SAFE public projects git trees. - safe/jmp/linux-2.6/blob - security/selinux/hooks.c

   1 /*
   2  *  NSA Security-Enhanced Linux (SELinux) security module
   3  *
   4  *  This file contains the SELinux hook function implementations.
   5  *
   6  *  Authors:  Stephen Smalley, <sds@epoch.ncsc.mil>
   7  *            Chris Vance, <cvance@nai.com>
   8  *            Wayne Salamon, <wsalamon@nai.com>
   9  *            James Morris <jmorris@redhat.com>
  10  *
  11  *  Copyright (C) 2001,2002 Networks Associates Technology, Inc.
  12  *  Copyright (C) 2003-2008 Red Hat, Inc., James Morris <jmorris@redhat.com>
  13  *                                         Eric Paris <eparis@redhat.com>
  14  *  Copyright (C) 2004-2005 Trusted Computer Solutions, Inc.
  15  *                          <dgoeddel@trustedcs.com>
  16  *  Copyright (C) 2006, 2007 Hewlett-Packard Development Company, L.P.
  17  *              Paul Moore <paul.moore@hp.com>
  18  *  Copyright (C) 2007 Hitachi Software Engineering Co., Ltd.
  19  *                     Yuichi Nakamura <ynakam@hitachisoft.jp>
  20  *
  21  *      This program is free software; you can redistribute it and/or modify
  22  *      it under the terms of the GNU General Public License version 2,
  23  *      as published by the Free Software Foundation.
  24  */
  25
  26 #include <linux/init.h>
  27 #include <linux/kernel.h>
  28 #include <linux/tracehook.h>
  29 #include <linux/errno.h>
  30 #include <linux/sched.h>
  31 #include <linux/security.h>
  32 #include <linux/xattr.h>
  33 #include <linux/capability.h>
  34 #include <linux/unistd.h>
  35 #include <linux/mm.h>
  36 #include <linux/mman.h>
  37 #include <linux/slab.h>
  38 #include <linux/pagemap.h>
  39 #include <linux/swap.h>
  40 #include <linux/spinlock.h>
  41 #include <linux/syscalls.h>
  42 #include <linux/file.h>
  43 #include <linux/fdtable.h>
  44 #include <linux/namei.h>
  45 #include <linux/mount.h>
  46 #include <linux/proc_fs.h>
  47 #include <linux/netfilter_ipv4.h>
  48 #include <linux/netfilter_ipv6.h>
  49 #include <linux/tty.h>
  50 #include <net/icmp.h>
  51 #include <net/ip.h>             /* for local_port_range[] */
  52 #include <net/tcp.h>            /* struct or_callable used in sock_rcv_skb */
  53 #include <net/net_namespace.h>
  54 #include <net/netlabel.h>
  55 #include <linux/uaccess.h>
  56 #include <asm/ioctls.h>
  57 #include <asm/atomic.h>
  58 #include <linux/bitops.h>
  59 #include <linux/interrupt.h>
  60 #include <linux/netdevice.h>    /* for network interface checks */
  61 #include <linux/netlink.h>
  62 #include <linux/tcp.h>
  63 #include <linux/udp.h>
  64 #include <linux/dccp.h>
  65 #include <linux/quota.h>
  66 #include <linux/un.h>           /* for Unix socket types */
  67 #include <net/af_unix.h>        /* for Unix socket types */
  68 #include <linux/parser.h>
  69 #include <linux/nfs_mount.h>
  70 #include <net/ipv6.h>
  71 #include <linux/hugetlb.h>
  72 #include <linux/personality.h>
  73 #include <linux/sysctl.h>
  74 #include <linux/audit.h>
  75 #include <linux/string.h>
  76 #include <linux/selinux.h>
  77 #include <linux/mutex.h>
  78 #include <linux/posix-timers.h>
  79
  80 #include "avc.h"
  81 #include "objsec.h"
  82 #include "netif.h"
  83 #include "netnode.h"
  84 #include "netport.h"
  85 #include "xfrm.h"
  86 #include "netlabel.h"
  87 #include "audit.h"
  88
  89 #define XATTR_SELINUX_SUFFIX "selinux"
  90 #define XATTR_NAME_SELINUX XATTR_SECURITY_PREFIX XATTR_SELINUX_SUFFIX
  91
  92 #define NUM_SEL_MNT_OPTS 5
  93
  94 extern unsigned int policydb_loaded_version;
  95 extern int selinux_nlmsg_lookup(u16 sclass, u16 nlmsg_type, u32 *perm);
  96 extern int selinux_compat_net;
  97 extern struct security_operations *security_ops;
  98
  99 /* SECMARK reference count */
 100 atomic_t selinux_secmark_refcount = ATOMIC_INIT(0);
 101
 102 #ifdef CONFIG_SECURITY_SELINUX_DEVELOP
 103 int selinux_enforcing;
 104
 105 static int __init enforcing_setup(char *str)
 106 {
 107         unsigned long enforcing;
 108         if (!strict_strtoul(str, 0, &enforcing))
 109                 selinux_enforcing = enforcing ? 1 : 0;
 110         return 1;
 111 }
 112 __setup("enforcing=", enforcing_setup);
 113 #endif
 114
 115 #ifdef CONFIG_SECURITY_SELINUX_BOOTPARAM
 116 int selinux_enabled = CONFIG_SECURITY_SELINUX_BOOTPARAM_VALUE;
 117
 118 static int __init selinux_enabled_setup(char *str)
 119 {
 120         unsigned long enabled;
 121         if (!strict_strtoul(str, 0, &enabled))
 122                 selinux_enabled = enabled ? 1 : 0;
 123         return 1;
 124 }
 125 __setup("selinux=", selinux_enabled_setup);
 126 #else
 127 int selinux_enabled = 1;
 128 #endif
 129
 130
 131 /*
 132  * Minimal support for a secondary security module,
 133  * just to allow the use of the capability module.
 134  */
 135 static struct security_operations *secondary_ops;
 136
 137 /* Lists of inode and superblock security structures initialized
 138    before the policy was loaded. */
 139 static LIST_HEAD(superblock_security_head);
 140 static DEFINE_SPINLOCK(sb_security_lock);
 141
 142 static struct kmem_cache *sel_inode_cache;
 143
 144 /**
 145  * selinux_secmark_enabled - Check to see if SECMARK is currently enabled
 146  *
 147  * Description:
 148  * This function checks the SECMARK reference counter to see if any SECMARK
 149  * targets are currently configured, if the reference counter is greater than
 150  * zero SECMARK is considered to be enabled.  Returns true (1) if SECMARK is
 151  * enabled, false (0) if SECMARK is disabled.
 152  *
 153  */
 154 static int selinux_secmark_enabled(void)
 155 {
 156         return (atomic_read(&selinux_secmark_refcount) > 0);
 157 }
 158
 159 /*
 160  * initialise the security for the init task
 161  */
 162 static void cred_init_security(void)
 163 {
 164         struct cred *cred = (struct cred *) current->real_cred;
 165         struct task_security_struct *tsec;
 166
 167         tsec = kzalloc(sizeof(struct task_security_struct), GFP_KERNEL);
 168         if (!tsec)
 169                 panic("SELinux:  Failed to initialize initial task.\n");
 170
 171         tsec->osid = tsec->sid = SECINITSID_KERNEL;
 172         cred->security = tsec;
 173 }
 174
 175 /*
 176  * get the security ID of a set of credentials
 177  */
 178 static inline u32 cred_sid(const struct cred *cred)
 179 {
 180         const struct task_security_struct *tsec;
 181
 182         tsec = cred->security;
 183         return tsec->sid;
 184 }
 185
 186 /*
 187  * get the objective security ID of a task
 188  */
 189 static inline u32 task_sid(const struct task_struct *task)
 190 {
 191         u32 sid;
 192
 193         rcu_read_lock();
 194         sid = cred_sid(__task_cred(task));
 195         rcu_read_unlock();
 196         return sid;
 197 }
 198
 199 /*
 200  * get the subjective security ID of the current task
 201  */
 202 static inline u32 current_sid(void)
 203 {
 204         const struct task_security_struct *tsec = current_cred()->security;
 205
 206         return tsec->sid;
 207 }
 208
 209 /* Allocate and free functions for each kind of security blob. */
 210
 211 static int inode_alloc_security(struct inode *inode)
 212 {
 213         struct inode_security_struct *isec;
 214         u32 sid = current_sid();
 215
 216         isec = kmem_cache_zalloc(sel_inode_cache, GFP_NOFS);
 217         if (!isec)
 218                 return -ENOMEM;
 219
 220         mutex_init(&isec->lock);
 221         INIT_LIST_HEAD(&isec->list);
 222         isec->inode = inode;
 223         isec->sid = SECINITSID_UNLABELED;
 224         isec->sclass = SECCLASS_FILE;
 225         isec->task_sid = sid;
 226         inode->i_security = isec;
 227
 228         return 0;
 229 }
 230
 231 static void inode_free_security(struct inode *inode)
 232 {
 233         struct inode_security_struct *isec = inode->i_security;
 234         struct superblock_security_struct *sbsec = inode->i_sb->s_security;
 235
 236         spin_lock(&sbsec->isec_lock);
 237         if (!list_empty(&isec->list))
 238                 list_del_init(&isec->list);
 239         spin_unlock(&sbsec->isec_lock);
 240
 241         inode->i_security = NULL;
 242         kmem_cache_free(sel_inode_cache, isec);
 243 }
 244
 245 static int file_alloc_security(struct file *file)
 246 {
 247         struct file_security_struct *fsec;
 248         u32 sid = current_sid();
 249
 250         fsec = kzalloc(sizeof(struct file_security_struct), GFP_KERNEL);
 251         if (!fsec)
 252                 return -ENOMEM;
 253
 254         fsec->sid = sid;
 255         fsec->fown_sid = sid;
 256         file->f_security = fsec;
 257
 258         return 0;
 259 }
 260
 261 static void file_free_security(struct file *file)
 262 {
 263         struct file_security_struct *fsec = file->f_security;
 264         file->f_security = NULL;
 265         kfree(fsec);
 266 }
 267
 268 static int superblock_alloc_security(struct super_block *sb)
 269 {
 270         struct superblock_security_struct *sbsec;
 271
 272         sbsec = kzalloc(sizeof(struct superblock_security_struct), GFP_KERNEL);
 273         if (!sbsec)
 274                 return -ENOMEM;
 275
 276         mutex_init(&sbsec->lock);
 277         INIT_LIST_HEAD(&sbsec->list);
 278         INIT_LIST_HEAD(&sbsec->isec_head);
 279         spin_lock_init(&sbsec->isec_lock);
 280         sbsec->sb = sb;
 281         sbsec->sid = SECINITSID_UNLABELED;
 282         sbsec->def_sid = SECINITSID_FILE;
 283         sbsec->mntpoint_sid = SECINITSID_UNLABELED;
 284         sb->s_security = sbsec;
 285
 286         return 0;
 287 }
 288
 289 static void superblock_free_security(struct super_block *sb)
 290 {
 291         struct superblock_security_struct *sbsec = sb->s_security;
 292
 293         spin_lock(&sb_security_lock);
 294         if (!list_empty(&sbsec->list))
 295                 list_del_init(&sbsec->list);
 296         spin_unlock(&sb_security_lock);
 297
 298         sb->s_security = NULL;
 299         kfree(sbsec);
 300 }
 301
 302 static int sk_alloc_security(struct sock *sk, int family, gfp_t priority)
 303 {
 304         struct sk_security_struct *ssec;
 305
 306         ssec = kzalloc(sizeof(*ssec), priority);
 307         if (!ssec)
 308                 return -ENOMEM;
 309
 310         ssec->peer_sid = SECINITSID_UNLABELED;
 311         ssec->sid = SECINITSID_UNLABELED;
 312         sk->sk_security = ssec;
 313
 314         selinux_netlbl_sk_security_reset(ssec, family);
 315
 316         return 0;
 317 }
 318
 319 static void sk_free_security(struct sock *sk)
 320 {
 321         struct sk_security_struct *ssec = sk->sk_security;
 322
 323         sk->sk_security = NULL;
 324         selinux_netlbl_sk_security_free(ssec);
 325         kfree(ssec);
 326 }
 327
 328 /* The security server must be initialized before
 329    any labeling or access decisions can be provided. */
 330 extern int ss_initialized;
 331
 332 /* The file system's label must be initialized prior to use. */
 333
 334 static char *labeling_behaviors[6] = {
 335         "uses xattr",
 336         "uses transition SIDs",
 337         "uses task SIDs",
 338         "uses genfs_contexts",
 339         "not configured for labeling",
 340         "uses mountpoint labeling",
 341 };
 342
 343 static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dentry);
 344
 345 static inline int inode_doinit(struct inode *inode)
 346 {
 347         return inode_doinit_with_dentry(inode, NULL);
 348 }
 349
 350 enum {
 351         Opt_error = -1,
 352         Opt_context = 1,
 353         Opt_fscontext = 2,
 354         Opt_defcontext = 3,
 355         Opt_rootcontext = 4,
 356         Opt_labelsupport = 5,
 357 };
 358
 359 static const match_table_t tokens = {
 360         {Opt_context, CONTEXT_STR "%s"},
 361         {Opt_fscontext, FSCONTEXT_STR "%s"},
 362         {Opt_defcontext, DEFCONTEXT_STR "%s"},
 363         {Opt_rootcontext, ROOTCONTEXT_STR "%s"},
 364         {Opt_labelsupport, LABELSUPP_STR},
 365         {Opt_error, NULL},
 366 };
 367
 368 #define SEL_MOUNT_FAIL_MSG "SELinux:  duplicate or incompatible mount options\n"
 369
 370 static int may_context_mount_sb_relabel(u32 sid,
 371                         struct superblock_security_struct *sbsec,
 372                         const struct cred *cred)
 373 {
 374         const struct task_security_struct *tsec = cred->security;
 375         int rc;
 376
 377         rc = avc_has_perm(tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM,
 378                           FILESYSTEM__RELABELFROM, NULL);
 379         if (rc)
 380                 return rc;
 381
 382         rc = avc_has_perm(tsec->sid, sid, SECCLASS_FILESYSTEM,
 383                           FILESYSTEM__RELABELTO, NULL);
 384         return rc;
 385 }
 386
 387 static int may_context_mount_inode_relabel(u32 sid,
 388                         struct superblock_security_struct *sbsec,
 389                         const struct cred *cred)
 390 {
 391         const struct task_security_struct *tsec = cred->security;
 392         int rc;
 393         rc = avc_has_perm(tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM,
 394                           FILESYSTEM__RELABELFROM, NULL);
 395         if (rc)
 396                 return rc;
 397
 398         rc = avc_has_perm(sid, sbsec->sid, SECCLASS_FILESYSTEM,
 399                           FILESYSTEM__ASSOCIATE, NULL);
 400         return rc;
 401 }
 402
 403 static int sb_finish_set_opts(struct super_block *sb)
 404 {
 405         struct superblock_security_struct *sbsec = sb->s_security;
 406         struct dentry *root = sb->s_root;
 407         struct inode *root_inode = root->d_inode;
 408         int rc = 0;
 409
 410         if (sbsec->behavior == SECURITY_FS_USE_XATTR) {
 411                 /* Make sure that the xattr handler exists and that no
 412                    error other than -ENODATA is returned by getxattr on
 413                    the root directory.  -ENODATA is ok, as this may be
 414                    the first boot of the SELinux kernel before we have
 415                    assigned xattr values to the filesystem. */
 416                 if (!root_inode->i_op->getxattr) {
 417                         printk(KERN_WARNING "SELinux: (dev %s, type %s) has no "
 418                                "xattr support\n", sb->s_id, sb->s_type->name);
 419                         rc = -EOPNOTSUPP;
 420                         goto out;
 421                 }
 422                 rc = root_inode->i_op->getxattr(root, XATTR_NAME_SELINUX, NULL, 0);
 423                 if (rc < 0 && rc != -ENODATA) {
 424                         if (rc == -EOPNOTSUPP)
 425                                 printk(KERN_WARNING "SELinux: (dev %s, type "
 426                                        "%s) has no security xattr handler\n",
 427                                        sb->s_id, sb->s_type->name);
 428                         else
 429                                 printk(KERN_WARNING "SELinux: (dev %s, type "
 430                                        "%s) getxattr errno %d\n", sb->s_id,
 431                                        sb->s_type->name, -rc);
 432                         goto out;
 433                 }
 434         }
 435
 436         sbsec->flags |= (SE_SBINITIALIZED | SE_SBLABELSUPP);
 437
 438         if (sbsec->behavior > ARRAY_SIZE(labeling_behaviors))
 439                 printk(KERN_ERR "SELinux: initialized (dev %s, type %s), unknown behavior\n",
 440                        sb->s_id, sb->s_type->name);
 441         else
 442                 printk(KERN_DEBUG "SELinux: initialized (dev %s, type %s), %s\n",
 443                        sb->s_id, sb->s_type->name,
 444                        labeling_behaviors[sbsec->behavior-1]);
 445
 446         if (sbsec->behavior == SECURITY_FS_USE_GENFS ||
 447             sbsec->behavior == SECURITY_FS_USE_MNTPOINT ||
 448             sbsec->behavior == SECURITY_FS_USE_NONE ||
 449             sbsec->behavior > ARRAY_SIZE(labeling_behaviors))
 450                 sbsec->flags &= ~SE_SBLABELSUPP;
 451
 452         /* Initialize the root inode. */
 453         rc = inode_doinit_with_dentry(root_inode, root);
 454
 455         /* Initialize any other inodes associated with the superblock, e.g.
 456            inodes created prior to initial policy load or inodes created
 457            during get_sb by a pseudo filesystem that directly
 458            populates itself. */
 459         spin_lock(&sbsec->isec_lock);
 460 next_inode:
 461         if (!list_empty(&sbsec->isec_head)) {
 462                 struct inode_security_struct *isec =
 463                                 list_entry(sbsec->isec_head.next,
 464                                            struct inode_security_struct, list);
 465                 struct inode *inode = isec->inode;
 466                 spin_unlock(&sbsec->isec_lock);
 467                 inode = igrab(inode);
 468                 if (inode) {
 469                         if (!IS_PRIVATE(inode))
 470                                 inode_doinit(inode);
 471                         iput(inode);
 472                 }
 473                 spin_lock(&sbsec->isec_lock);
 474                 list_del_init(&isec->list);
 475                 goto next_inode;
 476         }
 477         spin_unlock(&sbsec->isec_lock);
 478 out:
 479         return rc;
 480 }
 481
 482 /*
 483  * This function should allow an FS to ask what it's mount security
 484  * options were so it can use those later for submounts, displaying
 485  * mount options, or whatever.
 486  */
 487 static int selinux_get_mnt_opts(const struct super_block *sb,
 488                                 struct security_mnt_opts *opts)
 489 {
 490         int rc = 0, i;
 491         struct superblock_security_struct *sbsec = sb->s_security;
 492         char *context = NULL;
 493         u32 len;
 494         char tmp;
 495
 496         security_init_mnt_opts(opts);
 497
 498         if (!(sbsec->flags & SE_SBINITIALIZED))
 499                 return -EINVAL;
 500
 501         if (!ss_initialized)
 502                 return -EINVAL;
 503
 504         tmp = sbsec->flags & SE_MNTMASK;
 505         /* count the number of mount options for this sb */
 506         for (i = 0; i < 8; i++) {
 507                 if (tmp & 0x01)
 508                         opts->num_mnt_opts++;
 509                 tmp >>= 1;
 510         }
 511         /* Check if the Label support flag is set */
 512         if (sbsec->flags & SE_SBLABELSUPP)
 513                 opts->num_mnt_opts++;
 514
 515         opts->mnt_opts = kcalloc(opts->num_mnt_opts, sizeof(char *), GFP_ATOMIC);
 516         if (!opts->mnt_opts) {
 517                 rc = -ENOMEM;
 518                 goto out_free;
 519         }
 520
 521         opts->mnt_opts_flags = kcalloc(opts->num_mnt_opts, sizeof(int), GFP_ATOMIC);
 522         if (!opts->mnt_opts_flags) {
 523                 rc = -ENOMEM;
 524                 goto out_free;
 525         }
 526
 527         i = 0;
 528         if (sbsec->flags & FSCONTEXT_MNT) {
 529                 rc = security_sid_to_context(sbsec->sid, &context, &len);
 530                 if (rc)
 531                         goto out_free;
 532                 opts->mnt_opts[i] = context;
 533                 opts->mnt_opts_flags[i++] = FSCONTEXT_MNT;
 534         }
 535         if (sbsec->flags & CONTEXT_MNT) {
 536                 rc = security_sid_to_context(sbsec->mntpoint_sid, &context, &len);
 537                 if (rc)
 538                         goto out_free;
 539                 opts->mnt_opts[i] = context;
 540                 opts->mnt_opts_flags[i++] = CONTEXT_MNT;
 541         }
 542         if (sbsec->flags & DEFCONTEXT_MNT) {
 543                 rc = security_sid_to_context(sbsec->def_sid, &context, &len);
 544                 if (rc)
 545                         goto out_free;
 546                 opts->mnt_opts[i] = context;
 547                 opts->mnt_opts_flags[i++] = DEFCONTEXT_MNT;
 548         }
 549         if (sbsec->flags & ROOTCONTEXT_MNT) {
 550                 struct inode *root = sbsec->sb->s_root->d_inode;
 551                 struct inode_security_struct *isec = root->i_security;
 552
 553                 rc = security_sid_to_context(isec->sid, &context, &len);
 554                 if (rc)
 555                         goto out_free;
 556                 opts->mnt_opts[i] = context;
 557                 opts->mnt_opts_flags[i++] = ROOTCONTEXT_MNT;
 558         }
 559         if (sbsec->flags & SE_SBLABELSUPP) {
 560                 opts->mnt_opts[i] = NULL;
 561                 opts->mnt_opts_flags[i++] = SE_SBLABELSUPP;
 562         }
 563
 564         BUG_ON(i != opts->num_mnt_opts);
 565
 566         return 0;
 567
 568 out_free:
 569         security_free_mnt_opts(opts);
 570         return rc;
 571 }
 572
 573 static int bad_option(struct superblock_security_struct *sbsec, char flag,
 574                       u32 old_sid, u32 new_sid)
 575 {
 576         char mnt_flags = sbsec->flags & SE_MNTMASK;
 577
 578         /* check if the old mount command had the same options */
 579         if (sbsec->flags & SE_SBINITIALIZED)
 580                 if (!(sbsec->flags & flag) ||
 581                     (old_sid != new_sid))
 582                         return 1;
 583
 584         /* check if we were passed the same options twice,
 585          * aka someone passed context=a,context=b
 586          */
 587         if (!(sbsec->flags & SE_SBINITIALIZED))
 588                 if (mnt_flags & flag)
 589                         return 1;
 590         return 0;
 591 }
 592
 593 /*
 594  * Allow filesystems with binary mount data to explicitly set mount point
 595  * labeling information.
 596  */
 597 static int selinux_set_mnt_opts(struct super_block *sb,
 598                                 struct security_mnt_opts *opts)
 599 {
 600         const struct cred *cred = current_cred();
 601         int rc = 0, i;
 602         struct superblock_security_struct *sbsec = sb->s_security;
 603         const char *name = sb->s_type->name;
 604         struct inode *inode = sbsec->sb->s_root->d_inode;
 605         struct inode_security_struct *root_isec = inode->i_security;
 606         u32 fscontext_sid = 0, context_sid = 0, rootcontext_sid = 0;
 607         u32 defcontext_sid = 0;
 608         char **mount_options = opts->mnt_opts;
 609         int *flags = opts->mnt_opts_flags;
 610         int num_opts = opts->num_mnt_opts;
 611
 612         mutex_lock(&sbsec->lock);
 613
 614         if (!ss_initialized) {
 615                 if (!num_opts) {
 616                         /* Defer initialization until selinux_complete_init,
 617                            after the initial policy is loaded and the security
 618                            server is ready to handle calls. */
 619                         spin_lock(&sb_security_lock);
 620                         if (list_empty(&sbsec->list))
 621                                 list_add(&sbsec->list, &superblock_security_head);
 622                         spin_unlock(&sb_security_lock);
 623                         goto out;
 624                 }
 625                 rc = -EINVAL;
 626                 printk(KERN_WARNING "SELinux: Unable to set superblock options "
 627                         "before the security server is initialized\n");
 628                 goto out;
 629         }
 630
 631         /*
 632          * Binary mount data FS will come through this function twice.  Once
 633          * from an explicit call and once from the generic calls from the vfs.
 634          * Since the generic VFS calls will not contain any security mount data
 635          * we need to skip the double mount verification.
 636          *
 637          * This does open a hole in which we will not notice if the first
 638          * mount using this sb set explict options and a second mount using
 639          * this sb does not set any security options.  (The first options
 640          * will be used for both mounts)
 641          */
 642         if ((sbsec->flags & SE_SBINITIALIZED) && (sb->s_type->fs_flags & FS_BINARY_MOUNTDATA)
 643             && (num_opts == 0))
 644                 goto out;
 645
 646         /*
 647          * parse the mount options, check if they are valid sids.
 648          * also check if someone is trying to mount the same sb more
 649          * than once with different security options.
 650          */
 651         for (i = 0; i < num_opts; i++) {
 652                 u32 sid;
 653
 654                 if (flags[i] == SE_SBLABELSUPP)
 655                         continue;
 656                 rc = security_context_to_sid(mount_options[i],
 657                                              strlen(mount_options[i]), &sid);
 658                 if (rc) {
 659                         printk(KERN_WARNING "SELinux: security_context_to_sid"
 660                                "(%s) failed for (dev %s, type %s) errno=%d\n",
 661                                mount_options[i], sb->s_id, name, rc);
 662                         goto out;
 663                 }
 664                 switch (flags[i]) {
 665                 case FSCONTEXT_MNT:
 666                         fscontext_sid = sid;
 667
 668                         if (bad_option(sbsec, FSCONTEXT_MNT, sbsec->sid,
 669                                         fscontext_sid))
 670                                 goto out_double_mount;
 671
 672                         sbsec->flags |= FSCONTEXT_MNT;
 673                         break;
 674                 case CONTEXT_MNT:
 675                         context_sid = sid;
 676
 677                         if (bad_option(sbsec, CONTEXT_MNT, sbsec->mntpoint_sid,
 678                                         context_sid))
 679                                 goto out_double_mount;
 680
 681                         sbsec->flags |= CONTEXT_MNT;
 682                         break;
 683                 case ROOTCONTEXT_MNT:
 684                         rootcontext_sid = sid;
 685
 686                         if (bad_option(sbsec, ROOTCONTEXT_MNT, root_isec->sid,
 687                                         rootcontext_sid))
 688                                 goto out_double_mount;
 689
 690                         sbsec->flags |= ROOTCONTEXT_MNT;
 691
 692                         break;
 693                 case DEFCONTEXT_MNT:
 694                         defcontext_sid = sid;
 695
 696                         if (bad_option(sbsec, DEFCONTEXT_MNT, sbsec->def_sid,
 697                                         defcontext_sid))
 698                                 goto out_double_mount;
 699
 700                         sbsec->flags |= DEFCONTEXT_MNT;
 701
 702                         break;
 703                 default:
 704                         rc = -EINVAL;
 705                         goto out;
 706                 }
 707         }
 708
 709         if (sbsec->flags & SE_SBINITIALIZED) {
 710                 /* previously mounted with options, but not on this attempt? */
 711                 if ((sbsec->flags & SE_MNTMASK) && !num_opts)
 712                         goto out_double_mount;
 713                 rc = 0;
 714                 goto out;
 715         }
 716
 717         if (strcmp(sb->s_type->name, "proc") == 0)
 718                 sbsec->flags |= SE_SBPROC;
 719
 720         /* Determine the labeling behavior to use for this filesystem type. */
 721         rc = security_fs_use((sbsec->flags & SE_SBPROC) ? "proc" : sb->s_type->name, &sbsec->behavior, &sbsec->sid);
 722         if (rc) {
 723                 printk(KERN_WARNING "%s: security_fs_use(%s) returned %d\n",
 724                        __func__, sb->s_type->name, rc);
 725                 goto out;
 726         }
 727
 728         /* sets the context of the superblock for the fs being mounted. */
 729         if (fscontext_sid) {
 730                 rc = may_context_mount_sb_relabel(fscontext_sid, sbsec, cred);
 731                 if (rc)
 732                         goto out;
 733
 734                 sbsec->sid = fscontext_sid;
 735         }
 736
 737         /*
 738          * Switch to using mount point labeling behavior.
