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/tcp.h>            /* struct or_callable used in sock_rcv_skb */
  55 #include <net/net_namespace.h>
  56 #include <net/netlabel.h>
  57 #include <linux/uaccess.h>
  58 #include <asm/ioctls.h>
  59 #include <linux/atomic.h>
  60 #include <linux/bitops.h>
  61 #include <linux/interrupt.h>
  62 #include <linux/netdevice.h>    /* for network interface checks */
  63 #include <linux/netlink.h>
  64 #include <linux/tcp.h>
  65 #include <linux/udp.h>
  66 #include <linux/dccp.h>
  67 #include <linux/quota.h>
  68 #include <linux/un.h>           /* for Unix socket types */
  69 #include <net/af_unix.h>        /* for Unix socket types */
  70 #include <linux/parser.h>
  71 #include <linux/nfs_mount.h>
  72 #include <net/ipv6.h>
  73 #include <linux/hugetlb.h>
  74 #include <linux/personality.h>
  75 #include <linux/audit.h>
  76 #include <linux/string.h>
  77 #include <linux/selinux.h>
  78 #include <linux/mutex.h>
  79 #include <linux/posix-timers.h>
  80 #include <linux/syslog.h>
  81 #include <linux/user_namespace.h>
  82 #include <linux/export.h>
  83 #include <linux/msg.h>
  84 #include <linux/shm.h>
  85
  86 #include "avc.h"
  87 #include "objsec.h"
  88 #include "netif.h"
  89 #include "netnode.h"
  90 #include "netport.h"
  91 #include "xfrm.h"
  92 #include "netlabel.h"
  93 #include "audit.h"
  94 #include "avc_ss.h"
  95
  96 #define NUM_SEL_MNT_OPTS 5
  97
  98 extern struct security_operations *security_ops;
  99
 100 /* SECMARK reference count */
 101 static atomic_t selinux_secmark_refcount = ATOMIC_INIT(0);
 102
 103 #ifdef CONFIG_SECURITY_SELINUX_DEVELOP
 104 int selinux_enforcing;
 105
 106 static int __init enforcing_setup(char *str)
 107 {
 108         unsigned long enforcing;
 109         if (!strict_strtoul(str, 0, &enforcing))
 110                 selinux_enforcing = enforcing ? 1 : 0;
 111         return 1;
 112 }
 113 __setup("enforcing=", enforcing_setup);
 114 #endif
 115
 116 #ifdef CONFIG_SECURITY_SELINUX_BOOTPARAM
 117 int selinux_enabled = CONFIG_SECURITY_SELINUX_BOOTPARAM_VALUE;
 118
 119 static int __init selinux_enabled_setup(char *str)
 120 {
 121         unsigned long enabled;
 122         if (!strict_strtoul(str, 0, &enabled))
 123                 selinux_enabled = enabled ? 1 : 0;
 124         return 1;
 125 }
 126 __setup("selinux=", selinux_enabled_setup);
 127 #else
 128 int selinux_enabled = 1;
 129 #endif
 130
 131 static struct kmem_cache *sel_inode_cache;
 132
 133 /**
 134  * selinux_secmark_enabled - Check to see if SECMARK is currently enabled
 135  *
 136  * Description:
 137  * This function checks the SECMARK reference counter to see if any SECMARK
 138  * targets are currently configured, if the reference counter is greater than
 139  * zero SECMARK is considered to be enabled.  Returns true (1) if SECMARK is
 140  * enabled, false (0) if SECMARK is disabled.
 141  *
 142  */
 143 static int selinux_secmark_enabled(void)
 144 {
 145         return (atomic_read(&selinux_secmark_refcount) > 0);
 146 }
 147
 148 /*
 149  * initialise the security for the init task
 150  */
 151 static void cred_init_security(void)
 152 {
 153         struct cred *cred = (struct cred *) current->real_cred;
 154         struct task_security_struct *tsec;
 155
 156         tsec = kzalloc(sizeof(struct task_security_struct), GFP_KERNEL);
 157         if (!tsec)
 158                 panic("SELinux:  Failed to initialize initial task.\n");
 159
 160         tsec->osid = tsec->sid = SECINITSID_KERNEL;
 161         cred->security = tsec;
 162 }
 163
 164 /*
 165  * get the security ID of a set of credentials
 166  */
 167 static inline u32 cred_sid(const struct cred *cred)
 168 {
 169         const struct task_security_struct *tsec;
 170
 171         tsec = cred->security;
 172         return tsec->sid;
 173 }
 174
 175 /*
 176  * get the objective security ID of a task
 177  */
 178 static inline u32 task_sid(const struct task_struct *task)
 179 {
 180         u32 sid;
 181
 182         rcu_read_lock();
 183         sid = cred_sid(__task_cred(task));
 184         rcu_read_unlock();
 185         return sid;
 186 }
 187
 188 /*
 189  * get the subjective security ID of the current task
 190  */
 191 static inline u32 current_sid(void)
 192 {
 193         const struct task_security_struct *tsec = current_security();
 194
 195         return tsec->sid;
 196 }
 197
 198 /* Allocate and free functions for each kind of security blob. */
 199
 200 static int inode_alloc_security(struct inode *inode)
 201 {
 202         struct inode_security_struct *isec;
 203         u32 sid = current_sid();
 204
 205         isec = kmem_cache_zalloc(sel_inode_cache, GFP_NOFS);
 206         if (!isec)
 207                 return -ENOMEM;
 208
 209         mutex_init(&isec->lock);
 210         INIT_LIST_HEAD(&isec->list);
 211         isec->inode = inode;
 212         isec->sid = SECINITSID_UNLABELED;
 213         isec->sclass = SECCLASS_FILE;
 214         isec->task_sid = sid;
 215         inode->i_security = isec;
 216
 217         return 0;
 218 }
 219
 220 static void inode_free_security(struct inode *inode)
 221 {
 222         struct inode_security_struct *isec = inode->i_security;
 223         struct superblock_security_struct *sbsec = inode->i_sb->s_security;
 224
 225         spin_lock(&sbsec->isec_lock);
 226         if (!list_empty(&isec->list))
 227                 list_del_init(&isec->list);
 228         spin_unlock(&sbsec->isec_lock);
 229
 230         inode->i_security = NULL;
 231         kmem_cache_free(sel_inode_cache, isec);
 232 }
 233
 234 static int file_alloc_security(struct file *file)
 235 {
 236         struct file_security_struct *fsec;
 237         u32 sid = current_sid();
 238
 239         fsec = kzalloc(sizeof(struct file_security_struct), GFP_KERNEL);
 240         if (!fsec)
 241                 return -ENOMEM;
 242
 243         fsec->sid = sid;
 244         fsec->fown_sid = sid;
 245         file->f_security = fsec;
 246
 247         return 0;
 248 }
 249
 250 static void file_free_security(struct file *file)
 251 {
 252         struct file_security_struct *fsec = file->f_security;
 253         file->f_security = NULL;
 254         kfree(fsec);
 255 }
 256
 257 static int superblock_alloc_security(struct super_block *sb)
 258 {
 259         struct superblock_security_struct *sbsec;
 260
 261         sbsec = kzalloc(sizeof(struct superblock_security_struct), GFP_KERNEL);
 262         if (!sbsec)
 263                 return -ENOMEM;
 264
 265         mutex_init(&sbsec->lock);
 266         INIT_LIST_HEAD(&sbsec->isec_head);
 267         spin_lock_init(&sbsec->isec_lock);
 268         sbsec->sb = sb;
 269         sbsec->sid = SECINITSID_UNLABELED;
 270         sbsec->def_sid = SECINITSID_FILE;
 271         sbsec->mntpoint_sid = SECINITSID_UNLABELED;
 272         sb->s_security = sbsec;
 273
 274         return 0;
 275 }
 276
 277 static void superblock_free_security(struct super_block *sb)
 278 {
 279         struct superblock_security_struct *sbsec = sb->s_security;
 280         sb->s_security = NULL;
 281         kfree(sbsec);
 282 }
 283
 284 /* The file system's label must be initialized prior to use. */
 285
 286 static const char *labeling_behaviors[6] = {
 287         "uses xattr",
 288         "uses transition SIDs",
 289         "uses task SIDs",
 290         "uses genfs_contexts",
 291         "not configured for labeling",
 292         "uses mountpoint labeling",
 293 };
 294
 295 static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dentry);
 296
 297 static inline int inode_doinit(struct inode *inode)
 298 {
 299         return inode_doinit_with_dentry(inode, NULL);
 300 }
 301
 302 enum {
 303         Opt_error = -1,
 304         Opt_context = 1,
 305         Opt_fscontext = 2,
 306         Opt_defcontext = 3,
 307         Opt_rootcontext = 4,
 308         Opt_labelsupport = 5,
 309 };
 310
 311 static const match_table_t tokens = {
 312         {Opt_context, CONTEXT_STR "%s"},
 313         {Opt_fscontext, FSCONTEXT_STR "%s"},
 314         {Opt_defcontext, DEFCONTEXT_STR "%s"},
 315         {Opt_rootcontext, ROOTCONTEXT_STR "%s"},
 316         {Opt_labelsupport, LABELSUPP_STR},
 317         {Opt_error, NULL},
 318 };
 319
 320 #define SEL_MOUNT_FAIL_MSG "SELinux:  duplicate or incompatible mount options\n"
 321
 322 static int may_context_mount_sb_relabel(u32 sid,
 323                         struct superblock_security_struct *sbsec,
 324                         const struct cred *cred)
 325 {
 326         const struct task_security_struct *tsec = cred->security;
 327         int rc;
 328
 329         rc = avc_has_perm(tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM,
 330                           FILESYSTEM__RELABELFROM, NULL);
 331         if (rc)
 332                 return rc;
 333
 334         rc = avc_has_perm(tsec->sid, sid, SECCLASS_FILESYSTEM,
 335                           FILESYSTEM__RELABELTO, NULL);
 336         return rc;
 337 }
 338
 339 static int may_context_mount_inode_relabel(u32 sid,
 340                         struct superblock_security_struct *sbsec,
 341                         const struct cred *cred)
 342 {
 343         const struct task_security_struct *tsec = cred->security;
 344         int rc;
 345         rc = avc_has_perm(tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM,
 346                           FILESYSTEM__RELABELFROM, NULL);
 347         if (rc)
 348                 return rc;
 349
 350         rc = avc_has_perm(sid, sbsec->sid, SECCLASS_FILESYSTEM,
 351                           FILESYSTEM__ASSOCIATE, NULL);
 352         return rc;
 353 }
 354
 355 static int sb_finish_set_opts(struct super_block *sb)
 356 {
 357         struct superblock_security_struct *sbsec = sb->s_security;
 358         struct dentry *root = sb->s_root;
 359         struct inode *root_inode = root->d_inode;
 360         int rc = 0;
 361
 362         if (sbsec->behavior == SECURITY_FS_USE_XATTR) {
 363                 /* Make sure that the xattr handler exists and that no
 364                    error other than -ENODATA is returned by getxattr on
 365                    the root directory.  -ENODATA is ok, as this may be
 366                    the first boot of the SELinux kernel before we have
 367                    assigned xattr values to the filesystem. */
 368                 if (!root_inode->i_op->getxattr) {
 369                         printk(KERN_WARNING "SELinux: (dev %s, type %s) has no "
 370                                "xattr support\n", sb->s_id, sb->s_type->name);
 371                         rc = -EOPNOTSUPP;
 372                         goto out;
 373                 }
 374                 rc = root_inode->i_op->getxattr(root, XATTR_NAME_SELINUX, NULL, 0);
 375                 if (rc < 0 && rc != -ENODATA) {
 376                         if (rc == -EOPNOTSUPP)
 377                                 printk(KERN_WARNING "SELinux: (dev %s, type "
 378                                        "%s) has no security xattr handler\n",
 379                                        sb->s_id, sb->s_type->name);
 380                         else
 381                                 printk(KERN_WARNING "SELinux: (dev %s, type "
 382                                        "%s) getxattr errno %d\n", sb->s_id,
 383                                        sb->s_type->name, -rc);
 384                         goto out;
 385                 }
 386         }
 387
 388         sbsec->flags |= (SE_SBINITIALIZED | SE_SBLABELSUPP);
 389
 390         if (sbsec->behavior > ARRAY_SIZE(labeling_behaviors))
 391                 printk(KERN_ERR "SELinux: initialized (dev %s, type %s), unknown behavior\n",
 392                        sb->s_id, sb->s_type->name);
 393         else
 394                 printk(KERN_DEBUG "SELinux: initialized (dev %s, type %s), %s\n",
 395                        sb->s_id, sb->s_type->name,
 396                        labeling_behaviors[sbsec->behavior-1]);
 397
 398         if (sbsec->behavior == SECURITY_FS_USE_GENFS ||
 399             sbsec->behavior == SECURITY_FS_USE_MNTPOINT ||
 400             sbsec->behavior == SECURITY_FS_USE_NONE ||
 401             sbsec->behavior > ARRAY_SIZE(labeling_behaviors))
 402                 sbsec->flags &= ~SE_SBLABELSUPP;
 403
 404         /* Special handling for sysfs. Is genfs but also has setxattr handler*/
 405         if (strncmp(sb->s_type->name, "sysfs", sizeof("sysfs")) == 0)
 406                 sbsec->flags |= SE_SBLABELSUPP;
 407
 408         /* Initialize the root inode. */
 409         rc = inode_doinit_with_dentry(root_inode, root);
 410
 411         /* Initialize any other inodes associated with the superblock, e.g.
 412            inodes created prior to initial policy load or inodes created
 413            during get_sb by a pseudo filesystem that directly
 414            populates itself. */
 415         spin_lock(&sbsec->isec_lock);
 416 next_inode:
 417         if (!list_empty(&sbsec->isec_head)) {
 418                 struct inode_security_struct *isec =
 419                                 list_entry(sbsec->isec_head.next,
 420                                            struct inode_security_struct, list);
 421                 struct inode *inode = isec->inode;
 422                 spin_unlock(&sbsec->isec_lock);
 423                 inode = igrab(inode);
 424                 if (inode) {
 425                         if (!IS_PRIVATE(inode))
 426                                 inode_doinit(inode);
 427                         iput(inode);
 428                 }
 429                 spin_lock(&sbsec->isec_lock);
 430                 list_del_init(&isec->list);
 431                 goto next_inode;
 432         }
 433         spin_unlock(&sbsec->isec_lock);
 434 out:
 435         return rc;
 436 }
 437
 438 /*
 439  * This function should allow an FS to ask what it's mount security
 440  * options were so it can use those later for submounts, displaying
 441  * mount options, or whatever.
 442  */
 443 static int selinux_get_mnt_opts(const struct super_block *sb,
 444                                 struct security_mnt_opts *opts)
 445 {
 446         int rc = 0, i;
 447         struct superblock_security_struct *sbsec = sb->s_security;
 448         char *context = NULL;
 449         u32 len;
 450         char tmp;
 451
 452         security_init_mnt_opts(opts);
 453
 454         if (!(sbsec->flags & SE_SBINITIALIZED))
 455                 return -EINVAL;
 456
 457         if (!ss_initialized)
 458                 return -EINVAL;
 459
 460         tmp = sbsec->flags & SE_MNTMASK;
 461         /* count the number of mount options for this sb */
 462         for (i = 0; i < 8; i++) {
 463                 if (tmp & 0x01)
 464                         opts->num_mnt_opts++;
 465                 tmp >>= 1;
 466         }
 467         /* Check if the Label support flag is set */
 468         if (sbsec->flags & SE_SBLABELSUPP)
 469                 opts->num_mnt_opts++;
 470
 471         opts->mnt_opts = kcalloc(opts->num_mnt_opts, sizeof(char *), GFP_ATOMIC);
 472         if (!opts->mnt_opts) {
 473                 rc = -ENOMEM;
 474                 goto out_free;
 475         }
 476
 477         opts->mnt_opts_flags = kcalloc(opts->num_mnt_opts, sizeof(int), GFP_ATOMIC);
 478         if (!opts->mnt_opts_flags) {
 479                 rc = -ENOMEM;
 480                 goto out_free;
 481         }
 482
 483         i = 0;
 484         if (sbsec->flags & FSCONTEXT_MNT) {
 485                 rc = security_sid_to_context(sbsec->sid, &context, &len);
 486                 if (rc)
 487                         goto out_free;
 488                 opts->mnt_opts[i] = context;
 489                 opts->mnt_opts_flags[i++] = FSCONTEXT_MNT;
 490         }
 491         if (sbsec->flags & CONTEXT_MNT) {
 492                 rc = security_sid_to_context(sbsec->mntpoint_sid, &context, &len);
 493                 if (rc)
 494                         goto out_free;
 495                 opts->mnt_opts[i] = context;
 496                 opts->mnt_opts_flags[i++] = CONTEXT_MNT;
 497         }
 498         if (sbsec->flags & DEFCONTEXT_MNT) {
 499                 rc = security_sid_to_context(sbsec->def_sid, &context, &len);
 500                 if (rc)
 501                         goto out_free;
 502                 opts->mnt_opts[i] = context;
 503                 opts->mnt_opts_flags[i++] = DEFCONTEXT_MNT;
 504         }
 505         if (sbsec->flags & ROOTCONTEXT_MNT) {
 506                 struct inode *root = sbsec->sb->s_root->d_inode;
 507                 struct inode_security_struct *isec = root->i_security;
 508
 509                 rc = security_sid_to_context(isec->sid, &context, &len);
 510                 if (rc)
 511                         goto out_free;
 512                 opts->mnt_opts[i] = context;
 513                 opts->mnt_opts_flags[i++] = ROOTCONTEXT_MNT;
 514         }
 515         if (sbsec->flags & SE_SBLABELSUPP) {
 516                 opts->mnt_opts[i] = NULL;
 517                 opts->mnt_opts_flags[i++] = SE_SBLABELSUPP;
 518         }
 519
 520         BUG_ON(i != opts->num_mnt_opts);
 521
 522         return 0;
 523
 524 out_free:
 525         security_free_mnt_opts(opts);
 526         return rc;
 527 }
 528
 529 static int bad_option(struct superblock_security_struct *sbsec, char flag,
 530                       u32 old_sid, u32 new_sid)
 531 {
 532         char mnt_flags = sbsec->flags & SE_MNTMASK;
 533
 534         /* check if the old mount command had the same options */
 535         if (sbsec->flags & SE_SBINITIALIZED)
 536                 if (!(sbsec->flags & flag) ||
 537                     (old_sid != new_sid))
 538                         return 1;
 539
 540         /* check if we were passed the same options twice,
 541          * aka someone passed context=a,context=b
 542          */
 543         if (!(sbsec->flags & SE_SBINITIALIZED))
 544                 if (mnt_flags & flag)
 545                         return 1;
 546         return 0;
 547 }
 548
 549 /*
 550  * Allow filesystems with binary mount data to explicitly set mount point
 551  * labeling information.
 552  */
 553 static int selinux_set_mnt_opts(struct super_block *sb,
 554                                 struct security_mnt_opts *opts)
 555 {
 556         const struct cred *cred = current_cred();
 557         int rc = 0, i;
 558         struct superblock_security_struct *sbsec = sb->s_security;
 559         const char *name = sb->s_type->name;
 560         struct inode *inode = sbsec->sb->s_root->d_inode;
 561         struct inode_security_struct *root_isec = inode->i_security;
 562         u32 fscontext_sid = 0, context_sid = 0, rootcontext_sid = 0;
 563         u32 defcontext_sid = 0;
 564         char **mount_options = opts->mnt_opts;
 565         int *flags = opts->mnt_opts_flags;
 566         int num_opts = opts->num_mnt_opts;
 567
 568         mutex_lock(&sbsec->lock);
 569
 570         if (!ss_initialized) {
 571                 if (!num_opts) {
 572                         /* Defer initialization until selinux_complete_init,
 573                            after the initial policy is loaded and the security
 574                            server is ready to handle calls. */
 575                         goto out;
 576                 }
 577                 rc = -EINVAL;
 578                 printk(KERN_WARNING "SELinux: Unable to set superblock options "
 579                         "before the security server is initialized\n");
 580                 goto out;
 581         }
 582
 583         /*
 584          * Binary mount data FS will come through this function twice.  Once
 585          * from an explicit call and once from the generic calls from the vfs.
 586          * Since the generic VFS calls will not contain any security mount data
 587          * we need to skip the double mount verification.
 588          *
 589          * This does open a hole in which we will not notice if the first
 590          * mount using this sb set explict options and a second mount using
 591          * this sb does not set any security options.  (The first options
 592          * will be used for both mounts)
 593          */
 594         if ((sbsec->flags & SE_SBINITIALIZED) && (sb->s_type->fs_flags & FS_BINARY_MOUNTDATA)
 595             && (num_opts == 0))
 596                 goto out;
 597
 598         /*
 599          * parse the mount options, check if they are valid sids.
 600          * also check if someone is trying to mount the same sb more
 601          * than once with different security options.
 602          */
 603         for (i = 0; i < num_opts; i++) {
 604                 u32 sid;
 605
 606                 if (flags[i] == SE_SBLABELSUPP)
 607                         continue;
 608                 rc = security_context_to_sid(mount_options[i],
 609                                              strlen(mount_options[i]), &sid);
 610                 if (rc) {
 611                         printk(KERN_WARNING "SELinux: security_context_to_sid"
 612                                "(%s) failed for (dev %s, type %s) errno=%d\n",
 613                                mount_options[i], sb->s_id, name, rc);
 614                         goto out;
 615                 }
 616                 switch (flags[i]) {
 617                 case FSCONTEXT_MNT:
 618                         fscontext_sid = sid;
 619
 620                         if (bad_option(sbsec, FSCONTEXT_MNT, sbsec->sid,
 621                                         fscontext_sid))
 622                                 goto out_double_mount;
 623
 624                         sbsec->flags |= FSCONTEXT_MNT;
 625                         break;
 626                 case CONTEXT_MNT:
 627                         context_sid = sid;
 628
 629                         if (bad_option(sbsec, CONTEXT_MNT, sbsec->mntpoint_sid,
 630                                         context_sid))
 631                                 goto out_double_mount;
 632
 633                         sbsec->flags |= CONTEXT_MNT;
 634                         break;
 635                 case ROOTCONTEXT_MNT:
 636                         rootcontext_sid = sid;
 637
 638                         if (bad_option(sbsec, ROOTCONTEXT_MNT, root_isec->sid,
 639                                         rootcontext_sid))
 640                                 goto out_double_mount;
 641
 642                         sbsec->flags |= ROOTCONTEXT_MNT;
 643
 644                         break;
 645                 case DEFCONTEXT_MNT:
 646                         defcontext_sid = sid;
 647
 648                         if (bad_option(sbsec, DEFCONTEXT_MNT, sbsec->def_sid,
 649                                         defcontext_sid))
 650                                 goto out_double_mount;
 651
 652                         sbsec->flags |= DEFCONTEXT_MNT;
 653
 654                         break;
 655                 default:
 656                         rc = -EINVAL;
 657                         goto out;
 658                 }
 659         }
 660
 661         if (sbsec->flags & SE_SBINITIALIZED) {
 662                 /* previously mounted with options, but not on this attempt? */
 663                 if ((sbsec->flags & SE_MNTMASK) && !num_opts)
 664                         goto out_double_mount;
 665                 rc = 0;
 666                 goto out;
 667         }
 668
 669         if (strcmp(sb->s_type->name, "proc") == 0)
 670                 sbsec->flags |= SE_SBPROC;
 671
 672         /* Determine the labeling behavior to use for this filesystem type. */
 673         rc = security_fs_use((sbsec->flags & SE_SBPROC) ? "proc" : sb->s_type->name, &sbsec->behavior, &sbsec->sid);
 674         if (rc) {
 675                 printk(KERN_WARNING "%s: security_fs_use(%s) returned %d\n",
 676                        __func__, sb->s_type->name, rc);
 677                 goto out;
 678         }
 679
 680         /* sets the context of the superblock for the fs being mounted. */
 681         if (fscontext_sid) {
 682                 rc = may_context_mount_sb_relabel(fscontext_sid, sbsec, cred);
 683                 if (rc)
 684                         goto out;
 685
 686                 sbsec->sid = fscontext_sid;
 687         }
 688
 689         /*
 690          * Switch to using mount point labeling behavior.
 691          * sets the label used on all file below the mountpoint, and will set
 692          * the superblock context if not already set.
