_copy_data(struct file_system_type *type, void *orig, void *copy)
2261 {
2262         int fnosec, fsec, rc = 0;
2263         char *in_save, *in_curr, *in_end;
2264         char *sec_curr, *nosec_save, *nosec;
2265         int open_quote = 0;
2266
2267         in_curr = orig;
2268         sec_curr = copy;
2269
2270         /* Binary mount data: just copy */
2271         if (type->fs_flags & FS_BINARY_MOUNTDATA) {
2272                 copy_page(sec_curr, in_curr);
2273                 goto out;
2274         }
2275
2276         nosec = (char *)get_zeroed_page(GFP_KERNEL);
2277         if (!nosec) {
2278                 rc = -ENOMEM;
2279                 goto out;
2280         }
2281
2282         nosec_save = nosec;
2283         fnosec = fsec = 1;
2284         in_save = in_end = orig;
2285
2286         do {
2287                 if (*in_end == '"')
2288                         open_quote = !open_quote;
2289                 if ((*in_end == ',' && open_quote == 0) ||
2290                                 *in_end == '\0') {
2291                         int len = in_end - in_curr;
2292
2293                         if (selinux_option(in_curr, len))
2294                                 take_selinux_option(&sec_curr, in_curr, &fsec, len);
2295                         else
2296                                 take_option(&nosec, in_curr, &fnosec, len);
2297
2298                         in_curr = in_end + 1;
2299                 }
2300         } while (*in_end++);
2301
2302         strcpy(in_save, nosec_save);
2303         free_page((unsigned long)nosec_save);
2304 out:
2305         return rc;
2306 }
2307
2308 static int selinux_sb_kern_mount(struct super_block *sb, void *data)
2309 {
2310         struct avc_audit_data ad;
2311         int rc;
2312
2313         rc = superblock_doinit(sb, data);
2314         if (rc)
2315                 return rc;
2316
2317         AVC_AUDIT_DATA_INIT(&ad,FS);
2318         ad.u.fs.dentry = sb->s_root;
2319         return superblock_has_perm(current, sb, FILESYSTEM__MOUNT, &ad);
2320 }
2321
2322 static int selinux_sb_statfs(struct dentry *dentry)
2323 {
2324         struct avc_audit_data ad;
2325
2326         AVC_AUDIT_DATA_INIT(&ad,FS);
2327         ad.u.fs.dentry = dentry->d_sb->s_root;
2328         return superblock_has_perm(current, dentry->d_sb, FILESYSTEM__GETATTR, &ad);
2329 }
2330
2331 static int selinux_mount(char * dev_name,
2332                          struct nameidata *nd,
2333                          char * type,
2334                          unsigned long flags,
2335                          void * data)
2336 {
2337         int rc;
2338
2339         rc = secondary_ops->sb_mount(dev_name, nd, type, flags, data);
2340         if (rc)
2341                 return rc;
2342
2343         if (flags & MS_REMOUNT)
2344                 return superblock_has_perm(current, nd->mnt->mnt_sb,
2345                                            FILESYSTEM__REMOUNT, NULL);
2346         else
2347                 return dentry_has_perm(current, nd->mnt, nd->dentry,
2348                                        FILE__MOUNTON);
2349 }
2350
2351 static int selinux_umount(struct vfsmount *mnt, int flags)
2352 {
2353         int rc;
2354
2355         rc = secondary_ops->sb_umount(mnt, flags);
2356         if (rc)
2357                 return rc;
2358
2359         return superblock_has_perm(current,mnt->mnt_sb,
2360                                    FILESYSTEM__UNMOUNT,NULL);
2361 }
2362
2363 /* inode security operations */
2364
2365 static int selinux_inode_alloc_security(struct inode *inode)
2366 {
2367         return inode_alloc_security(inode);
2368 }
2369
2370 static void selinux_inode_free_security(struct inode *inode)
2371 {
2372         inode_free_security(inode);
2373 }
2374
2375 static int selinux_inode_init_security(struct inode *inode, struct inode *dir,
2376                                        char **name, void **value,
2377                                        size_t *len)
2378 {
2379         struct task_security_struct *tsec;
2380         struct inode_security_struct *dsec;
2381         struct superblock_security_struct *sbsec;
2382         u32 newsid, clen;
2383         int rc;
2384         char *namep = NULL, *context;
2385
2386         tsec = current->security;
2387         dsec = dir->i_security;
2388         sbsec = dir->i_sb->s_security;
2389
2390         if (tsec->create_sid && sbsec->behavior != SECURITY_FS_USE_MNTPOINT) {
2391                 newsid = tsec->create_sid;
2392         } else {
2393                 rc = security_transition_sid(tsec->sid, dsec->sid,
2394                                              inode_mode_to_security_class(inode->i_mode),
2395                                              &newsid);
2396                 if (rc) {
2397                         printk(KERN_WARNING "%s:  "
2398                                "security_transition_sid failed, rc=%d (dev=%s "
2399                                "ino=%ld)\n",
2400                                __FUNCTION__,
2401                                -rc, inode->i_sb->s_id, inode->i_ino);
2402                         return rc;
2403                 }
2404         }
2405
2406         /* Possibly defer initialization to selinux_complete_init. */
2407         if (sbsec->initialized) {
2408                 struct inode_security_struct *isec = inode->i_security;
2409                 isec->sclass = inode_mode_to_security_class(inode->i_mode);
2410                 isec->sid = newsid;
2411                 isec->initialized = 1;
2412         }
2413
2414         if (!ss_initialized || sbsec->behavior == SECURITY_FS_USE_MNTPOINT)
2415                 return -EOPNOTSUPP;
2416
2417         if (name) {
2418                 namep = kstrdup(XATTR_SELINUX_SUFFIX, GFP_KERNEL);
2419                 if (!namep)
2420                         return -ENOMEM;
2421                 *name = namep;
2422         }
2423
2424         if (value && len) {
2425                 rc = security_sid_to_context(newsid, &context, &clen);
2426                 if (rc) {
2427                         kfree(namep);
2428                         return rc;
2429                 }
2430                 *value = context;
2431                 *len = clen;
2432         }
2433
2434         return 0;
2435 }
2436
2437 static int selinux_inode_create(struct inode *dir, struct dentry *dentry, int mask)
2438 {
2439         return may_create(dir, dentry, SECCLASS_FILE);
2440 }
2441
2442 static int selinux_inode_link(struct dentry *old_dentry, struct inode *dir, struct dentry *new_dentry)
2443 {
2444         int rc;
2445
2446         rc = secondary_ops->inode_link(old_dentry,dir,new_dentry);
2447         if (rc)
2448                 return rc;
2449         return may_link(dir, old_dentry, MAY_LINK);
2450 }
2451
2452 static int selinux_inode_unlink(struct inode *dir, struct dentry *dentry)
2453 {
2454         int rc;
2455
2456         rc = secondary_ops->inode_unlink(dir, dentry);
2457         if (rc)
2458                 return rc;
2459         return may_link(dir, dentry, MAY_UNLINK);
2460 }
2461
2462 static int selinux_inode_symlink(struct inode *dir, struct dentry *dentry, const char *name)
2463 {
2464         return may_create(dir, dentry, SECCLASS_LNK_FILE);
2465 }
2466
2467 static int selinux_inode_mkdir(struct inode *dir, struct dentry *dentry, int mask)
2468 {
2469         return may_create(dir, dentry, SECCLASS_DIR);
2470 }
2471
2472 static int selinux_inode_rmdir(struct inode *dir, struct dentry *dentry)
2473 {
2474         return may_link(dir, dentry, MAY_RMDIR);
2475 }
2476
2477 static int selinux_inode_mknod(struct inode *dir, struct dentry *dentry, int mode, dev_t dev)
2478 {
2479         int rc;
2480
2481         rc = secondary_ops->inode_mknod(dir, dentry, mode, dev);
2482         if (rc)
2483                 return rc;
2484
2485         return may_create(dir, dentry, inode_mode_to_security_class(mode));
2486 }
2487
2488 static int selinux_inode_rename(struct inode *old_inode, struct dentry *old_dentry,
2489                                 struct inode *new_inode, struct dentry *new_dentry)
2490 {
2491         return may_rename(old_inode, old_dentry, new_inode, new_dentry);
2492 }
2493
2494 static int selinux_inode_readlink(struct dentry *dentry)
2495 {
2496         return dentry_has_perm(current, NULL, dentry, FILE__READ);
2497 }
2498
2499 static int selinux_inode_follow_link(struct dentry *dentry, struct nameidata *nameidata)
2500 {
2501         int rc;
2502
2503         rc = secondary_ops->inode_follow_link(dentry,nameidata);
2504         if (rc)
2505                 return rc;
2506         return dentry_has_perm(current, NULL, dentry, FILE__READ);
2507 }
2508
2509 static int selinux_inode_permission(struct inode *inode, int mask,
2510                                     struct nameidata *nd)
2511 {
2512         int rc;
2513
2514         rc = secondary_ops->inode_permission(inode, mask, nd);
2515         if (rc)
2516                 return rc;
2517
2518         if (!mask) {
2519                 /* No permission to check.  Existence test. */
2520                 return 0;
2521         }
2522
2523         return inode_has_perm(current, inode,
2524                                file_mask_to_av(inode->i_mode, mask), NULL);
2525 }
2526
2527 static int selinux_inode_setattr(struct dentry *dentry, struct iattr *iattr)
2528 {
2529         int rc;
2530
2531         rc = secondary_ops->inode_setattr(dentry, iattr);
2532         if (rc)
2533                 return rc;
2534
2535         if (iattr->ia_valid & ATTR_FORCE)
2536                 return 0;
2537
2538         if (iattr->ia_valid & (ATTR_MODE | ATTR_UID | ATTR_GID |
2539                                ATTR_ATIME_SET | ATTR_MTIME_SET))
2540                 return dentry_has_perm(current, NULL, dentry, FILE__SETATTR);
2541
2542         return dentry_has_perm(current, NULL, dentry, FILE__WRITE);
2543 }
2544
2545 static int selinux_inode_getattr(struct vfsmount *mnt, struct dentry *dentry)
2546 {
2547         return dentry_has_perm(current, mnt, dentry, FILE__GETATTR);
2548 }
2549
2550 static int selinux_inode_setotherxattr(struct dentry *dentry, char *name)
2551 {
2552         if (!strncmp(name, XATTR_SECURITY_PREFIX,
2553                      sizeof XATTR_SECURITY_PREFIX - 1)) {
2554                 if (!strcmp(name, XATTR_NAME_CAPS)) {
2555                         if (!capable(CAP_SETFCAP))
2556                                 return -EPERM;
2557                 } else if (!capable(CAP_SYS_ADMIN)) {
2558                         /* A different attribute in the security namespace.
2559                            Restrict to administrator. */
2560                         return -EPERM;
2561                 }
2562         }
2563
2564         /* Not an attribute we recognize, so just check the
2565            ordinary setattr permission. */
2566         return dentry_has_perm(current, NULL, dentry, FILE__SETATTR);
2567 }
2568
2569 static int selinux_inode_setxattr(struct dentry *dentry, char *name, void *value, size_t size, int flags)
2570 {
2571         struct task_security_struct *tsec = current->security;
2572         struct inode *inode = dentry->d_inode;
2573         struct inode_security_struct *isec = inode->i_security;
2574         struct superblock_security_struct *sbsec;
2575         struct avc_audit_data ad;
2576         u32 newsid;
2577         int rc = 0;
2578
2579         if (strcmp(name, XATTR_NAME_SELINUX))
2580                 return selinux_inode_setotherxattr(dentry, name);
2581
2582         sbsec = inode->i_sb->s_security;
2583         if (sbsec->behavior == SECURITY_FS_USE_MNTPOINT)
2584                 return -EOPNOTSUPP;
2585
2586         if (!is_owner_or_cap(inode))
2587                 return -EPERM;
2588
2589         AVC_AUDIT_DATA_INIT(&ad,FS);
2590         ad.u.fs.dentry = dentry;
2591
2592         rc = avc_has_perm(tsec->sid, isec->sid, isec->sclass,
2593                           FILE__RELABELFROM, &ad);
2594         if (rc)
2595                 return rc;
2596
2597         rc = security_context_to_sid(value, size, &newsid);
2598         if (rc)
2599                 return rc;
2600
2601         rc = avc_has_perm(tsec->sid, newsid, isec->sclass,
2602                           FILE__RELABELTO, &ad);
2603         if (rc)
2604                 return rc;
2605
2606         rc = security_validate_transition(isec->sid, newsid, tsec->sid,
2607                                           isec->sclass);
2608         if (rc)
2609                 return rc;
2610
2611         return avc_has_perm(newsid,
2612                             sbsec->sid,
2613                             SECCLASS_FILESYSTEM,
2614                             FILESYSTEM__ASSOCIATE,
2615                             &ad);
2616 }
2617
2618 static void selinux_inode_post_setxattr(struct dentry *dentry, char *name,
2619                                         void *value, size_t size, int flags)
2620 {
2621         struct inode *inode = dentry->d_inode;
2622         struct inode_security_struct *isec = inode->i_security;
2623         u32 newsid;
2624         int rc;
2625
2626         if (strcmp(name, XATTR_NAME_SELINUX)) {
2627                 /* Not an attribute we recognize, so nothing to do. */
2628                 return;
2629         }
2630
2631         rc = security_context_to_sid(value, size, &newsid);
2632         if (rc) {
2633                 printk(KERN_WARNING "%s:  unable to obtain SID for context "
2634                        "%s, rc=%d\n", __FUNCTION__, (char*)value, -rc);
2635                 return;
2636         }
2637
2638         isec->sid = newsid;
2639         return;
2640 }
2641
2642 static int selinux_inode_getxattr (struct dentry *dentry, char *name)
2643 {
2644         return dentry_has_perm(current, NULL, dentry, FILE__GETATTR);
2645 }
2646
2647 static int selinux_inode_listxattr (struct dentry *dentry)
2648 {
2649         return dentry_has_perm(current, NULL, dentry, FILE__GETATTR);
2650 }
2651
2652 static int selinux_inode_removexattr (struct dentry *dentry, char *name)
2653 {
2654         if (strcmp(name, XATTR_NAME_SELINUX))
2655                 return selinux_inode_setotherxattr(dentry, name);
2656
2657         /* No one is allowed to remove a SELinux security label.
2658            You can change the label, but all data must be labeled. */
2659         return -EACCES;
2660 }
2661
2662 /*
2663  * Copy the in-core inode security context value to the user.  If the
2664  * getxattr() prior to this succeeded, check to see if we need to
2665  * canonicalize the value to be finally returned to the user.
2666  *
2667  * Permission check is handled by selinux_inode_getxattr hook.
