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_check_security(struct linux_binprm *bprm)
2186 {
2187         return secondary_ops->bprm_check_security(bprm);
2188 }
2189
2190 static int selinux_bprm_secureexec(struct linux_binprm *bprm)
2191 {
2192         const struct cred *cred = current_cred();
2193         const struct task_security_struct *tsec = cred->security;
2194         u32 sid, osid;
2195         int atsecure = 0;
2196
2197         sid = tsec->sid;
2198         osid = tsec->osid;
2199
2200         if (osid != sid) {
2201                 /* Enable secure mode for SIDs transitions unless
2202                    the noatsecure permission is granted between
2203                    the two SIDs, i.e. ahp returns 0. */
2204                 atsecure = avc_has_perm(osid, sid,
2205                                         SECCLASS_PROCESS,
2206                                         PROCESS__NOATSECURE, NULL);
2207         }
2208
2209         return (atsecure || secondary_ops->bprm_secureexec(bprm));
2210 }
2211
2212 extern struct vfsmount *selinuxfs_mount;
2213 extern struct dentry *selinux_null;
2214
2215 /* Derived from fs/exec.c:flush_old_files. */
2216 static inline void flush_unauthorized_files(const struct cred *cred,
2217                                             struct files_struct *files)
2218 {
2219         struct avc_audit_data ad;
2220         struct file *file, *devnull = NULL;
2221         struct tty_struct *tty;
2222         struct fdtable *fdt;
2223         long j = -1;
2224         int drop_tty = 0;
2225
2226         tty = get_current_tty();
2227         if (tty) {
2228                 file_list_lock();
2229                 if (!list_empty(&tty->tty_files)) {
2230                         struct inode *inode;
2231
2232                         /* Revalidate access to controlling tty.
2233                            Use inode_has_perm on the tty inode directly rather
2234                            than using file_has_perm, as this particular open
2235                            file may belong to another process and we are only
2236                            interested in the inode-based check here. */
2237                         file = list_first_entry(&tty->tty_files, struct file, f_u.fu_list);
2238                         inode = file->f_path.dentry->d_inode;
2239                         if (inode_has_perm(cred, inode,
2240                                            FILE__READ | FILE__WRITE, NULL)) {
2241                                 drop_tty = 1;
2242                         }
2243                 }
2244                 file_list_unlock();
2245                 tty_kref_put(tty);
2246         }
2247         /* Reset controlling tty. */
2248         if (drop_tty)
2249                 no_tty();
2250
2251         /* Revalidate access to inherited open files. */
2252
2253         AVC_AUDIT_DATA_INIT(&ad, FS);
2254
2255         spin_lock(&files->file_lock);
2256         for (;;) {
2257                 unsigned long set, i;
2258                 int fd;
2259
2260                 j++;
2261                 i = j * __NFDBITS;
2262                 fdt = files_fdtable(files);
2263                 if (i >= fdt->max_fds)
2264                         break;
2265                 set = fdt->open_fds->fds_bits[j];
2266                 if (!set)
2267                         continue;
2268                 spin_unlock(&files->file_lock);
2269                 for ( ; set ; i++, set >>= 1) {
2270                         if (set & 1) {
2271                                 file = fget(i);
2272                                 if (!file)
2273                                         continue;
2274                                 if (file_has_perm(cred,
2275                                                   file,
2276                                                   file_to_av(file))) {
2277                                         sys_close(i);
2278                                         fd = get_unused_fd();
2279                                         if (fd != i) {
2280                                                 if (fd >= 0)
2281                                                         put_unused_fd(fd);
2282                                                 fput(file);
2283                                                 continue;
2284                                         }
2285                                         if (devnull) {
2286                                                 get_file(devnull);
2287                                         } else {
2288                                                 devnull = dentry_open(
2289                                                         dget(selinux_null),
2290                                                         mntget(selinuxfs_mount),
2291                                                         O_RDWR, cred);
2292                                                 if (IS_ERR(devnull)) {
2293                                                         devnull = NULL;
2294                                                         put_unused_fd(fd);
2295                                                         fput(file);
2296                                                         continue;
2297                                                 }
2298                                         }
2299                                         fd_install(fd, devnull);
2300                                 }
2301                                 fput(file);
2302                         }
2303                 }
2304                 spin_lock(&files->file_lock);
2305
2306         }
2307         spin_unlock(&files->file_lock);
2308 }
2309
2310 /*
2311  * Prepare a process for imminent new credential changes due to exec
2312  */
2313 static void selinux_bprm_committing_creds(struct linux_binprm *bprm)
2314 {
2315         struct task_security_struct *new_tsec;
2316         struct rlimit *rlim, *initrlim;
2317         int rc, i;
2318
2319         secondary_ops->bprm_committing_creds(bprm);
2320
2321         new_tsec = bprm->cred->security;
2322         if (new_tsec->sid == new_tsec->osid)
2323                 return;
2324
2325         /* Close files for which the new task SID is not authorized. */
2326         flush_unauthorized_files(bprm->cred, current->files);
2327
2328         /* Always clear parent death signal on SID transitions. */
2329         current->pdeath_signal = 0;
2330
2331         /* Check whether the new SID can inherit resource limits from the old
2332          * SID.  If not, reset all soft limits to the lower of the current
2333          * task's hard limit and the init task's soft limit.
2334          *
2335          * Note that the setting of hard limits (even to lower them) can be
2336          * controlled by the setrlimit check.  The inclusion of the init task's
2337          * soft limit into the computation is to avoid resetting soft limits
2338          * higher than the default soft limit for cases where the default is
2339          * lower than the hard limit, e.g. RLIMIT_CORE or RLIMIT_STACK.
2340          */
2341         rc = avc_has_perm(new_tsec->osid, new_tsec->sid, SECCLASS_PROCESS,
2342                           PROCESS__RLIMITINH, NULL);
2343         if (rc) {
2344                 for (i = 0; i < RLIM_NLIMITS; i++) {
2345                         rlim = current->signal->rlim + i;
2346                         initrlim = init_task.signal->rlim + i;
2347                         rlim->rlim_cur = min(rlim->rlim_max, initrlim->rlim_cur);
2348                 }
2349                 update_rlimit_cpu(rlim->rlim_cur);
2350         }
2351 }
2352
2353 /*
2354  * Clean up the process immediately after the installation of new credentials
2355  * due to exec
2356  */
2357 static void selinux_bprm_committed_creds(struct linux_binprm *bprm)
2358 {
2359         const struct task_security_struct *tsec = current_security();
2360         struct itimerval itimer;
2361         struct sighand_struct *psig;
2362         u32 osid, sid;
2363         int rc, i;
2364         unsigned long flags;
2365
2366         secondary_ops->bprm_committed_creds(bprm);
2367
2368         osid = tsec->osid;
2369         sid = tsec->sid;
2370
2371         if (sid == osid)
2372                 return;
2373
2374         /* Check whether the new SID can inherit signal state from the old SID.
2375          * If not, clear itimers to avoid subsequent signal generation and
2376          * flush and unblock signals.
2377          *
2378          * This must occur _after_ the task SID has been updated so that any
2379          * kill done after the flush will be checked against the new SID.
2380          */
2381         rc = avc_has_perm(osid, sid, SECCLASS_PROCESS, PROCESS__SIGINH, NULL);
2382         if (rc) {
2383                 memset(&itimer, 0, sizeof itimer);
2384                 for (i = 0; i < 3; i++)
2385                         do_setitimer(i, &itimer, NULL);
2386                 flush_signals(current);
2387                 spin_lock_irq(&current->sighand->siglock);
2388                 flush_signal_handlers(current, 1);
2389                 sigemptyset(&current->blocked);
2390                 recalc_sigpending();
2391                 spin_unlock_irq(&current->sighand->siglock);
2392         }
2393
2394         /* Wake up the parent if it is waiting so that it can recheck
2395          * wait permission to the new task SID. */
2396         read_lock_irq(&tasklist_lock);
2397         psig = current->parent->sighand;
2398         spin_lock_irqsave(&psig->siglock, flags);
2399         wake_up_interruptible(&current->parent->signal->wait_chldexit);
2400         spin_unlock_irqrestore(&psig->siglock, flags);
2401         read_unlock_irq(&tasklist_lock);
2402 }
2403
2404 /* superblock security operations */
2405
2406 static int selinux_sb_alloc_security(struct super_block *sb)
2407 {
2408         return superblock_alloc_security(sb);
2409 }
2410
2411 static void selinux_sb_free_security(struct super_block *sb)
2412 {
2413         superblock_free_security(sb);
2414 }
2415
2416 static inline int match_prefix(char *prefix, int plen, char *option, int olen)
2417 {
2418         if (plen > olen)
2419                 return 0;
2420
2421         return !memcmp(prefix, option, plen);
2422 }
2423
2424 static inline int selinux_option(char *option, int len)
2425 {
2426         return (match_prefix(CONTEXT_STR, sizeof(CONTEXT_STR)-1, option, len) ||
2427                 match_prefix(FSCONTEXT_STR, sizeof(FSCONTEXT_STR)-1, option, len) ||
2428                 match_prefix(DEFCONTEXT_STR, sizeof(DEFCONTEXT_STR)-1, option, len) ||
2429                 match_prefix(ROOTCONTEXT_STR, sizeof(ROOTCONTEXT_STR)-1, option, len) ||
2430                 match_prefix(LABELSUPP_STR, sizeof(LABELSUPP_STR)-1, option, len));
2431 }
2432
2433 static inline void take_option(char **to, char *from, int *first, int len)
2434 {
2435         if (!*first) {
2436                 **to = ',';
2437                 *to += 1;
2438         } else
2439                 *first = 0;
2440         memcpy(*to, from, len);
2441         *to += len;
2442 }
2443
2444 static inline void take_selinux_option(char **to, char *from, int *first,
2445                                        int len)
2446 {
2447         int current_size = 0;
2448
2449         if (!*first) {
2450                 **to = '|';
2451                 *to += 1;
2452         } else
2453                 *first = 0;
2454
2455         while (current_size < len) {
2456                 if (*from != '"') {
2457                         **to = *from;
2458                         *to += 1;
2459                 }
2460                 from += 1;
2461                 current_size += 1;
2462         }
2463 }
2464
2465 static int selinux_sb_copy_data(char *orig, char *copy)
2466 {
2467         int fnosec, fsec, rc = 0;
2468         char *in_save, *in_curr, *in_end;
2469         char *sec_curr, *nosec_save, *nosec;
2470         int open_quote = 0;
2471
2472         in_curr = orig;
2473         sec_curr = copy;
2474
2475         nosec = (char *)get_zeroed_page(GFP_KERNEL);
2476         if (!nosec) {
2477                 rc = -ENOMEM;
2478                 goto out;
2479         }
2480
2481         nosec_save = nosec;
2482         fnosec = fsec = 1;
2483         in_save = in_end = orig;
2484
2485         do {
2486                 if (*in_end == '"')
2487                         open_quote = !open_quote;
2488                 if ((*in_end == ',' && open_quote == 0) ||
2489                                 *in_end == '\0') {
2490                         int len = in_end - in_curr;
2491
2492                         if (selinux_option(in_curr, len))
2493                                 take_selinux_option(&sec_curr, in_curr, &fsec, len);
2494                         else
2495                                 take_option(&nosec, in_curr, &fnosec, len);
2496
2497                         in_curr = in_end + 1;
2498                 }
2499         } while (*in_end++);
2500
2501         strcpy(in_save, nosec_save);
2502         free_page((unsigned long)nosec_save);
2503 out:
2504         return rc;
2505 }
2506
2507 static int selinux_sb_kern_mount(struct super_block *sb, int flags, void *data)
2508 {
2509         const struct cred *cred = current_cred();
2510         struct avc_audit_data ad;
2511         int rc;
2512
2513         rc = superblock_doinit(sb, data);
2514         if (rc)
2515                 return rc;
2516
2517         /* Allow all mounts performed by the kernel */
2518         if (flags & MS_KERNMOUNT)
2519                 return 0;
2520
2521         AVC_AUDIT_DATA_INIT(&ad, FS);
2522         ad.u.fs.path.dentry = sb->s_root;
2523         return superblock_has_perm(cred, sb, FILESYSTEM__MOUNT, &ad);
2524 }
2525
2526 static int selinux_sb_statfs(struct dentry *dentry)
2527 {
2528         const struct cred *cred = current_cred();
2529         struct avc_audit_data ad;
2530
2531         AVC_AUDIT_DATA_INIT(&ad, FS);
2532         ad.u.fs.path.dentry = dentry->d_sb->s_root;
2533         return superblock_has_perm(cred, dentry->d_sb, FILESYSTEM__GETATTR, &ad);
2534 }
2535
2536 static int selinux_mount(char *dev_name,
2537                          struct path *path,
2538                          char *type,
2539                          unsigned long flags,
2540                          void *data)
2541 {
2542         const struct cred *cred = current_cred();
2543         int rc;
2544
2545         rc = secondary_ops->sb_mount(dev_name, path, type, flags, data);
2546         if (rc)
2547                 return rc;
2548
2549         if (flags & MS_REMOUNT)
2550                 return superblock_has_perm(cred, path->mnt->mnt_sb,
2551                                            FILESYSTEM__REMOUNT, NULL);
2552         else
2553                 return dentry_has_perm(cred, path->mnt, path->dentry,
2554                                        FILE__MOUNTON);
2555 }
2556
2557 static int selinux_umount(struct vfsmount *mnt, int flags)
2558 {
2559         const struct cred *cred = current_cred();
2560         int rc;
2561
2562         rc = secondary_ops->sb_umount(mnt, flags);
2563         if (rc)
2564                 return rc;
2565
2566         return superblock_has_perm(cred, mnt->mnt_sb,
2567                                    FILESYSTEM__UNMOUNT, NULL);
2568 }
2569
2570 /* inode security operations */
2571
2572 static int selinux_inode_alloc_security(struct inode *inode)
2573 {
2574         return inode_alloc_security(inode);
2575 }
2576
2577 static void selinux_inode_free_security(struct inode *inode)
2578 {
2579         inode_free_security(inode);
2580 }
2581
2582 static int selinux_inode_init_security(struct inode *inode, struct inode *dir,
2583                                        char **name, void **value,
2584                                        size_t *len)
2585 {
2586         const struct cred *cred = current_cred();
2587         const struct task_security_struct *tsec = cred->security;
2588         struct inode_security_struct *dsec;
2589         struct superblock_security_struct *sbsec;
2590         u32 sid, newsid, clen;
2591         int rc;
2592         char *namep = NULL, *context;
2593
2594         dsec = dir->i_security;
2595         sbsec = dir->i_sb->s_security;
2596
2597         sid = tsec->sid;
2598         newsid = tsec->create_sid;
2599
2600         if (!newsid || !(sbsec->flags & SE_SBLABELSUPP)) {
2601                 rc = security_transition_sid(sid, dsec->sid,
2602                                              inode_mode_to_security_class(inode->i_mode),
2603                                              &newsid);
2604                 if (rc) {
2605                         printk(KERN_WARNING "%s:  "
2606                                "security_transition_sid failed, rc=%d (dev=%s "
2607                                "ino=%ld)\n",
2608                                __func__,
2609                                -rc, inode->i_sb->s_id, inode->i_ino);
2610                         return rc;
2611                 }
2612         }
2613
2614         /* Possibly defer initialization to selinux_complete_init. */
2615         if (sbsec->flags & SE_SBINITIALIZED) {
2616                 struct inode_security_struct *isec = inode->i_security;
2617                 isec->sclass = inode_mode_to_security_class(inode->i_mode);
2618                 isec->sid = newsid;
2619                 isec->initialized = 1;
2620         }
2621
2622         if (!ss_initialized || !(sbsec->flags & SE_SBLABELSUPP))
2623                 return -EOPNOTSUPP;
2624
2625         if (name) {
2626                 namep = kstrdup(XATTR_SELINUX_SUFFIX, GFP_NOFS);
2627                 if (!namep)
2628                         return -ENOMEM;
2629                 *name = namep;
2630         }
2631
2632         if (value && len) {
2633                 rc = security_sid_to_context_force(newsid, &context, &clen);
2634                 if (rc) {
2635                         kfree(namep);
2636                         return rc;
2637                 }
2638                 *value = context;
2639                 *len = clen;
2640         }
2641
2642         return 0;
2643 }
2644
2645 static int selinux_inode_create(struct inode *dir, struct dentry *dentry, int mask)
2646 {
2647         return may_create(dir, dentry, SECCLASS_FILE);
2648 }
2649
2650 static int selinux_inode_link(struct dentry *old_dentry, struct inode *dir, struct dentry *new_dentry)
2651 {
2652         int rc;
2653
2654         rc = secondary_ops->inode_link(old_dentry, dir, new_dentry);
2655         if (rc)
2656                 return rc;
2657         return may_link(dir, old_dentry, MAY_LINK);
2658 }
2659
2660 static int selinux_inode_unlink(struct inode *dir, struct dentry *dentry)
2661 {
2662         int rc;
2663
2664         rc = secondary_ops->inode_unlink(dir, dentry);
2665         if (rc)
2666                 return rc;
2667         return may_link(dir, dentry, MAY_UNLINK);
2668 }
2669
2670 static int selinux_inode_symlink(struct inode *dir, struct dentry *dentry, const char *name)
2671 {
2672         return may_create(dir, dentry, SECCLASS_LNK_FILE);
2673 }
2674
2675 static int selinux_inode_mkdir(struct inode *dir, struct dentry *dentry, int mask)
2676 {
2677         return may_create(dir, dentry, SECCLASS_DIR);
2678 }
2679
2680 static int selinux_inode_rmdir(struct inode *dir, struct dentry *dentry)
2681 {
2682         return may_link(dir, dentry, MAY_RMDIR);
2683 }
2684
2685 static int selinux_inode_mknod(struct inode *dir, struct dentry *dentry, int mode, dev_t dev)
2686 {
2687         int rc;
2688
2689         rc = secondary_ops->inode_mknod(dir, dentry, mode, dev);
2690         if (rc)
2691                 return rc;
2692
2693         return may_create(dir, dentry, inode_mode_to_security_class(mode));
2694 }
2695
2696 static int selinux_inode_rename(struct inode *old_inode, struct dentry *old_dentry,
2697                                 struct inode *new_inode, struct dentry *new_dentry)
2698 {
2699         return may_rename(old_inode, old_dentry, new_inode, new_dentry);
2700 }
2701
2702 static int selinux_inode_readlink(struct dentry *dentry)
2703 {
2704         const struct cred *cred = current_cred();
2705
2706         return dentry_has_perm(cred, NULL, dentry, FILE__READ);
2707 }
2708
2709 static int selinux_inode_follow_link(struct dentry *dentry, struct nameidata *nameidata)
2710 {
2711         const struct cred *cred = current_cred();
2712         int rc;
2713
2714         rc = secondary_ops->inode_follow_link(dentry, nameidata);
2715         if (rc)
2716                 return rc;
2717         return dentry_has_perm(cred, NULL, dentry, FILE__READ);
2718 }
2719
2720 static int selinux_inode_permission(struct inode *inode, int mask)
2721 {
2722         const struct cred *cred = current_cred();
2723         int rc;
2724
2725         rc = secondary_ops->inode_permission(inode, mask);
2726         if (rc)
2727                 return rc;
2728
2729         if (!mask) {
2730                 /* No permission to check.  Existence test. */
2731                 return 0;
2732         }
2733
2734         return inode_has_perm(cred, inode,
2735                               file_mask_to_av(inode->i_mode, mask), NULL);
2736 }
2737
2738 static int selinux_inode_setattr(struct dentry *dentry, struct iattr *iattr)
2739 {
2740         const struct cred *cred = current_cred();
2741         int rc;
2742
2743         rc = secondary_ops->inode_setattr(dentry, iattr);
2744         if (rc)
2745                 return rc;
2746
2747         if (iattr->ia_valid & ATTR_FORCE)
2748                 return 0;
2749
2750         if (iattr->ia_valid & (ATTR_MODE | ATTR_UID | ATTR_GID |
2751                                ATTR_ATIME_SET | ATTR_MTIME_SET))
2752                 return dentry_has_perm(cred, NULL, dentry, FILE__SETATTR);
2753
2754         return dentry_has_perm(cred, NULL, dentry, FILE__WRITE);
2755 }
2756
2757 static int selinux_inode_getattr(struct vfsmount *mnt, struct dentry *dentry)
2758 {
2759         const struct cred *cred = current_cred();
2760
2761         return dentry_has_perm(cred, mnt, dentry, FILE__GETATTR);
2762 }
2763
2764 static int selinux_inode_setotherxattr(struct dentry *dentry, const char *name)
2765 {
2766         const struct cred *cred = current_cred();
2767
2768         if (!strncmp(name, XATTR_SECURITY_PREFIX,
2769                      sizeof XATTR_SECURITY_PREFIX - 1)) {
2770                 if (!strcmp(name, XATTR_NAME_CAPS)) {
2771                         if (!capable(CAP_SETFCAP))
2772                                 return -EPERM;
2773                 } else if (!capable(CAP_SYS_ADMIN)) {
2774                         /* A different attribute in the security namespace.