 739          * sets the label used on all file below the mountpoint, and will set
 740          * the superblock context if not already set.
 741          */
 742         if (context_sid) {
 743                 if (!fscontext_sid) {
 744                         rc = may_context_mount_sb_relabel(context_sid, sbsec,
 745                                                           cred);
 746                         if (rc)
 747                                 goto out;
 748                         sbsec->sid = context_sid;
 749                 } else {
 750                         rc = may_context_mount_inode_relabel(context_sid, sbsec,
 751                                                              cred);
 752                         if (rc)
 753                                 goto out;
 754                 }
 755                 if (!rootcontext_sid)
 756                         rootcontext_sid = context_sid;
 757
 758                 sbsec->mntpoint_sid = context_sid;
 759                 sbsec->behavior = SECURITY_FS_USE_MNTPOINT;
 760         }
 761
 762         if (rootcontext_sid) {
 763                 rc = may_context_mount_inode_relabel(rootcontext_sid, sbsec,
 764                                                      cred);
 765                 if (rc)
 766                         goto out;
 767
 768                 root_isec->sid = rootcontext_sid;
 769                 root_isec->initialized = 1;
 770         }
 771
 772         if (defcontext_sid) {
 773                 if (sbsec->behavior != SECURITY_FS_USE_XATTR) {
 774                         rc = -EINVAL;
 775                         printk(KERN_WARNING "SELinux: defcontext option is "
 776                                "invalid for this filesystem type\n");
 777                         goto out;
 778                 }
 779
 780                 if (defcontext_sid != sbsec->def_sid) {
 781                         rc = may_context_mount_inode_relabel(defcontext_sid,
 782                                                              sbsec, cred);
 783                         if (rc)
 784                                 goto out;
 785                 }
 786
 787                 sbsec->def_sid = defcontext_sid;
 788         }
 789
 790         rc = sb_finish_set_opts(sb);
 791 out:
 792         mutex_unlock(&sbsec->lock);
 793         return rc;
 794 out_double_mount:
 795         rc = -EINVAL;
 796         printk(KERN_WARNING "SELinux: mount invalid.  Same superblock, different "
 797                "security settings for (dev %s, type %s)\n", sb->s_id, name);
 798         goto out;
 799 }
 800
 801 static void selinux_sb_clone_mnt_opts(const struct super_block *oldsb,
 802                                         struct super_block *newsb)
 803 {
 804         const struct superblock_security_struct *oldsbsec = oldsb->s_security;
 805         struct superblock_security_struct *newsbsec = newsb->s_security;
 806
 807         int set_fscontext =     (oldsbsec->flags & FSCONTEXT_MNT);
 808         int set_context =       (oldsbsec->flags & CONTEXT_MNT);
 809         int set_rootcontext =   (oldsbsec->flags & ROOTCONTEXT_MNT);
 810
 811         /*
 812          * if the parent was able to be mounted it clearly had no special lsm
 813          * mount options.  thus we can safely put this sb on the list and deal
 814          * with it later
 815          */
 816         if (!ss_initialized) {
 817                 spin_lock(&sb_security_lock);
 818                 if (list_empty(&newsbsec->list))
 819                         list_add(&newsbsec->list, &superblock_security_head);
 820                 spin_unlock(&sb_security_lock);
 821                 return;
 822         }
 823
 824         /* how can we clone if the old one wasn't set up?? */
 825         BUG_ON(!(oldsbsec->flags & SE_SBINITIALIZED));
 826
 827         /* if fs is reusing a sb, just let its options stand... */
 828         if (newsbsec->flags & SE_SBINITIALIZED)
 829                 return;
 830
 831         mutex_lock(&newsbsec->lock);
 832
 833         newsbsec->flags = oldsbsec->flags;
 834
 835         newsbsec->sid = oldsbsec->sid;
 836         newsbsec->def_sid = oldsbsec->def_sid;
 837         newsbsec->behavior = oldsbsec->behavior;
 838
 839         if (set_context) {
 840                 u32 sid = oldsbsec->mntpoint_sid;
 841
 842                 if (!set_fscontext)
 843                         newsbsec->sid = sid;
 844                 if (!set_rootcontext) {
 845                         struct inode *newinode = newsb->s_root->d_inode;
 846                         struct inode_security_struct *newisec = newinode->i_security;
 847                         newisec->sid = sid;
 848                 }
 849                 newsbsec->mntpoint_sid = sid;
 850         }
 851         if (set_rootcontext) {
 852                 const struct inode *oldinode = oldsb->s_root->d_inode;
 853                 const struct inode_security_struct *oldisec = oldinode->i_security;
 854                 struct inode *newinode = newsb->s_root->d_inode;
 855                 struct inode_security_struct *newisec = newinode->i_security;
 856
 857                 newisec->sid = oldisec->sid;
 858         }
 859
 860         sb_finish_set_opts(newsb);
 861         mutex_unlock(&newsbsec->lock);
 862 }
 863
 864 static int selinux_parse_opts_str(char *options,
 865                                   struct security_mnt_opts *opts)
 866 {
 867         char *p;
 868         char *context = NULL, *defcontext = NULL;
 869         char *fscontext = NULL, *rootcontext = NULL;
 870         int rc, num_mnt_opts = 0;
 871
 872         opts->num_mnt_opts = 0;
 873
 874         /* Standard string-based options. */
 875         while ((p = strsep(&options, "|")) != NULL) {
 876                 int token;
 877                 substring_t args[MAX_OPT_ARGS];
 878
 879                 if (!*p)
 880                         continue;
 881
 882                 token = match_token(p, tokens, args);
 883
 884                 switch (token) {
 885                 case Opt_context:
 886                         if (context || defcontext) {
 887                                 rc = -EINVAL;
 888                                 printk(KERN_WARNING SEL_MOUNT_FAIL_MSG);
 889                                 goto out_err;
 890                         }
 891                         context = match_strdup(&args[0]);
 892                         if (!context) {
 893                                 rc = -ENOMEM;
 894                                 goto out_err;
 895                         }
 896                         break;
 897
 898                 case Opt_fscontext:
 899                         if (fscontext) {
 900                                 rc = -EINVAL;
 901                                 printk(KERN_WARNING SEL_MOUNT_FAIL_MSG);
 902                                 goto out_err;
 903                         }
 904                         fscontext = match_strdup(&args[0]);
 905                         if (!fscontext) {
 906                                 rc = -ENOMEM;
 907                                 goto out_err;
 908                         }
 909                         break;
 910
 911                 case Opt_rootcontext:
 912                         if (rootcontext) {
 913                                 rc = -EINVAL;
 914                                 printk(KERN_WARNING SEL_MOUNT_FAIL_MSG);
 915                                 goto out_err;
 916                         }
 917                         rootcontext = match_strdup(&args[0]);
 918                         if (!rootcontext) {
 919                                 rc = -ENOMEM;
 920                                 goto out_err;
 921                         }
 922                         break;
 923
 924                 case Opt_defcontext:
 925                         if (context || defcontext) {
 926                                 rc = -EINVAL;
 927                                 printk(KERN_WARNING SEL_MOUNT_FAIL_MSG);
 928                                 goto out_err;
 929                         }
 930                         defcontext = match_strdup(&args[0]);
 931                         if (!defcontext) {
 932                                 rc = -ENOMEM;
 933                                 goto out_err;
 934                         }
 935                         break;
 936                 case Opt_labelsupport:
 937                         break;
 938                 default:
 939                         rc = -EINVAL;
 940                         printk(KERN_WARNING "SELinux:  unknown mount option\n");
 941                         goto out_err;
 942
 943                 }
 944         }
 945
 946         rc = -ENOMEM;
 947         opts->mnt_opts = kcalloc(NUM_SEL_MNT_OPTS, sizeof(char *), GFP_ATOMIC);
 948         if (!opts->mnt_opts)
 949                 goto out_err;
 950
 951         opts->mnt_opts_flags = kcalloc(NUM_SEL_MNT_OPTS, sizeof(int), GFP_ATOMIC);
 952         if (!opts->mnt_opts_flags) {
 953                 kfree(opts->mnt_opts);
 954                 goto out_err;
 955         }
 956
 957         if (fscontext) {
 958                 opts->mnt_opts[num_mnt_opts] = fscontext;
 959                 opts->mnt_opts_flags[num_mnt_opts++] = FSCONTEXT_MNT;
 960         }
 961         if (context) {
 962                 opts->mnt_opts[num_mnt_opts] = context;
 963                 opts->mnt_opts_flags[num_mnt_opts++] = CONTEXT_MNT;
 964         }
 965         if (rootcontext) {
 966                 opts->mnt_opts[num_mnt_opts] = rootcontext;
 967                 opts->mnt_opts_flags[num_mnt_opts++] = ROOTCONTEXT_MNT;
 968         }
 969         if (defcontext) {
 970                 opts->mnt_opts[num_mnt_opts] = defcontext;
 971                 opts->mnt_opts_flags[num_mnt_opts++] = DEFCONTEXT_MNT;
 972         }
 973
 974         opts->num_mnt_opts = num_mnt_opts;
 975         return 0;
 976
 977 out_err:
 978         kfree(context);
 979         kfree(defcontext);
 980         kfree(fscontext);
 981         kfree(rootcontext);
 982         return rc;
 983 }
 984 /*
 985  * string mount options parsing and call set the sbsec
 986  */
 987 static int superblock_doinit(struct super_block *sb, void *data)
 988 {
 989         int rc = 0;
 990         char *options = data;
 991         struct security_mnt_opts opts;
 992
 993         security_init_mnt_opts(&opts);
 994
 995         if (!data)
 996                 goto out;
 997
 998         BUG_ON(sb->s_type->fs_flags & FS_BINARY_MOUNTDATA);
 999
1000         rc = selinux_parse_opts_str(options, &opts);
1001         if (rc)
1002                 goto out_err;
1003
1004 out:
1005         rc = selinux_set_mnt_opts(sb, &opts);
1006
1007 out_err:
1008         security_free_mnt_opts(&opts);
1009         return rc;
1010 }
1011
1012 static void selinux_write_opts(struct seq_file *m,
1013                                struct security_mnt_opts *opts)
1014 {
1015         int i;
1016         char *prefix;
1017
1018         for (i = 0; i < opts->num_mnt_opts; i++) {
1019                 char *has_comma;
1020
1021                 if (opts->mnt_opts[i])
1022                         has_comma = strchr(opts->mnt_opts[i], ',');
1023                 else
1024                         has_comma = NULL;
1025
1026                 switch (opts->mnt_opts_flags[i]) {
1027                 case CONTEXT_MNT:
1028                         prefix = CONTEXT_STR;
1029                         break;
1030                 case FSCONTEXT_MNT:
1031                         prefix = FSCONTEXT_STR;
1032                         break;
1033                 case ROOTCONTEXT_MNT:
1034                         prefix = ROOTCONTEXT_STR;
1035                         break;
1036                 case DEFCONTEXT_MNT:
1037                         prefix = DEFCONTEXT_STR;
1038                         break;
1039                 case SE_SBLABELSUPP:
1040                         seq_putc(m, ',');
1041                         seq_puts(m, LABELSUPP_STR);
1042                         continue;
1043                 default:
1044                         BUG();
1045                 };
1046                 /* we need a comma before each option */
1047                 seq_putc(m, ',');
1048                 seq_puts(m, prefix);
1049                 if (has_comma)
1050                         seq_putc(m, '\"');
1051                 seq_puts(m, opts->mnt_opts[i]);
1052                 if (has_comma)
1053                         seq_putc(m, '\"');
1054         }
1055 }
1056
1057 static int selinux_sb_show_options(struct seq_file *m, struct super_block *sb)
1058 {
1059         struct security_mnt_opts opts;
1060         int rc;
1061
1062         rc = selinux_get_mnt_opts(sb, &opts);
1063         if (rc) {
1064                 /* before policy load we may get EINVAL, don't show anything */
1065                 if (rc == -EINVAL)
1066                         rc = 0;
1067                 return rc;
1068         }
1069
1070         selinux_write_opts(m, &opts);
1071
1072         security_free_mnt_opts(&opts);
1073
1074         return rc;
1075 }
1076
1077 static inline u16 inode_mode_to_security_class(umode_t mode)
1078 {
1079         switch (mode & S_IFMT) {
1080         case S_IFSOCK:
1081                 return SECCLASS_SOCK_FILE;
1082         case S_IFLNK:
1083                 return SECCLASS_LNK_FILE;
1084         case S_IFREG:
1085                 return SECCLASS_FILE;
1086         case S_IFBLK:
1087                 return SECCLASS_BLK_FILE;
1088         case S_IFDIR:
1089                 return SECCLASS_DIR;
1090         case S_IFCHR:
1091                 return SECCLASS_CHR_FILE;
1092         case S_IFIFO:
1093                 return SECCLASS_FIFO_FILE;
1094
1095         }
1096
1097         return SECCLASS_FILE;
1098 }
1099
1100 static inline int default_protocol_stream(int protocol)
1101 {
1102         return (protocol == IPPROTO_IP || protocol == IPPROTO_TCP);
1103 }
1104
1105 static inline int default_protocol_dgram(int protocol)
1106 {
1107         return (protocol == IPPROTO_IP || protocol == IPPROTO_UDP);
1108 }
1109
1110 static inline u16 socket_type_to_security_class(int family, int type, int protocol)
1111 {
1112         switch (family) {
1113         case PF_UNIX:
1114                 switch (type) {
1115                 case SOCK_STREAM:
1116                 case SOCK_SEQPACKET:
1117                         return SECCLASS_UNIX_STREAM_SOCKET;
1118                 case SOCK_DGRAM:
1119                         return SECCLASS_UNIX_DGRAM_SOCKET;
1120                 }
1121                 break;
1122         case PF_INET:
1123         case PF_INET6:
1124                 switch (type) {
1125                 case SOCK_STREAM:
1126                         if (default_protocol_stream(protocol))
1127                                 return SECCLASS_TCP_SOCKET;
1128                         else
1129                                 return SECCLASS_RAWIP_SOCKET;
1130                 case SOCK_DGRAM:
1131                         if (default_protocol_dgram(protocol))
1132                                 return SECCLASS_UDP_SOCKET;
1133                         else
1134                                 return SECCLASS_RAWIP_SOCKET;
1135                 case SOCK_DCCP:
1136                         return SECCLASS_DCCP_SOCKET;
1137                 default:
1138                         return SECCLASS_RAWIP_SOCKET;
1139                 }
1140                 break;
1141         case PF_NETLINK:
1142                 switch (protocol) {
1143                 case NETLINK_ROUTE:
1144                         return SECCLASS_NETLINK_ROUTE_SOCKET;
1145                 case NETLINK_FIREWALL:
1146                         return SECCLASS_NETLINK_FIREWALL_SOCKET;
1147                 case NETLINK_INET_DIAG:
1148                         return SECCLASS_NETLINK_TCPDIAG_SOCKET;
1149                 case NETLINK_NFLOG:
1150                         return SECCLASS_NETLINK_NFLOG_SOCKET;
1151                 case NETLINK_XFRM:
1152                         return SECCLASS_NETLINK_XFRM_SOCKET;
1153                 case NETLINK_SELINUX:
1154                         return SECCLASS_NETLINK_SELINUX_SOCKET;
1155                 case NETLINK_AUDIT:
1156                         return SECCLASS_NETLINK_AUDIT_SOCKET;
1157                 case NETLINK_IP6_FW:
1158                         return SECCLASS_NETLINK_IP6FW_SOCKET;
1159                 case NETLINK_DNRTMSG:
1160                         return SECCLASS_NETLINK_DNRT_SOCKET;
1161                 case NETLINK_KOBJECT_UEVENT:
1162                         return SECCLASS_NETLINK_KOBJECT_UEVENT_SOCKET;
1163                 default:
1164                         return SECCLASS_NETLINK_SOCKET;
1165                 }
1166         case PF_PACKET:
1167                 return SECCLASS_PACKET_SOCKET;
1168         case PF_KEY:
1169                 return SECCLASS_KEY_SOCKET;
1170         case PF_APPLETALK:
1171                 return SECCLASS_APPLETALK_SOCKET;
1172         }
1173
1174         return SECCLASS_SOCKET;
1175 }
1176
1177 #ifdef CONFIG_PROC_FS
1178 static int selinux_proc_get_sid(struct proc_dir_entry *de,
1179                                 u16 tclass,
1180                                 u32 *sid)
1181 {
1182         int buflen, rc;
1183         char *buffer, *path, *end;
1184
1185         buffer = (char *)__get_free_page(GFP_KERNEL);
1186         if (!buffer)
1187                 return -ENOMEM;
1188
1189         buflen = PAGE_SIZE;
1190         end = buffer+buflen;
1191         *--end = '\0';
1192         buflen--;
1193         path = end-1;
1194         *path = '/';
1195         while (de && de != de->parent) {
1196                 buflen -= de->namelen + 1;
1197                 if (buflen < 0)
1198                         break;
1199                 end -= de->namelen;
1200                 memcpy(end, de->name, de->namelen);
1201                 *--end = '/';
1202                 path = end;
1203                 de = de->parent;
1204         }
1205         rc = security_genfs_sid("proc", path, tclass, sid);
1206         free_page((unsigned long)buffer);
1207         return rc;
1208 }
1209 #else
1210 static int selinux_proc_get_sid(struct proc_dir_entry *de,
1211                                 u16 tclass,
1212                                 u32 *sid)
1213 {
1214         return -EINVAL;
1215 }
1216 #endif
1217
1218 /* The inode's security attributes must be initialized before first use. */
1219 static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dentry)
1220 {
1221         struct superblock_security_struct *sbsec = NULL;
1222         struct inode_security_struct *isec = inode->i_security;
1223         u32 sid;
1224         struct dentry *dentry;
1225 #define INITCONTEXTLEN 255
1226         char *context = NULL;
1227         unsigned len = 0;
1228         int rc = 0;
1229
1230         if (isec->initialized)
1231                 goto out;
1232
1233         mutex_lock(&isec->lock);
1234         if (isec->initialized)
1235                 goto out_unlock;
1236
1237         sbsec = inode->i_sb->s_security;
1238         if (!(sbsec->flags & SE_SBINITIALIZED)) {
1239                 /* Defer initialization until selinux_complete_init,
1240                    after the initial policy is loaded and the security
1241                    server is ready to handle calls. */
1242                 spin_lock(&sbsec->isec_lock);
1243                 if (list_empty(&isec->list))
1244                         list_add(&isec->list, &sbsec->isec_head);
1245                 spin_unlock(&sbsec->isec_lock);
1246                 goto out_unlock;
1247         }
1248
1249         switch (sbsec->behavior) {
1250         case SECURITY_FS_USE_XATTR:
1251                 if (!inode->i_op->getxattr) {
1252                         isec->sid = sbsec->def_sid;
1253                         break;
1254                 }
1255
1256                 /* Need a dentry, since the xattr API requires one.
1257                    Life would be simpler if we could just pass the inode. */
1258                 if (opt_dentry) {
1259                         /* Called from d_instantiate or d_splice_alias. */
1260                         dentry = dget(opt_dentry);
1261                 } else {
1262                         /* Called from selinux_complete_init, try to find a dentry. */
1263                         dentry = d_find_alias(inode);
1264                 }
1265                 if (!dentry) {
1266                         printk(KERN_WARNING "SELinux: %s:  no dentry for dev=%s "
1267                                "ino=%ld\n", __func__, inode->i_sb->s_id,
1268                                inode->i_ino);
1269                         goto out_unlock;
1270                 }
1271
1272                 len = INITCONTEXTLEN;
1273                 context = kmalloc(len, GFP_NOFS);
1274                 if (!context) {
1275                         rc = -ENOMEM;
1276                         dput(dentry);
1277                         goto out_unlock;
1278                 }
1279                 rc = inode->i_op->getxattr(dentry, XATTR_NAME_SELINUX,
1280                                            context, len);
1281                 if (rc == -ERANGE) {
1282                         /* Need a larger buffer.  Query for the right size. */
1283                         rc = inode->i_op->getxattr(dentry, XATTR_NAME_SELINUX,
1284                                                    NULL, 0);
1285                         if (rc < 0) {
1286                                 dput(dentry);
1287                                 goto out_unlock;
1288                         }
1289                         kfree(context);
1290                         len = rc;
1291                         context = kmalloc(len, GFP_NOFS);
1292                         if (!context) {
1293                                 rc = -ENOMEM;
1294                                 dput(dentry);
1295                                 goto out_unlock;
1296                         }
1297                         rc = inode->i_op->getxattr(dentry,
1298                                                    XATTR_NAME_SELINUX,
1299                                                    context, len);
1300                 }
1301                 dput(dentry);
1302                 if (rc < 0) {
1303                         if (rc != -ENODATA) {
1304                                 printk(KERN_WARNING "SELinux: %s:  getxattr returned "
1305                                        "%d for dev=%s ino=%ld\n", __func__,
1306                                        -rc, inode->i_sb->s_id, inode->i_ino);
1307                                 kfree(context);
1308                                 goto out_unlock;
1309                         }
1310                         /* Map ENODATA to the default file SID */
1311                         sid = sbsec->def_sid;
1312                         rc = 0;
1313                 } else {
1314                         rc = security_context_to_sid_default(context, rc, &sid,
1315                                                              sbsec->def_sid,
1316                                                              GFP_NOFS);
1317                         if (rc) {
1318                                 printk(KERN_WARNING "SELinux: %s:  context_to_sid(%s) "
1319                                        "returned %d for dev=%s ino=%ld\n",
1320                                        __func__, context, -rc,
1321                                        inode->i_sb->s_id, inode->i_ino);
1322                                 kfree(context);
1323                                 /* Leave with the unlabeled SID */
1324                                 rc = 0;
1325                                 break;
1326                         }
1327                 }
1328                 kfree(context);
1329                 isec->sid = sid;
1330                 break;
1331         case SECURITY_FS_USE_TASK:
1332                 isec->sid = isec->task_sid;
1333                 break;
1334         case SECURITY_FS_USE_TRANS:
1335                 /* Default to the fs SID. */
1336                 isec->sid = sbsec->sid;
1337
1338                 /* Try to obtain a transition SID. */
1339                 isec->sclass = inode_mode_to_security_class(inode->i_mode);
1340                 rc = security_transition_sid(isec->task_sid,
1341                                              sbsec->sid,
1342                                              isec->sclass,
1343                                              &sid);
1344                 if (rc)
1345                         goto out_unlock;
1346                 isec->sid = sid;
1347                 break;
1348         case SECURITY_FS_USE_MNTPOINT:
1349                 isec->sid = sbsec->mntpoint_sid;
1350                 break;
1351         default:
1352                 /* Default to the fs superblock SID. */
1353                 isec->sid = sbsec->sid;
1354
1355                 if ((sbsec->flags & SE_SBPROC) && !S_ISLNK(inode->i_mode)) {
1356                         struct proc_inode *proci = PROC_I(inode);
1357                         if (proci->pde) {
1358                                 isec->sclass = inode_mode_to_security_class(inode->i_mode);
1359                                 rc = selinux_proc_get_sid(proci->pde,
1360                                                           isec->sclass,
1361                                                           &sid);
1362                                 if (rc)
1363                                         goto out_unlock;
1364                                 isec->sid = sid;
1365                         }
1366                 }
1367                 break;
1368         }
1369
1370         isec->initialized = 1;
1371
1372 out_unlock:
1373         mutex_unlock(&isec->lock);
1374 out:
1375         if (isec->sclass == SECCLASS_FILE)
1376                 isec->sclass = inode_mode_to_security_class(inode->i_mode);
1377         return rc;
1378 }
1379
1380 /* Convert a Linux signal to an access vector. */
1381 static inline u32 signal_to_av(int sig)
1382 {
1383         u32 perm = 0;
1384
1385         switch (sig) {
1386         case SIGCHLD:
1387                 /* Commonly granted from child to parent. */
1388                 perm = PROCESS__SIGCHLD;
1389                 break;
1390         case SIGKILL:
1391                 /* Cannot be caught or ignored */
1392                 perm = PROCESS__SIGKILL;
1393                 break;
1394         case SIGSTOP:
1395                 /* Cannot be caught or ignored */
1396                 perm = PROCESS__SIGSTOP;
1397                 break;
1398         default:
1399                 /* All other signals. */
1400                 perm = PROCESS__SIGNAL;
1401                 break;
1402         }
1403
1404         return perm;
1405 }
1406
1407 /*
1408  * Check permission between a pair of credentials
1409  * fork check, ptrace check, etc.
1410  */
1411 static int cred_has_perm(const struct cred *actor,
1412                          const struct cred *target,
1413                          u32 perms)
1414 {
1415         u32 asid = cred_sid(actor), tsid = cred_sid(target);
1416
1417         return avc_has_perm(asid, tsid, SECCLASS_PROCESS, perms, NULL);
1418 }
1419
1420 /*
1421  * Check permission between a pair of tasks, e.g. signal checks,
1422  * fork check, ptrace check, etc.
1423  * tsk1 is the actor and tsk2 is the target
1424  * - this uses the default subjective creds of tsk1
1425  */
1426 static int task_has_perm(const struct task_struct *tsk1,
1427                          const struct task_struct *tsk2,
1428                          u32 perms)
1429 {
1430         const struct task_security_struct *__tsec1, *__tsec2;
1431         u32 sid1, sid2;
1432
1433         rcu_read_lock();
1434         __tsec1 = __task_cred(tsk1)->security;  sid1 = __tsec1->sid;
1435         __tsec2 = __task_cred(tsk2)->security;  sid2 = __tsec2->sid;
1436         rcu_read_unlock();
1437         return avc_has_perm(sid1, sid2, SECCLASS_PROCESS, perms, NULL);
1438 }
1439
1440 /*
1441  * Check permission between current and another task, e.g. signal checks,
1442  * fork check, ptrace check, etc.