2668  */
2669 static int selinux_inode_getsecurity(const struct inode *inode, const char *name, void **buffer, bool alloc)
2670 {
2671         u32 size;
2672         int error;
2673         char *context = NULL;
2674         struct inode_security_struct *isec = inode->i_security;
2675
2676         if (strcmp(name, XATTR_SELINUX_SUFFIX))
2677                 return -EOPNOTSUPP;
2678
2679         error = security_sid_to_context(isec->sid, &context, &size);
2680         if (error)
2681                 return error;
2682         error = size;
2683         if (alloc) {
2684                 *buffer = context;
2685                 goto out_nofree;
2686         }
2687         kfree(context);
2688 out_nofree:
2689         return error;
2690 }
2691
2692 static int selinux_inode_setsecurity(struct inode *inode, const char *name,
2693                                      const void *value, size_t size, int flags)
2694 {
2695         struct inode_security_struct *isec = inode->i_security;
2696         u32 newsid;
2697         int rc;
2698
2699         if (strcmp(name, XATTR_SELINUX_SUFFIX))
2700                 return -EOPNOTSUPP;
2701
2702         if (!value || !size)
2703                 return -EACCES;
2704
2705         rc = security_context_to_sid((void*)value, size, &newsid);
2706         if (rc)
2707                 return rc;
2708
2709         isec->sid = newsid;
2710         return 0;
2711 }
2712
2713 static int selinux_inode_listsecurity(struct inode *inode, char *buffer, size_t buffer_size)
2714 {
2715         const int len = sizeof(XATTR_NAME_SELINUX);
2716         if (buffer && len <= buffer_size)
2717                 memcpy(buffer, XATTR_NAME_SELINUX, len);
2718         return len;
2719 }
2720
2721 static int selinux_inode_need_killpriv(struct dentry *dentry)
2722 {
2723         return secondary_ops->inode_need_killpriv(dentry);
2724 }
2725
2726 static int selinux_inode_killpriv(struct dentry *dentry)
2727 {
2728         return secondary_ops->inode_killpriv(dentry);
2729 }
2730
2731 /* file security operations */
2732
2733 static int selinux_revalidate_file_permission(struct file *file, int mask)
2734 {
2735         int rc;
2736         struct inode *inode = file->f_path.dentry->d_inode;
2737
2738         if (!mask) {
2739                 /* No permission to check.  Existence test. */
2740                 return 0;
2741         }
2742
2743         /* file_mask_to_av won't add FILE__WRITE if MAY_APPEND is set */
2744         if ((file->f_flags & O_APPEND) && (mask & MAY_WRITE))
2745                 mask |= MAY_APPEND;
2746
2747         rc = file_has_perm(current, file,
2748                            file_mask_to_av(inode->i_mode, mask));
2749         if (rc)
2750                 return rc;
2751
2752         return selinux_netlbl_inode_permission(inode, mask);
2753 }
2754
2755 static int selinux_file_permission(struct file *file, int mask)
2756 {
2757         struct inode *inode = file->f_path.dentry->d_inode;
2758         struct task_security_struct *tsec = current->security;
2759         struct file_security_struct *fsec = file->f_security;
2760         struct inode_security_struct *isec = inode->i_security;
2761
2762         if (!mask) {
2763                 /* No permission to check.  Existence test. */
2764                 return 0;
2765         }
2766
2767         if (tsec->sid == fsec->sid && fsec->isid == isec->sid
2768             && fsec->pseqno == avc_policy_seqno())
2769                 return selinux_netlbl_inode_permission(inode, mask);
2770
2771         return selinux_revalidate_file_permission(file, mask);
2772 }
2773
2774 static int selinux_file_alloc_security(struct file *file)
2775 {
2776         return file_alloc_security(file);
2777 }
2778
2779 static void selinux_file_free_security(struct file *file)
2780 {
2781         file_free_security(file);
2782 }
2783
2784 static int selinux_file_ioctl(struct file *file, unsigned int cmd,
2785                               unsigned long arg)
2786 {
2787         int error = 0;
2788
2789         switch (cmd) {
2790                 case FIONREAD:
2791                 /* fall through */
2792                 case FIBMAP:
2793                 /* fall through */
2794                 case FIGETBSZ:
2795                 /* fall through */
2796                 case EXT2_IOC_GETFLAGS:
2797                 /* fall through */
2798                 case EXT2_IOC_GETVERSION:
2799                         error = file_has_perm(current, file, FILE__GETATTR);
2800                         break;
2801
2802                 case EXT2_IOC_SETFLAGS:
2803                 /* fall through */
2804                 case EXT2_IOC_SETVERSION:
2805                         error = file_has_perm(current, file, FILE__SETATTR);
2806                         break;
2807
2808                 /* sys_ioctl() checks */
2809                 case FIONBIO:
2810                 /* fall through */
2811                 case FIOASYNC:
2812                         error = file_has_perm(current, file, 0);
2813                         break;
2814
2815                 case KDSKBENT:
2816                 case KDSKBSENT:
2817                         error = task_has_capability(current,CAP_SYS_TTY_CONFIG);
2818                         break;
2819
2820                 /* default case assumes that the command will go
2821                  * to the file's ioctl() function.
2822                  */
2823                 default:
2824                         error = file_has_perm(current, file, FILE__IOCTL);
2825
2826         }
2827         return error;
2828 }
2829
2830 static int file_map_prot_check(struct file *file, unsigned long prot, int shared)
2831 {
2832 #ifndef CONFIG_PPC32
2833         if ((prot & PROT_EXEC) && (!file || (!shared && (prot & PROT_WRITE)))) {
2834                 /*
2835                  * We are making executable an anonymous mapping or a
2836                  * private file mapping that will also be writable.
2837                  * This has an additional check.
2838                  */
2839                 int rc = task_has_perm(current, current, PROCESS__EXECMEM);
2840                 if (rc)
2841                         return rc;
2842         }
2843 #endif
2844
2845         if (file) {
2846                 /* read access is always possible with a mapping */
2847                 u32 av = FILE__READ;
2848
2849                 /* write access only matters if the mapping is shared */
2850                 if (shared && (prot & PROT_WRITE))
2851                         av |= FILE__WRITE;
2852
2853                 if (prot & PROT_EXEC)
2854                         av |= FILE__EXECUTE;
2855
2856                 return file_has_perm(current, file, av);
2857         }
2858         return 0;
2859 }
2860
2861 static int selinux_file_mmap(struct file *file, unsigned long reqprot,
2862                              unsigned long prot, unsigned long flags,
2863                              unsigned long addr, unsigned long addr_only)
2864 {
2865         int rc = 0;
2866         u32 sid = ((struct task_security_struct*)(current->security))->sid;
2867
2868         if (addr < mmap_min_addr)
2869                 rc = avc_has_perm(sid, sid, SECCLASS_MEMPROTECT,
2870                                   MEMPROTECT__MMAP_ZERO, NULL);
2871         if (rc || addr_only)
2872                 return rc;
2873
2874         if (selinux_checkreqprot)
2875                 prot = reqprot;
2876
2877         return file_map_prot_check(file, prot,
2878                                    (flags & MAP_TYPE) == MAP_SHARED);
2879 }
2880
2881 static int selinux_file_mprotect(struct vm_area_struct *vma,
2882                                  unsigned long reqprot,
2883                                  unsigned long prot)
2884 {
2885         int rc;
2886
2887         rc = secondary_ops->file_mprotect(vma, reqprot, prot);
2888         if (rc)
2889                 return rc;
2890
2891         if (selinux_checkreqprot)
2892                 prot = reqprot;
2893
2894 #ifndef CONFIG_PPC32
2895         if ((prot & PROT_EXEC) && !(vma->vm_flags & VM_EXEC)) {
2896                 rc = 0;
2897                 if (vma->vm_start >= vma->vm_mm->start_brk &&
2898                     vma->vm_end <= vma->vm_mm->brk) {
2899                         rc = task_has_perm(current, current,
2900                                            PROCESS__EXECHEAP);
2901                 } else if (!vma->vm_file &&
2902                            vma->vm_start <= vma->vm_mm->start_stack &&
2903                            vma->vm_end >= vma->vm_mm->start_stack) {
2904                         rc = task_has_perm(current, current, PROCESS__EXECSTACK);
2905                 } else if (vma->vm_file && vma->anon_vma) {
2906                         /*
2907                          * We are making executable a file mapping that has
2908                          * had some COW done. Since pages might have been
2909                          * written, check ability to execute the possibly
2910                          * modified content.  This typically should only
2911                          * occur for text relocations.
2912                          */
2913                         rc = file_has_perm(current, vma->vm_file,
2914                                            FILE__EXECMOD);
2915                 }
2916                 if (rc)
2917                         return rc;
2918         }
2919 #endif
2920
2921         return file_map_prot_check(vma->vm_file, prot, vma->vm_flags&VM_SHARED);
2922 }
2923
2924 static int selinux_file_lock(struct file *file, unsigned int cmd)
2925 {
2926         return file_has_perm(current, file, FILE__LOCK);
2927 }
2928
2929 static int selinux_file_fcntl(struct file *file, unsigned int cmd,
2930                               unsigned long arg)
2931 {
2932         int err = 0;
2933
2934         switch (cmd) {
2935                 case F_SETFL:
2936                         if (!file->f_path.dentry || !file->f_path.dentry->d_inode) {
2937                                 err = -EINVAL;
2938                                 break;
2939                         }
2940
2941                         if ((file->f_flags & O_APPEND) && !(arg & O_APPEND)) {
2942                                 err = file_has_perm(current, file,FILE__WRITE);
2943                                 break;
2944                         }
2945                         /* fall through */
2946                 case F_SETOWN:
2947                 case F_SETSIG:
2948                 case F_GETFL:
2949                 case F_GETOWN:
2950                 case F_GETSIG:
2951                         /* Just check FD__USE permission */
2952                         err = file_has_perm(current, file, 0);
2953                         break;
2954                 case F_GETLK:
2955                 case F_SETLK:
2956                 case F_SETLKW:
2957 #if BITS_PER_LONG == 32
2958                 case F_GETLK64:
2959                 case F_SETLK64:
2960                 case F_SETLKW64:
2961 #endif
2962                         if (!file->f_path.dentry || !file->f_path.dentry->d_inode) {
2963                                 err = -EINVAL;
2964                                 break;
2965                         }
2966                         err = file_has_perm(current, file, FILE__LOCK);
2967                         break;
2968         }
2969
2970         return err;
2971 }
2972
2973 static int selinux_file_set_fowner(struct file *file)
2974 {
2975         struct task_security_struct *tsec;
2976         struct file_security_struct *fsec;
2977
2978         tsec = current->security;
2979         fsec = file->f_security;
2980         fsec->fown_sid = tsec->sid;
2981
2982         return 0;
2983 }
2984
2985 static int selinux_file_send_sigiotask(struct task_struct *tsk,
2986                                        struct fown_struct *fown, int signum)
2987 {
2988         struct file *file;
2989         u32 perm;
2990         struct task_security_struct *tsec;
2991         struct file_security_struct *fsec;
2992
2993         /* struct fown_struct is never outside the context of a struct file */
2994         file = container_of(fown, struct file, f_owner);
2995
2996         tsec = tsk->security;
2997         fsec = file->f_security;
2998
2999         if (!signum)
3000                 perm = signal_to_av(SIGIO); /* as per send_sigio_to_task */
3001         else
3002                 perm = signal_to_av(signum);
3003
3004         return avc_has_perm(fsec->fown_sid, tsec->sid,
3005                             SECCLASS_PROCESS, perm, NULL);
3006 }
3007
3008 static int selinux_file_receive(struct file *file)
3009 {
3010         return file_has_perm(current, file, file_to_av(file));
3011 }
3012
3013 static int selinux_dentry_open(struct file *file)
3014 {
3015         struct file_security_struct *fsec;
3016         struct inode *inode;
3017         struct inode_security_struct *isec;
3018         inode = file->f_path.dentry->d_inode;
3019         fsec = file->f_security;
3020         isec = inode->i_security;
3021         /*
3022          * Save inode label and policy sequence number
3023          * at open-time so that selinux_file_permission
3024          * can determine whether revalidation is necessary.
3025          * Task label is already saved in the file security
3026          * struct as its SID.
3027          */
3028         fsec->isid = isec->sid;
3029         fsec->pseqno = avc_policy_seqno();
3030         /*
3031          * Since the inode label or policy seqno may have changed
3032          * between the selinux_inode_permission check and the saving
3033          * of state above, recheck that access is still permitted.
3034          * Otherwise, access might never be revalidated against the
3035          * new inode label or new policy.
3036          * This check is not redundant - do not remove.
3037          */
3038         return inode_has_perm(current, inode, file_to_av(file), NULL);
3039 }
3040
3041 /* task security operations */
3042
3043 static int selinux_task_create(unsigned long clone_flags)
3044 {
3045         int rc;
3046
3047         rc = secondary_ops->task_create(clone_flags);
3048         if (rc)
3049                 return rc;
3050
3051         return task_has_perm(current, current, PROCESS__FORK);
3052 }
3053
3054 static int selinux_task_alloc_security(struct task_struct *tsk)
3055 {
3056         struct task_security_struct *tsec1, *tsec2;
3057         int rc;
3058
3059         tsec1 = current->security;
3060
3061         rc = task_alloc_security(tsk);
3062         if (rc)
3063                 return rc;
3064         tsec2 = tsk->security;
3065
3066         tsec2->osid = tsec1->osid;
3067         tsec2->sid = tsec1->sid;
3068
3069         /* Retain the exec, fs, key, and sock SIDs across fork */
3070         tsec2->exec_sid = tsec1->exec_sid;
3071         tsec2->create_sid = tsec1->create_sid;
3072         tsec2->keycreate_sid = tsec1->keycreate_sid;
3073         tsec2->sockcreate_sid = tsec1->sockcreate_sid;
3074
3075         /* Retain ptracer SID across fork, if any.
