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, <[email protected]>
   7  *            Chris Vance, <[email protected]>
   8  *            Wayne Salamon, <[email protected]>
   9  *            James Morris <[email protected]>
  10  *
  11  *  Copyright (C) 2001,2002 Networks Associates Technology, Inc.
  12  *  Copyright (C) 2003-2008 Red Hat, Inc., James Morris <[email protected]>
  13  *                                         Eric Paris <[email protected]>
  14  *  Copyright (C) 2004-2005 Trusted Computer Solutions, Inc.
  15  *                          <[email protected]>
  16  *  Copyright (C) 2006, 2007, 2009 Hewlett-Packard Development Company, L.P.
  17  *      Paul Moore <[email protected]>
  18  *  Copyright (C) 2007 Hitachi Software Engineering Co., Ltd.
  19  *                     Yuichi Nakamura <[email protected]>
  20  *
  21  *      This program is free software; you can redistribute it and/or modify
  22  *      it under the terms of the GNU General Public License version 2,
  23  *      as published by the Free Software Foundation.
  24  */
  25
  26 #include <linux/init.h>
  27 #include <linux/kd.h>
  28 #include <linux/kernel.h>
  29 #include <linux/tracehook.h>
  30 #include <linux/errno.h>
  31 #include <linux/sched.h>
  32 #include <linux/security.h>
  33 #include <linux/xattr.h>
  34 #include <linux/capability.h>
  35 #include <linux/unistd.h>
  36 #include <linux/mm.h>
  37 #include <linux/mman.h>
  38 #include <linux/slab.h>
  39 #include <linux/pagemap.h>
  40 #include <linux/proc_fs.h>
  41 #include <linux/swap.h>
  42 #include <linux/spinlock.h>
  43 #include <linux/syscalls.h>
  44 #include <linux/dcache.h>
  45 #include <linux/file.h>
  46 #include <linux/fdtable.h>
  47 #include <linux/namei.h>
  48 #include <linux/mount.h>
  49 #include <linux/netfilter_ipv4.h>
  50 #include <linux/netfilter_ipv6.h>
  51 #include <linux/tty.h>
  52 #include <net/icmp.h>
  53 #include <net/ip.h>             /* for local_port_range[] */
  54 #include <net/sock.h>
  55 #include <net/tcp.h>            /* struct or_callable used in sock_rcv_skb */
  56 #include <net/net_namespace.h>
  57 #include <net/netlabel.h>
  58 #include <linux/uaccess.h>
  59 #include <asm/ioctls.h>
  60 #include <linux/atomic.h>
  61 #include <linux/bitops.h>
  62 #include <linux/interrupt.h>
  63 #include <linux/netdevice.h>    /* for network interface checks */
  64 #include <net/netlink.h>
  65 #include <linux/tcp.h>
  66 #include <linux/udp.h>
  67 #include <linux/dccp.h>
  68 #include <linux/quota.h>
  69 #include <linux/un.h>           /* for Unix socket types */
  70 #include <net/af_unix.h>        /* for Unix socket types */
  71 #include <linux/parser.h>
  72 #include <linux/nfs_mount.h>
  73 #include <net/ipv6.h>
  74 #include <linux/hugetlb.h>
  75 #include <linux/personality.h>
  76 #include <linux/audit.h>
  77 #include <linux/string.h>
  78 #include <linux/selinux.h>
  79 #include <linux/mutex.h>
  80 #include <linux/posix-timers.h>
  81 #include <linux/syslog.h>
  82 #include <linux/user_namespace.h>
  83 #include <linux/export.h>
  84 #include <linux/security.h>
  85 #include <linux/msg.h>
  86 #include <linux/shm.h>
  87
  88 #include "avc.h"
  89 #include "objsec.h"
  90 #include "netif.h"
  91 #include "netnode.h"
  92 #include "netport.h"
  93 #include "xfrm.h"
  94 #include "netlabel.h"
  95 #include "audit.h"
  96 #include "avc_ss.h"
  97
  98 #define NUM_SEL_MNT_OPTS 5
  99
 100 extern struct security_operations *security_ops;
 101
 102 /* SECMARK reference count */
 103 static atomic_t selinux_secmark_refcount = ATOMIC_INIT(0);
 104
 105 #ifdef CONFIG_SECURITY_SELINUX_DEVELOP
 106 int selinux_enforcing;
 107
 108 static int __init enforcing_setup(char *str)
 109 {
 110         unsigned long enforcing;
 111         if (!strict_strtoul(str, 0, &enforcing))
 112                 selinux_enforcing = enforcing ? 1 : 0;
 113         return 1;
 114 }
 115 __setup("enforcing=", enforcing_setup);
 116 #endif
 117
 118 #ifdef CONFIG_SECURITY_SELINUX_BOOTPARAM
 119 int selinux_enabled = CONFIG_SECURITY_SELINUX_BOOTPARAM_VALUE;
 120
 121 static int __init selinux_enabled_setup(char *str)
 122 {
 123         unsigned long enabled;
 124         if (!strict_strtoul(str, 0, &enabled))
 125                 selinux_enabled = enabled ? 1 : 0;
 126         return 1;
 127 }
 128 __setup("selinux=", selinux_enabled_setup);
 129 #else
 130 int selinux_enabled = 1;
 131 #endif
 132
 133 static struct kmem_cache *sel_inode_cache;
 134
 135 /**
 136  * selinux_secmark_enabled - Check to see if SECMARK is currently enabled
 137  *
 138  * Description:
 139  * This function checks the SECMARK reference counter to see if any SECMARK
 140  * targets are currently configured, if the reference counter is greater than
 141  * zero SECMARK is considered to be enabled.  Returns true (1) if SECMARK is
 142  * enabled, false (0) if SECMARK is disabled.
 143  *
 144  */
 145 static int selinux_secmark_enabled(void)
 146 {
 147         return (atomic_read(&selinux_secmark_refcount) > 0);
 148 }
 149
 150 /*
 151  * initialise the security for the init task
 152  */
 153 static void cred_init_security(void)
 154 {
 155         struct cred *cred = (struct cred *) current->real_cred;
 156         struct task_security_struct *tsec;
 157
 158         tsec = kzalloc(sizeof(struct task_security_struct), GFP_KERNEL);
 159         if (!tsec)
 160                 panic("SELinux:  Failed to initialize initial task.\n");
 161
 162         tsec->osid = tsec->sid = SECINITSID_KERNEL;
 163         cred->security = tsec;
 164 }
 165
 166 /*
 167  * get the security ID of a set of credentials
 168  */
 169 static inline u32 cred_sid(const struct cred *cred)
 170 {
 171         const struct task_security_struct *tsec;
 172
 173         tsec = cred->security;
 174         return tsec->sid;
 175 }
 176
 177 /*
 178  * get the objective security ID of a task
 179  */
 180 static inline u32 task_sid(const struct task_struct *task)
 181 {
 182         u32 sid;
 183
 184         rcu_read_lock();
 185         sid = cred_sid(__task_cred(task));
 186         rcu_read_unlock();
 187         return sid;
 188 }
 189
 190 /*
 191  * get the subjective security ID of the current task
 192  */
 193 static inline u32 current_sid(void)
 194 {
 195         const struct task_security_struct *tsec = current_security();
 196
 197         return tsec->sid;
 198 }
 199
 200 /* Allocate and free functions for each kind of security blob. */
 201
 202 static int inode_alloc_security(struct inode *inode)
 203 {
 204         struct inode_security_struct *isec;
 205         u32 sid = current_sid();
 206
 207         isec = kmem_cache_zalloc(sel_inode_cache, GFP_NOFS);
 208         if (!isec)
 209                 return -ENOMEM;
 210
 211         mutex_init(&isec->lock);
 212         INIT_LIST_HEAD(&isec->list);
 213         isec->inode = inode;
 214         isec->sid = SECINITSID_UNLABELED;
 215         isec->sclass = SECCLASS_FILE;
 216         isec->task_sid = sid;
 217         inode->i_security = isec;
 218
 219         return 0;
 220 }
 221
 222 static void inode_free_security(struct inode *inode)
 223 {
 224         struct inode_security_struct *isec = inode->i_security;
 225         struct superblock_security_struct *sbsec = inode->i_sb->s_security;
 226
 227         spin_lock(&sbsec->isec_lock);
 228         if (!list_empty(&isec->list))
 229                 list_del_init(&isec->list);
 230         spin_unlock(&sbsec->isec_lock);
 231
 232         inode->i_security = NULL;
 233         kmem_cache_free(sel_inode_cache, isec);
 234 }
 235
 236 static int file_alloc_security(struct file *file)
 237 {
 238         struct file_security_struct *fsec;
 239         u32 sid = current_sid();
 240
 241         fsec = kzalloc(sizeof(struct file_security_struct), GFP_KERNEL);
 242         if (!fsec)
 243                 return -ENOMEM;
 244
 245         fsec->sid = sid;
 246         fsec->fown_sid = sid;
 247         file->f_security = fsec;
 248
 249         return 0;
 250 }
 251
 252 static void file_free_security(struct file *file)
 253 {
 254         struct file_security_struct *fsec = file->f_security;
 255         file->f_security = NULL;
 256         kfree(fsec);
 257 }
 258
 259 static int superblock_alloc_security(struct super_block *sb)
 260 {
 261         struct superblock_security_struct *sbsec;
 262
 263         sbsec = kzalloc(sizeof(struct superblock_security_struct), GFP_KERNEL);
 264         if (!sbsec)
 265                 return -ENOMEM;
 266
 267         mutex_init(&sbsec->lock);
 268         INIT_LIST_HEAD(&sbsec->isec_head);
 269         spin_lock_init(&sbsec->isec_lock);
 270         sbsec->sb = sb;
 271         sbsec->sid = SECINITSID_UNLABELED;
 272         sbsec->def_sid = SECINITSID_FILE;
 273         sbsec->mntpoint_sid = SECINITSID_UNLABELED;
 274         sb->s_security = sbsec;
 275
 276         return 0;
 277 }
 278
 279 static void superblock_free_security(struct super_block *sb)
 280 {
 281         struct superblock_security_struct *sbsec = sb->s_security;
 282         sb->s_security = NULL;
 283         kfree(sbsec);
 284 }
 285
 286 /* The file system's label must be initialized prior to use. */
 287
 288 static const char *labeling_behaviors[7] = {
 289         "uses xattr",
 290         "uses transition SIDs",
 291         "uses task SIDs",
 292         "uses genfs_contexts",
 293         "not configured for labeling",
 294         "uses mountpoint labeling",
 295         "uses native labeling",
 296 };
 297
 298 static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dentry);
 299
 300 static inline int inode_doinit(struct inode *inode)
 301 {
 302         return inode_doinit_with_dentry(inode, NULL);
 303 }
 304
 305 enum {
 306         Opt_error = -1,
 307         Opt_context = 1,
 308         Opt_fscontext = 2,
 309         Opt_defcontext = 3,
 310         Opt_rootcontext = 4,
 311         Opt_labelsupport = 5,
 312 };
 313
 314 static const match_table_t tokens = {
 315         {Opt_context, CONTEXT_STR "%s"},
 316         {Opt_fscontext, FSCONTEXT_STR "%s"},
 317         {Opt_defcontext, DEFCONTEXT_STR "%s"},
 318         {Opt_rootcontext, ROOTCONTEXT_STR "%s"},
 319         {Opt_labelsupport, LABELSUPP_STR},
 320         {Opt_error, NULL},
 321 };
 322
 323 #define SEL_MOUNT_FAIL_MSG "SELinux:  duplicate or incompatible mount options\n"
 324
 325 static int may_context_mount_sb_relabel(u32 sid,
 326                         struct superblock_security_struct *sbsec,
 327                         const struct cred *cred)
 328 {
 329         const struct task_security_struct *tsec = cred->security;
 330         int rc;
 331
 332         rc = avc_has_perm(tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM,
 333                           FILESYSTEM__RELABELFROM, NULL);
 334         if (rc)
 335                 return rc;
 336
 337         rc = avc_has_perm(tsec->sid, sid, SECCLASS_FILESYSTEM,
 338                           FILESYSTEM__RELABELTO, NULL);
 339         return rc;
 340 }
 341
 342 static int may_context_mount_inode_relabel(u32 sid,
 343                         struct superblock_security_struct *sbsec,
 344                         const struct cred *cred)
 345 {
 346         const struct task_security_struct *tsec = cred->security;
 347         int rc;
 348         rc = avc_has_perm(tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM,
 349                           FILESYSTEM__RELABELFROM, NULL);
 350         if (rc)
 351                 return rc;
 352
 353         rc = avc_has_perm(sid, sbsec->sid, SECCLASS_FILESYSTEM,
 354                           FILESYSTEM__ASSOCIATE, NULL);
 355         return rc;
 356 }
 357
 358 static int sb_finish_set_opts(struct super_block *sb)
 359 {
 360         struct superblock_security_struct *sbsec = sb->s_security;
 361         struct dentry *root = sb->s_root;
 362         struct inode *root_inode = root->d_inode;
 363         int rc = 0;
 364
 365         if (sbsec->behavior == SECURITY_FS_USE_XATTR) {
 366                 /* Make sure that the xattr handler exists and that no
 367                    error other than -ENODATA is returned by getxattr on
 368                    the root directory.  -ENODATA is ok, as this may be
 369                    the first boot of the SELinux kernel before we have
 370                    assigned xattr values to the filesystem. */
 371                 if (!root_inode->i_op->getxattr) {
 372                         printk(KERN_WARNING "SELinux: (dev %s, type %s) has no "
 373                                "xattr support\n", sb->s_id, sb->s_type->name);
 374                         rc = -EOPNOTSUPP;
 375                         goto out;
 376                 }
 377                 rc = root_inode->i_op->getxattr(root, XATTR_NAME_SELINUX, NULL, 0);
 378                 if (rc < 0 && rc != -ENODATA) {
 379                         if (rc == -EOPNOTSUPP)
 380                                 printk(KERN_WARNING "SELinux: (dev %s, type "
 381                                        "%s) has no security xattr handler\n",
 382                                        sb->s_id, sb->s_type->name);
 383                         else
 384                                 printk(KERN_WARNING "SELinux: (dev %s, type "
 385                                        "%s) getxattr errno %d\n", sb->s_id,
 386                                        sb->s_type->name, -rc);
 387                         goto out;
 388                 }
 389         }
 390
 391         sbsec->flags |= (SE_SBINITIALIZED | SE_SBLABELSUPP);
 392
 393         if (sbsec->behavior > ARRAY_SIZE(labeling_behaviors))
 394                 printk(KERN_ERR "SELinux: initialized (dev %s, type %s), unknown behavior\n",
 395                        sb->s_id, sb->s_type->name);
 396         else
 397                 printk(KERN_DEBUG "SELinux: initialized (dev %s, type %s), %s\n",
 398                        sb->s_id, sb->s_type->name,
 399                        labeling_behaviors[sbsec->behavior-1]);
 400
 401         if (sbsec->behavior == SECURITY_FS_USE_GENFS ||
 402             sbsec->behavior == SECURITY_FS_USE_MNTPOINT ||
 403             sbsec->behavior == SECURITY_FS_USE_NONE ||
 404             sbsec->behavior > ARRAY_SIZE(labeling_behaviors))
 405                 sbsec->flags &= ~SE_SBLABELSUPP;
 406
 407         /* Special handling for sysfs. Is genfs but also has setxattr handler*/
 408         if (strncmp(sb->s_type->name, "sysfs", sizeof("sysfs")) == 0)
 409                 sbsec->flags |= SE_SBLABELSUPP;
 410
 411         /* Initialize the root inode. */
 412         rc = inode_doinit_with_dentry(root_inode, root);
 413
 414         /* Initialize any other inodes associated with the superblock, e.g.
 415            inodes created prior to initial policy load or inodes created
 416            during get_sb by a pseudo filesystem that directly
 417            populates itself. */
 418         spin_lock(&sbsec->isec_lock);
 419 next_inode:
 420         if (!list_empty(&sbsec->isec_head)) {
 421                 struct inode_security_struct *isec =
 422                                 list_entry(sbsec->isec_head.next,
 423                                            struct inode_security_struct, list);
 424                 struct inode *inode = isec->inode;
 425                 spin_unlock(&sbsec->isec_lock);
 426                 inode = igrab(inode);
 427                 if (inode) {
 428                         if (!IS_PRIVATE(inode))
 429                                 inode_doinit(inode);
 430                         iput(inode);
 431                 }
 432                 spin_lock(&sbsec->isec_lock);
 433                 list_del_init(&isec->list);
 434                 goto next_inode;
 435         }
 436         spin_unlock(&sbsec->isec_lock);
 437 out:
 438         return rc;
 439 }
 440
 441 /*
 442  * This function should allow an FS to ask what it's mount security
 443  * options were so it can use those later for submounts, displaying
 444  * mount options, or whatever.
 445  */
 446 static int selinux_get_mnt_opts(const struct super_block *sb,
 447                                 struct security_mnt_opts *opts)
 448 {
 449         int rc = 0, i;
 450         struct superblock_security_struct *sbsec = sb->s_security;
 451         char *context = NULL;
 452         u32 len;
 453         char tmp;
 454
 455         security_init_mnt_opts(opts);
 456
 457         if (!(sbsec->flags & SE_SBINITIALIZED))
 458                 return -EINVAL;
 459
 460         if (!ss_initialized)
 461                 return -EINVAL;
 462
 463         tmp = sbsec->flags & SE_MNTMASK;
 464         /* count the number of mount options for this sb */
 465         for (i = 0; i < 8; i++) {
 466                 if (tmp & 0x01)
 467                         opts->num_mnt_opts++;
 468                 tmp >>= 1;
 469         }
 470         /* Check if the Label support flag is set */
 471         if (sbsec->flags & SE_SBLABELSUPP)
 472                 opts->num_mnt_opts++;
 473
 474         opts->mnt_opts = kcalloc(opts->num_mnt_opts, sizeof(char *), GFP_ATOMIC);
 475         if (!opts->mnt_opts) {
 476                 rc = -ENOMEM;
 477                 goto out_free;
 478         }
 479
 480         opts->mnt_opts_flags = kcalloc(opts->num_mnt_opts, sizeof(int), GFP_ATOMIC);
 481         if (!opts->mnt_opts_flags) {
 482                 rc = -ENOMEM;
 483                 goto out_free;
 484         }
 485
 486         i = 0;
 487         if (sbsec->flags & FSCONTEXT_MNT) {
 488                 rc = security_sid_to_context(sbsec->sid, &context, &len);
 489                 if (rc)
 490                         goto out_free;
 491                 opts->mnt_opts[i] = context;
 492                 opts->mnt_opts_flags[i++] = FSCONTEXT_MNT;
 493         }
 494         if (sbsec->flags & CONTEXT_MNT) {
 495                 rc = security_sid_to_context(sbsec->mntpoint_sid, &context, &len);
 496                 if (rc)
 497                         goto out_free;
 498                 opts->mnt_opts[i] = context;
 499                 opts->mnt_opts_flags[i++] = CONTEXT_MNT;
 500         }
 501         if (sbsec->flags & DEFCONTEXT_MNT) {
 502                 rc = security_sid_to_context(sbsec->def_sid, &context, &len);
 503                 if (rc)
 504                         goto out_free;
 505                 opts->mnt_opts[i] = context;
 506                 opts->mnt_opts_flags[i++] = DEFCONTEXT_MNT;
 507         }
 508         if (sbsec->flags & ROOTCONTEXT_MNT) {
 509                 struct inode *root = sbsec->sb->s_root->d_inode;
 510                 struct inode_security_struct *isec = root->i_security;
 511
 512                 rc = security_sid_to_context(isec->sid, &context, &len);
 513                 if (rc)
 514                         goto out_free;
 515                 opts->mnt_opts[i] = context;
 516                 opts->mnt_opts_flags[i++] = ROOTCONTEXT_MNT;
 517         }
 518         if (sbsec->flags & SE_SBLABELSUPP) {
 519                 opts->mnt_opts[i] = NULL;
 520                 opts->mnt_opts_flags[i++] = SE_SBLABELSUPP;
 521         }
 522
 523         BUG_ON(i != opts->num_mnt_opts);
 524
 525         return 0;
 526
 527 out_free:
 528         security_free_mnt_opts(opts);
 529         return rc;
 530 }
 531
 532 static int bad_option(struct superblock_security_struct *sbsec, char flag,
 533                       u32 old_sid, u32 new_sid)
 534 {
 535         char mnt_flags = sbsec->flags & SE_MNTMASK;
 536
 537         /* check if the old mount command had the same options */
 538         if (sbsec->flags & SE_SBINITIALIZED)
 539                 if (!(sbsec->flags & flag) ||
 540                     (old_sid != new_sid))
 541                         return 1;
 542
 543         /* check if we were passed the same options twice,
 544          * aka someone passed context=a,context=b
 545          */
 546         if (!(sbsec->flags & SE_SBINITIALIZED))
 547                 if (mnt_flags & flag)
 548                         return 1;
 549         return 0;
 550 }
 551
 552 /*
 553  * Allow filesystems with binary mount data to explicitly set mount point
 554  * labeling information.
 555  */
 556 static int selinux_set_mnt_opts(struct super_block *sb,
 557                                 struct security_mnt_opts *opts,
 558                                 unsigned long kern_flags,
 559                                 unsigned long *set_kern_flags)
 560 {
 561         const struct cred *cred = current_cred();
 562         int rc = 0, i;
 563         struct superblock_security_struct *sbsec = sb->s_security;
 564         const char *name = sb->s_type->name;
 565         struct inode *inode = sbsec->sb->s_root->d_inode;
 566         struct inode_security_struct *root_isec = inode->i_security;
 567         u32 fscontext_sid = 0, context_sid = 0, rootcontext_sid = 0;
 568         u32 defcontext_sid = 0;
 569         char **mount_options = opts->mnt_opts;
 570         int *flags = opts->mnt_opts_flags;
 571         int num_opts = opts->num_mnt_opts;
 572
 573         mutex_lock(&sbsec->lock);
 574
 575         if (!ss_initialized) {
 576                 if (!num_opts) {
 577                         /* Defer initialization until selinux_complete_init,
 578                            after the initial policy is loaded and the security
 579                            server is ready to handle calls. */
 580                         goto out;
 581                 }
 582                 rc = -EINVAL;
 583                 printk(KERN_WARNING "SELinux: Unable to set superblock options "
 584                         "before the security server is initialized\n");
 585                 goto out;
 586         }
 587         if (kern_flags && !set_kern_flags) {
 588                 /* Specifying internal flags without providing a place to
 589                  * place the results is not allowed */
 590                 rc = -EINVAL;
 591                 goto out;
 592         }
 593
 594         /*
 595          * Binary mount data FS will come through this function twice.  Once
 596          * from an explicit call and once from the generic calls from the vfs.
 597          * Since the generic VFS calls will not contain any security mount data
 598          * we need to skip the double mount verification.
 599          *
 600          * This does open a hole in which we will not notice if the first
 601          * mount using this sb set explict options and a second mount using
 602          * this sb does not set any security options.  (The first options
 603          * will be used for both mounts)
 604          */
 605         if ((sbsec->flags & SE_SBINITIALIZED) && (sb->s_type->fs_flags & FS_BINARY_MOUNTDATA)
 606             && (num_opts == 0))
 607                 goto out;
 608
 609         /*
 610          * parse the mount options, check if they are valid sids.
 611          * also check if someone is trying to mount the same sb more
 612          * than once with different security options.
 613          */
 614         for (i = 0; i < num_opts; i++) {
 615                 u32 sid;
 616
 617                 if (flags[i] == SE_SBLABELSUPP)
 618                         continue;
 619                 rc = security_context_to_sid(mount_options[i],
 620                                              strlen(mount_options[i]), &sid);
 621                 if (rc) {
 622                         printk(KERN_WARNING "SELinux: security_context_to_sid"
 623                                "(%s) failed for (dev %s, type %s) errno=%d\n",
 624                                mount_options[i], sb->s_id, name, rc);
 625                         goto out;
 626                 }
 627                 switch (flags[i]) {
 628                 case FSCONTEXT_MNT:
 629                         fscontext_sid = sid;
 630
 631                         if (bad_option(sbsec, FSCONTEXT_MNT, sbsec->sid,
 632                                         fscontext_sid))
 633                                 goto out_double_mount;
 634
 635                         sbsec->flags |= FSCONTEXT_MNT;
 636                         break;
 637                 case CONTEXT_MNT:
 638                         context_sid = sid;
 639
 640                         if (bad_option(sbsec, CONTEXT_MNT, sbsec->mntpoint_sid,
 641                                         context_sid))
 642                                 goto out_double_mount;
 643
 644                         sbsec->flags |= CONTEXT_MNT;
 645                         break;
 646                 case ROOTCONTEXT_MNT:
 647                         rootcontext_sid = sid;
 648
 649                         if (bad_option(sbsec, ROOTCONTEXT_MNT, root_isec->sid,
 650                                         rootcontext_sid))
 651                                 goto out_double_mount;
 652
 653                         sbsec->flags |= ROOTCONTEXT_MNT;
 654
 655                         break;
 656                 case DEFCONTEXT_MNT:
 657                         defcontext_sid = sid;
 658
 659                         if (bad_option(sbsec, DEFCONTEXT_MNT, sbsec->def_sid,
 660                                         defcontext_sid))
 661                                 goto out_double_mount;
 662
 663                         sbsec->flags |= DEFCONTEXT_MNT;
 664
 665                         break;
 666                 default:
 667                         rc = -EINVAL;
 668                         goto out;
 669                 }
 670         }
 671
 672         if (sbsec->flags & SE_SBINITIALIZED) {
 673                 /* previously mounted with options, but not on this attempt? */
 674                 if ((sbsec->flags & SE_MNTMASK) && !num_opts)
 675                         goto out_double_mount;
 676                 rc = 0;
 677                 goto out;
 678         }
 679
 680         if (strcmp(sb->s_type->name, "proc") == 0)
 681                 sbsec->flags |= SE_SBPROC;
 682
 683         if (!sbsec->behavior) {
 684                 /*
 685                  * Determine the labeling behavior to use for this
 686                  * filesystem type.
 687                  */
 688                 rc = security_fs_use((sbsec->flags & SE_SBPROC) ?
 689                                         "proc" : sb->s_type->name,
 690                                         &sbsec->behavior, &sbsec->sid);
 691                 if (rc) {
 692                         printk(KERN_WARNING
 693                                 "%s: security_fs_use(%s) returned %d\n",
 694                                         __func__, sb->s_type->name, rc);
 695                         goto out;
 696                 }
 697         }
 698         /* sets the context of the superblock for the fs being mounted. */
 699         if (fscontext_sid) {
 700                 rc = may_context_mount_sb_relabel(fscontext_sid, sbsec, cred);
 701                 if (rc)
 702                         goto out;
 703
 704                 sbsec->sid = fscontext_sid;
 705         }
 706
 707         /*
 708          * Switch to using mount point labeling behavior.
 709          * sets the label used on all file below the mountpoint, and will set
 710          * the superblock context if not already set.