2775                            Restrict to administrator. */
2776                         return -EPERM;
2777                 }
2778         }
2779
2780         /* Not an attribute we recognize, so just check the
2781            ordinary setattr permission. */
2782         return dentry_has_perm(cred, NULL, dentry, FILE__SETATTR);
2783 }
2784
2785 static int selinux_inode_setxattr(struct dentry *dentry, const char *name,
2786                                   const void *value, size_t size, int flags)
2787 {
2788         struct inode *inode = dentry->d_inode;
2789         struct inode_security_struct *isec = inode->i_security;
2790         struct superblock_security_struct *sbsec;
2791         struct avc_audit_data ad;
2792         u32 newsid, sid = current_sid();
2793         int rc = 0;
2794
2795         if (strcmp(name, XATTR_NAME_SELINUX))
2796                 return selinux_inode_setotherxattr(dentry, name);
2797
2798         sbsec = inode->i_sb->s_security;
2799         if (!(sbsec->flags & SE_SBLABELSUPP))
2800                 return -EOPNOTSUPP;
2801
2802         if (!is_owner_or_cap(inode))
2803                 return -EPERM;
2804
2805         AVC_AUDIT_DATA_INIT(&ad, FS);
2806         ad.u.fs.path.dentry = dentry;
2807
2808         rc = avc_has_perm(sid, isec->sid, isec->sclass,
2809                           FILE__RELABELFROM, &ad);
2810         if (rc)
2811                 return rc;
2812
2813         rc = security_context_to_sid(value, size, &newsid);
2814         if (rc == -EINVAL) {
2815                 if (!capable(CAP_MAC_ADMIN))
2816                         return rc;
2817                 rc = security_context_to_sid_force(value, size, &newsid);
2818         }
2819         if (rc)
2820                 return rc;
2821
2822         rc = avc_has_perm(sid, newsid, isec->sclass,
2823                           FILE__RELABELTO, &ad);
2824         if (rc)
2825                 return rc;
2826
2827         rc = security_validate_transition(isec->sid, newsid, sid,
2828                                           isec->sclass);
2829         if (rc)
2830                 return rc;
2831
2832         return avc_has_perm(newsid,
2833                             sbsec->sid,
2834                             SECCLASS_FILESYSTEM,
2835                             FILESYSTEM__ASSOCIATE,
2836                             &ad);
2837 }
2838
2839 static void selinux_inode_post_setxattr(struct dentry *dentry, const char *name,
2840                                         const void *value, size_t size,
2841                                         int flags)
2842 {
2843         struct inode *inode = dentry->d_inode;
2844         struct inode_security_struct *isec = inode->i_security;
2845         u32 newsid;
2846         int rc;
2847
2848         if (strcmp(name, XATTR_NAME_SELINUX)) {
2849                 /* Not an attribute we recognize, so nothing to do. */
2850                 return;
2851         }
2852
2853         rc = security_context_to_sid_force(value, size, &newsid);
2854         if (rc) {
2855                 printk(KERN_ERR "SELinux:  unable to map context to SID"
2856                        "for (%s, %lu), rc=%d\n",
2857                        inode->i_sb->s_id, inode->i_ino, -rc);
2858                 return;
2859         }
2860
2861         isec->sid = newsid;
2862         return;
2863 }
2864
2865 static int selinux_inode_getxattr(struct dentry *dentry, const char *name)
2866 {
2867         const struct cred *cred = current_cred();
2868
2869         return dentry_has_perm(cred, NULL, dentry, FILE__GETATTR);
2870 }
2871
2872 static int selinux_inode_listxattr(struct dentry *dentry)
2873 {
2874         const struct cred *cred = current_cred();
2875
2876         return dentry_has_perm(cred, NULL, dentry, FILE__GETATTR);
2877 }
2878
2879 static int selinux_inode_removexattr(struct dentry *dentry, const char *name)
2880 {
2881         if (strcmp(name, XATTR_NAME_SELINUX))
2882                 return selinux_inode_setotherxattr(dentry, name);
2883
2884         /* No one is allowed to remove a SELinux security label.
2885            You can change the label, but all data must be labeled. */
2886         return -EACCES;
2887 }
2888
2889 /*
2890  * Copy the inode security context value to the user.
2891  *
2892  * Permission check is handled by selinux_inode_getxattr hook.
2893  */
2894 static int selinux_inode_getsecurity(const struct inode *inode, const char *name, void **buffer, bool alloc)
2895 {
2896         u32 size;
2897         int error;
2898         char *context = NULL;
2899         struct inode_security_struct *isec = inode->i_security;
2900
2901         if (strcmp(name, XATTR_SELINUX_SUFFIX))
2902                 return -EOPNOTSUPP;
2903
2904         /*
2905          * If the caller has CAP_MAC_ADMIN, then get the raw context
2906          * value even if it is not defined by current policy; otherwise,
2907          * use the in-core value under current policy.
2908          * Use the non-auditing forms of the permission checks since
2909          * getxattr may be called by unprivileged processes commonly
2910          * and lack of permission just means that we fall back to the
2911          * in-core context value, not a denial.
2912          */
2913         error = selinux_capable(current, current_cred(), CAP_MAC_ADMIN,
2914                                 SECURITY_CAP_NOAUDIT);
2915         if (!error)
2916                 error = security_sid_to_context_force(isec->sid, &context,
2917                                                       &size);
2918         else
2919                 error = security_sid_to_context(isec->sid, &context, &size);
2920         if (error)
2921                 return error;
2922         error = size;
2923         if (alloc) {
2924                 *buffer = context;
2925                 goto out_nofree;
2926         }
2927         kfree(context);
2928 out_nofree:
2929         return error;
2930 }
2931
2932 static int selinux_inode_setsecurity(struct inode *inode, const char *name,
2933                                      const void *value, size_t size, int flags)
2934 {
2935         struct inode_security_struct *isec = inode->i_security;
2936         u32 newsid;
2937         int rc;
2938
2939         if (strcmp(name, XATTR_SELINUX_SUFFIX))
2940                 return -EOPNOTSUPP;
2941
2942         if (!value || !size)
2943                 return -EACCES;
2944
2945         rc = security_context_to_sid((void *)value, size, &newsid);
2946         if (rc)
2947                 return rc;
2948
2949         isec->sid = newsid;
2950         return 0;
2951 }
2952
2953 static int selinux_inode_listsecurity(struct inode *inode, char *buffer, size_t buffer_size)
2954 {
2955         const int len = sizeof(XATTR_NAME_SELINUX);
2956         if (buffer && len <= buffer_size)
2957                 memcpy(buffer, XATTR_NAME_SELINUX, len);
2958         return len;
2959 }
2960
2961 static int selinux_inode_need_killpriv(struct dentry *dentry)
2962 {
2963         return secondary_ops->inode_need_killpriv(dentry);
2964 }
2965
2966 static int selinux_inode_killpriv(struct dentry *dentry)
2967 {
2968         return secondary_ops->inode_killpriv(dentry);
2969 }
2970
2971 static void selinux_inode_getsecid(const struct inode *inode, u32 *secid)
2972 {
2973         struct inode_security_struct *isec = inode->i_security;
2974         *secid = isec->sid;
2975 }
2976
2977 /* file security operations */
2978
2979 static int selinux_revalidate_file_permission(struct file *file, int mask)
2980 {
2981         const struct cred *cred = current_cred();
2982         int rc;
2983         struct inode *inode = file->f_path.dentry->d_inode;
2984
2985         if (!mask) {
2986                 /* No permission to check.  Existence test. */
2987                 return 0;
2988         }
2989
2990         /* file_mask_to_av won't add FILE__WRITE if MAY_APPEND is set */
2991         if ((file->f_flags & O_APPEND) && (mask & MAY_WRITE))
2992                 mask |= MAY_APPEND;
2993
2994         rc = file_has_perm(cred, file,
2995                            file_mask_to_av(inode->i_mode, mask));
2996         if (rc)
2997                 return rc;
2998
2999         return selinux_netlbl_inode_permission(inode, mask);
3000 }
3001
3002 static int selinux_file_permission(struct file *file, int mask)
3003 {
3004         struct inode *inode = file->f_path.dentry->d_inode;
3005         struct file_security_struct *fsec = file->f_security;
3006         struct inode_security_struct *isec = inode->i_security;
3007         u32 sid = current_sid();
3008
3009         if (!mask) {
3010                 /* No permission to check.  Existence test. */
3011                 return 0;
3012         }
3013
3014         if (sid == fsec->sid && fsec->isid == isec->sid
3015             && fsec->pseqno == avc_policy_seqno())
3016                 return selinux_netlbl_inode_permission(inode, mask);
3017
3018         return selinux_revalidate_file_permission(file, mask);
3019 }
3020
3021 static int selinux_file_alloc_security(struct file *file)
3022 {
3023         return file_alloc_security(file);
3024 }
3025
3026 static void selinux_file_free_security(struct file *file)
3027 {
3028         file_free_security(file);
3029 }
3030
3031 static int selinux_file_ioctl(struct file *file, unsigned int cmd,
3032                               unsigned long arg)
3033 {
3034         const struct cred *cred = current_cred();
3035         u32 av = 0;
3036
3037         if (_IOC_DIR(cmd) & _IOC_WRITE)
3038                 av |= FILE__WRITE;
3039         if (_IOC_DIR(cmd) & _IOC_READ)
3040                 av |= FILE__READ;
3041         if (!av)
3042                 av = FILE__IOCTL;
3043
3044         return file_has_perm(cred, file, av);
3045 }
3046
3047 static int file_map_prot_check(struct file *file, unsigned long prot, int shared)
3048 {
3049         const struct cred *cred = current_cred();
3050         int rc = 0;
3051
3052 #ifndef CONFIG_PPC32
3053         if ((prot & PROT_EXEC) && (!file || (!shared && (prot & PROT_WRITE)))) {
3054                 /*
3055                  * We are making executable an anonymous mapping or a
3056                  * private file mapping that will also be writable.
3057                  * This has an additional check.
3058                  */
3059                 rc = cred_has_perm(cred, cred, PROCESS__EXECMEM);
3060                 if (rc)
3061                         goto error;
3062         }
3063 #endif
3064
3065         if (file) {
3066                 /* read access is always possible with a mapping */
3067                 u32 av = FILE__READ;
3068
3069                 /* write access only matters if the mapping is shared */
3070                 if (shared && (prot & PROT_WRITE))
3071                         av |= FILE__WRITE;
3072
3073                 if (prot & PROT_EXEC)
3074                         av |= FILE__EXECUTE;
3075
3076                 return file_has_perm(cred, file, av);
3077         }
3078
3079 error:
3080         return rc;
3081 }
3082
3083 static int selinux_file_mmap(struct file *file, unsigned long reqprot,
3084                              unsigned long prot, unsigned long flags,
3085                              unsigned long addr, unsigned long addr_only)
3086 {
3087         int rc = 0;
3088         u32 sid = current_sid();
3089
3090         if (addr < mmap_min_addr)
3091                 rc = avc_has_perm(sid, sid, SECCLASS_MEMPROTECT,
3092                                   MEMPROTECT__MMAP_ZERO, NULL);
3093         if (rc || addr_only)
3094                 return rc;
3095
3096         if (selinux_checkreqprot)
3097                 prot = reqprot;
3098
3099         return file_map_prot_check(file, prot,
3100                                    (flags & MAP_TYPE) == MAP_SHARED);
3101 }
3102
3103 static int selinux_file_mprotect(struct vm_area_struct *vma,
3104                                  unsigned long reqprot,
3105                                  unsigned long prot)
3106 {
3107         const struct cred *cred = current_cred();
3108         int rc;
3109
3110         rc = secondary_ops->file_mprotect(vma, reqprot, prot);
3111         if (rc)
3112                 return rc;
3113
3114         if (selinux_checkreqprot)
3115                 prot = reqprot;
3116
3117 #ifndef CONFIG_PPC32
3118         if ((prot & PROT_EXEC) && !(vma->vm_flags & VM_EXEC)) {
3119                 rc = 0;
3120                 if (vma->vm_start >= vma->vm_mm->start_brk &&
3121                     vma->vm_end <= vma->vm_mm->brk) {
3122                         rc = cred_has_perm(cred, cred, PROCESS__EXECHEAP);
3123                 } else if (!vma->vm_file &&
3124                            vma->vm_start <= vma->vm_mm->start_stack &&
3125                            vma->vm_end >= vma->vm_mm->start_stack) {
3126                         rc = current_has_perm(current, PROCESS__EXECSTACK);
3127                 } else if (vma->vm_file && vma->anon_vma) {
3128                         /*
3129                          * We are making executable a file mapping that has
3130                          * had some COW done. Since pages might have been
3131                          * written, check ability to execute the possibly
3132                          * modified content.  This typically should only
3133                          * occur for text relocations.