1443  * current is the actor and tsk2 is the target
1444  * - this uses current's subjective creds
1445  */
1446 static int current_has_perm(const struct task_struct *tsk,
1447                             u32 perms)
1448 {
1449         u32 sid, tsid;
1450
1451         sid = current_sid();
1452         tsid = task_sid(tsk);
1453         return avc_has_perm(sid, tsid, SECCLASS_PROCESS, perms, NULL);
1454 }
1455
1456 #if CAP_LAST_CAP > 63
1457 #error Fix SELinux to handle capabilities > 63.
1458 #endif
1459
1460 /* Check whether a task is allowed to use a capability. */
1461 static int task_has_capability(struct task_struct *tsk,
1462                                const struct cred *cred,
1463                                int cap, int audit)
1464 {
1465         struct avc_audit_data ad;
1466         struct av_decision avd;
1467         u16 sclass;
1468         u32 sid = cred_sid(cred);
1469         u32 av = CAP_TO_MASK(cap);
1470         int rc;
1471
1472         AVC_AUDIT_DATA_INIT(&ad, CAP);
1473         ad.tsk = tsk;
1474         ad.u.cap = cap;
1475
1476         switch (CAP_TO_INDEX(cap)) {
1477         case 0:
1478                 sclass = SECCLASS_CAPABILITY;
1479                 break;
1480         case 1:
1481                 sclass = SECCLASS_CAPABILITY2;
1482                 break;
1483         default:
1484                 printk(KERN_ERR
1485                        "SELinux:  out of range capability %d\n", cap);
1486                 BUG();
1487         }
1488
1489         rc = avc_has_perm_noaudit(sid, sid, sclass, av, 0, &avd);
1490         if (audit == SECURITY_CAP_AUDIT)
1491                 avc_audit(sid, sid, sclass, av, &avd, rc, &ad);
1492         return rc;
1493 }
1494
1495 /* Check whether a task is allowed to use a system operation. */
1496 static int task_has_system(struct task_struct *tsk,
1497                            u32 perms)
1498 {
1499         u32 sid = task_sid(tsk);
1500
1501         return avc_has_perm(sid, SECINITSID_KERNEL,
1502                             SECCLASS_SYSTEM, perms, NULL);
1503 }
1504
1505 /* Check whether a task has a particular permission to an inode.
1506    The 'adp' parameter is optional and allows other audit
1507    data to be passed (e.g. the dentry). */
1508 static int inode_has_perm(const struct cred *cred,
1509                           struct inode *inode,
1510                           u32 perms,
1511                           struct avc_audit_data *adp)
1512 {
1513         struct inode_security_struct *isec;
1514         struct avc_audit_data ad;
1515         u32 sid;
1516
1517         if (unlikely(IS_PRIVATE(inode)))
1518                 return 0;
1519
1520         sid = cred_sid(cred);
1521         isec = inode->i_security;
1522
1523         if (!adp) {
1524                 adp = &ad;
1525                 AVC_AUDIT_DATA_INIT(&ad, FS);
1526                 ad.u.fs.inode = inode;
1527         }
1528
1529         return avc_has_perm(sid, isec->sid, isec->sclass, perms, adp);
1530 }
1531
1532 /* Same as inode_has_perm, but pass explicit audit data containing
1533    the dentry to help the auditing code to more easily generate the
1534    pathname if needed. */
1535 static inline int dentry_has_perm(const struct cred *cred,
1536                                   struct vfsmount *mnt,
1537                                   struct dentry *dentry,
1538                                   u32 av)
1539 {
1540         struct inode *inode = dentry->d_inode;
1541         struct avc_audit_data ad;
1542
1543         AVC_AUDIT_DATA_INIT(&ad, FS);
1544         ad.u.fs.path.mnt = mnt;
1545         ad.u.fs.path.dentry = dentry;
1546         return inode_has_perm(cred, inode, av, &ad);
1547 }
1548
1549 /* Check whether a task can use an open file descriptor to
1550    access an inode in a given way.  Check access to the
1551    descriptor itself, and then use dentry_has_perm to
1552    check a particular permission to the file.
1553    Access to the descriptor is implicitly granted if it
1554    has the same SID as the process.  If av is zero, then
1555    access to the file is not checked, e.g. for cases
1556    where only the descriptor is affected like seek. */
1557 static int file_has_perm(const struct cred *cred,
1558                          struct file *file,
1559                          u32 av)
1560 {
1561         struct file_security_struct *fsec = file->f_security;
1562         struct inode *inode = file->f_path.dentry->d_inode;
1563         struct avc_audit_data ad;
1564         u32 sid = cred_sid(cred);
1565         int rc;
1566
1567         AVC_AUDIT_DATA_INIT(&ad, FS);
1568         ad.u.fs.path = file->f_path;
1569
1570         if (sid != fsec->sid) {
1571                 rc = avc_has_perm(sid, fsec->sid,
1572                                   SECCLASS_FD,
1573                                   FD__USE,
1574                                   &ad);
1575                 if (rc)
1576                         goto out;
1577         }
1578
1579         /* av is zero if only checking access to the descriptor. */
1580         rc = 0;
1581         if (av)
1582                 rc = inode_has_perm(cred, inode, av, &ad);
1583
1584 out:
1585         return rc;
1586 }
1587
1588 /* Check whether a task can create a file. */
1589 static int may_create(struct inode *dir,
1590                       struct dentry *dentry,
1591                       u16 tclass)
1592 {
1593         const struct cred *cred = current_cred();
1594         const struct task_security_struct *tsec = cred->security;
1595         struct inode_security_struct *dsec;
1596         struct superblock_security_struct *sbsec;
1597         u32 sid, newsid;
1598         struct avc_audit_data ad;
1599         int rc;
1600
1601         dsec = dir->i_security;
1602         sbsec = dir->i_sb->s_security;
1603
1604         sid = tsec->sid;
1605         newsid = tsec->create_sid;
1606
1607         AVC_AUDIT_DATA_INIT(&ad, FS);
1608         ad.u.fs.path.dentry = dentry;
1609
1610         rc = avc_has_perm(sid, dsec->sid, SECCLASS_DIR,
1611                           DIR__ADD_NAME | DIR__SEARCH,
1612                           &ad);
1613         if (rc)
1614                 return rc;
1615
1616         if (!newsid || !(sbsec->flags & SE_SBLABELSUPP)) {
1617                 rc = security_transition_sid(sid, dsec->sid, tclass, &newsid);
1618                 if (rc)
1619                         return rc;
1620         }
1621
1622         rc = avc_has_perm(sid, newsid, tclass, FILE__CREATE, &ad);
1623         if (rc)
1624                 return rc;
1625
1626         return avc_has_perm(newsid, sbsec->sid,
1627                             SECCLASS_FILESYSTEM,
1628                             FILESYSTEM__ASSOCIATE, &ad);
1629 }
1630
1631 /* Check whether a task can create a key. */
1632 static int may_create_key(u32 ksid,
1633                           struct task_struct *ctx)
1634 {
1635         u32 sid = task_sid(ctx);
1636
1637         return avc_has_perm(sid, ksid, SECCLASS_KEY, KEY__CREATE, NULL);
1638 }
1639
1640 #define MAY_LINK        0
1641 #define MAY_UNLINK      1
1642 #define MAY_RMDIR       2
1643
1644 /* Check whether a task can link, unlink, or rmdir a file/directory. */
1645 static int may_link(struct inode *dir,
1646                     struct dentry *dentry,
1647                     int kind)
1648
1649 {
1650         struct inode_security_struct *dsec, *isec;
1651         struct avc_audit_data ad;
1652         u32 sid = current_sid();
1653         u32 av;
1654         int rc;
1655
1656         dsec = dir->i_security;
1657         isec = dentry->d_inode->i_security;
1658
1659         AVC_AUDIT_DATA_INIT(&ad, FS);
1660         ad.u.fs.path.dentry = dentry;
1661
1662         av = DIR__SEARCH;
1663         av |= (kind ? DIR__REMOVE_NAME : DIR__ADD_NAME);
1664         rc = avc_has_perm(sid, dsec->sid, SECCLASS_DIR, av, &ad);
1665         if (rc)
1666                 return rc;
1667
1668         switch (kind) {
1669         case MAY_LINK:
1670                 av = FILE__LINK;
1671                 break;
1672         case MAY_UNLINK:
1673                 av = FILE__UNLINK;
1674                 break;
1675         case MAY_RMDIR:
1676                 av = DIR__RMDIR;
1677                 break;
1678         default:
1679                 printk(KERN_WARNING "SELinux: %s:  unrecognized kind %d\n",
1680                         __func__, kind);
1681                 return 0;
1682         }
1683
1684         rc = avc_has_perm(sid, isec->sid, isec->sclass, av, &ad);
1685         return rc;
1686 }
1687
1688 static inline int may_rename(struct inode *old_dir,
1689                              struct dentry *old_dentry,
1690                              struct inode *new_dir,
1691                              struct dentry *new_dentry)
1692 {
1693         struct inode_security_struct *old_dsec, *new_dsec, *old_isec, *new_isec;
1694         struct avc_audit_data ad;
1695         u32 sid = current_sid();
1696         u32 av;
1697         int old_is_dir, new_is_dir;
1698         int rc;
1699
1700         old_dsec = old_dir->i_security;
1701         old_isec = old_dentry->d_inode->i_security;
1702         old_is_dir = S_ISDIR(old_dentry->d_inode->i_mode);
1703         new_dsec = new_dir->i_security;
1704
1705         AVC_AUDIT_DATA_INIT(&ad, FS);
1706
1707         ad.u.fs.path.dentry = old_dentry;
1708         rc = avc_has_perm(sid, old_dsec->sid, SECCLASS_DIR,
1709                           DIR__REMOVE_NAME | DIR__SEARCH, &ad);
1710         if (rc)
1711                 return rc;
1712         rc = avc_has_perm(sid, old_isec->sid,
1713                           old_isec->sclass, FILE__RENAME, &ad);
1714         if (rc)
1715                 return rc;
1716         if (old_is_dir && new_dir != old_dir) {
1717                 rc = avc_has_perm(sid, old_isec->sid,
1718                                   old_isec->sclass, DIR__REPARENT, &ad);
1719                 if (rc)
1720                         return rc;
1721         }
1722
1723         ad.u.fs.path.dentry = new_dentry;
1724         av = DIR__ADD_NAME | DIR__SEARCH;
1725         if (new_dentry->d_inode)
1726                 av |= DIR__REMOVE_NAME;
1727         rc = avc_has_perm(sid, new_dsec->sid, SECCLASS_DIR, av, &ad);
1728         if (rc)
1729                 return rc;
1730         if (new_dentry->d_inode) {
1731                 new_isec = new_dentry->d_inode->i_security;
1732                 new_is_dir = S_ISDIR(new_dentry->d_inode->i_mode);
1733                 rc = avc_has_perm(sid, new_isec->sid,
1734                                   new_isec->sclass,
1735                                   (new_is_dir ? DIR__RMDIR : FILE__UNLINK), &ad);
1736                 if (rc)
1737                         return rc;
1738         }
1739
1740         return 0;
1741 }
1742
1743 /* Check whether a task can perform a filesystem operation. */
1744 static int superblock_has_perm(const struct cred *cred,
1745                                struct super_block *sb,
1746                                u32 perms,
1747                                struct avc_audit_data *ad)
1748 {
1749         struct superblock_security_struct *sbsec;
1750         u32 sid = cred_sid(cred);
1751
1752         sbsec = sb->s_security;
1753         return avc_has_perm(sid, sbsec->sid, SECCLASS_FILESYSTEM, perms, ad);
1754 }
1755
1756 /* Convert a Linux mode and permission mask to an access vector. */
1757 static inline u32 file_mask_to_av(int mode, int mask)
1758 {
1759         u32 av = 0;
1760
1761         if ((mode & S_IFMT) != S_IFDIR) {
1762                 if (mask & MAY_EXEC)
1763                         av |= FILE__EXECUTE;
1764                 if (mask & MAY_READ)
1765                         av |= FILE__READ;
1766
1767                 if (mask & MAY_APPEND)
1768                         av |= FILE__APPEND;
1769                 else if (mask & MAY_WRITE)
1770                         av |= FILE__WRITE;
1771
1772         } else {
1773                 if (mask & MAY_EXEC)
1774                         av |= DIR__SEARCH;
1775                 if (mask & MAY_WRITE)
1776                         av |= DIR__WRITE;
1777                 if (mask & MAY_READ)
1778                         av |= DIR__READ;
1779         }
1780
1781         return av;
1782 }
1783
1784 /* Convert a Linux file to an access vector. */
1785 static inline u32 file_to_av(struct file *file)
1786 {
1787         u32 av = 0;
1788
1789         if (file->f_mode & FMODE_READ)
1790                 av |= FILE__READ;
1791         if (file->f_mode & FMODE_WRITE) {
1792                 if (file->f_flags & O_APPEND)
1793                         av |= FILE__APPEND;
1794                 else
1795                         av |= FILE__WRITE;
1796         }
1797         if (!av) {
1798                 /*
1799                  * Special file opened with flags 3 for ioctl-only use.
1800                  */
1801                 av = FILE__IOCTL;
1802         }
1803
1804         return av;
1805 }
1806
1807 /*
1808  * Convert a file to an access vector and include the correct open
1809  * open permission.
1810  */
1811 static inline u32 open_file_to_av(struct file *file)
1812 {
1813         u32 av = file_to_av(file);
1814
1815         if (selinux_policycap_openperm) {
1816                 mode_t mode = file->f_path.dentry->d_inode->i_mode;
1817                 /*
1818                  * lnk files and socks do not really have an 'open'
1819                  */
1820                 if (S_ISREG(mode))
1821                         av |= FILE__OPEN;
1822                 else if (S_ISCHR(mode))
1823                         av |= CHR_FILE__OPEN;
1824                 else if (S_ISBLK(mode))
1825                         av |= BLK_FILE__OPEN;
1826                 else if (S_ISFIFO(mode))
1827                         av |= FIFO_FILE__OPEN;
1828                 else if (S_ISDIR(mode))
1829                         av |= DIR__OPEN;
1830                 else
1831                         printk(KERN_ERR "SELinux: WARNING: inside %s with "
1832                                 "unknown mode:%o\n", __func__, mode);
1833         }
1834         return av;
1835 }
1836
1837 /* Hook functions begin here. */
1838
1839 static int selinux_ptrace_may_access(struct task_struct *child,
1840                                      unsigned int mode)
1841 {
1842         int rc;
1843
1844         rc = secondary_ops->ptrace_may_access(child, mode);
1845         if (rc)
1846                 return rc;
1847
1848         if (mode == PTRACE_MODE_READ) {
1849                 u32 sid = current_sid();
1850                 u32 csid = task_sid(child);
1851                 return avc_has_perm(sid, csid, SECCLASS_FILE, FILE__READ, NULL);
1852         }
1853
1854         return current_has_perm(child, PROCESS__PTRACE);
1855 }
1856
1857 static int selinux_ptrace_traceme(struct task_struct *parent)
1858 {
1859         int rc;
1860
1861         rc = secondary_ops->ptrace_traceme(parent);
1862         if (rc)
1863                 return rc;
1864
1865         return task_has_perm(parent, current, PROCESS__PTRACE);
1866 }
1867
1868 static int selinux_capget(struct task_struct *target, kernel_cap_t *effective,
1869                           kernel_cap_t *inheritable, kernel_cap_t *permitted)
1870 {
1871         int error;
1872
1873         error = current_has_perm(target, PROCESS__GETCAP);
1874         if (error)
1875                 return error;
1876
1877         return secondary_ops->capget(target, effective, inheritable, permitted);
1878 }
1879
1880 static int selinux_capset(struct cred *new, const struct cred *old,
1881                           const kernel_cap_t *effective,
1882                           const kernel_cap_t *inheritable,
1883                           const kernel_cap_t *permitted)
1884 {
1885         int error;
1886
1887         error = secondary_ops->capset(new, old,
1888                                       effective, inheritable, permitted);
1889         if (error)
1890                 return error;
1891
1892         return cred_has_perm(old, new, PROCESS__SETCAP);
1893 }
1894
1895 static int selinux_capable(struct task_struct *tsk, const struct cred *cred,
1896                            int cap, int audit)
1897 {
1898         int rc;
1899
1900         rc = secondary_ops->capable(tsk, cred, cap, audit);
1901         if (rc)
1902                 return rc;
1903
1904         return task_has_capability(tsk, cred, cap, audit);
1905 }
1906
1907 static int selinux_sysctl_get_sid(ctl_table *table, u16 tclass, u32 *sid)
1908 {
1909         int buflen, rc;
1910         char *buffer, *path, *end;
1911
1912         rc = -ENOMEM;
1913         buffer = (char *)__get_free_page(GFP_KERNEL);
1914         if (!buffer)
1915                 goto out;
1916
1917         buflen = PAGE_SIZE;
1918         end = buffer+buflen;
1919         *--end = '\0';
1920         buflen--;
1921         path = end-1;
1922         *path = '/';
1923         while (table) {
1924                 const char *name = table->procname;
1925                 size_t namelen = strlen(name);
1926                 buflen -= namelen + 1;
1927                 if (buflen < 0)
1928                         goto out_free;
1929                 end -= namelen;
1930                 memcpy(end, name, namelen);
1931                 *--end = '/';
1932                 path = end;
1933                 table = table->parent;
1934         }
1935         buflen -= 4;
1936         if (buflen < 0)
1937                 goto out_free;
1938         end -= 4;
1939         memcpy(end, "/sys", 4);
1940         path = end;
1941         rc = security_genfs_sid("proc", path, tclass, sid);
1942 out_free:
1943         free_page((unsigned long)buffer);
1944 out:
1945         return rc;
1946 }
1947
1948 static int selinux_sysctl(ctl_table *table, int op)
1949 {
1950         int error = 0;
1951         u32 av;
1952         u32 tsid, sid;
1953         int rc;
1954
1955         rc = secondary_ops->sysctl(table, op);
1956         if (rc)
1957                 return rc;
1958
1959         sid = current_sid();
1960
1961         rc = selinux_sysctl_get_sid(table, (op == 0001) ?
1962                                     SECCLASS_DIR : SECCLASS_FILE, &tsid);
1963         if (rc) {
1964                 /* Default to the well-defined sysctl SID. */
1965                 tsid = SECINITSID_SYSCTL;
1966         }
1967
1968         /* The op values are "defined" in sysctl.c, thereby creating
1969          * a bad coupling between this module and sysctl.c */
1970         if (op == 001) {
1971                 error = avc_has_perm(sid, tsid,
1972                                      SECCLASS_DIR, DIR__SEARCH, NULL);
1973         } else {
1974                 av = 0;
1975                 if (op & 004)
1976                         av |= FILE__READ;
1977                 if (op & 002)
1978                         av |= FILE__WRITE;
1979                 if (av)
1980                         error = avc_has_perm(sid, tsid,
1981                                              SECCLASS_FILE, av, NULL);
1982         }
1983
1984         return error;
1985 }
1986
1987 static int selinux_quotactl(int cmds, int type, int id, struct super_block *sb)
1988 {
1989         const struct cred *cred = current_cred();
1990         int rc = 0;
1991
1992         if (!sb)
1993                 return 0;
1994
1995         switch (cmds) {
1996         case Q_SYNC:
1997         case Q_QUOTAON:
1998         case Q_QUOTAOFF:
1999         case Q_SETINFO:
2000         case Q_SETQUOTA:
2001                 rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAMOD, NULL);
2002                 break;
2003         case Q_GETFMT:
2004         case Q_GETINFO:
2005         case Q_GETQUOTA:
2006                 rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAGET, NULL);
2007                 break;
2008         default:
2009                 rc = 0;  /* let the kernel handle invalid cmds */
2010                 break;
2011         }
2012         return rc;
2013 }
2014
2015 static int selinux_quota_on(struct dentry *dentry)
2016 {
2017         const struct cred *cred = current_cred();
2018
2019         return dentry_has_perm(cred, NULL, dentry, FILE__QUOTAON);
2020 }
2021
2022 static int selinux_syslog(int type)
2023 {
2024         int rc;
2025
2026         rc = secondary_ops->syslog(type);
2027         if (rc)
2028                 return rc;
2029
2030         switch (type) {
2031         case 3:         /* Read last kernel messages */
2032         case 10:        /* Return size of the log buffer */
2033                 rc = task_has_system(current, SYSTEM__SYSLOG_READ);
2034                 break;
2035         case 6:         /* Disable logging to console */
2036         case 7:         /* Enable logging to console */
2037         case 8:         /* Set level of messages printed to console */
2038                 rc = task_has_system(current, SYSTEM__SYSLOG_CONSOLE);
2039                 break;
2040         case 0:         /* Close log */
2041         case 1:         /* Open log */
2042         case 2:         /* Read from log */
2043         case 4:         /* Read/clear last kernel messages */
2044         case 5:         /* Clear ring buffer */
2045         default:
2046                 rc = task_has_system(current, SYSTEM__SYSLOG_MOD);
2047                 break;
2048         }
2049         return rc;
2050 }
2051
2052 /*
2053  * Check that a process has enough memory to allocate a new virtual
2054  * mapping. 0 means there is enough memory for the allocation to
2055  * succeed and -ENOMEM implies there is not.
2056  *
2057  * Note that secondary_ops->capable and task_has_perm_noaudit return 0
2058  * if the capability is granted, but __vm_enough_memory requires 1 if
2059  * the capability is granted.
2060  *
2061  * Do not audit the selinux permission check, as this is applied to all
2062  * processes that allocate mappings.
2063  */
2064 static int selinux_vm_enough_memory(struct mm_struct *mm, long pages)
2065 {
2066         int rc, cap_sys_admin = 0;
2067
2068         rc = selinux_capable(current, current_cred(), CAP_SYS_ADMIN,
2069                              SECURITY_CAP_NOAUDIT);
2070         if (rc == 0)
2071                 cap_sys_admin = 1;
2072
2073         return __vm_enough_memory(mm, pages, cap_sys_admin);
2074 }
2075
2076 /* binprm security operations */
2077
2078 static int selinux_bprm_set_creds(struct linux_binprm *bprm)
2079 {
2080         const struct task_security_struct *old_tsec;
2081         struct task_security_struct *new_tsec;
2082         struct inode_security_struct *isec;
2083         struct avc_audit_data ad;
2084         struct inode *inode = bprm->file->f_path.dentry->d_inode;
2085         int rc;
2086
2087         rc = secondary_ops->bprm_set_creds(bprm);
2088         if (rc)
2089                 return rc;
2090
2091         /* SELinux context only depends on initial program or script and not
2092          * the script interpreter */
2093         if (bprm->cred_prepared)
2094                 return 0;
2095
2096         old_tsec = current_security();
2097         new_tsec = bprm->cred->security;
2098         isec = inode->i_security;
2099
2100         /* Default to the current task SID. */
2101         new_tsec->sid = old_tsec->sid;
2102         new_tsec->osid = old_tsec->sid;
2103
2104         /* Reset fs, key, and sock SIDs on execve. */
2105         new_tsec->create_sid = 0;
2106         new_tsec->keycreate_sid = 0;
2107         new_tsec->sockcreate_sid = 0;
2108
2109         if (old_tsec->exec_sid) {
2110                 new_tsec->sid = old_tsec->exec_sid;
2111                 /* Reset exec SID on execve. */
2112                 new_tsec->exec_sid = 0;
2113         } else {
2114                 /* Check for a default transition on this program. */
2115                 rc = security_transition_sid(old_tsec->sid, isec->sid,
2116                                              SECCLASS_PROCESS, &new_tsec->sid);
2117                 if (rc)
2118                         return rc;
2119         }
2120
2121         AVC_AUDIT_DATA_INIT(&ad, FS);
2122         ad.u.fs.path = bprm->file->f_path;
2123
2124         if (bprm->file->f_path.mnt->mnt_flags & MNT_NOSUID)
2125                 new_tsec->sid = old_tsec->sid;
2126
2127         if (new_tsec->sid == old_tsec->sid) {
2128                 rc = avc_has_perm(old_tsec->sid, isec->sid,
2129                                   SECCLASS_FILE, FILE__EXECUTE_NO_TRANS, &ad);
2130                 if (rc)
2131                         return rc;
2132         } else {
2133                 /* Check permissions for the transition. */
2134                 rc = avc_has_perm(old_tsec->sid, new_tsec->sid,
2135                                   SECCLASS_PROCESS, PROCESS__TRANSITION, &ad);
2136                 if (rc)
2137                         return rc;
2138
2139                 rc = avc_has_perm(new_tsec->sid, isec->sid,
2140                                   SECCLASS_FILE, FILE__ENTRYPOINT, &ad);
2141                 if (rc)
2142                         return rc;
2143
2144                 /* Check for shared state */
2145                 if (bprm->unsafe & LSM_UNSAFE_SHARE) {
2146                         rc = avc_has_perm(old_tsec->sid, new_tsec->sid,
2147                                           SECCLASS_PROCESS, PROCESS__SHARE,
2148                                           NULL);
2149                         if (rc)
2150                                 return -EPERM;
2151                 }
2152
2153                 /* Make sure that anyone attempting to ptrace over a task that
2154                  * changes its SID has the appropriate permit */
2155                 if (bprm->unsafe &
2156                     (LSM_UNSAFE_PTRACE | LSM_UNSAFE_PTRACE_CAP)) {
2157                         struct task_struct *tracer;
2158                         struct task_security_struct *sec;
2159                         u32 ptsid = 0;
2160
2161                         rcu_read_lock();
2162                         tracer = tracehook_tracer_task(current);
2163                         if (likely(tracer != NULL)) {
2164                                 sec = __task_cred(tracer)->security;
2165                                 ptsid = sec->sid;
2166                         }
2167                         rcu_read_unlock();
2168
2169                         if (ptsid != 0) {
2170                                 rc = avc_has_perm(ptsid, new_tsec->sid,
2171                                                   SECCLASS_PROCESS,
2172                                                   PROCESS__PTRACE, NULL);
2173                                 if (rc)
2174                                         return -EPERM;
2175                         }
2176                 }
2177
2178                 /* Clear any possibly unsafe personality bits on exec: */
2179                 bprm->per_clear |= PER_CLEAR_ON_SETID;
2180         }
2181
2182         return 0;
2183 }
2184
2185 static int selinux_bprm_secureexec(struct linux_binprm *bprm)
2186 {
2187         const struct cred *cred = current_cred();
2188         const struct task_security_struct *tsec = cred->security;
2189         u32 sid, osid;
2190         int atsecure = 0;
2191
2192         sid = tsec->sid;
2193         osid = tsec->osid;
2194
2195         if (osid != sid) {
2196                 /* Enable secure mode for SIDs transitions unless
2197                    the noatsecure permission is granted between
2198                    the two SIDs, i.e. ahp returns 0. */
2199                 atsecure = avc_has_perm(osid, sid,
2200                                         SECCLASS_PROCESS,
2201                                         PROCESS__NOATSECURE, NULL);
2202         }
2203
2204         return (atsecure || secondary_ops->bprm_secureexec(bprm));
2205 }
2206
2207 extern struct vfsmount *selinuxfs_mount;
2208 extern struct dentry *selinux_null;
2209
2210 /* Derived from fs/exec.c:flush_old_files. */
2211 static inline void flush_unauthorized_files(const struct cred *cred,
2212                                             struct files_struct *files)
2213 {
2214         struct avc_audit_data ad;
2215         struct file *file, *devnull = NULL;
2216         struct tty_struct *tty;
2217         struct fdtable *fdt;
2218         long j = -1;
2219         int drop_tty = 0;
2220
2221         tty = get_current_tty();
2222         if (tty) {
2223                 file_list_lock();
2224                 if (!list_empty(&tty->tty_files)) {
2225                         struct inode *inode;
2226
2227                         /* Revalidate access to controlling tty.