 711          */
 712         if (kern_flags & SECURITY_LSM_NATIVE_LABELS && !context_sid) {
 713                 sbsec->behavior = SECURITY_FS_USE_NATIVE;
 714                 *set_kern_flags |= SECURITY_LSM_NATIVE_LABELS;
 715         }
 716
 717         if (context_sid) {
 718                 if (!fscontext_sid) {
 719                         rc = may_context_mount_sb_relabel(context_sid, sbsec,
 720                                                           cred);
 721                         if (rc)
 722                                 goto out;
 723                         sbsec->sid = context_sid;
 724                 } else {
 725                         rc = may_context_mount_inode_relabel(context_sid, sbsec,
 726                                                              cred);
 727                         if (rc)
 728                                 goto out;
 729                 }
 730                 if (!rootcontext_sid)
 731                         rootcontext_sid = context_sid;
 732
 733                 sbsec->mntpoint_sid = context_sid;
 734                 sbsec->behavior = SECURITY_FS_USE_MNTPOINT;
 735         }
 736
 737         if (rootcontext_sid) {
 738                 rc = may_context_mount_inode_relabel(rootcontext_sid, sbsec,
 739                                                      cred);
 740                 if (rc)
 741                         goto out;
 742
 743                 root_isec->sid = rootcontext_sid;
 744                 root_isec->initialized = 1;
 745         }
 746
 747         if (defcontext_sid) {
 748                 if (sbsec->behavior != SECURITY_FS_USE_XATTR &&
 749                         sbsec->behavior != SECURITY_FS_USE_NATIVE) {
 750                         rc = -EINVAL;
 751                         printk(KERN_WARNING "SELinux: defcontext option is "
 752                                "invalid for this filesystem type\n");
 753                         goto out;
 754                 }
 755
 756                 if (defcontext_sid != sbsec->def_sid) {
 757                         rc = may_context_mount_inode_relabel(defcontext_sid,
 758                                                              sbsec, cred);
 759                         if (rc)
 760                                 goto out;
 761                 }
 762
 763                 sbsec->def_sid = defcontext_sid;
 764         }
 765
 766         rc = sb_finish_set_opts(sb);
 767 out:
 768         mutex_unlock(&sbsec->lock);
 769         return rc;
 770 out_double_mount:
 771         rc = -EINVAL;
 772         printk(KERN_WARNING "SELinux: mount invalid.  Same superblock, different "
 773                "security settings for (dev %s, type %s)\n", sb->s_id, name);
 774         goto out;
 775 }
 776
 777 static int selinux_cmp_sb_context(const struct super_block *oldsb,
 778                                     const struct super_block *newsb)
 779 {
 780         struct superblock_security_struct *old = oldsb->s_security;
 781         struct superblock_security_struct *new = newsb->s_security;
 782         char oldflags = old->flags & SE_MNTMASK;
 783         char newflags = new->flags & SE_MNTMASK;
 784
 785         if (oldflags != newflags)
 786                 goto mismatch;
 787         if ((oldflags & FSCONTEXT_MNT) && old->sid != new->sid)
 788                 goto mismatch;
 789         if ((oldflags & CONTEXT_MNT) && old->mntpoint_sid != new->mntpoint_sid)
 790                 goto mismatch;
 791         if ((oldflags & DEFCONTEXT_MNT) && old->def_sid != new->def_sid)
 792                 goto mismatch;
 793         if (oldflags & ROOTCONTEXT_MNT) {
 794                 struct inode_security_struct *oldroot = oldsb->s_root->d_inode->i_security;
 795                 struct inode_security_struct *newroot = newsb->s_root->d_inode->i_security;
 796                 if (oldroot->sid != newroot->sid)
 797                         goto mismatch;
 798         }
 799         return 0;
 800 mismatch:
 801         printk(KERN_WARNING "SELinux: mount invalid.  Same superblock, "
 802                             "different security settings for (dev %s, "
 803                             "type %s)\n", newsb->s_id, newsb->s_type->name);
 804         return -EBUSY;
 805 }
 806
 807 static int selinux_sb_clone_mnt_opts(const struct super_block *oldsb,
 808                                         struct super_block *newsb)
 809 {
 810         const struct superblock_security_struct *oldsbsec = oldsb->s_security;
 811         struct superblock_security_struct *newsbsec = newsb->s_security;
 812
 813         int set_fscontext =     (oldsbsec->flags & FSCONTEXT_MNT);
 814         int set_context =       (oldsbsec->flags & CONTEXT_MNT);
 815         int set_rootcontext =   (oldsbsec->flags & ROOTCONTEXT_MNT);
 816
 817         /*
 818          * if the parent was able to be mounted it clearly had no special lsm
 819          * mount options.  thus we can safely deal with this superblock later
 820          */
 821         if (!ss_initialized)
 822                 return 0;
 823
 824         /* how can we clone if the old one wasn't set up?? */
 825         BUG_ON(!(oldsbsec->flags & SE_SBINITIALIZED));
 826
 827         /* if fs is reusing a sb, make sure that the contexts match */
 828         if (newsbsec->flags & SE_SBINITIALIZED)
 829                 return selinux_cmp_sb_context(oldsb, newsb);
 830
 831         mutex_lock(&newsbsec->lock);
 832
 833         newsbsec->flags = oldsbsec->flags;
 834
 835         newsbsec->sid = oldsbsec->sid;
 836         newsbsec->def_sid = oldsbsec->def_sid;
 837         newsbsec->behavior = oldsbsec->behavior;
 838
 839         if (set_context) {
 840                 u32 sid = oldsbsec->mntpoint_sid;
 841
 842                 if (!set_fscontext)
 843                         newsbsec->sid = sid;
 844                 if (!set_rootcontext) {
 845                         struct inode *newinode = newsb->s_root->d_inode;
 846                         struct inode_security_struct *newisec = newinode->i_security;
 847                         newisec->sid = sid;
 848                 }
 849                 newsbsec->mntpoint_sid = sid;
 850         }
 851         if (set_rootcontext) {
 852                 const struct inode *oldinode = oldsb->s_root->d_inode;
 853                 const struct inode_security_struct *oldisec = oldinode->i_security;
 854                 struct inode *newinode = newsb->s_root->d_inode;
 855                 struct inode_security_struct *newisec = newinode->i_security;
 856
 857                 newisec->sid = oldisec->sid;
 858         }
 859
 860         sb_finish_set_opts(newsb);
 861         mutex_unlock(&newsbsec->lock);
 862         return 0;
 863 }
 864
 865 static int selinux_parse_opts_str(char *options,
 866                                   struct security_mnt_opts *opts)
 867 {
 868         char *p;
 869         char *context = NULL, *defcontext = NULL;
 870         char *fscontext = NULL, *rootcontext = NULL;
 871         int rc, num_mnt_opts = 0;
 872
 873         opts->num_mnt_opts = 0;
 874
 875         /* Standard string-based options. */
 876         while ((p = strsep(&options, "|")) != NULL) {
 877                 int token;
 878                 substring_t args[MAX_OPT_ARGS];
 879
 880                 if (!*p)
 881                         continue;
 882
 883                 token = match_token(p, tokens, args);
 884
 885                 switch (token) {
 886                 case Opt_context:
 887                         if (context || defcontext) {
 888                                 rc = -EINVAL;
 889                                 printk(KERN_WARNING SEL_MOUNT_FAIL_MSG);
 890                                 goto out_err;
 891                         }
 892                         context = match_strdup(&args[0]);
 893                         if (!context) {
 894                                 rc = -ENOMEM;
 895                                 goto out_err;
 896                         }
 897                         break;
 898
 899                 case Opt_fscontext:
 900                         if (fscontext) {
 901                                 rc = -EINVAL;
 902                                 printk(KERN_WARNING SEL_MOUNT_FAIL_MSG);
 903                                 goto out_err;
 904                         }
 905                         fscontext = match_strdup(&args[0]);
 906                         if (!fscontext) {
 907                                 rc = -ENOMEM;
 908                                 goto out_err;
 909                         }
 910                         break;
 911
 912                 case Opt_rootcontext:
 913                         if (rootcontext) {
 914                                 rc = -EINVAL;
 915                                 printk(KERN_WARNING SEL_MOUNT_FAIL_MSG);
 916                                 goto out_err;
 917                         }
 918                         rootcontext = match_strdup(&args[0]);
 919                         if (!rootcontext) {
 920                                 rc = -ENOMEM;
 921                                 goto out_err;
 922                         }
 923                         break;
 924
 925                 case Opt_defcontext:
 926                         if (context || defcontext) {
 927                                 rc = -EINVAL;
 928                                 printk(KERN_WARNING SEL_MOUNT_FAIL_MSG);
 929                                 goto out_err;
 930                         }
 931                         defcontext = match_strdup(&args[0]);
 932                         if (!defcontext) {
 933                                 rc = -ENOMEM;
 934                                 goto out_err;
 935                         }
 936                         break;
 937                 case Opt_labelsupport:
 938                         break;
 939                 default:
 940                         rc = -EINVAL;
 941                         printk(KERN_WARNING "SELinux:  unknown mount option\n");
 942                         goto out_err;
 943
 944                 }
 945         }
 946
 947         rc = -ENOMEM;
 948         opts->mnt_opts = kcalloc(NUM_SEL_MNT_OPTS, sizeof(char *), GFP_ATOMIC);
 949         if (!opts->mnt_opts)
 950                 goto out_err;
 951
 952         opts->mnt_opts_flags = kcalloc(NUM_SEL_MNT_OPTS, sizeof(int), GFP_ATOMIC);
 953         if (!opts->mnt_opts_flags) {
 954                 kfree(opts->mnt_opts);
 955                 goto out_err;
 956         }
 957
 958         if (fscontext) {
 959                 opts->mnt_opts[num_mnt_opts] = fscontext;
 960                 opts->mnt_opts_flags[num_mnt_opts++] = FSCONTEXT_MNT;
 961         }
 962         if (context) {
 963                 opts->mnt_opts[num_mnt_opts] = context;
 964                 opts->mnt_opts_flags[num_mnt_opts++] = CONTEXT_MNT;
 965         }
 966         if (rootcontext) {
 967                 opts->mnt_opts[num_mnt_opts] = rootcontext;
 968                 opts->mnt_opts_flags[num_mnt_opts++] = ROOTCONTEXT_MNT;
 969         }
 970         if (defcontext) {
 971                 opts->mnt_opts[num_mnt_opts] = defcontext;
 972                 opts->mnt_opts_flags[num_mnt_opts++] = DEFCONTEXT_MNT;
 973         }
 974
 975         opts->num_mnt_opts = num_mnt_opts;
 976         return 0;
 977
 978 out_err:
 979         kfree(context);
 980         kfree(defcontext);
 981         kfree(fscontext);
 982         kfree(rootcontext);
 983         return rc;
 984 }
 985 /*
 986  * string mount options parsing and call set the sbsec
 987  */
 988 static int superblock_doinit(struct super_block *sb, void *data)
 989 {
 990         int rc = 0;
 991         char *options = data;
 992         struct security_mnt_opts opts;
 993
 994         security_init_mnt_opts(&opts);
 995
 996         if (!data)
 997                 goto out;
 998
 999         BUG_ON(sb->s_type->fs_flags & FS_BINARY_MOUNTDATA);
1000
1001         rc = selinux_parse_opts_str(options, &opts);
1002         if (rc)
1003                 goto out_err;
1004
1005 out:
1006         rc = selinux_set_mnt_opts(sb, &opts, 0, NULL);
1007
1008 out_err:
1009         security_free_mnt_opts(&opts);
1010         return rc;
1011 }
1012
1013 static void selinux_write_opts(struct seq_file *m,
1014                                struct security_mnt_opts *opts)
1015 {
1016         int i;
1017         char *prefix;
1018
1019         for (i = 0; i < opts->num_mnt_opts; i++) {
1020                 char *has_comma;
1021
1022                 if (opts->mnt_opts[i])
1023                         has_comma = strchr(opts->mnt_opts[i], ',');
1024                 else
1025                         has_comma = NULL;
1026
1027                 switch (opts->mnt_opts_flags[i]) {
1028                 case CONTEXT_MNT:
1029                         prefix = CONTEXT_STR;
1030                         break;
1031                 case FSCONTEXT_MNT:
1032                         prefix = FSCONTEXT_STR;
1033                         break;
1034                 case ROOTCONTEXT_MNT:
1035                         prefix = ROOTCONTEXT_STR;
1036                         break;
1037                 case DEFCONTEXT_MNT:
1038                         prefix = DEFCONTEXT_STR;
1039                         break;
1040                 case SE_SBLABELSUPP:
1041                         seq_putc(m, ',');
1042                         seq_puts(m, LABELSUPP_STR);
1043                         continue;
1044                 default:
1045                         BUG();
1046                         return;
1047                 };
1048                 /* we need a comma before each option */
1049                 seq_putc(m, ',');
1050                 seq_puts(m, prefix);
1051                 if (has_comma)
1052                         seq_putc(m, '\"');
1053                 seq_puts(m, opts->mnt_opts[i]);
1054                 if (has_comma)
1055                         seq_putc(m, '\"');
1056         }
1057 }
1058
1059 static int selinux_sb_show_options(struct seq_file *m, struct super_block *sb)
1060 {
1061         struct security_mnt_opts opts;
1062         int rc;
1063
1064         rc = selinux_get_mnt_opts(sb, &opts);
1065         if (rc) {
1066                 /* before policy load we may get EINVAL, don't show anything */
1067                 if (rc == -EINVAL)
1068                         rc = 0;
1069                 return rc;
1070         }
1071
1072         selinux_write_opts(m, &opts);
1073
1074         security_free_mnt_opts(&opts);
1075
1076         return rc;
1077 }
1078
1079 static inline u16 inode_mode_to_security_class(umode_t mode)
1080 {
1081         switch (mode & S_IFMT) {
1082         case S_IFSOCK:
1083                 return SECCLASS_SOCK_FILE;
1084         case S_IFLNK:
1085                 return SECCLASS_LNK_FILE;
1086         case S_IFREG:
1087                 return SECCLASS_FILE;
1088         case S_IFBLK:
1089                 return SECCLASS_BLK_FILE;
1090         case S_IFDIR:
1091                 return SECCLASS_DIR;
1092         case S_IFCHR:
1093                 return SECCLASS_CHR_FILE;
1094         case S_IFIFO:
1095                 return SECCLASS_FIFO_FILE;
1096
1097         }
1098
1099         return SECCLASS_FILE;
1100 }
1101
1102 static inline int default_protocol_stream(int protocol)
1103 {
1104         return (protocol == IPPROTO_IP || protocol == IPPROTO_TCP);
1105 }
1106
1107 static inline int default_protocol_dgram(int protocol)
1108 {
1109         return (protocol == IPPROTO_IP || protocol == IPPROTO_UDP);
1110 }
1111
1112 static inline u16 socket_type_to_security_class(int family, int type, int protocol)
1113 {
1114         switch (family) {
1115         case PF_UNIX:
1116                 switch (type) {
1117                 case SOCK_STREAM:
1118                 case SOCK_SEQPACKET:
1119                         return SECCLASS_UNIX_STREAM_SOCKET;
1120                 case SOCK_DGRAM:
1121                         return SECCLASS_UNIX_DGRAM_SOCKET;
1122                 }
1123                 break;
1124         case PF_INET:
1125         case PF_INET6:
1126                 switch (type) {
1127                 case SOCK_STREAM:
1128                         if (default_protocol_stream(protocol))
1129                                 return SECCLASS_TCP_SOCKET;
1130                         else
1131                                 return SECCLASS_RAWIP_SOCKET;
1132                 case SOCK_DGRAM:
1133                         if (default_protocol_dgram(protocol))
1134                                 return SECCLASS_UDP_SOCKET;
1135                         else
1136                                 return SECCLASS_RAWIP_SOCKET;
1137                 case SOCK_DCCP:
1138                         return SECCLASS_DCCP_SOCKET;
1139                 default:
1140                         return SECCLASS_RAWIP_SOCKET;
1141                 }
1142                 break;
1143         case PF_NETLINK:
1144                 switch (protocol) {
1145                 case NETLINK_ROUTE:
1146                         return SECCLASS_NETLINK_ROUTE_SOCKET;
1147                 case NETLINK_FIREWALL:
1148                         return SECCLASS_NETLINK_FIREWALL_SOCKET;
1149                 case NETLINK_SOCK_DIAG:
1150                         return SECCLASS_NETLINK_TCPDIAG_SOCKET;
1151                 case NETLINK_NFLOG:
1152                         return SECCLASS_NETLINK_NFLOG_SOCKET;
1153                 case NETLINK_XFRM:
1154                         return SECCLASS_NETLINK_XFRM_SOCKET;
1155                 case NETLINK_SELINUX:
1156                         return SECCLASS_NETLINK_SELINUX_SOCKET;
1157                 case NETLINK_AUDIT:
1158                         return SECCLASS_NETLINK_AUDIT_SOCKET;
1159                 case NETLINK_IP6_FW:
1160                         return SECCLASS_NETLINK_IP6FW_SOCKET;
1161                 case NETLINK_DNRTMSG:
1162                         return SECCLASS_NETLINK_DNRT_SOCKET;
1163                 case NETLINK_KOBJECT_UEVENT:
1164                         return SECCLASS_NETLINK_KOBJECT_UEVENT_SOCKET;
1165                 default:
1166                         return SECCLASS_NETLINK_SOCKET;
1167                 }
1168         case PF_PACKET:
1169                 return SECCLASS_PACKET_SOCKET;
1170         case PF_KEY:
1171                 return SECCLASS_KEY_SOCKET;
1172         case PF_APPLETALK:
1173                 return SECCLASS_APPLETALK_SOCKET;
1174         }
1175
1176         return SECCLASS_SOCKET;
1177 }
1178
1179 #ifdef CONFIG_PROC_FS
1180 static int selinux_proc_get_sid(struct dentry *dentry,
1181                                 u16 tclass,
1182                                 u32 *sid)
1183 {
1184         int rc;
1185         char *buffer, *path;
1186
1187         buffer = (char *)__get_free_page(GFP_KERNEL);
1188         if (!buffer)
1189                 return -ENOMEM;
1190
1191         path = dentry_path_raw(dentry, buffer, PAGE_SIZE);
1192         if (IS_ERR(path))
1193                 rc = PTR_ERR(path);
1194         else {
1195                 /* each process gets a /proc/PID/ entry. Strip off the
1196                  * PID part to get a valid selinux labeling.
1197                  * e.g. /proc/1/net/rpc/nfs -> /net/rpc/nfs */
1198                 while (path[1] >= '0' && path[1] <= '9') {
1199                         path[1] = '/';
1200                         path++;
1201                 }
1202                 rc = security_genfs_sid("proc", path, tclass, sid);
1203         }
1204         free_page((unsigned long)buffer);
1205         return rc;
1206 }
1207 #else
1208 static int selinux_proc_get_sid(struct dentry *dentry,
1209                                 u16 tclass,
1210                                 u32 *sid)
1211 {
1212         return -EINVAL;
1213 }
1214 #endif
1215
1216 /* The inode's security attributes must be initialized before first use. */
1217 static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dentry)
1218 {
1219         struct superblock_security_struct *sbsec = NULL;
1220         struct inode_security_struct *isec = inode->i_security;
1221         u32 sid;
1222         struct dentry *dentry;
1223 #define INITCONTEXTLEN 255
1224         char *context = NULL;
1225         unsigned len = 0;
1226         int rc = 0;
1227
1228         if (isec->initialized)
1229                 goto out;
1230
1231         mutex_lock(&isec->lock);
1232         if (isec->initialized)
1233                 goto out_unlock;
1234
1235         sbsec = inode->i_sb->s_security;
1236         if (!(sbsec->flags & SE_SBINITIALIZED)) {
1237                 /* Defer initialization until selinux_complete_init,
1238                    after the initial policy is loaded and the security
1239                    server is ready to handle calls. */
1240                 spin_lock(&sbsec->isec_lock);
1241                 if (list_empty(&isec->list))
1242                         list_add(&isec->list, &sbsec->isec_head);
1243                 spin_unlock(&sbsec->isec_lock);
1244                 goto out_unlock;
1245         }
1246
1247         switch (sbsec->behavior) {
1248         case SECURITY_FS_USE_NATIVE:
1249                 break;
1250         case SECURITY_FS_USE_XATTR:
1251                 if (!inode->i_op->getxattr) {
1252                         isec->sid = sbsec->def_sid;
1253                         break;
1254                 }
1255
1256                 /* Need a dentry, since the xattr API requires one.
1257                    Life would be simpler if we could just pass the inode. */
1258                 if (opt_dentry) {
1259                         /* Called from d_instantiate or d_splice_alias. */
1260                         dentry = dget(opt_dentry);
1261                 } else {
1262                         /* Called from selinux_complete_init, try to find a dentry. */
1263                         dentry = d_find_alias(inode);
1264                 }
1265                 if (!dentry) {
1266                         /*
1267                          * this is can be hit on boot when a file is accessed
1268                          * before the policy is loaded.  When we load policy we
1269                          * may find inodes that have no dentry on the
1270                          * sbsec->isec_head list.  No reason to complain as these
1271                          * will get fixed up the next time we go through
1272                          * inode_doinit with a dentry, before these inodes could
1273                          * be used again by userspace.
1274                          */
1275                         goto out_unlock;
1276                 }
1277
1278                 len = INITCONTEXTLEN;
1279                 context = kmalloc(len+1, GFP_NOFS);
1280                 if (!context) {
1281                         rc = -ENOMEM;
1282                         dput(dentry);
1283                         goto out_unlock;
1284                 }
1285                 context[len] = '\0';
1286                 rc = inode->i_op->getxattr(dentry, XATTR_NAME_SELINUX,
1287                                            context, len);
1288                 if (rc == -ERANGE) {
1289                         kfree(context);
1290
1291                         /* Need a larger buffer.  Query for the right size. */
1292                         rc = inode->i_op->getxattr(dentry, XATTR_NAME_SELINUX,
1293                                                    NULL, 0);
1294                         if (rc < 0) {
1295                                 dput(dentry);
1296                                 goto out_unlock;
1297                         }
1298                         len = rc;
1299                         context = kmalloc(len+1, GFP_NOFS);
1300                         if (!context) {
1301                                 rc = -ENOMEM;
1302                                 dput(dentry);
1303                                 goto out_unlock;
1304                         }
1305                         context[len] = '\0';
1306                         rc = inode->i_op->getxattr(dentry,
1307                                                    XATTR_NAME_SELINUX,
1308                                                    context, len);
1309                 }
1310                 dput(dentry);
1311                 if (rc < 0) {
1312                         if (rc != -ENODATA) {
1313                                 printk(KERN_WARNING "SELinux: %s:  getxattr returned "
1314                                        "%d for dev=%s ino=%ld\n", __func__,
1315                                        -rc, inode->i_sb->s_id, inode->i_ino);
1316                                 kfree(context);
1317                                 goto out_unlock;
1318                         }
1319                         /* Map ENODATA to the default file SID */
1320                         sid = sbsec->def_sid;
1321                         rc = 0;
1322                 } else {
1323                         rc = security_context_to_sid_default(context, rc, &sid,
1324                                                              sbsec->def_sid,
1325                                                              GFP_NOFS);
1326                         if (rc) {
1327                                 char *dev = inode->i_sb->s_id;
1328                                 unsigned long ino = inode->i_ino;
1329
1330                                 if (rc == -EINVAL) {
1331                                         if (printk_ratelimit())
1332                                                 printk(KERN_NOTICE "SELinux: inode=%lu on dev=%s was found to have an invalid "
1333                                                         "context=%s.  This indicates you may need to relabel the inode or the "
1334                                                         "filesystem in question.\n", ino, dev, context);
1335                                 } else {
1336                                         printk(KERN_WARNING "SELinux: %s:  context_to_sid(%s) "
1337                                                "returned %d for dev=%s ino=%ld\n",
1338                                                __func__, context, -rc, dev, ino);
1339                                 }
1340                                 kfree(context);
1341                                 /* Leave with the unlabeled SID */
1342                                 rc = 0;
1343                                 break;
1344                         }
1345                 }
1346                 kfree(context);
1347                 isec->sid = sid;
1348                 break;
1349         case SECURITY_FS_USE_TASK:
1350                 isec->sid = isec->task_sid;
1351                 break;
1352         case SECURITY_FS_USE_TRANS:
1353                 /* Default to the fs SID. */
1354                 isec->sid = sbsec->sid;
1355
1356                 /* Try to obtain a transition SID. */
1357                 isec->sclass = inode_mode_to_security_class(inode->i_mode);
1358                 rc = security_transition_sid(isec->task_sid, sbsec->sid,
1359                                              isec->sclass, NULL, &sid);
1360                 if (rc)
1361                         goto out_unlock;
1362                 isec->sid = sid;
1363                 break;
1364         case SECURITY_FS_USE_MNTPOINT:
1365                 isec->sid = sbsec->mntpoint_sid;
1366                 break;
1367         default:
1368                 /* Default to the fs superblock SID. */
1369                 isec->sid = sbsec->sid;
1370
1371                 if ((sbsec->flags & SE_SBPROC) && !S_ISLNK(inode->i_mode)) {
1372                         if (opt_dentry) {
1373                                 isec->sclass = inode_mode_to_security_class(inode->i_mode);
1374                                 rc = selinux_proc_get_sid(opt_dentry,
1375                                                           isec->sclass,
1376                                                           &sid);
1377                                 if (rc)
1378                                         goto out_unlock;
1379                                 isec->sid = sid;
1380                         }
1381                 }
1382                 break;
1383         }
1384
1385         isec->initialized = 1;
1386
1387 out_unlock:
1388         mutex_unlock(&isec->lock);
1389 out:
1390         if (isec->sclass == SECCLASS_FILE)
1391                 isec->sclass = inode_mode_to_security_class(inode->i_mode);
1392         return rc;
1393 }
1394
1395 /* Convert a Linux signal to an access vector. */
1396 static inline u32 signal_to_av(int sig)
1397 {
1398         u32 perm = 0;
1399
1400         switch (sig) {
1401         case SIGCHLD:
1402                 /* Commonly granted from child to parent. */
1403                 perm = PROCESS__SIGCHLD;
1404                 break;
1405         case SIGKILL:
1406                 /* Cannot be caught or ignored */
1407                 perm = PROCESS__SIGKILL;
1408                 break;
1409         case SIGSTOP:
1410                 /* Cannot be caught or ignored */
1411                 perm = PROCESS__SIGSTOP;
1412                 break;
1413         default:
1414                 /* All other signals. */
1415                 perm = PROCESS__SIGNAL;
1416                 break;
1417         }
1418
1419         return perm;
1420 }
1421
1422 /*
1423  * Check permission between a pair of credentials
1424  * fork check, ptrace check, etc.
1425  */
1426 static int cred_has_perm(const struct cred *actor,
1427                          const struct cred *target,
1428                          u32 perms)
1429 {
1430         u32 asid = cred_sid(actor), tsid = cred_sid(target);
1431
1432         return avc_has_perm(asid, tsid, SECCLASS_PROCESS, perms, NULL);
1433 }
1434
1435 /*
1436  * Check permission between a pair of tasks, e.g. signal checks,
1437  * fork check, ptrace check, etc.
1438  * tsk1 is the actor and tsk2 is the target
1439  * - this uses the default subjective creds of tsk1
1440  */
1441 static int task_has_perm(const struct task_struct *tsk1,
1442                          const struct task_struct *tsk2,
1443                          u32 perms)
1444 {
1445         const struct task_security_struct *__tsec1, *__tsec2;
1446         u32 sid1, sid2;
1447
1448         rcu_read_lock();
1449         __tsec1 = __task_cred(tsk1)->security;  sid1 = __tsec1->sid;
1450         __tsec2 = __task_cred(tsk2)->security;  sid2 = __tsec2->sid;
1451         rcu_read_unlock();
1452         return avc_has_perm(sid1, sid2, SECCLASS_PROCESS, perms, NULL);
1453 }
1454
1455 /*
1456  * Check permission between current and another task, e.g. signal checks,
1457  * fork check, ptrace check, etc.
