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 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 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         return ret;
3447 }
3448
3449 /**
3450  * selinux_skb_peerlbl_sid - Determine the peer label of a packet
3451  * @skb: the packet
3452  * @family: protocol family
3453  * @sid: the packet's peer label SID
3454  *
3455  * Description:
3456  * Check the various different forms of network peer labeling and determine
3457  * the peer label/SID for the packet; most of the magic actually occurs in
3458  * the security server function security_net_peersid_cmp().  The function
3459  * returns zero if the value in @sid is valid (although it may be SECSID_NULL)
3460  * or -EACCES if @sid is invalid due to inconsistencies with the different
3461  * peer labels.
3462  *
3463  */
3464 static int selinux_skb_peerlbl_sid(struct sk_buff *skb, u16 family, u32 *sid)
3465 {
3466         u32 xfrm_sid;
3467         u32 nlbl_sid;
3468         u32 nlbl_type;
3469
3470         selinux_skb_xfrm_sid(skb, &xfrm_sid);
3471         selinux_netlbl_skbuff_getsid(skb, family, &nlbl_type, &nlbl_sid);
3472
3473         if (security_net_peersid_resolve(nlbl_sid, nlbl_type,
3474                                          xfrm_sid,
3475                                          sid) != 0)
3476                 return -EACCES;
3477
3478         return 0;
3479 }
3480
3481 /* socket security operations */
3482 static int socket_has_perm(struct task_struct *task, struct socket *sock,
3483                            u32 perms)
3484 {
3485         struct inode_security_struct *isec;
3486         struct task_security_struct *tsec;
3487         struct avc_audit_data ad;
3488         int err = 0;
3489
3490         tsec = task->security;
3491         isec = SOCK_INODE(sock)->i_security;
3492
3493         if (isec->sid == SECINITSID_KERNEL)
3494                 goto out;
3495
3496         AVC_AUDIT_DATA_INIT(&ad,NET);
3497         ad.u.net.sk = sock->sk;
3498         err = avc_has_perm(tsec->sid, isec->sid, isec->sclass, perms, &ad);
3499
3500 out:
3501         return err;
3502 }
3503
3504 static int selinux_socket_create(int family, int type,
3505                                  int protocol, int kern)
3506 {
3507         int err = 0;
3508         struct task_security_struct *tsec;
3509         u32 newsid;
3510
3511         if (kern)
3512                 goto out;
3513
3514         tsec = current->security;
3515         newsid = tsec->sockcreate_sid ? : tsec->sid;
3516         err = avc_has_perm(tsec->sid, newsid,
3517                            socket_type_to_security_class(family, type,
3518                            protocol), SOCKET__CREATE, NULL);
3519
3520 out:
3521         return err;
3522 }
3523
3524 static int selinux_socket_post_create(struct socket *sock, int family,
3525                                       int type, int protocol, int kern)
3526 {
3527         int err = 0;
3528         struct inode_security_struct *isec;
3529         struct task_security_struct *tsec;
3530         struct sk_security_struct *sksec;
3531         u32 newsid;
3532
3533         isec = SOCK_INODE(sock)->i_security;
3534
3535         tsec = current->security;
3536         newsid = tsec->sockcreate_sid ? : tsec->sid;
3537         isec->sclass = socket_type_to_security_class(family, type, protocol);
3538         isec->sid = kern ? SECINITSID_KERNEL : newsid;
3539         isec->initialized = 1;
3540
3541         if (sock->sk) {
3542                 sksec = sock->sk->sk_security;
3543                 sksec->sid = isec->sid;
3544                 sksec->sclass = isec->sclass;
3545                 err = selinux_netlbl_socket_post_create(sock);
3546         }
3547
3548         return err;
3549 }
3550
3551 /* Range of port numbers used to automatically bind.
3552    Need to determine whether we should perform a name_bind
3553    permission check between the socket and the port number. */
3554
3555 static int selinux_socket_bind(struct socket *sock, struct sockaddr *address, int addrlen)
3556 {
3557         u16 family;
3558         int err;
3559
3560         err = socket_has_perm(current, sock, SOCKET__BIND);
3561         if (err)
3562                 goto out;
3563
3564         /*
3565          * If PF_INET or PF_INET6, check name_bind permission for the port.
3566          * Multiple address binding for SCTP is not supported yet: we just
3567          * check the first address now.
3568          */
3569         family = sock->sk->sk_family;
3570         if (family == PF_INET || family == PF_INET6) {
3571                 char *addrp;
3572                 struct inode_security_struct *isec;
3573                 struct task_security_struct *tsec;
3574                 struct avc_audit_data ad;
3575                 struct sockaddr_in *addr4 = NULL;
3576                 struct sockaddr_in6 *addr6 = NULL;
3577                 unsigned short snum;
3578                 struct sock *sk = sock->sk;
3579                 u32 sid, node_perm, addrlen;
3580
3581                 tsec = current->security;
3582                 isec = SOCK_INODE(sock)->i_security;
3583
3584                 if (family == PF_INET) {
3585                         addr4 = (struct sockaddr_in *)address;
3586                         snum = ntohs(addr4->sin_port);
3587                         addrlen = sizeof(addr4->sin_addr.s_addr);
3588                         addrp = (char *)&addr4->sin_addr.s_addr;
3589                 } else {
3590                         addr6 = (struct sockaddr_in6 *)address;
3591                         snum = ntohs(addr6->sin6_port);
3592                         addrlen = sizeof(addr6->sin6_addr.s6_addr);
3593                         addrp = (char *)&addr6->sin6_addr.s6_addr;
3594                 }
3595
3596                 if (snum) {
3597                         int low, high;
3598
3599                         inet_get_local_port_range(&low, &high);
3600
3601                         if (snum < max(PROT_SOCK, low) || snum > high) {
3602                                 err = security_port_sid(sk->sk_family,
3603                                                         sk->sk_type,
3604                                                         sk->sk_protocol, snum,
3605                                                         &sid);
3606                                 if (err)
3607                                         goto out;
3608                                 AVC_AUDIT_DATA_INIT(&ad,NET);
3609                                 ad.u.net.sport = htons(snum);
3610                                 ad.u.net.family = family;
3611                                 err = avc_has_perm(isec->sid, sid,
3612                                                    isec->sclass,
3613                                                    SOCKET__NAME_BIND, &ad);
3614                                 if (err)
3615                                         goto out;
3616                         }
3617                 }
3618
3619                 switch(isec->sclass) {
3620                 case SECCLASS_TCP_SOCKET:
3621                         node_perm = TCP_SOCKET__NODE_BIND;
3622                         break;
3623
3624                 case SECCLASS_UDP_SOCKET:
3625                         node_perm = UDP_SOCKET__NODE_BIND;
3626                         break;
3627
3628                 case SECCLASS_DCCP_SOCKET:
3629                         node_perm = DCCP_SOCKET__NODE_BIND;
3630                         break;
3631
3632                 default:
3633                         node_perm = RAWIP_SOCKET__NODE_BIND;
3634                         break;
3635                 }
3636
3637                 err = sel_netnode_sid(addrp, family, &sid);
3638                 if (err)
3639                         goto out;
3640
3641                 AVC_AUDIT_DATA_INIT(&ad,NET);
3642                 ad.u.net.sport = htons(snum);
3643                 ad.u.net.family = family;
3644
3645                 if (family == PF_INET)
3646                         ad.u.net.v4info.saddr = addr4->sin_addr.s_addr;
3647                 else
3648                         ipv6_addr_copy(&ad.u.net.v6info.saddr, &addr6->sin6_addr);
3649
3650                 err = avc_has_perm(isec->sid, sid,
3651                                    isec->sclass, node_perm, &ad);
3652                 if (err)
3653                         goto out;
3654         }
3655 out:
3656         return err;
3657 }
3658
3659 static int selinux_socket_connect(struct socket *sock, struct sockaddr *address, int addrlen)
3660 {
3661         struct inode_security_struct *isec;
3662         int err;
3663
3664         err = socket_has_perm(current, sock, SOCKET__CONNECT);
3665         if (err)
3666                 return err;
3667
3668         /*
3669          * If a TCP or DCCP socket, check name_connect permission for the port.
3670          */
3671         isec = SOCK_INODE(sock)->i_security;
3672         if (isec->sclass == SECCLASS_TCP_SOCKET ||
3673             isec->sclass == SECCLASS_DCCP_SOCKET) {
3674                 struct sock *sk = sock->sk;
3675                 struct avc_audit_data ad;
3676                 struct sockaddr_in *addr4 = NULL;
3677                 struct sockaddr_in6 *addr6 = NULL;
3678                 unsigned short snum;
3679                 u32 sid, perm;
3680
3681                 if (sk->sk_family == PF_INET) {
3682                         addr4 = (struct sockaddr_in *)address;
3683                         if (addrlen < sizeof(struct sockaddr_in))
3684                                 return -EINVAL;
3685                         snum = ntohs(addr4->sin_port);
3686                 } else {
3687                         addr6 = (struct sockaddr_in6 *)address;
3688                         if (addrlen < SIN6_LEN_RFC2133)
3689                                 return -EINVAL;
3690                         snum = ntohs(addr6->sin6_port);
3691                 }
3692
3693                 err = security_port_sid(sk->sk_family, sk->sk_type,
3694                                         sk->sk_protocol, snum, &sid);
3695                 if (err)
3696                         goto out;
3697
3698                 perm = (isec->sclass == SECCLASS_TCP_SOCKET) ?