3076            This will be reset by the ptrace hook upon any
3077            subsequent ptrace_attach operations. */
3078         tsec2->ptrace_sid = tsec1->ptrace_sid;
3079
3080         return 0;
3081 }
3082
3083 static void selinux_task_free_security(struct task_struct *tsk)
3084 {
3085         task_free_security(tsk);
3086 }
3087
3088 static int selinux_task_setuid(uid_t id0, uid_t id1, uid_t id2, int flags)
3089 {
3090         /* Since setuid only affects the current process, and
3091            since the SELinux controls are not based on the Linux
3092            identity attributes, SELinux does not need to control
3093            this operation.  However, SELinux does control the use
3094            of the CAP_SETUID and CAP_SETGID capabilities using the
3095            capable hook. */
3096         return 0;
3097 }
3098
3099 static int selinux_task_post_setuid(uid_t id0, uid_t id1, uid_t id2, int flags)
3100 {
3101         return secondary_ops->task_post_setuid(id0,id1,id2,flags);
3102 }
3103
3104 static int selinux_task_setgid(gid_t id0, gid_t id1, gid_t id2, int flags)
3105 {
3106         /* See the comment for setuid above. */
3107         return 0;
3108 }
3109
3110 static int selinux_task_setpgid(struct task_struct *p, pid_t pgid)
3111 {
3112         return task_has_perm(current, p, PROCESS__SETPGID);
3113 }
3114
3115 static int selinux_task_getpgid(struct task_struct *p)
3116 {
3117         return task_has_perm(current, p, PROCESS__GETPGID);
3118 }
3119
3120 static int selinux_task_getsid(struct task_struct *p)
3121 {
3122         return task_has_perm(current, p, PROCESS__GETSESSION);
3123 }
3124
3125 static void selinux_task_getsecid(struct task_struct *p, u32 *secid)
3126 {
3127         selinux_get_task_sid(p, secid);
3128 }
3129
3130 static int selinux_task_setgroups(struct group_info *group_info)
3131 {
3132         /* See the comment for setuid above. */
3133         return 0;
3134 }
3135
3136 static int selinux_task_setnice(struct task_struct *p, int nice)
3137 {
3138         int rc;
3139
3140         rc = secondary_ops->task_setnice(p, nice);
3141         if (rc)
3142                 return rc;
3143
3144         return task_has_perm(current,p, PROCESS__SETSCHED);
3145 }
3146
3147 static int selinux_task_setioprio(struct task_struct *p, int ioprio)
3148 {
3149         int rc;
3150
3151         rc = secondary_ops->task_setioprio(p, ioprio);
3152         if (rc)
3153                 return rc;
3154
3155         return task_has_perm(current, p, PROCESS__SETSCHED);
3156 }
3157
3158 static int selinux_task_getioprio(struct task_struct *p)
3159 {
3160         return task_has_perm(current, p, PROCESS__GETSCHED);
3161 }
3162
3163 static int selinux_task_setrlimit(unsigned int resource, struct rlimit *new_rlim)
3164 {
3165         struct rlimit *old_rlim = current->signal->rlim + resource;
3166         int rc;
3167
3168         rc = secondary_ops->task_setrlimit(resource, new_rlim);
3169         if (rc)
3170                 return rc;
3171
3172         /* Control the ability to change the hard limit (whether
3173            lowering or raising it), so that the hard limit can
3174            later be used as a safe reset point for the soft limit
3175            upon context transitions. See selinux_bprm_apply_creds. */
3176         if (old_rlim->rlim_max != new_rlim->rlim_max)
3177                 return task_has_perm(current, current, PROCESS__SETRLIMIT);
3178
3179         return 0;
3180 }
3181
3182 static int selinux_task_setscheduler(struct task_struct *p, int policy, struct sched_param *lp)
3183 {
3184         int rc;
3185
3186         rc = secondary_ops->task_setscheduler(p, policy, lp);
3187         if (rc)
3188                 return rc;
3189
3190         return task_has_perm(current, p, PROCESS__SETSCHED);
3191 }
3192
3193 static int selinux_task_getscheduler(struct task_struct *p)
3194 {
3195         return task_has_perm(current, p, PROCESS__GETSCHED);
3196 }
3197
3198 static int selinux_task_movememory(struct task_struct *p)
3199 {
3200         return task_has_perm(current, p, PROCESS__SETSCHED);
3201 }
3202
3203 static int selinux_task_kill(struct task_struct *p, struct siginfo *info,
3204                                 int sig, u32 secid)
3205 {
3206         u32 perm;
3207         int rc;
3208         struct task_security_struct *tsec;
3209
3210         rc = secondary_ops->task_kill(p, info, sig, secid);
3211         if (rc)
3212                 return rc;
3213
3214         if (info != SEND_SIG_NOINFO && (is_si_special(info) || SI_FROMKERNEL(info)))
3215                 return 0;
3216
3217         if (!sig)
3218                 perm = PROCESS__SIGNULL; /* null signal; existence test */
3219         else
3220                 perm = signal_to_av(sig);
3221         tsec = p->security;
3222         if (secid)
3223                 rc = avc_has_perm(secid, tsec->sid, SECCLASS_PROCESS, perm, NULL);
3224         else
3225                 rc = task_has_perm(current, p, perm);
3226         return rc;
3227 }
3228
3229 static int selinux_task_prctl(int option,
3230                               unsigned long arg2,
3231                               unsigned long arg3,
3232                               unsigned long arg4,
3233                               unsigned long arg5)
3234 {
3235         /* The current prctl operations do not appear to require
3236            any SELinux controls since they merely observe or modify
3237            the state of the current process. */
3238         return 0;
3239 }
3240
3241 static int selinux_task_wait(struct task_struct *p)
3242 {
3243         return task_has_perm(p, current, PROCESS__SIGCHLD);
3244 }
3245
3246 static void selinux_task_reparent_to_init(struct task_struct *p)
3247 {
3248         struct task_security_struct *tsec;
3249
3250         secondary_ops->task_reparent_to_init(p);
3251
3252         tsec = p->security;
3253         tsec->osid = tsec->sid;
3254         tsec->sid = SECINITSID_KERNEL;
3255         return;
3256 }
3257
3258 static void selinux_task_to_inode(struct task_struct *p,
3259                                   struct inode *inode)
3260 {
3261         struct task_security_struct *tsec = p->security;
3262         struct inode_security_struct *isec = inode->i_security;
3263
3264         isec->sid = tsec->sid;
3265         isec->initialized = 1;
3266         return;
3267 }
3268
3269 /* Returns error only if unable to parse addresses */
3270 static int selinux_parse_skb_ipv4(struct sk_buff *skb,
3271                         struct avc_audit_data *ad, u8 *proto)
3272 {
3273         int offset, ihlen, ret = -EINVAL;
3274         struct iphdr _iph, *ih;
3275
3276         offset = skb_network_offset(skb);
3277         ih = skb_header_pointer(skb, offset, sizeof(_iph), &_iph);
3278         if (ih == NULL)
3279                 goto out;
3280
3281         ihlen = ih->ihl * 4;
3282         if (ihlen < sizeof(_iph))
3283                 goto out;
3284
3285         ad->u.net.v4info.saddr = ih->saddr;
3286         ad->u.net.v4info.daddr = ih->daddr;
3287         ret = 0;
3288
3289         if (proto)
3290                 *proto = ih->protocol;
3291
3292         switch (ih->protocol) {
3293         case IPPROTO_TCP: {
3294                 struct tcphdr _tcph, *th;
3295
3296                 if (ntohs(ih->frag_off) & IP_OFFSET)
3297                         break;
3298
3299                 offset += ihlen;
3300                 th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph);
3301                 if (th == NULL)
3302                         break;
3303
3304                 ad->u.net.sport = th->source;
3305                 ad->u.net.dport = th->dest;
3306                 break;
3307         }
3308
3309         case IPPROTO_UDP: {
3310                 struct udphdr _udph, *uh;
3311
3312                 if (ntohs(ih->frag_off) & IP_OFFSET)
3313                         break;
3314
3315                 offset += ihlen;
3316                 uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph);
3317                 if (uh == NULL)
3318                         break;
3319
3320                 ad->u.net.sport = uh->source;
3321                 ad->u.net.dport = uh->dest;
3322                 break;
3323         }
3324
3325         case IPPROTO_DCCP: {
3326                 struct dccp_hdr _dccph, *dh;
3327
3328                 if (ntohs(ih->frag_off) & IP_OFFSET)
3329                         break;
3330
3331                 offset += ihlen;
3332                 dh = skb_header_pointer(skb, offset, sizeof(_dccph), &_dccph);
3333                 if (dh == NULL)
3334                         break;
3335
3336                 ad->u.net.sport = dh->dccph_sport;
3337                 ad->u.net.dport = dh->dccph_dport;
3338                 break;
3339         }
3340
3341         default:
3342                 break;
3343         }
3344 out:
3345         return ret;
3346 }
3347
3348 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
3349
3350 /* Returns error only if unable to parse addresses */
3351 static int selinux_parse_skb_ipv6(struct sk_buff *skb,
3352                         struct avc_audit_data *ad, u8 *proto)
3353 {
3354         u8 nexthdr;
3355         int ret = -EINVAL, offset;
3356         struct ipv6hdr _ipv6h, *ip6;
3357
3358         offset = skb_network_offset(skb);
3359         ip6 = skb_header_pointer(skb, offset, sizeof(_ipv6h), &_ipv6h);
3360         if (ip6 == NULL)
3361                 goto out;
3362
3363         ipv6_addr_copy(&ad->u.net.v6info.saddr, &ip6->saddr);
3364         ipv6_addr_copy(&ad->u.net.v6info.daddr, &ip6->daddr);
3365         ret = 0;
3366
3367         nexthdr = ip6->nexthdr;
3368         offset += sizeof(_ipv6h);
3369         offset = ipv6_skip_exthdr(skb, offset, &nexthdr);
3370         if (offset < 0)
3371                 goto out;
3372
3373         if (proto)
3374                 *proto = nexthdr;
3375
3376         switch (nexthdr) {
3377         case IPPROTO_TCP: {
3378                 struct tcphdr _tcph, *th;
3379
3380                 th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph);
3381                 if (th == NULL)
3382                         break;
3383
3384                 ad->u.net.sport = th->source;
3385                 ad->u.net.dport = th->dest;
3386                 break;
3387         }
3388
3389         case IPPROTO_UDP: {
3390                 struct udphdr _udph, *uh;
3391
3392                 uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph);
3393                 if (uh == NULL)
3394                         break;
3395
3396                 ad->u.net.sport = uh->source;
3397                 ad->u.net.dport = uh->dest;
3398                 break;
3399         }
3400
3401         case IPPROTO_DCCP: {
3402                 struct dccp_hdr _dccph, *dh;
3403
3404                 dh = skb_header_pointer(skb, offset, sizeof(_dccph), &_dccph);
3405                 if (dh == NULL)
3406                         break;
3407
3408                 ad->u.net.sport = dh->dccph_sport;
3409                 ad->u.net.dport = dh->dccph_dport;
3410                 break;
3411         }
3412
3413         /* includes fragments */
3414         default:
3415                 break;
3416         }
3417 out:
3418         return ret;
3419 }
3420
3421 #endif /* IPV6 */
3422
3423 static int selinux_parse_skb(struct sk_buff *skb, struct avc_audit_data *ad,
3424                              char **addrp, int src, u8 *proto)
3425 {
3426         int ret = 0;
3427
3428         switch (ad->u.net.family) {
3429         case PF_INET:
3430                 ret = selinux_parse_skb_ipv4(skb, ad, proto);
3431                 if (ret || !addrp)
3432                         break;
3433                 *addrp = (char *)(src ? &ad->u.net.v4info.saddr :
3434                                         &ad->u.net.v4info.daddr);
3435                 break;
3436
3437 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
3438         case PF_INET6:
3439                 ret = selinux_parse_skb_ipv6(skb, ad, proto);
3440                 if (ret || !addrp)
3441                         break;
3442                 *addrp = (char *)(src ? &ad->u.net.v6info.saddr :
3443                                         &ad->u.net.v6info.daddr);
3444                 break;
3445 #endif  /* IPV6 */
3446         default:
3447                 break;
3448         }
3449
3450         if (unlikely(ret))
3451                 printk(KERN_WARNING
3452                        "SELinux: failure in selinux_parse_skb(),"
3453                        " unable to parse packet\n");
3454
3455         return ret;
3456 }
3457
3458 /**
3459  * selinux_skb_peerlbl_sid - Determine the peer label of a packet
3460  * @skb: the packet
3461  * @family: protocol family
3462  * @sid: the packet's peer label SID
3463  *
3464  * Description:
3465  * Check the various different forms of network peer labeling and determine
3466  * the peer label/SID for the packet; most of the magic actually occurs in
3467  * the security server function security_net_peersid_cmp().  The function
3468  * returns zero if the value in @sid is valid (although it may be SECSID_NULL)
3469  * or -EACCES if @sid is invalid due to inconsistencies with the different
3470  * peer labels.
3471  *
3472  */
3473 static int selinux_skb_peerlbl_sid(struct sk_buff *skb, u16 family, u32 *sid)
3474 {
3475         int err;
3476         u32 xfrm_sid;
3477         u32 nlbl_sid;
3478         u32 nlbl_type;
3479
3480         selinux_skb_xfrm_sid(skb, &xfrm_sid);
3481         selinux_netlbl_skbuff_getsid(skb, family, &nlbl_type, &nlbl_sid);
3482
3483         err = security_net_peersid_resolve(nlbl_sid, nlbl_type, xfrm_sid, sid);
3484         if (unlikely(err)) {
3485                 printk(KERN_WARNING
3486                        "SELinux: failure in selinux_skb_peerlbl_sid(),"
3487                        " unable to determine packet's peer label\n");
3488                 return -EACCES;
3489         }
3490
3491         return 0;
3492 }
3493
3494 /* socket security operations */
3495 static int socket_has_perm(struct task_struct *task, struct socket *sock,
3496                            u32 perms)
3497 {
3498         struct inode_security_struct *isec;
3499         struct task_security_struct *tsec;
3500         struct avc_audit_data ad;
3501         int err = 0;
3502
3503         tsec = task->security;
3504         isec = SOCK_INODE(sock)->i_security;
3505
3506         if (isec->sid == SECINITSID_KERNEL)
3507                 goto out;
3508
3509         AVC_AUDIT_DATA_INIT(&ad,NET);
3510         ad.u.net.sk = sock->sk;
3511         err = avc_has_perm(tsec->sid, isec->sid, isec->sclass, perms, &ad);
3512
3513 out:
3514         return err;
3515 }
3516
3517 static int selinux_socket_create(int family, int type,
3518                                  int protocol, int kern)
3519 {
3520         int err = 0;
3521         struct task_security_struct *tsec;
3522         u32 newsid;
3523
3524         if (kern)
3525                 goto out;
3526
3527         tsec = current->security;
3528         newsid = tsec->sockcreate_sid ? : tsec->sid;
3529         err = avc_has_perm(tsec->sid, newsid,
3530                            socket_type_to_security_class(family, type,
3531                            protocol), SOCKET__CREATE, NULL);
3532
3533 out:
3534         return err;
3535 }
3536
3537 static int selinux_socket_post_create(struct socket *sock, int family,
3538                                       int type, int protocol, int kern)
3539 {
3540         int err = 0;
3541         struct inode_security_struct *isec;
3542         struct task_security_struct *tsec;
3543         struct sk_security_struct *sksec;
3544         u32 newsid;
3545
3546         isec = SOCK_INODE(sock)->i_security;
3547
3548         tsec = current->security;
3549         newsid = tsec->sockcreate_sid ? : tsec->sid;
3550         isec->sclass = socket_type_to_security_class(family, type, protocol);
3551         isec->sid = kern ? SECINITSID_KERNEL : newsid;
3552         isec->initialized = 1;
3553
3554         if (sock->sk) {
3555                 sksec = sock->sk->sk_security;
3556                 sksec->sid = isec->sid;
3557                 sksec->sclass = isec->sclass;
3558                 err = selinux_netlbl_socket_post_create(sock);
3559         }
3560
3561         return err;
3562 }
3563
3564 /* Range of port numbers used to automatically bind.
3565    Need to determine whether we should perform a name_bind
3566    permission check between the socket and the port number. */
3567
3568 static int selinux_socket_bind(struct socket *sock, struct sockaddr *address, int addrlen)
3569 {
3570         u16 family;
3571         int err;
3572
3573         err = socket_has_perm(current, sock, SOCKET__BIND);
3574         if (err)
3575                 goto out;
3576
3577         /*
3578          * If PF_INET or PF_INET6, check name_bind permission for the port.
3579          * Multiple address binding for SCTP is not supported yet: we just
3580          * check the first address now.