 693          */
 694         if (context_sid) {
 695                 if (!fscontext_sid) {
 696                         rc = may_context_mount_sb_relabel(context_sid, sbsec,
 697                                                           cred);
 698                         if (rc)
 699                                 goto out;
 700                         sbsec->sid = context_sid;
 701                 } else {
 702                         rc = may_context_mount_inode_relabel(context_sid, sbsec,
 703                                                              cred);
 704                         if (rc)
 705                                 goto out;
 706                 }
 707                 if (!rootcontext_sid)
 708                         rootcontext_sid = context_sid;
 709
 710                 sbsec->mntpoint_sid = context_sid;
 711                 sbsec->behavior = SECURITY_FS_USE_MNTPOINT;
 712         }
 713
 714         if (rootcontext_sid) {
 715                 rc = may_context_mount_inode_relabel(rootcontext_sid, sbsec,
 716                                                      cred);
 717                 if (rc)
 718                         goto out;
 719
 720                 root_isec->sid = rootcontext_sid;
 721                 root_isec->initialized = 1;
 722         }
 723
 724         if (defcontext_sid) {
 725                 if (sbsec->behavior != SECURITY_FS_USE_XATTR) {
 726                         rc = -EINVAL;
 727                         printk(KERN_WARNING "SELinux: defcontext option is "
 728                                "invalid for this filesystem type\n");
 729                         goto out;
 730                 }
 731
 732                 if (defcontext_sid != sbsec->def_sid) {
 733                         rc = may_context_mount_inode_relabel(defcontext_sid,
 734                                                              sbsec, cred);
 735                         if (rc)
 736                                 goto out;
 737                 }
 738
 739                 sbsec->def_sid = defcontext_sid;
 740         }
 741
 742         rc = sb_finish_set_opts(sb);
 743 out:
 744         mutex_unlock(&sbsec->lock);
 745         return rc;
 746 out_double_mount:
 747         rc = -EINVAL;
 748         printk(KERN_WARNING "SELinux: mount invalid.  Same superblock, different "
 749                "security settings for (dev %s, type %s)\n", sb->s_id, name);
 750         goto out;
 751 }
 752
 753 static void selinux_sb_clone_mnt_opts(const struct super_block *oldsb,
 754                                         struct super_block *newsb)
 755 {
 756         const struct superblock_security_struct *oldsbsec = oldsb->s_security;
 757         struct superblock_security_struct *newsbsec = newsb->s_security;
 758
 759         int set_fscontext =     (oldsbsec->flags & FSCONTEXT_MNT);
 760         int set_context =       (oldsbsec->flags & CONTEXT_MNT);
 761         int set_rootcontext =   (oldsbsec->flags & ROOTCONTEXT_MNT);
 762
 763         /*
 764          * if the parent was able to be mounted it clearly had no special lsm
 765          * mount options.  thus we can safely deal with this superblock later
 766          */
 767         if (!ss_initialized)
 768                 return;
 769
 770         /* how can we clone if the old one wasn't set up?? */
 771         BUG_ON(!(oldsbsec->flags & SE_SBINITIALIZED));
 772
 773         /* if fs is reusing a sb, just let its options stand... */
 774         if (newsbsec->flags & SE_SBINITIALIZED)
 775                 return;
 776
 777         mutex_lock(&newsbsec->lock);
 778
 779         newsbsec->flags = oldsbsec->flags;
 780
 781         newsbsec->sid = oldsbsec->sid;
 782         newsbsec->def_sid = oldsbsec->def_sid;
 783         newsbsec->behavior = oldsbsec->behavior;
 784
 785         if (set_context) {
 786                 u32 sid = oldsbsec->mntpoint_sid;
 787
 788                 if (!set_fscontext)
 789                         newsbsec->sid = sid;
 790                 if (!set_rootcontext) {
 791                         struct inode *newinode = newsb->s_root->d_inode;
 792                         struct inode_security_struct *newisec = newinode->i_security;
 793                         newisec->sid = sid;
 794                 }
 795                 newsbsec->mntpoint_sid = sid;
 796         }
 797         if (set_rootcontext) {
 798                 const struct inode *oldinode = oldsb->s_root->d_inode;
 799                 const struct inode_security_struct *oldisec = oldinode->i_security;
 800                 struct inode *newinode = newsb->s_root->d_inode;
 801                 struct inode_security_struct *newisec = newinode->i_security;
 802
 803                 newisec->sid = oldisec->sid;
 804         }
 805
 806         sb_finish_set_opts(newsb);
 807         mutex_unlock(&newsbsec->lock);
 808 }
 809
 810 static int selinux_parse_opts_str(char *options,
 811                                   struct security_mnt_opts *opts)
 812 {
 813         char *p;
 814         char *context = NULL, *defcontext = NULL;
 815         char *fscontext = NULL, *rootcontext = NULL;
 816         int rc, num_mnt_opts = 0;
 817
 818         opts->num_mnt_opts = 0;
 819
 820         /* Standard string-based options. */
 821         while ((p = strsep(&options, "|")) != NULL) {
 822                 int token;
 823                 substring_t args[MAX_OPT_ARGS];
 824
 825                 if (!*p)
 826                         continue;
 827
 828                 token = match_token(p, tokens, args);
 829
 830                 switch (token) {
 831                 case Opt_context:
 832                         if (context || defcontext) {
 833                                 rc = -EINVAL;
 834                                 printk(KERN_WARNING SEL_MOUNT_FAIL_MSG);
 835                                 goto out_err;
 836                         }
 837                         context = match_strdup(&args[0]);
 838                         if (!context) {
 839                                 rc = -ENOMEM;
 840                                 goto out_err;
 841                         }
 842                         break;
 843
 844                 case Opt_fscontext:
 845                         if (fscontext) {
 846                                 rc = -EINVAL;
 847                                 printk(KERN_WARNING SEL_MOUNT_FAIL_MSG);
 848                                 goto out_err;
 849                         }
 850                         fscontext = match_strdup(&args[0]);
 851                         if (!fscontext) {
 852                                 rc = -ENOMEM;
 853                                 goto out_err;
 854                         }
 855                         break;
 856
 857                 case Opt_rootcontext:
 858                         if (rootcontext) {
 859                                 rc = -EINVAL;
 860                                 printk(KERN_WARNING SEL_MOUNT_FAIL_MSG);
 861                                 goto out_err;
 862                         }
 863                         rootcontext = match_strdup(&args[0]);
 864                         if (!rootcontext) {
 865                                 rc = -ENOMEM;
 866                                 goto out_err;
 867                         }
 868                         break;
 869
 870                 case Opt_defcontext:
 871                         if (context || defcontext) {
 872                                 rc = -EINVAL;
 873                                 printk(KERN_WARNING SEL_MOUNT_FAIL_MSG);
 874                                 goto out_err;
 875                         }
 876                         defcontext = match_strdup(&args[0]);
 877                         if (!defcontext) {
 878                                 rc = -ENOMEM;
 879                                 goto out_err;
 880                         }
 881                         break;
 882                 case Opt_labelsupport:
 883                         break;
 884                 default:
 885                         rc = -EINVAL;
 886                         printk(KERN_WARNING "SELinux:  unknown mount option\n");
 887                         goto out_err;
 888
 889                 }
 890         }
 891
 892         rc = -ENOMEM;
 893         opts->mnt_opts = kcalloc(NUM_SEL_MNT_OPTS, sizeof(char *), GFP_ATOMIC);
 894         if (!opts->mnt_opts)
 895                 goto out_err;
 896
 897         opts->mnt_opts_flags = kcalloc(NUM_SEL_MNT_OPTS, sizeof(int), GFP_ATOMIC);
 898         if (!opts->mnt_opts_flags) {
 899                 kfree(opts->mnt_opts);
 900                 goto out_err;
 901         }
 902
 903         if (fscontext) {
 904                 opts->mnt_opts[num_mnt_opts] = fscontext;
 905                 opts->mnt_opts_flags[num_mnt_opts++] = FSCONTEXT_MNT;
 906         }
 907         if (context) {
 908                 opts->mnt_opts[num_mnt_opts] = context;
 909                 opts->mnt_opts_flags[num_mnt_opts++] = CONTEXT_MNT;
 910         }
 911         if (rootcontext) {
 912                 opts->mnt_opts[num_mnt_opts] = rootcontext;
 913                 opts->mnt_opts_flags[num_mnt_opts++] = ROOTCONTEXT_MNT;
 914         }
 915         if (defcontext) {
 916                 opts->mnt_opts[num_mnt_opts] = defcontext;
 917                 opts->mnt_opts_flags[num_mnt_opts++] = DEFCONTEXT_MNT;
 918         }
 919
 920         opts->num_mnt_opts = num_mnt_opts;
 921         return 0;
 922
 923 out_err:
 924         kfree(context);
 925         kfree(defcontext);
 926         kfree(fscontext);
 927         kfree(rootcontext);
 928         return rc;
 929 }
 930 /*
 931  * string mount options parsing and call set the sbsec
 932  */
 933 static int superblock_doinit(struct super_block *sb, void *data)
 934 {
 935         int rc = 0;
 936         char *options = data;
 937         struct security_mnt_opts opts;
 938
 939         security_init_mnt_opts(&opts);
 940
 941         if (!data)
 942                 goto out;
 943
 944         BUG_ON(sb->s_type->fs_flags & FS_BINARY_MOUNTDATA);
 945
 946         rc = selinux_parse_opts_str(options, &opts);
 947         if (rc)
 948                 goto out_err;
 949
 950 out:
 951         rc = selinux_set_mnt_opts(sb, &opts);
 952
 953 out_err:
 954         security_free_mnt_opts(&opts);
 955         return rc;
 956 }
 957
 958 static void selinux_write_opts(struct seq_file *m,
 959                                struct security_mnt_opts *opts)
 960 {
 961         int i;
 962         char *prefix;
 963
 964         for (i = 0; i < opts->num_mnt_opts; i++) {
 965                 char *has_comma;
 966
 967                 if (opts->mnt_opts[i])
 968                         has_comma = strchr(opts->mnt_opts[i], ',');
 969                 else
 970                         has_comma = NULL;
 971
 972                 switch (opts->mnt_opts_flags[i]) {
 973                 case CONTEXT_MNT:
 974                         prefix = CONTEXT_STR;
 975                         break;
 976                 case FSCONTEXT_MNT:
 977                         prefix = FSCONTEXT_STR;
 978                         break;
 979                 case ROOTCONTEXT_MNT:
 980                         prefix = ROOTCONTEXT_STR;
 981                         break;
 982                 case DEFCONTEXT_MNT:
 983                         prefix = DEFCONTEXT_STR;
 984                         break;
 985                 case SE_SBLABELSUPP:
 986                         seq_putc(m, ',');
 987                         seq_puts(m, LABELSUPP_STR);
 988                         continue;
 989                 default:
 990                         BUG();
 991                         return;
 992                 };
 993                 /* we need a comma before each option */
 994                 seq_putc(m, ',');
 995                 seq_puts(m, prefix);
 996                 if (has_comma)
 997                         seq_putc(m, '\"');
 998                 seq_puts(m, opts->mnt_opts[i]);
 999                 if (has_comma)
1000                         seq_putc(m, '\"');
1001         }
1002 }
1003
1004 static int selinux_sb_show_options(struct seq_file *m, struct super_block *sb)
1005 {
1006         struct security_mnt_opts opts;
1007         int rc;
1008
1009         rc = selinux_get_mnt_opts(sb, &opts);
1010         if (rc) {
1011                 /* before policy load we may get EINVAL, don't show anything */
1012                 if (rc == -EINVAL)
1013                         rc = 0;
1014                 return rc;
1015         }
1016
1017         selinux_write_opts(m, &opts);
1018
1019         security_free_mnt_opts(&opts);
1020
1021         return rc;
1022 }
1023
1024 static inline u16 inode_mode_to_security_class(umode_t mode)
1025 {
1026         switch (mode & S_IFMT) {
1027         case S_IFSOCK:
1028                 return SECCLASS_SOCK_FILE;
1029         case S_IFLNK:
1030                 return SECCLASS_LNK_FILE;
1031         case S_IFREG:
1032                 return SECCLASS_FILE;
1033         case S_IFBLK:
1034                 return SECCLASS_BLK_FILE;
1035         case S_IFDIR:
1036                 return SECCLASS_DIR;
1037         case S_IFCHR:
1038                 return SECCLASS_CHR_FILE;
1039         case S_IFIFO:
1040                 return SECCLASS_FIFO_FILE;
1041
1042         }
1043
1044         return SECCLASS_FILE;
1045 }
1046
1047 static inline int default_protocol_stream(int protocol)
1048 {
1049         return (protocol == IPPROTO_IP || protocol == IPPROTO_TCP);
1050 }
1051
1052 static inline int default_protocol_dgram(int protocol)
1053 {
1054         return (protocol == IPPROTO_IP || protocol == IPPROTO_UDP);
1055 }
1056
1057 static inline u16 socket_type_to_security_class(int family, int type, int protocol)
1058 {
1059         switch (family) {
1060         case PF_UNIX:
1061                 switch (type) {
1062                 case SOCK_STREAM:
1063                 case SOCK_SEQPACKET:
1064                         return SECCLASS_UNIX_STREAM_SOCKET;
1065                 case SOCK_DGRAM:
1066                         return SECCLASS_UNIX_DGRAM_SOCKET;
1067                 }
1068                 break;
1069         case PF_INET:
1070         case PF_INET6:
1071                 switch (type) {
1072                 case SOCK_STREAM:
1073                         if (default_protocol_stream(protocol))
1074                                 return SECCLASS_TCP_SOCKET;
1075                         else
1076                                 return SECCLASS_RAWIP_SOCKET;
1077                 case SOCK_DGRAM:
1078                         if (default_protocol_dgram(protocol))
1079                                 return SECCLASS_UDP_SOCKET;
1080                         else
1081                                 return SECCLASS_RAWIP_SOCKET;
1082                 case SOCK_DCCP:
1083                         return SECCLASS_DCCP_SOCKET;
1084                 default:
1085                         return SECCLASS_RAWIP_SOCKET;
1086                 }
1087                 break;
1088         case PF_NETLINK:
1089                 switch (protocol) {
1090                 case NETLINK_ROUTE:
1091                         return SECCLASS_NETLINK_ROUTE_SOCKET;
1092                 case NETLINK_FIREWALL:
1093                         return SECCLASS_NETLINK_FIREWALL_SOCKET;
1094                 case NETLINK_SOCK_DIAG:
1095                         return SECCLASS_NETLINK_TCPDIAG_SOCKET;
1096                 case NETLINK_NFLOG:
1097                         return SECCLASS_NETLINK_NFLOG_SOCKET;
1098                 case NETLINK_XFRM:
1099                         return SECCLASS_NETLINK_XFRM_SOCKET;
1100                 case NETLINK_SELINUX:
1101                         return SECCLASS_NETLINK_SELINUX_SOCKET;
1102                 case NETLINK_AUDIT:
1103                         return SECCLASS_NETLINK_AUDIT_SOCKET;
1104                 case NETLINK_IP6_FW:
1105                         return SECCLASS_NETLINK_IP6FW_SOCKET;
1106                 case NETLINK_DNRTMSG:
1107                         return SECCLASS_NETLINK_DNRT_SOCKET;
1108                 case NETLINK_KOBJECT_UEVENT:
1109                         return SECCLASS_NETLINK_KOBJECT_UEVENT_SOCKET;
1110                 default:
1111                         return SECCLASS_NETLINK_SOCKET;
1112                 }
1113         case PF_PACKET:
1114                 return SECCLASS_PACKET_SOCKET;
1115         case PF_KEY:
1116                 return SECCLASS_KEY_SOCKET;
1117         case PF_APPLETALK:
1118                 return SECCLASS_APPLETALK_SOCKET;
1119         }
1120
1121         return SECCLASS_SOCKET;
1122 }
1123
1124 #ifdef CONFIG_PROC_FS
1125 static int selinux_proc_get_sid(struct dentry *dentry,
1126                                 u16 tclass,
1127                                 u32 *sid)
1128 {
1129         int rc;
1130         char *buffer, *path;
1131
1132         buffer = (char *)__get_free_page(GFP_KERNEL);
1133         if (!buffer)
1134                 return -ENOMEM;
1135
1136         path = dentry_path_raw(dentry, buffer, PAGE_SIZE);
1137         if (IS_ERR(path))
1138                 rc = PTR_ERR(path);
1139         else {
1140                 /* each process gets a /proc/PID/ entry. Strip off the
1141                  * PID part to get a valid selinux labeling.
1142                  * e.g. /proc/1/net/rpc/nfs -> /net/rpc/nfs */
1143                 while (path[1] >= '0' && path[1] <= '9') {
1144                         path[1] = '/';
1145                         path++;
1146                 }
1147                 rc = security_genfs_sid("proc", path, tclass, sid);
1148         }
1149         free_page((unsigned long)buffer);
1150         return rc;
1151 }
1152 #else
1153 static int selinux_proc_get_sid(struct dentry *dentry,
1154                                 u16 tclass,
1155                                 u32 *sid)
1156 {
1157         return -EINVAL;
1158 }
1159 #endif
1160
1161 /* The inode's security attributes must be initialized before first use. */
1162 static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dentry)
1163 {
1164         struct superblock_security_struct *sbsec = NULL;
1165         struct inode_security_struct *isec = inode->i_security;
1166         u32 sid;
1167         struct dentry *dentry;
1168 #define INITCONTEXTLEN 255
1169         char *context = NULL;
1170         unsigned len = 0;
1171         int rc = 0;
1172
1173         if (isec->initialized)
1174                 goto out;
1175
1176         mutex_lock(&isec->lock);
1177         if (isec->initialized)
1178                 goto out_unlock;
1179
1180         sbsec = inode->i_sb->s_security;
1181         if (!(sbsec->flags & SE_SBINITIALIZED)) {
1182                 /* Defer initialization until selinux_complete_init,
1183                    after the initial policy is loaded and the security
1184                    server is ready to handle calls. */
1185                 spin_lock(&sbsec->isec_lock);
1186                 if (list_empty(&isec->list))
1187                         list_add(&isec->list, &sbsec->isec_head);
1188                 spin_unlock(&sbsec->isec_lock);
1189                 goto out_unlock;
1190         }
1191
1192         switch (sbsec->behavior) {
1193         case SECURITY_FS_USE_XATTR:
1194                 if (!inode->i_op->getxattr) {
1195                         isec->sid = sbsec->def_sid;
1196                         break;
1197                 }
1198
1199                 /* Need a dentry, since the xattr API requires one.
1200                    Life would be simpler if we could just pass the inode. */
1201                 if (opt_dentry) {
1202                         /* Called from d_instantiate or d_splice_alias. */
1203                         dentry = dget(opt_dentry);
1204                 } else {
1205                         /* Called from selinux_complete_init, try to find a dentry. */
1206                         dentry = d_find_alias(inode);
1207                 }
1208                 if (!dentry) {
1209                         /*
1210                          * this is can be hit on boot when a file is accessed
1211                          * before the policy is loaded.  When we load policy we
1212                          * may find inodes that have no dentry on the
1213                          * sbsec->isec_head list.  No reason to complain as these
1214                          * will get fixed up the next time we go through
1215                          * inode_doinit with a dentry, before these inodes could
1216                          * be used again by userspace.
1217                          */
1218                         goto out_unlock;
1219                 }
1220
1221                 len = INITCONTEXTLEN;
1222                 context = kmalloc(len+1, GFP_NOFS);
1223                 if (!context) {
1224                         rc = -ENOMEM;
1225                         dput(dentry);
1226                         goto out_unlock;
1227                 }
1228                 context[len] = '\0';
1229                 rc = inode->i_op->getxattr(dentry, XATTR_NAME_SELINUX,
1230                                            context, len);
1231                 if (rc == -ERANGE) {
1232                         kfree(context);
1233
1234                         /* Need a larger buffer.  Query for the right size. */
1235                         rc = inode->i_op->getxattr(dentry, XATTR_NAME_SELINUX,
1236                                                    NULL, 0);
1237                         if (rc < 0) {
1238                                 dput(dentry);
1239                                 goto out_unlock;
1240                         }
1241                         len = rc;
1242                         context = kmalloc(len+1, GFP_NOFS);
1243                         if (!context) {
1244                                 rc = -ENOMEM;
1245                                 dput(dentry);
1246                                 goto out_unlock;
1247                         }
1248                         context[len] = '\0';
1249                         rc = inode->i_op->getxattr(dentry,
1250                                                    XATTR_NAME_SELINUX,
1251                                                    context, len);
1252                 }
1253                 dput(dentry);
1254                 if (rc < 0) {
1255                         if (rc != -ENODATA) {
1256                                 printk(KERN_WARNING "SELinux: %s:  getxattr returned "
1257                                        "%d for dev=%s ino=%ld\n", __func__,
1258                                        -rc, inode->i_sb->s_id, inode->i_ino);
1259                                 kfree(context);
1260                                 goto out_unlock;
1261                         }
1262                         /* Map ENODATA to the default file SID */
1263                         sid = sbsec->def_sid;
1264                         rc = 0;
1265                 } else {
1266                         rc = security_context_to_sid_default(context, rc, &sid,
1267                                                              sbsec->def_sid,
1268                                                              GFP_NOFS);
1269                         if (rc) {
1270                                 char *dev = inode->i_sb->s_id;
1271                                 unsigned long ino = inode->i_ino;
1272
1273                                 if (rc == -EINVAL) {
1274                                         if (printk_ratelimit())
1275                                                 printk(KERN_NOTICE "SELinux: inode=%lu on dev=%s was found to have an invalid "
1276                                                         "context=%s.  This indicates you may need to relabel the inode or the "
1277                                                         "filesystem in question.\n", ino, dev, context);
1278                                 } else {
1279                                         printk(KERN_WARNING "SELinux: %s:  context_to_sid(%s) "
1280                                                "returned %d for dev=%s ino=%ld\n",
1281                                                __func__, context, -rc, dev, ino);
1282                                 }
1283                                 kfree(context);
1284                                 /* Leave with the unlabeled SID */
1285                                 rc = 0;
1286                                 break;
1287                         }
1288                 }
1289                 kfree(context);
1290                 isec->sid = sid;
1291                 break;
1292         case SECURITY_FS_USE_TASK:
1293                 isec->sid = isec->task_sid;
1294                 break;
1295         case SECURITY_FS_USE_TRANS:
1296                 /* Default to the fs SID. */
1297                 isec->sid = sbsec->sid;
1298
1299                 /* Try to obtain a transition SID. */
1300                 isec->sclass = inode_mode_to_security_class(inode->i_mode);
1301                 rc = security_transition_sid(isec->task_sid, sbsec->sid,
1302                                              isec->sclass, NULL, &sid);
1303                 if (rc)
1304                         goto out_unlock;
1305                 isec->sid = sid;
1306                 break;
1307         case SECURITY_FS_USE_MNTPOINT:
1308                 isec->sid = sbsec->mntpoint_sid;
1309                 break;
1310         default:
1311                 /* Default to the fs superblock SID. */
1312                 isec->sid = sbsec->sid;
1313
1314                 if ((sbsec->flags & SE_SBPROC) && !S_ISLNK(inode->i_mode)) {
1315                         if (opt_dentry) {
1316                                 isec->sclass = inode_mode_to_security_class(inode->i_mode);
1317                                 rc = selinux_proc_get_sid(opt_dentry,
1318                                                           isec->sclass,
1319                                                           &sid);
1320                                 if (rc)
1321                                         goto out_unlock;
1322                                 isec->sid = sid;
1323                         }
1324                 }
1325                 break;
1326         }
1327
1328         isec->initialized = 1;
1329
1330 out_unlock:
1331         mutex_unlock(&isec->lock);
1332 out:
1333         if (isec->sclass == SECCLASS_FILE)
1334                 isec->sclass = inode_mode_to_security_class(inode->i_mode);
1335         return rc;
1336 }
1337
1338 /* Convert a Linux signal to an access vector. */
1339 static inline u32 signal_to_av(int sig)
1340 {
1341         u32 perm = 0;
1342
1343         switch (sig) {
1344         case SIGCHLD:
1345                 /* Commonly granted from child to parent. */
1346                 perm = PROCESS__SIGCHLD;
1347                 break;
1348         case SIGKILL:
1349                 /* Cannot be caught or ignored */
1350                 perm = PROCESS__SIGKILL;
1351                 break;
1352         case SIGSTOP:
1353                 /* Cannot be caught or ignored */
1354                 perm = PROCESS__SIGSTOP;
1355                 break;
1356         default:
1357                 /* All other signals. */
1358                 perm = PROCESS__SIGNAL;
1359                 break;
1360         }
1361
1362         return perm;
1363 }
1364
1365 /*
1366  * Check permission between a pair of credentials
1367  * fork check, ptrace check, etc.
1368  */
1369 static int cred_has_perm(const struct cred *actor,
1370                          const struct cred *target,
1371                          u32 perms)
1372 {
1373         u32 asid = cred_sid(actor), tsid = cred_sid(target);
1374
1375         return avc_has_perm(asid, tsid, SECCLASS_PROCESS, perms, NULL);
1376 }
1377
1378 /*
1379  * Check permission between a pair of tasks, e.g. signal checks,
1380  * fork check, ptrace check, etc.
1381  * tsk1 is the actor and tsk2 is the target
1382  * - this uses the default subjective creds of tsk1
1383  */
1384 static int task_has_perm(const struct task_struct *tsk1,
1385                          const struct task_struct *tsk2,
1386                          u32 perms)
1387 {
1388         const struct task_security_struct *__tsec1, *__tsec2;
1389         u32 sid1, sid2;
1390
1391         rcu_read_lock();
1392         __tsec1 = __task_cred(tsk1)->security;  sid1 = __tsec1->sid;
1393         __tsec2 = __task_cred(tsk2)->security;  sid2 = __tsec2->sid;
1394         rcu_read_unlock();
1395         return avc_has_perm(sid1, sid2, SECCLASS_PROCESS, perms, NULL);
1396 }
1397
1398 /*
1399  * Check permission between current and another task, e.g. signal checks,
1400  * fork check, ptrace check, etc.
1401  * current is the actor and tsk2 is the target
1402  * - this uses current's subjective creds
1403  */
1404 static int current_has_perm(const struct task_struct *tsk,
1405                             u32 perms)
1406 {
1407         u32 sid, tsid;
1408
1409         sid = current_sid();
1410         tsid = task_sid(tsk);
1411         return avc_has_perm(sid, tsid, SECCLASS_PROCESS, perms, NULL);
1412 }
1413
1414 #if CAP_LAST_CAP > 63
1415 #error Fix SELinux to handle capabilities > 63.
1416 #endif
1417
1418 /* Check whether a task is allowed to use a capability. */
1419 static int cred_has_capability(const struct cred *cred,
1420                                int cap, int audit)
1421 {
1422         struct common_audit_data ad;
1423         struct av_decision avd;
1424         u16 sclass;
1425         u32 sid = cred_sid(cred);
1426         u32 av = CAP_TO_MASK(cap);
1427         int rc;
1428
1429         ad.type = LSM_AUDIT_DATA_CAP;
1430         ad.u.cap = cap;
1431
1432         switch (CAP_TO_INDEX(cap)) {
1433         case 0:
1434                 sclass = SECCLASS_CAPABILITY;
1435                 break;
1436         case 1:
1437                 sclass = SECCLASS_CAPABILITY2;
1438                 break;
1439         default:
1440                 printk(KERN_ERR
1441                        "SELinux:  out of range capability %d\n", cap);
1442                 BUG();
1443                 return -EINVAL;
1444         }
1445
1446         rc = avc_has_perm_noaudit(sid, sid, sclass, av, 0, &avd);
1447         if (audit == SECURITY_CAP_AUDIT) {
1448                 int rc2 = avc_audit(sid, sid, sclass, av, &avd, rc, &ad, 0);
1449                 if (rc2)
1450                         return rc2;
1451         }
1452         return rc;
1453 }
1454
1455 /* Check whether a task is allowed to use a system operation. */
1456 static int task_has_system(struct task_struct *tsk,
1457                            u32 perms)
1458 {
1459         u32 sid = task_sid(tsk);
1460
1461         return avc_has_perm(sid, SECINITSID_KERNEL,
1462                             SECCLASS_SYSTEM, perms, NULL);
1463 }
1464
1465 /* Check whether a task has a particular permission to an inode.