1458  * current is the actor and tsk2 is the target
1459  * - this uses current's subjective creds
1460  */
1461 static int current_has_perm(const struct task_struct *tsk,
1462                             u32 perms)
1463 {
1464         u32 sid, tsid;
1465
1466         sid = current_sid();
1467         tsid = task_sid(tsk);
1468         return avc_has_perm(sid, tsid, SECCLASS_PROCESS, perms, NULL);
1469 }
1470
1471 #if CAP_LAST_CAP > 63
1472 #error Fix SELinux to handle capabilities > 63.
1473 #endif
1474
1475 /* Check whether a task is allowed to use a capability. */
1476 static int cred_has_capability(const struct cred *cred,
1477                                int cap, int audit)
1478 {
1479         struct common_audit_data ad;
1480         struct av_decision avd;
1481         u16 sclass;
1482         u32 sid = cred_sid(cred);
1483         u32 av = CAP_TO_MASK(cap);
1484         int rc;
1485
1486         ad.type = LSM_AUDIT_DATA_CAP;
1487         ad.u.cap = cap;
1488
1489         switch (CAP_TO_INDEX(cap)) {
1490         case 0:
1491                 sclass = SECCLASS_CAPABILITY;
1492                 break;
1493         case 1:
1494                 sclass = SECCLASS_CAPABILITY2;
1495                 break;
1496         default:
1497                 printk(KERN_ERR
1498                        "SELinux:  out of range capability %d\n", cap);
1499                 BUG();
1500                 return -EINVAL;
1501         }
1502
1503         rc = avc_has_perm_noaudit(sid, sid, sclass, av, 0, &avd);
1504         if (audit == SECURITY_CAP_AUDIT) {
1505                 int rc2 = avc_audit(sid, sid, sclass, av, &avd, rc, &ad, 0);
1506                 if (rc2)
1507                         return rc2;
1508         }
1509         return rc;
1510 }
1511
1512 /* Check whether a task is allowed to use a system operation. */
1513 static int task_has_system(struct task_struct *tsk,
1514                            u32 perms)
1515 {
1516         u32 sid = task_sid(tsk);
1517
1518         return avc_has_perm(sid, SECINITSID_KERNEL,
1519                             SECCLASS_SYSTEM, perms, NULL);
1520 }
1521
1522 /* Check whether a task has a particular permission to an inode.
1523    The 'adp' parameter is optional and allows other audit
1524    data to be passed (e.g. the dentry). */
1525 static int inode_has_perm(const struct cred *cred,
1526                           struct inode *inode,
1527                           u32 perms,
1528                           struct common_audit_data *adp,
1529                           unsigned flags)
1530 {
1531         struct inode_security_struct *isec;
1532         u32 sid;
1533
1534         validate_creds(cred);
1535
1536         if (unlikely(IS_PRIVATE(inode)))
1537                 return 0;
1538
1539         sid = cred_sid(cred);
1540         isec = inode->i_security;
1541
1542         return avc_has_perm_flags(sid, isec->sid, isec->sclass, perms, adp, flags);
1543 }
1544
1545 /* Same as inode_has_perm, but pass explicit audit data containing
1546    the dentry to help the auditing code to more easily generate the
1547    pathname if needed. */
1548 static inline int dentry_has_perm(const struct cred *cred,
1549                                   struct dentry *dentry,
1550                                   u32 av)
1551 {
1552         struct inode *inode = dentry->d_inode;
1553         struct common_audit_data ad;
1554
1555         ad.type = LSM_AUDIT_DATA_DENTRY;
1556         ad.u.dentry = dentry;
1557         return inode_has_perm(cred, inode, av, &ad, 0);
1558 }
1559
1560 /* Same as inode_has_perm, but pass explicit audit data containing
1561    the path to help the auditing code to more easily generate the
1562    pathname if needed. */
1563 static inline int path_has_perm(const struct cred *cred,
1564                                 struct path *path,
1565                                 u32 av)
1566 {
1567         struct inode *inode = path->dentry->d_inode;
1568         struct common_audit_data ad;
1569
1570         ad.type = LSM_AUDIT_DATA_PATH;
1571         ad.u.path = *path;
1572         return inode_has_perm(cred, inode, av, &ad, 0);
1573 }
1574
1575 /* Check whether a task can use an open file descriptor to
1576    access an inode in a given way.  Check access to the
1577    descriptor itself, and then use dentry_has_perm to
1578    check a particular permission to the file.
1579    Access to the descriptor is implicitly granted if it
1580    has the same SID as the process.  If av is zero, then
1581    access to the file is not checked, e.g. for cases
1582    where only the descriptor is affected like seek. */
1583 static int file_has_perm(const struct cred *cred,
1584                          struct file *file,
1585                          u32 av)
1586 {
1587         struct file_security_struct *fsec = file->f_security;
1588         struct inode *inode = file_inode(file);
1589         struct common_audit_data ad;
1590         u32 sid = cred_sid(cred);
1591         int rc;
1592
1593         ad.type = LSM_AUDIT_DATA_PATH;
1594         ad.u.path = file->f_path;
1595
1596         if (sid != fsec->sid) {
1597                 rc = avc_has_perm(sid, fsec->sid,
1598                                   SECCLASS_FD,
1599                                   FD__USE,
1600                                   &ad);
1601                 if (rc)
1602                         goto out;
1603         }
1604
1605         /* av is zero if only checking access to the descriptor. */
1606         rc = 0;
1607         if (av)
1608                 rc = inode_has_perm(cred, inode, av, &ad, 0);
1609
1610 out:
1611         return rc;
1612 }
1613
1614 /* Check whether a task can create a file. */
1615 static int may_create(struct inode *dir,
1616                       struct dentry *dentry,
1617                       u16 tclass)
1618 {
1619         const struct task_security_struct *tsec = current_security();
1620         struct inode_security_struct *dsec;
1621         struct superblock_security_struct *sbsec;
1622         u32 sid, newsid;
1623         struct common_audit_data ad;
1624         int rc;
1625
1626         dsec = dir->i_security;
1627         sbsec = dir->i_sb->s_security;
1628
1629         sid = tsec->sid;
1630         newsid = tsec->create_sid;
1631
1632         ad.type = LSM_AUDIT_DATA_DENTRY;
1633         ad.u.dentry = dentry;
1634
1635         rc = avc_has_perm(sid, dsec->sid, SECCLASS_DIR,
1636                           DIR__ADD_NAME | DIR__SEARCH,
1637                           &ad);
1638         if (rc)
1639                 return rc;
1640
1641         if (!newsid || !(sbsec->flags & SE_SBLABELSUPP)) {
1642                 rc = security_transition_sid(sid, dsec->sid, tclass,
1643                                              &dentry->d_name, &newsid);
1644                 if (rc)
1645                         return rc;
1646         }
1647
1648         rc = avc_has_perm(sid, newsid, tclass, FILE__CREATE, &ad);
1649         if (rc)
1650                 return rc;
1651
1652         return avc_has_perm(newsid, sbsec->sid,
1653                             SECCLASS_FILESYSTEM,
1654                             FILESYSTEM__ASSOCIATE, &ad);
1655 }
1656
1657 /* Check whether a task can create a key. */
1658 static int may_create_key(u32 ksid,
1659                           struct task_struct *ctx)
1660 {
1661         u32 sid = task_sid(ctx);
1662
1663         return avc_has_perm(sid, ksid, SECCLASS_KEY, KEY__CREATE, NULL);
1664 }
1665
1666 #define MAY_LINK        0
1667 #define MAY_UNLINK      1
1668 #define MAY_RMDIR       2
1669
1670 /* Check whether a task can link, unlink, or rmdir a file/directory. */
1671 static int may_link(struct inode *dir,
1672                     struct dentry *dentry,
1673                     int kind)
1674
1675 {
1676         struct inode_security_struct *dsec, *isec;
1677         struct common_audit_data ad;
1678         u32 sid = current_sid();
1679         u32 av;
1680         int rc;
1681
1682         dsec = dir->i_security;
1683         isec = dentry->d_inode->i_security;
1684
1685         ad.type = LSM_AUDIT_DATA_DENTRY;
1686         ad.u.dentry = dentry;
1687
1688         av = DIR__SEARCH;
1689         av |= (kind ? DIR__REMOVE_NAME : DIR__ADD_NAME);
1690         rc = avc_has_perm(sid, dsec->sid, SECCLASS_DIR, av, &ad);
1691         if (rc)
1692                 return rc;
1693
1694         switch (kind) {
1695         case MAY_LINK:
1696                 av = FILE__LINK;
1697                 break;
1698         case MAY_UNLINK:
1699                 av = FILE__UNLINK;
1700                 break;
1701         case MAY_RMDIR:
1702                 av = DIR__RMDIR;
1703                 break;
1704         default:
1705                 printk(KERN_WARNING "SELinux: %s:  unrecognized kind %d\n",
1706                         __func__, kind);
1707                 return 0;
1708         }
1709
1710         rc = avc_has_perm(sid, isec->sid, isec->sclass, av, &ad);
1711         return rc;
1712 }
1713
1714 static inline int may_rename(struct inode *old_dir,
1715                              struct dentry *old_dentry,
1716                              struct inode *new_dir,
1717                              struct dentry *new_dentry)
1718 {
1719         struct inode_security_struct *old_dsec, *new_dsec, *old_isec, *new_isec;
1720         struct common_audit_data ad;
1721         u32 sid = current_sid();
1722         u32 av;
1723         int old_is_dir, new_is_dir;
1724         int rc;
1725
1726         old_dsec = old_dir->i_security;
1727         old_isec = old_dentry->d_inode->i_security;
1728         old_is_dir = S_ISDIR(old_dentry->d_inode->i_mode);
1729         new_dsec = new_dir->i_security;
1730
1731         ad.type = LSM_AUDIT_DATA_DENTRY;
1732
1733         ad.u.dentry = old_dentry;
1734         rc = avc_has_perm(sid, old_dsec->sid, SECCLASS_DIR,
1735                           DIR__REMOVE_NAME | DIR__SEARCH, &ad);
1736         if (rc)
1737                 return rc;
1738         rc = avc_has_perm(sid, old_isec->sid,
1739                           old_isec->sclass, FILE__RENAME, &ad);
1740         if (rc)
1741                 return rc;
1742         if (old_is_dir && new_dir != old_dir) {
1743                 rc = avc_has_perm(sid, old_isec->sid,
1744                                   old_isec->sclass, DIR__REPARENT, &ad);
1745                 if (rc)
1746                         return rc;
1747         }
1748
1749         ad.u.dentry = new_dentry;
1750         av = DIR__ADD_NAME | DIR__SEARCH;
1751         if (new_dentry->d_inode)
1752                 av |= DIR__REMOVE_NAME;
1753         rc = avc_has_perm(sid, new_dsec->sid, SECCLASS_DIR, av, &ad);
1754         if (rc)
1755                 return rc;
1756         if (new_dentry->d_inode) {
1757                 new_isec = new_dentry->d_inode->i_security;
1758                 new_is_dir = S_ISDIR(new_dentry->d_inode->i_mode);
1759                 rc = avc_has_perm(sid, new_isec->sid,
1760                                   new_isec->sclass,
1761                                   (new_is_dir ? DIR__RMDIR : FILE__UNLINK), &ad);
1762                 if (rc)
1763                         return rc;
1764         }
1765
1766         return 0;
1767 }
1768
1769 /* Check whether a task can perform a filesystem operation. */
1770 static int superblock_has_perm(const struct cred *cred,
1771                                struct super_block *sb,
1772                                u32 perms,
1773                                struct common_audit_data *ad)
1774 {
1775         struct superblock_security_struct *sbsec;
1776         u32 sid = cred_sid(cred);
1777
1778         sbsec = sb->s_security;
1779         return avc_has_perm(sid, sbsec->sid, SECCLASS_FILESYSTEM, perms, ad);
1780 }
1781
1782 /* Convert a Linux mode and permission mask to an access vector. */
1783 static inline u32 file_mask_to_av(int mode, int mask)
1784 {
1785         u32 av = 0;
1786
1787         if (!S_ISDIR(mode)) {
1788                 if (mask & MAY_EXEC)
1789                         av |= FILE__EXECUTE;
1790                 if (mask & MAY_READ)
1791                         av |= FILE__READ;
1792
1793                 if (mask & MAY_APPEND)
1794                         av |= FILE__APPEND;
1795                 else if (mask & MAY_WRITE)
1796                         av |= FILE__WRITE;
1797
1798         } else {
1799                 if (mask & MAY_EXEC)
1800                         av |= DIR__SEARCH;
1801                 if (mask & MAY_WRITE)
1802                         av |= DIR__WRITE;
1803                 if (mask & MAY_READ)
1804                         av |= DIR__READ;
1805         }
1806
1807         return av;
1808 }
1809
1810 /* Convert a Linux file to an access vector. */
1811 static inline u32 file_to_av(struct file *file)
1812 {
1813         u32 av = 0;
1814
1815         if (file->f_mode & FMODE_READ)
1816                 av |= FILE__READ;
1817         if (file->f_mode & FMODE_WRITE) {
1818                 if (file->f_flags & O_APPEND)
1819                         av |= FILE__APPEND;
1820                 else
1821                         av |= FILE__WRITE;
1822         }
1823         if (!av) {
1824                 /*
1825                  * Special file opened with flags 3 for ioctl-only use.
1826                  */
1827                 av = FILE__IOCTL;
1828         }
1829
1830         return av;
1831 }
1832
1833 /*
1834  * Convert a file to an access vector and include the correct open
1835  * open permission.
1836  */
1837 static inline u32 open_file_to_av(struct file *file)
1838 {
1839         u32 av = file_to_av(file);
1840
1841         if (selinux_policycap_openperm)
1842                 av |= FILE__OPEN;
1843
1844         return av;
1845 }
1846
1847 /* Hook functions begin here. */
1848
1849 static int selinux_ptrace_access_check(struct task_struct *child,
1850                                      unsigned int mode)
1851 {
1852         int rc;
1853
1854         rc = cap_ptrace_access_check(child, mode);
1855         if (rc)
1856                 return rc;
1857
1858         if (mode & PTRACE_MODE_READ) {
1859                 u32 sid = current_sid();
1860                 u32 csid = task_sid(child);
1861                 return avc_has_perm(sid, csid, SECCLASS_FILE, FILE__READ, NULL);
1862         }
1863
1864         return current_has_perm(child, PROCESS__PTRACE);
1865 }
1866
1867 static int selinux_ptrace_traceme(struct task_struct *parent)
1868 {
1869         int rc;
1870
1871         rc = cap_ptrace_traceme(parent);
1872         if (rc)
1873                 return rc;
1874
1875         return task_has_perm(parent, current, PROCESS__PTRACE);
1876 }
1877
1878 static int selinux_capget(struct task_struct *target, kernel_cap_t *effective,
1879                           kernel_cap_t *inheritable, kernel_cap_t *permitted)
1880 {
1881         int error;
1882
1883         error = current_has_perm(target, PROCESS__GETCAP);
1884         if (error)
1885                 return error;
1886
1887         return cap_capget(target, effective, inheritable, permitted);
1888 }
1889
1890 static int selinux_capset(struct cred *new, const struct cred *old,
1891                           const kernel_cap_t *effective,
1892                           const kernel_cap_t *inheritable,
1893                           const kernel_cap_t *permitted)
1894 {
1895         int error;
1896
1897         error = cap_capset(new, old,
1898                                       effective, inheritable, permitted);
1899         if (error)
1900                 return error;
1901
1902         return cred_has_perm(old, new, PROCESS__SETCAP);
1903 }
1904
1905 /*
1906  * (This comment used to live with the selinux_task_setuid hook,
1907  * which was removed).
1908  *
1909  * Since setuid only affects the current process, and since the SELinux
1910  * controls are not based on the Linux identity attributes, SELinux does not
1911  * need to control this operation.  However, SELinux does control the use of
1912  * the CAP_SETUID and CAP_SETGID capabilities using the capable hook.
1913  */
1914
1915 static int selinux_capable(const struct cred *cred, struct user_namespace *ns,
1916                            int cap, int audit)
1917 {
1918         int rc;
1919
1920         rc = cap_capable(cred, ns, cap, audit);
1921         if (rc)
1922                 return rc;
1923
1924         return cred_has_capability(cred, cap, audit);
1925 }
1926
1927 static int selinux_quotactl(int cmds, int type, int id, struct super_block *sb)
1928 {
1929         const struct cred *cred = current_cred();
1930         int rc = 0;
1931
1932         if (!sb)
1933                 return 0;
1934
1935         switch (cmds) {
1936         case Q_SYNC:
1937         case Q_QUOTAON:
1938         case Q_QUOTAOFF:
1939         case Q_SETINFO:
1940         case Q_SETQUOTA:
1941                 rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAMOD, NULL);
1942                 break;
1943         case Q_GETFMT:
1944         case Q_GETINFO:
1945         case Q_GETQUOTA:
1946                 rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAGET, NULL);
1947                 break;
1948         default:
1949                 rc = 0;  /* let the kernel handle invalid cmds */
1950                 break;
1951         }
1952         return rc;
1953 }
1954
1955 static int selinux_quota_on(struct dentry *dentry)
1956 {
1957         const struct cred *cred = current_cred();
1958
1959         return dentry_has_perm(cred, dentry, FILE__QUOTAON);
1960 }
1961
1962 static int selinux_syslog(int type)
1963 {
1964         int rc;
1965
1966         switch (type) {
1967         case SYSLOG_ACTION_READ_ALL:    /* Read last kernel messages */
1968         case SYSLOG_ACTION_SIZE_BUFFER: /* Return size of the log buffer */
1969                 rc = task_has_system(current, SYSTEM__SYSLOG_READ);
1970                 break;
1971         case SYSLOG_ACTION_CONSOLE_OFF: /* Disable logging to console */
1972         case SYSLOG_ACTION_CONSOLE_ON:  /* Enable logging to console */
1973         /* Set level of messages printed to console */
1974         case SYSLOG_ACTION_CONSOLE_LEVEL:
1975                 rc = task_has_system(current, SYSTEM__SYSLOG_CONSOLE);
1976                 break;
1977         case SYSLOG_ACTION_CLOSE:       /* Close log */
1978         case SYSLOG_ACTION_OPEN:        /* Open log */
1979         case SYSLOG_ACTION_READ:        /* Read from log */
1980         case SYSLOG_ACTION_READ_CLEAR:  /* Read/clear last kernel messages */
1981         case SYSLOG_ACTION_CLEAR:       /* Clear ring buffer */
1982         default:
1983                 rc = task_has_system(current, SYSTEM__SYSLOG_MOD);
1984                 break;
1985         }
1986         return rc;
1987 }
1988
1989 /*
1990  * Check that a process has enough memory to allocate a new virtual
1991  * mapping. 0 means there is enough memory for the allocation to
1992  * succeed and -ENOMEM implies there is not.
1993  *
1994  * Do not audit the selinux permission check, as this is applied to all
1995  * processes that allocate mappings.
1996  */
1997 static int selinux_vm_enough_memory(struct mm_struct *mm, long pages)
1998 {
1999         int rc, cap_sys_admin = 0;
2000
2001         rc = selinux_capable(current_cred(), &init_user_ns, CAP_SYS_ADMIN,
2002                              SECURITY_CAP_NOAUDIT);
2003         if (rc == 0)
2004                 cap_sys_admin = 1;
2005
2006         return __vm_enough_memory(mm, pages, cap_sys_admin);
2007 }
2008
2009 /* binprm security operations */
2010
2011 static int selinux_bprm_set_creds(struct linux_binprm *bprm)
2012 {
2013         const struct task_security_struct *old_tsec;
2014         struct task_security_struct *new_tsec;
2015         struct inode_security_struct *isec;
2016         struct common_audit_data ad;
2017         struct inode *inode = file_inode(bprm->file);
2018         int rc;
2019
2020         rc = cap_bprm_set_creds(bprm);
2021         if (rc)
2022                 return rc;
2023
2024         /* SELinux context only depends on initial program or script and not
2025          * the script interpreter */
2026         if (bprm->cred_prepared)
2027                 return 0;
2028
2029         old_tsec = current_security();
2030         new_tsec = bprm->cred->security;
2031         isec = inode->i_security;
2032
2033         /* Default to the current task SID. */
2034         new_tsec->sid = old_tsec->sid;
2035         new_tsec->osid = old_tsec->sid;
2036
2037         /* Reset fs, key, and sock SIDs on execve. */
2038         new_tsec->create_sid = 0;
2039         new_tsec->keycreate_sid = 0;
2040         new_tsec->sockcreate_sid = 0;
2041
2042         if (old_tsec->exec_sid) {
2043                 new_tsec->sid = old_tsec->exec_sid;
2044                 /* Reset exec SID on execve. */
2045                 new_tsec->exec_sid = 0;
2046
2047                 /*
2048                  * Minimize confusion: if no_new_privs and a transition is
2049                  * explicitly requested, then fail the exec.
2050                  */
2051                 if (bprm->unsafe & LSM_UNSAFE_NO_NEW_PRIVS)
2052                         return -EPERM;
2053         } else {
2054                 /* Check for a default transition on this program. */
2055                 rc = security_transition_sid(old_tsec->sid, isec->sid,
2056                                              SECCLASS_PROCESS, NULL,
2057                                              &new_tsec->sid);
2058                 if (rc)
2059                         return rc;
2060         }
2061
2062         ad.type = LSM_AUDIT_DATA_PATH;
2063         ad.u.path = bprm->file->f_path;
2064
2065         if ((bprm->file->f_path.mnt->mnt_flags & MNT_NOSUID) ||
2066             (bprm->unsafe & LSM_UNSAFE_NO_NEW_PRIVS))
2067                 new_tsec->sid = old_tsec->sid;
2068
2069         if (new_tsec->sid == old_tsec->sid) {
2070                 rc = avc_has_perm(old_tsec->sid, isec->sid,
2071                                   SECCLASS_FILE, FILE__EXECUTE_NO_TRANS, &ad);
2072                 if (rc)
2073                         return rc;
2074         } else {
2075                 /* Check permissions for the transition. */
2076                 rc = avc_has_perm(old_tsec->sid, new_tsec->sid,
2077                                   SECCLASS_PROCESS, PROCESS__TRANSITION, &ad);
2078                 if (rc)
2079                         return rc;
2080
2081                 rc = avc_has_perm(new_tsec->sid, isec->sid,
2082                                   SECCLASS_FILE, FILE__ENTRYPOINT, &ad);
2083                 if (rc)
2084                         return rc;
2085
2086                 /* Check for shared state */
2087                 if (bprm->unsafe & LSM_UNSAFE_SHARE) {
2088                         rc = avc_has_perm(old_tsec->sid, new_tsec->sid,
2089                                           SECCLASS_PROCESS, PROCESS__SHARE,
2090                                           NULL);
2091                         if (rc)
2092                                 return -EPERM;
2093                 }
2094
2095                 /* Make sure that anyone attempting to ptrace over a task that
2096                  * changes its SID has the appropriate permit */
2097                 if (bprm->unsafe &
2098                     (LSM_UNSAFE_PTRACE | LSM_UNSAFE_PTRACE_CAP)) {
2099                         struct task_struct *tracer;
2100                         struct task_security_struct *sec;
2101                         u32 ptsid = 0;
2102
2103                         rcu_read_lock();
2104                         tracer = ptrace_parent(current);
2105                         if (likely(tracer != NULL)) {
2106                                 sec = __task_cred(tracer)->security;
2107                                 ptsid = sec->sid;
2108                         }
2109                         rcu_read_unlock();
2110
2111                         if (ptsid != 0) {
2112                                 rc = avc_has_perm(ptsid, new_tsec->sid,
2113                                                   SECCLASS_PROCESS,
2114                                                   PROCESS__PTRACE, NULL);
2115                                 if (rc)
2116                                         return -EPERM;
2117                         }
2118                 }
2119
2120                 /* Clear any possibly unsafe personality bits on exec: */
2121                 bprm->per_clear |= PER_CLEAR_ON_SETID;
2122         }
2123
2124         return 0;
2125 }
2126
2127 static int selinux_bprm_secureexec(struct linux_binprm *bprm)
2128 {
2129         const struct task_security_struct *tsec = current_security();
2130         u32 sid, osid;
2131         int atsecure = 0;
2132
2133         sid = tsec->sid;
2134         osid = tsec->osid;
2135
2136         if (osid != sid) {
2137                 /* Enable secure mode for SIDs transitions unless
2138                    the noatsecure permission is granted between
2139                    the two SIDs, i.e. ahp returns 0. */
2140                 atsecure = avc_has_perm(osid, sid,
2141                                         SECCLASS_PROCESS,
2142                                         PROCESS__NOATSECURE, NULL);
2143         }
2144
2145         return (atsecure || cap_bprm_secureexec(bprm));
2146 }
2147
2148 static int match_file(const void *p, struct file *file, unsigned fd)
2149 {
2150         return file_has_perm(p, file, file_to_av(file)) ? fd + 1 : 0;
2151 }
2152
2153 /* Derived from fs/exec.c:flush_old_files. */
2154 static inline void flush_unauthorized_files(const struct cred *cred,
2155                                             struct files_struct *files)
2156 {
2157         struct file *file, *devnull = NULL;
2158         struct tty_struct *tty;
2159         int drop_tty = 0;
2160         unsigned n;
2161
2162         tty = get_current_tty();
2163         if (tty) {
2164                 spin_lock(&tty_files_lock);
2165                 if (!list_empty(&tty->tty_files)) {
2166                         struct tty_file_private *file_priv;
2167
2168                         /* Revalidate access to controlling tty.
2169                            Use path_has_perm on the tty path directly rather
2170                            than using file_has_perm, as this particular open
2171                            file may belong to another process and we are only
2172                            interested in the inode-based check here. */
2173                         file_priv = list_first_entry(&tty->tty_files,
2174                                                 struct tty_file_private, list);
2175                         file = file_priv->file;
2176                         if (path_has_perm(cred, &file->f_path, FILE__READ | FILE__WRITE))
2177                                 drop_tty = 1;
2178                 }
2179                 spin_unlock(&tty_files_lock);
2180                 tty_kref_put(tty);
2181         }
2182         /* Reset controlling tty. */
2183         if (drop_tty)
2184                 no_tty();
2185
2186         /* Revalidate access to inherited open files. */
2187         n = iterate_fd(files, 0, match_file, cred);
2188         if (!n) /* none found? */
2189                 return;
2190
2191         devnull = dentry_open(&selinux_null, O_RDWR, cred);
2192         if (IS_ERR(devnull))
2193                 devnull = NULL;
2194         /* replace all the matching ones with this */
2195         do {
2196                 replace_fd(n - 1, devnull, 0);
2197         } while ((n = iterate_fd(files, n, match_file, cred)) != 0);
2198         if (devnull)
2199                 fput(devnull);
2200 }
2201
2202 /*
2203  * Prepare a process for imminent new credential changes due to exec
2204  */
2205 static void selinux_bprm_committing_creds(struct linux_binprm *bprm)
2206 {
2207         struct task_security_struct *new_tsec;
2208         struct rlimit *rlim, *initrlim;
2209         int rc, i;
2210
2211         new_tsec = bprm->cred->security;
2212         if (new_tsec->sid == new_tsec->osid)
2213                 return;
2214
2215         /* Close files for which the new task SID is not authorized. */
2216         flush_unauthorized_files(bprm->cred, current->files);
2217
2218         /* Always clear parent death signal on SID transitions. */
2219         current->pdeath_signal = 0;
2220
2221         /* Check whether the new SID can inherit resource limits from the old
2222          * SID.  If not, reset all soft limits to the lower of the current
2223          * task's hard limit and the init task's soft limit.