3581          */
3582         family = sock->sk->sk_family;
3583         if (family == PF_INET || family == PF_INET6) {
3584                 char *addrp;
3585                 struct inode_security_struct *isec;
3586                 struct task_security_struct *tsec;
3587                 struct avc_audit_data ad;
3588                 struct sockaddr_in *addr4 = NULL;
3589                 struct sockaddr_in6 *addr6 = NULL;
3590                 unsigned short snum;
3591                 struct sock *sk = sock->sk;
3592                 u32 sid, node_perm, addrlen;
3593
3594                 tsec = current->security;
3595                 isec = SOCK_INODE(sock)->i_security;
3596
3597                 if (family == PF_INET) {
3598                         addr4 = (struct sockaddr_in *)address;
3599                         snum = ntohs(addr4->sin_port);
3600                         addrlen = sizeof(addr4->sin_addr.s_addr);
3601                         addrp = (char *)&addr4->sin_addr.s_addr;
3602                 } else {
3603                         addr6 = (struct sockaddr_in6 *)address;
3604                         snum = ntohs(addr6->sin6_port);
3605                         addrlen = sizeof(addr6->sin6_addr.s6_addr);
3606                         addrp = (char *)&addr6->sin6_addr.s6_addr;
3607                 }
3608
3609                 if (snum) {
3610                         int low, high;
3611
3612                         inet_get_local_port_range(&low, &high);
3613
3614                         if (snum < max(PROT_SOCK, low) || snum > high) {
3615                                 err = security_port_sid(sk->sk_family,
3616                                                         sk->sk_type,
3617                                                         sk->sk_protocol, snum,
3618                                                         &sid);
3619                                 if (err)
3620                                         goto out;
3621                                 AVC_AUDIT_DATA_INIT(&ad,NET);
3622                                 ad.u.net.sport = htons(snum);
3623                                 ad.u.net.family = family;
3624                                 err = avc_has_perm(isec->sid, sid,
3625                                                    isec->sclass,
3626                                                    SOCKET__NAME_BIND, &ad);
3627                                 if (err)
3628                                         goto out;
3629                         }
3630                 }
3631
3632                 switch(isec->sclass) {
3633                 case SECCLASS_TCP_SOCKET:
3634                         node_perm = TCP_SOCKET__NODE_BIND;
3635                         break;
3636
3637                 case SECCLASS_UDP_SOCKET:
3638                         node_perm = UDP_SOCKET__NODE_BIND;
3639                         break;
3640
3641                 case SECCLASS_DCCP_SOCKET:
3642                         node_perm = DCCP_SOCKET__NODE_BIND;
3643                         break;
3644
3645                 default:
3646                         node_perm = RAWIP_SOCKET__NODE_BIND;
3647                         break;
3648                 }
3649
3650                 err = sel_netnode_sid(addrp, family, &sid);
3651                 if (err)
3652                         goto out;
3653
3654                 AVC_AUDIT_DATA_INIT(&ad,NET);
3655                 ad.u.net.sport = htons(snum);
3656                 ad.u.net.family = family;
3657
3658                 if (family == PF_INET)
3659                         ad.u.net.v4info.saddr = addr4->sin_addr.s_addr;
3660                 else
3661                         ipv6_addr_copy(&ad.u.net.v6info.saddr, &addr6->sin6_addr);
3662
3663                 err = avc_has_perm(isec->sid, sid,
3664                                    isec->sclass, node_perm, &ad);
3665                 if (err)
3666                         goto out;
3667         }
3668 out:
3669         return err;
3670 }
3671
3672 static int selinux_socket_connect(struct socket *sock, struct sockaddr *address, int addrlen)
3673 {
3674         struct inode_security_struct *isec;
3675         int err;
3676
3677         err = socket_has_perm(current, sock, SOCKET__CONNECT);
3678         if (err)
3679                 return err;
3680
3681         /*
3682          * If a TCP or DCCP socket, check name_connect permission for the port.
3683          */
3684         isec = SOCK_INODE(sock)->i_security;
3685         if (isec->sclass == SECCLASS_TCP_SOCKET ||
3686             isec->sclass == SECCLASS_DCCP_SOCKET) {
3687                 struct sock *sk = sock->sk;
3688                 struct avc_audit_data ad;
3689                 struct sockaddr_in *addr4 = NULL;
3690                 struct sockaddr_in6 *addr6 = NULL;
3691                 unsigned short snum;
3692                 u32 sid, perm;
3693
3694                 if (sk->sk_family == PF_INET) {
3695                         addr4 = (struct sockaddr_in *)address;
3696                         if (addrlen < sizeof(struct sockaddr_in))
3697                                 return -EINVAL;
3698                         snum = ntohs(addr4->sin_port);
3699                 } else {
3700                         addr6 = (struct sockaddr_in6 *)address;
3701                         if (addrlen < SIN6_LEN_RFC2133)
3702                                 return -EINVAL;
3703                         snum = ntohs(addr6->sin6_port);
3704                 }
3705
3706                 err = security_port_sid(sk->sk_family, sk->sk_type,
3707                                         sk->sk_protocol, snum, &sid);
3708                 if (err)
3709                         goto out;
3710
3711                 perm = (isec->sclass == SECCLASS_TCP_SOCKET) ?
3712                        TCP_SOCKET__NAME_CONNECT : DCCP_SOCKET__NAME_CONNECT;
3713
3714                 AVC_AUDIT_DATA_INIT(&ad,NET);
3715                 ad.u.net.dport = htons(snum);
3716                 ad.u.net.family = sk->sk_family;
3717                 err = avc_has_perm(isec->sid, sid, isec->sclass, perm, &ad);
3718                 if (err)
3719                         goto out;
3720         }
3721
3722 out:
3723         return err;
3724 }
3725
3726 static int selinux_socket_listen(struct socket *sock, int backlog)
3727 {
3728         return socket_has_perm(current, sock, SOCKET__LISTEN);
3729 }
3730
3731 static int selinux_socket_accept(struct socket *sock, struct socket *newsock)
3732 {
3733         int err;
3734         struct inode_security_struct *isec;
3735         struct inode_security_struct *newisec;
3736
3737         err = socket_has_perm(current, sock, SOCKET__ACCEPT);
3738         if (err)
3739                 return err;
3740
3741         newisec = SOCK_INODE(newsock)->i_security;
3742
3743         isec = SOCK_INODE(sock)->i_security;
3744         newisec->sclass = isec->sclass;
3745         newisec->sid = isec->sid;
3746         newisec->initialized = 1;
3747
3748         return 0;
3749 }
3750
3751 static int selinux_socket_sendmsg(struct socket *sock, struct msghdr *msg,
3752                                   int size)
3753 {
3754         int rc;
3755
3756         rc = socket_has_perm(current, sock, SOCKET__WRITE);
3757         if (rc)
3758                 return rc;
3759
3760         return selinux_netlbl_inode_permission(SOCK_INODE(sock), MAY_WRITE);
3761 }
3762
3763 static int selinux_socket_recvmsg(struct socket *sock, struct msghdr *msg,
3764                                   int size, int flags)
3765 {
3766         return socket_has_perm(current, sock, SOCKET__READ);
3767 }
3768
3769 static int selinux_socket_getsockname(struct socket *sock)
3770 {
3771         return socket_has_perm(current, sock, SOCKET__GETATTR);
3772 }
3773
3774 static int selinux_socket_getpeername(struct socket *sock)
3775 {
3776         return socket_has_perm(current, sock, SOCKET__GETATTR);
3777 }
3778
3779 static int selinux_socket_setsockopt(struct socket *sock,int level,int optname)
3780 {
3781         int err;
3782
3783         err = socket_has_perm(current, sock, SOCKET__SETOPT);
3784         if (err)
3785                 return err;
3786
3787         return selinux_netlbl_socket_setsockopt(sock, level, optname);
3788 }
3789
3790 static int selinux_socket_getsockopt(struct socket *sock, int level,
3791                                      int optname)
3792 {
3793         return socket_has_perm(current, sock, SOCKET__GETOPT);
3794 }
3795
3796 static int selinux_socket_shutdown(struct socket *sock, int how)
3797 {
3798         return socket_has_perm(current, sock, SOCKET__SHUTDOWN);
3799 }
3800
3801 static int selinux_socket_unix_stream_connect(struct socket *sock,
3802                                               struct socket *other,
3803                                               struct sock *newsk)
3804 {
3805         struct sk_security_struct *ssec;
3806         struct inode_security_struct *isec;
3807         struct inode_security_struct *other_isec;
3808         struct avc_audit_data ad;
3809         int err;
3810
3811         err = secondary_ops->unix_stream_connect(sock, other, newsk);
3812         if (err)
3813                 return err;
3814
3815         isec = SOCK_INODE(sock)->i_security;
3816         other_isec = SOCK_INODE(other)->i_security;
3817
3818         AVC_AUDIT_DATA_INIT(&ad,NET);
3819         ad.u.net.sk = other->sk;
3820
3821         err = avc_has_perm(isec->sid, other_isec->sid,
3822                            isec->sclass,
3823                            UNIX_STREAM_SOCKET__CONNECTTO, &ad);
3824         if (err)
3825                 return err;
3826
3827         /* connecting socket */
3828         ssec = sock->sk->sk_security;
3829         ssec->peer_sid = other_isec->sid;
3830
3831         /* server child socket */
3832         ssec = newsk->sk_security;
3833         ssec->peer_sid = isec->sid;
3834         err = security_sid_mls_copy(other_isec->sid, ssec->peer_sid, &ssec->sid);
3835
3836         return err;
3837 }
3838
3839 static int selinux_socket_unix_may_send(struct socket *sock,
3840                                         struct socket *other)
3841 {
3842         struct inode_security_struct *isec;
3843         struct inode_security_struct *other_isec;
3844         struct avc_audit_data ad;
3845         int err;
3846
3847         isec = SOCK_INODE(sock)->i_security;
3848         other_isec = SOCK_INODE(other)->i_security;
3849
3850         AVC_AUDIT_DATA_INIT(&ad,NET);
3851         ad.u.net.sk = other->sk;
3852
3853         err = avc_has_perm(isec->sid, other_isec->sid,
3854                            isec->sclass, SOCKET__SENDTO, &ad);
3855         if (err)
3856                 return err;
3857
3858         return 0;
3859 }
3860
3861 static int selinux_inet_sys_rcv_skb(int ifindex, char *addrp, u16 family,
3862                                     u32 peer_sid,
3863                                     struct avc_audit_data *ad)
3864 {
3865         int err;
3866         u32 if_sid;
3867         u32 node_sid;
3868
3869         err = sel_netif_sid(ifindex, &if_sid);
3870         if (err)
3871                 return err;
3872         err = avc_has_perm(peer_sid, if_sid,
3873                            SECCLASS_NETIF, NETIF__INGRESS, ad);
3874         if (err)
3875                 return err;
3876
3877         err = sel_netnode_sid(addrp, family, &node_sid);
3878         if (err)
3879                 return err;
3880         return avc_has_perm(peer_sid, node_sid,
3881                             SECCLASS_NODE, NODE__RECVFROM, ad);
3882 }
3883
3884 static int selinux_sock_rcv_skb_iptables_compat(struct sock *sk,
3885                                                 struct sk_buff *skb,
3886                                                 struct avc_audit_data *ad,
3887                                                 u16 family,
3888                                                 char *addrp)
3889 {
3890         int err;
3891         struct sk_security_struct *sksec = sk->sk_security;
3892         u16 sk_class;
3893         u32 netif_perm, node_perm, recv_perm;
3894         u32 port_sid, node_sid, if_sid, sk_sid;
3895
3896         sk_sid = sksec->sid;
3897         sk_class = sksec->sclass;
3898
3899         switch (sk_class) {
3900         case SECCLASS_UDP_SOCKET:
3901                 netif_perm = NETIF__UDP_RECV;
3902                 node_perm = NODE__UDP_RECV;
3903                 recv_perm = UDP_SOCKET__RECV_MSG;
3904                 break;
3905         case SECCLASS_TCP_SOCKET:
3906                 netif_perm = NETIF__TCP_RECV;
3907                 node_perm = NODE__TCP_RECV;
3908                 recv_perm = TCP_SOCKET__RECV_MSG;
3909                 break;
3910         case SECCLASS_DCCP_SOCKET:
3911                 netif_perm = NETIF__DCCP_RECV;
3912                 node_perm = NODE__DCCP_RECV;
3913                 recv_perm = DCCP_SOCKET__RECV_MSG;
3914                 break;
3915         default:
3916                 netif_perm = NETIF__RAWIP_RECV;
3917                 node_perm = NODE__RAWIP_RECV;
3918                 recv_perm = 0;
3919                 break;
3920         }
3921
3922         err = sel_netif_sid(skb->iif, &if_sid);
3923         if (err)
3924                 return err;
3925         err = avc_has_perm(sk_sid, if_sid, SECCLASS_NETIF, netif_perm, ad);
3926         if (err)
3927                 return err;
3928
3929         err = sel_netnode_sid(addrp, family, &node_sid);
3930         if (err)
3931                 return err;
3932         err = avc_has_perm(sk_sid, node_sid, SECCLASS_NODE, node_perm, ad);
3933         if (err)
3934                 return err;
3935
3936         if (!recv_perm)
3937                 return 0;
3938         err = security_port_sid(sk->sk_family, sk->sk_type,
3939                                 sk->sk_protocol, ntohs(ad->u.net.sport),
3940                                 &port_sid);
3941         if (unlikely(err)) {
3942                 printk(KERN_WARNING
3943                        "SELinux: failure in"
3944                        " selinux_sock_rcv_skb_iptables_compat(),"
3945                        " network port label not found\n");
3946                 return err;
3947         }
3948         return avc_has_perm(sk_sid, port_sid, sk_class, recv_perm, ad);
3949 }
3950
3951 static int selinux_sock_rcv_skb_compat(struct sock *sk, struct sk_buff *skb,
3952                                        struct avc_audit_data *ad,
3953                                        u16 family, char *addrp)
3954 {
3955         int err;
3956         struct sk_security_struct *sksec = sk->sk_security;
3957         u32 peer_sid;
3958         u32 sk_sid = sksec->sid;
3959
3960         if (selinux_compat_net)
3961                 err = selinux_sock_rcv_skb_iptables_compat(sk, skb, ad,
3962                                                            family, addrp);
3963         else
3964                 err = avc_has_perm(sk_sid, skb->secmark, SECCLASS_PACKET,
3965                                    PACKET__RECV, ad);
3966         if (err)
3967                 return err;
3968
3969         if (selinux_policycap_netpeer) {
3970                 err = selinux_skb_peerlbl_sid(skb, family, &peer_sid);
3971                 if (err)
3972                         return err;
3973                 err = avc_has_perm(sk_sid, peer_sid,
3974                                    SECCLASS_PEER, PEER__RECV, ad);
3975         } else {
3976                 err = selinux_netlbl_sock_rcv_skb(sksec, skb, family, ad);
3977                 if (err)
3978                         return err;
3979                 err = selinux_xfrm_sock_rcv_skb(sksec->sid, skb, ad);
3980         }
3981
3982         return err;
3983 }
3984
3985 static int selinux_socket_sock_rcv_skb(struct sock *sk, struct sk_buff *skb)
3986 {
3987         int err;
3988         struct sk_security_struct *sksec = sk->sk_security;
3989         u16 family = sk->sk_family;
3990         u32 sk_sid = sksec->sid;
3991         struct avc_audit_data ad;
3992         char *addrp;
3993
3994         if (family != PF_INET && family != PF_INET6)
3995                 return 0;
3996
3997         /* Handle mapped IPv4 packets arriving via IPv6 sockets */
3998         if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
3999                 family = PF_INET;
4000
4001         AVC_AUDIT_DATA_INIT(&ad, NET);
4002         ad.u.net.netif = skb->iif;
4003         ad.u.net.family = family;
4004         err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL);
4005         if (err)
