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         return may_link(dir, dentry, MAY_UNLINK);
2639 }
2640
2641 static int selinux_inode_symlink(struct inode *dir, struct dentry *dentry, const char *name)
2642 {
2643         return may_create(dir, dentry, SECCLASS_LNK_FILE);
2644 }
2645
2646 static int selinux_inode_mkdir(struct inode *dir, struct dentry *dentry, int mask)
2647 {
2648         return may_create(dir, dentry, SECCLASS_DIR);
2649 }
2650
2651 static int selinux_inode_rmdir(struct inode *dir, struct dentry *dentry)
2652 {
2653         return may_link(dir, dentry, MAY_RMDIR);
2654 }
2655
2656 static int selinux_inode_mknod(struct inode *dir, struct dentry *dentry, int mode, dev_t dev)
2657 {
2658         int rc;
2659
2660         rc = secondary_ops->inode_mknod(dir, dentry, mode, dev);
2661         if (rc)
2662                 return rc;
2663
2664         return may_create(dir, dentry, inode_mode_to_security_class(mode));
2665 }
2666
2667 static int selinux_inode_rename(struct inode *old_inode, struct dentry *old_dentry,
2668                                 struct inode *new_inode, struct dentry *new_dentry)
2669 {
2670         return may_rename(old_inode, old_dentry, new_inode, new_dentry);
2671 }
2672
2673 static int selinux_inode_readlink(struct dentry *dentry)
2674 {
2675         const struct cred *cred = current_cred();
2676
2677         return dentry_has_perm(cred, NULL, dentry, FILE__READ);
2678 }
2679
2680 static int selinux_inode_follow_link(struct dentry *dentry, struct nameidata *nameidata)
2681 {
2682         const struct cred *cred = current_cred();
2683         int rc;
2684
2685         rc = secondary_ops->inode_follow_link(dentry, nameidata);
2686         if (rc)
2687                 return rc;
2688         return dentry_has_perm(cred, NULL, dentry, FILE__READ);
2689 }
2690
2691 static int selinux_inode_permission(struct inode *inode, int mask)
2692 {
2693         const struct cred *cred = current_cred();
2694         int rc;
2695
2696         rc = secondary_ops->inode_permission(inode, mask);
2697         if (rc)
2698                 return rc;
2699
2700         if (!mask) {
2701                 /* No permission to check.  Existence test. */
2702                 return 0;
2703         }
2704
2705         return inode_has_perm(cred, inode,
2706                               file_mask_to_av(inode->i_mode, mask), NULL);
2707 }
2708
2709 static int selinux_inode_setattr(struct dentry *dentry, struct iattr *iattr)
2710 {
2711         const struct cred *cred = current_cred();
2712         int rc;
2713
2714         rc = secondary_ops->inode_setattr(dentry, iattr);
2715         if (rc)
2716                 return rc;
2717
2718         if (iattr->ia_valid & ATTR_FORCE)
2719                 return 0;
2720
2721         if (iattr->ia_valid & (ATTR_MODE | ATTR_UID | ATTR_GID |
2722                                ATTR_ATIME_SET | ATTR_MTIME_SET))
2723                 return dentry_has_perm(cred, NULL, dentry, FILE__SETATTR);
2724
2725         return dentry_has_perm(cred, NULL, dentry, FILE__WRITE);
2726 }
2727
2728 static int selinux_inode_getattr(struct vfsmount *mnt, struct dentry *dentry)
2729 {
2730         const struct cred *cred = current_cred();
2731
2732         return dentry_has_perm(cred, mnt, dentry, FILE__GETATTR);
2733 }
2734
2735 static int selinux_inode_setotherxattr(struct dentry *dentry, const char *name)
2736 {
2737         const struct cred *cred = current_cred();
2738
2739         if (!strncmp(name, XATTR_SECURITY_PREFIX,
2740                      sizeof XATTR_SECURITY_PREFIX - 1)) {
2741                 if (!strcmp(name, XATTR_NAME_CAPS)) {
2742                         if (!capable(CAP_SETFCAP))
2743                                 return -EPERM;
2744                 } else if (!capable(CAP_SYS_ADMIN)) {
2745                         /* A different attribute in the security namespace.
2746                            Restrict to administrator. */
2747                         return -EPERM;
2748                 }
2749         }
2750
2751         /* Not an attribute we recognize, so just check the
2752            ordinary setattr permission. */
2753         return dentry_has_perm(cred, NULL, dentry, FILE__SETATTR);
2754 }
2755
2756 static int selinux_inode_setxattr(struct dentry *dentry, const char *name,
2757                                   const void *value, size_t size, int flags)
2758 {
2759         struct inode *inode = dentry->d_inode;
2760         struct inode_security_struct *isec = inode->i_security;
2761         struct superblock_security_struct *sbsec;
2762         struct avc_audit_data ad;
2763         u32 newsid, sid = current_sid();
2764         int rc = 0;
2765
2766         if (strcmp(name, XATTR_NAME_SELINUX))
2767                 return selinux_inode_setotherxattr(dentry, name);
2768
2769         sbsec = inode->i_sb->s_security;
2770         if (!(sbsec->flags & SE_SBLABELSUPP))
2771                 return -EOPNOTSUPP;
2772
2773         if (!is_owner_or_cap(inode))
2774                 return -EPERM;
2775
2776         AVC_AUDIT_DATA_INIT(&ad, FS);
2777         ad.u.fs.path.dentry = dentry;
2778
2779         rc = avc_has_perm(sid, isec->sid, isec->sclass,
2780                           FILE__RELABELFROM, &ad);
2781         if (rc)
2782                 return rc;
2783
2784         rc = security_context_to_sid(value, size, &newsid);
2785         if (rc == -EINVAL) {
2786                 if (!capable(CAP_MAC_ADMIN))
2787                         return rc;
2788                 rc = security_context_to_sid_force(value, size, &newsid);
2789         }
2790         if (rc)
2791                 return rc;
2792
2793         rc = avc_has_perm(sid, newsid, isec->sclass,
2794                           FILE__RELABELTO, &ad);
2795         if (rc)
2796                 return rc;
2797
2798         rc = security_validate_transition(isec->sid, newsid, sid,
2799                                           isec->sclass);
2800         if (rc)
2801                 return rc;
2802
2803         return avc_has_perm(newsid,
2804                             sbsec->sid,
2805                             SECCLASS_FILESYSTEM,
2806                             FILESYSTEM__ASSOCIATE,
2807                             &ad);
2808 }
2809
2810 static void selinux_inode_post_setxattr(struct dentry *dentry, const char *name,
2811                                         const void *value, size_t size,
2812                                         int flags)
2813 {
2814         struct inode *inode = dentry->d_inode;
2815         struct inode_security_struct *isec = inode->i_security;
2816         u32 newsid;
2817         int rc;
2818
2819         if (strcmp(name, XATTR_NAME_SELINUX)) {
2820                 /* Not an attribute we recognize, so nothing to do. */
2821                 return;
2822         }
2823
2824         rc = security_context_to_sid_force(value, size, &newsid);
2825         if (rc) {
2826                 printk(KERN_ERR "SELinux:  unable to map context to SID"
2827                        "for (%s, %lu), rc=%d\n",
2828                        inode->i_sb->s_id, inode->i_ino, -rc);
2829                 return;
2830         }
2831
2832         isec->sid = newsid;
2833         return;
2834 }
2835
2836 static int selinux_inode_getxattr(struct dentry *dentry, const char *name)
2837 {
2838         const struct cred *cred = current_cred();
2839
2840         return dentry_has_perm(cred, NULL, dentry, FILE__GETATTR);
2841 }
2842
2843 static int selinux_inode_listxattr(struct dentry *dentry)
2844 {
2845         const struct cred *cred = current_cred();
2846
2847         return dentry_has_perm(cred, NULL, dentry, FILE__GETATTR);
2848 }
2849
2850 static int selinux_inode_removexattr(struct dentry *dentry, const char *name)
2851 {
2852         if (strcmp(name, XATTR_NAME_SELINUX))
2853                 return selinux_inode_setotherxattr(dentry, name);
2854
2855         /* No one is allowed to remove a SELinux security label.
2856            You can change the label, but all data must be labeled. */
2857         return -EACCES;
2858 }
2859
2860 /*
2861  * Copy the inode security context value to the user.
2862  *
2863  * Permission check is handled by selinux_inode_getxattr hook.
2864  */
2865 static int selinux_inode_getsecurity(const struct inode *inode, const char *name, void **buffer, bool alloc)
2866 {
2867         u32 size;
2868         int error;
2869         char *context = NULL;
2870         struct inode_security_struct *isec = inode->i_security;
2871
2872         if (strcmp(name, XATTR_SELINUX_SUFFIX))
2873                 return -EOPNOTSUPP;
2874
2875         /*
2876          * If the caller has CAP_MAC_ADMIN, then get the raw context
2877          * value even if it is not defined by current policy; otherwise,
2878          * use the in-core value under current policy.
2879          * Use the non-auditing forms of the permission checks since
2880          * getxattr may be called by unprivileged processes commonly
2881          * and lack of permission just means that we fall back to the
2882          * in-core context value, not a denial.
2883          */
2884         error = selinux_capable(current, current_cred(), CAP_MAC_ADMIN,
2885                                 SECURITY_CAP_NOAUDIT);
2886         if (!error)
2887                 error = security_sid_to_context_force(isec->sid, &context,
2888                                                       &size);
2889         else
2890                 error = security_sid_to_context(isec->sid, &context, &size);
2891         if (error)
2892                 return error;
2893         error = size;
2894         if (alloc) {
2895                 *buffer = context;
2896                 goto out_nofree;
2897         }
2898         kfree(context);
2899 out_nofree:
2900         return error;
2901 }
2902
2903 static int selinux_inode_setsecurity(struct inode *inode, const char *name,
2904                                      const void *value, size_t size, int flags)
2905 {
2906         struct inode_security_struct *isec = inode->i_security;
2907         u32 newsid;
2908         int rc;
2909
2910         if (strcmp(name, XATTR_SELINUX_SUFFIX))
2911                 return -EOPNOTSUPP;
2912
2913         if (!value || !size)
2914                 return -EACCES;
2915
2916         rc = security_context_to_sid((void *)value, size, &newsid);
2917         if (rc)
2918                 return rc;
2919
2920         isec->sid = newsid;
2921         return 0;
2922 }
2923
2924 static int selinux_inode_listsecurity(struct inode *inode, char *buffer, size_t buffer_size)
2925 {
2926         const int len = sizeof(XATTR_NAME_SELINUX);
2927         if (buffer && len <= buffer_size)
2928                 memcpy(buffer, XATTR_NAME_SELINUX, len);
2929         return len;
2930 }
2931
2932 static int selinux_inode_need_killpriv(struct dentry *dentry)
2933 {
2934         return secondary_ops->inode_need_killpriv(dentry);
2935 }
2936
2937 static int selinux_inode_killpriv(struct dentry *dentry)
2938 {
2939         return secondary_ops->inode_killpriv(dentry);
2940 }
2941
2942 static void selinux_inode_getsecid(const struct inode *inode, u32 *secid)
2943 {
2944         struct inode_security_struct *isec = inode->i_security;
2945         *secid = isec->sid;
2946 }
2947
2948 /* file security operations */
2949
2950 static int selinux_revalidate_file_permission(struct file *file, int mask)
2951 {
2952         const struct cred *cred = current_cred();
2953         int rc;
2954         struct inode *inode = file->f_path.dentry->d_inode;
2955
2956         if (!mask) {
2957                 /* No permission to check.  Existence test. */
2958                 return 0;
2959         }
2960
2961         /* file_mask_to_av won't add FILE__WRITE if MAY_APPEND is set */
2962         if ((file->f_flags & O_APPEND) && (mask & MAY_WRITE))
2963                 mask |= MAY_APPEND;
2964
2965         rc = file_has_perm(cred, file,
2966                            file_mask_to_av(inode->i_mode, mask));
2967         if (rc)
2968                 return rc;
2969
2970         return selinux_netlbl_inode_permission(inode, mask);
2971 }
2972
2973 static int selinux_file_permission(struct file *file, int mask)
2974 {
2975         struct inode *inode = file->f_path.dentry->d_inode;
2976         struct file_security_struct *fsec = file->f_security;
2977         struct inode_security_struct *isec = inode->i_security;
2978         u32 sid = current_sid();
2979
2980         if (!mask) {
2981                 /* No permission to check.  Existence test. */
2982                 return 0;
2983         }
2984
2985         if (sid == fsec->sid && fsec->isid == isec->sid
2986             && fsec->pseqno == avc_policy_seqno())
2987                 return selinux_netlbl_inode_permission(inode, mask);
2988
2989         return selinux_revalidate_file_permission(file, mask);
2990 }
2991
2992 static int selinux_file_alloc_security(struct file *file)
2993 {
2994         return file_alloc_security(file);
2995 }
2996
2997 static void selinux_file_free_security(struct file *file)
2998 {
2999         file_free_security(file);
3000 }
3001
3002 static int selinux_file_ioctl(struct file *file, unsigned int cmd,
3003                               unsigned long arg)
3004 {
3005         const struct cred *cred = current_cred();
3006         u32 av = 0;
3007
3008         if (_IOC_DIR(cmd) & _IOC_WRITE)
3009                 av |= FILE__WRITE;
3010         if (_IOC_DIR(cmd) & _IOC_READ)
3011                 av |= FILE__READ;
3012         if (!av)
3013                 av = FILE__IOCTL;
3014
3015         return file_has_perm(cred, file, av);
3016 }
3017
3018 static int file_map_prot_check(struct file *file, unsigned long prot, int shared)
3019 {
3020         const struct cred *cred = current_cred();
3021         int rc = 0;
3022
3023 #ifndef CONFIG_PPC32
3024         if ((prot & PROT_EXEC) && (!file || (!shared && (prot & PROT_WRITE)))) {
3025                 /*
3026                  * We are making executable an anonymous mapping or a
3027                  * private file mapping that will also be writable.
3028                  * This has an additional check.
