security/selinux/hooks.c

   1 /*
   2  *  NSA Security-Enhanced Linux (SELinux) security module
   3  *
   4  *  This file contains the SELinux hook function implementations.
   5  *
   6  *  Authors:  Stephen Smalley, <sds@epoch.ncsc.mil>
   7  *            Chris Vance, <cvance@nai.com>
   8  *            Wayne Salamon, <wsalamon@nai.com>
   9  *            James Morris <jmorris@redhat.com>
  10  *
  11  *  Copyright (C) 2001,2002 Networks Associates Technology, Inc.
  12  *  Copyright (C) 2003 Red Hat, Inc., James Morris <jmorris@redhat.com>
  13  *  Copyright (C) 2004-2005 Trusted Computer Solutions, Inc.
  14  *                          <dgoeddel@trustedcs.com>
  15  *
  16  *      This program is free software; you can redistribute it and/or modify
  17  *      it under the terms of the GNU General Public License version 2,
  18  *      as published by the Free Software Foundation.
  19  */
  20
  21 #include <linux/module.h>
  22 #include <linux/init.h>
  23 #include <linux/kernel.h>
  24 #include <linux/ptrace.h>
  25 #include <linux/errno.h>
  26 #include <linux/sched.h>
  27 #include <linux/security.h>
  28 #include <linux/xattr.h>
  29 #include <linux/capability.h>
  30 #include <linux/unistd.h>
  31 #include <linux/mm.h>
  32 #include <linux/mman.h>
  33 #include <linux/slab.h>
  34 #include <linux/pagemap.h>
  35 #include <linux/swap.h>
  36 #include <linux/smp_lock.h>
  37 #include <linux/spinlock.h>
  38 #include <linux/syscalls.h>
  39 #include <linux/file.h>
  40 #include <linux/namei.h>
  41 #include <linux/mount.h>
  42 #include <linux/ext2_fs.h>
  43 #include <linux/proc_fs.h>
  44 #include <linux/kd.h>
  45 #include <linux/netfilter_ipv4.h>
  46 #include <linux/netfilter_ipv6.h>
  47 #include <linux/tty.h>
  48 #include <net/icmp.h>
  49 #include <net/ip.h>             /* for sysctl_local_port_range[] */
  50 #include <net/tcp.h>            /* struct or_callable used in sock_rcv_skb */
  51 #include <asm/uaccess.h>
  52 #include <asm/semaphore.h>
  53 #include <asm/ioctls.h>
  54 #include <linux/bitops.h>
  55 #include <linux/interrupt.h>
  56 #include <linux/netdevice.h>    /* for network interface checks */
  57 #include <linux/netlink.h>
  58 #include <linux/tcp.h>
  59 #include <linux/udp.h>
  60 #include <linux/quota.h>
  61 #include <linux/un.h>           /* for Unix socket types */
  62 #include <net/af_unix.h>        /* for Unix socket types */
  63 #include <linux/parser.h>
  64 #include <linux/nfs_mount.h>
  65 #include <net/ipv6.h>
  66 #include <linux/hugetlb.h>
  67 #include <linux/personality.h>
  68 #include <linux/sysctl.h>
  69 #include <linux/audit.h>
  70 #include <linux/string.h>
  71 #include <linux/selinux.h>
  72
  73 #include "avc.h"
  74 #include "objsec.h"
  75 #include "netif.h"
  76 #include "xfrm.h"
  77
  78 #define XATTR_SELINUX_SUFFIX "selinux"
  79 #define XATTR_NAME_SELINUX XATTR_SECURITY_PREFIX XATTR_SELINUX_SUFFIX
  80
  81 extern unsigned int policydb_loaded_version;
  82 extern int selinux_nlmsg_lookup(u16 sclass, u16 nlmsg_type, u32 *perm);
  83 extern int selinux_compat_net;
  84
  85 #ifdef CONFIG_SECURITY_SELINUX_DEVELOP
  86 int selinux_enforcing = 0;
  87
  88 static int __init enforcing_setup(char *str)
  89 {
  90         selinux_enforcing = simple_strtol(str,NULL,0);
  91         return 1;
  92 }
  93 __setup("enforcing=", enforcing_setup);
  94 #endif
  95
  96 #ifdef CONFIG_SECURITY_SELINUX_BOOTPARAM
  97 int selinux_enabled = CONFIG_SECURITY_SELINUX_BOOTPARAM_VALUE;
  98
  99 static int __init selinux_enabled_setup(char *str)
 100 {
 101         selinux_enabled = simple_strtol(str, NULL, 0);
 102         return 1;
 103 }
 104 __setup("selinux=", selinux_enabled_setup);
 105 #else
 106 int selinux_enabled = 1;
 107 #endif
 108
 109 /* Original (dummy) security module. */
 110 static struct security_operations *original_ops = NULL;
 111
 112 /* Minimal support for a secondary security module,
 113    just to allow the use of the dummy or capability modules.
 114    The owlsm module can alternatively be used as a secondary
 115    module as long as CONFIG_OWLSM_FD is not enabled. */
 116 static struct security_operations *secondary_ops = NULL;
 117
 118 /* Lists of inode and superblock security structures initialized
 119    before the policy was loaded. */
 120 static LIST_HEAD(superblock_security_head);
 121 static DEFINE_SPINLOCK(sb_security_lock);
 122
 123 static kmem_cache_t *sel_inode_cache;
 124
 125 /* Return security context for a given sid or just the context
 126    length if the buffer is null or length is 0 */
 127 static int selinux_getsecurity(u32 sid, void *buffer, size_t size)
 128 {
 129         char *context;
 130         unsigned len;
 131         int rc;
 132
 133         rc = security_sid_to_context(sid, &context, &len);
 134         if (rc)
 135                 return rc;
 136
 137         if (!buffer || !size)
 138                 goto getsecurity_exit;
 139
 140         if (size < len) {
 141                 len = -ERANGE;
 142                 goto getsecurity_exit;
 143         }
 144         memcpy(buffer, context, len);
 145
 146 getsecurity_exit:
 147         kfree(context);
 148         return len;
 149 }
 150
 151 /* Allocate and free functions for each kind of security blob. */
 152
 153 static int task_alloc_security(struct task_struct *task)
 154 {
 155         struct task_security_struct *tsec;
 156
 157         tsec = kzalloc(sizeof(struct task_security_struct), GFP_KERNEL);
 158         if (!tsec)
 159                 return -ENOMEM;
 160
 161         tsec->task = task;
 162         tsec->osid = tsec->sid = tsec->ptrace_sid = SECINITSID_UNLABELED;
 163         task->security = tsec;
 164
 165         return 0;
 166 }
 167
 168 static void task_free_security(struct task_struct *task)
 169 {
 170         struct task_security_struct *tsec = task->security;
 171         task->security = NULL;
 172         kfree(tsec);
 173 }
 174
 175 static int inode_alloc_security(struct inode *inode)
 176 {
 177         struct task_security_struct *tsec = current->security;
 178         struct inode_security_struct *isec;
 179
 180         isec = kmem_cache_alloc(sel_inode_cache, SLAB_KERNEL);
 181         if (!isec)
 182                 return -ENOMEM;
 183
 184         memset(isec, 0, sizeof(*isec));
 185         init_MUTEX(&isec->sem);
 186         INIT_LIST_HEAD(&isec->list);
 187         isec->inode = inode;
 188         isec->sid = SECINITSID_UNLABELED;
 189         isec->sclass = SECCLASS_FILE;
 190         isec->task_sid = tsec->sid;
 191         inode->i_security = isec;
 192
 193         return 0;
 194 }
 195
 196 static void inode_free_security(struct inode *inode)
 197 {
 198         struct inode_security_struct *isec = inode->i_security;
 199         struct superblock_security_struct *sbsec = inode->i_sb->s_security;
 200
 201         spin_lock(&sbsec->isec_lock);
 202         if (!list_empty(&isec->list))
 203                 list_del_init(&isec->list);
 204         spin_unlock(&sbsec->isec_lock);
 205
 206         inode->i_security = NULL;
 207         kmem_cache_free(sel_inode_cache, isec);
 208 }
 209
 210 static int file_alloc_security(struct file *file)
 211 {
 212         struct task_security_struct *tsec = current->security;
 213         struct file_security_struct *fsec;
 214
 215         fsec = kzalloc(sizeof(struct file_security_struct), GFP_KERNEL);
 216         if (!fsec)
 217                 return -ENOMEM;
 218
 219         fsec->file = file;
 220         fsec->sid = tsec->sid;
 221         fsec->fown_sid = tsec->sid;
 222         file->f_security = fsec;
 223
 224         return 0;
 225 }
 226
 227 static void file_free_security(struct file *file)
 228 {
 229         struct file_security_struct *fsec = file->f_security;
 230         file->f_security = NULL;
 231         kfree(fsec);
 232 }
 233
 234 static int superblock_alloc_security(struct super_block *sb)
 235 {
 236         struct superblock_security_struct *sbsec;
 237
 238         sbsec = kzalloc(sizeof(struct superblock_security_struct), GFP_KERNEL);
 239         if (!sbsec)
 240                 return -ENOMEM;
 241
 242         init_MUTEX(&sbsec->sem);
 243         INIT_LIST_HEAD(&sbsec->list);
 244         INIT_LIST_HEAD(&sbsec->isec_head);
 245         spin_lock_init(&sbsec->isec_lock);
 246         sbsec->sb = sb;
 247         sbsec->sid = SECINITSID_UNLABELED;
 248         sbsec->def_sid = SECINITSID_FILE;
 249         sbsec->mntpoint_sid = SECINITSID_UNLABELED;
 250         sb->s_security = sbsec;
 251
 252         return 0;
 253 }
 254
 255 static void superblock_free_security(struct super_block *sb)
 256 {
 257         struct superblock_security_struct *sbsec = sb->s_security;
 258
 259         spin_lock(&sb_security_lock);
 260         if (!list_empty(&sbsec->list))
 261                 list_del_init(&sbsec->list);
 262         spin_unlock(&sb_security_lock);
 263
 264         sb->s_security = NULL;
 265         kfree(sbsec);
 266 }
 267
 268 static int sk_alloc_security(struct sock *sk, int family, gfp_t priority)
 269 {
 270         struct sk_security_struct *ssec;
 271
 272         if (family != PF_UNIX)
 273                 return 0;
 274
 275         ssec = kzalloc(sizeof(*ssec), priority);
 276         if (!ssec)
 277                 return -ENOMEM;
 278
 279         ssec->sk = sk;
 280         ssec->peer_sid = SECINITSID_UNLABELED;
 281         sk->sk_security = ssec;
 282
 283         return 0;
 284 }
 285
 286 static void sk_free_security(struct sock *sk)
 287 {
 288         struct sk_security_struct *ssec = sk->sk_security;
 289
 290         if (sk->sk_family != PF_UNIX)
 291                 return;
 292
 293         sk->sk_security = NULL;
 294         kfree(ssec);
 295 }
 296
 297 /* The security server must be initialized before
 298    any labeling or access decisions can be provided. */
 299 extern int ss_initialized;
 300
 301 /* The file system's label must be initialized prior to use. */
 302
 303 static char *labeling_behaviors[6] = {
 304         "uses xattr",
 305         "uses transition SIDs",
 306         "uses task SIDs",
 307         "uses genfs_contexts",
 308         "not configured for labeling",
 309         "uses mountpoint labeling",
 310 };
 311
 312 static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dentry);
 313
 314 static inline int inode_doinit(struct inode *inode)
 315 {
 316         return inode_doinit_with_dentry(inode, NULL);
 317 }
 318
 319 enum {
 320         Opt_context = 1,
 321         Opt_fscontext = 2,
 322         Opt_defcontext = 4,
 323         Opt_rootcontext = 8,
 324 };
 325
 326 static match_table_t tokens = {
 327         {Opt_context, "context=%s"},
 328         {Opt_fscontext, "fscontext=%s"},
 329         {Opt_defcontext, "defcontext=%s"},
 330         {Opt_rootcontext, "rootcontext=%s"},
 331 };
 332
 333 #define SEL_MOUNT_FAIL_MSG "SELinux:  duplicate or incompatible mount options\n"
 334
 335 static int may_context_mount_sb_relabel(u32 sid,
 336                         struct superblock_security_struct *sbsec,
 337                         struct task_security_struct *tsec)
 338 {
 339         int rc;
 340
 341         rc = avc_has_perm(tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM,
 342                           FILESYSTEM__RELABELFROM, NULL);
 343         if (rc)
 344                 return rc;
 345
 346         rc = avc_has_perm(tsec->sid, sid, SECCLASS_FILESYSTEM,
 347                           FILESYSTEM__RELABELTO, NULL);
 348         return rc;
 349 }
 350
 351 static int may_context_mount_inode_relabel(u32 sid,
 352                         struct superblock_security_struct *sbsec,
 353                         struct task_security_struct *tsec)
 354 {
 355         int rc;
 356         rc = avc_has_perm(tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM,
 357                           FILESYSTEM__RELABELFROM, NULL);
 358         if (rc)
 359                 return rc;
 360
 361         rc = avc_has_perm(sid, sbsec->sid, SECCLASS_FILESYSTEM,
 362                           FILESYSTEM__ASSOCIATE, NULL);
 363         return rc;
 364 }
 365
 366 static int try_context_mount(struct super_block *sb, void *data)
 367 {
 368         char *context = NULL, *defcontext = NULL;
 369         char *fscontext = NULL, *rootcontext = NULL;
 370         const char *name;
 371         u32 sid;
 372         int alloc = 0, rc = 0, seen = 0;
 373         struct task_security_struct *tsec = current->security;
 374         struct superblock_security_struct *sbsec = sb->s_security;
 375
 376         if (!data)
 377                 goto out;
 378
 379         name = sb->s_type->name;
 380
 381         if (sb->s_type->fs_flags & FS_BINARY_MOUNTDATA) {
 382
 383                 /* NFS we understand. */
 384                 if (!strcmp(name, "nfs")) {
 385                         struct nfs_mount_data *d = data;
 386
 387                         if (d->version <  NFS_MOUNT_VERSION)
 388                                 goto out;
 389
 390                         if (d->context[0]) {
 391                                 context = d->context;
 392                                 seen |= Opt_context;
 393                         }
 394                 } else
 395                         goto out;
 396
 397         } else {
 398                 /* Standard string-based options. */
 399                 char *p, *options = data;
 400
 401                 while ((p = strsep(&options, ",")) != NULL) {
 402                         int token;
 403                         substring_t args[MAX_OPT_ARGS];
 404
 405                         if (!*p)
 406                                 continue;
 407
 408                         token = match_token(p, tokens, args);
 409
 410                         switch (token) {
 411                         case Opt_context:
 412                                 if (seen & (Opt_context|Opt_defcontext)) {
 413                                         rc = -EINVAL;
 414                                         printk(KERN_WARNING SEL_MOUNT_FAIL_MSG);
 415                                         goto out_free;
 416                                 }
 417                                 context = match_strdup(&args[0]);
 418                                 if (!context) {
 419                                         rc = -ENOMEM;
 420                                         goto out_free;
 421                                 }
 422                                 if (!alloc)
 423                                         alloc = 1;
 424                                 seen |= Opt_context;
 425                                 break;
 426
 427                         case Opt_fscontext:
 428                                 if (seen & Opt_fscontext) {
 429                                         rc = -EINVAL;
 430                                         printk(KERN_WARNING SEL_MOUNT_FAIL_MSG);
 431                                         goto out_free;
 432                                 }
 433                                 fscontext = match_strdup(&args[0]);
 434                                 if (!fscontext) {
 435                                         rc = -ENOMEM;
 436                                         goto out_free;
 437                                 }
 438                                 if (!alloc)
 439                                         alloc = 1;
 440                                 seen |= Opt_fscontext;
 441                                 break;
 442
 443                         case Opt_rootcontext:
 444                                 if (seen & Opt_rootcontext) {
 445                                         rc = -EINVAL;
 446                                         printk(KERN_WARNING SEL_MOUNT_FAIL_MSG);
 447                                         goto out_free;
 448                                 }
 449                                 rootcontext = match_strdup(&args[0]);
 450                                 if (!rootcontext) {
 451                                         rc = -ENOMEM;
 452                                         goto out_free;
 453                                 }
 454                                 if (!alloc)
 455                                         alloc = 1;
 456                                 seen |= Opt_rootcontext;
 457                                 break;
 458
 459                         case Opt_defcontext:
 460                                 if (sbsec->behavior != SECURITY_FS_USE_XATTR) {
 461                                         rc = -EINVAL;
 462                                         printk(KERN_WARNING "SELinux:  "
 463                                                "defcontext option is invalid "
 464                                                "for this filesystem type\n");
 465                                         goto out_free;
 466                                 }
 467                                 if (seen & (Opt_context|Opt_defcontext)) {
 468                                         rc = -EINVAL;
 469                                         printk(KERN_WARNING SEL_MOUNT_FAIL_MSG);
 470                                         goto out_free;
 471                                 }
 472                                 defcontext = match_strdup(&args[0]);
 473                                 if (!defcontext) {
 474                                         rc = -ENOMEM;
 475                                         goto out_free;
 476                                 }
 477                                 if (!alloc)
 478                                         alloc = 1;
 479                                 seen |= Opt_defcontext;
 480                                 break;
 481
 482                         default:
 483                                 rc = -EINVAL;
 484                                 printk(KERN_WARNING "SELinux:  unknown mount "
 485                                        "option\n");
 486                                 goto out_free;
 487
 488                         }
 489                 }
 490         }
 491
 492         if (!seen)
 493                 goto out;
 494
 495         /* sets the context of the superblock for the fs being mounted. */
 496         if (fscontext) {
 497                 rc = security_context_to_sid(fscontext, strlen(fscontext), &sid);
 498                 if (rc) {
 499                         printk(KERN_WARNING "SELinux: security_context_to_sid"
 500                                "(%s) failed for (dev %s, type %s) errno=%d\n",
 501                                fscontext, sb->s_id, name, rc);
 502                         goto out_free;
 503                 }
 504
 505                 rc = may_context_mount_sb_relabel(sid, sbsec, tsec);
 506                 if (rc)
 507                         goto out_free;
 508
 509                 sbsec->sid = sid;
 510         }
 511
 512         /*
 513          * Switch to using mount point labeling behavior.
 514          * sets the label used on all file below the mountpoint, and will set
 515          * the superblock context if not already set.
 516          */
 517         if (context) {
 518                 rc = security_context_to_sid(context, strlen(context), &sid);
 519                 if (rc) {
 520                         printk(KERN_WARNING "SELinux: security_context_to_sid"
 521                                "(%s) failed for (dev %s, type %s) errno=%d\n",
 522                                context, sb->s_id, name, rc);
 523                         goto out_free;
 524                 }
 525
 526                 if (!fscontext) {
 527                         rc = may_context_mount_sb_relabel(sid, sbsec, tsec);
 528                         if (rc)
 529                                 goto out_free;
 530                         sbsec->sid = sid;
 531                 } else {
 532                         rc = may_context_mount_inode_relabel(sid, sbsec, tsec);
 533                         if (rc)
 534                                 goto out_free;
 535                 }
 536                 sbsec->mntpoint_sid = sid;
 537
 538                 sbsec->behavior = SECURITY_FS_USE_MNTPOINT;
 539         }
 540
 541         if (rootcontext) {
 542                 struct inode *inode = sb->s_root->d_inode;
 543                 struct inode_security_struct *isec = inode->i_security;
 544                 rc = security_context_to_sid(rootcontext, strlen(rootcontext), &sid);
 545                 if (rc) {
 546                         printk(KERN_WARNING "SELinux: security_context_to_sid"
 547                                "(%s) failed for (dev %s, type %s) errno=%d\n",
 548                                rootcontext, sb->s_id, name, rc);
 549                         goto out_free;
 550                 }
 551
 552                 rc = may_context_mount_inode_relabel(sid, sbsec, tsec);
 553                 if (rc)
 554                         goto out_free;
 555
 556                 isec->sid = sid;
 557                 isec->initialized = 1;
 558         }
 559
 560         if (defcontext) {
 561                 rc = security_context_to_sid(defcontext, strlen(defcontext), &sid);
 562                 if (rc) {
 563                         printk(KERN_WARNING "SELinux: security_context_to_sid"
 564                                "(%s) failed for (dev %s, type %s) errno=%d\n",
 565                                defcontext, sb->s_id, name, rc);
 566                         goto out_free;
 567                 }
 568
 569                 if (sid == sbsec->def_sid)
 570                         goto out_free;
 571
 572                 rc = may_context_mount_inode_relabel(sid, sbsec, tsec);
 573                 if (rc)
 574                         goto out_free;
 575
 576                 sbsec->def_sid = sid;
 577         }
 578
 579 out_free:
 580         if (alloc) {
 581                 kfree(context);
 582                 kfree(defcontext);
 583                 kfree(fscontext);
 584                 kfree(rootcontext);
 585         }
 586 out:
 587         return rc;
 588 }
 589
 590 static int superblock_doinit(struct super_block *sb, void *data)
 591 {
 592         struct superblock_security_struct *sbsec = sb->s_security;
 593         struct dentry *root = sb->s_root;
 594         struct inode *inode = root->d_inode;
 595         int rc = 0;
 596
 597         down(&sbsec->sem);
 598         if (sbsec->initialized)
 599                 goto out;
 600
 601         if (!ss_initialized) {
 602                 /* Defer initialization until selinux_complete_init,
 603                    after the initial policy is loaded and the security
 604                    server is ready to handle calls. */
 605                 spin_lock(&sb_security_lock);
 606                 if (list_empty(&sbsec->list))
 607                         list_add(&sbsec->list, &superblock_security_head);
 608                 spin_unlock(&sb_security_lock);
 609                 goto out;
 610         }
 611
 612         /* Determine the labeling behavior to use for this filesystem type. */
 613         rc = security_fs_use(sb->s_type->name, &sbsec->behavior, &sbsec->sid);
 614         if (rc) {
 615                 printk(KERN_WARNING "%s:  security_fs_use(%s) returned %d\n",
 616                        __FUNCTION__, sb->s_type->name, rc);
 617                 goto out;
 618         }
 619
 620         rc = try_context_mount(sb, data);
 621         if (rc)
 622                 goto out;
 623
 624         if (sbsec->behavior == SECURITY_FS_USE_XATTR) {
 625                 /* Make sure that the xattr handler exists and that no
 626                    error other than -ENODATA is returned by getxattr on
 627                    the root directory.  -ENODATA is ok, as this may be
 628                    the first boot of the SELinux kernel before we have
 629                    assigned xattr values to the filesystem. */
 630                 if (!inode->i_op->getxattr) {
 631                         printk(KERN_WARNING "SELinux: (dev %s, type %s) has no "
 632                                "xattr support\n", sb->s_id, sb->s_type->name);
 633                         rc = -EOPNOTSUPP;
 634                         goto out;
 635                 }
 636                 rc = inode->i_op->getxattr(root, XATTR_NAME_SELINUX, NULL, 0);
 637                 if (rc < 0 && rc != -ENODATA) {
 638                         if (rc == -EOPNOTSUPP)
 639                                 printk(KERN_WARNING "SELinux: (dev %s, type "
 640                                        "%s) has no security xattr handler\n",
 641                                        sb->s_id, sb->s_type->name);
 642                         else
 643                                 printk(KERN_WARNING "SELinux: (dev %s, type "
 644                                        "%s) getxattr errno %d\n", sb->s_id,
 645                                        sb->s_type->name, -rc);
 646                         goto out;
 647                 }
 648         }
 649
 650         if (strcmp(sb->s_type->name, "proc") == 0)
 651                 sbsec->proc = 1;
 652
 653         sbsec->initialized = 1;
 654
 655         if (sbsec->behavior > ARRAY_SIZE(labeling_behaviors)) {
 656                 printk(KERN_INFO "SELinux: initialized (dev %s, type %s), unknown behavior\n",
 657                        sb->s_id, sb->s_type->name);
 658         }
 659         else {
 660                 printk(KERN_INFO "SELinux: initialized (dev %s, type %s), %s\n",
 661                        sb->s_id, sb->s_type->name,
 662                        labeling_behaviors[sbsec->behavior-1]);
 663         }
 664
 665         /* Initialize the root inode. */
 666         rc = inode_doinit_with_dentry(sb->s_root->d_inode, sb->s_root);
 667
 668         /* Initialize any other inodes associated with the superblock, e.g.