1466    The 'adp' parameter is optional and allows other audit
1467    data to be passed (e.g. the dentry). */
1468 static int inode_has_perm(const struct cred *cred,
1469                           struct inode *inode,
1470                           u32 perms,
1471                           struct common_audit_data *adp,
1472                           unsigned flags)
1473 {
1474         struct inode_security_struct *isec;
1475         u32 sid;
1476
1477         validate_creds(cred);
1478
1479         if (unlikely(IS_PRIVATE(inode)))
1480                 return 0;
1481
1482         sid = cred_sid(cred);
1483         isec = inode->i_security;
1484
1485         return avc_has_perm_flags(sid, isec->sid, isec->sclass, perms, adp, flags);
1486 }
1487
1488 /* Same as inode_has_perm, but pass explicit audit data containing
1489    the dentry to help the auditing code to more easily generate the
1490    pathname if needed. */
1491 static inline int dentry_has_perm(const struct cred *cred,
1492                                   struct dentry *dentry,
1493                                   u32 av)
1494 {
1495         struct inode *inode = dentry->d_inode;
1496         struct common_audit_data ad;
1497
1498         ad.type = LSM_AUDIT_DATA_DENTRY;
1499         ad.u.dentry = dentry;
1500         return inode_has_perm(cred, inode, av, &ad, 0);
1501 }
1502
1503 /* Same as inode_has_perm, but pass explicit audit data containing
1504    the path to help the auditing code to more easily generate the
1505    pathname if needed. */
1506 static inline int path_has_perm(const struct cred *cred,
1507                                 struct path *path,
1508                                 u32 av)
1509 {
1510         struct inode *inode = path->dentry->d_inode;
1511         struct common_audit_data ad;
1512
1513         ad.type = LSM_AUDIT_DATA_PATH;
1514         ad.u.path = *path;
1515         return inode_has_perm(cred, inode, av, &ad, 0);
1516 }
1517
1518 /* Check whether a task can use an open file descriptor to
1519    access an inode in a given way.  Check access to the
1520    descriptor itself, and then use dentry_has_perm to
1521    check a particular permission to the file.
1522    Access to the descriptor is implicitly granted if it
1523    has the same SID as the process.  If av is zero, then
1524    access to the file is not checked, e.g. for cases
1525    where only the descriptor is affected like seek. */
1526 static int file_has_perm(const struct cred *cred,
1527                          struct file *file,
1528                          u32 av)
1529 {
1530         struct file_security_struct *fsec = file->f_security;
1531         struct inode *inode = file->f_path.dentry->d_inode;
1532         struct common_audit_data ad;
1533         u32 sid = cred_sid(cred);
1534         int rc;
1535
1536         ad.type = LSM_AUDIT_DATA_PATH;
1537         ad.u.path = file->f_path;
1538
1539         if (sid != fsec->sid) {
1540                 rc = avc_has_perm(sid, fsec->sid,
1541                                   SECCLASS_FD,
1542                                   FD__USE,
1543                                   &ad);
1544                 if (rc)
1545                         goto out;
1546         }
1547
1548         /* av is zero if only checking access to the descriptor. */
1549         rc = 0;
1550         if (av)
1551                 rc = inode_has_perm(cred, inode, av, &ad, 0);
1552
1553 out:
1554         return rc;
1555 }
1556
1557 /* Check whether a task can create a file. */
1558 static int may_create(struct inode *dir,
1559                       struct dentry *dentry,
1560                       u16 tclass)
1561 {
1562         const struct task_security_struct *tsec = current_security();
1563         struct inode_security_struct *dsec;
1564         struct superblock_security_struct *sbsec;
1565         u32 sid, newsid;
1566         struct common_audit_data ad;
1567         int rc;
1568
1569         dsec = dir->i_security;
1570         sbsec = dir->i_sb->s_security;
1571
1572         sid = tsec->sid;
1573         newsid = tsec->create_sid;
1574
1575         ad.type = LSM_AUDIT_DATA_DENTRY;
1576         ad.u.dentry = dentry;
1577
1578         rc = avc_has_perm(sid, dsec->sid, SECCLASS_DIR,
1579                           DIR__ADD_NAME | DIR__SEARCH,
1580                           &ad);
1581         if (rc)
1582                 return rc;
1583
1584         if (!newsid || !(sbsec->flags & SE_SBLABELSUPP)) {
1585                 rc = security_transition_sid(sid, dsec->sid, tclass,
1586                                              &dentry->d_name, &newsid);
1587                 if (rc)
1588                         return rc;
1589         }
1590
1591         rc = avc_has_perm(sid, newsid, tclass, FILE__CREATE, &ad);
1592         if (rc)
1593                 return rc;
1594
1595         return avc_has_perm(newsid, sbsec->sid,
1596                             SECCLASS_FILESYSTEM,
1597                             FILESYSTEM__ASSOCIATE, &ad);
1598 }
1599
1600 /* Check whether a task can create a key. */
1601 static int may_create_key(u32 ksid,
1602                           struct task_struct *ctx)
1603 {
1604         u32 sid = task_sid(ctx);
1605
1606         return avc_has_perm(sid, ksid, SECCLASS_KEY, KEY__CREATE, NULL);
1607 }
1608
1609 #define MAY_LINK        0
1610 #define MAY_UNLINK      1
1611 #define MAY_RMDIR       2
1612
1613 /* Check whether a task can link, unlink, or rmdir a file/directory. */
1614 static int may_link(struct inode *dir,
1615                     struct dentry *dentry,
1616                     int kind)
1617
1618 {
1619         struct inode_security_struct *dsec, *isec;
1620         struct common_audit_data ad;
1621         u32 sid = current_sid();
1622         u32 av;
1623         int rc;
1624
1625         dsec = dir->i_security;
1626         isec = dentry->d_inode->i_security;
1627
1628         ad.type = LSM_AUDIT_DATA_DENTRY;
1629         ad.u.dentry = dentry;
1630
1631         av = DIR__SEARCH;
1632         av |= (kind ? DIR__REMOVE_NAME : DIR__ADD_NAME);
1633         rc = avc_has_perm(sid, dsec->sid, SECCLASS_DIR, av, &ad);
1634         if (rc)
1635                 return rc;
1636
1637         switch (kind) {
1638         case MAY_LINK:
1639                 av = FILE__LINK;
1640                 break;
1641         case MAY_UNLINK:
1642                 av = FILE__UNLINK;
1643                 break;
1644         case MAY_RMDIR:
1645                 av = DIR__RMDIR;
1646                 break;
1647         default:
1648                 printk(KERN_WARNING "SELinux: %s:  unrecognized kind %d\n",
1649                         __func__, kind);
1650                 return 0;
1651         }
1652
1653         rc = avc_has_perm(sid, isec->sid, isec->sclass, av, &ad);
1654         return rc;
1655 }
1656
1657 static inline int may_rename(struct inode *old_dir,
1658                              struct dentry *old_dentry,
1659                              struct inode *new_dir,
1660                              struct dentry *new_dentry)
1661 {
1662         struct inode_security_struct *old_dsec, *new_dsec, *old_isec, *new_isec;
1663         struct common_audit_data ad;
1664         u32 sid = current_sid();
1665         u32 av;
1666         int old_is_dir, new_is_dir;
1667         int rc;
1668
1669         old_dsec = old_dir->i_security;
1670         old_isec = old_dentry->d_inode->i_security;
1671         old_is_dir = S_ISDIR(old_dentry->d_inode->i_mode);
1672         new_dsec = new_dir->i_security;
1673
1674         ad.type = LSM_AUDIT_DATA_DENTRY;
1675
1676         ad.u.dentry = old_dentry;
1677         rc = avc_has_perm(sid, old_dsec->sid, SECCLASS_DIR,
1678                           DIR__REMOVE_NAME | DIR__SEARCH, &ad);
1679         if (rc)
1680                 return rc;
1681         rc = avc_has_perm(sid, old_isec->sid,
1682                           old_isec->sclass, FILE__RENAME, &ad);
1683         if (rc)
1684                 return rc;
1685         if (old_is_dir && new_dir != old_dir) {
1686                 rc = avc_has_perm(sid, old_isec->sid,
1687                                   old_isec->sclass, DIR__REPARENT, &ad);
1688                 if (rc)
1689                         return rc;
1690         }
1691
1692         ad.u.dentry = new_dentry;
1693         av = DIR__ADD_NAME | DIR__SEARCH;
1694         if (new_dentry->d_inode)
1695                 av |= DIR__REMOVE_NAME;
1696         rc = avc_has_perm(sid, new_dsec->sid, SECCLASS_DIR, av, &ad);
1697         if (rc)
1698                 return rc;
1699         if (new_dentry->d_inode) {
1700                 new_isec = new_dentry->d_inode->i_security;
1701                 new_is_dir = S_ISDIR(new_dentry->d_inode->i_mode);
1702                 rc = avc_has_perm(sid, new_isec->sid,
1703                                   new_isec->sclass,
1704                                   (new_is_dir ? DIR__RMDIR : FILE__UNLINK), &ad);
1705                 if (rc)
1706                         return rc;
1707         }
1708
1709         return 0;
1710 }
1711
1712 /* Check whether a task can perform a filesystem operation. */
1713 static int superblock_has_perm(const struct cred *cred,
1714                                struct super_block *sb,
1715                                u32 perms,
1716                                struct common_audit_data *ad)
1717 {
1718         struct superblock_security_struct *sbsec;
1719         u32 sid = cred_sid(cred);
1720
1721         sbsec = sb->s_security;
1722         return avc_has_perm(sid, sbsec->sid, SECCLASS_FILESYSTEM, perms, ad);
1723 }
1724
1725 /* Convert a Linux mode and permission mask to an access vector. */
1726 static inline u32 file_mask_to_av(int mode, int mask)
1727 {
1728         u32 av = 0;
1729
1730         if (!S_ISDIR(mode)) {
1731                 if (mask & MAY_EXEC)
1732                         av |= FILE__EXECUTE;
1733                 if (mask & MAY_READ)
1734                         av |= FILE__READ;
1735
1736                 if (mask & MAY_APPEND)
1737                         av |= FILE__APPEND;
1738                 else if (mask & MAY_WRITE)
1739                         av |= FILE__WRITE;
1740
1741         } else {
1742                 if (mask & MAY_EXEC)
1743                         av |= DIR__SEARCH;
1744                 if (mask & MAY_WRITE)
1745                         av |= DIR__WRITE;
1746                 if (mask & MAY_READ)
1747                         av |= DIR__READ;
1748         }
1749
1750         return av;
1751 }
1752
1753 /* Convert a Linux file to an access vector. */
1754 static inline u32 file_to_av(struct file *file)
1755 {
1756         u32 av = 0;
1757
1758         if (file->f_mode & FMODE_READ)
1759                 av |= FILE__READ;
1760         if (file->f_mode & FMODE_WRITE) {
1761                 if (file->f_flags & O_APPEND)
1762                         av |= FILE__APPEND;
1763                 else
1764                         av |= FILE__WRITE;
1765         }
1766         if (!av) {
1767                 /*
1768                  * Special file opened with flags 3 for ioctl-only use.
1769                  */
1770                 av = FILE__IOCTL;
1771         }
1772
1773         return av;
1774 }
1775
1776 /*
1777  * Convert a file to an access vector and include the correct open
1778  * open permission.
1779  */
1780 static inline u32 open_file_to_av(struct file *file)
1781 {
1782         u32 av = file_to_av(file);
1783
1784         if (selinux_policycap_openperm)
1785                 av |= FILE__OPEN;
1786
1787         return av;
1788 }
1789
1790 /* Hook functions begin here. */
1791
1792 static int selinux_ptrace_access_check(struct task_struct *child,
1793                                      unsigned int mode)
1794 {
1795         int rc;
1796
1797         rc = cap_ptrace_access_check(child, mode);
1798         if (rc)
1799                 return rc;
1800
1801         if (mode & PTRACE_MODE_READ) {
1802                 u32 sid = current_sid();
1803                 u32 csid = task_sid(child);
1804                 return avc_has_perm(sid, csid, SECCLASS_FILE, FILE__READ, NULL);
1805         }
1806
1807         return current_has_perm(child, PROCESS__PTRACE);
1808 }
1809
1810 static int selinux_ptrace_traceme(struct task_struct *parent)
1811 {
1812         int rc;
1813
1814         rc = cap_ptrace_traceme(parent);
1815         if (rc)
1816                 return rc;
1817
1818         return task_has_perm(parent, current, PROCESS__PTRACE);
1819 }
1820
1821 static int selinux_capget(struct task_struct *target, kernel_cap_t *effective,
1822                           kernel_cap_t *inheritable, kernel_cap_t *permitted)
1823 {
1824         int error;
1825
1826         error = current_has_perm(target, PROCESS__GETCAP);
1827         if (error)
1828                 return error;
1829
1830         return cap_capget(target, effective, inheritable, permitted);
1831 }
1832
1833 static int selinux_capset(struct cred *new, const struct cred *old,
1834                           const kernel_cap_t *effective,
1835                           const kernel_cap_t *inheritable,
1836                           const kernel_cap_t *permitted)
1837 {
1838         int error;
1839
1840         error = cap_capset(new, old,
1841                                       effective, inheritable, permitted);
1842         if (error)
1843                 return error;
1844
1845         return cred_has_perm(old, new, PROCESS__SETCAP);
1846 }
1847
1848 /*
1849  * (This comment used to live with the selinux_task_setuid hook,
1850  * which was removed).
1851  *
1852  * Since setuid only affects the current process, and since the SELinux
1853  * controls are not based on the Linux identity attributes, SELinux does not
1854  * need to control this operation.  However, SELinux does control the use of
1855  * the CAP_SETUID and CAP_SETGID capabilities using the capable hook.
1856  */
1857
1858 static int selinux_capable(const struct cred *cred, struct user_namespace *ns,
1859                            int cap, int audit)
1860 {
1861         int rc;
1862
1863         rc = cap_capable(cred, ns, cap, audit);
1864         if (rc)
1865                 return rc;
1866
1867         return cred_has_capability(cred, cap, audit);
1868 }
1869
1870 static int selinux_quotactl(int cmds, int type, int id, struct super_block *sb)
1871 {
1872         const struct cred *cred = current_cred();
1873         int rc = 0;
1874
1875         if (!sb)
1876                 return 0;
1877
1878         switch (cmds) {
1879         case Q_SYNC:
1880         case Q_QUOTAON:
1881         case Q_QUOTAOFF:
1882         case Q_SETINFO:
1883         case Q_SETQUOTA:
1884                 rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAMOD, NULL);
1885                 break;
1886         case Q_GETFMT:
1887         case Q_GETINFO:
1888         case Q_GETQUOTA:
1889                 rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAGET, NULL);
1890                 break;
1891         default:
1892                 rc = 0;  /* let the kernel handle invalid cmds */
1893                 break;
1894         }
1895         return rc;
1896 }
1897
1898 static int selinux_quota_on(struct dentry *dentry)
1899 {
1900         const struct cred *cred = current_cred();
1901
1902         return dentry_has_perm(cred, dentry, FILE__QUOTAON);
1903 }
1904
1905 static int selinux_syslog(int type)
1906 {
1907         int rc;
1908
1909         switch (type) {
1910         case SYSLOG_ACTION_READ_ALL:    /* Read last kernel messages */
1911         case SYSLOG_ACTION_SIZE_BUFFER: /* Return size of the log buffer */
1912                 rc = task_has_system(current, SYSTEM__SYSLOG_READ);
1913                 break;
1914         case SYSLOG_ACTION_CONSOLE_OFF: /* Disable logging to console */
1915         case SYSLOG_ACTION_CONSOLE_ON:  /* Enable logging to console */
1916         /* Set level of messages printed to console */
1917         case SYSLOG_ACTION_CONSOLE_LEVEL:
1918                 rc = task_has_system(current, SYSTEM__SYSLOG_CONSOLE);
1919                 break;
1920         case SYSLOG_ACTION_CLOSE:       /* Close log */
1921         case SYSLOG_ACTION_OPEN:        /* Open log */
1922         case SYSLOG_ACTION_READ:        /* Read from log */
1923         case SYSLOG_ACTION_READ_CLEAR:  /* Read/clear last kernel messages */
1924         case SYSLOG_ACTION_CLEAR:       /* Clear ring buffer */
1925         default:
1926                 rc = task_has_system(current, SYSTEM__SYSLOG_MOD);
1927                 break;
1928         }
1929         return rc;
1930 }
1931
1932 /*
1933  * Check that a process has enough memory to allocate a new virtual
1934  * mapping. 0 means there is enough memory for the allocation to
1935  * succeed and -ENOMEM implies there is not.
1936  *
1937  * Do not audit the selinux permission check, as this is applied to all
1938  * processes that allocate mappings.
1939  */
1940 static int selinux_vm_enough_memory(struct mm_struct *mm, long pages)
1941 {
1942         int rc, cap_sys_admin = 0;
1943
1944         rc = selinux_capable(current_cred(), &init_user_ns, CAP_SYS_ADMIN,
1945                              SECURITY_CAP_NOAUDIT);
1946         if (rc == 0)
1947                 cap_sys_admin = 1;
1948
1949         return __vm_enough_memory(mm, pages, cap_sys_admin);
1950 }
1951
1952 /* binprm security operations */
1953
1954 static int selinux_bprm_set_creds(struct linux_binprm *bprm)
1955 {
1956         const struct task_security_struct *old_tsec;
1957         struct task_security_struct *new_tsec;
1958         struct inode_security_struct *isec;
1959         struct common_audit_data ad;
1960         struct inode *inode = bprm->file->f_path.dentry->d_inode;
1961         int rc;
1962
1963         rc = cap_bprm_set_creds(bprm);
1964         if (rc)
1965                 return rc;
1966
1967         /* SELinux context only depends on initial program or script and not
1968          * the script interpreter */
1969         if (bprm->cred_prepared)
1970                 return 0;
1971
1972         old_tsec = current_security();
1973         new_tsec = bprm->cred->security;
1974         isec = inode->i_security;
1975
1976         /* Default to the current task SID. */
1977         new_tsec->sid = old_tsec->sid;
1978         new_tsec->osid = old_tsec->sid;
1979
1980         /* Reset fs, key, and sock SIDs on execve. */
1981         new_tsec->create_sid = 0;
1982         new_tsec->keycreate_sid = 0;
1983         new_tsec->sockcreate_sid = 0;
1984
1985         if (old_tsec->exec_sid) {
1986                 new_tsec->sid = old_tsec->exec_sid;
1987                 /* Reset exec SID on execve. */
1988                 new_tsec->exec_sid = 0;
1989
1990                 /*
1991                  * Minimize confusion: if no_new_privs and a transition is
1992                  * explicitly requested, then fail the exec.
1993                  */
1994                 if (bprm->unsafe & LSM_UNSAFE_NO_NEW_PRIVS)
1995                         return -EPERM;
1996         } else {
1997                 /* Check for a default transition on this program. */
1998                 rc = security_transition_sid(old_tsec->sid, isec->sid,
1999                                              SECCLASS_PROCESS, NULL,
2000                                              &new_tsec->sid);
2001                 if (rc)
2002                         return rc;
2003         }
2004
2005         ad.type = LSM_AUDIT_DATA_PATH;
2006         ad.u.path = bprm->file->f_path;
2007
2008         if ((bprm->file->f_path.mnt->mnt_flags & MNT_NOSUID) ||
2009             (bprm->unsafe & LSM_UNSAFE_NO_NEW_PRIVS))
2010                 new_tsec->sid = old_tsec->sid;
2011
2012         if (new_tsec->sid == old_tsec->sid) {
2013                 rc = avc_has_perm(old_tsec->sid, isec->sid,
2014                                   SECCLASS_FILE, FILE__EXECUTE_NO_TRANS, &ad);
2015                 if (rc)
2016                         return rc;
2017         } else {
2018                 /* Check permissions for the transition. */
2019                 rc = avc_has_perm(old_tsec->sid, new_tsec->sid,
2020                                   SECCLASS_PROCESS, PROCESS__TRANSITION, &ad);
2021                 if (rc)
2022                         return rc;
2023
2024                 rc = avc_has_perm(new_tsec->sid, isec->sid,
2025                                   SECCLASS_FILE, FILE__ENTRYPOINT, &ad);
2026                 if (rc)
2027                         return rc;
2028
2029                 /* Check for shared state */
2030                 if (bprm->unsafe & LSM_UNSAFE_SHARE) {
2031                         rc = avc_has_perm(old_tsec->sid, new_tsec->sid,
2032                                           SECCLASS_PROCESS, PROCESS__SHARE,
2033                                           NULL);
2034                         if (rc)
2035                                 return -EPERM;
2036                 }
2037
2038                 /* Make sure that anyone attempting to ptrace over a task that
2039                  * changes its SID has the appropriate permit */
2040                 if (bprm->unsafe &
2041                     (LSM_UNSAFE_PTRACE | LSM_UNSAFE_PTRACE_CAP)) {
2042                         struct task_struct *tracer;
2043                         struct task_security_struct *sec;
2044                         u32 ptsid = 0;
2045
2046                         rcu_read_lock();
2047                         tracer = ptrace_parent(current);
2048                         if (likely(tracer != NULL)) {
2049                                 sec = __task_cred(tracer)->security;
2050                                 ptsid = sec->sid;
2051                         }
2052                         rcu_read_unlock();
2053
2054                         if (ptsid != 0) {
2055                                 rc = avc_has_perm(ptsid, new_tsec->sid,
2056                                                   SECCLASS_PROCESS,
2057                                                   PROCESS__PTRACE, NULL);
2058                                 if (rc)
2059                                         return -EPERM;
2060                         }
2061                 }
2062
2063                 /* Clear any possibly unsafe personality bits on exec: */
2064                 bprm->per_clear |= PER_CLEAR_ON_SETID;
2065         }
2066
2067         return 0;
2068 }
2069
2070 static int selinux_bprm_secureexec(struct linux_binprm *bprm)
2071 {
2072         const struct task_security_struct *tsec = current_security();
2073         u32 sid, osid;
2074         int atsecure = 0;
2075
2076         sid = tsec->sid;
2077         osid = tsec->osid;
2078
2079         if (osid != sid) {
2080                 /* Enable secure mode for SIDs transitions unless
2081                    the noatsecure permission is granted between
2082                    the two SIDs, i.e. ahp returns 0. */
2083                 atsecure = avc_has_perm(osid, sid,
2084                                         SECCLASS_PROCESS,
2085                                         PROCESS__NOATSECURE, NULL);
2086         }
2087
2088         return (atsecure || cap_bprm_secureexec(bprm));
2089 }
2090
2091 /* Derived from fs/exec.c:flush_old_files. */
2092 static inline void flush_unauthorized_files(const struct cred *cred,
2093                                             struct files_struct *files)
2094 {
2095         struct file *file, *devnull = NULL;
2096         struct tty_struct *tty;
2097         struct fdtable *fdt;
2098         long j = -1;
2099         int drop_tty = 0;
2100
2101         tty = get_current_tty();
2102         if (tty) {
2103                 spin_lock(&tty_files_lock);
2104                 if (!list_empty(&tty->tty_files)) {
2105                         struct tty_file_private *file_priv;
2106
2107                         /* Revalidate access to controlling tty.
2108                            Use path_has_perm on the tty path directly rather
2109                            than using file_has_perm, as this particular open
2110                            file may belong to another process and we are only
2111                            interested in the inode-based check here. */
2112                         file_priv = list_first_entry(&tty->tty_files,
2113                                                 struct tty_file_private, list);
2114                         file = file_priv->file;
2115                         if (path_has_perm(cred, &file->f_path, FILE__READ | FILE__WRITE))
2116                                 drop_tty = 1;
2117                 }
2118                 spin_unlock(&tty_files_lock);
2119                 tty_kref_put(tty);
2120         }
2121         /* Reset controlling tty. */
2122         if (drop_tty)
2123                 no_tty();
2124
2125         /* Revalidate access to inherited open files. */
2126         spin_lock(&files->file_lock);
2127         for (;;) {
2128                 unsigned long set, i;
2129                 int fd;
2130
2131                 j++;
2132                 i = j * __NFDBITS;
2133                 fdt = files_fdtable(files);
2134                 if (i >= fdt->max_fds)
2135                         break;
2136                 set = fdt->open_fds[j];
2137                 if (!set)
2138                         continue;
2139                 spin_unlock(&files->file_lock);
2140                 for ( ; set ; i++, set >>= 1) {
2141                         if (set & 1) {
2142                                 file = fget(i);
2143                                 if (!file)
2144                                         continue;
2145                                 if (file_has_perm(cred,
2146                                                   file,
2147                                                   file_to_av(file))) {
2148                                         sys_close(i);
2149                                         fd = get_unused_fd();
2150                                         if (fd != i) {
2151                                                 if (fd >= 0)
2152                                                         put_unused_fd(fd);
2153                                                 fput(file);
2154                                                 continue;
2155                                         }
2156                                         if (devnull) {
2157                                                 get_file(devnull);
2158                                         } else {
2159                                                 devnull = dentry_open(
2160                                                         dget(selinux_null),
2161                                                         mntget(selinuxfs_mount),
2162                                                         O_RDWR, cred);
2163                                                 if (IS_ERR(devnull)) {
2164                                                         devnull = NULL;
2165                                                         put_unused_fd(fd);
2166                                                         fput(file);
2167                                                         continue;
2168                                                 }
2169                                         }
2170                                         fd_install(fd, devnull);
2171                                 }
2172                                 fput(file);
2173                         }
2174                 }
2175                 spin_lock(&files->file_lock);
2176
2177         }
2178         spin_unlock(&files->file_lock);
2179 }
2180
2181 /*
2182  * Prepare a process for imminent new credential changes due to exec
2183  */
2184 static void selinux_bprm_committing_creds(struct linux_binprm *bprm)
2185 {
2186         struct task_security_struct *new_tsec;
2187         struct rlimit *rlim, *initrlim;
2188         int rc, i;
2189
2190         new_tsec = bprm->cred->security;
2191         if (new_tsec->sid == new_tsec->osid)
2192                 return;
2193
2194         /* Close files for which the new task SID is not authorized. */
2195         flush_unauthorized_files(bprm->cred, current->files);
2196
2197         /* Always clear parent death signal on SID transitions. */
2198         current->pdeath_signal = 0;
2199
2200         /* Check whether the new SID can inherit resource limits from the old
2201          * SID.  If not, reset all soft limits to the lower of the current
2202          * task's hard limit and the init task's soft limit.
2203          *
2204          * Note that the setting of hard limits (even to lower them) can be
2205          * controlled by the setrlimit check.  The inclusion of the init task's
2206          * soft limit into the computation is to avoid resetting soft limits
2207          * higher than the default soft limit for cases where the default is
2208          * lower than the hard limit, e.g. RLIMIT_CORE or RLIMIT_STACK.