3029                  */
3030                 rc = cred_has_perm(cred, cred, PROCESS__EXECMEM);
3031                 if (rc)
3032                         goto error;
3033         }
3034 #endif
3035
3036         if (file) {
3037                 /* read access is always possible with a mapping */
3038                 u32 av = FILE__READ;
3039
3040                 /* write access only matters if the mapping is shared */
3041                 if (shared && (prot & PROT_WRITE))
3042                         av |= FILE__WRITE;
3043
3044                 if (prot & PROT_EXEC)
3045                         av |= FILE__EXECUTE;
3046
3047                 return file_has_perm(cred, file, av);
3048         }
3049
3050 error:
3051         return rc;
3052 }
3053
3054 static int selinux_file_mmap(struct file *file, unsigned long reqprot,
3055                              unsigned long prot, unsigned long flags,
3056                              unsigned long addr, unsigned long addr_only)
3057 {
3058         int rc = 0;
3059         u32 sid = current_sid();
3060
3061         if (addr < mmap_min_addr)
3062                 rc = avc_has_perm(sid, sid, SECCLASS_MEMPROTECT,
3063                                   MEMPROTECT__MMAP_ZERO, NULL);
3064         if (rc || addr_only)
3065                 return rc;
3066
3067         if (selinux_checkreqprot)
3068                 prot = reqprot;
3069
3070         return file_map_prot_check(file, prot,
3071                                    (flags & MAP_TYPE) == MAP_SHARED);
3072 }
3073
3074 static int selinux_file_mprotect(struct vm_area_struct *vma,
3075                                  unsigned long reqprot,
3076                                  unsigned long prot)
3077 {
3078         const struct cred *cred = current_cred();
3079         int rc;
3080
3081         rc = secondary_ops->file_mprotect(vma, reqprot, prot);
3082         if (rc)
3083                 return rc;
3084
3085         if (selinux_checkreqprot)
3086                 prot = reqprot;
3087
3088 #ifndef CONFIG_PPC32
3089         if ((prot & PROT_EXEC) && !(vma->vm_flags & VM_EXEC)) {
3090                 rc = 0;
3091                 if (vma->vm_start >= vma->vm_mm->start_brk &&
3092                     vma->vm_end <= vma->vm_mm->brk) {
3093                         rc = cred_has_perm(cred, cred, PROCESS__EXECHEAP);
3094                 } else if (!vma->vm_file &&
3095                            vma->vm_start <= vma->vm_mm->start_stack &&
3096                            vma->vm_end >= vma->vm_mm->start_stack) {
3097                         rc = current_has_perm(current, PROCESS__EXECSTACK);
3098                 } else if (vma->vm_file && vma->anon_vma) {
3099                         /*
3100                          * We are making executable a file mapping that has
3101                          * had some COW done. Since pages might have been
3102                          * written, check ability to execute the possibly
3103                          * modified content.  This typically should only
3104                          * occur for text relocations.
3105                          */
3106                         rc = file_has_perm(cred, vma->vm_file, FILE__EXECMOD);
3107                 }
3108                 if (rc)
3109                         return rc;
3110         }
3111 #endif
3112
3113         return file_map_prot_check(vma->vm_file, prot, vma->vm_flags&VM_SHARED);
3114 }
3115
3116 static int selinux_file_lock(struct file *file, unsigned int cmd)
3117 {
3118         const struct cred *cred = current_cred();
3119
3120         return file_has_perm(cred, file, FILE__LOCK);
3121 }
3122
3123 static int selinux_file_fcntl(struct file *file, unsigned int cmd,
3124                               unsigned long arg)
3125 {
3126         const struct cred *cred = current_cred();
3127         int err = 0;
3128
3129         switch (cmd) {
3130         case F_SETFL:
3131                 if (!file->f_path.dentry || !file->f_path.dentry->d_inode) {
3132                         err = -EINVAL;
3133                         break;
3134                 }
3135
3136                 if ((file->f_flags & O_APPEND) && !(arg & O_APPEND)) {
3137                         err = file_has_perm(cred, file, FILE__WRITE);
3138                         break;
3139                 }
3140                 /* fall through */
3141         case F_SETOWN:
3142         case F_SETSIG:
3143         case F_GETFL:
3144         case F_GETOWN:
3145         case F_GETSIG:
3146                 /* Just check FD__USE permission */
3147                 err = file_has_perm(cred, file, 0);
3148                 break;
3149         case F_GETLK:
3150         case F_SETLK:
3151         case F_SETLKW:
3152 #if BITS_PER_LONG == 32
3153         case F_GETLK64:
3154         case F_SETLK64:
3155         case F_SETLKW64:
3156 #endif
3157                 if (!file->f_path.dentry || !file->f_path.dentry->d_inode) {
3158                         err = -EINVAL;
3159                         break;
3160                 }
3161                 err = file_has_perm(cred, file, FILE__LOCK);
3162                 break;
3163         }
3164
3165         return err;
3166 }
3167
3168 static int selinux_file_set_fowner(struct file *file)
3169 {
3170         struct file_security_struct *fsec;
3171
3172         fsec = file->f_security;
3173         fsec->fown_sid = current_sid();
3174
3175         return 0;
3176 }
3177
3178 static int selinux_file_send_sigiotask(struct task_struct *tsk,
3179                                        struct fown_struct *fown, int signum)
3180 {
3181         struct file *file;
3182         u32 sid = current_sid();
3183         u32 perm;
3184         struct file_security_struct *fsec;
3185
3186         /* struct fown_struct is never outside the context of a struct file */
3187         file = container_of(fown, struct file, f_owner);
3188
3189         fsec = file->f_security;
3190
3191         if (!signum)
3192                 perm = signal_to_av(SIGIO); /* as per send_sigio_to_task */
3193         else
3194                 perm = signal_to_av(signum);
3195
3196         return avc_has_perm(fsec->fown_sid, sid,
3197                             SECCLASS_PROCESS, perm, NULL);
3198 }
3199
3200 static int selinux_file_receive(struct file *file)
3201 {
3202         const struct cred *cred = current_cred();
3203
3204         return file_has_perm(cred, file, file_to_av(file));
3205 }
3206
3207 static int selinux_dentry_open(struct file *file, const struct cred *cred)
3208 {
3209         struct file_security_struct *fsec;
3210         struct inode *inode;
3211         struct inode_security_struct *isec;
3212
3213         inode = file->f_path.dentry->d_inode;
3214         fsec = file->f_security;
3215         isec = inode->i_security;
3216         /*
3217          * Save inode label and policy sequence number
3218          * at open-time so that selinux_file_permission
3219          * can determine whether revalidation is necessary.
3220          * Task label is already saved in the file security
3221          * struct as its SID.
3222          */
3223         fsec->isid = isec->sid;
3224         fsec->pseqno = avc_policy_seqno();
3225         /*
3226          * Since the inode label or policy seqno may have changed
3227          * between the selinux_inode_permission check and the saving
3228          * of state above, recheck that access is still permitted.
3229          * Otherwise, access might never be revalidated against the
3230          * new inode label or new policy.
3231          * This check is not redundant - do not remove.
3232          */
3233         return inode_has_perm(cred, inode, open_file_to_av(file), NULL);
3234 }
3235
3236 /* task security operations */
3237
3238 static int selinux_task_create(unsigned long clone_flags)
3239 {
3240         int rc;
3241
3242         rc = secondary_ops->task_create(clone_flags);
3243         if (rc)
3244                 return rc;
3245
3246         return current_has_perm(current, PROCESS__FORK);
3247 }
3248
3249 /*
3250  * detach and free the LSM part of a set of credentials
3251  */
3252 static void selinux_cred_free(struct cred *cred)
3253 {
3254         struct task_security_struct *tsec = cred->security;
3255         cred->security = NULL;
3256         kfree(tsec);
3257 }
3258
3259 /*
3260  * prepare a new set of credentials for modification
3261  */
3262 static int selinux_cred_prepare(struct cred *new, const struct cred *old,
3263                                 gfp_t gfp)
3264 {
3265         const struct task_security_struct *old_tsec;
3266         struct task_security_struct *tsec;
3267
3268         old_tsec = old->security;
3269
3270         tsec = kmemdup(old_tsec, sizeof(struct task_security_struct), gfp);
3271         if (!tsec)
3272                 return -ENOMEM;
3273
3274         new->security = tsec;
3275         return 0;
3276 }
3277
3278 /*
3279  * commit new credentials
3280  */
3281 static void selinux_cred_commit(struct cred *new, const struct cred *old)
3282 {
3283         secondary_ops->cred_commit(new, old);
3284 }
3285
3286 /*
3287  * set the security data for a kernel service
3288  * - all the creation contexts are set to unlabelled
3289  */
3290 static int selinux_kernel_act_as(struct cred *new, u32 secid)
3291 {
3292         struct task_security_struct *tsec = new->security;
3293         u32 sid = current_sid();
3294         int ret;
3295
3296         ret = avc_has_perm(sid, secid,
3297                            SECCLASS_KERNEL_SERVICE,
3298                            KERNEL_SERVICE__USE_AS_OVERRIDE,
3299                            NULL);
3300         if (ret == 0) {
3301                 tsec->sid = secid;
3302                 tsec->create_sid = 0;
3303                 tsec->keycreate_sid = 0;
3304                 tsec->sockcreate_sid = 0;
3305         }
3306         return ret;
3307 }
3308
3309 /*
3310  * set the file creation context in a security record to the same as the
3311  * objective context of the specified inode
3312  */
3313 static int selinux_kernel_create_files_as(struct cred *new, struct inode *inode)
3314 {
3315         struct inode_security_struct *isec = inode->i_security;
3316         struct task_security_struct *tsec = new->security;
3317         u32 sid = current_sid();
3318         int ret;
3319
3320         ret = avc_has_perm(sid, isec->sid,
3321                            SECCLASS_KERNEL_SERVICE,
3322                            KERNEL_SERVICE__CREATE_FILES_AS,
3323                            NULL);
3324
3325         if (ret == 0)
3326                 tsec->create_sid = isec->sid;
3327         return 0;
3328 }
3329
3330 static int selinux_task_setuid(uid_t id0, uid_t id1, uid_t id2, int flags)
3331 {
3332         /* Since setuid only affects the current process, and
3333            since the SELinux controls are not based on the Linux
3334            identity attributes, SELinux does not need to control
3335            this operation.  However, SELinux does control the use
3336            of the CAP_SETUID and CAP_SETGID capabilities using the
3337            capable hook. */
3338         return 0;
3339 }
3340
3341 static int selinux_task_fix_setuid(struct cred *new, const struct cred *old,
3342                                    int flags)
3343 {
3344         return secondary_ops->task_fix_setuid(new, old, flags);
3345 }
3346
3347 static int selinux_task_setgid(gid_t id0, gid_t id1, gid_t id2, int flags)
3348 {
3349         /* See the comment for setuid above. */
3350         return 0;
3351 }
3352
3353 static int selinux_task_setpgid(struct task_struct *p, pid_t pgid)
3354 {
3355         return current_has_perm(p, PROCESS__SETPGID);
3356 }
3357
3358 static int selinux_task_getpgid(struct task_struct *p)
3359 {
3360         return current_has_perm(p, PROCESS__GETPGID);
3361 }
3362
3363 static int selinux_task_getsid(struct task_struct *p)
3364 {
3365         return current_has_perm(p, PROCESS__GETSESSION);
3366 }
3367
3368 static void selinux_task_getsecid(struct task_struct *p, u32 *secid)
3369 {
3370         *secid = task_sid(p);
3371 }
3372
3373 static int selinux_task_setgroups(struct group_info *group_info)
3374 {
3375         /* See the comment for setuid above. */
3376         return 0;
3377 }
3378
3379 static int selinux_task_setnice(struct task_struct *p, int nice)
3380 {
3381         int rc;
3382
3383         rc = secondary_ops->task_setnice(p, nice);
3384         if (rc)
3385                 return rc;
3386
3387         return current_has_perm(p, PROCESS__SETSCHED);
3388 }
3389
3390 static int selinux_task_setioprio(struct task_struct *p, int ioprio)
3391 {
3392         int rc;
3393
3394         rc = secondary_ops->task_setioprio(p, ioprio);
3395         if (rc)
3396                 return rc;
3397
3398         return current_has_perm(p, PROCESS__SETSCHED);
3399 }
3400
3401 static int selinux_task_getioprio(struct task_struct *p)
3402 {
3403         return current_has_perm(p, PROCESS__GETSCHED);
3404 }
3405
3406 static int selinux_task_setrlimit(unsigned int resource, struct rlimit *new_rlim)
3407 {
3408         struct rlimit *old_rlim = current->signal->rlim + resource;
3409         int rc;
3410
3411         rc = secondary_ops->task_setrlimit(resource, new_rlim);
3412         if (rc)
3413                 return rc;
3414
3415         /* Control the ability to change the hard limit (whether
3416            lowering or raising it), so that the hard limit can
3417            later be used as a safe reset point for the soft limit
3418            upon context transitions.  See selinux_bprm_committing_creds. */
3419         if (old_rlim->rlim_max != new_rlim->rlim_max)
3420                 return current_has_perm(current, PROCESS__SETRLIMIT);
3421
3422         return 0;
3423 }
3424
3425 static int selinux_task_setscheduler(struct task_struct *p, int policy, struct sched_param *lp)
3426 {
3427         int rc;
3428
3429         rc = secondary_ops->task_setscheduler(p, policy, lp);
3430         if (rc)
3431                 return rc;
3432
3433         return current_has_perm(p, PROCESS__SETSCHED);
3434 }
3435
3436 static int selinux_task_getscheduler(struct task_struct *p)
3437 {
3438         return current_has_perm(p, PROCESS__GETSCHED);
3439 }
3440
3441 static int selinux_task_movememory(struct task_struct *p)
3442 {
3443         return current_has_perm(p, PROCESS__SETSCHED);
3444 }
3445
3446 static int selinux_task_kill(struct task_struct *p, struct siginfo *info,
3447                                 int sig, u32 secid)
3448 {
3449         u32 perm;
3450         int rc;
3451
3452         rc = secondary_ops->task_kill(p, info, sig, secid);
3453         if (rc)
3454                 return rc;
3455
3456         if (!sig)
3457                 perm = PROCESS__SIGNULL; /* null signal; existence test */
3458         else
3459                 perm = signal_to_av(sig);
3460         if (secid)
3461                 rc = avc_has_perm(secid, task_sid(p),
3462                                   SECCLASS_PROCESS, perm, NULL);
3463         else
3464                 rc = current_has_perm(p, perm);
3465         return rc;
3466 }
3467
3468 static int selinux_task_prctl(int option,
3469                               unsigned long arg2,
3470                               unsigned long arg3,
3471                               unsigned long arg4,
3472                               unsigned long arg5)
3473 {
3474         /* The current prctl operations do not appear to require
3475            any SELinux controls since they merely observe or modify
3476            the state of the current process. */
3477         return secondary_ops->task_prctl(option, arg2, arg3, arg4, arg5);
3478 }
3479
3480 static int selinux_task_wait(struct task_struct *p)
3481 {
3482         return task_has_perm(p, current, PROCESS__SIGCHLD);
3483 }
3484
3485 static void selinux_task_to_inode(struct task_struct *p,
3486                                   struct inode *inode)
3487 {
3488         struct inode_security_struct *isec = inode->i_security;
3489         u32 sid = task_sid(p);
3490
3491         isec->sid = sid;
3492         isec->initialized = 1;
3493 }
3494
3495 /* Returns error only if unable to parse addresses */