2224          *
2225          * Note that the setting of hard limits (even to lower them) can be
2226          * controlled by the setrlimit check.  The inclusion of the init task's
2227          * soft limit into the computation is to avoid resetting soft limits
2228          * higher than the default soft limit for cases where the default is
2229          * lower than the hard limit, e.g. RLIMIT_CORE or RLIMIT_STACK.
2230          */
2231         rc = avc_has_perm(new_tsec->osid, new_tsec->sid, SECCLASS_PROCESS,
2232                           PROCESS__RLIMITINH, NULL);
2233         if (rc) {
2234                 /* protect against do_prlimit() */
2235                 task_lock(current);
2236                 for (i = 0; i < RLIM_NLIMITS; i++) {
2237                         rlim = current->signal->rlim + i;
2238                         initrlim = init_task.signal->rlim + i;
2239                         rlim->rlim_cur = min(rlim->rlim_max, initrlim->rlim_cur);
2240                 }
2241                 task_unlock(current);
2242                 update_rlimit_cpu(current, rlimit(RLIMIT_CPU));
2243         }
2244 }
2245
2246 /*
2247  * Clean up the process immediately after the installation of new credentials
2248  * due to exec
2249  */
2250 static void selinux_bprm_committed_creds(struct linux_binprm *bprm)
2251 {
2252         const struct task_security_struct *tsec = current_security();
2253         struct itimerval itimer;
2254         u32 osid, sid;
2255         int rc, i;
2256
2257         osid = tsec->osid;
2258         sid = tsec->sid;
2259
2260         if (sid == osid)
2261                 return;
2262
2263         /* Check whether the new SID can inherit signal state from the old SID.
2264          * If not, clear itimers to avoid subsequent signal generation and
2265          * flush and unblock signals.
2266          *
2267          * This must occur _after_ the task SID has been updated so that any
2268          * kill done after the flush will be checked against the new SID.
2269          */
2270         rc = avc_has_perm(osid, sid, SECCLASS_PROCESS, PROCESS__SIGINH, NULL);
2271         if (rc) {
2272                 memset(&itimer, 0, sizeof itimer);
2273                 for (i = 0; i < 3; i++)
2274                         do_setitimer(i, &itimer, NULL);
2275                 spin_lock_irq(&current->sighand->siglock);
2276                 if (!(current->signal->flags & SIGNAL_GROUP_EXIT)) {
2277                         __flush_signals(current);
2278                         flush_signal_handlers(current, 1);
2279                         sigemptyset(&current->blocked);
2280                 }
2281                 spin_unlock_irq(&current->sighand->siglock);
2282         }
2283
2284         /* Wake up the parent if it is waiting so that it can recheck
2285          * wait permission to the new task SID. */
2286         read_lock(&tasklist_lock);
2287         __wake_up_parent(current, current->real_parent);
2288         read_unlock(&tasklist_lock);
2289 }
2290
2291 /* superblock security operations */
2292
2293 static int selinux_sb_alloc_security(struct super_block *sb)
2294 {
2295         return superblock_alloc_security(sb);
2296 }
2297
2298 static void selinux_sb_free_security(struct super_block *sb)
2299 {
2300         superblock_free_security(sb);
2301 }
2302
2303 static inline int match_prefix(char *prefix, int plen, char *option, int olen)
2304 {
2305         if (plen > olen)
2306                 return 0;
2307
2308         return !memcmp(prefix, option, plen);
2309 }
2310
2311 static inline int selinux_option(char *option, int len)
2312 {
2313         return (match_prefix(CONTEXT_STR, sizeof(CONTEXT_STR)-1, option, len) ||
2314                 match_prefix(FSCONTEXT_STR, sizeof(FSCONTEXT_STR)-1, option, len) ||
2315                 match_prefix(DEFCONTEXT_STR, sizeof(DEFCONTEXT_STR)-1, option, len) ||
2316                 match_prefix(ROOTCONTEXT_STR, sizeof(ROOTCONTEXT_STR)-1, option, len) ||
2317                 match_prefix(LABELSUPP_STR, sizeof(LABELSUPP_STR)-1, option, len));
2318 }
2319
2320 static inline void take_option(char **to, char *from, int *first, int len)
2321 {
2322         if (!*first) {
2323                 **to = ',';
2324                 *to += 1;
2325         } else
2326                 *first = 0;
2327         memcpy(*to, from, len);
2328         *to += len;
2329 }
2330
2331 static inline void take_selinux_option(char **to, char *from, int *first,
2332                                        int len)
2333 {
2334         int current_size = 0;
2335
2336         if (!*first) {
2337                 **to = '|';
2338                 *to += 1;
2339         } else
2340                 *first = 0;
2341
2342         while (current_size < len) {
2343                 if (*from != '"') {
2344                         **to = *from;
2345                         *to += 1;
2346                 }
2347                 from += 1;
2348                 current_size += 1;
2349         }
2350 }
2351
2352 static int selinux_sb_copy_data(char *orig, char *copy)
2353 {
2354         int fnosec, fsec, rc = 0;
2355         char *in_save, *in_curr, *in_end;
2356         char *sec_curr, *nosec_save, *nosec;
2357         int open_quote = 0;
2358
2359         in_curr = orig;
2360         sec_curr = copy;
2361
2362         nosec = (char *)get_zeroed_page(GFP_KERNEL);
2363         if (!nosec) {
2364                 rc = -ENOMEM;
2365                 goto out;
2366         }
2367
2368         nosec_save = nosec;
2369         fnosec = fsec = 1;
2370         in_save = in_end = orig;
2371
2372         do {
2373                 if (*in_end == '"')
2374                         open_quote = !open_quote;
2375                 if ((*in_end == ',' && open_quote == 0) ||
2376                                 *in_end == '\0') {
2377                         int len = in_end - in_curr;
2378
2379                         if (selinux_option(in_curr, len))
2380                                 take_selinux_option(&sec_curr, in_curr, &fsec, len);
2381                         else
2382                                 take_option(&nosec, in_curr, &fnosec, len);
2383
2384                         in_curr = in_end + 1;
2385                 }
2386         } while (*in_end++);
2387
2388         strcpy(in_save, nosec_save);
2389         free_page((unsigned long)nosec_save);
2390 out:
2391         return rc;
2392 }
2393
2394 static int selinux_sb_remount(struct super_block *sb, void *data)
2395 {
2396         int rc, i, *flags;
2397         struct security_mnt_opts opts;
2398         char *secdata, **mount_options;
2399         struct superblock_security_struct *sbsec = sb->s_security;
2400
2401         if (!(sbsec->flags & SE_SBINITIALIZED))
2402                 return 0;
2403
2404         if (!data)
2405                 return 0;
2406
2407         if (sb->s_type->fs_flags & FS_BINARY_MOUNTDATA)
2408                 return 0;
2409
2410         security_init_mnt_opts(&opts);
2411         secdata = alloc_secdata();
2412         if (!secdata)
2413                 return -ENOMEM;
2414         rc = selinux_sb_copy_data(data, secdata);
2415         if (rc)
2416                 goto out_free_secdata;
2417
2418         rc = selinux_parse_opts_str(secdata, &opts);
2419         if (rc)
2420                 goto out_free_secdata;
2421
2422         mount_options = opts.mnt_opts;
2423         flags = opts.mnt_opts_flags;
2424
2425         for (i = 0; i < opts.num_mnt_opts; i++) {
2426                 u32 sid;
2427                 size_t len;
2428
2429                 if (flags[i] == SE_SBLABELSUPP)
2430                         continue;
2431                 len = strlen(mount_options[i]);
2432                 rc = security_context_to_sid(mount_options[i], len, &sid);
2433                 if (rc) {
2434                         printk(KERN_WARNING "SELinux: security_context_to_sid"
2435                                "(%s) failed for (dev %s, type %s) errno=%d\n",
2436                                mount_options[i], sb->s_id, sb->s_type->name, rc);
2437                         goto out_free_opts;
2438                 }
2439                 rc = -EINVAL;
2440                 switch (flags[i]) {
2441                 case FSCONTEXT_MNT:
2442                         if (bad_option(sbsec, FSCONTEXT_MNT, sbsec->sid, sid))
2443                                 goto out_bad_option;
2444                         break;
2445                 case CONTEXT_MNT:
2446                         if (bad_option(sbsec, CONTEXT_MNT, sbsec->mntpoint_sid, sid))
2447                                 goto out_bad_option;
2448                         break;
2449                 case ROOTCONTEXT_MNT: {
2450                         struct inode_security_struct *root_isec;
2451                         root_isec = sb->s_root->d_inode->i_security;
2452
2453                         if (bad_option(sbsec, ROOTCONTEXT_MNT, root_isec->sid, sid))
2454                                 goto out_bad_option;
2455                         break;
2456                 }
2457                 case DEFCONTEXT_MNT:
2458                         if (bad_option(sbsec, DEFCONTEXT_MNT, sbsec->def_sid, sid))
2459                                 goto out_bad_option;
2460                         break;
2461                 default:
2462                         goto out_free_opts;
2463                 }
2464         }
2465
2466         rc = 0;
2467 out_free_opts:
2468         security_free_mnt_opts(&opts);
2469 out_free_secdata:
2470         free_secdata(secdata);
2471         return rc;
2472 out_bad_option:
2473         printk(KERN_WARNING "SELinux: unable to change security options "
2474                "during remount (dev %s, type=%s)\n", sb->s_id,
2475                sb->s_type->name);
2476         goto out_free_opts;
2477 }
2478
2479 static int selinux_sb_kern_mount(struct super_block *sb, int flags, void *data)
2480 {
2481         const struct cred *cred = current_cred();
2482         struct common_audit_data ad;
2483         int rc;
2484
2485         rc = superblock_doinit(sb, data);
2486         if (rc)
2487                 return rc;
2488
2489         /* Allow all mounts performed by the kernel */
2490         if (flags & MS_KERNMOUNT)
2491                 return 0;
2492
2493         ad.type = LSM_AUDIT_DATA_DENTRY;
2494         ad.u.dentry = sb->s_root;
2495         return superblock_has_perm(cred, sb, FILESYSTEM__MOUNT, &ad);
2496 }
2497
2498 static int selinux_sb_statfs(struct dentry *dentry)
2499 {
2500         const struct cred *cred = current_cred();
2501         struct common_audit_data ad;
2502
2503         ad.type = LSM_AUDIT_DATA_DENTRY;
2504         ad.u.dentry = dentry->d_sb->s_root;
2505         return superblock_has_perm(cred, dentry->d_sb, FILESYSTEM__GETATTR, &ad);
2506 }
2507
2508 static int selinux_mount(const char *dev_name,
2509                          struct path *path,
2510                          const char *type,
2511                          unsigned long flags,
2512                          void *data)
2513 {
2514         const struct cred *cred = current_cred();
2515
2516         if (flags & MS_REMOUNT)
2517                 return superblock_has_perm(cred, path->dentry->d_sb,
2518                                            FILESYSTEM__REMOUNT, NULL);
2519         else
2520                 return path_has_perm(cred, path, FILE__MOUNTON);
2521 }
2522
2523 static int selinux_umount(struct vfsmount *mnt, int flags)
2524 {
2525         const struct cred *cred = current_cred();
2526
2527         return superblock_has_perm(cred, mnt->mnt_sb,
2528                                    FILESYSTEM__UNMOUNT, NULL);
2529 }
2530
2531 /* inode security operations */
2532
2533 static int selinux_inode_alloc_security(struct inode *inode)
2534 {
2535         return inode_alloc_security(inode);
2536 }
2537
2538 static void selinux_inode_free_security(struct inode *inode)
2539 {
2540         inode_free_security(inode);
2541 }
2542
2543 static int selinux_dentry_init_security(struct dentry *dentry, int mode,
2544                                         struct qstr *name, void **ctx,
2545                                         u32 *ctxlen)
2546 {
2547         const struct cred *cred = current_cred();
2548         struct task_security_struct *tsec;
2549         struct inode_security_struct *dsec;
2550         struct superblock_security_struct *sbsec;
2551         struct inode *dir = dentry->d_parent->d_inode;
2552         u32 newsid;
2553         int rc;
2554
2555         tsec = cred->security;
2556         dsec = dir->i_security;
2557         sbsec = dir->i_sb->s_security;
2558
2559         if (tsec->create_sid && sbsec->behavior != SECURITY_FS_USE_MNTPOINT) {
2560                 newsid = tsec->create_sid;
2561         } else {
2562                 rc = security_transition_sid(tsec->sid, dsec->sid,
2563                                              inode_mode_to_security_class(mode),
2564                                              name,
2565                                              &newsid);
2566                 if (rc) {
2567                         printk(KERN_WARNING
2568                                 "%s: security_transition_sid failed, rc=%d\n",
2569                                __func__, -rc);
2570                         return rc;
2571                 }
2572         }
2573
2574         return security_sid_to_context(newsid, (char **)ctx, ctxlen);
2575 }
2576
2577 static int selinux_inode_init_security(struct inode *inode, struct inode *dir,
2578                                        const struct qstr *qstr, char **name,
2579                                        void **value, size_t *len)
2580 {
2581         const struct task_security_struct *tsec = current_security();
2582         struct inode_security_struct *dsec;
2583         struct superblock_security_struct *sbsec;
2584         u32 sid, newsid, clen;
2585         int rc;
2586         char *namep = NULL, *context;
2587
2588         dsec = dir->i_security;
2589         sbsec = dir->i_sb->s_security;
2590
2591         sid = tsec->sid;
2592         newsid = tsec->create_sid;
2593
2594         if ((sbsec->flags & SE_SBINITIALIZED) &&
2595             (sbsec->behavior == SECURITY_FS_USE_MNTPOINT))
2596                 newsid = sbsec->mntpoint_sid;
2597         else if (!newsid || !(sbsec->flags & SE_SBLABELSUPP)) {
2598                 rc = security_transition_sid(sid, dsec->sid,
2599                                              inode_mode_to_security_class(inode->i_mode),
2600                                              qstr, &newsid);
2601                 if (rc) {
2602                         printk(KERN_WARNING "%s:  "
2603                                "security_transition_sid failed, rc=%d (dev=%s "
2604                                "ino=%ld)\n",
2605                                __func__,
2606                                -rc, inode->i_sb->s_id, inode->i_ino);
2607                         return rc;
2608                 }
2609         }
2610
2611         /* Possibly defer initialization to selinux_complete_init. */
2612         if (sbsec->flags & SE_SBINITIALIZED) {
2613                 struct inode_security_struct *isec = inode->i_security;
2614                 isec->sclass = inode_mode_to_security_class(inode->i_mode);
2615                 isec->sid = newsid;
2616                 isec->initialized = 1;
2617         }
2618
2619         if (!ss_initialized || !(sbsec->flags & SE_SBLABELSUPP))
2620                 return -EOPNOTSUPP;
2621
2622         if (name) {
2623                 namep = kstrdup(XATTR_SELINUX_SUFFIX, GFP_NOFS);
2624                 if (!namep)
2625                         return -ENOMEM;
2626                 *name = namep;
2627         }
2628
2629         if (value && len) {
2630                 rc = security_sid_to_context_force(newsid, &context, &clen);
2631                 if (rc) {
2632                         kfree(namep);
2633                         return rc;
2634                 }
2635                 *value = context;
2636                 *len = clen;
2637         }
2638
2639         return 0;
2640 }
2641
2642 static int selinux_inode_create(struct inode *dir, struct dentry *dentry, umode_t mode)
2643 {
2644         return may_create(dir, dentry, SECCLASS_FILE);
2645 }
2646
2647 static int selinux_inode_link(struct dentry *old_dentry, struct inode *dir, struct dentry *new_dentry)
2648 {
2649         return may_link(dir, old_dentry, MAY_LINK);
2650 }
2651
2652 static int selinux_inode_unlink(struct inode *dir, struct dentry *dentry)
2653 {
2654         return may_link(dir, dentry, MAY_UNLINK);
2655 }
2656
2657 static int selinux_inode_symlink(struct inode *dir, struct dentry *dentry, const char *name)
2658 {
2659         return may_create(dir, dentry, SECCLASS_LNK_FILE);
2660 }
2661
2662 static int selinux_inode_mkdir(struct inode *dir, struct dentry *dentry, umode_t mask)
2663 {
2664         return may_create(dir, dentry, SECCLASS_DIR);
2665 }
2666
2667 static int selinux_inode_rmdir(struct inode *dir, struct dentry *dentry)
2668 {
2669         return may_link(dir, dentry, MAY_RMDIR);
2670 }
2671
2672 static int selinux_inode_mknod(struct inode *dir, struct dentry *dentry, umode_t mode, dev_t dev)
2673 {
2674         return may_create(dir, dentry, inode_mode_to_security_class(mode));
2675 }
2676
2677 static int selinux_inode_rename(struct inode *old_inode, struct dentry *old_dentry,
2678                                 struct inode *new_inode, struct dentry *new_dentry)
2679 {
2680         return may_rename(old_inode, old_dentry, new_inode, new_dentry);
2681 }
2682
2683 static int selinux_inode_readlink(struct dentry *dentry)
2684 {
2685         const struct cred *cred = current_cred();
2686
2687         return dentry_has_perm(cred, dentry, FILE__READ);
2688 }
2689
2690 static int selinux_inode_follow_link(struct dentry *dentry, struct nameidata *nameidata)
2691 {
2692         const struct cred *cred = current_cred();
2693
2694         return dentry_has_perm(cred, dentry, FILE__READ);
2695 }
2696
2697 static noinline int audit_inode_permission(struct inode *inode,
2698                                            u32 perms, u32 audited, u32 denied,
2699                                            unsigned flags)
2700 {
2701         struct common_audit_data ad;
2702         struct inode_security_struct *isec = inode->i_security;
2703         int rc;
2704
2705         ad.type = LSM_AUDIT_DATA_INODE;
2706         ad.u.inode = inode;
2707
2708         rc = slow_avc_audit(current_sid(), isec->sid, isec->sclass, perms,
2709                             audited, denied, &ad, flags);
2710         if (rc)
2711                 return rc;
2712         return 0;
2713 }
2714
2715 static int selinux_inode_permission(struct inode *inode, int mask)
2716 {
2717         const struct cred *cred = current_cred();
2718         u32 perms;
2719         bool from_access;
2720         unsigned flags = mask & MAY_NOT_BLOCK;
2721         struct inode_security_struct *isec;
2722         u32 sid;
2723         struct av_decision avd;
2724         int rc, rc2;
2725         u32 audited, denied;
2726
2727         from_access = mask & MAY_ACCESS;
2728         mask &= (MAY_READ|MAY_WRITE|MAY_EXEC|MAY_APPEND);
2729
2730         /* No permission to check.  Existence test. */
2731         if (!mask)
2732                 return 0;
2733
2734         validate_creds(cred);
2735
2736         if (unlikely(IS_PRIVATE(inode)))
2737                 return 0;
2738
2739         perms = file_mask_to_av(inode->i_mode, mask);
2740
2741         sid = cred_sid(cred);
2742         isec = inode->i_security;
2743
2744         rc = avc_has_perm_noaudit(sid, isec->sid, isec->sclass, perms, 0, &avd);
2745         audited = avc_audit_required(perms, &avd, rc,
2746                                      from_access ? FILE__AUDIT_ACCESS : 0,
2747                                      &denied);
2748         if (likely(!audited))
2749                 return rc;
2750
2751         rc2 = audit_inode_permission(inode, perms, audited, denied, flags);
2752         if (rc2)
2753                 return rc2;
2754         return rc;
2755 }
2756
2757 static int selinux_inode_setattr(struct dentry *dentry, struct iattr *iattr)
2758 {
2759         const struct cred *cred = current_cred();
2760         unsigned int ia_valid = iattr->ia_valid;
2761         __u32 av = FILE__WRITE;
2762
2763         /* ATTR_FORCE is just used for ATTR_KILL_S[UG]ID. */
2764         if (ia_valid & ATTR_FORCE) {
2765                 ia_valid &= ~(ATTR_KILL_SUID | ATTR_KILL_SGID | ATTR_MODE |
2766                               ATTR_FORCE);
2767                 if (!ia_valid)
2768                         return 0;
2769         }
2770
2771         if (ia_valid & (ATTR_MODE | ATTR_UID | ATTR_GID |
2772                         ATTR_ATIME_SET | ATTR_MTIME_SET | ATTR_TIMES_SET))
2773                 return dentry_has_perm(cred, dentry, FILE__SETATTR);
2774
2775         if (selinux_policycap_openperm && (ia_valid & ATTR_SIZE))
2776                 av |= FILE__OPEN;
2777
2778         return dentry_has_perm(cred, dentry, av);
2779 }
2780
2781 static int selinux_inode_getattr(struct vfsmount *mnt, struct dentry *dentry)
2782 {
2783         const struct cred *cred = current_cred();
2784         struct path path;
2785
2786         path.dentry = dentry;
2787         path.mnt = mnt;
2788
2789         return path_has_perm(cred, &path, FILE__GETATTR);
2790 }
2791
2792 static int selinux_inode_setotherxattr(struct dentry *dentry, const char *name)
2793 {
2794         const struct cred *cred = current_cred();
2795
2796         if (!strncmp(name, XATTR_SECURITY_PREFIX,
2797                      sizeof XATTR_SECURITY_PREFIX - 1)) {
2798                 if (!strcmp(name, XATTR_NAME_CAPS)) {
2799                         if (!capable(CAP_SETFCAP))
2800                                 return -EPERM;
2801                 } else if (!capable(CAP_SYS_ADMIN)) {
2802                         /* A different attribute in the security namespace.
2803                            Restrict to administrator. */
2804                         return -EPERM;
2805                 }
2806         }
2807
2808         /* Not an attribute we recognize, so just check the
2809            ordinary setattr permission. */
2810         return dentry_has_perm(cred, dentry, FILE__SETATTR);
2811 }
2812
2813 static int selinux_inode_setxattr(struct dentry *dentry, const char *name,
2814                                   const void *value, size_t size, int flags)
2815 {
2816         struct inode *inode = dentry->d_inode;
2817         struct inode_security_struct *isec = inode->i_security;
2818         struct superblock_security_struct *sbsec;
2819         struct common_audit_data ad;
2820         u32 newsid, sid = current_sid();
2821         int rc = 0;
2822
2823         if (strcmp(name, XATTR_NAME_SELINUX))
2824                 return selinux_inode_setotherxattr(dentry, name);
2825
2826         sbsec = inode->i_sb->s_security;
2827         if (!(sbsec->flags & SE_SBLABELSUPP))
2828                 return -EOPNOTSUPP;
2829
2830         if (!inode_owner_or_capable(inode))
2831                 return -EPERM;
2832
2833         ad.type = LSM_AUDIT_DATA_DENTRY;
2834         ad.u.dentry = dentry;
2835
2836         rc = avc_has_perm(sid, isec->sid, isec->sclass,
2837                           FILE__RELABELFROM, &ad);
2838         if (rc)
2839                 return rc;
2840
2841         rc = security_context_to_sid(value, size, &newsid);
2842         if (rc == -EINVAL) {
2843                 if (!capable(CAP_MAC_ADMIN)) {
2844                         struct audit_buffer *ab;
2845                         size_t audit_size;
2846                         const char *str;
2847
2848                         /* We strip a nul only if it is at the end, otherwise the
2849                          * context contains a nul and we should audit that */
2850                         if (value) {
2851                                 str = value;
2852                                 if (str[size - 1] == '\0')
2853                                         audit_size = size - 1;
2854                                 else
2855                                         audit_size = size;
2856                         } else {
2857                                 str = "";
2858                                 audit_size = 0;
2859                         }
2860                         ab = audit_log_start(current->audit_context, GFP_ATOMIC, AUDIT_SELINUX_ERR);
2861                         audit_log_format(ab, "op=setxattr invalid_context=");
2862                         audit_log_n_untrustedstring(ab, value, audit_size);
2863                         audit_log_end(ab);
2864
2865                         return rc;
2866                 }
2867                 rc = security_context_to_sid_force(value, size, &newsid);
2868         }
2869         if (rc)
2870                 return rc;
2871
2872         rc = avc_has_perm(sid, newsid, isec->sclass,
2873                           FILE__RELABELTO, &ad);
2874         if (rc)
2875                 return rc;
2876
2877         rc = security_validate_transition(isec->sid, newsid, sid,
2878                                           isec->sclass);
2879         if (rc)
2880                 return rc;
2881
2882         return avc_has_perm(newsid,
2883                             sbsec->sid,
2884                             SECCLASS_FILESYSTEM,
2885                             FILESYSTEM__ASSOCIATE,
2886                             &ad);
2887 }
2888
2889 static void selinux_inode_post_setxattr(struct dentry *dentry, const char *name,
2890                                         const void *value, size_t size,
2891                                         int flags)
2892 {
2893         struct inode *inode = dentry->d_inode;
2894         struct inode_security_struct *isec = inode->i_security;
2895         u32 newsid;
2896         int rc;
2897
2898         if (strcmp(name, XATTR_NAME_SELINUX)) {
2899                 /* Not an attribute we recognize, so nothing to do. */
2900                 return;
2901         }
2902
2903         rc = security_context_to_sid_force(value, size, &newsid);
2904         if (rc) {
2905                 printk(KERN_ERR "SELinux:  unable to map context to SID"
2906                        "for (%s, %lu), rc=%d\n",
2907                        inode->i_sb->s_id, inode->i_ino, -rc);
2908                 return;
2909         }
2910
2911         isec->sclass = inode_mode_to_security_class(inode->i_mode);
2912         isec->sid = newsid;
2913         isec->initialized = 1;
2914
2915         return;
2916 }
2917
2918 static int selinux_inode_getxattr(struct dentry *dentry, const char *name)
2919 {
2920         const struct cred *cred = current_cred();
2921
2922         return dentry_has_perm(cred, dentry, FILE__GETATTR);
2923 }
2924
2925 static int selinux_inode_listxattr(struct dentry *dentry)
2926 {
2927         const struct cred *cred = current_cred();
2928
2929         return dentry_has_perm(cred, dentry, FILE__GETATTR);
2930 }
2931
2932 static int selinux_inode_removexattr(struct dentry *dentry, const char *name)
2933 {
2934         if (strcmp(name, XATTR_NAME_SELINUX))
2935                 return selinux_inode_setotherxattr(dentry, name);
2936
2937         /* No one is allowed to remove a SELinux security label.
2938            You can change the label, but all data must be labeled. */
2939         return -EACCES;
2940 }
2941
2942 /*
2943  * Copy the inode security context value to the user.
2944  *
2945  * Permission check is handled by selinux_inode_getxattr hook.
2946  */
2947 static int selinux_inode_getsecurity(const struct inode *inode, const char *name, void **buffer, bool alloc)
2948 {
2949         u32 size;
2950         int error;
2951         char *context = NULL;
2952         struct inode_security_struct *isec = inode->i_security;
2953
2954         if (strcmp(name, XATTR_SELINUX_SUFFIX))
2955                 return -EOPNOTSUPP;
2956
2957         /*
2958          * If the caller has CAP_MAC_ADMIN, then get the raw context
2959          * value even if it is not defined by current policy; otherwise,
2960          * use the in-core value under current policy.