 669            inodes created prior to initial policy load or inodes created
 670            during get_sb by a pseudo filesystem that directly
 671            populates itself. */
 672         spin_lock(&sbsec->isec_lock);
 673 next_inode:
 674         if (!list_empty(&sbsec->isec_head)) {
 675                 struct inode_security_struct *isec =
 676                                 list_entry(sbsec->isec_head.next,
 677                                            struct inode_security_struct, list);
 678                 struct inode *inode = isec->inode;
 679                 spin_unlock(&sbsec->isec_lock);
 680                 inode = igrab(inode);
 681                 if (inode) {
 682                         if (!IS_PRIVATE (inode))
 683                                 inode_doinit(inode);
 684                         iput(inode);
 685                 }
 686                 spin_lock(&sbsec->isec_lock);
 687                 list_del_init(&isec->list);
 688                 goto next_inode;
 689         }
 690         spin_unlock(&sbsec->isec_lock);
 691 out:
 692         up(&sbsec->sem);
 693         return rc;
 694 }
 695
 696 static inline u16 inode_mode_to_security_class(umode_t mode)
 697 {
 698         switch (mode & S_IFMT) {
 699         case S_IFSOCK:
 700                 return SECCLASS_SOCK_FILE;
 701         case S_IFLNK:
 702                 return SECCLASS_LNK_FILE;
 703         case S_IFREG:
 704                 return SECCLASS_FILE;
 705         case S_IFBLK:
 706                 return SECCLASS_BLK_FILE;
 707         case S_IFDIR:
 708                 return SECCLASS_DIR;
 709         case S_IFCHR:
 710                 return SECCLASS_CHR_FILE;
 711         case S_IFIFO:
 712                 return SECCLASS_FIFO_FILE;
 713
 714         }
 715
 716         return SECCLASS_FILE;
 717 }
 718
 719 static inline int default_protocol_stream(int protocol)
 720 {
 721         return (protocol == IPPROTO_IP || protocol == IPPROTO_TCP);
 722 }
 723
 724 static inline int default_protocol_dgram(int protocol)
 725 {
 726         return (protocol == IPPROTO_IP || protocol == IPPROTO_UDP);
 727 }
 728
 729 static inline u16 socket_type_to_security_class(int family, int type, int protocol)
 730 {
 731         switch (family) {
 732         case PF_UNIX:
 733                 switch (type) {
 734                 case SOCK_STREAM:
 735                 case SOCK_SEQPACKET:
 736                         return SECCLASS_UNIX_STREAM_SOCKET;
 737                 case SOCK_DGRAM:
 738                         return SECCLASS_UNIX_DGRAM_SOCKET;
 739                 }
 740                 break;
 741         case PF_INET:
 742         case PF_INET6:
 743                 switch (type) {
 744                 case SOCK_STREAM:
 745                         if (default_protocol_stream(protocol))
 746                                 return SECCLASS_TCP_SOCKET;
 747                         else
 748                                 return SECCLASS_RAWIP_SOCKET;
 749                 case SOCK_DGRAM:
 750                         if (default_protocol_dgram(protocol))
 751                                 return SECCLASS_UDP_SOCKET;
 752                         else
 753                                 return SECCLASS_RAWIP_SOCKET;
 754                 default:
 755                         return SECCLASS_RAWIP_SOCKET;
 756                 }
 757                 break;
 758         case PF_NETLINK:
 759                 switch (protocol) {
 760                 case NETLINK_ROUTE:
 761                         return SECCLASS_NETLINK_ROUTE_SOCKET;
 762                 case NETLINK_FIREWALL:
 763                         return SECCLASS_NETLINK_FIREWALL_SOCKET;
 764                 case NETLINK_INET_DIAG:
 765                         return SECCLASS_NETLINK_TCPDIAG_SOCKET;
 766                 case NETLINK_NFLOG:
 767                         return SECCLASS_NETLINK_NFLOG_SOCKET;
 768                 case NETLINK_XFRM:
 769                         return SECCLASS_NETLINK_XFRM_SOCKET;
 770                 case NETLINK_SELINUX:
 771                         return SECCLASS_NETLINK_SELINUX_SOCKET;
 772                 case NETLINK_AUDIT:
 773                         return SECCLASS_NETLINK_AUDIT_SOCKET;
 774                 case NETLINK_IP6_FW:
 775                         return SECCLASS_NETLINK_IP6FW_SOCKET;
 776                 case NETLINK_DNRTMSG:
 777                         return SECCLASS_NETLINK_DNRT_SOCKET;
 778                 case NETLINK_KOBJECT_UEVENT:
 779                         return SECCLASS_NETLINK_KOBJECT_UEVENT_SOCKET;
 780                 default:
 781                         return SECCLASS_NETLINK_SOCKET;
 782                 }
 783         case PF_PACKET:
 784                 return SECCLASS_PACKET_SOCKET;
 785         case PF_KEY:
 786                 return SECCLASS_KEY_SOCKET;
 787         case PF_APPLETALK:
 788                 return SECCLASS_APPLETALK_SOCKET;
 789         }
 790
 791         return SECCLASS_SOCKET;
 792 }
 793
 794 #ifdef CONFIG_PROC_FS
 795 static int selinux_proc_get_sid(struct proc_dir_entry *de,
 796                                 u16 tclass,
 797                                 u32 *sid)
 798 {
 799         int buflen, rc;
 800         char *buffer, *path, *end;
 801
 802         buffer = (char*)__get_free_page(GFP_KERNEL);
 803         if (!buffer)
 804                 return -ENOMEM;
 805
 806         buflen = PAGE_SIZE;
 807         end = buffer+buflen;
 808         *--end = '\0';
 809         buflen--;
 810         path = end-1;
 811         *path = '/';
 812         while (de && de != de->parent) {
 813                 buflen -= de->namelen + 1;
 814                 if (buflen < 0)
 815                         break;
 816                 end -= de->namelen;
 817                 memcpy(end, de->name, de->namelen);
 818                 *--end = '/';
 819                 path = end;
 820                 de = de->parent;
 821         }
 822         rc = security_genfs_sid("proc", path, tclass, sid);
 823         free_page((unsigned long)buffer);
 824         return rc;
 825 }
 826 #else
 827 static int selinux_proc_get_sid(struct proc_dir_entry *de,
 828                                 u16 tclass,
 829                                 u32 *sid)
 830 {
 831         return -EINVAL;
 832 }
 833 #endif
 834
 835 /* The inode's security attributes must be initialized before first use. */
 836 static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dentry)
 837 {
 838         struct superblock_security_struct *sbsec = NULL;
 839         struct inode_security_struct *isec = inode->i_security;
 840         u32 sid;
 841         struct dentry *dentry;
 842 #define INITCONTEXTLEN 255
 843         char *context = NULL;
 844         unsigned len = 0;
 845         int rc = 0;
 846         int hold_sem = 0;
 847
 848         if (isec->initialized)
 849                 goto out;
 850
 851         down(&isec->sem);
 852         hold_sem = 1;
 853         if (isec->initialized)
 854                 goto out;
 855
 856         sbsec = inode->i_sb->s_security;
 857         if (!sbsec->initialized) {
 858                 /* Defer initialization until selinux_complete_init,
 859                    after the initial policy is loaded and the security
 860                    server is ready to handle calls. */
 861                 spin_lock(&sbsec->isec_lock);
 862                 if (list_empty(&isec->list))
 863                         list_add(&isec->list, &sbsec->isec_head);
 864                 spin_unlock(&sbsec->isec_lock);
 865                 goto out;
 866         }
 867
 868         switch (sbsec->behavior) {
 869         case SECURITY_FS_USE_XATTR:
 870                 if (!inode->i_op->getxattr) {
 871                         isec->sid = sbsec->def_sid;
 872                         break;
 873                 }
 874
 875                 /* Need a dentry, since the xattr API requires one.
 876                    Life would be simpler if we could just pass the inode. */
 877                 if (opt_dentry) {
 878                         /* Called from d_instantiate or d_splice_alias. */
 879                         dentry = dget(opt_dentry);
 880                 } else {
 881                         /* Called from selinux_complete_init, try to find a dentry. */
 882                         dentry = d_find_alias(inode);
 883                 }
 884                 if (!dentry) {
 885                         printk(KERN_WARNING "%s:  no dentry for dev=%s "
 886                                "ino=%ld\n", __FUNCTION__, inode->i_sb->s_id,
 887                                inode->i_ino);
 888                         goto out;
 889                 }
 890
 891                 len = INITCONTEXTLEN;
 892                 context = kmalloc(len, GFP_KERNEL);
 893                 if (!context) {
 894                         rc = -ENOMEM;
 895                         dput(dentry);
 896                         goto out;
 897                 }
 898                 rc = inode->i_op->getxattr(dentry, XATTR_NAME_SELINUX,
 899                                            context, len);
 900                 if (rc == -ERANGE) {
 901                         /* Need a larger buffer.  Query for the right size. */
 902                         rc = inode->i_op->getxattr(dentry, XATTR_NAME_SELINUX,
 903                                                    NULL, 0);
 904                         if (rc < 0) {
 905                                 dput(dentry);
 906                                 goto out;
 907                         }
 908                         kfree(context);
 909                         len = rc;
 910                         context = kmalloc(len, GFP_KERNEL);
 911                         if (!context) {
 912                                 rc = -ENOMEM;
 913                                 dput(dentry);
 914                                 goto out;
 915                         }
 916                         rc = inode->i_op->getxattr(dentry,
 917                                                    XATTR_NAME_SELINUX,
 918                                                    context, len);
 919                 }
 920                 dput(dentry);
 921                 if (rc < 0) {
 922                         if (rc != -ENODATA) {
 923                                 printk(KERN_WARNING "%s:  getxattr returned "
 924                                        "%d for dev=%s ino=%ld\n", __FUNCTION__,
 925                                        -rc, inode->i_sb->s_id, inode->i_ino);
 926                                 kfree(context);
 927                                 goto out;
 928                         }
 929                         /* Map ENODATA to the default file SID */
 930                         sid = sbsec->def_sid;
 931                         rc = 0;
 932                 } else {
 933                         rc = security_context_to_sid_default(context, rc, &sid,
 934                                                              sbsec->def_sid);
 935                         if (rc) {
 936                                 printk(KERN_WARNING "%s:  context_to_sid(%s) "
 937                                        "returned %d for dev=%s ino=%ld\n",
 938                                        __FUNCTION__, context, -rc,
 939                                        inode->i_sb->s_id, inode->i_ino);
 940                                 kfree(context);
 941                                 /* Leave with the unlabeled SID */
 942                                 rc = 0;
 943                                 break;
 944                         }
 945                 }
 946                 kfree(context);
 947                 isec->sid = sid;
 948                 break;
 949         case SECURITY_FS_USE_TASK:
 950                 isec->sid = isec->task_sid;
 951                 break;
 952         case SECURITY_FS_USE_TRANS:
 953                 /* Default to the fs SID. */
 954                 isec->sid = sbsec->sid;
 955
 956                 /* Try to obtain a transition SID. */
 957                 isec->sclass = inode_mode_to_security_class(inode->i_mode);
 958                 rc = security_transition_sid(isec->task_sid,
 959                                              sbsec->sid,
 960                                              isec->sclass,
 961                                              &sid);
 962                 if (rc)
 963                         goto out;
 964                 isec->sid = sid;
 965                 break;
 966         case SECURITY_FS_USE_MNTPOINT:
 967                 isec->sid = sbsec->mntpoint_sid;
 968                 break;
 969         default:
 970                 /* Default to the fs superblock SID. */
 971                 isec->sid = sbsec->sid;
 972
 973                 if (sbsec->proc) {
 974                         struct proc_inode *proci = PROC_I(inode);
 975                         if (proci->pde) {
 976                                 isec->sclass = inode_mode_to_security_class(inode->i_mode);
 977                                 rc = selinux_proc_get_sid(proci->pde,
 978                                                           isec->sclass,
 979                                                           &sid);
 980                                 if (rc)
 981                                         goto out;
 982                                 isec->sid = sid;
 983                         }
 984                 }
 985                 break;
 986         }
 987
 988         isec->initialized = 1;
 989
 990 out:
 991         if (isec->sclass == SECCLASS_FILE)
 992                 isec->sclass = inode_mode_to_security_class(inode->i_mode);
 993
 994         if (hold_sem)
 995                 up(&isec->sem);
 996         return rc;
 997 }
 998
 999 /* Convert a Linux signal to an access vector. */
1000 static inline u32 signal_to_av(int sig)
1001 {
1002         u32 perm = 0;
1003
1004         switch (sig) {
1005         case SIGCHLD:
1006                 /* Commonly granted from child to parent. */
1007                 perm = PROCESS__SIGCHLD;
1008                 break;
1009         case SIGKILL:
1010                 /* Cannot be caught or ignored */
1011                 perm = PROCESS__SIGKILL;
1012                 break;
1013         case SIGSTOP:
1014                 /* Cannot be caught or ignored */
1015                 perm = PROCESS__SIGSTOP;
1016                 break;
1017         default:
1018                 /* All other signals. */
1019                 perm = PROCESS__SIGNAL;
1020                 break;
1021         }
1022
1023         return perm;
1024 }
1025
1026 /* Check permission betweeen a pair of tasks, e.g. signal checks,
1027    fork check, ptrace check, etc. */
1028 static int task_has_perm(struct task_struct *tsk1,
1029                          struct task_struct *tsk2,
1030                          u32 perms)
1031 {
1032         struct task_security_struct *tsec1, *tsec2;
1033
1034         tsec1 = tsk1->security;
1035         tsec2 = tsk2->security;
1036         return avc_has_perm(tsec1->sid, tsec2->sid,
1037                             SECCLASS_PROCESS, perms, NULL);
1038 }
1039
1040 /* Check whether a task is allowed to use a capability. */
1041 static int task_has_capability(struct task_struct *tsk,
1042                                int cap)
1043 {
1044         struct task_security_struct *tsec;
1045         struct avc_audit_data ad;
1046
1047         tsec = tsk->security;
1048
1049         AVC_AUDIT_DATA_INIT(&ad,CAP);
1050         ad.tsk = tsk;
1051         ad.u.cap = cap;
1052
1053         return avc_has_perm(tsec->sid, tsec->sid,
1054                             SECCLASS_CAPABILITY, CAP_TO_MASK(cap), &ad);
1055 }
1056
1057 /* Check whether a task is allowed to use a system operation. */
1058 static int task_has_system(struct task_struct *tsk,
1059                            u32 perms)
1060 {
1061         struct task_security_struct *tsec;
1062
1063         tsec = tsk->security;
1064
1065         return avc_has_perm(tsec->sid, SECINITSID_KERNEL,
1066                             SECCLASS_SYSTEM, perms, NULL);
1067 }
1068
1069 /* Check whether a task has a particular permission to an inode.
1070    The 'adp' parameter is optional and allows other audit
1071    data to be passed (e.g. the dentry). */
1072 static int inode_has_perm(struct task_struct *tsk,
1073                           struct inode *inode,
1074                           u32 perms,
1075                           struct avc_audit_data *adp)
1076 {
1077         struct task_security_struct *tsec;
1078         struct inode_security_struct *isec;
1079         struct avc_audit_data ad;
1080
1081         tsec = tsk->security;
1082         isec = inode->i_security;
1083
1084         if (!adp) {
1085                 adp = &ad;
1086                 AVC_AUDIT_DATA_INIT(&ad, FS);
1087                 ad.u.fs.inode = inode;
1088         }
1089
1090         return avc_has_perm(tsec->sid, isec->sid, isec->sclass, perms, adp);
1091 }
1092
1093 /* Same as inode_has_perm, but pass explicit audit data containing
1094    the dentry to help the auditing code to more easily generate the
1095    pathname if needed. */
1096 static inline int dentry_has_perm(struct task_struct *tsk,
1097                                   struct vfsmount *mnt,
1098                                   struct dentry *dentry,
1099                                   u32 av)
1100 {
1101         struct inode *inode = dentry->d_inode;
1102         struct avc_audit_data ad;
1103         AVC_AUDIT_DATA_INIT(&ad,FS);
1104         ad.u.fs.mnt = mnt;
1105         ad.u.fs.dentry = dentry;
1106         return inode_has_perm(tsk, inode, av, &ad);
1107 }
1108
1109 /* Check whether a task can use an open file descriptor to
1110    access an inode in a given way.  Check access to the
1111    descriptor itself, and then use dentry_has_perm to
1112    check a particular permission to the file.