3496 static int selinux_parse_skb_ipv4(struct sk_buff *skb,
3497                         struct avc_audit_data *ad, u8 *proto)
3498 {
3499         int offset, ihlen, ret = -EINVAL;
3500         struct iphdr _iph, *ih;
3501
3502         offset = skb_network_offset(skb);
3503         ih = skb_header_pointer(skb, offset, sizeof(_iph), &_iph);
3504         if (ih == NULL)
3505                 goto out;
3506
3507         ihlen = ih->ihl * 4;
3508         if (ihlen < sizeof(_iph))
3509                 goto out;
3510
3511         ad->u.net.v4info.saddr = ih->saddr;
3512         ad->u.net.v4info.daddr = ih->daddr;
3513         ret = 0;
3514
3515         if (proto)
3516                 *proto = ih->protocol;
3517
3518         switch (ih->protocol) {
3519         case IPPROTO_TCP: {
3520                 struct tcphdr _tcph, *th;
3521
3522                 if (ntohs(ih->frag_off) & IP_OFFSET)
3523                         break;
3524
3525                 offset += ihlen;
3526                 th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph);
3527                 if (th == NULL)
3528                         break;
3529
3530                 ad->u.net.sport = th->source;
3531                 ad->u.net.dport = th->dest;
3532                 break;
3533         }
3534
3535         case IPPROTO_UDP: {
3536                 struct udphdr _udph, *uh;
3537
3538                 if (ntohs(ih->frag_off) & IP_OFFSET)
3539                         break;
3540
3541                 offset += ihlen;
3542                 uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph);
3543                 if (uh == NULL)
3544                         break;
3545
3546                 ad->u.net.sport = uh->source;
3547                 ad->u.net.dport = uh->dest;
3548                 break;
3549         }
3550
3551         case IPPROTO_DCCP: {
3552                 struct dccp_hdr _dccph, *dh;
3553
3554                 if (ntohs(ih->frag_off) & IP_OFFSET)
3555                         break;
3556
3557                 offset += ihlen;
3558                 dh = skb_header_pointer(skb, offset, sizeof(_dccph), &_dccph);
3559                 if (dh == NULL)
3560                         break;
3561
3562                 ad->u.net.sport = dh->dccph_sport;
3563                 ad->u.net.dport = dh->dccph_dport;
3564                 break;
3565         }
3566
3567         default:
3568                 break;
3569         }
3570 out:
3571         return ret;
3572 }
3573
3574 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
3575
3576 /* Returns error only if unable to parse addresses */
3577 static int selinux_parse_skb_ipv6(struct sk_buff *skb,
3578                         struct avc_audit_data *ad, u8 *proto)
3579 {
3580         u8 nexthdr;
3581         int ret = -EINVAL, offset;
3582         struct ipv6hdr _ipv6h, *ip6;
3583
3584         offset = skb_network_offset(skb);
3585         ip6 = skb_header_pointer(skb, offset, sizeof(_ipv6h), &_ipv6h);
3586         if (ip6 == NULL)
3587                 goto out;
3588
3589         ipv6_addr_copy(&ad->u.net.v6info.saddr, &ip6->saddr);
3590         ipv6_addr_copy(&ad->u.net.v6info.daddr, &ip6->daddr);
3591         ret = 0;
3592
3593         nexthdr = ip6->nexthdr;
3594         offset += sizeof(_ipv6h);
3595         offset = ipv6_skip_exthdr(skb, offset, &nexthdr);
3596         if (offset < 0)
3597                 goto out;
3598
3599         if (proto)
3600                 *proto = nexthdr;
3601
3602         switch (nexthdr) {
3603         case IPPROTO_TCP: {
3604                 struct tcphdr _tcph, *th;
3605
3606                 th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph);
3607                 if (th == NULL)
3608                         break;
3609
3610                 ad->u.net.sport = th->source;
3611                 ad->u.net.dport = th->dest;
3612                 break;
3613         }
3614
3615         case IPPROTO_UDP: {
3616                 struct udphdr _udph, *uh;
3617
3618                 uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph);
3619                 if (uh == NULL)
3620                         break;
3621
3622                 ad->u.net.sport = uh->source;
3623                 ad->u.net.dport = uh->dest;
3624                 break;
3625         }
3626
3627         case IPPROTO_DCCP: {
3628                 struct dccp_hdr _dccph, *dh;
3629
3630                 dh = skb_header_pointer(skb, offset, sizeof(_dccph), &_dccph);
3631                 if (dh == NULL)
3632                         break;
3633
3634                 ad->u.net.sport = dh->dccph_sport;
3635                 ad->u.net.dport = dh->dccph_dport;
3636                 break;
3637         }
3638
3639         /* includes fragments */
3640         default:
3641                 break;
3642         }
3643 out:
3644         return ret;
3645 }
3646
3647 #endif /* IPV6 */
3648
3649 static int selinux_parse_skb(struct sk_buff *skb, struct avc_audit_data *ad,
3650                              char **_addrp, int src, u8 *proto)
3651 {
3652         char *addrp;
3653         int ret;
3654
3655         switch (ad->u.net.family) {
3656         case PF_INET:
3657                 ret = selinux_parse_skb_ipv4(skb, ad, proto);
3658                 if (ret)
3659                         goto parse_error;
3660                 addrp = (char *)(src ? &ad->u.net.v4info.saddr :
3661                                        &ad->u.net.v4info.daddr);
3662                 goto okay;
3663
3664 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
3665         case PF_INET6:
3666                 ret = selinux_parse_skb_ipv6(skb, ad, proto);
3667                 if (ret)
3668                         goto parse_error;
3669                 addrp = (char *)(src ? &ad->u.net.v6info.saddr :
3670                                        &ad->u.net.v6info.daddr);
3671                 goto okay;
3672 #endif  /* IPV6 */
3673         default:
3674                 addrp = NULL;
3675                 goto okay;
3676         }
3677
3678 parse_error:
3679         printk(KERN_WARNING
3680                "SELinux: failure in selinux_parse_skb(),"
3681                " unable to parse packet\n");
3682         return ret;
3683
3684 okay:
3685         if (_addrp)
3686                 *_addrp = addrp;
3687         return 0;
3688 }
3689
3690 /**
3691  * selinux_skb_peerlbl_sid - Determine the peer label of a packet
3692  * @skb: the packet
3693  * @family: protocol family
3694  * @sid: the packet's peer label SID
3695  *
3696  * Description:
3697  * Check the various different forms of network peer labeling and determine
3698  * the peer label/SID for the packet; most of the magic actually occurs in
3699  * the security server function security_net_peersid_cmp().  The function
3700  * returns zero if the value in @sid is valid (although it may be SECSID_NULL)
3701  * or -EACCES if @sid is invalid due to inconsistencies with the different
3702  * peer labels.
3703  *
3704  */
3705 static int selinux_skb_peerlbl_sid(struct sk_buff *skb, u16 family, u32 *sid)
3706 {
3707         int err;
3708         u32 xfrm_sid;
3709         u32 nlbl_sid;
3710         u32 nlbl_type;
3711
3712         selinux_skb_xfrm_sid(skb, &xfrm_sid);
3713         selinux_netlbl_skbuff_getsid(skb, family, &nlbl_type, &nlbl_sid);
3714
3715         err = security_net_peersid_resolve(nlbl_sid, nlbl_type, xfrm_sid, sid);
3716         if (unlikely(err)) {
3717                 printk(KERN_WARNING
3718                        "SELinux: failure in selinux_skb_peerlbl_sid(),"
3719                        " unable to determine packet's peer label\n");
3720                 return -EACCES;
3721         }
3722
3723         return 0;
3724 }
3725
3726 /* socket security operations */
3727 static int socket_has_perm(struct task_struct *task, struct socket *sock,
3728                            u32 perms)
3729 {
3730         struct inode_security_struct *isec;
3731         struct avc_audit_data ad;
3732         u32 sid;
3733         int err = 0;
3734
3735         isec = SOCK_INODE(sock)->i_security;
3736
3737         if (isec->sid == SECINITSID_KERNEL)
3738                 goto out;
3739         sid = task_sid(task);
3740
3741         AVC_AUDIT_DATA_INIT(&ad, NET);
3742         ad.u.net.sk = sock->sk;
3743         err = avc_has_perm(sid, isec->sid, isec->sclass, perms, &ad);
3744
3745 out:
3746         return err;
3747 }
3748
3749 static int selinux_socket_create(int family, int type,
3750                                  int protocol, int kern)
3751 {
3752         const struct cred *cred = current_cred();
3753         const struct task_security_struct *tsec = cred->security;
3754         u32 sid, newsid;
3755         u16 secclass;
3756         int err = 0;
3757
3758         if (kern)
3759                 goto out;
3760
3761         sid = tsec->sid;
3762         newsid = tsec->sockcreate_sid ?: sid;
3763
3764         secclass = socket_type_to_security_class(family, type, protocol);
3765         err = avc_has_perm(sid, newsid, secclass, SOCKET__CREATE, NULL);
3766
3767 out:
3768         return err;
3769 }
3770
3771 static int selinux_socket_post_create(struct socket *sock, int family,
3772                                       int type, int protocol, int kern)
3773 {
3774         const struct cred *cred = current_cred();
3775         const struct task_security_struct *tsec = cred->security;
3776         struct inode_security_struct *isec;
3777         struct sk_security_struct *sksec;
3778         u32 sid, newsid;
3779         int err = 0;
3780
3781         sid = tsec->sid;
3782         newsid = tsec->sockcreate_sid;
3783
3784         isec = SOCK_INODE(sock)->i_security;
3785
3786         if (kern)
3787                 isec->sid = SECINITSID_KERNEL;
3788         else if (newsid)
3789                 isec->sid = newsid;
3790         else
3791                 isec->sid = sid;
3792
3793         isec->sclass = socket_type_to_security_class(family, type, protocol);
3794         isec->initialized = 1;
3795
3796         if (sock->sk) {
3797                 sksec = sock->sk->sk_security;
3798                 sksec->sid = isec->sid;
3799                 sksec->sclass = isec->sclass;
3800                 err = selinux_netlbl_socket_post_create(sock);
3801         }
3802
3803         return err;
3804 }
3805
3806 /* Range of port numbers used to automatically bind.
3807    Need to determine whether we should perform a name_bind
3808    permission check between the socket and the port number. */
3809
3810 static int selinux_socket_bind(struct socket *sock, struct sockaddr *address, int addrlen)
3811 {
3812         u16 family;
3813         int err;
3814
3815         err = socket_has_perm(current, sock, SOCKET__BIND);
3816         if (err)
3817                 goto out;
3818
3819         /*
3820          * If PF_INET or PF_INET6, check name_bind permission for the port.
3821          * Multiple address binding for SCTP is not supported yet: we just
3822          * check the first address now.
3823          */
3824         family = sock->sk->sk_family;
3825         if (family == PF_INET || family == PF_INET6) {
3826                 char *addrp;
3827                 struct inode_security_struct *isec;
3828                 struct avc_audit_data ad;
3829                 struct sockaddr_in *addr4 = NULL;
3830                 struct sockaddr_in6 *addr6 = NULL;
3831                 unsigned short snum;
3832                 struct sock *sk = sock->sk;
3833                 u32 sid, node_perm;
3834
3835                 isec = SOCK_INODE(sock)->i_security;
3836
3837                 if (family == PF_INET) {
3838                         addr4 = (struct sockaddr_in *)address;
3839                         snum = ntohs(addr4->sin_port);
3840                         addrp = (char *)&addr4->sin_addr.s_addr;
3841                 } else {
3842                         addr6 = (struct sockaddr_in6 *)address;
3843                         snum = ntohs(addr6->sin6_port);
3844                         addrp = (char *)&addr6->sin6_addr.s6_addr;
3845                 }
3846
3847                 if (snum) {
3848                         int low, high;
3849
3850                         inet_get_local_port_range(&low, &high);
3851
3852                         if (snum < max(PROT_SOCK, low) || snum > high) {
3853                                 err = sel_netport_sid(sk->sk_protocol,
3854                                                       snum, &sid);
3855                                 if (err)
3856                                         goto out;
3857                                 AVC_AUDIT_DATA_INIT(&ad, NET);
3858                                 ad.u.net.sport = htons(snum);
3859                                 ad.u.net.family = family;
3860                                 err = avc_has_perm(isec->sid, sid,
3861                                                    isec->sclass,
3862                                                    SOCKET__NAME_BIND, &ad);
3863                                 if (err)
3864                                         goto out;
3865                         }
3866                 }
3867
3868                 switch (isec->sclass) {
3869                 case SECCLASS_TCP_SOCKET:
3870                         node_perm = TCP_SOCKET__NODE_BIND;
3871                         break;
3872
3873                 case SECCLASS_UDP_SOCKET:
3874                         node_perm = UDP_SOCKET__NODE_BIND;
3875                         break;
3876
3877                 case SECCLASS_DCCP_SOCKET:
3878                         node_perm = DCCP_SOCKET__NODE_BIND;
3879                         break;
3880
3881                 default:
3882                         node_perm = RAWIP_SOCKET__NODE_BIND;
3883                         break;
3884                 }
3885
3886                 err = sel_netnode_sid(addrp, family, &sid);
3887                 if (err)
3888                         goto out;
3889
3890                 AVC_AUDIT_DATA_INIT(&ad, NET);
3891                 ad.u.net.sport = htons(snum);
3892                 ad.u.net.family = family;
3893
3894                 if (family == PF_INET)
3895                         ad.u.net.v4info.saddr = addr4->sin_addr.s_addr;
3896                 else
3897                         ipv6_addr_copy(&ad.u.net.v6info.saddr, &addr6->sin6_addr);
3898
3899                 err = avc_has_perm(isec->sid, sid,
3900                                    isec->sclass, node_perm, &ad);
3901                 if (err)
3902                         goto out;
3903         }
3904 out:
3905         return err;
3906 }
3907
3908 static int selinux_socket_connect(struct socket *sock, struct sockaddr *address, int addrlen)
3909 {
3910         struct sock *sk = sock->sk;
3911         struct inode_security_struct *isec;
3912         int err;
3913
3914         err = socket_has_perm(current, sock, SOCKET__CONNECT);
3915         if (err)
3916                 return err;
3917
3918         /*
3919          * If a TCP or DCCP socket, check name_connect permission for the port.
3920          */
3921         isec = SOCK_INODE(sock)->i_security;
3922         if (isec->sclass == SECCLASS_TCP_SOCKET ||
3923             isec->sclass == SECCLASS_DCCP_SOCKET) {
3924                 struct avc_audit_data ad;
3925                 struct sockaddr_in *addr4 = NULL;
3926                 struct sockaddr_in6 *addr6 = NULL;
3927                 unsigned short snum;
3928                 u32 sid, perm;
3929
3930                 if (sk->sk_family == PF_INET) {
3931                         addr4 = (struct sockaddr_in *)address;
3932                         if (addrlen < sizeof(struct sockaddr_in))
3933                                 return -EINVAL;
3934                         snum = ntohs(addr4->sin_port);
3935                 } else {
3936                         addr6 = (struct sockaddr_in6 *)address;
3937                         if (addrlen < SIN6_LEN_RFC2133)
3938                                 return -EINVAL;
3939                         snum = ntohs(addr6->sin6_port);
3940                 }
3941
3942                 err = sel_netport_sid(sk->sk_protocol, snum, &sid);
3943                 if (err)
3944                         goto out;
3945
3946                 perm = (isec->sclass == SECCLASS_TCP_SOCKET) ?