2228                            Use inode_has_perm on the tty inode directly rather
2229                            than using file_has_perm, as this particular open
2230                            file may belong to another process and we are only
2231                            interested in the inode-based check here. */
2232                         file = list_first_entry(&tty->tty_files, struct file, f_u.fu_list);
2233                         inode = file->f_path.dentry->d_inode;
2234                         if (inode_has_perm(cred, inode,
2235                                            FILE__READ | FILE__WRITE, NULL)) {
2236                                 drop_tty = 1;
2237                         }
2238                 }
2239                 file_list_unlock();
2240                 tty_kref_put(tty);
2241         }
2242         /* Reset controlling tty. */
2243         if (drop_tty)
2244                 no_tty();
2245
2246         /* Revalidate access to inherited open files. */
2247
2248         AVC_AUDIT_DATA_INIT(&ad, FS);
2249
2250         spin_lock(&files->file_lock);
2251         for (;;) {
2252                 unsigned long set, i;
2253                 int fd;
2254
2255                 j++;
2256                 i = j * __NFDBITS;
2257                 fdt = files_fdtable(files);
2258                 if (i >= fdt->max_fds)
2259                         break;
2260                 set = fdt->open_fds->fds_bits[j];
2261                 if (!set)
2262                         continue;
2263                 spin_unlock(&files->file_lock);
2264                 for ( ; set ; i++, set >>= 1) {
2265                         if (set & 1) {
2266                                 file = fget(i);
2267                                 if (!file)
2268                                         continue;
2269                                 if (file_has_perm(cred,
2270                                                   file,
2271                                                   file_to_av(file))) {
2272                                         sys_close(i);
2273                                         fd = get_unused_fd();
2274                                         if (fd != i) {
2275                                                 if (fd >= 0)
2276                                                         put_unused_fd(fd);
2277                                                 fput(file);
2278                                                 continue;
2279                                         }
2280                                         if (devnull) {
2281                                                 get_file(devnull);
2282                                         } else {
2283                                                 devnull = dentry_open(
2284                                                         dget(selinux_null),
2285                                                         mntget(selinuxfs_mount),
2286                                                         O_RDWR, cred);
2287                                                 if (IS_ERR(devnull)) {
2288                                                         devnull = NULL;
2289                                                         put_unused_fd(fd);
2290                                                         fput(file);
2291                                                         continue;
2292                                                 }
2293                                         }
2294                                         fd_install(fd, devnull);
2295                                 }
2296                                 fput(file);
2297                         }
2298                 }
2299                 spin_lock(&files->file_lock);
2300
2301         }
2302         spin_unlock(&files->file_lock);
2303 }
2304
2305 /*
2306  * Prepare a process for imminent new credential changes due to exec
2307  */
2308 static void selinux_bprm_committing_creds(struct linux_binprm *bprm)
2309 {
2310         struct task_security_struct *new_tsec;
2311         struct rlimit *rlim, *initrlim;
2312         int rc, i;
2313
2314         new_tsec = bprm->cred->security;
2315         if (new_tsec->sid == new_tsec->osid)
2316                 return;
2317
2318         /* Close files for which the new task SID is not authorized. */
2319         flush_unauthorized_files(bprm->cred, current->files);
2320
2321         /* Always clear parent death signal on SID transitions. */
2322         current->pdeath_signal = 0;
2323
2324         /* Check whether the new SID can inherit resource limits from the old
2325          * SID.  If not, reset all soft limits to the lower of the current
2326          * task's hard limit and the init task's soft limit.
2327          *
2328          * Note that the setting of hard limits (even to lower them) can be
2329          * controlled by the setrlimit check.  The inclusion of the init task's
2330          * soft limit into the computation is to avoid resetting soft limits
2331          * higher than the default soft limit for cases where the default is
2332          * lower than the hard limit, e.g. RLIMIT_CORE or RLIMIT_STACK.
2333          */
2334         rc = avc_has_perm(new_tsec->osid, new_tsec->sid, SECCLASS_PROCESS,
2335                           PROCESS__RLIMITINH, NULL);
2336         if (rc) {
2337                 for (i = 0; i < RLIM_NLIMITS; i++) {
2338                         rlim = current->signal->rlim + i;
2339                         initrlim = init_task.signal->rlim + i;
2340                         rlim->rlim_cur = min(rlim->rlim_max, initrlim->rlim_cur);
2341                 }
2342                 update_rlimit_cpu(rlim->rlim_cur);
2343         }
2344 }
2345
2346 /*
2347  * Clean up the process immediately after the installation of new credentials
2348  * due to exec
2349  */
2350 static void selinux_bprm_committed_creds(struct linux_binprm *bprm)
2351 {
2352         const struct task_security_struct *tsec = current_security();
2353         struct itimerval itimer;
2354         struct sighand_struct *psig;
2355         u32 osid, sid;
2356         int rc, i;
2357         unsigned long flags;
2358
2359         osid = tsec->osid;
2360         sid = tsec->sid;
2361
2362         if (sid == osid)
2363                 return;
2364
2365         /* Check whether the new SID can inherit signal state from the old SID.
2366          * If not, clear itimers to avoid subsequent signal generation and
2367          * flush and unblock signals.
2368          *
2369          * This must occur _after_ the task SID has been updated so that any
2370          * kill done after the flush will be checked against the new SID.
2371          */
2372         rc = avc_has_perm(osid, sid, SECCLASS_PROCESS, PROCESS__SIGINH, NULL);
2373         if (rc) {
2374                 memset(&itimer, 0, sizeof itimer);
2375                 for (i = 0; i < 3; i++)
2376                         do_setitimer(i, &itimer, NULL);
2377                 flush_signals(current);
2378                 spin_lock_irq(&current->sighand->siglock);
2379                 flush_signal_handlers(current, 1);
2380                 sigemptyset(&current->blocked);
2381                 recalc_sigpending();
2382                 spin_unlock_irq(&current->sighand->siglock);
2383         }
2384
2385         /* Wake up the parent if it is waiting so that it can recheck
2386          * wait permission to the new task SID. */
2387         read_lock_irq(&tasklist_lock);
2388         psig = current->parent->sighand;
2389         spin_lock_irqsave(&psig->siglock, flags);
2390         wake_up_interruptible(&current->parent->signal->wait_chldexit);
2391         spin_unlock_irqrestore(&psig->siglock, flags);
2392         read_unlock_irq(&tasklist_lock);
2393 }
2394
2395 /* superblock security operations */
2396
2397 static int selinux_sb_alloc_security(struct super_block *sb)
2398 {
2399         return superblock_alloc_security(sb);
2400 }
2401
2402 static void selinux_sb_free_security(struct super_block *sb)
2403 {
2404         superblock_free_security(sb);
2405 }
2406
2407 static inline int match_prefix(char *prefix, int plen, char *option, int olen)
2408 {
2409         if (plen > olen)
2410                 return 0;
2411
2412         return !memcmp(prefix, option, plen);
2413 }
2414
2415 static inline int selinux_option(char *option, int len)
2416 {
2417         return (match_prefix(CONTEXT_STR, sizeof(CONTEXT_STR)-1, option, len) ||
2418                 match_prefix(FSCONTEXT_STR, sizeof(FSCONTEXT_STR)-1, option, len) ||
2419                 match_prefix(DEFCONTEXT_STR, sizeof(DEFCONTEXT_STR)-1, option, len) ||
2420                 match_prefix(ROOTCONTEXT_STR, sizeof(ROOTCONTEXT_STR)-1, option, len) ||
2421                 match_prefix(LABELSUPP_STR, sizeof(LABELSUPP_STR)-1, option, len));
2422 }
2423
2424 static inline void take_option(char **to, char *from, int *first, int len)
2425 {
2426         if (!*first) {
2427                 **to = ',';
2428                 *to += 1;
2429         } else
2430                 *first = 0;
2431         memcpy(*to, from, len);
2432         *to += len;
2433 }
2434
2435 static inline void take_selinux_option(char **to, char *from, int *first,
2436                                        int len)
2437 {
2438         int current_size = 0;
2439
2440         if (!*first) {
2441                 **to = '|';
2442                 *to += 1;
2443         } else
2444                 *first = 0;
2445
2446         while (current_size < len) {
2447                 if (*from != '"') {
2448                         **to = *from;
2449                         *to += 1;
2450                 }
2451                 from += 1;
2452                 current_size += 1;
2453         }
2454 }
2455
2456 static int selinux_sb_copy_data(char *orig, char *copy)
2457 {
2458         int fnosec, fsec, rc = 0;
2459         char *in_save, *in_curr, *in_end;
2460         char *sec_curr, *nosec_save, *nosec;
2461         int open_quote = 0;
2462
2463         in_curr = orig;
2464         sec_curr = copy;
2465
2466         nosec = (char *)get_zeroed_page(GFP_KERNEL);
2467         if (!nosec) {
2468                 rc = -ENOMEM;
2469                 goto out;
2470         }
2471
2472         nosec_save = nosec;
2473         fnosec = fsec = 1;
2474         in_save = in_end = orig;
2475
2476         do {
2477                 if (*in_end == '"')
2478                         open_quote = !open_quote;
2479                 if ((*in_end == ',' && open_quote == 0) ||
2480                                 *in_end == '\0') {
2481                         int len = in_end - in_curr;
2482
2483                         if (selinux_option(in_curr, len))
2484                                 take_selinux_option(&sec_curr, in_curr, &fsec, len);
2485                         else
2486                                 take_option(&nosec, in_curr, &fnosec, len);
2487
2488                         in_curr = in_end + 1;
2489                 }
2490         } while (*in_end++);
2491
2492         strcpy(in_save, nosec_save);
2493         free_page((unsigned long)nosec_save);
2494 out:
2495         return rc;
2496 }
2497
2498 static int selinux_sb_kern_mount(struct super_block *sb, int flags, void *data)
2499 {
2500         const struct cred *cred = current_cred();
2501         struct avc_audit_data ad;
2502         int rc;
2503
2504         rc = superblock_doinit(sb, data);
2505         if (rc)
2506                 return rc;
2507
2508         /* Allow all mounts performed by the kernel */
2509         if (flags & MS_KERNMOUNT)
2510                 return 0;
2511
2512         AVC_AUDIT_DATA_INIT(&ad, FS);
2513         ad.u.fs.path.dentry = sb->s_root;
2514         return superblock_has_perm(cred, sb, FILESYSTEM__MOUNT, &ad);
2515 }
2516
2517 static int selinux_sb_statfs(struct dentry *dentry)
2518 {
2519         const struct cred *cred = current_cred();
2520         struct avc_audit_data ad;
2521
2522         AVC_AUDIT_DATA_INIT(&ad, FS);
2523         ad.u.fs.path.dentry = dentry->d_sb->s_root;
2524         return superblock_has_perm(cred, dentry->d_sb, FILESYSTEM__GETATTR, &ad);
2525 }
2526
2527 static int selinux_mount(char *dev_name,
2528                          struct path *path,
2529                          char *type,
2530                          unsigned long flags,
2531                          void *data)
2532 {
2533         const struct cred *cred = current_cred();
2534
2535         if (flags & MS_REMOUNT)
2536                 return superblock_has_perm(cred, path->mnt->mnt_sb,
2537                                            FILESYSTEM__REMOUNT, NULL);
2538         else
2539                 return dentry_has_perm(cred, path->mnt, path->dentry,
2540                                        FILE__MOUNTON);
2541 }
2542
2543 static int selinux_umount(struct vfsmount *mnt, int flags)
2544 {
2545         const struct cred *cred = current_cred();
2546
2547         return superblock_has_perm(cred, mnt->mnt_sb,
2548                                    FILESYSTEM__UNMOUNT, NULL);
2549 }
2550
2551 /* inode security operations */
2552
2553 static int selinux_inode_alloc_security(struct inode *inode)
2554 {
2555         return inode_alloc_security(inode);
2556 }
2557
2558 static void selinux_inode_free_security(struct inode *inode)
2559 {
2560         inode_free_security(inode);
2561 }
2562
2563 static int selinux_inode_init_security(struct inode *inode, struct inode *dir,
2564                                        char **name, void **value,
2565                                        size_t *len)
2566 {
2567         const struct cred *cred = current_cred();
2568         const struct task_security_struct *tsec = cred->security;
2569         struct inode_security_struct *dsec;
2570         struct superblock_security_struct *sbsec;
2571         u32 sid, newsid, clen;
2572         int rc;
2573         char *namep = NULL, *context;
2574
2575         dsec = dir->i_security;
2576         sbsec = dir->i_sb->s_security;
2577
2578         sid = tsec->sid;
2579         newsid = tsec->create_sid;
2580
2581         if (!newsid || !(sbsec->flags & SE_SBLABELSUPP)) {
2582                 rc = security_transition_sid(sid, dsec->sid,
2583                                              inode_mode_to_security_class(inode->i_mode),
2584                                              &newsid);
2585                 if (rc) {
2586                         printk(KERN_WARNING "%s:  "
2587                                "security_transition_sid failed, rc=%d (dev=%s "
2588                                "ino=%ld)\n",
2589                                __func__,
2590                                -rc, inode->i_sb->s_id, inode->i_ino);
2591                         return rc;
2592                 }
2593         }
2594
2595         /* Possibly defer initialization to selinux_complete_init. */
2596         if (sbsec->flags & SE_SBINITIALIZED) {
2597                 struct inode_security_struct *isec = inode->i_security;
2598                 isec->sclass = inode_mode_to_security_class(inode->i_mode);
2599                 isec->sid = newsid;
2600                 isec->initialized = 1;
2601         }
2602
2603         if (!ss_initialized || !(sbsec->flags & SE_SBLABELSUPP))
2604                 return -EOPNOTSUPP;
2605
2606         if (name) {
2607                 namep = kstrdup(XATTR_SELINUX_SUFFIX, GFP_NOFS);
2608                 if (!namep)
2609                         return -ENOMEM;
2610                 *name = namep;
2611         }
2612
2613         if (value && len) {
2614                 rc = security_sid_to_context_force(newsid, &context, &clen);
2615                 if (rc) {
2616                         kfree(namep);
2617                         return rc;
2618                 }
2619                 *value = context;
2620                 *len = clen;
2621         }
2622
2623         return 0;
2624 }
2625
2626 static int selinux_inode_create(struct inode *dir, struct dentry *dentry, int mask)
2627 {
2628         return may_create(dir, dentry, SECCLASS_FILE);
2629 }
2630
2631 static int selinux_inode_link(struct dentry *old_dentry, struct inode *dir, struct dentry *new_dentry)
2632 {
2633         return may_link(dir, old_dentry, MAY_LINK);
2634 }
2635
2636 static int selinux_inode_unlink(struct inode *dir, struct dentry *dentry)
2637 {
2638         int rc;
2639
2640         rc = secondary_ops->inode_unlink(dir, dentry);
2641         if (rc)
2642                 return rc;
2643         return may_link(dir, dentry, MAY_UNLINK);
2644 }
2645
2646 static int selinux_inode_symlink(struct inode *dir, struct dentry *dentry, const char *name)
2647 {
2648         return may_create(dir, dentry, SECCLASS_LNK_FILE);
2649 }
2650
2651 static int selinux_inode_mkdir(struct inode *dir, struct dentry *dentry, int mask)
2652 {
2653         return may_create(dir, dentry, SECCLASS_DIR);
2654 }
2655
2656 static int selinux_inode_rmdir(struct inode *dir, struct dentry *dentry)
2657 {
2658         return may_link(dir, dentry, MAY_RMDIR);
2659 }
2660
2661 static int selinux_inode_mknod(struct inode *dir, struct dentry *dentry, int mode, dev_t dev)
2662 {
2663         int rc;
2664
2665         rc = secondary_ops->inode_mknod(dir, dentry, mode, dev);
2666         if (rc)
2667                 return rc;
2668
2669         return may_create(dir, dentry, inode_mode_to_security_class(mode));
2670 }
2671
2672 static int selinux_inode_rename(struct inode *old_inode, struct dentry *old_dentry,
2673                                 struct inode *new_inode, struct dentry *new_dentry)
2674 {
2675         return may_rename(old_inode, old_dentry, new_inode, new_dentry);
2676 }
2677
2678 static int selinux_inode_readlink(struct dentry *dentry)
2679 {
2680         const struct cred *cred = current_cred();
2681
2682         return dentry_has_perm(cred, NULL, dentry, FILE__READ);
2683 }
2684
2685 static int selinux_inode_follow_link(struct dentry *dentry, struct nameidata *nameidata)
2686 {
2687         const struct cred *cred = current_cred();
2688         int rc;
2689
2690         rc = secondary_ops->inode_follow_link(dentry, nameidata);
2691         if (rc)
2692                 return rc;
2693         return dentry_has_perm(cred, NULL, dentry, FILE__READ);
2694 }
2695
2696 static int selinux_inode_permission(struct inode *inode, int mask)
2697 {
2698         const struct cred *cred = current_cred();
2699         int rc;
2700
2701         rc = secondary_ops->inode_permission(inode, mask);
2702         if (rc)
2703                 return rc;
2704
2705         if (!mask) {
2706                 /* No permission to check.  Existence test. */
2707                 return 0;
2708         }
2709
2710         return inode_has_perm(cred, inode,
2711                               file_mask_to_av(inode->i_mode, mask), NULL);
2712 }
2713
2714 static int selinux_inode_setattr(struct dentry *dentry, struct iattr *iattr)
2715 {
2716         const struct cred *cred = current_cred();
2717         int rc;
2718
2719         rc = secondary_ops->inode_setattr(dentry, iattr);
2720         if (rc)
2721                 return rc;
2722
2723         if (iattr->ia_valid & ATTR_FORCE)
2724                 return 0;
2725
2726         if (iattr->ia_valid & (ATTR_MODE | ATTR_UID | ATTR_GID |
2727                                ATTR_ATIME_SET | ATTR_MTIME_SET))
2728                 return dentry_has_perm(cred, NULL, dentry, FILE__SETATTR);
2729
2730         return dentry_has_perm(cred, NULL, dentry, FILE__WRITE);
2731 }
2732
2733 static int selinux_inode_getattr(struct vfsmount *mnt, struct dentry *dentry)
2734 {
2735         const struct cred *cred = current_cred();
2736
2737         return dentry_has_perm(cred, mnt, dentry, FILE__GETATTR);
2738 }
2739
2740 static int selinux_inode_setotherxattr(struct dentry *dentry, const char *name)
2741 {
2742         const struct cred *cred = current_cred();
2743
2744         if (!strncmp(name, XATTR_SECURITY_PREFIX,
2745                      sizeof XATTR_SECURITY_PREFIX - 1)) {
2746                 if (!strcmp(name, XATTR_NAME_CAPS)) {
2747                         if (!capable(CAP_SETFCAP))
2748                                 return -EPERM;
2749                 } else if (!capable(CAP_SYS_ADMIN)) {
2750                         /* A different attribute in the security namespace.
2751                            Restrict to administrator. */
2752                         return -EPERM;
2753                 }
2754         }
2755
2756         /* Not an attribute we recognize, so just check the
2757            ordinary setattr permission. */
2758         return dentry_has_perm(cred, NULL, dentry, FILE__SETATTR);
2759 }
2760
2761 static int selinux_inode_setxattr(struct dentry *dentry, const char *name,
2762                                   const void *value, size_t size, int flags)
2763 {
2764         struct inode *inode = dentry->d_inode;
2765         struct inode_security_struct *isec = inode->i_security;
2766         struct superblock_security_struct *sbsec;
2767         struct avc_audit_data ad;
2768         u32 newsid, sid = current_sid();
2769         int rc = 0;
2770
2771         if (strcmp(name, XATTR_NAME_SELINUX))
2772                 return selinux_inode_setotherxattr(dentry, name);
2773
2774         sbsec = inode->i_sb->s_security;
2775         if (!(sbsec->flags & SE_SBLABELSUPP))
2776                 return -EOPNOTSUPP;
2777
2778         if (!is_owner_or_cap(inode))
2779                 return -EPERM;
2780
2781         AVC_AUDIT_DATA_INIT(&ad, FS);
2782         ad.u.fs.path.dentry = dentry;
2783
2784         rc = avc_has_perm(sid, isec->sid, isec->sclass,
2785                           FILE__RELABELFROM, &ad);
2786         if (rc)
2787                 return rc;
2788
2789         rc = security_context_to_sid(value, size, &newsid);
2790         if (rc == -EINVAL) {
2791                 if (!capable(CAP_MAC_ADMIN))
2792                         return rc;
2793                 rc = security_context_to_sid_force(value, size, &newsid);
2794         }
2795         if (rc)
2796                 return rc;
2797
2798         rc = avc_has_perm(sid, newsid, isec->sclass,
2799                           FILE__RELABELTO, &ad);
2800         if (rc)
2801                 return rc;
2802
2803         rc = security_validate_transition(isec->sid, newsid, sid,
2804                                           isec->sclass);
2805         if (rc)
2806                 return rc;
2807
2808         return avc_has_perm(newsid,
2809                             sbsec->sid,
2810                             SECCLASS_FILESYSTEM,
2811                             FILESYSTEM__ASSOCIATE,
2812                             &ad);
2813 }
2814
2815 static void selinux_inode_post_setxattr(struct dentry *dentry, const char *name,
2816                                         const void *value, size_t size,
2817                                         int flags)
2818 {
2819         struct inode *inode = dentry->d_inode;
2820         struct inode_security_struct *isec = inode->i_security;
2821         u32 newsid;
2822         int rc;
2823
2824         if (strcmp(name, XATTR_NAME_SELINUX)) {
2825                 /* Not an attribute we recognize, so nothing to do. */
2826                 return;
2827         }
2828
2829         rc = security_context_to_sid_force(value, size, &newsid);
2830         if (rc) {
2831                 printk(KERN_ERR "SELinux:  unable to map context to SID"
2832                        "for (%s, %lu), rc=%d\n",
2833                        inode->i_sb->s_id, inode->i_ino, -rc);
2834                 return;
2835         }
2836
2837         isec->sid = newsid;
2838         return;
2839 }
2840
2841 static int selinux_inode_getxattr(struct dentry *dentry, const char *name)
2842 {
2843         const struct cred *cred = current_cred();
2844
2845         return dentry_has_perm(cred, NULL, dentry, FILE__GETATTR);
2846 }
2847
2848 static int selinux_inode_listxattr(struct dentry *dentry)
2849 {
2850         const struct cred *cred = current_cred();
2851
2852         return dentry_has_perm(cred, NULL, dentry, FILE__GETATTR);
2853 }
2854
2855 static int selinux_inode_removexattr(struct dentry *dentry, const char *name)
2856 {
2857         if (strcmp(name, XATTR_NAME_SELINUX))
2858                 return selinux_inode_setotherxattr(dentry, name);
2859
2860         /* No one is allowed to remove a SELinux security label.
2861            You can change the label, but all data must be labeled. */
2862         return -EACCES;
2863 }
2864
2865 /*
2866  * Copy the inode security context value to the user.
2867  *
2868  * Permission check is handled by selinux_inode_getxattr hook.
2869  */
2870 static int selinux_inode_getsecurity(const struct inode *inode, const char *name, void **buffer, bool alloc)
2871 {
2872         u32 size;
2873         int error;
2874         char *context = NULL;
2875         struct inode_security_struct *isec = inode->i_security;
2876
2877         if (strcmp(name, XATTR_SELINUX_SUFFIX))
2878                 return -EOPNOTSUPP;
2879
2880         /*
2881          * If the caller has CAP_MAC_ADMIN, then get the raw context
2882          * value even if it is not defined by current policy; otherwise,
2883          * use the in-core value under current policy.
2884          * Use the non-auditing forms of the permission checks since
2885          * getxattr may be called by unprivileged processes commonly
2886          * and lack of permission just means that we fall back to the
2887          * in-core context value, not a denial.
2888          */
2889         error = selinux_capable(current, current_cred(), CAP_MAC_ADMIN,
2890                                 SECURITY_CAP_NOAUDIT);
2891         if (!error)
2892                 error = security_sid_to_context_force(isec->sid, &context,
2893                                                       &size);
2894         else
2895                 error = security_sid_to_context(isec->sid, &context, &size);
2896         if (error)
2897                 return error;
2898         error = size;
2899         if (alloc) {
2900                 *buffer = context;
2901                 goto out_nofree;
2902         }
2903         kfree(context);
2904 out_nofree:
2905         return error;
2906 }
2907
2908 static int selinux_inode_setsecurity(struct inode *inode, const char *name,
2909                                      const void *value, size_t size, int flags)
2910 {
2911         struct inode_security_struct *isec = inode->i_security;
2912         u32 newsid;
2913         int rc;
2914
2915         if (strcmp(name, XATTR_SELINUX_SUFFIX))
2916                 return -EOPNOTSUPP;
2917
2918         if (!value || !size)
2919                 return -EACCES;
2920
2921         rc = security_context_to_sid((void *)value, size, &newsid);
2922         if (rc)
2923                 return rc;
2924
2925         isec->sid = newsid;
2926         return 0;
2927 }
2928
2929 static int selinux_inode_listsecurity(struct inode *inode, char *buffer, size_t buffer_size)
2930 {
2931         const int len = sizeof(XATTR_NAME_SELINUX);
2932         if (buffer && len <= buffer_size)
2933                 memcpy(buffer, XATTR_NAME_SELINUX, len);
2934         return len;
2935 }
2936
2937 static int selinux_inode_need_killpriv(struct dentry *dentry)
2938 {
2939         return secondary_ops->inode_need_killpriv(dentry);
2940 }
2941
2942 static int selinux_inode_killpriv(struct dentry *dentry)
2943 {
2944         return secondary_ops->inode_killpriv(dentry);
2945 }
2946
2947 static void selinux_inode_getsecid(const struct inode *inode, u32 *secid)
2948 {
2949         struct inode_security_struct *isec = inode->i_security;
2950         *secid = isec->sid;
2951 }
2952
2953 /* file security operations */
2954
2955 static int selinux_revalidate_file_permission(struct file *file, int mask)
2956 {
2957         const struct cred *cred = current_cred();
2958         int rc;
2959         struct inode *inode = file->f_path.dentry->d_inode;
2960
2961         if (!mask) {
2962                 /* No permission to check.  Existence test. */
2963                 return 0;
2964         }
2965
2966         /* file_mask_to_av won't add FILE__WRITE if MAY_APPEND is set */
2967         if ((file->f_flags & O_APPEND) && (mask & MAY_WRITE))
2968                 mask |= MAY_APPEND;
2969
2970         rc = file_has_perm(cred, file,
2971                            file_mask_to_av(inode->i_mode, mask));
2972         if (rc)
2973                 return rc;
2974
2975         return selinux_netlbl_inode_permission(inode, mask);
2976 }
2977
2978 static int selinux_file_permission(struct file *file, int mask)
2979 {
2980         struct inode *inode = file->f_path.dentry->d_inode;
2981         struct file_security_struct *fsec = file->f_security;
2982         struct inode_security_struct *isec = inode->i_security;
2983         u32 sid = current_sid();
2984
2985         if (!mask) {
2986                 /* No permission to check.  Existence test. */
2987                 return 0;
2988         }
2989
2990         if (sid == fsec->sid && fsec->isid == isec->sid
2991             && fsec->pseqno == avc_policy_seqno())
2992                 return selinux_netlbl_inode_permission(inode, mask);
2993
2994         return selinux_revalidate_file_permission(file, mask);
2995 }
2996
2997 static int selinux_file_alloc_security(struct file *file)
2998 {
2999         return file_alloc_security(file);
3000 }
3001
3002 static void selinux_file_free_security(struct file *file)
3003 {
3004         file_free_security(file);
3005 }
3006
3007 static int selinux_file_ioctl(struct file *file, unsigned int cmd,
3008                               unsigned long arg)
3009 {
3010         const struct cred *cred = current_cred();
3011         u32 av = 0;
3012
3013         if (_IOC_DIR(cmd) & _IOC_WRITE)
3014                 av |= FILE__WRITE;
3015         if (_IOC_DIR(cmd) & _IOC_READ)
3016                 av |= FILE__READ;
3017         if (!av)
3018                 av = FILE__IOCTL;
3019
3020         return file_has_perm(cred, file, av);
3021 }
3022
3023 static int file_map_prot_check(struct file *file, unsigned long prot, int shared)
3024 {
3025         const struct cred *cred = current_cred();
3026         int rc = 0;
3027
3028 #ifndef CONFIG_PPC32
3029         if ((prot & PROT_EXEC) && (!file || (!shared && (prot & PROT_WRITE)))) {
3030                 /*
3031                  * We are making executable an anonymous mapping or a
3032                  * private file mapping that will also be writable.