3134                          */
3135                         rc = file_has_perm(cred, vma->vm_file, FILE__EXECMOD);
3136                 }
3137                 if (rc)
3138                         return rc;
3139         }
3140 #endif
3141
3142         return file_map_prot_check(vma->vm_file, prot, vma->vm_flags&VM_SHARED);
3143 }
3144
3145 static int selinux_file_lock(struct file *file, unsigned int cmd)
3146 {
3147         const struct cred *cred = current_cred();
3148
3149         return file_has_perm(cred, file, FILE__LOCK);
3150 }
3151
3152 static int selinux_file_fcntl(struct file *file, unsigned int cmd,
3153                               unsigned long arg)
3154 {
3155         const struct cred *cred = current_cred();
3156         int err = 0;
3157
3158         switch (cmd) {
3159         case F_SETFL:
3160                 if (!file->f_path.dentry || !file->f_path.dentry->d_inode) {
3161                         err = -EINVAL;
3162                         break;
3163                 }
3164
3165                 if ((file->f_flags & O_APPEND) && !(arg & O_APPEND)) {
3166                         err = file_has_perm(cred, file, FILE__WRITE);
3167                         break;
3168                 }
3169                 /* fall through */
3170         case F_SETOWN:
3171         case F_SETSIG:
3172         case F_GETFL:
3173         case F_GETOWN:
3174         case F_GETSIG:
3175                 /* Just check FD__USE permission */
3176                 err = file_has_perm(cred, file, 0);
3177                 break;
3178         case F_GETLK:
3179         case F_SETLK:
3180         case F_SETLKW:
3181 #if BITS_PER_LONG == 32
3182         case F_GETLK64:
3183         case F_SETLK64:
3184         case F_SETLKW64:
3185 #endif
3186                 if (!file->f_path.dentry || !file->f_path.dentry->d_inode) {
3187                         err = -EINVAL;
3188                         break;
3189                 }
3190                 err = file_has_perm(cred, file, FILE__LOCK);
3191                 break;
3192         }
3193
3194         return err;
3195 }
3196
3197 static int selinux_file_set_fowner(struct file *file)
3198 {
3199         struct file_security_struct *fsec;
3200
3201         fsec = file->f_security;
3202         fsec->fown_sid = current_sid();
3203
3204         return 0;
3205 }
3206
3207 static int selinux_file_send_sigiotask(struct task_struct *tsk,
3208                                        struct fown_struct *fown, int signum)
3209 {
3210         struct file *file;
3211         u32 sid = current_sid();
3212         u32 perm;
3213         struct file_security_struct *fsec;
3214
3215         /* struct fown_struct is never outside the context of a struct file */
3216         file = container_of(fown, struct file, f_owner);
3217
3218         fsec = file->f_security;
3219
3220         if (!signum)
3221                 perm = signal_to_av(SIGIO); /* as per send_sigio_to_task */
3222         else
3223                 perm = signal_to_av(signum);
3224
3225         return avc_has_perm(fsec->fown_sid, sid,
3226                             SECCLASS_PROCESS, perm, NULL);
3227 }
3228
3229 static int selinux_file_receive(struct file *file)
3230 {
3231         const struct cred *cred = current_cred();
3232
3233         return file_has_perm(cred, file, file_to_av(file));
3234 }
3235
3236 static int selinux_dentry_open(struct file *file, const struct cred *cred)
3237 {
3238         struct file_security_struct *fsec;
3239         struct inode *inode;
3240         struct inode_security_struct *isec;
3241
3242         inode = file->f_path.dentry->d_inode;
3243         fsec = file->f_security;
3244         isec = inode->i_security;
3245         /*
3246          * Save inode label and policy sequence number
3247          * at open-time so that selinux_file_permission
3248          * can determine whether revalidation is necessary.
3249          * Task label is already saved in the file security
3250          * struct as its SID.
3251          */
3252         fsec->isid = isec->sid;
3253         fsec->pseqno = avc_policy_seqno();
3254         /*
3255          * Since the inode label or policy seqno may have changed
3256          * between the selinux_inode_permission check and the saving
3257          * of state above, recheck that access is still permitted.
3258          * Otherwise, access might never be revalidated against the
3259          * new inode label or new policy.
3260          * This check is not redundant - do not remove.
3261          */
3262         return inode_has_perm(cred, inode, open_file_to_av(file), NULL);
3263 }
3264
3265 /* task security operations */
3266
3267 static int selinux_task_create(unsigned long clone_flags)
3268 {
3269         int rc;
3270
3271         rc = secondary_ops->task_create(clone_flags);
3272         if (rc)
3273                 return rc;
3274
3275         return current_has_perm(current, PROCESS__FORK);
3276 }
3277
3278 /*
3279  * detach and free the LSM part of a set of credentials
3280  */
3281 static void selinux_cred_free(struct cred *cred)
3282 {
3283         struct task_security_struct *tsec = cred->security;
3284         cred->security = NULL;
3285         kfree(tsec);
3286 }
3287
3288 /*
3289  * prepare a new set of credentials for modification
3290  */
3291 static int selinux_cred_prepare(struct cred *new, const struct cred *old,
3292                                 gfp_t gfp)
3293 {
3294         const struct task_security_struct *old_tsec;
3295         struct task_security_struct *tsec;
3296
3297         old_tsec = old->security;
3298
3299         tsec = kmemdup(old_tsec, sizeof(struct task_security_struct), gfp);
3300         if (!tsec)
3301                 return -ENOMEM;
3302
3303         new->security = tsec;
3304         return 0;
3305 }
3306
3307 /*
3308  * commit new credentials
3309  */
3310 static void selinux_cred_commit(struct cred *new, const struct cred *old)
3311 {
3312         secondary_ops->cred_commit(new, old);
3313 }
3314
3315 /*
3316  * set the security data for a kernel service
3317  * - all the creation contexts are set to unlabelled
3318  */
3319 static int selinux_kernel_act_as(struct cred *new, u32 secid)
3320 {
3321         struct task_security_struct *tsec = new->security;
3322         u32 sid = current_sid();
3323         int ret;
3324
3325         ret = avc_has_perm(sid, secid,
3326                            SECCLASS_KERNEL_SERVICE,
3327                            KERNEL_SERVICE__USE_AS_OVERRIDE,
3328                            NULL);
3329         if (ret == 0) {
3330                 tsec->sid = secid;
3331                 tsec->create_sid = 0;
3332                 tsec->keycreate_sid = 0;
3333                 tsec->sockcreate_sid = 0;
3334         }
3335         return ret;
3336 }
3337
3338 /*
3339  * set the file creation context in a security record to the same as the
3340  * objective context of the specified inode
3341  */
3342 static int selinux_kernel_create_files_as(struct cred *new, struct inode *inode)
3343 {
3344         struct inode_security_struct *isec = inode->i_security;
3345         struct task_security_struct *tsec = new->security;
3346         u32 sid = current_sid();
3347         int ret;
3348
3349         ret = avc_has_perm(sid, isec->sid,
3350                            SECCLASS_KERNEL_SERVICE,
3351                            KERNEL_SERVICE__CREATE_FILES_AS,
3352                            NULL);
3353
3354         if (ret == 0)
3355                 tsec->create_sid = isec->sid;
3356         return 0;
3357 }
3358
3359 static int selinux_task_setuid(uid_t id0, uid_t id1, uid_t id2, int flags)
3360 {
3361         /* Since setuid only affects the current process, and
3362            since the SELinux controls are not based on the Linux
3363            identity attributes, SELinux does not need to control
3364            this operation.  However, SELinux does control the use
3365            of the CAP_SETUID and CAP_SETGID capabilities using the
3366            capable hook. */
3367         return 0;
3368 }
3369
3370 static int selinux_task_fix_setuid(struct cred *new, const struct cred *old,
3371                                    int flags)
3372 {
3373         return secondary_ops->task_fix_setuid(new, old, flags);
3374 }
3375
3376 static int selinux_task_setgid(gid_t id0, gid_t id1, gid_t id2, int flags)
3377 {
3378         /* See the comment for setuid above. */
3379         return 0;
3380 }
3381
3382 static int selinux_task_setpgid(struct task_struct *p, pid_t pgid)
3383 {
3384         return current_has_perm(p, PROCESS__SETPGID);
3385 }
3386
3387 static int selinux_task_getpgid(struct task_struct *p)
3388 {
3389         return current_has_perm(p, PROCESS__GETPGID);
3390 }
3391
3392 static int selinux_task_getsid(struct task_struct *p)
3393 {
3394         return current_has_perm(p, PROCESS__GETSESSION);
3395 }
3396
3397 static void selinux_task_getsecid(struct task_struct *p, u32 *secid)
3398 {
3399         *secid = task_sid(p);
3400 }
3401
3402 static int selinux_task_setgroups(struct group_info *group_info)
3403 {
3404         /* See the comment for setuid above. */
3405         return 0;
3406 }
3407
3408 static int selinux_task_setnice(struct task_struct *p, int nice)
3409 {
3410         int rc;
3411
3412         rc = secondary_ops->task_setnice(p, nice);
3413         if (rc)
3414                 return rc;
3415
3416         return current_has_perm(p, PROCESS__SETSCHED);
3417 }
3418
3419 static int selinux_task_setioprio(struct task_struct *p, int ioprio)
3420 {
3421         int rc;
3422
3423         rc = secondary_ops->task_setioprio(p, ioprio);
3424         if (rc)
3425                 return rc;
3426
3427         return current_has_perm(p, PROCESS__SETSCHED);
3428 }
3429
3430 static int selinux_task_getioprio(struct task_struct *p)
3431 {
3432         return current_has_perm(p, PROCESS__GETSCHED);
3433 }
3434
3435 static int selinux_task_setrlimit(unsigned int resource, struct rlimit *new_rlim)
3436 {
3437         struct rlimit *old_rlim = current->signal->rlim + resource;
3438         int rc;
3439
3440         rc = secondary_ops->task_setrlimit(resource, new_rlim);
3441         if (rc)
3442                 return rc;
3443
3444         /* Control the ability to change the hard limit (whether
3445            lowering or raising it), so that the hard limit can
3446            later be used as a safe reset point for the soft limit
3447            upon context transitions.  See selinux_bprm_committing_creds. */
3448         if (old_rlim->rlim_max != new_rlim->rlim_max)
3449                 return current_has_perm(current, PROCESS__SETRLIMIT);
3450
3451         return 0;
3452 }
3453
3454 static int selinux_task_setscheduler(struct task_struct *p, int policy, struct sched_param *lp)
3455 {
3456         int rc;
3457
3458         rc = secondary_ops->task_setscheduler(p, policy, lp);
3459         if (rc)
3460                 return rc;
3461
3462         return current_has_perm(p, PROCESS__SETSCHED);
3463 }
3464
3465 static int selinux_task_getscheduler(struct task_struct *p)
3466 {
3467         return current_has_perm(p, PROCESS__GETSCHED);
3468 }
3469
3470 static int selinux_task_movememory(struct task_struct *p)
3471 {
3472         return current_has_perm(p, PROCESS__SETSCHED);
3473 }
3474
3475 static int selinux_task_kill(struct task_struct *p, struct siginfo *info,
3476                                 int sig, u32 secid)
3477 {
3478         u32 perm;
3479         int rc;
3480
3481         rc = secondary_ops->task_kill(p, info, sig, secid);
3482         if (rc)
3483                 return rc;
3484
3485         if (!sig)
3486                 perm = PROCESS__SIGNULL; /* null signal; existence test */
3487         else
3488                 perm = signal_to_av(sig);
3489         if (secid)
3490                 rc = avc_has_perm(secid, task_sid(p),
3491                                   SECCLASS_PROCESS, perm, NULL);
3492         else
3493                 rc = current_has_perm(p, perm);
3494         return rc;
3495 }
3496
3497 static int selinux_task_prctl(int option,
3498                               unsigned long arg2,
3499                               unsigned long arg3,
3500                               unsigned long arg4,
3501                               unsigned long arg5)
3502 {
3503         /* The current prctl operations do not appear to require
3504            any SELinux controls since they merely observe or modify
3505            the state of the current process. */
3506         return secondary_ops->task_prctl(option, arg2, arg3, arg4, arg5);
3507 }
3508
3509 static int selinux_task_wait(struct task_struct *p)
3510 {
3511         return task_has_perm(p, current, PROCESS__SIGCHLD);
3512 }
3513
3514 static void selinux_task_to_inode(struct task_struct *p,
3515                                   struct inode *inode)
3516 {
3517         struct inode_security_struct *isec = inode->i_security;
3518         u32 sid = task_sid(p);
3519
3520         isec->sid = sid;
3521         isec->initialized = 1;
3522 }
3523
3524 /* Returns error only if unable to parse addresses */
3525 static int selinux_parse_skb_ipv4(struct sk_buff *skb,
3526                         struct avc_audit_data *ad, u8 *proto)
3527 {
3528         int offset, ihlen, ret = -EINVAL;
3529         struct iphdr _iph, *ih;
3530
3531         offset = skb_network_offset(skb);
3532         ih = skb_header_pointer(skb, offset, sizeof(_iph), &_iph);
3533         if (ih == NULL)
3534                 goto out;
3535
3536         ihlen = ih->ihl * 4;
3537         if (ihlen < sizeof(_iph))
3538                 goto out;
3539
3540         ad->u.net.v4info.saddr = ih->saddr;
3541         ad->u.net.v4info.daddr = ih->daddr;
3542         ret = 0;
3543
3544         if (proto)
3545                 *proto = ih->protocol;
3546
3547         switch (ih->protocol) {
3548         case IPPROTO_TCP: {
3549                 struct tcphdr _tcph, *th;
3550
3551                 if (ntohs(ih->frag_off) & IP_OFFSET)
3552                         break;
3553
3554                 offset += ihlen;
3555                 th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph);
3556                 if (th == NULL)
3557                         break;
3558
3559                 ad->u.net.sport = th->source;
3560                 ad->u.net.dport = th->dest;
3561                 break;
3562         }
3563
3564         case IPPROTO_UDP: {
3565                 struct udphdr _udph, *uh;
3566
3567                 if (ntohs(ih->frag_off) & IP_OFFSET)
3568                         break;
3569
3570                 offset += ihlen;
3571                 uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph);
3572                 if (uh == NULL)
3573                         break;
3574
3575                 ad->u.net.sport = uh->source;
3576                 ad->u.net.dport = uh->dest;
3577                 break;
3578         }
3579
3580         case IPPROTO_DCCP: {
3581                 struct dccp_hdr _dccph, *dh;
3582
3583                 if (ntohs(ih->frag_off) & IP_OFFSET)
3584                         break;
3585
3586                 offset += ihlen;
3587                 dh = skb_header_pointer(skb, offset, sizeof(_dccph), &_dccph);
3588                 if (dh == NULL)
3589                         break;
3590
3591                 ad->u.net.sport = dh->dccph_sport;
3592                 ad->u.net.dport = dh->dccph_dport;
3593                 break;
3594         }
3595
3596         default:
3597                 break;
3598         }
3599 out:
3600         return ret;
3601 }
3602
3603 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
3604
3605 /* Returns error only if unable to parse addresses */
3606 static int selinux_parse_skb_ipv6(struct sk_buff *skb,
3607                         struct avc_audit_data *ad, u8 *proto)
3608 {
3609         u8 nexthdr;
3610         int ret = -EINVAL, offset;
3611         struct ipv6hdr _ipv6h, *ip6;
3612
3613         offset = skb_network_offset(skb);
3614         ip6 = skb_header_pointer(skb, offset, sizeof(_ipv6h), &_ipv6h);
3615         if (ip6 == NULL)
3616                 goto out;
3617
3618         ipv6_addr_copy(&ad->u.net.v6info.saddr, &ip6->saddr);
3619         ipv6_addr_copy(&ad->u.net.v6info.daddr, &ip6->daddr);
3620         ret = 0;
3621
3622         nexthdr = ip6->nexthdr;
3623         offset += sizeof(_ipv6h);
3624         offset = ipv6_skip_exthdr(skb, offset, &nexthdr);
3625         if (offset < 0)
3626                 goto out;
3627
3628         if (proto)
3629                 *proto = nexthdr;
3630
3631         switch (nexthdr) {
3632         case IPPROTO_TCP: {
3633                 struct tcphdr _tcph, *th;
3634
3635                 th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph);
3636                 if (th == NULL)
3637                         break;
3638
3639                 ad->u.net.sport = th->source;
3640                 ad->u.net.dport = th->dest;
3641                 break;
3642         }
3643
3644         case IPPROTO_UDP: {
3645                 struct udphdr _udph, *uh;
3646
3647                 uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph);
3648                 if (uh == NULL)
3649                         break;
3650
3651                 ad->u.net.sport = uh->source;
3652                 ad->u.net.dport = uh->dest;
3653                 break;
3654         }
3655
3656         case IPPROTO_DCCP: {
3657                 struct dccp_hdr _dccph, *dh;
3658
3659                 dh = skb_header_pointer(skb, offset, sizeof(_dccph), &_dccph);
3660                 if (dh == NULL)
3661                         break;
3662
3663                 ad->u.net.sport = dh->dccph_sport;
3664                 ad->u.net.dport = dh->dccph_dport;
3665                 break;
3666         }
3667
3668         /* includes fragments */
3669         default:
3670                 break;
3671         }
3672 out:
3673         return ret;
3674 }
3675
3676 #endif /* IPV6 */
3677
3678 static int selinux_parse_skb(struct sk_buff *skb, struct avc_audit_data *ad,
3679                              char **_addrp, int src, u8 *proto)
3680 {
3681         char *addrp;
3682         int ret;
3683
3684         switch (ad->u.net.family) {
3685         case PF_INET:
3686                 ret = selinux_parse_skb_ipv4(skb, ad, proto);
3687                 if (ret)
3688                         goto parse_error;
3689                 addrp = (char *)(src ? &ad->u.net.v4info.saddr :
3690                                        &ad->u.net.v4info.daddr);
3691                 goto okay;
3692
3693 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
3694         case PF_INET6:
3695                 ret = selinux_parse_skb_ipv6(skb, ad, proto);
3696                 if (ret)
3697                         goto parse_error;
3698                 addrp = (char *)(src ? &ad->u.net.v6info.saddr :
3699                                        &ad->u.net.v6info.daddr);
3700                 goto okay;
3701 #endif  /* IPV6 */
3702         default:
3703                 addrp = NULL;
3704                 goto okay;
3705         }
3706
3707 parse_error:
3708         printk(KERN_WARNING
3709                "SELinux: failure in selinux_parse_skb(),"
3710                " unable to parse packet\n");
3711         return ret;
3712
3713 okay:
3714         if (_addrp)
3715                 *_addrp = addrp;
3716         return 0;
3717 }
3718
3719 /**
3720  * selinux_skb_peerlbl_sid - Determine the peer label of a packet
3721  * @skb: the packet
3722  * @family: protocol family
3723  * @sid: the packet's peer label SID
3724  *
3725  * Description:
3726  * Check the various different forms of network peer labeling and determine
3727  * the peer label/SID for the packet; most of the magic actually occurs in
3728  * the security server function security_net_peersid_cmp().  The function
3729  * returns zero if the value in @sid is valid (although it may be SECSID_NULL)
3730  * or -EACCES if @sid is invalid due to inconsistencies with the different
3731  * peer labels.