2961          * Use the non-auditing forms of the permission checks since
2962          * getxattr may be called by unprivileged processes commonly
2963          * and lack of permission just means that we fall back to the
2964          * in-core context value, not a denial.
2965          */
2966         error = selinux_capable(current_cred(), &init_user_ns, CAP_MAC_ADMIN,
2967                                 SECURITY_CAP_NOAUDIT);
2968         if (!error)
2969                 error = security_sid_to_context_force(isec->sid, &context,
2970                                                       &size);
2971         else
2972                 error = security_sid_to_context(isec->sid, &context, &size);
2973         if (error)
2974                 return error;
2975         error = size;
2976         if (alloc) {
2977                 *buffer = context;
2978                 goto out_nofree;
2979         }
2980         kfree(context);
2981 out_nofree:
2982         return error;
2983 }
2984
2985 static int selinux_inode_setsecurity(struct inode *inode, const char *name,
2986                                      const void *value, size_t size, int flags)
2987 {
2988         struct inode_security_struct *isec = inode->i_security;
2989         u32 newsid;
2990         int rc;
2991
2992         if (strcmp(name, XATTR_SELINUX_SUFFIX))
2993                 return -EOPNOTSUPP;
2994
2995         if (!value || !size)
2996                 return -EACCES;
2997
2998         rc = security_context_to_sid((void *)value, size, &newsid);
2999         if (rc)
3000                 return rc;
3001
3002         isec->sclass = inode_mode_to_security_class(inode->i_mode);
3003         isec->sid = newsid;
3004         isec->initialized = 1;
3005         return 0;
3006 }
3007
3008 static int selinux_inode_listsecurity(struct inode *inode, char *buffer, size_t buffer_size)
3009 {
3010         const int len = sizeof(XATTR_NAME_SELINUX);
3011         if (buffer && len <= buffer_size)
3012                 memcpy(buffer, XATTR_NAME_SELINUX, len);
3013         return len;
3014 }
3015
3016 static void selinux_inode_getsecid(const struct inode *inode, u32 *secid)
3017 {
3018         struct inode_security_struct *isec = inode->i_security;
3019         *secid = isec->sid;
3020 }
3021
3022 /* file security operations */
3023
3024 static int selinux_revalidate_file_permission(struct file *file, int mask)
3025 {
3026         const struct cred *cred = current_cred();
3027         struct inode *inode = file_inode(file);
3028
3029         /* file_mask_to_av won't add FILE__WRITE if MAY_APPEND is set */
3030         if ((file->f_flags & O_APPEND) && (mask & MAY_WRITE))
3031                 mask |= MAY_APPEND;
3032
3033         return file_has_perm(cred, file,
3034                              file_mask_to_av(inode->i_mode, mask));
3035 }
3036
3037 static int selinux_file_permission(struct file *file, int mask)
3038 {
3039         struct inode *inode = file_inode(file);
3040         struct file_security_struct *fsec = file->f_security;
3041         struct inode_security_struct *isec = inode->i_security;
3042         u32 sid = current_sid();
3043
3044         if (!mask)
3045                 /* No permission to check.  Existence test. */
3046                 return 0;
3047
3048         if (sid == fsec->sid && fsec->isid == isec->sid &&
3049             fsec->pseqno == avc_policy_seqno())
3050                 /* No change since file_open check. */
3051                 return 0;
3052
3053         return selinux_revalidate_file_permission(file, mask);
3054 }
3055
3056 static int selinux_file_alloc_security(struct file *file)
3057 {
3058         return file_alloc_security(file);
3059 }
3060
3061 static void selinux_file_free_security(struct file *file)
3062 {
3063         file_free_security(file);
3064 }
3065
3066 static int selinux_file_ioctl(struct file *file, unsigned int cmd,
3067                               unsigned long arg)
3068 {
3069         const struct cred *cred = current_cred();
3070         int error = 0;
3071
3072         switch (cmd) {
3073         case FIONREAD:
3074         /* fall through */
3075         case FIBMAP:
3076         /* fall through */
3077         case FIGETBSZ:
3078         /* fall through */
3079         case FS_IOC_GETFLAGS:
3080         /* fall through */
3081         case FS_IOC_GETVERSION:
3082                 error = file_has_perm(cred, file, FILE__GETATTR);
3083                 break;
3084
3085         case FS_IOC_SETFLAGS:
3086         /* fall through */
3087         case FS_IOC_SETVERSION:
3088                 error = file_has_perm(cred, file, FILE__SETATTR);
3089                 break;
3090
3091         /* sys_ioctl() checks */
3092         case FIONBIO:
3093         /* fall through */
3094         case FIOASYNC:
3095                 error = file_has_perm(cred, file, 0);
3096                 break;
3097
3098         case KDSKBENT:
3099         case KDSKBSENT:
3100                 error = cred_has_capability(cred, CAP_SYS_TTY_CONFIG,
3101                                             SECURITY_CAP_AUDIT);
3102                 break;
3103
3104         /* default case assumes that the command will go
3105          * to the file's ioctl() function.
3106          */
3107         default:
3108                 error = file_has_perm(cred, file, FILE__IOCTL);
3109         }
3110         return error;
3111 }
3112
3113 static int default_noexec;
3114
3115 static int file_map_prot_check(struct file *file, unsigned long prot, int shared)
3116 {
3117         const struct cred *cred = current_cred();
3118         int rc = 0;
3119
3120         if (default_noexec &&
3121             (prot & PROT_EXEC) && (!file || (!shared && (prot & PROT_WRITE)))) {
3122                 /*
3123                  * We are making executable an anonymous mapping or a
3124                  * private file mapping that will also be writable.
3125                  * This has an additional check.
3126                  */
3127                 rc = cred_has_perm(cred, cred, PROCESS__EXECMEM);
3128                 if (rc)
3129                         goto error;
3130         }
3131
3132         if (file) {
3133                 /* read access is always possible with a mapping */
3134                 u32 av = FILE__READ;
3135
3136                 /* write access only matters if the mapping is shared */
3137                 if (shared && (prot & PROT_WRITE))
3138                         av |= FILE__WRITE;
3139
3140                 if (prot & PROT_EXEC)
3141                         av |= FILE__EXECUTE;
3142
3143                 return file_has_perm(cred, file, av);
3144         }
3145
3146 error:
3147         return rc;
3148 }
3149
3150 static int selinux_mmap_addr(unsigned long addr)
3151 {
3152         int rc = 0;
3153         u32 sid = current_sid();
3154
3155         /*
3156          * notice that we are intentionally putting the SELinux check before
3157          * the secondary cap_file_mmap check.  This is such a likely attempt
3158          * at bad behaviour/exploit that we always want to get the AVC, even
3159          * if DAC would have also denied the operation.
3160          */
3161         if (addr < CONFIG_LSM_MMAP_MIN_ADDR) {
3162                 rc = avc_has_perm(sid, sid, SECCLASS_MEMPROTECT,
3163                                   MEMPROTECT__MMAP_ZERO, NULL);
3164                 if (rc)
3165                         return rc;
3166         }
3167
3168         /* do DAC check on address space usage */
3169         return cap_mmap_addr(addr);
3170 }
3171
3172 static int selinux_mmap_file(struct file *file, unsigned long reqprot,
3173                              unsigned long prot, unsigned long flags)
3174 {
3175         if (selinux_checkreqprot)
3176                 prot = reqprot;
3177
3178         return file_map_prot_check(file, prot,
3179                                    (flags & MAP_TYPE) == MAP_SHARED);
3180 }
3181
3182 static int selinux_file_mprotect(struct vm_area_struct *vma,
3183                                  unsigned long reqprot,
3184                                  unsigned long prot)
3185 {
3186         const struct cred *cred = current_cred();
3187
3188         if (selinux_checkreqprot)
3189                 prot = reqprot;
3190
3191         if (default_noexec &&
3192             (prot & PROT_EXEC) && !(vma->vm_flags & VM_EXEC)) {
3193                 int rc = 0;
3194                 if (vma->vm_start >= vma->vm_mm->start_brk &&
3195                     vma->vm_end <= vma->vm_mm->brk) {
3196                         rc = cred_has_perm(cred, cred, PROCESS__EXECHEAP);
3197                 } else if (!vma->vm_file &&
3198                            vma->vm_start <= vma->vm_mm->start_stack &&
3199                            vma->vm_end >= vma->vm_mm->start_stack) {
3200                         rc = current_has_perm(current, PROCESS__EXECSTACK);
3201                 } else if (vma->vm_file && vma->anon_vma) {
3202                         /*
3203                          * We are making executable a file mapping that has
3204                          * had some COW done. Since pages might have been
3205                          * written, check ability to execute the possibly
3206                          * modified content.  This typically should only
3207                          * occur for text relocations.
3208                          */
3209                         rc = file_has_perm(cred, vma->vm_file, FILE__EXECMOD);
3210                 }
3211                 if (rc)
3212                         return rc;
3213         }
3214
3215         return file_map_prot_check(vma->vm_file, prot, vma->vm_flags&VM_SHARED);
3216 }
3217
3218 static int selinux_file_lock(struct file *file, unsigned int cmd)
3219 {
3220         const struct cred *cred = current_cred();
3221
3222         return file_has_perm(cred, file, FILE__LOCK);
3223 }
3224
3225 static int selinux_file_fcntl(struct file *file, unsigned int cmd,
3226                               unsigned long arg)
3227 {
3228         const struct cred *cred = current_cred();
3229         int err = 0;
3230
3231         switch (cmd) {
3232         case F_SETFL:
3233                 if ((file->f_flags & O_APPEND) && !(arg & O_APPEND)) {
3234                         err = file_has_perm(cred, file, FILE__WRITE);
3235                         break;
3236                 }
3237                 /* fall through */
3238         case F_SETOWN:
3239         case F_SETSIG:
3240         case F_GETFL:
3241         case F_GETOWN:
3242         case F_GETSIG:
3243         case F_GETOWNER_UIDS:
3244                 /* Just check FD__USE permission */
3245                 err = file_has_perm(cred, file, 0);
3246                 break;
3247         case F_GETLK:
3248         case F_SETLK:
3249         case F_SETLKW:
3250 #if BITS_PER_LONG == 32
3251         case F_GETLK64:
3252         case F_SETLK64:
3253         case F_SETLKW64:
3254 #endif
3255                 err = file_has_perm(cred, file, FILE__LOCK);
3256                 break;
3257         }
3258
3259         return err;
3260 }
3261
3262 static int selinux_file_set_fowner(struct file *file)
3263 {
3264         struct file_security_struct *fsec;
3265
3266         fsec = file->f_security;
3267         fsec->fown_sid = current_sid();
3268
3269         return 0;
3270 }
3271
3272 static int selinux_file_send_sigiotask(struct task_struct *tsk,
3273                                        struct fown_struct *fown, int signum)
3274 {
3275         struct file *file;
3276         u32 sid = task_sid(tsk);
3277         u32 perm;
3278         struct file_security_struct *fsec;
3279
3280         /* struct fown_struct is never outside the context of a struct file */
3281         file = container_of(fown, struct file, f_owner);
3282
3283         fsec = file->f_security;
3284
3285         if (!signum)
3286                 perm = signal_to_av(SIGIO); /* as per send_sigio_to_task */
3287         else
3288                 perm = signal_to_av(signum);
3289
3290         return avc_has_perm(fsec->fown_sid, sid,
3291                             SECCLASS_PROCESS, perm, NULL);
3292 }
3293
3294 static int selinux_file_receive(struct file *file)
3295 {
3296         const struct cred *cred = current_cred();
3297
3298         return file_has_perm(cred, file, file_to_av(file));
3299 }
3300
3301 static int selinux_file_open(struct file *file, const struct cred *cred)
3302 {
3303         struct file_security_struct *fsec;
3304         struct inode_security_struct *isec;
3305
3306         fsec = file->f_security;
3307         isec = file_inode(file)->i_security;
3308         /*
3309          * Save inode label and policy sequence number
3310          * at open-time so that selinux_file_permission
3311          * can determine whether revalidation is necessary.
3312          * Task label is already saved in the file security
3313          * struct as its SID.
3314          */
3315         fsec->isid = isec->sid;
3316         fsec->pseqno = avc_policy_seqno();
3317         /*
3318          * Since the inode label or policy seqno may have changed
3319          * between the selinux_inode_permission check and the saving
3320          * of state above, recheck that access is still permitted.
3321          * Otherwise, access might never be revalidated against the
3322          * new inode label or new policy.
3323          * This check is not redundant - do not remove.
3324          */
3325         return path_has_perm(cred, &file->f_path, open_file_to_av(file));
3326 }
3327
3328 /* task security operations */
3329
3330 static int selinux_task_create(unsigned long clone_flags)
3331 {
3332         return current_has_perm(current, PROCESS__FORK);
3333 }
3334
3335 /*
3336  * allocate the SELinux part of blank credentials
3337  */
3338 static int selinux_cred_alloc_blank(struct cred *cred, gfp_t gfp)
3339 {
3340         struct task_security_struct *tsec;
3341
3342         tsec = kzalloc(sizeof(struct task_security_struct), gfp);
3343         if (!tsec)
3344                 return -ENOMEM;
3345
3346         cred->security = tsec;
3347         return 0;
3348 }
3349
3350 /*
3351  * detach and free the LSM part of a set of credentials
3352  */
3353 static void selinux_cred_free(struct cred *cred)
3354 {
3355         struct task_security_struct *tsec = cred->security;
3356
3357         /*
3358          * cred->security == NULL if security_cred_alloc_blank() or
3359          * security_prepare_creds() returned an error.
3360          */
3361         BUG_ON(cred->security && (unsigned long) cred->security < PAGE_SIZE);
3362         cred->security = (void *) 0x7UL;
3363         kfree(tsec);
3364 }
3365
3366 /*
3367  * prepare a new set of credentials for modification
3368  */
3369 static int selinux_cred_prepare(struct cred *new, const struct cred *old,
3370                                 gfp_t gfp)
3371 {
3372         const struct task_security_struct *old_tsec;
3373         struct task_security_struct *tsec;
3374
3375         old_tsec = old->security;
3376
3377         tsec = kmemdup(old_tsec, sizeof(struct task_security_struct), gfp);
3378         if (!tsec)
3379                 return -ENOMEM;
3380
3381         new->security = tsec;
3382         return 0;
3383 }
3384
3385 /*
3386  * transfer the SELinux data to a blank set of creds
3387  */
3388 static void selinux_cred_transfer(struct cred *new, const struct cred *old)
3389 {
3390         const struct task_security_struct *old_tsec = old->security;
3391         struct task_security_struct *tsec = new->security;
3392
3393         *tsec = *old_tsec;
3394 }
3395
3396 /*
3397  * set the security data for a kernel service
3398  * - all the creation contexts are set to unlabelled
3399  */
3400 static int selinux_kernel_act_as(struct cred *new, u32 secid)
3401 {
3402         struct task_security_struct *tsec = new->security;
3403         u32 sid = current_sid();
3404         int ret;
3405
3406         ret = avc_has_perm(sid, secid,
3407                            SECCLASS_KERNEL_SERVICE,
3408                            KERNEL_SERVICE__USE_AS_OVERRIDE,
3409                            NULL);
3410         if (ret == 0) {
3411                 tsec->sid = secid;
3412                 tsec->create_sid = 0;
3413                 tsec->keycreate_sid = 0;
3414                 tsec->sockcreate_sid = 0;
3415         }
3416         return ret;
3417 }
3418
3419 /*
3420  * set the file creation context in a security record to the same as the
3421  * objective context of the specified inode
3422  */
3423 static int selinux_kernel_create_files_as(struct cred *new, struct inode *inode)
3424 {
3425         struct inode_security_struct *isec = inode->i_security;
3426         struct task_security_struct *tsec = new->security;
3427         u32 sid = current_sid();
3428         int ret;
3429
3430         ret = avc_has_perm(sid, isec->sid,
3431                            SECCLASS_KERNEL_SERVICE,
3432                            KERNEL_SERVICE__CREATE_FILES_AS,
3433                            NULL);
3434
3435         if (ret == 0)
3436                 tsec->create_sid = isec->sid;
3437         return ret;
3438 }
3439
3440 static int selinux_kernel_module_request(char *kmod_name)
3441 {
3442         u32 sid;
3443         struct common_audit_data ad;
3444
3445         sid = task_sid(current);
3446
3447         ad.type = LSM_AUDIT_DATA_KMOD;
3448         ad.u.kmod_name = kmod_name;
3449
3450         return avc_has_perm(sid, SECINITSID_KERNEL, SECCLASS_SYSTEM,
3451                             SYSTEM__MODULE_REQUEST, &ad);
3452 }
3453
3454 static int selinux_task_setpgid(struct task_struct *p, pid_t pgid)
3455 {
3456         return current_has_perm(p, PROCESS__SETPGID);
3457 }
3458
3459 static int selinux_task_getpgid(struct task_struct *p)
3460 {
3461         return current_has_perm(p, PROCESS__GETPGID);
3462 }
3463
3464 static int selinux_task_getsid(struct task_struct *p)
3465 {
3466         return current_has_perm(p, PROCESS__GETSESSION);
3467 }
3468
3469 static void selinux_task_getsecid(struct task_struct *p, u32 *secid)
3470 {
3471         *secid = task_sid(p);
3472 }
3473
3474 static int selinux_task_setnice(struct task_struct *p, int nice)
3475 {
3476         int rc;
3477
3478         rc = cap_task_setnice(p, nice);
3479         if (rc)
3480                 return rc;
3481
3482         return current_has_perm(p, PROCESS__SETSCHED);
3483 }
3484
3485 static int selinux_task_setioprio(struct task_struct *p, int ioprio)
3486 {
3487         int rc;
3488
3489         rc = cap_task_setioprio(p, ioprio);
3490         if (rc)
3491                 return rc;
3492
3493         return current_has_perm(p, PROCESS__SETSCHED);
3494 }
3495
3496 static int selinux_task_getioprio(struct task_struct *p)
3497 {
3498         return current_has_perm(p, PROCESS__GETSCHED);
3499 }
3500
3501 static int selinux_task_setrlimit(struct task_struct *p, unsigned int resource,
3502                 struct rlimit *new_rlim)
3503 {
3504         struct rlimit *old_rlim = p->signal->rlim + resource;
3505
3506         /* Control the ability to change the hard limit (whether
3507            lowering or raising it), so that the hard limit can
3508            later be used as a safe reset point for the soft limit
3509            upon context transitions.  See selinux_bprm_committing_creds. */
3510         if (old_rlim->rlim_max != new_rlim->rlim_max)
3511                 return current_has_perm(p, PROCESS__SETRLIMIT);
3512
3513         return 0;
3514 }
3515
3516 static int selinux_task_setscheduler(struct task_struct *p)
3517 {
3518         int rc;
3519
3520         rc = cap_task_setscheduler(p);
3521         if (rc)
3522                 return rc;
3523
3524         return current_has_perm(p, PROCESS__SETSCHED);
3525 }
3526
3527 static int selinux_task_getscheduler(struct task_struct *p)
3528 {
3529         return current_has_perm(p, PROCESS__GETSCHED);
3530 }
3531
3532 static int selinux_task_movememory(struct task_struct *p)
3533 {
3534         return current_has_perm(p, PROCESS__SETSCHED);
3535 }
3536
3537 static int selinux_task_kill(struct task_struct *p, struct siginfo *info,
3538                                 int sig, u32 secid)
3539 {
3540         u32 perm;
3541         int rc;
3542
3543         if (!sig)
3544                 perm = PROCESS__SIGNULL; /* null signal; existence test */
3545         else
3546                 perm = signal_to_av(sig);
3547         if (secid)
3548                 rc = avc_has_perm(secid, task_sid(p),
3549                                   SECCLASS_PROCESS, perm, NULL);
3550         else
3551                 rc = current_has_perm(p, perm);
3552         return rc;
3553 }
3554
3555 static int selinux_task_wait(struct task_struct *p)
3556 {
3557         return task_has_perm(p, current, PROCESS__SIGCHLD);
3558 }
3559
3560 static void selinux_task_to_inode(struct task_struct *p,
3561                                   struct inode *inode)
3562 {
3563         struct inode_security_struct *isec = inode->i_security;
3564         u32 sid = task_sid(p);
3565
3566         isec->sid = sid;
3567         isec->initialized = 1;
3568 }
3569
3570 /* Returns error only if unable to parse addresses */
3571 static int selinux_parse_skb_ipv4(struct sk_buff *skb,
3572                         struct common_audit_data *ad, u8 *proto)
3573 {
3574         int offset, ihlen, ret = -EINVAL;
3575         struct iphdr _iph, *ih;
3576
3577         offset = skb_network_offset(skb);
3578         ih = skb_header_pointer(skb, offset, sizeof(_iph), &_iph);
3579         if (ih == NULL)
3580                 goto out;
3581
3582         ihlen = ih->ihl * 4;
3583         if (ihlen < sizeof(_iph))
3584                 goto out;
3585
3586         ad->u.net->v4info.saddr = ih->saddr;
3587         ad->u.net->v4info.daddr = ih->daddr;
3588         ret = 0;
3589
3590         if (proto)
3591                 *proto = ih->protocol;
3592
3593         switch (ih->protocol) {
3594         case IPPROTO_TCP: {
3595                 struct tcphdr _tcph, *th;
3596
3597                 if (ntohs(ih->frag_off) & IP_OFFSET)
3598                         break;
3599
3600                 offset += ihlen;
3601                 th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph);
3602                 if (th == NULL)
3603                         break;
3604
3605                 ad->u.net->sport = th->source;
3606                 ad->u.net->dport = th->dest;
3607                 break;
3608         }
3609
3610         case IPPROTO_UDP: {
3611                 struct udphdr _udph, *uh;
3612
3613                 if (ntohs(ih->frag_off) & IP_OFFSET)
3614                         break;
3615
3616                 offset += ihlen;
3617                 uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph);
3618                 if (uh == NULL)
3619                         break;
3620
3621                 ad->u.net->sport = uh->source;
3622                 ad->u.net->dport = uh->dest;
3623                 break;
3624         }
3625
3626         case IPPROTO_DCCP: {
3627                 struct dccp_hdr _dccph, *dh;
3628
3629                 if (ntohs(ih->frag_off) & IP_OFFSET)
3630                         break;
3631
3632                 offset += ihlen;
3633                 dh = skb_header_pointer(skb, offset, sizeof(_dccph), &_dccph);
3634                 if (dh == NULL)
3635                         break;
3636
3637                 ad->u.net->sport = dh->dccph_sport;
3638                 ad->u.net->dport = dh->dccph_dport;
3639                 break;
3640         }
3641
3642         default:
3643                 break;
3644         }
3645 out:
3646         return ret;
3647 }
3648
3649 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
3650
3651 /* Returns error only if unable to parse addresses */
3652 static int selinux_parse_skb_ipv6(struct sk_buff *skb,
3653                         struct common_audit_data *ad, u8 *proto)
3654 {
3655         u8 nexthdr;
3656         int ret = -EINVAL, offset;
3657         struct ipv6hdr _ipv6h, *ip6;
3658         __be16 frag_off;
3659
3660         offset = skb_network_offset(skb);
3661         ip6 = skb_header_pointer(skb, offset, sizeof(_ipv6h), &_ipv6h);
3662         if (ip6 == NULL)
3663                 goto out;
3664
3665         ad->u.net->v6info.saddr = ip6->saddr;
3666         ad->u.net->v6info.daddr = ip6->daddr;
3667         ret = 0;
3668
3669         nexthdr = ip6->nexthdr;
3670         offset += sizeof(_ipv6h);
3671         offset = ipv6_skip_exthdr(skb, offset, &nexthdr, &frag_off);
3672         if (offset < 0)
3673                 goto out;
3674
3675         if (proto)
3676                 *proto = nexthdr;
3677
3678         switch (nexthdr) {
3679         case IPPROTO_TCP: {
3680                 struct tcphdr _tcph, *th;
3681
3682                 th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph);
3683                 if (th == NULL)
3684                         break;
3685
3686                 ad->u.net->sport = th->source;
3687                 ad->u.net->dport = th->dest;
3688                 break;
3689         }
3690
3691         case IPPROTO_UDP: {
3692                 struct udphdr _udph, *uh;
3693
3694                 uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph);
3695                 if (uh == NULL)
3696                         break;
3697
3698                 ad->u.net->sport = uh->source;
3699                 ad->u.net->dport = uh->dest;
3700                 break;
3701         }
3702
3703         case IPPROTO_DCCP: {
3704                 struct dccp_hdr _dccph, *dh;
3705
3706                 dh = skb_header_pointer(skb, offset, sizeof(_dccph), &_dccph);
3707                 if (dh == NULL)
3708                         break;
3709
3710                 ad->u.net->sport = dh->dccph_sport;
3711                 ad->u.net->dport = dh->dccph_dport;
3712                 break;
3713         }
3714
3715         /* includes fragments */
3716         default:
3717                 break;
3718         }
3719 out:
3720         return ret;
3721 }
3722
3723 #endif /* IPV6 */
3724
3725 static int selinux_parse_skb(struct sk_buff *skb, struct common_audit_data *ad,
3726                              char **_addrp, int src, u8 *proto)
3727 {
3728         char *addrp;
3729         int ret;
3730
3731         switch (ad->u.net->family) {
3732         case PF_INET:
3733                 ret = selinux_parse_skb_ipv4(skb, ad, proto);
3734                 if (ret)
3735                         goto parse_error;
3736                 addrp = (char *)(src ? &ad->u.net->v4info.saddr :
3737                                        &ad->u.net->v4info.daddr);
3738                 goto okay;
3739
3740 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
3741         case PF_INET6:
3742                 ret = selinux_parse_skb_ipv6(skb, ad, proto);
3743                 if (ret)
3744                         goto parse_error;
3745                 addrp = (char *)(src ? &ad->u.net->v6info.saddr :
3746                                        &ad->u.net->v6info.daddr);
3747                 goto okay;
3748 #endif  /* IPV6 */
3749         default:
3750                 addrp = NULL;
3751                 goto okay;
3752         }
3753
3754 parse_error:
3755         printk(KERN_WARNING
3756                "SELinux: failure in selinux_parse_skb(),"
3757                " unable to parse packet\n");
3758         return ret;
3759
3760 okay:
3761         if (_addrp)
3762                 *_addrp = addrp;
3763         return 0;
3764 }
3765
3766 /**
3767  * selinux_skb_peerlbl_sid - Determine the peer label of a packet
3768  * @skb: the packet
3769  * @family: protocol family
3770  * @sid: the packet's peer label SID
3771  *
3772  * Description:
3773  * Check the various different forms of network peer labeling and determine
3774  * the peer label/SID for the packet; most of the magic actually occurs in
3775  * the security server function security_net_peersid_cmp().  The function
3776  * returns zero if the value in @sid is valid (although it may be SECSID_NULL)
3777  * or -EACCES if @sid is invalid due to inconsistencies with the different
3778  * peer labels.