3699                        TCP_SOCKET__NAME_CONNECT : DCCP_SOCKET__NAME_CONNECT;
3700
3701                 AVC_AUDIT_DATA_INIT(&ad,NET);
3702                 ad.u.net.dport = htons(snum);
3703                 ad.u.net.family = sk->sk_family;
3704                 err = avc_has_perm(isec->sid, sid, isec->sclass, perm, &ad);
3705                 if (err)
3706                         goto out;
3707         }
3708
3709 out:
3710         return err;
3711 }
3712
3713 static int selinux_socket_listen(struct socket *sock, int backlog)
3714 {
3715         return socket_has_perm(current, sock, SOCKET__LISTEN);
3716 }
3717
3718 static int selinux_socket_accept(struct socket *sock, struct socket *newsock)
3719 {
3720         int err;
3721         struct inode_security_struct *isec;
3722         struct inode_security_struct *newisec;
3723
3724         err = socket_has_perm(current, sock, SOCKET__ACCEPT);
3725         if (err)
3726                 return err;
3727
3728         newisec = SOCK_INODE(newsock)->i_security;
3729
3730         isec = SOCK_INODE(sock)->i_security;
3731         newisec->sclass = isec->sclass;
3732         newisec->sid = isec->sid;
3733         newisec->initialized = 1;
3734
3735         return 0;
3736 }
3737
3738 static int selinux_socket_sendmsg(struct socket *sock, struct msghdr *msg,
3739                                   int size)
3740 {
3741         int rc;
3742
3743         rc = socket_has_perm(current, sock, SOCKET__WRITE);
3744         if (rc)
3745                 return rc;
3746
3747         return selinux_netlbl_inode_permission(SOCK_INODE(sock), MAY_WRITE);
3748 }
3749
3750 static int selinux_socket_recvmsg(struct socket *sock, struct msghdr *msg,
3751                                   int size, int flags)
3752 {
3753         return socket_has_perm(current, sock, SOCKET__READ);
3754 }
3755
3756 static int selinux_socket_getsockname(struct socket *sock)
3757 {
3758         return socket_has_perm(current, sock, SOCKET__GETATTR);
3759 }
3760
3761 static int selinux_socket_getpeername(struct socket *sock)
3762 {
3763         return socket_has_perm(current, sock, SOCKET__GETATTR);
3764 }
3765
3766 static int selinux_socket_setsockopt(struct socket *sock,int level,int optname)
3767 {
3768         int err;
3769
3770         err = socket_has_perm(current, sock, SOCKET__SETOPT);
3771         if (err)
3772                 return err;
3773
3774         return selinux_netlbl_socket_setsockopt(sock, level, optname);
3775 }
3776
3777 static int selinux_socket_getsockopt(struct socket *sock, int level,
3778                                      int optname)
3779 {
3780         return socket_has_perm(current, sock, SOCKET__GETOPT);
3781 }
3782
3783 static int selinux_socket_shutdown(struct socket *sock, int how)
3784 {
3785         return socket_has_perm(current, sock, SOCKET__SHUTDOWN);
3786 }
3787
3788 static int selinux_socket_unix_stream_connect(struct socket *sock,
3789                                               struct socket *other,
3790                                               struct sock *newsk)
3791 {
3792         struct sk_security_struct *ssec;
3793         struct inode_security_struct *isec;
3794         struct inode_security_struct *other_isec;
3795         struct avc_audit_data ad;
3796         int err;
3797
3798         err = secondary_ops->unix_stream_connect(sock, other, newsk);
3799         if (err)
3800                 return err;
3801
3802         isec = SOCK_INODE(sock)->i_security;
3803         other_isec = SOCK_INODE(other)->i_security;
3804
3805         AVC_AUDIT_DATA_INIT(&ad,NET);
3806         ad.u.net.sk = other->sk;
3807
3808         err = avc_has_perm(isec->sid, other_isec->sid,
3809                            isec->sclass,
3810                            UNIX_STREAM_SOCKET__CONNECTTO, &ad);
3811         if (err)
3812                 return err;
3813
3814         /* connecting socket */
3815         ssec = sock->sk->sk_security;
3816         ssec->peer_sid = other_isec->sid;
3817
3818         /* server child socket */
3819         ssec = newsk->sk_security;
3820         ssec->peer_sid = isec->sid;
3821         err = security_sid_mls_copy(other_isec->sid, ssec->peer_sid, &ssec->sid);
3822
3823         return err;
3824 }
3825
3826 static int selinux_socket_unix_may_send(struct socket *sock,
3827                                         struct socket *other)
3828 {
3829         struct inode_security_struct *isec;
3830         struct inode_security_struct *other_isec;
3831         struct avc_audit_data ad;
3832         int err;
3833
3834         isec = SOCK_INODE(sock)->i_security;
3835         other_isec = SOCK_INODE(other)->i_security;
3836
3837         AVC_AUDIT_DATA_INIT(&ad,NET);
3838         ad.u.net.sk = other->sk;
3839
3840         err = avc_has_perm(isec->sid, other_isec->sid,
3841                            isec->sclass, SOCKET__SENDTO, &ad);
3842         if (err)
3843                 return err;
3844
3845         return 0;
3846 }
3847
3848 static int selinux_sock_rcv_skb_iptables_compat(struct sock *sk,
3849                                                 struct sk_buff *skb,
3850                                                 struct avc_audit_data *ad,
3851                                                 u16 family,
3852                                                 char *addrp)
3853 {
3854         int err;
3855         struct sk_security_struct *sksec = sk->sk_security;
3856         u16 sk_class;
3857         u32 netif_perm, node_perm, recv_perm;
3858         u32 port_sid, node_sid, if_sid, sk_sid;
3859
3860         sk_sid = sksec->sid;
3861         sk_class = sksec->sclass;
3862
3863         switch (sk_class) {
3864         case SECCLASS_UDP_SOCKET:
3865                 netif_perm = NETIF__UDP_RECV;
3866                 node_perm = NODE__UDP_RECV;
3867                 recv_perm = UDP_SOCKET__RECV_MSG;
3868                 break;
3869         case SECCLASS_TCP_SOCKET:
3870                 netif_perm = NETIF__TCP_RECV;
3871                 node_perm = NODE__TCP_RECV;
3872                 recv_perm = TCP_SOCKET__RECV_MSG;
3873                 break;
3874         case SECCLASS_DCCP_SOCKET:
3875                 netif_perm = NETIF__DCCP_RECV;
3876                 node_perm = NODE__DCCP_RECV;
3877                 recv_perm = DCCP_SOCKET__RECV_MSG;
3878                 break;
3879         default:
3880                 netif_perm = NETIF__RAWIP_RECV;
3881                 node_perm = NODE__RAWIP_RECV;
3882                 recv_perm = 0;
3883                 break;
3884         }
3885
3886         err = sel_netif_sid(skb->iif, &if_sid);
3887         if (err)
3888                 return err;
3889         err = avc_has_perm(sk_sid, if_sid, SECCLASS_NETIF, netif_perm, ad);
3890         if (err)
3891                 return err;
3892
3893         err = sel_netnode_sid(addrp, family, &node_sid);
3894         if (err)
3895                 return err;
3896         err = avc_has_perm(sk_sid, node_sid, SECCLASS_NODE, node_perm, ad);
3897         if (err)
3898                 return err;
3899
3900         if (!recv_perm)
3901                 return 0;
3902         err = security_port_sid(sk->sk_family, sk->sk_type,
3903                                 sk->sk_protocol, ntohs(ad->u.net.sport),
3904                                 &port_sid);
3905         if (err)
3906                 return err;
3907         return avc_has_perm(sk_sid, port_sid, sk_class, recv_perm, ad);
3908 }
3909
3910 static int selinux_sock_rcv_skb_compat(struct sock *sk, struct sk_buff *skb,
3911                                        struct avc_audit_data *ad,
3912                                        u16 family, char *addrp)
3913 {
3914         int err;
3915         struct sk_security_struct *sksec = sk->sk_security;
3916         u32 peer_sid;
3917         u32 sk_sid = sksec->sid;
3918
3919         if (selinux_compat_net)
3920                 err = selinux_sock_rcv_skb_iptables_compat(sk, skb, ad,
3921                                                            family, addrp);