3732  *
3733  */
3734 static int selinux_skb_peerlbl_sid(struct sk_buff *skb, u16 family, u32 *sid)
3735 {
3736         int err;
3737         u32 xfrm_sid;
3738         u32 nlbl_sid;
3739         u32 nlbl_type;
3740
3741         selinux_skb_xfrm_sid(skb, &xfrm_sid);
3742         selinux_netlbl_skbuff_getsid(skb, family, &nlbl_type, &nlbl_sid);
3743
3744         err = security_net_peersid_resolve(nlbl_sid, nlbl_type, xfrm_sid, sid);
3745         if (unlikely(err)) {
3746                 printk(KERN_WARNING
3747                        "SELinux: failure in selinux_skb_peerlbl_sid(),"
3748                        " unable to determine packet's peer label\n");
3749                 return -EACCES;
3750         }
3751
3752         return 0;
3753 }
3754
3755 /* socket security operations */
3756 static int socket_has_perm(struct task_struct *task, struct socket *sock,
3757                            u32 perms)
3758 {
3759         struct inode_security_struct *isec;
3760         struct avc_audit_data ad;
3761         u32 sid;
3762         int err = 0;
3763
3764         isec = SOCK_INODE(sock)->i_security;
3765
3766         if (isec->sid == SECINITSID_KERNEL)
3767                 goto out;
3768         sid = task_sid(task);
3769
3770         AVC_AUDIT_DATA_INIT(&ad, NET);
3771         ad.u.net.sk = sock->sk;
3772         err = avc_has_perm(sid, isec->sid, isec->sclass, perms, &ad);
3773
3774 out:
3775         return err;
3776 }
3777
3778 static int selinux_socket_create(int family, int type,
3779                                  int protocol, int kern)
3780 {
3781         const struct cred *cred = current_cred();
3782         const struct task_security_struct *tsec = cred->security;
3783         u32 sid, newsid;
3784         u16 secclass;
3785         int err = 0;
3786
3787         if (kern)
3788                 goto out;
3789
3790         sid = tsec->sid;
3791         newsid = tsec->sockcreate_sid ?: sid;
3792
3793         secclass = socket_type_to_security_class(family, type, protocol);
3794         err = avc_has_perm(sid, newsid, secclass, SOCKET__CREATE, NULL);
3795
3796 out:
3797         return err;
3798 }
3799
3800 static int selinux_socket_post_create(struct socket *sock, int family,
3801                                       int type, int protocol, int kern)
3802 {
3803         const struct cred *cred = current_cred();
3804         const struct task_security_struct *tsec = cred->security;
3805         struct inode_security_struct *isec;
3806         struct sk_security_struct *sksec;
3807         u32 sid, newsid;
3808         int err = 0;
3809
3810         sid = tsec->sid;
3811         newsid = tsec->sockcreate_sid;
3812
3813         isec = SOCK_INODE(sock)->i_security;
3814
3815         if (kern)
3816                 isec->sid = SECINITSID_KERNEL;
3817         else if (newsid)
3818                 isec->sid = newsid;
3819         else
3820                 isec->sid = sid;
3821
3822         isec->sclass = socket_type_to_security_class(family, type, protocol);
3823         isec->initialized = 1;
3824
3825         if (sock->sk) {
3826                 sksec = sock->sk->sk_security;
3827                 sksec->sid = isec->sid;
3828                 sksec->sclass = isec->sclass;
3829                 err = selinux_netlbl_socket_post_create(sock);
3830         }
3831
3832         return err;
3833 }
3834
3835 /* Range of port numbers used to automatically bind.
3836    Need to determine whether we should perform a name_bind
3837    permission check between the socket and the port number. */
3838
3839 static int selinux_socket_bind(struct socket *sock, struct sockaddr *address, int addrlen)
3840 {
3841         u16 family;
3842         int err;
3843
3844         err = socket_has_perm(current, sock, SOCKET__BIND);
3845         if (err)
3846                 goto out;
3847
3848         /*
3849          * If PF_INET or PF_INET6, check name_bind permission for the port.
3850          * Multiple address binding for SCTP is not supported yet: we just
3851          * check the first address now.
3852          */
3853         family = sock->sk->sk_family;
3854         if (family == PF_INET || family == PF_INET6) {
3855                 char *addrp;
3856                 struct inode_security_struct *isec;
3857                 struct avc_audit_data ad;
3858                 struct sockaddr_in *addr4 = NULL;
3859                 struct sockaddr_in6 *addr6 = NULL;
3860                 unsigned short snum;
3861                 struct sock *sk = sock->sk;
3862                 u32 sid, node_perm;
3863
3864                 isec = SOCK_INODE(sock)->i_security;
3865
3866                 if (family == PF_INET) {
3867                         addr4 = (struct sockaddr_in *)address;
3868                         snum = ntohs(addr4->sin_port);
3869                         addrp = (char *)&addr4->sin_addr.s_addr;
3870                 } else {
3871                         addr6 = (struct sockaddr_in6 *)address;
3872                         snum = ntohs(addr6->sin6_port);
3873                         addrp = (char *)&addr6->sin6_addr.s6_addr;
3874                 }
3875
3876                 if (snum) {
3877                         int low, high;
3878
3879                         inet_get_local_port_range(&low, &high);
3880
3881                         if (snum < max(PROT_SOCK, low) || snum > high) {
3882                                 err = sel_netport_sid(sk->sk_protocol,
3883                                                       snum, &sid);
3884                                 if (err)
3885                                         goto out;
3886                                 AVC_AUDIT_DATA_INIT(&ad, NET);
3887                                 ad.u.net.sport = htons(snum);
3888                                 ad.u.net.family = family;
3889                                 err = avc_has_perm(isec->sid, sid,
3890                                                    isec->sclass,
3891                                                    SOCKET__NAME_BIND, &ad);
3892                                 if (err)
3893                                         goto out;
3894                         }
3895                 }
3896
3897                 switch (isec->sclass) {
3898                 case SECCLASS_TCP_SOCKET:
3899                         node_perm = TCP_SOCKET__NODE_BIND;
3900                         break;
3901
3902                 case SECCLASS_UDP_SOCKET:
3903                         node_perm = UDP_SOCKET__NODE_BIND;
3904                         break;
3905
3906                 case SECCLASS_DCCP_SOCKET:
3907                         node_perm = DCCP_SOCKET__NODE_BIND;
3908                         break;
3909
3910                 default:
3911                         node_perm = RAWIP_SOCKET__NODE_BIND;
3912                         break;
3913                 }
3914
3915                 err = sel_netnode_sid(addrp, family, &sid);
3916                 if (err)
3917                         goto out;
3918
3919                 AVC_AUDIT_DATA_INIT(&ad, NET);
3920                 ad.u.net.sport = htons(snum);
3921                 ad.u.net.family = family;
3922
3923                 if (family == PF_INET)
3924                         ad.u.net.v4info.saddr = addr4->sin_addr.s_addr;
3925                 else
3926                         ipv6_addr_copy(&ad.u.net.v6info.saddr, &addr6->sin6_addr);
3927
3928                 err = avc_has_perm(isec->sid, sid,
3929                                    isec->sclass, node_perm, &ad);
3930                 if (err)
3931                         goto out;
3932         }
3933 out:
3934         return err;
3935 }
3936
3937 static int selinux_socket_connect(struct socket *sock, struct sockaddr *address, int addrlen)
3938 {
3939         struct sock *sk = sock->sk;
3940         struct inode_security_struct *isec;
3941         int err;
3942
3943         err = socket_has_perm(current, sock, SOCKET__CONNECT);
3944         if (err)
3945                 return err;
3946
3947         /*
3948          * If a TCP or DCCP socket, check name_connect permission for the port.
3949          */
3950         isec = SOCK_INODE(sock)->i_security;
3951         if (isec->sclass == SECCLASS_TCP_SOCKET ||
3952             isec->sclass == SECCLASS_DCCP_SOCKET) {
3953                 struct avc_audit_data ad;
3954                 struct sockaddr_in *addr4 = NULL;
3955                 struct sockaddr_in6 *addr6 = NULL;
3956                 unsigned short snum;
3957                 u32 sid, perm;
3958
3959                 if (sk->sk_family == PF_INET) {
3960                         addr4 = (struct sockaddr_in *)address;
3961                         if (addrlen < sizeof(struct sockaddr_in))
3962                                 return -EINVAL;
3963                         snum = ntohs(addr4->sin_port);
3964                 } else {
3965                         addr6 = (struct sockaddr_in6 *)address;
3966                         if (addrlen < SIN6_LEN_RFC2133)
3967                                 return -EINVAL;
3968                         snum = ntohs(addr6->sin6_port);
3969                 }
3970
3971                 err = sel_netport_sid(sk->sk_protocol, snum, &sid);
3972                 if (err)
3973                         goto out;
3974
3975                 perm = (isec->sclass == SECCLASS_TCP_SOCKET) ?
3976                        TCP_SOCKET__NAME_CONNECT : DCCP_SOCKET__NAME_CONNECT;
3977
3978                 AVC_AUDIT_DATA_INIT(&ad, NET);
3979                 ad.u.net.dport = htons(snum);
3980                 ad.u.net.family = sk->sk_family;
3981                 err = avc_has_perm(isec->sid, sid, isec->sclass, perm, &ad);
3982                 if (err)
3983                         goto out;
3984         }
3985
3986         err = selinux_netlbl_socket_connect(sk, address);
3987
3988 out:
3989         return err;
3990 }
3991
3992 static int selinux_socket_listen(struct socket *sock, int backlog)
3993 {
3994         return socket_has_perm(current, sock, SOCKET__LISTEN);
3995 }
3996
3997 static int selinux_socket_accept(struct socket *sock, struct socket *newsock)
3998 {
3999         int err;
4000         struct inode_security_struct *isec;
4001         struct inode_security_struct *newisec;
4002
4003         err = socket_has_perm(current, sock, SOCKET__ACCEPT);
4004         if (err)
4005                 return err;
4006
4007         newisec = SOCK_INODE(newsock)->i_security;
4008
4009         isec = SOCK_INODE(sock)->i_security;
4010         newisec->sclass = isec->sclass;
4011         newisec->sid = isec->sid;
4012         newisec->initialized = 1;
4013
4014         return 0;
4015 }
4016
4017 static int selinux_socket_sendmsg(struct socket *sock, struct msghdr *msg,
4018                                   int size)
4019 {
4020         int rc;
4021
4022         rc = socket_has_perm(current, sock, SOCKET__WRITE);
4023         if (rc)
4024                 return rc;
4025
4026         return selinux_netlbl_inode_permission(SOCK_INODE(sock), MAY_WRITE);
4027 }
4028
4029 static int selinux_socket_recvmsg(struct socket *sock, struct msghdr *msg,
4030                                   int size, int flags)
4031 {
4032         return socket_has_perm(current, sock, SOCKET__READ);
4033 }
4034
4035 static int selinux_socket_getsockname(struct socket *sock)
4036 {
4037         return socket_has_perm(current, sock, SOCKET__GETATTR);
4038 }
4039
4040 static int selinux_socket_getpeername(struct socket *sock)
4041 {
4042         return socket_has_perm(current, sock, SOCKET__GETATTR);
4043 }
4044
4045 static int selinux_socket_setsockopt(struct socket *sock, int level, int optname)
4046 {
4047         int err;
4048
4049         err = socket_has_perm(current, sock, SOCKET__SETOPT);
4050         if (err)
4051                 return err;
4052
4053         return selinux_netlbl_socket_setsockopt(sock, level, optname);
4054 }
4055
4056 static int selinux_socket_getsockopt(struct socket *sock, int level,
4057                                      int optname)
4058 {
4059         return socket_has_perm(current, sock, SOCKET__GETOPT);
4060 }
4061
4062 static int selinux_socket_shutdown(struct socket *sock, int how)
4063 {
4064         return socket_has_perm(current, sock, SOCKET__SHUTDOWN);
4065 }
4066
4067 static int selinux_socket_unix_stream_connect(struct socket *sock,
4068                                               struct socket *other,
4069                                               struct sock *newsk)
4070 {
4071         struct sk_security_struct *ssec;
4072         struct inode_security_struct *isec;
4073         struct inode_security_struct *other_isec;
4074         struct avc_audit_data ad;
4075         int err;
4076
4077         err = secondary_ops->unix_stream_connect(sock, other, newsk);
4078         if (err)
4079                 return err;
4080
4081         isec = SOCK_INODE(sock)->i_security;
4082         other_isec = SOCK_INODE(other)->i_security;
4083
4084         AVC_AUDIT_DATA_INIT(&ad, NET);
4085         ad.u.net.sk = other->sk;
4086
4087         err = avc_has_perm(isec->sid, other_isec->sid,
4088                            isec->sclass,
4089                            UNIX_STREAM_SOCKET__CONNECTTO, &ad);
4090         if (err)
4091                 return err;
4092
4093         /* connecting socket */
4094         ssec = sock->sk->sk_security;
4095         ssec->peer_sid = other_isec->sid;
4096
4097         /* server child socket */
4098         ssec = newsk->sk_security;
4099         ssec->peer_sid = isec->sid;
4100         err = security_sid_mls_copy(other_isec->sid, ssec->peer_sid, &ssec->sid);
4101
4102         return err;
4103 }
4104
4105 static int selinux_socket_unix_may_send(struct socket *sock,
4106                                         struct socket *other)
4107 {
4108         struct inode_security_struct *isec;
4109         struct inode_security_struct *other_isec;
4110         struct avc_audit_data ad;
4111         int err;
4112
4113         isec = SOCK_INODE(sock)->i_security;
4114         other_isec = SOCK_INODE(other)->i_security;
4115
4116         AVC_AUDIT_DATA_INIT(&ad, NET);
4117         ad.u.net.sk = other->sk;
4118
4119         err = avc_has_perm(isec->sid, other_isec->sid,
4120                            isec->sclass, SOCKET__SENDTO, &ad);
4121         if (err)
4122                 return err;
4123
4124         return 0;
4125 }
4126
4127 static int selinux_inet_sys_rcv_skb(int ifindex, char *addrp, u16 family,
4128                                     u32 peer_sid,
4129                                     struct avc_audit_data *ad)
4130 {
4131         int err;
4132         u32 if_sid;
4133         u32 node_sid;
4134
4135         err = sel_netif_sid(ifindex, &if_sid);
4136         if (err)
4137                 return err;
4138         err = avc_has_perm(peer_sid, if_sid,
4139                            SECCLASS_NETIF, NETIF__INGRESS, ad);
4140         if (err)
4141                 return err;
4142
4143         err = sel_netnode_sid(addrp, family, &node_sid);
4144         if (err)
4145                 return err;
4146         return avc_has_perm(peer_sid, node_sid,
4147                             SECCLASS_NODE, NODE__RECVFROM, ad);
4148 }
4149
4150 static int selinux_sock_rcv_skb_iptables_compat(struct sock *sk,
4151                                                 struct sk_buff *skb,
4152                                                 struct avc_audit_data *ad,
4153                                                 u16 family,
4154                                                 char *addrp)
4155 {
4156         int err;
4157         struct sk_security_struct *sksec = sk->sk_security;
4158         u16 sk_class;
4159         u32 netif_perm, node_perm, recv_perm;
4160         u32 port_sid, node_sid, if_sid, sk_sid;
4161
4162         sk_sid = sksec->sid;
4163         sk_class = sksec->sclass;
4164
4165         switch (sk_class) {
4166         case SECCLASS_UDP_SOCKET:
4167                 netif_perm = NETIF__UDP_RECV;
4168                 node_perm = NODE__UDP_RECV;
4169                 recv_perm = UDP_SOCKET__RECV_MSG;
4170                 break;
4171         case SECCLASS_TCP_SOCKET:
4172                 netif_perm = NETIF__TCP_RECV;