1113    Access to the descriptor is implicitly granted if it
1114    has the same SID as the process.  If av is zero, then
1115    access to the file is not checked, e.g. for cases
1116    where only the descriptor is affected like seek. */
1117 static int file_has_perm(struct task_struct *tsk,
1118                                 struct file *file,
1119                                 u32 av)
1120 {
1121         struct task_security_struct *tsec = tsk->security;
1122         struct file_security_struct *fsec = file->f_security;
1123         struct vfsmount *mnt = file->f_vfsmnt;
1124         struct dentry *dentry = file->f_dentry;
1125         struct inode *inode = dentry->d_inode;
1126         struct avc_audit_data ad;
1127         int rc;
1128
1129         AVC_AUDIT_DATA_INIT(&ad, FS);
1130         ad.u.fs.mnt = mnt;
1131         ad.u.fs.dentry = dentry;
1132
1133         if (tsec->sid != fsec->sid) {
1134                 rc = avc_has_perm(tsec->sid, fsec->sid,
1135                                   SECCLASS_FD,
1136                                   FD__USE,
1137                                   &ad);
1138                 if (rc)
1139                         return rc;
1140         }
1141
1142         /* av is zero if only checking access to the descriptor. */
1143         if (av)
1144                 return inode_has_perm(tsk, inode, av, &ad);
1145
1146         return 0;
1147 }
1148
1149 /* Check whether a task can create a file. */
1150 static int may_create(struct inode *dir,
1151                       struct dentry *dentry,
1152                       u16 tclass)
1153 {
1154         struct task_security_struct *tsec;
1155         struct inode_security_struct *dsec;
1156         struct superblock_security_struct *sbsec;
1157         u32 newsid;
1158         struct avc_audit_data ad;
1159         int rc;
1160
1161         tsec = current->security;
1162         dsec = dir->i_security;
1163         sbsec = dir->i_sb->s_security;
1164
1165         AVC_AUDIT_DATA_INIT(&ad, FS);
1166         ad.u.fs.dentry = dentry;
1167
1168         rc = avc_has_perm(tsec->sid, dsec->sid, SECCLASS_DIR,
1169                           DIR__ADD_NAME | DIR__SEARCH,
1170                           &ad);
1171         if (rc)
1172                 return rc;
1173
1174         if (tsec->create_sid && sbsec->behavior != SECURITY_FS_USE_MNTPOINT) {
1175                 newsid = tsec->create_sid;
1176         } else {
1177                 rc = security_transition_sid(tsec->sid, dsec->sid, tclass,
1178                                              &newsid);
1179                 if (rc)
1180                         return rc;
1181         }
1182
1183         rc = avc_has_perm(tsec->sid, newsid, tclass, FILE__CREATE, &ad);
1184         if (rc)
1185                 return rc;
1186
1187         return avc_has_perm(newsid, sbsec->sid,
1188                             SECCLASS_FILESYSTEM,
1189                             FILESYSTEM__ASSOCIATE, &ad);
1190 }
1191
1192 /* Check whether a task can create a key. */
1193 static int may_create_key(u32 ksid,
1194                           struct task_struct *ctx)
1195 {
1196         struct task_security_struct *tsec;
1197
1198         tsec = ctx->security;
1199
1200         return avc_has_perm(tsec->sid, ksid, SECCLASS_KEY, KEY__CREATE, NULL);
1201 }
1202
1203 #define MAY_LINK   0
1204 #define MAY_UNLINK 1
1205 #define MAY_RMDIR  2
1206
1207 /* Check whether a task can link, unlink, or rmdir a file/directory. */
1208 static int may_link(struct inode *dir,
1209                     struct dentry *dentry,
1210                     int kind)
1211
1212 {
1213         struct task_security_struct *tsec;
1214         struct inode_security_struct *dsec, *isec;
1215         struct avc_audit_data ad;
1216         u32 av;
1217         int rc;
1218
1219         tsec = current->security;
1220         dsec = dir->i_security;
1221         isec = dentry->d_inode->i_security;
1222
1223         AVC_AUDIT_DATA_INIT(&ad, FS);
1224         ad.u.fs.dentry = dentry;
1225
1226         av = DIR__SEARCH;
1227         av |= (kind ? DIR__REMOVE_NAME : DIR__ADD_NAME);
1228         rc = avc_has_perm(tsec->sid, dsec->sid, SECCLASS_DIR, av, &ad);
1229         if (rc)
1230                 return rc;
1231
1232         switch (kind) {
1233         case MAY_LINK:
1234                 av = FILE__LINK;
1235                 break;
1236         case MAY_UNLINK:
1237                 av = FILE__UNLINK;
1238                 break;
1239         case MAY_RMDIR:
1240                 av = DIR__RMDIR;
1241                 break;
1242         default:
1243                 printk(KERN_WARNING "may_link:  unrecognized kind %d\n", kind);
1244                 return 0;
1245         }
1246
1247         rc = avc_has_perm(tsec->sid, isec->sid, isec->sclass, av, &ad);
1248         return rc;
1249 }
1250
1251 static inline int may_rename(struct inode *old_dir,
1252                              struct dentry *old_dentry,
1253                              struct inode *new_dir,
1254                              struct dentry *new_dentry)
1255 {
1256         struct task_security_struct *tsec;
1257         struct inode_security_struct *old_dsec, *new_dsec, *old_isec, *new_isec;
1258         struct avc_audit_data ad;
1259         u32 av;
1260         int old_is_dir, new_is_dir;
1261         int rc;
1262
1263         tsec = current->security;
1264         old_dsec = old_dir->i_security;
1265         old_isec = old_dentry->d_inode->i_security;
1266         old_is_dir = S_ISDIR(old_dentry->d_inode->i_mode);
1267         new_dsec = new_dir->i_security;
1268
1269         AVC_AUDIT_DATA_INIT(&ad, FS);
1270
1271         ad.u.fs.dentry = old_dentry;
1272         rc = avc_has_perm(tsec->sid, old_dsec->sid, SECCLASS_DIR,
1273                           DIR__REMOVE_NAME | DIR__SEARCH, &ad);
1274         if (rc)
1275                 return rc;
1276         rc = avc_has_perm(tsec->sid, old_isec->sid,
1277                           old_isec->sclass, FILE__RENAME, &ad);
1278         if (rc)
1279                 return rc;
1280         if (old_is_dir && new_dir != old_dir) {
1281                 rc = avc_has_perm(tsec->sid, old_isec->sid,
1282                                   old_isec->sclass, DIR__REPARENT, &ad);
1283                 if (rc)
1284                         return rc;
1285         }
1286
1287         ad.u.fs.dentry = new_dentry;
1288         av = DIR__ADD_NAME | DIR__SEARCH;
1289         if (new_dentry->d_inode)
1290                 av |= DIR__REMOVE_NAME;
1291         rc = avc_has_perm(tsec->sid, new_dsec->sid, SECCLASS_DIR, av, &ad);
1292         if (rc)
1293                 return rc;
1294         if (new_dentry->d_inode) {
1295                 new_isec = new_dentry->d_inode->i_security;
1296                 new_is_dir = S_ISDIR(new_dentry->d_inode->i_mode);
1297                 rc = avc_has_perm(tsec->sid, new_isec->sid,
1298                                   new_isec->sclass,
1299                                   (new_is_dir ? DIR__RMDIR : FILE__UNLINK), &ad);
1300                 if (rc)
1301                         return rc;
1302         }
1303
1304         return 0;
1305 }
1306
1307 /* Check whether a task can perform a filesystem operation. */
1308 static int superblock_has_perm(struct task_struct *tsk,
1309                                struct super_block *sb,
1310                                u32 perms,
1311                                struct avc_audit_data *ad)
1312 {
1313         struct task_security_struct *tsec;
1314         struct superblock_security_struct *sbsec;
1315
1316         tsec = tsk->security;
1317         sbsec = sb->s_security;
1318         return avc_has_perm(tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM,
1319                             perms, ad);
1320 }
1321
1322 /* Convert a Linux mode and permission mask to an access vector. */
1323 static inline u32 file_mask_to_av(int mode, int mask)
1324 {
1325         u32 av = 0;
1326
1327         if ((mode & S_IFMT) != S_IFDIR) {
1328                 if (mask & MAY_EXEC)
1329                         av |= FILE__EXECUTE;
1330                 if (mask & MAY_READ)
1331                         av |= FILE__READ;
1332
1333                 if (mask & MAY_APPEND)
1334                         av |= FILE__APPEND;
1335                 else if (mask & MAY_WRITE)
1336                         av |= FILE__WRITE;
1337
1338         } else {
1339                 if (mask & MAY_EXEC)
1340                         av |= DIR__SEARCH;
1341                 if (mask & MAY_WRITE)
1342                         av |= DIR__WRITE;
1343                 if (mask & MAY_READ)
1344                         av |= DIR__READ;
1345         }
1346
1347         return av;
1348 }
1349
1350 /* Convert a Linux file to an access vector. */
1351 static inline u32 file_to_av(struct file *file)
1352 {
1353         u32 av = 0;
1354
1355         if (file->f_mode & FMODE_READ)
1356                 av |= FILE__READ;
1357         if (file->f_mode & FMODE_WRITE) {
1358                 if (file->f_flags & O_APPEND)
1359                         av |= FILE__APPEND;
1360                 else
1361                         av |= FILE__WRITE;
1362         }
1363
1364         return av;
1365 }
1366
1367 /* Set an inode's SID to a specified value. */
1368 static int inode_security_set_sid(struct inode *inode, u32 sid)
1369 {
1370         struct inode_security_struct *isec = inode->i_security;
1371         struct superblock_security_struct *sbsec = inode->i_sb->s_security;
1372
1373         if (!sbsec->initialized) {
1374                 /* Defer initialization to selinux_complete_init. */
1375                 return 0;
1376         }
1377
1378         down(&isec->sem);
1379         isec->sclass = inode_mode_to_security_class(inode->i_mode);
1380         isec->sid = sid;
1381         isec->initialized = 1;
1382         up(&isec->sem);
1383         return 0;
1384 }
1385
1386 /* Hook functions begin here. */
1387
1388 static int selinux_ptrace(struct task_struct *parent, struct task_struct *child)
1389 {
1390         struct task_security_struct *psec = parent->security;
1391         struct task_security_struct *csec = child->security;
1392         int rc;
1393
1394         rc = secondary_ops->ptrace(parent,child);
1395         if (rc)
1396                 return rc;
1397
1398         rc = task_has_perm(parent, child, PROCESS__PTRACE);
1399         /* Save the SID of the tracing process for later use in apply_creds. */
1400         if (!(child->ptrace & PT_PTRACED) && !rc)
1401                 csec->ptrace_sid = psec->sid;
1402         return rc;
1403 }
1404
1405 static int selinux_capget(struct task_struct *target, kernel_cap_t *effective,
1406                           kernel_cap_t *inheritable, kernel_cap_t *permitted)
1407 {
1408         int error;
1409
1410         error = task_has_perm(current, target, PROCESS__GETCAP);
1411         if (error)
1412                 return error;
1413
1414         return secondary_ops->capget(target, effective, inheritable, permitted);
1415 }
1416
1417 static int selinux_capset_check(struct task_struct *target, kernel_cap_t *effective,
1418                                 kernel_cap_t *inheritable, kernel_cap_t *permitted)
1419 {
1420         int error;
1421
1422         error = secondary_ops->capset_check(target, effective, inheritable, permitted);
1423         if (error)
1424                 return error;
1425
1426         return task_has_perm(current, target, PROCESS__SETCAP);
1427 }
1428
1429 static void selinux_capset_set(struct task_struct *target, kernel_cap_t *effective,
1430                                kernel_cap_t *inheritable, kernel_cap_t *permitted)
1431 {
1432         secondary_ops->capset_set(target, effective, inheritable, permitted);
1433 }
1434
1435 static int selinux_capable(struct task_struct *tsk, int cap)
1436 {
1437         int rc;
1438
1439         rc = secondary_ops->capable(tsk, cap);
1440         if (rc)
1441                 return rc;
1442
1443         return task_has_capability(tsk,cap);
1444 }
1445
1446 static int selinux_sysctl(ctl_table *table, int op)
1447 {
1448         int error = 0;
1449         u32 av;
1450         struct task_security_struct *tsec;
1451         u32 tsid;
1452         int rc;
1453
1454         rc = secondary_ops->sysctl(table, op);
1455         if (rc)
1456                 return rc;
1457
1458         tsec = current->security;
1459
1460         rc = selinux_proc_get_sid(table->de, (op == 001) ?
1461                                   SECCLASS_DIR : SECCLASS_FILE, &tsid);
1462         if (rc) {
1463                 /* Default to the well-defined sysctl SID. */
1464                 tsid = SECINITSID_SYSCTL;
1465         }
1466
1467         /* The op values are "defined" in sysctl.c, thereby creating
1468          * a bad coupling between this module and sysctl.c */
1469         if(op == 001) {
1470                 error = avc_has_perm(tsec->sid, tsid,
1471                                      SECCLASS_DIR, DIR__SEARCH, NULL);
1472         } else {
1473                 av = 0;
1474                 if (op & 004)
1475                         av |= FILE__READ;
1476                 if (op & 002)
1477                         av |= FILE__WRITE;
1478                 if (av)
1479                         error = avc_has_perm(tsec->sid, tsid,
1480                                              SECCLASS_FILE, av, NULL);
1481         }
1482
1483         return error;
1484 }
1485
1486 static int selinux_quotactl(int cmds, int type, int id, struct super_block *sb)
1487 {
1488         int rc = 0;
1489
1490         if (!sb)
1491                 return 0;
1492
1493         switch (cmds) {
1494                 case Q_SYNC:
1495                 case Q_QUOTAON:
1496                 case Q_QUOTAOFF:
1497                 case Q_SETINFO:
1498                 case Q_SETQUOTA:
1499                         rc = superblock_has_perm(current,
1500                                                  sb,
1501                                                  FILESYSTEM__QUOTAMOD, NULL);
1502                         break;
1503                 case Q_GETFMT:
1504                 case Q_GETINFO:
1505                 case Q_GETQUOTA:
1506                         rc = superblock_has_perm(current,
1507                                                  sb,
1508                                                  FILESYSTEM__QUOTAGET, NULL);
1509                         break;
1510                 default:
1511                         rc = 0;  /* let the kernel handle invalid cmds */
1512                         break;
1513         }
1514         return rc;
1515 }
1516
1517 static int selinux_quota_on(struct dentry *dentry)
1518 {
1519         return dentry_has_perm(current, NULL, dentry, FILE__QUOTAON);
1520 }
1521
1522 static int selinux_syslog(int type)
1523 {
1524         int rc;
1525
1526         rc = secondary_ops->syslog(type);
1527         if (rc)
1528                 return rc;
1529
1530         switch (type) {
1531                 case 3:         /* Read last kernel messages */
1532                 case 10:        /* Return size of the log buffer */
1533                         rc = task_has_system(current, SYSTEM__SYSLOG_READ);
1534                         break;
1535                 case 6:         /* Disable logging to console */
1536                 case 7:         /* Enable logging to console */
1537                 case 8:         /* Set level of messages printed to console */
1538                         rc = task_has_system(current, SYSTEM__SYSLOG_CONSOLE);
1539                         break;
1540                 case 0:         /* Close log */
1541                 case 1:         /* Open log */
1542                 case 2:         /* Read from log */
1543                 case 4:         /* Read/clear last kernel messages */
1544                 case 5:         /* Clear ring buffer */
1545                 default:
1546                         rc = task_has_system(current, SYSTEM__SYSLOG_MOD);
1547                         break;
1548         }
1549         return rc;
1550 }
1551
1552 /*
1553  * Check that a process has enough memory to allocate a new virtual
1554  * mapping. 0 means there is enough memory for the allocation to
1555  * succeed and -ENOMEM implies there is not.
1556  *
1557  * Note that secondary_ops->capable and task_has_perm_noaudit return 0
1558  * if the capability is granted, but __vm_enough_memory requires 1 if
1559  * the capability is granted.
1560  *
1561  * Do not audit the selinux permission check, as this is applied to all
1562  * processes that allocate mappings.
1563  */
1564 static int selinux_vm_enough_memory(long pages)
1565 {
1566         int rc, cap_sys_admin = 0;
1567         struct task_security_struct *tsec = current->security;
1568
1569         rc = secondary_ops->capable(current, CAP_SYS_ADMIN);
1570         if (rc == 0)
1571                 rc = avc_has_perm_noaudit(tsec->sid, tsec->sid,
1572                                         SECCLASS_CAPABILITY,
1573                                         CAP_TO_MASK(CAP_SYS_ADMIN),
1574                                         NULL);
1575
1576         if (rc == 0)
1577                 cap_sys_admin = 1;
1578
1579         return __vm_enough_memory(pages, cap_sys_admin);
1580 }
1581
1582 /* binprm security operations */
1583
1584 static int selinux_bprm_alloc_security(struct linux_binprm *bprm)
1585 {
1586         struct bprm_security_struct *bsec;
1587
1588         bsec = kzalloc(sizeof(struct bprm_security_struct), GFP_KERNEL);
1589         if (!bsec)
1590                 return -ENOMEM;
1591
1592         bsec->bprm = bprm;
1593         bsec->sid = SECINITSID_UNLABELED;
1594         bsec->set = 0;
1595
1596         bprm->security = bsec;
1597         return 0;
1598 }
1599
1600 static int selinux_bprm_set_security(struct linux_binprm *bprm)
1601 {
1602         struct task_security_struct *tsec;
1603         struct inode *inode = bprm->file->f_dentry->d_inode;
1604         struct inode_security_struct *isec;
1605         struct bprm_security_struct *bsec;
1606         u32 newsid;
1607         struct avc_audit_data ad;
1608         int rc;
1609
1610         rc = secondary_ops->bprm_set_security(bprm);
1611         if (rc)
1612                 return rc;
1613
1614         bsec = bprm->security;
1615
1616         if (bsec->set)
1617                 return 0;
1618
1619         tsec = current->security;
1620         isec = inode->i_security;
1621
1622         /* Default to the current task SID. */
1623         bsec->sid = tsec->sid;
1624
1625         /* Reset fs, key, and sock SIDs on execve. */
1626         tsec->create_sid = 0;
1627         tsec->keycreate_sid = 0;
1628         tsec->sockcreate_sid = 0;
1629
1630         if (tsec->exec_sid) {
1631                 newsid = tsec->exec_sid;
1632                 /* Reset exec SID on execve. */
1633                 tsec->exec_sid = 0;
1634         } else {
1635                 /* Check for a default transition on this program. */
1636                 rc = security_transition_sid(tsec->sid, isec->sid,
1637                                              SECCLASS_PROCESS, &newsid);
1638                 if (rc)
1639                         return rc;
1640         }
1641
1642         AVC_AUDIT_DATA_INIT(&ad, FS);
1643         ad.u.fs.mnt = bprm->file->f_vfsmnt;
1644         ad.u.fs.dentry = bprm->file->f_dentry;
1645
1646         if (bprm->file->f_vfsmnt->mnt_flags & MNT_NOSUID)
1647                 newsid = tsec->sid;
1648
1649         if (tsec->sid == newsid) {
1650                 rc = avc_has_perm(tsec->sid, isec->sid,
1651                                   SECCLASS_FILE, FILE__EXECUTE_NO_TRANS, &ad);
1652                 if (rc)
1653                         return rc;
1654         } else {
1655                 /* Check permissions for the transition. */
1656                 rc = avc_has_perm(tsec->sid, newsid,
1657                                   SECCLASS_PROCESS, PROCESS__TRANSITION, &ad);
1658                 if (rc)
1659                         return rc;
1660
1661                 rc = avc_has_perm(newsid, isec->sid,
1662                                   SECCLASS_FILE, FILE__ENTRYPOINT, &ad);
1663                 if (rc)
1664                         return rc;
1665
1666                 /* Clear any possibly unsafe personality bits on exec: */
1667                 current->personality &= ~PER_CLEAR_ON_SETID;
1668
1669                 /* Set the security field to the new SID. */
1670                 bsec->sid = newsid;
1671         }
1672
1673         bsec->set = 1;
1674         return 0;
1675 }
1676
1677 static int selinux_bprm_check_security (struct linux_binprm *bprm)
1678 {
1679         return secondary_ops->bprm_check_security(bprm);
1680 }
1681
1682
1683 static int selinux_bprm_secureexec (struct linux_binprm *bprm)
1684 {
1685         struct task_security_struct *tsec = current->security;
1686         int atsecure = 0;
1687
1688         if (tsec->osid != tsec->sid) {
1689                 /* Enable secure mode for SIDs transitions unless
1690                    the noatsecure permission is granted between
1691                    the two SIDs, i.e. ahp returns 0. */
1692                 atsecure = avc_has_perm(tsec->osid, tsec->sid,
1693                                          SECCLASS_PROCESS,
1694                                          PROCESS__NOATSECURE, NULL);
1695         }
1696
1697         return (atsecure || secondary_ops->bprm_secureexec(bprm));
1698 }
1699
1700 static void selinux_bprm_free_security(struct linux_binprm *bprm)
1701 {
1702         kfree(bprm->security);
1703         bprm->security = NULL;
1704 }
1705
1706 extern struct vfsmount *selinuxfs_mount;
1707 extern struct dentry *selinux_null;
1708
1709 /* Derived from fs/exec.c:flush_old_files. */
1710 static inline void flush_unauthorized_files(struct files_struct * files)
1711 {
1712         struct avc_audit_data ad;
1713         struct file *file, *devnull = NULL;
1714         struct tty_struct *tty = current->signal->tty;
1715         struct fdtable *fdt;
1716         long j = -1;
1717
1718         if (tty) {
1719                 file_list_lock();
1720                 file = list_entry(tty->tty_files.next, typeof(*file), f_u.fu_list);
1721                 if (file) {
1722                         /* Revalidate access to controlling tty.
1723                            Use inode_has_perm on the tty inode directly rather
1724                            than using file_has_perm, as this particular open
1725                            file may belong to another process and we are only
1726                            interested in the inode-based check here. */
1727                         struct inode *inode = file->f_dentry->d_inode;
1728                         if (inode_has_perm(current, inode,
1729                                            FILE__READ | FILE__WRITE, NULL)) {
1730                                 /* Reset controlling tty. */
1731                                 current->signal->tty = NULL;
1732                                 current->signal->tty_old_pgrp = 0;
1733                         }
1734                 }
1735                 file_list_unlock();
1736         }
1737
1738         /* Revalidate access to inherited open files. */
1739
1740         AVC_AUDIT_DATA_INIT(&ad,FS);
1741
1742         spin_lock(&files->file_lock);
1743         for (;;) {
1744                 unsigned long set, i;
1745                 int fd;
1746
1747                 j++;
1748                 i = j * __NFDBITS;
1749                 fdt = files_fdtable(files);
1750                 if (i >= fdt->max_fds || i >= fdt->max_fdset)
1751                         break;
1752                 set = fdt->open_fds->fds_bits[j];
1753                 if (!set)
1754                         continue;
1755                 spin_unlock(&files->file_lock);
1756                 for ( ; set ; i++,set >>= 1) {
1757                         if (set & 1) {
1758                                 file = fget(i);
1759                                 if (!file)
1760                                         continue;
1761                                 if (file_has_perm(current,
1762                                                   file,
1763                                                   file_to_av(file))) {
1764                                         sys_close(i);
1765                                         fd = get_unused_fd();
1766                                         if (fd != i) {
1767                                                 if (fd >= 0)
1768                                                         put_unused_fd(fd);
1769                                                 fput(file);
1770                                                 continue;
1771                                         }
1772                                         if (devnull) {
1773                                                 get_file(devnull);
1774                                         } else {
1775                                                 devnull = dentry_open(dget(selinux_null), mntget(selinuxfs_mount), O_RDWR);
1776                                                 if (!devnull) {
1777                                                         put_unused_fd(fd);
1778                                                         fput(file);
1779                                                         continue;
1780                                                 }
1781                                         }
1782                                         fd_install(fd, devnull);
1783                                 }
1784                                 fput(file);
1785                         }
1786                 }
1787                 spin_lock(&files->file_lock);
1788
1789         }
1790         spin_unlock(&files->file_lock);
1791 }
1792
1793 static void selinux_bprm_apply_creds(struct linux_binprm *bprm, int unsafe)
1794 {
1795         struct task_security_struct *tsec;
1796         struct bprm_security_struct *bsec;
1797         u32 sid;
1798         int rc;
1799
1800         secondary_ops->bprm_apply_creds(bprm, unsafe);
1801
1802         tsec = current->security;
1803
1804         bsec = bprm->security;
1805         sid = bsec->sid;
1806
1807         tsec->osid = tsec->sid;
1808         bsec->unsafe = 0;
1809         if (tsec->sid != sid) {
1810                 /* Check for shared state.  If not ok, leave SID
1811                    unchanged and kill. */
1812                 if (unsafe & LSM_UNSAFE_SHARE) {
1813                         rc = avc_has_perm(tsec->sid, sid, SECCLASS_PROCESS,
1814                                         PROCESS__SHARE, NULL);
1815                         if (rc) {
1816                                 bsec->unsafe = 1;
1817                                 return;
1818                         }
1819                 }
1820
1821                 /* Check for ptracing, and update the task SID if ok.