3922         else
3923                 err = avc_has_perm(sk_sid, skb->secmark, SECCLASS_PACKET,
3924                                    PACKET__RECV, ad);
3925         if (err)
3926                 return err;
3927
3928         if (selinux_policycap_netpeer) {
3929                 err = selinux_skb_peerlbl_sid(skb, family, &peer_sid);
3930                 if (err)
3931                         return err;
3932                 err = avc_has_perm(sk_sid, peer_sid,
3933                                    SECCLASS_PEER, PEER__RECV, ad);
3934         } else {
3935                 err = selinux_netlbl_sock_rcv_skb(sksec, skb, family, ad);
3936                 if (err)
3937                         return err;
3938                 err = selinux_xfrm_sock_rcv_skb(sksec->sid, skb, ad);
3939         }
3940
3941         return err;
3942 }
3943
3944 static int selinux_socket_sock_rcv_skb(struct sock *sk, struct sk_buff *skb)
3945 {
3946         int err;
3947         struct sk_security_struct *sksec = sk->sk_security;
3948         u16 family = sk->sk_family;
3949         u32 sk_sid = sksec->sid;
3950         struct avc_audit_data ad;
3951         char *addrp;
3952
3953         if (family != PF_INET && family != PF_INET6)
3954                 return 0;
3955
3956         /* Handle mapped IPv4 packets arriving via IPv6 sockets */
3957         if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
3958                 family = PF_INET;
3959
3960         AVC_AUDIT_DATA_INIT(&ad, NET);
3961         ad.u.net.netif = skb->iif;
3962         ad.u.net.family = family;
3963         err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL);
3964         if (err)
3965                 return err;
3966
3967         /* If any sort of compatibility mode is enabled then handoff processing
3968          * to the selinux_sock_rcv_skb_compat() function to deal with the
3969          * special handling.  We do this in an attempt to keep this function
3970          * as fast and as clean as possible. */
3971         if (selinux_compat_net || !selinux_policycap_netpeer)
3972                 return selinux_sock_rcv_skb_compat(sk, skb, &ad,
3973                                                    family, addrp);
3974
3975         if (selinux_secmark_enabled()) {
3976                 err = avc_has_perm(sk_sid, skb->secmark, SECCLASS_PACKET,
3977                                    PACKET__RECV, &ad);
3978                 if (err)
3979                         return err;
3980         }
3981
3982         if (netlbl_enabled() || selinux_xfrm_enabled()) {
3983                 u32 peer_sid;
3984
3985                 err = selinux_skb_peerlbl_sid(skb, family, &peer_sid);
3986                 if (err)
3987                         return err;
3988                 err = avc_has_perm(sk_sid, peer_sid, SECCLASS_PEER,
3989                                    PEER__RECV, &ad);
3990         }
3991
3992         return err;
3993 }
3994
3995 static int selinux_socket_getpeersec_stream(struct socket *sock, char __user *optval,
3996                                             int __user *optlen, unsigned len)
3997 {
3998         int err = 0;
3999         char *scontext;
4000         u32 scontext_len;
4001         struct sk_security_struct *ssec;
4002         struct inode_security_struct *isec;
4003         u32 peer_sid = SECSID_NULL;
4004
4005         isec = SOCK_INODE(sock)->i_security;
4006
4007         if (isec->sclass == SECCLASS_UNIX_STREAM_SOCKET ||
4008             isec->sclass == SECCLASS_TCP_SOCKET) {
4009                 ssec = sock->sk->sk_security;
4010                 peer_sid = ssec->peer_sid;
4011         }
4012         if (peer_sid == SECSID_NULL) {
4013                 err = -ENOPROTOOPT;
4014                 goto out;
4015         }
4016
4017         err = security_sid_to_context(peer_sid, &scontext, &scontext_len);
4018
4019         if (err)
4020                 goto out;
4021
4022         if (scontext_len > len) {
4023                 err = -ERANGE;
4024                 goto out_len;
4025         }
4026
4027         if (copy_to_user(optval, scontext, scontext_len))
4028                 err = -EFAULT;
4029
4030 out_len:
4031         if (put_user(scontext_len, optlen))
4032                 err = -EFAULT;
4033
4034         kfree(scontext);
4035 out:
4036         return err;
4037 }
4038
4039 static int selinux_socket_getpeersec_dgram(struct socket *sock, struct sk_buff *skb, u32 *secid)
4040 {
4041         u32 peer_secid = SECSID_NULL;
4042         u16 family;
4043
4044         if (sock)
4045                 family = sock->sk->sk_family;
4046         else if (skb && skb->sk)
4047                 family = skb->sk->sk_family;
4048         else
4049                 goto out;
4050
4051         if (sock && family == PF_UNIX)
4052                 selinux_get_inode_sid(SOCK_INODE(sock), &peer_secid);
4053         else if (skb)
4054                 selinux_skb_peerlbl_sid(skb, family, &peer_secid);
4055
4056 out:
4057         *secid = peer_secid;
4058         if (peer_secid == SECSID_NULL)
4059                 return -EINVAL;
4060         return 0;
4061 }
4062
4063 static int selinux_sk_alloc_security(struct sock *sk, int family, gfp_t priority)
4064 {
4065         return sk_alloc_security(sk, family, priority);
4066 }
4067
4068 static void selinux_sk_free_security(struct sock *sk)
4069 {
4070         sk_free_security(sk);
4071 }
4072
4073 static void selinux_sk_clone_security(const struct sock *sk, struct sock *newsk)
4074 {
4075         struct sk_security_struct *ssec = sk->sk_security;
4076         struct sk_security_struct *newssec = newsk->sk_security;
4077
4078         newssec->sid = ssec->sid;
4079         newssec->peer_sid = ssec->peer_sid;
4080         newssec->sclass = ssec->sclass;
4081
4082         selinux_netlbl_sk_security_clone(ssec, newssec);
4083 }
4084
4085 static void selinux_sk_getsecid(struct sock *sk, u32 *secid)
4086 {
4087         if (!sk)
4088                 *secid = SECINITSID_ANY_SOCKET;
4089         else {
4090                 struct sk_security_struct *sksec = sk->sk_security;
4091
4092                 *secid = sksec->sid;
4093         }
4094 }
4095
4096 static void selinux_sock_graft(struct sock* sk, struct socket *parent)
4097 {
4098         struct inode_security_struct *isec = SOCK_INODE(parent)->i_security;
4099         struct sk_security_struct *sksec = sk->sk_security;
4100
4101         if (sk->sk_family == PF_INET || sk->sk_family == PF_INET6 ||
4102             sk->sk_family == PF_UNIX)
4103                 isec->sid = sksec->sid;
4104         sksec->sclass = isec->sclass;
4105
4106         selinux_netlbl_sock_graft(sk, parent);
4107 }
4108
4109 static int selinux_inet_conn_request(struct sock *sk, struct sk_buff *skb,
4110                                      struct request_sock *req)
4111 {
4112         struct sk_security_struct *sksec = sk->sk_security;
4113         int err;
4114         u32 newsid;
4115         u32 peersid;
4116
4117         err = selinux_skb_peerlbl_sid(skb, sk->sk_family, &peersid);
4118         if (err)
4119                 return err;
4120         if (peersid == SECSID_NULL) {
4121                 req->secid = sksec->sid;
4122                 req->peer_secid = SECSID_NULL;
4123                 return 0;
4124         }
4125
4126         err = security_sid_mls_copy(sksec->sid, peersid, &newsid);
4127         if (err)
4128                 return err;
4129
4130         req->secid = newsid;
4131         req->peer_secid = peersid;
4132         return 0;
4133 }
4134
4135 static void selinux_inet_csk_clone(struct sock *newsk,
4136                                    const struct request_sock *req)
4137 {
4138         struct sk_security_struct *newsksec = newsk->sk_security;
4139
4140         newsksec->sid = req->secid;
4141         newsksec->peer_sid = req->peer_secid;
4142         /* NOTE: Ideally, we should also get the isec->sid for the
4143            new socket in sync, but we don't have the isec available yet.