2209          */
2210         rc = avc_has_perm(new_tsec->osid, new_tsec->sid, SECCLASS_PROCESS,
2211                           PROCESS__RLIMITINH, NULL);
2212         if (rc) {
2213                 /* protect against do_prlimit() */
2214                 task_lock(current);
2215                 for (i = 0; i < RLIM_NLIMITS; i++) {
2216                         rlim = current->signal->rlim + i;
2217                         initrlim = init_task.signal->rlim + i;
2218                         rlim->rlim_cur = min(rlim->rlim_max, initrlim->rlim_cur);
2219                 }
2220                 task_unlock(current);
2221                 update_rlimit_cpu(current, rlimit(RLIMIT_CPU));
2222         }
2223 }
2224
2225 /*
2226  * Clean up the process immediately after the installation of new credentials
2227  * due to exec
2228  */
2229 static void selinux_bprm_committed_creds(struct linux_binprm *bprm)
2230 {
2231         const struct task_security_struct *tsec = current_security();
2232         struct itimerval itimer;
2233         u32 osid, sid;
2234         int rc, i;
2235
2236         osid = tsec->osid;
2237         sid = tsec->sid;
2238
2239         if (sid == osid)
2240                 return;
2241
2242         /* Check whether the new SID can inherit signal state from the old SID.
2243          * If not, clear itimers to avoid subsequent signal generation and
2244          * flush and unblock signals.
2245          *
2246          * This must occur _after_ the task SID has been updated so that any
2247          * kill done after the flush will be checked against the new SID.
2248          */
2249         rc = avc_has_perm(osid, sid, SECCLASS_PROCESS, PROCESS__SIGINH, NULL);
2250         if (rc) {
2251                 memset(&itimer, 0, sizeof itimer);
2252                 for (i = 0; i < 3; i++)
2253                         do_setitimer(i, &itimer, NULL);
2254                 spin_lock_irq(&current->sighand->siglock);
2255                 if (!(current->signal->flags & SIGNAL_GROUP_EXIT)) {
2256                         __flush_signals(current);
2257                         flush_signal_handlers(current, 1);
2258                         sigemptyset(&current->blocked);
2259                 }
2260                 spin_unlock_irq(&current->sighand->siglock);
2261         }
2262
2263         /* Wake up the parent if it is waiting so that it can recheck
2264          * wait permission to the new task SID. */
2265         read_lock(&tasklist_lock);
2266         __wake_up_parent(current, current->real_parent);
2267         read_unlock(&tasklist_lock);
2268 }
2269
2270 /* superblock security operations */
2271
2272 static int selinux_sb_alloc_security(struct super_block *sb)
2273 {
2274         return superblock_alloc_security(sb);
2275 }
2276
2277 static void selinux_sb_free_security(struct super_block *sb)
2278 {
2279         superblock_free_security(sb);
2280 }
2281
2282 static inline int match_prefix(char *prefix, int plen, char *option, int olen)
2283 {
2284         if (plen > olen)
2285                 return 0;
2286
2287         return !memcmp(prefix, option, plen);
2288 }
2289
2290 static inline int selinux_option(char *option, int len)
2291 {
2292         return (match_prefix(CONTEXT_STR, sizeof(CONTEXT_STR)-1, option, len) ||
2293                 match_prefix(FSCONTEXT_STR, sizeof(FSCONTEXT_STR)-1, option, len) ||
2294                 match_prefix(DEFCONTEXT_STR, sizeof(DEFCONTEXT_STR)-1, option, len) ||
2295                 match_prefix(ROOTCONTEXT_STR, sizeof(ROOTCONTEXT_STR)-1, option, len) ||
2296                 match_prefix(LABELSUPP_STR, sizeof(LABELSUPP_STR)-1, option, len));
2297 }
2298
2299 static inline void take_option(char **to, char *from, int *first, int len)
2300 {
2301         if (!*first) {
2302                 **to = ',';
2303                 *to += 1;
2304         } else
2305                 *first = 0;
2306         memcpy(*to, from, len);
2307         *to += len;
2308 }
2309
2310 static inline void take_selinux_option(char **to, char *from, int *first,
2311                                        int len)
2312 {
2313         int current_size = 0;
2314
2315         if (!*first) {
2316                 **to = '|';
2317                 *to += 1;
2318         } else
2319                 *first = 0;
2320
2321         while (current_size < len) {
2322                 if (*from != '"') {
2323                         **to = *from;
2324                         *to += 1;
2325                 }
2326                 from += 1;
2327                 current_size += 1;
2328         }
2329 }
2330
2331 static int selinux_sb_copy_data(char *orig, char *copy)
2332 {
2333         int fnosec, fsec, rc = 0;
2334         char *in_save, *in_curr, *in_end;
2335         char *sec_curr, *nosec_save, *nosec;
2336         int open_quote = 0;
2337
2338         in_curr = orig;
2339         sec_curr = copy;
2340
2341         nosec = (char *)get_zeroed_page(GFP_KERNEL);
2342         if (!nosec) {
2343                 rc = -ENOMEM;
2344                 goto out;
2345         }
2346
2347         nosec_save = nosec;
2348         fnosec = fsec = 1;
2349         in_save = in_end = orig;
2350
2351         do {
2352                 if (*in_end == '"')
2353                         open_quote = !open_quote;
2354                 if ((*in_end == ',' && open_quote == 0) ||
2355                                 *in_end == '\0') {
2356                         int len = in_end - in_curr;
2357
2358                         if (selinux_option(in_curr, len))
2359                                 take_selinux_option(&sec_curr, in_curr, &fsec, len);
2360                         else
2361                                 take_option(&nosec, in_curr, &fnosec, len);
2362
2363                         in_curr = in_end + 1;
2364                 }
2365         } while (*in_end++);
2366
2367         strcpy(in_save, nosec_save);
2368         free_page((unsigned long)nosec_save);
2369 out:
2370         return rc;
2371 }
2372
2373 static int selinux_sb_remount(struct super_block *sb, void *data)
2374 {
2375         int rc, i, *flags;
2376         struct security_mnt_opts opts;
2377         char *secdata, **mount_options;
2378         struct superblock_security_struct *sbsec = sb->s_security;
2379
2380         if (!(sbsec->flags & SE_SBINITIALIZED))
2381                 return 0;
2382
2383         if (!data)
2384                 return 0;
2385
2386         if (sb->s_type->fs_flags & FS_BINARY_MOUNTDATA)
2387                 return 0;
2388
2389         security_init_mnt_opts(&opts);
2390         secdata = alloc_secdata();
2391         if (!secdata)
2392                 return -ENOMEM;
2393         rc = selinux_sb_copy_data(data, secdata);
2394         if (rc)
2395                 goto out_free_secdata;
2396
2397         rc = selinux_parse_opts_str(secdata, &opts);
2398         if (rc)
2399                 goto out_free_secdata;
2400
2401         mount_options = opts.mnt_opts;
2402         flags = opts.mnt_opts_flags;
2403
2404         for (i = 0; i < opts.num_mnt_opts; i++) {
2405                 u32 sid;
2406                 size_t len;
2407
2408                 if (flags[i] == SE_SBLABELSUPP)
2409                         continue;
2410                 len = strlen(mount_options[i]);
2411                 rc = security_context_to_sid(mount_options[i], len, &sid);
2412                 if (rc) {
2413                         printk(KERN_WARNING "SELinux: security_context_to_sid"
2414                                "(%s) failed for (dev %s, type %s) errno=%d\n",
2415                                mount_options[i], sb->s_id, sb->s_type->name, rc);
2416                         goto out_free_opts;
2417                 }
2418                 rc = -EINVAL;
2419                 switch (flags[i]) {
2420                 case FSCONTEXT_MNT:
2421                         if (bad_option(sbsec, FSCONTEXT_MNT, sbsec->sid, sid))
2422                                 goto out_bad_option;
2423                         break;
2424                 case CONTEXT_MNT:
2425                         if (bad_option(sbsec, CONTEXT_MNT, sbsec->mntpoint_sid, sid))
2426                                 goto out_bad_option;
2427                         break;
2428                 case ROOTCONTEXT_MNT: {
2429                         struct inode_security_struct *root_isec;
2430                         root_isec = sb->s_root->d_inode->i_security;
2431
2432                         if (bad_option(sbsec, ROOTCONTEXT_MNT, root_isec->sid, sid))
2433                                 goto out_bad_option;
2434                         break;
2435                 }
2436                 case DEFCONTEXT_MNT:
2437                         if (bad_option(sbsec, DEFCONTEXT_MNT, sbsec->def_sid, sid))
2438                                 goto out_bad_option;
2439                         break;
2440                 default:
2441                         goto out_free_opts;
2442                 }
2443         }
2444
2445         rc = 0;
2446 out_free_opts:
2447         security_free_mnt_opts(&opts);
2448 out_free_secdata:
2449         free_secdata(secdata);
2450         return rc;
2451 out_bad_option:
2452         printk(KERN_WARNING "SELinux: unable to change security options "
2453                "during remount (dev %s, type=%s)\n", sb->s_id,
2454                sb->s_type->name);
2455         goto out_free_opts;
2456 }
2457
2458 static int selinux_sb_kern_mount(struct super_block *sb, int flags, void *data)
2459 {
2460         const struct cred *cred = current_cred();
2461         struct common_audit_data ad;
2462         int rc;
2463
2464         rc = superblock_doinit(sb, data);
2465         if (rc)
2466                 return rc;
2467
2468         /* Allow all mounts performed by the kernel */
2469         if (flags & MS_KERNMOUNT)
2470                 return 0;
2471
2472         ad.type = LSM_AUDIT_DATA_DENTRY;
2473         ad.u.dentry = sb->s_root;
2474         return superblock_has_perm(cred, sb, FILESYSTEM__MOUNT, &ad);
2475 }
2476
2477 static int selinux_sb_statfs(struct dentry *dentry)
2478 {
2479         const struct cred *cred = current_cred();
2480         struct common_audit_data ad;
2481
2482         ad.type = LSM_AUDIT_DATA_DENTRY;
2483         ad.u.dentry = dentry->d_sb->s_root;
2484         return superblock_has_perm(cred, dentry->d_sb, FILESYSTEM__GETATTR, &ad);
2485 }
2486
2487 static int selinux_mount(char *dev_name,
2488                          struct path *path,
2489                          char *type,
2490                          unsigned long flags,
2491                          void *data)
2492 {
2493         const struct cred *cred = current_cred();
2494
2495         if (flags & MS_REMOUNT)
2496                 return superblock_has_perm(cred, path->dentry->d_sb,
2497                                            FILESYSTEM__REMOUNT, NULL);
2498         else
2499                 return path_has_perm(cred, path, FILE__MOUNTON);
2500 }
2501
2502 static int selinux_umount(struct vfsmount *mnt, int flags)
2503 {
2504         const struct cred *cred = current_cred();
2505
2506         return superblock_has_perm(cred, mnt->mnt_sb,
2507                                    FILESYSTEM__UNMOUNT, NULL);
2508 }
2509
2510 /* inode security operations */
2511
2512 static int selinux_inode_alloc_security(struct inode *inode)
2513 {
2514         return inode_alloc_security(inode);
2515 }
2516
2517 static void selinux_inode_free_security(struct inode *inode)
2518 {
2519         inode_free_security(inode);
2520 }
2521
2522 static int selinux_inode_init_security(struct inode *inode, struct inode *dir,
2523                                        const struct qstr *qstr, char **name,
2524                                        void **value, size_t *len)
2525 {
2526         const struct task_security_struct *tsec = current_security();
2527         struct inode_security_struct *dsec;
2528         struct superblock_security_struct *sbsec;
2529         u32 sid, newsid, clen;
2530         int rc;
2531         char *namep = NULL, *context;
2532
2533         dsec = dir->i_security;
2534         sbsec = dir->i_sb->s_security;
2535
2536         sid = tsec->sid;
2537         newsid = tsec->create_sid;
2538
2539         if ((sbsec->flags & SE_SBINITIALIZED) &&
2540             (sbsec->behavior == SECURITY_FS_USE_MNTPOINT))
2541                 newsid = sbsec->mntpoint_sid;
2542         else if (!newsid || !(sbsec->flags & SE_SBLABELSUPP)) {
2543                 rc = security_transition_sid(sid, dsec->sid,
2544                                              inode_mode_to_security_class(inode->i_mode),
2545                                              qstr, &newsid);
2546                 if (rc) {
2547                         printk(KERN_WARNING "%s:  "
2548                                "security_transition_sid failed, rc=%d (dev=%s "
2549                                "ino=%ld)\n",
2550                                __func__,
2551                                -rc, inode->i_sb->s_id, inode->i_ino);
2552                         return rc;
2553                 }
2554         }
2555
2556         /* Possibly defer initialization to selinux_complete_init. */
2557         if (sbsec->flags & SE_SBINITIALIZED) {
2558                 struct inode_security_struct *isec = inode->i_security;
2559                 isec->sclass = inode_mode_to_security_class(inode->i_mode);
2560                 isec->sid = newsid;
2561                 isec->initialized = 1;
2562         }
2563
2564         if (!ss_initialized || !(sbsec->flags & SE_SBLABELSUPP))
2565                 return -EOPNOTSUPP;
2566
2567         if (name) {
2568                 namep = kstrdup(XATTR_SELINUX_SUFFIX, GFP_NOFS);
2569                 if (!namep)
2570                         return -ENOMEM;
2571                 *name = namep;
2572         }
2573
2574         if (value && len) {
2575                 rc = security_sid_to_context_force(newsid, &context, &clen);
2576                 if (rc) {
2577                         kfree(namep);
2578                         return rc;
2579                 }
2580                 *value = context;
2581                 *len = clen;
2582         }
2583
2584         return 0;
2585 }
2586
2587 static int selinux_inode_create(struct inode *dir, struct dentry *dentry, umode_t mode)
2588 {
2589         return may_create(dir, dentry, SECCLASS_FILE);
2590 }
2591
2592 static int selinux_inode_link(struct dentry *old_dentry, struct inode *dir, struct dentry *new_dentry)
2593 {
2594         return may_link(dir, old_dentry, MAY_LINK);
2595 }
2596
2597 static int selinux_inode_unlink(struct inode *dir, struct dentry *dentry)
2598 {
2599         return may_link(dir, dentry, MAY_UNLINK);
2600 }
2601
2602 static int selinux_inode_symlink(struct inode *dir, struct dentry *dentry, const char *name)
2603 {
2604         return may_create(dir, dentry, SECCLASS_LNK_FILE);
2605 }
2606
2607 static int selinux_inode_mkdir(struct inode *dir, struct dentry *dentry, umode_t mask)
2608 {
2609         return may_create(dir, dentry, SECCLASS_DIR);
2610 }
2611
2612 static int selinux_inode_rmdir(struct inode *dir, struct dentry *dentry)
2613 {
2614         return may_link(dir, dentry, MAY_RMDIR);
2615 }
2616
2617 static int selinux_inode_mknod(struct inode *dir, struct dentry *dentry, umode_t mode, dev_t dev)
2618 {
2619         return may_create(dir, dentry, inode_mode_to_security_class(mode));
2620 }
2621
2622 static int selinux_inode_rename(struct inode *old_inode, struct dentry *old_dentry,
2623                                 struct inode *new_inode, struct dentry *new_dentry)
2624 {
2625         return may_rename(old_inode, old_dentry, new_inode, new_dentry);
2626 }
2627
2628 static int selinux_inode_readlink(struct dentry *dentry)
2629 {
2630         const struct cred *cred = current_cred();
2631
2632         return dentry_has_perm(cred, dentry, FILE__READ);
2633 }
2634
2635 static int selinux_inode_follow_link(struct dentry *dentry, struct nameidata *nameidata)
2636 {
2637         const struct cred *cred = current_cred();
2638
2639         return dentry_has_perm(cred, dentry, FILE__READ);
2640 }
2641
2642 static noinline int audit_inode_permission(struct inode *inode,
2643                                            u32 perms, u32 audited, u32 denied,
2644                                            unsigned flags)
2645 {
2646         struct common_audit_data ad;
2647         struct inode_security_struct *isec = inode->i_security;
2648         int rc;
2649
2650         ad.type = LSM_AUDIT_DATA_INODE;
2651         ad.u.inode = inode;
2652
2653         rc = slow_avc_audit(current_sid(), isec->sid, isec->sclass, perms,
2654                             audited, denied, &ad, flags);
2655         if (rc)
2656                 return rc;
2657         return 0;
2658 }
2659
2660 static int selinux_inode_permission(struct inode *inode, int mask)
2661 {
2662         const struct cred *cred = current_cred();
2663         u32 perms;
2664         bool from_access;
2665         unsigned flags = mask & MAY_NOT_BLOCK;
2666         struct inode_security_struct *isec;
2667         u32 sid;
2668         struct av_decision avd;
2669         int rc, rc2;
2670         u32 audited, denied;
2671
2672         from_access = mask & MAY_ACCESS;
2673         mask &= (MAY_READ|MAY_WRITE|MAY_EXEC|MAY_APPEND);
2674
2675         /* No permission to check.  Existence test. */
2676         if (!mask)
2677                 return 0;
2678
2679         validate_creds(cred);
2680
2681         if (unlikely(IS_PRIVATE(inode)))
2682                 return 0;
2683
2684         perms = file_mask_to_av(inode->i_mode, mask);
2685
2686         sid = cred_sid(cred);
2687         isec = inode->i_security;
2688
2689         rc = avc_has_perm_noaudit(sid, isec->sid, isec->sclass, perms, 0, &avd);
2690         audited = avc_audit_required(perms, &avd, rc,
2691                                      from_access ? FILE__AUDIT_ACCESS : 0,
2692                                      &denied);
2693         if (likely(!audited))
2694                 return rc;
2695
2696         rc2 = audit_inode_permission(inode, perms, audited, denied, flags);
2697         if (rc2)
2698                 return rc2;
2699         return rc;
2700 }
2701
2702 static int selinux_inode_setattr(struct dentry *dentry, struct iattr *iattr)
2703 {
2704         const struct cred *cred = current_cred();
2705         unsigned int ia_valid = iattr->ia_valid;
2706         __u32 av = FILE__WRITE;
2707
2708         /* ATTR_FORCE is just used for ATTR_KILL_S[UG]ID. */
2709         if (ia_valid & ATTR_FORCE) {
2710                 ia_valid &= ~(ATTR_KILL_SUID | ATTR_KILL_SGID | ATTR_MODE |
2711                               ATTR_FORCE);
2712                 if (!ia_valid)
2713                         return 0;
2714         }
2715
2716         if (ia_valid & (ATTR_MODE | ATTR_UID | ATTR_GID |
2717                         ATTR_ATIME_SET | ATTR_MTIME_SET | ATTR_TIMES_SET))
2718                 return dentry_has_perm(cred, dentry, FILE__SETATTR);
2719
2720         if (ia_valid & ATTR_SIZE)
2721                 av |= FILE__OPEN;
2722
2723         return dentry_has_perm(cred, dentry, av);
2724 }
2725
2726 static int selinux_inode_getattr(struct vfsmount *mnt, struct dentry *dentry)
2727 {
2728         const struct cred *cred = current_cred();
2729         struct path path;
2730
2731         path.dentry = dentry;
2732         path.mnt = mnt;
2733
2734         return path_has_perm(cred, &path, FILE__GETATTR);
2735 }
2736
2737 static int selinux_inode_setotherxattr(struct dentry *dentry, const char *name)
2738 {
2739         const struct cred *cred = current_cred();
2740
2741         if (!strncmp(name, XATTR_SECURITY_PREFIX,
2742                      sizeof XATTR_SECURITY_PREFIX - 1)) {
2743                 if (!strcmp(name, XATTR_NAME_CAPS)) {
2744                         if (!capable(CAP_SETFCAP))
2745                                 return -EPERM;
2746                 } else if (!capable(CAP_SYS_ADMIN)) {
2747                         /* A different attribute in the security namespace.
2748                            Restrict to administrator. */
2749                         return -EPERM;
2750                 }
2751         }
2752
2753         /* Not an attribute we recognize, so just check the
2754            ordinary setattr permission. */
2755         return dentry_has_perm(cred, dentry, FILE__SETATTR);
2756 }
2757
2758 static int selinux_inode_setxattr(struct dentry *dentry, const char *name,
2759                                   const void *value, size_t size, int flags)
2760 {
2761         struct inode *inode = dentry->d_inode;
2762         struct inode_security_struct *isec = inode->i_security;
2763         struct superblock_security_struct *sbsec;
2764         struct common_audit_data ad;
2765         u32 newsid, sid = current_sid();
2766         int rc = 0;
2767
2768         if (strcmp(name, XATTR_NAME_SELINUX))
2769                 return selinux_inode_setotherxattr(dentry, name);
2770
2771         sbsec = inode->i_sb->s_security;
2772         if (!(sbsec->flags & SE_SBLABELSUPP))
2773                 return -EOPNOTSUPP;
2774
2775         if (!inode_owner_or_capable(inode))
2776                 return -EPERM;
2777
2778         ad.type = LSM_AUDIT_DATA_DENTRY;
2779         ad.u.dentry = dentry;
2780
2781         rc = avc_has_perm(sid, isec->sid, isec->sclass,
2782                           FILE__RELABELFROM, &ad);
2783         if (rc)
2784                 return rc;
2785
2786         rc = security_context_to_sid(value, size, &newsid);
2787         if (rc == -EINVAL) {
2788                 if (!capable(CAP_MAC_ADMIN)) {
2789                         struct audit_buffer *ab;
2790                         size_t audit_size;
2791                         const char *str;
2792
2793                         /* We strip a nul only if it is at the end, otherwise the
2794                          * context contains a nul and we should audit that */
2795                         str = value;
2796                         if (str[size - 1] == '\0')
2797                                 audit_size = size - 1;
2798                         else
2799                                 audit_size = size;
2800                         ab = audit_log_start(current->audit_context, GFP_ATOMIC, AUDIT_SELINUX_ERR);
2801                         audit_log_format(ab, "op=setxattr invalid_context=");
2802                         audit_log_n_untrustedstring(ab, value, audit_size);
2803                         audit_log_end(ab);
2804
2805                         return rc;
2806                 }
2807                 rc = security_context_to_sid_force(value, size, &newsid);
2808         }
2809         if (rc)
2810                 return rc;
2811
2812         rc = avc_has_perm(sid, newsid, isec->sclass,
2813                           FILE__RELABELTO, &ad);
2814         if (rc)
2815                 return rc;
2816
2817         rc = security_validate_transition(isec->sid, newsid, sid,
2818                                           isec->sclass);
2819         if (rc)
2820                 return rc;
2821
2822         return avc_has_perm(newsid,
2823                             sbsec->sid,
2824                             SECCLASS_FILESYSTEM,
2825                             FILESYSTEM__ASSOCIATE,
2826                             &ad);
2827 }
2828
2829 static void selinux_inode_post_setxattr(struct dentry *dentry, const char *name,
2830                                         const void *value, size_t size,
2831                                         int flags)
2832 {
2833         struct inode *inode = dentry->d_inode;
2834         struct inode_security_struct *isec = inode->i_security;
2835         u32 newsid;
2836         int rc;
2837
2838         if (strcmp(name, XATTR_NAME_SELINUX)) {
2839                 /* Not an attribute we recognize, so nothing to do. */
2840                 return;
2841         }
2842
2843         rc = security_context_to_sid_force(value, size, &newsid);
2844         if (rc) {
2845                 printk(KERN_ERR "SELinux:  unable to map context to SID"
2846                        "for (%s, %lu), rc=%d\n",
2847                        inode->i_sb->s_id, inode->i_ino, -rc);
2848                 return;
2849         }
2850
2851         isec->sid = newsid;
2852         return;
2853 }
2854
2855 static int selinux_inode_getxattr(struct dentry *dentry, const char *name)
2856 {
2857         const struct cred *cred = current_cred();
2858
2859         return dentry_has_perm(cred, dentry, FILE__GETATTR);
2860 }
2861
2862 static int selinux_inode_listxattr(struct dentry *dentry)
2863 {
2864         const struct cred *cred = current_cred();
2865
2866         return dentry_has_perm(cred, dentry, FILE__GETATTR);
2867 }
2868
2869 static int selinux_inode_removexattr(struct dentry *dentry, const char *name)
2870 {
2871         if (strcmp(name, XATTR_NAME_SELINUX))
2872                 return selinux_inode_setotherxattr(dentry, name);
2873
2874         /* No one is allowed to remove a SELinux security label.
2875            You can change the label, but all data must be labeled. */
2876         return -EACCES;
2877 }
2878
2879 /*
2880  * Copy the inode security context value to the user.
2881  *
2882  * Permission check is handled by selinux_inode_getxattr hook.
2883  */
2884 static int selinux_inode_getsecurity(const struct inode *inode, const char *name, void **buffer, bool alloc)
2885 {
2886         u32 size;
2887         int error;
2888         char *context = NULL;
2889         struct inode_security_struct *isec = inode->i_security;
2890
2891         if (strcmp(name, XATTR_SELINUX_SUFFIX))
2892                 return -EOPNOTSUPP;
2893
2894         /*
2895          * If the caller has CAP_MAC_ADMIN, then get the raw context
2896          * value even if it is not defined by current policy; otherwise,
2897          * use the in-core value under current policy.
2898          * Use the non-auditing forms of the permission checks since
2899          * getxattr may be called by unprivileged processes commonly
2900          * and lack of permission just means that we fall back to the
2901          * in-core context value, not a denial.