3947                        TCP_SOCKET__NAME_CONNECT : DCCP_SOCKET__NAME_CONNECT;
3948
3949                 AVC_AUDIT_DATA_INIT(&ad, NET);
3950                 ad.u.net.dport = htons(snum);
3951                 ad.u.net.family = sk->sk_family;
3952                 err = avc_has_perm(isec->sid, sid, isec->sclass, perm, &ad);
3953                 if (err)
3954                         goto out;
3955         }
3956
3957         err = selinux_netlbl_socket_connect(sk, address);
3958
3959 out:
3960         return err;
3961 }
3962
3963 static int selinux_socket_listen(struct socket *sock, int backlog)
3964 {
3965         return socket_has_perm(current, sock, SOCKET__LISTEN);
3966 }
3967
3968 static int selinux_socket_accept(struct socket *sock, struct socket *newsock)
3969 {
3970         int err;
3971         struct inode_security_struct *isec;
3972         struct inode_security_struct *newisec;
3973
3974         err = socket_has_perm(current, sock, SOCKET__ACCEPT);
3975         if (err)
3976                 return err;
3977
3978         newisec = SOCK_INODE(newsock)->i_security;
3979
3980         isec = SOCK_INODE(sock)->i_security;
3981         newisec->sclass = isec->sclass;
3982         newisec->sid = isec->sid;
3983         newisec->initialized = 1;
3984
3985         return 0;
3986 }
3987
3988 static int selinux_socket_sendmsg(struct socket *sock, struct msghdr *msg,
3989                                   int size)
3990 {
3991         int rc;
3992
3993         rc = socket_has_perm(current, sock, SOCKET__WRITE);
3994         if (rc)
3995                 return rc;
3996
3997         return selinux_netlbl_inode_permission(SOCK_INODE(sock), MAY_WRITE);
3998 }
3999
4000 static int selinux_socket_recvmsg(struct socket *sock, struct msghdr *msg,
4001                                   int size, int flags)
4002 {
4003         return socket_has_perm(current, sock, SOCKET__READ);
4004 }
4005
4006 static int selinux_socket_getsockname(struct socket *sock)
4007 {
4008         return socket_has_perm(current, sock, SOCKET__GETATTR);
4009 }
4010
4011 static int selinux_socket_getpeername(struct socket *sock)
4012 {
4013         return socket_has_perm(current, sock, SOCKET__GETATTR);
4014 }
4015
4016 static int selinux_socket_setsockopt(struct socket *sock, int level, int optname)
4017 {
4018         int err;
4019
4020         err = socket_has_perm(current, sock, SOCKET__SETOPT);
4021         if (err)
4022                 return err;
4023
4024         return selinux_netlbl_socket_setsockopt(sock, level, optname);
4025 }
4026
4027 static int selinux_socket_getsockopt(struct socket *sock, int level,
4028                                      int optname)
4029 {
4030         return socket_has_perm(current, sock, SOCKET__GETOPT);
4031 }
4032
4033 static int selinux_socket_shutdown(struct socket *sock, int how)
4034 {
4035         return socket_has_perm(current, sock, SOCKET__SHUTDOWN);
4036 }
4037
4038 static int selinux_socket_unix_stream_connect(struct socket *sock,
4039                                               struct socket *other,
4040                                               struct sock *newsk)
4041 {
4042         struct sk_security_struct *ssec;
4043         struct inode_security_struct *isec;
4044         struct inode_security_struct *other_isec;
4045         struct avc_audit_data ad;
4046         int err;
4047
4048         err = secondary_ops->unix_stream_connect(sock, other, newsk);
4049         if (err)
4050                 return err;
4051
4052         isec = SOCK_INODE(sock)->i_security;
4053         other_isec = SOCK_INODE(other)->i_security;
4054
4055         AVC_AUDIT_DATA_INIT(&ad, NET);
4056         ad.u.net.sk = other->sk;
4057
4058         err = avc_has_perm(isec->sid, other_isec->sid,
4059                            isec->sclass,
4060                            UNIX_STREAM_SOCKET__CONNECTTO, &ad);
4061         if (err)
4062                 return err;
4063
4064         /* connecting socket */
4065         ssec = sock->sk->sk_security;
4066         ssec->peer_sid = other_isec->sid;
4067
4068         /* server child socket */
4069         ssec = newsk->sk_security;
4070         ssec->peer_sid = isec->sid;
4071         err = security_sid_mls_copy(other_isec->sid, ssec->peer_sid, &ssec->sid);
4072
4073         return err;
4074 }
4075
4076 static int selinux_socket_unix_may_send(struct socket *sock,
4077                                         struct socket *other)
4078 {
4079         struct inode_security_struct *isec;
4080         struct inode_security_struct *other_isec;
4081         struct avc_audit_data ad;
4082         int err;
4083
4084         isec = SOCK_INODE(sock)->i_security;
4085         other_isec = SOCK_INODE(other)->i_security;
4086
4087         AVC_AUDIT_DATA_INIT(&ad, NET);
4088         ad.u.net.sk = other->sk;
4089
4090         err = avc_has_perm(isec->sid, other_isec->sid,
4091                            isec->sclass, SOCKET__SENDTO, &ad);
4092         if (err)
4093                 return err;
4094
4095         return 0;
4096 }
4097
4098 static int selinux_inet_sys_rcv_skb(int ifindex, char *addrp, u16 family,
4099                                     u32 peer_sid,
4100                                     struct avc_audit_data *ad)
4101 {
4102         int err;
4103         u32 if_sid;
4104         u32 node_sid;
4105
4106         err = sel_netif_sid(ifindex, &if_sid);
4107         if (err)
4108                 return err;
4109         err = avc_has_perm(peer_sid, if_sid,
4110                            SECCLASS_NETIF, NETIF__INGRESS, ad);
4111         if (err)
4112                 return err;
4113
4114         err = sel_netnode_sid(addrp, family, &node_sid);
4115         if (err)
4116                 return err;
4117         return avc_has_perm(peer_sid, node_sid,
4118                             SECCLASS_NODE, NODE__RECVFROM, ad);
4119 }
4120
4121 static int selinux_sock_rcv_skb_iptables_compat(struct sock *sk,
4122                                                 struct sk_buff *skb,
4123                                                 struct avc_audit_data *ad,
4124                                                 u16 family,
4125                                                 char *addrp)
4126 {
4127         int err;
4128         struct sk_security_struct *sksec = sk->sk_security;
4129         u16 sk_class;
4130         u32 netif_perm, node_perm, recv_perm;
4131         u32 port_sid, node_sid, if_sid, sk_sid;
4132
4133         sk_sid = sksec->sid;
4134         sk_class = sksec->sclass;
4135
4136         switch (sk_class) {
4137         case SECCLASS_UDP_SOCKET:
4138                 netif_perm = NETIF__UDP_RECV;
4139                 node_perm = NODE__UDP_RECV;
4140                 recv_perm = UDP_SOCKET__RECV_MSG;
4141                 break;
4142         case SECCLASS_TCP_SOCKET:
4143                 netif_perm = NETIF__TCP_RECV;
4144                 node_perm = NODE__TCP_RECV;
4145                 recv_perm = TCP_SOCKET__RECV_MSG;
4146                 break;
4147         case SECCLASS_DCCP_SOCKET:
4148                 netif_perm = NETIF__DCCP_RECV;
4149                 node_perm = NODE__DCCP_RECV;
4150                 recv_perm = DCCP_SOCKET__RECV_MSG;
4151                 break;
4152         default:
4153                 netif_perm = NETIF__RAWIP_RECV;
4154                 node_perm = NODE__RAWIP_RECV;
4155                 recv_perm = 0;
4156                 break;
4157         }
4158
4159         err = sel_netif_sid(skb->iif, &if_sid);
4160         if (err)
4161                 return err;
4162         err = avc_has_perm(sk_sid, if_sid, SECCLASS_NETIF, netif_perm, ad);
4163         if (err)
4164                 return err;
4165
4166         err = sel_netnode_sid(addrp, family, &node_sid);
4167         if (err)
4168                 return err;
4169         err = avc_has_perm(sk_sid, node_sid, SECCLASS_NODE, node_perm, ad);
4170         if (err)
4171                 return err;
4172
4173         if (!recv_perm)
4174                 return 0;
4175         err = sel_netport_sid(sk->sk_protocol,
4176                               ntohs(ad->u.net.sport), &port_sid);
4177         if (unlikely(err)) {
4178                 printk(KERN_WARNING
4179                        "SELinux: failure in"
4180                        " selinux_sock_rcv_skb_iptables_compat(),"
4181                        " network port label not found\n");
4182                 return err;
4183         }
4184         return avc_has_perm(sk_sid, port_sid, sk_class, recv_perm, ad);
4185 }
4186
4187 static int selinux_sock_rcv_skb_compat(struct sock *sk, struct sk_buff *skb,
4188                                        u16 family)
4189 {
4190         int err = 0;
4191         struct sk_security_struct *sksec = sk->sk_security;
4192         u32 peer_sid;
4193         u32 sk_sid = sksec->sid;
4194         struct avc_audit_data ad;
4195         char *addrp;
4196
4197         AVC_AUDIT_DATA_INIT(&ad, NET);
4198         ad.u.net.netif = skb->iif;
4199         ad.u.net.family = family;
4200         err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL);
4201         if (err)
4202                 return err;
4203
4204         if (selinux_compat_net)
4205                 err = selinux_sock_rcv_skb_iptables_compat(sk, skb, &ad,
4206                                                            family, addrp);
4207         else if (selinux_secmark_enabled())
4208                 err = avc_has_perm(sk_sid, skb->secmark, SECCLASS_PACKET,
4209                                    PACKET__RECV, &ad);
4210         if (err)
4211                 return err;
4212
4213         if (selinux_policycap_netpeer) {
4214                 err = selinux_skb_peerlbl_sid(skb, family, &peer_sid);
4215                 if (err)
4216                         return err;
4217                 err = avc_has_perm(sk_sid, peer_sid,
4218                                    SECCLASS_PEER, PEER__RECV, &ad);
4219                 if (err)
4220                         selinux_netlbl_err(skb, err, 0);
4221         } else {
4222                 err = selinux_netlbl_sock_rcv_skb(sksec, skb, family, &ad);
4223                 if (err)
4224                         return err;
4225                 err = selinux_xfrm_sock_rcv_skb(sksec->sid, skb, &ad);
4226         }
4227
4228         return err;
4229 }
4230
4231 static int selinux_socket_sock_rcv_skb(struct sock *sk, struct sk_buff *skb)
4232 {
4233         int err;
4234         struct sk_security_struct *sksec = sk->sk_security;
4235         u16 family = sk->sk_family;
4236         u32 sk_sid = sksec->sid;
4237         struct avc_audit_data ad;
4238         char *addrp;
4239         u8 secmark_active;
4240         u8 peerlbl_active;
4241
4242         if (family != PF_INET && family != PF_INET6)
4243                 return 0;
4244
4245         /* Handle mapped IPv4 packets arriving via IPv6 sockets */
4246         if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
4247                 family = PF_INET;
4248
4249         /* If any sort of compatibility mode is enabled then handoff processing
4250          * to the selinux_sock_rcv_skb_compat() function to deal with the
4251          * special handling.  We do this in an attempt to keep this function
4252          * as fast and as clean as possible. */
4253         if (selinux_compat_net || !selinux_policycap_netpeer)
4254                 return selinux_sock_rcv_skb_compat(sk, skb, family);
4255
4256         secmark_active = selinux_secmark_enabled();
4257         peerlbl_active = netlbl_enabled() || selinux_xfrm_enabled();
4258         if (!secmark_active && !peerlbl_active)
4259                 return 0;
4260
4261         AVC_AUDIT_DATA_INIT(&ad, NET);
4262         ad.u.net.netif = skb->iif;
4263         ad.u.net.family = family;
4264         err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL);
4265         if (err)
4266                 return err;
4267
4268         if (peerlbl_active) {
4269                 u32 peer_sid;
4270
4271                 err = selinux_skb_peerlbl_sid(skb, family, &peer_sid);
4272                 if (err)
4273                         return err;
4274                 err = selinux_inet_sys_rcv_skb(skb->iif, addrp, family,
4275                                                peer_sid, &ad);
4276                 if (err) {
4277                         selinux_netlbl_err(skb, err, 0);
4278                         return err;
4279                 }
4280                 err = avc_has_perm(sk_sid, peer_sid, SECCLASS_PEER,
4281                                    PEER__RECV, &ad);
4282                 if (err)
4283                         selinux_netlbl_err(skb, err, 0);
4284         }
4285
4286         if (secmark_active) {
4287                 err = avc_has_perm(sk_sid, skb->secmark, SECCLASS_PACKET,
4288                                    PACKET__RECV, &ad);
4289                 if (err)
4290                         return err;
4291         }
4292
4293         return err;
4294 }
4295
4296 static int selinux_socket_getpeersec_stream(struct socket *sock, char __user *optval,
4297                                             int __user *optlen, unsigned len)
4298 {
4299         int err = 0;
4300         char *scontext;
4301         u32 scontext_len;
4302         struct sk_security_struct *ssec;
4303         struct inode_security_struct *isec;
4304         u32 peer_sid = SECSID_NULL;
4305
4306         isec = SOCK_INODE(sock)->i_security;
4307
4308         if (isec->sclass == SECCLASS_UNIX_STREAM_SOCKET ||
4309             isec->sclass == SECCLASS_TCP_SOCKET) {
4310                 ssec = sock->sk->sk_security;
4311                 peer_sid = ssec->peer_sid;
4312         }
4313         if (peer_sid == SECSID_NULL) {
4314                 err = -ENOPROTOOPT;
4315                 goto out;
4316         }
4317
4318         err = security_sid_to_context(peer_sid, &scontext, &scontext_len);
4319
4320         if (err)
4321                 goto out;
4322
4323         if (scontext_len > len) {
4324                 err = -ERANGE;
4325                 goto out_len;
4326         }
4327
4328         if (copy_to_user(optval, scontext, scontext_len))
4329                 err = -EFAULT;
4330
4331 out_len:
4332         if (put_user(scontext_len, optlen))
4333                 err = -EFAULT;
4334
4335         kfree(scontext);
4336 out:
4337         return err;
4338 }
4339
4340 static int selinux_socket_getpeersec_dgram(struct socket *sock, struct sk_buff *skb, u32 *secid)
4341 {
4342         u32 peer_secid = SECSID_NULL;
4343         u16 family;
4344
4345         if (skb && skb->protocol == htons(ETH_P_IP))
4346                 family = PF_INET;
4347         else if (skb && skb->protocol == htons(ETH_P_IPV6))
4348                 family = PF_INET6;
4349         else if (sock)
4350                 family = sock->sk->sk_family;
4351         else
4352                 goto out;
4353
4354         if (sock && family == PF_UNIX)
4355                 selinux_inode_getsecid(SOCK_INODE(sock), &peer_secid);
4356         else if (skb)
4357                 selinux_skb_peerlbl_sid(skb, family, &peer_secid);
4358
4359 out:
4360         *secid = peer_secid;
4361         if (peer_secid == SECSID_NULL)
4362                 return -EINVAL;
4363         return 0;
4364 }
4365
4366 static int selinux_sk_alloc_security(struct sock *sk, int family, gfp_t priority)
4367 {
4368         return sk_alloc_security(sk, family, priority);
4369 }
4370
4371 static void selinux_sk_free_security(struct sock *sk)
4372 {
4373         sk_free_security(sk);
4374 }
4375
4376 static void selinux_sk_clone_security(const struct sock *sk, struct sock *newsk)
4377 {
4378         struct sk_security_struct *ssec = sk->sk_security;
4379         struct sk_security_struct *newssec = newsk->sk_security;
4380
4381         newssec->sid = ssec->sid;
4382         newssec->peer_sid = ssec->peer_sid;
4383         newssec->sclass = ssec->sclass;
4384
4385         selinux_netlbl_sk_security_reset(newssec, newsk->sk_family);
4386 }
4387
4388 static void selinux_sk_getsecid(struct sock *sk, u32 *secid)
4389 {
4390         if (!sk)
4391                 *secid = SECINITSID_ANY_SOCKET;
4392         else {
4393                 struct sk_security_struct *sksec = sk->sk_security;
4394
4395                 *secid = sksec->sid;
4396         }
4397 }
4398
4399 static void selinux_sock_graft(struct sock *sk, struct socket *parent)
4400 {
4401         struct inode_security_struct *isec = SOCK_INODE(parent)->i_security;
4402         struct sk_security_struct *sksec = sk->sk_security;
4403
4404         if (sk->sk_family == PF_INET || sk->sk_family == PF_INET6 ||
4405             sk->sk_family == PF_UNIX)
4406                 isec->sid = sksec->sid;
4407         sksec->sclass = isec->sclass;
4408 }
4409
4410 static int selinux_inet_conn_request(struct sock *sk, struct sk_buff *skb,
4411                                      struct request_sock *req)
4412 {
4413         struct sk_security_struct *sksec = sk->sk_security;
4414         int err;
4415         u16 family = sk->sk_family;
4416         u32 newsid;
4417         u32 peersid;
4418
4419         /* handle mapped IPv4 packets arriving via IPv6 sockets */
4420         if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
4421                 family = PF_INET;
4422
4423         err = selinux_skb_peerlbl_sid(skb, family, &peersid);
4424         if (err)
4425                 return err;
4426         if (peersid == SECSID_NULL) {
4427                 req->secid = sksec->sid;
4428                 req->peer_secid = SECSID_NULL;
4429                 return 0;
4430         }
4431
4432         err = security_sid_mls_copy(sksec->sid, peersid, &newsid);
4433         if (err)
4434                 return err;
4435
4436         req->secid = newsid;
4437         req->peer_secid = peersid;
4438         return 0;
4439 }
4440
4441 static void selinux_inet_csk_clone(struct sock *newsk,
4442                                    const struct request_sock *req)
4443 {
4444         struct sk_security_struct *newsksec = newsk->sk_security;
4445
4446         newsksec->sid = req->secid;
4447         newsksec->peer_sid = req->peer_secid;
4448         /* NOTE: Ideally, we should also get the isec->sid for the
4449            new socket in sync, but we don't have the isec available yet.