4173                 node_perm = NODE__TCP_RECV;
4174                 recv_perm = TCP_SOCKET__RECV_MSG;
4175                 break;
4176         case SECCLASS_DCCP_SOCKET:
4177                 netif_perm = NETIF__DCCP_RECV;
4178                 node_perm = NODE__DCCP_RECV;
4179                 recv_perm = DCCP_SOCKET__RECV_MSG;
4180                 break;
4181         default:
4182                 netif_perm = NETIF__RAWIP_RECV;
4183                 node_perm = NODE__RAWIP_RECV;
4184                 recv_perm = 0;
4185                 break;
4186         }
4187
4188         err = sel_netif_sid(skb->iif, &if_sid);
4189         if (err)
4190                 return err;
4191         err = avc_has_perm(sk_sid, if_sid, SECCLASS_NETIF, netif_perm, ad);
4192         if (err)
4193                 return err;
4194
4195         err = sel_netnode_sid(addrp, family, &node_sid);
4196         if (err)
4197                 return err;
4198         err = avc_has_perm(sk_sid, node_sid, SECCLASS_NODE, node_perm, ad);
4199         if (err)
4200                 return err;
4201
4202         if (!recv_perm)
4203                 return 0;
4204         err = sel_netport_sid(sk->sk_protocol,
4205                               ntohs(ad->u.net.sport), &port_sid);
4206         if (unlikely(err)) {
4207                 printk(KERN_WARNING
4208                        "SELinux: failure in"
4209                        " selinux_sock_rcv_skb_iptables_compat(),"
4210                        " network port label not found\n");
4211                 return err;
4212         }
4213         return avc_has_perm(sk_sid, port_sid, sk_class, recv_perm, ad);
4214 }
4215
4216 static int selinux_sock_rcv_skb_compat(struct sock *sk, struct sk_buff *skb,
4217                                        u16 family)
4218 {
4219         int err = 0;
4220         struct sk_security_struct *sksec = sk->sk_security;
4221         u32 peer_sid;
4222         u32 sk_sid = sksec->sid;
4223         struct avc_audit_data ad;
4224         char *addrp;
4225
4226         AVC_AUDIT_DATA_INIT(&ad, NET);
4227         ad.u.net.netif = skb->iif;
4228         ad.u.net.family = family;
4229         err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL);
4230         if (err)
4231                 return err;
4232
4233         if (selinux_compat_net)
4234                 err = selinux_sock_rcv_skb_iptables_compat(sk, skb, &ad,
4235                                                            family, addrp);
4236         else if (selinux_secmark_enabled())
4237                 err = avc_has_perm(sk_sid, skb->secmark, SECCLASS_PACKET,
4238                                    PACKET__RECV, &ad);
4239         if (err)
4240                 return err;
4241
4242         if (selinux_policycap_netpeer) {
4243                 err = selinux_skb_peerlbl_sid(skb, family, &peer_sid);
4244                 if (err)
4245                         return err;
4246                 err = avc_has_perm(sk_sid, peer_sid,
4247                                    SECCLASS_PEER, PEER__RECV, &ad);
4248                 if (err)
4249                         selinux_netlbl_err(skb, err, 0);
4250         } else {
4251                 err = selinux_netlbl_sock_rcv_skb(sksec, skb, family, &ad);
4252                 if (err)
4253                         return err;
4254                 err = selinux_xfrm_sock_rcv_skb(sksec->sid, skb, &ad);
4255         }
4256
4257         return err;
4258 }
4259
4260 static int selinux_socket_sock_rcv_skb(struct sock *sk, struct sk_buff *skb)
4261 {
4262         int err;
4263         struct sk_security_struct *sksec = sk->sk_security;
4264         u16 family = sk->sk_family;
4265         u32 sk_sid = sksec->sid;
4266         struct avc_audit_data ad;
4267         char *addrp;
4268         u8 secmark_active;
4269         u8 peerlbl_active;
4270
4271         if (family != PF_INET && family != PF_INET6)
4272                 return 0;
4273
4274         /* Handle mapped IPv4 packets arriving via IPv6 sockets */
4275         if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
4276                 family = PF_INET;
4277
4278         /* If any sort of compatibility mode is enabled then handoff processing
4279          * to the selinux_sock_rcv_skb_compat() function to deal with the
4280          * special handling.  We do this in an attempt to keep this function
4281          * as fast and as clean as possible. */
4282         if (selinux_compat_net || !selinux_policycap_netpeer)
4283                 return selinux_sock_rcv_skb_compat(sk, skb, family);
4284
4285         secmark_active = selinux_secmark_enabled();
4286         peerlbl_active = netlbl_enabled() || selinux_xfrm_enabled();
4287         if (!secmark_active && !peerlbl_active)
4288                 return 0;
4289
4290         AVC_AUDIT_DATA_INIT(&ad, NET);
4291         ad.u.net.netif = skb->iif;
4292         ad.u.net.family = family;
4293         err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL);
4294         if (err)
4295                 return err;
4296
4297         if (peerlbl_active) {
4298                 u32 peer_sid;
4299
4300                 err = selinux_skb_peerlbl_sid(skb, family, &peer_sid);
4301                 if (err)
4302                         return err;
4303                 err = selinux_inet_sys_rcv_skb(skb->iif, addrp, family,
4304                                                peer_sid, &ad);
4305                 if (err) {
4306                         selinux_netlbl_err(skb, err, 0);
4307                         return err;
4308                 }
4309                 err = avc_has_perm(sk_sid, peer_sid, SECCLASS_PEER,
4310                                    PEER__RECV, &ad);
4311                 if (err)
4312                         selinux_netlbl_err(skb, err, 0);
4313         }
4314
4315         if (secmark_active) {
4316                 err = avc_has_perm(sk_sid, skb->secmark, SECCLASS_PACKET,
4317                                    PACKET__RECV, &ad);
4318                 if (err)
4319                         return err;
4320         }
4321
4322         return err;
4323 }
4324
4325 static int selinux_socket_getpeersec_stream(struct socket *sock, char __user *optval,
4326                                             int __user *optlen, unsigned len)
4327 {
4328         int err = 0;
4329         char *scontext;
4330         u32 scontext_len;
4331         struct sk_security_struct *ssec;
4332         struct inode_security_struct *isec;
4333         u32 peer_sid = SECSID_NULL;
4334
4335         isec = SOCK_INODE(sock)->i_security;
4336
4337         if (isec->sclass == SECCLASS_UNIX_STREAM_SOCKET ||
4338             isec->sclass == SECCLASS_TCP_SOCKET) {
4339                 ssec = sock->sk->sk_security;
4340                 peer_sid = ssec->peer_sid;
4341         }
4342         if (peer_sid == SECSID_NULL) {
4343                 err = -ENOPROTOOPT;
4344                 goto out;
4345         }
4346
4347         err = security_sid_to_context(peer_sid, &scontext, &scontext_len);
4348
4349         if (err)
4350                 goto out;
4351
4352         if (scontext_len > len) {
4353                 err = -ERANGE;
4354                 goto out_len;
4355         }
4356
4357         if (copy_to_user(optval, scontext, scontext_len))
4358                 err = -EFAULT;
4359
4360 out_len:
4361         if (put_user(scontext_len, optlen))
4362                 err = -EFAULT;
4363
4364         kfree(scontext);
4365 out:
4366         return err;
4367 }
4368
4369 static int selinux_socket_getpeersec_dgram(struct socket *sock, struct sk_buff *skb, u32 *secid)
4370 {
4371         u32 peer_secid = SECSID_NULL;
4372         u16 family;
4373
4374         if (skb && skb->protocol == htons(ETH_P_IP))
4375                 family = PF_INET;
4376         else if (skb && skb->protocol == htons(ETH_P_IPV6))
4377                 family = PF_INET6;
4378         else if (sock)
4379                 family = sock->sk->sk_family;
4380         else
4381                 goto out;
4382
4383         if (sock && family == PF_UNIX)
4384                 selinux_inode_getsecid(SOCK_INODE(sock), &peer_secid);
4385         else if (skb)
4386                 selinux_skb_peerlbl_sid(skb, family, &peer_secid);
4387
4388 out:
4389         *secid = peer_secid;
4390         if (peer_secid == SECSID_NULL)
4391                 return -EINVAL;
4392         return 0;
4393 }
4394
4395 static int selinux_sk_alloc_security(struct sock *sk, int family, gfp_t priority)
4396 {
4397         return sk_alloc_security(sk, family, priority);
4398 }
4399
4400 static void selinux_sk_free_security(struct sock *sk)
4401 {
4402         sk_free_security(sk);
4403 }
4404
4405 static void selinux_sk_clone_security(const struct sock *sk, struct sock *newsk)
4406 {
4407         struct sk_security_struct *ssec = sk->sk_security;
4408         struct sk_security_struct *newssec = newsk->sk_security;
4409
4410         newssec->sid = ssec->sid;
4411         newssec->peer_sid = ssec->peer_sid;
4412         newssec->sclass = ssec->sclass;
4413
4414         selinux_netlbl_sk_security_reset(newssec, newsk->sk_family);
4415 }
4416
4417 static void selinux_sk_getsecid(struct sock *sk, u32 *secid)
4418 {
4419         if (!sk)
4420                 *secid = SECINITSID_ANY_SOCKET;
4421         else {
4422                 struct sk_security_struct *sksec = sk->sk_security;
4423
4424                 *secid = sksec->sid;
4425         }
4426 }
4427
4428 static void selinux_sock_graft(struct sock *sk, struct socket *parent)
4429 {
4430         struct inode_security_struct *isec = SOCK_INODE(parent)->i_security;
4431         struct sk_security_struct *sksec = sk->sk_security;
4432
4433         if (sk->sk_family == PF_INET || sk->sk_family == PF_INET6 ||
4434             sk->sk_family == PF_UNIX)
4435                 isec->sid = sksec->sid;
4436         sksec->sclass = isec->sclass;
4437 }
4438
4439 static int selinux_inet_conn_request(struct sock *sk, struct sk_buff *skb,
4440                                      struct request_sock *req)
4441 {
4442         struct sk_security_struct *sksec = sk->sk_security;
4443         int err;
4444         u16 family = sk->sk_family;
4445         u32 newsid;
4446         u32 peersid;
4447
4448         /* handle mapped IPv4 packets arriving via IPv6 sockets */
4449         if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
4450                 family = PF_INET;
4451
4452         err = selinux_skb_peerlbl_sid(skb, family, &peersid);
4453         if (err)
4454                 return err;
4455         if (peersid == SECSID_NULL) {
4456                 req->secid = sksec->sid;
4457                 req->peer_secid = SECSID_NULL;
4458                 return 0;
4459         }
4460
4461         err = security_sid_mls_copy(sksec->sid, peersid, &newsid);
4462         if (err)
4463                 return err;
4464
4465         req->secid = newsid;
4466         req->peer_secid = peersid;
4467         return 0;
4468 }
4469
4470 static void selinux_inet_csk_clone(struct sock *newsk,
4471                                    const struct request_sock *req)
4472 {
4473         struct sk_security_struct *newsksec = newsk->sk_security;
4474
4475         newsksec->sid = req->secid;
4476         newsksec->peer_sid = req->peer_secid;
4477         /* NOTE: Ideally, we should also get the isec->sid for the
4478            new socket in sync, but we don't have the isec available yet.
4479            So we will wait until sock_graft to do it, by which
4480            time it will have been created and available. */
4481
4482         /* We don't need to take any sort of lock here as we are the only
4483          * thread with access to newsksec */
4484         selinux_netlbl_sk_security_reset(newsksec, req->rsk_ops->family);
4485 }
4486
4487 static void selinux_inet_conn_established(struct sock *sk, struct sk_buff *skb)
4488 {
4489         u16 family = sk->sk_family;
4490         struct sk_security_struct *sksec = sk->sk_security;
4491
4492         /* handle mapped IPv4 packets arriving via IPv6 sockets */
4493         if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
4494                 family = PF_INET;
4495
4496         selinux_skb_peerlbl_sid(skb, family, &sksec->peer_sid);
4497
4498         selinux_netlbl_inet_conn_established(sk, family);
4499 }
4500
4501 static void selinux_req_classify_flow(const struct request_sock *req,
4502                                       struct flowi *fl)
4503 {
4504         fl->secid = req->secid;
4505 }
4506
4507 static int selinux_nlmsg_perm(struct sock *sk, struct sk_buff *skb)
4508 {
4509         int err = 0;
4510         u32 perm;
4511         struct nlmsghdr *nlh;
4512         struct socket *sock = sk->sk_socket;
4513         struct inode_security_struct *isec = SOCK_INODE(sock)->i_security;
4514
4515         if (skb->len < NLMSG_SPACE(0)) {
4516                 err = -EINVAL;
4517                 goto out;
4518         }
4519         nlh = nlmsg_hdr(skb);
4520
4521         err = selinux_nlmsg_lookup(isec->sclass, nlh->nlmsg_type, &perm);
4522         if (err) {
4523                 if (err == -EINVAL) {
4524                         audit_log(current->audit_context, GFP_KERNEL, AUDIT_SELINUX_ERR,
4525                                   "SELinux:  unrecognized netlink message"
4526                                   " type=%hu for sclass=%hu\n",
4527                                   nlh->nlmsg_type, isec->sclass);
4528                         if (!selinux_enforcing || security_get_allow_unknown())
4529                                 err = 0;
4530                 }
4531
4532                 /* Ignore */
4533                 if (err == -ENOENT)
4534                         err = 0;
4535                 goto out;
4536         }
4537
4538         err = socket_has_perm(current, sock, perm);
4539 out:
4540         return err;
4541 }
4542
4543 #ifdef CONFIG_NETFILTER
4544
4545 static unsigned int selinux_ip_forward(struct sk_buff *skb, int ifindex,
4546                                        u16 family)
4547 {
4548         int err;
4549         char *addrp;
4550         u32 peer_sid;
4551         struct avc_audit_data ad;
4552         u8 secmark_active;
4553         u8 netlbl_active;
4554         u8 peerlbl_active;
4555
4556         if (!selinux_policycap_netpeer)
4557                 return NF_ACCEPT;
4558
4559         secmark_active = selinux_secmark_enabled();
4560         netlbl_active = netlbl_enabled();
4561         peerlbl_active = netlbl_active || selinux_xfrm_enabled();
4562         if (!secmark_active && !peerlbl_active)
4563                 return NF_ACCEPT;
4564
4565         if (selinux_skb_peerlbl_sid(skb, family, &peer_sid) != 0)
4566                 return NF_DROP;
4567
4568         AVC_AUDIT_DATA_INIT(&ad, NET);
4569         ad.u.net.netif = ifindex;
4570         ad.u.net.family = family;
4571         if (selinux_parse_skb(skb, &ad, &addrp, 1, NULL) != 0)
4572                 return NF_DROP;
4573
4574         if (peerlbl_active) {
4575                 err = selinux_inet_sys_rcv_skb(ifindex, addrp, family,
4576                                                peer_sid, &ad);
4577                 if (err) {
4578                         selinux_netlbl_err(skb, err, 1);
4579                         return NF_DROP;
4580                 }
4581         }
4582
4583         if (secmark_active)
4584                 if (avc_has_perm(peer_sid, skb->secmark,
4585                                  SECCLASS_PACKET, PACKET__FORWARD_IN, &ad))
4586                         return NF_DROP;
4587
4588         if (netlbl_active)
4589                 /* we do this in the FORWARD path and not the POST_ROUTING
4590                  * path because we want to make sure we apply the necessary
4591                  * labeling before IPsec is applied so we can leverage AH
4592                  * protection */
4593                 if (selinux_netlbl_skbuff_setsid(skb, family, peer_sid) != 0)
4594                         return NF_DROP;
4595
4596         return NF_ACCEPT;
4597 }
4598
4599 static unsigned int selinux_ipv4_forward(unsigned int hooknum,
4600                                          struct sk_buff *skb,
