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