4450            So we will wait until sock_graft to do it, by which
4451            time it will have been created and available. */
4452
4453         /* We don't need to take any sort of lock here as we are the only
4454          * thread with access to newsksec */
4455         selinux_netlbl_sk_security_reset(newsksec, req->rsk_ops->family);
4456 }
4457
4458 static void selinux_inet_conn_established(struct sock *sk, struct sk_buff *skb)
4459 {
4460         u16 family = sk->sk_family;
4461         struct sk_security_struct *sksec = sk->sk_security;
4462
4463         /* handle mapped IPv4 packets arriving via IPv6 sockets */
4464         if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
4465                 family = PF_INET;
4466
4467         selinux_skb_peerlbl_sid(skb, family, &sksec->peer_sid);
4468
4469         selinux_netlbl_inet_conn_established(sk, family);
4470 }
4471
4472 static void selinux_req_classify_flow(const struct request_sock *req,
4473                                       struct flowi *fl)
4474 {
4475         fl->secid = req->secid;
4476 }
4477
4478 static int selinux_nlmsg_perm(struct sock *sk, struct sk_buff *skb)
4479 {
4480         int err = 0;
4481         u32 perm;
4482         struct nlmsghdr *nlh;
4483         struct socket *sock = sk->sk_socket;
4484         struct inode_security_struct *isec = SOCK_INODE(sock)->i_security;
4485
4486         if (skb->len < NLMSG_SPACE(0)) {
4487                 err = -EINVAL;
4488                 goto out;
4489         }
4490         nlh = nlmsg_hdr(skb);
4491
4492         err = selinux_nlmsg_lookup(isec->sclass, nlh->nlmsg_type, &perm);
4493         if (err) {
4494                 if (err == -EINVAL) {
4495                         audit_log(current->audit_context, GFP_KERNEL, AUDIT_SELINUX_ERR,
4496                                   "SELinux:  unrecognized netlink message"
4497                                   " type=%hu for sclass=%hu\n",
4498                                   nlh->nlmsg_type, isec->sclass);
4499                         if (!selinux_enforcing || security_get_allow_unknown())
4500                                 err = 0;
4501                 }
4502
4503                 /* Ignore */
4504                 if (err == -ENOENT)
4505                         err = 0;
4506                 goto out;
4507         }
4508
4509         err = socket_has_perm(current, sock, perm);
4510 out:
4511         return err;
4512 }
4513
4514 #ifdef CONFIG_NETFILTER
4515
4516 static unsigned int selinux_ip_forward(struct sk_buff *skb, int ifindex,
4517                                        u16 family)
4518 {
4519         int err;
4520         char *addrp;
4521         u32 peer_sid;
4522         struct avc_audit_data ad;
4523         u8 secmark_active;
4524         u8 netlbl_active;
4525         u8 peerlbl_active;
4526
4527         if (!selinux_policycap_netpeer)
4528                 return NF_ACCEPT;
4529
4530         secmark_active = selinux_secmark_enabled();
4531         netlbl_active = netlbl_enabled();
4532         peerlbl_active = netlbl_active || selinux_xfrm_enabled();
4533         if (!secmark_active && !peerlbl_active)
4534                 return NF_ACCEPT;
4535
4536         if (selinux_skb_peerlbl_sid(skb, family, &peer_sid) != 0)
4537                 return NF_DROP;
4538
4539         AVC_AUDIT_DATA_INIT(&ad, NET);
4540         ad.u.net.netif = ifindex;
4541         ad.u.net.family = family;
4542         if (selinux_parse_skb(skb, &ad, &addrp, 1, NULL) != 0)
4543                 return NF_DROP;
4544
4545         if (peerlbl_active) {
4546                 err = selinux_inet_sys_rcv_skb(ifindex, addrp, family,
4547                                                peer_sid, &ad);
4548                 if (err) {
4549                         selinux_netlbl_err(skb, err, 1);
4550                         return NF_DROP;
4551                 }
4552         }
4553
4554         if (secmark_active)
4555                 if (avc_has_perm(peer_sid, skb->secmark,
4556                                  SECCLASS_PACKET, PACKET__FORWARD_IN, &ad))
4557                         return NF_DROP;
4558
4559         if (netlbl_active)
4560                 /* we do this in the FORWARD path and not the POST_ROUTING
4561                  * path because we want to make sure we apply the necessary
4562                  * labeling before IPsec is applied so we can leverage AH
4563                  * protection */
4564                 if (selinux_netlbl_skbuff_setsid(skb, family, peer_sid) != 0)
4565                         return NF_DROP;
4566
4567         return NF_ACCEPT;
4568 }
4569
4570 static unsigned int selinux_ipv4_forward(unsigned int hooknum,
4571                                          struct sk_buff *skb,
4572                                          const struct net_device *in,
4573                                          const struct net_device *out,
4574                                          int (*okfn)(struct sk_buff *))
4575 {
4576         return selinux_ip_forward(skb, in->ifindex, PF_INET);
4577 }
4578
4579 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
4580 static unsigned int selinux_ipv6_forward(unsigned int hooknum,
4581                                          struct sk_buff *skb,
4582                                          const struct net_device *in,
4583                                          const struct net_device *out,
4584                                          int (*okfn)(struct sk_buff *))
4585 {
4586         return selinux_ip_forward(skb, in->ifindex, PF_INET6);
4587 }
4588 #endif  /* IPV6 */
4589
4590 static unsigned int selinux_ip_output(struct sk_buff *skb,
4591                                       u16 family)
4592 {
4593         u32 sid;
4594
4595         if (!netlbl_enabled())
4596                 return NF_ACCEPT;
4597
4598         /* we do this in the LOCAL_OUT path and not the POST_ROUTING path
4599          * because we want to make sure we apply the necessary labeling
4600          * before IPsec is applied so we can leverage AH protection */
4601         if (skb->sk) {
4602                 struct sk_security_struct *sksec = skb->sk->sk_security;
4603                 sid = sksec->sid;
4604         } else
4605                 sid = SECINITSID_KERNEL;
4606         if (selinux_netlbl_skbuff_setsid(skb, family, sid) != 0)
4607                 return NF_DROP;
4608
4609         return NF_ACCEPT;
4610 }
4611
4612 static unsigned int selinux_ipv4_output(unsigned int hooknum,
4613                                         struct sk_buff *skb,
4614                                         const struct net_device *in,
4615                                         const struct net_device *out,
4616                                         int (*okfn)(struct sk_buff *))
4617 {
4618         return selinux_ip_output(skb, PF_INET);
4619 }
4620
4621 static int selinux_ip_postroute_iptables_compat(struct sock *sk,
4622                                                 int ifindex,
4623                                                 struct avc_audit_data *ad,
4624                                                 u16 family, char *addrp)
4625 {
4626         int err;
4627         struct sk_security_struct *sksec = sk->sk_security;
4628         u16 sk_class;
4629         u32 netif_perm, node_perm, send_perm;
4630         u32 port_sid, node_sid, if_sid, sk_sid;
4631
4632         sk_sid = sksec->sid;
4633         sk_class = sksec->sclass;
4634
4635         switch (sk_class) {
4636         case SECCLASS_UDP_SOCKET:
4637                 netif_perm = NETIF__UDP_SEND;
4638                 node_perm = NODE__UDP_SEND;
4639                 send_perm = UDP_SOCKET__SEND_MSG;
4640                 break;
4641         case SECCLASS_TCP_SOCKET:
4642                 netif_perm = NETIF__TCP_SEND;
4643                 node_perm = NODE__TCP_SEND;
4644                 send_perm = TCP_SOCKET__SEND_MSG;
4645                 break;
4646         case SECCLASS_DCCP_SOCKET:
4647                 netif_perm = NETIF__DCCP_SEND;
4648                 node_perm = NODE__DCCP_SEND;
4649                 send_perm = DCCP_SOCKET__SEND_MSG;
4650                 break;
4651         default:
4652                 netif_perm = NETIF__RAWIP_SEND;
4653                 node_perm = NODE__RAWIP_SEND;
4654                 send_perm = 0;
4655                 break;
4656         }
4657
4658         err = sel_netif_sid(ifindex, &if_sid);
4659         if (err)
4660                 return err;
4661         err = avc_has_perm(sk_sid, if_sid, SECCLASS_NETIF, netif_perm, ad);
4662                 return err;
4663
4664         err = sel_netnode_sid(addrp, family, &node_sid);
4665         if (err)
4666                 return err;
4667         err = avc_has_perm(sk_sid, node_sid, SECCLASS_NODE, node_perm, ad);
4668         if (err)
4669                 return err;
4670
4671         if (send_perm != 0)
4672                 return 0;
4673
4674         err = sel_netport_sid(sk->sk_protocol,
4675                               ntohs(ad->u.net.dport), &port_sid);
4676         if (unlikely(err)) {
4677                 printk(KERN_WARNING
4678                        "SELinux: failure in"
4679                        " selinux_ip_postroute_iptables_compat(),"
4680                        " network port label not found\n");
4681                 return err;
4682         }
4683         return avc_has_perm(sk_sid, port_sid, sk_class, send_perm, ad);
4684 }
4685
4686 static unsigned int selinux_ip_postroute_compat(struct sk_buff *skb,
4687                                                 int ifindex,
4688                                                 u16 family)
4689 {
4690         struct sock *sk = skb->sk;
4691         struct sk_security_struct *sksec;
4692         struct avc_audit_data ad;
4693         char *addrp;
4694         u8 proto;
4695
4696         if (sk == NULL)
4697                 return NF_ACCEPT;
4698         sksec = sk->sk_security;
4699
4700         AVC_AUDIT_DATA_INIT(&ad, NET);
4701         ad.u.net.netif = ifindex;
4702         ad.u.net.family = family;
4703         if (selinux_parse_skb(skb, &ad, &addrp, 0, &proto))
4704                 return NF_DROP;
4705
4706         if (selinux_compat_net) {
4707                 if (selinux_ip_postroute_iptables_compat(skb->sk, ifindex,
4708                                                          &ad, family, addrp))
4709                         return NF_DROP;
4710         } else if (selinux_secmark_enabled()) {
4711                 if (avc_has_perm(sksec->sid, skb->secmark,
4712                                  SECCLASS_PACKET, PACKET__SEND, &ad))
4713                         return NF_DROP;
4714         }
4715
4716         if (selinux_policycap_netpeer)
4717                 if (selinux_xfrm_postroute_last(sksec->sid, skb, &ad, proto))
4718                         return NF_DROP;
4719
4720         return NF_ACCEPT;
4721 }
4722
4723 static unsigned int selinux_ip_postroute(struct sk_buff *skb, int ifindex,
4724                                          u16 family)
4725 {
4726         u32 secmark_perm;
4727         u32 peer_sid;
4728         struct sock *sk;
4729         struct avc_audit_data ad;
4730         char *addrp;
4731         u8 secmark_active;
4732         u8 peerlbl_active;
4733
4734         /* If any sort of compatibility mode is enabled then handoff processing
4735          * to the selinux_ip_postroute_compat() function to deal with the
4736          * special handling.  We do this in an attempt to keep this function
4737          * as fast and as clean as possible. */
4738         if (selinux_compat_net || !selinux_policycap_netpeer)
4739                 return selinux_ip_postroute_compat(skb, ifindex, family);
4740 #ifdef CONFIG_XFRM
4741         /* If skb->dst->xfrm is non-NULL then the packet is undergoing an IPsec
4742          * packet transformation so allow the packet to pass without any checks
4743          * since we'll have another chance to perform access control checks
4744          * when the packet is on it's final way out.