3033                  * This has an additional check.
3034                  */
3035                 rc = cred_has_perm(cred, cred, PROCESS__EXECMEM);
3036                 if (rc)
3037                         goto error;
3038         }
3039 #endif
3040
3041         if (file) {
3042                 /* read access is always possible with a mapping */
3043                 u32 av = FILE__READ;
3044
3045                 /* write access only matters if the mapping is shared */
3046                 if (shared && (prot & PROT_WRITE))
3047                         av |= FILE__WRITE;
3048
3049                 if (prot & PROT_EXEC)
3050                         av |= FILE__EXECUTE;
3051
3052                 return file_has_perm(cred, file, av);
3053         }
3054
3055 error:
3056         return rc;
3057 }
3058
3059 static int selinux_file_mmap(struct file *file, unsigned long reqprot,
3060                              unsigned long prot, unsigned long flags,
3061                              unsigned long addr, unsigned long addr_only)
3062 {
3063         int rc = 0;
3064         u32 sid = current_sid();
3065
3066         if (addr < mmap_min_addr)
3067                 rc = avc_has_perm(sid, sid, SECCLASS_MEMPROTECT,
3068                                   MEMPROTECT__MMAP_ZERO, NULL);
3069         if (rc || addr_only)
3070                 return rc;
3071
3072         if (selinux_checkreqprot)
3073                 prot = reqprot;
3074
3075         return file_map_prot_check(file, prot,
3076                                    (flags & MAP_TYPE) == MAP_SHARED);
3077 }
3078
3079 static int selinux_file_mprotect(struct vm_area_struct *vma,
3080                                  unsigned long reqprot,
3081                                  unsigned long prot)
3082 {
3083         const struct cred *cred = current_cred();
3084         int rc;
3085
3086         rc = secondary_ops->file_mprotect(vma, reqprot, prot);
3087         if (rc)
3088                 return rc;
3089
3090         if (selinux_checkreqprot)
3091                 prot = reqprot;
3092
3093 #ifndef CONFIG_PPC32
3094         if ((prot & PROT_EXEC) && !(vma->vm_flags & VM_EXEC)) {
3095                 rc = 0;
3096                 if (vma->vm_start >= vma->vm_mm->start_brk &&
3097                     vma->vm_end <= vma->vm_mm->brk) {
3098                         rc = cred_has_perm(cred, cred, PROCESS__EXECHEAP);
3099                 } else if (!vma->vm_file &&
3100                            vma->vm_start <= vma->vm_mm->start_stack &&
3101                            vma->vm_end >= vma->vm_mm->start_stack) {
3102                         rc = current_has_perm(current, PROCESS__EXECSTACK);
3103                 } else if (vma->vm_file && vma->anon_vma) {
3104                         /*
3105                          * We are making executable a file mapping that has
3106                          * had some COW done. Since pages might have been
3107                          * written, check ability to execute the possibly
3108                          * modified content.  This typically should only
3109                          * occur for text relocations.
3110                          */
3111                         rc = file_has_perm(cred, vma->vm_file, FILE__EXECMOD);
3112                 }
3113                 if (rc)
3114                         return rc;
3115         }
3116 #endif
3117
3118         return file_map_prot_check(vma->vm_file, prot, vma->vm_flags&VM_SHARED);
3119 }
3120
3121 static int selinux_file_lock(struct file *file, unsigned int cmd)
3122 {
3123         const struct cred *cred = current_cred();
3124
3125         return file_has_perm(cred, file, FILE__LOCK);
3126 }
3127
3128 static int selinux_file_fcntl(struct file *file, unsigned int cmd,
3129                               unsigned long arg)
3130 {
3131         const struct cred *cred = current_cred();
3132         int err = 0;
3133
3134         switch (cmd) {
3135         case F_SETFL:
3136                 if (!file->f_path.dentry || !file->f_path.dentry->d_inode) {
3137                         err = -EINVAL;
3138                         break;
3139                 }
3140
3141                 if ((file->f_flags & O_APPEND) && !(arg & O_APPEND)) {
3142                         err = file_has_perm(cred, file, FILE__WRITE);
3143                         break;
3144                 }
3145                 /* fall through */
3146         case F_SETOWN:
3147         case F_SETSIG:
3148         case F_GETFL:
3149         case F_GETOWN:
3150         case F_GETSIG:
3151                 /* Just check FD__USE permission */
3152                 err = file_has_perm(cred, file, 0);
3153                 break;
3154         case F_GETLK:
3155         case F_SETLK:
3156         case F_SETLKW:
3157 #if BITS_PER_LONG == 32
3158         case F_GETLK64:
3159         case F_SETLK64:
3160         case F_SETLKW64:
3161 #endif
3162                 if (!file->f_path.dentry || !file->f_path.dentry->d_inode) {
3163                         err = -EINVAL;
3164                         break;
3165                 }
3166                 err = file_has_perm(cred, file, FILE__LOCK);
3167                 break;
3168         }
3169
3170         return err;
3171 }
3172
3173 static int selinux_file_set_fowner(struct file *file)
3174 {
3175         struct file_security_struct *fsec;
3176
3177         fsec = file->f_security;
3178         fsec->fown_sid = current_sid();
3179
3180         return 0;
3181 }
3182
3183 static int selinux_file_send_sigiotask(struct task_struct *tsk,
3184                                        struct fown_struct *fown, int signum)
3185 {
3186         struct file *file;
3187         u32 sid = current_sid();
3188         u32 perm;
3189         struct file_security_struct *fsec;
3190
3191         /* struct fown_struct is never outside the context of a struct file */
3192         file = container_of(fown, struct file, f_owner);
3193
3194         fsec = file->f_security;
3195
3196         if (!signum)
3197                 perm = signal_to_av(SIGIO); /* as per send_sigio_to_task */
3198         else
3199                 perm = signal_to_av(signum);
3200
3201         return avc_has_perm(fsec->fown_sid, sid,
3202                             SECCLASS_PROCESS, perm, NULL);
3203 }
3204
3205 static int selinux_file_receive(struct file *file)
3206 {
3207         const struct cred *cred = current_cred();
3208
3209         return file_has_perm(cred, file, file_to_av(file));
3210 }
3211
3212 static int selinux_dentry_open(struct file *file, const struct cred *cred)
3213 {
3214         struct file_security_struct *fsec;
3215         struct inode *inode;
3216         struct inode_security_struct *isec;
3217
3218         inode = file->f_path.dentry->d_inode;
3219         fsec = file->f_security;
3220         isec = inode->i_security;
3221         /*
3222          * Save inode label and policy sequence number
3223          * at open-time so that selinux_file_permission
3224          * can determine whether revalidation is necessary.
3225          * Task label is already saved in the file security
3226          * struct as its SID.
3227          */
3228         fsec->isid = isec->sid;
3229         fsec->pseqno = avc_policy_seqno();
3230         /*
3231          * Since the inode label or policy seqno may have changed
3232          * between the selinux_inode_permission check and the saving
3233          * of state above, recheck that access is still permitted.
3234          * Otherwise, access might never be revalidated against the
3235          * new inode label or new policy.
3236          * This check is not redundant - do not remove.
3237          */
3238         return inode_has_perm(cred, inode, open_file_to_av(file), NULL);
3239 }
3240
3241 /* task security operations */
3242
3243 static int selinux_task_create(unsigned long clone_flags)
3244 {
3245         int rc;
3246
3247         rc = secondary_ops->task_create(clone_flags);
3248         if (rc)
3249                 return rc;
3250
3251         return current_has_perm(current, PROCESS__FORK);
3252 }
3253
3254 /*
3255  * detach and free the LSM part of a set of credentials
3256  */
3257 static void selinux_cred_free(struct cred *cred)
3258 {
3259         struct task_security_struct *tsec = cred->security;
3260         cred->security = NULL;
3261         kfree(tsec);
3262 }
3263
3264 /*
3265  * prepare a new set of credentials for modification
3266  */
3267 static int selinux_cred_prepare(struct cred *new, const struct cred *old,
3268                                 gfp_t gfp)
3269 {
3270         const struct task_security_struct *old_tsec;
3271         struct task_security_struct *tsec;
3272
3273         old_tsec = old->security;
3274
3275         tsec = kmemdup(old_tsec, sizeof(struct task_security_struct), gfp);
3276         if (!tsec)
3277                 return -ENOMEM;
3278
3279         new->security = tsec;
3280         return 0;
3281 }
3282
3283 /*
3284  * commit new credentials
3285  */
3286 static void selinux_cred_commit(struct cred *new, const struct cred *old)
3287 {
3288         secondary_ops->cred_commit(new, old);
3289 }
3290
3291 /*
3292  * set the security data for a kernel service
3293  * - all the creation contexts are set to unlabelled
3294  */
3295 static int selinux_kernel_act_as(struct cred *new, u32 secid)
3296 {
3297         struct task_security_struct *tsec = new->security;
3298         u32 sid = current_sid();
3299         int ret;
3300
3301         ret = avc_has_perm(sid, secid,
3302                            SECCLASS_KERNEL_SERVICE,
3303                            KERNEL_SERVICE__USE_AS_OVERRIDE,
3304                            NULL);
3305         if (ret == 0) {
3306                 tsec->sid = secid;
3307                 tsec->create_sid = 0;
3308                 tsec->keycreate_sid = 0;
3309                 tsec->sockcreate_sid = 0;
3310         }
3311         return ret;
3312 }
3313
3314 /*
3315  * set the file creation context in a security record to the same as the
3316  * objective context of the specified inode
3317  */
3318 static int selinux_kernel_create_files_as(struct cred *new, struct inode *inode)
3319 {
3320         struct inode_security_struct *isec = inode->i_security;
3321         struct task_security_struct *tsec = new->security;
3322         u32 sid = current_sid();
3323         int ret;
3324
3325         ret = avc_has_perm(sid, isec->sid,
3326                            SECCLASS_KERNEL_SERVICE,
3327                            KERNEL_SERVICE__CREATE_FILES_AS,
3328                            NULL);
3329
3330         if (ret == 0)
3331                 tsec->create_sid = isec->sid;
3332         return 0;
3333 }
3334
3335 static int selinux_task_setuid(uid_t id0, uid_t id1, uid_t id2, int flags)
3336 {
3337         /* Since setuid only affects the current process, and
3338            since the SELinux controls are not based on the Linux
3339            identity attributes, SELinux does not need to control
3340            this operation.  However, SELinux does control the use
3341            of the CAP_SETUID and CAP_SETGID capabilities using the
3342            capable hook. */
3343         return 0;
3344 }
3345
3346 static int selinux_task_fix_setuid(struct cred *new, const struct cred *old,
3347                                    int flags)
3348 {
3349         return secondary_ops->task_fix_setuid(new, old, flags);
3350 }
3351
3352 static int selinux_task_setgid(gid_t id0, gid_t id1, gid_t id2, int flags)
3353 {
3354         /* See the comment for setuid above. */
3355         return 0;
3356 }
3357
3358 static int selinux_task_setpgid(struct task_struct *p, pid_t pgid)
3359 {
3360         return current_has_perm(p, PROCESS__SETPGID);
3361 }
3362
3363 static int selinux_task_getpgid(struct task_struct *p)
3364 {
3365         return current_has_perm(p, PROCESS__GETPGID);
3366 }
3367
3368 static int selinux_task_getsid(struct task_struct *p)
3369 {
3370         return current_has_perm(p, PROCESS__GETSESSION);
3371 }
3372
3373 static void selinux_task_getsecid(struct task_struct *p, u32 *secid)
3374 {
3375         *secid = task_sid(p);
3376 }
3377
3378 static int selinux_task_setgroups(struct group_info *group_info)
3379 {
3380         /* See the comment for setuid above. */
3381         return 0;
3382 }
3383
3384 static int selinux_task_setnice(struct task_struct *p, int nice)
3385 {
3386         int rc;
3387
3388         rc = secondary_ops->task_setnice(p, nice);
3389         if (rc)
3390                 return rc;
3391
3392         return current_has_perm(p, PROCESS__SETSCHED);
3393 }
3394
3395 static int selinux_task_setioprio(struct task_struct *p, int ioprio)
3396 {
3397         int rc;
3398
3399         rc = secondary_ops->task_setioprio(p, ioprio);
3400         if (rc)
3401                 return rc;
3402
3403         return current_has_perm(p, PROCESS__SETSCHED);
3404 }
3405
3406 static int selinux_task_getioprio(struct task_struct *p)
3407 {
3408         return current_has_perm(p, PROCESS__GETSCHED);
3409 }
3410
3411 static int selinux_task_setrlimit(unsigned int resource, struct rlimit *new_rlim)
3412 {
3413         struct rlimit *old_rlim = current->signal->rlim + resource;
3414         int rc;
3415
3416         rc = secondary_ops->task_setrlimit(resource, new_rlim);
3417         if (rc)
3418                 return rc;
3419
3420         /* Control the ability to change the hard limit (whether
3421            lowering or raising it), so that the hard limit can
3422            later be used as a safe reset point for the soft limit
3423            upon context transitions.  See selinux_bprm_committing_creds. */
3424         if (old_rlim->rlim_max != new_rlim->rlim_max)
3425                 return current_has_perm(current, PROCESS__SETRLIMIT);
3426
3427         return 0;
3428 }
3429
3430 static int selinux_task_setscheduler(struct task_struct *p, int policy, struct sched_param *lp)
3431 {
3432         int rc;
3433
3434         rc = secondary_ops->task_setscheduler(p, policy, lp);
3435         if (rc)
3436                 return rc;
3437
3438         return current_has_perm(p, PROCESS__SETSCHED);
3439 }
3440
3441 static int selinux_task_getscheduler(struct task_struct *p)
3442 {
3443         return current_has_perm(p, PROCESS__GETSCHED);
3444 }
3445
3446 static int selinux_task_movememory(struct task_struct *p)
3447 {
3448         return current_has_perm(p, PROCESS__SETSCHED);
3449 }
3450
3451 static int selinux_task_kill(struct task_struct *p, struct siginfo *info,
3452                                 int sig, u32 secid)
3453 {
3454         u32 perm;
3455         int rc;
3456
3457         rc = secondary_ops->task_kill(p, info, sig, secid);
3458         if (rc)
3459                 return rc;
3460
3461         if (!sig)
3462                 perm = PROCESS__SIGNULL; /* null signal; existence test */
3463         else
3464                 perm = signal_to_av(sig);
3465         if (secid)
3466                 rc = avc_has_perm(secid, task_sid(p),
3467                                   SECCLASS_PROCESS, perm, NULL);
3468         else
3469                 rc = current_has_perm(p, perm);
3470         return rc;
3471 }
3472
3473 static int selinux_task_prctl(int option,
3474                               unsigned long arg2,
3475                               unsigned long arg3,
3476                               unsigned long arg4,
3477                               unsigned long arg5)
3478 {
3479         /* The current prctl operations do not appear to require
3480            any SELinux controls since they merely observe or modify
3481            the state of the current process. */
3482         return secondary_ops->task_prctl(option, arg2, arg3, arg4, arg5);
3483 }
3484
3485 static int selinux_task_wait(struct task_struct *p)
3486 {
3487         return task_has_perm(p, current, PROCESS__SIGCHLD);
3488 }
3489
3490 static void selinux_task_to_inode(struct task_struct *p,
3491                                   struct inode *inode)
3492 {
3493         struct inode_security_struct *isec = inode->i_security;
3494         u32 sid = task_sid(p);
3495
3496         isec->sid = sid;
3497         isec->initialized = 1;
3498 }
3499
3500 /* Returns error only if unable to parse addresses */
3501 static int selinux_parse_skb_ipv4(struct sk_buff *skb,
3502                         struct avc_audit_data *ad, u8 *proto)
3503 {
3504         int offset, ihlen, ret = -EINVAL;
3505         struct iphdr _iph, *ih;
3506
3507         offset = skb_network_offset(skb);
3508         ih = skb_header_pointer(skb, offset, sizeof(_iph), &_iph);
3509         if (ih == NULL)
3510                 goto out;
3511
3512         ihlen = ih->ihl * 4;
3513         if (ihlen < sizeof(_iph))
3514                 goto out;
3515
3516         ad->u.net.v4info.saddr = ih->saddr;
3517         ad->u.net.v4info.daddr = ih->daddr;
3518         ret = 0;
3519
3520         if (proto)
3521                 *proto = ih->protocol;
3522
3523         switch (ih->protocol) {
3524         case IPPROTO_TCP: {
3525                 struct tcphdr _tcph, *th;
3526
3527                 if (ntohs(ih->frag_off) & IP_OFFSET)
3528                         break;
3529
3530                 offset += ihlen;
3531                 th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph);
3532                 if (th == NULL)
3533                         break;
3534
3535                 ad->u.net.sport = th->source;
3536                 ad->u.net.dport = th->dest;
3537                 break;
3538         }
3539
3540         case IPPROTO_UDP: {
3541                 struct udphdr _udph, *uh;
3542
3543                 if (ntohs(ih->frag_off) & IP_OFFSET)
3544                         break;
3545
3546                 offset += ihlen;
3547                 uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph);
3548                 if (uh == NULL)
3549                         break;
3550
3551                 ad->u.net.sport = uh->source;
3552                 ad->u.net.dport = uh->dest;
3553                 break;
3554         }
3555
3556         case IPPROTO_DCCP: {
3557                 struct dccp_hdr _dccph, *dh;
3558
3559                 if (ntohs(ih->frag_off) & IP_OFFSET)
3560                         break;
3561
3562                 offset += ihlen;
3563                 dh = skb_header_pointer(skb, offset, sizeof(_dccph), &_dccph);
3564                 if (dh == NULL)
3565                         break;
3566
3567                 ad->u.net.sport = dh->dccph_sport;
3568                 ad->u.net.dport = dh->dccph_dport;
3569                 break;
3570         }
3571
3572         default:
3573                 break;
3574         }
3575 out:
3576         return ret;
3577 }
3578
3579 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
3580
3581 /* Returns error only if unable to parse addresses */
3582 static int selinux_parse_skb_ipv6(struct sk_buff *skb,
3583                         struct avc_audit_data *ad, u8 *proto)
3584 {
3585         u8 nexthdr;
3586         int ret = -EINVAL, offset;
3587         struct ipv6hdr _ipv6h, *ip6;
3588
3589         offset = skb_network_offset(skb);
3590         ip6 = skb_header_pointer(skb, offset, sizeof(_ipv6h), &_ipv6h);
3591         if (ip6 == NULL)
3592                 goto out;
3593
3594         ipv6_addr_copy(&ad->u.net.v6info.saddr, &ip6->saddr);
3595         ipv6_addr_copy(&ad->u.net.v6info.daddr, &ip6->daddr);
3596         ret = 0;
3597
3598         nexthdr = ip6->nexthdr;
3599         offset += sizeof(_ipv6h);
3600         offset = ipv6_skip_exthdr(skb, offset, &nexthdr);
3601         if (offset < 0)
3602                 goto out;
3603
3604         if (proto)
3605                 *proto = nexthdr;
3606
3607         switch (nexthdr) {
3608         case IPPROTO_TCP: {
3609                 struct tcphdr _tcph, *th;
3610
3611                 th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph);
3612                 if (th == NULL)
3613                         break;
3614
3615                 ad->u.net.sport = th->source;
3616                 ad->u.net.dport = th->dest;
3617                 break;
3618         }
3619
3620         case IPPROTO_UDP: {
3621                 struct udphdr _udph, *uh;
3622
3623                 uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph);
3624                 if (uh == NULL)
3625                         break;
3626
3627                 ad->u.net.sport = uh->source;
3628                 ad->u.net.dport = uh->dest;
3629                 break;
3630         }
3631
3632         case IPPROTO_DCCP: {
3633                 struct dccp_hdr _dccph, *dh;
3634
3635                 dh = skb_header_pointer(skb, offset, sizeof(_dccph), &_dccph);
3636                 if (dh == NULL)
3637                         break;
3638
3639                 ad->u.net.sport = dh->dccph_sport;
3640                 ad->u.net.dport = dh->dccph_dport;
3641                 break;
3642         }
3643
3644         /* includes fragments */
3645         default:
3646                 break;
3647         }
3648 out:
3649         return ret;
3650 }
3651
3652 #endif /* IPV6 */
3653
3654 static int selinux_parse_skb(struct sk_buff *skb, struct avc_audit_data *ad,
3655                              char **_addrp, int src, u8 *proto)
3656 {
3657         char *addrp;
3658         int ret;
3659
3660         switch (ad->u.net.family) {
3661         case PF_INET:
3662                 ret = selinux_parse_skb_ipv4(skb, ad, proto);
3663                 if (ret)
3664                         goto parse_error;
3665                 addrp = (char *)(src ? &ad->u.net.v4info.saddr :
3666                                        &ad->u.net.v4info.daddr);
3667                 goto okay;
3668
3669 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
3670         case PF_INET6:
3671                 ret = selinux_parse_skb_ipv6(skb, ad, proto);
3672                 if (ret)
3673                         goto parse_error;
3674                 addrp = (char *)(src ? &ad->u.net.v6info.saddr :
3675                                        &ad->u.net.v6info.daddr);
3676                 goto okay;
3677 #endif  /* IPV6 */
3678         default:
3679                 addrp = NULL;
3680                 goto okay;
3681         }
3682
3683 parse_error:
3684         printk(KERN_WARNING
3685                "SELinux: failure in selinux_parse_skb(),"
3686                " unable to parse packet\n");
3687         return ret;
3688
3689 okay:
3690         if (_addrp)
3691                 *_addrp = addrp;
3692         return 0;
3693 }
3694
3695 /**
3696  * selinux_skb_peerlbl_sid - Determine the peer label of a packet
3697  * @skb: the packet
3698  * @family: protocol family
3699  * @sid: the packet's peer label SID
3700  *
3701  * Description:
3702  * Check the various different forms of network peer labeling and determine
3703  * the peer label/SID for the packet; most of the magic actually occurs in
3704  * the security server function security_net_peersid_cmp().  The function
3705  * returns zero if the value in @sid is valid (although it may be SECSID_NULL)
3706  * or -EACCES if @sid is invalid due to inconsistencies with the different
3707  * peer labels.
3708  *
3709  */
3710 static int selinux_skb_peerlbl_sid(struct sk_buff *skb, u16 family, u32 *sid)
3711 {
3712         int err;
3713         u32 xfrm_sid;
3714         u32 nlbl_sid;
3715         u32 nlbl_type;
3716
3717         selinux_skb_xfrm_sid(skb, &xfrm_sid);
3718         selinux_netlbl_skbuff_getsid(skb, family, &nlbl_type, &nlbl_sid);
3719
3720         err = security_net_peersid_resolve(nlbl_sid, nlbl_type, xfrm_sid, sid);
3721         if (unlikely(err)) {
3722                 printk(KERN_WARNING
3723                        "SELinux: failure in selinux_skb_peerlbl_sid(),"
3724                        " unable to determine packet's peer label\n");
3725                 return -EACCES;
3726         }
3727
3728         return 0;
3729 }
3730
3731 /* socket security operations */
3732 static int socket_has_perm(struct task_struct *task, struct socket *sock,
3733                            u32 perms)
3734 {
3735         struct inode_security_struct *isec;
3736         struct avc_audit_data ad;
3737         u32 sid;
3738         int err = 0;
3739
3740         isec = SOCK_INODE(sock)->i_security;
3741
3742         if (isec->sid == SECINITSID_KERNEL)
3743                 goto out;
3744         sid = task_sid(task);
3745
3746         AVC_AUDIT_DATA_INIT(&ad, NET);
3747         ad.u.net.sk = sock->sk;
3748         err = avc_has_perm(sid, isec->sid, isec->sclass, perms, &ad);
3749
3750 out:
3751         return err;
3752 }
3753
3754 static int selinux_socket_create(int family, int type,
3755                                  int protocol, int kern)
3756 {
3757         const struct cred *cred = current_cred();
3758         const struct task_security_struct *tsec = cred->security;
3759         u32 sid, newsid;
3760         u16 secclass;
3761         int err = 0;
3762
3763         if (kern)
3764                 goto out;
3765
3766         sid = tsec->sid;
3767         newsid = tsec->sockcreate_sid ?: sid;
3768
3769         secclass = socket_type_to_security_class(family, type, protocol);
3770         err = avc_has_perm(sid, newsid, secclass, SOCKET__CREATE, NULL);
3771
3772 out:
3773         return err;
3774 }
3775
3776 static int selinux_socket_post_create(struct socket *sock, int family,
3777                                       int type, int protocol, int kern)
3778 {
3779         const struct cred *cred = current_cred();
3780         const struct task_security_struct *tsec = cred->security;
3781         struct inode_security_struct *isec;
3782         struct sk_security_struct *sksec;
3783         u32 sid, newsid;
3784         int err = 0;
3785
3786         sid = tsec->sid;
3787         newsid = tsec->sockcreate_sid;
3788
3789         isec = SOCK_INODE(sock)->i_security;
3790
3791         if (kern)
3792                 isec->sid = SECINITSID_KERNEL;
3793         else if (newsid)
3794                 isec->sid = newsid;
3795         else
3796                 isec->sid = sid;
3797
3798         isec->sclass = socket_type_to_security_class(family, type, protocol);
3799         isec->initialized = 1;
3800
3801         if (sock->sk) {
3802                 sksec = sock->sk->sk_security;
3803                 sksec->sid = isec->sid;
3804                 sksec->sclass = isec->sclass;
3805                 err = selinux_netlbl_socket_post_create(sock);
3806         }
3807
3808         return err;
3809 }
3810
3811 /* Range of port numbers used to automatically bind.