4144            So we will wait until sock_graft to do it, by which
4145            time it will have been created and available. */
4146
4147         /* We don't need to take any sort of lock here as we are the only
4148          * thread with access to newsksec */
4149         selinux_netlbl_sk_security_reset(newsksec, req->rsk_ops->family);
4150 }
4151
4152 static void selinux_inet_conn_established(struct sock *sk,
4153                                 struct sk_buff *skb)
4154 {
4155         struct sk_security_struct *sksec = sk->sk_security;
4156
4157         selinux_skb_peerlbl_sid(skb, sk->sk_family, &sksec->peer_sid);
4158 }
4159
4160 static void selinux_req_classify_flow(const struct request_sock *req,
4161                                       struct flowi *fl)
4162 {
4163         fl->secid = req->secid;
4164 }
4165
4166 static int selinux_nlmsg_perm(struct sock *sk, struct sk_buff *skb)
4167 {
4168         int err = 0;
4169         u32 perm;
4170         struct nlmsghdr *nlh;
4171         struct socket *sock = sk->sk_socket;
4172         struct inode_security_struct *isec = SOCK_INODE(sock)->i_security;
4173
4174         if (skb->len < NLMSG_SPACE(0)) {
4175                 err = -EINVAL;
4176                 goto out;
4177         }
4178         nlh = nlmsg_hdr(skb);
4179
4180         err = selinux_nlmsg_lookup(isec->sclass, nlh->nlmsg_type, &perm);
4181         if (err) {
4182                 if (err == -EINVAL) {
4183                         audit_log(current->audit_context, GFP_KERNEL, AUDIT_SELINUX_ERR,
4184                                   "SELinux:  unrecognized netlink message"
4185                                   " type=%hu for sclass=%hu\n",
4186                                   nlh->nlmsg_type, isec->sclass);
4187                         if (!selinux_enforcing)
4188                                 err = 0;
4189                 }
4190
4191                 /* Ignore */
4192                 if (err == -ENOENT)
4193                         err = 0;
4194                 goto out;
4195         }
4196
4197         err = socket_has_perm(current, sock, perm);
4198 out:
4199         return err;
4200 }
4201
4202 #ifdef CONFIG_NETFILTER
4203
4204 static int selinux_ip_postroute_last_compat(struct sock *sk,
4205                                             struct net_device *dev,
4206                                             struct avc_audit_data *ad,
4207                                             u16 family,
4208                                             char *addrp)
4209 {
4210         int err = 0;
4211         u32 netif_perm, node_perm, node_sid, if_sid, send_perm = 0;
4212         struct socket *sock;
4213         struct inode *inode;
4214         struct inode_security_struct *isec;
4215
4216         sock = sk->sk_socket;
4217         if (!sock)
4218                 goto out;
4219
4220         inode = SOCK_INODE(sock);
4221         if (!inode)
4222                 goto out;
4223
4224         isec = inode->i_security;
4225
4226         err = sel_netif_sid(dev->ifindex, &if_sid);
4227         if (err)
4228                 goto out;
4229
4230         switch (isec->sclass) {
4231         case SECCLASS_UDP_SOCKET:
4232                 netif_perm = NETIF__UDP_SEND;
4233                 node_perm = NODE__UDP_SEND;
4234                 send_perm = UDP_SOCKET__SEND_MSG;
4235                 break;
4236
4237         case SECCLASS_TCP_SOCKET:
4238                 netif_perm = NETIF__TCP_SEND;
4239                 node_perm = NODE__TCP_SEND;
4240                 send_perm = TCP_SOCKET__SEND_MSG;
4241                 break;
4242
4243         case SECCLASS_DCCP_SOCKET:
4244                 netif_perm = NETIF__DCCP_SEND;
4245                 node_perm = NODE__DCCP_SEND;
4246                 send_perm = DCCP_SOCKET__SEND_MSG;
4247                 break;
4248
4249         default:
4250                 netif_perm = NETIF__RAWIP_SEND;
4251                 node_perm = NODE__RAWIP_SEND;
4252                 break;
4253         }
4254
4255         err = avc_has_perm(isec->sid, if_sid, SECCLASS_NETIF, netif_perm, ad);
4256         if (err)
4257                 goto out;
4258
4259         err = sel_netnode_sid(addrp, family, &node_sid);
4260         if (err)
4261                 goto out;
4262
4263         err = avc_has_perm(isec->sid, node_sid, SECCLASS_NODE, node_perm, ad);
4264         if (err)
4265                 goto out;
4266
4267         if (send_perm) {
4268                 u32 port_sid;
4269
4270                 err = security_port_sid(sk->sk_family,
4271                                         sk->sk_type,
4272                                         sk->sk_protocol,
4273                                         ntohs(ad->u.net.dport),
4274                                         &port_sid);
4275                 if (err)
4276                         goto out;
4277
4278                 err = avc_has_perm(isec->sid, port_sid, isec->sclass,
4279                                    send_perm, ad);
4280         }
4281 out:
4282         return err;
4283 }
4284
4285 static unsigned int selinux_ip_postroute_last(unsigned int hooknum,
4286                                               struct sk_buff *skb,
4287                                               const struct net_device *in,
4288                                               const struct net_device *out,
4289                                               int (*okfn)(struct sk_buff *),
4290                                               u16 family)
4291 {
4292         char *addrp;
4293         int err = 0;
4294         struct sock *sk;
4295         struct avc_audit_data ad;
4296         struct net_device *dev = (struct net_device *)out;
4297         struct sk_security_struct *sksec;
4298         u8 proto;
4299
4300         sk = skb->sk;
4301         if (!sk)
4302                 goto out;
4303
4304         sksec = sk->sk_security;
4305
4306         AVC_AUDIT_DATA_INIT(&ad, NET);
4307         ad.u.net.netif = dev->ifindex;
4308         ad.u.net.family = family;
4309
4310         err = selinux_parse_skb(skb, &ad, &addrp, 0, &proto);
4311         if (err)
4312                 goto out;
4313
4314         if (selinux_compat_net)
4315                 err = selinux_ip_postroute_last_compat(sk, dev, &ad,
4316                                                        family, addrp);
4317         else
4318                 err = avc_has_perm(sksec->sid, skb->secmark, SECCLASS_PACKET,
4319                                    PACKET__SEND, &ad);
4320
4321         if (err)
4322                 goto out;
4323
4324         err = selinux_xfrm_postroute_last(sksec->sid, skb, &ad, proto);
4325 out:
4326         return err ? NF_DROP : NF_ACCEPT;
4327 }
4328
4329 static unsigned int selinux_ipv4_postroute_last(unsigned int hooknum,
4330                                                 struct sk_buff *skb,
4331                                                 const struct net_device *in,
4332                                                 const struct net_device *out,
4333                                                 int (*okfn)(struct sk_buff *))
4334 {
4335         return selinux_ip_postroute_last(hooknum, skb, in, out, okfn, PF_INET);
4336 }
4337
4338 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
4339
4340 static unsigned int selinux_ipv6_postroute_last(unsigned int hooknum,
4341                                                 struct sk_buff *skb,
4342                                                 const struct net_device *in,
4343                                                 const struct net_device *out,
4344                                                 int (*okfn)(struct sk_buff *))
4345 {
4346         return selinux_ip_postroute_last(hooknum, skb, in, out, okfn, PF_INET6);
4347 }
4348
4349 #endif  /* IPV6 */
4350
4351 #endif  /* CONFIG_NETFILTER */
4352
4353 static int selinux_netlink_send(struct sock *sk, struct sk_buff *skb)
4354 {
4355         int err;
4356
4357         err = secondary_ops->netlink_send(sk, skb);
4358         if (err)
4359                 return err;
4360
4361         if (policydb_loaded_version >= POLICYDB_VERSION_NLCLASS)
4362                 err = selinux_nlmsg_perm(sk, skb);
4363
4364         return err;
4365 }
4366
4367 static int selinux_netlink_recv(struct sk_buff *skb, int capability)
4368 {
4369         int err;
4370         struct avc_audit_data ad;
4371
4372         err = secondary_ops->netlink_recv(skb, capability);
4373         if (err)
4374                 return err;
4375
4376         AVC_AUDIT_DATA_INIT(&ad, CAP);
4377         ad.u.cap = capability;
4378
4379         return avc_has_perm(NETLINK_CB(skb).sid, NETLINK_CB(skb).sid,
4380                             SECCLASS_CAPABILITY, CAP_TO_MASK(capability), &ad);
4381 }
4382
4383 static int ipc_alloc_security(struct task_struct *task,
4384                               struct kern_ipc_perm *perm,
4385                               u16 sclass)
4386 {
4387         struct task_security_struct *tsec = task->security;
4388         struct ipc_security_struct *isec;
4389
4390         isec = kzalloc(sizeof(struct ipc_security_struct), GFP_KERNEL);
4391         if (!isec)
4392                 return -ENOMEM;
4393
4394         isec->sclass = sclass;
4395         isec->ipc_perm = perm;
4396         isec->sid = tsec->sid;
4397         perm->security = isec;
4398
4399         return 0;
4400 }
4401
4402 static void ipc_free_security(struct kern_ipc_perm *perm)
4403 {
4404         struct ipc_security_struct *isec = perm->security;
4405         perm->security = NULL;
4406         kfree(isec);
4407 }
4408
4409 static int msg_msg_alloc_security(struct msg_msg *msg)
4410 {
4411         struct msg_security_struct *msec;
4412
4413         msec = kzalloc(sizeof(struct msg_security_struct), GFP_KERNEL);