4745          * NOTE: there appear to be some IPv6 multicast cases where skb->dst
4746          *       is NULL, in this case go ahead and apply access control. */
4747         if (skb->dst != NULL && skb->dst->xfrm != NULL)
4748                 return NF_ACCEPT;
4749 #endif
4750         secmark_active = selinux_secmark_enabled();
4751         peerlbl_active = netlbl_enabled() || selinux_xfrm_enabled();
4752         if (!secmark_active && !peerlbl_active)
4753                 return NF_ACCEPT;
4754
4755         /* if the packet is being forwarded then get the peer label from the
4756          * packet itself; otherwise check to see if it is from a local
4757          * application or the kernel, if from an application get the peer label
4758          * from the sending socket, otherwise use the kernel's sid */
4759         sk = skb->sk;
4760         if (sk == NULL) {
4761                 switch (family) {
4762                 case PF_INET:
4763                         if (IPCB(skb)->flags & IPSKB_FORWARDED)
4764                                 secmark_perm = PACKET__FORWARD_OUT;
4765                         else
4766                                 secmark_perm = PACKET__SEND;
4767                         break;
4768                 case PF_INET6:
4769                         if (IP6CB(skb)->flags & IP6SKB_FORWARDED)
4770                                 secmark_perm = PACKET__FORWARD_OUT;
4771                         else
4772                                 secmark_perm = PACKET__SEND;
4773                         break;
4774                 default:
4775                         return NF_DROP;
4776                 }
4777                 if (secmark_perm == PACKET__FORWARD_OUT) {
4778                         if (selinux_skb_peerlbl_sid(skb, family, &peer_sid))
4779                                 return NF_DROP;
4780                 } else
4781                         peer_sid = SECINITSID_KERNEL;
4782         } else {
4783                 struct sk_security_struct *sksec = sk->sk_security;
4784                 peer_sid = sksec->sid;
4785                 secmark_perm = PACKET__SEND;
4786         }
4787
4788         AVC_AUDIT_DATA_INIT(&ad, NET);
4789         ad.u.net.netif = ifindex;
4790         ad.u.net.family = family;
4791         if (selinux_parse_skb(skb, &ad, &addrp, 0, NULL))
4792                 return NF_DROP;
4793
4794         if (secmark_active)
4795                 if (avc_has_perm(peer_sid, skb->secmark,
4796                                  SECCLASS_PACKET, secmark_perm, &ad))
4797                         return NF_DROP;
4798
4799         if (peerlbl_active) {
4800                 u32 if_sid;
4801                 u32 node_sid;
4802
4803                 if (sel_netif_sid(ifindex, &if_sid))
4804                         return NF_DROP;
4805                 if (avc_has_perm(peer_sid, if_sid,
4806                                  SECCLASS_NETIF, NETIF__EGRESS, &ad))
4807                         return NF_DROP;
4808
4809                 if (sel_netnode_sid(addrp, family, &node_sid))
4810                         return NF_DROP;
4811                 if (avc_has_perm(peer_sid, node_sid,
4812                                  SECCLASS_NODE, NODE__SENDTO, &ad))
4813                         return NF_DROP;
4814         }
4815
4816         return NF_ACCEPT;
4817 }
4818
4819 static unsigned int selinux_ipv4_postroute(unsigned int hooknum,
4820                                            struct sk_buff *skb,
4821                                            const struct net_device *in,
4822                                            const struct net_device *out,
4823                                            int (*okfn)(struct sk_buff *))
4824 {
4825         return selinux_ip_postroute(skb, out->ifindex, PF_INET);
4826 }
4827
4828 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
4829 static unsigned int selinux_ipv6_postroute(unsigned int hooknum,
4830                                            struct sk_buff *skb,
4831                                            const struct net_device *in,
4832                                            const struct net_device *out,
4833                                            int (*okfn)(struct sk_buff *))
4834 {
4835         return selinux_ip_postroute(skb, out->ifindex, PF_INET6);
4836 }
4837 #endif  /* IPV6 */
4838
4839 #endif  /* CONFIG_NETFILTER */
4840
4841 static int selinux_netlink_send(struct sock *sk, struct sk_buff *skb)
4842 {
4843         int err;
4844
4845         err = secondary_ops->netlink_send(sk, skb);
4846         if (err)
4847                 return err;
4848
4849         if (policydb_loaded_version >= POLICYDB_VERSION_NLCLASS)
4850                 err = selinux_nlmsg_perm(sk, skb);
4851
4852         return err;
4853 }
4854
4855 static int selinux_netlink_recv(struct sk_buff *skb, int capability)
4856 {
4857         int err;
4858         struct avc_audit_data ad;
4859
4860         err = secondary_ops->netlink_recv(skb, capability);
4861         if (err)
4862                 return err;
4863
4864         AVC_AUDIT_DATA_INIT(&ad, CAP);
4865         ad.u.cap = capability;
4866
4867         return avc_has_perm(NETLINK_CB(skb).sid, NETLINK_CB(skb).sid,
4868                             SECCLASS_CAPABILITY, CAP_TO_MASK(capability), &ad);
4869 }
4870
4871 static int ipc_alloc_security(struct task_struct *task,
4872                               struct kern_ipc_perm *perm,
4873                               u16 sclass)
4874 {
4875         struct ipc_security_struct *isec;
4876         u32 sid;
4877
4878         isec = kzalloc(sizeof(struct ipc_security_struct), GFP_KERNEL);
4879         if (!isec)
4880                 return -ENOMEM;
4881
4882         sid = task_sid(task);
4883         isec->sclass = sclass;
4884         isec->sid = sid;
4885         perm->security = isec;
4886
4887         return 0;
4888 }
4889
4890 static void ipc_free_security(struct kern_ipc_perm *perm)
4891 {
4892         struct ipc_security_struct *isec = perm->security;
4893         perm->security = NULL;
4894         kfree(isec);
4895 }
4896
4897 static int msg_msg_alloc_security(struct msg_msg *msg)
4898 {
4899         struct msg_security_struct *msec;
4900
4901         msec = kzalloc(sizeof(struct msg_security_struct), GFP_KERNEL);
4902         if (!msec)
4903                 return -ENOMEM;
4904
4905         msec->sid = SECINITSID_UNLABELED;
4906         msg->security = msec;
4907
4908         return 0;
4909 }
4910
4911 static void msg_msg_free_security(struct msg_msg *msg)
4912 {
4913         struct msg_security_struct *msec = msg->security;
4914
4915         msg->security = NULL;
4916         kfree(msec);
4917 }
4918
4919 static int ipc_has_perm(struct kern_ipc_perm *ipc_perms,
4920                         u32 perms)
4921 {
4922         struct ipc_security_struct *isec;
4923         struct avc_audit_data ad;
4924         u32 sid = current_sid();
4925
4926         isec = ipc_perms->security;
4927
4928         AVC_AUDIT_DATA_INIT(&ad, IPC);
4929         ad.u.ipc_id = ipc_perms->key;
4930
4931         return avc_has_perm(sid, isec->sid, isec->sclass, perms, &ad);
4932 }
4933
4934 static int selinux_msg_msg_alloc_security(struct msg_msg *msg)
4935 {
4936         return msg_msg_alloc_security(msg);
4937 }
4938
4939 static void selinux_msg_msg_free_security(struct msg_msg *msg)
4940 {
4941         msg_msg_free_security(msg);
4942 }
4943
4944 /* message queue security operations */
4945 static int selinux_msg_queue_alloc_security(struct msg_queue *msq)
4946 {
4947         struct ipc_security_struct *isec;
4948         struct avc_audit_data ad;
4949         u32 sid = current_sid();
4950         int rc;
4951
4952         rc = ipc_alloc_security(current, &msq->q_perm, SECCLASS_MSGQ);
4953         if (rc)
4954                 return rc;
4955
4956         isec = msq->q_perm.security;
4957
4958         AVC_AUDIT_DATA_INIT(&ad, IPC);
4959         ad.u.ipc_id = msq->q_perm.key;
4960
4961         rc = avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
4962                           MSGQ__CREATE, &ad);
4963         if (rc) {
4964                 ipc_free_security(&msq->q_perm);
4965                 return rc;
4966         }
4967         return 0;
4968 }
4969
4970 static void selinux_msg_queue_free_security(struct msg_queue *msq)
4971 {
4972         ipc_free_security(&msq->q_perm);
4973 }
4974
4975 static int selinux_msg_queue_associate(struct msg_queue *msq, int msqflg)
4976 {
4977         struct ipc_security_struct *isec;
4978         struct avc_audit_data ad;
4979         u32 sid = current_sid();
4980
4981         isec = msq->q_perm.security;
4982
4983         AVC_AUDIT_DATA_INIT(&ad, IPC);
4984         ad.u.ipc_id = msq->q_perm.key;
4985
4986         return avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
4987                             MSGQ__ASSOCIATE, &ad);
4988 }
4989
4990 static int selinux_msg_queue_msgctl(struct msg_queue *msq, int cmd)
4991 {
4992         int err;
4993         int perms;
4994
4995         switch (cmd) {
4996         case IPC_INFO:
4997         case MSG_INFO:
4998                 /* No specific object, just general system-wide information. */
4999                 return task_has_system(current, SYSTEM__IPC_INFO);
5000         case IPC_STAT:
5001         case MSG_STAT:
5002                 perms = MSGQ__GETATTR | MSGQ__ASSOCIATE;
5003                 break;
5004         case IPC_SET:
5005                 perms = MSGQ__SETATTR;
5006                 break;
5007         case IPC_RMID:
5008                 perms = MSGQ__DESTROY;
5009                 break;
5010         default:
5011                 return 0;
5012         }
5013
5014         err = ipc_has_perm(&msq->q_perm, perms);
5015         return err;
5016 }
5017
5018 static int selinux_msg_queue_msgsnd(struct msg_queue *msq, struct msg_msg *msg, int msqflg)
5019 {
5020         struct ipc_security_struct *isec;
5021         struct msg_security_struct *msec;
5022         struct avc_audit_data ad;
5023         u32 sid = current_sid();
5024         int rc;
5025
5026         isec = msq->q_perm.security;
5027         msec = msg->security;
5028
5029         /*
5030          * First time through, need to assign label to the message
5031          */
5032         if (msec->sid == SECINITSID_UNLABELED) {
5033                 /*
5034                  * Compute new sid based on current process and
5035                  * message queue this message will be stored in
5036                  */
5037                 rc = security_transition_sid(sid, isec->sid, SECCLASS_MSG,
5038                                              &msec->sid);
5039                 if (rc)
5040                         return rc;
5041         }
5042
5043         AVC_AUDIT_DATA_INIT(&ad, IPC);
5044         ad.u.ipc_id = msq->q_perm.key;
5045
5046         /* Can this process write to the queue? */
5047         rc = avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
5048                           MSGQ__WRITE, &ad);
5049         if (!rc)
5050                 /* Can this process send the message */
5051                 rc = avc_has_perm(sid, msec->sid, SECCLASS_MSG,
5052                                   MSG__SEND, &ad);
5053         if (!rc)
5054                 /* Can the message be put in the queue? */
5055                 rc = avc_has_perm(msec->sid, isec->sid, SECCLASS_MSGQ,
5056                                   MSGQ__ENQUEUE, &ad);
5057
5058         return rc;
5059 }
5060
5061 static int selinux_msg_queue_msgrcv(struct msg_queue *msq, struct msg_msg *msg,
5062                                     struct task_struct *target,
5063                                     long type, int mode)
5064 {
5065         struct ipc_security_struct *isec;
5066         struct msg_security_struct *msec;
5067         struct avc_audit_data ad;
5068         u32 sid = task_sid(target);
5069         int rc;
5070
5071         isec = msq->q_perm.security;
5072         msec = msg->security;
5073
5074         AVC_AUDIT_DATA_INIT(&ad, IPC);
5075         ad.u.ipc_id = msq->q_perm.key;
5076
5077         rc = avc_has_perm(sid, isec->sid,
5078                           SECCLASS_MSGQ, MSGQ__READ, &ad);
5079         if (!rc)
5080                 rc = avc_has_perm(sid, msec->sid,
5081                                   SECCLASS_MSG, MSG__RECEIVE, &ad);
5082         return rc;
5083 }
5084
5085 /* Shared Memory security operations */
5086 static int selinux_shm_alloc_security(struct shmid_kernel *shp)
5087 {
5088         struct ipc_security_struct *isec;
5089         struct avc_audit_data ad;
5090         u32 sid = current_sid();
5091         int rc;
5092
5093         rc = ipc_alloc_security(current, &shp->shm_perm, SECCLASS_SHM);
5094         if (rc)
5095                 return rc;
5096
5097         isec = shp->shm_perm.security;
5098
5099         AVC_AUDIT_DATA_INIT(&ad, IPC);
5100         ad.u.ipc_id = shp->shm_perm.key;
5101
5102         rc = avc_has_perm(sid, isec->sid, SECCLASS_SHM,
5103                           SHM__CREATE, &ad);
5104         if (rc) {
5105                 ipc_free_security(&shp->shm_perm);
5106                 return rc;
5107         }
5108         return 0;
5109 }
5110
5111 static void selinux_shm_free_security(struct shmid_kernel *shp)
5112 {
5113         ipc_free_security(&shp->shm_perm);
5114 }
5115
5116 static int selinux_shm_associate(struct shmid_kernel *shp, int shmflg)
5117 {
5118         struct ipc_security_struct *isec;
5119         struct avc_audit_data ad;
5120         u32 sid = current_sid();
5121
5122         isec = shp->shm_perm.security;
5123
5124         AVC_AUDIT_DATA_INIT(&ad, IPC);
5125         ad.u.ipc_id = shp->shm_perm.key;
5126
5127         return avc_has_perm(sid, isec->sid, SECCLASS_SHM,
5128                             SHM__ASSOCIATE, &ad);
5129 }
5130
5131 /* Note, at this point, shp is locked down */
5132 static int selinux_shm_shmctl(struct shmid_kernel *shp, int cmd)
5133 {
5134         int perms;
5135         int err;
5136
5137         switch (cmd) {
5138         case IPC_INFO:
5139         case SHM_INFO:
5140                 /* No specific object, just general system-wide information. */
5141                 return task_has_system(current, SYSTEM__IPC_INFO);
5142         case IPC_STAT:
5143         case SHM_STAT:
5144                 perms = SHM__GETATTR | SHM__ASSOCIATE;
5145                 break;
5146         case IPC_SET:
5147                 perms = SHM__SETATTR;
5148                 break;
5149         case SHM_LOCK:
5150         case SHM_UNLOCK:
5151                 perms = SHM__LOCK;
5152                 break;
5153         case IPC_RMID:
5154                 perms = SHM__DESTROY;
5155                 break;
5156         default:
5157                 return 0;
5158         }
5159
5160         err = ipc_has_perm(&shp->shm_perm, perms);
5161         return err;
5162 }
5163
5164 static int selinux_shm_shmat(struct shmid_kernel *shp,
5165                              char __user *shmaddr, int shmflg)
5166 {
5167         u32 perms;
5168         int rc;
5169
5170         rc = secondary_ops->shm_shmat(shp, shmaddr, shmflg);
5171         if (rc)
5172                 return rc;
5173
5174         if (shmflg & SHM_RDONLY)
5175                 perms = SHM__READ;
5176         else
5177                 perms = SHM__READ | SHM__WRITE;
5178
5179         return ipc_has_perm(&shp->shm_perm, perms);
5180 }
5181
5182 /* Semaphore security operations */
5183 static int selinux_sem_alloc_security(struct sem_array *sma)
5184 {
5185         struct ipc_security_struct *isec;
5186         struct avc_audit_data ad;
5187         u32 sid = current_sid();
5188         int rc;
5189
5190         rc = ipc_alloc_security(current, &sma->sem_perm, SECCLASS_SEM);
5191         if (rc)