3812    Need to determine whether we should perform a name_bind
3813    permission check between the socket and the port number. */
3814
3815 static int selinux_socket_bind(struct socket *sock, struct sockaddr *address, int addrlen)
3816 {
3817         u16 family;
3818         int err;
3819
3820         err = socket_has_perm(current, sock, SOCKET__BIND);
3821         if (err)
3822                 goto out;
3823
3824         /*
3825          * If PF_INET or PF_INET6, check name_bind permission for the port.
3826          * Multiple address binding for SCTP is not supported yet: we just
3827          * check the first address now.
3828          */
3829         family = sock->sk->sk_family;
3830         if (family == PF_INET || family == PF_INET6) {
3831                 char *addrp;
3832                 struct inode_security_struct *isec;
3833                 struct avc_audit_data ad;
3834                 struct sockaddr_in *addr4 = NULL;
3835                 struct sockaddr_in6 *addr6 = NULL;
3836                 unsigned short snum;
3837                 struct sock *sk = sock->sk;
3838                 u32 sid, node_perm;
3839
3840                 isec = SOCK_INODE(sock)->i_security;
3841
3842                 if (family == PF_INET) {
3843                         addr4 = (struct sockaddr_in *)address;
3844                         snum = ntohs(addr4->sin_port);
3845                         addrp = (char *)&addr4->sin_addr.s_addr;
3846                 } else {
3847                         addr6 = (struct sockaddr_in6 *)address;
3848                         snum = ntohs(addr6->sin6_port);
3849                         addrp = (char *)&addr6->sin6_addr.s6_addr;
3850                 }
3851
3852                 if (snum) {
3853                         int low, high;
3854
3855                         inet_get_local_port_range(&low, &high);
3856
3857                         if (snum < max(PROT_SOCK, low) || snum > high) {
3858                                 err = sel_netport_sid(sk->sk_protocol,
3859                                                       snum, &sid);
3860                                 if (err)
3861                                         goto out;
3862                                 AVC_AUDIT_DATA_INIT(&ad, NET);
3863                                 ad.u.net.sport = htons(snum);
3864                                 ad.u.net.family = family;
3865                                 err = avc_has_perm(isec->sid, sid,
3866                                                    isec->sclass,
3867                                                    SOCKET__NAME_BIND, &ad);
3868                                 if (err)
3869                                         goto out;
3870                         }
3871                 }
3872
3873                 switch (isec->sclass) {
3874                 case SECCLASS_TCP_SOCKET:
3875                         node_perm = TCP_SOCKET__NODE_BIND;
3876                         break;
3877
3878                 case SECCLASS_UDP_SOCKET:
3879                         node_perm = UDP_SOCKET__NODE_BIND;
3880                         break;
3881
3882                 case SECCLASS_DCCP_SOCKET:
3883                         node_perm = DCCP_SOCKET__NODE_BIND;
3884                         break;
3885
3886                 default:
3887                         node_perm = RAWIP_SOCKET__NODE_BIND;
3888                         break;
3889                 }
3890
3891                 err = sel_netnode_sid(addrp, family, &sid);
3892                 if (err)
3893                         goto out;
3894
3895                 AVC_AUDIT_DATA_INIT(&ad, NET);
3896                 ad.u.net.sport = htons(snum);
3897                 ad.u.net.family = family;
3898
3899                 if (family == PF_INET)
3900                         ad.u.net.v4info.saddr = addr4->sin_addr.s_addr;
3901                 else
3902                         ipv6_addr_copy(&ad.u.net.v6info.saddr, &addr6->sin6_addr);
3903
3904                 err = avc_has_perm(isec->sid, sid,
3905                                    isec->sclass, node_perm, &ad);
3906                 if (err)
3907                         goto out;
3908         }
3909 out:
3910         return err;
3911 }
3912
3913 static int selinux_socket_connect(struct socket *sock, struct sockaddr *address, int addrlen)
3914 {
3915         struct sock *sk = sock->sk;
3916         struct inode_security_struct *isec;
3917         int err;
3918
3919         err = socket_has_perm(current, sock, SOCKET__CONNECT);
3920         if (err)
3921                 return err;
3922
3923         /*
3924          * If a TCP or DCCP socket, check name_connect permission for the port.
3925          */
3926         isec = SOCK_INODE(sock)->i_security;
3927         if (isec->sclass == SECCLASS_TCP_SOCKET ||
3928             isec->sclass == SECCLASS_DCCP_SOCKET) {
3929                 struct avc_audit_data ad;
3930                 struct sockaddr_in *addr4 = NULL;
3931                 struct sockaddr_in6 *addr6 = NULL;
3932                 unsigned short snum;
3933                 u32 sid, perm;
3934
3935                 if (sk->sk_family == PF_INET) {
3936                         addr4 = (struct sockaddr_in *)address;
3937                         if (addrlen < sizeof(struct sockaddr_in))
3938                                 return -EINVAL;
3939                         snum = ntohs(addr4->sin_port);
3940                 } else {
3941                         addr6 = (struct sockaddr_in6 *)address;
3942                         if (addrlen < SIN6_LEN_RFC2133)
3943                                 return -EINVAL;
3944                         snum = ntohs(addr6->sin6_port);
3945                 }
3946
3947                 err = sel_netport_sid(sk->sk_protocol, snum, &sid);
3948                 if (err)
3949                         goto out;
3950
3951                 perm = (isec->sclass == SECCLASS_TCP_SOCKET) ?
3952                        TCP_SOCKET__NAME_CONNECT : DCCP_SOCKET__NAME_CONNECT;
3953
3954                 AVC_AUDIT_DATA_INIT(&ad, NET);
3955                 ad.u.net.dport = htons(snum);
3956                 ad.u.net.family = sk->sk_family;
3957                 err = avc_has_perm(isec->sid, sid, isec->sclass, perm, &ad);
3958                 if (err)
3959                         goto out;
3960         }
3961
3962         err = selinux_netlbl_socket_connect(sk, address);
3963
3964 out:
3965         return err;
3966 }
3967
3968 static int selinux_socket_listen(struct socket *sock, int backlog)
3969 {
3970         return socket_has_perm(current, sock, SOCKET__LISTEN);
3971 }
3972
3973 static int selinux_socket_accept(struct socket *sock, struct socket *newsock)
3974 {
3975         int err;
3976         struct inode_security_struct *isec;
3977         struct inode_security_struct *newisec;
3978
3979         err = socket_has_perm(current, sock, SOCKET__ACCEPT);
3980         if (err)
3981                 return err;
3982
3983         newisec = SOCK_INODE(newsock)->i_security;
3984
3985         isec = SOCK_INODE(sock)->i_security;
3986         newisec->sclass = isec->sclass;
3987         newisec->sid = isec->sid;
3988         newisec->initialized = 1;
3989
3990         return 0;
3991 }
3992
3993 static int selinux_socket_sendmsg(struct socket *sock, struct msghdr *msg,
3994                                   int size)
3995 {
3996         int rc;
3997
3998         rc = socket_has_perm(current, sock, SOCKET__WRITE);
3999         if (rc)
4000                 return rc;
4001
4002         return selinux_netlbl_inode_permission(SOCK_INODE(sock), MAY_WRITE);
4003 }
4004
4005 static int selinux_socket_recvmsg(struct socket *sock, struct msghdr *msg,
4006                                   int size, int flags)
4007 {
4008         return socket_has_perm(current, sock, SOCKET__READ);
4009 }
4010
4011 static int selinux_socket_getsockname(struct socket *sock)
4012 {
4013         return socket_has_perm(current, sock, SOCKET__GETATTR);
4014 }
4015
4016 static int selinux_socket_getpeername(struct socket *sock)
4017 {
4018         return socket_has_perm(current, sock, SOCKET__GETATTR);
4019 }
4020
4021 static int selinux_socket_setsockopt(struct socket *sock, int level, int optname)
4022 {
4023         int err;
4024
4025         err = socket_has_perm(current, sock, SOCKET__SETOPT);
4026         if (err)
4027                 return err;
4028
4029         return selinux_netlbl_socket_setsockopt(sock, level, optname);
4030 }
4031
4032 static int selinux_socket_getsockopt(struct socket *sock, int level,
4033                                      int optname)
4034 {
4035         return socket_has_perm(current, sock, SOCKET__GETOPT);
4036 }
4037
4038 static int selinux_socket_shutdown(struct socket *sock, int how)
4039 {
4040         return socket_has_perm(current, sock, SOCKET__SHUTDOWN);
4041 }
4042
4043 static int selinux_socket_unix_stream_connect(struct socket *sock,
4044                                               struct socket *other,
4045                                               struct sock *newsk)
4046 {
4047         struct sk_security_struct *ssec;
4048         struct inode_security_struct *isec;
4049         struct inode_security_struct *other_isec;
4050         struct avc_audit_data ad;
4051         int err;
4052
4053         err = secondary_ops->unix_stream_connect(sock, other, newsk);
4054         if (err)
4055                 return err;
4056
4057         isec = SOCK_INODE(sock)->i_security;
4058         other_isec = SOCK_INODE(other)->i_security;
4059
4060         AVC_AUDIT_DATA_INIT(&ad, NET);
4061         ad.u.net.sk = other->sk;
4062
4063         err = avc_has_perm(isec->sid, other_isec->sid,
4064                            isec->sclass,
4065                            UNIX_STREAM_SOCKET__CONNECTTO, &ad);
4066         if (err)
4067                 return err;
4068
4069         /* connecting socket */
4070         ssec = sock->sk->sk_security;
4071         ssec->peer_sid = other_isec->sid;
4072
4073         /* server child socket */
4074         ssec = newsk->sk_security;
4075         ssec->peer_sid = isec->sid;
4076         err = security_sid_mls_copy(other_isec->sid, ssec->peer_sid, &ssec->sid);
4077
4078         return err;
4079 }
4080
4081 static int selinux_socket_unix_may_send(struct socket *sock,
4082                                         struct socket *other)
4083 {
4084         struct inode_security_struct *isec;
4085         struct inode_security_struct *other_isec;
4086         struct avc_audit_data ad;
4087         int err;
4088
4089         isec = SOCK_INODE(sock)->i_security;
4090         other_isec = SOCK_INODE(other)->i_security;
4091
4092         AVC_AUDIT_DATA_INIT(&ad, NET);
4093         ad.u.net.sk = other->sk;
4094
4095         err = avc_has_perm(isec->sid, other_isec->sid,
4096                            isec->sclass, SOCKET__SENDTO, &ad);
4097         if (err)
4098                 return err;
4099
4100         return 0;
4101 }
4102
4103 static int selinux_inet_sys_rcv_skb(int ifindex, char *addrp, u16 family,
4104                                     u32 peer_sid,
4105                                     struct avc_audit_data *ad)
4106 {
4107         int err;
4108         u32 if_sid;
4109         u32 node_sid;
4110
4111         err = sel_netif_sid(ifindex, &if_sid);
4112         if (err)
4113                 return err;
4114         err = avc_has_perm(peer_sid, if_sid,
4115                            SECCLASS_NETIF, NETIF__INGRESS, ad);
4116         if (err)
4117                 return err;
4118
4119         err = sel_netnode_sid(addrp, family, &node_sid);
4120         if (err)
4121                 return err;
4122         return avc_has_perm(peer_sid, node_sid,
4123                             SECCLASS_NODE, NODE__RECVFROM, ad);
4124 }
4125
4126 static int selinux_sock_rcv_skb_iptables_compat(struct sock *sk,
4127                                                 struct sk_buff *skb,
4128                                                 struct avc_audit_data *ad,
4129                                                 u16 family,
4130                                                 char *addrp)
4131 {
4132         int err;
4133         struct sk_security_struct *sksec = sk->sk_security;
4134         u16 sk_class;
4135         u32 netif_perm, node_perm, recv_perm;
4136         u32 port_sid, node_sid, if_sid, sk_sid;
4137
4138         sk_sid = sksec->sid;
4139         sk_class = sksec->sclass;
4140
4141         switch (sk_class) {
4142         case SECCLASS_UDP_SOCKET:
4143                 netif_perm = NETIF__UDP_RECV;
4144                 node_perm = NODE__UDP_RECV;
4145                 recv_perm = UDP_SOCKET__RECV_MSG;
4146                 break;
4147         case SECCLASS_TCP_SOCKET:
4148                 netif_perm = NETIF__TCP_RECV;
4149                 node_perm = NODE__TCP_RECV;
4150                 recv_perm = TCP_SOCKET__RECV_MSG;
4151                 break;
4152         case SECCLASS_DCCP_SOCKET:
4153                 netif_perm = NETIF__DCCP_RECV;
4154                 node_perm = NODE__DCCP_RECV;
4155                 recv_perm = DCCP_SOCKET__RECV_MSG;
4156                 break;
4157         default:
4158                 netif_perm = NETIF__RAWIP_RECV;
4159                 node_perm = NODE__RAWIP_RECV;
4160                 recv_perm = 0;
4161                 break;
4162         }
4163
4164         err = sel_netif_sid(skb->iif, &if_sid);
4165         if (err)
4166                 return err;
4167         err = avc_has_perm(sk_sid, if_sid, SECCLASS_NETIF, netif_perm, ad);
4168         if (err)
4169                 return err;
4170
4171         err = sel_netnode_sid(addrp, family, &node_sid);
4172         if (err)
4173                 return err;
4174         err = avc_has_perm(sk_sid, node_sid, SECCLASS_NODE, node_perm, ad);
4175         if (err)
4176                 return err;
4177
4178         if (!recv_perm)
4179                 return 0;
4180         err = sel_netport_sid(sk->sk_protocol,
4181                               ntohs(ad->u.net.sport), &port_sid);
4182         if (unlikely(err)) {
4183                 printk(KERN_WARNING
4184                        "SELinux: failure in"
4185                        " selinux_sock_rcv_skb_iptables_compat(),"
4186                        " network port label not found\n");
4187                 return err;
4188         }
4189         return avc_has_perm(sk_sid, port_sid, sk_class, recv_perm, ad);
4190 }
4191
4192 static int selinux_sock_rcv_skb_compat(struct sock *sk, struct sk_buff *skb,
4193                                        u16 family)
4194 {
4195         int err = 0;
4196         struct sk_security_struct *sksec = sk->sk_security;
4197         u32 peer_sid;
4198         u32 sk_sid = sksec->sid;
4199         struct avc_audit_data ad;
4200         char *addrp;
4201
4202         AVC_AUDIT_DATA_INIT(&ad, NET);
4203         ad.u.net.netif = skb->iif;
4204         ad.u.net.family = family;
4205         err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL);
4206         if (err)
4207                 return err;
4208
4209         if (selinux_compat_net)
4210                 err = selinux_sock_rcv_skb_iptables_compat(sk, skb, &ad,
4211                                                            family, addrp);
4212         else if (selinux_secmark_enabled())
4213                 err = avc_has_perm(sk_sid, skb->secmark, SECCLASS_PACKET,
4214                                    PACKET__RECV, &ad);
4215         if (err)
4216                 return err;
4217
4218         if (selinux_policycap_netpeer) {
4219                 err = selinux_skb_peerlbl_sid(skb, family, &peer_sid);
4220                 if (err)
4221                         return err;
4222                 err = avc_has_perm(sk_sid, peer_sid,
4223                                    SECCLASS_PEER, PEER__RECV, &ad);
4224                 if (err)
4225                         selinux_netlbl_err(skb, err, 0);
4226         } else {
4227                 err = selinux_netlbl_sock_rcv_skb(sksec, skb, family, &ad);
4228                 if (err)
4229                         return err;
4230                 err = selinux_xfrm_sock_rcv_skb(sksec->sid, skb, &ad);
4231         }
4232
4233         return err;
4234 }
4235
4236 static int selinux_socket_sock_rcv_skb(struct sock *sk, struct sk_buff *skb)
4237 {
4238         int err;
4239         struct sk_security_struct *sksec = sk->sk_security;
4240         u16 family = sk->sk_family;
4241         u32 sk_sid = sksec->sid;
4242         struct avc_audit_data ad;
4243         char *addrp;
4244         u8 secmark_active;
4245         u8 peerlbl_active;
4246
4247         if (family != PF_INET && family != PF_INET6)
4248                 return 0;
4249
4250         /* Handle mapped IPv4 packets arriving via IPv6 sockets */
4251         if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
4252                 family = PF_INET;
4253
4254         /* If any sort of compatibility mode is enabled then handoff processing
4255          * to the selinux_sock_rcv_skb_compat() function to deal with the
4256          * special handling.  We do this in an attempt to keep this function
4257          * as fast and as clean as possible. */
4258         if (selinux_compat_net || !selinux_policycap_netpeer)
4259                 return selinux_sock_rcv_skb_compat(sk, skb, family);
4260
4261         secmark_active = selinux_secmark_enabled();
4262         peerlbl_active = netlbl_enabled() || selinux_xfrm_enabled();
4263         if (!secmark_active && !peerlbl_active)
4264                 return 0;
4265
4266         AVC_AUDIT_DATA_INIT(&ad, NET);
4267         ad.u.net.netif = skb->iif;
4268         ad.u.net.family = family;
4269         err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL);
4270         if (err)
4271                 return err;
4272
4273         if (peerlbl_active) {
4274                 u32 peer_sid;
4275
4276                 err = selinux_skb_peerlbl_sid(skb, family, &peer_sid);
4277                 if (err)
4278                         return err;
4279                 err = selinux_inet_sys_rcv_skb(skb->iif, addrp, family,
4280                                                peer_sid, &ad);
4281                 if (err) {
4282                         selinux_netlbl_err(skb, err, 0);
4283                         return err;
4284                 }
4285                 err = avc_has_perm(sk_sid, peer_sid, SECCLASS_PEER,
4286                                    PEER__RECV, &ad);
4287                 if (err)
4288                         selinux_netlbl_err(skb, err, 0);
4289         }
4290
4291         if (secmark_active) {
4292                 err = avc_has_perm(sk_sid, skb->secmark, SECCLASS_PACKET,
4293                                    PACKET__RECV, &ad);
4294                 if (err)
4295                         return err;
4296         }
4297
4298         return err;
4299 }
4300
4301 static int selinux_socket_getpeersec_stream(struct socket *sock, char __user *optval,
4302                                             int __user *optlen, unsigned len)
4303 {
4304         int err = 0;
4305         char *scontext;
4306         u32 scontext_len;
4307         struct sk_security_struct *ssec;
4308         struct inode_security_struct *isec;
4309         u32 peer_sid = SECSID_NULL;
4310
4311         isec = SOCK_INODE(sock)->i_security;
4312
4313         if (isec->sclass == SECCLASS_UNIX_STREAM_SOCKET ||
4314             isec->sclass == SECCLASS_TCP_SOCKET) {
4315                 ssec = sock->sk->sk_security;
4316                 peer_sid = ssec->peer_sid;
4317         }
4318         if (peer_sid == SECSID_NULL) {
4319                 err = -ENOPROTOOPT;
4320                 goto out;
4321         }
4322
4323         err = security_sid_to_context(peer_sid, &scontext, &scontext_len);
4324
4325         if (err)
4326                 goto out;
4327
4328         if (scontext_len > len) {
4329                 err = -ERANGE;
4330                 goto out_len;
4331         }
4332
4333         if (copy_to_user(optval, scontext, scontext_len))
4334                 err = -EFAULT;
4335
4336 out_len:
4337         if (put_user(scontext_len, optlen))
4338                 err = -EFAULT;
4339
4340         kfree(scontext);
4341 out:
4342         return err;
4343 }
4344
4345 static int selinux_socket_getpeersec_dgram(struct socket *sock, struct sk_buff *skb, u32 *secid)
4346 {
4347         u32 peer_secid = SECSID_NULL;
4348         u16 family;
4349
4350         if (skb && skb->protocol == htons(ETH_P_IP))
4351                 family = PF_INET;
4352         else if (skb && skb->protocol == htons(ETH_P_IPV6))
4353                 family = PF_INET6;
4354         else if (sock)
4355                 family = sock->sk->sk_family;
4356         else
4357                 goto out;
4358
4359         if (sock && family == PF_UNIX)
4360                 selinux_inode_getsecid(SOCK_INODE(sock), &peer_secid);
4361         else if (skb)
4362                 selinux_skb_peerlbl_sid(skb, family, &peer_secid);
4363
4364 out:
4365         *secid = peer_secid;
4366         if (peer_secid == SECSID_NULL)
4367                 return -EINVAL;
4368         return 0;
4369 }
4370
4371 static int selinux_sk_alloc_security(struct sock *sk, int family, gfp_t priority)
4372 {
4373         return sk_alloc_security(sk, family, priority);
4374 }
4375
4376 static void selinux_sk_free_security(struct sock *sk)
4377 {
4378         sk_free_security(sk);
4379 }
4380
4381 static void selinux_sk_clone_security(const struct sock *sk, struct sock *newsk)
4382 {
4383         struct sk_security_struct *ssec = sk->sk_security;
4384         struct sk_security_struct *newssec = newsk->sk_security;
4385
4386         newssec->sid = ssec->sid;
4387         newssec->peer_sid = ssec->peer_sid;
4388         newssec->sclass = ssec->sclass;
4389
4390         selinux_netlbl_sk_security_reset(newssec, newsk->sk_family);
4391 }
4392
4393 static void selinux_sk_getsecid(struct sock *sk, u32 *secid)
4394 {
4395         if (!sk)
4396                 *secid = SECINITSID_ANY_SOCKET;
4397         else {
4398                 struct sk_security_struct *sksec = sk->sk_security;
4399
4400                 *secid = sksec->sid;
4401         }
4402 }
4403
4404 static void selinux_sock_graft(struct sock *sk, struct socket *parent)
4405 {
4406         struct inode_security_struct *isec = SOCK_INODE(parent)->i_security;
4407         struct sk_security_struct *sksec = sk->sk_security;
4408
4409         if (sk->sk_family == PF_INET || sk->sk_family == PF_INET6 ||
4410             sk->sk_family == PF_UNIX)
4411                 isec->sid = sksec->sid;
4412         sksec->sclass = isec->sclass;
4413 }
4414
4415 static int selinux_inet_conn_request(struct sock *sk, struct sk_buff *skb,
4416                                      struct request_sock *req)
4417 {
4418         struct sk_security_struct *sksec = sk->sk_security;
4419         int err;
4420         u16 family = sk->sk_family;
4421         u32 newsid;
4422         u32 peersid;
4423
4424         /* handle mapped IPv4 packets arriving via IPv6 sockets */
4425         if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
4426                 family = PF_INET;
4427
4428         err = selinux_skb_peerlbl_sid(skb, family, &peersid);
4429         if (err)
4430                 return err;
4431         if (peersid == SECSID_NULL) {
4432                 req->secid = sksec->sid;
4433                 req->peer_secid = SECSID_NULL;
4434                 return 0;
4435         }
4436
4437         err = security_sid_mls_copy(sksec->sid, peersid, &newsid);
4438         if (err)
4439                 return err;
4440
4441         req->secid = newsid;
4442         req->peer_secid = peersid;
4443         return 0;
4444 }
4445
4446 static void selinux_inet_csk_clone(struct sock *newsk,
4447                                    const struct request_sock *req)
4448 {
4449         struct sk_security_struct *newsksec = newsk->sk_security;
4450
4451         newsksec->sid = req->secid;
4452         newsksec->peer_sid = req->peer_secid;
4453         /* NOTE: Ideally, we should also get the isec->sid for the
4454            new socket in sync, but we don't have the isec available yet.