4414         if (!msec)
4415                 return -ENOMEM;
4416
4417         msec->msg = msg;
4418         msec->sid = SECINITSID_UNLABELED;
4419         msg->security = msec;
4420
4421         return 0;
4422 }
4423
4424 static void msg_msg_free_security(struct msg_msg *msg)
4425 {
4426         struct msg_security_struct *msec = msg->security;
4427
4428         msg->security = NULL;
4429         kfree(msec);
4430 }
4431
4432 static int ipc_has_perm(struct kern_ipc_perm *ipc_perms,
4433                         u32 perms)
4434 {
4435         struct task_security_struct *tsec;
4436         struct ipc_security_struct *isec;
4437         struct avc_audit_data ad;
4438
4439         tsec = current->security;
4440         isec = ipc_perms->security;
4441
4442         AVC_AUDIT_DATA_INIT(&ad, IPC);
4443         ad.u.ipc_id = ipc_perms->key;
4444
4445         return avc_has_perm(tsec->sid, isec->sid, isec->sclass, perms, &ad);
4446 }
4447
4448 static int selinux_msg_msg_alloc_security(struct msg_msg *msg)
4449 {
4450         return msg_msg_alloc_security(msg);
4451 }
4452
4453 static void selinux_msg_msg_free_security(struct msg_msg *msg)
4454 {
4455         msg_msg_free_security(msg);
4456 }
4457
4458 /* message queue security operations */
4459 static int selinux_msg_queue_alloc_security(struct msg_queue *msq)
4460 {
4461         struct task_security_struct *tsec;
4462         struct ipc_security_struct *isec;
4463         struct avc_audit_data ad;
4464         int rc;
4465
4466         rc = ipc_alloc_security(current, &msq->q_perm, SECCLASS_MSGQ);
4467         if (rc)
4468                 return rc;
4469
4470         tsec = current->security;
4471         isec = msq->q_perm.security;
4472
4473         AVC_AUDIT_DATA_INIT(&ad, IPC);
4474         ad.u.ipc_id = msq->q_perm.key;
4475
4476         rc = avc_has_perm(tsec->sid, isec->sid, SECCLASS_MSGQ,
4477                           MSGQ__CREATE, &ad);
4478         if (rc) {
4479                 ipc_free_security(&msq->q_perm);
4480                 return rc;
4481         }
4482         return 0;
4483 }
4484
4485 static void selinux_msg_queue_free_security(struct msg_queue *msq)
4486 {
4487         ipc_free_security(&msq->q_perm);
4488 }
4489
4490 static int selinux_msg_queue_associate(struct msg_queue *msq, int msqflg)
4491 {
4492         struct task_security_struct *tsec;
4493         struct ipc_security_struct *isec;
4494         struct avc_audit_data ad;
4495
4496         tsec = current->security;
4497         isec = msq->q_perm.security;
4498
4499         AVC_AUDIT_DATA_INIT(&ad, IPC);
4500         ad.u.ipc_id = msq->q_perm.key;
4501
4502         return avc_has_perm(tsec->sid, isec->sid, SECCLASS_MSGQ,
4503                             MSGQ__ASSOCIATE, &ad);
4504 }
4505
4506 static int selinux_msg_queue_msgctl(struct msg_queue *msq, int cmd)
4507 {
4508         int err;
4509         int perms;
4510
4511         switch(cmd) {
4512         case IPC_INFO:
4513         case MSG_INFO:
4514                 /* No specific object, just general system-wide information. */
4515                 return task_has_system(current, SYSTEM__IPC_INFO);
4516         case IPC_STAT:
4517         case MSG_STAT:
4518                 perms = MSGQ__GETATTR | MSGQ__ASSOCIATE;
4519                 break;
4520         case IPC_SET:
4521                 perms = MSGQ__SETATTR;
4522                 break;
4523         case IPC_RMID:
4524                 perms = MSGQ__DESTROY;
4525                 break;
4526         default:
4527                 return 0;
4528         }
4529
4530         err = ipc_has_perm(&msq->q_perm, perms);
4531         return err;
4532 }
4533
4534 static int selinux_msg_queue_msgsnd(struct msg_queue *msq, struct msg_msg *msg, int msqflg)
4535 {
4536         struct task_security_struct *tsec;
4537         struct ipc_security_struct *isec;
4538         struct msg_security_struct *msec;
4539         struct avc_audit_data ad;
4540         int rc;
4541
4542         tsec = current->security;
4543         isec = msq->q_perm.security;
4544         msec = msg->security;
4545
4546         /*
4547          * First time through, need to assign label to the message
4548          */
4549         if (msec->sid == SECINITSID_UNLABELED) {
4550                 /*
4551                  * Compute new sid based on current process and
4552                  * message queue this message will be stored in
4553                  */
4554                 rc = security_transition_sid(tsec->sid,
4555                                              isec->sid,
4556                                              SECCLASS_MSG,
4557                                              &msec->sid);
4558                 if (rc)
4559                         return rc;
4560         }
4561
4562         AVC_AUDIT_DATA_INIT(&ad, IPC);
4563         ad.u.ipc_id = msq->q_perm.key;
4564
4565         /* Can this process write to the queue? */
4566         rc = avc_has_perm(tsec->sid, isec->sid, SECCLASS_MSGQ,
4567                           MSGQ__WRITE, &ad);
4568         if (!rc)
4569                 /* Can this process send the message */
4570                 rc = avc_has_perm(tsec->sid, msec->sid,
4571                                   SECCLASS_MSG, MSG__SEND, &ad);
4572         if (!rc)
4573                 /* Can the message be put in the queue? */
4574                 rc = avc_has_perm(msec->sid, isec->sid,
4575                                   SECCLASS_MSGQ, MSGQ__ENQUEUE, &ad);
4576
4577         return rc;
4578 }
4579
4580 static int selinux_msg_queue_msgrcv(struct msg_queue *msq, struct msg_msg *msg,
4581                                     struct task_struct *target,
4582                                     long type, int mode)
4583 {
4584         struct task_security_struct *tsec;
4585         struct ipc_security_struct *isec;
4586         struct msg_security_struct *msec;
4587         struct avc_audit_data ad;
4588         int rc;
4589
4590         tsec = target->security;
4591         isec = msq->q_perm.security;
4592         msec = msg->security;
4593
4594         AVC_AUDIT_DATA_INIT(&ad, IPC);
4595         ad.u.ipc_id = msq->q_perm.key;
4596
4597         rc = avc_has_perm(tsec->sid, isec->sid,
4598                           SECCLASS_MSGQ, MSGQ__READ, &ad);
4599         if (!rc)
4600                 rc = avc_has_perm(tsec->sid, msec->sid,
4601                                   SECCLASS_MSG, MSG__RECEIVE, &ad);
4602         return rc;
4603 }
4604
4605 /* Shared Memory security operations */
4606 static int selinux_shm_alloc_security(struct shmid_kernel *shp)
4607 {
4608         struct task_security_struct *tsec;
4609         struct ipc_security_struct *isec;
4610         struct avc_audit_data ad;
4611         int rc;
4612
4613         rc = ipc_alloc_security(current, &shp->shm_perm, SECCLASS_SHM);
4614         if (rc)
4615                 return rc;
4616
4617         tsec = current->security;
4618         isec = shp->shm_perm.security;
4619
4620         AVC_AUDIT_DATA_INIT(&ad, IPC);
4621         ad.u.ipc_id = shp->shm_perm.key;
4622
4623         rc = avc_has_perm(tsec->sid, isec->sid, SECCLASS_SHM,
4624                           SHM__CREATE, &ad);
4625         if (rc) {
4626                 ipc_free_security(&shp->shm_perm);
4627                 return rc;
4628         }
4629         return 0;
4630 }
4631
4632 static void selinux_shm_free_security(struct shmid_kernel *shp)
4633 {
4634         ipc_free_security(&shp->shm_perm);
4635 }
4636
4637 static int selinux_shm_associate(struct shmid_kernel *shp, int shmflg)
4638 {
4639         struct task_security_struct *tsec;
4640         struct ipc_security_struct *isec;
4641         struct avc_audit_data ad;
4642
4643         tsec = current->security;
4644         isec = shp->shm_perm.security;
4645
4646         AVC_AUDIT_DATA_INIT(&ad, IPC);
4647         ad.u.ipc_id = shp->shm_perm.key;
4648
4649         return avc_has_perm(tsec->sid, isec->sid, SECCLASS_SHM,
4650                             SHM__ASSOCIATE, &ad);
4651 }
4652
4653 /* Note, at this point, shp is locked down */
4654 static int selinux_shm_shmctl(struct shmid_kernel *shp, int cmd)
4655 {
4656         int perms;
4657         int err;
4658
4659         switch(cmd) {
4660         case IPC_INFO:
4661         case SHM_INFO:
4662                 /* No specific object, just general system-wide information. */
4663                 return task_has_system(current, SYSTEM__IPC_INFO);
4664         case IPC_STAT:
4665         case SHM_STAT:
4666                 perms = SHM__GETATTR | SHM__ASSOCIATE;
4667                 break;
4668         case IPC_SET:
4669                 perms = SHM__SETATTR;
4670                 break;
4671         case SHM_LOCK:
4672         case SHM_UNLOCK:
4673                 perms = SHM__LOCK;
4674                 break;
4675         case IPC_RMID:
4676                 perms = SHM__DESTROY;
4677                 break;
4678         default:
4679                 return 0;
4680         }
4681
4682         err = ipc_has_perm(&shp->shm_perm, perms);
4683         return err;
4684 }
4685
4686 static int selinux_shm_shmat(struct shmid_kernel *shp,
4687                              char __user *shmaddr, int shmflg)
4688 {
4689         u32 perms;
4690         int rc;
4691
4692         rc = secondary_ops->shm_shmat(shp, shmaddr, shmflg);
4693         if (rc)
4694                 return rc;
4695
4696         if (shmflg & SHM_RDONLY)
4697                 perms = SHM__READ;
4698         else
4699                 perms = SHM__READ | SHM__WRITE;
4700
4701         return ipc_has_perm(&shp->shm_perm, perms);
4702 }
4703
4704 /* Semaphore security operations */
4705 static int selinux_sem_alloc_security(struct sem_array *sma)
4706 {
4707         struct task_security_struct *tsec;