3779  *
3780  */
3781 static int selinux_skb_peerlbl_sid(struct sk_buff *skb, u16 family, u32 *sid)
3782 {
3783         int err;
3784         u32 xfrm_sid;
3785         u32 nlbl_sid;
3786         u32 nlbl_type;
3787
3788         selinux_skb_xfrm_sid(skb, &xfrm_sid);
3789         selinux_netlbl_skbuff_getsid(skb, family, &nlbl_type, &nlbl_sid);
3790
3791         err = security_net_peersid_resolve(nlbl_sid, nlbl_type, xfrm_sid, sid);
3792         if (unlikely(err)) {
3793                 printk(KERN_WARNING
3794                        "SELinux: failure in selinux_skb_peerlbl_sid(),"
3795                        " unable to determine packet's peer label\n");
3796                 return -EACCES;
3797         }
3798
3799         return 0;
3800 }
3801
3802 /* socket security operations */
3803
3804 static int socket_sockcreate_sid(const struct task_security_struct *tsec,
3805                                  u16 secclass, u32 *socksid)
3806 {
3807         if (tsec->sockcreate_sid > SECSID_NULL) {
3808                 *socksid = tsec->sockcreate_sid;
3809                 return 0;
3810         }
3811
3812         return security_transition_sid(tsec->sid, tsec->sid, secclass, NULL,
3813                                        socksid);
3814 }
3815
3816 static int sock_has_perm(struct task_struct *task, struct sock *sk, u32 perms)
3817 {
3818         struct sk_security_struct *sksec = sk->sk_security;
3819         struct common_audit_data ad;
3820         struct lsm_network_audit net = {0,};
3821         u32 tsid = task_sid(task);
3822
3823         if (sksec->sid == SECINITSID_KERNEL)
3824                 return 0;
3825
3826         ad.type = LSM_AUDIT_DATA_NET;
3827         ad.u.net = &net;
3828         ad.u.net->sk = sk;
3829
3830         return avc_has_perm(tsid, sksec->sid, sksec->sclass, perms, &ad);
3831 }
3832
3833 static int selinux_socket_create(int family, int type,
3834                                  int protocol, int kern)
3835 {
3836         const struct task_security_struct *tsec = current_security();
3837         u32 newsid;
3838         u16 secclass;
3839         int rc;
3840
3841         if (kern)
3842                 return 0;
3843
3844         secclass = socket_type_to_security_class(family, type, protocol);
3845         rc = socket_sockcreate_sid(tsec, secclass, &newsid);
3846         if (rc)
3847                 return rc;
3848
3849         return avc_has_perm(tsec->sid, newsid, secclass, SOCKET__CREATE, NULL);
3850 }
3851
3852 static int selinux_socket_post_create(struct socket *sock, int family,
3853                                       int type, int protocol, int kern)
3854 {
3855         const struct task_security_struct *tsec = current_security();
3856         struct inode_security_struct *isec = SOCK_INODE(sock)->i_security;
3857         struct sk_security_struct *sksec;
3858         int err = 0;
3859
3860         isec->sclass = socket_type_to_security_class(family, type, protocol);
3861
3862         if (kern)
3863                 isec->sid = SECINITSID_KERNEL;
3864         else {
3865                 err = socket_sockcreate_sid(tsec, isec->sclass, &(isec->sid));
3866                 if (err)
3867                         return err;
3868         }
3869
3870         isec->initialized = 1;
3871
3872         if (sock->sk) {
3873                 sksec = sock->sk->sk_security;
3874                 sksec->sid = isec->sid;
3875                 sksec->sclass = isec->sclass;
3876                 err = selinux_netlbl_socket_post_create(sock->sk, family);
3877         }
3878
3879         return err;
3880 }
3881
3882 /* Range of port numbers used to automatically bind.
3883    Need to determine whether we should perform a name_bind
3884    permission check between the socket and the port number. */
3885
3886 static int selinux_socket_bind(struct socket *sock, struct sockaddr *address, int addrlen)
3887 {
3888         struct sock *sk = sock->sk;
3889         u16 family;
3890         int err;
3891
3892         err = sock_has_perm(current, sk, SOCKET__BIND);
3893         if (err)
3894                 goto out;
3895
3896         /*
3897          * If PF_INET or PF_INET6, check name_bind permission for the port.
3898          * Multiple address binding for SCTP is not supported yet: we just
3899          * check the first address now.
3900          */
3901         family = sk->sk_family;
3902         if (family == PF_INET || family == PF_INET6) {
3903                 char *addrp;
3904                 struct sk_security_struct *sksec = sk->sk_security;
3905                 struct common_audit_data ad;
3906                 struct lsm_network_audit net = {0,};
3907                 struct sockaddr_in *addr4 = NULL;
3908                 struct sockaddr_in6 *addr6 = NULL;
3909                 unsigned short snum;
3910                 u32 sid, node_perm;
3911
3912                 if (family == PF_INET) {
3913                         addr4 = (struct sockaddr_in *)address;
3914                         snum = ntohs(addr4->sin_port);
3915                         addrp = (char *)&addr4->sin_addr.s_addr;
3916                 } else {
3917                         addr6 = (struct sockaddr_in6 *)address;
3918                         snum = ntohs(addr6->sin6_port);
3919                         addrp = (char *)&addr6->sin6_addr.s6_addr;
3920                 }
3921
3922                 if (snum) {
3923                         int low, high;
3924
3925                         inet_get_local_port_range(&low, &high);
3926
3927                         if (snum < max(PROT_SOCK, low) || snum > high) {
3928                                 err = sel_netport_sid(sk->sk_protocol,
3929                                                       snum, &sid);
3930                                 if (err)
3931                                         goto out;
3932                                 ad.type = LSM_AUDIT_DATA_NET;
3933                                 ad.u.net = &net;
3934                                 ad.u.net->sport = htons(snum);
3935                                 ad.u.net->family = family;
3936                                 err = avc_has_perm(sksec->sid, sid,
3937                                                    sksec->sclass,
3938                                                    SOCKET__NAME_BIND, &ad);
3939                                 if (err)
3940                                         goto out;
3941                         }
3942                 }
3943
3944                 switch (sksec->sclass) {
3945                 case SECCLASS_TCP_SOCKET:
3946                         node_perm = TCP_SOCKET__NODE_BIND;
3947                         break;
3948
3949                 case SECCLASS_UDP_SOCKET:
3950                         node_perm = UDP_SOCKET__NODE_BIND;
3951                         break;
3952
3953                 case SECCLASS_DCCP_SOCKET:
3954                         node_perm = DCCP_SOCKET__NODE_BIND;
3955                         break;
3956
3957                 default:
3958                         node_perm = RAWIP_SOCKET__NODE_BIND;
3959                         break;
3960                 }
3961
3962                 err = sel_netnode_sid(addrp, family, &sid);
3963                 if (err)
3964                         goto out;
3965
3966                 ad.type = LSM_AUDIT_DATA_NET;
3967                 ad.u.net = &net;
3968                 ad.u.net->sport = htons(snum);
3969                 ad.u.net->family = family;
3970
3971                 if (family == PF_INET)
3972                         ad.u.net->v4info.saddr = addr4->sin_addr.s_addr;
3973                 else
3974                         ad.u.net->v6info.saddr = addr6->sin6_addr;
3975
3976                 err = avc_has_perm(sksec->sid, sid,
3977                                    sksec->sclass, node_perm, &ad);
3978                 if (err)
3979                         goto out;
3980         }
3981 out:
3982         return err;
3983 }
3984
3985 static int selinux_socket_connect(struct socket *sock, struct sockaddr *address, int addrlen)
3986 {
3987         struct sock *sk = sock->sk;
3988         struct sk_security_struct *sksec = sk->sk_security;
3989         int err;
3990
3991         err = sock_has_perm(current, sk, SOCKET__CONNECT);
3992         if (err)
3993                 return err;
3994
3995         /*
3996          * If a TCP or DCCP socket, check name_connect permission for the port.
3997          */
3998         if (sksec->sclass == SECCLASS_TCP_SOCKET ||
3999             sksec->sclass == SECCLASS_DCCP_SOCKET) {
4000                 struct common_audit_data ad;
4001                 struct lsm_network_audit net = {0,};
4002                 struct sockaddr_in *addr4 = NULL;
4003                 struct sockaddr_in6 *addr6 = NULL;
4004                 unsigned short snum;
4005                 u32 sid, perm;
4006
4007                 if (sk->sk_family == PF_INET) {
4008                         addr4 = (struct sockaddr_in *)address;
4009                         if (addrlen < sizeof(struct sockaddr_in))
4010                                 return -EINVAL;
4011                         snum = ntohs(addr4->sin_port);
4012                 } else {
4013                         addr6 = (struct sockaddr_in6 *)address;
4014                         if (addrlen < SIN6_LEN_RFC2133)
4015                                 return -EINVAL;
4016                         snum = ntohs(addr6->sin6_port);
4017                 }
4018
4019                 err = sel_netport_sid(sk->sk_protocol, snum, &sid);
4020                 if (err)
4021                         goto out;
4022
4023                 perm = (sksec->sclass == SECCLASS_TCP_SOCKET) ?
4024                        TCP_SOCKET__NAME_CONNECT : DCCP_SOCKET__NAME_CONNECT;
4025
4026                 ad.type = LSM_AUDIT_DATA_NET;
4027                 ad.u.net = &net;
4028                 ad.u.net->dport = htons(snum);
4029                 ad.u.net->family = sk->sk_family;
4030                 err = avc_has_perm(sksec->sid, sid, sksec->sclass, perm, &ad);
4031                 if (err)
4032                         goto out;
4033         }
4034
4035         err = selinux_netlbl_socket_connect(sk, address);
4036
4037 out:
4038         return err;
4039 }
4040
4041 static int selinux_socket_listen(struct socket *sock, int backlog)
4042 {
4043         return sock_has_perm(current, sock->sk, SOCKET__LISTEN);
4044 }
4045
4046 static int selinux_socket_accept(struct socket *sock, struct socket *newsock)
4047 {
4048         int err;
4049         struct inode_security_struct *isec;
4050         struct inode_security_struct *newisec;
4051
4052         err = sock_has_perm(current, sock->sk, SOCKET__ACCEPT);
4053         if (err)
4054                 return err;
4055
4056         newisec = SOCK_INODE(newsock)->i_security;
4057
4058         isec = SOCK_INODE(sock)->i_security;
4059         newisec->sclass = isec->sclass;
4060         newisec->sid = isec->sid;
4061         newisec->initialized = 1;
4062
4063         return 0;
4064 }
4065
4066 static int selinux_socket_sendmsg(struct socket *sock, struct msghdr *msg,
4067                                   int size)
4068 {
4069         return sock_has_perm(current, sock->sk, SOCKET__WRITE);
4070 }
4071
4072 static int selinux_socket_recvmsg(struct socket *sock, struct msghdr *msg,
4073                                   int size, int flags)
4074 {
4075         return sock_has_perm(current, sock->sk, SOCKET__READ);
4076 }
4077
4078 static int selinux_socket_getsockname(struct socket *sock)
4079 {
4080         return sock_has_perm(current, sock->sk, SOCKET__GETATTR);
4081 }
4082
4083 static int selinux_socket_getpeername(struct socket *sock)
4084 {
4085         return sock_has_perm(current, sock->sk, SOCKET__GETATTR);
4086 }
4087
4088 static int selinux_socket_setsockopt(struct socket *sock, int level, int optname)
4089 {
4090         int err;
4091
4092         err = sock_has_perm(current, sock->sk, SOCKET__SETOPT);
4093         if (err)
4094                 return err;
4095
4096         return selinux_netlbl_socket_setsockopt(sock, level, optname);
4097 }
4098
4099 static int selinux_socket_getsockopt(struct socket *sock, int level,
4100                                      int optname)
4101 {
4102         return sock_has_perm(current, sock->sk, SOCKET__GETOPT);
4103 }
4104
4105 static int selinux_socket_shutdown(struct socket *sock, int how)
4106 {
4107         return sock_has_perm(current, sock->sk, SOCKET__SHUTDOWN);
4108 }
4109
4110 static int selinux_socket_unix_stream_connect(struct sock *sock,
4111                                               struct sock *other,
4112                                               struct sock *newsk)
4113 {
4114         struct sk_security_struct *sksec_sock = sock->sk_security;
4115         struct sk_security_struct *sksec_other = other->sk_security;
4116         struct sk_security_struct *sksec_new = newsk->sk_security;
4117         struct common_audit_data ad;
4118         struct lsm_network_audit net = {0,};
4119         int err;
4120
4121         ad.type = LSM_AUDIT_DATA_NET;
4122         ad.u.net = &net;
4123         ad.u.net->sk = other;
4124
4125         err = avc_has_perm(sksec_sock->sid, sksec_other->sid,
4126                            sksec_other->sclass,
4127                            UNIX_STREAM_SOCKET__CONNECTTO, &ad);
4128         if (err)
4129                 return err;
4130
4131         /* server child socket */
4132         sksec_new->peer_sid = sksec_sock->sid;
4133         err = security_sid_mls_copy(sksec_other->sid, sksec_sock->sid,
4134                                     &sksec_new->sid);
4135         if (err)
4136                 return err;
4137
4138         /* connecting socket */
4139         sksec_sock->peer_sid = sksec_new->sid;
4140
4141         return 0;
4142 }
4143
4144 static int selinux_socket_unix_may_send(struct socket *sock,
4145                                         struct socket *other)
4146 {
4147         struct sk_security_struct *ssec = sock->sk->sk_security;
4148         struct sk_security_struct *osec = other->sk->sk_security;
4149         struct common_audit_data ad;
4150         struct lsm_network_audit net = {0,};
4151
4152         ad.type = LSM_AUDIT_DATA_NET;
4153         ad.u.net = &net;
4154         ad.u.net->sk = other->sk;
4155
4156         return avc_has_perm(ssec->sid, osec->sid, osec->sclass, SOCKET__SENDTO,
4157                             &ad);
4158 }
4159
4160 static int selinux_inet_sys_rcv_skb(int ifindex, char *addrp, u16 family,
4161                                     u32 peer_sid,
4162                                     struct common_audit_data *ad)
4163 {
4164         int err;
4165         u32 if_sid;
4166         u32 node_sid;
4167
4168         err = sel_netif_sid(ifindex, &if_sid);
4169         if (err)
4170                 return err;
4171         err = avc_has_perm(peer_sid, if_sid,
4172                            SECCLASS_NETIF, NETIF__INGRESS, ad);
4173         if (err)
4174                 return err;
4175
4176         err = sel_netnode_sid(addrp, family, &node_sid);
4177         if (err)
4178                 return err;
4179         return avc_has_perm(peer_sid, node_sid,
4180                             SECCLASS_NODE, NODE__RECVFROM, ad);
4181 }
4182
4183 static int selinux_sock_rcv_skb_compat(struct sock *sk, struct sk_buff *skb,
4184                                        u16 family)
4185 {
4186         int err = 0;
4187         struct sk_security_struct *sksec = sk->sk_security;
4188         u32 sk_sid = sksec->sid;
4189         struct common_audit_data ad;
4190         struct lsm_network_audit net = {0,};
4191         char *addrp;
4192
4193         ad.type = LSM_AUDIT_DATA_NET;
4194         ad.u.net = &net;
4195         ad.u.net->netif = skb->skb_iif;
4196         ad.u.net->family = family;
4197         err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL);
4198         if (err)
4199                 return err;
4200
4201         if (selinux_secmark_enabled()) {
4202                 err = avc_has_perm(sk_sid, skb->secmark, SECCLASS_PACKET,
4203                                    PACKET__RECV, &ad);
4204                 if (err)
4205                         return err;
4206         }
4207
4208         err = selinux_netlbl_sock_rcv_skb(sksec, skb, family, &ad);
4209         if (err)
4210                 return err;
4211         err = selinux_xfrm_sock_rcv_skb(sksec->sid, skb, &ad);
4212
4213         return err;
4214 }
4215
4216 static int selinux_socket_sock_rcv_skb(struct sock *sk, struct sk_buff *skb)
4217 {
4218         int err;
4219         struct sk_security_struct *sksec = sk->sk_security;
4220         u16 family = sk->sk_family;
4221         u32 sk_sid = sksec->sid;
4222         struct common_audit_data ad;
4223         struct lsm_network_audit net = {0,};
4224         char *addrp;
4225         u8 secmark_active;
4226         u8 peerlbl_active;
4227
4228         if (family != PF_INET && family != PF_INET6)
4229                 return 0;
4230
4231         /* Handle mapped IPv4 packets arriving via IPv6 sockets */
4232         if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
4233                 family = PF_INET;
4234
4235         /* If any sort of compatibility mode is enabled then handoff processing
4236          * to the selinux_sock_rcv_skb_compat() function to deal with the
4237          * special handling.  We do this in an attempt to keep this function
4238          * as fast and as clean as possible. */
4239         if (!selinux_policycap_netpeer)
4240                 return selinux_sock_rcv_skb_compat(sk, skb, family);
4241
4242         secmark_active = selinux_secmark_enabled();
4243         peerlbl_active = netlbl_enabled() || selinux_xfrm_enabled();
4244         if (!secmark_active && !peerlbl_active)
4245                 return 0;
4246
4247         ad.type = LSM_AUDIT_DATA_NET;
4248         ad.u.net = &net;
4249         ad.u.net->netif = skb->skb_iif;
4250         ad.u.net->family = family;
4251         err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL);
4252         if (err)
4253                 return err;
4254
4255         if (peerlbl_active) {
4256                 u32 peer_sid;
4257
4258                 err = selinux_skb_peerlbl_sid(skb, family, &peer_sid);
4259                 if (err)
4260                         return err;
4261                 err = selinux_inet_sys_rcv_skb(skb->skb_iif, addrp, family,
4262                                                peer_sid, &ad);
4263                 if (err) {
4264                         selinux_netlbl_err(skb, err, 0);
4265                         return err;
4266                 }
4267                 err = avc_has_perm(sk_sid, peer_sid, SECCLASS_PEER,
4268                                    PEER__RECV, &ad);
4269                 if (err)
4270                         selinux_netlbl_err(skb, err, 0);
4271         }
4272
4273         if (secmark_active) {
4274                 err = avc_has_perm(sk_sid, skb->secmark, SECCLASS_PACKET,
4275                                    PACKET__RECV, &ad);
4276                 if (err)
4277                         return err;
4278         }
4279
4280         return err;
4281 }
4282
4283 static int selinux_socket_getpeersec_stream(struct socket *sock, char __user *optval,
4284                                             int __user *optlen, unsigned len)
4285 {
4286         int err = 0;
4287         char *scontext;
4288         u32 scontext_len;
4289         struct sk_security_struct *sksec = sock->sk->sk_security;
4290         u32 peer_sid = SECSID_NULL;
4291
4292         if (sksec->sclass == SECCLASS_UNIX_STREAM_SOCKET ||
4293             sksec->sclass == SECCLASS_TCP_SOCKET)
4294                 peer_sid = sksec->peer_sid;
4295         if (peer_sid == SECSID_NULL)
4296                 return -ENOPROTOOPT;
4297
4298         err = security_sid_to_context(peer_sid, &scontext, &scontext_len);
4299         if (err)
4300                 return err;
4301
4302         if (scontext_len > len) {
4303                 err = -ERANGE;
4304                 goto out_len;
4305         }
4306
4307         if (copy_to_user(optval, scontext, scontext_len))
4308                 err = -EFAULT;
4309
4310 out_len:
4311         if (put_user(scontext_len, optlen))
4312                 err = -EFAULT;
4313         kfree(scontext);
4314         return err;
4315 }
4316
4317 static int selinux_socket_getpeersec_dgram(struct socket *sock, struct sk_buff *skb, u32 *secid)
4318 {
4319         u32 peer_secid = SECSID_NULL;
4320         u16 family;
4321
4322         if (skb && skb->protocol == htons(ETH_P_IP))
4323                 family = PF_INET;
4324         else if (skb && skb->protocol == htons(ETH_P_IPV6))
4325                 family = PF_INET6;
4326         else if (sock)
4327                 family = sock->sk->sk_family;
4328         else
4329                 goto out;
4330
4331         if (sock && family == PF_UNIX)
4332                 selinux_inode_getsecid(SOCK_INODE(sock), &peer_secid);
4333         else if (skb)
4334                 selinux_skb_peerlbl_sid(skb, family, &peer_secid);
4335
4336 out:
4337         *secid = peer_secid;
4338         if (peer_secid == SECSID_NULL)
4339                 return -EINVAL;
4340         return 0;
4341 }
4342
4343 static int selinux_sk_alloc_security(struct sock *sk, int family, gfp_t priority)
4344 {
4345         struct sk_security_struct *sksec;
4346
4347         sksec = kzalloc(sizeof(*sksec), priority);
4348         if (!sksec)
4349                 return -ENOMEM;
4350
4351         sksec->peer_sid = SECINITSID_UNLABELED;
4352         sksec->sid = SECINITSID_UNLABELED;
4353         selinux_netlbl_sk_security_reset(sksec);
4354         sk->sk_security = sksec;
4355
4356         return 0;
4357 }
4358
4359 static void selinux_sk_free_security(struct sock *sk)
4360 {
4361         struct sk_security_struct *sksec = sk->sk_security;
4362
4363         sk->sk_security = NULL;
4364         selinux_netlbl_sk_security_free(sksec);
4365         kfree(sksec);
4366 }
4367
4368 static void selinux_sk_clone_security(const struct sock *sk, struct sock *newsk)
4369 {
4370         struct sk_security_struct *sksec = sk->sk_security;
4371         struct sk_security_struct *newsksec = newsk->sk_security;
4372
4373         newsksec->sid = sksec->sid;
4374         newsksec->peer_sid = sksec->peer_sid;
4375         newsksec->sclass = sksec->sclass;
4376
4377         selinux_netlbl_sk_security_reset(newsksec);
4378 }
4379
4380 static void selinux_sk_getsecid(struct sock *sk, u32 *secid)
4381 {
4382         if (!sk)
4383                 *secid = SECINITSID_ANY_SOCKET;
4384         else {
4385                 struct sk_security_struct *sksec = sk->sk_security;
4386
4387                 *secid = sksec->sid;
4388         }
4389 }
4390
4391 static void selinux_sock_graft(struct sock *sk, struct socket *parent)
4392 {
4393         struct inode_security_struct *isec = SOCK_INODE(parent)->i_security;
4394         struct sk_security_struct *sksec = sk->sk_security;
4395
4396         if (sk->sk_family == PF_INET || sk->sk_family == PF_INET6 ||
4397             sk->sk_family == PF_UNIX)
4398                 isec->sid = sksec->sid;
4399         sksec->sclass = isec->sclass;
4400 }
4401
4402 static int selinux_inet_conn_request(struct sock *sk, struct sk_buff *skb,
4403                                      struct request_sock *req)
4404 {
4405         struct sk_security_struct *sksec = sk->sk_security;
4406         int err;
4407         u16 family = sk->sk_family;
4408         u32 newsid;
4409         u32 peersid;
4410
4411         /* handle mapped IPv4 packets arriving via IPv6 sockets */
4412         if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
4413                 family = PF_INET;
4414
4415         err = selinux_skb_peerlbl_sid(skb, family, &peersid);
4416         if (err)
4417                 return err;
4418         if (peersid == SECSID_NULL) {
4419                 req->secid = sksec->sid;
4420                 req->peer_secid = SECSID_NULL;
4421         } else {
4422                 err = security_sid_mls_copy(sksec->sid, peersid, &newsid);
4423                 if (err)
4424                         return err;
4425                 req->secid = newsid;
4426                 req->peer_secid = peersid;
4427         }
4428
4429         return selinux_netlbl_inet_conn_request(req, family);
4430 }
4431
4432 static void selinux_inet_csk_clone(struct sock *newsk,
4433                                    const struct request_sock *req)
4434 {
4435         struct sk_security_struct *newsksec = newsk->sk_security;
4436
4437         newsksec->sid = req->secid;
4438         newsksec->peer_sid = req->peer_secid;
4439         /* NOTE: Ideally, we should also get the isec->sid for the
4440            new socket in sync, but we don't have the isec available yet.