5192                 return rc;
5193
5194         isec = sma->sem_perm.security;
5195
5196         AVC_AUDIT_DATA_INIT(&ad, IPC);
5197         ad.u.ipc_id = sma->sem_perm.key;
5198
5199         rc = avc_has_perm(sid, isec->sid, SECCLASS_SEM,
5200                           SEM__CREATE, &ad);
5201         if (rc) {
5202                 ipc_free_security(&sma->sem_perm);
5203                 return rc;
5204         }
5205         return 0;
5206 }
5207
5208 static void selinux_sem_free_security(struct sem_array *sma)
5209 {
5210         ipc_free_security(&sma->sem_perm);
5211 }
5212
5213 static int selinux_sem_associate(struct sem_array *sma, int semflg)
5214 {
5215         struct ipc_security_struct *isec;
5216         struct avc_audit_data ad;
5217         u32 sid = current_sid();
5218
5219         isec = sma->sem_perm.security;
5220
5221         AVC_AUDIT_DATA_INIT(&ad, IPC);
5222         ad.u.ipc_id = sma->sem_perm.key;
5223
5224         return avc_has_perm(sid, isec->sid, SECCLASS_SEM,
5225                             SEM__ASSOCIATE, &ad);
5226 }
5227
5228 /* Note, at this point, sma is locked down */
5229 static int selinux_sem_semctl(struct sem_array *sma, int cmd)
5230 {
5231         int err;
5232         u32 perms;
5233
5234         switch (cmd) {
5235         case IPC_INFO:
5236         case SEM_INFO:
5237                 /* No specific object, just general system-wide information. */
5238                 return task_has_system(current, SYSTEM__IPC_INFO);
5239         case GETPID:
5240         case GETNCNT:
5241         case GETZCNT:
5242                 perms = SEM__GETATTR;
5243                 break;
5244         case GETVAL:
5245         case GETALL:
5246                 perms = SEM__READ;
5247                 break;
5248         case SETVAL:
5249         case SETALL:
5250                 perms = SEM__WRITE;
5251                 break;
5252         case IPC_RMID:
5253                 perms = SEM__DESTROY;
5254                 break;
5255         case IPC_SET:
5256                 perms = SEM__SETATTR;
5257                 break;
5258         case IPC_STAT:
5259         case SEM_STAT:
5260                 perms = SEM__GETATTR | SEM__ASSOCIATE;
5261                 break;
5262         default:
5263                 return 0;
5264         }
5265
5266         err = ipc_has_perm(&sma->sem_perm, perms);
5267         return err;
5268 }
5269
5270 static int selinux_sem_semop(struct sem_array *sma,
5271                              struct sembuf *sops, unsigned nsops, int alter)
5272 {
5273         u32 perms;
5274
5275         if (alter)
5276                 perms = SEM__READ | SEM__WRITE;
5277         else
5278                 perms = SEM__READ;
5279
5280         return ipc_has_perm(&sma->sem_perm, perms);
5281 }
5282
5283 static int selinux_ipc_permission(struct kern_ipc_perm *ipcp, short flag)
5284 {
5285         u32 av = 0;
5286
5287         av = 0;
5288         if (flag & S_IRUGO)
5289                 av |= IPC__UNIX_READ;
5290         if (flag & S_IWUGO)
5291                 av |= IPC__UNIX_WRITE;
5292
5293         if (av == 0)
5294                 return 0;
5295
5296         return ipc_has_perm(ipcp, av);
5297 }
5298
5299 static void selinux_ipc_getsecid(struct kern_ipc_perm *ipcp, u32 *secid)
5300 {
5301         struct ipc_security_struct *isec = ipcp->security;
5302         *secid = isec->sid;
5303 }
5304
5305 static void selinux_d_instantiate(struct dentry *dentry, struct inode *inode)
5306 {
5307         if (inode)
5308                 inode_doinit_with_dentry(inode, dentry);
5309 }
5310
5311 static int selinux_getprocattr(struct task_struct *p,
5312                                char *name, char **value)
5313 {
5314         const struct task_security_struct *__tsec;
5315         u32 sid;
5316         int error;
5317         unsigned len;
5318
5319         if (current != p) {
5320                 error = current_has_perm(p, PROCESS__GETATTR);
5321                 if (error)
5322                         return error;
5323         }
5324
5325         rcu_read_lock();
5326         __tsec = __task_cred(p)->security;
5327
5328         if (!strcmp(name, "current"))
5329                 sid = __tsec->sid;
5330         else if (!strcmp(name, "prev"))
5331                 sid = __tsec->osid;
5332         else if (!strcmp(name, "exec"))
5333                 sid = __tsec->exec_sid;
5334         else if (!strcmp(name, "fscreate"))
5335                 sid = __tsec->create_sid;
5336         else if (!strcmp(name, "keycreate"))
5337                 sid = __tsec->keycreate_sid;
5338         else if (!strcmp(name, "sockcreate"))
5339                 sid = __tsec->sockcreate_sid;
5340         else
5341                 goto invalid;
5342         rcu_read_unlock();
5343
5344         if (!sid)
5345                 return 0;
5346
5347         error = security_sid_to_context(sid, value, &len);
5348         if (error)
5349                 return error;
5350         return len;
5351
5352 invalid:
5353         rcu_read_unlock();
5354         return -EINVAL;
5355 }
5356
5357 static int selinux_setprocattr(struct task_struct *p,
5358                                char *name, void *value, size_t size)
5359 {
5360         struct task_security_struct *tsec;
5361         struct task_struct *tracer;
5362         struct cred *new;
5363         u32 sid = 0, ptsid;
5364         int error;
5365         char *str = value;
5366
5367         if (current != p) {
5368                 /* SELinux only allows a process to change its own
5369                    security attributes. */
5370                 return -EACCES;
5371         }
5372
5373         /*
5374          * Basic control over ability to set these attributes at all.
5375          * current == p, but we'll pass them separately in case the
5376          * above restriction is ever removed.
5377          */
5378         if (!strcmp(name, "exec"))
5379                 error = current_has_perm(p, PROCESS__SETEXEC);
5380         else if (!strcmp(name, "fscreate"))
5381                 error = current_has_perm(p, PROCESS__SETFSCREATE);
5382         else if (!strcmp(name, "keycreate"))
5383                 error = current_has_perm(p, PROCESS__SETKEYCREATE);
5384         else if (!strcmp(name, "sockcreate"))
5385                 error = current_has_perm(p, PROCESS__SETSOCKCREATE);
5386         else if (!strcmp(name, "current"))
5387                 error = current_has_perm(p, PROCESS__SETCURRENT);
5388         else
5389                 error = -EINVAL;
5390         if (error)
5391                 return error;
5392
5393         /* Obtain a SID for the context, if one was specified. */
5394         if (size && str[1] && str[1] != '\n') {
5395                 if (str[size-1] == '\n') {
5396                         str[size-1] = 0;
5397                         size--;
5398                 }
5399                 error = security_context_to_sid(value, size, &sid);
5400                 if (error == -EINVAL && !strcmp(name, "fscreate")) {
5401                         if (!capable(CAP_MAC_ADMIN))
5402                                 return error;
5403                         error = security_context_to_sid_force(value, size,
5404                                                               &sid);
5405                 }
5406                 if (error)
5407                         return error;
5408         }
5409
5410         new = prepare_creds();
5411         if (!new)
5412                 return -ENOMEM;
5413
5414         /* Permission checking based on the specified context is
5415            performed during the actual operation (execve,
5416            open/mkdir/...), when we know the full context of the
5417            operation.  See selinux_bprm_set_creds for the execve
5418            checks and may_create for the file creation checks. The
5419            operation will then fail if the context is not permitted. */
5420         tsec = new->security;
5421         if (!strcmp(name, "exec")) {
5422                 tsec->exec_sid = sid;
5423         } else if (!strcmp(name, "fscreate")) {
5424                 tsec->create_sid = sid;
5425         } else if (!strcmp(name, "keycreate")) {
5426                 error = may_create_key(sid, p);
5427                 if (error)
5428                         goto abort_change;
5429                 tsec->keycreate_sid = sid;
5430         } else if (!strcmp(name, "sockcreate")) {
5431                 tsec->sockcreate_sid = sid;
5432         } else if (!strcmp(name, "current")) {
5433                 error = -EINVAL;
5434                 if (sid == 0)
5435                         goto abort_change;
5436
5437                 /* Only allow single threaded processes to change context */
5438                 error = -EPERM;
5439                 if (!is_single_threaded(p)) {
5440                         error = security_bounded_transition(tsec->sid, sid);
5441                         if (error)
5442                                 goto abort_change;
5443                 }
5444
5445                 /* Check permissions for the transition. */
5446                 error = avc_has_perm(tsec->sid, sid, SECCLASS_PROCESS,
5447                                      PROCESS__DYNTRANSITION, NULL);
5448                 if (error)
5449                         goto abort_change;
5450
5451                 /* Check for ptracing, and update the task SID if ok.
5452                    Otherwise, leave SID unchanged and fail. */
5453                 ptsid = 0;
5454                 task_lock(p);
5455                 tracer = tracehook_tracer_task(p);
5456                 if (tracer)
5457                         ptsid = task_sid(tracer);
5458                 task_unlock(p);
5459
5460                 if (tracer) {
5461                         error = avc_has_perm(ptsid, sid, SECCLASS_PROCESS,
5462                                              PROCESS__PTRACE, NULL);
5463                         if (error)
5464                                 goto abort_change;
5465                 }
5466
5467                 tsec->sid = sid;
5468         } else {
5469                 error = -EINVAL;
5470                 goto abort_change;
5471         }
5472
5473         commit_creds(new);
5474         return size;
5475
5476 abort_change:
5477         abort_creds(new);
5478         return error;
5479 }
5480
5481 static int selinux_secid_to_secctx(u32 secid, char **secdata, u32 *seclen)
5482 {
5483         return security_sid_to_context(secid, secdata, seclen);
5484 }
5485
5486 static int selinux_secctx_to_secid(const char *secdata, u32 seclen, u32 *secid)
5487 {
5488         return security_context_to_sid(secdata, seclen, secid);
5489 }
5490
5491 static void selinux_release_secctx(char *secdata, u32 seclen)
5492 {
5493         kfree(secdata);
5494 }
5495
5496 #ifdef CONFIG_KEYS
5497
5498 static int selinux_key_alloc(struct key *k, const struct cred *cred,
5499                              unsigned long flags)
5500 {
5501         const struct task_security_struct *tsec;
5502         struct key_security_struct *ksec;
5503
5504         ksec = kzalloc(sizeof(struct key_security_struct), GFP_KERNEL);
5505         if (!ksec)
5506                 return -ENOMEM;
5507
5508         tsec = cred->security;
5509         if (tsec->keycreate_sid)
5510                 ksec->sid = tsec->keycreate_sid;
5511         else
5512                 ksec->sid = tsec->sid;
5513
5514         k->security = ksec;
5515         return 0;
5516 }
5517
5518 static void selinux_key_free(struct key *k)
5519 {
5520         struct key_security_struct *ksec = k->security;
5521
5522         k->security = NULL;
5523         kfree(ksec);
5524 }
5525
5526 static int selinux_key_permission(key_ref_t key_ref,
5527                                   const struct cred *cred,
5528                                   key_perm_t perm)
5529 {
5530         struct key *key;
5531         struct key_security_struct *ksec;
5532         u32 sid;
5533
5534         /* if no specific permissions are requested, we skip the
5535            permission check. No serious, additional covert channels
5536            appear to be created. */
5537         if (perm == 0)
5538                 return 0;
5539
5540         sid = cred_sid(cred);
5541
5542         key = key_ref_to_ptr(key_ref);
5543         ksec = key->security;
5544
5545         return avc_has_perm(sid, ksec->sid, SECCLASS_KEY, perm, NULL);
5546 }
5547
5548 static int selinux_key_getsecurity(struct key *key, char **_buffer)
5549 {
5550         struct key_security_struct *ksec = key->security;
5551         char *context = NULL;
5552         unsigned len;
5553         int rc;
5554
5555         rc = security_sid_to_context(ksec->sid, &context, &len);
5556         if (!rc)
5557                 rc = len;
5558         *_buffer = context;
5559         return rc;
5560 }
5561
5562 #endif
5563
5564 static struct security_operations selinux_ops = {
5565         .name =                         "selinux",
5566
5567         .ptrace_may_access =            selinux_ptrace_may_access,
5568         .ptrace_traceme =               selinux_ptrace_traceme,
5569         .capget =                       selinux_capget,
5570         .capset =                       selinux_capset,
5571         .sysctl =                       selinux_sysctl,
5572         .capable =                      selinux_capable,
5573         .quotactl =                     selinux_quotactl,
5574         .quota_on =                     selinux_quota_on,
5575         .syslog =                       selinux_syslog,
5576         .vm_enough_memory =             selinux_vm_enough_memory,
5577
5578         .netlink_send =                 selinux_netlink_send,
5579         .netlink_recv =                 selinux_netlink_recv,
5580
5581         .bprm_set_creds =               selinux_bprm_set_creds,
5582         .bprm_committing_creds =        selinux_bprm_committing_creds,
5583         .bprm_committed_creds =         selinux_bprm_committed_creds,
5584         .bprm_secureexec =              selinux_bprm_secureexec,
5585
5586         .sb_alloc_security =            selinux_sb_alloc_security,
5587         .sb_free_security =             selinux_sb_free_security,
5588         .sb_copy_data =                 selinux_sb_copy_data,
5589         .sb_kern_mount =                selinux_sb_kern_mount,
5590         .sb_show_options =              selinux_sb_show_options,
5591         .sb_statfs =                    selinux_sb_statfs,
5592         .sb_mount =                     selinux_mount,
5593         .sb_umount =                    selinux_umount,
5594         .sb_set_mnt_opts =              selinux_set_mnt_opts,
5595         .sb_clone_mnt_opts =            selinux_sb_clone_mnt_opts,
5596         .sb_parse_opts_str =            selinux_parse_opts_str,
5597
5598
5599         .inode_alloc_security =         selinux_inode_alloc_security,
5600         .inode_free_security =          selinux_inode_free_security,
5601         .inode_init_security =          selinux_inode_init_security,
5602         .inode_create =                 selinux_inode_create,
5603         .inode_link =                   selinux_inode_link,
5604         .inode_unlink =                 selinux_inode_unlink,
5605         .inode_symlink =                selinux_inode_symlink,
5606         .inode_mkdir =                  selinux_inode_mkdir,
5607         .inode_rmdir =                  selinux_inode_rmdir,
5608         .inode_mknod =                  selinux_inode_mknod,
5609         .inode_rename =                 selinux_inode_rename,
5610         .inode_readlink =               selinux_inode_readlink,
5611         .inode_follow_link =            selinux_inode_follow_link,
5612         .inode_permission =             selinux_inode_permission,