4455            So we will wait until sock_graft to do it, by which
4456            time it will have been created and available. */
4457
4458         /* We don't need to take any sort of lock here as we are the only
4459          * thread with access to newsksec */
4460         selinux_netlbl_sk_security_reset(newsksec, req->rsk_ops->family);
4461 }
4462
4463 static void selinux_inet_conn_established(struct sock *sk, struct sk_buff *skb)
4464 {
4465         u16 family = sk->sk_family;
4466         struct sk_security_struct *sksec = sk->sk_security;
4467
4468         /* handle mapped IPv4 packets arriving via IPv6 sockets */
4469         if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
4470                 family = PF_INET;
4471
4472         selinux_skb_peerlbl_sid(skb, family, &sksec->peer_sid);
4473
4474         selinux_netlbl_inet_conn_established(sk, family);
4475 }
4476
4477 static void selinux_req_classify_flow(const struct request_sock *req,
4478                                       struct flowi *fl)
4479 {
4480         fl->secid = req->secid;
4481 }
4482
4483 static int selinux_nlmsg_perm(struct sock *sk, struct sk_buff *skb)
4484 {
4485         int err = 0;
4486         u32 perm;
4487         struct nlmsghdr *nlh;
4488         struct socket *sock = sk->sk_socket;
4489         struct inode_security_struct *isec = SOCK_INODE(sock)->i_security;
4490
4491         if (skb->len < NLMSG_SPACE(0)) {
4492                 err = -EINVAL;
4493                 goto out;
4494         }
4495         nlh = nlmsg_hdr(skb);
4496
4497         err = selinux_nlmsg_lookup(isec->sclass, nlh->nlmsg_type, &perm);
4498         if (err) {
4499                 if (err == -EINVAL) {
4500                         audit_log(current->audit_context, GFP_KERNEL, AUDIT_SELINUX_ERR,
4501                                   "SELinux:  unrecognized netlink message"
4502                                   " type=%hu for sclass=%hu\n",
4503                                   nlh->nlmsg_type, isec->sclass);
4504                         if (!selinux_enforcing || security_get_allow_unknown())
4505                                 err = 0;
4506                 }
4507
4508                 /* Ignore */
4509                 if (err == -ENOENT)
4510                         err = 0;
4511                 goto out;
4512         }
4513
4514         err = socket_has_perm(current, sock, perm);
4515 out:
4516         return err;
4517 }
4518
4519 #ifdef CONFIG_NETFILTER
4520
4521 static unsigned int selinux_ip_forward(struct sk_buff *skb, int ifindex,
4522                                        u16 family)
4523 {
4524         int err;
4525         char *addrp;
4526         u32 peer_sid;
4527         struct avc_audit_data ad;
4528         u8 secmark_active;
4529         u8 netlbl_active;
4530         u8 peerlbl_active;
4531
4532         if (!selinux_policycap_netpeer)
4533                 return NF_ACCEPT;
4534
4535         secmark_active = selinux_secmark_enabled();
4536         netlbl_active = netlbl_enabled();
4537         peerlbl_active = netlbl_active || selinux_xfrm_enabled();
4538         if (!secmark_active && !peerlbl_active)
4539                 return NF_ACCEPT;
4540
4541         if (selinux_skb_peerlbl_sid(skb, family, &peer_sid) != 0)
4542                 return NF_DROP;
4543
4544         AVC_AUDIT_DATA_INIT(&ad, NET);
4545         ad.u.net.netif = ifindex;
4546         ad.u.net.family = family;
4547         if (selinux_parse_skb(skb, &ad, &addrp, 1, NULL) != 0)
4548                 return NF_DROP;
4549
4550         if (peerlbl_active) {
4551                 err = selinux_inet_sys_rcv_skb(ifindex, addrp, family,
4552                                                peer_sid, &ad);
4553                 if (err) {
4554                         selinux_netlbl_err(skb, err, 1);
4555                         return NF_DROP;
4556                 }
4557         }
4558
4559         if (secmark_active)
4560                 if (avc_has_perm(peer_sid, skb->secmark,
4561                                  SECCLASS_PACKET, PACKET__FORWARD_IN, &ad))
4562                         return NF_DROP;
4563
4564         if (netlbl_active)
4565                 /* we do this in the FORWARD path and not the POST_ROUTING
4566                  * path because we want to make sure we apply the necessary
4567                  * labeling before IPsec is applied so we can leverage AH
4568                  * protection */
4569                 if (selinux_netlbl_skbuff_setsid(skb, family, peer_sid) != 0)
4570                         return NF_DROP;
4571
4572         return NF_ACCEPT;
4573 }
4574
4575 static unsigned int selinux_ipv4_forward(unsigned int hooknum,
4576                                          struct sk_buff *skb,
4577                                          const struct net_device *in,
4578                                          const struct net_device *out,
4579                                          int (*okfn)(struct sk_buff *))
4580 {
4581         return selinux_ip_forward(skb, in->ifindex, PF_INET);
4582 }
4583
4584 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
4585 static unsigned int selinux_ipv6_forward(unsigned int hooknum,
4586                                          struct sk_buff *skb,
4587                                          const struct net_device *in,
4588                                          const struct net_device *out,
4589                                          int (*okfn)(struct sk_buff *))
4590 {
4591         return selinux_ip_forward(skb, in->ifindex, PF_INET6);
4592 }
4593 #endif  /* IPV6 */
4594
4595 static unsigned int selinux_ip_output(struct sk_buff *skb,
4596                                       u16 family)
4597 {
4598         u32 sid;
4599
4600         if (!netlbl_enabled())
4601                 return NF_ACCEPT;
4602
4603         /* we do this in the LOCAL_OUT path and not the POST_ROUTING path
4604          * because we want to make sure we apply the necessary labeling
4605          * before IPsec is applied so we can leverage AH protection */
4606         if (skb->sk) {
4607                 struct sk_security_struct *sksec = skb->sk->sk_security;
4608                 sid = sksec->sid;
4609         } else
4610                 sid = SECINITSID_KERNEL;
4611         if (selinux_netlbl_skbuff_setsid(skb, family, sid) != 0)
4612                 return NF_DROP;
4613
4614         return NF_ACCEPT;
4615 }
4616
4617 static unsigned int selinux_ipv4_output(unsigned int hooknum,
4618                                         struct sk_buff *skb,
4619                                         const struct net_device *in,
4620                                         const struct net_device *out,
4621                                         int (*okfn)(struct sk_buff *))
4622 {
4623         return selinux_ip_output(skb, PF_INET);
4624 }
4625
4626 static int selinux_ip_postroute_iptables_compat(struct sock *sk,
4627                                                 int ifindex,
4628                                                 struct avc_audit_data *ad,
4629                                                 u16 family, char *addrp)
4630 {
4631         int err;
4632         struct sk_security_struct *sksec = sk->sk_security;
4633         u16 sk_class;
4634         u32 netif_perm, node_perm, send_perm;
4635         u32 port_sid, node_sid, if_sid, sk_sid;
4636
4637         sk_sid = sksec->sid;
4638         sk_class = sksec->sclass;
4639
4640         switch (sk_class) {
4641         case SECCLASS_UDP_SOCKET:
4642                 netif_perm = NETIF__UDP_SEND;
4643                 node_perm = NODE__UDP_SEND;
4644                 send_perm = UDP_SOCKET__SEND_MSG;
4645                 break;
4646         case SECCLASS_TCP_SOCKET:
4647                 netif_perm = NETIF__TCP_SEND;
4648                 node_perm = NODE__TCP_SEND;
4649                 send_perm = TCP_SOCKET__SEND_MSG;
4650                 break;
4651         case SECCLASS_DCCP_SOCKET:
4652                 netif_perm = NETIF__DCCP_SEND;
4653                 node_perm = NODE__DCCP_SEND;
4654                 send_perm = DCCP_SOCKET__SEND_MSG;
4655                 break;
4656         default:
4657                 netif_perm = NETIF__RAWIP_SEND;
4658                 node_perm = NODE__RAWIP_SEND;
4659                 send_perm = 0;
4660                 break;
4661         }
4662
4663         err = sel_netif_sid(ifindex, &if_sid);
4664         if (err)
4665                 return err;
4666         err = avc_has_perm(sk_sid, if_sid, SECCLASS_NETIF, netif_perm, ad);
4667                 return err;
4668
4669         err = sel_netnode_sid(addrp, family, &node_sid);
4670         if (err)
4671                 return err;
4672         err = avc_has_perm(sk_sid, node_sid, SECCLASS_NODE, node_perm, ad);
4673         if (err)
4674                 return err;
4675
4676         if (send_perm != 0)
4677                 return 0;
4678
4679         err = sel_netport_sid(sk->sk_protocol,
4680                               ntohs(ad->u.net.dport), &port_sid);
4681         if (unlikely(err)) {
4682                 printk(KERN_WARNING
4683                        "SELinux: failure in"
4684                        " selinux_ip_postroute_iptables_compat(),"
4685                        " network port label not found\n");
4686                 return err;
4687         }
4688         return avc_has_perm(sk_sid, port_sid, sk_class, send_perm, ad);
4689 }
4690
4691 static unsigned int selinux_ip_postroute_compat(struct sk_buff *skb,
4692                                                 int ifindex,
4693                                                 u16 family)
4694 {
4695         struct sock *sk = skb->sk;
4696         struct sk_security_struct *sksec;
4697         struct avc_audit_data ad;
4698         char *addrp;
4699         u8 proto;
4700
4701         if (sk == NULL)
4702                 return NF_ACCEPT;
4703         sksec = sk->sk_security;
4704
4705         AVC_AUDIT_DATA_INIT(&ad, NET);
4706         ad.u.net.netif = ifindex;
4707         ad.u.net.family = family;
4708         if (selinux_parse_skb(skb, &ad, &addrp, 0, &proto))
4709                 return NF_DROP;
4710
4711         if (selinux_compat_net) {
4712                 if (selinux_ip_postroute_iptables_compat(skb->sk, ifindex,
4713                                                          &ad, family, addrp))
4714                         return NF_DROP;
4715         } else if (selinux_secmark_enabled()) {
4716                 if (avc_has_perm(sksec->sid, skb->secmark,
4717                                  SECCLASS_PACKET, PACKET__SEND, &ad))
4718                         return NF_DROP;
4719         }
4720
4721         if (selinux_policycap_netpeer)
4722                 if (selinux_xfrm_postroute_last(sksec->sid, skb, &ad, proto))
4723                         return NF_DROP;
4724
4725         return NF_ACCEPT;
4726 }
4727
4728 static unsigned int selinux_ip_postroute(struct sk_buff *skb, int ifindex,
4729                                          u16 family)
4730 {
4731         u32 secmark_perm;
4732         u32 peer_sid;
4733         struct sock *sk;
4734         struct avc_audit_data ad;
4735         char *addrp;
4736         u8 secmark_active;
4737         u8 peerlbl_active;
4738
4739         /* If any sort of compatibility mode is enabled then handoff processing
4740          * to the selinux_ip_postroute_compat() function to deal with the
4741          * special handling.  We do this in an attempt to keep this function
4742          * as fast and as clean as possible. */
4743         if (selinux_compat_net || !selinux_policycap_netpeer)
4744                 return selinux_ip_postroute_compat(skb, ifindex, family);
4745 #ifdef CONFIG_XFRM
4746         /* If skb->dst->xfrm is non-NULL then the packet is undergoing an IPsec
4747          * packet transformation so allow the packet to pass without any checks
4748          * since we'll have another chance to perform access control checks
4749          * when the packet is on it's final way out.
4750          * NOTE: there appear to be some IPv6 multicast cases where skb->dst
4751          *       is NULL, in this case go ahead and apply access control. */
4752         if (skb->dst != NULL && skb->dst->xfrm != NULL)
4753                 return NF_ACCEPT;
4754 #endif
4755         secmark_active = selinux_secmark_enabled();
4756         peerlbl_active = netlbl_enabled() || selinux_xfrm_enabled();
4757         if (!secmark_active && !peerlbl_active)
4758                 return NF_ACCEPT;
4759
4760         /* if the packet is being forwarded then get the peer label from the
4761          * packet itself; otherwise check to see if it is from a local
4762          * application or the kernel, if from an application get the peer label
4763          * from the sending socket, otherwise use the kernel's sid */
4764         sk = skb->sk;
4765         if (sk == NULL) {
4766                 switch (family) {
4767                 case PF_INET:
4768                         if (IPCB(skb)->flags & IPSKB_FORWARDED)
4769                                 secmark_perm = PACKET__FORWARD_OUT;
4770                         else
4771                                 secmark_perm = PACKET__SEND;
4772                         break;
4773                 case PF_INET6:
4774                         if (IP6CB(skb)->flags & IP6SKB_FORWARDED)
4775                                 secmark_perm = PACKET__FORWARD_OUT;
4776                         else
4777                                 secmark_perm = PACKET__SEND;
4778                         break;
4779                 default:
4780                         return NF_DROP;
4781                 }
4782                 if (secmark_perm == PACKET__FORWARD_OUT) {
4783                         if (selinux_skb_peerlbl_sid(skb, family, &peer_sid))
4784                                 return NF_DROP;
4785                 } else
4786                         peer_sid = SECINITSID_KERNEL;
4787         } else {
4788                 struct sk_security_struct *sksec = sk->sk_security;
4789                 peer_sid = sksec->sid;
4790                 secmark_perm = PACKET__SEND;
4791         }
4792
4793         AVC_AUDIT_DATA_INIT(&ad, NET);
4794         ad.u.net.netif = ifindex;
4795         ad.u.net.family = family;
4796         if (selinux_parse_skb(skb, &ad, &addrp, 0, NULL))
4797                 return NF_DROP;
4798
4799         if (secmark_active)
4800                 if (avc_has_perm(peer_sid, skb->secmark,
4801                                  SECCLASS_PACKET, secmark_perm, &ad))
4802                         return NF_DROP;
4803
4804         if (peerlbl_active) {
4805                 u32 if_sid;
4806                 u32 node_sid;
4807
4808                 if (sel_netif_sid(ifindex, &if_sid))
4809                         return NF_DROP;
4810                 if (avc_has_perm(peer_sid, if_sid,
4811                                  SECCLASS_NETIF, NETIF__EGRESS, &ad))
4812                         return NF_DROP;
4813
4814                 if (sel_netnode_sid(addrp, family, &node_sid))
4815                         return NF_DROP;
4816                 if (avc_has_perm(peer_sid, node_sid,
4817                                  SECCLASS_NODE, NODE__SENDTO, &ad))
4818                         return NF_DROP;
4819         }
4820
4821         return NF_ACCEPT;
4822 }
4823
4824 static unsigned int selinux_ipv4_postroute(unsigned int hooknum,
4825                                            struct sk_buff *skb,
4826                                            const struct net_device *in,
4827                                            const struct net_device *out,
4828                                            int (*okfn)(struct sk_buff *))
4829 {
4830         return selinux_ip_postroute(skb, out->ifindex, PF_INET);
4831 }
4832
4833 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
4834 static unsigned int selinux_ipv6_postroute(unsigned int hooknum,
4835                                            struct sk_buff *skb,
4836                                            const struct net_device *in,
4837                                            const struct net_device *out,
4838                                            int (*okfn)(struct sk_buff *))
4839 {
4840         return selinux_ip_postroute(skb, out->ifindex, PF_INET6);
4841 }
4842 #endif  /* IPV6 */
4843
4844 #endif  /* CONFIG_NETFILTER */
4845
4846 static int selinux_netlink_send(struct sock *sk, struct sk_buff *skb)
4847 {
4848         int err;
4849
4850         err = secondary_ops->netlink_send(sk, skb);
4851         if (err)
4852                 return err;
4853
4854         if (policydb_loaded_version >= POLICYDB_VERSION_NLCLASS)
4855                 err = selinux_nlmsg_perm(sk, skb);
4856
4857         return err;
4858 }
4859
4860 static int selinux_netlink_recv(struct sk_buff *skb, int capability)
4861 {
4862         int err;
4863         struct avc_audit_data ad;
4864
4865         err = secondary_ops->netlink_recv(skb, capability);
4866         if (err)
4867                 return err;
4868
4869         AVC_AUDIT_DATA_INIT(&ad, CAP);
4870         ad.u.cap = capability;
4871
4872         return avc_has_perm(NETLINK_CB(skb).sid, NETLINK_CB(skb).sid,
4873                             SECCLASS_CAPABILITY, CAP_TO_MASK(capability), &ad);
4874 }
4875
4876 static int ipc_alloc_security(struct task_struct *task,
4877                               struct kern_ipc_perm *perm,
4878                               u16 sclass)
4879 {
4880         struct ipc_security_struct *isec;
4881         u32 sid;
4882
4883         isec = kzalloc(sizeof(struct ipc_security_struct), GFP_KERNEL);
4884         if (!isec)
4885                 return -ENOMEM;
4886
4887         sid = task_sid(task);
4888         isec->sclass = sclass;
4889         isec->sid = sid;
4890         perm->security = isec;
4891
4892         return 0;
4893 }
4894
4895 static void ipc_free_security(struct kern_ipc_perm *perm)
4896 {
4897         struct ipc_security_struct *isec = perm->security;
4898         perm->security = NULL;
4899         kfree(isec);
4900 }
4901
4902 static int msg_msg_alloc_security(struct msg_msg *msg)
4903 {
4904         struct msg_security_struct *msec;
4905
4906         msec = kzalloc(sizeof(struct msg_security_struct), GFP_KERNEL);
4907         if (!msec)
4908                 return -ENOMEM;
4909
4910         msec->sid = SECINITSID_UNLABELED;
4911         msg->security = msec;
4912
4913         return 0;
4914 }
4915
4916 static void msg_msg_free_security(struct msg_msg *msg)
4917 {
4918         struct msg_security_struct *msec = msg->security;
4919
4920         msg->security = NULL;
4921         kfree(msec);
4922 }
4923
4924 static int ipc_has_perm(struct kern_ipc_perm *ipc_perms,
4925                         u32 perms)
4926 {
4927         struct ipc_security_struct *isec;
4928         struct avc_audit_data ad;
4929         u32 sid = current_sid();
4930
4931         isec = ipc_perms->security;
4932
4933         AVC_AUDIT_DATA_INIT(&ad, IPC);
4934         ad.u.ipc_id = ipc_perms->key;
4935
4936         return avc_has_perm(sid, isec->sid, isec->sclass, perms, &ad);
4937 }
4938
4939 static int selinux_msg_msg_alloc_security(struct msg_msg *msg)
4940 {
4941         return msg_msg_alloc_security(msg);
4942 }
4943
4944 static void selinux_msg_msg_free_security(struct msg_msg *msg)
4945 {
4946         msg_msg_free_security(msg);
4947 }
4948
4949 /* message queue security operations */
4950 static int selinux_msg_queue_alloc_security(struct msg_queue *msq)
4951 {
4952         struct ipc_security_struct *isec;
4953         struct avc_audit_data ad;
4954         u32 sid = current_sid();
4955         int rc;
4956
4957         rc = ipc_alloc_security(current, &msq->q_perm, SECCLASS_MSGQ);
4958         if (rc)
4959                 return rc;
4960
4961         isec = msq->q_perm.security;
4962
4963         AVC_AUDIT_DATA_INIT(&ad, IPC);
4964         ad.u.ipc_id = msq->q_perm.key;
4965
4966         rc = avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
4967                           MSGQ__CREATE, &ad);
4968         if (rc) {
4969                 ipc_free_security(&msq->q_perm);
4970                 return rc;
4971         }
4972         return 0;
4973 }
4974
4975 static void selinux_msg_queue_free_security(struct msg_queue *msq)
4976 {
4977         ipc_free_security(&msq->q_perm);
4978 }
4979
4980 static int selinux_msg_queue_associate(struct msg_queue *msq, int msqflg)
4981 {
4982         struct ipc_security_struct *isec;
4983         struct avc_audit_data ad;
4984         u32 sid = current_sid();
4985
4986         isec = msq->q_perm.security;
4987
4988         AVC_AUDIT_DATA_INIT(&ad, IPC);
4989         ad.u.ipc_id = msq->q_perm.key;
4990
4991         return avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
4992                             MSGQ__ASSOCIATE, &ad);
4993 }
4994
4995 static int selinux_msg_queue_msgctl(struct msg_queue *msq, int cmd)
4996 {
4997         int err;
4998         int perms;
4999
5000         switch (cmd) {
5001         case IPC_INFO:
5002         case MSG_INFO:
5003                 /* No specific object, just general system-wide information. */
5004                 return task_has_system(current, SYSTEM__IPC_INFO);
5005         case IPC_STAT:
5006         case MSG_STAT:
5007                 perms = MSGQ__GETATTR | MSGQ__ASSOCIATE;
5008                 break;
5009         case IPC_SET:
5010                 perms = MSGQ__SETATTR;
5011                 break;
5012         case IPC_RMID:
5013                 perms = MSGQ__DESTROY;
5014                 break;
5015         default:
5016                 return 0;
5017         }
5018
5019         err = ipc_has_perm(&msq->q_perm, perms);
5020         return err;
5021 }
5022
5023 static int selinux_msg_queue_msgsnd(struct msg_queue *msq, struct msg_msg *msg, int msqflg)
5024 {
5025         struct ipc_security_struct *isec;
5026         struct msg_security_struct *msec;
5027         struct avc_audit_data ad;
5028         u32 sid = current_sid();
5029         int rc;
5030
5031         isec = msq->q_perm.security;
5032         msec = msg->security;
5033
5034         /*
5035          * First time through, need to assign label to the message
5036          */
5037         if (msec->sid == SECINITSID_UNLABELED) {
5038                 /*
5039                  * Compute new sid based on current process and
5040                  * message queue this message will be stored in
5041                  */
5042                 rc = security_transition_sid(sid, isec->sid, SECCLASS_MSG,
5043                                              &msec->sid);
5044                 if (rc)
5045                         return rc;
5046         }
5047
5048         AVC_AUDIT_DATA_INIT(&ad, IPC);
5049         ad.u.ipc_id = msq->q_perm.key;
5050
5051         /* Can this process write to the queue? */
5052         rc = avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
5053                           MSGQ__WRITE, &ad);
5054         if (!rc)
5055                 /* Can this process send the message */
5056                 rc = avc_has_perm(sid, msec->sid, SECCLASS_MSG,
5057                                   MSG__SEND, &ad);
5058         if (!rc)
5059                 /* Can the message be put in the queue? */
5060                 rc = avc_has_perm(msec->sid, isec->sid, SECCLASS_MSGQ,
5061                                   MSGQ__ENQUEUE, &ad);
5062
5063         return rc;
5064 }
5065
5066 static int selinux_msg_queue_msgrcv(struct msg_queue *msq, struct msg_msg *msg,
5067                                     struct task_struct *target,
5068                                     long type, int mode)
5069 {
5070         struct ipc_security_struct *isec;
5071         struct msg_security_struct *msec;
5072         struct avc_audit_data ad;
5073         u32 sid = task_sid(target);
5074         int rc;
5075
5076         isec = msq->q_perm.security;
5077         msec = msg->security;
5078
5079         AVC_AUDIT_DATA_INIT(&ad, IPC);
5080         ad.u.ipc_id = msq->q_perm.key;
5081
5082         rc = avc_has_perm(sid, isec->sid,
5083                           SECCLASS_MSGQ, MSGQ__READ, &ad);
5084         if (!rc)
5085                 rc = avc_has_perm(sid, msec->sid,
5086                                   SECCLASS_MSG, MSG__RECEIVE, &ad);
5087         return rc;
5088 }
5089
5090 /* Shared Memory security operations */
5091 static int selinux_shm_alloc_security(struct shmid_kernel *shp)
5092 {
5093         struct ipc_security_struct *isec;
5094         struct avc_audit_data ad;
5095         u32 sid = current_sid();
5096         int rc;
5097
5098         rc = ipc_alloc_security(current, &shp->shm_perm, SECCLASS_SHM);
5099         if (rc)
5100                 return rc;
5101
5102         isec = shp->shm_perm.security;
5103
5104         AVC_AUDIT_DATA_INIT(&ad, IPC);
5105         ad.u.ipc_id = shp->shm_perm.key;
5106
5107         rc = avc_has_perm(sid, isec->sid, SECCLASS_SHM,
5108                           SHM__CREATE, &ad);
5109         if (rc) {
5110                 ipc_free_security(&shp->shm_perm);
5111                 return rc;
5112         }
5113         return 0;
5114 }
5115
5116 static void selinux_shm_free_security(struct shmid_kernel *shp)
5117 {
5118         ipc_free_security(&shp->shm_perm);
5119 }
5120
5121 static int selinux_shm_associate(struct shmid_kernel *shp, int shmflg)
5122 {
5123         struct ipc_security_struct *isec;
5124         struct avc_audit_data ad;
5125         u32 sid = current_sid();
5126
5127         isec = shp->shm_perm.security;
5128
5129         AVC_AUDIT_DATA_INIT(&ad, IPC);
5130         ad.u.ipc_id = shp->shm_perm.key;
5131
5132         return avc_has_perm(sid, isec->sid, SECCLASS_SHM,
5133                             SHM__ASSOCIATE, &ad);
5134 }
5135
5136 /* Note, at this point, shp is locked down */
5137 static int selinux_shm_shmctl(struct shmid_kernel *shp, int cmd)
5138 {
5139         int perms;
5140         int err;
5141
5142         switch (cmd) {
5143         case IPC_INFO:
5144         case SHM_INFO:
5145                 /* No specific object, just general system-wide information. */
5146                 return task_has_system(current, SYSTEM__IPC_INFO);
5147         case IPC_STAT:
5148         case SHM_STAT:
5149                 perms = SHM__GETATTR | SHM__ASSOCIATE;
5150                 break;
5151         case IPC_SET:
5152                 perms = SHM__SETATTR;
5153                 break;
5154         case SHM_LOCK:
5155         case SHM_UNLOCK:
5156                 perms = SHM__LOCK;
5157                 break;
5158         case IPC_RMID:
5159                 perms = SHM__DESTROY;
5160                 break;
5161         default:
5162                 return 0;
5163         }
5164
5165         err = ipc_has_perm(&shp->shm_perm, perms);
5166         return err;
5167 }
5168
5169 static int selinux_shm_shmat(struct shmid_kernel *shp,
5170                              char __user *shmaddr, int shmflg)
5171 {
5172         u32 perms;
5173         int rc;
5174
5175         rc = secondary_ops->shm_shmat(shp, shmaddr, shmflg);
5176         if (rc)
5177                 return rc;
5178
5179         if (shmflg & SHM_RDONLY)
5180                 perms = SHM__READ;
5181         else
5182                 perms = SHM__READ | SHM__WRITE;
5183
5184         return ipc_has_perm(&shp->shm_perm, perms);
5185 }
5186
5187 /* Semaphore security operations */
5188 static int selinux_sem_alloc_security(struct sem_array *sma)
5189 {
5190         struct ipc_security_struct *isec;
5191         struct avc_audit_data ad;
5192         u32 sid = current_sid();
5193         int rc;
5194
5195         rc = ipc_alloc_security(current, &sma->sem_perm, SECCLASS_SEM);
5196         if (rc)
5197                 return rc;
5198
5199         isec = sma->sem_perm.security;
5200
5201         AVC_AUDIT_DATA_INIT(&ad, IPC);
5202         ad.u.ipc_id = sma->sem_perm.key;
5203
5204         rc = avc_has_perm(sid, isec->sid, SECCLASS_SEM,
5205                           SEM__CREATE, &ad);
5206         if (rc) {
5207                 ipc_free_security(&sma->sem_perm);
5208                 return rc;
5209         }
5210         return 0;
5211 }
5212
5213 static void selinux_sem_free_security(struct sem_array *sma)
5214 {
5215         ipc_free_security(&sma->sem_perm);
5216 }
5217
5218 static int selinux_sem_associate(struct sem_array *sma, int semflg)
5219 {
5220         struct ipc_security_struct *isec;
5221         struct avc_audit_data ad;
5222         u32 sid = current_sid();
5223
5224         isec = sma->sem_perm.security;
5225
5226         AVC_AUDIT_DATA_INIT(&ad, IPC);
5227         ad.u.ipc_id = sma->sem_perm.key;
5228
5229         return avc_has_perm(sid, isec->sid, SECCLASS_SEM,
5230                             SEM__ASSOCIATE, &ad);
5231 }
5232
5233 /* Note, at this point, sma is locked down */
5234 static int selinux_sem_semctl(struct sem_array *sma, int cmd)
5235 {
5236         int err;
5237         u32 perms;
5238
5239         switch (cmd) {
5240         case IPC_INFO:
5241         case SEM_INFO:
5242                 /* No specific object, just general system-wide information. */
5243                 return task_has_system(current, SYSTEM__IPC_INFO);
5244         case GETPID:
5245         case GETNCNT:
5246         case GETZCNT:
5247                 perms = SEM__GETATTR;
5248                 break;
5249         case GETVAL:
5250         case GETALL:
5251                 perms = SEM__READ;
5252                 break;
5253         case SETVAL:
5254         case SETALL:
5255                 perms = SEM__WRITE;
5256                 break;
5257         case IPC_RMID:
5258                 perms = SEM__DESTROY;
5259                 break;
5260         case IPC_SET:
5261                 perms = SEM__SETATTR;
5262                 break;
5263         case IPC_STAT:
5264         case SEM_STAT:
5265                 perms = SEM__GETATTR | SEM__ASSOCIATE;
5266                 break;
5267         default:
5268                 return 0;
5269         }
5270
5271         err = ipc_has_perm(&sma->sem_perm, perms);
5272         return err;
5273 }
5274
5275 static int selinux_sem_semop(struct sem_array *sma,
5276                              struct sembuf *sops, unsigned nsops, int alter)
5277 {
5278         u32 perms;
5279
5280         if (alter)
5281                 perms = SEM__READ | SEM__WRITE;
5282         else
5283                 perms = SEM__READ;
5284
5285         return ipc_has_perm(&sma->sem_perm, perms);
5286 }
5287
5288 static int selinux_ipc_permission(struct kern_ipc_perm *ipcp, short flag)
5289 {
5290         u32 av = 0;
5291
5292         av = 0;
5293         if (flag & S_IRUGO)
5294                 av |= IPC__UNIX_READ;
5295         if (flag & S_IWUGO)
5296                 av |= IPC__UNIX_WRITE;
5297
5298         if (av == 0)
5299                 return 0;
5300
5301         return ipc_has_perm(ipcp, av);
5302 }
5303
5304 static void selinux_ipc_getsecid(struct kern_ipc_perm *ipcp, u32 *secid)
5305 {
5306         struct ipc_security_struct *isec = ipcp->security;
5307         *secid = isec->sid;
5308 }
5309
5310 static void selinux_d_instantiate(struct dentry *dentry, struct inode *inode)
5311 {
5312         if (inode)
5313                 inode_doinit_with_dentry(inode, dentry);
5314 }
5315
5316 static int selinux_getprocattr(struct task_struct *p,
5317                                char *name, char **value)
5318 {
5319         const struct task_security_struct *__tsec;
5320         u32 sid;
5321         int error;
5322         unsigned len;
5323
5324         if (current != p) {
5325                 error = current_has_perm(p, PROCESS__GETATTR);
5326                 if (error)
5327                         return error;
5328         }
5329
5330         rcu_read_lock();
5331         __tsec = __task_cred(p)->security;
5332
5333         if (!strcmp(name, "current"))
5334                 sid = __tsec->sid;
5335         else if (!strcmp(name, "prev"))
5336                 sid = __tsec->osid;
5337         else if (!strcmp(name, "exec"))
5338                 sid = __tsec->exec_sid;
5339         else if (!strcmp(name, "fscreate"))
5340                 sid = __tsec->create_sid;
5341         else if (!strcmp(name, "keycreate"))
5342                 sid = __tsec->keycreate_sid;
5343         else if (!strcmp(name, "sockcreate"))
5344                 sid = __tsec->sockcreate_sid;
5345         else
5346                 goto invalid;
5347         rcu_read_unlock();
5348
5349         if (!sid)
5350                 return 0;
5351
5352         error = security_sid_to_context(sid, value, &len);
5353         if (error)
5354                 return error;
5355         return len;
5356
5357 invalid:
5358         rcu_read_unlock();
5359         return -EINVAL;
5360 }
5361
5362 static int selinux_setprocattr(struct task_struct *p,
5363                                char *name, void *value, size_t size)
5364 {
5365         struct task_security_struct *tsec;
5366         struct task_struct *tracer;
5367         struct cred *new;
5368         u32 sid = 0, ptsid;
5369         int error;
5370         char *str = value;
5371
5372         if (current != p) {
5373                 /* SELinux only allows a process to change its own
5374                    security attributes. */
5375                 return -EACCES;
5376         }
5377
5378         /*
5379          * Basic control over ability to set these attributes at all.