2902          */
2903         error = selinux_capable(current_cred(), &init_user_ns, CAP_MAC_ADMIN,
2904                                 SECURITY_CAP_NOAUDIT);
2905         if (!error)
2906                 error = security_sid_to_context_force(isec->sid, &context,
2907                                                       &size);
2908         else
2909                 error = security_sid_to_context(isec->sid, &context, &size);
2910         if (error)
2911                 return error;
2912         error = size;
2913         if (alloc) {
2914                 *buffer = context;
2915                 goto out_nofree;
2916         }
2917         kfree(context);
2918 out_nofree:
2919         return error;
2920 }
2921
2922 static int selinux_inode_setsecurity(struct inode *inode, const char *name,
2923                                      const void *value, size_t size, int flags)
2924 {
2925         struct inode_security_struct *isec = inode->i_security;
2926         u32 newsid;
2927         int rc;
2928
2929         if (strcmp(name, XATTR_SELINUX_SUFFIX))
2930                 return -EOPNOTSUPP;
2931
2932         if (!value || !size)
2933                 return -EACCES;
2934
2935         rc = security_context_to_sid((void *)value, size, &newsid);
2936         if (rc)
2937                 return rc;
2938
2939         isec->sid = newsid;
2940         isec->initialized = 1;
2941         return 0;
2942 }
2943
2944 static int selinux_inode_listsecurity(struct inode *inode, char *buffer, size_t buffer_size)
2945 {
2946         const int len = sizeof(XATTR_NAME_SELINUX);
2947         if (buffer && len <= buffer_size)
2948                 memcpy(buffer, XATTR_NAME_SELINUX, len);
2949         return len;
2950 }
2951
2952 static void selinux_inode_getsecid(const struct inode *inode, u32 *secid)
2953 {
2954         struct inode_security_struct *isec = inode->i_security;
2955         *secid = isec->sid;
2956 }
2957
2958 /* file security operations */
2959
2960 static int selinux_revalidate_file_permission(struct file *file, int mask)
2961 {
2962         const struct cred *cred = current_cred();
2963         struct inode *inode = file->f_path.dentry->d_inode;
2964
2965         /* file_mask_to_av won't add FILE__WRITE if MAY_APPEND is set */
2966         if ((file->f_flags & O_APPEND) && (mask & MAY_WRITE))
2967                 mask |= MAY_APPEND;
2968
2969         return file_has_perm(cred, file,
2970                              file_mask_to_av(inode->i_mode, mask));
2971 }
2972
2973 static int selinux_file_permission(struct file *file, int mask)
2974 {
2975         struct inode *inode = file->f_path.dentry->d_inode;
2976         struct file_security_struct *fsec = file->f_security;
2977         struct inode_security_struct *isec = inode->i_security;
2978         u32 sid = current_sid();
2979
2980         if (!mask)
2981                 /* No permission to check.  Existence test. */
2982                 return 0;
2983
2984         if (sid == fsec->sid && fsec->isid == isec->sid &&
2985             fsec->pseqno == avc_policy_seqno())
2986                 /* No change since file_open check. */
2987                 return 0;
2988
2989         return selinux_revalidate_file_permission(file, mask);
2990 }
2991
2992 static int selinux_file_alloc_security(struct file *file)
2993 {
2994         return file_alloc_security(file);
2995 }
2996
2997 static void selinux_file_free_security(struct file *file)
2998 {
2999         file_free_security(file);
3000 }
3001
3002 static int selinux_file_ioctl(struct file *file, unsigned int cmd,
3003                               unsigned long arg)
3004 {
3005         const struct cred *cred = current_cred();
3006         int error = 0;
3007
3008         switch (cmd) {
3009         case FIONREAD:
3010         /* fall through */
3011         case FIBMAP:
3012         /* fall through */
3013         case FIGETBSZ:
3014         /* fall through */
3015         case FS_IOC_GETFLAGS:
3016         /* fall through */
3017         case FS_IOC_GETVERSION:
3018                 error = file_has_perm(cred, file, FILE__GETATTR);
3019                 break;
3020
3021         case FS_IOC_SETFLAGS:
3022         /* fall through */
3023         case FS_IOC_SETVERSION:
3024                 error = file_has_perm(cred, file, FILE__SETATTR);
3025                 break;
3026
3027         /* sys_ioctl() checks */
3028         case FIONBIO:
3029         /* fall through */
3030         case FIOASYNC:
3031                 error = file_has_perm(cred, file, 0);
3032                 break;
3033
3034         case KDSKBENT:
3035         case KDSKBSENT:
3036                 error = cred_has_capability(cred, CAP_SYS_TTY_CONFIG,
3037                                             SECURITY_CAP_AUDIT);
3038                 break;
3039
3040         /* default case assumes that the command will go
3041          * to the file's ioctl() function.
3042          */
3043         default:
3044                 error = file_has_perm(cred, file, FILE__IOCTL);
3045         }
3046         return error;
3047 }
3048
3049 static int default_noexec;
3050
3051 static int file_map_prot_check(struct file *file, unsigned long prot, int shared)
3052 {
3053         const struct cred *cred = current_cred();
3054         int rc = 0;
3055
3056         if (default_noexec &&
3057             (prot & PROT_EXEC) && (!file || (!shared && (prot & PROT_WRITE)))) {
3058                 /*
3059                  * We are making executable an anonymous mapping or a
3060                  * private file mapping that will also be writable.
3061                  * This has an additional check.
3062                  */
3063                 rc = cred_has_perm(cred, cred, PROCESS__EXECMEM);
3064                 if (rc)
3065                         goto error;
3066         }
3067
3068         if (file) {
3069                 /* read access is always possible with a mapping */
3070                 u32 av = FILE__READ;
3071
3072                 /* write access only matters if the mapping is shared */
3073                 if (shared && (prot & PROT_WRITE))
3074                         av |= FILE__WRITE;
3075
3076                 if (prot & PROT_EXEC)
3077                         av |= FILE__EXECUTE;
3078
3079                 return file_has_perm(cred, file, av);
3080         }
3081
3082 error:
3083         return rc;
3084 }
3085
3086 static int selinux_mmap_addr(unsigned long addr)
3087 {
3088         int rc = 0;
3089         u32 sid = current_sid();
3090
3091         /*
3092          * notice that we are intentionally putting the SELinux check before
3093          * the secondary cap_file_mmap check.  This is such a likely attempt
3094          * at bad behaviour/exploit that we always want to get the AVC, even
3095          * if DAC would have also denied the operation.
3096          */
3097         if (addr < CONFIG_LSM_MMAP_MIN_ADDR) {
3098                 rc = avc_has_perm(sid, sid, SECCLASS_MEMPROTECT,
3099                                   MEMPROTECT__MMAP_ZERO, NULL);
3100                 if (rc)
3101                         return rc;
3102         }
3103
3104         /* do DAC check on address space usage */
3105         return cap_mmap_addr(addr);
3106 }
3107
3108 static int selinux_mmap_file(struct file *file, unsigned long reqprot,
3109                              unsigned long prot, unsigned long flags)
3110 {
3111         if (selinux_checkreqprot)
3112                 prot = reqprot;
3113
3114         return file_map_prot_check(file, prot,
3115                                    (flags & MAP_TYPE) == MAP_SHARED);
3116 }
3117
3118 static int selinux_file_mprotect(struct vm_area_struct *vma,
3119                                  unsigned long reqprot,
3120                                  unsigned long prot)
3121 {
3122         const struct cred *cred = current_cred();
3123
3124         if (selinux_checkreqprot)
3125                 prot = reqprot;
3126
3127         if (default_noexec &&
3128             (prot & PROT_EXEC) && !(vma->vm_flags & VM_EXEC)) {
3129                 int rc = 0;
3130                 if (vma->vm_start >= vma->vm_mm->start_brk &&
3131                     vma->vm_end <= vma->vm_mm->brk) {
3132                         rc = cred_has_perm(cred, cred, PROCESS__EXECHEAP);
3133                 } else if (!vma->vm_file &&
3134                            vma->vm_start <= vma->vm_mm->start_stack &&
3135                            vma->vm_end >= vma->vm_mm->start_stack) {
3136                         rc = current_has_perm(current, PROCESS__EXECSTACK);
3137                 } else if (vma->vm_file && vma->anon_vma) {
3138                         /*
3139                          * We are making executable a file mapping that has
3140                          * had some COW done. Since pages might have been
3141                          * written, check ability to execute the possibly
3142                          * modified content.  This typically should only
3143                          * occur for text relocations.
3144                          */
3145                         rc = file_has_perm(cred, vma->vm_file, FILE__EXECMOD);
3146                 }
3147                 if (rc)
3148                         return rc;
3149         }
3150
3151         return file_map_prot_check(vma->vm_file, prot, vma->vm_flags&VM_SHARED);
3152 }
3153
3154 static int selinux_file_lock(struct file *file, unsigned int cmd)
3155 {
3156         const struct cred *cred = current_cred();
3157
3158         return file_has_perm(cred, file, FILE__LOCK);
3159 }
3160
3161 static int selinux_file_fcntl(struct file *file, unsigned int cmd,
3162                               unsigned long arg)
3163 {
3164         const struct cred *cred = current_cred();
3165         int err = 0;
3166
3167         switch (cmd) {
3168         case F_SETFL:
3169                 if (!file->f_path.dentry || !file->f_path.dentry->d_inode) {
3170                         err = -EINVAL;
3171                         break;
3172                 }
3173
3174                 if ((file->f_flags & O_APPEND) && !(arg & O_APPEND)) {
3175                         err = file_has_perm(cred, file, FILE__WRITE);
3176                         break;
3177                 }
3178                 /* fall through */
3179         case F_SETOWN:
3180         case F_SETSIG:
3181         case F_GETFL:
3182         case F_GETOWN:
3183         case F_GETSIG:
3184                 /* Just check FD__USE permission */
3185                 err = file_has_perm(cred, file, 0);
3186                 break;
3187         case F_GETLK:
3188         case F_SETLK:
3189         case F_SETLKW:
3190 #if BITS_PER_LONG == 32
3191         case F_GETLK64:
3192         case F_SETLK64:
3193         case F_SETLKW64:
3194 #endif
3195                 if (!file->f_path.dentry || !file->f_path.dentry->d_inode) {
3196                         err = -EINVAL;
3197                         break;
3198                 }
3199                 err = file_has_perm(cred, file, FILE__LOCK);
3200                 break;
3201         }
3202
3203         return err;
3204 }
3205
3206 static int selinux_file_set_fowner(struct file *file)
3207 {
3208         struct file_security_struct *fsec;
3209
3210         fsec = file->f_security;
3211         fsec->fown_sid = current_sid();
3212
3213         return 0;
3214 }
3215
3216 static int selinux_file_send_sigiotask(struct task_struct *tsk,
3217                                        struct fown_struct *fown, int signum)
3218 {
3219         struct file *file;
3220         u32 sid = task_sid(tsk);
3221         u32 perm;
3222         struct file_security_struct *fsec;
3223
3224         /* struct fown_struct is never outside the context of a struct file */
3225         file = container_of(fown, struct file, f_owner);
3226
3227         fsec = file->f_security;
3228
3229         if (!signum)
3230                 perm = signal_to_av(SIGIO); /* as per send_sigio_to_task */
3231         else
3232                 perm = signal_to_av(signum);
3233
3234         return avc_has_perm(fsec->fown_sid, sid,
3235                             SECCLASS_PROCESS, perm, NULL);
3236 }
3237
3238 static int selinux_file_receive(struct file *file)
3239 {
3240         const struct cred *cred = current_cred();
3241
3242         return file_has_perm(cred, file, file_to_av(file));
3243 }
3244
3245 static int selinux_file_open(struct file *file, const struct cred *cred)
3246 {
3247         struct file_security_struct *fsec;
3248         struct inode_security_struct *isec;
3249
3250         fsec = file->f_security;
3251         isec = file->f_path.dentry->d_inode->i_security;
3252         /*
3253          * Save inode label and policy sequence number
3254          * at open-time so that selinux_file_permission
3255          * can determine whether revalidation is necessary.
3256          * Task label is already saved in the file security
3257          * struct as its SID.
3258          */
3259         fsec->isid = isec->sid;
3260         fsec->pseqno = avc_policy_seqno();
3261         /*
3262          * Since the inode label or policy seqno may have changed
3263          * between the selinux_inode_permission check and the saving
3264          * of state above, recheck that access is still permitted.
3265          * Otherwise, access might never be revalidated against the
3266          * new inode label or new policy.
3267          * This check is not redundant - do not remove.
3268          */
3269         return path_has_perm(cred, &file->f_path, open_file_to_av(file));
3270 }
3271
3272 /* task security operations */
3273
3274 static int selinux_task_create(unsigned long clone_flags)
3275 {
3276         return current_has_perm(current, PROCESS__FORK);
3277 }
3278
3279 /*
3280  * allocate the SELinux part of blank credentials
3281  */
3282 static int selinux_cred_alloc_blank(struct cred *cred, gfp_t gfp)
3283 {
3284         struct task_security_struct *tsec;
3285
3286         tsec = kzalloc(sizeof(struct task_security_struct), gfp);
3287         if (!tsec)
3288                 return -ENOMEM;
3289
3290         cred->security = tsec;
3291         return 0;
3292 }
3293
3294 /*
3295  * detach and free the LSM part of a set of credentials
3296  */
3297 static void selinux_cred_free(struct cred *cred)
3298 {
3299         struct task_security_struct *tsec = cred->security;
3300
3301         /*
3302          * cred->security == NULL if security_cred_alloc_blank() or
3303          * security_prepare_creds() returned an error.
3304          */
3305         BUG_ON(cred->security && (unsigned long) cred->security < PAGE_SIZE);
3306         cred->security = (void *) 0x7UL;
3307         kfree(tsec);
3308 }
3309
3310 /*
3311  * prepare a new set of credentials for modification
3312  */
3313 static int selinux_cred_prepare(struct cred *new, const struct cred *old,
3314                                 gfp_t gfp)
3315 {
3316         const struct task_security_struct *old_tsec;
3317         struct task_security_struct *tsec;
3318
3319         old_tsec = old->security;
3320
3321         tsec = kmemdup(old_tsec, sizeof(struct task_security_struct), gfp);
3322         if (!tsec)
3323                 return -ENOMEM;
3324
3325         new->security = tsec;
3326         return 0;
3327 }
3328
3329 /*
3330  * transfer the SELinux data to a blank set of creds
3331  */
3332 static void selinux_cred_transfer(struct cred *new, const struct cred *old)
3333 {
3334         const struct task_security_struct *old_tsec = old->security;
3335         struct task_security_struct *tsec = new->security;
3336
3337         *tsec = *old_tsec;
3338 }
3339
3340 /*
3341  * set the security data for a kernel service
3342  * - all the creation contexts are set to unlabelled
3343  */
3344 static int selinux_kernel_act_as(struct cred *new, u32 secid)
3345 {
3346         struct task_security_struct *tsec = new->security;
3347         u32 sid = current_sid();
3348         int ret;
3349
3350         ret = avc_has_perm(sid, secid,
3351                            SECCLASS_KERNEL_SERVICE,
3352                            KERNEL_SERVICE__USE_AS_OVERRIDE,
3353                            NULL);
3354         if (ret == 0) {
3355                 tsec->sid = secid;
3356                 tsec->create_sid = 0;
3357                 tsec->keycreate_sid = 0;
3358                 tsec->sockcreate_sid = 0;
3359         }
3360         return ret;
3361 }
3362
3363 /*
3364  * set the file creation context in a security record to the same as the
3365  * objective context of the specified inode
3366  */
3367 static int selinux_kernel_create_files_as(struct cred *new, struct inode *inode)
3368 {
3369         struct inode_security_struct *isec = inode->i_security;
3370         struct task_security_struct *tsec = new->security;
3371         u32 sid = current_sid();
3372         int ret;
3373
3374         ret = avc_has_perm(sid, isec->sid,
3375                            SECCLASS_KERNEL_SERVICE,
3376                            KERNEL_SERVICE__CREATE_FILES_AS,
3377                            NULL);
3378
3379         if (ret == 0)
3380                 tsec->create_sid = isec->sid;
3381         return ret;
3382 }
3383
3384 static int selinux_kernel_module_request(char *kmod_name)
3385 {
3386         u32 sid;
3387         struct common_audit_data ad;
3388
3389         sid = task_sid(current);
3390
3391         ad.type = LSM_AUDIT_DATA_KMOD;
3392         ad.u.kmod_name = kmod_name;
3393
3394         return avc_has_perm(sid, SECINITSID_KERNEL, SECCLASS_SYSTEM,
3395                             SYSTEM__MODULE_REQUEST, &ad);
3396 }
3397
3398 static int selinux_task_setpgid(struct task_struct *p, pid_t pgid)
3399 {
3400         return current_has_perm(p, PROCESS__SETPGID);
3401 }
3402
3403 static int selinux_task_getpgid(struct task_struct *p)
3404 {
3405         return current_has_perm(p, PROCESS__GETPGID);
3406 }
3407
3408 static int selinux_task_getsid(struct task_struct *p)
3409 {
3410         return current_has_perm(p, PROCESS__GETSESSION);
3411 }
3412
3413 static void selinux_task_getsecid(struct task_struct *p, u32 *secid)
3414 {
3415         *secid = task_sid(p);
3416 }
3417
3418 static int selinux_task_setnice(struct task_struct *p, int nice)
3419 {
3420         int rc;
3421
3422         rc = cap_task_setnice(p, nice);
3423         if (rc)
3424                 return rc;
3425
3426         return current_has_perm(p, PROCESS__SETSCHED);
3427 }
3428
3429 static int selinux_task_setioprio(struct task_struct *p, int ioprio)
3430 {
3431         int rc;
3432
3433         rc = cap_task_setioprio(p, ioprio);
3434         if (rc)
3435                 return rc;
3436
3437         return current_has_perm(p, PROCESS__SETSCHED);
3438 }
3439
3440 static int selinux_task_getioprio(struct task_struct *p)
3441 {
3442         return current_has_perm(p, PROCESS__GETSCHED);
3443 }
3444
3445 static int selinux_task_setrlimit(struct task_struct *p, unsigned int resource,
3446                 struct rlimit *new_rlim)
3447 {
3448         struct rlimit *old_rlim = p->signal->rlim + resource;
3449
3450         /* Control the ability to change the hard limit (whether
3451            lowering or raising it), so that the hard limit can
3452            later be used as a safe reset point for the soft limit
3453            upon context transitions.  See selinux_bprm_committing_creds. */
3454         if (old_rlim->rlim_max != new_rlim->rlim_max)
3455                 return current_has_perm(p, PROCESS__SETRLIMIT);
3456
3457         return 0;
3458 }
3459
3460 static int selinux_task_setscheduler(struct task_struct *p)
3461 {
3462         int rc;
3463
3464         rc = cap_task_setscheduler(p);
3465         if (rc)
3466                 return rc;
3467
3468         return current_has_perm(p, PROCESS__SETSCHED);
3469 }
3470
3471 static int selinux_task_getscheduler(struct task_struct *p)
3472 {
3473         return current_has_perm(p, PROCESS__GETSCHED);
3474 }
3475
3476 static int selinux_task_movememory(struct task_struct *p)
3477 {
3478         return current_has_perm(p, PROCESS__SETSCHED);
3479 }
3480
3481 static int selinux_task_kill(struct task_struct *p, struct siginfo *info,
3482                                 int sig, u32 secid)
3483 {
3484         u32 perm;
3485         int rc;
3486
3487         if (!sig)
3488                 perm = PROCESS__SIGNULL; /* null signal; existence test */
3489         else
3490                 perm = signal_to_av(sig);
3491         if (secid)
3492                 rc = avc_has_perm(secid, task_sid(p),
3493                                   SECCLASS_PROCESS, perm, NULL);
3494         else
3495                 rc = current_has_perm(p, perm);
3496         return rc;
3497 }
3498
3499 static int selinux_task_wait(struct task_struct *p)
3500 {
3501         return task_has_perm(p, current, PROCESS__SIGCHLD);
3502 }
3503
3504 static void selinux_task_to_inode(struct task_struct *p,
3505                                   struct inode *inode)
3506 {
3507         struct inode_security_struct *isec = inode->i_security;
3508         u32 sid = task_sid(p);
3509
3510         isec->sid = sid;
3511         isec->initialized = 1;
3512 }
3513
3514 /* Returns error only if unable to parse addresses */
3515 static int selinux_parse_skb_ipv4(struct sk_buff *skb,
3516                         struct common_audit_data *ad, u8 *proto)
3517 {
3518         int offset, ihlen, ret = -EINVAL;
3519         struct iphdr _iph, *ih;
3520
3521         offset = skb_network_offset(skb);
3522         ih = skb_header_pointer(skb, offset, sizeof(_iph), &_iph);
3523         if (ih == NULL)
3524                 goto out;
3525
3526         ihlen = ih->ihl * 4;
3527         if (ihlen < sizeof(_iph))
3528                 goto out;
3529
3530         ad->u.net->v4info.saddr = ih->saddr;
3531         ad->u.net->v4info.daddr = ih->daddr;
3532         ret = 0;
3533
3534         if (proto)
3535                 *proto = ih->protocol;
3536
3537         switch (ih->protocol) {
3538         case IPPROTO_TCP: {
3539                 struct tcphdr _tcph, *th;
3540
3541                 if (ntohs(ih->frag_off) & IP_OFFSET)
3542                         break;
3543
3544                 offset += ihlen;
3545                 th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph);
3546                 if (th == NULL)
3547                         break;
3548
3549                 ad->u.net->sport = th->source;
3550                 ad->u.net->dport = th->dest;
3551                 break;
3552         }
3553
3554         case IPPROTO_UDP: {
3555                 struct udphdr _udph, *uh;
3556
3557                 if (ntohs(ih->frag_off) & IP_OFFSET)
3558                         break;
3559
3560                 offset += ihlen;
3561                 uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph);
3562                 if (uh == NULL)
3563                         break;
3564
3565                 ad->u.net->sport = uh->source;
3566                 ad->u.net->dport = uh->dest;
3567                 break;
3568         }
3569
3570         case IPPROTO_DCCP: {
3571                 struct dccp_hdr _dccph, *dh;
3572
3573                 if (ntohs(ih->frag_off) & IP_OFFSET)
3574                         break;
3575
3576                 offset += ihlen;
3577                 dh = skb_header_pointer(skb, offset, sizeof(_dccph), &_dccph);
3578                 if (dh == NULL)
3579                         break;
3580
3581                 ad->u.net->sport = dh->dccph_sport;
3582                 ad->u.net->dport = dh->dccph_dport;
3583                 break;
3584         }
3585
3586         default:
3587                 break;
3588         }
3589 out:
3590         return ret;
3591 }
3592
3593 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
3594
3595 /* Returns error only if unable to parse addresses */
3596 static int selinux_parse_skb_ipv6(struct sk_buff *skb,
3597                         struct common_audit_data *ad, u8 *proto)
3598 {
3599         u8 nexthdr;
3600         int ret = -EINVAL, offset;
3601         struct ipv6hdr _ipv6h, *ip6;
3602         __be16 frag_off;
3603
3604         offset = skb_network_offset(skb);
3605         ip6 = skb_header_pointer(skb, offset, sizeof(_ipv6h), &_ipv6h);
3606         if (ip6 == NULL)
3607                 goto out;
3608
3609         ad->u.net->v6info.saddr = ip6->saddr;
3610         ad->u.net->v6info.daddr = ip6->daddr;
3611         ret = 0;
3612
3613         nexthdr = ip6->nexthdr;
3614         offset += sizeof(_ipv6h);
3615         offset = ipv6_skip_exthdr(skb, offset, &nexthdr, &frag_off);
3616         if (offset < 0)
3617                 goto out;
3618
3619         if (proto)
3620                 *proto = nexthdr;
3621
3622         switch (nexthdr) {
3623         case IPPROTO_TCP: {
3624                 struct tcphdr _tcph, *th;
3625
3626                 th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph);
3627                 if (th == NULL)
3628                         break;
3629
3630                 ad->u.net->sport = th->source;
3631                 ad->u.net->dport = th->dest;
3632                 break;
3633         }
3634
3635         case IPPROTO_UDP: {
3636                 struct udphdr _udph, *uh;
3637
3638                 uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph);
3639                 if (uh == NULL)
3640                         break;
3641
3642                 ad->u.net->sport = uh->source;
3643                 ad->u.net->dport = uh->dest;
3644                 break;
3645         }
3646
3647         case IPPROTO_DCCP: {
3648                 struct dccp_hdr _dccph, *dh;
3649
3650                 dh = skb_header_pointer(skb, offset, sizeof(_dccph), &_dccph);
3651                 if (dh == NULL)
3652                         break;
3653
3654                 ad->u.net->sport = dh->dccph_sport;
3655                 ad->u.net->dport = dh->dccph_dport;
3656                 break;
3657         }
3658
3659         /* includes fragments */
3660         default:
3661                 break;
3662         }
3663 out:
3664         return ret;
3665 }
3666
3667 #endif /* IPV6 */
3668
3669 static int selinux_parse_skb(struct sk_buff *skb, struct common_audit_data *ad,
3670                              char **_addrp, int src, u8 *proto)
3671 {
3672         char *addrp;
3673         int ret;
3674
3675         switch (ad->u.net->family) {
3676         case PF_INET:
3677                 ret = selinux_parse_skb_ipv4(skb, ad, proto);
3678                 if (ret)
3679                         goto parse_error;
3680                 addrp = (char *)(src ? &ad->u.net->v4info.saddr :
3681                                        &ad->u.net->v4info.daddr);
3682                 goto okay;
3683
3684 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
3685         case PF_INET6:
3686                 ret = selinux_parse_skb_ipv6(skb, ad, proto);
3687                 if (ret)
3688                         goto parse_error;
3689                 addrp = (char *)(src ? &ad->u.net->v6info.saddr :
3690                                        &ad->u.net->v6info.daddr);
3691                 goto okay;
3692 #endif  /* IPV6 */
3693         default:
3694                 addrp = NULL;
3695                 goto okay;
3696         }
3697
3698 parse_error:
3699         printk(KERN_WARNING
3700                "SELinux: failure in selinux_parse_skb(),"
3701                " unable to parse packet\n");
3702         return ret;
3703
3704 okay:
3705         if (_addrp)
3706                 *_addrp = addrp;
3707         return 0;
3708 }
3709
3710 /**
3711  * selinux_skb_peerlbl_sid - Determine the peer label of a packet
3712  * @skb: the packet
3713  * @family: protocol family
3714  * @sid: the packet's peer label SID
3715  *
3716  * Description:
3717  * Check the various different forms of network peer labeling and determine
3718  * the peer label/SID for the packet; most of the magic actually occurs in
3719  * the security server function security_net_peersid_cmp().  The function
3720  * returns zero if the value in @sid is valid (although it may be SECSID_NULL)
3721  * or -EACCES if @sid is invalid due to inconsistencies with the different
3722  * peer labels.