4441            So we will wait until sock_graft to do it, by which
4442            time it will have been created and available. */
4443
4444         /* We don't need to take any sort of lock here as we are the only
4445          * thread with access to newsksec */
4446         selinux_netlbl_inet_csk_clone(newsk, req->rsk_ops->family);
4447 }
4448
4449 static void selinux_inet_conn_established(struct sock *sk, struct sk_buff *skb)
4450 {
4451         u16 family = sk->sk_family;
4452         struct sk_security_struct *sksec = sk->sk_security;
4453
4454         /* handle mapped IPv4 packets arriving via IPv6 sockets */
4455         if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
4456                 family = PF_INET;
4457
4458         selinux_skb_peerlbl_sid(skb, family, &sksec->peer_sid);
4459 }
4460
4461 static void selinux_skb_owned_by(struct sk_buff *skb, struct sock *sk)
4462 {
4463         skb_set_owner_w(skb, sk);
4464 }
4465
4466 static int selinux_secmark_relabel_packet(u32 sid)
4467 {
4468         const struct task_security_struct *__tsec;
4469         u32 tsid;
4470
4471         __tsec = current_security();
4472         tsid = __tsec->sid;
4473
4474         return avc_has_perm(tsid, sid, SECCLASS_PACKET, PACKET__RELABELTO, NULL);
4475 }
4476
4477 static void selinux_secmark_refcount_inc(void)
4478 {
4479         atomic_inc(&selinux_secmark_refcount);
4480 }
4481
4482 static void selinux_secmark_refcount_dec(void)
4483 {
4484         atomic_dec(&selinux_secmark_refcount);
4485 }
4486
4487 static void selinux_req_classify_flow(const struct request_sock *req,
4488                                       struct flowi *fl)
4489 {
4490         fl->flowi_secid = req->secid;
4491 }
4492
4493 static int selinux_tun_dev_alloc_security(void **security)
4494 {
4495         struct tun_security_struct *tunsec;
4496
4497         tunsec = kzalloc(sizeof(*tunsec), GFP_KERNEL);
4498         if (!tunsec)
4499                 return -ENOMEM;
4500         tunsec->sid = current_sid();
4501
4502         *security = tunsec;
4503         return 0;
4504 }
4505
4506 static void selinux_tun_dev_free_security(void *security)
4507 {
4508         kfree(security);
4509 }
4510
4511 static int selinux_tun_dev_create(void)
4512 {
4513         u32 sid = current_sid();
4514
4515         /* we aren't taking into account the "sockcreate" SID since the socket
4516          * that is being created here is not a socket in the traditional sense,
4517          * instead it is a private sock, accessible only to the kernel, and
4518          * representing a wide range of network traffic spanning multiple
4519          * connections unlike traditional sockets - check the TUN driver to
4520          * get a better understanding of why this socket is special */
4521
4522         return avc_has_perm(sid, sid, SECCLASS_TUN_SOCKET, TUN_SOCKET__CREATE,
4523                             NULL);
4524 }
4525
4526 static int selinux_tun_dev_attach_queue(void *security)
4527 {
4528         struct tun_security_struct *tunsec = security;
4529
4530         return avc_has_perm(current_sid(), tunsec->sid, SECCLASS_TUN_SOCKET,
4531                             TUN_SOCKET__ATTACH_QUEUE, NULL);
4532 }
4533
4534 static int selinux_tun_dev_attach(struct sock *sk, void *security)
4535 {
4536         struct tun_security_struct *tunsec = security;
4537         struct sk_security_struct *sksec = sk->sk_security;
4538
4539         /* we don't currently perform any NetLabel based labeling here and it
4540          * isn't clear that we would want to do so anyway; while we could apply
4541          * labeling without the support of the TUN user the resulting labeled
4542          * traffic from the other end of the connection would almost certainly
4543          * cause confusion to the TUN user that had no idea network labeling
4544          * protocols were being used */
4545
4546         sksec->sid = tunsec->sid;
4547         sksec->sclass = SECCLASS_TUN_SOCKET;
4548
4549         return 0;
4550 }
4551
4552 static int selinux_tun_dev_open(void *security)
4553 {
4554         struct tun_security_struct *tunsec = security;
4555         u32 sid = current_sid();
4556         int err;
4557
4558         err = avc_has_perm(sid, tunsec->sid, SECCLASS_TUN_SOCKET,
4559                            TUN_SOCKET__RELABELFROM, NULL);
4560         if (err)
4561                 return err;
4562         err = avc_has_perm(sid, sid, SECCLASS_TUN_SOCKET,
4563                            TUN_SOCKET__RELABELTO, NULL);
4564         if (err)
4565                 return err;
4566         tunsec->sid = sid;
4567
4568         return 0;
4569 }
4570
4571 static int selinux_nlmsg_perm(struct sock *sk, struct sk_buff *skb)
4572 {
4573         int err = 0;
4574         u32 perm;
4575         struct nlmsghdr *nlh;
4576         struct sk_security_struct *sksec = sk->sk_security;
4577
4578         if (skb->len < NLMSG_HDRLEN) {
4579                 err = -EINVAL;
4580                 goto out;
4581         }
4582         nlh = nlmsg_hdr(skb);
4583
4584         err = selinux_nlmsg_lookup(sksec->sclass, nlh->nlmsg_type, &perm);
4585         if (err) {
4586                 if (err == -EINVAL) {
4587                         audit_log(current->audit_context, GFP_KERNEL, AUDIT_SELINUX_ERR,
4588                                   "SELinux:  unrecognized netlink message"
4589                                   " type=%hu for sclass=%hu\n",
4590                                   nlh->nlmsg_type, sksec->sclass);
4591                         if (!selinux_enforcing || security_get_allow_unknown())
4592                                 err = 0;
4593                 }
4594
4595                 /* Ignore */
4596                 if (err == -ENOENT)
4597                         err = 0;
4598                 goto out;
4599         }
4600
4601         err = sock_has_perm(current, sk, perm);
4602 out:
4603         return err;
4604 }
4605
4606 #ifdef CONFIG_NETFILTER
4607
4608 static unsigned int selinux_ip_forward(struct sk_buff *skb, int ifindex,
4609                                        u16 family)
4610 {
4611         int err;
4612         char *addrp;
4613         u32 peer_sid;
4614         struct common_audit_data ad;
4615         struct lsm_network_audit net = {0,};
4616         u8 secmark_active;
4617         u8 netlbl_active;
4618         u8 peerlbl_active;
4619
4620         if (!selinux_policycap_netpeer)
4621                 return NF_ACCEPT;
4622
4623         secmark_active = selinux_secmark_enabled();
4624         netlbl_active = netlbl_enabled();
4625         peerlbl_active = netlbl_active || selinux_xfrm_enabled();
4626         if (!secmark_active && !peerlbl_active)
4627                 return NF_ACCEPT;
4628
4629         if (selinux_skb_peerlbl_sid(skb, family, &peer_sid) != 0)
4630                 return NF_DROP;
4631
4632         ad.type = LSM_AUDIT_DATA_NET;
4633         ad.u.net = &net;
4634         ad.u.net->netif = ifindex;
4635         ad.u.net->family = family;
4636         if (selinux_parse_skb(skb, &ad, &addrp, 1, NULL) != 0)
4637                 return NF_DROP;
4638
4639         if (peerlbl_active) {
4640                 err = selinux_inet_sys_rcv_skb(ifindex, addrp, family,
4641                                                peer_sid, &ad);
4642                 if (err) {
4643                         selinux_netlbl_err(skb, err, 1);
4644                         return NF_DROP;
4645                 }
4646         }
4647
4648         if (secmark_active)
4649                 if (avc_has_perm(peer_sid, skb->secmark,
4650                                  SECCLASS_PACKET, PACKET__FORWARD_IN, &ad))
4651                         return NF_DROP;
4652
4653         if (netlbl_active)
4654                 /* we do this in the FORWARD path and not the POST_ROUTING
4655                  * path because we want to make sure we apply the necessary
4656                  * labeling before IPsec is applied so we can leverage AH
4657                  * protection */
4658                 if (selinux_netlbl_skbuff_setsid(skb, family, peer_sid) != 0)
4659                         return NF_DROP;
4660
4661         return NF_ACCEPT;
4662 }
4663
4664 static unsigned int selinux_ipv4_forward(unsigned int hooknum,
4665                                          struct sk_buff *skb,
4666                                          const struct net_device *in,
4667                                          const struct net_device *out,
4668                                          int (*okfn)(struct sk_buff *))
4669 {
4670         return selinux_ip_forward(skb, in->ifindex, PF_INET);
4671 }
4672
4673 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
4674 static unsigned int selinux_ipv6_forward(unsigned int hooknum,
4675                                          struct sk_buff *skb,
4676                                          const struct net_device *in,
4677                                          const struct net_device *out,
4678                                          int (*okfn)(struct sk_buff *))
4679 {
4680         return selinux_ip_forward(skb, in->ifindex, PF_INET6);
4681 }
4682 #endif  /* IPV6 */
4683
4684 static unsigned int selinux_ip_output(struct sk_buff *skb,
4685                                       u16 family)
4686 {
4687         u32 sid;
4688
4689         if (!netlbl_enabled())
4690                 return NF_ACCEPT;
4691
4692         /* we do this in the LOCAL_OUT path and not the POST_ROUTING path
4693          * because we want to make sure we apply the necessary labeling
4694          * before IPsec is applied so we can leverage AH protection */
4695         if (skb->sk) {
4696                 struct sk_security_struct *sksec = skb->sk->sk_security;
4697                 sid = sksec->sid;
4698         } else
4699                 sid = SECINITSID_KERNEL;
4700         if (selinux_netlbl_skbuff_setsid(skb, family, sid) != 0)
4701                 return NF_DROP;
4702
4703         return NF_ACCEPT;
4704 }
4705
4706 static unsigned int selinux_ipv4_output(unsigned int hooknum,
4707                                         struct sk_buff *skb,
4708                                         const struct net_device *in,
4709                                         const struct net_device *out,
4710                                         int (*okfn)(struct sk_buff *))
4711 {
4712         return selinux_ip_output(skb, PF_INET);
4713 }
4714
4715 static unsigned int selinux_ip_postroute_compat(struct sk_buff *skb,
4716                                                 int ifindex,
4717                                                 u16 family)
4718 {
4719         struct sock *sk = skb->sk;
4720         struct sk_security_struct *sksec;
4721         struct common_audit_data ad;
4722         struct lsm_network_audit net = {0,};
4723         char *addrp;
4724         u8 proto;
4725
4726         if (sk == NULL)
4727                 return NF_ACCEPT;
4728         sksec = sk->sk_security;
4729
4730         ad.type = LSM_AUDIT_DATA_NET;
4731         ad.u.net = &net;
4732         ad.u.net->netif = ifindex;
4733         ad.u.net->family = family;
4734         if (selinux_parse_skb(skb, &ad, &addrp, 0, &proto))
4735                 return NF_DROP;
4736
4737         if (selinux_secmark_enabled())
4738                 if (avc_has_perm(sksec->sid, skb->secmark,
4739                                  SECCLASS_PACKET, PACKET__SEND, &ad))
4740                         return NF_DROP_ERR(-ECONNREFUSED);
4741
4742         if (selinux_xfrm_postroute_last(sksec->sid, skb, &ad, proto))
4743                 return NF_DROP_ERR(-ECONNREFUSED);
4744
4745         return NF_ACCEPT;
4746 }
4747
4748 static unsigned int selinux_ip_postroute(struct sk_buff *skb, int ifindex,
4749                                          u16 family)
4750 {
4751         u32 secmark_perm;
4752         u32 peer_sid;
4753         struct sock *sk;
4754         struct common_audit_data ad;
4755         struct lsm_network_audit net = {0,};
4756         char *addrp;
4757         u8 secmark_active;
4758         u8 peerlbl_active;
4759
4760         /* If any sort of compatibility mode is enabled then handoff processing
4761          * to the selinux_ip_postroute_compat() function to deal with the
4762          * special handling.  We do this in an attempt to keep this function
4763          * as fast and as clean as possible. */
4764         if (!selinux_policycap_netpeer)
4765                 return selinux_ip_postroute_compat(skb, ifindex, family);
4766 #ifdef CONFIG_XFRM
4767         /* If skb->dst->xfrm is non-NULL then the packet is undergoing an IPsec
4768          * packet transformation so allow the packet to pass without any checks
4769          * since we'll have another chance to perform access control checks
4770          * when the packet is on it's final way out.
4771          * NOTE: there appear to be some IPv6 multicast cases where skb->dst
4772          *       is NULL, in this case go ahead and apply access control. */
4773         if (skb_dst(skb) != NULL && skb_dst(skb)->xfrm != NULL)
4774                 return NF_ACCEPT;
4775 #endif
4776         secmark_active = selinux_secmark_enabled();
4777         peerlbl_active = netlbl_enabled() || selinux_xfrm_enabled();
4778         if (!secmark_active && !peerlbl_active)
4779                 return NF_ACCEPT;
4780
4781         /* if the packet is being forwarded then get the peer label from the
4782          * packet itself; otherwise check to see if it is from a local
4783          * application or the kernel, if from an application get the peer label
4784          * from the sending socket, otherwise use the kernel's sid */
4785         sk = skb->sk;
4786         if (sk == NULL) {
4787                 if (skb->skb_iif) {
4788                         secmark_perm = PACKET__FORWARD_OUT;
4789                         if (selinux_skb_peerlbl_sid(skb, family, &peer_sid))
4790                                 return NF_DROP;
4791                 } else {
4792                         secmark_perm = PACKET__SEND;
4793                         peer_sid = SECINITSID_KERNEL;
4794                 }
4795         } else {
4796                 struct sk_security_struct *sksec = sk->sk_security;
4797                 peer_sid = sksec->sid;
4798                 secmark_perm = PACKET__SEND;
4799         }
4800
4801         ad.type = LSM_AUDIT_DATA_NET;
4802         ad.u.net = &net;
4803         ad.u.net->netif = ifindex;
4804         ad.u.net->family = family;
4805         if (selinux_parse_skb(skb, &ad, &addrp, 0, NULL))
4806                 return NF_DROP;
4807
4808         if (secmark_active)
4809                 if (avc_has_perm(peer_sid, skb->secmark,
4810                                  SECCLASS_PACKET, secmark_perm, &ad))
4811                         return NF_DROP_ERR(-ECONNREFUSED);
4812
4813         if (peerlbl_active) {
4814                 u32 if_sid;
4815                 u32 node_sid;
4816
4817                 if (sel_netif_sid(ifindex, &if_sid))
4818                         return NF_DROP;
4819                 if (avc_has_perm(peer_sid, if_sid,
4820                                  SECCLASS_NETIF, NETIF__EGRESS, &ad))
4821                         return NF_DROP_ERR(-ECONNREFUSED);
4822
4823                 if (sel_netnode_sid(addrp, family, &node_sid))
4824                         return NF_DROP;
4825                 if (avc_has_perm(peer_sid, node_sid,
4826                                  SECCLASS_NODE, NODE__SENDTO, &ad))
4827                         return NF_DROP_ERR(-ECONNREFUSED);
4828         }
4829
4830         return NF_ACCEPT;
4831 }
4832
4833 static unsigned int selinux_ipv4_postroute(unsigned int hooknum,
4834                                            struct sk_buff *skb,
4835                                            const struct net_device *in,
4836                                            const struct net_device *out,
4837                                            int (*okfn)(struct sk_buff *))
4838 {
4839         return selinux_ip_postroute(skb, out->ifindex, PF_INET);
4840 }
4841
4842 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
4843 static unsigned int selinux_ipv6_postroute(unsigned int hooknum,
4844                                            struct sk_buff *skb,
4845                                            const struct net_device *in,
4846                                            const struct net_device *out,
4847                                            int (*okfn)(struct sk_buff *))
4848 {
4849         return selinux_ip_postroute(skb, out->ifindex, PF_INET6);
4850 }
4851 #endif  /* IPV6 */
4852
4853 #endif  /* CONFIG_NETFILTER */
4854
4855 static int selinux_netlink_send(struct sock *sk, struct sk_buff *skb)
4856 {
4857         int err;
4858
4859         err = cap_netlink_send(sk, skb);
4860         if (err)
4861                 return err;
4862
4863         return selinux_nlmsg_perm(sk, skb);
4864 }
4865
4866 static int ipc_alloc_security(struct task_struct *task,
4867                               struct kern_ipc_perm *perm,
4868                               u16 sclass)
4869 {
4870         struct ipc_security_struct *isec;
4871         u32 sid;
4872
4873         isec = kzalloc(sizeof(struct ipc_security_struct), GFP_KERNEL);
4874         if (!isec)
4875                 return -ENOMEM;
4876
4877         sid = task_sid(task);
4878         isec->sclass = sclass;
4879         isec->sid = sid;
4880         perm->security = isec;
4881
4882         return 0;
4883 }
4884
4885 static void ipc_free_security(struct kern_ipc_perm *perm)
4886 {
4887         struct ipc_security_struct *isec = perm->security;
4888         perm->security = NULL;
4889         kfree(isec);
4890 }
4891
4892 static int msg_msg_alloc_security(struct msg_msg *msg)
4893 {
4894         struct msg_security_struct *msec;
4895
4896         msec = kzalloc(sizeof(struct msg_security_struct), GFP_KERNEL);
4897         if (!msec)
4898                 return -ENOMEM;
4899
4900         msec->sid = SECINITSID_UNLABELED;
4901         msg->security = msec;
4902
4903         return 0;
4904 }
4905
4906 static void msg_msg_free_security(struct msg_msg *msg)
4907 {
4908         struct msg_security_struct *msec = msg->security;
4909
4910         msg->security = NULL;
4911         kfree(msec);
4912 }
4913
4914 static int ipc_has_perm(struct kern_ipc_perm *ipc_perms,
4915                         u32 perms)
4916 {
4917         struct ipc_security_struct *isec;
4918         struct common_audit_data ad;
4919         u32 sid = current_sid();
4920
4921         isec = ipc_perms->security;
4922
4923         ad.type = LSM_AUDIT_DATA_IPC;
4924         ad.u.ipc_id = ipc_perms->key;
4925
4926         return avc_has_perm(sid, isec->sid, isec->sclass, perms, &ad);
4927 }
4928
4929 static int selinux_msg_msg_alloc_security(struct msg_msg *msg)
4930 {
4931         return msg_msg_alloc_security(msg);
4932 }
4933
4934 static void selinux_msg_msg_free_security(struct msg_msg *msg)
4935 {
4936         msg_msg_free_security(msg);
4937 }
4938
4939 /* message queue security operations */
4940 static int selinux_msg_queue_alloc_security(struct msg_queue *msq)
4941 {
4942         struct ipc_security_struct *isec;
4943         struct common_audit_data ad;
4944         u32 sid = current_sid();
4945         int rc;
4946
4947         rc = ipc_alloc_security(current, &msq->q_perm, SECCLASS_MSGQ);
4948         if (rc)
4949                 return rc;
4950
4951         isec = msq->q_perm.security;
4952
4953         ad.type = LSM_AUDIT_DATA_IPC;
4954         ad.u.ipc_id = msq->q_perm.key;
4955
4956         rc = avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
4957                           MSGQ__CREATE, &ad);
4958         if (rc) {
4959                 ipc_free_security(&msq->q_perm);
4960                 return rc;
4961         }
4962         return 0;
4963 }
4964
4965 static void selinux_msg_queue_free_security(struct msg_queue *msq)
4966 {
4967         ipc_free_security(&msq->q_perm);
4968 }
4969
4970 static int selinux_msg_queue_associate(struct msg_queue *msq, int msqflg)
4971 {
4972         struct ipc_security_struct *isec;
4973         struct common_audit_data ad;
4974         u32 sid = current_sid();
4975
4976         isec = msq->q_perm.security;
4977
4978         ad.type = LSM_AUDIT_DATA_IPC;
4979         ad.u.ipc_id = msq->q_perm.key;
4980
4981         return avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
4982                             MSGQ__ASSOCIATE, &ad);
4983 }
4984
4985 static int selinux_msg_queue_msgctl(struct msg_queue *msq, int cmd)
4986 {
4987         int err;
4988         int perms;
4989
4990         switch (cmd) {
4991         case IPC_INFO:
4992         case MSG_INFO:
4993                 /* No specific object, just general system-wide information. */
4994                 return task_has_system(current, SYSTEM__IPC_INFO);
4995         case IPC_STAT:
4996         case MSG_STAT:
4997                 perms = MSGQ__GETATTR | MSGQ__ASSOCIATE;
4998                 break;
4999         case IPC_SET:
5000                 perms = MSGQ__SETATTR;
5001                 break;
5002         case IPC_RMID:
5003                 perms = MSGQ__DESTROY;
5004                 break;
5005         default:
5006                 return 0;
5007         }
5008
5009         err = ipc_has_perm(&msq->q_perm, perms);
5010         return err;
5011 }
5012
5013 static int selinux_msg_queue_msgsnd(struct msg_queue *msq, struct msg_msg *msg, int msqflg)
5014 {
5015         struct ipc_security_struct *isec;
5016         struct msg_security_struct *msec;
5017         struct common_audit_data ad;
5018         u32 sid = current_sid();
5019         int rc;
5020
5021         isec = msq->q_perm.security;
5022         msec = msg->security;
5023
5024         /*
5025          * First time through, need to assign label to the message
5026          */
5027         if (msec->sid == SECINITSID_UNLABELED) {
5028                 /*
5029                  * Compute new sid based on current process and
5030                  * message queue this message will be stored in
5031                  */
5032                 rc = security_transition_sid(sid, isec->sid, SECCLASS_MSG,
5033                                              NULL, &msec->sid);
5034                 if (rc)
5035                         return rc;
5036         }
5037
5038         ad.type = LSM_AUDIT_DATA_IPC;
5039         ad.u.ipc_id = msq->q_perm.key;
5040
5041         /* Can this process write to the queue? */
5042         rc = avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
5043                           MSGQ__WRITE, &ad);
5044         if (!rc)
5045                 /* Can this process send the message */
5046                 rc = avc_has_perm(sid, msec->sid, SECCLASS_MSG,
5047                                   MSG__SEND, &ad);
5048         if (!rc)
5049                 /* Can the message be put in the queue? */
5050                 rc = avc_has_perm(msec->sid, isec->sid, SECCLASS_MSGQ,
5051                                   MSGQ__ENQUEUE, &ad);
5052
5053         return rc;
5054 }
5055
5056 static int selinux_msg_queue_msgrcv(struct msg_queue *msq, struct msg_msg *msg,
5057                                     struct task_struct *target,
5058                                     long type, int mode)
5059 {
5060         struct ipc_security_struct *isec;
5061         struct msg_security_struct *msec;
5062         struct common_audit_data ad;
5063         u32 sid = task_sid(target);
5064         int rc;
5065
5066         isec = msq->q_perm.security;
5067         msec = msg->security;
5068
5069         ad.type = LSM_AUDIT_DATA_IPC;
5070         ad.u.ipc_id = msq->q_perm.key;
5071
5072         rc = avc_has_perm(sid, isec->sid,
5073                           SECCLASS_MSGQ, MSGQ__READ, &ad);
5074         if (!rc)
5075                 rc = avc_has_perm(sid, msec->sid,
5076                                   SECCLASS_MSG, MSG__RECEIVE, &ad);
5077         return rc;
5078 }
5079
5080 /* Shared Memory security operations */
5081 static int selinux_shm_alloc_security(struct shmid_kernel *shp)
5082 {
5083         struct ipc_security_struct *isec;
5084         struct common_audit_data ad;
5085         u32 sid = current_sid();
5086         int rc;
5087
5088         rc = ipc_alloc_security(current, &shp->shm_perm, SECCLASS_SHM);
5089         if (rc)
5090                 return rc;
5091
5092         isec = shp->shm_perm.security;
5093
5094         ad.type = LSM_AUDIT_DATA_IPC;
5095         ad.u.ipc_id = shp->shm_perm.key;
5096
5097         rc = avc_has_perm(sid, isec->sid, SECCLASS_SHM,
5098                           SHM__CREATE, &ad);
5099         if (rc) {
5100                 ipc_free_security(&shp->shm_perm);
5101                 return rc;
5102         }
5103         return 0;
5104 }
5105
5106 static void selinux_shm_free_security(struct shmid_kernel *shp)
5107 {
5108         ipc_free_security(&shp->shm_perm);
5109 }
5110
5111 static int selinux_shm_associate(struct shmid_kernel *shp, int shmflg)
5112 {
5113         struct ipc_security_struct *isec;
5114         struct common_audit_data ad;
5115         u32 sid = current_sid();
5116
5117         isec = shp->shm_perm.security;
5118
5119         ad.type = LSM_AUDIT_DATA_IPC;
5120         ad.u.ipc_id = shp->shm_perm.key;
5121
5122         return avc_has_perm(sid, isec->sid, SECCLASS_SHM,
5123                             SHM__ASSOCIATE, &ad);
5124 }
5125
5126 /* Note, at this point, shp is locked down */
5127 static int selinux_shm_shmctl(struct shmid_kernel *shp, int cmd)
5128 {
5129         int perms;
5130         int err;
5131
5132         switch (cmd) {
5133         case IPC_INFO:
5134         case SHM_INFO:
5135                 /* No specific object, just general system-wide information. */
5136                 return task_has_system(current, SYSTEM__IPC_INFO);
5137         case IPC_STAT:
5138         case SHM_STAT:
5139                 perms = SHM__GETATTR | SHM__ASSOCIATE;
5140                 break;
5141         case IPC_SET:
5142                 perms = SHM__SETATTR;
5143                 break;
5144         case SHM_LOCK:
5145         case SHM_UNLOCK:
5146                 perms = SHM__LOCK;
5147                 break;
5148         case IPC_RMID:
5149                 perms = SHM__DESTROY;
5150                 break;
5151         default:
5152                 return 0;
5153         }
5154
5155         err = ipc_has_perm(&shp->shm_perm, perms);
5156         return err;
5157 }
5158
5159 static int selinux_shm_shmat(struct shmid_kernel *shp,
5160                              char __user *shmaddr, int shmflg)
5161 {
5162         u32 perms;
5163
5164         if (shmflg & SHM_RDONLY)
5165                 perms = SHM__READ;
5166         else
5167                 perms = SHM__READ | SHM__WRITE;
5168
5169         return ipc_has_perm(&shp->shm_perm, perms);
5170 }
5171
5172 /* Semaphore security operations */
5173 static int selinux_sem_alloc_security(struct sem_array *sma)
5174 {
5175         struct ipc_security_struct *isec;
5176         struct common_audit_data ad;
5177         u32 sid = current_sid();
5178         int rc;
5179
5180         rc = ipc_alloc_security(current, &sma->sem_perm, SECCLASS_SEM);
5181         if (rc)
5182                 return rc;
5183
5184         isec = sma->sem_perm.security;
5185
5186         ad.type = LSM_AUDIT_DATA_IPC;
5187         ad.u.ipc_id = sma->sem_perm.key;
5188
5189         rc = avc_has_perm(sid, isec->sid, SECCLASS_SEM,
5190                           SEM__CREATE, &ad);
5191         if (rc) {
5192                 ipc_free_security(&sma->sem_perm);
5193                 return rc;
5194         }
5195         return 0;
5196 }
5197
5198 static void selinux_sem_free_security(struct sem_array *sma)
5199 {
5200         ipc_free_security(&sma->sem_perm);
5201 }
5202
5203 static int selinux_sem_associate(struct sem_array *sma, int semflg)
5204 {
5205         struct ipc_security_struct *isec;
5206         struct common_audit_data ad;
5207         u32 sid = current_sid();
5208
5209         isec = sma->sem_perm.security;
5210
5211         ad.type = LSM_AUDIT_DATA_IPC;
5212         ad.u.ipc_id = sma->sem_perm.key;
5213
5214         return avc_has_perm(sid, isec->sid, SECCLASS_SEM,
5215                             SEM__ASSOCIATE, &ad);
5216 }
5217
5218 /* Note, at this point, sma is locked down */
5219 static int selinux_sem_semctl(struct sem_array *sma, int cmd)
5220 {
5221         int err;
5222         u32 perms;
5223
5224         switch (cmd) {
5225         case IPC_INFO:
5226         case SEM_INFO:
5227                 /* No specific object, just general system-wide information. */
5228                 return task_has_system(current, SYSTEM__IPC_INFO);
5229         case GETPID:
5230         case GETNCNT:
5231         case GETZCNT:
5232                 perms = SEM__GETATTR;
5233                 break;
5234         case GETVAL:
5235         case GETALL:
5236                 perms = SEM__READ;
5237                 break;
5238         case SETVAL:
5239         case SETALL:
5240                 perms = SEM__WRITE;
5241                 break;
5242         case IPC_RMID:
5243                 perms = SEM__DESTROY;
5244                 break;
5245         case IPC_SET:
5246                 perms = SEM__SETATTR;
5247                 break;
5248         case IPC_STAT:
5249         case SEM_STAT:
5250                 perms = SEM__GETATTR | SEM__ASSOCIATE;
5251                 break;
5252         default:
5253                 return 0;
5254         }
5255
5256         err = ipc_has_perm(&sma->sem_perm, perms);
5257         return err;
5258 }
5259
5260 static int selinux_sem_semop(struct sem_array *sma,
5261                              struct sembuf *sops, unsigned nsops, int alter)
5262 {
5263         u32 perms;
5264
5265         if (alter)
5266                 perms = SEM__READ | SEM__WRITE;
5267         else
5268                 perms = SEM__READ;
5269
5270         return ipc_has_perm(&sma->sem_perm, perms);
5271 }
5272
5273 static int selinux_ipc_permission(struct kern_ipc_perm *ipcp, short flag)
5274 {
5275         u32 av = 0;
5276
5277         av = 0;
5278         if (flag & S_IRUGO)
5279                 av |= IPC__UNIX_READ;
5280         if (flag & S_IWUGO)
5281                 av |= IPC__UNIX_WRITE;
5282
5283         if (av == 0)
5284                 return 0;
5285
5286         return ipc_has_perm(ipcp, av);
5287 }
5288
5289 static void selinux_ipc_getsecid(struct kern_ipc_perm *ipcp, u32 *secid)
5290 {
5291         struct ipc_security_struct *isec = ipcp->security;
5292         *secid = isec->sid;
5293 }
5294
5295 static void selinux_d_instantiate(struct dentry *dentry, struct inode *inode)
5296 {
5297         if (inode)
5298                 inode_doinit_with_dentry(inode, dentry);
5299 }
5300
5301 static int selinux_getprocattr(struct task_struct *p,
5302                                char *name, char **value)
5303 {
5304         const struct task_security_struct *__tsec;
5305         u32 sid;
5306         int error;
5307         unsigned len;
5308
5309         if (current != p) {
5310                 error = current_has_perm(p, PROCESS__GETATTR);
5311                 if (error)
5312                         return error;
5313         }
5314
5315         rcu_read_lock();
5316         __tsec = __task_cred(p)->security;
5317
5318         if (!strcmp(name, "current"))
5319                 sid = __tsec->sid;
5320         else if (!strcmp(name, "prev"))
5321                 sid = __tsec->osid;
5322         else if (!strcmp(name, "exec"))
5323                 sid = __tsec->exec_sid;
5324         else if (!strcmp(name, "fscreate"))
5325                 sid = __tsec->create_sid;
5326         else if (!strcmp(name, "keycreate"))
5327                 sid = __tsec->keycreate_sid;
5328         else if (!strcmp(name, "sockcreate"))
5329                 sid = __tsec->sockcreate_sid;
5330         else
5331                 goto invalid;
5332         rcu_read_unlock();
5333
5334         if (!sid)
5335                 return 0;
5336
5337         error = security_sid_to_context(sid, value, &len);
5338         if (error)
5339                 return error;
5340         return len;
5341
5342 invalid:
5343         rcu_read_unlock();
5344         return -EINVAL;
5345 }
5346
5347 static int selinux_setprocattr(struct task_struct *p,
5348                                char *name, void *value, size_t size)
5349 {
5350         struct task_security_struct *tsec;
5351         struct task_struct *tracer;
5352         struct cred *new;
5353         u32 sid = 0, ptsid;
5354         int error;
5355         char *str = value;
5356
5357         if (current != p) {
5358                 /* SELinux only allows a process to change its own
5359                    security attributes. */
5360                 return -EACCES;
5361         }
5362
5363         /*
5364          * Basic control over ability to set these attributes at all.