4601                                          const struct net_device *in,
4602                                          const struct net_device *out,
4603                                          int (*okfn)(struct sk_buff *))
4604 {
4605         return selinux_ip_forward(skb, in->ifindex, PF_INET);
4606 }
4607
4608 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
4609 static unsigned int selinux_ipv6_forward(unsigned int hooknum,
4610                                          struct sk_buff *skb,
4611                                          const struct net_device *in,
4612                                          const struct net_device *out,
4613                                          int (*okfn)(struct sk_buff *))
4614 {
4615         return selinux_ip_forward(skb, in->ifindex, PF_INET6);
4616 }
4617 #endif  /* IPV6 */
4618
4619 static unsigned int selinux_ip_output(struct sk_buff *skb,
4620                                       u16 family)
4621 {
4622         u32 sid;
4623
4624         if (!netlbl_enabled())
4625                 return NF_ACCEPT;
4626
4627         /* we do this in the LOCAL_OUT path and not the POST_ROUTING path
4628          * because we want to make sure we apply the necessary labeling
4629          * before IPsec is applied so we can leverage AH protection */
4630         if (skb->sk) {
4631                 struct sk_security_struct *sksec = skb->sk->sk_security;
4632                 sid = sksec->sid;
4633         } else
4634                 sid = SECINITSID_KERNEL;
4635         if (selinux_netlbl_skbuff_setsid(skb, family, sid) != 0)
4636                 return NF_DROP;
4637
4638         return NF_ACCEPT;
4639 }
4640
4641 static unsigned int selinux_ipv4_output(unsigned int hooknum,
4642                                         struct sk_buff *skb,
4643                                         const struct net_device *in,
4644                                         const struct net_device *out,
4645                                         int (*okfn)(struct sk_buff *))
4646 {
4647         return selinux_ip_output(skb, PF_INET);
4648 }
4649
4650 static int selinux_ip_postroute_iptables_compat(struct sock *sk,
4651                                                 int ifindex,
4652                                                 struct avc_audit_data *ad,
4653                                                 u16 family, char *addrp)
4654 {
4655         int err;
4656         struct sk_security_struct *sksec = sk->sk_security;
4657         u16 sk_class;
4658         u32 netif_perm, node_perm, send_perm;
4659         u32 port_sid, node_sid, if_sid, sk_sid;
4660
4661         sk_sid = sksec->sid;
4662         sk_class = sksec->sclass;
4663
4664         switch (sk_class) {
4665         case SECCLASS_UDP_SOCKET:
4666                 netif_perm = NETIF__UDP_SEND;
4667                 node_perm = NODE__UDP_SEND;
4668                 send_perm = UDP_SOCKET__SEND_MSG;
4669                 break;
4670         case SECCLASS_TCP_SOCKET:
4671                 netif_perm = NETIF__TCP_SEND;
4672                 node_perm = NODE__TCP_SEND;
4673                 send_perm = TCP_SOCKET__SEND_MSG;
4674                 break;
4675         case SECCLASS_DCCP_SOCKET:
4676                 netif_perm = NETIF__DCCP_SEND;
4677                 node_perm = NODE__DCCP_SEND;
4678                 send_perm = DCCP_SOCKET__SEND_MSG;
4679                 break;
4680         default:
4681                 netif_perm = NETIF__RAWIP_SEND;
4682                 node_perm = NODE__RAWIP_SEND;
4683                 send_perm = 0;
4684                 break;
4685         }
4686
4687         err = sel_netif_sid(ifindex, &if_sid);
4688         if (err)
4689                 return err;
4690         err = avc_has_perm(sk_sid, if_sid, SECCLASS_NETIF, netif_perm, ad);
4691                 return err;
4692
4693         err = sel_netnode_sid(addrp, family, &node_sid);
4694         if (err)
4695                 return err;
4696         err = avc_has_perm(sk_sid, node_sid, SECCLASS_NODE, node_perm, ad);
4697         if (err)
4698                 return err;
4699
4700         if (send_perm != 0)
4701                 return 0;
4702
4703         err = sel_netport_sid(sk->sk_protocol,
4704                               ntohs(ad->u.net.dport), &port_sid);
4705         if (unlikely(err)) {
4706                 printk(KERN_WARNING
4707                        "SELinux: failure in"
4708                        " selinux_ip_postroute_iptables_compat(),"
4709                        " network port label not found\n");
4710                 return err;
4711         }
4712         return avc_has_perm(sk_sid, port_sid, sk_class, send_perm, ad);
4713 }
4714
4715 static unsigned int selinux_ip_postroute_compat(struct sk_buff *skb,
4716                                                 int ifindex,
4717                                                 u16 family)
4718 {
4719         struct sock *sk = skb->sk;
4720         struct sk_security_struct *sksec;
4721         struct avc_audit_data ad;
4722         char *addrp;
4723         u8 proto;
4724
4725         if (sk == NULL)
4726                 return NF_ACCEPT;
4727         sksec = sk->sk_security;
4728
4729         AVC_AUDIT_DATA_INIT(&ad, NET);
4730         ad.u.net.netif = ifindex;
4731         ad.u.net.family = family;
4732         if (selinux_parse_skb(skb, &ad, &addrp, 0, &proto))
4733                 return NF_DROP;
4734
4735         if (selinux_compat_net) {
4736                 if (selinux_ip_postroute_iptables_compat(skb->sk, ifindex,
4737                                                          &ad, family, addrp))
4738                         return NF_DROP;
4739         } else if (selinux_secmark_enabled()) {
4740                 if (avc_has_perm(sksec->sid, skb->secmark,
4741                                  SECCLASS_PACKET, PACKET__SEND, &ad))
4742                         return NF_DROP;
4743         }
4744
4745         if (selinux_policycap_netpeer)
4746                 if (selinux_xfrm_postroute_last(sksec->sid, skb, &ad, proto))
4747                         return NF_DROP;
4748
4749         return NF_ACCEPT;
4750 }
4751
4752 static unsigned int selinux_ip_postroute(struct sk_buff *skb, int ifindex,
4753                                          u16 family)
4754 {
4755         u32 secmark_perm;
4756         u32 peer_sid;
4757         struct sock *sk;
4758         struct avc_audit_data ad;
4759         char *addrp;
4760         u8 secmark_active;
4761         u8 peerlbl_active;
4762
4763         /* If any sort of compatibility mode is enabled then handoff processing
4764          * to the selinux_ip_postroute_compat() function to deal with the
4765          * special handling.  We do this in an attempt to keep this function
4766          * as fast and as clean as possible. */
4767         if (selinux_compat_net || !selinux_policycap_netpeer)
4768                 return selinux_ip_postroute_compat(skb, ifindex, family);
4769 #ifdef CONFIG_XFRM
4770         /* If skb->dst->xfrm is non-NULL then the packet is undergoing an IPsec
4771          * packet transformation so allow the packet to pass without any checks
4772          * since we'll have another chance to perform access control checks
4773          * when the packet is on it's final way out.
4774          * NOTE: there appear to be some IPv6 multicast cases where skb->dst
4775          *       is NULL, in this case go ahead and apply access control. */
4776         if (skb->dst != NULL && skb->dst->xfrm != NULL)
4777                 return NF_ACCEPT;
4778 #endif
4779         secmark_active = selinux_secmark_enabled();
4780         peerlbl_active = netlbl_enabled() || selinux_xfrm_enabled();
4781         if (!secmark_active && !peerlbl_active)
4782                 return NF_ACCEPT;
4783
4784         /* if the packet is being forwarded then get the peer label from the
4785          * packet itself; otherwise check to see if it is from a local
4786          * application or the kernel, if from an application get the peer label
4787          * from the sending socket, otherwise use the kernel's sid */
4788         sk = skb->sk;
4789         if (sk == NULL) {
4790                 switch (family) {
4791                 case PF_INET:
4792                         if (IPCB(skb)->flags & IPSKB_FORWARDED)
4793                                 secmark_perm = PACKET__FORWARD_OUT;
4794                         else
4795                                 secmark_perm = PACKET__SEND;
4796                         break;
4797                 case PF_INET6:
4798                         if (IP6CB(skb)->flags & IP6SKB_FORWARDED)
4799                                 secmark_perm = PACKET__FORWARD_OUT;
4800                         else
4801                                 secmark_perm = PACKET__SEND;
4802                         break;
4803                 default:
4804                         return NF_DROP;
4805                 }
4806                 if (secmark_perm == PACKET__FORWARD_OUT) {
4807                         if (selinux_skb_peerlbl_sid(skb, family, &peer_sid))
4808                                 return NF_DROP;
4809                 } else
4810                         peer_sid = SECINITSID_KERNEL;
4811         } else {
4812                 struct sk_security_struct *sksec = sk->sk_security;
4813                 peer_sid = sksec->sid;
4814                 secmark_perm = PACKET__SEND;
4815         }
4816
4817         AVC_AUDIT_DATA_INIT(&ad, NET);
4818         ad.u.net.netif = ifindex;
4819         ad.u.net.family = family;
4820         if (selinux_parse_skb(skb, &ad, &addrp, 0, NULL))
4821                 return NF_DROP;
4822
4823         if (secmark_active)
4824                 if (avc_has_perm(peer_sid, skb->secmark,
4825                                  SECCLASS_PACKET, secmark_perm, &ad))
4826                         return NF_DROP;
4827
4828         if (peerlbl_active) {
4829                 u32 if_sid;
4830                 u32 node_sid;
4831
4832                 if (sel_netif_sid(ifindex, &if_sid))
4833                         return NF_DROP;
4834                 if (avc_has_perm(peer_sid, if_sid,
4835                                  SECCLASS_NETIF, NETIF__EGRESS, &ad))
4836                         return NF_DROP;
4837
4838                 if (sel_netnode_sid(addrp, family, &node_sid))
4839                         return NF_DROP;
4840                 if (avc_has_perm(peer_sid, node_sid,
4841                                  SECCLASS_NODE, NODE__SENDTO, &ad))
4842                         return NF_DROP;
4843         }
4844
4845         return NF_ACCEPT;
4846 }
4847
4848 static unsigned int selinux_ipv4_postroute(unsigned int hooknum,
4849                                            struct sk_buff *skb,
4850                                            const struct net_device *in,
4851                                            const struct net_device *out,
4852                                            int (*okfn)(struct sk_buff *))
4853 {
4854         return selinux_ip_postroute(skb, out->ifindex, PF_INET);
4855 }
4856
4857 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
4858 static unsigned int selinux_ipv6_postroute(unsigned int hooknum,
4859                                            struct sk_buff *skb,
4860                                            const struct net_device *in,
4861                                            const struct net_device *out,
4862                                            int (*okfn)(struct sk_buff *))
4863 {
4864         return selinux_ip_postroute(skb, out->ifindex, PF_INET6);
4865 }
4866 #endif  /* IPV6 */
4867
4868 #endif  /* CONFIG_NETFILTER */
4869
4870 static int selinux_netlink_send(struct sock *sk, struct sk_buff *skb)
4871 {
4872         int err;
4873
4874         err = secondary_ops->netlink_send(sk, skb);
4875         if (err)
4876                 return err;
4877
4878         if (policydb_loaded_version >= POLICYDB_VERSION_NLCLASS)
4879                 err = selinux_nlmsg_perm(sk, skb);
4880
4881         return err;
4882 }
4883
4884 static int selinux_netlink_recv(struct sk_buff *skb, int capability)
4885 {
4886         int err;
4887         struct avc_audit_data ad;
4888
4889         err = secondary_ops->netlink_recv(skb, capability);
4890         if (err)
4891                 return err;
4892
4893         AVC_AUDIT_DATA_INIT(&ad, CAP);
4894         ad.u.cap = capability;
4895
4896         return avc_has_perm(NETLINK_CB(skb).sid, NETLINK_CB(skb).sid,
4897                             SECCLASS_CAPABILITY, CAP_TO_MASK(capability), &ad);
4898 }
4899
4900 static int ipc_alloc_security(struct task_struct *task,
4901                               struct kern_ipc_perm *perm,
4902                               u16 sclass)
4903 {
4904         struct ipc_security_struct *isec;
4905         u32 sid;
4906
4907         isec = kzalloc(sizeof(struct ipc_security_struct), GFP_KERNEL);
4908         if (!isec)
4909                 return -ENOMEM;
4910
4911         sid = task_sid(task);
4912         isec->sclass = sclass;
4913         isec->sid = sid;
4914         perm->security = isec;
4915
4916         return 0;
4917 }
4918
4919 static void ipc_free_security(struct kern_ipc_perm *perm)
4920 {
4921         struct ipc_security_struct *isec = perm->security;
4922         perm->security = NULL;
4923         kfree(isec);
4924 }
4925
4926 static int msg_msg_alloc_security(struct msg_msg *msg)
4927 {
4928         struct msg_security_struct *msec;
4929
4930         msec = kzalloc(sizeof(struct msg_security_struct), GFP_KERNEL);
4931         if (!msec)
4932                 return -ENOMEM;
4933
4934         msec->sid = SECINITSID_UNLABELED;
4935         msg->security = msec;
4936
4937         return 0;
4938 }
4939
4940 static void msg_msg_free_security(struct msg_msg *msg)
4941 {
4942         struct msg_security_struct *msec = msg->security;
4943
4944         msg->security = NULL;
4945         kfree(msec);
4946 }
4947
4948 static int ipc_has_perm(struct kern_ipc_perm *ipc_perms,
4949                         u32 perms)
4950 {
4951         struct ipc_security_struct *isec;
4952         struct avc_audit_data ad;
4953         u32 sid = current_sid();
4954
4955         isec = ipc_perms->security;
4956
4957         AVC_AUDIT_DATA_INIT(&ad, IPC);
4958         ad.u.ipc_id = ipc_perms->key;
4959
4960         return avc_has_perm(sid, isec->sid, isec->sclass, perms, &ad);
4961 }
4962
4963 static int selinux_msg_msg_alloc_security(struct msg_msg *msg)
4964 {
4965         return msg_msg_alloc_security(msg);
4966 }
4967
4968 static void selinux_msg_msg_free_security(struct msg_msg *msg)
4969 {
4970         msg_msg_free_security(msg);
4971 }
4972
4973 /* message queue security operations */
4974 static int selinux_msg_queue_alloc_security(struct msg_queue *msq)
4975 {
4976         struct ipc_security_struct *isec;
4977         struct avc_audit_data ad;
4978         u32 sid = current_sid();
4979         int rc;
4980
4981         rc = ipc_alloc_security(current, &msq->q_perm, SECCLASS_MSGQ);
4982         if (rc)
4983                 return rc;
4984
4985         isec = msq->q_perm.security;
4986
4987         AVC_AUDIT_DATA_INIT(&ad, IPC);
4988         ad.u.ipc_id = msq->q_perm.key;
4989
4990         rc = avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
4991                           MSGQ__CREATE, &ad);
4992         if (rc) {
4993                 ipc_free_security(&msq->q_perm);
4994                 return rc;
4995         }
4996         return 0;
4997 }
4998
4999 static void selinux_msg_queue_free_security(struct msg_queue *msq)
5000 {
5001         ipc_free_security(&msq->q_perm);
5002 }
5003
5004 static int selinux_msg_queue_associate(struct msg_queue *msq, int msqflg)
5005 {
5006         struct ipc_security_struct *isec;
5007         struct avc_audit_data ad;
5008         u32 sid = current_sid();
5009
5010         isec = msq->q_perm.security;
5011
5012         AVC_AUDIT_DATA_INIT(&ad, IPC);
5013         ad.u.ipc_id = msq->q_perm.key;
5014
5015         return avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
5016                             MSGQ__ASSOCIATE, &ad);
5017 }
5018
5019 static int selinux_msg_queue_msgctl(struct msg_queue *msq, int cmd)