4006                 return err;
4007
4008         /* If any sort of compatibility mode is enabled then handoff processing
4009          * to the selinux_sock_rcv_skb_compat() function to deal with the
4010          * special handling.  We do this in an attempt to keep this function
4011          * as fast and as clean as possible. */
4012         if (selinux_compat_net || !selinux_policycap_netpeer)
4013                 return selinux_sock_rcv_skb_compat(sk, skb, &ad,
4014                                                    family, addrp);
4015
4016         if (netlbl_enabled() || selinux_xfrm_enabled()) {
4017                 u32 peer_sid;
4018
4019                 err = selinux_skb_peerlbl_sid(skb, family, &peer_sid);
4020                 if (err)
4021                         return err;
4022                 err = selinux_inet_sys_rcv_skb(skb->iif, addrp, family,
4023                                                peer_sid, &ad);
4024                 if (err)
4025                         return err;
4026                 err = avc_has_perm(sk_sid, peer_sid, SECCLASS_PEER,
4027                                    PEER__RECV, &ad);
4028         }
4029
4030         if (selinux_secmark_enabled()) {
4031                 err = avc_has_perm(sk_sid, skb->secmark, SECCLASS_PACKET,
4032                                    PACKET__RECV, &ad);
4033                 if (err)
4034                         return err;
4035         }
4036
4037         return err;
4038 }
4039
4040 static int selinux_socket_getpeersec_stream(struct socket *sock, char __user *optval,
4041                                             int __user *optlen, unsigned len)
4042 {
4043         int err = 0;
4044         char *scontext;
4045         u32 scontext_len;
4046         struct sk_security_struct *ssec;
4047         struct inode_security_struct *isec;
4048         u32 peer_sid = SECSID_NULL;
4049
4050         isec = SOCK_INODE(sock)->i_security;
4051
4052         if (isec->sclass == SECCLASS_UNIX_STREAM_SOCKET ||
4053             isec->sclass == SECCLASS_TCP_SOCKET) {
4054                 ssec = sock->sk->sk_security;
4055                 peer_sid = ssec->peer_sid;
4056         }
4057         if (peer_sid == SECSID_NULL) {
4058                 err = -ENOPROTOOPT;
4059                 goto out;
4060         }
4061
4062         err = security_sid_to_context(peer_sid, &scontext, &scontext_len);
4063
4064         if (err)
4065                 goto out;
4066
4067         if (scontext_len > len) {
4068                 err = -ERANGE;
4069                 goto out_len;
4070         }
4071
4072         if (copy_to_user(optval, scontext, scontext_len))
4073                 err = -EFAULT;
4074
4075 out_len:
4076         if (put_user(scontext_len, optlen))
4077                 err = -EFAULT;
4078
4079         kfree(scontext);
4080 out:
4081         return err;
4082 }
4083
4084 static int selinux_socket_getpeersec_dgram(struct socket *sock, struct sk_buff *skb, u32 *secid)
4085 {
4086         u32 peer_secid = SECSID_NULL;
4087         u16 family;
4088
4089         if (sock)
4090                 family = sock->sk->sk_family;
4091         else if (skb && skb->sk)
4092                 family = skb->sk->sk_family;
4093         else
4094                 goto out;
4095
4096         if (sock && family == PF_UNIX)
4097                 selinux_get_inode_sid(SOCK_INODE(sock), &peer_secid);
4098         else if (skb)
4099                 selinux_skb_peerlbl_sid(skb, family, &peer_secid);
4100
4101 out:
4102         *secid = peer_secid;
4103         if (peer_secid == SECSID_NULL)
4104                 return -EINVAL;
4105         return 0;
4106 }
4107
4108 static int selinux_sk_alloc_security(struct sock *sk, int family, gfp_t priority)
4109 {
4110         return sk_alloc_security(sk, family, priority);
4111 }
4112
4113 static void selinux_sk_free_security(struct sock *sk)
4114 {
4115         sk_free_security(sk);
4116 }
4117
4118 static void selinux_sk_clone_security(const struct sock *sk, struct sock *newsk)
4119 {
4120         struct sk_security_struct *ssec = sk->sk_security;
4121         struct sk_security_struct *newssec = newsk->sk_security;
4122
4123         newssec->sid = ssec->sid;
4124         newssec->peer_sid = ssec->peer_sid;
4125         newssec->sclass = ssec->sclass;
4126
4127         selinux_netlbl_sk_security_clone(ssec, newssec);
4128 }
4129
4130 static void selinux_sk_getsecid(struct sock *sk, u32 *secid)
4131 {
4132         if (!sk)
4133                 *secid = SECINITSID_ANY_SOCKET;
4134         else {
4135                 struct sk_security_struct *sksec = sk->sk_security;
4136
4137                 *secid = sksec->sid;
4138         }
4139 }
4140
4141 static void selinux_sock_graft(struct sock* sk, struct socket *parent)
4142 {
4143         struct inode_security_struct *isec = SOCK_INODE(parent)->i_security;
4144         struct sk_security_struct *sksec = sk->sk_security;
4145
4146         if (sk->sk_family == PF_INET || sk->sk_family == PF_INET6 ||
4147             sk->sk_family == PF_UNIX)
4148                 isec->sid = sksec->sid;
4149         sksec->sclass = isec->sclass;
4150
4151         selinux_netlbl_sock_graft(sk, parent);
4152 }
4153
4154 static int selinux_inet_conn_request(struct sock *sk, struct sk_buff *skb,
4155                                      struct request_sock *req)
4156 {
4157         struct sk_security_struct *sksec = sk->sk_security;
4158         int err;
4159         u32 newsid;
4160         u32 peersid;
4161
4162         err = selinux_skb_peerlbl_sid(skb, sk->sk_family, &peersid);
4163         if (err)
4164                 return err;
4165         if (peersid == SECSID_NULL) {
4166                 req->secid = sksec->sid;
4167                 req->peer_secid = SECSID_NULL;
4168                 return 0;
4169         }
4170
4171         err = security_sid_mls_copy(sksec->sid, peersid, &newsid);
4172         if (err)
4173                 return err;
4174
4175         req->secid = newsid;
4176         req->peer_secid = peersid;
4177         return 0;
4178 }
4179
4180 static void selinux_inet_csk_clone(struct sock *newsk,
4181                                    const struct request_sock *req)
4182 {
4183         struct sk_security_struct *newsksec = newsk->sk_security;
4184
4185         newsksec->sid = req->secid;
4186         newsksec->peer_sid = req->peer_secid;
4187         /* NOTE: Ideally, we should also get the isec->sid for the
4188            new socket in sync, but we don't have the isec available yet.
4189            So we will wait until sock_graft to do it, by which
4190            time it will have been created and available. */
4191
4192         /* We don't need to take any sort of lock here as we are the only
4193          * thread with access to newsksec */
4194         selinux_netlbl_sk_security_reset(newsksec, req->rsk_ops->family);
4195 }
4196
4197 static void selinux_inet_conn_established(struct sock *sk,
4198                                 struct sk_buff *skb)
4199 {
4200         struct sk_security_struct *sksec = sk->sk_security;
4201
4202         selinux_skb_peerlbl_sid(skb, sk->sk_family, &sksec->peer_sid);
4203 }
4204
4205 static void selinux_req_classify_flow(const struct request_sock *req,
4206                                       struct flowi *fl)
4207 {
4208         fl->secid = req->secid;
4209 }
4210
4211 static int selinux_nlmsg_perm(struct sock *sk, struct sk_buff *skb)
4212 {
4213         int err = 0;
4214         u32 perm;
4215         struct nlmsghdr *nlh;
4216         struct socket *sock = sk->sk_socket;
4217         struct inode_security_struct *isec = SOCK_INODE(sock)->i_security;
4218
4219         if (skb->len < NLMSG_SPACE(0)) {
4220                 err = -EINVAL;
4221                 goto out;
4222         }
4223         nlh = nlmsg_hdr(skb);
4224
4225         err = selinux_nlmsg_lookup(isec->sclass, nlh->nlmsg_type, &perm);
4226         if (err) {
4227                 if (err == -EINVAL) {
4228                         audit_log(current->audit_context, GFP_KERNEL, AUDIT_SELINUX_ERR,
4229                                   "SELinux:  unrecognized netlink message"
4230                                   " type=%hu for sclass=%hu\n",
4231                                   nlh->nlmsg_type, isec->sclass);
4232                         if (!selinux_enforcing)
4233                                 err = 0;
4234                 }
4235
4236                 /* Ignore */
4237                 if (err == -ENOENT)
4238                         err = 0;
4239                 goto out;
4240         }
4241
4242         err = socket_has_perm(current, sock, perm);
4243 out:
4244         return err;
4245 }
4246
4247 #ifdef CONFIG_NETFILTER
4248
4249 static unsigned int selinux_ip_forward(struct sk_buff *skb, int ifindex,
4250                                        u16 family)
4251 {
4252         char *addrp;
4253         u32 peer_sid;
4254         struct avc_audit_data ad;
4255         u8 secmark_active;
4256         u8 peerlbl_active;
4257
4258         if (!selinux_policycap_netpeer)
4259                 return NF_ACCEPT;
4260
4261         secmark_active = selinux_secmark_enabled();
4262         peerlbl_active = netlbl_enabled() || selinux_xfrm_enabled();
4263         if (!secmark_active && !peerlbl_active)
4264                 return NF_ACCEPT;
4265
4266         AVC_AUDIT_DATA_INIT(&ad, NET);
4267         ad.u.net.netif = ifindex;
4268         ad.u.net.family = family;
4269         if (selinux_parse_skb(skb, &ad, &addrp, 1, NULL) != 0)
4270                 return NF_DROP;
4271
4272         if (selinux_skb_peerlbl_sid(skb, family, &peer_sid) != 0)
4273                 return NF_DROP;
4274
4275         if (peerlbl_active)
4276                 if (selinux_inet_sys_rcv_skb(ifindex, addrp, family,
4277                                              peer_sid, &ad) != 0)
4278                         return NF_DROP;
4279
4280         if (secmark_active)
4281                 if (avc_has_perm(peer_sid, skb->secmark,
4282                                  SECCLASS_PACKET, PACKET__FORWARD_IN, &ad))
4283                         return NF_DROP;
4284
4285         return NF_ACCEPT;
4286 }
4287
4288 static unsigned int selinux_ipv4_forward(unsigned int hooknum,
4289                                          struct sk_buff *skb,
4290                                          const struct net_device *in,
4291                                          const struct net_device *out,
4292                                          int (*okfn)(struct sk_buff *))
4293 {
4294         return selinux_ip_forward(skb, in->ifindex, PF_INET);
4295 }
4296
4297 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
4298 static unsigned int selinux_ipv6_forward(unsigned int hooknum,
4299                                          struct sk_buff *skb,
4300                                          const struct net_device *in,
4301                                          const struct net_device *out,
4302                                          int (*okfn)(struct sk_buff *))
4303 {
4304         return selinux_ip_forward(skb, in->ifindex, PF_INET6);
4305 }
4306 #endif  /* IPV6 */
4307
4308 static int selinux_ip_postroute_iptables_compat(struct sock *sk,
4309                                                 int ifindex,
4310                                                 struct avc_audit_data *ad,
4311                                                 u16 family, char *addrp)
4312 {
4313         int err;
4314         struct sk_security_struct *sksec = sk->sk_security;
4315         u16 sk_class;
4316         u32 netif_perm, node_perm, send_perm;
4317         u32 port_sid, node_sid, if_sid, sk_sid;
4318
4319         sk_sid = sksec->sid;
4320         sk_class = sksec->sclass;
4321
4322         switch (sk_class) {
4323         case SECCLASS_UDP_SOCKET:
4324                 netif_perm = NETIF__UDP_SEND;
4325                 node_perm = NODE__UDP_SEND;
4326                 send_perm = UDP_SOCKET__SEND_MSG;
4327                 break;
4328         case SECCLASS_TCP_SOCKET:
4329                 netif_perm = NETIF__TCP_SEND;
4330                 node_perm = NODE__TCP_SEND;
4331                 send_perm = TCP_SOCKET__SEND_MSG;
4332                 break;
4333         case SECCLASS_DCCP_SOCKET:
4334                 netif_perm = NETIF__DCCP_SEND;
4335                 node_perm = NODE__DCCP_SEND;
4336                 send_perm = DCCP_SOCKET__SEND_MSG;
4337                 break;
4338         default:
4339                 netif_perm = NETIF__RAWIP_SEND;
4340                 node_perm = NODE__RAWIP_SEND;
4341                 send_perm = 0;
4342                 break;
4343         }
4344
4345         err = sel_netif_sid(ifindex, &if_sid);
4346         if (err)
4347                 return err;
4348         err = avc_has_perm(sk_sid, if_sid, SECCLASS_NETIF, netif_perm, ad);
4349                 return err;
4350
4351         err = sel_netnode_sid(addrp, family, &node_sid);
4352         if (err)
4353                 return err;
4354         err = avc_has_perm(sk_sid, node_sid, SECCLASS_NODE, node_perm, ad);
4355         if (err)
4356                 return err;
4357
4358         if (send_perm != 0)
4359                 return 0;
4360
4361         err = security_port_sid(sk->sk_family, sk->sk_type,
4362                                 sk->sk_protocol, ntohs(ad->u.net.dport),
4363                                 &port_sid);
4364         if (unlikely(err)) {
4365                 printk(KERN_WARNING
4366                        "SELinux: failure in"
4367                        " selinux_ip_postroute_iptables_compat(),"
4368                        " network port label not found\n");
4369                 return err;
4370         }
4371         return avc_has_perm(sk_sid, port_sid, sk_class, send_perm, ad);
4372 }
4373
4374 static unsigned int selinux_ip_postroute_compat(struct sk_buff *skb,
4375                                                 int ifindex,
4376                                                 struct avc_audit_data *ad,
4377                                                 u16 family,
4378                                                 char *addrp,
4379                                                 u8 proto)
4380 {
4381         struct sock *sk = skb->sk;
4382         struct sk_security_struct *sksec;
4383
4384         if (sk == NULL)
4385                 return NF_ACCEPT;
4386         sksec = sk->sk_security;
4387
4388         if (selinux_compat_net) {
4389                 if (selinux_ip_postroute_iptables_compat(skb->sk, ifindex,
4390                                                          ad, family, addrp))
4391                         return NF_DROP;
4392         } else {
4393                 if (avc_has_perm(sksec->sid, skb->secmark,
4394                                  SECCLASS_PACKET, PACKET__SEND, ad))
4395                         return NF_DROP;
4396         }
4397
4398         if (selinux_policycap_netpeer)
4399                 if (selinux_xfrm_postroute_last(sksec->sid, skb, ad, proto))
4400                         return NF_DROP;
4401
4402         return NF_ACCEPT;
4403 }
4404
4405 static unsigned int selinux_ip_postroute(struct sk_buff *skb, int ifindex,
4406                                          u16 family)
4407 {
4408         u32 secmark_perm;
4409         u32 peer_sid;
4410         struct sock *sk;
4411         struct avc_audit_data ad;
4412         char *addrp;
4413         u8 proto;
4414         u8 secmark_active;
4415         u8 peerlbl_active;
4416
4417         AVC_AUDIT_DATA_INIT(&ad, NET);
4418         ad.u.net.netif = ifindex;
4419         ad.u.net.family = family;
4420         if (selinux_parse_skb(skb, &ad, &addrp, 0, &proto))
4421                 return NF_DROP;
4422
4423         /* If any sort of compatibility mode is enabled then handoff processing
4424          * to the selinux_ip_postroute_compat() function to deal with the
4425          * special handling.  We do this in an attempt to keep this function
4426          * as fast and as clean as possible. */
4427         if (selinux_compat_net || !selinux_policycap_netpeer)
4428                 return selinux_ip_postroute_compat(skb, ifindex, &ad,
4429                                                    family, addrp, proto);
4430
4431         /* If skb->dst->xfrm is non-NULL then the packet is undergoing an IPsec
4432          * packet transformation so allow the packet to pass without any checks
4433          * since we'll have another chance to perform access control checks
4434          * when the packet is on it's final way out.