3723  *
3724  */
3725 static int selinux_skb_peerlbl_sid(struct sk_buff *skb, u16 family, u32 *sid)
3726 {
3727         int err;
3728         u32 xfrm_sid;
3729         u32 nlbl_sid;
3730         u32 nlbl_type;
3731
3732         selinux_skb_xfrm_sid(skb, &xfrm_sid);
3733         selinux_netlbl_skbuff_getsid(skb, family, &nlbl_type, &nlbl_sid);
3734
3735         err = security_net_peersid_resolve(nlbl_sid, nlbl_type, xfrm_sid, sid);
3736         if (unlikely(err)) {
3737                 printk(KERN_WARNING
3738                        "SELinux: failure in selinux_skb_peerlbl_sid(),"
3739                        " unable to determine packet's peer label\n");
3740                 return -EACCES;
3741         }
3742
3743         return 0;
3744 }
3745
3746 /* socket security operations */
3747
3748 static int socket_sockcreate_sid(const struct task_security_struct *tsec,
3749                                  u16 secclass, u32 *socksid)
3750 {
3751         if (tsec->sockcreate_sid > SECSID_NULL) {
3752                 *socksid = tsec->sockcreate_sid;
3753                 return 0;
3754         }
3755
3756         return security_transition_sid(tsec->sid, tsec->sid, secclass, NULL,
3757                                        socksid);
3758 }
3759
3760 static int sock_has_perm(struct task_struct *task, struct sock *sk, u32 perms)
3761 {
3762         struct sk_security_struct *sksec = sk->sk_security;
3763         struct common_audit_data ad;
3764         struct lsm_network_audit net = {0,};
3765         u32 tsid = task_sid(task);
3766
3767         if (sksec->sid == SECINITSID_KERNEL)
3768                 return 0;
3769
3770         ad.type = LSM_AUDIT_DATA_NET;
3771         ad.u.net = &net;
3772         ad.u.net->sk = sk;
3773
3774         return avc_has_perm(tsid, sksec->sid, sksec->sclass, perms, &ad);
3775 }
3776
3777 static int selinux_socket_create(int family, int type,
3778                                  int protocol, int kern)
3779 {
3780         const struct task_security_struct *tsec = current_security();
3781         u32 newsid;
3782         u16 secclass;
3783         int rc;
3784
3785         if (kern)
3786                 return 0;
3787
3788         secclass = socket_type_to_security_class(family, type, protocol);
3789         rc = socket_sockcreate_sid(tsec, secclass, &newsid);
3790         if (rc)
3791                 return rc;
3792
3793         return avc_has_perm(tsec->sid, newsid, secclass, SOCKET__CREATE, NULL);
3794 }
3795
3796 static int selinux_socket_post_create(struct socket *sock, int family,
3797                                       int type, int protocol, int kern)
3798 {
3799         const struct task_security_struct *tsec = current_security();
3800         struct inode_security_struct *isec = SOCK_INODE(sock)->i_security;
3801         struct sk_security_struct *sksec;
3802         int err = 0;
3803
3804         isec->sclass = socket_type_to_security_class(family, type, protocol);
3805
3806         if (kern)
3807                 isec->sid = SECINITSID_KERNEL;
3808         else {
3809                 err = socket_sockcreate_sid(tsec, isec->sclass, &(isec->sid));
3810                 if (err)
3811                         return err;
3812         }
3813
3814         isec->initialized = 1;
3815
3816         if (sock->sk) {
3817                 sksec = sock->sk->sk_security;
3818                 sksec->sid = isec->sid;
3819                 sksec->sclass = isec->sclass;
3820                 err = selinux_netlbl_socket_post_create(sock->sk, family);
3821         }
3822
3823         return err;
3824 }
3825
3826 /* Range of port numbers used to automatically bind.
3827    Need to determine whether we should perform a name_bind
3828    permission check between the socket and the port number. */
3829
3830 static int selinux_socket_bind(struct socket *sock, struct sockaddr *address, int addrlen)
3831 {
3832         struct sock *sk = sock->sk;
3833         u16 family;
3834         int err;
3835
3836         err = sock_has_perm(current, sk, SOCKET__BIND);
3837         if (err)
3838                 goto out;
3839
3840         /*
3841          * If PF_INET or PF_INET6, check name_bind permission for the port.
3842          * Multiple address binding for SCTP is not supported yet: we just
3843          * check the first address now.
3844          */
3845         family = sk->sk_family;
3846         if (family == PF_INET || family == PF_INET6) {
3847                 char *addrp;
3848                 struct sk_security_struct *sksec = sk->sk_security;
3849                 struct common_audit_data ad;
3850                 struct lsm_network_audit net = {0,};
3851                 struct sockaddr_in *addr4 = NULL;
3852                 struct sockaddr_in6 *addr6 = NULL;
3853                 unsigned short snum;
3854                 u32 sid, node_perm;
3855
3856                 if (family == PF_INET) {
3857                         addr4 = (struct sockaddr_in *)address;
3858                         snum = ntohs(addr4->sin_port);
3859                         addrp = (char *)&addr4->sin_addr.s_addr;
3860                 } else {
3861                         addr6 = (struct sockaddr_in6 *)address;
3862                         snum = ntohs(addr6->sin6_port);
3863                         addrp = (char *)&addr6->sin6_addr.s6_addr;
3864                 }
3865
3866                 if (snum) {
3867                         int low, high;
3868
3869                         inet_get_local_port_range(&low, &high);
3870
3871                         if (snum < max(PROT_SOCK, low) || snum > high) {
3872                                 err = sel_netport_sid(sk->sk_protocol,
3873                                                       snum, &sid);
3874                                 if (err)
3875                                         goto out;
3876                                 ad.type = LSM_AUDIT_DATA_NET;
3877                                 ad.u.net = &net;
3878                                 ad.u.net->sport = htons(snum);
3879                                 ad.u.net->family = family;
3880                                 err = avc_has_perm(sksec->sid, sid,
3881                                                    sksec->sclass,
3882                                                    SOCKET__NAME_BIND, &ad);
3883                                 if (err)
3884                                         goto out;
3885                         }
3886                 }
3887
3888                 switch (sksec->sclass) {
3889                 case SECCLASS_TCP_SOCKET:
3890                         node_perm = TCP_SOCKET__NODE_BIND;
3891                         break;
3892
3893                 case SECCLASS_UDP_SOCKET:
3894                         node_perm = UDP_SOCKET__NODE_BIND;
3895                         break;
3896
3897                 case SECCLASS_DCCP_SOCKET:
3898                         node_perm = DCCP_SOCKET__NODE_BIND;
3899                         break;
3900
3901                 default:
3902                         node_perm = RAWIP_SOCKET__NODE_BIND;
3903                         break;
3904                 }
3905
3906                 err = sel_netnode_sid(addrp, family, &sid);
3907                 if (err)
3908                         goto out;
3909
3910                 ad.type = LSM_AUDIT_DATA_NET;
3911                 ad.u.net = &net;
3912                 ad.u.net->sport = htons(snum);
3913                 ad.u.net->family = family;
3914
3915                 if (family == PF_INET)
3916                         ad.u.net->v4info.saddr = addr4->sin_addr.s_addr;
3917                 else
3918                         ad.u.net->v6info.saddr = addr6->sin6_addr;
3919
3920                 err = avc_has_perm(sksec->sid, sid,
3921                                    sksec->sclass, node_perm, &ad);
3922                 if (err)
3923                         goto out;
3924         }
3925 out:
3926         return err;
3927 }
3928
3929 static int selinux_socket_connect(struct socket *sock, struct sockaddr *address, int addrlen)
3930 {
3931         struct sock *sk = sock->sk;
3932         struct sk_security_struct *sksec = sk->sk_security;
3933         int err;
3934
3935         err = sock_has_perm(current, sk, SOCKET__CONNECT);
3936         if (err)
3937                 return err;
3938
3939         /*
3940          * If a TCP or DCCP socket, check name_connect permission for the port.
3941          */
3942         if (sksec->sclass == SECCLASS_TCP_SOCKET ||
3943             sksec->sclass == SECCLASS_DCCP_SOCKET) {
3944                 struct common_audit_data ad;
3945                 struct lsm_network_audit net = {0,};
3946                 struct sockaddr_in *addr4 = NULL;
3947                 struct sockaddr_in6 *addr6 = NULL;
3948                 unsigned short snum;
3949                 u32 sid, perm;
3950
3951                 if (sk->sk_family == PF_INET) {
3952                         addr4 = (struct sockaddr_in *)address;
3953                         if (addrlen < sizeof(struct sockaddr_in))
3954                                 return -EINVAL;
3955                         snum = ntohs(addr4->sin_port);
3956                 } else {
3957                         addr6 = (struct sockaddr_in6 *)address;
3958                         if (addrlen < SIN6_LEN_RFC2133)
3959                                 return -EINVAL;
3960                         snum = ntohs(addr6->sin6_port);
3961                 }
3962
3963                 err = sel_netport_sid(sk->sk_protocol, snum, &sid);
3964                 if (err)
3965                         goto out;
3966
3967                 perm = (sksec->sclass == SECCLASS_TCP_SOCKET) ?
3968                        TCP_SOCKET__NAME_CONNECT : DCCP_SOCKET__NAME_CONNECT;
3969
3970                 ad.type = LSM_AUDIT_DATA_NET;
3971                 ad.u.net = &net;
3972                 ad.u.net->dport = htons(snum);
3973                 ad.u.net->family = sk->sk_family;
3974                 err = avc_has_perm(sksec->sid, sid, sksec->sclass, perm, &ad);
3975                 if (err)
3976                         goto out;
3977         }
3978
3979         err = selinux_netlbl_socket_connect(sk, address);
3980
3981 out:
3982         return err;
3983 }
3984
3985 static int selinux_socket_listen(struct socket *sock, int backlog)
3986 {
3987         return sock_has_perm(current, sock->sk, SOCKET__LISTEN);
3988 }
3989
3990 static int selinux_socket_accept(struct socket *sock, struct socket *newsock)
3991 {
3992         int err;
3993         struct inode_security_struct *isec;
3994         struct inode_security_struct *newisec;
3995
3996         err = sock_has_perm(current, sock->sk, SOCKET__ACCEPT);
3997         if (err)
3998                 return err;
3999
4000         newisec = SOCK_INODE(newsock)->i_security;
4001
4002         isec = SOCK_INODE(sock)->i_security;
4003         newisec->sclass = isec->sclass;
4004         newisec->sid = isec->sid;
4005         newisec->initialized = 1;
4006
4007         return 0;
4008 }
4009
4010 static int selinux_socket_sendmsg(struct socket *sock, struct msghdr *msg,
4011                                   int size)
4012 {
4013         return sock_has_perm(current, sock->sk, SOCKET__WRITE);
4014 }
4015
4016 static int selinux_socket_recvmsg(struct socket *sock, struct msghdr *msg,
4017                                   int size, int flags)
4018 {
4019         return sock_has_perm(current, sock->sk, SOCKET__READ);
4020 }
4021
4022 static int selinux_socket_getsockname(struct socket *sock)
4023 {
4024         return sock_has_perm(current, sock->sk, SOCKET__GETATTR);
4025 }
4026
4027 static int selinux_socket_getpeername(struct socket *sock)
4028 {
4029         return sock_has_perm(current, sock->sk, SOCKET__GETATTR);
4030 }
4031
4032 static int selinux_socket_setsockopt(struct socket *sock, int level, int optname)
4033 {
4034         int err;
4035
4036         err = sock_has_perm(current, sock->sk, SOCKET__SETOPT);
4037         if (err)
4038                 return err;
4039
4040         return selinux_netlbl_socket_setsockopt(sock, level, optname);
4041 }
4042
4043 static int selinux_socket_getsockopt(struct socket *sock, int level,
4044                                      int optname)
4045 {
4046         return sock_has_perm(current, sock->sk, SOCKET__GETOPT);
4047 }
4048
4049 static int selinux_socket_shutdown(struct socket *sock, int how)
4050 {
4051         return sock_has_perm(current, sock->sk, SOCKET__SHUTDOWN);
4052 }
4053
4054 static int selinux_socket_unix_stream_connect(struct sock *sock,
4055                                               struct sock *other,
4056                                               struct sock *newsk)
4057 {
4058         struct sk_security_struct *sksec_sock = sock->sk_security;
4059         struct sk_security_struct *sksec_other = other->sk_security;
4060         struct sk_security_struct *sksec_new = newsk->sk_security;
4061         struct common_audit_data ad;
4062         struct lsm_network_audit net = {0,};
4063         int err;
4064
4065         ad.type = LSM_AUDIT_DATA_NET;
4066         ad.u.net = &net;
4067         ad.u.net->sk = other;
4068
4069         err = avc_has_perm(sksec_sock->sid, sksec_other->sid,
4070                            sksec_other->sclass,
4071                            UNIX_STREAM_SOCKET__CONNECTTO, &ad);
4072         if (err)
4073                 return err;
4074
4075         /* server child socket */
4076         sksec_new->peer_sid = sksec_sock->sid;
4077         err = security_sid_mls_copy(sksec_other->sid, sksec_sock->sid,
4078                                     &sksec_new->sid);
4079         if (err)
4080                 return err;
4081
4082         /* connecting socket */
4083         sksec_sock->peer_sid = sksec_new->sid;
4084
4085         return 0;
4086 }
4087
4088 static int selinux_socket_unix_may_send(struct socket *sock,
4089                                         struct socket *other)
4090 {
4091         struct sk_security_struct *ssec = sock->sk->sk_security;
4092         struct sk_security_struct *osec = other->sk->sk_security;
4093         struct common_audit_data ad;
4094         struct lsm_network_audit net = {0,};
4095
4096         ad.type = LSM_AUDIT_DATA_NET;
4097         ad.u.net = &net;
4098         ad.u.net->sk = other->sk;
4099
4100         return avc_has_perm(ssec->sid, osec->sid, osec->sclass, SOCKET__SENDTO,
4101                             &ad);
4102 }
4103
4104 static int selinux_inet_sys_rcv_skb(int ifindex, char *addrp, u16 family,
4105                                     u32 peer_sid,
4106                                     struct common_audit_data *ad)
4107 {
4108         int err;
4109         u32 if_sid;
4110         u32 node_sid;
4111
4112         err = sel_netif_sid(ifindex, &if_sid);
4113         if (err)
4114                 return err;
4115         err = avc_has_perm(peer_sid, if_sid,
4116                            SECCLASS_NETIF, NETIF__INGRESS, ad);
4117         if (err)
4118                 return err;
4119
4120         err = sel_netnode_sid(addrp, family, &node_sid);
4121         if (err)
4122                 return err;
4123         return avc_has_perm(peer_sid, node_sid,
4124                             SECCLASS_NODE, NODE__RECVFROM, ad);
4125 }
4126
4127 static int selinux_sock_rcv_skb_compat(struct sock *sk, struct sk_buff *skb,
4128                                        u16 family)
4129 {
4130         int err = 0;
4131         struct sk_security_struct *sksec = sk->sk_security;
4132         u32 sk_sid = sksec->sid;
4133         struct common_audit_data ad;
4134         struct lsm_network_audit net = {0,};
4135         char *addrp;
4136
4137         ad.type = LSM_AUDIT_DATA_NET;
4138         ad.u.net = &net;
4139         ad.u.net->netif = skb->skb_iif;
4140         ad.u.net->family = family;
4141         err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL);
4142         if (err)
4143                 return err;
4144
4145         if (selinux_secmark_enabled()) {
4146                 err = avc_has_perm(sk_sid, skb->secmark, SECCLASS_PACKET,
4147                                    PACKET__RECV, &ad);
4148                 if (err)
4149                         return err;
4150         }
4151
4152         err = selinux_netlbl_sock_rcv_skb(sksec, skb, family, &ad);
4153         if (err)
4154                 return err;
4155         err = selinux_xfrm_sock_rcv_skb(sksec->sid, skb, &ad);
4156
4157         return err;
4158 }
4159
4160 static int selinux_socket_sock_rcv_skb(struct sock *sk, struct sk_buff *skb)
4161 {
4162         int err;
4163         struct sk_security_struct *sksec = sk->sk_security;
4164         u16 family = sk->sk_family;
4165         u32 sk_sid = sksec->sid;
4166         struct common_audit_data ad;
4167         struct lsm_network_audit net = {0,};
4168         char *addrp;
4169         u8 secmark_active;
4170         u8 peerlbl_active;
4171
4172         if (family != PF_INET && family != PF_INET6)
4173                 return 0;
4174
4175         /* Handle mapped IPv4 packets arriving via IPv6 sockets */
4176         if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
4177                 family = PF_INET;
4178
4179         /* If any sort of compatibility mode is enabled then handoff processing
4180          * to the selinux_sock_rcv_skb_compat() function to deal with the
4181          * special handling.  We do this in an attempt to keep this function
4182          * as fast and as clean as possible. */
4183         if (!selinux_policycap_netpeer)
4184                 return selinux_sock_rcv_skb_compat(sk, skb, family);
4185
4186         secmark_active = selinux_secmark_enabled();
4187         peerlbl_active = netlbl_enabled() || selinux_xfrm_enabled();
4188         if (!secmark_active && !peerlbl_active)
4189                 return 0;
4190
4191         ad.type = LSM_AUDIT_DATA_NET;
4192         ad.u.net = &net;
4193         ad.u.net->netif = skb->skb_iif;
4194         ad.u.net->family = family;
4195         err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL);
4196         if (err)
4197                 return err;
4198
4199         if (peerlbl_active) {
4200                 u32 peer_sid;
4201
4202                 err = selinux_skb_peerlbl_sid(skb, family, &peer_sid);
4203                 if (err)
4204                         return err;
4205                 err = selinux_inet_sys_rcv_skb(skb->skb_iif, addrp, family,
4206                                                peer_sid, &ad);
4207                 if (err) {
4208                         selinux_netlbl_err(skb, err, 0);
4209                         return err;
4210                 }
4211                 err = avc_has_perm(sk_sid, peer_sid, SECCLASS_PEER,
4212                                    PEER__RECV, &ad);
4213                 if (err)
4214                         selinux_netlbl_err(skb, err, 0);
4215         }
4216
4217         if (secmark_active) {
4218                 err = avc_has_perm(sk_sid, skb->secmark, SECCLASS_PACKET,
4219                                    PACKET__RECV, &ad);
4220                 if (err)
4221                         return err;
4222         }
4223
4224         return err;
4225 }
4226
4227 static int selinux_socket_getpeersec_stream(struct socket *sock, char __user *optval,
4228                                             int __user *optlen, unsigned len)
4229 {
4230         int err = 0;
4231         char *scontext;
4232         u32 scontext_len;
4233         struct sk_security_struct *sksec = sock->sk->sk_security;
4234         u32 peer_sid = SECSID_NULL;
4235
4236         if (sksec->sclass == SECCLASS_UNIX_STREAM_SOCKET ||
4237             sksec->sclass == SECCLASS_TCP_SOCKET)
4238                 peer_sid = sksec->peer_sid;
4239         if (peer_sid == SECSID_NULL)
4240                 return -ENOPROTOOPT;
4241
4242         err = security_sid_to_context(peer_sid, &scontext, &scontext_len);
4243         if (err)
4244                 return err;
4245
4246         if (scontext_len > len) {
4247                 err = -ERANGE;
4248                 goto out_len;
4249         }
4250
4251         if (copy_to_user(optval, scontext, scontext_len))
4252                 err = -EFAULT;
4253
4254 out_len:
4255         if (put_user(scontext_len, optlen))
4256                 err = -EFAULT;
4257         kfree(scontext);
4258         return err;
4259 }
4260
4261 static int selinux_socket_getpeersec_dgram(struct socket *sock, struct sk_buff *skb, u32 *secid)
4262 {
4263         u32 peer_secid = SECSID_NULL;
4264         u16 family;
4265
4266         if (skb && skb->protocol == htons(ETH_P_IP))
4267                 family = PF_INET;
4268         else if (skb && skb->protocol == htons(ETH_P_IPV6))
4269                 family = PF_INET6;
4270         else if (sock)
4271                 family = sock->sk->sk_family;
4272         else
4273                 goto out;
4274
4275         if (sock && family == PF_UNIX)
4276                 selinux_inode_getsecid(SOCK_INODE(sock), &peer_secid);
4277         else if (skb)
4278                 selinux_skb_peerlbl_sid(skb, family, &peer_secid);
4279
4280 out:
4281         *secid = peer_secid;
4282         if (peer_secid == SECSID_NULL)
4283                 return -EINVAL;
4284         return 0;
4285 }
4286
4287 static int selinux_sk_alloc_security(struct sock *sk, int family, gfp_t priority)
4288 {
4289         struct sk_security_struct *sksec;
4290
4291         sksec = kzalloc(sizeof(*sksec), priority);
4292         if (!sksec)
4293                 return -ENOMEM;
4294
4295         sksec->peer_sid = SECINITSID_UNLABELED;
4296         sksec->sid = SECINITSID_UNLABELED;
4297         selinux_netlbl_sk_security_reset(sksec);
4298         sk->sk_security = sksec;
4299
4300         return 0;
4301 }
4302
4303 static void selinux_sk_free_security(struct sock *sk)
4304 {
4305         struct sk_security_struct *sksec = sk->sk_security;
4306
4307         sk->sk_security = NULL;
4308         selinux_netlbl_sk_security_free(sksec);
4309         kfree(sksec);
4310 }
4311
4312 static void selinux_sk_clone_security(const struct sock *sk, struct sock *newsk)
4313 {
4314         struct sk_security_struct *sksec = sk->sk_security;
4315         struct sk_security_struct *newsksec = newsk->sk_security;
4316
4317         newsksec->sid = sksec->sid;
4318         newsksec->peer_sid = sksec->peer_sid;
4319         newsksec->sclass = sksec->sclass;
4320
4321         selinux_netlbl_sk_security_reset(newsksec);
4322 }
4323
4324 static void selinux_sk_getsecid(struct sock *sk, u32 *secid)
4325 {
4326         if (!sk)
4327                 *secid = SECINITSID_ANY_SOCKET;
4328         else {
4329                 struct sk_security_struct *sksec = sk->sk_security;
4330
4331                 *secid = sksec->sid;
4332         }
4333 }
4334
4335 static void selinux_sock_graft(struct sock *sk, struct socket *parent)
4336 {
4337         struct inode_security_struct *isec = SOCK_INODE(parent)->i_security;
4338         struct sk_security_struct *sksec = sk->sk_security;
4339
4340         if (sk->sk_family == PF_INET || sk->sk_family == PF_INET6 ||
4341             sk->sk_family == PF_UNIX)
4342                 isec->sid = sksec->sid;
4343         sksec->sclass = isec->sclass;
4344 }
4345
4346 static int selinux_inet_conn_request(struct sock *sk, struct sk_buff *skb,
4347                                      struct request_sock *req)
4348 {
4349         struct sk_security_struct *sksec = sk->sk_security;
4350         int err;
4351         u16 family = sk->sk_family;
4352         u32 newsid;
4353         u32 peersid;
4354
4355         /* handle mapped IPv4 packets arriving via IPv6 sockets */
4356         if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
4357                 family = PF_INET;
4358
4359         err = selinux_skb_peerlbl_sid(skb, family, &peersid);
4360         if (err)
4361                 return err;
4362         if (peersid == SECSID_NULL) {
4363                 req->secid = sksec->sid;
4364                 req->peer_secid = SECSID_NULL;
4365         } else {
4366                 err = security_sid_mls_copy(sksec->sid, peersid, &newsid);
4367                 if (err)
4368                         return err;
4369                 req->secid = newsid;
4370                 req->peer_secid = peersid;
4371         }
4372
4373         return selinux_netlbl_inet_conn_request(req, family);
4374 }
4375
4376 static void selinux_inet_csk_clone(struct sock *newsk,
4377                                    const struct request_sock *req)
4378 {
4379         struct sk_security_struct *newsksec = newsk->sk_security;
4380
4381         newsksec->sid = req->secid;
4382         newsksec->peer_sid = req->peer_secid;
4383         /* NOTE: Ideally, we should also get the isec->sid for the
4384            new socket in sync, but we don't have the isec available yet.