5020 {
5021         int err;
5022         int perms;
5023
5024         switch (cmd) {
5025         case IPC_INFO:
5026         case MSG_INFO:
5027                 /* No specific object, just general system-wide information. */
5028                 return task_has_system(current, SYSTEM__IPC_INFO);
5029         case IPC_STAT:
5030         case MSG_STAT:
5031                 perms = MSGQ__GETATTR | MSGQ__ASSOCIATE;
5032                 break;
5033         case IPC_SET:
5034                 perms = MSGQ__SETATTR;
5035                 break;
5036         case IPC_RMID:
5037                 perms = MSGQ__DESTROY;
5038                 break;
5039         default:
5040                 return 0;
5041         }
5042
5043         err = ipc_has_perm(&msq->q_perm, perms);
5044         return err;
5045 }
5046
5047 static int selinux_msg_queue_msgsnd(struct msg_queue *msq, struct msg_msg *msg, int msqflg)
5048 {
5049         struct ipc_security_struct *isec;
5050         struct msg_security_struct *msec;
5051         struct avc_audit_data ad;
5052         u32 sid = current_sid();
5053         int rc;
5054
5055         isec = msq->q_perm.security;
5056         msec = msg->security;
5057
5058         /*
5059          * First time through, need to assign label to the message
5060          */
5061         if (msec->sid == SECINITSID_UNLABELED) {
5062                 /*
5063                  * Compute new sid based on current process and
5064                  * message queue this message will be stored in
5065                  */
5066                 rc = security_transition_sid(sid, isec->sid, SECCLASS_MSG,
5067                                              &msec->sid);
5068                 if (rc)
5069                         return rc;
5070         }
5071
5072         AVC_AUDIT_DATA_INIT(&ad, IPC);
5073         ad.u.ipc_id = msq->q_perm.key;
5074
5075         /* Can this process write to the queue? */
5076         rc = avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
5077                           MSGQ__WRITE, &ad);
5078         if (!rc)
5079                 /* Can this process send the message */
5080                 rc = avc_has_perm(sid, msec->sid, SECCLASS_MSG,
5081                                   MSG__SEND, &ad);
5082         if (!rc)
5083                 /* Can the message be put in the queue? */
5084                 rc = avc_has_perm(msec->sid, isec->sid, SECCLASS_MSGQ,
5085                                   MSGQ__ENQUEUE, &ad);
5086
5087         return rc;
5088 }
5089
5090 static int selinux_msg_queue_msgrcv(struct msg_queue *msq, struct msg_msg *msg,
5091                                     struct task_struct *target,
5092                                     long type, int mode)
5093 {
5094         struct ipc_security_struct *isec;
5095         struct msg_security_struct *msec;
5096         struct avc_audit_data ad;
5097         u32 sid = task_sid(target);
5098         int rc;
5099
5100         isec = msq->q_perm.security;
5101         msec = msg->security;
5102
5103         AVC_AUDIT_DATA_INIT(&ad, IPC);
5104         ad.u.ipc_id = msq->q_perm.key;
5105
5106         rc = avc_has_perm(sid, isec->sid,
5107                           SECCLASS_MSGQ, MSGQ__READ, &ad);
5108         if (!rc)
5109                 rc = avc_has_perm(sid, msec->sid,
5110                                   SECCLASS_MSG, MSG__RECEIVE, &ad);
5111         return rc;
5112 }
5113
5114 /* Shared Memory security operations */
5115 static int selinux_shm_alloc_security(struct shmid_kernel *shp)
5116 {
5117         struct ipc_security_struct *isec;
5118         struct avc_audit_data ad;
5119         u32 sid = current_sid();
5120         int rc;
5121
5122         rc = ipc_alloc_security(current, &shp->shm_perm, SECCLASS_SHM);
5123         if (rc)
5124                 return rc;
5125
5126         isec = shp->shm_perm.security;
5127
5128         AVC_AUDIT_DATA_INIT(&ad, IPC);
5129         ad.u.ipc_id = shp->shm_perm.key;
5130
5131         rc = avc_has_perm(sid, isec->sid, SECCLASS_SHM,
5132                           SHM__CREATE, &ad);
5133         if (rc) {
5134                 ipc_free_security(&shp->shm_perm);
5135                 return rc;
5136         }
5137         return 0;
5138 }
5139
5140 static void selinux_shm_free_security(struct shmid_kernel *shp)
5141 {
5142         ipc_free_security(&shp->shm_perm);
5143 }
5144
5145 static int selinux_shm_associate(struct shmid_kernel *shp, int shmflg)
5146 {
5147         struct ipc_security_struct *isec;
5148         struct avc_audit_data ad;
5149         u32 sid = current_sid();
5150
5151         isec = shp->shm_perm.security;
5152
5153         AVC_AUDIT_DATA_INIT(&ad, IPC);
5154         ad.u.ipc_id = shp->shm_perm.key;
5155
5156         return avc_has_perm(sid, isec->sid, SECCLASS_SHM,
5157                             SHM__ASSOCIATE, &ad);
5158 }
5159
5160 /* Note, at this point, shp is locked down */
5161 static int selinux_shm_shmctl(struct shmid_kernel *shp, int cmd)
5162 {
5163         int perms;
5164         int err;
5165
5166         switch (cmd) {
5167         case IPC_INFO:
5168         case SHM_INFO:
5169                 /* No specific object, just general system-wide information. */
5170                 return task_has_system(current, SYSTEM__IPC_INFO);
5171         case IPC_STAT:
5172         case SHM_STAT:
5173                 perms = SHM__GETATTR | SHM__ASSOCIATE;
5174                 break;
5175         case IPC_SET:
5176                 perms = SHM__SETATTR;
5177                 break;
5178         case SHM_LOCK:
5179         case SHM_UNLOCK:
5180                 perms = SHM__LOCK;
5181                 break;
5182         case IPC_RMID:
5183                 perms = SHM__DESTROY;
5184                 break;
5185         default:
5186                 return 0;
5187         }
5188
5189         err = ipc_has_perm(&shp->shm_perm, perms);
5190         return err;
5191 }
5192
5193 static int selinux_shm_shmat(struct shmid_kernel *shp,
5194                              char __user *shmaddr, int shmflg)
5195 {
5196         u32 perms;
5197         int rc;
5198
5199         rc = secondary_ops->shm_shmat(shp, shmaddr, shmflg);
5200         if (rc)
5201                 return rc;
5202
5203         if (shmflg & SHM_RDONLY)
5204                 perms = SHM__READ;
5205         else
5206                 perms = SHM__READ | SHM__WRITE;
5207
5208         return ipc_has_perm(&shp->shm_perm, perms);
5209 }
5210
5211 /* Semaphore security operations */
5212 static int selinux_sem_alloc_security(struct sem_array *sma)
5213 {
5214         struct ipc_security_struct *isec;
5215         struct avc_audit_data ad;
5216         u32 sid = current_sid();
5217         int rc;
5218
5219         rc = ipc_alloc_security(current, &sma->sem_perm, SECCLASS_SEM);
5220         if (rc)
5221                 return rc;
5222
5223         isec = sma->sem_perm.security;
5224
5225         AVC_AUDIT_DATA_INIT(&ad, IPC);
5226         ad.u.ipc_id = sma->sem_perm.key;
5227
5228         rc = avc_has_perm(sid, isec->sid, SECCLASS_SEM,
5229                           SEM__CREATE, &ad);
5230         if (rc) {
5231                 ipc_free_security(&sma->sem_perm);
5232                 return rc;
5233         }
5234         return 0;
5235 }
5236
5237 static void selinux_sem_free_security(struct sem_array *sma)
5238 {
5239         ipc_free_security(&sma->sem_perm);
5240 }
5241
5242 static int selinux_sem_associate(struct sem_array *sma, int semflg)
5243 {
5244         struct ipc_security_struct *isec;
5245         struct avc_audit_data ad;
5246         u32 sid = current_sid();
5247
5248         isec = sma->sem_perm.security;
5249
5250         AVC_AUDIT_DATA_INIT(&ad, IPC);
5251         ad.u.ipc_id = sma->sem_perm.key;
5252
5253         return avc_has_perm(sid, isec->sid, SECCLASS_SEM,
5254                             SEM__ASSOCIATE, &ad);
5255 }
5256
5257 /* Note, at this point, sma is locked down */
5258 static int selinux_sem_semctl(struct sem_array *sma, int cmd)
5259 {
5260         int err;
5261         u32 perms;
5262
5263         switch (cmd) {
5264         case IPC_INFO:
5265         case SEM_INFO:
5266                 /* No specific object, just general system-wide information. */
5267                 return task_has_system(current, SYSTEM__IPC_INFO);
5268         case GETPID:
5269         case GETNCNT:
5270         case GETZCNT:
5271                 perms = SEM__GETATTR;
5272                 break;
5273         case GETVAL:
5274         case GETALL:
5275                 perms = SEM__READ;
5276                 break;
5277         case SETVAL:
5278         case SETALL:
5279                 perms = SEM__WRITE;
5280                 break;
5281         case IPC_RMID:
5282                 perms = SEM__DESTROY;
5283                 break;
5284         case IPC_SET:
5285                 perms = SEM__SETATTR;
5286                 break;
5287         case IPC_STAT:
5288         case SEM_STAT:
5289                 perms = SEM__GETATTR | SEM__ASSOCIATE;
5290                 break;
5291         default:
5292                 return 0;
5293         }
5294
5295         err = ipc_has_perm(&sma->sem_perm, perms);
5296         return err;
5297 }
5298
5299 static int selinux_sem_semop(struct sem_array *sma,
5300                              struct sembuf *sops, unsigned nsops, int alter)
5301 {
5302         u32 perms;
5303
5304         if (alter)
5305                 perms = SEM__READ | SEM__WRITE;
5306         else
5307                 perms = SEM__READ;
5308
5309         return ipc_has_perm(&sma->sem_perm, perms);
5310 }
5311
5312 static int selinux_ipc_permission(struct kern_ipc_perm *ipcp, short flag)
5313 {
5314         u32 av = 0;
5315
5316         av = 0;
5317         if (flag & S_IRUGO)
5318                 av |= IPC__UNIX_READ;
5319         if (flag & S_IWUGO)
5320                 av |= IPC__UNIX_WRITE;
5321
5322         if (av == 0)
5323                 return 0;
5324
5325         return ipc_has_perm(ipcp, av);
5326 }
5327
5328 static void selinux_ipc_getsecid(struct kern_ipc_perm *ipcp, u32 *secid)
5329 {
5330         struct ipc_security_struct *isec = ipcp->security;
5331         *secid = isec->sid;
5332 }
5333
5334 static void selinux_d_instantiate(struct dentry *dentry, struct inode *inode)
5335 {
5336         if (inode)
5337                 inode_doinit_with_dentry(inode, dentry);
5338 }
5339
5340 static int selinux_getprocattr(struct task_struct *p,
5341                                char *name, char **value)
5342 {
5343         const struct task_security_struct *__tsec;
5344         u32 sid;
5345         int error;
5346         unsigned len;
5347
5348         if (current != p) {
5349                 error = current_has_perm(p, PROCESS__GETATTR);
5350                 if (error)
5351                         return error;
5352         }
5353
5354         rcu_read_lock();
5355         __tsec = __task_cred(p)->security;
5356
5357         if (!strcmp(name, "current"))
5358                 sid = __tsec->sid;
5359         else if (!strcmp(name, "prev"))
5360                 sid = __tsec->osid;
5361         else if (!strcmp(name, "exec"))
5362                 sid = __tsec->exec_sid;
5363         else if (!strcmp(name, "fscreate"))
5364                 sid = __tsec->create_sid;
5365         else if (!strcmp(name, "keycreate"))
5366                 sid = __tsec->keycreate_sid;
5367         else if (!strcmp(name, "sockcreate"))
5368                 sid = __tsec->sockcreate_sid;
5369         else
5370                 goto invalid;
5371         rcu_read_unlock();
5372
5373         if (!sid)
5374                 return 0;
5375
5376         error = security_sid_to_context(sid, value, &len);
5377         if (error)
5378                 return error;
5379         return len;
5380
5381 invalid:
5382         rcu_read_unlock();
5383         return -EINVAL;
5384 }
5385
5386 static int selinux_setprocattr(struct task_struct *p,
5387                                char *name, void *value, size_t size)
5388 {
5389         struct task_security_struct *tsec;
5390         struct task_struct *tracer;
5391         struct cred *new;
5392         u32 sid = 0, ptsid;
5393         int error;
5394         char *str = value;
5395
5396         if (current != p) {
5397                 /* SELinux only allows a process to change its own
5398                    security attributes. */
5399                 return -EACCES;
5400         }
5401
5402         /*
5403          * Basic control over ability to set these attributes at all.
5404          * current == p, but we'll pass them separately in case the
5405          * above restriction is ever removed.
5406          */
5407         if (!strcmp(name, "exec"))
5408                 error = current_has_perm(p, PROCESS__SETEXEC);
5409         else if (!strcmp(name, "fscreate"))
5410                 error = current_has_perm(p, PROCESS__SETFSCREATE);
5411         else if (!strcmp(name, "keycreate"))
5412                 error = current_has_perm(p, PROCESS__SETKEYCREATE);
5413         else if (!strcmp(name, "sockcreate"))
5414                 error = current_has_perm(p, PROCESS__SETSOCKCREATE);
5415         else if (!strcmp(name, "current"))
5416                 error = current_has_perm(p, PROCESS__SETCURRENT);
5417         else
5418                 error = -EINVAL;
5419         if (error)
5420                 return error;
5421
5422         /* Obtain a SID for the context, if one was specified. */
5423         if (size && str[1] && str[1] != '\n') {
5424                 if (str[size-1] == '\n') {
5425                         str[size-1] = 0;
5426                         size--;
5427                 }
5428                 error = security_context_to_sid(value, size, &sid);
5429                 if (error == -EINVAL && !strcmp(name, "fscreate")) {
5430                         if (!capable(CAP_MAC_ADMIN))
5431                                 return error;
5432                         error = security_context_to_sid_force(value, size,
5433                                                               &sid);
5434                 }
5435                 if (error)
5436                         return error;
5437         }
5438
5439         new = prepare_creds();
5440         if (!new)
5441                 return -ENOMEM;
5442
5443         /* Permission checking based on the specified context is
5444            performed during the actual operation (execve,
5445            open/mkdir/...), when we know the full context of the
5446            operation.  See selinux_bprm_set_creds for the execve
5447            checks and may_create for the file creation checks. The
5448            operation will then fail if the context is not permitted. */
5449         tsec = new->security;
5450         if (!strcmp(name, "exec")) {
5451                 tsec->exec_sid = sid;
5452         } else if (!strcmp(name, "fscreate")) {
5453                 tsec->create_sid = sid;
5454         } else if (!strcmp(name, "keycreate")) {
5455                 error = may_create_key(sid, p);
5456                 if (error)
5457                         goto abort_change;
5458                 tsec->keycreate_sid = sid;
5459         } else if (!strcmp(name, "sockcreate")) {
5460                 tsec->sockcreate_sid = sid;
5461         } else if (!strcmp(name, "current")) {
5462                 error = -EINVAL;
5463                 if (sid == 0)
5464                         goto abort_change;
5465
5466                 /* Only allow single threaded processes to change context */
5467                 error = -EPERM;
5468                 if (!is_single_threaded(p)) {
5469                         error = security_bounded_transition(tsec->sid, sid);
5470                         if (error)
5471                                 goto abort_change;
5472                 }
5473
5474                 /* Check permissions for the transition. */
5475                 error = avc_has_perm(tsec->sid, sid, SECCLASS_PROCESS,
5476                                      PROCESS__DYNTRANSITION, NULL);
5477                 if (error)
5478                         goto abort_change;
5479
5480                 /* Check for ptracing, and update the task SID if ok.