4435          * NOTE: there appear to be some IPv6 multicast cases where skb->dst
4436          *       is NULL, in this case go ahead and apply access control. */
4437         if (skb->dst != NULL && skb->dst->xfrm != NULL)
4438                 return NF_ACCEPT;
4439
4440         secmark_active = selinux_secmark_enabled();
4441         peerlbl_active = netlbl_enabled() || selinux_xfrm_enabled();
4442         if (!secmark_active && !peerlbl_active)
4443                 return NF_ACCEPT;
4444
4445         /* if the packet is locally generated (skb->sk != NULL) then use the
4446          * socket's label as the peer label, otherwise the packet is being
4447          * forwarded through this system and we need to fetch the peer label
4448          * directly from the packet */
4449         sk = skb->sk;
4450         if (sk) {
4451                 struct sk_security_struct *sksec = sk->sk_security;
4452                 peer_sid = sksec->sid;
4453                 secmark_perm = PACKET__SEND;
4454         } else {
4455                 if (selinux_skb_peerlbl_sid(skb, family, &peer_sid))
4456                                 return NF_DROP;
4457                 secmark_perm = PACKET__FORWARD_OUT;
4458         }
4459
4460         if (secmark_active)
4461                 if (avc_has_perm(peer_sid, skb->secmark,
4462                                  SECCLASS_PACKET, secmark_perm, &ad))
4463                         return NF_DROP;
4464
4465         if (peerlbl_active) {
4466                 u32 if_sid;
4467                 u32 node_sid;
4468
4469                 if (sel_netif_sid(ifindex, &if_sid))
4470                         return NF_DROP;
4471                 if (avc_has_perm(peer_sid, if_sid,
4472                                  SECCLASS_NETIF, NETIF__EGRESS, &ad))
4473                         return NF_DROP;
4474
4475                 if (sel_netnode_sid(addrp, family, &node_sid))
4476                         return NF_DROP;
4477                 if (avc_has_perm(peer_sid, node_sid,
4478                                  SECCLASS_NODE, NODE__SENDTO, &ad))
4479                         return NF_DROP;
4480         }
4481
4482         return NF_ACCEPT;
4483 }
4484
4485 static unsigned int selinux_ipv4_postroute(unsigned int hooknum,
4486                                            struct sk_buff *skb,
4487                                            const struct net_device *in,
4488                                            const struct net_device *out,
4489                                            int (*okfn)(struct sk_buff *))
4490 {
4491         return selinux_ip_postroute(skb, out->ifindex, PF_INET);
4492 }
4493
4494 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
4495 static unsigned int selinux_ipv6_postroute(unsigned int hooknum,
4496                                            struct sk_buff *skb,
4497                                            const struct net_device *in,
4498                                            const struct net_device *out,
4499                                            int (*okfn)(struct sk_buff *))
4500 {
4501         return selinux_ip_postroute(skb, out->ifindex, PF_INET6);
4502 }
4503 #endif  /* IPV6 */
4504
4505 #endif  /* CONFIG_NETFILTER */
4506
4507 static int selinux_netlink_send(struct sock *sk, struct sk_buff *skb)
4508 {
4509         int err;
4510
4511         err = secondary_ops->netlink_send(sk, skb);
4512         if (err)
4513                 return err;
4514
4515         if (policydb_loaded_version >= POLICYDB_VERSION_NLCLASS)
4516                 err = selinux_nlmsg_perm(sk, skb);
4517
4518         return err;
4519 }
4520
4521 static int selinux_netlink_recv(struct sk_buff *skb, int capability)
4522 {
4523         int err;
4524         struct avc_audit_data ad;
4525
4526         err = secondary_ops->netlink_recv(skb, capability);
4527         if (err)
4528                 return err;
4529
4530         AVC_AUDIT_DATA_INIT(&ad, CAP);
4531         ad.u.cap = capability;
4532
4533         return avc_has_perm(NETLINK_CB(skb).sid, NETLINK_CB(skb).sid,
4534                             SECCLASS_CAPABILITY, CAP_TO_MASK(capability), &ad);
4535 }
4536
4537 static int ipc_alloc_security(struct task_struct *task,
4538                               struct kern_ipc_perm *perm,
4539                               u16 sclass)
4540 {
4541         struct task_security_struct *tsec = task->security;
4542         struct ipc_security_struct *isec;
4543
4544         isec = kzalloc(sizeof(struct ipc_security_struct), GFP_KERNEL);
4545         if (!isec)
4546                 return -ENOMEM;
4547
4548         isec->sclass = sclass;
4549         isec->ipc_perm = perm;
4550         isec->sid = tsec->sid;
4551         perm->security = isec;
4552
4553         return 0;
4554 }
4555
4556 static void ipc_free_security(struct kern_ipc_perm *perm)
4557 {
4558         struct ipc_security_struct *isec = perm->security;
4559         perm->security = NULL;
4560         kfree(isec);
4561 }
4562
4563 static int msg_msg_alloc_security(struct msg_msg *msg)
4564 {
4565         struct msg_security_struct *msec;
4566
4567         msec = kzalloc(sizeof(struct msg_security_struct), GFP_KERNEL);
4568         if (!msec)
4569                 return -ENOMEM;
4570
4571         msec->msg = msg;
4572         msec->sid = SECINITSID_UNLABELED;
4573         msg->security = msec;
4574
4575         return 0;
4576 }
4577
4578 static void msg_msg_free_security(struct msg_msg *msg)
4579 {
4580         struct msg_security_struct *msec = msg->security;
4581
4582         msg->security = NULL;
4583         kfree(msec);
4584 }
4585
4586 static int ipc_has_perm(struct kern_ipc_perm *ipc_perms,
4587                         u32 perms)
4588 {
4589         struct task_security_struct *tsec;
4590         struct ipc_security_struct *isec;
4591         struct avc_audit_data ad;
4592
4593         tsec = current->security;
4594         isec = ipc_perms->security;
4595
4596         AVC_AUDIT_DATA_INIT(&ad, IPC);
4597         ad.u.ipc_id = ipc_perms->key;
4598
4599         return avc_has_perm(tsec->sid, isec->sid, isec->sclass, perms, &ad);
4600 }
4601
4602 static int selinux_msg_msg_alloc_security(struct msg_msg *msg)
4603 {
4604         return msg_msg_alloc_security(msg);
4605 }
4606
4607 static void selinux_msg_msg_free_security(struct msg_msg *msg)
4608 {
4609         msg_msg_free_security(msg);
4610 }
4611
4612 /* message queue security operations */
4613 static int selinux_msg_queue_alloc_security(struct msg_queue *msq)
4614 {
4615         struct task_security_struct *tsec;
4616         struct ipc_security_struct *isec;
4617         struct avc_audit_data ad;
4618         int rc;
4619
4620         rc = ipc_alloc_security(current, &msq->q_perm, SECCLASS_MSGQ);
4621         if (rc)
4622                 return rc;
4623
4624         tsec = current->security;
4625         isec = msq->q_perm.security;
4626
4627         AVC_AUDIT_DATA_INIT(&ad, IPC);
4628         ad.u.ipc_id = msq->q_perm.key;
4629
4630         rc = avc_has_perm(tsec->sid, isec->sid, SECCLASS_MSGQ,
4631                           MSGQ__CREATE, &ad);
4632         if (rc) {
4633                 ipc_free_security(&msq->q_perm);
4634                 return rc;
4635         }
4636         return 0;
4637 }
4638
4639 static void selinux_msg_queue_free_security(struct msg_queue *msq)
4640 {
4641         ipc_free_security(&msq->q_perm);
4642 }
4643
4644 static int selinux_msg_queue_associate(struct msg_queue *msq, int msqflg)
4645 {
4646         struct task_security_struct *tsec;
4647         struct ipc_security_struct *isec;
4648         struct avc_audit_data ad;
4649
4650         tsec = current->security;
4651         isec = msq->q_perm.security;
4652
4653         AVC_AUDIT_DATA_INIT(&ad, IPC);
4654         ad.u.ipc_id = msq->q_perm.key;
4655
4656         return avc_has_perm(tsec->sid, isec->sid, SECCLASS_MSGQ,
4657                             MSGQ__ASSOCIATE, &ad);
4658 }
4659
4660 static int selinux_msg_queue_msgctl(struct msg_queue *msq, int cmd)
4661 {
4662         int err;
4663         int perms;
4664
4665         switch(cmd) {
4666         case IPC_INFO:
4667         case MSG_INFO:
4668                 /* No specific object, just general system-wide information. */
4669                 return task_has_system(current, SYSTEM__IPC_INFO);
4670         case IPC_STAT:
4671         case MSG_STAT:
4672                 perms = MSGQ__GETATTR | MSGQ__ASSOCIATE;
4673                 break;
4674         case IPC_SET:
4675                 perms = MSGQ__SETATTR;
4676                 break;
4677         case IPC_RMID:
4678                 perms = MSGQ__DESTROY;
4679                 break;
4680         default:
4681                 return 0;
4682         }
4683
4684         err = ipc_has_perm(&msq->q_perm, perms);
4685         return err;
4686 }
4687
4688 static int selinux_msg_queue_msgsnd(struct msg_queue *msq, struct msg_msg *msg, int msqflg)
4689 {
4690         struct task_security_struct *tsec;
4691         struct ipc_security_struct *isec;
4692         struct msg_security_struct *msec;
4693         struct avc_audit_data ad;
4694         int rc;
4695
4696         tsec = current->security;
4697         isec = msq->q_perm.security;
4698         msec = msg->security;
4699
4700         /*
4701          * First time through, need to assign label to the message
4702          */
4703         if (msec->sid == SECINITSID_UNLABELED) {
4704                 /*
4705                  * Compute new sid based on current process and
4706                  * message queue this message will be stored in
4707                  */
4708                 rc = security_transition_sid(tsec->sid,
4709                                              isec->sid,
4710                                              SECCLASS_MSG,
4711                                              &msec->sid);
4712                 if (rc)
4713                         return rc;
4714         }
4715
4716         AVC_AUDIT_DATA_INIT(&ad, IPC);
4717         ad.u.ipc_id = msq->q_perm.key;
4718
4719         /* Can this process write to the queue? */
4720         rc = avc_has_perm(tsec->sid, isec->sid, SECCLASS_MSGQ,
4721                           MSGQ__WRITE, &ad);
4722         if (!rc)
4723                 /* Can this process send the message */
4724                 rc = avc_has_perm(tsec->sid, msec->sid,
4725                                   SECCLASS_MSG, MSG__SEND, &ad);
4726         if (!rc)
4727                 /* Can the message be put in the queue? */
4728                 rc = avc_has_perm(msec->sid, isec->sid,
4729                                   SECCLASS_MSGQ, MSGQ__ENQUEUE, &ad);
4730
4731         return rc;
4732 }
4733
4734 static int selinux_msg_queue_msgrcv(struct msg_queue *msq, struct msg_msg *msg,
4735                                     struct task_struct *target,
4736                                     long type, int mode)
4737 {
4738         struct task_security_struct *tsec;
4739         struct ipc_security_struct *isec;
4740         struct msg_security_struct *msec;
4741         struct avc_audit_data ad;
4742         int rc;
4743
4744         tsec = target->security;
4745         isec = msq->q_perm.security;
4746         msec = msg->security;
4747
4748         AVC_AUDIT_DATA_INIT(&ad, IPC);
4749         ad.u.ipc_id = msq->q_perm.key;
4750
4751         rc = avc_has_perm(tsec->sid, isec->sid,
4752                           SECCLASS_MSGQ, MSGQ__READ, &ad);
4753         if (!rc)
4754                 rc = avc_has_perm(tsec->sid, msec->sid,
4755                                   SECCLASS_MSG, MSG__RECEIVE, &ad);
4756         return rc;
4757 }
4758
4759 /* Shared Memory security operations */
4760 static int selinux_shm_alloc_security(struct shmid_kernel *shp)
4761 {
4762         struct task_security_struct *tsec;
4763         struct ipc_security_struct *isec;
4764         struct avc_audit_data ad;
4765         int rc;
4766
4767         rc = ipc_alloc_security(current, &shp->shm_perm, SECCLASS_SHM);
4768         if (rc)
4769                 return rc;
4770
4771         tsec = current->security;
4772         isec = shp->shm_perm.security;
4773
4774         AVC_AUDIT_DATA_INIT(&ad, IPC);
4775         ad.u.ipc_id = shp->shm_perm.key;
4776
4777         rc = avc_has_perm(tsec->sid, isec->sid, SECCLASS_SHM,
4778                           SHM__CREATE, &ad);
4779         if (rc) {
4780                 ipc_free_security(&shp->shm_perm);
4781                 return rc;
4782         }
4783         return 0;
4784 }
4785
4786 static void selinux_shm_free_security(struct shmid_kernel *shp)
4787 {
4788         ipc_free_security(&shp->shm_perm);
4789 }
4790
4791 static int selinux_shm_associate(struct shmid_kernel *shp, int shmflg)
4792 {
4793         struct task_security_struct *tsec;
4794         struct ipc_security_struct *isec;
4795         struct avc_audit_data ad;
4796
4797         tsec = current->security;
4798         isec = shp->shm_perm.security;
4799
4800         AVC_AUDIT_DATA_INIT(&ad, IPC);
4801         ad.u.ipc_id = shp->shm_perm.key;
4802
4803         return avc_has_perm(tsec->sid, isec->sid, SECCLASS_SHM,
4804                             SHM__ASSOCIATE, &ad);
4805 }
4806
4807 /* Note, at this point, shp is locked down */
4808 static int selinux_shm_shmctl(struct shmid_kernel *shp, int cmd)
4809 {
4810         int perms;
4811         int err;
4812
4813         switch(cmd) {
4814         case IPC_INFO:
4815         case SHM_INFO:
4816                 /* No specific object, just general system-wide information. */
4817                 return task_has_system(current, SYSTEM__IPC_INFO);
4818         case IPC_STAT:
4819         case SHM_STAT:
4820                 perms = SHM__GETATTR | SHM__ASSOCIATE;
4821                 break;
4822         case IPC_SET:
4823                 perms = SHM__SETATTR;
4824                 break;
4825         case SHM_LOCK:
4826         case SHM_UNLOCK:
4827                 perms = SHM__LOCK;
4828                 break;
4829         case IPC_RMID:
4830                 perms = SHM__DESTROY;
4831                 break;
4832         default:
4833                 return 0;
4834         }
4835
4836         err = ipc_has_perm(&shp->shm_perm, perms);
4837         return err;
4838 }
4839
4840 static int selinux_shm_shmat(struct shmid_kernel *shp,
4841                              char __user *shmaddr, int shmflg)
4842 {
4843         u32 perms;
4844         int rc;
4845
4846         rc = secondary_ops->shm_shmat(shp, shmaddr, shmflg);
4847         if (rc)
4848                 return rc;
4849
4850         if (shmflg & SHM_RDONLY)
4851                 perms = SHM__READ;
4852         else
4853                 perms = SHM__READ | SHM__WRITE;
4854
4855         return ipc_has_perm(&shp->shm_perm, perms);
4856 }
4857
4858 /* Semaphore security operations */
4859 static int selinux_sem_alloc_security(struct sem_array *sma)
4860 {
4861         struct task_security_struct *tsec;
4862         struct ipc_security_struct *isec;
4863         struct avc_audit_data ad;
4864         int rc;
4865
4866         rc = ipc_alloc_security(current, &sma->sem_perm, SECCLASS_SEM);
4867         if (rc)
4868                 return rc;
4869
4870         tsec = current->security;
4871         isec = sma->sem_perm.security;
4872
4873         AVC_AUDIT_DATA_INIT(&ad, IPC);
4874         ad.u.ipc_id = sma->sem_perm.key;
4875
4876         rc = avc_has_perm(tsec->sid, isec->sid, SECCLASS_SEM,
4877                           SEM__CREATE, &ad);
4878         if (rc) {
4879                 ipc_free_security(&sma->sem_perm);