1822                    Otherwise, leave SID unchanged and kill. */
1823                 if (unsafe & (LSM_UNSAFE_PTRACE | LSM_UNSAFE_PTRACE_CAP)) {
1824                         rc = avc_has_perm(tsec->ptrace_sid, sid,
1825                                           SECCLASS_PROCESS, PROCESS__PTRACE,
1826                                           NULL);
1827                         if (rc) {
1828                                 bsec->unsafe = 1;
1829                                 return;
1830                         }
1831                 }
1832                 tsec->sid = sid;
1833         }
1834 }
1835
1836 /*
1837  * called after apply_creds without the task lock held
1838  */
1839 static void selinux_bprm_post_apply_creds(struct linux_binprm *bprm)
1840 {
1841         struct task_security_struct *tsec;
1842         struct rlimit *rlim, *initrlim;
1843         struct itimerval itimer;
1844         struct bprm_security_struct *bsec;
1845         int rc, i;
1846
1847         tsec = current->security;
1848         bsec = bprm->security;
1849
1850         if (bsec->unsafe) {
1851                 force_sig_specific(SIGKILL, current);
1852                 return;
1853         }
1854         if (tsec->osid == tsec->sid)
1855                 return;
1856
1857         /* Close files for which the new task SID is not authorized. */
1858         flush_unauthorized_files(current->files);
1859
1860         /* Check whether the new SID can inherit signal state
1861            from the old SID.  If not, clear itimers to avoid
1862            subsequent signal generation and flush and unblock
1863            signals. This must occur _after_ the task SID has
1864           been updated so that any kill done after the flush
1865           will be checked against the new SID. */
1866         rc = avc_has_perm(tsec->osid, tsec->sid, SECCLASS_PROCESS,
1867                           PROCESS__SIGINH, NULL);
1868         if (rc) {
1869                 memset(&itimer, 0, sizeof itimer);
1870                 for (i = 0; i < 3; i++)
1871                         do_setitimer(i, &itimer, NULL);
1872                 flush_signals(current);
1873                 spin_lock_irq(&current->sighand->siglock);
1874                 flush_signal_handlers(current, 1);
1875                 sigemptyset(&current->blocked);
1876                 recalc_sigpending();
1877                 spin_unlock_irq(&current->sighand->siglock);
1878         }
1879
1880         /* Check whether the new SID can inherit resource limits
1881            from the old SID.  If not, reset all soft limits to
1882            the lower of the current task's hard limit and the init
1883            task's soft limit.  Note that the setting of hard limits
1884            (even to lower them) can be controlled by the setrlimit
1885            check. The inclusion of the init task's soft limit into
1886            the computation is to avoid resetting soft limits higher
1887            than the default soft limit for cases where the default
1888            is lower than the hard limit, e.g. RLIMIT_CORE or
1889            RLIMIT_STACK.*/
1890         rc = avc_has_perm(tsec->osid, tsec->sid, SECCLASS_PROCESS,
1891                           PROCESS__RLIMITINH, NULL);
1892         if (rc) {
1893                 for (i = 0; i < RLIM_NLIMITS; i++) {
1894                         rlim = current->signal->rlim + i;
1895                         initrlim = init_task.signal->rlim+i;
1896                         rlim->rlim_cur = min(rlim->rlim_max,initrlim->rlim_cur);
1897                 }
1898                 if (current->signal->rlim[RLIMIT_CPU].rlim_cur != RLIM_INFINITY) {
1899                         /*
1900                          * This will cause RLIMIT_CPU calculations
1901                          * to be refigured.
1902                          */
1903                         current->it_prof_expires = jiffies_to_cputime(1);
1904                 }
1905         }
1906
1907         /* Wake up the parent if it is waiting so that it can
1908            recheck wait permission to the new task SID. */
1909         wake_up_interruptible(&current->parent->signal->wait_chldexit);
1910 }
1911
1912 /* superblock security operations */
1913
1914 static int selinux_sb_alloc_security(struct super_block *sb)
1915 {
1916         return superblock_alloc_security(sb);
1917 }
1918
1919 static void selinux_sb_free_security(struct super_block *sb)
1920 {
1921         superblock_free_security(sb);
1922 }
1923
1924 static inline int match_prefix(char *prefix, int plen, char *option, int olen)
1925 {
1926         if (plen > olen)
1927                 return 0;
1928
1929         return !memcmp(prefix, option, plen);
1930 }
1931
1932 static inline int selinux_option(char *option, int len)
1933 {
1934         return (match_prefix("context=", sizeof("context=")-1, option, len) ||
1935                 match_prefix("fscontext=", sizeof("fscontext=")-1, option, len) ||
1936                 match_prefix("defcontext=", sizeof("defcontext=")-1, option, len) ||
1937                 match_prefix("rootcontext=", sizeof("rootcontext=")-1, option, len));
1938 }
1939
1940 static inline void take_option(char **to, char *from, int *first, int len)
1941 {
1942         if (!*first) {
1943                 **to = ',';
1944                 *to += 1;
1945         }
1946         else
1947                 *first = 0;
1948         memcpy(*to, from, len);
1949         *to += len;
1950 }
1951
1952 static int selinux_sb_copy_data(struct file_system_type *type, void *orig, void *copy)
1953 {
1954         int fnosec, fsec, rc = 0;
1955         char *in_save, *in_curr, *in_end;
1956         char *sec_curr, *nosec_save, *nosec;
1957
1958         in_curr = orig;
1959         sec_curr = copy;
1960
1961         /* Binary mount data: just copy */
1962         if (type->fs_flags & FS_BINARY_MOUNTDATA) {
1963                 copy_page(sec_curr, in_curr);
1964                 goto out;
1965         }
1966
1967         nosec = (char *)get_zeroed_page(GFP_KERNEL);
1968         if (!nosec) {
1969                 rc = -ENOMEM;
1970                 goto out;
1971         }
1972
1973         nosec_save = nosec;
1974         fnosec = fsec = 1;
1975         in_save = in_end = orig;
1976
1977         do {
1978                 if (*in_end == ',' || *in_end == '\0') {
1979                         int len = in_end - in_curr;
1980
1981                         if (selinux_option(in_curr, len))
1982                                 take_option(&sec_curr, in_curr, &fsec, len);
1983                         else
1984                                 take_option(&nosec, in_curr, &fnosec, len);
1985
1986                         in_curr = in_end + 1;
1987                 }
1988         } while (*in_end++);
1989
1990         strcpy(in_save, nosec_save);
1991         free_page((unsigned long)nosec_save);
1992 out:
1993         return rc;
1994 }
1995
1996 static int selinux_sb_kern_mount(struct super_block *sb, void *data)
1997 {
1998         struct avc_audit_data ad;
1999         int rc;
2000
2001         rc = superblock_doinit(sb, data);
2002         if (rc)
2003                 return rc;
2004
2005         AVC_AUDIT_DATA_INIT(&ad,FS);
2006         ad.u.fs.dentry = sb->s_root;
2007         return superblock_has_perm(current, sb, FILESYSTEM__MOUNT, &ad);
2008 }
2009
2010 static int selinux_sb_statfs(struct dentry *dentry)
2011 {
2012         struct avc_audit_data ad;
2013
2014         AVC_AUDIT_DATA_INIT(&ad,FS);
2015         ad.u.fs.dentry = dentry->d_sb->s_root;
2016         return superblock_has_perm(current, dentry->d_sb, FILESYSTEM__GETATTR, &ad);
2017 }
2018
2019 static int selinux_mount(char * dev_name,
2020                          struct nameidata *nd,
2021                          char * type,
2022                          unsigned long flags,
2023                          void * data)
2024 {
2025         int rc;
2026
2027         rc = secondary_ops->sb_mount(dev_name, nd, type, flags, data);
2028         if (rc)
2029                 return rc;
2030
2031         if (flags & MS_REMOUNT)
2032                 return superblock_has_perm(current, nd->mnt->mnt_sb,
2033                                            FILESYSTEM__REMOUNT, NULL);
2034         else
2035                 return dentry_has_perm(current, nd->mnt, nd->dentry,
2036                                        FILE__MOUNTON);
2037 }
2038
2039 static int selinux_umount(struct vfsmount *mnt, int flags)
2040 {
2041         int rc;
2042
2043         rc = secondary_ops->sb_umount(mnt, flags);
2044         if (rc)
2045                 return rc;
2046
2047         return superblock_has_perm(current,mnt->mnt_sb,
2048                                    FILESYSTEM__UNMOUNT,NULL);
2049 }
2050
2051 /* inode security operations */
2052
2053 static int selinux_inode_alloc_security(struct inode *inode)
2054 {
2055         return inode_alloc_security(inode);
2056 }
2057
2058 static void selinux_inode_free_security(struct inode *inode)
2059 {
2060         inode_free_security(inode);
2061 }
2062
2063 static int selinux_inode_init_security(struct inode *inode, struct inode *dir,
2064                                        char **name, void **value,
2065                                        size_t *len)
2066 {
2067         struct task_security_struct *tsec;
2068         struct inode_security_struct *dsec;
2069         struct superblock_security_struct *sbsec;
2070         u32 newsid, clen;
2071         int rc;
2072         char *namep = NULL, *context;
2073
2074         tsec = current->security;
2075         dsec = dir->i_security;
2076         sbsec = dir->i_sb->s_security;
2077
2078         if (tsec->create_sid && sbsec->behavior != SECURITY_FS_USE_MNTPOINT) {
2079                 newsid = tsec->create_sid;
2080         } else {
2081                 rc = security_transition_sid(tsec->sid, dsec->sid,
2082                                              inode_mode_to_security_class(inode->i_mode),
2083                                              &newsid);
2084                 if (rc) {
2085                         printk(KERN_WARNING "%s:  "
2086                                "security_transition_sid failed, rc=%d (dev=%s "
2087                                "ino=%ld)\n",
2088                                __FUNCTION__,
2089                                -rc, inode->i_sb->s_id, inode->i_ino);
2090                         return rc;
2091                 }
2092         }
2093
2094         inode_security_set_sid(inode, newsid);
2095
2096         if (!ss_initialized || sbsec->behavior == SECURITY_FS_USE_MNTPOINT)
2097                 return -EOPNOTSUPP;
2098
2099         if (name) {
2100                 namep = kstrdup(XATTR_SELINUX_SUFFIX, GFP_KERNEL);
2101                 if (!namep)
2102                         return -ENOMEM;
2103                 *name = namep;
2104         }
2105
2106         if (value && len) {
2107                 rc = security_sid_to_context(newsid, &context, &clen);
2108                 if (rc) {
2109                         kfree(namep);
2110                         return rc;
2111                 }
2112                 *value = context;
2113                 *len = clen;
2114         }
2115
2116         return 0;
2117 }
2118
2119 static int selinux_inode_create(struct inode *dir, struct dentry *dentry, int mask)
2120 {
2121         return may_create(dir, dentry, SECCLASS_FILE);
2122 }
2123
2124 static int selinux_inode_link(struct dentry *old_dentry, struct inode *dir, struct dentry *new_dentry)
2125 {
2126         int rc;
2127
2128         rc = secondary_ops->inode_link(old_dentry,dir,new_dentry);
2129         if (rc)
2130                 return rc;
2131         return may_link(dir, old_dentry, MAY_LINK);
2132 }
2133
2134 static int selinux_inode_unlink(struct inode *dir, struct dentry *dentry)
2135 {
2136         int rc;
2137
2138         rc = secondary_ops->inode_unlink(dir, dentry);
2139         if (rc)
2140                 return rc;
2141         return may_link(dir, dentry, MAY_UNLINK);
2142 }
2143
2144 static int selinux_inode_symlink(struct inode *dir, struct dentry *dentry, const char *name)
2145 {
2146         return may_create(dir, dentry, SECCLASS_LNK_FILE);
2147 }
2148
2149 static int selinux_inode_mkdir(struct inode *dir, struct dentry *dentry, int mask)
2150 {
2151         return may_create(dir, dentry, SECCLASS_DIR);
2152 }
2153
2154 static int selinux_inode_rmdir(struct inode *dir, struct dentry *dentry)
2155 {
2156         return may_link(dir, dentry, MAY_RMDIR);
2157 }
2158
2159 static int selinux_inode_mknod(struct inode *dir, struct dentry *dentry, int mode, dev_t dev)
2160 {
2161         int rc;
2162
2163         rc = secondary_ops->inode_mknod(dir, dentry, mode, dev);
2164         if (rc)
2165                 return rc;
2166
2167         return may_create(dir, dentry, inode_mode_to_security_class(mode));
2168 }
2169
2170 static int selinux_inode_rename(struct inode *old_inode, struct dentry *old_dentry,
2171                                 struct inode *new_inode, struct dentry *new_dentry)
2172 {
2173         return may_rename(old_inode, old_dentry, new_inode, new_dentry);
2174 }
2175
2176 static int selinux_inode_readlink(struct dentry *dentry)
2177 {
2178         return dentry_has_perm(current, NULL, dentry, FILE__READ);
2179 }
2180
2181 static int selinux_inode_follow_link(struct dentry *dentry, struct nameidata *nameidata)
2182 {
2183         int rc;
2184
2185         rc = secondary_ops->inode_follow_link(dentry,nameidata);
2186         if (rc)
2187                 return rc;
2188         return dentry_has_perm(current, NULL, dentry, FILE__READ);
2189 }
2190
2191 static int selinux_inode_permission(struct inode *inode, int mask,
2192                                     struct nameidata *nd)
2193 {
2194         int rc;
2195
2196         rc = secondary_ops->inode_permission(inode, mask, nd);
2197         if (rc)
2198                 return rc;
2199
2200         if (!mask) {
2201                 /* No permission to check.  Existence test. */
2202                 return 0;
2203         }
2204
2205         return inode_has_perm(current, inode,
2206                                file_mask_to_av(inode->i_mode, mask), NULL);
2207 }
2208
2209 static int selinux_inode_setattr(struct dentry *dentry, struct iattr *iattr)
2210 {
2211         int rc;
2212
2213         rc = secondary_ops->inode_setattr(dentry, iattr);
2214         if (rc)
2215                 return rc;
2216
2217         if (iattr->ia_valid & ATTR_FORCE)
2218                 return 0;
2219
2220         if (iattr->ia_valid & (ATTR_MODE | ATTR_UID | ATTR_GID |
2221                                ATTR_ATIME_SET | ATTR_MTIME_SET))
2222                 return dentry_has_perm(current, NULL, dentry, FILE__SETATTR);
2223
2224         return dentry_has_perm(current, NULL, dentry, FILE__WRITE);
2225 }
2226
2227 static int selinux_inode_getattr(struct vfsmount *mnt, struct dentry *dentry)
2228 {
2229         return dentry_has_perm(current, mnt, dentry, FILE__GETATTR);
2230 }
2231
2232 static int selinux_inode_setxattr(struct dentry *dentry, char *name, void *value, size_t size, int flags)
2233 {
2234         struct task_security_struct *tsec = current->security;
2235         struct inode *inode = dentry->d_inode;
2236         struct inode_security_struct *isec = inode->i_security;
2237         struct superblock_security_struct *sbsec;
2238         struct avc_audit_data ad;
2239         u32 newsid;
2240         int rc = 0;
2241
2242         if (strcmp(name, XATTR_NAME_SELINUX)) {
2243                 if (!strncmp(name, XATTR_SECURITY_PREFIX,
2244                              sizeof XATTR_SECURITY_PREFIX - 1) &&
2245                     !capable(CAP_SYS_ADMIN)) {
2246                         /* A different attribute in the security namespace.
2247                            Restrict to administrator. */
2248                         return -EPERM;
2249                 }
2250
2251                 /* Not an attribute we recognize, so just check the
2252                    ordinary setattr permission. */
2253                 return dentry_has_perm(current, NULL, dentry, FILE__SETATTR);
2254         }
2255
2256         sbsec = inode->i_sb->s_security;
2257         if (sbsec->behavior == SECURITY_FS_USE_MNTPOINT)
2258                 return -EOPNOTSUPP;
2259
2260         if ((current->fsuid != inode->i_uid) && !capable(CAP_FOWNER))
2261                 return -EPERM;
2262
2263         AVC_AUDIT_DATA_INIT(&ad,FS);
2264         ad.u.fs.dentry = dentry;
2265
2266         rc = avc_has_perm(tsec->sid, isec->sid, isec->sclass,
2267                           FILE__RELABELFROM, &ad);
2268         if (rc)
2269                 return rc;
2270
2271         rc = security_context_to_sid(value, size, &newsid);
2272         if (rc)
2273                 return rc;
2274
2275         rc = avc_has_perm(tsec->sid, newsid, isec->sclass,
2276                           FILE__RELABELTO, &ad);
2277         if (rc)
2278                 return rc;
2279
2280         rc = security_validate_transition(isec->sid, newsid, tsec->sid,
2281                                           isec->sclass);
2282         if (rc)
2283                 return rc;
2284
2285         return avc_has_perm(newsid,
2286                             sbsec->sid,
2287                             SECCLASS_FILESYSTEM,
2288                             FILESYSTEM__ASSOCIATE,
2289                             &ad);
2290 }
2291
2292 static void selinux_inode_post_setxattr(struct dentry *dentry, char *name,
2293                                         void *value, size_t size, int flags)
2294 {
2295         struct inode *inode = dentry->d_inode;
2296         struct inode_security_struct *isec = inode->i_security;
2297         u32 newsid;
2298         int rc;
2299
2300         if (strcmp(name, XATTR_NAME_SELINUX)) {
2301                 /* Not an attribute we recognize, so nothing to do. */
2302                 return;
2303         }
2304
2305         rc = security_context_to_sid(value, size, &newsid);
2306         if (rc) {
2307                 printk(KERN_WARNING "%s:  unable to obtain SID for context "
2308                        "%s, rc=%d\n", __FUNCTION__, (char*)value, -rc);
2309                 return;
2310         }
2311
2312         isec->sid = newsid;
2313         return;
2314 }
2315
2316 static int selinux_inode_getxattr (struct dentry *dentry, char *name)
2317 {
2318         return dentry_has_perm(current, NULL, dentry, FILE__GETATTR);
2319 }
2320
2321 static int selinux_inode_listxattr (struct dentry *dentry)
2322 {
2323         return dentry_has_perm(current, NULL, dentry, FILE__GETATTR);
2324 }
2325
2326 static int selinux_inode_removexattr (struct dentry *dentry, char *name)
2327 {
2328         if (strcmp(name, XATTR_NAME_SELINUX)) {
2329                 if (!strncmp(name, XATTR_SECURITY_PREFIX,
2330                              sizeof XATTR_SECURITY_PREFIX - 1) &&
2331                     !capable(CAP_SYS_ADMIN)) {
2332                         /* A different attribute in the security namespace.
2333                            Restrict to administrator. */
2334                         return -EPERM;
2335                 }
2336
2337                 /* Not an attribute we recognize, so just check the
2338                    ordinary setattr permission. Might want a separate
2339                    permission for removexattr. */
2340                 return dentry_has_perm(current, NULL, dentry, FILE__SETATTR);
2341         }
2342
2343         /* No one is allowed to remove a SELinux security label.
2344            You can change the label, but all data must be labeled. */
2345         return -EACCES;
2346 }
2347
2348 static const char *selinux_inode_xattr_getsuffix(void)
2349 {
2350       return XATTR_SELINUX_SUFFIX;
2351 }
2352
2353 /*
2354  * Copy the in-core inode security context value to the user.  If the
2355  * getxattr() prior to this succeeded, check to see if we need to
2356  * canonicalize the value to be finally returned to the user.
2357  *
2358  * Permission check is handled by selinux_inode_getxattr hook.