5481                    Otherwise, leave SID unchanged and fail. */
5482                 ptsid = 0;
5483                 task_lock(p);
5484                 tracer = tracehook_tracer_task(p);
5485                 if (tracer)
5486                         ptsid = task_sid(tracer);
5487                 task_unlock(p);
5488
5489                 if (tracer) {
5490                         error = avc_has_perm(ptsid, sid, SECCLASS_PROCESS,
5491                                              PROCESS__PTRACE, NULL);
5492                         if (error)
5493                                 goto abort_change;
5494                 }
5495
5496                 tsec->sid = sid;
5497         } else {
5498                 error = -EINVAL;
5499                 goto abort_change;
5500         }
5501
5502         commit_creds(new);
5503         return size;
5504
5505 abort_change:
5506         abort_creds(new);
5507         return error;
5508 }
5509
5510 static int selinux_secid_to_secctx(u32 secid, char **secdata, u32 *seclen)
5511 {
5512         return security_sid_to_context(secid, secdata, seclen);
5513 }
5514
5515 static int selinux_secctx_to_secid(const char *secdata, u32 seclen, u32 *secid)
5516 {
5517         return security_context_to_sid(secdata, seclen, secid);
5518 }
5519
5520 static void selinux_release_secctx(char *secdata, u32 seclen)
5521 {
5522         kfree(secdata);
5523 }
5524
5525 #ifdef CONFIG_KEYS
5526
5527 static int selinux_key_alloc(struct key *k, const struct cred *cred,
5528                              unsigned long flags)
5529 {
5530         const struct task_security_struct *tsec;
5531         struct key_security_struct *ksec;
5532
5533         ksec = kzalloc(sizeof(struct key_security_struct), GFP_KERNEL);
5534         if (!ksec)
5535                 return -ENOMEM;
5536
5537         tsec = cred->security;
5538         if (tsec->keycreate_sid)
5539                 ksec->sid = tsec->keycreate_sid;
5540         else
5541                 ksec->sid = tsec->sid;
5542
5543         k->security = ksec;
5544         return 0;
5545 }
5546
5547 static void selinux_key_free(struct key *k)
5548 {
5549         struct key_security_struct *ksec = k->security;
5550
5551         k->security = NULL;
5552         kfree(ksec);
5553 }
5554
5555 static int selinux_key_permission(key_ref_t key_ref,
5556                                   const struct cred *cred,
5557                                   key_perm_t perm)
5558 {
5559         struct key *key;
5560         struct key_security_struct *ksec;
5561         u32 sid;
5562
5563         /* if no specific permissions are requested, we skip the
5564            permission check. No serious, additional covert channels
5565            appear to be created. */
5566         if (perm == 0)
5567                 return 0;
5568
5569         sid = cred_sid(cred);
5570
5571         key = key_ref_to_ptr(key_ref);
5572         ksec = key->security;
5573
5574         return avc_has_perm(sid, ksec->sid, SECCLASS_KEY, perm, NULL);
5575 }
5576
5577 static int selinux_key_getsecurity(struct key *key, char **_buffer)
5578 {
5579         struct key_security_struct *ksec = key->security;
5580         char *context = NULL;
5581         unsigned len;
5582         int rc;
5583
5584         rc = security_sid_to_context(ksec->sid, &context, &len);
5585         if (!rc)
5586                 rc = len;
5587         *_buffer = context;
5588         return rc;
5589 }
5590
5591 #endif
5592
5593 static struct security_operations selinux_ops = {
5594         .name =                         "selinux",
5595
5596         .ptrace_may_access =            selinux_ptrace_may_access,
5597         .ptrace_traceme =               selinux_ptrace_traceme,
5598         .capget =                       selinux_capget,
5599         .capset =                       selinux_capset,
5600         .sysctl =                       selinux_sysctl,
5601         .capable =                      selinux_capable,
5602         .quotactl =                     selinux_quotactl,
5603         .quota_on =                     selinux_quota_on,
5604         .syslog =                       selinux_syslog,
5605         .vm_enough_memory =             selinux_vm_enough_memory,
5606
5607         .netlink_send =                 selinux_netlink_send,
5608         .netlink_recv =                 selinux_netlink_recv,
5609
5610         .bprm_set_creds =               selinux_bprm_set_creds,
5611         .bprm_check_security =          selinux_bprm_check_security,
5612         .bprm_committing_creds =        selinux_bprm_committing_creds,
5613         .bprm_committed_creds =         selinux_bprm_committed_creds,
5614         .bprm_secureexec =              selinux_bprm_secureexec,
5615
5616         .sb_alloc_security =            selinux_sb_alloc_security,
5617         .sb_free_security =             selinux_sb_free_security,
5618         .sb_copy_data =                 selinux_sb_copy_data,
5619         .sb_kern_mount =                selinux_sb_kern_mount,
5620         .sb_show_options =              selinux_sb_show_options,
5621         .sb_statfs =                    selinux_sb_statfs,
5622         .sb_mount =                     selinux_mount,
5623         .sb_umount =                    selinux_umount,
5624         .sb_set_mnt_opts =              selinux_set_mnt_opts,
5625         .sb_clone_mnt_opts =            selinux_sb_clone_mnt_opts,
5626         .sb_parse_opts_str =            selinux_parse_opts_str,
5627
5628
5629         .inode_alloc_security =         selinux_inode_alloc_security,
5630         .inode_free_security =          selinux_inode_free_security,
5631         .inode_init_security =          selinux_inode_init_security,
5632         .inode_create =                 selinux_inode_create,
5633         .inode_link =                   selinux_inode_link,
5634         .inode_unlink =                 selinux_inode_unlink,
5635         .inode_symlink =                selinux_inode_symlink,
5636         .inode_mkdir =                  selinux_inode_mkdir,
5637         .inode_rmdir =                  selinux_inode_rmdir,
5638         .inode_mknod =                  selinux_inode_mknod,
5639         .inode_rename =                 selinux_inode_rename,
5640         .inode_readlink =               selinux_inode_readlink,
5641         .inode_follow_link =            selinux_inode_follow_link,
5642         .inode_permission =             selinux_inode_permission,
5643         .inode_setattr =                selinux_inode_setattr,
5644         .inode_getattr =                selinux_inode_getattr,
5645         .inode_setxattr =               selinux_inode_setxattr,
5646         .inode_post_setxattr =          selinux_inode_post_setxattr,
5647         .inode_getxattr =               selinux_inode_getxattr,
5648         .inode_listxattr =              selinux_inode_listxattr,
5649         .inode_removexattr =            selinux_inode_removexattr,
5650         .inode_getsecurity =            selinux_inode_getsecurity,
5651         .inode_setsecurity =            selinux_inode_setsecurity,
5652         .inode_listsecurity =           selinux_inode_listsecurity,
5653         .inode_need_killpriv =          selinux_inode_need_killpriv,
5654         .inode_killpriv =               selinux_inode_killpriv,
5655         .inode_getsecid =               selinux_inode_getsecid,
5656
5657         .file_permission =              selinux_file_permission,
5658         .file_alloc_security =          selinux_file_alloc_security,
5659         .file_free_security =           selinux_file_free_security,
5660         .file_ioctl =                   selinux_file_ioctl,
5661         .file_mmap =                    selinux_file_mmap,
5662         .file_mprotect =                selinux_file_mprotect,
5663         .file_lock =                    selinux_file_lock,
5664         .file_fcntl =                   selinux_file_fcntl,
5665         .file_set_fowner =              selinux_file_set_fowner,
5666         .file_send_sigiotask =          selinux_file_send_sigiotask,
5667         .file_receive =                 selinux_file_receive,
5668
5669         .dentry_open =                  selinux_dentry_open,
5670
5671         .task_create =                  selinux_task_create,
5672         .cred_free =                    selinux_cred_free,
5673         .cred_prepare =                 selinux_cred_prepare,
5674         .cred_commit =                  selinux_cred_commit,
5675         .kernel_act_as =                selinux_kernel_act_as,
5676         .kernel_create_files_as =       selinux_kernel_create_files_as,
5677         .task_setuid =                  selinux_task_setuid,
5678         .task_fix_setuid =              selinux_task_fix_setuid,
5679         .task_setgid =                  selinux_task_setgid,
5680         .task_setpgid =                 selinux_task_setpgid,
5681         .task_getpgid =                 selinux_task_getpgid,
5682         .task_getsid =                  selinux_task_getsid,
5683         .task_getsecid =                selinux_task_getsecid,
5684         .task_setgroups =               selinux_task_setgroups,
5685         .task_setnice =                 selinux_task_setnice,
5686         .task_setioprio =               selinux_task_setioprio,
5687         .task_getioprio =               selinux_task_getioprio,
5688         .task_setrlimit =               selinux_task_setrlimit,
5689         .task_setscheduler =            selinux_task_setscheduler,
5690         .task_getscheduler =            selinux_task_getscheduler,
5691         .task_movememory =              selinux_task_movememory,
5692         .task_kill =                    selinux_task_kill,
5693         .task_wait =                    selinux_task_wait,
5694         .task_prctl =                   selinux_task_prctl,
5695         .task_to_inode =                selinux_task_to_inode,
5696
5697         .ipc_permission =               selinux_ipc_permission,
5698         .ipc_getsecid =                 selinux_ipc_getsecid,
5699
5700         .msg_msg_alloc_security =       selinux_msg_msg_alloc_security,
5701         .msg_msg_free_security =        selinux_msg_msg_free_security,
5702
5703         .msg_queue_alloc_security =     selinux_msg_queue_alloc_security,
5704         .msg_queue_free_security =      selinux_msg_queue_free_security,
5705         .msg_queue_associate =          selinux_msg_queue_associate,
5706         .msg_queue_msgctl =             selinux_msg_queue_msgctl,
5707         .msg_queue_msgsnd =             selinux_msg_queue_msgsnd,
5708         .msg_queue_msgrcv =             selinux_msg_queue_msgrcv,
5709
5710         .shm_alloc_security =           selinux_shm_alloc_security,
5711         .shm_free_security =            selinux_shm_free_security,
5712         .shm_associate =                selinux_shm_associate,
5713         .shm_shmctl =                   selinux_shm_shmctl,
5714         .shm_shmat =                    selinux_shm_shmat,
5715
5716         .sem_alloc_security =           selinux_sem_alloc_security,
5717         .sem_free_security =            selinux_sem_free_security,
5718         .sem_associate =                selinux_sem_associate,
5719         .sem_semctl =                   selinux_sem_semctl,
5720         .sem_semop =                    selinux_sem_semop,
5721
5722         .d_instantiate =                selinux_d_instantiate,
5723
5724         .getprocattr =                  selinux_getprocattr,
5725         .setprocattr =                  selinux_setprocattr,
5726
5727         .secid_to_secctx =              selinux_secid_to_secctx,
5728         .secctx_to_secid =              selinux_secctx_to_secid,
5729         .release_secctx =               selinux_release_secctx,
5730
5731         .unix_stream_connect =          selinux_socket_unix_stream_connect,
5732         .unix_may_send =                selinux_socket_unix_may_send,
5733
5734         .socket_create =                selinux_socket_create,
5735         .socket_post_create =           selinux_socket_post_create,
5736         .socket_bind =                  selinux_socket_bind,
5737         .socket_connect =               selinux_socket_connect,
5738         .socket_listen =                selinux_socket_listen,
5739         .socket_accept =                selinux_socket_accept,
5740         .socket_sendmsg =               selinux_socket_sendmsg,
5741         .socket_recvmsg =               selinux_socket_recvmsg,
5742         .socket_getsockname =           selinux_socket_getsockname,
5743         .socket_getpeername =           selinux_socket_getpeername,
5744         .socket_getsockopt =            selinux_socket_getsockopt,
5745         .socket_setsockopt =            selinux_socket_setsockopt,
5746         .socket_shutdown =              selinux_socket_shutdown,
5747         .socket_sock_rcv_skb =          selinux_socket_sock_rcv_skb,
5748         .socket_getpeersec_stream =     selinux_socket_getpeersec_stream,
5749         .socket_getpeersec_dgram =      selinux_socket_getpeersec_dgram,
5750         .sk_alloc_security =            selinux_sk_alloc_security,
5751         .sk_free_security =             selinux_sk_free_security,
5752         .sk_clone_security =            selinux_sk_clone_security,
5753         .sk_getsecid =                  selinux_sk_getsecid,
5754         .sock_graft =                   selinux_sock_graft,
5755         .inet_conn_request =            selinux_inet_conn_request,
5756         .inet_csk_clone =               selinux_inet_csk_clone,
5757         .inet_conn_established =        selinux_inet_conn_established,
5758         .req_classify_flow =            selinux_req_classify_flow,
5759
5760 #ifdef CONFIG_SECURITY_NETWORK_XFRM
5761         .xfrm_policy_alloc_security =   selinux_xfrm_policy_alloc,
5762         .xfrm_policy_clone_security =   selinux_xfrm_policy_clone,
5763         .xfrm_policy_free_security =    selinux_xfrm_policy_free,
5764         .xfrm_policy_delete_security =  selinux_xfrm_policy_delete,
5765         .xfrm_state_alloc_security =    selinux_xfrm_state_alloc,
5766         .xfrm_state_free_security =     selinux_xfrm_state_free,
5767         .xfrm_state_delete_security =   selinux_xfrm_state_delete,
5768         .xfrm_policy_lookup =           selinux_xfrm_policy_lookup,
5769         .xfrm_state_pol_flow_match =    selinux_xfrm_state_pol_flow_match,
5770         .xfrm_decode_session =          selinux_xfrm_decode_session,
5771 #endif
5772
5773 #ifdef CONFIG_KEYS
5774         .key_alloc =                    selinux_key_alloc,
5775         .key_free =                     selinux_key_free,
5776         .key_permission =               selinux_key_permission,
5777         .key_getsecurity =              selinux_key_getsecurity,
5778 #endif
5779
5780 #ifdef CONFIG_AUDIT
5781         .audit_rule_init =              selinux_audit_rule_init,
5782         .audit_rule_known =             selinux_audit_rule_known,
5783         .audit_rule_match =             selinux_audit_rule_match,
5784         .audit_rule_free =              selinux_audit_rule_free,
5785 #endif
5786 };
5787
5788 static __init int selinux_init(void)
5789 {
5790         if (!security_module_enable(&selinux_ops)) {
5791                 selinux_enabled = 0;
5792                 return 0;
5793         }
5794
5795         if (!selinux_enabled) {
5796                 printk(KERN_INFO "SELinux:  Disabled at boot.\n");
5797                 return 0;
5798         }
5799
5800         printk(KERN_INFO "SELinux:  Initializing.\n");
5801
5802         /* Set the security state for the initial task. */
5803         cred_init_security();
5804
5805         sel_inode_cache = kmem_cache_create("selinux_inode_security",
5806                                             sizeof(struct inode_security_struct),
5807                                             0, SLAB_PANIC, NULL);
5808         avc_init();
5809
5810         secondary_ops = security_ops;
5811         if (!secondary_ops)
5812                 panic("SELinux: No initial security operations\n");
5813         if (register_security(&selinux_ops))
5814                 panic("SELinux: Unable to register with kernel.\n");
5815
5816         if (selinux_enforcing)
5817                 printk(KERN_DEBUG "SELinux:  Starting in enforcing mode\n");
5818         else
5819                 printk(KERN_DEBUG "SELinux:  Starting in permissive mode\n");
5820
5821         return 0;
5822 }
5823
5824 void selinux_complete_init(void)
5825 {
5826         printk(KERN_DEBUG "SELinux:  Completing initialization.\n");
5827
5828         /* Set up any superblocks initialized prior to the policy load. */
5829         printk(KERN_DEBUG "SELinux:  Setting up existing superblocks.\n");
5830         spin_lock(&sb_lock);
5831         spin_lock(&sb_security_lock);
5832 next_sb:
5833         if (!list_empty(&superblock_security_head)) {
5834                 struct superblock_security_struct *sbsec =
5835                                 list_entry(superblock_security_head.next,
5836                                            struct superblock_security_struct,
5837                                            list);
5838                 struct super_block *sb = sbsec->sb;
5839                 sb->s_count++;
5840                 spin_unlock(&sb_security_lock);
5841                 spin_unlock(&sb_lock);
5842                 down_read(&sb->s_umount);
5843                 if (sb->s_root)
5844                         superblock_doinit(sb, NULL);
5845                 drop_super(sb);
5846                 spin_lock(&sb_lock);
5847                 spin_lock(&sb_security_lock);
5848                 list_del_init(&sbsec->list);
5849                 goto next_sb;
5850         }
5851         spin_unlock(&sb_security_lock);
5852         spin_unlock(&sb_lock);
5853 }
5854
5855 /* SELinux requires early initialization in order to label
5856    all processes and objects when they are created. */
5857 security_initcall(selinux_init);
5858
5859 #if defined(CONFIG_NETFILTER)
5860
5861 static struct nf_hook_ops selinux_ipv4_ops[] = {
5862         {
5863                 .hook =         selinux_ipv4_postroute,
5864                 .owner =        THIS_MODULE,
5865                 .pf =           PF_INET,
5866                 .hooknum =      NF_INET_POST_ROUTING,
5867                 .priority =     NF_IP_PRI_SELINUX_LAST,
5868         },
5869         {
5870                 .hook =         selinux_ipv4_forward,
5871                 .owner =        THIS_MODULE,
5872                 .pf =           PF_INET,
5873                 .hooknum =      NF_INET_FORWARD,
5874                 .priority =     NF_IP_PRI_SELINUX_FIRST,
5875         },
5876         {
5877                 .hook =         selinux_ipv4_output,
5878                 .owner =        THIS_MODULE,
5879                 .pf =           PF_INET,
5880                 .hooknum =      NF_INET_LOCAL_OUT,
5881                 .priority =     NF_IP_PRI_SELINUX_FIRST,
5882         }
5883 };
5884
5885 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
5886
5887 static struct nf_hook_ops selinux_ipv6_ops[] = {
5888         {
5889                 .hook =         selinux_ipv6_postroute,
5890                 .owner =        THIS_MODULE,
5891                 .pf =           PF_INET6,
5892                 .hooknum =      NF_INET_POST_ROUTING,
5893                 .priority =     NF_IP6_PRI_SELINUX_LAST,
5894         },
5895         {
5896                 .hook =         selinux_ipv6_forward,
5897                 .owner =        THIS_MODULE,
5898                 .pf =           PF_INET6,
5899                 .hooknum =      NF_INET_FORWARD,
5900                 .priority =     NF_IP6_PRI_SELINUX_FIRST,
5901         }
5902 };
5903
5904 #endif  /* IPV6 */
5905
5906 static int __init selinux_nf_ip_init(void)
5907 {
5908         int err = 0;
5909
5910         if (!selinux_enabled)
5911                 goto out;
5912
5913         printk(KERN_DEBUG "SELinux:  Registering netfilter hooks\n");
5914
5915         err = nf_register_hooks(selinux_ipv4_ops, ARRAY_SIZE(selinux_ipv4_ops));
5916         if (err)
5917                 panic("SELinux: nf_register_hooks for IPv4: error %d\n", err);
5918
5919 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
5920         err = nf_register_hooks(selinux_ipv6_ops, ARRAY_SIZE(selinux_ipv6_ops));
5921         if (err)
5922                 panic("SELinux: nf_register_hooks for IPv6: error %d\n", err);
5923 #endif  /* IPV6 */
5924
5925 out:
5926         return err;
5927 }
5928
5929 __initcall(selinux_nf_ip_init);
5930
5931 #ifdef CONFIG_SECURITY_SELINUX_DISABLE
5932 static void selinux_nf_ip_exit(void)
5933 {
5934         printk(KERN_DEBUG "SELinux:  Unregistering netfilter hooks\n");
5935
5936         nf_unregister_hooks(selinux_ipv4_ops, ARRAY_SIZE(selinux_ipv4_ops));
5937 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
5938         nf_unregister_hooks(selinux_ipv6_ops, ARRAY_SIZE(selinux_ipv6_ops));
5939 #endif  /* IPV6 */
5940 }
5941 #endif
5942
5943 #else /* CONFIG_NETFILTER */
5944
5945 #ifdef CONFIG_SECURITY_SELINUX_DISABLE
5946 #define selinux_nf_ip_exit()
5947 #endif
5948
5949 #endif /* CONFIG_NETFILTER */
5950
5951 #ifdef CONFIG_SECURITY_SELINUX_DISABLE
5952 static int selinux_disabled;
5953
5954 int selinux_disable(void)
5955 {
5956         extern void exit_sel_fs(void);
5957
5958         if (ss_initialized) {
5959                 /* Not permitted after initial policy load. */
5960                 return -EINVAL;
5961         }
5962
5963         if (selinux_disabled) {
5964                 /* Only do this once. */
5965                 return -EINVAL;
5966         }
5967
5968         printk(KERN_INFO "SELinux:  Disabled at runtime.\n");
5969
5970         selinux_disabled = 1;
5971         selinux_enabled = 0;
5972
5973         /* Reset security_ops to the secondary module, dummy or capability. */
5974         security_ops = secondary_ops;
5975
5976         /* Unregister netfilter hooks. */
5977         selinux_nf_ip_exit();
5978
5979         /* Unregister selinuxfs. */
5980         exit_sel_fs();
5981
5982         return 0;
5983 }
5984 #endif