4708         struct ipc_security_struct *isec;
4709         struct avc_audit_data ad;
4710         int rc;
4711
4712         rc = ipc_alloc_security(current, &sma->sem_perm, SECCLASS_SEM);
4713         if (rc)
4714                 return rc;
4715
4716         tsec = current->security;
4717         isec = sma->sem_perm.security;
4718
4719         AVC_AUDIT_DATA_INIT(&ad, IPC);
4720         ad.u.ipc_id = sma->sem_perm.key;
4721
4722         rc = avc_has_perm(tsec->sid, isec->sid, SECCLASS_SEM,
4723                           SEM__CREATE, &ad);
4724         if (rc) {
4725                 ipc_free_security(&sma->sem_perm);
4726                 return rc;
4727         }
4728         return 0;
4729 }
4730
4731 static void selinux_sem_free_security(struct sem_array *sma)
4732 {
4733         ipc_free_security(&sma->sem_perm);
4734 }
4735
4736 static int selinux_sem_associate(struct sem_array *sma, int semflg)
4737 {
4738         struct task_security_struct *tsec;
4739         struct ipc_security_struct *isec;
4740         struct avc_audit_data ad;
4741
4742         tsec = current->security;
4743         isec = sma->sem_perm.security;
4744
4745         AVC_AUDIT_DATA_INIT(&ad, IPC);
4746         ad.u.ipc_id = sma->sem_perm.key;
4747
4748         return avc_has_perm(tsec->sid, isec->sid, SECCLASS_SEM,
4749                             SEM__ASSOCIATE, &ad);
4750 }
4751
4752 /* Note, at this point, sma is locked down */
4753 static int selinux_sem_semctl(struct sem_array *sma, int cmd)
4754 {
4755         int err;
4756         u32 perms;
4757
4758         switch(cmd) {
4759         case IPC_INFO:
4760         case SEM_INFO:
4761                 /* No specific object, just general system-wide information. */
4762                 return task_has_system(current, SYSTEM__IPC_INFO);
4763         case GETPID:
4764         case GETNCNT:
4765         case GETZCNT:
4766                 perms = SEM__GETATTR;
4767                 break;
4768         case GETVAL:
4769         case GETALL:
4770                 perms = SEM__READ;
4771                 break;
4772         case SETVAL:
4773         case SETALL:
4774                 perms = SEM__WRITE;
4775                 break;
4776         case IPC_RMID:
4777                 perms = SEM__DESTROY;
4778                 break;
4779         case IPC_SET:
4780                 perms = SEM__SETATTR;
4781                 break;
4782         case IPC_STAT:
4783         case SEM_STAT:
4784                 perms = SEM__GETATTR | SEM__ASSOCIATE;
4785                 break;
4786         default:
4787                 return 0;
4788         }
4789
4790         err = ipc_has_perm(&sma->sem_perm, perms);
4791         return err;
4792 }
4793
4794 static int selinux_sem_semop(struct sem_array *sma,
4795                              struct sembuf *sops, unsigned nsops, int alter)
4796 {
4797         u32 perms;
4798
4799         if (alter)
4800                 perms = SEM__READ | SEM__WRITE;
4801         else
4802                 perms = SEM__READ;
4803
4804         return ipc_has_perm(&sma->sem_perm, perms);
4805 }
4806
4807 static int selinux_ipc_permission(struct kern_ipc_perm *ipcp, short flag)
4808 {
4809         u32 av = 0;
4810
4811         av = 0;
4812         if (flag & S_IRUGO)
4813                 av |= IPC__UNIX_READ;
4814         if (flag & S_IWUGO)
4815                 av |= IPC__UNIX_WRITE;
4816
4817         if (av == 0)
4818                 return 0;
4819
4820         return ipc_has_perm(ipcp, av);
4821 }
4822
4823 /* module stacking operations */
4824 static int selinux_register_security (const char *name, struct security_operations *ops)
4825 {
4826         if (secondary_ops != original_ops) {
4827                 printk(KERN_ERR "%s:  There is already a secondary security "
4828                        "module registered.\n", __FUNCTION__);
4829                 return -EINVAL;
4830         }
4831
4832         secondary_ops = ops;
4833
4834         printk(KERN_INFO "%s:  Registering secondary module %s\n",
4835                __FUNCTION__,
4836                name);
4837
4838         return 0;
4839 }
4840
4841 static void selinux_d_instantiate (struct dentry *dentry, struct inode *inode)
4842 {
4843         if (inode)
4844                 inode_doinit_with_dentry(inode, dentry);
4845 }
4846
4847 static int selinux_getprocattr(struct task_struct *p,
4848                                char *name, char **value)
4849 {
4850         struct task_security_struct *tsec;
4851         u32 sid;
4852         int error;
4853         unsigned len;
4854
4855         if (current != p) {
4856                 error = task_has_perm(current, p, PROCESS__GETATTR);
4857                 if (error)
4858                         return error;
4859         }
4860
4861         tsec = p->security;
4862
4863         if (!strcmp(name, "current"))
4864                 sid = tsec->sid;
4865         else if (!strcmp(name, "prev"))
4866                 sid = tsec->osid;
4867         else if (!strcmp(name, "exec"))
4868                 sid = tsec->exec_sid;
4869         else if (!strcmp(name, "fscreate"))
4870                 sid = tsec->create_sid;
4871         else if (!strcmp(name, "keycreate"))
4872                 sid = tsec->keycreate_sid;
4873         else if (!strcmp(name, "sockcreate"))
4874                 sid = tsec->sockcreate_sid;
4875         else
4876                 return -EINVAL;
4877
4878         if (!sid)
4879                 return 0;
4880
4881         error = security_sid_to_context(sid, value, &len);
4882         if (error)
4883                 return error;
4884         return len;
4885 }
4886
4887 static int selinux_setprocattr(struct task_struct *p,
4888                                char *name, void *value, size_t size)
4889 {
4890         struct task_security_struct *tsec;
4891         u32 sid = 0;
4892         int error;
4893         char *str = value;
4894
4895         if (current != p) {
4896                 /* SELinux only allows a process to change its own
4897                    security attributes. */
4898                 return -EACCES;
4899         }
4900
4901         /*
4902          * Basic control over ability to set these attributes at all.
4903          * current == p, but we'll pass them separately in case the
4904          * above restriction is ever removed.
4905          */
4906         if (!strcmp(name, "exec"))
4907                 error = task_has_perm(current, p, PROCESS__SETEXEC);
4908         else if (!strcmp(name, "fscreate"))
4909                 error = task_has_perm(current, p, PROCESS__SETFSCREATE);
4910         else if (!strcmp(name, "keycreate"))
4911                 error = task_has_perm(current, p, PROCESS__SETKEYCREATE);
4912         else if (!strcmp(name, "sockcreate"))
4913                 error = task_has_perm(current, p, PROCESS__SETSOCKCREATE);
4914         else if (!strcmp(name, "current"))
4915                 error = task_has_perm(current, p, PROCESS__SETCURRENT);
4916         else
4917                 error = -EINVAL;
4918         if (error)
4919                 return error;
4920
4921         /* Obtain a SID for the context, if one was specified. */
4922         if (size && str[1] && str[1] != '\n') {
4923                 if (str[size-1] == '\n') {
4924                         str[size-1] = 0;
4925                         size--;
4926                 }
4927                 error = security_context_to_sid(value, size, &sid);
4928                 if (error)
4929                         return error;
4930         }
4931
4932         /* Permission checking based on the specified context is
4933            performed during the actual operation (execve,
4934            open/mkdir/...), when we know the full context of the
4935            operation.  See selinux_bprm_set_security for the execve
4936            checks and may_create for the file creation checks. The
4937            operation will then fail if the context is not permitted. */
4938         tsec = p->security;
4939         if (!strcmp(name, "exec"))
4940                 tsec->exec_sid = sid;
4941         else if (!strcmp(name, "fscreate"))
4942                 tsec->create_sid = sid;
4943         else if (!strcmp(name, "keycreate")) {
4944                 error = may_create_key(sid, p);
4945                 if (error)
4946                         return error;
4947                 tsec->keycreate_sid = sid;
4948         } else if (!strcmp(name, "sockcreate"))
4949                 tsec->sockcreate_sid = sid;
4950         else if (!strcmp(name, "current")) {
4951                 struct av_decision avd;
4952
4953                 if (sid == 0)
4954                         return -EINVAL;
4955
4956                 /* Only allow single threaded processes to change context */
4957                 if (atomic_read(&p->mm->mm_users) != 1) {
4958                         struct task_struct *g, *t;
4959                         struct mm_struct *mm = p->mm;
4960                         read_lock(&tasklist_lock);
4961                         do_each_thread(g, t)
4962                                 if (t->mm == mm && t != p) {
4963                                         read_unlock(&tasklist_lock);
4964                                         return -EPERM;
4965                                 }
4966                         while_each_thread(g, t);
4967                         read_unlock(&tasklist_lock);
4968                 }
4969
4970                 /* Check permissions for the transition. */
4971                 error = avc_has_perm(tsec->sid, sid, SECCLASS_PROCESS,
4972                                      PROCESS__DYNTRANSITION, NULL);
4973                 if (error)
4974                         return error;
4975
4976                 /* Check for ptracing, and update the task SID if ok.