2359  */
2360 static int selinux_inode_getsecurity(const struct inode *inode, const char *name, void *buffer, size_t size, int err)
2361 {
2362         struct inode_security_struct *isec = inode->i_security;
2363
2364         if (strcmp(name, XATTR_SELINUX_SUFFIX))
2365                 return -EOPNOTSUPP;
2366
2367         return selinux_getsecurity(isec->sid, buffer, size);
2368 }
2369
2370 static int selinux_inode_setsecurity(struct inode *inode, const char *name,
2371                                      const void *value, size_t size, int flags)
2372 {
2373         struct inode_security_struct *isec = inode->i_security;
2374         u32 newsid;
2375         int rc;
2376
2377         if (strcmp(name, XATTR_SELINUX_SUFFIX))
2378                 return -EOPNOTSUPP;
2379
2380         if (!value || !size)
2381                 return -EACCES;
2382
2383         rc = security_context_to_sid((void*)value, size, &newsid);
2384         if (rc)
2385                 return rc;
2386
2387         isec->sid = newsid;
2388         return 0;
2389 }
2390
2391 static int selinux_inode_listsecurity(struct inode *inode, char *buffer, size_t buffer_size)
2392 {
2393         const int len = sizeof(XATTR_NAME_SELINUX);
2394         if (buffer && len <= buffer_size)
2395                 memcpy(buffer, XATTR_NAME_SELINUX, len);
2396         return len;
2397 }
2398
2399 /* file security operations */
2400
2401 static int selinux_file_permission(struct file *file, int mask)
2402 {
2403         struct inode *inode = file->f_dentry->d_inode;
2404
2405         if (!mask) {
2406                 /* No permission to check.  Existence test. */
2407                 return 0;
2408         }
2409
2410         /* file_mask_to_av won't add FILE__WRITE if MAY_APPEND is set */
2411         if ((file->f_flags & O_APPEND) && (mask & MAY_WRITE))
2412                 mask |= MAY_APPEND;
2413
2414         return file_has_perm(current, file,
2415                              file_mask_to_av(inode->i_mode, mask));
2416 }
2417
2418 static int selinux_file_alloc_security(struct file *file)
2419 {
2420         return file_alloc_security(file);
2421 }
2422
2423 static void selinux_file_free_security(struct file *file)
2424 {
2425         file_free_security(file);
2426 }
2427
2428 static int selinux_file_ioctl(struct file *file, unsigned int cmd,
2429                               unsigned long arg)
2430 {
2431         int error = 0;
2432
2433         switch (cmd) {
2434                 case FIONREAD:
2435                 /* fall through */
2436                 case FIBMAP:
2437                 /* fall through */
2438                 case FIGETBSZ:
2439                 /* fall through */
2440                 case EXT2_IOC_GETFLAGS:
2441                 /* fall through */
2442                 case EXT2_IOC_GETVERSION:
2443                         error = file_has_perm(current, file, FILE__GETATTR);
2444                         break;
2445
2446                 case EXT2_IOC_SETFLAGS:
2447                 /* fall through */
2448                 case EXT2_IOC_SETVERSION:
2449                         error = file_has_perm(current, file, FILE__SETATTR);
2450                         break;
2451
2452                 /* sys_ioctl() checks */
2453                 case FIONBIO:
2454                 /* fall through */
2455                 case FIOASYNC:
2456                         error = file_has_perm(current, file, 0);
2457                         break;
2458
2459                 case KDSKBENT:
2460                 case KDSKBSENT:
2461                         error = task_has_capability(current,CAP_SYS_TTY_CONFIG);
2462                         break;
2463
2464                 /* default case assumes that the command will go
2465                  * to the file's ioctl() function.
2466                  */
2467                 default:
2468                         error = file_has_perm(current, file, FILE__IOCTL);
2469
2470         }
2471         return error;
2472 }
2473
2474 static int file_map_prot_check(struct file *file, unsigned long prot, int shared)
2475 {
2476 #ifndef CONFIG_PPC32
2477         if ((prot & PROT_EXEC) && (!file || (!shared && (prot & PROT_WRITE)))) {
2478                 /*
2479                  * We are making executable an anonymous mapping or a
2480                  * private file mapping that will also be writable.
2481                  * This has an additional check.
2482                  */
2483                 int rc = task_has_perm(current, current, PROCESS__EXECMEM);
2484                 if (rc)
2485                         return rc;
2486         }
2487 #endif
2488
2489         if (file) {
2490                 /* read access is always possible with a mapping */
2491                 u32 av = FILE__READ;
2492
2493                 /* write access only matters if the mapping is shared */
2494                 if (shared && (prot & PROT_WRITE))
2495                         av |= FILE__WRITE;
2496
2497                 if (prot & PROT_EXEC)
2498                         av |= FILE__EXECUTE;
2499
2500                 return file_has_perm(current, file, av);
2501         }
2502         return 0;
2503 }
2504
2505 static int selinux_file_mmap(struct file *file, unsigned long reqprot,
2506                              unsigned long prot, unsigned long flags)
2507 {
2508         int rc;
2509
2510         rc = secondary_ops->file_mmap(file, reqprot, prot, flags);
2511         if (rc)
2512                 return rc;
2513
2514         if (selinux_checkreqprot)
2515                 prot = reqprot;
2516
2517         return file_map_prot_check(file, prot,
2518                                    (flags & MAP_TYPE) == MAP_SHARED);
2519 }
2520
2521 static int selinux_file_mprotect(struct vm_area_struct *vma,
2522                                  unsigned long reqprot,
2523                                  unsigned long prot)
2524 {
2525         int rc;
2526
2527         rc = secondary_ops->file_mprotect(vma, reqprot, prot);
2528         if (rc)
2529                 return rc;
2530
2531         if (selinux_checkreqprot)
2532                 prot = reqprot;
2533
2534 #ifndef CONFIG_PPC32
2535         if ((prot & PROT_EXEC) && !(vma->vm_flags & VM_EXEC)) {
2536                 rc = 0;
2537                 if (vma->vm_start >= vma->vm_mm->start_brk &&
2538                     vma->vm_end <= vma->vm_mm->brk) {
2539                         rc = task_has_perm(current, current,
2540                                            PROCESS__EXECHEAP);
2541                 } else if (!vma->vm_file &&
2542                            vma->vm_start <= vma->vm_mm->start_stack &&
2543                            vma->vm_end >= vma->vm_mm->start_stack) {
2544                         rc = task_has_perm(current, current, PROCESS__EXECSTACK);
2545                 } else if (vma->vm_file && vma->anon_vma) {
2546                         /*
2547                          * We are making executable a file mapping that has
2548                          * had some COW done. Since pages might have been
2549                          * written, check ability to execute the possibly
2550                          * modified content.  This typically should only
2551                          * occur for text relocations.
2552                          */
2553                         rc = file_has_perm(current, vma->vm_file,
2554                                            FILE__EXECMOD);
2555                 }
2556                 if (rc)
2557                         return rc;
2558         }
2559 #endif
2560
2561         return file_map_prot_check(vma->vm_file, prot, vma->vm_flags&VM_SHARED);
2562 }
2563
2564 static int selinux_file_lock(struct file *file, unsigned int cmd)
2565 {
2566         return file_has_perm(current, file, FILE__LOCK);
2567 }
2568
2569 static int selinux_file_fcntl(struct file *file, unsigned int cmd,
2570                               unsigned long arg)
2571 {
2572         int err = 0;
2573
2574         switch (cmd) {
2575                 case F_SETFL:
2576                         if (!file->f_dentry || !file->f_dentry->d_inode) {
2577                                 err = -EINVAL;
2578                                 break;
2579                         }
2580
2581                         if ((file->f_flags & O_APPEND) && !(arg & O_APPEND)) {
2582                                 err = file_has_perm(current, file,FILE__WRITE);
2583                                 break;
2584                         }
2585                         /* fall through */
2586                 case F_SETOWN:
2587                 case F_SETSIG:
2588                 case F_GETFL:
2589                 case F_GETOWN:
2590                 case F_GETSIG:
2591                         /* Just check FD__USE permission */
2592                         err = file_has_perm(current, file, 0);
2593                         break;
2594                 case F_GETLK:
2595                 case F_SETLK:
2596                 case F_SETLKW:
2597 #if BITS_PER_LONG == 32
2598                 case F_GETLK64:
2599                 case F_SETLK64:
2600                 case F_SETLKW64:
2601 #endif
2602                         if (!file->f_dentry || !file->f_dentry->d_inode) {
2603                                 err = -EINVAL;
2604                                 break;
2605                         }
2606                         err = file_has_perm(current, file, FILE__LOCK);
2607                         break;
2608         }
2609
2610         return err;
2611 }
2612
2613 static int selinux_file_set_fowner(struct file *file)
2614 {
2615         struct task_security_struct *tsec;
2616         struct file_security_struct *fsec;
2617
2618         tsec = current->security;
2619         fsec = file->f_security;
2620         fsec->fown_sid = tsec->sid;
2621
2622         return 0;
2623 }
2624
2625 static int selinux_file_send_sigiotask(struct task_struct *tsk,
2626                                        struct fown_struct *fown, int signum)
2627 {
2628         struct file *file;
2629         u32 perm;
2630         struct task_security_struct *tsec;
2631         struct file_security_struct *fsec;
2632
2633         /* struct fown_struct is never outside the context of a struct file */
2634         file = (struct file *)((long)fown - offsetof(struct file,f_owner));
2635
2636         tsec = tsk->security;
2637         fsec = file->f_security;
2638
2639         if (!signum)
2640                 perm = signal_to_av(SIGIO); /* as per send_sigio_to_task */
2641         else
2642                 perm = signal_to_av(signum);
2643
2644         return avc_has_perm(fsec->fown_sid, tsec->sid,
2645                             SECCLASS_PROCESS, perm, NULL);
2646 }
2647
2648 static int selinux_file_receive(struct file *file)
2649 {
2650         return file_has_perm(current, file, file_to_av(file));
2651 }
2652
2653 /* task security operations */
2654
2655 static int selinux_task_create(unsigned long clone_flags)
2656 {
2657         int rc;
2658
2659         rc = secondary_ops->task_create(clone_flags);
2660         if (rc)
2661                 return rc;
2662
2663         return task_has_perm(current, current, PROCESS__FORK);
2664 }
2665
2666 static int selinux_task_alloc_security(struct task_struct *tsk)
2667 {
2668         struct task_security_struct *tsec1, *tsec2;
2669         int rc;
2670
2671         tsec1 = current->security;
2672
2673         rc = task_alloc_security(tsk);
2674         if (rc)
2675                 return rc;
2676         tsec2 = tsk->security;
2677
2678         tsec2->osid = tsec1->osid;
2679         tsec2->sid = tsec1->sid;
2680
2681         /* Retain the exec, fs, key, and sock SIDs across fork */
2682         tsec2->exec_sid = tsec1->exec_sid;
2683         tsec2->create_sid = tsec1->create_sid;
2684         tsec2->keycreate_sid = tsec1->keycreate_sid;
2685         tsec2->sockcreate_sid = tsec1->sockcreate_sid;
2686
2687         /* Retain ptracer SID across fork, if any.
2688            This will be reset by the ptrace hook upon any
2689            subsequent ptrace_attach operations. */
2690         tsec2->ptrace_sid = tsec1->ptrace_sid;
2691
2692         return 0;
2693 }
2694
2695 static void selinux_task_free_security(struct task_struct *tsk)
2696 {
2697         task_free_security(tsk);
2698 }
2699
2700 static int selinux_task_setuid(uid_t id0, uid_t id1, uid_t id2, int flags)
2701 {
2702         /* Since setuid only affects the current process, and
2703            since the SELinux controls are not based on the Linux
2704            identity attributes, SELinux does not need to control
2705            this operation.  However, SELinux does control the use
2706            of the CAP_SETUID and CAP_SETGID capabilities using the
2707            capable hook. */
2708         return 0;
2709 }
2710
2711 static int selinux_task_post_setuid(uid_t id0, uid_t id1, uid_t id2, int flags)
2712 {
2713         return secondary_ops->task_post_setuid(id0,id1,id2,flags);
2714 }
2715
2716 static int selinux_task_setgid(gid_t id0, gid_t id1, gid_t id2, int flags)
2717 {
2718         /* See the comment for setuid above. */
2719         return 0;
2720 }
2721
2722 static int selinux_task_setpgid(struct task_struct *p, pid_t pgid)
2723 {
2724         return task_has_perm(current, p, PROCESS__SETPGID);
2725 }
2726
2727 static int selinux_task_getpgid(struct task_struct *p)
2728 {
2729         return task_has_perm(current, p, PROCESS__GETPGID);
2730 }
2731
2732 static int selinux_task_getsid(struct task_struct *p)
2733 {
2734         return task_has_perm(current, p, PROCESS__GETSESSION);
2735 }
2736
2737 static void selinux_task_getsecid(struct task_struct *p, u32 *secid)
2738 {
2739         selinux_get_task_sid(p, secid);
2740 }
2741
2742 static int selinux_task_setgroups(struct group_info *group_info)
2743 {
2744         /* See the comment for setuid above. */
2745         return 0;
2746 }
2747
2748 static int selinux_task_setnice(struct task_struct *p, int nice)
2749 {
2750         int rc;
2751
2752         rc = secondary_ops->task_setnice(p, nice);
2753         if (rc)
2754                 return rc;
2755
2756         return task_has_perm(current,p, PROCESS__SETSCHED);
2757 }
2758
2759 static int selinux_task_setioprio(struct task_struct *p, int ioprio)
2760 {
2761         return task_has_perm(current, p, PROCESS__SETSCHED);
2762 }
2763
2764 static int selinux_task_getioprio(struct task_struct *p)
2765 {
2766         return task_has_perm(current, p, PROCESS__GETSCHED);
2767 }
2768
2769 static int selinux_task_setrlimit(unsigned int resource, struct rlimit *new_rlim)
2770 {
2771         struct rlimit *old_rlim = current->signal->rlim + resource;
2772         int rc;
2773
2774         rc = secondary_ops->task_setrlimit(resource, new_rlim);
2775         if (rc)
2776                 return rc;
2777
2778         /* Control the ability to change the hard limit (whether
2779            lowering or raising it), so that the hard limit can
2780            later be used as a safe reset point for the soft limit
2781            upon context transitions. See selinux_bprm_apply_creds. */
2782         if (old_rlim->rlim_max != new_rlim->rlim_max)
2783                 return task_has_perm(current, current, PROCESS__SETRLIMIT);
2784
2785         return 0;
2786 }
2787
2788 static int selinux_task_setscheduler(struct task_struct *p, int policy, struct sched_param *lp)
2789 {
2790         return task_has_perm(current, p, PROCESS__SETSCHED);
2791 }
2792
2793 static int selinux_task_getscheduler(struct task_struct *p)
2794 {
2795         return task_has_perm(current, p, PROCESS__GETSCHED);
2796 }
2797
2798 static int selinux_task_movememory(struct task_struct *p)
2799 {
2800         return task_has_perm(current, p, PROCESS__SETSCHED);
2801 }
2802
2803 static int selinux_task_kill(struct task_struct *p, struct siginfo *info,
2804                                 int sig, u32 secid)
2805 {
2806         u32 perm;
2807         int rc;
2808         struct task_security_struct *tsec;
2809
2810         rc = secondary_ops->task_kill(p, info, sig, secid);
2811         if (rc)
2812                 return rc;
2813
2814         if (info != SEND_SIG_NOINFO && (is_si_special(info) || SI_FROMKERNEL(info)))
2815                 return 0;
2816
2817         if (!sig)
2818                 perm = PROCESS__SIGNULL; /* null signal; existence test */
2819         else
2820                 perm = signal_to_av(sig);
2821         tsec = p->security;
2822         if (secid)
2823                 rc = avc_has_perm(secid, tsec->sid, SECCLASS_PROCESS, perm, NULL);
2824         else
2825                 rc = task_has_perm(current, p, perm);
2826         return rc;
2827 }
2828
2829 static int selinux_task_prctl(int option,
2830                               unsigned long arg2,
2831                               unsigned long arg3,
2832                               unsigned long arg4,
2833                               unsigned long arg5)
2834 {
2835         /* The current prctl operations do not appear to require
2836            any SELinux controls since they merely observe or modify
2837            the state of the current process. */
2838         return 0;
2839 }
2840
2841 static int selinux_task_wait(struct task_struct *p)
2842 {
2843         u32 perm;
2844
2845         perm = signal_to_av(p->exit_signal);
2846
2847         return task_has_perm(p, current, perm);
2848 }
2849
2850 static void selinux_task_reparent_to_init(struct task_struct *p)
2851 {
2852         struct task_security_struct *tsec;
2853
2854         secondary_ops->task_reparent_to_init(p);
2855
2856         tsec = p->security;
2857         tsec->osid = tsec->sid;
2858         tsec->sid = SECINITSID_KERNEL;
2859         return;
2860 }
2861
2862 static void selinux_task_to_inode(struct task_struct *p,
2863                                   struct inode *inode)
2864 {
2865         struct task_security_struct *tsec = p->security;
2866         struct inode_security_struct *isec = inode->i_security;
2867
2868         isec->sid = tsec->sid;
2869         isec->initialized = 1;
2870         return;
2871 }
2872
2873 /* Returns error only if unable to parse addresses */
2874 static int selinux_parse_skb_ipv4(struct sk_buff *skb, struct avc_audit_data *ad)
2875 {
2876         int offset, ihlen, ret = -EINVAL;
2877         struct iphdr _iph, *ih;
2878
2879         offset = skb->nh.raw - skb->data;
2880         ih = skb_header_pointer(skb, offset, sizeof(_iph), &_iph);
2881         if (ih == NULL)
2882                 goto out;
2883
2884         ihlen = ih->ihl * 4;
2885         if (ihlen < sizeof(_iph))
2886                 goto out;
2887
2888         ad->u.net.v4info.saddr = ih->saddr;
2889         ad->u.net.v4info.daddr = ih->daddr;
2890         ret = 0;
2891
2892         switch (ih->protocol) {
2893         case IPPROTO_TCP: {
2894                 struct tcphdr _tcph, *th;
2895
2896                 if (ntohs(ih->frag_off) & IP_OFFSET)
2897                         break;
2898
2899                 offset += ihlen;
2900                 th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph);
2901                 if (th == NULL)
2902                         break;
2903
2904                 ad->u.net.sport = th->source;
2905                 ad->u.net.dport = th->dest;
2906                 break;
2907         }
2908
2909         case IPPROTO_UDP: {
2910                 struct udphdr _udph, *uh;
2911
2912                 if (ntohs(ih->frag_off) & IP_OFFSET)
2913                         break;
2914
2915                 offset += ihlen;
2916                 uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph);
2917                 if (uh == NULL)
2918                         break;
2919
2920                 ad->u.net.sport = uh->source;
2921                 ad->u.net.dport = uh->dest;
2922                 break;
2923         }
2924
2925         default:
2926                 break;
2927         }
2928 out:
2929         return ret;
2930 }
2931
2932 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
2933
2934 /* Returns error only if unable to parse addresses */
2935 static int selinux_parse_skb_ipv6(struct sk_buff *skb, struct avc_audit_data *ad)
2936 {
2937         u8 nexthdr;
2938         int ret = -EINVAL, offset;
2939         struct ipv6hdr _ipv6h, *ip6;
2940
2941         offset = skb->nh.raw - skb->data;
2942         ip6 = skb_header_pointer(skb, offset, sizeof(_ipv6h), &_ipv6h);
2943         if (ip6 == NULL)
2944                 goto out;
2945
2946         ipv6_addr_copy(&ad->u.net.v6info.saddr, &ip6->saddr);
2947         ipv6_addr_copy(&ad->u.net.v6info.daddr, &ip6->daddr);
2948         ret = 0;
2949
2950         nexthdr = ip6->nexthdr;
2951         offset += sizeof(_ipv6h);
2952         offset = ipv6_skip_exthdr(skb, offset, &nexthdr);
2953         if (offset < 0)
2954                 goto out;
2955
2956         switch (nexthdr) {
2957         case IPPROTO_TCP: {
2958                 struct tcphdr _tcph, *th;
2959
2960                 th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph);
2961                 if (th == NULL)
2962                         break;
2963
2964                 ad->u.net.sport = th->source;
2965                 ad->u.net.dport = th->dest;
2966                 break;
2967         }
2968
2969         case IPPROTO_UDP: {
2970                 struct udphdr _udph, *uh;
2971
2972                 uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph);
2973                 if (uh == NULL)
2974                         break;
2975
2976                 ad->u.net.sport = uh->source;
2977                 ad->u.net.dport = uh->dest;
2978                 break;
2979         }
2980
2981         /* includes fragments */
2982         default:
2983                 break;
2984         }
2985 out:
2986         return ret;
2987 }
2988
2989 #endif /* IPV6 */
2990
2991 static int selinux_parse_skb(struct sk_buff *skb, struct avc_audit_data *ad,
2992                              char **addrp, int *len, int src)
2993 {
2994         int ret = 0;
2995
2996         switch (ad->u.net.family) {
2997         case PF_INET:
2998                 ret = selinux_parse_skb_ipv4(skb, ad);
2999                 if (ret || !addrp)
3000                         break;
3001                 *len = 4;
3002                 *addrp = (char *)(src ? &ad->u.net.v4info.saddr :
3003                                         &ad->u.net.v4info.daddr);
3004                 break;
3005
3006 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
3007         case PF_INET6:
3008                 ret = selinux_parse_skb_ipv6(skb, ad);
3009                 if (ret || !addrp)
3010                         break;
3011                 *len = 16;
3012                 *addrp = (char *)(src ? &ad->u.net.v6info.saddr :
3013                                         &ad->u.net.v6info.daddr);
3014                 break;
3015 #endif  /* IPV6 */
3016         default:
3017                 break;
3018         }
3019
3020         return ret;
3021 }
3022
3023 /* socket security operations */
3024 static int socket_has_perm(struct task_struct *task, struct socket *sock,
3025                            u32 perms)
3026 {
3027         struct inode_security_struct *isec;
3028         struct task_security_struct *tsec;
3029         struct avc_audit_data ad;
3030         int err = 0;
3031
3032         tsec = task->security;
3033         isec = SOCK_INODE(sock)->i_security;
3034
3035         if (isec->sid == SECINITSID_KERNEL)
3036                 goto out;
3037
3038         AVC_AUDIT_DATA_INIT(&ad,NET);
3039         ad.u.net.sk = sock->sk;
3040         err = avc_has_perm(tsec->sid, isec->sid, isec->sclass, perms, &ad);
3041
3042 out:
3043         return err;
3044 }
3045
3046 static int selinux_socket_create(int family, int type,
3047                                  int protocol, int kern)
3048 {
3049         int err = 0;
3050         struct task_security_struct *tsec;
3051         u32 newsid;
3052
3053         if (kern)
3054                 goto out;
3055
3056         tsec = current->security;
3057         newsid = tsec->sockcreate_sid ? : tsec->sid;
3058         err = avc_has_perm(tsec->sid, newsid,
3059                            socket_type_to_security_class(family, type,
3060                            protocol), SOCKET__CREATE, NULL);
3061
3062 out:
3063         return err;
3064 }
3065
3066 static void selinux_socket_post_create(struct socket *sock, int family,
3067                                        int type, int protocol, int kern)
3068 {
3069         struct inode_security_struct *isec;
3070         struct task_security_struct *tsec;
3071         u32 newsid;
3072
3073         isec = SOCK_INODE(sock)->i_security;
3074
3075         tsec = current->security;
3076         newsid = tsec->sockcreate_sid ? : tsec->sid;
3077         isec->sclass = socket_type_to_security_class(family, type, protocol);
3078         isec->sid = kern ? SECINITSID_KERNEL : newsid;
3079         isec->initialized = 1;
3080
3081         return;
3082 }
3083
3084 /* Range of port numbers used to automatically bind.