4385            So we will wait until sock_graft to do it, by which
4386            time it will have been created and available. */
4387
4388         /* We don't need to take any sort of lock here as we are the only
4389          * thread with access to newsksec */
4390         selinux_netlbl_inet_csk_clone(newsk, req->rsk_ops->family);
4391 }
4392
4393 static void selinux_inet_conn_established(struct sock *sk, struct sk_buff *skb)
4394 {
4395         u16 family = sk->sk_family;
4396         struct sk_security_struct *sksec = sk->sk_security;
4397
4398         /* handle mapped IPv4 packets arriving via IPv6 sockets */
4399         if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
4400                 family = PF_INET;
4401
4402         selinux_skb_peerlbl_sid(skb, family, &sksec->peer_sid);
4403 }
4404
4405 static int selinux_secmark_relabel_packet(u32 sid)
4406 {
4407         const struct task_security_struct *__tsec;
4408         u32 tsid;
4409
4410         __tsec = current_security();
4411         tsid = __tsec->sid;
4412
4413         return avc_has_perm(tsid, sid, SECCLASS_PACKET, PACKET__RELABELTO, NULL);
4414 }
4415
4416 static void selinux_secmark_refcount_inc(void)
4417 {
4418         atomic_inc(&selinux_secmark_refcount);
4419 }
4420
4421 static void selinux_secmark_refcount_dec(void)
4422 {
4423         atomic_dec(&selinux_secmark_refcount);
4424 }
4425
4426 static void selinux_req_classify_flow(const struct request_sock *req,
4427                                       struct flowi *fl)
4428 {
4429         fl->flowi_secid = req->secid;
4430 }
4431
4432 static int selinux_tun_dev_create(void)
4433 {
4434         u32 sid = current_sid();
4435
4436         /* we aren't taking into account the "sockcreate" SID since the socket
4437          * that is being created here is not a socket in the traditional sense,
4438          * instead it is a private sock, accessible only to the kernel, and
4439          * representing a wide range of network traffic spanning multiple
4440          * connections unlike traditional sockets - check the TUN driver to
4441          * get a better understanding of why this socket is special */
4442
4443         return avc_has_perm(sid, sid, SECCLASS_TUN_SOCKET, TUN_SOCKET__CREATE,
4444                             NULL);
4445 }
4446
4447 static void selinux_tun_dev_post_create(struct sock *sk)
4448 {
4449         struct sk_security_struct *sksec = sk->sk_security;
4450
4451         /* we don't currently perform any NetLabel based labeling here and it
4452          * isn't clear that we would want to do so anyway; while we could apply
4453          * labeling without the support of the TUN user the resulting labeled
4454          * traffic from the other end of the connection would almost certainly
4455          * cause confusion to the TUN user that had no idea network labeling
4456          * protocols were being used */
4457
4458         /* see the comments in selinux_tun_dev_create() about why we don't use
4459          * the sockcreate SID here */
4460
4461         sksec->sid = current_sid();
4462         sksec->sclass = SECCLASS_TUN_SOCKET;
4463 }
4464
4465 static int selinux_tun_dev_attach(struct sock *sk)
4466 {
4467         struct sk_security_struct *sksec = sk->sk_security;
4468         u32 sid = current_sid();
4469         int err;
4470
4471         err = avc_has_perm(sid, sksec->sid, SECCLASS_TUN_SOCKET,
4472                            TUN_SOCKET__RELABELFROM, NULL);
4473         if (err)
4474                 return err;
4475         err = avc_has_perm(sid, sid, SECCLASS_TUN_SOCKET,
4476                            TUN_SOCKET__RELABELTO, NULL);
4477         if (err)
4478                 return err;
4479
4480         sksec->sid = sid;
4481
4482         return 0;
4483 }
4484
4485 static int selinux_nlmsg_perm(struct sock *sk, struct sk_buff *skb)
4486 {
4487         int err = 0;
4488         u32 perm;
4489         struct nlmsghdr *nlh;
4490         struct sk_security_struct *sksec = sk->sk_security;
4491
4492         if (skb->len < NLMSG_SPACE(0)) {
4493                 err = -EINVAL;
4494                 goto out;
4495         }
4496         nlh = nlmsg_hdr(skb);
4497
4498         err = selinux_nlmsg_lookup(sksec->sclass, nlh->nlmsg_type, &perm);
4499         if (err) {
4500                 if (err == -EINVAL) {
4501                         audit_log(current->audit_context, GFP_KERNEL, AUDIT_SELINUX_ERR,
4502                                   "SELinux:  unrecognized netlink message"
4503                                   " type=%hu for sclass=%hu\n",
4504                                   nlh->nlmsg_type, sksec->sclass);
4505                         if (!selinux_enforcing || security_get_allow_unknown())
4506                                 err = 0;
4507                 }
4508
4509                 /* Ignore */
4510                 if (err == -ENOENT)
4511                         err = 0;
4512                 goto out;
4513         }
4514
4515         err = sock_has_perm(current, sk, perm);
4516 out:
4517         return err;
4518 }
4519
4520 #ifdef CONFIG_NETFILTER
4521
4522 static unsigned int selinux_ip_forward(struct sk_buff *skb, int ifindex,
4523                                        u16 family)
4524 {
4525         int err;
4526         char *addrp;
4527         u32 peer_sid;
4528         struct common_audit_data ad;
4529         struct lsm_network_audit net = {0,};
4530         u8 secmark_active;
4531         u8 netlbl_active;
4532         u8 peerlbl_active;
4533
4534         if (!selinux_policycap_netpeer)
4535                 return NF_ACCEPT;
4536
4537         secmark_active = selinux_secmark_enabled();
4538         netlbl_active = netlbl_enabled();
4539         peerlbl_active = netlbl_active || selinux_xfrm_enabled();
4540         if (!secmark_active && !peerlbl_active)
4541                 return NF_ACCEPT;
4542
4543         if (selinux_skb_peerlbl_sid(skb, family, &peer_sid) != 0)
4544                 return NF_DROP;
4545
4546         ad.type = LSM_AUDIT_DATA_NET;
4547         ad.u.net = &net;
4548         ad.u.net->netif = ifindex;
4549         ad.u.net->family = family;
4550         if (selinux_parse_skb(skb, &ad, &addrp, 1, NULL) != 0)
4551                 return NF_DROP;
4552
4553         if (peerlbl_active) {
4554                 err = selinux_inet_sys_rcv_skb(ifindex, addrp, family,
4555                                                peer_sid, &ad);
4556                 if (err) {
4557                         selinux_netlbl_err(skb, err, 1);
4558                         return NF_DROP;
4559                 }
4560         }
4561
4562         if (secmark_active)
4563                 if (avc_has_perm(peer_sid, skb->secmark,
4564                                  SECCLASS_PACKET, PACKET__FORWARD_IN, &ad))
4565                         return NF_DROP;
4566
4567         if (netlbl_active)
4568                 /* we do this in the FORWARD path and not the POST_ROUTING
4569                  * path because we want to make sure we apply the necessary
4570                  * labeling before IPsec is applied so we can leverage AH
4571                  * protection */
4572                 if (selinux_netlbl_skbuff_setsid(skb, family, peer_sid) != 0)
4573                         return NF_DROP;
4574
4575         return NF_ACCEPT;
4576 }
4577
4578 static unsigned int selinux_ipv4_forward(unsigned int hooknum,
4579                                          struct sk_buff *skb,
4580                                          const struct net_device *in,
4581                                          const struct net_device *out,
4582                                          int (*okfn)(struct sk_buff *))
4583 {
4584         return selinux_ip_forward(skb, in->ifindex, PF_INET);
4585 }
4586
4587 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
4588 static unsigned int selinux_ipv6_forward(unsigned int hooknum,
4589                                          struct sk_buff *skb,
4590                                          const struct net_device *in,
4591                                          const struct net_device *out,
4592                                          int (*okfn)(struct sk_buff *))
4593 {
4594         return selinux_ip_forward(skb, in->ifindex, PF_INET6);
4595 }
4596 #endif  /* IPV6 */
4597
4598 static unsigned int selinux_ip_output(struct sk_buff *skb,
4599                                       u16 family)
4600 {
4601         u32 sid;
4602
4603         if (!netlbl_enabled())
4604                 return NF_ACCEPT;
4605
4606         /* we do this in the LOCAL_OUT path and not the POST_ROUTING path
4607          * because we want to make sure we apply the necessary labeling
4608          * before IPsec is applied so we can leverage AH protection */
4609         if (skb->sk) {
4610                 struct sk_security_struct *sksec = skb->sk->sk_security;
4611                 sid = sksec->sid;
4612         } else
4613                 sid = SECINITSID_KERNEL;
4614         if (selinux_netlbl_skbuff_setsid(skb, family, sid) != 0)
4615                 return NF_DROP;
4616
4617         return NF_ACCEPT;
4618 }
4619
4620 static unsigned int selinux_ipv4_output(unsigned int hooknum,
4621                                         struct sk_buff *skb,
4622                                         const struct net_device *in,
4623                                         const struct net_device *out,
4624                                         int (*okfn)(struct sk_buff *))
4625 {
4626         return selinux_ip_output(skb, PF_INET);
4627 }
4628
4629 static unsigned int selinux_ip_postroute_compat(struct sk_buff *skb,
4630                                                 int ifindex,
4631                                                 u16 family)
4632 {
4633         struct sock *sk = skb->sk;
4634         struct sk_security_struct *sksec;
4635         struct common_audit_data ad;
4636         struct lsm_network_audit net = {0,};
4637         char *addrp;
4638         u8 proto;
4639
4640         if (sk == NULL)
4641                 return NF_ACCEPT;
4642         sksec = sk->sk_security;
4643
4644         ad.type = LSM_AUDIT_DATA_NET;
4645         ad.u.net = &net;
4646         ad.u.net->netif = ifindex;
4647         ad.u.net->family = family;
4648         if (selinux_parse_skb(skb, &ad, &addrp, 0, &proto))
4649                 return NF_DROP;
4650
4651         if (selinux_secmark_enabled())
4652                 if (avc_has_perm(sksec->sid, skb->secmark,
4653                                  SECCLASS_PACKET, PACKET__SEND, &ad))
4654                         return NF_DROP_ERR(-ECONNREFUSED);
4655
4656         if (selinux_xfrm_postroute_last(sksec->sid, skb, &ad, proto))
4657                 return NF_DROP_ERR(-ECONNREFUSED);
4658
4659         return NF_ACCEPT;
4660 }
4661
4662 static unsigned int selinux_ip_postroute(struct sk_buff *skb, int ifindex,
4663                                          u16 family)
4664 {
4665         u32 secmark_perm;
4666         u32 peer_sid;
4667         struct sock *sk;
4668         struct common_audit_data ad;
4669         struct lsm_network_audit net = {0,};
4670         char *addrp;
4671         u8 secmark_active;
4672         u8 peerlbl_active;
4673
4674         /* If any sort of compatibility mode is enabled then handoff processing
4675          * to the selinux_ip_postroute_compat() function to deal with the
4676          * special handling.  We do this in an attempt to keep this function
4677          * as fast and as clean as possible. */
4678         if (!selinux_policycap_netpeer)
4679                 return selinux_ip_postroute_compat(skb, ifindex, family);
4680 #ifdef CONFIG_XFRM
4681         /* If skb->dst->xfrm is non-NULL then the packet is undergoing an IPsec
4682          * packet transformation so allow the packet to pass without any checks
4683          * since we'll have another chance to perform access control checks
4684          * when the packet is on it's final way out.
4685          * NOTE: there appear to be some IPv6 multicast cases where skb->dst
4686          *       is NULL, in this case go ahead and apply access control. */
4687         if (skb_dst(skb) != NULL && skb_dst(skb)->xfrm != NULL)
4688                 return NF_ACCEPT;
4689 #endif
4690         secmark_active = selinux_secmark_enabled();
4691         peerlbl_active = netlbl_enabled() || selinux_xfrm_enabled();
4692         if (!secmark_active && !peerlbl_active)
4693                 return NF_ACCEPT;
4694
4695         /* if the packet is being forwarded then get the peer label from the
4696          * packet itself; otherwise check to see if it is from a local
4697          * application or the kernel, if from an application get the peer label
4698          * from the sending socket, otherwise use the kernel's sid */
4699         sk = skb->sk;
4700         if (sk == NULL) {
4701                 if (skb->skb_iif) {
4702                         secmark_perm = PACKET__FORWARD_OUT;
4703                         if (selinux_skb_peerlbl_sid(skb, family, &peer_sid))
4704                                 return NF_DROP;
4705                 } else {
4706                         secmark_perm = PACKET__SEND;
4707                         peer_sid = SECINITSID_KERNEL;
4708                 }
4709         } else {
4710                 struct sk_security_struct *sksec = sk->sk_security;
4711                 peer_sid = sksec->sid;
4712                 secmark_perm = PACKET__SEND;
4713         }
4714
4715         ad.type = LSM_AUDIT_DATA_NET;
4716         ad.u.net = &net;
4717         ad.u.net->netif = ifindex;
4718         ad.u.net->family = family;
4719         if (selinux_parse_skb(skb, &ad, &addrp, 0, NULL))
4720                 return NF_DROP;
4721
4722         if (secmark_active)
4723                 if (avc_has_perm(peer_sid, skb->secmark,
4724                                  SECCLASS_PACKET, secmark_perm, &ad))
4725                         return NF_DROP_ERR(-ECONNREFUSED);
4726
4727         if (peerlbl_active) {
4728                 u32 if_sid;
4729                 u32 node_sid;
4730
4731                 if (sel_netif_sid(ifindex, &if_sid))
4732                         return NF_DROP;
4733                 if (avc_has_perm(peer_sid, if_sid,
4734                                  SECCLASS_NETIF, NETIF__EGRESS, &ad))
4735                         return NF_DROP_ERR(-ECONNREFUSED);
4736
4737                 if (sel_netnode_sid(addrp, family, &node_sid))
4738                         return NF_DROP;
4739                 if (avc_has_perm(peer_sid, node_sid,
4740                                  SECCLASS_NODE, NODE__SENDTO, &ad))
4741                         return NF_DROP_ERR(-ECONNREFUSED);
4742         }
4743
4744         return NF_ACCEPT;
4745 }
4746
4747 static unsigned int selinux_ipv4_postroute(unsigned int hooknum,
4748                                            struct sk_buff *skb,
4749                                            const struct net_device *in,
4750                                            const struct net_device *out,
4751                                            int (*okfn)(struct sk_buff *))
4752 {
4753         return selinux_ip_postroute(skb, out->ifindex, PF_INET);
4754 }
4755
4756 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
4757 static unsigned int selinux_ipv6_postroute(unsigned int hooknum,
4758                                            struct sk_buff *skb,
4759                                            const struct net_device *in,
4760                                            const struct net_device *out,
4761                                            int (*okfn)(struct sk_buff *))
4762 {
4763         return selinux_ip_postroute(skb, out->ifindex, PF_INET6);
4764 }
4765 #endif  /* IPV6 */
4766
4767 #endif  /* CONFIG_NETFILTER */
4768
4769 static int selinux_netlink_send(struct sock *sk, struct sk_buff *skb)
4770 {
4771         int err;
4772
4773         err = cap_netlink_send(sk, skb);
4774         if (err)
4775                 return err;
4776
4777         return selinux_nlmsg_perm(sk, skb);
4778 }
4779
4780 static int ipc_alloc_security(struct task_struct *task,
4781                               struct kern_ipc_perm *perm,
4782                               u16 sclass)
4783 {
4784         struct ipc_security_struct *isec;
4785         u32 sid;
4786
4787         isec = kzalloc(sizeof(struct ipc_security_struct), GFP_KERNEL);
4788         if (!isec)
4789                 return -ENOMEM;
4790
4791         sid = task_sid(task);
4792         isec->sclass = sclass;
4793         isec->sid = sid;
4794         perm->security = isec;
4795
4796         return 0;
4797 }
4798
4799 static void ipc_free_security(struct kern_ipc_perm *perm)
4800 {
4801         struct ipc_security_struct *isec = perm->security;
4802         perm->security = NULL;
4803         kfree(isec);
4804 }
4805
4806 static int msg_msg_alloc_security(struct msg_msg *msg)
4807 {
4808         struct msg_security_struct *msec;
4809
4810         msec = kzalloc(sizeof(struct msg_security_struct), GFP_KERNEL);
4811         if (!msec)
4812                 return -ENOMEM;
4813
4814         msec->sid = SECINITSID_UNLABELED;
4815         msg->security = msec;
4816
4817         return 0;
4818 }
4819
4820 static void msg_msg_free_security(struct msg_msg *msg)
4821 {
4822         struct msg_security_struct *msec = msg->security;
4823
4824         msg->security = NULL;
4825         kfree(msec);
4826 }
4827
4828 static int ipc_has_perm(struct kern_ipc_perm *ipc_perms,
4829                         u32 perms)
4830 {
4831         struct ipc_security_struct *isec;
4832         struct common_audit_data ad;
4833         u32 sid = current_sid();
4834
4835         isec = ipc_perms->security;
4836
4837         ad.type = LSM_AUDIT_DATA_IPC;
4838         ad.u.ipc_id = ipc_perms->key;
4839
4840         return avc_has_perm(sid, isec->sid, isec->sclass, perms, &ad);
4841 }
4842
4843 static int selinux_msg_msg_alloc_security(struct msg_msg *msg)
4844 {
4845         return msg_msg_alloc_security(msg);
4846 }
4847
4848 static void selinux_msg_msg_free_security(struct msg_msg *msg)
4849 {
4850         msg_msg_free_security(msg);
4851 }
4852
4853 /* message queue security operations */
4854 static int selinux_msg_queue_alloc_security(struct msg_queue *msq)
4855 {
4856         struct ipc_security_struct *isec;
4857         struct common_audit_data ad;
4858         u32 sid = current_sid();
4859         int rc;
4860
4861         rc = ipc_alloc_security(current, &msq->q_perm, SECCLASS_MSGQ);
4862         if (rc)
4863                 return rc;
4864
4865         isec = msq->q_perm.security;
4866
4867         ad.type = LSM_AUDIT_DATA_IPC;
4868         ad.u.ipc_id = msq->q_perm.key;
4869
4870         rc = avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
4871                           MSGQ__CREATE, &ad);
4872         if (rc) {
4873                 ipc_free_security(&msq->q_perm);
4874                 return rc;
4875         }
4876         return 0;
4877 }
4878
4879 static void selinux_msg_queue_free_security(struct msg_queue *msq)
4880 {
4881         ipc_free_security(&msq->q_perm);
4882 }
4883
4884 static int selinux_msg_queue_associate(struct msg_queue *msq, int msqflg)
4885 {
4886         struct ipc_security_struct *isec;
4887         struct common_audit_data ad;
4888         u32 sid = current_sid();
4889
4890         isec = msq->q_perm.security;
4891
4892         ad.type = LSM_AUDIT_DATA_IPC;
4893         ad.u.ipc_id = msq->q_perm.key;
4894
4895         return avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
4896                             MSGQ__ASSOCIATE, &ad);
4897 }
4898
4899 static int selinux_msg_queue_msgctl(struct msg_queue *msq, int cmd)
4900 {
4901         int err;
4902         int perms;
4903
4904         switch (cmd) {
4905         case IPC_INFO:
4906         case MSG_INFO:
4907                 /* No specific object, just general system-wide information. */
4908                 return task_has_system(current, SYSTEM__IPC_INFO);
4909         case IPC_STAT:
4910         case MSG_STAT:
4911                 perms = MSGQ__GETATTR | MSGQ__ASSOCIATE;
4912                 break;
4913         case IPC_SET:
4914                 perms = MSGQ__SETATTR;
4915                 break;
4916         case IPC_RMID:
4917                 perms = MSGQ__DESTROY;
4918                 break;
4919         default:
4920                 return 0;
4921         }
4922
4923         err = ipc_has_perm(&msq->q_perm, perms);
4924         return err;
4925 }
4926
4927 static int selinux_msg_queue_msgsnd(struct msg_queue *msq, struct msg_msg *msg, int msqflg)
4928 {
4929         struct ipc_security_struct *isec;
4930         struct msg_security_struct *msec;
4931         struct common_audit_data ad;
4932         u32 sid = current_sid();
4933         int rc;
4934
4935         isec = msq->q_perm.security;
4936         msec = msg->security;
4937
4938         /*
4939          * First time through, need to assign label to the message
4940          */
4941         if (msec->sid == SECINITSID_UNLABELED) {
4942                 /*
4943                  * Compute new sid based on current process and
4944                  * message queue this message will be stored in
4945                  */
4946                 rc = security_transition_sid(sid, isec->sid, SECCLASS_MSG,
4947                                              NULL, &msec->sid);
4948                 if (rc)
4949                         return rc;
4950         }
4951
4952         ad.type = LSM_AUDIT_DATA_IPC;
4953         ad.u.ipc_id = msq->q_perm.key;
4954
4955         /* Can this process write to the queue? */
4956         rc = avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
4957                           MSGQ__WRITE, &ad);
4958         if (!rc)
4959                 /* Can this process send the message */
4960                 rc = avc_has_perm(sid, msec->sid, SECCLASS_MSG,
4961                                   MSG__SEND, &ad);
4962         if (!rc)
4963                 /* Can the message be put in the queue? */
4964                 rc = avc_has_perm(msec->sid, isec->sid, SECCLASS_MSGQ,
4965                                   MSGQ__ENQUEUE, &ad);
4966
4967         return rc;
4968 }
4969
4970 static int selinux_msg_queue_msgrcv(struct msg_queue *msq, struct msg_msg *msg,
4971                                     struct task_struct *target,
4972                                     long type, int mode)
4973 {
4974         struct ipc_security_struct *isec;
4975         struct msg_security_struct *msec;
4976         struct common_audit_data ad;
4977         u32 sid = task_sid(target);
4978         int rc;
4979
4980         isec = msq->q_perm.security;
4981         msec = msg->security;
4982
4983         ad.type = LSM_AUDIT_DATA_IPC;
4984         ad.u.ipc_id = msq->q_perm.key;
4985
4986         rc = avc_has_perm(sid, isec->sid,
4987                           SECCLASS_MSGQ, MSGQ__READ, &ad);
4988         if (!rc)
4989                 rc = avc_has_perm(sid, msec->sid,
4990                                   SECCLASS_MSG, MSG__RECEIVE, &ad);
4991         return rc;
4992 }
4993
4994 /* Shared Memory security operations */
4995 static int selinux_shm_alloc_security(struct shmid_kernel *shp)
4996 {
4997         struct ipc_security_struct *isec;
4998         struct common_audit_data ad;
4999         u32 sid = current_sid();
5000         int rc;
5001
5002         rc = ipc_alloc_security(current, &shp->shm_perm, SECCLASS_SHM);
5003         if (rc)
5004                 return rc;
5005
5006         isec = shp->shm_perm.security;
5007
5008         ad.type = LSM_AUDIT_DATA_IPC;
5009         ad.u.ipc_id = shp->shm_perm.key;
5010
5011         rc = avc_has_perm(sid, isec->sid, SECCLASS_SHM,
5012                           SHM__CREATE, &ad);
5013         if (rc) {
5014                 ipc_free_security(&shp->shm_perm);
5015                 return rc;
5016         }
5017         return 0;
5018 }
5019
5020 static void selinux_shm_free_security(struct shmid_kernel *shp)
5021 {
5022         ipc_free_security(&shp->shm_perm);
5023 }
5024
5025 static int selinux_shm_associate(struct shmid_kernel *shp, int shmflg)
5026 {
5027         struct ipc_security_struct *isec;
5028         struct common_audit_data ad;
5029         u32 sid = current_sid();
5030
5031         isec = shp->shm_perm.security;
5032
5033         ad.type = LSM_AUDIT_DATA_IPC;
5034         ad.u.ipc_id = shp->shm_perm.key;
5035
5036         return avc_has_perm(sid, isec->sid, SECCLASS_SHM,
5037                             SHM__ASSOCIATE, &ad);
5038 }
5039
5040 /* Note, at this point, shp is locked down */
5041 static int selinux_shm_shmctl(struct shmid_kernel *shp, int cmd)
5042 {
5043         int perms;
5044         int err;
5045
5046         switch (cmd) {
5047         case IPC_INFO:
5048         case SHM_INFO:
5049                 /* No specific object, just general system-wide information. */
5050                 return task_has_system(current, SYSTEM__IPC_INFO);
5051         case IPC_STAT:
5052         case SHM_STAT:
5053                 perms = SHM__GETATTR | SHM__ASSOCIATE;
5054                 break;
5055         case IPC_SET:
5056                 perms = SHM__SETATTR;
5057                 break;
5058         case SHM_LOCK:
5059         case SHM_UNLOCK:
5060                 perms = SHM__LOCK;
5061                 break;
5062         case IPC_RMID:
5063                 perms = SHM__DESTROY;
5064                 break;
5065         default:
5066                 return 0;
5067         }
5068
5069         err = ipc_has_perm(&shp->shm_perm, perms);
5070         return err;
5071 }
5072
5073 static int selinux_shm_shmat(struct shmid_kernel *shp,
5074                              char __user *shmaddr, int shmflg)
5075 {
5076         u32 perms;
5077
5078         if (shmflg & SHM_RDONLY)
5079                 perms = SHM__READ;
5080         else
5081                 perms = SHM__READ | SHM__WRITE;
5082
5083         return ipc_has_perm(&shp->shm_perm, perms);
5084 }
5085
5086 /* Semaphore security operations */
5087 static int selinux_sem_alloc_security(struct sem_array *sma)
5088 {
5089         struct ipc_security_struct *isec;
5090         struct common_audit_data ad;
5091         u32 sid = current_sid();
5092         int rc;
5093
5094         rc = ipc_alloc_security(current, &sma->sem_perm, SECCLASS_SEM);
5095         if (rc)
5096                 return rc;
5097
5098         isec = sma->sem_perm.security;
5099
5100         ad.type = LSM_AUDIT_DATA_IPC;
5101         ad.u.ipc_id = sma->sem_perm.key;
5102
5103         rc = avc_has_perm(sid, isec->sid, SECCLASS_SEM,
5104                           SEM__CREATE, &ad);
5105         if (rc) {
5106                 ipc_free_security(&sma->sem_perm);
5107                 return rc;
5108         }
5109         return 0;
5110 }
5111
5112 static void selinux_sem_free_security(struct sem_array *sma)
5113 {
5114         ipc_free_security(&sma->sem_perm);
5115 }
5116
5117 static int selinux_sem_associate(struct sem_array *sma, int semflg)
5118 {
5119         struct ipc_security_struct *isec;
5120         struct common_audit_data ad;
5121         u32 sid = current_sid();
5122
5123         isec = sma->sem_perm.security;
5124
5125         ad.type = LSM_AUDIT_DATA_IPC;
5126         ad.u.ipc_id = sma->sem_perm.key;
5127
5128         return avc_has_perm(sid, isec->sid, SECCLASS_SEM,
5129                             SEM__ASSOCIATE, &ad);
5130 }
5131
5132 /* Note, at this point, sma is locked down */
5133 static int selinux_sem_semctl(struct sem_array *sma, int cmd)
5134 {
5135         int err;
5136         u32 perms;
5137
5138         switch (cmd) {
5139         case IPC_INFO:
5140         case SEM_INFO:
5141                 /* No specific object, just general system-wide information. */
5142                 return task_has_system(current, SYSTEM__IPC_INFO);
5143         case GETPID:
5144         case GETNCNT:
5145         case GETZCNT:
5146                 perms = SEM__GETATTR;
5147                 break;
5148         case GETVAL:
5149         case GETALL:
5150                 perms = SEM__READ;
5151                 break;
5152         case SETVAL:
5153         case SETALL:
5154                 perms = SEM__WRITE;
5155                 break;
5156         case IPC_RMID:
5157                 perms = SEM__DESTROY;
5158                 break;
5159         case IPC_SET:
5160                 perms = SEM__SETATTR;
5161                 break;
5162         case IPC_STAT:
5163         case SEM_STAT:
5164                 perms = SEM__GETATTR | SEM__ASSOCIATE;
5165                 break;
5166         default:
5167                 return 0;
5168         }
5169
5170         err = ipc_has_perm(&sma->sem_perm, perms);
5171         return err;
5172 }
5173
5174 static int selinux_sem_semop(struct sem_array *sma,
5175                              struct sembuf *sops, unsigned nsops, int alter)
5176 {
5177         u32 perms;
5178
5179         if (alter)
5180                 perms = SEM__READ | SEM__WRITE;
5181         else
5182                 perms = SEM__READ;
5183
5184         return ipc_has_perm(&sma->sem_perm, perms);
5185 }
5186
5187 static int selinux_ipc_permission(struct kern_ipc_perm *ipcp, short flag)
5188 {
5189         u32 av = 0;
5190
5191         av = 0;
5192         if (flag & S_IRUGO)
5193                 av |= IPC__UNIX_READ;
5194         if (flag & S_IWUGO)
5195                 av |= IPC__UNIX_WRITE;
5196
5197         if (av == 0)
5198                 return 0;
5199
5200         return ipc_has_perm(ipcp, av);
5201 }
5202
5203 static void selinux_ipc_getsecid(struct kern_ipc_perm *ipcp, u32 *secid)
5204 {
5205         struct ipc_security_struct *isec = ipcp->security;
5206         *secid = isec->sid;
5207 }
5208
5209 static void selinux_d_instantiate(struct dentry *dentry, struct inode *inode)
5210 {
5211         if (inode)
5212                 inode_doinit_with_dentry(inode, dentry);
5213 }
5214
5215 static int selinux_getprocattr(struct task_struct *p,
5216                                char *name, char **value)
5217 {
5218         const struct task_security_struct *__tsec;
5219         u32 sid;
5220         int error;
5221         unsigned len;
5222
5223         if (current != p) {
5224                 error = current_has_perm(p, PROCESS__GETATTR);
5225                 if (error)
5226                         return error;
5227         }
5228
5229         rcu_read_lock();
5230         __tsec = __task_cred(p)->security;
5231
5232         if (!strcmp(name, "current"))
5233                 sid = __tsec->sid;
5234         else if (!strcmp(name, "prev"))
5235                 sid = __tsec->osid;
5236         else if (!strcmp(name, "exec"))
5237                 sid = __tsec->exec_sid;
5238         else if (!strcmp(name, "fscreate"))
5239                 sid = __tsec->create_sid;
5240         else if (!strcmp(name, "keycreate"))
5241                 sid = __tsec->keycreate_sid;
5242         else if (!strcmp(name, "sockcreate"))
5243                 sid = __tsec->sockcreate_sid;
5244         else
5245                 goto invalid;
5246         rcu_read_unlock();
5247
5248         if (!sid)
5249                 return 0;
5250
5251         error = security_sid_to_context(sid, value, &len);
5252         if (error)
5253                 return error;
5254         return len;
5255
5256 invalid:
5257         rcu_read_unlock();
5258         return -EINVAL;
5259 }
5260
5261 static int selinux_setprocattr(struct task_struct *p,
5262                                char *name, void *value, size_t size)
5263 {
5264         struct task_security_struct *tsec;
5265         struct task_struct *tracer;
5266         struct cred *new;
5267         u32 sid = 0, ptsid;
5268         int error;
5269         char *str = value;
5270
5271         if (current != p) {
5272                 /* SELinux only allows a process to change its own
5273                    security attributes. */
5274                 return -EACCES;
5275         }
5276
5277         /*
5278          * Basic control over ability to set these attributes at all.