4880                 return rc;
4881         }
4882         return 0;
4883 }
4884
4885 static void selinux_sem_free_security(struct sem_array *sma)
4886 {
4887         ipc_free_security(&sma->sem_perm);
4888 }
4889
4890 static int selinux_sem_associate(struct sem_array *sma, int semflg)
4891 {
4892         struct task_security_struct *tsec;
4893         struct ipc_security_struct *isec;
4894         struct avc_audit_data ad;
4895
4896         tsec = current->security;
4897         isec = sma->sem_perm.security;
4898
4899         AVC_AUDIT_DATA_INIT(&ad, IPC);
4900         ad.u.ipc_id = sma->sem_perm.key;
4901
4902         return avc_has_perm(tsec->sid, isec->sid, SECCLASS_SEM,
4903                             SEM__ASSOCIATE, &ad);
4904 }
4905
4906 /* Note, at this point, sma is locked down */
4907 static int selinux_sem_semctl(struct sem_array *sma, int cmd)
4908 {
4909         int err;
4910         u32 perms;
4911
4912         switch(cmd) {
4913         case IPC_INFO:
4914         case SEM_INFO:
4915                 /* No specific object, just general system-wide information. */
4916                 return task_has_system(current, SYSTEM__IPC_INFO);
4917         case GETPID:
4918         case GETNCNT:
4919         case GETZCNT:
4920                 perms = SEM__GETATTR;
4921                 break;
4922         case GETVAL:
4923         case GETALL:
4924                 perms = SEM__READ;
4925                 break;
4926         case SETVAL:
4927         case SETALL:
4928                 perms = SEM__WRITE;
4929                 break;
4930         case IPC_RMID:
4931                 perms = SEM__DESTROY;
4932                 break;
4933         case IPC_SET:
4934                 perms = SEM__SETATTR;
4935                 break;
4936         case IPC_STAT:
4937         case SEM_STAT:
4938                 perms = SEM__GETATTR | SEM__ASSOCIATE;
4939                 break;
4940         default:
4941                 return 0;
4942         }
4943
4944         err = ipc_has_perm(&sma->sem_perm, perms);
4945         return err;
4946 }
4947
4948 static int selinux_sem_semop(struct sem_array *sma,
4949                              struct sembuf *sops, unsigned nsops, int alter)
4950 {
4951         u32 perms;
4952
4953         if (alter)
4954                 perms = SEM__READ | SEM__WRITE;
4955         else
4956                 perms = SEM__READ;
4957
4958         return ipc_has_perm(&sma->sem_perm, perms);
4959 }
4960
4961 static int selinux_ipc_permission(struct kern_ipc_perm *ipcp, short flag)
4962 {
4963         u32 av = 0;
4964
4965         av = 0;
4966         if (flag & S_IRUGO)
4967                 av |= IPC__UNIX_READ;
4968         if (flag & S_IWUGO)
4969                 av |= IPC__UNIX_WRITE;
4970
4971         if (av == 0)
4972                 return 0;
4973
4974         return ipc_has_perm(ipcp, av);
4975 }
4976
4977 /* module stacking operations */
4978 static int selinux_register_security (const char *name, struct security_operations *ops)
4979 {
4980         if (secondary_ops != original_ops) {
4981                 printk(KERN_ERR "%s:  There is already a secondary security "
4982                        "module registered.\n", __FUNCTION__);
4983                 return -EINVAL;
4984         }
4985
4986         secondary_ops = ops;
4987
4988         printk(KERN_INFO "%s:  Registering secondary module %s\n",
4989                __FUNCTION__,
4990                name);
4991
4992         return 0;
4993 }
4994
4995 static void selinux_d_instantiate (struct dentry *dentry, struct inode *inode)
4996 {
4997         if (inode)
4998                 inode_doinit_with_dentry(inode, dentry);
4999 }
5000
5001 static int selinux_getprocattr(struct task_struct *p,
5002                                char *name, char **value)
5003 {
5004         struct task_security_struct *tsec;
5005         u32 sid;
5006         int error;
5007         unsigned len;
5008
5009         if (current != p) {
5010                 error = task_has_perm(current, p, PROCESS__GETATTR);
5011                 if (error)
5012                         return error;
5013         }
5014
5015         tsec = p->security;
5016
5017         if (!strcmp(name, "current"))
5018                 sid = tsec->sid;
5019         else if (!strcmp(name, "prev"))
5020                 sid = tsec->osid;
5021         else if (!strcmp(name, "exec"))
5022                 sid = tsec->exec_sid;
5023         else if (!strcmp(name, "fscreate"))
5024                 sid = tsec->create_sid;
5025         else if (!strcmp(name, "keycreate"))
5026                 sid = tsec->keycreate_sid;
5027         else if (!strcmp(name, "sockcreate"))
5028                 sid = tsec->sockcreate_sid;
5029         else
5030                 return -EINVAL;
5031
5032         if (!sid)
5033                 return 0;
5034
5035         error = security_sid_to_context(sid, value, &len);
5036         if (error)
5037                 return error;
5038         return len;
5039 }
5040
5041 static int selinux_setprocattr(struct task_struct *p,
5042                                char *name, void *value, size_t size)
5043 {
5044         struct task_security_struct *tsec;
5045         u32 sid = 0;
5046         int error;
5047         char *str = value;
5048
5049         if (current != p) {
5050                 /* SELinux only allows a process to change its own
5051                    security attributes. */
5052                 return -EACCES;
5053         }
5054
5055         /*
5056          * Basic control over ability to set these attributes at all.
5057          * current == p, but we'll pass them separately in case the
5058          * above restriction is ever removed.
5059          */
5060         if (!strcmp(name, "exec"))
5061                 error = task_has_perm(current, p, PROCESS__SETEXEC);
5062         else if (!strcmp(name, "fscreate"))
5063                 error = task_has_perm(current, p, PROCESS__SETFSCREATE);
5064         else if (!strcmp(name, "keycreate"))
5065                 error = task_has_perm(current, p, PROCESS__SETKEYCREATE);
5066         else if (!strcmp(name, "sockcreate"))
5067                 error = task_has_perm(current, p, PROCESS__SETSOCKCREATE);
5068         else if (!strcmp(name, "current"))
5069                 error = task_has_perm(current, p, PROCESS__SETCURRENT);
5070         else
5071                 error = -EINVAL;
5072         if (error)
5073                 return error;
5074
5075         /* Obtain a SID for the context, if one was specified. */
5076         if (size && str[1] && str[1] != '\n') {
5077                 if (str[size-1] == '\n') {
5078                         str[size-1] = 0;
5079                         size--;
5080                 }
5081                 error = security_context_to_sid(value, size, &sid);
5082                 if (error)
5083                         return error;
5084         }
5085
5086         /* Permission checking based on the specified context is
5087            performed during the actual operation (execve,
5088            open/mkdir/...), when we know the full context of the
5089            operation.  See selinux_bprm_set_security for the execve
5090            checks and may_create for the file creation checks. The
5091            operation will then fail if the context is not permitted. */
5092         tsec = p->security;
5093         if (!strcmp(name, "exec"))
5094                 tsec->exec_sid = sid;
5095         else if (!strcmp(name, "fscreate"))
5096                 tsec->create_sid = sid;
5097         else if (!strcmp(name, "keycreate")) {
5098                 error = may_create_key(sid, p);
5099                 if (error)
5100                         return error;
5101                 tsec->keycreate_sid = sid;
5102         } else if (!strcmp(name, "sockcreate"))
5103                 tsec->sockcreate_sid = sid;
5104         else if (!strcmp(name, "current")) {
5105                 struct av_decision avd;
5106
5107                 if (sid == 0)
5108                         return -EINVAL;
5109
5110                 /* Only allow single threaded processes to change context */
5111                 if (atomic_read(&p->mm->mm_users) != 1) {
5112                         struct task_struct *g, *t;
5113                         struct mm_struct *mm = p->mm;
5114                         read_lock(&tasklist_lock);
5115                         do_each_thread(g, t)
5116                                 if (t->mm == mm && t != p) {
5117                                         read_unlock(&tasklist_lock);
5118                                         return -EPERM;
5119                                 }
5120                         while_each_thread(g, t);
5121                         read_unlock(&tasklist_lock);
5122                 }
5123
5124                 /* Check permissions for the transition. */
5125                 error = avc_has_perm(tsec->sid, sid, SECCLASS_PROCESS,
5126                                      PROCESS__DYNTRANSITION, NULL);
5127                 if (error)
5128                         return error;
5129
5130                 /* Check for ptracing, and update the task SID if ok.
5131                    Otherwise, leave SID unchanged and fail. */
5132                 task_lock(p);
5133                 if (p->ptrace & PT_PTRACED) {
5134                         error = avc_has_perm_noaudit(tsec->ptrace_sid, sid,
5135                                                      SECCLASS_PROCESS,
5136                                                      PROCESS__PTRACE, 0, &avd);
5137                         if (!error)
5138                                 tsec->sid = sid;
5139                         task_unlock(p);
5140                         avc_audit(tsec->ptrace_sid, sid, SECCLASS_PROCESS,
5141                                   PROCESS__PTRACE, &avd, error, NULL);
5142                         if (error)
5143                                 return error;
5144                 } else {
5145                         tsec->sid = sid;
5146                         task_unlock(p);
5147                 }
5148         }
5149         else
5150                 return -EINVAL;
5151
5152         return size;
5153 }
5154
5155 static int selinux_secid_to_secctx(u32 secid, char **secdata, u32 *seclen)
5156 {
5157         return security_sid_to_context(secid, secdata, seclen);
5158 }
5159
5160 static int selinux_secctx_to_secid(char *secdata, u32 seclen, u32 *secid)
5161 {
5162         return security_context_to_sid(secdata, seclen, secid);
5163 }
5164
5165 static void selinux_release_secctx(char *secdata, u32 seclen)
5166 {
5167         kfree(secdata);
5168 }
5169
5170 #ifdef CONFIG_KEYS
5171
5172 static int selinux_key_alloc(struct key *k, struct task_struct *tsk,
5173                              unsigned long flags)
5174 {
5175         struct task_security_struct *tsec = tsk->security;
5176         struct key_security_struct *ksec;
5177
5178         ksec = kzalloc(sizeof(struct key_security_struct), GFP_KERNEL);
5179         if (!ksec)
5180                 return -ENOMEM;
5181
5182         ksec->obj = k;
5183         if (tsec->keycreate_sid)
5184                 ksec->sid = tsec->keycreate_sid;
5185         else
5186                 ksec->sid = tsec->sid;
5187         k->security = ksec;
5188
5189         return 0;
5190 }
5191
5192 static void selinux_key_free(struct key *k)
5193 {
5194         struct key_security_struct *ksec = k->security;
5195
5196         k->security = NULL;
5197         kfree(ksec);
5198 }
5199
5200 static int selinux_key_permission(key_ref_t key_ref,
5201                             struct task_struct *ctx,
5202                             key_perm_t perm)
5203 {
5204         struct key *key;
5205         struct task_security_struct *tsec;
5206         struct key_security_struct *ksec;
5207
5208         key = key_ref_to_ptr(key_ref);
5209
5210         tsec = ctx->security;
5211         ksec = key->security;
5212
5213         /* if no specific permissions are requested, we skip the
5214            permission check. No serious, additional covert channels
5215            appear to be created. */
5216         if (perm == 0)
5217                 return 0;
5218
5219         return avc_has_perm(tsec->sid, ksec->sid,
5220                             SECCLASS_KEY, perm, NULL);
5221 }
5222
5223 #endif
5224
5225 static struct security_operations selinux_ops = {
5226         .ptrace =                       selinux_ptrace,
5227         .capget =                       selinux_capget,
5228         .capset_check =                 selinux_capset_check,
5229         .capset_set =                   selinux_capset_set,
5230         .sysctl =                       selinux_sysctl,
5231         .capable =                      selinux_capable,
5232         .quotactl =                     selinux_quotactl,
5233         .quota_on =                     selinux_quota_on,
5234         .syslog =                       selinux_syslog,
5235         .vm_enough_memory =             selinux_vm_enough_memory,
5236
5237         .netlink_send =                 selinux_netlink_send,
5238         .netlink_recv =                 selinux_netlink_recv,
5239
5240         .bprm_alloc_security =          selinux_bprm_alloc_security,
5241         .bprm_free_security =           selinux_bprm_free_security,
5242         .bprm_apply_creds =             selinux_bprm_apply_creds,
5243         .bprm_post_apply_creds =        selinux_bprm_post_apply_creds,
5244         .bprm_set_security =            selinux_bprm_set_security,
5245         .bprm_check_security =          selinux_bprm_check_security,
5246         .bprm_secureexec =              selinux_bprm_secureexec,
5247
5248         .sb_alloc_security =            selinux_sb_alloc_security,
5249         .sb_free_security =             selinux_sb_free_security,
5250         .sb_copy_data =                 selinux_sb_copy_data,
5251         .sb_kern_mount =                selinux_sb_kern_mount,
5252         .sb_statfs =                    selinux_sb_statfs,
5253         .sb_mount =                     selinux_mount,
5254         .sb_umount =                    selinux_umount,
5255         .sb_get_mnt_opts =              selinux_get_mnt_opts,
5256         .sb_set_mnt_opts =              selinux_set_mnt_opts,
5257         .sb_clone_mnt_opts =            selinux_sb_clone_mnt_opts,
5258
5259         .inode_alloc_security =         selinux_inode_alloc_security,
5260         .inode_free_security =          selinux_inode_free_security,
5261         .inode_init_security =          selinux_inode_init_security,
5262         .inode_create =                 selinux_inode_create,
5263         .inode_link =                   selinux_inode_link,
5264         .inode_unlink =                 selinux_inode_unlink,
5265         .inode_symlink =                selinux_inode_symlink,
5266         .inode_mkdir =                  selinux_inode_mkdir,
5267         .inode_rmdir =                  selinux_inode_rmdir,
5268         .inode_mknod =                  selinux_inode_mknod,
5269         .inode_rename =                 selinux_inode_rename,
5270         .inode_readlink =               selinux_inode_readlink,
5271         .inode_follow_link =            selinux_inode_follow_link,
5272         .inode_permission =             selinux_inode_permission,
5273         .inode_setattr =                selinux_inode_setattr,
5274         .inode_getattr =                selinux_inode_getattr,
5275         .inode_setxattr =               selinux_inode_setxattr,