3085    Need to determine whether we should perform a name_bind
3086    permission check between the socket and the port number. */
3087 #define ip_local_port_range_0 sysctl_local_port_range[0]
3088 #define ip_local_port_range_1 sysctl_local_port_range[1]
3089
3090 static int selinux_socket_bind(struct socket *sock, struct sockaddr *address, int addrlen)
3091 {
3092         u16 family;
3093         int err;
3094
3095         err = socket_has_perm(current, sock, SOCKET__BIND);
3096         if (err)
3097                 goto out;
3098
3099         /*
3100          * If PF_INET or PF_INET6, check name_bind permission for the port.
3101          * Multiple address binding for SCTP is not supported yet: we just
3102          * check the first address now.
3103          */
3104         family = sock->sk->sk_family;
3105         if (family == PF_INET || family == PF_INET6) {
3106                 char *addrp;
3107                 struct inode_security_struct *isec;
3108                 struct task_security_struct *tsec;
3109                 struct avc_audit_data ad;
3110                 struct sockaddr_in *addr4 = NULL;
3111                 struct sockaddr_in6 *addr6 = NULL;
3112                 unsigned short snum;
3113                 struct sock *sk = sock->sk;
3114                 u32 sid, node_perm, addrlen;
3115
3116                 tsec = current->security;
3117                 isec = SOCK_INODE(sock)->i_security;
3118
3119                 if (family == PF_INET) {
3120                         addr4 = (struct sockaddr_in *)address;
3121                         snum = ntohs(addr4->sin_port);
3122                         addrlen = sizeof(addr4->sin_addr.s_addr);
3123                         addrp = (char *)&addr4->sin_addr.s_addr;
3124                 } else {
3125                         addr6 = (struct sockaddr_in6 *)address;
3126                         snum = ntohs(addr6->sin6_port);
3127                         addrlen = sizeof(addr6->sin6_addr.s6_addr);
3128                         addrp = (char *)&addr6->sin6_addr.s6_addr;
3129                 }
3130
3131                 if (snum&&(snum < max(PROT_SOCK,ip_local_port_range_0) ||
3132                            snum > ip_local_port_range_1)) {
3133                         err = security_port_sid(sk->sk_family, sk->sk_type,
3134                                                 sk->sk_protocol, snum, &sid);
3135                         if (err)
3136                                 goto out;
3137                         AVC_AUDIT_DATA_INIT(&ad,NET);
3138                         ad.u.net.sport = htons(snum);
3139                         ad.u.net.family = family;
3140                         err = avc_has_perm(isec->sid, sid,
3141                                            isec->sclass,
3142                                            SOCKET__NAME_BIND, &ad);
3143                         if (err)
3144                                 goto out;
3145                 }
3146
3147                 switch(isec->sclass) {
3148                 case SECCLASS_TCP_SOCKET:
3149                         node_perm = TCP_SOCKET__NODE_BIND;
3150                         break;
3151
3152                 case SECCLASS_UDP_SOCKET:
3153                         node_perm = UDP_SOCKET__NODE_BIND;
3154                         break;
3155
3156                 default:
3157                         node_perm = RAWIP_SOCKET__NODE_BIND;
3158                         break;
3159                 }
3160
3161                 err = security_node_sid(family, addrp, addrlen, &sid);
3162                 if (err)
3163                         goto out;
3164
3165                 AVC_AUDIT_DATA_INIT(&ad,NET);
3166                 ad.u.net.sport = htons(snum);
3167                 ad.u.net.family = family;
3168
3169                 if (family == PF_INET)
3170                         ad.u.net.v4info.saddr = addr4->sin_addr.s_addr;
3171                 else
3172                         ipv6_addr_copy(&ad.u.net.v6info.saddr, &addr6->sin6_addr);
3173
3174                 err = avc_has_perm(isec->sid, sid,
3175                                    isec->sclass, node_perm, &ad);
3176                 if (err)
3177                         goto out;
3178         }
3179 out:
3180         return err;
3181 }
3182
3183 static int selinux_socket_connect(struct socket *sock, struct sockaddr *address, int addrlen)
3184 {
3185         struct inode_security_struct *isec;
3186         int err;
3187
3188         err = socket_has_perm(current, sock, SOCKET__CONNECT);
3189         if (err)
3190                 return err;
3191
3192         /*
3193          * If a TCP socket, check name_connect permission for the port.
3194          */
3195         isec = SOCK_INODE(sock)->i_security;
3196         if (isec->sclass == SECCLASS_TCP_SOCKET) {
3197                 struct sock *sk = sock->sk;
3198                 struct avc_audit_data ad;
3199                 struct sockaddr_in *addr4 = NULL;
3200                 struct sockaddr_in6 *addr6 = NULL;
3201                 unsigned short snum;
3202                 u32 sid;
3203
3204                 if (sk->sk_family == PF_INET) {
3205                         addr4 = (struct sockaddr_in *)address;
3206                         if (addrlen < sizeof(struct sockaddr_in))
3207                                 return -EINVAL;
3208                         snum = ntohs(addr4->sin_port);
3209                 } else {
3210                         addr6 = (struct sockaddr_in6 *)address;
3211                         if (addrlen < SIN6_LEN_RFC2133)
3212                                 return -EINVAL;
3213                         snum = ntohs(addr6->sin6_port);
3214                 }
3215
3216                 err = security_port_sid(sk->sk_family, sk->sk_type,
3217                                         sk->sk_protocol, snum, &sid);
3218                 if (err)
3219                         goto out;
3220
3221                 AVC_AUDIT_DATA_INIT(&ad,NET);
3222                 ad.u.net.dport = htons(snum);
3223                 ad.u.net.family = sk->sk_family;
3224                 err = avc_has_perm(isec->sid, sid, isec->sclass,
3225                                    TCP_SOCKET__NAME_CONNECT, &ad);
3226                 if (err)
3227                         goto out;
3228         }
3229
3230 out:
3231         return err;
3232 }
3233
3234 static int selinux_socket_listen(struct socket *sock, int backlog)
3235 {
3236         return socket_has_perm(current, sock, SOCKET__LISTEN);
3237 }
3238
3239 static int selinux_socket_accept(struct socket *sock, struct socket *newsock)
3240 {
3241         int err;
3242         struct inode_security_struct *isec;
3243         struct inode_security_struct *newisec;
3244
3245         err = socket_has_perm(current, sock, SOCKET__ACCEPT);
3246         if (err)
3247                 return err;
3248
3249         newisec = SOCK_INODE(newsock)->i_security;
3250
3251         isec = SOCK_INODE(sock)->i_security;
3252         newisec->sclass = isec->sclass;
3253         newisec->sid = isec->sid;
3254         newisec->initialized = 1;
3255
3256         return 0;
3257 }
3258
3259 static int selinux_socket_sendmsg(struct socket *sock, struct msghdr *msg,
3260                                   int size)
3261 {
3262         return socket_has_perm(current, sock, SOCKET__WRITE);
3263 }
3264
3265 static int selinux_socket_recvmsg(struct socket *sock, struct msghdr *msg,
3266                                   int size, int flags)
3267 {
3268         return socket_has_perm(current, sock, SOCKET__READ);
3269 }
3270
3271 static int selinux_socket_getsockname(struct socket *sock)
3272 {
3273         return socket_has_perm(current, sock, SOCKET__GETATTR);
3274 }
3275
3276 static int selinux_socket_getpeername(struct socket *sock)
3277 {
3278         return socket_has_perm(current, sock, SOCKET__GETATTR);
3279 }
3280
3281 static int selinux_socket_setsockopt(struct socket *sock,int level,int optname)
3282 {
3283         return socket_has_perm(current, sock, SOCKET__SETOPT);
3284 }
3285
3286 static int selinux_socket_getsockopt(struct socket *sock, int level,
3287                                      int optname)
3288 {
3289         return socket_has_perm(current, sock, SOCKET__GETOPT);
3290 }
3291
3292 static int selinux_socket_shutdown(struct socket *sock, int how)
3293 {
3294         return socket_has_perm(current, sock, SOCKET__SHUTDOWN);
3295 }
3296
3297 static int selinux_socket_unix_stream_connect(struct socket *sock,
3298                                               struct socket *other,
3299                                               struct sock *newsk)
3300 {
3301         struct sk_security_struct *ssec;
3302         struct inode_security_struct *isec;
3303         struct inode_security_struct *other_isec;
3304         struct avc_audit_data ad;
3305         int err;
3306
3307         err = secondary_ops->unix_stream_connect(sock, other, newsk);
3308         if (err)
3309                 return err;
3310
3311         isec = SOCK_INODE(sock)->i_security;
3312         other_isec = SOCK_INODE(other)->i_security;
3313
3314         AVC_AUDIT_DATA_INIT(&ad,NET);
3315         ad.u.net.sk = other->sk;
3316
3317         err = avc_has_perm(isec->sid, other_isec->sid,
3318                            isec->sclass,
3319                            UNIX_STREAM_SOCKET__CONNECTTO, &ad);
3320         if (err)
3321                 return err;
3322
3323         /* connecting socket */
3324         ssec = sock->sk->sk_security;
3325         ssec->peer_sid = other_isec->sid;
3326
3327         /* server child socket */
3328         ssec = newsk->sk_security;
3329         ssec->peer_sid = isec->sid;
3330
3331         return 0;
3332 }
3333
3334 static int selinux_socket_unix_may_send(struct socket *sock,
3335                                         struct socket *other)
3336 {
3337         struct inode_security_struct *isec;
3338         struct inode_security_struct *other_isec;
3339         struct avc_audit_data ad;
3340         int err;
3341
3342         isec = SOCK_INODE(sock)->i_security;
3343         other_isec = SOCK_INODE(other)->i_security;
3344
3345         AVC_AUDIT_DATA_INIT(&ad,NET);
3346         ad.u.net.sk = other->sk;
3347
3348         err = avc_has_perm(isec->sid, other_isec->sid,
3349                            isec->sclass, SOCKET__SENDTO, &ad);
3350         if (err)
3351                 return err;
3352
3353         return 0;
3354 }
3355
3356 static int selinux_sock_rcv_skb_compat(struct sock *sk, struct sk_buff *skb,
3357                 struct avc_audit_data *ad, u32 sock_sid, u16 sock_class,
3358                 u16 family, char *addrp, int len)
3359 {
3360         int err = 0;
3361         u32 netif_perm, node_perm, node_sid, if_sid, recv_perm = 0;
3362
3363         if (!skb->dev)
3364                 goto out;
3365
3366         err = sel_netif_sids(skb->dev, &if_sid, NULL);
3367         if (err)
3368                 goto out;
3369
3370         switch (sock_class) {
3371         case SECCLASS_UDP_SOCKET:
3372                 netif_perm = NETIF__UDP_RECV;
3373                 node_perm = NODE__UDP_RECV;
3374                 recv_perm = UDP_SOCKET__RECV_MSG;
3375                 break;
3376
3377         case SECCLASS_TCP_SOCKET:
3378                 netif_perm = NETIF__TCP_RECV;
3379                 node_perm = NODE__TCP_RECV;
3380                 recv_perm = TCP_SOCKET__RECV_MSG;
3381                 break;
3382
3383         default:
3384                 netif_perm = NETIF__RAWIP_RECV;
3385                 node_perm = NODE__RAWIP_RECV;
3386                 break;
3387         }
3388
3389         err = avc_has_perm(sock_sid, if_sid, SECCLASS_NETIF, netif_perm, ad);
3390         if (err)
3391                 goto out;
3392
3393         err = security_node_sid(family, addrp, len, &node_sid);
3394         if (err)
3395                 goto out;
3396
3397         err = avc_has_perm(sock_sid, node_sid, SECCLASS_NODE, node_perm, ad);
3398         if (err)
3399                 goto out;
3400
3401         if (recv_perm) {
3402                 u32 port_sid;
3403
3404                 err = security_port_sid(sk->sk_family, sk->sk_type,
3405                                         sk->sk_protocol, ntohs(ad->u.net.sport),
3406                                         &port_sid);
3407                 if (err)
3408                         goto out;
3409
3410                 err = avc_has_perm(sock_sid, port_sid,
3411                                    sock_class, recv_perm, ad);
3412         }
3413
3414 out:
3415         return err;
3416 }
3417
3418 static int selinux_socket_sock_rcv_skb(struct sock *sk, struct sk_buff *skb)
3419 {
3420         u16 family;
3421         u16 sock_class = 0;
3422         char *addrp;
3423         int len, err = 0;
3424         u32 sock_sid = 0;
3425         struct socket *sock;
3426         struct avc_audit_data ad;
3427
3428         family = sk->sk_family;
3429         if (family != PF_INET && family != PF_INET6)
3430                 goto out;
3431
3432         /* Handle mapped IPv4 packets arriving via IPv6 sockets */
3433         if (family == PF_INET6 && skb->protocol == ntohs(ETH_P_IP))
3434                 family = PF_INET;
3435
3436         read_lock_bh(&sk->sk_callback_lock);
3437         sock = sk->sk_socket;
3438         if (sock) {
3439                 struct inode *inode;
3440                 inode = SOCK_INODE(sock);
3441                 if (inode) {
3442                         struct inode_security_struct *isec;
3443                         isec = inode->i_security;
3444                         sock_sid = isec->sid;
3445                         sock_class = isec->sclass;
3446                 }
3447         }
3448         read_unlock_bh(&sk->sk_callback_lock);
3449         if (!sock_sid)
3450                 goto out;
3451
3452         AVC_AUDIT_DATA_INIT(&ad, NET);
3453         ad.u.net.netif = skb->dev ? skb->dev->name : "[unknown]";
3454         ad.u.net.family = family;
3455
3456         err = selinux_parse_skb(skb, &ad, &addrp, &len, 1);
3457         if (err)
3458                 goto out;
3459
3460         if (selinux_compat_net)
3461                 err = selinux_sock_rcv_skb_compat(sk, skb, &ad, sock_sid,
3462                                                   sock_class, family,
3463                                                   addrp, len);
3464         else
3465                 err = avc_has_perm(sock_sid, skb->secmark, SECCLASS_PACKET,
3466                                    PACKET__RECV, &ad);
3467         if (err)
3468                 goto out;
3469
3470         err = selinux_xfrm_sock_rcv_skb(sock_sid, skb);
3471 out:
3472         return err;
3473 }
3474
3475 static int selinux_socket_getpeersec_stream(struct socket *sock, char __user *optval,
3476                                             int __user *optlen, unsigned len)
3477 {
3478         int err = 0;
3479         char *scontext;
3480         u32 scontext_len;
3481         struct sk_security_struct *ssec;
3482         struct inode_security_struct *isec;
3483         u32 peer_sid = 0;
3484
3485         isec = SOCK_INODE(sock)->i_security;
3486
3487         /* if UNIX_STREAM check peer_sid, if TCP check dst for labelled sa */
3488         if (isec->sclass == SECCLASS_UNIX_STREAM_SOCKET) {
3489                 ssec = sock->sk->sk_security;
3490                 peer_sid = ssec->peer_sid;
3491         }
3492         else if (isec->sclass == SECCLASS_TCP_SOCKET) {
3493                 peer_sid = selinux_socket_getpeer_stream(sock->sk);
3494
3495                 if (peer_sid == SECSID_NULL) {
3496                         err = -ENOPROTOOPT;
3497                         goto out;
3498                 }
3499         }
3500         else {
3501                 err = -ENOPROTOOPT;
3502                 goto out;
3503         }
3504
3505         err = security_sid_to_context(peer_sid, &scontext, &scontext_len);
3506
3507         if (err)
3508                 goto out;
3509
3510         if (scontext_len > len) {
3511                 err = -ERANGE;
3512                 goto out_len;
3513         }
3514
3515         if (copy_to_user(optval, scontext, scontext_len))
3516                 err = -EFAULT;
3517
3518 out_len:
3519         if (put_user(scontext_len, optlen))
3520                 err = -EFAULT;
3521
3522         kfree(scontext);
3523 out:
3524         return err;
3525 }
3526
3527 static int selinux_socket_getpeersec_dgram(struct socket *sock, struct sk_buff *skb, u32 *secid)
3528 {
3529         u32 peer_secid = SECSID_NULL;
3530         int err = 0;
3531
3532         if (sock && (sock->sk->sk_family == PF_UNIX))
3533                 selinux_get_inode_sid(SOCK_INODE(sock), &peer_secid);
3534         else if (skb)
3535                 peer_secid = selinux_socket_getpeer_dgram(skb);
3536
3537         if (peer_secid == SECSID_NULL)
3538                 err = -EINVAL;
3539         *secid = peer_secid;
3540
3541         return err;
3542 }
3543
3544 static int selinux_sk_alloc_security(struct sock *sk, int family, gfp_t priority)
3545 {
3546         return sk_alloc_security(sk, family, priority);
3547 }
3548
3549 static void selinux_sk_free_security(struct sock *sk)
3550 {
3551         sk_free_security(sk);
3552 }
3553
3554 static unsigned int selinux_sk_getsid_security(struct sock *sk, struct flowi *fl, u8 dir)
3555 {
3556         struct inode_security_struct *isec;
3557         u32 sock_sid = SECINITSID_ANY_SOCKET;
3558
3559         if (!sk)
3560                 return selinux_no_sk_sid(fl);
3561
3562         read_lock_bh(&sk->sk_callback_lock);
3563         isec = get_sock_isec(sk);
3564
3565         if (isec)
3566                 sock_sid = isec->sid;
3567
3568         read_unlock_bh(&sk->sk_callback_lock);
3569         return sock_sid;
3570 }
3571
3572 static int selinux_nlmsg_perm(struct sock *sk, struct sk_buff *skb)
3573 {
3574         int err = 0;
3575         u32 perm;
3576         struct nlmsghdr *nlh;
3577         struct socket *sock = sk->sk_socket;
3578         struct inode_security_struct *isec = SOCK_INODE(sock)->i_security;
3579
3580         if (skb->len < NLMSG_SPACE(0)) {
3581                 err = -EINVAL;
3582                 goto out;
3583         }
3584         nlh = (struct nlmsghdr *)skb->data;
3585
3586         err = selinux_nlmsg_lookup(isec->sclass, nlh->nlmsg_type, &perm);
3587         if (err) {
3588                 if (err == -EINVAL) {
3589                         audit_log(current->audit_context, GFP_KERNEL, AUDIT_SELINUX_ERR,
3590                                   "SELinux:  unrecognized netlink message"
3591                                   " type=%hu for sclass=%hu\n",
3592                                   nlh->nlmsg_type, isec->sclass);
3593                         if (!selinux_enforcing)
3594                                 err = 0;
3595                 }
3596
3597                 /* Ignore */
3598                 if (err == -ENOENT)
3599                         err = 0;
3600                 goto out;
3601         }
3602
3603         err = socket_has_perm(current, sock, perm);
3604 out:
3605         return err;
3606 }
3607
3608 #ifdef CONFIG_NETFILTER
3609
3610 static int selinux_ip_postroute_last_compat(struct sock *sk, struct net_device *dev,
3611                                             struct inode_security_struct *isec,
3612                                             struct avc_audit_data *ad,
3613                                             u16 family, char *addrp, int len)
3614 {
3615         int err;
3616         u32 netif_perm, node_perm, node_sid, if_sid, send_perm = 0;
3617
3618         err = sel_netif_sids(dev, &if_sid, NULL);
3619         if (err)
3620                 goto out;
3621
3622         switch (isec->sclass) {
3623         case SECCLASS_UDP_SOCKET:
3624                 netif_perm = NETIF__UDP_SEND;
3625                 node_perm = NODE__UDP_SEND;
3626                 send_perm = UDP_SOCKET__SEND_MSG;
3627                 break;
3628
3629         case SECCLASS_TCP_SOCKET:
3630                 netif_perm = NETIF__TCP_SEND;
3631                 node_perm = NODE__TCP_SEND;
3632                 send_perm = TCP_SOCKET__SEND_MSG;
3633                 break;
3634
3635         default:
3636                 netif_perm = NETIF__RAWIP_SEND;
3637                 node_perm = NODE__RAWIP_SEND;
3638                 break;
3639         }
3640
3641         err = avc_has_perm(isec->sid, if_sid, SECCLASS_NETIF, netif_perm, ad);
3642         if (err)
3643                 goto out;
3644
3645         err = security_node_sid(family, addrp, len, &node_sid);
3646         if (err)
3647                 goto out;
3648
3649         err = avc_has_perm(isec->sid, node_sid, SECCLASS_NODE, node_perm, ad);
3650         if (err)
3651                 goto out;
3652
3653         if (send_perm) {
3654                 u32 port_sid;
3655
3656                 err = security_port_sid(sk->sk_family,
3657                                         sk->sk_type,
3658                                         sk->sk_protocol,
3659                                         ntohs(ad->u.net.dport),
3660                                         &port_sid);
3661                 if (err)
3662                         goto out;
3663
3664                 err = avc_has_perm(isec->sid, port_sid, isec->sclass,
3665                                    send_perm, ad);