5279          * current == p, but we'll pass them separately in case the
5280          * above restriction is ever removed.
5281          */
5282         if (!strcmp(name, "exec"))
5283                 error = current_has_perm(p, PROCESS__SETEXEC);
5284         else if (!strcmp(name, "fscreate"))
5285                 error = current_has_perm(p, PROCESS__SETFSCREATE);
5286         else if (!strcmp(name, "keycreate"))
5287                 error = current_has_perm(p, PROCESS__SETKEYCREATE);
5288         else if (!strcmp(name, "sockcreate"))
5289                 error = current_has_perm(p, PROCESS__SETSOCKCREATE);
5290         else if (!strcmp(name, "current"))
5291                 error = current_has_perm(p, PROCESS__SETCURRENT);
5292         else
5293                 error = -EINVAL;
5294         if (error)
5295                 return error;
5296
5297         /* Obtain a SID for the context, if one was specified. */
5298         if (size && str[1] && str[1] != '\n') {
5299                 if (str[size-1] == '\n') {
5300                         str[size-1] = 0;
5301                         size--;
5302                 }
5303                 error = security_context_to_sid(value, size, &sid);
5304                 if (error == -EINVAL && !strcmp(name, "fscreate")) {
5305                         if (!capable(CAP_MAC_ADMIN)) {
5306                                 struct audit_buffer *ab;
5307                                 size_t audit_size;
5308
5309                                 /* We strip a nul only if it is at the end, otherwise the
5310                                  * context contains a nul and we should audit that */
5311                                 if (str[size - 1] == '\0')
5312                                         audit_size = size - 1;
5313                                 else
5314                                         audit_size = size;
5315                                 ab = audit_log_start(current->audit_context, GFP_ATOMIC, AUDIT_SELINUX_ERR);
5316                                 audit_log_format(ab, "op=fscreate invalid_context=");
5317                                 audit_log_n_untrustedstring(ab, value, audit_size);
5318                                 audit_log_end(ab);
5319
5320                                 return error;
5321                         }
5322                         error = security_context_to_sid_force(value, size,
5323                                                               &sid);
5324                 }
5325                 if (error)
5326                         return error;
5327         }
5328
5329         new = prepare_creds();
5330         if (!new)
5331                 return -ENOMEM;
5332
5333         /* Permission checking based on the specified context is
5334            performed during the actual operation (execve,
5335            open/mkdir/...), when we know the full context of the
5336            operation.  See selinux_bprm_set_creds for the execve
5337            checks and may_create for the file creation checks. The
5338            operation will then fail if the context is not permitted. */
5339         tsec = new->security;
5340         if (!strcmp(name, "exec")) {
5341                 tsec->exec_sid = sid;
5342         } else if (!strcmp(name, "fscreate")) {
5343                 tsec->create_sid = sid;
5344         } else if (!strcmp(name, "keycreate")) {
5345                 error = may_create_key(sid, p);
5346                 if (error)
5347                         goto abort_change;
5348                 tsec->keycreate_sid = sid;
5349         } else if (!strcmp(name, "sockcreate")) {
5350                 tsec->sockcreate_sid = sid;
5351         } else if (!strcmp(name, "current")) {
5352                 error = -EINVAL;
5353                 if (sid == 0)
5354                         goto abort_change;
5355
5356                 /* Only allow single threaded processes to change context */
5357                 error = -EPERM;
5358                 if (!current_is_single_threaded()) {
5359                         error = security_bounded_transition(tsec->sid, sid);
5360                         if (error)
5361                                 goto abort_change;
5362                 }
5363
5364                 /* Check permissions for the transition. */
5365                 error = avc_has_perm(tsec->sid, sid, SECCLASS_PROCESS,
5366                                      PROCESS__DYNTRANSITION, NULL);
5367                 if (error)
5368                         goto abort_change;
5369
5370                 /* Check for ptracing, and update the task SID if ok.
5371                    Otherwise, leave SID unchanged and fail. */
5372                 ptsid = 0;
5373                 task_lock(p);
5374                 tracer = ptrace_parent(p);
5375                 if (tracer)
5376                         ptsid = task_sid(tracer);
5377                 task_unlock(p);
5378
5379                 if (tracer) {
5380                         error = avc_has_perm(ptsid, sid, SECCLASS_PROCESS,
5381                                              PROCESS__PTRACE, NULL);
5382                         if (error)
5383                                 goto abort_change;
5384                 }
5385
5386                 tsec->sid = sid;
5387         } else {
5388                 error = -EINVAL;
5389                 goto abort_change;
5390         }
5391
5392         commit_creds(new);
5393         return size;
5394
5395 abort_change:
5396         abort_creds(new);
5397         return error;
5398 }
5399
5400 static int selinux_secid_to_secctx(u32 secid, char **secdata, u32 *seclen)
5401 {
5402         return security_sid_to_context(secid, secdata, seclen);
5403 }
5404
5405 static int selinux_secctx_to_secid(const char *secdata, u32 seclen, u32 *secid)
5406 {
5407         return security_context_to_sid(secdata, seclen, secid);
5408 }
5409
5410 static void selinux_release_secctx(char *secdata, u32 seclen)
5411 {
5412         kfree(secdata);
5413 }
5414
5415 /*
5416  *      called with inode->i_mutex locked
5417  */
5418 static int selinux_inode_notifysecctx(struct inode *inode, void *ctx, u32 ctxlen)
5419 {
5420         return selinux_inode_setsecurity(inode, XATTR_SELINUX_SUFFIX, ctx, ctxlen, 0);
5421 }
5422
5423 /*
5424  *      called with inode->i_mutex locked
5425  */
5426 static int selinux_inode_setsecctx(struct dentry *dentry, void *ctx, u32 ctxlen)
5427 {
5428         return __vfs_setxattr_noperm(dentry, XATTR_NAME_SELINUX, ctx, ctxlen, 0);
5429 }
5430
5431 static int selinux_inode_getsecctx(struct inode *inode, void **ctx, u32 *ctxlen)
5432 {
5433         int len = 0;
5434         len = selinux_inode_getsecurity(inode, XATTR_SELINUX_SUFFIX,
5435                                                 ctx, true);
5436         if (len < 0)
5437                 return len;
5438         *ctxlen = len;
5439         return 0;
5440 }
5441 #ifdef CONFIG_KEYS
5442
5443 static int selinux_key_alloc(struct key *k, const struct cred *cred,
5444                              unsigned long flags)
5445 {
5446         const struct task_security_struct *tsec;
5447         struct key_security_struct *ksec;
5448
5449         ksec = kzalloc(sizeof(struct key_security_struct), GFP_KERNEL);
5450         if (!ksec)
5451                 return -ENOMEM;
5452
5453         tsec = cred->security;
5454         if (tsec->keycreate_sid)
5455                 ksec->sid = tsec->keycreate_sid;
5456         else
5457                 ksec->sid = tsec->sid;
5458
5459         k->security = ksec;
5460         return 0;
5461 }
5462
5463 static void selinux_key_free(struct key *k)
5464 {
5465         struct key_security_struct *ksec = k->security;
5466
5467         k->security = NULL;
5468         kfree(ksec);
5469 }
5470
5471 static int selinux_key_permission(key_ref_t key_ref,
5472                                   const struct cred *cred,
5473                                   key_perm_t perm)
5474 {
5475         struct key *key;
5476         struct key_security_struct *ksec;
5477         u32 sid;
5478
5479         /* if no specific permissions are requested, we skip the
5480            permission check. No serious, additional covert channels
5481            appear to be created. */
5482         if (perm == 0)
5483                 return 0;
5484
5485         sid = cred_sid(cred);
5486
5487         key = key_ref_to_ptr(key_ref);
5488         ksec = key->security;
5489
5490         return avc_has_perm(sid, ksec->sid, SECCLASS_KEY, perm, NULL);
5491 }
5492
5493 static int selinux_key_getsecurity(struct key *key, char **_buffer)
5494 {
5495         struct key_security_struct *ksec = key->security;
5496         char *context = NULL;
5497         unsigned len;
5498         int rc;
5499
5500         rc = security_sid_to_context(ksec->sid, &context, &len);
5501         if (!rc)
5502                 rc = len;
5503         *_buffer = context;
5504         return rc;
5505 }
5506
5507 #endif
5508
5509 static struct security_operations selinux_ops = {
5510         .name =                         "selinux",
5511
5512         .ptrace_access_check =          selinux_ptrace_access_check,
5513         .ptrace_traceme =               selinux_ptrace_traceme,
5514         .capget =                       selinux_capget,
5515         .capset =                       selinux_capset,
5516         .capable =                      selinux_capable,
5517         .quotactl =                     selinux_quotactl,
5518         .quota_on =                     selinux_quota_on,
5519         .syslog =                       selinux_syslog,
5520         .vm_enough_memory =             selinux_vm_enough_memory,
5521
5522         .netlink_send =                 selinux_netlink_send,
5523
5524         .bprm_set_creds =               selinux_bprm_set_creds,
5525         .bprm_committing_creds =        selinux_bprm_committing_creds,
5526         .bprm_committed_creds =         selinux_bprm_committed_creds,
5527         .bprm_secureexec =              selinux_bprm_secureexec,
5528
5529         .sb_alloc_security =            selinux_sb_alloc_security,
5530         .sb_free_security =             selinux_sb_free_security,
5531         .sb_copy_data =                 selinux_sb_copy_data,
5532         .sb_remount =                   selinux_sb_remount,
5533         .sb_kern_mount =                selinux_sb_kern_mount,
5534         .sb_show_options =              selinux_sb_show_options,
5535         .sb_statfs =                    selinux_sb_statfs,
5536         .sb_mount =                     selinux_mount,
5537         .sb_umount =                    selinux_umount,
5538         .sb_set_mnt_opts =              selinux_set_mnt_opts,
5539         .sb_clone_mnt_opts =            selinux_sb_clone_mnt_opts,
5540         .sb_parse_opts_str =            selinux_parse_opts_str,
5541
5542
5543         .inode_alloc_security =         selinux_inode_alloc_security,
5544         .inode_free_security =          selinux_inode_free_security,
5545         .inode_init_security =          selinux_inode_init_security,
5546         .inode_create =                 selinux_inode_create,
5547         .inode_link =                   selinux_inode_link,
5548         .inode_unlink =                 selinux_inode_unlink,
5549         .inode_symlink =                selinux_inode_symlink,
5550         .inode_mkdir =                  selinux_inode_mkdir,
5551         .inode_rmdir =                  selinux_inode_rmdir,
5552         .inode_mknod =                  selinux_inode_mknod,
5553         .inode_rename =                 selinux_inode_rename,
5554         .inode_readlink =               selinux_inode_readlink,
5555         .inode_follow_link =            selinux_inode_follow_link,
5556         .inode_permission =             selinux_inode_permission,
5557         .inode_setattr =                selinux_inode_setattr,
5558         .inode_getattr =                selinux_inode_getattr,
5559         .inode_setxattr =               selinux_inode_setxattr,
5560         .inode_post_setxattr =          selinux_inode_post_setxattr,
5561         .inode_getxattr =               selinux_inode_getxattr,
5562         .inode_listxattr =              selinux_inode_listxattr,
5563         .inode_removexattr =            selinux_inode_removexattr,
5564         .inode_getsecurity =            selinux_inode_getsecurity,
5565         .inode_setsecurity =            selinux_inode_setsecurity,
5566         .inode_listsecurity =           selinux_inode_listsecurity,
5567         .inode_getsecid =               selinux_inode_getsecid,
5568
5569         .file_permission =              selinux_file_permission,
5570         .file_alloc_security =          selinux_file_alloc_security,
5571         .file_free_security =           selinux_file_free_security,
5572         .file_ioctl =                   selinux_file_ioctl,
5573         .mmap_file =                    selinux_mmap_file,
5574         .mmap_addr =                    selinux_mmap_addr,
5575         .file_mprotect =                selinux_file_mprotect,
5576         .file_lock =                    selinux_file_lock,
5577         .file_fcntl =                   selinux_file_fcntl,
5578         .file_set_fowner =              selinux_file_set_fowner,
5579         .file_send_sigiotask =          selinux_file_send_sigiotask,
5580         .file_receive =                 selinux_file_receive,
5581
5582         .file_open =                    selinux_file_open,
5583
5584         .task_create =                  selinux_task_create,
5585         .cred_alloc_blank =             selinux_cred_alloc_blank,
5586         .cred_free =                    selinux_cred_free,
5587         .cred_prepare =                 selinux_cred_prepare,
5588         .cred_transfer =                selinux_cred_transfer,
5589         .kernel_act_as =                selinux_kernel_act_as,
5590         .kernel_create_files_as =       selinux_kernel_create_files_as,
5591         .kernel_module_request =        selinux_kernel_module_request,
5592         .task_setpgid =                 selinux_task_setpgid,
5593         .task_getpgid =                 selinux_task_getpgid,
5594         .task_getsid =                  selinux_task_getsid,
5595         .task_getsecid =                selinux_task_getsecid,
5596         .task_setnice =                 selinux_task_setnice,
5597         .task_setioprio =               selinux_task_setioprio,
5598         .task_getioprio =               selinux_task_getioprio,
5599         .task_setrlimit =               selinux_task_setrlimit,
5600         .task_setscheduler =            selinux_task_setscheduler,
5601         .task_getscheduler =            selinux_task_getscheduler,
5602         .task_movememory =              selinux_task_movememory,
5603         .task_kill =                    selinux_task_kill,
5604         .task_wait =                    selinux_task_wait,
5605         .task_to_inode =                selinux_task_to_inode,
5606
5607         .ipc_permission =               selinux_ipc_permission,
5608         .ipc_getsecid =                 selinux_ipc_getsecid,
5609
5610         .msg_msg_alloc_security =       selinux_msg_msg_alloc_security,
5611         .msg_msg_free_security =        selinux_msg_msg_free_security,
5612
5613         .msg_queue_alloc_security =     selinux_msg_queue_alloc_security,
5614         .msg_queue_free_security =      selinux_msg_queue_free_security,
5615         .msg_queue_associate =          selinux_msg_queue_associate,
5616         .msg_queue_msgctl =             selinux_msg_queue_msgctl,
5617         .msg_queue_msgsnd =             selinux_msg_queue_msgsnd,
5618         .msg_queue_msgrcv =             selinux_msg_queue_msgrcv,
5619
5620         .shm_alloc_security =           selinux_shm_alloc_security,
5621         .shm_free_security =            selinux_shm_free_security,
5622         .shm_associate =                selinux_shm_associate,
5623         .shm_shmctl =                   selinux_shm_shmctl,
5624         .shm_shmat =                    selinux_shm_shmat,
5625
5626         .sem_alloc_security =           selinux_sem_alloc_security,
5627         .sem_free_security =            selinux_sem_free_security,
5628         .sem_associate =                selinux_sem_associate,
5629         .sem_semctl =                   selinux_sem_semctl,
5630         .sem_semop =                    selinux_sem_semop,
5631
5632         .d_instantiate =                selinux_d_instantiate,
5633
5634         .getprocattr =                  selinux_getprocattr,
5635         .setprocattr =                  selinux_setprocattr,
5636
5637         .secid_to_secctx =              selinux_secid_to_secctx,
5638         .secctx_to_secid =              selinux_secctx_to_secid,
5639         .release_secctx =               selinux_release_secctx,
5640         .inode_notifysecctx =           selinux_inode_notifysecctx,
5641         .inode_setsecctx =              selinux_inode_setsecctx,
5642         .inode_getsecctx =              selinux_inode_getsecctx,
5643
5644         .unix_stream_connect =          selinux_socket_unix_stream_connect,
5645         .unix_may_send =                selinux_socket_unix_may_send,
5646
5647         .socket_create =                selinux_socket_create,
5648         .socket_post_create =           selinux_socket_post_create,
5649         .socket_bind =                  selinux_socket_bind,
5650         .socket_connect =               selinux_socket_connect,
5651         .socket_listen =                selinux_socket_listen,
5652         .socket_accept =                selinux_socket_accept,
5653         .socket_sendmsg =               selinux_socket_sendmsg,
5654         .socket_recvmsg =               selinux_socket_recvmsg,
5655         .socket_getsockname =           selinux_socket_getsockname,
5656         .socket_getpeername =           selinux_socket_getpeername,
5657         .socket_getsockopt =            selinux_socket_getsockopt,
5658         .socket_setsockopt =            selinux_socket_setsockopt,
5659         .socket_shutdown =              selinux_socket_shutdown,
5660         .socket_sock_rcv_skb =          selinux_socket_sock_rcv_skb,
5661         .socket_getpeersec_stream =     selinux_socket_getpeersec_stream,
5662         .socket_getpeersec_dgram =      selinux_socket_getpeersec_dgram,
5663         .sk_alloc_security =            selinux_sk_alloc_security,
5664         .sk_free_security =             selinux_sk_free_security,
5665         .sk_clone_security =            selinux_sk_clone_security,
5666         .sk_getsecid =                  selinux_sk_getsecid,
5667         .sock_graft =                   selinux_sock_graft,
5668         .inet_conn_request =            selinux_inet_conn_request,
5669         .inet_csk_clone =               selinux_inet_csk_clone,
5670         .inet_conn_established =        selinux_inet_conn_established,
5671         .secmark_relabel_packet =       selinux_secmark_relabel_packet,
5672         .secmark_refcount_inc =         selinux_secmark_refcount_inc,
5673         .secmark_refcount_dec =         selinux_secmark_refcount_dec,
5674         .req_classify_flow =            selinux_req_classify_flow,
5675         .tun_dev_create =               selinux_tun_dev_create,
5676         .tun_dev_post_create =          selinux_tun_dev_post_create,
5677         .tun_dev_attach =               selinux_tun_dev_attach,
5678
5679 #ifdef CONFIG_SECURITY_NETWORK_XFRM
5680         .xfrm_policy_alloc_security =   selinux_xfrm_policy_alloc,
5681         .xfrm_policy_clone_security =   selinux_xfrm_policy_clone,
5682         .xfrm_policy_free_security =    selinux_xfrm_policy_free,
5683         .xfrm_policy_delete_security =  selinux_xfrm_policy_delete,
5684         .xfrm_state_alloc_security =    selinux_xfrm_state_alloc,
5685         .xfrm_state_free_security =     selinux_xfrm_state_free,
5686         .xfrm_state_delete_security =   selinux_xfrm_state_delete,
5687         .xfrm_policy_lookup =           selinux_xfrm_policy_lookup,
5688         .xfrm_state_pol_flow_match =    selinux_xfrm_state_pol_flow_match,
5689         .xfrm_decode_session =          selinux_xfrm_decode_session,
5690 #endif
5691
5692 #ifdef CONFIG_KEYS
5693         .key_alloc =                    selinux_key_alloc,
5694         .key_free =                     selinux_key_free,
5695         .key_permission =               selinux_key_permission,
5696         .key_getsecurity =              selinux_key_getsecurity,
5697 #endif
5698
5699 #ifdef CONFIG_AUDIT
5700         .audit_rule_init =              selinux_audit_rule_init,
5701         .audit_rule_known =             selinux_audit_rule_known,
5702         .audit_rule_match =             selinux_audit_rule_match,
5703         .audit_rule_free =              selinux_audit_rule_free,
5704 #endif
5705 };
5706
5707 static __init int selinux_init(void)
5708 {
5709         if (!security_module_enable(&selinux_ops)) {
5710                 selinux_enabled = 0;
5711                 return 0;
5712         }
5713
5714         if (!selinux_enabled) {
5715                 printk(KERN_INFO "SELinux:  Disabled at boot.\n");
5716                 return 0;
5717         }
5718
5719         printk(KERN_INFO "SELinux:  Initializing.\n");
5720
5721         /* Set the security state for the initial task. */
5722         cred_init_security();
5723
5724         default_noexec = !(VM_DATA_DEFAULT_FLAGS & VM_EXEC);
5725
5726         sel_inode_cache = kmem_cache_create("selinux_inode_security",
5727                                             sizeof(struct inode_security_struct),
5728                                             0, SLAB_PANIC, NULL);
5729         avc_init();
5730
5731         if (register_security(&selinux_ops))
5732                 panic("SELinux: Unable to register with kernel.\n");
5733
5734         if (selinux_enforcing)
5735                 printk(KERN_DEBUG "SELinux:  Starting in enforcing mode\n");
5736         else
5737                 printk(KERN_DEBUG "SELinux:  Starting in permissive mode\n");
5738
5739         return 0;
5740 }
5741
5742 static void delayed_superblock_init(struct super_block *sb, void *unused)
5743 {
5744         superblock_doinit(sb, NULL);
5745 }
5746
5747 void selinux_complete_init(void)
5748 {
5749         printk(KERN_DEBUG "SELinux:  Completing initialization.\n");
5750
5751         /* Set up any superblocks initialized prior to the policy load. */
5752         printk(KERN_DEBUG "SELinux:  Setting up existing superblocks.\n");
5753         iterate_supers(delayed_superblock_init, NULL);
5754 }
5755
5756 /* SELinux requires early initialization in order to label
5757    all processes and objects when they are created. */
5758 security_initcall(selinux_init);
5759
5760 #if defined(CONFIG_NETFILTER)
5761
5762 static struct nf_hook_ops selinux_ipv4_ops[] = {
5763         {
5764                 .hook =         selinux_ipv4_postroute,
5765                 .owner =        THIS_MODULE,
5766                 .pf =           PF_INET,
5767                 .hooknum =      NF_INET_POST_ROUTING,
5768                 .priority =     NF_IP_PRI_SELINUX_LAST,
5769         },
5770         {
5771                 .hook =         selinux_ipv4_forward,
5772                 .owner =        THIS_MODULE,
5773                 .pf =           PF_INET,
5774                 .hooknum =      NF_INET_FORWARD,
5775                 .priority =     NF_IP_PRI_SELINUX_FIRST,
5776         },
5777         {
5778                 .hook =         selinux_ipv4_output,
5779                 .owner =        THIS_MODULE,
5780                 .pf =           PF_INET,
5781                 .hooknum =      NF_INET_LOCAL_OUT,
5782                 .priority =     NF_IP_PRI_SELINUX_FIRST,
5783         }
5784 };
5785
5786 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
5787
5788 static struct nf_hook_ops selinux_ipv6_ops[] = {
5789         {
5790                 .hook =         selinux_ipv6_postroute,
5791                 .owner =        THIS_MODULE,
5792                 .pf =           PF_INET6,
5793                 .hooknum =      NF_INET_POST_ROUTING,
5794                 .priority =     NF_IP6_PRI_SELINUX_LAST,
5795         },
5796         {
5797                 .hook =         selinux_ipv6_forward,
5798                 .owner =        THIS_MODULE,
5799                 .pf =           PF_INET6,
5800                 .hooknum =      NF_INET_FORWARD,
5801                 .priority =     NF_IP6_PRI_SELINUX_FIRST,
5802         }
5803 };
5804
5805 #endif  /* IPV6 */
5806
5807 static int __init selinux_nf_ip_init(void)
5808 {
5809         int err = 0;
5810
5811         if (!selinux_enabled)
5812                 goto out;
5813
5814         printk(KERN_DEBUG "SELinux:  Registering netfilter hooks\n");
5815
5816         err = nf_register_hooks(selinux_ipv4_ops, ARRAY_SIZE(selinux_ipv4_ops));
5817         if (err)
5818                 panic("SELinux: nf_register_hooks for IPv4: error %d\n", err);
5819
5820 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
5821         err = nf_register_hooks(selinux_ipv6_ops, ARRAY_SIZE(selinux_ipv6_ops));
5822         if (err)
5823                 panic("SELinux: nf_register_hooks for IPv6: error %d\n", err);
5824 #endif  /* IPV6 */
5825
5826 out:
5827         return err;
5828 }
5829
5830 __initcall(selinux_nf_ip_init);
5831
5832 #ifdef CONFIG_SECURITY_SELINUX_DISABLE
5833 static void selinux_nf_ip_exit(void)
5834 {
5835         printk(KERN_DEBUG "SELinux:  Unregistering netfilter hooks\n");
5836
5837         nf_unregister_hooks(selinux_ipv4_ops, ARRAY_SIZE(selinux_ipv4_ops));
5838 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
5839         nf_unregister_hooks(selinux_ipv6_ops, ARRAY_SIZE(selinux_ipv6_ops));
5840 #endif  /* IPV6 */
5841 }
5842 #endif
5843
5844 #else /* CONFIG_NETFILTER */
5845
5846 #ifdef CONFIG_SECURITY_SELINUX_DISABLE
5847 #define selinux_nf_ip_exit()
5848 #endif
5849
5850 #endif /* CONFIG_NETFILTER */
5851
5852 #ifdef CONFIG_SECURITY_SELINUX_DISABLE
5853 static int selinux_disabled;
5854
5855 int selinux_disable(void)
5856 {
5857         if (ss_initialized) {
5858                 /* Not permitted after initial policy load. */
5859                 return -EINVAL;
5860         }
5861
5862         if (selinux_disabled) {
5863                 /* Only do this once. */
5864                 return -EINVAL;
5865         }
5866
5867         printk(KERN_INFO "SELinux:  Disabled at runtime.\n");
5868
5869         selinux_disabled = 1;
5870         selinux_enabled = 0;
5871
5872         reset_security_ops();
5873
5874         /* Try to destroy the avc node cache */
5875         avc_disable();
5876
5877         /* Unregister netfilter hooks. */
5878         selinux_nf_ip_exit();
5879
5880         /* Unregister selinuxfs. */
5881         exit_sel_fs();
5882
5883         return 0;
5884 }
5885 #endif