4977                    Otherwise, leave SID unchanged and fail. */
4978                 task_lock(p);
4979                 if (p->ptrace & PT_PTRACED) {
4980                         error = avc_has_perm_noaudit(tsec->ptrace_sid, sid,
4981                                                      SECCLASS_PROCESS,
4982                                                      PROCESS__PTRACE, 0, &avd);
4983                         if (!error)
4984                                 tsec->sid = sid;
4985                         task_unlock(p);
4986                         avc_audit(tsec->ptrace_sid, sid, SECCLASS_PROCESS,
4987                                   PROCESS__PTRACE, &avd, error, NULL);
4988                         if (error)
4989                                 return error;
4990                 } else {
4991                         tsec->sid = sid;
4992                         task_unlock(p);
4993                 }
4994         }
4995         else
4996                 return -EINVAL;
4997
4998         return size;
4999 }
5000
5001 static int selinux_secid_to_secctx(u32 secid, char **secdata, u32 *seclen)
5002 {
5003         return security_sid_to_context(secid, secdata, seclen);
5004 }
5005
5006 static int selinux_secctx_to_secid(char *secdata, u32 seclen, u32 *secid)
5007 {
5008         return security_context_to_sid(secdata, seclen, secid);
5009 }
5010
5011 static void selinux_release_secctx(char *secdata, u32 seclen)
5012 {
5013         kfree(secdata);
5014 }
5015
5016 #ifdef CONFIG_KEYS
5017
5018 static int selinux_key_alloc(struct key *k, struct task_struct *tsk,
5019                              unsigned long flags)
5020 {
5021         struct task_security_struct *tsec = tsk->security;
5022         struct key_security_struct *ksec;
5023
5024         ksec = kzalloc(sizeof(struct key_security_struct), GFP_KERNEL);
5025         if (!ksec)
5026                 return -ENOMEM;
5027
5028         ksec->obj = k;
5029         if (tsec->keycreate_sid)
5030                 ksec->sid = tsec->keycreate_sid;
5031         else
5032                 ksec->sid = tsec->sid;
5033         k->security = ksec;
5034
5035         return 0;
5036 }
5037
5038 static void selinux_key_free(struct key *k)
5039 {
5040         struct key_security_struct *ksec = k->security;
5041
5042         k->security = NULL;
5043         kfree(ksec);
5044 }
5045
5046 static int selinux_key_permission(key_ref_t key_ref,
5047                             struct task_struct *ctx,
5048                             key_perm_t perm)
5049 {
5050         struct key *key;
5051         struct task_security_struct *tsec;
5052         struct key_security_struct *ksec;
5053
5054         key = key_ref_to_ptr(key_ref);
5055
5056         tsec = ctx->security;
5057         ksec = key->security;
5058
5059         /* if no specific permissions are requested, we skip the
5060            permission check. No serious, additional covert channels
5061            appear to be created. */
5062         if (perm == 0)
5063                 return 0;
5064
5065         return avc_has_perm(tsec->sid, ksec->sid,
5066                             SECCLASS_KEY, perm, NULL);
5067 }
5068
5069 #endif
5070
5071 static struct security_operations selinux_ops = {
5072         .ptrace =                       selinux_ptrace,
5073         .capget =                       selinux_capget,
5074         .capset_check =                 selinux_capset_check,
5075         .capset_set =                   selinux_capset_set,
5076         .sysctl =                       selinux_sysctl,
5077         .capable =                      selinux_capable,
5078         .quotactl =                     selinux_quotactl,
5079         .quota_on =                     selinux_quota_on,
5080         .syslog =                       selinux_syslog,
5081         .vm_enough_memory =             selinux_vm_enough_memory,
5082
5083         .netlink_send =                 selinux_netlink_send,
5084         .netlink_recv =                 selinux_netlink_recv,
5085
5086         .bprm_alloc_security =          selinux_bprm_alloc_security,
5087         .bprm_free_security =           selinux_bprm_free_security,
5088         .bprm_apply_creds =             selinux_bprm_apply_creds,
5089         .bprm_post_apply_creds =        selinux_bprm_post_apply_creds,
5090         .bprm_set_security =            selinux_bprm_set_security,
5091         .bprm_check_security =          selinux_bprm_check_security,
5092         .bprm_secureexec =              selinux_bprm_secureexec,
5093
5094         .sb_alloc_security =            selinux_sb_alloc_security,
5095         .sb_free_security =             selinux_sb_free_security,
5096         .sb_copy_data =                 selinux_sb_copy_data,
5097         .sb_kern_mount =                selinux_sb_kern_mount,
5098         .sb_statfs =                    selinux_sb_statfs,
5099         .sb_mount =                     selinux_mount,
5100         .sb_umount =                    selinux_umount,
5101         .sb_get_mnt_opts =              selinux_get_mnt_opts,
5102         .sb_set_mnt_opts =              selinux_set_mnt_opts,
5103         .sb_clone_mnt_opts =            selinux_sb_clone_mnt_opts,
5104
5105         .inode_alloc_security =         selinux_inode_alloc_security,
5106         .inode_free_security =          selinux_inode_free_security,
5107         .inode_init_security =          selinux_inode_init_security,
5108         .inode_create =                 selinux_inode_create,
5109         .inode_link =                   selinux_inode_link,
5110         .inode_unlink =                 selinux_inode_unlink,
5111         .inode_symlink =                selinux_inode_symlink,
5112         .inode_mkdir =                  selinux_inode_mkdir,
5113         .inode_rmdir =                  selinux_inode_rmdir,
5114         .inode_mknod =                  selinux_inode_mknod,
5115         .inode_rename =                 selinux_inode_rename,
5116         .inode_readlink =               selinux_inode_readlink,
5117         .inode_follow_link =            selinux_inode_follow_link,
5118         .inode_permission =             selinux_inode_permission,
5119         .inode_setattr =                selinux_inode_setattr,
5120         .inode_getattr =                selinux_inode_getattr,
5121         .inode_setxattr =               selinux_inode_setxattr,
5122         .inode_post_setxattr =          selinux_inode_post_setxattr,
5123         .inode_getxattr =               selinux_inode_getxattr,
5124         .inode_listxattr =              selinux_inode_listxattr,
5125         .inode_removexattr =            selinux_inode_removexattr,
5126         .inode_getsecurity =            selinux_inode_getsecurity,
5127         .inode_setsecurity =            selinux_inode_setsecurity,
5128         .inode_listsecurity =           selinux_inode_listsecurity,
5129         .inode_need_killpriv =          selinux_inode_need_killpriv,
5130         .inode_killpriv =               selinux_inode_killpriv,
5131
5132         .file_permission =              selinux_file_permission,
5133         .file_alloc_security =          selinux_file_alloc_security,
5134         .file_free_security =           selinux_file_free_security,
5135         .file_ioctl =                   selinux_file_ioctl,
5136         .file_mmap =                    selinux_file_mmap,
5137         .file_mprotect =                selinux_file_mprotect,
5138         .file_lock =                    selinux_file_lock,
5139         .file_fcntl =                   selinux_file_fcntl,
5140         .file_set_fowner =              selinux_file_set_fowner,
5141         .file_send_sigiotask =          selinux_file_send_sigiotask,
5142         .file_receive =                 selinux_file_receive,
5143
5144         .dentry_open =                  selinux_dentry_open,
5145
5146         .task_create =                  selinux_task_create,
5147         .task_alloc_security =          selinux_task_alloc_security,
5148         .task_free_security =           selinux_task_free_security,
5149         .task_setuid =                  selinux_task_setuid,
5150         .task_post_setuid =             selinux_task_post_setuid,
5151         .task_setgid =                  selinux_task_setgid,
5152         .task_setpgid =                 selinux_task_setpgid,
5153         .task_getpgid =                 selinux_task_getpgid,
5154         .task_getsid =                  selinux_task_getsid,
5155         .task_getsecid =                selinux_task_getsecid,
5156         .task_setgroups =               selinux_task_setgroups,
5157         .task_setnice =                 selinux_task_setnice,
5158         .task_setioprio =               selinux_task_setioprio,
5159         .task_getioprio =               selinux_task_getioprio,
5160         .task_setrlimit =               selinux_task_setrlimit,
5161         .task_setscheduler =            selinux_task_setscheduler,
5162         .task_getscheduler =            selinux_task_getscheduler,
5163         .task_movememory =              selinux_task_movememory,
5164         .task_kill =                    selinux_task_kill,
5165         .task_wait =                    selinux_task_wait,
5166         .task_prctl =                   selinux_task_prctl,
5167         .task_reparent_to_init =        selinux_task_reparent_to_init,
5168         .task_to_inode =                selinux_task_to_inode,
5169
5170         .ipc_permission =               selinux_ipc_permission,
5171
5172         .msg_msg_alloc_security =       selinux_msg_msg_alloc_security,
5173         .msg_msg_free_security =        selinux_msg_msg_free_security,
5174
5175         .msg_queue_alloc_security =     selinux_msg_queue_alloc_security,
5176         .msg_queue_free_security =      selinux_msg_queue_free_security,
5177         .msg_queue_associate =          selinux_msg_queue_associate,
5178         .msg_queue_msgctl =             selinux_msg_queue_msgctl,
5179         .msg_queue_msgsnd =             selinux_msg_queue_msgsnd,
5180         .msg_queue_msgrcv =             selinux_msg_queue_msgrcv,
5181
5182         .shm_alloc_security =           selinux_shm_alloc_security,
5183         .shm_free_security =            selinux_shm_free_security,
5184         .shm_associate =                selinux_shm_associate,