3666         }
3667 out:
3668         return err;
3669 }
3670
3671 static unsigned int selinux_ip_postroute_last(unsigned int hooknum,
3672                                               struct sk_buff **pskb,
3673                                               const struct net_device *in,
3674                                               const struct net_device *out,
3675                                               int (*okfn)(struct sk_buff *),
3676                                               u16 family)
3677 {
3678         char *addrp;
3679         int len, err = 0;
3680         struct sock *sk;
3681         struct socket *sock;
3682         struct inode *inode;
3683         struct sk_buff *skb = *pskb;
3684         struct inode_security_struct *isec;
3685         struct avc_audit_data ad;
3686         struct net_device *dev = (struct net_device *)out;
3687
3688         sk = skb->sk;
3689         if (!sk)
3690                 goto out;
3691
3692         sock = sk->sk_socket;
3693         if (!sock)
3694                 goto out;
3695
3696         inode = SOCK_INODE(sock);
3697         if (!inode)
3698                 goto out;
3699
3700         isec = inode->i_security;
3701
3702         AVC_AUDIT_DATA_INIT(&ad, NET);
3703         ad.u.net.netif = dev->name;
3704         ad.u.net.family = family;
3705
3706         err = selinux_parse_skb(skb, &ad, &addrp, &len, 0);
3707         if (err)
3708                 goto out;
3709
3710         if (selinux_compat_net)
3711                 err = selinux_ip_postroute_last_compat(sk, dev, isec, &ad,
3712                                                        family, addrp, len);
3713         else
3714                 err = avc_has_perm(isec->sid, skb->secmark, SECCLASS_PACKET,
3715                                    PACKET__SEND, &ad);
3716
3717         if (err)
3718                 goto out;
3719
3720         err = selinux_xfrm_postroute_last(isec->sid, skb);
3721 out:
3722         return err ? NF_DROP : NF_ACCEPT;
3723 }
3724
3725 static unsigned int selinux_ipv4_postroute_last(unsigned int hooknum,
3726                                                 struct sk_buff **pskb,
3727                                                 const struct net_device *in,
3728                                                 const struct net_device *out,
3729                                                 int (*okfn)(struct sk_buff *))
3730 {
3731         return selinux_ip_postroute_last(hooknum, pskb, in, out, okfn, PF_INET);
3732 }
3733
3734 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
3735
3736 static unsigned int selinux_ipv6_postroute_last(unsigned int hooknum,
3737                                                 struct sk_buff **pskb,
3738                                                 const struct net_device *in,
3739                                                 const struct net_device *out,
3740                                                 int (*okfn)(struct sk_buff *))
3741 {
3742         return selinux_ip_postroute_last(hooknum, pskb, in, out, okfn, PF_INET6);
3743 }
3744
3745 #endif  /* IPV6 */
3746
3747 #endif  /* CONFIG_NETFILTER */
3748
3749 static int selinux_netlink_send(struct sock *sk, struct sk_buff *skb)
3750 {
3751         int err;
3752
3753         err = secondary_ops->netlink_send(sk, skb);
3754         if (err)
3755                 return err;
3756
3757         if (policydb_loaded_version >= POLICYDB_VERSION_NLCLASS)
3758                 err = selinux_nlmsg_perm(sk, skb);
3759
3760         return err;
3761 }
3762
3763 static int selinux_netlink_recv(struct sk_buff *skb, int capability)
3764 {
3765         int err;
3766         struct avc_audit_data ad;
3767
3768         err = secondary_ops->netlink_recv(skb, capability);
3769         if (err)
3770                 return err;
3771
3772         AVC_AUDIT_DATA_INIT(&ad, CAP);
3773         ad.u.cap = capability;
3774
3775         return avc_has_perm(NETLINK_CB(skb).sid, NETLINK_CB(skb).sid,
3776                             SECCLASS_CAPABILITY, CAP_TO_MASK(capability), &ad);
3777 }
3778
3779 static int ipc_alloc_security(struct task_struct *task,
3780                               struct kern_ipc_perm *perm,
3781                               u16 sclass)
3782 {
3783         struct task_security_struct *tsec = task->security;
3784         struct ipc_security_struct *isec;
3785
3786         isec = kzalloc(sizeof(struct ipc_security_struct), GFP_KERNEL);
3787         if (!isec)
3788                 return -ENOMEM;
3789
3790         isec->sclass = sclass;
3791         isec->ipc_perm = perm;
3792         isec->sid = tsec->sid;
3793         perm->security = isec;
3794
3795         return 0;
3796 }
3797
3798 static void ipc_free_security(struct kern_ipc_perm *perm)
3799 {
3800         struct ipc_security_struct *isec = perm->security;
3801         perm->security = NULL;
3802         kfree(isec);
3803 }
3804
3805 static int msg_msg_alloc_security(struct msg_msg *msg)
3806 {
3807         struct msg_security_struct *msec;
3808
3809         msec = kzalloc(sizeof(struct msg_security_struct), GFP_KERNEL);
3810         if (!msec)
3811                 return -ENOMEM;
3812
3813         msec->msg = msg;
3814         msec->sid = SECINITSID_UNLABELED;
3815         msg->security = msec;
3816
3817         return 0;
3818 }
3819
3820 static void msg_msg_free_security(struct msg_msg *msg)
3821 {
3822         struct msg_security_struct *msec = msg->security;
3823
3824         msg->security = NULL;
3825         kfree(msec);
3826 }
3827
3828 static int ipc_has_perm(struct kern_ipc_perm *ipc_perms,
3829                         u32 perms)
3830 {
3831         struct task_security_struct *tsec;
3832         struct ipc_security_struct *isec;
3833         struct avc_audit_data ad;
3834
3835         tsec = current->security;
3836         isec = ipc_perms->security;
3837
3838         AVC_AUDIT_DATA_INIT(&ad, IPC);
3839         ad.u.ipc_id = ipc_perms->key;
3840
3841         return avc_has_perm(tsec->sid, isec->sid, isec->sclass, perms, &ad);
3842 }
3843
3844 static int selinux_msg_msg_alloc_security(struct msg_msg *msg)
3845 {
3846         return msg_msg_alloc_security(msg);
3847 }
3848
3849 static void selinux_msg_msg_free_security(struct msg_msg *msg)
3850 {
3851         msg_msg_free_security(msg);
3852 }
3853
3854 /* message queue security operations */
3855 static int selinux_msg_queue_alloc_security(struct msg_queue *msq)
3856 {
3857         struct task_security_struct *tsec;
3858         struct ipc_security_struct *isec;
3859         struct avc_audit_data ad;
3860         int rc;
3861
3862         rc = ipc_alloc_security(current, &msq->q_perm, SECCLASS_MSGQ);
3863         if (rc)
3864                 return rc;
3865
3866         tsec = current->security;
3867         isec = msq->q_perm.security;
3868
3869         AVC_AUDIT_DATA_INIT(&ad, IPC);
3870         ad.u.ipc_id = msq->q_perm.key;
3871
3872         rc = avc_has_perm(tsec->sid, isec->sid, SECCLASS_MSGQ,
3873                           MSGQ__CREATE, &ad);
3874         if (rc) {
3875                 ipc_free_security(&msq->q_perm);
3876                 return rc;
3877         }
3878         return 0;
3879 }
3880
3881 static void selinux_msg_queue_free_security(struct msg_queue *msq)
3882 {
3883         ipc_free_security(&msq->q_perm);
3884 }
3885
3886 static int selinux_msg_queue_associate(struct msg_queue *msq, int msqflg)
3887 {
3888         struct task_security_struct *tsec;
3889         struct ipc_security_struct *isec;
3890         struct avc_audit_data ad;
3891
3892         tsec = current->security;
3893         isec = msq->q_perm.security;
3894
3895         AVC_AUDIT_DATA_INIT(&ad, IPC);
3896         ad.u.ipc_id = msq->q_perm.key;
3897
3898         return avc_has_perm(tsec->sid, isec->sid, SECCLASS_MSGQ,
3899                             MSGQ__ASSOCIATE, &ad);
3900 }
3901
3902 static int selinux_msg_queue_msgctl(struct msg_queue *msq, int cmd)
3903 {
3904         int err;
3905         int perms;
3906
3907         switch(cmd) {
3908         case IPC_INFO:
3909         case MSG_INFO:
3910                 /* No specific object, just general system-wide information. */
3911                 return task_has_system(current, SYSTEM__IPC_INFO);
3912         case IPC_STAT:
3913         case MSG_STAT:
3914                 perms = MSGQ__GETATTR | MSGQ__ASSOCIATE;
3915                 break;
3916         case IPC_SET:
3917                 perms = MSGQ__SETATTR;
3918                 break;
3919         case IPC_RMID:
3920                 perms = MSGQ__DESTROY;
3921                 break;
3922         default:
3923                 return 0;
3924         }
3925
3926         err = ipc_has_perm(&msq->q_perm, perms);
3927         return err;
3928 }
3929
3930 static int selinux_msg_queue_msgsnd(struct msg_queue *msq, struct msg_msg *msg, int msqflg)
3931 {
3932         struct task_security_struct *tsec;
3933         struct ipc_security_struct *isec;
3934         struct msg_security_struct *msec;
3935         struct avc_audit_data ad;
3936         int rc;
3937
3938         tsec = current->security;
3939         isec = msq->q_perm.security;
3940         msec = msg->security;
3941
3942         /*
3943          * First time through, need to assign label to the message
3944          */
3945         if (msec->sid == SECINITSID_UNLABELED) {
3946                 /*
3947                  * Compute new sid based on current process and
3948                  * message queue this message will be stored in
3949                  */
3950                 rc = security_transition_sid(tsec->sid,
3951                                              isec->sid,
3952                                              SECCLASS_MSG,
3953                                              &msec->sid);
3954                 if (rc)
3955                         return rc;
3956         }
3957
3958         AVC_AUDIT_DATA_INIT(&ad, IPC);
3959         ad.u.ipc_id = msq->q_perm.key;
3960
3961         /* Can this process write to the queue? */
3962         rc = avc_has_perm(tsec->sid, isec->sid, SECCLASS_MSGQ,
3963                           MSGQ__WRITE, &ad);
3964         if (!rc)
3965                 /* Can this process send the message */
3966                 rc = avc_has_perm(tsec->sid, msec->sid,
3967                                   SECCLASS_MSG, MSG__SEND, &ad);
3968         if (!rc)
3969                 /* Can the message be put in the queue? */
3970                 rc = avc_has_perm(msec->sid, isec->sid,
3971                                   SECCLASS_MSGQ, MSGQ__ENQUEUE, &ad);
3972
3973         return rc;
3974 }
3975
3976 static int selinux_msg_queue_msgrcv(struct msg_queue *msq, struct msg_msg *msg,
3977                                     struct task_struct *target,
3978                                     long type, int mode)
3979 {
3980         struct task_security_struct *tsec;
3981         struct ipc_security_struct *isec;
3982         struct msg_security_struct *msec;
3983         struct avc_audit_data ad;
3984         int rc;
3985
3986         tsec = target->security;
3987         isec = msq->q_perm.security;
3988         msec = msg->security;
3989
3990         AVC_AUDIT_DATA_INIT(&ad, IPC);
3991         ad.u.ipc_id = msq->q_perm.key;
3992
3993         rc = avc_has_perm(tsec->sid, isec->sid,
3994                           SECCLASS_MSGQ, MSGQ__READ, &ad);
3995         if (!rc)
3996                 rc = avc_has_perm(tsec->sid, msec->sid,
3997                                   SECCLASS_MSG, MSG__RECEIVE, &ad);
3998         return rc;
3999 }
4000
4001 /* Shared Memory security operations */
4002 static int selinux_shm_alloc_security(struct shmid_kernel *shp)
4003 {
4004         struct task_security_struct *tsec;
4005         struct ipc_security_struct *isec;
4006         struct avc_audit_data ad;
4007         int rc;
4008
4009         rc = ipc_alloc_security(current, &shp->shm_perm, SECCLASS_SHM);
4010         if (rc)
4011                 return rc;
4012
4013         tsec = current->security;
4014         isec = shp->shm_perm.security;
4015
4016         AVC_AUDIT_DATA_INIT(&ad, IPC);
4017         ad.u.ipc_id = shp->shm_perm.key;
4018
4019         rc = avc_has_perm(tsec->sid, isec->sid, SECCLASS_SHM,
4020                           SHM__CREATE, &ad);
4021         if (rc) {
4022                 ipc_free_security(&shp->shm_perm);
4023                 return rc;
4024         }
4025         return 0;
4026 }
4027
4028 static void selinux_shm_free_security(struct shmid_kernel *shp)
4029 {
4030         ipc_free_security(&shp->shm_perm);
4031 }
4032
4033 static int selinux_shm_associate(struct shmid_kernel *shp, int shmflg)
4034 {
4035         struct task_security_struct *tsec;
4036         struct ipc_security_struct *isec;
4037         struct avc_audit_data ad;
4038
4039         tsec = current->security;
4040         isec = shp->shm_perm.security;
4041
4042         AVC_AUDIT_DATA_INIT(&ad, IPC);
4043         ad.u.ipc_id = shp->shm_perm.key;
4044
4045         return avc_has_perm(tsec->sid, isec->sid, SECCLASS_SHM,
4046                             SHM__ASSOCIATE, &ad);
4047 }
4048
4049 /* Note, at this point, shp is locked down */
4050 static int selinux_shm_shmctl(struct shmid_kernel *shp, int cmd)
4051 {
4052         int perms;
4053         int err;
4054
4055         switch(cmd) {
4056         case IPC_INFO:
4057         case SHM_INFO:
4058                 /* No specific object, just general system-wide information. */
4059                 return task_has_system(current, SYSTEM__IPC_INFO);
4060         case IPC_STAT:
4061         case SHM_STAT:
4062                 perms = SHM__GETATTR | SHM__ASSOCIATE;
4063                 break;
4064         case IPC_SET:
4065                 perms = SHM__SETATTR;
4066                 break;
4067         case SHM_LOCK:
4068         case SHM_UNLOCK:
4069                 perms = SHM__LOCK;
4070                 break;
4071         case IPC_RMID:
4072                 perms = SHM__DESTROY;
4073                 break;
4074         default:
4075                 return 0;
4076         }
4077
4078         err = ipc_has_perm(&shp->shm_perm, perms);
4079         return err;
4080 }
4081
4082 static int selinux_shm_shmat(struct shmid_kernel *shp,
4083                              char __user *shmaddr, int shmflg)
4084 {
4085         u32 perms;
4086         int rc;
4087
4088         rc = secondary_ops->shm_shmat(shp, shmaddr, shmflg);
4089         if (rc)
4090                 return rc;
4091
4092         if (shmflg & SHM_RDONLY)
4093                 perms = SHM__READ;
4094         else
4095                 perms = SHM__READ | SHM__WRITE;
4096
4097         return ipc_has_perm(&shp->shm_perm, perms);
4098 }
4099
4100 /* Semaphore security operations */
4101 static int selinux_sem_alloc_security(struct sem_array *sma)
4102 {
4103         struct task_security_struct *tsec;
4104         struct ipc_security_struct *isec;
4105         struct avc_audit_data ad;
4106         int rc;
4107
4108         rc = ipc_alloc_security(current, &sma->sem_perm, SECCLASS_SEM);
4109         if (rc)
4110                 return rc;
4111
4112         tsec = current->security;
4113         isec = sma->sem_perm.security;
4114
4115         AVC_AUDIT_DATA_INIT(&ad, IPC);
4116         ad.u.ipc_id = sma->sem_perm.key;
4117
4118         rc = avc_has_perm(tsec->sid, isec->sid, SECCLASS_SEM,
4119                           SEM__CREATE, &ad);
4120         if (rc) {
4121                 ipc_free_security(&sma->sem_perm);
4122                 return rc;
4123         }
4124         return 0;
4125 }
4126
4127 static void selinux_sem_free_security(struct sem_array *sma)
4128 {
4129         ipc_free_security(&sma->sem_perm);
4130 }
4131
4132 static int selinux_sem_associate(struct sem_array *sma, int semflg)
4133 {
4134         struct task_security_struct *tsec;
4135         struct ipc_security_struct *isec;
4136         struct avc_audit_data ad;
4137
4138         tsec = current->security;
4139         isec = sma->sem_perm.security;
4140
4141         AVC_AUDIT_DATA_INIT(&ad, IPC);
4142         ad.u.ipc_id = sma->sem_perm.key;
4143
4144         return avc_has_perm(tsec->sid, isec->sid, SECCLASS_SEM,
4145                             SEM__ASSOCIATE, &ad);
4146 }
4147
4148 /* Note, at this point, sma is locked down */
4149 static int selinux_sem_semctl(struct sem_array *sma, int cmd)
4150 {
4151         int err;
4152         u32 perms;
4153
4154         switch(cmd) {
4155         case IPC_INFO:
4156         case SEM_INFO:
4157                 /* No specific object, just general system-wide information. */
4158                 return task_has_system(current, SYSTEM__IPC_INFO);
4159         case GETPID:
4160         case GETNCNT:
4161         case GETZCNT:
4162                 perms = SEM__GETATTR;
4163                 break;
4164         case GETVAL:
4165         case GETALL:
4166                 perms = SEM__READ;
4167                 break;
4168         case SETVAL:
4169         case SETALL:
4170                 perms = SEM__WRITE;
4171                 break;
4172         case IPC_RMID:
4173                 perms = SEM__DESTROY;
4174                 break;
4175         case IPC_SET:
4176                 perms = SEM__SETATTR;
4177                 break;
4178         case IPC_STAT:
4179         case SEM_STAT:
4180                 perms = SEM__GETATTR | SEM__ASSOCIATE;
4181                 break;
4182         default:
4183                 return 0;
4184         }
4185
4186         err = ipc_has_perm(&sma->sem_perm, perms);
4187         return err;
4188 }
4189
4190 static int selinux_sem_semop(struct sem_array *sma,
4191                              struct sembuf *sops, unsigned nsops, int alter)
4192 {
4193         u32 perms;
4194
4195         if (alter)
4196                 perms = SEM__READ | SEM__WRITE;
4197         else
4198                 perms = SEM__READ;
4199
4200         return ipc_has_perm(&sma->sem_perm, perms);
4201 }
4202
4203 static int selinux_ipc_permission(struct kern_ipc_perm *ipcp, short flag)
4204 {
4205         u32 av = 0;
4206
4207         av = 0;
4208         if (flag & S_IRUGO)
4209                 av |= IPC__UNIX_READ;
4210         if (flag & S_IWUGO)
4211                 av |= IPC__UNIX_WRITE;
4212
4213         if (av == 0)
4214                 return 0;
4215
4216         return ipc_has_perm(ipcp, av);
4217 }
4218
4219 /* module stacking operations */
4220 static int selinux_register_security (const char *name, struct security_operations *ops)
4221 {
4222         if (secondary_ops != original_ops) {
4223                 printk(KERN_INFO "%s:  There is already a secondary security "
4224                        "module registered.\n", __FUNCTION__);
4225                 return -EINVAL;
4226         }
4227
4228         secondary_ops = ops;
4229
4230         printk(KERN_INFO "%s:  Registering secondary module %s\n",
4231                __FUNCTION__,
4232                name);
4233
4234         return 0;
4235 }
4236
4237 static int selinux_unregister_security (const char *name, struct security_operations *ops)
4238 {
4239         if (ops != secondary_ops) {
4240                 printk (KERN_INFO "%s:  trying to unregister a security module "
4241                         "that is not registered.\n", __FUNCTION__);
4242                 return -EINVAL;
4243         }
4244
4245         secondary_ops = original_ops;
4246
4247         return 0;
4248 }
4249
4250 static void selinux_d_instantiate (struct dentry *dentry, struct inode *inode)
4251 {
4252         if (inode)
4253                 inode_doinit_with_dentry(inode, dentry);
4254 }
4255
4256 static int selinux_getprocattr(struct task_struct *p,
4257                                char *name, void *value, size_t size)
4258 {
4259         struct task_security_struct *tsec;
4260         u32 sid;
4261         int error;
4262
4263         if (current != p) {
4264                 error = task_has_perm(current, p, PROCESS__GETATTR);
4265                 if (error)
4266                         return error;
4267         }
4268
4269         tsec = p->security;
4270
4271         if (!strcmp(name, "current"))
4272                 sid = tsec->sid;
4273         else if (!strcmp(name, "prev"))
4274                 sid = tsec->osid;
4275         else if (!strcmp(name, "exec"))
4276                 sid = tsec->exec_sid;
4277         else if (!strcmp(name, "fscreate"))
4278                 sid = tsec->create_sid;
4279         else if (!strcmp(name, "keycreate"))
4280                 sid = tsec->keycreate_sid;
4281         else if (!strcmp(name, "sockcreate"))
4282                 sid = tsec->sockcreate_sid;
4283         else
4284                 return -EINVAL;
4285
4286         if (!sid)
4287                 return 0;
4288
4289         return selinux_getsecurity(sid, value, size);
4290 }
4291
4292 static int selinux_setprocattr(struct task_struct *p,
4293                                char *name, void *value, size_t size)
4294 {
4295         struct task_security_struct *tsec;
4296         u32 sid = 0;
4297         int error;
4298         char *str = value;
4299
4300         if (current != p) {
4301                 /* SELinux only allows a process to change its own
4302                    security attributes. */
4303                 return -EACCES;
4304         }
4305
4306         /*
4307          * Basic control over ability to set these attributes at all.