5365          * current == p, but we'll pass them separately in case the
5366          * above restriction is ever removed.
5367          */
5368         if (!strcmp(name, "exec"))
5369                 error = current_has_perm(p, PROCESS__SETEXEC);
5370         else if (!strcmp(name, "fscreate"))
5371                 error = current_has_perm(p, PROCESS__SETFSCREATE);
5372         else if (!strcmp(name, "keycreate"))
5373                 error = current_has_perm(p, PROCESS__SETKEYCREATE);
5374         else if (!strcmp(name, "sockcreate"))
5375                 error = current_has_perm(p, PROCESS__SETSOCKCREATE);
5376         else if (!strcmp(name, "current"))
5377                 error = current_has_perm(p, PROCESS__SETCURRENT);
5378         else
5379                 error = -EINVAL;
5380         if (error)
5381                 return error;
5382
5383         /* Obtain a SID for the context, if one was specified. */
5384         if (size && str[1] && str[1] != '\n') {
5385                 if (str[size-1] == '\n') {
5386                         str[size-1] = 0;
5387                         size--;
5388                 }
5389                 error = security_context_to_sid(value, size, &sid);
5390                 if (error == -EINVAL && !strcmp(name, "fscreate")) {
5391                         if (!capable(CAP_MAC_ADMIN)) {
5392                                 struct audit_buffer *ab;
5393                                 size_t audit_size;
5394
5395                                 /* We strip a nul only if it is at the end, otherwise the
5396                                  * context contains a nul and we should audit that */
5397                                 if (str[size - 1] == '\0')
5398                                         audit_size = size - 1;
5399                                 else
5400                                         audit_size = size;
5401                                 ab = audit_log_start(current->audit_context, GFP_ATOMIC, AUDIT_SELINUX_ERR);
5402                                 audit_log_format(ab, "op=fscreate invalid_context=");
5403                                 audit_log_n_untrustedstring(ab, value, audit_size);
5404                                 audit_log_end(ab);
5405
5406                                 return error;
5407                         }
5408                         error = security_context_to_sid_force(value, size,
5409                                                               &sid);
5410                 }
5411                 if (error)
5412                         return error;
5413         }
5414
5415         new = prepare_creds();
5416         if (!new)
5417                 return -ENOMEM;
5418
5419         /* Permission checking based on the specified context is
5420            performed during the actual operation (execve,
5421            open/mkdir/...), when we know the full context of the
5422            operation.  See selinux_bprm_set_creds for the execve
5423            checks and may_create for the file creation checks. The
5424            operation will then fail if the context is not permitted. */
5425         tsec = new->security;
5426         if (!strcmp(name, "exec")) {
5427                 tsec->exec_sid = sid;
5428         } else if (!strcmp(name, "fscreate")) {
5429                 tsec->create_sid = sid;
5430         } else if (!strcmp(name, "keycreate")) {
5431                 error = may_create_key(sid, p);
5432                 if (error)
5433                         goto abort_change;
5434                 tsec->keycreate_sid = sid;
5435         } else if (!strcmp(name, "sockcreate")) {
5436                 tsec->sockcreate_sid = sid;
5437         } else if (!strcmp(name, "current")) {
5438                 error = -EINVAL;
5439                 if (sid == 0)
5440                         goto abort_change;
5441
5442                 /* Only allow single threaded processes to change context */
5443                 error = -EPERM;
5444                 if (!current_is_single_threaded()) {
5445                         error = security_bounded_transition(tsec->sid, sid);
5446                         if (error)
5447                                 goto abort_change;
5448                 }
5449
5450                 /* Check permissions for the transition. */
5451                 error = avc_has_perm(tsec->sid, sid, SECCLASS_PROCESS,
5452                                      PROCESS__DYNTRANSITION, NULL);
5453                 if (error)
5454                         goto abort_change;
5455
5456                 /* Check for ptracing, and update the task SID if ok.
5457                    Otherwise, leave SID unchanged and fail. */
5458                 ptsid = 0;
5459                 task_lock(p);
5460                 tracer = ptrace_parent(p);
5461                 if (tracer)
5462                         ptsid = task_sid(tracer);
5463                 task_unlock(p);
5464
5465                 if (tracer) {
5466                         error = avc_has_perm(ptsid, sid, SECCLASS_PROCESS,
5467                                              PROCESS__PTRACE, NULL);
5468                         if (error)
5469                                 goto abort_change;
5470                 }
5471
5472                 tsec->sid = sid;
5473         } else {
5474                 error = -EINVAL;
5475                 goto abort_change;
5476         }
5477
5478         commit_creds(new);
5479         return size;
5480
5481 abort_change:
5482         abort_creds(new);
5483         return error;
5484 }
5485
5486 static int selinux_ismaclabel(const char *name)
5487 {
5488         return (strcmp(name, XATTR_SELINUX_SUFFIX) == 0);
5489 }
5490
5491 static int selinux_secid_to_secctx(u32 secid, char **secdata, u32 *seclen)
5492 {
5493         return security_sid_to_context(secid, secdata, seclen);
5494 }
5495
5496 static int selinux_secctx_to_secid(const char *secdata, u32 seclen, u32 *secid)
5497 {
5498         return security_context_to_sid(secdata, seclen, secid);
5499 }
5500
5501 static void selinux_release_secctx(char *secdata, u32 seclen)
5502 {
5503         kfree(secdata);
5504 }
5505
5506 /*
5507  *      called with inode->i_mutex locked
5508  */
5509 static int selinux_inode_notifysecctx(struct inode *inode, void *ctx, u32 ctxlen)
5510 {
5511         return selinux_inode_setsecurity(inode, XATTR_SELINUX_SUFFIX, ctx, ctxlen, 0);
5512 }
5513
5514 /*
5515  *      called with inode->i_mutex locked
5516  */
5517 static int selinux_inode_setsecctx(struct dentry *dentry, void *ctx, u32 ctxlen)
5518 {
5519         return __vfs_setxattr_noperm(dentry, XATTR_NAME_SELINUX, ctx, ctxlen, 0);
5520 }
5521
5522 static int selinux_inode_getsecctx(struct inode *inode, void **ctx, u32 *ctxlen)
5523 {
5524         int len = 0;
5525         len = selinux_inode_getsecurity(inode, XATTR_SELINUX_SUFFIX,
5526                                                 ctx, true);
5527         if (len < 0)
5528                 return len;
5529         *ctxlen = len;
5530         return 0;
5531 }
5532 #ifdef CONFIG_KEYS
5533
5534 static int selinux_key_alloc(struct key *k, const struct cred *cred,
5535                              unsigned long flags)
5536 {
5537         const struct task_security_struct *tsec;
5538         struct key_security_struct *ksec;
5539
5540         ksec = kzalloc(sizeof(struct key_security_struct), GFP_KERNEL);
5541         if (!ksec)
5542                 return -ENOMEM;
5543
5544         tsec = cred->security;
5545         if (tsec->keycreate_sid)
5546                 ksec->sid = tsec->keycreate_sid;
5547         else
5548                 ksec->sid = tsec->sid;
5549
5550         k->security = ksec;
5551         return 0;
5552 }
5553
5554 static void selinux_key_free(struct key *k)
5555 {
5556         struct key_security_struct *ksec = k->security;
5557
5558         k->security = NULL;
5559         kfree(ksec);
5560 }
5561
5562 static int selinux_key_permission(key_ref_t key_ref,
5563                                   const struct cred *cred,
5564                                   key_perm_t perm)
5565 {
5566         struct key *key;
5567         struct key_security_struct *ksec;
5568         u32 sid;
5569
5570         /* if no specific permissions are requested, we skip the
5571            permission check. No serious, additional covert channels
5572            appear to be created. */
5573         if (perm == 0)
5574                 return 0;
5575
5576         sid = cred_sid(cred);
5577
5578         key = key_ref_to_ptr(key_ref);
5579         ksec = key->security;
5580
5581         return avc_has_perm(sid, ksec->sid, SECCLASS_KEY, perm, NULL);
5582 }
5583
5584 static int selinux_key_getsecurity(struct key *key, char **_buffer)
5585 {
5586         struct key_security_struct *ksec = key->security;
5587         char *context = NULL;
5588         unsigned len;
5589         int rc;
5590
5591         rc = security_sid_to_context(ksec->sid, &context, &len);
5592         if (!rc)
5593                 rc = len;
5594         *_buffer = context;
5595         return rc;
5596 }
5597
5598 #endif
5599
5600 static struct security_operations selinux_ops = {
5601         .name =                         "selinux",
5602
5603         .ptrace_access_check =          selinux_ptrace_access_check,
5604         .ptrace_traceme =               selinux_ptrace_traceme,
5605         .capget =                       selinux_capget,
5606         .capset =                       selinux_capset,
5607         .capable =                      selinux_capable,
5608         .quotactl =                     selinux_quotactl,
5609         .quota_on =                     selinux_quota_on,
5610         .syslog =                       selinux_syslog,
5611         .vm_enough_memory =             selinux_vm_enough_memory,
5612
5613         .netlink_send =                 selinux_netlink_send,
5614
5615         .bprm_set_creds =               selinux_bprm_set_creds,
5616         .bprm_committing_creds =        selinux_bprm_committing_creds,
5617         .bprm_committed_creds =         selinux_bprm_committed_creds,
5618         .bprm_secureexec =              selinux_bprm_secureexec,
5619
5620         .sb_alloc_security =            selinux_sb_alloc_security,
5621         .sb_free_security =             selinux_sb_free_security,
5622         .sb_copy_data =                 selinux_sb_copy_data,
5623         .sb_remount =                   selinux_sb_remount,
5624         .sb_kern_mount =                selinux_sb_kern_mount,
5625         .sb_show_options =              selinux_sb_show_options,
5626         .sb_statfs =                    selinux_sb_statfs,
5627         .sb_mount =                     selinux_mount,
5628         .sb_umount =                    selinux_umount,
5629         .sb_set_mnt_opts =              selinux_set_mnt_opts,
5630         .sb_clone_mnt_opts =            selinux_sb_clone_mnt_opts,
5631         .sb_parse_opts_str =            selinux_parse_opts_str,
5632
5633         .dentry_init_security =         selinux_dentry_init_security,
5634
5635         .inode_alloc_security =         selinux_inode_alloc_security,
5636         .inode_free_security =          selinux_inode_free_security,
5637         .inode_init_security =          selinux_inode_init_security,
5638         .inode_create =                 selinux_inode_create,
5639         .inode_link =                   selinux_inode_link,
5640         .inode_unlink =                 selinux_inode_unlink,
5641         .inode_symlink =                selinux_inode_symlink,
5642         .inode_mkdir =                  selinux_inode_mkdir,
5643         .inode_rmdir =                  selinux_inode_rmdir,
5644         .inode_mknod =                  selinux_inode_mknod,
5645         .inode_rename =                 selinux_inode_rename,
5646         .inode_readlink =               selinux_inode_readlink,
5647         .inode_follow_link =            selinux_inode_follow_link,
5648         .inode_permission =             selinux_inode_permission,
5649         .inode_setattr =                selinux_inode_setattr,
5650         .inode_getattr =                selinux_inode_getattr,
5651         .inode_setxattr =               selinux_inode_setxattr,
5652         .inode_post_setxattr =          selinux_inode_post_setxattr,
5653         .inode_getxattr =               selinux_inode_getxattr,
5654         .inode_listxattr =              selinux_inode_listxattr,
5655         .inode_removexattr =            selinux_inode_removexattr,
5656         .inode_getsecurity =            selinux_inode_getsecurity,
5657         .inode_setsecurity =            selinux_inode_setsecurity,
5658         .inode_listsecurity =           selinux_inode_listsecurity,
5659         .inode_getsecid =               selinux_inode_getsecid,
5660
5661         .file_permission =              selinux_file_permission,
5662         .file_alloc_security =          selinux_file_alloc_security,
5663         .file_free_security =           selinux_file_free_security,
5664         .file_ioctl =                   selinux_file_ioctl,
5665         .mmap_file =                    selinux_mmap_file,
5666         .mmap_addr =                    selinux_mmap_addr,
5667         .file_mprotect =                selinux_file_mprotect,
5668         .file_lock =                    selinux_file_lock,
5669         .file_fcntl =                   selinux_file_fcntl,
5670         .file_set_fowner =              selinux_file_set_fowner,
5671         .file_send_sigiotask =          selinux_file_send_sigiotask,
5672         .file_receive =                 selinux_file_receive,
5673
5674         .file_open =                    selinux_file_open,
5675
5676         .task_create =                  selinux_task_create,
5677         .cred_alloc_blank =             selinux_cred_alloc_blank,
5678         .cred_free =                    selinux_cred_free,
5679         .cred_prepare =                 selinux_cred_prepare,
5680         .cred_transfer =                selinux_cred_transfer,
5681         .kernel_act_as =                selinux_kernel_act_as,
5682         .kernel_create_files_as =       selinux_kernel_create_files_as,
5683         .kernel_module_request =        selinux_kernel_module_request,
5684         .task_setpgid =                 selinux_task_setpgid,
5685         .task_getpgid =                 selinux_task_getpgid,
5686         .task_getsid =                  selinux_task_getsid,
5687         .task_getsecid =                selinux_task_getsecid,
5688         .task_setnice =                 selinux_task_setnice,
5689         .task_setioprio =               selinux_task_setioprio,
5690         .task_getioprio =               selinux_task_getioprio,
5691         .task_setrlimit =               selinux_task_setrlimit,
5692         .task_setscheduler =            selinux_task_setscheduler,
5693         .task_getscheduler =            selinux_task_getscheduler,
5694         .task_movememory =              selinux_task_movememory,
5695         .task_kill =                    selinux_task_kill,
5696         .task_wait =                    selinux_task_wait,
5697         .task_to_inode =                selinux_task_to_inode,
5698
5699         .ipc_permission =               selinux_ipc_permission,
5700         .ipc_getsecid =                 selinux_ipc_getsecid,
5701
5702         .msg_msg_alloc_security =       selinux_msg_msg_alloc_security,
5703         .msg_msg_free_security =        selinux_msg_msg_free_security,
5704
5705         .msg_queue_alloc_security =     selinux_msg_queue_alloc_security,
5706         .msg_queue_free_security =      selinux_msg_queue_free_security,
5707         .msg_queue_associate =          selinux_msg_queue_associate,
5708         .msg_queue_msgctl =             selinux_msg_queue_msgctl,
5709         .msg_queue_msgsnd =             selinux_msg_queue_msgsnd,
5710         .msg_queue_msgrcv =             selinux_msg_queue_msgrcv,
5711
5712         .shm_alloc_security =           selinux_shm_alloc_security,
5713         .shm_free_security =            selinux_shm_free_security,
5714         .shm_associate =                selinux_shm_associate,
5715         .shm_shmctl =                   selinux_shm_shmctl,
5716         .shm_shmat =                    selinux_shm_shmat,
5717
5718         .sem_alloc_security =           selinux_sem_alloc_security,
5719         .sem_free_security =            selinux_sem_free_security,
5720         .sem_associate =                selinux_sem_associate,
5721         .sem_semctl =                   selinux_sem_semctl,
5722         .sem_semop =                    selinux_sem_semop,
5723
5724         .d_instantiate =                selinux_d_instantiate,
5725
5726         .getprocattr =                  selinux_getprocattr,
5727         .setprocattr =                  selinux_setprocattr,
5728
5729         .ismaclabel =                   selinux_ismaclabel,
5730         .secid_to_secctx =              selinux_secid_to_secctx,
5731         .secctx_to_secid =              selinux_secctx_to_secid,
5732         .release_secctx =               selinux_release_secctx,
5733         .inode_notifysecctx =           selinux_inode_notifysecctx,
5734         .inode_setsecctx =              selinux_inode_setsecctx,
5735         .inode_getsecctx =              selinux_inode_getsecctx,
5736
5737         .unix_stream_connect =          selinux_socket_unix_stream_connect,
5738         .unix_may_send =                selinux_socket_unix_may_send,
5739
5740         .socket_create =                selinux_socket_create,
5741         .socket_post_create =           selinux_socket_post_create,
5742         .socket_bind =                  selinux_socket_bind,
5743         .socket_connect =               selinux_socket_connect,
5744         .socket_listen =                selinux_socket_listen,
5745         .socket_accept =                selinux_socket_accept,
5746         .socket_sendmsg =               selinux_socket_sendmsg,
5747         .socket_recvmsg =               selinux_socket_recvmsg,
5748         .socket_getsockname =           selinux_socket_getsockname,
5749         .socket_getpeername =           selinux_socket_getpeername,
5750         .socket_getsockopt =            selinux_socket_getsockopt,
5751         .socket_setsockopt =            selinux_socket_setsockopt,
5752         .socket_shutdown =              selinux_socket_shutdown,
5753         .socket_sock_rcv_skb =          selinux_socket_sock_rcv_skb,
5754         .socket_getpeersec_stream =     selinux_socket_getpeersec_stream,
5755         .socket_getpeersec_dgram =      selinux_socket_getpeersec_dgram,
5756         .sk_alloc_security =            selinux_sk_alloc_security,
5757         .sk_free_security =             selinux_sk_free_security,
5758         .sk_clone_security =            selinux_sk_clone_security,
5759         .sk_getsecid =                  selinux_sk_getsecid,
5760         .sock_graft =                   selinux_sock_graft,
5761         .inet_conn_request =            selinux_inet_conn_request,
5762         .inet_csk_clone =               selinux_inet_csk_clone,
5763         .inet_conn_established =        selinux_inet_conn_established,
5764         .secmark_relabel_packet =       selinux_secmark_relabel_packet,
5765         .secmark_refcount_inc =         selinux_secmark_refcount_inc,
5766         .secmark_refcount_dec =         selinux_secmark_refcount_dec,
5767         .req_classify_flow =            selinux_req_classify_flow,
5768         .tun_dev_alloc_security =       selinux_tun_dev_alloc_security,
5769         .tun_dev_free_security =        selinux_tun_dev_free_security,
5770         .tun_dev_create =               selinux_tun_dev_create,
5771         .tun_dev_attach_queue =         selinux_tun_dev_attach_queue,
5772         .tun_dev_attach =               selinux_tun_dev_attach,
5773         .tun_dev_open =                 selinux_tun_dev_open,
5774         .skb_owned_by =                 selinux_skb_owned_by,
5775
5776 #ifdef CONFIG_SECURITY_NETWORK_XFRM
5777         .xfrm_policy_alloc_security =   selinux_xfrm_policy_alloc,
5778         .xfrm_policy_clone_security =   selinux_xfrm_policy_clone,
5779         .xfrm_policy_free_security =    selinux_xfrm_policy_free,
5780         .xfrm_policy_delete_security =  selinux_xfrm_policy_delete,
5781         .xfrm_state_alloc_security =    selinux_xfrm_state_alloc,
5782         .xfrm_state_free_security =     selinux_xfrm_state_free,
5783         .xfrm_state_delete_security =   selinux_xfrm_state_delete,
5784         .xfrm_policy_lookup =           selinux_xfrm_policy_lookup,
5785         .xfrm_state_pol_flow_match =    selinux_xfrm_state_pol_flow_match,
5786         .xfrm_decode_session =          selinux_xfrm_decode_session,
5787 #endif
5788
5789 #ifdef CONFIG_KEYS
5790         .key_alloc =                    selinux_key_alloc,
5791         .key_free =                     selinux_key_free,
5792         .key_permission =               selinux_key_permission,
5793         .key_getsecurity =              selinux_key_getsecurity,
5794 #endif
5795
5796 #ifdef CONFIG_AUDIT
5797         .audit_rule_init =              selinux_audit_rule_init,
5798         .audit_rule_known =             selinux_audit_rule_known,
5799         .audit_rule_match =             selinux_audit_rule_match,
5800         .audit_rule_free =              selinux_audit_rule_free,
5801 #endif
5802 };
5803
5804 static __init int selinux_init(void)
5805 {
5806         if (!security_module_enable(&selinux_ops)) {
5807                 selinux_enabled = 0;
5808                 return 0;
5809         }
5810
5811         if (!selinux_enabled) {
5812                 printk(KERN_INFO "SELinux:  Disabled at boot.\n");
5813                 return 0;
5814         }
5815
5816         printk(KERN_INFO "SELinux:  Initializing.\n");
5817
5818         /* Set the security state for the initial task. */
5819         cred_init_security();
5820
5821         default_noexec = !(VM_DATA_DEFAULT_FLAGS & VM_EXEC);
5822
5823         sel_inode_cache = kmem_cache_create("selinux_inode_security",
5824                                             sizeof(struct inode_security_struct),
5825                                             0, SLAB_PANIC, NULL);
5826         avc_init();
5827
5828         if (register_security(&selinux_ops))
5829                 panic("SELinux: Unable to register with kernel.\n");
5830
5831         if (selinux_enforcing)
5832                 printk(KERN_DEBUG "SELinux:  Starting in enforcing mode\n");
5833         else
5834                 printk(KERN_DEBUG "SELinux:  Starting in permissive mode\n");
5835
5836         return 0;
5837 }
5838
5839 static void delayed_superblock_init(struct super_block *sb, void *unused)
5840 {
5841         superblock_doinit(sb, NULL);
5842 }
5843
5844 void selinux_complete_init(void)
5845 {
5846         printk(KERN_DEBUG "SELinux:  Completing initialization.\n");
5847
5848         /* Set up any superblocks initialized prior to the policy load. */
5849         printk(KERN_DEBUG "SELinux:  Setting up existing superblocks.\n");
5850         iterate_supers(delayed_superblock_init, NULL);
5851 }
5852
5853 /* SELinux requires early initialization in order to label
5854    all processes and objects when they are created. */
5855 security_initcall(selinux_init);
5856
5857 #if defined(CONFIG_NETFILTER)
5858
5859 static struct nf_hook_ops selinux_ipv4_ops[] = {
5860         {
5861                 .hook =         selinux_ipv4_postroute,
5862                 .owner =        THIS_MODULE,
5863                 .pf =           NFPROTO_IPV4,
5864                 .hooknum =      NF_INET_POST_ROUTING,
5865                 .priority =     NF_IP_PRI_SELINUX_LAST,
5866         },
5867         {
5868                 .hook =         selinux_ipv4_forward,
5869                 .owner =        THIS_MODULE,
5870                 .pf =           NFPROTO_IPV4,
5871                 .hooknum =      NF_INET_FORWARD,
5872                 .priority =     NF_IP_PRI_SELINUX_FIRST,
5873         },
5874         {
5875                 .hook =         selinux_ipv4_output,
5876                 .owner =        THIS_MODULE,
5877                 .pf =           NFPROTO_IPV4,
5878                 .hooknum =      NF_INET_LOCAL_OUT,
5879                 .priority =     NF_IP_PRI_SELINUX_FIRST,
5880         }
5881 };
5882
5883 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
5884
5885 static struct nf_hook_ops selinux_ipv6_ops[] = {
5886         {
5887                 .hook =         selinux_ipv6_postroute,
5888                 .owner =        THIS_MODULE,
5889                 .pf =           NFPROTO_IPV6,
5890                 .hooknum =      NF_INET_POST_ROUTING,
5891                 .priority =     NF_IP6_PRI_SELINUX_LAST,
5892         },
5893         {
5894                 .hook =         selinux_ipv6_forward,
5895                 .owner =        THIS_MODULE,
5896                 .pf =           NFPROTO_IPV6,
5897                 .hooknum =      NF_INET_FORWARD,
5898                 .priority =     NF_IP6_PRI_SELINUX_FIRST,
5899         }
5900 };
5901
5902 #endif  /* IPV6 */
5903
5904 static int __init selinux_nf_ip_init(void)
5905 {
5906         int err = 0;
5907
5908         if (!selinux_enabled)
5909                 goto out;
5910
5911         printk(KERN_DEBUG "SELinux:  Registering netfilter hooks\n");
5912
5913         err = nf_register_hooks(selinux_ipv4_ops, ARRAY_SIZE(selinux_ipv4_ops));
5914         if (err)
5915                 panic("SELinux: nf_register_hooks for IPv4: error %d\n", err);
5916
5917 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
5918         err = nf_register_hooks(selinux_ipv6_ops, ARRAY_SIZE(selinux_ipv6_ops));
5919         if (err)
5920                 panic("SELinux: nf_register_hooks for IPv6: error %d\n", err);
5921 #endif  /* IPV6 */
5922
5923 out:
5924         return err;
5925 }
5926
5927 __initcall(selinux_nf_ip_init);
5928
5929 #ifdef CONFIG_SECURITY_SELINUX_DISABLE
5930 static void selinux_nf_ip_exit(void)
5931 {
5932         printk(KERN_DEBUG "SELinux:  Unregistering netfilter hooks\n");
5933
5934         nf_unregister_hooks(selinux_ipv4_ops, ARRAY_SIZE(selinux_ipv4_ops));
5935 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
5936         nf_unregister_hooks(selinux_ipv6_ops, ARRAY_SIZE(selinux_ipv6_ops));
5937 #endif  /* IPV6 */
5938 }
5939 #endif
5940
5941 #else /* CONFIG_NETFILTER */
5942
5943 #ifdef CONFIG_SECURITY_SELINUX_DISABLE
5944 #define selinux_nf_ip_exit()
5945 #endif
5946
5947 #endif /* CONFIG_NETFILTER */
5948
5949 #ifdef CONFIG_SECURITY_SELINUX_DISABLE
5950 static int selinux_disabled;
5951
5952 int selinux_disable(void)
5953 {
5954         if (ss_initialized) {
5955                 /* Not permitted after initial policy load. */
5956                 return -EINVAL;
5957         }
5958
5959         if (selinux_disabled) {
5960                 /* Only do this once. */
5961                 return -EINVAL;
5962         }
5963
5964         printk(KERN_INFO "SELinux:  Disabled at runtime.\n");
5965
5966         selinux_disabled = 1;
5967         selinux_enabled = 0;
5968
5969         reset_security_ops();
5970
5971         /* Try to destroy the avc node cache */
5972         avc_disable();
5973
5974         /* Unregister netfilter hooks. */
5975         selinux_nf_ip_exit();
5976
5977         /* Unregister selinuxfs. */
5978         exit_sel_fs();
5979
5980         return 0;
5981 }
5982 #endif