5185         .shm_shmctl =                   selinux_shm_shmctl,
5186         .shm_shmat =                    selinux_shm_shmat,
5187
5188         .sem_alloc_security =           selinux_sem_alloc_security,
5189         .sem_free_security =            selinux_sem_free_security,
5190         .sem_associate =                selinux_sem_associate,
5191         .sem_semctl =                   selinux_sem_semctl,
5192         .sem_semop =                    selinux_sem_semop,
5193
5194         .register_security =            selinux_register_security,
5195
5196         .d_instantiate =                selinux_d_instantiate,
5197
5198         .getprocattr =                  selinux_getprocattr,
5199         .setprocattr =                  selinux_setprocattr,
5200
5201         .secid_to_secctx =              selinux_secid_to_secctx,
5202         .secctx_to_secid =              selinux_secctx_to_secid,
5203         .release_secctx =               selinux_release_secctx,
5204
5205         .unix_stream_connect =          selinux_socket_unix_stream_connect,
5206         .unix_may_send =                selinux_socket_unix_may_send,
5207
5208         .socket_create =                selinux_socket_create,
5209         .socket_post_create =           selinux_socket_post_create,
5210         .socket_bind =                  selinux_socket_bind,
5211         .socket_connect =               selinux_socket_connect,
5212         .socket_listen =                selinux_socket_listen,
5213         .socket_accept =                selinux_socket_accept,
5214         .socket_sendmsg =               selinux_socket_sendmsg,
5215         .socket_recvmsg =               selinux_socket_recvmsg,
5216         .socket_getsockname =           selinux_socket_getsockname,
5217         .socket_getpeername =           selinux_socket_getpeername,
5218         .socket_getsockopt =            selinux_socket_getsockopt,
5219         .socket_setsockopt =            selinux_socket_setsockopt,
5220         .socket_shutdown =              selinux_socket_shutdown,
5221         .socket_sock_rcv_skb =          selinux_socket_sock_rcv_skb,
5222         .socket_getpeersec_stream =     selinux_socket_getpeersec_stream,
5223         .socket_getpeersec_dgram =      selinux_socket_getpeersec_dgram,
5224         .sk_alloc_security =            selinux_sk_alloc_security,
5225         .sk_free_security =             selinux_sk_free_security,
5226         .sk_clone_security =            selinux_sk_clone_security,
5227         .sk_getsecid =                  selinux_sk_getsecid,
5228         .sock_graft =                   selinux_sock_graft,
5229         .inet_conn_request =            selinux_inet_conn_request,
5230         .inet_csk_clone =               selinux_inet_csk_clone,
5231         .inet_conn_established =        selinux_inet_conn_established,
5232         .req_classify_flow =            selinux_req_classify_flow,
5233
5234 #ifdef CONFIG_SECURITY_NETWORK_XFRM
5235         .xfrm_policy_alloc_security =   selinux_xfrm_policy_alloc,
5236         .xfrm_policy_clone_security =   selinux_xfrm_policy_clone,
5237         .xfrm_policy_free_security =    selinux_xfrm_policy_free,
5238         .xfrm_policy_delete_security =  selinux_xfrm_policy_delete,
5239         .xfrm_state_alloc_security =    selinux_xfrm_state_alloc,
5240         .xfrm_state_free_security =     selinux_xfrm_state_free,
5241         .xfrm_state_delete_security =   selinux_xfrm_state_delete,
5242         .xfrm_policy_lookup =           selinux_xfrm_policy_lookup,
5243         .xfrm_state_pol_flow_match =    selinux_xfrm_state_pol_flow_match,
5244         .xfrm_decode_session =          selinux_xfrm_decode_session,
5245 #endif
5246
5247 #ifdef CONFIG_KEYS
5248         .key_alloc =                    selinux_key_alloc,
5249         .key_free =                     selinux_key_free,
5250         .key_permission =               selinux_key_permission,
5251 #endif
5252 };
5253
5254 static __init int selinux_init(void)
5255 {
5256         struct task_security_struct *tsec;
5257
5258         if (!selinux_enabled) {
5259                 printk(KERN_INFO "SELinux:  Disabled at boot.\n");
5260                 return 0;
5261         }
5262
5263         printk(KERN_INFO "SELinux:  Initializing.\n");
5264
5265         /* Set the security state for the initial task. */
5266         if (task_alloc_security(current))
5267                 panic("SELinux:  Failed to initialize initial task.\n");
5268         tsec = current->security;
5269         tsec->osid = tsec->sid = SECINITSID_KERNEL;
5270
5271         sel_inode_cache = kmem_cache_create("selinux_inode_security",
5272                                             sizeof(struct inode_security_struct),
5273                                             0, SLAB_PANIC, NULL);
5274         avc_init();
5275
5276         original_ops = secondary_ops = security_ops;
5277         if (!secondary_ops)
5278                 panic ("SELinux: No initial security operations\n");
5279         if (register_security (&selinux_ops))
5280                 panic("SELinux: Unable to register with kernel.\n");
5281
5282         if (selinux_enforcing) {
5283                 printk(KERN_DEBUG "SELinux:  Starting in enforcing mode\n");
5284         } else {
5285                 printk(KERN_DEBUG "SELinux:  Starting in permissive mode\n");
5286         }
5287
5288 #ifdef CONFIG_KEYS
5289         /* Add security information to initial keyrings */
5290         selinux_key_alloc(&root_user_keyring, current,
5291                           KEY_ALLOC_NOT_IN_QUOTA);
5292         selinux_key_alloc(&root_session_keyring, current,
5293                           KEY_ALLOC_NOT_IN_QUOTA);
5294 #endif
5295
5296         return 0;
5297 }
5298
5299 void selinux_complete_init(void)
5300 {
5301         printk(KERN_DEBUG "SELinux:  Completing initialization.\n");
5302
5303         /* Set up any superblocks initialized prior to the policy load. */
5304         printk(KERN_DEBUG "SELinux:  Setting up existing superblocks.\n");
5305         spin_lock(&sb_lock);
5306         spin_lock(&sb_security_lock);
5307 next_sb:
5308         if (!list_empty(&superblock_security_head)) {
5309                 struct superblock_security_struct *sbsec =
5310                                 list_entry(superblock_security_head.next,
5311                                            struct superblock_security_struct,
5312                                            list);
5313                 struct super_block *sb = sbsec->sb;
5314                 sb->s_count++;
5315                 spin_unlock(&sb_security_lock);
5316                 spin_unlock(&sb_lock);
5317                 down_read(&sb->s_umount);
5318                 if (sb->s_root)
5319                         superblock_doinit(sb, NULL);
5320                 drop_super(sb);
5321                 spin_lock(&sb_lock);
5322                 spin_lock(&sb_security_lock);
5323                 list_del_init(&sbsec->list);
5324                 goto next_sb;
5325         }
5326         spin_unlock(&sb_security_lock);
5327         spin_unlock(&sb_lock);
5328 }
5329
5330 /* SELinux requires early initialization in order to label
5331    all processes and objects when they are created. */
5332 security_initcall(selinux_init);
5333
5334 #if defined(CONFIG_NETFILTER)
5335
5336 static struct nf_hook_ops selinux_ipv4_op = {
5337         .hook =         selinux_ipv4_postroute_last,
5338         .owner =        THIS_MODULE,
5339         .pf =           PF_INET,
5340         .hooknum =      NF_INET_POST_ROUTING,
5341         .priority =     NF_IP_PRI_SELINUX_LAST,
5342 };
5343
5344 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
5345
5346 static struct nf_hook_ops selinux_ipv6_op = {
5347         .hook =         selinux_ipv6_postroute_last,
5348         .owner =        THIS_MODULE,
5349         .pf =           PF_INET6,
5350         .hooknum =      NF_INET_POST_ROUTING,
5351         .priority =     NF_IP6_PRI_SELINUX_LAST,
5352 };
5353
5354 #endif  /* IPV6 */
5355
5356 static int __init selinux_nf_ip_init(void)
5357 {
5358         int err = 0;
5359
5360         if (!selinux_enabled)
5361                 goto out;
5362
5363         printk(KERN_DEBUG "SELinux:  Registering netfilter hooks\n");
5364
5365         err = nf_register_hook(&selinux_ipv4_op);
5366         if (err)
5367                 panic("SELinux: nf_register_hook for IPv4: error %d\n", err);
5368
5369 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
5370
5371         err = nf_register_hook(&selinux_ipv6_op);
5372         if (err)
5373                 panic("SELinux: nf_register_hook for IPv6: error %d\n", err);
5374
5375 #endif  /* IPV6 */
5376
5377 out:
5378         return err;
5379 }
5380
5381 __initcall(selinux_nf_ip_init);
5382
5383 #ifdef CONFIG_SECURITY_SELINUX_DISABLE
5384 static void selinux_nf_ip_exit(void)
5385 {
5386         printk(KERN_DEBUG "SELinux:  Unregistering netfilter hooks\n");
5387
5388         nf_unregister_hook(&selinux_ipv4_op);
5389 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
5390         nf_unregister_hook(&selinux_ipv6_op);
5391 #endif  /* IPV6 */
5392 }
5393 #endif
5394
5395 #else /* CONFIG_NETFILTER */
5396
5397 #ifdef CONFIG_SECURITY_SELINUX_DISABLE
5398 #define selinux_nf_ip_exit()
5399 #endif
5400
5401 #endif /* CONFIG_NETFILTER */
5402
5403 #ifdef CONFIG_SECURITY_SELINUX_DISABLE
5404 int selinux_disable(void)
5405 {
5406         extern void exit_sel_fs(void);
5407         static int selinux_disabled = 0;
5408
5409         if (ss_initialized) {
5410                 /* Not permitted after initial policy load. */
5411                 return -EINVAL;
5412         }
5413
5414         if (selinux_disabled) {
5415                 /* Only do this once. */
5416                 return -EINVAL;
5417         }
5418
5419         printk(KERN_INFO "SELinux:  Disabled at runtime.\n");
5420
5421         selinux_disabled = 1;
5422         selinux_enabled = 0;
5423
5424         /* Reset security_ops to the secondary module, dummy or capability. */
5425         security_ops = secondary_ops;
5426
5427         /* Unregister netfilter hooks. */
5428         selinux_nf_ip_exit();
5429
5430         /* Unregister selinuxfs. */
5431         exit_sel_fs();
5432
5433         return 0;
5434 }
5435 #endif
5436
5437