5276         .inode_post_setxattr =          selinux_inode_post_setxattr,
5277         .inode_getxattr =               selinux_inode_getxattr,
5278         .inode_listxattr =              selinux_inode_listxattr,
5279         .inode_removexattr =            selinux_inode_removexattr,
5280         .inode_getsecurity =            selinux_inode_getsecurity,
5281         .inode_setsecurity =            selinux_inode_setsecurity,
5282         .inode_listsecurity =           selinux_inode_listsecurity,
5283         .inode_need_killpriv =          selinux_inode_need_killpriv,
5284         .inode_killpriv =               selinux_inode_killpriv,
5285
5286         .file_permission =              selinux_file_permission,
5287         .file_alloc_security =          selinux_file_alloc_security,
5288         .file_free_security =           selinux_file_free_security,
5289         .file_ioctl =                   selinux_file_ioctl,
5290         .file_mmap =                    selinux_file_mmap,
5291         .file_mprotect =                selinux_file_mprotect,
5292         .file_lock =                    selinux_file_lock,
5293         .file_fcntl =                   selinux_file_fcntl,
5294         .file_set_fowner =              selinux_file_set_fowner,
5295         .file_send_sigiotask =          selinux_file_send_sigiotask,
5296         .file_receive =                 selinux_file_receive,
5297
5298         .dentry_open =                  selinux_dentry_open,
5299
5300         .task_create =                  selinux_task_create,
5301         .task_alloc_security =          selinux_task_alloc_security,
5302         .task_free_security =           selinux_task_free_security,
5303         .task_setuid =                  selinux_task_setuid,
5304         .task_post_setuid =             selinux_task_post_setuid,
5305         .task_setgid =                  selinux_task_setgid,
5306         .task_setpgid =                 selinux_task_setpgid,
5307         .task_getpgid =                 selinux_task_getpgid,
5308         .task_getsid =                  selinux_task_getsid,
5309         .task_getsecid =                selinux_task_getsecid,
5310         .task_setgroups =               selinux_task_setgroups,
5311         .task_setnice =                 selinux_task_setnice,
5312         .task_setioprio =               selinux_task_setioprio,
5313         .task_getioprio =               selinux_task_getioprio,
5314         .task_setrlimit =               selinux_task_setrlimit,
5315         .task_setscheduler =            selinux_task_setscheduler,
5316         .task_getscheduler =            selinux_task_getscheduler,
5317         .task_movememory =              selinux_task_movememory,
5318         .task_kill =                    selinux_task_kill,
5319         .task_wait =                    selinux_task_wait,
5320         .task_prctl =                   selinux_task_prctl,
5321         .task_reparent_to_init =        selinux_task_reparent_to_init,
5322         .task_to_inode =                selinux_task_to_inode,
5323
5324         .ipc_permission =               selinux_ipc_permission,
5325
5326         .msg_msg_alloc_security =       selinux_msg_msg_alloc_security,
5327         .msg_msg_free_security =        selinux_msg_msg_free_security,
5328
5329         .msg_queue_alloc_security =     selinux_msg_queue_alloc_security,
5330         .msg_queue_free_security =      selinux_msg_queue_free_security,
5331         .msg_queue_associate =          selinux_msg_queue_associate,
5332         .msg_queue_msgctl =             selinux_msg_queue_msgctl,
5333         .msg_queue_msgsnd =             selinux_msg_queue_msgsnd,
5334         .msg_queue_msgrcv =             selinux_msg_queue_msgrcv,
5335
5336         .shm_alloc_security =           selinux_shm_alloc_security,
5337         .shm_free_security =            selinux_shm_free_security,
5338         .shm_associate =                selinux_shm_associate,
5339         .shm_shmctl =                   selinux_shm_shmctl,
5340         .shm_shmat =                    selinux_shm_shmat,
5341
5342         .sem_alloc_security =           selinux_sem_alloc_security,
5343         .sem_free_security =            selinux_sem_free_security,
5344         .sem_associate =                selinux_sem_associate,
5345         .sem_semctl =                   selinux_sem_semctl,
5346         .sem_semop =                    selinux_sem_semop,
5347
5348         .register_security =            selinux_register_security,
5349
5350         .d_instantiate =                selinux_d_instantiate,
5351
5352         .getprocattr =                  selinux_getprocattr,
5353         .setprocattr =                  selinux_setprocattr,
5354
5355         .secid_to_secctx =              selinux_secid_to_secctx,
5356         .secctx_to_secid =              selinux_secctx_to_secid,
5357         .release_secctx =               selinux_release_secctx,
5358
5359         .unix_stream_connect =          selinux_socket_unix_stream_connect,
5360         .unix_may_send =                selinux_socket_unix_may_send,
5361
5362         .socket_create =                selinux_socket_create,
5363         .socket_post_create =           selinux_socket_post_create,
5364         .socket_bind =                  selinux_socket_bind,
5365         .socket_connect =               selinux_socket_connect,
5366         .socket_listen =                selinux_socket_listen,
5367         .socket_accept =                selinux_socket_accept,
5368         .socket_sendmsg =               selinux_socket_sendmsg,
5369         .socket_recvmsg =               selinux_socket_recvmsg,
5370         .socket_getsockname =           selinux_socket_getsockname,
5371         .socket_getpeername =           selinux_socket_getpeername,
5372         .socket_getsockopt =            selinux_socket_getsockopt,
5373         .socket_setsockopt =            selinux_socket_setsockopt,
5374         .socket_shutdown =              selinux_socket_shutdown,
5375         .socket_sock_rcv_skb =          selinux_socket_sock_rcv_skb,
5376         .socket_getpeersec_stream =     selinux_socket_getpeersec_stream,
5377         .socket_getpeersec_dgram =      selinux_socket_getpeersec_dgram,
5378         .sk_alloc_security =            selinux_sk_alloc_security,
5379         .sk_free_security =             selinux_sk_free_security,
5380         .sk_clone_security =            selinux_sk_clone_security,
5381         .sk_getsecid =                  selinux_sk_getsecid,
5382         .sock_graft =                   selinux_sock_graft,
5383         .inet_conn_request =            selinux_inet_conn_request,
5384         .inet_csk_clone =               selinux_inet_csk_clone,
5385         .inet_conn_established =        selinux_inet_conn_established,
5386         .req_classify_flow =            selinux_req_classify_flow,
5387
5388 #ifdef CONFIG_SECURITY_NETWORK_XFRM
5389         .xfrm_policy_alloc_security =   selinux_xfrm_policy_alloc,
5390         .xfrm_policy_clone_security =   selinux_xfrm_policy_clone,
5391         .xfrm_policy_free_security =    selinux_xfrm_policy_free,
5392         .xfrm_policy_delete_security =  selinux_xfrm_policy_delete,
5393         .xfrm_state_alloc_security =    selinux_xfrm_state_alloc,
5394         .xfrm_state_free_security =     selinux_xfrm_state_free,
5395         .xfrm_state_delete_security =   selinux_xfrm_state_delete,
5396         .xfrm_policy_lookup =           selinux_xfrm_policy_lookup,
5397         .xfrm_state_pol_flow_match =    selinux_xfrm_state_pol_flow_match,
5398         .xfrm_decode_session =          selinux_xfrm_decode_session,
5399 #endif
5400
5401 #ifdef CONFIG_KEYS
5402         .key_alloc =                    selinux_key_alloc,
5403         .key_free =                     selinux_key_free,
5404         .key_permission =               selinux_key_permission,
5405 #endif
5406 };
5407
5408 static __init int selinux_init(void)
5409 {
5410         struct task_security_struct *tsec;
5411
5412         if (!selinux_enabled) {
5413                 printk(KERN_INFO "SELinux:  Disabled at boot.\n");
5414                 return 0;
5415         }
5416
5417         printk(KERN_INFO "SELinux:  Initializing.\n");
5418
5419         /* Set the security state for the initial task. */
5420         if (task_alloc_security(current))
5421                 panic("SELinux:  Failed to initialize initial task.\n");
5422         tsec = current->security;
5423         tsec->osid = tsec->sid = SECINITSID_KERNEL;
5424
5425         sel_inode_cache = kmem_cache_create("selinux_inode_security",
5426                                             sizeof(struct inode_security_struct),
5427                                             0, SLAB_PANIC, NULL);
5428         avc_init();
5429
5430         original_ops = secondary_ops = security_ops;
5431         if (!secondary_ops)
5432                 panic ("SELinux: No initial security operations\n");
5433         if (register_security (&selinux_ops))
5434                 panic("SELinux: Unable to register with kernel.\n");
5435
5436         if (selinux_enforcing) {
5437                 printk(KERN_DEBUG "SELinux:  Starting in enforcing mode\n");
5438         } else {
5439                 printk(KERN_DEBUG "SELinux:  Starting in permissive mode\n");
5440         }
5441
5442 #ifdef CONFIG_KEYS
5443         /* Add security information to initial keyrings */
5444         selinux_key_alloc(&root_user_keyring, current,
5445                           KEY_ALLOC_NOT_IN_QUOTA);
5446         selinux_key_alloc(&root_session_keyring, current,
5447                           KEY_ALLOC_NOT_IN_QUOTA);
5448 #endif
5449
5450         return 0;
5451 }
5452
5453 void selinux_complete_init(void)
5454 {
5455         printk(KERN_DEBUG "SELinux:  Completing initialization.\n");
5456
5457         /* Set up any superblocks initialized prior to the policy load. */
5458         printk(KERN_DEBUG "SELinux:  Setting up existing superblocks.\n");
5459         spin_lock(&sb_lock);
5460         spin_lock(&sb_security_lock);
5461 next_sb:
5462         if (!list_empty(&superblock_security_head)) {
5463                 struct superblock_security_struct *sbsec =
5464                                 list_entry(superblock_security_head.next,
5465                                            struct superblock_security_struct,
5466                                            list);
5467                 struct super_block *sb = sbsec->sb;
5468                 sb->s_count++;
5469                 spin_unlock(&sb_security_lock);
5470                 spin_unlock(&sb_lock);
5471                 down_read(&sb->s_umount);
5472                 if (sb->s_root)
5473                         superblock_doinit(sb, NULL);
5474                 drop_super(sb);
5475                 spin_lock(&sb_lock);
5476                 spin_lock(&sb_security_lock);
5477                 list_del_init(&sbsec->list);
5478                 goto next_sb;
5479         }
5480         spin_unlock(&sb_security_lock);
5481         spin_unlock(&sb_lock);
5482 }
5483
5484 /* SELinux requires early initialization in order to label
5485    all processes and objects when they are created. */
5486 security_initcall(selinux_init);
5487
5488 #if defined(CONFIG_NETFILTER)
5489
5490 static struct nf_hook_ops selinux_ipv4_ops[] = {
5491         {
5492                 .hook =         selinux_ipv4_postroute,
5493                 .owner =        THIS_MODULE,
5494                 .pf =           PF_INET,
5495                 .hooknum =      NF_INET_POST_ROUTING,
5496                 .priority =     NF_IP_PRI_SELINUX_LAST,
5497         },
5498         {
5499                 .hook =         selinux_ipv4_forward,
5500                 .owner =        THIS_MODULE,
5501                 .pf =           PF_INET,
5502                 .hooknum =      NF_INET_FORWARD,
5503                 .priority =     NF_IP_PRI_SELINUX_FIRST,
5504         }
5505 };
5506
5507 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
5508
5509 static struct nf_hook_ops selinux_ipv6_ops[] = {
5510         {
5511                 .hook =         selinux_ipv6_postroute,
5512                 .owner =        THIS_MODULE,
5513                 .pf =           PF_INET6,
5514                 .hooknum =      NF_INET_POST_ROUTING,
5515                 .priority =     NF_IP6_PRI_SELINUX_LAST,
5516         },
5517         {
5518                 .hook =         selinux_ipv6_forward,
5519                 .owner =        THIS_MODULE,
5520                 .pf =           PF_INET6,
5521                 .hooknum =      NF_INET_FORWARD,
5522                 .priority =     NF_IP6_PRI_SELINUX_FIRST,
5523         }
5524 };
5525
5526 #endif  /* IPV6 */
5527
5528 static int __init selinux_nf_ip_init(void)
5529 {
5530         int err = 0;
5531         u32 iter;
5532
5533         if (!selinux_enabled)
5534                 goto out;
5535
5536         printk(KERN_DEBUG "SELinux:  Registering netfilter hooks\n");
5537
5538         for (iter = 0; iter < ARRAY_SIZE(selinux_ipv4_ops); iter++) {
5539                 err = nf_register_hook(&selinux_ipv4_ops[iter]);
5540                 if (err)
5541                         panic("SELinux: nf_register_hook for IPv4: error %d\n",
5542                               err);
5543         }
5544
5545 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
5546         for (iter = 0; iter < ARRAY_SIZE(selinux_ipv6_ops); iter++) {
5547                 err = nf_register_hook(&selinux_ipv6_ops[iter]);
5548                 if (err)
5549                         panic("SELinux: nf_register_hook for IPv6: error %d\n",
5550                               err);
5551         }
5552 #endif  /* IPV6 */
5553
5554 out:
5555         return err;
5556 }
5557
5558 __initcall(selinux_nf_ip_init);
5559
5560 #ifdef CONFIG_SECURITY_SELINUX_DISABLE
5561 static void selinux_nf_ip_exit(void)
5562 {
5563         u32 iter;
5564
5565         printk(KERN_DEBUG "SELinux:  Unregistering netfilter hooks\n");
5566
5567         for (iter = 0; iter < ARRAY_SIZE(selinux_ipv4_ops); iter++)
5568                 nf_unregister_hook(&selinux_ipv4_ops[iter]);
5569 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
5570         for (iter = 0; iter < ARRAY_SIZE(selinux_ipv6_ops); iter++)
5571                 nf_unregister_hook(&selinux_ipv6_ops[iter]);
5572 #endif  /* IPV6 */
5573 }
5574 #endif
5575
5576 #else /* CONFIG_NETFILTER */
5577
5578 #ifdef CONFIG_SECURITY_SELINUX_DISABLE
5579 #define selinux_nf_ip_exit()
5580 #endif
5581
5582 #endif /* CONFIG_NETFILTER */
5583
5584 #ifdef CONFIG_SECURITY_SELINUX_DISABLE
5585 int selinux_disable(void)
5586 {
5587         extern void exit_sel_fs(void);
5588         static int selinux_disabled = 0;
5589
5590         if (ss_initialized) {
5591                 /* Not permitted after initial policy load. */
5592                 return -EINVAL;
5593         }
5594
5595         if (selinux_disabled) {
5596                 /* Only do this once. */
5597                 return -EINVAL;
5598         }
5599
5600         printk(KERN_INFO "SELinux:  Disabled at runtime.\n");
5601
5602         selinux_disabled = 1;
5603         selinux_enabled = 0;
5604
5605         /* Reset security_ops to the secondary module, dummy or capability. */
5606         security_ops = secondary_ops;
5607
5608         /* Unregister netfilter hooks. */
5609         selinux_nf_ip_exit();
5610
5611         /* Unregister selinuxfs. */
5612         exit_sel_fs();
5613
5614         return 0;
5615 }
5616 #endif
5617
5618