5613         .inode_setattr =                selinux_inode_setattr,
5614         .inode_getattr =                selinux_inode_getattr,
5615         .inode_setxattr =               selinux_inode_setxattr,
5616         .inode_post_setxattr =          selinux_inode_post_setxattr,
5617         .inode_getxattr =               selinux_inode_getxattr,
5618         .inode_listxattr =              selinux_inode_listxattr,
5619         .inode_removexattr =            selinux_inode_removexattr,
5620         .inode_getsecurity =            selinux_inode_getsecurity,
5621         .inode_setsecurity =            selinux_inode_setsecurity,
5622         .inode_listsecurity =           selinux_inode_listsecurity,
5623         .inode_need_killpriv =          selinux_inode_need_killpriv,
5624         .inode_killpriv =               selinux_inode_killpriv,
5625         .inode_getsecid =               selinux_inode_getsecid,
5626
5627         .file_permission =              selinux_file_permission,
5628         .file_alloc_security =          selinux_file_alloc_security,
5629         .file_free_security =           selinux_file_free_security,
5630         .file_ioctl =                   selinux_file_ioctl,
5631         .file_mmap =                    selinux_file_mmap,
5632         .file_mprotect =                selinux_file_mprotect,
5633         .file_lock =                    selinux_file_lock,
5634         .file_fcntl =                   selinux_file_fcntl,
5635         .file_set_fowner =              selinux_file_set_fowner,
5636         .file_send_sigiotask =          selinux_file_send_sigiotask,
5637         .file_receive =                 selinux_file_receive,
5638
5639         .dentry_open =                  selinux_dentry_open,
5640
5641         .task_create =                  selinux_task_create,
5642         .cred_free =                    selinux_cred_free,
5643         .cred_prepare =                 selinux_cred_prepare,
5644         .cred_commit =                  selinux_cred_commit,
5645         .kernel_act_as =                selinux_kernel_act_as,
5646         .kernel_create_files_as =       selinux_kernel_create_files_as,
5647         .task_setuid =                  selinux_task_setuid,
5648         .task_fix_setuid =              selinux_task_fix_setuid,
5649         .task_setgid =                  selinux_task_setgid,
5650         .task_setpgid =                 selinux_task_setpgid,
5651         .task_getpgid =                 selinux_task_getpgid,
5652         .task_getsid =                  selinux_task_getsid,
5653         .task_getsecid =                selinux_task_getsecid,
5654         .task_setgroups =               selinux_task_setgroups,
5655         .task_setnice =                 selinux_task_setnice,
5656         .task_setioprio =               selinux_task_setioprio,
5657         .task_getioprio =               selinux_task_getioprio,
5658         .task_setrlimit =               selinux_task_setrlimit,
5659         .task_setscheduler =            selinux_task_setscheduler,
5660         .task_getscheduler =            selinux_task_getscheduler,
5661         .task_movememory =              selinux_task_movememory,
5662         .task_kill =                    selinux_task_kill,
5663         .task_wait =                    selinux_task_wait,
5664         .task_prctl =                   selinux_task_prctl,
5665         .task_to_inode =                selinux_task_to_inode,
5666
5667         .ipc_permission =               selinux_ipc_permission,
5668         .ipc_getsecid =                 selinux_ipc_getsecid,
5669
5670         .msg_msg_alloc_security =       selinux_msg_msg_alloc_security,
5671         .msg_msg_free_security =        selinux_msg_msg_free_security,
5672
5673         .msg_queue_alloc_security =     selinux_msg_queue_alloc_security,
5674         .msg_queue_free_security =      selinux_msg_queue_free_security,
5675         .msg_queue_associate =          selinux_msg_queue_associate,
5676         .msg_queue_msgctl =             selinux_msg_queue_msgctl,
5677         .msg_queue_msgsnd =             selinux_msg_queue_msgsnd,
5678         .msg_queue_msgrcv =             selinux_msg_queue_msgrcv,
5679
5680         .shm_alloc_security =           selinux_shm_alloc_security,
5681         .shm_free_security =            selinux_shm_free_security,
5682         .shm_associate =                selinux_shm_associate,
5683         .shm_shmctl =                   selinux_shm_shmctl,
5684         .shm_shmat =                    selinux_shm_shmat,
5685
5686         .sem_alloc_security =           selinux_sem_alloc_security,
5687         .sem_free_security =            selinux_sem_free_security,
5688         .sem_associate =                selinux_sem_associate,
5689         .sem_semctl =                   selinux_sem_semctl,
5690         .sem_semop =                    selinux_sem_semop,
5691
5692         .d_instantiate =                selinux_d_instantiate,
5693
5694         .getprocattr =                  selinux_getprocattr,
5695         .setprocattr =                  selinux_setprocattr,
5696
5697         .secid_to_secctx =              selinux_secid_to_secctx,
5698         .secctx_to_secid =              selinux_secctx_to_secid,
5699         .release_secctx =               selinux_release_secctx,
5700
5701         .unix_stream_connect =          selinux_socket_unix_stream_connect,
5702         .unix_may_send =                selinux_socket_unix_may_send,
5703
5704         .socket_create =                selinux_socket_create,
5705         .socket_post_create =           selinux_socket_post_create,
5706         .socket_bind =                  selinux_socket_bind,
5707         .socket_connect =               selinux_socket_connect,
5708         .socket_listen =                selinux_socket_listen,
5709         .socket_accept =                selinux_socket_accept,
5710         .socket_sendmsg =               selinux_socket_sendmsg,
5711         .socket_recvmsg =               selinux_socket_recvmsg,
5712         .socket_getsockname =           selinux_socket_getsockname,
5713         .socket_getpeername =           selinux_socket_getpeername,
5714         .socket_getsockopt =            selinux_socket_getsockopt,
5715         .socket_setsockopt =            selinux_socket_setsockopt,
5716         .socket_shutdown =              selinux_socket_shutdown,
5717         .socket_sock_rcv_skb =          selinux_socket_sock_rcv_skb,
5718         .socket_getpeersec_stream =     selinux_socket_getpeersec_stream,
5719         .socket_getpeersec_dgram =      selinux_socket_getpeersec_dgram,
5720         .sk_alloc_security =            selinux_sk_alloc_security,
5721         .sk_free_security =             selinux_sk_free_security,
5722         .sk_clone_security =            selinux_sk_clone_security,
5723         .sk_getsecid =                  selinux_sk_getsecid,
5724         .sock_graft =                   selinux_sock_graft,
5725         .inet_conn_request =            selinux_inet_conn_request,
5726         .inet_csk_clone =               selinux_inet_csk_clone,
5727         .inet_conn_established =        selinux_inet_conn_established,
5728         .req_classify_flow =            selinux_req_classify_flow,
5729
5730 #ifdef CONFIG_SECURITY_NETWORK_XFRM
5731         .xfrm_policy_alloc_security =   selinux_xfrm_policy_alloc,
5732         .xfrm_policy_clone_security =   selinux_xfrm_policy_clone,
5733         .xfrm_policy_free_security =    selinux_xfrm_policy_free,
5734         .xfrm_policy_delete_security =  selinux_xfrm_policy_delete,
5735         .xfrm_state_alloc_security =    selinux_xfrm_state_alloc,
5736         .xfrm_state_free_security =     selinux_xfrm_state_free,
5737         .xfrm_state_delete_security =   selinux_xfrm_state_delete,
5738         .xfrm_policy_lookup =           selinux_xfrm_policy_lookup,
5739         .xfrm_state_pol_flow_match =    selinux_xfrm_state_pol_flow_match,
5740         .xfrm_decode_session =          selinux_xfrm_decode_session,
5741 #endif
5742
5743 #ifdef CONFIG_KEYS
5744         .key_alloc =                    selinux_key_alloc,
5745         .key_free =                     selinux_key_free,
5746         .key_permission =               selinux_key_permission,
5747         .key_getsecurity =              selinux_key_getsecurity,
5748 #endif
5749
5750 #ifdef CONFIG_AUDIT
5751         .audit_rule_init =              selinux_audit_rule_init,
5752         .audit_rule_known =             selinux_audit_rule_known,
5753         .audit_rule_match =             selinux_audit_rule_match,
5754         .audit_rule_free =              selinux_audit_rule_free,
5755 #endif
5756 };
5757
5758 static __init int selinux_init(void)
5759 {
5760         if (!security_module_enable(&selinux_ops)) {
5761                 selinux_enabled = 0;
5762                 return 0;
5763         }
5764
5765         if (!selinux_enabled) {
5766                 printk(KERN_INFO "SELinux:  Disabled at boot.\n");
5767                 return 0;
5768         }
5769
5770         printk(KERN_INFO "SELinux:  Initializing.\n");
5771
5772         /* Set the security state for the initial task. */
5773         cred_init_security();
5774
5775         sel_inode_cache = kmem_cache_create("selinux_inode_security",
5776                                             sizeof(struct inode_security_struct),
5777                                             0, SLAB_PANIC, NULL);
5778         avc_init();
5779
5780         secondary_ops = security_ops;
5781         if (!secondary_ops)
5782                 panic("SELinux: No initial security operations\n");
5783         if (register_security(&selinux_ops))
5784                 panic("SELinux: Unable to register with kernel.\n");
5785
5786         if (selinux_enforcing)
5787                 printk(KERN_DEBUG "SELinux:  Starting in enforcing mode\n");
5788         else
5789                 printk(KERN_DEBUG "SELinux:  Starting in permissive mode\n");
5790
5791         return 0;
5792 }
5793
5794 void selinux_complete_init(void)
5795 {
5796         printk(KERN_DEBUG "SELinux:  Completing initialization.\n");
5797
5798         /* Set up any superblocks initialized prior to the policy load. */
5799         printk(KERN_DEBUG "SELinux:  Setting up existing superblocks.\n");
5800         spin_lock(&sb_lock);
5801         spin_lock(&sb_security_lock);
5802 next_sb:
5803         if (!list_empty(&superblock_security_head)) {
5804                 struct superblock_security_struct *sbsec =
5805                                 list_entry(superblock_security_head.next,
5806                                            struct superblock_security_struct,
5807                                            list);
5808                 struct super_block *sb = sbsec->sb;
5809                 sb->s_count++;
5810                 spin_unlock(&sb_security_lock);
5811                 spin_unlock(&sb_lock);
5812                 down_read(&sb->s_umount);
5813                 if (sb->s_root)
5814                         superblock_doinit(sb, NULL);
5815                 drop_super(sb);
5816                 spin_lock(&sb_lock);
5817                 spin_lock(&sb_security_lock);
5818                 list_del_init(&sbsec->list);
5819                 goto next_sb;
5820         }
5821         spin_unlock(&sb_security_lock);
5822         spin_unlock(&sb_lock);
5823 }
5824
5825 /* SELinux requires early initialization in order to label
5826    all processes and objects when they are created. */
5827 security_initcall(selinux_init);
5828
5829 #if defined(CONFIG_NETFILTER)
5830
5831 static struct nf_hook_ops selinux_ipv4_ops[] = {
5832         {
5833                 .hook =         selinux_ipv4_postroute,
5834                 .owner =        THIS_MODULE,
5835                 .pf =           PF_INET,
5836                 .hooknum =      NF_INET_POST_ROUTING,
5837                 .priority =     NF_IP_PRI_SELINUX_LAST,
5838         },
5839         {
5840                 .hook =         selinux_ipv4_forward,
5841                 .owner =        THIS_MODULE,
5842                 .pf =           PF_INET,
5843                 .hooknum =      NF_INET_FORWARD,
5844                 .priority =     NF_IP_PRI_SELINUX_FIRST,
5845         },
5846         {
5847                 .hook =         selinux_ipv4_output,
5848                 .owner =        THIS_MODULE,
5849                 .pf =           PF_INET,
5850                 .hooknum =      NF_INET_LOCAL_OUT,
5851                 .priority =     NF_IP_PRI_SELINUX_FIRST,
5852         }
5853 };
5854
5855 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
5856
5857 static struct nf_hook_ops selinux_ipv6_ops[] = {
5858         {
5859                 .hook =         selinux_ipv6_postroute,
5860                 .owner =        THIS_MODULE,
5861                 .pf =           PF_INET6,
5862                 .hooknum =      NF_INET_POST_ROUTING,
5863                 .priority =     NF_IP6_PRI_SELINUX_LAST,
5864         },
5865         {
5866                 .hook =         selinux_ipv6_forward,
5867                 .owner =        THIS_MODULE,
5868                 .pf =           PF_INET6,
5869                 .hooknum =      NF_INET_FORWARD,
5870                 .priority =     NF_IP6_PRI_SELINUX_FIRST,
5871         }
5872 };
5873
5874 #endif  /* IPV6 */
5875
5876 static int __init selinux_nf_ip_init(void)
5877 {
5878         int err = 0;
5879
5880         if (!selinux_enabled)
5881                 goto out;
5882
5883         printk(KERN_DEBUG "SELinux:  Registering netfilter hooks\n");
5884
5885         err = nf_register_hooks(selinux_ipv4_ops, ARRAY_SIZE(selinux_ipv4_ops));
5886         if (err)
5887                 panic("SELinux: nf_register_hooks for IPv4: error %d\n", err);
5888
5889 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
5890         err = nf_register_hooks(selinux_ipv6_ops, ARRAY_SIZE(selinux_ipv6_ops));
5891         if (err)
5892                 panic("SELinux: nf_register_hooks for IPv6: error %d\n", err);
5893 #endif  /* IPV6 */
5894
5895 out:
5896         return err;
5897 }
5898
5899 __initcall(selinux_nf_ip_init);
5900
5901 #ifdef CONFIG_SECURITY_SELINUX_DISABLE
5902 static void selinux_nf_ip_exit(void)
5903 {
5904         printk(KERN_DEBUG "SELinux:  Unregistering netfilter hooks\n");
5905
5906         nf_unregister_hooks(selinux_ipv4_ops, ARRAY_SIZE(selinux_ipv4_ops));
5907 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
5908         nf_unregister_hooks(selinux_ipv6_ops, ARRAY_SIZE(selinux_ipv6_ops));
5909 #endif  /* IPV6 */
5910 }
5911 #endif
5912
5913 #else /* CONFIG_NETFILTER */
5914
5915 #ifdef CONFIG_SECURITY_SELINUX_DISABLE
5916 #define selinux_nf_ip_exit()
5917 #endif
5918
5919 #endif /* CONFIG_NETFILTER */
5920
5921 #ifdef CONFIG_SECURITY_SELINUX_DISABLE
5922 static int selinux_disabled;
5923
5924 int selinux_disable(void)
5925 {
5926         extern void exit_sel_fs(void);
5927
5928         if (ss_initialized) {
5929                 /* Not permitted after initial policy load. */
5930                 return -EINVAL;
5931         }
5932
5933         if (selinux_disabled) {
5934                 /* Only do this once. */
5935                 return -EINVAL;
5936         }
5937
5938         printk(KERN_INFO "SELinux:  Disabled at runtime.\n");
5939
5940         selinux_disabled = 1;
5941         selinux_enabled = 0;
5942
5943         /* Reset security_ops to the secondary module, dummy or capability. */
5944         security_ops = secondary_ops;
5945
5946         /* Unregister netfilter hooks. */
5947         selinux_nf_ip_exit();
5948
5949         /* Unregister selinuxfs. */
5950         exit_sel_fs();
5951
5952         return 0;
5953 }
5954 #endif