5380          * current == p, but we'll pass them separately in case the
5381          * above restriction is ever removed.
5382          */
5383         if (!strcmp(name, "exec"))
5384                 error = current_has_perm(p, PROCESS__SETEXEC);
5385         else if (!strcmp(name, "fscreate"))
5386                 error = current_has_perm(p, PROCESS__SETFSCREATE);
5387         else if (!strcmp(name, "keycreate"))
5388                 error = current_has_perm(p, PROCESS__SETKEYCREATE);
5389         else if (!strcmp(name, "sockcreate"))
5390                 error = current_has_perm(p, PROCESS__SETSOCKCREATE);
5391         else if (!strcmp(name, "current"))
5392                 error = current_has_perm(p, PROCESS__SETCURRENT);
5393         else
5394                 error = -EINVAL;
5395         if (error)
5396                 return error;
5397
5398         /* Obtain a SID for the context, if one was specified. */
5399         if (size && str[1] && str[1] != '\n') {
5400                 if (str[size-1] == '\n') {
5401                         str[size-1] = 0;
5402                         size--;
5403                 }
5404                 error = security_context_to_sid(value, size, &sid);
5405                 if (error == -EINVAL && !strcmp(name, "fscreate")) {
5406                         if (!capable(CAP_MAC_ADMIN))
5407                                 return error;
5408                         error = security_context_to_sid_force(value, size,
5409                                                               &sid);
5410                 }
5411                 if (error)
5412                         return error;
5413         }
5414
5415         new = prepare_creds();
5416         if (!new)
5417                 return -ENOMEM;
5418
5419         /* Permission checking based on the specified context is
5420            performed during the actual operation (execve,
5421            open/mkdir/...), when we know the full context of the
5422            operation.  See selinux_bprm_set_creds for the execve
5423            checks and may_create for the file creation checks. The
5424            operation will then fail if the context is not permitted. */
5425         tsec = new->security;
5426         if (!strcmp(name, "exec")) {
5427                 tsec->exec_sid = sid;
5428         } else if (!strcmp(name, "fscreate")) {
5429                 tsec->create_sid = sid;
5430         } else if (!strcmp(name, "keycreate")) {
5431                 error = may_create_key(sid, p);
5432                 if (error)
5433                         goto abort_change;
5434                 tsec->keycreate_sid = sid;
5435         } else if (!strcmp(name, "sockcreate")) {
5436                 tsec->sockcreate_sid = sid;
5437         } else if (!strcmp(name, "current")) {
5438                 error = -EINVAL;
5439                 if (sid == 0)
5440                         goto abort_change;
5441
5442                 /* Only allow single threaded processes to change context */
5443                 error = -EPERM;
5444                 if (!is_single_threaded(p)) {
5445                         error = security_bounded_transition(tsec->sid, sid);
5446                         if (error)
5447                                 goto abort_change;
5448                 }
5449
5450                 /* Check permissions for the transition. */
5451                 error = avc_has_perm(tsec->sid, sid, SECCLASS_PROCESS,
5452                                      PROCESS__DYNTRANSITION, NULL);
5453                 if (error)
5454                         goto abort_change;
5455
5456                 /* Check for ptracing, and update the task SID if ok.
5457                    Otherwise, leave SID unchanged and fail. */
5458                 ptsid = 0;
5459                 task_lock(p);
5460                 tracer = tracehook_tracer_task(p);
5461                 if (tracer)
5462                         ptsid = task_sid(tracer);
5463                 task_unlock(p);
5464
5465                 if (tracer) {
5466                         error = avc_has_perm(ptsid, sid, SECCLASS_PROCESS,
5467                                              PROCESS__PTRACE, NULL);
5468                         if (error)
5469                                 goto abort_change;
5470                 }
5471
5472                 tsec->sid = sid;
5473         } else {
5474                 error = -EINVAL;
5475                 goto abort_change;
5476         }
5477
5478         commit_creds(new);
5479         return size;
5480
5481 abort_change:
5482         abort_creds(new);
5483         return error;
5484 }
5485
5486 static int selinux_secid_to_secctx(u32 secid, char **secdata, u32 *seclen)
5487 {
5488         return security_sid_to_context(secid, secdata, seclen);
5489 }
5490
5491 static int selinux_secctx_to_secid(const char *secdata, u32 seclen, u32 *secid)
5492 {
5493         return security_context_to_sid(secdata, seclen, secid);
5494 }
5495
5496 static void selinux_release_secctx(char *secdata, u32 seclen)
5497 {
5498         kfree(secdata);
5499 }
5500
5501 #ifdef CONFIG_KEYS
5502
5503 static int selinux_key_alloc(struct key *k, const struct cred *cred,
5504                              unsigned long flags)
5505 {
5506         const struct task_security_struct *tsec;
5507         struct key_security_struct *ksec;
5508
5509         ksec = kzalloc(sizeof(struct key_security_struct), GFP_KERNEL);
5510         if (!ksec)
5511                 return -ENOMEM;
5512
5513         tsec = cred->security;
5514         if (tsec->keycreate_sid)
5515                 ksec->sid = tsec->keycreate_sid;
5516         else
5517                 ksec->sid = tsec->sid;
5518
5519         k->security = ksec;
5520         return 0;
5521 }
5522
5523 static void selinux_key_free(struct key *k)
5524 {
5525         struct key_security_struct *ksec = k->security;
5526
5527         k->security = NULL;
5528         kfree(ksec);
5529 }
5530
5531 static int selinux_key_permission(key_ref_t key_ref,
5532                                   const struct cred *cred,
5533                                   key_perm_t perm)
5534 {
5535         struct key *key;
5536         struct key_security_struct *ksec;
5537         u32 sid;
5538
5539         /* if no specific permissions are requested, we skip the
5540            permission check. No serious, additional covert channels
5541            appear to be created. */
5542         if (perm == 0)
5543                 return 0;
5544
5545         sid = cred_sid(cred);
5546
5547         key = key_ref_to_ptr(key_ref);
5548         ksec = key->security;
5549
5550         return avc_has_perm(sid, ksec->sid, SECCLASS_KEY, perm, NULL);
5551 }
5552
5553 static int selinux_key_getsecurity(struct key *key, char **_buffer)
5554 {
5555         struct key_security_struct *ksec = key->security;
5556         char *context = NULL;
5557         unsigned len;
5558         int rc;
5559
5560         rc = security_sid_to_context(ksec->sid, &context, &len);
5561         if (!rc)
5562                 rc = len;
5563         *_buffer = context;
5564         return rc;
5565 }
5566
5567 #endif
5568
5569 static struct security_operations selinux_ops = {
5570         .name =                         "selinux",
5571
5572         .ptrace_may_access =            selinux_ptrace_may_access,
5573         .ptrace_traceme =               selinux_ptrace_traceme,
5574         .capget =                       selinux_capget,
5575         .capset =                       selinux_capset,
5576         .sysctl =                       selinux_sysctl,
5577         .capable =                      selinux_capable,
5578         .quotactl =                     selinux_quotactl,
5579         .quota_on =                     selinux_quota_on,
5580         .syslog =                       selinux_syslog,
5581         .vm_enough_memory =             selinux_vm_enough_memory,
5582
5583         .netlink_send =                 selinux_netlink_send,
5584         .netlink_recv =                 selinux_netlink_recv,
5585
5586         .bprm_set_creds =               selinux_bprm_set_creds,
5587         .bprm_committing_creds =        selinux_bprm_committing_creds,
5588         .bprm_committed_creds =         selinux_bprm_committed_creds,
5589         .bprm_secureexec =              selinux_bprm_secureexec,
5590
5591         .sb_alloc_security =            selinux_sb_alloc_security,
5592         .sb_free_security =             selinux_sb_free_security,
5593         .sb_copy_data =                 selinux_sb_copy_data,
5594         .sb_kern_mount =                selinux_sb_kern_mount,
5595         .sb_show_options =              selinux_sb_show_options,
5596         .sb_statfs =                    selinux_sb_statfs,
5597         .sb_mount =                     selinux_mount,
5598         .sb_umount =                    selinux_umount,
5599         .sb_set_mnt_opts =              selinux_set_mnt_opts,
5600         .sb_clone_mnt_opts =            selinux_sb_clone_mnt_opts,
5601         .sb_parse_opts_str =            selinux_parse_opts_str,
5602
5603
5604         .inode_alloc_security =         selinux_inode_alloc_security,
5605         .inode_free_security =          selinux_inode_free_security,
5606         .inode_init_security =          selinux_inode_init_security,
5607         .inode_create =                 selinux_inode_create,
5608         .inode_link =                   selinux_inode_link,
5609         .inode_unlink =                 selinux_inode_unlink,
5610         .inode_symlink =                selinux_inode_symlink,
5611         .inode_mkdir =                  selinux_inode_mkdir,
5612         .inode_rmdir =                  selinux_inode_rmdir,
5613         .inode_mknod =                  selinux_inode_mknod,
5614         .inode_rename =                 selinux_inode_rename,
5615         .inode_readlink =               selinux_inode_readlink,
5616         .inode_follow_link =            selinux_inode_follow_link,
5617         .inode_permission =             selinux_inode_permission,
5618         .inode_setattr =                selinux_inode_setattr,
5619         .inode_getattr =                selinux_inode_getattr,
5620         .inode_setxattr =               selinux_inode_setxattr,
5621         .inode_post_setxattr =          selinux_inode_post_setxattr,
5622         .inode_getxattr =               selinux_inode_getxattr,
5623         .inode_listxattr =              selinux_inode_listxattr,
5624         .inode_removexattr =            selinux_inode_removexattr,
5625         .inode_getsecurity =            selinux_inode_getsecurity,
5626         .inode_setsecurity =            selinux_inode_setsecurity,
5627         .inode_listsecurity =           selinux_inode_listsecurity,
5628         .inode_need_killpriv =          selinux_inode_need_killpriv,
5629         .inode_killpriv =               selinux_inode_killpriv,
5630         .inode_getsecid =               selinux_inode_getsecid,
5631
5632         .file_permission =              selinux_file_permission,
5633         .file_alloc_security =          selinux_file_alloc_security,
5634         .file_free_security =           selinux_file_free_security,
5635         .file_ioctl =                   selinux_file_ioctl,
5636         .file_mmap =                    selinux_file_mmap,
5637         .file_mprotect =                selinux_file_mprotect,
5638         .file_lock =                    selinux_file_lock,
5639         .file_fcntl =                   selinux_file_fcntl,
5640         .file_set_fowner =              selinux_file_set_fowner,
5641         .file_send_sigiotask =          selinux_file_send_sigiotask,
5642         .file_receive =                 selinux_file_receive,
5643
5644         .dentry_open =                  selinux_dentry_open,
5645
5646         .task_create =                  selinux_task_create,
5647         .cred_free =                    selinux_cred_free,
5648         .cred_prepare =                 selinux_cred_prepare,
5649         .cred_commit =                  selinux_cred_commit,
5650         .kernel_act_as =                selinux_kernel_act_as,
5651         .kernel_create_files_as =       selinux_kernel_create_files_as,
5652         .task_setuid =                  selinux_task_setuid,
5653         .task_fix_setuid =              selinux_task_fix_setuid,
5654         .task_setgid =                  selinux_task_setgid,
5655         .task_setpgid =                 selinux_task_setpgid,
5656         .task_getpgid =                 selinux_task_getpgid,
5657         .task_getsid =                  selinux_task_getsid,
5658         .task_getsecid =                selinux_task_getsecid,
5659         .task_setgroups =               selinux_task_setgroups,
5660         .task_setnice =                 selinux_task_setnice,
5661         .task_setioprio =               selinux_task_setioprio,
5662         .task_getioprio =               selinux_task_getioprio,
5663         .task_setrlimit =               selinux_task_setrlimit,
5664         .task_setscheduler =            selinux_task_setscheduler,
5665         .task_getscheduler =            selinux_task_getscheduler,
5666         .task_movememory =              selinux_task_movememory,
5667         .task_kill =                    selinux_task_kill,
5668         .task_wait =                    selinux_task_wait,
5669         .task_prctl =                   selinux_task_prctl,
5670         .task_to_inode =                selinux_task_to_inode,
5671
5672         .ipc_permission =               selinux_ipc_permission,
5673         .ipc_getsecid =                 selinux_ipc_getsecid,
5674
5675         .msg_msg_alloc_security =       selinux_msg_msg_alloc_security,
5676         .msg_msg_free_security =        selinux_msg_msg_free_security,
5677
5678         .msg_queue_alloc_security =     selinux_msg_queue_alloc_security,
5679         .msg_queue_free_security =      selinux_msg_queue_free_security,
5680         .msg_queue_associate =          selinux_msg_queue_associate,
5681         .msg_queue_msgctl =             selinux_msg_queue_msgctl,
5682         .msg_queue_msgsnd =             selinux_msg_queue_msgsnd,
5683         .msg_queue_msgrcv =             selinux_msg_queue_msgrcv,
5684
5685         .shm_alloc_security =           selinux_shm_alloc_security,
5686         .shm_free_security =            selinux_shm_free_security,
5687         .shm_associate =                selinux_shm_associate,
5688         .shm_shmctl =                   selinux_shm_shmctl,
5689         .shm_shmat =                    selinux_shm_shmat,
5690
5691         .sem_alloc_security =           selinux_sem_alloc_security,
5692         .sem_free_security =            selinux_sem_free_security,
5693         .sem_associate =                selinux_sem_associate,
5694         .sem_semctl =                   selinux_sem_semctl,
5695         .sem_semop =                    selinux_sem_semop,
5696
5697         .d_instantiate =                selinux_d_instantiate,
5698
5699         .getprocattr =                  selinux_getprocattr,
5700         .setprocattr =                  selinux_setprocattr,
5701
5702         .secid_to_secctx =              selinux_secid_to_secctx,
5703         .secctx_to_secid =              selinux_secctx_to_secid,
5704         .release_secctx =               selinux_release_secctx,
5705
5706         .unix_stream_connect =          selinux_socket_unix_stream_connect,
5707         .unix_may_send =                selinux_socket_unix_may_send,
5708
5709         .socket_create =                selinux_socket_create,
5710         .socket_post_create =           selinux_socket_post_create,
5711         .socket_bind =                  selinux_socket_bind,
5712         .socket_connect =               selinux_socket_connect,
5713         .socket_listen =                selinux_socket_listen,
5714         .socket_accept =                selinux_socket_accept,
5715         .socket_sendmsg =               selinux_socket_sendmsg,
5716         .socket_recvmsg =               selinux_socket_recvmsg,
5717         .socket_getsockname =           selinux_socket_getsockname,
5718         .socket_getpeername =           selinux_socket_getpeername,
5719         .socket_getsockopt =            selinux_socket_getsockopt,
5720         .socket_setsockopt =            selinux_socket_setsockopt,
5721         .socket_shutdown =              selinux_socket_shutdown,
5722         .socket_sock_rcv_skb =          selinux_socket_sock_rcv_skb,
5723         .socket_getpeersec_stream =     selinux_socket_getpeersec_stream,
5724         .socket_getpeersec_dgram =      selinux_socket_getpeersec_dgram,
5725         .sk_alloc_security =            selinux_sk_alloc_security,
5726         .sk_free_security =             selinux_sk_free_security,
5727         .sk_clone_security =            selinux_sk_clone_security,
5728         .sk_getsecid =                  selinux_sk_getsecid,
5729         .sock_graft =                   selinux_sock_graft,
5730         .inet_conn_request =            selinux_inet_conn_request,
5731         .inet_csk_clone =               selinux_inet_csk_clone,
5732         .inet_conn_established =        selinux_inet_conn_established,
5733         .req_classify_flow =            selinux_req_classify_flow,
5734
5735 #ifdef CONFIG_SECURITY_NETWORK_XFRM
5736         .xfrm_policy_alloc_security =   selinux_xfrm_policy_alloc,
5737         .xfrm_policy_clone_security =   selinux_xfrm_policy_clone,
5738         .xfrm_policy_free_security =    selinux_xfrm_policy_free,
5739         .xfrm_policy_delete_security =  selinux_xfrm_policy_delete,
5740         .xfrm_state_alloc_security =    selinux_xfrm_state_alloc,
5741         .xfrm_state_free_security =     selinux_xfrm_state_free,
5742         .xfrm_state_delete_security =   selinux_xfrm_state_delete,
5743         .xfrm_policy_lookup =           selinux_xfrm_policy_lookup,
5744         .xfrm_state_pol_flow_match =    selinux_xfrm_state_pol_flow_match,
5745         .xfrm_decode_session =          selinux_xfrm_decode_session,
5746 #endif
5747
5748 #ifdef CONFIG_KEYS
5749         .key_alloc =                    selinux_key_alloc,
5750         .key_free =                     selinux_key_free,
5751         .key_permission =               selinux_key_permission,
5752         .key_getsecurity =              selinux_key_getsecurity,
5753 #endif
5754
5755 #ifdef CONFIG_AUDIT
5756         .audit_rule_init =              selinux_audit_rule_init,
5757         .audit_rule_known =             selinux_audit_rule_known,
5758         .audit_rule_match =             selinux_audit_rule_match,
5759         .audit_rule_free =              selinux_audit_rule_free,
5760 #endif
5761 };
5762
5763 static __init int selinux_init(void)
5764 {
5765         if (!security_module_enable(&selinux_ops)) {
5766                 selinux_enabled = 0;
5767                 return 0;
5768         }
5769
5770         if (!selinux_enabled) {
5771                 printk(KERN_INFO "SELinux:  Disabled at boot.\n");
5772                 return 0;
5773         }
5774
5775         printk(KERN_INFO "SELinux:  Initializing.\n");
5776
5777         /* Set the security state for the initial task. */
5778         cred_init_security();
5779
5780         sel_inode_cache = kmem_cache_create("selinux_inode_security",
5781                                             sizeof(struct inode_security_struct),
5782                                             0, SLAB_PANIC, NULL);
5783         avc_init();
5784
5785         secondary_ops = security_ops;
5786         if (!secondary_ops)
5787                 panic("SELinux: No initial security operations\n");
5788         if (register_security(&selinux_ops))
5789                 panic("SELinux: Unable to register with kernel.\n");
5790
5791         if (selinux_enforcing)
5792                 printk(KERN_DEBUG "SELinux:  Starting in enforcing mode\n");
5793         else
5794                 printk(KERN_DEBUG "SELinux:  Starting in permissive mode\n");
5795
5796         return 0;
5797 }
5798
5799 void selinux_complete_init(void)
5800 {
5801         printk(KERN_DEBUG "SELinux:  Completing initialization.\n");
5802
5803         /* Set up any superblocks initialized prior to the policy load. */
5804         printk(KERN_DEBUG "SELinux:  Setting up existing superblocks.\n");
5805         spin_lock(&sb_lock);
5806         spin_lock(&sb_security_lock);
5807 next_sb:
5808         if (!list_empty(&superblock_security_head)) {
5809                 struct superblock_security_struct *sbsec =
5810                                 list_entry(superblock_security_head.next,
5811                                            struct superblock_security_struct,
5812                                            list);
5813                 struct super_block *sb = sbsec->sb;
5814                 sb->s_count++;
5815                 spin_unlock(&sb_security_lock);
5816                 spin_unlock(&sb_lock);
5817                 down_read(&sb->s_umount);
5818                 if (sb->s_root)
5819                         superblock_doinit(sb, NULL);
5820                 drop_super(sb);
5821                 spin_lock(&sb_lock);
5822                 spin_lock(&sb_security_lock);
5823                 list_del_init(&sbsec->list);
5824                 goto next_sb;
5825         }
5826         spin_unlock(&sb_security_lock);
5827         spin_unlock(&sb_lock);
5828 }
5829
5830 /* SELinux requires early initialization in order to label
5831    all processes and objects when they are created. */
5832 security_initcall(selinux_init);
5833
5834 #if defined(CONFIG_NETFILTER)
5835
5836 static struct nf_hook_ops selinux_ipv4_ops[] = {
5837         {
5838                 .hook =         selinux_ipv4_postroute,
5839                 .owner =        THIS_MODULE,
5840                 .pf =           PF_INET,
5841                 .hooknum =      NF_INET_POST_ROUTING,
5842                 .priority =     NF_IP_PRI_SELINUX_LAST,
5843         },
5844         {
5845                 .hook =         selinux_ipv4_forward,
5846                 .owner =        THIS_MODULE,
5847                 .pf =           PF_INET,
5848                 .hooknum =      NF_INET_FORWARD,
5849                 .priority =     NF_IP_PRI_SELINUX_FIRST,
5850         },
5851         {
5852                 .hook =         selinux_ipv4_output,
5853                 .owner =        THIS_MODULE,
5854                 .pf =           PF_INET,
5855                 .hooknum =      NF_INET_LOCAL_OUT,
5856                 .priority =     NF_IP_PRI_SELINUX_FIRST,
5857         }
5858 };
5859
5860 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
5861
5862 static struct nf_hook_ops selinux_ipv6_ops[] = {
5863         {
5864                 .hook =         selinux_ipv6_postroute,
5865                 .owner =        THIS_MODULE,
5866                 .pf =           PF_INET6,
5867                 .hooknum =      NF_INET_POST_ROUTING,
5868                 .priority =     NF_IP6_PRI_SELINUX_LAST,
5869         },
5870         {
5871                 .hook =         selinux_ipv6_forward,
5872                 .owner =        THIS_MODULE,
5873                 .pf =           PF_INET6,
5874                 .hooknum =      NF_INET_FORWARD,
5875                 .priority =     NF_IP6_PRI_SELINUX_FIRST,
5876         }
5877 };
5878
5879 #endif  /* IPV6 */
5880
5881 static int __init selinux_nf_ip_init(void)
5882 {
5883         int err = 0;
5884
5885         if (!selinux_enabled)
5886                 goto out;
5887
5888         printk(KERN_DEBUG "SELinux:  Registering netfilter hooks\n");
5889
5890         err = nf_register_hooks(selinux_ipv4_ops, ARRAY_SIZE(selinux_ipv4_ops));
5891         if (err)
5892                 panic("SELinux: nf_register_hooks for IPv4: error %d\n", err);
5893
5894 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
5895         err = nf_register_hooks(selinux_ipv6_ops, ARRAY_SIZE(selinux_ipv6_ops));
5896         if (err)
5897                 panic("SELinux: nf_register_hooks for IPv6: error %d\n", err);
5898 #endif  /* IPV6 */
5899
5900 out:
5901         return err;
5902 }
5903
5904 __initcall(selinux_nf_ip_init);
5905
5906 #ifdef CONFIG_SECURITY_SELINUX_DISABLE
5907 static void selinux_nf_ip_exit(void)
5908 {
5909         printk(KERN_DEBUG "SELinux:  Unregistering netfilter hooks\n");
5910
5911         nf_unregister_hooks(selinux_ipv4_ops, ARRAY_SIZE(selinux_ipv4_ops));
5912 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
5913         nf_unregister_hooks(selinux_ipv6_ops, ARRAY_SIZE(selinux_ipv6_ops));
5914 #endif  /* IPV6 */
5915 }
5916 #endif
5917
5918 #else /* CONFIG_NETFILTER */
5919
5920 #ifdef CONFIG_SECURITY_SELINUX_DISABLE
5921 #define selinux_nf_ip_exit()
5922 #endif
5923
5924 #endif /* CONFIG_NETFILTER */
5925
5926 #ifdef CONFIG_SECURITY_SELINUX_DISABLE
5927 static int selinux_disabled;
5928
5929 int selinux_disable(void)
5930 {
5931         extern void exit_sel_fs(void);
5932
5933         if (ss_initialized) {
5934                 /* Not permitted after initial policy load. */
5935                 return -EINVAL;
5936         }
5937
5938         if (selinux_disabled) {
5939                 /* Only do this once. */
5940                 return -EINVAL;
5941         }
5942
5943         printk(KERN_INFO "SELinux:  Disabled at runtime.\n");
5944
5945         selinux_disabled = 1;
5946         selinux_enabled = 0;
5947
5948         /* Reset security_ops to the secondary module, dummy or capability. */
5949         security_ops = secondary_ops;
5950
5951         /* Unregister netfilter hooks. */
5952         selinux_nf_ip_exit();
5953
5954         /* Unregister selinuxfs. */
5955         exit_sel_fs();
5956
5957         return 0;
5958 }
5959 #endif