4308          * current == p, but we'll pass them separately in case the
4309          * above restriction is ever removed.
4310          */
4311         if (!strcmp(name, "exec"))
4312                 error = task_has_perm(current, p, PROCESS__SETEXEC);
4313         else if (!strcmp(name, "fscreate"))
4314                 error = task_has_perm(current, p, PROCESS__SETFSCREATE);
4315         else if (!strcmp(name, "keycreate"))
4316                 error = task_has_perm(current, p, PROCESS__SETKEYCREATE);
4317         else if (!strcmp(name, "sockcreate"))
4318                 error = task_has_perm(current, p, PROCESS__SETSOCKCREATE);
4319         else if (!strcmp(name, "current"))
4320                 error = task_has_perm(current, p, PROCESS__SETCURRENT);
4321         else
4322                 error = -EINVAL;
4323         if (error)
4324                 return error;
4325
4326         /* Obtain a SID for the context, if one was specified. */
4327         if (size && str[1] && str[1] != '\n') {
4328                 if (str[size-1] == '\n') {
4329                         str[size-1] = 0;
4330                         size--;
4331                 }
4332                 error = security_context_to_sid(value, size, &sid);
4333                 if (error)
4334                         return error;
4335         }
4336
4337         /* Permission checking based on the specified context is
4338            performed during the actual operation (execve,
4339            open/mkdir/...), when we know the full context of the
4340            operation.  See selinux_bprm_set_security for the execve
4341            checks and may_create for the file creation checks. The
4342            operation will then fail if the context is not permitted. */
4343         tsec = p->security;
4344         if (!strcmp(name, "exec"))
4345                 tsec->exec_sid = sid;
4346         else if (!strcmp(name, "fscreate"))
4347                 tsec->create_sid = sid;
4348         else if (!strcmp(name, "keycreate")) {
4349                 error = may_create_key(sid, p);
4350                 if (error)
4351                         return error;
4352                 tsec->keycreate_sid = sid;
4353         } else if (!strcmp(name, "sockcreate"))
4354                 tsec->sockcreate_sid = sid;
4355         else if (!strcmp(name, "current")) {
4356                 struct av_decision avd;
4357
4358                 if (sid == 0)
4359                         return -EINVAL;
4360
4361                 /* Only allow single threaded processes to change context */
4362                 if (atomic_read(&p->mm->mm_users) != 1) {
4363                         struct task_struct *g, *t;
4364                         struct mm_struct *mm = p->mm;
4365                         read_lock(&tasklist_lock);
4366                         do_each_thread(g, t)
4367                                 if (t->mm == mm && t != p) {
4368                                         read_unlock(&tasklist_lock);
4369                                         return -EPERM;
4370                                 }
4371                         while_each_thread(g, t);
4372                         read_unlock(&tasklist_lock);
4373                 }
4374
4375                 /* Check permissions for the transition. */
4376                 error = avc_has_perm(tsec->sid, sid, SECCLASS_PROCESS,
4377                                      PROCESS__DYNTRANSITION, NULL);
4378                 if (error)
4379                         return error;
4380
4381                 /* Check for ptracing, and update the task SID if ok.
4382                    Otherwise, leave SID unchanged and fail. */
4383                 task_lock(p);
4384                 if (p->ptrace & PT_PTRACED) {
4385                         error = avc_has_perm_noaudit(tsec->ptrace_sid, sid,
4386                                                      SECCLASS_PROCESS,
4387                                                      PROCESS__PTRACE, &avd);
4388                         if (!error)
4389                                 tsec->sid = sid;
4390                         task_unlock(p);
4391                         avc_audit(tsec->ptrace_sid, sid, SECCLASS_PROCESS,
4392                                   PROCESS__PTRACE, &avd, error, NULL);
4393                         if (error)
4394                                 return error;
4395                 } else {
4396                         tsec->sid = sid;
4397                         task_unlock(p);
4398                 }
4399         }
4400         else
4401                 return -EINVAL;
4402
4403         return size;
4404 }
4405
4406 static int selinux_secid_to_secctx(u32 secid, char **secdata, u32 *seclen)
4407 {
4408         return security_sid_to_context(secid, secdata, seclen);
4409 }
4410
4411 static void selinux_release_secctx(char *secdata, u32 seclen)
4412 {
4413         if (secdata)
4414                 kfree(secdata);
4415 }
4416
4417 #ifdef CONFIG_KEYS
4418
4419 static int selinux_key_alloc(struct key *k, struct task_struct *tsk,
4420                              unsigned long flags)
4421 {
4422         struct task_security_struct *tsec = tsk->security;
4423         struct key_security_struct *ksec;
4424
4425         ksec = kzalloc(sizeof(struct key_security_struct), GFP_KERNEL);
4426         if (!ksec)
4427                 return -ENOMEM;
4428
4429         ksec->obj = k;
4430         if (tsec->keycreate_sid)
4431                 ksec->sid = tsec->keycreate_sid;
4432         else
4433                 ksec->sid = tsec->sid;
4434         k->security = ksec;
4435
4436         return 0;
4437 }
4438
4439 static void selinux_key_free(struct key *k)
4440 {
4441         struct key_security_struct *ksec = k->security;
4442
4443         k->security = NULL;
4444         kfree(ksec);
4445 }
4446
4447 static int selinux_key_permission(key_ref_t key_ref,
4448                             struct task_struct *ctx,
4449                             key_perm_t perm)
4450 {
4451         struct key *key;
4452         struct task_security_struct *tsec;
4453         struct key_security_struct *ksec;
4454
4455         key = key_ref_to_ptr(key_ref);
4456
4457         tsec = ctx->security;
4458         ksec = key->security;
4459
4460         /* if no specific permissions are requested, we skip the
4461            permission check. No serious, additional covert channels
4462            appear to be created. */
4463         if (perm == 0)
4464                 return 0;
4465
4466         return avc_has_perm(tsec->sid, ksec->sid,
4467                             SECCLASS_KEY, perm, NULL);
4468 }
4469
4470 #endif
4471
4472 static struct security_operations selinux_ops = {
4473         .ptrace =                       selinux_ptrace,
4474         .capget =                       selinux_capget,
4475         .capset_check =                 selinux_capset_check,
4476         .capset_set =                   selinux_capset_set,
4477         .sysctl =                       selinux_sysctl,
4478         .capable =                      selinux_capable,
4479         .quotactl =                     selinux_quotactl,
4480         .quota_on =                     selinux_quota_on,
4481         .syslog =                       selinux_syslog,
4482         .vm_enough_memory =             selinux_vm_enough_memory,
4483
4484         .netlink_send =                 selinux_netlink_send,
4485         .netlink_recv =                 selinux_netlink_recv,
4486
4487         .bprm_alloc_security =          selinux_bprm_alloc_security,
4488         .bprm_free_security =           selinux_bprm_free_security,
4489         .bprm_apply_creds =             selinux_bprm_apply_creds,
4490         .bprm_post_apply_creds =        selinux_bprm_post_apply_creds,
4491         .bprm_set_security =            selinux_bprm_set_security,
4492         .bprm_check_security =          selinux_bprm_check_security,
4493         .bprm_secureexec =              selinux_bprm_secureexec,
4494
4495         .sb_alloc_security =            selinux_sb_alloc_security,
4496         .sb_free_security =             selinux_sb_free_security,
4497         .sb_copy_data =                 selinux_sb_copy_data,
4498         .sb_kern_mount =                selinux_sb_kern_mount,
4499         .sb_statfs =                    selinux_sb_statfs,
4500         .sb_mount =                     selinux_mount,
4501         .sb_umount =                    selinux_umount,
4502
4503         .inode_alloc_security =         selinux_inode_alloc_security,
4504         .inode_free_security =          selinux_inode_free_security,
4505         .inode_init_security =          selinux_inode_init_security,
4506         .inode_create =                 selinux_inode_create,
4507         .inode_link =                   selinux_inode_link,
4508         .inode_unlink =                 selinux_inode_unlink,
4509         .inode_symlink =                selinux_inode_symlink,
4510         .inode_mkdir =                  selinux_inode_mkdir,
4511         .inode_rmdir =                  selinux_inode_rmdir,
4512         .inode_mknod =                  selinux_inode_mknod,
4513         .inode_rename =                 selinux_inode_rename,
4514         .inode_readlink =               selinux_inode_readlink,
4515         .inode_follow_link =            selinux_inode_follow_link,
4516         .inode_permission =             selinux_inode_permission,
4517         .inode_setattr =                selinux_inode_setattr,
4518         .inode_getattr =                selinux_inode_getattr,
4519         .inode_setxattr =               selinux_inode_setxattr,
4520         .inode_post_setxattr =          selinux_inode_post_setxattr,
4521         .inode_getxattr =               selinux_inode_getxattr,
4522         .inode_listxattr =              selinux_inode_listxattr,
4523         .inode_removexattr =            selinux_inode_removexattr,
4524         .inode_xattr_getsuffix =        selinux_inode_xattr_getsuffix,
4525         .inode_getsecurity =            selinux_inode_getsecurity,
4526         .inode_setsecurity =            selinux_inode_setsecurity,
4527         .inode_listsecurity =           selinux_inode_listsecurity,
4528
4529         .file_permission =              selinux_file_permission,
4530         .file_alloc_security =          selinux_file_alloc_security,
4531         .file_free_security =           selinux_file_free_security,
4532         .file_ioctl =                   selinux_file_ioctl,
4533         .file_mmap =                    selinux_file_mmap,
4534         .file_mprotect =                selinux_file_mprotect,
4535         .file_lock =                    selinux_file_lock,
4536         .file_fcntl =                   selinux_file_fcntl,
4537         .file_set_fowner =              selinux_file_set_fowner,
4538         .file_send_sigiotask =          selinux_file_send_sigiotask,
4539         .file_receive =                 selinux_file_receive,
4540
4541         .task_create =                  selinux_task_create,
4542         .task_alloc_security =          selinux_task_alloc_security,
4543         .task_free_security =           selinux_task_free_security,
4544         .task_setuid =                  selinux_task_setuid,
4545         .task_post_setuid =             selinux_task_post_setuid,
4546         .task_setgid =                  selinux_task_setgid,
4547         .task_setpgid =                 selinux_task_setpgid,
4548         .task_getpgid =                 selinux_task_getpgid,
4549         .task_getsid =                  selinux_task_getsid,
4550         .task_getsecid =                selinux_task_getsecid,
4551         .task_setgroups =               selinux_task_setgroups,
4552         .task_setnice =                 selinux_task_setnice,
4553         .task_setioprio =               selinux_task_setioprio,
4554         .task_getioprio =               selinux_task_getioprio,
4555         .task_setrlimit =               selinux_task_setrlimit,
4556         .task_setscheduler =            selinux_task_setscheduler,
4557         .task_getscheduler =            selinux_task_getscheduler,
4558         .task_movememory =              selinux_task_movememory,
4559         .task_kill =                    selinux_task_kill,
4560         .task_wait =                    selinux_task_wait,
4561         .task_prctl =                   selinux_task_prctl,
4562         .task_reparent_to_init =        selinux_task_reparent_to_init,
4563         .task_to_inode =                selinux_task_to_inode,
4564
4565         .ipc_permission =               selinux_ipc_permission,
4566
4567         .msg_msg_alloc_security =       selinux_msg_msg_alloc_security,
4568         .msg_msg_free_security =        selinux_msg_msg_free_security,
4569
4570         .msg_queue_alloc_security =     selinux_msg_queue_alloc_security,
4571         .msg_queue_free_security =      selinux_msg_queue_free_security,
4572         .msg_queue_associate =          selinux_msg_queue_associate,
4573         .msg_queue_msgctl =             selinux_msg_queue_msgctl,
4574         .msg_queue_msgsnd =             selinux_msg_queue_msgsnd,
4575         .msg_queue_msgrcv =             selinux_msg_queue_msgrcv,
4576
4577         .shm_alloc_security =           selinux_shm_alloc_security,
4578         .shm_free_security =            selinux_shm_free_security,
4579         .shm_associate =                selinux_shm_associate,
4580         .shm_shmctl =                   selinux_shm_shmctl,
4581         .shm_shmat =                    selinux_shm_shmat,
4582
4583         .sem_alloc_security =           selinux_sem_alloc_security,
4584         .sem_free_security =            selinux_sem_free_security,
4585         .sem_associate =                selinux_sem_associate,
4586         .sem_semctl =                   selinux_sem_semctl,
4587         .sem_semop =                    selinux_sem_semop,
4588
4589         .register_security =            selinux_register_security,
4590         .unregister_security =          selinux_unregister_security,
4591
4592         .d_instantiate =                selinux_d_instantiate,
4593
4594         .getprocattr =                  selinux_getprocattr,
4595         .setprocattr =                  selinux_setprocattr,
4596
4597         .secid_to_secctx =              selinux_secid_to_secctx,
4598         .release_secctx =               selinux_release_secctx,
4599
4600         .unix_stream_connect =          selinux_socket_unix_stream_connect,
4601         .unix_may_send =                selinux_socket_unix_may_send,
4602
4603         .socket_create =                selinux_socket_create,
4604         .socket_post_create =           selinux_socket_post_create,
4605         .socket_bind =                  selinux_socket_bind,
4606         .socket_connect =               selinux_socket_connect,
4607         .socket_listen =                selinux_socket_listen,
4608         .socket_accept =                selinux_socket_accept,
4609         .socket_sendmsg =               selinux_socket_sendmsg,
4610         .socket_recvmsg =               selinux_socket_recvmsg,
4611         .socket_getsockname =           selinux_socket_getsockname,
4612         .socket_getpeername =           selinux_socket_getpeername,
4613         .socket_getsockopt =            selinux_socket_getsockopt,
4614         .socket_setsockopt =            selinux_socket_setsockopt,
4615         .socket_shutdown =              selinux_socket_shutdown,
4616         .socket_sock_rcv_skb =          selinux_socket_sock_rcv_skb,
4617         .socket_getpeersec_stream =     selinux_socket_getpeersec_stream,
4618         .socket_getpeersec_dgram =      selinux_socket_getpeersec_dgram,
4619         .sk_alloc_security =            selinux_sk_alloc_security,
4620         .sk_free_security =             selinux_sk_free_security,
4621         .sk_getsid =                    selinux_sk_getsid_security,
4622
4623 #ifdef CONFIG_SECURITY_NETWORK_XFRM
4624         .xfrm_policy_alloc_security =   selinux_xfrm_policy_alloc,
4625         .xfrm_policy_clone_security =   selinux_xfrm_policy_clone,
4626         .xfrm_policy_free_security =    selinux_xfrm_policy_free,
4627         .xfrm_policy_delete_security =  selinux_xfrm_policy_delete,
4628         .xfrm_state_alloc_security =    selinux_xfrm_state_alloc,
4629         .xfrm_state_free_security =     selinux_xfrm_state_free,
4630         .xfrm_state_delete_security =   selinux_xfrm_state_delete,
4631         .xfrm_policy_lookup =           selinux_xfrm_policy_lookup,
4632 #endif
4633
4634 #ifdef CONFIG_KEYS
4635         .key_alloc =                    selinux_key_alloc,
4636         .key_free =                     selinux_key_free,
4637         .key_permission =               selinux_key_permission,
4638 #endif
4639 };
4640
4641 static __init int selinux_init(void)
4642 {
4643         struct task_security_struct *tsec;
4644
4645         if (!selinux_enabled) {
4646                 printk(KERN_INFO "SELinux:  Disabled at boot.\n");
4647                 return 0;
4648         }
4649
4650         printk(KERN_INFO "SELinux:  Initializing.\n");
4651
4652         /* Set the security state for the initial task. */
4653         if (task_alloc_security(current))
4654                 panic("SELinux:  Failed to initialize initial task.\n");
4655         tsec = current->security;
4656         tsec->osid = tsec->sid = SECINITSID_KERNEL;
4657
4658         sel_inode_cache = kmem_cache_create("selinux_inode_security",
4659                                             sizeof(struct inode_security_struct),
4660                                             0, SLAB_PANIC, NULL, NULL);
4661         avc_init();
4662
4663         original_ops = secondary_ops = security_ops;
4664         if (!secondary_ops)
4665                 panic ("SELinux: No initial security operations\n");
4666         if (register_security (&selinux_ops))
4667                 panic("SELinux: Unable to register with kernel.\n");
4668
4669         if (selinux_enforcing) {
4670                 printk(KERN_INFO "SELinux:  Starting in enforcing mode\n");
4671         } else {
4672                 printk(KERN_INFO "SELinux:  Starting in permissive mode\n");
4673         }
4674
4675 #ifdef CONFIG_KEYS
4676         /* Add security information to initial keyrings */
4677         selinux_key_alloc(&root_user_keyring, current,
4678                           KEY_ALLOC_NOT_IN_QUOTA);
4679         selinux_key_alloc(&root_session_keyring, current,
4680                           KEY_ALLOC_NOT_IN_QUOTA);
4681 #endif
4682
4683         return 0;
4684 }
4685
4686 void selinux_complete_init(void)
4687 {
4688         printk(KERN_INFO "SELinux:  Completing initialization.\n");
4689
4690         /* Set up any superblocks initialized prior to the policy load. */
4691         printk(KERN_INFO "SELinux:  Setting up existing superblocks.\n");
4692         spin_lock(&sb_lock);
4693         spin_lock(&sb_security_lock);
4694 next_sb:
4695         if (!list_empty(&superblock_security_head)) {
4696                 struct superblock_security_struct *sbsec =
4697                                 list_entry(superblock_security_head.next,
4698                                            struct superblock_security_struct,
4699                                            list);
4700                 struct super_block *sb = sbsec->sb;
4701                 sb->s_count++;
4702                 spin_unlock(&sb_security_lock);
4703                 spin_unlock(&sb_lock);
4704                 down_read(&sb->s_umount);
4705                 if (sb->s_root)
4706                         superblock_doinit(sb, NULL);
4707                 drop_super(sb);
4708                 spin_lock(&sb_lock);
4709                 spin_lock(&sb_security_lock);
4710                 list_del_init(&sbsec->list);
4711                 goto next_sb;
4712         }
4713         spin_unlock(&sb_security_lock);
4714         spin_unlock(&sb_lock);
4715 }
4716
4717 /* SELinux requires early initialization in order to label
4718    all processes and objects when they are created. */
4719 security_initcall(selinux_init);
4720
4721 #if defined(CONFIG_NETFILTER)
4722
4723 static struct nf_hook_ops selinux_ipv4_op = {
4724         .hook =         selinux_ipv4_postroute_last,
4725         .owner =        THIS_MODULE,
4726         .pf =           PF_INET,
4727         .hooknum =      NF_IP_POST_ROUTING,
4728         .priority =     NF_IP_PRI_SELINUX_LAST,
4729 };
4730
4731 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
4732
4733 static struct nf_hook_ops selinux_ipv6_op = {
4734         .hook =         selinux_ipv6_postroute_last,
4735         .owner =        THIS_MODULE,
4736         .pf =           PF_INET6,
4737         .hooknum =      NF_IP6_POST_ROUTING,
4738         .priority =     NF_IP6_PRI_SELINUX_LAST,
4739 };
4740
4741 #endif  /* IPV6 */
4742
4743 static int __init selinux_nf_ip_init(void)
4744 {
4745         int err = 0;
4746
4747         if (!selinux_enabled)
4748                 goto out;
4749
4750         printk(KERN_INFO "SELinux:  Registering netfilter hooks\n");
4751
4752         err = nf_register_hook(&selinux_ipv4_op);
4753         if (err)
4754                 panic("SELinux: nf_register_hook for IPv4: error %d\n", err);
4755
4756 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
4757
4758         err = nf_register_hook(&selinux_ipv6_op);
4759         if (err)
4760                 panic("SELinux: nf_register_hook for IPv6: error %d\n", err);
4761
4762 #endif  /* IPV6 */
4763
4764 out:
4765         return err;
4766 }
4767
4768 __initcall(selinux_nf_ip_init);
4769
4770 #ifdef CONFIG_SECURITY_SELINUX_DISABLE
4771 static void selinux_nf_ip_exit(void)
4772 {
4773         printk(KERN_INFO "SELinux:  Unregistering netfilter hooks\n");
4774
4775         nf_unregister_hook(&selinux_ipv4_op);
4776 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
4777         nf_unregister_hook(&selinux_ipv6_op);
4778 #endif  /* IPV6 */
4779 }
4780 #endif
4781
4782 #else /* CONFIG_NETFILTER */
4783
4784 #ifdef CONFIG_SECURITY_SELINUX_DISABLE
4785 #define selinux_nf_ip_exit()
4786 #endif
4787
4788 #endif /* CONFIG_NETFILTER */
4789
4790 #ifdef CONFIG_SECURITY_SELINUX_DISABLE
4791 int selinux_disable(void)
4792 {
4793         extern void exit_sel_fs(void);
4794         static int selinux_disabled = 0;
4795
4796         if (ss_initialized) {
4797                 /* Not permitted after initial policy load. */
4798                 return -EINVAL;
4799         }
4800
4801         if (selinux_disabled) {
4802                 /* Only do this once. */
4803                 return -EINVAL;
4804         }
4805
4806         printk(KERN_INFO "SELinux:  Disabled at runtime.\n");
4807
4808         selinux_disabled = 1;
4809         selinux_enabled = 0;
4810
4811         /* Reset security_ops to the secondary module, dummy or capability. */
4812         security_ops = secondary_ops;
4813
4814         /* Unregister netfilter hooks. */
4815         selinux_nf_ip_exit();
4816
4817         /* Unregister selinuxfs. */
4818         exit_sel_fs();
4819
4820         return 0;
4821 }
4822 #endif
4823
4824